Bumped version to 0.6.2

SCTP optimizations

.clang-format

@@ -10,5 +10,7 @@ AccessModifierOffset: -4
 ColumnLimit: 100
 ---
 Language: JavaScript
-ColumnLimit: 80
+IndentWidth: 2
+UseTab: Never
+ColumnLimit: 100
 ...

.editorconfig

@@ -9,3 +9,13 @@ insert_final_newline = true
 indent_style = tab
 indent_size = 4
 
+[*.js]
+insert_final_newline = true
+indent_style = space
+indent_size = 2
+
+[*.py]
+insert_final_newline = false
+indent_style = space
+indent_size = 4
+

.github/dependabot.yml

@@ -0,0 +1,6 @@
+version: 2
+updates:
+  - package-ecosystem: "npm"
+    directory: "examples/web"
+    schedule:
+      interval: "weekly"

.github/workflows/build-gnutls.yml

@@ -0,0 +1,40 @@
+name: Build and test with GnuTLS
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+    branches:
+    - master
+jobs:
+  build-ubuntu:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: install packages
+      run: sudo apt update && sudo apt install libgnutls28-dev nettle-dev
+    - name: submodules
+      run: git submodule update --init --recursive
+    - name: cmake
+      run: cmake -B build -DUSE_JUICE=1 -DUSE_GNUTLS=1
+    - name: make
+      run: (cd build; make -j2)
+    - name: test
+      run: ./build/tests
+  build-macos:
+    runs-on: macos-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: install packages
+      run: brew install gnutls nettle
+    - name: submodules
+      run: git submodule update --init --recursive
+    - name: cmake
+      run: cmake -B build -DUSE_JUICE=1 -DUSE_GNUTLS=1
+      env:
+# hack to bypass EPERM issue on sendto()
+        CFLAGS: -DJUICE_ENABLE_ADDRS_LOCALHOST
+    - name: make
+      run: (cd build; make -j2)
+    - name: test
+      run: ./build/tests

.github/workflows/build-nice.yml

@@ -0,0 +1,24 @@
+name: Build and test with libnice
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+    branches:
+    - master
+jobs:
+  build-ubuntu:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: install packages
+      run: sudo apt update && sudo apt install libgnutls28-dev libnice-dev
+    - name: submodules
+      run: git submodule update --init --recursive
+    - name: cmake
+      run: cmake -B build -DUSE_JUICE=0 -DUSE_GNUTLS=1
+    - name: make
+      run: (cd build; make -j2)
+    - name: test
+      run: ./build/tests
+

.github/workflows/build-openssl.yml

@@ -0,0 +1,42 @@
+name: Build and test with OpenSSL
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+    branches:
+    - master
+jobs:
+  build-ubuntu:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: install packages
+      run: sudo apt update && sudo apt install libssl-dev
+    - name: submodules
+      run: git submodule update --init --recursive
+    - name: cmake
+      run: cmake -B build -DUSE_JUICE=1 -DUSE_GNUTLS=0
+    - name: make
+      run: (cd build; make -j2)
+    - name: test
+      run: ./build/tests
+  build-macos:
+    runs-on: macos-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: install packages
+      run: brew reinstall openssl@1.1
+    - name: submodules
+      run: git submodule update --init --recursive
+    - name: cmake
+      run: cmake -B build -DUSE_JUICE=1 -DUSE_GNUTLS=0
+      env:
+        OPENSSL_ROOT_DIR: /usr/local/opt/openssl
+        OPENSSL_LIBRARIES: /usr/local/opt/openssl/lib
+# hack to bypass EPERM issue on sendto()
+        CFLAGS: -DJUICE_ENABLE_ADDRS_LOCALHOST
+    - name: make
+      run: (cd build; make -j2)
+    - name: test
+      run: ./build/tests

.gitignore

@@ -1,7 +1,10 @@
+build/
+node_modules/
 *.d
 *.o
 *.a
 *.so
 compile_commands.json
 tests
+.DS_Store
 

.gitmodules

@@ -1,3 +1,12 @@
+[submodule "deps/plog"]
+	path = deps/plog
+	url = https://github.com/SergiusTheBest/plog
 [submodule "usrsctp"]
-	path = usrsctp
+	path = deps/usrsctp
 	url = https://github.com/sctplab/usrsctp.git
+[submodule "deps/libjuice"]
+	path = deps/libjuice
+	url = https://github.com/paullouisageneau/libjuice
+[submodule "deps/json"]
+	path = deps/json
+	url = https://github.com/nlohmann/json.git

CMakeLists.txt

@@ -0,0 +1,226 @@
+cmake_minimum_required(VERSION 3.7)
+project(libdatachannel
+	DESCRIPTION "WebRTC DataChannels Library"
+	VERSION 0.6.2
+	LANGUAGES CXX)
+
+option(USE_GNUTLS "Use GnuTLS instead of OpenSSL" OFF)
+option(USE_JUICE "Use libjuice instead of libnice" OFF)
+option(RTC_ENABLE_WEBSOCKET "Build WebSocket support" ON)
+
+if(USE_GNUTLS)
+	option(USE_NETTLE "Use Nettle instead of OpenSSL in libjuice" ON)
+else()
+	option(USE_NETTLE "Use Nettle instead of OpenSSL in libjuice" OFF)
+endif()
+
+set(CMAKE_POSITION_INDEPENDENT_CODE ON)
+set(CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake/Modules)
+
+if(WIN32)
+	add_definitions(-DWIN32_LEAN_AND_MEAN)
+	if (MSVC)
+		add_definitions(-DNOMINMAX)
+	endif()
+endif()
+
+set(LIBDATACHANNEL_SOURCES
+	${CMAKE_CURRENT_SOURCE_DIR}/src/candidate.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/certificate.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/channel.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/configuration.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/datachannel.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/description.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/dtlssrtptransport.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/dtlstransport.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/icetransport.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/init.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/log.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/peerconnection.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/rtc.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/sctptransport.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/tls.cpp
+)
+
+set(LIBDATACHANNEL_WEBSOCKET_SOURCES
+	${CMAKE_CURRENT_SOURCE_DIR}/src/base64.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/tcptransport.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/tlstransport.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/websocket.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/wstransport.cpp
+)
+
+set(LIBDATACHANNEL_HEADERS
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/candidate.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/channel.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/configuration.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/configuration.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/datachannel.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/description.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/include.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/init.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/log.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/message.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/peerconnection.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/queue.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/reliability.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/rtc.h
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/rtc.hpp
+	${CMAKE_CURRENT_SOURCE_DIR}/include/rtc/websocket.hpp
+)
+
+set(TESTS_SOURCES
+    ${CMAKE_CURRENT_SOURCE_DIR}/test/main.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/test/connectivity.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/test/capi.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/test/websocket.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/test/benchmark.cpp
+)
+
+set(CMAKE_THREAD_PREFER_PTHREAD TRUE)
+set(THREADS_PREFER_PTHREAD_FLAG TRUE)
+find_package(Threads REQUIRED)
+find_package(SRTP)
+
+set(CMAKE_POLICY_DEFAULT_CMP0048 NEW)
+add_subdirectory(deps/plog)
+
+add_subdirectory(deps/usrsctp EXCLUDE_FROM_ALL)
+if (MSYS OR MINGW)
+	target_compile_definitions(usrsctp PUBLIC -DSCTP_STDINT_INCLUDE=<stdint.h>)
+	target_compile_definitions(usrsctp-static PUBLIC -DSCTP_STDINT_INCLUDE=<stdint.h>)
+endif()
+if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
+    target_compile_options(usrsctp PRIVATE -Wno-error=format-truncation)
+	target_compile_options(usrsctp-static PRIVATE -Wno-error=format-truncation)
+endif()
+add_library(Usrsctp::Usrsctp ALIAS usrsctp)
+add_library(Usrsctp::UsrsctpStatic ALIAS usrsctp-static)
+
+if (RTC_ENABLE_WEBSOCKET)
+	add_library(datachannel SHARED
+		${LIBDATACHANNEL_SOURCES}
+		${LIBDATACHANNEL_WEBSOCKET_SOURCES})
+	add_library(datachannel-static STATIC EXCLUDE_FROM_ALL
+		${LIBDATACHANNEL_SOURCES}
+		${LIBDATACHANNEL_WEBSOCKET_SOURCES})
+	target_compile_definitions(datachannel PUBLIC RTC_ENABLE_WEBSOCKET=1)
+	target_compile_definitions(datachannel-static PUBLIC RTC_ENABLE_WEBSOCKET=1)
+else()
+	add_library(datachannel SHARED
+		${LIBDATACHANNEL_SOURCES})
+	add_library(datachannel-static STATIC EXCLUDE_FROM_ALL
+		${LIBDATACHANNEL_SOURCES})
+	target_compile_definitions(datachannel PUBLIC RTC_ENABLE_WEBSOCKET=0)
+	target_compile_definitions(datachannel-static PUBLIC RTC_ENABLE_WEBSOCKET=0)
+endif()
+
+set_target_properties(datachannel PROPERTIES
+	VERSION ${PROJECT_VERSION}
+	CXX_STANDARD 17)
+set_target_properties(datachannel-static PROPERTIES
+	VERSION ${PROJECT_VERSION}
+	CXX_STANDARD 17)
+
+target_include_directories(datachannel PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include)
+target_include_directories(datachannel PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/include/rtc)
+target_include_directories(datachannel PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
+target_link_libraries(datachannel PUBLIC Threads::Threads plog::plog)
+target_link_libraries(datachannel PRIVATE Usrsctp::UsrsctpStatic)
+
+target_include_directories(datachannel-static PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include)
+target_include_directories(datachannel-static PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/include/rtc)
+target_include_directories(datachannel-static PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
+target_link_libraries(datachannel-static PUBLIC Threads::Threads plog::plog)
+target_link_libraries(datachannel-static PRIVATE Usrsctp::UsrsctpStatic)
+
+if(WIN32)
+	target_link_libraries(datachannel PRIVATE wsock32 ws2_32) # winsock2
+	target_link_libraries(datachannel-static PRIVATE wsock32 ws2_32) # winsock2
+endif()
+
+if(SRTP_FOUND)
+	if(NOT TARGET SRTP::SRTP)
+		add_library(SRTP::SRTP UNKNOWN IMPORTED)
+		set_target_properties(SRTP::SRTP PROPERTIES
+			INTERFACE_INCLUDE_DIRECTORIES ${SRTP_INCLUDE_DIRS}
+			IMPORTED_LINK_INTERFACE_LANGUAGES C
+			IMPORTED_LOCATION ${SRTP_LIBRARIES})
+	endif()
+	target_compile_definitions(datachannel PUBLIC RTC_ENABLE_MEDIA=1)
+	target_compile_definitions(datachannel-static PUBLIC RTC_ENABLE_MEDIA=1)
+	target_link_libraries(datachannel PRIVATE SRTP::SRTP)
+	target_link_libraries(datachannel-static PRIVATE SRTP::SRTP)
+else()
+	target_compile_definitions(datachannel PUBLIC RTC_ENABLE_MEDIA=0)
+	target_compile_definitions(datachannel-static PUBLIC RTC_ENABLE_MEDIA=0)
+endif()
+
+if (USE_GNUTLS)
+	find_package(GnuTLS REQUIRED)
+	if(NOT TARGET GnuTLS::GnuTLS)
+		add_library(GnuTLS::GnuTLS UNKNOWN IMPORTED)
+		set_target_properties(GnuTLS::GnuTLS PROPERTIES
+			INTERFACE_INCLUDE_DIRECTORIES "${GNUTLS_INCLUDE_DIRS}"
+			INTERFACE_COMPILE_DEFINITIONS "${GNUTLS_DEFINITIONS}"
+			IMPORTED_LINK_INTERFACE_LANGUAGES C
+			IMPORTED_LOCATION "${GNUTLS_LIBRARIES}")
+	endif()
+	target_compile_definitions(datachannel PRIVATE USE_GNUTLS=1)
+	target_compile_definitions(datachannel-static PRIVATE USE_GNUTLS=1)
+	target_link_libraries(datachannel PRIVATE GnuTLS::GnuTLS)
+	target_link_libraries(datachannel-static PRIVATE GnuTLS::GnuTLS)
+else()
+	find_package(OpenSSL REQUIRED)
+	target_compile_definitions(datachannel PRIVATE USE_GNUTLS=0)
+	target_compile_definitions(datachannel-static PRIVATE USE_GNUTLS=0)
+	target_link_libraries(datachannel PRIVATE OpenSSL::SSL)
+	target_link_libraries(datachannel-static PRIVATE OpenSSL::SSL)
+endif()
+
+if (USE_JUICE)
+	add_subdirectory(deps/libjuice EXCLUDE_FROM_ALL)
+	target_compile_definitions(datachannel PRIVATE USE_JUICE=1)
+	target_compile_definitions(datachannel-static PRIVATE USE_JUICE=1)
+	target_link_libraries(datachannel PRIVATE LibJuice::LibJuiceStatic)
+	target_link_libraries(datachannel-static PRIVATE LibJuice::LibJuiceStatic)
+else()
+	find_package(LibNice REQUIRED)
+	target_compile_definitions(datachannel PRIVATE USE_JUICE=0)
+	target_compile_definitions(datachannel-static PRIVATE USE_JUICE=0)
+	target_link_libraries(datachannel PRIVATE LibNice::LibNice)
+	target_link_libraries(datachannel-static PRIVATE LibNice::LibNice)
+endif()
+
+add_library(LibDataChannel::LibDataChannel ALIAS datachannel)
+add_library(LibDataChannel::LibDataChannelStatic ALIAS datachannel-static)
+
+install(TARGETS datachannel LIBRARY DESTINATION lib)
+install(FILES ${LIBDATACHANNEL_HEADERS} DESTINATION include/rtc)
+
+# Tests
+add_executable(datachannel-tests ${TESTS_SOURCES})
+set_target_properties(datachannel-tests PROPERTIES
+	VERSION ${PROJECT_VERSION}
+	CXX_STANDARD 17)
+set_target_properties(datachannel-tests PROPERTIES OUTPUT_NAME tests)
+target_include_directories(datachannel-tests PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
+target_link_libraries(datachannel-tests datachannel nlohmann_json::nlohmann_json)
+
+# Benchmark
+add_executable(datachannel-benchmark test/benchmark.cpp)
+set_target_properties(datachannel-benchmark PROPERTIES
+	VERSION ${PROJECT_VERSION}
+	CXX_STANDARD 17)
+set_target_properties(datachannel-benchmark PROPERTIES OUTPUT_NAME benchmark)
+target_compile_definitions(datachannel-benchmark PRIVATE BENCHMARK_MAIN=1)
+target_include_directories(datachannel-benchmark PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
+target_link_libraries(datachannel-benchmark datachannel)
+
+# Examples
+set(JSON_BuildTests OFF CACHE INTERNAL "")
+add_subdirectory(deps/json)
+add_subdirectory(examples/client)
+add_subdirectory(examples/copy-paste)
+add_subdirectory(examples/copy-paste-capi)
+

Jamfile

@@ -0,0 +1,88 @@
+import feature : feature ;
+
+project libdatachannel ;
+path-constant CWD : . ;
+
+lib libdatachannel
+	: # sources
+	[ glob ./src/*.cpp ]
+	: # requirements
+	<cxxstd>17
+	<include>./include/rtc
+	<define>USE_JUICE=1
+	<define>RTC_ENABLE_MEDIA=0
+	<define>RTC_ENABLE_WEBSOCKET=0
+	<library>/libdatachannel//usrsctp
+	<library>/libdatachannel//juice
+	<library>/libdatachannel//plog
+	: # default build
+	<link>static
+	: # usage requirements
+	<include>./include
+	<library>/libdatachannel//plog
+	<cxxflags>-pthread
+	<toolset>gcc:<cxxflags>"-Wno-pedantic -Wno-unused-parameter -Wno-unused-variable"
+	<toolset>clang:<cxxflags>"-Wno-pedantic -Wno-unused-parameter -Wno-unused-variable"
+	;
+
+feature gnutls : off on : composite propagated ;
+feature.compose <gnutls>off
+    : <define>USE_GNUTLS=0 ;
+feature.compose <gnutls>on
+    : <define>USE_GNUTLS=1 ;
+
+alias plog
+    : # no sources
+    : # no build requirements
+    : # no default build
+    : # usage requirements
+    <include>./deps/plog/include
+    ;
+
+alias usrsctp
+    : # no sources
+    : # no build requirements
+    : # no default build
+    : # usage requirements
+    <include>./deps/usrsctp/usrsctplib
+	<library>libusrsctp.a
+    ;
+
+alias juice
+    : # no sources
+    : # no build requirements
+    : # no default build
+    : # usage requirements
+    <include>./deps/libjuice/include
+	<library>libjuice.a
+    ;
+
+make libusrsctp.a : : @make_libusrsctp ;
+actions make_libusrsctp
+{
+	(cd $(CWD)/deps/usrsctp && \
+		./bootstrap && \
+		./configure --enable-static --disable-debug CFLAGS="-fPIC -Wno-address-of-packed-member" && \
+		make)
+    cp $(CWD)/deps/usrsctp/usrsctplib/.libs/libusrsctp.a $(<)
+}
+
+make libjuice.a : : @make_libjuice ;
+
+rule make_libjuice ( targets * : sources * : properties * )
+{
+	if <crypto>gnutls in $(properties)
+	{
+		MAKEOPTS on $(targets) = "USE_NETTLE=1" ;
+	}
+	else
+	{
+		MAKEOPTS on $(targets) = "USE_NETTLE=0" ;
+	}
+}
+actions make_libjuice
+{
+	(cd $(CWD)/deps/libjuice && make $(MAKEOPTS))
+    cp $(CWD)/deps/libjuice/libjuice.a $(<)
+}
+

Makefile

@@ -4,36 +4,83 @@ NAME=libdatachannel
 CXX=$(CROSS)g++
 AR=$(CROSS)ar
 RM=rm -f
-CPPFLAGS=-O2 -pthread -fPIC -Wall -Wno-address-of-packed-member
 CXXFLAGS=-std=c++17
+CPPFLAGS=-O2 -pthread -fPIC -Wall
 LDFLAGS=-pthread
-LDLIBS= -lgnutls $(shell pkg-config --libs glib-2.0 gobject-2.0 nice)
+LIBS=
-INCLUDES=-Iinclude/rtc -I$(USRSCTP_DIR)/usrsctplib $(shell pkg-config --cflags glib-2.0 gobject-2.0 nice)
+LOCALLIBS=libusrsctp.a
+USRSCTP_DIR=deps/usrsctp
+JUICE_DIR=deps/libjuice
+PLOG_DIR=deps/plog
 
-USRSCTP_DIR:=usrsctp
+INCLUDES=-Iinclude/rtc -I$(PLOG_DIR)/include -I$(USRSCTP_DIR)/usrsctplib
-USRSCTP_DEFINES:=-DINET -DINET6
+LDLIBS=
+
+USE_GNUTLS ?= 0
+ifneq ($(USE_GNUTLS), 0)
+        CPPFLAGS+=-DUSE_GNUTLS=1
+        LIBS+=gnutls
+else
+        CPPFLAGS+=-DUSE_GNUTLS=0
+        LIBS+=openssl
+endif
+
+USE_JUICE ?= 0
+ifneq ($(USE_JUICE), 0)
+        CPPFLAGS+=-DUSE_JUICE=1
+        INCLUDES+=-I$(JUICE_DIR)/include
+        LOCALLIBS+=libjuice.a
+ifneq ($(USE_GNUTLS), 0)
+        LIBS+=nettle
+endif
+else
+        CPPFLAGS+=-DUSE_JUICE=0
+        LIBS+=glib-2.0 gobject-2.0 nice
+endif
+
+RTC_ENABLE_MEDIA ?= 0
+ifneq ($(RTC_ENABLE_MEDIA), 0)
+        CPPFLAGS+=-DRTC_ENABLE_MEDIA=1
+        LIBS+=srtp
+else
+        CPPFLAGS+=-DRTC_ENABLE_MEDIA=0
+endif
+
+RTC_ENABLE_WEBSOCKET ?= 1
+ifneq ($(RTC_ENABLE_WEBSOCKET), 0)
+        CPPFLAGS+=-DRTC_ENABLE_WEBSOCKET=1
+else
+        CPPFLAGS+=-DRTC_ENABLE_WEBSOCKET=0
+endif
+
+
+INCLUDES+=$(shell pkg-config --cflags $(LIBS))
+LDLIBS+=$(LOCALLIBS) $(shell pkg-config --libs $(LIBS))
 
 SRCS=$(shell printf "%s " src/*.cpp)
 OBJS=$(subst .cpp,.o,$(SRCS))
 
+TEST_SRCS=$(shell printf "%s " test/*.cpp)
+TEST_OBJS=$(subst .cpp,.o,$(TEST_SRCS))
+
 all: $(NAME).a $(NAME).so tests
 
 src/%.o: src/%.cpp
-	$(CXX) $(CXXFLAGS) $(CPPFLAGS) $(INCLUDES) $(USRSCTP_DEFINES) -MMD -MP -o $@ -c $<
+	$(CXX) $(CXXFLAGS) $(CPPFLAGS) $(INCLUDES) -MMD -MP -o $@ -c $<
 
 test/%.o: test/%.cpp
-	$(CXX) $(CXXFLAGS) $(CPPFLAGS) -Iinclude -MMD -MP -o $@ -c $<
+	$(CXX) $(CXXFLAGS) $(CPPFLAGS) $(INCLUDES) -Iinclude -Isrc -MMD -MP -o $@ -c $<
 
 -include $(subst .cpp,.d,$(SRCS))
 
 $(NAME).a: $(OBJS)
 	$(AR) crf $@ $(OBJS)
 
-$(NAME).so: libusrsctp.a $(OBJS)
+$(NAME).so: $(LOCALLIBS) $(OBJS)
-	$(CXX) $(LDFLAGS) -shared -o $@ $(OBJS) $(LDLIBS) libusrsctp.a
+	$(CXX) $(LDFLAGS) -shared -o $@ $(OBJS) $(LDLIBS)
 
-tests: $(NAME).a test/main.o
+tests: $(NAME).a $(TEST_OBJS)
-	$(CXX) $(LDFLAGS) -o $@ test/main.o $(LDLIBS) $(NAME).a libusrsctp.a
+	$(CXX) $(LDFLAGS) -o $@ $(TEST_OBJS) $(NAME).a $(LDLIBS)
 
 clean:
 	-$(RM) include/rtc/*.d *.d
@@ -44,16 +91,26 @@ dist-clean: clean
 	-$(RM) $(NAME).a
 	-$(RM) $(NAME).so
 	-$(RM) libusrsctp.a
+	-$(RM) libjuice.a
 	-$(RM) tests
 	-$(RM) include/*~
 	-$(RM) src/*~
 	-$(RM) test/*~
 	-cd $(USRSCTP_DIR) && make clean
+	-cd $(JUICE_DIR) && make clean
 
 libusrsctp.a:
 	cd $(USRSCTP_DIR) && \
 		./bootstrap && \
-		./configure --enable-static --disable-debug CFLAGS="$(CPPFLAGS)" && \
+		./configure --enable-static --disable-debug CFLAGS="$(CPPFLAGS) -Wno-error=format-truncation" && \
 		make
 	cp $(USRSCTP_DIR)/usrsctplib/.libs/libusrsctp.a .
 
+libjuice.a:
+ifneq ($(USE_GNUTLS), 0)
+	cd $(JUICE_DIR) && make USE_NETTLE=1
+else
+	cd $(JUICE_DIR) && make USE_NETTLE=0
+endif
+	cp $(JUICE_DIR)/libjuice.a .
+

README.md

@@ -1,6 +1,9 @@
-# libdatachannel - C/C++ WebRTC DataChannels
+# libdatachannel - C/C++ WebRTC Data Channels
 
-libdatachannel is a standalone implementation of WebRTC DataChannels in C++17 with C bindings. It enables direct connectivity between native applications and web browsers without the pain of importing the entire WebRTC stack. Its API is modelled as a simplified version of the JavaScript WebRTC API, in order to ease the design of cross-environment applications.
+libdatachannel is a standalone implementation of WebRTC Data Channels and WebSockets in C++17 with C bindings for POSIX platforms (including Linux and Apple macOS) and Microsoft Windows. It enables direct connectivity between native applications and web browsers without the pain of importing the entire WebRTC stack. The interface consists of simplified versions of the JavaScript WebRTC and WebSocket APIs present in browsers, in order to ease the design of cross-environment applications.
+It can be compiled with multiple backends:
+- The security layer can be provided through [GnuTLS](https://www.gnutls.org/) or [OpenSSL](https://www.openssl.org/).
+- The connectivity for WebRTC can be provided through my ad-hoc ICE library [libjuice](https://github.com/paullouisageneau/libjuice) as submodule or through [libnice](https://github.com/libnice/libnice).
 
 This projet is originally inspired by [librtcdcpp](https://github.com/chadnickbok/librtcdcpp), however it is a complete rewrite from scratch, because the messy architecture of librtcdcpp made solving its implementation issues difficult.
 
@@ -8,26 +11,72 @@ Licensed under LGPLv2, see [LICENSE](https://github.com/paullouisageneau/libdata
 
 ## Compatibility
 
-This implementation has been tested to be compatible with Firefox and Chromium. It supports IPv6 and Multicast DNS candidates resolution provided the operating system also supports it.
+The library aims at implementing the following communication protocols:
+
+### WebRTC Data Channel
+
+The WebRTC stack has been tested to be compatible with Firefox and Chromium.
+
+Protocol stack:
+- SCTP-based Data Channels ([draft-ietf-rtcweb-data-channel-13](https://tools.ietf.org/html/draft-ietf-rtcweb-data-channel-13))
+- DTLS/UDP ([RFC7350](https://tools.ietf.org/html/rfc7350) and [RFC8261](https://tools.ietf.org/html/rfc8261))
+- ICE ([RFC8445](https://tools.ietf.org/html/rfc8445)) with STUN ([RFC5389](https://tools.ietf.org/html/rfc5389))
+
+Features:
+- Full IPv6 support
+- Trickle ICE ([draft-ietf-ice-trickle-21](https://tools.ietf.org/html/draft-ietf-ice-trickle-21))
+- JSEP compatible ([draft-ietf-rtcweb-jsep-26](https://tools.ietf.org/html/draft-ietf-rtcweb-jsep-26))
+- Multicast DNS candidates ([draft-ietf-rtcweb-mdns-ice-candidates-04](https://tools.ietf.org/html/draft-ietf-rtcweb-mdns-ice-candidates-04))
+- TURN relaying ([RFC5766](https://tools.ietf.org/html/rfc5766)) with [libnice](https://github.com/libnice/libnice) as ICE backend
+- SRTP media transport ([RFC3711](https://tools.ietf.org/html/rfc3711)) with [libSRTP](https://github.com/cisco/libsrtp)
+
+### WebSocket
+
+WebSocket is the protocol of choice for WebRTC signaling. The support is optional and can be disabled at compile time.
+
+Protocol stack:
+- WebSocket protocol ([RFC6455](https://tools.ietf.org/html/rfc6455)), client-side only
+- HTTP over TLS ([RFC2818](https://tools.ietf.org/html/rfc2818))
+
+Features:
+- IPv6 and IPv4/IPv6 dual-stack support
+- Keepalive with ping/pong
 
 ## Dependencies
 
-- libnice: https://github.com/libnice/libnice
+- GnuTLS: https://www.gnutls.org/ or OpenSSL: https://www.openssl.org/
-- GnuTLS: https://www.gnutls.org/
+
+Optional:
+- libnice: https://nice.freedesktop.org/ (substituable with libjuice)
+- libSRTP: https://github.com/cisco/libsrtp
 
 Submodules:
+- libjuice: https://github.com/paullouisageneau/libjuice
 - usrsctp: https://github.com/sctplab/usrsctp
 
 ## Building
+### Building with CMake (preferred)
 
 ```bash
 $ git submodule update --init --recursive
+$ mkdir build
+$ cd build
+$ cmake -DUSE_JUICE=1 -DUSE_GNUTLS=1 ..
 $ make
 ```
 
-## Example
+### Building directly with Make
 
-In the following example, note the callbacks are called in another thread.
+```bash
+$ git submodule update --init --recursive
+$ make USE_JUICE=1 USE_GNUTLS=1
+```
+
+## Examples
+
+See [examples](https://github.com/paullouisageneau/libdatachannel/blob/master/examples/) for a complete usage example with signaling server (under GPLv2).
+
+Additionnaly, you might want to have a look at the [C API](https://github.com/paullouisageneau/libdatachannel/blob/dev/include/rtc/rtc.h).
 
 ### Signal a PeerConnection
 
@@ -47,6 +96,7 @@ pc->onLocalDescription([](const rtc::Description &sdp) {
 });
 
 pc->onLocalCandidate([](const rtc::Candidate &candidate) {
+    // Send the candidate to the remote peer
     MY_SEND_CANDIDATE_TO_REMOTE(candidate.candidate(), candidate.mid());
 });
 
@@ -62,11 +112,11 @@ MY_ON_RECV_CANDIDATE_FROM_REMOTE([pc](string candidate, string mid) {
 ### Observe the PeerConnection state
 
 ```cpp
-pc->onStateChanged([](PeerConnection::State state) {
+pc->onStateChange([](PeerConnection::State state) {
     cout << "State: " << state << endl;
 });
 
-pc->onGatheringStateChanged([](PeerConnection::GatheringState state) {
+pc->onGatheringStateChange([](PeerConnection::GatheringState state) {
     cout << "Gathering state: " << state << endl;
 });
 
@@ -76,9 +126,11 @@ pc->onGatheringStateChanged([](PeerConnection::GatheringState state) {
 
 ```cpp
 auto dc = pc->createDataChannel("test");
+
 dc->onOpen([]() {
     cout << "Open" << endl;
 });
+
 dc->onMessage([](const variant<binary, string> &message) {
     if (holds_alternative<string>(message)) {
         cout << "Received: " << get<string>(message) << endl;
@@ -97,5 +149,22 @@ pc->onDataChannel([&dc](shared_ptr<rtc::DataChannel> incoming) {
 
 ```
 
-See [test/main.cpp](https://github.com/paullouisageneau/libdatachannel/blob/master/test/main.cpp) for a complete local connection example.
+### Open a WebSocket
+
+```cpp
+auto ws = make_shared<rtc::WebSocket>();
+
+ws->onOpen([]() {
+	cout << "WebSocket open" << endl;
+});
+
+ws->onMessage([](const variant<binary, string> &message) {
+    if (holds_alternative<string>(message)) {
+        cout << "WebSocket received: " << get<string>(message) << endl;
+    }
+});
+
+ws->open("wss://my.websocket/service");
+
+```
 

cmake/Modules/FindGLIB.cmake

@@ -0,0 +1,123 @@
+# - Try to find Glib and its components (gio, gobject etc)
+# Once done, this will define
+#
+#  GLIB_FOUND - system has Glib
+#  GLIB_INCLUDE_DIRS - the Glib include directories
+#  GLIB_LIBRARIES - link these to use Glib
+#
+# Optionally, the COMPONENTS keyword can be passed to find_package()
+# and Glib components can be looked for.  Currently, the following
+# components can be used, and they define the following variables if
+# found:
+#
+#  gio:             GLIB_GIO_LIBRARIES
+#  gobject:         GLIB_GOBJECT_LIBRARIES
+#  gmodule:         GLIB_GMODULE_LIBRARIES
+#  gthread:         GLIB_GTHREAD_LIBRARIES
+#
+# Note that the respective _INCLUDE_DIR variables are not set, since
+# all headers are in the same directory as GLIB_INCLUDE_DIRS.
+#
+# Copyright (C) 2012 Raphael Kubo da Costa <rakuco@webkit.org>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1.  Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+# 2.  Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER AND ITS CONTRIBUTORS ``AS
+# IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR ITS
+# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+# EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+# OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+# OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+# ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+find_package(PkgConfig)
+pkg_check_modules(PC_GLIB QUIET glib-2.0)
+
+find_library(GLIB_LIBRARIES
+    NAMES glib-2.0
+    HINTS ${PC_GLIB_LIBDIR}
+          ${PC_GLIB_LIBRARY_DIRS}
+)
+
+# Files in glib's main include path may include glibconfig.h, which,
+# for some odd reason, is normally in $LIBDIR/glib-2.0/include.
+get_filename_component(_GLIB_LIBRARY_DIR ${GLIB_LIBRARIES} PATH)
+find_path(GLIBCONFIG_INCLUDE_DIR
+    NAMES glibconfig.h
+    HINTS ${PC_LIBDIR} ${PC_LIBRARY_DIRS} ${_GLIB_LIBRARY_DIR}
+          ${PC_GLIB_INCLUDEDIR} ${PC_GLIB_INCLUDE_DIRS}
+    PATH_SUFFIXES glib-2.0/include
+)
+
+find_path(GLIB_INCLUDE_DIR
+    NAMES glib.h
+    HINTS ${PC_GLIB_INCLUDEDIR}
+          ${PC_GLIB_INCLUDE_DIRS}
+    PATH_SUFFIXES glib-2.0
+)
+
+set(GLIB_INCLUDE_DIRS ${GLIB_INCLUDE_DIR} ${GLIBCONFIG_INCLUDE_DIR})
+
+# Version detection
+if (EXISTS "${GLIBCONFIG_INCLUDE_DIR}/glibconfig.h")
+    file(READ "${GLIBCONFIG_INCLUDE_DIR}/glibconfig.h" GLIBCONFIG_H_CONTENTS)
+    string(REGEX MATCH "#define GLIB_MAJOR_VERSION ([0-9]+)" _dummy "${GLIBCONFIG_H_CONTENTS}")
+    set(GLIB_VERSION_MAJOR "${CMAKE_MATCH_1}")
+    string(REGEX MATCH "#define GLIB_MINOR_VERSION ([0-9]+)" _dummy "${GLIBCONFIG_H_CONTENTS}")
+    set(GLIB_VERSION_MINOR "${CMAKE_MATCH_1}")
+    string(REGEX MATCH "#define GLIB_MICRO_VERSION ([0-9]+)" _dummy "${GLIBCONFIG_H_CONTENTS}")
+    set(GLIB_VERSION_MICRO "${CMAKE_MATCH_1}")
+    set(GLIB_VERSION "${GLIB_VERSION_MAJOR}.${GLIB_VERSION_MINOR}.${GLIB_VERSION_MICRO}")
+endif ()
+
+# Additional Glib components.  We only look for libraries, as not all of them
+# have corresponding headers and all headers are installed alongside the main
+# glib ones.
+foreach (_component ${GLIB_FIND_COMPONENTS})
+    if (${_component} STREQUAL "gio")
+        find_library(GLIB_GIO_LIBRARIES NAMES gio-2.0 HINTS ${_GLIB_LIBRARY_DIR})
+        set(ADDITIONAL_REQUIRED_VARS ${ADDITIONAL_REQUIRED_VARS} GLIB_GIO_LIBRARIES)
+    elseif (${_component} STREQUAL "gobject")
+        find_library(GLIB_GOBJECT_LIBRARIES NAMES gobject-2.0 HINTS ${_GLIB_LIBRARY_DIR})
+        set(ADDITIONAL_REQUIRED_VARS ${ADDITIONAL_REQUIRED_VARS} GLIB_GOBJECT_LIBRARIES)
+    elseif (${_component} STREQUAL "gmodule")
+        find_library(GLIB_GMODULE_LIBRARIES NAMES gmodule-2.0 HINTS ${_GLIB_LIBRARY_DIR})
+        set(ADDITIONAL_REQUIRED_VARS ${ADDITIONAL_REQUIRED_VARS} GLIB_GMODULE_LIBRARIES)
+    elseif (${_component} STREQUAL "gthread")
+        find_library(GLIB_GTHREAD_LIBRARIES NAMES gthread-2.0 HINTS ${_GLIB_LIBRARY_DIR})
+        set(ADDITIONAL_REQUIRED_VARS ${ADDITIONAL_REQUIRED_VARS} GLIB_GTHREAD_LIBRARIES)
+    elseif (${_component} STREQUAL "gio-unix")
+        # gio-unix is compiled as part of the gio library, but the include paths
+        # are separate from the shared glib ones. Since this is currently only used
+        # by WebKitGTK we don't go to extraordinary measures beyond pkg-config.
+        pkg_check_modules(GIO_UNIX QUIET gio-unix-2.0)
+    endif ()
+endforeach ()
+
+include(FindPackageHandleStandardArgs)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(GLIB REQUIRED_VARS GLIB_INCLUDE_DIRS GLIB_LIBRARIES ${ADDITIONAL_REQUIRED_VARS}
+                                       VERSION_VAR   GLIB_VERSION)
+
+mark_as_advanced(
+    GLIBCONFIG_INCLUDE_DIR
+    GLIB_GIO_LIBRARIES
+    GLIB_GIO_UNIX_LIBRARIES
+    GLIB_GMODULE_LIBRARIES
+    GLIB_GOBJECT_LIBRARIES
+    GLIB_GTHREAD_LIBRARIES
+    GLIB_INCLUDE_DIR
+    GLIB_INCLUDE_DIRS
+    GLIB_LIBRARIES
+)
+

cmake/Modules/FindLibNice.cmake

@@ -0,0 +1,35 @@
+if (NOT TARGET LibNice::LibNice)
+    find_package(PkgConfig)
+    pkg_check_modules(PC_LIBNICE nice)
+    set(LIBNICE_DEFINITIONS ${PC_LIBNICE_CFLAGS_OTHER})
+
+    find_path(LIBNICE_INCLUDE_DIR nice/agent.h
+            HINTS ${PC_LIBNICE_INCLUDEDIR} ${PC_LIBNICE_INCLUDE_DIRS}
+            PATH_SUFFICES libnice)
+    find_library(LIBNICE_LIBRARY NAMES nice libnice
+            HINTS ${PC_LIBNICE_LIBDIR} ${PC_LIBNICE_LIBRARY_DIRS})
+
+    include(FindPackageHandleStandardArgs)
+    find_package_handle_standard_args(LibNice DEFAULT_MSG
+            LIBNICE_LIBRARY LIBNICE_INCLUDE_DIR)
+    mark_as_advanced(LIBNICE_INCLUDE_DIR LIBNICE_LIBRARY)
+
+    set(LIBNICE_LIBRARIES ${LIBNICE_LIBRARY})
+    set(LIBNICE_INCLUDE_DIRS ${LIBNICE_INCLUDE_DIR})
+
+    find_package(GLIB REQUIRED COMPONENTS gio gobject gmodule gthread)
+
+    list(APPEND LIBNICE_INCLUDE_DIRS ${GLIB_INCLUDE_DIRS})
+    list(APPEND LIBNICE_LIBRARIES ${GLIB_GOBJECT_LIBRARIES} ${GLIB_LIBRARIES})
+
+    if (LIBNICE_FOUND)
+        add_library(LibNice::LibNice UNKNOWN IMPORTED)
+        set_target_properties(LibNice::LibNice PROPERTIES
+                IMPORTED_LOCATION "${LIBNICE_LIBRARY}"
+                INTERFACE_COMPILE_DEFINITIONS "_REENTRANT"
+                INTERFACE_INCLUDE_DIRECTORIES "${LIBNICE_INCLUDE_DIRS}"
+                INTERFACE_LINK_LIBRARIES "${LIBNICE_LIBRARIES}"
+                IMPORTED_LINK_INTERFACE_LANGUAGES "C")
+    endif ()
+endif ()
+

cmake/Modules/FindSRTP.cmake

@@ -0,0 +1,73 @@
+############################################################################
+# FindSRTP.txt
+# Copyright (C) 2014  Belledonne Communications, Grenoble France
+#
+############################################################################
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+############################################################################
+#
+# - Find the SRTP include file and library
+#
+#  SRTP_FOUND - system has SRTP
+#  SRTP_INCLUDE_DIRS - the SRTP include directory
+#  SRTP_LIBRARIES - The libraries needed to use SRTP
+
+set(_SRTP_ROOT_PATHS
+	${CMAKE_INSTALL_PREFIX}
+)
+
+find_path(SRTP2_INCLUDE_DIRS
+	NAMES srtp2/srtp.h
+	HINTS _SRTP_ROOT_PATHS
+	PATH_SUFFIXES include
+)
+
+if(SRTP2_INCLUDE_DIRS)
+	set(HAVE_SRTP_SRTP_H 1)
+	set(SRTP_INCLUDE_DIRS ${SRTP2_INCLUDE_DIRS})
+	set(SRTP_VERSION 2)
+	find_library(SRTP_LIBRARIES
+		NAMES srtp2
+		HINTS ${_SRTP_ROOT_PATHS}
+		PATH_SUFFIXES bin lib
+	)
+else()
+	find_path(SRTP_INCLUDE_DIRS
+		NAMES srtp/srtp.h
+		HINTS _SRTP_ROOT_PATHS
+		PATH_SUFFIXES include
+	)
+	if(SRTP_INCLUDE_DIRS)
+		set(HAVE_SRTP_SRTP_H 1)
+		set(SRTP_VERSION 1)
+	endif()
+	find_library(SRTP_LIBRARIES
+	NAMES srtp
+	HINTS ${_SRTP_ROOT_PATHS}
+	PATH_SUFFIXES bin lib
+)
+endif()
+
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(SRTP
+	DEFAULT_MSG
+	SRTP_INCLUDE_DIRS SRTP_LIBRARIES HAVE_SRTP_SRTP_H SRTP_VERSION
+)
+
+mark_as_advanced(SRTP_INCLUDE_DIRS SRTP_LIBRARIES HAVE_SRTP_SRTP_H SRTP_VERSION)
+

examples/README.md

@@ -0,0 +1,12 @@
+# Examples for libdatachannel
+
+This directory contains different WebRTC clients and WebSocket + JSON signaling servers.
+
+- [client](client) uses libdatachannel to implement WebRTC Data Channels with WebSocket signaling
+- [web](web) contains an equivalent implementation for web browsers and a node.js signaling server
+- [signaling-server-python](signaling-server-python) contains a similar signaling server in Python
+
+Additionally, it contains two debugging tools for libdatachannel with copy-pasting as signaling:
+- [copy-paste](copy-paste) using the C++ API
+- [copy-paste-capi](copy-paste-capi) using the C API
+

examples/client/CMakeLists.txt

@@ -0,0 +1,11 @@
+cmake_minimum_required(VERSION 3.7)
+if(POLICY CMP0079)
+	cmake_policy(SET CMP0079 NEW)
+endif()
+
+add_executable(datachannel-client main.cpp)
+set_target_properties(datachannel-client PROPERTIES
+	CXX_STANDARD 17
+	OUTPUT_NAME client)
+target_link_libraries(datachannel-client datachannel nlohmann_json)
+

examples/client/LICENSE

@@ -0,0 +1,339 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have.  You must make sure that they, too, receive or can get the
+source code.  And you must show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term "modification".)  Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+  1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+  2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+    a) You must cause the modified files to carry prominent notices
+    stating that you changed the files and the date of any change.
+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
+    interactive use in the most ordinary way, to print or display an
+    announcement including an appropriate copyright notice and a
+    notice that there is no warranty (or else, saying that you provide
+    a warranty) and that users may redistribute the program under
+    these conditions, and telling the user how to view a copy of this
+    License.  (Exception: if the Program itself is interactive but
+    does not normally print such an announcement, your work based on
+    the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+  3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+    a) Accompany it with the complete corresponding machine-readable
+    source code, which must be distributed under the terms of Sections
+    1 and 2 above on a medium customarily used for software interchange; or,
+
+    b) Accompany it with a written offer, valid for at least three
+    years, to give any third party, for a charge no more than your
+    cost of physically performing source distribution, a complete
+    machine-readable copy of the corresponding source code, to be
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+
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+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
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+    <one line to give the program's name and a brief idea of what it does.>
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+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
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+
+    Gnomovision version 69, Copyright (C) year name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
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+parts of the General Public License.  Of course, the commands you use may
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+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
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+
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+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.

examples/client/main.cpp

@@ -0,0 +1,218 @@
+/*
+ * libdatachannel client example
+ * Copyright (c) 2019-2020 Paul-Louis Ageneau
+ * Copyright (c) 2019 Murat Dogan
+ * Copyright (c) 2020 Will Munn
+ * Copyright (c) 2020 Nico Chatzi
+ * Copyright (c) 2020 Lara Mackey
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "rtc/rtc.hpp"
+
+#include <nlohmann/json.hpp>
+
+#include <algorithm>
+#include <iostream>
+#include <memory>
+#include <random>
+#include <thread>
+#include <unordered_map>
+
+using namespace rtc;
+using namespace std;
+using namespace std::chrono_literals;
+
+using json = nlohmann::json;
+
+template <class T> weak_ptr<T> make_weak_ptr(shared_ptr<T> ptr) { return ptr; }
+
+unordered_map<string, shared_ptr<PeerConnection>> peerConnectionMap;
+unordered_map<string, shared_ptr<DataChannel>> dataChannelMap;
+
+string localId;
+
+shared_ptr<PeerConnection> createPeerConnection(const Configuration &config,
+                                                weak_ptr<WebSocket> wws, string id);
+string randomId(size_t length);
+
+int main(int argc, char **argv) {
+	rtc::InitLogger(LogLevel::Warning);
+
+	Configuration config;
+	config.iceServers.emplace_back("stun:stun.l.google.com:19302"); // change to your STUN server
+
+	localId = randomId(4);
+	cout << "The local ID is: " << localId << endl;
+
+	auto ws = make_shared<WebSocket>();
+
+	ws->onOpen([]() { cout << "WebSocket connected, signaling ready" << endl; });
+
+	ws->onClosed([]() { cout << "WebSocket closed" << endl; });
+
+	ws->onError([](const string &error) { cout << "WebSocket failed: " << error << endl; });
+
+	ws->onMessage([&](const variant<binary, string> &data) {
+		if (!holds_alternative<string>(data))
+			return;
+
+		json message = json::parse(get<string>(data));
+
+		auto it = message.find("id");
+		if (it == message.end())
+			return;
+		string id = it->get<string>();
+
+		it = message.find("type");
+		if (it == message.end())
+			return;
+		string type = it->get<string>();
+
+		shared_ptr<PeerConnection> pc;
+		if (auto jt = peerConnectionMap.find(id); jt != peerConnectionMap.end()) {
+			pc = jt->second;
+		} else if (type == "offer") {
+			cout << "Answering to " + id << endl;
+			pc = createPeerConnection(config, ws, id);
+		} else {
+			return;
+		}
+
+		if (type == "offer" || type == "answer") {
+			auto sdp = message["description"].get<string>();
+			pc->setRemoteDescription(Description(sdp, type));
+		} else if (type == "candidate") {
+			auto sdp = message["candidate"].get<string>();
+			auto mid = message["mid"].get<string>();
+			pc->addRemoteCandidate(Candidate(sdp, mid));
+		}
+	});
+
+	const string url = "ws://localhost:8000/" + localId;
+	ws->open(url);
+
+	cout << "Waiting for signaling to be connected..." << endl;
+	while (!ws->isOpen()) {
+		if (ws->isClosed())
+			return 1;
+		this_thread::sleep_for(100ms);
+	}
+
+	while (true) {
+		string id;
+		cout << "Enter a remote ID to send an offer:" << endl;
+		cin >> id;
+		cin.ignore();
+		if (id.empty())
+			break;
+		if (id == localId)
+			continue;
+
+		cout << "Offering to " + id << endl;
+		auto pc = createPeerConnection(config, ws, id);
+
+		// We are the offerer, so create a data channel to initiate the process
+		const string label = "test";
+		cout << "Creating DataChannel with label \"" << label << "\"" << endl;
+		auto dc = pc->createDataChannel(label);
+
+		dc->onOpen([id, wdc = make_weak_ptr(dc)]() {
+			cout << "DataChannel from " << id << " open" << endl;
+			if (auto dc = wdc.lock())
+				dc->send("Hello from " + localId);
+		});
+
+		dc->onClosed([id]() { cout << "DataChannel from " << id << " closed" << endl; });
+
+		dc->onMessage([id](const variant<binary, string> &message) {
+			if (!holds_alternative<string>(message))
+				return;
+
+			cout << "Message from " << id << " received: " << get<string>(message) << endl;
+		});
+
+		dataChannelMap.emplace(id, dc);
+
+		this_thread::sleep_for(1s);
+	}
+
+	cout << "Cleaning up..." << endl;
+
+	dataChannelMap.clear();
+	peerConnectionMap.clear();
+	return 0;
+}
+
+// Create and setup a PeerConnection
+shared_ptr<PeerConnection> createPeerConnection(const Configuration &config,
+                                                weak_ptr<WebSocket> wws, string id) {
+	auto pc = make_shared<PeerConnection>(config);
+
+	pc->onStateChange([](PeerConnection::State state) { cout << "State: " << state << endl; });
+
+	pc->onGatheringStateChange(
+	    [](PeerConnection::GatheringState state) { cout << "Gathering State: " << state << endl; });
+
+	pc->onLocalDescription([wws, id](const Description &description) {
+		json message = {
+		    {"id", id}, {"type", description.typeString()}, {"description", string(description)}};
+
+		if (auto ws = wws.lock())
+			ws->send(message.dump());
+	});
+
+	pc->onLocalCandidate([wws, id](const Candidate &candidate) {
+		json message = {{"id", id},
+		                {"type", "candidate"},
+		                {"candidate", string(candidate)},
+		                {"mid", candidate.mid()}};
+
+		if (auto ws = wws.lock())
+			ws->send(message.dump());
+	});
+
+	pc->onDataChannel([id](shared_ptr<DataChannel> dc) {
+		cout << "DataChannel from " << id << " received with label \"" << dc->label() << "\""
+		     << endl;
+
+		dc->onClosed([id]() { cout << "DataChannel from " << id << " closed" << endl; });
+
+		dc->onMessage([id](const variant<binary, string> &message) {
+			if (!holds_alternative<string>(message))
+				return;
+
+			cout << "Message from " << id << " received: " << get<string>(message) << endl;
+		});
+
+		dc->send("Hello from " + localId);
+
+		dataChannelMap.emplace(id, dc);
+	});
+
+	peerConnectionMap.emplace(id, pc);
+	return pc;
+};
+
+// Helper function to generate a random ID
+string randomId(size_t length) {
+	static const string characters(
+	    "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz");
+	string id(length, '0');
+	default_random_engine rng(random_device{}());
+	uniform_int_distribution<int> dist(0, characters.size() - 1);
+	generate(id.begin(), id.end(), [&]() { return characters.at(dist(rng)); });
+	return id;
+}

examples/copy-paste-capi/CMakeLists.txt

@@ -0,0 +1,15 @@
+cmake_minimum_required(VERSION 3.5.1)
+project(offerer C)
+
+set(CMAKE_C_STANDARD 11)
+set(CMAKE_C_FLAGS "-Wall -g -O2")
+
+add_executable(datachannel-copy-paste-capi-offerer offerer.c)
+set_target_properties(datachannel-copy-paste-capi-offerer PROPERTIES
+	OUTPUT_NAME offerer)
+target_link_libraries(datachannel-copy-paste-capi-offerer datachannel)
+
+add_executable(datachannel-copy-paste-capi-answerer answerer.c)
+set_target_properties(datachannel-copy-paste-capi-answerer PROPERTIES
+	OUTPUT_NAME answerer)
+target_link_libraries(datachannel-copy-paste-capi-answerer datachannel)

examples/copy-paste-capi/answerer.c

@@ -0,0 +1,317 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ * Copyright (c) 2020 Stevedan Ogochukwu Omodolor
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <rtc/rtc.h>
+
+#include <ctype.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifdef _WIN32
+#include "getline.h"
+#include <windows.h>
+static void sleep(unsigned int secs) { Sleep(secs * 1000); }
+#else
+#include <unistd.h> // for sleep
+#endif
+
+typedef struct {
+        rtcState state;
+        rtcGatheringState gatheringState;
+        int pc;
+        int dc;
+        bool connected;
+} Peer;
+
+Peer *peer = NULL;
+
+static void dataChannelCallback(int dc, void *ptr);
+
+static void descriptionCallback(const char *sdp, const char *type, void *ptr);
+
+static void candidateCallback(const char *cand, const char *mid, void *ptr);
+
+static void stateChangeCallback(rtcState state, void *ptr);
+
+static void gatheringStateCallback(rtcGatheringState state, void *ptr);
+
+static void closedCallback(void *ptr);
+
+static void messageCallback(const char *message, int size, void *ptr);
+
+static void deletePeer(Peer *peer);
+
+int all_space(const char *str);
+char* state_print(rtcState state);
+char* rtcGatheringState_print(rtcState state);
+
+int main(int argc, char **argv) {
+        rtcInitLogger(RTC_LOG_DEBUG);
+
+        // Create peer
+        rtcConfiguration config;
+        memset(&config, 0, sizeof(config));
+
+        Peer *peer = (Peer *)malloc(sizeof(Peer));
+        if (!peer) {
+		    fprintf(stderr, "Error allocating memory for peer\n");
+		    return -1;
+	    }
+        memset(peer, 0, sizeof(Peer));
+
+        printf("Peer created\n");
+
+        // Create peer connection
+        peer->pc = rtcCreatePeerConnection(&config);
+
+        rtcSetUserPointer(peer->pc, peer);
+        rtcSetLocalDescriptionCallback(peer->pc, descriptionCallback);
+        rtcSetLocalCandidateCallback(peer->pc, candidateCallback);
+        rtcSetStateChangeCallback(peer->pc, stateChangeCallback);
+        rtcSetGatheringStateChangeCallback(peer->pc, gatheringStateCallback);
+
+        rtcSetUserPointer(peer->dc, NULL);
+        rtcSetDataChannelCallback(peer->pc, dataChannelCallback);
+
+	    sleep(1);
+
+	    bool exit = false;
+        while (!exit) {
+                printf("\n");
+                printf("***************************************************************************************\n");
+                printf("* 0: Exit /"
+                       " 1: Enter remote description /"
+                       " 2: Enter remote candidate /"
+                       " 3: Send message /"
+                       " 4: Print Connection Info *\n"
+                       "[Command]: ");
+
+                int command = -1;
+                int c;
+
+		        if (!scanf("%d", &command)) {
+			        break;
+		        }
+
+		        while ((c = getchar()) != '\n' && c != EOF) {
+		        }
+		        fflush(stdin);
+
+		        switch (command) {
+                case 0: {
+                        exit = true;
+                        break;
+                }
+                case 1: {
+                        // Parse Description
+                        printf("[Description]: ");
+                        char *line = NULL;
+                        size_t len = 0;
+                        size_t read = 0;
+                        char *sdp = (char*) malloc(sizeof(char));
+                        while ((read = getline(&line, &len, stdin)) != -1 && !all_space(line)) {
+                                sdp = (char*) realloc (sdp,(strlen(sdp)+1) +strlen(line)+1);
+                                strcat(sdp, line);
+
+                        }
+                        printf("%s\n",sdp);
+                        rtcSetRemoteDescription(peer->pc, sdp, "offer");
+                        free(sdp);
+                        free(line);
+                        break;
+
+                }
+                case 2: {
+                        // Parse Candidate
+                        printf("[Candidate]: ");
+                        char* candidate = NULL;
+                        size_t candidate_size = 0;
+
+                        if(getline(&candidate, &candidate_size, stdin)) {
+                                rtcAddRemoteCandidate(peer->pc, candidate, "0");
+                                free(candidate);
+
+			            } else {
+				            printf("Error reading line\n");
+				            break;
+			            }
+
+			            break;
+                }
+                case 3: {
+                        // Send Message
+                        if(!peer->connected) {
+                                printf("** Channel is not Open **");
+                                break;
+                        }
+                        printf("[Message]: ");
+                        char* message = NULL;
+                        size_t message_size = 0;
+
+                        if(getline(&message, &message_size, stdin)) {
+                                rtcSendMessage(peer->dc, message, -1);
+                                free(message);
+			            } else {
+				            printf("Error reading line\n");
+				            break;
+			            }
+			            break;
+                }
+                case 4: {
+                        // Connection Info
+                        if(!peer->connected) {
+                                printf("** Channel is not Open **");
+                                break;
+                        }
+                        char buffer[256];
+                        if (rtcGetLocalAddress(peer->pc, buffer, 256) >= 0)
+                                printf("Local address 1:  %s\n", buffer);
+                        if (rtcGetRemoteAddress(peer->pc, buffer, 256) >= 0)
+                                printf("Remote address 1: %s\n", buffer);
+
+                        else
+                                printf("Could not get Candidate Pair Info\n");
+                        break;
+                }
+                default: {
+                        printf("** Invalid Command **");
+                        break;
+                }
+                }
+        }
+
+        deletePeer(peer);
+        return 0;
+}
+
+static void descriptionCallback(const char *sdp, const char *type, void *ptr) {
+        // Peer *peer = (Peer *)ptr;
+        printf("Description %s:\n%s\n", "answerer", sdp);
+}
+
+static void candidateCallback(const char *cand, const char *mid, void *ptr) {
+        // Peer *peer = (Peer *)ptr;
+        printf("Candidate %s: %s\n", "answerer", cand);
+
+}
+
+static void stateChangeCallback(rtcState state, void *ptr) {
+        Peer *peer = (Peer *)ptr;
+        peer->state = state;
+        printf("State %s: %s\n", "answerer", state_print(state));
+}
+
+static void gatheringStateCallback(rtcGatheringState state, void *ptr) {
+        Peer *peer = (Peer *)ptr;
+        peer->gatheringState = state;
+        printf("Gathering state %s: %s\n", "answerer", rtcGatheringState_print(state));
+}
+
+static void closedCallback(void *ptr) {
+        Peer *peer = (Peer *)ptr;
+        peer->connected = false;
+}
+
+static void messageCallback(const char *message, int size, void *ptr) {
+        if (size < 0) { // negative size indicates a null-terminated string
+                printf("Message %s: %s\n", "answerer", message);
+        } else {
+                printf("Message %s: [binary of size %d]\n", "answerer", size);
+        }
+}
+
+static void deletePeer(Peer *peer) {
+        if (peer) {
+                if (peer->dc)
+                        rtcDeleteDataChannel(peer->dc);
+                if (peer->pc)
+                        rtcDeletePeerConnection(peer->pc);
+                free(peer);
+        }
+}
+
+static void dataChannelCallback(int dc, void *ptr) {
+        Peer *peer = (Peer *)ptr;
+        peer->dc = dc;
+        peer->connected = true;
+        rtcSetClosedCallback(dc, closedCallback);
+        rtcSetMessageCallback(dc, messageCallback);
+        char buffer[256];
+        if (rtcGetDataChannelLabel(dc, buffer, 256) >= 0)
+                printf("DataChannel %s: Received with label \"%s\"\n", "answerer", buffer);
+}
+
+int all_space(const char *str) {
+        while (*str) {
+                if (!isspace(*str++)) {
+                        return 0;
+                }
+        }
+
+	    return 1;
+}
+
+char* state_print(rtcState state) {
+        char *str = NULL;
+        switch (state) {
+        case RTC_NEW:
+                str = "RTC_NEW";
+                break;
+        case RTC_CONNECTING:
+                str = "RTC_CONNECTING";
+                break;
+        case RTC_CONNECTED:
+                str = "RTC_CONNECTED";
+                break;
+        case RTC_DISCONNECTED:
+                str = "RTC_DISCONNECTED";
+                break;
+        case RTC_FAILED:
+                str = "RTC_FAILED";
+                break;
+        case RTC_CLOSED:
+                str = "RTC_CLOSED";
+                break;
+        default:
+                break;
+        }
+
+        return str;
+}
+
+char* rtcGatheringState_print(rtcState state) {
+        char* str = NULL;
+        switch (state) {
+        case RTC_GATHERING_NEW:
+                str = "RTC_GATHERING_NEW";
+                break;
+        case RTC_GATHERING_INPROGRESS:
+                str = "RTC_GATHERING_INPROGRESS";
+                break;
+        case RTC_GATHERING_COMPLETE:
+                str = "RTC_GATHERING_COMPLETE";
+                break;
+        default:
+                break;
+        }
+
+        return str;
+}

examples/copy-paste-capi/getline.h

@@ -0,0 +1,48 @@
+// Simple POSIX getline() implementation
+// This code is public domain
+
+#include "malloc.h"
+#include "stdio.h"
+
+ssize_t getline(char **lineptr, size_t *n, FILE *stream) {
+	if (!lineptr || !stream || !n)
+		return -1;
+
+	int c = getc(stream);
+	if (c == EOF)
+		return -1;
+
+	if (!*lineptr) {
+		*lineptr = malloc(128);
+		if (!*lineptr)
+			return -1;
+
+		*n = 128;
+	}
+
+	size_t pos = 0;
+	while(c != EOF) {
+        if (pos + 1 >= *n) {
+            size_t new_size = *n + (*n >> 2);
+			if (new_size < 128)
+				new_size = 128;
+
+			char *new_ptr = realloc(*lineptr, new_size);
+			if (!new_ptr)
+				return -1;
+
+			*n = new_size;
+            *lineptr = new_ptr;
+        }
+
+        ((unsigned char *)(*lineptr))[pos ++] = c;
+		if (c == '\n')
+			break;
+
+		c = getc(stream);
+    }
+
+    (*lineptr)[pos] = '\0';
+    return pos;
+}
+

examples/copy-paste-capi/offerer.c

@@ -0,0 +1,322 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ * Copyright (c) 2020 Stevedan Ogochukwu Omodolor
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <rtc/rtc.h>
+
+#include <ctype.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifdef _WIN32
+#include "getline.h"
+#include <windows.h>
+static void sleep(unsigned int secs) { Sleep(secs * 1000); }
+#else
+#include <unistd.h> // for sleep
+#endif
+
+char* state_print(rtcState state);
+char* rtcGatheringState_print(rtcState state);
+
+typedef struct {
+        rtcState state;
+        rtcGatheringState gatheringState;
+        int pc;
+        int dc;
+        bool connected;
+} Peer;
+
+Peer *peer = NULL;
+
+static void descriptionCallback(const char *sdp, const char *type, void *ptr);
+
+static void candidateCallback(const char *cand, const char *mid, void *ptr);
+
+static void stateChangeCallback(rtcState state, void *ptr);
+
+static void gatheringStateCallback(rtcGatheringState state, void *ptr);
+
+static void openCallback(void *ptr);
+
+static void closedCallback(void *ptr);
+
+static void messageCallback(const char *message, int size, void *ptr);
+
+static void deletePeer(Peer *peer);
+
+int all_space(const char *str);
+
+int main(int argc, char **argv){
+        rtcInitLogger(RTC_LOG_DEBUG);
+
+        // Create peer
+        rtcConfiguration config;
+        memset(&config, 0, sizeof(config));
+
+        Peer *peer = (Peer *)malloc(sizeof(Peer));
+	    if (!peer) {
+		    fprintf(stderr, "Error allocating memory for peer\n");
+		    return -1;
+	    }
+	    memset(peer, 0, sizeof(Peer));
+
+        printf("Peer created\n");
+
+        // Create peer connection
+        peer->pc = rtcCreatePeerConnection(&config);
+        rtcSetUserPointer(peer->pc, peer);
+        rtcSetLocalDescriptionCallback(peer->pc, descriptionCallback);
+        rtcSetLocalCandidateCallback(peer->pc, candidateCallback);
+        rtcSetStateChangeCallback(peer->pc, stateChangeCallback);
+        rtcSetGatheringStateChangeCallback(peer->pc, gatheringStateCallback);
+
+        // Since this is the offere, we will create a datachannel
+        peer->dc = rtcCreateDataChannel(peer->pc, "test");
+        rtcSetOpenCallback(peer->dc, openCallback);
+        rtcSetClosedCallback(peer->dc, closedCallback);
+        rtcSetMessageCallback(peer->dc, messageCallback);
+
+	    sleep(1);
+
+	    bool exit = false;
+        while (!exit) {
+
+                printf("\n");
+                printf("***************************************************************************************\n");
+                printf("* 0: Exit /"
+                       " 1: Enter remote description /"
+                       " 2: Enter remote candidate /"
+                       " 3: Send message /"
+                       " 4: Print Connection Info *\n"
+                       "[Command]: ");
+
+                int command = -1;
+                int c;
+
+		        if (!scanf("%d", &command)) {
+			        break;
+		        }
+
+		        while ((c = getchar()) != '\n' && c != EOF) {
+		        }
+		        fflush(stdin);
+
+                switch (command) {
+                case 0: {
+                        exit = true;
+                        break;
+                }
+                case 1: {
+                        // Parse Description
+                        printf("[Description]: ");
+
+
+                        char *line = NULL;
+                        size_t len = 0;
+                        size_t read = 0;
+                        char *sdp = (char*) malloc(sizeof(char));
+                        while ((read = getline(&line, &len, stdin)) != -1 && !all_space(line)) {
+                                sdp = (char*) realloc (sdp,(strlen(sdp)+1) +strlen(line)+1);
+                                strcat(sdp, line);
+
+                        }
+                        printf("%s\n",sdp);
+                        rtcSetRemoteDescription(peer->pc, sdp, "answer");
+                        free(sdp);
+                        free(line);
+                        break;
+
+                }
+                case 2: {
+                        // Parse Candidate
+                        printf("[Candidate]: ");
+                        char* candidate = NULL;
+                        size_t candidate_size = 0;
+                        if(getline(&candidate, &candidate_size, stdin)) {
+                                rtcAddRemoteCandidate(peer->pc, candidate, "0");
+                                free(candidate);
+
+                        }else {
+                                printf("Error reading line\n");
+                                break;
+                        }
+
+
+                        break;
+                }
+                case 3: {
+                        // Send Message
+                        if(!peer->connected) {
+                                printf("** Channel is not Open **");
+                                break;
+                        }
+                        printf("[Message]: ");
+                        char* message = NULL;
+                        size_t message_size = 0;
+                        if(getline(&message, &message_size, stdin)) {
+                                rtcSendMessage(peer->dc, message, -1);
+                                free(message);
+                        }else {
+                                printf("Error reading line\n");
+                                break;
+                        }
+
+                        break;
+                }
+                case 4: {
+                        // Connection Info
+                        if(!peer->connected) {
+                                printf("** Channel is not Open **");
+                                break;
+                        }
+                        char buffer[256];
+                        if (rtcGetLocalAddress(peer->pc, buffer, 256) >= 0)
+                                printf("Local address 1:  %s\n", buffer);
+                        if (rtcGetRemoteAddress(peer->pc, buffer, 256) >= 0)
+                                printf("Remote address 1: %s\n", buffer);
+
+                        else
+                                printf("Could not get Candidate Pair Info\n");
+                        break;
+                }
+                default: {
+                        printf("** Invalid Command **");
+                        break;
+                }
+                }
+        }
+
+        deletePeer(peer);
+        return 0;
+}
+
+static void descriptionCallback(const char *sdp, const char *type, void *ptr) {
+        // Peer *peer = (Peer *)ptr;
+        printf("Description %s:\n%s\n", "offerer", sdp);
+}
+
+static void candidateCallback(const char *cand, const char *mid, void *ptr) {
+        // Peer *peer = (Peer *)ptr;
+        printf("Candidate %s: %s\n", "offerer", cand);
+
+}
+
+static void stateChangeCallback(rtcState state, void *ptr) {
+        Peer *peer = (Peer *)ptr;
+        peer->state = state;
+        printf("State %s: %s\n", "offerer", state_print(state));
+}
+
+static void gatheringStateCallback(rtcGatheringState state, void *ptr) {
+        Peer *peer = (Peer *)ptr;
+        peer->gatheringState = state;
+        printf("Gathering state %s: %s\n", "offerer", rtcGatheringState_print(state));
+}
+
+static void openCallback(void *ptr) {
+        Peer *peer = (Peer *)ptr;
+        peer->connected = true;
+        char buffer[256];
+        if (rtcGetDataChannelLabel(peer->dc, buffer, 256) >= 0)
+                printf("DataChannel %s: Received with label \"%s\"\n","offerer", buffer);
+}
+
+static void closedCallback(void *ptr) {
+        Peer *peer = (Peer *)ptr;
+        peer->connected = false;
+}
+
+static void messageCallback(const char *message, int size, void *ptr) {
+        // Peer *peer = (Peer *)ptr;
+        if (size < 0) { // negative size indicates a null-terminated string
+                printf("Message %s: %s\n", "offerer", message);
+        } else {
+                printf("Message %s: [binary of size %d]\n", "offerer", size);
+        }
+}
+
+static void deletePeer(Peer *peer) {
+        if (peer) {
+                if (peer->dc)
+                        rtcDeleteDataChannel(peer->dc);
+                if (peer->pc)
+                        rtcDeletePeerConnection(peer->pc);
+                free(peer);
+        }
+}
+
+int all_space(const char *str) {
+        while (*str) {
+                if (!isspace(*str++)) {
+                        return 0;
+                }
+        }
+
+	    return 1;
+}
+
+char* state_print(rtcState state) {
+        char *str = NULL;
+        switch (state) {
+        case RTC_NEW:
+                str = "RTC_NEW";
+                break;
+        case RTC_CONNECTING:
+                str = "RTC_CONNECTING";
+                break;
+        case RTC_CONNECTED:
+                str = "RTC_CONNECTED";
+                break;
+        case RTC_DISCONNECTED:
+                str = "RTC_DISCONNECTED";
+                break;
+        case RTC_FAILED:
+                str = "RTC_FAILED";
+                break;
+        case RTC_CLOSED:
+                str = "RTC_CLOSED";
+                break;
+        default:
+                break;
+        }
+
+        return str;
+
+}
+
+char* rtcGatheringState_print(rtcState state) {
+        char* str = NULL;
+        switch (state) {
+        case RTC_GATHERING_NEW:
+                str = "RTC_GATHERING_NEW";
+                break;
+        case RTC_GATHERING_INPROGRESS:
+                str = "RTC_GATHERING_INPROGRESS";
+                break;
+        case RTC_GATHERING_COMPLETE:
+                str = "RTC_GATHERING_COMPLETE";
+                break;
+        default:
+                break;
+        }
+
+        return str;
+}

examples/copy-paste/CMakeLists.txt

@@ -0,0 +1,14 @@
+cmake_minimum_required(VERSION 3.7)
+
+add_executable(datachannel-copy-paste-offerer offerer.cpp)
+set_target_properties(datachannel-copy-paste-offerer PROPERTIES
+	CXX_STANDARD 17
+	OUTPUT_NAME offerer)
+target_link_libraries(datachannel-copy-paste-offerer datachannel)
+
+add_executable(datachannel-copy-paste-answerer answerer.cpp)
+set_target_properties(datachannel-copy-paste-answerer PROPERTIES
+	CXX_STANDARD 17
+	OUTPUT_NAME answerer)
+target_link_libraries(datachannel-copy-paste-answerer datachannel)
+

examples/copy-paste/README.md

@@ -0,0 +1,9 @@
+* Execute ```offerer``` app in console
+* Execute ```answerer``` app in another console
+* Copy "Local Description" from ```offerer```
+* Enter 1 to ```answerer```
+* Paste copied description, press enter
+* Redo same procedure for ```answerer```
+* Redo same procedure for candidates
+* Wait for "DataChannel open" message
+* Send message from one peer to another

examples/copy-paste/answerer.cpp

@@ -0,0 +1,159 @@
+/**
+ * Copyright (c) 2019 Paul-Louis Ageneau, Murat Dogan
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "rtc/rtc.hpp"
+
+#include <chrono>
+#include <iostream>
+#include <memory>
+#include <thread>
+
+using namespace rtc;
+using namespace std;
+
+template <class T> weak_ptr<T> make_weak_ptr(shared_ptr<T> ptr) { return ptr; }
+
+int main(int argc, char **argv) {
+	rtc::InitLogger(LogLevel::Warning);
+
+	Configuration config;
+	// config.iceServers.emplace_back("stun.l.google.com:19302");
+
+	auto pc = std::make_shared<PeerConnection>(config);
+
+	pc->onLocalDescription([](const Description &description) {
+		cout << "Local Description (Paste this to the other peer):" << endl;
+		cout << string(description) << endl;
+	});
+
+	pc->onLocalCandidate([](const Candidate &candidate) {
+		cout << "Local Candidate (Paste this to the other peer after the local description):"
+		     << endl;
+		cout << string(candidate) << endl << endl;
+	});
+
+	pc->onStateChange(
+	    [](PeerConnection::State state) { cout << "[State: " << state << "]" << endl; });
+	pc->onGatheringStateChange([](PeerConnection::GatheringState state) {
+		cout << "[Gathering State: " << state << "]" << endl;
+	});
+
+	shared_ptr<DataChannel> dc = nullptr;
+	pc->onDataChannel([&](shared_ptr<DataChannel> _dc) {
+		cout << "[Got a DataChannel with label: " << _dc->label() << "]" << endl;
+		dc = _dc;
+
+		dc->onClosed([&]() { cout << "[DataChannel closed: " << dc->label() << "]" << endl; });
+
+		dc->onMessage([](const variant<binary, string> &message) {
+			if (holds_alternative<string>(message)) {
+				cout << "[Received message: " << get<string>(message) << "]" << endl;
+			}
+		});
+	});
+
+	bool exit = false;
+	while (!exit) {
+		cout << endl
+		     << "**********************************************************************************"
+		        "*****"
+		     << endl
+		     << "* 0: Exit /"
+		     << " 1: Enter remote description /"
+		     << " 2: Enter remote candidate /"
+		     << " 3: Send message /"
+		     << " 4: Print Connection Info *" << endl
+		     << "[Command]: ";
+
+		int command = -1;
+		cin >> command;
+		cin.ignore();
+
+		switch (command) {
+		case 0: {
+			exit = true;
+			break;
+		}
+		case 1: {
+			// Parse Description
+			cout << "[Description]: ";
+			string sdp, line;
+			while (getline(cin, line) && !line.empty()) {
+				sdp += line;
+				sdp += "\r\n";
+			}
+			std::cout << sdp;
+			pc->setRemoteDescription(sdp);
+			break;
+		}
+		case 2: {
+			// Parse Candidate
+			cout << "[Candidate]: ";
+			string candidate;
+			getline(cin, candidate);
+			pc->addRemoteCandidate(candidate);
+			break;
+		}
+		case 3: {
+			// Send Message
+			if (!dc || !dc->isOpen()) {
+				cout << "** Channel is not Open ** ";
+				break;
+			}
+			cout << "[Message]: ";
+			string message;
+			getline(cin, message);
+			dc->send(message);
+			break;
+		}
+		case 4: {
+			// Connection Info
+			if (!dc || !dc->isOpen()) {
+				cout << "** Channel is not Open ** ";
+				break;
+			}
+			CandidateInfo local, remote;
+			std::optional<std::chrono::milliseconds> rtt = pc->rtt();
+			if (pc->getSelectedCandidatePair(&local, &remote)) {
+				cout << "Local: " << local.address << ":" << local.port << " " << local.type << " "
+				     << local.transportType << endl;
+				cout << "Remote: " << remote.address << ":" << remote.port << " " << remote.type
+				     << " " << remote.transportType << endl;
+				cout << "Bytes Sent:" << pc->bytesSent()
+				     << " / Bytes Received:" << pc->bytesReceived() << " / Round-Trip Time:";
+				if (rtt.has_value())
+					cout << rtt.value().count();
+				else
+					cout << "null";
+				cout << " ms";
+			} else
+				cout << "Could not get Candidate Pair Info" << endl;
+			break;
+		}
+		default: {
+			cout << "** Invalid Command ** ";
+			break;
+		}
+		}
+	}
+
+	if (dc)
+		dc->close();
+	if (pc)
+		pc->close();
+}

examples/copy-paste/offerer.cpp

@@ -0,0 +1,159 @@
+/**
+ * Copyright (c) 2019 Paul-Louis Ageneau, Murat Dogan
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "rtc/rtc.hpp"
+
+#include <chrono>
+#include <iostream>
+#include <memory>
+#include <thread>
+
+using namespace rtc;
+using namespace std;
+
+template <class T> weak_ptr<T> make_weak_ptr(shared_ptr<T> ptr) { return ptr; }
+
+int main(int argc, char **argv) {
+	rtc::InitLogger(LogLevel::Warning);
+
+	Configuration config;
+	// config.iceServers.emplace_back("stun.l.google.com:19302");
+
+	auto pc = std::make_shared<PeerConnection>(config);
+
+	pc->onLocalDescription([](const Description &description) {
+		cout << "Local Description (Paste this to the other peer):" << endl;
+		cout << string(description) << endl;
+	});
+
+	pc->onLocalCandidate([](const Candidate &candidate) {
+		cout << "Local Candidate (Paste this to the other peer after the local description):"
+		     << endl;
+		cout << string(candidate) << endl << endl;
+	});
+
+	pc->onStateChange(
+	    [](PeerConnection::State state) { cout << "[State: " << state << "]" << endl; });
+
+	pc->onGatheringStateChange([](PeerConnection::GatheringState state) {
+		cout << "[Gathering State: " << state << "]" << endl;
+	});
+
+	auto dc = pc->createDataChannel("test"); // this is the offerer, so create a data channel
+
+	dc->onOpen([&]() { cout << "[DataChannel open: " << dc->label() << "]" << endl; });
+
+	dc->onClosed([&]() { cout << "[DataChannel closed: " << dc->label() << "]" << endl; });
+
+	dc->onMessage([](const variant<binary, string> &message) {
+		if (holds_alternative<string>(message)) {
+			cout << "[Received: " << get<string>(message) << "]" << endl;
+		}
+	});
+
+	this_thread::sleep_for(1s);
+
+	bool exit = false;
+	while (!exit) {
+		cout << endl
+		     << "**********************************************************************************"
+		        "*****"
+		     << endl
+		     << "* 0: Exit /"
+		     << " 1: Enter remote description /"
+		     << " 2: Enter remote candidate /"
+		     << " 3: Send message /"
+		     << " 4: Print Connection Info *" << endl
+		     << "[Command]: ";
+
+		int command = -1;
+		cin >> command;
+		cin.ignore();
+
+		switch (command) {
+		case 0: {
+			exit = true;
+			break;
+		}
+		case 1: {
+			// Parse Description
+			cout << "[Description]: ";
+			string sdp, line;
+			while (getline(cin, line) && !line.empty()) {
+				sdp += line;
+				sdp += "\r\n";
+			}
+			pc->setRemoteDescription(sdp);
+			break;
+		}
+		case 2: {
+			// Parse Candidate
+			cout << "[Candidate]: ";
+			string candidate;
+			getline(cin, candidate);
+			pc->addRemoteCandidate(candidate);
+			break;
+		}
+		case 3: {
+			// Send Message
+			if (!dc->isOpen()) {
+				cout << "** Channel is not Open ** ";
+				break;
+			}
+			cout << "[Message]: ";
+			string message;
+			getline(cin, message);
+			dc->send(message);
+			break;
+		}
+		case 4: {
+			// Connection Info
+			if (!dc || !dc->isOpen()) {
+				cout << "** Channel is not Open ** ";
+				break;
+			}
+			CandidateInfo local, remote;
+			std::optional<std::chrono::milliseconds> rtt = pc->rtt();
+			if (pc->getSelectedCandidatePair(&local, &remote)) {
+				cout << "Local: " << local.address << ":" << local.port << " " << local.type << " "
+				     << local.transportType << endl;
+				cout << "Remote: " << remote.address << ":" << remote.port << " " << remote.type
+				     << " " << remote.transportType << endl;
+				cout << "Bytes Sent:" << pc->bytesSent()
+				     << " / Bytes Received:" << pc->bytesReceived() << " / Round-Trip Time:";
+				if (rtt.has_value())
+					cout << rtt.value().count();
+				else
+					cout << "null";
+				cout << " ms";
+			} else
+				cout << "Could not get Candidate Pair Info" << endl;
+			break;
+		}
+		default: {
+			cout << "** Invalid Command ** ";
+			break;
+		}
+		}
+	}
+
+	if (dc)
+		dc->close();
+	if (pc)
+		pc->close();
+}

examples/signaling-server-python/LICENSE

@@ -0,0 +1,661 @@
+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The GNU Affero General Public License is a free, copyleft license for
+software and other kinds of works, specifically designed to ensure
+cooperation with the community in the case of network server software.
+
+  The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+our General Public Licenses are intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+  Developers that use our General Public Licenses protect your rights
+with two steps: (1) assert copyright on the software, and (2) offer
+you this License which gives you legal permission to copy, distribute
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+  A secondary benefit of defending all users' freedom is that
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+software used on network servers, this result may fail to come about.
+The GNU General Public License permits making a modified version and
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+source code to the public.
+
+  The GNU Affero General Public License is designed specifically to
+ensure that, in such cases, the modified source code becomes available
+to the community.  It requires the operator of a network server to
+provide the source code of the modified version running there to the
+users of that server.  Therefore, public use of a modified version, on
+a publicly accessible server, gives the public access to the source
+code of the modified version.
+
+  An older license, called the Affero General Public License and
+published by Affero, was designed to accomplish similar goals.  This is
+a different license, not a version of the Affero GPL, but Affero has
+released a new version of the Affero GPL which permits relicensing under
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+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
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+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
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+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published
+    by the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+
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+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
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+
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+interface could display a "Source" link that leads users to an archive
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+specific requirements.
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+<http://www.gnu.org/licenses/>.

examples/signaling-server-python/signaling-server.py

@@ -0,0 +1,78 @@
+#!/usr/bin/env python
+#
+# Signaling server example for libdatachannel
+# Copyright (c) 2020 Paul-Louis Ageneau
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import sys
+import ssl
+import json
+import asyncio
+import logging
+import websockets
+
+
+logger = logging.getLogger('websockets')
+logger.setLevel(logging.INFO)
+logger.addHandler(logging.StreamHandler(sys.stdout))
+
+clients = {}
+
+
+async def handle_websocket(websocket, path):
+    client_id = None
+    try:
+        splitted = path.split('/')
+        splitted.pop(0)
+        client_id = splitted.pop(0)
+        print('Client {} connected'.format(client_id))
+
+        clients[client_id] = websocket
+        while True:
+            data = await websocket.recv()
+            print('Client {} << {}'.format(client_id, data))
+            message = json.loads(data)
+            destination_id = message['id']
+            destination_websocket = clients.get(destination_id)
+            if destination_websocket:
+                message['id'] = client_id
+                data = json.dumps(message)
+                print('Client {} >> {}'.format(destination_id, data))
+                await destination_websocket.send(data)
+            else:
+                print('Client {} not found'.format(destination_id))
+
+    except Exception as e:
+        print(e)
+
+    finally:
+        if client_id:
+            del clients[client_id]
+            print('Client {} disconnected'.format(client_id))
+
+if __name__ == '__main__':
+    port = int(sys.argv[1]) if len(sys.argv) > 1 else 8000
+    ssl_cert = sys.argv[2] if len(sys.argv) > 2 else None
+
+    if ssl_cert:
+        ssl_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
+        ssl_context.load_cert_chain(ssl_cert)
+    else:
+        ssl_context = None
+
+    print('Listening on port {}'.format(port))
+    start_server = websockets.serve(handle_websocket, '127.0.0.1', port, ssl=ssl_context)
+    asyncio.get_event_loop().run_until_complete(start_server)
+    asyncio.get_event_loop().run_forever()

examples/signaling-server-rust/.gitignore

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examples/signaling-server-rust/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "webrtc_server"
+version = "0.1.0"
+authors = ["Nico Chatzi <nico.chatzigianis@focusrite.com>"]
+edition = "2018"
+
+[dependencies]
+rocket = "0.4.4"
+rocket_cors = "0.5.0"
+serde = "1.0"
+serde_json = "1.0"
+serde_derive = "1.0"
+bincode = "1.2.1"
+
+[dependencies.rocket_contrib]
+version = "0.4.4"
+default-features = false
+features = ["json"]

examples/signaling-server-rust/src/main.rs

@@ -0,0 +1,147 @@
+#![feature(proc_macro_hygiene, decl_macro)]
+
+#[macro_use]
+extern crate rocket;
+extern crate rocket_cors;
+#[macro_use]
+extern crate rocket_contrib;
+#[macro_use]
+extern crate serde_derive;
+
+extern crate bincode;
+
+use std::sync::Mutex;
+
+use rocket_contrib::json::{Json, JsonValue};
+
+use rocket::http::Method; // 1.
+
+use rocket_cors::{
+    AllowedHeaders, AllowedOrigins, Error, // 2.
+    Cors, CorsOptions // 3.
+};
+
+fn make_cors() -> Cors {
+    let allowed_origins = AllowedOrigins::some_exact(&[ // 4.
+        "http://localhost:8080",
+        "http://127.0.0.1:8080",
+        "http://localhost:8000",
+        "http://0.0.0.0:8000",
+    ]);
+
+    CorsOptions { // 5.
+        allowed_origins,
+        allowed_methods: vec![Method::Get, Method::Post].into_iter().map(From::from).collect(), // 1.
+        allowed_headers: AllowedHeaders::some(&[
+            "Authorization",
+            "Accept",
+            "Content-Type",
+            "User-Agent",
+            "Access-Control-Allow-Origin", // 6.
+        ]),
+        allow_credentials: true,
+        ..Default::default()
+    }
+    .to_cors()
+    .expect("error while building CORS")
+}
+
+type Data = Mutex<String>;
+
+#[derive(Serialize, Deserialize, Clone, PartialEq, Debug)]
+pub struct ChannelData {
+    pub description: String,
+    pub candidate: String,
+}
+
+impl Default for ChannelData {
+    fn default() -> ChannelData {
+        ChannelData {
+            description: "".to_owned(),
+            candidate: "".to_owned(),
+        }
+    }
+}
+
+#[post("/json", data = "<payload>")]
+fn new(payload: String, state: rocket::State<Data>) -> JsonValue {
+    let mut data = state.lock().expect("state locked");
+    *data = payload;
+    json!({ "status": "ok" })
+}
+
+#[get("/json")]
+fn get(state: rocket::State<Data>) -> Option<String> {
+    let data = state.lock().expect("state locked");
+    Some(data.clone())
+}
+
+#[catch(404)]
+fn not_found() -> JsonValue {
+    json!({
+        "status": "error",
+        "reason": "Resource was not found."
+    })
+}
+
+fn rocket() -> rocket::Rocket {
+    rocket::ignite()
+        .mount("/state", routes![new, get])
+        .register(catchers![not_found])
+        .manage(Mutex::new(String::new()))
+        .attach(make_cors())
+}
+
+fn main() {
+    rocket().launch();
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    use rocket::http::{ContentType, Status};
+    use rocket::local::Client;
+
+    #[test]
+    fn test_save_load() {
+        let data = ChannelData {
+            description: "v=0
+            o=- 3294530454 0 IN IP4 127.0.0.1
+            s=-
+            t=0 0
+            a=group:BUNDLE 0
+            m=application 9 UDP/DTLS/SCTP webrtc-datachannel
+            c=IN IP4 0.0.0.0
+            a=ice-ufrag:ntAX
+            a=ice-pwd:H59OKuJgItlvJZR5E78QYo
+            a=ice-options:trickle
+            a=mid:0
+            a=setup:actpass
+            a=dtls-id:1
+            a=fingerprint:sha-256 72:0E:8D:8C:9F:A2:E4:40:E7:2E:23:EF:F6:E7:89:94:0F:6B:78:9A:36:61:43:2C:6A:45:30:62:CB:68:B3:73
+            a=sctp-port:5000
+            a=max-message-size:262144".to_owned(),
+            candidate: "a=candidate:1 1 UDP 2122317823 10.0.1.83 55100 typ host".to_owned(),
+        };
+        println!("{:?}", data);
+        let client = Client::new(rocket()).unwrap();
+
+        let res = client
+            .post("/state/json")
+            .header(ContentType::JSON)
+            .remote("127.0.0.1:8000".parse().unwrap())
+            .body(serde_json::to_vec(&data).unwrap())
+            .dispatch();
+        assert_eq!(res.status(), Status::Ok);
+
+        let mut res = client
+            .get("/state/json")
+            .header(ContentType::JSON)
+            .dispatch();
+        assert_eq!(res.status(), Status::Ok);
+
+        let body = res.body().unwrap().into_string().unwrap();
+        println!("{}", body);
+    }
+}

examples/web/LICENSE

@@ -0,0 +1,339 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
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+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
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+your programs, too.
+
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+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
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+running the Program is not restricted, and the output from the Program
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+Whether that is true depends on what the Program does.
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+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
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+under Section 2) in object code or executable form under the terms of
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+                     END OF TERMS AND CONDITIONS
+
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+
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+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
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+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
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+
+If the program is interactive, make it output a short notice like this
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+
+    Gnomovision version 69, Copyright (C) year name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
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+
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+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.

examples/web/index.html

@@ -0,0 +1,23 @@
+<!doctype html>
+<html>
+    <head>
+		<meta charset="UTF-8">
+        <title>WebRTC Example</title>
+		<link rel="stylesheet" href="style.css">
+        <script src="script.js"></script>
+    </head>
+    <body>
+        <h1>WebRTC Example</h1>
+        <h2>Local ID</h2>
+        <p id="localId"></p>
+        <h2>Send an offer through signaling</h2>
+		<input type="text" id="offerId" placeholder="remote ID" disabled>
+		<input type="button" id="offerBtn" value="Offer" disabled>
+		<br>
+        <h2>Send a message through DataChannel</h2>
+        <input type="text" id="sendMsg" placeholder="message" disabled>
+        <input type="button" id="sendBtn" value="Send" disabled>
+        <br>
+    </body>
+</html>
+

examples/web/package-lock.json

@@ -0,0 +1,119 @@
+{
+  "name": "libdatachannel-example-web",
+  "version": "0.0.1",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
+    "d": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/d/-/d-1.0.1.tgz",
+      "integrity": "sha512-m62ShEObQ39CfralilEQRjH6oAMtNCV1xJyEx5LpRYUVN+EviphDgUc/F3hnYbADmkiNs67Y+3ylmlG7Lnu+FA==",
+      "requires": {
+        "es5-ext": "^0.10.50",
+        "type": "^1.0.1"
+      }
+    },
+    "debug": {
+      "version": "2.6.9",
+      "resolved": "https://registry.npmjs.org/debug/-/debug-2.6.9.tgz",
+      "integrity": "sha512-bC7ElrdJaJnPbAP+1EotYvqZsb3ecl5wi6Bfi6BJTUcNowp6cvspg0jXznRTKDjm/E7AdgFBVeAPVMNcKGsHMA==",
+      "requires": {
+        "ms": "2.0.0"
+      }
+    },
+    "es5-ext": {
+      "version": "0.10.53",
+      "resolved": "https://registry.npmjs.org/es5-ext/-/es5-ext-0.10.53.tgz",
+      "integrity": "sha512-Xs2Stw6NiNHWypzRTY1MtaG/uJlwCk8kH81920ma8mvN8Xq1gsfhZvpkImLQArw8AHnv8MT2I45J3c0R8slE+Q==",
+      "requires": {
+        "es6-iterator": "~2.0.3",
+        "es6-symbol": "~3.1.3",
+        "next-tick": "~1.0.0"
+      }
+    },
+    "es6-iterator": {
+      "version": "2.0.3",
+      "resolved": "https://registry.npmjs.org/es6-iterator/-/es6-iterator-2.0.3.tgz",
+      "integrity": "sha1-p96IkUGgWpSwhUQDstCg+/qY87c=",
+      "requires": {
+        "d": "1",
+        "es5-ext": "^0.10.35",
+        "es6-symbol": "^3.1.1"
+      }
+    },
+    "es6-symbol": {
+      "version": "3.1.3",
+      "resolved": "https://registry.npmjs.org/es6-symbol/-/es6-symbol-3.1.3.tgz",
+      "integrity": "sha512-NJ6Yn3FuDinBaBRWl/q5X/s4koRHBrgKAu+yGI6JCBeiu3qrcbJhwT2GeR/EXVfylRk8dpQVJoLEFhK+Mu31NA==",
+      "requires": {
+        "d": "^1.0.1",
+        "ext": "^1.1.2"
+      }
+    },
+    "ext": {
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/ext/-/ext-1.4.0.tgz",
+      "integrity": "sha512-Key5NIsUxdqKg3vIsdw9dSuXpPCQ297y6wBjL30edxwPgt2E44WcWBZey/ZvUc6sERLTxKdyCu4gZFmUbk1Q7A==",
+      "requires": {
+        "type": "^2.0.0"
+      },
+      "dependencies": {
+        "type": {
+          "version": "2.0.0",
+          "resolved": "https://registry.npmjs.org/type/-/type-2.0.0.tgz",
+          "integrity": "sha512-KBt58xCHry4Cejnc2ISQAF7QY+ORngsWfxezO68+12hKV6lQY8P/psIkcbjeHWn7MqcgciWJyCCevFMJdIXpow=="
+        }
+      }
+    },
+    "is-typedarray": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/is-typedarray/-/is-typedarray-1.0.0.tgz",
+      "integrity": "sha1-5HnICFjfDBsR3dppQPlgEfzaSpo="
+    },
+    "ms": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/ms/-/ms-2.0.0.tgz",
+      "integrity": "sha1-VgiurfwAvmwpAd9fmGF4jeDVl8g="
+    },
+    "nan": {
+      "version": "2.14.1",
+      "resolved": "https://registry.npmjs.org/nan/-/nan-2.14.1.tgz",
+      "integrity": "sha512-isWHgVjnFjh2x2yuJ/tj3JbwoHu3UC2dX5G/88Cm24yB6YopVgxvBObDY7n5xW6ExmFhJpSEQqFPvq9zaXc8Jw=="
+    },
+    "next-tick": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/next-tick/-/next-tick-1.0.0.tgz",
+      "integrity": "sha1-yobR/ogoFpsBICCOPchCS524NCw="
+    },
+    "type": {
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/type/-/type-1.2.0.tgz",
+      "integrity": "sha512-+5nt5AAniqsCnu2cEQQdpzCAh33kVx8n0VoFidKpB1dVVLAN/F+bgVOqOJqOnEnrhp222clB5p3vUlD+1QAnfg=="
+    },
+    "typedarray-to-buffer": {
+      "version": "3.1.5",
+      "resolved": "https://registry.npmjs.org/typedarray-to-buffer/-/typedarray-to-buffer-3.1.5.tgz",
+      "integrity": "sha512-zdu8XMNEDepKKR+XYOXAVPtWui0ly0NtohUscw+UmaHiAWT8hrV1rr//H6V+0DvJ3OQ19S979M0laLfX8rm82Q==",
+      "requires": {
+        "is-typedarray": "^1.0.0"
+      }
+    },
+    "websocket": {
+      "version": "1.0.31",
+      "resolved": "https://registry.npmjs.org/websocket/-/websocket-1.0.31.tgz",
+      "integrity": "sha512-VAouplvGKPiKFDTeCCO65vYHsyay8DqoBSlzIO3fayrfOgU94lQN5a1uWVnFrMLceTJw/+fQXR5PGbUVRaHshQ==",
+      "requires": {
+        "debug": "^2.2.0",
+        "es5-ext": "^0.10.50",
+        "nan": "^2.14.0",
+        "typedarray-to-buffer": "^3.1.5",
+        "yaeti": "^0.0.6"
+      }
+    },
+    "yaeti": {
+      "version": "0.0.6",
+      "resolved": "https://registry.npmjs.org/yaeti/-/yaeti-0.0.6.tgz",
+      "integrity": "sha1-8m9ITXJoTPQr7ft2lwqhYI+/lXc="
+    }
+  }
+}

examples/web/package.json

@@ -0,0 +1,23 @@
+{
+  "name": "libdatachannel-example-web",
+  "version": "0.0.1",
+  "description": "Example for libdatachannel",
+  "main": "server.js",
+  "scripts": {
+    "start": "node server.js",
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/paullouisageneau/libdatachannel.git"
+  },
+  "author": "Paul-Louis Ageneau",
+  "license": "GPL-2.0",
+  "bugs": {
+    "url": "https://github.com/paullouisageneau/libdatachannel/issues"
+  },
+  "homepage": "https://github.com/paullouisageneau/libdatachannel#readme",
+  "dependencies": {
+    "websocket": "^1.0.31"
+  }
+}

examples/web/script.js

@@ -0,0 +1,194 @@
+/*
+ * libdatachannel example web client
+ * Copyright (C) 2020 Lara Mackey
+ * Copyright (C) 2020 Paul-Louis Ageneau
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+window.addEventListener('load', () => {
+
+const config = {
+  iceServers: [{
+    urls: 'stun:stun.l.google.com:19302', // change to your STUN server
+  }],
+};
+
+const localId = randomId(4);
+
+const url = `ws://localhost:8000/${localId}`;
+
+const peerConnectionMap = {};
+const dataChannelMap = {};
+
+const offerId = document.getElementById('offerId');
+const offerBtn = document.getElementById('offerBtn');
+const sendMsg = document.getElementById('sendMsg');
+const sendBtn = document.getElementById('sendBtn');
+const _localId = document.getElementById('localId');
+_localId.textContent = localId;
+
+console.log('Connecting to signaling...');
+openSignaling(url)
+  .then((ws) => {
+    console.log('WebSocket connected, signaling ready');
+    offerId.disabled = false;
+    offerBtn.disabled = false;
+    offerBtn.onclick = () => offerPeerConnection(ws, offerId.value);
+  })
+  .catch((err) => console.error(err));
+
+
+function openSignaling(url) {
+  return new Promise((resolve, reject) => {
+    const ws = new WebSocket(url);
+    ws.onopen = () => resolve(ws);
+    ws.onerror = () => reject(new Error('WebSocket error'));
+    ws.onclosed = () => console.error('WebSocket disconnected');
+    ws.onmessage = (e) => {
+      if(typeof(e.data) != 'string') return;
+      const message = JSON.parse(e.data);
+      const { id, type } = message;
+
+      let pc = peerConnectionMap[id];
+      if(!pc) {
+		    if(type != 'offer') return;
+
+			  // Create PeerConnection for answer
+			  console.log(`Answering to ${id}`);
+			  pc = createPeerConnection(ws, id);
+		  }
+
+      switch(type) {
+      case 'offer':
+      case 'answer':
+			  pc.setRemoteDescription({
+			    sdp: message.description,
+			    type: message.type,
+			  })
+			  .then(() => {
+          if(type == 'offer') {
+			      // Send answer
+            sendLocalDescription(ws, id, pc, 'answer');
+          }
+			  });
+			  break;
+
+			case 'candidate':
+		    pc.addIceCandidate({
+          candidate: message.candidate,
+          sdpMid: message.mid,
+		    });
+		    break;
+		  }
+    }
+  });
+}
+
+function offerPeerConnection(ws, id) {
+	// Create PeerConnection
+	console.log(`Offering to ${id}`);
+	pc = createPeerConnection(ws, id);
+
+  // Create DataChannel
+  const label = "test";
+  console.log(`Creating DataChannel with label "${label}"`);
+  const dc = pc.createDataChannel(label);
+  setupDataChannel(dc, id);
+
+  // Send offer
+  sendLocalDescription(ws, id, pc, 'offer');
+}
+
+// Create and setup a PeerConnection
+function createPeerConnection(ws, id) {
+  const pc = new RTCPeerConnection(config);
+  pc.onconnectionstatechange = () => console.log(`Connection state: ${pc.connectionState}`);
+  pc.onicegatheringstatechange = () => console.log(`Gathering state: ${pc.iceGatheringState}`);
+  pc.onicecandidate = (e) => {
+    if (e.candidate) {
+      // Send candidate
+      sendLocalCandidate(ws, id, e.candidate);
+    }
+  };
+  pc.ondatachannel = (e) => {
+    const dc = e.channel;
+    console.log(`"DataChannel from ${id} received with label "${dc.label}"`);
+    setupDataChannel(dc, id);
+
+		dc.send(`Hello from ${localId}`);
+
+    sendMsg.disabled = false;
+    sendBtn.disabled = false;
+    sendBtn.onclick = () => dc.send(sendMsg.value);
+  };
+
+  peerConnectionMap[id] = pc;
+  return pc;
+}
+
+// Setup a DataChannel
+function setupDataChannel(dc, id) {
+  dc.onopen = () => {
+    console.log(`DataChannel from ${id} open`);
+
+    sendMsg.disabled = false;
+    sendBtn.disabled = false;
+    sendBtn.onclick = () => dc.send(sendMsg.value);
+  };
+  dc.onclose = () => {
+    console.log(`DataChannel from ${id} closed`);
+  };
+	dc.onmessage = (e) => {
+    if(typeof(e.data) != 'string') return;
+		console.log(`Message from ${id} received: ${e.data}`);
+    document.body.appendChild(document.createTextNode(e.data));
+	};
+
+  dataChannelMap[id] = dc;
+  return dc;
+}
+
+function sendLocalDescription(ws, id, pc, type) {
+  (type == 'offer' ? pc.createOffer() : pc.createAnswer())
+    .then((desc) => pc.setLocalDescription(desc))
+    .then(() => {
+      const { sdp, type } = pc.localDescription;
+      ws.send(JSON.stringify({
+        id,
+        type,
+        description: sdp,
+      }));
+    });
+}
+
+function sendLocalCandidate(ws, id, cand) {
+  const {candidate, sdpMid} = cand;
+  ws.send(JSON.stringify({
+    id,
+    type: 'candidate',
+    candidate,
+    mid: sdpMid,
+  }));
+}
+
+// Helper function to generate a random ID
+function randomId(length) {
+  const characters = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
+  const pickRandom = () => characters.charAt(Math.floor(Math.random() * characters.length));
+  return [...Array(length)].map(pickRandom).join('');
+}
+
+});
+

examples/web/server.js

@@ -0,0 +1,102 @@
+/*
+ * libdatachannel example web server
+ * Copyright (C) 2020 Lara Mackey
+ * Copyright (C) 2020 Paul-Louis Ageneau
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+const fs = require('fs');
+const http = require('http');
+const websocket = require('websocket');
+
+const staticFiles = {
+  '/index.html': 'text/html',
+  '/style.css': 'text/css',
+  '/script.js': 'text/javascript',
+};
+
+const clients = {};
+
+const httpServer = http.createServer((req, res) => {
+  console.log(`${req.method.toUpperCase()} ${req.url}`);
+
+  const respond = (code, data, contentType = 'text/plain') => {
+    res.writeHead(code, {
+      'Content-Type': contentType,
+      'Access-Control-Allow-Origin': '*',
+    });
+    res.end(data);
+  };
+
+  if(req.method != 'GET') {
+    respond(405, 'Method not allowed');
+    return;
+  }
+
+  const url = req.url == '/' ? '/index.html' : req.url;
+  const contentType = staticFiles[url];
+  if(!contentType) {
+    respond(404, 'Not found');
+    return;
+  }
+
+  fs.readFile(__dirname + url, (err, data) => {
+    if(err) {
+      respond(500, 'Missing file');
+      return;
+    }
+
+    respond(200, data, contentType);
+  });
+});
+
+const wsServer = new websocket.server({ httpServer });
+wsServer.on('request', (req) => {
+  console.log(`WS  ${req.resource}`);
+
+  const { path } = req.resourceURL;
+  const splitted = path.split('/');
+  splitted.shift();
+  const id = splitted[0];
+
+  const conn = req.accept(null, req.origin);
+  conn.on('message', (data) => {
+    if(data.type === 'utf8') {
+      console.log(`Client ${id} << ${data.utf8Data}`);
+
+      const message = JSON.parse(data.utf8Data);
+      const destId = message.id;
+      const dest = clients[destId];
+      if(dest) {
+        message.id = id;
+        const data = JSON.stringify(message);
+        console.log(`Client ${destId} >> ${data}`);
+        dest.send(data);
+      }
+      else {
+        console.error(`Client ${destId} not found`);
+      }
+    }
+  });
+  conn.on('close', () => {
+    delete clients[id];
+    console.error(`Client ${id} disconnected`);
+  });
+
+  clients[id] = conn;
+});
+
+httpServer.listen(8000);
+

examples/web/style.css

@@ -0,0 +1,20 @@
+body {
+	font-family: arial, verdana, sans-serif;
+	font-size: 12pt;
+	background-color: #FFFFFF;
+	color: #000000;
+	margin: 0;
+	padding: 0.5em;
+}
+
+input {
+	font-size: 100%;
+	vertical-align: middle;
+}
+
+input[type="text"] {
+	width: 8em;
+	max-width: 75%;
+	padding: 0.4em;
+}
+

include/rtc/candidate.hpp

@@ -25,10 +25,23 @@
 
 namespace rtc {
 
+enum class CandidateType { Host = 0, ServerReflexive, PeerReflexive, Relayed };
+enum class CandidateTransportType { Udp = 0, TcpActive, TcpPassive, TcpSo };
+struct CandidateInfo {
+	string address;
+	int port;
+	CandidateType type;
+	CandidateTransportType transportType;
+};
+
 class Candidate {
 public:
 	Candidate(string candidate, string mid = "");
 
+	enum class ResolveMode { Simple, Lookup };
+	bool resolve(ResolveMode mode = ResolveMode::Simple);
+	bool isResolved() const;
+
 	string candidate() const;
 	string mid() const;
 	operator string() const;
@@ -36,11 +49,14 @@ public:
 private:
 	string mCandidate;
 	string mMid;
+	bool mIsResolved;
 };
 
 } // namespace rtc
 
 std::ostream &operator<<(std::ostream &out, const rtc::Candidate &candidate);
+std::ostream &operator<<(std::ostream &out, const rtc::CandidateType &type);
+std::ostream &operator<<(std::ostream &out, const rtc::CandidateTransportType &transportType);
 
 #endif
 

include/rtc/channel.hpp

@@ -21,6 +21,7 @@
 
 #include "include.hpp"
 
+#include <atomic>
 #include <functional>
 #include <variant>
 
@@ -28,32 +29,55 @@ namespace rtc {
 
 class Channel {
 public:
-	virtual void close(void) = 0;
+	Channel() = default;
-	virtual void send(const std::variant<binary, string> &data) = 0;
+	virtual ~Channel() = default;
 
-	virtual bool isOpen(void) const = 0;
+	virtual void close() = 0;
-	virtual bool isClosed(void) const = 0;
+	virtual bool send(const std::variant<binary, string> &data) = 0; // returns false if buffered
+
+	virtual bool isOpen() const = 0;
+	virtual bool isClosed() const = 0;
+	virtual size_t maxMessageSize() const; // max message size in a call to send
+	virtual size_t bufferedAmount() const; // total size buffered to send
 
 	void onOpen(std::function<void()> callback);
 	void onClosed(std::function<void()> callback);
 	void onError(std::function<void(const string &error)> callback);
+
 	void onMessage(std::function<void(const std::variant<binary, string> &data)> callback);
 	void onMessage(std::function<void(const binary &data)> binaryCallback,
 	               std::function<void(const string &data)> stringCallback);
 
+	void onBufferedAmountLow(std::function<void()> callback);
+	void setBufferedAmountLowThreshold(size_t amount);
+
+	// Extended API
+	virtual std::optional<std::variant<binary, string>> receive() = 0; // only if onMessage unset
+	virtual size_t availableAmount() const; // total size available to receive
+	void onAvailable(std::function<void()> callback);
+
 protected:
-	virtual void triggerOpen(void);
+	virtual void triggerOpen();
-	virtual void triggerClosed(void);
+	virtual void triggerClosed();
 	virtual void triggerError(const string &error);
-	virtual void triggerMessage(const std::variant<binary, string> &data);
+	virtual void triggerAvailable(size_t count);
+	virtual void triggerBufferedAmount(size_t amount);
+
+	void resetCallbacks();
 
 private:
-	std::function<void()> mOpenCallback;
+	synchronized_callback<> mOpenCallback;
-	std::function<void()> mClosedCallback;
+	synchronized_callback<> mClosedCallback;
-	std::function<void(const string &)> mErrorCallback;
+	synchronized_callback<const string &> mErrorCallback;
-	std::function<void(const std::variant<binary, string> &)> mMessageCallback;
+	synchronized_callback<const std::variant<binary, string> &> mMessageCallback;
+	synchronized_callback<> mAvailableCallback;
+	synchronized_callback<> mBufferedAmountLowCallback;
+
+	std::atomic<size_t> mBufferedAmount = 0;
+	std::atomic<size_t> mBufferedAmountLowThreshold = 0;
 };
 
 } // namespace rtc
 
 #endif // RTC_CHANNEL_H
+

include/rtc/configuration.hpp

@@ -27,16 +27,47 @@
 namespace rtc {
 
 struct IceServer {
-	IceServer(const string &host_);
+	enum class Type { Stun, Turn };
-	IceServer(const string &hostname_, uint16_t port_);
+	enum class RelayType { TurnUdp, TurnTcp, TurnTls };
-	IceServer(const string &hostname_, const string &service_);
+
+	// Any type
+	IceServer(const string &url);
+
+	// STUN
+	IceServer(string hostname_, uint16_t port_);
+	IceServer(string hostname_, string service_);
+
+	// TURN
+	IceServer(string hostname_, uint16_t port, string username_, string password_,
+	          RelayType relayType_ = RelayType::TurnUdp);
+	IceServer(string hostname_, string service_, string username_, string password_,
+	          RelayType relayType_ = RelayType::TurnUdp);
 
 	string hostname;
 	string service;
+	Type type;
+	string username;
+	string password;
+	RelayType relayType;
+};
+
+struct ProxyServer {
+	enum class Type { None = 0, Socks5, Http, Last = Http };
+
+	ProxyServer(Type type_, string ip_, uint16_t port_, string username_ = "",
+	            string password_ = "");
+
+	Type type;
+	string ip;
+	uint16_t port;
+	string username;
+	string password;
 };
 
 struct Configuration {
 	std::vector<IceServer> iceServers;
+	std::optional<ProxyServer> proxyServer;
+	bool enableIceTcp = false;
 	uint16_t portRangeBegin = 1024;
 	uint16_t portRangeEnd = 65535;
 };

include/rtc/datachannel.hpp

@@ -22,10 +22,13 @@
 #include "channel.hpp"
 #include "include.hpp"
 #include "message.hpp"
+#include "queue.hpp"
 #include "reliability.hpp"
 
+#include <atomic>
 #include <chrono>
 #include <functional>
+#include <type_traits>
 #include <variant>
 
 namespace rtc {
@@ -33,41 +36,84 @@ namespace rtc {
 class SctpTransport;
 class PeerConnection;
 
-class DataChannel : public Channel {
+class DataChannel final : public std::enable_shared_from_this<DataChannel>, public Channel {
 public:
-	DataChannel(unsigned int stream_, string label_, string protocol_, Reliability reliability_);
+	DataChannel(std::weak_ptr<PeerConnection> pc, unsigned int stream, string label,
-	DataChannel(unsigned int stream, std::shared_ptr<SctpTransport> sctpTransport);
+	            string protocol, Reliability reliability);
+	DataChannel(std::weak_ptr<PeerConnection> pc, std::weak_ptr<SctpTransport> transport,
+	            unsigned int stream);
 	~DataChannel();
 
-	void close(void);
-	void send(const std::variant<binary, string> &data);
-	void send(const byte *data, size_t size);
-
 	unsigned int stream() const;
 	string label() const;
 	string protocol() const;
 	Reliability reliability() const;
 
-	bool isOpen(void) const;
+	void close(void) override;
-	bool isClosed(void) const;
+	bool send(const std::variant<binary, string> &data) override;
+	bool send(const byte *data, size_t size);
+	template <typename Buffer> bool sendBuffer(const Buffer &buf);
+	template <typename Iterator> bool sendBuffer(Iterator first, Iterator last);
+
+	bool isOpen(void) const override;
+	bool isClosed(void) const override;
+	size_t maxMessageSize() const override;
+
+	// Extended API
+	size_t availableAmount() const override;
+	std::optional<std::variant<binary, string>> receive() override;
 
 private:
-	void open(std::shared_ptr<SctpTransport> sctpTransport);
+	void remoteClose();
+	void open(std::shared_ptr<SctpTransport> transport);
+	bool outgoing(message_ptr message);
 	void incoming(message_ptr message);
 	void processOpenMessage(message_ptr message);
 
-	const unsigned int mStream;
+	const std::weak_ptr<PeerConnection> mPeerConnection;
-	std::shared_ptr<SctpTransport> mSctpTransport;
+	std::weak_ptr<SctpTransport> mSctpTransport;
+
+	unsigned int mStream;
 	string mLabel;
 	string mProtocol;
 	std::shared_ptr<Reliability> mReliability;
 
-	bool mIsOpen = false;
+	std::atomic<bool> mIsOpen = false;
-	bool mIsClosed = false;
+	std::atomic<bool> mIsClosed = false;
+
+	Queue<message_ptr> mRecvQueue;
 
 	friend class PeerConnection;
 };
 
+template <typename Buffer> std::pair<const byte *, size_t> to_bytes(const Buffer &buf) {
+	using T = typename std::remove_pointer<decltype(buf.data())>::type;
+	using E = typename std::conditional<std::is_void<T>::value, byte, T>::type;
+	return std::make_pair(static_cast<const byte *>(static_cast<const void *>(buf.data())),
+	                      buf.size() * sizeof(E));
+}
+
+template <typename Buffer> bool DataChannel::sendBuffer(const Buffer &buf) {
+	auto [bytes, size] = to_bytes(buf);
+	auto message = std::make_shared<Message>(size);
+	std::copy(bytes, bytes + size, message->data());
+	return outgoing(message);
+}
+
+template <typename Iterator> bool DataChannel::sendBuffer(Iterator first, Iterator last) {
+	size_t size = 0;
+	for (Iterator it = first; it != last; ++it)
+		size += it->size();
+
+	auto message = std::make_shared<Message>(size);
+	auto pos = message->begin();
+	for (Iterator it = first; it != last; ++it) {
+		auto [bytes, size] = to_bytes(*it);
+		pos = std::copy(bytes, bytes + size, pos);
+	}
+	return outgoing(message);
+}
+
 } // namespace rtc
 
 #endif

include/rtc/description.hpp

@@ -35,33 +35,62 @@ public:
 	enum class Role { ActPass = 0, Passive = 1, Active = 2 };
 
 	Description(const string &sdp, const string &typeString = "");
+	Description(const string &sdp, Type type);
 	Description(const string &sdp, Type type, Role role);
 
 	Type type() const;
 	string typeString() const;
 	Role role() const;
 	string roleString() const;
-	string mid() const;
+	string dataMid() const;
 	std::optional<string> fingerprint() const;
 	std::optional<uint16_t> sctpPort() const;
+	std::optional<size_t> maxMessageSize() const;
+	bool ended() const;
 
+	void hintType(Type type);
 	void setFingerprint(string fingerprint);
 	void setSctpPort(uint16_t port);
+	void setMaxMessageSize(size_t size);
+
 	void addCandidate(Candidate candidate);
 	void endCandidates();
+	std::vector<Candidate> extractCandidates();
+
+	bool hasMedia() const;
+	void addMedia(const Description &source);
 
 	operator string() const;
+	string generateSdp(const string &eol) const;
 
 private:
 	Type mType;
 	Role mRole;
 	string mSessionId;
-	string mMid;
 	string mIceUfrag, mIcePwd;
 	std::optional<string> mFingerprint;
-	std::optional<uint16_t> mSctpPort;
+
+	// Data
+	struct Data {
+		string mid;
+		std::optional<uint16_t> sctpPort;
+		std::optional<size_t> maxMessageSize;
+	};
+	Data mData;
+
+	// Media (non-data)
+	struct Media {
+		Media(const string &mline);
+		string type;
+		string description;
+		string mid;
+		std::vector<string> attributes;
+	};
+	std::map<string, Media> mMedia; // by mid
+
+	// Candidates
 	std::vector<Candidate> mCandidates;
-	bool mTrickle;
+	bool mEnded = false;
 
 	static Type stringToType(const string &typeString);
 	static string typeToString(Type type);

include/rtc/include.hpp

@@ -19,9 +19,28 @@
 #ifndef RTC_INCLUDE_H
 #define RTC_INCLUDE_H
 
+#ifndef RTC_ENABLE_MEDIA
+#define RTC_ENABLE_MEDIA 1
+#endif
+
+#ifndef RTC_ENABLE_WEBSOCKET
+#define RTC_ENABLE_WEBSOCKET 1
+#endif
+
+#ifdef _WIN32
+#ifndef _WIN32_WINNT
+#define _WIN32_WINNT 0x0602
+#endif
+#endif
+
+#include "log.hpp"
+
 #include <cstddef>
+#include <functional>
 #include <memory>
+#include <mutex>
 #include <optional>
+#include <string>
 #include <vector>
 
 namespace rtc {
@@ -32,6 +51,7 @@ using binary = std::vector<byte>;
 
 using std::nullopt;
 
+using std::size_t;
 using std::uint16_t;
 using std::uint32_t;
 using std::uint64_t;
@@ -41,9 +61,51 @@ const size_t MAX_NUMERICNODE_LEN = 48; // Max IPv6 string representation length
 const size_t MAX_NUMERICSERV_LEN = 6;  // Max port string representation length
 
 const uint16_t DEFAULT_SCTP_PORT = 5000; // SCTP port to use by default
+const size_t DEFAULT_MAX_MESSAGE_SIZE = 65536;    // Remote max message size if not specified in SDP
+const size_t LOCAL_MAX_MESSAGE_SIZE = 256 * 1024; // Local max message size
 
+// overloaded helper
 template <class... Ts> struct overloaded : Ts... { using Ts::operator()...; };
 template <class... Ts> overloaded(Ts...)->overloaded<Ts...>;
+
+// weak_ptr bind helper
+template <typename F, typename T, typename... Args> auto weak_bind(F &&f, T *t, Args &&... _args) {
+	return [bound = std::bind(f, t, _args...), weak_this = t->weak_from_this()](auto &&... args) {
+		using result_type = typename decltype(bound)::result_type;
+		if (auto shared_this = weak_this.lock())
+			return bound(args...);
+		else
+			return static_cast<result_type>(false);
+	};
+}
+
+template <typename... P> class synchronized_callback {
+public:
+	synchronized_callback() = default;
+	synchronized_callback(std::function<void(P...)> func) { *this = std::move(func); }
+	~synchronized_callback() { *this = nullptr; }
+
+	synchronized_callback &operator=(std::function<void(P...)> func) {
+		std::lock_guard lock(mutex);
+		callback = std::move(func);
+		return *this;
+	}
+
+	void operator()(P... args) const {
+		std::lock_guard lock(mutex);
+		if (callback)
+			callback(args...);
+	}
+
+	operator bool() const {
+		std::lock_guard lock(mutex);
+		return callback ? true : false;
+	}
+
+private:
+	std::function<void(P...)> callback;
+	mutable std::recursive_mutex mutex;
+};
 }
 
 #endif

include/rtc/init.hpp

@@ -0,0 +1,52 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_INIT_H
+#define RTC_INIT_H
+
+#include "include.hpp"
+
+#include <mutex>
+
+namespace rtc {
+
+class Init;
+using init_token = std::shared_ptr<Init>;
+
+class Init {
+public:
+	static init_token Token();
+	static void Preload();
+	static void Cleanup();
+
+	~Init();
+
+private:
+	Init();
+
+	static std::weak_ptr<Init> Weak;
+	static init_token Global;
+	static std::mutex Mutex;
+};
+
+inline void Preload() { Init::Preload(); }
+inline void Cleanup() { Init::Cleanup(); }
+
+} // namespace rtc
+
+#endif

include/rtc/log.hpp

@@ -0,0 +1,54 @@
+/**
+ * Copyright (c) 2019 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_LOG_H
+#define RTC_LOG_H
+
+// Disable warnings before including plog
+#if defined(__GNUC__) || defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wall"
+#elif defined(_MSC_VER)
+#pragma warning(push, 0)
+#endif
+
+#include "plog/Log.h"
+
+#if defined(__GNUC__) || defined(__clang__)
+#pragma GCC diagnostic pop
+#elif defined(_MSC_VER)
+#pragma warning(pop)
+#endif
+
+namespace rtc {
+
+enum class LogLevel { // Don't change, it must match plog severity
+	None = 0,
+	Fatal = 1,
+	Error = 2,
+	Warning = 3,
+	Info = 4,
+	Debug = 5,
+	Verbose = 6
+};
+
+void InitLogger(LogLevel level);
+void InitLogger(plog::Severity severity, plog::IAppender *appender = nullptr);
+}
+
+#endif

include/rtc/message.hpp

@@ -28,26 +28,44 @@
 namespace rtc {
 
 struct Message : binary {
-	enum Type { Binary, String, Control };
+	enum Type { Binary, String, Control, Reset };
+
+	Message(const Message &message) = default;
+	Message(size_t size, Type type_ = Binary) : binary(size), type(type_) {}
 
 	template <typename Iterator>
-	Message(Iterator begin_, Iterator end_, Type type_ = Binary, unsigned int stream_ = 0,
+	Message(Iterator begin_, Iterator end_, Type type_ = Binary)
-	        std::shared_ptr<Reliability> reliability_ = nullptr)
+	    : binary(begin_, end_), type(type_) {}
-	    : binary(begin_, end_), type(type_), stream(stream_), reliability(reliability_) {}
 
 	Type type;
-	unsigned int stream;
+	unsigned int stream = 0;
 	std::shared_ptr<Reliability> reliability;
 };
 
-using message_ptr = std::shared_ptr<const Message>;
+using message_ptr = std::shared_ptr<Message>;
 using message_callback = std::function<void(message_ptr message)>;
 
+constexpr auto message_size_func = [](const message_ptr &m) -> size_t {
+	return m->type == Message::Binary || m->type == Message::String ? m->size() : 0;
+};
+
 template <typename Iterator>
 message_ptr make_message(Iterator begin, Iterator end, Message::Type type = Message::Binary,
                          unsigned int stream = 0,
                          std::shared_ptr<Reliability> reliability = nullptr) {
-	return std::make_shared<Message>(begin, end, type, stream, reliability);
+	auto message = std::make_shared<Message>(begin, end, type);
+	message->stream = stream;
+	message->reliability = reliability;
+	return message;
+}
+
+inline message_ptr make_message(size_t size, Message::Type type = Message::Binary,
+                                unsigned int stream = 0,
+                                std::shared_ptr<Reliability> reliability = nullptr) {
+	auto message = std::make_shared<Message>(size, type);
+	message->stream = stream;
+	message->reliability = reliability;
+	return message;
 }
 
 } // namespace rtc

include/rtc/peerconnection.hpp

@@ -24,12 +24,18 @@
 #include "datachannel.hpp"
 #include "description.hpp"
 #include "include.hpp"
+#include "init.hpp"
 #include "message.hpp"
 #include "reliability.hpp"
 #include "rtc.hpp"
 
 #include <atomic>
 #include <functional>
+#include <future>
+#include <list>
+#include <mutex>
+#include <shared_mutex>
+#include <thread>
 #include <unordered_map>
 
 namespace rtc {
@@ -39,7 +45,10 @@ class IceTransport;
 class DtlsTransport;
 class SctpTransport;
 
-class PeerConnection {
+using certificate_ptr = std::shared_ptr<Certificate>;
+using future_certificate_ptr = std::shared_future<certificate_ptr>;
+
+class PeerConnection final : public std::enable_shared_from_this<PeerConnection> {
 public:
 	enum class State : int {
 		New = RTC_NEW,
@@ -53,19 +62,24 @@ public:
 	enum class GatheringState : int {
 		New = RTC_GATHERING_NEW,
 		InProgress = RTC_GATHERING_INPROGRESS,
-		Complete = RTC_GATHERING_COMPLETE,
+		Complete = RTC_GATHERING_COMPLETE
 	};
 
 	PeerConnection(void);
 	PeerConnection(const Configuration &config);
 	~PeerConnection();
 
+	void close();
+
 	const Configuration *config() const;
 	State state() const;
 	GatheringState gatheringState() const;
 	std::optional<Description> localDescription() const;
 	std::optional<Description> remoteDescription() const;
+	std::optional<string> localAddress() const;
+	std::optional<string> remoteAddress() const;
 
+	void setLocalDescription(std::optional<Description> description = nullopt);
 	void setRemoteDescription(Description description);
 	void addRemoteCandidate(Candidate candidate);
 
@@ -78,43 +92,77 @@ public:
 	void onStateChange(std::function<void(State state)> callback);
 	void onGatheringStateChange(std::function<void(GatheringState state)> callback);
 
-private:
+	// Stats
-	void initIceTransport(Description::Role role);
+	void clearStats();
-	void initDtlsTransport();
+	size_t bytesSent();
-	void initSctpTransport();
+	size_t bytesReceived();
+	std::optional<std::chrono::milliseconds> rtt();
 
+	// Media
+	bool hasMedia() const;
+	void sendMedia(const binary &packet);
+	void send(const byte *packet, size_t size);
+
+	void onMedia(std::function<void(const binary &packet)> callback);
+
+	// libnice only
+	bool getSelectedCandidatePair(CandidateInfo *local, CandidateInfo *remote);
+
+private:
+	std::shared_ptr<IceTransport> initIceTransport(Description::Role role);
+	std::shared_ptr<DtlsTransport> initDtlsTransport();
+	std::shared_ptr<SctpTransport> initSctpTransport();
+	void closeTransports();
+
+	void endLocalCandidates();
 	bool checkFingerprint(const std::string &fingerprint) const;
 	void forwardMessage(message_ptr message);
+	void forwardMedia(message_ptr message);
+	void forwardBufferedAmount(uint16_t stream, size_t amount);
+
+	std::shared_ptr<DataChannel> emplaceDataChannel(Description::Role role, const string &label,
+	                                                const string &protocol,
+	                                                const Reliability &reliability);
+	std::shared_ptr<DataChannel> findDataChannel(uint16_t stream);
 	void iterateDataChannels(std::function<void(std::shared_ptr<DataChannel> channel)> func);
 	void openDataChannels();
 	void closeDataChannels();
+	void remoteCloseDataChannels();
 
 	void processLocalDescription(Description description);
 	void processLocalCandidate(Candidate candidate);
-	void triggerDataChannel(std::shared_ptr<DataChannel> dataChannel);
+	void triggerDataChannel(std::weak_ptr<DataChannel> weakDataChannel);
-	void changeState(State state);
+	bool changeState(State state);
-	void changeGatheringState(GatheringState state);
+	bool changeGatheringState(GatheringState state);
+
+	void resetCallbacks();
+
+	void outgoingMedia(message_ptr message);
 
 	const Configuration mConfig;
-	const std::shared_ptr<Certificate> mCertificate;
+	const future_certificate_ptr mCertificate;
 
-	std::optional<Description> mLocalDescription;
+	init_token mInitToken = Init::Token();
-	std::optional<Description> mRemoteDescription;
+
+	std::optional<Description> mLocalDescription, mRemoteDescription;
+	mutable std::mutex mLocalDescriptionMutex, mRemoteDescriptionMutex;
 
 	std::shared_ptr<IceTransport> mIceTransport;
 	std::shared_ptr<DtlsTransport> mDtlsTransport;
 	std::shared_ptr<SctpTransport> mSctpTransport;
 
 	std::unordered_map<unsigned int, std::weak_ptr<DataChannel>> mDataChannels;
+	std::shared_mutex mDataChannelsMutex;
 
 	std::atomic<State> mState;
 	std::atomic<GatheringState> mGatheringState;
 
-	std::function<void(std::shared_ptr<DataChannel> dataChannel)> mDataChannelCallback;
+	synchronized_callback<std::shared_ptr<DataChannel>> mDataChannelCallback;
-	std::function<void(const Description &description)> mLocalDescriptionCallback;
+	synchronized_callback<const Description &> mLocalDescriptionCallback;
-	std::function<void(const Candidate &candidate)> mLocalCandidateCallback;
+	synchronized_callback<const Candidate &> mLocalCandidateCallback;
-	std::function<void(State state)> mStateChangeCallback;
+	synchronized_callback<State> mStateChangeCallback;
-	std::function<void(GatheringState state)> mGatheringStateChangeCallback;
+	synchronized_callback<GatheringState> mGatheringStateChangeCallback;
+	synchronized_callback<const binary &> mMediaCallback;
 };
 
 } // namespace rtc

include/rtc/queue.hpp

@@ -0,0 +1,148 @@
+/**
+ * Copyright (c) 2019 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_QUEUE_H
+#define RTC_QUEUE_H
+
+#include "include.hpp"
+
+#include <atomic>
+#include <chrono>
+#include <condition_variable>
+#include <mutex>
+#include <optional>
+#include <queue>
+
+namespace rtc {
+
+template <typename T> class Queue {
+public:
+	using amount_function = std::function<size_t(const T &element)>;
+
+	Queue(size_t limit = 0, amount_function func = nullptr);
+	~Queue();
+
+	void stop();
+	bool empty() const;
+	size_t size() const;   // elements
+	size_t amount() const; // amount
+	void push(T element);
+	std::optional<T> pop();
+	std::optional<T> peek();
+	std::optional<T> exchange(T element);
+	bool wait(const std::optional<std::chrono::milliseconds> &duration = nullopt);
+
+private:
+	const size_t mLimit;
+	size_t mAmount;
+	std::queue<T> mQueue;
+	std::condition_variable mPopCondition, mPushCondition;
+	amount_function mAmountFunction;
+	bool mStopping = false;
+
+	mutable std::mutex mMutex;
+};
+
+template <typename T>
+Queue<T>::Queue(size_t limit, amount_function func) : mLimit(limit), mAmount(0) {
+	mAmountFunction = func ? func : [](const T &element) -> size_t {
+		static_cast<void>(element);
+		return 1;
+	};
+}
+
+template <typename T> Queue<T>::~Queue() { stop(); }
+
+template <typename T> void Queue<T>::stop() {
+	std::lock_guard lock(mMutex);
+	mStopping = true;
+	mPopCondition.notify_all();
+	mPushCondition.notify_all();
+}
+
+template <typename T> bool Queue<T>::empty() const {
+	std::lock_guard lock(mMutex);
+	return mQueue.empty();
+}
+
+template <typename T> size_t Queue<T>::size() const {
+	std::lock_guard lock(mMutex);
+	return mQueue.size();
+}
+
+template <typename T> size_t Queue<T>::amount() const {
+	std::lock_guard lock(mMutex);
+	return mAmount;
+}
+
+template <typename T> void Queue<T>::push(T element) {
+	std::unique_lock lock(mMutex);
+	mPushCondition.wait(lock, [this]() { return !mLimit || mQueue.size() < mLimit || mStopping; });
+	if (!mStopping) {
+		mAmount += mAmountFunction(element);
+		mQueue.emplace(std::move(element));
+		mPopCondition.notify_one();
+	}
+}
+
+template <typename T> std::optional<T> Queue<T>::pop() {
+	std::unique_lock lock(mMutex);
+	mPopCondition.wait(lock, [this]() { return !mQueue.empty() || mStopping; });
+	if (!mQueue.empty()) {
+		mAmount -= mAmountFunction(mQueue.front());
+		std::optional<T> element{std::move(mQueue.front())};
+		mQueue.pop();
+		return element;
+	} else {
+		return nullopt;
+	}
+}
+
+template <typename T> std::optional<T> Queue<T>::peek() {
+	std::unique_lock lock(mMutex);
+	if (!mQueue.empty()) {
+		return std::optional<T>{mQueue.front()};
+	} else {
+		return nullopt;
+	}
+}
+
+template <typename T> std::optional<T> Queue<T>::exchange(T element) {
+	std::unique_lock lock(mMutex);
+	if (!mQueue.empty()) {
+		std::swap(mQueue.front(), element);
+		return std::optional<T>{element};
+	} else {
+		return nullopt;
+	}
+}
+
+template <typename T>
+bool Queue<T>::wait(const std::optional<std::chrono::milliseconds> &duration) {
+	std::unique_lock lock(mMutex);
+	if (duration)
+		mPopCondition.wait_for(lock, *duration, [this]() { return !mQueue.empty() || mStopping; });
+	else
+		mPopCondition.wait(lock, [this]() { return !mQueue.empty() || mStopping; });
+	return !mStopping;
+}
+
+} // namespace rtc
+
+#endif
+

include/rtc/rtc.h

@@ -23,7 +23,17 @@
 extern "C" {
 #endif
 
-// libdatachannel rtc C API
+#include <stdint.h>
+
+// libdatachannel C API
+
+#ifndef RTC_ENABLE_MEDIA
+#define RTC_ENABLE_MEDIA 1
+#endif
+
+#ifndef RTC_ENABLE_WEBSOCKET
+#define RTC_ENABLE_WEBSOCKET 1
+#endif
 
 typedef enum {
 	RTC_NEW = 0,
@@ -32,39 +42,103 @@ typedef enum {
 	RTC_DISCONNECTED = 3,
 	RTC_FAILED = 4,
 	RTC_CLOSED = 5
-} rtc_state_t;
+} rtcState;
 
 typedef enum {
 	RTC_GATHERING_NEW = 0,
 	RTC_GATHERING_INPROGRESS = 1,
 	RTC_GATHERING_COMPLETE = 2
-} rtc_gathering_state_t;
+} rtcGatheringState;
 
-int rtcCreatePeerConnection(const char **iceServers, int iceServersCount);
+typedef enum { // Don't change, it must match plog severity
-void rtcDeletePeerConnection(int pc);
+	RTC_LOG_NONE = 0,
-int rtcCreateDataChannel(int pc, const char *label);
+	RTC_LOG_FATAL = 1,
-void rtcDeleteDataChannel(int dc);
+	RTC_LOG_ERROR = 2,
-void rtcSetDataChannelCallback(int pc, void (*dataChannelCallback)(int, void *));
+	RTC_LOG_WARNING = 3,
-void rtcSetLocalDescriptionCallback(int pc, void (*descriptionCallback)(const char *, const char *,
+	RTC_LOG_INFO = 4,
-                                                                        void *));
+	RTC_LOG_DEBUG = 5,
-void rtcSetLocalCandidateCallback(int pc,
+	RTC_LOG_VERBOSE = 6
-                                  void (*candidateCallback)(const char *, const char *, void *));
+} rtcLogLevel;
-void rtcSetStateChangeCallback(int pc, void (*stateCallback)(rtc_state_t state, void *));
+
-void rtcSetGatheringStateChangeCallback(int pc,
+#define RTC_ERR_SUCCESS 0
-                                         void (*gatheringStateCallback)(rtc_gathering_state_t state,
+#define RTC_ERR_INVALID -1 // invalid argument
-                                                                        void *));
+#define RTC_ERR_FAILURE -2 // runtime error
-void rtcSetRemoteDescription(int pc, const char *sdp, const char *type);
+
-void rtcAddRemoteCandidate(int pc, const char *candidate, const char *mid);
+typedef struct {
-int rtcGetDataChannelLabel(int dc, char *data, int size);
+	const char **iceServers;
-void rtcSetOpenCallback(int dc, void (*openCallback)(void *));
+	int iceServersCount;
-void rtcSetErrorCallback(int dc, void (*errorCallback)(const char *, void *));
+	uint16_t portRangeBegin;
-void rtcSetMessageCallback(int dc, void (*messageCallback)(const char *, int, void *));
+	uint16_t portRangeEnd;
-int rtcSendMessage(int dc, const char *data, int size);
+} rtcConfiguration;
-void rtcSetUserPointer(int i, void *ptr);
+
+typedef void (*dataChannelCallbackFunc)(int dc, void *ptr);
+typedef void (*descriptionCallbackFunc)(const char *sdp, const char *type, void *ptr);
+typedef void (*candidateCallbackFunc)(const char *cand, const char *mid, void *ptr);
+typedef void (*stateChangeCallbackFunc)(rtcState state, void *ptr);
+typedef void (*gatheringStateCallbackFunc)(rtcGatheringState state, void *ptr);
+typedef void (*openCallbackFunc)(void *ptr);
+typedef void (*closedCallbackFunc)(void *ptr);
+typedef void (*errorCallbackFunc)(const char *error, void *ptr);
+typedef void (*messageCallbackFunc)(const char *message, int size, void *ptr);
+typedef void (*bufferedAmountLowCallbackFunc)(void *ptr);
+typedef void (*availableCallbackFunc)(void *ptr);
+
+// Log
+void rtcInitLogger(rtcLogLevel level);
+
+// User pointer
+void rtcSetUserPointer(int id, void *ptr);
+
+// PeerConnection
+int rtcCreatePeerConnection(const rtcConfiguration *config); // returns pc id
+int rtcDeletePeerConnection(int pc);
+
+int rtcSetDataChannelCallback(int pc, dataChannelCallbackFunc cb);
+int rtcSetLocalDescriptionCallback(int pc, descriptionCallbackFunc cb);
+int rtcSetLocalCandidateCallback(int pc, candidateCallbackFunc cb);
+int rtcSetStateChangeCallback(int pc, stateChangeCallbackFunc cb);
+int rtcSetGatheringStateChangeCallback(int pc, gatheringStateCallbackFunc cb);
+
+int rtcSetRemoteDescription(int pc, const char *sdp, const char *type);
+int rtcAddRemoteCandidate(int pc, const char *cand, const char *mid);
+
+int rtcGetLocalAddress(int pc, char *buffer, int size);
+int rtcGetRemoteAddress(int pc, char *buffer, int size);
+
+// DataChannel
+int rtcCreateDataChannel(int pc, const char *label); // returns dc id
+int rtcDeleteDataChannel(int dc);
+
+int rtcGetDataChannelLabel(int dc, char *buffer, int size);
+
+// WebSocket
+#if RTC_ENABLE_WEBSOCKET
+int rtcCreateWebSocket(const char *url); // returns ws id
+int rtcDeleteWebsocket(int ws);
+#endif
+
+// DataChannel and WebSocket common API
+int rtcSetOpenCallback(int id, openCallbackFunc cb);
+int rtcSetClosedCallback(int id, closedCallbackFunc cb);
+int rtcSetErrorCallback(int id, errorCallbackFunc cb);
+int rtcSetMessageCallback(int id, messageCallbackFunc cb);
+int rtcSendMessage(int id, const char *data, int size);
+
+int rtcGetBufferedAmount(int id); // total size buffered to send
+int rtcSetBufferedAmountLowThreshold(int id, int amount);
+int rtcSetBufferedAmountLowCallback(int id, bufferedAmountLowCallbackFunc cb);
+
+// DataChannel and WebSocket common extended API
+int rtcGetAvailableAmount(int id); // total size available to receive
+int rtcSetAvailableCallback(int id, availableCallbackFunc cb);
+int rtcReceiveMessage(int id, char *buffer, int *size);
+
+// Optional preload and cleanup
+void rtcPreload();
+void rtcCleanup();
 
 #ifdef __cplusplus
 } // extern "C"
 #endif
 
 #endif
-

include/rtc/rtc.hpp

@@ -17,8 +17,13 @@
  */
 
 // C++ API
+#include "include.hpp"
+#include "init.hpp" // for rtc::Cleanup()
+#include "log.hpp"
+//
 #include "datachannel.hpp"
 #include "peerconnection.hpp"
+#include "websocket.hpp"
 
 // C API
 #include "rtc.h"

include/rtc/websocket.hpp

@@ -0,0 +1,94 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_WEBSOCKET_H
+#define RTC_WEBSOCKET_H
+
+#if RTC_ENABLE_WEBSOCKET
+
+#include "channel.hpp"
+#include "include.hpp"
+#include "init.hpp"
+#include "message.hpp"
+#include "queue.hpp"
+
+#include <atomic>
+#include <optional>
+#include <thread>
+#include <variant>
+
+namespace rtc {
+
+class TcpTransport;
+class TlsTransport;
+class WsTransport;
+
+class WebSocket final : public Channel, public std::enable_shared_from_this<WebSocket> {
+public:
+	enum class State : int {
+		Connecting = 0,
+		Open = 1,
+		Closing = 2,
+		Closed = 3,
+	};
+
+	WebSocket();
+	~WebSocket();
+
+	State readyState() const;
+
+	void open(const string &url);
+	void close() override;
+	bool send(const std::variant<binary, string> &data) override;
+
+	bool isOpen() const override;
+	bool isClosed() const override;
+	size_t maxMessageSize() const override;
+
+	// Extended API
+	std::optional<std::variant<binary, string>> receive() override;
+	size_t availableAmount() const override; // total size available to receive
+
+private:
+	bool changeState(State state);
+	void remoteClose();
+	bool outgoing(message_ptr message);
+	void incoming(message_ptr message);
+
+	std::shared_ptr<TcpTransport> initTcpTransport();
+	std::shared_ptr<TlsTransport> initTlsTransport();
+	std::shared_ptr<WsTransport> initWsTransport();
+	void closeTransports();
+
+	init_token mInitToken = Init::Token();
+
+	std::shared_ptr<TcpTransport> mTcpTransport;
+	std::shared_ptr<TlsTransport> mTlsTransport;
+	std::shared_ptr<WsTransport> mWsTransport;
+	std::recursive_mutex mInitMutex;
+
+	string mScheme, mHost, mHostname, mService, mPath;
+	std::atomic<State> mState = State::Closed;
+
+	Queue<message_ptr> mRecvQueue;
+};
+} // namespace rtc
+
+#endif
+
+#endif // RTC_WEBSOCKET_H

src/base64.cpp

@@ -0,0 +1,65 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#if RTC_ENABLE_WEBSOCKET
+
+#include "base64.hpp"
+
+namespace rtc {
+
+using std::to_integer;
+
+string to_base64(const binary &data) {
+	static const char tab[] =
+	    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+	string out;
+	out.reserve(3 * ((data.size() + 3) / 4));
+	int i = 0;
+	while (data.size() - i >= 3) {
+		auto d0 = to_integer<uint8_t>(data[i]);
+		auto d1 = to_integer<uint8_t>(data[i + 1]);
+		auto d2 = to_integer<uint8_t>(data[i + 2]);
+		out += tab[d0 >> 2];
+		out += tab[((d0 & 3) << 4) | (d1 >> 4)];
+		out += tab[((d1 & 0x0F) << 2) | (d2 >> 6)];
+		out += tab[d2 & 0x3F];
+		i += 3;
+	}
+
+	int left = data.size() - i;
+	if (left) {
+		auto d0 = to_integer<uint8_t>(data[i]);
+		out += tab[d0 >> 2];
+		if (left == 1) {
+			out += tab[(d0 & 3) << 4];
+			out += '=';
+		} else { // left == 2
+			auto d1 = to_integer<uint8_t>(data[i + 1]);
+			out += tab[((d0 & 3) << 4) | (d1 >> 4)];
+			out += tab[(d1 & 0x0F) << 2];
+		}
+		out += '=';
+	}
+
+	return out;
+}
+
+} // namespace rtc
+
+#endif

src/base64.hpp

@@ -0,0 +1,34 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_BASE64_H
+#define RTC_BASE64_H
+
+#if RTC_ENABLE_WEBSOCKET
+
+#include "include.hpp"
+
+namespace rtc {
+
+string to_base64(const binary &data);
+
+}
+
+#endif
+
+#endif

src/candidate.cpp

@@ -22,8 +22,14 @@
 #include <array>
 #include <sstream>
 
+#ifdef _WIN32
+#include <winsock2.h>
+#include <ws2tcpip.h>
+#else
 #include <netdb.h>
 #include <sys/socket.h>
+#endif
+
 #include <sys/types.h>
 
 using std::array;
@@ -40,7 +46,7 @@ inline bool hasprefix(const string &str, const string &prefix) {
 
 namespace rtc {
 
-Candidate::Candidate(string candidate, string mid) {
+Candidate::Candidate(string candidate, string mid) : mIsResolved(false) {
 	const std::array prefixes{"a=", "candidate:"};
 	for (string prefix : prefixes)
 		if (hasprefix(candidate, prefix))
@@ -48,13 +54,25 @@ Candidate::Candidate(string candidate, string mid) {
 
 	mCandidate = std::move(candidate);
 	mMid = std::move(mid);
+}
 
-	// See RFC 5245 for format
+bool Candidate::resolve(ResolveMode mode) {
-	std::stringstream ss(mCandidate);
+	if (mIsResolved)
+		return true;
+
+	PLOG_VERBOSE << "Resolving candidate (mode="
+				 << (mode == ResolveMode::Simple ? "simple" : "lookup")
+				 << "): " << mCandidate;
+
+	// See RFC 8445 for format
+	std::istringstream iss(mCandidate);
 	int component{0}, priority{0};
 	string foundation, transport, node, service, typ_, type;
-	if (ss >> foundation >> component >> transport >> priority &&
+	if (iss >> foundation >> component >> transport >> priority &&
-	    ss >> node >> service >> typ_ >> type && typ_ == "typ") {
+	    iss >> node >> service >> typ_ >> type && typ_ == "typ") {
+
+		string left;
+		std::getline(iss, left);
 
 		// Try to resolve the node
 		struct addrinfo hints = {};
@@ -64,6 +82,15 @@ Candidate::Candidate(string candidate, string mid) {
 			hints.ai_socktype = SOCK_DGRAM;
 			hints.ai_protocol = IPPROTO_UDP;
 		}
+
+		if (transport == "TCP" || transport == "tcp") {
+			hints.ai_socktype = SOCK_STREAM;
+			hints.ai_protocol = IPPROTO_TCP;
+		}
+
+		if (mode == ResolveMode::Simple)
+			hints.ai_flags |= AI_NUMERICHOST;
+
 		struct addrinfo *result = nullptr;
 		if (getaddrinfo(node.c_str(), service.c_str(), &hints, &result) == 0) {
 			for (auto p = result; p; p = p->ai_next)
@@ -74,24 +101,26 @@ Candidate::Candidate(string candidate, string mid) {
 					if (getnameinfo(p->ai_addr, p->ai_addrlen, nodebuffer, MAX_NUMERICNODE_LEN,
 					                servbuffer, MAX_NUMERICSERV_LEN,
 					                NI_NUMERICHOST | NI_NUMERICSERV) == 0) {
-						string left;
-						std::getline(ss, left);
 						const char sp{' '};
-						ss.clear();
+						std::ostringstream oss;
-						ss << foundation << sp << component << sp << transport << sp << priority;
+						oss << foundation << sp << component << sp << transport << sp << priority;
-						ss << sp << nodebuffer << sp << servbuffer << sp << "typ" << sp << type;
+						oss << sp << nodebuffer << sp << servbuffer << sp << "typ" << sp << type;
-						if (!left.empty())
+						oss << left;
-							ss << left;
+						mCandidate = oss.str();
-						mCandidate = ss.str();
+						PLOG_VERBOSE << "Resolved candidate: " << mCandidate;
-						break;
+						return mIsResolved = true;
 					}
 				}
 		}
 
 		freeaddrinfo(result);
 	}
+
+	return false;
 }
 
+bool Candidate::isResolved() const { return mIsResolved; }
+
 string Candidate::candidate() const { return "candidate:" + mCandidate; }
 
 string Candidate::mid() const { return mMid; }
@@ -108,3 +137,32 @@ std::ostream &operator<<(std::ostream &out, const rtc::Candidate &candidate) {
 	return out << std::string(candidate);
 }
 
+std::ostream &operator<<(std::ostream &out, const rtc::CandidateType &type) {
+	switch (type) {
+	case rtc::CandidateType::Host:
+		return out << "Host";
+	case rtc::CandidateType::PeerReflexive:
+		return out << "PeerReflexive";
+	case rtc::CandidateType::Relayed:
+		return out << "Relayed";
+	case rtc::CandidateType::ServerReflexive:
+		return out << "ServerReflexive";
+	default:
+		return out << "Unknown";
+	}
+}
+
+std::ostream &operator<<(std::ostream &out, const rtc::CandidateTransportType &transportType) {
+	switch (transportType) {
+	case rtc::CandidateTransportType::TcpActive:
+		return out << "TcpActive";
+	case rtc::CandidateTransportType::TcpPassive:
+		return out << "TcpPassive";
+	case rtc::CandidateTransportType::TcpSo:
+		return out << "TcpSo";
+	case rtc::CandidateTransportType::Udp:
+		return out << "Udp";
+	default:
+		return out << "Unknown";
+	}
+}

src/certificate.cpp

@@ -25,107 +25,60 @@
 #include <sstream>
 #include <unordered_map>
 
-#include <gnutls/crypto.h>
-
 using std::shared_ptr;
 using std::string;
+using std::unique_ptr;
 
-namespace {
+#if USE_GNUTLS
-
-void check_gnutls(int ret, const string &message = "GnuTLS error") {
-	if (ret != GNUTLS_E_SUCCESS)
-		throw std::runtime_error(message + ": " + gnutls_strerror(ret));
-}
-
-gnutls_certificate_credentials_t *create_credentials() {
-	auto creds = new gnutls_certificate_credentials_t;
-	check_gnutls(gnutls_certificate_allocate_credentials(creds));
-	return creds;
-}
-
-void delete_credentials(gnutls_certificate_credentials_t *creds) {
-	gnutls_certificate_free_credentials(*creds);
-	delete creds;
-}
-
-gnutls_x509_crt_t *create_crt() {
-	auto crt = new gnutls_x509_crt_t;
-	check_gnutls(gnutls_x509_crt_init(crt));
-	return crt;
-}
-
-void delete_crt(gnutls_x509_crt_t *crt) {
-	gnutls_x509_crt_deinit(*crt);
-	delete crt;
-}
-
-gnutls_x509_privkey_t *create_privkey() {
-	auto privkey = new gnutls_x509_privkey_t;
-	check_gnutls(gnutls_x509_privkey_init(privkey));
-	return privkey;
-}
-
-void delete_privkey(gnutls_x509_privkey_t *privkey) {
-	gnutls_x509_privkey_deinit(*privkey);
-	delete privkey;
-}
-
-gnutls_datum_t make_datum(char *data, size_t size) {
-	gnutls_datum_t datum;
-	datum.data = reinterpret_cast<unsigned char *>(data);
-	datum.size = size;
-	return datum;
-}
-
-} // namespace
 
 namespace rtc {
 
 Certificate::Certificate(string crt_pem, string key_pem)
-    : mCredentials(create_credentials(), delete_credentials) {
+    : mCredentials(gnutls::new_credentials(), gnutls::free_credentials) {
 
-	gnutls_datum_t crt_datum = make_datum(crt_pem.data(), crt_pem.size());
+	gnutls_datum_t crt_datum = gnutls::make_datum(crt_pem.data(), crt_pem.size());
-	gnutls_datum_t key_datum = make_datum(key_pem.data(), key_pem.size());
+	gnutls_datum_t key_datum = gnutls::make_datum(key_pem.data(), key_pem.size());
 
-	check_gnutls(gnutls_certificate_set_x509_key_mem(*mCredentials, &crt_datum, &key_datum,
+	gnutls::check(gnutls_certificate_set_x509_key_mem(*mCredentials, &crt_datum, &key_datum,
 	                                                  GNUTLS_X509_FMT_PEM),
 	              "Unable to import PEM");
 
-	auto create_crt_list = [this]() -> gnutls_x509_crt_t * {
+	auto new_crt_list = [this]() -> gnutls_x509_crt_t * {
 		gnutls_x509_crt_t *crt_list = nullptr;
 		unsigned int crt_list_size = 0;
-		check_gnutls(gnutls_certificate_get_x509_crt(*mCredentials, 0, &crt_list, &crt_list_size));
+		gnutls::check(gnutls_certificate_get_x509_crt(*mCredentials, 0, &crt_list, &crt_list_size));
 		assert(crt_list_size == 1);
 		return crt_list;
 	};
 
-	auto delete_crt_list = [](gnutls_x509_crt_t *crt_list) {
+	auto free_crt_list = [](gnutls_x509_crt_t *crt_list) {
 		gnutls_x509_crt_deinit(crt_list[0]);
 		gnutls_free(crt_list);
 	};
 
-	std::unique_ptr<gnutls_x509_crt_t, decltype(delete_crt_list)> crt_list(create_crt_list(),
+	std::unique_ptr<gnutls_x509_crt_t, decltype(free_crt_list)> crt_list(new_crt_list(),
-	                                                                       delete_crt_list);
+	                                                                     free_crt_list);
 
 	mFingerprint = make_fingerprint(*crt_list);
 }
 
 Certificate::Certificate(gnutls_x509_crt_t crt, gnutls_x509_privkey_t privkey)
-    : mCredentials(create_credentials(), delete_credentials), mFingerprint(make_fingerprint(crt)) {
+    : mCredentials(gnutls::new_credentials(), gnutls::free_credentials),
+      mFingerprint(make_fingerprint(crt)) {
 
-	check_gnutls(gnutls_certificate_set_x509_key(*mCredentials, &crt, 1, privkey),
+	gnutls::check(gnutls_certificate_set_x509_key(*mCredentials, &crt, 1, privkey),
 	              "Unable to set certificate and key pair in credentials");
 }
 
-string Certificate::fingerprint() const { return mFingerprint; }
-
 gnutls_certificate_credentials_t Certificate::credentials() const { return *mCredentials; }
 
+string Certificate::fingerprint() const { return mFingerprint; }
+
 string make_fingerprint(gnutls_x509_crt_t crt) {
 	const size_t size = 32;
 	unsigned char buffer[size];
 	size_t len = size;
-	check_gnutls(gnutls_x509_crt_get_fingerprint(crt, GNUTLS_DIG_SHA256, buffer, &len),
+	gnutls::check(gnutls_x509_crt_get_fingerprint(crt, GNUTLS_DIG_SHA256, buffer, &len),
 	              "X509 fingerprint error");
 
 	std::ostringstream oss;
@@ -138,20 +91,15 @@ string make_fingerprint(gnutls_x509_crt_t crt) {
 	return oss.str();
 }
 
-shared_ptr<Certificate> make_certificate(const string &commonName) {
+namespace {
-	static std::unordered_map<string, shared_ptr<Certificate>> cache;
-	static std::mutex cacheMutex;
 
-	std::lock_guard<std::mutex> lock(cacheMutex);
+certificate_ptr make_certificate_impl(string commonName) {
-	if (auto it = cache.find(commonName); it != cache.end())
+	using namespace gnutls;
-		return it->second;
+	unique_ptr<gnutls_x509_crt_t, decltype(&free_crt)> crt(new_crt(), free_crt);
-
+	unique_ptr<gnutls_x509_privkey_t, decltype(&free_privkey)> privkey(new_privkey(), free_privkey);
-	std::unique_ptr<gnutls_x509_crt_t, decltype(&delete_crt)> crt(create_crt(), delete_crt);
-	std::unique_ptr<gnutls_x509_privkey_t, decltype(&delete_privkey)> privkey(create_privkey(),
-	                                                                          delete_privkey);
 
 	const unsigned int bits = gnutls_sec_param_to_pk_bits(GNUTLS_PK_RSA, GNUTLS_SEC_PARAM_HIGH);
-	check_gnutls(gnutls_x509_privkey_generate(*privkey, GNUTLS_PK_RSA, bits, 0),
+	gnutls::check(gnutls_x509_privkey_generate(*privkey, GNUTLS_PK_RSA, bits, 0),
 	              "Unable to generate key pair");
 
 	using namespace std::chrono;
@@ -168,12 +116,153 @@ shared_ptr<Certificate> make_certificate(const string &commonName) {
 	gnutls_rnd(GNUTLS_RND_NONCE, serial, serialSize);
 	gnutls_x509_crt_set_serial(*crt, serial, serialSize);
 
-	check_gnutls(gnutls_x509_crt_sign2(*crt, *crt, *privkey, GNUTLS_DIG_SHA256, 0),
+	gnutls::check(gnutls_x509_crt_sign2(*crt, *crt, *privkey, GNUTLS_DIG_SHA256, 0),
 	              "Unable to auto-sign certificate");
 
-	auto certificate = std::make_shared<Certificate>(*crt, *privkey);
+	return std::make_shared<Certificate>(*crt, *privkey);
-	cache.emplace(std::make_pair(commonName, certificate));
+}
-	return certificate;
+
+} // namespace
+
+} // namespace rtc
+
+#else // USE_GNUTLS==0
+
+namespace rtc {
+
+Certificate::Certificate(string crt_pem, string key_pem) {
+	BIO *bio = BIO_new(BIO_s_mem());
+	BIO_write(bio, crt_pem.data(), crt_pem.size());
+	mX509 = shared_ptr<X509>(PEM_read_bio_X509(bio, nullptr, 0, 0), X509_free);
+	BIO_free(bio);
+	if (!mX509)
+		throw std::invalid_argument("Unable to import certificate PEM");
+
+	bio = BIO_new(BIO_s_mem());
+	BIO_write(bio, key_pem.data(), key_pem.size());
+	mPKey = shared_ptr<EVP_PKEY>(PEM_read_bio_PrivateKey(bio, nullptr, 0, 0), EVP_PKEY_free);
+	BIO_free(bio);
+	if (!mPKey)
+		throw std::invalid_argument("Unable to import PEM key PEM");
+
+	mFingerprint = make_fingerprint(mX509.get());
+}
+
+Certificate::Certificate(shared_ptr<X509> x509, shared_ptr<EVP_PKEY> pkey) :
+	mX509(std::move(x509)), mPKey(std::move(pkey))
+{
+	mFingerprint = make_fingerprint(mX509.get());
+}
+
+string Certificate::fingerprint() const { return mFingerprint; }
+
+std::tuple<X509 *, EVP_PKEY *> Certificate::credentials() const { return {mX509.get(), mPKey.get()}; }
+
+string make_fingerprint(X509 *x509) {
+	const size_t size = 32;
+    unsigned char buffer[size];
+    unsigned int len = size;
+    if (!X509_digest(x509, EVP_sha256(), buffer, &len))
+      throw std::runtime_error("X509 fingerprint error");
+
+	std::ostringstream oss;
+	oss << std::hex << std::uppercase << std::setfill('0');
+	for (size_t i = 0; i < len; ++i) {
+		if (i)
+			oss << std::setw(1) << ':';
+		oss << std::setw(2) << unsigned(buffer[i]);
+	}
+	return oss.str();
+}
+
+namespace {
+
+certificate_ptr make_certificate_impl(string commonName) {
+	shared_ptr<X509> x509(X509_new(), X509_free);
+	shared_ptr<EVP_PKEY> pkey(EVP_PKEY_new(), EVP_PKEY_free);
+
+    unique_ptr<RSA, decltype(&RSA_free)> rsa(RSA_new(), RSA_free);
+	unique_ptr<BIGNUM, decltype(&BN_free)> exponent(BN_new(), BN_free);
+	unique_ptr<BIGNUM, decltype(&BN_free)> serial_number(BN_new(), BN_free);
+    unique_ptr<X509_NAME, decltype(&X509_NAME_free)> name(X509_NAME_new(), X509_NAME_free);
+
+	if (!x509 || !pkey || !rsa || !exponent || !serial_number || !name)
+		throw std::runtime_error("Unable allocate structures for certificate generation");
+
+	const int bits = 4096;
+	const unsigned int e = 65537; // 2^16 + 1
+
+	if (!pkey || !rsa || !exponent || !BN_set_word(exponent.get(), e) ||
+	    !RSA_generate_key_ex(rsa.get(), bits, exponent.get(), NULL) ||
+	    !EVP_PKEY_assign_RSA(pkey.get(), rsa.release())) // the key will be freed when pkey is freed
+		throw std::runtime_error("Unable to generate key pair");
+
+	const size_t serialSize = 16;
+	auto *commonNameBytes =
+	    reinterpret_cast<unsigned char *>(const_cast<char *>(commonName.c_str()));
+
+	if (!X509_gmtime_adj(X509_get_notBefore(x509.get()), 3600 * -1) ||
+	    !X509_gmtime_adj(X509_get_notAfter(x509.get()), 3600 * 24 * 365) ||
+	    !X509_set_version(x509.get(), 1) || !X509_set_pubkey(x509.get(), pkey.get()) ||
+	    !BN_pseudo_rand(serial_number.get(), serialSize, 0, 0) ||
+	    !BN_to_ASN1_INTEGER(serial_number.get(), X509_get_serialNumber(x509.get())) ||
+	    !X509_NAME_add_entry_by_NID(name.get(), NID_commonName, MBSTRING_UTF8, commonNameBytes, -1,
+	                                -1, 0) ||
+	    !X509_set_subject_name(x509.get(), name.get()) ||
+	    !X509_set_issuer_name(x509.get(), name.get()))
+		throw std::runtime_error("Unable to set certificate properties");
+
+	if (!X509_sign(x509.get(), pkey.get(), EVP_sha256()))
+		throw std::runtime_error("Unable to auto-sign certificate");
+
+	return std::make_shared<Certificate>(x509, pkey);
+}
+
+} // namespace
+
+} // namespace rtc
+
+#endif
+
+// Common for GnuTLS and OpenSSL
+
+namespace rtc {
+
+namespace {
+
+// Helper function roughly equivalent to std::async with policy std::launch::async
+// since std::async might be unreliable on some platforms (e.g. Mingw32 on Windows)
+template <class F, class... Args>
+std::future<std::result_of_t<std::decay_t<F>(std::decay_t<Args>...)>> thread_call(F &&f,
+                                                                                  Args &&... args) {
+	using R = std::invoke_result_t<std::decay_t<F>, std::decay_t<Args>...>;
+	std::packaged_task<R()> task(std::bind(f, std::forward<Args>(args)...));
+	std::future<R> future = task.get_future();
+	std::thread t(std::move(task));
+	t.detach();
+	return future;
+}
+
+static std::unordered_map<string, future_certificate_ptr> CertificateCache;
+static std::mutex CertificateCacheMutex;
+
+} // namespace
+
+future_certificate_ptr make_certificate(string commonName) {
+	std::lock_guard lock(CertificateCacheMutex);
+
+	if (auto it = CertificateCache.find(commonName); it != CertificateCache.end())
+		return it->second;
+
+	auto future = thread_call(make_certificate_impl, commonName);
+	auto shared = future.share();
+	CertificateCache.emplace(std::move(commonName), shared);
+	return shared;
+}
+
+void CleanupCertificateCache() {
+	std::lock_guard lock(CertificateCacheMutex);
+	CertificateCache.clear();
 }
 
 } // namespace rtc

src/certificate.hpp

@@ -20,26 +20,50 @@
 #define RTC_CERTIFICATE_H
 
 #include "include.hpp"
+#include "tls.hpp"
 
-#include <gnutls/x509.h>
+#include <future>
+#include <tuple>
 
 namespace rtc {
 
 class Certificate {
 public:
-	Certificate(gnutls_x509_crt_t crt, gnutls_x509_privkey_t privkey);
 	Certificate(string crt_pem, string key_pem);
 
-	string fingerprint() const;
+#if USE_GNUTLS
+	Certificate(gnutls_x509_crt_t crt, gnutls_x509_privkey_t privkey);
 	gnutls_certificate_credentials_t credentials() const;
+#else
+	Certificate(std::shared_ptr<X509> x509, std::shared_ptr<EVP_PKEY> pkey);
+	std::tuple<X509 *, EVP_PKEY *> credentials() const;
+#endif
+
+	string fingerprint() const;
 
 private:
+#if USE_GNUTLS
 	std::shared_ptr<gnutls_certificate_credentials_t> mCredentials;
+#else
+	std::shared_ptr<X509> mX509;
+	std::shared_ptr<EVP_PKEY> mPKey;
+#endif
+
 	string mFingerprint;
 };
 
+#if USE_GNUTLS
 string make_fingerprint(gnutls_x509_crt_t crt);
-std::shared_ptr<Certificate> make_certificate(const string &commonName);
+#else
+string make_fingerprint(X509 *x509);
+#endif
+
+using certificate_ptr = std::shared_ptr<Certificate>;
+using future_certificate_ptr = std::shared_future<certificate_ptr>;
+
+future_certificate_ptr make_certificate(string commonName = "libdatachannel"); // cached
+
+void CleanupCertificateCache();
 
 } // namespace rtc
 

src/channel.cpp

@@ -20,9 +20,19 @@
 
 namespace rtc {
 
-void Channel::onOpen(std::function<void()> callback) { mOpenCallback = callback; }
+size_t Channel::maxMessageSize() const { return DEFAULT_MAX_MESSAGE_SIZE; }
 
-void Channel::onClosed(std::function<void()> callback) { mClosedCallback = callback; }
+size_t Channel::bufferedAmount() const { return mBufferedAmount; }
+
+size_t Channel::availableAmount() const { return 0; }
+
+void Channel::onOpen(std::function<void()> callback) {
+	mOpenCallback = callback;
+}
+
+void Channel::onClosed(std::function<void()> callback) {
+	mClosedCallback = callback;
+}
 
 void Channel::onError(std::function<void(const string &error)> callback) {
 	mErrorCallback = callback;
@@ -30,6 +40,10 @@ void Channel::onError(std::function<void(const string &error)> callback) {
 
 void Channel::onMessage(std::function<void(const std::variant<binary, string> &data)> callback) {
 	mMessageCallback = callback;
+
+	// Pass pending messages
+	while (auto message = receive())
+		mMessageCallback(*message);
 }
 
 void Channel::onMessage(std::function<void(const binary &data)> binaryCallback,
@@ -39,24 +53,48 @@ void Channel::onMessage(std::function<void(const binary &data)> binaryCallback,
 	});
 }
 
-void Channel::triggerOpen(void) {
+void Channel::onBufferedAmountLow(std::function<void()> callback) {
-	if (mOpenCallback)
+	mBufferedAmountLowCallback = callback;
-		mOpenCallback();
 }
 
-void Channel::triggerClosed(void) {
+void Channel::setBufferedAmountLowThreshold(size_t amount) { mBufferedAmountLowThreshold = amount; }
-	if (mClosedCallback)
+
-		mClosedCallback();
+void Channel::onAvailable(std::function<void()> callback) {
+	mAvailableCallback = callback;
 }
 
-void Channel::triggerError(const string &error) {
+void Channel::triggerOpen() { mOpenCallback(); }
-	if (mErrorCallback)
+
-		mErrorCallback(error);
+void Channel::triggerClosed() { mClosedCallback(); }
+
+void Channel::triggerError(const string &error) { mErrorCallback(error); }
+
+void Channel::triggerAvailable(size_t count) {
+	if (count == 1)
+		mAvailableCallback();
+
+	while (mMessageCallback && count--) {
+		auto message = receive();
+		if (!message)
+			break;
+		mMessageCallback(*message);
+	}
 }
 
-void Channel::triggerMessage(const std::variant<binary, string> &data) {
+void Channel::triggerBufferedAmount(size_t amount) {
-	if (mMessageCallback)
+	size_t previous = mBufferedAmount.exchange(amount);
-		mMessageCallback(data);
+	size_t threshold = mBufferedAmountLowThreshold.load();
+	if (previous > threshold && amount <= threshold)
+		mBufferedAmountLowCallback();
+}
+
+void Channel::resetCallbacks() {
+	mOpenCallback = nullptr;
+	mClosedCallback = nullptr;
+	mErrorCallback = nullptr;
+	mMessageCallback = nullptr;
+	mAvailableCallback = nullptr;
+	mBufferedAmountLowCallback = nullptr;
 }
 
 } // namespace rtc

src/configuration.cpp

@@ -18,22 +18,74 @@
 
 #include "configuration.hpp"
 
+#include <regex>
+
 namespace rtc {
 
-using std::to_string;
+IceServer::IceServer(const string &url) {
+	// Modified regex from RFC 3986, see https://tools.ietf.org/html/rfc3986#appendix-B
+	static const char *rs =
+	    R"(^(([^:.@/?#]+):)?(/{0,2}((([^:@]*)(:([^@]*))?)@)?(([^:/?#]*)(:([^/?#]*))?))?([^?#]*)(\?([^#]*))?(#(.*))?)";
+	static const std::regex r(rs, std::regex::extended);
 
-IceServer::IceServer(const string &host) {
+	std::smatch m;
-	if(size_t pos = host.rfind(':'); pos != string::npos) {
+	if (!std::regex_match(url, m, r) || m[10].length() == 0)
-		hostname = host.substr(0, pos);
+		throw std::invalid_argument("Invalid ICE server URL: " + url);
-		service = host.substr(pos + 1);
+
-	} else {
+	std::vector<std::optional<string>> opt(m.size());
-		hostname = host;
+	std::transform(m.begin(), m.end(), opt.begin(), [](const auto &sm) {
-		service = "3478"; // STUN UDP port
+		return sm.length() > 0 ? std::make_optional(string(sm)) : nullopt;
+	});
+
+	string scheme = opt[2].value_or("stun");
+	relayType = RelayType::TurnUdp;
+	if (scheme == "stun" || scheme == "STUN")
+		type = Type::Stun;
+	else if (scheme == "turn" || scheme == "TURN")
+		type = Type::Turn;
+	else if (scheme == "turns" || scheme == "TURNS") {
+		type = Type::Turn;
+		relayType = RelayType::TurnTls;
+	} else
+		throw std::invalid_argument("Unknown ICE server protocol: " + scheme);
+
+	if (auto &query = opt[15]) {
+		if (query->find("transport=udp") != string::npos)
+			relayType = RelayType::TurnUdp;
+		if (query->find("transport=tcp") != string::npos)
+			relayType = RelayType::TurnTcp;
+		if (query->find("transport=tls") != string::npos)
+			relayType = RelayType::TurnTls;
 	}
+
+	username = opt[6].value_or("");
+	password = opt[8].value_or("");
+	hostname = opt[10].value();
+	service = opt[12].value_or(relayType == RelayType::TurnTls ? "5349" : "3478");
+
+	while (!hostname.empty() && hostname.front() == '[')
+		hostname.erase(hostname.begin());
+	while (!hostname.empty() && hostname.back() == ']')
+		hostname.pop_back();
 }
 
-IceServer::IceServer(const string &hostname_, uint16_t port_) : IceServer(hostname_, to_string(port_)) {}
+IceServer::IceServer(string hostname_, uint16_t port_)
+    : IceServer(std::move(hostname_), std::to_string(port_)) {}
 
-IceServer::IceServer(const string &hostname_, const string &service_) : hostname(hostname_), service(service_) {}
+IceServer::IceServer(string hostname_, string service_)
+    : hostname(std::move(hostname_)), service(std::move(service_)), type(Type::Stun) {}
+
+IceServer::IceServer(string hostname_, uint16_t port_, string username_, string password_,
+                     RelayType relayType_)
+    : IceServer(hostname_, std::to_string(port_), std::move(username_), std::move(password_),
+                relayType_) {}
+
+IceServer::IceServer(string hostname_, string service_, string username_, string password_,
+                     RelayType relayType_)
+    : hostname(std::move(hostname_)), service(std::move(service_)), type(Type::Turn),
+      username(std::move(username_)), password(std::move(password_)), relayType(relayType_) {}
+
+ProxyServer::ProxyServer(Type type_, string ip_, uint16_t port_, string username_, string password_)
+    : type(type_), ip(ip_), port(port_), username(username_), password(password_) {}
 
 } // namespace rtc

src/datachannel.cpp

@@ -17,12 +17,20 @@
  */
 
 #include "datachannel.hpp"
+#include "include.hpp"
 #include "peerconnection.hpp"
 #include "sctptransport.hpp"
 
+#ifdef _WIN32
+#include <winsock2.h>
+#else
+#include <arpa/inet.h>
+#endif
+
 namespace rtc {
 
 using std::shared_ptr;
+using std::weak_ptr;
 
 // Messages for the DataChannel establishment protocol
 // See https://tools.ietf.org/html/draft-ietf-rtcweb-data-protocol-09
@@ -57,48 +65,23 @@ struct CloseMessage {
 };
 #pragma pack(pop)
 
-DataChannel::DataChannel(unsigned int stream, string label, string protocol,
+const size_t RECV_QUEUE_LIMIT = 1024 * 1024; // 1 MiB
-                         Reliability reliability)
-    : mStream(stream), mLabel(std::move(label)), mProtocol(std::move(protocol)),
-      mReliability(std::make_shared<Reliability>(std::move(reliability))) {}
 
-DataChannel::DataChannel(unsigned int stream, shared_ptr<SctpTransport> sctpTransport)
+DataChannel::DataChannel(weak_ptr<PeerConnection> pc, unsigned int stream, string label,
-    : mStream(stream), mSctpTransport(sctpTransport),
+                         string protocol, Reliability reliability)
-      mReliability(std::make_shared<Reliability>()) {}
+    : mPeerConnection(pc), mStream(stream), mLabel(std::move(label)),
+      mProtocol(std::move(protocol)),
+      mReliability(std::make_shared<Reliability>(std::move(reliability))),
+      mRecvQueue(RECV_QUEUE_LIMIT, message_size_func) {}
 
-DataChannel::~DataChannel() { close(); }
+DataChannel::DataChannel(weak_ptr<PeerConnection> pc, weak_ptr<SctpTransport> transport,
+                         unsigned int stream)
+    : mPeerConnection(pc), mSctpTransport(transport), mStream(stream),
+      mReliability(std::make_shared<Reliability>()),
+      mRecvQueue(RECV_QUEUE_LIMIT, message_size_func) {}
 
-void DataChannel::close() {
+DataChannel::~DataChannel() {
-	mIsOpen = false;
+	close();
-	if (!mIsClosed) {
-		mIsClosed = true;
-		if (mSctpTransport)
-			mSctpTransport->reset(mStream);
-	}
-}
-
-void DataChannel::send(const std::variant<binary, string> &data) {
-	if (mIsClosed || !mSctpTransport)
-		return;
-
-	std::visit(
-	    [this](const auto &d) {
-		    using T = std::decay_t<decltype(d)>;
-		    constexpr auto type = std::is_same_v<T, string> ? Message::String : Message::Binary;
-		    auto *b = reinterpret_cast<const byte *>(d.data());
-		    // Before the ACK has been received on a DataChannel, all messages must be sent ordered
-		    auto reliability = mIsOpen ? mReliability : nullptr;
-		    mSctpTransport->send(make_message(b, b + d.size(), type, mStream, reliability));
-	    },
-	    data);
-}
-
-void DataChannel::send(const byte *data, size_t size) {
-	if (mIsClosed || !mSctpTransport)
-		return;
-
-	auto reliability = mIsOpen ? mReliability : nullptr;
-	mSctpTransport->send(make_message(data, data + size, Message::Binary, mStream, reliability));
 }
 
 unsigned int DataChannel::stream() const { return mStream; }
@@ -109,12 +92,81 @@ string DataChannel::protocol() const { return mProtocol; }
 
 Reliability DataChannel::reliability() const { return *mReliability; }
 
+void DataChannel::close() {
+	mIsClosed = true;
+	if (mIsOpen.exchange(false))
+		if (auto transport = mSctpTransport.lock())
+			transport->close(mStream);
+
+	mSctpTransport.reset();
+	resetCallbacks();
+}
+
+void DataChannel::remoteClose() {
+	if (!mIsClosed.exchange(true))
+		triggerClosed();
+
+	mIsOpen = false;
+	mSctpTransport.reset();
+}
+
+bool DataChannel::send(const std::variant<binary, string> &data) {
+	return std::visit(
+	    [&](const auto &d) {
+		    using T = std::decay_t<decltype(d)>;
+		    constexpr auto type = std::is_same_v<T, string> ? Message::String : Message::Binary;
+		    auto *b = reinterpret_cast<const byte *>(d.data());
+		    return outgoing(std::make_shared<Message>(b, b + d.size(), type));
+	    },
+	    data);
+}
+
+bool DataChannel::send(const byte *data, size_t size) {
+	return outgoing(std::make_shared<Message>(data, data + size, Message::Binary));
+}
+
+std::optional<std::variant<binary, string>> DataChannel::receive() {
+	while (!mRecvQueue.empty()) {
+		auto message = *mRecvQueue.pop();
+		switch (message->type) {
+		case Message::Control: {
+			auto raw = reinterpret_cast<const uint8_t *>(message->data());
+			if (raw[0] == MESSAGE_CLOSE)
+				remoteClose();
+			break;
+		}
+		case Message::String:
+			return std::make_optional(
+			    string(reinterpret_cast<const char *>(message->data()), message->size()));
+		case Message::Binary:
+			return std::make_optional(std::move(*message));
+		default:
+			// Ignore
+			break;
+		}
+	}
+
+	return nullopt;
+}
+
 bool DataChannel::isOpen(void) const { return mIsOpen; }
 
 bool DataChannel::isClosed(void) const { return mIsClosed; }
 
-void DataChannel::open(shared_ptr<SctpTransport> sctpTransport) {
+size_t DataChannel::maxMessageSize() const {
-	mSctpTransport = sctpTransport;
+	size_t remoteMax = DEFAULT_MAX_MESSAGE_SIZE;
+	if (auto pc = mPeerConnection.lock())
+		if (auto description = pc->remoteDescription())
+			if (auto maxMessageSize = description->maxMessageSize())
+				remoteMax = *maxMessageSize > 0 ? *maxMessageSize : LOCAL_MAX_MESSAGE_SIZE;
+
+	return std::min(remoteMax, LOCAL_MAX_MESSAGE_SIZE);
+}
+
+size_t DataChannel::availableAmount() const { return mRecvQueue.amount(); }
+
+void DataChannel::open(shared_ptr<SctpTransport> transport) {
+	mSctpTransport = transport;
 
 	uint8_t channelType = static_cast<uint8_t>(mReliability->type);
 	if (mReliability->unordered)
@@ -141,10 +193,30 @@ void DataChannel::open(shared_ptr<SctpTransport> sctpTransport) {
 	std::copy(mLabel.begin(), mLabel.end(), end);
 	std::copy(mProtocol.begin(), mProtocol.end(), end + mLabel.size());
 
-	mSctpTransport->send(make_message(buffer.begin(), buffer.end(), Message::Control, mStream));
+	transport->send(make_message(buffer.begin(), buffer.end(), Message::Control, mStream));
+}
+
+bool DataChannel::outgoing(message_ptr message) {
+	if (mIsClosed)
+		throw std::runtime_error("DataChannel is closed");
+
+	if (message->size() > maxMessageSize())
+		throw std::runtime_error("Message size exceeds limit");
+
+	auto transport = mSctpTransport.lock();
+	if (!transport)
+		throw std::runtime_error("DataChannel has no transport");
+
+	// Before the ACK has been received on a DataChannel, all messages must be sent ordered
+	message->reliability = mIsOpen ? mReliability : nullptr;
+	message->stream = mStream;
+	return transport->send(message);
 }
 
 void DataChannel::incoming(message_ptr message) {
+	if (!message)
+		return;
+
 	switch (message->type) {
 	case Message::Control: {
 		auto raw = reinterpret_cast<const uint8_t *>(message->data());
@@ -153,16 +225,14 @@ void DataChannel::incoming(message_ptr message) {
 			processOpenMessage(message);
 			break;
 		case MESSAGE_ACK:
-			if (!mIsOpen) {
+			if (!mIsOpen.exchange(true)) {
-				mIsOpen = true;
 				triggerOpen();
 			}
 			break;
 		case MESSAGE_CLOSE:
-			if (mIsOpen) {
+			// The close message will be processed in-order in receive()
-				close();
+			mRecvQueue.push(message);
-				triggerClosed();
+			triggerAvailable(mRecvQueue.size());
-			}
 			break;
 		default:
 			// Ignore
@@ -170,18 +240,22 @@ void DataChannel::incoming(message_ptr message) {
 		}
 		break;
 	}
-	case Message::String: {
+	case Message::String:
-		triggerMessage(string(reinterpret_cast<const char *>(message->data()), message->size()));
+	case Message::Binary:
+		mRecvQueue.push(message);
+		triggerAvailable(mRecvQueue.size());
 		break;
-	}
+	default:
-	case Message::Binary: {
+		// Ignore
-		triggerMessage(*message);
 		break;
 	}
-	}
 }
 
 void DataChannel::processOpenMessage(message_ptr message) {
+	auto transport = mSctpTransport.lock();
+	if (!transport)
+		throw std::runtime_error("DataChannel has no transport");
+
 	if (message->size() < sizeof(OpenMessage))
 		throw std::invalid_argument("DataChannel open message too small");
 
@@ -218,7 +292,7 @@ void DataChannel::processOpenMessage(message_ptr message) {
 	auto &ack = *reinterpret_cast<AckMessage *>(buffer.data());
 	ack.type = MESSAGE_ACK;
 
-	mSctpTransport->send(make_message(buffer.begin(), buffer.end(), Message::Control, mStream));
+	transport->send(make_message(buffer.begin(), buffer.end(), Message::Control, mStream));
 
 	mIsOpen = true;
 	triggerOpen();

src/description.cpp

@@ -29,7 +29,7 @@ using std::string;
 
 namespace {
 
-inline bool hasprefix(const string &str, const string &prefix) {
+inline bool match_prefix(const string &str, const string &prefix) {
 	return str.size() >= prefix.size() &&
 	       std::mismatch(prefix.begin(), prefix.end(), str.begin()).first == prefix.end();
 }
@@ -45,12 +45,14 @@ inline void trim_end(string &str) {
 namespace rtc {
 
 Description::Description(const string &sdp, const string &typeString)
-    : Description(sdp, stringToType(typeString), Description::Role::ActPass) {}
+    : Description(sdp, stringToType(typeString)) {}
+
+Description::Description(const string &sdp, Type type) : Description(sdp, type, Role::ActPass) {}
 
 Description::Description(const string &sdp, Type type, Role role)
-    : mType(type), mRole(role), mMid("0"), mIceUfrag("0"), mIcePwd("0"), mTrickle(true) {
+    : mType(Type::Unspec), mRole(role) {
-	if (mType == Type::Answer && mRole == Role::ActPass)
+	mData.mid = "data";
-		mRole = Role::Passive; // ActPass is illegal for an answer, so default to passive
+	hintType(type);
 
 	auto seed = std::chrono::system_clock::now().time_since_epoch().count();
 	std::default_random_engine generator(seed);
@@ -58,35 +60,79 @@ Description::Description(const string &sdp, Type type, Role role)
 	mSessionId = std::to_string(uniform(generator));
 
 	std::istringstream ss(sdp);
+	std::optional<Media> currentMedia;
+
+	bool finished;
+	do {
 		string line;
-	while (std::getline(ss, line)) {
+		finished = !std::getline(ss, line) && line.empty();
 		trim_end(line);
-		if (hasprefix(line, "a=setup:")) {
+
-			const string setup = line.substr(line.find(':') + 1);
+		// Media description line (aka m-line)
-			if (setup == "active")
+		if (finished || match_prefix(line, "m=")) {
+			if (currentMedia) {
+				if (!currentMedia->mid.empty()) {
+					if (currentMedia->type == "application")
+						mData.mid = currentMedia->mid;
+					else
+						mMedia.emplace(currentMedia->mid, std::move(*currentMedia));
+
+				} else if (line.find(" ICE/SDP") != string::npos) {
+					PLOG_WARNING << "SDP \"m=\" line has no corresponding mid, ignoring";
+				}
+			}
+			if (!finished)
+				currentMedia.emplace(Media(line.substr(2)));
+
+			// Attribute line
+		} else if (match_prefix(line, "a=")) {
+			string attr = line.substr(2);
+
+			string key, value;
+			if (size_t separator = attr.find(':'); separator != string::npos) {
+				key = attr.substr(0, separator);
+				value = attr.substr(separator + 1);
+			} else {
+				key = attr;
+			}
+
+			if (key == "mid") {
+				if (currentMedia)
+					currentMedia->mid = value;
+
+			} else if (key == "setup") {
+				if (value == "active")
 					mRole = Role::Active;
-			else if (setup == "passive")
+				else if (value == "passive")
 					mRole = Role::Passive;
 				else
 					mRole = Role::ActPass;
-		} else if (hasprefix(line, "a=mid:")) {
+
-			mMid = line.substr(line.find(':') + 1);
+			} else if (key == "fingerprint") {
-		} else if (hasprefix(line, "a=fingerprint:sha-256")) {
+				if (match_prefix(value, "sha-256 ")) {
-			mFingerprint = line.substr(line.find(' ') + 1);
+					mFingerprint = value.substr(8);
-			std::transform(mFingerprint->begin(), mFingerprint->end(), mFingerprint->begin(),
+					std::transform(mFingerprint->begin(), mFingerprint->end(),
-						   [](char c) { return std::toupper(c); });
+					               mFingerprint->begin(), [](char c) { return std::toupper(c); });
-		} else if (hasprefix(line, "a=ice-ufrag")) {
+				} else {
-			mIceUfrag = line.substr(line.find(':') + 1);
+					PLOG_WARNING << "Unknown SDP fingerprint type: " << value;
-		} else if (hasprefix(line, "a=ice-pwd")) {
+				}
-			mIcePwd = line.substr(line.find(':') + 1);
+			} else if (key == "ice-ufrag") {
-		} else if (hasprefix(line, "a=sctp-port")) {
+				mIceUfrag = value;
-			mSctpPort = uint16_t(std::stoul(line.substr(line.find(':') + 1)));
+			} else if (key == "ice-pwd") {
-		} else if (hasprefix(line, "a=candidate")) {
+				mIcePwd = value;
-			mCandidates.emplace_back(Candidate(line.substr(2), mMid));
+			} else if (key == "sctp-port") {
-		} else if (hasprefix(line, "a=end-of-candidates")) {
+				mData.sctpPort = uint16_t(std::stoul(value));
-			mTrickle = false;
+			} else if (key == "max-message-size") {
+				mData.maxMessageSize = size_t(std::stoul(value));
+			} else if (key == "candidate") {
+				addCandidate(Candidate(attr, currentMedia ? currentMedia->mid : mData.mid));
+			} else if (key == "end-of-candidates") {
+				mEnded = true;
+			} else if (currentMedia) {
+				currentMedia->attributes.emplace_back(line.substr(2));
 			}
 		}
+	} while (!finished);
 }
 
 Description::Type Description::type() const { return mType; }
@@ -97,57 +143,134 @@ Description::Role Description::role() const { return mRole; }
 
 string Description::roleString() const { return roleToString(mRole); }
 
-string Description::mid() const { return mMid; }
+string Description::dataMid() const { return mData.mid; }
 
 std::optional<string> Description::fingerprint() const { return mFingerprint; }
 
-std::optional<uint16_t> Description::sctpPort() const { return mSctpPort; }
+std::optional<uint16_t> Description::sctpPort() const { return mData.sctpPort; }
+
+std::optional<size_t> Description::maxMessageSize() const { return mData.maxMessageSize; }
+
+bool Description::ended() const { return mEnded; }
+
+void Description::hintType(Type type) {
+	if (mType == Type::Unspec) {
+		mType = type;
+		if (mType == Type::Answer && mRole == Role::ActPass)
+			mRole = Role::Passive; // ActPass is illegal for an answer, so default to passive
+	}
+}
 
 void Description::setFingerprint(string fingerprint) {
 	mFingerprint.emplace(std::move(fingerprint));
 }
 
-void Description::setSctpPort(uint16_t port) { mSctpPort.emplace(port); }
+void Description::setSctpPort(uint16_t port) { mData.sctpPort.emplace(port); }
+
+void Description::setMaxMessageSize(size_t size) { mData.maxMessageSize.emplace(size); }
 
 void Description::addCandidate(Candidate candidate) {
 	mCandidates.emplace_back(std::move(candidate));
 }
 
-void Description::endCandidates() { mTrickle = false; }
+void Description::endCandidates() { mEnded = true; }
 
-Description::operator string() const {
+std::vector<Candidate> Description::extractCandidates() {
+	std::vector<Candidate> result;
+	std::swap(mCandidates, result);
+	mEnded = false;
+	return result;
+}
+
+bool Description::hasMedia() const { return !mMedia.empty(); }
+
+void Description::addMedia(const Description &source) {
+	for (auto [mid, media] : source.mMedia)
+		if (mid != mData.mid)
+			mMedia.emplace(mid, media);
+		else
+			PLOG_WARNING << "Media mid \"" << mid << "\" is the same as data mid, ignoring";
+}
+
+Description::operator string() const { return generateSdp("\r\n"); }
+
+string Description::generateSdp(const string &eol) const {
 	if (!mFingerprint)
-		throw std::logic_error("Fingerprint must be set to generate a SDP");
+		throw std::logic_error("Fingerprint must be set to generate an SDP string");
 
 	std::ostringstream sdp;
-	sdp << "v=0\n";
-	sdp << "o=- " << mSessionId << " 0 IN IP4 0.0.0.0\n";
-	sdp << "s=-\n";
-	sdp << "t=0 0\n";
-	sdp << "m=application 9 UDP/DTLS/SCTP webrtc-datachannel\n";
-	sdp << "c=IN IP4 0.0.0.0\n";
-	sdp << "a=ice-ufrag:" << mIceUfrag << "\n";
-	sdp << "a=ice-pwd:" << mIcePwd << "\n";
-	if (mTrickle)
-		sdp << "a=ice-options:trickle\n";
-	sdp << "a=mid:" << mMid << "\n";
-	sdp << "a=setup:" << roleToString(mRole) << "\n";
-	sdp << "a=dtls-id:1\n";
-	if (mFingerprint)
-		sdp << "a=fingerprint:sha-256 " << *mFingerprint << "\n";
-	if (mSctpPort)
-		sdp << "a=sctp-port:" << *mSctpPort << "\n";
 
-	for (const auto &candidate : mCandidates) {
+	// Header
-		sdp << string(candidate) << "\n";
+	sdp << "v=0" << eol;
+	sdp << "o=- " << mSessionId << " 0 IN IP4 127.0.0.1" << eol;
+	sdp << "s=-" << eol;
+	sdp << "t=0 0" << eol;
+
+	// Bundle
+	// see Negotiating Media Multiplexing Using the Session Description Protocol
+	// https://tools.ietf.org/html/draft-ietf-mmusic-sdp-bundle-negotiation-54
+	sdp << "a=group:BUNDLE";
+	for (const auto &[mid, _] : mMedia)
+		sdp << " " << mid;
+	sdp << " " << mData.mid << eol;
+
+	// Data
+	const string dataDescription = "UDP/DTLS/SCTP webrtc-datachannel";
+	sdp << "m=application" << ' ' << (!mMedia.empty() ? 0 : 9) << ' ' << dataDescription << eol;
+	sdp << "c=IN IP4 0.0.0.0" << eol;
+	if (!mMedia.empty())
+		sdp << "a=bundle-only" << eol;
+	sdp << "a=mid:" << mData.mid << eol;
+	if (mData.sctpPort)
+		sdp << "a=sctp-port:" << *mData.sctpPort << eol;
+	if (mData.maxMessageSize)
+		sdp << "a=max-message-size:" << *mData.maxMessageSize << eol;
+
+	// Non-data media
+	if (!mMedia.empty()) {
+		// Lip-sync
+		sdp << "a=group:LS";
+		for (const auto &[mid, _] : mMedia)
+			sdp << " " << mid;
+		sdp << eol;
+
+		// Descriptions and attributes
+		for (const auto &[_, media] : mMedia) {
+			sdp << "m=" << media.type << ' ' << 0 << ' ' << media.description << eol;
+			sdp << "c=IN IP4 0.0.0.0" << eol;
+			sdp << "a=bundle-only" << eol;
+			sdp << "a=mid:" << media.mid << eol;
+			for (const auto &attr : media.attributes)
+				sdp << "a=" << attr << eol;
+		}
 	}
 
-	if (!mTrickle)
+	// Common
-		sdp << "a=end-of-candidates\n";
+	sdp << "a=ice-options:trickle" << eol;
+	sdp << "a=ice-ufrag:" << mIceUfrag << eol;
+	sdp << "a=ice-pwd:" << mIcePwd << eol;
+	sdp << "a=setup:" << roleToString(mRole) << eol;
+	sdp << "a=dtls-id:1" << eol;
+	if (mFingerprint)
+		sdp << "a=fingerprint:sha-256 " << *mFingerprint << eol;
+
+	// Candidates
+	for (const auto &candidate : mCandidates)
+		sdp << string(candidate) << eol;
+	if (mEnded)
+		sdp << "a=end-of-candidates" << eol;
 
 	return sdp.str();
 }
 
+Description::Media::Media(const string &mline) {
+	size_t p = mline.find(' ');
+	this->type = mline.substr(0, p);
+	if (p != string::npos)
+		if (size_t q = mline.find(' ', p + 1); q != string::npos)
+			this->description = mline.substr(q + 1);
+}
+
 Description::Type Description::stringToType(const string &typeString) {
 	if (typeString == "offer")
 		return Type::Offer;

src/dtlssrtptransport.cpp

@@ -0,0 +1,205 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "dtlssrtptransport.hpp"
+#include "tls.hpp"
+
+#if RTC_ENABLE_MEDIA
+
+#include <cstring>
+#include <exception>
+
+using std::shared_ptr;
+using std::to_integer;
+using std::to_string;
+
+namespace rtc {
+
+void DtlsSrtpTransport::Init() { srtp_init(); }
+
+void DtlsSrtpTransport::Cleanup() { srtp_shutdown(); }
+
+DtlsSrtpTransport::DtlsSrtpTransport(std::shared_ptr<IceTransport> lower,
+                                     shared_ptr<Certificate> certificate,
+                                     verifier_callback verifierCallback,
+                                     message_callback srtpRecvCallback,
+                                     state_callback stateChangeCallback)
+    : DtlsTransport(lower, certificate, std::move(verifierCallback),
+                    std::move(stateChangeCallback)),
+      mSrtpRecvCallback(std::move(srtpRecvCallback)) { // distinct from Transport recv callback
+
+	PLOG_DEBUG << "Initializing SRTP transport";
+
+#if USE_GNUTLS
+	PLOG_DEBUG << "Initializing DTLS-SRTP transport (GnuTLS)";
+	gnutls::check(gnutls_srtp_set_profile(mSession, GNUTLS_SRTP_AES128_CM_HMAC_SHA1_80),
+	              "Failed to set SRTP profile");
+#else
+	PLOG_DEBUG << "Initializing DTLS-SRTP transport (OpenSSL)";
+	openssl::check(SSL_set_tlsext_use_srtp(mSsl, "SRTP_AES128_CM_SHA1_80"),
+	               "Failed to set SRTP profile");
+#endif
+}
+
+DtlsSrtpTransport::~DtlsSrtpTransport() {
+	stop();
+
+	if (mCreated)
+		srtp_dealloc(mSrtp);
+}
+
+bool DtlsSrtpTransport::send(message_ptr message) {
+	if (!message)
+		return false;
+
+	int size = message->size();
+	PLOG_VERBOSE << "Send size=" << size;
+
+	// srtp_protect() assumes that it can write SRTP_MAX_TRAILER_LEN (for the authentication tag)
+	// into the location in memory immediately following the RTP packet.
+	message->resize(size + SRTP_MAX_TRAILER_LEN);
+	if (srtp_err_status_t err = srtp_protect(mSrtp, message->data(), &size)) {
+		if (err == srtp_err_status_replay_fail)
+			throw std::runtime_error("SRTP packet is a replay");
+		else
+			throw std::runtime_error("SRTP protect error, status=" +
+			                         to_string(static_cast<int>(err)));
+	}
+	PLOG_VERBOSE << "Protected SRTP packet, size=" << size;
+	message->resize(size);
+	outgoing(message);
+	return true;
+}
+
+void DtlsSrtpTransport::incoming(message_ptr message) {
+	int size = message->size();
+	if (size == 0)
+		return;
+
+	// RFC 5764 5.1.2. Reception
+	// The process for demultiplexing a packet is as follows. The receiver looks at the first byte
+	// of the packet. [...] If the value is in between 128 and 191 (inclusive), then the packet is
+	// RTP (or RTCP [...]). If the value is between 20 and 63 (inclusive), the packet is DTLS.
+	uint8_t value = to_integer<uint8_t>(*message->begin());
+
+	if (value >= 128 && value <= 192) {
+		PLOG_VERBOSE << "Incoming DTLS packet, size=" << size;
+		DtlsTransport::incoming(message);
+	} else if (value >= 20 && value <= 64) {
+		PLOG_VERBOSE << "Incoming SRTP packet, size=" << size;
+
+		if (srtp_err_status_t err = srtp_unprotect(mSrtp, message->data(), &size)) {
+			if (err == srtp_err_status_replay_fail)
+				PLOG_WARNING << "Incoming SRTP packet is a replay";
+			else
+				PLOG_WARNING << "SRTP unprotect error, status=" << err;
+			return;
+		}
+		PLOG_VERBOSE << "Unprotected SRTP packet, size=" << size;
+		message->resize(size);
+		mSrtpRecvCallback(message);
+
+	} else {
+		PLOG_WARNING << "Unknown packet type, value=" << value << ", size=" << size;
+	}
+}
+
+void DtlsSrtpTransport::postHandshake() {
+	if (mCreated)
+		return;
+
+	srtp_policy_t inbound = {};
+	srtp_crypto_policy_set_aes_cm_128_hmac_sha1_80(&inbound.rtp);
+	srtp_crypto_policy_set_aes_cm_128_hmac_sha1_80(&inbound.rtcp);
+	inbound.ssrc.type = ssrc_any_inbound;
+
+	srtp_policy_t outbound = {};
+	srtp_crypto_policy_set_aes_cm_128_hmac_sha1_80(&outbound.rtp);
+	srtp_crypto_policy_set_aes_cm_128_hmac_sha1_80(&outbound.rtcp);
+	outbound.ssrc.type = ssrc_any_outbound;
+
+	const size_t materialLen = SRTP_AES_ICM_128_KEY_LEN_WSALT * 2;
+	unsigned char material[materialLen];
+	const unsigned char *clientKey, *clientSalt, *serverKey, *serverSalt;
+
+#if USE_GNUTLS
+	gnutls_datum_t clientKeyDatum, clientSaltDatum, serverKeyDatum, serverSaltDatum;
+	gnutls::check(gnutls_srtp_get_keys(mSession, material, materialLen, &clientKeyDatum,
+	                                   &clientSaltDatum, &serverKeyDatum, &serverSaltDatum),
+	              "Failed to derive SRTP keys");
+
+	if (clientKeyDatum.size != SRTP_AES_128_KEY_LEN)
+		throw std::logic_error("Unexpected SRTP master key length: " +
+		                       to_string(clientKeyDatum.size));
+	if (clientSaltDatum.size != SRTP_SALT_LEN)
+		throw std::logic_error("Unexpected SRTP salt length: " + to_string(clientSaltDatum.size));
+	if (serverKeyDatum.size != SRTP_AES_128_KEY_LEN)
+		throw std::logic_error("Unexpected SRTP master key length: " +
+		                       to_string(serverKeyDatum.size));
+	if (serverSaltDatum.size != SRTP_SALT_LEN)
+		throw std::logic_error("Unexpected SRTP salt size: " + to_string(serverSaltDatum.size));
+
+	clientKey = reinterpret_cast<const unsigned char *>(clientKeyDatum.data);
+	clientSalt = reinterpret_cast<const unsigned char *>(clientSaltDatum.data);
+
+	serverKey = reinterpret_cast<const unsigned char *>(serverKeyDatum.data);
+	serverSalt = reinterpret_cast<const unsigned char *>(serverSaltDatum.data);
+#else
+	// This provides the client write master key, the server write master key, the client write
+	// master salt and the server write master salt in that order.
+	const string label = "EXTRACTOR-dtls_srtp";
+	openssl::check(SSL_export_keying_material(mSsl, material, materialLen, label.c_str(),
+	                                          label.size(), nullptr, 0, 0),
+	               "Failed to derive SRTP keys");
+
+	clientKey = material;
+	clientSalt = clientKey + SRTP_AES_128_KEY_LEN;
+
+	serverKey = material + SRTP_AES_ICM_128_KEY_LEN_WSALT;
+	serverSalt = serverSalt + SRTP_AES_128_KEY_LEN;
+#endif
+
+	unsigned char clientSessionKey[SRTP_AES_ICM_128_KEY_LEN_WSALT];
+	std::memcpy(clientSessionKey, clientKey, SRTP_AES_128_KEY_LEN);
+	std::memcpy(clientSessionKey + SRTP_AES_128_KEY_LEN, clientSalt, SRTP_SALT_LEN);
+
+	unsigned char serverSessionKey[SRTP_AES_ICM_128_KEY_LEN_WSALT];
+	std::memcpy(serverSessionKey, serverKey, SRTP_AES_128_KEY_LEN);
+	std::memcpy(serverSessionKey + SRTP_AES_128_KEY_LEN, serverSalt, SRTP_SALT_LEN);
+
+	if (mIsClient) {
+		inbound.key = serverSessionKey;
+		outbound.key = clientSessionKey;
+	} else {
+		inbound.key = clientSessionKey;
+		outbound.key = serverSessionKey;
+	}
+
+	srtp_policy_t *policies = &inbound;
+	inbound.next = &outbound;
+	outbound.next = nullptr;
+
+	if (srtp_err_status_t err = srtp_create(&mSrtp, policies))
+		throw std::runtime_error("SRTP create failed, status=" + to_string(static_cast<int>(err)));
+
+	mCreated = true;
+}
+
+} // namespace rtc
+
+#endif

src/dtlssrtptransport.hpp

@@ -0,0 +1,57 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_DTLS_SRTP_TRANSPORT_H
+#define RTC_DTLS_SRTP_TRANSPORT_H
+
+#include "dtlstransport.hpp"
+#include "include.hpp"
+
+#if RTC_ENABLE_MEDIA
+
+#include <srtp2/srtp.h>
+
+namespace rtc {
+
+class DtlsSrtpTransport final : public DtlsTransport {
+public:
+	static void Init();
+	static void Cleanup();
+
+	DtlsSrtpTransport(std::shared_ptr<IceTransport> lower, std::shared_ptr<Certificate> certificate,
+	                  verifier_callback verifierCallback, message_callback srtpRecvCallback,
+	                  state_callback stateChangeCallback);
+	~DtlsSrtpTransport();
+
+	bool send(message_ptr message) override;
+
+private:
+	void incoming(message_ptr message) override;
+	void postHandshake() override;
+
+	message_callback mSrtpRecvCallback;
+
+	srtp_t mSrtp;
+	bool mCreated = false;
+};
+
+} // namespace rtc
+
+#endif
+
+#endif

src/dtlstransport.cpp

@@ -19,49 +19,57 @@
 #include "dtlstransport.hpp"
 #include "icetransport.hpp"
 
-#include <cassert>
+#include <chrono>
 #include <cstring>
 #include <exception>
 #include <iostream>
 
-#include <gnutls/dtls.h>
+using namespace std::chrono;
 
 using std::shared_ptr;
 using std::string;
-
+using std::unique_ptr;
-namespace {
+using std::weak_ptr;
-
-static bool check_gnutls(int ret, const string &message = "GnuTLS error") {
-	if (ret < 0) {
-		if (!gnutls_error_is_fatal(ret))
-			return false;
-		throw std::runtime_error(message + ": " + gnutls_strerror(ret));
-	}
-	return true;
-}
-
-} // namespace
 
 namespace rtc {
 
-using std::shared_ptr;
+#if USE_GNUTLS
 
-DtlsTransport::DtlsTransport(shared_ptr<IceTransport> lower, shared_ptr<Certificate> certificate,
+void DtlsTransport::Init() {
-                             verifier_callback verifierCallback,
+	gnutls_global_init(); // optional
-                             state_callback stateChangeCallback)
+}
-    : Transport(lower), mCertificate(certificate), mState(State::Disconnected),
+
+void DtlsTransport::Cleanup() { gnutls_global_deinit(); }
+
+DtlsTransport::DtlsTransport(shared_ptr<IceTransport> lower, certificate_ptr certificate,
+                             verifier_callback verifierCallback, state_callback stateChangeCallback)
+    : Transport(lower, std::move(stateChangeCallback)), mCertificate(certificate),
       mVerifierCallback(std::move(verifierCallback)),
-      mStateChangeCallback(std::move(stateChangeCallback)) {
+      mIsClient(lower->role() == Description::Role::Active) {
-	gnutls_certificate_set_verify_function(mCertificate->credentials(), CertificateCallback);
 
-	bool active = lower->role() == Description::Role::Active;
+	PLOG_DEBUG << "Initializing DTLS transport (GnuTLS)";
-	unsigned int flags = GNUTLS_DATAGRAM | (active ? GNUTLS_CLIENT : GNUTLS_SERVER);
-	check_gnutls(gnutls_init(&mSession, flags));
 
-	const char *priorities = "SECURE128:-VERS-SSL3.0:-VERS-TLS1.0:-ARCFOUR-128";
+	gnutls_certificate_credentials_t creds = mCertificate->credentials();
+	gnutls_certificate_set_verify_function(creds, CertificateCallback);
+
+	unsigned int flags = GNUTLS_DATAGRAM | (mIsClient ? GNUTLS_CLIENT : GNUTLS_SERVER);
+	gnutls::check(gnutls_init(&mSession, flags));
+
+	try {
+		// RFC 8261: SCTP performs segmentation and reassembly based on the path MTU.
+		// Therefore, the DTLS layer MUST NOT use any compression algorithm.
+		// See https://tools.ietf.org/html/rfc8261#section-5
+		const char *priorities = "SECURE128:-VERS-SSL3.0:-ARCFOUR-128:-COMP-ALL:+COMP-NULL";
 		const char *err_pos = NULL;
-	check_gnutls(gnutls_priority_set_direct(mSession, priorities, &err_pos),
+		gnutls::check(gnutls_priority_set_direct(mSession, priorities, &err_pos),
-	             "Unable to set TLS priorities");
+		              "Failed to set TLS priorities");
+
+		gnutls::check(gnutls_credentials_set(mSession, GNUTLS_CRD_CERTIFICATE, creds));
+
+		gnutls_dtls_set_timeouts(mSession,
+		                         1000,   // 1s retransmission timeout recommended by RFC 6347
+		                         30000); // 30s total timeout
+		gnutls_handshake_set_timeout(mSession, 30000);
 
 		gnutls_session_set_ptr(mSession, this);
 		gnutls_transport_set_ptr(mSession, this);
@@ -69,65 +77,115 @@ DtlsTransport::DtlsTransport(shared_ptr<IceTransport> lower, shared_ptr<Certific
 		gnutls_transport_set_pull_function(mSession, ReadCallback);
 		gnutls_transport_set_pull_timeout_function(mSession, TimeoutCallback);
 
-	check_gnutls(
-	    gnutls_credentials_set(mSession, GNUTLS_CRD_CERTIFICATE, mCertificate->credentials()));
-
 		mRecvThread = std::thread(&DtlsTransport::runRecvLoop, this);
+		registerIncoming();
+
+	} catch (...) {
+		gnutls_deinit(mSession);
+		throw;
+	}
 }
 
 DtlsTransport::~DtlsTransport() {
-	mIncomingQueue.stop();
+	stop();
-	if (mRecvThread.joinable())
-		mRecvThread.join();
 
-	gnutls_bye(mSession, GNUTLS_SHUT_RDWR);
 	gnutls_deinit(mSession);
 }
 
-DtlsTransport::State DtlsTransport::state() const { return mState; }
+bool DtlsTransport::stop() {
-
+	if (!Transport::stop())
-bool DtlsTransport::send(message_ptr message) {
-	if (!message)
 		return false;
 
-	while (true) {
+	PLOG_DEBUG << "Stopping DTLS recv thread";
-		ssize_t ret = gnutls_record_send(mSession, message->data(), message->size());
+	mIncomingQueue.stop();
-		if (check_gnutls(ret)) {
+	mRecvThread.join();
-			return ret > 0;
+	return true;
-		}
-	}
 }
 
-void DtlsTransport::incoming(message_ptr message) { mIncomingQueue.push(message); }
+bool DtlsTransport::send(message_ptr message) {
+	if (!message || state() != State::Connected)
+		return false;
 
-void DtlsTransport::changeState(State state) {
+	PLOG_VERBOSE << "Send size=" << message->size();
-	mState = state;
+
-	mStateChangeCallback(state);
+	ssize_t ret;
+	do {
+		ret = gnutls_record_send(mSession, message->data(), message->size());
+	} while (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN);
+
+	if (ret == GNUTLS_E_LARGE_PACKET)
+		return false;
+
+	return gnutls::check(ret);
+}
+
+void DtlsTransport::incoming(message_ptr message) {
+	if (!message) {
+		mIncomingQueue.stop();
+		return;
+	}
+
+	PLOG_VERBOSE << "Incoming size=" << message->size();
+	mIncomingQueue.push(message);
+}
+
+void DtlsTransport::postHandshake() {
+	// Dummy
 }
 
 void DtlsTransport::runRecvLoop() {
+	const size_t maxMtu = 4096;
+
+	// Handshake loop
 	try {
 		changeState(State::Connecting);
+		gnutls_dtls_set_mtu(mSession, 1280 - 40 - 8); // min MTU over UDP/IPv6
+
+		int ret;
+		do {
+			ret = gnutls_handshake(mSession);
+
+			if (ret == GNUTLS_E_LARGE_PACKET)
+				throw std::runtime_error("MTU is too low");
+
+		} while (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN ||
+		         !gnutls::check(ret, "DTLS handshake failed"));
+
+		// RFC 8261: DTLS MUST support sending messages larger than the current path MTU
+		// See https://tools.ietf.org/html/rfc8261#section-5
+		gnutls_dtls_set_mtu(mSession, maxMtu + 1);
 
-		while (!check_gnutls(gnutls_handshake(mSession), "TLS handshake failed")) {
-		}
 	} catch (const std::exception &e) {
-		std::cerr << "DTLS handshake: " << e.what() << std::endl;
+		PLOG_ERROR << "DTLS handshake: " << e.what();
 		changeState(State::Failed);
 		return;
 	}
 
+	// Receive loop
 	try {
+		PLOG_INFO << "DTLS handshake finished";
 		changeState(State::Connected);
+		postHandshake();
 
-		const size_t bufferSize = 2048;
+		const size_t bufferSize = maxMtu;
 		char buffer[bufferSize];
 
 		while (true) {
-			ssize_t ret = gnutls_record_recv(mSession, buffer, bufferSize);
+			ssize_t ret;
-			if (check_gnutls(ret)) {
+			do {
+				ret = gnutls_record_recv(mSession, buffer, bufferSize);
+			} while (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN);
+
+			// Consider premature termination as remote closing
+			if (ret == GNUTLS_E_PREMATURE_TERMINATION) {
+				PLOG_DEBUG << "DTLS connection terminated";
+				break;
+			}
+
+			if (gnutls::check(ret)) {
 				if (ret == 0) {
 					// Closed
+					PLOG_DEBUG << "DTLS connection cleanly closed";
 					break;
 				}
 				auto *b = reinterpret_cast<byte *>(buffer);
@@ -136,9 +194,12 @@ void DtlsTransport::runRecvLoop() {
 		}
 
 	} catch (const std::exception &e) {
-		std::cerr << "DTLS recv: " << e.what() << std::endl;
+		PLOG_ERROR << "DTLS recv: " << e.what();
 	}
 
+	gnutls_bye(mSession, GNUTLS_SHUT_RDWR);
+
+	PLOG_INFO << "DTLS closed";
 	changeState(State::Disconnected);
 	recv(nullptr);
 }
@@ -157,7 +218,7 @@ int DtlsTransport::CertificateCallback(gnutls_session_t session) {
 	}
 
 	gnutls_x509_crt_t crt;
-	check_gnutls(gnutls_x509_crt_init(&crt));
+	gnutls::check(gnutls_x509_crt_init(&crt));
 	int ret = gnutls_x509_crt_import(crt, &array[0], GNUTLS_X509_FMT_DER);
 	if (ret != GNUTLS_E_SUCCESS) {
 		gnutls_x509_crt_deinit(crt);
@@ -183,22 +244,313 @@ ssize_t DtlsTransport::WriteCallback(gnutls_transport_ptr_t ptr, const void *dat
 
 ssize_t DtlsTransport::ReadCallback(gnutls_transport_ptr_t ptr, void *data, size_t maxlen) {
 	DtlsTransport *t = static_cast<DtlsTransport *>(ptr);
-	auto next = t->mIncomingQueue.pop();
+	if (auto next = t->mIncomingQueue.pop()) {
-	auto message = next ? *next : nullptr;
+		auto message = *next;
-	if (!message) {
-		// Closed
-		gnutls_transport_set_errno(t->mSession, 0);
-		return 0;
-	}
-
 		ssize_t len = std::min(maxlen, message->size());
 		std::memcpy(data, message->data(), len);
 		gnutls_transport_set_errno(t->mSession, 0);
 		return len;
+	}
+	// Closed
+	gnutls_transport_set_errno(t->mSession, 0);
+	return 0;
 }
 
 int DtlsTransport::TimeoutCallback(gnutls_transport_ptr_t ptr, unsigned int ms) {
-	return 1; // So ReadCallback is called
+	DtlsTransport *t = static_cast<DtlsTransport *>(ptr);
+	t->mIncomingQueue.wait(ms != GNUTLS_INDEFINITE_TIMEOUT ? std::make_optional(milliseconds(ms))
+	                                                       : nullopt);
+	return !t->mIncomingQueue.empty() ? 1 : 0;
 }
 
+#else // USE_GNUTLS==0
+
+BIO_METHOD *DtlsTransport::BioMethods = NULL;
+int DtlsTransport::TransportExIndex = -1;
+std::mutex DtlsTransport::GlobalMutex;
+
+void DtlsTransport::Init() {
+	std::lock_guard lock(GlobalMutex);
+
+	openssl::init();
+
+	if (!BioMethods) {
+		BioMethods = BIO_meth_new(BIO_TYPE_BIO, "DTLS writer");
+		if (!BioMethods)
+			throw std::runtime_error("Failed to create BIO methods for DTLS writer");
+		BIO_meth_set_create(BioMethods, BioMethodNew);
+		BIO_meth_set_destroy(BioMethods, BioMethodFree);
+		BIO_meth_set_write(BioMethods, BioMethodWrite);
+		BIO_meth_set_ctrl(BioMethods, BioMethodCtrl);
+	}
+	if (TransportExIndex < 0) {
+		TransportExIndex = SSL_get_ex_new_index(0, NULL, NULL, NULL, NULL);
+	}
+}
+
+void DtlsTransport::Cleanup() {
+	// Nothing to do
+}
+
+DtlsTransport::DtlsTransport(shared_ptr<IceTransport> lower, shared_ptr<Certificate> certificate,
+                             verifier_callback verifierCallback, state_callback stateChangeCallback)
+    : Transport(lower, std::move(stateChangeCallback)), mCertificate(certificate),
+      mVerifierCallback(std::move(verifierCallback)),
+      mIsClient(lower->role() == Description::Role::Active) {
+	PLOG_DEBUG << "Initializing DTLS transport (OpenSSL)";
+
+	try {
+		if (!(mCtx = SSL_CTX_new(DTLS_method())))
+			throw std::runtime_error("Failed to create SSL context");
+
+		openssl::check(SSL_CTX_set_cipher_list(mCtx, "ALL:!LOW:!EXP:!RC4:!MD5:@STRENGTH"),
+		               "Failed to set SSL priorities");
+
+		// RFC 8261: SCTP performs segmentation and reassembly based on the path MTU.
+		// Therefore, the DTLS layer MUST NOT use any compression algorithm.
+		// See https://tools.ietf.org/html/rfc8261#section-5
+		SSL_CTX_set_options(mCtx, SSL_OP_NO_SSLv3 | SSL_OP_NO_COMPRESSION | SSL_OP_NO_QUERY_MTU);
+		SSL_CTX_set_min_proto_version(mCtx, DTLS1_VERSION);
+		SSL_CTX_set_read_ahead(mCtx, 1);
+		SSL_CTX_set_quiet_shutdown(mCtx, 1);
+		SSL_CTX_set_info_callback(mCtx, InfoCallback);
+		SSL_CTX_set_verify(mCtx, SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
+		                   CertificateCallback);
+		SSL_CTX_set_verify_depth(mCtx, 1);
+
+		auto [x509, pkey] = mCertificate->credentials();
+		SSL_CTX_use_certificate(mCtx, x509);
+		SSL_CTX_use_PrivateKey(mCtx, pkey);
+
+		openssl::check(SSL_CTX_check_private_key(mCtx), "SSL local private key check failed");
+
+		if (!(mSsl = SSL_new(mCtx)))
+			throw std::runtime_error("Failed to create SSL instance");
+
+		SSL_set_ex_data(mSsl, TransportExIndex, this);
+
+		if (mIsClient)
+			SSL_set_connect_state(mSsl);
+		else
+			SSL_set_accept_state(mSsl);
+
+		if (!(mInBio = BIO_new(BIO_s_mem())) || !(mOutBio = BIO_new(BioMethods)))
+			throw std::runtime_error("Failed to create BIO");
+
+		BIO_set_mem_eof_return(mInBio, BIO_EOF);
+		BIO_set_data(mOutBio, this);
+		SSL_set_bio(mSsl, mInBio, mOutBio);
+
+		auto ecdh = unique_ptr<EC_KEY, decltype(&EC_KEY_free)>(
+		    EC_KEY_new_by_curve_name(NID_X9_62_prime256v1), EC_KEY_free);
+		SSL_set_options(mSsl, SSL_OP_SINGLE_ECDH_USE);
+		SSL_set_tmp_ecdh(mSsl, ecdh.get());
+
+		mRecvThread = std::thread(&DtlsTransport::runRecvLoop, this);
+		registerIncoming();
+
+	} catch (...) {
+		if (mSsl)
+			SSL_free(mSsl);
+		if (mCtx)
+			SSL_CTX_free(mCtx);
+		throw;
+	}
+}
+
+DtlsTransport::~DtlsTransport() {
+	stop();
+
+	SSL_free(mSsl);
+	SSL_CTX_free(mCtx);
+}
+
+bool DtlsTransport::stop() {
+	if (!Transport::stop())
+		return false;
+
+	PLOG_DEBUG << "Stopping DTLS recv thread";
+	mIncomingQueue.stop();
+	mRecvThread.join();
+	SSL_shutdown(mSsl);
+	return true;
+}
+
+bool DtlsTransport::send(message_ptr message) {
+	if (!message || state() != State::Connected)
+		return false;
+
+	PLOG_VERBOSE << "Send size=" << message->size();
+
+	int ret = SSL_write(mSsl, message->data(), message->size());
+	return openssl::check(mSsl, ret);
+}
+
+void DtlsTransport::incoming(message_ptr message) {
+	if (!message) {
+		mIncomingQueue.stop();
+		return;
+	}
+
+	PLOG_VERBOSE << "Incoming size=" << message->size();
+	mIncomingQueue.push(message);
+}
+
+void DtlsTransport::postHandshake() {
+	// Dummy
+}
+
+void DtlsTransport::runRecvLoop() {
+	const size_t maxMtu = 4096;
+	try {
+		changeState(State::Connecting);
+		SSL_set_mtu(mSsl, 1280 - 40 - 8); // min MTU over UDP/IPv6
+
+		// Initiate the handshake
+		int ret = SSL_do_handshake(mSsl);
+		openssl::check(mSsl, ret, "Handshake failed");
+
+		const size_t bufferSize = maxMtu;
+		byte buffer[bufferSize];
+		while (true) {
+			// Process pending messages
+			while (!mIncomingQueue.empty()) {
+				auto message = *mIncomingQueue.pop();
+				BIO_write(mInBio, message->data(), message->size());
+
+				if (state() == State::Connecting) {
+					// Continue the handshake
+					int ret = SSL_do_handshake(mSsl);
+					if (!openssl::check(mSsl, ret, "Handshake failed"))
+						break;
+
+					if (SSL_is_init_finished(mSsl)) {
+						// RFC 8261: DTLS MUST support sending messages larger than the current path
+						// MTU See https://tools.ietf.org/html/rfc8261#section-5
+						SSL_set_mtu(mSsl, maxMtu + 1);
+
+						PLOG_INFO << "DTLS handshake finished";
+						changeState(State::Connected);
+						postHandshake();
+					}
+				} else {
+					int ret = SSL_read(mSsl, buffer, bufferSize);
+					if (!openssl::check(mSsl, ret))
+						break;
+
+					if (ret > 0)
+						recv(make_message(buffer, buffer + ret));
+				}
+			}
+
+			// No more messages pending, retransmit and rearm timeout if connecting
+			std::optional<milliseconds> duration;
+			if (state() == State::Connecting) {
+				// Warning: This function breaks the usual return value convention
+				int ret = DTLSv1_handle_timeout(mSsl);
+				if (ret < 0) {
+					throw std::runtime_error("Handshake timeout"); // write BIO can't fail
+				} else if (ret > 0) {
+					LOG_VERBOSE << "OpenSSL did DTLS retransmit";
+				}
+
+				struct timeval timeout = {};
+				if (state() == State::Connecting && DTLSv1_get_timeout(mSsl, &timeout)) {
+					duration = milliseconds(timeout.tv_sec * 1000 + timeout.tv_usec / 1000);
+					// Also handle handshake timeout manually because OpenSSL actually doesn't...
+					// OpenSSL backs off exponentially in base 2 starting from the recommended 1s
+					// so this allows for 5 retransmissions and fails after roughly 30s.
+					if (duration > 30s) {
+						throw std::runtime_error("Handshake timeout");
+					} else {
+						LOG_VERBOSE << "OpenSSL DTLS retransmit timeout is " << duration->count()
+						            << "ms";
+					}
+				}
+			}
+
+			if (!mIncomingQueue.wait(duration))
+				break; // queue is stopped
+		}
+	} catch (const std::exception &e) {
+		PLOG_ERROR << "DTLS recv: " << e.what();
+	}
+
+	if (state() == State::Connected) {
+		PLOG_INFO << "DTLS closed";
+		changeState(State::Disconnected);
+		recv(nullptr);
+	} else {
+		PLOG_ERROR << "DTLS handshake failed";
+		changeState(State::Failed);
+	}
+}
+
+int DtlsTransport::CertificateCallback(int preverify_ok, X509_STORE_CTX *ctx) {
+	SSL *ssl =
+	    static_cast<SSL *>(X509_STORE_CTX_get_ex_data(ctx, SSL_get_ex_data_X509_STORE_CTX_idx()));
+	DtlsTransport *t =
+	    static_cast<DtlsTransport *>(SSL_get_ex_data(ssl, DtlsTransport::TransportExIndex));
+
+	X509 *crt = X509_STORE_CTX_get_current_cert(ctx);
+	string fingerprint = make_fingerprint(crt);
+
+	return t->mVerifierCallback(fingerprint) ? 1 : 0;
+}
+
+void DtlsTransport::InfoCallback(const SSL *ssl, int where, int ret) {
+	DtlsTransport *t =
+	    static_cast<DtlsTransport *>(SSL_get_ex_data(ssl, DtlsTransport::TransportExIndex));
+
+	if (where & SSL_CB_ALERT) {
+		if (ret != 256) { // Close Notify
+			PLOG_ERROR << "DTLS alert: " << SSL_alert_desc_string_long(ret);
+		}
+		t->mIncomingQueue.stop(); // Close the connection
+	}
+}
+
+int DtlsTransport::BioMethodNew(BIO *bio) {
+	BIO_set_init(bio, 1);
+	BIO_set_data(bio, NULL);
+	BIO_set_shutdown(bio, 0);
+	return 1;
+}
+
+int DtlsTransport::BioMethodFree(BIO *bio) {
+	if (!bio)
+		return 0;
+	BIO_set_data(bio, NULL);
+	return 1;
+}
+
+int DtlsTransport::BioMethodWrite(BIO *bio, const char *in, int inl) {
+	if (inl <= 0)
+		return inl;
+	auto transport = reinterpret_cast<DtlsTransport *>(BIO_get_data(bio));
+	if (!transport)
+		return -1;
+	auto b = reinterpret_cast<const byte *>(in);
+	transport->outgoing(make_message(b, b + inl));
+	return inl; // can't fail
+}
+
+long DtlsTransport::BioMethodCtrl(BIO *bio, int cmd, long num, void *ptr) {
+	switch (cmd) {
+	case BIO_CTRL_FLUSH:
+		return 1;
+	case BIO_CTRL_DGRAM_QUERY_MTU:
+		return 0; // SSL_OP_NO_QUERY_MTU must be set
+	case BIO_CTRL_WPENDING:
+	case BIO_CTRL_PENDING:
+		return 0;
+	default:
+		break;
+	}
+	return 0;
+}
+
+#endif
+
 } // namespace rtc
+

src/dtlstransport.hpp

@@ -23,53 +23,69 @@
 #include "include.hpp"
 #include "peerconnection.hpp"
 #include "queue.hpp"
+#include "tls.hpp"
 #include "transport.hpp"
 
 #include <atomic>
 #include <functional>
 #include <memory>
+#include <mutex>
 #include <thread>
 
-#include <gnutls/gnutls.h>
-
 namespace rtc {
 
 class IceTransport;
 
 class DtlsTransport : public Transport {
 public:
-	enum class State { Disconnected, Connecting, Connected, Failed };
+	static void Init();
+	static void Cleanup();
 
 	using verifier_callback = std::function<bool(const std::string &fingerprint)>;
-	using state_callback = std::function<void(State state)>;
 
-	DtlsTransport(std::shared_ptr<IceTransport> lower, std::shared_ptr<Certificate> certificate,
+	DtlsTransport(std::shared_ptr<IceTransport> lower, certificate_ptr certificate,
 	              verifier_callback verifierCallback, state_callback stateChangeCallback);
 	~DtlsTransport();
 
-	State state() const;
+	virtual bool stop() override;
+	virtual bool send(message_ptr message) override; // false if dropped
 
-	bool send(message_ptr message);
+protected:
-
+	virtual void incoming(message_ptr message) override;
-private:
+	virtual void postHandshake();
-	void incoming(message_ptr message);
-	void changeState(State state);
 	void runRecvLoop();
 
-	const std::shared_ptr<Certificate> mCertificate;
+	const certificate_ptr mCertificate;
+	const verifier_callback mVerifierCallback;
+	const bool mIsClient;
 
-	gnutls_session_t mSession;
 	Queue<message_ptr> mIncomingQueue;
-	std::atomic<State> mState;
 	std::thread mRecvThread;
 
-	verifier_callback mVerifierCallback;
+#if USE_GNUTLS
-	state_callback mStateChangeCallback;
+	gnutls_session_t mSession;
 
 	static int CertificateCallback(gnutls_session_t session);
 	static ssize_t WriteCallback(gnutls_transport_ptr_t ptr, const void *data, size_t len);
 	static ssize_t ReadCallback(gnutls_transport_ptr_t ptr, void *data, size_t maxlen);
 	static int TimeoutCallback(gnutls_transport_ptr_t ptr, unsigned int ms);
+#else
+	SSL_CTX *mCtx = NULL;
+	SSL *mSsl = NULL;
+	BIO *mInBio, *mOutBio;
+
+	static BIO_METHOD *BioMethods;
+	static int TransportExIndex;
+	static std::mutex GlobalMutex;
+
+	static int CertificateCallback(int preverify_ok, X509_STORE_CTX *ctx);
+	static void InfoCallback(const SSL *ssl, int where, int ret);
+
+	static int BioMethodNew(BIO *bio);
+	static int BioMethodFree(BIO *bio);
+	static int BioMethodWrite(BIO *bio, const char *in, int inl);
+	static long BioMethodCtrl(BIO *bio, int cmd, long num, void *ptr);
+#endif
 };
 
 } // namespace rtc

src/icetransport.cpp

@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2019 Paul-Louis Ageneau
+ * Copyright (c) 2019-2020 Paul-Louis Ageneau
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -17,40 +17,283 @@
  */
 
 #include "icetransport.hpp"
+#include "configuration.hpp"
+#include "transport.hpp"
 
-#include <netdb.h>
-#include <netinet/in.h>
-#include <sys/socket.h>
-#include <sys/types.h>
-
-#include <chrono>
 #include <iostream>
 #include <random>
 #include <sstream>
 
-namespace rtc {
+#ifdef _WIN32
+#include <winsock2.h>
+#include <ws2tcpip.h>
+#else
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <sys/socket.h>
+#endif
+
+#include <sys/types.h>
+
+using namespace std::chrono_literals;
 
 using std::shared_ptr;
 using std::weak_ptr;
 
-IceTransport::IceTransport(const Configuration &config, Description::Role role,
+#if USE_JUICE
-                           candidate_callback candidateCallback,
-                           state_callback stateChangeCallback,
-                           gathering_state_callback gatheringStateChangeCallback)
-    : mRole(role), mMid("0"), mState(State::Disconnected), mGatheringState(GatheringState::New),
-      mNiceAgent(nullptr, nullptr), mMainLoop(nullptr, nullptr),
-      mCandidateCallback(std::move(candidateCallback)),
-      mStateChangeCallback(std::move(stateChangeCallback)),
-      mGatheringStateChangeCallback(std::move(gatheringStateChangeCallback)) {
 
-	auto logLevelFlags = GLogLevelFlags(G_LOG_LEVEL_MASK | G_LOG_FLAG_FATAL | G_LOG_FLAG_RECURSION);
+namespace rtc {
-	g_log_set_handler(nullptr, logLevelFlags, LogCallback, this);
+
-	nice_debug_enable(false);
+IceTransport::IceTransport(const Configuration &config, Description::Role role,
+                           candidate_callback candidateCallback, state_callback stateChangeCallback,
+                           gathering_state_callback gatheringStateChangeCallback)
+    : Transport(nullptr, std::move(stateChangeCallback)), mRole(role), mMid("0"),
+      mGatheringState(GatheringState::New), mCandidateCallback(std::move(candidateCallback)),
+      mGatheringStateChangeCallback(std::move(gatheringStateChangeCallback)),
+      mAgent(nullptr, nullptr) {
+
+	PLOG_DEBUG << "Initializing ICE transport (libjuice)";
+	if (config.enableIceTcp) {
+		PLOG_WARNING << "ICE-TCP is not supported with libjuice";
+	}
+	juice_set_log_handler(IceTransport::LogCallback);
+	juice_set_log_level(JUICE_LOG_LEVEL_VERBOSE);
+
+	juice_config_t jconfig = {};
+	jconfig.cb_state_changed = IceTransport::StateChangeCallback;
+	jconfig.cb_candidate = IceTransport::CandidateCallback;
+	jconfig.cb_gathering_done = IceTransport::GatheringDoneCallback;
+	jconfig.cb_recv = IceTransport::RecvCallback;
+	jconfig.user_ptr = this;
+
+	// Randomize servers order
+	std::vector<IceServer> servers = config.iceServers;
+	unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
+	std::shuffle(servers.begin(), servers.end(), std::default_random_engine(seed));
+
+	// Pick a STUN server (TURN support is not implemented in libjuice yet)
+	for (auto &server : servers) {
+		if (!server.hostname.empty() && server.type == IceServer::Type::Stun) {
+			if (server.service.empty())
+				server.service = "3478"; // STUN UDP port
+			PLOG_DEBUG << "Using STUN server \"" << server.hostname << ":" << server.service
+			           << "\"";
+			mStunHostname = server.hostname;
+			mStunService = server.service;
+			jconfig.stun_server_host = mStunHostname.c_str();
+			jconfig.stun_server_port = std::stoul(mStunService);
+			break;
+		}
+	}
+
+	// Port range
+	if (config.portRangeBegin > 1024 ||
+	    (config.portRangeEnd != 0 && config.portRangeEnd != 65535)) {
+		jconfig.local_port_range_begin = config.portRangeBegin;
+		jconfig.local_port_range_end = config.portRangeEnd;
+	}
+
+	// Create agent
+	mAgent = decltype(mAgent)(juice_create(&jconfig), juice_destroy);
+	if (!mAgent)
+		throw std::runtime_error("Failed to create the ICE agent");
+}
+
+IceTransport::~IceTransport() {
+	stop();
+	mAgent.reset();
+}
+
+bool IceTransport::stop() {
+	return Transport::stop();
+}
+
+Description::Role IceTransport::role() const { return mRole; }
+
+Description IceTransport::getLocalDescription(Description::Type type) const {
+	char sdp[JUICE_MAX_SDP_STRING_LEN];
+	if (juice_get_local_description(mAgent.get(), sdp, JUICE_MAX_SDP_STRING_LEN) < 0)
+		throw std::runtime_error("Failed to generate local SDP");
+
+	return Description(string(sdp), type, mRole);
+}
+
+void IceTransport::setRemoteDescription(const Description &description) {
+	mRole = description.role() == Description::Role::Active ? Description::Role::Passive
+	                                                        : Description::Role::Active;
+	mMid = description.dataMid();
+	if (juice_set_remote_description(mAgent.get(), string(description).c_str()) < 0)
+		throw std::runtime_error("Failed to parse remote SDP");
+}
+
+bool IceTransport::addRemoteCandidate(const Candidate &candidate) {
+	// Don't try to pass unresolved candidates for more safety
+	if (!candidate.isResolved())
+		return false;
+
+	return juice_add_remote_candidate(mAgent.get(), string(candidate).c_str()) >= 0;
+}
+
+void IceTransport::gatherLocalCandidates() {
+	// Change state now as candidates calls can be synchronous
+	changeGatheringState(GatheringState::InProgress);
+
+	if (juice_gather_candidates(mAgent.get()) < 0) {
+		throw std::runtime_error("Failed to gather local ICE candidates");
+	}
+}
+
+std::optional<string> IceTransport::getLocalAddress() const {
+	char str[JUICE_MAX_ADDRESS_STRING_LEN];
+	if (juice_get_selected_addresses(mAgent.get(), str, JUICE_MAX_ADDRESS_STRING_LEN, NULL, 0) ==
+	    0) {
+		return std::make_optional(string(str));
+	}
+	return nullopt;
+}
+std::optional<string> IceTransport::getRemoteAddress() const {
+	char str[JUICE_MAX_ADDRESS_STRING_LEN];
+	if (juice_get_selected_addresses(mAgent.get(), NULL, 0, str, JUICE_MAX_ADDRESS_STRING_LEN) ==
+	    0) {
+		return std::make_optional(string(str));
+	}
+	return nullopt;
+}
+
+bool IceTransport::send(message_ptr message) {
+	auto s = state();
+	if (!message || (s != State::Connected && s != State::Completed))
+		return false;
+
+	PLOG_VERBOSE << "Send size=" << message->size();
+	return outgoing(message);
+}
+
+bool IceTransport::outgoing(message_ptr message) {
+	return juice_send(mAgent.get(), reinterpret_cast<const char *>(message->data()),
+	                  message->size()) >= 0;
+}
+
+void IceTransport::changeGatheringState(GatheringState state) {
+	if (mGatheringState.exchange(state) != state)
+		mGatheringStateChangeCallback(mGatheringState);
+}
+
+void IceTransport::processStateChange(unsigned int state) {
+	switch (state) {
+	case JUICE_STATE_DISCONNECTED:
+		changeState(State::Disconnected);
+		break;
+	case JUICE_STATE_CONNECTING:
+		changeState(State::Connecting);
+		break;
+	case JUICE_STATE_CONNECTED:
+		changeState(State::Connected);
+		break;
+	case JUICE_STATE_COMPLETED:
+		changeState(State::Completed);
+		break;
+	case JUICE_STATE_FAILED:
+		changeState(State::Failed);
+		break;
+	};
+}
+
+void IceTransport::processCandidate(const string &candidate) {
+	mCandidateCallback(Candidate(candidate, mMid));
+}
+
+void IceTransport::processGatheringDone() { changeGatheringState(GatheringState::Complete); }
+
+void IceTransport::StateChangeCallback(juice_agent_t *agent, juice_state_t state, void *user_ptr) {
+	auto iceTransport = static_cast<rtc::IceTransport *>(user_ptr);
+	try {
+		iceTransport->processStateChange(static_cast<unsigned int>(state));
+	} catch (const std::exception &e) {
+		PLOG_WARNING << e.what();
+	}
+}
+
+void IceTransport::CandidateCallback(juice_agent_t *agent, const char *sdp, void *user_ptr) {
+	auto iceTransport = static_cast<rtc::IceTransport *>(user_ptr);
+	try {
+		iceTransport->processCandidate(sdp);
+	} catch (const std::exception &e) {
+		PLOG_WARNING << e.what();
+	}
+}
+
+void IceTransport::GatheringDoneCallback(juice_agent_t *agent, void *user_ptr) {
+	auto iceTransport = static_cast<rtc::IceTransport *>(user_ptr);
+	try {
+		iceTransport->processGatheringDone();
+	} catch (const std::exception &e) {
+		PLOG_WARNING << e.what();
+	}
+}
+
+void IceTransport::RecvCallback(juice_agent_t *agent, const char *data, size_t size,
+                                void *user_ptr) {
+	auto iceTransport = static_cast<rtc::IceTransport *>(user_ptr);
+	try {
+		PLOG_VERBOSE << "Incoming size=" << size;
+		auto b = reinterpret_cast<const byte *>(data);
+		iceTransport->incoming(make_message(b, b + size));
+	} catch (const std::exception &e) {
+		PLOG_WARNING << e.what();
+	}
+}
+
+void IceTransport::LogCallback(juice_log_level_t level, const char *message) {
+	plog::Severity severity;
+	switch (level) {
+	case JUICE_LOG_LEVEL_FATAL:
+		severity = plog::fatal;
+		break;
+	case JUICE_LOG_LEVEL_ERROR:
+		severity = plog::error;
+		break;
+	case JUICE_LOG_LEVEL_WARN:
+		severity = plog::warning;
+		break;
+	case JUICE_LOG_LEVEL_INFO:
+		severity = plog::info;
+		break;
+	default:
+		severity = plog::verbose; // libjuice debug as verbose
+		break;
+	}
+	PLOG(severity) << "juice: " << message;
+}
+
+} // namespace rtc
+
+#else // USE_JUICE == 0
+
+namespace rtc {
+
+IceTransport::IceTransport(const Configuration &config, Description::Role role,
+                           candidate_callback candidateCallback, state_callback stateChangeCallback,
+                           gathering_state_callback gatheringStateChangeCallback)
+    : Transport(nullptr, std::move(stateChangeCallback)), mRole(role), mMid("0"),
+      mGatheringState(GatheringState::New), mCandidateCallback(std::move(candidateCallback)),
+      mGatheringStateChangeCallback(std::move(gatheringStateChangeCallback)),
+      mNiceAgent(nullptr, nullptr), mMainLoop(nullptr, nullptr) {
+
+	PLOG_DEBUG << "Initializing ICE transport (libnice)";
+
+	g_log_set_handler("libnice", G_LOG_LEVEL_MASK, LogCallback, this);
+
+	IF_PLOG(plog::verbose) {
+		nice_debug_enable(false); // do not output STUN debug messages
+	}
 
 	mMainLoop = decltype(mMainLoop)(g_main_loop_new(nullptr, FALSE), g_main_loop_unref);
 	if (!mMainLoop)
 		std::runtime_error("Failed to create the main loop");
 
+	// RFC 5245 was obsoleted by RFC 8445 but this should be OK.
 	mNiceAgent = decltype(mNiceAgent)(
 	    nice_agent_new(g_main_loop_get_context(mMainLoop.get()), NICE_COMPATIBILITY_RFC5245),
 	    g_object_unref);
@@ -59,19 +302,51 @@ IceTransport::IceTransport(const Configuration &config, Description::Role role,
 		throw std::runtime_error("Failed to create the nice agent");
 
 	mMainLoopThread = std::thread(g_main_loop_run, mMainLoop.get());
-	g_object_set(G_OBJECT(mNiceAgent.get()), "upnp", FALSE, nullptr);
-	g_object_set(G_OBJECT(mNiceAgent.get()), "controlling-mode", FALSE, nullptr);
-	g_object_set(G_OBJECT(mNiceAgent.get()), "ice-udp", TRUE, nullptr);
-	g_object_set(G_OBJECT(mNiceAgent.get()), "ice-tcp", FALSE, nullptr);
 
+	mStreamId = nice_agent_add_stream(mNiceAgent.get(), 1);
+	if (!mStreamId)
+		throw std::runtime_error("Failed to add a stream");
+
+	g_object_set(G_OBJECT(mNiceAgent.get()), "controlling-mode", TRUE, nullptr); // decided later
+	g_object_set(G_OBJECT(mNiceAgent.get()), "ice-udp", TRUE, nullptr);
+	g_object_set(G_OBJECT(mNiceAgent.get()), "ice-tcp", config.enableIceTcp ? TRUE : FALSE,
+	             nullptr);
+
+	// RFC 8445: Agents MUST NOT use an RTO value smaller than 500 ms.
+	g_object_set(G_OBJECT(mNiceAgent.get()), "stun-initial-timeout", 500, nullptr);
+	g_object_set(G_OBJECT(mNiceAgent.get()), "stun-max-retransmissions", 3, nullptr);
+
+	// RFC 8445: ICE agents SHOULD use a default Ta value, 50 ms, but MAY use another value based on
+	// the characteristics of the associated data.
+	g_object_set(G_OBJECT(mNiceAgent.get()), "stun-pacing-timer", 25, nullptr);
+
+	g_object_set(G_OBJECT(mNiceAgent.get()), "upnp", FALSE, nullptr);
+	g_object_set(G_OBJECT(mNiceAgent.get()), "upnp-timeout", 200, nullptr);
+
+	// Proxy
+	if (config.proxyServer.has_value()) {
+		ProxyServer proxyServer = config.proxyServer.value();
+		g_object_set(G_OBJECT(mNiceAgent.get()), "proxy-type", proxyServer.type, nullptr);
+		g_object_set(G_OBJECT(mNiceAgent.get()), "proxy-ip", proxyServer.ip.c_str(), nullptr);
+		g_object_set(G_OBJECT(mNiceAgent.get()), "proxy-port", proxyServer.port, nullptr);
+		g_object_set(G_OBJECT(mNiceAgent.get()), "proxy-username", proxyServer.username.c_str(),
+		             nullptr);
+		g_object_set(G_OBJECT(mNiceAgent.get()), "proxy-password", proxyServer.password.c_str(),
+		             nullptr);
+	}
+
+	// Randomize order
 	std::vector<IceServer> servers = config.iceServers;
 	unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
 	std::shuffle(servers.begin(), servers.end(), std::default_random_engine(seed));
 
+	// Add one STUN server
 	bool success = false;
 	for (auto &server : servers) {
 		if (server.hostname.empty())
 			continue;
+		if (server.type != IceServer::Type::Stun)
+			continue;
 		if (server.service.empty())
 			server.service = "3478"; // STUN UDP port
 
@@ -91,6 +366,8 @@ IceTransport::IceTransport(const Configuration &config, Description::Role role,
 				if (getnameinfo(p->ai_addr, p->ai_addrlen, nodebuffer, MAX_NUMERICNODE_LEN,
 				                servbuffer, MAX_NUMERICNODE_LEN,
 				                NI_NUMERICHOST | NI_NUMERICSERV) == 0) {
+					PLOG_DEBUG << "Using STUN server \"" << server.hostname << ":" << server.service
+					           << "\"";
 					g_object_set(G_OBJECT(mNiceAgent.get()), "stun-server", nodebuffer, nullptr);
 					g_object_set(G_OBJECT(mNiceAgent.get()), "stun-server-port",
 					             std::stoul(servbuffer), nullptr);
@@ -105,6 +382,56 @@ IceTransport::IceTransport(const Configuration &config, Description::Role role,
 			break;
 	}
 
+	// Add TURN servers
+	for (auto &server : servers) {
+		if (server.hostname.empty())
+			continue;
+		if (server.type != IceServer::Type::Turn)
+			continue;
+		if (server.service.empty())
+			server.service = server.relayType == IceServer::RelayType::TurnTls ? "5349" : "3478";
+
+		struct addrinfo hints = {};
+		hints.ai_family = AF_UNSPEC;
+		hints.ai_socktype =
+		    server.relayType == IceServer::RelayType::TurnUdp ? SOCK_DGRAM : SOCK_STREAM;
+		hints.ai_protocol =
+		    server.relayType == IceServer::RelayType::TurnUdp ? IPPROTO_UDP : IPPROTO_TCP;
+		hints.ai_flags = AI_ADDRCONFIG;
+		struct addrinfo *result = nullptr;
+		if (getaddrinfo(server.hostname.c_str(), server.service.c_str(), &hints, &result) != 0)
+			continue;
+
+		for (auto p = result; p; p = p->ai_next) {
+			if (p->ai_family == AF_INET || p->ai_family == AF_INET6) {
+				char nodebuffer[MAX_NUMERICNODE_LEN];
+				char servbuffer[MAX_NUMERICSERV_LEN];
+				if (getnameinfo(p->ai_addr, p->ai_addrlen, nodebuffer, MAX_NUMERICNODE_LEN,
+				                servbuffer, MAX_NUMERICNODE_LEN,
+				                NI_NUMERICHOST | NI_NUMERICSERV) == 0) {
+
+					NiceRelayType niceRelayType;
+					switch (server.relayType) {
+					case IceServer::RelayType::TurnTcp:
+						niceRelayType = NICE_RELAY_TYPE_TURN_TCP;
+						break;
+					case IceServer::RelayType::TurnTls:
+						niceRelayType = NICE_RELAY_TYPE_TURN_TLS;
+						break;
+					default:
+						niceRelayType = NICE_RELAY_TYPE_TURN_UDP;
+						break;
+					}
+					nice_agent_set_relay_info(mNiceAgent.get(), mStreamId, 1, nodebuffer,
+					                          std::stoul(servbuffer), server.username.c_str(),
+					                          server.password.c_str(), niceRelayType);
+				}
+			}
+		}
+
+		freeaddrinfo(result);
+	}
+
 	g_signal_connect(G_OBJECT(mNiceAgent.get()), "component-state-changed",
 	                 G_CALLBACK(StateChangeCallback), this);
 	g_signal_connect(G_OBJECT(mNiceAgent.get()), "new-candidate-full",
@@ -112,10 +439,6 @@ IceTransport::IceTransport(const Configuration &config, Description::Role role,
 	g_signal_connect(G_OBJECT(mNiceAgent.get()), "candidate-gathering-done",
 	                 G_CALLBACK(GatheringDoneCallback), this);
 
-	mStreamId = nice_agent_add_stream(mNiceAgent.get(), 1);
-	if (!mStreamId)
-		throw std::runtime_error("Failed to add a stream");
-
 	nice_agent_set_stream_name(mNiceAgent.get(), mStreamId, "application");
 	nice_agent_set_port_range(mNiceAgent.get(), mStreamId, 1, config.portRangeBegin,
 	                          config.portRangeEnd);
@@ -124,17 +447,34 @@ IceTransport::IceTransport(const Configuration &config, Description::Role role,
 	                       RecvCallback, this);
 }
 
-IceTransport::~IceTransport() {
+IceTransport::~IceTransport() { stop(); }
+
+bool IceTransport::stop() {
+	if (mTimeoutId) {
+		g_source_remove(mTimeoutId);
+		mTimeoutId = 0;
+	}
+
+	if (!Transport::stop())
+		return false;
+
+	PLOG_DEBUG << "Stopping ICE thread";
+	nice_agent_attach_recv(mNiceAgent.get(), mStreamId, 1, g_main_loop_get_context(mMainLoop.get()),
+	                       NULL, NULL);
+	nice_agent_remove_stream(mNiceAgent.get(), mStreamId);
 	g_main_loop_quit(mMainLoop.get());
-	if (mMainLoopThread.joinable())
 	mMainLoopThread.join();
+	return true;
 }
 
 Description::Role IceTransport::role() const { return mRole; }
 
-IceTransport::State IceTransport::state() const { return mState; }
-
 Description IceTransport::getLocalDescription(Description::Type type) const {
+	// RFC 8445: The initiating agent that started the ICE processing MUST take the controlling
+	// role, and the other MUST take the controlled role.
+	g_object_set(G_OBJECT(mNiceAgent.get()), "controlling-mode",
+	             type == Description::Type::Offer ? TRUE : FALSE, nullptr);
+
 	std::unique_ptr<gchar[], void (*)(void *)> sdp(nice_agent_generate_local_sdp(mNiceAgent.get()),
 	                                               g_free);
 	return Description(string(sdp.get()), type, mRole);
@@ -143,22 +483,19 @@ Description IceTransport::getLocalDescription(Description::Type type) const {
 void IceTransport::setRemoteDescription(const Description &description) {
 	mRole = description.role() == Description::Role::Active ? Description::Role::Passive
 	                                                        : Description::Role::Active;
-	mMid = description.mid();
+	mMid = description.dataMid();
+	mTrickleTimeout = !description.ended() ? 30s : 0s;
 
-	if (nice_agent_parse_remote_sdp(mNiceAgent.get(), string(description).c_str()))
+	// Warning: libnice expects "\n" as end of line
+	if (nice_agent_parse_remote_sdp(mNiceAgent.get(), description.generateSdp("\n").c_str()) < 0)
 		throw std::runtime_error("Failed to parse remote SDP");
 }
 
-void IceTransport::gatherLocalCandidates() {
-	// Change state now as candidates calls can be synchronous
-	changeGatheringState(GatheringState::InProgress);
-
-	if (!nice_agent_gather_candidates(mNiceAgent.get(), mStreamId)) {
-		throw std::runtime_error("Failed to gather local ICE candidates");
-	}
-}
-
 bool IceTransport::addRemoteCandidate(const Candidate &candidate) {
+	// Don't try to pass unresolved candidates to libnice for more safety
+	if (!candidate.isResolved())
+		return false;
+
 	// Warning: the candidate string must start with "a=candidate:" and it must not end with a
 	// newline, else libnice will reject it.
 	string sdp(candidate);
@@ -174,44 +511,103 @@ bool IceTransport::addRemoteCandidate(const Candidate &candidate) {
 	return ret > 0;
 }
 
+void IceTransport::gatherLocalCandidates() {
+	// Change state now as candidates calls can be synchronous
+	changeGatheringState(GatheringState::InProgress);
+
+	if (!nice_agent_gather_candidates(mNiceAgent.get(), mStreamId)) {
+		throw std::runtime_error("Failed to gather local ICE candidates");
+	}
+}
+
+std::optional<string> IceTransport::getLocalAddress() const {
+	NiceCandidate *local = nullptr;
+	NiceCandidate *remote = nullptr;
+	if (nice_agent_get_selected_pair(mNiceAgent.get(), mStreamId, 1, &local, &remote)) {
+		return std::make_optional(AddressToString(local->addr));
+	}
+	return nullopt;
+}
+
+std::optional<string> IceTransport::getRemoteAddress() const {
+	NiceCandidate *local = nullptr;
+	NiceCandidate *remote = nullptr;
+	if (nice_agent_get_selected_pair(mNiceAgent.get(), mStreamId, 1, &local, &remote)) {
+		return std::make_optional(AddressToString(remote->addr));
+	}
+	return nullopt;
+}
+
 bool IceTransport::send(message_ptr message) {
-	if (!message || !mStreamId)
+	auto s = state();
+	if (!message || (s != State::Connected && s != State::Completed))
 		return false;
 
-	outgoing(message);
+	PLOG_VERBOSE << "Send size=" << message->size();
-	return true;
+	return outgoing(message);
 }
 
-void IceTransport::incoming(message_ptr message) { recv(message); }
+bool IceTransport::outgoing(message_ptr message) {
-
+	return nice_agent_send(mNiceAgent.get(), mStreamId, 1, message->size(),
-void IceTransport::incoming(const byte *data, int size) {
+	                       reinterpret_cast<const char *>(message->data())) >= 0;
-	incoming(make_message(data, data + size));
-}
-
-void IceTransport::outgoing(message_ptr message) {
-	nice_agent_send(mNiceAgent.get(), mStreamId, 1, message->size(),
-	                reinterpret_cast<const char *>(message->data()));
-}
-
-void IceTransport::changeState(State state) {
-	mState = state;
-	mStateChangeCallback(mState);
 }
 
 void IceTransport::changeGatheringState(GatheringState state) {
-	mGatheringState = state;
+	if (mGatheringState.exchange(state) != state)
 		mGatheringStateChangeCallback(mGatheringState);
 }
 
+void IceTransport::processTimeout() {
+	PLOG_WARNING << "ICE timeout";
+	mTimeoutId = 0;
+	changeState(State::Failed);
+}
+
 void IceTransport::processCandidate(const string &candidate) {
 	mCandidateCallback(Candidate(candidate, mMid));
 }
 
 void IceTransport::processGatheringDone() { changeGatheringState(GatheringState::Complete); }
 
-void IceTransport::processStateChange(uint32_t state) {
+void IceTransport::processStateChange(unsigned int state) {
-	if (state != NICE_COMPONENT_STATE_GATHERING)
+	if (state == NICE_COMPONENT_STATE_FAILED && mTrickleTimeout.count() > 0) {
-		changeState(static_cast<State>(state));
+		if (mTimeoutId)
+			g_source_remove(mTimeoutId);
+		mTimeoutId = g_timeout_add(mTrickleTimeout.count() /* ms */, TimeoutCallback, this);
+		return;
+	}
+
+	if (state == NICE_COMPONENT_STATE_CONNECTED && mTimeoutId) {
+		g_source_remove(mTimeoutId);
+		mTimeoutId = 0;
+	}
+
+	switch (state) {
+	case NICE_COMPONENT_STATE_DISCONNECTED:
+		changeState(State::Disconnected);
+		break;
+	case NICE_COMPONENT_STATE_CONNECTING:
+		changeState(State::Connecting);
+		break;
+	case NICE_COMPONENT_STATE_CONNECTED:
+		changeState(State::Connected);
+		break;
+	case NICE_COMPONENT_STATE_READY:
+		changeState(State::Completed);
+		break;
+	case NICE_COMPONENT_STATE_FAILED:
+		changeState(State::Failed);
+		break;
+	};
+}
+
+string IceTransport::AddressToString(const NiceAddress &addr) {
+	char buffer[NICE_ADDRESS_STRING_LEN];
+	nice_address_to_string(&addr, buffer);
+	unsigned int port = nice_address_get_port(&addr);
+	std::ostringstream ss;
+	ss << buffer << ":" << port;
+	return ss.str();
 }
 
 void IceTransport::CandidateCallback(NiceAgent *agent, NiceCandidate *candidate,
@@ -221,7 +617,7 @@ void IceTransport::CandidateCallback(NiceAgent *agent, NiceCandidate *candidate,
 	try {
 		iceTransport->processCandidate(cand);
 	} catch (const std::exception &e) {
-		std::cerr << "ICE candidate: " << e.what() << std::endl;
+		PLOG_WARNING << e.what();
 	}
 	g_free(cand);
 }
@@ -231,7 +627,7 @@ void IceTransport::GatheringDoneCallback(NiceAgent *agent, guint streamId, gpoin
 	try {
 		iceTransport->processGatheringDone();
 	} catch (const std::exception &e) {
-		std::cerr << "ICE gathering done: " << e.what() << std::endl;
+		PLOG_WARNING << e.what();
 	}
 }
 
@@ -241,7 +637,7 @@ void IceTransport::StateChangeCallback(NiceAgent *agent, guint streamId, guint c
 	try {
 		iceTransport->processStateChange(state);
 	} catch (const std::exception &e) {
-		std::cerr << "ICE change state: " << e.what() << std::endl;
+		PLOG_WARNING << e.what();
 	}
 }
 
@@ -249,15 +645,96 @@ void IceTransport::RecvCallback(NiceAgent *agent, guint streamId, guint componen
                                 gchar *buf, gpointer userData) {
 	auto iceTransport = static_cast<rtc::IceTransport *>(userData);
 	try {
-		iceTransport->incoming(reinterpret_cast<byte *>(buf), len);
+		PLOG_VERBOSE << "Incoming size=" << len;
+		auto b = reinterpret_cast<byte *>(buf);
+		iceTransport->incoming(make_message(b, b + len));
 	} catch (const std::exception &e) {
-		std::cerr << "ICE incoming: " << e.what() << std::endl;
+		PLOG_WARNING << e.what();
 	}
 }
 
+gboolean IceTransport::TimeoutCallback(gpointer userData) {
+	auto iceTransport = static_cast<rtc::IceTransport *>(userData);
+	try {
+		iceTransport->processTimeout();
+	} catch (const std::exception &e) {
+		PLOG_WARNING << e.what();
+	}
+	return FALSE;
+}
+
 void IceTransport::LogCallback(const gchar *logDomain, GLogLevelFlags logLevel,
                                const gchar *message, gpointer userData) {
-	std::cout << message << std::endl;
+	plog::Severity severity;
+	unsigned int flags = logLevel & G_LOG_LEVEL_MASK;
+	if (flags & G_LOG_LEVEL_ERROR)
+		severity = plog::fatal;
+	else if (flags & G_LOG_LEVEL_CRITICAL)
+		severity = plog::error;
+	else if (flags & G_LOG_LEVEL_WARNING)
+		severity = plog::warning;
+	else if (flags & G_LOG_LEVEL_MESSAGE)
+		severity = plog::info;
+	else if (flags & G_LOG_LEVEL_INFO)
+		severity = plog::info;
+	else
+		severity = plog::verbose; // libnice debug as verbose
+
+	PLOG(severity) << "nice: " << message;
+}
+
+bool IceTransport::getSelectedCandidatePair(CandidateInfo *localInfo, CandidateInfo *remoteInfo) {
+	NiceCandidate *local, *remote;
+	gboolean result = nice_agent_get_selected_pair(mNiceAgent.get(), mStreamId, 1, &local, &remote);
+
+	if (!result)
+		return false;
+
+	char ipaddr[INET6_ADDRSTRLEN];
+	nice_address_to_string(&local->addr, ipaddr);
+	localInfo->address = std::string(ipaddr);
+	localInfo->port = nice_address_get_port(&local->addr);
+	localInfo->type = IceTransport::NiceTypeToCandidateType(local->type);
+	localInfo->transportType =
+	    IceTransport::NiceTransportTypeToCandidateTransportType(local->transport);
+
+	nice_address_to_string(&remote->addr, ipaddr);
+	remoteInfo->address = std::string(ipaddr);
+	remoteInfo->port = nice_address_get_port(&remote->addr);
+	remoteInfo->type = IceTransport::NiceTypeToCandidateType(remote->type);
+	remoteInfo->transportType =
+	    IceTransport::NiceTransportTypeToCandidateTransportType(remote->transport);
+
+	return true;
+}
+
+const CandidateType IceTransport::NiceTypeToCandidateType(NiceCandidateType type) {
+	switch (type) {
+	case NiceCandidateType::NICE_CANDIDATE_TYPE_PEER_REFLEXIVE:
+		return CandidateType::PeerReflexive;
+	case NiceCandidateType::NICE_CANDIDATE_TYPE_RELAYED:
+		return CandidateType::Relayed;
+	case NiceCandidateType::NICE_CANDIDATE_TYPE_SERVER_REFLEXIVE:
+		return CandidateType::ServerReflexive;
+	default:
+		return CandidateType::Host;
+	}
+}
+
+const CandidateTransportType
+IceTransport::NiceTransportTypeToCandidateTransportType(NiceCandidateTransport type) {
+	switch (type) {
+	case NiceCandidateTransport::NICE_CANDIDATE_TRANSPORT_TCP_ACTIVE:
+		return CandidateTransportType::TcpActive;
+	case NiceCandidateTransport::NICE_CANDIDATE_TRANSPORT_TCP_PASSIVE:
+		return CandidateTransportType::TcpPassive;
+	case NiceCandidateTransport::NICE_CANDIDATE_TRANSPORT_TCP_SO:
+		return CandidateTransportType::TcpSo;
+	default:
+		return CandidateTransportType::Udp;
+	}
 }
 
 } // namespace rtc
+
+#endif

src/icetransport.hpp

@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2019 Paul-Louis Ageneau
+ * Copyright (c) 2019-2020 Paul-Louis Ageneau
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -26,29 +26,23 @@
 #include "peerconnection.hpp"
 #include "transport.hpp"
 
-extern "C" {
+#if USE_JUICE
+#include <juice/juice.h>
+#else
 #include <nice/agent.h>
-}
+#endif
 
 #include <atomic>
+#include <chrono>
 #include <thread>
 
 namespace rtc {
 
 class IceTransport : public Transport {
 public:
-	enum class State : uint32_t {
-		Disconnected = NICE_COMPONENT_STATE_DISCONNECTED,
-		Connecting = NICE_COMPONENT_STATE_CONNECTING,
-		Connected = NICE_COMPONENT_STATE_CONNECTED,
-		Ready = NICE_COMPONENT_STATE_READY,
-		Failed = NICE_COMPONENT_STATE_FAILED
-	};
-
 	enum class GatheringState { New = 0, InProgress = 1, Complete = 2 };
 
 	using candidate_callback = std::function<void(const Candidate &candidate)>;
-	using state_callback = std::function<void(State state)>;
 	using gathering_state_callback = std::function<void(GatheringState state)>;
 
 	IceTransport(const Configuration &config, Description::Role role,
@@ -57,40 +51,58 @@ public:
 	~IceTransport();
 
 	Description::Role role() const;
-	State state() const;
+	GatheringState gatheringState() const;
-	GatheringState gyyatheringState() const;
 	Description getLocalDescription(Description::Type type) const;
 	void setRemoteDescription(const Description &description);
-	void gatherLocalCandidates();
 	bool addRemoteCandidate(const Candidate &candidate);
+	void gatherLocalCandidates();
 
-	bool send(message_ptr message);
+	std::optional<string> getLocalAddress() const;
+	std::optional<string> getRemoteAddress() const;
+
+	bool stop() override;
+	bool send(message_ptr message) override; // false if dropped
+
+#if !USE_JUICE
+	bool getSelectedCandidatePair(CandidateInfo *local, CandidateInfo *remote);
+#endif
 
 private:
-	void incoming(message_ptr message);
+	bool outgoing(message_ptr message) override;
-	void incoming(const byte *data, int size);
-	void outgoing(message_ptr message);
 
-	void changeState(State state);
 	void changeGatheringState(GatheringState state);
 
+	void processStateChange(unsigned int state);
 	void processCandidate(const string &candidate);
 	void processGatheringDone();
-	void processStateChange(uint32_t state);
+	void processTimeout();
 
 	Description::Role mRole;
 	string mMid;
-	std::atomic<State> mState;
+	std::chrono::milliseconds mTrickleTimeout;
 	std::atomic<GatheringState> mGatheringState;
 
+	candidate_callback mCandidateCallback;
+	gathering_state_callback mGatheringStateChangeCallback;
+
+#if USE_JUICE
+	std::unique_ptr<juice_agent_t, void (*)(juice_agent_t *)> mAgent;
+	string mStunHostname;
+	string mStunService;
+
+	static void StateChangeCallback(juice_agent_t *agent, juice_state_t state, void *user_ptr);
+	static void CandidateCallback(juice_agent_t *agent, const char *sdp, void *user_ptr);
+	static void GatheringDoneCallback(juice_agent_t *agent, void *user_ptr);
+	static void RecvCallback(juice_agent_t *agent, const char *data, size_t size, void *user_ptr);
+	static void LogCallback(juice_log_level_t level, const char *message);
+#else
 	uint32_t mStreamId = 0;
 	std::unique_ptr<NiceAgent, void (*)(gpointer)> mNiceAgent;
 	std::unique_ptr<GMainLoop, void (*)(GMainLoop *)> mMainLoop;
 	std::thread mMainLoopThread;
+	guint mTimeoutId = 0;
 
-	candidate_callback mCandidateCallback;
+	static string AddressToString(const NiceAddress &addr);
-	state_callback mStateChangeCallback;
-	gathering_state_callback mGatheringStateChangeCallback;
 
 	static void CandidateCallback(NiceAgent *agent, NiceCandidate *candidate, gpointer userData);
 	static void GatheringDoneCallback(NiceAgent *agent, guint streamId, gpointer userData);
@@ -98,8 +110,12 @@ private:
 	                                guint state, gpointer userData);
 	static void RecvCallback(NiceAgent *agent, guint stream_id, guint component_id, guint len,
 	                         gchar *buf, gpointer userData);
+	static gboolean TimeoutCallback(gpointer userData);
 	static void LogCallback(const gchar *log_domain, GLogLevelFlags log_level, const gchar *message,
 	                        gpointer user_data);
+	static const CandidateType NiceTypeToCandidateType(NiceCandidateType type);
+	static const CandidateTransportType NiceTransportTypeToCandidateTransportType(NiceCandidateTransport type);
+#endif
 };
 
 } // namespace rtc

src/init.cpp

@@ -0,0 +1,105 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "init.hpp"
+
+#include "certificate.hpp"
+#include "dtlstransport.hpp"
+#include "sctptransport.hpp"
+#include "tls.hpp"
+
+#if RTC_ENABLE_WEBSOCKET
+#include "tlstransport.hpp"
+#endif
+
+#if RTC_ENABLE_MEDIA
+#include "dtlssrtptransport.hpp"
+#endif
+
+#ifdef _WIN32
+#include <winsock2.h>
+#endif
+
+using std::shared_ptr;
+
+namespace rtc {
+
+std::weak_ptr<Init> Init::Weak;
+init_token Init::Global;
+std::mutex Init::Mutex;
+
+init_token Init::Token() {
+	std::lock_guard lock(Mutex);
+
+	if (!Global) {
+		if (auto token = Weak.lock())
+			Global = token;
+		else
+			Global = shared_ptr<Init>(new Init());
+	}
+	return Global;
+}
+
+void Init::Preload() {
+	Token();                   // pre-init
+	make_certificate().wait(); // preload certificate
+}
+
+void Init::Cleanup() { Global.reset(); }
+
+Init::Init() {
+#ifdef _WIN32
+	WSADATA wsaData;
+	if (WSAStartup(MAKEWORD(2, 2), &wsaData))
+		throw std::runtime_error("WSAStartup failed, error=" + std::to_string(WSAGetLastError()));
+#endif
+
+#if USE_GNUTLS
+		// Nothing to do
+#else
+	openssl::init();
+#endif
+
+	SctpTransport::Init();
+	DtlsTransport::Init();
+#if RTC_ENABLE_WEBSOCKET
+	TlsTransport::Init();
+#endif
+#if RTC_ENABLE_MEDIA
+	DtlsSrtpTransport::Init();
+#endif
+}
+
+Init::~Init() {
+	CleanupCertificateCache();
+	SctpTransport::Cleanup();
+	DtlsTransport::Cleanup();
+#if RTC_ENABLE_WEBSOCKET
+	TlsTransport::Cleanup();
+#endif
+#if RTC_ENABLE_MEDIA
+	DtlsSrtpTransport::Cleanup();
+#endif
+
+#ifdef _WIN32
+	WSACleanup();
+#endif
+}
+
+} // namespace rtc
+

src/log.cpp

@@ -0,0 +1,42 @@
+/**
+ * Copyright (c) 2019-2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "log.hpp"
+
+#include "plog/Appenders/ColorConsoleAppender.h"
+#include "plog/Log.h"
+#include "plog/Logger.h"
+
+namespace rtc {
+
+void InitLogger(LogLevel level) { InitLogger(static_cast<plog::Severity>(level)); }
+
+void InitLogger(plog::Severity severity, plog::IAppender *appender) {
+	static plog::ColorConsoleAppender<plog::TxtFormatter> consoleAppender;
+	static plog::Logger<0> *logger = nullptr;
+	if (!logger) {
+		logger = &plog::init(severity, appender ? appender : &consoleAppender);
+		PLOG_DEBUG << "Logger initialized";
+	} else {
+		logger->setMaxSeverity(severity);
+		if (appender)
+			logger->addAppender(appender);
+	}
+}
+}
+

src/peerconnection.cpp

@@ -20,23 +20,43 @@
 #include "certificate.hpp"
 #include "dtlstransport.hpp"
 #include "icetransport.hpp"
+#include "include.hpp"
 #include "sctptransport.hpp"
 
-#include <iostream>
+#if RTC_ENABLE_MEDIA
+#include "dtlssrtptransport.hpp"
+#endif
+
+#include <thread>
 
 namespace rtc {
 
 using namespace std::placeholders;
 
-using std::function;
 using std::shared_ptr;
+using std::weak_ptr;
 
 PeerConnection::PeerConnection() : PeerConnection(Configuration()) {}
 
 PeerConnection::PeerConnection(const Configuration &config)
-    : mConfig(config), mCertificate(make_certificate("libdatachannel")), mState(State::New) {}
+    : mConfig(config), mCertificate(make_certificate()), mState(State::New),
+      mGatheringState(GatheringState::New) {
+	PLOG_VERBOSE << "Creating PeerConnection";
 
-PeerConnection::~PeerConnection() {}
+	if (config.portRangeEnd && config.portRangeBegin > config.portRangeEnd)
+		throw std::invalid_argument("Invalid port range");
+}
+
+PeerConnection::~PeerConnection() {
+	close();
+	PLOG_VERBOSE << "Destroying PeerConnection";
+}
+
+void PeerConnection::close() {
+	PLOG_VERBOSE << "Closing PeerConnection";
+	closeDataChannels();
+	closeTransports();
+}
 
 const Configuration *PeerConnection::config() const { return &mConfig; }
 
@@ -44,60 +64,139 @@ PeerConnection::State PeerConnection::state() const { return mState; }
 
 PeerConnection::GatheringState PeerConnection::gatheringState() const { return mGatheringState; }
 
-std::optional<Description> PeerConnection::localDescription() const { return mLocalDescription; }
+std::optional<Description> PeerConnection::localDescription() const {
+	std::lock_guard lock(mLocalDescriptionMutex);
+	return mLocalDescription;
+}
 
-std::optional<Description> PeerConnection::remoteDescription() const { return mRemoteDescription; }
+std::optional<Description> PeerConnection::remoteDescription() const {
+	std::lock_guard lock(mRemoteDescriptionMutex);
+	return mRemoteDescription;
+}
+
+void PeerConnection::setLocalDescription(std::optional<Description> description) {
+	if (auto iceTransport = std::atomic_load(&mIceTransport)) {
+		throw std::logic_error("Local description is already set");
+	} else {
+		// RFC 5763: The endpoint that is the offerer MUST use the setup attribute value of
+		// setup:actpass.
+		// See https://tools.ietf.org/html/rfc5763#section-5
+		iceTransport = initIceTransport(Description::Role::ActPass);
+		Description localDescription = iceTransport->getLocalDescription(Description::Type::Offer);
+		if (description)
+			localDescription.addMedia(*description);
+		processLocalDescription(localDescription);
+		iceTransport->gatherLocalCandidates();
+	}
+}
 
 void PeerConnection::setRemoteDescription(Description description) {
-	if (!mIceTransport) {
+	description.hintType(localDescription() ? Description::Type::Answer : Description::Type::Offer);
-		initIceTransport(Description::Role::ActPass);
+	auto type = description.type();
-		mIceTransport->setRemoteDescription(description);
+	auto remoteCandidates = description.extractCandidates(); // Candidates will be added at the end
-		processLocalDescription(mIceTransport->getLocalDescription(Description::Type::Answer));
+
-		mIceTransport->gatherLocalCandidates();
+	auto iceTransport = std::atomic_load(&mIceTransport);
-	} else {
+	if (!iceTransport)
-		mIceTransport->setRemoteDescription(description);
+		iceTransport = initIceTransport(Description::Role::ActPass);
+	iceTransport->setRemoteDescription(description);
+
+	{
+		std::lock_guard lock(mRemoteDescriptionMutex);
+		mRemoteDescription.emplace(std::move(description));
 	}
 
-	mRemoteDescription.emplace(std::move(description));
+	if (type == Description::Type::Offer) {
+		// This is an offer and we are the answerer.
+		Description localDescription = iceTransport->getLocalDescription(Description::Type::Answer);
+		localDescription.addMedia(description); // blindly accept media
+		processLocalDescription(localDescription);
+		iceTransport->gatherLocalCandidates();
+	} else {
+		// This is an answer and we are the offerer.
+		auto sctpTransport = std::atomic_load(&mSctpTransport);
+		if (!sctpTransport && iceTransport->role() == Description::Role::Active) {
+			// Since we assumed passive role during DataChannel creation, we need to shift the
+			// stream numbers by one to shift them from odd to even.
+			std::unique_lock lock(mDataChannelsMutex); // we are going to swap the container
+			decltype(mDataChannels) newDataChannels;
+			auto it = mDataChannels.begin();
+			while (it != mDataChannels.end()) {
+				auto channel = it->second.lock();
+				if (channel->stream() % 2 == 1)
+					channel->mStream -= 1;
+				newDataChannels.emplace(channel->stream(), channel);
+				++it;
+			}
+			std::swap(mDataChannels, newDataChannels);
+		}
+	}
+
+	for (const auto &candidate : remoteCandidates)
+		addRemoteCandidate(candidate);
 }
 
 void PeerConnection::addRemoteCandidate(Candidate candidate) {
-	if (!mRemoteDescription || !mIceTransport)
+
+	auto iceTransport = std::atomic_load(&mIceTransport);
+	if (!mRemoteDescription || !iceTransport)
 		throw std::logic_error("Remote candidate set without remote description");
 
-	if (mIceTransport->addRemoteCandidate(candidate))
+	if (candidate.resolve(Candidate::ResolveMode::Simple)) {
-		mRemoteDescription->addCandidate(std::move(candidate));
+		iceTransport->addRemoteCandidate(candidate);
+	} else {
+		// OK, we might need a lookup, do it asynchronously
+		weak_ptr<IceTransport> weakIceTransport{iceTransport};
+		std::thread t([weakIceTransport, candidate]() mutable {
+			if (candidate.resolve(Candidate::ResolveMode::Lookup))
+				if (auto iceTransport = weakIceTransport.lock())
+					iceTransport->addRemoteCandidate(candidate);
+		});
+		t.detach();
+	}
+
+	std::lock_guard lock(mRemoteDescriptionMutex);
+	mRemoteDescription->addCandidate(candidate);
+}
+
+std::optional<string> PeerConnection::localAddress() const {
+	auto iceTransport = std::atomic_load(&mIceTransport);
+	return iceTransport ? iceTransport->getLocalAddress() : nullopt;
+}
+
+std::optional<string> PeerConnection::remoteAddress() const {
+	auto iceTransport = std::atomic_load(&mIceTransport);
+	return iceTransport ? iceTransport->getRemoteAddress() : nullopt;
 }
 
 shared_ptr<DataChannel> PeerConnection::createDataChannel(const string &label,
                                                           const string &protocol,
                                                           const Reliability &reliability) {
-	// The active side must use streams with even identifiers, whereas the passive side must use
+	// RFC 5763: The answerer MUST use either a setup attribute value of setup:active or
-	// streams with odd identifiers.
+	// setup:passive. [...] Thus, setup:active is RECOMMENDED.
-	// See https://tools.ietf.org/html/draft-ietf-rtcweb-data-protocol-09#section-6
+	// See https://tools.ietf.org/html/rfc5763#section-5
-	auto role = mIceTransport ? mIceTransport->role() : Description::Role::Active;
+	// Therefore, we assume passive role when we are the offerer.
-	unsigned int stream = (role == Description::Role::Active) ? 0 : 1;
+	auto iceTransport = std::atomic_load(&mIceTransport);
-	while (mDataChannels.find(stream) != mDataChannels.end()) {
+	auto role = iceTransport ? iceTransport->role() : Description::Role::Passive;
-		stream += 2;
-		if (stream >= 65535)
-			throw std::runtime_error("Too many DataChannels");
-	}
 
-	auto channel = std::make_shared<DataChannel>(stream, label, protocol, reliability);
+	auto channel = emplaceDataChannel(role, label, protocol, reliability);
-	mDataChannels.insert(std::make_pair(stream, channel));
 
-	if (!mIceTransport) {
+	if (!iceTransport) {
-		initIceTransport(Description::Role::Active);
+		// RFC 5763: The endpoint that is the offerer MUST use the setup attribute value of
-		processLocalDescription(mIceTransport->getLocalDescription(Description::Type::Offer));
+		// setup:actpass.
-		mIceTransport->gatherLocalCandidates();
+		// See https://tools.ietf.org/html/rfc5763#section-5
-	} else if (mSctpTransport && mSctpTransport->state() == SctpTransport::State::Connected) {
+		iceTransport = initIceTransport(Description::Role::ActPass);
-		channel->open(mSctpTransport);
+		processLocalDescription(iceTransport->getLocalDescription(Description::Type::Offer));
+		iceTransport->gatherLocalCandidates();
+	} else {
+		if (auto transport = std::atomic_load(&mSctpTransport))
+			if (transport->state() == SctpTransport::State::Connected)
+				channel->open(transport);
 	}
 	return channel;
 }
 
 void PeerConnection::onDataChannel(
-    std::function<void(std::shared_ptr<DataChannel> dataChannel)> callback) {
+    std::function<void(shared_ptr<DataChannel> dataChannel)> callback) {
 	mDataChannelCallback = callback;
 }
 
@@ -118,10 +217,50 @@ void PeerConnection::onGatheringStateChange(std::function<void(GatheringState st
 	mGatheringStateChangeCallback = callback;
 }
 
-void PeerConnection::initIceTransport(Description::Role role) {
+bool PeerConnection::hasMedia() const {
-	mIceTransport = std::make_shared<IceTransport>(
+	auto local = localDescription();
-	    mConfig, role, std::bind(&PeerConnection::processLocalCandidate, this, _1),
+	auto remote = remoteDescription();
-	    [this](IceTransport::State state) {
+	return (local && local->hasMedia()) || (remote && remote->hasMedia());
+}
+
+void PeerConnection::sendMedia(const binary &packet) {
+	outgoingMedia(make_message(packet.begin(), packet.end(), Message::Binary));
+}
+
+void PeerConnection::send(const byte *packet, size_t size) {
+	outgoingMedia(make_message(packet, packet + size, Message::Binary));
+}
+
+void PeerConnection::onMedia(std::function<void(const binary &packet)> callback) {
+	mMediaCallback = callback;
+}
+
+void PeerConnection::outgoingMedia(message_ptr message) {
+	if (!hasMedia())
+		throw std::runtime_error("PeerConnection has no media support");
+
+#if RTC_ENABLE_MEDIA
+	auto transport = std::atomic_load(&mDtlsTransport);
+	if (!transport)
+		throw std::runtime_error("PeerConnection is not open");
+
+	std::dynamic_pointer_cast<DtlsSrtpTransport>(transport)->send(message);
+#else
+	PLOG_WARNING << "Ignoring sent media (not compiled with SRTP support)";
+#endif
+}
+
+shared_ptr<IceTransport> PeerConnection::initIceTransport(Description::Role role) {
+	try {
+		if (auto transport = std::atomic_load(&mIceTransport))
+			return transport;
+
+		auto transport = std::make_shared<IceTransport>(
+		    mConfig, role, weak_bind(&PeerConnection::processLocalCandidate, this, _1),
+		    [this, weak_this = weak_from_this()](IceTransport::State state) {
+			    auto shared_this = weak_this.lock();
+			    if (!shared_this)
+				    return;
 			    switch (state) {
 			    case IceTransport::State::Connecting:
 				    changeState(State::Connecting);
@@ -129,22 +268,27 @@ void PeerConnection::initIceTransport(Description::Role role) {
 			    case IceTransport::State::Failed:
 				    changeState(State::Failed);
 				    break;
-		    case IceTransport::State::Ready:
+			    case IceTransport::State::Connected:
 				    initDtlsTransport();
 				    break;
+			    case IceTransport::State::Disconnected:
+				    changeState(State::Disconnected);
+				    break;
 			    default:
 				    // Ignore
 				    break;
 			    }
 		    },
-	    [this](IceTransport::GatheringState state) {
+		    [this, weak_this = weak_from_this()](IceTransport::GatheringState state) {
+			    auto shared_this = weak_this.lock();
+			    if (!shared_this)
+				    return;
 			    switch (state) {
 			    case IceTransport::GatheringState::InProgress:
 				    changeGatheringState(GatheringState::InProgress);
 				    break;
 			    case IceTransport::GatheringState::Complete:
-			    if (mLocalDescription)
+				    endLocalCandidates();
-				    mLocalDescription->endCandidates();
 				    changeGatheringState(GatheringState::Complete);
 				    break;
 			    default:
@@ -152,12 +296,36 @@ void PeerConnection::initIceTransport(Description::Role role) {
 				    break;
 			    }
 		    });
+
+		std::atomic_store(&mIceTransport, transport);
+		if (mState == State::Closed) {
+			mIceTransport.reset();
+			transport->stop();
+			throw std::runtime_error("Connection is closed");
+		}
+		return transport;
+
+	} catch (const std::exception &e) {
+		PLOG_ERROR << e.what();
+		changeState(State::Failed);
+		throw std::runtime_error("ICE transport initialization failed");
+	}
 }
 
-void PeerConnection::initDtlsTransport() {
+shared_ptr<DtlsTransport> PeerConnection::initDtlsTransport() {
-	mDtlsTransport = std::make_shared<DtlsTransport>(
+	try {
-	    mIceTransport, mCertificate, std::bind(&PeerConnection::checkFingerprint, this, _1),
+		if (auto transport = std::atomic_load(&mDtlsTransport))
-	    [this](DtlsTransport::State state) {
+			return transport;
+
+		auto certificate = mCertificate.get();
+		auto lower = std::atomic_load(&mIceTransport);
+		auto verifierCallback = weak_bind(&PeerConnection::checkFingerprint, this, _1);
+		auto stateChangeCallback = [this,
+		                            weak_this = weak_from_this()](DtlsTransport::State state) {
+			auto shared_this = weak_this.lock();
+			if (!shared_this)
+				return;
+
 			switch (state) {
 			case DtlsTransport::State::Connected:
 				initSctpTransport();
@@ -165,27 +333,82 @@ void PeerConnection::initDtlsTransport() {
 			case DtlsTransport::State::Failed:
 				changeState(State::Failed);
 				break;
+			case DtlsTransport::State::Disconnected:
+				changeState(State::Disconnected);
+				break;
 			default:
 				// Ignore
 				break;
 			}
-	    });
+		};
+
+		shared_ptr<DtlsTransport> transport;
+		if (hasMedia()) {
+#if RTC_ENABLE_MEDIA
+			PLOG_INFO << "This connection requires media support";
+
+			// DTLS-SRTP
+			transport = std::make_shared<DtlsSrtpTransport>(
+			    lower, certificate, verifierCallback,
+			    std::bind(&PeerConnection::forwardMedia, this, _1), stateChangeCallback);
+#else
+			PLOG_WARNING << "Ignoring media support (not compiled with SRTP support)";
+#endif
+		}
+
+		if (!transport) {
+			// DTLS only
+			transport = std::make_shared<DtlsTransport>(lower, certificate, verifierCallback,
+			                                            stateChangeCallback);
+		}
+
+		std::atomic_store(&mDtlsTransport, transport);
+		if (mState == State::Closed) {
+			mDtlsTransport.reset();
+			transport->stop();
+			throw std::runtime_error("Connection is closed");
+		}
+		return transport;
+
+	} catch (const std::exception &e) {
+		PLOG_ERROR << e.what();
+		changeState(State::Failed);
+		throw std::runtime_error("DTLS transport initialization failed");
+	}
 }
 
-void PeerConnection::initSctpTransport() {
+shared_ptr<SctpTransport> PeerConnection::initSctpTransport() {
-	uint16_t sctpPort = mRemoteDescription->sctpPort().value_or(DEFAULT_SCTP_PORT);
+	try {
-	mSctpTransport = std::make_shared<SctpTransport>(
+		if (auto transport = std::atomic_load(&mSctpTransport))
-	    mDtlsTransport, sctpPort, std::bind(&PeerConnection::forwardMessage, this, _1),
+			return transport;
-	    [this](SctpTransport::State state) {
+
+		uint16_t sctpPort = remoteDescription()->sctpPort().value_or(DEFAULT_SCTP_PORT);
+		auto lower = std::atomic_load(&mDtlsTransport);
+		auto transport = std::make_shared<SctpTransport>(
+		    lower, sctpPort, weak_bind(&PeerConnection::forwardMessage, this, _1),
+		    weak_bind(&PeerConnection::forwardBufferedAmount, this, _1, _2),
+		    [this, weak_this = weak_from_this()](SctpTransport::State state) {
+			    auto shared_this = weak_this.lock();
+			    if (!shared_this)
+				    return;
 			    switch (state) {
 			    case SctpTransport::State::Connected:
 				    changeState(State::Connected);
 				    openDataChannels();
 				    break;
 			    case SctpTransport::State::Failed:
+				    LOG_WARNING << "SCTP transport failed";
+				    remoteCloseDataChannels();
+#if RTC_ENABLE_MEDIA
+				    // Ignore SCTP failure if media is present
+				    if (!hasMedia())
 					    changeState(State::Failed);
+#else
+				    changeState(State::Failed);
+#endif
 				    break;
 			    case SctpTransport::State::Disconnected:
+				    remoteCloseDataChannels();
 				    changeState(State::Disconnected);
 				    break;
 			    default:
@@ -193,9 +416,60 @@ void PeerConnection::initSctpTransport() {
 				    break;
 			    }
 		    });
+
+		std::atomic_store(&mSctpTransport, transport);
+		if (mState == State::Closed) {
+			mSctpTransport.reset();
+			transport->stop();
+			throw std::runtime_error("Connection is closed");
+		}
+		return transport;
+
+	} catch (const std::exception &e) {
+		PLOG_ERROR << e.what();
+		changeState(State::Failed);
+		throw std::runtime_error("SCTP transport initialization failed");
+	}
+}
+
+void PeerConnection::closeTransports() {
+	PLOG_VERBOSE << "Closing transports";
+
+	// Change state to sink state Closed to block init methods
+	changeState(State::Closed);
+
+	// Reset callbacks now that state is changed
+	resetCallbacks();
+
+	// Pass the references to a thread, allowing to terminate a transport from its own thread
+	auto sctp = std::atomic_exchange(&mSctpTransport, decltype(mSctpTransport)(nullptr));
+	auto dtls = std::atomic_exchange(&mDtlsTransport, decltype(mDtlsTransport)(nullptr));
+	auto ice = std::atomic_exchange(&mIceTransport, decltype(mIceTransport)(nullptr));
+	if (sctp || dtls || ice) {
+		std::thread t([sctp, dtls, ice, token = mInitToken]() mutable {
+			if (sctp)
+				sctp->stop();
+			if (dtls)
+				dtls->stop();
+			if (ice)
+				ice->stop();
+
+			sctp.reset();
+			dtls.reset();
+			ice.reset();
+		});
+		t.detach();
+	}
+}
+
+void PeerConnection::endLocalCandidates() {
+	std::lock_guard lock(mLocalDescriptionMutex);
+	if (mLocalDescription)
+		mLocalDescription->endCandidates();
 }
 
 bool PeerConnection::checkFingerprint(const std::string &fingerprint) const {
+	std::lock_guard lock(mRemoteDescriptionMutex);
 	if (auto expectedFingerprint =
 	        mRemoteDescription ? mRemoteDescription->fingerprint() : nullopt) {
 		return *expectedFingerprint == fingerprint;
@@ -204,34 +478,31 @@ bool PeerConnection::checkFingerprint(const std::string &fingerprint) const {
 }
 
 void PeerConnection::forwardMessage(message_ptr message) {
-	if (!mIceTransport || !mSctpTransport)
-		throw std::logic_error("Got a DataChannel message without transport");
-
 	if (!message) {
-		closeDataChannels();
+		remoteCloseDataChannels();
 		return;
 	}
 
-	shared_ptr<DataChannel> channel;
+	auto channel = findDataChannel(message->stream);
-	if (auto it = mDataChannels.find(message->stream); it != mDataChannels.end()) {
+
-		channel = it->second.lock();
+	auto iceTransport = std::atomic_load(&mIceTransport);
-		if (!channel || channel->isClosed()) {
+	auto sctpTransport = std::atomic_load(&mSctpTransport);
-			mDataChannels.erase(it);
+	if (!iceTransport || !sctpTransport)
-			channel = nullptr;
+		return;
-		}
-	}
 
 	if (!channel) {
 		const byte dataChannelOpenMessage{0x03};
-		unsigned int remoteParity = (mIceTransport->role() == Description::Role::Active) ? 1 : 0;
+		unsigned int remoteParity = (iceTransport->role() == Description::Role::Active) ? 1 : 0;
 		if (message->type == Message::Control && *message->data() == dataChannelOpenMessage &&
 		    message->stream % 2 == remoteParity) {
-			channel = std::make_shared<DataChannel>(message->stream, mSctpTransport);
+			channel =
-			channel->onOpen(std::bind(&PeerConnection::triggerDataChannel, this, channel));
+			    std::make_shared<DataChannel>(shared_from_this(), sctpTransport, message->stream);
+			channel->onOpen(weak_bind(&PeerConnection::triggerDataChannel, this,
+			                          weak_ptr<DataChannel>{channel}));
 			mDataChannels.insert(std::make_pair(message->stream, channel));
 		} else {
-			// Invalid, close the DataChannel by resetting the stream
+			// Invalid, close the DataChannel
-			mSctpTransport->reset(message->stream);
+			sctpTransport->close(message->stream);
 			return;
 		}
 	}
@@ -239,64 +510,190 @@ void PeerConnection::forwardMessage(message_ptr message) {
 	channel->incoming(message);
 }
 
+void PeerConnection::forwardMedia(message_ptr message) {
+	if (message)
+		mMediaCallback(*message);
+}
+
+void PeerConnection::forwardBufferedAmount(uint16_t stream, size_t amount) {
+	if (auto channel = findDataChannel(stream))
+		channel->triggerBufferedAmount(amount);
+}
+
+shared_ptr<DataChannel> PeerConnection::emplaceDataChannel(Description::Role role,
+                                                           const string &label,
+                                                           const string &protocol,
+                                                           const Reliability &reliability) {
+	// The active side must use streams with even identifiers, whereas the passive side must use
+	// streams with odd identifiers.
+	// See https://tools.ietf.org/html/draft-ietf-rtcweb-data-protocol-09#section-6
+	std::unique_lock lock(mDataChannelsMutex); // we are going to emplace
+	unsigned int stream = (role == Description::Role::Active) ? 0 : 1;
+	while (mDataChannels.find(stream) != mDataChannels.end()) {
+		stream += 2;
+		if (stream >= 65535)
+			throw std::runtime_error("Too many DataChannels");
+	}
+	auto channel =
+	    std::make_shared<DataChannel>(shared_from_this(), stream, label, protocol, reliability);
+	mDataChannels.emplace(std::make_pair(stream, channel));
+	return channel;
+}
+
+shared_ptr<DataChannel> PeerConnection::findDataChannel(uint16_t stream) {
+	std::shared_lock lock(mDataChannelsMutex); // read-only
+	if (auto it = mDataChannels.find(stream); it != mDataChannels.end())
+		if (auto channel = it->second.lock())
+			return channel;
+
+	return nullptr;
+}
+
 void PeerConnection::iterateDataChannels(
     std::function<void(shared_ptr<DataChannel> channel)> func) {
+	// Iterate
+	{
+		std::shared_lock lock(mDataChannelsMutex); // read-only
 		auto it = mDataChannels.begin();
 		while (it != mDataChannels.end()) {
 			auto channel = it->second.lock();
-		if (!channel || channel->isClosed()) {
+			if (channel && !channel->isClosed())
+				func(channel);
+
+			++it;
+		}
+	}
+
+	// Cleanup
+	{
+		std::unique_lock lock(mDataChannelsMutex); // we are going to erase
+		auto it = mDataChannels.begin();
+		while (it != mDataChannels.end()) {
+			if (!it->second.lock()) {
 				it = mDataChannels.erase(it);
 				continue;
 			}
-		func(channel);
+
 			++it;
 		}
+	}
 }
 
 void PeerConnection::openDataChannels() {
-	iterateDataChannels([this](shared_ptr<DataChannel> channel) { channel->open(mSctpTransport); });
+	if (auto transport = std::atomic_load(&mSctpTransport))
+		iterateDataChannels([&](shared_ptr<DataChannel> channel) { channel->open(transport); });
 }
 
 void PeerConnection::closeDataChannels() {
-	iterateDataChannels([](shared_ptr<DataChannel> channel) { channel->close(); });
+	iterateDataChannels([&](shared_ptr<DataChannel> channel) { channel->close(); });
+}
+
+void PeerConnection::remoteCloseDataChannels() {
+	iterateDataChannels([&](shared_ptr<DataChannel> channel) { channel->remoteClose(); });
 }
 
 void PeerConnection::processLocalDescription(Description description) {
-	auto remoteSctpPort = mRemoteDescription ? mRemoteDescription->sctpPort() : nullopt;
+	std::optional<uint16_t> remoteSctpPort;
+	if (auto remote = remoteDescription())
+		remoteSctpPort = remote->sctpPort();
 
-	description.setFingerprint(mCertificate->fingerprint());
+	auto certificate = mCertificate.get(); // wait for certificate if not ready
-	description.setSctpPort(remoteSctpPort.value_or(DEFAULT_SCTP_PORT));
+
+	{
+		std::lock_guard lock(mLocalDescriptionMutex);
 		mLocalDescription.emplace(std::move(description));
+		mLocalDescription->setFingerprint(certificate->fingerprint());
+		mLocalDescription->setSctpPort(remoteSctpPort.value_or(DEFAULT_SCTP_PORT));
+		mLocalDescription->setMaxMessageSize(LOCAL_MAX_MESSAGE_SIZE);
+	}
 
-	if (mLocalDescriptionCallback)
 	mLocalDescriptionCallback(*mLocalDescription);
 }
 
 void PeerConnection::processLocalCandidate(Candidate candidate) {
+	std::lock_guard lock(mLocalDescriptionMutex);
 	if (!mLocalDescription)
 		throw std::logic_error("Got a local candidate without local description");
 
 	mLocalDescription->addCandidate(candidate);
 
-	if (mLocalCandidateCallback)
 	mLocalCandidateCallback(candidate);
 }
 
-void PeerConnection::triggerDataChannel(std::shared_ptr<DataChannel> dataChannel) {
+void PeerConnection::triggerDataChannel(weak_ptr<DataChannel> weakDataChannel) {
-	if (mDataChannelCallback)
+	auto dataChannel = weakDataChannel.lock();
+	if (!dataChannel)
+		return;
+
 	mDataChannelCallback(dataChannel);
 }
 
-void PeerConnection::changeState(State state) {
+bool PeerConnection::changeState(State state) {
-	mState = state;
+	State current;
-	if (mStateChangeCallback)
+	do {
+		current = mState.load();
+		if (current == state)
+			return true;
+		if (current == State::Closed)
+			return false;
+
+	} while (!mState.compare_exchange_weak(current, state));
+
 	mStateChangeCallback(state);
+	return true;
 }
 
-void PeerConnection::changeGatheringState(GatheringState state) {
+bool PeerConnection::changeGatheringState(GatheringState state) {
-	mGatheringState = state;
+	if (mGatheringState.exchange(state) != state)
-	if (mGatheringStateChangeCallback)
 		mGatheringStateChangeCallback(state);
+	return true;
+}
+
+void PeerConnection::resetCallbacks() {
+	// Unregister all callbacks
+	mDataChannelCallback = nullptr;
+	mLocalDescriptionCallback = nullptr;
+	mLocalCandidateCallback = nullptr;
+	mStateChangeCallback = nullptr;
+	mGatheringStateChangeCallback = nullptr;
+}
+
+bool PeerConnection::getSelectedCandidatePair(CandidateInfo *local, CandidateInfo *remote) {
+#if not USE_JUICE
+	auto iceTransport = std::atomic_load(&mIceTransport);
+	return iceTransport->getSelectedCandidatePair(local, remote);
+#else
+	PLOG_WARNING << "getSelectedCandidatePair is not implemented for libjuice";
+	return false;
+#endif
+}
+
+void PeerConnection::clearStats() {
+	auto sctpTransport = std::atomic_load(&mSctpTransport);
+	if (sctpTransport)
+		return sctpTransport->clearStats();
+}
+
+size_t PeerConnection::bytesSent() {
+	auto sctpTransport = std::atomic_load(&mSctpTransport);
+	if (sctpTransport)
+		return sctpTransport->bytesSent();
+	return 0;
+}
+
+size_t PeerConnection::bytesReceived() {
+	auto sctpTransport = std::atomic_load(&mSctpTransport);
+	if (sctpTransport)
+		return sctpTransport->bytesReceived();
+	return 0;
+}
+
+std::optional<std::chrono::milliseconds> PeerConnection::rtt() {
+	auto sctpTransport = std::atomic_load(&mSctpTransport);
+	if (sctpTransport)
+		return sctpTransport->rtt();
+	PLOG_WARNING << "Could not load sctpTransport";
+	return std::nullopt;
 }
 
 } // namespace rtc
@@ -320,6 +717,9 @@ std::ostream &operator<<(std::ostream &out, const rtc::PeerConnection::State &st
 	case State::Failed:
 		str = "failed";
 		break;
+	case State::Closed:
+		str = "closed";
+		break;
 	default:
 		str = "unknown";
 		break;
@@ -346,4 +746,3 @@ std::ostream &operator<<(std::ostream &out, const rtc::PeerConnection::Gathering
 	}
 	return out << str;
 }
-

src/queue.hpp

@@ -1,90 +0,0 @@
-/**
- * Copyright (c) 2019 Paul-Louis Ageneau
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifndef RTC_QUEUE_H
-#define RTC_QUEUE_H
-
-#include "include.hpp"
-
-#include <atomic>
-#include <condition_variable>
-#include <mutex>
-#include <optional>
-#include <queue>
-
-namespace rtc {
-
-template <typename T> class Queue {
-public:
-	Queue();
-	~Queue();
-
-	void stop();
-	void push(const T &element);
-	std::optional<T> pop();
-
-	bool empty() const;
-
-private:
-	std::queue<T> mQueue;
-	std::condition_variable mCondition;
-	std::atomic<bool> mStopping;
-
-	mutable std::mutex mMutex;
-};
-
-template <typename T> Queue<T>::Queue() : mStopping(false) {}
-
-template <typename T> Queue<T>::~Queue() { stop(); }
-
-template <typename T> void Queue<T>::stop() {
-	std::lock_guard<std::mutex> lock(mMutex);
-	mStopping = true;
-	mCondition.notify_all();
-}
-
-template <typename T> void Queue<T>::push(const T &element) {
-	std::lock_guard<std::mutex> lock(mMutex);
-	if (mStopping)
-		return;
-	mQueue.push(element);
-	mCondition.notify_one();
-}
-
-template <typename T> std::optional<T> Queue<T>::pop() {
-	std::unique_lock<std::mutex> lock(mMutex);
-	while (mQueue.empty()) {
-		if (mStopping)
-			return nullopt;
-		mCondition.wait(lock);
-	}
-
-	std::optional<T> element = mQueue.front();
-	mQueue.pop();
-	return element;
-}
-
-template <typename T> bool Queue<T>::empty() const {
-	std::lock_guard<std::mutex> lock(mMutex);
-	return mQueue.empty();
-}
-
-} // namespace rtc
-
-#endif
-

src/rtc.cpp

@@ -16,12 +16,22 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include "include.hpp"
+
 #include "datachannel.hpp"
 #include "peerconnection.hpp"
 
+#if RTC_ENABLE_WEBSOCKET
+#include "websocket.hpp"
+#endif
+
 #include <rtc.h>
 
+#include <exception>
+#include <mutex>
+#include <type_traits>
 #include <unordered_map>
+#include <utility>
 
 using namespace rtc;
 using std::shared_ptr;
@@ -31,182 +41,475 @@ namespace {
 
 std::unordered_map<int, shared_ptr<PeerConnection>> peerConnectionMap;
 std::unordered_map<int, shared_ptr<DataChannel>> dataChannelMap;
+#if RTC_ENABLE_WEBSOCKET
+std::unordered_map<int, shared_ptr<WebSocket>> webSocketMap;
+#endif
 std::unordered_map<int, void *> userPointerMap;
+std::mutex mutex;
 int lastId = 0;
 
 void *getUserPointer(int id) {
+	std::lock_guard lock(mutex);
 	auto it = userPointerMap.find(id);
 	return it != userPointerMap.end() ? it->second : nullptr;
 }
 
-} // namespace
+void setUserPointer(int i, void *ptr) {
-
+	std::lock_guard lock(mutex);
-int rtcCreatePeerConnection(const char **iceServers, int iceServersCount) {
-	Configuration config;
-	for (int i = 0; i < iceServersCount; ++i) {
-		config.iceServers.emplace_back(IceServer(string(iceServers[i])));
-	}
-	int pc = ++lastId;
-	peerConnectionMap.emplace(std::make_pair(pc, std::make_shared<PeerConnection>(config)));
-	return pc;
-}
-
-void rtcDeletePeerConnection(int pc) { peerConnectionMap.erase(pc); }
-
-int rtcCreateDataChannel(int pc, const char *label) {
-	auto it = peerConnectionMap.find(pc);
-	if (it == peerConnectionMap.end())
-		return 0;
-	auto dataChannel = it->second->createDataChannel(string(label));
-	int dc = ++lastId;
-	dataChannelMap.emplace(std::make_pair(dc, dataChannel));
-	return dc;
-}
-
-void rtcDeleteDataChannel(int dc) { dataChannelMap.erase(dc); }
-
-void rtcSetDataChannelCallback(int pc, void (*dataChannelCallback)(int, void *)) {
-	auto it = peerConnectionMap.find(pc);
-	if (it == peerConnectionMap.end())
-		return;
-
-	it->second->onDataChannel([pc, dataChannelCallback](std::shared_ptr<DataChannel> dataChannel) {
-		int dc = ++lastId;
-		dataChannelMap.emplace(std::make_pair(dc, dataChannel));
-		dataChannelCallback(dc, getUserPointer(pc));
-	});
-}
-
-void rtcSetLocalDescriptionCallback(int pc, void (*descriptionCallback)(const char *, const char *,
-                                                                        void *)) {
-	auto it = peerConnectionMap.find(pc);
-	if (it == peerConnectionMap.end())
-		return;
-
-	it->second->onLocalDescription([pc, descriptionCallback](const Description &description) {
-		descriptionCallback(string(description).c_str(), description.typeString().c_str(),
-		                    getUserPointer(pc));
-	});
-}
-
-void rtcSetLocalCandidateCallback(int pc,
-                                  void (*candidateCallback)(const char *, const char *, void *)) {
-	auto it = peerConnectionMap.find(pc);
-	if (it == peerConnectionMap.end())
-		return;
-
-	it->second->onLocalCandidate([pc, candidateCallback](const Candidate &candidate) {
-		candidateCallback(candidate.candidate().c_str(), candidate.mid().c_str(),
-		                  getUserPointer(pc));
-	});
-}
-
-void rtcSetStateChangeCallback(int pc, void (*stateCallback)(rtc_state_t state, void *)) {
-	auto it = peerConnectionMap.find(pc);
-	if (it == peerConnectionMap.end())
-		return;
-
-	it->second->onStateChange([pc, stateCallback](PeerConnection::State state) {
-		stateCallback(static_cast<rtc_state_t>(state), getUserPointer(pc));
-	});
-}
-
-void rtcSetGatheringStateChangeCallback(int pc,
-                                         void (*gatheringStateCallback)(rtc_gathering_state_t state,
-                                                                        void *)) {
-	auto it = peerConnectionMap.find(pc);
-	if (it == peerConnectionMap.end())
-		return;
-
-	it->second->onGatheringStateChange(
-	    [pc, gatheringStateCallback](PeerConnection::GatheringState state) {
-		    gatheringStateCallback(static_cast<rtc_gathering_state_t>(state), getUserPointer(pc));
-	    });
-}
-
-void rtcSetRemoteDescription(int pc, const char *sdp, const char *type) {
-	auto it = peerConnectionMap.find(pc);
-	if (it == peerConnectionMap.end())
-		return;
-
-	it->second->setRemoteDescription(Description(string(sdp), type ? string(type) : ""));
-}
-
-void rtcAddRemoteCandidate(int pc, const char *candidate, const char *mid) {
-	auto it = peerConnectionMap.find(pc);
-	if (it == peerConnectionMap.end())
-		return;
-
-	it->second->addRemoteCandidate(Candidate(string(candidate), mid ? string(mid) : ""));
-}
-
-int rtcGetDataChannelLabel(int dc, char *buffer, int size) {
-	auto it = dataChannelMap.find(dc);
-	if (it == dataChannelMap.end())
-		return 0;
-
-	if (!size)
-		return 0;
-
-	string label = it->second->label();
-	size = std::min(size_t(size - 1), label.size());
-	std::copy(label.data(), label.data() + size, buffer);
-	buffer[size] = '\0';
-	return size + 1;
-}
-
-void rtcSetOpenCallback(int dc, void (*openCallback)(void *)) {
-	auto it = dataChannelMap.find(dc);
-	if (it == dataChannelMap.end())
-		return;
-
-	it->second->onOpen([dc, openCallback]() { openCallback(getUserPointer(dc)); });
-}
-
-void rtcSetErrorCallback(int dc, void (*errorCallback)(const char *, void *)) {
-	auto it = dataChannelMap.find(dc);
-	if (it == dataChannelMap.end())
-		return;
-
-	it->second->onError([dc, errorCallback](const string &error) {
-		errorCallback(error.c_str(), getUserPointer(dc));
-	});
-}
-
-void rtcSetMessageCallback(int dc, void (*messageCallback)(const char *, int, void *)) {
-	auto it = dataChannelMap.find(dc);
-	if (it == dataChannelMap.end())
-		return;
-
-	it->second->onMessage(
-	    [dc, messageCallback](const binary &b) {
-		    messageCallback(reinterpret_cast<const char *>(b.data()), b.size(), getUserPointer(dc));
-	    },
-	    [dc, messageCallback](const string &s) {
-		    messageCallback(s.c_str(), -1, getUserPointer(dc));
-	    });
-}
-
-int rtcSendMessage(int dc, const char *data, int size) {
-	auto it = dataChannelMap.find(dc);
-	if (it == dataChannelMap.end())
-		return 0;
-
-	if (size >= 0) {
-		auto b = reinterpret_cast<const byte *>(data);
-		it->second->send(b, size);
-		return size;
-	} else {
-		string s(data);
-		it->second->send(s);
-		return s.size();
-	}
-}
-
-void rtcSetUserPointer(int i, void *ptr) {
 	if (ptr)
 		userPointerMap.insert(std::make_pair(i, ptr));
 	else
 		userPointerMap.erase(i);
 }
 
+shared_ptr<PeerConnection> getPeerConnection(int id) {
+	std::lock_guard lock(mutex);
+	if (auto it = peerConnectionMap.find(id); it != peerConnectionMap.end())
+		return it->second;
+	else
+		throw std::invalid_argument("PeerConnection ID does not exist");
+}
+
+shared_ptr<DataChannel> getDataChannel(int id) {
+	std::lock_guard lock(mutex);
+	if (auto it = dataChannelMap.find(id); it != dataChannelMap.end())
+		return it->second;
+	else
+		throw std::invalid_argument("DataChannel ID does not exist");
+}
+
+int emplacePeerConnection(shared_ptr<PeerConnection> ptr) {
+	std::lock_guard lock(mutex);
+	int pc = ++lastId;
+	peerConnectionMap.emplace(std::make_pair(pc, ptr));
+	return pc;
+}
+
+int emplaceDataChannel(shared_ptr<DataChannel> ptr) {
+	std::lock_guard lock(mutex);
+	int dc = ++lastId;
+	dataChannelMap.emplace(std::make_pair(dc, ptr));
+	return dc;
+}
+
+void erasePeerConnection(int pc) {
+	std::lock_guard lock(mutex);
+	if (peerConnectionMap.erase(pc) == 0)
+		throw std::invalid_argument("PeerConnection ID does not exist");
+	userPointerMap.erase(pc);
+}
+
+void eraseDataChannel(int dc) {
+	std::lock_guard lock(mutex);
+	if (dataChannelMap.erase(dc) == 0)
+		throw std::invalid_argument("DataChannel ID does not exist");
+	userPointerMap.erase(dc);
+}
+
+#if RTC_ENABLE_WEBSOCKET
+shared_ptr<WebSocket> getWebSocket(int id) {
+	std::lock_guard lock(mutex);
+	if (auto it = webSocketMap.find(id); it != webSocketMap.end())
+		return it->second;
+	else
+		throw std::invalid_argument("WebSocket ID does not exist");
+}
+
+int emplaceWebSocket(shared_ptr<WebSocket> ptr) {
+	std::lock_guard lock(mutex);
+	int ws = ++lastId;
+	webSocketMap.emplace(std::make_pair(ws, ptr));
+	return ws;
+}
+
+void eraseWebSocket(int ws) {
+	std::lock_guard lock(mutex);
+	if (webSocketMap.erase(ws) == 0)
+		throw std::invalid_argument("WebSocket ID does not exist");
+	userPointerMap.erase(ws);
+}
+#endif
+
+shared_ptr<Channel> getChannel(int id) {
+	std::lock_guard lock(mutex);
+	if (auto it = dataChannelMap.find(id); it != dataChannelMap.end())
+		return it->second;
+#if RTC_ENABLE_WEBSOCKET
+	if (auto it = webSocketMap.find(id); it != webSocketMap.end())
+		return it->second;
+#endif
+	throw std::invalid_argument("DataChannel or WebSocket ID does not exist");
+}
+
+template <typename F> int wrap(F func) {
+	try {
+		return func();
+
+	} catch (const std::invalid_argument &e) {
+		PLOG_ERROR << e.what();
+		return RTC_ERR_INVALID;
+	} catch (const std::exception &e) {
+		PLOG_ERROR << e.what();
+		return RTC_ERR_FAILURE;
+	}
+}
+
+#define WRAP(statement)                                                                            \
+	wrap([&]() {                                                                                   \
+		statement;                                                                                 \
+		return RTC_ERR_SUCCESS;                                                                    \
+	})
+
+} // namespace
+
+void rtcInitLogger(rtcLogLevel level) { InitLogger(static_cast<LogLevel>(level)); }
+
+void rtcSetUserPointer(int i, void *ptr) { setUserPointer(i, ptr); }
+
+int rtcCreatePeerConnection(const rtcConfiguration *config) {
+	return WRAP({
+		Configuration c;
+		for (int i = 0; i < config->iceServersCount; ++i)
+			c.iceServers.emplace_back(string(config->iceServers[i]));
+
+		if (config->portRangeBegin || config->portRangeEnd) {
+			c.portRangeBegin = config->portRangeBegin;
+			c.portRangeEnd = config->portRangeEnd;
+		}
+
+		return emplacePeerConnection(std::make_shared<PeerConnection>(c));
+	});
+}
+
+int rtcDeletePeerConnection(int pc) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+		peerConnection->onDataChannel(nullptr);
+		peerConnection->onLocalDescription(nullptr);
+		peerConnection->onLocalCandidate(nullptr);
+		peerConnection->onStateChange(nullptr);
+		peerConnection->onGatheringStateChange(nullptr);
+
+		erasePeerConnection(pc);
+	});
+}
+
+int rtcCreateDataChannel(int pc, const char *label) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+		int dc = emplaceDataChannel(peerConnection->createDataChannel(string(label)));
+		rtcSetUserPointer(dc, getUserPointer(pc));
+		return dc;
+	});
+}
+
+int rtcDeleteDataChannel(int dc) {
+	return WRAP({
+		auto dataChannel = getDataChannel(dc);
+		dataChannel->onOpen(nullptr);
+		dataChannel->onClosed(nullptr);
+		dataChannel->onError(nullptr);
+		dataChannel->onMessage(nullptr);
+		dataChannel->onBufferedAmountLow(nullptr);
+		dataChannel->onAvailable(nullptr);
+
+		eraseDataChannel(dc);
+	});
+}
+
+#if RTC_ENABLE_WEBSOCKET
+int rtcCreateWebSocket(const char *url) {
+	return WRAP({
+		auto ws = std::make_shared<WebSocket>();
+		ws->open(url);
+		return emplaceWebSocket(ws);
+	});
+}
+
+int rtcDeleteWebsocket(int ws) {
+	return WRAP({
+		auto webSocket = getWebSocket(ws);
+		webSocket->onOpen(nullptr);
+		webSocket->onClosed(nullptr);
+		webSocket->onError(nullptr);
+		webSocket->onMessage(nullptr);
+		webSocket->onBufferedAmountLow(nullptr);
+		webSocket->onAvailable(nullptr);
+
+		eraseWebSocket(ws);
+	});
+}
+#endif
+
+int rtcSetDataChannelCallback(int pc, dataChannelCallbackFunc cb) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+		if (cb)
+			peerConnection->onDataChannel([pc, cb](std::shared_ptr<DataChannel> dataChannel) {
+				int dc = emplaceDataChannel(dataChannel);
+				void *ptr = getUserPointer(pc);
+				rtcSetUserPointer(dc, ptr);
+				cb(dc, ptr);
+			});
+		else
+			peerConnection->onDataChannel(nullptr);
+	});
+}
+
+int rtcSetLocalDescriptionCallback(int pc, descriptionCallbackFunc cb) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+		if (cb)
+			peerConnection->onLocalDescription([pc, cb](const Description &desc) {
+				cb(string(desc).c_str(), desc.typeString().c_str(), getUserPointer(pc));
+			});
+		else
+			peerConnection->onLocalDescription(nullptr);
+	});
+}
+
+int rtcSetLocalCandidateCallback(int pc, candidateCallbackFunc cb) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+		if (cb)
+			peerConnection->onLocalCandidate([pc, cb](const Candidate &cand) {
+				cb(cand.candidate().c_str(), cand.mid().c_str(), getUserPointer(pc));
+			});
+		else
+			peerConnection->onLocalCandidate(nullptr);
+	});
+}
+
+int rtcSetStateChangeCallback(int pc, stateChangeCallbackFunc cb) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+		if (cb)
+			peerConnection->onStateChange([pc, cb](PeerConnection::State state) {
+				cb(static_cast<rtcState>(state), getUserPointer(pc));
+			});
+		else
+			peerConnection->onStateChange(nullptr);
+	});
+}
+
+int rtcSetGatheringStateChangeCallback(int pc, gatheringStateCallbackFunc cb) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+		if (cb)
+			peerConnection->onGatheringStateChange([pc, cb](PeerConnection::GatheringState state) {
+				cb(static_cast<rtcGatheringState>(state), getUserPointer(pc));
+			});
+		else
+			peerConnection->onGatheringStateChange(nullptr);
+	});
+}
+
+int rtcSetRemoteDescription(int pc, const char *sdp, const char *type) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+
+		if (!sdp)
+			throw std::invalid_argument("Unexpected null pointer");
+
+		peerConnection->setRemoteDescription({string(sdp), type ? string(type) : ""});
+	});
+}
+
+int rtcAddRemoteCandidate(int pc, const char *cand, const char *mid) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+
+		if (!cand)
+			throw std::invalid_argument("Unexpected null pointer");
+
+		peerConnection->addRemoteCandidate({string(cand), mid ? string(mid) : ""});
+	});
+}
+
+int rtcGetLocalAddress(int pc, char *buffer, int size) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+
+		if (!buffer)
+			throw std::invalid_argument("Unexpected null pointer");
+
+		if (auto addr = peerConnection->localAddress()) {
+			size = std::min(size_t(size - 1), addr->size());
+			std::copy(addr->data(), addr->data() + size, buffer);
+			buffer[size] = '\0';
+			return size + 1;
+		}
+	});
+}
+
+int rtcGetRemoteAddress(int pc, char *buffer, int size) {
+	return WRAP({
+		auto peerConnection = getPeerConnection(pc);
+
+		if (!buffer)
+			throw std::invalid_argument("Unexpected null pointer");
+
+		if (auto addr = peerConnection->remoteAddress()) {
+			size = std::min(size_t(size - 1), addr->size());
+			std::copy(addr->data(), addr->data() + size, buffer);
+			buffer[size] = '\0';
+			return size + 1;
+		}
+	});
+}
+
+int rtcGetDataChannelLabel(int dc, char *buffer, int size) {
+	return WRAP({
+		auto dataChannel = getDataChannel(dc);
+
+		if (!buffer)
+			throw std::invalid_argument("Unexpected null pointer");
+
+		if (size >= 0) {
+			string label = dataChannel->label();
+			size = std::min(size_t(size - 1), label.size());
+			std::copy(label.data(), label.data() + size, buffer);
+			buffer[size] = '\0';
+			return size + 1;
+		} else {
+			return 0;
+		}
+	});
+}
+
+int rtcSetOpenCallback(int id, openCallbackFunc cb) {
+	return WRAP({
+		auto channel = getChannel(id);
+		if (cb)
+			channel->onOpen([id, cb]() { cb(getUserPointer(id)); });
+		else
+			channel->onOpen(nullptr);
+	});
+}
+
+int rtcSetClosedCallback(int id, closedCallbackFunc cb) {
+	return WRAP({
+		auto channel = getChannel(id);
+		if (cb)
+			channel->onClosed([id, cb]() { cb(getUserPointer(id)); });
+		else
+			channel->onClosed(nullptr);
+	});
+}
+
+int rtcSetErrorCallback(int id, errorCallbackFunc cb) {
+	return WRAP({
+		auto channel = getChannel(id);
+		if (cb)
+			channel->onError(
+			    [id, cb](const string &error) { cb(error.c_str(), getUserPointer(id)); });
+		else
+			channel->onError(nullptr);
+	});
+}
+
+int rtcSetMessageCallback(int id, messageCallbackFunc cb) {
+	return WRAP({
+		auto channel = getChannel(id);
+		if (cb)
+			channel->onMessage(
+			    [id, cb](const binary &b) {
+				    cb(reinterpret_cast<const char *>(b.data()), b.size(), getUserPointer(id));
+			    },
+			    [id, cb](const string &s) { cb(s.c_str(), -1, getUserPointer(id)); });
+		else
+			channel->onMessage(nullptr);
+	});
+}
+
+int rtcSendMessage(int id, const char *data, int size) {
+	return WRAP({
+		auto channel = getChannel(id);
+
+		if (!data)
+			throw std::invalid_argument("Unexpected null pointer");
+
+		if (size >= 0) {
+			auto b = reinterpret_cast<const byte *>(data);
+			channel->send(binary(b, b + size));
+			return size;
+		} else {
+			string str(data);
+			int len = str.size();
+			channel->send(std::move(str));
+			return len;
+		}
+	});
+}
+
+int rtcGetBufferedAmount(int id) {
+	return WRAP({
+		auto channel = getChannel(id);
+		return int(channel->bufferedAmount());
+	});
+}
+
+int rtcSetBufferedAmountLowThreshold(int id, int amount) {
+	return WRAP({
+		auto channel = getChannel(id);
+		channel->setBufferedAmountLowThreshold(size_t(amount));
+	});
+}
+
+int rtcSetBufferedAmountLowCallback(int id, bufferedAmountLowCallbackFunc cb) {
+	return WRAP({
+		auto channel = getChannel(id);
+		if (cb)
+			channel->onBufferedAmountLow([id, cb]() { cb(getUserPointer(id)); });
+		else
+			channel->onBufferedAmountLow(nullptr);
+	});
+}
+
+int rtcGetAvailableAmount(int id) {
+	return WRAP({ return int(getChannel(id)->availableAmount()); });
+}
+
+int rtcSetAvailableCallback(int id, availableCallbackFunc cb) {
+	return WRAP({
+		auto channel = getChannel(id);
+		if (cb)
+			channel->onOpen([id, cb]() { cb(getUserPointer(id)); });
+		else
+			channel->onOpen(nullptr);
+	});
+}
+
+int rtcReceiveMessage(int id, char *buffer, int *size) {
+	return WRAP({
+		auto channel = getChannel(id);
+
+		if (!buffer || !size)
+			throw std::invalid_argument("Unexpected null pointer");
+
+		if (auto message = channel->receive())
+			return std::visit( //
+			    overloaded{    //
+			               [&](const binary &b) {
+				               *size = std::min(*size, int(b.size()));
+				               auto data = reinterpret_cast<const char *>(b.data());
+				               std::copy(data, data + *size, buffer);
+				               return 1;
+			               },
+			               [&](const string &s) {
+				               int len = std::min(*size - 1, int(s.size()));
+				               if (len >= 0) {
+					               std::copy(s.data(), s.data() + len, buffer);
+					               buffer[len] = '\0';
+				               }
+				               *size = -(len + 1);
+				               return 1;
+			               }},
+			    *message);
+		else
+			return 0;
+	});
+}
+
+void rtcPreload() { rtc::Preload(); }
+void rtcCleanup() { rtc::Cleanup(); }

src/sctptransport.cpp

@@ -21,46 +21,86 @@
 #include <chrono>
 #include <exception>
 #include <iostream>
+#include <thread>
 #include <vector>
 
-#include <arpa/inet.h>
+#ifdef USE_JUICE
+#ifndef __APPLE__
+// libjuice enables Linux path MTU discovery or sets the DF flag
+#define USE_PMTUD 1
+#else
+// Setting the DF flag is not available on Mac OS
+#define USE_PMTUD 0
+#endif
+#else
+#ifdef __linux__
+// Linux UDP does path MTU discovery by default (setting DF and returning EMSGSIZE)
+// It should be safe to enable discovery for SCTP.
+#define USE_PMTUD 1
+#else
+// Otherwise assume fragmentation
+#define USE_PMTUD 0
+#endif
+#endif
+
+using namespace std::chrono_literals;
+using namespace std::chrono;
 
 using std::shared_ptr;
 
 namespace rtc {
 
-std::mutex SctpTransport::GlobalMutex;
+void SctpTransport::Init() {
-int SctpTransport::InstancesCount = 0;
-
-void SctpTransport::GlobalInit() {
-	std::unique_lock<std::mutex> lock(GlobalMutex);
-	if (InstancesCount++ == 0) {
 	usrsctp_init(0, &SctpTransport::WriteCallback, nullptr);
 	usrsctp_sysctl_set_sctp_ecn_enable(0);
-	}
+	usrsctp_sysctl_set_sctp_init_rtx_max_default(5);
+	usrsctp_sysctl_set_sctp_path_rtx_max_default(5);
+	usrsctp_sysctl_set_sctp_assoc_rtx_max_default(5);              // single path
+	usrsctp_sysctl_set_sctp_rto_min_default(1 * 1000);             // ms
+	usrsctp_sysctl_set_sctp_rto_max_default(10 * 1000);            // ms
+	usrsctp_sysctl_set_sctp_rto_initial_default(1 * 1000);         // ms
+	usrsctp_sysctl_set_sctp_init_rto_max_default(10 * 1000);       // ms
+	usrsctp_sysctl_set_sctp_heartbeat_interval_default(10 * 1000); // ms
+
+	usrsctp_sysctl_set_sctp_max_chunks_on_queue(10 * 1024);
+
+	// Change congestion control from the default TCP Reno (RFC 2581) to H-TCP
+	usrsctp_sysctl_set_sctp_default_cc_module(SCTP_CC_HTCP);
+
+	// Enable Non-Renegable Selective Acknowledgments (NR-SACKs)
+	usrsctp_sysctl_set_sctp_nrsack_enable(1);
+
+	// Increase the initial window size to 10 MTUs (RFC 6928)
+	usrsctp_sysctl_set_sctp_initial_cwnd(10);
+
+	// Reduce SACK delay from the default 200ms to 20ms
+	usrsctp_sysctl_set_sctp_delayed_sack_time_default(20); // ms
 }
 
-void SctpTransport::GlobalCleanup() {
+void SctpTransport::Cleanup() {
-	std::unique_lock<std::mutex> lock(GlobalMutex);
+	while (usrsctp_finish() != 0)
-	if (InstancesCount-- == 0) {
+		std::this_thread::sleep_for(100ms);
-		usrsctp_finish();
-	}
 }
 
-SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port, message_callback recv,
+SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port,
+                             message_callback recvCallback, amount_callback bufferedAmountCallback,
                              state_callback stateChangeCallback)
-    : Transport(lower), mPort(port), mState(State::Disconnected),
+    : Transport(lower, std::move(stateChangeCallback)), mPort(port),
-      mStateChangeCallback(std::move(stateChangeCallback)) {
+      mSendQueue(0, message_size_func), mBufferedAmountCallback(std::move(bufferedAmountCallback)) {
+	onRecv(recvCallback);
 
-	onRecv(recv);
+	PLOG_DEBUG << "Initializing SCTP transport";
 
-	GlobalInit();
 	usrsctp_register_address(this);
-	mSock = usrsctp_socket(AF_CONN, SOCK_STREAM, IPPROTO_SCTP, &SctpTransport::ReadCallback,
+	mSock = usrsctp_socket(AF_CONN, SOCK_STREAM, IPPROTO_SCTP, &SctpTransport::RecvCallback,
-	                       nullptr, 0, this);
+	                       &SctpTransport::SendCallback, 0, this);
 	if (!mSock)
-		throw std::runtime_error("Could not create usrsctp socket, errno=" + std::to_string(errno));
+		throw std::runtime_error("Could not create SCTP socket, errno=" + std::to_string(errno));
 
+	if (usrsctp_set_non_blocking(mSock, 1))
+		throw std::runtime_error("Unable to set non-blocking mode, errno=" + std::to_string(errno));
+
+	// SCTP must stop sending after the lower layer is shut down, so disable linger
 	struct linger sol = {};
 	sol.l_onoff = 1;
 	sol.l_linger = 0;
@@ -68,14 +108,6 @@ SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port, me
 		throw std::runtime_error("Could not set socket option SO_LINGER, errno=" +
 		                         std::to_string(errno));
 
-	struct sctp_paddrparams spp = {};
-	spp.spp_flags = SPP_PMTUD_DISABLE;
-	spp.spp_pathmtu = 1200; // Max safe value recommended by RFC 8261
-	                        // See https://tools.ietf.org/html/rfc8261#section-5
-	if (usrsctp_setsockopt(mSock, IPPROTO_SCTP, SCTP_PEER_ADDR_PARAMS, &spp, sizeof(spp)))
-		throw std::runtime_error("Could not set socket option SCTP_PEER_ADDR_PARAMS, errno=" +
-		                         std::to_string(errno));
-
 	struct sctp_assoc_value av = {};
 	av.assoc_id = SCTP_ALL_ASSOC;
 	av.assoc_value = 1;
@@ -83,17 +115,41 @@ SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port, me
 		throw std::runtime_error("Could not set socket option SCTP_ENABLE_STREAM_RESET, errno=" +
 		                         std::to_string(errno));
 
-	uint32_t nodelay = 1;
+	struct sctp_event se = {};
+	se.se_assoc_id = SCTP_ALL_ASSOC;
+	se.se_on = 1;
+	se.se_type = SCTP_ASSOC_CHANGE;
+	if (usrsctp_setsockopt(mSock, IPPROTO_SCTP, SCTP_EVENT, &se, sizeof(se)))
+		throw std::runtime_error("Could not subscribe to event SCTP_ASSOC_CHANGE, errno=" +
+		                         std::to_string(errno));
+	se.se_type = SCTP_SENDER_DRY_EVENT;
+	if (usrsctp_setsockopt(mSock, IPPROTO_SCTP, SCTP_EVENT, &se, sizeof(se)))
+		throw std::runtime_error("Could not subscribe to event SCTP_SENDER_DRY_EVENT, errno=" +
+		                         std::to_string(errno));
+	se.se_type = SCTP_STREAM_RESET_EVENT;
+	if (usrsctp_setsockopt(mSock, IPPROTO_SCTP, SCTP_EVENT, &se, sizeof(se)))
+		throw std::runtime_error("Could not subscribe to event SCTP_STREAM_RESET_EVENT, errno=" +
+		                         std::to_string(errno));
+
+	// The sender SHOULD disable the Nagle algorithm (see RFC1122) to minimize the latency.
+	// See https://tools.ietf.org/html/draft-ietf-rtcweb-data-channel-13#section-6.6
+	int nodelay = 1;
 	if (usrsctp_setsockopt(mSock, IPPROTO_SCTP, SCTP_NODELAY, &nodelay, sizeof(nodelay)))
 		throw std::runtime_error("Could not set socket option SCTP_NODELAY, errno=" +
 		                         std::to_string(errno));
 
-	struct sctp_event se = {};
+	struct sctp_paddrparams spp = {};
-	se.se_assoc_id = SCTP_ALL_ASSOC;
+#if USE_PMTUD
-	se.se_on = 1;
+	// Enabled SCTP path MTU discovery
-	se.se_type = SCTP_STREAM_RESET_EVENT;
+	spp.spp_flags = SPP_PMTUD_ENABLE;
-	if (usrsctp_setsockopt(mSock, IPPROTO_SCTP, SCTP_EVENT, &se, sizeof(se)))
+#else
-		throw std::runtime_error("Could not set socket option SCTP_EVENT, errno=" +
+	// Fall back to a safe MTU value.
+	spp.spp_flags = SPP_PMTUD_DISABLE;
+	spp.spp_pathmtu = 1200; // Max safe value recommended by RFC 8261
+	                        // See https://tools.ietf.org/html/rfc8261#section-5
+#endif
+	if (usrsctp_setsockopt(mSock, IPPROTO_SCTP, SCTP_PEER_ADDR_PARAMS, &spp, sizeof(spp)))
+		throw std::runtime_error("Could not set socket option SCTP_PEER_ADDR_PARAMS, errno=" +
 		                         std::to_string(errno));
 
 	// The IETF draft recommends the number of streams negotiated during SCTP association to be
@@ -105,6 +161,56 @@ SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port, me
 		throw std::runtime_error("Could not set socket option SCTP_INITMSG, errno=" +
 		                         std::to_string(errno));
 
+	// Prevent fragmented interleave of messages (i.e. level 0), see RFC 6458 8.1.20.
+	// Unless the user has set the fragmentation interleave level to 0, notifications
+	// may also be interleaved with partially delivered messages.
+	int level = 0;
+	if (usrsctp_setsockopt(mSock, IPPROTO_SCTP, SCTP_FRAGMENT_INTERLEAVE, &level, sizeof(level)))
+		throw std::runtime_error("Could not disable SCTP fragmented interleave, errno=" +
+		                         std::to_string(errno));
+
+	// The default send and receive window size of usrsctp is 256KiB, which is too small for
+	// realistic RTTs, therefore we increase it to 1MiB for better performance.
+	// See https://bugzilla.mozilla.org/show_bug.cgi?id=1051685
+	int bufferSize = 1024 * 1024;
+	if (usrsctp_setsockopt(mSock, SOL_SOCKET, SO_RCVBUF, &bufferSize, sizeof(bufferSize)))
+		throw std::runtime_error("Could not set SCTP recv buffer size, errno=" +
+		                         std::to_string(errno));
+	if (usrsctp_setsockopt(mSock, SOL_SOCKET, SO_SNDBUF, &bufferSize, sizeof(bufferSize)))
+		throw std::runtime_error("Could not set SCTP send buffer size, errno=" +
+		                         std::to_string(errno));
+
+	registerIncoming();
+	connect();
+}
+
+SctpTransport::~SctpTransport() {
+	stop();
+
+	if (mSock)
+		usrsctp_close(mSock);
+
+	usrsctp_deregister_address(this);
+}
+
+bool SctpTransport::stop() {
+	if (!Transport::stop())
+		return false;
+
+	mSendQueue.stop();
+	safeFlush();
+	shutdown();
+	onRecv(nullptr);
+	return true;
+}
+
+void SctpTransport::connect() {
+	if (!mSock)
+		return;
+
+	PLOG_DEBUG << "SCTP connect";
+	changeState(State::Connecting);
+
 	struct sockaddr_conn sconn = {};
 	sconn.sconn_family = AF_CONN;
 	sconn.sconn_port = htons(mPort);
@@ -116,33 +222,95 @@ SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port, me
 	if (usrsctp_bind(mSock, reinterpret_cast<struct sockaddr *>(&sconn), sizeof(sconn)))
 		throw std::runtime_error("Could not bind usrsctp socket, errno=" + std::to_string(errno));
 
-	mConnectThread = std::thread(&SctpTransport::runConnect, this);
+	// According to the IETF draft, both endpoints must initiate the SCTP association, in a
+	// simultaneous-open manner, irrelevent to the SDP setup role.
+	// See https://tools.ietf.org/html/draft-ietf-mmusic-sctp-sdp-26#section-9.3
+	int ret = usrsctp_connect(mSock, reinterpret_cast<struct sockaddr *>(&sconn), sizeof(sconn));
+	if (ret && errno != EINPROGRESS)
+		throw std::runtime_error("Connection attempt failed, errno=" + std::to_string(errno));
 }
 
-SctpTransport::~SctpTransport() {
+void SctpTransport::shutdown() {
-	mStopping = true;
+	if (!mSock)
-	mConnectCondition.notify_all();
+		return;
-	if (mConnectThread.joinable())
-		mConnectThread.join();
 
-	if (mSock) {
+	PLOG_DEBUG << "SCTP shutdown";
-		usrsctp_shutdown(mSock, SHUT_RDWR);
+
-		usrsctp_close(mSock);
+	if (usrsctp_shutdown(mSock, SHUT_RDWR) != 0 && errno != ENOTCONN) {
+		PLOG_WARNING << "SCTP shutdown failed, errno=" << errno;
 	}
 
-	usrsctp_deregister_address(this);
+	// close() abort the connection when linger is disabled, call it now
-	GlobalCleanup();
+	usrsctp_close(mSock);
+	mSock = nullptr;
+
+	PLOG_INFO << "SCTP disconnected";
+	changeState(State::Disconnected);
+	mWrittenCondition.notify_all();
 }
 
-SctpTransport::State SctpTransport::state() const { return mState; }
-
 bool SctpTransport::send(message_ptr message) {
+	std::lock_guard lock(mSendMutex);
+
 	if (!message)
+		return mSendQueue.empty();
+
+	PLOG_VERBOSE << "Send size=" << message->size();
+
+	// If nothing is pending, try to send directly
+	if (mSendQueue.empty() && trySendMessage(message))
+		return true;
+
+	mSendQueue.push(message);
+	updateBufferedAmount(message->stream, message_size_func(message));
 	return false;
+}
 
-	const Reliability reliability = message->reliability ? *message->reliability : Reliability();
+void SctpTransport::close(unsigned int stream) {
+	send(make_message(0, Message::Reset, uint16_t(stream)));
+}
 
-	struct sctp_sendv_spa spa = {};
+void SctpTransport::flush() {
+	std::lock_guard lock(mSendMutex);
+	trySendQueue();
+}
+
+void SctpTransport::incoming(message_ptr message) {
+	// There could be a race condition here where we receive the remote INIT before the local one is
+	// sent, which would result in the connection being aborted. Therefore, we need to wait for data
+	// to be sent on our side (i.e. the local INIT) before proceeding.
+	if (!mWrittenOnce) { // test the atomic boolean is not set first to prevent a lock contention
+		std::unique_lock lock(mWriteMutex);
+		mWrittenCondition.wait(lock, [&]() { return mWrittenOnce || state() != State::Connected; });
+	}
+
+	if (!message) {
+		PLOG_INFO << "SCTP disconnected";
+		changeState(State::Disconnected);
+		recv(nullptr);
+		return;
+	}
+
+	PLOG_VERBOSE << "Incoming size=" << message->size();
+	usrsctp_conninput(this, message->data(), message->size(), 0);
+}
+
+bool SctpTransport::trySendQueue() {
+	// Requires mSendMutex to be locked
+	while (auto next = mSendQueue.peek()) {
+		auto message = *next;
+		if (!trySendMessage(message))
+			return false;
+		mSendQueue.pop();
+		updateBufferedAmount(message->stream, -message_size_func(message));
+	}
+	return true;
+}
+
+bool SctpTransport::trySendMessage(message_ptr message) {
+	// Requires mSendMutex to be locked
+	if (!mSock || state() != State::Connected)
+		return false;
 
 	uint32_t ppid;
 	switch (message->type) {
@@ -152,23 +320,37 @@ bool SctpTransport::send(message_ptr message) {
 	case Message::Binary:
 		ppid = !message->empty() ? PPID_BINARY : PPID_BINARY_EMPTY;
 		break;
-	default:
+	case Message::Control:
 		ppid = PPID_CONTROL;
 		break;
+	case Message::Reset:
+		sendReset(message->stream);
+		return true;
+	default:
+		// Ignore
+		return true;
 	}
 
+	PLOG_VERBOSE << "SCTP try send size=" << message->size();
+
+	// TODO: Implement SCTP ndata specification draft when supported everywhere
+	// See https://tools.ietf.org/html/draft-ietf-tsvwg-sctp-ndata-08
+
+	const Reliability reliability = message->reliability ? *message->reliability : Reliability();
+
+	struct sctp_sendv_spa spa = {};
+
 	// set sndinfo
 	spa.sendv_flags |= SCTP_SEND_SNDINFO_VALID;
 	spa.sendv_sndinfo.snd_sid = uint16_t(message->stream);
 	spa.sendv_sndinfo.snd_ppid = htonl(ppid);
-	spa.sendv_sndinfo.snd_flags |= SCTP_EOR;
+	spa.sendv_sndinfo.snd_flags |= SCTP_EOR; // implicit here
 
 	// set prinfo
 	spa.sendv_flags |= SCTP_SEND_PRINFO_VALID;
 	if (reliability.unordered)
 		spa.sendv_sndinfo.snd_flags |= SCTP_UNORDERED;
 
-	using std::chrono::milliseconds;
 	switch (reliability.type) {
 	case Reliability::TYPE_PARTIAL_RELIABLE_REXMIT:
 		spa.sendv_flags |= SCTP_SEND_PRINFO_VALID;
@@ -185,153 +367,260 @@ bool SctpTransport::send(message_ptr message) {
 		break;
 	}
 
+	ssize_t ret;
 	if (!message->empty()) {
-		return usrsctp_sendv(mSock, message->data(), message->size(), nullptr, 0, &spa, sizeof(spa),
+		ret = usrsctp_sendv(mSock, message->data(), message->size(), nullptr, 0, &spa, sizeof(spa),
-		                     SCTP_SENDV_SPA, 0) > 0;
+		                    SCTP_SENDV_SPA, 0);
 	} else {
 		const char zero = 0;
-		return usrsctp_sendv(mSock, &zero, 1, nullptr, 0, &spa, sizeof(spa), SCTP_SENDV_SPA, 0) > 0;
+		ret = usrsctp_sendv(mSock, &zero, 1, nullptr, 0, &spa, sizeof(spa), SCTP_SENDV_SPA, 0);
 	}
+
+	if (ret < 0) {
+		if (errno == EWOULDBLOCK || errno == EAGAIN) {
+			PLOG_VERBOSE << "SCTP sending not possible";
+			return false;
+		}
+
+		PLOG_ERROR << "SCTP sending failed, errno=" << errno;
+		throw std::runtime_error("Sending failed, errno=" + std::to_string(errno));
+	}
+
+	PLOG_VERBOSE << "SCTP sent size=" << message->size();
+	if (message->type == Message::Type::Binary || message->type == Message::Type::String)
+		mBytesSent += message->size();
+	return true;
 }
 
-void SctpTransport::reset(unsigned int stream) {
+void SctpTransport::updateBufferedAmount(uint16_t streamId, long delta) {
+	// Requires mSendMutex to be locked
+	auto it = mBufferedAmount.insert(std::make_pair(streamId, 0)).first;
+	size_t amount = size_t(std::max(long(it->second) + delta, long(0)));
+	if (amount == 0)
+		mBufferedAmount.erase(it);
+	else
+		it->second = amount;
+
+	mSendMutex.unlock();
+	try {
+		mBufferedAmountCallback(streamId, amount);
+	} catch (const std::exception &e) {
+		PLOG_WARNING << "SCTP buffered amount callback: " << e.what();
+	}
+	mSendMutex.lock();
+}
+
+void SctpTransport::sendReset(uint16_t streamId) {
+	// Requires mSendMutex to be locked
+	if (!mSock || state() != State::Connected)
+		return;
+
+	PLOG_DEBUG << "SCTP resetting stream " << streamId;
+
 	using srs_t = struct sctp_reset_streams;
 	const size_t len = sizeof(srs_t) + sizeof(uint16_t);
 	byte buffer[len] = {};
 	srs_t &srs = *reinterpret_cast<srs_t *>(buffer);
 	srs.srs_flags = SCTP_STREAM_RESET_OUTGOING;
 	srs.srs_number_streams = 1;
-	srs.srs_stream_list[0] = uint16_t(stream);
+	srs.srs_stream_list[0] = streamId;
-	usrsctp_setsockopt(mSock, IPPROTO_SCTP, SCTP_RESET_STREAMS, &srs, len);
-}
 
-void SctpTransport::incoming(message_ptr message) {
+	mWritten = false;
-	if (!message) {
+	if (usrsctp_setsockopt(mSock, IPPROTO_SCTP, SCTP_RESET_STREAMS, &srs, len) == 0) {
-		changeState(State::Disconnected);
+		std::unique_lock lock(mWriteMutex); // locking before setsockopt might deadlock usrsctp...
-		recv(nullptr);
+		mWrittenCondition.wait_for(lock, 1000ms,
-		return;
+		                           [&]() { return mWritten || state() != State::Connected; });
+	} else if (errno == EINVAL) {
+		PLOG_VERBOSE << "SCTP stream " << streamId << " already reset";
+	} else {
+		PLOG_WARNING << "SCTP reset stream " << streamId << " failed, errno=" << errno;
 	}
-
-	// There could be a race condition here where we receive the remote INIT before the thread in
-	// usrsctp_connect sends the local one, which would result in the connection being aborted.
-	// Therefore, we need to wait for data to be sent on our side (i.e. the local INIT) before
-	// proceeding.
-	if (!mConnectDataSent) {
-		std::unique_lock<std::mutex> lock(mConnectMutex);
-		mConnectCondition.wait(lock, [this] { return mConnectDataSent || mStopping; });
-	}
-
-	if (!mStopping)
-		usrsctp_conninput(this, message->data(), message->size(), 0);
 }
 
-void SctpTransport::changeState(State state) {
+bool SctpTransport::safeFlush() {
-	mState = state;
-	mStateChangeCallback(state);
-}
-
-void SctpTransport::runConnect() {
 	try {
-		changeState(State::Connecting);
+		flush();
-
+		return true;
-		struct sockaddr_conn sconn = {};
-		sconn.sconn_family = AF_CONN;
-		sconn.sconn_port = htons(mPort);
-		sconn.sconn_addr = this;
-#ifdef HAVE_SCONN_LEN
-		sconn.sconn_len = sizeof(sconn);
-#endif
-
-		// According to the IETF draft, both endpoints must initiate the SCTP association, in a
-		// simultaneous-open manner, irrelevent to the SDP setup role.
-		// See https://tools.ietf.org/html/draft-ietf-mmusic-sctp-sdp-26#section-9.3
-		if (usrsctp_connect(mSock, reinterpret_cast<struct sockaddr *>(&sconn), sizeof(sconn)) !=
-		    0) {
-			std::cerr << "SCTP connection failed, errno=" << errno << std::endl;
-			changeState(State::Failed);
-			mStopping = true;
-			return;
-		}
-
-		if (!mStopping)
-			changeState(State::Connected);
 
 	} catch (const std::exception &e) {
-		std::cerr << "SCTP connect: " << e.what() << std::endl;
+		PLOG_WARNING << "SCTP flush: " << e.what();
+		return false;
 	}
 }
 
-int SctpTransport::handleWrite(void *data, size_t len, uint8_t tos, uint8_t set_df) {
+int SctpTransport::handleRecv(struct socket *sock, union sctp_sockstore addr, const byte *data,
-	byte *b = reinterpret_cast<byte *>(data);
+                              size_t len, struct sctp_rcvinfo info, int flags) {
-	outgoing(make_message(b, b + len));
+	try {
+		PLOG_VERBOSE << "Handle recv, len=" << len;
+		if (!len)
+			return -1;
 
-	if (!mConnectDataSent) {
+		// This is valid because SCTP_FRAGMENT_INTERLEAVE is set to level 0
-		std::unique_lock<std::mutex> lock(mConnectMutex);
+		// so partial messages and notifications may not be interleaved.
-		mConnectDataSent = true;
+		if (flags & MSG_EOR) {
-		mConnectCondition.notify_all();
+			if (!mPartialRecv.empty()) {
+				mPartialRecv.insert(mPartialRecv.end(), data, data + len);
+				data = mPartialRecv.data();
+				len = mPartialRecv.size();
+			}
+			// Message/Notification is complete, process it
+			if (flags & MSG_NOTIFICATION)
+				processNotification(reinterpret_cast<const union sctp_notification *>(data), len);
+			else
+				processData(data, len, info.rcv_sid, PayloadId(htonl(info.rcv_ppid)));
+
+			mPartialRecv.clear();
+		} else {
+			// Message/Notification is not complete
+			mPartialRecv.insert(mPartialRecv.end(), data, data + len);
+		}
+	} catch (const std::exception &e) {
+		PLOG_ERROR << "SCTP recv: " << e.what();
+		return -1;
 	}
 	return 0; // success
 }
 
-int SctpTransport::process(struct socket *sock, union sctp_sockstore addr, void *data, size_t len,
+int SctpTransport::handleSend(size_t free) {
-                           struct sctp_rcvinfo info, int flags) {
+	PLOG_VERBOSE << "Handle send, free=" << free;
-	if (flags & MSG_NOTIFICATION) {
+	return safeFlush() ? 0 : -1;
-		processNotification((union sctp_notification *)data, len);
+}
-	} else {
+
-		processData((const byte *)data, len, info.rcv_sid, PayloadId(htonl(info.rcv_ppid)));
+int SctpTransport::handleWrite(byte *data, size_t len, uint8_t tos, uint8_t set_df) {
+	try {
+		PLOG_VERBOSE << "Handle write, len=" << len;
+
+		std::unique_lock lock(mWriteMutex);
+		if (!outgoing(make_message(data, data + len)))
+			return -1;
+
+		mWritten = true;
+		mWrittenOnce = true;
+		mWrittenCondition.notify_all();
+
+	} catch (const std::exception &e) {
+		PLOG_ERROR << "SCTP write: " << e.what();
+		return -1;
 	}
-	free(data);
+	return 0; // success
-	return 0;
 }
 
 void SctpTransport::processData(const byte *data, size_t len, uint16_t sid, PayloadId ppid) {
-	Message::Type type;
+	PLOG_VERBOSE << "Process data, len=" << len;
+
+	// The usage of the PPIDs "WebRTC String Partial" and "WebRTC Binary Partial" is deprecated.
+	// See https://tools.ietf.org/html/draft-ietf-rtcweb-data-channel-13#section-6.6
+	// We handle them at reception for compatibility reasons but should never send them.
 	switch (ppid) {
-	case PPID_STRING:
-		type = Message::String;
-		break;
-	case PPID_STRING_EMPTY:
-		type = Message::String;
-		len = 0;
-		break;
-	case PPID_BINARY:
-		type = Message::Binary;
-		break;
-	case PPID_BINARY_EMPTY:
-		type = Message::Binary;
-		len = 0;
-		break;
 	case PPID_CONTROL:
-		type = Message::Control;
+		recv(make_message(data, data + len, Message::Control, sid));
 		break;
+
+	case PPID_STRING_PARTIAL: // deprecated
+		mPartialStringData.insert(mPartialStringData.end(), data, data + len);
+		break;
+
+	case PPID_STRING:
+		if (mPartialStringData.empty()) {
+			mBytesReceived += len;
+			recv(make_message(data, data + len, Message::String, sid));
+		} else {
+			mPartialStringData.insert(mPartialStringData.end(), data, data + len);
+			mBytesReceived += mPartialStringData.size();
+			recv(make_message(mPartialStringData.begin(), mPartialStringData.end(), Message::String,
+			                  sid));
+			mPartialStringData.clear();
+		}
+		break;
+
+	case PPID_STRING_EMPTY:
+		// This only accounts for when the partial data is empty
+		recv(make_message(mPartialStringData.begin(), mPartialStringData.end(), Message::String,
+		                  sid));
+		mPartialStringData.clear();
+		break;
+
+	case PPID_BINARY_PARTIAL: // deprecated
+		mPartialBinaryData.insert(mPartialBinaryData.end(), data, data + len);
+		break;
+
+	case PPID_BINARY:
+		if (mPartialBinaryData.empty()) {
+			mBytesReceived += len;
+			recv(make_message(data, data + len, Message::Binary, sid));
+		} else {
+			mPartialBinaryData.insert(mPartialBinaryData.end(), data, data + len);
+			mBytesReceived += mPartialStringData.size();
+			recv(make_message(mPartialBinaryData.begin(), mPartialBinaryData.end(), Message::Binary,
+			                  sid));
+			mPartialBinaryData.clear();
+		}
+		break;
+
+	case PPID_BINARY_EMPTY:
+		// This only accounts for when the partial data is empty
+		recv(make_message(mPartialBinaryData.begin(), mPartialBinaryData.end(), Message::Binary,
+		                  sid));
+		mPartialBinaryData.clear();
+		break;
+
 	default:
 		// Unknown
-		std::cerr << "Unknown PPID: " << uint32_t(ppid) << std::endl;
+		PLOG_WARNING << "Unknown PPID: " << uint32_t(ppid);
 		return;
 	}
-	recv(make_message(data, data + len, type, sid));
 }
 
 void SctpTransport::processNotification(const union sctp_notification *notify, size_t len) {
-	if (len != size_t(notify->sn_header.sn_length))
+	if (len != size_t(notify->sn_header.sn_length)) {
+		PLOG_WARNING << "Invalid notification length";
 		return;
+	}
+
+	auto type = notify->sn_header.sn_type;
+	PLOG_VERBOSE << "Process notification, type=" << type;
+
+	switch (type) {
+	case SCTP_ASSOC_CHANGE: {
+		const struct sctp_assoc_change &assoc_change = notify->sn_assoc_change;
+		if (assoc_change.sac_state == SCTP_COMM_UP) {
+			PLOG_INFO << "SCTP connected";
+			changeState(State::Connected);
+		} else {
+			if (state() == State::Connecting) {
+				PLOG_ERROR << "SCTP connection failed";
+				changeState(State::Failed);
+			} else {
+				PLOG_INFO << "SCTP disconnected";
+				changeState(State::Disconnected);
+			}
+			mWrittenCondition.notify_all();
+		}
+		break;
+	}
+
+	case SCTP_SENDER_DRY_EVENT: {
+		// It not should be necessary since the send callback should have been called already,
+		// but to be sure, let's try to send now.
+		safeFlush();
+		break;
+	}
 
-	switch (notify->sn_header.sn_type) {
 	case SCTP_STREAM_RESET_EVENT: {
-		const struct sctp_stream_reset_event *reset_event = &notify->sn_strreset_event;
+		const struct sctp_stream_reset_event &reset_event = notify->sn_strreset_event;
-		const int count = (reset_event->strreset_length - sizeof(*reset_event)) / sizeof(uint16_t);
+		const int count = (reset_event.strreset_length - sizeof(reset_event)) / sizeof(uint16_t);
+		const uint16_t flags = reset_event.strreset_flags;
 
-		if (reset_event->strreset_flags & SCTP_STREAM_RESET_INCOMING_SSN) {
+		if (flags & SCTP_STREAM_RESET_OUTGOING_SSN) {
 			for (int i = 0; i < count; ++i) {
-				uint16_t streamId = reset_event->strreset_stream_list[i];
+				uint16_t streamId = reset_event.strreset_stream_list[i];
-				reset(streamId);
+				close(streamId);
 			}
 		}
-
+		if (flags & SCTP_STREAM_RESET_INCOMING_SSN) {
-		if (reset_event->strreset_flags & SCTP_STREAM_RESET_OUTGOING_SSN) {
 			const byte dataChannelCloseMessage{0x04};
 			for (int i = 0; i < count; ++i) {
-				uint16_t streamId = reset_event->strreset_stream_list[i];
+				uint16_t streamId = reset_event.strreset_stream_list[i];
 				recv(make_message(&dataChannelCloseMessage, &dataChannelCloseMessage + 1,
 				                  Message::Control, streamId));
 			}
@@ -344,16 +633,51 @@ void SctpTransport::processNotification(const union sctp_notification *notify, s
 		break;
 	}
 }
-int SctpTransport::WriteCallback(void *sctp_ptr, void *data, size_t len, uint8_t tos,
+
-                                 uint8_t set_df) {
+void SctpTransport::clearStats() {
-	return static_cast<SctpTransport *>(sctp_ptr)->handleWrite(data, len, tos, set_df);
+	mBytesReceived = 0;
+	mBytesSent = 0;
 }
 
-int SctpTransport::ReadCallback(struct socket *sock, union sctp_sockstore addr, void *data,
+size_t SctpTransport::bytesSent() { return mBytesSent; }
-                                size_t len, struct sctp_rcvinfo recv_info, int flags,
+
-                                void *user_data) {
+size_t SctpTransport::bytesReceived() { return mBytesReceived; }
-	return static_cast<SctpTransport *>(user_data)->process(sock, addr, data, len, recv_info,
+
-	                                                        flags);
+std::optional<milliseconds> SctpTransport::rtt() {
+	if (!mSock || state() != State::Connected)
+		return nullopt;
+
+	struct sctp_status status = {};
+	socklen_t len = sizeof(status);
+	if (usrsctp_getsockopt(mSock, IPPROTO_SCTP, SCTP_STATUS, &status, &len)) {
+		PLOG_WARNING << "Could not read SCTP_STATUS";
+		return nullopt;
+	}
+	return milliseconds(status.sstat_primary.spinfo_srtt);
+}
+
+int SctpTransport::RecvCallback(struct socket *sock, union sctp_sockstore addr, void *data,
+                                size_t len, struct sctp_rcvinfo recv_info, int flags, void *ptr) {
+	int ret = static_cast<SctpTransport *>(ptr)->handleRecv(
+	    sock, addr, static_cast<const byte *>(data), len, recv_info, flags);
+	free(data);
+	return ret;
+}
+
+int SctpTransport::SendCallback(struct socket *sock, uint32_t sb_free) {
+	struct sctp_paddrinfo paddrinfo = {};
+	socklen_t len = sizeof(paddrinfo);
+	if (usrsctp_getsockopt(sock, IPPROTO_SCTP, SCTP_GET_PEER_ADDR_INFO, &paddrinfo, &len))
+		return -1;
+
+	auto sconn = reinterpret_cast<struct sockaddr_conn *>(&paddrinfo.spinfo_address);
+	void *ptr = sconn->sconn_addr;
+	return static_cast<SctpTransport *>(ptr)->handleSend(size_t(sb_free));
+}
+
+int SctpTransport::WriteCallback(void *ptr, void *data, size_t len, uint8_t tos, uint8_t set_df) {
+	return static_cast<SctpTransport *>(ptr)->handleWrite(static_cast<byte *>(data), len, tos,
+	                                                      set_df);
 }
 
 } // namespace rtc

src/sctptransport.hpp

@@ -21,77 +21,93 @@
 
 #include "include.hpp"
 #include "peerconnection.hpp"
+#include "queue.hpp"
 #include "transport.hpp"
 
 #include <condition_variable>
 #include <functional>
+#include <map>
 #include <mutex>
-#include <thread>
 
-#include <sys/socket.h>
+#include "usrsctp.h"
-#include <sys/types.h>
-#include <usrsctp.h>
 
 namespace rtc {
 
 class SctpTransport : public Transport {
 public:
-	enum class State { Disconnected, Connecting, Connected, Failed };
+	static void Init();
+	static void Cleanup();
 
-	using state_callback = std::function<void(State state)>;
+	using amount_callback = std::function<void(uint16_t streamId, size_t amount)>;
 
-	SctpTransport(std::shared_ptr<Transport> lower, uint16_t port, message_callback recv,
+	SctpTransport(std::shared_ptr<Transport> lower, uint16_t port, message_callback recvCallback,
-	              state_callback stateChangeCallback);
+	              amount_callback bufferedAmountCallback, state_callback stateChangeCallback);
 	~SctpTransport();
 
-	State state() const;
+	bool stop() override;
+	bool send(message_ptr message) override; // false if buffered
+	void close(unsigned int stream);
+	void flush();
 
-	bool send(message_ptr message);
+	// Stats
-	void reset(unsigned int stream);
+	void clearStats();
+	size_t bytesSent();
+	size_t bytesReceived();
+	std::optional<std::chrono::milliseconds> rtt();
 
 private:
+	// Order seems wrong but these are the actual values
+	// See https://tools.ietf.org/html/draft-ietf-rtcweb-data-channel-13#section-8
 	enum PayloadId : uint32_t {
 		PPID_CONTROL = 50,
 		PPID_STRING = 51,
+		PPID_BINARY_PARTIAL = 52,
 		PPID_BINARY = 53,
+		PPID_STRING_PARTIAL = 54,
 		PPID_STRING_EMPTY = 56,
 		PPID_BINARY_EMPTY = 57
 	};
 
-	void incoming(message_ptr message);
+	void connect();
-	void changeState(State state);
+	void shutdown();
-	void runConnect();
+	void incoming(message_ptr message) override;
 
-	int handleWrite(void *data, size_t len, uint8_t tos, uint8_t set_df);
+	bool trySendQueue();
+	bool trySendMessage(message_ptr message);
+	void updateBufferedAmount(uint16_t streamId, long delta);
+	void sendReset(uint16_t streamId);
+	bool safeFlush();
 
-	int process(struct socket *sock, union sctp_sockstore addr, void *data, size_t len,
+	int handleRecv(struct socket *sock, union sctp_sockstore addr, const byte *data, size_t len,
 	               struct sctp_rcvinfo recv_info, int flags);
+	int handleSend(size_t free);
+	int handleWrite(byte *data, size_t len, uint8_t tos, uint8_t set_df);
 
 	void processData(const byte *data, size_t len, uint16_t streamId, PayloadId ppid);
 	void processNotification(const union sctp_notification *notify, size_t len);
 
+	const uint16_t mPort;
 	struct socket *mSock;
-	uint16_t mPort;
 
-	std::thread mConnectThread;
+	std::mutex mSendMutex;
-	std::mutex mConnectMutex;
+	Queue<message_ptr> mSendQueue;
-	std::condition_variable mConnectCondition;
+	std::map<uint16_t, size_t> mBufferedAmount;
-	std::atomic<bool> mConnectDataSent = false;
+	amount_callback mBufferedAmountCallback;
-	std::atomic<bool> mStopping = false;
 
-	std::atomic<State> mState;
+	std::mutex mWriteMutex;
+	std::condition_variable mWrittenCondition;
+	std::atomic<bool> mWritten = false; // written outside lock
+	std::atomic<bool> mWrittenOnce = false; // same
 
-	state_callback mStateChangeCallback;
+	binary mPartialRecv, mPartialStringData, mPartialBinaryData;
 
-	static int WriteCallback(void *sctp_ptr, void *data, size_t len, uint8_t tos, uint8_t set_df);
+	// Stats
-	static int ReadCallback(struct socket *sock, union sctp_sockstore addr, void *data, size_t len,
+	std::atomic<size_t> mBytesSent = 0, mBytesReceived = 0;
+
+	static int RecvCallback(struct socket *sock, union sctp_sockstore addr, void *data, size_t len,
 	                        struct sctp_rcvinfo recv_info, int flags, void *user_data);
-
+	static int SendCallback(struct socket *sock, uint32_t sb_free);
-	void GlobalInit();
+	static int WriteCallback(void *sctp_ptr, void *data, size_t len, uint8_t tos, uint8_t set_df);
-	void GlobalCleanup();
-
-	static std::mutex GlobalMutex;
-	static int InstancesCount;
 };
 
 } // namespace rtc

src/tcptransport.cpp

@@ -0,0 +1,378 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "tcptransport.hpp"
+
+#if RTC_ENABLE_WEBSOCKET
+
+#include <exception>
+#ifndef _WIN32
+#include <fcntl.h>
+#include <unistd.h>
+#endif
+
+namespace rtc {
+
+using std::to_string;
+
+SelectInterrupter::SelectInterrupter() {
+#ifndef _WIN32
+	int pipefd[2];
+	if (::pipe(pipefd) != 0)
+		throw std::runtime_error("Failed to create pipe");
+	::fcntl(pipefd[0], F_SETFL, O_NONBLOCK);
+	::fcntl(pipefd[1], F_SETFL, O_NONBLOCK);
+	mPipeOut = pipefd[0]; // read
+	mPipeIn = pipefd[1];  // write
+#endif
+}
+
+SelectInterrupter::~SelectInterrupter() {
+	std::lock_guard lock(mMutex);
+#ifdef _WIN32
+	if (mDummySock != INVALID_SOCKET)
+		::closesocket(mDummySock);
+#else
+	::close(mPipeIn);
+	::close(mPipeOut);
+#endif
+}
+
+int SelectInterrupter::prepare(fd_set &readfds, fd_set &writefds) {
+	std::lock_guard lock(mMutex);
+#ifdef _WIN32
+	if (mDummySock == INVALID_SOCKET)
+		mDummySock = ::socket(AF_INET, SOCK_DGRAM, 0);
+	FD_SET(mDummySock, &readfds);
+	return SOCKET_TO_INT(mDummySock) + 1;
+#else
+	int ret;
+	do {
+		char dummy;
+		ret = ::read(mPipeIn, &dummy, 1);
+	} while (ret > 0);
+	FD_SET(mPipeIn, &readfds);
+	return mPipeIn + 1;
+#endif
+}
+
+void SelectInterrupter::interrupt() {
+	std::lock_guard lock(mMutex);
+#ifdef _WIN32
+	if (mDummySock != INVALID_SOCKET) {
+		::closesocket(mDummySock);
+		mDummySock = INVALID_SOCKET;
+	}
+#else
+	char dummy = 0;
+	::write(mPipeOut, &dummy, 1);
+#endif
+}
+
+TcpTransport::TcpTransport(const string &hostname, const string &service, state_callback callback)
+    : Transport(nullptr, std::move(callback)), mHostname(hostname), mService(service) {
+
+	PLOG_DEBUG << "Initializing TCP transport";
+	mThread = std::thread(&TcpTransport::runLoop, this);
+}
+
+TcpTransport::~TcpTransport() {
+	stop();
+}
+
+bool TcpTransport::stop() {
+	if (!Transport::stop())
+		return false;
+
+	PLOG_DEBUG << "Waiting for TCP recv thread";
+	close();
+	mThread.join();
+	return true;
+}
+
+bool TcpTransport::send(message_ptr message) {
+	if (state() != State::Connected)
+		return false;
+
+	if (!message)
+		return mSendQueue.empty();
+
+	PLOG_VERBOSE << "Send size=" << (message ? message->size() : 0);
+	return outgoing(message);
+}
+
+void TcpTransport::incoming(message_ptr message) {
+	if (!message)
+		return;
+
+	PLOG_VERBOSE << "Incoming size=" << message->size();
+	recv(message);
+}
+
+bool TcpTransport::outgoing(message_ptr message) {
+	// If nothing is pending, try to send directly
+	// It's safe because if the queue is empty, the thread is not sending
+	if (mSendQueue.empty() && trySendMessage(message))
+		return true;
+
+	mSendQueue.push(message);
+	interruptSelect(); // so the thread waits for writability
+	return false;
+}
+
+void TcpTransport::connect(const string &hostname, const string &service) {
+	PLOG_DEBUG << "Connecting to " << hostname << ":" << service;
+
+	struct addrinfo hints = {};
+	hints.ai_family = AF_UNSPEC;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_protocol = IPPROTO_TCP;
+	hints.ai_flags = AI_ADDRCONFIG;
+
+	struct addrinfo *result = nullptr;
+	if (getaddrinfo(hostname.c_str(), service.c_str(), &hints, &result))
+		throw std::runtime_error("Resolution failed for \"" + hostname + ":" + service + "\"");
+
+	for (auto p = result; p; p = p->ai_next) {
+		try {
+			connect(p->ai_addr, p->ai_addrlen);
+
+			PLOG_INFO << "Connected to " << hostname << ":" << service;
+			freeaddrinfo(result);
+			return;
+
+		} catch (const std::runtime_error &e) {
+			if (p->ai_next) {
+				PLOG_DEBUG << e.what();
+			} else {
+				PLOG_WARNING << e.what();
+			}
+		}
+	}
+
+	freeaddrinfo(result);
+
+	std::ostringstream msg;
+	msg << "Connection to " << hostname << ":" << service << " failed";
+	throw std::runtime_error(msg.str());
+}
+
+void TcpTransport::connect(const sockaddr *addr, socklen_t addrlen) {
+	try {
+		char node[MAX_NUMERICNODE_LEN];
+		char serv[MAX_NUMERICSERV_LEN];
+		if (getnameinfo(addr, addrlen, node, MAX_NUMERICNODE_LEN, serv, MAX_NUMERICSERV_LEN,
+		                NI_NUMERICHOST | NI_NUMERICSERV) == 0) {
+			PLOG_DEBUG << "Trying address " << node << ":" << serv;
+		}
+
+		PLOG_VERBOSE << "Creating TCP socket";
+
+		// Create socket
+		mSock = ::socket(addr->sa_family, SOCK_STREAM, IPPROTO_TCP);
+		if (mSock == INVALID_SOCKET)
+			throw std::runtime_error("TCP socket creation failed");
+
+		ctl_t b = 1;
+		if (::ioctlsocket(mSock, FIONBIO, &b) < 0)
+			throw std::runtime_error("Failed to set socket non-blocking mode");
+
+#ifdef __APPLE__
+		// MacOS lacks MSG_NOSIGNAL and requires SO_NOSIGPIPE instead
+		int opt = 1;
+		if (::setsockopt(mSock, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof(opt)) < 0)
+			throw std::runtime_error("Failed to disable SIGPIPE for socket");
+#endif
+
+		// Initiate connection
+		int ret = ::connect(mSock, addr, addrlen);
+		if (ret < 0 && errno != EINPROGRESS) {
+			std::ostringstream msg;
+			msg << "TCP connection to " << node << ":" << serv << " failed, errno=" << sockerrno;
+			throw std::runtime_error(msg.str());
+		}
+
+		fd_set writefds;
+		FD_ZERO(&writefds);
+		FD_SET(mSock, &writefds);
+		struct timeval tv;
+		tv.tv_sec = 10; // TODO
+		tv.tv_usec = 0;
+		ret = ::select(SOCKET_TO_INT(mSock) + 1, NULL, &writefds, NULL, &tv);
+
+		if (ret < 0)
+			throw std::runtime_error("Failed to wait for socket connection");
+
+		if (ret == 0) {
+			std::ostringstream msg;
+			msg << "TCP connection to " << node << ":" << serv << " timed out";
+			throw std::runtime_error(msg.str());
+		}
+
+		int error = 0;
+		socklen_t errorlen = sizeof(error);
+		if (::getsockopt(mSock, SOL_SOCKET, SO_ERROR, (char *)&error, &errorlen) != 0)
+			throw std::runtime_error("Failed to get socket error code");
+
+		if (error != 0) {
+			std::ostringstream msg;
+			msg << "TCP connection to " << node << ":" << serv << " failed, errno=" << error;
+			throw std::runtime_error(msg.str());
+		}
+
+		PLOG_DEBUG << "TCP connection to " << node << ":" << serv << " succeeded";
+
+	} catch (...) {
+		if (mSock != INVALID_SOCKET) {
+			::closesocket(mSock);
+			mSock = INVALID_SOCKET;
+		}
+		throw;
+	}
+}
+
+void TcpTransport::close() {
+	if (mSock != INVALID_SOCKET) {
+		PLOG_DEBUG << "Closing TCP socket";
+		::closesocket(mSock);
+		mSock = INVALID_SOCKET;
+	}
+	changeState(State::Disconnected);
+}
+
+bool TcpTransport::trySendQueue() {
+	while (auto next = mSendQueue.peek()) {
+		auto message = *next;
+		if (!trySendMessage(message)) {
+			mSendQueue.exchange(message);
+			return false;
+		}
+		mSendQueue.pop();
+	}
+	return true;
+}
+
+bool TcpTransport::trySendMessage(message_ptr &message) {
+	auto data = reinterpret_cast<const char *>(message->data());
+	auto size = message->size();
+	while (size) {
+#if defined(__APPLE__) or defined(_WIN32)
+		int flags = 0;
+#else
+		int flags = MSG_NOSIGNAL;
+#endif
+		int len = ::send(mSock, data, size, flags);
+		if (len < 0) {
+			if (errno == EAGAIN || errno == EWOULDBLOCK) {
+				message = make_message(message->end() - size, message->end());
+				return false;
+			} else {
+				throw std::runtime_error("Connection lost, errno=" + to_string(sockerrno));
+			}
+		}
+
+		data += len;
+		size -= len;
+	}
+	message = nullptr;
+	return true;
+}
+
+void TcpTransport::runLoop() {
+	const size_t bufferSize = 4096;
+
+	// Connect
+	try {
+		changeState(State::Connecting);
+		connect(mHostname, mService);
+
+	} catch (const std::exception &e) {
+		PLOG_ERROR << "TCP connect: " << e.what();
+		changeState(State::Failed);
+		return;
+	}
+
+	// Receive loop
+	try {
+		PLOG_INFO << "TCP connected";
+		changeState(State::Connected);
+
+		while (true) {
+			fd_set readfds, writefds;
+			int n = prepareSelect(readfds, writefds);
+
+			struct timeval tv;
+			tv.tv_sec = 10;
+			tv.tv_usec = 0;
+			int ret = ::select(n, &readfds, &writefds, NULL, &tv);
+			if (ret < 0) {
+				throw std::runtime_error("Failed to wait on socket");
+			} else if (ret == 0) {
+				PLOG_VERBOSE << "TCP is idle";
+				incoming(make_message(0));
+				continue;
+			}
+
+			if (FD_ISSET(mSock, &writefds))
+				trySendQueue();
+
+			if (FD_ISSET(mSock, &readfds)) {
+				char buffer[bufferSize];
+				int len = ::recv(mSock, buffer, bufferSize, 0);
+				if (len < 0) {
+					if (errno == EAGAIN || errno == EWOULDBLOCK) {
+						continue;
+					} else {
+						throw std::runtime_error("Connection lost");
+					}
+				}
+
+				if (len == 0)
+					break; // clean close
+
+				auto *b = reinterpret_cast<byte *>(buffer);
+				incoming(make_message(b, b + len));
+			}
+		}
+	} catch (const std::exception &e) {
+		PLOG_ERROR << "TCP recv: " << e.what();
+	}
+
+	PLOG_INFO << "TCP disconnected";
+	changeState(State::Disconnected);
+	recv(nullptr);
+}
+
+int TcpTransport::prepareSelect(fd_set &readfds, fd_set &writefds) {
+	FD_ZERO(&readfds);
+	FD_ZERO(&writefds);
+	FD_SET(mSock, &readfds);
+
+	if (!mSendQueue.empty())
+		FD_SET(mSock, &writefds);
+
+	int n = SOCKET_TO_INT(mSock) + 1;
+	int m = mInterrupter.prepare(readfds, writefds);
+	return std::max(n, m);
+}
+
+void TcpTransport::interruptSelect() { mInterrupter.interrupt(); }
+
+} // namespace rtc
+
+#endif

src/tcptransport.hpp

@@ -0,0 +1,90 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_TCP_TRANSPORT_H
+#define RTC_TCP_TRANSPORT_H
+
+#include "include.hpp"
+#include "queue.hpp"
+#include "transport.hpp"
+
+#if RTC_ENABLE_WEBSOCKET
+
+#include <mutex>
+#include <thread>
+
+// Use the socket defines from libjuice
+#include "../deps/libjuice/src/socket.h"
+
+namespace rtc {
+
+// Utility class to interrupt select()
+class SelectInterrupter {
+public:
+	SelectInterrupter();
+	~SelectInterrupter();
+
+	int prepare(fd_set &readfds, fd_set &writefds);
+	void interrupt();
+
+private:
+	std::mutex mMutex;
+#ifdef _WIN32
+	socket_t mDummySock = INVALID_SOCKET;
+#else // assume POSIX
+	int mPipeIn, mPipeOut;
+#endif
+};
+
+class TcpTransport : public Transport {
+public:
+	TcpTransport(const string &hostname, const string &service, state_callback callback);
+	~TcpTransport();
+
+	bool stop() override;
+	bool send(message_ptr message) override;
+
+	void incoming(message_ptr message) override;
+	bool outgoing(message_ptr message) override;
+
+private:
+	void connect(const string &hostname, const string &service);
+	void connect(const sockaddr *addr, socklen_t addrlen);
+	void close();
+
+	bool trySendQueue();
+	bool trySendMessage(message_ptr &message);
+
+	void runLoop();
+
+	int prepareSelect(fd_set &readfds, fd_set &writefds);
+	void interruptSelect();
+
+	string mHostname, mService;
+
+	socket_t mSock = INVALID_SOCKET;
+	std::thread mThread;
+	SelectInterrupter mInterrupter;
+	Queue<message_ptr> mSendQueue;
+};
+
+} // namespace rtc
+
+#endif
+
+#endif

src/tls.cpp

@@ -0,0 +1,132 @@
+/**
+ * Copyright (c) 2019-2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "tls.hpp"
+
+#if USE_GNUTLS
+
+namespace rtc::gnutls {
+
+bool check(int ret, const string &message) {
+	if (ret < 0) {
+		if (!gnutls_error_is_fatal(ret)) {
+			PLOG_INFO << gnutls_strerror(ret);
+			return false;
+		}
+		PLOG_ERROR << message << ": " << gnutls_strerror(ret);
+		throw std::runtime_error(message + ": " + gnutls_strerror(ret));
+	}
+	return true;
+}
+
+gnutls_certificate_credentials_t *new_credentials() {
+	auto creds = new gnutls_certificate_credentials_t;
+	gnutls::check(gnutls_certificate_allocate_credentials(creds));
+	return creds;
+}
+
+void free_credentials(gnutls_certificate_credentials_t *creds) {
+	gnutls_certificate_free_credentials(*creds);
+	delete creds;
+}
+
+gnutls_x509_crt_t *new_crt() {
+	auto crt = new gnutls_x509_crt_t;
+	gnutls::check(gnutls_x509_crt_init(crt));
+	return crt;
+}
+
+void free_crt(gnutls_x509_crt_t *crt) {
+	gnutls_x509_crt_deinit(*crt);
+	delete crt;
+}
+
+gnutls_x509_privkey_t *new_privkey() {
+	auto privkey = new gnutls_x509_privkey_t;
+	gnutls::check(gnutls_x509_privkey_init(privkey));
+	return privkey;
+}
+
+void free_privkey(gnutls_x509_privkey_t *privkey) {
+	gnutls_x509_privkey_deinit(*privkey);
+	delete privkey;
+}
+
+gnutls_datum_t make_datum(char *data, size_t size) {
+	gnutls_datum_t datum;
+	datum.data = reinterpret_cast<unsigned char *>(data);
+	datum.size = size;
+	return datum;
+}
+
+} // namespace rtc::gnutls
+
+#else // USE_GNUTLS==0
+
+namespace rtc::openssl {
+
+void init() {
+	static std::mutex mutex;
+	static bool done = false;
+
+	std::lock_guard lock(mutex);
+	if (!done) {
+		OPENSSL_init_ssl(0, NULL);
+		SSL_load_error_strings();
+		ERR_load_crypto_strings();
+		done = true;
+	}
+}
+
+string error_string(unsigned long err) {
+	const size_t bufferSize = 256;
+	char buffer[bufferSize];
+	ERR_error_string_n(err, buffer, bufferSize);
+	return string(buffer);
+}
+
+bool check(int success, const string &message) {
+	if (success)
+		return true;
+
+	string str = error_string(ERR_get_error());
+	PLOG_ERROR << message << ": " << str;
+	throw std::runtime_error(message + ": " + str);
+}
+
+bool check(SSL *ssl, int ret, const string &message) {
+	if (ret == BIO_EOF)
+		return true;
+
+	unsigned long err = SSL_get_error(ssl, ret);
+	if (err == SSL_ERROR_NONE || err == SSL_ERROR_WANT_READ || err == SSL_ERROR_WANT_WRITE) {
+		return true;
+	}
+	if (err == SSL_ERROR_ZERO_RETURN) {
+		PLOG_DEBUG << "DTLS connection cleanly closed";
+		return false;
+	}
+	string str = error_string(err);
+	PLOG_ERROR << str;
+	throw std::runtime_error(message + ": " + str);
+}
+
+} // namespace rtc::openssl
+
+#endif
+

src/tls.hpp

@@ -0,0 +1,75 @@
+/**
+ * Copyright (c) 2019-2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_TLS_H
+#define RTC_TLS_H
+
+#include "include.hpp"
+
+#if USE_GNUTLS
+
+#include <gnutls/gnutls.h>
+
+#include <gnutls/crypto.h>
+#include <gnutls/dtls.h>
+#include <gnutls/x509.h>
+
+namespace rtc::gnutls {
+
+bool check(int ret, const string &message = "GnuTLS error");
+
+gnutls_certificate_credentials_t *new_credentials();
+void free_credentials(gnutls_certificate_credentials_t *creds);
+
+gnutls_x509_crt_t *new_crt();
+void free_crt(gnutls_x509_crt_t *crt);
+
+gnutls_x509_privkey_t *new_privkey();
+void free_privkey(gnutls_x509_privkey_t *privkey);
+
+gnutls_datum_t make_datum(char *data, size_t size);
+
+} // namespace rtc::gnutls
+
+#else // USE_GNUTLS==0
+
+#include <openssl/ssl.h>
+
+#include <openssl/bio.h>
+#include <openssl/ec.h>
+#include <openssl/err.h>
+#include <openssl/pem.h>
+#include <openssl/x509.h>
+
+#ifndef BIO_EOF
+#define BIO_EOF -1
+#endif
+
+namespace rtc::openssl {
+
+void init();
+string error_string(unsigned long err);
+
+bool check(int success, const string &message = "OpenSSL error");
+bool check(SSL *ssl, int ret, const string &message = "OpenSSL error");
+
+} // namespace rtc::openssl
+
+#endif
+
+#endif

src/tlstransport.cpp

@@ -0,0 +1,429 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "tlstransport.hpp"
+#include "tcptransport.hpp"
+
+#if RTC_ENABLE_WEBSOCKET
+
+#include <chrono>
+#include <cstring>
+#include <exception>
+#include <iostream>
+
+using namespace std::chrono;
+
+using std::shared_ptr;
+using std::string;
+using std::unique_ptr;
+using std::weak_ptr;
+
+namespace rtc {
+
+#if USE_GNUTLS
+
+void TlsTransport::Init() {
+	// Nothing to do
+}
+
+void TlsTransport::Cleanup() {
+	// Nothing to do
+}
+
+TlsTransport::TlsTransport(shared_ptr<TcpTransport> lower, string host, state_callback callback)
+    : Transport(lower, std::move(callback)), mHost(std::move(host)) {
+
+	PLOG_DEBUG << "Initializing TLS transport (GnuTLS)";
+
+	gnutls::check(gnutls_certificate_allocate_credentials(&mCreds));
+	gnutls::check(gnutls_init(&mSession, GNUTLS_CLIENT));
+
+	try {
+		gnutls::check(gnutls_certificate_set_x509_system_trust(mCreds));
+		gnutls::check(gnutls_credentials_set(mSession, GNUTLS_CRD_CERTIFICATE, mCreds));
+		gnutls_session_set_verify_cert(mSession, mHost.c_str(), 0);
+
+		const char *priorities = "SECURE128:-VERS-SSL3.0:-ARCFOUR-128";
+		const char *err_pos = NULL;
+		gnutls::check(gnutls_priority_set_direct(mSession, priorities, &err_pos),
+		              "Failed to set TLS priorities");
+
+       	PLOG_VERBOSE << "Server Name Indication: " << mHost;
+		gnutls_server_name_set(mSession, GNUTLS_NAME_DNS, mHost.data(), mHost.size());
+
+ 		gnutls_session_set_ptr(mSession, this);
+		gnutls_transport_set_ptr(mSession, this);
+		gnutls_transport_set_push_function(mSession, WriteCallback);
+		gnutls_transport_set_pull_function(mSession, ReadCallback);
+		gnutls_transport_set_pull_timeout_function(mSession, TimeoutCallback);
+
+       	mRecvThread = std::thread(&TlsTransport::runRecvLoop, this);
+		registerIncoming();
+
+	} catch (...) {
+		gnutls_deinit(mSession);
+		gnutls_certificate_free_credentials(mCreds);
+		throw;
+	}
+}
+
+TlsTransport::~TlsTransport() {
+	stop();
+
+	gnutls_deinit(mSession);
+	gnutls_certificate_free_credentials(mCreds);
+}
+
+bool TlsTransport::stop() {
+	if (!Transport::stop())
+		return false;
+
+	PLOG_DEBUG << "Stopping TLS recv thread";
+	mIncomingQueue.stop();
+	mRecvThread.join();
+	return true;
+}
+
+bool TlsTransport::send(message_ptr message) {
+	if (!message || state() != State::Connected)
+		return false;
+
+	PLOG_VERBOSE << "Send size=" << message->size();
+
+	if(message->size() == 0)
+		return true;
+
+	ssize_t ret;
+	do {
+		ret = gnutls_record_send(mSession, message->data(), message->size());
+	} while (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN);
+
+	return gnutls::check(ret);
+}
+
+void TlsTransport::incoming(message_ptr message) {
+	if (message)
+		mIncomingQueue.push(message);
+	else
+		mIncomingQueue.stop();
+}
+
+void TlsTransport::runRecvLoop() {
+	const size_t bufferSize = 4096;
+	char buffer[bufferSize];
+
+	// Handshake loop
+	try {
+		changeState(State::Connecting);
+
+		int ret;
+		do {
+			ret = gnutls_handshake(mSession);
+		} while (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN ||
+		         !gnutls::check(ret, "TLS handshake failed"));
+
+	} catch (const std::exception &e) {
+		PLOG_ERROR << "TLS handshake: " << e.what();
+		changeState(State::Failed);
+		return;
+	}
+
+	// Receive loop
+	try {
+		PLOG_INFO << "TLS handshake finished";
+		changeState(State::Connected);
+
+		while (true) {
+			ssize_t ret;
+			do {
+				ret = gnutls_record_recv(mSession, buffer, bufferSize);
+			} while (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN);
+
+			// Consider premature termination as remote closing
+			if (ret == GNUTLS_E_PREMATURE_TERMINATION) {
+				PLOG_DEBUG << "TLS connection terminated";
+				break;
+			}
+
+			if (gnutls::check(ret)) {
+				if (ret == 0) {
+					// Closed
+					PLOG_DEBUG << "TLS connection cleanly closed";
+					break;
+				}
+				auto *b = reinterpret_cast<byte *>(buffer);
+				recv(make_message(b, b + ret));
+			}
+		}
+	} catch (const std::exception &e) {
+		PLOG_ERROR << "TLS recv: " << e.what();
+	}
+
+	gnutls_bye(mSession, GNUTLS_SHUT_RDWR);
+
+	PLOG_INFO << "TLS closed";
+	changeState(State::Disconnected);
+	recv(nullptr);
+}
+
+ssize_t TlsTransport::WriteCallback(gnutls_transport_ptr_t ptr, const void *data, size_t len) {
+	TlsTransport *t = static_cast<TlsTransport *>(ptr);
+	if (len > 0) {
+		auto b = reinterpret_cast<const byte *>(data);
+		t->outgoing(make_message(b, b + len));
+	}
+	gnutls_transport_set_errno(t->mSession, 0);
+	return ssize_t(len);
+}
+
+ssize_t TlsTransport::ReadCallback(gnutls_transport_ptr_t ptr, void *data, size_t maxlen) {
+	TlsTransport *t = static_cast<TlsTransport *>(ptr);
+
+	message_ptr &message = t->mIncomingMessage;
+	size_t &position = t->mIncomingMessagePosition;
+
+	if(message && position >= message->size())
+		message.reset();
+
+	if(!message) {
+		position = 0;
+		while (auto next = t->mIncomingQueue.pop()) {
+			message = *next;
+			if (message->size() > 0)
+				break;
+			else
+				t->recv(message); // Pass zero-sized messages through
+		}
+	}
+
+	if(message) {
+		size_t available = message->size() - position;
+		ssize_t len = std::min(maxlen, available);
+		std::memcpy(data, message->data() + position, len);
+		position+= len;
+		gnutls_transport_set_errno(t->mSession, 0);
+		return len;
+	}
+	else {
+		// Closed
+		gnutls_transport_set_errno(t->mSession, 0);
+		return 0;
+	}
+}
+
+int TlsTransport::TimeoutCallback(gnutls_transport_ptr_t ptr, unsigned int ms) {
+	TlsTransport *t = static_cast<TlsTransport *>(ptr);
+	if (ms != GNUTLS_INDEFINITE_TIMEOUT)
+		t->mIncomingQueue.wait(milliseconds(ms));
+	else
+		t->mIncomingQueue.wait();
+	return !t->mIncomingQueue.empty() ? 1 : 0;
+}
+
+#else // USE_GNUTLS==0
+
+int TlsTransport::TransportExIndex = -1;
+
+void TlsTransport::Init() {
+	openssl::init();
+
+	if (TransportExIndex < 0) {
+		TransportExIndex = SSL_get_ex_new_index(0, NULL, NULL, NULL, NULL);
+	}
+}
+
+void TlsTransport::Cleanup() {
+	// Nothing to do
+}
+
+TlsTransport::TlsTransport(shared_ptr<TcpTransport> lower, string host, state_callback callback)
+    : Transport(lower, std::move(callback)), mHost(std::move(host)) {
+
+	PLOG_DEBUG << "Initializing TLS transport (OpenSSL)";
+
+	try {
+		if (!(mCtx = SSL_CTX_new(SSLv23_method()))) // version-flexible
+			throw std::runtime_error("Failed to create SSL context");
+
+		openssl::check(SSL_CTX_set_cipher_list(mCtx, "ALL:!LOW:!EXP:!RC4:!MD5:@STRENGTH"),
+		               "Failed to set SSL priorities");
+
+		SSL_CTX_set_options(mCtx, SSL_OP_NO_SSLv3);
+		SSL_CTX_set_min_proto_version(mCtx, TLS1_VERSION);
+		SSL_CTX_set_read_ahead(mCtx, 1);
+		SSL_CTX_set_quiet_shutdown(mCtx, 1);
+		SSL_CTX_set_info_callback(mCtx, InfoCallback);
+
+		SSL_CTX_set_default_verify_paths(mCtx);
+		SSL_CTX_set_verify(mCtx, SSL_VERIFY_PEER, NULL);
+		SSL_CTX_set_verify_depth(mCtx, 4);
+
+		if (!(mSsl = SSL_new(mCtx)))
+			throw std::runtime_error("Failed to create SSL instance");
+
+		SSL_set_ex_data(mSsl, TransportExIndex, this);
+
+		SSL_set_hostflags(mSsl, 0);
+		openssl::check(SSL_set1_host(mSsl, mHost.c_str()), "Failed to set SSL host");
+
+		PLOG_VERBOSE << "Server Name Indication: " << mHost;
+		SSL_set_tlsext_host_name(mSsl, mHost.c_str());
+
+		SSL_set_connect_state(mSsl);
+
+		if (!(mInBio = BIO_new(BIO_s_mem())) || !(mOutBio = BIO_new(BIO_s_mem())))
+			throw std::runtime_error("Failed to create BIO");
+
+		BIO_set_mem_eof_return(mInBio, BIO_EOF);
+		BIO_set_mem_eof_return(mOutBio, BIO_EOF);
+		SSL_set_bio(mSsl, mInBio, mOutBio);
+
+		auto ecdh = unique_ptr<EC_KEY, decltype(&EC_KEY_free)>(
+		    EC_KEY_new_by_curve_name(NID_X9_62_prime256v1), EC_KEY_free);
+		SSL_set_options(mSsl, SSL_OP_SINGLE_ECDH_USE);
+		SSL_set_tmp_ecdh(mSsl, ecdh.get());
+
+		mRecvThread = std::thread(&TlsTransport::runRecvLoop, this);
+		registerIncoming();
+
+	} catch (...) {
+		if (mSsl)
+			SSL_free(mSsl);
+		if (mCtx)
+			SSL_CTX_free(mCtx);
+		throw;
+	}
+}
+
+TlsTransport::~TlsTransport() {
+	stop();
+
+	SSL_free(mSsl);
+	SSL_CTX_free(mCtx);
+}
+
+bool TlsTransport::stop() {
+	if (!Transport::stop())
+		return false;
+
+	PLOG_DEBUG << "Stopping TLS recv thread";
+	mIncomingQueue.stop();
+	mRecvThread.join();
+	SSL_shutdown(mSsl);
+	return true;
+}
+
+bool TlsTransport::send(message_ptr message) {
+	if (!message || state() != State::Connected)
+		return false;
+
+	PLOG_VERBOSE << "Send size=" << message->size();
+
+	if (message->size() == 0)
+		return true;
+
+	int ret = SSL_write(mSsl, message->data(), message->size());
+	if (!openssl::check(mSsl, ret))
+		return false;
+
+	const size_t bufferSize = 4096;
+	byte buffer[bufferSize];
+	while ((ret = BIO_read(mOutBio, buffer, bufferSize)) > 0)
+		outgoing(make_message(buffer, buffer + ret));
+
+	return true;
+}
+
+void TlsTransport::incoming(message_ptr message) {
+	if (message)
+		mIncomingQueue.push(message);
+	else
+		mIncomingQueue.stop();
+}
+
+void TlsTransport::runRecvLoop() {
+	const size_t bufferSize = 4096;
+	byte buffer[bufferSize];
+
+	try {
+		changeState(State::Connecting);
+
+		while (true) {
+			if (state() == State::Connecting) {
+				// Initiate or continue the handshake
+				int ret = SSL_do_handshake(mSsl);
+				if (!openssl::check(mSsl, ret, "Handshake failed"))
+					break;
+
+				// Output
+				while ((ret = BIO_read(mOutBio, buffer, bufferSize)) > 0)
+					outgoing(make_message(buffer, buffer + ret));
+
+				if (SSL_is_init_finished(mSsl)) {
+					PLOG_INFO << "TLS handshake finished";
+					changeState(State::Connected);
+				}
+			} else {
+				int ret = SSL_read(mSsl, buffer, bufferSize);
+				if (!openssl::check(mSsl, ret))
+					break;
+
+				if (ret > 0)
+					recv(make_message(buffer, buffer + ret));
+			}
+
+			auto next = mIncomingQueue.pop();
+			if (!next)
+				break;
+
+			message_ptr message = *next;
+			if (message->size() > 0)
+				BIO_write(mInBio, message->data(), message->size()); // Input
+			else
+				recv(message); // Pass zero-sized messages through
+		}
+
+	} catch (const std::exception &e) {
+		PLOG_ERROR << "TLS recv: " << e.what();
+	}
+
+	if (state() == State::Connected) {
+		PLOG_INFO << "TLS closed";
+		recv(nullptr);
+	} else {
+		PLOG_ERROR << "TLS handshake failed";
+	}
+}
+
+void TlsTransport::InfoCallback(const SSL *ssl, int where, int ret) {
+	TlsTransport *t =
+	    static_cast<TlsTransport *>(SSL_get_ex_data(ssl, TlsTransport::TransportExIndex));
+
+	if (where & SSL_CB_ALERT) {
+		if (ret != 256) { // Close Notify
+			PLOG_ERROR << "TLS alert: " << SSL_alert_desc_string_long(ret);
+		}
+		t->mIncomingQueue.stop(); // Close the connection
+	}
+}
+
+#endif
+
+} // namespace rtc
+
+#endif

src/tlstransport.hpp

@@ -0,0 +1,82 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_TLS_TRANSPORT_H
+#define RTC_TLS_TRANSPORT_H
+
+#include "include.hpp"
+#include "queue.hpp"
+#include "tls.hpp"
+#include "transport.hpp"
+
+#if RTC_ENABLE_WEBSOCKET
+
+#include <thread>
+
+namespace rtc {
+
+class TcpTransport;
+
+class TlsTransport : public Transport {
+public:
+	static void Init();
+	static void Cleanup();
+
+	TlsTransport(std::shared_ptr<TcpTransport> lower, string host, state_callback callback);
+	~TlsTransport();
+
+	bool stop() override;
+	bool send(message_ptr message) override;
+
+	void incoming(message_ptr message) override;
+
+protected:
+	void runRecvLoop();
+
+	string mHost;
+
+	Queue<message_ptr> mIncomingQueue;
+	std::thread mRecvThread;
+
+#if USE_GNUTLS
+	gnutls_session_t mSession;
+	gnutls_certificate_credentials_t mCreds;
+
+	message_ptr mIncomingMessage;
+	size_t mIncomingMessagePosition = 0;
+
+	static ssize_t WriteCallback(gnutls_transport_ptr_t ptr, const void *data, size_t len);
+	static ssize_t ReadCallback(gnutls_transport_ptr_t ptr, void *data, size_t maxlen);
+	static int TimeoutCallback(gnutls_transport_ptr_t ptr, unsigned int ms);
+#else
+	SSL_CTX *mCtx;
+	SSL *mSsl;
+	BIO *mInBio, *mOutBio;
+
+	static int TransportExIndex;
+
+	static int CertificateCallback(int preverify_ok, X509_STORE_CTX *ctx);
+	static void InfoCallback(const SSL *ssl, int where, int ret);
+#endif
+};
+
+} // namespace rtc
+
+#endif
+
+#endif

src/transport.hpp

@@ -22,6 +22,7 @@
 #include "include.hpp"
 #include "message.hpp"
 
+#include <atomic>
 #include <functional>
 #include <memory>
 
@@ -31,36 +32,55 @@ using namespace std::placeholders;
 
 class Transport {
 public:
-	Transport(std::shared_ptr<Transport> lower = nullptr) : mLower(lower) { init(); }
+	enum class State { Disconnected, Connecting, Connected, Completed, Failed };
-	virtual ~Transport() {}
+	using state_callback = std::function<void(State state)>;
 
-	virtual bool send(message_ptr message) = 0;
+	Transport(std::shared_ptr<Transport> lower = nullptr, state_callback callback = nullptr)
-	void onRecv(message_callback callback) { mRecvCallback = std::move(callback); }
+	    : mLower(std::move(lower)), mStateChangeCallback(std::move(callback)) {
-
-protected:
-	void recv(message_ptr message) {
-		if (mRecvCallback)
-			mRecvCallback(message);
 	}
 
-	virtual void incoming(message_ptr message) = 0;
+	virtual ~Transport() {
-	virtual void outgoing(message_ptr message) { getLower()->send(message); }
+		stop();
+		if (mLower)
+			mLower->onRecv(nullptr); // doing it on stop could cause a deadlock
+	}
 
-private:
+	virtual bool stop() {
-	void init() {
+		return !mShutdown.exchange(true);
+	}
+
+	void registerIncoming() {
 		if (mLower)
 			mLower->onRecv(std::bind(&Transport::incoming, this, _1));
 	}
 
-	std::shared_ptr<Transport> getLower() {
+	void onRecv(message_callback callback) { mRecvCallback = std::move(callback); }
-		if (mLower)
+	State state() const { return mState; }
-			return mLower;
+
-		else
+	virtual bool send(message_ptr message) { return outgoing(message); }
-			throw std::logic_error("No lower transport to call");
+
+protected:
+	void recv(message_ptr message) { mRecvCallback(message); }
+	void changeState(State state) {
+		if (mState.exchange(state) != state)
+			mStateChangeCallback(state);
 	}
 
+	virtual void incoming(message_ptr message) { recv(message); }
+	virtual bool outgoing(message_ptr message) {
+		if (mLower)
+			return mLower->send(message);
+		else
+			return false;
+	}
+
+private:
 	std::shared_ptr<Transport> mLower;
-	message_callback mRecvCallback;
+	synchronized_callback<State> mStateChangeCallback;
+	synchronized_callback<message_ptr> mRecvCallback;
+
+	std::atomic<State> mState = State::Disconnected;
+	std::atomic<bool> mShutdown = false;
 };
 
 } // namespace rtc

src/websocket.cpp

@@ -0,0 +1,323 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#if RTC_ENABLE_WEBSOCKET
+
+#include "include.hpp"
+#include "websocket.hpp"
+
+#include "tcptransport.hpp"
+#include "tlstransport.hpp"
+#include "wstransport.hpp"
+
+#include <regex>
+
+#ifdef _WIN32
+#include <winsock2.h>
+#endif
+
+namespace rtc {
+
+WebSocket::WebSocket() { PLOG_VERBOSE << "Creating WebSocket"; }
+
+WebSocket::~WebSocket() {
+	PLOG_VERBOSE << "Destroying WebSocket";
+	remoteClose();
+}
+
+WebSocket::State WebSocket::readyState() const { return mState; }
+
+void WebSocket::open(const string &url) {
+	if (mState != State::Closed)
+		throw std::runtime_error("WebSocket must be closed before opening");
+
+	static const char *rs = R"(^(([^:\/?#]+):)?(//([^\/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?)";
+	static std::regex regex(rs, std::regex::extended);
+
+	std::smatch match;
+	if (!std::regex_match(url, match, regex))
+		throw std::invalid_argument("Malformed WebSocket URL: " + url);
+
+	mScheme = match[2];
+	if (mScheme != "ws" && mScheme != "wss")
+		throw std::invalid_argument("Invalid WebSocket scheme: " + mScheme);
+
+	mHost = match[4];
+	if (auto pos = mHost.find(':'); pos != string::npos) {
+		mHostname = mHost.substr(0, pos);
+		mService = mHost.substr(pos + 1);
+	} else {
+		mHostname = mHost;
+		mService = mScheme == "ws" ? "80" : "443";
+	}
+
+	mPath = match[5];
+	if (string query = match[7]; !query.empty())
+		mPath += "?" + query;
+
+	changeState(State::Connecting);
+	initTcpTransport();
+}
+
+void WebSocket::close() {
+	auto state = mState.load();
+	if (state == State::Connecting || state == State::Open) {
+		PLOG_VERBOSE << "Closing WebSocket";
+		changeState(State::Closing);
+		if (auto transport = std::atomic_load(&mWsTransport))
+			transport->close();
+		else
+			changeState(State::Closed);
+	}
+}
+
+void WebSocket::remoteClose() {
+	if (mState.load() != State::Closed) {
+		close();
+		closeTransports();
+	}
+}
+
+bool WebSocket::send(const std::variant<binary, string> &data) {
+	return std::visit(
+	    [&](const auto &d) {
+		    using T = std::decay_t<decltype(d)>;
+		    constexpr auto type = std::is_same_v<T, string> ? Message::String : Message::Binary;
+		    auto *b = reinterpret_cast<const byte *>(d.data());
+		    return outgoing(std::make_shared<Message>(b, b + d.size(), type));
+	    },
+	    data);
+}
+
+bool WebSocket::isOpen() const { return mState == State::Open; }
+
+bool WebSocket::isClosed() const { return mState == State::Closed; }
+
+size_t WebSocket::maxMessageSize() const { return DEFAULT_MAX_MESSAGE_SIZE; }
+
+std::optional<std::variant<binary, string>> WebSocket::receive() {
+	while (!mRecvQueue.empty()) {
+		auto message = *mRecvQueue.pop();
+		switch (message->type) {
+		case Message::String:
+			return std::make_optional(
+			    string(reinterpret_cast<const char *>(message->data()), message->size()));
+		case Message::Binary:
+			return std::make_optional(std::move(*message));
+		default:
+			// Ignore
+			break;
+		}
+	}
+	return nullopt;
+}
+
+size_t WebSocket::availableAmount() const { return mRecvQueue.amount(); }
+
+bool WebSocket::changeState(State state) { return mState.exchange(state) != state; }
+
+bool WebSocket::outgoing(message_ptr message) {
+	if (mState != State::Open || !mWsTransport)
+		throw std::runtime_error("WebSocket is not open");
+
+	if (message->size() > maxMessageSize())
+		throw std::runtime_error("Message size exceeds limit");
+
+	return mWsTransport->send(message);
+}
+
+void WebSocket::incoming(message_ptr message) {
+	if (message->type == Message::String || message->type == Message::Binary) {
+		mRecvQueue.push(message);
+		triggerAvailable(mRecvQueue.size());
+	}
+}
+
+std::shared_ptr<TcpTransport> WebSocket::initTcpTransport() {
+	using State = TcpTransport::State;
+	try {
+		std::lock_guard lock(mInitMutex);
+		if (auto transport = std::atomic_load(&mTcpTransport))
+			return transport;
+
+		auto transport = std::make_shared<TcpTransport>(
+		    mHostname, mService, [this, weak_this = weak_from_this()](State state) {
+			    auto shared_this = weak_this.lock();
+			    if (!shared_this)
+				    return;
+			    switch (state) {
+			    case State::Connected:
+				    if (mScheme == "ws")
+					    initWsTransport();
+				    else
+					    initTlsTransport();
+				    break;
+			    case State::Failed:
+				    triggerError("TCP connection failed");
+				    remoteClose();
+				    break;
+			    case State::Disconnected:
+				    remoteClose();
+				    break;
+			    default:
+				    // Ignore
+				    break;
+			    }
+		    });
+		std::atomic_store(&mTcpTransport, transport);
+		if (mState == WebSocket::State::Closed) {
+			mTcpTransport.reset();
+			transport->stop();
+			throw std::runtime_error("Connection is closed");
+		}
+		return transport;
+	} catch (const std::exception &e) {
+		PLOG_ERROR << e.what();
+		remoteClose();
+		throw std::runtime_error("TCP transport initialization failed");
+	}
+}
+
+std::shared_ptr<TlsTransport> WebSocket::initTlsTransport() {
+	using State = TlsTransport::State;
+	try {
+		std::lock_guard lock(mInitMutex);
+		if (auto transport = std::atomic_load(&mTlsTransport))
+			return transport;
+
+		auto lower = std::atomic_load(&mTcpTransport);
+		auto transport = std::make_shared<TlsTransport>(
+		    lower, mHost, [this, weak_this = weak_from_this()](State state) {
+			    auto shared_this = weak_this.lock();
+			    if (!shared_this)
+				    return;
+			    switch (state) {
+			    case State::Connected:
+				    initWsTransport();
+				    break;
+			    case State::Failed:
+				    triggerError("TCP connection failed");
+				    remoteClose();
+				    break;
+			    case State::Disconnected:
+				    remoteClose();
+				    break;
+			    default:
+				    // Ignore
+				    break;
+			    }
+		    });
+		std::atomic_store(&mTlsTransport, transport);
+		if (mState == WebSocket::State::Closed) {
+			mTlsTransport.reset();
+			transport->stop();
+			throw std::runtime_error("Connection is closed");
+		}
+		return transport;
+	} catch (const std::exception &e) {
+		PLOG_ERROR << e.what();
+		remoteClose();
+		throw std::runtime_error("TLS transport initialization failed");
+	}
+}
+
+std::shared_ptr<WsTransport> WebSocket::initWsTransport() {
+	using State = WsTransport::State;
+	try {
+		std::lock_guard lock(mInitMutex);
+		if (auto transport = std::atomic_load(&mWsTransport))
+			return transport;
+
+		std::shared_ptr<Transport> lower = std::atomic_load(&mTlsTransport);
+		if (!lower)
+			lower = std::atomic_load(&mTcpTransport);
+		auto transport = std::make_shared<WsTransport>(
+		    lower, mHost, mPath, weak_bind(&WebSocket::incoming, this, _1),
+		    [this, weak_this = weak_from_this()](State state) {
+			    auto shared_this = weak_this.lock();
+			    if (!shared_this)
+				    return;
+			    switch (state) {
+			    case State::Connected:
+				    if (mState == WebSocket::State::Connecting) {
+					    PLOG_DEBUG << "WebSocket open";
+					    changeState(WebSocket::State::Open);
+					    triggerOpen();
+				    }
+				    break;
+			    case State::Failed:
+				    triggerError("WebSocket connection failed");
+				    remoteClose();
+				    break;
+			    case State::Disconnected:
+				    remoteClose();
+				    break;
+			    default:
+				    // Ignore
+				    break;
+			    }
+		    });
+		std::atomic_store(&mWsTransport, transport);
+		if (mState == WebSocket::State::Closed) {
+			mWsTransport.reset();
+			transport->stop();
+			throw std::runtime_error("Connection is closed");
+		}
+		return transport;
+	} catch (const std::exception &e) {
+		PLOG_ERROR << e.what();
+		remoteClose();
+		throw std::runtime_error("WebSocket transport initialization failed");
+	}
+}
+
+void WebSocket::closeTransports() {
+	PLOG_VERBOSE << "Closing transports";
+
+	if (mState.load() != State::Closed) {
+		changeState(State::Closed);
+		triggerClosed();
+	}
+
+	// Reset callbacks now that state is changed
+	resetCallbacks();
+
+	// Pass the references to a thread, allowing to terminate a transport from its own thread
+	auto ws = std::atomic_exchange(&mWsTransport, decltype(mWsTransport)(nullptr));
+	auto tls = std::atomic_exchange(&mTlsTransport, decltype(mTlsTransport)(nullptr));
+	auto tcp = std::atomic_exchange(&mTcpTransport, decltype(mTcpTransport)(nullptr));
+	if (ws || tls || tcp) {
+		std::thread t([ws, tls, tcp, token = mInitToken]() mutable {
+			if (ws)
+				ws->stop();
+			if (tls)
+				tls->stop();
+			if (tcp)
+				tcp->stop();
+
+			ws.reset();
+			tls.reset();
+			tcp.reset();
+		});
+		t.detach();
+	}
+}
+
+} // namespace rtc
+
+#endif

src/wstransport.cpp

@@ -0,0 +1,400 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "wstransport.hpp"
+#include "tcptransport.hpp"
+#include "tlstransport.hpp"
+#include "base64.hpp"
+
+#if RTC_ENABLE_WEBSOCKET
+
+#include <chrono>
+#include <list>
+#include <map>
+#include <random>
+#include <regex>
+
+#ifdef _WIN32
+#include <winsock2.h>
+#else
+#include <arpa/inet.h>
+#endif
+
+#ifndef htonll
+#define htonll(x)                                                                                  \
+	((uint64_t)htonl(((uint64_t)(x)&0xFFFFFFFF) << 32) | (uint64_t)htonl((uint64_t)(x) >> 32))
+#endif
+#ifndef ntohll
+#define ntohll(x) htonll(x)
+#endif
+
+namespace rtc {
+
+using namespace std::chrono;
+using std::to_integer;
+using std::to_string;
+
+using random_bytes_engine =
+    std::independent_bits_engine<std::default_random_engine, CHAR_BIT, unsigned char>;
+
+WsTransport::WsTransport(std::shared_ptr<Transport> lower, string host, string path,
+                         message_callback recvCallback, state_callback stateCallback)
+    : Transport(lower, std::move(stateCallback)), mHost(std::move(host)), mPath(std::move(path)) {
+	onRecv(recvCallback);
+
+	PLOG_DEBUG << "Initializing WebSocket transport";
+
+	registerIncoming();
+	sendHttpRequest();
+}
+
+WsTransport::~WsTransport() { stop(); }
+
+bool WsTransport::stop() {
+	if (!Transport::stop())
+		return false;
+
+	close();
+	return true;
+}
+
+bool WsTransport::send(message_ptr message) {
+	if (!message || state() != State::Connected)
+		return false;
+
+	PLOG_VERBOSE << "Send size=" << message->size();
+	return sendFrame({message->type == Message::String ? TEXT_FRAME : BINARY_FRAME, message->data(),
+	                  message->size(), true, true});
+}
+
+void WsTransport::incoming(message_ptr message) {
+	auto s = state();
+	if (s != State::Connecting && s != State::Connected)
+		return; // Drop
+
+	if (message) {
+		PLOG_VERBOSE << "Incoming size=" << message->size();
+
+		if (message->size() == 0) {
+			// TCP is idle, send a ping
+			PLOG_DEBUG << "WebSocket sending ping";
+			uint32_t dummy = 0;
+			sendFrame({PING, reinterpret_cast<byte *>(&dummy), 4, true, true});
+			return;
+		}
+
+		mBuffer.insert(mBuffer.end(), message->begin(), message->end());
+
+		try {
+			if (state() == State::Connecting) {
+				if (size_t len = readHttpResponse(mBuffer.data(), mBuffer.size())) {
+					PLOG_INFO << "WebSocket open";
+					changeState(State::Connected);
+					mBuffer.erase(mBuffer.begin(), mBuffer.begin() + len);
+				}
+			}
+
+			if (state() == State::Connected) {
+				Frame frame;
+				while (size_t len = readFrame(mBuffer.data(), mBuffer.size(), frame)) {
+					recvFrame(frame);
+					mBuffer.erase(mBuffer.begin(), mBuffer.begin() + len);
+				}
+			}
+
+			return;
+
+		} catch (const std::exception &e) {
+			PLOG_ERROR << e.what();
+		}
+	}
+
+	if (state() == State::Connected) {
+		PLOG_INFO << "WebSocket disconnected";
+		changeState(State::Disconnected);
+		recv(nullptr);
+	} else {
+		PLOG_ERROR << "WebSocket handshake failed";
+		changeState(State::Failed);
+	}
+}
+
+void WsTransport::close() {
+	if (state() == State::Connected) {
+		sendFrame({CLOSE, NULL, 0, true, true});
+		PLOG_INFO << "WebSocket closing";
+		changeState(State::Disconnected);
+	}
+}
+
+bool WsTransport::sendHttpRequest() {
+	changeState(State::Connecting);
+
+	auto seed = system_clock::now().time_since_epoch().count();
+	random_bytes_engine generator(seed);
+
+	binary key(16);
+	auto k = reinterpret_cast<uint8_t *>(key.data());
+	std::generate(k, k + key.size(), generator);
+
+	const string request = "GET " + mPath +
+	                       " HTTP/1.1\r\n"
+	                       "Host: " +
+	                       mHost +
+	                       "\r\n"
+	                       "Connection: Upgrade\r\n"
+	                       "Upgrade: websocket\r\n"
+	                       "Sec-WebSocket-Version: 13\r\n"
+	                       "Sec-WebSocket-Key: " +
+	                       to_base64(key) +
+	                       "\r\n"
+	                       "\r\n";
+
+	auto data = reinterpret_cast<const byte *>(request.data());
+	auto size = request.size();
+	return outgoing(make_message(data, data + size));
+}
+
+size_t WsTransport::readHttpResponse(const byte *buffer, size_t size) {
+	std::list<string> lines;
+	auto begin = reinterpret_cast<const char *>(buffer);
+	auto end = begin + size;
+	auto cur = begin;
+
+	while (true) {
+		auto last = cur;
+		cur = std::find(cur, end, '\n');
+		if (cur == end)
+			return 0;
+		string line(last, cur != begin && *std::prev(cur) == '\r' ? std::prev(cur++) : cur++);
+		if (line.empty())
+			break;
+		lines.emplace_back(std::move(line));
+	}
+	size_t length = cur - begin;
+
+	if (lines.empty())
+		throw std::runtime_error("Invalid HTTP response for WebSocket");
+
+	string status = std::move(lines.front());
+	lines.pop_front();
+
+	std::istringstream ss(status);
+	string protocol;
+	unsigned int code = 0;
+	ss >> protocol >> code;
+	PLOG_DEBUG << "WebSocket response code: " << code;
+	if (code != 101)
+		throw std::runtime_error("Unexpected response code for WebSocket: " + to_string(code));
+
+	std::multimap<string, string> headers;
+	for (const auto &line : lines) {
+		if (size_t pos = line.find_first_of(':'); pos != string::npos) {
+			string key = line.substr(0, pos);
+			string value = line.substr(line.find_first_not_of(' ', pos + 1));
+			std::transform(key.begin(), key.end(), key.begin(),
+			               [](char c) { return std::tolower(c); });
+			headers.emplace(std::move(key), std::move(value));
+		} else {
+			headers.emplace(line, "");
+		}
+	}
+
+	auto h = headers.find("upgrade");
+	if (h == headers.end() || h->second != "websocket")
+		throw std::runtime_error("WebSocket update header missing or mismatching");
+
+	h = headers.find("sec-websocket-accept");
+	if (h == headers.end())
+		throw std::runtime_error("WebSocket accept header missing");
+
+	// TODO: Verify Sec-WebSocket-Accept
+
+	return length;
+}
+
+// http://tools.ietf.org/html/rfc6455#section-5.2  Base Framing Protocol
+//
+//  0                   1                   2                   3
+//  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+// +-+-+-+-+-------+-+-------------+-------------------------------+
+// |F|R|R|R| opcode|M| Payload len |    Extended payload length    |
+// |I|S|S|S|  (4)  |A|     (7)     |             (16/64)           |
+// |N|V|V|V|       |S|             |   (if payload len==126/127)   |
+// | |1|2|3|       |K|             |                               |
+// +-+-+-+-+-------+-+-------------+ - - - - - - - - - - - - - - - +
+// |    Extended payload length continued, if payload len == 127   |
+// + - - - - - - - - - - - - - - - +-------------------------------+
+// |                               | Masking-key, if MASK set to 1 |
+// +-------------------------------+-------------------------------+
+// |    Masking-key (continued)    |          Payload Data         |
+// +-------------------------------+ - - - - - - - - - - - - - - - +
+// :                     Payload Data continued ...                :
+// + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +
+// |                     Payload Data continued ...                |
+// +---------------------------------------------------------------+
+
+size_t WsTransport::readFrame(byte *buffer, size_t size, Frame &frame) {
+	const byte *end = buffer + size;
+	if (end - buffer < 2)
+		return 0;
+
+	byte *cur = buffer;
+	auto b1 = to_integer<uint8_t>(*cur++);
+	auto b2 = to_integer<uint8_t>(*cur++);
+
+	frame.fin = (b1 & 0x80) != 0;
+	frame.mask = (b2 & 0x80) != 0;
+	frame.opcode = static_cast<Opcode>(b1 & 0x0F);
+	frame.length = b2 & 0x7F;
+
+	if (frame.length == 0x7E) {
+		if (end - cur < 2)
+			return 0;
+		frame.length = ntohs(*reinterpret_cast<const uint16_t *>(cur));
+		cur += 2;
+	} else if (frame.length == 0x7F) {
+		if (end - cur < 8)
+			return 0;
+		frame.length = ntohll(*reinterpret_cast<const uint64_t *>(cur));
+		cur += 8;
+	}
+
+	const byte *maskingKey = nullptr;
+	if (frame.mask) {
+		if (end - cur < 4)
+			return 0;
+		maskingKey = cur;
+		cur += 4;
+	}
+
+	if (end - cur < frame.length)
+		return 0;
+
+	frame.payload = cur;
+	if (maskingKey)
+		for (size_t i = 0; i < frame.length; ++i)
+			frame.payload[i] ^= maskingKey[i % 4];
+	cur += frame.length;
+
+	return cur - buffer;
+}
+
+void WsTransport::recvFrame(const Frame &frame) {
+	PLOG_DEBUG << "WebSocket received frame: opcode=" << int(frame.opcode)
+	           << ", length=" << frame.length;
+
+	switch (frame.opcode) {
+	case TEXT_FRAME:
+	case BINARY_FRAME: {
+		if (!mPartial.empty()) {
+			PLOG_WARNING << "WebSocket unfinished message: type="
+			             << (mPartialOpcode == TEXT_FRAME ? "text" : "binary")
+			             << ", length=" << mPartial.size();
+			auto type = mPartialOpcode == TEXT_FRAME ? Message::String : Message::Binary;
+			recv(make_message(mPartial.begin(), mPartial.end(), type));
+			mPartial.clear();
+		}
+		mPartialOpcode = frame.opcode;
+		if (frame.fin) {
+			PLOG_DEBUG << "WebSocket finished message: type="
+			           << (frame.opcode == TEXT_FRAME ? "text" : "binary")
+			           << ", length=" << frame.length;
+			auto type = frame.opcode == TEXT_FRAME ? Message::String : Message::Binary;
+			recv(make_message(frame.payload, frame.payload + frame.length, type));
+		} else {
+			mPartial.insert(mPartial.end(), frame.payload, frame.payload + frame.length);
+		}
+		break;
+	}
+	case CONTINUATION: {
+		mPartial.insert(mPartial.end(), frame.payload, frame.payload + frame.length);
+		if (frame.fin) {
+			PLOG_DEBUG << "WebSocket finished message: type="
+			           << (frame.opcode == TEXT_FRAME ? "text" : "binary")
+			           << ", length=" << mPartial.size();
+			auto type = mPartialOpcode == TEXT_FRAME ? Message::String : Message::Binary;
+			recv(make_message(mPartial.begin(), mPartial.end(), type));
+			mPartial.clear();
+		}
+		break;
+	}
+	case PING: {
+		PLOG_DEBUG << "WebSocket received ping, sending pong";
+		sendFrame({PONG, frame.payload, frame.length, true, true});
+		break;
+	}
+	case PONG: {
+		PLOG_DEBUG << "WebSocket received pong";
+		break;
+	}
+	case CLOSE: {
+		close();
+		PLOG_INFO << "WebSocket closed";
+		changeState(State::Disconnected);
+		break;
+	}
+	default: {
+		close();
+		throw std::invalid_argument("Unknown WebSocket opcode: " + to_string(frame.opcode));
+	}
+	}
+}
+
+bool WsTransport::sendFrame(const Frame &frame) {
+	PLOG_DEBUG << "WebSocket sending frame: opcode=" << int(frame.opcode)
+	           << ", length=" << frame.length;
+
+	byte buffer[14];
+	byte *cur = buffer;
+
+	*cur++ = byte((frame.opcode & 0x0F) | (frame.fin ? 0x80 : 0));
+
+	if (frame.length < 0x7E) {
+		*cur++ = byte((frame.length & 0x7F) | (frame.mask ? 0x80 : 0));
+	} else if (frame.length <= 0xFFFF) {
+		*cur++ = byte(0x7E | (frame.mask ? 0x80 : 0));
+		*reinterpret_cast<uint16_t *>(cur) = htons(uint16_t(frame.length));
+		cur += 2;
+	} else {
+		*cur++ = byte(0x7F | (frame.mask ? 0x80 : 0));
+		*reinterpret_cast<uint64_t *>(cur) = htonll(uint64_t(frame.length));
+		cur += 8;
+	}
+
+	if (frame.mask) {
+		auto seed = system_clock::now().time_since_epoch().count();
+		random_bytes_engine generator(seed);
+
+		byte *maskingKey = reinterpret_cast<byte *>(cur);
+
+		auto u = reinterpret_cast<uint8_t *>(maskingKey);
+		std::generate(u, u + 4, generator);
+		cur += 4;
+
+		for (size_t i = 0; i < frame.length; ++i)
+			frame.payload[i] ^= maskingKey[i % 4];
+	}
+
+	outgoing(make_message(buffer, cur));                                        // header
+	return outgoing(make_message(frame.payload, frame.payload + frame.length)); // payload
+}
+
+} // namespace rtc
+
+#endif

src/wstransport.hpp

@@ -0,0 +1,82 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef RTC_WS_TRANSPORT_H
+#define RTC_WS_TRANSPORT_H
+
+#include "include.hpp"
+#include "transport.hpp"
+
+#if RTC_ENABLE_WEBSOCKET
+
+namespace rtc {
+
+class TcpTransport;
+class TlsTransport;
+
+class WsTransport : public Transport {
+public:
+	WsTransport(std::shared_ptr<Transport> lower, string host, string path,
+	            message_callback recvCallback, state_callback stateCallback);
+	~WsTransport();
+
+	bool stop() override;
+	bool send(message_ptr message) override;
+
+	void incoming(message_ptr message) override;
+
+	void close();
+
+private:
+	enum Opcode : uint8_t {
+		CONTINUATION = 0,
+		TEXT_FRAME = 1,
+		BINARY_FRAME = 2,
+		CLOSE = 8,
+		PING = 9,
+		PONG = 10,
+	};
+
+	struct Frame {
+		Opcode opcode = BINARY_FRAME;
+		byte *payload = nullptr;
+		size_t length = 0;
+		bool fin = true;
+		bool mask = true;
+	};
+
+	bool sendHttpRequest();
+	size_t readHttpResponse(const byte *buffer, size_t size);
+
+	size_t readFrame(byte *buffer, size_t size, Frame &frame);
+	void recvFrame(const Frame &frame);
+	bool sendFrame(const Frame &frame);
+
+	const string mHost;
+	const string mPath;
+
+	binary mBuffer;
+	binary mPartial;
+	Opcode mPartialOpcode;
+};
+
+} // namespace rtc
+
+#endif
+
+#endif

test/benchmark.cpp

@@ -0,0 +1,199 @@
+/**
+ * Copyright (c) 2019 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "rtc/rtc.hpp"
+
+#include <atomic>
+#include <chrono>
+#include <iostream>
+#include <memory>
+#include <thread>
+
+using namespace rtc;
+using namespace std;
+using namespace chrono_literals;
+
+using chrono::duration_cast;
+using chrono::milliseconds;
+using chrono::steady_clock;
+
+template <class T> weak_ptr<T> make_weak_ptr(shared_ptr<T> ptr) { return ptr; }
+
+size_t benchmark(milliseconds duration) {
+	rtc::InitLogger(LogLevel::Warning);
+	rtc::Preload();
+
+	Configuration config1;
+	// config1.iceServers.emplace_back("stun:stun.l.google.com:19302");
+
+	auto pc1 = std::make_shared<PeerConnection>(config1);
+
+	Configuration config2;
+	// config2.iceServers.emplace_back("stun:stun.l.google.com:19302");
+
+	auto pc2 = std::make_shared<PeerConnection>(config2);
+
+	pc1->onLocalDescription([wpc2 = make_weak_ptr(pc2)](const Description &sdp) {
+		auto pc2 = wpc2.lock();
+		if (!pc2)
+			return;
+		cout << "Description 1: " << sdp << endl;
+		pc2->setRemoteDescription(sdp);
+	});
+
+	pc1->onLocalCandidate([wpc2 = make_weak_ptr(pc2)](const Candidate &candidate) {
+		auto pc2 = wpc2.lock();
+		if (!pc2)
+			return;
+		cout << "Candidate 1: " << candidate << endl;
+		pc2->addRemoteCandidate(candidate);
+	});
+
+	pc1->onStateChange([](PeerConnection::State state) { cout << "State 1: " << state << endl; });
+	pc1->onGatheringStateChange([](PeerConnection::GatheringState state) {
+		cout << "Gathering state 1: " << state << endl;
+	});
+
+	pc2->onLocalDescription([wpc1 = make_weak_ptr(pc1)](const Description &sdp) {
+		auto pc1 = wpc1.lock();
+		if (!pc1)
+			return;
+		cout << "Description 2: " << sdp << endl;
+		pc1->setRemoteDescription(sdp);
+	});
+
+	pc2->onLocalCandidate([wpc1 = make_weak_ptr(pc1)](const Candidate &candidate) {
+		auto pc1 = wpc1.lock();
+		if (!pc1)
+			return;
+		cout << "Candidate 2: " << candidate << endl;
+		pc1->addRemoteCandidate(candidate);
+	});
+
+	pc2->onStateChange([](PeerConnection::State state) { cout << "State 2: " << state << endl; });
+	pc2->onGatheringStateChange([](PeerConnection::GatheringState state) {
+		cout << "Gathering state 2: " << state << endl;
+	});
+
+	const size_t messageSize = 65535;
+	binary messageData(messageSize);
+	fill(messageData.begin(), messageData.end(), byte(0xFF));
+
+	atomic<size_t> receivedSize = 0;
+	atomic<bool> finished = false;
+
+	steady_clock::time_point startTime, openTime, receivedTime, endTime;
+
+	shared_ptr<DataChannel> dc2;
+	pc2->onDataChannel(
+	    [&dc2, &finished, &receivedSize, &receivedTime, &endTime](shared_ptr<DataChannel> dc) {
+		    dc->onMessage([&receivedTime, &receivedSize](const variant<binary, string> &message) {
+			    if (holds_alternative<binary>(message)) {
+				    const auto &bin = get<binary>(message);
+				    if (receivedSize == 0)
+					    receivedTime = steady_clock::now();
+				    receivedSize += bin.size();
+			    }
+		    });
+
+		    dc->onClosed([&finished, &endTime]() {
+			    cout << "DataChannel closed." << endl;
+			    endTime = steady_clock::now();
+			    finished = true;
+		    });
+
+		    std::atomic_store(&dc2, dc);
+	    });
+
+	startTime = steady_clock::now();
+	auto dc1 = pc1->createDataChannel("benchmark");
+
+	dc1->onOpen([wdc1 = make_weak_ptr(dc1), &messageData, &openTime]() {
+		auto dc1 = wdc1.lock();
+		if (!dc1)
+			return;
+
+		openTime = steady_clock::now();
+
+		cout << "DataChannel open, sending data..." << endl;
+		while (dc1->bufferedAmount() == 0) {
+			dc1->send(messageData);
+		}
+
+		// When sent data is buffered in the DataChannel,
+		// wait for onBufferedAmountLow callback to continue
+	});
+
+	dc1->onBufferedAmountLow([wdc1 = make_weak_ptr(dc1), &messageData]() {
+		auto dc1 = wdc1.lock();
+		if (!dc1)
+			return;
+
+		// Continue sending
+		while (dc1->bufferedAmount() == 0) {
+			dc1->send(messageData);
+		}
+	});
+
+	const int steps = 10;
+	const auto stepDuration = duration / 10;
+	for (int i = 0; i < steps; ++i) {
+		this_thread::sleep_for(stepDuration);
+		cout << "Received: " << receivedSize.load() / 1000 << " KB" << endl;
+	}
+
+	if (auto adc2 = std::atomic_load(&dc2)) {
+		dc1->close();
+		while (!finished && adc2->isOpen())
+			this_thread::sleep_for(100ms);
+	}
+
+	auto connectDuration = duration_cast<milliseconds>(openTime - startTime);
+	auto transferDuration = duration_cast<milliseconds>(endTime - receivedTime);
+
+	cout << "Test duration: " << duration.count() << " ms" << endl;
+	cout << "Connect duration: " << connectDuration.count() << " ms" << endl;
+
+	size_t received = receivedSize.load();
+	size_t goodput = transferDuration.count() > 0 ? received / transferDuration.count() : 0;
+	cout << "Goodput: " << goodput * 0.001 << " MB/s"
+	     << " (" << goodput * 0.001 * 8 << " Mbit/s)" << endl;
+
+	pc1->close();
+	pc2->close();
+	this_thread::sleep_for(1s);
+
+	rtc::Cleanup();
+	return goodput;
+}
+
+#ifdef BENCHMARK_MAIN
+int main(int argc, char **argv) {
+	try {
+		size_t goodput = benchmark(30s);
+		if (goodput == 0)
+			throw runtime_error("No data received");
+
+		return 0;
+
+	} catch (const std::exception &e) {
+		cerr << "Benchmark failed: " << e.what() << endl;
+		return -1;
+	}
+}
+#endif

test/capi.cpp

@@ -0,0 +1,220 @@
+/**
+ * Copyright (c) 2020 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <rtc/rtc.h>
+
+#include <cstdbool>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+
+#ifdef _WIN32
+#include <windows.h>
+static void sleep(unsigned int secs) { Sleep(secs * 1000); }
+#else
+#include <unistd.h> // for sleep
+#endif
+
+typedef struct {
+	rtcState state;
+	rtcGatheringState gatheringState;
+	int pc;
+	int dc;
+	bool connected;
+} Peer;
+
+Peer *peer1 = NULL;
+Peer *peer2 = NULL;
+
+static void descriptionCallback(const char *sdp, const char *type, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	printf("Description %d:\n%s\n", peer == peer1 ? 1 : 2, sdp);
+	Peer *other = peer == peer1 ? peer2 : peer1;
+	rtcSetRemoteDescription(other->pc, sdp, type);
+}
+
+static void candidateCallback(const char *cand, const char *mid, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	printf("Candidate %d: %s\n", peer == peer1 ? 1 : 2, cand);
+	Peer *other = peer == peer1 ? peer2 : peer1;
+	rtcAddRemoteCandidate(other->pc, cand, mid);
+}
+
+static void stateChangeCallback(rtcState state, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	peer->state = state;
+	printf("State %d: %d\n", peer == peer1 ? 1 : 2, (int)state);
+}
+
+static void gatheringStateCallback(rtcGatheringState state, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	peer->gatheringState = state;
+	printf("Gathering state %d: %d\n", peer == peer1 ? 1 : 2, (int)state);
+}
+
+static void openCallback(void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	peer->connected = true;
+	printf("DataChannel %d: Open\n", peer == peer1 ? 1 : 2);
+
+	const char *message = peer == peer1 ? "Hello from 1" : "Hello from 2";
+	rtcSendMessage(peer->dc, message, -1); // negative size indicates a null-terminated string
+}
+
+static void closedCallback(void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	peer->connected = false;
+}
+
+static void messageCallback(const char *message, int size, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	if (size < 0) { // negative size indicates a null-terminated string
+		printf("Message %d: %s\n", peer == peer1 ? 1 : 2, message);
+	} else {
+		printf("Message %d: [binary of size %d]\n", peer == peer1 ? 1 : 2, size);
+	}
+}
+
+static void dataChannelCallback(int dc, void *ptr) {
+	Peer *peer = (Peer *)ptr;
+	peer->dc = dc;
+	peer->connected = true;
+	rtcSetClosedCallback(dc, closedCallback);
+	rtcSetMessageCallback(dc, messageCallback);
+
+	char buffer[256];
+	if (rtcGetDataChannelLabel(dc, buffer, 256) >= 0)
+		printf("DataChannel %d: Received with label \"%s\"\n", peer == peer1 ? 1 : 2, buffer);
+
+	const char *message = peer == peer1 ? "Hello from 1" : "Hello from 2";
+	rtcSendMessage(peer->dc, message, -1); // negative size indicates a null-terminated string
+}
+
+static Peer *createPeer(const rtcConfiguration *config) {
+	Peer *peer = (Peer *)malloc(sizeof(Peer));
+	if (!peer)
+		return nullptr;
+	memset(peer, 0, sizeof(Peer));
+
+	// Create peer connection
+	peer->pc = rtcCreatePeerConnection(config);
+	rtcSetUserPointer(peer->pc, peer);
+	rtcSetDataChannelCallback(peer->pc, dataChannelCallback);
+	rtcSetLocalDescriptionCallback(peer->pc, descriptionCallback);
+	rtcSetLocalCandidateCallback(peer->pc, candidateCallback);
+	rtcSetStateChangeCallback(peer->pc, stateChangeCallback);
+	rtcSetGatheringStateChangeCallback(peer->pc, gatheringStateCallback);
+
+	return peer;
+}
+
+static void deletePeer(Peer *peer) {
+	if (peer) {
+		if (peer->dc)
+			rtcDeleteDataChannel(peer->dc);
+		if (peer->pc)
+			rtcDeletePeerConnection(peer->pc);
+		free(peer);
+	}
+}
+
+int test_capi_main() {
+	int attempts;
+
+	rtcInitLogger(RTC_LOG_DEBUG);
+
+	// Create peer 1
+	rtcConfiguration config1;
+	memset(&config1, 0, sizeof(config1));
+	// STUN server example
+	// const char *iceServers[1] = {"stun:stun.l.google.com:19302"};
+	// config1.iceServers = iceServers;
+	// config1.iceServersCount = 1;
+
+	peer1 = createPeer(&config1);
+	if (!peer1)
+		goto error;
+
+	// Create peer 2
+	rtcConfiguration config2;
+	memset(&config2, 0, sizeof(config2));
+	// STUN server example
+	// config2.iceServers = iceServers;
+	// config2.iceServersCount = 1;
+	// Port range example
+	config2.portRangeBegin = 5000;
+	config2.portRangeEnd = 6000;
+
+	peer2 = createPeer(&config2);
+	if (!peer2)
+		goto error;
+
+	// Peer 1: Create data channel
+	peer1->dc = rtcCreateDataChannel(peer1->pc, "test");
+	rtcSetOpenCallback(peer1->dc, openCallback);
+	rtcSetClosedCallback(peer1->dc, closedCallback);
+	rtcSetMessageCallback(peer1->dc, messageCallback);
+
+	attempts = 10;
+	while (!peer2->connected && !peer1->connected && attempts--)
+		sleep(1);
+
+	if (peer1->state != RTC_CONNECTED || peer2->state != RTC_CONNECTED) {
+		fprintf(stderr, "PeerConnection is not connected\n");
+		goto error;
+	}
+
+	if (!peer1->connected || !peer2->connected) {
+		fprintf(stderr, "DataChannel is not connected\n");
+		goto error;
+	}
+
+	char buffer[256];
+	if (rtcGetLocalAddress(peer1->pc, buffer, 256) >= 0)
+		printf("Local address 1:  %s\n", buffer);
+	if (rtcGetRemoteAddress(peer1->pc, buffer, 256) >= 0)
+		printf("Remote address 1: %s\n", buffer);
+	if (rtcGetLocalAddress(peer2->pc, buffer, 256) >= 0)
+		printf("Local address 2:  %s\n", buffer);
+	if (rtcGetRemoteAddress(peer2->pc, buffer, 256) >= 0)
+		printf("Remote address 2: %s\n", buffer);
+
+	deletePeer(peer1);
+	sleep(1);
+	deletePeer(peer2);
+	sleep(1);
+
+	// You may call rtcCleanup() when finished to free static resources
+	rtcCleanup();
+	sleep(1);
+
+	printf("Success\n");
+	return 0;
+
+error:
+	deletePeer(peer1);
+	deletePeer(peer2);
+	return -1;
+}
+
+#include <stdexcept>
+
+void test_capi() {
+	if (test_capi_main())
+		throw std::runtime_error("Connection failed");
+}

test/connectivity.cpp

@@ -0,0 +1,156 @@
+/**
+ * Copyright (c) 2019 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "rtc/rtc.hpp"
+
+#include <atomic>
+#include <chrono>
+#include <iostream>
+#include <memory>
+#include <thread>
+
+using namespace rtc;
+using namespace std;
+
+template <class T> weak_ptr<T> make_weak_ptr(shared_ptr<T> ptr) { return ptr; }
+
+void test_connectivity() {
+	InitLogger(LogLevel::Debug);
+
+	Configuration config1;
+	// STUN server example
+	// config1.iceServers.emplace_back("stun:stun.l.google.com:19302");
+
+	auto pc1 = std::make_shared<PeerConnection>(config1);
+
+	Configuration config2;
+	// STUN server example
+	// config2.iceServers.emplace_back("stun:stun.l.google.com:19302");
+	// Port range example
+	config2.portRangeBegin = 5000;
+	config2.portRangeEnd = 6000;
+
+	auto pc2 = std::make_shared<PeerConnection>(config2);
+
+	pc1->onLocalDescription([wpc2 = make_weak_ptr(pc2)](const Description &sdp) {
+		auto pc2 = wpc2.lock();
+		if (!pc2)
+			return;
+		cout << "Description 1: " << sdp << endl;
+		pc2->setRemoteDescription(sdp);
+	});
+
+	pc1->onLocalCandidate([wpc2 = make_weak_ptr(pc2)](const Candidate &candidate) {
+		auto pc2 = wpc2.lock();
+		if (!pc2)
+			return;
+		cout << "Candidate 1: " << candidate << endl;
+		pc2->addRemoteCandidate(candidate);
+	});
+
+	pc1->onStateChange([](PeerConnection::State state) { cout << "State 1: " << state << endl; });
+
+	pc1->onGatheringStateChange([](PeerConnection::GatheringState state) {
+		cout << "Gathering state 1: " << state << endl;
+	});
+
+	pc2->onLocalDescription([wpc1 = make_weak_ptr(pc1)](const Description &sdp) {
+		auto pc1 = wpc1.lock();
+		if (!pc1)
+			return;
+		cout << "Description 2: " << sdp << endl;
+		pc1->setRemoteDescription(sdp);
+	});
+
+	pc2->onLocalCandidate([wpc1 = make_weak_ptr(pc1)](const Candidate &candidate) {
+		auto pc1 = wpc1.lock();
+		if (!pc1)
+			return;
+		cout << "Candidate 2: " << candidate << endl;
+		pc1->addRemoteCandidate(candidate);
+	});
+
+	pc2->onStateChange([](PeerConnection::State state) { cout << "State 2: " << state << endl; });
+
+	pc2->onGatheringStateChange([](PeerConnection::GatheringState state) {
+		cout << "Gathering state 2: " << state << endl;
+	});
+
+	shared_ptr<DataChannel> dc2;
+	pc2->onDataChannel([&dc2](shared_ptr<DataChannel> dc) {
+		cout << "DataChannel 2: Received with label \"" << dc->label() << "\"" << endl;
+
+		dc->onMessage([](const variant<binary, string> &message) {
+			if (holds_alternative<string>(message)) {
+				cout << "Message 2: " << get<string>(message) << endl;
+			}
+		});
+
+		dc->send("Hello from 2");
+
+		std::atomic_store(&dc2, dc);
+	});
+
+	auto dc1 = pc1->createDataChannel("test");
+	dc1->onOpen([wdc1 = make_weak_ptr(dc1)]() {
+		auto dc1 = wdc1.lock();
+		if (!dc1)
+			return;
+
+		cout << "DataChannel 1: Open" << endl;
+		dc1->send("Hello from 1");
+	});
+	dc1->onMessage([](const variant<binary, string> &message) {
+		if (holds_alternative<string>(message)) {
+			cout << "Message 1: " << get<string>(message) << endl;
+		}
+	});
+
+	int attempts = 10;
+	shared_ptr<DataChannel> adc2;
+	while ((!(adc2 = std::atomic_load(&dc2)) || !adc2->isOpen() || !dc1->isOpen()) && attempts--)
+		this_thread::sleep_for(1s);
+
+	if (pc1->state() != PeerConnection::State::Connected &&
+	    pc2->state() != PeerConnection::State::Connected)
+		throw runtime_error("PeerConnection is not connected");
+
+	if (!adc2 || !adc2->isOpen() || !dc1->isOpen())
+		throw runtime_error("DataChannel is not open");
+
+	if (auto addr = pc1->localAddress())
+		cout << "Local address 1:  " << *addr << endl;
+	if (auto addr = pc1->remoteAddress())
+		cout << "Remote address 1: " << *addr << endl;
+	if (auto addr = pc2->localAddress())
+		cout << "Local address 2:  " << *addr << endl;
+	if (auto addr = pc2->remoteAddress())
+		cout << "Remote address 2: " << *addr << endl;
+
+	// Delay close of peer 2 to check closing works properly
+	pc1->close();
+	this_thread::sleep_for(1s);
+	pc2->close();
+	this_thread::sleep_for(1s);
+
+	// You may call rtc::Cleanup() when finished to free static resources
+	rtc::Cleanup();
+	this_thread::sleep_for(1s);
+
+	cout << "Success" << endl;
+}

test/main.cpp

@@ -16,76 +16,62 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include "rtc/rtc.hpp"
-
 #include <chrono>
 #include <iostream>
-#include <memory>
-#include <thread>
 
-using namespace rtc;
 using namespace std;
+using namespace chrono_literals;
 
-int main(int argc, char **argv) {
+void test_connectivity();
-	rtc::Configuration config;
+void test_capi();
-	// config.iceServers.emplace_back("stun.l.google.com:19302");
+void test_websocket();
+size_t benchmark(chrono::milliseconds duration);
 
-	auto pc1 = std::make_shared<PeerConnection>(config);
+void test_benchmark() {
-	auto pc2 = std::make_shared<PeerConnection>(config);
+	size_t goodput = benchmark(10s);
 
-	pc1->onLocalDescription([pc2](const Description &sdp) {
+	if (goodput == 0)
-		cout << "Description 1: " << sdp << endl;
+		throw runtime_error("No data received");
-		pc2->setRemoteDescription(sdp);
-	});
 
-	pc1->onLocalCandidate([pc2](const Candidate &candidate) {
+	const size_t threshold = 1000; // 1 MB/s;
-		cout << "Candidate 1: " << candidate << endl;
+	if (goodput < threshold)
-		pc2->addRemoteCandidate(candidate);
+		throw runtime_error("Goodput is too low");
-	});
-
-	pc1->onStateChange([](PeerConnection::State state) { cout << "State 1: " << state << endl; });
-	pc1->onGatheringStateChange([](PeerConnection::GatheringState state) {
-		cout << "Gathering state 1: " << state << endl;
-	});
-
-	pc2->onLocalDescription([pc1](const Description &sdp) {
-		cout << "Description 2: " << sdp << endl;
-		pc1->setRemoteDescription(sdp);
-	});
-
-	pc2->onLocalCandidate([pc1](const Candidate &candidate) {
-		cout << "Candidate 2: " << candidate << endl;
-		pc1->addRemoteCandidate(candidate);
-	});
-
-	pc2->onStateChange([](PeerConnection::State state) { cout << "State 2: " << state << endl; });
-	pc2->onGatheringStateChange([](PeerConnection::GatheringState state) {
-		cout << "Gathering state 2: " << state << endl;
-	});
-
-	shared_ptr<DataChannel> dc2;
-	pc2->onDataChannel([&dc2](shared_ptr<DataChannel> dc) {
-		cout << "Got a DataChannel with label: " << dc->label() << endl;
-		dc2 = dc;
-		dc2->onMessage([](const variant<binary, string> &message) {
-			if (holds_alternative<string>(message)) {
-				cout << "Received 2: " << get<string>(message) << endl;
-			}
-		});
-		dc2->send("Hello from 2");
-	});
-
-	auto dc1 = pc1->createDataChannel("test");
-	dc1->onOpen([dc1]() {
-		cout << "DataChannel open: " << dc1->label() << endl;
-		dc1->send("Hello from 1");
-	});
-	dc1->onMessage([](const variant<binary, string> &message) {
-		if (holds_alternative<string>(message)) {
-			cout << "Received 1: " << get<string>(message) << endl;
-		}
-	});
-
-	this_thread::sleep_for(10s);
 }
 
+int main(int argc, char **argv) {
+	try {
+		cout << endl << "*** Running WebRTC connectivity test..." << endl;
+		test_connectivity();
+		cout << "*** Finished WebRTC connectivity test" << endl;
+	} catch (const exception &e) {
+		cerr << "WebRTC connectivity test failed: " << e.what() << endl;
+		return -1;
+	}
+	try {
+		cout << endl << "*** Running WebRTC C API test..." << endl;
+		test_capi();
+		cout << "*** Finished WebRTC C API test" << endl;
+	} catch (const exception &e) {
+		cerr << "WebRTC C API test failed: " << e.what() << endl;
+		return -1;
+	}
+#if RTC_ENABLE_WEBSOCKET
+	try {
+		cout << endl << "*** Running WebSocket test..." << endl;
+		test_websocket();
+		cout << "*** Finished WebSocket test" << endl;
+	} catch (const exception &e) {
+		cerr << "WebSocket test failed: " << e.what() << endl;
+		return -1;
+	}
+#endif
+	try {
+		cout << endl << "*** Running WebRTC benchmark..." << endl;
+		test_benchmark();
+		cout << "*** Finished WebRTC benchmark" << endl;
+	} catch (const exception &e) {
+		cerr << "WebRTC benchmark failed: " << e.what() << endl;
+		return -1;
+	}
+	return 0;
+}

test/websocket.cpp

@@ -0,0 +1,85 @@
+/**
+ * Copyright (c) 2019 Paul-Louis Ageneau
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "rtc/rtc.hpp"
+
+#if RTC_ENABLE_WEBSOCKET
+
+#include <chrono>
+#include <iostream>
+#include <memory>
+#include <thread>
+#include <atomic>
+
+using namespace rtc;
+using namespace std;
+
+template <class T> weak_ptr<T> make_weak_ptr(shared_ptr<T> ptr) { return ptr; }
+
+void test_websocket() {
+	InitLogger(LogLevel::Debug);
+
+	const string myMessage = "Hello world from libdatachannel";
+
+	auto ws = std::make_shared<WebSocket>();
+
+	ws->onOpen([wws = make_weak_ptr(ws), &myMessage]() {
+		auto ws = wws.lock();
+		if (!ws)
+			return;
+		cout << "WebSocket: Open" << endl;
+		ws->send(myMessage);
+	});
+
+	ws->onClosed([]() { cout << "WebSocket: Closed" << endl; });
+
+	std::atomic<bool> received = false;
+	ws->onMessage([&received, &myMessage](const variant<binary, string> &message) {
+		if (holds_alternative<string>(message)) {
+			string str = get<string>(message);
+			if((received = (str == myMessage)))
+				cout << "WebSocket: Received expected message" << endl;
+			else
+				cout << "WebSocket: Received UNEXPECTED message" << endl;
+		}
+	});
+
+	ws->open("wss://echo.websocket.org/");
+
+	int attempts = 10;
+	while ((!ws->isOpen() || !received) && attempts--)
+		this_thread::sleep_for(1s);
+
+	if (!ws->isOpen())
+		throw runtime_error("WebSocket is not open");
+
+	if(!received)
+		throw runtime_error("Expected message not received");
+
+	ws->close();
+	this_thread::sleep_for(1s);
+
+	// You may call rtc::Cleanup() when finished to free static resources
+	rtc::Cleanup();
+	this_thread::sleep_for(1s);
+
+	cout << "Success" << endl;
+}
+
+#endif
+