Bumped version to 0.7.1

Close data channels  asynchronously for safety

.github/FUNDING.yml

@@ -0,0 +1 @@
+custom: ['https://paypal.me/paullouisageneau']

.github/workflows/build-gnutls.yml

@@ -16,7 +16,7 @@ jobs:
     - name: submodules
       run: git submodule update --init --recursive
     - name: cmake
-      run: cmake -B build -DUSE_JUICE=1 -DUSE_GNUTLS=1
+      run: cmake -B build -DUSE_GNUTLS=1
     - name: make
       run: (cd build; make -j2)
     - name: test
@@ -30,7 +30,7 @@ jobs:
     - name: submodules
       run: git submodule update --init --recursive
     - name: cmake
-      run: cmake -B build -DUSE_JUICE=1 -DUSE_GNUTLS=1
+      run: cmake -B build -DUSE_GNUTLS=1
     - name: make
       run: (cd build; make -j2)
     - name: test

.github/workflows/build-nice.yml

@@ -16,7 +16,7 @@ jobs:
     - name: submodules
       run: git submodule update --init --recursive
     - name: cmake
-      run: cmake -B build -DUSE_JUICE=0 -DUSE_GNUTLS=1
+      run: cmake -B build -DUSE_GNUTLS=1 -DUSE_NICE=1
     - name: make
       run: (cd build; make -j2)
     - name: test

.github/workflows/build-openssl.yml

@@ -16,7 +16,7 @@ jobs:
     - name: submodules
       run: git submodule update --init --recursive
     - name: cmake
-      run: cmake -B build -DUSE_JUICE=1 -DUSE_GNUTLS=0
+      run: cmake -B build -DUSE_GNUTLS=0
     - name: make
       run: (cd build; make -j2)
     - name: test
@@ -30,7 +30,7 @@ jobs:
     - name: submodules
       run: git submodule update --init --recursive
     - name: cmake
-      run: cmake -B build -DUSE_JUICE=1 -DUSE_GNUTLS=0
+      run: cmake -B build -DUSE_GNUTLS=0
       env:
         OPENSSL_ROOT_DIR: /usr/local/opt/openssl
         OPENSSL_LIBRARIES: /usr/local/opt/openssl/lib
@@ -43,10 +43,12 @@ jobs:
     steps:
     - uses: actions/checkout@v2
     - uses: ilammy/msvc-dev-cmd@v1
+    - name: install packages
+      run: choco install openssl
     - name: submodules
       run: git submodule update --init --recursive
     - name: cmake
-      run: cmake -B build -G "NMake Makefiles" -DUSE_JUICE=1 -DUSE_GNUTLS=0
+      run: cmake -B build -G "NMake Makefiles" -DUSE_GNUTLS=0
     - name: nmake
       run: |
         cd build

CMakeLists.txt

@@ -1,12 +1,21 @@
 cmake_minimum_required(VERSION 3.7)
 project(libdatachannel
-	DESCRIPTION "WebRTC DataChannels Library"
-	VERSION 0.6.3
+	DESCRIPTION "WebRTC Data Channels Library"
+	VERSION 0.7.1
 	LANGUAGES CXX)
 
+# Options
 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)
+option(USE_NICE "Use libnice instead of libjuice" OFF)
+option(USE_SRTP "Enable SRTP for media support" OFF)
+option(NO_WEBSOCKET "Disable WebSocket support" OFF)
+option(NO_EXAMPLES "Disable examples" OFF)
+
+if(USE_NICE)
+	option(USE_JUICE "Use libjuice" OFF)
+else()
+	option(USE_JUICE "Use libjuice" ON)
+endif()
 
 if(USE_GNUTLS)
 	option(USE_NETTLE "Use Nettle instead of OpenSSL in libjuice" ON)
@@ -42,12 +51,15 @@ set(LIBDATACHANNEL_SOURCES
 	${CMAKE_CURRENT_SOURCE_DIR}/src/rtc.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/src/sctptransport.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/src/tls.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/threadpool.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/src/processor.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/verifiedtlstransport.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/src/websocket.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/src/wstransport.cpp
 )
@@ -82,11 +94,11 @@ set(TESTS_SOURCES
 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)
 
+option(sctp_build_programs 0)
 add_subdirectory(deps/usrsctp EXCLUDE_FROM_ALL)
 if (MSYS OR MINGW)
 	target_compile_definitions(usrsctp PUBLIC -DSCTP_STDINT_INCLUDE=<stdint.h>)
@@ -99,7 +111,14 @@ endif()
 add_library(Usrsctp::Usrsctp ALIAS usrsctp)
 add_library(Usrsctp::UsrsctpStatic ALIAS usrsctp-static)
 
-if (RTC_ENABLE_WEBSOCKET)
+if (NO_WEBSOCKET)
+	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)
+else()
 	add_library(datachannel SHARED
 		${LIBDATACHANNEL_SOURCES}
 		${LIBDATACHANNEL_WEBSOCKET_SOURCES})
@@ -108,13 +127,6 @@ if (RTC_ENABLE_WEBSOCKET)
 		${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
@@ -141,7 +153,8 @@ if(WIN32)
 	target_link_libraries(datachannel-static PRIVATE wsock32 ws2_32) # winsock2
 endif()
 
-if(SRTP_FOUND)
+if(USE_SRTP)
+	find_package(SRTP REQUIRED)
 	if(NOT TARGET SRTP::SRTP)
 		add_library(SRTP::SRTP UNKNOWN IMPORTED)
 		set_target_properties(SRTP::SRTP PROPERTIES
@@ -180,18 +193,18 @@ else()
 	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()
+if (USE_NICE OR NOT USE_JUICE)
 	find_package(LibNice REQUIRED)
-	target_compile_definitions(datachannel PRIVATE USE_JUICE=0)
-	target_compile_definitions(datachannel-static PRIVATE USE_JUICE=0)
+	target_compile_definitions(datachannel PRIVATE USE_NICE=1)
+	target_compile_definitions(datachannel-static PRIVATE USE_NICE=1)
 	target_link_libraries(datachannel PRIVATE LibNice::LibNice)
 	target_link_libraries(datachannel-static PRIVATE LibNice::LibNice)
+else()
+	add_subdirectory(deps/libjuice EXCLUDE_FROM_ALL)
+	target_compile_definitions(datachannel PRIVATE USE_NICE=0)
+	target_compile_definitions(datachannel-static PRIVATE USE_NICE=0)
+	target_link_libraries(datachannel PRIVATE LibJuice::LibJuiceStatic)
+	target_link_libraries(datachannel-static PRIVATE LibJuice::LibJuiceStatic)
 endif()
 
 add_library(LibDataChannel::LibDataChannel ALIAS datachannel)
@@ -228,9 +241,11 @@ else()
 endif()
 
 # 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)
+if(NOT NO_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)
+endif()
 

Jamfile

@@ -15,7 +15,7 @@ lib libdatachannel
 	: # requirements
 	<cxxstd>17
 	<include>./include/rtc
-	<define>USE_JUICE=1
+	<define>USE_NICE=0
 	<define>RTC_ENABLE_MEDIA=0
 	<define>RTC_ENABLE_WEBSOCKET=0
 	<toolset>msvc:<define>WIN32_LEAN_AND_MEAN
@@ -25,7 +25,7 @@ lib libdatachannel
 	<library>/libdatachannel//usrsctp
 	<library>/libdatachannel//juice
 	<library>/libdatachannel//plog
-	<gnutls>on:<library>gnutls
+	<gnutls>on:<library>gnutls/<link>shared
 	<gnutls>off:<library>ssl
 	<gnutls>off:<library>crypto
 	: # default build
@@ -69,8 +69,9 @@ alias juice
     : # no default build
     : # usage requirements
     <include>./deps/libjuice/include
-    <library>libjuice-static.a
-    <gnutls>on:<library>nettle
+    <gnutls>on:<library>libjuice-gnutls.a
+    <gnutls>on:<library>nettle/<link>shared
+    <gnutls>off:<library>libjuice-openssl.a
     ;
 
 alias juice
@@ -85,63 +86,84 @@ alias juice
 make libusrsctp.a : : @make_libusrsctp ;
 make usrsctp.lib : : @make_libusrsctp_msvc ;
 
+rule make_libusrsctp ( targets * : sources * : properties * )
+{
+	local VARIANT = [ feature.get-values <variant> : $(properties) ] ;
+	VARIANT on $(targets) = $(VARIANT) ;
+	BUILD_DIR on $(targets) = "build-$(VARIANT)" ;
+}
 actions make_libusrsctp
 {
-    (cd $(CWD)/deps/usrsctp && mkdir build && cd build && cmake -DCMAKE_C_FLAGS="-fPIC" .. && make -j2 usrsctp-static)
-    cp $(CWD)/deps/usrsctp/build/usrsctplib/libusrsctp.a $(<)
+    (cd $(CWD)/deps/usrsctp && mkdir -p $(BUILD_DIR) && cd $(BUILD_DIR) && cmake -DCMAKE_BUILD_TYPE=$(VARIANT) -DCMAKE_C_FLAGS="-fPIC -Wno-unknown-warning-option -Wno-format-truncation" .. && make -j2 usrsctp-static)
+    cp $(CWD)/deps/usrsctp/$(BUILD_DIR)/usrsctplib/libusrsctp.a $(<)
+}
+rule make_libusrsctp_msvc ( targets * : sources * : properties * )
+{
+	local VARIANT = [ feature.get-values <variant> : $(properties) ] ;
+	VARIANT on $(targets) = $(VARIANT) ;
+	BUILD_DIR on $(targets) = "build-$(VARIANT)" ;
 }
 actions make_libusrsctp_msvc
 {
 	SET OLDD=%CD%
     cd $(CWD)/deps/usrsctp
-    mkdir build
-    cd build
+    mkdir $(BUILD_DIR)
+    cd $(BUILD_DIR)
     cmake -G "Visual Studio 16 2019" ..
-    cd build
-    msbuild usrsctplib.sln /property:Configuration=Release
+    msbuild usrsctplib.sln /property:Configuration=$(VARIANT)
     cd %OLDD%
-    cp $(CWD)/deps/usrsctp/build/usrsctplib/Release/usrsctp.lib $(<)
+    cp $(CWD)/deps/usrsctp/$(BUILD_DIR)/usrsctplib/Release/usrsctp.lib $(<)
 }
 
-make libjuice-static.a : : @make_libjuice ;
+make libjuice-gnutls.a : : @make_libjuice_gnutls ;
+make libjuice-openssl.a : : @make_libjuice_openssl ;
 make juice-static.lib : : @make_libjuice_msvc ;
 
-rule make_libjuice ( targets * : sources * : properties * )
+rule make_libjuice_gnutls ( targets * : sources * : properties * )
 {
-	if <gnutls>on in $(properties)
-	{
-		CMAKEOPTS on $(targets) = "-DUSE_NETTLE=1" ;
-	}
-	else {
-		local OPENSSL_INCLUDE = [ feature.get-values <openssl-include> : $(properties) ] ;
-
-		if <target-os>darwin in $(properties) && $(OPENSSL_INCLUDE) = ""
-		{
-			# on macOS, default to pick up openssl from the homebrew installation
-			# brew install openssl
-			OPENSSL_INCLUDE = /usr/local/opt/openssl/include ;
-		}
-
-		CMAKEOPTS on $(targets) = "-DUSE_NETTLE=0" ;
-		if $(OPENSSL_INCLUDE) != ""
-		{
-			CMAKEOPTS on $(targets) += " -DOPENSSL_ROOT_DIR=$(OPENSSL_INCLUDE)/.." ;
-		}
-	}
+	local VARIANT = [ feature.get-values <variant> : $(properties) ] ;
+	BUILD_DIR on $(targets) = "build-gnutls-$(VARIANT)" ;
+	CMAKEOPTS on $(targets) = "-DCMAKE_C_FLAGS=\"-fPIC\" -DCMAKE_BUILD_TYPE=$(VARIANT) -DUSE_NETTLE=1" ;
 }
-actions make_libjuice
+actions make_libjuice_gnutls
 {
-    (cd $(CWD)/deps/libjuice && mkdir build && cd build && cmake -DCMAKE_C_FLAGS="-fPIC" $(CMAKEOPTS) .. && make -j2 juice-static)
-    cp $(CWD)/deps/libjuice/build/libjuice-static.a $(<)
+    (cd $(CWD)/deps/libjuice && mkdir -p $(BUILD_DIR) && cd $(BUILD_DIR) && cmake $(CMAKEOPTS) .. && make -j2 juice-static)
+    cp $(CWD)/deps/libjuice/$(BUILD_DIR)/libjuice-static.a $(<)
+}
+rule make_libjuice_openssl ( targets * : sources * : properties * )
+{
+	local VARIANT = [ feature.get-values <variant> : $(properties) ] ;
+	BUILD_DIR on $(targets) = "build-openssl-$(VARIANT)" ;
+	CMAKEOPTS on $(targets) = "-DCMAKE_C_FLAGS=\"-fPIC\" -DCMAKE_BUILD_TYPE=$(VARIANT) -DUSE_NETTLE=0" ;
+
+	local OPENSSL_INCLUDE = [ feature.get-values <openssl-include> : $(properties) ] ;
+	if <target-os>darwin in $(properties) && $(OPENSSL_INCLUDE) = ""
+	{
+		# on macOS, default to pick up openssl from the homebrew installation
+		# brew install openssl
+		OPENSSL_INCLUDE = /usr/local/opt/openssl/include ;
+	}
+
+	if $(OPENSSL_INCLUDE) != ""
+	{ CMAKEOPTS on $(targets) += " -DOPENSSL_ROOT_DIR=$(OPENSSL_INCLUDE)/.." ; }
+}
+actions make_libjuice_openssl
+{
+    (cd $(CWD)/deps/libjuice && mkdir -p $(BUILD_DIR) && cd $(BUILD_DIR) && cmake $(CMAKEOPTS) .. && make -j2 juice-static)
+    cp $(CWD)/deps/libjuice/$(BUILD_DIR)/libjuice-static.a $(<)
 }
 rule make_libjuice_msvc ( targets * : sources * : properties * )
 {
+	local VARIANT = [ feature.get-values <variant> : $(properties) ] ;
+	VARIANT on $(targets) = $(VARIANT) ;
 	if <gnutls>on in $(properties)
 	{
+		BUILD_DIR on $(targets) += "build-gnutls-$(VARIANT)" ;
 		CMAKEOPTS on $(targets) = "-DUSE_NETTLE=1" ;
 	}
 	else
 	{
+		BUILD_DIR on $(targets) += "build-openssl-$(VARIANT)" ;
 		CMAKEOPTS on $(targets) = "-DUSE_NETTLE=0" ;
 	}
 }
@@ -149,12 +171,12 @@ actions make_libjuice_msvc
 {
 	SET OLDD=%CD%
     cd $(CWD)/deps/libjuice
-    mkdir build
-    cd build
+    mkdir $(BUILD_DIR)
+    cd $(BUILD_DIR)
     cmake -G "Visual Studio 16 2019" $(CMAKEOPTS) ..
-    msbuild libjuice.sln /property:Configuration=Release
+    msbuild libjuice.sln /property:Configuration=$(VARIANT)
     cd %OLDD%
-    cp $(CWD)/deps/libjuice/build/Release/juice-static.lib $(<)
+    cp $(CWD)/deps/libjuice/$(BUILD_DIR)/Release/juice-static.lib $(<)
 }
 
 # the search path to pick up the openssl libraries from. This is the <search>

Makefile

@@ -25,35 +25,35 @@ else
         LIBS+=openssl
 endif
 
-USE_JUICE ?= 0
-ifneq ($(USE_JUICE), 0)
-        CPPFLAGS+=-DUSE_JUICE=1
+USE_NICE ?= 0
+ifneq ($(USE_NICE), 0)
+        CPPFLAGS+=-DUSE_NICE=1
+        LIBS+=glib-2.0 gobject-2.0 nice
+else
+        CPPFLAGS+=-DUSE_NICE=0
         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 ($(RTC_ENABLE_MEDIA), 0)
+USE_SRTP ?= 0
+ifneq ($(USE_SRTP), 0)
         CPPFLAGS+=-DRTC_ENABLE_MEDIA=1
         LIBS+=srtp
 else
         CPPFLAGS+=-DRTC_ENABLE_MEDIA=0
 endif
 
-RTC_ENABLE_WEBSOCKET ?= 1
-ifneq ($(RTC_ENABLE_WEBSOCKET), 0)
+
+NO_WEBSOCKET ?= 0
+ifeq ($(NO_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))
 

README.md

@@ -2,7 +2,7 @@
 
 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 security layer can be provided through [OpenSSL](https://www.openssl.org/) or [GnuTLS](https://www.gnutls.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.
@@ -47,14 +47,14 @@ Features:
 Dependencies:
 - GnuTLS: https://www.gnutls.org/ or OpenSSL: https://www.openssl.org/
 
-Optional dependencies:
-- libnice: https://nice.freedesktop.org/ (substituable with libjuice)
-- libSRTP: https://github.com/cisco/libsrtp (only necessary for media transport)
-
 Submodules:
 - libjuice: https://github.com/paullouisageneau/libjuice
 - usrsctp: https://github.com/sctplab/usrsctp
 
+Optional dependencies:
+- libnice: https://nice.freedesktop.org/ (only if selected as ICE backend instead of libjuice)
+- libSRTP: https://github.com/cisco/libsrtp (only necessary for supporting media transport)
+
 ## Building
 
 ### Clone repository and submodules
@@ -67,33 +67,37 @@ $ git submodule update --init --recursive
 
 ### Building with CMake
 
-The CMake library targets `libdatachannel` and `libdatachannel-static` respectively correspond to the shared and static libraries. On Windows, the DLL resulting from the shared library build only exposes the C API, use the static library for the C++ API. The default target will build tests and examples.
+The CMake library targets `libdatachannel` and `libdatachannel-static` respectively correspond to the shared and static libraries. The default target will build tests and examples. The option `USE_GNUTLS` allows to switch between OpenSSL (default) and GnuTLS, and the option `USE_NICE` allows to switch between libjuice as submodule (default) and libnice.
+
+On Windows, the DLL resulting from the shared library build only exposes the C API, use the static library for the C++ API.
 
 #### POSIX-compliant operating systems (including Linux and Apple macOS)
 ```bash
-$ cmake -B build -DUSE_JUICE=1 -DUSE_GNUTLS=1
+$ cmake -B build -DUSE_GNUTLS=1 -DUSE_NICE=0
 $ cd build
 $ make -j2
 ```
 
 #### Microsoft Windows with MinGW cross-compilation
 ```bash
-$ cmake -B build -DUSE_JUICE=1 -DCMAKE_TOOLCHAIN_FILE=/usr/share/mingw/toolchain-x86_64-w64-mingw32.cmake # replace with your toolchain file
+$ cmake -B build -DCMAKE_TOOLCHAIN_FILE=/usr/share/mingw/toolchain-x86_64-w64-mingw32.cmake # replace with your toolchain file
 $ cd build
 $ make -j2
 ```
 
 #### Microsoft Windows with Microsoft Visual C++
 ```bash
-$ cmake -B build -G "NMake Makefiles" -DUSE_JUICE=1
+$ cmake -B build -G "NMake Makefiles"
 $ cd build
 $ nmake
 ```
 
 ### Building directly with Make (Linux only)
 
+The option `USE_GNUTLS` allows to switch between OpenSSL (default) and GnuTLS, and the option `USE_NICE` allows to switch between libjuice as submodule (default) and libnice.
+
 ```bash
-$ make USE_JUICE=1 USE_GNUTLS=1
+$ make USE_GNUTLS=1 USE_NICE=0
 ```
 
 ## Examples
@@ -192,3 +196,7 @@ ws->open("wss://my.websocket/service");
 
 ```
 
+## External resources
+- Rust wrappers for libdatachannel: [datachannel-rs](https://github.com/lerouxrgd/datachannel-rs)
+- WebAssembly wrappers compatible with libdatachannel: [datachannel-wasm](https://github.com/paullouisageneau/datachannel-wasm)
+

examples/README.md

@@ -1,10 +1,11 @@
 # Examples for libdatachannel
 
-This directory contains different WebRTC clients and WebSocket + JSON signaling servers.
+This directory contains different WebRTC clients and compatible 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
+- [signaling-server-rust](signaling-server-rust) contains a similar signaling server in Rust (see [lerouxrgd/datachannel-rs](https://github.com/lerouxrgd/datachannel-rs) for Rust wrappers)
 
 Additionally, it contains two debugging tools for libdatachannel with copy-pasting as signaling:
 - [copy-paste](copy-paste) using the C++ API

examples/client/main.cpp

@@ -49,7 +49,7 @@ shared_ptr<PeerConnection> createPeerConnection(const Configuration &config,
 string randomId(size_t length);
 
 int main(int argc, char **argv) {
-	rtc::InitLogger(LogLevel::Warning);
+	rtc::InitLogger(LogLevel::Debug);
 
 	Configuration config;
 	config.iceServers.emplace_back("stun:stun.l.google.com:19302"); // change to your STUN server

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

@@ -1,6 +1,6 @@
 #!/usr/bin/env python
 #
-# Signaling server example for libdatachannel
+# Python signaling server example for libdatachannel
 # Copyright (c) 2020 Paul-Louis Ageneau
 #
 # This program is free software: you can redistribute it and/or modify

examples/signaling-server-rust/Cargo.toml

@@ -1,18 +1,14 @@
 [package]
-name = "webrtc_server"
+name = "libdatachannel_signaling_server_example"
 version = "0.1.0"
-authors = ["Nico Chatzi <nico.chatzigianis@focusrite.com>"]
+authors = ["Paul-Louis Ageneau"]
 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"
+tokio = { version = "*", features = ["full"] }
+tungstenite = "*"
+tokio-tungstenite = "*"
+futures-util = "*"
+futures-channel = "*"
+json = "*"
 
-[dependencies.rocket_contrib]
-version = "0.4.4"
-default-features = false
-features = ["json"]

examples/signaling-server-rust/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
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+
+                            Preamble
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+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
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+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.
+
+    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/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source.  For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code.  There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+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-rust/src/main.rs

@@ -1,147 +1,108 @@
-#![feature(proc_macro_hygiene, decl_macro)]
+/*
+ * Rust 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/>.
+ */
 
-#[macro_use]
-extern crate rocket;
-extern crate rocket_cors;
-#[macro_use]
-extern crate rocket_contrib;
-#[macro_use]
-extern crate serde_derive;
+extern crate tokio;
+extern crate tungstenite;
+extern crate futures_util;
+extern crate futures_channel;
+extern crate json;
 
-extern crate bincode;
+use std::env;
+use std::collections::HashMap;
+use std::sync::{Arc, Mutex};
 
-use std::sync::Mutex;
+use tokio::net::{TcpListener, TcpStream};
+use tungstenite::protocol::Message;
+use tungstenite::handshake::server::{Request, Response};
 
-use rocket_contrib::json::{Json, JsonValue};
+use futures_util::{future, pin_mut, StreamExt};
+use futures_util::stream::TryStreamExt;
+use futures_channel::mpsc;
 
-use rocket::http::Method; // 1.
+type Id = String;
+type Tx = mpsc::UnboundedSender<Message>;
+type ClientsMap = Arc<Mutex<HashMap<Id, Tx>>>;
 
-use rocket_cors::{
-    AllowedHeaders, AllowedOrigins, Error, // 2.
-    Cors, CorsOptions // 3.
-};
+async fn handle(clients: ClientsMap, stream: TcpStream) {
+    let mut client_id = Id::new();
+    let callback = |req: &Request, response: Response| {
+        let path: &str = req.uri().path();
+        let tokens: Vec<&str> = path.split('/').collect();
+        client_id = tokens[1].to_string();
+        return Ok(response);
+    };
 
-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",
-    ]);
+    let websocket = tokio_tungstenite::accept_hdr_async(stream, callback)
+        .await.expect("WebSocket handshake failed");
+	println!("Client {} connected", &client_id);
 
-    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")
-}
+    let (tx, rx) = mpsc::unbounded();
+    clients.lock().unwrap().insert(client_id.clone(), tx);
 
-type Data = Mutex<String>;
+    let (outgoing, incoming) = websocket.split();
+    let forward = rx.map(Ok).forward(outgoing);
+    let process = incoming.try_for_each(|msg| {
+        if msg.is_text() {
+            let text = msg.to_text().unwrap();
+            println!("Client {} << {}", &client_id, &text);
 
-#[derive(Serialize, Deserialize, Clone, PartialEq, Debug)]
-pub struct ChannelData {
-    pub description: String,
-    pub candidate: String,
-}
+            // Parse
+            let mut content = json::parse(text).unwrap();
+            let remote_id = content["id"].to_string();
+            let mut locked = clients.lock().unwrap();
 
-impl Default for ChannelData {
-    fn default() -> ChannelData {
-        ChannelData {
-            description: "".to_owned(),
-            candidate: "".to_owned(),
+            match locked.get_mut(&remote_id) {
+                Some(remote) => {
+                    // Format
+                    content.insert("id", client_id.clone()).unwrap();
+                    let text = json::stringify(content);
+
+                    // Send to remote
+                    println!("Client {} >> {}", &remote_id, &text);
+                    remote.unbounded_send(Message::text(text)).unwrap();
+                },
+                _ => println!("Client {} not found", &remote_id),
+            }
         }
+        future::ok(())
+    });
+
+    pin_mut!(process, forward);
+    future::select(process, forward).await;
+
+    println!("Client {} disconnected", &client_id);
+    clients.lock().unwrap().remove(&client_id);
+}
+
+#[tokio::main]
+async fn main() -> Result<(), std::io::Error> {
+    let service = env::args().nth(1).unwrap_or("8000".to_string());
+    let endpoint = format!("127.0.0.1:{}", service);
+
+    let mut listener = TcpListener::bind(endpoint)
+    	.await.expect("Listener binding failed");
+
+    let clients = ClientsMap::new(Mutex::new(HashMap::new()));
+
+    while let Ok((stream, _)) = listener.accept().await {
+        tokio::spawn(handle(clients.clone(), stream));
     }
+
+    return Ok(())
 }
 
-#[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);
-    }
-}

include/rtc/description.hpp

@@ -49,6 +49,7 @@ public:
 	bool ended() const;
 
 	void hintType(Type type);
+	void setDataMid(string mid);
 	void setFingerprint(string fingerprint);
 	void setSctpPort(uint16_t port);
 	void setMaxMessageSize(size_t size);
@@ -86,7 +87,7 @@ private:
 		string mid;
 		std::vector<string> attributes;
 	};
-	std::map<string, Media> mMedia; // by mid
+	std::map<int, Media> mMedia; // by m-line index
 
 	// Candidates
 	std::vector<Candidate> mCandidates;

include/rtc/include.hpp

@@ -64,6 +64,8 @@ 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
 
+const int THREADPOOL_SIZE = 4; // Number of threads in the global thread pool
+
 // overloaded helper
 template <class... Ts> struct overloaded : Ts... { using Ts::operator()...; };
 template <class... Ts> overloaded(Ts...)->overloaded<Ts...>;
@@ -82,9 +84,24 @@ template <typename F, typename T, typename... Args> auto weak_bind(F &&f, T *t,
 template <typename... P> class synchronized_callback {
 public:
 	synchronized_callback() = default;
+	synchronized_callback(synchronized_callback &&cb) { *this = std::move(cb); }
+	synchronized_callback(const synchronized_callback &cb) { *this = cb; }
 	synchronized_callback(std::function<void(P...)> func) { *this = std::move(func); }
 	~synchronized_callback() { *this = nullptr; }
 
+	synchronized_callback &operator=(synchronized_callback &&cb) {
+		std::scoped_lock lock(mutex, cb.mutex);
+		callback = std::move(cb.callback);
+		cb.callback = nullptr;
+		return *this;
+	}
+
+	synchronized_callback &operator=(const synchronized_callback &cb) {
+		std::scoped_lock lock(mutex, cb.mutex);
+		callback = cb.callback;
+		return *this;
+	}
+
 	synchronized_callback &operator=(std::function<void(P...)> func) {
 		std::lock_guard lock(mutex);
 		callback = std::move(func);

include/rtc/init.hpp

@@ -25,8 +25,7 @@
 
 namespace rtc {
 
-class Init;
-using init_token = std::shared_ptr<Init>;
+using init_token = std::shared_ptr<void>;
 
 class Init {
 public:
@@ -39,9 +38,10 @@ public:
 private:
 	Init();
 
-	static std::weak_ptr<Init> Weak;
-	static init_token Global;
-	static std::mutex Mutex;
+	static std::weak_ptr<void> Weak;
+	static std::shared_ptr<void> *Global;
+	static bool Initialized;
+	static std::recursive_mutex Mutex;
 };
 
 inline void Preload() { Init::Preload(); }

include/rtc/message.hpp

@@ -37,6 +37,8 @@ struct Message : binary {
 	Message(Iterator begin_, Iterator end_, Type type_ = Binary)
 	    : binary(begin_, end_), type(type_) {}
 
+	Message(binary &&data, Type type_ = Binary) : binary(std::move(data)), type(type_) {}
+
 	Type type;
 	unsigned int stream = 0;
 	std::shared_ptr<Reliability> reliability;
@@ -68,6 +70,15 @@ inline message_ptr make_message(size_t size, Message::Type type = Message::Binar
 	return message;
 }
 
+inline message_ptr make_message(binary &&data, Message::Type type = Message::Binary,
+                                unsigned int stream = 0,
+                                std::shared_ptr<Reliability> reliability = nullptr) {
+	auto message = std::make_shared<Message>(std::move(data), type);
+	message->stream = stream;
+	message->reliability = reliability;
+	return message;
+}
+
 } // namespace rtc
 
 #endif

include/rtc/peerconnection.hpp

@@ -41,6 +41,7 @@
 namespace rtc {
 
 class Certificate;
+class Processor;
 class IceTransport;
 class DtlsTransport;
 class SctpTransport;
@@ -101,7 +102,7 @@ public:
 	// Media
 	bool hasMedia() const;
 	void sendMedia(const binary &packet);
-	void send(const byte *packet, size_t size);
+	void sendMedia(const byte *packet, size_t size);
 
 	void onMedia(std::function<void(const binary &packet)> callback);
 
@@ -139,10 +140,10 @@ private:
 
 	void outgoingMedia(message_ptr message);
 
+	const init_token mInitToken = Init::Token();
 	const Configuration mConfig;
 	const future_certificate_ptr mCertificate;
-
-	init_token mInitToken = Init::Token();
+	const std::unique_ptr<Processor> mProcessor;
 
 	std::optional<Description> mLocalDescription, mRemoteDescription;
 	mutable std::mutex mLocalDescriptionMutex, mRemoteDescriptionMutex;

include/rtc/rtc.h

@@ -37,6 +37,7 @@ extern "C" {
 #define RTC_ENABLE_WEBSOCKET 1
 #endif
 
+#include <stdbool.h>
 #include <stdint.h>
 
 // libdatachannel C API
@@ -120,7 +121,12 @@ RTC_EXPORT int rtcGetDataChannelLabel(int dc, char *buffer, int size);
 
 // WebSocket
 #if RTC_ENABLE_WEBSOCKET
+typedef struct {
+	bool disableTlsVerification; // if true, don't verify the TLS certificate
+} rtcWsConfiguration;
+
 RTC_EXPORT int rtcCreateWebSocket(const char *url); // returns ws id
+RTC_EXPORT int rtcCreateWebSocketEx(const char *url, const rtcWsConfiguration *config);
 RTC_EXPORT int rtcDeleteWebsocket(int ws);
 #endif
 

include/rtc/websocket.hpp

@@ -47,7 +47,11 @@ public:
 		Closed = 3,
 	};
 
-	WebSocket();
+	struct Configuration {
+		bool disableTlsVerification = false; // if true, don't verify the TLS certificate
+	};
+
+	WebSocket(std::optional<Configuration> config = nullopt);
 	~WebSocket();
 
 	State readyState() const;
@@ -82,6 +86,7 @@ private:
 	std::shared_ptr<WsTransport> mWsTransport;
 	std::recursive_mutex mInitMutex;
 
+	const Configuration mConfig;
 	string mScheme, mHost, mHostname, mService, mPath;
 	std::atomic<State> mState = State::Closed;
 

src/candidate.cpp

@@ -28,6 +28,7 @@
 #else
 #include <netdb.h>
 #include <sys/socket.h>
+#include <netinet/in.h>
 #endif
 
 #include <sys/types.h>
@@ -107,8 +108,9 @@ bool Candidate::resolve(ResolveMode mode) {
 						oss << sp << nodebuffer << sp << servbuffer << sp << "typ" << sp << type;
 						oss << left;
 						mCandidate = oss.str();
+						mIsResolved = true;
 						PLOG_VERBOSE << "Resolved candidate: " << mCandidate;
-						return mIsResolved = true;
+						break;
 					}
 				}
 		}
@@ -116,7 +118,7 @@ bool Candidate::resolve(ResolveMode mode) {
 		freeaddrinfo(result);
 	}
 
-	return false;
+	return mIsResolved;
 }
 
 bool Candidate::isResolved() const { return mIsResolved; }

src/certificate.cpp

@@ -17,6 +17,7 @@
  */
 
 #include "certificate.hpp"
+#include "threadpool.hpp"
 
 #include <cassert>
 #include <chrono>
@@ -201,8 +202,8 @@ certificate_ptr make_certificate_impl(string commonName) {
 	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) ||
+	if (!X509_gmtime_adj(X509_getm_notBefore(x509.get()), 3600 * -1) ||
+	    !X509_gmtime_adj(X509_getm_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())) ||
@@ -230,19 +231,6 @@ 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::invoke_result_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;
 
@@ -254,7 +242,7 @@ future_certificate_ptr make_certificate(string commonName) {
 	if (auto it = CertificateCache.find(commonName); it != CertificateCache.end())
 		return it->second;
 
-	auto future = thread_call(make_certificate_impl, commonName);
+	auto future = ThreadPool::Instance().enqueue(make_certificate_impl, commonName);
 	auto shared = future.share();
 	CertificateCache.emplace(std::move(commonName), shared);
 	return shared;

src/datachannel.cpp

@@ -96,7 +96,7 @@ void DataChannel::close() {
 	mIsClosed = true;
 	if (mIsOpen.exchange(false))
 		if (auto transport = mSctpTransport.lock())
-			transport->close(mStream);
+			transport->closeStream(mStream);
 
 	mSctpTransport.reset();
 	resetCallbacks();

src/description.cpp

@@ -63,6 +63,7 @@ Description::Description(const string &sdp, Type type, Role role)
 	std::istringstream ss(sdp);
 	std::optional<Media> currentMedia;
 
+	int mlineIndex = 0;
 	bool finished;
 	do {
 		string line;
@@ -76,7 +77,9 @@ Description::Description(const string &sdp, Type type, Role role)
 					if (currentMedia->type == "application")
 						mData.mid = currentMedia->mid;
 					else
-						mMedia.emplace(currentMedia->mid, std::move(*currentMedia));
+						mMedia.emplace(mlineIndex, std::move(*currentMedia));
+
+					++mlineIndex;
 
 				} else if (line.find(" ICE/SDP") != string::npos) {
 					PLOG_WARNING << "SDP \"m=\" line has no corresponding mid, ignoring";
@@ -163,6 +166,8 @@ void Description::hintType(Type type) {
 	}
 }
 
+void Description::setDataMid(string mid) { mData.mid = mid; }
+
 void Description::setFingerprint(string fingerprint) {
 	mFingerprint.emplace(std::move(fingerprint));
 }
@@ -188,10 +193,7 @@ bool Description::hasMedia() const { return !mMedia.empty(); }
 
 void Description::addMedia(const Description &source) {
 	for (auto p : source.mMedia)
-		if (p.first != mData.mid)
-			mMedia.emplace(std::move(p));
-		else
-			PLOG_WARNING << "Media mid \"" << p.first << "\" is the same as data mid, ignoring";
+		mMedia.emplace(p);
 }
 
 Description::operator string() const { return generateSdp("\r\n"); }
@@ -212,48 +214,60 @@ string Description::generateSdp(const string &eol) const {
 	// 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 &m : mMedia)
-		sdp << " " << m.first; // mid
-	sdp << " " << mData.mid << eol;
+	for (int i = 0; i < int(mMedia.size() + 1); ++i)
+		if (auto it = mMedia.find(i); it != mMedia.end())
+			sdp << ' ' << it->second.mid;
+		else
+			sdp << ' ' << mData.mid;
+	sdp << 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;
+	sdp << "a=msid-semantic: WMS" << eol;
 
 	// Non-data media
 	if (!mMedia.empty()) {
 		// Lip-sync
 		sdp << "a=group:LS";
-		for (const auto &m : mMedia)
-			sdp << " " << m.first; // mid
+		for (const auto &p : mMedia)
+			sdp << " " << p.second.mid;
 		sdp << eol;
+	}
 
-		// Descriptions and attributes
-		for (const auto &m : mMedia) {
-			const auto &media = m.second;
+	// Descriptions and attributes
+	for (int i = 0; i < int(mMedia.size() + 1); ++i) {
+		if (auto it = mMedia.find(i); it != mMedia.end()) {
+			// Non-data media
+			const auto &media = it->second;
 			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;
+
+		} else {
+			// Data
+			const string description = "UDP/DTLS/SCTP webrtc-datachannel";
+			sdp << "m=application" << ' ' << (!mMedia.empty() ? 0 : 9) << ' ' << description << 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;
 		}
 	}
 
 	// Common
-	sdp << "a=ice-options:trickle" << eol;
+	if (!mEnded)
+		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=tls-id:1" << eol;
+
 	if (mFingerprint)
 		sdp << "a=fingerprint:sha-256 " << *mFingerprint << eol;
 

src/dtlssrtptransport.cpp

@@ -43,50 +43,86 @@ DtlsSrtpTransport::DtlsSrtpTransport(std::shared_ptr<IceTransport> lower,
                     std::move(stateChangeCallback)),
       mSrtpRecvCallback(std::move(srtpRecvCallback)) { // distinct from Transport recv callback
 
-	PLOG_DEBUG << "Initializing SRTP transport";
+	PLOG_DEBUG << "Initializing DTLS-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
+	if (srtp_err_status_t err = srtp_create(&mSrtpIn, nullptr)) {
+		throw std::runtime_error("SRTP create failed, status=" + to_string(static_cast<int>(err)));
+	}
+	if (srtp_err_status_t err = srtp_create(&mSrtpOut, nullptr)) {
+		srtp_dealloc(mSrtpIn);
+		throw std::runtime_error("SRTP create failed, status=" + to_string(static_cast<int>(err)));
+	}
 }
 
 DtlsSrtpTransport::~DtlsSrtpTransport() {
 	stop();
 
-	if (mCreated)
-		srtp_dealloc(mSrtp);
+	srtp_dealloc(mSrtpIn);
+	srtp_dealloc(mSrtpOut);
 }
 
-bool DtlsSrtpTransport::send(message_ptr message) {
+bool DtlsSrtpTransport::sendMedia(message_ptr message) {
 	if (!message)
 		return false;
 
+	if (!mInitDone) {
+		PLOG_WARNING << "SRTP media sent before keys are derived";
+		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.
+	// The RTP header has a minimum size of 12 bytes
+	if (size < 12)
+		throw std::runtime_error("RTP/RTCP packet too short");
+
+	// srtp_protect() and srtp_protect_rtcp() assume that they 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)));
+
+	uint8_t value2 = to_integer<uint8_t>(*(message->begin() + 1)) & 0x7F;
+	PLOG_VERBOSE << "Demultiplexing SRTCP and SRTP with RTP payload type, value="
+	             << unsigned(value2);
+
+	// RFC 5761 Multiplexing RTP and RTCP 4. Distinguishable RTP and RTCP Packets
+	// It is RECOMMENDED to follow the guidelines in the RTP/AVP profile for the choice of RTP
+	// payload type values, with the additional restriction that payload type values in the
+	// range 64-95 MUST NOT be used. Specifically, dynamic RTP payload types SHOULD be chosen in
+	// the range 96-127 where possible. Values below 64 MAY be used if that is insufficient
+	// [...]
+	if (value2 >= 64 && value2 <= 95) { // Range 64-95 (inclusive) MUST be RTCP
+		if (srtp_err_status_t err = srtp_protect_rtcp(mSrtpOut, message->data(), &size)) {
+			if (err == srtp_err_status_replay_fail)
+				throw std::runtime_error("SRTCP packet is a replay");
+			else
+				throw std::runtime_error("SRTCP protect error, status=" +
+				                         to_string(static_cast<int>(err)));
+		}
+		PLOG_VERBOSE << "Protected SRTCP packet, size=" << size;
+	} else {
+		if (srtp_err_status_t err = srtp_protect(mSrtpOut, 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;
 	}
-	PLOG_VERBOSE << "Protected SRTP packet, size=" << size;
+
 	message->resize(size);
 	outgoing(message);
 	return true;
 }
 
 void DtlsSrtpTransport::incoming(message_ptr message) {
+	if (!mInitDone) {
+		// Bypas
+		DtlsTransport::incoming(message);
+		return;
+	}
+
 	int size = message->size();
 	if (size == 0)
 		return;
@@ -95,49 +131,80 @@ void DtlsSrtpTransport::incoming(message_ptr message) {
 	// 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());
+	uint8_t value1 = to_integer<uint8_t>(*message->begin());
+	PLOG_VERBOSE << "Demultiplexing DTLS and SRTP/SRTCP with first byte, value="
+	             << unsigned(value1);
 
-	if (value >= 128 && value <= 192) {
+	if (value1 >= 20 && value1 <= 63) {
 		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;
+	} else if (value1 >= 128 && value1 <= 191) {
+		// The RTP header has a minimum size of 12 bytes
+		if (size < 12) {
+			PLOG_WARNING << "Incoming SRTP/SRTCP packet too short, size=" << size;
 			return;
 		}
-		PLOG_VERBOSE << "Unprotected SRTP packet, size=" << size;
+
+		uint8_t value2 = to_integer<uint8_t>(*(message->begin() + 1)) & 0x7F;
+		PLOG_VERBOSE << "Demultiplexing SRTCP and SRTP with RTP payload type, value="
+		             << unsigned(value2);
+
+		// See RFC 5761 reference above
+		if (value2 >= 64 && value2 <= 95) { // Range 64-95 (inclusive) MUST be RTCP
+			PLOG_VERBOSE << "Incoming SRTCP packet, size=" << size;
+			if (srtp_err_status_t err = srtp_unprotect_rtcp(mSrtpIn, message->data(), &size)) {
+				if (err == srtp_err_status_replay_fail)
+					PLOG_WARNING << "Incoming SRTCP packet is a replay";
+				else
+					PLOG_WARNING << "SRTCP unprotect error, status=" << err;
+				return;
+			}
+			PLOG_VERBOSE << "Unprotected SRTCP packet, size=" << size;
+		} else {
+			PLOG_VERBOSE << "Incoming SRTP packet, size=" << size;
+			if (srtp_err_status_t err = srtp_unprotect(mSrtpIn, 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;
+		PLOG_WARNING << "Unknown packet type, value=" << unsigned(value1) << ", size=" << size;
 	}
 }
 
+void DtlsSrtpTransport::postCreation() {
+#if USE_GNUTLS
+	PLOG_DEBUG << "Setting SRTP profile (GnuTLS)";
+	gnutls::check(gnutls_srtp_set_profile(mSession, GNUTLS_SRTP_AES128_CM_HMAC_SHA1_80),
+	              "Failed to set SRTP profile");
+#else
+	PLOG_DEBUG << "Setting SRTP profile (OpenSSL)";
+	// returns 0 on success, 1 on error
+	if (SSL_set_tlsext_use_srtp(mSsl, "SRTP_AES128_CM_SHA1_80"), "Failed to set SRTP profile")
+		throw std::runtime_error("Failed to set SRTP profile: " + openssl::error_string(ERR_get_error()));
+#endif
+}
+
 void DtlsSrtpTransport::postHandshake() {
-	if (mCreated)
+	if (mInitDone)
 		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
+	PLOG_INFO << "Deriving SRTP keying material (GnuTLS)";
+
 	gnutls_datum_t clientKeyDatum, clientSaltDatum, serverKeyDatum, serverSaltDatum;
 	gnutls::check(gnutls_srtp_get_keys(mSession, material, materialLen, &clientKeyDatum,
 	                                   &clientSaltDatum, &serverKeyDatum, &serverSaltDatum),
@@ -160,18 +227,23 @@ void DtlsSrtpTransport::postHandshake() {
 	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.
+	PLOG_INFO << "Deriving SRTP keying material (OpenSSL)";
+
+	// The extractor 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");
+
+	// returns 1 on success, 0 or -1 on failure (OpenSSL API is a complete mess...)
+	if (SSL_export_keying_material(mSsl, material, materialLen, label.c_str(), label.size(),
+	                               nullptr, 0, 0) <= 0)
+		throw std::runtime_error("Failed to derive SRTP keys: " +
+		                         openssl::error_string(ERR_get_error()));
 
 	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;
+	serverSalt = serverKey + SRTP_AES_128_KEY_LEN;
 #endif
 
 	unsigned char clientSessionKey[SRTP_AES_ICM_128_KEY_LEN_WSALT];
@@ -182,22 +254,31 @@ void DtlsSrtpTransport::postHandshake() {
 	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 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;
+	inbound.ssrc.value = 0;
+	inbound.key = mIsClient ? serverSessionKey : clientSessionKey;
+	inbound.next = nullptr;
 
-	srtp_policy_t *policies = &inbound;
-	inbound.next = &outbound;
+	if (srtp_err_status_t err = srtp_add_stream(mSrtpIn, &inbound))
+		throw std::runtime_error("SRTP add inbound stream failed, status=" +
+		                         to_string(static_cast<int>(err)));
+
+	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;
+	outbound.ssrc.value = 0;
+	outbound.key = mIsClient ? clientSessionKey : serverSessionKey;
 	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)));
+	if (srtp_err_status_t err = srtp_add_stream(mSrtpOut, &outbound))
+		throw std::runtime_error("SRTP add outbound stream failed, status=" +
+		                         to_string(static_cast<int>(err)));
 
-	mCreated = true;
+	mInitDone = true;
 }
 
 } // namespace rtc

src/dtlssrtptransport.hpp

@@ -38,16 +38,17 @@ public:
 	                  state_callback stateChangeCallback);
 	~DtlsSrtpTransport();
 
-	bool send(message_ptr message) override;
+	bool sendMedia(message_ptr message);
 
 private:
 	void incoming(message_ptr message) override;
+	void postCreation() override;
 	void postHandshake() override;
 
 	message_callback mSrtpRecvCallback;
 
-	srtp_t mSrtp;
-	bool mCreated = false;
+	srtp_t mSrtpIn, mSrtpOut;
+	bool mInitDone = false;
 };
 
 } // namespace rtc

src/dtlstransport.cpp

@@ -85,6 +85,8 @@ DtlsTransport::DtlsTransport(shared_ptr<IceTransport> lower, certificate_ptr cer
 		gnutls_transport_set_pull_function(mSession, ReadCallback);
 		gnutls_transport_set_pull_timeout_function(mSession, TimeoutCallback);
 
+		postCreation();
+
 		mRecvThread = std::thread(&DtlsTransport::runRecvLoop, this);
 		registerIncoming();
 
@@ -137,6 +139,10 @@ void DtlsTransport::incoming(message_ptr message) {
 	mIncomingQueue.push(message);
 }
 
+void DtlsTransport::postCreation() {
+	// Dummy
+}
+
 void DtlsTransport::postHandshake() {
 	// Dummy
 }
@@ -408,6 +414,10 @@ void DtlsTransport::incoming(message_ptr message) {
 	mIncomingQueue.push(message);
 }
 
+void DtlsTransport::postCreation() {
+	// Dummy
+}
+
 void DtlsTransport::postHandshake() {
 	// Dummy
 }

src/dtlstransport.hpp

@@ -52,6 +52,7 @@ public:
 
 protected:
 	virtual void incoming(message_ptr message) override;
+	virtual void postCreation();
 	virtual void postHandshake();
 	void runRecvLoop();
 

src/icetransport.cpp

@@ -42,7 +42,7 @@ using std::shared_ptr;
 using std::weak_ptr;
 using std::chrono::system_clock;
 
-#if USE_JUICE
+#if !USE_NICE
 
 namespace rtc {
 
@@ -269,7 +269,7 @@ void IceTransport::LogCallback(juice_log_level_t level, const char *message) {
 
 } // namespace rtc
 
-#else // USE_JUICE == 0
+#else // USE_NICE == 1
 
 namespace rtc {
 

src/icetransport.hpp

@@ -26,7 +26,7 @@
 #include "peerconnection.hpp"
 #include "transport.hpp"
 
-#if USE_JUICE
+#if !USE_NICE
 #include <juice/juice.h>
 #else
 #include <nice/agent.h>
@@ -63,7 +63,7 @@ public:
 	bool stop() override;
 	bool send(message_ptr message) override; // false if dropped
 
-#if !USE_JUICE
+#if USE_NICE
 	bool getSelectedCandidatePair(CandidateInfo *local, CandidateInfo *remote);
 #endif
 
@@ -85,7 +85,7 @@ private:
 	candidate_callback mCandidateCallback;
 	gathering_state_callback mGatheringStateChangeCallback;
 
-#if USE_JUICE
+#if !USE_NICE
 	std::unique_ptr<juice_agent_t, void (*)(juice_agent_t *)> mAgent;
 	string mStunHostname;
 	string mStunService;

src/init.cpp

@@ -21,6 +21,7 @@
 #include "certificate.hpp"
 #include "dtlstransport.hpp"
 #include "sctptransport.hpp"
+#include "threadpool.hpp"
 #include "tls.hpp"
 
 #if RTC_ENABLE_WEBSOCKET
@@ -39,41 +40,21 @@ using std::shared_ptr;
 
 namespace rtc {
 
-std::weak_ptr<Init> Init::Weak;
-init_token Init::Global;
-std::mutex Init::Mutex;
+namespace {
 
-init_token Init::Token() {
-	std::lock_guard lock(Mutex);
+void doInit() {
+	PLOG_DEBUG << "Global initialization";
 
-	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();
-	CleanupCertificateCache();
-}
-
-Init::Init() {
 #ifdef _WIN32
 	WSADATA wsaData;
 	if (WSAStartup(MAKEWORD(2, 2), &wsaData))
 		throw std::runtime_error("WSAStartup failed, error=" + std::to_string(WSAGetLastError()));
 #endif
 
+	ThreadPool::Instance().spawn(THREADPOOL_SIZE);
+
 #if USE_GNUTLS
-		// Nothing to do
+	// Nothing to do
 #else
 	openssl::init();
 #endif
@@ -88,7 +69,12 @@ Init::Init() {
 #endif
 }
 
-Init::~Init() {
+void doCleanup() {
+	PLOG_DEBUG << "Global cleanup";
+
+	ThreadPool::Instance().join();
+	CleanupCertificateCache();
+
 	SctpTransport::Cleanup();
 	DtlsTransport::Cleanup();
 #if RTC_ENABLE_WEBSOCKET
@@ -103,5 +89,57 @@ Init::~Init() {
 #endif
 }
 
+} // namespace
+
+std::weak_ptr<void> Init::Weak;
+std::shared_ptr<void> *Init::Global = nullptr;
+bool Init::Initialized = false;
+std::recursive_mutex Init::Mutex;
+
+init_token Init::Token() {
+	std::unique_lock lock(Mutex);
+	if (auto token = Weak.lock())
+		return token;
+
+	delete Global;
+	Global = new shared_ptr<void>(new Init());
+	Weak = *Global;
+	return *Global;
+}
+
+void Init::Preload() {
+	std::unique_lock lock(Mutex);
+	auto token = Token();
+	if (!Global)
+		Global = new shared_ptr<void>(token);
+
+	PLOG_DEBUG << "Preloading certificate";
+	make_certificate().wait();
+}
+
+void Init::Cleanup() {
+	std::unique_lock lock(Mutex);
+	delete Global;
+	Global = nullptr;
+}
+
+Init::Init() {
+	// Mutex is locked by Token() here
+	if (!std::exchange(Initialized, true))
+		doInit();
+}
+
+Init::~Init() {
+	std::thread t([]() {
+		// We need to lock Mutex ourselves
+		std::unique_lock lock(Mutex);
+		if (Global)
+			return;
+		if (std::exchange(Initialized, false))
+			doCleanup();
+	});
+	t.detach();
+}
+
 } // namespace rtc
 

src/peerconnection.cpp

@@ -18,9 +18,12 @@
 
 #include "peerconnection.hpp"
 #include "certificate.hpp"
+#include "include.hpp"
+#include "processor.hpp"
+#include "threadpool.hpp"
+
 #include "dtlstransport.hpp"
 #include "icetransport.hpp"
-#include "include.hpp"
 #include "sctptransport.hpp"
 
 #if RTC_ENABLE_MEDIA
@@ -39,8 +42,8 @@ using std::weak_ptr;
 PeerConnection::PeerConnection() : PeerConnection(Configuration()) {}
 
 PeerConnection::PeerConnection(const Configuration &config)
-    : mConfig(config), mCertificate(make_certificate()), mState(State::New),
-      mGatheringState(GatheringState::New) {
+    : mConfig(config), mCertificate(make_certificate()), mProcessor(std::make_unique<Processor>()),
+      mState(State::New), mGatheringState(GatheringState::New) {
 	PLOG_VERBOSE << "Creating PeerConnection";
 
 	if (config.portRangeEnd && config.portRangeBegin > config.portRangeEnd)
@@ -48,13 +51,17 @@ PeerConnection::PeerConnection(const Configuration &config)
 }
 
 PeerConnection::~PeerConnection() {
-	close();
 	PLOG_VERBOSE << "Destroying PeerConnection";
+	close();
+	mProcessor->join();
 }
 
 void PeerConnection::close() {
 	PLOG_VERBOSE << "Closing PeerConnection";
-	closeDataChannels();
+
+	// Close data channels asynchronously
+	mProcessor->enqueue(std::bind(&PeerConnection::closeDataChannels, this));
+
 	closeTransports();
 }
 
@@ -145,6 +152,7 @@ void PeerConnection::addRemoteCandidate(Candidate candidate) {
 		iceTransport->addRemoteCandidate(candidate);
 	} else {
 		// OK, we might need a lookup, do it asynchronously
+		// We don't use the thread pool because we have no control on the timeout
 		weak_ptr<IceTransport> weakIceTransport{iceTransport};
 		std::thread t([weakIceTransport, candidate]() mutable {
 			if (candidate.resolve(Candidate::ResolveMode::Lookup))
@@ -227,7 +235,7 @@ void PeerConnection::sendMedia(const binary &packet) {
 	outgoingMedia(make_message(packet.begin(), packet.end(), Message::Binary));
 }
 
-void PeerConnection::send(const byte *packet, size_t size) {
+void PeerConnection::sendMedia(const byte *packet, size_t size) {
 	outgoingMedia(make_message(packet, packet + size, Message::Binary));
 }
 
@@ -244,7 +252,7 @@ void PeerConnection::outgoingMedia(message_ptr message) {
 	if (!transport)
 		throw std::runtime_error("PeerConnection is not open");
 
-	std::dynamic_pointer_cast<DtlsSrtpTransport>(transport)->send(message);
+	std::dynamic_pointer_cast<DtlsSrtpTransport>(transport)->sendMedia(message);
 #else
 	PLOG_WARNING << "Ignoring sent media (not compiled with SRTP support)";
 #endif
@@ -435,18 +443,19 @@ shared_ptr<SctpTransport> PeerConnection::initSctpTransport() {
 void PeerConnection::closeTransports() {
 	PLOG_VERBOSE << "Closing transports";
 
-	// Change state to sink state Closed to block init methods
+	// Change state to sink state Closed
 	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 {
+	// Initiate transport stop on the processor after closing the data channels
+	mProcessor->enqueue([this]() {
+		// Pass the pointers to a 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));
+		ThreadPool::Instance().enqueue([sctp, dtls, ice]() mutable {
 			if (sctp)
 				sctp->stop();
 			if (dtls)
@@ -458,8 +467,7 @@ void PeerConnection::closeTransports() {
 			dtls.reset();
 			ice.reset();
 		});
-		t.detach();
-	}
+	});
 }
 
 void PeerConnection::endLocalCandidates() {
@@ -502,7 +510,7 @@ void PeerConnection::forwardMessage(message_ptr message) {
 			mDataChannels.insert(std::make_pair(message->stream, channel));
 		} else {
 			// Invalid, close the DataChannel
-			sctpTransport->close(message->stream);
+			sctpTransport->closeStream(message->stream);
 			return;
 		}
 	}
@@ -594,20 +602,26 @@ void PeerConnection::remoteCloseDataChannels() {
 
 void PeerConnection::processLocalDescription(Description description) {
 	std::optional<uint16_t> remoteSctpPort;
-	if (auto remote = remoteDescription())
-		remoteSctpPort = remote->sctpPort();
+	std::optional<string> remoteDataMid;
+	if (auto remote = remoteDescription()) {
+		remoteDataMid = remote->dataMid();
+	    remoteSctpPort = remote->sctpPort();
+	}
 
 	auto certificate = mCertificate.get(); // wait for certificate if not ready
 
 	{
 		std::lock_guard lock(mLocalDescriptionMutex);
 		mLocalDescription.emplace(std::move(description));
+		if (remoteDataMid)
+			mLocalDescription->setDataMid(*remoteDataMid);
+
 		mLocalDescription->setFingerprint(certificate->fingerprint());
 		mLocalDescription->setSctpPort(remoteSctpPort.value_or(DEFAULT_SCTP_PORT));
 		mLocalDescription->setMaxMessageSize(LOCAL_MAX_MESSAGE_SIZE);
 	}
 
-	mLocalDescriptionCallback(*mLocalDescription);
+	mProcessor->enqueue([this]() { mLocalDescriptionCallback(*mLocalDescription); });
 }
 
 void PeerConnection::processLocalCandidate(Candidate candidate) {
@@ -617,7 +631,8 @@ void PeerConnection::processLocalCandidate(Candidate candidate) {
 
 	mLocalDescription->addCandidate(candidate);
 
-	mLocalCandidateCallback(candidate);
+	mProcessor->enqueue(
+	    [this, candidate = std::move(candidate)]() { mLocalCandidateCallback(candidate); });
 }
 
 void PeerConnection::triggerDataChannel(weak_ptr<DataChannel> weakDataChannel) {
@@ -625,7 +640,8 @@ void PeerConnection::triggerDataChannel(weak_ptr<DataChannel> weakDataChannel) {
 	if (!dataChannel)
 		return;
 
-	mDataChannelCallback(dataChannel);
+	mProcessor->enqueue(
+	    [this, dataChannel = std::move(dataChannel)]() { mDataChannelCallback(dataChannel); });
 }
 
 bool PeerConnection::changeState(State state) {
@@ -639,13 +655,18 @@ bool PeerConnection::changeState(State state) {
 
 	} while (!mState.compare_exchange_weak(current, state));
 
-	mStateChangeCallback(state);
+	if (state == State::Closed)
+		// This is the last state change, so we may steal the callback
+		mProcessor->enqueue([this, cb = std::move(mStateChangeCallback)]() { cb(State::Closed); });
+	else
+		mProcessor->enqueue([this, state]() { mStateChangeCallback(state); });
+
 	return true;
 }
 
 bool PeerConnection::changeGatheringState(GatheringState state) {
 	if (mGatheringState.exchange(state) != state)
-		mGatheringStateChangeCallback(state);
+		mProcessor->enqueue([this, state] { mGatheringStateChangeCallback(state); });
 	return true;
 }
 
@@ -660,12 +681,12 @@ void PeerConnection::resetCallbacks() {
 
 bool PeerConnection::getSelectedCandidatePair([[maybe_unused]] CandidateInfo *local,
                                               [[maybe_unused]] CandidateInfo *remote) {
-#if USE_JUICE
-	PLOG_WARNING << "getSelectedCandidatePair() is not implemented for libjuice";
-	return false;
-#else
+#if USE_NICE
 	auto iceTransport = std::atomic_load(&mIceTransport);
 	return iceTransport->getSelectedCandidatePair(local, remote);
+#else
+	PLOG_WARNING << "getSelectedCandidatePair() is only implemented with libnice as ICE backend";
+	return false;
 #endif
 }
 

src/processor.cpp

@@ -0,0 +1,44 @@
+/**
+ * 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 "processor.hpp"
+
+namespace rtc {
+
+Processor::~Processor() { join(); }
+
+void Processor::join() {
+	std::unique_lock lock(mMutex);
+	mCondition.wait(lock, [this]() { return !mPending && mTasks.empty(); });
+}
+
+void Processor::schedule() {
+	std::unique_lock lock(mMutex);
+	if (mTasks.empty()) {
+		// No more tasks
+		mPending = false;
+		mCondition.notify_all();
+		return;
+	}
+
+	ThreadPool::Instance().enqueue(std::move(mTasks.front()));
+	mTasks.pop();
+}
+
+} // namespace rtc
+

src/processor.hpp

@@ -0,0 +1,92 @@
+/**
+ * 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_PROCESSOR_H
+#define RTC_PROCESSOR_H
+
+#include "include.hpp"
+#include "init.hpp"
+#include "threadpool.hpp"
+
+#include <condition_variable>
+#include <future>
+#include <memory>
+#include <mutex>
+#include <queue>
+
+namespace rtc {
+
+// Processed tasks in order by delegating them to the thread pool
+class Processor final {
+public:
+	Processor() = default;
+	~Processor();
+
+	Processor(const Processor &) = delete;
+	Processor &operator=(const Processor &) = delete;
+	Processor(Processor &&) = delete;
+	Processor &operator=(Processor &&) = delete;
+
+	void join();
+
+	template <class F, class... Args>
+	auto enqueue(F &&f, Args &&... args) -> invoke_future_t<F, Args...>;
+
+protected:
+	void schedule();
+
+	// Keep an init token
+	const init_token mInitToken = Init::Token();
+
+	std::queue<std::function<void()>> mTasks;
+	bool mPending = false; // true iff a task is pending in the thread pool
+
+	mutable std::mutex mMutex;
+	std::condition_variable mCondition;
+};
+
+template <class F, class... Args>
+auto Processor::enqueue(F &&f, Args &&... args) -> invoke_future_t<F, Args...> {
+	std::unique_lock lock(mMutex);
+	using R = std::invoke_result_t<std::decay_t<F>, std::decay_t<Args>...>;
+	auto task = std::make_shared<std::packaged_task<R()>>(
+	    std::bind(std::forward<F>(f), std::forward<Args>(args)...));
+	std::future<R> result = task->get_future();
+
+	auto bundle = [this, task = std::move(task)]() {
+		try {
+			(*task)();
+		} catch (const std::exception &e) {
+			PLOG_WARNING << "Unhandled exception in task: " << e.what();
+		}
+		schedule(); // chain the next task
+	};
+
+	if (!mPending) {
+		ThreadPool::Instance().enqueue(std::move(bundle));
+		mPending = true;
+	} else {
+		mTasks.emplace(std::move(bundle));
+	}
+
+	return result;
+}
+
+} // namespace rtc
+
+#endif

src/rtc.cpp

@@ -55,18 +55,15 @@ std::unordered_map<int, void *> userPointerMap;
 std::mutex mutex;
 int lastId = 0;
 
-void *getUserPointer(int id) {
+std::optional<void *> getUserPointer(int id) {
 	std::lock_guard lock(mutex);
 	auto it = userPointerMap.find(id);
-	return it != userPointerMap.end() ? it->second : nullptr;
+	return it != userPointerMap.end() ? std::make_optional(it->second) : nullopt;
 }
 
 void setUserPointer(int i, void *ptr) {
 	std::lock_guard lock(mutex);
-	if (ptr)
-		userPointerMap[i] = ptr;
-	else
-		userPointerMap.erase(i);
+	userPointerMap[i] = ptr;
 }
 
 shared_ptr<PeerConnection> getPeerConnection(int id) {
@@ -89,6 +86,7 @@ int emplacePeerConnection(shared_ptr<PeerConnection> ptr) {
 	std::lock_guard lock(mutex);
 	int pc = ++lastId;
 	peerConnectionMap.emplace(std::make_pair(pc, ptr));
+	userPointerMap.emplace(std::make_pair(pc, nullptr));
 	return pc;
 }
 
@@ -96,6 +94,7 @@ int emplaceDataChannel(shared_ptr<DataChannel> ptr) {
 	std::lock_guard lock(mutex);
 	int dc = ++lastId;
 	dataChannelMap.emplace(std::make_pair(dc, ptr));
+	userPointerMap.emplace(std::make_pair(dc, nullptr));
 	return dc;
 }
 
@@ -126,6 +125,7 @@ int emplaceWebSocket(shared_ptr<WebSocket> ptr) {
 	std::lock_guard lock(mutex);
 	int ws = ++lastId;
 	webSocketMap.emplace(std::make_pair(ws, ptr));
+	userPointerMap.emplace(std::make_pair(ws, nullptr));
 	return ws;
 }
 
@@ -244,7 +244,8 @@ int rtcCreateDataChannel(int pc, const char *label) {
 	return WRAP({
 		auto peerConnection = getPeerConnection(pc);
 		int dc = emplaceDataChannel(peerConnection->createDataChannel(string(label)));
-		rtcSetUserPointer(dc, getUserPointer(pc));
+		if (auto ptr = getUserPointer(pc))
+			rtcSetUserPointer(dc, *ptr);
 		return dc;
 	});
 }
@@ -272,6 +273,16 @@ int rtcCreateWebSocket(const char *url) {
 	});
 }
 
+int rtcCreateWebSocketEx(const char *url, const rtcWsConfiguration *config) {
+	return WRAP({
+		WebSocket::Configuration c;
+		c.disableTlsVerification = config->disableTlsVerification;
+		auto ws = std::make_shared<WebSocket>(c);
+		ws->open(url);
+		return emplaceWebSocket(ws);
+	});
+}
+
 int rtcDeleteWebsocket(int ws) {
 	return WRAP({
 		auto webSocket = getWebSocket(ws);
@@ -293,9 +304,10 @@ int rtcSetDataChannelCallback(int pc, rtcDataChannelCallbackFunc cb) {
 		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);
+				if (auto ptr = getUserPointer(pc)) {
+					rtcSetUserPointer(dc, *ptr);
+					cb(dc, *ptr);
+				}
 			});
 		else
 			peerConnection->onDataChannel(nullptr);
@@ -307,7 +319,8 @@ int rtcSetLocalDescriptionCallback(int pc, rtcDescriptionCallbackFunc cb) {
 		auto peerConnection = getPeerConnection(pc);
 		if (cb)
 			peerConnection->onLocalDescription([pc, cb](const Description &desc) {
-				cb(string(desc).c_str(), desc.typeString().c_str(), getUserPointer(pc));
+				if (auto ptr = getUserPointer(pc))
+					cb(string(desc).c_str(), desc.typeString().c_str(), *ptr);
 			});
 		else
 			peerConnection->onLocalDescription(nullptr);
@@ -319,7 +332,8 @@ int rtcSetLocalCandidateCallback(int pc, rtcCandidateCallbackFunc cb) {
 		auto peerConnection = getPeerConnection(pc);
 		if (cb)
 			peerConnection->onLocalCandidate([pc, cb](const Candidate &cand) {
-				cb(cand.candidate().c_str(), cand.mid().c_str(), getUserPointer(pc));
+				if (auto ptr = getUserPointer(pc))
+					cb(cand.candidate().c_str(), cand.mid().c_str(), *ptr);
 			});
 		else
 			peerConnection->onLocalCandidate(nullptr);
@@ -331,7 +345,8 @@ int rtcSetStateChangeCallback(int pc, rtcStateChangeCallbackFunc cb) {
 		auto peerConnection = getPeerConnection(pc);
 		if (cb)
 			peerConnection->onStateChange([pc, cb](PeerConnection::State state) {
-				cb(static_cast<rtcState>(state), getUserPointer(pc));
+				if (auto ptr = getUserPointer(pc))
+					cb(static_cast<rtcState>(state), *ptr);
 			});
 		else
 			peerConnection->onStateChange(nullptr);
@@ -343,7 +358,8 @@ int rtcSetGatheringStateChangeCallback(int pc, rtcGatheringStateCallbackFunc cb)
 		auto peerConnection = getPeerConnection(pc);
 		if (cb)
 			peerConnection->onGatheringStateChange([pc, cb](PeerConnection::GatheringState state) {
-				cb(static_cast<rtcGatheringState>(state), getUserPointer(pc));
+				if (auto ptr = getUserPointer(pc))
+					cb(static_cast<rtcGatheringState>(state), *ptr);
 			});
 		else
 			peerConnection->onGatheringStateChange(nullptr);
@@ -435,7 +451,10 @@ int rtcSetOpenCallback(int id, rtcOpenCallbackFunc cb) {
 	return WRAP({
 		auto channel = getChannel(id);
 		if (cb)
-			channel->onOpen([id, cb]() { cb(getUserPointer(id)); });
+			channel->onOpen([id, cb]() {
+				if (auto ptr = getUserPointer(id))
+					cb(*ptr);
+			});
 		else
 			channel->onOpen(nullptr);
 	});
@@ -445,7 +464,10 @@ int rtcSetClosedCallback(int id, rtcClosedCallbackFunc cb) {
 	return WRAP({
 		auto channel = getChannel(id);
 		if (cb)
-			channel->onClosed([id, cb]() { cb(getUserPointer(id)); });
+			channel->onClosed([id, cb]() {
+				if (auto ptr = getUserPointer(id))
+					cb(*ptr);
+			});
 		else
 			channel->onClosed(nullptr);
 	});
@@ -455,8 +477,10 @@ int rtcSetErrorCallback(int id, rtcErrorCallbackFunc cb) {
 	return WRAP({
 		auto channel = getChannel(id);
 		if (cb)
-			channel->onError(
-			    [id, cb](const string &error) { cb(error.c_str(), getUserPointer(id)); });
+			channel->onError([id, cb](const string &error) {
+				if (auto ptr = getUserPointer(id))
+					cb(error.c_str(), *ptr);
+			});
 		else
 			channel->onError(nullptr);
 	});
@@ -468,9 +492,13 @@ int rtcSetMessageCallback(int id, rtcMessageCallbackFunc cb) {
 		if (cb)
 			channel->onMessage(
 			    [id, cb](const binary &b) {
-				    cb(reinterpret_cast<const char *>(b.data()), int(b.size()), getUserPointer(id));
+				    if (auto ptr = getUserPointer(id))
+					    cb(reinterpret_cast<const char *>(b.data()), int(b.size()), *ptr);
 			    },
-			    [id, cb](const string &s) { cb(s.c_str(), -1, getUserPointer(id)); });
+			    [id, cb](const string &s) {
+				    if (auto ptr = getUserPointer(id))
+					    cb(s.c_str(), -int(s.size() + 1), *ptr);
+			    });
 		else
 			channel->onMessage(nullptr);
 	});
@@ -514,7 +542,10 @@ int rtcSetBufferedAmountLowCallback(int id, rtcBufferedAmountLowCallbackFunc cb)
 	return WRAP({
 		auto channel = getChannel(id);
 		if (cb)
-			channel->onBufferedAmountLow([id, cb]() { cb(getUserPointer(id)); });
+			channel->onBufferedAmountLow([id, cb]() {
+				if (auto ptr = getUserPointer(id))
+					cb(*ptr);
+			});
 		else
 			channel->onBufferedAmountLow(nullptr);
 	});
@@ -528,7 +559,10 @@ int rtcSetAvailableCallback(int id, rtcAvailableCallbackFunc cb) {
 	return WRAP({
 		auto channel = getChannel(id);
 		if (cb)
-			channel->onOpen([id, cb]() { cb(getUserPointer(id)); });
+			channel->onOpen([id, cb]() {
+				if (auto ptr = getUserPointer(id))
+					cb(*ptr);
+			});
 		else
 			channel->onOpen(nullptr);
 	});

src/sctptransport.cpp

@@ -24,7 +24,7 @@
 #include <thread>
 #include <vector>
 
-#ifdef USE_JUICE
+#if !USE_NICE
 #ifndef __APPLE__
 // libjuice enables Linux path MTU discovery or sets the DF flag
 #define USE_PMTUD 1
@@ -32,7 +32,7 @@
 // Setting the DF flag is not available on Mac OS
 #define USE_PMTUD 0
 #endif
-#else
+#else // USE_NICE == 1
 #ifdef __linux__
 // Linux UDP does path MTU discovery by default (setting DF and returning EMSGSIZE)
 // It should be safe to enable discovery for SCTP.
@@ -50,6 +50,9 @@ using std::shared_ptr;
 
 namespace rtc {
 
+std::unordered_set<SctpTransport *> SctpTransport::Instances;
+std::shared_mutex SctpTransport::InstancesMutex;
+
 void SctpTransport::Init() {
 	usrsctp_init(0, &SctpTransport::WriteCallback, nullptr);
 	usrsctp_sysctl_set_sctp_ecn_enable(0);
@@ -92,6 +95,11 @@ SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port,
 	PLOG_DEBUG << "Initializing SCTP transport";
 
 	usrsctp_register_address(this);
+	{
+		std::unique_lock lock(InstancesMutex);
+		Instances.insert(this);
+	}
+
 	mSock = usrsctp_socket(AF_CONN, SOCK_STREAM, IPPROTO_SCTP, &SctpTransport::RecvCallback,
 	                       &SctpTransport::SendCallback, 0, this);
 	if (!mSock)
@@ -186,14 +194,21 @@ SctpTransport::SctpTransport(std::shared_ptr<Transport> lower, uint16_t port,
 
 SctpTransport::~SctpTransport() {
 	stop();
-
-	if (mSock)
-		usrsctp_close(mSock);
+	close();
 
 	usrsctp_deregister_address(this);
+	{
+		std::unique_lock lock(InstancesMutex);
+		Instances.erase(this);
+	}
 }
 
 bool SctpTransport::stop() {
+	// Transport::stop() will unregister incoming() from the lower layer, therefore we need to make
+	// sure the thread from lower layers is not blocked in incoming() by the WrittenOnce condition.
+	mWrittenOnce = true;
+	mWrittenCondition.notify_all();
+
 	if (!Transport::stop())
 		return false;
 
@@ -204,6 +219,13 @@ bool SctpTransport::stop() {
 	return true;
 }
 
+void SctpTransport::close() {
+	if (mSock) {
+		usrsctp_close(mSock);
+		mSock = nullptr;
+	}
+}
+
 void SctpTransport::connect() {
 	if (!mSock)
 		return;
@@ -240,9 +262,7 @@ void SctpTransport::shutdown() {
 		PLOG_WARNING << "SCTP shutdown failed, errno=" << errno;
 	}
 
-	// close() abort the connection when linger is disabled, call it now
-	usrsctp_close(mSock);
-	mSock = nullptr;
+	close();
 
 	PLOG_INFO << "SCTP disconnected";
 	changeState(State::Disconnected);
@@ -266,7 +286,7 @@ bool SctpTransport::send(message_ptr message) {
 	return false;
 }
 
-void SctpTransport::close(unsigned int stream) {
+void SctpTransport::closeStream(unsigned int stream) {
 	send(make_message(0, Message::Reset, uint16_t(stream)));
 }
 
@@ -405,7 +425,7 @@ void SctpTransport::updateBufferedAmount(uint16_t streamId, long delta) {
 	try {
 		mBufferedAmountCallback(streamId, amount);
 	} catch (const std::exception &e) {
-		PLOG_WARNING << "SCTP buffered amount callback: " << e.what();
+		PLOG_DEBUG << "SCTP buffered amount callback: " << e.what();
 	}
 	mSendMutex.lock();
 }
@@ -431,7 +451,7 @@ void SctpTransport::sendReset(uint16_t streamId) {
 		mWrittenCondition.wait_for(lock, 1000ms,
 		                           [&]() { return mWritten || state() != State::Connected; });
 	} else if (errno == EINVAL) {
-		PLOG_VERBOSE << "SCTP stream " << streamId << " already reset";
+		PLOG_DEBUG << "SCTP stream " << streamId << " already reset";
 	} else {
 		PLOG_WARNING << "SCTP reset stream " << streamId << " failed, errno=" << errno;
 	}
@@ -459,32 +479,22 @@ int SctpTransport::handleRecv(struct socket * /*sock*/, union sctp_sockstore /*a
 		// therefore partial notifications and messages need to be handled separately.
 		if (flags & MSG_NOTIFICATION) {
 			// SCTP event notification
+			mPartialNotification.insert(mPartialNotification.end(), data, data + len);
 			if (flags & MSG_EOR) {
-				if (!mPartialNotification.empty()) {
-					mPartialNotification.insert(mPartialNotification.end(), data, data + len);
-					data = mPartialNotification.data();
-					len = mPartialNotification.size();
-				}
 				// Notification is complete, process it
-				processNotification(reinterpret_cast<const union sctp_notification *>(data), len);
+				processNotification(
+				    reinterpret_cast<const union sctp_notification *>(mPartialNotification.data()),
+				    mPartialNotification.size());
 				mPartialNotification.clear();
-			} else {
-				mPartialNotification.insert(mPartialNotification.end(), data, data + len);
 			}
-
 		} else {
 			// SCTP message
+			mPartialMessage.insert(mPartialMessage.end(), data, data + len);
 			if (flags & MSG_EOR) {
-				if (!mPartialMessage.empty()) {
-					mPartialMessage.insert(mPartialMessage.end(), data, data + len);
-					data = mPartialMessage.data();
-					len = mPartialMessage.size();
-				}
 				// Message is complete, process it
-				processData(data, len, info.rcv_sid, PayloadId(htonl(info.rcv_ppid)));
+				processData(std::move(mPartialMessage), info.rcv_sid,
+				            PayloadId(htonl(info.rcv_ppid)));
 				mPartialMessage.clear();
-			} else {
-				mPartialMessage.insert(mPartialMessage.end(), data, data + len);
 			}
 		}
 
@@ -502,9 +512,9 @@ int SctpTransport::handleSend(size_t free) {
 
 int SctpTransport::handleWrite(byte *data, size_t len, uint8_t /*tos*/, uint8_t /*set_df*/) {
 	try {
+		std::unique_lock lock(mWriteMutex);
 		PLOG_VERBOSE << "Handle write, len=" << len;
 
-		std::unique_lock lock(mWriteMutex);
 		if (!outgoing(make_message(data, data + len)))
 			return -1;
 
@@ -519,62 +529,56 @@ int SctpTransport::handleWrite(byte *data, size_t len, uint8_t /*tos*/, uint8_t
 	return 0; // success
 }
 
-void SctpTransport::processData(const byte *data, size_t len, uint16_t sid, PayloadId ppid) {
-	PLOG_VERBOSE << "Process data, len=" << len;
+void SctpTransport::processData(binary &&data, uint16_t sid, PayloadId ppid) {
+	PLOG_VERBOSE << "Process data, size=" << data.size();
 
 	// 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_CONTROL:
-		recv(make_message(data, data + len, Message::Control, sid));
+		recv(make_message(std::move(data), Message::Control, sid));
 		break;
 
 	case PPID_STRING_PARTIAL: // deprecated
-		mPartialStringData.insert(mPartialStringData.end(), data, data + len);
+		mPartialStringData.insert(mPartialStringData.end(), data.begin(), data.end());
 		break;
 
 	case PPID_STRING:
 		if (mPartialStringData.empty()) {
-			mBytesReceived += len;
-			recv(make_message(data, data + len, Message::String, sid));
+			mBytesReceived += data.size();
+			recv(make_message(std::move(data), Message::String, sid));
 		} else {
-			mPartialStringData.insert(mPartialStringData.end(), data, data + len);
+			mPartialStringData.insert(mPartialStringData.end(), data.begin(), data.end());
 			mBytesReceived += mPartialStringData.size();
-			recv(make_message(mPartialStringData.begin(), mPartialStringData.end(), Message::String,
-			                  sid));
+			recv(make_message(std::move(mPartialStringData), 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));
+		recv(make_message(std::move(mPartialStringData), Message::String, sid));
 		mPartialStringData.clear();
 		break;
 
 	case PPID_BINARY_PARTIAL: // deprecated
-		mPartialBinaryData.insert(mPartialBinaryData.end(), data, data + len);
+		mPartialBinaryData.insert(mPartialBinaryData.end(), data.begin(), data.end());
 		break;
 
 	case PPID_BINARY:
 		if (mPartialBinaryData.empty()) {
-			mBytesReceived += len;
-			recv(make_message(data, data + len, Message::Binary, sid));
+			mBytesReceived += data.size();
+			recv(make_message(std::move(data), 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.insert(mPartialBinaryData.end(), data.begin(), data.end());
+			mBytesReceived += mPartialBinaryData.size();
+			recv(make_message(std::move(mPartialBinaryData), 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));
+		recv(make_message(std::move(mPartialBinaryData), Message::Binary, sid));
 		mPartialBinaryData.clear();
 		break;
 
@@ -628,7 +632,7 @@ void SctpTransport::processNotification(const union sctp_notification *notify, s
 		if (flags & SCTP_STREAM_RESET_OUTGOING_SSN) {
 			for (int i = 0; i < count; ++i) {
 				uint16_t streamId = reset_event.strreset_stream_list[i];
-				close(streamId);
+				closeStream(streamId);
 			}
 		}
 		if (flags & SCTP_STREAM_RESET_INCOMING_SSN) {
@@ -686,7 +690,15 @@ int SctpTransport::SendCallback(struct socket *sock, uint32_t sb_free) {
 
 	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));
+	auto *transport = static_cast<SctpTransport *>(ptr);
+
+	// Workaround for sctplab/usrsctp#405: Send callback is invoked on already closed socket
+	// https://github.com/sctplab/usrsctp/issues/405
+	std::shared_lock lock(InstancesMutex);
+	if (Instances.find(transport) == Instances.end())
+		return -1;
+
+	return transport->handleSend(size_t(sb_free));
 }
 
 int SctpTransport::WriteCallback(void *ptr, void *data, size_t len, uint8_t tos, uint8_t set_df) {

src/sctptransport.hpp

@@ -28,6 +28,8 @@
 #include <functional>
 #include <map>
 #include <mutex>
+#include <shared_mutex>
+#include <unordered_set>
 
 #include "usrsctp.h"
 
@@ -46,7 +48,7 @@ public:
 
 	bool stop() override;
 	bool send(message_ptr message) override; // false if buffered
-	void close(unsigned int stream);
+	void closeStream(unsigned int stream);
 	void flush();
 
 	// Stats
@@ -70,6 +72,7 @@ private:
 
 	void connect();
 	void shutdown();
+	void close();
 	void incoming(message_ptr message) override;
 
 	bool trySendQueue();
@@ -83,7 +86,7 @@ private:
 	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 processData(binary &&data, uint16_t streamId, PayloadId ppid);
 	void processNotification(const union sctp_notification *notify, size_t len);
 
 	const uint16_t mPort;
@@ -109,6 +112,9 @@ private:
 	                        struct sctp_rcvinfo recv_info, int flags, void *user_data);
 	static int SendCallback(struct socket *sock, uint32_t sb_free);
 	static int WriteCallback(void *sctp_ptr, void *data, size_t len, uint8_t tos, uint8_t set_df);
+
+	static std::unordered_set<SctpTransport *> Instances;
+	static std::shared_mutex InstancesMutex;
 };
 
 } // namespace rtc

src/tcptransport.cpp

@@ -38,8 +38,8 @@ SelectInterrupter::SelectInterrupter() {
 		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
+	mPipeOut = pipefd[1]; // read
+	mPipeIn = pipefd[0];  // write
 #endif
 }
 
@@ -62,11 +62,8 @@ int SelectInterrupter::prepare(fd_set &readfds, fd_set &writefds) {
 	FD_SET(mDummySock, &readfds);
 	return SOCKET_TO_INT(mDummySock) + 1;
 #else
-	int ret;
-	do {
-		char dummy;
-		ret = ::read(mPipeIn, &dummy, 1);
-	} while (ret > 0);
+	char dummy;
+	::read(mPipeIn, &dummy, 1);
 	FD_SET(mPipeIn, &readfds);
 	return mPipeIn + 1;
 #endif
@@ -107,6 +104,7 @@ bool TcpTransport::stop() {
 }
 
 bool TcpTransport::send(message_ptr message) {
+	std::unique_lock lock(mSockMutex);
 	if (state() != State::Connected)
 		return false;
 
@@ -126,6 +124,7 @@ void TcpTransport::incoming(message_ptr message) {
 }
 
 bool TcpTransport::outgoing(message_ptr message) {
+	// mSockMutex must be locked
 	// 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))
@@ -174,6 +173,7 @@ void TcpTransport::connect(const string &hostname, const string &service) {
 }
 
 void TcpTransport::connect(const sockaddr *addr, socklen_t addrlen) {
+	std::unique_lock lock(mSockMutex);
 	try {
 		char node[MAX_NUMERICNODE_LEN];
 		char serv[MAX_NUMERICSERV_LEN];
@@ -248,15 +248,18 @@ void TcpTransport::connect(const sockaddr *addr, socklen_t addrlen) {
 }
 
 void TcpTransport::close() {
+	std::unique_lock lock(mSockMutex);
 	if (mSock != INVALID_SOCKET) {
 		PLOG_DEBUG << "Closing TCP socket";
 		::closesocket(mSock);
 		mSock = INVALID_SOCKET;
 	}
 	changeState(State::Disconnected);
+	interruptSelect();
 }
 
 bool TcpTransport::trySendQueue() {
+	// mSockMutex must be locked
 	while (auto next = mSendQueue.peek()) {
 		auto message = *next;
 		if (!trySendMessage(message)) {
@@ -269,6 +272,7 @@ bool TcpTransport::trySendQueue() {
 }
 
 bool TcpTransport::trySendMessage(message_ptr &message) {
+	// mSockMutex must be locked
 	auto data = reinterpret_cast<const char *>(message->data());
 	auto size = message->size();
 	while (size) {
@@ -314,17 +318,27 @@ void TcpTransport::runLoop() {
 		changeState(State::Connected);
 
 		while (true) {
+			std::unique_lock lock(mSockMutex);
+			if (mSock == INVALID_SOCKET)
+				break;
+
 			fd_set readfds, writefds;
 			int n = prepareSelect(readfds, writefds);
 
 			struct timeval tv;
 			tv.tv_sec = 10;
 			tv.tv_usec = 0;
+			lock.unlock();
 			int ret = ::select(n, &readfds, &writefds, NULL, &tv);
+			lock.lock();
+			if (mSock == INVALID_SOCKET)
+				break;
+
 			if (ret < 0) {
 				throw std::runtime_error("Failed to wait on socket");
 			} else if (ret == 0) {
 				PLOG_VERBOSE << "TCP is idle";
+				lock.unlock(); // unlock now since the upper layer might send on incoming
 				incoming(make_message(0));
 				continue;
 			}
@@ -346,6 +360,7 @@ void TcpTransport::runLoop() {
 				if (len == 0)
 					break; // clean close
 
+				lock.unlock(); // unlock now since the upper layer might send on incoming
 				auto *b = reinterpret_cast<byte *>(buffer);
 				incoming(make_message(b, b + len));
 			}

src/tcptransport.hpp

@@ -78,6 +78,7 @@ private:
 	string mHostname, mService;
 
 	socket_t mSock = INVALID_SOCKET;
+	std::mutex mSockMutex;
 	std::thread mThread;
 	SelectInterrupter mInterrupter;
 	Queue<message_ptr> mSendQueue;

src/threadpool.cpp

@@ -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
+ */
+
+#include "threadpool.hpp"
+
+namespace rtc {
+
+ThreadPool &ThreadPool::Instance() {
+	// Init handles joining on cleanup
+	static ThreadPool *instance = new ThreadPool;
+	return *instance;
+}
+
+ThreadPool::~ThreadPool() { join(); }
+
+int ThreadPool::count() const {
+	std::unique_lock lock(mWorkersMutex);
+	return int(mWorkers.size());
+}
+
+void ThreadPool::spawn(int count) {
+	std::unique_lock lock(mWorkersMutex);
+	mJoining = false;
+	while (count-- > 0)
+		mWorkers.emplace_back(std::bind(&ThreadPool::run, this));
+}
+
+void ThreadPool::join() {
+	std::unique_lock lock(mWorkersMutex);
+	mJoining = true;
+	mCondition.notify_all();
+
+	for (auto &w : mWorkers)
+		w.join();
+
+	mWorkers.clear();
+}
+
+void ThreadPool::run() {
+	while (runOne()) {
+	}
+}
+
+bool ThreadPool::runOne() {
+	if (auto task = dequeue()) {
+		try {
+			task();
+		} catch (const std::exception &e) {
+			PLOG_WARNING << "Unhandled exception in task: " << e.what();
+		}
+		return true;
+	}
+	return false;
+}
+
+std::function<void()> ThreadPool::dequeue() {
+	std::unique_lock lock(mMutex);
+	mCondition.wait(lock, [this]() { return !mTasks.empty() || mJoining; });
+	if (mTasks.empty())
+		return nullptr;
+	auto task = std::move(mTasks.front());
+	mTasks.pop();
+	return task;
+}
+
+} // namespace rtc
+

src/threadpool.hpp

@@ -0,0 +1,87 @@
+/**
+ * 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_THREADPOOL_H
+#define RTC_THREADPOOL_H
+
+#include "include.hpp"
+#include "init.hpp"
+
+#include <condition_variable>
+#include <functional>
+#include <future>
+#include <memory>
+#include <mutex>
+#include <queue>
+#include <stdexcept>
+#include <thread>
+#include <vector>
+
+namespace rtc {
+
+template <class F, class... Args>
+using invoke_future_t = std::future<std::invoke_result_t<std::decay_t<F>, std::decay_t<Args>...>>;
+
+class ThreadPool final {
+public:
+	static ThreadPool &Instance();
+
+	ThreadPool(const ThreadPool &) = delete;
+	ThreadPool &operator=(const ThreadPool &) = delete;
+	ThreadPool(ThreadPool &&) = delete;
+	ThreadPool &operator=(ThreadPool &&) = delete;
+
+	int count() const;
+	void spawn(int count = 1);
+	void join();
+	void run();
+	bool runOne();
+
+	template <class F, class... Args>
+	auto enqueue(F &&f, Args &&... args) -> invoke_future_t<F, Args...>;
+
+protected:
+	ThreadPool() = default;
+	~ThreadPool();
+
+	std::function<void()> dequeue(); // returns null function if joining
+
+	std::vector<std::thread> mWorkers;
+	std::queue<std::function<void()>> mTasks;
+	std::atomic<bool> mJoining = false;
+
+	mutable std::mutex mMutex, mWorkersMutex;
+	std::condition_variable mCondition;
+};
+
+template <class F, class... Args>
+auto ThreadPool::enqueue(F &&f, Args &&... args) -> invoke_future_t<F, Args...> {
+	std::unique_lock lock(mMutex);
+	using R = std::invoke_result_t<std::decay_t<F>, std::decay_t<Args>...>;
+	auto task = std::make_shared<std::packaged_task<R()>>(
+	    std::bind(std::forward<F>(f), std::forward<Args>(args)...));
+	std::future<R> result = task->get_future();
+
+	mTasks.emplace([task = std::move(task), token = Init::Token()]() { return (*task)(); });
+	mCondition.notify_one();
+	return result;
+}
+
+} // namespace rtc
+
+#endif

src/tls.cpp

@@ -86,9 +86,8 @@ void init() {
 
 	std::lock_guard lock(mutex);
 	if (!done) {
-		OPENSSL_init_ssl(0, NULL);
-		SSL_load_error_strings();
-		ERR_load_crypto_strings();
+		OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS | OPENSSL_INIT_LOAD_CRYPTO_STRINGS, nullptr);
+		OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CRYPTO_STRINGS, nullptr);
 		done = true;
 	}
 }

src/tls.hpp

@@ -60,6 +60,8 @@ gnutls_datum_t make_datum(char *data, size_t size);
 #include <openssl/err.h>
 #include <openssl/pem.h>
 #include <openssl/x509.h>
+#include <openssl/rsa.h>
+#include <openssl/bn.h>
 
 #ifndef BIO_EOF
 #define BIO_EOF -1

src/tlstransport.cpp

@@ -56,7 +56,6 @@ TlsTransport::TlsTransport(shared_ptr<TcpTransport> lower, string host, state_ca
 	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;
@@ -72,7 +71,9 @@ TlsTransport::TlsTransport(shared_ptr<TcpTransport> lower, string host, state_ca
 		gnutls_transport_set_pull_function(mSession, ReadCallback);
 		gnutls_transport_set_pull_timeout_function(mSession, TimeoutCallback);
 
-       	mRecvThread = std::thread(&TlsTransport::runRecvLoop, this);
+		postCreation();
+
+		mRecvThread = std::thread(&TlsTransport::runRecvLoop, this);
 		registerIncoming();
 
 	} catch (...) {
@@ -123,6 +124,14 @@ void TlsTransport::incoming(message_ptr message) {
 		mIncomingQueue.stop();
 }
 
+void TlsTransport::postCreation() {
+	// Dummy
+}
+
+void TlsTransport::postHandshake() {
+	// Dummy
+}
+
 void TlsTransport::runRecvLoop() {
 	const size_t bufferSize = 4096;
 	char buffer[bufferSize];
@@ -147,6 +156,7 @@ void TlsTransport::runRecvLoop() {
 	try {
 		PLOG_INFO << "TLS handshake finished";
 		changeState(State::Connected);
+		postHandshake();
 
 		while (true) {
 			ssize_t ret;
@@ -263,25 +273,16 @@ TlsTransport::TlsTransport(shared_ptr<TcpTransport> lower, string host, state_ca
 		openssl::check(SSL_CTX_set_cipher_list(mCtx, "ALL:!LOW:!EXP:!RC4:!MD5:@STRENGTH"),
 		               "Failed to set SSL priorities");
 
+		if (!SSL_CTX_set_default_verify_paths(mCtx)) {
+			PLOG_WARNING << "SSL root CA certificates unavailable";
+		}
+
 		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() does nothing on Windows
-#ifndef _WIN32
-		if (SSL_CTX_set_default_verify_paths(mCtx)) {
-#else
-		if (false) {
-#endif
-			PLOG_INFO << "SSL root CA certificates available, server verification enabled";
-			SSL_CTX_set_verify(mCtx, SSL_VERIFY_PEER, NULL);
-			SSL_CTX_set_verify_depth(mCtx, 4);
-		} else {
-			PLOG_WARNING << "SSL root CA certificates unavailable, server verification disabled";
-			SSL_CTX_set_verify(mCtx, SSL_VERIFY_NONE, NULL);
-		}
+		SSL_CTX_set_verify(mCtx, SSL_VERIFY_NONE, NULL);
 
 		if (!(mSsl = SSL_new(mCtx)))
 			throw std::runtime_error("Failed to create SSL instance");
@@ -308,6 +309,8 @@ TlsTransport::TlsTransport(shared_ptr<TcpTransport> lower, string host, state_ca
 		SSL_set_options(mSsl, SSL_OP_SINGLE_ECDH_USE);
 		SSL_set_tmp_ecdh(mSsl, ecdh.get());
 
+		postCreation();
+
 		mRecvThread = std::thread(&TlsTransport::runRecvLoop, this);
 		registerIncoming();
 
@@ -366,6 +369,14 @@ void TlsTransport::incoming(message_ptr message) {
 		mIncomingQueue.stop();
 }
 
+void TlsTransport::postCreation() {
+	// Dummy
+}
+
+void TlsTransport::postHandshake() {
+	// Dummy
+}
+
 void TlsTransport::runRecvLoop() {
 	const size_t bufferSize = 4096;
 	byte buffer[bufferSize];
@@ -387,6 +398,7 @@ void TlsTransport::runRecvLoop() {
 				if (SSL_is_init_finished(mSsl)) {
 					PLOG_INFO << "TLS handshake finished";
 					changeState(State::Connected);
+					postHandshake();
 				}
 			} else {
 				int ret = SSL_read(mSsl, buffer, bufferSize);

src/tlstransport.hpp

@@ -38,14 +38,15 @@ public:
 	static void Cleanup();
 
 	TlsTransport(std::shared_ptr<TcpTransport> lower, string host, state_callback callback);
-	~TlsTransport();
+	virtual ~TlsTransport();
 
 	bool stop() override;
 	bool send(message_ptr message) override;
 
-	void incoming(message_ptr message) override;
-
 protected:
+	virtual void incoming(message_ptr message) override;
+	virtual void postCreation();
+	virtual void postHandshake();
 	void runRecvLoop();
 
 	string mHost;

src/transport.hpp

@@ -41,12 +41,17 @@ public:
 
 	virtual ~Transport() {
 		stop();
-		if (mLower)
-			mLower->onRecv(nullptr); // doing it on stop could cause a deadlock
 	}
 
 	virtual bool stop() {
-		return !mShutdown.exchange(true);
+		if (mShutdown.exchange(true))
+			return false;
+
+		// We don't want incoming() to be called by the lower layer anymore
+		if (mLower)
+			mLower->onRecv(nullptr);
+
+		return true;
 	}
 
 	void registerIncoming() {
@@ -60,10 +65,20 @@ public:
 	virtual bool send(message_ptr message) { return outgoing(message); }
 
 protected:
-	void recv(message_ptr message) { mRecvCallback(message); }
+	void recv(message_ptr message) {
+		try {
+			mRecvCallback(message);
+		} catch (const std::exception &e) {
+			PLOG_WARNING << e.what();
+		}
+	}
 	void changeState(State state) {
-		if (mState.exchange(state) != state)
-			mStateChangeCallback(state);
+		try {
+			if (mState.exchange(state) != state)
+				mStateChangeCallback(state);
+		} catch (const std::exception &e) {
+			PLOG_WARNING << e.what();
+		}
 	}
 
 	virtual void incoming(message_ptr message) { recv(message); }

src/verifiedtlstransport.cpp

@@ -0,0 +1,70 @@
+/**
+ * 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 "verifiedtlstransport.hpp"
+#include "include.hpp"
+
+#if RTC_ENABLE_WEBSOCKET
+
+using std::shared_ptr;
+using std::string;
+using std::unique_ptr;
+using std::weak_ptr;
+
+namespace rtc {
+
+#if USE_GNUTLS
+
+VerifiedTlsTransport::VerifiedTlsTransport(shared_ptr<TcpTransport> lower, string host,
+                                           state_callback callback)
+    : TlsTransport(std::move(lower), std::move(host), std::move(callback)) {}
+
+VerifiedTlsTransport::~VerifiedTlsTransport() {}
+
+void VerifiedTlsTransport::postCreation() {
+	PLOG_DEBUG << "Setting up TLS certificate verification";
+	gnutls_session_set_verify_cert(mSession, mHost.c_str(), 0);
+}
+
+void VerifiedTlsTransport::postHandshake() {
+	// Nothing to do
+}
+
+#else // USE_GNUTLS==0
+
+VerifiedTlsTransport::VerifiedTlsTransport(shared_ptr<TcpTransport> lower, string host,
+                                           state_callback callback)
+    : TlsTransport(std::move(lower), std::move(host), std::move(callback)) {}
+
+VerifiedTlsTransport::~VerifiedTlsTransport() {}
+
+void VerifiedTlsTransport::postCreation() {
+	PLOG_DEBUG << "Setting up TLS certificate verification";
+	SSL_set_verify(mSsl, SSL_VERIFY_PEER, NULL);
+	SSL_set_verify_depth(mSsl, 4);
+}
+
+void VerifiedTlsTransport::postHandshake() {
+	// Nothing to do
+}
+
+#endif
+
+} // namespace rtc
+
+#endif

src/verifiedtlstransport.hpp

@@ -0,0 +1,42 @@
+/**
+ * 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_VERIFIED_TLS_TRANSPORT_H
+#define RTC_VERIFIED_TLS_TRANSPORT_H
+
+#include "tlstransport.hpp"
+
+#if RTC_ENABLE_WEBSOCKET
+
+namespace rtc {
+
+class VerifiedTlsTransport final : public TlsTransport {
+public:
+	VerifiedTlsTransport(std::shared_ptr<TcpTransport> lower, string host, state_callback callback);
+	~VerifiedTlsTransport();
+
+protected:
+	void postCreation() override;
+	void postHandshake() override;
+};
+
+} // namespace rtc
+
+#endif
+
+#endif

src/websocket.cpp

@@ -18,11 +18,13 @@
 
 #if RTC_ENABLE_WEBSOCKET
 
-#include "include.hpp"
 #include "websocket.hpp"
+#include "include.hpp"
+#include "threadpool.hpp"
 
 #include "tcptransport.hpp"
 #include "tlstransport.hpp"
+#include "verifiedtlstransport.hpp"
 #include "wstransport.hpp"
 
 #include <regex>
@@ -33,7 +35,12 @@
 
 namespace rtc {
 
-WebSocket::WebSocket() { PLOG_VERBOSE << "Creating WebSocket"; }
+using std::shared_ptr;
+
+WebSocket::WebSocket(std::optional<Configuration> config)
+    : mConfig(config ? std::move(*config) : Configuration()) {
+	PLOG_VERBOSE << "Creating WebSocket";
+}
 
 WebSocket::~WebSocket() {
 	PLOG_VERBOSE << "Destroying WebSocket";
@@ -148,7 +155,7 @@ void WebSocket::incoming(message_ptr message) {
 	}
 }
 
-std::shared_ptr<TcpTransport> WebSocket::initTcpTransport() {
+shared_ptr<TcpTransport> WebSocket::initTcpTransport() {
 	using State = TcpTransport::State;
 	try {
 		std::lock_guard lock(mInitMutex);
@@ -193,7 +200,7 @@ std::shared_ptr<TcpTransport> WebSocket::initTcpTransport() {
 	}
 }
 
-std::shared_ptr<TlsTransport> WebSocket::initTlsTransport() {
+shared_ptr<TlsTransport> WebSocket::initTlsTransport() {
 	using State = TlsTransport::State;
 	try {
 		std::lock_guard lock(mInitMutex);
@@ -201,27 +208,40 @@ std::shared_ptr<TlsTransport> WebSocket::initTlsTransport() {
 			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;
-			    }
-		    });
+		auto stateChangeCallback = [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;
+			}
+		};
+
+		shared_ptr<TlsTransport> transport;
+#ifdef _WIN32
+		if (!mConfig.disableTlsVerification) {
+			PLOG_WARNING << "TLS certificate verification with root CA is not supported on Windows";
+		}
+		transport = std::make_shared<TlsTransport>(lower, mHost, stateChangeCallback);
+#else
+		if (mConfig.disableTlsVerification)
+			transport = std::make_shared<TlsTransport>(lower, mHost, stateChangeCallback);
+		else
+			transport = std::make_shared<VerifiedTlsTransport>(lower, mHost, stateChangeCallback);
+#endif
+
 		std::atomic_store(&mTlsTransport, transport);
 		if (mState == WebSocket::State::Closed) {
 			mTlsTransport.reset();
@@ -236,14 +256,14 @@ std::shared_ptr<TlsTransport> WebSocket::initTlsTransport() {
 	}
 }
 
-std::shared_ptr<WsTransport> WebSocket::initWsTransport() {
+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);
+		shared_ptr<Transport> lower = std::atomic_load(&mTlsTransport);
 		if (!lower)
 			lower = std::atomic_load(&mTcpTransport);
 		auto transport = std::make_shared<WsTransport>(
@@ -297,25 +317,22 @@ void WebSocket::closeTransports() {
 	// Reset callbacks now that state is changed
 	resetCallbacks();
 
-	// Pass the references to a thread, allowing to terminate a transport from its own thread
+	// Pass the pointers 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();
+	ThreadPool::Instance().enqueue([ws, tls, tcp]() mutable {
+		if (ws)
+			ws->stop();
+		if (tls)
+			tls->stop();
+		if (tcp)
+			tcp->stop();
 
-			ws.reset();
-			tls.reset();
-			tcp.reset();
-		});
-		t.detach();
-	}
+		ws.reset();
+		tls.reset();
+		tcp.reset();
+	});
 }
 
 } // namespace rtc

test/capi.cpp

@@ -200,7 +200,7 @@ int test_capi_main() {
 
 	// You may call rtcCleanup() when finished to free static resources
 	rtcCleanup();
-	sleep(1);
+	sleep(2);
 
 	printf("Success\n");
 	return 0;

test/connectivity.cpp

@@ -150,7 +150,7 @@ void test_connectivity() {
 
 	// You may call rtc::Cleanup() when finished to free static resources
 	rtc::Cleanup();
-	this_thread::sleep_for(1s);
+	this_thread::sleep_for(2s);
 
 	cout << "Success" << endl;
 }

test/main.cpp

@@ -18,6 +18,7 @@
 
 #include <chrono>
 #include <iostream>
+#include <thread>
 
 using namespace std;
 using namespace chrono_literals;
@@ -71,7 +72,10 @@ int main(int argc, char **argv) {
 		cout << "*** Finished WebRTC benchmark" << endl;
 	} catch (const exception &e) {
 		cerr << "WebRTC benchmark failed: " << e.what() << endl;
+		std::this_thread::sleep_for(2s);
 		return -1;
 	}
+
+	std::this_thread::sleep_for(2s);
 	return 0;
 }

test/websocket.cpp

@@ -38,6 +38,10 @@ void test_websocket() {
 
 	auto ws = std::make_shared<WebSocket>();
 
+	// Certificate verification can be disabled
+	// auto ws = std::make_shared<WebSocket>(WebSocket::Configuration{.disableTlsVerification =
+	// true});
+
 	ws->onOpen([wws = make_weak_ptr(ws), &myMessage]() {
 		auto ws = wws.lock();
 		if (!ws)
@@ -72,7 +76,7 @@ void test_websocket() {
 		throw runtime_error("Expected message not received");
 
 	ws->close();
-	this_thread::sleep_for(1s);
+	this_thread::sleep_for(2s);
 
 	// You may call rtc::Cleanup() when finished to free static resources
 	rtc::Cleanup();