Bumped version to v0.13.2

Fix possible static de-initialization order issue in SctpTransport

CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.7)
 project(libdatachannel
-	VERSION 0.13.0
+	VERSION 0.13.2
 	LANGUAGES CXX)
 set(PROJECT_DESCRIPTION "WebRTC Data Channels Library")
 
@@ -327,7 +327,7 @@ if(WARNINGS_AS_ERRORS)
 	endif()
 endif()
 
-install(TARGETS datachannel EXPORT datachannel-export
+install(TARGETS datachannel EXPORT libdatachannel-config
 	RUNTIME DESTINATION bin
 	LIBRARY DESTINATION lib
 	ARCHIVE DESTINATION lib
@@ -338,7 +338,7 @@ install(FILES ${LIBDATACHANNEL_HEADERS}
 )
 
 install(
-  EXPORT datachannel-export
+  EXPORT libdatachannel-config
   NAMESPACE LibDatachannel::
   DESTINATION share/cmake/libdatachannel
 )

src/candidate.cpp

@@ -93,7 +93,7 @@ void Candidate::parse(string candidate) {
 	                                        {"so", TransportType::TcpSo}};
 
 	const std::array prefixes{"a=", "candidate:"};
-	for (const string &prefix : prefixes)
+	for (string prefix : prefixes)
 		if (match_prefix(candidate, prefix))
 			candidate.erase(0, prefix.size());
 

src/impl/sctptransport.cpp

@@ -85,8 +85,30 @@ static LogCounter
 static LogCounter COUNTER_BAD_SCTP_STATUS(plog::warning,
                                           "Number of SCTP packets received with a bad status");
 
-std::unordered_set<SctpTransport *> SctpTransport::Instances;
+class SctpTransport::InstancesSet {
-std::shared_mutex SctpTransport::InstancesMutex;
+public:
+	void insert(SctpTransport *instance) {
+		std::unique_lock lock(mMutex);
+		mSet.insert(instance);
+	}
+
+	void erase(SctpTransport *instance) {
+		std::unique_lock lock(mMutex);
+		mSet.erase(instance);
+	}
+
+	using shared_lock = std::shared_lock<std::shared_mutex>;
+	optional<shared_lock> lock(SctpTransport *instance) {
+		shared_lock lock(mMutex);
+		return mSet.find(instance) != mSet.end() ? std::make_optional(std::move(lock)) : nullopt;
+	}
+
+private:
+	std::unordered_set<SctpTransport *> mSet;
+	std::shared_mutex mMutex;
+};
+
+SctpTransport::InstancesSet *SctpTransport::Instances = new InstancesSet;
 
 void SctpTransport::Init() {
 	usrsctp_init(0, &SctpTransport::WriteCallback, nullptr);
@@ -143,10 +165,7 @@ SctpTransport::SctpTransport(shared_ptr<Transport> lower, const Configuration &c
 	PLOG_DEBUG << "Initializing SCTP transport";
 
 	usrsctp_register_address(this);
-	{
+	Instances->insert(this);
-		std::unique_lock lock(InstancesMutex);
-		Instances.insert(this);
-	}
 
 	mSock = usrsctp_socket(AF_CONN, SOCK_STREAM, IPPROTO_SCTP, nullptr, nullptr, 0, nullptr);
 	if (!mSock)
@@ -285,10 +304,7 @@ SctpTransport::~SctpTransport() {
 	close();
 
 	usrsctp_deregister_address(this);
-	{
+	Instances->erase(this);
-		std::unique_lock lock(InstancesMutex);
-		Instances.erase(this);
-	}
 }
 
 void SctpTransport::start() {
@@ -416,9 +432,6 @@ void SctpTransport::incoming(message_ptr message) {
 
 	PLOG_VERBOSE << "Incoming size=" << message->size();
 
-	// TODO: There seems to be a possible data race between usrsctp_sendv() and usrsctp_conninput()
-	// As a mitigation, lock the send mutex before calling usrsctp_conninput()
-	std::lock_guard lock(mSendMutex);
 	usrsctp_conninput(this, message->data(), message->size(), 0);
 }
 
@@ -851,11 +864,8 @@ optional<milliseconds> SctpTransport::rtt() {
 void SctpTransport::UpcallCallback(struct socket *, void *arg, int /* flags */) {
 	auto *transport = static_cast<SctpTransport *>(arg);
 
-	std::shared_lock lock(InstancesMutex);
+	if(auto lock = Instances->lock(transport))
-	if (Instances.find(transport) == Instances.end())
+		transport->handleUpcall();
-		return;
-
-	transport->handleUpcall();
 }
 
 int SctpTransport::WriteCallback(void *ptr, void *data, size_t len, uint8_t tos, uint8_t set_df) {
@@ -863,11 +873,10 @@ int SctpTransport::WriteCallback(void *ptr, void *data, size_t len, uint8_t tos,
 
 	// 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(auto lock = Instances->lock(transport))
-	if (Instances.find(transport) == Instances.end())
+		return transport->handleWrite(static_cast<byte *>(data), len, tos, set_df);
+	else
 		return -1;
-
-	return transport->handleWrite(static_cast<byte *>(data), len, tos, set_df);
 }
 
 } // namespace rtc::impl

src/impl/sctptransport.hpp

@@ -120,8 +120,8 @@ private:
 	static void UpcallCallback(struct socket *sock, void *arg, int flags);
 	static int WriteCallback(void *sctp_ptr, void *data, size_t len, uint8_t tos, uint8_t set_df);
 
-	static std::unordered_set<SctpTransport *> Instances;
+	class InstancesSet;
-	static std::shared_mutex InstancesMutex;
+	static InstancesSet *Instances;
 };
 
 } // namespace rtc::impl