Merge 32a70562c4 into 0086f8e27a

hardening iterator

daemon/UPnP.cpp

@@ -122,7 +122,7 @@ namespace transport
 		err = UPNP_GetValidIGD (m_Devlist, &m_upnpUrls, &m_upnpData, m_NetworkAddr, sizeof (m_NetworkAddr));
 #endif
 		m_upnpUrlsInitialized=err!=0;
-		if (err == UPNP_IGD_VALID_CONNECTED)
+		if (err == UPNP_IGD_VALID_CONNECTED || err == UPNP_IGD_VALID_NOT_CONNECTED)
 		{
 #if (MINIUPNPC_API_VERSION < 18)
 			err = UPNP_GetExternalIPAddress (m_upnpUrls.controlURL, m_upnpData.first.servicetype, m_externalIPAddress);

daemon/UnixDaemon.cpp

@@ -221,7 +221,7 @@ namespace i2p
 
 		void DaemonLinux::run ()
 		{
-			i2p::util::SetThreadName ("Daemon");
+			i2p::util::SetThreadName ("i2pd-daemon");
 			while (running)
 			{
 				std::this_thread::sleep_for (std::chrono::seconds(1));

libi2pd/HTTP.cpp

@@ -103,6 +103,7 @@ namespace http
 
 	bool URL::parse(std::string_view url) 
 	{
+		if (url.empty ()) return false;
 		std::size_t pos_p = 0; /* < current parse position */
 		std::size_t pos_c = 0; /* < work position */
 		if(url.at(0) != '/' || pos_p > 0) 

libi2pd/I2NPProtocol.cpp

@@ -396,8 +396,26 @@ namespace i2p
 					return false;
 				}	
 				uint8_t retCode = 0;
+				// decide if we should accept tunnel
+				bool accept = i2p::context.AcceptsTunnels ();
+				if (accept)
+				{
+					auto congestionLevel = i2p::context.GetCongestionLevel (false);
+					if (congestionLevel >= CONGESTION_LEVEL_MEDIUM)
+					{	
+						if (congestionLevel < CONGESTION_LEVEL_FULL)
+						{
+							// random reject depending on congestion level
+							int level = i2p::tunnel::tunnels.GetRng ()() % (CONGESTION_LEVEL_FULL - CONGESTION_LEVEL_MEDIUM) + CONGESTION_LEVEL_MEDIUM;
+							if (congestionLevel > level)
+								accept = false;
+						}	
+						else	
+							accept = false;
+					}	
+				}	
 				// replace record to reply
-				if (i2p::context.AcceptsTunnels () && i2p::context.GetCongestionLevel (false) < CONGESTION_LEVEL_FULL)
+				if (accept)
 				{
 					auto transitTunnel = i2p::tunnel::CreateTransitTunnel (
 							bufbe32toh (clearText + ECIES_BUILD_REQUEST_RECORD_RECEIVE_TUNNEL_OFFSET),

libi2pd/NTCP2.cpp

@@ -375,6 +375,8 @@ namespace transport
 			m_Socket.close ();
 			transports.PeerDisconnected (shared_from_this ());
 			m_Server.RemoveNTCP2Session (shared_from_this ());
+			if (!m_IntermediateQueue.empty ())
+				m_SendQueue.splice (m_SendQueue.end (), m_IntermediateQueue);
 			for (auto& it: m_SendQueue)
 				it->Drop ();
 			m_SendQueue.clear ();
@@ -1207,7 +1209,7 @@ namespace transport
 	void NTCP2Session::MoveSendQueue (std::shared_ptr<NTCP2Session> other)
 	{
 		if (!other || m_SendQueue.empty ()) return;
-		std::vector<std::shared_ptr<I2NPMessage> > msgs;
+		std::list<std::shared_ptr<I2NPMessage> > msgs;
 		auto ts = i2p::util::GetMillisecondsSinceEpoch ();
 		for (auto it: m_SendQueue)
 			if (!it->IsExpired (ts))
@@ -1216,7 +1218,7 @@ namespace transport
 				it->Drop ();
 		m_SendQueue.clear ();
 		if (!msgs.empty ())
-			other->PostI2NPMessages (msgs);
+			other->SendI2NPMessages (msgs);
 	}	
 		
 	size_t NTCP2Session::CreatePaddingBlock (size_t msgLen, uint8_t * buf, size_t len)
@@ -1297,20 +1299,42 @@ namespace transport
 		m_Server.GetService ().post (std::bind (&NTCP2Session::Terminate, shared_from_this ())); // let termination message go
 	}
 
-	void NTCP2Session::SendI2NPMessages (const std::vector<std::shared_ptr<I2NPMessage> >& msgs)
+	void NTCP2Session::SendI2NPMessages (std::list<std::shared_ptr<I2NPMessage> >& msgs)
 	{
-		m_Server.GetService ().post (std::bind (&NTCP2Session::PostI2NPMessages, shared_from_this (), msgs));
+		if (m_IsTerminated || msgs.empty ()) 
+		{
+			msgs.clear ();
+			return;
+		}	
+		bool empty = false;
+		{
+			std::lock_guard<std::mutex> l(m_IntermediateQueueMutex);
+			empty = m_IntermediateQueue.empty ();
+			m_IntermediateQueue.splice (m_IntermediateQueue.end (), msgs);
+		}
+		if (empty)
+			m_Server.GetService ().post (std::bind (&NTCP2Session::PostI2NPMessages, shared_from_this ()));
 	}
 
-	void NTCP2Session::PostI2NPMessages (std::vector<std::shared_ptr<I2NPMessage> > msgs)
+	void NTCP2Session::PostI2NPMessages ()
 	{
 		if (m_IsTerminated) return;
+		std::list<std::shared_ptr<I2NPMessage> > msgs;
+		{
+			std::lock_guard<std::mutex> l(m_IntermediateQueueMutex);
+			m_IntermediateQueue.swap (msgs);		
+		}	
 		bool isSemiFull = m_SendQueue.size () > NTCP2_MAX_OUTGOING_QUEUE_SIZE/2;
+		if (isSemiFull)
+		{	
 			for (auto it: msgs)
-			if (isSemiFull && it->onDrop)
+				if (it->onDrop)
 					it->Drop (); // drop earlier because we can handle it
 				else
 					m_SendQueue.push_back (std::move (it));
+		}	
+		else
+			m_SendQueue.splice (m_SendQueue.end (), msgs);
 		
 		if (!m_IsSending && m_IsEstablished)
 			SendQueue ();
@@ -1822,7 +1846,7 @@ namespace transport
 							LogPrint(eLogError, "NTCP2: HTTP proxy write error ", ec.message());
 					});
 
-				boost::asio::streambuf * readbuff = new boost::asio::streambuf;
+				auto readbuff = std::make_shared<boost::asio::streambuf>();
 				boost::asio::async_read_until(conn->GetSocket(), *readbuff, "\r\n\r\n",
 					[readbuff, timer, conn] (const boost::system::error_code & ec, std::size_t transferred)
 					{
@@ -1842,7 +1866,6 @@ namespace transport
 								{
 									timer->cancel();
 									conn->ClientLogin();
-									delete readbuff;
 									return;
 								}
 								else
@@ -1852,7 +1875,6 @@ namespace transport
 								LogPrint(eLogError, "NTCP2: HTTP proxy gave malformed response");
 							timer->cancel();
 							conn->Terminate();
-							delete readbuff;
 						}
 					});
 				break;

libi2pd/NTCP2.h

@@ -153,7 +153,7 @@ namespace transport
 			void ServerLogin (); // Bob
 
 			void SendLocalRouterInfo (bool update) override; // after handshake or by update
-			void SendI2NPMessages (const std::vector<std::shared_ptr<I2NPMessage> >& msgs) override;
+			void SendI2NPMessages (std::list<std::shared_ptr<I2NPMessage> >& msgs) override;
 			void MoveSendQueue (std::shared_ptr<NTCP2Session> other);
 			
 		private:
@@ -196,7 +196,7 @@ namespace transport
 			void SendRouterInfo ();
 			void SendTermination (NTCP2TerminationReason reason);
 			void SendTerminationAndTerminate (NTCP2TerminationReason reason);
-			void PostI2NPMessages (std::vector<std::shared_ptr<I2NPMessage> > msgs);
+			void PostI2NPMessages ();
 
 		private:
 
@@ -230,6 +230,9 @@ namespace transport
 			std::list<std::shared_ptr<I2NPMessage> > m_SendQueue;
 			uint64_t m_NextRouterInfoResendTime; // seconds since epoch
 			
+			std::list<std::shared_ptr<I2NPMessage> > m_IntermediateQueue; // from transports
+			mutable std::mutex m_IntermediateQueueMutex;
+			
 			uint16_t m_PaddingSizes[16];
 			int m_NextPaddingSize;
 	};

libi2pd/NetDb.cpp

@@ -480,7 +480,7 @@ namespace data
 	void NetDb::ReseedFromFloodfill(const RouterInfo & ri, int numRouters, int numFloodfills)
 	{
 		LogPrint(eLogInfo, "NetDB: Reseeding from floodfill ", ri.GetIdentHashBase64());
-		std::vector<std::shared_ptr<i2p::I2NPMessage> > requests;
+		std::list<std::shared_ptr<i2p::I2NPMessage> > requests;
 
 		i2p::data::IdentHash ourIdent = i2p::context.GetIdentHash();
 		i2p::data::IdentHash ih = ri.GetIdentHash();

libi2pd/RouterContext.cpp

@@ -1489,7 +1489,7 @@ namespace i2p
 	void RouterContext::UpdateCongestion ()
 	{
 		auto c = i2p::data::RouterInfo::eLowCongestion;
-		if (!AcceptsTunnels () || !m_ShareRatio)
+		if (!AcceptsTunnels () || !m_ShareRatio || (m_Error == eRouterErrorSymmetricNAT && !SupportsV6 () && !SupportsMesh ()))                                        	
 			c = i2p::data::RouterInfo::eRejectAll;
 		else
 		{

libi2pd/SSU2.cpp

@@ -477,7 +477,7 @@ namespace transport
 		HandleReceivedPackets (std::move (receivedPackets));
 	}	
 		
-	void SSU2Server::AddSession (std::shared_ptr<SSU2Session> session)
+	bool SSU2Server::AddSession (std::shared_ptr<SSU2Session> session)
 	{
 		if (session)
 		{
@@ -485,8 +485,10 @@ namespace transport
 			{	
 				if (session->GetState () != eSSU2SessionStatePeerTest)
 					AddSessionByRouterHash (session);
+				return true;
 			}	
 		}
+		return false;
 	}
 
 	void SSU2Server::RemoveSession (uint64_t connID)

libi2pd/SSU2.h

@@ -42,8 +42,8 @@ namespace transport
 	const int SSU2_KEEP_ALIVE_INTERVAL = 15; // in seconds
 	const int SSU2_KEEP_ALIVE_INTERVAL_VARIANCE = 4; // in seconds
 	const int SSU2_PROXY_CONNECT_RETRY_TIMEOUT = 30; // in seconds
-	const int SSU2_MIN_HOLE_PUNCH_EXPIRATION = 45; // in seconds
+	const int SSU2_MIN_HOLE_PUNCH_EXPIRATION = 30; // in seconds
-	const int SSU2_MAX_HOLE_PUNCH_EXPIRATION = 181; // in seconds
+	const int SSU2_MAX_HOLE_PUNCH_EXPIRATION = 160; // in seconds
 	const size_t SSU2_MAX_NUM_PACKETS_PER_BATCH = 64;
 
 	class SSU2Server: private i2p::util::RunnableServiceWithWork
@@ -85,7 +85,7 @@ namespace transport
 			bool IsSyncClockFromPeers () const { return m_IsSyncClockFromPeers; };
 			void AdjustTimeOffset (int64_t offset, std::shared_ptr<const i2p::data::IdentityEx> from);
 
-			void AddSession (std::shared_ptr<SSU2Session> session);
+			bool AddSession (std::shared_ptr<SSU2Session> session);
 			void RemoveSession (uint64_t connID);
 			void RequestRemoveSession (uint64_t connID);
 			void AddSessionByRouterHash (std::shared_ptr<SSU2Session> session);

libi2pd/SSU2Session.cpp

@@ -83,7 +83,7 @@ namespace transport
 		std::shared_ptr<const i2p::data::RouterInfo::Address> addr, bool noise):
 		TransportSession (in_RemoteRouter, SSU2_CONNECT_TIMEOUT),
 		m_Server (server), m_Address (addr), m_RemoteTransports (0), m_RemotePeerTestTransports (0),
-		m_DestConnID (0), m_SourceConnID (0), m_State (eSSU2SessionStateUnknown),
+		m_RemoteVersion (0), m_DestConnID (0), m_SourceConnID (0), m_State (eSSU2SessionStateUnknown),
 		m_SendPacketNum (0), m_ReceivePacketNum (0), m_LastDatetimeSentPacketNum (0),
 		m_IsDataReceived (false), m_RTT (SSU2_UNKNOWN_RTT),
 		m_MsgLocalExpirationTimeout (I2NP_MESSAGE_LOCAL_EXPIRATION_TIMEOUT_MAX),
@@ -103,6 +103,7 @@ namespace transport
 				InitNoiseXKState1 (*m_NoiseState, m_Address->s);
 			m_RemoteEndpoint = boost::asio::ip::udp::endpoint (m_Address->host, m_Address->port);
 			m_RemoteTransports = in_RemoteRouter->GetCompatibleTransports (false);
+			m_RemoteVersion = in_RemoteRouter->GetVersion ();
 			if (in_RemoteRouter->IsSSU2PeerTesting (true)) m_RemotePeerTestTransports |= i2p::data::RouterInfo::eSSU2V4;
 			if (in_RemoteRouter->IsSSU2PeerTesting (false)) m_RemotePeerTestTransports |= i2p::data::RouterInfo::eSSU2V6;
 			RAND_bytes ((uint8_t *)&m_DestConnID, 8);
@@ -292,6 +293,8 @@ namespace transport
 			m_SentHandshakePacket.reset (nullptr);
 			m_SessionConfirmedFragment.reset (nullptr);
 			m_PathChallenge.reset (nullptr);
+			if (!m_IntermediateQueue.empty ())
+				m_SendQueue.splice (m_SendQueue.end (), m_IntermediateQueue);
 			for (auto& it: m_SendQueue)
 				it->Drop ();
 			m_SendQueue.clear ();
@@ -371,14 +374,31 @@ namespace transport
 
 	}
 
-	void SSU2Session::SendI2NPMessages (const std::vector<std::shared_ptr<I2NPMessage> >& msgs)
+	void SSU2Session::SendI2NPMessages (std::list<std::shared_ptr<I2NPMessage> >& msgs)
 	{
-		m_Server.GetService ().post (std::bind (&SSU2Session::PostI2NPMessages, shared_from_this (), msgs));
+		if (m_State == eSSU2SessionStateTerminated || msgs.empty ()) 
+		{
+			msgs.clear ();
+			return;
+		}	
+		bool empty = false;
+		{
+			std::lock_guard<std::mutex> l(m_IntermediateQueueMutex);
+			empty = m_IntermediateQueue.empty ();
+			m_IntermediateQueue.splice (m_IntermediateQueue.end (), msgs);
+		}
+		if (empty)
+			m_Server.GetService ().post (std::bind (&SSU2Session::PostI2NPMessages, shared_from_this ()));
 	}
 
-	void SSU2Session::PostI2NPMessages (std::vector<std::shared_ptr<I2NPMessage> > msgs)
+	void SSU2Session::PostI2NPMessages ()
 	{
 		if (m_State == eSSU2SessionStateTerminated) return;
+		std::list<std::shared_ptr<I2NPMessage> > msgs;
+		{
+			std::lock_guard<std::mutex> l(m_IntermediateQueueMutex);
+			m_IntermediateQueue.swap (msgs);		
+		}	
 		uint64_t mts = i2p::util::GetMonotonicMicroseconds ();
 		bool isSemiFull = false;
 		if (m_SendQueue.size ())
@@ -392,9 +412,11 @@ namespace transport
 					" is semi-full (size = ", m_SendQueue.size (), ", lag = ", queueLag / 1000, ", rtt = ", (int)m_RTT, ")");
 			}
 		}
+		if (isSemiFull)
+		{	
 			for (auto it: msgs)
 			{
-			if (isSemiFull && it->onDrop)
+				if (it->onDrop)
 					it->Drop (); // drop earlier because we can handle it
 				else
 				{
@@ -402,6 +424,12 @@ namespace transport
 					m_SendQueue.push_back (std::move (it));
 				}
 			}
+		}	
+		else
+		{
+			for (auto& it: msgs) it->SetEnqueueTime (mts);
+			m_SendQueue.splice (m_SendQueue.end (), msgs);
+		}	
 		if (IsEstablished ())
 		{	
 			SendQueue ();
@@ -414,7 +442,7 @@ namespace transport
 	void SSU2Session::MoveSendQueue (std::shared_ptr<SSU2Session> other)
 	{
 		if (!other || m_SendQueue.empty ()) return;
-		std::vector<std::shared_ptr<I2NPMessage> > msgs;
+		std::list<std::shared_ptr<I2NPMessage> > msgs;
 		auto ts = i2p::util::GetMillisecondsSinceEpoch ();
 		for (auto it: m_SendQueue)
 			if (!it->IsExpired (ts))
@@ -423,7 +451,7 @@ namespace transport
 				it->Drop ();
 		m_SendQueue.clear ();
 		if (!msgs.empty ())
-			other->PostI2NPMessages (msgs);
+			other->SendI2NPMessages (msgs);
 	}	
 		
 	bool SSU2Session::SendQueue ()
@@ -1185,6 +1213,7 @@ namespace transport
 		m_RemotePeerTestTransports = 0;
 		if (ri->IsSSU2PeerTesting (true)) m_RemotePeerTestTransports |= i2p::data::RouterInfo::eSSU2V4;
 		if (ri->IsSSU2PeerTesting (false)) m_RemotePeerTestTransports |= i2p::data::RouterInfo::eSSU2V6;
+		m_RemoteVersion = ri->GetVersion ();
 		
 		// handle other blocks
 		HandlePayload (decryptedPayload.data () + riSize + 3, decryptedPayload.size () - riSize - 3);
@@ -1929,9 +1958,9 @@ namespace transport
 			return;
 		}
 		auto mts = i2p::util::GetMillisecondsSinceEpoch ();
-		session->m_RelaySessions.emplace (bufbe32toh (buf + 1), // nonce
+		uint32_t nonce = bufbe32toh (buf + 1);
-			std::make_pair (shared_from_this (), mts/1000) );
+		if (session->m_RelaySessions.emplace (nonce, std::make_pair (shared_from_this (), mts/1000)).second)
-
+		{
 			// send relay intro to Charlie
 			auto r = i2p::data::netdb.FindRouter (GetRemoteIdentity ()->GetIdentHash ()); // Alice's RI
 			if (r && (r->IsUnreachable () || !i2p::data::netdb.PopulateRouterInfoBuffer (r))) r = nullptr;
@@ -1949,6 +1978,9 @@ namespace transport
 			// Charlie always responds with RelayResponse
 			session->m_SentPackets.emplace (packetNum, packet);
 		}
+		else
+			LogPrint (eLogInfo, "SSU2: Relay request nonce ", nonce, " already exists. Ignore");
+	}
 
 	void SSU2Session::HandleRelayIntro (const uint8_t * buf, size_t len, int attempts)
 	{
@@ -2033,15 +2065,22 @@ namespace transport
 		{
 			// send HolePunch 
 			auto holePunchSession = std::make_shared<SSU2HolePunchSession>(m_Server, nonce, ep, addr); 
-			m_Server.AddSession (holePunchSession);
+			if (m_Server.AddSession (holePunchSession))
 				holePunchSession->SendHolePunch (packet->payload, packet->payloadSize); // relay response block
+			else
+			{
+				LogPrint (eLogInfo, "SSU2: Relay intro nonce ", nonce, " already exists. Ignore");
+				return;
+			}		
 		}	
 		packet->payloadSize += CreatePaddingBlock (packet->payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
-		/*uint32_t packetNum = */SendData (packet->payload, packet->payloadSize);
+		uint32_t packetNum = SendData (packet->payload, packet->payloadSize);
-		// sometimes Bob doesn't ack this RelayResponse
+		if (m_RemoteVersion >= SSU2_MIN_RELAY_RESPONSE_RESEND_VERSION)
-		// TODO: uncomment line below once the problem is resolved
+		{	
-		//packet->sendTime = mts;
+			// sometimes Bob doesn't ack this RelayResponse in older versions
-		//m_SentPackets.emplace (packetNum, packet);
+			packet->sendTime = i2p::util::GetMillisecondsSinceEpoch ();
+			m_SentPackets.emplace (packetNum, packet);
+		}	
 	}
 
 	void SSU2Session::HandleRelayResponse (const uint8_t * buf, size_t len)
@@ -2076,11 +2115,13 @@ namespace transport
 				memcpy (payload + 3, buf, len); // forward to Alice as is
 				packet->payloadSize = len + 3;
 				packet->payloadSize += CreatePaddingBlock (payload + packet->payloadSize, m_MaxPayloadSize - packet->payloadSize);
-				/*uint32_t packetNum = */it->second.first->SendData (packet->payload, packet->payloadSize);
+				uint32_t packetNum = it->second.first->SendData (packet->payload, packet->payloadSize);
-				// sometimes Alice doesn't ack this RelayResponse
+				if (m_RemoteVersion >= SSU2_MIN_RELAY_RESPONSE_RESEND_VERSION)
-				// TODO: uncomment line below once the problem is resolved
+				{	
-				//packet->sendTime = i2p::util::GetMillisecondsSinceEpoch ();
+					// sometimes Alice doesn't ack this RelayResponse in older versions
-				//it->second.first->m_SentPackets.emplace (packetNum, packet);
+					packet->sendTime = i2p::util::GetMillisecondsSinceEpoch ();
+					it->second.first->m_SentPackets.emplace (packetNum, packet);
+				}	
 			}
 			else
 			{
@@ -2148,7 +2189,8 @@ namespace transport
 					GetRemoteIdentity ()->GetIdentHash ());
 				if (session) // session with Charlie
 				{
-					m_Server.AddPeerTest (nonce, shared_from_this (), ts/1000);
+					if (m_Server.AddPeerTest (nonce, shared_from_this (), ts/1000))
+					{	
 						auto packet = m_Server.GetSentPacketsPool ().AcquireShared ();
 						// Alice's RouterInfo
 						auto r = i2p::data::netdb.FindRouter (GetRemoteIdentity ()->GetIdentHash ());
@@ -2172,6 +2214,9 @@ namespace transport
 						packet->sendTime = ts;
 						session->m_SentPackets.emplace (packetNum, packet);
 					}
+					else
+						LogPrint (eLogInfo, "SSU2: Peer test 1 nonce ", nonce, " already exists. Ignored");
+				}
 				else
 				{
 					// Charlie not found, send error back to Alice
@@ -3037,7 +3082,7 @@ namespace transport
 		{
 			if (ts > it->second.second + SSU2_RELAY_NONCE_EXPIRATION_TIMEOUT)
 			{
-				LogPrint (eLogWarning, "SSU2: Relay nonce ", it->first, " was not responded in ", SSU2_RELAY_NONCE_EXPIRATION_TIMEOUT, " seconds, deleted");
+				LogPrint (eLogInfo, "SSU2: Relay nonce ", it->first, " was not responded in ", SSU2_RELAY_NONCE_EXPIRATION_TIMEOUT, " seconds, deleted");
 				it = m_RelaySessions.erase (it);
 			}
 			else

libi2pd/SSU2Session.h

@@ -15,6 +15,7 @@
 #include <set>
 #include <list>
 #include <boost/asio.hpp>
+#include "version.h"
 #include "Crypto.h"
 #include "RouterInfo.h"
 #include "RouterContext.h"
@@ -55,6 +56,7 @@ namespace transport
 	const int SSU2_MAX_NUM_ACK_RANGES = 32; // to send
 	const uint8_t SSU2_MAX_NUM_FRAGMENTS = 64;
 	const int SSU2_SEND_DATETIME_NUM_PACKETS = 256;
+	const int SSU2_MIN_RELAY_RESPONSE_RESEND_VERSION = MAKE_VERSION_NUMBER(0, 9, 64); // 0.9.64
 
 	// flags
 	const uint8_t SSU2_FLAG_IMMEDIATE_ACK_REQUESTED = 0x01;
@@ -259,7 +261,7 @@ namespace transport
 			void FlushData ();
 			void Done () override;
 			void SendLocalRouterInfo (bool update) override;
-			void SendI2NPMessages (const std::vector<std::shared_ptr<I2NPMessage> >& msgs) override;
+			void SendI2NPMessages (std::list<std::shared_ptr<I2NPMessage> >& msgs) override;
 			void MoveSendQueue (std::shared_ptr<SSU2Session> other);
 			uint32_t GetRelayTag () const override { return m_RelayTag; };
 			size_t Resend (uint64_t ts); // return number of resent packets
@@ -305,7 +307,7 @@ namespace transport
 			void Established ();
 			void ScheduleConnectTimer ();
 			void HandleConnectTimer (const boost::system::error_code& ecode);
-			void PostI2NPMessages (std::vector<std::shared_ptr<I2NPMessage> > msgs);
+			void PostI2NPMessages ();
 			bool SendQueue (); // returns true if ack block was sent
 			bool SendFragmentedMessage (std::shared_ptr<I2NPMessage> msg);
 			void ResendHandshakePacket ();
@@ -368,6 +370,7 @@ namespace transport
 			std::shared_ptr<const i2p::data::RouterInfo::Address> m_Address;
 			boost::asio::ip::udp::endpoint m_RemoteEndpoint;
 			i2p::data::RouterInfo::CompatibleTransports m_RemoteTransports, m_RemotePeerTestTransports; 
+			int m_RemoteVersion;
 			uint64_t m_DestConnID, m_SourceConnID;
 			SSU2SessionState m_State;
 			uint8_t m_KeyDataSend[64], m_KeyDataReceive[64];
@@ -378,6 +381,8 @@ namespace transport
 			std::unordered_map<uint32_t, std::pair <std::shared_ptr<SSU2Session>, uint64_t > > m_RelaySessions; // nonce->(Alice, timestamp) for Bob or nonce->(Charlie, timestamp) for Alice
 			std::list<std::shared_ptr<I2NPMessage> > m_SendQueue;
 			i2p::I2NPMessagesHandler m_Handler;
+			std::list<std::shared_ptr<I2NPMessage> > m_IntermediateQueue; // from transports
+			mutable std::mutex m_IntermediateQueueMutex;
 			bool m_IsDataReceived;
 			double m_RTT;
 			int m_MsgLocalExpirationTimeout;

libi2pd/Streaming.cpp

@@ -1237,7 +1237,8 @@ namespace stream
 		if (m_Status != eStreamStatusTerminated)
 		{
 			m_SendTimer.cancel ();
-			m_SendTimer.expires_from_now (boost::posix_time::microseconds(SEND_INTERVAL));
+			m_SendTimer.expires_from_now (boost::posix_time::microseconds(
+				SEND_INTERVAL + m_LocalDestination.GetRandom () % SEND_INTERVAL_VARIANCE));
 			m_SendTimer.async_wait (std::bind (&Stream::HandleSendTimer,
 				shared_from_this (), std::placeholders::_1));
 		}
@@ -1250,8 +1251,17 @@ namespace stream
 			auto ts = i2p::util::GetMillisecondsSinceEpoch ();
 			if (m_LastSendTime && ts*1000 > m_LastSendTime*1000 + m_PacingTime)
 			{
-				m_NumPacketsToSend = ((ts*1000 - m_LastSendTime*1000) + m_PacingTimeRem) / m_PacingTime;
+				if (m_PacingTime)
-				m_PacingTimeRem = ((ts*1000 - m_LastSendTime*1000) + m_PacingTimeRem) - (m_NumPacketsToSend * m_PacingTime);
+				{	
+					auto numPackets = std::lldiv (m_PacingTimeRem + ts*1000 - m_LastSendTime*1000, m_PacingTime);
+					m_NumPacketsToSend = numPackets.quot;
+					m_PacingTimeRem = numPackets.rem;
+				}	
+				else
+				{
+					LogPrint (eLogError, "Streaming: pacing time is zero");
+					m_NumPacketsToSend = 1; m_PacingTimeRem = 0;
+				}	
 				m_IsSendTime = true;
 				if (m_WindowIncCounter && m_WindowSize < MAX_WINDOW_SIZE && !m_SendBuffer.IsEmpty () && m_PacingTime > m_MinPacingTime)
 				{
@@ -1267,10 +1277,12 @@ namespace stream
 								m_WindowSize += (m_WindowSize - (1 - PREV_SPEED_KEEP_TIME_COEFF)) / m_WindowSize;
 							if (m_WindowSize > MAX_WINDOW_SIZE) m_WindowSize = MAX_WINDOW_SIZE;
 							m_WindowIncCounter--;
+						}
+						else
+							break;
+					}
 					UpdatePacingTime ();
 				}
-					}
-				}
 				if (m_IsNAcked)
 					ResendPacket ();
 				else if (m_IsResendNeeded) // resend packets

libi2pd/Streaming.h

@@ -69,7 +69,8 @@ namespace stream
 	const int PENDING_INCOMING_TIMEOUT = 10; // in seconds
 	const int MAX_RECEIVE_TIMEOUT = 20; // in seconds
 	const uint16_t DELAY_CHOKING = 60000; // in milliseconds
-	const uint64_t SEND_INTERVAL = 1000; // in microseconds
+	const uint64_t SEND_INTERVAL = 10000; // in microseconds
+	const uint64_t SEND_INTERVAL_VARIANCE = 2000; // in microseconds
 	const uint64_t REQUEST_IMMEDIATE_ACK_INTERVAL = 7500; // in milliseconds 
 	const uint64_t REQUEST_IMMEDIATE_ACK_INTERVAL_VARIANCE = 3200; // in milliseconds 	
 	const bool LOSS_BASED_CONTROL_ENABLED = 1; // 0/1

libi2pd/TransitTunnel.cpp

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2022, The PurpleI2P Project
+* Copyright (c) 2013-2024, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *
@@ -59,8 +59,7 @@ namespace tunnel
 			auto num = m_TunnelDataMsgs.size ();
 			if (num > 1)
 				LogPrint (eLogDebug, "TransitTunnel: ", GetTunnelID (), "->", GetNextTunnelID (), " ", num);
-			i2p::transport::transports.SendMessages (GetNextIdentHash (), m_TunnelDataMsgs);
+			i2p::transport::transports.SendMessages (GetNextIdentHash (), m_TunnelDataMsgs); // send and clear
-			m_TunnelDataMsgs.clear ();
 		}
 	}
 

libi2pd/TransitTunnel.h

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2023, The PurpleI2P Project
+* Copyright (c) 2013-2024, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *
@@ -10,7 +10,7 @@
 #define TRANSIT_TUNNEL_H__
 
 #include <inttypes.h>
-#include <vector>
+#include <list>
 #include <mutex>
 #include <memory>
 #include "Crypto.h"
@@ -61,7 +61,7 @@ namespace tunnel
 		private:
 
 			size_t m_NumTransmittedBytes;
-			std::vector<std::shared_ptr<i2p::I2NPMessage> > m_TunnelDataMsgs;
+			std::list<std::shared_ptr<i2p::I2NPMessage> > m_TunnelDataMsgs;
 	};
 
 	class TransitTunnelGateway: public TransitTunnel

libi2pd/TransportSession.h

@@ -144,8 +144,12 @@ namespace transport
 			void SetLastActivityTimestamp (uint64_t ts) { m_LastActivityTimestamp = ts; };
 			
 			virtual uint32_t GetRelayTag () const { return 0; };
-			virtual void SendLocalRouterInfo (bool update = false) { SendI2NPMessages ({ CreateDatabaseStoreMsg () }); };
+			virtual void SendLocalRouterInfo (bool update = false) 
-			virtual void SendI2NPMessages (const std::vector<std::shared_ptr<I2NPMessage> >& msgs) = 0;
+			{
+				std::list<std::shared_ptr<I2NPMessage> > msgs{ CreateDatabaseStoreMsg () };
+				SendI2NPMessages (msgs); 
+			};
+			virtual void SendI2NPMessages (std::list<std::shared_ptr<I2NPMessage> >& msgs) = 0;
 			virtual bool IsEstablished () const = 0;
 
 		private:

libi2pd/Transports.cpp

@@ -450,15 +450,25 @@ namespace transport
 	void Transports::SendMessage (const i2p::data::IdentHash& ident, std::shared_ptr<i2p::I2NPMessage> msg)
 	{
 		if (m_IsOnline)
-			SendMessages (ident, std::vector<std::shared_ptr<i2p::I2NPMessage> > {msg });
+			SendMessages (ident, { msg });
 	}
 
-	void Transports::SendMessages (const i2p::data::IdentHash& ident, const std::vector<std::shared_ptr<i2p::I2NPMessage> >& msgs)
+	void Transports::SendMessages (const i2p::data::IdentHash& ident, std::list<std::shared_ptr<i2p::I2NPMessage> >& msgs)
 	{
-		m_Service->post (std::bind (&Transports::PostMessages, this, ident, msgs));
+		std::list<std::shared_ptr<i2p::I2NPMessage> > msgs1;
+		msgs.swap (msgs1);
+		SendMessages (ident, std::move (msgs1));
 	}
 
-	void Transports::PostMessages (i2p::data::IdentHash ident, std::vector<std::shared_ptr<i2p::I2NPMessage> > msgs)
+	void Transports::SendMessages (const i2p::data::IdentHash& ident, std::list<std::shared_ptr<i2p::I2NPMessage> >&& msgs)
+	{
+		m_Service->post ([this, ident, msgs = std::move(msgs)] () mutable
+			{
+				PostMessages (ident, msgs);
+			});	
+	}	
+	
+	void Transports::PostMessages (const i2p::data::IdentHash& ident, std::list<std::shared_ptr<i2p::I2NPMessage> >& msgs)
 	{
 		if (ident == i2p::context.GetRouterInfo ().GetIdentHash ())
 		{
@@ -517,12 +527,17 @@ namespace transport
 						return;
 					}	
 				}	
+				if (sz > MAX_NUM_DELAYED_MESSAGES/2)
+				{	
 					for (auto& it1: msgs)
-					if (sz > MAX_NUM_DELAYED_MESSAGES/2 && it1->onDrop)
+						if (it1->onDrop)
 							it1->Drop (); // drop earlier because we can handle it
 						else
 							peer->delayedMessages.push_back (it1);
 				}	
+				else
+					peer->delayedMessages.splice (peer->delayedMessages.end (), msgs);
+			}
 			else
 			{
 				LogPrint (eLogWarning, "Transports: Delayed messages queue size to ",
@@ -865,7 +880,7 @@ namespace transport
 				if (it->second->delayedMessages.size () > 0)
 				{
 					// check if first message is our DatabaseStore (publishing)
-					auto firstMsg = peer->delayedMessages[0];
+					auto firstMsg = peer->delayedMessages.front ();
 					if (firstMsg && firstMsg->GetTypeID () == eI2NPDatabaseStore &&
 							i2p::data::IdentHash(firstMsg->GetPayload () + DATABASE_STORE_KEY_OFFSET) == i2p::context.GetIdentHash ())
 						sendDatabaseStore = false; // we have it in the list already
@@ -875,8 +890,7 @@ namespace transport
 				else
 					session->SetTerminationTimeout (10); // most likely it's publishing, no follow-up messages expected, set timeout to 10 seconds
 				peer->sessions.push_back (session);
-				session->SendI2NPMessages (peer->delayedMessages);
+				session->SendI2NPMessages (peer->delayedMessages); // send and clear
-				peer->delayedMessages.clear ();
 			}
 			else // incoming connection or peer test
 			{
@@ -887,7 +901,10 @@ namespace transport
 					return;
 				}
 				if (!session->IsOutgoing ()) // incoming
-					session->SendI2NPMessages ({ CreateDatabaseStoreMsg () }); // send DatabaseStore
+				{
+					std::list<std::shared_ptr<I2NPMessage> > msgs{ CreateDatabaseStoreMsg () };
+					session->SendI2NPMessages (msgs); // send DatabaseStore
+				}	
 				auto r = i2p::data::netdb.FindRouter (ident); // router should be in netdb after SessionConfirmed
 				if (r) r->GetProfile ()->Connected ();
 				auto ts = i2p::util::GetSecondsSinceEpoch ();

libi2pd/Transports.h

@@ -71,7 +71,7 @@ namespace transport
 		std::shared_ptr<const i2p::data::RouterInfo> router;
 		std::list<std::shared_ptr<TransportSession> > sessions;
 		uint64_t creationTime, nextRouterInfoUpdateTime, lastSelectionTime;
-		std::vector<std::shared_ptr<i2p::I2NPMessage> > delayedMessages;
+		std::list<std::shared_ptr<i2p::I2NPMessage> > delayedMessages;
 		std::vector<i2p::data::RouterInfo::SupportedTransports> priority;
 		bool isHighBandwidth, isEligible;
 
@@ -141,7 +141,8 @@ namespace transport
 			void ReuseX25519KeysPair (std::shared_ptr<i2p::crypto::X25519Keys> pair);
 
 			void SendMessage (const i2p::data::IdentHash& ident, std::shared_ptr<i2p::I2NPMessage> msg);
-			void SendMessages (const i2p::data::IdentHash& ident, const std::vector<std::shared_ptr<i2p::I2NPMessage> >& msgs);
+			void SendMessages (const i2p::data::IdentHash& ident, std::list<std::shared_ptr<i2p::I2NPMessage> >& msgs);
+			void SendMessages (const i2p::data::IdentHash& ident, std::list<std::shared_ptr<i2p::I2NPMessage> >&& msgs);
 
 			void PeerConnected (std::shared_ptr<TransportSession> session);
 			void PeerDisconnected (std::shared_ptr<TransportSession> session);
@@ -185,7 +186,7 @@ namespace transport
 			void Run ();
 			void RequestComplete (std::shared_ptr<const i2p::data::RouterInfo> r, const i2p::data::IdentHash& ident);
 			void HandleRequestComplete (std::shared_ptr<const i2p::data::RouterInfo> r, i2p::data::IdentHash ident);
-			void PostMessages (i2p::data::IdentHash ident, std::vector<std::shared_ptr<i2p::I2NPMessage> > msgs);
+			void PostMessages (const i2p::data::IdentHash& ident, std::list<std::shared_ptr<i2p::I2NPMessage> >& msgs);
 			bool ConnectToPeer (const i2p::data::IdentHash& ident, std::shared_ptr<Peer> peer);
 			void SetPriority (std::shared_ptr<Peer> peer) const;
 			void HandlePeerCleanupTimer (const boost::system::error_code& ecode);

libi2pd/Tunnel.cpp

@@ -350,7 +350,8 @@ namespace tunnel
 
 	Tunnels::Tunnels (): m_IsRunning (false), m_Thread (nullptr), m_MaxNumTransitTunnels (DEFAULT_MAX_NUM_TRANSIT_TUNNELS),
 		m_TotalNumSuccesiveTunnelCreations (0), m_TotalNumFailedTunnelCreations (0), // for normal average
-		m_TunnelCreationSuccessRate (TCSR_START_VALUE), m_TunnelCreationAttemptsNum(0)
+		m_TunnelCreationSuccessRate (TCSR_START_VALUE), m_TunnelCreationAttemptsNum(0),
+		m_Rng(i2p::util::GetMonotonicMicroseconds ()%1000000LL)
 	{
 	}
 

libi2pd/Tunnel.h

@@ -18,6 +18,7 @@
 #include <thread>
 #include <mutex>
 #include <memory>
+#include <random>
 #include "util.h"
 #include "Queue.h"
 #include "Crypto.h"
@@ -244,6 +245,8 @@ namespace tunnel
 			uint32_t GetMaxNumTransitTunnels () const { return m_MaxNumTransitTunnels; };
 			int GetCongestionLevel() const { return m_MaxNumTransitTunnels ? CONGESTION_LEVEL_FULL * m_TransitTunnels.size() / m_MaxNumTransitTunnels : CONGESTION_LEVEL_FULL; }
 
+			std::mt19937& GetRng () { return m_Rng; };
+			
 		private:
 
 			template<class TTunnel>
@@ -307,6 +310,7 @@ namespace tunnel
 			int m_TotalNumSuccesiveTunnelCreations, m_TotalNumFailedTunnelCreations;
 			double m_TunnelCreationSuccessRate;
 			int m_TunnelCreationAttemptsNum;
+			std::mt19937 m_Rng;
 
 		public:
 

libi2pd/TunnelGateway.cpp

@@ -221,7 +221,7 @@ namespace tunnel
 	void TunnelGateway::SendBuffer ()
 	{
 		m_Buffer.CompleteCurrentTunnelDataMessage ();
-		std::vector<std::shared_ptr<I2NPMessage> > newTunnelMsgs;
+		std::list<std::shared_ptr<I2NPMessage> > newTunnelMsgs;
 		const auto& tunnelDataMsgs = m_Buffer.GetTunnelDataMsgs ();
 		for (auto& tunnelMsg : tunnelDataMsgs)
 		{
@@ -234,7 +234,7 @@ namespace tunnel
 			m_NumSentBytes += TUNNEL_DATA_MSG_SIZE;
 		}
 		m_Buffer.ClearTunnelDataMsgs ();
-		i2p::transport::transports.SendMessages (m_Tunnel->GetNextIdentHash (), newTunnelMsgs);
+		i2p::transport::transports.SendMessages (m_Tunnel->GetNextIdentHash (), std::move (newTunnelMsgs));
 	}
 }
 }

libi2pd_client/AddressBook.cpp

@@ -305,7 +305,7 @@ namespace client
 		identHash = hash;
 	}
 
-	AddressBook::AddressBook (): m_Storage(nullptr), m_IsLoaded (false), m_IsDownloading (false),
+	AddressBook::AddressBook (): m_Storage(nullptr), m_IsLoaded (false),
 		m_NumRetries (0), m_DefaultSubscription (nullptr), m_SubscriptionsUpdateTimer (nullptr),
 		m_IsEnabled (true)
 	{
@@ -344,20 +344,28 @@ namespace client
 			delete m_SubscriptionsUpdateTimer;
 			m_SubscriptionsUpdateTimer = nullptr;
 		}
-		if (m_IsDownloading)
+		bool isDownloading = m_Downloading.valid ();
+		if (isDownloading)
+		{
+			if (m_Downloading.wait_for(std::chrono::seconds(0)) == std::future_status::ready)
+				isDownloading = false;
+			else	
 			{	
 				LogPrint (eLogInfo, "Addressbook: Subscriptions are downloading, abort");
 				for (int i = 0; i < 30; i++)
 				{
-				if (!m_IsDownloading)
+					if (m_Downloading.wait_for(std::chrono::seconds(1)) == std::future_status::ready) // wait for 1 seconds
 					{
+						isDownloading = false;
 						LogPrint (eLogInfo, "Addressbook: Subscriptions download complete");
 						break;
 					}
-				std::this_thread::sleep_for (std::chrono::seconds (1)); // wait for 1 seconds
 				}
+			}	
+			if (!isDownloading)
+				m_Downloading.get ();
+			else
 				LogPrint (eLogError, "Addressbook: Subscription download timeout");
-			m_IsDownloading = false;
 		}
 		if (m_Storage)
 		{
@@ -582,16 +590,15 @@ namespace client
 			}
 			else
 			{
-				LogPrint (eLogInfo, "Addressbook: Loading subscriptions from config file");
+				LogPrint (eLogInfo, "Addressbook: Loading subscriptions from config");
 				// using config file items
 				std::string subscriptionURLs; i2p::config::GetOption("addressbook.subscriptions", subscriptionURLs);
 				std::vector<std::string> subsList;
 				boost::split(subsList, subscriptionURLs, boost::is_any_of(","), boost::token_compress_on);
 
 				for (const auto& s: subsList)
-				{
+					if (!s.empty ())
 						m_Subscriptions.push_back (std::make_shared<AddressBookSubscription> (*this, s));
-				}
 				LogPrint (eLogInfo, "Addressbook: ", m_Subscriptions.size (), " subscriptions urls loaded");
 			}
 		}
@@ -645,7 +652,6 @@ namespace client
 
 	void AddressBook::DownloadComplete (bool success, const i2p::data::IdentHash& subscription, const std::string& etag, const std::string& lastModified)
 	{
-		m_IsDownloading = false;
 		m_NumRetries++;
 		int nextUpdateTimeout = m_NumRetries*CONTINIOUS_SUBSCRIPTION_RETRY_TIMEOUT;
 		if (m_NumRetries > CONTINIOUS_SUBSCRIPTION_MAX_NUM_RETRIES || nextUpdateTimeout > CONTINIOUS_SUBSCRIPTION_UPDATE_TIMEOUT)
@@ -700,7 +706,13 @@ namespace client
 				LogPrint(eLogWarning, "Addressbook: Missing local destination, skip subscription update");
 				return;
 			}
-			if (!m_IsDownloading && dest->IsReady ())
+			bool isDownloading = m_Downloading.valid ();
+			if (isDownloading && m_Downloading.wait_for(std::chrono::seconds(0)) == std::future_status::ready) // still active?
+			{
+				m_Downloading.get ();
+				isDownloading = false;
+			}	
+			if (!isDownloading && dest->IsReady ())
 			{
 				if (!m_IsLoaded)
 				{
@@ -709,17 +721,15 @@ namespace client
 					std::string defaultSubURL; i2p::config::GetOption("addressbook.defaulturl", defaultSubURL);
 					if (!m_DefaultSubscription)
 						m_DefaultSubscription = std::make_shared<AddressBookSubscription>(*this, defaultSubURL);
-					m_IsDownloading = true;
+					m_Downloading = std::async (std::launch::async,
-					std::thread load_hosts(std::bind (&AddressBookSubscription::CheckUpdates, m_DefaultSubscription));
+						std::bind (&AddressBookSubscription::CheckUpdates, m_DefaultSubscription));
-					load_hosts.detach(); // TODO: use join
 				}
 				else if (!m_Subscriptions.empty ())
 				{
 					// pick random subscription
 					auto ind = rand () % m_Subscriptions.size();
-					m_IsDownloading = true;
+					m_Downloading = std::async (std::launch::async,
-					std::thread load_hosts(std::bind (&AddressBookSubscription::CheckUpdates, m_Subscriptions[ind]));
+						std::bind (&AddressBookSubscription::CheckUpdates, m_Subscriptions[ind]));
-					load_hosts.detach(); // TODO: use join
 				}
 			}
 			else
@@ -823,7 +833,7 @@ namespace client
 		}
 	}
 
-	AddressBookSubscription::AddressBookSubscription (AddressBook& book, const std::string& link):
+	AddressBookSubscription::AddressBookSubscription (AddressBook& book, std::string_view link):
 		m_Book (book), m_Link (link)
 	{
 	}

libi2pd_client/AddressBook.h

@@ -11,10 +11,12 @@
 
 #include <string.h>
 #include <string>
+#include <string_view>
 #include <map>
 #include <vector>
 #include <iostream>
 #include <mutex>
+#include <future>
 #include <memory>
 #include <boost/asio.hpp>
 #include "Base.h"
@@ -124,7 +126,8 @@ namespace client
 			std::mutex m_LookupsMutex;
 			std::map<uint32_t, std::string> m_Lookups; // nonce -> address
 			AddressBookStorage * m_Storage;
-			volatile bool m_IsLoaded, m_IsDownloading;
+			volatile bool m_IsLoaded;
+			std::future<void> m_Downloading;
 			int m_NumRetries;
 			std::vector<std::shared_ptr<AddressBookSubscription> > m_Subscriptions;
 			std::shared_ptr<AddressBookSubscription> m_DefaultSubscription; // in case if we don't know any addresses yet
@@ -136,7 +139,7 @@ namespace client
 	{
 		public:
 
-			AddressBookSubscription (AddressBook& book, const std::string& link);
+			AddressBookSubscription (AddressBook& book, std::string_view link);
 			void CheckUpdates ();
 
 		private:

libi2pd_client/UDPTunnel.cpp

@@ -203,7 +203,7 @@ namespace client
 		std::vector<std::shared_ptr<DatagramSessionInfo> > sessions;
 		std::lock_guard<std::mutex> lock (m_SessionsMutex);
 
-		for (auto it: m_Sessions)
+        for (const auto &it: m_Sessions)
 		{
 			auto s = it.second;
 			if (!s->m_Destination) continue;