Merge branch 'master' of https://github.com/orignal/i2pd

ElGamal.h

@@ -12,25 +12,47 @@ namespace i2p
 {
 namespace crypto
 {
-	inline void ElGamalEncrypt (const uint8_t * key, const uint8_t * data, int len, 
+
-		uint8_t * encrypted, bool zeroPadding = false) // 514 with padding and 512 without
+	class ElGamalEncryption
 	{
-		CryptoPP::AutoSeededRandomPool rnd;		
+		public:
-		CryptoPP::Integer y(key, 256), k(rnd, CryptoPP::Integer::One(), elgp-1);
+
-
+			ElGamalEncryption (const uint8_t * key):
-		if (zeroPadding)
+				y (key, 256), k (rnd, CryptoPP::Integer::One(), elgp-1),
-		{
+				a (a_exp_b_mod_c (elgg, k, elgp)), b1 (a_exp_b_mod_c (y, k, elgp))
-			encrypted[0] = 0;
+			{
-			encrypted[257] = 0;
+			}
-		}	
+
-		a_exp_b_mod_c (elgg, k, elgp).Encode (zeroPadding ? encrypted + 1 : encrypted, 256);
+			void Encrypt (const uint8_t * data, int len, uint8_t * encrypted, bool zeroPadding = false)
-		uint8_t m[255];
+			{
-		m[0] = 0xFF;
+				// calculate b = b1*m mod p
-		memcpy (m+33, data, len);
+				uint8_t m[255];
-		CryptoPP::SHA256().CalculateDigest(m+1, m+33, 222);
+				m[0] = 0xFF;
-		a_times_b_mod_c (a_exp_b_mod_c (y, k, elgp), 
+				memcpy (m+33, data, len);
-			CryptoPP::Integer (m, 255), elgp).Encode (zeroPadding ? encrypted + 258 : encrypted + 256, 256);
+				CryptoPP::SHA256().CalculateDigest(m+1, m+33, 222);
-	}	
+				CryptoPP::Integer b (a_times_b_mod_c (b1, CryptoPP::Integer (m, 255), elgp));
+
+				// copy a and b
+				if (zeroPadding)
+				{
+					encrypted[0] = 0;
+					a.Encode (encrypted + 1, 256);
+					encrypted[257] = 0;
+					b.Encode (encrypted + 258, 256);
+				}	
+				else
+				{
+					a.Encode (encrypted, 256);	
+					b.Encode (encrypted + 256, 256);
+				}	
+			}
+
+		private:
+
+			CryptoPP::AutoSeededRandomPool rnd;	
+			CryptoPP::Integer y, k, a, b1;	
+			bool m_ZeroPadding;	
+	};
 
 	inline bool ElGamalDecrypt (const uint8_t * key, const uint8_t * encrypted, 
 		uint8_t * data, bool zeroPadding = false)

Garlic.cpp

@@ -2,7 +2,6 @@
 #include "I2PEndian.h"
 #include <map>
 #include <string>
-#include "ElGamal.h"
 #include "RouterContext.h"
 #include "I2NPProtocol.h"
 #include "Tunnel.h"
@@ -14,7 +13,7 @@ namespace i2p
 {
 namespace garlic
 {	
-	GarlicRoutingSession::GarlicRoutingSession (const i2p::data::RoutingDestination * destination, int numTags):
+	GarlicRoutingSession::GarlicRoutingSession (const i2p::data::RoutingDestination& destination, int numTags):
 		m_Destination (destination), m_FirstMsgID (0), m_IsAcknowledged (false), 
 		m_NumTags (numTags), m_NextTag (-1), m_SessionTags (0)
 	{
@@ -56,7 +55,7 @@ namespace garlic
 			m_Rnd.GenerateBlock (elGamal.preIV, 32); // Pre-IV
 			uint8_t iv[32]; // IV is first 16 bytes
 			CryptoPP::SHA256().CalculateDigest(iv, elGamal.preIV, 32); 
-			i2p::crypto::ElGamalEncrypt (m_Destination->GetEncryptionPublicKey (), (uint8_t *)&elGamal, sizeof(elGamal), buf, true);			
+			m_Destination.GetElGamalEncryption ()->Encrypt ((uint8_t *)&elGamal, sizeof(elGamal), buf, true);			
 			m_Encryption.SetKeyWithIV (m_SessionKey, 32, iv);
 			buf += 514;
 			len += 514;	
@@ -140,7 +139,7 @@ namespace garlic
 		}	
 		if (msg) // clove message ifself if presented
 		{	
-			size += CreateGarlicClove (payload + size, msg, m_Destination->IsDestination ());
+			size += CreateGarlicClove (payload + size, msg, m_Destination.IsDestination ());
 			(*numCloves)++;
 		}	
 		
@@ -161,7 +160,7 @@ namespace garlic
 		{
 			buf[size] = eGarlicDeliveryTypeDestination << 5;//  delivery instructions flag destination
 			size++;
-			memcpy (buf + size, m_Destination->GetIdentHash (), 32);
+			memcpy (buf + size, m_Destination.GetIdentHash (), 32);
 			size += 32;
 		}	
 		else	
@@ -230,33 +229,31 @@ namespace garlic
 		m_Sessions.clear ();
 	}	
 
-	I2NPMessage * GarlicRouting::WrapSingleMessage (const i2p::data::RoutingDestination * destination, I2NPMessage * msg)
+	I2NPMessage * GarlicRouting::WrapSingleMessage (const i2p::data::RoutingDestination& destination, I2NPMessage * msg)
 	{
-		if (!destination) return nullptr;
+		auto it = m_Sessions.find (destination.GetIdentHash ());
-		auto it = m_Sessions.find (destination->GetIdentHash ());
 		if (it != m_Sessions.end ())
 		{
 			delete it->second;
 			m_Sessions.erase (it);
 		}
 		GarlicRoutingSession * session = new GarlicRoutingSession (destination, 0); // not follow-on messages expected
-		m_Sessions[destination->GetIdentHash ()] = session;
+		m_Sessions[destination.GetIdentHash ()] = session;
 
 		return session->WrapSingleMessage (msg, nullptr);
 	}	
 
-	I2NPMessage * GarlicRouting::WrapMessage (const i2p::data::RoutingDestination * destination, 
+	I2NPMessage * GarlicRouting::WrapMessage (const i2p::data::RoutingDestination& destination, 
 		I2NPMessage * msg, I2NPMessage * leaseSet)
 	{
-		if (!destination) return nullptr;
+		auto it = m_Sessions.find (destination.GetIdentHash ());
-		auto it = m_Sessions.find (destination->GetIdentHash ());
 		GarlicRoutingSession * session = nullptr;
 		if (it != m_Sessions.end ())
 			session = it->second;
 		if (!session)
 		{
 			session = new GarlicRoutingSession (destination, 4); // TODO: change it later
-			m_Sessions[destination->GetIdentHash ()] = session;
+			m_Sessions[destination.GetIdentHash ()] = session;
 		}	
 
 		I2NPMessage * ret = session->WrapSingleMessage (msg, leaseSet);

Garlic.h

@@ -37,7 +37,7 @@ namespace garlic
 	{
 		public:
 
-			GarlicRoutingSession (const i2p::data::RoutingDestination * destination, int numTags);
+			GarlicRoutingSession (const i2p::data::RoutingDestination& destination, int numTags);
 			~GarlicRoutingSession ();
 			I2NPMessage * WrapSingleMessage (I2NPMessage * msg, I2NPMessage * leaseSet);
 			int GetNextTag () const { return m_NextTag; };
@@ -57,7 +57,7 @@ namespace garlic
 
 		private:
 
-			const i2p::data::RoutingDestination * m_Destination;
+			const i2p::data::RoutingDestination& m_Destination;
 			uint8_t m_SessionKey[32];
 			uint32_t m_FirstMsgID; // first message ID
 			bool m_IsAcknowledged;
@@ -78,8 +78,8 @@ namespace garlic
 			void HandleGarlicMessage (uint8_t * buf, size_t len, bool isFromTunnel);
 			void HandleDeliveryStatusMessage (uint8_t * buf, size_t len);
 			
-			I2NPMessage * WrapSingleMessage (const i2p::data::RoutingDestination * destination, I2NPMessage * msg);
+			I2NPMessage * WrapSingleMessage (const i2p::data::RoutingDestination& destination, I2NPMessage * msg);
-			I2NPMessage * WrapMessage (const i2p::data::RoutingDestination * destination, 
+			I2NPMessage * WrapMessage (const i2p::data::RoutingDestination& destination, 
 			    I2NPMessage * msg, I2NPMessage * leaseSet = nullptr);
 
 		private:

HTTPServer.cpp

@@ -60,9 +60,20 @@ namespace util
   		{
 			m_Buffer[bytes_transferred] = 0;
 			auto address = ExtractAddress ();
-			LogPrint (address);
 			if (address.length () > 1) // not just '/'
-				HandleDestinationRequest (address.substr (1)); // exclude '/'
+			{
+				std::string uri ("/"), b32;
+				size_t pos = address.find ('/', 1);
+				if (pos == std::string::npos)
+					b32 = address.substr (1); // excluding leading '/' to end of line
+				else
+				{
+					b32 = address.substr (1, pos - 1); // excluding leading '/' to next '/'
+					uri = address.substr (pos); // rest of line
+				}	
+
+				HandleDestinationRequest (b32, uri); 
+			}	
 			else	  
 				HandleRequest ();
 			boost::asio::async_write (*m_Socket, m_Reply.to_buffers(),
@@ -149,14 +160,18 @@ namespace util
 		s << "<p><a href=\"zmw2cyw2vj7f6obx3msmdvdepdhnw2ctc4okza2zjxlukkdfckhq\">Flibusta</a></p>";
 	}	
 
-	void HTTPConnection::HandleDestinationRequest (std::string b32)
+	void HTTPConnection::HandleDestinationRequest (const std::string& b32, const std::string& uri)
 	{
 		uint8_t destination[32];
-		i2p::data::Base32ToByteStream (b32.c_str (), b32.length (), destination, 32);
+		if (i2p::data::Base32ToByteStream (b32.c_str (), b32.length (), destination, 32) != 32)
+		{
+			LogPrint ("Invalid Base32 address ", b32);
+			return;
+		}	
 		auto leaseSet = i2p::data::netdb.FindLeaseSet (destination);
 		if (!leaseSet || !leaseSet->HasNonExpiredLeases ())
 		{
-			i2p::data::netdb.RequestDestination (i2p::data::IdentHash (destination), true);
+			i2p::data::netdb.Subscribe(destination);
 			std::this_thread::sleep_for (std::chrono::seconds(10)); // wait for 10 seconds
 			leaseSet = i2p::data::netdb.FindLeaseSet (destination);
 			if (!leaseSet || !leaseSet->HasNonExpiredLeases ()) // still no LeaseSet
@@ -170,17 +185,10 @@ namespace util
 				return;
 			}	
 		}	
-		// we found LeaseSet
+		auto s = i2p::stream::CreateStream (*leaseSet);
-		if (leaseSet->HasExpiredLeases ())
-		{
-			// we should re-request LeaseSet
-			LogPrint ("LeaseSet re-requested");
-			i2p::data::netdb.RequestDestination (i2p::data::IdentHash (destination), true);
-		}	
-		auto s = i2p::stream::CreateStream (leaseSet);
 		if (s)
 		{
-			std::string request = "GET / HTTP/1.1\n Host:" + b32 + ".b32.i2p\n";
+			std::string request = "GET " + uri + " HTTP/1.1\n Host:" + b32 + ".b32.i2p\n";
 			s->Send ((uint8_t *)request.c_str (), request.length (), 10);			
 			std::stringstream ss;
 			uint8_t buf[8192];
@@ -200,7 +208,7 @@ namespace util
 			else // nothing received
 				ss << "<html>Not responding</html>";
 			s->Close ();
-			//DeleteStream (s);
+			DeleteStream (s);
 			
 			m_Reply.content = ss.str ();
 			m_Reply.headers.resize(2);

HTTPServer.h

@@ -48,7 +48,7 @@ namespace util
 			void HandleWrite(const boost::system::error_code& ecode);
 
 			void HandleRequest ();
-			void HandleDestinationRequest (std::string b32);
+			void HandleDestinationRequest (const std::string& b32, const std::string& uri);
 			void FillContent (std::stringstream& s);
 			std::string ExtractAddress ();
 			

I2NPProtocol.cpp

@@ -212,7 +212,7 @@ namespace i2p
 		const I2NPBuildRequestRecordClearText& clearText,
 	    I2NPBuildRequestRecordElGamalEncrypted& record)
 	{
-		i2p::crypto::ElGamalEncrypt (router.GetRouterIdentity ().publicKey, (uint8_t *)&clearText, sizeof(clearText), record.encrypted);
+		router.GetElGamalEncryption ()->Encrypt ((uint8_t *)&clearText, sizeof(clearText), record.encrypted);
 		memcpy (record.toPeer, (const uint8_t *)router.GetIdentHash (), 16);
 	}	
 	
@@ -392,7 +392,7 @@ namespace i2p
 		LogPrint ("TunnelGateway of ", (int)len, " bytes for tunnel ", (unsigned int)tunnelID, ". Msg type ", (int)msg->GetHeader()->typeID);
 		i2p::tunnel::TransitTunnel * tunnel =  i2p::tunnel::tunnels.GetTransitTunnel (tunnelID);
 		if (tunnel)
-			tunnel->SendTunnelDataMsg (nullptr, 0, msg);
+			tunnel->SendTunnelDataMsg (msg);
 		else
 		{	
 			LogPrint ("Tunnel ", (unsigned int)tunnelID, " not found");

Identity.h

@@ -3,6 +3,7 @@
 
 #include <inttypes.h>
 #include <string.h>
+#include "ElGamal.h"
 
 namespace i2p
 {
@@ -84,9 +85,24 @@ namespace data
 	class RoutingDestination
 	{
 		public:
+
+			RoutingDestination (): m_ElGamalEncryption (nullptr) {};
+			virtual ~RoutingDestination () { delete m_ElGamalEncryption; };
+			
 			virtual const IdentHash& GetIdentHash () const = 0;
 			virtual const uint8_t * GetEncryptionPublicKey () const = 0;
 			virtual bool IsDestination () const = 0; // for garlic 
+
+			i2p::crypto::ElGamalEncryption * GetElGamalEncryption () const
+			{
+				if (!m_ElGamalEncryption)
+					m_ElGamalEncryption = new i2p::crypto::ElGamalEncryption (GetEncryptionPublicKey ());
+				return m_ElGamalEncryption;
+			}
+			
+		private:
+
+			mutable i2p::crypto::ElGamalEncryption * m_ElGamalEncryption; // use lazy initialization
 	};	
 }
 }

NTCPSession.h

@@ -60,7 +60,7 @@ namespace ntcp
 	
 #pragma pack()	
 
-	const int TERMINATION_TIMEOUT = 60; // 1 minute
+	const int TERMINATION_TIMEOUT = 120; // 2 minutes
 	class NTCPSession
 	{
 		public:

NetDb.cpp

@@ -25,7 +25,7 @@ namespace data
 		I2NPMessage * msg = i2p::CreateDatabaseLookupMsg (m_Destination, 
 			replyTunnel->GetNextIdentHash (), replyTunnel->GetNextTunnelID (), m_IsExploratory, &m_ExcludedPeers);
 		if (m_IsLeaseSet) // wrap lookup message into garlic
-			msg = i2p::garlic::routing.WrapSingleMessage (router, msg);
+			msg = i2p::garlic::routing.WrapSingleMessage (*router, msg);
 		m_ExcludedPeers.insert (router->GetIdentHash ());
 		m_LastRouter = router;
 		m_LastReplyTunnel = replyTunnel;
@@ -90,7 +90,7 @@ namespace data
 	
 	void NetDb::Run ()
 	{
-		uint32_t lastTs = 0;
+		uint32_t lastSave = 0, lastPublish = 0;
 		m_IsRunning = true;
 		while (m_IsRunning)
 		{	
@@ -120,11 +120,19 @@ namespace data
 					Explore ();
 
 				uint64_t ts = i2p::util::GetSecondsSinceEpoch ();
-				if (ts - lastTs >= 60) // save routers every minute
+				if (ts - lastSave >= 60) // save routers and validate subscriptions every minute
 				{
-					if (lastTs)
+					if (lastSave)
+					{
 						SaveUpdated (m_NetDbPath);
-					lastTs = ts;
+						ValidateSubscriptions ();
+					}	
+					lastSave = ts;
+				}	
+				if (ts - lastPublish >= 600) // publish every 10 minutes
+				{
+					Publish ();
+					lastPublish = ts;
 				}	
 			}
 			catch (std::exception& ex)
@@ -486,7 +494,10 @@ namespace data
 						else // we should send directly
 						{
 							if (!dest->IsLeaseSet ()) // if not LeaseSet
-								i2p::transports.SendMessage (router, dest->CreateRequestMessage (router));
+							{
+								if (!dest->IsExcluded (router) && dest->GetNumExcludedPeers () < 30) 
+									i2p::transports.SendMessage (router, dest->CreateRequestMessage (router));
+							}	
 							else
 								LogPrint ("Can't request LeaseSet");
 						}	
@@ -543,6 +554,17 @@ namespace data
 		}
 	}	
 
+	void NetDb::Publish ()
+	{
+		std::set<IdentHash> excluded; // TODO: fill up later
+		auto floodfill = GetClosestFloodfill (i2p::context.GetRouterInfo ().GetIdentHash (), excluded);
+		if (floodfill)
+		{
+			LogPrint ("Publishing our RouterInfo to ", floodfill->GetIdentHashAbbreviation ());
+			transports.SendMessage (floodfill->GetIdentHash (), CreateDatabaseStoreMsg ());	
+		}	
+	}	
+	
 	RequestedDestination * NetDb::CreateRequestedDestination (const IdentHash& dest,
 		bool isLeaseSet, bool isExploratory)
 	{
@@ -644,5 +666,33 @@ namespace data
 		return r;
 	}	
 
+	void NetDb::Subscribe (const IdentHash& ident)
+	{
+		LeaseSet * leaseSet = FindLeaseSet (ident);
+		if (!leaseSet)
+		{
+			LogPrint ("LeaseSet requested");	
+			RequestDestination (ident, true);
+		}
+		m_Subscriptions.insert (ident);
+	}
+		
+	void NetDb::Unsubscribe (const IdentHash& ident)
+	{
+		m_Subscriptions.erase (ident);
+	}
+
+	void NetDb::ValidateSubscriptions ()
+	{
+		for (auto it : m_Subscriptions)
+		{
+			LeaseSet * leaseSet = FindLeaseSet (it);
+			if (!leaseSet || leaseSet->HasExpiredLeases ())
+			{
+				LogPrint ("LeaseSet re-requested");	
+				RequestDestination (it, true);
+			}			
+		}
+	}
 }
 }

NetDb.h

@@ -63,7 +63,9 @@ namespace data
 			void AddLeaseSet (uint8_t * buf, int len);
 			RouterInfo * FindRouter (const IdentHash& ident) const;
 			LeaseSet * FindLeaseSet (const IdentHash& destination) const;
-			
+			void Subscribe (const IdentHash& ident); // keep LeaseSets upto date			
+			void Unsubscribe (const IdentHash& ident);	
+
 			void RequestDestination (const char * b32); // in base32
 			void RequestDestination (const IdentHash& destination, bool isLeaseSet = false);
 						
@@ -82,6 +84,8 @@ namespace data
 			void SaveUpdated (const char * directory);
 			void Run (); // exploratory thread
 			void Explore ();
+			void Publish ();
+			void ValidateSubscriptions ();
 			const RouterInfo * GetClosestFloodfill (const IdentHash& destination, const std::set<IdentHash>& excluded) const;
 
 			RequestedDestination * CreateRequestedDestination (const IdentHash& dest, 
@@ -94,6 +98,7 @@ namespace data
 			std::map<IdentHash, LeaseSet *> m_LeaseSets;
 			std::map<IdentHash, RouterInfo *> m_RouterInfos;
 			std::map<IdentHash, RequestedDestination *> m_RequestedDestinations;
+			std::set<IdentHash> m_Subscriptions;
 			
 			bool m_IsRunning;
 			int m_ReseedRetries;

RouterInfo.cpp

@@ -129,6 +129,27 @@ namespace data
 					address.port = boost::lexical_cast<int>(value);
 				else if (!strcmp (key, "key"))
 					Base64ToByteStream (value, strlen (value), address.key, 32);
+				else if (key[0] == 'i')
+				{	
+					// introducers
+					size_t l = strlen(key); 	
+					unsigned char index = key[l-1]; // TODO:
+					key[l-1] = 0;
+					if (index >= address.introducers.size ())
+						address.introducers.resize (index + 1); 
+					Introducer& introducer = address.introducers.at (index);
+					if (!strcmp (key, "ihost"))
+					{
+						boost::system::error_code ecode;
+						introducer.iHost = boost::asio::ip::address::from_string (value, ecode);
+					}	
+					else if (!strcmp (key, "iport"))
+						introducer.iPort = boost::lexical_cast<int>(value);
+					else if (!strcmp (key, "itag"))
+						introducer.iTag = boost::lexical_cast<uint32_t>(value);
+					else if (!strcmp (key, "ikey"))
+						Base64ToByteStream (value, strlen (value), introducer.iKey, 32);
+				}
 			}	
 			m_Addresses.push_back(address);
 		}	
@@ -302,6 +323,13 @@ namespace data
 		else
 			return m_SupportedTransports & (eSSUV4 | eSSUV6);
 	}
+
+	bool RouterInfo::UsesIntroducer () const
+	{
+		if (!IsSSU ()) return false;
+		auto address = GetSSUAddress (true); // no introducers for v6
+		return address && !address->introducers.empty ();
+	}		
 		
 	const RouterInfo::Address * RouterInfo::GetNTCPAddress (bool v4only) const
 	{

RouterInfo.h

@@ -32,6 +32,14 @@ namespace data
 				eTransportSSU
 			};
 
+			struct Introducer			
+			{
+				boost::asio::ip::address iHost;
+				int iPort;
+				uint8_t iKey[32];
+				uint32_t iTag;
+			};
+
 			struct Address
 			{
 				TransportStyle transportStyle;
@@ -39,7 +47,9 @@ namespace data
 				int port;
 				uint64_t date;
 				uint8_t cost;
-				uint8_t key[32]; // into key for SSU
+				// SSU only
+				uint8_t key[32]; // intro key for SSU
+				std::vector<Introducer> introducers;
 			};
 			
 			RouterInfo (const char * filename);
@@ -65,6 +75,7 @@ namespace data
 			bool IsNTCP (bool v4only = true) const;
 			bool IsSSU (bool v4only = true) const;
 			bool IsCompatible (const RouterInfo& other) const { return m_SupportedTransports & other.m_SupportedTransports; };
+			bool UsesIntroducer () const;
 			
 			void SetUnreachable (bool unreachable) { m_IsUnreachable = unreachable; }; 
 			bool IsUnreachable () const { return m_IsUnreachable; };

SSU.cpp

@@ -65,6 +65,15 @@ namespace ssu
 				// session confirmed
 				ProcessSessionConfirmed (buf, len);
 			break;
+			case eSessionRelayRequestSent:
+				// relay response
+				ProcessRelayResponse (buf,len);
+			break;
+			case eSessionRelayRequestReceived:
+				// HolePunch
+				m_State = eSessionStateUnknown;
+				Connect ();
+			break;
 			default:
 				LogPrint ("SSU state not implemented yet");
 		}
@@ -91,8 +100,12 @@ namespace ssu
 					LogPrint ("SSU session destroy received");
 					if (m_Server)
 						m_Server->DeleteSession (this); // delete this 
-				}
+					break;
-				break;	
+				}	
+				case PAYLOAD_TYPE_RELAY_INTRO:
+					LogPrint ("SSU relay intro received");
+					// TODO:
+				break;
 				default:
 					LogPrint ("Unexpected SSU payload type ", (int)payloadType);
 			}
@@ -197,6 +210,37 @@ namespace ssu
 		m_Server->Send (buf, 304, m_RemoteEndpoint);
 	}
 
+	void SSUSession::SendRelayRequest (const i2p::data::RouterInfo::Introducer& introducer)
+	{
+		auto address = i2p::context.GetRouterInfo ().GetSSUAddress ();
+		if (!address)
+		{
+			LogPrint ("SSU is not supported");
+			return;
+		}
+	
+		uint8_t buf[96 + 18]; 
+		uint8_t * payload = buf + sizeof (SSUHeader);
+		*(uint32_t *)payload = htobe32 (introducer.iTag);
+		payload += 4;
+		*payload = 0; // no address
+		payload++;
+		*(uint16_t *)payload = 0; // port = 0
+		payload += 2;
+		*payload = 0; // challenge
+		payload++;	
+		memcpy (payload, address->key, 32);
+		payload += 32;
+		CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
+		*(uint32_t *)payload = htobe32 (rnd.GenerateWord32 ()); // nonce	
+
+		uint8_t iv[16];
+		rnd.GenerateBlock (iv, 16); // random iv
+		FillHeaderAndEncrypt (PAYLOAD_TYPE_RELAY_REQUEST, buf, 96, introducer.iKey, iv, introducer.iKey);
+		m_State = eSessionRelayRequestSent;		
+		m_Server->Send (buf, 96, m_RemoteEndpoint);
+	}
+
 	void SSUSession::SendSessionCreated (const uint8_t * x)
 	{
 		auto introKey = GetIntroKey ();
@@ -282,6 +326,46 @@ namespace ssu
 		m_Server->Send (buf, 480, m_RemoteEndpoint);
 	}
 
+	void SSUSession::ProcessRelayResponse (uint8_t * buf, size_t len)
+	{
+		LogPrint ("Process relay response");
+		auto address = i2p::context.GetRouterInfo ().GetSSUAddress ();
+		if (!address)
+		{
+			LogPrint ("SSU is not supported");
+			return;
+		}
+
+		if (Validate (buf, len, address->key))
+		{
+			Decrypt (buf, len, address->key);
+			SSUHeader * header = (SSUHeader *)buf;
+			if ((header->flag >> 4) == PAYLOAD_TYPE_RELAY_RESPONSE)
+			{
+				LogPrint ("Relay response received");		
+				m_State = eSessionRelayRequestReceived;
+				uint8_t * payload = buf + sizeof (SSUHeader);
+				payload++;
+				boost::asio::ip::address_v4 remoteIP (be32toh (*(uint32_t* )(payload)));
+				payload += 4;
+				uint16_t remotePort = be16toh (*(uint16_t *)(payload));
+				payload += 2;
+				boost::asio::ip::udp::endpoint newRemoteEndpoint(remoteIP, remotePort);
+				m_Server->ReassignSession (m_RemoteEndpoint, newRemoteEndpoint);
+				m_RemoteEndpoint = newRemoteEndpoint;	
+				payload++;
+				boost::asio::ip::address_v4 ourIP (be32toh (*(uint32_t* )(payload)));
+				payload += 4;
+				uint16_t ourPort = be16toh (*(uint16_t *)(payload));
+				payload += 2;
+				LogPrint ("Our external address is ", ourIP.to_string (), ":", ourPort);
+				i2p::context.UpdateAddress (ourIP.to_string ().c_str ());
+			}
+			else
+				LogPrint ("Unexpected payload type ", (int)(header->flag >> 4));
+		}
+	}
+
 	bool SSUSession::ProcessIntroKeyEncryptedMessage (uint8_t expectedPayloadType, uint8_t * buf, size_t len)
 	{
 		auto introKey = GetIntroKey ();
@@ -301,7 +385,7 @@ namespace ssu
 					LogPrint ("Unexpected payload type ", (int)(header->flag >> 4));	
 			}
 			else
-				LogPrint ("MAC verifcation failed");	
+				LogPrint ("MAC verification failed");	
 		}
 		else
 			LogPrint ("SSU is not supported");
@@ -368,6 +452,11 @@ namespace ssu
 		SendSessionRequest ();
 	}
 
+	void SSUSession::ConnectThroughIntroducer (const i2p::data::RouterInfo::Introducer& introducer)
+	{	
+		SendRelayRequest (introducer);
+	}
+
 	void SSUSession::Close ()
 	{
 		SendSesionDestroyed ();
@@ -677,12 +766,27 @@ namespace ssu
 					session = it->second;
 				else
 				{
-					// otherwise create new session
+					// otherwise create new session					
-					session = new SSUSession (this, remoteEndpoint, router);
+					if (!router->UsesIntroducer ())
-					m_Sessions[remoteEndpoint] = session;
+					{
-					LogPrint ("New SSU session to [", router->GetIdentHashAbbreviation (), "] ",
+						// connect directly
-						remoteEndpoint.address ().to_string (), ":", remoteEndpoint.port (), " created");
+						session = new SSUSession (this, remoteEndpoint, router);
-					session->Connect ();
+						m_Sessions[remoteEndpoint] = session;
+						LogPrint ("New SSU session to [", router->GetIdentHashAbbreviation (), "] ",
+							remoteEndpoint.address ().to_string (), ":", remoteEndpoint.port (), " created");
+						session->Connect ();
+					}
+					else
+					{
+						// connect to introducer
+						auto& introducer = address->introducers[0]; // TODO:
+						boost::asio::ip::udp::endpoint introducerEndpoint (introducer.iHost, introducer.iPort);
+						session = new SSUSession (this, introducerEndpoint, router);
+						m_Sessions[introducerEndpoint] = session;
+						LogPrint ("New SSU session to [", router->GetIdentHashAbbreviation (), 
+							"] created through introducer ", introducerEndpoint.address ().to_string (), ":", introducerEndpoint.port ());
+						session->ConnectThroughIntroducer (introducer);
+					}
 				}
 			}
 			else
@@ -709,6 +813,18 @@ namespace ssu
 			delete it.second;			
 		}	
 		m_Sessions.clear ();
+	}
+
+	void SSUServer::ReassignSession (const boost::asio::ip::udp::endpoint& oldEndpoint, const boost::asio::ip::udp::endpoint& newEndpoint)
+	{
+		auto it = m_Sessions.find (oldEndpoint);
+		if (it != m_Sessions.end ())
+		{
+			m_Sessions.erase (it);
+			m_Sessions[newEndpoint] = it->second;
+			LogPrint ("SSU session ressigned from ", oldEndpoint.address ().to_string (), ":", oldEndpoint.port (), 
+				" to ", newEndpoint.address ().to_string (), ":", newEndpoint.port ());
+		}						
 	}	
 }
 }

SSU.h

@@ -55,6 +55,8 @@ namespace ssu
 		eSessionStateCreatedReceived,
 		eSessionStateConfirmedSent,
 		eSessionStateConfirmedReceived,
+		eSessionRelayRequestSent,
+		eSessionRelayRequestReceived,	
 		eSessionStateEstablished
 	};		
 
@@ -68,6 +70,7 @@ namespace ssu
 			void ProcessNextMessage (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint);		
 
 			void Connect ();
+			void ConnectThroughIntroducer (const i2p::data::RouterInfo::Introducer& introducer);	
 			void Close ();
 			boost::asio::ip::udp::endpoint& GetRemoteEndpoint () { return m_RemoteEndpoint; };
 			void SendI2NPMessage (I2NPMessage * msg);
@@ -79,10 +82,12 @@ namespace ssu
 			void ProcessMessage (uint8_t * buf, size_t len); // call for established session
 			void ProcessSessionRequest (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint);
 			void SendSessionRequest ();
+			void SendRelayRequest (const i2p::data::RouterInfo::Introducer& introducer);
 			void ProcessSessionCreated (uint8_t * buf, size_t len);
 			void SendSessionCreated (const uint8_t * x);
 			void ProcessSessionConfirmed (uint8_t * buf, size_t len);
 			void SendSessionConfirmed (const uint8_t * y, const uint8_t * ourAddress, uint32_t relayTag);
+			void ProcessRelayResponse (uint8_t * buf, size_t len);
 			void Established ();
 			void ProcessData (uint8_t * buf, size_t len);	
 			void SendMsgAck (uint32_t msgID);
@@ -118,10 +123,11 @@ namespace ssu
 			void Stop ();
 			SSUSession * GetSession (const i2p::data::RouterInfo * router);
 			void DeleteSession (SSUSession * session);
-			void DeleteAllSessions ();
+			void DeleteAllSessions ();			
-			
+
 			const boost::asio::ip::udp::endpoint& GetEndpoint () const { return m_Endpoint; };			
 			void Send (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& to);
+			void ReassignSession (const boost::asio::ip::udp::endpoint& oldEndpoint, const boost::asio::ip::udp::endpoint& newEndpoint);	
 
 		private:
 

Streaming.cpp

@@ -14,7 +14,7 @@ namespace i2p
 {
 namespace stream
 {
-	Stream::Stream (StreamingDestination * local, const i2p::data::LeaseSet * remote):
+	Stream::Stream (StreamingDestination * local, const i2p::data::LeaseSet& remote):
 		m_SendStreamID (0), m_SequenceNumber (0), m_LastReceivedSequenceNumber (0), m_IsOpen (false),
 		m_LocalDestination (local), m_RemoteLeaseSet (remote), m_OutboundTunnel (nullptr)
 	{
@@ -172,7 +172,7 @@ namespace stream
 
 		if (!m_OutboundTunnel)
 			m_OutboundTunnel = i2p::tunnel::tunnels.GetNextOutboundTunnel ();
-		auto leases = m_RemoteLeaseSet->GetNonExpiredLeases ();
+		auto leases = m_RemoteLeaseSet.GetNonExpiredLeases ();
 		if (m_OutboundTunnel && !leases.empty ())
 		{
 			auto& lease = *leases.begin (); // TODO:
@@ -206,7 +206,7 @@ namespace stream
 			CreateDataMessage (this, packet, size));
 		if (m_OutboundTunnel)
 		{
-			auto leases = m_RemoteLeaseSet->GetNonExpiredLeases ();
+			auto leases = m_RemoteLeaseSet.GetNonExpiredLeases ();
 			if (!leases.empty ())
 			{	
 				auto& lease = *leases.begin (); // TODO:
@@ -252,7 +252,7 @@ namespace stream
 
 			I2NPMessage * msg = i2p::garlic::routing.WrapSingleMessage (m_RemoteLeaseSet, 
 				CreateDataMessage (this, packet, size));
-			auto leases = m_RemoteLeaseSet->GetNonExpiredLeases ();
+			auto leases = m_RemoteLeaseSet.GetNonExpiredLeases ();
 			if (m_OutboundTunnel && !leases.empty ())
 			{
 				auto& lease = *leases.begin (); // TODO:
@@ -318,7 +318,7 @@ namespace stream
 		
 	void StreamingDestination::HandleNextPacket (Packet * packet)
 	{
-		uint32_t sendStreamID = be32toh (*(uint32_t *)(packet->buf));
+		uint32_t sendStreamID = packet->GetSendStreamID ();
 		auto it = m_Streams.find (sendStreamID);
 		if (it != m_Streams.end ())
 			it->second->HandleNextPacket (packet);
@@ -329,7 +329,7 @@ namespace stream
 		}	
 	}	
 
-	Stream * StreamingDestination::CreateNewStream (const i2p::data::LeaseSet * remote)
+	Stream * StreamingDestination::CreateNewStream (const i2p::data::LeaseSet& remote)
 	{
 		Stream * s = new Stream (this, remote);
 		m_Streams[s->GetRecvStreamID ()] = s;
@@ -399,7 +399,7 @@ namespace stream
 		signer.SignMessage (i2p::context.GetRandomNumberGenerator (), buf, len, signature);
 	}
 		
-	Stream * CreateStream (const i2p::data::LeaseSet * remote)
+	Stream * CreateStream (const i2p::data::LeaseSet& remote)
 	{
 		if (!sharedLocalDestination)
 			sharedLocalDestination = new StreamingDestination ();

Streaming.h

@@ -65,11 +65,11 @@ namespace stream
 	{	
 		public:
 
-			Stream (StreamingDestination * local, const i2p::data::LeaseSet * remote);
+			Stream (StreamingDestination * local, const i2p::data::LeaseSet& remote);
 			~Stream ();
 			uint32_t GetSendStreamID () const { return m_SendStreamID; };
 			uint32_t GetRecvStreamID () const { return m_RecvStreamID; };
-			const i2p::data::LeaseSet * GetRemoteLeaseSet () const { return m_RemoteLeaseSet; };
+			const i2p::data::LeaseSet& GetRemoteLeaseSet () const { return m_RemoteLeaseSet; };
 			bool IsOpen () const { return m_IsOpen; };
 			bool IsEstablished () const { return m_SendStreamID; };
 			
@@ -91,7 +91,7 @@ namespace stream
 			uint32_t m_SendStreamID, m_RecvStreamID, m_SequenceNumber, m_LastReceivedSequenceNumber;
 			bool m_IsOpen;
 			StreamingDestination * m_LocalDestination;
-			const i2p::data::LeaseSet * m_RemoteLeaseSet;
+			const i2p::data::LeaseSet& m_RemoteLeaseSet;
 			i2p::util::Queue<Packet> m_ReceiveQueue;
 			std::set<Packet *, PacketCmp> m_SavedPackets;
 			i2p::tunnel::OutboundTunnel * m_OutboundTunnel;
@@ -109,7 +109,7 @@ namespace stream
 			I2NPMessage * GetLeaseSet ();
 			void Sign (uint8_t * buf, int len, uint8_t * signature) const;
 			
-			Stream * CreateNewStream (const i2p::data::LeaseSet * remote);
+			Stream * CreateNewStream (const i2p::data::LeaseSet& remote);
 			void DeleteStream (Stream * stream);
 			void HandleNextPacket (Packet * packet);
 
@@ -129,7 +129,7 @@ namespace stream
 			CryptoPP::DSA::PrivateKey m_SigningPrivateKey;
 	};	
 
-	Stream * CreateStream (const i2p::data::LeaseSet * remote);
+	Stream * CreateStream (const i2p::data::LeaseSet& remote);
 	void DeleteStream (Stream * stream);
 	
 	// assuming data is I2CP message

TransitTunnel.cpp

@@ -47,15 +47,18 @@ namespace tunnel
 		m_NumTransmittedBytes += tunnelMsg->GetLength ();
 	}
 
-	void TransitTunnel::SendTunnelDataMsg (const uint8_t * gwHash, uint32_t gwTunnel, i2p::I2NPMessage * msg)
+	void TransitTunnel::SendTunnelDataMsg (i2p::I2NPMessage * msg)
 	{	
 		LogPrint ("We are not a gateway for transit tunnel ", m_TunnelID);
 		i2p::DeleteI2NPMessage (msg);	
 	}		
 
-	void TransitTunnelGateway::SendTunnelDataMsg (const uint8_t * gwHash, uint32_t gwTunnel, i2p::I2NPMessage * msg)
+	void TransitTunnelGateway::SendTunnelDataMsg (i2p::I2NPMessage * msg)
 	{
-		m_Gateway.SendTunnelDataMsg (gwHash, gwTunnel, msg);
+		TunnelMessageBlock block;
+		block.deliveryType = eDeliveryTypeLocal;
+		block.data = msg;
+		m_Gateway.SendTunnelDataMsg (block);
 	}		
 
 	void TransitTunnelEndpoint::HandleTunnelDataMsg (i2p::I2NPMessage * tunnelMsg)

TransitTunnel.h

@@ -22,7 +22,7 @@ namespace tunnel
 	    		const uint8_t * layerKey,const uint8_t * ivKey); 
 			
 			virtual void HandleTunnelDataMsg (i2p::I2NPMessage * tunnelMsg);
-			virtual void SendTunnelDataMsg (const uint8_t * gwHash, uint32_t gwTunnel, i2p::I2NPMessage * msg);
+			virtual void SendTunnelDataMsg (i2p::I2NPMessage * msg);
 			virtual size_t GetNumTransmittedBytes () const { return m_NumTransmittedBytes; };
 			
 			uint32_t GetTunnelID () const { return m_TunnelID; };
@@ -54,7 +54,7 @@ namespace tunnel
 				TransitTunnel (receiveTunnelID, nextIdent, nextTunnelID, 
 				layerKey, ivKey), m_Gateway(this) {};
 
-			void SendTunnelDataMsg (const uint8_t * gwHash, uint32_t gwTunnel, i2p::I2NPMessage * msg);
+			void SendTunnelDataMsg (i2p::I2NPMessage * msg);
 			size_t GetNumTransmittedBytes () const { return m_Gateway.GetNumSentBytes (); };
 			
 		private:

Transports.cpp

@@ -64,9 +64,12 @@ namespace i2p
 			delete session.second;
 		m_NTCPSessions.clear ();
 		delete m_NTCPAcceptor;
-		
+
-		m_Timer->cancel ();
+		if (m_Timer)
-		delete m_Timer;
+		{	
+			m_Timer->cancel ();
+			delete m_Timer;
+		}
 		
 		if (m_SSUServer)
 		{

Tunnel.cpp

@@ -136,28 +136,28 @@ namespace tunnel
 
 	void OutboundTunnel::SendTunnelDataMsg (const uint8_t * gwHash, uint32_t gwTunnel, i2p::I2NPMessage * msg)
 	{
-		m_Gateway.SendTunnelDataMsg (gwHash, gwTunnel, msg);
+		TunnelMessageBlock block;
+		if (gwHash)
+		{
+			block.hash = gwHash;
+			if (gwTunnel)
+			{	
+				block.deliveryType = eDeliveryTypeTunnel;
+				block.tunnelID = gwTunnel;
+			}	
+			else
+				block.deliveryType = eDeliveryTypeRouter;
+		}	
+		else	
+			block.deliveryType = eDeliveryTypeLocal;
+		block.data = msg;
+		m_Gateway.SendTunnelDataMsg (block);
 	}
 		
 	void OutboundTunnel::SendTunnelDataMsg (std::vector<TunnelMessageBlock> msgs)
 	{
 		for (auto& it : msgs)
-		{
+			m_Gateway.PutTunnelDataMsg (it);
-			switch (it.deliveryType)
-			{
-				case eDeliveryTypeLocal:
-					m_Gateway.SendTunnelDataMsg (nullptr, 0, it.data);
-				break;
-				case eDeliveryTypeTunnel:
-					m_Gateway.SendTunnelDataMsg (it.hash, it.tunnelID, it.data);
-				break;
-				case eDeliveryTypeRouter:
-					m_Gateway.SendTunnelDataMsg (it.hash, 0, it.data);
-				break;	
-				default:
-					LogPrint ("Unexpected delivery type ", (int)it.deliveryType);
-			}	
-		}	
 		m_Gateway.SendBuffer ();
 	}	
 	

Tunnel.h

@@ -21,7 +21,7 @@ namespace i2p
 {
 namespace tunnel
 {	
-	const int TUNNEL_EXPIRATION_TIMEOUT = 600; // 10 minutes	
+	const int TUNNEL_EXPIRATION_TIMEOUT = 660; // 11 minutes	
 	
 	class OutboundTunnel;
 	class InboundTunnel;

TunnelGateway.cpp

@@ -10,7 +10,7 @@ namespace i2p
 {
 namespace tunnel
 {
-	void TunnelGatewayBuffer::PutI2NPMsg (const uint8_t * gwHash, uint32_t gwTunnel, I2NPMessage * msg)
+	void TunnelGatewayBuffer::PutI2NPMsg (const TunnelMessageBlock& block)
 	{
 		if (!m_CurrentTunnelDataMsg)
 			CreateCurrentTunnelDataMessage ();
@@ -18,24 +18,21 @@ namespace tunnel
 		// create delivery instructions
 		uint8_t di[43]; // max delivery instruction length is 43 for tunnel
 		size_t diLen = 1;// flag
-		TunnelDeliveryType dt = eDeliveryTypeLocal;
+		if (block.deliveryType != eDeliveryTypeLocal) // tunnel or router
-		if (gwHash)
 		{	
-			if (gwTunnel)
+			if (block.deliveryType == eDeliveryTypeTunnel)
 			{
-				*(uint32_t *)(di + diLen) = htobe32 (gwTunnel);
+				*(uint32_t *)(di + diLen) = htobe32 (block.tunnelID);
 				diLen += 4; // tunnelID
-				dt = eDeliveryTypeTunnel;
 			}
-			else
-				dt = eDeliveryTypeRouter;
 			
-			memcpy (di + diLen, gwHash, 32);
+			memcpy (di + diLen, block.hash, 32);
 			diLen += 32; //len
 		}	
-		di[0] = dt << 5; // set delivery type
+		di[0] = block.deliveryType << 5; // set delivery type
 
 		// create fragments
+		I2NPMessage * msg = block.data;
 		if (diLen + msg->GetLength () + 2<= m_RemainingSize)
 		{
 			// message fits. First and last fragment
@@ -104,7 +101,7 @@ namespace tunnel
 			{
 				// delivery instructions don't fit. Create new message
 				CompleteCurrentTunnelDataMessage ();
-				PutI2NPMsg (gwHash, gwTunnel, msg);
+				PutI2NPMsg (block);
 				// don't delete msg because it's taken care inside
 			}	
 		}			
@@ -152,15 +149,15 @@ namespace tunnel
 		m_CurrentTunnelDataMsg = nullptr;
 	}	
 	
-	void TunnelGateway::SendTunnelDataMsg (const uint8_t * gwHash, uint32_t gwTunnel, i2p::I2NPMessage * msg)
+	void TunnelGateway::SendTunnelDataMsg (const TunnelMessageBlock& block)
 	{
-		PutTunnelDataMsg (gwHash, gwTunnel, msg);
+		PutTunnelDataMsg (block);
 		SendBuffer ();
 	}	
 
-	void TunnelGateway::PutTunnelDataMsg (const uint8_t * gwHash, uint32_t gwTunnel, i2p::I2NPMessage * msg)
+	void TunnelGateway::PutTunnelDataMsg (const TunnelMessageBlock& block)
 	{
-		m_Buffer.PutI2NPMsg (gwHash, gwTunnel, msg);
+		m_Buffer.PutI2NPMsg (block);
 	}	
 
 	void TunnelGateway::SendBuffer ()

TunnelGateway.h

@@ -15,7 +15,7 @@ namespace tunnel
 		public:
 			TunnelGatewayBuffer (uint32_t tunnelID): m_TunnelID (tunnelID), 
 				m_CurrentTunnelDataMsg (nullptr), m_RemainingSize (0) {};
-			void PutI2NPMsg (const uint8_t * gwHash, uint32_t gwTunnel, I2NPMessage * msg);	
+			void PutI2NPMsg (const TunnelMessageBlock& block);	
 			std::vector<I2NPMessage *> GetTunnelDataMsgs ();
 
 		private:
@@ -37,8 +37,8 @@ namespace tunnel
 
 			TunnelGateway (TunnelBase * tunnel): 
 				m_Tunnel (tunnel), m_Buffer (tunnel->GetNextTunnelID ()), m_NumSentBytes (0) {};
-			void SendTunnelDataMsg (const uint8_t * gwHash, uint32_t gwTunnel, i2p::I2NPMessage * msg);
+			void SendTunnelDataMsg (const TunnelMessageBlock& block);
-			void PutTunnelDataMsg (const uint8_t * gwHash, uint32_t gwTunnel, i2p::I2NPMessage * msg);	
+			void PutTunnelDataMsg (const TunnelMessageBlock& block);	
 			void SendBuffer ();
 			size_t GetNumSentBytes () const { return m_NumSentBytes; };