drop second incoming connection with same identity

SSUSession.cpp

@@ -759,6 +759,11 @@ namespace transport
 		transports.PeerDisconnected (shared_from_this ());
 	}	
 
+	void SSUSession::Terminate ()
+	{
+		m_Server.DeleteSession (shared_from_this ());
+	}
+
 	void SSUSession::Established ()
 	{
 		m_State = eSessionStateEstablished;

SSUSession.h

@@ -63,6 +63,7 @@ namespace transport
 			void Introduce (uint32_t iTag, const uint8_t * iKey);
 			void WaitForIntroduction ();
 			void Close ();
+			void Terminate ();
 			boost::asio::ip::udp::endpoint& GetRemoteEndpoint () { return m_RemoteEndpoint; };
 			bool IsV6 () const { return m_RemoteEndpoint.address ().is_v6 (); };
 			void SendI2NPMessage (I2NPMessage * msg);

TransportSession.h

@@ -62,6 +62,7 @@ namespace transport
 			}
 
 			virtual ~TransportSession () { delete m_DHKeysPair; };
+			virtual void Terminate () = 0;
 			
 			std::shared_ptr<const i2p::data::RouterInfo> GetRemoteRouter () { return m_RemoteRouter; };
 			const i2p::data::IdentityEx& GetRemoteIdentity () { return m_RemoteIdentity; };

Transports.cpp

@@ -405,9 +405,17 @@ namespace transport
 			auto it = m_Peers.find (ident);
 			if (it != m_Peers.end ())
 			{
-				it->second.session = session;
-				session->SendI2NPMessages (it->second.delayedMessages);
-				it->second.delayedMessages.clear ();
+				if (!it->second.session)
+				{
+					it->second.session = session;
+					session->SendI2NPMessages (it->second.delayedMessages);
+					it->second.delayedMessages.clear ();
+				}
+				else
+				{
+					LogPrint (eLogError, "Session for ", ident.ToBase64 ().substr (0, 4), " already exists");
+					session->Terminate ();
+				}
 			}
 			else // incoming connection
 				m_Peers[ident] = { 0, nullptr, session };
@@ -420,7 +428,7 @@ namespace transport
 		{  
 			auto ident = session->GetRemoteIdentity ().GetIdentHash ();
 			auto it = m_Peers.find (ident);
-			if (it != m_Peers.end ())
+			if (it != m_Peers.end () && it->second.session == session)
 			{
 				if (it->second.delayedMessages.size () > 0)
 					ConnectToPeer (ident, it->second);