don't try introducer with invalid address. Terminate session immediately if appropriate introducer not found

libi2pd/SSU2.cpp

@@ -796,6 +796,7 @@ namespace transport
 		// we have to start a new session to an introducer
 		std::vector<i2p::data::IdentHash> newRouters;
 		std::shared_ptr<i2p::data::RouterInfo> r;
+		std::shared_ptr<const i2p::data::RouterInfo::Address> addr;
 		uint32_t relayTag = 0;
 		if (!indices.empty ())
 		{
@@ -812,7 +813,16 @@ namespace transport
 					if (r->IsReachableFrom (i2p::context.GetRouterInfo ()))
 					{
 						relayTag = introducer.iTag;
-						if (relayTag) break;
+						addr = address->IsV6 () ? r->GetSSU2V6Address () : r->GetSSU2V4Address ();
+						if (!addr->host.is_unspecified () && addr->port &&
+							!i2p::transport::transports.IsInReservedRange(addr->host))
+							break;
+						else
+						{
+							// address is invalid, try next introducer
+							relayTag = 0;
+							addr = nullptr;
+						}	
 					}
 				}	
 				else if (!i2p::data::IsRouterBanned (introducer.iH))
@@ -821,16 +831,9 @@ namespace transport
 		}
 		if (r)
 		{
-			if (relayTag)
+			if (relayTag && addr)
 			{
 				// introducer and tag found connect to it through SSU2
-				auto addr = address->IsV6 () ? r->GetSSU2V6Address () : r->GetSSU2V4Address ();
-				if (addr)
-				{
-					bool isValidEndpoint = !addr->host.is_unspecified () && addr->port &&
-						!i2p::transport::transports.IsInReservedRange(addr->host);
-					if (isValidEndpoint)
-					{
 				auto s = FindPendingOutgoingSession (boost::asio::ip::udp::endpoint (addr->host, addr->port));
 				if (!s)
 				{
@@ -851,14 +854,15 @@ namespace transport
 						s->SetOnEstablished ([session, s, relayTag]() {s->Introduce (session, relayTag); });
 				}
 			}
-				}
-			}
+			else
+				session->Done ();
 		}
 		else
 		{
 			// introducers not found, try to request them
 			for (auto& it: newRouters)
 				i2p::data::netdb.RequestDestination (it);
+			session->Done (); // don't wait for connect timeout
 		}
 	}