check if address is still introducer before trying to introduce

libi2pd/SSU2.cpp

@@ -785,8 +785,12 @@ namespace transport
 				auto it1 = m_SessionsByRouterHash.find (it.iH);
 				if (it1 != m_SessionsByRouterHash.end ())
 				{
-					it1->second->Introduce (session, it.iTag);
+					auto addr = it1->second->GetAddress ();
-					return;
+					if (addr && addr->IsIntroducer ())
+					{	
+						it1->second->Introduce (session, it.iTag);
+						return;
+					}	
 				}
 				else
 					indices.push_back(i);
@@ -815,12 +819,12 @@ namespace transport
 					{
 						relayTag = introducer.iTag;
 						addr = address->IsV6 () ? r->GetSSU2V6Address () : r->GetSSU2V4Address ();
-						if (addr && !addr->host.is_unspecified () && addr->port &&
+						if (addr && addr->IsIntroducer () && !addr->host.is_unspecified () && addr->port &&
 							!i2p::transport::transports.IsInReservedRange(addr->host))
 							break;
 						else
 						{
-							// address is invalid try another SSU2 address if exists
+							// address is invalid or not intrudcer, try another SSU2 address if exists
 							if (address->IsV4 ())
 							{
 								if (i2p::context.SupportsV6 ())
@@ -831,7 +835,7 @@ namespace transport
 								if (i2p::context.SupportsV4 ())
 									addr = r->GetSSU2V4Address ();
 							}	
-							if (addr && !addr->host.is_unspecified () && addr->port &&
+							if (addr && addr->IsIntroducer () && !addr->host.is_unspecified () && addr->port &&
 								!i2p::transport::transports.IsInReservedRange(addr->host))
 								break;
 							else

libi2pd/SSU2Session.cpp

@@ -1125,6 +1125,13 @@ namespace transport
 			LogPrint (eLogError, "SSU2: RouterInfo in SessionConfirmed is from future for ", (ri->GetTimestamp () - ts)/1000LL, " seconds");
 			return false;
 		}	
+		// update RouterInfo in netdb
+		ri = i2p::data::netdb.AddRouterInfo (ri->GetBuffer (), ri->GetBufferLen ()); // ri points to one from netdb now
+		if (!ri)
+		{
+			LogPrint (eLogError, "SSU2: Couldn't update RouterInfo from SessionConfirmed in netdb");
+			return false;
+		}
 		m_Address = m_RemoteEndpoint.address ().is_v6 () ? ri->GetSSU2V6Address () : ri->GetSSU2V4Address ();
 		if (!m_Address || memcmp (S, m_Address->s, 32))
 		{
@@ -1139,13 +1146,6 @@ namespace transport
 				" and actual endpoint ", m_RemoteEndpoint.address (), " from ", i2p::data::GetIdentHashAbbreviation (ri->GetIdentHash ()));
 			return false;
 		}
-		// update RouterInfo in netdb
-		ri = i2p::data::netdb.AddRouterInfo (ri->GetBuffer (), ri->GetBufferLen ()); // ri points to one from netdb now
-		if (!ri)
-		{
-			LogPrint (eLogError, "SSU2: Couldn't update RouterInfo from SessionConfirmed in netdb");
-			return false;
-		}
 		SetRemoteIdentity (ri->GetRouterIdentity ());
 		AdjustMaxPayloadSize ();
 		m_Server.AddSessionByRouterHash (shared_from_this ()); // we know remote router now