don't connect to unpublished NTCP2 addresses

libi2pd/NTCP2.cpp

@@ -590,7 +590,7 @@ namespace transport
 			uint8_t * decrypted = new uint8_t[m_NextReceivedLen];
 			if (i2p::crypto::AEADChaCha20Poly1305 (m_NextReceivedBuffer, m_NextReceivedLen-16, nullptr, 0, m_ReceiveKey, nonce, decrypted, m_NextReceivedLen, false))
 			{	
-				LogPrint (eLogInfo, "NTCP2: received message decrypted");
+				LogPrint (eLogDebug, "NTCP2: received message decrypted");
 				ProcessNextFrame (decrypted, m_NextReceivedLen-16);
 				ReceiveLength ();
 			}

libi2pd/RouterInfo.cpp

@@ -259,6 +259,7 @@ namespace data
 					if (!address->ntcp2) address->ntcp2.reset (new NTCP2Ext ());
 					supportedTransports |= (address->host.is_v4 ()) ? eNTCP2V4 : eNTCP2V6;
 					Base64ToByteStream (value, strlen (value), address->ntcp2->iv, 16);	
+					address->ntcp2->isPublished = true; // presence if "i" means "published"
 				}	
 				else if (key[0] == 'i')
 				{
@@ -292,7 +293,7 @@ namespace data
 				if (!s) return;
 			}
 			if (introducers) supportedTransports |= eSSUV4; // in case if host is not presented
-			if (supportedTransports && !isNtcp2) // we ignore NTCP2 addresses for now. TODO:
+			if (supportedTransports && (!isNtcp2 || address->IsPublishedNTCP2 ())) // we ignore unpublished NTCP2 only addresses 
 			{
 				addresses->push_back(address);
 				m_SupportedTransports |= supportedTransports;

libi2pd/RouterInfo.h

@@ -94,6 +94,7 @@ namespace data
 			{
 				Tag<32> staticKey;
 				Tag<16> iv;
+				bool isPublished = false;
 			};
 
 			struct Address
@@ -124,6 +125,7 @@ namespace data
 				}
 
 				bool IsNTCP2 () const { return (bool)ntcp2; };
+				bool IsPublishedNTCP2 () const { return IsNTCP2 () && ntcp2->isPublished; };
 			};
 			typedef std::list<std::shared_ptr<Address> > Addresses;
 

libi2pd/Transports.cpp

@@ -405,7 +405,7 @@ namespace transport
 			{
 				peer.numAttempts++;
 				auto address = peer.router->GetNTCPAddress (!context.SupportsV6 ());
-				if (address && address->IsNTCP2 () && m_NTCP2Server) // NTCP2 have priority over NTCP if enabled
+				if (address && address->IsPublishedNTCP2 () && m_NTCP2Server) // NTCP2 have priority over NTCP if enabled
 				{
 					auto s = std::make_shared<NTCP2Session> (*m_NTCP2Server, peer.router);
 					m_NTCP2Server->Connect (address->host, address->port, s);