Possible fix for path issues in 1.6.2

node/Peer.cpp

@@ -120,16 +120,46 @@ void Peer::received(
 			}
 		}
 
-		bool attemptToContact = false;
-		if ((!havePath)&&(RR->node->shouldUsePathForZeroTierTraffic(tPtr,_id.address(),path->localSocket(),path->address()))) {
-			Mutex::Lock _l(_paths_m);
+		if ( (!havePath) && RR->node->shouldUsePathForZeroTierTraffic(tPtr,_id.address(),path->localSocket(),path->address()) ) {
+			if (verb == Packet::VERB_OK) {
+				Mutex::Lock _l(_paths_m);
 
+				unsigned int replacePath = ZT_MAX_PEER_NETWORK_PATHS;
+				long replacePathQuality = 0;
+				for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
+					if (_paths[i].p) {
+						const long q = _paths[i].p->quality(now);
+						if (q > replacePathQuality) {
+							replacePathQuality = q;
+							replacePath = i;
+							if ( (!_paths[i].p->alive(now)) || _paths[i].p->address().ipsEqual(path->address()) )
+								break;
+						}
+					} else {
+						replacePath = i;
+						break;
+					}
+				}
+
+				if (replacePath != ZT_MAX_PEER_NETWORK_PATHS) {
+					RR->t->peerLearnedNewPath(tPtr, networkId, *this, path, packetId);
+					_paths[replacePath].lr = now;
+					_paths[replacePath].p = path;
+					_paths[replacePath].priority = 1;
+				}
+			} else {
+				attemptToContactAt(tPtr,path->localSocket(),path->address(),now,true);
+				path->sent(now);
+				RR->t->peerConfirmingUnknownPath(tPtr,networkId,*this,path,packetId,verb);
+			}
+
+/*
 			// Paths are redunant if they duplicate an alive path to the same IP or
 			// with the same local socket and address family.
 			bool redundant = false;
 			for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
 				if (_paths[i].p) {
-					if ( (_paths[i].p->alive(now)) && ( ((_paths[i].p->localSocket() == path->localSocket())&&(_paths[i].p->address().ss_family == path->address().ss_family)) || (_paths[i].p->address().ipsEqual2(path->address())) ) )  {
+					if ( _paths[i].p->alive(now) && (_paths[i].p->localSocket() == path->localSocket()) && _paths[i].p->address().ipsEqual(path->address()) ) {
 						redundant = true;
 						break;
 					}
@@ -166,12 +196,7 @@ void Peer::received(
 					}
 				}
 			}
-		}
-
-		if (attemptToContact) {
-			attemptToContactAt(tPtr,path->localSocket(),path->address(),now,true);
-			path->sent(now);
-			RR->t->peerConfirmingUnknownPath(tPtr,networkId,*this,path,packetId,verb);
+*/
 		}
 	}