As a last resort, match packets to processes when only the local part matches

Helps for applications with many short-lived connections (such as bittorrent)
and is correct except for exotic use cases anyway

connection.cpp

@@ -165,13 +165,24 @@ void Connection::add (Packet * packet)
 	}
 }
 
-/* 
- * finds connection to which this packet belongs.
- * a packet belongs to a connection if it matches
- * to its reference packet 
- */
-Connection * findConnection (Packet * packet)
-{
+Connection * findConnectionWithMatchingSource(Packet * packet) {
+	assert(packet->Outgoing());
+
+	ConnList * current = connections;
+	while (current != NULL)
+	{
+		/* the reference packet is always outgoing */
+		if (packet->matchSource(current->getVal()->refpacket))
+		{
+			return current->getVal();
+		}
+
+		current = current->getNext();
+	}
+	return NULL;
+}
+
+Connection * findConnectionWithMatchingRefpacketOrSource(Packet * packet) {
 	ConnList * current = connections;
 	while (current != NULL)
 	{
@@ -183,25 +194,26 @@ Connection * findConnection (Packet * packet)
 
 		current = current->getNext();
 	}
+	return findConnectionWithMatchingSource(packet);
+}
 
-	// Try again, now with the packet inverted:
-	current = connections;
-	Packet * invertedPacket = packet->newInverted();
-
-	while (current != NULL)
+/* 
+ * finds connection to which this packet belongs.
+ * a packet belongs to a connection if it matches
+ * to its reference packet 
+ */
+Connection * findConnection (Packet * packet)
+{
+	if (packet->Outgoing())
+		return findConnectionWithMatchingRefpacketOrSource(packet);
+	else
 	{
-		/* the reference packet is always *outgoing* */
-		if (invertedPacket->match(current->getVal()->refpacket))
-		{
-			delete invertedPacket;
-			return current->getVal();
-		}
+		Packet * invertedPacket = packet->newInverted();
+		Connection * result = findConnectionWithMatchingRefpacketOrSource(invertedPacket);
 
-		current = current->getNext();
+		delete invertedPacket;
+		return result;
 	}
-
-	delete invertedPacket;
-	return NULL;
 }
 
 /*

packet.cpp

@@ -231,11 +231,12 @@ bool Packet::Outgoing () {
 		  	dir = dir_outgoing;
 		  	return true;
 		} else {
-		  	/*if (DEBUG) {
+		  	if (DEBUG) {
 				if (sa_family == AF_INET)
 					islocal = local_addrs->contains(dip.s_addr);
 				else
 					islocal = local_addrs->contains(dip6);
+
 				if (!islocal) {
 					std::cerr << "Neither dip nor sip are local: ";
 					char addy [50];
@@ -246,7 +247,7 @@ bool Packet::Outgoing () {
 
 					return false;
 				}
-		  	}*/
+		  	}
 		  	dir = dir_incoming;
 		  	return false;
 		}
@@ -273,7 +274,7 @@ char * Packet::gethashstring ()
 		inet_ntop(sa_family, &dip, remote_string, 49);
 	} else {
 		inet_ntop(sa_family, &sip6, local_string,  49);
-		inet_ntop(sa_family, &dip6, remote_string, 49);
+inet_ntop(sa_family, &dip6, remote_string, 49);
 	}
 	if (Outgoing()) {
 		snprintf(hashstring, HASHKEYSIZE * sizeof(char), "%s:%d-%s:%d", local_string, sport, remote_string, dport);
@@ -294,3 +295,8 @@ bool Packet::match (Packet * other)
 	return (sport == other->sport) && (dport == other->dport)
 		&& (sameinaddr(sip, other->sip)) && (sameinaddr(dip, other->dip));
 }
+
+bool Packet::matchSource (Packet * other)
+{
+	return (sport == other->sport) && (sameinaddr(sip, other->sip)); 
+}

packet.h

@@ -74,6 +74,7 @@ public:
 	bool Outgoing ();
 
 	bool match (Packet * other);
+	bool matchSource (Packet * other);
 	/* returns '1.2.3.4:5-1.2.3.4:6'-style string */
 	char * gethashstring();
 private: