connectd: prefer non-TOR connections and filter wireaddr hint duplicate

This does two things:
 - It moves non-tor addresses upfront so it prefers normal connection
   which are less laggy and more reliable.
 - It prevents connectd from trying the same wire_addr twice when the
   addr_hint was given and gossip also added the same address.

Changelog-Changed: connectd: try non-TOR connections first
Changelog-Fixed: connectd: do not try address hint twice

Author: m-schmoock

connectd/connectd.c

@@ -1459,9 +1459,18 @@ static void add_seed_addrs(struct wireaddr_internal **addrs,
 	}
 }
 
+static bool wireaddr_int_equals_wireaddr(struct wireaddr_internal *addr_a,
+					 struct wireaddr *addr_b)
+{
+	if (!addr_a || !addr_b)
+		return false;
+	return wireaddr_eq(&addr_a->u.wireaddr, addr_b);
+}
+
 /*~ This asks gossipd for any addresses advertized by the node. */
 static void add_gossip_addrs(struct wireaddr_internal **addrs,
-			     const struct node_id *id)
+			     const struct node_id *id,
+			     struct wireaddr_internal *addrhint)
 {
 	u8 *msg;
 	struct wireaddr *normal_addrs;
@@ -1483,6 +1492,24 @@ static void add_gossip_addrs(struct wireaddr_internal **addrs,
 
 	/* Wrap each one in a wireaddr_internal and add to addrs. */
 	for (size_t i = 0; i < tal_count(normal_addrs); i++) {
+		/* add TOR addresses in a second loop */
+		if (normal_addrs[i].type == ADDR_TYPE_TOR_V2 ||
+		    normal_addrs[i].type == ADDR_TYPE_TOR_V3)
+			continue;
+		if (wireaddr_int_equals_wireaddr(addrhint, &normal_addrs[i]))
+			continue;
+		struct wireaddr_internal addr;
+		addr.itype = ADDR_INTERNAL_WIREADDR;
+		addr.u.wireaddr = normal_addrs[i];
+		tal_arr_expand(addrs, addr);
+	}
+	/* so connectd prefers direct connections if possible. */
+	for (size_t i = 0; i < tal_count(normal_addrs); i++) {
+		if (normal_addrs[i].type != ADDR_TYPE_TOR_V2 &&
+		    normal_addrs[i].type != ADDR_TYPE_TOR_V3)
+			continue;
+		if (wireaddr_int_equals_wireaddr(addrhint, &normal_addrs[i]))
+			continue;
 		struct wireaddr_internal addr;
 		addr.itype = ADDR_INTERNAL_WIREADDR;
 		addr.u.wireaddr = normal_addrs[i];
@@ -1524,10 +1551,11 @@ static void try_connect_peer(struct daemon *daemon,
 	addrs = tal_arr(tmpctx, struct wireaddr_internal, 0);
 
 	/* They can supply an optional address for the connect RPC */
+	/* We add this first so its tried first by connectd */
 	if (addrhint)
 		tal_arr_expand(&addrs, *addrhint);
 
-	add_gossip_addrs(&addrs, id);
+	add_gossip_addrs(&addrs, id, addrhint);
 
 	if (tal_count(addrs) == 0) {
 		/* Don't resolve via DNS seed if we're supposed to use proxy. */