From: Guus Sliepen <guus@meshlink.io>
Date: Sun, 11 Oct 2020 13:40:34 +0000 (+0200)
Subject: Don't reset the UDP SPTPS session when a node becomes reachable.
X-Git-Url: https://git.meshlink.io/?a=commitdiff_plain;h=77315aaa984e9a5821cf3ddbf3017db98204728c;p=meshlink

Don't reset the UDP SPTPS session when a node becomes reachable.

Only do this when it becomes unreachable. This fixes an issue where right
after a meta-connection is established, the initiator sends a proactive
REQ_KEY, before the peer really becomes reachable according to the graph.
When the latter happened, it would reset the session so far, causing a new
REQ_KEY to be sent, which could cross the ANS_KEY from the peer. This would
resolve itself after a few seconds, but causes an unnecessary delay that is
easy to trigger.
---

diff --git a/src/graph.c b/src/graph.c
index 1efdb26c..56ef11db 100644
--- a/src/graph.c
+++ b/src/graph.c
@@ -193,10 +193,13 @@ static void check_reachability(meshlink_handle_t *mesh) {
 
 			/* TODO: only clear status.validkey if node is unreachable? */
 
-			n->status.validkey = false;
-			sptps_stop(&n->sptps);
-			n->status.waitingforkey = false;
-			n->last_req_key = -3600;
+			if(!n->status.reachable) {
+				logger(mesh, MESHLINK_DEBUG, "Resetting validkey/waitingforkey for %s, reachable %d", n->name, n->status.reachable);
+				n->status.validkey = false;
+				sptps_stop(&n->sptps);
+				n->status.waitingforkey = false;
+				n->last_req_key = -3600;
+			}
 
 			n->status.udp_confirmed = false;
 			n->maxmtu = MTU;