Nexthop calculation should always use the shortest path.

[tinc] / src / graph.c

diff --git a/src/graph.c b/src/graph.c
index 396e35a..8f20ec7 100644 (file)
--- a/src/graph.c
+++ b/src/graph.c
@@ -176,9 +176,13 @@ static void sssp_bfs(void) {
                           && (e->to->distance != n->distance + 1 || e->weight >= e->to->prevedge->weight))
                                continue;
 
+                       // Only update nexthop if it doesn't increase the path length
+
+                       if(!e->to->status.visited || (e->to->distance == n->distance + 1 && e->weight >= e->to->prevedge->weight))
+                               e->to->nexthop = (n->nexthop == myself) ? e->to : n->nexthop;
+
                        e->to->status.visited = true;
                        e->to->status.indirect = indirect;
-                       e->to->nexthop = (n->nexthop == myself) ? e->to : n->nexthop;
                        e->to->prevedge = e;
                        e->to->via = indirect ? n->via : e->to;
                        e->to->options = e->options;