X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fpmtu.c;h=0d5e8fd528ba59821ce43ed10bba555104924685;hb=e57f522ee2fef5a229a59f8fa08f94555fe3ec32;hp=4073825cfdc56f65d722395f257516fb81fed820;hpb=322eef8bc2ca53e1b7778f33bc9fb3af498cb9bc;p=meshlink

diff --git a/src/pmtu.c b/src/pmtu.c
index 4073825c..0d5e8fd5 100644
--- a/src/pmtu.c
+++ b/src/pmtu.c
@@ -91,8 +91,16 @@ static void udp_probe_timeout_handler(event_loop_t *loop, void *data) {
 	logger(mesh, MESHLINK_INFO, "Too much time has elapsed since last UDP ping response from %s, stopping UDP communication", n->name);
 	n->status.udp_confirmed = false;
 	n->mtuprobes = 0;
+	n->udpprobes = 0;
 	n->minmtu = 0;
 	n->maxmtu = MTU;
+
+	// If we also have a meta-connection to this node, send a PING on it as well
+	connection_t *c = n->connection;
+
+	if(c && !c->status.pinged) {
+		send_ping(mesh, c);
+	}
 }
 
 static void send_udp_probe_reply(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *packet, uint16_t len) {
@@ -115,7 +123,7 @@ static void send_udp_probe_reply(meshlink_handle_t *mesh, node_t *n, vpn_packet_
 	bool udp_confirmed = n->status.udp_confirmed;
 	n->status.udp_confirmed = true;
 	logger(mesh, MESHLINK_DEBUG, "Sending UDP reply length %d to %s", packet->len, n->name);
-	n->out_meta += packet->len;
+	n->out_meta += packet->len + SPTPS_DATAGRAM_OVERHEAD;
 	send_udppacket(mesh, n, packet);
 	n->status.udp_confirmed = udp_confirmed;
 }
@@ -126,7 +134,7 @@ void udp_probe_h(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *packet, uint1
 		return;
 	}
 
-	n->in_meta += packet->len;
+	n->in_meta += packet->len + SPTPS_DATAGRAM_OVERHEAD;
 
 	if(!packet->data[0]) {
 		/* It's a probe request, send back a reply */
@@ -154,6 +162,8 @@ void udp_probe_h(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *packet, uint1
 		n->status.udp_confirmed = true;
 	}
 
+	n->udpprobes = 0;
+
 	// Reset the UDP ping timer.
 
 	timeout_del(&mesh->loop, &n->udp_ping_timeout);
@@ -205,21 +215,40 @@ static void send_udp_probe_packet(meshlink_handle_t *mesh, node_t *n, int len) {
 
 	logger(mesh, MESHLINK_DEBUG, "Sending UDP probe length %d to %s", len, n->name);
 
-	n->out_meta += packet.len;
+	n->out_meta += packet.len + SPTPS_DATAGRAM_OVERHEAD;
 	send_udppacket(mesh, n, &packet);
 }
 
 static void try_udp(meshlink_handle_t *mesh, node_t *n) {
 	/* Probe request */
 
+	if(n->status.udp_confirmed && n->udpprobes < -3) {
+		/* We lost three UDP probes, UDP status is no longer unconfirmed */
+		udp_probe_timeout_handler(&mesh->loop, n);
+	}
+
 	struct timespec elapsed;
+
 	timespec_sub(&mesh->loop.now, &n->last_udp_probe_sent, &elapsed);
 
-	int interval = n->status.udp_confirmed ? 10 : 2;
+	int interval;
+
+	if(n->status.udp_confirmed && n->udpprobes >= 0) {
+		// UDP confirmed and no lost probes, default interval
+		interval = 10;
+	} else if(n->udpprobes <= -15) {
+		// Many probes lost in a row, slow probing interval
+		n->udpprobes = -15;
+		interval = 10;
+	} else {
+		// Fast probing if we don't know the state of UDP connectivity yet
+		interval = 2;
+	}
 
 	if(elapsed.tv_sec >= interval) {
 		n->last_udp_probe_sent = mesh->loop.now;
 		send_udp_probe_packet(mesh, n, MIN_PROBE_SIZE);
+		n->udpprobes--;
 
 		if(!n->status.udp_confirmed && n->prevedge) {
 			n->status.broadcast = true;
@@ -286,6 +315,7 @@ static uint16_t choose_initial_maxmtu(meshlink_handle_t *mesh, node_t *n) {
 	return mtu;
 
 #else
+	(void)mesh;
 	(void)n;
 	return MTU;
 #endif