From: Guus Sliepen <guus@meshlink.io>
Date: Mon, 16 Nov 2020 19:57:46 +0000 (+0100)
Subject: Don't try to renew SPTPS keys for unreachable nodes.
X-Git-Url: https://git.meshlink.io/?a=commitdiff_plain;h=refs%2Fheads%2Ffix%2Fdeterministic-sptps-reset;p=meshlink

Don't try to renew SPTPS keys for unreachable nodes.

This caused other functions that incorrectly used status.validkey to check
if they could send data to a node to pass a NULL pointer to send_request(),
causing a crash about an hour after a node went offline.
---

diff --git a/src/net.c b/src/net.c
index 5689a040..8bec6b67 100644
--- a/src/net.c
+++ b/src/net.c
@@ -627,7 +627,7 @@ static void periodic_handler(event_loop_t *loop, void *data) {
 			n->status.dirty = false;
 		}
 
-		if(n->status.validkey && n->last_req_key + 3600 < mesh->loop.now.tv_sec) {
+		if(n->status.reachable && n->status.validkey && n->last_req_key + 3600 < mesh->loop.now.tv_sec) {
 			logger(mesh, MESHLINK_DEBUG, "SPTPS key renewal for node %s", n->name);
 			devtool_sptps_renewal_probe((meshlink_node_t *)n);
 
diff --git a/src/net_packet.c b/src/net_packet.c
index 3ee0eaec..38200e5a 100644
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -245,6 +245,11 @@ static bool try_mac(meshlink_handle_t *mesh, node_t *n, const vpn_packet_t *inpk
 }
 
 static void receive_udppacket(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *inpkt) {
+	if(!n->status.reachable) {
+		logger(mesh, MESHLINK_ERROR, "Got SPTPS data from unreachable node %s", n->name);
+		return;
+	}
+
 	if(!n->sptps.state) {
 		if(!n->status.waitingforkey) {
 			logger(mesh, MESHLINK_DEBUG, "Got packet from %s but we haven't exchanged keys yet", n->name);
@@ -262,6 +267,11 @@ static void receive_udppacket(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *
 }
 
 static void send_sptps_packet(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *origpkt) {
+	if(!n->status.reachable) {
+		logger(mesh, MESHLINK_ERROR, "Trying to send SPTPS data to unreachable node %s", n->name);
+		return;
+	}
+
 	if(!n->status.validkey) {
 		logger(mesh, MESHLINK_INFO, "No valid key known yet for %s", n->name);
 
@@ -379,6 +389,11 @@ bool send_sptps_data(void *handle, uint8_t type, const void *data, size_t len) {
 	node_t *to = handle;
 	meshlink_handle_t *mesh = to->mesh;
 
+	if(!to->status.reachable) {
+		logger(mesh, MESHLINK_ERROR, "Trying to send SPTPS data to unreachable node %s", to->name);
+		return false;
+	}
+
 	/* Send it via TCP if it is a handshake packet, TCPOnly is in use, or this packet is larger than the MTU. */
 
 	if(type >= SPTPS_HANDSHAKE || (type != PKT_PROBE && (len - 21) > to->minmtu)) {