Make sure the packet source MAC address is always set.

[tinc] / src / net_packet.c

diff --git a/src/net_packet.c b/src/net_packet.c
index 69835ee..6f72e05 100644 (file)
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -458,7 +458,7 @@ bool receive_tcppacket_sptps(connection_t *c, const char *data, int len) {
                /* This can happen in the form of a race condition
                   if the node just became unreachable. */
                logger(DEBUG_TRAFFIC, LOG_WARNING, "Cannot relay TCP packet from %s (%s) because the destination, %s (%s), is unreachable", from->name, from->hostname, to->name, to->hostname);
-               return;
+               return true;
        }
 
        /* Help the sender reach us over UDP.
@@ -1252,8 +1252,12 @@ void send_packet(node_t *n, vpn_packet_t *packet) {
        // If it's for myself, write it to the tun/tap device.
 
        if(n == myself) {
-               if(overwrite_mac)
+               if(overwrite_mac) {
                         memcpy(DATA(packet), mymac.x, ETH_ALEN);
+                        // Use an arbitrary fake source address.
+                        memcpy(DATA(packet) + ETH_ALEN, DATA(packet), ETH_ALEN);
+                        DATA(packet)[ETH_ALEN * 2 - 1] ^= 0xFF;
+               }
                n->out_packets++;
                n->out_bytes += packet->len;
                devops.write(packet);