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 fc5720a..6f72e05 100644 (file)
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -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);