Detect and prevent two nodes with the same Name being on the VPN simultaneously.

[tinc] / src / net.c

diff --git a/src/net.c b/src/net.c
index a04ba00..ee58ac0 100644 (file)
--- a/src/net.c
+++ b/src/net.c
@@ -44,6 +44,8 @@ bool do_purge = false;
 volatile bool running = false;
 
 time_t now = 0;
+int contradicting_add_edge = 0;
+int contradicting_del_edge = 0;
 
 /* Purge edges and subnets of unreachable nodes. Use carefully. */
 
@@ -297,7 +299,7 @@ static void check_network_activity(fd_set * readset, fd_set * writeset) {
                if(FD_ISSET(c->socket, readset)) {
                        if(c->status.connecting) {
                                c->status.connecting = false;
-                               getsockopt(c->socket, SOL_SOCKET, SO_ERROR, &result, &len);
+                               getsockopt(c->socket, SOL_SOCKET, SO_ERROR, (void *)&result, &len);
 
                                if(!result)
                                        finish_connecting(c);
@@ -415,6 +417,19 @@ int main_loop(void) {
                                send_key_changed(broadcast, myself);
                                keyexpires = now + keylifetime;
                        }
+
+                       if(contradicting_del_edge && contradicting_add_edge) {
+                               logger(LOG_WARNING, "Possible node with same Name as us!");
+
+                               if(rand() % 3 == 0) {
+                                       logger(LOG_ERR, "Shutting down, check configuration of all nodes for duplicate Names!");
+                                       running = false;
+                                       break;
+                               }
+
+                               contradicting_add_edge = 0;
+                               contradicting_del_edge = 0;
+                       }
                }
 
                if(sigalrm) {