Make sure IPv6 sockets are IPv6 only.

[tinc] / src / net_socket.c

diff --git a/src/net_socket.c b/src/net_socket.c
index bf5130d..2ed685d 100644 (file)
--- a/src/net_socket.c
+++ b/src/net_socket.c
@@ -102,6 +102,11 @@ int setup_listen_socket(const sockaddr_t *sa)
        option = 1;
        setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(option));
 
+#if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
+       if(sa->sa.sa_family == AF_INET6)
+               setsockopt(nfd, SOL_IPV6, IPV6_V6ONLY, &option, sizeof option);
+#endif
+
        if(get_config_string
           (lookup_config(config_tree, "BindToInterface"), &iface)) {
 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
@@ -181,6 +186,11 @@ int setup_vpn_in_socket(const sockaddr_t *sa)
        option = 1;
        setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(option));
 
+#if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
+       if(sa->sa.sa_family == AF_INET6)
+               setsockopt(nfd, SOL_IPV6, IPV6_V6ONLY, &option, sizeof option);
+#endif
+
 #if defined(SOL_IP) && defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DO)
        {
                bool choice;
@@ -300,7 +310,8 @@ begin:
        }
 
        if(!c->outgoing->aip) {
-               freeaddrinfo(c->outgoing->ai);
+               if(c->outgoing->ai)
+                       freeaddrinfo(c->outgoing->ai);
                c->outgoing->ai = NULL;
                goto begin;
        }
@@ -325,6 +336,12 @@ begin:
                goto begin;
        }
 
+#if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
+       int option = 1;
+       if(c->address.sa.sa_family == AF_INET6)
+               setsockopt(c->socket, SOL_IPV6, IPV6_V6ONLY, &option, sizeof option);
+#endif
+
        /* Optimize TCP settings */
 
        configure_tcp(c);