Make sure IPv6 sockets are IPv6 only.

diff --git a/src/net_socket.c b/src/net_socket.c
index 44b7ec7..808e1c6 100644 (file)
--- a/src/net_socket.c
+++ b/src/net_socket.c
@@ -99,6 +99,11 @@ 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)
@@ -177,6 +182,11 @@ 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;
@@ -320,6 +330,12 @@ 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);