Let tinc figure out the exact MTU of the link.

[tinc] / src / net_socket.c

diff --git a/src/net_socket.c b/src/net_socket.c
index 4e4a008..f740431 100644 (file)
--- a/src/net_socket.c
+++ b/src/net_socket.c
@@ -17,7 +17,7 @@
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 
-    $Id: net_socket.c,v 1.1.2.35 2003/12/12 19:52:25 guus Exp $
+    $Id: net_socket.c,v 1.1.2.36 2003/12/20 19:47:52 guus Exp $
 */
 
 #include "system.h"
@@ -49,13 +49,10 @@ int listen_sockets;
 
 int setup_listen_socket(const sockaddr_t *sa)
 {
-       int nfd, flags;
+       int nfd;
        char *addrstr;
        int option;
        char *iface;
-#ifdef SO_BINDTODEVICE
-       struct ifreq ifr;
-#endif
 
        cp();
 
@@ -67,13 +64,15 @@ int setup_listen_socket(const sockaddr_t *sa)
        }
 
 #ifdef O_NONBLOCK
-       flags = fcntl(nfd, F_GETFL);
+       {
+               int flags = fcntl(nfd, F_GETFL);
 
-       if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) {
-               closesocket(nfd);
-               logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl",
-                          strerror(errno));
-               return -1;
+               if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) {
+                       closesocket(nfd);
+                       logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl",
+                                  strerror(errno));
+                       return -1;
+               }
        }
 #endif
 
@@ -94,6 +93,8 @@ int setup_listen_socket(const sockaddr_t *sa)
        if(get_config_string
           (lookup_config(config_tree, "BindToInterface"), &iface)) {
 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
+               struct ifreq ifr;
+
                memset(&ifr, 0, sizeof(ifr));
                strncpy(ifr.ifr_ifrn.ifrn_name, iface, IFNAMSIZ);
 
@@ -129,13 +130,9 @@ int setup_listen_socket(const sockaddr_t *sa)
 
 int setup_vpn_in_socket(const sockaddr_t *sa)
 {
-       int nfd, flags;
+       int nfd;
        char *addrstr;
        int option;
-#if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
-       char *iface;
-       struct ifreq ifr;
-#endif
 
        cp();
 
@@ -147,29 +144,51 @@ int setup_vpn_in_socket(const sockaddr_t *sa)
        }
 
 #ifdef O_NONBLOCK
-       flags = fcntl(nfd, F_GETFL);
-       if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) {
-               closesocket(nfd);
-               logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl",
-                          strerror(errno));
-               return -1;
+       {
+               int flags = fcntl(nfd, F_GETFL);
+
+               if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) {
+                       closesocket(nfd);
+                       logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl",
+                                  strerror(errno));
+                       return -1;
+               }
        }
 #endif
 
        option = 1;
        setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(option));
 
-#if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
-       if(get_config_string
-          (lookup_config(config_tree, "BindToInterface"), &iface)) {
-               memset(&ifr, 0, sizeof(ifr));
-               strncpy(ifr.ifr_ifrn.ifrn_name, iface, IFNAMSIZ);
+#if defined(SOL_IP) && defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DO)
+       {
+               bool choice;
+
+               if(get_config_bool(lookup_config(myself->connection->config_tree, "DontFragment"), &choice) && choice) {
+                       option = IP_PMTUDISC_DO;
+                       if(setsockopt(nfd, SOL_IP, IP_MTU_DISCOVER, &option, sizeof(option))) {
+                               closesocket(nfd);
+                               logger(LOG_ERR, _("Can't set MTU discovery mode: %s"), strerror(errno));
+                               return -1;
+                       }
+               }
+       }
+#endif
 
-               if(setsockopt(nfd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr))) {
-                       closesocket(nfd);
-                       logger(LOG_ERR, _("Can't bind to interface %s: %s"), iface,
-                                  strerror(errno));
-                       return -1;
+#if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
+       {
+               char *iface;
+               struct ifreq ifr;
+
+               if(get_config_string(lookup_config(config_tree, "BindToInterface"), &iface)) {
+                       memset(&ifr, 0, sizeof(ifr));
+                       strncpy(ifr.ifr_ifrn.ifrn_name, iface, IFNAMSIZ);
+
+                       if(setsockopt(nfd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr))) {
+                               closesocket(nfd);
+                               logger(LOG_ERR, _("Can't bind to interface %s: %s"), iface,
+                                          strerror(errno));
+                               return -1;
+                       }
                }
        }
 #endif