Use destination address of ppp interfaces as nexthop in starters default route lookup

diff --git a/src/starter/interfaces.c b/src/starter/interfaces.c
index ba16a39..92b2c74 100644 (file)
--- a/src/starter/interfaces.c
+++ b/src/starter/interfaces.c
@@ -132,7 +132,6 @@ get_defaultroute(defaultroute_t *defaultroute)
                }
 
                if (metric < best_metric
-               &&  gw.s_addr != INADDR_ANY
                &&  iface_idx != -1)
                {
                        struct ifreq req;
@@ -141,19 +140,39 @@ get_defaultroute(defaultroute_t *defaultroute)
                        if (fd < 0)
                        {
                                plog("could not open AF_INET socket");
-                               defaultroute->defined = FALSE;
                                break;
                        }
                        bzero(&req, sizeof(req));
                        req.ifr_ifindex = iface_idx;
-                       ioctl(fd, SIOCGIFNAME, &req);
-                       ioctl(fd, SIOCGIFADDR, &req);
-                       close(fd);
+                       if (ioctl(fd, SIOCGIFNAME, &req) < 0 ||
+                               ioctl(fd, SIOCGIFADDR, &req) < 0)
+                       {
+                               plog("could not read interface data, ignoring route");
+                               close(fd);
+                               break;
+                       }
 
                        strncpy(defaultroute->iface, req.ifr_name, IFNAMSIZ);
                        defaultroute->addr.u.v4 = *((struct sockaddr_in *) &req.ifr_addr);
                        defaultroute->nexthop.u.v4.sin_family = AF_INET;
-                       defaultroute->nexthop.u.v4.sin_addr = gw;
+
+                       if (gw.s_addr == INADDR_ANY)
+                       {
+                               if (ioctl(fd, SIOCGIFDSTADDR, &req) < 0 ||
+                                       ((struct sockaddr_in*) &req.ifr_dstaddr)->sin_addr.s_addr == INADDR_ANY)
+                               {
+                                       DBG_log("Ignoring default route to device %s because we can't get it's destination",
+                                                       req.ifr_name);
+                                       close(fd);
+                                       break;
+                               }
+
+                               defaultroute->nexthop.u.v4 = *((struct sockaddr_in *) &req.ifr_dstaddr);
+                       }
+                       else
+                               defaultroute->nexthop.u.v4.sin_addr = gw;
+
+                       close(fd);
 
                        DBG(DBG_CONTROL,
                                char addr[20];