+ return system_bridge_if(bridge->ifname, dev, SIOCBRDELIF);
+}
+
+static bool system_is_bridge(const char *name, char *buf, int buflen)
+{
+ struct stat st;
+
+ snprintf(buf, buflen, "/sys/devices/virtual/net/%s/bridge", name);
+ if (stat(buf, &st) < 0)
+ return false;
+
+ return true;
+}
+
+static char *system_get_bridge(const char *name, char *buf, int buflen)
+{
+ char *path;
+ ssize_t len;
+ glob_t gl;
+
+ snprintf(buf, buflen, "/sys/devices/virtual/net/*/brif/%s/bridge", name);
+ if (glob(buf, GLOB_NOSORT, NULL, &gl) < 0)
+ return NULL;
+
+ if (gl.gl_pathc == 0)
+ return NULL;
+
+ len = readlink(gl.gl_pathv[0], buf, buflen);
+ if (len < 0)
+ return NULL;
+
+ buf[len] = 0;
+ path = strrchr(buf, '/');
+ if (!path)
+ return NULL;
+
+ return path + 1;
+}
+
+static int system_if_resolve(struct device *dev)
+{
+ struct ifreq ifr;
+ strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));
+ if (!ioctl(sock_ioctl, SIOCGIFINDEX, &ifr))
+ return ifr.ifr_ifindex;
+ else
+ return 0;
+}
+
+static int system_if_flags(const char *ifname, unsigned add, unsigned rem)
+{
+ struct ifreq ifr;
+ strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
+ ioctl(sock_ioctl, SIOCGIFFLAGS, &ifr);
+ ifr.ifr_flags |= add;
+ ifr.ifr_flags &= ~rem;
+ return ioctl(sock_ioctl, SIOCSIFFLAGS, &ifr);
+}
+
+/*
+ * Clear bridge (membership) state and bring down device
+ */
+static void system_if_clear_state(struct device *dev)
+{
+ char buf[256];
+ char *bridge;
+
+ dev->ifindex = system_if_resolve(dev);
+ if (!dev->ifindex)
+ return;
+
+ system_if_flags(dev->ifname, 0, IFF_UP);
+
+ if (system_is_bridge(dev->ifname, buf, sizeof(buf))) {
+ D(SYSTEM, "Delete existing bridge named '%s'\n", dev->ifname);
+ system_bridge_delbr(dev);
+ return;
+ }
+
+ bridge = system_get_bridge(dev->ifname, buf, sizeof(buf));
+ if (bridge) {
+ D(SYSTEM, "Remove device '%s' from bridge '%s'\n", dev->ifname, bridge);
+ system_bridge_if(bridge, dev, SIOCBRDELIF);
+ }
+}
+
+int system_bridge_addbr(struct device *bridge)
+{
+ system_if_clear_state(bridge);
+ return ioctl(sock_ioctl, SIOCBRADDBR, bridge->ifname);