+struct gre_config {
+ uint32_t local_ip;
+ uint32_t remote_ip;
+ uint32_t in_key;
+ uint32_t out_key;
+ uint8_t tos;
+ bool have_in_key;
+ bool have_out_key;
+ bool in_csum;
+ bool out_csum;
+ bool pmtud;
+};
+
+static struct {
+ union {
+ struct nl_sock *nl_sock;
+ int ioctl_fd;
+ };
+ bool use_ioctl;
+} gre_descriptors;
+
+struct netdev_linux_notifier {
+ struct netdev_notifier notifier;
+ struct list node;
+};
+
+static struct shash netdev_linux_notifiers =
+ SHASH_INITIALIZER(&netdev_linux_notifiers);
+static struct rtnetlink_notifier netdev_linux_poll_notifier;
+
+/* This is set pretty low because we probably won't learn anything from the
+ * additional log messages. */
+static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
+
+static int if_up(const char *name);
+static int destroy_gre(const char *name);
+static int netdev_linux_do_ethtool(const char *name, struct ethtool_cmd *,
+ int cmd, const char *cmd_name);
+static int netdev_linux_do_ioctl(const char *name, struct ifreq *, int cmd,
+ const char *cmd_name);
+static int netdev_linux_get_ipv4(const struct netdev *, struct in_addr *,
+ int cmd, const char *cmd_name);
+static int get_flags(const struct netdev *, int *flagsp);
+static int set_flags(struct netdev *, int flags);
+static int do_get_ifindex(const char *netdev_name);
+static int get_ifindex(const struct netdev *, int *ifindexp);
+static int do_set_addr(struct netdev *netdev,
+ int ioctl_nr, const char *ioctl_name,
+ struct in_addr addr);
+static int get_etheraddr(const char *netdev_name, uint8_t ea[ETH_ADDR_LEN]);
+static int set_etheraddr(const char *netdev_name, int hwaddr_family,
+ const uint8_t[ETH_ADDR_LEN]);
+static int get_stats_via_netlink(int ifindex, struct netdev_stats *stats);
+static int get_stats_via_proc(const char *netdev_name, struct netdev_stats *stats);
+
+static struct netdev_dev_linux *
+netdev_dev_linux_cast(const struct netdev_dev *netdev_dev)
+{
+ const char *type = netdev_dev_get_type(netdev_dev);
+ assert(!strcmp(type, "system") || !strcmp(type, "tap")
+ || !strcmp(type, "gre") || !strcmp(type, "patch"));
+ return CONTAINER_OF(netdev_dev, struct netdev_dev_linux, netdev_dev);
+}
+
+static struct netdev_linux *
+netdev_linux_cast(const struct netdev *netdev)
+{
+ const char *type = netdev_get_type(netdev);
+ assert(!strcmp(type, "system") || !strcmp(type, "tap")
+ || !strcmp(type, "gre") || !strcmp(type, "patch"));
+ return CONTAINER_OF(netdev, struct netdev_linux, netdev);
+}
+
+static int
+netdev_linux_init(void)
+{
+ static int status = -1;
+ if (status < 0) {
+ af_inet_sock = socket(AF_INET, SOCK_DGRAM, 0);
+ status = af_inet_sock >= 0 ? 0 : errno;
+ if (status) {
+ VLOG_ERR("failed to create inet socket: %s", strerror(status));
+ }
+ }
+ return status;
+}
+
+static void
+netdev_linux_run(void)
+{
+ rtnetlink_notifier_run();
+}
+
+static void
+netdev_linux_wait(void)
+{
+ rtnetlink_notifier_wait();
+}
+
+static void
+netdev_linux_cache_cb(const struct rtnetlink_change *change,
+ void *aux OVS_UNUSED)
+{
+ struct netdev_dev_linux *dev;
+ if (change) {
+ struct netdev_dev *base_dev = netdev_dev_from_name(change->ifname);
+ if (base_dev) {
+ dev = netdev_dev_linux_cast(base_dev);
+ dev->cache_valid = 0;
+ }
+ } else {
+ struct shash device_shash;
+ struct shash_node *node;
+
+ shash_init(&device_shash);
+ netdev_dev_get_devices(&netdev_linux_class, &device_shash);
+ SHASH_FOR_EACH (node, &device_shash) {
+ dev = node->data;
+ dev->cache_valid = 0;
+ }
+ shash_destroy(&device_shash);
+ }
+}
+
+/* The arguments are marked as unused to prevent warnings on platforms where
+ * the Netlink interface isn't supported. */
+static int
+setup_gre_netlink(const char *name OVS_UNUSED,
+ struct gre_config *config OVS_UNUSED, bool create OVS_UNUSED)
+{
+#ifdef GRE_IOCTL_ONLY
+ return EOPNOTSUPP;
+#else
+ int error;
+ struct ofpbuf request, *reply;
+ unsigned int nl_flags;
+ struct ifinfomsg ifinfomsg;
+ struct nlattr *linkinfo_hdr;
+ struct nlattr *info_data_hdr;
+ uint16_t iflags = 0;
+ uint16_t oflags = 0;
+
+ VLOG_DBG("%s: attempting to create gre device using netlink", name);
+
+ if (!gre_descriptors.nl_sock) {
+ error = nl_sock_create(NETLINK_ROUTE, 0, 0, 0,
+ &gre_descriptors.nl_sock);
+ if (error) {
+ VLOG_WARN("couldn't create netlink socket: %s", strerror(error));
+ goto error;
+ }
+ }
+
+ ofpbuf_init(&request, 0);
+
+ nl_flags = NLM_F_REQUEST;
+ if (create) {
+ nl_flags |= NLM_F_CREATE|NLM_F_EXCL;
+ }
+
+ /* We over-reserve space, because we do some pointer arithmetic
+ * and don't want the buffer address shifting under us. */
+ nl_msg_put_nlmsghdr(&request, gre_descriptors.nl_sock, 2048, RTM_NEWLINK,
+ nl_flags);
+
+ memset(&ifinfomsg, 0, sizeof ifinfomsg);
+ ifinfomsg.ifi_family = AF_UNSPEC;
+ nl_msg_put(&request, &ifinfomsg, sizeof ifinfomsg);
+
+ linkinfo_hdr = ofpbuf_tail(&request);
+ nl_msg_put_unspec(&request, IFLA_LINKINFO, NULL, 0);
+
+ nl_msg_put_unspec(&request, IFLA_INFO_KIND, "gretap", 6);
+
+ info_data_hdr = ofpbuf_tail(&request);
+ nl_msg_put_unspec(&request, IFLA_INFO_DATA, NULL, 0);
+
+ /* Set flags */
+ if (config->have_in_key) {
+ iflags |= GRE_KEY;
+ }
+ if (config->have_out_key) {
+ oflags |= GRE_KEY;
+ }
+
+ if (config->in_csum) {
+ iflags |= GRE_CSUM;
+ }
+ if (config->out_csum) {
+ oflags |= GRE_CSUM;
+ }
+
+ /* Add options */
+ nl_msg_put_u32(&request, IFLA_GRE_IKEY, config->in_key);
+ nl_msg_put_u32(&request, IFLA_GRE_OKEY, config->out_key);
+ nl_msg_put_u16(&request, IFLA_GRE_IFLAGS, iflags);
+ nl_msg_put_u16(&request, IFLA_GRE_OFLAGS, oflags);
+ nl_msg_put_u32(&request, IFLA_GRE_LOCAL, config->local_ip);
+ nl_msg_put_u32(&request, IFLA_GRE_REMOTE, config->remote_ip);
+ nl_msg_put_u8(&request, IFLA_GRE_PMTUDISC, config->pmtud);
+ nl_msg_put_u8(&request, IFLA_GRE_TTL, IPDEFTTL);
+ nl_msg_put_u8(&request, IFLA_GRE_TOS, config->tos);
+
+ info_data_hdr->nla_len = (char *)ofpbuf_tail(&request)
+ - (char *)info_data_hdr;
+ linkinfo_hdr->nla_len = (char *)ofpbuf_tail(&request)
+ - (char *)linkinfo_hdr;
+
+ nl_msg_put_string(&request, IFLA_IFNAME, name);
+
+ error = nl_sock_transact(gre_descriptors.nl_sock, &request, &reply);
+ ofpbuf_uninit(&request);
+ if (error) {
+ VLOG_WARN("couldn't transact netlink socket: %s", strerror(error));
+ goto error;
+ }
+ ofpbuf_delete(reply);
+
+error:
+ return error;
+#endif
+}
+
+static int
+setup_gre_ioctl(const char *name, struct gre_config *config, bool create)
+{
+ struct ip_tunnel_parm p;
+ struct ifreq ifr;
+
+ VLOG_DBG("%s: attempting to create gre device using ioctl", name);
+
+ memset(&p, 0, sizeof p);
+
+ strncpy(p.name, name, IFNAMSIZ);
+
+ p.iph.version = 4;
+ p.iph.ihl = 5;
+ p.iph.protocol = IPPROTO_GRE;
+ p.iph.saddr = config->local_ip;
+ p.iph.daddr = config->remote_ip;
+ p.iph.ttl = IPDEFTTL;
+ p.iph.tos = config->tos;
+
+ if (config->have_in_key) {
+ p.i_flags |= GRE_KEY;
+ p.i_key = config->in_key;
+ }
+ if (config->have_out_key) {
+ p.o_flags |= GRE_KEY;
+ p.o_key = config->out_key;
+ }
+
+ if (config->in_csum) {
+ p.i_flags |= GRE_CSUM;
+ }
+ if (config->out_csum) {
+ p.o_flags |= GRE_CSUM;
+ }
+
+ if (config->pmtud) {
+ p.iph.frag_off = htons(IP_DONT_FRAGMENT);
+ }
+
+ strncpy(ifr.ifr_name, create ? GRE_IOCTL_DEVICE : name, IFNAMSIZ);
+ ifr.ifr_ifru.ifru_data = (void *)&p;
+
+ if (!gre_descriptors.ioctl_fd) {
+ gre_descriptors.ioctl_fd = socket(AF_INET, SOCK_DGRAM, 0);
+ if (gre_descriptors.ioctl_fd < 0) {
+ VLOG_WARN("couldn't create gre ioctl socket: %s", strerror(errno));
+ gre_descriptors.ioctl_fd = 0;
+ return errno;
+ }
+ }
+
+ if (ioctl(gre_descriptors.ioctl_fd, create ? SIOCADDGRETAP : SIOCCHGGRETAP,
+ &ifr) < 0) {
+ VLOG_WARN("couldn't do gre ioctl: %s", strerror(errno));
+ return errno;
+ }
+
+ return 0;
+}
+
+/* The arguments are marked as unused to prevent warnings on platforms where
+ * the Netlink interface isn't supported. */
+static bool
+check_gre_device_netlink(const char *name OVS_UNUSED)
+{
+#ifdef GRE_IOCTL_ONLY
+ return false;
+#else
+ static const struct nl_policy getlink_policy[] = {
+ [IFLA_LINKINFO] = { .type = NL_A_NESTED, .optional = false },
+ };
+
+ static const struct nl_policy linkinfo_policy[] = {
+ [IFLA_INFO_KIND] = { .type = NL_A_STRING, .optional = false },
+ };
+
+ int error;
+ bool ret = false;
+ struct ofpbuf request, *reply;
+ struct ifinfomsg ifinfomsg;
+ struct nlattr *getlink_attrs[ARRAY_SIZE(getlink_policy)];
+ struct nlattr *linkinfo_attrs[ARRAY_SIZE(linkinfo_policy)];
+ struct ofpbuf linkinfo;
+ const char *device_kind;
+
+ ofpbuf_init(&request, 0);
+
+ nl_msg_put_nlmsghdr(&request, gre_descriptors.nl_sock,
+ NLMSG_LENGTH(sizeof ifinfomsg), RTM_GETLINK,
+ NLM_F_REQUEST);
+
+ memset(&ifinfomsg, 0, sizeof ifinfomsg);
+ ifinfomsg.ifi_family = AF_UNSPEC;
+ ifinfomsg.ifi_index = do_get_ifindex(name);
+ nl_msg_put(&request, &ifinfomsg, sizeof ifinfomsg);
+
+ error = nl_sock_transact(gre_descriptors.nl_sock, &request, &reply);
+ ofpbuf_uninit(&request);
+ if (error) {
+ VLOG_WARN("couldn't transact netlink socket: %s", strerror(error));
+ return false;
+ }
+
+ if (!nl_policy_parse(reply, NLMSG_HDRLEN + sizeof(struct ifinfomsg),
+ getlink_policy, getlink_attrs,
+ ARRAY_SIZE(getlink_policy))) {
+ VLOG_WARN("received bad rtnl message (getlink policy)");
+ goto error;
+ }
+
+ linkinfo.data = (void *)nl_attr_get(getlink_attrs[IFLA_LINKINFO]);
+ linkinfo.size = nl_attr_get_size(getlink_attrs[IFLA_LINKINFO]);
+ if (!nl_policy_parse(&linkinfo, 0, linkinfo_policy,
+ linkinfo_attrs, ARRAY_SIZE(linkinfo_policy))) {
+ VLOG_WARN("received bad rtnl message (linkinfo policy)");
+ goto error;
+ }
+
+ device_kind = nl_attr_get_string(linkinfo_attrs[IFLA_INFO_KIND]);
+ ret = !strcmp(device_kind, "gretap");
+
+error:
+ ofpbuf_delete(reply);
+ return ret;
+#endif
+}
+
+static bool
+check_gre_device_ioctl(const char *name)
+{
+ struct ethtool_drvinfo drvinfo;
+ int error;
+
+ memset(&drvinfo, 0, sizeof drvinfo);
+ error = netdev_linux_do_ethtool(name, (struct ethtool_cmd *)&drvinfo,
+ ETHTOOL_GDRVINFO, "ETHTOOL_GDRVINFO");
+
+ return !error && !strcmp(drvinfo.driver, "ip_gre")
+ && !strcmp(drvinfo.bus_info, "gretap");
+}
+
+static int
+setup_gre(const char *name, const struct shash *args, bool create)
+{
+ int error;
+ struct in_addr in_addr;
+ struct shash_node *node;
+ struct gre_config config;
+
+ memset(&config, 0, sizeof config);
+ config.in_csum = true;
+ config.out_csum = true;
+ config.pmtud = true;
+
+ SHASH_FOR_EACH (node, args) {
+ if (!strcmp(node->name, "remote_ip")) {
+ if (lookup_ip(node->data, &in_addr)) {
+ VLOG_WARN("bad 'remote_ip' for gre device %s ", name);
+ } else {
+ config.remote_ip = in_addr.s_addr;
+ }
+ } else if (!strcmp(node->name, "local_ip")) {
+ if (lookup_ip(node->data, &in_addr)) {
+ VLOG_WARN("bad 'local_ip' for gre device %s ", name);
+ } else {
+ config.local_ip = in_addr.s_addr;
+ }
+ } else if (!strcmp(node->name, "key")) {
+ config.have_in_key = true;
+ config.have_out_key = true;
+ config.in_key = htonl(atoi(node->data));
+ config.out_key = htonl(atoi(node->data));
+ } else if (!strcmp(node->name, "in_key")) {
+ config.have_in_key = true;
+ config.in_key = htonl(atoi(node->data));
+ } else if (!strcmp(node->name, "out_key")) {
+ config.have_out_key = true;
+ config.out_key = htonl(atoi(node->data));
+ } else if (!strcmp(node->name, "tos")) {
+ config.tos = atoi(node->data);
+ } else if (!strcmp(node->name, "csum")) {
+ if (!strcmp(node->data, "false")) {
+ config.in_csum = false;
+ config.out_csum = false;
+ }
+ } else if (!strcmp(node->name, "pmtud")) {
+ if (!strcmp(node->data, "false")) {
+ config.pmtud = false;
+ }
+ } else {
+ VLOG_WARN("unknown gre argument '%s'", node->name);
+ }
+ }
+
+ if (!config.remote_ip) {
+ VLOG_WARN("gre type requires valid 'remote_ip' argument");
+ error = EINVAL;
+ goto error;
+ }
+
+ if (!gre_descriptors.use_ioctl) {
+ error = setup_gre_netlink(name, &config, create);
+ if (error == EOPNOTSUPP) {
+ gre_descriptors.use_ioctl = true;
+ }
+ }
+ if (gre_descriptors.use_ioctl) {
+ error = setup_gre_ioctl(name, &config, create);
+ }
+
+ if (create && error == EEXIST) {
+ bool gre_device;
+
+ if (gre_descriptors.use_ioctl) {
+ gre_device = check_gre_device_ioctl(name);
+ } else {
+ gre_device = check_gre_device_netlink(name);
+ }
+
+ if (!gre_device) {
+ goto error;
+ }
+
+ VLOG_WARN("replacing existing gre device %s", name);
+ error = destroy_gre(name);
+ if (error) {
+ goto error;
+ }
+
+ if (gre_descriptors.use_ioctl) {
+ error = setup_gre_ioctl(name, &config, create);
+ } else {
+ error = setup_gre_netlink(name, &config, create);
+ }
+ }
+
+error:
+ return error;
+}
+
+/* A veth may be created using the 'command' "+<name>,<peer>". A veth may
+ * be destroyed by using the 'command' "-<name>", where <name> can be
+ * either side of the device.
+ */
+static int
+modify_veth(const char *format, ...)
+{
+ FILE *veth_file;
+ va_list args;
+ int retval;
+
+ veth_file = fopen("/sys/class/net/veth_pairs", "w");
+ if (!veth_file) {
+ VLOG_WARN_RL(&rl, "could not open veth device. Are you running a "
+ "supported XenServer with the kernel module loaded?");
+ return ENODEV;
+ }
+ setvbuf(veth_file, NULL, _IONBF, 0);
+
+ va_start(args, format);
+ retval = vfprintf(veth_file, format, args);
+ va_end(args);
+
+ fclose(veth_file);
+ if (retval < 0) {
+ VLOG_WARN_RL(&rl, "could not destroy patch: %s", strerror(errno));
+ return errno;
+ }
+
+ return 0;
+}
+
+static int
+create_patch(const char *name, const char *peer)
+{
+ int retval;
+ struct netdev_dev *peer_nd;
+
+
+ /* Only create the veth if the peer didn't already do it. */
+ peer_nd = netdev_dev_from_name(peer);
+ if (peer_nd) {
+ if (!strcmp("patch", netdev_dev_get_type(peer_nd))) {
+ struct netdev_dev_linux *ndl = netdev_dev_linux_cast(peer_nd);
+ if (!strcmp(name, ndl->state.patch.peer)) {
+ return 0;
+ } else {
+ VLOG_WARN_RL(&rl, "peer '%s' already paired with '%s'",
+ peer, ndl->state.patch.peer);
+ return EINVAL;
+ }
+ } else {
+ VLOG_WARN_RL(&rl, "peer '%s' exists and is not a patch", peer);
+ return EINVAL;
+ }
+ }
+
+ retval = modify_veth("+%s,%s", name, peer);
+ if (retval) {
+ return retval;
+ }
+
+ retval = if_up(name);
+ if (retval) {
+ return retval;
+ }
+
+ retval = if_up(peer);
+ if (retval) {
+ return retval;
+ }
+
+ return 0;
+}
+
+static int
+setup_patch(const char *name, const struct shash *args, char **peer_)
+{
+ const char *peer;
+
+ peer = shash_find_data(args, "peer");
+ if (!peer) {
+ VLOG_WARN("patch type requires valid 'peer' argument");
+ return EINVAL;
+ }
+
+ if (shash_count(args) > 1) {
+ VLOG_WARN("patch type takes only a 'peer' argument");
+ return EINVAL;
+ }
+
+ if (strlen(peer) >= IFNAMSIZ) {
+ VLOG_WARN_RL(&rl, "patch 'peer' arg too long");
+ return EINVAL;
+ }
+
+ *peer_ = xstrdup(peer);
+ return create_patch(name, peer);
+}
+
+/* Creates the netdev device of 'type' with 'name'. */
+static int
+netdev_linux_create_system(const char *name, const char *type OVS_UNUSED,
+ const struct shash *args, struct netdev_dev **netdev_devp)
+{
+ struct netdev_dev_linux *netdev_dev;
+ int error;
+
+ if (!shash_is_empty(args)) {
+ VLOG_WARN("%s: arguments for system devices should be empty", name);
+ }
+
+ if (!cache_notifier_refcount) {
+ error = rtnetlink_notifier_register(&netdev_linux_cache_notifier,
+ netdev_linux_cache_cb, NULL);
+ if (error) {
+ return error;
+ }
+ }
+ cache_notifier_refcount++;
+
+ netdev_dev = xzalloc(sizeof *netdev_dev);
+ netdev_dev_init(&netdev_dev->netdev_dev, name, &netdev_linux_class);
+
+ *netdev_devp = &netdev_dev->netdev_dev;
+ return 0;
+}
+
+/* For most types of netdevs we open the device for each call of
+ * netdev_open(). However, this is not the case with tap devices,
+ * since it is only possible to open the device once. In this
+ * situation we share a single file descriptor, and consequently
+ * buffers, across all readers. Therefore once data is read it will
+ * be unavailable to other reads for tap devices. */
+static int
+netdev_linux_create_tap(const char *name, const char *type OVS_UNUSED,
+ const struct shash *args, struct netdev_dev **netdev_devp)
+{
+ struct netdev_dev_linux *netdev_dev;
+ struct tap_state *state;
+ static const char tap_dev[] = "/dev/net/tun";
+ struct ifreq ifr;
+ int error;
+
+ if (!shash_is_empty(args)) {
+ VLOG_WARN("%s: arguments for TAP devices should be empty", name);
+ }
+
+ netdev_dev = xzalloc(sizeof *netdev_dev);
+ state = &netdev_dev->state.tap;
+
+ /* Open tap device. */
+ state->fd = open(tap_dev, O_RDWR);
+ if (state->fd < 0) {
+ error = errno;
+ VLOG_WARN("opening \"%s\" failed: %s", tap_dev, strerror(error));
+ goto error;
+ }
+
+ /* Create tap device. */
+ ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+ strncpy(ifr.ifr_name, name, sizeof ifr.ifr_name);
+ if (ioctl(state->fd, TUNSETIFF, &ifr) == -1) {
+ VLOG_WARN("%s: creating tap device failed: %s", name,
+ strerror(errno));
+ error = errno;
+ goto error;
+ }
+
+ /* Make non-blocking. */
+ error = set_nonblocking(state->fd);
+ if (error) {
+ goto error;
+ }
+
+ netdev_dev_init(&netdev_dev->netdev_dev, name, &netdev_tap_class);
+ *netdev_devp = &netdev_dev->netdev_dev;
+ return 0;
+
+error:
+ free(netdev_dev);
+ return error;
+}
+
+static int
+if_up(const char *name)
+{
+ struct ifreq ifr;
+
+ strncpy(ifr.ifr_name, name, sizeof ifr.ifr_name);
+ ifr.ifr_flags = IFF_UP;
+
+ if (ioctl(af_inet_sock, SIOCSIFFLAGS, &ifr) == -1) {
+ VLOG_DBG_RL(&rl, "%s: failed to bring device up: %s",
+ name, strerror(errno));
+ return errno;
+ }
+
+ return 0;
+}
+
+static int
+netdev_linux_create_gre(const char *name, const char *type OVS_UNUSED,
+ const struct shash *args, struct netdev_dev **netdev_devp)
+{
+ struct netdev_dev_linux *netdev_dev;
+ int error;
+
+ netdev_dev = xzalloc(sizeof *netdev_dev);
+
+ error = setup_gre(name, args, true);
+ if (error) {
+ goto error;
+ }
+
+ error = if_up(name);
+ if (error) {
+ goto error;
+ }
+
+ netdev_dev_init(&netdev_dev->netdev_dev, name, &netdev_gre_class);
+ *netdev_devp = &netdev_dev->netdev_dev;
+ return 0;
+
+error:
+ free(netdev_dev);
+ return error;
+}
+
+static int
+netdev_linux_create_patch(const char *name, const char *type OVS_UNUSED,
+ const struct shash *args, struct netdev_dev **netdev_devp)
+{
+ struct netdev_dev_linux *netdev_dev;
+ char *peer = NULL;
+ int error;
+
+ error = setup_patch(name, args, &peer);
+ if (error) {
+ free(peer);
+ return error;
+ }
+
+ netdev_dev = xzalloc(sizeof *netdev_dev);
+ netdev_dev->state.patch.peer = peer;
+ netdev_dev_init(&netdev_dev->netdev_dev, name, &netdev_patch_class);
+ *netdev_devp = &netdev_dev->netdev_dev;
+
+ return 0;
+}
+
+static int
+netdev_linux_reconfigure_gre(struct netdev_dev *netdev_dev_,
+ const struct shash *args)
+{
+ const char *name = netdev_dev_get_name(netdev_dev_);
+
+ return setup_gre(name, args, false);
+}
+
+/* The arguments are marked as unused to prevent warnings on platforms where
+ * the Netlink interface isn't supported. */
+static int
+destroy_gre_netlink(const char *name OVS_UNUSED)
+{
+#ifdef GRE_IOCTL_ONLY
+ return EOPNOTSUPP;
+#else
+ int error;
+ struct ofpbuf request, *reply;
+ struct ifinfomsg ifinfomsg;
+ int ifindex;
+
+ ofpbuf_init(&request, 0);
+
+ nl_msg_put_nlmsghdr(&request, gre_descriptors.nl_sock, 0, RTM_DELLINK,
+ NLM_F_REQUEST);
+
+ memset(&ifinfomsg, 0, sizeof ifinfomsg);
+ ifinfomsg.ifi_family = AF_UNSPEC;
+ nl_msg_put(&request, &ifinfomsg, sizeof ifinfomsg);
+
+ ifindex = do_get_ifindex(name);
+ nl_msg_put_u32(&request, IFLA_LINK, ifindex);
+
+ nl_msg_put_string(&request, IFLA_IFNAME, name);
+
+ error = nl_sock_transact(gre_descriptors.nl_sock, &request, &reply);
+ ofpbuf_uninit(&request);
+ if (error) {
+ VLOG_WARN("couldn't transact netlink socket: %s", strerror(error));
+ goto error;
+ }
+ ofpbuf_delete(reply);
+
+error:
+ return 0;
+#endif
+}
+
+static int
+destroy_gre_ioctl(const char *name)
+{
+ struct ip_tunnel_parm p;
+ struct ifreq ifr;
+
+ memset(&p, 0, sizeof p);
+ strncpy(p.name, name, IFNAMSIZ);