+/* 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 UNUSED, struct gre_config *config UNUSED,
+ bool create 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;
+ uint8_t pmtudisc = 0;
+
+ 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\n", strerror(error));
+ gre_descriptors.nl_sock = NULL;
+ 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, pmtudisc);
+ nl_msg_put_u8(&request, IFLA_GRE_TTL, 0);
+ nl_msg_put_u8(&request, IFLA_GRE_TOS, 0);
+
+ 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\n", 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;
+
+ 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;
+
+ 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;
+ }
+
+ 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\n", 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\n", strerror(errno));
+ return errno;
+ }
+
+ return 0;
+}
+
+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;
+
+ 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, "csum")) {
+ if (!strcmp(node->data, "false")) {
+ config.in_csum = false;
+ config.out_csum = 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);
+ }
+
+error:
+ 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;
+}
+
+/* Creates the netdev object of 'type' with 'name'. */
+static int
+netdev_linux_create_system(const char *name, const char *type UNUSED,
+ const struct shash *args, bool created)
+{
+ struct netdev_obj_linux *netdev_obj;
+
+ if (!shash_is_empty(args)) {
+ VLOG_WARN("arguments for system devices should be empty");
+ }
+
+ netdev_obj = xcalloc(1, sizeof *netdev_obj);
+ netdev_obj_init(&netdev_obj->netdev_obj, name, &netdev_linux_class,
+ created);
+
+ return 0;
+}
+
+static int
+netdev_linux_create_tap(const char *name, const char *type UNUSED,
+ const struct shash *args, bool created)
+{
+ struct netdev_obj_linux *netdev_obj;
+ struct tap_state *state;
+ static const char tap_dev[] = "/dev/net/tun";
+ struct ifreq ifr;
+ int error;
+
+ if (!shash_is_empty(args)) {
+ VLOG_WARN("arguments for TAP devices should be empty");
+ }
+
+ netdev_obj = xcalloc(1, sizeof *netdev_obj);
+ netdev_obj_init(&netdev_obj->netdev_obj, name, &netdev_tap_class, created);
+
+ state = &netdev_obj->state.tap;
+
+ /* Open tap device. */
+ state->tap_fd = open(tap_dev, O_RDWR);
+ if (state->tap_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->tap_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->tap_fd);
+ if (error) {
+ goto error;
+ }
+
+ error = if_up(name);
+ if (error) {
+ goto error;
+ }
+
+ return 0;
+
+error:
+ netdev_destroy(name);
+ return error;
+}
+
+static int
+netdev_linux_create_gre(const char *name, const char *type UNUSED,
+ const struct shash *args, bool created)
+{
+ struct netdev_obj_linux *netdev_obj;
+ int error;
+
+ netdev_obj = xcalloc(1, sizeof *netdev_obj);
+ netdev_obj_init(&netdev_obj->netdev_obj, name, &netdev_gre_class, created);
+
+ error = setup_gre(name, args, true);
+ if (error) {
+ goto error;
+ }
+
+ error = if_up(name);
+ if (error) {
+ goto error;
+ }
+
+ return 0;
+
+error:
+ netdev_destroy(name);
+ return error;
+}
+
+static int
+netdev_linux_reconfigure_gre(struct netdev_obj *netdev_obj_,
+ const struct shash *args)
+{
+ struct netdev_obj_linux *netdev_obj = netdev_obj_linux_cast(netdev_obj_);
+ const char *name = netdev_obj_get_name(&netdev_obj->netdev_obj);
+
+ 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(struct netdev_obj_linux *netdev_obj UNUSED)
+{
+#ifdef GRE_IOCTL_ONLY
+ return EOPNOTSUPP;
+#else
+ const char *name = netdev_obj_get_name(&netdev_obj->netdev_obj);
+ 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\n", strerror(error));
+ goto error;
+ }
+ ofpbuf_delete(reply);
+
+error:
+ return 0;
+#endif
+}
+
+static int
+destroy_gre_ioctl(struct netdev_obj_linux *netdev_obj)
+{
+ const char *name = netdev_obj_get_name(&netdev_obj->netdev_obj);
+ struct ip_tunnel_parm p;
+ struct ifreq ifr;
+
+ memset(&p, 0, sizeof p);
+ strncpy(p.name, name, IFNAMSIZ);
+
+ strncpy(ifr.ifr_name, name, IFNAMSIZ);
+ ifr.ifr_ifru.ifru_data = (void *)&p;
+
+ if (ioctl(gre_descriptors.ioctl_fd, SIOCDELGRETAP, &ifr) < 0) {
+ VLOG_WARN("couldn't do gre ioctl: %s\n", strerror(errno));
+ return errno;
+ }
+
+ return 0;
+}
+
+static void
+destroy_tap(struct netdev_obj_linux *netdev_obj)
+{
+ struct tap_state *state = &netdev_obj->state.tap;
+ if (state->tap_fd >= 0) {
+ close(state->tap_fd);
+ }
+}
+
+/* Destroys the netdev object 'netdev_obj_'. */
+static void
+netdev_linux_destroy(struct netdev_obj *netdev_obj_)
+{
+ struct netdev_obj_linux *netdev_obj = netdev_obj_linux_cast(netdev_obj_);
+ const char *type = netdev_obj_get_type(netdev_obj_);
+
+ if (!strcmp(type, "tap")) {
+ destroy_tap(netdev_obj);
+ } else if (!strcmp(type, "gre")) {
+ if (gre_descriptors.use_ioctl) {
+ destroy_gre_ioctl(netdev_obj);
+ } else {
+ destroy_gre_netlink(netdev_obj);
+ }
+ }
+ free(netdev_obj);
+}
+