+ 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;