+
+#ifndef IP_DF
+#define IP_DF 0x4000
+#endif
+
+static void tunnel_parm_init(struct ip_tunnel_parm *p)
+{
+ memset(p, 0, sizeof(*p));
+ p->iph.version = 4;
+ p->iph.ihl = 5;
+ p->iph.frag_off = htons(IP_DF);
+}
+
+static int tunnel_ioctl(const char *name, int cmd, void *p)
+{
+ struct ifreq ifr;
+
+ memset(&ifr, 0, sizeof(ifr));
+ strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
+ ifr.ifr_ifru.ifru_data = p;
+ return ioctl(sock_ioctl, cmd, &ifr);
+}
+
+int system_del_ip_tunnel(const char *name)
+{
+ struct ip_tunnel_parm p;
+
+ tunnel_parm_init(&p);
+ return tunnel_ioctl(name, SIOCDELTUNNEL, &p);
+}
+
+static int parse_ipaddr(struct blob_attr *attr, __be32 *addr)
+{
+ if (!attr)
+ return 1;
+
+ return inet_pton(AF_INET, blobmsg_data(attr), (void *) addr);
+}
+
+
+int system_add_ip_tunnel(const char *name, struct blob_attr *attr)
+{
+ struct blob_attr *tb[__TUNNEL_ATTR_MAX];
+ struct blob_attr *cur;
+ struct ip_tunnel_parm p;
+ const char *base, *str;
+ bool is_sit;
+
+ system_del_ip_tunnel(name);
+
+ tunnel_parm_init(&p);
+
+ blobmsg_parse(tunnel_attr_list.params, __TUNNEL_ATTR_MAX, tb,
+ blob_data(attr), blob_len(attr));
+
+ if (!(cur = tb[TUNNEL_ATTR_TYPE]))
+ return -EINVAL;
+ str = blobmsg_data(cur);
+ is_sit = !strcmp(str, "sit");
+
+ if (is_sit) {
+ p.iph.protocol = IPPROTO_IPV6;
+ base = "sit0";
+ } else
+ return -EINVAL;
+
+ if (!parse_ipaddr(tb[TUNNEL_ATTR_LOCAL], &p.iph.saddr))
+ return -EINVAL;
+
+ if (!parse_ipaddr(tb[TUNNEL_ATTR_REMOTE], &p.iph.daddr))
+ return -EINVAL;
+
+ if ((cur = tb[TUNNEL_ATTR_TTL])) {
+ unsigned int val = blobmsg_get_u32(cur);
+
+ if (val > 255)
+ return -EINVAL;
+
+ p.iph.ttl = val;
+ }
+
+ strncpy(p.name, name, sizeof(p.name));
+ if (tunnel_ioctl(base, SIOCADDTUNNEL, &p) < 0)
+ return -1;
+
+#ifdef SIOCADD6RD
+ cur = tb[TUNNEL_ATTR_6RD_PREFIX];
+ if (cur && is_sit) {
+ unsigned int mask;
+ struct ip_tunnel_6rd p6;
+
+ memset(&p6, 0, sizeof(p6));
+
+ if (!parse_ip_and_netmask(AF_INET6, blobmsg_data(cur),
+ &p6.prefix, &mask) || mask > 128)
+ return -EINVAL;
+ p6.prefixlen = mask;
+
+ if ((cur = tb[TUNNEL_ATTR_6RD_RELAY_PREFIX])) {
+ if (!parse_ip_and_netmask(AF_INET, blobmsg_data(cur),
+ &p6.relay_prefix, &mask) || mask > 32)
+ return -EINVAL;
+ p6.relay_prefixlen = mask;
+ }
+
+ if (tunnel_ioctl(name, SIOCADD6RD, &p6) < 0) {
+ system_del_ip_tunnel(name);
+ return -1;
+ }
+ }
+#endif
+
+ return 0;
+}