+#ifdef CONFIG_IPV6_SIT_6RD
+ case SIOCADD6RD:
+ case SIOCCHG6RD:
+ case SIOCDEL6RD:
+ err = -EPERM;
+ if (!capable(CAP_NET_ADMIN))
+ goto done;
+
+ err = -EFAULT;
+ if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data,
+ sizeof(ip6rd)))
+ goto done;
+
+ t = netdev_priv(dev);
+
+ if (cmd != SIOCDEL6RD) {
+ struct in6_addr prefix;
+ __be32 relay_prefix;
+
+ err = -EINVAL;
+ if (ip6rd.relay_prefixlen > 32 ||
+ ip6rd.prefixlen + (32 - ip6rd.relay_prefixlen) > 64)
+ goto done;
+
+ ipv6_addr_prefix(&prefix, &ip6rd.prefix,
+ ip6rd.prefixlen);
+ if (!ipv6_addr_equal(&prefix, &ip6rd.prefix))
+ goto done;
+ if (ip6rd.relay_prefixlen)
+ relay_prefix = ip6rd.relay_prefix &
+ htonl(0xffffffffUL <<
+ (32 - ip6rd.relay_prefixlen));
+ else
+ relay_prefix = 0;
+ if (relay_prefix != ip6rd.relay_prefix)
+ goto done;
+
+ ipv6_addr_copy(&t->ip6rd.prefix, &prefix);
+ t->ip6rd.relay_prefix = relay_prefix;
+ t->ip6rd.prefixlen = ip6rd.prefixlen;
+ t->ip6rd.relay_prefixlen = ip6rd.relay_prefixlen;
+ } else
+ ipip6_tunnel_clone_6rd(dev, sitn);
+
+ err = 0;
+ break;
+#endif
+