-static int router_icmpv6_valid(struct sockaddr_in6 *source, uint8_t *data, size_t len)
-{
- struct icmp6_hdr *hdr = (struct icmp6_hdr *)data;
- struct icmpv6_opt *opt;
- size_t optlen = len - sizeof(*hdr);
-
- /* Hoplimit is already checked in odhcpd_receive_packets */
- if (len < sizeof(*hdr))
- return 0;
-
- if (hdr->icmp6_code)
- return 0;
-
- switch (hdr->icmp6_type) {
- case ND_ROUTER_ADVERT:
- if (!IN6_IS_ADDR_LINKLOCAL(&source->sin6_addr))
- return 0;
-
- opt = (struct icmpv6_opt *)((struct nd_router_advert *)data + 1);
- break;
-
- case ND_ROUTER_SOLICIT:
- opt = (struct icmpv6_opt *)((struct nd_router_solicit *)data + 1);
- break;
-
- default:
- return 0;
- }
-
- while (optlen > 0) {
- size_t l = opt->len << 3;
-
- if (optlen < sizeof(*opt))
- return 0;
-
- if (l > optlen || l == 0)
- return 0;
-
- if (opt->type == ND_OPT_SOURCE_LINKADDR && IN6_IS_ADDR_UNSPECIFIED(&source->sin6_addr) &&
- hdr->icmp6_type == ND_ROUTER_SOLICIT) {
- return 0;
- }
-
- opt = (struct icmpv6_opt *)(((uint8_t *)opt) + l);
-
- optlen -= l;
- }
-
- return 1;
-}