diff options
| -rw-r--r-- | src/ra.c | 75 | ||||
| -rw-r--r-- | src/ra.h | 24 |
2 files changed, 20 insertions, 79 deletions
@@ -195,51 +195,6 @@ bool ra_link_up(void) return ret; } -static int ra_icmpv6_valid(struct sockaddr_in6 *source, int hlim, uint8_t *data, size_t len) -{ - struct icmp6_hdr *hdr = (struct icmp6_hdr *)data; - struct icmpv6_opt *opt; - size_t optlen; - - if (hlim != 255) - return 0; - - 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); - optlen = len - sizeof(struct nd_router_advert); - 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; - - opt = (struct icmpv6_opt *)(((uint8_t *)opt) + l); - - optlen -= l; - } - - return 1; -} - bool ra_process(void) { bool found = false; @@ -271,8 +226,10 @@ bool ra_process(void) cmsg_buf, sizeof(cmsg_buf), 0}; ssize_t len = recvmsg(sock, &msg, MSG_DONTWAIT); - if (len <= 0) + if (len < 0) break; + else if (len < (ssize_t)sizeof(*adv)) + continue; int hlim = 0; for (struct cmsghdr *ch = CMSG_FIRSTHDR(&msg); ch != NULL; @@ -281,7 +238,7 @@ bool ra_process(void) ch->cmsg_type == IPV6_HOPLIMIT) memcpy(&hlim, CMSG_DATA(ch), sizeof(hlim)); - if (!ra_icmpv6_valid(&from, hlim, buf, len)) + if (hlim != 255) continue; // Stop sending solicits @@ -323,17 +280,17 @@ bool ra_process(void) struct icmpv6_opt *opt; icmpv6_for_each_option(opt, &adv[1], &buf[len]) { if (opt->type == ND_OPT_MTU) { - struct nd_opt_mtu *mtu = (struct nd_opt_mtu *)opt; - if (ntohl(mtu->nd_opt_mtu_mtu) >= 1280 && ntohl(mtu->nd_opt_mtu_mtu) <= 65535) - update_proc("conf", "mtu", ntohl(mtu->nd_opt_mtu_mtu)); + uint32_t *mtu = (uint32_t*)&opt->data[2]; + if (ntohl(*mtu) >= 1280 && ntohl(*mtu) <= 65535) + update_proc("conf", "mtu", ntohl(*mtu)); } else if (opt->type == ND_OPT_ROUTE_INFORMATION && opt->len <= 3) { - struct nd_opt_route_info *rinfo = (struct nd_opt_route_info *)opt; entry.router = from.sin6_addr; entry.target = any; - entry.priority = pref_to_priority(rinfo->nd_opt_ri_prf); - entry.length = rinfo->nd_opt_ri_prefix_len; - entry.valid = ntohl(rinfo->nd_opt_ri_route_lifetime); - memcpy(&entry.target, &rinfo->nd_opt_ri_prefix[0], (rinfo->nd_opt_ri_len - 1) * 8); + entry.priority = pref_to_priority(opt->data[1]); + entry.length = opt->data[0]; + uint32_t *valid = (uint32_t*)&opt->data[2]; + entry.valid = ntohl(*valid); + memcpy(&entry.target, &opt->data[6], (opt->len - 1) * 8); if (entry.length > 128 || IN6_IS_ADDR_LINKLOCAL(&entry.target) || IN6_IS_ADDR_LOOPBACK(&entry.target) @@ -343,7 +300,7 @@ bool ra_process(void) if (entry.priority > 0) changed |= odhcp6c_update_entry(STATE_RA_ROUTE, &entry); } else if (opt->type == ND_OPT_PREFIX_INFORMATION && opt->len == 4) { - struct nd_opt_prefix_info *pinfo = (struct nd_opt_prefix_info *)opt; + struct nd_opt_prefix_info *pinfo = (struct nd_opt_prefix_info*)opt; entry.router = any; entry.target = pinfo->nd_opt_pi_prefix; entry.priority = 256; @@ -369,15 +326,15 @@ bool ra_process(void) changed |= odhcp6c_update_entry_safe(STATE_RA_PREFIX, &entry, 7200); } else if (opt->type == ND_OPT_RECURSIVE_DNS && opt->len > 2) { - struct nd_opt_recursive_dns *rdns = (struct nd_opt_recursive_dns *)opt; entry.router = from.sin6_addr; entry.priority = 0; entry.length = 128; - entry.valid = ntohl(rdns->lifetime); + uint32_t *valid = (uint32_t*)&opt->data[2]; + entry.valid = ntohl(*valid); entry.preferred = 0; for (ssize_t i = 0; i < (opt->len - 1) / 2; ++i) { - memcpy(&entry.target, &rdns->servers[i], + memcpy(&entry.target, &opt->data[6 + i * sizeof(entry.target)], sizeof(entry.target)); changed |= odhcp6c_update_entry(STATE_RA_DNS, &entry); } @@ -22,32 +22,16 @@ struct icmpv6_opt { uint8_t type; uint8_t len; -}; - -struct nd_opt_recursive_dns { - uint8_t type; - uint8_t len; - uint8_t pad; - uint8_t pad2; - uint32_t lifetime; - struct in6_addr servers[1]; + uint8_t data[6]; }; #define ND_OPT_ROUTE_INFORMATION 24 -struct nd_opt_route_info { - uint8_t nd_opt_ri_type; - uint8_t nd_opt_ri_len; - uint8_t nd_opt_ri_prefix_len; - uint8_t nd_opt_ri_prf; - uint32_t nd_opt_ri_route_lifetime; - uint8_t nd_opt_ri_prefix[1]; -}; + #define icmpv6_for_each_option(opt, start, end)\ for (opt = (struct icmpv6_opt*)(start);\ - ((void *)opt < (void *)end) && \ - (void *)((uint8_t *)opt + (opt->len << 3)) <= (void *)(end); \ - opt = (struct icmpv6_opt *)((uint8_t *)opt + (opt->len << 3))) + (void*)(opt + 1) <= (void*)(end) && opt->len > 0 &&\ + (void*)(opt + opt->len) <= (void*)(end); opt += opt->len) int ra_init(const char *ifname, const struct in6_addr *ifid); |