diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/odhcpd.c | 3 | ||||
| -rw-r--r-- | src/router.c | 76 | ||||
| -rw-r--r-- | src/router.h | 18 |
3 files changed, 77 insertions, 20 deletions
diff --git a/src/odhcpd.c b/src/odhcpd.c index d6ca298..cb84513 100644 --- a/src/odhcpd.c +++ b/src/odhcpd.c @@ -320,8 +320,7 @@ static void odhcpd_receive_packets(struct uloop_fd *u, _unused unsigned int even int *hlim = NULL; struct in6_pktinfo *pktinfo; struct in_pktinfo *pkt4info; - for (struct cmsghdr *ch = CMSG_FIRSTHDR(&msg); ch != NULL && - destiface == 0; ch = CMSG_NXTHDR(&msg, ch)) { + for (struct cmsghdr *ch = CMSG_FIRSTHDR(&msg); ch != NULL; ch = CMSG_NXTHDR(&msg, ch)) { if (ch->cmsg_level == IPPROTO_IPV6 && ch->cmsg_type == IPV6_PKTINFO) { pktinfo = (struct in6_pktinfo*)CMSG_DATA(ch); diff --git a/src/router.c b/src/router.c index 83da938..a213c84 100644 --- a/src/router.c +++ b/src/router.c @@ -130,12 +130,66 @@ static void sigusr1_refresh(_unused int signal) uloop_timeout_set(&iface->timer_rs, 1000); } +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; +} // Event handler for incoming ICMPv6 packets -static void handle_icmpv6(_unused void *addr, void *data, size_t len, +static void handle_icmpv6(void *addr, void *data, size_t len, struct interface *iface) { struct icmp6_hdr *hdr = data; + + if (!router_icmpv6_valid(addr, data, len)) + return; + if ((iface->ra == RELAYD_SERVER && !iface->master)) { // Server mode if (hdr->icmp6_type == ND_ROUTER_SOLICIT) send_router_advert(&iface->timer_rs); @@ -211,7 +265,7 @@ static void send_router_advert(struct uloop_timeout *event) struct { struct nd_router_advert h; - struct icmpv6_opt lladdr; + struct nd_opt_slla lladdr; struct nd_opt_mtu mtu; struct nd_opt_prefix_info prefix[RELAYD_MAX_PREFIXES]; } adv = { @@ -227,7 +281,7 @@ static void send_router_advert(struct uloop_timeout *event) adv.h.nd_ra_flags_reserved |= ND_RA_PREF_LOW; else if (iface->route_preference > 0) adv.h.nd_ra_flags_reserved |= ND_RA_PREF_HIGH; - odhcpd_get_mac(iface, adv.lladdr.data); + odhcpd_get_mac(iface, adv.lladdr.addr); // If not currently shutting down struct odhcpd_ipaddr addrs[RELAYD_MAX_PREFIXES]; @@ -319,14 +373,7 @@ static void send_router_advert(struct uloop_timeout *event) if (!dns_addr) dns_cnt = 0; - struct { - uint8_t type; - uint8_t len; - uint8_t pad; - uint8_t pad2; - uint32_t lifetime; - } dns = {ND_OPT_RECURSIVE_DNS, (1 + (2 * dns_cnt)), 0, 0, htonl(dns_time)}; - + struct nd_opt_recursive_dns dns = {ND_OPT_RECURSIVE_DNS, (1 + (2 * dns_cnt)), 0, 0, htonl(dns_time)}; // DNS Search options @@ -455,11 +502,12 @@ static void forward_router_advertisement(uint8_t *data, size_t len) icmpv6_for_each_option(opt, &adv[1], end) { if (opt->type == ND_OPT_SOURCE_LINKADDR) { // Store address of source MAC-address - mac_ptr = opt->data; + mac_ptr = ((struct nd_opt_slla *)opt)->addr; } else if (opt->type == ND_OPT_RECURSIVE_DNS && opt->len > 1) { + struct nd_opt_recursive_dns *dns = (struct nd_opt_recursive_dns *)opt; // Check if we have to rewrite DNS - dns_ptr = (struct in6_addr*)&opt->data[6]; - dns_count = (opt->len - 1) / 2; + dns_ptr = (struct in6_addr *)&dns[1]; + dns_count = (dns->len - 1) / 2; } } diff --git a/src/router.h b/src/router.h index 1e8649c..8d74967 100644 --- a/src/router.h +++ b/src/router.h @@ -20,15 +20,25 @@ struct icmpv6_opt { uint8_t type; uint8_t len; - uint8_t data[6]; }; +struct nd_opt_slla { + uint8_t type; + uint8_t len; + uint8_t addr[6]; +}; + +struct nd_opt_recursive_dns { + uint8_t type; + uint8_t len; + uint8_t pad; + uint8_t pad2; + uint32_t lifetime; +}; #define icmpv6_for_each_option(opt, start, end)\ for (opt = (struct icmpv6_opt*)(start);\ - (void*)(opt + 1) <= (void*)(end) && opt->len > 0 &&\ - (void*)(opt + opt->len) <= (void*)(end); opt += opt->len) - + (void*)(opt + (opt->len << 3)) <= (void*)(end); opt += (opt->len << 3)) #define MaxRtrAdvInterval 600 #define MinRtrAdvInterval (MaxRtrAdvInterval / 3) |