X-Git-Url: https://git.decadent.org.uk/gitweb/?a=blobdiff_plain;f=src%2Fra.c;h=9c1ed74d4ee4e89b90702ae8f33554ff34706bff;hb=9c409ef5ce654ed5dd3ce706317eaac718a22983;hp=b249288279955446ecf59e061a4015b0314b3302;hpb=2ce1c6dcec4afa1c7bd16e79cfcae247b88450ec;p=odhcp6c.git diff --git a/src/ra.c b/src/ra.c index b249288..9c1ed74 100644 --- a/src/ra.c +++ b/src/ra.c @@ -1,12 +1,28 @@ +/** + * Copyright (C) 2012-2013 Steven Barth + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License v2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + #include #include #include #include #include #include +#include #include #include +#include #include #include #include @@ -18,7 +34,7 @@ #include "ra.h" -static int sock = -1, rtnl_sock = -1; +static int sock = -1; static unsigned if_index = 0; static char if_name[IF_NAMESIZE] = {0}; static volatile int rs_attempt = 0; @@ -26,11 +42,12 @@ static struct in6_addr lladdr = IN6ADDR_ANY_INIT; static void ra_send_rs(int signal __attribute__((unused))); -int ra_init(const char *ifname) +int ra_init(const char *ifname, const struct in6_addr *ifid) { sock = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_ICMPV6); if_index = if_nametoindex(ifname); strncpy(if_name, ifname, sizeof(if_name) - 1); + lladdr = *ifid; // Filter ICMPv6 package types struct icmp6_filter filt; @@ -58,31 +75,21 @@ int ra_init(const char *ifname) fcntl(sock, F_SETOWN, ourpid); fcntl(sock, F_SETFL, fcntl(sock, F_GETFL) | O_ASYNC); - // Get LL-addr - FILE *fp = fopen("/proc/net/if_inet6", "r"); - if (fp) { - char addrbuf[33], ifbuf[16]; - while (fscanf(fp, "%32s %*x %*x %*x %*x %15s", addrbuf, ifbuf) == 2) { - if (!strcmp(ifbuf, if_name)) { - script_unhexlify((uint8_t*)&lladdr, sizeof(lladdr), addrbuf); - break; + if (IN6_IS_ADDR_UNSPECIFIED(&lladdr)) { + // Autodetect interface-id if not specified + FILE *fp = fopen("/proc/net/if_inet6", "r"); + if (fp) { + char addrbuf[33], ifbuf[16]; + while (fscanf(fp, "%32s %*x %*x %*x %*x %15s", addrbuf, ifbuf) == 2) { + if (!strcmp(ifbuf, if_name)) { + script_unhexlify((uint8_t*)&lladdr, sizeof(lladdr), addrbuf); + break; + } } + fclose(fp); } - fclose(fp); } - // Open rtnetlink socket - rtnl_sock = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, NETLINK_ROUTE); - struct sockaddr_nl rtnl_kernel = { .nl_family = AF_NETLINK }; - if (connect(rtnl_sock, (struct sockaddr*)&rtnl_kernel, sizeof(rtnl_kernel))) - return -1; - uint32_t group = RTNLGRP_IPV6_IFADDR; - setsockopt(rtnl_sock, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &group, sizeof(group)); - - // Add async-mode - fcntl(rtnl_sock, F_SETOWN, ourpid); - fcntl(rtnl_sock, F_SETFL, fcntl(rtnl_sock, F_GETFL) | O_ASYNC); - // Send RS signal(SIGALRM, ra_send_rs); ra_send_rs(SIGALRM); @@ -121,61 +128,13 @@ static void update_proc(const char *sect, const char *opt, uint32_t value) } -static bool ra_deduplicate(const struct in6_addr *any, uint8_t length) -{ - struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, length, 0, *any, 0, 0}; - struct odhcp6c_entry *x = odhcp6c_find_entry(STATE_RA_PREFIX, &entry); - if (x && IN6_ARE_ADDR_EQUAL(&x->target, any)) { - odhcp6c_random(&x->target.s6_addr32[2], 2 * sizeof(uint32_t)); - } else if (odhcp6c_find_entry(STATE_IA_NA, &entry)) { - dhcpv6_request(DHCPV6_MSG_DECLINE); - raise(SIGUSR2); - } - - return !!x; -} - - -bool ra_rtnl_process(void) -{ - bool found = false; - uint8_t buf[8192]; - while (true) { - ssize_t len = recv(rtnl_sock, buf, sizeof(buf), MSG_DONTWAIT); - if (len < 0) - break; - - for (struct nlmsghdr *nh = (struct nlmsghdr*)buf; NLMSG_OK(nh, (size_t)len); - nh = NLMSG_NEXT(nh, len)) { - struct ifaddrmsg *ifa = NLMSG_DATA(nh); - struct in6_addr *addr = NULL; - if (NLMSG_PAYLOAD(nh, 0) < sizeof(*ifa) || ifa->ifa_index != if_index || - (nh->nlmsg_type == RTM_NEWADDR && !(ifa->ifa_flags & IFA_F_DADFAILED)) || - (nh->nlmsg_type == RTM_DELADDR && !(ifa->ifa_flags & IFA_F_TENTATIVE))) - continue; - - ssize_t alen = NLMSG_PAYLOAD(nh, sizeof(*ifa)); - for (struct rtattr *rta = (struct rtattr*)&ifa[1]; RTA_OK(rta, alen); - rta = RTA_NEXT(rta, alen)) - if (rta->rta_type == IFA_ADDRESS && RTA_PAYLOAD(rta) >= sizeof(*addr)) - addr = RTA_DATA(rta); - - if (addr) - found |= ra_deduplicate(addr, ifa->ifa_prefixlen); - } - } - return found; -} - - bool ra_process(void) { bool found = false; uint8_t buf[1500]; struct nd_router_advert *adv = (struct nd_router_advert*)buf; - struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, 0, 0, IN6ADDR_ANY_INIT, 0, 0}; + struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, 0, 0, IN6ADDR_ANY_INIT, 0, 0, 0}; const struct in6_addr any = IN6ADDR_ANY_INIT; - odhcp6c_expire(); while (true) { struct sockaddr_in6 from; @@ -192,10 +151,15 @@ bool ra_process(void) rs_attempt = 0; } - found = true; + if (!found) { + odhcp6c_expire(); + found = true; + } uint32_t router_valid = ntohs(adv->nd_ra_router_lifetime); // Parse default route + entry.target = any; + entry.length = 0; entry.router = from.sin6_addr; entry.priority = pref_to_priority(adv->nd_ra_flags_reserved); if (entry.priority < 0) @@ -205,10 +169,10 @@ bool ra_process(void) odhcp6c_update_entry(STATE_RA_ROUTE, &entry); // Parse ND parameters - if (adv->nd_ra_reachable) + if (ntohl(adv->nd_ra_reachable) <= 3600000) update_proc("neigh", "base_reachable_time_ms", ntohl(adv->nd_ra_reachable)); - if (adv->nd_ra_retransmit) + if (ntohl(adv->nd_ra_retransmit) <= 60000) update_proc("neigh", "retrans_time_ms", ntohl(adv->nd_ra_retransmit)); @@ -216,13 +180,16 @@ bool ra_process(void) struct icmpv6_opt *opt; icmpv6_for_each_option(opt, &adv[1], &buf[len]) { if (opt->type == ND_OPT_MTU) { - update_proc("conf", "mtu", ntohl(*((uint32_t*)&opt->data[2]))); + 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) { entry.router = from.sin6_addr; entry.target = any; entry.priority = pref_to_priority(opt->data[1]); entry.length = opt->data[0]; - entry.valid = ntohl(*((uint32_t*)&opt->data[2])); + 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) @@ -236,7 +203,7 @@ bool ra_process(void) struct nd_opt_prefix_info *pinfo = (struct nd_opt_prefix_info*)opt; entry.router = any; entry.target = pinfo->nd_opt_pi_prefix; - entry.priority = 0; + entry.priority = 256; entry.length = pinfo->nd_opt_pi_prefix_len; entry.valid = ntohl(pinfo->nd_opt_pi_valid_time); entry.preferred = ntohl(pinfo->nd_opt_pi_preferred_time); @@ -262,7 +229,8 @@ bool ra_process(void) entry.router = from.sin6_addr; entry.priority = 0; entry.length = 128; - entry.valid = ntohl(*((uint32_t*)&opt->data[2])); + 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) { @@ -281,6 +249,8 @@ bool ra_process(void) entry[i].valid = router_valid; } - odhcp6c_expire(); + if (found) + odhcp6c_expire(); + return found; }