/**
- * Copyright (C) 2012-2013 Steven Barth <steven@midlink.org>
+ * Copyright (C) 2012-2014 Steven Barth <steven@midlink.org>
*
* 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
*/
#include <fcntl.h>
+#include <ifaddrs.h>
#include <stdio.h>
#include <signal.h>
#include <string.h>
#include <net/if.h>
#include <arpa/inet.h>
#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
#include <netinet/in.h>
#include <netinet/icmp6.h>
static void ra_send_rs(int signal __attribute__((unused)))
{
- const struct icmp6_hdr rs = {ND_ROUTER_SOLICIT, 0, 0, {{0}}};
+ struct {
+ struct icmp6_hdr hdr;
+ struct icmpv6_opt lladdr;
+ } rs = {
+ .hdr = {ND_ROUTER_SOLICIT, 0, 0, {{0}}},
+ .lladdr = {ND_OPT_SOURCE_LINKADDR, 1, {0}},
+ };
const struct sockaddr_in6 dest = {AF_INET6, 0, 0, ALL_IPV6_ROUTERS, if_index};
- sendto(sock, &rs, sizeof(rs), MSG_DONTWAIT, (struct sockaddr*)&dest, sizeof(dest));
+ size_t len = sizeof(rs);
+
+ struct ifreq ifr;
+ memset(&ifr, 0, sizeof(ifr));
+ strncpy(ifr.ifr_name, if_name, sizeof(ifr.ifr_name));
+ if ((rs_attempt % 2 == 0) && !ioctl(sock, SIOCGIFHWADDR, &ifr)
+ && memcmp(rs.lladdr.data, ifr.ifr_hwaddr.sa_data, 6))
+ memcpy(rs.lladdr.data, ifr.ifr_hwaddr.sa_data, 6);
+ else
+ len = sizeof(struct icmp6_hdr);
+
+ sendto(sock, &rs, len, MSG_DONTWAIT, (struct sockaddr*)&dest, sizeof(dest));
if (++rs_attempt <= 3)
alarm(4);
return ret;
}
+static bool 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, *end = (struct icmpv6_opt*)&data[len];
+
+ if (hlim != 255 || len < sizeof(*hdr) || hdr->icmp6_code)
+ return false;
+
+ switch (hdr->icmp6_type) {
+ case ND_ROUTER_ADVERT:
+ if (!IN6_IS_ADDR_LINKLOCAL(&source->sin6_addr))
+ return false;
+
+ opt = (struct icmpv6_opt*)((struct nd_router_advert*)data + 1);
+ break;
+
+ default:
+ return false;
+ }
+
+ icmpv6_for_each_option(opt, opt, end)
+ ;
+
+ return opt == end;
+}
+
bool ra_process(void)
{
bool found = false;
bool changed = false;
+ bool has_lladdr = !IN6_IS_ADDR_UNSPECIFIED(&lladdr);
uint8_t buf[1500], cmsg_buf[128];
struct nd_router_advert *adv = (struct nd_router_advert*)buf;
- struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, 0, 0, IN6ADDR_ANY_INIT, 0, 0, 0, 0, 0};
+ struct odhcp6c_entry entry = {IN6ADDR_ANY_INIT, 0, 0, IN6ADDR_ANY_INIT, 0, 0, 0, 0, 0, 0};
const struct in6_addr any = IN6ADDR_ANY_INIT;
- if (IN6_IS_ADDR_UNSPECIFIED(&lladdr)) {
+ if (!has_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);
+ struct ifaddrs *ifaddr, *ifa;
+
+ if (getifaddrs(&ifaddr) == 0) {
+ for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
+ struct sockaddr_in6 *addr;
+
+ if (ifa->ifa_addr == NULL || ifa->ifa_addr->sa_family != AF_INET6)
+ continue;
+
+ addr = (struct sockaddr_in6*)ifa->ifa_addr;
+
+ if (!IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr))
+ continue;
+
+ if (!strcmp(ifa->ifa_name, if_name)) {
+ lladdr = addr->sin6_addr;
+ has_lladdr = true;
break;
}
}
- fclose(fp);
+
+ freeifaddrs(ifaddr);
}
}
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))
+
+ if (!has_lladdr)
continue;
int hlim = 0;
ch->cmsg_type == IPV6_HOPLIMIT)
memcpy(&hlim, CMSG_DATA(ch), sizeof(hlim));
- if (hlim != 255)
+ if (!ra_icmpv6_valid(&from, hlim, buf, len))
continue;
// Stop sending solicits
entry.preferred = entry.valid;
changed |= odhcp6c_update_entry(STATE_RA_ROUTE, &entry);
+ // Parse hoplimit
+ if (adv->nd_ra_curhoplimit)
+ update_proc("conf", "hop_limit", adv->nd_ra_curhoplimit);
+
// Parse ND parameters
- if (ntohl(adv->nd_ra_reachable) <= 3600000)
- update_proc("neigh", "base_reachable_time_ms", ntohl(adv->nd_ra_reachable));
+ uint32_t reachable = ntohl(adv->nd_ra_reachable);
+ if (reachable > 0 && reachable <= 3600000)
+ update_proc("neigh", "base_reachable_time_ms", reachable);
- if (ntohl(adv->nd_ra_retransmit) <= 60000)
- update_proc("neigh", "retrans_time_ms", ntohl(adv->nd_ra_retransmit));
+ uint32_t retransmit = ntohl(adv->nd_ra_retransmit);
+ if (retransmit > 0 && retransmit <= 60000)
+ update_proc("neigh", "retrans_time_ms", retransmit);
// Evaluate options