/**
- * 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 <netinet/in.h>
#include <netinet/icmp6.h>
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