1 /* $KAME: probe.c,v 1.17 2003/10/05 00:09:36 itojun Exp $ */
4 * SPDX-License-Identifier: BSD-3-Clause
6 * Copyright (C) 1998 WIDE Project.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the project nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 #include <sys/param.h>
37 #include <sys/types.h>
38 #include <sys/ioctl.h>
39 #include <sys/socket.h>
40 #include <sys/sysctl.h>
42 #include <sys/queue.h>
45 #include <net/if_dl.h>
47 #include <netinet/in.h>
48 #include <netinet6/in6_var.h>
49 #include <netinet/icmp6.h>
50 #include <netinet6/nd6.h>
52 #include <arpa/inet.h>
62 static struct msghdr sndmhdr;
63 static struct iovec sndiov[2];
65 static void sendprobe(struct in6_addr *, struct ifinfo *);
70 int scmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
71 CMSG_SPACE(sizeof(int));
72 static u_char *sndcmsgbuf = NULL;
74 if (sndcmsgbuf == NULL &&
75 (sndcmsgbuf = (u_char *)malloc(scmsglen)) == NULL) {
76 warnmsg(LOG_ERR, __func__, "malloc failed");
80 if ((probesock = socket(AF_INET6, SOCK_RAW, IPPROTO_NONE)) < 0) {
81 warnmsg(LOG_ERR, __func__, "socket: %s", strerror(errno));
85 /* initialize msghdr for sending packets */
86 sndmhdr.msg_namelen = sizeof(struct sockaddr_in6);
87 sndmhdr.msg_iov = sndiov;
88 sndmhdr.msg_iovlen = 1;
89 sndmhdr.msg_control = (caddr_t)sndcmsgbuf;
90 sndmhdr.msg_controllen = scmsglen;
96 * Probe if each router in the default router list is still alive.
99 defrouter_probe(struct ifinfo *ifinfo)
101 struct in6_defrouter *p, *ep;
103 char *buf, ntopbuf[INET6_ADDRSTRLEN];
106 ifindex = ifinfo->sdl->sdl_index;
111 mib[2] = IPPROTO_ICMPV6;
112 mib[3] = ICMPV6CTL_ND6_DRLIST;
113 if (sysctl(mib, nitems(mib), NULL, &l, NULL, 0) < 0) {
114 warnmsg(LOG_ERR, __func__, "sysctl(ICMPV6CTL_ND6_DRLIST): %s",
122 warnmsg(LOG_ERR, __func__, "malloc(): %s", strerror(errno));
125 if (sysctl(mib, nitems(mib), buf, &l, NULL, 0) < 0) {
126 warnmsg(LOG_ERR, __func__, "sysctl(ICMPV6CTL_ND6_DRLIST): %s",
131 ep = (struct in6_defrouter *)(void *)(buf + l);
132 for (p = (struct in6_defrouter *)(void *)buf; p < ep; p++) {
133 if (ifindex != p->if_index)
135 if (!IN6_IS_ADDR_LINKLOCAL(&p->rtaddr.sin6_addr)) {
136 warnmsg(LOG_ERR, __func__,
137 "default router list contains a "
138 "non-link-local address(%s)",
139 inet_ntop(AF_INET6, &p->rtaddr.sin6_addr, ntopbuf,
141 continue; /* ignore the address */
143 sendprobe(&p->rtaddr.sin6_addr, ifinfo);
149 sendprobe(struct in6_addr *addr, struct ifinfo *ifinfo)
151 u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
152 struct sockaddr_in6 sa6_probe;
153 struct in6_pktinfo *pi;
155 u_int32_t ifindex = ifinfo->sdl->sdl_index;
158 memset(&sa6_probe, 0, sizeof(sa6_probe));
159 sa6_probe.sin6_family = AF_INET6;
160 sa6_probe.sin6_len = sizeof(sa6_probe);
161 sa6_probe.sin6_addr = *addr;
162 sa6_probe.sin6_scope_id = ifinfo->linkid;
164 sndmhdr.msg_name = (caddr_t)&sa6_probe;
165 sndmhdr.msg_iov[0].iov_base = NULL;
166 sndmhdr.msg_iov[0].iov_len = 0;
168 cm = CMSG_FIRSTHDR(&sndmhdr);
169 /* specify the outgoing interface */
170 cm->cmsg_level = IPPROTO_IPV6;
171 cm->cmsg_type = IPV6_PKTINFO;
172 cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
173 pi = (struct in6_pktinfo *)(void *)CMSG_DATA(cm);
174 memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr)); /*XXX*/
175 pi->ipi6_ifindex = ifindex;
177 /* specify the hop limit of the packet for safety */
178 cm = CMSG_NXTHDR(&sndmhdr, cm);
179 cm->cmsg_level = IPPROTO_IPV6;
180 cm->cmsg_type = IPV6_HOPLIMIT;
181 cm->cmsg_len = CMSG_LEN(sizeof(int));
182 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int));
184 warnmsg(LOG_DEBUG, __func__, "probe a router %s on %s",
185 inet_ntop(AF_INET6, addr, ntopbuf, INET6_ADDRSTRLEN),
186 if_indextoname(ifindex, ifnamebuf));
188 if (sendmsg(probesock, &sndmhdr, 0))
189 warnmsg(LOG_ERR, __func__, "sendmsg on %s: %s",
190 if_indextoname(ifindex, ifnamebuf), strerror(errno));