rtsol.tproj/rtsol.c

   1 /*      $KAME: rtsol.c,v 1.11 2000/08/13 06:14:59 itojun Exp $  */
   2
   3 /*
   4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the project nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  * $FreeBSD: src/usr.sbin/rtsold/rtsol.c,v 1.1.2.3 2001/07/03 11:02:16 ume Exp $
  32  */
  33
  34 #include <sys/param.h>
  35 #include <sys/socket.h>
  36 #include <sys/uio.h>
  37 #include <sys/time.h>
  38 #include <sys/queue.h>
  39
  40 #include <net/if.h>
  41 #include <net/route.h>
  42 #include <net/if_dl.h>
  43
  44 #include <netinet/in.h>
  45 #include <netinet/ip6.h>
  46 #include <netinet6/ip6_var.h>
  47 #include <netinet/icmp6.h>
  48
  49 #include <arpa/inet.h>
  50
  51 #include <time.h>
  52 #include <unistd.h>
  53 #include <stdio.h>
  54 #include <err.h>
  55 #include <errno.h>
  56 #include <string.h>
  57 #include <stdlib.h>
  58 #include <syslog.h>
  59 #include "rtsold.h"
  60
  61 #define ALLROUTER "ff02::2"
  62
  63 static struct msghdr rcvmhdr;
  64 static struct msghdr sndmhdr;
  65 static struct iovec rcviov[2];
  66 static struct iovec sndiov[2];
  67 static struct sockaddr_in6 from;
  68
  69 int rssock;
  70
  71 static struct sockaddr_in6 sin6_allrouters = {sizeof(sin6_allrouters), AF_INET6};
  72
  73 int
  74 sockopen()
  75 {
  76         int on;
  77         struct icmp6_filter filt;
  78         static u_char answer[1500];
  79         int rcvcmsglen, sndcmsglen;
  80         static u_char *rcvcmsgbuf = NULL, *sndcmsgbuf = NULL;
  81
  82         sndcmsglen = rcvcmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo)) +
  83                 CMSG_SPACE(sizeof(int));
  84         if (rcvcmsgbuf == NULL && (rcvcmsgbuf = malloc(rcvcmsglen)) == NULL) {
  85                 warnmsg(LOG_ERR, __FUNCTION__,
  86                         "malloc for receive msghdr failed");
  87                 return(-1);
  88         }
  89         if (sndcmsgbuf == NULL && (sndcmsgbuf = malloc(sndcmsglen)) == NULL) {
  90                 warnmsg(LOG_ERR, __FUNCTION__,
  91                         "malloc for send msghdr failed");
  92                 return(-1);
  93         }
  94         memset(&sin6_allrouters, 0, sizeof(struct sockaddr_in6));
  95         if (inet_pton(AF_INET6, ALLROUTER,
  96                       &sin6_allrouters.sin6_addr.s6_addr) != 1) {
  97                 warnmsg(LOG_ERR, __FUNCTION__, "inet_pton failed for %s",
  98                        ALLROUTER);
  99                 return(-1);
 100         }
 101
 102         if ((rssock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) {
 103                 warnmsg(LOG_ERR, __FUNCTION__, "socket: %s", strerror(errno));
 104                 return(-1);
 105         }
 106
 107         /* specify to tell receiving interface */
 108         on = 1;
 109 #ifdef IPV6_RECVPKTINFO
 110         if (setsockopt(rssock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
 111                        sizeof(on)) < 0) {
 112                 warnmsg(LOG_ERR, __FUNCTION__, "IPV6_RECVPKTINFO: %s",
 113                        strerror(errno));
 114                 exit(1);
 115         }
 116 #else  /* old adv. API */
 117         if (setsockopt(rssock, IPPROTO_IPV6, IPV6_PKTINFO, &on,
 118                        sizeof(on)) < 0) {
 119                 warnmsg(LOG_ERR, __FUNCTION__, "IPV6_PKTINFO: %s",
 120                        strerror(errno));
 121                 exit(1);
 122         }
 123 #endif
 124
 125         on = 1;
 126         /* specify to tell value of hoplimit field of received IP6 hdr */
 127 #ifdef IPV6_RECVHOPLIMIT
 128         if (setsockopt(rssock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
 129                        sizeof(on)) < 0) {
 130                 warnmsg(LOG_ERR, __FUNCTION__, "IPV6_RECVHOPLIMIT: %s",
 131                        strerror(errno));
 132                 exit(1);
 133         }
 134 #else  /* old adv. API */
 135         if (setsockopt(rssock, IPPROTO_IPV6, IPV6_HOPLIMIT, &on,
 136                        sizeof(on)) < 0) {
 137                 warnmsg(LOG_ERR, __FUNCTION__, "IPV6_HOPLIMIT: %s",
 138                        strerror(errno));
 139                 exit(1);
 140         }
 141 #endif
 142
 143         /* specfiy to accept only router advertisements on the socket */
 144         ICMP6_FILTER_SETBLOCKALL(&filt);
 145         ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt);
 146         if (setsockopt(rssock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
 147                        sizeof(filt)) == -1) {
 148                 warnmsg(LOG_ERR, __FUNCTION__, "setsockopt(ICMP6_FILTER): %s",
 149                        strerror(errno));
 150                 return(-1);
 151         }
 152
 153         /* initialize msghdr for receiving packets */
 154         rcviov[0].iov_base = (caddr_t)answer;
 155         rcviov[0].iov_len = sizeof(answer);
 156         rcvmhdr.msg_name = (caddr_t)&from;
 157         rcvmhdr.msg_namelen = sizeof(from);
 158         rcvmhdr.msg_iov = rcviov;
 159         rcvmhdr.msg_iovlen = 1;
 160         rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
 161         rcvmhdr.msg_controllen = rcvcmsglen;
 162
 163         /* initialize msghdr for sending packets */
 164         sndmhdr.msg_namelen = sizeof(struct sockaddr_in6);
 165         sndmhdr.msg_iov = sndiov;
 166         sndmhdr.msg_iovlen = 1;
 167         sndmhdr.msg_control = (caddr_t)sndcmsgbuf;
 168         sndmhdr.msg_controllen = sndcmsglen;
 169
 170         return(rssock);
 171 }
 172
 173 void
 174 sendpacket(struct ifinfo *ifinfo)
 175 {
 176         int i;
 177         struct cmsghdr *cm;
 178         struct in6_pktinfo *pi;
 179
 180         sndmhdr.msg_name = (caddr_t)&sin6_allrouters;
 181         sndmhdr.msg_iov[0].iov_base = (caddr_t)ifinfo->rs_data;
 182         sndmhdr.msg_iov[0].iov_len = ifinfo->rs_datalen;
 183
 184         cm = CMSG_FIRSTHDR(&sndmhdr);
 185         /* specify the outgoing interface */
 186         cm->cmsg_level = IPPROTO_IPV6;
 187         cm->cmsg_type = IPV6_PKTINFO;
 188         cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
 189         pi = (struct in6_pktinfo *)CMSG_DATA(cm);
 190         memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr));       /*XXX*/
 191         pi->ipi6_ifindex = ifinfo->sdl->sdl_index;
 192
 193         /* specify the hop limit of the packet */
 194         {
 195                 int hoplimit = 255;
 196
 197                 cm = CMSG_NXTHDR(&sndmhdr, cm);
 198                 cm->cmsg_level = IPPROTO_IPV6;
 199                 cm->cmsg_type = IPV6_HOPLIMIT;
 200                 cm->cmsg_len = CMSG_LEN(sizeof(int));
 201                 memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int));
 202         }
 203
 204         warnmsg(LOG_DEBUG,
 205                __FUNCTION__, "send RS on %s, whose state is %d",
 206                ifinfo->ifname, ifinfo->state);
 207
 208         i = sendmsg(rssock, &sndmhdr, 0);
 209
 210         if (i < 0 || i != ifinfo->rs_datalen) {
 211                 /*
 212                  * ENETDOWN is not so serious, especially when using several
 213                  * network cards on a mobile node. We ignore it.
 214                  */
 215                 if (errno != ENETDOWN || dflag > 0)
 216                         warnmsg(LOG_ERR, __FUNCTION__, "sendmsg on %s: %s",
 217                                 ifinfo->ifname, strerror(errno));
 218         }
 219
 220         /* update counter */
 221         ifinfo->probes++;
 222 }
 223
 224 void
 225 rtsol_input(int s)
 226 {
 227         int i;
 228         int *hlimp = NULL;
 229         struct icmp6_hdr *icp;
 230         int ifindex = 0;
 231         struct cmsghdr *cm;
 232         struct in6_pktinfo *pi = NULL;
 233         struct ifinfo *ifi = NULL;
 234         u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
 235
 236         /* get message */
 237         if ((i = recvmsg(s, &rcvmhdr, 0)) < 0) {
 238                 warnmsg(LOG_ERR, __FUNCTION__, "recvmsg: %s", strerror(errno));
 239                 return;
 240         }
 241
 242         /* extract optional information via Advanced API */
 243         for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhdr);
 244              cm;
 245              cm = (struct cmsghdr *)CMSG_NXTHDR(&rcvmhdr, cm)) {
 246                 if (cm->cmsg_level == IPPROTO_IPV6 &&
 247                     cm->cmsg_type == IPV6_PKTINFO &&
 248                     cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) {
 249                         pi = (struct in6_pktinfo *)(CMSG_DATA(cm));
 250                         ifindex = pi->ipi6_ifindex;
 251                 }
 252                 if (cm->cmsg_level == IPPROTO_IPV6 &&
 253                     cm->cmsg_type == IPV6_HOPLIMIT &&
 254                     cm->cmsg_len == CMSG_LEN(sizeof(int)))
 255                         hlimp = (int *)CMSG_DATA(cm);
 256         }
 257
 258         if (ifindex == 0) {
 259                 warnmsg(LOG_ERR,
 260                        __FUNCTION__, "failed to get receiving interface");
 261                 return;
 262         }
 263         if (hlimp == NULL) {
 264                 warnmsg(LOG_ERR,
 265                        __FUNCTION__, "failed to get receiving hop limit");
 266                 return;
 267         }
 268
 269         if (i < sizeof(struct nd_router_advert)) {
 270                 warnmsg(LOG_ERR,
 271                        __FUNCTION__, "packet size(%d) is too short", i);
 272                 return;
 273         }
 274
 275         icp = (struct icmp6_hdr *)rcvmhdr.msg_iov[0].iov_base;
 276
 277         if (icp->icmp6_type != ND_ROUTER_ADVERT) {
 278                 warnmsg(LOG_ERR, __FUNCTION__,
 279                         "invalid icmp type(%d) from %s on %s", icp->icmp6_type,
 280                        inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 281                                  INET6_ADDRSTRLEN),
 282                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 283                 return;
 284         }
 285
 286         if (icp->icmp6_code != 0) {
 287                 warnmsg(LOG_ERR, __FUNCTION__,
 288                         "invalid icmp code(%d) from %s on %s", icp->icmp6_code,
 289                        inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 290                                  INET6_ADDRSTRLEN),
 291                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 292                 return;
 293         }
 294
 295         if (*hlimp != 255) {
 296                 warnmsg(LOG_NOTICE, __FUNCTION__,
 297                         "invalid RA with hop limit(%d) from %s on %s",
 298                        *hlimp,
 299                        inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 300                                  INET6_ADDRSTRLEN),
 301                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 302                 return;
 303         }
 304
 305         if (pi && !IN6_IS_ADDR_LINKLOCAL(&from.sin6_addr)) {
 306                 warnmsg(LOG_NOTICE, __FUNCTION__,
 307                         "invalid RA with non link-local source from %s on %s",
 308                        inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 309                                  INET6_ADDRSTRLEN),
 310                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 311                 return;
 312         }
 313
 314         /* xxx: more validation? */
 315
 316         if ((ifi = find_ifinfo(pi->ipi6_ifindex)) == NULL) {
 317                 warnmsg(LOG_NOTICE, __FUNCTION__,
 318                         "received RA from %s on an unexpeced IF(%s)",
 319                        inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 320                                  INET6_ADDRSTRLEN),
 321                        if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 322                 return;
 323         }
 324
 325         warnmsg(LOG_DEBUG, __FUNCTION__,
 326                 "received RA from %s on %s, state is %d",
 327                inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
 328                          INET6_ADDRSTRLEN),
 329                ifi->ifname, ifi->state);
 330
 331         ifi->racnt++;
 332
 333         switch(ifi->state) {
 334          case IFS_IDLE:         /* should be ignored */
 335          case IFS_DELAY:                /* right? */
 336                  break;
 337          case IFS_PROBE:
 338                  ifi->state = IFS_IDLE;
 339                  ifi->probes = 0;
 340                  rtsol_timer_update(ifi);
 341                  break;
 342         }
 343 }