1 /* $KAME$ */ 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 * $FreeBSD$ 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 } 344