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