mld6.c revision 1.6.2.1
1 /* $NetBSD: mld6.c,v 1.6.2.1 2000/11/20 18:10:56 bouyer Exp $ */ 2 /* $KAME: mld6.c,v 1.16 2000/02/22 14:04:27 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1988 Stephen Deering. 35 * Copyright (c) 1992, 1993 36 * The Regents of the University of California. All rights reserved. 37 * 38 * This code is derived from software contributed to Berkeley by 39 * Stephen Deering of Stanford University. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 3. All advertising materials mentioning features or use of this software 50 * must display the following acknowledgement: 51 * This product includes software developed by the University of 52 * California, Berkeley and its contributors. 53 * 4. Neither the name of the University nor the names of its contributors 54 * may be used to endorse or promote products derived from this software 55 * without specific prior written permission. 56 * 57 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 58 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 59 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 60 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 61 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 62 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 63 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 64 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 65 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 66 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 67 * SUCH DAMAGE. 68 * 69 * @(#)igmp.c 8.1 (Berkeley) 7/19/93 70 */ 71 72 #include "opt_inet.h" 73 74 #include <sys/param.h> 75 #include <sys/systm.h> 76 #include <sys/mbuf.h> 77 #include <sys/socket.h> 78 #include <sys/protosw.h> 79 #include <sys/syslog.h> 80 81 #include <net/if.h> 82 83 #include <netinet/in.h> 84 #include <netinet/in_var.h> 85 #include <netinet/ip6.h> 86 #include <netinet6/ip6_var.h> 87 #include <netinet/icmp6.h> 88 #include <netinet6/mld6_var.h> 89 90 #include <net/net_osdep.h> 91 92 /* 93 * Protocol constants 94 */ 95 96 /* denotes that the MLD max response delay field specifies time in milliseconds */ 97 #define MLD6_TIMER_SCALE 1000 98 /* 99 * time between repetitions of a node's initial report of interest in a 100 * multicast address(in seconds) 101 */ 102 #define MLD6_UNSOLICITED_REPORT_INTERVAL 10 103 104 static struct ip6_pktopts ip6_opts; 105 static int mld6_timers_are_running; 106 /* XXX: These are necessary for KAME's link-local hack */ 107 static struct in6_addr mld6_all_nodes_linklocal = IN6ADDR_LINKLOCAL_ALLNODES_INIT; 108 static struct in6_addr mld6_all_routers_linklocal = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT; 109 110 static void mld6_sendpkt __P((struct in6_multi *, int, const struct in6_addr *)); 111 112 void 113 mld6_init() 114 { 115 static u_int8_t hbh_buf[8]; 116 struct ip6_hbh *hbh = (struct ip6_hbh *)hbh_buf; 117 u_int16_t rtalert_code = htons((u_int16_t)IP6OPT_RTALERT_MLD); 118 119 mld6_timers_are_running = 0; 120 121 /* ip6h_nxt will be fill in later */ 122 hbh->ip6h_len = 0; /* (8 >> 3) - 1 */ 123 124 /* XXX: grotty hard coding... */ 125 hbh_buf[2] = IP6OPT_PADN; /* 2 byte padding */ 126 hbh_buf[3] = 0; 127 hbh_buf[4] = IP6OPT_RTALERT; 128 hbh_buf[5] = IP6OPT_RTALERT_LEN - 2; 129 bcopy((caddr_t)&rtalert_code, &hbh_buf[6], sizeof(u_int16_t)); 130 131 ip6_opts.ip6po_hbh = hbh; 132 /* We will specify the hoplimit by a multicast option. */ 133 ip6_opts.ip6po_hlim = -1; 134 } 135 136 void 137 mld6_start_listening(in6m) 138 struct in6_multi *in6m; 139 { 140 int s = splsoftnet(); 141 142 /* 143 * RFC2710 page 10: 144 * The node never sends a Report or Done for the link-scope all-nodes 145 * address. 146 * MLD messages are never sent for multicast addresses whose scope is 0 147 * (reserved) or 1 (node-local). 148 */ 149 mld6_all_nodes_linklocal.s6_addr16[1] = 150 htons(in6m->in6m_ifp->if_index); /* XXX */ 151 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal) || 152 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) { 153 in6m->in6m_timer = 0; 154 in6m->in6m_state = MLD6_OTHERLISTENER; 155 } else { 156 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, NULL); 157 in6m->in6m_timer = MLD6_RANDOM_DELAY( 158 MLD6_UNSOLICITED_REPORT_INTERVAL * PR_FASTHZ); 159 in6m->in6m_state = MLD6_IREPORTEDLAST; 160 mld6_timers_are_running = 1; 161 } 162 splx(s); 163 } 164 165 void 166 mld6_stop_listening(in6m) 167 struct in6_multi *in6m; 168 { 169 mld6_all_nodes_linklocal.s6_addr16[1] = 170 htons(in6m->in6m_ifp->if_index); /* XXX */ 171 mld6_all_routers_linklocal.s6_addr16[1] = 172 htons(in6m->in6m_ifp->if_index); /* XXX: necessary when mrouting */ 173 174 if (in6m->in6m_state == MLD6_IREPORTEDLAST && 175 (!IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal)) && 176 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) > IPV6_ADDR_SCOPE_NODELOCAL) 177 mld6_sendpkt(in6m, MLD6_LISTENER_DONE, 178 &mld6_all_routers_linklocal); 179 } 180 181 void 182 mld6_input(m, off) 183 struct mbuf *m; 184 int off; 185 { 186 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 187 struct mld6_hdr *mldh; 188 struct ifnet *ifp = m->m_pkthdr.rcvif; 189 struct in6_multi *in6m; 190 struct in6_ifaddr *ia; 191 int timer; /* timer value in the MLD query header */ 192 193 /* source address validation */ 194 if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) { 195 log(LOG_ERR, 196 "mld6_input: src %s is not link-local\n", 197 ip6_sprintf(&ip6->ip6_src)); 198 /* 199 * spec (RFC2710) does not explicitly 200 * specify to discard the packet from a non link-local 201 * source address. But we believe it's expected to do so. 202 */ 203 m_freem(m); 204 return; 205 } 206 207 #ifndef PULLDOWN_TEST 208 IP6_EXTHDR_CHECK(m, off, sizeof(*mldh),); 209 mldh = (struct mld6_hdr *)(mtod(m, caddr_t) + off); 210 #else 211 IP6_EXTHDR_GET(mldh, struct mld6_hdr *, m, off, sizeof(*mldh)); 212 if (mldh == NULL) { 213 icmp6stat.icp6s_tooshort++; 214 return; 215 } 216 #endif 217 218 /* 219 * In the MLD6 specification, there are 3 states and a flag. 220 * 221 * In Non-Listener state, we simply don't have a membership record. 222 * In Delaying Listener state, our timer is running (in6m->in6m_timer) 223 * In Idle Listener state, our timer is not running (in6m->in6m_timer==0) 224 * 225 * The flag is in6m->in6m_state, it is set to MLD6_OTHERLISTENER if 226 * we have heard a report from another member, or MLD6_IREPORTEDLAST 227 * if we sent the last report. 228 */ 229 switch(mldh->mld6_type) { 230 case MLD6_LISTENER_QUERY: 231 if (ifp->if_flags & IFF_LOOPBACK) 232 break; 233 234 if (!IN6_IS_ADDR_UNSPECIFIED(&mldh->mld6_addr) && 235 !IN6_IS_ADDR_MULTICAST(&mldh->mld6_addr)) 236 break; /* print error or log stat? */ 237 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 238 mldh->mld6_addr.s6_addr16[1] = 239 htons(ifp->if_index); /* XXX */ 240 241 /* 242 * - Start the timers in all of our membership records 243 * that the query applies to for the interface on 244 * which the query arrived excl. those that belong 245 * to the "all-nodes" group (ff02::1). 246 * - Restart any timer that is already running but has 247 * A value longer than the requested timeout. 248 * - Use the value specified in the query message as 249 * the maximum timeout. 250 */ 251 IFP_TO_IA6(ifp, ia); 252 if (ia == NULL) 253 break; 254 255 /* 256 * XXX: System timer resolution is too low to handle Max 257 * Response Delay, so set 1 to the internal timer even if 258 * the calculated value equals to zero when Max Response 259 * Delay is positive. 260 */ 261 timer = ntohs(mldh->mld6_maxdelay)*PR_FASTHZ/MLD6_TIMER_SCALE; 262 if (timer == 0 && mldh->mld6_maxdelay) 263 timer = 1; 264 mld6_all_nodes_linklocal.s6_addr16[1] = 265 htons(ifp->if_index); /* XXX */ 266 267 for (in6m = ia->ia6_multiaddrs.lh_first; 268 in6m; 269 in6m = in6m->in6m_entry.le_next) 270 { 271 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, 272 &mld6_all_nodes_linklocal) || 273 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < 274 IPV6_ADDR_SCOPE_LINKLOCAL) 275 continue; 276 277 if (IN6_IS_ADDR_UNSPECIFIED(&mldh->mld6_addr) || 278 IN6_ARE_ADDR_EQUAL(&mldh->mld6_addr, 279 &in6m->in6m_addr)) 280 { 281 if (timer == 0) { 282 /* send a report immediately */ 283 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, 284 NULL); 285 in6m->in6m_timer = 0; /* reset timer */ 286 in6m->in6m_state = MLD6_IREPORTEDLAST; 287 } 288 else if (in6m->in6m_timer == 0 || /*idle state*/ 289 in6m->in6m_timer > timer) { 290 in6m->in6m_timer = 291 MLD6_RANDOM_DELAY(timer); 292 mld6_timers_are_running = 1; 293 } 294 } 295 } 296 297 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 298 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 299 break; 300 case MLD6_LISTENER_REPORT: 301 /* 302 * For fast leave to work, we have to know that we are the 303 * last person to send a report for this group. Reports 304 * can potentially get looped back if we are a multicast 305 * router, so discard reports sourced by me. 306 * Note that it is impossible to check IFF_LOOPBACK flag of 307 * ifp for this purpose, since ip6_mloopback pass the physical 308 * interface to looutput. 309 */ 310 if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */ 311 break; 312 313 if (!IN6_IS_ADDR_MULTICAST(&mldh->mld6_addr)) 314 break; 315 316 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 317 mldh->mld6_addr.s6_addr16[1] = 318 htons(ifp->if_index); /* XXX */ 319 /* 320 * If we belong to the group being reported, stop 321 * our timer for that group. 322 */ 323 IN6_LOOKUP_MULTI(mldh->mld6_addr, ifp, in6m); 324 if (in6m) { 325 in6m->in6m_timer = 0; /* transit to idle state */ 326 in6m->in6m_state = MLD6_OTHERLISTENER; /* clear flag */ 327 } 328 329 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 330 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 331 break; 332 default: /* this is impossible */ 333 log(LOG_ERR, "mld6_input: illegal type(%d)", mldh->mld6_type); 334 break; 335 } 336 337 m_freem(m); 338 } 339 340 void 341 mld6_fasttimeo() 342 { 343 register struct in6_multi *in6m; 344 struct in6_multistep step; 345 int s; 346 347 /* 348 * Quick check to see if any work needs to be done, in order 349 * to minimize the overhead of fasttimo processing. 350 */ 351 if (!mld6_timers_are_running) 352 return; 353 354 s = splsoftnet(); 355 mld6_timers_are_running = 0; 356 IN6_FIRST_MULTI(step, in6m); 357 while (in6m != NULL) { 358 if (in6m->in6m_timer == 0) { 359 /* do nothing */ 360 } else if (--in6m->in6m_timer == 0) { 361 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, NULL); 362 in6m->in6m_state = MLD6_IREPORTEDLAST; 363 } else { 364 mld6_timers_are_running = 1; 365 } 366 IN6_NEXT_MULTI(step, in6m); 367 } 368 splx(s); 369 } 370 371 static void 372 mld6_sendpkt(in6m, type, dst) 373 struct in6_multi *in6m; 374 int type; 375 const struct in6_addr *dst; 376 { 377 struct mbuf *mh, *md; 378 struct mld6_hdr *mldh; 379 struct ip6_hdr *ip6; 380 struct ip6_moptions im6o; 381 struct in6_ifaddr *ia; 382 struct ifnet *ifp = in6m->in6m_ifp; 383 struct ifnet *outif = NULL; 384 385 /* 386 * At first, find a link local address on the outgoing interface 387 * to use as the source address of the MLD packet. 388 */ 389 if ((ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST)) 390 == NULL) 391 return; 392 393 /* 394 * Allocate mbufs to store ip6 header and MLD header. 395 * We allocate 2 mbufs and make chain in advance because 396 * it is more convenient when inserting the hop-by-hop option later. 397 */ 398 MGETHDR(mh, M_DONTWAIT, MT_HEADER); 399 if (mh == NULL) 400 return; 401 MGET(md, M_DONTWAIT, MT_DATA); 402 if (md == NULL) { 403 m_free(mh); 404 return; 405 } 406 mh->m_next = md; 407 408 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld6_hdr); 409 mh->m_len = sizeof(struct ip6_hdr); 410 MH_ALIGN(mh, sizeof(struct ip6_hdr)); 411 412 /* fill in the ip6 header */ 413 ip6 = mtod(mh, struct ip6_hdr *); 414 ip6->ip6_flow = 0; 415 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 416 ip6->ip6_vfc |= IPV6_VERSION; 417 /* ip6_plen will be set later */ 418 ip6->ip6_nxt = IPPROTO_ICMPV6; 419 /* ip6_hlim will be set by im6o.im6o_multicast_hlim */ 420 ip6->ip6_src = ia->ia_addr.sin6_addr; 421 ip6->ip6_dst = dst ? *dst : in6m->in6m_addr; 422 423 /* fill in the MLD header */ 424 md->m_len = sizeof(struct mld6_hdr); 425 mldh = mtod(md, struct mld6_hdr *); 426 mldh->mld6_type = type; 427 mldh->mld6_code = 0; 428 mldh->mld6_cksum = 0; 429 /* XXX: we assume the function will not be called for query messages */ 430 mldh->mld6_maxdelay = 0; 431 mldh->mld6_reserved = 0; 432 mldh->mld6_addr = in6m->in6m_addr; 433 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 434 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 435 mldh->mld6_cksum = in6_cksum(mh, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), 436 sizeof(struct mld6_hdr)); 437 438 /* construct multicast option */ 439 bzero(&im6o, sizeof(im6o)); 440 im6o.im6o_multicast_ifp = ifp; 441 im6o.im6o_multicast_hlim = 1; 442 443 /* 444 * Request loopback of the report if we are acting as a multicast 445 * router, so that the process-level routing daemon can hear it. 446 */ 447 im6o.im6o_multicast_loop = (ip6_mrouter != NULL); 448 449 /* increment output statictics */ 450 icmp6stat.icp6s_outhist[type]++; 451 452 ip6_output(mh, &ip6_opts, NULL, 0, &im6o, &outif); 453 if (outif) { 454 icmp6_ifstat_inc(outif, ifs6_out_msg); 455 switch(type) { 456 case MLD6_LISTENER_QUERY: 457 icmp6_ifstat_inc(outif, ifs6_out_mldquery); 458 break; 459 case MLD6_LISTENER_REPORT: 460 icmp6_ifstat_inc(outif, ifs6_out_mldreport); 461 break; 462 case MLD6_LISTENER_DONE: 463 icmp6_ifstat_inc(outif, ifs6_out_mlddone); 464 break; 465 } 466 } 467 } 468
Indexes created Wed Oct 15 03:09:54 GMT 2025