mld6.c revision 1.25
1 /* $NetBSD: mld6.c,v 1.25 2003/08/22 21:53:09 itojun Exp $ */ 2 /* $KAME: mld6.c,v 1.25 2001/01/16 14:14:18 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) 1992, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * This code is derived from software contributed to Berkeley by 38 * Stephen Deering of Stanford University. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. Neither the name of the University nor the names of its contributors 49 * may be used to endorse or promote products derived from this software 50 * without specific prior written permission. 51 * 52 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 55 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 62 * SUCH DAMAGE. 63 * 64 * @(#)igmp.c 8.1 (Berkeley) 7/19/93 65 */ 66 67 /* 68 * Copyright (c) 1988 Stephen Deering. 69 * 70 * This code is derived from software contributed to Berkeley by 71 * Stephen Deering of Stanford University. 72 * 73 * Redistribution and use in source and binary forms, with or without 74 * modification, are permitted provided that the following conditions 75 * are met: 76 * 1. Redistributions of source code must retain the above copyright 77 * notice, this list of conditions and the following disclaimer. 78 * 2. Redistributions in binary form must reproduce the above copyright 79 * notice, this list of conditions and the following disclaimer in the 80 * documentation and/or other materials provided with the distribution. 81 * 3. All advertising materials mentioning features or use of this software 82 * must display the following acknowledgement: 83 * This product includes software developed by the University of 84 * California, Berkeley and its contributors. 85 * 4. Neither the name of the University nor the names of its contributors 86 * may be used to endorse or promote products derived from this software 87 * without specific prior written permission. 88 * 89 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 90 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 91 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 92 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 93 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 94 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 95 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 96 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 97 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 98 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 99 * SUCH DAMAGE. 100 * 101 * @(#)igmp.c 8.1 (Berkeley) 7/19/93 102 */ 103 104 #include <sys/cdefs.h> 105 __KERNEL_RCSID(0, "$NetBSD: mld6.c,v 1.25 2003/08/22 21:53:09 itojun Exp $"); 106 107 #include "opt_inet.h" 108 109 #include <sys/param.h> 110 #include <sys/systm.h> 111 #include <sys/mbuf.h> 112 #include <sys/socket.h> 113 #include <sys/protosw.h> 114 #include <sys/syslog.h> 115 116 #include <net/if.h> 117 118 #include <netinet/in.h> 119 #include <netinet/in_var.h> 120 #include <netinet/ip6.h> 121 #include <netinet6/ip6_var.h> 122 #include <netinet/icmp6.h> 123 #include <netinet6/mld6_var.h> 124 125 #include <net/net_osdep.h> 126 127 /* 128 * Protocol constants 129 */ 130 131 /* denotes that the MLD max response delay field specifies time in milliseconds */ 132 #define MLD_TIMER_SCALE 1000 133 /* 134 * time between repetitions of a node's initial report of interest in a 135 * multicast address(in seconds) 136 */ 137 #define MLD_UNSOLICITED_REPORT_INTERVAL 10 138 139 static struct ip6_pktopts ip6_opts; 140 static int mld_timers_are_running; 141 /* XXX: These are necessary for KAME's link-local hack */ 142 static struct in6_addr mld_all_nodes_linklocal = IN6ADDR_LINKLOCAL_ALLNODES_INIT; 143 static struct in6_addr mld_all_routers_linklocal = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT; 144 145 static void mld6_sendpkt __P((struct in6_multi *, int, const struct in6_addr *)); 146 147 void 148 mld6_init() 149 { 150 static u_int8_t hbh_buf[8]; 151 struct ip6_hbh *hbh = (struct ip6_hbh *)hbh_buf; 152 u_int16_t rtalert_code = htons((u_int16_t)IP6OPT_RTALERT_MLD); 153 154 mld_timers_are_running = 0; 155 156 /* ip6h_nxt will be fill in later */ 157 hbh->ip6h_len = 0; /* (8 >> 3) - 1 */ 158 159 /* XXX: grotty hard coding... */ 160 hbh_buf[2] = IP6OPT_PADN; /* 2 byte padding */ 161 hbh_buf[3] = 0; 162 hbh_buf[4] = IP6OPT_RTALERT; 163 hbh_buf[5] = IP6OPT_RTALERT_LEN - 2; 164 bcopy((caddr_t)&rtalert_code, &hbh_buf[6], sizeof(u_int16_t)); 165 166 ip6_opts.ip6po_hbh = hbh; 167 /* We will specify the hoplimit by a multicast option. */ 168 ip6_opts.ip6po_hlim = -1; 169 } 170 171 void 172 mld6_start_listening(in6m) 173 struct in6_multi *in6m; 174 { 175 int s = splsoftnet(); 176 177 /* 178 * RFC2710 page 10: 179 * The node never sends a Report or Done for the link-scope all-nodes 180 * address. 181 * MLD messages are never sent for multicast addresses whose scope is 0 182 * (reserved) or 1 (node-local). 183 */ 184 mld_all_nodes_linklocal.s6_addr16[1] = 185 htons(in6m->in6m_ifp->if_index); /* XXX */ 186 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld_all_nodes_linklocal) || 187 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) { 188 in6m->in6m_timer = 0; 189 in6m->in6m_state = MLD_OTHERLISTENER; 190 } else { 191 mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL); 192 in6m->in6m_timer = 193 MLD_RANDOM_DELAY(MLD_UNSOLICITED_REPORT_INTERVAL * 194 PR_FASTHZ); 195 in6m->in6m_state = MLD_IREPORTEDLAST; 196 mld_timers_are_running = 1; 197 } 198 splx(s); 199 } 200 201 void 202 mld6_stop_listening(in6m) 203 struct in6_multi *in6m; 204 { 205 mld_all_nodes_linklocal.s6_addr16[1] = 206 htons(in6m->in6m_ifp->if_index); /* XXX */ 207 mld_all_routers_linklocal.s6_addr16[1] = 208 htons(in6m->in6m_ifp->if_index); /* XXX: necessary when mrouting */ 209 210 if (in6m->in6m_state == MLD_IREPORTEDLAST && 211 (!IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld_all_nodes_linklocal)) && 212 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) > IPV6_ADDR_SCOPE_NODELOCAL) 213 mld6_sendpkt(in6m, MLD_LISTENER_DONE, 214 &mld_all_routers_linklocal); 215 } 216 217 void 218 mld6_input(m, off) 219 struct mbuf *m; 220 int off; 221 { 222 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 223 struct mld_hdr *mldh; 224 struct ifnet *ifp = m->m_pkthdr.rcvif; 225 struct in6_multi *in6m; 226 struct in6_ifaddr *ia; 227 int timer; /* timer value in the MLD query header */ 228 229 IP6_EXTHDR_GET(mldh, struct mld_hdr *, m, off, sizeof(*mldh)); 230 if (mldh == NULL) { 231 icmp6stat.icp6s_tooshort++; 232 return; 233 } 234 235 /* source address validation */ 236 ip6 = mtod(m, struct ip6_hdr *);/* in case mpullup */ 237 if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) { 238 #if 0 239 log(LOG_ERR, 240 "mld_input: src %s is not link-local (grp=%s)\n", 241 ip6_sprintf(&ip6->ip6_src), 242 ip6_sprintf(&mldh->mld_addr)); 243 #endif 244 /* 245 * spec (RFC2710) does not explicitly 246 * specify to discard the packet from a non link-local 247 * source address. But we believe it's expected to do so. 248 * XXX: do we have to allow :: as source? 249 */ 250 m_freem(m); 251 return; 252 } 253 254 /* 255 * In the MLD6 specification, there are 3 states and a flag. 256 * 257 * In Non-Listener state, we simply don't have a membership record. 258 * In Delaying Listener state, our timer is running (in6m->in6m_timer) 259 * In Idle Listener state, our timer is not running (in6m->in6m_timer==0) 260 * 261 * The flag is in6m->in6m_state, it is set to MLD_OTHERLISTENER if 262 * we have heard a report from another member, or MLD_IREPORTEDLAST 263 * if we sent the last report. 264 */ 265 switch (mldh->mld_type) { 266 case MLD_LISTENER_QUERY: 267 if (ifp->if_flags & IFF_LOOPBACK) 268 break; 269 270 if (!IN6_IS_ADDR_UNSPECIFIED(&mldh->mld_addr) && 271 !IN6_IS_ADDR_MULTICAST(&mldh->mld_addr)) 272 break; /* print error or log stat? */ 273 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr)) 274 mldh->mld_addr.s6_addr16[1] = 275 htons(ifp->if_index); /* XXX */ 276 277 /* 278 * - Start the timers in all of our membership records 279 * that the query applies to for the interface on 280 * which the query arrived excl. those that belong 281 * to the "all-nodes" group (ff02::1). 282 * - Restart any timer that is already running but has 283 * A value longer than the requested timeout. 284 * - Use the value specified in the query message as 285 * the maximum timeout. 286 */ 287 IFP_TO_IA6(ifp, ia); 288 if (ia == NULL) 289 break; 290 291 /* 292 * XXX: System timer resolution is too low to handle Max 293 * Response Delay, so set 1 to the internal timer even if 294 * the calculated value equals to zero when Max Response 295 * Delay is positive. 296 */ 297 timer = ntohs(mldh->mld_maxdelay)*PR_FASTHZ/MLD_TIMER_SCALE; 298 if (timer == 0 && mldh->mld_maxdelay) 299 timer = 1; 300 mld_all_nodes_linklocal.s6_addr16[1] = 301 htons(ifp->if_index); /* XXX */ 302 303 for (in6m = ia->ia6_multiaddrs.lh_first; 304 in6m; 305 in6m = in6m->in6m_entry.le_next) 306 { 307 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, 308 &mld_all_nodes_linklocal) || 309 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < 310 IPV6_ADDR_SCOPE_LINKLOCAL) 311 continue; 312 313 if (IN6_IS_ADDR_UNSPECIFIED(&mldh->mld_addr) || 314 IN6_ARE_ADDR_EQUAL(&mldh->mld_addr, 315 &in6m->in6m_addr)) 316 { 317 if (timer == 0) { 318 /* send a report immediately */ 319 mld6_sendpkt(in6m, MLD_LISTENER_REPORT, 320 NULL); 321 in6m->in6m_timer = 0; /* reset timer */ 322 in6m->in6m_state = MLD_IREPORTEDLAST; 323 } 324 else if (in6m->in6m_timer == 0 || /*idle state*/ 325 in6m->in6m_timer > timer) { 326 in6m->in6m_timer = 327 MLD_RANDOM_DELAY(timer); 328 mld_timers_are_running = 1; 329 } 330 } 331 } 332 333 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr)) 334 mldh->mld_addr.s6_addr16[1] = 0; /* XXX */ 335 break; 336 case MLD_LISTENER_REPORT: 337 /* 338 * For fast leave to work, we have to know that we are the 339 * last person to send a report for this group. Reports 340 * can potentially get looped back if we are a multicast 341 * router, so discard reports sourced by me. 342 * Note that it is impossible to check IFF_LOOPBACK flag of 343 * ifp for this purpose, since ip6_mloopback pass the physical 344 * interface to looutput. 345 */ 346 if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */ 347 break; 348 349 if (!IN6_IS_ADDR_MULTICAST(&mldh->mld_addr)) 350 break; 351 352 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr)) 353 mldh->mld_addr.s6_addr16[1] = 354 htons(ifp->if_index); /* XXX */ 355 /* 356 * If we belong to the group being reported, stop 357 * our timer for that group. 358 */ 359 IN6_LOOKUP_MULTI(mldh->mld_addr, ifp, in6m); 360 if (in6m) { 361 in6m->in6m_timer = 0; /* transit to idle state */ 362 in6m->in6m_state = MLD_OTHERLISTENER; /* clear flag */ 363 } 364 365 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr)) 366 mldh->mld_addr.s6_addr16[1] = 0; /* XXX */ 367 break; 368 default: /* this is impossible */ 369 #if 0 370 /* 371 * this case should be impossible because of filtering in 372 * icmp6_input(). But we explicitly disabled this part 373 * just in case. 374 */ 375 log(LOG_ERR, "mld_input: illegal type(%d)", mldh->mld6_type); 376 #endif 377 break; 378 } 379 380 m_freem(m); 381 } 382 383 void 384 mld6_fasttimeo() 385 { 386 struct in6_multi *in6m; 387 struct in6_multistep step; 388 int s; 389 /* 390 * Quick check to see if any work needs to be done, in order 391 * to minimize the overhead of fasttimo processing. 392 */ 393 if (!mld_timers_are_running) 394 return; 395 396 s = splsoftnet(); 397 mld_timers_are_running = 0; 398 IN6_FIRST_MULTI(step, in6m); 399 while (in6m != NULL) { 400 if (in6m->in6m_timer == 0) { 401 /* do nothing */ 402 } else if (--in6m->in6m_timer == 0) { 403 mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL); 404 in6m->in6m_state = MLD_IREPORTEDLAST; 405 } else { 406 mld_timers_are_running = 1; 407 } 408 IN6_NEXT_MULTI(step, in6m); 409 } 410 splx(s); 411 } 412 413 static void 414 mld6_sendpkt(in6m, type, dst) 415 struct in6_multi *in6m; 416 int type; 417 const struct in6_addr *dst; 418 { 419 struct mbuf *mh, *md; 420 struct mld_hdr *mldh; 421 struct ip6_hdr *ip6; 422 struct ip6_moptions im6o; 423 struct in6_ifaddr *ia; 424 struct ifnet *ifp = in6m->in6m_ifp; 425 int ignflags; 426 427 /* 428 * At first, find a link local address on the outgoing interface 429 * to use as the source address of the MLD packet. 430 * We do not reject tentative addresses for MLD report to deal with 431 * the case where we first join a link-local address. 432 */ 433 ignflags = (IN6_IFF_NOTREADY|IN6_IFF_ANYCAST) & ~IN6_IFF_TENTATIVE; 434 if ((ia = in6ifa_ifpforlinklocal(ifp, ignflags)) == NULL) 435 return; 436 if ((ia->ia6_flags & IN6_IFF_TENTATIVE)) 437 ia = NULL; 438 439 /* 440 * Allocate mbufs to store ip6 header and MLD header. 441 * We allocate 2 mbufs and make chain in advance because 442 * it is more convenient when inserting the hop-by-hop option later. 443 */ 444 MGETHDR(mh, M_DONTWAIT, MT_HEADER); 445 if (mh == NULL) 446 return; 447 MGET(md, M_DONTWAIT, MT_DATA); 448 if (md == NULL) { 449 m_free(mh); 450 return; 451 } 452 mh->m_next = md; 453 454 mh->m_pkthdr.rcvif = NULL; 455 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld_hdr); 456 mh->m_len = sizeof(struct ip6_hdr); 457 MH_ALIGN(mh, sizeof(struct ip6_hdr)); 458 459 /* fill in the ip6 header */ 460 ip6 = mtod(mh, struct ip6_hdr *); 461 ip6->ip6_flow = 0; 462 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 463 ip6->ip6_vfc |= IPV6_VERSION; 464 /* ip6_plen will be set later */ 465 ip6->ip6_nxt = IPPROTO_ICMPV6; 466 /* ip6_hlim will be set by im6o.im6o_multicast_hlim */ 467 ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any; 468 ip6->ip6_dst = dst ? *dst : in6m->in6m_addr; 469 470 /* fill in the MLD header */ 471 md->m_len = sizeof(struct mld_hdr); 472 mldh = mtod(md, struct mld_hdr *); 473 mldh->mld_type = type; 474 mldh->mld_code = 0; 475 mldh->mld_cksum = 0; 476 /* XXX: we assume the function will not be called for query messages */ 477 mldh->mld_maxdelay = 0; 478 mldh->mld_reserved = 0; 479 mldh->mld_addr = in6m->in6m_addr; 480 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld_addr)) 481 mldh->mld_addr.s6_addr16[1] = 0; /* XXX */ 482 mldh->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), 483 sizeof(struct mld_hdr)); 484 485 /* construct multicast option */ 486 bzero(&im6o, sizeof(im6o)); 487 im6o.im6o_multicast_ifp = ifp; 488 im6o.im6o_multicast_hlim = 1; 489 490 /* 491 * Request loopback of the report if we are acting as a multicast 492 * router, so that the process-level routing daemon can hear it. 493 */ 494 im6o.im6o_multicast_loop = (ip6_mrouter != NULL); 495 496 /* increment output statictics */ 497 icmp6stat.icp6s_outhist[type]++; 498 icmp6_ifstat_inc(ifp, ifs6_out_msg); 499 switch (type) { 500 case MLD_LISTENER_QUERY: 501 icmp6_ifstat_inc(ifp, ifs6_out_mldquery); 502 break; 503 case MLD_LISTENER_REPORT: 504 icmp6_ifstat_inc(ifp, ifs6_out_mldreport); 505 break; 506 case MLD_LISTENER_DONE: 507 icmp6_ifstat_inc(ifp, ifs6_out_mlddone); 508 break; 509 } 510 511 ip6_output(mh, &ip6_opts, NULL, ia ? 0 : IPV6_UNSPECSRC, 512 &im6o, (struct socket *)NULL, NULL); 513 } 514
Indexes created Tue Sep 23 07:09:52 GMT 2025