mld6.c revision 1.18
1 /* $NetBSD: mld6.c,v 1.18 2002/01/08 04:37:32 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) 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 <sys/cdefs.h> 73 __KERNEL_RCSID(0, "$NetBSD: mld6.c,v 1.18 2002/01/08 04:37:32 itojun Exp $"); 74 75 #include "opt_inet.h" 76 77 #include <sys/param.h> 78 #include <sys/systm.h> 79 #include <sys/mbuf.h> 80 #include <sys/socket.h> 81 #include <sys/protosw.h> 82 #include <sys/syslog.h> 83 84 #include <net/if.h> 85 86 #include <netinet/in.h> 87 #include <netinet/in_var.h> 88 #include <netinet/ip6.h> 89 #include <netinet6/ip6_var.h> 90 #include <netinet/icmp6.h> 91 #include <netinet6/mld6_var.h> 92 93 #include <net/net_osdep.h> 94 95 /* 96 * Protocol constants 97 */ 98 99 /* denotes that the MLD max response delay field specifies time in milliseconds */ 100 #define MLD6_TIMER_SCALE 1000 101 /* 102 * time between repetitions of a node's initial report of interest in a 103 * multicast address(in seconds) 104 */ 105 #define MLD6_UNSOLICITED_REPORT_INTERVAL 10 106 107 static struct ip6_pktopts ip6_opts; 108 static int mld6_timers_are_running; 109 /* XXX: These are necessary for KAME's link-local hack */ 110 static struct in6_addr mld6_all_nodes_linklocal = IN6ADDR_LINKLOCAL_ALLNODES_INIT; 111 static struct in6_addr mld6_all_routers_linklocal = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT; 112 113 static void mld6_sendpkt __P((struct in6_multi *, int, const struct in6_addr *)); 114 115 void 116 mld6_init() 117 { 118 static u_int8_t hbh_buf[8]; 119 struct ip6_hbh *hbh = (struct ip6_hbh *)hbh_buf; 120 u_int16_t rtalert_code = htons((u_int16_t)IP6OPT_RTALERT_MLD); 121 122 mld6_timers_are_running = 0; 123 124 /* ip6h_nxt will be fill in later */ 125 hbh->ip6h_len = 0; /* (8 >> 3) - 1 */ 126 127 /* XXX: grotty hard coding... */ 128 hbh_buf[2] = IP6OPT_PADN; /* 2 byte padding */ 129 hbh_buf[3] = 0; 130 hbh_buf[4] = IP6OPT_RTALERT; 131 hbh_buf[5] = IP6OPT_RTALERT_LEN - 2; 132 bcopy((caddr_t)&rtalert_code, &hbh_buf[6], sizeof(u_int16_t)); 133 134 ip6_opts.ip6po_hbh = hbh; 135 /* We will specify the hoplimit by a multicast option. */ 136 ip6_opts.ip6po_hlim = -1; 137 } 138 139 void 140 mld6_start_listening(in6m) 141 struct in6_multi *in6m; 142 { 143 int s = splsoftnet(); 144 145 /* 146 * RFC2710 page 10: 147 * The node never sends a Report or Done for the link-scope all-nodes 148 * address. 149 * MLD messages are never sent for multicast addresses whose scope is 0 150 * (reserved) or 1 (node-local). 151 */ 152 mld6_all_nodes_linklocal.s6_addr16[1] = 153 htons(in6m->in6m_ifp->if_index); /* XXX */ 154 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal) || 155 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) { 156 in6m->in6m_timer = 0; 157 in6m->in6m_state = MLD6_OTHERLISTENER; 158 } else { 159 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, NULL); 160 in6m->in6m_timer = MLD6_RANDOM_DELAY( 161 MLD6_UNSOLICITED_REPORT_INTERVAL * PR_FASTHZ); 162 in6m->in6m_state = MLD6_IREPORTEDLAST; 163 mld6_timers_are_running = 1; 164 } 165 splx(s); 166 } 167 168 void 169 mld6_stop_listening(in6m) 170 struct in6_multi *in6m; 171 { 172 mld6_all_nodes_linklocal.s6_addr16[1] = 173 htons(in6m->in6m_ifp->if_index); /* XXX */ 174 mld6_all_routers_linklocal.s6_addr16[1] = 175 htons(in6m->in6m_ifp->if_index); /* XXX: necessary when mrouting */ 176 177 if (in6m->in6m_state == MLD6_IREPORTEDLAST && 178 (!IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal)) && 179 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) > IPV6_ADDR_SCOPE_NODELOCAL) 180 mld6_sendpkt(in6m, MLD6_LISTENER_DONE, 181 &mld6_all_routers_linklocal); 182 } 183 184 void 185 mld6_input(m, off) 186 struct mbuf *m; 187 int off; 188 { 189 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 190 struct mld6_hdr *mldh; 191 struct ifnet *ifp = m->m_pkthdr.rcvif; 192 struct in6_multi *in6m; 193 struct in6_ifaddr *ia; 194 int timer; /* timer value in the MLD query header */ 195 196 #ifndef PULLDOWN_TEST 197 IP6_EXTHDR_CHECK(m, off, sizeof(*mldh),); 198 mldh = (struct mld6_hdr *)(mtod(m, caddr_t) + off); 199 #else 200 IP6_EXTHDR_GET(mldh, struct mld6_hdr *, m, off, sizeof(*mldh)); 201 if (mldh == NULL) { 202 icmp6stat.icp6s_tooshort++; 203 return; 204 } 205 #endif 206 207 /* source address validation */ 208 ip6 = mtod(m, struct ip6_hdr *);/* in case mpullup */ 209 if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) { 210 #if 0 211 log(LOG_ERR, 212 "mld6_input: src %s is not link-local (grp=%s)\n", 213 ip6_sprintf(&ip6->ip6_src), 214 ip6_sprintf(&mldh->mld6_addr)); 215 #endif 216 /* 217 * spec (RFC2710) does not explicitly 218 * specify to discard the packet from a non link-local 219 * source address. But we believe it's expected to do so. 220 * XXX: do we have to allow :: as source? 221 */ 222 m_freem(m); 223 return; 224 } 225 226 /* 227 * In the MLD6 specification, there are 3 states and a flag. 228 * 229 * In Non-Listener state, we simply don't have a membership record. 230 * In Delaying Listener state, our timer is running (in6m->in6m_timer) 231 * In Idle Listener state, our timer is not running (in6m->in6m_timer==0) 232 * 233 * The flag is in6m->in6m_state, it is set to MLD6_OTHERLISTENER if 234 * we have heard a report from another member, or MLD6_IREPORTEDLAST 235 * if we sent the last report. 236 */ 237 switch (mldh->mld6_type) { 238 case MLD6_LISTENER_QUERY: 239 if (ifp->if_flags & IFF_LOOPBACK) 240 break; 241 242 if (!IN6_IS_ADDR_UNSPECIFIED(&mldh->mld6_addr) && 243 !IN6_IS_ADDR_MULTICAST(&mldh->mld6_addr)) 244 break; /* print error or log stat? */ 245 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 246 mldh->mld6_addr.s6_addr16[1] = 247 htons(ifp->if_index); /* XXX */ 248 249 /* 250 * - Start the timers in all of our membership records 251 * that the query applies to for the interface on 252 * which the query arrived excl. those that belong 253 * to the "all-nodes" group (ff02::1). 254 * - Restart any timer that is already running but has 255 * A value longer than the requested timeout. 256 * - Use the value specified in the query message as 257 * the maximum timeout. 258 */ 259 IFP_TO_IA6(ifp, ia); 260 if (ia == NULL) 261 break; 262 263 /* 264 * XXX: System timer resolution is too low to handle Max 265 * Response Delay, so set 1 to the internal timer even if 266 * the calculated value equals to zero when Max Response 267 * Delay is positive. 268 */ 269 timer = ntohs(mldh->mld6_maxdelay)*PR_FASTHZ/MLD6_TIMER_SCALE; 270 if (timer == 0 && mldh->mld6_maxdelay) 271 timer = 1; 272 mld6_all_nodes_linklocal.s6_addr16[1] = 273 htons(ifp->if_index); /* XXX */ 274 275 for (in6m = ia->ia6_multiaddrs.lh_first; 276 in6m; 277 in6m = in6m->in6m_entry.le_next) 278 { 279 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, 280 &mld6_all_nodes_linklocal) || 281 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < 282 IPV6_ADDR_SCOPE_LINKLOCAL) 283 continue; 284 285 if (IN6_IS_ADDR_UNSPECIFIED(&mldh->mld6_addr) || 286 IN6_ARE_ADDR_EQUAL(&mldh->mld6_addr, 287 &in6m->in6m_addr)) 288 { 289 if (timer == 0) { 290 /* send a report immediately */ 291 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, 292 NULL); 293 in6m->in6m_timer = 0; /* reset timer */ 294 in6m->in6m_state = MLD6_IREPORTEDLAST; 295 } 296 else if (in6m->in6m_timer == 0 || /*idle state*/ 297 in6m->in6m_timer > timer) { 298 in6m->in6m_timer = 299 MLD6_RANDOM_DELAY(timer); 300 mld6_timers_are_running = 1; 301 } 302 } 303 } 304 305 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 306 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 307 break; 308 case MLD6_LISTENER_REPORT: 309 /* 310 * For fast leave to work, we have to know that we are the 311 * last person to send a report for this group. Reports 312 * can potentially get looped back if we are a multicast 313 * router, so discard reports sourced by me. 314 * Note that it is impossible to check IFF_LOOPBACK flag of 315 * ifp for this purpose, since ip6_mloopback pass the physical 316 * interface to looutput. 317 */ 318 if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */ 319 break; 320 321 if (!IN6_IS_ADDR_MULTICAST(&mldh->mld6_addr)) 322 break; 323 324 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 325 mldh->mld6_addr.s6_addr16[1] = 326 htons(ifp->if_index); /* XXX */ 327 /* 328 * If we belong to the group being reported, stop 329 * our timer for that group. 330 */ 331 IN6_LOOKUP_MULTI(mldh->mld6_addr, ifp, in6m); 332 if (in6m) { 333 in6m->in6m_timer = 0; /* transit to idle state */ 334 in6m->in6m_state = MLD6_OTHERLISTENER; /* clear flag */ 335 } 336 337 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 338 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 339 break; 340 default: /* this is impossible */ 341 #if 0 342 log(LOG_ERR, "mld6_input: illegal type(%d)", mldh->mld6_type); 343 #endif 344 break; 345 } 346 347 m_freem(m); 348 } 349 350 void 351 mld6_fasttimeo() 352 { 353 struct in6_multi *in6m; 354 struct in6_multistep step; 355 int s; 356 357 /* 358 * Quick check to see if any work needs to be done, in order 359 * to minimize the overhead of fasttimo processing. 360 */ 361 if (!mld6_timers_are_running) 362 return; 363 364 s = splsoftnet(); 365 mld6_timers_are_running = 0; 366 IN6_FIRST_MULTI(step, in6m); 367 while (in6m != NULL) { 368 if (in6m->in6m_timer == 0) { 369 /* do nothing */ 370 } else if (--in6m->in6m_timer == 0) { 371 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, NULL); 372 in6m->in6m_state = MLD6_IREPORTEDLAST; 373 } else { 374 mld6_timers_are_running = 1; 375 } 376 IN6_NEXT_MULTI(step, in6m); 377 } 378 splx(s); 379 } 380 381 static void 382 mld6_sendpkt(in6m, type, dst) 383 struct in6_multi *in6m; 384 int type; 385 const struct in6_addr *dst; 386 { 387 struct mbuf *mh, *md; 388 struct mld6_hdr *mldh; 389 struct ip6_hdr *ip6; 390 struct ip6_moptions im6o; 391 struct in6_ifaddr *ia; 392 struct ifnet *ifp = in6m->in6m_ifp; 393 394 /* 395 * At first, find a link local address on the outgoing interface 396 * to use as the source address of the MLD packet. 397 */ 398 if ((ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST)) 399 == NULL) 400 return; 401 402 /* 403 * Allocate mbufs to store ip6 header and MLD header. 404 * We allocate 2 mbufs and make chain in advance because 405 * it is more convenient when inserting the hop-by-hop option later. 406 */ 407 MGETHDR(mh, M_DONTWAIT, MT_HEADER); 408 if (mh == NULL) 409 return; 410 MGET(md, M_DONTWAIT, MT_DATA); 411 if (md == NULL) { 412 m_free(mh); 413 return; 414 } 415 mh->m_next = md; 416 417 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld6_hdr); 418 mh->m_len = sizeof(struct ip6_hdr); 419 MH_ALIGN(mh, sizeof(struct ip6_hdr)); 420 421 /* fill in the ip6 header */ 422 ip6 = mtod(mh, struct ip6_hdr *); 423 ip6->ip6_flow = 0; 424 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 425 ip6->ip6_vfc |= IPV6_VERSION; 426 /* ip6_plen will be set later */ 427 ip6->ip6_nxt = IPPROTO_ICMPV6; 428 /* ip6_hlim will be set by im6o.im6o_multicast_hlim */ 429 ip6->ip6_src = ia->ia_addr.sin6_addr; 430 ip6->ip6_dst = dst ? *dst : in6m->in6m_addr; 431 432 /* fill in the MLD header */ 433 md->m_len = sizeof(struct mld6_hdr); 434 mldh = mtod(md, struct mld6_hdr *); 435 mldh->mld6_type = type; 436 mldh->mld6_code = 0; 437 mldh->mld6_cksum = 0; 438 /* XXX: we assume the function will not be called for query messages */ 439 mldh->mld6_maxdelay = 0; 440 mldh->mld6_reserved = 0; 441 mldh->mld6_addr = in6m->in6m_addr; 442 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 443 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 444 mldh->mld6_cksum = in6_cksum(mh, IPPROTO_ICMPV6, 445 sizeof(struct ip6_hdr), 446 sizeof(struct mld6_hdr)); 447 448 /* construct multicast option */ 449 bzero(&im6o, sizeof(im6o)); 450 im6o.im6o_multicast_ifp = ifp; 451 im6o.im6o_multicast_hlim = 1; 452 453 /* 454 * Request loopback of the report if we are acting as a multicast 455 * router, so that the process-level routing daemon can hear it. 456 */ 457 im6o.im6o_multicast_loop = (ip6_mrouter != NULL); 458 459 /* increment output statictics */ 460 icmp6stat.icp6s_outhist[type]++; 461 462 ip6_output(mh, &ip6_opts, NULL, 0, &im6o, NULL); 463 icmp6_ifstat_inc(ifp, ifs6_out_msg); 464 switch (type) { 465 case MLD6_LISTENER_QUERY: 466 icmp6_ifstat_inc(ifp, ifs6_out_mldquery); 467 break; 468 case MLD6_LISTENER_REPORT: 469 icmp6_ifstat_inc(ifp, ifs6_out_mldreport); 470 break; 471 case MLD6_LISTENER_DONE: 472 icmp6_ifstat_inc(ifp, ifs6_out_mlddone); 473 break; 474 } 475 } 476
Indexes created Mon Sep 22 05:09:51 GMT 2025