mld6.c revision 1.16
1 /* $NetBSD: mld6.c,v 1.16 2001/11/13 00:57:04 lukem 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 1.16 2001/11/13 00:57:04 lukem 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 log(LOG_ERR, 211 "mld6_input: src %s is not link-local (grp=%s)\n", 212 ip6_sprintf(&ip6->ip6_src), 213 ip6_sprintf(&mldh->mld6_addr)); 214 /* 215 * spec (RFC2710) does not explicitly 216 * specify to discard the packet from a non link-local 217 * source address. But we believe it's expected to do so. 218 * XXX: do we have to allow :: as source? 219 */ 220 m_freem(m); 221 return; 222 } 223 224 /* 225 * In the MLD6 specification, there are 3 states and a flag. 226 * 227 * In Non-Listener state, we simply don't have a membership record. 228 * In Delaying Listener state, our timer is running (in6m->in6m_timer) 229 * In Idle Listener state, our timer is not running (in6m->in6m_timer==0) 230 * 231 * The flag is in6m->in6m_state, it is set to MLD6_OTHERLISTENER if 232 * we have heard a report from another member, or MLD6_IREPORTEDLAST 233 * if we sent the last report. 234 */ 235 switch(mldh->mld6_type) { 236 case MLD6_LISTENER_QUERY: 237 if (ifp->if_flags & IFF_LOOPBACK) 238 break; 239 240 if (!IN6_IS_ADDR_UNSPECIFIED(&mldh->mld6_addr) && 241 !IN6_IS_ADDR_MULTICAST(&mldh->mld6_addr)) 242 break; /* print error or log stat? */ 243 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 244 mldh->mld6_addr.s6_addr16[1] = 245 htons(ifp->if_index); /* XXX */ 246 247 /* 248 * - Start the timers in all of our membership records 249 * that the query applies to for the interface on 250 * which the query arrived excl. those that belong 251 * to the "all-nodes" group (ff02::1). 252 * - Restart any timer that is already running but has 253 * A value longer than the requested timeout. 254 * - Use the value specified in the query message as 255 * the maximum timeout. 256 */ 257 IFP_TO_IA6(ifp, ia); 258 if (ia == NULL) 259 break; 260 261 /* 262 * XXX: System timer resolution is too low to handle Max 263 * Response Delay, so set 1 to the internal timer even if 264 * the calculated value equals to zero when Max Response 265 * Delay is positive. 266 */ 267 timer = ntohs(mldh->mld6_maxdelay)*PR_FASTHZ/MLD6_TIMER_SCALE; 268 if (timer == 0 && mldh->mld6_maxdelay) 269 timer = 1; 270 mld6_all_nodes_linklocal.s6_addr16[1] = 271 htons(ifp->if_index); /* XXX */ 272 273 for (in6m = ia->ia6_multiaddrs.lh_first; 274 in6m; 275 in6m = in6m->in6m_entry.le_next) 276 { 277 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, 278 &mld6_all_nodes_linklocal) || 279 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < 280 IPV6_ADDR_SCOPE_LINKLOCAL) 281 continue; 282 283 if (IN6_IS_ADDR_UNSPECIFIED(&mldh->mld6_addr) || 284 IN6_ARE_ADDR_EQUAL(&mldh->mld6_addr, 285 &in6m->in6m_addr)) 286 { 287 if (timer == 0) { 288 /* send a report immediately */ 289 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, 290 NULL); 291 in6m->in6m_timer = 0; /* reset timer */ 292 in6m->in6m_state = MLD6_IREPORTEDLAST; 293 } 294 else if (in6m->in6m_timer == 0 || /*idle state*/ 295 in6m->in6m_timer > timer) { 296 in6m->in6m_timer = 297 MLD6_RANDOM_DELAY(timer); 298 mld6_timers_are_running = 1; 299 } 300 } 301 } 302 303 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 304 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 305 break; 306 case MLD6_LISTENER_REPORT: 307 /* 308 * For fast leave to work, we have to know that we are the 309 * last person to send a report for this group. Reports 310 * can potentially get looped back if we are a multicast 311 * router, so discard reports sourced by me. 312 * Note that it is impossible to check IFF_LOOPBACK flag of 313 * ifp for this purpose, since ip6_mloopback pass the physical 314 * interface to looutput. 315 */ 316 if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */ 317 break; 318 319 if (!IN6_IS_ADDR_MULTICAST(&mldh->mld6_addr)) 320 break; 321 322 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 323 mldh->mld6_addr.s6_addr16[1] = 324 htons(ifp->if_index); /* XXX */ 325 /* 326 * If we belong to the group being reported, stop 327 * our timer for that group. 328 */ 329 IN6_LOOKUP_MULTI(mldh->mld6_addr, ifp, in6m); 330 if (in6m) { 331 in6m->in6m_timer = 0; /* transit to idle state */ 332 in6m->in6m_state = MLD6_OTHERLISTENER; /* clear flag */ 333 } 334 335 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 336 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 337 break; 338 default: /* this is impossible */ 339 log(LOG_ERR, "mld6_input: illegal type(%d)", mldh->mld6_type); 340 break; 341 } 342 343 m_freem(m); 344 } 345 346 void 347 mld6_fasttimeo() 348 { 349 struct in6_multi *in6m; 350 struct in6_multistep step; 351 int s; 352 353 /* 354 * Quick check to see if any work needs to be done, in order 355 * to minimize the overhead of fasttimo processing. 356 */ 357 if (!mld6_timers_are_running) 358 return; 359 360 s = splsoftnet(); 361 mld6_timers_are_running = 0; 362 IN6_FIRST_MULTI(step, in6m); 363 while (in6m != NULL) { 364 if (in6m->in6m_timer == 0) { 365 /* do nothing */ 366 } else if (--in6m->in6m_timer == 0) { 367 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, NULL); 368 in6m->in6m_state = MLD6_IREPORTEDLAST; 369 } else { 370 mld6_timers_are_running = 1; 371 } 372 IN6_NEXT_MULTI(step, in6m); 373 } 374 splx(s); 375 } 376 377 static void 378 mld6_sendpkt(in6m, type, dst) 379 struct in6_multi *in6m; 380 int type; 381 const struct in6_addr *dst; 382 { 383 struct mbuf *mh, *md; 384 struct mld6_hdr *mldh; 385 struct ip6_hdr *ip6; 386 struct ip6_moptions im6o; 387 struct in6_ifaddr *ia; 388 struct ifnet *ifp = in6m->in6m_ifp; 389 390 /* 391 * At first, find a link local address on the outgoing interface 392 * to use as the source address of the MLD packet. 393 */ 394 if ((ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST)) 395 == NULL) 396 return; 397 398 /* 399 * Allocate mbufs to store ip6 header and MLD header. 400 * We allocate 2 mbufs and make chain in advance because 401 * it is more convenient when inserting the hop-by-hop option later. 402 */ 403 MGETHDR(mh, M_DONTWAIT, MT_HEADER); 404 if (mh == NULL) 405 return; 406 MGET(md, M_DONTWAIT, MT_DATA); 407 if (md == NULL) { 408 m_free(mh); 409 return; 410 } 411 mh->m_next = md; 412 413 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld6_hdr); 414 mh->m_len = sizeof(struct ip6_hdr); 415 MH_ALIGN(mh, sizeof(struct ip6_hdr)); 416 417 /* fill in the ip6 header */ 418 ip6 = mtod(mh, struct ip6_hdr *); 419 ip6->ip6_flow = 0; 420 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 421 ip6->ip6_vfc |= IPV6_VERSION; 422 /* ip6_plen will be set later */ 423 ip6->ip6_nxt = IPPROTO_ICMPV6; 424 /* ip6_hlim will be set by im6o.im6o_multicast_hlim */ 425 ip6->ip6_src = ia->ia_addr.sin6_addr; 426 ip6->ip6_dst = dst ? *dst : in6m->in6m_addr; 427 428 /* fill in the MLD header */ 429 md->m_len = sizeof(struct mld6_hdr); 430 mldh = mtod(md, struct mld6_hdr *); 431 mldh->mld6_type = type; 432 mldh->mld6_code = 0; 433 mldh->mld6_cksum = 0; 434 /* XXX: we assume the function will not be called for query messages */ 435 mldh->mld6_maxdelay = 0; 436 mldh->mld6_reserved = 0; 437 mldh->mld6_addr = in6m->in6m_addr; 438 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 439 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 440 mldh->mld6_cksum = in6_cksum(mh, IPPROTO_ICMPV6, 441 sizeof(struct ip6_hdr), 442 sizeof(struct mld6_hdr)); 443 444 /* construct multicast option */ 445 bzero(&im6o, sizeof(im6o)); 446 im6o.im6o_multicast_ifp = ifp; 447 im6o.im6o_multicast_hlim = 1; 448 449 /* 450 * Request loopback of the report if we are acting as a multicast 451 * router, so that the process-level routing daemon can hear it. 452 */ 453 im6o.im6o_multicast_loop = (ip6_mrouter != NULL); 454 455 /* increment output statictics */ 456 icmp6stat.icp6s_outhist[type]++; 457 458 ip6_output(mh, &ip6_opts, NULL, 0, &im6o, NULL); 459 icmp6_ifstat_inc(ifp, ifs6_out_msg); 460 switch(type) { 461 case MLD6_LISTENER_QUERY: 462 icmp6_ifstat_inc(ifp, ifs6_out_mldquery); 463 break; 464 case MLD6_LISTENER_REPORT: 465 icmp6_ifstat_inc(ifp, ifs6_out_mldreport); 466 break; 467 case MLD6_LISTENER_DONE: 468 icmp6_ifstat_inc(ifp, ifs6_out_mlddone); 469 break; 470 } 471 } 472
Indexes created Tue Sep 23 14:10:03 GMT 2025