mld6.c revision 1.11
1 /* $NetBSD: mld6.c,v 1.11 2000/02/26 08:39:20 itojun 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 #include "opt_ipsec.h" 74 75 #include <sys/param.h> 76 #include <sys/systm.h> 77 #include <sys/mbuf.h> 78 #include <sys/socket.h> 79 #include <sys/protosw.h> 80 #include <sys/syslog.h> 81 82 #include <net/if.h> 83 84 #include <netinet/in.h> 85 #include <netinet/in_var.h> 86 #include <netinet/ip6.h> 87 #include <netinet6/ip6_var.h> 88 #include <netinet/icmp6.h> 89 #include <netinet6/mld6_var.h> 90 91 #include <net/net_osdep.h> 92 93 /* 94 * Protocol constants 95 */ 96 97 /* denotes that the MLD max response delay field specifies time in milliseconds */ 98 #define MLD6_TIMER_SCALE 1000 99 /* 100 * time between repetitions of a node's initial report of interest in a 101 * multicast address(in seconds) 102 */ 103 #define MLD6_UNSOLICITED_REPORT_INTERVAL 10 104 105 static struct ip6_pktopts ip6_opts; 106 static int mld6_timers_are_running; 107 /* XXX: These are necessary for KAME's link-local hack */ 108 static struct in6_addr mld6_all_nodes_linklocal = IN6ADDR_LINKLOCAL_ALLNODES_INIT; 109 static struct in6_addr mld6_all_routers_linklocal = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT; 110 111 static void mld6_sendpkt __P((struct in6_multi *, int, const struct in6_addr *)); 112 113 void 114 mld6_init() 115 { 116 static u_int8_t hbh_buf[8]; 117 struct ip6_hbh *hbh = (struct ip6_hbh *)hbh_buf; 118 u_int16_t rtalert_code = htons((u_int16_t)IP6OPT_RTALERT_MLD); 119 120 mld6_timers_are_running = 0; 121 122 /* ip6h_nxt will be fill in later */ 123 hbh->ip6h_len = 0; /* (8 >> 3) - 1 */ 124 125 /* XXX: grotty hard coding... */ 126 hbh_buf[2] = IP6OPT_PADN; /* 2 byte padding */ 127 hbh_buf[3] = 0; 128 hbh_buf[4] = IP6OPT_RTALERT; 129 hbh_buf[5] = IP6OPT_RTALERT_LEN - 2; 130 bcopy((caddr_t)&rtalert_code, &hbh_buf[6], sizeof(u_int16_t)); 131 132 ip6_opts.ip6po_hbh = hbh; 133 /* We will specify the hoplimit by a multicast option. */ 134 ip6_opts.ip6po_hlim = -1; 135 } 136 137 void 138 mld6_start_listening(in6m) 139 struct in6_multi *in6m; 140 { 141 int s = splsoftnet(); 142 143 /* 144 * RFC2710 page 10: 145 * The node never sends a Report or Done for the link-scope all-nodes 146 * address. 147 * MLD messages are never sent for multicast addresses whose scope is 0 148 * (reserved) or 1 (node-local). 149 */ 150 mld6_all_nodes_linklocal.s6_addr16[1] = 151 htons(in6m->in6m_ifp->if_index); /* XXX */ 152 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal) || 153 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) { 154 in6m->in6m_timer = 0; 155 in6m->in6m_state = MLD6_OTHERLISTENER; 156 } else { 157 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, NULL); 158 in6m->in6m_timer = MLD6_RANDOM_DELAY( 159 MLD6_UNSOLICITED_REPORT_INTERVAL * PR_FASTHZ); 160 in6m->in6m_state = MLD6_IREPORTEDLAST; 161 mld6_timers_are_running = 1; 162 } 163 splx(s); 164 } 165 166 void 167 mld6_stop_listening(in6m) 168 struct in6_multi *in6m; 169 { 170 mld6_all_nodes_linklocal.s6_addr16[1] = 171 htons(in6m->in6m_ifp->if_index); /* XXX */ 172 mld6_all_routers_linklocal.s6_addr16[1] = 173 htons(in6m->in6m_ifp->if_index); /* XXX: necessary when mrouting */ 174 175 if (in6m->in6m_state == MLD6_IREPORTEDLAST && 176 (!IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal)) && 177 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) > IPV6_ADDR_SCOPE_NODELOCAL) 178 mld6_sendpkt(in6m, MLD6_LISTENER_DONE, 179 &mld6_all_routers_linklocal); 180 } 181 182 void 183 mld6_input(m, off) 184 struct mbuf *m; 185 int off; 186 { 187 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 188 struct mld6_hdr *mldh; 189 struct ifnet *ifp = m->m_pkthdr.rcvif; 190 struct in6_multi *in6m; 191 struct in6_ifaddr *ia; 192 int timer; /* timer value in the MLD query header */ 193 194 /* source address validation */ 195 if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) { 196 log(LOG_ERR, 197 "mld6_input: src %s is not link-local\n", 198 ip6_sprintf(&ip6->ip6_src)); 199 /* 200 * spec (RFC2710) does not explicitly 201 * specify to discard the packet from a non link-local 202 * source address. But we believe it's expected to do so. 203 */ 204 m_freem(m); 205 return; 206 } 207 208 #ifndef PULLDOWN_TEST 209 IP6_EXTHDR_CHECK(m, off, sizeof(*mldh),); 210 mldh = (struct mld6_hdr *)(mtod(m, caddr_t) + off); 211 #else 212 IP6_EXTHDR_GET(mldh, struct mld6_hdr *, m, off, sizeof(*mldh)); 213 if (mldh == NULL) { 214 icmp6stat.icp6s_tooshort++; 215 return; 216 } 217 #endif 218 219 /* 220 * In the MLD6 specification, there are 3 states and a flag. 221 * 222 * In Non-Listener state, we simply don't have a membership record. 223 * In Delaying Listener state, our timer is running (in6m->in6m_timer) 224 * In Idle Listener state, our timer is not running (in6m->in6m_timer==0) 225 * 226 * The flag is in6m->in6m_state, it is set to MLD6_OTHERLISTENER if 227 * we have heard a report from another member, or MLD6_IREPORTEDLAST 228 * if we sent the last report. 229 */ 230 switch(mldh->mld6_type) { 231 case MLD6_LISTENER_QUERY: 232 if (ifp->if_flags & IFF_LOOPBACK) 233 break; 234 235 if (!IN6_IS_ADDR_UNSPECIFIED(&mldh->mld6_addr) && 236 !IN6_IS_ADDR_MULTICAST(&mldh->mld6_addr)) 237 break; /* print error or log stat? */ 238 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 239 mldh->mld6_addr.s6_addr16[1] = 240 htons(ifp->if_index); /* XXX */ 241 242 /* 243 * - Start the timers in all of our membership records 244 * that the query applies to for the interface on 245 * which the query arrived excl. those that belong 246 * to the "all-nodes" group (ff02::1). 247 * - Restart any timer that is already running but has 248 * A value longer than the requested timeout. 249 * - Use the value specified in the query message as 250 * the maximum timeout. 251 */ 252 IFP_TO_IA6(ifp, ia); 253 if (ia == NULL) 254 break; 255 256 /* 257 * XXX: System timer resolution is too low to handle Max 258 * Response Delay, so set 1 to the internal timer even if 259 * the calculated value equals to zero when Max Response 260 * Delay is positive. 261 */ 262 timer = ntohs(mldh->mld6_maxdelay)*PR_FASTHZ/MLD6_TIMER_SCALE; 263 if (timer == 0 && mldh->mld6_maxdelay) 264 timer = 1; 265 mld6_all_nodes_linklocal.s6_addr16[1] = 266 htons(ifp->if_index); /* XXX */ 267 268 for (in6m = ia->ia6_multiaddrs.lh_first; 269 in6m; 270 in6m = in6m->in6m_entry.le_next) 271 { 272 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, 273 &mld6_all_nodes_linklocal) || 274 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < 275 IPV6_ADDR_SCOPE_LINKLOCAL) 276 continue; 277 278 if (IN6_IS_ADDR_UNSPECIFIED(&mldh->mld6_addr) || 279 IN6_ARE_ADDR_EQUAL(&mldh->mld6_addr, 280 &in6m->in6m_addr)) 281 { 282 if (timer == 0) { 283 /* send a report immediately */ 284 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, 285 NULL); 286 in6m->in6m_timer = 0; /* reset timer */ 287 in6m->in6m_state = MLD6_IREPORTEDLAST; 288 } 289 else if (in6m->in6m_timer == 0 || /*idle state*/ 290 in6m->in6m_timer > timer) { 291 in6m->in6m_timer = 292 MLD6_RANDOM_DELAY(timer); 293 mld6_timers_are_running = 1; 294 } 295 } 296 } 297 298 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 299 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 300 break; 301 case MLD6_LISTENER_REPORT: 302 /* 303 * For fast leave to work, we have to know that we are the 304 * last person to send a report for this group. Reports 305 * can potentially get looped back if we are a multicast 306 * router, so discard reports sourced by me. 307 * Note that it is impossible to check IFF_LOOPBACK flag of 308 * ifp for this purpose, since ip6_mloopback pass the physical 309 * interface to looutput. 310 */ 311 if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */ 312 break; 313 314 if (!IN6_IS_ADDR_MULTICAST(&mldh->mld6_addr)) 315 break; 316 317 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 318 mldh->mld6_addr.s6_addr16[1] = 319 htons(ifp->if_index); /* XXX */ 320 /* 321 * If we belong to the group being reported, stop 322 * our timer for that group. 323 */ 324 IN6_LOOKUP_MULTI(mldh->mld6_addr, ifp, in6m); 325 if (in6m) { 326 in6m->in6m_timer = 0; /* transit to idle state */ 327 in6m->in6m_state = MLD6_OTHERLISTENER; /* clear flag */ 328 } 329 330 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 331 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 332 break; 333 default: /* this is impossible */ 334 log(LOG_ERR, "mld6_input: illegal type(%d)", mldh->mld6_type); 335 break; 336 } 337 338 m_freem(m); 339 } 340 341 void 342 mld6_fasttimeo() 343 { 344 register struct in6_multi *in6m; 345 struct in6_multistep step; 346 int s; 347 348 /* 349 * Quick check to see if any work needs to be done, in order 350 * to minimize the overhead of fasttimo processing. 351 */ 352 if (!mld6_timers_are_running) 353 return; 354 355 s = splsoftnet(); 356 mld6_timers_are_running = 0; 357 IN6_FIRST_MULTI(step, in6m); 358 while (in6m != NULL) { 359 if (in6m->in6m_timer == 0) { 360 /* do nothing */ 361 } else if (--in6m->in6m_timer == 0) { 362 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, NULL); 363 in6m->in6m_state = MLD6_IREPORTEDLAST; 364 } else { 365 mld6_timers_are_running = 1; 366 } 367 IN6_NEXT_MULTI(step, in6m); 368 } 369 splx(s); 370 } 371 372 static void 373 mld6_sendpkt(in6m, type, dst) 374 struct in6_multi *in6m; 375 int type; 376 const struct in6_addr *dst; 377 { 378 struct mbuf *mh, *md; 379 struct mld6_hdr *mldh; 380 struct ip6_hdr *ip6; 381 struct ip6_moptions im6o; 382 struct in6_ifaddr *ia; 383 struct ifnet *ifp = in6m->in6m_ifp; 384 struct ifnet *outif = NULL; 385 386 /* 387 * At first, find a link local address on the outgoing interface 388 * to use as the source address of the MLD packet. 389 */ 390 if ((ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST)) 391 == NULL) 392 return; 393 394 /* 395 * Allocate mbufs to store ip6 header and MLD header. 396 * We allocate 2 mbufs and make chain in advance because 397 * it is more convenient when inserting the hop-by-hop option later. 398 */ 399 MGETHDR(mh, M_DONTWAIT, MT_HEADER); 400 if (mh == NULL) 401 return; 402 MGET(md, M_DONTWAIT, MT_DATA); 403 if (md == NULL) { 404 m_free(mh); 405 return; 406 } 407 mh->m_next = md; 408 409 #ifdef IPSEC 410 mh->m_pkthdr.rcvif = NULL; 411 #endif 412 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld6_hdr); 413 mh->m_len = sizeof(struct ip6_hdr); 414 MH_ALIGN(mh, sizeof(struct ip6_hdr)); 415 416 /* fill in the ip6 header */ 417 ip6 = mtod(mh, struct ip6_hdr *); 418 ip6->ip6_flow = 0; 419 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 420 ip6->ip6_vfc |= IPV6_VERSION; 421 /* ip6_plen will be set later */ 422 ip6->ip6_nxt = IPPROTO_ICMPV6; 423 /* ip6_hlim will be set by im6o.im6o_multicast_hlim */ 424 ip6->ip6_src = ia->ia_addr.sin6_addr; 425 ip6->ip6_dst = dst ? *dst : in6m->in6m_addr; 426 427 /* fill in the MLD header */ 428 md->m_len = sizeof(struct mld6_hdr); 429 mldh = mtod(md, struct mld6_hdr *); 430 mldh->mld6_type = type; 431 mldh->mld6_code = 0; 432 mldh->mld6_cksum = 0; 433 /* XXX: we assume the function will not be called for query messages */ 434 mldh->mld6_maxdelay = 0; 435 mldh->mld6_reserved = 0; 436 mldh->mld6_addr = in6m->in6m_addr; 437 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 438 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 439 mldh->mld6_cksum = in6_cksum(mh, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), 440 sizeof(struct mld6_hdr)); 441 442 /* construct multicast option */ 443 bzero(&im6o, sizeof(im6o)); 444 im6o.im6o_multicast_ifp = ifp; 445 im6o.im6o_multicast_hlim = 1; 446 447 /* 448 * Request loopback of the report if we are acting as a multicast 449 * router, so that the process-level routing daemon can hear it. 450 */ 451 im6o.im6o_multicast_loop = (ip6_mrouter != NULL); 452 453 /* increment output statictics */ 454 icmp6stat.icp6s_outhist[type]++; 455 456 ip6_output(mh, &ip6_opts, NULL, 0, &im6o, &outif); 457 if (outif) { 458 icmp6_ifstat_inc(outif, ifs6_out_msg); 459 switch(type) { 460 case MLD6_LISTENER_QUERY: 461 icmp6_ifstat_inc(outif, ifs6_out_mldquery); 462 break; 463 case MLD6_LISTENER_REPORT: 464 icmp6_ifstat_inc(outif, ifs6_out_mldreport); 465 break; 466 case MLD6_LISTENER_DONE: 467 icmp6_ifstat_inc(outif, ifs6_out_mlddone); 468 break; 469 } 470 } 471 } 472
Indexes created Tue Sep 23 02:09:52 GMT 2025