mld6.c revision 1.9
1 /* $NetBSD: mld6.c,v 1.9 2000/01/06 15:46:10 itojun Exp $ */ 2 3 /* 4 * Copyright (C) 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * Copyright (c) 1988 Stephen Deering. 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. All advertising materials mentioning features or use of this software 49 * must display the following acknowledgement: 50 * This product includes software developed by the University of 51 * California, Berkeley and its contributors. 52 * 4. Neither the name of the University nor the names of its contributors 53 * may be used to endorse or promote products derived from this software 54 * without specific prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 57 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 58 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 59 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 60 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 61 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 62 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 63 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 64 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 65 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 66 * SUCH DAMAGE. 67 * 68 * @(#)igmp.c 8.1 (Berkeley) 7/19/93 69 */ 70 71 #include "opt_inet.h" 72 #include "opt_ipsec.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 <netinet6/ip6.h> 86 #include <netinet6/ip6_var.h> 87 #include <netinet6/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 * (draft-ietf-ipngwg-mld, 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 = (struct mld6_hdr *)(mtod(m, caddr_t) + off); 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(draft-ietf-ipngwg-mld) 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 return; 204 } 205 206 /* 207 * In the MLD6 specification, there are 3 states and a flag. 208 * 209 * In Non-Listener state, we simply don't have a membership record. 210 * In Delaying Listener state, our timer is running (in6m->in6m_timer) 211 * In Idle Listener state, our timer is not running (in6m->in6m_timer==0) 212 * 213 * The flag is in6m->in6m_state, it is set to MLD6_OTHERLISTENER if 214 * we have heard a report from another member, or MLD6_IREPORTEDLAST 215 * if we sent the last report. 216 */ 217 switch(mldh->mld6_type) { 218 case MLD6_LISTENER_QUERY: 219 if (ifp->if_flags & IFF_LOOPBACK) 220 break; 221 222 if (!IN6_IS_ADDR_UNSPECIFIED(&mldh->mld6_addr) && 223 !IN6_IS_ADDR_MULTICAST(&mldh->mld6_addr)) 224 break; /* print error or log stat? */ 225 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 226 mldh->mld6_addr.s6_addr16[1] = 227 htons(ifp->if_index); /* XXX */ 228 229 /* 230 * - Start the timers in all of our membership records 231 * that the query applies to for the interface on 232 * which the query arrived excl. those that belong 233 * to the "all-nodes" group (ff02::1). 234 * - Restart any timer that is already running but has 235 * A value longer than the requested timeout. 236 * - Use the value specified in the query message as 237 * the maximum timeout. 238 */ 239 IFP_TO_IA6(ifp, ia); 240 if (ia == NULL) 241 break; 242 243 /* 244 * XXX: System timer resolution is too low to handle Max 245 * Response Delay, so set 1 to the internal timer even if 246 * the calculated value equals to zero when Max Response 247 * Delay is positive. 248 */ 249 timer = ntohs(mldh->mld6_maxdelay)*PR_FASTHZ/MLD6_TIMER_SCALE; 250 if (timer == 0 && mldh->mld6_maxdelay) 251 timer = 1; 252 mld6_all_nodes_linklocal.s6_addr16[1] = 253 htons(ifp->if_index); /* XXX */ 254 255 for (in6m = ia->ia6_multiaddrs.lh_first; 256 in6m; 257 in6m = in6m->in6m_entry.le_next) 258 { 259 if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, 260 &mld6_all_nodes_linklocal) || 261 IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < 262 IPV6_ADDR_SCOPE_LINKLOCAL) 263 continue; 264 265 if (IN6_IS_ADDR_UNSPECIFIED(&mldh->mld6_addr) || 266 IN6_ARE_ADDR_EQUAL(&mldh->mld6_addr, 267 &in6m->in6m_addr)) 268 { 269 if (timer == 0) { 270 /* send a report immediately */ 271 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, 272 NULL); 273 in6m->in6m_timer = 0; /* reset timer */ 274 in6m->in6m_state = MLD6_IREPORTEDLAST; 275 } 276 else if (in6m->in6m_timer == 0 || /*idle state*/ 277 in6m->in6m_timer > timer) { 278 in6m->in6m_timer = 279 MLD6_RANDOM_DELAY(timer); 280 mld6_timers_are_running = 1; 281 } 282 } 283 } 284 285 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 286 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 287 break; 288 case MLD6_LISTENER_REPORT: 289 /* 290 * For fast leave to work, we have to know that we are the 291 * last person to send a report for this group. Reports 292 * can potentially get looped back if we are a multicast 293 * router, so discard reports sourced by me. 294 * Note that it is impossible to check IFF_LOOPBACK flag of 295 * ifp for this purpose, since ip6_mloopback pass the physical 296 * interface to looutput. 297 */ 298 if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */ 299 break; 300 301 if (!IN6_IS_ADDR_MULTICAST(&mldh->mld6_addr)) 302 break; 303 304 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 305 mldh->mld6_addr.s6_addr16[1] = 306 htons(ifp->if_index); /* XXX */ 307 /* 308 * If we belong to the group being reported, stop 309 * our timer for that group. 310 */ 311 IN6_LOOKUP_MULTI(mldh->mld6_addr, ifp, in6m); 312 if (in6m) { 313 in6m->in6m_timer = 0; /* transit to idle state */ 314 in6m->in6m_state = MLD6_OTHERLISTENER; /* clear flag */ 315 } 316 317 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 318 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 319 break; 320 default: /* this is impossible */ 321 log(LOG_ERR, "mld6_input: illegal type(%d)", mldh->mld6_type); 322 break; 323 } 324 } 325 326 void 327 mld6_fasttimeo() 328 { 329 register struct in6_multi *in6m; 330 struct in6_multistep step; 331 int s; 332 333 /* 334 * Quick check to see if any work needs to be done, in order 335 * to minimize the overhead of fasttimo processing. 336 */ 337 if (!mld6_timers_are_running) 338 return; 339 340 s = splsoftnet(); 341 mld6_timers_are_running = 0; 342 IN6_FIRST_MULTI(step, in6m); 343 while (in6m != NULL) { 344 if (in6m->in6m_timer == 0) { 345 /* do nothing */ 346 } else if (--in6m->in6m_timer == 0) { 347 mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, NULL); 348 in6m->in6m_state = MLD6_IREPORTEDLAST; 349 } else { 350 mld6_timers_are_running = 1; 351 } 352 IN6_NEXT_MULTI(step, in6m); 353 } 354 splx(s); 355 } 356 357 static void 358 mld6_sendpkt(in6m, type, dst) 359 struct in6_multi *in6m; 360 int type; 361 const struct in6_addr *dst; 362 { 363 struct mbuf *mh, *md; 364 struct mld6_hdr *mldh; 365 struct ip6_hdr *ip6; 366 struct ip6_moptions im6o; 367 struct in6_ifaddr *ia; 368 struct ifnet *ifp = in6m->in6m_ifp; 369 struct ifnet *outif = NULL; 370 371 /* 372 * At first, find a link local address on the outgoing interface 373 * to use as the source address of the MLD packet. 374 */ 375 if ((ia = in6ifa_ifpforlinklocal(ifp)) == NULL) 376 return; 377 378 /* 379 * Allocate mbufs to store ip6 header and MLD header. 380 * We allocate 2 mbufs and make chain in advance because 381 * it is more convenient when inserting the hop-by-hop option later. 382 */ 383 MGETHDR(mh, M_DONTWAIT, MT_HEADER); 384 if (mh == NULL) 385 return; 386 MGET(md, M_DONTWAIT, MT_DATA); 387 if (md == NULL) { 388 m_free(mh); 389 return; 390 } 391 mh->m_next = md; 392 393 #ifdef IPSEC 394 mh->m_pkthdr.rcvif = NULL; 395 #endif 396 mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld6_hdr); 397 mh->m_len = sizeof(struct ip6_hdr); 398 MH_ALIGN(mh, sizeof(struct ip6_hdr)); 399 400 /* fill in the ip6 header */ 401 ip6 = mtod(mh, struct ip6_hdr *); 402 ip6->ip6_flow = 0; 403 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 404 ip6->ip6_vfc |= IPV6_VERSION; 405 /* ip6_plen will be set later */ 406 ip6->ip6_nxt = IPPROTO_ICMPV6; 407 /* ip6_hlim will be set by im6o.im6o_multicast_hlim */ 408 ip6->ip6_src = ia->ia_addr.sin6_addr; 409 ip6->ip6_dst = dst ? *dst : in6m->in6m_addr; 410 411 /* fill in the MLD header */ 412 md->m_len = sizeof(struct mld6_hdr); 413 mldh = mtod(md, struct mld6_hdr *); 414 mldh->mld6_type = type; 415 mldh->mld6_code = 0; 416 mldh->mld6_cksum = 0; 417 /* XXX: we assume the function will not be called for query messages */ 418 mldh->mld6_maxdelay = 0; 419 mldh->mld6_reserved = 0; 420 mldh->mld6_addr = in6m->in6m_addr; 421 if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) 422 mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ 423 mldh->mld6_cksum = in6_cksum(mh, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), 424 sizeof(struct mld6_hdr)); 425 426 /* construct multicast option */ 427 bzero(&im6o, sizeof(im6o)); 428 im6o.im6o_multicast_ifp = ifp; 429 im6o.im6o_multicast_hlim = 1; 430 431 /* 432 * Request loopback of the report if we are acting as a multicast 433 * router, so that the process-level routing daemon can hear it. 434 */ 435 im6o.im6o_multicast_loop = (ip6_mrouter != NULL); 436 437 /* increment output statictics */ 438 icmp6stat.icp6s_outhist[type]++; 439 440 ip6_output(mh, &ip6_opts, NULL, 0, &im6o, &outif); 441 if (outif) { 442 icmp6_ifstat_inc(outif, ifs6_out_msg); 443 switch(type) { 444 case MLD6_LISTENER_QUERY: 445 icmp6_ifstat_inc(outif, ifs6_out_mldquery); 446 break; 447 case MLD6_LISTENER_REPORT: 448 icmp6_ifstat_inc(outif, ifs6_out_mldreport); 449 break; 450 case MLD6_LISTENER_DONE: 451 icmp6_ifstat_inc(outif, ifs6_out_mlddone); 452 break; 453 } 454 } 455 } 456
Indexes created Wed Oct 15 03:09:54 GMT 2025