[BACK]Return to mld6.c CVS log [TXT][DIR] Up to [cvs.NetBSD.org] / src / sys / netinet6

Annotation of src/sys/netinet6/mld6.c, Revision 1.30

1.30    ! rpaulo      1: /*     $NetBSD: mld6.c,v 1.29 2006/01/21 00:15:36 rpaulo Exp $ */
1.13      itojun      2: /*     $KAME: mld6.c,v 1.25 2001/01/16 14:14:18 itojun Exp $   */
1.3       thorpej     3:
1.2       itojun      4: /*
                      5:  * Copyright (C) 1998 WIDE Project.
                      6:  * All rights reserved.
1.13      itojun      7:  *
1.2       itojun      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.
1.13      itojun     19:  *
1.2       itojun     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.
1.23      agc        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.
1.2       itojun     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:  */
1.16      lukem     103:
                    104: #include <sys/cdefs.h>
1.30    ! rpaulo    105: __KERNEL_RCSID(0, "$NetBSD: mld6.c,v 1.29 2006/01/21 00:15:36 rpaulo Exp $");
1.2       itojun    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>
1.10      itojun    120: #include <netinet/ip6.h>
1.2       itojun    121: #include <netinet6/ip6_var.h>
1.29      rpaulo    122: #include <netinet6/scope6_var.h>
1.10      itojun    123: #include <netinet/icmp6.h>
1.2       itojun    124: #include <netinet6/mld6_var.h>
                    125:
1.7       itojun    126: #include <net/net_osdep.h>
                    127:
1.2       itojun    128: /*
                    129:  * Protocol constants
                    130:  */
                    131:
                    132: /* denotes that the MLD max response delay field specifies time in milliseconds */
1.22      itojun    133: #define MLD_TIMER_SCALE        1000
1.2       itojun    134: /*
                    135:  * time between repetitions of a node's initial report of interest in a
                    136:  * multicast address(in seconds)
                    137:  */
1.22      itojun    138: #define MLD_UNSOLICITED_REPORT_INTERVAL        10
1.2       itojun    139:
                    140: static struct ip6_pktopts ip6_opts;
1.22      itojun    141: static int mld_timers_are_running;
1.2       itojun    142:
                    143: static void mld6_sendpkt __P((struct in6_multi *, int, const struct in6_addr *));
                    144:
                    145: void
                    146: mld6_init()
                    147: {
                    148:        static u_int8_t hbh_buf[8];
                    149:        struct ip6_hbh *hbh = (struct ip6_hbh *)hbh_buf;
                    150:        u_int16_t rtalert_code = htons((u_int16_t)IP6OPT_RTALERT_MLD);
                    151:
1.22      itojun    152:        mld_timers_are_running = 0;
1.2       itojun    153:
                    154:        /* ip6h_nxt will be fill in later */
1.11      itojun    155:        hbh->ip6h_len = 0;      /* (8 >> 3) - 1 */
1.2       itojun    156:
                    157:        /* XXX: grotty hard coding... */
                    158:        hbh_buf[2] = IP6OPT_PADN;       /* 2 byte padding */
                    159:        hbh_buf[3] = 0;
                    160:        hbh_buf[4] = IP6OPT_RTALERT;
                    161:        hbh_buf[5] = IP6OPT_RTALERT_LEN - 2;
                    162:        bcopy((caddr_t)&rtalert_code, &hbh_buf[6], sizeof(u_int16_t));
                    163:
                    164:        ip6_opts.ip6po_hbh = hbh;
                    165:        /* We will specify the hoplimit by a multicast option. */
                    166:        ip6_opts.ip6po_hlim = -1;
                    167: }
                    168:
                    169: void
                    170: mld6_start_listening(in6m)
                    171:        struct in6_multi *in6m;
                    172: {
1.29      rpaulo    173:        struct in6_addr all_in6;
                    174:
1.2       itojun    175:        /*
1.11      itojun    176:         * RFC2710 page 10:
1.2       itojun    177:         * The node never sends a Report or Done for the link-scope all-nodes
                    178:         * address.
                    179:         * MLD messages are never sent for multicast addresses whose scope is 0
                    180:         * (reserved) or 1 (node-local).
                    181:         */
1.29      rpaulo    182:        all_in6 = in6addr_linklocal_allnodes;
                    183:        if (in6_setscope(&all_in6, in6m->in6m_ifp, NULL)) {
                    184:                /* XXX: this should not happen! */
                    185:                in6m->in6m_timer = 0;
                    186:                in6m->in6m_state = MLD_OTHERLISTENER;
                    187:        }
                    188:        if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &all_in6) ||
1.2       itojun    189:            IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) {
                    190:                in6m->in6m_timer = 0;
1.22      itojun    191:                in6m->in6m_state = MLD_OTHERLISTENER;
1.2       itojun    192:        } else {
1.22      itojun    193:                mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
1.19      itojun    194:                in6m->in6m_timer =
1.22      itojun    195:                    MLD_RANDOM_DELAY(MLD_UNSOLICITED_REPORT_INTERVAL *
1.19      itojun    196:                    PR_FASTHZ);
1.22      itojun    197:                in6m->in6m_state = MLD_IREPORTEDLAST;
                    198:                mld_timers_are_running = 1;
1.2       itojun    199:        }
                    200: }
                    201:
                    202: void
                    203: mld6_stop_listening(in6m)
                    204:        struct in6_multi *in6m;
                    205: {
1.29      rpaulo    206:        struct in6_addr allnode, allrouter;
                    207:
                    208:        allnode = in6addr_linklocal_allnodes;
                    209:        if (in6_setscope(&allnode, in6m->in6m_ifp, NULL)) {
                    210:                /* XXX: this should not happen! */
                    211:                return;
                    212:        }
                    213:        allrouter = in6addr_linklocal_allrouters;
                    214:        if (in6_setscope(&allrouter, in6m->in6m_ifp, NULL)) {
                    215:                /* XXX impossible */
                    216:                return;
                    217:        }
1.2       itojun    218:
1.22      itojun    219:        if (in6m->in6m_state == MLD_IREPORTEDLAST &&
1.29      rpaulo    220:            (!IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &allnode)) &&
                    221:            IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) >
                    222:            IPV6_ADDR_SCOPE_INTFACELOCAL) {
                    223:                mld6_sendpkt(in6m, MLD_LISTENER_DONE, &allrouter);
                    224:        }
1.2       itojun    225: }
                    226:
                    227: void
                    228: mld6_input(m, off)
                    229:        struct mbuf *m;
                    230:        int off;
                    231: {
                    232:        struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1.22      itojun    233:        struct mld_hdr *mldh;
1.2       itojun    234:        struct ifnet *ifp = m->m_pkthdr.rcvif;
                    235:        struct in6_multi *in6m;
1.29      rpaulo    236:        struct in6_addr mld_addr, all_in6;
1.2       itojun    237:        struct in6_ifaddr *ia;
                    238:        int timer;              /* timer value in the MLD query header */
                    239:
1.22      itojun    240:        IP6_EXTHDR_GET(mldh, struct mld_hdr *, m, off, sizeof(*mldh));
1.13      itojun    241:        if (mldh == NULL) {
                    242:                icmp6stat.icp6s_tooshort++;
                    243:                return;
                    244:        }
                    245:
1.2       itojun    246:        /* source address validation */
1.13      itojun    247:        ip6 = mtod(m, struct ip6_hdr *);/* in case mpullup */
1.2       itojun    248:        if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) {
1.18      itojun    249: #if 0
1.2       itojun    250:                log(LOG_ERR,
1.22      itojun    251:                    "mld_input: src %s is not link-local (grp=%s)\n",
1.13      itojun    252:                    ip6_sprintf(&ip6->ip6_src),
1.22      itojun    253:                    ip6_sprintf(&mldh->mld_addr));
1.18      itojun    254: #endif
1.2       itojun    255:                /*
1.11      itojun    256:                 * spec (RFC2710) does not explicitly
1.2       itojun    257:                 * specify to discard the packet from a non link-local
                    258:                 * source address. But we believe it's expected to do so.
1.13      itojun    259:                 * XXX: do we have to allow :: as source?
1.2       itojun    260:                 */
1.11      itojun    261:                m_freem(m);
1.2       itojun    262:                return;
                    263:        }
                    264:
                    265:        /*
1.29      rpaulo    266:         * make a copy for local work (in6_setscope() may modify the 1st arg)
                    267:         */
                    268:        mld_addr = mldh->mld_addr;
                    269:        if (in6_setscope(&mld_addr, ifp, NULL)) {
                    270:                /* XXX: this should not happen! */
                    271:                m_free(m);
                    272:                return;
                    273:        }
                    274:
                    275:        /*
1.2       itojun    276:         * In the MLD6 specification, there are 3 states and a flag.
                    277:         *
                    278:         * In Non-Listener state, we simply don't have a membership record.
                    279:         * In Delaying Listener state, our timer is running (in6m->in6m_timer)
                    280:         * In Idle Listener state, our timer is not running (in6m->in6m_timer==0)
                    281:         *
1.22      itojun    282:         * The flag is in6m->in6m_state, it is set to MLD_OTHERLISTENER if
                    283:         * we have heard a report from another member, or MLD_IREPORTEDLAST
1.2       itojun    284:         * if we sent the last report.
                    285:         */
1.22      itojun    286:        switch (mldh->mld_type) {
                    287:        case MLD_LISTENER_QUERY:
1.7       itojun    288:                if (ifp->if_flags & IFF_LOOPBACK)
                    289:                        break;
                    290:
1.29      rpaulo    291:                if (!IN6_IS_ADDR_UNSPECIFIED(&mld_addr) &&
                    292:                    !IN6_IS_ADDR_MULTICAST(&mld_addr))
1.7       itojun    293:                        break;  /* print error or log stat? */
1.29      rpaulo    294:
                    295:                all_in6 = in6addr_linklocal_allnodes;
                    296:                if (in6_setscope(&all_in6, ifp, NULL)) {
                    297:                        /* XXX: this should not happen! */
                    298:                        break;
                    299:                }
1.2       itojun    300:
1.7       itojun    301:                /*
1.11      itojun    302:                 * - Start the timers in all of our membership records
                    303:                 *   that the query applies to for the interface on
                    304:                 *   which the query arrived excl. those that belong
                    305:                 *   to the "all-nodes" group (ff02::1).
                    306:                 * - Restart any timer that is already running but has
1.30    ! rpaulo    307:                 *   a value longer than the requested timeout.
1.11      itojun    308:                 * - Use the value specified in the query message as
                    309:                 *   the maximum timeout.
                    310:                 */
1.7       itojun    311:                IFP_TO_IA6(ifp, ia);
                    312:                if (ia == NULL)
                    313:                        break;
1.2       itojun    314:
                    315:                /*
1.11      itojun    316:                 * XXX: System timer resolution is too low to handle Max
                    317:                 * Response Delay, so set 1 to the internal timer even if
                    318:                 * the calculated value equals to zero when Max Response
                    319:                 * Delay is positive.
                    320:                 */
1.22      itojun    321:                timer = ntohs(mldh->mld_maxdelay)*PR_FASTHZ/MLD_TIMER_SCALE;
                    322:                if (timer == 0 && mldh->mld_maxdelay)
1.7       itojun    323:                        timer = 1;
1.20      itojun    324:
1.7       itojun    325:                for (in6m = ia->ia6_multiaddrs.lh_first;
                    326:                     in6m;
                    327:                     in6m = in6m->in6m_entry.le_next)
                    328:                {
1.29      rpaulo    329:                        if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &all_in6) ||
1.7       itojun    330:                            IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) <
                    331:                            IPV6_ADDR_SCOPE_LINKLOCAL)
                    332:                                continue;
1.2       itojun    333:
1.29      rpaulo    334:                        if (IN6_IS_ADDR_UNSPECIFIED(&mld_addr) ||
                    335:                            IN6_ARE_ADDR_EQUAL(&mld_addr, &in6m->in6m_addr)) {
1.7       itojun    336:                                if (timer == 0) {
                    337:                                        /* send a report immediately */
1.22      itojun    338:                                        mld6_sendpkt(in6m, MLD_LISTENER_REPORT,
1.19      itojun    339:                                            NULL);
1.7       itojun    340:                                        in6m->in6m_timer = 0; /* reset timer */
1.22      itojun    341:                                        in6m->in6m_state = MLD_IREPORTEDLAST;
1.7       itojun    342:                                }
                    343:                                else if (in6m->in6m_timer == 0 || /*idle state*/
1.19      itojun    344:                                    in6m->in6m_timer > timer) {
1.7       itojun    345:                                        in6m->in6m_timer =
1.22      itojun    346:                                            MLD_RANDOM_DELAY(timer);
                    347:                                        mld_timers_are_running = 1;
1.7       itojun    348:                                }
                    349:                        }
                    350:                }
1.29      rpaulo    351:                break;
1.2       itojun    352:
1.22      itojun    353:        case MLD_LISTENER_REPORT:
1.2       itojun    354:                /*
1.11      itojun    355:                 * For fast leave to work, we have to know that we are the
                    356:                 * last person to send a report for this group.  Reports
                    357:                 * can potentially get looped back if we are a multicast
                    358:                 * router, so discard reports sourced by me.
                    359:                 * Note that it is impossible to check IFF_LOOPBACK flag of
                    360:                 * ifp for this purpose, since ip6_mloopback pass the physical
                    361:                 * interface to looutput.
                    362:                 */
1.7       itojun    363:                if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */
                    364:                        break;
                    365:
1.22      itojun    366:                if (!IN6_IS_ADDR_MULTICAST(&mldh->mld_addr))
1.7       itojun    367:                        break;
                    368:
                    369:                /*
1.11      itojun    370:                 * If we belong to the group being reported, stop
                    371:                 * our timer for that group.
                    372:                 */
1.29      rpaulo    373:                IN6_LOOKUP_MULTI(mld_addr, ifp, in6m);
1.7       itojun    374:                if (in6m) {
                    375:                        in6m->in6m_timer = 0; /* transit to idle state */
1.22      itojun    376:                        in6m->in6m_state = MLD_OTHERLISTENER; /* clear flag */
1.7       itojun    377:                }
                    378:                break;
                    379:        default:                /* this is impossible */
1.18      itojun    380: #if 0
1.19      itojun    381:                /*
                    382:                 * this case should be impossible because of filtering in
                    383:                 * icmp6_input().  But we explicitly disabled this part
                    384:                 * just in case.
                    385:                 */
1.22      itojun    386:                log(LOG_ERR, "mld_input: illegal type(%d)", mldh->mld6_type);
1.18      itojun    387: #endif
1.7       itojun    388:                break;
1.2       itojun    389:        }
1.11      itojun    390:
                    391:        m_freem(m);
1.2       itojun    392: }
                    393:
                    394: void
                    395: mld6_fasttimeo()
                    396: {
1.13      itojun    397:        struct in6_multi *in6m;
1.2       itojun    398:        struct in6_multistep step;
                    399:        int s;
                    400:        /*
                    401:         * Quick check to see if any work needs to be done, in order
                    402:         * to minimize the overhead of fasttimo processing.
                    403:         */
1.22      itojun    404:        if (!mld_timers_are_running)
1.2       itojun    405:                return;
                    406:
1.4       itojun    407:        s = splsoftnet();
1.22      itojun    408:        mld_timers_are_running = 0;
1.2       itojun    409:        IN6_FIRST_MULTI(step, in6m);
                    410:        while (in6m != NULL) {
                    411:                if (in6m->in6m_timer == 0) {
                    412:                        /* do nothing */
                    413:                } else if (--in6m->in6m_timer == 0) {
1.22      itojun    414:                        mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
                    415:                        in6m->in6m_state = MLD_IREPORTEDLAST;
1.2       itojun    416:                } else {
1.22      itojun    417:                        mld_timers_are_running = 1;
1.2       itojun    418:                }
                    419:                IN6_NEXT_MULTI(step, in6m);
                    420:        }
                    421:        splx(s);
                    422: }
                    423:
                    424: static void
                    425: mld6_sendpkt(in6m, type, dst)
                    426:        struct in6_multi *in6m;
                    427:        int type;
                    428:        const struct in6_addr *dst;
                    429: {
                    430:        struct mbuf *mh, *md;
1.22      itojun    431:        struct mld_hdr *mldh;
1.2       itojun    432:        struct ip6_hdr *ip6;
                    433:        struct ip6_moptions im6o;
                    434:        struct in6_ifaddr *ia;
                    435:        struct ifnet *ifp = in6m->in6m_ifp;
1.19      itojun    436:        int ignflags;
1.2       itojun    437:
                    438:        /*
                    439:         * At first, find a link local address on the outgoing interface
                    440:         * to use as the source address of the MLD packet.
1.19      itojun    441:         * We do not reject tentative addresses for MLD report to deal with
                    442:         * the case where we first join a link-local address.
1.2       itojun    443:         */
1.19      itojun    444:        ignflags = (IN6_IFF_NOTREADY|IN6_IFF_ANYCAST) & ~IN6_IFF_TENTATIVE;
                    445:        if ((ia = in6ifa_ifpforlinklocal(ifp, ignflags)) == NULL)
1.2       itojun    446:                return;
1.19      itojun    447:        if ((ia->ia6_flags & IN6_IFF_TENTATIVE))
                    448:                ia = NULL;
1.2       itojun    449:
                    450:        /*
                    451:         * Allocate mbufs to store ip6 header and MLD header.
                    452:         * We allocate 2 mbufs and make chain in advance because
                    453:         * it is more convenient when inserting the hop-by-hop option later.
                    454:         */
                    455:        MGETHDR(mh, M_DONTWAIT, MT_HEADER);
                    456:        if (mh == NULL)
                    457:                return;
                    458:        MGET(md, M_DONTWAIT, MT_DATA);
                    459:        if (md == NULL) {
                    460:                m_free(mh);
                    461:                return;
                    462:        }
                    463:        mh->m_next = md;
                    464:
1.19      itojun    465:        mh->m_pkthdr.rcvif = NULL;
1.22      itojun    466:        mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld_hdr);
1.2       itojun    467:        mh->m_len = sizeof(struct ip6_hdr);
                    468:        MH_ALIGN(mh, sizeof(struct ip6_hdr));
                    469:
                    470:        /* fill in the ip6 header */
                    471:        ip6 = mtod(mh, struct ip6_hdr *);
                    472:        ip6->ip6_flow = 0;
1.8       itojun    473:        ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
                    474:        ip6->ip6_vfc |= IPV6_VERSION;
1.2       itojun    475:        /* ip6_plen will be set later */
                    476:        ip6->ip6_nxt = IPPROTO_ICMPV6;
                    477:        /* ip6_hlim will be set by im6o.im6o_multicast_hlim */
1.19      itojun    478:        ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
1.2       itojun    479:        ip6->ip6_dst = dst ? *dst : in6m->in6m_addr;
                    480:
                    481:        /* fill in the MLD header */
1.22      itojun    482:        md->m_len = sizeof(struct mld_hdr);
                    483:        mldh = mtod(md, struct mld_hdr *);
                    484:        mldh->mld_type = type;
                    485:        mldh->mld_code = 0;
                    486:        mldh->mld_cksum = 0;
1.2       itojun    487:        /* XXX: we assume the function will not be called for query messages */
1.22      itojun    488:        mldh->mld_maxdelay = 0;
                    489:        mldh->mld_reserved = 0;
                    490:        mldh->mld_addr = in6m->in6m_addr;
1.29      rpaulo    491:        in6_clearscope(&mldh->mld_addr); /* XXX */
1.22      itojun    492:        mldh->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6, sizeof(struct ip6_hdr),
                    493:            sizeof(struct mld_hdr));
1.2       itojun    494:
                    495:        /* construct multicast option */
                    496:        bzero(&im6o, sizeof(im6o));
                    497:        im6o.im6o_multicast_ifp = ifp;
                    498:        im6o.im6o_multicast_hlim = 1;
                    499:
                    500:        /*
                    501:         * Request loopback of the report if we are acting as a multicast
                    502:         * router, so that the process-level routing daemon can hear it.
                    503:         */
                    504:        im6o.im6o_multicast_loop = (ip6_mrouter != NULL);
                    505:
                    506:        /* increment output statictics */
                    507:        icmp6stat.icp6s_outhist[type]++;
1.15      itojun    508:        icmp6_ifstat_inc(ifp, ifs6_out_msg);
1.17      itojun    509:        switch (type) {
1.22      itojun    510:        case MLD_LISTENER_QUERY:
1.15      itojun    511:                icmp6_ifstat_inc(ifp, ifs6_out_mldquery);
                    512:                break;
1.22      itojun    513:        case MLD_LISTENER_REPORT:
1.15      itojun    514:                icmp6_ifstat_inc(ifp, ifs6_out_mldreport);
                    515:                break;
1.22      itojun    516:        case MLD_LISTENER_DONE:
1.15      itojun    517:                icmp6_ifstat_inc(ifp, ifs6_out_mlddone);
                    518:                break;
1.7       itojun    519:        }
1.19      itojun    520:
1.27      perry     521:        ip6_output(mh, &ip6_opts, NULL, ia ? 0 : IPV6_UNSPECSRC,
1.25      itojun    522:            &im6o, (struct socket *)NULL, NULL);
1.2       itojun    523: }

CVSweb <webmaster@jp.NetBSD.org>