/*- * Copyright (C) 1998 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $KAME: mld6.c,v 1.27 2001/04/04 05:17:30 itojun Exp $ */ /*- * Copyright (c) 1988 Stephen Deering. * Copyright (c) 1992, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Stephen Deering of Stanford University. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)igmp.c 8.1 (Berkeley) 7/19/93 */ #include __FBSDID("$FreeBSD$"); #include "opt_inet.h" #include "opt_inet6.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Protocol constants */ /* denotes that the MLD max response delay field specifies time in milliseconds */ #define MLD_TIMER_SCALE 1000 /* * time between repetitions of a node's initial report of interest in a * multicast address(in seconds) */ #define MLD_UNSOLICITED_REPORT_INTERVAL 10 static struct ip6_pktopts ip6_opts; static void mld6_sendpkt(struct in6_multi *, int, const struct in6_addr *); static void mld_starttimer(struct in6_multi *); static void mld_stoptimer(struct in6_multi *); static void mld_timeo(struct in6_multi *); static u_long mld_timerresid(struct in6_multi *); void mld6_init(void) { static u_int8_t hbh_buf[8]; struct ip6_hbh *hbh = (struct ip6_hbh *)hbh_buf; u_int16_t rtalert_code = htons((u_int16_t)IP6OPT_RTALERT_MLD); /* ip6h_nxt will be fill in later */ hbh->ip6h_len = 0; /* (8 >> 3) - 1 */ /* XXX: grotty hard coding... */ hbh_buf[2] = IP6OPT_PADN; /* 2 byte padding */ hbh_buf[3] = 0; hbh_buf[4] = IP6OPT_ROUTER_ALERT; hbh_buf[5] = IP6OPT_RTALERT_LEN - 2; bcopy((caddr_t)&rtalert_code, &hbh_buf[6], sizeof(u_int16_t)); ip6_initpktopts(&ip6_opts); ip6_opts.ip6po_hbh = hbh; } static void mld_starttimer(struct in6_multi *in6m) { struct timeval now; microtime(&now); in6m->in6m_timer_expire.tv_sec = now.tv_sec + in6m->in6m_timer / hz; in6m->in6m_timer_expire.tv_usec = now.tv_usec + (in6m->in6m_timer % hz) * (1000000 / hz); if (in6m->in6m_timer_expire.tv_usec > 1000000) { in6m->in6m_timer_expire.tv_sec++; in6m->in6m_timer_expire.tv_usec -= 1000000; } /* start or restart the timer */ callout_reset(in6m->in6m_timer_ch, in6m->in6m_timer, (void (*)(void *))mld_timeo, in6m); } static void mld_stoptimer(struct in6_multi *in6m) { if (in6m->in6m_timer == IN6M_TIMER_UNDEF) return; callout_stop(in6m->in6m_timer_ch); in6m->in6m_timer = IN6M_TIMER_UNDEF; } static void mld_timeo(struct in6_multi *in6m) { int s = splnet(); in6m->in6m_timer = IN6M_TIMER_UNDEF; callout_stop(in6m->in6m_timer_ch); switch (in6m->in6m_state) { case MLD_REPORTPENDING: mld6_start_listening(in6m); break; default: mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL); break; } splx(s); } static u_long mld_timerresid(struct in6_multi *in6m) { struct timeval now, diff; microtime(&now); if (now.tv_sec > in6m->in6m_timer_expire.tv_sec || (now.tv_sec == in6m->in6m_timer_expire.tv_sec && now.tv_usec > in6m->in6m_timer_expire.tv_usec)) { return (0); } diff = in6m->in6m_timer_expire; diff.tv_sec -= now.tv_sec; diff.tv_usec -= now.tv_usec; if (diff.tv_usec < 0) { diff.tv_sec--; diff.tv_usec += 1000000; } /* return the remaining time in milliseconds */ return (diff.tv_sec * 1000 + diff.tv_usec / 1000); } void mld6_start_listening(struct in6_multi *in6m) { struct in6_addr all_in6; int s = splnet(); /* * RFC2710 page 10: * The node never sends a Report or Done for the link-scope all-nodes * address. * MLD messages are never sent for multicast addresses whose scope is 0 * (reserved) or 1 (node-local). */ all_in6 = in6addr_linklocal_allnodes; if (in6_setscope(&all_in6, in6m->in6m_ifp, NULL)) { /* XXX: this should not happen! */ in6m->in6m_timer = 0; in6m->in6m_state = MLD_OTHERLISTENER; } if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &all_in6) || IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) { in6m->in6m_timer = 0; in6m->in6m_state = MLD_OTHERLISTENER; } else { mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL); in6m->in6m_timer = arc4random() % MLD_UNSOLICITED_REPORT_INTERVAL * hz; in6m->in6m_state = MLD_IREPORTEDLAST; mld_starttimer(in6m); } splx(s); } void mld6_stop_listening(struct in6_multi *in6m) { struct in6_addr allnode, allrouter; allnode = in6addr_linklocal_allnodes; if (in6_setscope(&allnode, in6m->in6m_ifp, NULL)) { /* XXX: this should not happen! */ return; } allrouter = in6addr_linklocal_allrouters; if (in6_setscope(&allrouter, in6m->in6m_ifp, NULL)) { /* XXX impossible */ return; } if (in6m->in6m_state == MLD_IREPORTEDLAST && !IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &allnode) && IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) > IPV6_ADDR_SCOPE_INTFACELOCAL) { mld6_sendpkt(in6m, MLD_LISTENER_DONE, &allrouter); } } void mld6_input(struct mbuf *m, int off) { struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); struct mld_hdr *mldh; struct ifnet *ifp = m->m_pkthdr.rcvif; struct in6_multi *in6m; struct in6_addr mld_addr, all_in6; struct in6_ifaddr *ia; struct ifmultiaddr *ifma; u_long timer; /* timer value in the MLD query header */ #ifndef PULLDOWN_TEST IP6_EXTHDR_CHECK(m, off, sizeof(*mldh),); mldh = (struct mld_hdr *)(mtod(m, caddr_t) + off); #else IP6_EXTHDR_GET(mldh, struct mld_hdr *, m, off, sizeof(*mldh)); if (mldh == NULL) { icmp6stat.icp6s_tooshort++; return; } #endif /* source address validation */ ip6 = mtod(m, struct ip6_hdr *); /* in case mpullup */ if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) { char ip6bufs[INET6_ADDRSTRLEN], ip6bufg[INET6_ADDRSTRLEN]; log(LOG_ERR, "mld6_input: src %s is not link-local (grp=%s)\n", ip6_sprintf(ip6bufs, &ip6->ip6_src), ip6_sprintf(ip6bufg, &mldh->mld_addr)); /* * spec (RFC2710) does not explicitly * specify to discard the packet from a non link-local * source address. But we believe it's expected to do so. * XXX: do we have to allow :: as source? */ m_freem(m); return; } /* * make a copy for local work (in6_setscope() may modify the 1st arg) */ mld_addr = mldh->mld_addr; if (in6_setscope(&mld_addr, ifp, NULL)) { /* XXX: this should not happen! */ m_free(m); return; } /* * In the MLD6 specification, there are 3 states and a flag. * * In Non-Listener state, we simply don't have a membership record. * In Delaying Listener state, our timer is running (in6m->in6m_timer) * In Idle Listener state, our timer is not running * (in6m->in6m_timer==IN6M_TIMER_UNDEF) * * The flag is in6m->in6m_state, it is set to MLD_OTHERLISTENER if * we have heard a report from another member, or MLD_IREPORTEDLAST * if we sent the last report. */ switch(mldh->mld_type) { case MLD_LISTENER_QUERY: if (ifp->if_flags & IFF_LOOPBACK) break; if (!IN6_IS_ADDR_UNSPECIFIED(&mld_addr) && !IN6_IS_ADDR_MULTICAST(&mld_addr)) break; /* print error or log stat? */ all_in6 = in6addr_linklocal_allnodes; if (in6_setscope(&all_in6, ifp, NULL)) { /* XXX: this should not happen! */ break; } /* * - Start the timers in all of our membership records * that the query applies to for the interface on * which the query arrived excl. those that belong * to the "all-nodes" group (ff02::1). * - Restart any timer that is already running but has * A value longer than the requested timeout. * - Use the value specified in the query message as * the maximum timeout. */ timer = ntohs(mldh->mld_maxdelay); IFP_TO_IA6(ifp, ia); if (ia == NULL) break; /* * XXX: System timer resolution is too low to handle Max * Response Delay, so set 1 to the internal timer even if * the calculated value equals to zero when Max Response * Delay is positive. */ timer = ntohs(mldh->mld_maxdelay) * PR_FASTHZ / MLD_TIMER_SCALE; if (timer == 0 && mldh->mld_maxdelay) timer = 1; IF_ADDR_LOCK(ifp); TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) { if (ifma->ifma_addr->sa_family != AF_INET6) continue; in6m = (struct in6_multi *)ifma->ifma_protospec; if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &all_in6) || IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) continue; if (IN6_IS_ADDR_UNSPECIFIED(&mld_addr) || IN6_ARE_ADDR_EQUAL(&mld_addr, &in6m->in6m_addr)) { if (timer == 0) { /* send a report immediately */ mld_stoptimer(in6m); mld6_sendpkt(in6m, MLD_LISTENER_REPORT, NULL); in6m->in6m_timer = 0; /* reset timer */ in6m->in6m_state = MLD_IREPORTEDLAST; } else if (in6m->in6m_timer == IN6M_TIMER_UNDEF || mld_timerresid(in6m) > timer) { in6m->in6m_timer = 1 + (arc4random() % timer) * hz / 1000; mld_starttimer(in6m); } } } IF_ADDR_UNLOCK(ifp); break; case MLD_LISTENER_REPORT: /* * For fast leave to work, we have to know that we are the * last person to send a report for this group. Reports * can potentially get looped back if we are a multicast * router, so discard reports sourced by me. * Note that it is impossible to check IFF_LOOPBACK flag of * ifp for this purpose, since ip6_mloopback pass the physical * interface to looutput. */ if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */ break; if (!IN6_IS_ADDR_MULTICAST(&mld_addr)) break; /* * If we belong to the group being reported, stop * our timer for that group. */ IN6_LOOKUP_MULTI(mld_addr, ifp, in6m); if (in6m) { in6m->in6m_timer = 0; /* transit to idle state */ in6m->in6m_state = MLD_OTHERLISTENER; /* clear flag */ } break; default: /* this is impossible */ log(LOG_ERR, "mld6_input: illegal type(%d)", mldh->mld_type); break; } m_freem(m); } static void mld6_sendpkt(struct in6_multi *in6m, int type, const struct in6_addr *dst) { struct mbuf *mh, *md; struct mld_hdr *mldh; struct ip6_hdr *ip6; struct ip6_moptions im6o; struct in6_ifaddr *ia; struct ifnet *ifp = in6m->in6m_ifp; struct ifnet *outif = NULL; /* * At first, find a link local address on the outgoing interface * to use as the source address of the MLD packet. */ if ((ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST)) == NULL) return; /* * Allocate mbufs to store ip6 header and MLD header. * We allocate 2 mbufs and make chain in advance because * it is more convenient when inserting the hop-by-hop option later. */ MGETHDR(mh, M_DONTWAIT, MT_HEADER); if (mh == NULL) return; MGET(md, M_DONTWAIT, MT_DATA); if (md == NULL) { m_free(mh); return; } mh->m_next = md; mh->m_pkthdr.rcvif = NULL; mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld_hdr); mh->m_len = sizeof(struct ip6_hdr); MH_ALIGN(mh, sizeof(struct ip6_hdr)); /* fill in the ip6 header */ ip6 = mtod(mh, struct ip6_hdr *); ip6->ip6_flow = 0; ip6->ip6_vfc &= ~IPV6_VERSION_MASK; ip6->ip6_vfc |= IPV6_VERSION; /* ip6_plen will be set later */ ip6->ip6_nxt = IPPROTO_ICMPV6; /* ip6_hlim will be set by im6o.im6o_multicast_hlim */ ip6->ip6_src = ia->ia_addr.sin6_addr; ip6->ip6_dst = dst ? *dst : in6m->in6m_addr; /* fill in the MLD header */ md->m_len = sizeof(struct mld_hdr); mldh = mtod(md, struct mld_hdr *); mldh->mld_type = type; mldh->mld_code = 0; mldh->mld_cksum = 0; /* XXX: we assume the function will not be called for query messages */ mldh->mld_maxdelay = 0; mldh->mld_reserved = 0; mldh->mld_addr = in6m->in6m_addr; in6_clearscope(&mldh->mld_addr); /* XXX */ mldh->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), sizeof(struct mld_hdr)); /* construct multicast option */ bzero(&im6o, sizeof(im6o)); im6o.im6o_multicast_ifp = ifp; im6o.im6o_multicast_hlim = 1; /* * Request loopback of the report if we are acting as a multicast * router, so that the process-level routing daemon can hear it. */ im6o.im6o_multicast_loop = (ip6_mrouter != NULL); /* increment output statictics */ icmp6stat.icp6s_outhist[type]++; ip6_output(mh, &ip6_opts, NULL, 0, &im6o, &outif, NULL); if (outif) { icmp6_ifstat_inc(outif, ifs6_out_msg); switch (type) { case MLD_LISTENER_QUERY: icmp6_ifstat_inc(outif, ifs6_out_mldquery); break; case MLD_LISTENER_REPORT: icmp6_ifstat_inc(outif, ifs6_out_mldreport); break; case MLD_LISTENER_DONE: icmp6_ifstat_inc(outif, ifs6_out_mlddone); break; } } } /* * Add an address to the list of IP6 multicast addresses for a given interface. * Add source addresses to the list also, if upstream router is MLDv2 capable * and the number of source is not 0. */ struct in6_multi * in6_addmulti(struct in6_addr *maddr6, struct ifnet *ifp, int *errorp, int delay) { struct in6_multi *in6m; *errorp = 0; in6m = NULL; IFF_LOCKGIANT(ifp); /*IN6_MULTI_LOCK();*/ IN6_LOOKUP_MULTI(*maddr6, ifp, in6m); if (in6m != NULL) { /* * If we already joined this group, just bump the * refcount and return it. */ KASSERT(in6m->in6m_refcount >= 1, ("%s: bad refcount %d", __func__, in6m->in6m_refcount)); ++in6m->in6m_refcount; } else do { struct in6_multi *nin6m; struct ifmultiaddr *ifma; struct sockaddr_in6 sa6; bzero(&sa6, sizeof(sa6)); sa6.sin6_family = AF_INET6; sa6.sin6_len = sizeof(struct sockaddr_in6); sa6.sin6_addr = *maddr6; *errorp = if_addmulti(ifp, (struct sockaddr *)&sa6, &ifma); if (*errorp) break; /* * If ifma->ifma_protospec is null, then if_addmulti() created * a new record. Otherwise, bump refcount, and we are done. */ if (ifma->ifma_protospec != NULL) { in6m = ifma->ifma_protospec; ++in6m->in6m_refcount; break; } nin6m = malloc(sizeof(*nin6m), M_IP6MADDR, M_NOWAIT | M_ZERO); if (nin6m == NULL) { if_delmulti_ifma(ifma); break; } nin6m->in6m_addr = *maddr6; nin6m->in6m_ifp = ifp; nin6m->in6m_refcount = 1; nin6m->in6m_ifma = ifma; ifma->ifma_protospec = nin6m; nin6m->in6m_timer_ch = malloc(sizeof(*nin6m->in6m_timer_ch), M_IP6MADDR, M_NOWAIT); if (nin6m->in6m_timer_ch == NULL) { free(nin6m, M_IP6MADDR); if_delmulti_ifma(ifma); break; } LIST_INSERT_HEAD(&in6_multihead, nin6m, in6m_entry); callout_init(nin6m->in6m_timer_ch, 0); nin6m->in6m_timer = delay; if (nin6m->in6m_timer > 0) { nin6m->in6m_state = MLD_REPORTPENDING; mld_starttimer(nin6m); } mld6_start_listening(nin6m); in6m = nin6m; } while (0); /*IN6_MULTI_UNLOCK();*/ IFF_UNLOCKGIANT(ifp); return (in6m); } /* * Delete a multicast address record. * * TODO: Locking, as per netinet. */ void in6_delmulti(struct in6_multi *in6m) { struct ifmultiaddr *ifma; KASSERT(in6m->in6m_refcount >= 1, ("%s: freeing freed in6m", __func__)); if (--in6m->in6m_refcount == 0) { mld_stoptimer(in6m); mld6_stop_listening(in6m); ifma = in6m->in6m_ifma; KASSERT(ifma->ifma_protospec == in6m, ("%s: ifma_protospec != in6m", __func__)); ifma->ifma_protospec = NULL; LIST_REMOVE(in6m, in6m_entry); free(in6m->in6m_timer_ch, M_IP6MADDR); free(in6m, M_IP6MADDR); if_delmulti_ifma(ifma); } }