/* $FreeBSD: src/sys/netinet6/mld6.c,v 1.4.2.2 2001/07/03 11:01:54 ume Exp $ */ /* $KAME: mld6.c,v 1.27 2001/04/04 05:17:30 itojun Exp $ */ /* * 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. */ /* * 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 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 <sys/param.h> #include <sys/systm.h> #include <sys/mbuf.h> #include <sys/socket.h> #include <sys/protosw.h> #include <sys/syslog.h> #include <net/if.h> #include <netinet/in.h> #include <netinet/in_var.h> #include <netinet/ip6.h> #include <netinet6/ip6_var.h> #include <netinet/icmp6.h> #include <netinet6/mld6_var.h> #include <net/net_osdep.h> /* * Protocol constants */ /* denotes that the MLD max response delay field specifies time in milliseconds */ #define MLD6_TIMER_SCALE 1000 /* * time between repetitions of a node's initial report of interest in a * multicast address(in seconds) */ #define MLD6_UNSOLICITED_REPORT_INTERVAL 10 static struct ip6_pktopts ip6_opts; static int mld6_timers_are_running; static int mld6_init_done = 0 ; /* XXX: These are necessary for KAME's link-local hack */ static struct in6_addr mld6_all_nodes_linklocal = IN6ADDR_LINKLOCAL_ALLNODES_INIT; static struct in6_addr mld6_all_routers_linklocal = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT; static void mld6_sendpkt __P((struct in6_multi *, int, const struct in6_addr *)); void mld6_init() { 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); if (mld6_init_done) return; mld6_init_done = 1; mld6_timers_are_running = 0; /* 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_RTALERT; hbh_buf[5] = IP6OPT_RTALERT_LEN - 2; bcopy((caddr_t)&rtalert_code, &hbh_buf[6], sizeof(u_int16_t)); init_ip6pktopts(&ip6_opts); ip6_opts.ip6po_hbh = hbh; } void mld6_start_listening(in6m) struct in6_multi *in6m; { 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). */ mld6_all_nodes_linklocal.s6_addr16[1] = htons(in6m->in6m_ifp->if_index); /* XXX */ if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal) || IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) { in6m->in6m_timer = 0; in6m->in6m_state = MLD6_OTHERLISTENER; } else { mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, NULL); in6m->in6m_timer = MLD6_RANDOM_DELAY( MLD6_UNSOLICITED_REPORT_INTERVAL * PR_FASTHZ); in6m->in6m_state = MLD6_IREPORTEDLAST; mld6_timers_are_running = 1; } splx(s); } void mld6_stop_listening(in6m) struct in6_multi *in6m; { mld6_all_nodes_linklocal.s6_addr16[1] = htons(in6m->in6m_ifp->if_index); /* XXX */ mld6_all_routers_linklocal.s6_addr16[1] = htons(in6m->in6m_ifp->if_index); /* XXX: necessary when mrouting */ if (in6m->in6m_state == MLD6_IREPORTEDLAST && (!IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &mld6_all_nodes_linklocal)) && IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) > IPV6_ADDR_SCOPE_NODELOCAL) mld6_sendpkt(in6m, MLD6_LISTENER_DONE, &mld6_all_routers_linklocal); } void mld6_input(m, off) struct mbuf *m; int off; { struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); struct mld6_hdr *mldh; struct ifnet *ifp = m->m_pkthdr.rcvif; struct in6_multi *in6m; struct in6_ifaddr *ia; struct ifmultiaddr *ifma; int timer; /* timer value in the MLD query header */ #ifndef PULLDOWN_TEST IP6_EXTHDR_CHECK(m, off, sizeof(*mldh),); mldh = (struct mld6_hdr *)(mtod(m, caddr_t) + off); #else IP6_EXTHDR_GET(mldh, struct mld6_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)) { log(LOG_ERR, "mld6_input: src %s is not link-local (grp=%s)\n", ip6_sprintf(&ip6->ip6_src), ip6_sprintf(&mldh->mld6_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; } /* * 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==0) * * The flag is in6m->in6m_state, it is set to MLD6_OTHERLISTENER if * we have heard a report from another member, or MLD6_IREPORTEDLAST * if we sent the last report. */ switch(mldh->mld6_type) { case MLD6_LISTENER_QUERY: if (ifp->if_flags & IFF_LOOPBACK) break; if (!IN6_IS_ADDR_UNSPECIFIED(&mldh->mld6_addr) && !IN6_IS_ADDR_MULTICAST(&mldh->mld6_addr)) break; /* print error or log stat? */ if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) mldh->mld6_addr.s6_addr16[1] = htons(ifp->if_index); /* XXX */ /* * - 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. */ 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->mld6_maxdelay)*PR_FASTHZ/MLD6_TIMER_SCALE; if (timer == 0 && mldh->mld6_maxdelay) timer = 1; mld6_all_nodes_linklocal.s6_addr16[1] = htons(ifp->if_index); /* XXX */ LIST_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, &mld6_all_nodes_linklocal) || IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) continue; if (IN6_IS_ADDR_UNSPECIFIED(&mldh->mld6_addr) || IN6_ARE_ADDR_EQUAL(&mldh->mld6_addr, &in6m->in6m_addr)) { if (timer == 0) { /* send a report immediately */ mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, NULL); in6m->in6m_timer = 0; /* reset timer */ in6m->in6m_state = MLD6_IREPORTEDLAST; } else if (in6m->in6m_timer == 0 || /*idle state*/ in6m->in6m_timer > timer) { in6m->in6m_timer = MLD6_RANDOM_DELAY(timer); mld6_timers_are_running = 1; } } } if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ break; case MLD6_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(&mldh->mld6_addr)) break; if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) mldh->mld6_addr.s6_addr16[1] = htons(ifp->if_index); /* XXX */ /* * If we belong to the group being reported, stop * our timer for that group. */ IN6_LOOKUP_MULTI(mldh->mld6_addr, ifp, in6m); if (in6m) { in6m->in6m_timer = 0; /* transit to idle state */ in6m->in6m_state = MLD6_OTHERLISTENER; /* clear flag */ } if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ break; default: /* this is impossible */ log(LOG_ERR, "mld6_input: illegal type(%d)", mldh->mld6_type); break; } m_freem(m); } void mld6_fasttimeo() { struct in6_multi *in6m; struct in6_multistep step; int s; /* * Quick check to see if any work needs to be done, in order * to minimize the overhead of fasttimo processing. */ if (!mld6_timers_are_running) return; s = splnet(); mld6_timers_are_running = 0; IN6_FIRST_MULTI(step, in6m); while (in6m != NULL) { if (in6m->in6m_timer == 0) { /* do nothing */ } else if (--in6m->in6m_timer == 0) { mld6_sendpkt(in6m, MLD6_LISTENER_REPORT, NULL); in6m->in6m_state = MLD6_IREPORTEDLAST; } else { mld6_timers_are_running = 1; } IN6_NEXT_MULTI(step, in6m); } splx(s); } static void mld6_sendpkt(in6m, type, dst) struct in6_multi *in6m; int type; const struct in6_addr *dst; { struct mbuf *mh, *md; struct mld6_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 mld6_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 mld6_hdr); mldh = mtod(md, struct mld6_hdr *); mldh->mld6_type = type; mldh->mld6_code = 0; mldh->mld6_cksum = 0; /* XXX: we assume the function will not be called for query messages */ mldh->mld6_maxdelay = 0; mldh->mld6_reserved = 0; mldh->mld6_addr = in6m->in6m_addr; if (IN6_IS_ADDR_MC_LINKLOCAL(&mldh->mld6_addr)) mldh->mld6_addr.s6_addr16[1] = 0; /* XXX */ mldh->mld6_cksum = in6_cksum(mh, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), sizeof(struct mld6_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); if (outif) { icmp6_ifstat_inc(outif, ifs6_out_msg); switch (type) { case MLD6_LISTENER_QUERY: icmp6_ifstat_inc(outif, ifs6_out_mldquery); break; case MLD6_LISTENER_REPORT: icmp6_ifstat_inc(outif, ifs6_out_mldreport); break; case MLD6_LISTENER_DONE: icmp6_ifstat_inc(outif, ifs6_out_mlddone); break; } } }