/* $NetBSD: mld6.c,v 1.89.2.2 2018/06/07 17:48:31 martin Exp $ */ /* $KAME: mld6.c,v 1.25 2001/01/16 14:14:18 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) 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. 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 */ /* * Copyright (c) 1988 Stephen Deering. * * 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 __KERNEL_RCSID(0, "$NetBSD: mld6.c,v 1.89.2.2 2018/06/07 17:48:31 martin Exp $"); #ifdef _KERNEL_OPT #include "opt_inet.h" #include "opt_net_mpsafe.h" #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static krwlock_t in6_multilock __cacheline_aligned; /* * Protocol constants */ /* * 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 mld_start_listening(struct in6_multi *); static void mld_stop_listening(struct in6_multi *); static struct mld_hdr * mld_allocbuf(struct mbuf **, int, struct in6_multi *, int); static void mld_sendpkt(struct in6_multi *, int, const struct in6_addr *); static void mld_starttimer(struct in6_multi *); static void mld_stoptimer(struct in6_multi *); static u_long mld_timerresid(struct in6_multi *); static void in6m_ref(struct in6_multi *); static void in6m_unref(struct in6_multi *); static void in6m_destroy(struct in6_multi *); void mld_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_RTALERT; hbh_buf[5] = IP6OPT_RTALERT_LEN - 2; memcpy(&hbh_buf[6], (void *)&rtalert_code, sizeof(u_int16_t)); ip6_opts.ip6po_hbh = hbh; /* We will specify the hoplimit by a multicast option. */ ip6_opts.ip6po_hlim = -1; ip6_opts.ip6po_prefer_tempaddr = IP6PO_TEMPADDR_NOTPREFER; rw_init(&in6_multilock); } static void mld_starttimer(struct in6_multi *in6m) { struct timeval now; KASSERT(rw_write_held(&in6_multilock)); KASSERT(in6m->in6m_timer != IN6M_TIMER_UNDEF); 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_schedule(&in6m->in6m_timer_ch, in6m->in6m_timer); } /* * mld_stoptimer releases in6_multilock when calling callout_halt. * The caller must ensure in6m won't be freed while releasing the lock. */ static void mld_stoptimer(struct in6_multi *in6m) { KASSERT(rw_write_held(&in6_multilock)); if (in6m->in6m_timer == IN6M_TIMER_UNDEF) return; rw_exit(&in6_multilock); callout_halt(&in6m->in6m_timer_ch, NULL); rw_enter(&in6_multilock, RW_WRITER); in6m->in6m_timer = IN6M_TIMER_UNDEF; } static void mld_timeo(void *arg) { struct in6_multi *in6m = arg; KASSERT(in6m->in6m_refcount > 0); KERNEL_LOCK_UNLESS_NET_MPSAFE(); rw_enter(&in6_multilock, RW_WRITER); if (in6m->in6m_timer == IN6M_TIMER_UNDEF) goto out; in6m->in6m_timer = IN6M_TIMER_UNDEF; switch (in6m->in6m_state) { case MLD_REPORTPENDING: mld_start_listening(in6m); break; default: mld_sendpkt(in6m, MLD_LISTENER_REPORT, NULL); break; } out: rw_exit(&in6_multilock); KERNEL_UNLOCK_UNLESS_NET_MPSAFE(); } 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; } static void mld_start_listening(struct in6_multi *in6m) { struct in6_addr all_in6; KASSERT(rw_write_held(&in6_multilock)); /* * 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 = IN6M_TIMER_UNDEF; in6m->in6m_state = MLD_OTHERLISTENER; } else { mld_sendpkt(in6m, MLD_LISTENER_REPORT, NULL); in6m->in6m_timer = cprng_fast32() % (MLD_UNSOLICITED_REPORT_INTERVAL * hz); in6m->in6m_state = MLD_IREPORTEDLAST; mld_starttimer(in6m); } } static void mld_stop_listening(struct in6_multi *in6m) { struct in6_addr allnode, allrouter; KASSERT(rw_lock_held(&in6_multilock)); 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) { mld_sendpkt(in6m, MLD_LISTENER_DONE, &allrouter); } } void mld_input(struct mbuf *m, int off) { struct ip6_hdr *ip6; struct mld_hdr *mldh; struct ifnet *ifp; struct in6_multi *in6m = NULL; struct in6_addr mld_addr, all_in6; u_long timer = 0; /* timer value in the MLD query header */ struct psref psref; ifp = m_get_rcvif_psref(m, &psref); if (__predict_false(ifp == NULL)) goto out; IP6_EXTHDR_GET(mldh, struct mld_hdr *, m, off, sizeof(*mldh)); if (mldh == NULL) { ICMP6_STATINC(ICMP6_STAT_TOOSHORT); goto out_nodrop; } /* source address validation */ ip6 = mtod(m, struct ip6_hdr *);/* in case mpullup */ if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) { /* * RFC3590 allows the IPv6 unspecified address as the source * address of MLD report and done messages. However, as this * same document says, this special rule is for snooping * switches and the RFC requires routers to discard MLD packets * with the unspecified source address. The RFC only talks * about hosts receiving an MLD query or report in Security * Considerations, but this is probably the correct intention. * RFC3590 does not talk about other cases than link-local and * the unspecified source addresses, but we believe the same * rule should be applied. * As a result, we only allow link-local addresses as the * source address; otherwise, simply discard the packet. */ #if 0 /* * XXX: do not log in an input path to avoid log flooding, * though RFC3590 says "SHOULD log" if the source of a query * is the unspecified address. */ char ip6bufs[INET6_ADDRSTRLEN]; char ip6bufm[INET6_ADDRSTRLEN]; log(LOG_INFO, "mld_input: src %s is not link-local (grp=%s)\n", IN6_PRINT(ip6bufs,&ip6->ip6_src), IN6_PRINT(ip6bufm, &mldh->mld_addr)); #endif goto out; } /* * 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! */ goto out; } /* * In the MLD 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: { struct in6_multi *next; 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); rw_enter(&in6_multilock, RW_WRITER); /* * mld_stoptimer and mld_sendpkt release in6_multilock * temporarily, so we have to prevent in6m from being freed * while releasing the lock by having an extra reference to it. * * Also in6_purge_multi might remove items from the list of the * ifp while releasing the lock. Fortunately in6_purge_multi is * never executed as long as we have a psref of the ifp. */ LIST_FOREACH_SAFE(in6m, &ifp->if_multiaddrs, in6m_entry, next) { if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &all_in6) || IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) continue; if (in6m->in6m_state == MLD_REPORTPENDING) continue; /* we are not yet ready */ if (!IN6_IS_ADDR_UNSPECIFIED(&mld_addr) && !IN6_ARE_ADDR_EQUAL(&mld_addr, &in6m->in6m_addr)) continue; if (timer == 0) { in6m_ref(in6m); /* send a report immediately */ mld_stoptimer(in6m); mld_sendpkt(in6m, MLD_LISTENER_REPORT, NULL); in6m->in6m_state = MLD_IREPORTEDLAST; in6m_unref(in6m); /* May free in6m */ } else if (in6m->in6m_timer == IN6M_TIMER_UNDEF || mld_timerresid(in6m) > timer) { in6m->in6m_timer = 1 + (cprng_fast32() % timer) * hz / 1000; mld_starttimer(in6m); } } rw_exit(&in6_multilock); 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(&mldh->mld_addr)) break; /* * If we belong to the group being reported, stop * our timer for that group. */ rw_enter(&in6_multilock, RW_WRITER); in6m = in6_lookup_multi(&mld_addr, ifp); if (in6m) { in6m_ref(in6m); mld_stoptimer(in6m); /* transit to idle state */ in6m->in6m_state = MLD_OTHERLISTENER; /* clear flag */ in6m_unref(in6m); in6m = NULL; /* in6m might be freed */ } rw_exit(&in6_multilock); break; default: /* this is impossible */ #if 0 /* * this case should be impossible because of filtering in * icmp6_input(). But we explicitly disabled this part * just in case. */ log(LOG_ERR, "mld_input: illegal type(%d)", mldh->mld_type); #endif break; } out: m_freem(m); out_nodrop: m_put_rcvif_psref(ifp, &psref); } /* * XXX mld_sendpkt must be called with in6_multilock held and * will release in6_multilock before calling ip6_output and * returning to avoid locking against myself in ip6_output. */ static void mld_sendpkt(struct in6_multi *in6m, int type, const struct in6_addr *dst) { struct mbuf *mh; struct mld_hdr *mldh; struct ip6_hdr *ip6 = NULL; struct ip6_moptions im6o; struct in6_ifaddr *ia = NULL; struct ifnet *ifp = in6m->in6m_ifp; int ignflags; struct psref psref; int bound; KASSERT(rw_write_held(&in6_multilock)); /* * At first, find a link local address on the outgoing interface * to use as the source address of the MLD packet. * We do not reject tentative addresses for MLD report to deal with * the case where we first join a link-local address. */ ignflags = (IN6_IFF_NOTREADY|IN6_IFF_ANYCAST) & ~IN6_IFF_TENTATIVE; bound = curlwp_bind(); ia = in6ifa_ifpforlinklocal_psref(ifp, ignflags, &psref); if (ia == NULL) { curlwp_bindx(bound); return; } if ((ia->ia6_flags & IN6_IFF_TENTATIVE)) { ia6_release(ia, &psref); ia = NULL; } /* Allocate two mbufs to store IPv6 header and MLD header */ mldh = mld_allocbuf(&mh, sizeof(struct mld_hdr), in6m, type); if (mldh == NULL) { ia6_release(ia, &psref); curlwp_bindx(bound); return; } /* fill src/dst here */ ip6 = mtod(mh, struct ip6_hdr *); ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any; ip6->ip6_dst = dst ? *dst : in6m->in6m_addr; ia6_release(ia, &psref); curlwp_bindx(bound); 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 */ memset(&im6o, 0, sizeof(im6o)); im6o.im6o_multicast_if_index = if_get_index(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 */ ICMP6_STATINC(ICMP6_STAT_OUTHIST + type); icmp6_ifstat_inc(ifp, ifs6_out_msg); switch (type) { case MLD_LISTENER_QUERY: icmp6_ifstat_inc(ifp, ifs6_out_mldquery); break; case MLD_LISTENER_REPORT: icmp6_ifstat_inc(ifp, ifs6_out_mldreport); break; case MLD_LISTENER_DONE: icmp6_ifstat_inc(ifp, ifs6_out_mlddone); break; } /* XXX we cannot call ip6_output with holding in6_multilock */ rw_exit(&in6_multilock); ip6_output(mh, &ip6_opts, NULL, ia ? 0 : IPV6_UNSPECSRC, &im6o, NULL, NULL); rw_enter(&in6_multilock, RW_WRITER); } static struct mld_hdr * mld_allocbuf(struct mbuf **mh, int len, struct in6_multi *in6m, int type) { struct mbuf *md; struct mld_hdr *mldh; struct ip6_hdr *ip6; /* * 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 NULL; MGET(md, M_DONTWAIT, MT_DATA); if (md == NULL) { m_free(*mh); *mh = NULL; return NULL; } (*mh)->m_next = md; md->m_next = NULL; m_reset_rcvif((*mh)); (*mh)->m_pkthdr.len = sizeof(struct ip6_hdr) + len; (*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 *); memset(ip6, 0, sizeof(*ip6)); 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_src/dst will be set by mld_sendpkt() or mld_sendbuf() */ /* fill in the MLD header as much as possible */ md->m_len = len; mldh = mtod(md, struct mld_hdr *); memset(mldh, 0, len); mldh->mld_type = type; return mldh; } static void in6m_ref(struct in6_multi *in6m) { KASSERT(rw_write_held(&in6_multilock)); in6m->in6m_refcount++; } static void in6m_unref(struct in6_multi *in6m) { KASSERT(rw_write_held(&in6_multilock)); if (--in6m->in6m_refcount == 0) in6m_destroy(in6m); } /* * Add an address to the list of IP6 multicast addresses for a given interface. */ struct in6_multi * in6_addmulti(struct in6_addr *maddr6, struct ifnet *ifp, int *errorp, int timer) { struct sockaddr_in6 sin6; struct in6_multi *in6m; *errorp = 0; rw_enter(&in6_multilock, RW_WRITER); /* * See if address already in list. */ in6m = in6_lookup_multi(maddr6, ifp); if (in6m != NULL) { /* * Found it; just increment the refrence count. */ in6m->in6m_refcount++; } else { /* * New address; allocate a new multicast record * and link it into the interface's multicast list. */ in6m = (struct in6_multi *) malloc(sizeof(*in6m), M_IPMADDR, M_NOWAIT|M_ZERO); if (in6m == NULL) { *errorp = ENOBUFS; goto out; } in6m->in6m_addr = *maddr6; in6m->in6m_ifp = ifp; in6m->in6m_refcount = 1; in6m->in6m_timer = IN6M_TIMER_UNDEF; callout_init(&in6m->in6m_timer_ch, CALLOUT_MPSAFE); callout_setfunc(&in6m->in6m_timer_ch, mld_timeo, in6m); LIST_INSERT_HEAD(&ifp->if_multiaddrs, in6m, in6m_entry); /* * Ask the network driver to update its multicast reception * filter appropriately for the new address. */ sockaddr_in6_init(&sin6, maddr6, 0, 0, 0); *errorp = if_mcast_op(ifp, SIOCADDMULTI, sin6tosa(&sin6)); if (*errorp) { callout_destroy(&in6m->in6m_timer_ch); LIST_REMOVE(in6m, in6m_entry); free(in6m, M_IPMADDR); in6m = NULL; goto out; } in6m->in6m_timer = timer; if (in6m->in6m_timer > 0) { in6m->in6m_state = MLD_REPORTPENDING; mld_starttimer(in6m); goto out; } /* * Let MLD6 know that we have joined a new IP6 multicast * group. */ mld_start_listening(in6m); } out: rw_exit(&in6_multilock); return in6m; } static void in6m_destroy(struct in6_multi *in6m) { struct sockaddr_in6 sin6; KASSERT(rw_write_held(&in6_multilock)); KASSERT(in6m->in6m_refcount == 0); /* * Unlink from list if it's listed. This must be done before * mld_stop_listening because it releases in6_multilock and that allows * someone to look up the removing in6m from the list and add a * reference to the entry unexpectedly. */ if (in6_lookup_multi(&in6m->in6m_addr, in6m->in6m_ifp) != NULL) LIST_REMOVE(in6m, in6m_entry); /* * No remaining claims to this record; let MLD6 know * that we are leaving the multicast group. */ mld_stop_listening(in6m); /* * Delete all references of this multicasting group from * the membership arrays */ in6_purge_mcast_references(in6m); /* * Notify the network driver to update its multicast * reception filter. */ sockaddr_in6_init(&sin6, &in6m->in6m_addr, 0, 0, 0); if_mcast_op(in6m->in6m_ifp, SIOCDELMULTI, sin6tosa(&sin6)); /* Tell mld_timeo we're halting the timer */ in6m->in6m_timer = IN6M_TIMER_UNDEF; rw_exit(&in6_multilock); callout_halt(&in6m->in6m_timer_ch, NULL); callout_destroy(&in6m->in6m_timer_ch); free(in6m, M_IPMADDR); rw_enter(&in6_multilock, RW_WRITER); } /* * Delete a multicast address record. */ void in6_delmulti_locked(struct in6_multi *in6m) { KASSERT(rw_write_held(&in6_multilock)); KASSERT(in6m->in6m_refcount > 0); /* * The caller should have a reference to in6m. So we don't need to care * of releasing the lock in mld_stoptimer. */ mld_stoptimer(in6m); if (--in6m->in6m_refcount == 0) in6m_destroy(in6m); } void in6_delmulti(struct in6_multi *in6m) { rw_enter(&in6_multilock, RW_WRITER); in6_delmulti_locked(in6m); rw_exit(&in6_multilock); } /* * Look up the in6_multi record for a given IP6 multicast address * on a given interface. If no matching record is found, "in6m" * returns NULL. */ struct in6_multi * in6_lookup_multi(const struct in6_addr *addr, const struct ifnet *ifp) { struct in6_multi *in6m; KASSERT(rw_lock_held(&in6_multilock)); LIST_FOREACH(in6m, &ifp->if_multiaddrs, in6m_entry) { if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, addr)) break; } return in6m; } void in6_lookup_and_delete_multi(const struct in6_addr *addr, const struct ifnet *ifp) { struct in6_multi *in6m; rw_enter(&in6_multilock, RW_WRITER); in6m = in6_lookup_multi(addr, ifp); if (in6m != NULL) in6_delmulti_locked(in6m); rw_exit(&in6_multilock); } bool in6_multi_group(const struct in6_addr *addr, const struct ifnet *ifp) { bool ingroup; rw_enter(&in6_multilock, RW_READER); ingroup = in6_lookup_multi(addr, ifp) != NULL; rw_exit(&in6_multilock); return ingroup; } /* * Purge in6_multi records associated to the interface. */ void in6_purge_multi(struct ifnet *ifp) { struct in6_multi *in6m, *next; rw_enter(&in6_multilock, RW_WRITER); LIST_FOREACH_SAFE(in6m, &ifp->if_multiaddrs, in6m_entry, next) { LIST_REMOVE(in6m, in6m_entry); /* * Normally multicast addresses are already purged at this * point. Remaining references aren't accessible via ifp, * so what we can do here is to prevent ifp from being * accessed via in6m by removing it from the list of ifp. */ mld_stoptimer(in6m); } rw_exit(&in6_multilock); } void in6_multi_lock(int op) { rw_enter(&in6_multilock, op); } void in6_multi_unlock(void) { rw_exit(&in6_multilock); } bool in6_multi_locked(int op) { switch (op) { case RW_READER: return rw_read_held(&in6_multilock); case RW_WRITER: return rw_write_held(&in6_multilock); default: return rw_lock_held(&in6_multilock); } } struct in6_multi_mship * in6_joingroup(struct ifnet *ifp, struct in6_addr *addr, int *errorp, int timer) { struct in6_multi_mship *imm; imm = malloc(sizeof(*imm), M_IPMADDR, M_NOWAIT|M_ZERO); if (imm == NULL) { *errorp = ENOBUFS; return NULL; } imm->i6mm_maddr = in6_addmulti(addr, ifp, errorp, timer); if (!imm->i6mm_maddr) { /* *errorp is already set */ free(imm, M_IPMADDR); return NULL; } return imm; } int in6_leavegroup(struct in6_multi_mship *imm) { struct in6_multi *in6m; rw_enter(&in6_multilock, RW_WRITER); in6m = imm->i6mm_maddr; imm->i6mm_maddr = NULL; if (in6m != NULL) { in6_delmulti_locked(in6m); } rw_exit(&in6_multilock); free(imm, M_IPMADDR); return 0; } /* * DEPRECATED: keep it just to avoid breaking old sysctl users. */ static int in6_mkludge_sysctl(SYSCTLFN_ARGS) { if (namelen != 1) return EINVAL; *oldlenp = 0; return 0; } static int in6_multicast_sysctl(SYSCTLFN_ARGS) { struct ifnet *ifp; struct ifaddr *ifa; struct in6_ifaddr *ia6; struct in6_multi *in6m; uint32_t tmp; int error; size_t written; struct psref psref, psref_ia; int bound, s; if (namelen != 1) return EINVAL; rw_enter(&in6_multilock, RW_READER); bound = curlwp_bind(); ifp = if_get_byindex(name[0], &psref); if (ifp == NULL) { curlwp_bindx(bound); rw_exit(&in6_multilock); return ENODEV; } if (oldp == NULL) { *oldlenp = 0; s = pserialize_read_enter(); IFADDR_READER_FOREACH(ifa, ifp) { LIST_FOREACH(in6m, &ifp->if_multiaddrs, in6m_entry) { *oldlenp += 2 * sizeof(struct in6_addr) + sizeof(uint32_t); } } pserialize_read_exit(s); if_put(ifp, &psref); curlwp_bindx(bound); rw_exit(&in6_multilock); return 0; } error = 0; written = 0; s = pserialize_read_enter(); IFADDR_READER_FOREACH(ifa, ifp) { if (ifa->ifa_addr->sa_family != AF_INET6) continue; ifa_acquire(ifa, &psref_ia); pserialize_read_exit(s); ia6 = ifatoia6(ifa); LIST_FOREACH(in6m, &ifp->if_multiaddrs, in6m_entry) { if (written + 2 * sizeof(struct in6_addr) + sizeof(uint32_t) > *oldlenp) goto done; /* * XXX return the first IPv6 address to keep backward * compatibility, however now multicast addresses * don't belong to any IPv6 addresses so it should be * unnecessary. */ error = sysctl_copyout(l, &ia6->ia_addr.sin6_addr, oldp, sizeof(struct in6_addr)); if (error) goto done; oldp = (char *)oldp + sizeof(struct in6_addr); written += sizeof(struct in6_addr); error = sysctl_copyout(l, &in6m->in6m_addr, oldp, sizeof(struct in6_addr)); if (error) goto done; oldp = (char *)oldp + sizeof(struct in6_addr); written += sizeof(struct in6_addr); tmp = in6m->in6m_refcount; error = sysctl_copyout(l, &tmp, oldp, sizeof(tmp)); if (error) goto done; oldp = (char *)oldp + sizeof(tmp); written += sizeof(tmp); } s = pserialize_read_enter(); break; } pserialize_read_exit(s); done: ifa_release(ifa, &psref_ia); if_put(ifp, &psref); curlwp_bindx(bound); rw_exit(&in6_multilock); *oldlenp = written; return error; } void in6_sysctl_multicast_setup(struct sysctllog **clog) { sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT, CTLTYPE_NODE, "inet6", NULL, NULL, 0, NULL, 0, CTL_NET, PF_INET6, CTL_EOL); sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT, CTLTYPE_NODE, "multicast", SYSCTL_DESCR("Multicast information"), in6_multicast_sysctl, 0, NULL, 0, CTL_NET, PF_INET6, CTL_CREATE, CTL_EOL); sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT, CTLTYPE_NODE, "multicast_kludge", SYSCTL_DESCR("multicast kludge information"), in6_mkludge_sysctl, 0, NULL, 0, CTL_NET, PF_INET6, CTL_CREATE, CTL_EOL); }