The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/netinet/igmp.c

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    1 /*-
    2  * Copyright (c) 2007-2009 Bruce Simpson.
    3  * Copyright (c) 1988 Stephen Deering.
    4  * Copyright (c) 1992, 1993
    5  *      The Regents of the University of California.  All rights reserved.
    6  *
    7  * This code is derived from software contributed to Berkeley by
    8  * Stephen Deering of Stanford University.
    9  *
   10  * Redistribution and use in source and binary forms, with or without
   11  * modification, are permitted provided that the following conditions
   12  * are met:
   13  * 1. Redistributions of source code must retain the above copyright
   14  *    notice, this list of conditions and the following disclaimer.
   15  * 2. Redistributions in binary form must reproduce the above copyright
   16  *    notice, this list of conditions and the following disclaimer in the
   17  *    documentation and/or other materials provided with the distribution.
   18  * 4. Neither the name of the University nor the names of its contributors
   19  *    may be used to endorse or promote products derived from this software
   20  *    without specific prior written permission.
   21  *
   22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   32  * SUCH DAMAGE.
   33  *
   34  *      @(#)igmp.c      8.1 (Berkeley) 7/19/93
   35  */
   36 
   37 /*
   38  * Internet Group Management Protocol (IGMP) routines.
   39  * [RFC1112, RFC2236, RFC3376]
   40  *
   41  * Written by Steve Deering, Stanford, May 1988.
   42  * Modified by Rosen Sharma, Stanford, Aug 1994.
   43  * Modified by Bill Fenner, Xerox PARC, Feb 1995.
   44  * Modified to fully comply to IGMPv2 by Bill Fenner, Oct 1995.
   45  * Significantly rewritten for IGMPv3, VIMAGE, and SMP by Bruce Simpson.
   46  *
   47  * MULTICAST Revision: 3.5.1.4
   48  */
   49 
   50 #include <sys/cdefs.h>
   51 __FBSDID("$FreeBSD: releng/8.4/sys/netinet/igmp.c 281233 2015-04-07 20:21:23Z delphij $");
   52 
   53 #include <sys/param.h>
   54 #include <sys/systm.h>
   55 #include <sys/module.h>
   56 #include <sys/malloc.h>
   57 #include <sys/mbuf.h>
   58 #include <sys/socket.h>
   59 #include <sys/protosw.h>
   60 #include <sys/kernel.h>
   61 #include <sys/sysctl.h>
   62 #include <sys/ktr.h>
   63 #include <sys/condvar.h>
   64 
   65 #include <net/if.h>
   66 #include <net/netisr.h>
   67 #include <net/vnet.h>
   68 
   69 #include <netinet/in.h>
   70 #include <netinet/in_var.h>
   71 #include <netinet/in_systm.h>
   72 #include <netinet/ip.h>
   73 #include <netinet/ip_var.h>
   74 #include <netinet/ip_options.h>
   75 #include <netinet/igmp.h>
   76 #include <netinet/igmp_var.h>
   77 
   78 #include <machine/in_cksum.h>
   79 
   80 #include <security/mac/mac_framework.h>
   81 
   82 #ifndef KTR_IGMPV3
   83 #define KTR_IGMPV3 KTR_INET
   84 #endif
   85 
   86 static struct igmp_ifinfo *
   87                 igi_alloc_locked(struct ifnet *);
   88 static void     igi_delete_locked(const struct ifnet *);
   89 static void     igmp_dispatch_queue(struct ifqueue *, int, const int);
   90 static void     igmp_fasttimo_vnet(void);
   91 static void     igmp_final_leave(struct in_multi *, struct igmp_ifinfo *);
   92 static int      igmp_handle_state_change(struct in_multi *,
   93                     struct igmp_ifinfo *);
   94 static int      igmp_initial_join(struct in_multi *, struct igmp_ifinfo *);
   95 static int      igmp_input_v1_query(struct ifnet *, const struct ip *,
   96                     const struct igmp *);
   97 static int      igmp_input_v2_query(struct ifnet *, const struct ip *,
   98                     const struct igmp *);
   99 static int      igmp_input_v3_query(struct ifnet *, const struct ip *,
  100                     /*const*/ struct igmpv3 *);
  101 static int      igmp_input_v3_group_query(struct in_multi *,
  102                     struct igmp_ifinfo *, int, /*const*/ struct igmpv3 *);
  103 static int      igmp_input_v1_report(struct ifnet *, /*const*/ struct ip *,
  104                     /*const*/ struct igmp *);
  105 static int      igmp_input_v2_report(struct ifnet *, /*const*/ struct ip *,
  106                     /*const*/ struct igmp *);
  107 static void     igmp_intr(struct mbuf *);
  108 static int      igmp_isgroupreported(const struct in_addr);
  109 static struct mbuf *
  110                 igmp_ra_alloc(void);
  111 #ifdef KTR
  112 static char *   igmp_rec_type_to_str(const int);
  113 #endif
  114 static void     igmp_set_version(struct igmp_ifinfo *, const int);
  115 static void     igmp_slowtimo_vnet(void);
  116 static int      igmp_v1v2_queue_report(struct in_multi *, const int);
  117 static void     igmp_v1v2_process_group_timer(struct in_multi *, const int);
  118 static void     igmp_v1v2_process_querier_timers(struct igmp_ifinfo *);
  119 static void     igmp_v2_update_group(struct in_multi *, const int);
  120 static void     igmp_v3_cancel_link_timers(struct igmp_ifinfo *);
  121 static void     igmp_v3_dispatch_general_query(struct igmp_ifinfo *);
  122 static struct mbuf *
  123                 igmp_v3_encap_report(struct ifnet *, struct mbuf *);
  124 static int      igmp_v3_enqueue_group_record(struct ifqueue *,
  125                     struct in_multi *, const int, const int, const int);
  126 static int      igmp_v3_enqueue_filter_change(struct ifqueue *,
  127                     struct in_multi *);
  128 static void     igmp_v3_process_group_timers(struct igmp_ifinfo *,
  129                     struct ifqueue *, struct ifqueue *, struct in_multi *,
  130                     const int);
  131 static int      igmp_v3_merge_state_changes(struct in_multi *,
  132                     struct ifqueue *);
  133 static void     igmp_v3_suppress_group_record(struct in_multi *);
  134 static int      sysctl_igmp_default_version(SYSCTL_HANDLER_ARGS);
  135 static int      sysctl_igmp_gsr(SYSCTL_HANDLER_ARGS);
  136 static int      sysctl_igmp_ifinfo(SYSCTL_HANDLER_ARGS);
  137 
  138 static const struct netisr_handler igmp_nh = {
  139         .nh_name = "igmp",
  140         .nh_handler = igmp_intr,
  141         .nh_proto = NETISR_IGMP,
  142         .nh_policy = NETISR_POLICY_SOURCE,
  143 };
  144 
  145 /*
  146  * System-wide globals.
  147  *
  148  * Unlocked access to these is OK, except for the global IGMP output
  149  * queue. The IGMP subsystem lock ends up being system-wide for the moment,
  150  * because all VIMAGEs have to share a global output queue, as netisrs
  151  * themselves are not virtualized.
  152  *
  153  * Locking:
  154  *  * The permitted lock order is: IN_MULTI_LOCK, IGMP_LOCK, IF_ADDR_LOCK.
  155  *    Any may be taken independently; if any are held at the same
  156  *    time, the above lock order must be followed.
  157  *  * All output is delegated to the netisr.
  158  *    Now that Giant has been eliminated, the netisr may be inlined.
  159  *  * IN_MULTI_LOCK covers in_multi.
  160  *  * IGMP_LOCK covers igmp_ifinfo and any global variables in this file,
  161  *    including the output queue.
  162  *  * IF_ADDR_LOCK covers if_multiaddrs, which is used for a variety of
  163  *    per-link state iterators.
  164  *  * igmp_ifinfo is valid as long as PF_INET is attached to the interface,
  165  *    therefore it is not refcounted.
  166  *    We allow unlocked reads of igmp_ifinfo when accessed via in_multi.
  167  *
  168  * Reference counting
  169  *  * IGMP acquires its own reference every time an in_multi is passed to
  170  *    it and the group is being joined for the first time.
  171  *  * IGMP releases its reference(s) on in_multi in a deferred way,
  172  *    because the operations which process the release run as part of
  173  *    a loop whose control variables are directly affected by the release
  174  *    (that, and not recursing on the IF_ADDR_LOCK).
  175  *
  176  * VIMAGE: Each in_multi corresponds to an ifp, and each ifp corresponds
  177  * to a vnet in ifp->if_vnet.
  178  *
  179  * SMPng: XXX We may potentially race operations on ifma_protospec.
  180  * The problem is that we currently lack a clean way of taking the
  181  * IF_ADDR_LOCK() between the ifnet and in layers w/o recursing,
  182  * as anything which modifies ifma needs to be covered by that lock.
  183  * So check for ifma_protospec being NULL before proceeding.
  184  */
  185 struct mtx               igmp_mtx;
  186 
  187 struct mbuf             *m_raopt;                /* Router Alert option */
  188 MALLOC_DEFINE(M_IGMP, "igmp", "igmp state");
  189 
  190 /*
  191  * VIMAGE-wide globals.
  192  *
  193  * The IGMPv3 timers themselves need to run per-image, however,
  194  * protosw timers run globally (see tcp).
  195  * An ifnet can only be in one vimage at a time, and the loopback
  196  * ifnet, loif, is itself virtualized.
  197  * It would otherwise be possible to seriously hose IGMP state,
  198  * and create inconsistencies in upstream multicast routing, if you have
  199  * multiple VIMAGEs running on the same link joining different multicast
  200  * groups, UNLESS the "primary IP address" is different. This is because
  201  * IGMP for IPv4 does not force link-local addresses to be used for each
  202  * node, unlike MLD for IPv6.
  203  * Obviously the IGMPv3 per-interface state has per-vimage granularity
  204  * also as a result.
  205  *
  206  * FUTURE: Stop using IFP_TO_IA/INADDR_ANY, and use source address selection
  207  * policy to control the address used by IGMP on the link.
  208  */
  209 static VNET_DEFINE(int, interface_timers_running);      /* IGMPv3 general
  210                                                          * query response */
  211 static VNET_DEFINE(int, state_change_timers_running);   /* IGMPv3 state-change
  212                                                          * retransmit */
  213 static VNET_DEFINE(int, current_state_timers_running);  /* IGMPv1/v2 host
  214                                                          * report; IGMPv3 g/sg
  215                                                          * query response */
  216 
  217 #define V_interface_timers_running      VNET(interface_timers_running)
  218 #define V_state_change_timers_running   VNET(state_change_timers_running)
  219 #define V_current_state_timers_running  VNET(current_state_timers_running)
  220 
  221 static VNET_DEFINE(LIST_HEAD(, igmp_ifinfo), igi_head);
  222 static VNET_DEFINE(struct igmpstat, igmpstat) = {
  223         .igps_version = IGPS_VERSION_3,
  224         .igps_len = sizeof(struct igmpstat),
  225 };
  226 static VNET_DEFINE(struct timeval, igmp_gsrdelay) = {10, 0};
  227 
  228 #define V_igi_head                      VNET(igi_head)
  229 #define V_igmpstat                      VNET(igmpstat)
  230 #define V_igmp_gsrdelay                 VNET(igmp_gsrdelay)
  231 
  232 static VNET_DEFINE(int, igmp_recvifkludge) = 1;
  233 static VNET_DEFINE(int, igmp_sendra) = 1;
  234 static VNET_DEFINE(int, igmp_sendlocal) = 1;
  235 static VNET_DEFINE(int, igmp_v1enable) = 1;
  236 static VNET_DEFINE(int, igmp_v2enable) = 1;
  237 static VNET_DEFINE(int, igmp_legacysupp);
  238 static VNET_DEFINE(int, igmp_default_version) = IGMP_VERSION_3;
  239 
  240 #define V_igmp_recvifkludge             VNET(igmp_recvifkludge)
  241 #define V_igmp_sendra                   VNET(igmp_sendra)
  242 #define V_igmp_sendlocal                VNET(igmp_sendlocal)
  243 #define V_igmp_v1enable                 VNET(igmp_v1enable)
  244 #define V_igmp_v2enable                 VNET(igmp_v2enable)
  245 #define V_igmp_legacysupp               VNET(igmp_legacysupp)
  246 #define V_igmp_default_version          VNET(igmp_default_version)
  247 
  248 /*
  249  * Virtualized sysctls.
  250  */
  251 SYSCTL_VNET_STRUCT(_net_inet_igmp, IGMPCTL_STATS, stats, CTLFLAG_RW,
  252     &VNET_NAME(igmpstat), igmpstat, "");
  253 SYSCTL_VNET_INT(_net_inet_igmp, OID_AUTO, recvifkludge, CTLFLAG_RW,
  254     &VNET_NAME(igmp_recvifkludge), 0,
  255     "Rewrite IGMPv1/v2 reports from 0.0.0.0 to contain subnet address");
  256 SYSCTL_VNET_INT(_net_inet_igmp, OID_AUTO, sendra, CTLFLAG_RW,
  257     &VNET_NAME(igmp_sendra), 0,
  258     "Send IP Router Alert option in IGMPv2/v3 messages");
  259 SYSCTL_VNET_INT(_net_inet_igmp, OID_AUTO, sendlocal, CTLFLAG_RW,
  260     &VNET_NAME(igmp_sendlocal), 0,
  261     "Send IGMP membership reports for 224.0.0.0/24 groups");
  262 SYSCTL_VNET_INT(_net_inet_igmp, OID_AUTO, v1enable, CTLFLAG_RW,
  263     &VNET_NAME(igmp_v1enable), 0,
  264     "Enable backwards compatibility with IGMPv1");
  265 SYSCTL_VNET_INT(_net_inet_igmp, OID_AUTO, v2enable, CTLFLAG_RW,
  266     &VNET_NAME(igmp_v2enable), 0,
  267     "Enable backwards compatibility with IGMPv2");
  268 SYSCTL_VNET_INT(_net_inet_igmp, OID_AUTO, legacysupp, CTLFLAG_RW,
  269     &VNET_NAME(igmp_legacysupp), 0,
  270     "Allow v1/v2 reports to suppress v3 group responses");
  271 SYSCTL_VNET_PROC(_net_inet_igmp, OID_AUTO, default_version,
  272     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
  273     &VNET_NAME(igmp_default_version), 0, sysctl_igmp_default_version, "I",
  274     "Default version of IGMP to run on each interface");
  275 SYSCTL_VNET_PROC(_net_inet_igmp, OID_AUTO, gsrdelay,
  276     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
  277     &VNET_NAME(igmp_gsrdelay.tv_sec), 0, sysctl_igmp_gsr, "I",
  278     "Rate limit for IGMPv3 Group-and-Source queries in seconds");
  279 
  280 /*
  281  * Non-virtualized sysctls.
  282  */
  283 SYSCTL_NODE(_net_inet_igmp, OID_AUTO, ifinfo, CTLFLAG_RD | CTLFLAG_MPSAFE,
  284     sysctl_igmp_ifinfo, "Per-interface IGMPv3 state");
  285 
  286 static __inline void
  287 igmp_save_context(struct mbuf *m, struct ifnet *ifp)
  288 {
  289 
  290 #ifdef VIMAGE
  291         m->m_pkthdr.header = ifp->if_vnet;
  292 #endif /* VIMAGE */
  293         m->m_pkthdr.flowid = ifp->if_index;
  294 }
  295 
  296 static __inline void
  297 igmp_scrub_context(struct mbuf *m)
  298 {
  299 
  300         m->m_pkthdr.header = NULL;
  301         m->m_pkthdr.flowid = 0;
  302 }
  303 
  304 #ifdef KTR
  305 static __inline char *
  306 inet_ntoa_haddr(in_addr_t haddr)
  307 {
  308         struct in_addr ia;
  309 
  310         ia.s_addr = htonl(haddr);
  311         return (inet_ntoa(ia));
  312 }
  313 #endif
  314 
  315 /*
  316  * Restore context from a queued IGMP output chain.
  317  * Return saved ifindex.
  318  *
  319  * VIMAGE: The assertion is there to make sure that we
  320  * actually called CURVNET_SET() with what's in the mbuf chain.
  321  */
  322 static __inline uint32_t
  323 igmp_restore_context(struct mbuf *m)
  324 {
  325 
  326 #ifdef notyet
  327 #if defined(VIMAGE) && defined(INVARIANTS)
  328         KASSERT(curvnet == (m->m_pkthdr.header),
  329             ("%s: called when curvnet was not restored", __func__));
  330 #endif
  331 #endif
  332         return (m->m_pkthdr.flowid);
  333 }
  334 
  335 /*
  336  * Retrieve or set default IGMP version.
  337  *
  338  * VIMAGE: Assume curvnet set by caller.
  339  * SMPng: NOTE: Serialized by IGMP lock.
  340  */
  341 static int
  342 sysctl_igmp_default_version(SYSCTL_HANDLER_ARGS)
  343 {
  344         int      error;
  345         int      new;
  346 
  347         error = sysctl_wire_old_buffer(req, sizeof(int));
  348         if (error)
  349                 return (error);
  350 
  351         IGMP_LOCK();
  352 
  353         new = V_igmp_default_version;
  354 
  355         error = sysctl_handle_int(oidp, &new, 0, req);
  356         if (error || !req->newptr)
  357                 goto out_locked;
  358 
  359         if (new < IGMP_VERSION_1 || new > IGMP_VERSION_3) {
  360                 error = EINVAL;
  361                 goto out_locked;
  362         }
  363 
  364         CTR2(KTR_IGMPV3, "change igmp_default_version from %d to %d",
  365              V_igmp_default_version, new);
  366 
  367         V_igmp_default_version = new;
  368 
  369 out_locked:
  370         IGMP_UNLOCK();
  371         return (error);
  372 }
  373 
  374 /*
  375  * Retrieve or set threshold between group-source queries in seconds.
  376  *
  377  * VIMAGE: Assume curvnet set by caller.
  378  * SMPng: NOTE: Serialized by IGMP lock.
  379  */
  380 static int
  381 sysctl_igmp_gsr(SYSCTL_HANDLER_ARGS)
  382 {
  383         int error;
  384         int i;
  385 
  386         error = sysctl_wire_old_buffer(req, sizeof(int));
  387         if (error)
  388                 return (error);
  389 
  390         IGMP_LOCK();
  391 
  392         i = V_igmp_gsrdelay.tv_sec;
  393 
  394         error = sysctl_handle_int(oidp, &i, 0, req);
  395         if (error || !req->newptr)
  396                 goto out_locked;
  397 
  398         if (i < -1 || i >= 60) {
  399                 error = EINVAL;
  400                 goto out_locked;
  401         }
  402 
  403         CTR2(KTR_IGMPV3, "change igmp_gsrdelay from %d to %d",
  404              V_igmp_gsrdelay.tv_sec, i);
  405         V_igmp_gsrdelay.tv_sec = i;
  406 
  407 out_locked:
  408         IGMP_UNLOCK();
  409         return (error);
  410 }
  411 
  412 /*
  413  * Expose struct igmp_ifinfo to userland, keyed by ifindex.
  414  * For use by ifmcstat(8).
  415  *
  416  * SMPng: NOTE: Does an unlocked ifindex space read.
  417  * VIMAGE: Assume curvnet set by caller. The node handler itself
  418  * is not directly virtualized.
  419  */
  420 static int
  421 sysctl_igmp_ifinfo(SYSCTL_HANDLER_ARGS)
  422 {
  423         int                     *name;
  424         int                      error;
  425         u_int                    namelen;
  426         struct ifnet            *ifp;
  427         struct igmp_ifinfo      *igi;
  428 
  429         name = (int *)arg1;
  430         namelen = arg2;
  431 
  432         if (req->newptr != NULL)
  433                 return (EPERM);
  434 
  435         if (namelen != 1)
  436                 return (EINVAL);
  437 
  438         error = sysctl_wire_old_buffer(req, sizeof(struct igmp_ifinfo));
  439         if (error)
  440                 return (error);
  441 
  442         IN_MULTI_LOCK();
  443         IGMP_LOCK();
  444 
  445         if (name[0] <= 0 || name[0] > V_if_index) {
  446                 error = ENOENT;
  447                 goto out_locked;
  448         }
  449 
  450         error = ENOENT;
  451 
  452         ifp = ifnet_byindex(name[0]);
  453         if (ifp == NULL)
  454                 goto out_locked;
  455 
  456         LIST_FOREACH(igi, &V_igi_head, igi_link) {
  457                 if (ifp == igi->igi_ifp) {
  458                         error = SYSCTL_OUT(req, igi,
  459                             sizeof(struct igmp_ifinfo));
  460                         break;
  461                 }
  462         }
  463 
  464 out_locked:
  465         IGMP_UNLOCK();
  466         IN_MULTI_UNLOCK();
  467         return (error);
  468 }
  469 
  470 /*
  471  * Dispatch an entire queue of pending packet chains
  472  * using the netisr.
  473  * VIMAGE: Assumes the vnet pointer has been set.
  474  */
  475 static void
  476 igmp_dispatch_queue(struct ifqueue *ifq, int limit, const int loop)
  477 {
  478         struct mbuf *m;
  479 
  480         for (;;) {
  481                 _IF_DEQUEUE(ifq, m);
  482                 if (m == NULL)
  483                         break;
  484                 CTR3(KTR_IGMPV3, "%s: dispatch %p from %p", __func__, ifq, m);
  485                 if (loop)
  486                         m->m_flags |= M_IGMP_LOOP;
  487                 netisr_dispatch(NETISR_IGMP, m);
  488                 if (--limit == 0)
  489                         break;
  490         }
  491 }
  492 
  493 /*
  494  * Filter outgoing IGMP report state by group.
  495  *
  496  * Reports are ALWAYS suppressed for ALL-HOSTS (224.0.0.1).
  497  * If the net.inet.igmp.sendlocal sysctl is 0, then IGMP reports are
  498  * disabled for all groups in the 224.0.0.0/24 link-local scope. However,
  499  * this may break certain IGMP snooping switches which rely on the old
  500  * report behaviour.
  501  *
  502  * Return zero if the given group is one for which IGMP reports
  503  * should be suppressed, or non-zero if reports should be issued.
  504  */
  505 static __inline int
  506 igmp_isgroupreported(const struct in_addr addr)
  507 {
  508 
  509         if (in_allhosts(addr) ||
  510             ((!V_igmp_sendlocal && IN_LOCAL_GROUP(ntohl(addr.s_addr)))))
  511                 return (0);
  512 
  513         return (1);
  514 }
  515 
  516 /*
  517  * Construct a Router Alert option to use in outgoing packets.
  518  */
  519 static struct mbuf *
  520 igmp_ra_alloc(void)
  521 {
  522         struct mbuf     *m;
  523         struct ipoption *p;
  524 
  525         MGET(m, M_DONTWAIT, MT_DATA);
  526         p = mtod(m, struct ipoption *);
  527         p->ipopt_dst.s_addr = INADDR_ANY;
  528         p->ipopt_list[0] = IPOPT_RA;    /* Router Alert Option */
  529         p->ipopt_list[1] = 0x04;        /* 4 bytes long */
  530         p->ipopt_list[2] = IPOPT_EOL;   /* End of IP option list */
  531         p->ipopt_list[3] = 0x00;        /* pad byte */
  532         m->m_len = sizeof(p->ipopt_dst) + p->ipopt_list[1];
  533 
  534         return (m);
  535 }
  536 
  537 /*
  538  * Attach IGMP when PF_INET is attached to an interface.
  539  */
  540 struct igmp_ifinfo *
  541 igmp_domifattach(struct ifnet *ifp)
  542 {
  543         struct igmp_ifinfo *igi;
  544 
  545         CTR3(KTR_IGMPV3, "%s: called for ifp %p(%s)",
  546             __func__, ifp, ifp->if_xname);
  547 
  548         IGMP_LOCK();
  549 
  550         igi = igi_alloc_locked(ifp);
  551         if (!(ifp->if_flags & IFF_MULTICAST))
  552                 igi->igi_flags |= IGIF_SILENT;
  553 
  554         IGMP_UNLOCK();
  555 
  556         return (igi);
  557 }
  558 
  559 /*
  560  * VIMAGE: assume curvnet set by caller.
  561  */
  562 static struct igmp_ifinfo *
  563 igi_alloc_locked(/*const*/ struct ifnet *ifp)
  564 {
  565         struct igmp_ifinfo *igi;
  566 
  567         IGMP_LOCK_ASSERT();
  568 
  569         igi = malloc(sizeof(struct igmp_ifinfo), M_IGMP, M_NOWAIT|M_ZERO);
  570         if (igi == NULL)
  571                 goto out;
  572 
  573         igi->igi_ifp = ifp;
  574         igi->igi_version = V_igmp_default_version;
  575         igi->igi_flags = 0;
  576         igi->igi_rv = IGMP_RV_INIT;
  577         igi->igi_qi = IGMP_QI_INIT;
  578         igi->igi_qri = IGMP_QRI_INIT;
  579         igi->igi_uri = IGMP_URI_INIT;
  580 
  581         SLIST_INIT(&igi->igi_relinmhead);
  582 
  583         /*
  584          * Responses to general queries are subject to bounds.
  585          */
  586         IFQ_SET_MAXLEN(&igi->igi_gq, IGMP_MAX_RESPONSE_PACKETS);
  587 
  588         LIST_INSERT_HEAD(&V_igi_head, igi, igi_link);
  589 
  590         CTR2(KTR_IGMPV3, "allocate igmp_ifinfo for ifp %p(%s)",
  591              ifp, ifp->if_xname);
  592 
  593 out:
  594         return (igi);
  595 }
  596 
  597 /*
  598  * Hook for ifdetach.
  599  *
  600  * NOTE: Some finalization tasks need to run before the protocol domain
  601  * is detached, but also before the link layer does its cleanup.
  602  *
  603  * SMPNG: igmp_ifdetach() needs to take IF_ADDR_LOCK().
  604  * XXX This is also bitten by unlocked ifma_protospec access.
  605  */
  606 void
  607 igmp_ifdetach(struct ifnet *ifp)
  608 {
  609         struct igmp_ifinfo      *igi;
  610         struct ifmultiaddr      *ifma;
  611         struct in_multi         *inm, *tinm;
  612 
  613         CTR3(KTR_IGMPV3, "%s: called for ifp %p(%s)", __func__, ifp,
  614             ifp->if_xname);
  615 
  616         IGMP_LOCK();
  617 
  618         igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
  619         if (igi->igi_version == IGMP_VERSION_3) {
  620                 IF_ADDR_RLOCK(ifp);
  621                 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
  622                         if (ifma->ifma_addr->sa_family != AF_INET ||
  623                             ifma->ifma_protospec == NULL)
  624                                 continue;
  625 #if 0
  626                         KASSERT(ifma->ifma_protospec != NULL,
  627                             ("%s: ifma_protospec is NULL", __func__));
  628 #endif
  629                         inm = (struct in_multi *)ifma->ifma_protospec;
  630                         if (inm->inm_state == IGMP_LEAVING_MEMBER) {
  631                                 SLIST_INSERT_HEAD(&igi->igi_relinmhead,
  632                                     inm, inm_nrele);
  633                         }
  634                         inm_clear_recorded(inm);
  635                 }
  636                 IF_ADDR_RUNLOCK(ifp);
  637                 /*
  638                  * Free the in_multi reference(s) for this IGMP lifecycle.
  639                  */
  640                 SLIST_FOREACH_SAFE(inm, &igi->igi_relinmhead, inm_nrele,
  641                     tinm) {
  642                         SLIST_REMOVE_HEAD(&igi->igi_relinmhead, inm_nrele);
  643                         inm_release_locked(inm);
  644                 }
  645         }
  646 
  647         IGMP_UNLOCK();
  648 }
  649 
  650 /*
  651  * Hook for domifdetach.
  652  */
  653 void
  654 igmp_domifdetach(struct ifnet *ifp)
  655 {
  656         struct igmp_ifinfo *igi;
  657 
  658         CTR3(KTR_IGMPV3, "%s: called for ifp %p(%s)",
  659             __func__, ifp, ifp->if_xname);
  660 
  661         IGMP_LOCK();
  662 
  663         igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
  664         igi_delete_locked(ifp);
  665 
  666         IGMP_UNLOCK();
  667 }
  668 
  669 static void
  670 igi_delete_locked(const struct ifnet *ifp)
  671 {
  672         struct igmp_ifinfo *igi, *tigi;
  673 
  674         CTR3(KTR_IGMPV3, "%s: freeing igmp_ifinfo for ifp %p(%s)",
  675             __func__, ifp, ifp->if_xname);
  676 
  677         IGMP_LOCK_ASSERT();
  678 
  679         LIST_FOREACH_SAFE(igi, &V_igi_head, igi_link, tigi) {
  680                 if (igi->igi_ifp == ifp) {
  681                         /*
  682                          * Free deferred General Query responses.
  683                          */
  684                         _IF_DRAIN(&igi->igi_gq);
  685 
  686                         LIST_REMOVE(igi, igi_link);
  687 
  688                         KASSERT(SLIST_EMPTY(&igi->igi_relinmhead),
  689                             ("%s: there are dangling in_multi references",
  690                             __func__));
  691 
  692                         free(igi, M_IGMP);
  693                         return;
  694                 }
  695         }
  696 
  697 #ifdef INVARIANTS
  698         panic("%s: igmp_ifinfo not found for ifp %p\n", __func__,  ifp);
  699 #endif
  700 }
  701 
  702 /*
  703  * Process a received IGMPv1 query.
  704  * Return non-zero if the message should be dropped.
  705  *
  706  * VIMAGE: The curvnet pointer is derived from the input ifp.
  707  */
  708 static int
  709 igmp_input_v1_query(struct ifnet *ifp, const struct ip *ip,
  710     const struct igmp *igmp)
  711 {
  712         struct ifmultiaddr      *ifma;
  713         struct igmp_ifinfo      *igi;
  714         struct in_multi         *inm;
  715 
  716         /*
  717          * IGMPv1 Host Mmembership Queries SHOULD always be addressed to
  718          * 224.0.0.1. They are always treated as General Queries.
  719          * igmp_group is always ignored. Do not drop it as a userland
  720          * daemon may wish to see it.
  721          * XXX SMPng: unlocked increments in igmpstat assumed atomic.
  722          */
  723         if (!in_allhosts(ip->ip_dst) || !in_nullhost(igmp->igmp_group)) {
  724                 IGMPSTAT_INC(igps_rcv_badqueries);
  725                 return (0);
  726         }
  727         IGMPSTAT_INC(igps_rcv_gen_queries);
  728 
  729         IN_MULTI_LOCK();
  730         IGMP_LOCK();
  731 
  732         igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
  733         KASSERT(igi != NULL, ("%s: no igmp_ifinfo for ifp %p", __func__, ifp));
  734 
  735         if (igi->igi_flags & IGIF_LOOPBACK) {
  736                 CTR2(KTR_IGMPV3, "ignore v1 query on IGIF_LOOPBACK ifp %p(%s)",
  737                     ifp, ifp->if_xname);
  738                 goto out_locked;
  739         }
  740 
  741         /*
  742          * Switch to IGMPv1 host compatibility mode.
  743          */
  744         igmp_set_version(igi, IGMP_VERSION_1);
  745 
  746         CTR2(KTR_IGMPV3, "process v1 query on ifp %p(%s)", ifp, ifp->if_xname);
  747 
  748         /*
  749          * Start the timers in all of our group records
  750          * for the interface on which the query arrived,
  751          * except those which are already running.
  752          */
  753         IF_ADDR_RLOCK(ifp);
  754         TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
  755                 if (ifma->ifma_addr->sa_family != AF_INET ||
  756                     ifma->ifma_protospec == NULL)
  757                         continue;
  758                 inm = (struct in_multi *)ifma->ifma_protospec;
  759                 if (inm->inm_timer != 0)
  760                         continue;
  761                 switch (inm->inm_state) {
  762                 case IGMP_NOT_MEMBER:
  763                 case IGMP_SILENT_MEMBER:
  764                         break;
  765                 case IGMP_G_QUERY_PENDING_MEMBER:
  766                 case IGMP_SG_QUERY_PENDING_MEMBER:
  767                 case IGMP_REPORTING_MEMBER:
  768                 case IGMP_IDLE_MEMBER:
  769                 case IGMP_LAZY_MEMBER:
  770                 case IGMP_SLEEPING_MEMBER:
  771                 case IGMP_AWAKENING_MEMBER:
  772                         inm->inm_state = IGMP_REPORTING_MEMBER;
  773                         inm->inm_timer = IGMP_RANDOM_DELAY(
  774                             IGMP_V1V2_MAX_RI * PR_FASTHZ);
  775                         V_current_state_timers_running = 1;
  776                         break;
  777                 case IGMP_LEAVING_MEMBER:
  778                         break;
  779                 }
  780         }
  781         IF_ADDR_RUNLOCK(ifp);
  782 
  783 out_locked:
  784         IGMP_UNLOCK();
  785         IN_MULTI_UNLOCK();
  786 
  787         return (0);
  788 }
  789 
  790 /*
  791  * Process a received IGMPv2 general or group-specific query.
  792  */
  793 static int
  794 igmp_input_v2_query(struct ifnet *ifp, const struct ip *ip,
  795     const struct igmp *igmp)
  796 {
  797         struct ifmultiaddr      *ifma;
  798         struct igmp_ifinfo      *igi;
  799         struct in_multi         *inm;
  800         int                      is_general_query;
  801         uint16_t                 timer;
  802 
  803         is_general_query = 0;
  804 
  805         /*
  806          * Validate address fields upfront.
  807          * XXX SMPng: unlocked increments in igmpstat assumed atomic.
  808          */
  809         if (in_nullhost(igmp->igmp_group)) {
  810                 /*
  811                  * IGMPv2 General Query.
  812                  * If this was not sent to the all-hosts group, ignore it.
  813                  */
  814                 if (!in_allhosts(ip->ip_dst))
  815                         return (0);
  816                 IGMPSTAT_INC(igps_rcv_gen_queries);
  817                 is_general_query = 1;
  818         } else {
  819                 /* IGMPv2 Group-Specific Query. */
  820                 IGMPSTAT_INC(igps_rcv_group_queries);
  821         }
  822 
  823         IN_MULTI_LOCK();
  824         IGMP_LOCK();
  825 
  826         igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
  827         KASSERT(igi != NULL, ("%s: no igmp_ifinfo for ifp %p", __func__, ifp));
  828 
  829         if (igi->igi_flags & IGIF_LOOPBACK) {
  830                 CTR2(KTR_IGMPV3, "ignore v2 query on IGIF_LOOPBACK ifp %p(%s)",
  831                     ifp, ifp->if_xname);
  832                 goto out_locked;
  833         }
  834 
  835         /*
  836          * Ignore v2 query if in v1 Compatibility Mode.
  837          */
  838         if (igi->igi_version == IGMP_VERSION_1)
  839                 goto out_locked;
  840 
  841         igmp_set_version(igi, IGMP_VERSION_2);
  842 
  843         timer = igmp->igmp_code * PR_FASTHZ / IGMP_TIMER_SCALE;
  844         if (timer == 0)
  845                 timer = 1;
  846 
  847         if (is_general_query) {
  848                 /*
  849                  * For each reporting group joined on this
  850                  * interface, kick the report timer.
  851                  */
  852                 CTR2(KTR_IGMPV3, "process v2 general query on ifp %p(%s)",
  853                     ifp, ifp->if_xname);
  854                 IF_ADDR_RLOCK(ifp);
  855                 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
  856                         if (ifma->ifma_addr->sa_family != AF_INET ||
  857                             ifma->ifma_protospec == NULL)
  858                                 continue;
  859                         inm = (struct in_multi *)ifma->ifma_protospec;
  860                         igmp_v2_update_group(inm, timer);
  861                 }
  862                 IF_ADDR_RUNLOCK(ifp);
  863         } else {
  864                 /*
  865                  * Group-specific IGMPv2 query, we need only
  866                  * look up the single group to process it.
  867                  */
  868                 inm = inm_lookup(ifp, igmp->igmp_group);
  869                 if (inm != NULL) {
  870                         CTR3(KTR_IGMPV3, "process v2 query %s on ifp %p(%s)",
  871                             inet_ntoa(igmp->igmp_group), ifp, ifp->if_xname);
  872                         igmp_v2_update_group(inm, timer);
  873                 }
  874         }
  875 
  876 out_locked:
  877         IGMP_UNLOCK();
  878         IN_MULTI_UNLOCK();
  879 
  880         return (0);
  881 }
  882 
  883 /*
  884  * Update the report timer on a group in response to an IGMPv2 query.
  885  *
  886  * If we are becoming the reporting member for this group, start the timer.
  887  * If we already are the reporting member for this group, and timer is
  888  * below the threshold, reset it.
  889  *
  890  * We may be updating the group for the first time since we switched
  891  * to IGMPv3. If we are, then we must clear any recorded source lists,
  892  * and transition to REPORTING state; the group timer is overloaded
  893  * for group and group-source query responses. 
  894  *
  895  * Unlike IGMPv3, the delay per group should be jittered
  896  * to avoid bursts of IGMPv2 reports.
  897  */
  898 static void
  899 igmp_v2_update_group(struct in_multi *inm, const int timer)
  900 {
  901 
  902         CTR4(KTR_IGMPV3, "%s: %s/%s timer=%d", __func__,
  903             inet_ntoa(inm->inm_addr), inm->inm_ifp->if_xname, timer);
  904 
  905         IN_MULTI_LOCK_ASSERT();
  906 
  907         switch (inm->inm_state) {
  908         case IGMP_NOT_MEMBER:
  909         case IGMP_SILENT_MEMBER:
  910                 break;
  911         case IGMP_REPORTING_MEMBER:
  912                 if (inm->inm_timer != 0 &&
  913                     inm->inm_timer <= timer) {
  914                         CTR1(KTR_IGMPV3, "%s: REPORTING and timer running, "
  915                             "skipping.", __func__);
  916                         break;
  917                 }
  918                 /* FALLTHROUGH */
  919         case IGMP_SG_QUERY_PENDING_MEMBER:
  920         case IGMP_G_QUERY_PENDING_MEMBER:
  921         case IGMP_IDLE_MEMBER:
  922         case IGMP_LAZY_MEMBER:
  923         case IGMP_AWAKENING_MEMBER:
  924                 CTR1(KTR_IGMPV3, "%s: ->REPORTING", __func__);
  925                 inm->inm_state = IGMP_REPORTING_MEMBER;
  926                 inm->inm_timer = IGMP_RANDOM_DELAY(timer);
  927                 V_current_state_timers_running = 1;
  928                 break;
  929         case IGMP_SLEEPING_MEMBER:
  930                 CTR1(KTR_IGMPV3, "%s: ->AWAKENING", __func__);
  931                 inm->inm_state = IGMP_AWAKENING_MEMBER;
  932                 break;
  933         case IGMP_LEAVING_MEMBER:
  934                 break;
  935         }
  936 }
  937 
  938 /*
  939  * Process a received IGMPv3 general, group-specific or
  940  * group-and-source-specific query.
  941  * Assumes m has already been pulled up to the full IGMP message length.
  942  * Return 0 if successful, otherwise an appropriate error code is returned.
  943  */
  944 static int
  945 igmp_input_v3_query(struct ifnet *ifp, const struct ip *ip,
  946     /*const*/ struct igmpv3 *igmpv3)
  947 {
  948         struct igmp_ifinfo      *igi;
  949         struct in_multi         *inm;
  950         int                      is_general_query;
  951         uint32_t                 maxresp, nsrc, qqi;
  952         uint16_t                 timer;
  953         uint8_t                  qrv;
  954 
  955         is_general_query = 0;
  956 
  957         CTR2(KTR_IGMPV3, "process v3 query on ifp %p(%s)", ifp, ifp->if_xname);
  958 
  959         maxresp = igmpv3->igmp_code;    /* in 1/10ths of a second */
  960         if (maxresp >= 128) {
  961                 maxresp = IGMP_MANT(igmpv3->igmp_code) <<
  962                           (IGMP_EXP(igmpv3->igmp_code) + 3);
  963         }
  964 
  965         /*
  966          * Robustness must never be less than 2 for on-wire IGMPv3.
  967          * FUTURE: Check if ifp has IGIF_LOOPBACK set, as we will make
  968          * an exception for interfaces whose IGMPv3 state changes
  969          * are redirected to loopback (e.g. MANET).
  970          */
  971         qrv = IGMP_QRV(igmpv3->igmp_misc);
  972         if (qrv < 2) {
  973                 CTR3(KTR_IGMPV3, "%s: clamping qrv %d to %d", __func__,
  974                     qrv, IGMP_RV_INIT);
  975                 qrv = IGMP_RV_INIT;
  976         }
  977 
  978         qqi = igmpv3->igmp_qqi;
  979         if (qqi >= 128) {
  980                 qqi = IGMP_MANT(igmpv3->igmp_qqi) <<
  981                      (IGMP_EXP(igmpv3->igmp_qqi) + 3);
  982         }
  983 
  984         timer = maxresp * PR_FASTHZ / IGMP_TIMER_SCALE;
  985         if (timer == 0)
  986                 timer = 1;
  987 
  988         nsrc = ntohs(igmpv3->igmp_numsrc);
  989 
  990         /*
  991          * Validate address fields and versions upfront before
  992          * accepting v3 query.
  993          * XXX SMPng: Unlocked access to igmpstat counters here.
  994          */
  995         if (in_nullhost(igmpv3->igmp_group)) {
  996                 /*
  997                  * IGMPv3 General Query.
  998                  *
  999                  * General Queries SHOULD be directed to 224.0.0.1.
 1000                  * A general query with a source list has undefined
 1001                  * behaviour; discard it.
 1002                  */
 1003                 IGMPSTAT_INC(igps_rcv_gen_queries);
 1004                 if (!in_allhosts(ip->ip_dst) || nsrc > 0) {
 1005                         IGMPSTAT_INC(igps_rcv_badqueries);
 1006                         return (0);
 1007                 }
 1008                 is_general_query = 1;
 1009         } else {
 1010                 /* Group or group-source specific query. */
 1011                 if (nsrc == 0)
 1012                         IGMPSTAT_INC(igps_rcv_group_queries);
 1013                 else
 1014                         IGMPSTAT_INC(igps_rcv_gsr_queries);
 1015         }
 1016 
 1017         IN_MULTI_LOCK();
 1018         IGMP_LOCK();
 1019 
 1020         igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
 1021         KASSERT(igi != NULL, ("%s: no igmp_ifinfo for ifp %p", __func__, ifp));
 1022 
 1023         if (igi->igi_flags & IGIF_LOOPBACK) {
 1024                 CTR2(KTR_IGMPV3, "ignore v3 query on IGIF_LOOPBACK ifp %p(%s)",
 1025                     ifp, ifp->if_xname);
 1026                 goto out_locked;
 1027         }
 1028 
 1029         /*
 1030          * Discard the v3 query if we're in Compatibility Mode.
 1031          * The RFC is not obviously worded that hosts need to stay in
 1032          * compatibility mode until the Old Version Querier Present
 1033          * timer expires.
 1034          */
 1035         if (igi->igi_version != IGMP_VERSION_3) {
 1036                 CTR3(KTR_IGMPV3, "ignore v3 query in v%d mode on ifp %p(%s)",
 1037                     igi->igi_version, ifp, ifp->if_xname);
 1038                 goto out_locked;
 1039         }
 1040 
 1041         igmp_set_version(igi, IGMP_VERSION_3);
 1042         igi->igi_rv = qrv;
 1043         igi->igi_qi = qqi;
 1044         igi->igi_qri = maxresp;
 1045 
 1046         CTR4(KTR_IGMPV3, "%s: qrv %d qi %d qri %d", __func__, qrv, qqi,
 1047             maxresp);
 1048 
 1049         if (is_general_query) {
 1050                 /*
 1051                  * Schedule a current-state report on this ifp for
 1052                  * all groups, possibly containing source lists.
 1053                  * If there is a pending General Query response
 1054                  * scheduled earlier than the selected delay, do
 1055                  * not schedule any other reports.
 1056                  * Otherwise, reset the interface timer.
 1057                  */
 1058                 CTR2(KTR_IGMPV3, "process v3 general query on ifp %p(%s)",
 1059                     ifp, ifp->if_xname);
 1060                 if (igi->igi_v3_timer == 0 || igi->igi_v3_timer >= timer) {
 1061                         igi->igi_v3_timer = IGMP_RANDOM_DELAY(timer);
 1062                         V_interface_timers_running = 1;
 1063                 }
 1064         } else {
 1065                 /*
 1066                  * Group-source-specific queries are throttled on
 1067                  * a per-group basis to defeat denial-of-service attempts.
 1068                  * Queries for groups we are not a member of on this
 1069                  * link are simply ignored.
 1070                  */
 1071                 inm = inm_lookup(ifp, igmpv3->igmp_group);
 1072                 if (inm == NULL)
 1073                         goto out_locked;
 1074                 if (nsrc > 0) {
 1075                         if (!ratecheck(&inm->inm_lastgsrtv,
 1076                             &V_igmp_gsrdelay)) {
 1077                                 CTR1(KTR_IGMPV3, "%s: GS query throttled.",
 1078                                     __func__);
 1079                                 IGMPSTAT_INC(igps_drop_gsr_queries);
 1080                                 goto out_locked;
 1081                         }
 1082                 }
 1083                 CTR3(KTR_IGMPV3, "process v3 %s query on ifp %p(%s)",
 1084                      inet_ntoa(igmpv3->igmp_group), ifp, ifp->if_xname);
 1085                 /*
 1086                  * If there is a pending General Query response
 1087                  * scheduled sooner than the selected delay, no
 1088                  * further report need be scheduled.
 1089                  * Otherwise, prepare to respond to the
 1090                  * group-specific or group-and-source query.
 1091                  */
 1092                 if (igi->igi_v3_timer == 0 || igi->igi_v3_timer >= timer)
 1093                         igmp_input_v3_group_query(inm, igi, timer, igmpv3);
 1094         }
 1095 
 1096 out_locked:
 1097         IGMP_UNLOCK();
 1098         IN_MULTI_UNLOCK();
 1099 
 1100         return (0);
 1101 }
 1102 
 1103 /*
 1104  * Process a recieved IGMPv3 group-specific or group-and-source-specific
 1105  * query.
 1106  * Return <0 if any error occured. Currently this is ignored.
 1107  */
 1108 static int
 1109 igmp_input_v3_group_query(struct in_multi *inm, struct igmp_ifinfo *igi,
 1110     int timer, /*const*/ struct igmpv3 *igmpv3)
 1111 {
 1112         int                      retval;
 1113         uint16_t                 nsrc;
 1114 
 1115         IN_MULTI_LOCK_ASSERT();
 1116         IGMP_LOCK_ASSERT();
 1117 
 1118         retval = 0;
 1119 
 1120         switch (inm->inm_state) {
 1121         case IGMP_NOT_MEMBER:
 1122         case IGMP_SILENT_MEMBER:
 1123         case IGMP_SLEEPING_MEMBER:
 1124         case IGMP_LAZY_MEMBER:
 1125         case IGMP_AWAKENING_MEMBER:
 1126         case IGMP_IDLE_MEMBER:
 1127         case IGMP_LEAVING_MEMBER:
 1128                 return (retval);
 1129                 break;
 1130         case IGMP_REPORTING_MEMBER:
 1131         case IGMP_G_QUERY_PENDING_MEMBER:
 1132         case IGMP_SG_QUERY_PENDING_MEMBER:
 1133                 break;
 1134         }
 1135 
 1136         nsrc = ntohs(igmpv3->igmp_numsrc);
 1137 
 1138         /*
 1139          * Deal with group-specific queries upfront.
 1140          * If any group query is already pending, purge any recorded
 1141          * source-list state if it exists, and schedule a query response
 1142          * for this group-specific query.
 1143          */
 1144         if (nsrc == 0) {
 1145                 if (inm->inm_state == IGMP_G_QUERY_PENDING_MEMBER ||
 1146                     inm->inm_state == IGMP_SG_QUERY_PENDING_MEMBER) {
 1147                         inm_clear_recorded(inm);
 1148                         timer = min(inm->inm_timer, timer);
 1149                 }
 1150                 inm->inm_state = IGMP_G_QUERY_PENDING_MEMBER;
 1151                 inm->inm_timer = IGMP_RANDOM_DELAY(timer);
 1152                 V_current_state_timers_running = 1;
 1153                 return (retval);
 1154         }
 1155 
 1156         /*
 1157          * Deal with the case where a group-and-source-specific query has
 1158          * been received but a group-specific query is already pending.
 1159          */
 1160         if (inm->inm_state == IGMP_G_QUERY_PENDING_MEMBER) {
 1161                 timer = min(inm->inm_timer, timer);
 1162                 inm->inm_timer = IGMP_RANDOM_DELAY(timer);
 1163                 V_current_state_timers_running = 1;
 1164                 return (retval);
 1165         }
 1166 
 1167         /*
 1168          * Finally, deal with the case where a group-and-source-specific
 1169          * query has been received, where a response to a previous g-s-r
 1170          * query exists, or none exists.
 1171          * In this case, we need to parse the source-list which the Querier
 1172          * has provided us with and check if we have any source list filter
 1173          * entries at T1 for these sources. If we do not, there is no need
 1174          * schedule a report and the query may be dropped.
 1175          * If we do, we must record them and schedule a current-state
 1176          * report for those sources.
 1177          * FIXME: Handling source lists larger than 1 mbuf requires that
 1178          * we pass the mbuf chain pointer down to this function, and use
 1179          * m_getptr() to walk the chain.
 1180          */
 1181         if (inm->inm_nsrc > 0) {
 1182                 const struct in_addr    *ap;
 1183                 int                      i, nrecorded;
 1184 
 1185                 ap = (const struct in_addr *)(igmpv3 + 1);
 1186                 nrecorded = 0;
 1187                 for (i = 0; i < nsrc; i++, ap++) {
 1188                         retval = inm_record_source(inm, ap->s_addr);
 1189                         if (retval < 0)
 1190                                 break;
 1191                         nrecorded += retval;
 1192                 }
 1193                 if (nrecorded > 0) {
 1194                         CTR1(KTR_IGMPV3,
 1195                             "%s: schedule response to SG query", __func__);
 1196                         inm->inm_state = IGMP_SG_QUERY_PENDING_MEMBER;
 1197                         inm->inm_timer = IGMP_RANDOM_DELAY(timer);
 1198                         V_current_state_timers_running = 1;
 1199                 }
 1200         }
 1201 
 1202         return (retval);
 1203 }
 1204 
 1205 /*
 1206  * Process a received IGMPv1 host membership report.
 1207  *
 1208  * NOTE: 0.0.0.0 workaround breaks const correctness.
 1209  */
 1210 static int
 1211 igmp_input_v1_report(struct ifnet *ifp, /*const*/ struct ip *ip,
 1212     /*const*/ struct igmp *igmp)
 1213 {
 1214         struct in_ifaddr *ia;
 1215         struct in_multi *inm;
 1216 
 1217         IGMPSTAT_INC(igps_rcv_reports);
 1218 
 1219         if (ifp->if_flags & IFF_LOOPBACK)
 1220                 return (0);
 1221 
 1222         if (!IN_MULTICAST(ntohl(igmp->igmp_group.s_addr)) ||
 1223             !in_hosteq(igmp->igmp_group, ip->ip_dst)) {
 1224                 IGMPSTAT_INC(igps_rcv_badreports);
 1225                 return (EINVAL);
 1226         }
 1227 
 1228         /*
 1229          * RFC 3376, Section 4.2.13, 9.2, 9.3:
 1230          * Booting clients may use the source address 0.0.0.0. Some
 1231          * IGMP daemons may not know how to use IP_RECVIF to determine
 1232          * the interface upon which this message was received.
 1233          * Replace 0.0.0.0 with the subnet address if told to do so.
 1234          */
 1235         if (V_igmp_recvifkludge && in_nullhost(ip->ip_src)) {
 1236                 IFP_TO_IA(ifp, ia);
 1237                 if (ia != NULL) {
 1238                         ip->ip_src.s_addr = htonl(ia->ia_subnet);
 1239                         ifa_free(&ia->ia_ifa);
 1240                 }
 1241         }
 1242 
 1243         CTR3(KTR_IGMPV3, "process v1 report %s on ifp %p(%s)",
 1244              inet_ntoa(igmp->igmp_group), ifp, ifp->if_xname);
 1245 
 1246         /*
 1247          * IGMPv1 report suppression.
 1248          * If we are a member of this group, and our membership should be
 1249          * reported, stop our group timer and transition to the 'lazy' state.
 1250          */
 1251         IN_MULTI_LOCK();
 1252         inm = inm_lookup(ifp, igmp->igmp_group);
 1253         if (inm != NULL) {
 1254                 struct igmp_ifinfo *igi;
 1255 
 1256                 igi = inm->inm_igi;
 1257                 if (igi == NULL) {
 1258                         KASSERT(igi != NULL,
 1259                             ("%s: no igi for ifp %p", __func__, ifp));
 1260                         goto out_locked;
 1261                 }
 1262 
 1263                 IGMPSTAT_INC(igps_rcv_ourreports);
 1264 
 1265                 /*
 1266                  * If we are in IGMPv3 host mode, do not allow the
 1267                  * other host's IGMPv1 report to suppress our reports
 1268                  * unless explicitly configured to do so.
 1269                  */
 1270                 if (igi->igi_version == IGMP_VERSION_3) {
 1271                         if (V_igmp_legacysupp)
 1272                                 igmp_v3_suppress_group_record(inm);
 1273                         goto out_locked;
 1274                 }
 1275 
 1276                 inm->inm_timer = 0;
 1277 
 1278                 switch (inm->inm_state) {
 1279                 case IGMP_NOT_MEMBER:
 1280                 case IGMP_SILENT_MEMBER:
 1281                         break;
 1282                 case IGMP_IDLE_MEMBER:
 1283                 case IGMP_LAZY_MEMBER:
 1284                 case IGMP_AWAKENING_MEMBER:
 1285                         CTR3(KTR_IGMPV3,
 1286                             "report suppressed for %s on ifp %p(%s)",
 1287                             inet_ntoa(igmp->igmp_group), ifp, ifp->if_xname);
 1288                 case IGMP_SLEEPING_MEMBER:
 1289                         inm->inm_state = IGMP_SLEEPING_MEMBER;
 1290                         break;
 1291                 case IGMP_REPORTING_MEMBER:
 1292                         CTR3(KTR_IGMPV3,
 1293                             "report suppressed for %s on ifp %p(%s)",
 1294                             inet_ntoa(igmp->igmp_group), ifp, ifp->if_xname);
 1295                         if (igi->igi_version == IGMP_VERSION_1)
 1296                                 inm->inm_state = IGMP_LAZY_MEMBER;
 1297                         else if (igi->igi_version == IGMP_VERSION_2)
 1298                                 inm->inm_state = IGMP_SLEEPING_MEMBER;
 1299                         break;
 1300                 case IGMP_G_QUERY_PENDING_MEMBER:
 1301                 case IGMP_SG_QUERY_PENDING_MEMBER:
 1302                 case IGMP_LEAVING_MEMBER:
 1303                         break;
 1304                 }
 1305         }
 1306 
 1307 out_locked:
 1308         IN_MULTI_UNLOCK();
 1309 
 1310         return (0);
 1311 }
 1312 
 1313 /*
 1314  * Process a received IGMPv2 host membership report.
 1315  *
 1316  * NOTE: 0.0.0.0 workaround breaks const correctness.
 1317  */
 1318 static int
 1319 igmp_input_v2_report(struct ifnet *ifp, /*const*/ struct ip *ip,
 1320     /*const*/ struct igmp *igmp)
 1321 {
 1322         struct in_ifaddr *ia;
 1323         struct in_multi *inm;
 1324 
 1325         /*
 1326          * Make sure we don't hear our own membership report.  Fast
 1327          * leave requires knowing that we are the only member of a
 1328          * group.
 1329          */
 1330         IFP_TO_IA(ifp, ia);
 1331         if (ia != NULL && in_hosteq(ip->ip_src, IA_SIN(ia)->sin_addr)) {
 1332                 ifa_free(&ia->ia_ifa);
 1333                 return (0);
 1334         }
 1335 
 1336         IGMPSTAT_INC(igps_rcv_reports);
 1337 
 1338         if (ifp->if_flags & IFF_LOOPBACK) {
 1339                 if (ia != NULL)
 1340                         ifa_free(&ia->ia_ifa);
 1341                 return (0);
 1342         }
 1343 
 1344         if (!IN_MULTICAST(ntohl(igmp->igmp_group.s_addr)) ||
 1345             !in_hosteq(igmp->igmp_group, ip->ip_dst)) {
 1346                 if (ia != NULL)
 1347                         ifa_free(&ia->ia_ifa);
 1348                 IGMPSTAT_INC(igps_rcv_badreports);
 1349                 return (EINVAL);
 1350         }
 1351 
 1352         /*
 1353          * RFC 3376, Section 4.2.13, 9.2, 9.3:
 1354          * Booting clients may use the source address 0.0.0.0. Some
 1355          * IGMP daemons may not know how to use IP_RECVIF to determine
 1356          * the interface upon which this message was received.
 1357          * Replace 0.0.0.0 with the subnet address if told to do so.
 1358          */
 1359         if (V_igmp_recvifkludge && in_nullhost(ip->ip_src)) {
 1360                 if (ia != NULL)
 1361                         ip->ip_src.s_addr = htonl(ia->ia_subnet);
 1362         }
 1363         if (ia != NULL)
 1364                 ifa_free(&ia->ia_ifa);
 1365 
 1366         CTR3(KTR_IGMPV3, "process v2 report %s on ifp %p(%s)",
 1367              inet_ntoa(igmp->igmp_group), ifp, ifp->if_xname);
 1368 
 1369         /*
 1370          * IGMPv2 report suppression.
 1371          * If we are a member of this group, and our membership should be
 1372          * reported, and our group timer is pending or about to be reset,
 1373          * stop our group timer by transitioning to the 'lazy' state.
 1374          */
 1375         IN_MULTI_LOCK();
 1376         inm = inm_lookup(ifp, igmp->igmp_group);
 1377         if (inm != NULL) {
 1378                 struct igmp_ifinfo *igi;
 1379 
 1380                 igi = inm->inm_igi;
 1381                 KASSERT(igi != NULL, ("%s: no igi for ifp %p", __func__, ifp));
 1382 
 1383                 IGMPSTAT_INC(igps_rcv_ourreports);
 1384 
 1385                 /*
 1386                  * If we are in IGMPv3 host mode, do not allow the
 1387                  * other host's IGMPv1 report to suppress our reports
 1388                  * unless explicitly configured to do so.
 1389                  */
 1390                 if (igi->igi_version == IGMP_VERSION_3) {
 1391                         if (V_igmp_legacysupp)
 1392                                 igmp_v3_suppress_group_record(inm);
 1393                         goto out_locked;
 1394                 }
 1395 
 1396                 inm->inm_timer = 0;
 1397 
 1398                 switch (inm->inm_state) {
 1399                 case IGMP_NOT_MEMBER:
 1400                 case IGMP_SILENT_MEMBER:
 1401                 case IGMP_SLEEPING_MEMBER:
 1402                         break;
 1403                 case IGMP_REPORTING_MEMBER:
 1404                 case IGMP_IDLE_MEMBER:
 1405                 case IGMP_AWAKENING_MEMBER:
 1406                         CTR3(KTR_IGMPV3,
 1407                             "report suppressed for %s on ifp %p(%s)",
 1408                             inet_ntoa(igmp->igmp_group), ifp, ifp->if_xname);
 1409                 case IGMP_LAZY_MEMBER:
 1410                         inm->inm_state = IGMP_LAZY_MEMBER;
 1411                         break;
 1412                 case IGMP_G_QUERY_PENDING_MEMBER:
 1413                 case IGMP_SG_QUERY_PENDING_MEMBER:
 1414                 case IGMP_LEAVING_MEMBER:
 1415                         break;
 1416                 }
 1417         }
 1418 
 1419 out_locked:
 1420         IN_MULTI_UNLOCK();
 1421 
 1422         return (0);
 1423 }
 1424 
 1425 void
 1426 igmp_input(struct mbuf *m, int off)
 1427 {
 1428         int iphlen;
 1429         struct ifnet *ifp;
 1430         struct igmp *igmp;
 1431         struct ip *ip;
 1432         int igmplen;
 1433         int minlen;
 1434         int queryver;
 1435 
 1436         CTR3(KTR_IGMPV3, "%s: called w/mbuf (%p,%d)", __func__, m, off);
 1437 
 1438         ifp = m->m_pkthdr.rcvif;
 1439 
 1440         IGMPSTAT_INC(igps_rcv_total);
 1441 
 1442         ip = mtod(m, struct ip *);
 1443         iphlen = off;
 1444         igmplen = ip->ip_len;
 1445 
 1446         /*
 1447          * Validate lengths.
 1448          */
 1449         if (igmplen < IGMP_MINLEN) {
 1450                 IGMPSTAT_INC(igps_rcv_tooshort);
 1451                 m_freem(m);
 1452                 return;
 1453         }
 1454 
 1455         /*
 1456          * Always pullup to the minimum size for v1/v2 or v3
 1457          * to amortize calls to m_pullup().
 1458          */
 1459         minlen = iphlen;
 1460         if (igmplen >= IGMP_V3_QUERY_MINLEN)
 1461                 minlen += IGMP_V3_QUERY_MINLEN;
 1462         else
 1463                 minlen += IGMP_MINLEN;
 1464         if ((m->m_flags & M_EXT || m->m_len < minlen) &&
 1465             (m = m_pullup(m, minlen)) == 0) {
 1466                 IGMPSTAT_INC(igps_rcv_tooshort);
 1467                 return;
 1468         }
 1469         ip = mtod(m, struct ip *);
 1470 
 1471         /*
 1472          * Validate checksum.
 1473          */
 1474         m->m_data += iphlen;
 1475         m->m_len -= iphlen;
 1476         igmp = mtod(m, struct igmp *);
 1477         if (in_cksum(m, igmplen)) {
 1478                 IGMPSTAT_INC(igps_rcv_badsum);
 1479                 m_freem(m);
 1480                 return;
 1481         }
 1482         m->m_data -= iphlen;
 1483         m->m_len += iphlen;
 1484 
 1485         /*
 1486          * IGMP control traffic is link-scope, and must have a TTL of 1.
 1487          * DVMRP traffic (e.g. mrinfo, mtrace) is an exception;
 1488          * probe packets may come from beyond the LAN.
 1489          */
 1490         if (igmp->igmp_type != IGMP_DVMRP && ip->ip_ttl != 1) {
 1491                 IGMPSTAT_INC(igps_rcv_badttl);
 1492                 m_freem(m);
 1493                 return;
 1494         }
 1495 
 1496         switch (igmp->igmp_type) {
 1497         case IGMP_HOST_MEMBERSHIP_QUERY:
 1498                 if (igmplen == IGMP_MINLEN) {
 1499                         if (igmp->igmp_code == 0)
 1500                                 queryver = IGMP_VERSION_1;
 1501                         else
 1502                                 queryver = IGMP_VERSION_2;
 1503                 } else if (igmplen >= IGMP_V3_QUERY_MINLEN) {
 1504                         queryver = IGMP_VERSION_3;
 1505                 } else {
 1506                         IGMPSTAT_INC(igps_rcv_tooshort);
 1507                         m_freem(m);
 1508                         return;
 1509                 }
 1510 
 1511                 switch (queryver) {
 1512                 case IGMP_VERSION_1:
 1513                         IGMPSTAT_INC(igps_rcv_v1v2_queries);
 1514                         if (!V_igmp_v1enable)
 1515                                 break;
 1516                         if (igmp_input_v1_query(ifp, ip, igmp) != 0) {
 1517                                 m_freem(m);
 1518                                 return;
 1519                         }
 1520                         break;
 1521 
 1522                 case IGMP_VERSION_2:
 1523                         IGMPSTAT_INC(igps_rcv_v1v2_queries);
 1524                         if (!V_igmp_v2enable)
 1525                                 break;
 1526                         if (igmp_input_v2_query(ifp, ip, igmp) != 0) {
 1527                                 m_freem(m);
 1528                                 return;
 1529                         }
 1530                         break;
 1531 
 1532                 case IGMP_VERSION_3: {
 1533                                 struct igmpv3 *igmpv3;
 1534                                 uint16_t igmpv3len;
 1535                                 uint16_t nsrc;
 1536 
 1537                                 IGMPSTAT_INC(igps_rcv_v3_queries);
 1538                                 igmpv3 = (struct igmpv3 *)igmp;
 1539                                 /*
 1540                                  * Validate length based on source count.
 1541                                  */
 1542                                 nsrc = ntohs(igmpv3->igmp_numsrc);
 1543                                 if (nsrc * sizeof(in_addr_t) >
 1544                                     UINT16_MAX - iphlen - IGMP_V3_QUERY_MINLEN) {
 1545                                         IGMPSTAT_INC(igps_rcv_tooshort);
 1546                                         return;
 1547                                 }
 1548                                 /*
 1549                                  * m_pullup() may modify m, so pullup in
 1550                                  * this scope.
 1551                                  */
 1552                                 igmpv3len = iphlen + IGMP_V3_QUERY_MINLEN +
 1553                                     sizeof(struct in_addr) * nsrc;
 1554                                 if ((m->m_flags & M_EXT ||
 1555                                      m->m_len < igmpv3len) &&
 1556                                     (m = m_pullup(m, igmpv3len)) == NULL) {
 1557                                         IGMPSTAT_INC(igps_rcv_tooshort);
 1558                                         return;
 1559                                 }
 1560                                 igmpv3 = (struct igmpv3 *)(mtod(m, uint8_t *)
 1561                                     + iphlen);
 1562                                 if (igmp_input_v3_query(ifp, ip, igmpv3) != 0) {
 1563                                         m_freem(m);
 1564                                         return;
 1565                                 }
 1566                         }
 1567                         break;
 1568                 }
 1569                 break;
 1570 
 1571         case IGMP_v1_HOST_MEMBERSHIP_REPORT:
 1572                 if (!V_igmp_v1enable)
 1573                         break;
 1574                 if (igmp_input_v1_report(ifp, ip, igmp) != 0) {
 1575                         m_freem(m);
 1576                         return;
 1577                 }
 1578                 break;
 1579 
 1580         case IGMP_v2_HOST_MEMBERSHIP_REPORT:
 1581                 if (!V_igmp_v2enable)
 1582                         break;
 1583                 if (!ip_checkrouteralert(m))
 1584                         IGMPSTAT_INC(igps_rcv_nora);
 1585                 if (igmp_input_v2_report(ifp, ip, igmp) != 0) {
 1586                         m_freem(m);
 1587                         return;
 1588                 }
 1589                 break;
 1590 
 1591         case IGMP_v3_HOST_MEMBERSHIP_REPORT:
 1592                 /*
 1593                  * Hosts do not need to process IGMPv3 membership reports,
 1594                  * as report suppression is no longer required.
 1595                  */
 1596                 if (!ip_checkrouteralert(m))
 1597                         IGMPSTAT_INC(igps_rcv_nora);
 1598                 break;
 1599 
 1600         default:
 1601                 break;
 1602         }
 1603 
 1604         /*
 1605          * Pass all valid IGMP packets up to any process(es) listening on a
 1606          * raw IGMP socket.
 1607          */
 1608         rip_input(m, off);
 1609 }
 1610 
 1611 
 1612 /*
 1613  * Fast timeout handler (global).
 1614  * VIMAGE: Timeout handlers are expected to service all vimages.
 1615  */
 1616 void
 1617 igmp_fasttimo(void)
 1618 {
 1619         VNET_ITERATOR_DECL(vnet_iter);
 1620 
 1621         VNET_LIST_RLOCK_NOSLEEP();
 1622         VNET_FOREACH(vnet_iter) {
 1623                 CURVNET_SET(vnet_iter);
 1624                 igmp_fasttimo_vnet();
 1625                 CURVNET_RESTORE();
 1626         }
 1627         VNET_LIST_RUNLOCK_NOSLEEP();
 1628 }
 1629 
 1630 /*
 1631  * Fast timeout handler (per-vnet).
 1632  * Sends are shuffled off to a netisr to deal with Giant.
 1633  *
 1634  * VIMAGE: Assume caller has set up our curvnet.
 1635  */
 1636 static void
 1637 igmp_fasttimo_vnet(void)
 1638 {
 1639         struct ifqueue           scq;   /* State-change packets */
 1640         struct ifqueue           qrq;   /* Query response packets */
 1641         struct ifnet            *ifp;
 1642         struct igmp_ifinfo      *igi;
 1643         struct ifmultiaddr      *ifma;
 1644         struct in_multi         *inm;
 1645         int                      loop, uri_fasthz;
 1646 
 1647         loop = 0;
 1648         uri_fasthz = 0;
 1649 
 1650         /*
 1651          * Quick check to see if any work needs to be done, in order to
 1652          * minimize the overhead of fasttimo processing.
 1653          * SMPng: XXX Unlocked reads.
 1654          */
 1655         if (!V_current_state_timers_running &&
 1656             !V_interface_timers_running &&
 1657             !V_state_change_timers_running)
 1658                 return;
 1659 
 1660         IN_MULTI_LOCK();
 1661         IGMP_LOCK();
 1662 
 1663         /*
 1664          * IGMPv3 General Query response timer processing.
 1665          */
 1666         if (V_interface_timers_running) {
 1667                 CTR1(KTR_IGMPV3, "%s: interface timers running", __func__);
 1668 
 1669                 V_interface_timers_running = 0;
 1670                 LIST_FOREACH(igi, &V_igi_head, igi_link) {
 1671                         if (igi->igi_v3_timer == 0) {
 1672                                 /* Do nothing. */
 1673                         } else if (--igi->igi_v3_timer == 0) {
 1674                                 igmp_v3_dispatch_general_query(igi);
 1675                         } else {
 1676                                 V_interface_timers_running = 1;
 1677                         }
 1678                 }
 1679         }
 1680 
 1681         if (!V_current_state_timers_running &&
 1682             !V_state_change_timers_running)
 1683                 goto out_locked;
 1684 
 1685         V_current_state_timers_running = 0;
 1686         V_state_change_timers_running = 0;
 1687 
 1688         CTR1(KTR_IGMPV3, "%s: state change timers running", __func__);
 1689 
 1690         /*
 1691          * IGMPv1/v2/v3 host report and state-change timer processing.
 1692          * Note: Processing a v3 group timer may remove a node.
 1693          */
 1694         LIST_FOREACH(igi, &V_igi_head, igi_link) {
 1695                 ifp = igi->igi_ifp;
 1696 
 1697                 if (igi->igi_version == IGMP_VERSION_3) {
 1698                         loop = (igi->igi_flags & IGIF_LOOPBACK) ? 1 : 0;
 1699                         uri_fasthz = IGMP_RANDOM_DELAY(igi->igi_uri *
 1700                             PR_FASTHZ);
 1701 
 1702                         memset(&qrq, 0, sizeof(struct ifqueue));
 1703                         IFQ_SET_MAXLEN(&qrq, IGMP_MAX_G_GS_PACKETS);
 1704 
 1705                         memset(&scq, 0, sizeof(struct ifqueue));
 1706                         IFQ_SET_MAXLEN(&scq, IGMP_MAX_STATE_CHANGE_PACKETS);
 1707                 }
 1708 
 1709                 IF_ADDR_RLOCK(ifp);
 1710                 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
 1711                         if (ifma->ifma_addr->sa_family != AF_INET ||
 1712                             ifma->ifma_protospec == NULL)
 1713                                 continue;
 1714                         inm = (struct in_multi *)ifma->ifma_protospec;
 1715                         switch (igi->igi_version) {
 1716                         case IGMP_VERSION_1:
 1717                         case IGMP_VERSION_2:
 1718                                 igmp_v1v2_process_group_timer(inm,
 1719                                     igi->igi_version);
 1720                                 break;
 1721                         case IGMP_VERSION_3:
 1722                                 igmp_v3_process_group_timers(igi, &qrq,
 1723                                     &scq, inm, uri_fasthz);
 1724                                 break;
 1725                         }
 1726                 }
 1727                 IF_ADDR_RUNLOCK(ifp);
 1728 
 1729                 if (igi->igi_version == IGMP_VERSION_3) {
 1730                         struct in_multi         *tinm;
 1731 
 1732                         igmp_dispatch_queue(&qrq, 0, loop);
 1733                         igmp_dispatch_queue(&scq, 0, loop);
 1734 
 1735                         /*
 1736                          * Free the in_multi reference(s) for this
 1737                          * IGMP lifecycle.
 1738                          */
 1739                         SLIST_FOREACH_SAFE(inm, &igi->igi_relinmhead,
 1740                             inm_nrele, tinm) {
 1741                                 SLIST_REMOVE_HEAD(&igi->igi_relinmhead,
 1742                                     inm_nrele);
 1743                                 inm_release_locked(inm);
 1744                         }
 1745                 }
 1746         }
 1747 
 1748 out_locked:
 1749         IGMP_UNLOCK();
 1750         IN_MULTI_UNLOCK();
 1751 }
 1752 
 1753 /*
 1754  * Update host report group timer for IGMPv1/v2.
 1755  * Will update the global pending timer flags.
 1756  */
 1757 static void
 1758 igmp_v1v2_process_group_timer(struct in_multi *inm, const int version)
 1759 {
 1760         int report_timer_expired;
 1761 
 1762         IN_MULTI_LOCK_ASSERT();
 1763         IGMP_LOCK_ASSERT();
 1764 
 1765         if (inm->inm_timer == 0) {
 1766                 report_timer_expired = 0;
 1767         } else if (--inm->inm_timer == 0) {
 1768                 report_timer_expired = 1;
 1769         } else {
 1770                 V_current_state_timers_running = 1;
 1771                 return;
 1772         }
 1773 
 1774         switch (inm->inm_state) {
 1775         case IGMP_NOT_MEMBER:
 1776         case IGMP_SILENT_MEMBER:
 1777         case IGMP_IDLE_MEMBER:
 1778         case IGMP_LAZY_MEMBER:
 1779         case IGMP_SLEEPING_MEMBER:
 1780         case IGMP_AWAKENING_MEMBER:
 1781                 break;
 1782         case IGMP_REPORTING_MEMBER:
 1783                 if (report_timer_expired) {
 1784                         inm->inm_state = IGMP_IDLE_MEMBER;
 1785                         (void)igmp_v1v2_queue_report(inm,
 1786                             (version == IGMP_VERSION_2) ?
 1787                              IGMP_v2_HOST_MEMBERSHIP_REPORT :
 1788                              IGMP_v1_HOST_MEMBERSHIP_REPORT);
 1789                 }
 1790                 break;
 1791         case IGMP_G_QUERY_PENDING_MEMBER:
 1792         case IGMP_SG_QUERY_PENDING_MEMBER:
 1793         case IGMP_LEAVING_MEMBER:
 1794                 break;
 1795         }
 1796 }
 1797 
 1798 /*
 1799  * Update a group's timers for IGMPv3.
 1800  * Will update the global pending timer flags.
 1801  * Note: Unlocked read from igi.
 1802  */
 1803 static void
 1804 igmp_v3_process_group_timers(struct igmp_ifinfo *igi,
 1805     struct ifqueue *qrq, struct ifqueue *scq,
 1806     struct in_multi *inm, const int uri_fasthz)
 1807 {
 1808         int query_response_timer_expired;
 1809         int state_change_retransmit_timer_expired;
 1810 
 1811         IN_MULTI_LOCK_ASSERT();
 1812         IGMP_LOCK_ASSERT();
 1813 
 1814         query_response_timer_expired = 0;
 1815         state_change_retransmit_timer_expired = 0;
 1816 
 1817         /*
 1818          * During a transition from v1/v2 compatibility mode back to v3,
 1819          * a group record in REPORTING state may still have its group
 1820          * timer active. This is a no-op in this function; it is easier
 1821          * to deal with it here than to complicate the slow-timeout path.
 1822          */
 1823         if (inm->inm_timer == 0) {
 1824                 query_response_timer_expired = 0;
 1825         } else if (--inm->inm_timer == 0) {
 1826                 query_response_timer_expired = 1;
 1827         } else {
 1828                 V_current_state_timers_running = 1;
 1829         }
 1830 
 1831         if (inm->inm_sctimer == 0) {
 1832                 state_change_retransmit_timer_expired = 0;
 1833         } else if (--inm->inm_sctimer == 0) {
 1834                 state_change_retransmit_timer_expired = 1;
 1835         } else {
 1836                 V_state_change_timers_running = 1;
 1837         }
 1838 
 1839         /* We are in fasttimo, so be quick about it. */
 1840         if (!state_change_retransmit_timer_expired &&
 1841             !query_response_timer_expired)
 1842                 return;
 1843 
 1844         switch (inm->inm_state) {
 1845         case IGMP_NOT_MEMBER:
 1846         case IGMP_SILENT_MEMBER:
 1847         case IGMP_SLEEPING_MEMBER:
 1848         case IGMP_LAZY_MEMBER:
 1849         case IGMP_AWAKENING_MEMBER:
 1850         case IGMP_IDLE_MEMBER:
 1851                 break;
 1852         case IGMP_G_QUERY_PENDING_MEMBER:
 1853         case IGMP_SG_QUERY_PENDING_MEMBER:
 1854                 /*
 1855                  * Respond to a previously pending Group-Specific
 1856                  * or Group-and-Source-Specific query by enqueueing
 1857                  * the appropriate Current-State report for
 1858                  * immediate transmission.
 1859                  */
 1860                 if (query_response_timer_expired) {
 1861                         int retval;
 1862 
 1863                         retval = igmp_v3_enqueue_group_record(qrq, inm, 0, 1,
 1864                             (inm->inm_state == IGMP_SG_QUERY_PENDING_MEMBER));
 1865                         CTR2(KTR_IGMPV3, "%s: enqueue record = %d",
 1866                             __func__, retval);
 1867                         inm->inm_state = IGMP_REPORTING_MEMBER;
 1868                         /* XXX Clear recorded sources for next time. */
 1869                         inm_clear_recorded(inm);
 1870                 }
 1871                 /* FALLTHROUGH */
 1872         case IGMP_REPORTING_MEMBER:
 1873         case IGMP_LEAVING_MEMBER:
 1874                 if (state_change_retransmit_timer_expired) {
 1875                         /*
 1876                          * State-change retransmission timer fired.
 1877                          * If there are any further pending retransmissions,
 1878                          * set the global pending state-change flag, and
 1879                          * reset the timer.
 1880                          */
 1881                         if (--inm->inm_scrv > 0) {
 1882                                 inm->inm_sctimer = uri_fasthz;
 1883                                 V_state_change_timers_running = 1;
 1884                         }
 1885                         /*
 1886                          * Retransmit the previously computed state-change
 1887                          * report. If there are no further pending
 1888                          * retransmissions, the mbuf queue will be consumed.
 1889                          * Update T0 state to T1 as we have now sent
 1890                          * a state-change.
 1891                          */
 1892                         (void)igmp_v3_merge_state_changes(inm, scq);
 1893 
 1894                         inm_commit(inm);
 1895                         CTR3(KTR_IGMPV3, "%s: T1 -> T0 for %s/%s", __func__,
 1896                             inet_ntoa(inm->inm_addr), inm->inm_ifp->if_xname);
 1897 
 1898                         /*
 1899                          * If we are leaving the group for good, make sure
 1900                          * we release IGMP's reference to it.
 1901                          * This release must be deferred using a SLIST,
 1902                          * as we are called from a loop which traverses
 1903                          * the in_ifmultiaddr TAILQ.
 1904                          */
 1905                         if (inm->inm_state == IGMP_LEAVING_MEMBER &&
 1906                             inm->inm_scrv == 0) {
 1907                                 inm->inm_state = IGMP_NOT_MEMBER;
 1908                                 SLIST_INSERT_HEAD(&igi->igi_relinmhead,
 1909                                     inm, inm_nrele);
 1910                         }
 1911                 }
 1912                 break;
 1913         }
 1914 }
 1915 
 1916 
 1917 /*
 1918  * Suppress a group's pending response to a group or source/group query.
 1919  *
 1920  * Do NOT suppress state changes. This leads to IGMPv3 inconsistency.
 1921  * Do NOT update ST1/ST0 as this operation merely suppresses
 1922  * the currently pending group record.
 1923  * Do NOT suppress the response to a general query. It is possible but
 1924  * it would require adding another state or flag.
 1925  */
 1926 static void
 1927 igmp_v3_suppress_group_record(struct in_multi *inm)
 1928 {
 1929 
 1930         IN_MULTI_LOCK_ASSERT();
 1931 
 1932         KASSERT(inm->inm_igi->igi_version == IGMP_VERSION_3,
 1933                 ("%s: not IGMPv3 mode on link", __func__));
 1934 
 1935         if (inm->inm_state != IGMP_G_QUERY_PENDING_MEMBER ||
 1936             inm->inm_state != IGMP_SG_QUERY_PENDING_MEMBER)
 1937                 return;
 1938 
 1939         if (inm->inm_state == IGMP_SG_QUERY_PENDING_MEMBER)
 1940                 inm_clear_recorded(inm);
 1941 
 1942         inm->inm_timer = 0;
 1943         inm->inm_state = IGMP_REPORTING_MEMBER;
 1944 }
 1945 
 1946 /*
 1947  * Switch to a different IGMP version on the given interface,
 1948  * as per Section 7.2.1.
 1949  */
 1950 static void
 1951 igmp_set_version(struct igmp_ifinfo *igi, const int version)
 1952 {
 1953         int old_version_timer;
 1954 
 1955         IGMP_LOCK_ASSERT();
 1956 
 1957         CTR4(KTR_IGMPV3, "%s: switching to v%d on ifp %p(%s)", __func__,
 1958             version, igi->igi_ifp, igi->igi_ifp->if_xname);
 1959 
 1960         if (version == IGMP_VERSION_1 || version == IGMP_VERSION_2) {
 1961                 /*
 1962                  * Compute the "Older Version Querier Present" timer as per
 1963                  * Section 8.12.
 1964                  */
 1965                 old_version_timer = igi->igi_rv * igi->igi_qi + igi->igi_qri;
 1966                 old_version_timer *= PR_SLOWHZ;
 1967 
 1968                 if (version == IGMP_VERSION_1) {
 1969                         igi->igi_v1_timer = old_version_timer;
 1970                         igi->igi_v2_timer = 0;
 1971                 } else if (version == IGMP_VERSION_2) {
 1972                         igi->igi_v1_timer = 0;
 1973                         igi->igi_v2_timer = old_version_timer;
 1974                 }
 1975         }
 1976 
 1977         if (igi->igi_v1_timer == 0 && igi->igi_v2_timer > 0) {
 1978                 if (igi->igi_version != IGMP_VERSION_2) {
 1979                         igi->igi_version = IGMP_VERSION_2;
 1980                         igmp_v3_cancel_link_timers(igi);
 1981                 }
 1982         } else if (igi->igi_v1_timer > 0) {
 1983                 if (igi->igi_version != IGMP_VERSION_1) {
 1984                         igi->igi_version = IGMP_VERSION_1;
 1985                         igmp_v3_cancel_link_timers(igi);
 1986                 }
 1987         }
 1988 }
 1989 
 1990 /*
 1991  * Cancel pending IGMPv3 timers for the given link and all groups
 1992  * joined on it; state-change, general-query, and group-query timers.
 1993  *
 1994  * Only ever called on a transition from v3 to Compatibility mode. Kill
 1995  * the timers stone dead (this may be expensive for large N groups), they
 1996  * will be restarted if Compatibility Mode deems that they must be due to
 1997  * query processing.
 1998  */
 1999 static void
 2000 igmp_v3_cancel_link_timers(struct igmp_ifinfo *igi)
 2001 {
 2002         struct ifmultiaddr      *ifma;
 2003         struct ifnet            *ifp;
 2004         struct in_multi         *inm, *tinm;
 2005 
 2006         CTR3(KTR_IGMPV3, "%s: cancel v3 timers on ifp %p(%s)", __func__,
 2007             igi->igi_ifp, igi->igi_ifp->if_xname);
 2008 
 2009         IN_MULTI_LOCK_ASSERT();
 2010         IGMP_LOCK_ASSERT();
 2011 
 2012         /*
 2013          * Stop the v3 General Query Response on this link stone dead.
 2014          * If fasttimo is woken up due to V_interface_timers_running,
 2015          * the flag will be cleared if there are no pending link timers.
 2016          */
 2017         igi->igi_v3_timer = 0;
 2018 
 2019         /*
 2020          * Now clear the current-state and state-change report timers
 2021          * for all memberships scoped to this link.
 2022          */
 2023         ifp = igi->igi_ifp;
 2024         IF_ADDR_RLOCK(ifp);
 2025         TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
 2026                 if (ifma->ifma_addr->sa_family != AF_INET ||
 2027                     ifma->ifma_protospec == NULL)
 2028                         continue;
 2029                 inm = (struct in_multi *)ifma->ifma_protospec;
 2030                 switch (inm->inm_state) {
 2031                 case IGMP_NOT_MEMBER:
 2032                 case IGMP_SILENT_MEMBER:
 2033                 case IGMP_IDLE_MEMBER:
 2034                 case IGMP_LAZY_MEMBER:
 2035                 case IGMP_SLEEPING_MEMBER:
 2036                 case IGMP_AWAKENING_MEMBER:
 2037                         /*
 2038                          * These states are either not relevant in v3 mode,
 2039                          * or are unreported. Do nothing.
 2040                          */
 2041                         break;
 2042                 case IGMP_LEAVING_MEMBER:
 2043                         /*
 2044                          * If we are leaving the group and switching to
 2045                          * compatibility mode, we need to release the final
 2046                          * reference held for issuing the INCLUDE {}, and
 2047                          * transition to REPORTING to ensure the host leave
 2048                          * message is sent upstream to the old querier --
 2049                          * transition to NOT would lose the leave and race.
 2050                          */
 2051                         SLIST_INSERT_HEAD(&igi->igi_relinmhead, inm, inm_nrele);
 2052                         /* FALLTHROUGH */
 2053                 case IGMP_G_QUERY_PENDING_MEMBER:
 2054                 case IGMP_SG_QUERY_PENDING_MEMBER:
 2055                         inm_clear_recorded(inm);
 2056                         /* FALLTHROUGH */
 2057                 case IGMP_REPORTING_MEMBER:
 2058                         inm->inm_state = IGMP_REPORTING_MEMBER;
 2059                         break;
 2060                 }
 2061                 /*
 2062                  * Always clear state-change and group report timers.
 2063                  * Free any pending IGMPv3 state-change records.
 2064                  */
 2065                 inm->inm_sctimer = 0;
 2066                 inm->inm_timer = 0;
 2067                 _IF_DRAIN(&inm->inm_scq);
 2068         }
 2069         IF_ADDR_RUNLOCK(ifp);
 2070         SLIST_FOREACH_SAFE(inm, &igi->igi_relinmhead, inm_nrele, tinm) {
 2071                 SLIST_REMOVE_HEAD(&igi->igi_relinmhead, inm_nrele);
 2072                 inm_release_locked(inm);
 2073         }
 2074 }
 2075 
 2076 /*
 2077  * Update the Older Version Querier Present timers for a link.
 2078  * See Section 7.2.1 of RFC 3376.
 2079  */
 2080 static void
 2081 igmp_v1v2_process_querier_timers(struct igmp_ifinfo *igi)
 2082 {
 2083 
 2084         IGMP_LOCK_ASSERT();
 2085 
 2086         if (igi->igi_v1_timer == 0 && igi->igi_v2_timer == 0) {
 2087                 /*
 2088                  * IGMPv1 and IGMPv2 Querier Present timers expired.
 2089                  *
 2090                  * Revert to IGMPv3.
 2091                  */
 2092                 if (igi->igi_version != IGMP_VERSION_3) {
 2093                         CTR5(KTR_IGMPV3,
 2094                             "%s: transition from v%d -> v%d on %p(%s)",
 2095                             __func__, igi->igi_version, IGMP_VERSION_3,
 2096                             igi->igi_ifp, igi->igi_ifp->if_xname);
 2097                         igi->igi_version = IGMP_VERSION_3;
 2098                 }
 2099         } else if (igi->igi_v1_timer == 0 && igi->igi_v2_timer > 0) {
 2100                 /*
 2101                  * IGMPv1 Querier Present timer expired,
 2102                  * IGMPv2 Querier Present timer running.
 2103                  * If IGMPv2 was disabled since last timeout,
 2104                  * revert to IGMPv3.
 2105                  * If IGMPv2 is enabled, revert to IGMPv2.
 2106                  */
 2107                 if (!V_igmp_v2enable) {
 2108                         CTR5(KTR_IGMPV3,
 2109                             "%s: transition from v%d -> v%d on %p(%s)",
 2110                             __func__, igi->igi_version, IGMP_VERSION_3,
 2111                             igi->igi_ifp, igi->igi_ifp->if_xname);
 2112                         igi->igi_v2_timer = 0;
 2113                         igi->igi_version = IGMP_VERSION_3;
 2114                 } else {
 2115                         --igi->igi_v2_timer;
 2116                         if (igi->igi_version != IGMP_VERSION_2) {
 2117                                 CTR5(KTR_IGMPV3,
 2118                                     "%s: transition from v%d -> v%d on %p(%s)",
 2119                                     __func__, igi->igi_version, IGMP_VERSION_2,
 2120                                     igi->igi_ifp, igi->igi_ifp->if_xname);
 2121                                 igi->igi_version = IGMP_VERSION_2;
 2122                         }
 2123                 }
 2124         } else if (igi->igi_v1_timer > 0) {
 2125                 /*
 2126                  * IGMPv1 Querier Present timer running.
 2127                  * Stop IGMPv2 timer if running.
 2128                  *
 2129                  * If IGMPv1 was disabled since last timeout,
 2130                  * revert to IGMPv3.
 2131                  * If IGMPv1 is enabled, reset IGMPv2 timer if running.
 2132                  */
 2133                 if (!V_igmp_v1enable) {
 2134                         CTR5(KTR_IGMPV3,
 2135                             "%s: transition from v%d -> v%d on %p(%s)",
 2136                             __func__, igi->igi_version, IGMP_VERSION_3,
 2137                             igi->igi_ifp, igi->igi_ifp->if_xname);
 2138                         igi->igi_v1_timer = 0;
 2139                         igi->igi_version = IGMP_VERSION_3;
 2140                 } else {
 2141                         --igi->igi_v1_timer;
 2142                 }
 2143                 if (igi->igi_v2_timer > 0) {
 2144                         CTR3(KTR_IGMPV3,
 2145                             "%s: cancel v2 timer on %p(%s)",
 2146                             __func__, igi->igi_ifp, igi->igi_ifp->if_xname);
 2147                         igi->igi_v2_timer = 0;
 2148                 }
 2149         }
 2150 }
 2151 
 2152 /*
 2153  * Global slowtimo handler.
 2154  * VIMAGE: Timeout handlers are expected to service all vimages.
 2155  */
 2156 void
 2157 igmp_slowtimo(void)
 2158 {
 2159         VNET_ITERATOR_DECL(vnet_iter);
 2160 
 2161         VNET_LIST_RLOCK_NOSLEEP();
 2162         VNET_FOREACH(vnet_iter) {
 2163                 CURVNET_SET(vnet_iter);
 2164                 igmp_slowtimo_vnet();
 2165                 CURVNET_RESTORE();
 2166         }
 2167         VNET_LIST_RUNLOCK_NOSLEEP();
 2168 }
 2169 
 2170 /*
 2171  * Per-vnet slowtimo handler.
 2172  */
 2173 static void
 2174 igmp_slowtimo_vnet(void)
 2175 {
 2176         struct igmp_ifinfo *igi;
 2177 
 2178         IGMP_LOCK();
 2179 
 2180         LIST_FOREACH(igi, &V_igi_head, igi_link) {
 2181                 igmp_v1v2_process_querier_timers(igi);
 2182         }
 2183 
 2184         IGMP_UNLOCK();
 2185 }
 2186 
 2187 /*
 2188  * Dispatch an IGMPv1/v2 host report or leave message.
 2189  * These are always small enough to fit inside a single mbuf.
 2190  */
 2191 static int
 2192 igmp_v1v2_queue_report(struct in_multi *inm, const int type)
 2193 {
 2194         struct ifnet            *ifp;
 2195         struct igmp             *igmp;
 2196         struct ip               *ip;
 2197         struct mbuf             *m;
 2198 
 2199         IN_MULTI_LOCK_ASSERT();
 2200         IGMP_LOCK_ASSERT();
 2201 
 2202         ifp = inm->inm_ifp;
 2203 
 2204         MGETHDR(m, M_DONTWAIT, MT_DATA);
 2205         if (m == NULL)
 2206                 return (ENOMEM);
 2207         MH_ALIGN(m, sizeof(struct ip) + sizeof(struct igmp));
 2208 
 2209         m->m_pkthdr.len = sizeof(struct ip) + sizeof(struct igmp);
 2210 
 2211         m->m_data += sizeof(struct ip);
 2212         m->m_len = sizeof(struct igmp);
 2213 
 2214         igmp = mtod(m, struct igmp *);
 2215         igmp->igmp_type = type;
 2216         igmp->igmp_code = 0;
 2217         igmp->igmp_group = inm->inm_addr;
 2218         igmp->igmp_cksum = 0;
 2219         igmp->igmp_cksum = in_cksum(m, sizeof(struct igmp));
 2220 
 2221         m->m_data -= sizeof(struct ip);
 2222         m->m_len += sizeof(struct ip);
 2223 
 2224         ip = mtod(m, struct ip *);
 2225         ip->ip_tos = 0;
 2226         ip->ip_len = sizeof(struct ip) + sizeof(struct igmp);
 2227         ip->ip_off = 0;
 2228         ip->ip_p = IPPROTO_IGMP;
 2229         ip->ip_src.s_addr = INADDR_ANY;
 2230 
 2231         if (type == IGMP_HOST_LEAVE_MESSAGE)
 2232                 ip->ip_dst.s_addr = htonl(INADDR_ALLRTRS_GROUP);
 2233         else
 2234                 ip->ip_dst = inm->inm_addr;
 2235 
 2236         igmp_save_context(m, ifp);
 2237 
 2238         m->m_flags |= M_IGMPV2;
 2239         if (inm->inm_igi->igi_flags & IGIF_LOOPBACK)
 2240                 m->m_flags |= M_IGMP_LOOP;
 2241 
 2242         CTR2(KTR_IGMPV3, "%s: netisr_dispatch(NETISR_IGMP, %p)", __func__, m);
 2243         netisr_dispatch(NETISR_IGMP, m);
 2244 
 2245         return (0);
 2246 }
 2247 
 2248 /*
 2249  * Process a state change from the upper layer for the given IPv4 group.
 2250  *
 2251  * Each socket holds a reference on the in_multi in its own ip_moptions.
 2252  * The socket layer will have made the necessary updates to.the group
 2253  * state, it is now up to IGMP to issue a state change report if there
 2254  * has been any change between T0 (when the last state-change was issued)
 2255  * and T1 (now).
 2256  *
 2257  * We use the IGMPv3 state machine at group level. The IGMP module
 2258  * however makes the decision as to which IGMP protocol version to speak.
 2259  * A state change *from* INCLUDE {} always means an initial join.
 2260  * A state change *to* INCLUDE {} always means a final leave.
 2261  *
 2262  * FUTURE: If IGIF_V3LITE is enabled for this interface, then we can
 2263  * save ourselves a bunch of work; any exclusive mode groups need not
 2264  * compute source filter lists.
 2265  *
 2266  * VIMAGE: curvnet should have been set by caller, as this routine
 2267  * is called from the socket option handlers.
 2268  */
 2269 int
 2270 igmp_change_state(struct in_multi *inm)
 2271 {
 2272         struct igmp_ifinfo *igi;
 2273         struct ifnet *ifp;
 2274         int error;
 2275 
 2276         IN_MULTI_LOCK_ASSERT();
 2277 
 2278         error = 0;
 2279 
 2280         /*
 2281          * Try to detect if the upper layer just asked us to change state
 2282          * for an interface which has now gone away.
 2283          */
 2284         KASSERT(inm->inm_ifma != NULL, ("%s: no ifma", __func__));
 2285         ifp = inm->inm_ifma->ifma_ifp;
 2286         /*
 2287          * Sanity check that netinet's notion of ifp is the
 2288          * same as net's.
 2289          */
 2290         KASSERT(inm->inm_ifp == ifp, ("%s: bad ifp", __func__));
 2291 
 2292         IGMP_LOCK();
 2293 
 2294         igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
 2295         KASSERT(igi != NULL, ("%s: no igmp_ifinfo for ifp %p", __func__, ifp));
 2296 
 2297         /*
 2298          * If we detect a state transition to or from MCAST_UNDEFINED
 2299          * for this group, then we are starting or finishing an IGMP
 2300          * life cycle for this group.
 2301          */
 2302         if (inm->inm_st[1].iss_fmode != inm->inm_st[0].iss_fmode) {
 2303                 CTR3(KTR_IGMPV3, "%s: inm transition %d -> %d", __func__,
 2304                     inm->inm_st[0].iss_fmode, inm->inm_st[1].iss_fmode);
 2305                 if (inm->inm_st[0].iss_fmode == MCAST_UNDEFINED) {
 2306                         CTR1(KTR_IGMPV3, "%s: initial join", __func__);
 2307                         error = igmp_initial_join(inm, igi);
 2308                         goto out_locked;
 2309                 } else if (inm->inm_st[1].iss_fmode == MCAST_UNDEFINED) {
 2310                         CTR1(KTR_IGMPV3, "%s: final leave", __func__);
 2311                         igmp_final_leave(inm, igi);
 2312                         goto out_locked;
 2313                 }
 2314         } else {
 2315                 CTR1(KTR_IGMPV3, "%s: filter set change", __func__);
 2316         }
 2317 
 2318         error = igmp_handle_state_change(inm, igi);
 2319 
 2320 out_locked:
 2321         IGMP_UNLOCK();
 2322         return (error);
 2323 }
 2324 
 2325 /*
 2326  * Perform the initial join for an IGMP group.
 2327  *
 2328  * When joining a group:
 2329  *  If the group should have its IGMP traffic suppressed, do nothing.
 2330  *  IGMPv1 starts sending IGMPv1 host membership reports.
 2331  *  IGMPv2 starts sending IGMPv2 host membership reports.
 2332  *  IGMPv3 will schedule an IGMPv3 state-change report containing the
 2333  *  initial state of the membership.
 2334  */
 2335 static int
 2336 igmp_initial_join(struct in_multi *inm, struct igmp_ifinfo *igi)
 2337 {
 2338         struct ifnet            *ifp;
 2339         struct ifqueue          *ifq;
 2340         int                      error, retval, syncstates;
 2341 
 2342         CTR4(KTR_IGMPV3, "%s: initial join %s on ifp %p(%s)",
 2343             __func__, inet_ntoa(inm->inm_addr), inm->inm_ifp,
 2344             inm->inm_ifp->if_xname);
 2345 
 2346         error = 0;
 2347         syncstates = 1;
 2348 
 2349         ifp = inm->inm_ifp;
 2350 
 2351         IN_MULTI_LOCK_ASSERT();
 2352         IGMP_LOCK_ASSERT();
 2353 
 2354         KASSERT(igi && igi->igi_ifp == ifp, ("%s: inconsistent ifp", __func__));
 2355 
 2356         /*
 2357          * Groups joined on loopback or marked as 'not reported',
 2358          * e.g. 224.0.0.1, enter the IGMP_SILENT_MEMBER state and
 2359          * are never reported in any IGMP protocol exchanges.
 2360          * All other groups enter the appropriate IGMP state machine
 2361          * for the version in use on this link.
 2362          * A link marked as IGIF_SILENT causes IGMP to be completely
 2363          * disabled for the link.
 2364          */
 2365         if ((ifp->if_flags & IFF_LOOPBACK) ||
 2366             (igi->igi_flags & IGIF_SILENT) ||
 2367             !igmp_isgroupreported(inm->inm_addr)) {
 2368                 CTR1(KTR_IGMPV3,
 2369 "%s: not kicking state machine for silent group", __func__);
 2370                 inm->inm_state = IGMP_SILENT_MEMBER;
 2371                 inm->inm_timer = 0;
 2372         } else {
 2373                 /*
 2374                  * Deal with overlapping in_multi lifecycle.
 2375                  * If this group was LEAVING, then make sure
 2376                  * we drop the reference we picked up to keep the
 2377                  * group around for the final INCLUDE {} enqueue.
 2378                  */
 2379                 if (igi->igi_version == IGMP_VERSION_3 &&
 2380                     inm->inm_state == IGMP_LEAVING_MEMBER)
 2381                         inm_release_locked(inm);
 2382 
 2383                 inm->inm_state = IGMP_REPORTING_MEMBER;
 2384 
 2385                 switch (igi->igi_version) {
 2386                 case IGMP_VERSION_1:
 2387                 case IGMP_VERSION_2:
 2388                         inm->inm_state = IGMP_IDLE_MEMBER;
 2389                         error = igmp_v1v2_queue_report(inm,
 2390                             (igi->igi_version == IGMP_VERSION_2) ?
 2391                              IGMP_v2_HOST_MEMBERSHIP_REPORT :
 2392                              IGMP_v1_HOST_MEMBERSHIP_REPORT);
 2393                         if (error == 0) {
 2394                                 inm->inm_timer = IGMP_RANDOM_DELAY(
 2395                                     IGMP_V1V2_MAX_RI * PR_FASTHZ);
 2396                                 V_current_state_timers_running = 1;
 2397                         }
 2398                         break;
 2399 
 2400                 case IGMP_VERSION_3:
 2401                         /*
 2402                          * Defer update of T0 to T1, until the first copy
 2403                          * of the state change has been transmitted.
 2404                          */
 2405                         syncstates = 0;
 2406 
 2407                         /*
 2408                          * Immediately enqueue a State-Change Report for
 2409                          * this interface, freeing any previous reports.
 2410                          * Don't kick the timers if there is nothing to do,
 2411                          * or if an error occurred.
 2412                          */
 2413                         ifq = &inm->inm_scq;
 2414                         _IF_DRAIN(ifq);
 2415                         retval = igmp_v3_enqueue_group_record(ifq, inm, 1,
 2416                             0, 0);
 2417                         CTR2(KTR_IGMPV3, "%s: enqueue record = %d",
 2418                             __func__, retval);
 2419                         if (retval <= 0) {
 2420                                 error = retval * -1;
 2421                                 break;
 2422                         }
 2423 
 2424                         /*
 2425                          * Schedule transmission of pending state-change
 2426                          * report up to RV times for this link. The timer
 2427                          * will fire at the next igmp_fasttimo (~200ms),
 2428                          * giving us an opportunity to merge the reports.
 2429                          */
 2430                         if (igi->igi_flags & IGIF_LOOPBACK) {
 2431                                 inm->inm_scrv = 1;
 2432                         } else {
 2433                                 KASSERT(igi->igi_rv > 1,
 2434                                    ("%s: invalid robustness %d", __func__,
 2435                                     igi->igi_rv));
 2436                                 inm->inm_scrv = igi->igi_rv;
 2437                         }
 2438                         inm->inm_sctimer = 1;
 2439                         V_state_change_timers_running = 1;
 2440 
 2441                         error = 0;
 2442                         break;
 2443                 }
 2444         }
 2445 
 2446         /*
 2447          * Only update the T0 state if state change is atomic,
 2448          * i.e. we don't need to wait for a timer to fire before we
 2449          * can consider the state change to have been communicated.
 2450          */
 2451         if (syncstates) {
 2452                 inm_commit(inm);
 2453                 CTR3(KTR_IGMPV3, "%s: T1 -> T0 for %s/%s", __func__,
 2454                     inet_ntoa(inm->inm_addr), inm->inm_ifp->if_xname);
 2455         }
 2456 
 2457         return (error);
 2458 }
 2459 
 2460 /*
 2461  * Issue an intermediate state change during the IGMP life-cycle.
 2462  */
 2463 static int
 2464 igmp_handle_state_change(struct in_multi *inm, struct igmp_ifinfo *igi)
 2465 {
 2466         struct ifnet            *ifp;
 2467         int                      retval;
 2468 
 2469         CTR4(KTR_IGMPV3, "%s: state change for %s on ifp %p(%s)",
 2470             __func__, inet_ntoa(inm->inm_addr), inm->inm_ifp,
 2471             inm->inm_ifp->if_xname);
 2472 
 2473         ifp = inm->inm_ifp;
 2474 
 2475         IN_MULTI_LOCK_ASSERT();
 2476         IGMP_LOCK_ASSERT();
 2477 
 2478         KASSERT(igi && igi->igi_ifp == ifp, ("%s: inconsistent ifp", __func__));
 2479 
 2480         if ((ifp->if_flags & IFF_LOOPBACK) ||
 2481             (igi->igi_flags & IGIF_SILENT) ||
 2482             !igmp_isgroupreported(inm->inm_addr) ||
 2483             (igi->igi_version != IGMP_VERSION_3)) {
 2484                 if (!igmp_isgroupreported(inm->inm_addr)) {
 2485                         CTR1(KTR_IGMPV3,
 2486 "%s: not kicking state machine for silent group", __func__);
 2487                 }
 2488                 CTR1(KTR_IGMPV3, "%s: nothing to do", __func__);
 2489                 inm_commit(inm);
 2490                 CTR3(KTR_IGMPV3, "%s: T1 -> T0 for %s/%s", __func__,
 2491                     inet_ntoa(inm->inm_addr), inm->inm_ifp->if_xname);
 2492                 return (0);
 2493         }
 2494 
 2495         _IF_DRAIN(&inm->inm_scq);
 2496 
 2497         retval = igmp_v3_enqueue_group_record(&inm->inm_scq, inm, 1, 0, 0);
 2498         CTR2(KTR_IGMPV3, "%s: enqueue record = %d", __func__, retval);
 2499         if (retval <= 0)
 2500                 return (-retval);
 2501 
 2502         /*
 2503          * If record(s) were enqueued, start the state-change
 2504          * report timer for this group.
 2505          */
 2506         inm->inm_scrv = ((igi->igi_flags & IGIF_LOOPBACK) ? 1 : igi->igi_rv);
 2507         inm->inm_sctimer = 1;
 2508         V_state_change_timers_running = 1;
 2509 
 2510         return (0);
 2511 }
 2512 
 2513 /*
 2514  * Perform the final leave for an IGMP group.
 2515  *
 2516  * When leaving a group:
 2517  *  IGMPv1 does nothing.
 2518  *  IGMPv2 sends a host leave message, if and only if we are the reporter.
 2519  *  IGMPv3 enqueues a state-change report containing a transition
 2520  *  to INCLUDE {} for immediate transmission.
 2521  */
 2522 static void
 2523 igmp_final_leave(struct in_multi *inm, struct igmp_ifinfo *igi)
 2524 {
 2525         int syncstates;
 2526 
 2527         syncstates = 1;
 2528 
 2529         CTR4(KTR_IGMPV3, "%s: final leave %s on ifp %p(%s)",
 2530             __func__, inet_ntoa(inm->inm_addr), inm->inm_ifp,
 2531             inm->inm_ifp->if_xname);
 2532 
 2533         IN_MULTI_LOCK_ASSERT();
 2534         IGMP_LOCK_ASSERT();
 2535 
 2536         switch (inm->inm_state) {
 2537         case IGMP_NOT_MEMBER:
 2538         case IGMP_SILENT_MEMBER:
 2539         case IGMP_LEAVING_MEMBER:
 2540                 /* Already leaving or left; do nothing. */
 2541                 CTR1(KTR_IGMPV3,
 2542 "%s: not kicking state machine for silent group", __func__);
 2543                 break;
 2544         case IGMP_REPORTING_MEMBER:
 2545         case IGMP_IDLE_MEMBER:
 2546         case IGMP_G_QUERY_PENDING_MEMBER:
 2547         case IGMP_SG_QUERY_PENDING_MEMBER:
 2548                 if (igi->igi_version == IGMP_VERSION_2) {
 2549 #ifdef INVARIANTS
 2550                         if (inm->inm_state == IGMP_G_QUERY_PENDING_MEMBER ||
 2551                             inm->inm_state == IGMP_SG_QUERY_PENDING_MEMBER)
 2552                         panic("%s: IGMPv3 state reached, not IGMPv3 mode",
 2553                              __func__);
 2554 #endif
 2555                         igmp_v1v2_queue_report(inm, IGMP_HOST_LEAVE_MESSAGE);
 2556                         inm->inm_state = IGMP_NOT_MEMBER;
 2557                 } else if (igi->igi_version == IGMP_VERSION_3) {
 2558                         /*
 2559                          * Stop group timer and all pending reports.
 2560                          * Immediately enqueue a state-change report
 2561                          * TO_IN {} to be sent on the next fast timeout,
 2562                          * giving us an opportunity to merge reports.
 2563                          */
 2564                         _IF_DRAIN(&inm->inm_scq);
 2565                         inm->inm_timer = 0;
 2566                         if (igi->igi_flags & IGIF_LOOPBACK) {
 2567                                 inm->inm_scrv = 1;
 2568                         } else {
 2569                                 inm->inm_scrv = igi->igi_rv;
 2570                         }
 2571                         CTR4(KTR_IGMPV3, "%s: Leaving %s/%s with %d "
 2572                             "pending retransmissions.", __func__,
 2573                             inet_ntoa(inm->inm_addr),
 2574                             inm->inm_ifp->if_xname, inm->inm_scrv);
 2575                         if (inm->inm_scrv == 0) {
 2576                                 inm->inm_state = IGMP_NOT_MEMBER;
 2577                                 inm->inm_sctimer = 0;
 2578                         } else {
 2579                                 int retval;
 2580 
 2581                                 inm_acquire_locked(inm);
 2582 
 2583                                 retval = igmp_v3_enqueue_group_record(
 2584                                     &inm->inm_scq, inm, 1, 0, 0);
 2585                                 KASSERT(retval != 0,
 2586                                     ("%s: enqueue record = %d", __func__,
 2587                                      retval));
 2588 
 2589                                 inm->inm_state = IGMP_LEAVING_MEMBER;
 2590                                 inm->inm_sctimer = 1;
 2591                                 V_state_change_timers_running = 1;
 2592                                 syncstates = 0;
 2593                         }
 2594                         break;
 2595                 }
 2596                 break;
 2597         case IGMP_LAZY_MEMBER:
 2598         case IGMP_SLEEPING_MEMBER:
 2599         case IGMP_AWAKENING_MEMBER:
 2600                 /* Our reports are suppressed; do nothing. */
 2601                 break;
 2602         }
 2603 
 2604         if (syncstates) {
 2605                 inm_commit(inm);
 2606                 CTR3(KTR_IGMPV3, "%s: T1 -> T0 for %s/%s", __func__,
 2607                     inet_ntoa(inm->inm_addr), inm->inm_ifp->if_xname);
 2608                 inm->inm_st[1].iss_fmode = MCAST_UNDEFINED;
 2609                 CTR3(KTR_IGMPV3, "%s: T1 now MCAST_UNDEFINED for %s/%s",
 2610                     __func__, inet_ntoa(inm->inm_addr), inm->inm_ifp->if_xname);
 2611         }
 2612 }
 2613 
 2614 /*
 2615  * Enqueue an IGMPv3 group record to the given output queue.
 2616  *
 2617  * XXX This function could do with having the allocation code
 2618  * split out, and the multiple-tree-walks coalesced into a single
 2619  * routine as has been done in igmp_v3_enqueue_filter_change().
 2620  *
 2621  * If is_state_change is zero, a current-state record is appended.
 2622  * If is_state_change is non-zero, a state-change report is appended.
 2623  *
 2624  * If is_group_query is non-zero, an mbuf packet chain is allocated.
 2625  * If is_group_query is zero, and if there is a packet with free space
 2626  * at the tail of the queue, it will be appended to providing there
 2627  * is enough free space.
 2628  * Otherwise a new mbuf packet chain is allocated.
 2629  *
 2630  * If is_source_query is non-zero, each source is checked to see if
 2631  * it was recorded for a Group-Source query, and will be omitted if
 2632  * it is not both in-mode and recorded.
 2633  *
 2634  * The function will attempt to allocate leading space in the packet
 2635  * for the IP/IGMP header to be prepended without fragmenting the chain.
 2636  *
 2637  * If successful the size of all data appended to the queue is returned,
 2638  * otherwise an error code less than zero is returned, or zero if
 2639  * no record(s) were appended.
 2640  */
 2641 static int
 2642 igmp_v3_enqueue_group_record(struct ifqueue *ifq, struct in_multi *inm,
 2643     const int is_state_change, const int is_group_query,
 2644     const int is_source_query)
 2645 {
 2646         struct igmp_grouprec     ig;
 2647         struct igmp_grouprec    *pig;
 2648         struct ifnet            *ifp;
 2649         struct ip_msource       *ims, *nims;
 2650         struct mbuf             *m0, *m, *md;
 2651         int                      error, is_filter_list_change;
 2652         int                      minrec0len, m0srcs, msrcs, nbytes, off;
 2653         int                      record_has_sources;
 2654         int                      now;
 2655         int                      type;
 2656         in_addr_t                naddr;
 2657         uint8_t                  mode;
 2658 
 2659         IN_MULTI_LOCK_ASSERT();
 2660 
 2661         error = 0;
 2662         ifp = inm->inm_ifp;
 2663         is_filter_list_change = 0;
 2664         m = NULL;
 2665         m0 = NULL;
 2666         m0srcs = 0;
 2667         msrcs = 0;
 2668         nbytes = 0;
 2669         nims = NULL;
 2670         record_has_sources = 1;
 2671         pig = NULL;
 2672         type = IGMP_DO_NOTHING;
 2673         mode = inm->inm_st[1].iss_fmode;
 2674 
 2675         /*
 2676          * If we did not transition out of ASM mode during t0->t1,
 2677          * and there are no source nodes to process, we can skip
 2678          * the generation of source records.
 2679          */
 2680         if (inm->inm_st[0].iss_asm > 0 && inm->inm_st[1].iss_asm > 0 &&
 2681             inm->inm_nsrc == 0)
 2682                 record_has_sources = 0;
 2683 
 2684         if (is_state_change) {
 2685                 /*
 2686                  * Queue a state change record.
 2687                  * If the mode did not change, and there are non-ASM
 2688                  * listeners or source filters present,
 2689                  * we potentially need to issue two records for the group.
 2690                  * If we are transitioning to MCAST_UNDEFINED, we need
 2691                  * not send any sources.
 2692                  * If there are ASM listeners, and there was no filter
 2693                  * mode transition of any kind, do nothing.
 2694                  */
 2695                 if (mode != inm->inm_st[0].iss_fmode) {
 2696                         if (mode == MCAST_EXCLUDE) {
 2697                                 CTR1(KTR_IGMPV3, "%s: change to EXCLUDE",
 2698                                     __func__);
 2699                                 type = IGMP_CHANGE_TO_EXCLUDE_MODE;
 2700                         } else {
 2701                                 CTR1(KTR_IGMPV3, "%s: change to INCLUDE",
 2702                                     __func__);
 2703                                 type = IGMP_CHANGE_TO_INCLUDE_MODE;
 2704                                 if (mode == MCAST_UNDEFINED)
 2705                                         record_has_sources = 0;
 2706                         }
 2707                 } else {
 2708                         if (record_has_sources) {
 2709                                 is_filter_list_change = 1;
 2710                         } else {
 2711                                 type = IGMP_DO_NOTHING;
 2712                         }
 2713                 }
 2714         } else {
 2715                 /*
 2716                  * Queue a current state record.
 2717                  */
 2718                 if (mode == MCAST_EXCLUDE) {
 2719                         type = IGMP_MODE_IS_EXCLUDE;
 2720                 } else if (mode == MCAST_INCLUDE) {
 2721                         type = IGMP_MODE_IS_INCLUDE;
 2722                         KASSERT(inm->inm_st[1].iss_asm == 0,
 2723                             ("%s: inm %p is INCLUDE but ASM count is %d",
 2724                              __func__, inm, inm->inm_st[1].iss_asm));
 2725                 }
 2726         }
 2727 
 2728         /*
 2729          * Generate the filter list changes using a separate function.
 2730          */
 2731         if (is_filter_list_change)
 2732                 return (igmp_v3_enqueue_filter_change(ifq, inm));
 2733 
 2734         if (type == IGMP_DO_NOTHING) {
 2735                 CTR3(KTR_IGMPV3, "%s: nothing to do for %s/%s",
 2736                     __func__, inet_ntoa(inm->inm_addr),
 2737                     inm->inm_ifp->if_xname);
 2738                 return (0);
 2739         }
 2740 
 2741         /*
 2742          * If any sources are present, we must be able to fit at least
 2743          * one in the trailing space of the tail packet's mbuf,
 2744          * ideally more.
 2745          */
 2746         minrec0len = sizeof(struct igmp_grouprec);
 2747         if (record_has_sources)
 2748                 minrec0len += sizeof(in_addr_t);
 2749 
 2750         CTR4(KTR_IGMPV3, "%s: queueing %s for %s/%s", __func__,
 2751             igmp_rec_type_to_str(type), inet_ntoa(inm->inm_addr),
 2752             inm->inm_ifp->if_xname);
 2753 
 2754         /*
 2755          * Check if we have a packet in the tail of the queue for this
 2756          * group into which the first group record for this group will fit.
 2757          * Otherwise allocate a new packet.
 2758          * Always allocate leading space for IP+RA_OPT+IGMP+REPORT.
 2759          * Note: Group records for G/GSR query responses MUST be sent
 2760          * in their own packet.
 2761          */
 2762         m0 = ifq->ifq_tail;
 2763         if (!is_group_query &&
 2764             m0 != NULL &&
 2765             (m0->m_pkthdr.PH_vt.vt_nrecs + 1 <= IGMP_V3_REPORT_MAXRECS) &&
 2766             (m0->m_pkthdr.len + minrec0len) <
 2767              (ifp->if_mtu - IGMP_LEADINGSPACE)) {
 2768                 m0srcs = (ifp->if_mtu - m0->m_pkthdr.len -
 2769                             sizeof(struct igmp_grouprec)) / sizeof(in_addr_t);
 2770                 m = m0;
 2771                 CTR1(KTR_IGMPV3, "%s: use existing packet", __func__);
 2772         } else {
 2773                 if (_IF_QFULL(ifq)) {
 2774                         CTR1(KTR_IGMPV3, "%s: outbound queue full", __func__);
 2775                         return (-ENOMEM);
 2776                 }
 2777                 m = NULL;
 2778                 m0srcs = (ifp->if_mtu - IGMP_LEADINGSPACE -
 2779                     sizeof(struct igmp_grouprec)) / sizeof(in_addr_t);
 2780                 if (!is_state_change && !is_group_query) {
 2781                         m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
 2782                         if (m)
 2783                                 m->m_data += IGMP_LEADINGSPACE;
 2784                 }
 2785                 if (m == NULL) {
 2786                         m = m_gethdr(M_DONTWAIT, MT_DATA);
 2787                         if (m)
 2788                                 MH_ALIGN(m, IGMP_LEADINGSPACE);
 2789                 }
 2790                 if (m == NULL)
 2791                         return (-ENOMEM);
 2792 
 2793                 igmp_save_context(m, ifp);
 2794 
 2795                 CTR1(KTR_IGMPV3, "%s: allocated first packet", __func__);
 2796         }
 2797 
 2798         /*
 2799          * Append group record.
 2800          * If we have sources, we don't know how many yet.
 2801          */
 2802         ig.ig_type = type;
 2803         ig.ig_datalen = 0;
 2804         ig.ig_numsrc = 0;
 2805         ig.ig_group = inm->inm_addr;
 2806         if (!m_append(m, sizeof(struct igmp_grouprec), (void *)&ig)) {
 2807                 if (m != m0)
 2808                         m_freem(m);
 2809                 CTR1(KTR_IGMPV3, "%s: m_append() failed.", __func__);
 2810                 return (-ENOMEM);
 2811         }
 2812         nbytes += sizeof(struct igmp_grouprec);
 2813 
 2814         /*
 2815          * Append as many sources as will fit in the first packet.
 2816          * If we are appending to a new packet, the chain allocation
 2817          * may potentially use clusters; use m_getptr() in this case.
 2818          * If we are appending to an existing packet, we need to obtain
 2819          * a pointer to the group record after m_append(), in case a new
 2820          * mbuf was allocated.
 2821          * Only append sources which are in-mode at t1. If we are
 2822          * transitioning to MCAST_UNDEFINED state on the group, do not
 2823          * include source entries.
 2824          * Only report recorded sources in our filter set when responding
 2825          * to a group-source query.
 2826          */
 2827         if (record_has_sources) {
 2828                 if (m == m0) {
 2829                         md = m_last(m);
 2830                         pig = (struct igmp_grouprec *)(mtod(md, uint8_t *) +
 2831                             md->m_len - nbytes);
 2832                 } else {
 2833                         md = m_getptr(m, 0, &off);
 2834                         pig = (struct igmp_grouprec *)(mtod(md, uint8_t *) +
 2835                             off);
 2836                 }
 2837                 msrcs = 0;
 2838                 RB_FOREACH_SAFE(ims, ip_msource_tree, &inm->inm_srcs, nims) {
 2839                         CTR2(KTR_IGMPV3, "%s: visit node %s", __func__,
 2840                             inet_ntoa_haddr(ims->ims_haddr));
 2841                         now = ims_get_mode(inm, ims, 1);
 2842                         CTR2(KTR_IGMPV3, "%s: node is %d", __func__, now);
 2843                         if ((now != mode) ||
 2844                             (now == mode && mode == MCAST_UNDEFINED)) {
 2845                                 CTR1(KTR_IGMPV3, "%s: skip node", __func__);
 2846                                 continue;
 2847                         }
 2848                         if (is_source_query && ims->ims_stp == 0) {
 2849                                 CTR1(KTR_IGMPV3, "%s: skip unrecorded node",
 2850                                     __func__);
 2851                                 continue;
 2852                         }
 2853                         CTR1(KTR_IGMPV3, "%s: append node", __func__);
 2854                         naddr = htonl(ims->ims_haddr);
 2855                         if (!m_append(m, sizeof(in_addr_t), (void *)&naddr)) {
 2856                                 if (m != m0)
 2857                                         m_freem(m);
 2858                                 CTR1(KTR_IGMPV3, "%s: m_append() failed.",
 2859                                     __func__);
 2860                                 return (-ENOMEM);
 2861                         }
 2862                         nbytes += sizeof(in_addr_t);
 2863                         ++msrcs;
 2864                         if (msrcs == m0srcs)
 2865                                 break;
 2866                 }
 2867                 CTR2(KTR_IGMPV3, "%s: msrcs is %d this packet", __func__,
 2868                     msrcs);
 2869                 pig->ig_numsrc = htons(msrcs);
 2870                 nbytes += (msrcs * sizeof(in_addr_t));
 2871         }
 2872 
 2873         if (is_source_query && msrcs == 0) {
 2874                 CTR1(KTR_IGMPV3, "%s: no recorded sources to report", __func__);
 2875                 if (m != m0)
 2876                         m_freem(m);
 2877                 return (0);
 2878         }
 2879 
 2880         /*
 2881          * We are good to go with first packet.
 2882          */
 2883         if (m != m0) {
 2884                 CTR1(KTR_IGMPV3, "%s: enqueueing first packet", __func__);
 2885                 m->m_pkthdr.PH_vt.vt_nrecs = 1;
 2886                 _IF_ENQUEUE(ifq, m);
 2887         } else
 2888                 m->m_pkthdr.PH_vt.vt_nrecs++;
 2889 
 2890         /*
 2891          * No further work needed if no source list in packet(s).
 2892          */
 2893         if (!record_has_sources)
 2894                 return (nbytes);
 2895 
 2896         /*
 2897          * Whilst sources remain to be announced, we need to allocate
 2898          * a new packet and fill out as many sources as will fit.
 2899          * Always try for a cluster first.
 2900          */
 2901         while (nims != NULL) {
 2902                 if (_IF_QFULL(ifq)) {
 2903                         CTR1(KTR_IGMPV3, "%s: outbound queue full", __func__);
 2904                         return (-ENOMEM);
 2905                 }
 2906                 m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
 2907                 if (m)
 2908                         m->m_data += IGMP_LEADINGSPACE;
 2909                 if (m == NULL) {
 2910                         m = m_gethdr(M_DONTWAIT, MT_DATA);
 2911                         if (m)
 2912                                 MH_ALIGN(m, IGMP_LEADINGSPACE);
 2913                 }
 2914                 if (m == NULL)
 2915                         return (-ENOMEM);
 2916                 igmp_save_context(m, ifp);
 2917                 md = m_getptr(m, 0, &off);
 2918                 pig = (struct igmp_grouprec *)(mtod(md, uint8_t *) + off);
 2919                 CTR1(KTR_IGMPV3, "%s: allocated next packet", __func__);
 2920 
 2921                 if (!m_append(m, sizeof(struct igmp_grouprec), (void *)&ig)) {
 2922                         if (m != m0)
 2923                                 m_freem(m);
 2924                         CTR1(KTR_IGMPV3, "%s: m_append() failed.", __func__);
 2925                         return (-ENOMEM);
 2926                 }
 2927                 m->m_pkthdr.PH_vt.vt_nrecs = 1;
 2928                 nbytes += sizeof(struct igmp_grouprec);
 2929 
 2930                 m0srcs = (ifp->if_mtu - IGMP_LEADINGSPACE -
 2931                     sizeof(struct igmp_grouprec)) / sizeof(in_addr_t);
 2932 
 2933                 msrcs = 0;
 2934                 RB_FOREACH_FROM(ims, ip_msource_tree, nims) {
 2935                         CTR2(KTR_IGMPV3, "%s: visit node %s", __func__,
 2936                             inet_ntoa_haddr(ims->ims_haddr));
 2937                         now = ims_get_mode(inm, ims, 1);
 2938                         if ((now != mode) ||
 2939                             (now == mode && mode == MCAST_UNDEFINED)) {
 2940                                 CTR1(KTR_IGMPV3, "%s: skip node", __func__);
 2941                                 continue;
 2942                         }
 2943                         if (is_source_query && ims->ims_stp == 0) {
 2944                                 CTR1(KTR_IGMPV3, "%s: skip unrecorded node",
 2945                                     __func__);
 2946                                 continue;
 2947                         }
 2948                         CTR1(KTR_IGMPV3, "%s: append node", __func__);
 2949                         naddr = htonl(ims->ims_haddr);
 2950                         if (!m_append(m, sizeof(in_addr_t), (void *)&naddr)) {
 2951                                 if (m != m0)
 2952                                         m_freem(m);
 2953                                 CTR1(KTR_IGMPV3, "%s: m_append() failed.",
 2954                                     __func__);
 2955                                 return (-ENOMEM);
 2956                         }
 2957                         ++msrcs;
 2958                         if (msrcs == m0srcs)
 2959                                 break;
 2960                 }
 2961                 pig->ig_numsrc = htons(msrcs);
 2962                 nbytes += (msrcs * sizeof(in_addr_t));
 2963 
 2964                 CTR1(KTR_IGMPV3, "%s: enqueueing next packet", __func__);
 2965                 _IF_ENQUEUE(ifq, m);
 2966         }
 2967 
 2968         return (nbytes);
 2969 }
 2970 
 2971 /*
 2972  * Type used to mark record pass completion.
 2973  * We exploit the fact we can cast to this easily from the
 2974  * current filter modes on each ip_msource node.
 2975  */
 2976 typedef enum {
 2977         REC_NONE = 0x00,        /* MCAST_UNDEFINED */
 2978         REC_ALLOW = 0x01,       /* MCAST_INCLUDE */
 2979         REC_BLOCK = 0x02,       /* MCAST_EXCLUDE */
 2980         REC_FULL = REC_ALLOW | REC_BLOCK
 2981 } rectype_t;
 2982 
 2983 /*
 2984  * Enqueue an IGMPv3 filter list change to the given output queue.
 2985  *
 2986  * Source list filter state is held in an RB-tree. When the filter list
 2987  * for a group is changed without changing its mode, we need to compute
 2988  * the deltas between T0 and T1 for each source in the filter set,
 2989  * and enqueue the appropriate ALLOW_NEW/BLOCK_OLD records.
 2990  *
 2991  * As we may potentially queue two record types, and the entire R-B tree
 2992  * needs to be walked at once, we break this out into its own function
 2993  * so we can generate a tightly packed queue of packets.
 2994  *
 2995  * XXX This could be written to only use one tree walk, although that makes
 2996  * serializing into the mbuf chains a bit harder. For now we do two walks
 2997  * which makes things easier on us, and it may or may not be harder on
 2998  * the L2 cache.
 2999  *
 3000  * If successful the size of all data appended to the queue is returned,
 3001  * otherwise an error code less than zero is returned, or zero if
 3002  * no record(s) were appended.
 3003  */
 3004 static int
 3005 igmp_v3_enqueue_filter_change(struct ifqueue *ifq, struct in_multi *inm)
 3006 {
 3007         static const int MINRECLEN =
 3008             sizeof(struct igmp_grouprec) + sizeof(in_addr_t);
 3009         struct ifnet            *ifp;
 3010         struct igmp_grouprec     ig;
 3011         struct igmp_grouprec    *pig;
 3012         struct ip_msource       *ims, *nims;
 3013         struct mbuf             *m, *m0, *md;
 3014         in_addr_t                naddr;
 3015         int                      m0srcs, nbytes, npbytes, off, rsrcs, schanged;
 3016         int                      nallow, nblock;
 3017         uint8_t                  mode, now, then;
 3018         rectype_t                crt, drt, nrt;
 3019 
 3020         IN_MULTI_LOCK_ASSERT();
 3021 
 3022         if (inm->inm_nsrc == 0 ||
 3023             (inm->inm_st[0].iss_asm > 0 && inm->inm_st[1].iss_asm > 0))
 3024                 return (0);
 3025 
 3026         ifp = inm->inm_ifp;                     /* interface */
 3027         mode = inm->inm_st[1].iss_fmode;        /* filter mode at t1 */
 3028         crt = REC_NONE; /* current group record type */
 3029         drt = REC_NONE; /* mask of completed group record types */
 3030         nrt = REC_NONE; /* record type for current node */
 3031         m0srcs = 0;     /* # source which will fit in current mbuf chain */
 3032         nbytes = 0;     /* # of bytes appended to group's state-change queue */
 3033         npbytes = 0;    /* # of bytes appended this packet */
 3034         rsrcs = 0;      /* # sources encoded in current record */
 3035         schanged = 0;   /* # nodes encoded in overall filter change */
 3036         nallow = 0;     /* # of source entries in ALLOW_NEW */
 3037         nblock = 0;     /* # of source entries in BLOCK_OLD */
 3038         nims = NULL;    /* next tree node pointer */
 3039 
 3040         /*
 3041          * For each possible filter record mode.
 3042          * The first kind of source we encounter tells us which
 3043          * is the first kind of record we start appending.
 3044          * If a node transitioned to UNDEFINED at t1, its mode is treated
 3045          * as the inverse of the group's filter mode.
 3046          */
 3047         while (drt != REC_FULL) {
 3048                 do {
 3049                         m0 = ifq->ifq_tail;
 3050                         if (m0 != NULL &&
 3051                             (m0->m_pkthdr.PH_vt.vt_nrecs + 1 <=
 3052                              IGMP_V3_REPORT_MAXRECS) &&
 3053                             (m0->m_pkthdr.len + MINRECLEN) <
 3054                              (ifp->if_mtu - IGMP_LEADINGSPACE)) {
 3055                                 m = m0;
 3056                                 m0srcs = (ifp->if_mtu - m0->m_pkthdr.len -
 3057                                             sizeof(struct igmp_grouprec)) /
 3058                                     sizeof(in_addr_t);
 3059                                 CTR1(KTR_IGMPV3,
 3060                                     "%s: use previous packet", __func__);
 3061                         } else {
 3062                                 m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
 3063                                 if (m)
 3064                                         m->m_data += IGMP_LEADINGSPACE;
 3065                                 if (m == NULL) {
 3066                                         m = m_gethdr(M_DONTWAIT, MT_DATA);
 3067                                         if (m)
 3068                                                 MH_ALIGN(m, IGMP_LEADINGSPACE);
 3069                                 }
 3070                                 if (m == NULL) {
 3071                                         CTR1(KTR_IGMPV3,
 3072                                             "%s: m_get*() failed", __func__);
 3073                                         return (-ENOMEM);
 3074                                 }
 3075                                 m->m_pkthdr.PH_vt.vt_nrecs = 0;
 3076                                 igmp_save_context(m, ifp);
 3077                                 m0srcs = (ifp->if_mtu - IGMP_LEADINGSPACE -
 3078                                     sizeof(struct igmp_grouprec)) /
 3079                                     sizeof(in_addr_t);
 3080                                 npbytes = 0;
 3081                                 CTR1(KTR_IGMPV3,
 3082                                     "%s: allocated new packet", __func__);
 3083                         }
 3084                         /*
 3085                          * Append the IGMP group record header to the
 3086                          * current packet's data area.
 3087                          * Recalculate pointer to free space for next
 3088                          * group record, in case m_append() allocated
 3089                          * a new mbuf or cluster.
 3090                          */
 3091                         memset(&ig, 0, sizeof(ig));
 3092                         ig.ig_group = inm->inm_addr;
 3093                         if (!m_append(m, sizeof(ig), (void *)&ig)) {
 3094                                 if (m != m0)
 3095                                         m_freem(m);
 3096                                 CTR1(KTR_IGMPV3,
 3097                                     "%s: m_append() failed", __func__);
 3098                                 return (-ENOMEM);
 3099                         }
 3100                         npbytes += sizeof(struct igmp_grouprec);
 3101                         if (m != m0) {
 3102                                 /* new packet; offset in c hain */
 3103                                 md = m_getptr(m, npbytes -
 3104                                     sizeof(struct igmp_grouprec), &off);
 3105                                 pig = (struct igmp_grouprec *)(mtod(md,
 3106                                     uint8_t *) + off);
 3107                         } else {
 3108                                 /* current packet; offset from last append */
 3109                                 md = m_last(m);
 3110                                 pig = (struct igmp_grouprec *)(mtod(md,
 3111                                     uint8_t *) + md->m_len -
 3112                                     sizeof(struct igmp_grouprec));
 3113                         }
 3114                         /*
 3115                          * Begin walking the tree for this record type
 3116                          * pass, or continue from where we left off
 3117                          * previously if we had to allocate a new packet.
 3118                          * Only report deltas in-mode at t1.
 3119                          * We need not report included sources as allowed
 3120                          * if we are in inclusive mode on the group,
 3121                          * however the converse is not true.
 3122                          */
 3123                         rsrcs = 0;
 3124                         if (nims == NULL)
 3125                                 nims = RB_MIN(ip_msource_tree, &inm->inm_srcs);
 3126                         RB_FOREACH_FROM(ims, ip_msource_tree, nims) {
 3127                                 CTR2(KTR_IGMPV3, "%s: visit node %s",
 3128                                     __func__, inet_ntoa_haddr(ims->ims_haddr));
 3129                                 now = ims_get_mode(inm, ims, 1);
 3130                                 then = ims_get_mode(inm, ims, 0);
 3131                                 CTR3(KTR_IGMPV3, "%s: mode: t0 %d, t1 %d",
 3132                                     __func__, then, now);
 3133                                 if (now == then) {
 3134                                         CTR1(KTR_IGMPV3,
 3135                                             "%s: skip unchanged", __func__);
 3136                                         continue;
 3137                                 }
 3138                                 if (mode == MCAST_EXCLUDE &&
 3139                                     now == MCAST_INCLUDE) {
 3140                                         CTR1(KTR_IGMPV3,
 3141                                             "%s: skip IN src on EX group",
 3142                                             __func__);
 3143                                         continue;
 3144                                 }
 3145                                 nrt = (rectype_t)now;
 3146                                 if (nrt == REC_NONE)
 3147                                         nrt = (rectype_t)(~mode & REC_FULL);
 3148                                 if (schanged++ == 0) {
 3149                                         crt = nrt;
 3150                                 } else if (crt != nrt)
 3151                                         continue;
 3152                                 naddr = htonl(ims->ims_haddr);
 3153                                 if (!m_append(m, sizeof(in_addr_t),
 3154                                     (void *)&naddr)) {
 3155                                         if (m != m0)
 3156                                                 m_freem(m);
 3157                                         CTR1(KTR_IGMPV3,
 3158                                             "%s: m_append() failed", __func__);
 3159                                         return (-ENOMEM);
 3160                                 }
 3161                                 nallow += !!(crt == REC_ALLOW);
 3162                                 nblock += !!(crt == REC_BLOCK);
 3163                                 if (++rsrcs == m0srcs)
 3164                                         break;
 3165                         }
 3166                         /*
 3167                          * If we did not append any tree nodes on this
 3168                          * pass, back out of allocations.
 3169                          */
 3170                         if (rsrcs == 0) {
 3171                                 npbytes -= sizeof(struct igmp_grouprec);
 3172                                 if (m != m0) {
 3173                                         CTR1(KTR_IGMPV3,
 3174                                             "%s: m_free(m)", __func__);
 3175                                         m_freem(m);
 3176                                 } else {
 3177                                         CTR1(KTR_IGMPV3,
 3178                                             "%s: m_adj(m, -ig)", __func__);
 3179                                         m_adj(m, -((int)sizeof(
 3180                                             struct igmp_grouprec)));
 3181                                 }
 3182                                 continue;
 3183                         }
 3184                         npbytes += (rsrcs * sizeof(in_addr_t));
 3185                         if (crt == REC_ALLOW)
 3186                                 pig->ig_type = IGMP_ALLOW_NEW_SOURCES;
 3187                         else if (crt == REC_BLOCK)
 3188                                 pig->ig_type = IGMP_BLOCK_OLD_SOURCES;
 3189                         pig->ig_numsrc = htons(rsrcs);
 3190                         /*
 3191                          * Count the new group record, and enqueue this
 3192                          * packet if it wasn't already queued.
 3193                          */
 3194                         m->m_pkthdr.PH_vt.vt_nrecs++;
 3195                         if (m != m0)
 3196                                 _IF_ENQUEUE(ifq, m);
 3197                         nbytes += npbytes;
 3198                 } while (nims != NULL);
 3199                 drt |= crt;
 3200                 crt = (~crt & REC_FULL);
 3201         }
 3202 
 3203         CTR3(KTR_IGMPV3, "%s: queued %d ALLOW_NEW, %d BLOCK_OLD", __func__,
 3204             nallow, nblock);
 3205 
 3206         return (nbytes);
 3207 }
 3208 
 3209 static int
 3210 igmp_v3_merge_state_changes(struct in_multi *inm, struct ifqueue *ifscq)
 3211 {
 3212         struct ifqueue  *gq;
 3213         struct mbuf     *m;             /* pending state-change */
 3214         struct mbuf     *m0;            /* copy of pending state-change */
 3215         struct mbuf     *mt;            /* last state-change in packet */
 3216         int              docopy, domerge;
 3217         u_int            recslen;
 3218 
 3219         docopy = 0;
 3220         domerge = 0;
 3221         recslen = 0;
 3222 
 3223         IN_MULTI_LOCK_ASSERT();
 3224         IGMP_LOCK_ASSERT();
 3225 
 3226         /*
 3227          * If there are further pending retransmissions, make a writable
 3228          * copy of each queued state-change message before merging.
 3229          */
 3230         if (inm->inm_scrv > 0)
 3231                 docopy = 1;
 3232 
 3233         gq = &inm->inm_scq;
 3234 #ifdef KTR
 3235         if (gq->ifq_head == NULL) {
 3236                 CTR2(KTR_IGMPV3, "%s: WARNING: queue for inm %p is empty",
 3237                     __func__, inm);
 3238         }
 3239 #endif
 3240 
 3241         m = gq->ifq_head;
 3242         while (m != NULL) {
 3243                 /*
 3244                  * Only merge the report into the current packet if
 3245                  * there is sufficient space to do so; an IGMPv3 report
 3246                  * packet may only contain 65,535 group records.
 3247                  * Always use a simple mbuf chain concatentation to do this,
 3248                  * as large state changes for single groups may have
 3249                  * allocated clusters.
 3250                  */
 3251                 domerge = 0;
 3252                 mt = ifscq->ifq_tail;
 3253                 if (mt != NULL) {
 3254                         recslen = m_length(m, NULL);
 3255 
 3256                         if ((mt->m_pkthdr.PH_vt.vt_nrecs +
 3257                             m->m_pkthdr.PH_vt.vt_nrecs <=
 3258                             IGMP_V3_REPORT_MAXRECS) &&
 3259                             (mt->m_pkthdr.len + recslen <=
 3260                             (inm->inm_ifp->if_mtu - IGMP_LEADINGSPACE)))
 3261                                 domerge = 1;
 3262                 }
 3263 
 3264                 if (!domerge && _IF_QFULL(gq)) {
 3265                         CTR2(KTR_IGMPV3,
 3266                             "%s: outbound queue full, skipping whole packet %p",
 3267                             __func__, m);
 3268                         mt = m->m_nextpkt;
 3269                         if (!docopy)
 3270                                 m_freem(m);
 3271                         m = mt;
 3272                         continue;
 3273                 }
 3274 
 3275                 if (!docopy) {
 3276                         CTR2(KTR_IGMPV3, "%s: dequeueing %p", __func__, m);
 3277                         _IF_DEQUEUE(gq, m0);
 3278                         m = m0->m_nextpkt;
 3279                 } else {
 3280                         CTR2(KTR_IGMPV3, "%s: copying %p", __func__, m);
 3281                         m0 = m_dup(m, M_NOWAIT);
 3282                         if (m0 == NULL)
 3283                                 return (ENOMEM);
 3284                         m0->m_nextpkt = NULL;
 3285                         m = m->m_nextpkt;
 3286                 }
 3287 
 3288                 if (!domerge) {
 3289                         CTR3(KTR_IGMPV3, "%s: queueing %p to ifscq %p)",
 3290                             __func__, m0, ifscq);
 3291                         _IF_ENQUEUE(ifscq, m0);
 3292                 } else {
 3293                         struct mbuf *mtl;       /* last mbuf of packet mt */
 3294 
 3295                         CTR3(KTR_IGMPV3, "%s: merging %p with ifscq tail %p)",
 3296                             __func__, m0, mt);
 3297 
 3298                         mtl = m_last(mt);
 3299                         m0->m_flags &= ~M_PKTHDR;
 3300                         mt->m_pkthdr.len += recslen;
 3301                         mt->m_pkthdr.PH_vt.vt_nrecs +=
 3302                             m0->m_pkthdr.PH_vt.vt_nrecs;
 3303 
 3304                         mtl->m_next = m0;
 3305                 }
 3306         }
 3307 
 3308         return (0);
 3309 }
 3310 
 3311 /*
 3312  * Respond to a pending IGMPv3 General Query.
 3313  */
 3314 static void
 3315 igmp_v3_dispatch_general_query(struct igmp_ifinfo *igi)
 3316 {
 3317         struct ifmultiaddr      *ifma;
 3318         struct ifnet            *ifp;
 3319         struct in_multi         *inm;
 3320         int                      retval, loop;
 3321 
 3322         IN_MULTI_LOCK_ASSERT();
 3323         IGMP_LOCK_ASSERT();
 3324 
 3325         KASSERT(igi->igi_version == IGMP_VERSION_3,
 3326             ("%s: called when version %d", __func__, igi->igi_version));
 3327 
 3328         ifp = igi->igi_ifp;
 3329 
 3330         IF_ADDR_RLOCK(ifp);
 3331         TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
 3332                 if (ifma->ifma_addr->sa_family != AF_INET ||
 3333                     ifma->ifma_protospec == NULL)
 3334                         continue;
 3335 
 3336                 inm = (struct in_multi *)ifma->ifma_protospec;
 3337                 KASSERT(ifp == inm->inm_ifp,
 3338                     ("%s: inconsistent ifp", __func__));
 3339 
 3340                 switch (inm->inm_state) {
 3341                 case IGMP_NOT_MEMBER:
 3342                 case IGMP_SILENT_MEMBER:
 3343                         break;
 3344                 case IGMP_REPORTING_MEMBER:
 3345                 case IGMP_IDLE_MEMBER:
 3346                 case IGMP_LAZY_MEMBER:
 3347                 case IGMP_SLEEPING_MEMBER:
 3348                 case IGMP_AWAKENING_MEMBER:
 3349                         inm->inm_state = IGMP_REPORTING_MEMBER;
 3350                         retval = igmp_v3_enqueue_group_record(&igi->igi_gq,
 3351                             inm, 0, 0, 0);
 3352                         CTR2(KTR_IGMPV3, "%s: enqueue record = %d",
 3353                             __func__, retval);
 3354                         break;
 3355                 case IGMP_G_QUERY_PENDING_MEMBER:
 3356                 case IGMP_SG_QUERY_PENDING_MEMBER:
 3357                 case IGMP_LEAVING_MEMBER:
 3358                         break;
 3359                 }
 3360         }
 3361         IF_ADDR_RUNLOCK(ifp);
 3362 
 3363         loop = (igi->igi_flags & IGIF_LOOPBACK) ? 1 : 0;
 3364         igmp_dispatch_queue(&igi->igi_gq, IGMP_MAX_RESPONSE_BURST, loop);
 3365 
 3366         /*
 3367          * Slew transmission of bursts over 500ms intervals.
 3368          */
 3369         if (igi->igi_gq.ifq_head != NULL) {
 3370                 igi->igi_v3_timer = 1 + IGMP_RANDOM_DELAY(
 3371                     IGMP_RESPONSE_BURST_INTERVAL);
 3372                 V_interface_timers_running = 1;
 3373         }
 3374 }
 3375 
 3376 /*
 3377  * Transmit the next pending IGMP message in the output queue.
 3378  *
 3379  * We get called from netisr_processqueue(). A mutex private to igmpoq
 3380  * will be acquired and released around this routine.
 3381  *
 3382  * VIMAGE: Needs to store/restore vnet pointer on a per-mbuf-chain basis.
 3383  * MRT: Nothing needs to be done, as IGMP traffic is always local to
 3384  * a link and uses a link-scope multicast address.
 3385  */
 3386 static void
 3387 igmp_intr(struct mbuf *m)
 3388 {
 3389         struct ip_moptions       imo;
 3390         struct ifnet            *ifp;
 3391         struct mbuf             *ipopts, *m0;
 3392         int                      error;
 3393         uint32_t                 ifindex;
 3394 
 3395         CTR2(KTR_IGMPV3, "%s: transmit %p", __func__, m);
 3396 
 3397         /*
 3398          * Set VNET image pointer from enqueued mbuf chain
 3399          * before doing anything else. Whilst we use interface
 3400          * indexes to guard against interface detach, they are
 3401          * unique to each VIMAGE and must be retrieved.
 3402          */
 3403         CURVNET_SET((struct vnet *)(m->m_pkthdr.header));
 3404         ifindex = igmp_restore_context(m);
 3405 
 3406         /*
 3407          * Check if the ifnet still exists. This limits the scope of
 3408          * any race in the absence of a global ifp lock for low cost
 3409          * (an array lookup).
 3410          */
 3411         ifp = ifnet_byindex(ifindex);
 3412         if (ifp == NULL) {
 3413                 CTR3(KTR_IGMPV3, "%s: dropped %p as ifindex %u went away.",
 3414                     __func__, m, ifindex);
 3415                 m_freem(m);
 3416                 IPSTAT_INC(ips_noroute);
 3417                 goto out;
 3418         }
 3419 
 3420         ipopts = V_igmp_sendra ? m_raopt : NULL;
 3421 
 3422         imo.imo_multicast_ttl  = 1;
 3423         imo.imo_multicast_vif  = -1;
 3424         imo.imo_multicast_loop = (V_ip_mrouter != NULL);
 3425 
 3426         /*
 3427          * If the user requested that IGMP traffic be explicitly
 3428          * redirected to the loopback interface (e.g. they are running a
 3429          * MANET interface and the routing protocol needs to see the
 3430          * updates), handle this now.
 3431          */
 3432         if (m->m_flags & M_IGMP_LOOP)
 3433                 imo.imo_multicast_ifp = V_loif;
 3434         else
 3435                 imo.imo_multicast_ifp = ifp;
 3436 
 3437         if (m->m_flags & M_IGMPV2) {
 3438                 m0 = m;
 3439         } else {
 3440                 m0 = igmp_v3_encap_report(ifp, m);
 3441                 if (m0 == NULL) {
 3442                         CTR2(KTR_IGMPV3, "%s: dropped %p", __func__, m);
 3443                         m_freem(m);
 3444                         IPSTAT_INC(ips_odropped);
 3445                         goto out;
 3446                 }
 3447         }
 3448 
 3449         igmp_scrub_context(m0);
 3450         m->m_flags &= ~(M_PROTOFLAGS);
 3451         m0->m_pkthdr.rcvif = V_loif;
 3452 #ifdef MAC
 3453         mac_netinet_igmp_send(ifp, m0);
 3454 #endif
 3455         error = ip_output(m0, ipopts, NULL, 0, &imo, NULL);
 3456         if (error) {
 3457                 CTR3(KTR_IGMPV3, "%s: ip_output(%p) = %d", __func__, m0, error);
 3458                 goto out;
 3459         }
 3460 
 3461         IGMPSTAT_INC(igps_snd_reports);
 3462 
 3463 out:
 3464         /*
 3465          * We must restore the existing vnet pointer before
 3466          * continuing as we are run from netisr context.
 3467          */
 3468         CURVNET_RESTORE();
 3469 }
 3470 
 3471 /*
 3472  * Encapsulate an IGMPv3 report.
 3473  *
 3474  * The internal mbuf flag M_IGMPV3_HDR is used to indicate that the mbuf
 3475  * chain has already had its IP/IGMPv3 header prepended. In this case
 3476  * the function will not attempt to prepend; the lengths and checksums
 3477  * will however be re-computed.
 3478  *
 3479  * Returns a pointer to the new mbuf chain head, or NULL if the
 3480  * allocation failed.
 3481  */
 3482 static struct mbuf *
 3483 igmp_v3_encap_report(struct ifnet *ifp, struct mbuf *m)
 3484 {
 3485         struct igmp_report      *igmp;
 3486         struct ip               *ip;
 3487         int                      hdrlen, igmpreclen;
 3488 
 3489         KASSERT((m->m_flags & M_PKTHDR),
 3490             ("%s: mbuf chain %p is !M_PKTHDR", __func__, m));
 3491 
 3492         igmpreclen = m_length(m, NULL);
 3493         hdrlen = sizeof(struct ip) + sizeof(struct igmp_report);
 3494 
 3495         if (m->m_flags & M_IGMPV3_HDR) {
 3496                 igmpreclen -= hdrlen;
 3497         } else {
 3498                 M_PREPEND(m, hdrlen, M_DONTWAIT);
 3499                 if (m == NULL)
 3500                         return (NULL);
 3501                 m->m_flags |= M_IGMPV3_HDR;
 3502         }
 3503 
 3504         CTR2(KTR_IGMPV3, "%s: igmpreclen is %d", __func__, igmpreclen);
 3505 
 3506         m->m_data += sizeof(struct ip);
 3507         m->m_len -= sizeof(struct ip);
 3508 
 3509         igmp = mtod(m, struct igmp_report *);
 3510         igmp->ir_type = IGMP_v3_HOST_MEMBERSHIP_REPORT;
 3511         igmp->ir_rsv1 = 0;
 3512         igmp->ir_rsv2 = 0;
 3513         igmp->ir_numgrps = htons(m->m_pkthdr.PH_vt.vt_nrecs);
 3514         igmp->ir_cksum = 0;
 3515         igmp->ir_cksum = in_cksum(m, sizeof(struct igmp_report) + igmpreclen);
 3516         m->m_pkthdr.PH_vt.vt_nrecs = 0;
 3517 
 3518         m->m_data -= sizeof(struct ip);
 3519         m->m_len += sizeof(struct ip);
 3520 
 3521         ip = mtod(m, struct ip *);
 3522         ip->ip_tos = IPTOS_PREC_INTERNETCONTROL;
 3523         ip->ip_len = hdrlen + igmpreclen;
 3524         ip->ip_off = IP_DF;
 3525         ip->ip_p = IPPROTO_IGMP;
 3526         ip->ip_sum = 0;
 3527 
 3528         ip->ip_src.s_addr = INADDR_ANY;
 3529 
 3530         if (m->m_flags & M_IGMP_LOOP) {
 3531                 struct in_ifaddr *ia;
 3532 
 3533                 IFP_TO_IA(ifp, ia);
 3534                 if (ia != NULL) {
 3535                         ip->ip_src = ia->ia_addr.sin_addr;
 3536                         ifa_free(&ia->ia_ifa);
 3537                 }
 3538         }
 3539 
 3540         ip->ip_dst.s_addr = htonl(INADDR_ALLRPTS_GROUP);
 3541 
 3542         return (m);
 3543 }
 3544 
 3545 #ifdef KTR
 3546 static char *
 3547 igmp_rec_type_to_str(const int type)
 3548 {
 3549 
 3550         switch (type) {
 3551                 case IGMP_CHANGE_TO_EXCLUDE_MODE:
 3552                         return "TO_EX";
 3553                         break;
 3554                 case IGMP_CHANGE_TO_INCLUDE_MODE:
 3555                         return "TO_IN";
 3556                         break;
 3557                 case IGMP_MODE_IS_EXCLUDE:
 3558                         return "MODE_EX";
 3559                         break;
 3560                 case IGMP_MODE_IS_INCLUDE:
 3561                         return "MODE_IN";
 3562                         break;
 3563                 case IGMP_ALLOW_NEW_SOURCES:
 3564                         return "ALLOW_NEW";
 3565                         break;
 3566                 case IGMP_BLOCK_OLD_SOURCES:
 3567                         return "BLOCK_OLD";
 3568                         break;
 3569                 default:
 3570                         break;
 3571         }
 3572         return "unknown";
 3573 }
 3574 #endif
 3575 
 3576 static void
 3577 igmp_init(void *unused __unused)
 3578 {
 3579 
 3580         CTR1(KTR_IGMPV3, "%s: initializing", __func__);
 3581 
 3582         IGMP_LOCK_INIT();
 3583 
 3584         m_raopt = igmp_ra_alloc();
 3585 
 3586         netisr_register(&igmp_nh);
 3587 }
 3588 SYSINIT(igmp_init, SI_SUB_PSEUDO, SI_ORDER_MIDDLE, igmp_init, NULL);
 3589 
 3590 static void
 3591 igmp_uninit(void *unused __unused)
 3592 {
 3593 
 3594         CTR1(KTR_IGMPV3, "%s: tearing down", __func__);
 3595 
 3596         netisr_unregister(&igmp_nh);
 3597 
 3598         m_free(m_raopt);
 3599         m_raopt = NULL;
 3600 
 3601         IGMP_LOCK_DESTROY();
 3602 }
 3603 SYSUNINIT(igmp_uninit, SI_SUB_PSEUDO, SI_ORDER_MIDDLE, igmp_uninit, NULL);
 3604 
 3605 static void
 3606 vnet_igmp_init(const void *unused __unused)
 3607 {
 3608 
 3609         CTR1(KTR_IGMPV3, "%s: initializing", __func__);
 3610 
 3611         LIST_INIT(&V_igi_head);
 3612 }
 3613 VNET_SYSINIT(vnet_igmp_init, SI_SUB_PSEUDO, SI_ORDER_ANY, vnet_igmp_init,
 3614     NULL);
 3615 
 3616 static void
 3617 vnet_igmp_uninit(const void *unused __unused)
 3618 {
 3619 
 3620         CTR1(KTR_IGMPV3, "%s: tearing down", __func__);
 3621 
 3622         KASSERT(LIST_EMPTY(&V_igi_head),
 3623             ("%s: igi list not empty; ifnets not detached?", __func__));
 3624 }
 3625 VNET_SYSUNINIT(vnet_igmp_uninit, SI_SUB_PSEUDO, SI_ORDER_ANY,
 3626     vnet_igmp_uninit, NULL);
 3627 
 3628 static int
 3629 igmp_modevent(module_t mod, int type, void *unused __unused)
 3630 {
 3631 
 3632     switch (type) {
 3633     case MOD_LOAD:
 3634     case MOD_UNLOAD:
 3635         break;
 3636     default:
 3637         return (EOPNOTSUPP);
 3638     }
 3639     return (0);
 3640 }
 3641 
 3642 static moduledata_t igmp_mod = {
 3643     "igmp",
 3644     igmp_modevent,
 3645     0
 3646 };
 3647 DECLARE_MODULE(igmp, igmp_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);

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