The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/netinet/igmp.c

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    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/11.1/sys/netinet/igmp.c 315456 2017-03-17 14:54:10Z vangyzen $");
   52 
   53 #include "opt_ddb.h"
   54 
   55 #include <sys/param.h>
   56 #include <sys/systm.h>
   57 #include <sys/module.h>
   58 #include <sys/malloc.h>
   59 #include <sys/mbuf.h>
   60 #include <sys/socket.h>
   61 #include <sys/protosw.h>
   62 #include <sys/kernel.h>
   63 #include <sys/lock.h>
   64 #include <sys/rmlock.h>
   65 #include <sys/sysctl.h>
   66 #include <sys/ktr.h>
   67 #include <sys/condvar.h>
   68 
   69 #ifdef DDB
   70 #include <ddb/ddb.h>
   71 #endif
   72 
   73 #include <net/if.h>
   74 #include <net/if_var.h>
   75 #include <net/netisr.h>
   76 #include <net/vnet.h>
   77 
   78 #include <netinet/in.h>
   79 #include <netinet/in_var.h>
   80 #include <netinet/in_systm.h>
   81 #include <netinet/ip.h>
   82 #include <netinet/ip_var.h>
   83 #include <netinet/ip_options.h>
   84 #include <netinet/igmp.h>
   85 #include <netinet/igmp_var.h>
   86 
   87 #include <machine/in_cksum.h>
   88 
   89 #include <security/mac/mac_framework.h>
   90 
   91 #ifndef KTR_IGMPV3
   92 #define KTR_IGMPV3 KTR_INET
   93 #endif
   94 
   95 static struct igmp_ifsoftc *
   96                 igi_alloc_locked(struct ifnet *);
   97 static void     igi_delete_locked(const struct ifnet *);
   98 static void     igmp_dispatch_queue(struct mbufq *, int, const int);
   99 static void     igmp_fasttimo_vnet(void);
  100 static void     igmp_final_leave(struct in_multi *, struct igmp_ifsoftc *);
  101 static int      igmp_handle_state_change(struct in_multi *,
  102                     struct igmp_ifsoftc *);
  103 static int      igmp_initial_join(struct in_multi *, struct igmp_ifsoftc *);
  104 static int      igmp_input_v1_query(struct ifnet *, const struct ip *,
  105                     const struct igmp *);
  106 static int      igmp_input_v2_query(struct ifnet *, const struct ip *,
  107                     const struct igmp *);
  108 static int      igmp_input_v3_query(struct ifnet *, const struct ip *,
  109                     /*const*/ struct igmpv3 *);
  110 static int      igmp_input_v3_group_query(struct in_multi *,
  111                     struct igmp_ifsoftc *, int, /*const*/ struct igmpv3 *);
  112 static int      igmp_input_v1_report(struct ifnet *, /*const*/ struct ip *,
  113                     /*const*/ struct igmp *);
  114 static int      igmp_input_v2_report(struct ifnet *, /*const*/ struct ip *,
  115                     /*const*/ struct igmp *);
  116 static void     igmp_intr(struct mbuf *);
  117 static int      igmp_isgroupreported(const struct in_addr);
  118 static struct mbuf *
  119                 igmp_ra_alloc(void);
  120 #ifdef KTR
  121 static char *   igmp_rec_type_to_str(const int);
  122 #endif
  123 static void     igmp_set_version(struct igmp_ifsoftc *, const int);
  124 static void     igmp_slowtimo_vnet(void);
  125 static int      igmp_v1v2_queue_report(struct in_multi *, const int);
  126 static void     igmp_v1v2_process_group_timer(struct in_multi *, const int);
  127 static void     igmp_v1v2_process_querier_timers(struct igmp_ifsoftc *);
  128 static void     igmp_v2_update_group(struct in_multi *, const int);
  129 static void     igmp_v3_cancel_link_timers(struct igmp_ifsoftc *);
  130 static void     igmp_v3_dispatch_general_query(struct igmp_ifsoftc *);
  131 static struct mbuf *
  132                 igmp_v3_encap_report(struct ifnet *, struct mbuf *);
  133 static int      igmp_v3_enqueue_group_record(struct mbufq *,
  134                     struct in_multi *, const int, const int, const int);
  135 static int      igmp_v3_enqueue_filter_change(struct mbufq *,
  136                     struct in_multi *);
  137 static void     igmp_v3_process_group_timers(struct igmp_ifsoftc *,
  138                     struct mbufq *, struct mbufq *, struct in_multi *,
  139                     const int);
  140 static int      igmp_v3_merge_state_changes(struct in_multi *,
  141                     struct mbufq *);
  142 static void     igmp_v3_suppress_group_record(struct in_multi *);
  143 static int      sysctl_igmp_default_version(SYSCTL_HANDLER_ARGS);
  144 static int      sysctl_igmp_gsr(SYSCTL_HANDLER_ARGS);
  145 static int      sysctl_igmp_ifinfo(SYSCTL_HANDLER_ARGS);
  146 
  147 static const struct netisr_handler igmp_nh = {
  148         .nh_name = "igmp",
  149         .nh_handler = igmp_intr,
  150         .nh_proto = NETISR_IGMP,
  151         .nh_policy = NETISR_POLICY_SOURCE,
  152 };
  153 
  154 /*
  155  * System-wide globals.
  156  *
  157  * Unlocked access to these is OK, except for the global IGMP output
  158  * queue. The IGMP subsystem lock ends up being system-wide for the moment,
  159  * because all VIMAGEs have to share a global output queue, as netisrs
  160  * themselves are not virtualized.
  161  *
  162  * Locking:
  163  *  * The permitted lock order is: IN_MULTI_LOCK, IGMP_LOCK, IF_ADDR_LOCK.
  164  *    Any may be taken independently; if any are held at the same
  165  *    time, the above lock order must be followed.
  166  *  * All output is delegated to the netisr.
  167  *    Now that Giant has been eliminated, the netisr may be inlined.
  168  *  * IN_MULTI_LOCK covers in_multi.
  169  *  * IGMP_LOCK covers igmp_ifsoftc and any global variables in this file,
  170  *    including the output queue.
  171  *  * IF_ADDR_LOCK covers if_multiaddrs, which is used for a variety of
  172  *    per-link state iterators.
  173  *  * igmp_ifsoftc is valid as long as PF_INET is attached to the interface,
  174  *    therefore it is not refcounted.
  175  *    We allow unlocked reads of igmp_ifsoftc when accessed via in_multi.
  176  *
  177  * Reference counting
  178  *  * IGMP acquires its own reference every time an in_multi is passed to
  179  *    it and the group is being joined for the first time.
  180  *  * IGMP releases its reference(s) on in_multi in a deferred way,
  181  *    because the operations which process the release run as part of
  182  *    a loop whose control variables are directly affected by the release
  183  *    (that, and not recursing on the IF_ADDR_LOCK).
  184  *
  185  * VIMAGE: Each in_multi corresponds to an ifp, and each ifp corresponds
  186  * to a vnet in ifp->if_vnet.
  187  *
  188  * SMPng: XXX We may potentially race operations on ifma_protospec.
  189  * The problem is that we currently lack a clean way of taking the
  190  * IF_ADDR_LOCK() between the ifnet and in layers w/o recursing,
  191  * as anything which modifies ifma needs to be covered by that lock.
  192  * So check for ifma_protospec being NULL before proceeding.
  193  */
  194 struct mtx               igmp_mtx;
  195 
  196 struct mbuf             *m_raopt;                /* Router Alert option */
  197 static MALLOC_DEFINE(M_IGMP, "igmp", "igmp state");
  198 
  199 /*
  200  * VIMAGE-wide globals.
  201  *
  202  * The IGMPv3 timers themselves need to run per-image, however,
  203  * protosw timers run globally (see tcp).
  204  * An ifnet can only be in one vimage at a time, and the loopback
  205  * ifnet, loif, is itself virtualized.
  206  * It would otherwise be possible to seriously hose IGMP state,
  207  * and create inconsistencies in upstream multicast routing, if you have
  208  * multiple VIMAGEs running on the same link joining different multicast
  209  * groups, UNLESS the "primary IP address" is different. This is because
  210  * IGMP for IPv4 does not force link-local addresses to be used for each
  211  * node, unlike MLD for IPv6.
  212  * Obviously the IGMPv3 per-interface state has per-vimage granularity
  213  * also as a result.
  214  *
  215  * FUTURE: Stop using IFP_TO_IA/INADDR_ANY, and use source address selection
  216  * policy to control the address used by IGMP on the link.
  217  */
  218 static VNET_DEFINE(int, interface_timers_running);      /* IGMPv3 general
  219                                                          * query response */
  220 static VNET_DEFINE(int, state_change_timers_running);   /* IGMPv3 state-change
  221                                                          * retransmit */
  222 static VNET_DEFINE(int, current_state_timers_running);  /* IGMPv1/v2 host
  223                                                          * report; IGMPv3 g/sg
  224                                                          * query response */
  225 
  226 #define V_interface_timers_running      VNET(interface_timers_running)
  227 #define V_state_change_timers_running   VNET(state_change_timers_running)
  228 #define V_current_state_timers_running  VNET(current_state_timers_running)
  229 
  230 static VNET_DEFINE(LIST_HEAD(, igmp_ifsoftc), igi_head) =
  231     LIST_HEAD_INITIALIZER(igi_head);
  232 static VNET_DEFINE(struct igmpstat, igmpstat) = {
  233         .igps_version = IGPS_VERSION_3,
  234         .igps_len = sizeof(struct igmpstat),
  235 };
  236 static VNET_DEFINE(struct timeval, igmp_gsrdelay) = {10, 0};
  237 
  238 #define V_igi_head                      VNET(igi_head)
  239 #define V_igmpstat                      VNET(igmpstat)
  240 #define V_igmp_gsrdelay                 VNET(igmp_gsrdelay)
  241 
  242 static VNET_DEFINE(int, igmp_recvifkludge) = 1;
  243 static VNET_DEFINE(int, igmp_sendra) = 1;
  244 static VNET_DEFINE(int, igmp_sendlocal) = 1;
  245 static VNET_DEFINE(int, igmp_v1enable) = 1;
  246 static VNET_DEFINE(int, igmp_v2enable) = 1;
  247 static VNET_DEFINE(int, igmp_legacysupp);
  248 static VNET_DEFINE(int, igmp_default_version) = IGMP_VERSION_3;
  249 
  250 #define V_igmp_recvifkludge             VNET(igmp_recvifkludge)
  251 #define V_igmp_sendra                   VNET(igmp_sendra)
  252 #define V_igmp_sendlocal                VNET(igmp_sendlocal)
  253 #define V_igmp_v1enable                 VNET(igmp_v1enable)
  254 #define V_igmp_v2enable                 VNET(igmp_v2enable)
  255 #define V_igmp_legacysupp               VNET(igmp_legacysupp)
  256 #define V_igmp_default_version          VNET(igmp_default_version)
  257 
  258 /*
  259  * Virtualized sysctls.
  260  */
  261 SYSCTL_STRUCT(_net_inet_igmp, IGMPCTL_STATS, stats, CTLFLAG_VNET | CTLFLAG_RW,
  262     &VNET_NAME(igmpstat), igmpstat, "");
  263 SYSCTL_INT(_net_inet_igmp, OID_AUTO, recvifkludge, CTLFLAG_VNET | CTLFLAG_RW,
  264     &VNET_NAME(igmp_recvifkludge), 0,
  265     "Rewrite IGMPv1/v2 reports from 0.0.0.0 to contain subnet address");
  266 SYSCTL_INT(_net_inet_igmp, OID_AUTO, sendra, CTLFLAG_VNET | CTLFLAG_RW,
  267     &VNET_NAME(igmp_sendra), 0,
  268     "Send IP Router Alert option in IGMPv2/v3 messages");
  269 SYSCTL_INT(_net_inet_igmp, OID_AUTO, sendlocal, CTLFLAG_VNET | CTLFLAG_RW,
  270     &VNET_NAME(igmp_sendlocal), 0,
  271     "Send IGMP membership reports for 224.0.0.0/24 groups");
  272 SYSCTL_INT(_net_inet_igmp, OID_AUTO, v1enable, CTLFLAG_VNET | CTLFLAG_RW,
  273     &VNET_NAME(igmp_v1enable), 0,
  274     "Enable backwards compatibility with IGMPv1");
  275 SYSCTL_INT(_net_inet_igmp, OID_AUTO, v2enable, CTLFLAG_VNET | CTLFLAG_RW,
  276     &VNET_NAME(igmp_v2enable), 0,
  277     "Enable backwards compatibility with IGMPv2");
  278 SYSCTL_INT(_net_inet_igmp, OID_AUTO, legacysupp, CTLFLAG_VNET | CTLFLAG_RW,
  279     &VNET_NAME(igmp_legacysupp), 0,
  280     "Allow v1/v2 reports to suppress v3 group responses");
  281 SYSCTL_PROC(_net_inet_igmp, OID_AUTO, default_version,
  282     CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
  283     &VNET_NAME(igmp_default_version), 0, sysctl_igmp_default_version, "I",
  284     "Default version of IGMP to run on each interface");
  285 SYSCTL_PROC(_net_inet_igmp, OID_AUTO, gsrdelay,
  286     CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
  287     &VNET_NAME(igmp_gsrdelay.tv_sec), 0, sysctl_igmp_gsr, "I",
  288     "Rate limit for IGMPv3 Group-and-Source queries in seconds");
  289 
  290 /*
  291  * Non-virtualized sysctls.
  292  */
  293 static SYSCTL_NODE(_net_inet_igmp, OID_AUTO, ifinfo,
  294     CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_igmp_ifinfo,
  295     "Per-interface IGMPv3 state");
  296 
  297 static __inline void
  298 igmp_save_context(struct mbuf *m, struct ifnet *ifp)
  299 {
  300 
  301 #ifdef VIMAGE
  302         m->m_pkthdr.PH_loc.ptr = ifp->if_vnet;
  303 #endif /* VIMAGE */
  304         m->m_pkthdr.flowid = ifp->if_index;
  305 }
  306 
  307 static __inline void
  308 igmp_scrub_context(struct mbuf *m)
  309 {
  310 
  311         m->m_pkthdr.PH_loc.ptr = NULL;
  312         m->m_pkthdr.flowid = 0;
  313 }
  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.PH_loc.ptr),
  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_ifsoftc 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_ifsoftc     *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                         struct igmp_ifinfo info;
  459 
  460                         info.igi_version = igi->igi_version;
  461                         info.igi_v1_timer = igi->igi_v1_timer;
  462                         info.igi_v2_timer = igi->igi_v2_timer;
  463                         info.igi_v3_timer = igi->igi_v3_timer;
  464                         info.igi_flags = igi->igi_flags;
  465                         info.igi_rv = igi->igi_rv;
  466                         info.igi_qi = igi->igi_qi;
  467                         info.igi_qri = igi->igi_qri;
  468                         info.igi_uri = igi->igi_uri;
  469                         error = SYSCTL_OUT(req, &info, sizeof(info));
  470                         break;
  471                 }
  472         }
  473 
  474 out_locked:
  475         IGMP_UNLOCK();
  476         IN_MULTI_UNLOCK();
  477         return (error);
  478 }
  479 
  480 /*
  481  * Dispatch an entire queue of pending packet chains
  482  * using the netisr.
  483  * VIMAGE: Assumes the vnet pointer has been set.
  484  */
  485 static void
  486 igmp_dispatch_queue(struct mbufq *mq, int limit, const int loop)
  487 {
  488         struct mbuf *m;
  489 
  490         while ((m = mbufq_dequeue(mq)) != NULL) {
  491                 CTR3(KTR_IGMPV3, "%s: dispatch %p from %p", __func__, mq, m);
  492                 if (loop)
  493                         m->m_flags |= M_IGMP_LOOP;
  494                 netisr_dispatch(NETISR_IGMP, m);
  495                 if (--limit == 0)
  496                         break;
  497         }
  498 }
  499 
  500 /*
  501  * Filter outgoing IGMP report state by group.
  502  *
  503  * Reports are ALWAYS suppressed for ALL-HOSTS (224.0.0.1).
  504  * If the net.inet.igmp.sendlocal sysctl is 0, then IGMP reports are
  505  * disabled for all groups in the 224.0.0.0/24 link-local scope. However,
  506  * this may break certain IGMP snooping switches which rely on the old
  507  * report behaviour.
  508  *
  509  * Return zero if the given group is one for which IGMP reports
  510  * should be suppressed, or non-zero if reports should be issued.
  511  */
  512 static __inline int
  513 igmp_isgroupreported(const struct in_addr addr)
  514 {
  515 
  516         if (in_allhosts(addr) ||
  517             ((!V_igmp_sendlocal && IN_LOCAL_GROUP(ntohl(addr.s_addr)))))
  518                 return (0);
  519 
  520         return (1);
  521 }
  522 
  523 /*
  524  * Construct a Router Alert option to use in outgoing packets.
  525  */
  526 static struct mbuf *
  527 igmp_ra_alloc(void)
  528 {
  529         struct mbuf     *m;
  530         struct ipoption *p;
  531 
  532         m = m_get(M_WAITOK, MT_DATA);
  533         p = mtod(m, struct ipoption *);
  534         p->ipopt_dst.s_addr = INADDR_ANY;
  535         p->ipopt_list[0] = (char)IPOPT_RA;      /* Router Alert Option */
  536         p->ipopt_list[1] = 0x04;                /* 4 bytes long */
  537         p->ipopt_list[2] = IPOPT_EOL;           /* End of IP option list */
  538         p->ipopt_list[3] = 0x00;                /* pad byte */
  539         m->m_len = sizeof(p->ipopt_dst) + p->ipopt_list[1];
  540 
  541         return (m);
  542 }
  543 
  544 /*
  545  * Attach IGMP when PF_INET is attached to an interface.
  546  */
  547 struct igmp_ifsoftc *
  548 igmp_domifattach(struct ifnet *ifp)
  549 {
  550         struct igmp_ifsoftc *igi;
  551 
  552         CTR3(KTR_IGMPV3, "%s: called for ifp %p(%s)",
  553             __func__, ifp, ifp->if_xname);
  554 
  555         IGMP_LOCK();
  556 
  557         igi = igi_alloc_locked(ifp);
  558         if (!(ifp->if_flags & IFF_MULTICAST))
  559                 igi->igi_flags |= IGIF_SILENT;
  560 
  561         IGMP_UNLOCK();
  562 
  563         return (igi);
  564 }
  565 
  566 /*
  567  * VIMAGE: assume curvnet set by caller.
  568  */
  569 static struct igmp_ifsoftc *
  570 igi_alloc_locked(/*const*/ struct ifnet *ifp)
  571 {
  572         struct igmp_ifsoftc *igi;
  573 
  574         IGMP_LOCK_ASSERT();
  575 
  576         igi = malloc(sizeof(struct igmp_ifsoftc), M_IGMP, M_NOWAIT|M_ZERO);
  577         if (igi == NULL)
  578                 goto out;
  579 
  580         igi->igi_ifp = ifp;
  581         igi->igi_version = V_igmp_default_version;
  582         igi->igi_flags = 0;
  583         igi->igi_rv = IGMP_RV_INIT;
  584         igi->igi_qi = IGMP_QI_INIT;
  585         igi->igi_qri = IGMP_QRI_INIT;
  586         igi->igi_uri = IGMP_URI_INIT;
  587         SLIST_INIT(&igi->igi_relinmhead);
  588         mbufq_init(&igi->igi_gq, IGMP_MAX_RESPONSE_PACKETS);
  589 
  590         LIST_INSERT_HEAD(&V_igi_head, igi, igi_link);
  591 
  592         CTR2(KTR_IGMPV3, "allocate igmp_ifsoftc for ifp %p(%s)",
  593              ifp, ifp->if_xname);
  594 
  595 out:
  596         return (igi);
  597 }
  598 
  599 /*
  600  * Hook for ifdetach.
  601  *
  602  * NOTE: Some finalization tasks need to run before the protocol domain
  603  * is detached, but also before the link layer does its cleanup.
  604  *
  605  * SMPNG: igmp_ifdetach() needs to take IF_ADDR_LOCK().
  606  * XXX This is also bitten by unlocked ifma_protospec access.
  607  */
  608 void
  609 igmp_ifdetach(struct ifnet *ifp)
  610 {
  611         struct igmp_ifsoftc     *igi;
  612         struct ifmultiaddr      *ifma;
  613         struct in_multi         *inm, *tinm;
  614 
  615         CTR3(KTR_IGMPV3, "%s: called for ifp %p(%s)", __func__, ifp,
  616             ifp->if_xname);
  617 
  618         IGMP_LOCK();
  619 
  620         igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
  621         if (igi->igi_version == IGMP_VERSION_3) {
  622                 IF_ADDR_RLOCK(ifp);
  623                 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
  624                         if (ifma->ifma_addr->sa_family != AF_INET ||
  625                             ifma->ifma_protospec == NULL)
  626                                 continue;
  627 #if 0
  628                         KASSERT(ifma->ifma_protospec != NULL,
  629                             ("%s: ifma_protospec is NULL", __func__));
  630 #endif
  631                         inm = (struct in_multi *)ifma->ifma_protospec;
  632                         if (inm->inm_state == IGMP_LEAVING_MEMBER) {
  633                                 SLIST_INSERT_HEAD(&igi->igi_relinmhead,
  634                                     inm, inm_nrele);
  635                         }
  636                         inm_clear_recorded(inm);
  637                 }
  638                 IF_ADDR_RUNLOCK(ifp);
  639                 /*
  640                  * Free the in_multi reference(s) for this IGMP lifecycle.
  641                  */
  642                 SLIST_FOREACH_SAFE(inm, &igi->igi_relinmhead, inm_nrele,
  643                     tinm) {
  644                         SLIST_REMOVE_HEAD(&igi->igi_relinmhead, inm_nrele);
  645                         inm_release_locked(inm);
  646                 }
  647         }
  648 
  649         IGMP_UNLOCK();
  650 }
  651 
  652 /*
  653  * Hook for domifdetach.
  654  */
  655 void
  656 igmp_domifdetach(struct ifnet *ifp)
  657 {
  658 
  659         CTR3(KTR_IGMPV3, "%s: called for ifp %p(%s)",
  660             __func__, ifp, ifp->if_xname);
  661 
  662         IGMP_LOCK();
  663         igi_delete_locked(ifp);
  664         IGMP_UNLOCK();
  665 }
  666 
  667 static void
  668 igi_delete_locked(const struct ifnet *ifp)
  669 {
  670         struct igmp_ifsoftc *igi, *tigi;
  671 
  672         CTR3(KTR_IGMPV3, "%s: freeing igmp_ifsoftc for ifp %p(%s)",
  673             __func__, ifp, ifp->if_xname);
  674 
  675         IGMP_LOCK_ASSERT();
  676 
  677         LIST_FOREACH_SAFE(igi, &V_igi_head, igi_link, tigi) {
  678                 if (igi->igi_ifp == ifp) {
  679                         /*
  680                          * Free deferred General Query responses.
  681                          */
  682                         mbufq_drain(&igi->igi_gq);
  683 
  684                         LIST_REMOVE(igi, igi_link);
  685 
  686                         KASSERT(SLIST_EMPTY(&igi->igi_relinmhead),
  687                             ("%s: there are dangling in_multi references",
  688                             __func__));
  689 
  690                         free(igi, M_IGMP);
  691                         return;
  692                 }
  693         }
  694 }
  695 
  696 /*
  697  * Process a received IGMPv1 query.
  698  * Return non-zero if the message should be dropped.
  699  *
  700  * VIMAGE: The curvnet pointer is derived from the input ifp.
  701  */
  702 static int
  703 igmp_input_v1_query(struct ifnet *ifp, const struct ip *ip,
  704     const struct igmp *igmp)
  705 {
  706         struct ifmultiaddr      *ifma;
  707         struct igmp_ifsoftc     *igi;
  708         struct in_multi         *inm;
  709 
  710         /*
  711          * IGMPv1 Host Mmembership Queries SHOULD always be addressed to
  712          * 224.0.0.1. They are always treated as General Queries.
  713          * igmp_group is always ignored. Do not drop it as a userland
  714          * daemon may wish to see it.
  715          * XXX SMPng: unlocked increments in igmpstat assumed atomic.
  716          */
  717         if (!in_allhosts(ip->ip_dst) || !in_nullhost(igmp->igmp_group)) {
  718                 IGMPSTAT_INC(igps_rcv_badqueries);
  719                 return (0);
  720         }
  721         IGMPSTAT_INC(igps_rcv_gen_queries);
  722 
  723         IN_MULTI_LOCK();
  724         IGMP_LOCK();
  725 
  726         igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
  727         KASSERT(igi != NULL, ("%s: no igmp_ifsoftc for ifp %p", __func__, ifp));
  728 
  729         if (igi->igi_flags & IGIF_LOOPBACK) {
  730                 CTR2(KTR_IGMPV3, "ignore v1 query on IGIF_LOOPBACK ifp %p(%s)",
  731                     ifp, ifp->if_xname);
  732                 goto out_locked;
  733         }
  734 
  735         /*
  736          * Switch to IGMPv1 host compatibility mode.
  737          */
  738         igmp_set_version(igi, IGMP_VERSION_1);
  739 
  740         CTR2(KTR_IGMPV3, "process v1 query on ifp %p(%s)", ifp, ifp->if_xname);
  741 
  742         /*
  743          * Start the timers in all of our group records
  744          * for the interface on which the query arrived,
  745          * except those which are already running.
  746          */
  747         IF_ADDR_RLOCK(ifp);
  748         TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
  749                 if (ifma->ifma_addr->sa_family != AF_INET ||
  750                     ifma->ifma_protospec == NULL)
  751                         continue;
  752                 inm = (struct in_multi *)ifma->ifma_protospec;
  753                 if (inm->inm_timer != 0)
  754                         continue;
  755                 switch (inm->inm_state) {
  756                 case IGMP_NOT_MEMBER:
  757                 case IGMP_SILENT_MEMBER:
  758                         break;
  759                 case IGMP_G_QUERY_PENDING_MEMBER:
  760                 case IGMP_SG_QUERY_PENDING_MEMBER:
  761                 case IGMP_REPORTING_MEMBER:
  762                 case IGMP_IDLE_MEMBER:
  763                 case IGMP_LAZY_MEMBER:
  764                 case IGMP_SLEEPING_MEMBER:
  765                 case IGMP_AWAKENING_MEMBER:
  766                         inm->inm_state = IGMP_REPORTING_MEMBER;
  767                         inm->inm_timer = IGMP_RANDOM_DELAY(
  768                             IGMP_V1V2_MAX_RI * PR_FASTHZ);
  769                         V_current_state_timers_running = 1;
  770                         break;
  771                 case IGMP_LEAVING_MEMBER:
  772                         break;
  773                 }
  774         }
  775         IF_ADDR_RUNLOCK(ifp);
  776 
  777 out_locked:
  778         IGMP_UNLOCK();
  779         IN_MULTI_UNLOCK();
  780 
  781         return (0);
  782 }
  783 
  784 /*
  785  * Process a received IGMPv2 general or group-specific query.
  786  */
  787 static int
  788 igmp_input_v2_query(struct ifnet *ifp, const struct ip *ip,
  789     const struct igmp *igmp)
  790 {
  791         struct ifmultiaddr      *ifma;
  792         struct igmp_ifsoftc     *igi;
  793         struct in_multi         *inm;
  794         int                      is_general_query;
  795         uint16_t                 timer;
  796 
  797         is_general_query = 0;
  798 
  799         /*
  800          * Validate address fields upfront.
  801          * XXX SMPng: unlocked increments in igmpstat assumed atomic.
  802          */
  803         if (in_nullhost(igmp->igmp_group)) {
  804                 /*
  805                  * IGMPv2 General Query.
  806                  * If this was not sent to the all-hosts group, ignore it.
  807                  */
  808                 if (!in_allhosts(ip->ip_dst))
  809                         return (0);
  810                 IGMPSTAT_INC(igps_rcv_gen_queries);
  811                 is_general_query = 1;
  812         } else {
  813                 /* IGMPv2 Group-Specific Query. */
  814                 IGMPSTAT_INC(igps_rcv_group_queries);
  815         }
  816 
  817         IN_MULTI_LOCK();
  818         IGMP_LOCK();
  819 
  820         igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
  821         KASSERT(igi != NULL, ("%s: no igmp_ifsoftc for ifp %p", __func__, ifp));
  822 
  823         if (igi->igi_flags & IGIF_LOOPBACK) {
  824                 CTR2(KTR_IGMPV3, "ignore v2 query on IGIF_LOOPBACK ifp %p(%s)",
  825                     ifp, ifp->if_xname);
  826                 goto out_locked;
  827         }
  828 
  829         /*
  830          * Ignore v2 query if in v1 Compatibility Mode.
  831          */
  832         if (igi->igi_version == IGMP_VERSION_1)
  833                 goto out_locked;
  834 
  835         igmp_set_version(igi, IGMP_VERSION_2);
  836 
  837         timer = igmp->igmp_code * PR_FASTHZ / IGMP_TIMER_SCALE;
  838         if (timer == 0)
  839                 timer = 1;
  840 
  841         if (is_general_query) {
  842                 /*
  843                  * For each reporting group joined on this
  844                  * interface, kick the report timer.
  845                  */
  846                 CTR2(KTR_IGMPV3, "process v2 general query on ifp %p(%s)",
  847                     ifp, ifp->if_xname);
  848                 IF_ADDR_RLOCK(ifp);
  849                 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
  850                         if (ifma->ifma_addr->sa_family != AF_INET ||
  851                             ifma->ifma_protospec == NULL)
  852                                 continue;
  853                         inm = (struct in_multi *)ifma->ifma_protospec;
  854                         igmp_v2_update_group(inm, timer);
  855                 }
  856                 IF_ADDR_RUNLOCK(ifp);
  857         } else {
  858                 /*
  859                  * Group-specific IGMPv2 query, we need only
  860                  * look up the single group to process it.
  861                  */
  862                 inm = inm_lookup(ifp, igmp->igmp_group);
  863                 if (inm != NULL) {
  864                         CTR3(KTR_IGMPV3,
  865                             "process v2 query 0x%08x on ifp %p(%s)",
  866                             ntohl(igmp->igmp_group.s_addr), ifp, ifp->if_xname);
  867                         igmp_v2_update_group(inm, timer);
  868                 }
  869         }
  870 
  871 out_locked:
  872         IGMP_UNLOCK();
  873         IN_MULTI_UNLOCK();
  874 
  875         return (0);
  876 }
  877 
  878 /*
  879  * Update the report timer on a group in response to an IGMPv2 query.
  880  *
  881  * If we are becoming the reporting member for this group, start the timer.
  882  * If we already are the reporting member for this group, and timer is
  883  * below the threshold, reset it.
  884  *
  885  * We may be updating the group for the first time since we switched
  886  * to IGMPv3. If we are, then we must clear any recorded source lists,
  887  * and transition to REPORTING state; the group timer is overloaded
  888  * for group and group-source query responses. 
  889  *
  890  * Unlike IGMPv3, the delay per group should be jittered
  891  * to avoid bursts of IGMPv2 reports.
  892  */
  893 static void
  894 igmp_v2_update_group(struct in_multi *inm, const int timer)
  895 {
  896 
  897         CTR4(KTR_IGMPV3, "0x%08x: %s/%s timer=%d", __func__,
  898             ntohl(inm->inm_addr.s_addr), inm->inm_ifp->if_xname, timer);
  899 
  900         IN_MULTI_LOCK_ASSERT();
  901 
  902         switch (inm->inm_state) {
  903         case IGMP_NOT_MEMBER:
  904         case IGMP_SILENT_MEMBER:
  905                 break;
  906         case IGMP_REPORTING_MEMBER:
  907                 if (inm->inm_timer != 0 &&
  908                     inm->inm_timer <= timer) {
  909                         CTR1(KTR_IGMPV3, "%s: REPORTING and timer running, "
  910                             "skipping.", __func__);
  911                         break;
  912                 }
  913                 /* FALLTHROUGH */
  914         case IGMP_SG_QUERY_PENDING_MEMBER:
  915         case IGMP_G_QUERY_PENDING_MEMBER:
  916         case IGMP_IDLE_MEMBER:
  917         case IGMP_LAZY_MEMBER:
  918         case IGMP_AWAKENING_MEMBER:
  919                 CTR1(KTR_IGMPV3, "%s: ->REPORTING", __func__);
  920                 inm->inm_state = IGMP_REPORTING_MEMBER;
  921                 inm->inm_timer = IGMP_RANDOM_DELAY(timer);
  922                 V_current_state_timers_running = 1;
  923                 break;
  924         case IGMP_SLEEPING_MEMBER:
  925                 CTR1(KTR_IGMPV3, "%s: ->AWAKENING", __func__);
  926                 inm->inm_state = IGMP_AWAKENING_MEMBER;
  927                 break;
  928         case IGMP_LEAVING_MEMBER:
  929                 break;
  930         }
  931 }
  932 
  933 /*
  934  * Process a received IGMPv3 general, group-specific or
  935  * group-and-source-specific query.
  936  * Assumes m has already been pulled up to the full IGMP message length.
  937  * Return 0 if successful, otherwise an appropriate error code is returned.
  938  */
  939 static int
  940 igmp_input_v3_query(struct ifnet *ifp, const struct ip *ip,
  941     /*const*/ struct igmpv3 *igmpv3)
  942 {
  943         struct igmp_ifsoftc     *igi;
  944         struct in_multi         *inm;
  945         int                      is_general_query;
  946         uint32_t                 maxresp, nsrc, qqi;
  947         uint16_t                 timer;
  948         uint8_t                  qrv;
  949 
  950         is_general_query = 0;
  951 
  952         CTR2(KTR_IGMPV3, "process v3 query on ifp %p(%s)", ifp, ifp->if_xname);
  953 
  954         maxresp = igmpv3->igmp_code;    /* in 1/10ths of a second */
  955         if (maxresp >= 128) {
  956                 maxresp = IGMP_MANT(igmpv3->igmp_code) <<
  957                           (IGMP_EXP(igmpv3->igmp_code) + 3);
  958         }
  959 
  960         /*
  961          * Robustness must never be less than 2 for on-wire IGMPv3.
  962          * FUTURE: Check if ifp has IGIF_LOOPBACK set, as we will make
  963          * an exception for interfaces whose IGMPv3 state changes
  964          * are redirected to loopback (e.g. MANET).
  965          */
  966         qrv = IGMP_QRV(igmpv3->igmp_misc);
  967         if (qrv < 2) {
  968                 CTR3(KTR_IGMPV3, "%s: clamping qrv %d to %d", __func__,
  969                     qrv, IGMP_RV_INIT);
  970                 qrv = IGMP_RV_INIT;
  971         }
  972 
  973         qqi = igmpv3->igmp_qqi;
  974         if (qqi >= 128) {
  975                 qqi = IGMP_MANT(igmpv3->igmp_qqi) <<
  976                      (IGMP_EXP(igmpv3->igmp_qqi) + 3);
  977         }
  978 
  979         timer = maxresp * PR_FASTHZ / IGMP_TIMER_SCALE;
  980         if (timer == 0)
  981                 timer = 1;
  982 
  983         nsrc = ntohs(igmpv3->igmp_numsrc);
  984 
  985         /*
  986          * Validate address fields and versions upfront before
  987          * accepting v3 query.
  988          * XXX SMPng: Unlocked access to igmpstat counters here.
  989          */
  990         if (in_nullhost(igmpv3->igmp_group)) {
  991                 /*
  992                  * IGMPv3 General Query.
  993                  *
  994                  * General Queries SHOULD be directed to 224.0.0.1.
  995                  * A general query with a source list has undefined
  996                  * behaviour; discard it.
  997                  */
  998                 IGMPSTAT_INC(igps_rcv_gen_queries);
  999                 if (!in_allhosts(ip->ip_dst) || nsrc > 0) {
 1000                         IGMPSTAT_INC(igps_rcv_badqueries);
 1001                         return (0);
 1002                 }
 1003                 is_general_query = 1;
 1004         } else {
 1005                 /* Group or group-source specific query. */
 1006                 if (nsrc == 0)
 1007                         IGMPSTAT_INC(igps_rcv_group_queries);
 1008                 else
 1009                         IGMPSTAT_INC(igps_rcv_gsr_queries);
 1010         }
 1011 
 1012         IN_MULTI_LOCK();
 1013         IGMP_LOCK();
 1014 
 1015         igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
 1016         KASSERT(igi != NULL, ("%s: no igmp_ifsoftc for ifp %p", __func__, ifp));
 1017 
 1018         if (igi->igi_flags & IGIF_LOOPBACK) {
 1019                 CTR2(KTR_IGMPV3, "ignore v3 query on IGIF_LOOPBACK ifp %p(%s)",
 1020                     ifp, ifp->if_xname);
 1021                 goto out_locked;
 1022         }
 1023 
 1024         /*
 1025          * Discard the v3 query if we're in Compatibility Mode.
 1026          * The RFC is not obviously worded that hosts need to stay in
 1027          * compatibility mode until the Old Version Querier Present
 1028          * timer expires.
 1029          */
 1030         if (igi->igi_version != IGMP_VERSION_3) {
 1031                 CTR3(KTR_IGMPV3, "ignore v3 query in v%d mode on ifp %p(%s)",
 1032                     igi->igi_version, ifp, ifp->if_xname);
 1033                 goto out_locked;
 1034         }
 1035 
 1036         igmp_set_version(igi, IGMP_VERSION_3);
 1037         igi->igi_rv = qrv;
 1038         igi->igi_qi = qqi;
 1039         igi->igi_qri = maxresp;
 1040 
 1041         CTR4(KTR_IGMPV3, "%s: qrv %d qi %d qri %d", __func__, qrv, qqi,
 1042             maxresp);
 1043 
 1044         if (is_general_query) {
 1045                 /*
 1046                  * Schedule a current-state report on this ifp for
 1047                  * all groups, possibly containing source lists.
 1048                  * If there is a pending General Query response
 1049                  * scheduled earlier than the selected delay, do
 1050                  * not schedule any other reports.
 1051                  * Otherwise, reset the interface timer.
 1052                  */
 1053                 CTR2(KTR_IGMPV3, "process v3 general query on ifp %p(%s)",
 1054                     ifp, ifp->if_xname);
 1055                 if (igi->igi_v3_timer == 0 || igi->igi_v3_timer >= timer) {
 1056                         igi->igi_v3_timer = IGMP_RANDOM_DELAY(timer);
 1057                         V_interface_timers_running = 1;
 1058                 }
 1059         } else {
 1060                 /*
 1061                  * Group-source-specific queries are throttled on
 1062                  * a per-group basis to defeat denial-of-service attempts.
 1063                  * Queries for groups we are not a member of on this
 1064                  * link are simply ignored.
 1065                  */
 1066                 inm = inm_lookup(ifp, igmpv3->igmp_group);
 1067                 if (inm == NULL)
 1068                         goto out_locked;
 1069                 if (nsrc > 0) {
 1070                         if (!ratecheck(&inm->inm_lastgsrtv,
 1071                             &V_igmp_gsrdelay)) {
 1072                                 CTR1(KTR_IGMPV3, "%s: GS query throttled.",
 1073                                     __func__);
 1074                                 IGMPSTAT_INC(igps_drop_gsr_queries);
 1075                                 goto out_locked;
 1076                         }
 1077                 }
 1078                 CTR3(KTR_IGMPV3, "process v3 0x%08x query on ifp %p(%s)",
 1079                      ntohl(igmpv3->igmp_group.s_addr), ifp, ifp->if_xname);
 1080                 /*
 1081                  * If there is a pending General Query response
 1082                  * scheduled sooner than the selected delay, no
 1083                  * further report need be scheduled.
 1084                  * Otherwise, prepare to respond to the
 1085                  * group-specific or group-and-source query.
 1086                  */
 1087                 if (igi->igi_v3_timer == 0 || igi->igi_v3_timer >= timer)
 1088                         igmp_input_v3_group_query(inm, igi, timer, igmpv3);
 1089         }
 1090 
 1091 out_locked:
 1092         IGMP_UNLOCK();
 1093         IN_MULTI_UNLOCK();
 1094 
 1095         return (0);
 1096 }
 1097 
 1098 /*
 1099  * Process a received IGMPv3 group-specific or group-and-source-specific
 1100  * query.
 1101  * Return <0 if any error occurred. Currently this is ignored.
 1102  */
 1103 static int
 1104 igmp_input_v3_group_query(struct in_multi *inm, struct igmp_ifsoftc *igi,
 1105     int timer, /*const*/ struct igmpv3 *igmpv3)
 1106 {
 1107         int                      retval;
 1108         uint16_t                 nsrc;
 1109 
 1110         IN_MULTI_LOCK_ASSERT();
 1111         IGMP_LOCK_ASSERT();
 1112 
 1113         retval = 0;
 1114 
 1115         switch (inm->inm_state) {
 1116         case IGMP_NOT_MEMBER:
 1117         case IGMP_SILENT_MEMBER:
 1118         case IGMP_SLEEPING_MEMBER:
 1119         case IGMP_LAZY_MEMBER:
 1120         case IGMP_AWAKENING_MEMBER:
 1121         case IGMP_IDLE_MEMBER:
 1122         case IGMP_LEAVING_MEMBER:
 1123                 return (retval);
 1124                 break;
 1125         case IGMP_REPORTING_MEMBER:
 1126         case IGMP_G_QUERY_PENDING_MEMBER:
 1127         case IGMP_SG_QUERY_PENDING_MEMBER:
 1128                 break;
 1129         }
 1130 
 1131         nsrc = ntohs(igmpv3->igmp_numsrc);
 1132 
 1133         /*
 1134          * Deal with group-specific queries upfront.
 1135          * If any group query is already pending, purge any recorded
 1136          * source-list state if it exists, and schedule a query response
 1137          * for this group-specific query.
 1138          */
 1139         if (nsrc == 0) {
 1140                 if (inm->inm_state == IGMP_G_QUERY_PENDING_MEMBER ||
 1141                     inm->inm_state == IGMP_SG_QUERY_PENDING_MEMBER) {
 1142                         inm_clear_recorded(inm);
 1143                         timer = min(inm->inm_timer, timer);
 1144                 }
 1145                 inm->inm_state = IGMP_G_QUERY_PENDING_MEMBER;
 1146                 inm->inm_timer = IGMP_RANDOM_DELAY(timer);
 1147                 V_current_state_timers_running = 1;
 1148                 return (retval);
 1149         }
 1150 
 1151         /*
 1152          * Deal with the case where a group-and-source-specific query has
 1153          * been received but a group-specific query is already pending.
 1154          */
 1155         if (inm->inm_state == IGMP_G_QUERY_PENDING_MEMBER) {
 1156                 timer = min(inm->inm_timer, timer);
 1157                 inm->inm_timer = IGMP_RANDOM_DELAY(timer);
 1158                 V_current_state_timers_running = 1;
 1159                 return (retval);
 1160         }
 1161 
 1162         /*
 1163          * Finally, deal with the case where a group-and-source-specific
 1164          * query has been received, where a response to a previous g-s-r
 1165          * query exists, or none exists.
 1166          * In this case, we need to parse the source-list which the Querier
 1167          * has provided us with and check if we have any source list filter
 1168          * entries at T1 for these sources. If we do not, there is no need
 1169          * schedule a report and the query may be dropped.
 1170          * If we do, we must record them and schedule a current-state
 1171          * report for those sources.
 1172          * FIXME: Handling source lists larger than 1 mbuf requires that
 1173          * we pass the mbuf chain pointer down to this function, and use
 1174          * m_getptr() to walk the chain.
 1175          */
 1176         if (inm->inm_nsrc > 0) {
 1177                 const struct in_addr    *ap;
 1178                 int                      i, nrecorded;
 1179 
 1180                 ap = (const struct in_addr *)(igmpv3 + 1);
 1181                 nrecorded = 0;
 1182                 for (i = 0; i < nsrc; i++, ap++) {
 1183                         retval = inm_record_source(inm, ap->s_addr);
 1184                         if (retval < 0)
 1185                                 break;
 1186                         nrecorded += retval;
 1187                 }
 1188                 if (nrecorded > 0) {
 1189                         CTR1(KTR_IGMPV3,
 1190                             "%s: schedule response to SG query", __func__);
 1191                         inm->inm_state = IGMP_SG_QUERY_PENDING_MEMBER;
 1192                         inm->inm_timer = IGMP_RANDOM_DELAY(timer);
 1193                         V_current_state_timers_running = 1;
 1194                 }
 1195         }
 1196 
 1197         return (retval);
 1198 }
 1199 
 1200 /*
 1201  * Process a received IGMPv1 host membership report.
 1202  *
 1203  * NOTE: 0.0.0.0 workaround breaks const correctness.
 1204  */
 1205 static int
 1206 igmp_input_v1_report(struct ifnet *ifp, /*const*/ struct ip *ip,
 1207     /*const*/ struct igmp *igmp)
 1208 {
 1209         struct rm_priotracker in_ifa_tracker;
 1210         struct in_ifaddr *ia;
 1211         struct in_multi *inm;
 1212 
 1213         IGMPSTAT_INC(igps_rcv_reports);
 1214 
 1215         if (ifp->if_flags & IFF_LOOPBACK)
 1216                 return (0);
 1217 
 1218         if (!IN_MULTICAST(ntohl(igmp->igmp_group.s_addr)) ||
 1219             !in_hosteq(igmp->igmp_group, ip->ip_dst)) {
 1220                 IGMPSTAT_INC(igps_rcv_badreports);
 1221                 return (EINVAL);
 1222         }
 1223 
 1224         /*
 1225          * RFC 3376, Section 4.2.13, 9.2, 9.3:
 1226          * Booting clients may use the source address 0.0.0.0. Some
 1227          * IGMP daemons may not know how to use IP_RECVIF to determine
 1228          * the interface upon which this message was received.
 1229          * Replace 0.0.0.0 with the subnet address if told to do so.
 1230          */
 1231         if (V_igmp_recvifkludge && in_nullhost(ip->ip_src)) {
 1232                 IFP_TO_IA(ifp, ia, &in_ifa_tracker);
 1233                 if (ia != NULL) {
 1234                         ip->ip_src.s_addr = htonl(ia->ia_subnet);
 1235                         ifa_free(&ia->ia_ifa);
 1236                 }
 1237         }
 1238 
 1239         CTR3(KTR_IGMPV3, "process v1 report 0x%08x on ifp %p(%s)",
 1240              ntohl(igmp->igmp_group.s_addr), ifp, ifp->if_xname);
 1241 
 1242         /*
 1243          * IGMPv1 report suppression.
 1244          * If we are a member of this group, and our membership should be
 1245          * reported, stop our group timer and transition to the 'lazy' state.
 1246          */
 1247         IN_MULTI_LOCK();
 1248         inm = inm_lookup(ifp, igmp->igmp_group);
 1249         if (inm != NULL) {
 1250                 struct igmp_ifsoftc *igi;
 1251 
 1252                 igi = inm->inm_igi;
 1253                 if (igi == NULL) {
 1254                         KASSERT(igi != NULL,
 1255                             ("%s: no igi for ifp %p", __func__, ifp));
 1256                         goto out_locked;
 1257                 }
 1258 
 1259                 IGMPSTAT_INC(igps_rcv_ourreports);
 1260 
 1261                 /*
 1262                  * If we are in IGMPv3 host mode, do not allow the
 1263                  * other host's IGMPv1 report to suppress our reports
 1264                  * unless explicitly configured to do so.
 1265                  */
 1266                 if (igi->igi_version == IGMP_VERSION_3) {
 1267                         if (V_igmp_legacysupp)
 1268                                 igmp_v3_suppress_group_record(inm);
 1269                         goto out_locked;
 1270                 }
 1271 
 1272                 inm->inm_timer = 0;
 1273 
 1274                 switch (inm->inm_state) {
 1275                 case IGMP_NOT_MEMBER:
 1276                 case IGMP_SILENT_MEMBER:
 1277                         break;
 1278                 case IGMP_IDLE_MEMBER:
 1279                 case IGMP_LAZY_MEMBER:
 1280                 case IGMP_AWAKENING_MEMBER:
 1281                         CTR3(KTR_IGMPV3,
 1282                             "report suppressed for 0x%08x on ifp %p(%s)",
 1283                             ntohl(igmp->igmp_group.s_addr), ifp,
 1284                             ifp->if_xname);
 1285                 case IGMP_SLEEPING_MEMBER:
 1286                         inm->inm_state = IGMP_SLEEPING_MEMBER;
 1287                         break;
 1288                 case IGMP_REPORTING_MEMBER:
 1289                         CTR3(KTR_IGMPV3,
 1290                             "report suppressed for 0x%08x on ifp %p(%s)",
 1291                             ntohl(igmp->igmp_group.s_addr), ifp,
 1292                             ifp->if_xname);
 1293                         if (igi->igi_version == IGMP_VERSION_1)
 1294                                 inm->inm_state = IGMP_LAZY_MEMBER;
 1295                         else if (igi->igi_version == IGMP_VERSION_2)
 1296                                 inm->inm_state = IGMP_SLEEPING_MEMBER;
 1297                         break;
 1298                 case IGMP_G_QUERY_PENDING_MEMBER:
 1299                 case IGMP_SG_QUERY_PENDING_MEMBER:
 1300                 case IGMP_LEAVING_MEMBER:
 1301                         break;
 1302                 }
 1303         }
 1304 
 1305 out_locked:
 1306         IN_MULTI_UNLOCK();
 1307 
 1308         return (0);
 1309 }
 1310 
 1311 /*
 1312  * Process a received IGMPv2 host membership report.
 1313  *
 1314  * NOTE: 0.0.0.0 workaround breaks const correctness.
 1315  */
 1316 static int
 1317 igmp_input_v2_report(struct ifnet *ifp, /*const*/ struct ip *ip,
 1318     /*const*/ struct igmp *igmp)
 1319 {
 1320         struct rm_priotracker in_ifa_tracker;
 1321         struct in_ifaddr *ia;
 1322         struct in_multi *inm;
 1323 
 1324         /*
 1325          * Make sure we don't hear our own membership report.  Fast
 1326          * leave requires knowing that we are the only member of a
 1327          * group.
 1328          */
 1329         IFP_TO_IA(ifp, ia, &in_ifa_tracker);
 1330         if (ia != NULL && in_hosteq(ip->ip_src, IA_SIN(ia)->sin_addr)) {
 1331                 ifa_free(&ia->ia_ifa);
 1332                 return (0);
 1333         }
 1334 
 1335         IGMPSTAT_INC(igps_rcv_reports);
 1336 
 1337         if (ifp->if_flags & IFF_LOOPBACK) {
 1338                 if (ia != NULL)
 1339                         ifa_free(&ia->ia_ifa);
 1340                 return (0);
 1341         }
 1342 
 1343         if (!IN_MULTICAST(ntohl(igmp->igmp_group.s_addr)) ||
 1344             !in_hosteq(igmp->igmp_group, ip->ip_dst)) {
 1345                 if (ia != NULL)
 1346                         ifa_free(&ia->ia_ifa);
 1347                 IGMPSTAT_INC(igps_rcv_badreports);
 1348                 return (EINVAL);
 1349         }
 1350 
 1351         /*
 1352          * RFC 3376, Section 4.2.13, 9.2, 9.3:
 1353          * Booting clients may use the source address 0.0.0.0. Some
 1354          * IGMP daemons may not know how to use IP_RECVIF to determine
 1355          * the interface upon which this message was received.
 1356          * Replace 0.0.0.0 with the subnet address if told to do so.
 1357          */
 1358         if (V_igmp_recvifkludge && in_nullhost(ip->ip_src)) {
 1359                 if (ia != NULL)
 1360                         ip->ip_src.s_addr = htonl(ia->ia_subnet);
 1361         }
 1362         if (ia != NULL)
 1363                 ifa_free(&ia->ia_ifa);
 1364 
 1365         CTR3(KTR_IGMPV3, "process v2 report 0x%08x on ifp %p(%s)",
 1366              ntohl(igmp->igmp_group.s_addr), ifp, ifp->if_xname);
 1367 
 1368         /*
 1369          * IGMPv2 report suppression.
 1370          * If we are a member of this group, and our membership should be
 1371          * reported, and our group timer is pending or about to be reset,
 1372          * stop our group timer by transitioning to the 'lazy' state.
 1373          */
 1374         IN_MULTI_LOCK();
 1375         inm = inm_lookup(ifp, igmp->igmp_group);
 1376         if (inm != NULL) {
 1377                 struct igmp_ifsoftc *igi;
 1378 
 1379                 igi = inm->inm_igi;
 1380                 KASSERT(igi != NULL, ("%s: no igi for ifp %p", __func__, ifp));
 1381 
 1382                 IGMPSTAT_INC(igps_rcv_ourreports);
 1383 
 1384                 /*
 1385                  * If we are in IGMPv3 host mode, do not allow the
 1386                  * other host's IGMPv1 report to suppress our reports
 1387                  * unless explicitly configured to do so.
 1388                  */
 1389                 if (igi->igi_version == IGMP_VERSION_3) {
 1390                         if (V_igmp_legacysupp)
 1391                                 igmp_v3_suppress_group_record(inm);
 1392                         goto out_locked;
 1393                 }
 1394 
 1395                 inm->inm_timer = 0;
 1396 
 1397                 switch (inm->inm_state) {
 1398                 case IGMP_NOT_MEMBER:
 1399                 case IGMP_SILENT_MEMBER:
 1400                 case IGMP_SLEEPING_MEMBER:
 1401                         break;
 1402                 case IGMP_REPORTING_MEMBER:
 1403                 case IGMP_IDLE_MEMBER:
 1404                 case IGMP_AWAKENING_MEMBER:
 1405                         CTR3(KTR_IGMPV3,
 1406                             "report suppressed for 0x%08x on ifp %p(%s)",
 1407                             ntohl(igmp->igmp_group.s_addr), ifp, ifp->if_xname);
 1408                 case IGMP_LAZY_MEMBER:
 1409                         inm->inm_state = IGMP_LAZY_MEMBER;
 1410                         break;
 1411                 case IGMP_G_QUERY_PENDING_MEMBER:
 1412                 case IGMP_SG_QUERY_PENDING_MEMBER:
 1413                 case IGMP_LEAVING_MEMBER:
 1414                         break;
 1415                 }
 1416         }
 1417 
 1418 out_locked:
 1419         IN_MULTI_UNLOCK();
 1420 
 1421         return (0);
 1422 }
 1423 
 1424 int
 1425 igmp_input(struct mbuf **mp, int *offp, int proto)
 1426 {
 1427         int iphlen;
 1428         struct ifnet *ifp;
 1429         struct igmp *igmp;
 1430         struct ip *ip;
 1431         struct mbuf *m;
 1432         int igmplen;
 1433         int minlen;
 1434         int queryver;
 1435 
 1436         CTR3(KTR_IGMPV3, "%s: called w/mbuf (%p,%d)", __func__, *mp, *offp);
 1437 
 1438         m = *mp;
 1439         ifp = m->m_pkthdr.rcvif;
 1440         *mp = NULL;
 1441 
 1442         IGMPSTAT_INC(igps_rcv_total);
 1443 
 1444         ip = mtod(m, struct ip *);
 1445         iphlen = *offp;
 1446         igmplen = ntohs(ip->ip_len) - iphlen;
 1447 
 1448         /*
 1449          * Validate lengths.
 1450          */
 1451         if (igmplen < IGMP_MINLEN) {
 1452                 IGMPSTAT_INC(igps_rcv_tooshort);
 1453                 m_freem(m);
 1454                 return (IPPROTO_DONE);
 1455         }
 1456 
 1457         /*
 1458          * Always pullup to the minimum size for v1/v2 or v3
 1459          * to amortize calls to m_pullup().
 1460          */
 1461         minlen = iphlen;
 1462         if (igmplen >= IGMP_V3_QUERY_MINLEN)
 1463                 minlen += IGMP_V3_QUERY_MINLEN;
 1464         else
 1465                 minlen += IGMP_MINLEN;
 1466         if ((!M_WRITABLE(m) || m->m_len < minlen) &&
 1467             (m = m_pullup(m, minlen)) == NULL) {
 1468                 IGMPSTAT_INC(igps_rcv_tooshort);
 1469                 return (IPPROTO_DONE);
 1470         }
 1471         ip = mtod(m, struct ip *);
 1472 
 1473         /*
 1474          * Validate checksum.
 1475          */
 1476         m->m_data += iphlen;
 1477         m->m_len -= iphlen;
 1478         igmp = mtod(m, struct igmp *);
 1479         if (in_cksum(m, igmplen)) {
 1480                 IGMPSTAT_INC(igps_rcv_badsum);
 1481                 m_freem(m);
 1482                 return (IPPROTO_DONE);
 1483         }
 1484         m->m_data -= iphlen;
 1485         m->m_len += iphlen;
 1486 
 1487         /*
 1488          * IGMP control traffic is link-scope, and must have a TTL of 1.
 1489          * DVMRP traffic (e.g. mrinfo, mtrace) is an exception;
 1490          * probe packets may come from beyond the LAN.
 1491          */
 1492         if (igmp->igmp_type != IGMP_DVMRP && ip->ip_ttl != 1) {
 1493                 IGMPSTAT_INC(igps_rcv_badttl);
 1494                 m_freem(m);
 1495                 return (IPPROTO_DONE);
 1496         }
 1497 
 1498         switch (igmp->igmp_type) {
 1499         case IGMP_HOST_MEMBERSHIP_QUERY:
 1500                 if (igmplen == IGMP_MINLEN) {
 1501                         if (igmp->igmp_code == 0)
 1502                                 queryver = IGMP_VERSION_1;
 1503                         else
 1504                                 queryver = IGMP_VERSION_2;
 1505                 } else if (igmplen >= IGMP_V3_QUERY_MINLEN) {
 1506                         queryver = IGMP_VERSION_3;
 1507                 } else {
 1508                         IGMPSTAT_INC(igps_rcv_tooshort);
 1509                         m_freem(m);
 1510                         return (IPPROTO_DONE);
 1511                 }
 1512 
 1513                 switch (queryver) {
 1514                 case IGMP_VERSION_1:
 1515                         IGMPSTAT_INC(igps_rcv_v1v2_queries);
 1516                         if (!V_igmp_v1enable)
 1517                                 break;
 1518                         if (igmp_input_v1_query(ifp, ip, igmp) != 0) {
 1519                                 m_freem(m);
 1520                                 return (IPPROTO_DONE);
 1521                         }
 1522                         break;
 1523 
 1524                 case IGMP_VERSION_2:
 1525                         IGMPSTAT_INC(igps_rcv_v1v2_queries);
 1526                         if (!V_igmp_v2enable)
 1527                                 break;
 1528                         if (igmp_input_v2_query(ifp, ip, igmp) != 0) {
 1529                                 m_freem(m);
 1530                                 return (IPPROTO_DONE);
 1531                         }
 1532                         break;
 1533 
 1534                 case IGMP_VERSION_3: {
 1535                                 struct igmpv3 *igmpv3;
 1536                                 uint16_t igmpv3len;
 1537                                 uint16_t nsrc;
 1538 
 1539                                 IGMPSTAT_INC(igps_rcv_v3_queries);
 1540                                 igmpv3 = (struct igmpv3 *)igmp;
 1541                                 /*
 1542                                  * Validate length based on source count.
 1543                                  */
 1544                                 nsrc = ntohs(igmpv3->igmp_numsrc);
 1545                                 if (nsrc * sizeof(in_addr_t) >
 1546                                     UINT16_MAX - iphlen - IGMP_V3_QUERY_MINLEN) {
 1547                                         IGMPSTAT_INC(igps_rcv_tooshort);
 1548                                         return (IPPROTO_DONE);
 1549                                 }
 1550                                 /*
 1551                                  * m_pullup() may modify m, so pullup in
 1552                                  * this scope.
 1553                                  */
 1554                                 igmpv3len = iphlen + IGMP_V3_QUERY_MINLEN +
 1555                                    sizeof(struct in_addr) * nsrc;
 1556                                 if ((!M_WRITABLE(m) ||
 1557                                      m->m_len < igmpv3len) &&
 1558                                     (m = m_pullup(m, igmpv3len)) == NULL) {
 1559                                         IGMPSTAT_INC(igps_rcv_tooshort);
 1560                                         return (IPPROTO_DONE);
 1561                                 }
 1562                                 igmpv3 = (struct igmpv3 *)(mtod(m, uint8_t *)
 1563                                     + iphlen);
 1564                                 if (igmp_input_v3_query(ifp, ip, igmpv3) != 0) {
 1565                                         m_freem(m);
 1566                                         return (IPPROTO_DONE);
 1567                                 }
 1568                         }
 1569                         break;
 1570                 }
 1571                 break;
 1572 
 1573         case IGMP_v1_HOST_MEMBERSHIP_REPORT:
 1574                 if (!V_igmp_v1enable)
 1575                         break;
 1576                 if (igmp_input_v1_report(ifp, ip, igmp) != 0) {
 1577                         m_freem(m);
 1578                         return (IPPROTO_DONE);
 1579                 }
 1580                 break;
 1581 
 1582         case IGMP_v2_HOST_MEMBERSHIP_REPORT:
 1583                 if (!V_igmp_v2enable)
 1584                         break;
 1585                 if (!ip_checkrouteralert(m))
 1586                         IGMPSTAT_INC(igps_rcv_nora);
 1587                 if (igmp_input_v2_report(ifp, ip, igmp) != 0) {
 1588                         m_freem(m);
 1589                         return (IPPROTO_DONE);
 1590                 }
 1591                 break;
 1592 
 1593         case IGMP_v3_HOST_MEMBERSHIP_REPORT:
 1594                 /*
 1595                  * Hosts do not need to process IGMPv3 membership reports,
 1596                  * as report suppression is no longer required.
 1597                  */
 1598                 if (!ip_checkrouteralert(m))
 1599                         IGMPSTAT_INC(igps_rcv_nora);
 1600                 break;
 1601 
 1602         default:
 1603                 break;
 1604         }
 1605 
 1606         /*
 1607          * Pass all valid IGMP packets up to any process(es) listening on a
 1608          * raw IGMP socket.
 1609          */
 1610         *mp = m;
 1611         return (rip_input(mp, offp, proto));
 1612 }
 1613 
 1614 
 1615 /*
 1616  * Fast timeout handler (global).
 1617  * VIMAGE: Timeout handlers are expected to service all vimages.
 1618  */
 1619 void
 1620 igmp_fasttimo(void)
 1621 {
 1622         VNET_ITERATOR_DECL(vnet_iter);
 1623 
 1624         VNET_LIST_RLOCK_NOSLEEP();
 1625         VNET_FOREACH(vnet_iter) {
 1626                 CURVNET_SET(vnet_iter);
 1627                 igmp_fasttimo_vnet();
 1628                 CURVNET_RESTORE();
 1629         }
 1630         VNET_LIST_RUNLOCK_NOSLEEP();
 1631 }
 1632 
 1633 /*
 1634  * Fast timeout handler (per-vnet).
 1635  * Sends are shuffled off to a netisr to deal with Giant.
 1636  *
 1637  * VIMAGE: Assume caller has set up our curvnet.
 1638  */
 1639 static void
 1640 igmp_fasttimo_vnet(void)
 1641 {
 1642         struct mbufq             scq;   /* State-change packets */
 1643         struct mbufq             qrq;   /* Query response packets */
 1644         struct ifnet            *ifp;
 1645         struct igmp_ifsoftc     *igi;
 1646         struct ifmultiaddr      *ifma;
 1647         struct in_multi         *inm;
 1648         int                      loop, uri_fasthz;
 1649 
 1650         loop = 0;
 1651         uri_fasthz = 0;
 1652 
 1653         /*
 1654          * Quick check to see if any work needs to be done, in order to
 1655          * minimize the overhead of fasttimo processing.
 1656          * SMPng: XXX Unlocked reads.
 1657          */
 1658         if (!V_current_state_timers_running &&
 1659             !V_interface_timers_running &&
 1660             !V_state_change_timers_running)
 1661                 return;
 1662 
 1663         IN_MULTI_LOCK();
 1664         IGMP_LOCK();
 1665 
 1666         /*
 1667          * IGMPv3 General Query response timer processing.
 1668          */
 1669         if (V_interface_timers_running) {
 1670                 CTR1(KTR_IGMPV3, "%s: interface timers running", __func__);
 1671 
 1672                 V_interface_timers_running = 0;
 1673                 LIST_FOREACH(igi, &V_igi_head, igi_link) {
 1674                         if (igi->igi_v3_timer == 0) {
 1675                                 /* Do nothing. */
 1676                         } else if (--igi->igi_v3_timer == 0) {
 1677                                 igmp_v3_dispatch_general_query(igi);
 1678                         } else {
 1679                                 V_interface_timers_running = 1;
 1680                         }
 1681                 }
 1682         }
 1683 
 1684         if (!V_current_state_timers_running &&
 1685             !V_state_change_timers_running)
 1686                 goto out_locked;
 1687 
 1688         V_current_state_timers_running = 0;
 1689         V_state_change_timers_running = 0;
 1690 
 1691         CTR1(KTR_IGMPV3, "%s: state change timers running", __func__);
 1692 
 1693         /*
 1694          * IGMPv1/v2/v3 host report and state-change timer processing.
 1695          * Note: Processing a v3 group timer may remove a node.
 1696          */
 1697         LIST_FOREACH(igi, &V_igi_head, igi_link) {
 1698                 ifp = igi->igi_ifp;
 1699 
 1700                 if (igi->igi_version == IGMP_VERSION_3) {
 1701                         loop = (igi->igi_flags & IGIF_LOOPBACK) ? 1 : 0;
 1702                         uri_fasthz = IGMP_RANDOM_DELAY(igi->igi_uri *
 1703                             PR_FASTHZ);
 1704                         mbufq_init(&qrq, IGMP_MAX_G_GS_PACKETS);
 1705                         mbufq_init(&scq, IGMP_MAX_STATE_CHANGE_PACKETS);
 1706                 }
 1707 
 1708                 IF_ADDR_RLOCK(ifp);
 1709                 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
 1710                         if (ifma->ifma_addr->sa_family != AF_INET ||
 1711                             ifma->ifma_protospec == NULL)
 1712                                 continue;
 1713                         inm = (struct in_multi *)ifma->ifma_protospec;
 1714                         switch (igi->igi_version) {
 1715                         case IGMP_VERSION_1:
 1716                         case IGMP_VERSION_2:
 1717                                 igmp_v1v2_process_group_timer(inm,
 1718                                     igi->igi_version);
 1719                                 break;
 1720                         case IGMP_VERSION_3:
 1721                                 igmp_v3_process_group_timers(igi, &qrq,
 1722                                     &scq, inm, uri_fasthz);
 1723                                 break;
 1724                         }
 1725                 }
 1726                 IF_ADDR_RUNLOCK(ifp);
 1727 
 1728                 if (igi->igi_version == IGMP_VERSION_3) {
 1729                         struct in_multi         *tinm;
 1730 
 1731                         igmp_dispatch_queue(&qrq, 0, loop);
 1732                         igmp_dispatch_queue(&scq, 0, loop);
 1733 
 1734                         /*
 1735                          * Free the in_multi reference(s) for this
 1736                          * IGMP lifecycle.
 1737                          */
 1738                         SLIST_FOREACH_SAFE(inm, &igi->igi_relinmhead,
 1739                             inm_nrele, tinm) {
 1740                                 SLIST_REMOVE_HEAD(&igi->igi_relinmhead,
 1741                                     inm_nrele);
 1742                                 inm_release_locked(inm);
 1743                         }
 1744                 }
 1745         }
 1746 
 1747 out_locked:
 1748         IGMP_UNLOCK();
 1749         IN_MULTI_UNLOCK();
 1750 }
 1751 
 1752 /*
 1753  * Update host report group timer for IGMPv1/v2.
 1754  * Will update the global pending timer flags.
 1755  */
 1756 static void
 1757 igmp_v1v2_process_group_timer(struct in_multi *inm, const int version)
 1758 {
 1759         int report_timer_expired;
 1760 
 1761         IN_MULTI_LOCK_ASSERT();
 1762         IGMP_LOCK_ASSERT();
 1763 
 1764         if (inm->inm_timer == 0) {
 1765                 report_timer_expired = 0;
 1766         } else if (--inm->inm_timer == 0) {
 1767                 report_timer_expired = 1;
 1768         } else {
 1769                 V_current_state_timers_running = 1;
 1770                 return;
 1771         }
 1772 
 1773         switch (inm->inm_state) {
 1774         case IGMP_NOT_MEMBER:
 1775         case IGMP_SILENT_MEMBER:
 1776         case IGMP_IDLE_MEMBER:
 1777         case IGMP_LAZY_MEMBER:
 1778         case IGMP_SLEEPING_MEMBER:
 1779         case IGMP_AWAKENING_MEMBER:
 1780                 break;
 1781         case IGMP_REPORTING_MEMBER:
 1782                 if (report_timer_expired) {
 1783                         inm->inm_state = IGMP_IDLE_MEMBER;
 1784                         (void)igmp_v1v2_queue_report(inm,
 1785                             (version == IGMP_VERSION_2) ?
 1786                              IGMP_v2_HOST_MEMBERSHIP_REPORT :
 1787                              IGMP_v1_HOST_MEMBERSHIP_REPORT);
 1788                 }
 1789                 break;
 1790         case IGMP_G_QUERY_PENDING_MEMBER:
 1791         case IGMP_SG_QUERY_PENDING_MEMBER:
 1792         case IGMP_LEAVING_MEMBER:
 1793                 break;
 1794         }
 1795 }
 1796 
 1797 /*
 1798  * Update a group's timers for IGMPv3.
 1799  * Will update the global pending timer flags.
 1800  * Note: Unlocked read from igi.
 1801  */
 1802 static void
 1803 igmp_v3_process_group_timers(struct igmp_ifsoftc *igi,
 1804     struct mbufq *qrq, struct mbufq *scq,
 1805     struct in_multi *inm, const int uri_fasthz)
 1806 {
 1807         int query_response_timer_expired;
 1808         int state_change_retransmit_timer_expired;
 1809 
 1810         IN_MULTI_LOCK_ASSERT();
 1811         IGMP_LOCK_ASSERT();
 1812 
 1813         query_response_timer_expired = 0;
 1814         state_change_retransmit_timer_expired = 0;
 1815 
 1816         /*
 1817          * During a transition from v1/v2 compatibility mode back to v3,
 1818          * a group record in REPORTING state may still have its group
 1819          * timer active. This is a no-op in this function; it is easier
 1820          * to deal with it here than to complicate the slow-timeout path.
 1821          */
 1822         if (inm->inm_timer == 0) {
 1823                 query_response_timer_expired = 0;
 1824         } else if (--inm->inm_timer == 0) {
 1825                 query_response_timer_expired = 1;
 1826         } else {
 1827                 V_current_state_timers_running = 1;
 1828         }
 1829 
 1830         if (inm->inm_sctimer == 0) {
 1831                 state_change_retransmit_timer_expired = 0;
 1832         } else if (--inm->inm_sctimer == 0) {
 1833                 state_change_retransmit_timer_expired = 1;
 1834         } else {
 1835                 V_state_change_timers_running = 1;
 1836         }
 1837 
 1838         /* We are in fasttimo, so be quick about it. */
 1839         if (!state_change_retransmit_timer_expired &&
 1840             !query_response_timer_expired)
 1841                 return;
 1842 
 1843         switch (inm->inm_state) {
 1844         case IGMP_NOT_MEMBER:
 1845         case IGMP_SILENT_MEMBER:
 1846         case IGMP_SLEEPING_MEMBER:
 1847         case IGMP_LAZY_MEMBER:
 1848         case IGMP_AWAKENING_MEMBER:
 1849         case IGMP_IDLE_MEMBER:
 1850                 break;
 1851         case IGMP_G_QUERY_PENDING_MEMBER:
 1852         case IGMP_SG_QUERY_PENDING_MEMBER:
 1853                 /*
 1854                  * Respond to a previously pending Group-Specific
 1855                  * or Group-and-Source-Specific query by enqueueing
 1856                  * the appropriate Current-State report for
 1857                  * immediate transmission.
 1858                  */
 1859                 if (query_response_timer_expired) {
 1860                         int retval;
 1861 
 1862                         retval = igmp_v3_enqueue_group_record(qrq, inm, 0, 1,
 1863                             (inm->inm_state == IGMP_SG_QUERY_PENDING_MEMBER));
 1864                         CTR2(KTR_IGMPV3, "%s: enqueue record = %d",
 1865                             __func__, retval);
 1866                         inm->inm_state = IGMP_REPORTING_MEMBER;
 1867                         /* XXX Clear recorded sources for next time. */
 1868                         inm_clear_recorded(inm);
 1869                 }
 1870                 /* FALLTHROUGH */
 1871         case IGMP_REPORTING_MEMBER:
 1872         case IGMP_LEAVING_MEMBER:
 1873                 if (state_change_retransmit_timer_expired) {
 1874                         /*
 1875                          * State-change retransmission timer fired.
 1876                          * If there are any further pending retransmissions,
 1877                          * set the global pending state-change flag, and
 1878                          * reset the timer.
 1879                          */
 1880                         if (--inm->inm_scrv > 0) {
 1881                                 inm->inm_sctimer = uri_fasthz;
 1882                                 V_state_change_timers_running = 1;
 1883                         }
 1884                         /*
 1885                          * Retransmit the previously computed state-change
 1886                          * report. If there are no further pending
 1887                          * retransmissions, the mbuf queue will be consumed.
 1888                          * Update T0 state to T1 as we have now sent
 1889                          * a state-change.
 1890                          */
 1891                         (void)igmp_v3_merge_state_changes(inm, scq);
 1892 
 1893                         inm_commit(inm);
 1894                         CTR3(KTR_IGMPV3, "%s: T1 -> T0 for 0x%08x/%s", __func__,
 1895                             ntohl(inm->inm_addr.s_addr),
 1896                             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_ifsoftc *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_ifsoftc *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                 mbufq_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_ifsoftc *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                                 igmp_v3_cancel_link_timers(igi);
 2123                         }
 2124                 }
 2125         } else if (igi->igi_v1_timer > 0) {
 2126                 /*
 2127                  * IGMPv1 Querier Present timer running.
 2128                  * Stop IGMPv2 timer if running.
 2129                  *
 2130                  * If IGMPv1 was disabled since last timeout,
 2131                  * revert to IGMPv3.
 2132                  * If IGMPv1 is enabled, reset IGMPv2 timer if running.
 2133                  */
 2134                 if (!V_igmp_v1enable) {
 2135                         CTR5(KTR_IGMPV3,
 2136                             "%s: transition from v%d -> v%d on %p(%s)",
 2137                             __func__, igi->igi_version, IGMP_VERSION_3,
 2138                             igi->igi_ifp, igi->igi_ifp->if_xname);
 2139                         igi->igi_v1_timer = 0;
 2140                         igi->igi_version = IGMP_VERSION_3;
 2141                 } else {
 2142                         --igi->igi_v1_timer;
 2143                 }
 2144                 if (igi->igi_v2_timer > 0) {
 2145                         CTR3(KTR_IGMPV3,
 2146                             "%s: cancel v2 timer on %p(%s)",
 2147                             __func__, igi->igi_ifp, igi->igi_ifp->if_xname);
 2148                         igi->igi_v2_timer = 0;
 2149                 }
 2150         }
 2151 }
 2152 
 2153 /*
 2154  * Global slowtimo handler.
 2155  * VIMAGE: Timeout handlers are expected to service all vimages.
 2156  */
 2157 void
 2158 igmp_slowtimo(void)
 2159 {
 2160         VNET_ITERATOR_DECL(vnet_iter);
 2161 
 2162         VNET_LIST_RLOCK_NOSLEEP();
 2163         VNET_FOREACH(vnet_iter) {
 2164                 CURVNET_SET(vnet_iter);
 2165                 igmp_slowtimo_vnet();
 2166                 CURVNET_RESTORE();
 2167         }
 2168         VNET_LIST_RUNLOCK_NOSLEEP();
 2169 }
 2170 
 2171 /*
 2172  * Per-vnet slowtimo handler.
 2173  */
 2174 static void
 2175 igmp_slowtimo_vnet(void)
 2176 {
 2177         struct igmp_ifsoftc *igi;
 2178 
 2179         IGMP_LOCK();
 2180 
 2181         LIST_FOREACH(igi, &V_igi_head, igi_link) {
 2182                 igmp_v1v2_process_querier_timers(igi);
 2183         }
 2184 
 2185         IGMP_UNLOCK();
 2186 }
 2187 
 2188 /*
 2189  * Dispatch an IGMPv1/v2 host report or leave message.
 2190  * These are always small enough to fit inside a single mbuf.
 2191  */
 2192 static int
 2193 igmp_v1v2_queue_report(struct in_multi *inm, const int type)
 2194 {
 2195         struct ifnet            *ifp;
 2196         struct igmp             *igmp;
 2197         struct ip               *ip;
 2198         struct mbuf             *m;
 2199 
 2200         IN_MULTI_LOCK_ASSERT();
 2201         IGMP_LOCK_ASSERT();
 2202 
 2203         ifp = inm->inm_ifp;
 2204 
 2205         m = m_gethdr(M_NOWAIT, MT_DATA);
 2206         if (m == NULL)
 2207                 return (ENOMEM);
 2208         M_ALIGN(m, sizeof(struct ip) + sizeof(struct igmp));
 2209 
 2210         m->m_pkthdr.len = sizeof(struct ip) + sizeof(struct igmp);
 2211 
 2212         m->m_data += sizeof(struct ip);
 2213         m->m_len = sizeof(struct igmp);
 2214 
 2215         igmp = mtod(m, struct igmp *);
 2216         igmp->igmp_type = type;
 2217         igmp->igmp_code = 0;
 2218         igmp->igmp_group = inm->inm_addr;
 2219         igmp->igmp_cksum = 0;
 2220         igmp->igmp_cksum = in_cksum(m, sizeof(struct igmp));
 2221 
 2222         m->m_data -= sizeof(struct ip);
 2223         m->m_len += sizeof(struct ip);
 2224 
 2225         ip = mtod(m, struct ip *);
 2226         ip->ip_tos = 0;
 2227         ip->ip_len = htons(sizeof(struct ip) + sizeof(struct igmp));
 2228         ip->ip_off = 0;
 2229         ip->ip_p = IPPROTO_IGMP;
 2230         ip->ip_src.s_addr = INADDR_ANY;
 2231 
 2232         if (type == IGMP_HOST_LEAVE_MESSAGE)
 2233                 ip->ip_dst.s_addr = htonl(INADDR_ALLRTRS_GROUP);
 2234         else
 2235                 ip->ip_dst = inm->inm_addr;
 2236 
 2237         igmp_save_context(m, ifp);
 2238 
 2239         m->m_flags |= M_IGMPV2;
 2240         if (inm->inm_igi->igi_flags & IGIF_LOOPBACK)
 2241                 m->m_flags |= M_IGMP_LOOP;
 2242 
 2243         CTR2(KTR_IGMPV3, "%s: netisr_dispatch(NETISR_IGMP, %p)", __func__, m);
 2244         netisr_dispatch(NETISR_IGMP, m);
 2245 
 2246         return (0);
 2247 }
 2248 
 2249 /*
 2250  * Process a state change from the upper layer for the given IPv4 group.
 2251  *
 2252  * Each socket holds a reference on the in_multi in its own ip_moptions.
 2253  * The socket layer will have made the necessary updates to.the group
 2254  * state, it is now up to IGMP to issue a state change report if there
 2255  * has been any change between T0 (when the last state-change was issued)
 2256  * and T1 (now).
 2257  *
 2258  * We use the IGMPv3 state machine at group level. The IGMP module
 2259  * however makes the decision as to which IGMP protocol version to speak.
 2260  * A state change *from* INCLUDE {} always means an initial join.
 2261  * A state change *to* INCLUDE {} always means a final leave.
 2262  *
 2263  * FUTURE: If IGIF_V3LITE is enabled for this interface, then we can
 2264  * save ourselves a bunch of work; any exclusive mode groups need not
 2265  * compute source filter lists.
 2266  *
 2267  * VIMAGE: curvnet should have been set by caller, as this routine
 2268  * is called from the socket option handlers.
 2269  */
 2270 int
 2271 igmp_change_state(struct in_multi *inm)
 2272 {
 2273         struct igmp_ifsoftc *igi;
 2274         struct ifnet *ifp;
 2275         int error;
 2276 
 2277         IN_MULTI_LOCK_ASSERT();
 2278 
 2279         error = 0;
 2280 
 2281         /*
 2282          * Try to detect if the upper layer just asked us to change state
 2283          * for an interface which has now gone away.
 2284          */
 2285         KASSERT(inm->inm_ifma != NULL, ("%s: no ifma", __func__));
 2286         ifp = inm->inm_ifma->ifma_ifp;
 2287         /*
 2288          * Sanity check that netinet's notion of ifp is the
 2289          * same as net's.
 2290          */
 2291         KASSERT(inm->inm_ifp == ifp, ("%s: bad ifp", __func__));
 2292 
 2293         IGMP_LOCK();
 2294 
 2295         igi = ((struct in_ifinfo *)ifp->if_afdata[AF_INET])->ii_igmp;
 2296         KASSERT(igi != NULL, ("%s: no igmp_ifsoftc for ifp %p", __func__, ifp));
 2297 
 2298         /*
 2299          * If we detect a state transition to or from MCAST_UNDEFINED
 2300          * for this group, then we are starting or finishing an IGMP
 2301          * life cycle for this group.
 2302          */
 2303         if (inm->inm_st[1].iss_fmode != inm->inm_st[0].iss_fmode) {
 2304                 CTR3(KTR_IGMPV3, "%s: inm transition %d -> %d", __func__,
 2305                     inm->inm_st[0].iss_fmode, inm->inm_st[1].iss_fmode);
 2306                 if (inm->inm_st[0].iss_fmode == MCAST_UNDEFINED) {
 2307                         CTR1(KTR_IGMPV3, "%s: initial join", __func__);
 2308                         error = igmp_initial_join(inm, igi);
 2309                         goto out_locked;
 2310                 } else if (inm->inm_st[1].iss_fmode == MCAST_UNDEFINED) {
 2311                         CTR1(KTR_IGMPV3, "%s: final leave", __func__);
 2312                         igmp_final_leave(inm, igi);
 2313                         goto out_locked;
 2314                 }
 2315         } else {
 2316                 CTR1(KTR_IGMPV3, "%s: filter set change", __func__);
 2317         }
 2318 
 2319         error = igmp_handle_state_change(inm, igi);
 2320 
 2321 out_locked:
 2322         IGMP_UNLOCK();
 2323         return (error);
 2324 }
 2325 
 2326 /*
 2327  * Perform the initial join for an IGMP group.
 2328  *
 2329  * When joining a group:
 2330  *  If the group should have its IGMP traffic suppressed, do nothing.
 2331  *  IGMPv1 starts sending IGMPv1 host membership reports.
 2332  *  IGMPv2 starts sending IGMPv2 host membership reports.
 2333  *  IGMPv3 will schedule an IGMPv3 state-change report containing the
 2334  *  initial state of the membership.
 2335  */
 2336 static int
 2337 igmp_initial_join(struct in_multi *inm, struct igmp_ifsoftc *igi)
 2338 {
 2339         struct ifnet            *ifp;
 2340         struct mbufq            *mq;
 2341         int                      error, retval, syncstates;
 2342  
 2343         CTR4(KTR_IGMPV3, "%s: initial join 0x%08x on ifp %p(%s)", __func__,
 2344             ntohl(inm->inm_addr.s_addr), inm->inm_ifp, 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                         mq = &inm->inm_scq;
 2414                         mbufq_drain(mq);
 2415                         retval = igmp_v3_enqueue_group_record(mq, 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 0x%08x/%s", __func__,
 2454                     ntohl(inm->inm_addr.s_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_ifsoftc *igi)
 2465 {
 2466         struct ifnet            *ifp;
 2467         int                      retval;
 2468 
 2469         CTR4(KTR_IGMPV3, "%s: state change for 0x%08x on ifp %p(%s)", __func__,
 2470             ntohl(inm->inm_addr.s_addr), inm->inm_ifp, inm->inm_ifp->if_xname);
 2471 
 2472         ifp = inm->inm_ifp;
 2473 
 2474         IN_MULTI_LOCK_ASSERT();
 2475         IGMP_LOCK_ASSERT();
 2476 
 2477         KASSERT(igi && igi->igi_ifp == ifp, ("%s: inconsistent ifp", __func__));
 2478 
 2479         if ((ifp->if_flags & IFF_LOOPBACK) ||
 2480             (igi->igi_flags & IGIF_SILENT) ||
 2481             !igmp_isgroupreported(inm->inm_addr) ||
 2482             (igi->igi_version != IGMP_VERSION_3)) {
 2483                 if (!igmp_isgroupreported(inm->inm_addr)) {
 2484                         CTR1(KTR_IGMPV3,
 2485 "%s: not kicking state machine for silent group", __func__);
 2486                 }
 2487                 CTR1(KTR_IGMPV3, "%s: nothing to do", __func__);
 2488                 inm_commit(inm);
 2489                 CTR3(KTR_IGMPV3, "%s: T1 -> T0 for 0x%08x/%s", __func__,
 2490                     ntohl(inm->inm_addr.s_addr), inm->inm_ifp->if_xname);
 2491                 return (0);
 2492         }
 2493 
 2494         mbufq_drain(&inm->inm_scq);
 2495 
 2496         retval = igmp_v3_enqueue_group_record(&inm->inm_scq, inm, 1, 0, 0);
 2497         CTR2(KTR_IGMPV3, "%s: enqueue record = %d", __func__, retval);
 2498         if (retval <= 0)
 2499                 return (-retval);
 2500 
 2501         /*
 2502          * If record(s) were enqueued, start the state-change
 2503          * report timer for this group.
 2504          */
 2505         inm->inm_scrv = ((igi->igi_flags & IGIF_LOOPBACK) ? 1 : igi->igi_rv);
 2506         inm->inm_sctimer = 1;
 2507         V_state_change_timers_running = 1;
 2508 
 2509         return (0);
 2510 }
 2511 
 2512 /*
 2513  * Perform the final leave for an IGMP group.
 2514  *
 2515  * When leaving a group:
 2516  *  IGMPv1 does nothing.
 2517  *  IGMPv2 sends a host leave message, if and only if we are the reporter.
 2518  *  IGMPv3 enqueues a state-change report containing a transition
 2519  *  to INCLUDE {} for immediate transmission.
 2520  */
 2521 static void
 2522 igmp_final_leave(struct in_multi *inm, struct igmp_ifsoftc *igi)
 2523 {
 2524         int syncstates;
 2525 
 2526         syncstates = 1;
 2527 
 2528         CTR4(KTR_IGMPV3, "%s: final leave 0x%08x on ifp %p(%s)",
 2529             __func__, ntohl(inm->inm_addr.s_addr), inm->inm_ifp,
 2530             inm->inm_ifp->if_xname);
 2531 
 2532         IN_MULTI_LOCK_ASSERT();
 2533         IGMP_LOCK_ASSERT();
 2534 
 2535         switch (inm->inm_state) {
 2536         case IGMP_NOT_MEMBER:
 2537         case IGMP_SILENT_MEMBER:
 2538         case IGMP_LEAVING_MEMBER:
 2539                 /* Already leaving or left; do nothing. */
 2540                 CTR1(KTR_IGMPV3,
 2541 "%s: not kicking state machine for silent group", __func__);
 2542                 break;
 2543         case IGMP_REPORTING_MEMBER:
 2544         case IGMP_IDLE_MEMBER:
 2545         case IGMP_G_QUERY_PENDING_MEMBER:
 2546         case IGMP_SG_QUERY_PENDING_MEMBER:
 2547                 if (igi->igi_version == IGMP_VERSION_2) {
 2548 #ifdef INVARIANTS
 2549                         if (inm->inm_state == IGMP_G_QUERY_PENDING_MEMBER ||
 2550                             inm->inm_state == IGMP_SG_QUERY_PENDING_MEMBER)
 2551                         panic("%s: IGMPv3 state reached, not IGMPv3 mode",
 2552                              __func__);
 2553 #endif
 2554                         igmp_v1v2_queue_report(inm, IGMP_HOST_LEAVE_MESSAGE);
 2555                         inm->inm_state = IGMP_NOT_MEMBER;
 2556                 } else if (igi->igi_version == IGMP_VERSION_3) {
 2557                         /*
 2558                          * Stop group timer and all pending reports.
 2559                          * Immediately enqueue a state-change report
 2560                          * TO_IN {} to be sent on the next fast timeout,
 2561                          * giving us an opportunity to merge reports.
 2562                          */
 2563                         mbufq_drain(&inm->inm_scq);
 2564                         inm->inm_timer = 0;
 2565                         if (igi->igi_flags & IGIF_LOOPBACK) {
 2566                                 inm->inm_scrv = 1;
 2567                         } else {
 2568                                 inm->inm_scrv = igi->igi_rv;
 2569                         }
 2570                         CTR4(KTR_IGMPV3, "%s: Leaving 0x%08x/%s with %d "
 2571                             "pending retransmissions.", __func__,
 2572                             ntohl(inm->inm_addr.s_addr),
 2573                             inm->inm_ifp->if_xname, inm->inm_scrv);
 2574                         if (inm->inm_scrv == 0) {
 2575                                 inm->inm_state = IGMP_NOT_MEMBER;
 2576                                 inm->inm_sctimer = 0;
 2577                         } else {
 2578                                 int retval;
 2579 
 2580                                 inm_acquire_locked(inm);
 2581 
 2582                                 retval = igmp_v3_enqueue_group_record(
 2583                                     &inm->inm_scq, inm, 1, 0, 0);
 2584                                 KASSERT(retval != 0,
 2585                                     ("%s: enqueue record = %d", __func__,
 2586                                      retval));
 2587 
 2588                                 inm->inm_state = IGMP_LEAVING_MEMBER;
 2589                                 inm->inm_sctimer = 1;
 2590                                 V_state_change_timers_running = 1;
 2591                                 syncstates = 0;
 2592                         }
 2593                         break;
 2594                 }
 2595                 break;
 2596         case IGMP_LAZY_MEMBER:
 2597         case IGMP_SLEEPING_MEMBER:
 2598         case IGMP_AWAKENING_MEMBER:
 2599                 /* Our reports are suppressed; do nothing. */
 2600                 break;
 2601         }
 2602 
 2603         if (syncstates) {
 2604                 inm_commit(inm);
 2605                 CTR3(KTR_IGMPV3, "%s: T1 -> T0 for 0x%08x/%s", __func__,
 2606                     ntohl(inm->inm_addr.s_addr), inm->inm_ifp->if_xname);
 2607                 inm->inm_st[1].iss_fmode = MCAST_UNDEFINED;
 2608                 CTR3(KTR_IGMPV3, "%s: T1 now MCAST_UNDEFINED for 0x%08x/%s",
 2609                     __func__, ntohl(inm->inm_addr.s_addr),
 2610                     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 mbufq *mq, 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(mq, inm));
 2733 
 2734         if (type == IGMP_DO_NOTHING) {
 2735                 CTR3(KTR_IGMPV3, "%s: nothing to do for 0x%08x/%s", __func__,
 2736                     ntohl(inm->inm_addr.s_addr), inm->inm_ifp->if_xname);
 2737                 return (0);
 2738         }
 2739 
 2740         /*
 2741          * If any sources are present, we must be able to fit at least
 2742          * one in the trailing space of the tail packet's mbuf,
 2743          * ideally more.
 2744          */
 2745         minrec0len = sizeof(struct igmp_grouprec);
 2746         if (record_has_sources)
 2747                 minrec0len += sizeof(in_addr_t);
 2748 
 2749         CTR4(KTR_IGMPV3, "%s: queueing %s for 0x%08x/%s", __func__,
 2750             igmp_rec_type_to_str(type), ntohl(inm->inm_addr.s_addr),
 2751             inm->inm_ifp->if_xname);
 2752 
 2753         /*
 2754          * Check if we have a packet in the tail of the queue for this
 2755          * group into which the first group record for this group will fit.
 2756          * Otherwise allocate a new packet.
 2757          * Always allocate leading space for IP+RA_OPT+IGMP+REPORT.
 2758          * Note: Group records for G/GSR query responses MUST be sent
 2759          * in their own packet.
 2760          */
 2761         m0 = mbufq_last(mq);
 2762         if (!is_group_query &&
 2763             m0 != NULL &&
 2764             (m0->m_pkthdr.PH_vt.vt_nrecs + 1 <= IGMP_V3_REPORT_MAXRECS) &&
 2765             (m0->m_pkthdr.len + minrec0len) <
 2766              (ifp->if_mtu - IGMP_LEADINGSPACE)) {
 2767                 m0srcs = (ifp->if_mtu - m0->m_pkthdr.len -
 2768                             sizeof(struct igmp_grouprec)) / sizeof(in_addr_t);
 2769                 m = m0;
 2770                 CTR1(KTR_IGMPV3, "%s: use existing packet", __func__);
 2771         } else {
 2772                 if (mbufq_full(mq)) {
 2773                         CTR1(KTR_IGMPV3, "%s: outbound queue full", __func__);
 2774                         return (-ENOMEM);
 2775                 }
 2776                 m = NULL;
 2777                 m0srcs = (ifp->if_mtu - IGMP_LEADINGSPACE -
 2778                     sizeof(struct igmp_grouprec)) / sizeof(in_addr_t);
 2779                 if (!is_state_change && !is_group_query) {
 2780                         m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
 2781                         if (m)
 2782                                 m->m_data += IGMP_LEADINGSPACE;
 2783                 }
 2784                 if (m == NULL) {
 2785                         m = m_gethdr(M_NOWAIT, MT_DATA);
 2786                         if (m)
 2787                                 M_ALIGN(m, IGMP_LEADINGSPACE);
 2788                 }
 2789                 if (m == NULL)
 2790                         return (-ENOMEM);
 2791 
 2792                 igmp_save_context(m, ifp);
 2793 
 2794                 CTR1(KTR_IGMPV3, "%s: allocated first packet", __func__);
 2795         }
 2796 
 2797         /*
 2798          * Append group record.
 2799          * If we have sources, we don't know how many yet.
 2800          */
 2801         ig.ig_type = type;
 2802         ig.ig_datalen = 0;
 2803         ig.ig_numsrc = 0;
 2804         ig.ig_group = inm->inm_addr;
 2805         if (!m_append(m, sizeof(struct igmp_grouprec), (void *)&ig)) {
 2806                 if (m != m0)
 2807                         m_freem(m);
 2808                 CTR1(KTR_IGMPV3, "%s: m_append() failed.", __func__);
 2809                 return (-ENOMEM);
 2810         }
 2811         nbytes += sizeof(struct igmp_grouprec);
 2812 
 2813         /*
 2814          * Append as many sources as will fit in the first packet.
 2815          * If we are appending to a new packet, the chain allocation
 2816          * may potentially use clusters; use m_getptr() in this case.
 2817          * If we are appending to an existing packet, we need to obtain
 2818          * a pointer to the group record after m_append(), in case a new
 2819          * mbuf was allocated.
 2820          * Only append sources which are in-mode at t1. If we are
 2821          * transitioning to MCAST_UNDEFINED state on the group, do not
 2822          * include source entries.
 2823          * Only report recorded sources in our filter set when responding
 2824          * to a group-source query.
 2825          */
 2826         if (record_has_sources) {
 2827                 if (m == m0) {
 2828                         md = m_last(m);
 2829                         pig = (struct igmp_grouprec *)(mtod(md, uint8_t *) +
 2830                             md->m_len - nbytes);
 2831                 } else {
 2832                         md = m_getptr(m, 0, &off);
 2833                         pig = (struct igmp_grouprec *)(mtod(md, uint8_t *) +
 2834                             off);
 2835                 }
 2836                 msrcs = 0;
 2837                 RB_FOREACH_SAFE(ims, ip_msource_tree, &inm->inm_srcs, nims) {
 2838                         CTR2(KTR_IGMPV3, "%s: visit node 0x%08x", __func__,
 2839                             ims->ims_haddr);
 2840                         now = ims_get_mode(inm, ims, 1);
 2841                         CTR2(KTR_IGMPV3, "%s: node is %d", __func__, now);
 2842                         if ((now != mode) ||
 2843                             (now == mode && mode == MCAST_UNDEFINED)) {
 2844                                 CTR1(KTR_IGMPV3, "%s: skip node", __func__);
 2845                                 continue;
 2846                         }
 2847                         if (is_source_query && ims->ims_stp == 0) {
 2848                                 CTR1(KTR_IGMPV3, "%s: skip unrecorded node",
 2849                                     __func__);
 2850                                 continue;
 2851                         }
 2852                         CTR1(KTR_IGMPV3, "%s: append node", __func__);
 2853                         naddr = htonl(ims->ims_haddr);
 2854                         if (!m_append(m, sizeof(in_addr_t), (void *)&naddr)) {
 2855                                 if (m != m0)
 2856                                         m_freem(m);
 2857                                 CTR1(KTR_IGMPV3, "%s: m_append() failed.",
 2858                                     __func__);
 2859                                 return (-ENOMEM);
 2860                         }
 2861                         nbytes += sizeof(in_addr_t);
 2862                         ++msrcs;
 2863                         if (msrcs == m0srcs)
 2864                                 break;
 2865                 }
 2866                 CTR2(KTR_IGMPV3, "%s: msrcs is %d this packet", __func__,
 2867                     msrcs);
 2868                 pig->ig_numsrc = htons(msrcs);
 2869                 nbytes += (msrcs * sizeof(in_addr_t));
 2870         }
 2871 
 2872         if (is_source_query && msrcs == 0) {
 2873                 CTR1(KTR_IGMPV3, "%s: no recorded sources to report", __func__);
 2874                 if (m != m0)
 2875                         m_freem(m);
 2876                 return (0);
 2877         }
 2878 
 2879         /*
 2880          * We are good to go with first packet.
 2881          */
 2882         if (m != m0) {
 2883                 CTR1(KTR_IGMPV3, "%s: enqueueing first packet", __func__);
 2884                 m->m_pkthdr.PH_vt.vt_nrecs = 1;
 2885                 mbufq_enqueue(mq, m);
 2886         } else
 2887                 m->m_pkthdr.PH_vt.vt_nrecs++;
 2888 
 2889         /*
 2890          * No further work needed if no source list in packet(s).
 2891          */
 2892         if (!record_has_sources)
 2893                 return (nbytes);
 2894 
 2895         /*
 2896          * Whilst sources remain to be announced, we need to allocate
 2897          * a new packet and fill out as many sources as will fit.
 2898          * Always try for a cluster first.
 2899          */
 2900         while (nims != NULL) {
 2901                 if (mbufq_full(mq)) {
 2902                         CTR1(KTR_IGMPV3, "%s: outbound queue full", __func__);
 2903                         return (-ENOMEM);
 2904                 }
 2905                 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
 2906                 if (m)
 2907                         m->m_data += IGMP_LEADINGSPACE;
 2908                 if (m == NULL) {
 2909                         m = m_gethdr(M_NOWAIT, MT_DATA);
 2910                         if (m)
 2911                                 M_ALIGN(m, IGMP_LEADINGSPACE);
 2912                 }
 2913                 if (m == NULL)
 2914                         return (-ENOMEM);
 2915                 igmp_save_context(m, ifp);
 2916                 md = m_getptr(m, 0, &off);
 2917                 pig = (struct igmp_grouprec *)(mtod(md, uint8_t *) + off);
 2918                 CTR1(KTR_IGMPV3, "%s: allocated next packet", __func__);
 2919 
 2920                 if (!m_append(m, sizeof(struct igmp_grouprec), (void *)&ig)) {
 2921                         if (m != m0)
 2922                                 m_freem(m);
 2923                         CTR1(KTR_IGMPV3, "%s: m_append() failed.", __func__);
 2924                         return (-ENOMEM);
 2925                 }
 2926                 m->m_pkthdr.PH_vt.vt_nrecs = 1;
 2927                 nbytes += sizeof(struct igmp_grouprec);
 2928 
 2929                 m0srcs = (ifp->if_mtu - IGMP_LEADINGSPACE -
 2930                     sizeof(struct igmp_grouprec)) / sizeof(in_addr_t);
 2931 
 2932                 msrcs = 0;
 2933                 RB_FOREACH_FROM(ims, ip_msource_tree, nims) {
 2934                         CTR2(KTR_IGMPV3, "%s: visit node 0x%08x", __func__,
 2935                             ims->ims_haddr);
 2936                         now = ims_get_mode(inm, ims, 1);
 2937                         if ((now != mode) ||
 2938                             (now == mode && mode == MCAST_UNDEFINED)) {
 2939                                 CTR1(KTR_IGMPV3, "%s: skip node", __func__);
 2940                                 continue;
 2941                         }
 2942                         if (is_source_query && ims->ims_stp == 0) {
 2943                                 CTR1(KTR_IGMPV3, "%s: skip unrecorded node",
 2944                                     __func__);
 2945                                 continue;
 2946                         }
 2947                         CTR1(KTR_IGMPV3, "%s: append node", __func__);
 2948                         naddr = htonl(ims->ims_haddr);
 2949                         if (!m_append(m, sizeof(in_addr_t), (void *)&naddr)) {
 2950                                 if (m != m0)
 2951                                         m_freem(m);
 2952                                 CTR1(KTR_IGMPV3, "%s: m_append() failed.",
 2953                                     __func__);
 2954                                 return (-ENOMEM);
 2955                         }
 2956                         ++msrcs;
 2957                         if (msrcs == m0srcs)
 2958                                 break;
 2959                 }
 2960                 pig->ig_numsrc = htons(msrcs);
 2961                 nbytes += (msrcs * sizeof(in_addr_t));
 2962 
 2963                 CTR1(KTR_IGMPV3, "%s: enqueueing next packet", __func__);
 2964                 mbufq_enqueue(mq, m);
 2965         }
 2966 
 2967         return (nbytes);
 2968 }
 2969 
 2970 /*
 2971  * Type used to mark record pass completion.
 2972  * We exploit the fact we can cast to this easily from the
 2973  * current filter modes on each ip_msource node.
 2974  */
 2975 typedef enum {
 2976         REC_NONE = 0x00,        /* MCAST_UNDEFINED */
 2977         REC_ALLOW = 0x01,       /* MCAST_INCLUDE */
 2978         REC_BLOCK = 0x02,       /* MCAST_EXCLUDE */
 2979         REC_FULL = REC_ALLOW | REC_BLOCK
 2980 } rectype_t;
 2981 
 2982 /*
 2983  * Enqueue an IGMPv3 filter list change to the given output queue.
 2984  *
 2985  * Source list filter state is held in an RB-tree. When the filter list
 2986  * for a group is changed without changing its mode, we need to compute
 2987  * the deltas between T0 and T1 for each source in the filter set,
 2988  * and enqueue the appropriate ALLOW_NEW/BLOCK_OLD records.
 2989  *
 2990  * As we may potentially queue two record types, and the entire R-B tree
 2991  * needs to be walked at once, we break this out into its own function
 2992  * so we can generate a tightly packed queue of packets.
 2993  *
 2994  * XXX This could be written to only use one tree walk, although that makes
 2995  * serializing into the mbuf chains a bit harder. For now we do two walks
 2996  * which makes things easier on us, and it may or may not be harder on
 2997  * the L2 cache.
 2998  *
 2999  * If successful the size of all data appended to the queue is returned,
 3000  * otherwise an error code less than zero is returned, or zero if
 3001  * no record(s) were appended.
 3002  */
 3003 static int
 3004 igmp_v3_enqueue_filter_change(struct mbufq *mq, struct in_multi *inm)
 3005 {
 3006         static const int MINRECLEN =
 3007             sizeof(struct igmp_grouprec) + sizeof(in_addr_t);
 3008         struct ifnet            *ifp;
 3009         struct igmp_grouprec     ig;
 3010         struct igmp_grouprec    *pig;
 3011         struct ip_msource       *ims, *nims;
 3012         struct mbuf             *m, *m0, *md;
 3013         in_addr_t                naddr;
 3014         int                      m0srcs, nbytes, npbytes, off, rsrcs, schanged;
 3015         int                      nallow, nblock;
 3016         uint8_t                  mode, now, then;
 3017         rectype_t                crt, drt, nrt;
 3018 
 3019         IN_MULTI_LOCK_ASSERT();
 3020 
 3021         if (inm->inm_nsrc == 0 ||
 3022             (inm->inm_st[0].iss_asm > 0 && inm->inm_st[1].iss_asm > 0))
 3023                 return (0);
 3024 
 3025         ifp = inm->inm_ifp;                     /* interface */
 3026         mode = inm->inm_st[1].iss_fmode;        /* filter mode at t1 */
 3027         crt = REC_NONE; /* current group record type */
 3028         drt = REC_NONE; /* mask of completed group record types */
 3029         nrt = REC_NONE; /* record type for current node */
 3030         m0srcs = 0;     /* # source which will fit in current mbuf chain */
 3031         nbytes = 0;     /* # of bytes appended to group's state-change queue */
 3032         npbytes = 0;    /* # of bytes appended this packet */
 3033         rsrcs = 0;      /* # sources encoded in current record */
 3034         schanged = 0;   /* # nodes encoded in overall filter change */
 3035         nallow = 0;     /* # of source entries in ALLOW_NEW */
 3036         nblock = 0;     /* # of source entries in BLOCK_OLD */
 3037         nims = NULL;    /* next tree node pointer */
 3038 
 3039         /*
 3040          * For each possible filter record mode.
 3041          * The first kind of source we encounter tells us which
 3042          * is the first kind of record we start appending.
 3043          * If a node transitioned to UNDEFINED at t1, its mode is treated
 3044          * as the inverse of the group's filter mode.
 3045          */
 3046         while (drt != REC_FULL) {
 3047                 do {
 3048                         m0 = mbufq_last(mq);
 3049                         if (m0 != NULL &&
 3050                             (m0->m_pkthdr.PH_vt.vt_nrecs + 1 <=
 3051                              IGMP_V3_REPORT_MAXRECS) &&
 3052                             (m0->m_pkthdr.len + MINRECLEN) <
 3053                              (ifp->if_mtu - IGMP_LEADINGSPACE)) {
 3054                                 m = m0;
 3055                                 m0srcs = (ifp->if_mtu - m0->m_pkthdr.len -
 3056                                             sizeof(struct igmp_grouprec)) /
 3057                                     sizeof(in_addr_t);
 3058                                 CTR1(KTR_IGMPV3,
 3059                                     "%s: use previous packet", __func__);
 3060                         } else {
 3061                                 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
 3062                                 if (m)
 3063                                         m->m_data += IGMP_LEADINGSPACE;
 3064                                 if (m == NULL) {
 3065                                         m = m_gethdr(M_NOWAIT, MT_DATA);
 3066                                         if (m)
 3067                                                 M_ALIGN(m, IGMP_LEADINGSPACE);
 3068                                 }
 3069                                 if (m == NULL) {
 3070                                         CTR1(KTR_IGMPV3,
 3071                                             "%s: m_get*() failed", __func__);
 3072                                         return (-ENOMEM);
 3073                                 }
 3074                                 m->m_pkthdr.PH_vt.vt_nrecs = 0;
 3075                                 igmp_save_context(m, ifp);
 3076                                 m0srcs = (ifp->if_mtu - IGMP_LEADINGSPACE -
 3077                                     sizeof(struct igmp_grouprec)) /
 3078                                     sizeof(in_addr_t);
 3079                                 npbytes = 0;
 3080                                 CTR1(KTR_IGMPV3,
 3081                                     "%s: allocated new packet", __func__);
 3082                         }
 3083                         /*
 3084                          * Append the IGMP group record header to the
 3085                          * current packet's data area.
 3086                          * Recalculate pointer to free space for next
 3087                          * group record, in case m_append() allocated
 3088                          * a new mbuf or cluster.
 3089                          */
 3090                         memset(&ig, 0, sizeof(ig));
 3091                         ig.ig_group = inm->inm_addr;
 3092                         if (!m_append(m, sizeof(ig), (void *)&ig)) {
 3093                                 if (m != m0)
 3094                                         m_freem(m);
 3095                                 CTR1(KTR_IGMPV3,
 3096                                     "%s: m_append() failed", __func__);
 3097                                 return (-ENOMEM);
 3098                         }
 3099                         npbytes += sizeof(struct igmp_grouprec);
 3100                         if (m != m0) {
 3101                                 /* new packet; offset in c hain */
 3102                                 md = m_getptr(m, npbytes -
 3103                                     sizeof(struct igmp_grouprec), &off);
 3104                                 pig = (struct igmp_grouprec *)(mtod(md,
 3105                                     uint8_t *) + off);
 3106                         } else {
 3107                                 /* current packet; offset from last append */
 3108                                 md = m_last(m);
 3109                                 pig = (struct igmp_grouprec *)(mtod(md,
 3110                                     uint8_t *) + md->m_len -
 3111                                     sizeof(struct igmp_grouprec));
 3112                         }
 3113                         /*
 3114                          * Begin walking the tree for this record type
 3115                          * pass, or continue from where we left off
 3116                          * previously if we had to allocate a new packet.
 3117                          * Only report deltas in-mode at t1.
 3118                          * We need not report included sources as allowed
 3119                          * if we are in inclusive mode on the group,
 3120                          * however the converse is not true.
 3121                          */
 3122                         rsrcs = 0;
 3123                         if (nims == NULL)
 3124                                 nims = RB_MIN(ip_msource_tree, &inm->inm_srcs);
 3125                         RB_FOREACH_FROM(ims, ip_msource_tree, nims) {
 3126                                 CTR2(KTR_IGMPV3, "%s: visit node 0x%08x",
 3127                                     __func__, ims->ims_haddr);
 3128                                 now = ims_get_mode(inm, ims, 1);
 3129                                 then = ims_get_mode(inm, ims, 0);
 3130                                 CTR3(KTR_IGMPV3, "%s: mode: t0 %d, t1 %d",
 3131                                     __func__, then, now);
 3132                                 if (now == then) {
 3133                                         CTR1(KTR_IGMPV3,
 3134                                             "%s: skip unchanged", __func__);
 3135                                         continue;
 3136                                 }
 3137                                 if (mode == MCAST_EXCLUDE &&
 3138                                     now == MCAST_INCLUDE) {
 3139                                         CTR1(KTR_IGMPV3,
 3140                                             "%s: skip IN src on EX group",
 3141                                             __func__);
 3142                                         continue;
 3143                                 }
 3144                                 nrt = (rectype_t)now;
 3145                                 if (nrt == REC_NONE)
 3146                                         nrt = (rectype_t)(~mode & REC_FULL);
 3147                                 if (schanged++ == 0) {
 3148                                         crt = nrt;
 3149                                 } else if (crt != nrt)
 3150                                         continue;
 3151                                 naddr = htonl(ims->ims_haddr);
 3152                                 if (!m_append(m, sizeof(in_addr_t),
 3153                                     (void *)&naddr)) {
 3154                                         if (m != m0)
 3155                                                 m_freem(m);
 3156                                         CTR1(KTR_IGMPV3,
 3157                                             "%s: m_append() failed", __func__);
 3158                                         return (-ENOMEM);
 3159                                 }
 3160                                 nallow += !!(crt == REC_ALLOW);
 3161                                 nblock += !!(crt == REC_BLOCK);
 3162                                 if (++rsrcs == m0srcs)
 3163                                         break;
 3164                         }
 3165                         /*
 3166                          * If we did not append any tree nodes on this
 3167                          * pass, back out of allocations.
 3168                          */
 3169                         if (rsrcs == 0) {
 3170                                 npbytes -= sizeof(struct igmp_grouprec);
 3171                                 if (m != m0) {
 3172                                         CTR1(KTR_IGMPV3,
 3173                                             "%s: m_free(m)", __func__);
 3174                                         m_freem(m);
 3175                                 } else {
 3176                                         CTR1(KTR_IGMPV3,
 3177                                             "%s: m_adj(m, -ig)", __func__);
 3178                                         m_adj(m, -((int)sizeof(
 3179                                             struct igmp_grouprec)));
 3180                                 }
 3181                                 continue;
 3182                         }
 3183                         npbytes += (rsrcs * sizeof(in_addr_t));
 3184                         if (crt == REC_ALLOW)
 3185                                 pig->ig_type = IGMP_ALLOW_NEW_SOURCES;
 3186                         else if (crt == REC_BLOCK)
 3187                                 pig->ig_type = IGMP_BLOCK_OLD_SOURCES;
 3188                         pig->ig_numsrc = htons(rsrcs);
 3189                         /*
 3190                          * Count the new group record, and enqueue this
 3191                          * packet if it wasn't already queued.
 3192                          */
 3193                         m->m_pkthdr.PH_vt.vt_nrecs++;
 3194                         if (m != m0)
 3195                                 mbufq_enqueue(mq, m);
 3196                         nbytes += npbytes;
 3197                 } while (nims != NULL);
 3198                 drt |= crt;
 3199                 crt = (~crt & REC_FULL);
 3200         }
 3201 
 3202         CTR3(KTR_IGMPV3, "%s: queued %d ALLOW_NEW, %d BLOCK_OLD", __func__,
 3203             nallow, nblock);
 3204 
 3205         return (nbytes);
 3206 }
 3207 
 3208 static int
 3209 igmp_v3_merge_state_changes(struct in_multi *inm, struct mbufq *scq)
 3210 {
 3211         struct mbufq    *gq;
 3212         struct mbuf     *m;             /* pending state-change */
 3213         struct mbuf     *m0;            /* copy of pending state-change */
 3214         struct mbuf     *mt;            /* last state-change in packet */
 3215         int              docopy, domerge;
 3216         u_int            recslen;
 3217 
 3218         docopy = 0;
 3219         domerge = 0;
 3220         recslen = 0;
 3221 
 3222         IN_MULTI_LOCK_ASSERT();
 3223         IGMP_LOCK_ASSERT();
 3224 
 3225         /*
 3226          * If there are further pending retransmissions, make a writable
 3227          * copy of each queued state-change message before merging.
 3228          */
 3229         if (inm->inm_scrv > 0)
 3230                 docopy = 1;
 3231 
 3232         gq = &inm->inm_scq;
 3233 #ifdef KTR
 3234         if (mbufq_first(gq) == NULL) {
 3235                 CTR2(KTR_IGMPV3, "%s: WARNING: queue for inm %p is empty",
 3236                     __func__, inm);
 3237         }
 3238 #endif
 3239 
 3240         m = mbufq_first(gq);
 3241         while (m != NULL) {
 3242                 /*
 3243                  * Only merge the report into the current packet if
 3244                  * there is sufficient space to do so; an IGMPv3 report
 3245                  * packet may only contain 65,535 group records.
 3246                  * Always use a simple mbuf chain concatentation to do this,
 3247                  * as large state changes for single groups may have
 3248                  * allocated clusters.
 3249                  */
 3250                 domerge = 0;
 3251                 mt = mbufq_last(scq);
 3252                 if (mt != NULL) {
 3253                         recslen = m_length(m, NULL);
 3254 
 3255                         if ((mt->m_pkthdr.PH_vt.vt_nrecs +
 3256                             m->m_pkthdr.PH_vt.vt_nrecs <=
 3257                             IGMP_V3_REPORT_MAXRECS) &&
 3258                             (mt->m_pkthdr.len + recslen <=
 3259                             (inm->inm_ifp->if_mtu - IGMP_LEADINGSPACE)))
 3260                                 domerge = 1;
 3261                 }
 3262 
 3263                 if (!domerge && mbufq_full(gq)) {
 3264                         CTR2(KTR_IGMPV3,
 3265                             "%s: outbound queue full, skipping whole packet %p",
 3266                             __func__, m);
 3267                         mt = m->m_nextpkt;
 3268                         if (!docopy)
 3269                                 m_freem(m);
 3270                         m = mt;
 3271                         continue;
 3272                 }
 3273 
 3274                 if (!docopy) {
 3275                         CTR2(KTR_IGMPV3, "%s: dequeueing %p", __func__, m);
 3276                         m0 = mbufq_dequeue(gq);
 3277                         m = m0->m_nextpkt;
 3278                 } else {
 3279                         CTR2(KTR_IGMPV3, "%s: copying %p", __func__, m);
 3280                         m0 = m_dup(m, M_NOWAIT);
 3281                         if (m0 == NULL)
 3282                                 return (ENOMEM);
 3283                         m0->m_nextpkt = NULL;
 3284                         m = m->m_nextpkt;
 3285                 }
 3286 
 3287                 if (!domerge) {
 3288                         CTR3(KTR_IGMPV3, "%s: queueing %p to scq %p)",
 3289                             __func__, m0, scq);
 3290                         mbufq_enqueue(scq, m0);
 3291                 } else {
 3292                         struct mbuf *mtl;       /* last mbuf of packet mt */
 3293 
 3294                         CTR3(KTR_IGMPV3, "%s: merging %p with scq tail %p)",
 3295                             __func__, m0, mt);
 3296 
 3297                         mtl = m_last(mt);
 3298                         m0->m_flags &= ~M_PKTHDR;
 3299                         mt->m_pkthdr.len += recslen;
 3300                         mt->m_pkthdr.PH_vt.vt_nrecs +=
 3301                             m0->m_pkthdr.PH_vt.vt_nrecs;
 3302 
 3303                         mtl->m_next = m0;
 3304                 }
 3305         }
 3306 
 3307         return (0);
 3308 }
 3309 
 3310 /*
 3311  * Respond to a pending IGMPv3 General Query.
 3312  */
 3313 static void
 3314 igmp_v3_dispatch_general_query(struct igmp_ifsoftc *igi)
 3315 {
 3316         struct ifmultiaddr      *ifma;
 3317         struct ifnet            *ifp;
 3318         struct in_multi         *inm;
 3319         int                      retval, loop;
 3320 
 3321         IN_MULTI_LOCK_ASSERT();
 3322         IGMP_LOCK_ASSERT();
 3323 
 3324         KASSERT(igi->igi_version == IGMP_VERSION_3,
 3325             ("%s: called when version %d", __func__, igi->igi_version));
 3326 
 3327         /*
 3328          * Check that there are some packets queued. If so, send them first.
 3329          * For large number of groups the reply to general query can take
 3330          * many packets, we should finish sending them before starting of
 3331          * queuing the new reply.
 3332          */
 3333         if (mbufq_len(&igi->igi_gq) != 0)
 3334                 goto send;
 3335 
 3336         ifp = igi->igi_ifp;
 3337 
 3338         IF_ADDR_RLOCK(ifp);
 3339         TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
 3340                 if (ifma->ifma_addr->sa_family != AF_INET ||
 3341                     ifma->ifma_protospec == NULL)
 3342                         continue;
 3343 
 3344                 inm = (struct in_multi *)ifma->ifma_protospec;
 3345                 KASSERT(ifp == inm->inm_ifp,
 3346                     ("%s: inconsistent ifp", __func__));
 3347 
 3348                 switch (inm->inm_state) {
 3349                 case IGMP_NOT_MEMBER:
 3350                 case IGMP_SILENT_MEMBER:
 3351                         break;
 3352                 case IGMP_REPORTING_MEMBER:
 3353                 case IGMP_IDLE_MEMBER:
 3354                 case IGMP_LAZY_MEMBER:
 3355                 case IGMP_SLEEPING_MEMBER:
 3356                 case IGMP_AWAKENING_MEMBER:
 3357                         inm->inm_state = IGMP_REPORTING_MEMBER;
 3358                         retval = igmp_v3_enqueue_group_record(&igi->igi_gq,
 3359                             inm, 0, 0, 0);
 3360                         CTR2(KTR_IGMPV3, "%s: enqueue record = %d",
 3361                             __func__, retval);
 3362                         break;
 3363                 case IGMP_G_QUERY_PENDING_MEMBER:
 3364                 case IGMP_SG_QUERY_PENDING_MEMBER:
 3365                 case IGMP_LEAVING_MEMBER:
 3366                         break;
 3367                 }
 3368         }
 3369         IF_ADDR_RUNLOCK(ifp);
 3370 
 3371 send:
 3372         loop = (igi->igi_flags & IGIF_LOOPBACK) ? 1 : 0;
 3373         igmp_dispatch_queue(&igi->igi_gq, IGMP_MAX_RESPONSE_BURST, loop);
 3374 
 3375         /*
 3376          * Slew transmission of bursts over 500ms intervals.
 3377          */
 3378         if (mbufq_first(&igi->igi_gq) != NULL) {
 3379                 igi->igi_v3_timer = 1 + IGMP_RANDOM_DELAY(
 3380                     IGMP_RESPONSE_BURST_INTERVAL);
 3381                 V_interface_timers_running = 1;
 3382         }
 3383 }
 3384 
 3385 /*
 3386  * Transmit the next pending IGMP message in the output queue.
 3387  *
 3388  * We get called from netisr_processqueue(). A mutex private to igmpoq
 3389  * will be acquired and released around this routine.
 3390  *
 3391  * VIMAGE: Needs to store/restore vnet pointer on a per-mbuf-chain basis.
 3392  * MRT: Nothing needs to be done, as IGMP traffic is always local to
 3393  * a link and uses a link-scope multicast address.
 3394  */
 3395 static void
 3396 igmp_intr(struct mbuf *m)
 3397 {
 3398         struct ip_moptions       imo;
 3399         struct ifnet            *ifp;
 3400         struct mbuf             *ipopts, *m0;
 3401         int                      error;
 3402         uint32_t                 ifindex;
 3403 
 3404         CTR2(KTR_IGMPV3, "%s: transmit %p", __func__, m);
 3405 
 3406         /*
 3407          * Set VNET image pointer from enqueued mbuf chain
 3408          * before doing anything else. Whilst we use interface
 3409          * indexes to guard against interface detach, they are
 3410          * unique to each VIMAGE and must be retrieved.
 3411          */
 3412         CURVNET_SET((struct vnet *)(m->m_pkthdr.PH_loc.ptr));
 3413         ifindex = igmp_restore_context(m);
 3414 
 3415         /*
 3416          * Check if the ifnet still exists. This limits the scope of
 3417          * any race in the absence of a global ifp lock for low cost
 3418          * (an array lookup).
 3419          */
 3420         ifp = ifnet_byindex(ifindex);
 3421         if (ifp == NULL) {
 3422                 CTR3(KTR_IGMPV3, "%s: dropped %p as ifindex %u went away.",
 3423                     __func__, m, ifindex);
 3424                 m_freem(m);
 3425                 IPSTAT_INC(ips_noroute);
 3426                 goto out;
 3427         }
 3428 
 3429         ipopts = V_igmp_sendra ? m_raopt : NULL;
 3430 
 3431         imo.imo_multicast_ttl  = 1;
 3432         imo.imo_multicast_vif  = -1;
 3433         imo.imo_multicast_loop = (V_ip_mrouter != NULL);
 3434 
 3435         /*
 3436          * If the user requested that IGMP traffic be explicitly
 3437          * redirected to the loopback interface (e.g. they are running a
 3438          * MANET interface and the routing protocol needs to see the
 3439          * updates), handle this now.
 3440          */
 3441         if (m->m_flags & M_IGMP_LOOP)
 3442                 imo.imo_multicast_ifp = V_loif;
 3443         else
 3444                 imo.imo_multicast_ifp = ifp;
 3445 
 3446         if (m->m_flags & M_IGMPV2) {
 3447                 m0 = m;
 3448         } else {
 3449                 m0 = igmp_v3_encap_report(ifp, m);
 3450                 if (m0 == NULL) {
 3451                         CTR2(KTR_IGMPV3, "%s: dropped %p", __func__, m);
 3452                         m_freem(m);
 3453                         IPSTAT_INC(ips_odropped);
 3454                         goto out;
 3455                 }
 3456         }
 3457 
 3458         igmp_scrub_context(m0);
 3459         m_clrprotoflags(m);
 3460         m0->m_pkthdr.rcvif = V_loif;
 3461 #ifdef MAC
 3462         mac_netinet_igmp_send(ifp, m0);
 3463 #endif
 3464         error = ip_output(m0, ipopts, NULL, 0, &imo, NULL);
 3465         if (error) {
 3466                 CTR3(KTR_IGMPV3, "%s: ip_output(%p) = %d", __func__, m0, error);
 3467                 goto out;
 3468         }
 3469 
 3470         IGMPSTAT_INC(igps_snd_reports);
 3471 
 3472 out:
 3473         /*
 3474          * We must restore the existing vnet pointer before
 3475          * continuing as we are run from netisr context.
 3476          */
 3477         CURVNET_RESTORE();
 3478 }
 3479 
 3480 /*
 3481  * Encapsulate an IGMPv3 report.
 3482  *
 3483  * The internal mbuf flag M_IGMPV3_HDR is used to indicate that the mbuf
 3484  * chain has already had its IP/IGMPv3 header prepended. In this case
 3485  * the function will not attempt to prepend; the lengths and checksums
 3486  * will however be re-computed.
 3487  *
 3488  * Returns a pointer to the new mbuf chain head, or NULL if the
 3489  * allocation failed.
 3490  */
 3491 static struct mbuf *
 3492 igmp_v3_encap_report(struct ifnet *ifp, struct mbuf *m)
 3493 {
 3494         struct rm_priotracker   in_ifa_tracker;
 3495         struct igmp_report      *igmp;
 3496         struct ip               *ip;
 3497         int                      hdrlen, igmpreclen;
 3498 
 3499         KASSERT((m->m_flags & M_PKTHDR),
 3500             ("%s: mbuf chain %p is !M_PKTHDR", __func__, m));
 3501 
 3502         igmpreclen = m_length(m, NULL);
 3503         hdrlen = sizeof(struct ip) + sizeof(struct igmp_report);
 3504 
 3505         if (m->m_flags & M_IGMPV3_HDR) {
 3506                 igmpreclen -= hdrlen;
 3507         } else {
 3508                 M_PREPEND(m, hdrlen, M_NOWAIT);
 3509                 if (m == NULL)
 3510                         return (NULL);
 3511                 m->m_flags |= M_IGMPV3_HDR;
 3512         }
 3513 
 3514         CTR2(KTR_IGMPV3, "%s: igmpreclen is %d", __func__, igmpreclen);
 3515 
 3516         m->m_data += sizeof(struct ip);
 3517         m->m_len -= sizeof(struct ip);
 3518 
 3519         igmp = mtod(m, struct igmp_report *);
 3520         igmp->ir_type = IGMP_v3_HOST_MEMBERSHIP_REPORT;
 3521         igmp->ir_rsv1 = 0;
 3522         igmp->ir_rsv2 = 0;
 3523         igmp->ir_numgrps = htons(m->m_pkthdr.PH_vt.vt_nrecs);
 3524         igmp->ir_cksum = 0;
 3525         igmp->ir_cksum = in_cksum(m, sizeof(struct igmp_report) + igmpreclen);
 3526         m->m_pkthdr.PH_vt.vt_nrecs = 0;
 3527 
 3528         m->m_data -= sizeof(struct ip);
 3529         m->m_len += sizeof(struct ip);
 3530 
 3531         ip = mtod(m, struct ip *);
 3532         ip->ip_tos = IPTOS_PREC_INTERNETCONTROL;
 3533         ip->ip_len = htons(hdrlen + igmpreclen);
 3534         ip->ip_off = htons(IP_DF);
 3535         ip->ip_p = IPPROTO_IGMP;
 3536         ip->ip_sum = 0;
 3537 
 3538         ip->ip_src.s_addr = INADDR_ANY;
 3539 
 3540         if (m->m_flags & M_IGMP_LOOP) {
 3541                 struct in_ifaddr *ia;
 3542 
 3543                 IFP_TO_IA(ifp, ia, &in_ifa_tracker);
 3544                 if (ia != NULL) {
 3545                         ip->ip_src = ia->ia_addr.sin_addr;
 3546                         ifa_free(&ia->ia_ifa);
 3547                 }
 3548         }
 3549 
 3550         ip->ip_dst.s_addr = htonl(INADDR_ALLRPTS_GROUP);
 3551 
 3552         return (m);
 3553 }
 3554 
 3555 #ifdef KTR
 3556 static char *
 3557 igmp_rec_type_to_str(const int type)
 3558 {
 3559 
 3560         switch (type) {
 3561                 case IGMP_CHANGE_TO_EXCLUDE_MODE:
 3562                         return "TO_EX";
 3563                         break;
 3564                 case IGMP_CHANGE_TO_INCLUDE_MODE:
 3565                         return "TO_IN";
 3566                         break;
 3567                 case IGMP_MODE_IS_EXCLUDE:
 3568                         return "MODE_EX";
 3569                         break;
 3570                 case IGMP_MODE_IS_INCLUDE:
 3571                         return "MODE_IN";
 3572                         break;
 3573                 case IGMP_ALLOW_NEW_SOURCES:
 3574                         return "ALLOW_NEW";
 3575                         break;
 3576                 case IGMP_BLOCK_OLD_SOURCES:
 3577                         return "BLOCK_OLD";
 3578                         break;
 3579                 default:
 3580                         break;
 3581         }
 3582         return "unknown";
 3583 }
 3584 #endif
 3585 
 3586 #ifdef VIMAGE
 3587 static void
 3588 vnet_igmp_init(const void *unused __unused)
 3589 {
 3590 
 3591         netisr_register_vnet(&igmp_nh);
 3592 }
 3593 VNET_SYSINIT(vnet_igmp_init, SI_SUB_PROTO_MC, SI_ORDER_ANY,
 3594     vnet_igmp_init, NULL);
 3595 
 3596 static void
 3597 vnet_igmp_uninit(const void *unused __unused)
 3598 {
 3599 
 3600         /* This can happen when we shutdown the entire network stack. */
 3601         CTR1(KTR_IGMPV3, "%s: tearing down", __func__);
 3602 
 3603         netisr_unregister_vnet(&igmp_nh);
 3604 }
 3605 VNET_SYSUNINIT(vnet_igmp_uninit, SI_SUB_PROTO_MC, SI_ORDER_ANY,
 3606     vnet_igmp_uninit, NULL);
 3607 #endif
 3608 
 3609 #ifdef DDB
 3610 DB_SHOW_COMMAND(igi_list, db_show_igi_list)
 3611 {
 3612         struct igmp_ifsoftc *igi, *tigi;
 3613         LIST_HEAD(_igi_list, igmp_ifsoftc) *igi_head;
 3614 
 3615         if (!have_addr) {
 3616                 db_printf("usage: show igi_list <addr>\n");
 3617                 return;
 3618         }
 3619         igi_head = (struct _igi_list *)addr;
 3620 
 3621         LIST_FOREACH_SAFE(igi, igi_head, igi_link, tigi) {
 3622                 db_printf("igmp_ifsoftc %p:\n", igi);
 3623                 db_printf("    ifp %p\n", igi->igi_ifp);
 3624                 db_printf("    version %u\n", igi->igi_version);
 3625                 db_printf("    v1_timer %u\n", igi->igi_v1_timer);
 3626                 db_printf("    v2_timer %u\n", igi->igi_v2_timer);
 3627                 db_printf("    v3_timer %u\n", igi->igi_v3_timer);
 3628                 db_printf("    flags %#x\n", igi->igi_flags);
 3629                 db_printf("    rv %u\n", igi->igi_rv);
 3630                 db_printf("    qi %u\n", igi->igi_qi);
 3631                 db_printf("    qri %u\n", igi->igi_qri);
 3632                 db_printf("    uri %u\n", igi->igi_uri);
 3633                 /* SLIST_HEAD(,in_multi)   igi_relinmhead */
 3634                 /* struct mbufq    igi_gq; */
 3635                 db_printf("\n");
 3636         }
 3637 }
 3638 #endif
 3639 
 3640 static int
 3641 igmp_modevent(module_t mod, int type, void *unused __unused)
 3642 {
 3643 
 3644         switch (type) {
 3645         case MOD_LOAD:
 3646                 CTR1(KTR_IGMPV3, "%s: initializing", __func__);
 3647                 IGMP_LOCK_INIT();
 3648                 m_raopt = igmp_ra_alloc();
 3649                 netisr_register(&igmp_nh);
 3650                 break;
 3651         case MOD_UNLOAD:
 3652                 CTR1(KTR_IGMPV3, "%s: tearing down", __func__);
 3653                 netisr_unregister(&igmp_nh);
 3654                 m_free(m_raopt);
 3655                 m_raopt = NULL;
 3656                 IGMP_LOCK_DESTROY();
 3657                 break;
 3658         default:
 3659                 return (EOPNOTSUPP);
 3660         }
 3661         return (0);
 3662 }
 3663 
 3664 static moduledata_t igmp_mod = {
 3665     "igmp",
 3666     igmp_modevent,
 3667     0
 3668 };
 3669 DECLARE_MODULE(igmp, igmp_mod, SI_SUB_PROTO_MC, SI_ORDER_MIDDLE);

Cache object: 68584ffec7774eb0578605ce6e106498


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.