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Implement IGMP v2. Based on the Multicast 3.5 distribution.

This commit is contained in:
mycroft 1995-05-31 06:08:17 +00:00
parent ae4eae4f63
commit f49ddb8b04
5 changed files with 365 additions and 118 deletions
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406
sys/netinet/igmp.c
View File

@ -1,47 +1,15 @@
/* $NetBSD: igmp.c,v 1.9 1995/04/13 06:26:19 cgd Exp $ */
/* $NetBSD: igmp.c,v 1.10 1995/05/31 06:08:17 mycroft Exp $ */
/*
* Copyright (c) 1988 Stephen Deering.
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
* Internet Group Management Protocol (IGMP) routines.
*
* This code is derived from software contributed to Berkeley by
* Stephen Deering of Stanford University.
* Written by Steve Deering, Stanford, May 1988.
* Modified by Rosen Sharma, Stanford, Aug 1994.
* Modified by Bill Fenner, Xerox PARC, Feb 1995.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)igmp.c 8.1 (Berkeley) 7/19/93
* MULTICAST Revision: 1.3
*/
/* Internet Group Management Protocol (IGMP) routines. */
#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
@ -58,18 +26,76 @@
#include <netinet/igmp.h>
#include <netinet/igmp_var.h>
static int igmp_timers_are_running = 0;
static u_int32_t igmp_all_hosts_group;
#define IP_MULTICASTOPTS 0
#define IN_LOCAL_GROUP(addr) \
(((addr) & igmp_local_group_mask) == igmp_local_group)
static void igmp_sendreport __P((struct in_multi *));
int igmp_timers_are_running;
u_int32_t igmp_all_hosts_group;
u_int32_t igmp_local_group;
u_int32_t igmp_local_group_mask;
static struct router_info *rti_head;
void igmp_sendpkt __P((struct in_multi *, int));
void
igmp_init()
{
/*
* To avoid byte-swapping the same value over and over again.
*/
igmp_timers_are_running = 0;
igmp_all_hosts_group = htonl(INADDR_ALLHOSTS_GROUP);
igmp_local_group = htonl(INADDR_UNSPEC_GROUP);
igmp_local_group_mask = htonl(IN_CLASSC_NET);
rti_head = 0;
}
static int
rti_fill(inm)
struct in_multi *inm;
{
register struct router_info *rti;
for (rti = rti_head; rti != 0; rti = rti->rti_next) {
if (rti->rti_ifp == inm->inm_ifp) {
inm->inm_rti = rti;
if (rti->rti_type == IGMP_v1_ROUTER)
return (IGMP_v1_HOST_MEMBERSHIP_REPORT);
else
return (IGMP_v2_HOST_MEMBERSHIP_REPORT);
}
}
rti = (struct router_info *)malloc(sizeof(struct router_info),
M_MRTABLE, M_NOWAIT);
rti->rti_ifp = inm->inm_ifp;
rti->rti_type = IGMP_v2_ROUTER;
rti->rti_next = rti_head;
rti_head = rti;
inm->inm_rti = rti;
return (IGMP_v2_HOST_MEMBERSHIP_REPORT);
}
static struct router_info *
rti_find(ifp)
struct ifnet *ifp;
{
register struct router_info *rti;
for (rti = rti_head; rti != 0; rti = rti->rti_next) {
if (rti->rti_ifp == ifp)
return (rti);
}
rti = (struct router_info *)malloc(sizeof(struct router_info),
M_MRTABLE, M_NOWAIT);
rti->rti_ifp = ifp;
rti->rti_type = IGMP_v2_ROUTER;
rti->rti_next = rti_head;
rti_head = rti;
return (rti);
}
void
@ -77,18 +103,19 @@ igmp_input(m, iphlen)
register struct mbuf *m;
register int iphlen;
{
register struct igmp *igmp;
register struct ip *ip;
register int igmplen;
register struct ifnet *ifp = m->m_pkthdr.rcvif;
register struct ip *ip = mtod(m, struct ip *);
register struct igmp *igmp;
register int igmplen;
register int minlen;
register struct in_multi *inm;
register struct in_ifaddr *ia;
struct in_multi *inm;
struct in_multistep step;
struct router_info *rti;
register struct in_ifaddr *ia;
int timer;
++igmpstat.igps_rcv_total;
ip = mtod(m, struct ip *);
igmplen = ip->ip_len;
/*
@ -129,32 +156,85 @@ igmp_input(m, iphlen)
if (ifp->if_flags & IFF_LOOPBACK)
break;
if (ip->ip_dst.s_addr != igmp_all_hosts_group) {
++igmpstat.igps_rcv_badqueries;
m_freem(m);
return;
}
if (igmp->igmp_code == 0) {
rti = rti_find(ifp);
rti->rti_type = IGMP_v1_ROUTER;
rti->rti_age = 0;
/*
* Start the timers in all of our membership records for
* the interface on which the query arrived, except those
* that are already running and those that belong to the
* "all-hosts" group.
*/
IN_FIRST_MULTI(step, inm);
while (inm != NULL) {
if (inm->inm_ifp == ifp && inm->inm_timer == 0 &&
inm->inm_addr.s_addr != igmp_all_hosts_group) {
inm->inm_timer =
IGMP_RANDOM_DELAY(inm->inm_addr);
igmp_timers_are_running = 1;
if (ip->ip_dst.s_addr != igmp_all_hosts_group) {
++igmpstat.igps_rcv_badqueries;
m_freem(m);
return;
}
/*
* Start the timers in all of our membership records
* for the interface on which the query arrived,
* except those that are already running and those
* that belong to a "local" group (224.0.0.X).
*/
IN_FIRST_MULTI(step, inm);
while (inm != NULL) {
if (inm->inm_ifp == ifp &&
inm->inm_timer == 0 &&
!IN_LOCAL_GROUP(inm->inm_addr.s_addr)) {
inm->inm_state = IGMP_DELAYING_MEMBER;
inm->inm_timer = IGMP_RANDOM_DELAY(
IGMP_MAX_HOST_REPORT_DELAY * PR_FASTHZ);
igmp_timers_are_running = 1;
}
IN_NEXT_MULTI(step, inm);
}
} else {
if (!IN_MULTICAST(ip->ip_dst.s_addr)) {
++igmpstat.igps_rcv_badqueries;
m_freem(m);
return;
}
timer = igmp->igmp_code * PR_FASTHZ / IGMP_TIMER_SCALE;
/*
* Start the timers in all of our membership records
* for the interface on which the query arrived,
* except those that are already running and those
* that belong to a "local" group (224.0.0.X). For
* timers already running, check if they need to be
* reset.
*/
IN_FIRST_MULTI(step, inm);
while (inm != NULL) {
if (inm->inm_ifp == ifp &&
!IN_LOCAL_GROUP(inm->inm_addr.s_addr) &&
(ip->ip_dst.s_addr == igmp_all_hosts_group ||
ip->ip_dst.s_addr == inm->inm_addr.s_addr)) {
switch (inm->inm_state) {
case IGMP_DELAYING_MEMBER:
if (inm->inm_timer <= timer)
break;
/* FALLTHROUGH */
case IGMP_IDLE_MEMBER:
case IGMP_LAZY_MEMBER:
case IGMP_AWAKENING_MEMBER:
inm->inm_state =
IGMP_DELAYING_MEMBER;
inm->inm_timer =
IGMP_RANDOM_DELAY(timer);
igmp_timers_are_running = 1;
break;
case IGMP_SLEEPING_MEMBER:
inm->inm_state =
IGMP_AWAKENING_MEMBER;
break;
}
}
IN_NEXT_MULTI(step, inm);
}
IN_NEXT_MULTI(step, inm);
}
break;
case IGMP_HOST_MEMBERSHIP_REPORT:
case IGMP_v1_HOST_MEMBERSHIP_REPORT:
++igmpstat.igps_rcv_reports;
if (ifp->if_flags & IFF_LOOPBACK)
@ -171,14 +251,15 @@ igmp_input(m, iphlen)
* KLUDGE: if the IP source address of the report has an
* unspecified (i.e., zero) subnet number, as is allowed for
* a booting host, replace it with the correct subnet number
* so that a process-level multicast routing demon can
* so that a process-level multicast routing daemon can
* determine which subnet it arrived from. This is necessary
* to compensate for the lack of any way for a process to
* determine the arrival interface of an incoming packet.
*/
if ((ntohl(ip->ip_src.s_addr) & IN_CLASSA_NET) == 0) {
IFP_TO_IA(ifp, ia);
if (ia) ip->ip_src.s_addr = htonl(ia->ia_subnet);
if (ia)
ip->ip_src.s_addr = htonl(ia->ia_subnet);
}
/*
@ -189,9 +270,89 @@ igmp_input(m, iphlen)
if (inm != NULL) {
inm->inm_timer = 0;
++igmpstat.igps_rcv_ourreports;
switch (inm->inm_state) {
case IGMP_IDLE_MEMBER:
case IGMP_LAZY_MEMBER:
case IGMP_AWAKENING_MEMBER:
case IGMP_SLEEPING_MEMBER:
inm->inm_state = IGMP_SLEEPING_MEMBER;
break;
case IGMP_DELAYING_MEMBER:
if (inm->inm_rti->rti_type == IGMP_v1_ROUTER)
inm->inm_state = IGMP_LAZY_MEMBER;
else
inm->inm_state = IGMP_SLEEPING_MEMBER;
break;
}
}
break;
case IGMP_v2_HOST_MEMBERSHIP_REPORT:
#ifdef MROUTING
/*
* Make sure we don't hear our own membership report. Fast
* leave requires knowing that we are the only member of a
* group.
*/
IFP_TO_IA(ifp, ia);
if (ia && ip->ip_src.s_addr == IA_SIN(ia)->sin_addr.s_addr)
break;
#endif
++igmpstat.igps_rcv_reports;
if (ifp->if_flags & IFF_LOOPBACK)
break;
if (!IN_MULTICAST(ntohl(igmp->igmp_group.s_addr)) ||
igmp->igmp_group.s_addr != ip->ip_dst.s_addr) {
++igmpstat.igps_rcv_badreports;
m_freem(m);
return;
}
/*
* KLUDGE: if the IP source address of the report has an
* unspecified (i.e., zero) subnet number, as is allowed for
* a booting host, replace it with the correct subnet number
* so that a process-level multicast routing daemon can
* determine which subnet it arrived from. This is necessary
* to compensate for the lack of any way for a process to
* determine the arrival interface of an incoming packet.
*/
if ((ntohl(ip->ip_src.s_addr) & IN_CLASSA_NET) == 0) {
#ifndef MROUTING
IFP_TO_IA(ifp, ia);
#endif
if (ia)
ip->ip_src.s_addr = htonl(ia->ia_subnet);
}
/*
* If we belong to the group being reported, stop
* our timer for that group.
*/
IN_LOOKUP_MULTI(igmp->igmp_group, ifp, inm);
if (inm != NULL) {
inm->inm_timer = 0;
++igmpstat.igps_rcv_ourreports;
switch (inm->inm_state) {
case IGMP_DELAYING_MEMBER:
case IGMP_IDLE_MEMBER:
case IGMP_AWAKENING_MEMBER:
inm->inm_state = IGMP_LAZY_MEMBER;
break;
case IGMP_LAZY_MEMBER:
case IGMP_SLEEPING_MEMBER:
break;
}
}
break;
}
/*
@ -205,16 +366,19 @@ void
igmp_joingroup(inm)
struct in_multi *inm;
{
register int s = splnet();
int s = splnet();
if (inm->inm_addr.s_addr == igmp_all_hosts_group ||
(inm->inm_ifp->if_flags & IFF_LOOPBACK))
inm->inm_timer = 0;
else {
igmp_sendreport(inm);
inm->inm_timer = IGMP_RANDOM_DELAY(inm->inm_addr);
inm->inm_state = IGMP_IDLE_MEMBER;
if (!IN_LOCAL_GROUP(inm->inm_addr.s_addr) &&
(inm->inm_ifp->if_flags & IFF_LOOPBACK) == 0) {
igmp_sendpkt(inm, rti_fill(inm));
inm->inm_state = IGMP_DELAYING_MEMBER;
inm->inm_timer = IGMP_RANDOM_DELAY(
IGMP_MAX_HOST_REPORT_DELAY * PR_FASTHZ);
igmp_timers_are_running = 1;
}
} else
inm->inm_timer = 0;
splx(s);
}
@ -222,17 +386,28 @@ void
igmp_leavegroup(inm)
struct in_multi *inm;
{
/*
* No action required on leaving a group.
*/
switch (inm->inm_state) {
case IGMP_DELAYING_MEMBER:
case IGMP_IDLE_MEMBER:
if (!IN_LOCAL_GROUP(inm->inm_addr.s_addr) &&
(inm->inm_ifp->if_flags & IFF_LOOPBACK) == 0)
if (inm->inm_rti->rti_type != IGMP_v1_ROUTER)
igmp_sendpkt(inm, IGMP_HOST_LEAVE_MESSAGE);
break;
case IGMP_LAZY_MEMBER:
case IGMP_AWAKENING_MEMBER:
case IGMP_SLEEPING_MEMBER:
break;
}
}
void
igmp_fasttimo()
{
register struct in_multi *inm;
register int s;
struct in_multistep step;
int s;
/*
* Quick check to see if any work needs to be done, in order
@ -248,7 +423,15 @@ igmp_fasttimo()
if (inm->inm_timer == 0) {
/* do nothing */
} else if (--inm->inm_timer == 0) {
igmp_sendreport(inm);
if (inm->inm_state == IGMP_DELAYING_MEMBER) {
if (inm->inm_rti->rti_type == IGMP_v1_ROUTER)
igmp_sendpkt(inm,
IGMP_v1_HOST_MEMBERSHIP_REPORT);
else
igmp_sendpkt(inm,
IGMP_v2_HOST_MEMBERSHIP_REPORT);
inm->inm_state = IGMP_IDLE_MEMBER;
}
} else {
igmp_timers_are_running = 1;
}
@ -257,15 +440,34 @@ igmp_fasttimo()
splx(s);
}
static void
igmp_sendreport(inm)
register struct in_multi *inm;
void
igmp_slowtimo()
{
register struct mbuf *m;
register struct igmp *igmp;
register struct ip *ip;
register struct ip_moptions *imo;
struct ip_moptions simo;
register struct router_info *rti;
int s;
s = splnet();
for (rti = rti_head; rti != 0; rti = rti->rti_next) {
if (rti->rti_type == IGMP_v1_ROUTER &&
++rti->rti_age >= IGMP_AGE_THRESHOLD) {
rti->rti_type = IGMP_v2_ROUTER;
}
}
splx(s);
}
void
igmp_sendpkt(inm, type)
struct in_multi *inm;
int type;
{
struct mbuf *m;
struct igmp *igmp;
struct ip *ip;
struct ip_moptions imo;
#ifdef MROUTING
extern struct socket *ip_mrouter;
#endif /* MROUTING */
MGETHDR(m, M_DONTWAIT, MT_HEADER);
if (m == NULL)
@ -289,7 +491,7 @@ igmp_sendreport(inm)
m->m_data += sizeof(struct ip);
m->m_len -= sizeof(struct ip);
igmp = mtod(m, struct igmp *);
igmp->igmp_type = IGMP_HOST_MEMBERSHIP_REPORT;
igmp->igmp_type = type;
igmp->igmp_code = 0;
igmp->igmp_group = inm->inm_addr;
igmp->igmp_cksum = 0;
@ -297,21 +499,23 @@ igmp_sendreport(inm)
m->m_data -= sizeof(struct ip);
m->m_len += sizeof(struct ip);
imo = &simo;
bzero((caddr_t)imo, sizeof(*imo));
imo->imo_multicast_ifp = inm->inm_ifp;
imo->imo_multicast_ttl = 1;
imo.imo_multicast_ifp = inm->inm_ifp;
imo.imo_multicast_ttl = 1;
#ifdef RSVP_ISI
imo.imo_multicast_vif = -1;
#endif
/*
* Request loopback of the report if we are acting as a multicast
* router, so that the process-level routing demon can hear it.
*/
#ifdef MROUTING
{
extern struct socket *ip_mrouter;
imo->imo_multicast_loop = (ip_mrouter != NULL);
}
#endif
ip_output(m, NULL, NULL, 0, imo);
imo.imo_multicast_loop = (ip_mrouter != NULL);
#else
imo.imo_multicast_loop = 0;
#endif /* MROUTING */
ip_output(m, (struct mbuf *)0, (struct route *)0, IP_MULTICASTOPTS,
&imo);
++igmpstat.igps_snd_reports;
}

48
sys/netinet/igmp.h
View File

@ -1,4 +1,4 @@
/* $NetBSD: igmp.h,v 1.5 1995/04/13 06:26:39 cgd Exp $ */
/* $NetBSD: igmp.h,v 1.6 1995/05/31 06:08:21 mycroft Exp $ */
/*
* Copyright (c) 1988 Stephen Deering.
@ -39,24 +39,54 @@
* @(#)igmp.h 8.1 (Berkeley) 6/10/93
*/
/* Internet Group Management Protocol (IGMP) definitions. */
/*
* Internet Group Management Protocol (IGMP) definitions.
*
* MULTICAST 1.3
*/
/*
* IGMP packet format.
*/
struct igmp {
u_int8_t igmp_type; /* version & type of IGMP message */
u_int8_t igmp_code; /* unused, should be zero */
u_int8_t igmp_code; /* code for routing sub-messages */
u_int16_t igmp_cksum; /* IP-style checksum */
struct in_addr igmp_group; /* group address being reported */
}; /* (zero for queries) */
#define IGMP_MINLEN 8
#define IGMP_HOST_MEMBERSHIP_QUERY 0x11 /* message types, incl. version */
#define IGMP_HOST_MEMBERSHIP_REPORT 0x12
#define IGMP_DVMRP 0x13 /* for experimental multicast */
/* routing protocol */
#define IGMP_HOST_MEMBERSHIP_QUERY 0x11 /* membership query */
#define IGMP_v1_HOST_MEMBERSHIP_REPORT 0x12 /* v1 membership report */
#define IGMP_DVMRP 0x13 /* DVMRP routing message */
#define IGMP_PIM 0x14 /* PIM routing message */
#define IGMP_v2_HOST_MEMBERSHIP_REPORT 0x16 /* v2 membership report */
#define IGMP_HOST_LEAVE_MESSAGE 0x17 /* leave-group message */
#define IGMP_MTRACE_REPLY 0x1e /* traceroute reply */
#define IGMP_MTRACE_QUERY 0x1f /* traceroute query */
#define IGMP_MAX_HOST_REPORT_DELAY 10 /* max delay for response to */
/* query (in seconds) */
#define IGMP_MAX_HOST_REPORT_DELAY 10 /* max delay for response to */
/* query (in seconds) */
#define IGMP_TIMER_SCALE 10 /* denominator for igmp_timer */
/*
* States for the IGMP v2 state table.
*/
#define IGMP_DELAYING_MEMBER 1
#define IGMP_IDLE_MEMBER 2
#define IGMP_LAZY_MEMBER 3
#define IGMP_SLEEPING_MEMBER 4
#define IGMP_AWAKENING_MEMBER 5
/*
* States for IGMP router version cache.
*/
#define IGMP_v1_ROUTER 1
#define IGMP_v2_ROUTER 2
/*
* Revert to v2 if we haven't heard from the router in this amount of time.
*/
#define IGMP_AGE_THRESHOLD 540

11
sys/netinet/igmp_var.h
View File

@ -1,4 +1,4 @@
/* $NetBSD: igmp_var.h,v 1.7 1995/03/26 20:32:22 jtc Exp $ */
/* $NetBSD: igmp_var.h,v 1.8 1995/05/31 06:08:24 mycroft Exp $ */
/*
* Copyright (c) 1988 Stephen Deering.
@ -44,8 +44,10 @@
* implementation-specific definitions.
*
* Written by Steve Deering, Stanford, May 1988.
* Modified by Rosen Sharma, Stanford, Aug 1994.
* Modified by Bill Fenner, Xerox PARC, Feb 1995.
*
* MULTICAST 1.1
* MULTICAST 1.3
*/
struct igmpstat {
@ -68,13 +70,12 @@ struct igmpstat igmpstat;
* DELAY * countdown frequency). We assume that the routine random()
* is defined somewhere (and that it returns a positive number).
*/
#define IGMP_RANDOM_DELAY(multiaddr) \
/* struct in_addr multiaddr; */ \
(random() % (IGMP_MAX_HOST_REPORT_DELAY * PR_FASTHZ) + 1)
#define IGMP_RANDOM_DELAY(X) (random() % (X) + 1)
void igmp_init __P((void));
void igmp_input __P((struct mbuf *, int));
void igmp_joingroup __P((struct in_multi *));
void igmp_leavegroup __P((struct in_multi *));
void igmp_fasttimo __P((void));
void igmp_slowtimo __P((void));
#endif

4
sys/netinet/in_proto.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: in_proto.c,v 1.9 1994/06/29 06:38:09 cgd Exp $ */
/* $NetBSD: in_proto.c,v 1.10 1995/05/31 06:08:27 mycroft Exp $ */
/*
* Copyright (c) 1982, 1986, 1993
@ -109,7 +109,7 @@ struct protosw inetsw[] = {
{ SOCK_RAW, &inetdomain, IPPROTO_IGMP, PR_ATOMIC|PR_ADDR,
igmp_input, rip_output, 0, rip_ctloutput,
rip_usrreq,
igmp_init, igmp_fasttimo, 0, 0,
igmp_init, igmp_fasttimo, igmp_slowtimo, 0,
},
#ifdef TPIP
{ SOCK_SEQPACKET,&inetdomain, IPPROTO_TP, PR_CONNREQUIRED|PR_WANTRCVD,

14
sys/netinet/in_var.h
View File

@ -1,4 +1,4 @@
/* $NetBSD: in_var.h,v 1.11 1995/04/13 06:30:32 cgd Exp $ */
/* $NetBSD: in_var.h,v 1.12 1995/05/31 06:08:29 mycroft Exp $ */
/*
* Copyright (c) 1985, 1986, 1993
@ -114,6 +114,16 @@ void in_socktrim __P((struct sockaddr_in *));
}
#endif
/*
* Per-interface router version information.
*/
struct router_info {
struct ifnet *rti_ifp;
int rti_type; /* type of router on this interface */
int rti_age; /* time since last v1 query */
struct router_info *rti_next;
};
/*
* Internet multicast address structure. There is one of these for each IP
* multicast group to which this host belongs on a given network interface.
@ -127,6 +137,8 @@ struct in_multi {
u_int inm_refcount; /* no. membership claims by sockets */
u_int inm_timer; /* IGMP membership report timer */
struct in_multi *inm_next; /* ptr to next multicast address */
u_int inm_state; /* state of membership */
struct router_info *inm_rti; /* router version info */
};
#ifdef _KERNEL