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/* $NetBSD: mld6.c,v 1.53 2011/08/31 18:31:03 plunky Exp $ */
/* $KAME: mld6.c,v 1.25 2001/01/16 14:14:18 itojun Exp $ */
/*
* Copyright (C) 1998 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Stephen Deering of Stanford University.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)igmp.c 8.1 (Berkeley) 7/19/93
*/
/*
* Copyright (c) 1988 Stephen Deering.
*
* This code is derived from software contributed to Berkeley by
* Stephen Deering of Stanford University.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)igmp.c 8.1 (Berkeley) 7/19/93
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: mld6.c,v 1.53 2011/08/31 18:31:03 plunky Exp $");
#include "opt_inet.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/protosw.h>
#include <sys/syslog.h>
#include <sys/sysctl.h>
#include <sys/kernel.h>
#include <sys/callout.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet6/in6_var.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/scope6_var.h>
#include <netinet/icmp6.h>
#include <netinet6/icmp6_private.h>
#include <netinet6/mld6_var.h>
#include <net/net_osdep.h>
/*
* This structure is used to keep track of in6_multi chains which belong to
* deleted interface addresses.
*/
static LIST_HEAD(, multi6_kludge) in6_mk; /* XXX BSS initialization */
struct multi6_kludge {
LIST_ENTRY(multi6_kludge) mk_entry;
struct ifnet *mk_ifp;
struct in6_multihead mk_head;
};
/*
* Protocol constants
*/
/*
* time between repetitions of a node's initial report of interest in a
* multicast address(in seconds)
*/
#define MLD_UNSOLICITED_REPORT_INTERVAL 10
static struct ip6_pktopts ip6_opts;
static void mld_start_listening(struct in6_multi *);
static void mld_stop_listening(struct in6_multi *);
static struct mld_hdr * mld_allocbuf(struct mbuf **, int, struct in6_multi *,
int);
static void mld_sendpkt(struct in6_multi *, int, const struct in6_addr *);
static void mld_starttimer(struct in6_multi *);
static void mld_stoptimer(struct in6_multi *);
static u_long mld_timerresid(struct in6_multi *);
void
mld_init(void)
{
static u_int8_t hbh_buf[8];
struct ip6_hbh *hbh = (struct ip6_hbh *)hbh_buf;
u_int16_t rtalert_code = htons((u_int16_t)IP6OPT_RTALERT_MLD);
/* ip6h_nxt will be fill in later */
hbh->ip6h_len = 0; /* (8 >> 3) - 1 */
/* XXX: grotty hard coding... */
hbh_buf[2] = IP6OPT_PADN; /* 2 byte padding */
hbh_buf[3] = 0;
hbh_buf[4] = IP6OPT_RTALERT;
hbh_buf[5] = IP6OPT_RTALERT_LEN - 2;
memcpy(&hbh_buf[6], (void *)&rtalert_code, sizeof(u_int16_t));
ip6_opts.ip6po_hbh = hbh;
/* We will specify the hoplimit by a multicast option. */
ip6_opts.ip6po_hlim = -1;
}
static void
mld_starttimer(struct in6_multi *in6m)
{
struct timeval now;
microtime(&now);
in6m->in6m_timer_expire.tv_sec = now.tv_sec + in6m->in6m_timer / hz;
in6m->in6m_timer_expire.tv_usec = now.tv_usec +
(in6m->in6m_timer % hz) * (1000000 / hz);
if (in6m->in6m_timer_expire.tv_usec > 1000000) {
in6m->in6m_timer_expire.tv_sec++;
in6m->in6m_timer_expire.tv_usec -= 1000000;
}
/* start or restart the timer */
callout_schedule(&in6m->in6m_timer_ch, in6m->in6m_timer);
}
static void
mld_stoptimer(struct in6_multi *in6m)
{
if (in6m->in6m_timer == IN6M_TIMER_UNDEF)
return;
callout_stop(&in6m->in6m_timer_ch);
in6m->in6m_timer = IN6M_TIMER_UNDEF;
}
static void
mld_timeo(void *arg)
{
struct in6_multi *in6m = arg;
mutex_enter(softnet_lock);
KERNEL_LOCK(1, NULL);
in6m->in6m_timer = IN6M_TIMER_UNDEF;
switch (in6m->in6m_state) {
case MLD_REPORTPENDING:
mld_start_listening(in6m);
break;
default:
mld_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
break;
}
KERNEL_UNLOCK_ONE(NULL);
mutex_exit(softnet_lock);
}
static u_long
mld_timerresid(struct in6_multi *in6m)
{
struct timeval now, diff;
microtime(&now);
if (now.tv_sec > in6m->in6m_timer_expire.tv_sec ||
(now.tv_sec == in6m->in6m_timer_expire.tv_sec &&
now.tv_usec > in6m->in6m_timer_expire.tv_usec)) {
return (0);
}
diff = in6m->in6m_timer_expire;
diff.tv_sec -= now.tv_sec;
diff.tv_usec -= now.tv_usec;
if (diff.tv_usec < 0) {
diff.tv_sec--;
diff.tv_usec += 1000000;
}
/* return the remaining time in milliseconds */
return diff.tv_sec * 1000 + diff.tv_usec / 1000;
}
static void
mld_start_listening(struct in6_multi *in6m)
{
struct in6_addr all_in6;
/*
* RFC2710 page 10:
* The node never sends a Report or Done for the link-scope all-nodes
* address.
* MLD messages are never sent for multicast addresses whose scope is 0
* (reserved) or 1 (node-local).
*/
all_in6 = in6addr_linklocal_allnodes;
if (in6_setscope(&all_in6, in6m->in6m_ifp, NULL)) {
/* XXX: this should not happen! */
in6m->in6m_timer = 0;
in6m->in6m_state = MLD_OTHERLISTENER;
}
if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &all_in6) ||
IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) < IPV6_ADDR_SCOPE_LINKLOCAL) {
in6m->in6m_timer = IN6M_TIMER_UNDEF;
in6m->in6m_state = MLD_OTHERLISTENER;
} else {
mld_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
in6m->in6m_timer = arc4random() %
(MLD_UNSOLICITED_REPORT_INTERVAL * hz);
in6m->in6m_state = MLD_IREPORTEDLAST;
mld_starttimer(in6m);
}
}
static void
mld_stop_listening(struct in6_multi *in6m)
{
struct in6_addr allnode, allrouter;
allnode = in6addr_linklocal_allnodes;
if (in6_setscope(&allnode, in6m->in6m_ifp, NULL)) {
/* XXX: this should not happen! */
return;
}
allrouter = in6addr_linklocal_allrouters;
if (in6_setscope(&allrouter, in6m->in6m_ifp, NULL)) {
/* XXX impossible */
return;
}
if (in6m->in6m_state == MLD_IREPORTEDLAST &&
(!IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &allnode)) &&
IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) >
IPV6_ADDR_SCOPE_INTFACELOCAL) {
mld_sendpkt(in6m, MLD_LISTENER_DONE, &allrouter);
}
}
void
mld_input(struct mbuf *m, int off)
{
struct ip6_hdr *ip6;
struct mld_hdr *mldh;
struct ifnet *ifp = m->m_pkthdr.rcvif;
struct in6_multi *in6m = NULL;
struct in6_addr mld_addr, all_in6;
struct in6_ifaddr *ia;
u_long timer = 0; /* timer value in the MLD query header */
IP6_EXTHDR_GET(mldh, struct mld_hdr *, m, off, sizeof(*mldh));
if (mldh == NULL) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
return;
}
/* source address validation */
ip6 = mtod(m, struct ip6_hdr *);/* in case mpullup */
if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) {
/*
* RFC3590 allows the IPv6 unspecified address as the source
* address of MLD report and done messages. However, as this
* same document says, this special rule is for snooping
* switches and the RFC requires routers to discard MLD packets
* with the unspecified source address. The RFC only talks
* about hosts receiving an MLD query or report in Security
* Considerations, but this is probably the correct intention.
* RFC3590 does not talk about other cases than link-local and
* the unspecified source addresses, but we believe the same
* rule should be applied.
* As a result, we only allow link-local addresses as the
* source address; otherwise, simply discard the packet.
*/
#if 0
/*
* XXX: do not log in an input path to avoid log flooding,
* though RFC3590 says "SHOULD log" if the source of a query
* is the unspecified address.
*/
log(LOG_INFO,
"mld_input: src %s is not link-local (grp=%s)\n",
ip6_sprintf(&ip6->ip6_src), ip6_sprintf(&mldh->mld_addr));
#endif
m_freem(m);
return;
}
/*
* make a copy for local work (in6_setscope() may modify the 1st arg)
*/
mld_addr = mldh->mld_addr;
if (in6_setscope(&mld_addr, ifp, NULL)) {
/* XXX: this should not happen! */
m_free(m);
return;
}
/*
* In the MLD specification, there are 3 states and a flag.
*
* In Non-Listener state, we simply don't have a membership record.
* In Delaying Listener state, our timer is running (in6m->in6m_timer)
* In Idle Listener state, our timer is not running
* (in6m->in6m_timer==IN6M_TIMER_UNDEF)
*
* The flag is in6m->in6m_state, it is set to MLD_OTHERLISTENER if
* we have heard a report from another member, or MLD_IREPORTEDLAST
* if we sent the last report.
*/
switch (mldh->mld_type) {
case MLD_LISTENER_QUERY:
if (ifp->if_flags & IFF_LOOPBACK)
break;
if (!IN6_IS_ADDR_UNSPECIFIED(&mld_addr) &&
!IN6_IS_ADDR_MULTICAST(&mld_addr))
break; /* print error or log stat? */
all_in6 = in6addr_linklocal_allnodes;
if (in6_setscope(&all_in6, ifp, NULL)) {
/* XXX: this should not happen! */
break;
}
/*
* - Start the timers in all of our membership records
* that the query applies to for the interface on
* which the query arrived excl. those that belong
* to the "all-nodes" group (ff02::1).
* - Restart any timer that is already running but has
* a value longer than the requested timeout.
* - Use the value specified in the query message as
* the maximum timeout.
*/
timer = ntohs(mldh->mld_maxdelay);
IFP_TO_IA6(ifp, ia);
if (ia == NULL)
break;
LIST_FOREACH(in6m, &ia->ia6_multiaddrs, in6m_entry) {
if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &all_in6) ||
IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) <
IPV6_ADDR_SCOPE_LINKLOCAL)
continue;
if (in6m->in6m_state == MLD_REPORTPENDING)
continue; /* we are not yet ready */
if (!IN6_IS_ADDR_UNSPECIFIED(&mld_addr) &&
!IN6_ARE_ADDR_EQUAL(&mld_addr, &in6m->in6m_addr))
continue;
if (timer == 0) {
/* send a report immediately */
mld_stoptimer(in6m);
mld_sendpkt(in6m, MLD_LISTENER_REPORT, NULL);
in6m->in6m_state = MLD_IREPORTEDLAST;
} else if (in6m->in6m_timer == IN6M_TIMER_UNDEF ||
mld_timerresid(in6m) > timer) {
in6m->in6m_timer =
1 + (arc4random() % timer) * hz / 1000;
mld_starttimer(in6m);
}
}
break;
case MLD_LISTENER_REPORT:
/*
* For fast leave to work, we have to know that we are the
* last person to send a report for this group. Reports
* can potentially get looped back if we are a multicast
* router, so discard reports sourced by me.
* Note that it is impossible to check IFF_LOOPBACK flag of
* ifp for this purpose, since ip6_mloopback pass the physical
* interface to looutput.
*/
if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */
break;
if (!IN6_IS_ADDR_MULTICAST(&mldh->mld_addr))
break;
/*
* If we belong to the group being reported, stop
* our timer for that group.
*/
IN6_LOOKUP_MULTI(mld_addr, ifp, in6m);
if (in6m) {
mld_stoptimer(in6m); /* transit to idle state */
in6m->in6m_state = MLD_OTHERLISTENER; /* clear flag */
}
break;
default: /* this is impossible */
#if 0
/*
* this case should be impossible because of filtering in
* icmp6_input(). But we explicitly disabled this part
* just in case.
*/
log(LOG_ERR, "mld_input: illegal type(%d)", mldh->mld_type);
#endif
break;
}
m_freem(m);
}
static void
mld_sendpkt(struct in6_multi *in6m, int type,
const struct in6_addr *dst)
{
struct mbuf *mh;
struct mld_hdr *mldh;
struct ip6_hdr *ip6 = NULL;
struct ip6_moptions im6o;
struct in6_ifaddr *ia = NULL;
struct ifnet *ifp = in6m->in6m_ifp;
int ignflags;
/*
* At first, find a link local address on the outgoing interface
* to use as the source address of the MLD packet.
* We do not reject tentative addresses for MLD report to deal with
* the case where we first join a link-local address.
*/
ignflags = (IN6_IFF_NOTREADY|IN6_IFF_ANYCAST) & ~IN6_IFF_TENTATIVE;
if ((ia = in6ifa_ifpforlinklocal(ifp, ignflags)) == NULL)
return;
if ((ia->ia6_flags & IN6_IFF_TENTATIVE))
ia = NULL;
/* Allocate two mbufs to store IPv6 header and MLD header */
mldh = mld_allocbuf(&mh, sizeof(struct mld_hdr), in6m, type);
if (mldh == NULL)
return;
/* fill src/dst here */
ip6 = mtod(mh, struct ip6_hdr *);
ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
ip6->ip6_dst = dst ? *dst : in6m->in6m_addr;
mldh->mld_addr = in6m->in6m_addr;
in6_clearscope(&mldh->mld_addr); /* XXX */
mldh->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6, sizeof(struct ip6_hdr),
sizeof(struct mld_hdr));
/* construct multicast option */
memset(&im6o, 0, sizeof(im6o));
im6o.im6o_multicast_ifp = ifp;
im6o.im6o_multicast_hlim = 1;
/*
* Request loopback of the report if we are acting as a multicast
* router, so that the process-level routing daemon can hear it.
*/
im6o.im6o_multicast_loop = (ip6_mrouter != NULL);
/* increment output statictics */
ICMP6_STATINC(ICMP6_STAT_OUTHIST + type);
icmp6_ifstat_inc(ifp, ifs6_out_msg);
switch (type) {
case MLD_LISTENER_QUERY:
icmp6_ifstat_inc(ifp, ifs6_out_mldquery);
break;
case MLD_LISTENER_REPORT:
icmp6_ifstat_inc(ifp, ifs6_out_mldreport);
break;
case MLD_LISTENER_DONE:
icmp6_ifstat_inc(ifp, ifs6_out_mlddone);
break;
}
ip6_output(mh, &ip6_opts, NULL, ia ? 0 : IPV6_UNSPECSRC,
&im6o, NULL, NULL);
}
static struct mld_hdr *
mld_allocbuf(struct mbuf **mh, int len, struct in6_multi *in6m,
int type)
{
struct mbuf *md;
struct mld_hdr *mldh;
struct ip6_hdr *ip6;
/*
* Allocate mbufs to store ip6 header and MLD header.
* We allocate 2 mbufs and make chain in advance because
* it is more convenient when inserting the hop-by-hop option later.
*/
MGETHDR(*mh, M_DONTWAIT, MT_HEADER);
if (*mh == NULL)
return NULL;
MGET(md, M_DONTWAIT, MT_DATA);
if (md == NULL) {
m_free(*mh);
*mh = NULL;
return NULL;
}
(*mh)->m_next = md;
md->m_next = NULL;
(*mh)->m_pkthdr.rcvif = NULL;
(*mh)->m_pkthdr.len = sizeof(struct ip6_hdr) + len;
(*mh)->m_len = sizeof(struct ip6_hdr);
MH_ALIGN(*mh, sizeof(struct ip6_hdr));
/* fill in the ip6 header */
ip6 = mtod(*mh, struct ip6_hdr *);
memset(ip6, 0, sizeof(*ip6));
ip6->ip6_flow = 0;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
/* ip6_plen will be set later */
ip6->ip6_nxt = IPPROTO_ICMPV6;
/* ip6_hlim will be set by im6o.im6o_multicast_hlim */
/* ip6_src/dst will be set by mld_sendpkt() or mld_sendbuf() */
/* fill in the MLD header as much as possible */
md->m_len = len;
mldh = mtod(md, struct mld_hdr *);
memset(mldh, 0, len);
mldh->mld_type = type;
return mldh;
}
/*
* Add an address to the list of IP6 multicast addresses for a given interface.
*/
struct in6_multi *
in6_addmulti(struct in6_addr *maddr6, struct ifnet *ifp,
int *errorp, int timer)
{
struct in6_ifaddr *ia;
struct in6_ifreq ifr;
struct in6_multi *in6m;
int s = splsoftnet();
*errorp = 0;
/*
* See if address already in list.
*/
IN6_LOOKUP_MULTI(*maddr6, ifp, in6m);
if (in6m != NULL) {
/*
* Found it; just increment the refrence count.
*/
in6m->in6m_refcount++;
} else {
/*
* New address; allocate a new multicast record
* and link it into the interface's multicast list.
*/
in6m = (struct in6_multi *)
malloc(sizeof(*in6m), M_IPMADDR, M_NOWAIT|M_ZERO);
if (in6m == NULL) {
splx(s);
*errorp = ENOBUFS;
return (NULL);
}
in6m->in6m_addr = *maddr6;
in6m->in6m_ifp = ifp;
in6m->in6m_refcount = 1;
in6m->in6m_timer = IN6M_TIMER_UNDEF;
IFP_TO_IA6(ifp, ia);
if (ia == NULL) {
free(in6m, M_IPMADDR);
splx(s);
*errorp = EADDRNOTAVAIL; /* appropriate? */
return (NULL);
}
in6m->in6m_ia = ia;
IFAREF(&ia->ia_ifa); /* gain a reference */
LIST_INSERT_HEAD(&ia->ia6_multiaddrs, in6m, in6m_entry);
/*
* Ask the network driver to update its multicast reception
* filter appropriately for the new address.
*/
sockaddr_in6_init(&ifr.ifr_addr, maddr6, 0, 0, 0);
*errorp = (*ifp->if_ioctl)(ifp, SIOCADDMULTI, &ifr);
if (*errorp) {
LIST_REMOVE(in6m, in6m_entry);
free(in6m, M_IPMADDR);
IFAFREE(&ia->ia_ifa);
splx(s);
return (NULL);
}
callout_init(&in6m->in6m_timer_ch, CALLOUT_MPSAFE);
callout_setfunc(&in6m->in6m_timer_ch, mld_timeo, in6m);
in6m->in6m_timer = timer;
if (in6m->in6m_timer > 0) {
in6m->in6m_state = MLD_REPORTPENDING;
mld_starttimer(in6m);
splx(s);
return (in6m);
}
/*
* Let MLD6 know that we have joined a new IP6 multicast
* group.
*/
mld_start_listening(in6m);
}
splx(s);
return (in6m);
}
/*
* Delete a multicast address record.
*/
void
in6_delmulti(struct in6_multi *in6m)
{
struct in6_ifreq ifr;
struct in6_ifaddr *ia;
int s = splsoftnet();
mld_stoptimer(in6m);
if (--in6m->in6m_refcount == 0) {
/*
* No remaining claims to this record; let MLD6 know
* that we are leaving the multicast group.
*/
mld_stop_listening(in6m);
/*
* Unlink from list.
*/
LIST_REMOVE(in6m, in6m_entry);
if (in6m->in6m_ia != NULL) {
IFAFREE(&in6m->in6m_ia->ia_ifa); /* release reference */
in6m->in6m_ia = NULL;
}
/*
* Delete all references of this multicasting group from
* the membership arrays
*/
for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
struct in6_multi_mship *imm;
LIST_FOREACH(imm, &ia->ia6_memberships, i6mm_chain) {
if (imm->i6mm_maddr == in6m)
imm->i6mm_maddr = NULL;
}
}
/*
* Notify the network driver to update its multicast
* reception filter.
*/
sockaddr_in6_init(&ifr.ifr_addr, &in6m->in6m_addr, 0, 0, 0);
(*in6m->in6m_ifp->if_ioctl)(in6m->in6m_ifp, SIOCDELMULTI, &ifr);
callout_destroy(&in6m->in6m_timer_ch);
free(in6m, M_IPMADDR);
}
splx(s);
}
struct in6_multi_mship *
in6_joingroup(struct ifnet *ifp, struct in6_addr *addr,
int *errorp, int timer)
{
struct in6_multi_mship *imm;
imm = malloc(sizeof(*imm), M_IPMADDR, M_NOWAIT|M_ZERO);
if (imm == NULL) {
*errorp = ENOBUFS;
return NULL;
}
imm->i6mm_maddr = in6_addmulti(addr, ifp, errorp, timer);
if (!imm->i6mm_maddr) {
/* *errorp is already set */
free(imm, M_IPMADDR);
return NULL;
}
return imm;
}
int
in6_leavegroup(struct in6_multi_mship *imm)
{
if (imm->i6mm_maddr) {
in6_delmulti(imm->i6mm_maddr);
}
free(imm, M_IPMADDR);
return 0;
}
/*
* Multicast address kludge:
* If there were any multicast addresses attached to this interface address,
* either move them to another address on this interface, or save them until
* such time as this interface is reconfigured for IPv6.
*/
void
in6_savemkludge(struct in6_ifaddr *oia)
{
struct in6_ifaddr *ia;
struct in6_multi *in6m;
IFP_TO_IA6(oia->ia_ifp, ia);
if (ia) { /* there is another address */
KASSERT(ia != oia);
while ((in6m = LIST_FIRST(&oia->ia6_multiaddrs)) != NULL) {
LIST_REMOVE(in6m, in6m_entry);
IFAREF(&ia->ia_ifa);
IFAFREE(&in6m->in6m_ia->ia_ifa);
in6m->in6m_ia = ia;
LIST_INSERT_HEAD(&ia->ia6_multiaddrs, in6m, in6m_entry);
}
} else { /* last address on this if deleted, save */
struct multi6_kludge *mk;
LIST_FOREACH(mk, &in6_mk, mk_entry) {
if (mk->mk_ifp == oia->ia_ifp)
break;
}
if (mk == NULL) /* this should not happen! */
panic("in6_savemkludge: no kludge space");
while ((in6m = LIST_FIRST(&oia->ia6_multiaddrs)) != NULL) {
LIST_REMOVE(in6m, in6m_entry);
IFAFREE(&in6m->in6m_ia->ia_ifa); /* release reference */
in6m->in6m_ia = NULL;
LIST_INSERT_HEAD(&mk->mk_head, in6m, in6m_entry);
}
}
}
/*
* Continuation of multicast address hack:
* If there was a multicast group list previously saved for this interface,
* then we re-attach it to the first address configured on the i/f.
*/
void
in6_restoremkludge(struct in6_ifaddr *ia, struct ifnet *ifp)
{
struct multi6_kludge *mk;
struct in6_multi *in6m;
LIST_FOREACH(mk, &in6_mk, mk_entry) {
if (mk->mk_ifp == ifp)
break;
}
if (mk == NULL)
return;
while ((in6m = LIST_FIRST(&mk->mk_head)) != NULL) {
LIST_REMOVE(in6m, in6m_entry);
in6m->in6m_ia = ia;
IFAREF(&ia->ia_ifa);
LIST_INSERT_HEAD(&ia->ia6_multiaddrs, in6m, in6m_entry);
}
}
/*
* Allocate space for the kludge at interface initialization time.
* Formerly, we dynamically allocated the space in in6_savemkludge() with
* malloc(M_WAITOK). However, it was wrong since the function could be called
* under an interrupt context (software timer on address lifetime expiration).
* Also, we cannot just give up allocating the strucutre, since the group
* membership structure is very complex and we need to keep it anyway.
* Of course, this function MUST NOT be called under an interrupt context.
* Specifically, it is expected to be called only from in6_ifattach(), though
* it is a global function.
*/
void
in6_createmkludge(struct ifnet *ifp)
{
struct multi6_kludge *mk;
LIST_FOREACH(mk, &in6_mk, mk_entry) {
/* If we've already had one, do not allocate. */
if (mk->mk_ifp == ifp)
return;
}
mk = malloc(sizeof(*mk), M_IPMADDR, M_ZERO|M_WAITOK);
LIST_INIT(&mk->mk_head);
mk->mk_ifp = ifp;
LIST_INSERT_HEAD(&in6_mk, mk, mk_entry);
}
void
in6_purgemkludge(struct ifnet *ifp)
{
struct multi6_kludge *mk;
struct in6_multi *in6m, *next;
LIST_FOREACH(mk, &in6_mk, mk_entry) {
if (mk->mk_ifp == ifp)
break;
}
if (mk == NULL)
return;
/* leave from all multicast groups joined */
for (in6m = LIST_FIRST(&mk->mk_head); in6m != NULL; in6m = next) {
next = LIST_NEXT(in6m, in6m_entry);
in6_delmulti(in6m);
}
LIST_REMOVE(mk, mk_entry);
free(mk, M_IPMADDR);
}
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