/*
* 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
*/
/*
* time between repetitions of a node's initial report of interest in a
* multicast address(in seconds)
*/
#define MLD_UNSOLICITED_REPORT_INTERVAL 10
ip6_opts.ip6po_hbh = hbh;
/* We will specify the hoplimit by a multicast option. */
ip6_opts.ip6po_hlim = -1;
ip6_opts.ip6po_prefer_tempaddr = IP6PO_TEMPADDR_NOTPREFER;
/* start or restart the timer */
callout_schedule(&in6m->in6m_timer_ch, in6m->in6m_timer);
}
/*
* mld_stoptimer releases in6_multilock when calling callout_halt.
* The caller must ensure in6m won't be freed while releasing the lock.
*/
static void
mld_stoptimer(struct in6_multi *in6m)
{
ifp = m_get_rcvif_psref(m, &psref);
if (__predict_false(ifp == NULL))
goto out;
IP6_EXTHDR_GET(mldh, struct mld_hdr *, m, off, sizeof(*mldh));
if (mldh == NULL) {
ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
goto out_nodrop;
}
ip6 = mtod(m, struct ip6_hdr *);
/* source address validation */
if (!IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) {
/*
* RFC3590 allows the IPv6 unspecified address as the source
* address of MLD report and done messages. However, as this
* same document says, this special rule is for snooping
* switches and the RFC requires routers to discard MLD packets
* with the unspecified source address. The RFC only talks
* about hosts receiving an MLD query or report in Security
* Considerations, but this is probably the correct intention.
* RFC3590 does not talk about other cases than link-local and
* the unspecified source addresses, but we believe the same
* rule should be applied.
* As a result, we only allow link-local addresses as the
* source address; otherwise, simply discard the packet.
*/
#if 0
/*
* XXX: do not log in an input path to avoid log flooding,
* though RFC3590 says "SHOULD log" if the source of a query
* is the unspecified address.
*/
char ip6bufs[INET6_ADDRSTRLEN];
char ip6bufm[INET6_ADDRSTRLEN];
log(LOG_INFO,
"mld_input: src %s is not link-local (grp=%s)\n",
IN6_PRINT(ip6bufs,&ip6->ip6_src),
IN6_PRINT(ip6bufm, &mldh->mld_addr));
#endif
goto out;
}
/*
* make a copy for local work (in6_setscope() may modify the 1st arg)
*/
mld_addr = mldh->mld_addr;
if (in6_setscope(&mld_addr, ifp, NULL)) {
/* XXX: this should not happen! */
goto out;
}
/*
* In the MLD specification, there are 3 states and a flag.
*
* In Non-Listener state, we simply don't have a membership record.
* In Delaying Listener state, our timer is running (in6m->in6m_timer)
* In Idle Listener state, our timer is not running
* (in6m->in6m_timer==IN6M_TIMER_UNDEF)
*
* The flag is in6m->in6m_state, it is set to MLD_OTHERLISTENER if
* we have heard a report from another member, or MLD_IREPORTEDLAST
* if we sent the last report.
*/
switch (mldh->mld_type) {
case MLD_LISTENER_QUERY: {
struct in6_multi *next;
if (ifp->if_flags & IFF_LOOPBACK)
break;
if (!IN6_IS_ADDR_UNSPECIFIED(&mld_addr) &&
!IN6_IS_ADDR_MULTICAST(&mld_addr))
break; /* print error or log stat? */
all_in6 = in6addr_linklocal_allnodes;
if (in6_setscope(&all_in6, ifp, NULL)) {
/* XXX: this should not happen! */
break;
}
/*
* - Start the timers in all of our membership records
* that the query applies to for the interface on
* which the query arrived excl. those that belong
* to the "all-nodes" group (ff02::1).
* - Restart any timer that is already running but has
* a value longer than the requested timeout.
* - Use the value specified in the query message as
* the maximum timeout.
*/
timer = ntohs(mldh->mld_maxdelay);
rw_enter(&in6_multilock, RW_WRITER);
/*
* mld_stoptimer and mld_sendpkt release in6_multilock
* temporarily, so we have to prevent in6m from being freed
* while releasing the lock by having an extra reference to it.
*
* Also in6_purge_multi might remove items from the list of the
* ifp while releasing the lock. Fortunately in6_purge_multi is
* never executed as long as we have a psref of the ifp.
*/
LIST_FOREACH_SAFE(in6m, &ifp->if_multiaddrs, in6m_entry, next) {
if (IN6_ARE_ADDR_EQUAL(&in6m->in6m_addr, &all_in6) ||
IPV6_ADDR_MC_SCOPE(&in6m->in6m_addr) <
IPV6_ADDR_SCOPE_LINKLOCAL)
continue;
if (in6m->in6m_state == MLD_REPORTPENDING)
continue; /* we are not yet ready */
if (!IN6_IS_ADDR_UNSPECIFIED(&mld_addr) &&
!IN6_ARE_ADDR_EQUAL(&mld_addr, &in6m->in6m_addr))
continue;
case MLD_LISTENER_REPORT:
/*
* For fast leave to work, we have to know that we are the
* last person to send a report for this group. Reports
* can potentially get looped back if we are a multicast
* router, so discard reports sourced by me.
* Note that it is impossible to check IFF_LOOPBACK flag of
* ifp for this purpose, since ip6_mloopback pass the physical
* interface to looutput.
*/
if (m->m_flags & M_LOOP) /* XXX: grotty flag, but efficient */
break;
if (!IN6_IS_ADDR_MULTICAST(&mldh->mld_addr))
break;
/*
* If we belong to the group being reported, stop
* our timer for that group.
*/
rw_enter(&in6_multilock, RW_WRITER);
in6m = in6_lookup_multi(&mld_addr, ifp);
if (in6m) {
in6m_ref(in6m);
mld_stoptimer(in6m); /* transit to idle state */
in6m->in6m_state = MLD_OTHERLISTENER; /* clear flag */
in6m_unref(in6m);
in6m = NULL; /* in6m might be freed */
}
rw_exit(&in6_multilock);
break;
default: /* this is impossible */
#if 0
/*
* this case should be impossible because of filtering in
* icmp6_input(). But we explicitly disabled this part
* just in case.
*/
log(LOG_ERR, "mld_input: illegal type(%d)", mldh->mld_type);
#endif
break;
}
/*
* XXX mld_sendpkt must be called with in6_multilock held and
* will release in6_multilock before calling ip6_output and
* returning to avoid locking against myself in ip6_output.
*/
static void
mld_sendpkt(struct in6_multi *in6m, int type, const struct in6_addr *dst)
{
struct mbuf *mh;
struct mld_hdr *mldh;
struct ip6_hdr *ip6 = NULL;
struct ip6_moptions im6o;
struct in6_ifaddr *ia = NULL;
struct ifnet *ifp = in6m->in6m_ifp;
int ignflags;
struct psref psref;
int bound;
KASSERT(rw_write_held(&in6_multilock));
/*
* At first, find a link local address on the outgoing interface
* to use as the source address of the MLD packet.
* We do not reject tentative addresses for MLD report to deal with
* the case where we first join a link-local address.
*/
ignflags = (IN6_IFF_NOTREADY|IN6_IFF_ANYCAST) & ~IN6_IFF_TENTATIVE;
bound = curlwp_bind();
ia = in6ifa_ifpforlinklocal_psref(ifp, ignflags, &psref);
if (ia == NULL) {
curlwp_bindx(bound);
return;
}
if ((ia->ia6_flags & IN6_IFF_TENTATIVE)) {
ia6_release(ia, &psref);
ia = NULL;
}
/* Allocate two mbufs to store IPv6 header and MLD header */
mldh = mld_allocbuf(&mh, in6m, type);
if (mldh == NULL) {
ia6_release(ia, &psref);
curlwp_bindx(bound);
return;
}
/* fill src/dst here */
ip6 = mtod(mh, struct ip6_hdr *);
ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
ip6->ip6_dst = dst ? *dst : in6m->in6m_addr;
ia6_release(ia, &psref);
curlwp_bindx(bound);
/*
* 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 statistics */
ICMP6_STATINC(ICMP6_STAT_OUTHIST + type);
icmp6_ifstat_inc(ifp, ifs6_out_msg);
switch (type) {
case MLD_LISTENER_QUERY:
icmp6_ifstat_inc(ifp, ifs6_out_mldquery);
break;
case MLD_LISTENER_REPORT:
icmp6_ifstat_inc(ifp, ifs6_out_mldreport);
break;
case MLD_LISTENER_DONE:
icmp6_ifstat_inc(ifp, ifs6_out_mlddone);
break;
}
/* XXX we cannot call ip6_output with holding in6_multilock */
rw_exit(&in6_multilock);
/*
* 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;
/* 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 = sizeof(struct mld_hdr);
mldh = mtod(md, struct mld_hdr *);
memset(mldh, 0, sizeof(struct mld_hdr));
mldh->mld_type = type;
return mldh;
}
KASSERT(rw_write_held(&in6_multilock));
if (--in6m->in6m_refcount == 0)
in6m_destroy(in6m);
}
/*
* Add an address to the list of IP6 multicast addresses for a given interface.
*/
struct in6_multi *
in6_addmulti(struct in6_addr *maddr6, struct ifnet *ifp, int *errorp,
int timer)
{
struct sockaddr_in6 sin6;
struct in6_multi *in6m;
*errorp = 0;
rw_enter(&in6_multilock, RW_WRITER);
/*
* See if address already in list.
*/
in6m = in6_lookup_multi(maddr6, ifp);
if (in6m != NULL) {
/*
* Found it; just increment the reference count.
*/
in6m->in6m_refcount++;
} else {
/*
* New address; allocate a new multicast record
* and link it into the interface's multicast list.
*/
in6m = malloc(sizeof(*in6m), M_IPMADDR, M_NOWAIT|M_ZERO);
if (in6m == NULL) {
*errorp = ENOBUFS;
goto out;
}
/*
* Unlink from list if it's listed. This must be done before
* mld_stop_listening because it releases in6_multilock and that allows
* someone to look up the removing in6m from the list and add a
* reference to the entry unexpectedly.
*/
if (in6_lookup_multi(&in6m->in6m_addr, in6m->in6m_ifp) != NULL)
LIST_REMOVE(in6m, in6m_entry);
/*
* No remaining claims to this record; let MLD6 know
* that we are leaving the multicast group.
*/
mld_stop_listening(in6m);
/*
* Delete all references of this multicasting group from
* the membership arrays
*/
in6_purge_mcast_references(in6m);
/*
* Notify the network driver to update its multicast
* reception filter.
*/
sockaddr_in6_init(&sin6, &in6m->in6m_addr, 0, 0, 0);
if_mcast_op(in6m->in6m_ifp, SIOCDELMULTI, sin6tosa(&sin6));
/*
* The caller should have a reference to in6m. So we don't need to care
* of releasing the lock in mld_stoptimer.
*/
mld_stoptimer(in6m);
if (--in6m->in6m_refcount == 0)
in6m_destroy(in6m);
}
/*
* Look up the in6_multi record for a given IP6 multicast address
* on a given interface. If no matching record is found, "in6m"
* returns NULL.
*/
struct in6_multi *
in6_lookup_multi(const struct in6_addr *addr, const struct ifnet *ifp)
{
struct in6_multi *in6m;
/*
* Purge in6_multi records associated to the interface.
*/
void
in6_purge_multi(struct ifnet *ifp)
{
struct in6_multi *in6m, *next;
rw_enter(&in6_multilock, RW_WRITER);
LIST_FOREACH_SAFE(in6m, &ifp->if_multiaddrs, in6m_entry, next) {
LIST_REMOVE(in6m, in6m_entry);
/*
* Normally multicast addresses are already purged at this
* point. Remaining references aren't accessible via ifp,
* so what we can do here is to prevent ifp from being
* accessed via in6m by removing it from the list of ifp.
*/
mld_stoptimer(in6m);
}
rw_exit(&in6_multilock);
}
void
in6_multi_lock(int op)
{
rw_enter(&in6_multilock, op);
}
void
in6_multi_unlock(void)
{
rw_exit(&in6_multilock);
}
bool
in6_multi_locked(int op)
{
switch (op) {
case RW_READER:
return rw_read_held(&in6_multilock);
case RW_WRITER:
return rw_write_held(&in6_multilock);
default:
return rw_lock_held(&in6_multilock);
}
}
struct in6_multi_mship *
in6_joingroup(struct ifnet *ifp, struct in6_addr *addr, int *errorp, int timer)
{
struct in6_multi_mship *imm;
