gems-kernel/source/THIRDPARTY/xnu/bsd/netinet6/mld6.c
2024-06-03 11:29:39 -05:00

3900 lines
106 KiB
C

/*
* Copyright (c) 2000-2020 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*-
* Copyright (c) 2009 Bruce Simpson.
*
* 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. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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) 1988 Stephen Deering.
* 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. 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
*/
/*
* NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
* support for mandatory and extensible security protections. This notice
* is included in support of clause 2.2 (b) of the Apple Public License,
* Version 2.0.
*/
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/protosw.h>
#include <sys/sysctl.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mcache.h>
#include <dev/random/randomdev.h>
#include <kern/zalloc.h>
#include <net/if.h>
#include <net/route.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/mld6.h>
#include <netinet6/mld6_var.h>
#include <os/log.h>
/* Lock group and attribute for mld_mtx */
static LCK_ATTR_DECLARE(mld_mtx_attr, 0, 0);
static LCK_GRP_DECLARE(mld_mtx_grp, "mld_mtx");
/*
* Locking and reference counting:
*
* mld_mtx mainly protects mli_head. In cases where both mld_mtx and
* in6_multihead_lock must be held, the former must be acquired first in order
* to maintain lock ordering. It is not a requirement that mld_mtx be
* acquired first before in6_multihead_lock, but in case both must be acquired
* in succession, the correct lock ordering must be followed.
*
* Instead of walking the if_multiaddrs list at the interface and returning
* the ifma_protospec value of a matching entry, we search the global list
* of in6_multi records and find it that way; this is done with in6_multihead
* lock held. Doing so avoids the race condition issues that many other BSDs
* suffer from (therefore in our implementation, ifma_protospec will never be
* NULL for as long as the in6_multi is valid.)
*
* The above creates a requirement for the in6_multi to stay in in6_multihead
* list even after the final MLD leave (in MLDv2 mode) until no longer needs
* be retransmitted (this is not required for MLDv1.) In order to handle
* this, the request and reference counts of the in6_multi are bumped up when
* the state changes to MLD_LEAVING_MEMBER, and later dropped in the timeout
* handler. Each in6_multi holds a reference to the underlying mld_ifinfo.
*
* Thus, the permitted lock order is:
*
* mld_mtx, in6_multihead_lock, inm6_lock, mli_lock
*
* Any may be taken independently, but if any are held at the same time,
* the above lock order must be followed.
*/
static LCK_MTX_DECLARE_ATTR(mld_mtx, &mld_mtx_grp, &mld_mtx_attr);
SLIST_HEAD(mld_in6m_relhead, in6_multi);
static void mli_initvar(struct mld_ifinfo *, struct ifnet *, int);
static struct mld_ifinfo *mli_alloc(zalloc_flags_t);
static void mli_free(struct mld_ifinfo *);
static void mli_delete(const struct ifnet *, struct mld_in6m_relhead *);
static void mld_dispatch_packet(struct mbuf *);
static void mld_final_leave(struct in6_multi *, struct mld_ifinfo *,
struct mld_tparams *);
static int mld_handle_state_change(struct in6_multi *, struct mld_ifinfo *,
struct mld_tparams *);
static int mld_initial_join(struct in6_multi *, struct mld_ifinfo *,
struct mld_tparams *, const int);
#ifdef MLD_DEBUG
static const char * mld_rec_type_to_str(const int);
#endif
static uint32_t mld_set_version(struct mld_ifinfo *, const int);
static void mld_append_relq(struct mld_ifinfo *, struct in6_multi *);
static void mld_flush_relq(struct mld_ifinfo *, struct mld_in6m_relhead *);
static void mld_dispatch_queue_locked(struct mld_ifinfo *, struct ifqueue *, int);
static int mld_v1_input_query(struct ifnet *, const struct ip6_hdr *,
/*const*/ struct mld_hdr *);
static int mld_v1_input_report(struct ifnet *, struct mbuf *,
const struct ip6_hdr *, /*const*/ struct mld_hdr *);
static void mld_v1_process_group_timer(struct in6_multi *, const int);
static void mld_v1_process_querier_timers(struct mld_ifinfo *);
static int mld_v1_transmit_report(struct in6_multi *, const uint8_t);
static uint32_t mld_v1_update_group(struct in6_multi *, const int);
static void mld_v2_cancel_link_timers(struct mld_ifinfo *);
static uint32_t mld_v2_dispatch_general_query(struct mld_ifinfo *);
static struct mbuf *
mld_v2_encap_report(struct ifnet *, struct mbuf *);
static int mld_v2_enqueue_filter_change(struct ifqueue *,
struct in6_multi *);
static int mld_v2_enqueue_group_record(struct ifqueue *,
struct in6_multi *, const int, const int, const int,
const int);
static int mld_v2_input_query(struct ifnet *, const struct ip6_hdr *,
struct mbuf *, const int, const int);
static int mld_v2_merge_state_changes(struct in6_multi *,
struct ifqueue *);
static void mld_v2_process_group_timers(struct mld_ifinfo *,
struct ifqueue *, struct ifqueue *,
struct in6_multi *, const int);
static int mld_v2_process_group_query(struct in6_multi *,
int, struct mbuf *, const int);
static int sysctl_mld_gsr SYSCTL_HANDLER_ARGS;
static int sysctl_mld_ifinfo SYSCTL_HANDLER_ARGS;
static int sysctl_mld_v2enable SYSCTL_HANDLER_ARGS;
static const uint32_t mld_timeout_delay = 1000; /* in milliseconds */
static const uint32_t mld_timeout_leeway = 500; /* in millseconds */
static bool mld_timeout_run; /* MLD timer is scheduled to run */
static bool mld_fast_timeout_run; /* MLD fast timer is scheduled to run */
static void mld_timeout(thread_call_param_t, thread_call_param_t);
static void mld_sched_timeout(void);
static void mld_sched_fast_timeout(void);
/*
* Normative references: RFC 2710, RFC 3590, RFC 3810.
*/
static struct timeval mld_gsrdelay = {.tv_sec = 10, .tv_usec = 0};
static LIST_HEAD(, mld_ifinfo) mli_head;
static int querier_present_timers_running6;
static int interface_timers_running6;
static int state_change_timers_running6;
static int current_state_timers_running6;
static unsigned int mld_mli_list_genid;
/*
* Subsystem lock macros.
*/
#define MLD_LOCK() \
lck_mtx_lock(&mld_mtx)
#define MLD_LOCK_ASSERT_HELD() \
LCK_MTX_ASSERT(&mld_mtx, LCK_MTX_ASSERT_OWNED)
#define MLD_LOCK_ASSERT_NOTHELD() \
LCK_MTX_ASSERT(&mld_mtx, LCK_MTX_ASSERT_NOTOWNED)
#define MLD_UNLOCK() \
lck_mtx_unlock(&mld_mtx)
#define MLD_ADD_DETACHED_IN6M(_head, _in6m) { \
SLIST_INSERT_HEAD(_head, _in6m, in6m_dtle); \
}
#define MLD_REMOVE_DETACHED_IN6M(_head) { \
struct in6_multi *_in6m, *_inm_tmp; \
SLIST_FOREACH_SAFE(_in6m, _head, in6m_dtle, _inm_tmp) { \
SLIST_REMOVE(_head, _in6m, in6_multi, in6m_dtle); \
IN6M_REMREF(_in6m); \
} \
VERIFY(SLIST_EMPTY(_head)); \
}
static KALLOC_TYPE_DEFINE(mli_zone, struct mld_ifinfo, NET_KT_DEFAULT);
SYSCTL_DECL(_net_inet6); /* Note: Not in any common header. */
SYSCTL_NODE(_net_inet6, OID_AUTO, mld, CTLFLAG_RW | CTLFLAG_LOCKED, 0,
"IPv6 Multicast Listener Discovery");
SYSCTL_PROC(_net_inet6_mld, OID_AUTO, gsrdelay,
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
&mld_gsrdelay.tv_sec, 0, sysctl_mld_gsr, "I",
"Rate limit for MLDv2 Group-and-Source queries in seconds");
SYSCTL_NODE(_net_inet6_mld, OID_AUTO, ifinfo, CTLFLAG_RD | CTLFLAG_LOCKED,
sysctl_mld_ifinfo, "Per-interface MLDv2 state");
static int mld_v1enable = 1;
SYSCTL_INT(_net_inet6_mld, OID_AUTO, v1enable, CTLFLAG_RW | CTLFLAG_LOCKED,
&mld_v1enable, 0, "Enable fallback to MLDv1");
static int mld_v2enable = 1;
SYSCTL_PROC(_net_inet6_mld, OID_AUTO, v2enable,
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
&mld_v2enable, 0, sysctl_mld_v2enable, "I",
"Enable MLDv2 (debug purposes only)");
static int mld_use_allow = 1;
SYSCTL_INT(_net_inet6_mld, OID_AUTO, use_allow, CTLFLAG_RW | CTLFLAG_LOCKED,
&mld_use_allow, 0, "Use ALLOW/BLOCK for RFC 4604 SSM joins/leaves");
#ifdef MLD_DEBUG
int mld_debug = 0;
SYSCTL_INT(_net_inet6_mld, OID_AUTO,
debug, CTLFLAG_RW | CTLFLAG_LOCKED, &mld_debug, 0, "");
#endif
/*
* Packed Router Alert option structure declaration.
*/
struct mld_raopt {
struct ip6_hbh hbh;
struct ip6_opt pad;
struct ip6_opt_router ra;
} __packed;
/*
* Router Alert hop-by-hop option header.
*/
static struct mld_raopt mld_ra = {
.hbh = { .ip6h_nxt = 0, .ip6h_len = 0 },
.pad = { .ip6o_type = IP6OPT_PADN, .ip6o_len = 0 },
.ra = {
.ip6or_type = (u_int8_t)IP6OPT_ROUTER_ALERT,
.ip6or_len = (u_int8_t)(IP6OPT_RTALERT_LEN - 2),
.ip6or_value = {((IP6OPT_RTALERT_MLD >> 8) & 0xFF),
(IP6OPT_RTALERT_MLD & 0xFF) }
}
};
static struct ip6_pktopts mld_po;
/* Store MLDv2 record count in the module private scratch space */
#define vt_nrecs pkt_mpriv.__mpriv_u.__mpriv32[0].__mpriv32_u.__val16[0]
static __inline void
mld_save_context(struct mbuf *m, struct ifnet *ifp)
{
m->m_pkthdr.rcvif = ifp;
}
static __inline void
mld_scrub_context(struct mbuf *m)
{
m->m_pkthdr.rcvif = NULL;
}
/*
* Restore context from a queued output chain.
* Return saved ifp.
*/
static __inline struct ifnet *
mld_restore_context(struct mbuf *m)
{
return m->m_pkthdr.rcvif;
}
/*
* Retrieve or set threshold between group-source queries in seconds.
*/
static int
sysctl_mld_gsr SYSCTL_HANDLER_ARGS
{
#pragma unused(arg1, arg2)
int error;
int i;
MLD_LOCK();
i = (int)mld_gsrdelay.tv_sec;
error = sysctl_handle_int(oidp, &i, 0, req);
if (error || !req->newptr) {
goto out_locked;
}
if (i < -1 || i >= 60) {
error = EINVAL;
goto out_locked;
}
mld_gsrdelay.tv_sec = i;
out_locked:
MLD_UNLOCK();
return error;
}
/*
* Expose struct mld_ifinfo to userland, keyed by ifindex.
* For use by ifmcstat(8).
*
*/
static int
sysctl_mld_ifinfo SYSCTL_HANDLER_ARGS
{
#pragma unused(oidp)
int *name;
int error;
u_int namelen;
struct ifnet *ifp;
struct mld_ifinfo *mli;
struct mld_ifinfo_u mli_u;
name = (int *)arg1;
namelen = arg2;
if (req->newptr != USER_ADDR_NULL) {
return EPERM;
}
if (namelen != 1) {
return EINVAL;
}
MLD_LOCK();
if (name[0] <= 0 || name[0] > (u_int)if_index) {
error = ENOENT;
goto out_locked;
}
error = ENOENT;
ifnet_head_lock_shared();
ifp = ifindex2ifnet[name[0]];
ifnet_head_done();
if (ifp == NULL) {
goto out_locked;
}
bzero(&mli_u, sizeof(mli_u));
LIST_FOREACH(mli, &mli_head, mli_link) {
MLI_LOCK(mli);
if (ifp != mli->mli_ifp) {
MLI_UNLOCK(mli);
continue;
}
mli_u.mli_ifindex = mli->mli_ifp->if_index;
mli_u.mli_version = mli->mli_version;
mli_u.mli_v1_timer = mli->mli_v1_timer;
mli_u.mli_v2_timer = mli->mli_v2_timer;
mli_u.mli_flags = mli->mli_flags;
mli_u.mli_rv = mli->mli_rv;
mli_u.mli_qi = mli->mli_qi;
mli_u.mli_qri = mli->mli_qri;
mli_u.mli_uri = mli->mli_uri;
MLI_UNLOCK(mli);
error = SYSCTL_OUT(req, &mli_u, sizeof(mli_u));
break;
}
out_locked:
MLD_UNLOCK();
return error;
}
static int
sysctl_mld_v2enable SYSCTL_HANDLER_ARGS
{
#pragma unused(arg1, arg2)
int error;
int i;
struct mld_ifinfo *mli;
struct mld_tparams mtp = { .qpt = 0, .it = 0, .cst = 0, .sct = 0 };
MLD_LOCK();
i = mld_v2enable;
error = sysctl_handle_int(oidp, &i, 0, req);
if (error || !req->newptr) {
goto out_locked;
}
if (i < 0 || i > 1) {
error = EINVAL;
goto out_locked;
}
mld_v2enable = i;
/*
* If we enabled v2, the state transition will take care of upgrading
* the MLD version back to v2. Otherwise, we have to explicitly
* downgrade. Note that this functionality is to be used for debugging.
*/
if (mld_v2enable == 1) {
goto out_locked;
}
LIST_FOREACH(mli, &mli_head, mli_link) {
MLI_LOCK(mli);
if (mld_set_version(mli, MLD_VERSION_1) > 0) {
mtp.qpt = 1;
}
MLI_UNLOCK(mli);
}
out_locked:
MLD_UNLOCK();
mld_set_timeout(&mtp);
return error;
}
/*
* Dispatch an entire queue of pending packet chains.
*
* Must not be called with in6m_lock held.
* XXX This routine unlocks MLD global lock and also mli locks.
* Make sure that the calling routine takes reference on the mli
* before calling this routine.
* Also if we are traversing mli_head, remember to check for
* mli list generation count and restart the loop if generation count
* has changed.
*/
static void
mld_dispatch_queue_locked(struct mld_ifinfo *mli, struct ifqueue *ifq, int limit)
{
struct mbuf *m;
MLD_LOCK_ASSERT_HELD();
if (mli != NULL) {
MLI_LOCK_ASSERT_HELD(mli);
}
for (;;) {
IF_DEQUEUE(ifq, m);
if (m == NULL) {
break;
}
MLD_PRINTF(("%s: dispatch 0x%llx from 0x%llx\n", __func__,
(uint64_t)VM_KERNEL_ADDRPERM(ifq),
(uint64_t)VM_KERNEL_ADDRPERM(m)));
if (mli != NULL) {
MLI_UNLOCK(mli);
}
MLD_UNLOCK();
mld_dispatch_packet(m);
MLD_LOCK();
if (mli != NULL) {
MLI_LOCK(mli);
}
if (--limit == 0) {
break;
}
}
if (mli != NULL) {
MLI_LOCK_ASSERT_HELD(mli);
}
}
/*
* Filter outgoing MLD report state by group.
*
* Reports are ALWAYS suppressed for ALL-HOSTS (ff02::1)
* and node-local addresses. However, kernel and socket consumers
* always embed the KAME scope ID in the address provided, so strip it
* when performing comparison.
* Note: This is not the same as the *multicast* scope.
*
* Return zero if the given group is one for which MLD reports
* should be suppressed, or non-zero if reports should be issued.
*/
static __inline__ int
mld_is_addr_reported(const struct in6_addr *addr)
{
VERIFY(IN6_IS_ADDR_MULTICAST(addr));
if (IPV6_ADDR_MC_SCOPE(addr) == IPV6_ADDR_SCOPE_NODELOCAL) {
return 0;
}
if (IPV6_ADDR_MC_SCOPE(addr) == IPV6_ADDR_SCOPE_LINKLOCAL && !IN6_IS_ADDR_UNICAST_BASED_MULTICAST(addr)) {
struct in6_addr tmp = *addr;
in6_clearscope(&tmp);
if (IN6_ARE_ADDR_EQUAL(&tmp, &in6addr_linklocal_allnodes)) {
return 0;
}
}
return 1;
}
/*
* Attach MLD when PF_INET6 is attached to an interface.
*/
struct mld_ifinfo *
mld_domifattach(struct ifnet *ifp, zalloc_flags_t how)
{
struct mld_ifinfo *mli;
os_log_debug(OS_LOG_DEFAULT, "%s: called for ifp %s\n", __func__,
if_name(ifp));
mli = mli_alloc(how);
if (mli == NULL) {
return NULL;
}
MLD_LOCK();
MLI_LOCK(mli);
mli_initvar(mli, ifp, 0);
mli->mli_debug |= IFD_ATTACHED;
MLI_ADDREF_LOCKED(mli); /* hold a reference for mli_head */
MLI_ADDREF_LOCKED(mli); /* hold a reference for caller */
MLI_UNLOCK(mli);
ifnet_lock_shared(ifp);
mld6_initsilent(ifp, mli);
ifnet_lock_done(ifp);
LIST_INSERT_HEAD(&mli_head, mli, mli_link);
mld_mli_list_genid++;
MLD_UNLOCK();
os_log_info(OS_LOG_DEFAULT, "%s: allocated mld_ifinfo for ifp %s\n",
__func__, if_name(ifp));
return mli;
}
/*
* Attach MLD when PF_INET6 is reattached to an interface. Caller is
* expected to have an outstanding reference to the mli.
*/
void
mld_domifreattach(struct mld_ifinfo *mli)
{
struct ifnet *ifp;
MLD_LOCK();
MLI_LOCK(mli);
VERIFY(!(mli->mli_debug & IFD_ATTACHED));
ifp = mli->mli_ifp;
VERIFY(ifp != NULL);
mli_initvar(mli, ifp, 1);
mli->mli_debug |= IFD_ATTACHED;
MLI_ADDREF_LOCKED(mli); /* hold a reference for mli_head */
MLI_UNLOCK(mli);
ifnet_lock_shared(ifp);
mld6_initsilent(ifp, mli);
ifnet_lock_done(ifp);
LIST_INSERT_HEAD(&mli_head, mli, mli_link);
mld_mli_list_genid++;
MLD_UNLOCK();
os_log_info(OS_LOG_DEFAULT, "%s: reattached mld_ifinfo for ifp %s\n",
__func__, if_name(ifp));
}
/*
* Hook for domifdetach.
*/
void
mld_domifdetach(struct ifnet *ifp)
{
SLIST_HEAD(, in6_multi) in6m_dthead;
SLIST_INIT(&in6m_dthead);
os_log_info(OS_LOG_DEFAULT, "%s: called for ifp %s\n", __func__,
if_name(ifp));
MLD_LOCK();
mli_delete(ifp, (struct mld_in6m_relhead *)&in6m_dthead);
MLD_UNLOCK();
/* Now that we're dropped all locks, release detached records */
MLD_REMOVE_DETACHED_IN6M(&in6m_dthead);
}
/*
* Called at interface detach time. Note that we only flush all deferred
* responses and record releases; all remaining inm records and their source
* entries related to this interface are left intact, in order to handle
* the reattach case.
*/
static void
mli_delete(const struct ifnet *ifp, struct mld_in6m_relhead *in6m_dthead)
{
struct mld_ifinfo *mli, *tmli;
MLD_LOCK_ASSERT_HELD();
LIST_FOREACH_SAFE(mli, &mli_head, mli_link, tmli) {
MLI_LOCK(mli);
if (mli->mli_ifp == ifp) {
/*
* Free deferred General Query responses.
*/
IF_DRAIN(&mli->mli_gq);
IF_DRAIN(&mli->mli_v1q);
mld_flush_relq(mli, in6m_dthead);
mli->mli_debug &= ~IFD_ATTACHED;
MLI_UNLOCK(mli);
LIST_REMOVE(mli, mli_link);
MLI_REMREF(mli); /* release mli_head reference */
mld_mli_list_genid++;
return;
}
MLI_UNLOCK(mli);
}
panic("%s: mld_ifinfo not found for ifp %p(%s)", __func__,
ifp, ifp->if_xname);
}
__private_extern__ void
mld6_initsilent(struct ifnet *ifp, struct mld_ifinfo *mli)
{
ifnet_lock_assert(ifp, IFNET_LCK_ASSERT_OWNED);
MLI_LOCK_ASSERT_NOTHELD(mli);
MLI_LOCK(mli);
if (!(ifp->if_flags & IFF_MULTICAST) &&
(ifp->if_eflags & (IFEF_IPV6_ND6ALT | IFEF_LOCALNET_PRIVATE))) {
mli->mli_flags |= MLIF_SILENT;
} else {
mli->mli_flags &= ~MLIF_SILENT;
}
MLI_UNLOCK(mli);
}
static void
mli_initvar(struct mld_ifinfo *mli, struct ifnet *ifp, int reattach)
{
MLI_LOCK_ASSERT_HELD(mli);
mli->mli_ifp = ifp;
if (mld_v2enable) {
mli->mli_version = MLD_VERSION_2;
} else {
mli->mli_version = MLD_VERSION_1;
}
mli->mli_flags = 0;
mli->mli_rv = MLD_RV_INIT;
mli->mli_qi = MLD_QI_INIT;
mli->mli_qri = MLD_QRI_INIT;
mli->mli_uri = MLD_URI_INIT;
if (mld_use_allow) {
mli->mli_flags |= MLIF_USEALLOW;
}
if (!reattach) {
SLIST_INIT(&mli->mli_relinmhead);
}
/*
* Responses to general queries are subject to bounds.
*/
mli->mli_gq.ifq_maxlen = MLD_MAX_RESPONSE_PACKETS;
mli->mli_v1q.ifq_maxlen = MLD_MAX_RESPONSE_PACKETS;
}
static struct mld_ifinfo *
mli_alloc(zalloc_flags_t how)
{
struct mld_ifinfo *mli = zalloc_flags(mli_zone, how | Z_ZERO);
if (mli != NULL) {
lck_mtx_init(&mli->mli_lock, &mld_mtx_grp, &mld_mtx_attr);
mli->mli_debug |= IFD_ALLOC;
}
return mli;
}
static void
mli_free(struct mld_ifinfo *mli)
{
MLI_LOCK(mli);
if (mli->mli_debug & IFD_ATTACHED) {
panic("%s: attached mli=%p is being freed", __func__, mli);
/* NOTREACHED */
} else if (mli->mli_ifp != NULL) {
panic("%s: ifp not NULL for mli=%p", __func__, mli);
/* NOTREACHED */
} else if (!(mli->mli_debug & IFD_ALLOC)) {
panic("%s: mli %p cannot be freed", __func__, mli);
/* NOTREACHED */
} else if (mli->mli_refcnt != 0) {
panic("%s: non-zero refcnt mli=%p", __func__, mli);
/* NOTREACHED */
}
mli->mli_debug &= ~IFD_ALLOC;
MLI_UNLOCK(mli);
lck_mtx_destroy(&mli->mli_lock, &mld_mtx_grp);
zfree(mli_zone, mli);
}
void
mli_addref(struct mld_ifinfo *mli, int locked)
{
if (!locked) {
MLI_LOCK_SPIN(mli);
} else {
MLI_LOCK_ASSERT_HELD(mli);
}
if (++mli->mli_refcnt == 0) {
panic("%s: mli=%p wraparound refcnt", __func__, mli);
/* NOTREACHED */
}
if (!locked) {
MLI_UNLOCK(mli);
}
}
void
mli_remref(struct mld_ifinfo *mli)
{
SLIST_HEAD(, in6_multi) in6m_dthead;
struct ifnet *ifp;
MLI_LOCK_SPIN(mli);
if (mli->mli_refcnt == 0) {
panic("%s: mli=%p negative refcnt", __func__, mli);
/* NOTREACHED */
}
--mli->mli_refcnt;
if (mli->mli_refcnt > 0) {
MLI_UNLOCK(mli);
return;
}
ifp = mli->mli_ifp;
mli->mli_ifp = NULL;
IF_DRAIN(&mli->mli_gq);
IF_DRAIN(&mli->mli_v1q);
SLIST_INIT(&in6m_dthead);
mld_flush_relq(mli, (struct mld_in6m_relhead *)&in6m_dthead);
MLI_UNLOCK(mli);
/* Now that we're dropped all locks, release detached records */
MLD_REMOVE_DETACHED_IN6M(&in6m_dthead);
os_log(OS_LOG_DEFAULT, "%s: freeing mld_ifinfo for ifp %s\n",
__func__, if_name(ifp));
mli_free(mli);
}
/*
* Process a received MLDv1 general or address-specific query.
* Assumes that the query header has been pulled up to sizeof(mld_hdr).
*
* NOTE: Can't be fully const correct as we temporarily embed scope ID in
* mld_addr. This is OK as we own the mbuf chain.
*/
static int
mld_v1_input_query(struct ifnet *ifp, const struct ip6_hdr *ip6,
/*const*/ struct mld_hdr *mld)
{
struct mld_ifinfo *mli;
struct in6_multi *inm;
int err = 0, is_general_query;
uint16_t timer;
struct mld_tparams mtp = { .qpt = 0, .it = 0, .cst = 0, .sct = 0 };
MLD_LOCK_ASSERT_NOTHELD();
is_general_query = 0;
if (!mld_v1enable) {
os_log_info(OS_LOG_DEFAULT, "%s: ignore v1 query on ifp %s\n",
__func__, if_name(ifp));
goto done;
}
/*
* RFC3810 Section 6.2: MLD queries must originate from
* a router's link-local address.
*/
if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
os_log_info(OS_LOG_DEFAULT, "%s: ignore v1 query src %s on ifp %s\n",
__func__, ip6_sprintf(&ip6->ip6_src),
if_name(ifp));
goto done;
}
/*
* Do address field validation upfront before we accept
* the query.
*/
if (IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr)) {
/*
* MLDv1 General Query.
* If this was not sent to the all-nodes group, ignore it.
*/
struct in6_addr dst;
dst = ip6->ip6_dst;
in6_clearscope(&dst);
if (!IN6_ARE_ADDR_EQUAL(&dst, &in6addr_linklocal_allnodes)) {
err = EINVAL;
goto done;
}
is_general_query = 1;
} else {
/*
* Embed scope ID of receiving interface in MLD query for
* lookup whilst we don't hold other locks.
*/
(void)in6_setscope(&mld->mld_addr, ifp, NULL);
}
/*
* Switch to MLDv1 host compatibility mode.
*/
mli = MLD_IFINFO(ifp);
VERIFY(mli != NULL);
MLI_LOCK(mli);
mtp.qpt = mld_set_version(mli, MLD_VERSION_1);
MLI_UNLOCK(mli);
timer = ntohs(mld->mld_maxdelay) / MLD_TIMER_SCALE;
if (timer == 0) {
timer = 1;
}
if (is_general_query) {
struct in6_multistep step;
os_log_debug(OS_LOG_DEFAULT, "%s: process v1 general query on ifp %s\n",
__func__, if_name(ifp));
/*
* For each reporting group joined on this
* interface, kick the report timer.
*/
in6_multihead_lock_shared();
IN6_FIRST_MULTI(step, inm);
while (inm != NULL) {
IN6M_LOCK(inm);
if (inm->in6m_ifp == ifp) {
mtp.cst += mld_v1_update_group(inm, timer);
}
IN6M_UNLOCK(inm);
IN6_NEXT_MULTI(step, inm);
}
in6_multihead_lock_done();
} else {
/*
* MLDv1 Group-Specific Query.
* If this is a group-specific MLDv1 query, we need only
* look up the single group to process it.
*/
in6_multihead_lock_shared();
IN6_LOOKUP_MULTI(&mld->mld_addr, ifp, inm);
in6_multihead_lock_done();
if (inm != NULL) {
IN6M_LOCK(inm);
os_log_debug(OS_LOG_DEFAULT, "%s: process v1 query %s on "
"ifp %s\n", __func__,
ip6_sprintf(&mld->mld_addr),
if_name(ifp));
mtp.cst = mld_v1_update_group(inm, timer);
IN6M_UNLOCK(inm);
IN6M_REMREF(inm); /* from IN6_LOOKUP_MULTI */
}
/* XXX Clear embedded scope ID as userland won't expect it. */
in6_clearscope(&mld->mld_addr);
}
done:
mld_set_timeout(&mtp);
return err;
}
/*
* Update the report timer on a group in response to an MLDv1 query.
*
* If we are becoming the reporting member for this group, start the timer.
* If we already are the reporting member for this group, and timer is
* below the threshold, reset it.
*
* We may be updating the group for the first time since we switched
* to MLDv2. If we are, then we must clear any recorded source lists,
* and transition to REPORTING state; the group timer is overloaded
* for group and group-source query responses.
*
* Unlike MLDv2, the delay per group should be jittered
* to avoid bursts of MLDv1 reports.
*/
static uint32_t
mld_v1_update_group(struct in6_multi *inm, const int timer)
{
IN6M_LOCK_ASSERT_HELD(inm);
MLD_PRINTF(("%s: %s/%s timer=%d\n", __func__,
ip6_sprintf(&inm->in6m_addr),
if_name(inm->in6m_ifp), timer));
switch (inm->in6m_state) {
case MLD_NOT_MEMBER:
case MLD_SILENT_MEMBER:
break;
case MLD_REPORTING_MEMBER:
if (inm->in6m_timer != 0 &&
inm->in6m_timer <= timer) {
MLD_PRINTF(("%s: REPORTING and timer running, "
"skipping.\n", __func__));
break;
}
OS_FALLTHROUGH;
case MLD_SG_QUERY_PENDING_MEMBER:
case MLD_G_QUERY_PENDING_MEMBER:
case MLD_IDLE_MEMBER:
case MLD_LAZY_MEMBER:
case MLD_AWAKENING_MEMBER:
MLD_PRINTF(("%s: ->REPORTING\n", __func__));
inm->in6m_state = MLD_REPORTING_MEMBER;
inm->in6m_timer = MLD_RANDOM_DELAY(timer);
break;
case MLD_SLEEPING_MEMBER:
MLD_PRINTF(("%s: ->AWAKENING\n", __func__));
inm->in6m_state = MLD_AWAKENING_MEMBER;
break;
case MLD_LEAVING_MEMBER:
break;
}
return inm->in6m_timer;
}
/*
* Process a received MLDv2 general, group-specific or
* group-and-source-specific query.
*
* Assumes that the query header has been pulled up to sizeof(mldv2_query).
*
* Return 0 if successful, otherwise an appropriate error code is returned.
*/
static int
mld_v2_input_query(struct ifnet *ifp, const struct ip6_hdr *ip6,
struct mbuf *m, const int off, const int icmp6len)
{
struct mld_ifinfo *mli;
struct mldv2_query *mld;
struct in6_multi *inm;
uint32_t maxdelay, nsrc, qqi, timer;
int err = 0, is_general_query;
uint8_t qrv;
struct mld_tparams mtp = { .qpt = 0, .it = 0, .cst = 0, .sct = 0 };
MLD_LOCK_ASSERT_NOTHELD();
is_general_query = 0;
if (!mld_v2enable) {
os_log_info(OS_LOG_DEFAULT, "%s: ignore v2 query on ifp %s\n",
__func__, if_name(ifp));
goto done;
}
/*
* RFC3810 Section 6.2: MLD queries must originate from
* a router's link-local address.
*/
if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
os_log_info(OS_LOG_DEFAULT,
"%s: ignore v1 query src %s on ifp %s\n",
__func__, ip6_sprintf(&ip6->ip6_src),
if_name(ifp));
goto done;
}
os_log_debug(OS_LOG_DEFAULT,
"%s: input v2 query on ifp %s\n", __func__,
if_name(ifp));
mld = (struct mldv2_query *)(mtod(m, uint8_t *) + off);
maxdelay = ntohs(mld->mld_maxdelay); /* in 1/10ths of a second */
if (maxdelay > SHRT_MAX) {
maxdelay = (MLD_MRC_MANT((uint16_t)maxdelay) | 0x1000) <<
(MLD_MRC_EXP((uint16_t)maxdelay) + 3);
}
timer = maxdelay / MLD_TIMER_SCALE;
if (timer == 0) {
timer = 1;
}
qrv = MLD_QRV(mld->mld_misc);
if (qrv < 2) {
MLD_PRINTF(("%s: clamping qrv %d to %d\n", __func__,
qrv, MLD_RV_INIT));
qrv = MLD_RV_INIT;
}
qqi = mld->mld_qqi;
if (qqi >= 128) {
qqi = MLD_QQIC_MANT(mld->mld_qqi) <<
(MLD_QQIC_EXP(mld->mld_qqi) + 3);
}
nsrc = ntohs(mld->mld_numsrc);
if (nsrc > MLD_MAX_GS_SOURCES) {
err = EMSGSIZE;
goto done;
}
if (icmp6len < sizeof(struct mldv2_query) +
(nsrc * sizeof(struct in6_addr))) {
err = EMSGSIZE;
goto done;
}
/*
* Do further input validation upfront to avoid resetting timers
* should we need to discard this query.
*/
if (IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr)) {
/*
* A general query with a source list has undefined
* behaviour; discard it.
*/
if (nsrc > 0) {
err = EINVAL;
goto done;
}
is_general_query = 1;
} else {
/*
* Embed scope ID of receiving interface in MLD query for
* lookup whilst we don't hold other locks (due to KAME
* locking lameness). We own this mbuf chain just now.
*/
(void)in6_setscope(&mld->mld_addr, ifp, NULL);
}
mli = MLD_IFINFO(ifp);
VERIFY(mli != NULL);
MLI_LOCK(mli);
/*
* Discard the v2 query if we're in Compatibility Mode.
* The RFC is pretty clear that hosts need to stay in MLDv1 mode
* until the Old Version Querier Present timer expires.
*/
if (mli->mli_version != MLD_VERSION_2) {
MLI_UNLOCK(mli);
goto done;
}
mtp.qpt = mld_set_version(mli, MLD_VERSION_2);
mli->mli_rv = qrv;
mli->mli_qi = qqi;
mli->mli_qri = MAX(timer, MLD_QRI_MIN);
MLD_PRINTF(("%s: qrv %d qi %d qri %d\n", __func__, mli->mli_rv,
mli->mli_qi, mli->mli_qri));
if (is_general_query) {
/*
* MLDv2 General Query.
*
* Schedule a current-state report on this ifp for
* all groups, possibly containing source lists.
*
* If there is a pending General Query response
* scheduled earlier than the selected delay, do
* not schedule any other reports.
* Otherwise, reset the interface timer.
*/
os_log_debug(OS_LOG_DEFAULT, "%s: process v2 general query on ifp %s\n",
__func__, if_name(ifp));
if (mli->mli_v2_timer == 0 || mli->mli_v2_timer >= timer) {
mtp.it = mli->mli_v2_timer = MLD_RANDOM_DELAY(timer);
}
MLI_UNLOCK(mli);
} else {
MLI_UNLOCK(mli);
/*
* MLDv2 Group-specific or Group-and-source-specific Query.
*
* Group-source-specific queries are throttled on
* a per-group basis to defeat denial-of-service attempts.
* Queries for groups we are not a member of on this
* link are simply ignored.
*/
in6_multihead_lock_shared();
IN6_LOOKUP_MULTI(&mld->mld_addr, ifp, inm);
in6_multihead_lock_done();
if (inm == NULL) {
goto done;
}
IN6M_LOCK(inm);
if (nsrc > 0) {
if (!ratecheck(&inm->in6m_lastgsrtv,
&mld_gsrdelay)) {
os_log_info(OS_LOG_DEFAULT, "%s: GS query throttled\n",
__func__);
IN6M_UNLOCK(inm);
IN6M_REMREF(inm); /* from IN6_LOOKUP_MULTI */
goto done;
}
}
os_log_debug(OS_LOG_DEFAULT, "%s: process v2 group query on ifp %s\n",
__func__, if_name(ifp));
/*
* If there is a pending General Query response
* scheduled sooner than the selected delay, no
* further report need be scheduled.
* Otherwise, prepare to respond to the
* group-specific or group-and-source query.
*/
MLI_LOCK(mli);
mtp.it = mli->mli_v2_timer;
MLI_UNLOCK(mli);
if (mtp.it == 0 || mtp.it >= timer) {
(void) mld_v2_process_group_query(inm, timer, m, off);
mtp.cst = inm->in6m_timer;
}
IN6M_UNLOCK(inm);
IN6M_REMREF(inm); /* from IN6_LOOKUP_MULTI */
/* XXX Clear embedded scope ID as userland won't expect it. */
in6_clearscope(&mld->mld_addr);
}
done:
if (mtp.it > 0) {
os_log_debug(OS_LOG_DEFAULT, "%s: v2 general query response scheduled in "
"T+%d seconds on ifp %s\n", __func__, mtp.it,
if_name(ifp));
}
mld_set_timeout(&mtp);
return err;
}
/*
* Process a recieved MLDv2 group-specific or group-and-source-specific
* query.
* Return <0 if any error occured. Currently this is ignored.
*/
static int
mld_v2_process_group_query(struct in6_multi *inm, int timer, struct mbuf *m0,
const int off)
{
struct mldv2_query *mld;
int retval;
uint16_t nsrc;
IN6M_LOCK_ASSERT_HELD(inm);
retval = 0;
mld = (struct mldv2_query *)(mtod(m0, uint8_t *) + off);
switch (inm->in6m_state) {
case MLD_NOT_MEMBER:
case MLD_SILENT_MEMBER:
case MLD_SLEEPING_MEMBER:
case MLD_LAZY_MEMBER:
case MLD_AWAKENING_MEMBER:
case MLD_IDLE_MEMBER:
case MLD_LEAVING_MEMBER:
return retval;
case MLD_REPORTING_MEMBER:
case MLD_G_QUERY_PENDING_MEMBER:
case MLD_SG_QUERY_PENDING_MEMBER:
break;
}
nsrc = ntohs(mld->mld_numsrc);
/*
* Deal with group-specific queries upfront.
* If any group query is already pending, purge any recorded
* source-list state if it exists, and schedule a query response
* for this group-specific query.
*/
if (nsrc == 0) {
if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER ||
inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER) {
in6m_clear_recorded(inm);
timer = min(inm->in6m_timer, timer);
}
inm->in6m_state = MLD_G_QUERY_PENDING_MEMBER;
inm->in6m_timer = MLD_RANDOM_DELAY(timer);
return retval;
}
/*
* Deal with the case where a group-and-source-specific query has
* been received but a group-specific query is already pending.
*/
if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER) {
timer = min(inm->in6m_timer, timer);
inm->in6m_timer = MLD_RANDOM_DELAY(timer);
return retval;
}
/*
* Finally, deal with the case where a group-and-source-specific
* query has been received, where a response to a previous g-s-r
* query exists, or none exists.
* In this case, we need to parse the source-list which the Querier
* has provided us with and check if we have any source list filter
* entries at T1 for these sources. If we do not, there is no need
* schedule a report and the query may be dropped.
* If we do, we must record them and schedule a current-state
* report for those sources.
*/
if (inm->in6m_nsrc > 0) {
struct mbuf *m;
struct in6_addr addr;
int i, nrecorded;
int soff;
m = m0;
soff = off + sizeof(struct mldv2_query);
nrecorded = 0;
for (i = 0; i < nsrc; i++) {
m_copydata(m, soff, sizeof(addr), &addr);
retval = in6m_record_source(inm, &addr);
if (retval < 0) {
break;
}
nrecorded += retval;
soff += sizeof(struct in6_addr);
while (m && (soff >= m->m_len)) {
soff -= m->m_len;
m = m->m_next;
}
/* should not be possible: */
if (m == NULL) {
break;
}
}
if (nrecorded > 0) {
MLD_PRINTF(("%s: schedule response to SG query\n",
__func__));
inm->in6m_state = MLD_SG_QUERY_PENDING_MEMBER;
inm->in6m_timer = MLD_RANDOM_DELAY(timer);
}
}
return retval;
}
/*
* Process a received MLDv1 host membership report.
* Assumes mld points to mld_hdr in pulled up mbuf chain.
*
* NOTE: Can't be fully const correct as we temporarily embed scope ID in
* mld_addr. This is OK as we own the mbuf chain.
*/
static int
mld_v1_input_report(struct ifnet *ifp, struct mbuf *m,
const struct ip6_hdr *ip6, /*const*/ struct mld_hdr *mld)
{
struct in6_addr src, dst;
struct in6_ifaddr *ia;
struct in6_multi *inm;
if (!mld_v1enable) {
os_log_info(OS_LOG_DEFAULT, "%s: ignore v1 report on ifp %s\n",
__func__, if_name(ifp));
return 0;
}
if ((ifp->if_flags & IFF_LOOPBACK) ||
(m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
return 0;
}
/*
* MLDv1 reports must originate from a host's link-local address,
* or the unspecified address (when booting).
*/
src = ip6->ip6_src;
in6_clearscope(&src);
if (!IN6_IS_SCOPE_LINKLOCAL(&src) && !IN6_IS_ADDR_UNSPECIFIED(&src)) {
os_log_info(OS_LOG_DEFAULT, "%s: ignore v1 query src %s on ifp %s\n",
__func__, ip6_sprintf(&ip6->ip6_src),
if_name(ifp));
return EINVAL;
}
/*
* RFC2710 Section 4: MLDv1 reports must pertain to a multicast
* group, and must be directed to the group itself.
*/
dst = ip6->ip6_dst;
in6_clearscope(&dst);
if (!IN6_IS_ADDR_MULTICAST(&mld->mld_addr) ||
!IN6_ARE_ADDR_EQUAL(&mld->mld_addr, &dst)) {
os_log_info(OS_LOG_DEFAULT, "%s: ignore v1 query dst %s on ifp %s\n",
__func__, ip6_sprintf(&ip6->ip6_dst),
if_name(ifp));
return EINVAL;
}
/*
* Make sure we don't hear our own membership report, as fast
* leave requires knowing that we are the only member of a
* group. Assume we used the link-local address if available,
* otherwise look for ::.
*
* XXX Note that scope ID comparison is needed for the address
* returned by in6ifa_ifpforlinklocal(), but SHOULD NOT be
* performed for the on-wire address.
*/
ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY | IN6_IFF_ANYCAST);
if (ia != NULL) {
IFA_LOCK(&ia->ia_ifa);
if ((IN6_ARE_ADDR_EQUAL(&ip6->ip6_src, IA6_IN6(ia)))) {
IFA_UNLOCK(&ia->ia_ifa);
ifa_remref(&ia->ia_ifa);
return 0;
}
IFA_UNLOCK(&ia->ia_ifa);
ifa_remref(&ia->ia_ifa);
} else if (IN6_IS_ADDR_UNSPECIFIED(&src)) {
return 0;
}
os_log_debug(OS_LOG_DEFAULT, "%s: process v1 report %s on ifp %s\n",
__func__, ip6_sprintf(&mld->mld_addr),
if_name(ifp));
/*
* Embed scope ID of receiving interface in MLD query for lookup
* whilst we don't hold other locks (due to KAME locking lameness).
*/
if (!IN6_IS_ADDR_UNSPECIFIED(&mld->mld_addr)) {
(void)in6_setscope(&mld->mld_addr, ifp, NULL);
}
/*
* MLDv1 report suppression.
* If we are a member of this group, and our membership should be
* reported, and our group timer is pending or about to be reset,
* stop our group timer by transitioning to the 'lazy' state.
*/
in6_multihead_lock_shared();
IN6_LOOKUP_MULTI(&mld->mld_addr, ifp, inm);
in6_multihead_lock_done();
if (inm != NULL) {
struct mld_ifinfo *mli;
IN6M_LOCK(inm);
mli = inm->in6m_mli;
VERIFY(mli != NULL);
MLI_LOCK(mli);
/*
* If we are in MLDv2 host mode, do not allow the
* other host's MLDv1 report to suppress our reports.
*/
if (mli->mli_version == MLD_VERSION_2) {
MLI_UNLOCK(mli);
IN6M_UNLOCK(inm);
IN6M_REMREF(inm); /* from IN6_LOOKUP_MULTI */
goto out;
}
MLI_UNLOCK(mli);
inm->in6m_timer = 0;
switch (inm->in6m_state) {
case MLD_NOT_MEMBER:
case MLD_SILENT_MEMBER:
case MLD_SLEEPING_MEMBER:
break;
case MLD_REPORTING_MEMBER:
case MLD_IDLE_MEMBER:
case MLD_AWAKENING_MEMBER:
MLD_PRINTF(("%s: report suppressed for %s on "
"ifp 0x%llx(%s)\n", __func__,
ip6_sprintf(&mld->mld_addr),
(uint64_t)VM_KERNEL_ADDRPERM(ifp), if_name(ifp)));
OS_FALLTHROUGH;
case MLD_LAZY_MEMBER:
inm->in6m_state = MLD_LAZY_MEMBER;
break;
case MLD_G_QUERY_PENDING_MEMBER:
case MLD_SG_QUERY_PENDING_MEMBER:
case MLD_LEAVING_MEMBER:
break;
}
IN6M_UNLOCK(inm);
IN6M_REMREF(inm); /* from IN6_LOOKUP_MULTI */
}
out:
/* XXX Clear embedded scope ID as userland won't expect it. */
in6_clearscope(&mld->mld_addr);
return 0;
}
/*
* MLD input path.
*
* Assume query messages which fit in a single ICMPv6 message header
* have been pulled up.
* Assume that userland will want to see the message, even if it
* otherwise fails kernel input validation; do not free it.
* Pullup may however free the mbuf chain m if it fails.
*
* Return IPPROTO_DONE if we freed m. Otherwise, return 0.
*/
int
mld_input(struct mbuf *m, int off, int icmp6len)
{
struct ifnet *ifp = NULL;
struct ip6_hdr *ip6 = NULL;
struct mld_hdr *mld = NULL;
int mldlen = 0;
MLD_PRINTF(("%s: called w/mbuf (0x%llx,%d)\n", __func__,
(uint64_t)VM_KERNEL_ADDRPERM(m), off));
ifp = m->m_pkthdr.rcvif;
/* Pullup to appropriate size. */
mld = (struct mld_hdr *)(mtod(m, uint8_t *) + off);
if (mld->mld_type == MLD_LISTENER_QUERY &&
icmp6len >= sizeof(struct mldv2_query)) {
mldlen = sizeof(struct mldv2_query);
} else {
mldlen = sizeof(struct mld_hdr);
}
// check if mldv2_query/mld_hdr fits in the first mbuf
IP6_EXTHDR_CHECK(m, off, mldlen, return IPPROTO_DONE);
IP6_EXTHDR_GET(mld, struct mld_hdr *, m, off, mldlen);
if (mld == NULL) {
icmp6stat.icp6s_badlen++;
return IPPROTO_DONE;
}
ip6 = mtod(m, struct ip6_hdr *);
/*
* Userland needs to see all of this traffic for implementing
* the endpoint discovery portion of multicast routing.
*/
switch (mld->mld_type) {
case MLD_LISTENER_QUERY:
icmp6_ifstat_inc(ifp, ifs6_in_mldquery);
if (icmp6len == sizeof(struct mld_hdr)) {
if (mld_v1_input_query(ifp, ip6, mld) != 0) {
return 0;
}
} else if (icmp6len >= sizeof(struct mldv2_query)) {
if (mld_v2_input_query(ifp, ip6, m, off,
icmp6len) != 0) {
return 0;
}
}
break;
case MLD_LISTENER_REPORT:
icmp6_ifstat_inc(ifp, ifs6_in_mldreport);
if (mld_v1_input_report(ifp, m, ip6, mld) != 0) {
return 0;
}
break;
case MLDV2_LISTENER_REPORT:
icmp6_ifstat_inc(ifp, ifs6_in_mldreport);
break;
case MLD_LISTENER_DONE:
icmp6_ifstat_inc(ifp, ifs6_in_mlddone);
break;
default:
break;
}
return 0;
}
/*
* Schedule MLD timer based on various parameters; caller must ensure that
* lock ordering is maintained as this routine acquires MLD global lock.
*/
void
mld_set_timeout(struct mld_tparams *mtp)
{
MLD_LOCK_ASSERT_NOTHELD();
VERIFY(mtp != NULL);
if (mtp->qpt != 0 || mtp->it != 0 || mtp->cst != 0 || mtp->sct != 0) {
MLD_LOCK();
if (mtp->qpt != 0) {
querier_present_timers_running6 = 1;
}
if (mtp->it != 0) {
interface_timers_running6 = 1;
}
if (mtp->cst != 0) {
current_state_timers_running6 = 1;
}
if (mtp->sct != 0) {
state_change_timers_running6 = 1;
}
if (mtp->fast) {
mld_sched_fast_timeout();
} else {
mld_sched_timeout();
}
MLD_UNLOCK();
}
}
void
mld_set_fast_timeout(struct mld_tparams *mtp)
{
VERIFY(mtp != NULL);
mtp->fast = true;
mld_set_timeout(mtp);
}
/*
* MLD6 timer handler (per 1 second).
*/
static void
mld_timeout(thread_call_param_t arg0, thread_call_param_t arg1 __unused)
{
struct ifqueue scq; /* State-change packets */
struct ifqueue qrq; /* Query response packets */
struct ifnet *ifp;
struct mld_ifinfo *mli;
struct in6_multi *inm;
int uri_sec = 0;
unsigned int genid = mld_mli_list_genid;
bool fast = arg0 != NULL;
SLIST_HEAD(, in6_multi) in6m_dthead;
SLIST_INIT(&in6m_dthead);
/*
* Update coarse-grained networking timestamp (in sec.); the idea
* is to piggy-back on the timeout callout to update the counter
* returnable via net_uptime().
*/
net_update_uptime();
MLD_LOCK();
MLD_PRINTF(("%s: qpt %d, it %d, cst %d, sct %d, fast %d\n", __func__,
querier_present_timers_running6, interface_timers_running6,
current_state_timers_running6, state_change_timers_running6, fast));
if (fast) {
/*
* When running the fast timer, skip processing
* of "querier present" timers since they are
* based on 1-second intervals.
*/
goto skip_query_timers;
}
/*
* MLDv1 querier present timer processing.
*/
if (querier_present_timers_running6) {
querier_present_timers_running6 = 0;
LIST_FOREACH(mli, &mli_head, mli_link) {
MLI_LOCK(mli);
mld_v1_process_querier_timers(mli);
if (mli->mli_v1_timer > 0) {
querier_present_timers_running6 = 1;
}
MLI_UNLOCK(mli);
}
}
/*
* MLDv2 General Query response timer processing.
*/
if (interface_timers_running6) {
MLD_PRINTF(("%s: interface timers running\n", __func__));
interface_timers_running6 = 0;
mli = LIST_FIRST(&mli_head);
while (mli != NULL) {
if (mli->mli_flags & MLIF_PROCESSED) {
mli = LIST_NEXT(mli, mli_link);
continue;
}
MLI_LOCK(mli);
if (mli->mli_version != MLD_VERSION_2) {
MLI_UNLOCK(mli);
mli = LIST_NEXT(mli, mli_link);
continue;
}
/*
* XXX The logic below ends up calling
* mld_dispatch_packet which can unlock mli
* and the global MLD lock.
* Therefore grab a reference on MLI and also
* check for generation count to see if we should
* iterate the list again.
*/
MLI_ADDREF_LOCKED(mli);
if (mli->mli_v2_timer == 0) {
/* Do nothing. */
} else if (--mli->mli_v2_timer == 0) {
if (mld_v2_dispatch_general_query(mli) > 0) {
interface_timers_running6 = 1;
}
} else {
interface_timers_running6 = 1;
}
mli->mli_flags |= MLIF_PROCESSED;
MLI_UNLOCK(mli);
MLI_REMREF(mli);
if (genid != mld_mli_list_genid) {
MLD_PRINTF(("%s: MLD information list changed "
"in the middle of iteration! Restart iteration.\n",
__func__));
mli = LIST_FIRST(&mli_head);
genid = mld_mli_list_genid;
} else {
mli = LIST_NEXT(mli, mli_link);
}
}
LIST_FOREACH(mli, &mli_head, mli_link)
mli->mli_flags &= ~MLIF_PROCESSED;
}
skip_query_timers:
if (!current_state_timers_running6 &&
!state_change_timers_running6) {
goto out_locked;
}
current_state_timers_running6 = 0;
state_change_timers_running6 = 0;
MLD_PRINTF(("%s: state change timers running\n", __func__));
memset(&qrq, 0, sizeof(struct ifqueue));
qrq.ifq_maxlen = MLD_MAX_G_GS_PACKETS;
memset(&scq, 0, sizeof(struct ifqueue));
scq.ifq_maxlen = MLD_MAX_STATE_CHANGE_PACKETS;
/*
* MLD host report and state-change timer processing.
* Note: Processing a v2 group timer may remove a node.
*/
mli = LIST_FIRST(&mli_head);
while (mli != NULL) {
struct in6_multistep step;
if (mli->mli_flags & MLIF_PROCESSED) {
mli = LIST_NEXT(mli, mli_link);
continue;
}
MLI_LOCK(mli);
ifp = mli->mli_ifp;
uri_sec = MLD_RANDOM_DELAY(mli->mli_uri);
MLI_UNLOCK(mli);
in6_multihead_lock_shared();
IN6_FIRST_MULTI(step, inm);
while (inm != NULL) {
IN6M_LOCK(inm);
if (inm->in6m_ifp != ifp) {
goto next;
}
MLI_LOCK(mli);
switch (mli->mli_version) {
case MLD_VERSION_1:
mld_v1_process_group_timer(inm,
mli->mli_version);
break;
case MLD_VERSION_2:
mld_v2_process_group_timers(mli, &qrq,
&scq, inm, uri_sec);
break;
}
MLI_UNLOCK(mli);
next:
IN6M_UNLOCK(inm);
IN6_NEXT_MULTI(step, inm);
}
in6_multihead_lock_done();
/*
* XXX The logic below ends up calling
* mld_dispatch_packet which can unlock mli
* and the global MLD lock.
* Therefore grab a reference on MLI and also
* check for generation count to see if we should
* iterate the list again.
*/
MLI_LOCK(mli);
MLI_ADDREF_LOCKED(mli);
if (mli->mli_version == MLD_VERSION_1) {
mld_dispatch_queue_locked(mli, &mli->mli_v1q, 0);
} else if (mli->mli_version == MLD_VERSION_2) {
MLI_UNLOCK(mli);
mld_dispatch_queue_locked(NULL, &qrq, 0);
mld_dispatch_queue_locked(NULL, &scq, 0);
VERIFY(qrq.ifq_len == 0);
VERIFY(scq.ifq_len == 0);
MLI_LOCK(mli);
}
/*
* In case there are still any pending membership reports
* which didn't get drained at version change time.
*/
IF_DRAIN(&mli->mli_v1q);
/*
* Release all deferred inm records, and drain any locally
* enqueued packets; do it even if the current MLD version
* for the link is no longer MLDv2, in order to handle the
* version change case.
*/
mld_flush_relq(mli, (struct mld_in6m_relhead *)&in6m_dthead);
mli->mli_flags |= MLIF_PROCESSED;
MLI_UNLOCK(mli);
MLI_REMREF(mli);
IF_DRAIN(&qrq);
IF_DRAIN(&scq);
if (genid != mld_mli_list_genid) {
MLD_PRINTF(("%s: MLD information list changed "
"in the middle of iteration! Restart iteration.\n",
__func__));
mli = LIST_FIRST(&mli_head);
genid = mld_mli_list_genid;
} else {
mli = LIST_NEXT(mli, mli_link);
}
}
LIST_FOREACH(mli, &mli_head, mli_link)
mli->mli_flags &= ~MLIF_PROCESSED;
out_locked:
/* re-arm the timer if there's work to do */
if (fast) {
mld_fast_timeout_run = false;
} else {
mld_timeout_run = false;
}
mld_sched_timeout();
MLD_UNLOCK();
/* Now that we're dropped all locks, release detached records */
MLD_REMOVE_DETACHED_IN6M(&in6m_dthead);
}
static void
mld_sched_timeout(void)
{
static thread_call_t mld_timeout_tcall;
uint64_t deadline = 0, leeway = 0;
MLD_LOCK_ASSERT_HELD();
if (mld_timeout_tcall == NULL) {
mld_timeout_tcall =
thread_call_allocate_with_options(mld_timeout,
NULL,
THREAD_CALL_PRIORITY_KERNEL,
THREAD_CALL_OPTIONS_ONCE);
}
if (!mld_timeout_run &&
(querier_present_timers_running6 || current_state_timers_running6 ||
interface_timers_running6 || state_change_timers_running6)) {
mld_timeout_run = true;
clock_interval_to_deadline(mld_timeout_delay, NSEC_PER_MSEC,
&deadline);
clock_interval_to_absolutetime_interval(mld_timeout_leeway,
NSEC_PER_MSEC, &leeway);
thread_call_enter_delayed_with_leeway(mld_timeout_tcall, NULL,
deadline, leeway,
THREAD_CALL_DELAY_LEEWAY);
}
}
static void
mld_sched_fast_timeout(void)
{
static thread_call_t mld_fast_timeout_tcall;
MLD_LOCK_ASSERT_HELD();
if (mld_fast_timeout_tcall == NULL) {
mld_fast_timeout_tcall =
thread_call_allocate_with_options(mld_timeout,
mld_sched_fast_timeout,
THREAD_CALL_PRIORITY_KERNEL,
THREAD_CALL_OPTIONS_ONCE);
}
if (!mld_fast_timeout_run &&
(current_state_timers_running6 || state_change_timers_running6)) {
mld_fast_timeout_run = true;
thread_call_enter(mld_fast_timeout_tcall);
}
}
/*
* Appends an in6_multi to the list to be released later.
*
* Caller must be holding mli_lock.
*/
static void
mld_append_relq(struct mld_ifinfo *mli, struct in6_multi *inm)
{
MLI_LOCK_ASSERT_HELD(mli);
if (inm->in6m_in_nrele) {
os_log_debug(OS_LOG_DEFAULT, "%s: inm %llx already on relq ifp %s\n",
__func__, (uint64_t)VM_KERNEL_ADDRPERM(inm),
mli->mli_ifp != NULL ? if_name(mli->mli_ifp) : "<null>");
return;
}
os_log_debug(OS_LOG_DEFAULT, "%s: adding inm %llx on relq ifp %s\n",
__func__, (uint64_t)VM_KERNEL_ADDRPERM(inm),
mli->mli_ifp != NULL ? if_name(mli->mli_ifp) : "<null>");
inm->in6m_in_nrele = true;
SLIST_INSERT_HEAD(&mli->mli_relinmhead, inm, in6m_nrele);
}
/*
* Free the in6_multi reference(s) for this MLD lifecycle.
*
* Caller must be holding mli_lock.
*/
static void
mld_flush_relq(struct mld_ifinfo *mli, struct mld_in6m_relhead *in6m_dthead)
{
struct in6_multi *inm;
SLIST_HEAD(, in6_multi) temp_relinmhead;
/*
* Before dropping the mli_lock, copy all the items in the
* release list to a temporary list to prevent other threads
* from changing mli_relinmhead while we are traversing it.
*/
MLI_LOCK_ASSERT_HELD(mli);
SLIST_INIT(&temp_relinmhead);
while ((inm = SLIST_FIRST(&mli->mli_relinmhead)) != NULL) {
SLIST_REMOVE_HEAD(&mli->mli_relinmhead, in6m_nrele);
SLIST_INSERT_HEAD(&temp_relinmhead, inm, in6m_nrele);
}
MLI_UNLOCK(mli);
in6_multihead_lock_exclusive();
while ((inm = SLIST_FIRST(&temp_relinmhead)) != NULL) {
int lastref;
SLIST_REMOVE_HEAD(&temp_relinmhead, in6m_nrele);
IN6M_LOCK(inm);
os_log_debug(OS_LOG_DEFAULT, "%s: flushing inm %llx on relq ifp %s\n",
__func__, (uint64_t)VM_KERNEL_ADDRPERM(inm),
inm->in6m_ifp != NULL ? if_name(inm->in6m_ifp) : "<null>");
VERIFY(inm->in6m_in_nrele == true);
inm->in6m_in_nrele = false;
VERIFY(inm->in6m_nrelecnt != 0);
inm->in6m_nrelecnt--;
lastref = in6_multi_detach(inm);
VERIFY(!lastref || (!(inm->in6m_debug & IFD_ATTACHED) &&
inm->in6m_reqcnt == 0));
IN6M_UNLOCK(inm);
/* from mli_relinmhead */
IN6M_REMREF(inm);
/* from in6_multihead_list */
if (lastref) {
/*
* Defer releasing our final reference, as we
* are holding the MLD lock at this point, and
* we could end up with locking issues later on
* (while issuing SIOCDELMULTI) when this is the
* final reference count. Let the caller do it
* when it is safe.
*/
MLD_ADD_DETACHED_IN6M(in6m_dthead, inm);
}
}
in6_multihead_lock_done();
MLI_LOCK(mli);
}
/*
* Update host report group timer.
* Will update the global pending timer flags.
*/
static void
mld_v1_process_group_timer(struct in6_multi *inm, const int mld_version)
{
#pragma unused(mld_version)
int report_timer_expired;
MLD_LOCK_ASSERT_HELD();
IN6M_LOCK_ASSERT_HELD(inm);
MLI_LOCK_ASSERT_HELD(inm->in6m_mli);
if (inm->in6m_timer == 0) {
report_timer_expired = 0;
} else if (--inm->in6m_timer == 0) {
report_timer_expired = 1;
} else {
current_state_timers_running6 = 1;
/* caller will schedule timer */
return;
}
switch (inm->in6m_state) {
case MLD_NOT_MEMBER:
case MLD_SILENT_MEMBER:
case MLD_IDLE_MEMBER:
case MLD_LAZY_MEMBER:
case MLD_SLEEPING_MEMBER:
case MLD_AWAKENING_MEMBER:
break;
case MLD_REPORTING_MEMBER:
if (report_timer_expired) {
inm->in6m_state = MLD_IDLE_MEMBER;
(void) mld_v1_transmit_report(inm,
MLD_LISTENER_REPORT);
IN6M_LOCK_ASSERT_HELD(inm);
MLI_LOCK_ASSERT_HELD(inm->in6m_mli);
}
break;
case MLD_G_QUERY_PENDING_MEMBER:
case MLD_SG_QUERY_PENDING_MEMBER:
case MLD_LEAVING_MEMBER:
break;
}
}
/*
* Update a group's timers for MLDv2.
* Will update the global pending timer flags.
* Note: Unlocked read from mli.
*/
static void
mld_v2_process_group_timers(struct mld_ifinfo *mli,
struct ifqueue *qrq, struct ifqueue *scq,
struct in6_multi *inm, const int uri_sec)
{
int query_response_timer_expired;
int state_change_retransmit_timer_expired;
MLD_LOCK_ASSERT_HELD();
IN6M_LOCK_ASSERT_HELD(inm);
MLI_LOCK_ASSERT_HELD(mli);
VERIFY(mli == inm->in6m_mli);
query_response_timer_expired = 0;
state_change_retransmit_timer_expired = 0;
/*
* During a transition from compatibility mode back to MLDv2,
* a group record in REPORTING state may still have its group
* timer active. This is a no-op in this function; it is easier
* to deal with it here than to complicate the timeout path.
*/
if (inm->in6m_timer == 0) {
query_response_timer_expired = 0;
} else if (--inm->in6m_timer == 0) {
query_response_timer_expired = 1;
} else {
current_state_timers_running6 = 1;
/* caller will schedule timer */
}
if (inm->in6m_sctimer == 0) {
state_change_retransmit_timer_expired = 0;
} else if (--inm->in6m_sctimer == 0) {
state_change_retransmit_timer_expired = 1;
} else {
state_change_timers_running6 = 1;
/* caller will schedule timer */
}
/* We are in timer callback, so be quick about it. */
if (!state_change_retransmit_timer_expired &&
!query_response_timer_expired) {
return;
}
switch (inm->in6m_state) {
case MLD_NOT_MEMBER:
case MLD_SILENT_MEMBER:
case MLD_SLEEPING_MEMBER:
case MLD_LAZY_MEMBER:
case MLD_AWAKENING_MEMBER:
case MLD_IDLE_MEMBER:
break;
case MLD_G_QUERY_PENDING_MEMBER:
case MLD_SG_QUERY_PENDING_MEMBER:
/*
* Respond to a previously pending Group-Specific
* or Group-and-Source-Specific query by enqueueing
* the appropriate Current-State report for
* immediate transmission.
*/
if (query_response_timer_expired) {
int retval;
retval = mld_v2_enqueue_group_record(qrq, inm, 0, 1,
(inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER),
0);
MLD_PRINTF(("%s: enqueue record = %d\n",
__func__, retval));
inm->in6m_state = MLD_REPORTING_MEMBER;
in6m_clear_recorded(inm);
}
OS_FALLTHROUGH;
case MLD_REPORTING_MEMBER:
case MLD_LEAVING_MEMBER:
if (state_change_retransmit_timer_expired) {
/*
* State-change retransmission timer fired.
* If there are any further pending retransmissions,
* set the global pending state-change flag, and
* reset the timer.
*/
if (--inm->in6m_scrv > 0) {
inm->in6m_sctimer = (uint16_t)uri_sec;
state_change_timers_running6 = 1;
/* caller will schedule timer */
}
/*
* Retransmit the previously computed state-change
* report. If there are no further pending
* retransmissions, the mbuf queue will be consumed.
* Update T0 state to T1 as we have now sent
* a state-change.
*/
(void) mld_v2_merge_state_changes(inm, scq);
in6m_commit(inm);
MLD_PRINTF(("%s: T1 -> T0 for %s/%s\n", __func__,
ip6_sprintf(&inm->in6m_addr),
if_name(inm->in6m_ifp)));
/*
* If we are leaving the group for good, make sure
* we release MLD's reference to it.
* This release must be deferred using a SLIST,
* as we are called from a loop which traverses
* the in_ifmultiaddr TAILQ.
*/
if (inm->in6m_state == MLD_LEAVING_MEMBER &&
inm->in6m_scrv == 0) {
inm->in6m_state = MLD_NOT_MEMBER;
/*
* A reference has already been held in
* mld_final_leave() for this inm, so
* no need to hold another one. We also
* bumped up its request count then, so
* that it stays in in6_multihead. Both
* of them will be released when it is
* dequeued later on.
*/
VERIFY(inm->in6m_nrelecnt != 0);
mld_append_relq(mli, inm);
}
}
break;
}
}
/*
* Switch to a different version on the given interface,
* as per Section 9.12.
*/
static uint32_t
mld_set_version(struct mld_ifinfo *mli, const int mld_version)
{
int old_version_timer;
MLI_LOCK_ASSERT_HELD(mli);
os_log(OS_LOG_DEFAULT, "%s: switching to v%d on ifp %s\n", __func__,
mld_version, if_name(mli->mli_ifp));
if (mld_version == MLD_VERSION_1) {
/*
* Compute the "Older Version Querier Present" timer as per
* Section 9.12, in seconds.
*/
old_version_timer = (mli->mli_rv * mli->mli_qi) + mli->mli_qri;
mli->mli_v1_timer = old_version_timer;
}
if (mli->mli_v1_timer > 0 && mli->mli_version != MLD_VERSION_1) {
mli->mli_version = MLD_VERSION_1;
mld_v2_cancel_link_timers(mli);
}
MLI_LOCK_ASSERT_HELD(mli);
return mli->mli_v1_timer;
}
/*
* Cancel pending MLDv2 timers for the given link and all groups
* joined on it; state-change, general-query, and group-query timers.
*
* Only ever called on a transition from v2 to Compatibility mode. Kill
* the timers stone dead (this may be expensive for large N groups), they
* will be restarted if Compatibility Mode deems that they must be due to
* query processing.
*/
static void
mld_v2_cancel_link_timers(struct mld_ifinfo *mli)
{
struct ifnet *ifp;
struct in6_multi *inm;
struct in6_multistep step;
MLI_LOCK_ASSERT_HELD(mli);
MLD_PRINTF(("%s: cancel v2 timers on ifp 0x%llx(%s)\n", __func__,
(uint64_t)VM_KERNEL_ADDRPERM(mli->mli_ifp), if_name(mli->mli_ifp)));
/*
* Stop the v2 General Query Response on this link stone dead.
* If timer is woken up due to interface_timers_running6,
* the flag will be cleared if there are no pending link timers.
*/
mli->mli_v2_timer = 0;
/*
* Now clear the current-state and state-change report timers
* for all memberships scoped to this link.
*/
ifp = mli->mli_ifp;
MLI_UNLOCK(mli);
in6_multihead_lock_shared();
IN6_FIRST_MULTI(step, inm);
while (inm != NULL) {
IN6M_LOCK(inm);
if (inm->in6m_ifp != ifp) {
goto next;
}
switch (inm->in6m_state) {
case MLD_NOT_MEMBER:
case MLD_SILENT_MEMBER:
case MLD_IDLE_MEMBER:
case MLD_LAZY_MEMBER:
case MLD_SLEEPING_MEMBER:
case MLD_AWAKENING_MEMBER:
/*
* These states are either not relevant in v2 mode,
* or are unreported. Do nothing.
*/
break;
case MLD_LEAVING_MEMBER:
/*
* If we are leaving the group and switching
* version, we need to release the final
* reference held for issuing the INCLUDE {}.
* During mld_final_leave(), we bumped up both the
* request and reference counts. Since we cannot
* call in6_multi_detach() here, defer this task to
* the timer routine.
*/
VERIFY(inm->in6m_nrelecnt != 0);
MLI_LOCK(mli);
mld_append_relq(mli, inm);
MLI_UNLOCK(mli);
OS_FALLTHROUGH;
case MLD_G_QUERY_PENDING_MEMBER:
case MLD_SG_QUERY_PENDING_MEMBER:
in6m_clear_recorded(inm);
OS_FALLTHROUGH;
case MLD_REPORTING_MEMBER:
inm->in6m_state = MLD_REPORTING_MEMBER;
break;
}
/*
* Always clear state-change and group report timers.
* Free any pending MLDv2 state-change records.
*/
inm->in6m_sctimer = 0;
inm->in6m_timer = 0;
IF_DRAIN(&inm->in6m_scq);
next:
IN6M_UNLOCK(inm);
IN6_NEXT_MULTI(step, inm);
}
in6_multihead_lock_done();
MLI_LOCK(mli);
}
/*
* Update the Older Version Querier Present timers for a link.
* See Section 9.12 of RFC 3810.
*/
static void
mld_v1_process_querier_timers(struct mld_ifinfo *mli)
{
MLI_LOCK_ASSERT_HELD(mli);
if (mld_v2enable && mli->mli_version != MLD_VERSION_2 &&
--mli->mli_v1_timer == 0) {
/*
* MLDv1 Querier Present timer expired; revert to MLDv2.
*/
os_log(OS_LOG_DEFAULT, "%s: transition from v%d -> v%d on %s\n",
__func__, mli->mli_version, MLD_VERSION_2,
if_name(mli->mli_ifp));
mli->mli_version = MLD_VERSION_2;
}
}
/*
* Transmit an MLDv1 report immediately.
*/
static int
mld_v1_transmit_report(struct in6_multi *in6m, const uint8_t type)
{
struct ifnet *ifp;
struct in6_ifaddr *ia;
struct ip6_hdr *ip6;
struct mbuf *mh, *md;
struct mld_hdr *mld;
int error = 0;
IN6M_LOCK_ASSERT_HELD(in6m);
MLI_LOCK_ASSERT_HELD(in6m->in6m_mli);
ifp = in6m->in6m_ifp;
/* ia may be NULL if link-local address is tentative. */
ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY | IN6_IFF_ANYCAST);
MGETHDR(mh, M_DONTWAIT, MT_HEADER);
if (mh == NULL) {
if (ia != NULL) {
ifa_remref(&ia->ia_ifa);
}
return ENOMEM;
}
MGET(md, M_DONTWAIT, MT_DATA);
if (md == NULL) {
m_free(mh);
if (ia != NULL) {
ifa_remref(&ia->ia_ifa);
}
return ENOMEM;
}
mh->m_next = md;
/*
* FUTURE: Consider increasing alignment by ETHER_HDR_LEN, so
* that ether_output() does not need to allocate another mbuf
* for the header in the most common case.
*/
MH_ALIGN(mh, sizeof(struct ip6_hdr));
mh->m_pkthdr.len = sizeof(struct ip6_hdr) + sizeof(struct mld_hdr);
mh->m_len = sizeof(struct ip6_hdr);
ip6 = mtod(mh, struct ip6_hdr *);
ip6->ip6_flow = 0;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
ip6->ip6_nxt = IPPROTO_ICMPV6;
if (ia != NULL) {
IFA_LOCK(&ia->ia_ifa);
}
ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
ip6_output_setsrcifscope(mh, IFSCOPE_NONE, ia);
if (ia != NULL) {
IFA_UNLOCK(&ia->ia_ifa);
ifa_remref(&ia->ia_ifa);
ia = NULL;
}
ip6->ip6_dst = in6m->in6m_addr;
ip6_output_setdstifscope(mh, in6m->ifscope, NULL);
md->m_len = sizeof(struct mld_hdr);
mld = mtod(md, struct mld_hdr *);
mld->mld_type = type;
mld->mld_code = 0;
mld->mld_cksum = 0;
mld->mld_maxdelay = 0;
mld->mld_reserved = 0;
mld->mld_addr = in6m->in6m_addr;
in6_clearscope(&mld->mld_addr);
mld->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6,
sizeof(struct ip6_hdr), sizeof(struct mld_hdr));
mld_save_context(mh, ifp);
mh->m_flags |= M_MLDV1;
/*
* Due to the fact that at this point we are possibly holding
* in6_multihead_lock in shared or exclusive mode, we can't call
* mld_dispatch_packet() here since that will eventually call
* ip6_output(), which will try to lock in6_multihead_lock and cause
* a deadlock.
* Instead we defer the work to the mld_timeout() thread, thus
* avoiding unlocking in_multihead_lock here.
*/
if (IF_QFULL(&in6m->in6m_mli->mli_v1q)) {
os_log_error(OS_LOG_DEFAULT, "%s: v1 outbound queue full\n", __func__);
error = ENOMEM;
m_freem(mh);
} else {
IF_ENQUEUE(&in6m->in6m_mli->mli_v1q, mh);
VERIFY(error == 0);
}
return error;
}
/*
* Process a state change from the upper layer for the given IPv6 group.
*
* Each socket holds a reference on the in6_multi in its own ip_moptions.
* The socket layer will have made the necessary updates to.the group
* state, it is now up to MLD to issue a state change report if there
* has been any change between T0 (when the last state-change was issued)
* and T1 (now).
*
* We use the MLDv2 state machine at group level. The MLd module
* however makes the decision as to which MLD protocol version to speak.
* A state change *from* INCLUDE {} always means an initial join.
* A state change *to* INCLUDE {} always means a final leave.
*
* If delay is non-zero, and the state change is an initial multicast
* join, the state change report will be delayed by 'delay' ticks
* in units of seconds if MLDv1 is active on the link; otherwise
* the initial MLDv2 state change report will be delayed by whichever
* is sooner, a pending state-change timer or delay itself.
*/
int
mld_change_state(struct in6_multi *inm, struct mld_tparams *mtp,
const int delay)
{
struct mld_ifinfo *mli;
struct ifnet *ifp;
int error = 0;
VERIFY(mtp != NULL);
bzero(mtp, sizeof(*mtp));
IN6M_LOCK_ASSERT_HELD(inm);
VERIFY(inm->in6m_mli != NULL);
MLI_LOCK_ASSERT_NOTHELD(inm->in6m_mli);
/*
* Try to detect if the upper layer just asked us to change state
* for an interface which has now gone away.
*/
VERIFY(inm->in6m_ifma != NULL);
ifp = inm->in6m_ifma->ifma_ifp;
/*
* Sanity check that netinet6's notion of ifp is the same as net's.
*/
VERIFY(inm->in6m_ifp == ifp);
mli = MLD_IFINFO(ifp);
VERIFY(mli != NULL);
/*
* If we detect a state transition to or from MCAST_UNDEFINED
* for this group, then we are starting or finishing an MLD
* life cycle for this group.
*/
if (inm->in6m_st[1].iss_fmode != inm->in6m_st[0].iss_fmode) {
MLD_PRINTF(("%s: inm transition %d -> %d\n", __func__,
inm->in6m_st[0].iss_fmode, inm->in6m_st[1].iss_fmode));
if (inm->in6m_st[0].iss_fmode == MCAST_UNDEFINED) {
MLD_PRINTF(("%s: initial join\n", __func__));
error = mld_initial_join(inm, mli, mtp, delay);
goto out;
} else if (inm->in6m_st[1].iss_fmode == MCAST_UNDEFINED) {
MLD_PRINTF(("%s: final leave\n", __func__));
mld_final_leave(inm, mli, mtp);
goto out;
}
} else {
MLD_PRINTF(("%s: filter set change\n", __func__));
}
error = mld_handle_state_change(inm, mli, mtp);
out:
return error;
}
/*
* Perform the initial join for an MLD group.
*
* When joining a group:
* If the group should have its MLD traffic suppressed, do nothing.
* MLDv1 starts sending MLDv1 host membership reports.
* MLDv2 will schedule an MLDv2 state-change report containing the
* initial state of the membership.
*
* If the delay argument is non-zero, then we must delay sending the
* initial state change for delay ticks (in units of seconds).
*/
static int
mld_initial_join(struct in6_multi *inm, struct mld_ifinfo *mli,
struct mld_tparams *mtp, const int delay)
{
struct ifnet *ifp;
struct ifqueue *ifq;
int error, retval, syncstates;
int odelay;
IN6M_LOCK_ASSERT_HELD(inm);
MLI_LOCK_ASSERT_NOTHELD(mli);
VERIFY(mtp != NULL);
MLD_PRINTF(("%s: initial join %s on ifp 0x%llx(%s)\n",
__func__, ip6_sprintf(&inm->in6m_addr),
(uint64_t)VM_KERNEL_ADDRPERM(inm->in6m_ifp),
if_name(inm->in6m_ifp)));
error = 0;
syncstates = 1;
ifp = inm->in6m_ifp;
MLI_LOCK(mli);
VERIFY(mli->mli_ifp == ifp);
/*
* Avoid MLD if group is :
* 1. Joined on loopback, OR
* 2. On a link that is marked MLIF_SILENT
* 3. rdar://problem/19227650 Is link local scoped and
* on cellular interface
* 4. Is a type that should not be reported (node local
* or all node link local multicast.
* All other groups enter the appropriate state machine
* for the version in use on this link.
*/
if ((ifp->if_flags & IFF_LOOPBACK) ||
(mli->mli_flags & MLIF_SILENT) ||
(IFNET_IS_CELLULAR(ifp) &&
(IN6_IS_ADDR_MC_LINKLOCAL(&inm->in6m_addr) || IN6_IS_ADDR_MC_UNICAST_BASED_LINKLOCAL(&inm->in6m_addr))) ||
!mld_is_addr_reported(&inm->in6m_addr)) {
MLD_PRINTF(("%s: not kicking state machine for silent group\n",
__func__));
inm->in6m_state = MLD_SILENT_MEMBER;
inm->in6m_timer = 0;
} else {
/*
* Deal with overlapping in6_multi lifecycle.
* If this group was LEAVING, then make sure
* we drop the reference we picked up to keep the
* group around for the final INCLUDE {} enqueue.
* Since we cannot call in6_multi_detach() here,
* defer this task to the timer routine.
*/
if (mli->mli_version == MLD_VERSION_2 &&
inm->in6m_state == MLD_LEAVING_MEMBER) {
VERIFY(inm->in6m_nrelecnt != 0);
mld_append_relq(mli, inm);
}
inm->in6m_state = MLD_REPORTING_MEMBER;
switch (mli->mli_version) {
case MLD_VERSION_1:
/*
* If a delay was provided, only use it if
* it is greater than the delay normally
* used for an MLDv1 state change report,
* and delay sending the initial MLDv1 report
* by not transitioning to the IDLE state.
*/
odelay = MLD_RANDOM_DELAY(MLD_V1_MAX_RI);
if (delay) {
inm->in6m_timer = max(delay, odelay);
mtp->cst = 1;
} else {
inm->in6m_state = MLD_IDLE_MEMBER;
error = mld_v1_transmit_report(inm,
MLD_LISTENER_REPORT);
IN6M_LOCK_ASSERT_HELD(inm);
MLI_LOCK_ASSERT_HELD(mli);
if (error == 0) {
inm->in6m_timer = odelay;
mtp->cst = 1;
}
}
break;
case MLD_VERSION_2:
/*
* Defer update of T0 to T1, until the first copy
* of the state change has been transmitted.
*/
syncstates = 0;
/*
* Immediately enqueue a State-Change Report for
* this interface, freeing any previous reports.
* Don't kick the timers if there is nothing to do,
* or if an error occurred.
*/
ifq = &inm->in6m_scq;
IF_DRAIN(ifq);
retval = mld_v2_enqueue_group_record(ifq, inm, 1,
0, 0, (mli->mli_flags & MLIF_USEALLOW));
mtp->cst = (ifq->ifq_len > 0);
MLD_PRINTF(("%s: enqueue record = %d\n",
__func__, retval));
if (retval <= 0) {
error = retval * -1;
break;
}
/*
* Schedule transmission of pending state-change
* report up to RV times for this link. The timer
* will fire at the next mld_timeout (1 second)),
* giving us an opportunity to merge the reports.
*
* If a delay was provided to this function, only
* use this delay if sooner than the existing one.
*/
VERIFY(mli->mli_rv > 1);
inm->in6m_scrv = (uint16_t)mli->mli_rv;
if (delay) {
if (inm->in6m_sctimer > 1) {
inm->in6m_sctimer =
MIN(inm->in6m_sctimer, (uint16_t)delay);
} else {
inm->in6m_sctimer = (uint16_t)delay;
}
} else {
inm->in6m_sctimer = 1;
}
mtp->sct = 1;
error = 0;
break;
}
}
MLI_UNLOCK(mli);
/*
* Only update the T0 state if state change is atomic,
* i.e. we don't need to wait for a timer to fire before we
* can consider the state change to have been communicated.
*/
if (syncstates) {
in6m_commit(inm);
MLD_PRINTF(("%s: T1 -> T0 for %s/%s\n", __func__,
ip6_sprintf(&inm->in6m_addr),
if_name(inm->in6m_ifp)));
}
return error;
}
/*
* Issue an intermediate state change during the life-cycle.
*/
static int
mld_handle_state_change(struct in6_multi *inm, struct mld_ifinfo *mli,
struct mld_tparams *mtp)
{
struct ifnet *ifp;
int retval = 0;
IN6M_LOCK_ASSERT_HELD(inm);
MLI_LOCK_ASSERT_NOTHELD(mli);
VERIFY(mtp != NULL);
MLD_PRINTF(("%s: state change for %s on ifp 0x%llx(%s)\n",
__func__, ip6_sprintf(&inm->in6m_addr),
(uint64_t)VM_KERNEL_ADDRPERM(inm->in6m_ifp),
if_name(inm->in6m_ifp)));
ifp = inm->in6m_ifp;
MLI_LOCK(mli);
VERIFY(mli->mli_ifp == ifp);
if ((ifp->if_flags & IFF_LOOPBACK) ||
(mli->mli_flags & MLIF_SILENT) ||
!mld_is_addr_reported(&inm->in6m_addr) ||
(mli->mli_version != MLD_VERSION_2)) {
MLI_UNLOCK(mli);
if (!mld_is_addr_reported(&inm->in6m_addr)) {
MLD_PRINTF(("%s: not kicking state machine for silent "
"group\n", __func__));
}
MLD_PRINTF(("%s: nothing to do\n", __func__));
in6m_commit(inm);
MLD_PRINTF(("%s: T1 -> T0 for %s/%s\n", __func__,
ip6_sprintf(&inm->in6m_addr),
if_name(inm->in6m_ifp)));
goto done;
}
IF_DRAIN(&inm->in6m_scq);
retval = mld_v2_enqueue_group_record(&inm->in6m_scq, inm, 1, 0, 0,
(mli->mli_flags & MLIF_USEALLOW));
mtp->cst = (inm->in6m_scq.ifq_len > 0);
MLD_PRINTF(("%s: enqueue record = %d\n", __func__, retval));
if (retval <= 0) {
MLI_UNLOCK(mli);
retval *= -1;
goto done;
} else {
retval = 0;
}
/*
* If record(s) were enqueued, start the state-change
* report timer for this group.
*/
inm->in6m_scrv = (uint16_t)mli->mli_rv;
inm->in6m_sctimer = 1;
mtp->sct = 1;
MLI_UNLOCK(mli);
done:
return retval;
}
/*
* Perform the final leave for a multicast address.
*
* When leaving a group:
* MLDv1 sends a DONE message, if and only if we are the reporter.
* MLDv2 enqueues a state-change report containing a transition
* to INCLUDE {} for immediate transmission.
*/
static void
mld_final_leave(struct in6_multi *inm, struct mld_ifinfo *mli,
struct mld_tparams *mtp)
{
int syncstates = 1;
IN6M_LOCK_ASSERT_HELD(inm);
MLI_LOCK_ASSERT_NOTHELD(mli);
VERIFY(mtp != NULL);
MLD_PRINTF(("%s: final leave %s on ifp 0x%llx(%s)\n",
__func__, ip6_sprintf(&inm->in6m_addr),
(uint64_t)VM_KERNEL_ADDRPERM(inm->in6m_ifp),
if_name(inm->in6m_ifp)));
switch (inm->in6m_state) {
case MLD_NOT_MEMBER:
case MLD_SILENT_MEMBER:
case MLD_LEAVING_MEMBER:
/* Already leaving or left; do nothing. */
MLD_PRINTF(("%s: not kicking state machine for silent group\n",
__func__));
break;
case MLD_REPORTING_MEMBER:
case MLD_IDLE_MEMBER:
case MLD_G_QUERY_PENDING_MEMBER:
case MLD_SG_QUERY_PENDING_MEMBER:
MLI_LOCK(mli);
if (mli->mli_version == MLD_VERSION_1) {
if (inm->in6m_state == MLD_G_QUERY_PENDING_MEMBER ||
inm->in6m_state == MLD_SG_QUERY_PENDING_MEMBER) {
panic("%s: MLDv2 state reached, not MLDv2 "
"mode\n", __func__);
/* NOTREACHED */
}
/* scheduler timer if enqueue is successful */
mtp->cst = (mld_v1_transmit_report(inm,
MLD_LISTENER_DONE) == 0);
IN6M_LOCK_ASSERT_HELD(inm);
MLI_LOCK_ASSERT_HELD(mli);
inm->in6m_state = MLD_NOT_MEMBER;
} else if (mli->mli_version == MLD_VERSION_2) {
/*
* Stop group timer and all pending reports.
* Immediately enqueue a state-change report
* TO_IN {} to be sent on the next timeout,
* giving us an opportunity to merge reports.
*/
IF_DRAIN(&inm->in6m_scq);
inm->in6m_timer = 0;
inm->in6m_scrv = (uint16_t)mli->mli_rv;
MLD_PRINTF(("%s: Leaving %s/%s with %d "
"pending retransmissions.\n", __func__,
ip6_sprintf(&inm->in6m_addr),
if_name(inm->in6m_ifp),
inm->in6m_scrv));
if (inm->in6m_scrv == 0) {
inm->in6m_state = MLD_NOT_MEMBER;
inm->in6m_sctimer = 0;
} else {
int retval;
/*
* Stick around in the in6_multihead list;
* the final detach will be issued by
* mld_v2_process_group_timers() when
* the retransmit timer expires.
*/
IN6M_ADDREF_LOCKED(inm);
VERIFY(inm->in6m_debug & IFD_ATTACHED);
inm->in6m_reqcnt++;
VERIFY(inm->in6m_reqcnt >= 1);
inm->in6m_nrelecnt++;
VERIFY(inm->in6m_nrelecnt != 0);
retval = mld_v2_enqueue_group_record(
&inm->in6m_scq, inm, 1, 0, 0,
(mli->mli_flags & MLIF_USEALLOW));
mtp->cst = (inm->in6m_scq.ifq_len > 0);
KASSERT(retval != 0,
("%s: enqueue record = %d\n", __func__,
retval));
inm->in6m_state = MLD_LEAVING_MEMBER;
inm->in6m_sctimer = 1;
mtp->sct = 1;
syncstates = 0;
}
}
MLI_UNLOCK(mli);
break;
case MLD_LAZY_MEMBER:
case MLD_SLEEPING_MEMBER:
case MLD_AWAKENING_MEMBER:
/* Our reports are suppressed; do nothing. */
break;
}
if (syncstates) {
in6m_commit(inm);
MLD_PRINTF(("%s: T1 -> T0 for %s/%s\n", __func__,
ip6_sprintf(&inm->in6m_addr),
if_name(inm->in6m_ifp)));
inm->in6m_st[1].iss_fmode = MCAST_UNDEFINED;
MLD_PRINTF(("%s: T1 now MCAST_UNDEFINED for 0x%llx/%s\n",
__func__, (uint64_t)VM_KERNEL_ADDRPERM(&inm->in6m_addr),
if_name(inm->in6m_ifp)));
}
}
/*
* Enqueue an MLDv2 group record to the given output queue.
*
* If is_state_change is zero, a current-state record is appended.
* If is_state_change is non-zero, a state-change report is appended.
*
* If is_group_query is non-zero, an mbuf packet chain is allocated.
* If is_group_query is zero, and if there is a packet with free space
* at the tail of the queue, it will be appended to providing there
* is enough free space.
* Otherwise a new mbuf packet chain is allocated.
*
* If is_source_query is non-zero, each source is checked to see if
* it was recorded for a Group-Source query, and will be omitted if
* it is not both in-mode and recorded.
*
* If use_block_allow is non-zero, state change reports for initial join
* and final leave, on an inclusive mode group with a source list, will be
* rewritten to use the ALLOW_NEW and BLOCK_OLD record types, respectively.
*
* The function will attempt to allocate leading space in the packet
* for the IPv6+ICMP headers to be prepended without fragmenting the chain.
*
* If successful the size of all data appended to the queue is returned,
* otherwise an error code less than zero is returned, or zero if
* no record(s) were appended.
*/
static int
mld_v2_enqueue_group_record(struct ifqueue *ifq, struct in6_multi *inm,
const int is_state_change, const int is_group_query,
const int is_source_query, const int use_block_allow)
{
struct mldv2_record mr;
struct mldv2_record *pmr;
struct ifnet *ifp;
struct ip6_msource *ims, *nims;
mbuf_ref_t m0, m, md;
int error, is_filter_list_change;
int minrec0len, m0srcs, msrcs, nbytes, off;
int record_has_sources;
int now;
uint8_t type;
uint8_t mode;
IN6M_LOCK_ASSERT_HELD(inm);
MLI_LOCK_ASSERT_HELD(inm->in6m_mli);
error = 0;
ifp = inm->in6m_ifp;
is_filter_list_change = 0;
m = NULL;
m0 = NULL;
m0srcs = 0;
msrcs = 0;
nbytes = 0;
nims = NULL;
record_has_sources = 1;
pmr = NULL;
type = MLD_DO_NOTHING;
mode = (uint8_t)inm->in6m_st[1].iss_fmode;
/*
* If we did not transition out of ASM mode during t0->t1,
* and there are no source nodes to process, we can skip
* the generation of source records.
*/
if (inm->in6m_st[0].iss_asm > 0 && inm->in6m_st[1].iss_asm > 0 &&
inm->in6m_nsrc == 0) {
record_has_sources = 0;
}
if (is_state_change) {
/*
* Queue a state change record.
* If the mode did not change, and there are non-ASM
* listeners or source filters present,
* we potentially need to issue two records for the group.
* If there are ASM listeners, and there was no filter
* mode transition of any kind, do nothing.
*
* If we are transitioning to MCAST_UNDEFINED, we need
* not send any sources. A transition to/from this state is
* considered inclusive with some special treatment.
*
* If we are rewriting initial joins/leaves to use
* ALLOW/BLOCK, and the group's membership is inclusive,
* we need to send sources in all cases.
*/
if (mode != inm->in6m_st[0].iss_fmode) {
if (mode == MCAST_EXCLUDE) {
MLD_PRINTF(("%s: change to EXCLUDE\n",
__func__));
type = MLD_CHANGE_TO_EXCLUDE_MODE;
} else {
MLD_PRINTF(("%s: change to INCLUDE\n",
__func__));
if (use_block_allow) {
/*
* XXX
* Here we're interested in state
* edges either direction between
* MCAST_UNDEFINED and MCAST_INCLUDE.
* Perhaps we should just check
* the group state, rather than
* the filter mode.
*/
if (mode == MCAST_UNDEFINED) {
type = MLD_BLOCK_OLD_SOURCES;
} else {
type = MLD_ALLOW_NEW_SOURCES;
}
} else {
type = MLD_CHANGE_TO_INCLUDE_MODE;
if (mode == MCAST_UNDEFINED) {
record_has_sources = 0;
}
}
}
} else {
if (record_has_sources) {
is_filter_list_change = 1;
} else {
type = MLD_DO_NOTHING;
}
}
} else {
/*
* Queue a current state record.
*/
if (mode == MCAST_EXCLUDE) {
type = MLD_MODE_IS_EXCLUDE;
} else if (mode == MCAST_INCLUDE) {
type = MLD_MODE_IS_INCLUDE;
VERIFY(inm->in6m_st[1].iss_asm == 0);
}
}
/*
* Generate the filter list changes using a separate function.
*/
if (is_filter_list_change) {
return mld_v2_enqueue_filter_change(ifq, inm);
}
if (type == MLD_DO_NOTHING) {
MLD_PRINTF(("%s: nothing to do for %s/%s\n",
__func__, ip6_sprintf(&inm->in6m_addr),
if_name(inm->in6m_ifp)));
return 0;
}
/*
* If any sources are present, we must be able to fit at least
* one in the trailing space of the tail packet's mbuf,
* ideally more.
*/
minrec0len = sizeof(struct mldv2_record);
if (record_has_sources) {
minrec0len += sizeof(struct in6_addr);
}
MLD_PRINTF(("%s: queueing %s for %s/%s\n", __func__,
mld_rec_type_to_str(type),
ip6_sprintf(&inm->in6m_addr),
if_name(inm->in6m_ifp)));
/*
* Check if we have a packet in the tail of the queue for this
* group into which the first group record for this group will fit.
* Otherwise allocate a new packet.
* Always allocate leading space for IP6+RA+ICMPV6+REPORT.
* Note: Group records for G/GSR query responses MUST be sent
* in their own packet.
*/
m0 = ifq->ifq_tail;
if (!is_group_query &&
m0 != NULL &&
(m0->m_pkthdr.vt_nrecs + 1 <= MLD_V2_REPORT_MAXRECS) &&
(m0->m_pkthdr.len + minrec0len) <
(ifp->if_mtu - MLD_MTUSPACE)) {
m0srcs = (ifp->if_mtu - m0->m_pkthdr.len -
sizeof(struct mldv2_record)) /
sizeof(struct in6_addr);
m = m0;
MLD_PRINTF(("%s: use existing packet\n", __func__));
} else {
if (IF_QFULL(ifq)) {
os_log_error(OS_LOG_DEFAULT,
"%s: outbound queue full\n", __func__);
return -ENOMEM;
}
m = NULL;
m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
sizeof(struct mldv2_record)) / sizeof(struct in6_addr);
if (!is_state_change && !is_group_query) {
m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
}
if (m == NULL) {
m = m_gethdr(M_DONTWAIT, MT_DATA);
}
if (m == NULL) {
return -ENOMEM;
}
mld_save_context(m, ifp);
MLD_PRINTF(("%s: allocated first packet\n", __func__));
}
/*
* Append group record.
* If we have sources, we don't know how many yet.
*/
mr.mr_type = type;
mr.mr_datalen = 0;
mr.mr_numsrc = 0;
mr.mr_addr = inm->in6m_addr;
in6_clearscope(&mr.mr_addr);
if (!m_append(m, sizeof(struct mldv2_record), (void *)&mr)) {
if (m != m0) {
m_freem(m);
}
os_log_error(OS_LOG_DEFAULT, "%s: m_append() failed.\n", __func__);
return -ENOMEM;
}
nbytes += sizeof(struct mldv2_record);
/*
* Append as many sources as will fit in the first packet.
* If we are appending to a new packet, the chain allocation
* may potentially use clusters; use m_getptr() in this case.
* If we are appending to an existing packet, we need to obtain
* a pointer to the group record after m_append(), in case a new
* mbuf was allocated.
*
* Only append sources which are in-mode at t1. If we are
* transitioning to MCAST_UNDEFINED state on the group, and
* use_block_allow is zero, do not include source entries.
* Otherwise, we need to include this source in the report.
*
* Only report recorded sources in our filter set when responding
* to a group-source query.
*/
if (record_has_sources) {
if (m == m0) {
md = m_last(m);
pmr = (struct mldv2_record *)(mtod(md, uint8_t *) +
md->m_len - nbytes);
} else {
md = m_getptr(m, 0, &off);
pmr = (struct mldv2_record *)(mtod(md, uint8_t *) +
off);
}
msrcs = 0;
RB_FOREACH_SAFE(ims, ip6_msource_tree, &inm->in6m_srcs,
nims) {
MLD_PRINTF(("%s: visit node %s\n", __func__,
ip6_sprintf(&ims->im6s_addr)));
now = im6s_get_mode(inm, ims, 1);
MLD_PRINTF(("%s: node is %d\n", __func__, now));
if ((now != mode) ||
(now == mode &&
(!use_block_allow && mode == MCAST_UNDEFINED))) {
MLD_PRINTF(("%s: skip node\n", __func__));
continue;
}
if (is_source_query && ims->im6s_stp == 0) {
MLD_PRINTF(("%s: skip unrecorded node\n",
__func__));
continue;
}
MLD_PRINTF(("%s: append node\n", __func__));
if (!m_append(m, sizeof(struct in6_addr),
(void *)&ims->im6s_addr)) {
if (m != m0) {
m_freem(m);
}
os_log_error(OS_LOG_DEFAULT,
"%s: m_append() failed\n",
__func__);
return -ENOMEM;
}
nbytes += sizeof(struct in6_addr);
++msrcs;
if (msrcs == m0srcs) {
break;
}
}
MLD_PRINTF(("%s: msrcs is %d this packet\n", __func__,
msrcs));
pmr->mr_numsrc = htons((uint16_t)msrcs);
nbytes += (msrcs * sizeof(struct in6_addr));
}
if (is_source_query && msrcs == 0) {
MLD_PRINTF(("%s: no recorded sources to report\n", __func__));
if (m != m0) {
m_freem(m);
}
return 0;
}
/*
* We are good to go with first packet.
*/
if (m != m0) {
MLD_PRINTF(("%s: enqueueing first packet\n", __func__));
m->m_pkthdr.vt_nrecs = 1;
IF_ENQUEUE(ifq, m);
} else {
m->m_pkthdr.vt_nrecs++;
}
/*
* No further work needed if no source list in packet(s).
*/
if (!record_has_sources) {
return nbytes;
}
/*
* Whilst sources remain to be announced, we need to allocate
* a new packet and fill out as many sources as will fit.
* Always try for a cluster first.
*/
while (nims != NULL) {
if (IF_QFULL(ifq)) {
os_log_error(OS_LOG_DEFAULT, "%s: outbound queue full\n", __func__);
return -ENOMEM;
}
m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
if (m == NULL) {
m = m_gethdr(M_DONTWAIT, MT_DATA);
}
if (m == NULL) {
return -ENOMEM;
}
mld_save_context(m, ifp);
md = m_getptr(m, 0, &off);
pmr = (struct mldv2_record *)(mtod(md, uint8_t *) + off);
MLD_PRINTF(("%s: allocated next packet\n", __func__));
if (!m_append(m, sizeof(struct mldv2_record), (void *)&mr)) {
if (m != m0) {
m_freem(m);
}
os_log_error(OS_LOG_DEFAULT, "%s: m_append() failed.\n", __func__);
return -ENOMEM;
}
m->m_pkthdr.vt_nrecs = 1;
nbytes += sizeof(struct mldv2_record);
m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
sizeof(struct mldv2_record)) / sizeof(struct in6_addr);
msrcs = 0;
RB_FOREACH_FROM(ims, ip6_msource_tree, nims) {
MLD_PRINTF(("%s: visit node %s\n",
__func__, ip6_sprintf(&ims->im6s_addr)));
now = im6s_get_mode(inm, ims, 1);
if ((now != mode) ||
(now == mode &&
(!use_block_allow && mode == MCAST_UNDEFINED))) {
MLD_PRINTF(("%s: skip node\n", __func__));
continue;
}
if (is_source_query && ims->im6s_stp == 0) {
MLD_PRINTF(("%s: skip unrecorded node\n",
__func__));
continue;
}
MLD_PRINTF(("%s: append node\n", __func__));
if (!m_append(m, sizeof(struct in6_addr),
(void *)&ims->im6s_addr)) {
if (m != m0) {
m_freem(m);
}
os_log_error(OS_LOG_DEFAULT, "%s: m_append() failed\n",
__func__);
return -ENOMEM;
}
++msrcs;
if (msrcs == m0srcs) {
break;
}
}
pmr->mr_numsrc = htons((uint16_t)msrcs);
nbytes += (msrcs * sizeof(struct in6_addr));
MLD_PRINTF(("%s: enqueueing next packet\n", __func__));
IF_ENQUEUE(ifq, m);
}
return nbytes;
}
/*
* Type used to mark record pass completion.
* We exploit the fact we can cast to this easily from the
* current filter modes on each ip_msource node.
*/
typedef enum {
REC_NONE = 0x00, /* MCAST_UNDEFINED */
REC_ALLOW = 0x01, /* MCAST_INCLUDE */
REC_BLOCK = 0x02, /* MCAST_EXCLUDE */
REC_FULL = REC_ALLOW | REC_BLOCK
} rectype_t;
/*
* Enqueue an MLDv2 filter list change to the given output queue.
*
* Source list filter state is held in an RB-tree. When the filter list
* for a group is changed without changing its mode, we need to compute
* the deltas between T0 and T1 for each source in the filter set,
* and enqueue the appropriate ALLOW_NEW/BLOCK_OLD records.
*
* As we may potentially queue two record types, and the entire R-B tree
* needs to be walked at once, we break this out into its own function
* so we can generate a tightly packed queue of packets.
*
* XXX This could be written to only use one tree walk, although that makes
* serializing into the mbuf chains a bit harder. For now we do two walks
* which makes things easier on us, and it may or may not be harder on
* the L2 cache.
*
* If successful the size of all data appended to the queue is returned,
* otherwise an error code less than zero is returned, or zero if
* no record(s) were appended.
*/
static int
mld_v2_enqueue_filter_change(struct ifqueue *ifq, struct in6_multi *inm)
{
static const int MINRECLEN =
sizeof(struct mldv2_record) + sizeof(struct in6_addr);
struct ifnet *ifp;
struct mldv2_record mr;
struct mldv2_record *pmr;
struct ip6_msource *ims, *nims;
mbuf_ref_t m, m0, md;
int m0srcs, nbytes, npbytes, off, rsrcs, schanged;
int nallow, nblock;
uint8_t mode, now, then;
rectype_t crt, drt, nrt;
IN6M_LOCK_ASSERT_HELD(inm);
if (inm->in6m_nsrc == 0 ||
(inm->in6m_st[0].iss_asm > 0 && inm->in6m_st[1].iss_asm > 0)) {
return 0;
}
ifp = inm->in6m_ifp; /* interface */
mode = (uint8_t)inm->in6m_st[1].iss_fmode; /* filter mode at t1 */
crt = REC_NONE; /* current group record type */
drt = REC_NONE; /* mask of completed group record types */
nrt = REC_NONE; /* record type for current node */
m0srcs = 0; /* # source which will fit in current mbuf chain */
npbytes = 0; /* # of bytes appended this packet */
nbytes = 0; /* # of bytes appended to group's state-change queue */
rsrcs = 0; /* # sources encoded in current record */
schanged = 0; /* # nodes encoded in overall filter change */
nallow = 0; /* # of source entries in ALLOW_NEW */
nblock = 0; /* # of source entries in BLOCK_OLD */
nims = NULL; /* next tree node pointer */
/*
* For each possible filter record mode.
* The first kind of source we encounter tells us which
* is the first kind of record we start appending.
* If a node transitioned to UNDEFINED at t1, its mode is treated
* as the inverse of the group's filter mode.
*/
while (drt != REC_FULL) {
do {
m0 = ifq->ifq_tail;
if (m0 != NULL &&
(m0->m_pkthdr.vt_nrecs + 1 <=
MLD_V2_REPORT_MAXRECS) &&
(m0->m_pkthdr.len + MINRECLEN) <
(ifp->if_mtu - MLD_MTUSPACE)) {
m = m0;
m0srcs = (ifp->if_mtu - m0->m_pkthdr.len -
sizeof(struct mldv2_record)) /
sizeof(struct in6_addr);
MLD_PRINTF(("%s: use previous packet\n",
__func__));
} else {
m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
if (m == NULL) {
m = m_gethdr(M_DONTWAIT, MT_DATA);
}
if (m == NULL) {
os_log_error(OS_LOG_DEFAULT, "%s: m_get*() failed\n",
__func__);
return -ENOMEM;
}
m->m_pkthdr.vt_nrecs = 0;
mld_save_context(m, ifp);
m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
sizeof(struct mldv2_record)) /
sizeof(struct in6_addr);
npbytes = 0;
MLD_PRINTF(("%s: allocated new packet\n",
__func__));
}
/*
* Append the MLD group record header to the
* current packet's data area.
* Recalculate pointer to free space for next
* group record, in case m_append() allocated
* a new mbuf or cluster.
*/
memset(&mr, 0, sizeof(mr));
mr.mr_addr = inm->in6m_addr;
in6_clearscope(&mr.mr_addr);
if (!m_append(m, sizeof(mr), (void *)&mr)) {
if (m != m0) {
m_freem(m);
}
os_log_error(OS_LOG_DEFAULT, "%s: m_append() failed\n",
__func__);
return -ENOMEM;
}
npbytes += sizeof(struct mldv2_record);
if (m != m0) {
/* new packet; offset in chain */
md = m_getptr(m, npbytes -
sizeof(struct mldv2_record), &off);
pmr = (struct mldv2_record *)(mtod(md,
uint8_t *) + off);
} else {
/* current packet; offset from last append */
md = m_last(m);
pmr = (struct mldv2_record *)(mtod(md,
uint8_t *) + md->m_len -
sizeof(struct mldv2_record));
}
/*
* Begin walking the tree for this record type
* pass, or continue from where we left off
* previously if we had to allocate a new packet.
* Only report deltas in-mode at t1.
* We need not report included sources as allowed
* if we are in inclusive mode on the group,
* however the converse is not true.
*/
rsrcs = 0;
if (nims == NULL) {
nims = RB_MIN(ip6_msource_tree,
&inm->in6m_srcs);
}
RB_FOREACH_FROM(ims, ip6_msource_tree, nims) {
MLD_PRINTF(("%s: visit node %s\n", __func__,
ip6_sprintf(&ims->im6s_addr)));
now = im6s_get_mode(inm, ims, 1);
then = im6s_get_mode(inm, ims, 0);
MLD_PRINTF(("%s: mode: t0 %d, t1 %d\n",
__func__, then, now));
if (now == then) {
MLD_PRINTF(("%s: skip unchanged\n",
__func__));
continue;
}
if (mode == MCAST_EXCLUDE &&
now == MCAST_INCLUDE) {
MLD_PRINTF(("%s: skip IN src on EX "
"group\n", __func__));
continue;
}
nrt = (rectype_t)now;
if (nrt == REC_NONE) {
nrt = (rectype_t)(~mode & REC_FULL);
}
if (schanged++ == 0) {
crt = nrt;
} else if (crt != nrt) {
continue;
}
if (!m_append(m, sizeof(struct in6_addr),
(void *)&ims->im6s_addr)) {
if (m != m0) {
m_freem(m);
}
os_log_error(OS_LOG_DEFAULT, "%s: m_append() failed\n",
__func__);
return -ENOMEM;
}
nallow += !!(crt == REC_ALLOW);
nblock += !!(crt == REC_BLOCK);
if (++rsrcs == m0srcs) {
break;
}
}
/*
* If we did not append any tree nodes on this
* pass, back out of allocations.
*/
if (rsrcs == 0) {
npbytes -= sizeof(struct mldv2_record);
if (m != m0) {
MLD_PRINTF(("%s: m_free(m)\n",
__func__));
m_freem(m);
} else {
MLD_PRINTF(("%s: m_adj(m, -mr)\n",
__func__));
m_adj(m, -((int)sizeof(
struct mldv2_record)));
}
continue;
}
npbytes += (rsrcs * sizeof(struct in6_addr));
if (crt == REC_ALLOW) {
pmr->mr_type = MLD_ALLOW_NEW_SOURCES;
} else if (crt == REC_BLOCK) {
pmr->mr_type = MLD_BLOCK_OLD_SOURCES;
}
pmr->mr_numsrc = htons((uint16_t)rsrcs);
/*
* Count the new group record, and enqueue this
* packet if it wasn't already queued.
*/
m->m_pkthdr.vt_nrecs++;
if (m != m0) {
IF_ENQUEUE(ifq, m);
}
nbytes += npbytes;
} while (nims != NULL);
drt |= crt;
crt = (~crt & REC_FULL);
}
MLD_PRINTF(("%s: queued %d ALLOW_NEW, %d BLOCK_OLD\n", __func__,
nallow, nblock));
return nbytes;
}
static int
mld_v2_merge_state_changes(struct in6_multi *inm, struct ifqueue *ifscq)
{
struct ifqueue *gq;
mbuf_ref_t m; /* pending state-change */
mbuf_ref_t m0; /* copy of pending state-change */
mbuf_ref_t mt; /* last state-change in packet */
mbuf_ref_t n;
int docopy, domerge;
u_int recslen;
IN6M_LOCK_ASSERT_HELD(inm);
docopy = 0;
domerge = 0;
recslen = 0;
/*
* If there are further pending retransmissions, make a writable
* copy of each queued state-change message before merging.
*/
if (inm->in6m_scrv > 0) {
docopy = 1;
}
gq = &inm->in6m_scq;
#ifdef MLD_DEBUG
if (gq->ifq_head == NULL) {
MLD_PRINTF(("%s: WARNING: queue for inm 0x%llx is empty\n",
__func__, (uint64_t)VM_KERNEL_ADDRPERM(inm)));
}
#endif
/*
* Use IF_REMQUEUE() instead of IF_DEQUEUE() below, since the
* packet might not always be at the head of the ifqueue.
*/
m = gq->ifq_head;
while (m != NULL) {
/*
* Only merge the report into the current packet if
* there is sufficient space to do so; an MLDv2 report
* packet may only contain 65,535 group records.
* Always use a simple mbuf chain concatentation to do this,
* as large state changes for single groups may have
* allocated clusters.
*/
domerge = 0;
mt = ifscq->ifq_tail;
if (mt != NULL) {
recslen = m_length(m);
if ((mt->m_pkthdr.vt_nrecs +
m->m_pkthdr.vt_nrecs <=
MLD_V2_REPORT_MAXRECS) &&
(mt->m_pkthdr.len + recslen <=
(inm->in6m_ifp->if_mtu - MLD_MTUSPACE))) {
domerge = 1;
}
}
if (!domerge && IF_QFULL(gq)) {
os_log_info(OS_LOG_DEFAULT, "%s: outbound queue full",
__func__);
n = m->m_nextpkt;
if (!docopy) {
IF_REMQUEUE(gq, m);
m_freem(m);
}
m = n;
continue;
}
if (!docopy) {
MLD_PRINTF(("%s: dequeueing 0x%llx\n", __func__,
(uint64_t)VM_KERNEL_ADDRPERM(m)));
n = m->m_nextpkt;
IF_REMQUEUE(gq, m);
m0 = m;
m = n;
} else {
MLD_PRINTF(("%s: copying 0x%llx\n", __func__,
(uint64_t)VM_KERNEL_ADDRPERM(m)));
m0 = m_dup(m, M_NOWAIT);
if (m0 == NULL) {
return ENOMEM;
}
m0->m_nextpkt = NULL;
m = m->m_nextpkt;
}
if (!domerge) {
MLD_PRINTF(("%s: queueing 0x%llx to ifscq 0x%llx)\n",
__func__, (uint64_t)VM_KERNEL_ADDRPERM(m0),
(uint64_t)VM_KERNEL_ADDRPERM(ifscq)));
IF_ENQUEUE(ifscq, m0);
} else {
struct mbuf *mtl; /* last mbuf of packet mt */
MLD_PRINTF(("%s: merging 0x%llx with ifscq tail "
"0x%llx)\n", __func__,
(uint64_t)VM_KERNEL_ADDRPERM(m0),
(uint64_t)VM_KERNEL_ADDRPERM(mt)));
mtl = m_last(mt);
m0->m_flags &= ~M_PKTHDR;
mt->m_pkthdr.len += recslen;
mt->m_pkthdr.vt_nrecs +=
m0->m_pkthdr.vt_nrecs;
mtl->m_next = m0;
}
}
return 0;
}
/*
* Respond to a pending MLDv2 General Query.
*/
static uint32_t
mld_v2_dispatch_general_query(struct mld_ifinfo *mli)
{
struct ifnet *ifp;
struct in6_multi *inm;
struct in6_multistep step;
int retval;
MLI_LOCK_ASSERT_HELD(mli);
VERIFY(mli->mli_version == MLD_VERSION_2);
ifp = mli->mli_ifp;
MLI_UNLOCK(mli);
in6_multihead_lock_shared();
IN6_FIRST_MULTI(step, inm);
while (inm != NULL) {
IN6M_LOCK(inm);
if (inm->in6m_ifp != ifp) {
goto next;
}
switch (inm->in6m_state) {
case MLD_NOT_MEMBER:
case MLD_SILENT_MEMBER:
break;
case MLD_REPORTING_MEMBER:
case MLD_IDLE_MEMBER:
case MLD_LAZY_MEMBER:
case MLD_SLEEPING_MEMBER:
case MLD_AWAKENING_MEMBER:
inm->in6m_state = MLD_REPORTING_MEMBER;
MLI_LOCK(mli);
retval = mld_v2_enqueue_group_record(&mli->mli_gq,
inm, 0, 0, 0, 0);
MLI_UNLOCK(mli);
MLD_PRINTF(("%s: enqueue record = %d\n",
__func__, retval));
break;
case MLD_G_QUERY_PENDING_MEMBER:
case MLD_SG_QUERY_PENDING_MEMBER:
case MLD_LEAVING_MEMBER:
break;
}
next:
IN6M_UNLOCK(inm);
IN6_NEXT_MULTI(step, inm);
}
in6_multihead_lock_done();
MLI_LOCK(mli);
mld_dispatch_queue_locked(mli, &mli->mli_gq, MLD_MAX_RESPONSE_BURST);
MLI_LOCK_ASSERT_HELD(mli);
/*
* Slew transmission of bursts over 1 second intervals.
*/
if (mli->mli_gq.ifq_head != NULL) {
mli->mli_v2_timer = 1 + MLD_RANDOM_DELAY(
MLD_RESPONSE_BURST_INTERVAL);
}
return mli->mli_v2_timer;
}
/*
* Transmit the next pending message in the output queue.
*
* Must not be called with in6m_lockm or mli_lock held.
*/
__attribute__((noinline))
static void
mld_dispatch_packet(struct mbuf *m)
{
struct ip6_moptions *im6o;
struct ifnet *ifp;
struct ifnet *__single oifp = NULL;
mbuf_ref_t m0, md;
struct ip6_hdr *ip6;
struct icmp6_hdr *icmp6;
int error;
int off;
int type;
MLD_PRINTF(("%s: transmit 0x%llx\n", __func__,
(uint64_t)VM_KERNEL_ADDRPERM(m)));
/*
* Check if the ifnet is still attached.
*/
ifp = mld_restore_context(m);
if (ifp == NULL || !ifnet_is_attached(ifp, 0)) {
os_log_error(OS_LOG_DEFAULT, "%s: dropped 0x%llx as interface went away\n",
__func__, (uint64_t)VM_KERNEL_ADDRPERM(m));
m_freem(m);
ip6stat.ip6s_noroute++;
return;
}
im6o = ip6_allocmoptions(Z_WAITOK);
if (im6o == NULL) {
m_freem(m);
return;
}
im6o->im6o_multicast_hlim = 1;
im6o->im6o_multicast_loop = 0;
im6o->im6o_multicast_ifp = ifp;
if (m->m_flags & M_MLDV1) {
m0 = m;
} else {
m0 = mld_v2_encap_report(ifp, m);
if (m0 == NULL) {
os_log_error(OS_LOG_DEFAULT, "%s: dropped 0x%llx\n", __func__,
(uint64_t)VM_KERNEL_ADDRPERM(m));
/*
* mld_v2_encap_report() has already freed our mbuf.
*/
IM6O_REMREF(im6o);
ip6stat.ip6s_odropped++;
return;
}
}
mld_scrub_context(m0);
m->m_flags &= ~(M_PROTOFLAGS);
m0->m_pkthdr.rcvif = lo_ifp;
ip6 = mtod(m0, struct ip6_hdr *);
(void)in6_setscope(&ip6->ip6_dst, ifp, NULL);
ip6_output_setdstifscope(m0, ifp->if_index, NULL);
/*
* Retrieve the ICMPv6 type before handoff to ip6_output(),
* so we can bump the stats.
*/
md = m_getptr(m0, sizeof(struct ip6_hdr), &off);
icmp6 = (struct icmp6_hdr *)(mtod(md, uint8_t *) + off);
type = icmp6->icmp6_type;
if (ifp->if_eflags & IFEF_TXSTART) {
/*
* Use control service class if the outgoing
* interface supports transmit-start model.
*/
(void) m_set_service_class(m0, MBUF_SC_CTL);
}
error = ip6_output(m0, &mld_po, NULL, IPV6_UNSPECSRC, im6o,
&oifp, NULL);
IM6O_REMREF(im6o);
if (error) {
os_log_error(OS_LOG_DEFAULT, "%s: ip6_output(0x%llx) = %d\n", __func__,
(uint64_t)VM_KERNEL_ADDRPERM(m0), error);
if (oifp != NULL) {
ifnet_release(oifp);
}
return;
}
icmp6stat.icp6s_outhist[type]++;
if (oifp != NULL) {
icmp6_ifstat_inc(oifp, ifs6_out_msg);
switch (type) {
case MLD_LISTENER_REPORT:
case MLDV2_LISTENER_REPORT:
icmp6_ifstat_inc(oifp, ifs6_out_mldreport);
break;
case MLD_LISTENER_DONE:
icmp6_ifstat_inc(oifp, ifs6_out_mlddone);
break;
}
ifnet_release(oifp);
}
}
/*
* Encapsulate an MLDv2 report.
*
* KAME IPv6 requires that hop-by-hop options be passed separately,
* and that the IPv6 header be prepended in a separate mbuf.
*
* Returns a pointer to the new mbuf chain head, or NULL if the
* allocation failed.
*/
static struct mbuf *
mld_v2_encap_report(struct ifnet *ifp, struct mbuf *m)
{
struct mbuf *mh;
struct mldv2_report *mld;
struct ip6_hdr *ip6;
struct in6_ifaddr *ia;
int mldreclen;
VERIFY(m->m_flags & M_PKTHDR);
/*
* RFC3590: OK to send as :: or tentative during DAD.
*/
ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY | IN6_IFF_ANYCAST);
if (ia == NULL) {
MLD_PRINTF(("%s: warning: ia is NULL\n", __func__));
}
MGETHDR(mh, M_DONTWAIT, MT_HEADER);
if (mh == NULL) {
if (ia != NULL) {
ifa_remref(&ia->ia_ifa);
}
m_freem(m);
return NULL;
}
MH_ALIGN(mh, sizeof(struct ip6_hdr) + sizeof(struct mldv2_report));
mldreclen = m_length(m);
MLD_PRINTF(("%s: mldreclen is %d\n", __func__, mldreclen));
mh->m_len = sizeof(struct ip6_hdr) + sizeof(struct mldv2_report);
mh->m_pkthdr.len = sizeof(struct ip6_hdr) +
sizeof(struct mldv2_report) + mldreclen;
ip6 = mtod(mh, struct ip6_hdr *);
ip6->ip6_flow = 0;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
ip6->ip6_nxt = IPPROTO_ICMPV6;
if (ia != NULL) {
IFA_LOCK(&ia->ia_ifa);
}
ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
ip6_output_setsrcifscope(mh, IFSCOPE_NONE, ia);
if (ia != NULL) {
IFA_UNLOCK(&ia->ia_ifa);
ifa_remref(&ia->ia_ifa);
ia = NULL;
}
ip6->ip6_dst = in6addr_linklocal_allv2routers;
ip6_output_setdstifscope(mh, ifp->if_index, NULL);
/* scope ID will be set in netisr */
mld = (struct mldv2_report *)(ip6 + 1);
mld->mld_type = MLDV2_LISTENER_REPORT;
mld->mld_code = 0;
mld->mld_cksum = 0;
mld->mld_v2_reserved = 0;
mld->mld_v2_numrecs = htons(m->m_pkthdr.vt_nrecs);
m->m_pkthdr.vt_nrecs = 0;
m->m_flags &= ~M_PKTHDR;
mh->m_next = m;
mld->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6,
sizeof(struct ip6_hdr), sizeof(struct mldv2_report) + mldreclen);
return mh;
}
#ifdef MLD_DEBUG
static const char *
mld_rec_type_to_str(const int type)
{
switch (type) {
case MLD_CHANGE_TO_EXCLUDE_MODE:
return "TO_EX";
case MLD_CHANGE_TO_INCLUDE_MODE:
return "TO_IN";
case MLD_MODE_IS_EXCLUDE:
return "MODE_EX";
case MLD_MODE_IS_INCLUDE:
return "MODE_IN";
case MLD_ALLOW_NEW_SOURCES:
return "ALLOW_NEW";
case MLD_BLOCK_OLD_SOURCES:
return "BLOCK_OLD";
default:
break;
}
return "unknown";
}
#endif
void
mld_init(void)
{
os_log(OS_LOG_DEFAULT, "%s: initializing\n", __func__);
ip6_initpktopts(&mld_po);
mld_po.ip6po_hlim = 1;
mld_po.ip6po_hbh = &mld_ra.hbh;
mld_po.ip6po_prefer_tempaddr = IP6PO_TEMPADDR_NOTPREFER;
mld_po.ip6po_flags = IP6PO_DONTFRAG;
LIST_INIT(&mli_head);
}