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06fa597aae
freebsd-skq/sys/netinet6/mld6.c
hselasky 312adcd942 Fix refcounting leaks in IPv6 MLD code leading to loss of IPv6 
connectivity.

Looking at past changes in this area like r337866, some refcounting
bugs have been introduced, one by one. For example like calling
in6m_disconnect() and in6m_rele_locked() in mld_v1_process_group_timer()
where previously no disconnect nor refcount decrement was done.
Calling in6m_disconnect() when it shouldn't causes IPv6 solitation to no
longer work, because all the multicast addresses receiving the solitation
messages are now deleted from the network interface.

This patch reverts some recent changes while improving the MLD
refcounting and concurrency model after the MLD code was converted
to using EPOCH(9).

List changes:
- All CK_STAILQ_FOREACH() macros are now properly enclosed into
  EPOCH(9) sections. This simplifies assertion of locking inside
  in6m_ifmultiaddr_get_inm().
- Corrected bad use of in6m_disconnect() leading to loss of IPv6
  connectivity for MLD v1.
- Factored out checks for valid inm structure into
  in6m_ifmultiaddr_get_inm().

PR:			233535
Differential Revision:	https://reviews.freebsd.org/D18887
Reviewed by:		bz (net)
Tested by:		ae
MFC after:		1 week
Sponsored by:		Mellanox Technologies
2019-01-24 08:34:13 +00:00

3339 lines
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/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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.
*
* $KAME: mld6.c,v 1.27 2001/04/04 05:17:30 itojun Exp $
*/
/*-
* 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. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)igmp.c 8.1 (Berkeley) 7/19/93
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.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/callout.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/ktr.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/route.h>
#include <net/vnet.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 <security/mac/mac_framework.h>
#ifndef KTR_MLD
#define KTR_MLD KTR_INET6
#endif
static struct mld_ifsoftc *
mli_alloc_locked(struct ifnet *);
static void mli_delete_locked(const struct ifnet *);
static void mld_dispatch_packet(struct mbuf *);
static void mld_dispatch_queue(struct mbufq *, int);
static void mld_final_leave(struct in6_multi *, struct mld_ifsoftc *);
static void mld_fasttimo_vnet(struct in6_multi_head *inmh);
static int mld_handle_state_change(struct in6_multi *,
struct mld_ifsoftc *);
static int mld_initial_join(struct in6_multi *, struct mld_ifsoftc *,
const int);
#ifdef KTR
static char * mld_rec_type_to_str(const int);
#endif
static void mld_set_version(struct mld_ifsoftc *, const int);
static void mld_slowtimo_vnet(void);
static int mld_v1_input_query(struct ifnet *, const struct ip6_hdr *,
/*const*/ struct mld_hdr *);
static int mld_v1_input_report(struct ifnet *, const struct ip6_hdr *,
/*const*/ struct mld_hdr *);
static void mld_v1_process_group_timer(struct in6_multi_head *,
struct in6_multi *);
static void mld_v1_process_querier_timers(struct mld_ifsoftc *);
static int mld_v1_transmit_report(struct in6_multi *, const int);
static void mld_v1_update_group(struct in6_multi *, const int);
static void mld_v2_cancel_link_timers(struct mld_ifsoftc *);
static void mld_v2_dispatch_general_query(struct mld_ifsoftc *);
static struct mbuf *
mld_v2_encap_report(struct ifnet *, struct mbuf *);
static int mld_v2_enqueue_filter_change(struct mbufq *,
struct in6_multi *);
static int mld_v2_enqueue_group_record(struct mbufq *,
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 mbufq *);
static void mld_v2_process_group_timers(struct in6_multi_head *,
struct mbufq *, struct mbufq *,
struct in6_multi *, const int);
static int mld_v2_process_group_query(struct in6_multi *,
struct mld_ifsoftc *mli, int, struct mbuf *, const int);
static int sysctl_mld_gsr(SYSCTL_HANDLER_ARGS);
static int sysctl_mld_ifinfo(SYSCTL_HANDLER_ARGS);
/*
* Normative references: RFC 2710, RFC 3590, RFC 3810.
*
* Locking:
* * The MLD subsystem lock ends up being system-wide for the moment,
* but could be per-VIMAGE later on.
* * The permitted lock order is: IN6_MULTI_LOCK, MLD_LOCK, IF_ADDR_LOCK.
* Any may be taken independently; if any are held at the same
* time, the above lock order must be followed.
* * IN6_MULTI_LOCK covers in_multi.
* * MLD_LOCK covers per-link state and any global variables in this file.
* * IF_ADDR_LOCK covers if_multiaddrs, which is used for a variety of
* per-link state iterators.
*
* XXX LOR PREVENTION
* A special case for IPv6 is the in6_setscope() routine. ip6_output()
* will not accept an ifp; it wants an embedded scope ID, unlike
* ip_output(), which happily takes the ifp given to it. The embedded
* scope ID is only used by MLD to select the outgoing interface.
*
* During interface attach and detach, MLD will take MLD_LOCK *after*
* the IF_AFDATA_LOCK.
* As in6_setscope() takes IF_AFDATA_LOCK then SCOPE_LOCK, we can't call
* it with MLD_LOCK held without triggering an LOR. A netisr with indirect
* dispatch could work around this, but we'd rather not do that, as it
* can introduce other races.
*
* As such, we exploit the fact that the scope ID is just the interface
* index, and embed it in the IPv6 destination address accordingly.
* This is potentially NOT VALID for MLDv1 reports, as they
* are always sent to the multicast group itself; as MLDv2
* reports are always sent to ff02::16, this is not an issue
* when MLDv2 is in use.
*
* This does not however eliminate the LOR when ip6_output() itself
* calls in6_setscope() internally whilst MLD_LOCK is held. This will
* trigger a LOR warning in WITNESS when the ifnet is detached.
*
* The right answer is probably to make IF_AFDATA_LOCK an rwlock, given
* how it's used across the network stack. Here we're simply exploiting
* the fact that MLD runs at a similar layer in the stack to scope6.c.
*
* VIMAGE:
* * Each in6_multi corresponds to an ifp, and each ifp corresponds
* to a vnet in ifp->if_vnet.
*/
static struct mtx mld_mtx;
static MALLOC_DEFINE(M_MLD, "mld", "mld state");
#define MLD_EMBEDSCOPE(pin6, zoneid) \
if (IN6_IS_SCOPE_LINKLOCAL(pin6) || \
IN6_IS_ADDR_MC_INTFACELOCAL(pin6)) \
(pin6)->s6_addr16[1] = htons((zoneid) & 0xFFFF) \
/*
* VIMAGE-wide globals.
*/
VNET_DEFINE_STATIC(struct timeval, mld_gsrdelay) = {10, 0};
VNET_DEFINE_STATIC(LIST_HEAD(, mld_ifsoftc), mli_head);
VNET_DEFINE_STATIC(int, interface_timers_running6);
VNET_DEFINE_STATIC(int, state_change_timers_running6);
VNET_DEFINE_STATIC(int, current_state_timers_running6);
#define V_mld_gsrdelay VNET(mld_gsrdelay)
#define V_mli_head VNET(mli_head)
#define V_interface_timers_running6 VNET(interface_timers_running6)
#define V_state_change_timers_running6 VNET(state_change_timers_running6)
#define V_current_state_timers_running6 VNET(current_state_timers_running6)
SYSCTL_DECL(_net_inet6); /* Note: Not in any common header. */
SYSCTL_NODE(_net_inet6, OID_AUTO, mld, CTLFLAG_RW, 0,
"IPv6 Multicast Listener Discovery");
/*
* Virtualized sysctls.
*/
SYSCTL_PROC(_net_inet6_mld, OID_AUTO, gsrdelay,
CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
&VNET_NAME(mld_gsrdelay.tv_sec), 0, sysctl_mld_gsr, "I",
"Rate limit for MLDv2 Group-and-Source queries in seconds");
/*
* Non-virtualized sysctls.
*/
static SYSCTL_NODE(_net_inet6_mld, OID_AUTO, ifinfo,
CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_mld_ifinfo,
"Per-interface MLDv2 state");
static int mld_v1enable = 1;
SYSCTL_INT(_net_inet6_mld, OID_AUTO, v1enable, CTLFLAG_RWTUN,
&mld_v1enable, 0, "Enable fallback to MLDv1");
static int mld_v2enable = 1;
SYSCTL_INT(_net_inet6_mld, OID_AUTO, v2enable, CTLFLAG_RWTUN,
&mld_v2enable, 0, "Enable MLDv2");
static int mld_use_allow = 1;
SYSCTL_INT(_net_inet6_mld, OID_AUTO, use_allow, CTLFLAG_RWTUN,
&mld_use_allow, 0, "Use ALLOW/BLOCK for RFC 4604 SSM joins/leaves");
/*
* 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 = { 0, 0 },
.pad = { .ip6o_type = IP6OPT_PADN, 0 },
.ra = {
.ip6or_type = IP6OPT_ROUTER_ALERT,
.ip6or_len = IP6OPT_RTALERT_LEN - 2,
.ip6or_value[0] = ((IP6OPT_RTALERT_MLD >> 8) & 0xFF),
.ip6or_value[1] = (IP6OPT_RTALERT_MLD & 0xFF)
}
};
static struct ip6_pktopts mld_po;
static __inline void
mld_save_context(struct mbuf *m, struct ifnet *ifp)
{
#ifdef VIMAGE
m->m_pkthdr.PH_loc.ptr = ifp->if_vnet;
#endif /* VIMAGE */
m->m_pkthdr.flowid = ifp->if_index;
}
static __inline void
mld_scrub_context(struct mbuf *m)
{
m->m_pkthdr.PH_loc.ptr = NULL;
m->m_pkthdr.flowid = 0;
}
/*
* Restore context from a queued output chain.
* Return saved ifindex.
*
* VIMAGE: The assertion is there to make sure that we
* actually called CURVNET_SET() with what's in the mbuf chain.
*/
static __inline uint32_t
mld_restore_context(struct mbuf *m)
{
#if defined(VIMAGE) && defined(INVARIANTS)
KASSERT(curvnet == m->m_pkthdr.PH_loc.ptr,
("%s: called when curvnet was not restored: cuvnet %p m ptr %p",
__func__, curvnet, m->m_pkthdr.PH_loc.ptr));
#endif
return (m->m_pkthdr.flowid);
}
/*
* Retrieve or set threshold between group-source queries in seconds.
*
* VIMAGE: Assume curvnet set by caller.
* SMPng: NOTE: Serialized by MLD lock.
*/
static int
sysctl_mld_gsr(SYSCTL_HANDLER_ARGS)
{
int error;
int i;
error = sysctl_wire_old_buffer(req, sizeof(int));
if (error)
return (error);
MLD_LOCK();
i = V_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;
}
CTR2(KTR_MLD, "change mld_gsrdelay from %d to %d",
V_mld_gsrdelay.tv_sec, i);
V_mld_gsrdelay.tv_sec = i;
out_locked:
MLD_UNLOCK();
return (error);
}
/*
* Expose struct mld_ifsoftc to userland, keyed by ifindex.
* For use by ifmcstat(8).
*
* SMPng: NOTE: Does an unlocked ifindex space read.
* VIMAGE: Assume curvnet set by caller. The node handler itself
* is not directly virtualized.
*/
static int
sysctl_mld_ifinfo(SYSCTL_HANDLER_ARGS)
{
int *name;
int error;
u_int namelen;
struct ifnet *ifp;
struct mld_ifsoftc *mli;
name = (int *)arg1;
namelen = arg2;
if (req->newptr != NULL)
return (EPERM);
if (namelen != 1)
return (EINVAL);
error = sysctl_wire_old_buffer(req, sizeof(struct mld_ifinfo));
if (error)
return (error);
IN6_MULTI_LOCK();
IN6_MULTI_LIST_LOCK();
MLD_LOCK();
if (name[0] <= 0 || name[0] > V_if_index) {
error = ENOENT;
goto out_locked;
}
error = ENOENT;
ifp = ifnet_byindex(name[0]);
if (ifp == NULL)
goto out_locked;
LIST_FOREACH(mli, &V_mli_head, mli_link) {
if (ifp == mli->mli_ifp) {
struct mld_ifinfo info;
info.mli_version = mli->mli_version;
info.mli_v1_timer = mli->mli_v1_timer;
info.mli_v2_timer = mli->mli_v2_timer;
info.mli_flags = mli->mli_flags;
info.mli_rv = mli->mli_rv;
info.mli_qi = mli->mli_qi;
info.mli_qri = mli->mli_qri;
info.mli_uri = mli->mli_uri;
error = SYSCTL_OUT(req, &info, sizeof(info));
break;
}
}
out_locked:
MLD_UNLOCK();
IN6_MULTI_LIST_UNLOCK();
IN6_MULTI_UNLOCK();
return (error);
}
/*
* Dispatch an entire queue of pending packet chains.
* VIMAGE: Assumes the vnet pointer has been set.
*/
static void
mld_dispatch_queue(struct mbufq *mq, int limit)
{
struct mbuf *m;
while ((m = mbufq_dequeue(mq)) != NULL) {
CTR3(KTR_MLD, "%s: dispatch %p from %p", __func__, mq, m);
mld_dispatch_packet(m);
if (--limit == 0)
break;
}
}
/*
* 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)
{
KASSERT(IN6_IS_ADDR_MULTICAST(addr), ("%s: not multicast", __func__));
if (IPV6_ADDR_MC_SCOPE(addr) == IPV6_ADDR_SCOPE_NODELOCAL)
return (0);
if (IPV6_ADDR_MC_SCOPE(addr) == IPV6_ADDR_SCOPE_LINKLOCAL) {
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.
*
* SMPng: Normally called with IF_AFDATA_LOCK held.
*/
struct mld_ifsoftc *
mld_domifattach(struct ifnet *ifp)
{
struct mld_ifsoftc *mli;
CTR3(KTR_MLD, "%s: called for ifp %p(%s)",
__func__, ifp, if_name(ifp));
MLD_LOCK();
mli = mli_alloc_locked(ifp);
if (!(ifp->if_flags & IFF_MULTICAST))
mli->mli_flags |= MLIF_SILENT;
if (mld_use_allow)
mli->mli_flags |= MLIF_USEALLOW;
MLD_UNLOCK();
return (mli);
}
/*
* VIMAGE: assume curvnet set by caller.
*/
static struct mld_ifsoftc *
mli_alloc_locked(/*const*/ struct ifnet *ifp)
{
struct mld_ifsoftc *mli;
MLD_LOCK_ASSERT();
mli = malloc(sizeof(struct mld_ifsoftc), M_MLD, M_NOWAIT|M_ZERO);
if (mli == NULL)
goto out;
mli->mli_ifp = ifp;
mli->mli_version = MLD_VERSION_2;
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;
mbufq_init(&mli->mli_gq, MLD_MAX_RESPONSE_PACKETS);
LIST_INSERT_HEAD(&V_mli_head, mli, mli_link);
CTR2(KTR_MLD, "allocate mld_ifsoftc for ifp %p(%s)",
ifp, if_name(ifp));
out:
return (mli);
}
/*
* Hook for ifdetach.
*
* NOTE: Some finalization tasks need to run before the protocol domain
* is detached, but also before the link layer does its cleanup.
* Run before link-layer cleanup; cleanup groups, but do not free MLD state.
*
* SMPng: Caller must hold IN6_MULTI_LOCK().
* Must take IF_ADDR_LOCK() to cover if_multiaddrs iterator.
* XXX This routine is also bitten by unlocked ifma_protospec access.
*/
void
mld_ifdetach(struct ifnet *ifp, struct in6_multi_head *inmh)
{
struct epoch_tracker et;
struct mld_ifsoftc *mli;
struct ifmultiaddr *ifma;
struct in6_multi *inm;
CTR3(KTR_MLD, "%s: called for ifp %p(%s)", __func__, ifp,
if_name(ifp));
IN6_MULTI_LIST_LOCK_ASSERT();
MLD_LOCK();
mli = MLD_IFINFO(ifp);
IF_ADDR_WLOCK(ifp);
/*
* Extract list of in6_multi associated with the detaching ifp
* which the PF_INET6 layer is about to release.
*/
NET_EPOCH_ENTER(et);
CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
inm = in6m_ifmultiaddr_get_inm(ifma);
if (inm == NULL)
continue;
in6m_disconnect_locked(inmh, inm);
if (mli->mli_version == MLD_VERSION_2) {
in6m_clear_recorded(inm);
/*
* We need to release the final reference held
* for issuing the INCLUDE {}.
*/
if (inm->in6m_state == MLD_LEAVING_MEMBER) {
inm->in6m_state = MLD_NOT_MEMBER;
in6m_rele_locked(inmh, inm);
}
}
}
NET_EPOCH_EXIT(et);
IF_ADDR_WUNLOCK(ifp);
MLD_UNLOCK();
}
/*
* Hook for domifdetach.
* Runs after link-layer cleanup; free MLD state.
*
* SMPng: Normally called with IF_AFDATA_LOCK held.
*/
void
mld_domifdetach(struct ifnet *ifp)
{
CTR3(KTR_MLD, "%s: called for ifp %p(%s)",
__func__, ifp, if_name(ifp));
MLD_LOCK();
mli_delete_locked(ifp);
MLD_UNLOCK();
}
static void
mli_delete_locked(const struct ifnet *ifp)
{
struct mld_ifsoftc *mli, *tmli;
CTR3(KTR_MLD, "%s: freeing mld_ifsoftc for ifp %p(%s)",
__func__, ifp, if_name(ifp));
MLD_LOCK_ASSERT();
LIST_FOREACH_SAFE(mli, &V_mli_head, mli_link, tmli) {
if (mli->mli_ifp == ifp) {
/*
* Free deferred General Query responses.
*/
mbufq_drain(&mli->mli_gq);
LIST_REMOVE(mli, mli_link);
free(mli, M_MLD);
return;
}
}
}
/*
* 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 epoch_tracker et;
struct ifmultiaddr *ifma;
struct mld_ifsoftc *mli;
struct in6_multi *inm;
int is_general_query;
uint16_t timer;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
is_general_query = 0;
if (!mld_v1enable) {
CTR3(KTR_MLD, "ignore v1 query %s on ifp %p(%s)",
ip6_sprintf(ip6tbuf, &mld->mld_addr),
ifp, if_name(ifp));
return (0);
}
/*
* RFC3810 Section 6.2: MLD queries must originate from
* a router's link-local address.
*/
if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)",
ip6_sprintf(ip6tbuf, &ip6->ip6_src),
ifp, if_name(ifp));
return (0);
}
/*
* 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))
return (EINVAL);
is_general_query = 1;
} else {
/*
* Embed scope ID of receiving interface in MLD query for
* lookup whilst we don't hold other locks.
*/
in6_setscope(&mld->mld_addr, ifp, NULL);
}
IN6_MULTI_LIST_LOCK();
MLD_LOCK();
/*
* Switch to MLDv1 host compatibility mode.
*/
mli = MLD_IFINFO(ifp);
KASSERT(mli != NULL, ("%s: no mld_ifsoftc for ifp %p", __func__, ifp));
mld_set_version(mli, MLD_VERSION_1);
timer = (ntohs(mld->mld_maxdelay) * PR_FASTHZ) / MLD_TIMER_SCALE;
if (timer == 0)
timer = 1;
NET_EPOCH_ENTER(et);
if (is_general_query) {
/*
* For each reporting group joined on this
* interface, kick the report timer.
*/
CTR2(KTR_MLD, "process v1 general query on ifp %p(%s)",
ifp, if_name(ifp));
CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
inm = in6m_ifmultiaddr_get_inm(ifma);
if (inm == NULL)
continue;
mld_v1_update_group(inm, timer);
}
} else {
/*
* MLDv1 Group-Specific Query.
* If this is a group-specific MLDv1 query, we need only
* look up the single group to process it.
*/
inm = in6m_lookup_locked(ifp, &mld->mld_addr);
if (inm != NULL) {
CTR3(KTR_MLD, "process v1 query %s on ifp %p(%s)",
ip6_sprintf(ip6tbuf, &mld->mld_addr),
ifp, if_name(ifp));
mld_v1_update_group(inm, timer);
}
/* XXX Clear embedded scope ID as userland won't expect it. */
in6_clearscope(&mld->mld_addr);
}
NET_EPOCH_EXIT(et);
MLD_UNLOCK();
IN6_MULTI_LIST_UNLOCK();
return (0);
}
/*
* 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 void
mld_v1_update_group(struct in6_multi *inm, const int timer)
{
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
CTR4(KTR_MLD, "%s: %s/%s timer=%d", __func__,
ip6_sprintf(ip6tbuf, &inm->in6m_addr),
if_name(inm->in6m_ifp), timer);
IN6_MULTI_LIST_LOCK_ASSERT();
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) {
CTR1(KTR_MLD, "%s: REPORTING and timer running, "
"skipping.", __func__);
break;
}
/* 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:
CTR1(KTR_MLD, "%s: ->REPORTING", __func__);
inm->in6m_state = MLD_REPORTING_MEMBER;
inm->in6m_timer = MLD_RANDOM_DELAY(timer);
V_current_state_timers_running6 = 1;
break;
case MLD_SLEEPING_MEMBER:
CTR1(KTR_MLD, "%s: ->AWAKENING", __func__);
inm->in6m_state = MLD_AWAKENING_MEMBER;
break;
case MLD_LEAVING_MEMBER:
break;
}
}
/*
* 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_ifsoftc *mli;
struct mldv2_query *mld;
struct in6_multi *inm;
uint32_t maxdelay, nsrc, qqi;
int is_general_query;
uint16_t timer;
uint8_t qrv;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
if (!mld_v2enable) {
CTR3(KTR_MLD, "ignore v2 query src %s on ifp %p(%s)",
ip6_sprintf(ip6tbuf, &ip6->ip6_src),
ifp, if_name(ifp));
return (0);
}
/*
* RFC3810 Section 6.2: MLD queries must originate from
* a router's link-local address.
*/
if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)",
ip6_sprintf(ip6tbuf, &ip6->ip6_src),
ifp, if_name(ifp));
return (0);
}
is_general_query = 0;
CTR2(KTR_MLD, "input v2 query on ifp %p(%s)", ifp, 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 >= 32768) {
maxdelay = (MLD_MRC_MANT(maxdelay) | 0x1000) <<
(MLD_MRC_EXP(maxdelay) + 3);
}
timer = (maxdelay * PR_FASTHZ) / MLD_TIMER_SCALE;
if (timer == 0)
timer = 1;
qrv = MLD_QRV(mld->mld_misc);
if (qrv < 2) {
CTR3(KTR_MLD, "%s: clamping qrv %d to %d", __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)
return (EMSGSIZE);
if (icmp6len < sizeof(struct mldv2_query) +
(nsrc * sizeof(struct in6_addr)))
return (EMSGSIZE);
/*
* 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)
return (EINVAL);
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.
*/
in6_setscope(&mld->mld_addr, ifp, NULL);
}
IN6_MULTI_LIST_LOCK();
MLD_LOCK();
mli = MLD_IFINFO(ifp);
KASSERT(mli != NULL, ("%s: no mld_ifsoftc for ifp %p", __func__, ifp));
/*
* 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)
goto out_locked;
mld_set_version(mli, MLD_VERSION_2);
mli->mli_rv = qrv;
mli->mli_qi = qqi;
mli->mli_qri = maxdelay;
CTR4(KTR_MLD, "%s: qrv %d qi %d maxdelay %d", __func__, qrv, qqi,
maxdelay);
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.
*/
CTR2(KTR_MLD, "process v2 general query on ifp %p(%s)",
ifp, if_name(ifp));
if (mli->mli_v2_timer == 0 || mli->mli_v2_timer >= timer) {
mli->mli_v2_timer = MLD_RANDOM_DELAY(timer);
V_interface_timers_running6 = 1;
}
} else {
struct epoch_tracker et;
/*
* 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.
*/
NET_EPOCH_ENTER(et);
inm = in6m_lookup_locked(ifp, &mld->mld_addr);
if (inm == NULL) {
NET_EPOCH_EXIT(et);
goto out_locked;
}
if (nsrc > 0) {
if (!ratecheck(&inm->in6m_lastgsrtv,
&V_mld_gsrdelay)) {
CTR1(KTR_MLD, "%s: GS query throttled.",
__func__);
NET_EPOCH_EXIT(et);
goto out_locked;
}
}
CTR2(KTR_MLD, "process v2 group query on ifp %p(%s)",
ifp, 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.
*/
if (mli->mli_v2_timer == 0 || mli->mli_v2_timer >= timer)
mld_v2_process_group_query(inm, mli, timer, m, off);
/* XXX Clear embedded scope ID as userland won't expect it. */
in6_clearscope(&mld->mld_addr);
NET_EPOCH_EXIT(et);
}
out_locked:
MLD_UNLOCK();
IN6_MULTI_LIST_UNLOCK();
return (0);
}
/*
* Process a received MLDv2 group-specific or group-and-source-specific
* query.
* Return <0 if any error occurred. Currently this is ignored.
*/
static int
mld_v2_process_group_query(struct in6_multi *inm, struct mld_ifsoftc *mli,
int timer, struct mbuf *m0, const int off)
{
struct mldv2_query *mld;
int retval;
uint16_t nsrc;
IN6_MULTI_LIST_LOCK_ASSERT();
MLD_LOCK_ASSERT();
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);
break;
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);
V_current_state_timers_running6 = 1;
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);
V_current_state_timers_running6 = 1;
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;
uint8_t *sp;
int i, nrecorded;
int soff;
m = m0;
soff = off + sizeof(struct mldv2_query);
nrecorded = 0;
for (i = 0; i < nsrc; i++) {
sp = mtod(m, uint8_t *) + soff;
retval = in6m_record_source(inm,
(const struct in6_addr *)sp);
if (retval < 0)
break;
nrecorded += retval;
soff += sizeof(struct in6_addr);
if (soff >= m->m_len) {
soff = soff - m->m_len;
m = m->m_next;
if (m == NULL)
break;
}
}
if (nrecorded > 0) {
CTR1(KTR_MLD,
"%s: schedule response to SG query", __func__);
inm->in6m_state = MLD_SG_QUERY_PENDING_MEMBER;
inm->in6m_timer = MLD_RANDOM_DELAY(timer);
V_current_state_timers_running6 = 1;
}
}
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, const struct ip6_hdr *ip6,
/*const*/ struct mld_hdr *mld)
{
struct in6_addr src, dst;
struct epoch_tracker et;
struct in6_ifaddr *ia;
struct in6_multi *inm;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
if (!mld_v1enable) {
CTR3(KTR_MLD, "ignore v1 report %s on ifp %p(%s)",
ip6_sprintf(ip6tbuf, &mld->mld_addr),
ifp, if_name(ifp));
return (0);
}
if (ifp->if_flags & IFF_LOOPBACK)
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)) {
CTR3(KTR_MLD, "ignore v1 query src %s on ifp %p(%s)",
ip6_sprintf(ip6tbuf, &ip6->ip6_src),
ifp, 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)) {
CTR3(KTR_MLD, "ignore v1 query dst %s on ifp %p(%s)",
ip6_sprintf(ip6tbuf, &ip6->ip6_dst),
ifp, 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 && IN6_ARE_ADDR_EQUAL(&ip6->ip6_src, IA6_IN6(ia))) ||
(ia == NULL && IN6_IS_ADDR_UNSPECIFIED(&src))) {
if (ia != NULL)
ifa_free(&ia->ia_ifa);
return (0);
}
if (ia != NULL)
ifa_free(&ia->ia_ifa);
CTR3(KTR_MLD, "process v1 report %s on ifp %p(%s)",
ip6_sprintf(ip6tbuf, &mld->mld_addr), ifp, 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))
in6_setscope(&mld->mld_addr, ifp, NULL);
IN6_MULTI_LIST_LOCK();
MLD_LOCK();
NET_EPOCH_ENTER(et);
/*
* 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.
*/
inm = in6m_lookup_locked(ifp, &mld->mld_addr);
if (inm != NULL) {
struct mld_ifsoftc *mli;
mli = inm->in6m_mli;
KASSERT(mli != NULL,
("%s: no mli for ifp %p", __func__, ifp));
/*
* 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)
goto out_locked;
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:
CTR3(KTR_MLD,
"report suppressed for %s on ifp %p(%s)",
ip6_sprintf(ip6tbuf, &mld->mld_addr),
ifp, if_name(ifp));
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;
}
}
out_locked:
NET_EPOCH_EXIT(et);
MLD_UNLOCK();
IN6_MULTI_LIST_UNLOCK();
/* 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;
struct ip6_hdr *ip6;
struct mld_hdr *mld;
int mldlen;
CTR3(KTR_MLD, "%s: called w/mbuf (%p,%d)", __func__, m, off);
ifp = m->m_pkthdr.rcvif;
ip6 = mtod(m, struct ip6_hdr *);
/* 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);
}
IP6_EXTHDR_GET(mld, struct mld_hdr *, m, off, mldlen);
if (mld == NULL) {
ICMP6STAT_INC(icp6s_badlen);
return (IPPROTO_DONE);
}
/*
* 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, 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);
}
/*
* Fast timeout handler (global).
* VIMAGE: Timeout handlers are expected to service all vimages.
*/
void
mld_fasttimo(void)
{
struct in6_multi_head inmh;
VNET_ITERATOR_DECL(vnet_iter);
SLIST_INIT(&inmh);
VNET_LIST_RLOCK_NOSLEEP();
VNET_FOREACH(vnet_iter) {
CURVNET_SET(vnet_iter);
mld_fasttimo_vnet(&inmh);
CURVNET_RESTORE();
}
VNET_LIST_RUNLOCK_NOSLEEP();
in6m_release_list_deferred(&inmh);
}
/*
* Fast timeout handler (per-vnet).
*
* VIMAGE: Assume caller has set up our curvnet.
*/
static void
mld_fasttimo_vnet(struct in6_multi_head *inmh)
{
struct epoch_tracker et;
struct mbufq scq; /* State-change packets */
struct mbufq qrq; /* Query response packets */
struct ifnet *ifp;
struct mld_ifsoftc *mli;
struct ifmultiaddr *ifma;
struct in6_multi *inm;
int uri_fasthz;
uri_fasthz = 0;
/*
* Quick check to see if any work needs to be done, in order to
* minimize the overhead of fasttimo processing.
* SMPng: XXX Unlocked reads.
*/
if (!V_current_state_timers_running6 &&
!V_interface_timers_running6 &&
!V_state_change_timers_running6)
return;
IN6_MULTI_LIST_LOCK();
MLD_LOCK();
/*
* MLDv2 General Query response timer processing.
*/
if (V_interface_timers_running6) {
CTR1(KTR_MLD, "%s: interface timers running", __func__);
V_interface_timers_running6 = 0;
LIST_FOREACH(mli, &V_mli_head, mli_link) {
if (mli->mli_v2_timer == 0) {
/* Do nothing. */
} else if (--mli->mli_v2_timer == 0) {
mld_v2_dispatch_general_query(mli);
} else {
V_interface_timers_running6 = 1;
}
}
}
if (!V_current_state_timers_running6 &&
!V_state_change_timers_running6)
goto out_locked;
V_current_state_timers_running6 = 0;
V_state_change_timers_running6 = 0;
CTR1(KTR_MLD, "%s: state change timers running", __func__);
/*
* MLD host report and state-change timer processing.
* Note: Processing a v2 group timer may remove a node.
*/
LIST_FOREACH(mli, &V_mli_head, mli_link) {
ifp = mli->mli_ifp;
if (mli->mli_version == MLD_VERSION_2) {
uri_fasthz = MLD_RANDOM_DELAY(mli->mli_uri *
PR_FASTHZ);
mbufq_init(&qrq, MLD_MAX_G_GS_PACKETS);
mbufq_init(&scq, MLD_MAX_STATE_CHANGE_PACKETS);
}
IF_ADDR_WLOCK(ifp);
NET_EPOCH_ENTER(et);
CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
inm = in6m_ifmultiaddr_get_inm(ifma);
if (inm == NULL)
continue;
switch (mli->mli_version) {
case MLD_VERSION_1:
mld_v1_process_group_timer(inmh, inm);
break;
case MLD_VERSION_2:
mld_v2_process_group_timers(inmh, &qrq,
&scq, inm, uri_fasthz);
break;
}
}
IF_ADDR_WUNLOCK(ifp);
switch (mli->mli_version) {
case MLD_VERSION_1:
/*
* Transmit reports for this lifecycle. This
* is done while not holding IF_ADDR_LOCK
* since this can call
* in6ifa_ifpforlinklocal() which locks
* IF_ADDR_LOCK internally as well as
* ip6_output() to transmit a packet.
*/
while ((inm = SLIST_FIRST(inmh)) != NULL) {
SLIST_REMOVE_HEAD(inmh, in6m_defer);
(void)mld_v1_transmit_report(inm,
MLD_LISTENER_REPORT);
}
break;
case MLD_VERSION_2:
mld_dispatch_queue(&qrq, 0);
mld_dispatch_queue(&scq, 0);
break;
}
NET_EPOCH_EXIT(et);
}
out_locked:
MLD_UNLOCK();
IN6_MULTI_LIST_UNLOCK();
}
/*
* Update host report group timer.
* Will update the global pending timer flags.
*/
static void
mld_v1_process_group_timer(struct in6_multi_head *inmh, struct in6_multi *inm)
{
int report_timer_expired;
IN6_MULTI_LIST_LOCK_ASSERT();
MLD_LOCK_ASSERT();
if (inm->in6m_timer == 0) {
report_timer_expired = 0;
} else if (--inm->in6m_timer == 0) {
report_timer_expired = 1;
} else {
V_current_state_timers_running6 = 1;
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;
SLIST_INSERT_HEAD(inmh, inm, in6m_defer);
}
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 in6_multi_head *inmh,
struct mbufq *qrq, struct mbufq *scq,
struct in6_multi *inm, const int uri_fasthz)
{
int query_response_timer_expired;
int state_change_retransmit_timer_expired;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
IN6_MULTI_LIST_LOCK_ASSERT();
MLD_LOCK_ASSERT();
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 slow-timeout path.
*/
if (inm->in6m_timer == 0) {
query_response_timer_expired = 0;
} else if (--inm->in6m_timer == 0) {
query_response_timer_expired = 1;
} else {
V_current_state_timers_running6 = 1;
}
if (inm->in6m_sctimer == 0) {
state_change_retransmit_timer_expired = 0;
} else if (--inm->in6m_sctimer == 0) {
state_change_retransmit_timer_expired = 1;
} else {
V_state_change_timers_running6 = 1;
}
/* We are in fasttimo, 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);
CTR2(KTR_MLD, "%s: enqueue record = %d",
__func__, retval);
inm->in6m_state = MLD_REPORTING_MEMBER;
in6m_clear_recorded(inm);
}
/* 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 = uri_fasthz;
V_state_change_timers_running6 = 1;
}
/*
* 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);
CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
ip6_sprintf(ip6tbuf, &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;
in6m_disconnect_locked(inmh, inm);
in6m_rele_locked(inmh, inm);
}
}
break;
}
}
/*
* Switch to a different version on the given interface,
* as per Section 9.12.
*/
static void
mld_set_version(struct mld_ifsoftc *mli, const int version)
{
int old_version_timer;
MLD_LOCK_ASSERT();
CTR4(KTR_MLD, "%s: switching to v%d on ifp %p(%s)", __func__,
version, mli->mli_ifp, if_name(mli->mli_ifp));
if (version == MLD_VERSION_1) {
/*
* Compute the "Older Version Querier Present" timer as per
* Section 9.12.
*/
old_version_timer = (mli->mli_rv * mli->mli_qi) + mli->mli_qri;
old_version_timer *= PR_SLOWHZ;
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);
}
}
/*
* Cancel pending MLDv2 timers for the given link and all groups
* joined on it; state-change, general-query, and group-query timers.
*/
static void
mld_v2_cancel_link_timers(struct mld_ifsoftc *mli)
{
struct epoch_tracker et;
struct in6_multi_head inmh;
struct ifmultiaddr *ifma;
struct ifnet *ifp;
struct in6_multi *inm;
CTR3(KTR_MLD, "%s: cancel v2 timers on ifp %p(%s)", __func__,
mli->mli_ifp, if_name(mli->mli_ifp));
SLIST_INIT(&inmh);
IN6_MULTI_LIST_LOCK_ASSERT();
MLD_LOCK_ASSERT();
/*
* Fast-track this potentially expensive operation
* by checking all the global 'timer pending' flags.
*/
if (!V_interface_timers_running6 &&
!V_state_change_timers_running6 &&
!V_current_state_timers_running6)
return;
mli->mli_v2_timer = 0;
ifp = mli->mli_ifp;
IF_ADDR_WLOCK(ifp);
NET_EPOCH_ENTER(et);
CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
inm = in6m_ifmultiaddr_get_inm(ifma);
if (inm == NULL)
continue;
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_LEAVING_MEMBER:
/*
* If we are leaving the group and switching
* version, we need to release the final
* reference held for issuing the INCLUDE {}.
*/
in6m_rele_locked(&inmh, inm);
/* FALLTHROUGH */
case MLD_G_QUERY_PENDING_MEMBER:
case MLD_SG_QUERY_PENDING_MEMBER:
in6m_clear_recorded(inm);
/* FALLTHROUGH */
case MLD_REPORTING_MEMBER:
inm->in6m_sctimer = 0;
inm->in6m_timer = 0;
inm->in6m_state = MLD_REPORTING_MEMBER;
/*
* Free any pending MLDv2 state-change records.
*/
mbufq_drain(&inm->in6m_scq);
break;
}
}
NET_EPOCH_EXIT(et);
IF_ADDR_WUNLOCK(ifp);
in6m_release_list_deferred(&inmh);
}
/*
* Global slowtimo handler.
* VIMAGE: Timeout handlers are expected to service all vimages.
*/
void
mld_slowtimo(void)
{
VNET_ITERATOR_DECL(vnet_iter);
VNET_LIST_RLOCK_NOSLEEP();
VNET_FOREACH(vnet_iter) {
CURVNET_SET(vnet_iter);
mld_slowtimo_vnet();
CURVNET_RESTORE();
}
VNET_LIST_RUNLOCK_NOSLEEP();
}
/*
* Per-vnet slowtimo handler.
*/
static void
mld_slowtimo_vnet(void)
{
struct mld_ifsoftc *mli;
MLD_LOCK();
LIST_FOREACH(mli, &V_mli_head, mli_link) {
mld_v1_process_querier_timers(mli);
}
MLD_UNLOCK();
}
/*
* 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_ifsoftc *mli)
{
MLD_LOCK_ASSERT();
if (mli->mli_version != MLD_VERSION_2 && --mli->mli_v1_timer == 0) {
/*
* MLDv1 Querier Present timer expired; revert to MLDv2.
*/
CTR5(KTR_MLD,
"%s: transition from v%d -> v%d on %p(%s)",
__func__, mli->mli_version, MLD_VERSION_2,
mli->mli_ifp, 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 int type)
{
struct ifnet *ifp;
struct in6_ifaddr *ia;
struct ip6_hdr *ip6;
struct mbuf *mh, *md;
struct mld_hdr *mld;
IN6_MULTI_LIST_LOCK_ASSERT();
MLD_LOCK_ASSERT();
ifp = in6m->in6m_ifp;
/* in process of being freed */
if (ifp == NULL)
return (0);
ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
/* ia may be NULL if link-local address is tentative. */
mh = m_gethdr(M_NOWAIT, MT_DATA);
if (mh == NULL) {
if (ia != NULL)
ifa_free(&ia->ia_ifa);
return (ENOMEM);
}
md = m_get(M_NOWAIT, MT_DATA);
if (md == NULL) {
m_free(mh);
if (ia != NULL)
ifa_free(&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.
*/
M_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;
ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
ip6->ip6_dst = in6m->in6m_addr;
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;
mld_dispatch_packet(mh);
if (ia != NULL)
ifa_free(&ia->ia_ifa);
return (0);
}
/*
* Process a state change from the upper layer for the given IPv6 group.
*
* Each socket holds a reference on the in_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 PR_FASTHZ 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.
*
* VIMAGE: curvnet should have been set by caller, as this routine
* is called from the socket option handlers.
*/
int
mld_change_state(struct in6_multi *inm, const int delay)
{
struct mld_ifsoftc *mli;
struct ifnet *ifp;
int error;
IN6_MULTI_LIST_LOCK_ASSERT();
error = 0;
/*
* Check if the in6_multi has already been disconnected.
*/
if (inm->in6m_ifp == NULL) {
CTR1(KTR_MLD, "%s: inm is disconnected", __func__);
return (0);
}
/*
* Try to detect if the upper layer just asked us to change state
* for an interface which has now gone away.
*/
KASSERT(inm->in6m_ifma != NULL, ("%s: no ifma", __func__));
ifp = inm->in6m_ifma->ifma_ifp;
if (ifp == NULL)
return (0);
/*
* Sanity check that netinet6's notion of ifp is the
* same as net's.
*/
KASSERT(inm->in6m_ifp == ifp, ("%s: bad ifp", __func__));
MLD_LOCK();
mli = MLD_IFINFO(ifp);
KASSERT(mli != NULL, ("%s: no mld_ifsoftc for ifp %p", __func__, ifp));
/*
* 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) {
CTR3(KTR_MLD, "%s: inm transition %d -> %d", __func__,
inm->in6m_st[0].iss_fmode, inm->in6m_st[1].iss_fmode);
if (inm->in6m_st[0].iss_fmode == MCAST_UNDEFINED) {
CTR1(KTR_MLD, "%s: initial join", __func__);
error = mld_initial_join(inm, mli, delay);
goto out_locked;
} else if (inm->in6m_st[1].iss_fmode == MCAST_UNDEFINED) {
CTR1(KTR_MLD, "%s: final leave", __func__);
mld_final_leave(inm, mli);
goto out_locked;
}
} else {
CTR1(KTR_MLD, "%s: filter set change", __func__);
}
error = mld_handle_state_change(inm, mli);
out_locked:
MLD_UNLOCK();
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 PR_FASTHZ).
*/
static int
mld_initial_join(struct in6_multi *inm, struct mld_ifsoftc *mli,
const int delay)
{
struct ifnet *ifp;
struct mbufq *mq;
int error, retval, syncstates;
int odelay;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
CTR4(KTR_MLD, "%s: initial join %s on ifp %p(%s)",
__func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
inm->in6m_ifp, if_name(inm->in6m_ifp));
error = 0;
syncstates = 1;
ifp = inm->in6m_ifp;
IN6_MULTI_LIST_LOCK_ASSERT();
MLD_LOCK_ASSERT();
KASSERT(mli && mli->mli_ifp == ifp, ("%s: inconsistent ifp", __func__));
/*
* Groups joined on loopback or marked as 'not reported',
* enter the MLD_SILENT_MEMBER state and
* are never reported in any protocol exchanges.
* All other groups enter the appropriate state machine
* for the version in use on this link.
* A link marked as MLIF_SILENT causes MLD to be completely
* disabled for the link.
*/
if ((ifp->if_flags & IFF_LOOPBACK) ||
(mli->mli_flags & MLIF_SILENT) ||
!mld_is_addr_reported(&inm->in6m_addr)) {
CTR1(KTR_MLD,
"%s: not kicking state machine for silent group", __func__);
inm->in6m_state = MLD_SILENT_MEMBER;
inm->in6m_timer = 0;
} else {
/*
* Deal with overlapping in_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.
*/
if (mli->mli_version == MLD_VERSION_2 &&
inm->in6m_state == MLD_LEAVING_MEMBER) {
inm->in6m_refcount--;
MPASS(inm->in6m_refcount > 0);
}
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 * PR_FASTHZ);
if (delay) {
inm->in6m_timer = max(delay, odelay);
V_current_state_timers_running6 = 1;
} else {
inm->in6m_state = MLD_IDLE_MEMBER;
error = mld_v1_transmit_report(inm,
MLD_LISTENER_REPORT);
if (error == 0) {
inm->in6m_timer = odelay;
V_current_state_timers_running6 = 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.
*/
mq = &inm->in6m_scq;
mbufq_drain(mq);
retval = mld_v2_enqueue_group_record(mq, inm, 1,
0, 0, (mli->mli_flags & MLIF_USEALLOW));
CTR2(KTR_MLD, "%s: enqueue record = %d",
__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_fasttimo (~200ms),
* 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.
*/
KASSERT(mli->mli_rv > 1,
("%s: invalid robustness %d", __func__,
mli->mli_rv));
inm->in6m_scrv = mli->mli_rv;
if (delay) {
if (inm->in6m_sctimer > 1) {
inm->in6m_sctimer =
min(inm->in6m_sctimer, delay);
} else
inm->in6m_sctimer = delay;
} else
inm->in6m_sctimer = 1;
V_state_change_timers_running6 = 1;
error = 0;
break;
}
}
/*
* 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);
CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
ip6_sprintf(ip6tbuf, &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_ifsoftc *mli)
{
struct ifnet *ifp;
int retval;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
CTR4(KTR_MLD, "%s: state change for %s on ifp %p(%s)",
__func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
inm->in6m_ifp, if_name(inm->in6m_ifp));
ifp = inm->in6m_ifp;
IN6_MULTI_LIST_LOCK_ASSERT();
MLD_LOCK_ASSERT();
KASSERT(mli && mli->mli_ifp == ifp,
("%s: inconsistent ifp", __func__));
if ((ifp->if_flags & IFF_LOOPBACK) ||
(mli->mli_flags & MLIF_SILENT) ||
!mld_is_addr_reported(&inm->in6m_addr) ||
(mli->mli_version != MLD_VERSION_2)) {
if (!mld_is_addr_reported(&inm->in6m_addr)) {
CTR1(KTR_MLD,
"%s: not kicking state machine for silent group", __func__);
}
CTR1(KTR_MLD, "%s: nothing to do", __func__);
in6m_commit(inm);
CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
ip6_sprintf(ip6tbuf, &inm->in6m_addr),
if_name(inm->in6m_ifp));
return (0);
}
mbufq_drain(&inm->in6m_scq);
retval = mld_v2_enqueue_group_record(&inm->in6m_scq, inm, 1, 0, 0,
(mli->mli_flags & MLIF_USEALLOW));
CTR2(KTR_MLD, "%s: enqueue record = %d", __func__, retval);
if (retval <= 0)
return (-retval);
/*
* If record(s) were enqueued, start the state-change
* report timer for this group.
*/
inm->in6m_scrv = mli->mli_rv;
inm->in6m_sctimer = 1;
V_state_change_timers_running6 = 1;
return (0);
}
/*
* 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_ifsoftc *mli)
{
int syncstates;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
syncstates = 1;
CTR4(KTR_MLD, "%s: final leave %s on ifp %p(%s)",
__func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
inm->in6m_ifp, if_name(inm->in6m_ifp));
IN6_MULTI_LIST_LOCK_ASSERT();
MLD_LOCK_ASSERT();
switch (inm->in6m_state) {
case MLD_NOT_MEMBER:
case MLD_SILENT_MEMBER:
case MLD_LEAVING_MEMBER:
/* Already leaving or left; do nothing. */
CTR1(KTR_MLD,
"%s: not kicking state machine for silent group", __func__);
break;
case MLD_REPORTING_MEMBER:
case MLD_IDLE_MEMBER:
case MLD_G_QUERY_PENDING_MEMBER:
case MLD_SG_QUERY_PENDING_MEMBER:
if (mli->mli_version == MLD_VERSION_1) {
#ifdef INVARIANTS
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",
__func__);
#endif
mld_v1_transmit_report(inm, MLD_LISTENER_DONE);
inm->in6m_state = MLD_NOT_MEMBER;
V_current_state_timers_running6 = 1;
} 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 fast timeout,
* giving us an opportunity to merge reports.
*/
mbufq_drain(&inm->in6m_scq);
inm->in6m_timer = 0;
inm->in6m_scrv = mli->mli_rv;
CTR4(KTR_MLD, "%s: Leaving %s/%s with %d "
"pending retransmissions.", __func__,
ip6_sprintf(ip6tbuf, &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;
in6m_acquire_locked(inm);
retval = mld_v2_enqueue_group_record(
&inm->in6m_scq, inm, 1, 0, 0,
(mli->mli_flags & MLIF_USEALLOW));
KASSERT(retval != 0,
("%s: enqueue record = %d", __func__,
retval));
inm->in6m_state = MLD_LEAVING_MEMBER;
inm->in6m_sctimer = 1;
V_state_change_timers_running6 = 1;
syncstates = 0;
}
break;
}
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);
CTR3(KTR_MLD, "%s: T1 -> T0 for %s/%s", __func__,
ip6_sprintf(ip6tbuf, &inm->in6m_addr),
if_name(inm->in6m_ifp));
inm->in6m_st[1].iss_fmode = MCAST_UNDEFINED;
CTR3(KTR_MLD, "%s: T1 now MCAST_UNDEFINED for %p/%s",
__func__, &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 mbufq *mq, 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;
struct mbuf *m0, *m, *md;
int is_filter_list_change;
int minrec0len, m0srcs, msrcs, nbytes, off;
int record_has_sources;
int now;
int type;
uint8_t mode;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
IN6_MULTI_LIST_LOCK_ASSERT();
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 = 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) {
CTR1(KTR_MLD, "%s: change to EXCLUDE",
__func__);
type = MLD_CHANGE_TO_EXCLUDE_MODE;
} else {
CTR1(KTR_MLD, "%s: change to INCLUDE",
__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;
KASSERT(inm->in6m_st[1].iss_asm == 0,
("%s: inm %p is INCLUDE but ASM count is %d",
__func__, inm, inm->in6m_st[1].iss_asm));
}
}
/*
* Generate the filter list changes using a separate function.
*/
if (is_filter_list_change)
return (mld_v2_enqueue_filter_change(mq, inm));
if (type == MLD_DO_NOTHING) {
CTR3(KTR_MLD, "%s: nothing to do for %s/%s",
__func__, ip6_sprintf(ip6tbuf, &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);
CTR4(KTR_MLD, "%s: queueing %s for %s/%s", __func__,
mld_rec_type_to_str(type),
ip6_sprintf(ip6tbuf, &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 = mbufq_last(mq);
if (!is_group_query &&
m0 != NULL &&
(m0->m_pkthdr.PH_vt.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;
CTR1(KTR_MLD, "%s: use existing packet", __func__);
} else {
if (mbufq_full(mq)) {
CTR1(KTR_MLD, "%s: outbound queue full", __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_NOWAIT, MT_DATA, M_PKTHDR);
if (m == NULL)
m = m_gethdr(M_NOWAIT, MT_DATA);
if (m == NULL)
return (-ENOMEM);
mld_save_context(m, ifp);
CTR1(KTR_MLD, "%s: allocated first packet", __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);
CTR1(KTR_MLD, "%s: m_append() failed.", __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) {
CTR2(KTR_MLD, "%s: visit node %s", __func__,
ip6_sprintf(ip6tbuf, &ims->im6s_addr));
now = im6s_get_mode(inm, ims, 1);
CTR2(KTR_MLD, "%s: node is %d", __func__, now);
if ((now != mode) ||
(now == mode &&
(!use_block_allow && mode == MCAST_UNDEFINED))) {
CTR1(KTR_MLD, "%s: skip node", __func__);
continue;
}
if (is_source_query && ims->im6s_stp == 0) {
CTR1(KTR_MLD, "%s: skip unrecorded node",
__func__);
continue;
}
CTR1(KTR_MLD, "%s: append node", __func__);
if (!m_append(m, sizeof(struct in6_addr),
(void *)&ims->im6s_addr)) {
if (m != m0)
m_freem(m);
CTR1(KTR_MLD, "%s: m_append() failed.",
__func__);
return (-ENOMEM);
}
nbytes += sizeof(struct in6_addr);
++msrcs;
if (msrcs == m0srcs)
break;
}
CTR2(KTR_MLD, "%s: msrcs is %d this packet", __func__,
msrcs);
pmr->mr_numsrc = htons(msrcs);
nbytes += (msrcs * sizeof(struct in6_addr));
}
if (is_source_query && msrcs == 0) {
CTR1(KTR_MLD, "%s: no recorded sources to report", __func__);
if (m != m0)
m_freem(m);
return (0);
}
/*
* We are good to go with first packet.
*/
if (m != m0) {
CTR1(KTR_MLD, "%s: enqueueing first packet", __func__);
m->m_pkthdr.PH_vt.vt_nrecs = 1;
mbufq_enqueue(mq, m);
} else
m->m_pkthdr.PH_vt.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 (mbufq_full(mq)) {
CTR1(KTR_MLD, "%s: outbound queue full", __func__);
return (-ENOMEM);
}
m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
if (m == NULL)
m = m_gethdr(M_NOWAIT, 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);
CTR1(KTR_MLD, "%s: allocated next packet", __func__);
if (!m_append(m, sizeof(struct mldv2_record), (void *)&mr)) {
if (m != m0)
m_freem(m);
CTR1(KTR_MLD, "%s: m_append() failed.", __func__);
return (-ENOMEM);
}
m->m_pkthdr.PH_vt.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) {
CTR2(KTR_MLD, "%s: visit node %s",
__func__, ip6_sprintf(ip6tbuf, &ims->im6s_addr));
now = im6s_get_mode(inm, ims, 1);
if ((now != mode) ||
(now == mode &&
(!use_block_allow && mode == MCAST_UNDEFINED))) {
CTR1(KTR_MLD, "%s: skip node", __func__);
continue;
}
if (is_source_query && ims->im6s_stp == 0) {
CTR1(KTR_MLD, "%s: skip unrecorded node",
__func__);
continue;
}
CTR1(KTR_MLD, "%s: append node", __func__);
if (!m_append(m, sizeof(struct in6_addr),
(void *)&ims->im6s_addr)) {
if (m != m0)
m_freem(m);
CTR1(KTR_MLD, "%s: m_append() failed.",
__func__);
return (-ENOMEM);
}
++msrcs;
if (msrcs == m0srcs)
break;
}
pmr->mr_numsrc = htons(msrcs);
nbytes += (msrcs * sizeof(struct in6_addr));
CTR1(KTR_MLD, "%s: enqueueing next packet", __func__);
mbufq_enqueue(mq, 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 mbufq *mq, 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;
struct mbuf *m, *m0, *md;
int m0srcs, nbytes, npbytes, off, rsrcs, schanged;
int nallow, nblock;
uint8_t mode, now, then;
rectype_t crt, drt, nrt;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
IN6_MULTI_LIST_LOCK_ASSERT();
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 = 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 = mbufq_last(mq);
if (m0 != NULL &&
(m0->m_pkthdr.PH_vt.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);
CTR1(KTR_MLD,
"%s: use previous packet", __func__);
} else {
m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
if (m == NULL)
m = m_gethdr(M_NOWAIT, MT_DATA);
if (m == NULL) {
CTR1(KTR_MLD,
"%s: m_get*() failed", __func__);
return (-ENOMEM);
}
m->m_pkthdr.PH_vt.vt_nrecs = 0;
mld_save_context(m, ifp);
m0srcs = (ifp->if_mtu - MLD_MTUSPACE -
sizeof(struct mldv2_record)) /
sizeof(struct in6_addr);
npbytes = 0;
CTR1(KTR_MLD,
"%s: allocated new packet", __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);
CTR1(KTR_MLD,
"%s: m_append() failed", __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) {
CTR2(KTR_MLD, "%s: visit node %s", __func__,
ip6_sprintf(ip6tbuf, &ims->im6s_addr));
now = im6s_get_mode(inm, ims, 1);
then = im6s_get_mode(inm, ims, 0);
CTR3(KTR_MLD, "%s: mode: t0 %d, t1 %d",
__func__, then, now);
if (now == then) {
CTR1(KTR_MLD,
"%s: skip unchanged", __func__);
continue;
}
if (mode == MCAST_EXCLUDE &&
now == MCAST_INCLUDE) {
CTR1(KTR_MLD,
"%s: skip IN src on EX group",
__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);
CTR1(KTR_MLD,
"%s: m_append() failed", __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) {
CTR1(KTR_MLD,
"%s: m_free(m)", __func__);
m_freem(m);
} else {
CTR1(KTR_MLD,
"%s: m_adj(m, -mr)", __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(rsrcs);
/*
* Count the new group record, and enqueue this
* packet if it wasn't already queued.
*/
m->m_pkthdr.PH_vt.vt_nrecs++;
if (m != m0)
mbufq_enqueue(mq, m);
nbytes += npbytes;
} while (nims != NULL);
drt |= crt;
crt = (~crt & REC_FULL);
}
CTR3(KTR_MLD, "%s: queued %d ALLOW_NEW, %d BLOCK_OLD", __func__,
nallow, nblock);
return (nbytes);
}
static int
mld_v2_merge_state_changes(struct in6_multi *inm, struct mbufq *scq)
{
struct mbufq *gq;
struct mbuf *m; /* pending state-change */
struct mbuf *m0; /* copy of pending state-change */
struct mbuf *mt; /* last state-change in packet */
int docopy, domerge;
u_int recslen;
docopy = 0;
domerge = 0;
recslen = 0;
IN6_MULTI_LIST_LOCK_ASSERT();
MLD_LOCK_ASSERT();
/*
* 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 KTR
if (mbufq_first(gq) == NULL) {
CTR2(KTR_MLD, "%s: WARNING: queue for inm %p is empty",
__func__, inm);
}
#endif
m = mbufq_first(gq);
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 = mbufq_last(scq);
if (mt != NULL) {
recslen = m_length(m, NULL);
if ((mt->m_pkthdr.PH_vt.vt_nrecs +
m->m_pkthdr.PH_vt.vt_nrecs <=
MLD_V2_REPORT_MAXRECS) &&
(mt->m_pkthdr.len + recslen <=
(inm->in6m_ifp->if_mtu - MLD_MTUSPACE)))
domerge = 1;
}
if (!domerge && mbufq_full(gq)) {
CTR2(KTR_MLD,
"%s: outbound queue full, skipping whole packet %p",
__func__, m);
mt = m->m_nextpkt;
if (!docopy)
m_freem(m);
m = mt;
continue;
}
if (!docopy) {
CTR2(KTR_MLD, "%s: dequeueing %p", __func__, m);
m0 = mbufq_dequeue(gq);
m = m0->m_nextpkt;
} else {
CTR2(KTR_MLD, "%s: copying %p", __func__, m);
m0 = m_dup(m, M_NOWAIT);
if (m0 == NULL)
return (ENOMEM);
m0->m_nextpkt = NULL;
m = m->m_nextpkt;
}
if (!domerge) {
CTR3(KTR_MLD, "%s: queueing %p to scq %p)",
__func__, m0, scq);
mbufq_enqueue(scq, m0);
} else {
struct mbuf *mtl; /* last mbuf of packet mt */
CTR3(KTR_MLD, "%s: merging %p with ifscq tail %p)",
__func__, m0, mt);
mtl = m_last(mt);
m0->m_flags &= ~M_PKTHDR;
mt->m_pkthdr.len += recslen;
mt->m_pkthdr.PH_vt.vt_nrecs +=
m0->m_pkthdr.PH_vt.vt_nrecs;
mtl->m_next = m0;
}
}
return (0);
}
/*
* Respond to a pending MLDv2 General Query.
*/
static void
mld_v2_dispatch_general_query(struct mld_ifsoftc *mli)
{
struct epoch_tracker et;
struct ifmultiaddr *ifma;
struct ifnet *ifp;
struct in6_multi *inm;
int retval;
IN6_MULTI_LIST_LOCK_ASSERT();
MLD_LOCK_ASSERT();
KASSERT(mli->mli_version == MLD_VERSION_2,
("%s: called when version %d", __func__, mli->mli_version));
/*
* Check that there are some packets queued. If so, send them first.
* For large number of groups the reply to general query can take
* many packets, we should finish sending them before starting of
* queuing the new reply.
*/
if (mbufq_len(&mli->mli_gq) != 0)
goto send;
ifp = mli->mli_ifp;
NET_EPOCH_ENTER(et);
CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
inm = in6m_ifmultiaddr_get_inm(ifma);
if (inm == NULL)
continue;
KASSERT(ifp == inm->in6m_ifp,
("%s: inconsistent ifp", __func__));
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;
retval = mld_v2_enqueue_group_record(&mli->mli_gq,
inm, 0, 0, 0, 0);
CTR2(KTR_MLD, "%s: enqueue record = %d",
__func__, retval);
break;
case MLD_G_QUERY_PENDING_MEMBER:
case MLD_SG_QUERY_PENDING_MEMBER:
case MLD_LEAVING_MEMBER:
break;
}
}
NET_EPOCH_EXIT(et);
send:
mld_dispatch_queue(&mli->mli_gq, MLD_MAX_RESPONSE_BURST);
/*
* Slew transmission of bursts over 500ms intervals.
*/
if (mbufq_first(&mli->mli_gq) != NULL) {
mli->mli_v2_timer = 1 + MLD_RANDOM_DELAY(
MLD_RESPONSE_BURST_INTERVAL);
V_interface_timers_running6 = 1;
}
}
/*
* Transmit the next pending message in the output queue.
*
* VIMAGE: Needs to store/restore vnet pointer on a per-mbuf-chain basis.
* MRT: Nothing needs to be done, as MLD traffic is always local to
* a link and uses a link-scope multicast address.
*/
static void
mld_dispatch_packet(struct mbuf *m)
{
struct ip6_moptions im6o;
struct ifnet *ifp;
struct ifnet *oifp;
struct mbuf *m0;
struct mbuf *md;
struct ip6_hdr *ip6;
struct mld_hdr *mld;
int error;
int off;
int type;
uint32_t ifindex;
CTR2(KTR_MLD, "%s: transmit %p", __func__, m);
/*
* Set VNET image pointer from enqueued mbuf chain
* before doing anything else. Whilst we use interface
* indexes to guard against interface detach, they are
* unique to each VIMAGE and must be retrieved.
*/
ifindex = mld_restore_context(m);
/*
* Check if the ifnet still exists. This limits the scope of
* any race in the absence of a global ifp lock for low cost
* (an array lookup).
*/
ifp = ifnet_byindex(ifindex);
if (ifp == NULL) {
CTR3(KTR_MLD, "%s: dropped %p as ifindex %u went away.",
__func__, m, ifindex);
m_freem(m);
IP6STAT_INC(ip6s_noroute);
goto out;
}
im6o.im6o_multicast_hlim = 1;
im6o.im6o_multicast_loop = (V_ip6_mrouter != NULL);
im6o.im6o_multicast_ifp = ifp;
if (m->m_flags & M_MLDV1) {
m0 = m;
} else {
m0 = mld_v2_encap_report(ifp, m);
if (m0 == NULL) {
CTR2(KTR_MLD, "%s: dropped %p", __func__, m);
IP6STAT_INC(ip6s_odropped);
goto out;
}
}
mld_scrub_context(m0);
m_clrprotoflags(m);
m0->m_pkthdr.rcvif = V_loif;
ip6 = mtod(m0, struct ip6_hdr *);
#if 0
(void)in6_setscope(&ip6->ip6_dst, ifp, NULL); /* XXX LOR */
#else
/*
* XXX XXX Break some KPI rules to prevent an LOR which would
* occur if we called in6_setscope() at transmission.
* See comments at top of file.
*/
MLD_EMBEDSCOPE(&ip6->ip6_dst, ifp->if_index);
#endif
/*
* Retrieve the ICMPv6 type before handoff to ip6_output(),
* so we can bump the stats.
*/
md = m_getptr(m0, sizeof(struct ip6_hdr), &off);
mld = (struct mld_hdr *)(mtod(md, uint8_t *) + off);
type = mld->mld_type;
error = ip6_output(m0, &mld_po, NULL, IPV6_UNSPECSRC, &im6o,
&oifp, NULL);
if (error) {
CTR3(KTR_MLD, "%s: ip6_output(%p) = %d", __func__, m0, error);
goto out;
}
ICMP6STAT_INC(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;
}
}
out:
return;
}
/*
* 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;
KASSERT(ifp != NULL, ("%s: null ifp", __func__));
KASSERT((m->m_flags & M_PKTHDR),
("%s: mbuf chain %p is !M_PKTHDR", __func__, m));
/*
* RFC3590: OK to send as :: or tentative during DAD.
*/
ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
if (ia == NULL)
CTR1(KTR_MLD, "%s: warning: ia is NULL", __func__);
mh = m_gethdr(M_NOWAIT, MT_DATA);
if (mh == NULL) {
if (ia != NULL)
ifa_free(&ia->ia_ifa);
m_freem(m);
return (NULL);
}
M_ALIGN(mh, sizeof(struct ip6_hdr) + sizeof(struct mldv2_report));
mldreclen = m_length(m, NULL);
CTR2(KTR_MLD, "%s: mldreclen is %d", __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;
ip6->ip6_src = ia ? ia->ia_addr.sin6_addr : in6addr_any;
if (ia != NULL)
ifa_free(&ia->ia_ifa);
ip6->ip6_dst = in6addr_linklocal_allv2routers;
/* 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.PH_vt.vt_nrecs);
m->m_pkthdr.PH_vt.vt_nrecs = 0;
mh->m_next = m;
mld->mld_cksum = in6_cksum(mh, IPPROTO_ICMPV6,
sizeof(struct ip6_hdr), sizeof(struct mldv2_report) + mldreclen);
return (mh);
}
#ifdef KTR
static char *
mld_rec_type_to_str(const int type)
{
switch (type) {
case MLD_CHANGE_TO_EXCLUDE_MODE:
return "TO_EX";
break;
case MLD_CHANGE_TO_INCLUDE_MODE:
return "TO_IN";
break;
case MLD_MODE_IS_EXCLUDE:
return "MODE_EX";
break;
case MLD_MODE_IS_INCLUDE:
return "MODE_IN";
break;
case MLD_ALLOW_NEW_SOURCES:
return "ALLOW_NEW";
break;
case MLD_BLOCK_OLD_SOURCES:
return "BLOCK_OLD";
break;
default:
break;
}
return "unknown";
}
#endif
static void
mld_init(void *unused __unused)
{
CTR1(KTR_MLD, "%s: initializing", __func__);
MLD_LOCK_INIT();
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;
}
SYSINIT(mld_init, SI_SUB_PROTO_MC, SI_ORDER_MIDDLE, mld_init, NULL);
static void
mld_uninit(void *unused __unused)
{
CTR1(KTR_MLD, "%s: tearing down", __func__);
MLD_LOCK_DESTROY();
}
SYSUNINIT(mld_uninit, SI_SUB_PROTO_MC, SI_ORDER_MIDDLE, mld_uninit, NULL);
static void
vnet_mld_init(const void *unused __unused)
{
CTR1(KTR_MLD, "%s: initializing", __func__);
LIST_INIT(&V_mli_head);
}
VNET_SYSINIT(vnet_mld_init, SI_SUB_PROTO_MC, SI_ORDER_ANY, vnet_mld_init,
NULL);
static void
vnet_mld_uninit(const void *unused __unused)
{
/* This can happen if we shutdown the network stack. */
CTR1(KTR_MLD, "%s: tearing down", __func__);
}
VNET_SYSUNINIT(vnet_mld_uninit, SI_SUB_PROTO_MC, SI_ORDER_ANY, vnet_mld_uninit,
NULL);
static int
mld_modevent(module_t mod, int type, void *unused __unused)
{
switch (type) {
case MOD_LOAD:
case MOD_UNLOAD:
break;
default:
return (EOPNOTSUPP);
}
return (0);
}
static moduledata_t mld_mod = {
"mld",
mld_modevent,
0
};
DECLARE_MODULE(mld, mld_mod, SI_SUB_PROTO_MC, SI_ORDER_ANY);
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