d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
dcd3605677
freebsd-skq/sys/netinet6/mld6.c
jhb 4ef366671a Convert all users of IF_ADDR_LOCK to use new locking macros that specify 
either a read lock or write lock.

Reviewed by:	bz
MFC after:	2 weeks
2012-01-05 19:00:36 +00:00

3320 lines
88 KiB
C
Raw Blame History

/*-
* 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)igmp.c 8.1 (Berkeley) 7/19/93
*/
#include <sys/cdefs.h>
__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/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_ifinfo *
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 ifqueue *, int);
static void mld_final_leave(struct in6_multi *, struct mld_ifinfo *);
static void mld_fasttimo_vnet(void);
static int mld_handle_state_change(struct in6_multi *,
struct mld_ifinfo *);
static int mld_initial_join(struct in6_multi *, struct mld_ifinfo *,
const int);
#ifdef KTR
static char * mld_rec_type_to_str(const int);
#endif
static void mld_set_version(struct mld_ifinfo *, 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 mld_ifinfo *,
struct in6_multi *);
static void mld_v1_process_querier_timers(struct mld_ifinfo *);
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_ifinfo *);
static void 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 *,
struct mld_ifinfo *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.
*/
static VNET_DEFINE(struct timeval, mld_gsrdelay) = {10, 0};
static VNET_DEFINE(LIST_HEAD(, mld_ifinfo), mli_head);
static VNET_DEFINE(int, interface_timers_running6);
static VNET_DEFINE(int, state_change_timers_running6);
static VNET_DEFINE(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_VNET_PROC(_net_inet6_mld, OID_AUTO, gsrdelay,
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_RW,
&mld_v1enable, 0, "Enable fallback to MLDv1");
TUNABLE_INT("net.inet6.mld.v1enable", &mld_v1enable);
static int mld_use_allow = 1;
SYSCTL_INT(_net_inet6_mld, OID_AUTO, use_allow, CTLFLAG_RW,
&mld_use_allow, 0, "Use ALLOW/BLOCK for RFC 4604 SSM joins/leaves");
TUNABLE_INT("net.inet6.mld.use_allow", &mld_use_allow);
/*
* 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.header = ifp->if_vnet;
#endif /* VIMAGE */
m->m_pkthdr.flowid = ifp->if_index;
}
static __inline void
mld_scrub_context(struct mbuf *m)
{
m->m_pkthdr.header = 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.header,
("%s: called when curvnet was not restored", __func__));
#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_ifinfo 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_ifinfo *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();
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) {
error = SYSCTL_OUT(req, mli,
sizeof(struct mld_ifinfo));
break;
}
}
out_locked:
MLD_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 ifqueue *ifq, int limit)
{
struct mbuf *m;
for (;;) {
_IF_DEQUEUE(ifq, m);
if (m == NULL)
break;
CTR3(KTR_MLD, "%s: dispatch %p from %p", __func__, ifq, 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_ifinfo *
mld_domifattach(struct ifnet *ifp)
{
struct mld_ifinfo *mli;
CTR3(KTR_MLD, "%s: called for ifp %p(%s)",
__func__, ifp, ifp->if_xname);
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_ifinfo *
mli_alloc_locked(/*const*/ struct ifnet *ifp)
{
struct mld_ifinfo *mli;
MLD_LOCK_ASSERT();
mli = malloc(sizeof(struct mld_ifinfo), 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;
SLIST_INIT(&mli->mli_relinmhead);
/*
* Responses to general queries are subject to bounds.
*/
IFQ_SET_MAXLEN(&mli->mli_gq, MLD_MAX_RESPONSE_PACKETS);
LIST_INSERT_HEAD(&V_mli_head, mli, mli_link);
CTR2(KTR_MLD, "allocate mld_ifinfo for ifp %p(%s)",
ifp, ifp->if_xname);
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 mld_ifinfo *mli;
struct ifmultiaddr *ifma;
struct in6_multi *inm, *tinm;
CTR3(KTR_MLD, "%s: called for ifp %p(%s)", __func__, ifp,
ifp->if_xname);
IN6_MULTI_LOCK_ASSERT();
MLD_LOCK();
mli = MLD_IFINFO(ifp);
if (mli->mli_version == MLD_VERSION_2) {
IF_ADDR_RLOCK(ifp);
TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
if (ifma->ifma_addr->sa_family != AF_INET6 ||
ifma->ifma_protospec == NULL)
continue;
inm = (struct in6_multi *)ifma->ifma_protospec;
if (inm->in6m_state == MLD_LEAVING_MEMBER) {
SLIST_INSERT_HEAD(&mli->mli_relinmhead,
inm, in6m_nrele);
}
in6m_clear_recorded(inm);
}
IF_ADDR_RUNLOCK(ifp);
SLIST_FOREACH_SAFE(inm, &mli->mli_relinmhead, in6m_nrele,
tinm) {
SLIST_REMOVE_HEAD(&mli->mli_relinmhead, in6m_nrele);
in6m_release_locked(inm);
}
}
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, ifp->if_xname);
MLD_LOCK();
mli_delete_locked(ifp);
MLD_UNLOCK();
}
static void
mli_delete_locked(const struct ifnet *ifp)
{
struct mld_ifinfo *mli, *tmli;
CTR3(KTR_MLD, "%s: freeing mld_ifinfo for ifp %p(%s)",
__func__, ifp, ifp->if_xname);
MLD_LOCK_ASSERT();
LIST_FOREACH_SAFE(mli, &V_mli_head, mli_link, tmli) {
if (mli->mli_ifp == ifp) {
/*
* Free deferred General Query responses.
*/
_IF_DRAIN(&mli->mli_gq);
LIST_REMOVE(mli, mli_link);
KASSERT(SLIST_EMPTY(&mli->mli_relinmhead),
("%s: there are dangling in_multi references",
__func__));
free(mli, M_MLD);
return;
}
}
#ifdef INVARIANTS
panic("%s: mld_ifinfo not found for ifp %p\n", __func__, ifp);
#endif
}
/*
* 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 ifmultiaddr *ifma;
struct mld_ifinfo *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, ifp->if_xname);
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, ifp->if_xname);
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_LOCK();
MLD_LOCK();
/*
* Switch to MLDv1 host compatibility mode.
*/
mli = MLD_IFINFO(ifp);
KASSERT(mli != NULL, ("%s: no mld_ifinfo 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;
IF_ADDR_RLOCK(ifp);
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, ifp->if_xname);
TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
if (ifma->ifma_addr->sa_family != AF_INET6 ||
ifma->ifma_protospec == NULL)
continue;
inm = (struct in6_multi *)ifma->ifma_protospec;
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, ifp->if_xname);
mld_v1_update_group(inm, timer);
}
/* XXX Clear embedded scope ID as userland won't expect it. */
in6_clearscope(&mld->mld_addr);
}
IF_ADDR_RUNLOCK(ifp);
MLD_UNLOCK();
IN6_MULTI_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),
inm->in6m_ifp->if_xname, timer);
IN6_MULTI_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_ifinfo *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
is_general_query = 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, ifp->if_xname);
return (0);
}
CTR2(KTR_MLD, "input v2 query on ifp %p(%s)", ifp, ifp->if_xname);
mld = (struct mldv2_query *)(mtod(m, uint8_t *) + off);
maxdelay = ntohs(mld->mld_maxdelay); /* in 1/10ths of a second */
if (maxdelay >= 32678) {
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)) {
/*
* General Queries SHOULD be directed to ff02::1.
* A general query with a source list has undefined
* behaviour; discard it.
*/
struct in6_addr dst;
dst = ip6->ip6_dst;
in6_clearscope(&dst);
if (!IN6_ARE_ADDR_EQUAL(&dst, &in6addr_linklocal_allnodes) ||
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_LOCK();
MLD_LOCK();
mli = MLD_IFINFO(ifp);
KASSERT(mli != NULL, ("%s: no mld_ifinfo 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, ifp->if_xname);
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 {
/*
* 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.
*/
IF_ADDR_RLOCK(ifp);
inm = in6m_lookup_locked(ifp, &mld->mld_addr);
if (inm == NULL) {
IF_ADDR_RUNLOCK(ifp);
goto out_locked;
}
if (nsrc > 0) {
if (!ratecheck(&inm->in6m_lastgsrtv,
&V_mld_gsrdelay)) {
CTR1(KTR_MLD, "%s: GS query throttled.",
__func__);
IF_ADDR_RUNLOCK(ifp);
goto out_locked;
}
}
CTR2(KTR_MLD, "process v2 group query on ifp %p(%s)",
ifp, ifp->if_xname);
/*
* 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);
IF_ADDR_RUNLOCK(ifp);
}
out_locked:
MLD_UNLOCK();
IN6_MULTI_UNLOCK();
return (0);
}
/*
* 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, struct mld_ifinfo *mli,
int timer, struct mbuf *m0, const int off)
{
struct mldv2_query *mld;
int retval;
uint16_t nsrc;
IN6_MULTI_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 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, ifp->if_xname);
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, ifp->if_xname);
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, ifp->if_xname);
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, ifp->if_xname);
/*
* 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_LOCK();
MLD_LOCK();
IF_ADDR_RLOCK(ifp);
/*
* 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_ifinfo *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, ifp->if_xname);
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:
IF_ADDR_RUNLOCK(ifp);
MLD_UNLOCK();
IN6_MULTI_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)
{
VNET_ITERATOR_DECL(vnet_iter);
VNET_LIST_RLOCK_NOSLEEP();
VNET_FOREACH(vnet_iter) {
CURVNET_SET(vnet_iter);
mld_fasttimo_vnet();
CURVNET_RESTORE();
}
VNET_LIST_RUNLOCK_NOSLEEP();
}
/*
* Fast timeout handler (per-vnet).
*
* VIMAGE: Assume caller has set up our curvnet.
*/
static void
mld_fasttimo_vnet(void)
{
struct ifqueue scq; /* State-change packets */
struct ifqueue qrq; /* Query response packets */
struct ifnet *ifp;
struct mld_ifinfo *mli;
struct ifmultiaddr *ifma;
struct in6_multi *inm, *tinm;
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_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);
memset(&qrq, 0, sizeof(struct ifqueue));
IFQ_SET_MAXLEN(&qrq, MLD_MAX_G_GS_PACKETS);
memset(&scq, 0, sizeof(struct ifqueue));
IFQ_SET_MAXLEN(&scq, MLD_MAX_STATE_CHANGE_PACKETS);
}
IF_ADDR_RLOCK(ifp);
TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
if (ifma->ifma_addr->sa_family != AF_INET6 ||
ifma->ifma_protospec == NULL)
continue;
inm = (struct in6_multi *)ifma->ifma_protospec;
switch (mli->mli_version) {
case MLD_VERSION_1:
mld_v1_process_group_timer(mli, inm);
break;
case MLD_VERSION_2:
mld_v2_process_group_timers(mli, &qrq,
&scq, inm, uri_fasthz);
break;
}
}
IF_ADDR_RUNLOCK(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.
*/
SLIST_FOREACH_SAFE(inm, &mli->mli_relinmhead,
in6m_nrele, tinm) {
SLIST_REMOVE_HEAD(&mli->mli_relinmhead,
in6m_nrele);
(void)mld_v1_transmit_report(inm,
MLD_LISTENER_REPORT);
}
break;
case MLD_VERSION_2:
mld_dispatch_queue(&qrq, 0);
mld_dispatch_queue(&scq, 0);
/*
* Free the in_multi reference(s) for
* this lifecycle.
*/
SLIST_FOREACH_SAFE(inm, &mli->mli_relinmhead,
in6m_nrele, tinm) {
SLIST_REMOVE_HEAD(&mli->mli_relinmhead,
in6m_nrele);
in6m_release_locked(inm);
}
break;
}
}
out_locked:
MLD_UNLOCK();
IN6_MULTI_UNLOCK();
}
/*
* Update host report group timer.
* Will update the global pending timer flags.
*/
static void
mld_v1_process_group_timer(struct mld_ifinfo *mli, struct in6_multi *inm)
{
int report_timer_expired;
IN6_MULTI_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(&mli->mli_relinmhead, inm,
in6m_nrele);
}
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_fasthz)
{
int query_response_timer_expired;
int state_change_retransmit_timer_expired;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
IN6_MULTI_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),
inm->in6m_ifp->if_xname);
/*
* 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;
SLIST_INSERT_HEAD(&mli->mli_relinmhead,
inm, in6m_nrele);
}
}
break;
}
}
/*
* Switch to a different version on the given interface,
* as per Section 9.12.
*/
static void
mld_set_version(struct mld_ifinfo *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, mli->mli_ifp->if_xname);
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_ifinfo *mli)
{
struct ifmultiaddr *ifma;
struct ifnet *ifp;
struct in6_multi *inm, *tinm;
CTR3(KTR_MLD, "%s: cancel v2 timers on ifp %p(%s)", __func__,
mli->mli_ifp, mli->mli_ifp->if_xname);
IN6_MULTI_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_RLOCK(ifp);
TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
if (ifma->ifma_addr->sa_family != AF_INET6)
continue;
inm = (struct in6_multi *)ifma->ifma_protospec;
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 {}.
*/
SLIST_INSERT_HEAD(&mli->mli_relinmhead, inm,
in6m_nrele);
/* 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.
*/
_IF_DRAIN(&inm->in6m_scq);
break;
}
}
IF_ADDR_RUNLOCK(ifp);
SLIST_FOREACH_SAFE(inm, &mli->mli_relinmhead, in6m_nrele, tinm) {
SLIST_REMOVE_HEAD(&mli->mli_relinmhead, in6m_nrele);
in6m_release_locked(inm);
}
}
/*
* 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_ifinfo *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_ifinfo *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, mli->mli_ifp->if_xname);
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_LOCK_ASSERT();
MLD_LOCK_ASSERT();
ifp = in6m->in6m_ifp;
ia = in6ifa_ifpforlinklocal(ifp, IN6_IFF_NOTREADY|IN6_IFF_ANYCAST);
/* ia may be NULL if link-local address is tentative. */
MGETHDR(mh, M_DONTWAIT, MT_HEADER);
if (mh == NULL) {
if (ia != NULL)
ifa_free(&ia->ia_ifa);
return (ENOMEM);
}
MGET(md, M_DONTWAIT, 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.
*/
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;
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_ifinfo *mli;
struct ifnet *ifp;
int error;
IN6_MULTI_LOCK_ASSERT();
error = 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) {
/*
* 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_ifinfo 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_ifinfo *mli,
const int delay)
{
struct ifnet *ifp;
struct ifqueue *ifq;
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, inm->in6m_ifp->if_xname);
error = 0;
syncstates = 1;
ifp = inm->in6m_ifp;
IN6_MULTI_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)
in6m_release_locked(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 * 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.
*/
ifq = &inm->in6m_scq;
_IF_DRAIN(ifq);
retval = mld_v2_enqueue_group_record(ifq, 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),
inm->in6m_ifp->if_xname);
}
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 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, inm->in6m_ifp->if_xname);
ifp = inm->in6m_ifp;
IN6_MULTI_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),
inm->in6m_ifp->if_xname);
return (0);
}
_IF_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_ifinfo *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, inm->in6m_ifp->if_xname);
IN6_MULTI_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;
} 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.
*/
_IF_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),
inm->in6m_ifp->if_xname, 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),
inm->in6m_ifp->if_xname);
inm->in6m_st[1].iss_fmode = MCAST_UNDEFINED;
CTR3(KTR_MLD, "%s: T1 now MCAST_UNDEFINED for %p/%s",
__func__, &inm->in6m_addr, inm->in6m_ifp->if_xname);
}
}
/*
* 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;
struct mbuf *m0, *m, *md;
int error, 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_LOCK_ASSERT();
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 = 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(ifq, inm));
if (type == MLD_DO_NOTHING) {
CTR3(KTR_MLD, "%s: nothing to do for %s/%s",
__func__, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
inm->in6m_ifp->if_xname);
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),
inm->in6m_ifp->if_xname);
/*
* 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.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 (_IF_QFULL(ifq)) {
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_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);
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;
_IF_ENQUEUE(ifq, 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 (_IF_QFULL(ifq)) {
CTR1(KTR_MLD, "%s: outbound queue full", __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);
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__);
_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;
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_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 = ifq->ifq_tail;
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_DONTWAIT, MT_DATA, M_PKTHDR);
if (m == NULL)
m = m_gethdr(M_DONTWAIT, 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)
_IF_ENQUEUE(ifq, 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 ifqueue *ifscq)
{
struct ifqueue *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_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 (gq->ifq_head == NULL) {
CTR2(KTR_MLD, "%s: WARNING: queue for inm %p is empty",
__func__, inm);
}
#endif
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, 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 && _IF_QFULL(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);
_IF_DEQUEUE(gq, m0);
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 ifscq %p)",
__func__, m0, ifscq);
_IF_ENQUEUE(ifscq, 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_ifinfo *mli)
{
struct ifmultiaddr *ifma;
struct ifnet *ifp;
struct in6_multi *inm;
int retval;
IN6_MULTI_LOCK_ASSERT();
MLD_LOCK_ASSERT();
KASSERT(mli->mli_version == MLD_VERSION_2,
("%s: called when version %d", __func__, mli->mli_version));
ifp = mli->mli_ifp;
IF_ADDR_RLOCK(ifp);
TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
if (ifma->ifma_addr->sa_family != AF_INET6 ||
ifma->ifma_protospec == NULL)
continue;
inm = (struct in6_multi *)ifma->ifma_protospec;
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;
}
}
IF_ADDR_RUNLOCK(ifp);
mld_dispatch_queue(&mli->mli_gq, MLD_MAX_RESPONSE_BURST);
/*
* Slew transmission of bursts over 500ms intervals.
*/
if (mli->mli_gq.ifq_head != 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->m_flags &= ~(M_PROTOFLAGS);
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__);
MGETHDR(mh, M_DONTWAIT, MT_HEADER);
if (mh == NULL) {
if (ia != NULL)
ifa_free(&ia->ia_ifa);
m_freem(m);
return (NULL);
}
MH_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_PSEUDO, 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_PSEUDO, 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_PSEUDO, SI_ORDER_ANY, vnet_mld_init,
NULL);
static void
vnet_mld_uninit(const void *unused __unused)
{
CTR1(KTR_MLD, "%s: tearing down", __func__);
KASSERT(LIST_EMPTY(&V_mli_head),
("%s: mli list not empty; ifnets not detached?", __func__));
}
VNET_SYSUNINIT(vnet_mld_uninit, SI_SUB_PSEUDO, 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_PSEUDO, SI_ORDER_ANY);
Reference in New Issue View Git Blame Copy Permalink