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freebsd-skq/sys/netinet6/in6_mcast.c
Kristof Provost 2ef5d803e3 in6_mcast: Return EADDRINUSE when we've already joined the group 
Distinguish between truly invalid requests and those that fail because
we've already joined the group. Both cases fail, but differentiating
them allows userspace to make more informed decisions about what the
error means.

For example. radvd tries to join the all-routers group on every SIGHUP.
This fails, because it's already joined it, but this failure should be
ignored (rather than treated as a sign that the interface's multicast is
broken).

This puts us in line with OpenBSD, NetBSD and Linux.

Reviewed by:	donner
MFC after:	1 week
Sponsored by:	Rubicon Communications, LLC ("Netgate")
Differential Revision:	https://reviews.freebsd.org/D30111
2021-05-10 09:48:51 +02:00

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/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 2009 Bruce Simpson.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. 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.
*/
/*
* IPv6 multicast socket, group, and socket option processing module.
* Normative references: RFC 2292, RFC 3492, RFC 3542, RFC 3678, RFC 3810.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/ktr.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <sys/priv.h>
#include <sys/taskqueue.h>
#include <sys/tree.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <net/route/nhop.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/udp.h>
#include <netinet/in_var.h>
#include <netinet/ip_var.h>
#include <netinet/udp_var.h>
#include <netinet6/in6_fib.h>
#include <netinet6/in6_var.h>
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
#include <netinet6/ip6_var.h>
#include <netinet/in_pcb.h>
#include <netinet/tcp_var.h>
#include <netinet6/nd6.h>
#include <netinet6/mld6_var.h>
#include <netinet6/scope6_var.h>
#ifndef KTR_MLD
#define KTR_MLD KTR_INET6
#endif
#ifndef __SOCKUNION_DECLARED
union sockunion {
struct sockaddr_storage ss;
struct sockaddr sa;
struct sockaddr_dl sdl;
struct sockaddr_in6 sin6;
};
typedef union sockunion sockunion_t;
#define __SOCKUNION_DECLARED
#endif /* __SOCKUNION_DECLARED */
static MALLOC_DEFINE(M_IN6MFILTER, "in6_mfilter",
"IPv6 multicast PCB-layer source filter");
MALLOC_DEFINE(M_IP6MADDR, "in6_multi", "IPv6 multicast group");
static MALLOC_DEFINE(M_IP6MOPTS, "ip6_moptions", "IPv6 multicast options");
static MALLOC_DEFINE(M_IP6MSOURCE, "ip6_msource",
"IPv6 multicast MLD-layer source filter");
RB_GENERATE(ip6_msource_tree, ip6_msource, im6s_link, ip6_msource_cmp);
/*
* Locking:
* - Lock order is: Giant, IN6_MULTI_LOCK, INP_WLOCK,
* IN6_MULTI_LIST_LOCK, MLD_LOCK, IF_ADDR_LOCK.
* - The IF_ADDR_LOCK is implicitly taken by in6m_lookup() earlier, however
* it can be taken by code in net/if.c also.
* - ip6_moptions and in6_mfilter are covered by the INP_WLOCK.
*
* struct in6_multi is covered by IN6_MULTI_LOCK. There isn't strictly
* any need for in6_multi itself to be virtualized -- it is bound to an ifp
* anyway no matter what happens.
*/
struct mtx in6_multi_list_mtx;
MTX_SYSINIT(in6_multi_mtx, &in6_multi_list_mtx, "in6_multi_list_mtx", MTX_DEF);
struct mtx in6_multi_free_mtx;
MTX_SYSINIT(in6_multi_free_mtx, &in6_multi_free_mtx, "in6_multi_free_mtx", MTX_DEF);
struct sx in6_multi_sx;
SX_SYSINIT(in6_multi_sx, &in6_multi_sx, "in6_multi_sx");
static void im6f_commit(struct in6_mfilter *);
static int im6f_get_source(struct in6_mfilter *imf,
const struct sockaddr_in6 *psin,
struct in6_msource **);
static struct in6_msource *
im6f_graft(struct in6_mfilter *, const uint8_t,
const struct sockaddr_in6 *);
static void im6f_leave(struct in6_mfilter *);
static int im6f_prune(struct in6_mfilter *, const struct sockaddr_in6 *);
static void im6f_purge(struct in6_mfilter *);
static void im6f_rollback(struct in6_mfilter *);
static void im6f_reap(struct in6_mfilter *);
static struct in6_mfilter *
im6o_match_group(const struct ip6_moptions *,
const struct ifnet *, const struct sockaddr *);
static struct in6_msource *
im6o_match_source(struct in6_mfilter *, const struct sockaddr *);
static void im6s_merge(struct ip6_msource *ims,
const struct in6_msource *lims, const int rollback);
static int in6_getmulti(struct ifnet *, const struct in6_addr *,
struct in6_multi **);
static int in6_joingroup_locked(struct ifnet *, const struct in6_addr *,
struct in6_mfilter *, struct in6_multi **, int);
static int in6m_get_source(struct in6_multi *inm,
const struct in6_addr *addr, const int noalloc,
struct ip6_msource **pims);
#ifdef KTR
static int in6m_is_ifp_detached(const struct in6_multi *);
#endif
static int in6m_merge(struct in6_multi *, /*const*/ struct in6_mfilter *);
static void in6m_purge(struct in6_multi *);
static void in6m_reap(struct in6_multi *);
static struct ip6_moptions *
in6p_findmoptions(struct inpcb *);
static int in6p_get_source_filters(struct inpcb *, struct sockopt *);
static int in6p_join_group(struct inpcb *, struct sockopt *);
static int in6p_leave_group(struct inpcb *, struct sockopt *);
static struct ifnet *
in6p_lookup_mcast_ifp(const struct inpcb *,
const struct sockaddr_in6 *);
static int in6p_block_unblock_source(struct inpcb *, struct sockopt *);
static int in6p_set_multicast_if(struct inpcb *, struct sockopt *);
static int in6p_set_source_filters(struct inpcb *, struct sockopt *);
static int sysctl_ip6_mcast_filters(SYSCTL_HANDLER_ARGS);
SYSCTL_DECL(_net_inet6_ip6); /* XXX Not in any common header. */
static SYSCTL_NODE(_net_inet6_ip6, OID_AUTO, mcast,
CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
"IPv6 multicast");
static u_long in6_mcast_maxgrpsrc = IPV6_MAX_GROUP_SRC_FILTER;
SYSCTL_ULONG(_net_inet6_ip6_mcast, OID_AUTO, maxgrpsrc,
CTLFLAG_RWTUN, &in6_mcast_maxgrpsrc, 0,
"Max source filters per group");
static u_long in6_mcast_maxsocksrc = IPV6_MAX_SOCK_SRC_FILTER;
SYSCTL_ULONG(_net_inet6_ip6_mcast, OID_AUTO, maxsocksrc,
CTLFLAG_RWTUN, &in6_mcast_maxsocksrc, 0,
"Max source filters per socket");
/* TODO Virtualize this switch. */
int in6_mcast_loop = IPV6_DEFAULT_MULTICAST_LOOP;
SYSCTL_INT(_net_inet6_ip6_mcast, OID_AUTO, loop, CTLFLAG_RWTUN,
&in6_mcast_loop, 0, "Loopback multicast datagrams by default");
static SYSCTL_NODE(_net_inet6_ip6_mcast, OID_AUTO, filters,
CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_ip6_mcast_filters,
"Per-interface stack-wide source filters");
#ifdef KTR
/*
* Inline function which wraps assertions for a valid ifp.
* The ifnet layer will set the ifma's ifp pointer to NULL if the ifp
* is detached.
*/
static int __inline
in6m_is_ifp_detached(const struct in6_multi *inm)
{
struct ifnet *ifp;
KASSERT(inm->in6m_ifma != NULL, ("%s: no ifma", __func__));
ifp = inm->in6m_ifma->ifma_ifp;
if (ifp != NULL) {
/*
* Sanity check that network-layer notion of ifp is the
* same as that of link-layer.
*/
KASSERT(inm->in6m_ifp == ifp, ("%s: bad ifp", __func__));
}
return (ifp == NULL);
}
#endif
/*
* Initialize an in6_mfilter structure to a known state at t0, t1
* with an empty source filter list.
*/
static __inline void
im6f_init(struct in6_mfilter *imf, const int st0, const int st1)
{
memset(imf, 0, sizeof(struct in6_mfilter));
RB_INIT(&imf->im6f_sources);
imf->im6f_st[0] = st0;
imf->im6f_st[1] = st1;
}
struct in6_mfilter *
ip6_mfilter_alloc(const int mflags, const int st0, const int st1)
{
struct in6_mfilter *imf;
imf = malloc(sizeof(*imf), M_IN6MFILTER, mflags);
if (imf != NULL)
im6f_init(imf, st0, st1);
return (imf);
}
void
ip6_mfilter_free(struct in6_mfilter *imf)
{
im6f_purge(imf);
free(imf, M_IN6MFILTER);
}
/*
* Find an IPv6 multicast group entry for this ip6_moptions instance
* which matches the specified group, and optionally an interface.
* Return its index into the array, or -1 if not found.
*/
static struct in6_mfilter *
im6o_match_group(const struct ip6_moptions *imo, const struct ifnet *ifp,
const struct sockaddr *group)
{
const struct sockaddr_in6 *gsin6;
struct in6_mfilter *imf;
struct in6_multi *inm;
gsin6 = (const struct sockaddr_in6 *)group;
IP6_MFILTER_FOREACH(imf, &imo->im6o_head) {
inm = imf->im6f_in6m;
if (inm == NULL)
continue;
if ((ifp == NULL || (inm->in6m_ifp == ifp)) &&
IN6_ARE_ADDR_EQUAL(&inm->in6m_addr,
&gsin6->sin6_addr)) {
break;
}
}
return (imf);
}
/*
* Find an IPv6 multicast source entry for this imo which matches
* the given group index for this socket, and source address.
*
* XXX TODO: The scope ID, if present in src, is stripped before
* any comparison. We SHOULD enforce scope/zone checks where the source
* filter entry has a link scope.
*
* NOTE: This does not check if the entry is in-mode, merely if
* it exists, which may not be the desired behaviour.
*/
static struct in6_msource *
im6o_match_source(struct in6_mfilter *imf, const struct sockaddr *src)
{
struct ip6_msource find;
struct ip6_msource *ims;
const sockunion_t *psa;
KASSERT(src->sa_family == AF_INET6, ("%s: !AF_INET6", __func__));
psa = (const sockunion_t *)src;
find.im6s_addr = psa->sin6.sin6_addr;
in6_clearscope(&find.im6s_addr); /* XXX */
ims = RB_FIND(ip6_msource_tree, &imf->im6f_sources, &find);
return ((struct in6_msource *)ims);
}
/*
* Perform filtering for multicast datagrams on a socket by group and source.
*
* Returns 0 if a datagram should be allowed through, or various error codes
* if the socket was not a member of the group, or the source was muted, etc.
*/
int
im6o_mc_filter(const struct ip6_moptions *imo, const struct ifnet *ifp,
const struct sockaddr *group, const struct sockaddr *src)
{
struct in6_mfilter *imf;
struct in6_msource *ims;
int mode;
KASSERT(ifp != NULL, ("%s: null ifp", __func__));
imf = im6o_match_group(imo, ifp, group);
if (imf == NULL)
return (MCAST_NOTGMEMBER);
/*
* Check if the source was included in an (S,G) join.
* Allow reception on exclusive memberships by default,
* reject reception on inclusive memberships by default.
* Exclude source only if an in-mode exclude filter exists.
* Include source only if an in-mode include filter exists.
* NOTE: We are comparing group state here at MLD t1 (now)
* with socket-layer t0 (since last downcall).
*/
mode = imf->im6f_st[1];
ims = im6o_match_source(imf, src);
if ((ims == NULL && mode == MCAST_INCLUDE) ||
(ims != NULL && ims->im6sl_st[0] != mode))
return (MCAST_NOTSMEMBER);
return (MCAST_PASS);
}
/*
* Find and return a reference to an in6_multi record for (ifp, group),
* and bump its reference count.
* If one does not exist, try to allocate it, and update link-layer multicast
* filters on ifp to listen for group.
* Assumes the IN6_MULTI lock is held across the call.
* Return 0 if successful, otherwise return an appropriate error code.
*/
static int
in6_getmulti(struct ifnet *ifp, const struct in6_addr *group,
struct in6_multi **pinm)
{
struct epoch_tracker et;
struct sockaddr_in6 gsin6;
struct ifmultiaddr *ifma;
struct in6_multi *inm;
int error;
error = 0;
/*
* XXX: Accesses to ifma_protospec must be covered by IF_ADDR_LOCK;
* if_addmulti() takes this mutex itself, so we must drop and
* re-acquire around the call.
*/
IN6_MULTI_LOCK_ASSERT();
IN6_MULTI_LIST_LOCK();
IF_ADDR_WLOCK(ifp);
NET_EPOCH_ENTER(et);
inm = in6m_lookup_locked(ifp, group);
NET_EPOCH_EXIT(et);
if (inm != NULL) {
/*
* If we already joined this group, just bump the
* refcount and return it.
*/
KASSERT(inm->in6m_refcount >= 1,
("%s: bad refcount %d", __func__, inm->in6m_refcount));
in6m_acquire_locked(inm);
*pinm = inm;
goto out_locked;
}
memset(&gsin6, 0, sizeof(gsin6));
gsin6.sin6_family = AF_INET6;
gsin6.sin6_len = sizeof(struct sockaddr_in6);
gsin6.sin6_addr = *group;
/*
* Check if a link-layer group is already associated
* with this network-layer group on the given ifnet.
*/
IN6_MULTI_LIST_UNLOCK();
IF_ADDR_WUNLOCK(ifp);
error = if_addmulti(ifp, (struct sockaddr *)&gsin6, &ifma);
if (error != 0)
return (error);
IN6_MULTI_LIST_LOCK();
IF_ADDR_WLOCK(ifp);
/*
* If something other than netinet6 is occupying the link-layer
* group, print a meaningful error message and back out of
* the allocation.
* Otherwise, bump the refcount on the existing network-layer
* group association and return it.
*/
if (ifma->ifma_protospec != NULL) {
inm = (struct in6_multi *)ifma->ifma_protospec;
#ifdef INVARIANTS
KASSERT(ifma->ifma_addr != NULL, ("%s: no ifma_addr",
__func__));
KASSERT(ifma->ifma_addr->sa_family == AF_INET6,
("%s: ifma not AF_INET6", __func__));
KASSERT(inm != NULL, ("%s: no ifma_protospec", __func__));
if (inm->in6m_ifma != ifma || inm->in6m_ifp != ifp ||
!IN6_ARE_ADDR_EQUAL(&inm->in6m_addr, group))
panic("%s: ifma %p is inconsistent with %p (%p)",
__func__, ifma, inm, group);
#endif
in6m_acquire_locked(inm);
*pinm = inm;
goto out_locked;
}
IF_ADDR_WLOCK_ASSERT(ifp);
/*
* A new in6_multi record is needed; allocate and initialize it.
* We DO NOT perform an MLD join as the in6_ layer may need to
* push an initial source list down to MLD to support SSM.
*
* The initial source filter state is INCLUDE, {} as per the RFC.
* Pending state-changes per group are subject to a bounds check.
*/
inm = malloc(sizeof(*inm), M_IP6MADDR, M_NOWAIT | M_ZERO);
if (inm == NULL) {
IN6_MULTI_LIST_UNLOCK();
IF_ADDR_WUNLOCK(ifp);
if_delmulti_ifma(ifma);
return (ENOMEM);
}
inm->in6m_addr = *group;
inm->in6m_ifp = ifp;
inm->in6m_mli = MLD_IFINFO(ifp);
inm->in6m_ifma = ifma;
inm->in6m_refcount = 1;
inm->in6m_state = MLD_NOT_MEMBER;
mbufq_init(&inm->in6m_scq, MLD_MAX_STATE_CHANGES);
inm->in6m_st[0].iss_fmode = MCAST_UNDEFINED;
inm->in6m_st[1].iss_fmode = MCAST_UNDEFINED;
RB_INIT(&inm->in6m_srcs);
ifma->ifma_protospec = inm;
*pinm = inm;
out_locked:
IN6_MULTI_LIST_UNLOCK();
IF_ADDR_WUNLOCK(ifp);
return (error);
}
/*
* Drop a reference to an in6_multi record.
*
* If the refcount drops to 0, free the in6_multi record and
* delete the underlying link-layer membership.
*/
static void
in6m_release(struct in6_multi *inm)
{
struct ifmultiaddr *ifma;
struct ifnet *ifp;
CTR2(KTR_MLD, "%s: refcount is %d", __func__, inm->in6m_refcount);
MPASS(inm->in6m_refcount == 0);
CTR2(KTR_MLD, "%s: freeing inm %p", __func__, inm);
ifma = inm->in6m_ifma;
ifp = inm->in6m_ifp;
MPASS(ifma->ifma_llifma == NULL);
/* XXX this access is not covered by IF_ADDR_LOCK */
CTR2(KTR_MLD, "%s: purging ifma %p", __func__, ifma);
KASSERT(ifma->ifma_protospec == NULL,
("%s: ifma_protospec != NULL", __func__));
if (ifp == NULL)
ifp = ifma->ifma_ifp;
if (ifp != NULL) {
CURVNET_SET(ifp->if_vnet);
in6m_purge(inm);
free(inm, M_IP6MADDR);
if_delmulti_ifma_flags(ifma, 1);
CURVNET_RESTORE();
if_rele(ifp);
} else {
in6m_purge(inm);
free(inm, M_IP6MADDR);
if_delmulti_ifma_flags(ifma, 1);
}
}
/*
* Interface detach can happen in a taskqueue thread context, so we must use a
* dedicated thread to avoid deadlocks when draining in6m_release tasks.
*/
TASKQUEUE_DEFINE_THREAD(in6m_free);
static struct in6_multi_head in6m_free_list = SLIST_HEAD_INITIALIZER();
static void in6m_release_task(void *arg __unused, int pending __unused);
static struct task in6m_free_task = TASK_INITIALIZER(0, in6m_release_task, NULL);
void
in6m_release_list_deferred(struct in6_multi_head *inmh)
{
if (SLIST_EMPTY(inmh))
return;
mtx_lock(&in6_multi_free_mtx);
SLIST_CONCAT(&in6m_free_list, inmh, in6_multi, in6m_nrele);
mtx_unlock(&in6_multi_free_mtx);
taskqueue_enqueue(taskqueue_in6m_free, &in6m_free_task);
}
void
in6m_release_wait(void *arg __unused)
{
/*
* Make sure all pending multicast addresses are freed before
* the VNET or network device is destroyed:
*/
taskqueue_drain_all(taskqueue_in6m_free);
}
#ifdef VIMAGE
/* XXX-BZ FIXME, see D24914. */
VNET_SYSUNINIT(in6m_release_wait, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, in6m_release_wait, NULL);
#endif
void
in6m_disconnect_locked(struct in6_multi_head *inmh, struct in6_multi *inm)
{
struct ifnet *ifp;
struct ifaddr *ifa;
struct in6_ifaddr *ifa6;
struct in6_multi_mship *imm, *imm_tmp;
struct ifmultiaddr *ifma, *ll_ifma;
IN6_MULTI_LIST_LOCK_ASSERT();
ifp = inm->in6m_ifp;
if (ifp == NULL)
return; /* already called */
inm->in6m_ifp = NULL;
IF_ADDR_WLOCK_ASSERT(ifp);
ifma = inm->in6m_ifma;
if (ifma == NULL)
return;
if_ref(ifp);
if (ifma->ifma_flags & IFMA_F_ENQUEUED) {
CK_STAILQ_REMOVE(&ifp->if_multiaddrs, ifma, ifmultiaddr, ifma_link);
ifma->ifma_flags &= ~IFMA_F_ENQUEUED;
}
MCDPRINTF("removed ifma: %p from %s\n", ifma, ifp->if_xname);
if ((ll_ifma = ifma->ifma_llifma) != NULL) {
MPASS(ifma != ll_ifma);
ifma->ifma_llifma = NULL;
MPASS(ll_ifma->ifma_llifma == NULL);
MPASS(ll_ifma->ifma_ifp == ifp);
if (--ll_ifma->ifma_refcount == 0) {
if (ll_ifma->ifma_flags & IFMA_F_ENQUEUED) {
CK_STAILQ_REMOVE(&ifp->if_multiaddrs, ll_ifma, ifmultiaddr, ifma_link);
ll_ifma->ifma_flags &= ~IFMA_F_ENQUEUED;
}
MCDPRINTF("removed ll_ifma: %p from %s\n", ll_ifma, ifp->if_xname);
if_freemulti(ll_ifma);
}
}
CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
if (ifa->ifa_addr->sa_family != AF_INET6)
continue;
ifa6 = (void *)ifa;
LIST_FOREACH_SAFE(imm, &ifa6->ia6_memberships,
i6mm_chain, imm_tmp) {
if (inm == imm->i6mm_maddr) {
LIST_REMOVE(imm, i6mm_chain);
free(imm, M_IP6MADDR);
in6m_rele_locked(inmh, inm);
}
}
}
}
static void
in6m_release_task(void *arg __unused, int pending __unused)
{
struct in6_multi_head in6m_free_tmp;
struct in6_multi *inm, *tinm;
SLIST_INIT(&in6m_free_tmp);
mtx_lock(&in6_multi_free_mtx);
SLIST_CONCAT(&in6m_free_tmp, &in6m_free_list, in6_multi, in6m_nrele);
mtx_unlock(&in6_multi_free_mtx);
IN6_MULTI_LOCK();
SLIST_FOREACH_SAFE(inm, &in6m_free_tmp, in6m_nrele, tinm) {
SLIST_REMOVE_HEAD(&in6m_free_tmp, in6m_nrele);
in6m_release(inm);
}
IN6_MULTI_UNLOCK();
}
/*
* Clear recorded source entries for a group.
* Used by the MLD code. Caller must hold the IN6_MULTI lock.
* FIXME: Should reap.
*/
void
in6m_clear_recorded(struct in6_multi *inm)
{
struct ip6_msource *ims;
IN6_MULTI_LIST_LOCK_ASSERT();
RB_FOREACH(ims, ip6_msource_tree, &inm->in6m_srcs) {
if (ims->im6s_stp) {
ims->im6s_stp = 0;
--inm->in6m_st[1].iss_rec;
}
}
KASSERT(inm->in6m_st[1].iss_rec == 0,
("%s: iss_rec %d not 0", __func__, inm->in6m_st[1].iss_rec));
}
/*
* Record a source as pending for a Source-Group MLDv2 query.
* This lives here as it modifies the shared tree.
*
* inm is the group descriptor.
* naddr is the address of the source to record in network-byte order.
*
* If the net.inet6.mld.sgalloc sysctl is non-zero, we will
* lazy-allocate a source node in response to an SG query.
* Otherwise, no allocation is performed. This saves some memory
* with the trade-off that the source will not be reported to the
* router if joined in the window between the query response and
* the group actually being joined on the local host.
*
* VIMAGE: XXX: Currently the mld_sgalloc feature has been removed.
* This turns off the allocation of a recorded source entry if
* the group has not been joined.
*
* Return 0 if the source didn't exist or was already marked as recorded.
* Return 1 if the source was marked as recorded by this function.
* Return <0 if any error occurred (negated errno code).
*/
int
in6m_record_source(struct in6_multi *inm, const struct in6_addr *addr)
{
struct ip6_msource find;
struct ip6_msource *ims, *nims;
IN6_MULTI_LIST_LOCK_ASSERT();
find.im6s_addr = *addr;
ims = RB_FIND(ip6_msource_tree, &inm->in6m_srcs, &find);
if (ims && ims->im6s_stp)
return (0);
if (ims == NULL) {
if (inm->in6m_nsrc == in6_mcast_maxgrpsrc)
return (-ENOSPC);
nims = malloc(sizeof(struct ip6_msource), M_IP6MSOURCE,
M_NOWAIT | M_ZERO);
if (nims == NULL)
return (-ENOMEM);
nims->im6s_addr = find.im6s_addr;
RB_INSERT(ip6_msource_tree, &inm->in6m_srcs, nims);
++inm->in6m_nsrc;
ims = nims;
}
/*
* Mark the source as recorded and update the recorded
* source count.
*/
++ims->im6s_stp;
++inm->in6m_st[1].iss_rec;
return (1);
}
/*
* Return a pointer to an in6_msource owned by an in6_mfilter,
* given its source address.
* Lazy-allocate if needed. If this is a new entry its filter state is
* undefined at t0.
*
* imf is the filter set being modified.
* addr is the source address.
*
* SMPng: May be called with locks held; malloc must not block.
*/
static int
im6f_get_source(struct in6_mfilter *imf, const struct sockaddr_in6 *psin,
struct in6_msource **plims)
{
struct ip6_msource find;
struct ip6_msource *ims, *nims;
struct in6_msource *lims;
int error;
error = 0;
ims = NULL;
lims = NULL;
find.im6s_addr = psin->sin6_addr;
ims = RB_FIND(ip6_msource_tree, &imf->im6f_sources, &find);
lims = (struct in6_msource *)ims;
if (lims == NULL) {
if (imf->im6f_nsrc == in6_mcast_maxsocksrc)
return (ENOSPC);
nims = malloc(sizeof(struct in6_msource), M_IN6MFILTER,
M_NOWAIT | M_ZERO);
if (nims == NULL)
return (ENOMEM);
lims = (struct in6_msource *)nims;
lims->im6s_addr = find.im6s_addr;
lims->im6sl_st[0] = MCAST_UNDEFINED;
RB_INSERT(ip6_msource_tree, &imf->im6f_sources, nims);
++imf->im6f_nsrc;
}
*plims = lims;
return (error);
}
/*
* Graft a source entry into an existing socket-layer filter set,
* maintaining any required invariants and checking allocations.
*
* The source is marked as being in the new filter mode at t1.
*
* Return the pointer to the new node, otherwise return NULL.
*/
static struct in6_msource *
im6f_graft(struct in6_mfilter *imf, const uint8_t st1,
const struct sockaddr_in6 *psin)
{
struct ip6_msource *nims;
struct in6_msource *lims;
nims = malloc(sizeof(struct in6_msource), M_IN6MFILTER,
M_NOWAIT | M_ZERO);
if (nims == NULL)
return (NULL);
lims = (struct in6_msource *)nims;
lims->im6s_addr = psin->sin6_addr;
lims->im6sl_st[0] = MCAST_UNDEFINED;
lims->im6sl_st[1] = st1;
RB_INSERT(ip6_msource_tree, &imf->im6f_sources, nims);
++imf->im6f_nsrc;
return (lims);
}
/*
* Prune a source entry from an existing socket-layer filter set,
* maintaining any required invariants and checking allocations.
*
* The source is marked as being left at t1, it is not freed.
*
* Return 0 if no error occurred, otherwise return an errno value.
*/
static int
im6f_prune(struct in6_mfilter *imf, const struct sockaddr_in6 *psin)
{
struct ip6_msource find;
struct ip6_msource *ims;
struct in6_msource *lims;
find.im6s_addr = psin->sin6_addr;
ims = RB_FIND(ip6_msource_tree, &imf->im6f_sources, &find);
if (ims == NULL)
return (ENOENT);
lims = (struct in6_msource *)ims;
lims->im6sl_st[1] = MCAST_UNDEFINED;
return (0);
}
/*
* Revert socket-layer filter set deltas at t1 to t0 state.
*/
static void
im6f_rollback(struct in6_mfilter *imf)
{
struct ip6_msource *ims, *tims;
struct in6_msource *lims;
RB_FOREACH_SAFE(ims, ip6_msource_tree, &imf->im6f_sources, tims) {
lims = (struct in6_msource *)ims;
if (lims->im6sl_st[0] == lims->im6sl_st[1]) {
/* no change at t1 */
continue;
} else if (lims->im6sl_st[0] != MCAST_UNDEFINED) {
/* revert change to existing source at t1 */
lims->im6sl_st[1] = lims->im6sl_st[0];
} else {
/* revert source added t1 */
CTR2(KTR_MLD, "%s: free ims %p", __func__, ims);
RB_REMOVE(ip6_msource_tree, &imf->im6f_sources, ims);
free(ims, M_IN6MFILTER);
imf->im6f_nsrc--;
}
}
imf->im6f_st[1] = imf->im6f_st[0];
}
/*
* Mark socket-layer filter set as INCLUDE {} at t1.
*/
static void
im6f_leave(struct in6_mfilter *imf)
{
struct ip6_msource *ims;
struct in6_msource *lims;
RB_FOREACH(ims, ip6_msource_tree, &imf->im6f_sources) {
lims = (struct in6_msource *)ims;
lims->im6sl_st[1] = MCAST_UNDEFINED;
}
imf->im6f_st[1] = MCAST_INCLUDE;
}
/*
* Mark socket-layer filter set deltas as committed.
*/
static void
im6f_commit(struct in6_mfilter *imf)
{
struct ip6_msource *ims;
struct in6_msource *lims;
RB_FOREACH(ims, ip6_msource_tree, &imf->im6f_sources) {
lims = (struct in6_msource *)ims;
lims->im6sl_st[0] = lims->im6sl_st[1];
}
imf->im6f_st[0] = imf->im6f_st[1];
}
/*
* Reap unreferenced sources from socket-layer filter set.
*/
static void
im6f_reap(struct in6_mfilter *imf)
{
struct ip6_msource *ims, *tims;
struct in6_msource *lims;
RB_FOREACH_SAFE(ims, ip6_msource_tree, &imf->im6f_sources, tims) {
lims = (struct in6_msource *)ims;
if ((lims->im6sl_st[0] == MCAST_UNDEFINED) &&
(lims->im6sl_st[1] == MCAST_UNDEFINED)) {
CTR2(KTR_MLD, "%s: free lims %p", __func__, ims);
RB_REMOVE(ip6_msource_tree, &imf->im6f_sources, ims);
free(ims, M_IN6MFILTER);
imf->im6f_nsrc--;
}
}
}
/*
* Purge socket-layer filter set.
*/
static void
im6f_purge(struct in6_mfilter *imf)
{
struct ip6_msource *ims, *tims;
RB_FOREACH_SAFE(ims, ip6_msource_tree, &imf->im6f_sources, tims) {
CTR2(KTR_MLD, "%s: free ims %p", __func__, ims);
RB_REMOVE(ip6_msource_tree, &imf->im6f_sources, ims);
free(ims, M_IN6MFILTER);
imf->im6f_nsrc--;
}
imf->im6f_st[0] = imf->im6f_st[1] = MCAST_UNDEFINED;
KASSERT(RB_EMPTY(&imf->im6f_sources),
("%s: im6f_sources not empty", __func__));
}
/*
* Look up a source filter entry for a multicast group.
*
* inm is the group descriptor to work with.
* addr is the IPv6 address to look up.
* noalloc may be non-zero to suppress allocation of sources.
* *pims will be set to the address of the retrieved or allocated source.
*
* SMPng: NOTE: may be called with locks held.
* Return 0 if successful, otherwise return a non-zero error code.
*/
static int
in6m_get_source(struct in6_multi *inm, const struct in6_addr *addr,
const int noalloc, struct ip6_msource **pims)
{
struct ip6_msource find;
struct ip6_msource *ims, *nims;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
find.im6s_addr = *addr;
ims = RB_FIND(ip6_msource_tree, &inm->in6m_srcs, &find);
if (ims == NULL && !noalloc) {
if (inm->in6m_nsrc == in6_mcast_maxgrpsrc)
return (ENOSPC);
nims = malloc(sizeof(struct ip6_msource), M_IP6MSOURCE,
M_NOWAIT | M_ZERO);
if (nims == NULL)
return (ENOMEM);
nims->im6s_addr = *addr;
RB_INSERT(ip6_msource_tree, &inm->in6m_srcs, nims);
++inm->in6m_nsrc;
ims = nims;
CTR3(KTR_MLD, "%s: allocated %s as %p", __func__,
ip6_sprintf(ip6tbuf, addr), ims);
}
*pims = ims;
return (0);
}
/*
* Merge socket-layer source into MLD-layer source.
* If rollback is non-zero, perform the inverse of the merge.
*/
static void
im6s_merge(struct ip6_msource *ims, const struct in6_msource *lims,
const int rollback)
{
int n = rollback ? -1 : 1;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
ip6_sprintf(ip6tbuf, &lims->im6s_addr);
#endif
if (lims->im6sl_st[0] == MCAST_EXCLUDE) {
CTR3(KTR_MLD, "%s: t1 ex -= %d on %s", __func__, n, ip6tbuf);
ims->im6s_st[1].ex -= n;
} else if (lims->im6sl_st[0] == MCAST_INCLUDE) {
CTR3(KTR_MLD, "%s: t1 in -= %d on %s", __func__, n, ip6tbuf);
ims->im6s_st[1].in -= n;
}
if (lims->im6sl_st[1] == MCAST_EXCLUDE) {
CTR3(KTR_MLD, "%s: t1 ex += %d on %s", __func__, n, ip6tbuf);
ims->im6s_st[1].ex += n;
} else if (lims->im6sl_st[1] == MCAST_INCLUDE) {
CTR3(KTR_MLD, "%s: t1 in += %d on %s", __func__, n, ip6tbuf);
ims->im6s_st[1].in += n;
}
}
/*
* Atomically update the global in6_multi state, when a membership's
* filter list is being updated in any way.
*
* imf is the per-inpcb-membership group filter pointer.
* A fake imf may be passed for in-kernel consumers.
*
* XXX This is a candidate for a set-symmetric-difference style loop
* which would eliminate the repeated lookup from root of ims nodes,
* as they share the same key space.
*
* If any error occurred this function will back out of refcounts
* and return a non-zero value.
*/
static int
in6m_merge(struct in6_multi *inm, /*const*/ struct in6_mfilter *imf)
{
struct ip6_msource *ims, *nims;
struct in6_msource *lims;
int schanged, error;
int nsrc0, nsrc1;
schanged = 0;
error = 0;
nsrc1 = nsrc0 = 0;
IN6_MULTI_LIST_LOCK_ASSERT();
/*
* Update the source filters first, as this may fail.
* Maintain count of in-mode filters at t0, t1. These are
* used to work out if we transition into ASM mode or not.
* Maintain a count of source filters whose state was
* actually modified by this operation.
*/
RB_FOREACH(ims, ip6_msource_tree, &imf->im6f_sources) {
lims = (struct in6_msource *)ims;
if (lims->im6sl_st[0] == imf->im6f_st[0]) nsrc0++;
if (lims->im6sl_st[1] == imf->im6f_st[1]) nsrc1++;
if (lims->im6sl_st[0] == lims->im6sl_st[1]) continue;
error = in6m_get_source(inm, &lims->im6s_addr, 0, &nims);
++schanged;
if (error)
break;
im6s_merge(nims, lims, 0);
}
if (error) {
struct ip6_msource *bims;
RB_FOREACH_REVERSE_FROM(ims, ip6_msource_tree, nims) {
lims = (struct in6_msource *)ims;
if (lims->im6sl_st[0] == lims->im6sl_st[1])
continue;
(void)in6m_get_source(inm, &lims->im6s_addr, 1, &bims);
if (bims == NULL)
continue;
im6s_merge(bims, lims, 1);
}
goto out_reap;
}
CTR3(KTR_MLD, "%s: imf filters in-mode: %d at t0, %d at t1",
__func__, nsrc0, nsrc1);
/* Handle transition between INCLUDE {n} and INCLUDE {} on socket. */
if (imf->im6f_st[0] == imf->im6f_st[1] &&
imf->im6f_st[1] == MCAST_INCLUDE) {
if (nsrc1 == 0) {
CTR1(KTR_MLD, "%s: --in on inm at t1", __func__);
--inm->in6m_st[1].iss_in;
}
}
/* Handle filter mode transition on socket. */
if (imf->im6f_st[0] != imf->im6f_st[1]) {
CTR3(KTR_MLD, "%s: imf transition %d to %d",
__func__, imf->im6f_st[0], imf->im6f_st[1]);
if (imf->im6f_st[0] == MCAST_EXCLUDE) {
CTR1(KTR_MLD, "%s: --ex on inm at t1", __func__);
--inm->in6m_st[1].iss_ex;
} else if (imf->im6f_st[0] == MCAST_INCLUDE) {
CTR1(KTR_MLD, "%s: --in on inm at t1", __func__);
--inm->in6m_st[1].iss_in;
}
if (imf->im6f_st[1] == MCAST_EXCLUDE) {
CTR1(KTR_MLD, "%s: ex++ on inm at t1", __func__);
inm->in6m_st[1].iss_ex++;
} else if (imf->im6f_st[1] == MCAST_INCLUDE && nsrc1 > 0) {
CTR1(KTR_MLD, "%s: in++ on inm at t1", __func__);
inm->in6m_st[1].iss_in++;
}
}
/*
* Track inm filter state in terms of listener counts.
* If there are any exclusive listeners, stack-wide
* membership is exclusive.
* Otherwise, if only inclusive listeners, stack-wide is inclusive.
* If no listeners remain, state is undefined at t1,
* and the MLD lifecycle for this group should finish.
*/
if (inm->in6m_st[1].iss_ex > 0) {
CTR1(KTR_MLD, "%s: transition to EX", __func__);
inm->in6m_st[1].iss_fmode = MCAST_EXCLUDE;
} else if (inm->in6m_st[1].iss_in > 0) {
CTR1(KTR_MLD, "%s: transition to IN", __func__);
inm->in6m_st[1].iss_fmode = MCAST_INCLUDE;
} else {
CTR1(KTR_MLD, "%s: transition to UNDEF", __func__);
inm->in6m_st[1].iss_fmode = MCAST_UNDEFINED;
}
/* Decrement ASM listener count on transition out of ASM mode. */
if (imf->im6f_st[0] == MCAST_EXCLUDE && nsrc0 == 0) {
if ((imf->im6f_st[1] != MCAST_EXCLUDE) ||
(imf->im6f_st[1] == MCAST_EXCLUDE && nsrc1 > 0)) {
CTR1(KTR_MLD, "%s: --asm on inm at t1", __func__);
--inm->in6m_st[1].iss_asm;
}
}
/* Increment ASM listener count on transition to ASM mode. */
if (imf->im6f_st[1] == MCAST_EXCLUDE && nsrc1 == 0) {
CTR1(KTR_MLD, "%s: asm++ on inm at t1", __func__);
inm->in6m_st[1].iss_asm++;
}
CTR3(KTR_MLD, "%s: merged imf %p to inm %p", __func__, imf, inm);
in6m_print(inm);
out_reap:
if (schanged > 0) {
CTR1(KTR_MLD, "%s: sources changed; reaping", __func__);
in6m_reap(inm);
}
return (error);
}
/*
* Mark an in6_multi's filter set deltas as committed.
* Called by MLD after a state change has been enqueued.
*/
void
in6m_commit(struct in6_multi *inm)
{
struct ip6_msource *ims;
CTR2(KTR_MLD, "%s: commit inm %p", __func__, inm);
CTR1(KTR_MLD, "%s: pre commit:", __func__);
in6m_print(inm);
RB_FOREACH(ims, ip6_msource_tree, &inm->in6m_srcs) {
ims->im6s_st[0] = ims->im6s_st[1];
}
inm->in6m_st[0] = inm->in6m_st[1];
}
/*
* Reap unreferenced nodes from an in6_multi's filter set.
*/
static void
in6m_reap(struct in6_multi *inm)
{
struct ip6_msource *ims, *tims;
RB_FOREACH_SAFE(ims, ip6_msource_tree, &inm->in6m_srcs, tims) {
if (ims->im6s_st[0].ex > 0 || ims->im6s_st[0].in > 0 ||
ims->im6s_st[1].ex > 0 || ims->im6s_st[1].in > 0 ||
ims->im6s_stp != 0)
continue;
CTR2(KTR_MLD, "%s: free ims %p", __func__, ims);
RB_REMOVE(ip6_msource_tree, &inm->in6m_srcs, ims);
free(ims, M_IP6MSOURCE);
inm->in6m_nsrc--;
}
}
/*
* Purge all source nodes from an in6_multi's filter set.
*/
static void
in6m_purge(struct in6_multi *inm)
{
struct ip6_msource *ims, *tims;
RB_FOREACH_SAFE(ims, ip6_msource_tree, &inm->in6m_srcs, tims) {
CTR2(KTR_MLD, "%s: free ims %p", __func__, ims);
RB_REMOVE(ip6_msource_tree, &inm->in6m_srcs, ims);
free(ims, M_IP6MSOURCE);
inm->in6m_nsrc--;
}
/* Free state-change requests that might be queued. */
mbufq_drain(&inm->in6m_scq);
}
/*
* Join a multicast address w/o sources.
* KAME compatibility entry point.
*
* SMPng: Assume no mc locks held by caller.
*/
int
in6_joingroup(struct ifnet *ifp, const struct in6_addr *mcaddr,
/*const*/ struct in6_mfilter *imf, struct in6_multi **pinm,
const int delay)
{
int error;
IN6_MULTI_LOCK();
error = in6_joingroup_locked(ifp, mcaddr, NULL, pinm, delay);
IN6_MULTI_UNLOCK();
return (error);
}
/*
* Join a multicast group; real entry point.
*
* Only preserves atomicity at inm level.
* NOTE: imf argument cannot be const due to sys/tree.h limitations.
*
* If the MLD downcall fails, the group is not joined, and an error
* code is returned.
*/
static int
in6_joingroup_locked(struct ifnet *ifp, const struct in6_addr *mcaddr,
/*const*/ struct in6_mfilter *imf, struct in6_multi **pinm,
const int delay)
{
struct in6_multi_head inmh;
struct in6_mfilter timf;
struct in6_multi *inm;
struct ifmultiaddr *ifma;
int error;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
/*
* Sanity: Check scope zone ID was set for ifp, if and
* only if group is scoped to an interface.
*/
KASSERT(IN6_IS_ADDR_MULTICAST(mcaddr),
("%s: not a multicast address", __func__));
if (IN6_IS_ADDR_MC_LINKLOCAL(mcaddr) ||
IN6_IS_ADDR_MC_INTFACELOCAL(mcaddr)) {
KASSERT(mcaddr->s6_addr16[1] != 0,
("%s: scope zone ID not set", __func__));
}
IN6_MULTI_LOCK_ASSERT();
IN6_MULTI_LIST_UNLOCK_ASSERT();
CTR4(KTR_MLD, "%s: join %s on %p(%s))", __func__,
ip6_sprintf(ip6tbuf, mcaddr), ifp, if_name(ifp));
error = 0;
inm = NULL;
/*
* If no imf was specified (i.e. kernel consumer),
* fake one up and assume it is an ASM join.
*/
if (imf == NULL) {
im6f_init(&timf, MCAST_UNDEFINED, MCAST_EXCLUDE);
imf = &timf;
}
error = in6_getmulti(ifp, mcaddr, &inm);
if (error) {
CTR1(KTR_MLD, "%s: in6_getmulti() failure", __func__);
return (error);
}
IN6_MULTI_LIST_LOCK();
CTR1(KTR_MLD, "%s: merge inm state", __func__);
error = in6m_merge(inm, imf);
if (error) {
CTR1(KTR_MLD, "%s: failed to merge inm state", __func__);
goto out_in6m_release;
}
CTR1(KTR_MLD, "%s: doing mld downcall", __func__);
error = mld_change_state(inm, delay);
if (error) {
CTR1(KTR_MLD, "%s: failed to update source", __func__);
goto out_in6m_release;
}
out_in6m_release:
SLIST_INIT(&inmh);
if (error) {
struct epoch_tracker et;
CTR2(KTR_MLD, "%s: dropping ref on %p", __func__, inm);
IF_ADDR_WLOCK(ifp);
NET_EPOCH_ENTER(et);
CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
if (ifma->ifma_protospec == inm) {
ifma->ifma_protospec = NULL;
break;
}
}
in6m_disconnect_locked(&inmh, inm);
in6m_rele_locked(&inmh, inm);
NET_EPOCH_EXIT(et);
IF_ADDR_WUNLOCK(ifp);
} else {
*pinm = inm;
}
IN6_MULTI_LIST_UNLOCK();
in6m_release_list_deferred(&inmh);
return (error);
}
/*
* Leave a multicast group; unlocked entry point.
*/
int
in6_leavegroup(struct in6_multi *inm, /*const*/ struct in6_mfilter *imf)
{
int error;
IN6_MULTI_LOCK();
error = in6_leavegroup_locked(inm, imf);
IN6_MULTI_UNLOCK();
return (error);
}
/*
* Leave a multicast group; real entry point.
* All source filters will be expunged.
*
* Only preserves atomicity at inm level.
*
* Holding the write lock for the INP which contains imf
* is highly advisable. We can't assert for it as imf does not
* contain a back-pointer to the owning inp.
*
* Note: This is not the same as in6m_release(*) as this function also
* makes a state change downcall into MLD.
*/
int
in6_leavegroup_locked(struct in6_multi *inm, /*const*/ struct in6_mfilter *imf)
{
struct in6_multi_head inmh;
struct in6_mfilter timf;
struct ifnet *ifp;
int error;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
error = 0;
IN6_MULTI_LOCK_ASSERT();
CTR5(KTR_MLD, "%s: leave inm %p, %s/%s, imf %p", __func__,
inm, ip6_sprintf(ip6tbuf, &inm->in6m_addr),
(in6m_is_ifp_detached(inm) ? "null" : if_name(inm->in6m_ifp)),
imf);
/*
* If no imf was specified (i.e. kernel consumer),
* fake one up and assume it is an ASM join.
*/
if (imf == NULL) {
im6f_init(&timf, MCAST_EXCLUDE, MCAST_UNDEFINED);
imf = &timf;
}
/*
* Begin state merge transaction at MLD layer.
*
* As this particular invocation should not cause any memory
* to be allocated, and there is no opportunity to roll back
* the transaction, it MUST NOT fail.
*/
ifp = inm->in6m_ifp;
IN6_MULTI_LIST_LOCK();
CTR1(KTR_MLD, "%s: merge inm state", __func__);
error = in6m_merge(inm, imf);
KASSERT(error == 0, ("%s: failed to merge inm state", __func__));
CTR1(KTR_MLD, "%s: doing mld downcall", __func__);
error = 0;
if (ifp)
error = mld_change_state(inm, 0);
if (error)
CTR1(KTR_MLD, "%s: failed mld downcall", __func__);
CTR2(KTR_MLD, "%s: dropping ref on %p", __func__, inm);
if (ifp)
IF_ADDR_WLOCK(ifp);
SLIST_INIT(&inmh);
if (inm->in6m_refcount == 1)
in6m_disconnect_locked(&inmh, inm);
in6m_rele_locked(&inmh, inm);
if (ifp)
IF_ADDR_WUNLOCK(ifp);
IN6_MULTI_LIST_UNLOCK();
in6m_release_list_deferred(&inmh);
return (error);
}
/*
* Block or unblock an ASM multicast source on an inpcb.
* This implements the delta-based API described in RFC 3678.
*
* The delta-based API applies only to exclusive-mode memberships.
* An MLD downcall will be performed.
*
* SMPng: NOTE: Must take Giant as a join may create a new ifma.
*
* Return 0 if successful, otherwise return an appropriate error code.
*/
static int
in6p_block_unblock_source(struct inpcb *inp, struct sockopt *sopt)
{
struct group_source_req gsr;
sockunion_t *gsa, *ssa;
struct ifnet *ifp;
struct in6_mfilter *imf;
struct ip6_moptions *imo;
struct in6_msource *ims;
struct in6_multi *inm;
uint16_t fmode;
int error, doblock;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
ifp = NULL;
error = 0;
doblock = 0;
memset(&gsr, 0, sizeof(struct group_source_req));
gsa = (sockunion_t *)&gsr.gsr_group;
ssa = (sockunion_t *)&gsr.gsr_source;
switch (sopt->sopt_name) {
case MCAST_BLOCK_SOURCE:
case MCAST_UNBLOCK_SOURCE:
error = sooptcopyin(sopt, &gsr,
sizeof(struct group_source_req),
sizeof(struct group_source_req));
if (error)
return (error);
if (gsa->sin6.sin6_family != AF_INET6 ||
gsa->sin6.sin6_len != sizeof(struct sockaddr_in6))
return (EINVAL);
if (ssa->sin6.sin6_family != AF_INET6 ||
ssa->sin6.sin6_len != sizeof(struct sockaddr_in6))
return (EINVAL);
if (gsr.gsr_interface == 0 || V_if_index < gsr.gsr_interface)
return (EADDRNOTAVAIL);
ifp = ifnet_byindex(gsr.gsr_interface);
if (sopt->sopt_name == MCAST_BLOCK_SOURCE)
doblock = 1;
break;
default:
CTR2(KTR_MLD, "%s: unknown sopt_name %d",
__func__, sopt->sopt_name);
return (EOPNOTSUPP);
break;
}
if (!IN6_IS_ADDR_MULTICAST(&gsa->sin6.sin6_addr))
return (EINVAL);
(void)in6_setscope(&gsa->sin6.sin6_addr, ifp, NULL);
/*
* Check if we are actually a member of this group.
*/
imo = in6p_findmoptions(inp);
imf = im6o_match_group(imo, ifp, &gsa->sa);
if (imf == NULL) {
error = EADDRNOTAVAIL;
goto out_in6p_locked;
}
inm = imf->im6f_in6m;
/*
* Attempting to use the delta-based API on an
* non exclusive-mode membership is an error.
*/
fmode = imf->im6f_st[0];
if (fmode != MCAST_EXCLUDE) {
error = EINVAL;
goto out_in6p_locked;
}
/*
* Deal with error cases up-front:
* Asked to block, but already blocked; or
* Asked to unblock, but nothing to unblock.
* If adding a new block entry, allocate it.
*/
ims = im6o_match_source(imf, &ssa->sa);
if ((ims != NULL && doblock) || (ims == NULL && !doblock)) {
CTR3(KTR_MLD, "%s: source %s %spresent", __func__,
ip6_sprintf(ip6tbuf, &ssa->sin6.sin6_addr),
doblock ? "" : "not ");
error = EADDRNOTAVAIL;
goto out_in6p_locked;
}
INP_WLOCK_ASSERT(inp);
/*
* Begin state merge transaction at socket layer.
*/
if (doblock) {
CTR2(KTR_MLD, "%s: %s source", __func__, "block");
ims = im6f_graft(imf, fmode, &ssa->sin6);
if (ims == NULL)
error = ENOMEM;
} else {
CTR2(KTR_MLD, "%s: %s source", __func__, "allow");
error = im6f_prune(imf, &ssa->sin6);
}
if (error) {
CTR1(KTR_MLD, "%s: merge imf state failed", __func__);
goto out_im6f_rollback;
}
/*
* Begin state merge transaction at MLD layer.
*/
IN6_MULTI_LIST_LOCK();
CTR1(KTR_MLD, "%s: merge inm state", __func__);
error = in6m_merge(inm, imf);
if (error)
CTR1(KTR_MLD, "%s: failed to merge inm state", __func__);
else {
CTR1(KTR_MLD, "%s: doing mld downcall", __func__);
error = mld_change_state(inm, 0);
if (error)
CTR1(KTR_MLD, "%s: failed mld downcall", __func__);
}
IN6_MULTI_LIST_UNLOCK();
out_im6f_rollback:
if (error)
im6f_rollback(imf);
else
im6f_commit(imf);
im6f_reap(imf);
out_in6p_locked:
INP_WUNLOCK(inp);
return (error);
}
/*
* Given an inpcb, return its multicast options structure pointer. Accepts
* an unlocked inpcb pointer, but will return it locked. May sleep.
*
* SMPng: NOTE: Potentially calls malloc(M_WAITOK) with Giant held.
* SMPng: NOTE: Returns with the INP write lock held.
*/
static struct ip6_moptions *
in6p_findmoptions(struct inpcb *inp)
{
struct ip6_moptions *imo;
INP_WLOCK(inp);
if (inp->in6p_moptions != NULL)
return (inp->in6p_moptions);
INP_WUNLOCK(inp);
imo = malloc(sizeof(*imo), M_IP6MOPTS, M_WAITOK);
imo->im6o_multicast_ifp = NULL;
imo->im6o_multicast_hlim = V_ip6_defmcasthlim;
imo->im6o_multicast_loop = in6_mcast_loop;
STAILQ_INIT(&imo->im6o_head);
INP_WLOCK(inp);
if (inp->in6p_moptions != NULL) {
free(imo, M_IP6MOPTS);
return (inp->in6p_moptions);
}
inp->in6p_moptions = imo;
return (imo);
}
/*
* Discard the IPv6 multicast options (and source filters).
*
* SMPng: NOTE: assumes INP write lock is held.
*
* XXX can all be safely deferred to epoch_call
*
*/
static void
inp_gcmoptions(struct ip6_moptions *imo)
{
struct in6_mfilter *imf;
struct in6_multi *inm;
struct ifnet *ifp;
while ((imf = ip6_mfilter_first(&imo->im6o_head)) != NULL) {
ip6_mfilter_remove(&imo->im6o_head, imf);
im6f_leave(imf);
if ((inm = imf->im6f_in6m) != NULL) {
if ((ifp = inm->in6m_ifp) != NULL) {
CURVNET_SET(ifp->if_vnet);
(void)in6_leavegroup(inm, imf);
CURVNET_RESTORE();
} else {
(void)in6_leavegroup(inm, imf);
}
}
ip6_mfilter_free(imf);
}
free(imo, M_IP6MOPTS);
}
void
ip6_freemoptions(struct ip6_moptions *imo)
{
if (imo == NULL)
return;
inp_gcmoptions(imo);
}
/*
* Atomically get source filters on a socket for an IPv6 multicast group.
* Called with INP lock held; returns with lock released.
*/
static int
in6p_get_source_filters(struct inpcb *inp, struct sockopt *sopt)
{
struct __msfilterreq msfr;
sockunion_t *gsa;
struct ifnet *ifp;
struct ip6_moptions *imo;
struct in6_mfilter *imf;
struct ip6_msource *ims;
struct in6_msource *lims;
struct sockaddr_in6 *psin;
struct sockaddr_storage *ptss;
struct sockaddr_storage *tss;
int error;
size_t nsrcs, ncsrcs;
INP_WLOCK_ASSERT(inp);
imo = inp->in6p_moptions;
KASSERT(imo != NULL, ("%s: null ip6_moptions", __func__));
INP_WUNLOCK(inp);
error = sooptcopyin(sopt, &msfr, sizeof(struct __msfilterreq),
sizeof(struct __msfilterreq));
if (error)
return (error);
if (msfr.msfr_group.ss_family != AF_INET6 ||
msfr.msfr_group.ss_len != sizeof(struct sockaddr_in6))
return (EINVAL);
gsa = (sockunion_t *)&msfr.msfr_group;
if (!IN6_IS_ADDR_MULTICAST(&gsa->sin6.sin6_addr))
return (EINVAL);
if (msfr.msfr_ifindex == 0 || V_if_index < msfr.msfr_ifindex)
return (EADDRNOTAVAIL);
ifp = ifnet_byindex(msfr.msfr_ifindex);
if (ifp == NULL)
return (EADDRNOTAVAIL);
(void)in6_setscope(&gsa->sin6.sin6_addr, ifp, NULL);
INP_WLOCK(inp);
/*
* Lookup group on the socket.
*/
imf = im6o_match_group(imo, ifp, &gsa->sa);
if (imf == NULL) {
INP_WUNLOCK(inp);
return (EADDRNOTAVAIL);
}
/*
* Ignore memberships which are in limbo.
*/
if (imf->im6f_st[1] == MCAST_UNDEFINED) {
INP_WUNLOCK(inp);
return (EAGAIN);
}
msfr.msfr_fmode = imf->im6f_st[1];
/*
* If the user specified a buffer, copy out the source filter
* entries to userland gracefully.
* We only copy out the number of entries which userland
* has asked for, but we always tell userland how big the
* buffer really needs to be.
*/
if (msfr.msfr_nsrcs > in6_mcast_maxsocksrc)
msfr.msfr_nsrcs = in6_mcast_maxsocksrc;
tss = NULL;
if (msfr.msfr_srcs != NULL && msfr.msfr_nsrcs > 0) {
tss = malloc(sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs,
M_TEMP, M_NOWAIT | M_ZERO);
if (tss == NULL) {
INP_WUNLOCK(inp);
return (ENOBUFS);
}
}
/*
* Count number of sources in-mode at t0.
* If buffer space exists and remains, copy out source entries.
*/
nsrcs = msfr.msfr_nsrcs;
ncsrcs = 0;
ptss = tss;
RB_FOREACH(ims, ip6_msource_tree, &imf->im6f_sources) {
lims = (struct in6_msource *)ims;
if (lims->im6sl_st[0] == MCAST_UNDEFINED ||
lims->im6sl_st[0] != imf->im6f_st[0])
continue;
++ncsrcs;
if (tss != NULL && nsrcs > 0) {
psin = (struct sockaddr_in6 *)ptss;
psin->sin6_family = AF_INET6;
psin->sin6_len = sizeof(struct sockaddr_in6);
psin->sin6_addr = lims->im6s_addr;
psin->sin6_port = 0;
--nsrcs;
++ptss;
}
}
INP_WUNLOCK(inp);
if (tss != NULL) {
error = copyout(tss, msfr.msfr_srcs,
sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs);
free(tss, M_TEMP);
if (error)
return (error);
}
msfr.msfr_nsrcs = ncsrcs;
error = sooptcopyout(sopt, &msfr, sizeof(struct __msfilterreq));
return (error);
}
/*
* Return the IP multicast options in response to user getsockopt().
*/
int
ip6_getmoptions(struct inpcb *inp, struct sockopt *sopt)
{
struct ip6_moptions *im6o;
int error;
u_int optval;
INP_WLOCK(inp);
im6o = inp->in6p_moptions;
/*
* If socket is neither of type SOCK_RAW or SOCK_DGRAM,
* or is a divert socket, reject it.
*/
if (inp->inp_socket->so_proto->pr_protocol == IPPROTO_DIVERT ||
(inp->inp_socket->so_proto->pr_type != SOCK_RAW &&
inp->inp_socket->so_proto->pr_type != SOCK_DGRAM)) {
INP_WUNLOCK(inp);
return (EOPNOTSUPP);
}
error = 0;
switch (sopt->sopt_name) {
case IPV6_MULTICAST_IF:
if (im6o == NULL || im6o->im6o_multicast_ifp == NULL) {
optval = 0;
} else {
optval = im6o->im6o_multicast_ifp->if_index;
}
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &optval, sizeof(u_int));
break;
case IPV6_MULTICAST_HOPS:
if (im6o == NULL)
optval = V_ip6_defmcasthlim;
else
optval = im6o->im6o_multicast_hlim;
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &optval, sizeof(u_int));
break;
case IPV6_MULTICAST_LOOP:
if (im6o == NULL)
optval = in6_mcast_loop; /* XXX VIMAGE */
else
optval = im6o->im6o_multicast_loop;
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &optval, sizeof(u_int));
break;
case IPV6_MSFILTER:
if (im6o == NULL) {
error = EADDRNOTAVAIL;
INP_WUNLOCK(inp);
} else {
error = in6p_get_source_filters(inp, sopt);
}
break;
default:
INP_WUNLOCK(inp);
error = ENOPROTOOPT;
break;
}
INP_UNLOCK_ASSERT(inp);
return (error);
}
/*
* Look up the ifnet to use for a multicast group membership,
* given the address of an IPv6 group.
*
* This routine exists to support legacy IPv6 multicast applications.
*
* Use the socket's current FIB number for any required FIB lookup. Look up the
* group address in the unicast FIB, and use its ifp; usually, this points to
* the default next-hop. If the FIB lookup fails, return NULL.
*
* FUTURE: Support multiple forwarding tables for IPv6.
*
* Returns NULL if no ifp could be found.
*/
static struct ifnet *
in6p_lookup_mcast_ifp(const struct inpcb *inp, const struct sockaddr_in6 *gsin6)
{
struct nhop_object *nh;
struct in6_addr dst;
uint32_t scopeid;
uint32_t fibnum;
KASSERT(gsin6->sin6_family == AF_INET6,
("%s: not AF_INET6 group", __func__));
in6_splitscope(&gsin6->sin6_addr, &dst, &scopeid);
fibnum = inp->inp_inc.inc_fibnum;
nh = fib6_lookup(fibnum, &dst, scopeid, 0, 0);
return (nh ? nh->nh_ifp : NULL);
}
/*
* Join an IPv6 multicast group, possibly with a source.
*
* FIXME: The KAME use of the unspecified address (::)
* to join *all* multicast groups is currently unsupported.
*/
static int
in6p_join_group(struct inpcb *inp, struct sockopt *sopt)
{
struct in6_multi_head inmh;
struct group_source_req gsr;
sockunion_t *gsa, *ssa;
struct ifnet *ifp;
struct in6_mfilter *imf;
struct ip6_moptions *imo;
struct in6_multi *inm;
struct in6_msource *lims;
int error, is_new;
SLIST_INIT(&inmh);
ifp = NULL;
lims = NULL;
error = 0;
memset(&gsr, 0, sizeof(struct group_source_req));
gsa = (sockunion_t *)&gsr.gsr_group;
gsa->ss.ss_family = AF_UNSPEC;
ssa = (sockunion_t *)&gsr.gsr_source;
ssa->ss.ss_family = AF_UNSPEC;
/*
* Chew everything into struct group_source_req.
* Overwrite the port field if present, as the sockaddr
* being copied in may be matched with a binary comparison.
* Ignore passed-in scope ID.
*/
switch (sopt->sopt_name) {
case IPV6_JOIN_GROUP: {
struct ipv6_mreq mreq;
error = sooptcopyin(sopt, &mreq, sizeof(struct ipv6_mreq),
sizeof(struct ipv6_mreq));
if (error)
return (error);
gsa->sin6.sin6_family = AF_INET6;
gsa->sin6.sin6_len = sizeof(struct sockaddr_in6);
gsa->sin6.sin6_addr = mreq.ipv6mr_multiaddr;
if (mreq.ipv6mr_interface == 0) {
ifp = in6p_lookup_mcast_ifp(inp, &gsa->sin6);
} else {
if (V_if_index < mreq.ipv6mr_interface)
return (EADDRNOTAVAIL);
ifp = ifnet_byindex(mreq.ipv6mr_interface);
}
CTR3(KTR_MLD, "%s: ipv6mr_interface = %d, ifp = %p",
__func__, mreq.ipv6mr_interface, ifp);
} break;
case MCAST_JOIN_GROUP:
case MCAST_JOIN_SOURCE_GROUP:
if (sopt->sopt_name == MCAST_JOIN_GROUP) {
error = sooptcopyin(sopt, &gsr,
sizeof(struct group_req),
sizeof(struct group_req));
} else if (sopt->sopt_name == MCAST_JOIN_SOURCE_GROUP) {
error = sooptcopyin(sopt, &gsr,
sizeof(struct group_source_req),
sizeof(struct group_source_req));
}
if (error)
return (error);
if (gsa->sin6.sin6_family != AF_INET6 ||
gsa->sin6.sin6_len != sizeof(struct sockaddr_in6))
return (EINVAL);
if (sopt->sopt_name == MCAST_JOIN_SOURCE_GROUP) {
if (ssa->sin6.sin6_family != AF_INET6 ||
ssa->sin6.sin6_len != sizeof(struct sockaddr_in6))
return (EINVAL);
if (IN6_IS_ADDR_MULTICAST(&ssa->sin6.sin6_addr))
return (EINVAL);
/*
* TODO: Validate embedded scope ID in source
* list entry against passed-in ifp, if and only
* if source list filter entry is iface or node local.
*/
in6_clearscope(&ssa->sin6.sin6_addr);
ssa->sin6.sin6_port = 0;
ssa->sin6.sin6_scope_id = 0;
}
if (gsr.gsr_interface == 0 || V_if_index < gsr.gsr_interface)
return (EADDRNOTAVAIL);
ifp = ifnet_byindex(gsr.gsr_interface);
break;
default:
CTR2(KTR_MLD, "%s: unknown sopt_name %d",
__func__, sopt->sopt_name);
return (EOPNOTSUPP);
break;
}
if (!IN6_IS_ADDR_MULTICAST(&gsa->sin6.sin6_addr))
return (EINVAL);
if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0)
return (EADDRNOTAVAIL);
gsa->sin6.sin6_port = 0;
gsa->sin6.sin6_scope_id = 0;
/*
* Always set the scope zone ID on memberships created from userland.
* Use the passed-in ifp to do this.
* XXX The in6_setscope() return value is meaningless.
* XXX SCOPE6_LOCK() is taken by in6_setscope().
*/
(void)in6_setscope(&gsa->sin6.sin6_addr, ifp, NULL);
IN6_MULTI_LOCK();
/*
* Find the membership in the membership list.
*/
imo = in6p_findmoptions(inp);
imf = im6o_match_group(imo, ifp, &gsa->sa);
if (imf == NULL) {
is_new = 1;
inm = NULL;
if (ip6_mfilter_count(&imo->im6o_head) >= IPV6_MAX_MEMBERSHIPS) {
error = ENOMEM;
goto out_in6p_locked;
}
} else {
is_new = 0;
inm = imf->im6f_in6m;
if (ssa->ss.ss_family != AF_UNSPEC) {
/*
* MCAST_JOIN_SOURCE_GROUP on an exclusive membership
* is an error. On an existing inclusive membership,
* it just adds the source to the filter list.
*/
if (imf->im6f_st[1] != MCAST_INCLUDE) {
error = EINVAL;
goto out_in6p_locked;
}
/*
* Throw out duplicates.
*
* XXX FIXME: This makes a naive assumption that
* even if entries exist for *ssa in this imf,
* they will be rejected as dupes, even if they
* are not valid in the current mode (in-mode).
*
* in6_msource is transactioned just as for anything
* else in SSM -- but note naive use of in6m_graft()
* below for allocating new filter entries.
*
* This is only an issue if someone mixes the
* full-state SSM API with the delta-based API,
* which is discouraged in the relevant RFCs.
*/
lims = im6o_match_source(imf, &ssa->sa);
if (lims != NULL /*&&
lims->im6sl_st[1] == MCAST_INCLUDE*/) {
error = EADDRNOTAVAIL;
goto out_in6p_locked;
}
} else {
/*
* MCAST_JOIN_GROUP alone, on any existing membership,
* is rejected, to stop the same inpcb tying up
* multiple refs to the in_multi.
* On an existing inclusive membership, this is also
* an error; if you want to change filter mode,
* you must use the userland API setsourcefilter().
* XXX We don't reject this for imf in UNDEFINED
* state at t1, because allocation of a filter
* is atomic with allocation of a membership.
*/
error = EADDRINUSE;
goto out_in6p_locked;
}
}
/*
* Begin state merge transaction at socket layer.
*/
INP_WLOCK_ASSERT(inp);
/*
* Graft new source into filter list for this inpcb's
* membership of the group. The in6_multi may not have
* been allocated yet if this is a new membership, however,
* the in_mfilter slot will be allocated and must be initialized.
*
* Note: Grafting of exclusive mode filters doesn't happen
* in this path.
* XXX: Should check for non-NULL lims (node exists but may
* not be in-mode) for interop with full-state API.
*/
if (ssa->ss.ss_family != AF_UNSPEC) {
/* Membership starts in IN mode */
if (is_new) {
CTR1(KTR_MLD, "%s: new join w/source", __func__);
imf = ip6_mfilter_alloc(M_NOWAIT, MCAST_UNDEFINED, MCAST_INCLUDE);
if (imf == NULL) {
error = ENOMEM;
goto out_in6p_locked;
}
} else {
CTR2(KTR_MLD, "%s: %s source", __func__, "allow");
}
lims = im6f_graft(imf, MCAST_INCLUDE, &ssa->sin6);
if (lims == NULL) {
CTR1(KTR_MLD, "%s: merge imf state failed",
__func__);
error = ENOMEM;
goto out_in6p_locked;
}
} else {
/* No address specified; Membership starts in EX mode */
if (is_new) {
CTR1(KTR_MLD, "%s: new join w/o source", __func__);
imf = ip6_mfilter_alloc(M_NOWAIT, MCAST_UNDEFINED, MCAST_EXCLUDE);
if (imf == NULL) {
error = ENOMEM;
goto out_in6p_locked;
}
}
}
/*
* Begin state merge transaction at MLD layer.
*/
if (is_new) {
in_pcbref(inp);
INP_WUNLOCK(inp);
error = in6_joingroup_locked(ifp, &gsa->sin6.sin6_addr, imf,
&imf->im6f_in6m, 0);
INP_WLOCK(inp);
if (in_pcbrele_wlocked(inp)) {
error = ENXIO;
goto out_in6p_unlocked;
}
if (error) {
goto out_in6p_locked;
}
/*
* NOTE: Refcount from in6_joingroup_locked()
* is protecting membership.
*/
ip6_mfilter_insert(&imo->im6o_head, imf);
} else {
CTR1(KTR_MLD, "%s: merge inm state", __func__);
IN6_MULTI_LIST_LOCK();
error = in6m_merge(inm, imf);
if (error) {
CTR1(KTR_MLD, "%s: failed to merge inm state",
__func__);
IN6_MULTI_LIST_UNLOCK();
im6f_rollback(imf);
im6f_reap(imf);
goto out_in6p_locked;
}
CTR1(KTR_MLD, "%s: doing mld downcall", __func__);
error = mld_change_state(inm, 0);
IN6_MULTI_LIST_UNLOCK();
if (error) {
CTR1(KTR_MLD, "%s: failed mld downcall",
__func__);
im6f_rollback(imf);
im6f_reap(imf);
goto out_in6p_locked;
}
}
im6f_commit(imf);
imf = NULL;
out_in6p_locked:
INP_WUNLOCK(inp);
out_in6p_unlocked:
IN6_MULTI_UNLOCK();
if (is_new && imf) {
if (imf->im6f_in6m != NULL) {
struct in6_multi_head inmh;
SLIST_INIT(&inmh);
SLIST_INSERT_HEAD(&inmh, imf->im6f_in6m, in6m_defer);
in6m_release_list_deferred(&inmh);
}
ip6_mfilter_free(imf);
}
return (error);
}
/*
* Leave an IPv6 multicast group on an inpcb, possibly with a source.
*/
static int
in6p_leave_group(struct inpcb *inp, struct sockopt *sopt)
{
struct ipv6_mreq mreq;
struct group_source_req gsr;
sockunion_t *gsa, *ssa;
struct ifnet *ifp;
struct in6_mfilter *imf;
struct ip6_moptions *imo;
struct in6_msource *ims;
struct in6_multi *inm;
uint32_t ifindex;
int error;
bool is_final;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
ifp = NULL;
ifindex = 0;
error = 0;
is_final = true;
memset(&gsr, 0, sizeof(struct group_source_req));
gsa = (sockunion_t *)&gsr.gsr_group;
gsa->ss.ss_family = AF_UNSPEC;
ssa = (sockunion_t *)&gsr.gsr_source;
ssa->ss.ss_family = AF_UNSPEC;
/*
* Chew everything passed in up into a struct group_source_req
* as that is easier to process.
* Note: Any embedded scope ID in the multicast group passed
* in by userland is ignored, the interface index is the recommended
* mechanism to specify an interface; see below.
*/
switch (sopt->sopt_name) {
case IPV6_LEAVE_GROUP:
error = sooptcopyin(sopt, &mreq, sizeof(struct ipv6_mreq),
sizeof(struct ipv6_mreq));
if (error)
return (error);
gsa->sin6.sin6_family = AF_INET6;
gsa->sin6.sin6_len = sizeof(struct sockaddr_in6);
gsa->sin6.sin6_addr = mreq.ipv6mr_multiaddr;
gsa->sin6.sin6_port = 0;
gsa->sin6.sin6_scope_id = 0;
ifindex = mreq.ipv6mr_interface;
break;
case MCAST_LEAVE_GROUP:
case MCAST_LEAVE_SOURCE_GROUP:
if (sopt->sopt_name == MCAST_LEAVE_GROUP) {
error = sooptcopyin(sopt, &gsr,
sizeof(struct group_req),
sizeof(struct group_req));
} else if (sopt->sopt_name == MCAST_LEAVE_SOURCE_GROUP) {
error = sooptcopyin(sopt, &gsr,
sizeof(struct group_source_req),
sizeof(struct group_source_req));
}
if (error)
return (error);
if (gsa->sin6.sin6_family != AF_INET6 ||
gsa->sin6.sin6_len != sizeof(struct sockaddr_in6))
return (EINVAL);
if (sopt->sopt_name == MCAST_LEAVE_SOURCE_GROUP) {
if (ssa->sin6.sin6_family != AF_INET6 ||
ssa->sin6.sin6_len != sizeof(struct sockaddr_in6))
return (EINVAL);
if (IN6_IS_ADDR_MULTICAST(&ssa->sin6.sin6_addr))
return (EINVAL);
/*
* TODO: Validate embedded scope ID in source
* list entry against passed-in ifp, if and only
* if source list filter entry is iface or node local.
*/
in6_clearscope(&ssa->sin6.sin6_addr);
}
gsa->sin6.sin6_port = 0;
gsa->sin6.sin6_scope_id = 0;
ifindex = gsr.gsr_interface;
break;
default:
CTR2(KTR_MLD, "%s: unknown sopt_name %d",
__func__, sopt->sopt_name);
return (EOPNOTSUPP);
break;
}
if (!IN6_IS_ADDR_MULTICAST(&gsa->sin6.sin6_addr))
return (EINVAL);
/*
* Validate interface index if provided. If no interface index
* was provided separately, attempt to look the membership up
* from the default scope as a last resort to disambiguate
* the membership we are being asked to leave.
* XXX SCOPE6 lock potentially taken here.
*/
if (ifindex != 0) {
if (V_if_index < ifindex)
return (EADDRNOTAVAIL);
ifp = ifnet_byindex(ifindex);
if (ifp == NULL)
return (EADDRNOTAVAIL);
(void)in6_setscope(&gsa->sin6.sin6_addr, ifp, NULL);
} else {
error = sa6_embedscope(&gsa->sin6, V_ip6_use_defzone);
if (error)
return (EADDRNOTAVAIL);
/*
* Some badly behaved applications don't pass an ifindex
* or a scope ID, which is an API violation. In this case,
* perform a lookup as per a v6 join.
*
* XXX For now, stomp on zone ID for the corner case.
* This is not the 'KAME way', but we need to see the ifp
* directly until such time as this implementation is
* refactored, assuming the scope IDs are the way to go.
*/
ifindex = ntohs(gsa->sin6.sin6_addr.s6_addr16[1]);
if (ifindex == 0) {
CTR2(KTR_MLD, "%s: warning: no ifindex, looking up "
"ifp for group %s.", __func__,
ip6_sprintf(ip6tbuf, &gsa->sin6.sin6_addr));
ifp = in6p_lookup_mcast_ifp(inp, &gsa->sin6);
} else {
ifp = ifnet_byindex(ifindex);
}
if (ifp == NULL)
return (EADDRNOTAVAIL);
}
CTR2(KTR_MLD, "%s: ifp = %p", __func__, ifp);
KASSERT(ifp != NULL, ("%s: ifp did not resolve", __func__));
IN6_MULTI_LOCK();
/*
* Find the membership in the membership list.
*/
imo = in6p_findmoptions(inp);
imf = im6o_match_group(imo, ifp, &gsa->sa);
if (imf == NULL) {
error = EADDRNOTAVAIL;
goto out_in6p_locked;
}
inm = imf->im6f_in6m;
if (ssa->ss.ss_family != AF_UNSPEC)
is_final = false;
/*
* Begin state merge transaction at socket layer.
*/
INP_WLOCK_ASSERT(inp);
/*
* If we were instructed only to leave a given source, do so.
* MCAST_LEAVE_SOURCE_GROUP is only valid for inclusive memberships.
*/
if (is_final) {
ip6_mfilter_remove(&imo->im6o_head, imf);
im6f_leave(imf);
/*
* Give up the multicast address record to which
* the membership points.
*/
(void)in6_leavegroup_locked(inm, imf);
} else {
if (imf->im6f_st[0] == MCAST_EXCLUDE) {
error = EADDRNOTAVAIL;
goto out_in6p_locked;
}
ims = im6o_match_source(imf, &ssa->sa);
if (ims == NULL) {
CTR3(KTR_MLD, "%s: source %p %spresent", __func__,
ip6_sprintf(ip6tbuf, &ssa->sin6.sin6_addr),
"not ");
error = EADDRNOTAVAIL;
goto out_in6p_locked;
}
CTR2(KTR_MLD, "%s: %s source", __func__, "block");
error = im6f_prune(imf, &ssa->sin6);
if (error) {
CTR1(KTR_MLD, "%s: merge imf state failed",
__func__);
goto out_in6p_locked;
}
}
/*
* Begin state merge transaction at MLD layer.
*/
if (!is_final) {
CTR1(KTR_MLD, "%s: merge inm state", __func__);
IN6_MULTI_LIST_LOCK();
error = in6m_merge(inm, imf);
if (error) {
CTR1(KTR_MLD, "%s: failed to merge inm state",
__func__);
IN6_MULTI_LIST_UNLOCK();
im6f_rollback(imf);
im6f_reap(imf);
goto out_in6p_locked;
}
CTR1(KTR_MLD, "%s: doing mld downcall", __func__);
error = mld_change_state(inm, 0);
IN6_MULTI_LIST_UNLOCK();
if (error) {
CTR1(KTR_MLD, "%s: failed mld downcall",
__func__);
im6f_rollback(imf);
im6f_reap(imf);
goto out_in6p_locked;
}
}
im6f_commit(imf);
im6f_reap(imf);
out_in6p_locked:
INP_WUNLOCK(inp);
if (is_final && imf)
ip6_mfilter_free(imf);
IN6_MULTI_UNLOCK();
return (error);
}
/*
* Select the interface for transmitting IPv6 multicast datagrams.
*
* Either an instance of struct in6_addr or an instance of struct ipv6_mreqn
* may be passed to this socket option. An address of in6addr_any or an
* interface index of 0 is used to remove a previous selection.
* When no interface is selected, one is chosen for every send.
*/
static int
in6p_set_multicast_if(struct inpcb *inp, struct sockopt *sopt)
{
struct ifnet *ifp;
struct ip6_moptions *imo;
u_int ifindex;
int error;
if (sopt->sopt_valsize != sizeof(u_int))
return (EINVAL);
error = sooptcopyin(sopt, &ifindex, sizeof(u_int), sizeof(u_int));
if (error)
return (error);
if (V_if_index < ifindex)
return (EINVAL);
if (ifindex == 0)
ifp = NULL;
else {
ifp = ifnet_byindex(ifindex);
if (ifp == NULL)
return (EINVAL);
if ((ifp->if_flags & IFF_MULTICAST) == 0)
return (EADDRNOTAVAIL);
}
imo = in6p_findmoptions(inp);
imo->im6o_multicast_ifp = ifp;
INP_WUNLOCK(inp);
return (0);
}
/*
* Atomically set source filters on a socket for an IPv6 multicast group.
*
* SMPng: NOTE: Potentially calls malloc(M_WAITOK) with Giant held.
*/
static int
in6p_set_source_filters(struct inpcb *inp, struct sockopt *sopt)
{
struct __msfilterreq msfr;
sockunion_t *gsa;
struct ifnet *ifp;
struct in6_mfilter *imf;
struct ip6_moptions *imo;
struct in6_multi *inm;
int error;
error = sooptcopyin(sopt, &msfr, sizeof(struct __msfilterreq),
sizeof(struct __msfilterreq));
if (error)
return (error);
if (msfr.msfr_nsrcs > in6_mcast_maxsocksrc)
return (ENOBUFS);
if (msfr.msfr_fmode != MCAST_EXCLUDE &&
msfr.msfr_fmode != MCAST_INCLUDE)
return (EINVAL);
if (msfr.msfr_group.ss_family != AF_INET6 ||
msfr.msfr_group.ss_len != sizeof(struct sockaddr_in6))
return (EINVAL);
gsa = (sockunion_t *)&msfr.msfr_group;
if (!IN6_IS_ADDR_MULTICAST(&gsa->sin6.sin6_addr))
return (EINVAL);
gsa->sin6.sin6_port = 0; /* ignore port */
if (msfr.msfr_ifindex == 0 || V_if_index < msfr.msfr_ifindex)
return (EADDRNOTAVAIL);
ifp = ifnet_byindex(msfr.msfr_ifindex);
if (ifp == NULL)
return (EADDRNOTAVAIL);
(void)in6_setscope(&gsa->sin6.sin6_addr, ifp, NULL);
/*
* Take the INP write lock.
* Check if this socket is a member of this group.
*/
imo = in6p_findmoptions(inp);
imf = im6o_match_group(imo, ifp, &gsa->sa);
if (imf == NULL) {
error = EADDRNOTAVAIL;
goto out_in6p_locked;
}
inm = imf->im6f_in6m;
/*
* Begin state merge transaction at socket layer.
*/
INP_WLOCK_ASSERT(inp);
imf->im6f_st[1] = msfr.msfr_fmode;
/*
* Apply any new source filters, if present.
* Make a copy of the user-space source vector so
* that we may copy them with a single copyin. This
* allows us to deal with page faults up-front.
*/
if (msfr.msfr_nsrcs > 0) {
struct in6_msource *lims;
struct sockaddr_in6 *psin;
struct sockaddr_storage *kss, *pkss;
int i;
INP_WUNLOCK(inp);
CTR2(KTR_MLD, "%s: loading %lu source list entries",
__func__, (unsigned long)msfr.msfr_nsrcs);
kss = malloc(sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs,
M_TEMP, M_WAITOK);
error = copyin(msfr.msfr_srcs, kss,
sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs);
if (error) {
free(kss, M_TEMP);
return (error);
}
INP_WLOCK(inp);
/*
* Mark all source filters as UNDEFINED at t1.
* Restore new group filter mode, as im6f_leave()
* will set it to INCLUDE.
*/
im6f_leave(imf);
imf->im6f_st[1] = msfr.msfr_fmode;
/*
* Update socket layer filters at t1, lazy-allocating
* new entries. This saves a bunch of memory at the
* cost of one RB_FIND() per source entry; duplicate
* entries in the msfr_nsrcs vector are ignored.
* If we encounter an error, rollback transaction.
*
* XXX This too could be replaced with a set-symmetric
* difference like loop to avoid walking from root
* every time, as the key space is common.
*/
for (i = 0, pkss = kss; i < msfr.msfr_nsrcs; i++, pkss++) {
psin = (struct sockaddr_in6 *)pkss;
if (psin->sin6_family != AF_INET6) {
error = EAFNOSUPPORT;
break;
}
if (psin->sin6_len != sizeof(struct sockaddr_in6)) {
error = EINVAL;
break;
}
if (IN6_IS_ADDR_MULTICAST(&psin->sin6_addr)) {
error = EINVAL;
break;
}
/*
* TODO: Validate embedded scope ID in source
* list entry against passed-in ifp, if and only
* if source list filter entry is iface or node local.
*/
in6_clearscope(&psin->sin6_addr);
error = im6f_get_source(imf, psin, &lims);
if (error)
break;
lims->im6sl_st[1] = imf->im6f_st[1];
}
free(kss, M_TEMP);
}
if (error)
goto out_im6f_rollback;
INP_WLOCK_ASSERT(inp);
IN6_MULTI_LIST_LOCK();
/*
* Begin state merge transaction at MLD layer.
*/
CTR1(KTR_MLD, "%s: merge inm state", __func__);
error = in6m_merge(inm, imf);
if (error)
CTR1(KTR_MLD, "%s: failed to merge inm state", __func__);
else {
CTR1(KTR_MLD, "%s: doing mld downcall", __func__);
error = mld_change_state(inm, 0);
if (error)
CTR1(KTR_MLD, "%s: failed mld downcall", __func__);
}
IN6_MULTI_LIST_UNLOCK();
out_im6f_rollback:
if (error)
im6f_rollback(imf);
else
im6f_commit(imf);
im6f_reap(imf);
out_in6p_locked:
INP_WUNLOCK(inp);
return (error);
}
/*
* Set the IP multicast options in response to user setsockopt().
*
* Many of the socket options handled in this function duplicate the
* functionality of socket options in the regular unicast API. However,
* it is not possible to merge the duplicate code, because the idempotence
* of the IPv6 multicast part of the BSD Sockets API must be preserved;
* the effects of these options must be treated as separate and distinct.
*
* SMPng: XXX: Unlocked read of inp_socket believed OK.
*/
int
ip6_setmoptions(struct inpcb *inp, struct sockopt *sopt)
{
struct ip6_moptions *im6o;
int error;
error = 0;
/*
* If socket is neither of type SOCK_RAW or SOCK_DGRAM,
* or is a divert socket, reject it.
*/
if (inp->inp_socket->so_proto->pr_protocol == IPPROTO_DIVERT ||
(inp->inp_socket->so_proto->pr_type != SOCK_RAW &&
inp->inp_socket->so_proto->pr_type != SOCK_DGRAM))
return (EOPNOTSUPP);
switch (sopt->sopt_name) {
case IPV6_MULTICAST_IF:
error = in6p_set_multicast_if(inp, sopt);
break;
case IPV6_MULTICAST_HOPS: {
int hlim;
if (sopt->sopt_valsize != sizeof(int)) {
error = EINVAL;
break;
}
error = sooptcopyin(sopt, &hlim, sizeof(hlim), sizeof(int));
if (error)
break;
if (hlim < -1 || hlim > 255) {
error = EINVAL;
break;
} else if (hlim == -1) {
hlim = V_ip6_defmcasthlim;
}
im6o = in6p_findmoptions(inp);
im6o->im6o_multicast_hlim = hlim;
INP_WUNLOCK(inp);
break;
}
case IPV6_MULTICAST_LOOP: {
u_int loop;
/*
* Set the loopback flag for outgoing multicast packets.
* Must be zero or one.
*/
if (sopt->sopt_valsize != sizeof(u_int)) {
error = EINVAL;
break;
}
error = sooptcopyin(sopt, &loop, sizeof(u_int), sizeof(u_int));
if (error)
break;
if (loop > 1) {
error = EINVAL;
break;
}
im6o = in6p_findmoptions(inp);
im6o->im6o_multicast_loop = loop;
INP_WUNLOCK(inp);
break;
}
case IPV6_JOIN_GROUP:
case MCAST_JOIN_GROUP:
case MCAST_JOIN_SOURCE_GROUP:
error = in6p_join_group(inp, sopt);
break;
case IPV6_LEAVE_GROUP:
case MCAST_LEAVE_GROUP:
case MCAST_LEAVE_SOURCE_GROUP:
error = in6p_leave_group(inp, sopt);
break;
case MCAST_BLOCK_SOURCE:
case MCAST_UNBLOCK_SOURCE:
error = in6p_block_unblock_source(inp, sopt);
break;
case IPV6_MSFILTER:
error = in6p_set_source_filters(inp, sopt);
break;
default:
error = EOPNOTSUPP;
break;
}
INP_UNLOCK_ASSERT(inp);
return (error);
}
/*
* Expose MLD's multicast filter mode and source list(s) to userland,
* keyed by (ifindex, group).
* The filter mode is written out as a uint32_t, followed by
* 0..n of struct in6_addr.
* For use by ifmcstat(8).
* SMPng: NOTE: unlocked read of ifindex space.
*/
static int
sysctl_ip6_mcast_filters(SYSCTL_HANDLER_ARGS)
{
struct in6_addr mcaddr;
struct in6_addr src;
struct epoch_tracker et;
struct ifnet *ifp;
struct ifmultiaddr *ifma;
struct in6_multi *inm;
struct ip6_msource *ims;
int *name;
int retval;
u_int namelen;
uint32_t fmode, ifindex;
#ifdef KTR
char ip6tbuf[INET6_ADDRSTRLEN];
#endif
name = (int *)arg1;
namelen = arg2;
if (req->newptr != NULL)
return (EPERM);
/* int: ifindex + 4 * 32 bits of IPv6 address */
if (namelen != 5)
return (EINVAL);
ifindex = name[0];
if (ifindex <= 0 || ifindex > V_if_index) {
CTR2(KTR_MLD, "%s: ifindex %u out of range",
__func__, ifindex);
return (ENOENT);
}
memcpy(&mcaddr, &name[1], sizeof(struct in6_addr));
if (!IN6_IS_ADDR_MULTICAST(&mcaddr)) {
CTR2(KTR_MLD, "%s: group %s is not multicast",
__func__, ip6_sprintf(ip6tbuf, &mcaddr));
return (EINVAL);
}
NET_EPOCH_ENTER(et);
ifp = ifnet_byindex(ifindex);
if (ifp == NULL) {
NET_EPOCH_EXIT(et);
CTR2(KTR_MLD, "%s: no ifp for ifindex %u",
__func__, ifindex);
return (ENOENT);
}
/*
* Internal MLD lookups require that scope/zone ID is set.
*/
(void)in6_setscope(&mcaddr, ifp, NULL);
retval = sysctl_wire_old_buffer(req,
sizeof(uint32_t) + (in6_mcast_maxgrpsrc * sizeof(struct in6_addr)));
if (retval) {
NET_EPOCH_EXIT(et);
return (retval);
}
IN6_MULTI_LOCK();
IN6_MULTI_LIST_LOCK();
CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
inm = in6m_ifmultiaddr_get_inm(ifma);
if (inm == NULL)
continue;
if (!IN6_ARE_ADDR_EQUAL(&inm->in6m_addr, &mcaddr))
continue;
fmode = inm->in6m_st[1].iss_fmode;
retval = SYSCTL_OUT(req, &fmode, sizeof(uint32_t));
if (retval != 0)
break;
RB_FOREACH(ims, ip6_msource_tree, &inm->in6m_srcs) {
CTR2(KTR_MLD, "%s: visit node %p", __func__, ims);
/*
* Only copy-out sources which are in-mode.
*/
if (fmode != im6s_get_mode(inm, ims, 1)) {
CTR1(KTR_MLD, "%s: skip non-in-mode",
__func__);
continue;
}
src = ims->im6s_addr;
retval = SYSCTL_OUT(req, &src,
sizeof(struct in6_addr));
if (retval != 0)
break;
}
}
IN6_MULTI_LIST_UNLOCK();
IN6_MULTI_UNLOCK();
NET_EPOCH_EXIT(et);
return (retval);
}
#ifdef KTR
static const char *in6m_modestrs[] = { "un", "in", "ex" };
static const char *
in6m_mode_str(const int mode)
{
if (mode >= MCAST_UNDEFINED && mode <= MCAST_EXCLUDE)
return (in6m_modestrs[mode]);
return ("??");
}
static const char *in6m_statestrs[] = {
"not-member",
"silent",
"idle",
"lazy",
"sleeping",
"awakening",
"query-pending",
"sg-query-pending",
"leaving"
};
static const char *
in6m_state_str(const int state)
{
if (state >= MLD_NOT_MEMBER && state <= MLD_LEAVING_MEMBER)
return (in6m_statestrs[state]);
return ("??");
}
/*
* Dump an in6_multi structure to the console.
*/
void
in6m_print(const struct in6_multi *inm)
{
int t;
char ip6tbuf[INET6_ADDRSTRLEN];
if ((ktr_mask & KTR_MLD) == 0)
return;
printf("%s: --- begin in6m %p ---\n", __func__, inm);
printf("addr %s ifp %p(%s) ifma %p\n",
ip6_sprintf(ip6tbuf, &inm->in6m_addr),
inm->in6m_ifp,
if_name(inm->in6m_ifp),
inm->in6m_ifma);
printf("timer %u state %s refcount %u scq.len %u\n",
inm->in6m_timer,
in6m_state_str(inm->in6m_state),
inm->in6m_refcount,
mbufq_len(&inm->in6m_scq));
printf("mli %p nsrc %lu sctimer %u scrv %u\n",
inm->in6m_mli,
inm->in6m_nsrc,
inm->in6m_sctimer,
inm->in6m_scrv);
for (t = 0; t < 2; t++) {
printf("t%d: fmode %s asm %u ex %u in %u rec %u\n", t,
in6m_mode_str(inm->in6m_st[t].iss_fmode),
inm->in6m_st[t].iss_asm,
inm->in6m_st[t].iss_ex,
inm->in6m_st[t].iss_in,
inm->in6m_st[t].iss_rec);
}
printf("%s: --- end in6m %p ---\n", __func__, inm);
}
#else /* !KTR */
void
in6m_print(const struct in6_multi *inm)
{
}
#endif /* KTR */
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