freebsd-skq/sys/netinet6/in6_mcast.c
2020-09-01 21:19:14 +00:00

2904 lines
75 KiB
C

/*-
* 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 = EINVAL;
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 */