/*
   *	Multicast support for IPv6

   *	Linux INET6 implementation

   *
   *	Authors:

   *	Pedro Roque		<roque@di.fc.ul.pt>

   *

   *	Based on linux/ipv4/igmp.c and linux/ipv4/ip_sockglue.c

   *
   *	This program is free software; you can redistribute it and/or
   *      modify it under the terms of the GNU General Public License
   *      as published by the Free Software Foundation; either version
   *      2 of the License, or (at your option) any later version.
   */
  
  /* Changes:
   *
   *	yoshfuji	: fix format of router-alert option
   *	YOSHIFUJI Hideaki @USAGI:
   *		Fixed source address for MLD message based on
   *		<draft-ietf-magma-mld-source-05.txt>.
   *	YOSHIFUJI Hideaki @USAGI:
   *		- Ignore Queries for invalid addresses.
   *		- MLD for link-local addresses.
   *	David L Stevens <dlstevens@us.ibm.com>:
   *		- MLDv2 support
   */

  #include <linux/module.h>
  #include <linux/errno.h>
  #include <linux/types.h>
  #include <linux/string.h>
  #include <linux/socket.h>
  #include <linux/sockios.h>
  #include <linux/jiffies.h>
  #include <linux/times.h>
  #include <linux/net.h>
  #include <linux/in.h>
  #include <linux/in6.h>
  #include <linux/netdevice.h>
  #include <linux/if_arp.h>
  #include <linux/route.h>
  #include <linux/init.h>
  #include <linux/proc_fs.h>
  #include <linux/seq_file.h>

  #include <linux/slab.h>

  #include <net/mld.h>

  
  #include <linux/netfilter.h>
  #include <linux/netfilter_ipv6.h>

  #include <net/net_namespace.h>

  #include <net/sock.h>
  #include <net/snmp.h>
  
  #include <net/ipv6.h>
  #include <net/protocol.h>
  #include <net/if_inet6.h>
  #include <net/ndisc.h>
  #include <net/addrconf.h>
  #include <net/ip6_route.h>

  #include <net/inet_common.h>

  
  #include <net/ip6_checksum.h>
  
  /* Set to 3 to get tracing... */
  #define MCAST_DEBUG 2
  
  #if MCAST_DEBUG >= 3
  #define MDBG(x) printk x
  #else
  #define MDBG(x)
  #endif

  /* Ensure that we have struct in6_addr aligned on 32bit word. */
  static void *__mld2_query_bugs[] __attribute__((__unused__)) = {
  	BUILD_BUG_ON_NULL(offsetof(struct mld2_query, mld2q_srcs) % 4),
  	BUILD_BUG_ON_NULL(offsetof(struct mld2_report, mld2r_grec) % 4),
  	BUILD_BUG_ON_NULL(offsetof(struct mld2_grec, grec_mca) % 4)

  };
  
  static struct in6_addr mld2_all_mcr = MLD2_ALL_MCR_INIT;
  
  /* Big mc list lock for all the sockets */

  static DEFINE_SPINLOCK(ipv6_sk_mc_lock);

  static void igmp6_join_group(struct ifmcaddr6 *ma);
  static void igmp6_leave_group(struct ifmcaddr6 *ma);
  static void igmp6_timer_handler(unsigned long data);
  
  static void mld_gq_timer_expire(unsigned long data);
  static void mld_ifc_timer_expire(unsigned long data);
  static void mld_ifc_event(struct inet6_dev *idev);
  static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *pmc);

  static void mld_del_delrec(struct inet6_dev *idev, const struct in6_addr *addr);

  static void mld_clear_delrec(struct inet6_dev *idev);
  static int sf_setstate(struct ifmcaddr6 *pmc);
  static void sf_markstate(struct ifmcaddr6 *pmc);
  static void ip6_mc_clear_src(struct ifmcaddr6 *pmc);

  static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
  			  int sfmode, int sfcount, const struct in6_addr *psfsrc,

  			  int delta);

  static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
  			  int sfmode, int sfcount, const struct in6_addr *psfsrc,

  			  int delta);
  static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
  			    struct inet6_dev *idev);
  
  
  #define IGMP6_UNSOLICITED_IVAL	(10*HZ)
  #define MLD_QRV_DEFAULT		2

  #define MLD_V1_SEEN(idev) (dev_net((idev)->dev)->ipv6.devconf_all->force_mld_version == 1 || \

  		(idev)->cnf.force_mld_version == 1 || \
  		((idev)->mc_v1_seen && \
  		time_before(jiffies, (idev)->mc_v1_seen)))

  #define IPV6_MLD_MAX_MSF	64

  int sysctl_mld_max_msf __read_mostly = IPV6_MLD_MAX_MSF;

  
  /*
   *	socket join on multicast group
   */

  #define for_each_pmc_rcu(np, pmc)				\
  	for (pmc = rcu_dereference(np->ipv6_mc_list);		\
  	     pmc != NULL;					\
  	     pmc = rcu_dereference(pmc->next))

  int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)

  {
  	struct net_device *dev = NULL;
  	struct ipv6_mc_socklist *mc_lst;
  	struct ipv6_pinfo *np = inet6_sk(sk);

  	struct net *net = sock_net(sk);

  	int err;
  
  	if (!ipv6_addr_is_multicast(addr))
  		return -EINVAL;

  	rcu_read_lock();
  	for_each_pmc_rcu(np, mc_lst) {

  		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
  		    ipv6_addr_equal(&mc_lst->addr, addr)) {

  			rcu_read_unlock();

  			return -EADDRINUSE;
  		}
  	}

  	rcu_read_unlock();

  	mc_lst = sock_kmalloc(sk, sizeof(struct ipv6_mc_socklist), GFP_KERNEL);
  
  	if (mc_lst == NULL)
  		return -ENOMEM;
  
  	mc_lst->next = NULL;

  	mc_lst->addr = *addr;

  	rcu_read_lock();

  	if (ifindex == 0) {
  		struct rt6_info *rt;

  		rt = rt6_lookup(net, addr, NULL, 0, 0);

  		if (rt) {

  			dev = rt->dst.dev;

  			dst_release(&rt->dst);

  		}
  	} else

  		dev = dev_get_by_index_rcu(net, ifindex);

  
  	if (dev == NULL) {

  		rcu_read_unlock();

  		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
  		return -ENODEV;
  	}
  
  	mc_lst->ifindex = dev->ifindex;
  	mc_lst->sfmode = MCAST_EXCLUDE;

  	rwlock_init(&mc_lst->sflock);

  	mc_lst->sflist = NULL;
  
  	/*
  	 *	now add/increase the group membership on the device
  	 */
  
  	err = ipv6_dev_mc_inc(dev, addr);
  
  	if (err) {

  		rcu_read_unlock();

  		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));

  		return err;
  	}

  	spin_lock(&ipv6_sk_mc_lock);

  	mc_lst->next = np->ipv6_mc_list;

  	rcu_assign_pointer(np->ipv6_mc_list, mc_lst);
  	spin_unlock(&ipv6_sk_mc_lock);

  	rcu_read_unlock();

  
  	return 0;
  }
  
  /*
   *	socket leave on multicast group
   */

  int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)

  {
  	struct ipv6_pinfo *np = inet6_sk(sk);

  	struct ipv6_mc_socklist *mc_lst;
  	struct ipv6_mc_socklist __rcu **lnk;

  	struct net *net = sock_net(sk);

  	spin_lock(&ipv6_sk_mc_lock);
  	for (lnk = &np->ipv6_mc_list;
  	     (mc_lst = rcu_dereference_protected(*lnk,
  			lockdep_is_held(&ipv6_sk_mc_lock))) !=NULL ;
  	      lnk = &mc_lst->next) {

  		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
  		    ipv6_addr_equal(&mc_lst->addr, addr)) {
  			struct net_device *dev;
  
  			*lnk = mc_lst->next;

  			spin_unlock(&ipv6_sk_mc_lock);

  			rcu_read_lock();
  			dev = dev_get_by_index_rcu(net, mc_lst->ifindex);

  			if (dev != NULL) {

  				struct inet6_dev *idev = __in6_dev_get(dev);

  				(void) ip6_mc_leave_src(sk, mc_lst, idev);

  				if (idev)

  					__ipv6_dev_mc_dec(idev, &mc_lst->addr);

  			} else
  				(void) ip6_mc_leave_src(sk, mc_lst, NULL);

  			rcu_read_unlock();

  			atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);

  			kfree_rcu(mc_lst, rcu);

  			return 0;
  		}
  	}

  	spin_unlock(&ipv6_sk_mc_lock);

  	return -EADDRNOTAVAIL;

  }

  /* called with rcu_read_lock() */
  static struct inet6_dev *ip6_mc_find_dev_rcu(struct net *net,

  					     const struct in6_addr *group,

  					     int ifindex)

  {
  	struct net_device *dev = NULL;
  	struct inet6_dev *idev = NULL;
  
  	if (ifindex == 0) {

  		struct rt6_info *rt = rt6_lookup(net, group, NULL, 0, 0);

  		if (rt) {

  			dev = rt->dst.dev;

  			dev_hold(dev);

  			dst_release(&rt->dst);

  		}
  	} else

  		dev = dev_get_by_index_rcu(net, ifindex);

  
  	if (!dev)

  		return NULL;
  	idev = __in6_dev_get(dev);

  	if (!idev)

  		return NULL;

  	read_lock_bh(&idev->lock);

  	if (idev->dead) {
  		read_unlock_bh(&idev->lock);
  		return NULL;
  	}

  	return idev;
  }
  
  void ipv6_sock_mc_close(struct sock *sk)
  {
  	struct ipv6_pinfo *np = inet6_sk(sk);
  	struct ipv6_mc_socklist *mc_lst;

  	struct net *net = sock_net(sk);

  	spin_lock(&ipv6_sk_mc_lock);
  	while ((mc_lst = rcu_dereference_protected(np->ipv6_mc_list,
  				lockdep_is_held(&ipv6_sk_mc_lock))) != NULL) {

  		struct net_device *dev;
  
  		np->ipv6_mc_list = mc_lst->next;

  		spin_unlock(&ipv6_sk_mc_lock);

  		rcu_read_lock();
  		dev = dev_get_by_index_rcu(net, mc_lst->ifindex);

  		if (dev) {

  			struct inet6_dev *idev = __in6_dev_get(dev);

  			(void) ip6_mc_leave_src(sk, mc_lst, idev);

  			if (idev)

  				__ipv6_dev_mc_dec(idev, &mc_lst->addr);

  		} else
  			(void) ip6_mc_leave_src(sk, mc_lst, NULL);

  		rcu_read_unlock();

  		atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);

  		kfree_rcu(mc_lst, rcu);

  
  		spin_lock(&ipv6_sk_mc_lock);

  	}

  	spin_unlock(&ipv6_sk_mc_lock);

  }
  
  int ip6_mc_source(int add, int omode, struct sock *sk,
  	struct group_source_req *pgsr)
  {
  	struct in6_addr *source, *group;
  	struct ipv6_mc_socklist *pmc;

  	struct inet6_dev *idev;
  	struct ipv6_pinfo *inet6 = inet6_sk(sk);
  	struct ip6_sf_socklist *psl;

  	struct net *net = sock_net(sk);

  	int i, j, rv;

  	int leavegroup = 0;

  	int pmclocked = 0;

  	int err;

  	source = &((struct sockaddr_in6 *)&pgsr->gsr_source)->sin6_addr;
  	group = &((struct sockaddr_in6 *)&pgsr->gsr_group)->sin6_addr;
  
  	if (!ipv6_addr_is_multicast(group))
  		return -EINVAL;

  	rcu_read_lock();
  	idev = ip6_mc_find_dev_rcu(net, group, pgsr->gsr_interface);
  	if (!idev) {
  		rcu_read_unlock();

  		return -ENODEV;

  	}

  
  	err = -EADDRNOTAVAIL;

  	for_each_pmc_rcu(inet6, pmc) {

  		if (pgsr->gsr_interface && pmc->ifindex != pgsr->gsr_interface)
  			continue;
  		if (ipv6_addr_equal(&pmc->addr, group))
  			break;
  	}

  	if (!pmc) {		/* must have a prior join */
  		err = -EINVAL;

  		goto done;

  	}

  	/* if a source filter was set, must be the same mode as before */
  	if (pmc->sflist) {

  		if (pmc->sfmode != omode) {
  			err = -EINVAL;

  			goto done;

  		}

  	} else if (pmc->sfmode != omode) {
  		/* allow mode switches for empty-set filters */
  		ip6_mc_add_src(idev, group, omode, 0, NULL, 0);
  		ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
  		pmc->sfmode = omode;
  	}

  	write_lock(&pmc->sflock);

  	pmclocked = 1;

  	psl = pmc->sflist;
  	if (!add) {
  		if (!psl)

  			goto done;	/* err = -EADDRNOTAVAIL */

  		rv = !0;
  		for (i=0; i<psl->sl_count; i++) {
  			rv = memcmp(&psl->sl_addr[i], source,
  				sizeof(struct in6_addr));
  			if (rv == 0)
  				break;
  		}
  		if (rv)		/* source not found */

  			goto done;	/* err = -EADDRNOTAVAIL */

  		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
  		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
  			leavegroup = 1;
  			goto done;
  		}

  		/* update the interface filter */
  		ip6_mc_del_src(idev, group, omode, 1, source, 1);
  
  		for (j=i+1; j<psl->sl_count; j++)
  			psl->sl_addr[j-1] = psl->sl_addr[j];
  		psl->sl_count--;
  		err = 0;
  		goto done;
  	}
  	/* else, add a new source to the filter */
  
  	if (psl && psl->sl_count >= sysctl_mld_max_msf) {
  		err = -ENOBUFS;
  		goto done;
  	}
  	if (!psl || psl->sl_count == psl->sl_max) {
  		struct ip6_sf_socklist *newpsl;
  		int count = IP6_SFBLOCK;
  
  		if (psl)
  			count += psl->sl_max;

  		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(count), GFP_ATOMIC);

  		if (!newpsl) {
  			err = -ENOBUFS;
  			goto done;
  		}
  		newpsl->sl_max = count;
  		newpsl->sl_count = count - IP6_SFBLOCK;
  		if (psl) {
  			for (i=0; i<psl->sl_count; i++)
  				newpsl->sl_addr[i] = psl->sl_addr[i];
  			sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
  		}
  		pmc->sflist = psl = newpsl;
  	}
  	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
  	for (i=0; i<psl->sl_count; i++) {
  		rv = memcmp(&psl->sl_addr[i], source, sizeof(struct in6_addr));
  		if (rv == 0)
  			break;
  	}
  	if (rv == 0)		/* address already there is an error */
  		goto done;
  	for (j=psl->sl_count-1; j>=i; j--)
  		psl->sl_addr[j+1] = psl->sl_addr[j];
  	psl->sl_addr[i] = *source;
  	psl->sl_count++;
  	err = 0;
  	/* update the interface list */
  	ip6_mc_add_src(idev, group, omode, 1, source, 1);
  done:

  	if (pmclocked)

  		write_unlock(&pmc->sflock);

  	read_unlock_bh(&idev->lock);

  	rcu_read_unlock();

  	if (leavegroup)
  		return ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);

  	return err;
  }
  
  int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf)
  {

  	const struct in6_addr *group;

  	struct ipv6_mc_socklist *pmc;

  	struct inet6_dev *idev;
  	struct ipv6_pinfo *inet6 = inet6_sk(sk);
  	struct ip6_sf_socklist *newpsl, *psl;

  	struct net *net = sock_net(sk);

  	int leavegroup = 0;

  	int i, err;
  
  	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
  
  	if (!ipv6_addr_is_multicast(group))
  		return -EINVAL;
  	if (gsf->gf_fmode != MCAST_INCLUDE &&
  	    gsf->gf_fmode != MCAST_EXCLUDE)
  		return -EINVAL;

  	rcu_read_lock();
  	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);

  	if (!idev) {
  		rcu_read_unlock();

  		return -ENODEV;

  	}

  	err = 0;

  	if (gsf->gf_fmode == MCAST_INCLUDE && gsf->gf_numsrc == 0) {
  		leavegroup = 1;
  		goto done;
  	}

  	for_each_pmc_rcu(inet6, pmc) {

  		if (pmc->ifindex != gsf->gf_interface)
  			continue;
  		if (ipv6_addr_equal(&pmc->addr, group))
  			break;
  	}

  	if (!pmc) {		/* must have a prior join */
  		err = -EINVAL;

  		goto done;

  	}

  	if (gsf->gf_numsrc) {

  		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(gsf->gf_numsrc),
  							  GFP_ATOMIC);

  		if (!newpsl) {
  			err = -ENOBUFS;
  			goto done;
  		}
  		newpsl->sl_max = newpsl->sl_count = gsf->gf_numsrc;
  		for (i=0; i<newpsl->sl_count; ++i) {
  			struct sockaddr_in6 *psin6;
  
  			psin6 = (struct sockaddr_in6 *)&gsf->gf_slist[i];
  			newpsl->sl_addr[i] = psin6->sin6_addr;
  		}
  		err = ip6_mc_add_src(idev, group, gsf->gf_fmode,
  			newpsl->sl_count, newpsl->sl_addr, 0);
  		if (err) {
  			sock_kfree_s(sk, newpsl, IP6_SFLSIZE(newpsl->sl_max));
  			goto done;
  		}

  	} else {

  		newpsl = NULL;

  		(void) ip6_mc_add_src(idev, group, gsf->gf_fmode, 0, NULL, 0);
  	}

  	write_lock(&pmc->sflock);

  	psl = pmc->sflist;
  	if (psl) {
  		(void) ip6_mc_del_src(idev, group, pmc->sfmode,
  			psl->sl_count, psl->sl_addr, 0);
  		sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
  	} else
  		(void) ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
  	pmc->sflist = newpsl;
  	pmc->sfmode = gsf->gf_fmode;

  	write_unlock(&pmc->sflock);

  	err = 0;

  done:
  	read_unlock_bh(&idev->lock);

  	rcu_read_unlock();

  	if (leavegroup)
  		err = ipv6_sock_mc_drop(sk, gsf->gf_interface, group);

  	return err;
  }
  
  int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
  	struct group_filter __user *optval, int __user *optlen)
  {
  	int err, i, count, copycount;

  	const struct in6_addr *group;

  	struct ipv6_mc_socklist *pmc;
  	struct inet6_dev *idev;

  	struct ipv6_pinfo *inet6 = inet6_sk(sk);
  	struct ip6_sf_socklist *psl;

  	struct net *net = sock_net(sk);

  
  	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
  
  	if (!ipv6_addr_is_multicast(group))
  		return -EINVAL;

  	rcu_read_lock();
  	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);

  	if (!idev) {
  		rcu_read_unlock();

  		return -ENODEV;

  	}

  
  	err = -EADDRNOTAVAIL;

  	/*
  	 * changes to the ipv6_mc_list require the socket lock and
  	 * a read lock on ip6_sk_mc_lock. We have the socket lock,
  	 * so reading the list is safe.
  	 */

  	for_each_pmc_rcu(inet6, pmc) {

  		if (pmc->ifindex != gsf->gf_interface)
  			continue;
  		if (ipv6_addr_equal(group, &pmc->addr))
  			break;
  	}
  	if (!pmc)		/* must have a prior join */
  		goto done;
  	gsf->gf_fmode = pmc->sfmode;
  	psl = pmc->sflist;
  	count = psl ? psl->sl_count : 0;
  	read_unlock_bh(&idev->lock);

  	rcu_read_unlock();

  
  	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
  	gsf->gf_numsrc = count;
  	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
  	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
  		return -EFAULT;
  	}

  	/* changes to psl require the socket lock, a read lock on
  	 * on ipv6_sk_mc_lock and a write lock on pmc->sflock. We
  	 * have the socket lock, so reading here is safe.
  	 */

  	for (i=0; i<copycount; i++) {
  		struct sockaddr_in6 *psin6;
  		struct sockaddr_storage ss;
  
  		psin6 = (struct sockaddr_in6 *)&ss;
  		memset(&ss, 0, sizeof(ss));
  		psin6->sin6_family = AF_INET6;
  		psin6->sin6_addr = psl->sl_addr[i];

  		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))

  			return -EFAULT;
  	}
  	return 0;
  done:
  	read_unlock_bh(&idev->lock);

  	rcu_read_unlock();

  	return err;
  }

  int inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
  		   const struct in6_addr *src_addr)

  {
  	struct ipv6_pinfo *np = inet6_sk(sk);
  	struct ipv6_mc_socklist *mc;
  	struct ip6_sf_socklist *psl;
  	int rv = 1;

  	rcu_read_lock();
  	for_each_pmc_rcu(np, mc) {

  		if (ipv6_addr_equal(&mc->addr, mc_addr))
  			break;
  	}
  	if (!mc) {

  		rcu_read_unlock();

  		return 1;
  	}

  	read_lock(&mc->sflock);

  	psl = mc->sflist;
  	if (!psl) {
  		rv = mc->sfmode == MCAST_EXCLUDE;
  	} else {
  		int i;
  
  		for (i=0; i<psl->sl_count; i++) {
  			if (ipv6_addr_equal(&psl->sl_addr[i], src_addr))
  				break;
  		}
  		if (mc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
  			rv = 0;
  		if (mc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
  			rv = 0;
  	}

  	read_unlock(&mc->sflock);

  	rcu_read_unlock();

  
  	return rv;
  }
  
  static void ma_put(struct ifmcaddr6 *mc)
  {
  	if (atomic_dec_and_test(&mc->mca_refcnt)) {
  		in6_dev_put(mc->idev);
  		kfree(mc);
  	}
  }
  
  static void igmp6_group_added(struct ifmcaddr6 *mc)
  {
  	struct net_device *dev = mc->idev->dev;
  	char buf[MAX_ADDR_LEN];
  
  	spin_lock_bh(&mc->mca_lock);
  	if (!(mc->mca_flags&MAF_LOADED)) {
  		mc->mca_flags |= MAF_LOADED;
  		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)

  			dev_mc_add(dev, buf);

  	}
  	spin_unlock_bh(&mc->mca_lock);
  
  	if (!(dev->flags & IFF_UP) || (mc->mca_flags & MAF_NOREPORT))
  		return;
  
  	if (MLD_V1_SEEN(mc->idev)) {
  		igmp6_join_group(mc);
  		return;
  	}
  	/* else v2 */
  
  	mc->mca_crcount = mc->idev->mc_qrv;
  	mld_ifc_event(mc->idev);
  }
  
  static void igmp6_group_dropped(struct ifmcaddr6 *mc)
  {
  	struct net_device *dev = mc->idev->dev;
  	char buf[MAX_ADDR_LEN];
  
  	spin_lock_bh(&mc->mca_lock);
  	if (mc->mca_flags&MAF_LOADED) {
  		mc->mca_flags &= ~MAF_LOADED;
  		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)

  			dev_mc_del(dev, buf);

  	}
  
  	if (mc->mca_flags & MAF_NOREPORT)
  		goto done;
  	spin_unlock_bh(&mc->mca_lock);
  
  	if (!mc->idev->dead)
  		igmp6_leave_group(mc);
  
  	spin_lock_bh(&mc->mca_lock);
  	if (del_timer(&mc->mca_timer))
  		atomic_dec(&mc->mca_refcnt);
  done:
  	ip6_mc_clear_src(mc);
  	spin_unlock_bh(&mc->mca_lock);
  }
  
  /*
   * deleted ifmcaddr6 manipulation
   */
  static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
  {
  	struct ifmcaddr6 *pmc;
  
  	/* this is an "ifmcaddr6" for convenience; only the fields below
  	 * are actually used. In particular, the refcnt and users are not
  	 * used for management of the delete list. Using the same structure
  	 * for deleted items allows change reports to use common code with
  	 * non-deleted or query-response MCA's.
  	 */

  	pmc = kzalloc(sizeof(*pmc), GFP_ATOMIC);

  	if (!pmc)
  		return;

  	spin_lock_bh(&im->mca_lock);
  	spin_lock_init(&pmc->mca_lock);
  	pmc->idev = im->idev;
  	in6_dev_hold(idev);
  	pmc->mca_addr = im->mca_addr;
  	pmc->mca_crcount = idev->mc_qrv;
  	pmc->mca_sfmode = im->mca_sfmode;
  	if (pmc->mca_sfmode == MCAST_INCLUDE) {
  		struct ip6_sf_list *psf;
  
  		pmc->mca_tomb = im->mca_tomb;
  		pmc->mca_sources = im->mca_sources;
  		im->mca_tomb = im->mca_sources = NULL;
  		for (psf=pmc->mca_sources; psf; psf=psf->sf_next)
  			psf->sf_crcount = pmc->mca_crcount;
  	}
  	spin_unlock_bh(&im->mca_lock);

  	spin_lock_bh(&idev->mc_lock);

  	pmc->next = idev->mc_tomb;
  	idev->mc_tomb = pmc;

  	spin_unlock_bh(&idev->mc_lock);

  }

  static void mld_del_delrec(struct inet6_dev *idev, const struct in6_addr *pmca)

  {
  	struct ifmcaddr6 *pmc, *pmc_prev;
  	struct ip6_sf_list *psf, *psf_next;

  	spin_lock_bh(&idev->mc_lock);

  	pmc_prev = NULL;
  	for (pmc=idev->mc_tomb; pmc; pmc=pmc->next) {
  		if (ipv6_addr_equal(&pmc->mca_addr, pmca))
  			break;
  		pmc_prev = pmc;
  	}
  	if (pmc) {
  		if (pmc_prev)
  			pmc_prev->next = pmc->next;
  		else
  			idev->mc_tomb = pmc->next;
  	}

  	spin_unlock_bh(&idev->mc_lock);

  	if (pmc) {
  		for (psf=pmc->mca_tomb; psf; psf=psf_next) {
  			psf_next = psf->sf_next;
  			kfree(psf);
  		}
  		in6_dev_put(pmc->idev);
  		kfree(pmc);
  	}
  }
  
  static void mld_clear_delrec(struct inet6_dev *idev)
  {
  	struct ifmcaddr6 *pmc, *nextpmc;

  	spin_lock_bh(&idev->mc_lock);

  	pmc = idev->mc_tomb;
  	idev->mc_tomb = NULL;

  	spin_unlock_bh(&idev->mc_lock);

  
  	for (; pmc; pmc = nextpmc) {
  		nextpmc = pmc->next;
  		ip6_mc_clear_src(pmc);
  		in6_dev_put(pmc->idev);
  		kfree(pmc);
  	}
  
  	/* clear dead sources, too */
  	read_lock_bh(&idev->lock);
  	for (pmc=idev->mc_list; pmc; pmc=pmc->next) {
  		struct ip6_sf_list *psf, *psf_next;
  
  		spin_lock_bh(&pmc->mca_lock);
  		psf = pmc->mca_tomb;
  		pmc->mca_tomb = NULL;
  		spin_unlock_bh(&pmc->mca_lock);
  		for (; psf; psf=psf_next) {
  			psf_next = psf->sf_next;
  			kfree(psf);
  		}
  	}
  	read_unlock_bh(&idev->lock);
  }
  
  
  /*
   *	device multicast group inc (add if not found)
   */

  int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr)

  {
  	struct ifmcaddr6 *mc;
  	struct inet6_dev *idev;

  	/* we need to take a reference on idev */

  	idev = in6_dev_get(dev);
  
  	if (idev == NULL)
  		return -EINVAL;
  
  	write_lock_bh(&idev->lock);
  	if (idev->dead) {
  		write_unlock_bh(&idev->lock);
  		in6_dev_put(idev);
  		return -ENODEV;
  	}
  
  	for (mc = idev->mc_list; mc; mc = mc->next) {
  		if (ipv6_addr_equal(&mc->mca_addr, addr)) {
  			mc->mca_users++;
  			write_unlock_bh(&idev->lock);
  			ip6_mc_add_src(idev, &mc->mca_addr, MCAST_EXCLUDE, 0,
  				NULL, 0);
  			in6_dev_put(idev);
  			return 0;
  		}
  	}
  
  	/*
  	 *	not found: create a new one.
  	 */

  	mc = kzalloc(sizeof(struct ifmcaddr6), GFP_ATOMIC);

  
  	if (mc == NULL) {
  		write_unlock_bh(&idev->lock);
  		in6_dev_put(idev);
  		return -ENOMEM;
  	}

  	setup_timer(&mc->mca_timer, igmp6_timer_handler, (unsigned long)mc);

  	mc->mca_addr = *addr;

  	mc->idev = idev; /* (reference taken) */

  	mc->mca_users = 1;
  	/* mca_stamp should be updated upon changes */
  	mc->mca_cstamp = mc->mca_tstamp = jiffies;
  	atomic_set(&mc->mca_refcnt, 2);
  	spin_lock_init(&mc->mca_lock);
  
  	/* initial mode is (EX, empty) */
  	mc->mca_sfmode = MCAST_EXCLUDE;
  	mc->mca_sfcount[MCAST_EXCLUDE] = 1;
  
  	if (ipv6_addr_is_ll_all_nodes(&mc->mca_addr) ||
  	    IPV6_ADDR_MC_SCOPE(&mc->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
  		mc->mca_flags |= MAF_NOREPORT;
  
  	mc->next = idev->mc_list;
  	idev->mc_list = mc;
  	write_unlock_bh(&idev->lock);
  
  	mld_del_delrec(idev, &mc->mca_addr);
  	igmp6_group_added(mc);
  	ma_put(mc);
  	return 0;
  }
  
  /*
   *	device multicast group del
   */

  int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr)

  {
  	struct ifmcaddr6 *ma, **map;
  
  	write_lock_bh(&idev->lock);
  	for (map = &idev->mc_list; (ma=*map) != NULL; map = &ma->next) {
  		if (ipv6_addr_equal(&ma->mca_addr, addr)) {
  			if (--ma->mca_users == 0) {
  				*map = ma->next;
  				write_unlock_bh(&idev->lock);
  
  				igmp6_group_dropped(ma);
  
  				ma_put(ma);
  				return 0;
  			}
  			write_unlock_bh(&idev->lock);
  			return 0;
  		}
  	}
  	write_unlock_bh(&idev->lock);
  
  	return -ENOENT;
  }

  int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)

  {

  	struct inet6_dev *idev;

  	int err;

  	rcu_read_lock();

  	idev = __in6_dev_get(dev);
  	if (!idev)
  		err = -ENODEV;
  	else
  		err = __ipv6_dev_mc_dec(idev, addr);

  	rcu_read_unlock();

  	return err;
  }
  
  /*
   * identify MLD packets for MLD filter exceptions
   */
  int ipv6_is_mld(struct sk_buff *skb, int nexthdr)
  {
  	struct icmp6hdr *pic;
  
  	if (nexthdr != IPPROTO_ICMPV6)
  		return 0;
  
  	if (!pskb_may_pull(skb, sizeof(struct icmp6hdr)))
  		return 0;

  	pic = icmp6_hdr(skb);

  
  	switch (pic->icmp6_type) {
  	case ICMPV6_MGM_QUERY:
  	case ICMPV6_MGM_REPORT:
  	case ICMPV6_MGM_REDUCTION:
  	case ICMPV6_MLD2_REPORT:
  		return 1;
  	default:
  		break;
  	}
  	return 0;
  }
  
  /*
   *	check if the interface/address pair is valid
   */

  int ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
  			const struct in6_addr *src_addr)

  {
  	struct inet6_dev *idev;
  	struct ifmcaddr6 *mc;
  	int rv = 0;

  	rcu_read_lock();
  	idev = __in6_dev_get(dev);

  	if (idev) {
  		read_lock_bh(&idev->lock);
  		for (mc = idev->mc_list; mc; mc=mc->next) {
  			if (ipv6_addr_equal(&mc->mca_addr, group))
  				break;
  		}
  		if (mc) {
  			if (src_addr && !ipv6_addr_any(src_addr)) {
  				struct ip6_sf_list *psf;
  
  				spin_lock_bh(&mc->mca_lock);
  				for (psf=mc->mca_sources;psf;psf=psf->sf_next) {
  					if (ipv6_addr_equal(&psf->sf_addr, src_addr))
  						break;
  				}
  				if (psf)
  					rv = psf->sf_count[MCAST_INCLUDE] ||
  						psf->sf_count[MCAST_EXCLUDE] !=
  						mc->mca_sfcount[MCAST_EXCLUDE];
  				else
  					rv = mc->mca_sfcount[MCAST_EXCLUDE] !=0;
  				spin_unlock_bh(&mc->mca_lock);
  			} else
  				rv = 1; /* don't filter unspecified source */
  		}
  		read_unlock_bh(&idev->lock);

  	}

  	rcu_read_unlock();

  	return rv;
  }
  
  static void mld_gq_start_timer(struct inet6_dev *idev)
  {
  	int tv = net_random() % idev->mc_maxdelay;
  
  	idev->mc_gq_running = 1;
  	if (!mod_timer(&idev->mc_gq_timer, jiffies+tv+2))
  		in6_dev_hold(idev);
  }
  
  static void mld_ifc_start_timer(struct inet6_dev *idev, int delay)
  {
  	int tv = net_random() % delay;
  
  	if (!mod_timer(&idev->mc_ifc_timer, jiffies+tv+2))
  		in6_dev_hold(idev);
  }
  
  /*
   *	IGMP handling (alias multicast ICMPv6 messages)
   */
  
  static void igmp6_group_queried(struct ifmcaddr6 *ma, unsigned long resptime)
  {
  	unsigned long delay = resptime;
  
  	/* Do not start timer for these addresses */
  	if (ipv6_addr_is_ll_all_nodes(&ma->mca_addr) ||
  	    IPV6_ADDR_MC_SCOPE(&ma->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
  		return;
  
  	if (del_timer(&ma->mca_timer)) {
  		atomic_dec(&ma->mca_refcnt);
  		delay = ma->mca_timer.expires - jiffies;
  	}
  
  	if (delay >= resptime) {
  		if (resptime)
  			delay = net_random() % resptime;
  		else
  			delay = 1;
  	}
  	ma->mca_timer.expires = jiffies + delay;
  	if (!mod_timer(&ma->mca_timer, jiffies + delay))
  		atomic_inc(&ma->mca_refcnt);
  	ma->mca_flags |= MAF_TIMER_RUNNING;
  }

  /* mark EXCLUDE-mode sources */
  static int mld_xmarksources(struct ifmcaddr6 *pmc, int nsrcs,

  	const struct in6_addr *srcs)

  {
  	struct ip6_sf_list *psf;
  	int i, scount;
  
  	scount = 0;
  	for (psf=pmc->mca_sources; psf; psf=psf->sf_next) {
  		if (scount == nsrcs)
  			break;

  		for (i=0; i<nsrcs; i++) {
  			/* skip inactive filters */

  			if (psf->sf_count[MCAST_INCLUDE] ||

  			    pmc->mca_sfcount[MCAST_EXCLUDE] !=
  			    psf->sf_count[MCAST_EXCLUDE])
  				continue;
  			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
  				scount++;
  				break;
  			}
  		}
  	}
  	pmc->mca_flags &= ~MAF_GSQUERY;
  	if (scount == nsrcs)	/* all sources excluded */
  		return 0;
  	return 1;
  }
  
  static int mld_marksources(struct ifmcaddr6 *pmc, int nsrcs,

  	const struct in6_addr *srcs)

  {
  	struct ip6_sf_list *psf;
  	int i, scount;
  
  	if (pmc->mca_sfmode == MCAST_EXCLUDE)
  		return mld_xmarksources(pmc, nsrcs, srcs);
  
  	/* mark INCLUDE-mode sources */
  
  	scount = 0;
  	for (psf=pmc->mca_sources; psf; psf=psf->sf_next) {
  		if (scount == nsrcs)
  			break;
  		for (i=0; i<nsrcs; i++) {

  			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
  				psf->sf_gsresp = 1;
  				scount++;
  				break;
  			}

  		}
  	}
  	if (!scount) {
  		pmc->mca_flags &= ~MAF_GSQUERY;
  		return 0;

  	}

  	pmc->mca_flags |= MAF_GSQUERY;
  	return 1;

  }

  /* called with rcu_read_lock() */

  int igmp6_event_query(struct sk_buff *skb)
  {

  	struct mld2_query *mlh2 = NULL;

  	struct ifmcaddr6 *ma;

  	const struct in6_addr *group;

  	unsigned long max_delay;
  	struct inet6_dev *idev;

  	struct mld_msg *mld;

  	int group_type;
  	int mark = 0;
  	int len;
  
  	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
  		return -EINVAL;
  
  	/* compute payload length excluding extension headers */

  	len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);

  	len -= skb_network_header_len(skb);

  
  	/* Drop queries with not link local source */

  	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL))

  		return -EINVAL;

  	idev = __in6_dev_get(skb->dev);

  
  	if (idev == NULL)
  		return 0;

  	mld = (struct mld_msg *)icmp6_hdr(skb);
  	group = &mld->mld_mca;

  	group_type = ipv6_addr_type(group);
  
  	if (group_type != IPV6_ADDR_ANY &&

  	    !(group_type&IPV6_ADDR_MULTICAST))

  		return -EINVAL;

  
  	if (len == 24) {
  		int switchback;
  		/* MLDv1 router present */
  
  		/* Translate milliseconds to jiffies */

  		max_delay = (ntohs(mld->mld_maxdelay)*HZ)/1000;

  
  		switchback = (idev->mc_qrv + 1) * max_delay;
  		idev->mc_v1_seen = jiffies + switchback;
  
  		/* cancel the interface change timer */
  		idev->mc_ifc_count = 0;
  		if (del_timer(&idev->mc_ifc_timer))
  			__in6_dev_put(idev);
  		/* clear deleted report items */
  		mld_clear_delrec(idev);
  	} else if (len >= 28) {

  		int srcs_offset = sizeof(struct mld2_query) -

  				  sizeof(struct icmp6hdr);

  		if (!pskb_may_pull(skb, srcs_offset))

  			return -EINVAL;

  		mlh2 = (struct mld2_query *)skb_transport_header(skb);

  		max_delay = (MLDV2_MRC(ntohs(mlh2->mld2q_mrc))*HZ)/1000;

  		if (!max_delay)
  			max_delay = 1;
  		idev->mc_maxdelay = max_delay;

  		if (mlh2->mld2q_qrv)
  			idev->mc_qrv = mlh2->mld2q_qrv;

  		if (group_type == IPV6_ADDR_ANY) { /* general query */

  			if (mlh2->mld2q_nsrcs)

  				return -EINVAL; /* no sources allowed */

  			mld_gq_start_timer(idev);

  			return 0;
  		}
  		/* mark sources to include, if group & source-specific */

  		if (mlh2->mld2q_nsrcs != 0) {

  			if (!pskb_may_pull(skb, srcs_offset +

  			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))

  				return -EINVAL;

  			mlh2 = (struct mld2_query *)skb_transport_header(skb);

  			mark = 1;
  		}

  	} else

  		return -EINVAL;

  
  	read_lock_bh(&idev->lock);
  	if (group_type == IPV6_ADDR_ANY) {
  		for (ma = idev->mc_list; ma; ma=ma->next) {
  			spin_lock_bh(&ma->mca_lock);
  			igmp6_group_queried(ma, max_delay);
  			spin_unlock_bh(&ma->mca_lock);
  		}
  	} else {
  		for (ma = idev->mc_list; ma; ma=ma->next) {

  			if (!ipv6_addr_equal(group, &ma->mca_addr))

  				continue;
  			spin_lock_bh(&ma->mca_lock);
  			if (ma->mca_flags & MAF_TIMER_RUNNING) {
  				/* gsquery <- gsquery && mark */
  				if (!mark)
  					ma->mca_flags &= ~MAF_GSQUERY;
  			} else {
  				/* gsquery <- mark */
  				if (mark)
  					ma->mca_flags |= MAF_GSQUERY;
  				else
  					ma->mca_flags &= ~MAF_GSQUERY;
  			}

  			if (!(ma->mca_flags & MAF_GSQUERY) ||

  			    mld_marksources(ma, ntohs(mlh2->mld2q_nsrcs), mlh2->mld2q_srcs))

  				igmp6_group_queried(ma, max_delay);

  			spin_unlock_bh(&ma->mca_lock);

  			break;

  		}
  	}
  	read_unlock_bh(&idev->lock);

  
  	return 0;
  }

  /* called with rcu_read_lock() */

  int igmp6_event_report(struct sk_buff *skb)
  {
  	struct ifmcaddr6 *ma;

  	struct inet6_dev *idev;

  	struct mld_msg *mld;

  	int addr_type;
  
  	/* Our own report looped back. Ignore it. */
  	if (skb->pkt_type == PACKET_LOOPBACK)
  		return 0;

  	/* send our report if the MC router may not have heard this report */
  	if (skb->pkt_type != PACKET_MULTICAST &&
  	    skb->pkt_type != PACKET_BROADCAST)
  		return 0;

  	if (!pskb_may_pull(skb, sizeof(*mld) - sizeof(struct icmp6hdr)))

  		return -EINVAL;

  	mld = (struct mld_msg *)icmp6_hdr(skb);

  
  	/* Drop reports with not link local source */

  	addr_type = ipv6_addr_type(&ipv6_hdr(skb)->saddr);

  	if (addr_type != IPV6_ADDR_ANY &&

  	    !(addr_type&IPV6_ADDR_LINKLOCAL))
  		return -EINVAL;

  	idev = __in6_dev_get(skb->dev);

  	if (idev == NULL)
  		return -ENODEV;
  
  	/*
  	 *	Cancel the timer for this group
  	 */
  
  	read_lock_bh(&idev->lock);
  	for (ma = idev->mc_list; ma; ma=ma->next) {

  		if (ipv6_addr_equal(&ma->mca_addr, &mld->mld_mca)) {

  			spin_lock(&ma->mca_lock);
  			if (del_timer(&ma->mca_timer))
  				atomic_dec(&ma->mca_refcnt);
  			ma->mca_flags &= ~(MAF_LAST_REPORTER|MAF_TIMER_RUNNING);
  			spin_unlock(&ma->mca_lock);
  			break;
  		}
  	}
  	read_unlock_bh(&idev->lock);

  	return 0;
  }
  
  static int is_in(struct ifmcaddr6 *pmc, struct ip6_sf_list *psf, int type,
  	int gdeleted, int sdeleted)
  {
  	switch (type) {
  	case MLD2_MODE_IS_INCLUDE:
  	case MLD2_MODE_IS_EXCLUDE:
  		if (gdeleted || sdeleted)
  			return 0;

  		if (!((pmc->mca_flags & MAF_GSQUERY) && !psf->sf_gsresp)) {
  			if (pmc->mca_sfmode == MCAST_INCLUDE)
  				return 1;
  			/* don't include if this source is excluded
  			 * in all filters
  			 */
  			if (psf->sf_count[MCAST_INCLUDE])

  				return type == MLD2_MODE_IS_INCLUDE;

  			return pmc->mca_sfcount[MCAST_EXCLUDE] ==
  				psf->sf_count[MCAST_EXCLUDE];
  		}
  		return 0;

  	case MLD2_CHANGE_TO_INCLUDE:
  		if (gdeleted || sdeleted)
  			return 0;
  		return psf->sf_count[MCAST_INCLUDE] != 0;
  	case MLD2_CHANGE_TO_EXCLUDE:
  		if (gdeleted || sdeleted)
  			return 0;
  		if (pmc->mca_sfcount[MCAST_EXCLUDE] == 0 ||
  		    psf->sf_count[MCAST_INCLUDE])
  			return 0;
  		return pmc->mca_sfcount[MCAST_EXCLUDE] ==
  			psf->sf_count[MCAST_EXCLUDE];
  	case MLD2_ALLOW_NEW_SOURCES:
  		if (gdeleted || !psf->sf_crcount)
  			return 0;
  		return (pmc->mca_sfmode == MCAST_INCLUDE) ^ sdeleted;
  	case MLD2_BLOCK_OLD_SOURCES:
  		if (pmc->mca_sfmode == MCAST_INCLUDE)
  			return gdeleted || (psf->sf_crcount && sdeleted);
  		return psf->sf_crcount && !gdeleted && !sdeleted;
  	}
  	return 0;
  }
  
  static int
  mld_scount(struct ifmcaddr6 *pmc, int type, int gdeleted, int sdeleted)
  {
  	struct ip6_sf_list *psf;
  	int scount = 0;
  
  	for (psf=pmc->mca_sources; psf; psf=psf->sf_next) {
  		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
  			continue;
  		scount++;
  	}
  	return scount;
  }
  
  static struct sk_buff *mld_newpack(struct net_device *dev, int size)
  {

  	struct net *net = dev_net(dev);

  	struct sock *sk = net->ipv6.igmp_sk;

  	struct sk_buff *skb;
  	struct mld2_report *pmr;
  	struct in6_addr addr_buf;

  	const struct in6_addr *saddr;

  	int hlen = LL_RESERVED_SPACE(dev);
  	int tlen = dev->needed_tailroom;

  	int err;
  	u8 ra[8] = { IPPROTO_ICMPV6, 0,
  		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
  		     IPV6_TLV_PADN, 0 };
  
  	/* we assume size > sizeof(ra) here */

  	size += hlen + tlen;

  	/* limit our allocations to order-0 page */
  	size = min_t(int, size, SKB_MAX_ORDER(0, 0));
  	skb = sock_alloc_send_skb(sk, size, 1, &err);

  	if (!skb)

  		return NULL;

  	skb_reserve(skb, hlen);

  	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {

  		/* <draft-ietf-magma-mld-source-05.txt>:

  		 * use unspecified address as the source address

  		 * when a valid link-local address is not available.
  		 */

  		saddr = &in6addr_any;
  	} else
  		saddr = &addr_buf;

  	ip6_nd_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);

  
  	memcpy(skb_put(skb, sizeof(ra)), ra, sizeof(ra));

  	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);

  	skb_put(skb, sizeof(*pmr));
  	pmr = (struct mld2_report *)skb_transport_header(skb);

  	pmr->mld2r_type = ICMPV6_MLD2_REPORT;
  	pmr->mld2r_resv1 = 0;
  	pmr->mld2r_cksum = 0;
  	pmr->mld2r_resv2 = 0;
  	pmr->mld2r_ngrec = 0;

  	return skb;
  }
  
  static void mld_sendpack(struct sk_buff *skb)
  {

  	struct ipv6hdr *pip6 = ipv6_hdr(skb);

  	struct mld2_report *pmr =
  			      (struct mld2_report *)skb_transport_header(skb);

  	int payload_len, mldlen;

  	struct inet6_dev *idev;

  	struct net *net = dev_net(skb->dev);

  	int err;

  	struct flowi6 fl6;

  	struct dst_entry *dst;

  	rcu_read_lock();
  	idev = __in6_dev_get(skb->dev);

  	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);

  	payload_len = (skb->tail - skb->network_header) - sizeof(*pip6);
  	mldlen = skb->tail - skb->transport_header;

  	pip6->payload_len = htons(payload_len);

  	pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
  					   IPPROTO_ICMPV6,
  					   csum_partial(skb_transport_header(skb),
  							mldlen, 0));

  	icmpv6_flow_init(net->ipv6.igmp_sk, &fl6, ICMPV6_MLD2_REPORT,

  			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
  			 skb->dev->ifindex);

  	dst = icmp6_dst_alloc(skb->dev, NULL, &fl6);

  	err = 0;
  	if (IS_ERR(dst)) {
  		err = PTR_ERR(dst);
  		dst = NULL;
  	}

  	skb_dst_set(skb, dst);

  	if (err)
  		goto err_out;

  	payload_len = skb->len;

  	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL, skb->dev,

  		      dst_output);
  out:

  	if (!err) {

  		ICMP6MSGOUT_INC_STATS_BH(net, idev, ICMPV6_MLD2_REPORT);

  		ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTMSGS);

  		IP6_UPD_PO_STATS_BH(net, idev, IPSTATS_MIB_OUTMCAST, payload_len);

  	} else

  		IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_OUTDISCARDS);

  	rcu_read_unlock();

  	return;
  
  err_out:
  	kfree_skb(skb);
  	goto out;

  }
  
  static int grec_size(struct ifmcaddr6 *pmc, int type, int gdel, int sdel)
  {

  	return sizeof(struct mld2_grec) + 16 * mld_scount(pmc,type,gdel,sdel);

  }
  
  static struct sk_buff *add_grhead(struct sk_buff *skb, struct ifmcaddr6 *pmc,
  	int type, struct mld2_grec **ppgr)
  {
  	struct net_device *dev = pmc->idev->dev;
  	struct mld2_report *pmr;
  	struct mld2_grec *pgr;
  
  	if (!skb)
  		skb = mld_newpack(dev, dev->mtu);
  	if (!skb)
  		return NULL;
  	pgr = (struct mld2_grec *)skb_put(skb, sizeof(struct mld2_grec));
  	pgr->grec_type = type;
  	pgr->grec_auxwords = 0;
  	pgr->grec_nsrcs = 0;
  	pgr->grec_mca = pmc->mca_addr;	/* structure copy */

  	pmr = (struct mld2_report *)skb_transport_header(skb);

  	pmr->mld2r_ngrec = htons(ntohs(pmr->mld2r_ngrec)+1);

  	*ppgr = pgr;
  	return skb;
  }
  
  #define AVAILABLE(skb) ((skb) ? ((skb)->dev ? (skb)->dev->mtu - (skb)->len : \
  	skb_tailroom(skb)) : 0)
  
  static struct sk_buff *add_grec(struct sk_buff *skb, struct ifmcaddr6 *pmc,
  	int type, int gdeleted, int sdeleted)
  {
  	struct net_device *dev = pmc->idev->dev;
  	struct mld2_report *pmr;
  	struct mld2_grec *pgr = NULL;
  	struct ip6_sf_list *psf, *psf_next, *psf_prev, **psf_list;

  	int scount, stotal, first, isquery, truncate;

  
  	if (pmc->mca_flags & MAF_NOREPORT)
  		return skb;
  
  	isquery = type == MLD2_MODE_IS_INCLUDE ||
  		  type == MLD2_MODE_IS_EXCLUDE;
  	truncate = type == MLD2_MODE_IS_EXCLUDE ||
  		    type == MLD2_CHANGE_TO_EXCLUDE;

  	stotal = scount = 0;

  	psf_list = sdeleted ? &pmc->mca_tomb : &pmc->mca_sources;

  	if (!*psf_list)
  		goto empty_source;

  	pmr = skb ? (struct mld2_report *)skb_transport_header(skb) : NULL;

  
  	/* EX and TO_EX get a fresh packet, if needed */
  	if (truncate) {

  		if (pmr && pmr->mld2r_ngrec &&

  		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
  			if (skb)
  				mld_sendpack(skb);
  			skb = mld_newpack(dev, dev->mtu);
  		}
  	}
  	first = 1;

  	psf_prev = NULL;
  	for (psf=*psf_list; psf; psf=psf_next) {
  		struct in6_addr *psrc;
  
  		psf_next = psf->sf_next;
  
  		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
  			psf_prev = psf;
  			continue;
  		}
  
  		/* clear marks on query responses */
  		if (isquery)
  			psf->sf_gsresp = 0;
  
  		if (AVAILABLE(skb) < sizeof(*psrc) +
  		    first*sizeof(struct mld2_grec)) {
  			if (truncate && !first)
  				break;	 /* truncate these */
  			if (pgr)
  				pgr->grec_nsrcs = htons(scount);
  			if (skb)
  				mld_sendpack(skb);
  			skb = mld_newpack(dev, dev->mtu);
  			first = 1;
  			scount = 0;
  		}
  		if (first) {
  			skb = add_grhead(skb, pmc, type, &pgr);
  			first = 0;
  		}

  		if (!skb)
  			return NULL;

  		psrc = (struct in6_addr *)skb_put(skb, sizeof(*psrc));
  		*psrc = psf->sf_addr;

  		scount++; stotal++;

  		if ((type == MLD2_ALLOW_NEW_SOURCES ||
  		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
  			psf->sf_crcount--;
  			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
  				if (psf_prev)
  					psf_prev->sf_next = psf->sf_next;
  				else
  					*psf_list = psf->sf_next;
  				kfree(psf);
  				continue;
  			}
  		}
  		psf_prev = psf;
  	}

  
  empty_source:
  	if (!stotal) {
  		if (type == MLD2_ALLOW_NEW_SOURCES ||
  		    type == MLD2_BLOCK_OLD_SOURCES)
  			return skb;
  		if (pmc->mca_crcount || isquery) {
  			/* make sure we have room for group header */
  			if (skb && AVAILABLE(skb) < sizeof(struct mld2_grec)) {
  				mld_sendpack(skb);
  				skb = NULL; /* add_grhead will get a new one */
  			}
  			skb = add_grhead(skb, pmc, type, &pgr);
  		}
  	}

  	if (pgr)
  		pgr->grec_nsrcs = htons(scount);
  
  	if (isquery)
  		pmc->mca_flags &= ~MAF_GSQUERY;	/* clear query state */
  	return skb;
  }
  
  static void mld_send_report(struct inet6_dev *idev, struct ifmcaddr6 *pmc)
  {
  	struct sk_buff *skb = NULL;
  	int type;
  
  	if (!pmc) {
  		read_lock_bh(&idev->lock);
  		for (pmc=idev->mc_list; pmc; pmc=pmc->next) {
  			if (pmc->mca_flags & MAF_NOREPORT)
  				continue;
  			spin_lock_bh(&pmc->mca_lock);
  			if (pmc->mca_sfcount[MCAST_EXCLUDE])
  				type = MLD2_MODE_IS_EXCLUDE;
  			else
  				type = MLD2_MODE_IS_INCLUDE;
  			skb = add_grec(skb, pmc, type, 0, 0);
  			spin_unlock_bh(&pmc->mca_lock);
  		}
  		read_unlock_bh(&idev->lock);
  	} else {
  		spin_lock_bh(&pmc->mca_lock);
  		if (pmc->mca_sfcount[MCAST_EXCLUDE])
  			type = MLD2_MODE_IS_EXCLUDE;
  		else
  			type = MLD2_MODE_IS_INCLUDE;
  		skb = add_grec(skb, pmc, type, 0, 0);
  		spin_unlock_bh(&pmc->mca_lock);
  	}
  	if (skb)
  		mld_sendpack(skb);
  }
  
  /*
   * remove zero-count source records from a source filter list
   */
  static void mld_clear_zeros(struct ip6_sf_list **ppsf)
  {
  	struct ip6_sf_list *psf_prev, *psf_next, *psf;
  
  	psf_prev = NULL;
  	for (psf=*ppsf; psf; psf = psf_next) {
  		psf_next = psf->sf_next;
  		if (psf->sf_crcount == 0) {
  			if (psf_prev)
  				psf_prev->sf_next = psf->sf_next;
  			else
  				*ppsf = psf->sf_next;
  			kfree(psf);
  		} else
  			psf_prev = psf;
  	}
  }
  
  static void mld_send_cr(struct inet6_dev *idev)
  {
  	struct ifmcaddr6 *pmc, *pmc_prev, *pmc_next;
  	struct sk_buff *skb = NULL;
  	int type, dtype;
  
  	read_lock_bh(&idev->lock);

  	spin_lock(&idev->mc_lock);

  
  	/* deleted MCA's */
  	pmc_prev = NULL;
  	for (pmc=idev->mc_tomb; pmc; pmc=pmc_next) {
  		pmc_next = pmc->next;
  		if (pmc->mca_sfmode == MCAST_INCLUDE) {
  			type = MLD2_BLOCK_OLD_SOURCES;
  			dtype = MLD2_BLOCK_OLD_SOURCES;
  			skb = add_grec(skb, pmc, type, 1, 0);
  			skb = add_grec(skb, pmc, dtype, 1, 1);
  		}
  		if (pmc->mca_crcount) {

  			if (pmc->mca_sfmode == MCAST_EXCLUDE) {
  				type = MLD2_CHANGE_TO_INCLUDE;
  				skb = add_grec(skb, pmc, type, 1, 0);
  			}

  			pmc->mca_crcount--;

  			if (pmc->mca_crcount == 0) {
  				mld_clear_zeros(&pmc->mca_tomb);
  				mld_clear_zeros(&pmc->mca_sources);
  			}
  		}
  		if (pmc->mca_crcount == 0 && !pmc->mca_tomb &&
  		    !pmc->mca_sources) {
  			if (pmc_prev)
  				pmc_prev->next = pmc_next;
  			else
  				idev->mc_tomb = pmc_next;
  			in6_dev_put(pmc->idev);
  			kfree(pmc);
  		} else
  			pmc_prev = pmc;
  	}

  	spin_unlock(&idev->mc_lock);

  
  	/* change recs */
  	for (pmc=idev->mc_list; pmc; pmc=pmc->next) {
  		spin_lock_bh(&pmc->mca_lock);
  		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
  			type = MLD2_BLOCK_OLD_SOURCES;
  			dtype = MLD2_ALLOW_NEW_SOURCES;
  		} else {
  			type = MLD2_ALLOW_NEW_SOURCES;
  			dtype = MLD2_BLOCK_OLD_SOURCES;
  		}
  		skb = add_grec(skb, pmc, type, 0, 0);
  		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
  
  		/* filter mode changes */
  		if (pmc->mca_crcount) {

  			if (pmc->mca_sfmode == MCAST_EXCLUDE)
  				type = MLD2_CHANGE_TO_EXCLUDE;
  			else
  				type = MLD2_CHANGE_TO_INCLUDE;
  			skb = add_grec(skb, pmc, type, 0, 0);

  			pmc->mca_crcount--;

  		}
  		spin_unlock_bh(&pmc->mca_lock);
  	}
  	read_unlock_bh(&idev->lock);
  	if (!skb)
  		return;
  	(void) mld_sendpack(skb);
  }
  
  static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
  {

  	struct net *net = dev_net(dev);

  	struct sock *sk = net->ipv6.igmp_sk;

  	struct inet6_dev *idev;

  	struct sk_buff *skb;

  	struct mld_msg *hdr;

  	const struct in6_addr *snd_addr, *saddr;

  	struct in6_addr addr_buf;

  	int hlen = LL_RESERVED_SPACE(dev);
  	int tlen = dev->needed_tailroom;

  	int err, len, payload_len, full_len;
  	u8 ra[8] = { IPPROTO_ICMPV6, 0,
  		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
  		     IPV6_TLV_PADN, 0 };

  	struct flowi6 fl6;

  	struct dst_entry *dst;

  	if (type == ICMPV6_MGM_REDUCTION)
  		snd_addr = &in6addr_linklocal_allrouters;
  	else
  		snd_addr = addr;

  
  	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
  	payload_len = len + sizeof(ra);
  	full_len = sizeof(struct ipv6hdr) + payload_len;

  	rcu_read_lock();
  	IP6_UPD_PO_STATS(net, __in6_dev_get(dev),
  		      IPSTATS_MIB_OUT, full_len);
  	rcu_read_unlock();

  	skb = sock_alloc_send_skb(sk, hlen + tlen + full_len, 1, &err);

  
  	if (skb == NULL) {

  		rcu_read_lock();

  		IP6_INC_STATS(net, __in6_dev_get(dev),

  			      IPSTATS_MIB_OUTDISCARDS);
  		rcu_read_unlock();

  		return;
  	}

  	skb_reserve(skb, hlen);

  	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {

  		/* <draft-ietf-magma-mld-source-05.txt>:

  		 * use unspecified address as the source address

  		 * when a valid link-local address is not available.
  		 */

  		saddr = &in6addr_any;
  	} else
  		saddr = &addr_buf;

  	ip6_nd_hdr(sk, skb, dev, saddr, snd_addr, NEXTHDR_HOP, payload_len);

  
  	memcpy(skb_put(skb, sizeof(ra)), ra, sizeof(ra));

  	hdr = (struct mld_msg *) skb_put(skb, sizeof(struct mld_msg));
  	memset(hdr, 0, sizeof(struct mld_msg));
  	hdr->mld_type = type;

  	hdr->mld_mca = *addr;

  	hdr->mld_cksum = csum_ipv6_magic(saddr, snd_addr, len,
  					 IPPROTO_ICMPV6,
  					 csum_partial(hdr, len, 0));

  	rcu_read_lock();
  	idev = __in6_dev_get(skb->dev);

  	icmpv6_flow_init(sk, &fl6, type,

  			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
  			 skb->dev->ifindex);

  	dst = icmp6_dst_alloc(skb->dev, NULL, &fl6);

  	if (IS_ERR(dst)) {
  		err = PTR_ERR(dst);

  		goto err_out;

  	}

  	skb_dst_set(skb, dst);

  	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL, skb->dev,

  		      dst_output);
  out:

  	if (!err) {

  		ICMP6MSGOUT_INC_STATS(net, idev, type);

  		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);

  		IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUTMCAST, full_len);

  	} else

  		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);

  	rcu_read_unlock();

  	return;

  
  err_out:
  	kfree_skb(skb);
  	goto out;

  }
  
  static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,

  	const struct in6_addr *psfsrc)

  {
  	struct ip6_sf_list *psf, *psf_prev;
  	int rv = 0;
  
  	psf_prev = NULL;
  	for (psf=pmc->mca_sources; psf; psf=psf->sf_next) {
  		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
  			break;
  		psf_prev = psf;
  	}
  	if (!psf || psf->sf_count[sfmode] == 0) {
  		/* source filter not found, or count wrong =>  bug */
  		return -ESRCH;
  	}
  	psf->sf_count[sfmode]--;
  	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
  		struct inet6_dev *idev = pmc->idev;
  
  		/* no more filters for this source */
  		if (psf_prev)
  			psf_prev->sf_next = psf->sf_next;
  		else
  			pmc->mca_sources = psf->sf_next;
  		if (psf->sf_oldin && !(pmc->mca_flags & MAF_NOREPORT) &&
  		    !MLD_V1_SEEN(idev)) {
  			psf->sf_crcount = idev->mc_qrv;
  			psf->sf_next = pmc->mca_tomb;
  			pmc->mca_tomb = psf;
  			rv = 1;
  		} else
  			kfree(psf);
  	}
  	return rv;
  }

  static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
  			  int sfmode, int sfcount, const struct in6_addr *psfsrc,

  			  int delta)
  {
  	struct ifmcaddr6 *pmc;
  	int	changerec = 0;
  	int	i, err;
  
  	if (!idev)
  		return -ENODEV;
  	read_lock_bh(&idev->lock);
  	for (pmc=idev->mc_list; pmc; pmc=pmc->next) {
  		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
  			break;
  	}
  	if (!pmc) {
  		/* MCA not found?? bug */
  		read_unlock_bh(&idev->lock);
  		return -ESRCH;
  	}
  	spin_lock_bh(&pmc->mca_lock);
  	sf_markstate(pmc);
  	if (!delta) {
  		if (!pmc->mca_sfcount[sfmode]) {
  			spin_unlock_bh(&pmc->mca_lock);
  			read_unlock_bh(&idev->lock);
  			return -EINVAL;
  		}
  		pmc->mca_sfcount[sfmode]--;
  	}
  	err = 0;
  	for (i=0; i<sfcount; i++) {
  		int rv = ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
  
  		changerec |= rv > 0;
  		if (!err && rv < 0)
  			err = rv;
  	}
  	if (pmc->mca_sfmode == MCAST_EXCLUDE &&
  	    pmc->mca_sfcount[MCAST_EXCLUDE] == 0 &&
  	    pmc->mca_sfcount[MCAST_INCLUDE]) {
  		struct ip6_sf_list *psf;
  
  		/* filter mode change */
  		pmc->mca_sfmode = MCAST_INCLUDE;
  		pmc->mca_crcount = idev->mc_qrv;
  		idev->mc_ifc_count = pmc->mca_crcount;
  		for (psf=pmc->mca_sources; psf; psf = psf->sf_next)
  			psf->sf_crcount = 0;
  		mld_ifc_event(pmc->idev);
  	} else if (sf_setstate(pmc) || changerec)
  		mld_ifc_event(pmc->idev);
  	spin_unlock_bh(&pmc->mca_lock);
  	read_unlock_bh(&idev->lock);
  	return err;
  }
  
  /*
   * Add multicast single-source filter to the interface list
   */
  static int ip6_mc_add1_src(struct ifmcaddr6 *pmc, int sfmode,

  	const struct in6_addr *psfsrc)

  {
  	struct ip6_sf_list *psf, *psf_prev;
  
  	psf_prev = NULL;
  	for (psf=pmc->mca_sources; psf; psf=psf->sf_next) {
  		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
  			break;
  		psf_prev = psf;
  	}
  	if (!psf) {

  		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);

  		if (!psf)
  			return -ENOBUFS;

  		psf->sf_addr = *psfsrc;
  		if (psf_prev) {
  			psf_prev->sf_next = psf;
  		} else
  			pmc->mca_sources = psf;
  	}
  	psf->sf_count[sfmode]++;
  	return 0;
  }
  
  static void sf_markstate(struct ifmcaddr6 *pmc)
  {
  	struct ip6_sf_list *psf;
  	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
  
  	for (psf=pmc->mca_sources; psf; psf=psf->sf_next)
  		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
  			psf->sf_oldin = mca_xcount ==
  				psf->sf_count[MCAST_EXCLUDE] &&
  				!psf->sf_count[MCAST_INCLUDE];
  		} else
  			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
  }
  
  static int sf_setstate(struct ifmcaddr6 *pmc)
  {

  	struct ip6_sf_list *psf, *dpsf;

  	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
  	int qrv = pmc->idev->mc_qrv;
  	int new_in, rv;
  
  	rv = 0;
  	for (psf=pmc->mca_sources; psf; psf=psf->sf_next) {
  		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
  			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
  				!psf->sf_count[MCAST_INCLUDE];
  		} else
  			new_in = psf->sf_count[MCAST_INCLUDE] != 0;

  		if (new_in) {
  			if (!psf->sf_oldin) {

  				struct ip6_sf_list *prev = NULL;

  
  				for (dpsf=pmc->mca_tomb; dpsf;
  				     dpsf=dpsf->sf_next) {
  					if (ipv6_addr_equal(&dpsf->sf_addr,
  					    &psf->sf_addr))
  						break;
  					prev = dpsf;
  				}
  				if (dpsf) {
  					if (prev)
  						prev->sf_next = dpsf->sf_next;
  					else
  						pmc->mca_tomb = dpsf->sf_next;
  					kfree(dpsf);
  				}
  				psf->sf_crcount = qrv;
  				rv++;
  			}
  		} else if (psf->sf_oldin) {
  			psf->sf_crcount = 0;
  			/*
  			 * add or update "delete" records if an active filter
  			 * is now inactive
  			 */
  			for (dpsf=pmc->mca_tomb; dpsf; dpsf=dpsf->sf_next)
  				if (ipv6_addr_equal(&dpsf->sf_addr,
  				    &psf->sf_addr))
  					break;
  			if (!dpsf) {

  				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);

  				if (!dpsf)
  					continue;
  				*dpsf = *psf;
  				/* pmc->mca_lock held by callers */
  				dpsf->sf_next = pmc->mca_tomb;
  				pmc->mca_tomb = dpsf;
  			}
  			dpsf->sf_crcount = qrv;

  			rv++;
  		}
  	}
  	return rv;
  }
  
  /*
   * Add multicast source filter list to the interface list
   */

  static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
  			  int sfmode, int sfcount, const struct in6_addr *psfsrc,

  			  int delta)
  {
  	struct ifmcaddr6 *pmc;
  	int	isexclude;
  	int	i, err;
  
  	if (!idev)
  		return -ENODEV;
  	read_lock_bh(&idev->lock);
  	for (pmc=idev->mc_list; pmc; pmc=pmc->next) {
  		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
  			break;
  	}
  	if (!pmc) {
  		/* MCA not found?? bug */
  		read_unlock_bh(&idev->lock);
  		return -ESRCH;
  	}
  	spin_lock_bh(&pmc->mca_lock);
  
  	sf_markstate(pmc);
  	isexclude = pmc->mca_sfmode == MCAST_EXCLUDE;
  	if (!delta)
  		pmc->mca_sfcount[sfmode]++;
  	err = 0;
  	for (i=0; i<sfcount; i++) {

  		err = ip6_mc_add1_src(pmc, sfmode, &psfsrc[i]);

  		if (err)
  			break;
  	}
  	if (err) {
  		int j;
  
  		if (!delta)
  			pmc->mca_sfcount[sfmode]--;
  		for (j=0; j<i; j++)
  			(void) ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
  	} else if (isexclude != (pmc->mca_sfcount[MCAST_EXCLUDE] != 0)) {

  		struct ip6_sf_list *psf;
  
  		/* filter mode change */
  		if (pmc->mca_sfcount[MCAST_EXCLUDE])
  			pmc->mca_sfmode = MCAST_EXCLUDE;
  		else if (pmc->mca_sfcount[MCAST_INCLUDE])
  			pmc->mca_sfmode = MCAST_INCLUDE;
  		/* else no filters; keep old mode for reports */
  
  		pmc->mca_crcount = idev->mc_qrv;
  		idev->mc_ifc_count = pmc->mca_crcount;
  		for (psf=pmc->mca_sources; psf; psf = psf->sf_next)
  			psf->sf_crcount = 0;
  		mld_ifc_event(idev);
  	} else if (sf_setstate(pmc))
  		mld_ifc_event(idev);
  	spin_unlock_bh(&pmc->mca_lock);
  	read_unlock_bh(&idev->lock);
  	return err;
  }
  
  static void ip6_mc_clear_src(struct ifmcaddr6 *pmc)
  {
  	struct ip6_sf_list *psf, *nextpsf;
  
  	for (psf=pmc->mca_tomb; psf; psf=nextpsf) {
  		nextpsf = psf->sf_next;
  		kfree(psf);
  	}
  	pmc->mca_tomb = NULL;
  	for (psf=pmc->mca_sources; psf; psf=nextpsf) {
  		nextpsf = psf->sf_next;
  		kfree(psf);
  	}
  	pmc->mca_sources = NULL;
  	pmc->mca_sfmode = MCAST_EXCLUDE;

  	pmc->mca_sfcount[MCAST_INCLUDE] = 0;

  	pmc->mca_sfcount[MCAST_EXCLUDE] = 1;
  }
  
  
  static void igmp6_join_group(struct ifmcaddr6 *ma)
  {
  	unsigned long delay;
  
  	if (ma->mca_flags & MAF_NOREPORT)
  		return;
  
  	igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
  
  	delay = net_random() % IGMP6_UNSOLICITED_IVAL;
  
  	spin_lock_bh(&ma->mca_lock);
  	if (del_timer(&ma->mca_timer)) {
  		atomic_dec(&ma->mca_refcnt);
  		delay = ma->mca_timer.expires - jiffies;
  	}
  
  	if (!mod_timer(&ma->mca_timer, jiffies + delay))
  		atomic_inc(&ma->mca_refcnt);
  	ma->mca_flags |= MAF_TIMER_RUNNING | MAF_LAST_REPORTER;
  	spin_unlock_bh(&ma->mca_lock);
  }
  
  static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
  			    struct inet6_dev *idev)
  {
  	int err;

  	/* callers have the socket lock and a write lock on ipv6_sk_mc_lock,
  	 * so no other readers or writers of iml or its sflist
  	 */

  	if (!iml->sflist) {

  		/* any-source empty exclude case */
  		return ip6_mc_del_src(idev, &iml->addr, iml->sfmode, 0, NULL, 0);
  	}
  	err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode,
  		iml->sflist->sl_count, iml->sflist->sl_addr, 0);
  	sock_kfree_s(sk, iml->sflist, IP6_SFLSIZE(iml->sflist->sl_max));
  	iml->sflist = NULL;
  	return err;
  }
  
  static void igmp6_leave_group(struct ifmcaddr6 *ma)
  {
  	if (MLD_V1_SEEN(ma->idev)) {
  		if (ma->mca_flags & MAF_LAST_REPORTER)
  			igmp6_send(&ma->mca_addr, ma->idev->dev,
  				ICMPV6_MGM_REDUCTION);
  	} else {
  		mld_add_delrec(ma->idev, ma);
  		mld_ifc_event(ma->idev);
  	}
  }
  
  static void mld_gq_timer_expire(unsigned long data)
  {
  	struct inet6_dev *idev = (struct inet6_dev *)data;
  
  	idev->mc_gq_running = 0;
  	mld_send_report(idev, NULL);
  	__in6_dev_put(idev);
  }
  
  static void mld_ifc_timer_expire(unsigned long data)
  {
  	struct inet6_dev *idev = (struct inet6_dev *)data;
  
  	mld_send_cr(idev);
  	if (idev->mc_ifc_count) {
  		idev->mc_ifc_count--;
  		if (idev->mc_ifc_count)
  			mld_ifc_start_timer(idev, idev->mc_maxdelay);
  	}
  	__in6_dev_put(idev);
  }
  
  static void mld_ifc_event(struct inet6_dev *idev)
  {
  	if (MLD_V1_SEEN(idev))
  		return;
  	idev->mc_ifc_count = idev->mc_qrv;
  	mld_ifc_start_timer(idev, 1);
  }
  
  
  static void igmp6_timer_handler(unsigned long data)
  {
  	struct ifmcaddr6 *ma = (struct ifmcaddr6 *) data;
  
  	if (MLD_V1_SEEN(ma->idev))
  		igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
  	else
  		mld_send_report(ma->idev, ma);
  
  	spin_lock(&ma->mca_lock);
  	ma->mca_flags |=  MAF_LAST_REPORTER;
  	ma->mca_flags &= ~MAF_TIMER_RUNNING;
  	spin_unlock(&ma->mca_lock);
  	ma_put(ma);
  }

  /* Device changing type */
  
  void ipv6_mc_unmap(struct inet6_dev *idev)
  {
  	struct ifmcaddr6 *i;
  
  	/* Install multicast list, except for all-nodes (already installed) */
  
  	read_lock_bh(&idev->lock);
  	for (i = idev->mc_list; i; i = i->next)
  		igmp6_group_dropped(i);
  	read_unlock_bh(&idev->lock);
  }
  
  void ipv6_mc_remap(struct inet6_dev *idev)
  {
  	ipv6_mc_up(idev);
  }

  /* Device going down */
  
  void ipv6_mc_down(struct inet6_dev *idev)
  {
  	struct ifmcaddr6 *i;
  
  	/* Withdraw multicast list */
  
  	read_lock_bh(&idev->lock);
  	idev->mc_ifc_count = 0;
  	if (del_timer(&idev->mc_ifc_timer))
  		__in6_dev_put(idev);
  	idev->mc_gq_running = 0;
  	if (del_timer(&idev->mc_gq_timer))
  		__in6_dev_put(idev);
  
  	for (i = idev->mc_list; i; i=i->next)
  		igmp6_group_dropped(i);
  	read_unlock_bh(&idev->lock);
  
  	mld_clear_delrec(idev);
  }
  
  
  /* Device going up */
  
  void ipv6_mc_up(struct inet6_dev *idev)
  {
  	struct ifmcaddr6 *i;
  
  	/* Install multicast list, except for all-nodes (already installed) */
  
  	read_lock_bh(&idev->lock);
  	for (i = idev->mc_list; i; i=i->next)
  		igmp6_group_added(i);
  	read_unlock_bh(&idev->lock);
  }
  
  /* IPv6 device initialization. */
  
  void ipv6_mc_init_dev(struct inet6_dev *idev)
  {

  	write_lock_bh(&idev->lock);

  	spin_lock_init(&idev->mc_lock);

  	idev->mc_gq_running = 0;

  	setup_timer(&idev->mc_gq_timer, mld_gq_timer_expire,
  			(unsigned long)idev);

  	idev->mc_tomb = NULL;
  	idev->mc_ifc_count = 0;

  	setup_timer(&idev->mc_ifc_timer, mld_ifc_timer_expire,
  			(unsigned long)idev);

  	idev->mc_qrv = MLD_QRV_DEFAULT;
  	idev->mc_maxdelay = IGMP6_UNSOLICITED_IVAL;
  	idev->mc_v1_seen = 0;
  	write_unlock_bh(&idev->lock);

  }
  
  /*
   *	Device is about to be destroyed: clean up.
   */
  
  void ipv6_mc_destroy_dev(struct inet6_dev *idev)
  {
  	struct ifmcaddr6 *i;

  
  	/* Deactivate timers */
  	ipv6_mc_down(idev);
  
  	/* Delete all-nodes address. */

  	/* We cannot call ipv6_dev_mc_dec() directly, our caller in
  	 * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will
  	 * fail.
  	 */

  	__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes);

  	if (idev->cnf.forwarding)
  		__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters);

  
  	write_lock_bh(&idev->lock);
  	while ((i = idev->mc_list) != NULL) {
  		idev->mc_list = i->next;
  		write_unlock_bh(&idev->lock);
  
  		igmp6_group_dropped(i);
  		ma_put(i);
  
  		write_lock_bh(&idev->lock);
  	}
  	write_unlock_bh(&idev->lock);
  }
  
  #ifdef CONFIG_PROC_FS
  struct igmp6_mc_iter_state {

  	struct seq_net_private p;

  	struct net_device *dev;
  	struct inet6_dev *idev;
  };
  
  #define igmp6_mc_seq_private(seq)	((struct igmp6_mc_iter_state *)(seq)->private)
  
  static inline struct ifmcaddr6 *igmp6_mc_get_first(struct seq_file *seq)
  {
  	struct ifmcaddr6 *im = NULL;
  	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);

  	struct net *net = seq_file_net(seq);

  	state->idev = NULL;

  	for_each_netdev_rcu(net, state->dev) {

  		struct inet6_dev *idev;

  		idev = __in6_dev_get(state->dev);

  		if (!idev)
  			continue;
  		read_lock_bh(&idev->lock);
  		im = idev->mc_list;
  		if (im) {
  			state->idev = idev;
  			break;
  		}
  		read_unlock_bh(&idev->lock);

  	}
  	return im;
  }
  
  static struct ifmcaddr6 *igmp6_mc_get_next(struct seq_file *seq, struct ifmcaddr6 *im)
  {
  	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
  
  	im = im->next;
  	while (!im) {

  		if (likely(state->idev != NULL))

  			read_unlock_bh(&state->idev->lock);

  
  		state->dev = next_net_device_rcu(state->dev);

  		if (!state->dev) {
  			state->idev = NULL;
  			break;
  		}

  		state->idev = __in6_dev_get(state->dev);

  		if (!state->idev)
  			continue;
  		read_lock_bh(&state->idev->lock);
  		im = state->idev->mc_list;
  	}
  	return im;
  }
  
  static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
  {
  	struct ifmcaddr6 *im = igmp6_mc_get_first(seq);
  	if (im)
  		while (pos && (im = igmp6_mc_get_next(seq, im)) != NULL)
  			--pos;
  	return pos ? NULL : im;
  }
  
  static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)

  	__acquires(RCU)

  {

  	rcu_read_lock();

  	return igmp6_mc_get_idx(seq, *pos);
  }
  
  static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
  {

  	struct ifmcaddr6 *im = igmp6_mc_get_next(seq, v);

  	++*pos;
  	return im;
  }
  
  static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)

  	__releases(RCU)

  {
  	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);

  	if (likely(state->idev != NULL)) {
  		read_unlock_bh(&state->idev->lock);

  		state->idev = NULL;
  	}
  	state->dev = NULL;

  	rcu_read_unlock();

  }
  
  static int igmp6_mc_seq_show(struct seq_file *seq, void *v)
  {
  	struct ifmcaddr6 *im = (struct ifmcaddr6 *)v;
  	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
  
  	seq_printf(seq,

  		   "%-4d %-15s %pi6 %5d %08X %ld
  ",

  		   state->dev->ifindex, state->dev->name,

  		   &im->mca_addr,

  		   im->mca_users, im->mca_flags,
  		   (im->mca_flags&MAF_TIMER_RUNNING) ?
  		   jiffies_to_clock_t(im->mca_timer.expires-jiffies) : 0);
  	return 0;
  }

  static const struct seq_operations igmp6_mc_seq_ops = {

  	.start	=	igmp6_mc_seq_start,
  	.next	=	igmp6_mc_seq_next,
  	.stop	=	igmp6_mc_seq_stop,
  	.show	=	igmp6_mc_seq_show,
  };
  
  static int igmp6_mc_seq_open(struct inode *inode, struct file *file)
  {

  	return seq_open_net(inode, file, &igmp6_mc_seq_ops,
  			    sizeof(struct igmp6_mc_iter_state));

  }

  static const struct file_operations igmp6_mc_seq_fops = {

  	.owner		=	THIS_MODULE,
  	.open		=	igmp6_mc_seq_open,
  	.read		=	seq_read,
  	.llseek		=	seq_lseek,

  	.release	=	seq_release_net,

  };
  
  struct igmp6_mcf_iter_state {

  	struct seq_net_private p;

  	struct net_device *dev;
  	struct inet6_dev *idev;
  	struct ifmcaddr6 *im;
  };
  
  #define igmp6_mcf_seq_private(seq)	((struct igmp6_mcf_iter_state *)(seq)->private)
  
  static inline struct ip6_sf_list *igmp6_mcf_get_first(struct seq_file *seq)
  {
  	struct ip6_sf_list *psf = NULL;
  	struct ifmcaddr6 *im = NULL;
  	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);

  	struct net *net = seq_file_net(seq);

  	state->idev = NULL;
  	state->im = NULL;

  	for_each_netdev_rcu(net, state->dev) {

  		struct inet6_dev *idev;

  		idev = __in6_dev_get(state->dev);

  		if (unlikely(idev == NULL))
  			continue;
  		read_lock_bh(&idev->lock);
  		im = idev->mc_list;
  		if (likely(im != NULL)) {
  			spin_lock_bh(&im->mca_lock);
  			psf = im->mca_sources;
  			if (likely(psf != NULL)) {
  				state->im = im;
  				state->idev = idev;
  				break;
  			}
  			spin_unlock_bh(&im->mca_lock);
  		}
  		read_unlock_bh(&idev->lock);

  	}
  	return psf;
  }
  
  static struct ip6_sf_list *igmp6_mcf_get_next(struct seq_file *seq, struct ip6_sf_list *psf)
  {
  	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
  
  	psf = psf->sf_next;
  	while (!psf) {
  		spin_unlock_bh(&state->im->mca_lock);
  		state->im = state->im->next;
  		while (!state->im) {

  			if (likely(state->idev != NULL))

  				read_unlock_bh(&state->idev->lock);

  
  			state->dev = next_net_device_rcu(state->dev);

  			if (!state->dev) {
  				state->idev = NULL;
  				goto out;
  			}

  			state->idev = __in6_dev_get(state->dev);

  			if (!state->idev)
  				continue;
  			read_lock_bh(&state->idev->lock);
  			state->im = state->idev->mc_list;
  		}
  		if (!state->im)
  			break;
  		spin_lock_bh(&state->im->mca_lock);
  		psf = state->im->mca_sources;
  	}
  out:
  	return psf;
  }
  
  static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
  {
  	struct ip6_sf_list *psf = igmp6_mcf_get_first(seq);
  	if (psf)
  		while (pos && (psf = igmp6_mcf_get_next(seq, psf)) != NULL)
  			--pos;
  	return pos ? NULL : psf;
  }
  
  static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)

  	__acquires(RCU)

  {

  	rcu_read_lock();

  	return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
  }
  
  static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
  {
  	struct ip6_sf_list *psf;
  	if (v == SEQ_START_TOKEN)
  		psf = igmp6_mcf_get_first(seq);
  	else
  		psf = igmp6_mcf_get_next(seq, v);
  	++*pos;
  	return psf;
  }
  
  static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)

  	__releases(RCU)

  {
  	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
  	if (likely(state->im != NULL)) {
  		spin_unlock_bh(&state->im->mca_lock);
  		state->im = NULL;
  	}
  	if (likely(state->idev != NULL)) {
  		read_unlock_bh(&state->idev->lock);

  		state->idev = NULL;
  	}
  	state->dev = NULL;

  	rcu_read_unlock();

  }
  
  static int igmp6_mcf_seq_show(struct seq_file *seq, void *v)
  {
  	struct ip6_sf_list *psf = (struct ip6_sf_list *)v;
  	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
  
  	if (v == SEQ_START_TOKEN) {

  		seq_printf(seq,

  			   "%3s %6s "

  			   "%32s %32s %6s %6s
  ", "Idx",

  			   "Device", "Multicast Address",
  			   "Source Address", "INC", "EXC");
  	} else {
  		seq_printf(seq,

  			   "%3d %6.6s %pi6 %pi6 %6lu %6lu
  ",

  			   state->dev->ifindex, state->dev->name,

  			   &state->im->mca_addr,
  			   &psf->sf_addr,

  			   psf->sf_count[MCAST_INCLUDE],
  			   psf->sf_count[MCAST_EXCLUDE]);
  	}
  	return 0;
  }

  static const struct seq_operations igmp6_mcf_seq_ops = {

  	.start	=	igmp6_mcf_seq_start,
  	.next	=	igmp6_mcf_seq_next,
  	.stop	=	igmp6_mcf_seq_stop,
  	.show	=	igmp6_mcf_seq_show,
  };
  
  static int igmp6_mcf_seq_open(struct inode *inode, struct file *file)
  {

  	return seq_open_net(inode, file, &igmp6_mcf_seq_ops,
  			    sizeof(struct igmp6_mcf_iter_state));

  }

  static const struct file_operations igmp6_mcf_seq_fops = {

  	.owner		=	THIS_MODULE,
  	.open		=	igmp6_mcf_seq_open,
  	.read		=	seq_read,
  	.llseek		=	seq_lseek,

  	.release	=	seq_release_net,

  };