/*
   * net/sched/act_api.c	Packet action API.
   *
   *		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.
   *
   * Author:	Jamal Hadi Salim
   *
   *
   */

  #include <linux/types.h>
  #include <linux/kernel.h>

  #include <linux/string.h>

  #include <linux/errno.h>

  #include <linux/slab.h>

  #include <linux/skbuff.h>

  #include <linux/init.h>
  #include <linux/kmod.h>

  #include <linux/err.h>

  #include <linux/module.h>

  #include <net/net_namespace.h>
  #include <net/sock.h>

  #include <net/sch_generic.h>
  #include <net/act_api.h>

  #include <net/netlink.h>

  void tcf_hash_destroy(struct tcf_common *p, struct tcf_hashinfo *hinfo)
  {
  	unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
  	struct tcf_common **p1p;
  
  	for (p1p = &hinfo->htab[h]; *p1p; p1p = &(*p1p)->tcfc_next) {
  		if (*p1p == p) {
  			write_lock_bh(hinfo->lock);
  			*p1p = p->tcfc_next;
  			write_unlock_bh(hinfo->lock);

  			gen_kill_estimator(&p->tcfc_bstats,
  					   &p->tcfc_rate_est);

  			/*
  			 * gen_estimator est_timer() might access p->tcfc_lock
  			 * or bstats, wait a RCU grace period before freeing p
  			 */

  			kfree_rcu(p, tcfc_rcu);

  			return;
  		}
  	}

  	WARN_ON(1);

  }
  EXPORT_SYMBOL(tcf_hash_destroy);
  
  int tcf_hash_release(struct tcf_common *p, int bind,
  		     struct tcf_hashinfo *hinfo)
  {
  	int ret = 0;
  
  	if (p) {
  		if (bind)
  			p->tcfc_bindcnt--;
  
  		p->tcfc_refcnt--;

  		if (p->tcfc_bindcnt <= 0 && p->tcfc_refcnt <= 0) {

  			tcf_hash_destroy(p, hinfo);
  			ret = 1;
  		}
  	}
  	return ret;
  }
  EXPORT_SYMBOL(tcf_hash_release);
  
  static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
  			   struct tc_action *a, struct tcf_hashinfo *hinfo)
  {
  	struct tcf_common *p;

  	int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;

  	struct nlattr *nest;

  	read_lock_bh(hinfo->lock);

  
  	s_i = cb->args[0];
  
  	for (i = 0; i < (hinfo->hmask + 1); i++) {
  		p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
  
  		for (; p; p = p->tcfc_next) {
  			index++;
  			if (index < s_i)
  				continue;
  			a->priv = p;
  			a->order = n_i;

  
  			nest = nla_nest_start(skb, a->order);
  			if (nest == NULL)
  				goto nla_put_failure;

  			err = tcf_action_dump_1(skb, a, 0, 0);
  			if (err < 0) {
  				index--;

  				nlmsg_trim(skb, nest);

  				goto done;
  			}

  			nla_nest_end(skb, nest);

  			n_i++;
  			if (n_i >= TCA_ACT_MAX_PRIO)
  				goto done;
  		}
  	}
  done:

  	read_unlock_bh(hinfo->lock);

  	if (n_i)
  		cb->args[0] += n_i;
  	return n_i;

  nla_put_failure:

  	nla_nest_cancel(skb, nest);

  	goto done;
  }
  
  static int tcf_del_walker(struct sk_buff *skb, struct tc_action *a,
  			  struct tcf_hashinfo *hinfo)
  {
  	struct tcf_common *p, *s_p;

  	struct nlattr *nest;

  	int i = 0, n_i = 0;

  	nest = nla_nest_start(skb, a->order);
  	if (nest == NULL)
  		goto nla_put_failure;

  	NLA_PUT_STRING(skb, TCA_KIND, a->ops->kind);

  	for (i = 0; i < (hinfo->hmask + 1); i++) {
  		p = hinfo->htab[tcf_hash(i, hinfo->hmask)];
  
  		while (p != NULL) {
  			s_p = p->tcfc_next;
  			if (ACT_P_DELETED == tcf_hash_release(p, 0, hinfo))

  				module_put(a->ops->owner);

  			n_i++;
  			p = s_p;
  		}
  	}

  	NLA_PUT_U32(skb, TCA_FCNT, n_i);

  	nla_nest_end(skb, nest);

  
  	return n_i;

  nla_put_failure:

  	nla_nest_cancel(skb, nest);

  	return -EINVAL;
  }
  
  int tcf_generic_walker(struct sk_buff *skb, struct netlink_callback *cb,
  		       int type, struct tc_action *a)
  {
  	struct tcf_hashinfo *hinfo = a->ops->hinfo;
  
  	if (type == RTM_DELACTION) {
  		return tcf_del_walker(skb, a, hinfo);
  	} else if (type == RTM_GETACTION) {
  		return tcf_dump_walker(skb, cb, a, hinfo);
  	} else {

  		WARN(1, "tcf_generic_walker: unknown action %d
  ", type);

  		return -EINVAL;
  	}
  }
  EXPORT_SYMBOL(tcf_generic_walker);
  
  struct tcf_common *tcf_hash_lookup(u32 index, struct tcf_hashinfo *hinfo)
  {
  	struct tcf_common *p;

  	read_lock_bh(hinfo->lock);

  	for (p = hinfo->htab[tcf_hash(index, hinfo->hmask)]; p;
  	     p = p->tcfc_next) {
  		if (p->tcfc_index == index)
  			break;
  	}

  	read_unlock_bh(hinfo->lock);

  
  	return p;
  }
  EXPORT_SYMBOL(tcf_hash_lookup);
  
  u32 tcf_hash_new_index(u32 *idx_gen, struct tcf_hashinfo *hinfo)
  {
  	u32 val = *idx_gen;
  
  	do {
  		if (++val == 0)
  			val = 1;
  	} while (tcf_hash_lookup(val, hinfo));
  
  	return (*idx_gen = val);
  }
  EXPORT_SYMBOL(tcf_hash_new_index);
  
  int tcf_hash_search(struct tc_action *a, u32 index)
  {
  	struct tcf_hashinfo *hinfo = a->ops->hinfo;
  	struct tcf_common *p = tcf_hash_lookup(index, hinfo);
  
  	if (p) {
  		a->priv = p;
  		return 1;
  	}
  	return 0;
  }
  EXPORT_SYMBOL(tcf_hash_search);
  
  struct tcf_common *tcf_hash_check(u32 index, struct tc_action *a, int bind,
  				  struct tcf_hashinfo *hinfo)
  {
  	struct tcf_common *p = NULL;
  	if (index && (p = tcf_hash_lookup(index, hinfo)) != NULL) {

  		if (bind)

  			p->tcfc_bindcnt++;

  		p->tcfc_refcnt++;

  		a->priv = p;
  	}
  	return p;
  }
  EXPORT_SYMBOL(tcf_hash_check);

  struct tcf_common *tcf_hash_create(u32 index, struct nlattr *est,
  				   struct tc_action *a, int size, int bind,
  				   u32 *idx_gen, struct tcf_hashinfo *hinfo)

  {
  	struct tcf_common *p = kzalloc(size, GFP_KERNEL);
  
  	if (unlikely(!p))

  		return ERR_PTR(-ENOMEM);

  	p->tcfc_refcnt = 1;
  	if (bind)
  		p->tcfc_bindcnt = 1;
  
  	spin_lock_init(&p->tcfc_lock);

  	p->tcfc_index = index ? index : tcf_hash_new_index(idx_gen, hinfo);
  	p->tcfc_tm.install = jiffies;
  	p->tcfc_tm.lastuse = jiffies;

  	if (est) {
  		int err = gen_new_estimator(&p->tcfc_bstats, &p->tcfc_rate_est,
  					    &p->tcfc_lock, est);
  		if (err) {
  			kfree(p);
  			return ERR_PTR(err);
  		}
  	}

  	a->priv = (void *) p;
  	return p;
  }
  EXPORT_SYMBOL(tcf_hash_create);
  
  void tcf_hash_insert(struct tcf_common *p, struct tcf_hashinfo *hinfo)
  {
  	unsigned int h = tcf_hash(p->tcfc_index, hinfo->hmask);
  
  	write_lock_bh(hinfo->lock);
  	p->tcfc_next = hinfo->htab[h];
  	hinfo->htab[h] = p;
  	write_unlock_bh(hinfo->lock);
  }
  EXPORT_SYMBOL(tcf_hash_insert);

  
  static struct tc_action_ops *act_base = NULL;
  static DEFINE_RWLOCK(act_mod_lock);
  
  int tcf_register_action(struct tc_action_ops *act)
  {
  	struct tc_action_ops *a, **ap;
  
  	write_lock(&act_mod_lock);
  	for (ap = &act_base; (a = *ap) != NULL; ap = &a->next) {
  		if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
  			write_unlock(&act_mod_lock);
  			return -EEXIST;
  		}
  	}
  	act->next = NULL;
  	*ap = act;
  	write_unlock(&act_mod_lock);
  	return 0;
  }

  EXPORT_SYMBOL(tcf_register_action);

  
  int tcf_unregister_action(struct tc_action_ops *act)
  {
  	struct tc_action_ops *a, **ap;
  	int err = -ENOENT;
  
  	write_lock(&act_mod_lock);
  	for (ap = &act_base; (a = *ap) != NULL; ap = &a->next)
  		if (a == act)
  			break;
  	if (a) {
  		*ap = a->next;
  		a->next = NULL;
  		err = 0;
  	}
  	write_unlock(&act_mod_lock);
  	return err;
  }

  EXPORT_SYMBOL(tcf_unregister_action);

  
  /* lookup by name */
  static struct tc_action_ops *tc_lookup_action_n(char *kind)
  {
  	struct tc_action_ops *a = NULL;
  
  	if (kind) {
  		read_lock(&act_mod_lock);
  		for (a = act_base; a; a = a->next) {
  			if (strcmp(kind, a->kind) == 0) {
  				if (!try_module_get(a->owner)) {
  					read_unlock(&act_mod_lock);
  					return NULL;
  				}
  				break;
  			}
  		}
  		read_unlock(&act_mod_lock);
  	}
  	return a;
  }

  /* lookup by nlattr */
  static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)

  {
  	struct tc_action_ops *a = NULL;
  
  	if (kind) {
  		read_lock(&act_mod_lock);
  		for (a = act_base; a; a = a->next) {

  			if (nla_strcmp(kind, a->kind) == 0) {

  				if (!try_module_get(a->owner)) {
  					read_unlock(&act_mod_lock);
  					return NULL;
  				}
  				break;
  			}
  		}
  		read_unlock(&act_mod_lock);
  	}
  	return a;
  }
  
  #if 0
  /* lookup by id */
  static struct tc_action_ops *tc_lookup_action_id(u32 type)
  {
  	struct tc_action_ops *a = NULL;
  
  	if (type) {
  		read_lock(&act_mod_lock);
  		for (a = act_base; a; a = a->next) {
  			if (a->type == type) {
  				if (!try_module_get(a->owner)) {
  					read_unlock(&act_mod_lock);
  					return NULL;
  				}
  				break;
  			}
  		}
  		read_unlock(&act_mod_lock);
  	}
  	return a;
  }
  #endif

  int tcf_action_exec(struct sk_buff *skb, const struct tc_action *act,

  		    struct tcf_result *res)

  {

  	const struct tc_action *a;

  	int ret = -1;
  
  	if (skb->tc_verd & TC_NCLS) {
  		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);

  		ret = TC_ACT_OK;
  		goto exec_done;
  	}
  	while ((a = act) != NULL) {
  repeat:
  		if (a->ops && a->ops->act) {

  			ret = a->ops->act(skb, a, res);

  			if (TC_MUNGED & skb->tc_verd) {
  				/* copied already, allow trampling */
  				skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
  				skb->tc_verd = CLR_TC_MUNGED(skb->tc_verd);
  			}

  			if (ret == TC_ACT_REPEAT)
  				goto repeat;	/* we need a ttl - JHS */

  			if (ret != TC_ACT_PIPE)
  				goto exec_done;

  		}
  		act = a->next;
  	}
  exec_done:

  	return ret;
  }

  EXPORT_SYMBOL(tcf_action_exec);

  
  void tcf_action_destroy(struct tc_action *act, int bind)
  {
  	struct tc_action *a;
  
  	for (a = act; a; a = act) {
  		if (a->ops && a->ops->cleanup) {

  			if (a->ops->cleanup(a, bind) == ACT_P_DELETED)
  				module_put(a->ops->owner);
  			act = act->next;
  			kfree(a);

  		} else {
  			/*FIXME: Remove later - catch insertion bugs*/
  			WARN(1, "tcf_action_destroy: BUG? destroying NULL ops
  ");

  			act = act->next;
  			kfree(a);
  		}
  	}
  }
  
  int
  tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
  {
  	int err = -EINVAL;
  
  	if (a->ops == NULL || a->ops->dump == NULL)
  		return err;
  	return a->ops->dump(skb, a, bind, ref);
  }
  
  int
  tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
  {
  	int err = -EINVAL;

  	unsigned char *b = skb_tail_pointer(skb);

  	struct nlattr *nest;

  
  	if (a->ops == NULL || a->ops->dump == NULL)
  		return err;

  	NLA_PUT_STRING(skb, TCA_KIND, a->ops->kind);

  	if (tcf_action_copy_stats(skb, a, 0))

  		goto nla_put_failure;

  	nest = nla_nest_start(skb, TCA_OPTIONS);
  	if (nest == NULL)
  		goto nla_put_failure;

  	err = tcf_action_dump_old(skb, a, bind, ref);
  	if (err > 0) {

  		nla_nest_end(skb, nest);

  		return err;
  	}

  nla_put_failure:

  	nlmsg_trim(skb, b);

  	return -1;
  }

  EXPORT_SYMBOL(tcf_action_dump_1);

  
  int
  tcf_action_dump(struct sk_buff *skb, struct tc_action *act, int bind, int ref)
  {
  	struct tc_action *a;
  	int err = -EINVAL;

  	struct nlattr *nest;

  
  	while ((a = act) != NULL) {

  		act = a->next;

  		nest = nla_nest_start(skb, a->order);
  		if (nest == NULL)
  			goto nla_put_failure;

  		err = tcf_action_dump_1(skb, a, bind, ref);
  		if (err < 0)

  			goto errout;

  		nla_nest_end(skb, nest);

  	}
  
  	return 0;

  nla_put_failure:

  	err = -EINVAL;
  errout:

  	nla_nest_cancel(skb, nest);

  	return err;

  }

  struct tc_action *tcf_action_init_1(struct nlattr *nla, struct nlattr *est,

  				    char *name, int ovr, int bind)

  {
  	struct tc_action *a;
  	struct tc_action_ops *a_o;
  	char act_name[IFNAMSIZ];

  	struct nlattr *tb[TCA_ACT_MAX + 1];

  	struct nlattr *kind;

  	int err;

  	if (name == NULL) {

  		err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
  		if (err < 0)

  			goto err_out;

  		err = -EINVAL;

  		kind = tb[TCA_ACT_KIND];

  		if (kind == NULL)
  			goto err_out;

  		if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)

  			goto err_out;
  	} else {

  		err = -EINVAL;

  		if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
  			goto err_out;
  	}
  
  	a_o = tc_lookup_action_n(act_name);
  	if (a_o == NULL) {

  #ifdef CONFIG_MODULES

  		rtnl_unlock();

  		request_module("act_%s", act_name);

  		rtnl_lock();
  
  		a_o = tc_lookup_action_n(act_name);
  
  		/* We dropped the RTNL semaphore in order to
  		 * perform the module load.  So, even if we
  		 * succeeded in loading the module we have to
  		 * tell the caller to replay the request.  We
  		 * indicate this using -EAGAIN.
  		 */
  		if (a_o != NULL) {

  			err = -EAGAIN;

  			goto err_mod;
  		}
  #endif

  		err = -ENOENT;

  		goto err_out;
  	}

  	err = -ENOMEM;

  	a = kzalloc(sizeof(*a), GFP_KERNEL);

  	if (a == NULL)
  		goto err_mod;

  
  	/* backward compatibility for policer */
  	if (name == NULL)

  		err = a_o->init(tb[TCA_ACT_OPTIONS], est, a, ovr, bind);

  	else

  		err = a_o->init(nla, est, a, ovr, bind);
  	if (err < 0)

  		goto err_free;
  
  	/* module count goes up only when brand new policy is created

  	 * if it exists and is only bound to in a_o->init() then
  	 * ACT_P_CREATED is not returned (a zero is).
  	 */

  	if (err != ACT_P_CREATED)

  		module_put(a_o->owner);
  	a->ops = a_o;

  	return a;
  
  err_free:
  	kfree(a);
  err_mod:
  	module_put(a_o->owner);
  err_out:

  	return ERR_PTR(err);

  }

  struct tc_action *tcf_action_init(struct nlattr *nla, struct nlattr *est,

  				  char *name, int ovr, int bind)

  {

  	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];

  	struct tc_action *head = NULL, *act, *act_prev = NULL;

  	int err;

  	int i;

  	err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
  	if (err < 0)
  		return ERR_PTR(err);

  	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {

  		act = tcf_action_init_1(tb[i], est, name, ovr, bind);
  		if (IS_ERR(act))

  			goto err;

  		act->order = i;

  
  		if (head == NULL)
  			head = act;
  		else
  			act_prev->next = act;
  		act_prev = act;
  	}
  	return head;
  
  err:
  	if (head != NULL)
  		tcf_action_destroy(head, bind);

  	return act;

  }
  
  int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
  			  int compat_mode)
  {
  	int err = 0;
  	struct gnet_dump d;
  	struct tcf_act_hdr *h = a->priv;

  	if (h == NULL)
  		goto errout;
  
  	/* compat_mode being true specifies a call that is supposed

  	 * to add additional backward compatibility statistic TLVs.

  	 */
  	if (compat_mode) {
  		if (a->type == TCA_OLD_COMPAT)
  			err = gnet_stats_start_copy_compat(skb, 0,

  				TCA_STATS, TCA_XSTATS, &h->tcf_lock, &d);

  		else
  			return 0;
  	} else
  		err = gnet_stats_start_copy(skb, TCA_ACT_STATS,

  					    &h->tcf_lock, &d);

  
  	if (err < 0)
  		goto errout;
  
  	if (a->ops != NULL && a->ops->get_stats != NULL)
  		if (a->ops->get_stats(skb, a) < 0)
  			goto errout;

  	if (gnet_stats_copy_basic(&d, &h->tcf_bstats) < 0 ||

  	    gnet_stats_copy_rate_est(&d, &h->tcf_bstats,
  				     &h->tcf_rate_est) < 0 ||

  	    gnet_stats_copy_queue(&d, &h->tcf_qstats) < 0)

  		goto errout;
  
  	if (gnet_stats_finish_copy(&d) < 0)
  		goto errout;
  
  	return 0;
  
  errout:
  	return -1;
  }
  
  static int
  tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 pid, u32 seq,

  	     u16 flags, int event, int bind, int ref)

  {
  	struct tcamsg *t;
  	struct nlmsghdr *nlh;

  	unsigned char *b = skb_tail_pointer(skb);

  	struct nlattr *nest;

  	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);

  	t = NLMSG_DATA(nlh);
  	t->tca_family = AF_UNSPEC;

  	t->tca__pad1 = 0;
  	t->tca__pad2 = 0;

  	nest = nla_nest_start(skb, TCA_ACT_TAB);
  	if (nest == NULL)
  		goto nla_put_failure;

  
  	if (tcf_action_dump(skb, a, bind, ref) < 0)

  		goto nla_put_failure;

  	nla_nest_end(skb, nest);

  	nlh->nlmsg_len = skb_tail_pointer(skb) - b;

  	return skb->len;

  nla_put_failure:

  nlmsg_failure:

  	nlmsg_trim(skb, b);

  	return -1;
  }
  
  static int

  act_get_notify(struct net *net, u32 pid, struct nlmsghdr *n,
  	       struct tc_action *a, int event)

  {
  	struct sk_buff *skb;

  
  	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
  	if (!skb)
  		return -ENOBUFS;
  	if (tca_get_fill(skb, a, pid, n->nlmsg_seq, 0, event, 0, 0) <= 0) {
  		kfree_skb(skb);
  		return -EINVAL;
  	}

  	return rtnl_unicast(skb, net, pid);

  }
  
  static struct tc_action *

  tcf_action_get_1(struct nlattr *nla, struct nlmsghdr *n, u32 pid)

  {

  	struct nlattr *tb[TCA_ACT_MAX + 1];

  	struct tc_action *a;
  	int index;

  	int err;

  	err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
  	if (err < 0)

  		goto err_out;

  	err = -EINVAL;

  	if (tb[TCA_ACT_INDEX] == NULL ||
  	    nla_len(tb[TCA_ACT_INDEX]) < sizeof(index))

  		goto err_out;

  	index = nla_get_u32(tb[TCA_ACT_INDEX]);

  	err = -ENOMEM;

  	a = kzalloc(sizeof(struct tc_action), GFP_KERNEL);

  	if (a == NULL)

  		goto err_out;

  	err = -EINVAL;

  	a->ops = tc_lookup_action(tb[TCA_ACT_KIND]);

  	if (a->ops == NULL)
  		goto err_free;
  	if (a->ops->lookup == NULL)
  		goto err_mod;

  	err = -ENOENT;

  	if (a->ops->lookup(a, index) == 0)
  		goto err_mod;
  
  	module_put(a->ops->owner);

  	return a;

  err_mod:
  	module_put(a->ops->owner);
  err_free:
  	kfree(a);

  err_out:
  	return ERR_PTR(err);

  }
  
  static void cleanup_a(struct tc_action *act)
  {
  	struct tc_action *a;
  
  	for (a = act; a; a = act) {
  		act = a->next;
  		kfree(a);
  	}
  }
  
  static struct tc_action *create_a(int i)
  {
  	struct tc_action *act;

  	act = kzalloc(sizeof(*act), GFP_KERNEL);

  	if (act == NULL) {

  		pr_debug("create_a: failed to alloc!
  ");

  		return NULL;
  	}

  	act->order = i;
  	return act;
  }

  static int tca_action_flush(struct net *net, struct nlattr *nla,
  			    struct nlmsghdr *n, u32 pid)

  {
  	struct sk_buff *skb;
  	unsigned char *b;
  	struct nlmsghdr *nlh;
  	struct tcamsg *t;
  	struct netlink_callback dcb;

  	struct nlattr *nest;

  	struct nlattr *tb[TCA_ACT_MAX + 1];

  	struct nlattr *kind;

  	struct tc_action *a = create_a(0);

  	int err = -ENOMEM;

  
  	if (a == NULL) {

  		pr_debug("tca_action_flush: couldnt create tc_action
  ");

  		return err;
  	}
  
  	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
  	if (!skb) {

  		pr_debug("tca_action_flush: failed skb alloc
  ");

  		kfree(a);

  		return err;

  	}

  	b = skb_tail_pointer(skb);

  	err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL);
  	if (err < 0)

  		goto err_out;

  	err = -EINVAL;

  	kind = tb[TCA_ACT_KIND];

  	a->ops = tc_lookup_action(kind);
  	if (a->ops == NULL)
  		goto err_out;
  
  	nlh = NLMSG_PUT(skb, pid, n->nlmsg_seq, RTM_DELACTION, sizeof(*t));
  	t = NLMSG_DATA(nlh);
  	t->tca_family = AF_UNSPEC;

  	t->tca__pad1 = 0;
  	t->tca__pad2 = 0;

  	nest = nla_nest_start(skb, TCA_ACT_TAB);
  	if (nest == NULL)
  		goto nla_put_failure;

  
  	err = a->ops->walk(skb, &dcb, RTM_DELACTION, a);
  	if (err < 0)

  		goto nla_put_failure;

  	if (err == 0)
  		goto noflush_out;

  	nla_nest_end(skb, nest);

  	nlh->nlmsg_len = skb_tail_pointer(skb) - b;

  	nlh->nlmsg_flags |= NLM_F_ROOT;
  	module_put(a->ops->owner);
  	kfree(a);

  	err = rtnetlink_send(skb, net, pid, RTNLGRP_TC,
  			     n->nlmsg_flags & NLM_F_ECHO);

  	if (err > 0)
  		return 0;
  
  	return err;

  nla_put_failure:

  nlmsg_failure:

  	module_put(a->ops->owner);

  err_out:

  noflush_out:

  	kfree_skb(skb);
  	kfree(a);
  	return err;
  }
  
  static int

  tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
  	      u32 pid, int event)

  {

  	int i, ret;

  	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];

  	struct tc_action *head = NULL, *act, *act_prev = NULL;

  	ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
  	if (ret < 0)
  		return ret;

  	if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {

  		if (tb[1] != NULL)

  			return tca_action_flush(net, tb[1], n, pid);

  		else
  			return -EINVAL;

  	}

  	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {

  		act = tcf_action_get_1(tb[i], n, pid);
  		if (IS_ERR(act)) {
  			ret = PTR_ERR(act);

  			goto err;

  		}

  		act->order = i;

  
  		if (head == NULL)
  			head = act;
  		else
  			act_prev->next = act;
  		act_prev = act;
  	}
  
  	if (event == RTM_GETACTION)

  		ret = act_get_notify(net, pid, n, head, event);

  	else { /* delete */
  		struct sk_buff *skb;
  
  		skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
  		if (!skb) {
  			ret = -ENOBUFS;
  			goto err;
  		}
  
  		if (tca_get_fill(skb, head, pid, n->nlmsg_seq, 0, event,

  				 0, 1) <= 0) {

  			kfree_skb(skb);
  			ret = -EINVAL;
  			goto err;
  		}
  
  		/* now do the delete */
  		tcf_action_destroy(head, 0);

  		ret = rtnetlink_send(skb, net, pid, RTNLGRP_TC,

  				     n->nlmsg_flags & NLM_F_ECHO);

  		if (ret > 0)
  			return 0;
  		return ret;
  	}
  err:
  	cleanup_a(head);
  	return ret;
  }

  static int tcf_add_notify(struct net *net, struct tc_action *a,
  			  u32 pid, u32 seq, int event, u16 flags)

  {
  	struct tcamsg *t;
  	struct nlmsghdr *nlh;
  	struct sk_buff *skb;

  	struct nlattr *nest;

  	unsigned char *b;
  	int err = 0;
  
  	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
  	if (!skb)
  		return -ENOBUFS;

  	b = skb_tail_pointer(skb);

  	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);

  	t = NLMSG_DATA(nlh);
  	t->tca_family = AF_UNSPEC;

  	t->tca__pad1 = 0;
  	t->tca__pad2 = 0;

  	nest = nla_nest_start(skb, TCA_ACT_TAB);
  	if (nest == NULL)
  		goto nla_put_failure;

  
  	if (tcf_action_dump(skb, a, 0, 0) < 0)

  		goto nla_put_failure;

  	nla_nest_end(skb, nest);

  	nlh->nlmsg_len = skb_tail_pointer(skb) - b;

  	NETLINK_CB(skb).dst_group = RTNLGRP_TC;

  	err = rtnetlink_send(skb, net, pid, RTNLGRP_TC, flags & NLM_F_ECHO);

  	if (err > 0)
  		err = 0;
  	return err;

  nla_put_failure:

  nlmsg_failure:

  	kfree_skb(skb);

  	return -1;
  }

  static int

  tcf_action_add(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
  	       u32 pid, int ovr)

  {
  	int ret = 0;
  	struct tc_action *act;
  	struct tc_action *a;
  	u32 seq = n->nlmsg_seq;

  	act = tcf_action_init(nla, NULL, NULL, ovr, 0);

  	if (act == NULL)
  		goto done;

  	if (IS_ERR(act)) {
  		ret = PTR_ERR(act);
  		goto done;
  	}

  
  	/* dump then free all the actions after update; inserted policy
  	 * stays intact

  	 */

  	ret = tcf_add_notify(net, act, pid, seq, RTM_NEWACTION, n->nlmsg_flags);

  	for (a = act; a; a = act) {
  		act = a->next;
  		kfree(a);
  	}
  done:
  	return ret;
  }
  
  static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
  {

  	struct net *net = sock_net(skb->sk);

  	struct nlattr *tca[TCA_ACT_MAX + 1];

  	u32 pid = skb ? NETLINK_CB(skb).pid : 0;
  	int ret = 0, ovr = 0;

  	ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ACT_MAX, NULL);
  	if (ret < 0)
  		return ret;
  
  	if (tca[TCA_ACT_TAB] == NULL) {

  		pr_notice("tc_ctl_action: received NO action attribs
  ");

  		return -EINVAL;
  	}

  	/* n->nlmsg_flags & NLM_F_CREATE */

  	switch (n->nlmsg_type) {
  	case RTM_NEWACTION:
  		/* we are going to assume all other flags

  		 * imply create only if it doesn't exist

  		 * Note that CREATE | EXCL implies that
  		 * but since we want avoid ambiguity (eg when flags
  		 * is zero) then just set this
  		 */

  		if (n->nlmsg_flags & NLM_F_REPLACE)

  			ovr = 1;
  replay:

  		ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, pid, ovr);

  		if (ret == -EAGAIN)
  			goto replay;
  		break;
  	case RTM_DELACTION:

  		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
  				    pid, RTM_DELACTION);

  		break;
  	case RTM_GETACTION:

  		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
  				    pid, RTM_GETACTION);

  		break;
  	default:
  		BUG();
  	}
  
  	return ret;
  }

  static struct nlattr *

  find_dump_kind(const struct nlmsghdr *n)

  {

  	struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];

  	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
  	struct nlattr *nla[TCAA_MAX + 1];
  	struct nlattr *kind;

  	if (nlmsg_parse(n, sizeof(struct tcamsg), nla, TCAA_MAX, NULL) < 0)

  		return NULL;

  	tb1 = nla[TCA_ACT_TAB];

  	if (tb1 == NULL)
  		return NULL;

  	if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
  		      NLMSG_ALIGN(nla_len(tb1)), NULL) < 0)

  		return NULL;

  	if (tb[1] == NULL)
  		return NULL;
  	if (nla_parse(tb2, TCA_ACT_MAX, nla_data(tb[1]),
  		      nla_len(tb[1]), NULL) < 0)

  		return NULL;

  	kind = tb2[TCA_ACT_KIND];

  	return kind;

  }
  
  static int
  tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
  {
  	struct nlmsghdr *nlh;

  	unsigned char *b = skb_tail_pointer(skb);

  	struct nlattr *nest;

  	struct tc_action_ops *a_o;
  	struct tc_action a;
  	int ret = 0;
  	struct tcamsg *t = (struct tcamsg *) NLMSG_DATA(cb->nlh);

  	struct nlattr *kind = find_dump_kind(cb->nlh);

  
  	if (kind == NULL) {

  		pr_info("tc_dump_action: action bad kind
  ");

  		return 0;
  	}

  	a_o = tc_lookup_action(kind);

  	if (a_o == NULL)

  		return 0;

  
  	memset(&a, 0, sizeof(struct tc_action));
  	a.ops = a_o;
  
  	if (a_o->walk == NULL) {

  		WARN(1, "tc_dump_action: %s !capable of dumping table
  ",
  		     a_o->kind);

  		goto nla_put_failure;

  	}
  
  	nlh = NLMSG_PUT(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,

  			cb->nlh->nlmsg_type, sizeof(*t));

  	t = NLMSG_DATA(nlh);
  	t->tca_family = AF_UNSPEC;

  	t->tca__pad1 = 0;
  	t->tca__pad2 = 0;

  	nest = nla_nest_start(skb, TCA_ACT_TAB);
  	if (nest == NULL)
  		goto nla_put_failure;

  
  	ret = a_o->walk(skb, cb, RTM_GETACTION, &a);
  	if (ret < 0)

  		goto nla_put_failure;

  
  	if (ret > 0) {

  		nla_nest_end(skb, nest);

  		ret = skb->len;
  	} else

  		nla_nest_cancel(skb, nest);

  	nlh->nlmsg_len = skb_tail_pointer(skb) - b;

  	if (NETLINK_CB(cb->skb).pid && ret)
  		nlh->nlmsg_flags |= NLM_F_MULTI;
  	module_put(a_o->owner);
  	return skb->len;

  nla_put_failure:

  nlmsg_failure:
  	module_put(a_o->owner);

  	nlmsg_trim(skb, b);

  	return skb->len;
  }
  
  static int __init tc_action_init(void)
  {

  	rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, NULL);
  	rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, NULL);
  	rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
  		      NULL);

  	return 0;
  }
  
  subsys_initcall(tc_action_init);