Commit e89fc3f1 authored by Alexey Dobriyan's avatar Alexey Dobriyan Committed by Patrick McHardy
Browse files

netfilter: xt_hashlimit: netns support 



Make hashtable per-netns.
Make proc files per-netns.

Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
parent 7d07d563

net/netfilter/xt_hashlimit.c

+98 −43
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ 
#endif



#include <net/net_namespace.h>

#include <net/netns/generic.h>



#include <linux/netfilter/x_tables.h>

#include <linux/netfilter_ipv4/ip_tables.h>
@@ -40,9 +41,19 @@ MODULE_DESCRIPTION("Xtables: per hash-bucket rate-limit match"); 
MODULE_ALIAS("ipt_hashlimit");

MODULE_ALIAS("ip6t_hashlimit");



struct hashlimit_net {

	struct hlist_head	htables;

	struct proc_dir_entry	*ipt_hashlimit;

	struct proc_dir_entry	*ip6t_hashlimit;

};



static int hashlimit_net_id;

static inline struct hashlimit_net *hashlimit_pernet(struct net *net)

{

	return net_generic(net, hashlimit_net_id);

}



/* need to declare this at the top */

static struct proc_dir_entry *hashlimit_procdir4;

static struct proc_dir_entry *hashlimit_procdir6;

static const struct file_operations dl_file_ops;



/* hash table crap */
@@ -93,13 +104,13 @@ struct xt_hashlimit_htable { 


	/* seq_file stuff */

	struct proc_dir_entry *pde;

	struct net *net;



	struct hlist_head hash[0];	/* hashtable itself */

};



static DEFINE_SPINLOCK(hashlimit_lock);	/* protects htables list */

static DEFINE_MUTEX(hlimit_mutex);	/* additional checkentry protection */

static HLIST_HEAD(hashlimit_htables);

static struct kmem_cache *hashlimit_cachep __read_mostly;



static inline bool dst_cmp(const struct dsthash_ent *ent,
@@ -185,8 +196,9 @@ dsthash_free(struct xt_hashlimit_htable *ht, struct dsthash_ent *ent) 
}

static void htable_gc(unsigned long htlong);



static int htable_create_v0(struct xt_hashlimit_info *minfo, u_int8_t family)

static int htable_create_v0(struct net *net, struct xt_hashlimit_info *minfo, u_int8_t family)

{

	struct hashlimit_net *hashlimit_net = hashlimit_pernet(net);

	struct xt_hashlimit_htable *hinfo;

	unsigned int size;

	unsigned int i;
@@ -239,26 +251,29 @@ static int htable_create_v0(struct xt_hashlimit_info *minfo, u_int8_t family) 
	spin_lock_init(&hinfo->lock);

	hinfo->pde = proc_create_data(minfo->name, 0,

		(family == NFPROTO_IPV4) ?

		hashlimit_procdir4 : hashlimit_procdir6,

		hashlimit_net->ipt_hashlimit : hashlimit_net->ip6t_hashlimit,

		&dl_file_ops, hinfo);

	if (!hinfo->pde) {

		vfree(hinfo);

		return -1;

	}

	hinfo->net = net;



	setup_timer(&hinfo->timer, htable_gc, (unsigned long )hinfo);

	hinfo->timer.expires = jiffies + msecs_to_jiffies(hinfo->cfg.gc_interval);

	add_timer(&hinfo->timer);



	spin_lock_bh(&hashlimit_lock);

	hlist_add_head(&hinfo->node, &hashlimit_htables);

	hlist_add_head(&hinfo->node, &hashlimit_net->htables);

	spin_unlock_bh(&hashlimit_lock);



	return 0;

}



static int htable_create(struct xt_hashlimit_mtinfo1 *minfo, u_int8_t family)

static int htable_create(struct net *net, struct xt_hashlimit_mtinfo1 *minfo,

			 u_int8_t family)

{

	struct hashlimit_net *hashlimit_net = hashlimit_pernet(net);

	struct xt_hashlimit_htable *hinfo;

	unsigned int size;

	unsigned int i;
@@ -301,19 +316,20 @@ static int htable_create(struct xt_hashlimit_mtinfo1 *minfo, u_int8_t family) 


	hinfo->pde = proc_create_data(minfo->name, 0,

		(family == NFPROTO_IPV4) ?

		hashlimit_procdir4 : hashlimit_procdir6,

		hashlimit_net->ipt_hashlimit : hashlimit_net->ip6t_hashlimit,

		&dl_file_ops, hinfo);

	if (hinfo->pde == NULL) {

		vfree(hinfo);

		return -1;

	}

	hinfo->net = net;



	setup_timer(&hinfo->timer, htable_gc, (unsigned long)hinfo);

	hinfo->timer.expires = jiffies + msecs_to_jiffies(hinfo->cfg.gc_interval);

	add_timer(&hinfo->timer);



	spin_lock_bh(&hashlimit_lock);

	hlist_add_head(&hinfo->node, &hashlimit_htables);

	hlist_add_head(&hinfo->node, &hashlimit_net->htables);

	spin_unlock_bh(&hashlimit_lock);



	return 0;
@@ -364,24 +380,30 @@ static void htable_gc(unsigned long htlong) 


static void htable_destroy(struct xt_hashlimit_htable *hinfo)

{

	struct hashlimit_net *hashlimit_net = hashlimit_pernet(hinfo->net);

	struct proc_dir_entry *parent;



	del_timer_sync(&hinfo->timer);



	/* remove proc entry */

	remove_proc_entry(hinfo->pde->name,

			  hinfo->family == NFPROTO_IPV4 ? hashlimit_procdir4 :

						     hashlimit_procdir6);

	if (hinfo->family == NFPROTO_IPV4)

		parent = hashlimit_net->ipt_hashlimit;

	else

		parent = hashlimit_net->ip6t_hashlimit;

	remove_proc_entry(hinfo->pde->name, parent);

	htable_selective_cleanup(hinfo, select_all);

	vfree(hinfo);

}



static struct xt_hashlimit_htable *htable_find_get(const char *name,

static struct xt_hashlimit_htable *htable_find_get(struct net *net,

						   const char *name,

						   u_int8_t family)

{

	struct hashlimit_net *hashlimit_net = hashlimit_pernet(net);

	struct xt_hashlimit_htable *hinfo;

	struct hlist_node *pos;



	spin_lock_bh(&hashlimit_lock);

	hlist_for_each_entry(hinfo, pos, &hashlimit_htables, node) {

	hlist_for_each_entry(hinfo, pos, &hashlimit_net->htables, node) {

		if (!strcmp(name, hinfo->pde->name) &&

		    hinfo->family == family) {

			atomic_inc(&hinfo->use);
@@ -665,6 +687,7 @@ hashlimit_mt(const struct sk_buff *skb, const struct xt_match_param *par) 


static bool hashlimit_mt_check_v0(const struct xt_mtchk_param *par)

{

	struct net *net = par->net;

	struct xt_hashlimit_info *r = par->matchinfo;



	/* Check for overflow. */
@@ -694,8 +717,8 @@ static bool hashlimit_mt_check_v0(const struct xt_mtchk_param *par) 
	 * the list of htable's in htable_create(), since then we would

	 * create duplicate proc files. -HW */

	mutex_lock(&hlimit_mutex);

	r->hinfo = htable_find_get(r->name, par->match->family);

	if (!r->hinfo && htable_create_v0(r, par->match->family) != 0) {

	r->hinfo = htable_find_get(net, r->name, par->match->family);

	if (!r->hinfo && htable_create_v0(net, r, par->match->family) != 0) {

		mutex_unlock(&hlimit_mutex);

		return false;

	}
@@ -706,6 +729,7 @@ static bool hashlimit_mt_check_v0(const struct xt_mtchk_param *par) 


static bool hashlimit_mt_check(const struct xt_mtchk_param *par)

{

	struct net *net = par->net;

	struct xt_hashlimit_mtinfo1 *info = par->matchinfo;



	/* Check for overflow. */
@@ -735,8 +759,8 @@ static bool hashlimit_mt_check(const struct xt_mtchk_param *par) 
	 * the list of htable's in htable_create(), since then we would

	 * create duplicate proc files. -HW */

	mutex_lock(&hlimit_mutex);

	info->hinfo = htable_find_get(info->name, par->match->family);

	if (!info->hinfo && htable_create(info, par->match->family) != 0) {

	info->hinfo = htable_find_get(net, info->name, par->match->family);

	if (!info->hinfo && htable_create(net, info, par->match->family) != 0) {

		mutex_unlock(&hlimit_mutex);

		return false;

	}
@@ -953,10 +977,61 @@ static const struct file_operations dl_file_ops = { 
	.release = seq_release

};



static int __net_init hashlimit_proc_net_init(struct net *net)

{

	struct hashlimit_net *hashlimit_net = hashlimit_pernet(net);



	hashlimit_net->ipt_hashlimit = proc_mkdir("ipt_hashlimit", net->proc_net);

	if (!hashlimit_net->ipt_hashlimit)

		return -ENOMEM;

#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)

	hashlimit_net->ip6t_hashlimit = proc_mkdir("ip6t_hashlimit", net->proc_net);

	if (!hashlimit_net->ip6t_hashlimit) {

		proc_net_remove(net, "ipt_hashlimit");

		return -ENOMEM;

	}

#endif

	return 0;

}



static void __net_exit hashlimit_proc_net_exit(struct net *net)

{

	proc_net_remove(net, "ipt_hashlimit");

#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)

	proc_net_remove(net, "ip6t_hashlimit");

#endif

}



static int __net_init hashlimit_net_init(struct net *net)

{

	struct hashlimit_net *hashlimit_net = hashlimit_pernet(net);



	INIT_HLIST_HEAD(&hashlimit_net->htables);

	return hashlimit_proc_net_init(net);

}



static void __net_exit hashlimit_net_exit(struct net *net)

{

	struct hashlimit_net *hashlimit_net = hashlimit_pernet(net);



	BUG_ON(!hlist_empty(&hashlimit_net->htables));

	hashlimit_proc_net_exit(net);

}



static struct pernet_operations hashlimit_net_ops = {

	.init	= hashlimit_net_init,

	.exit	= hashlimit_net_exit,

	.id	= &hashlimit_net_id,

	.size	= sizeof(struct hashlimit_net),

};



static int __init hashlimit_mt_init(void)

{

	int err;



	err = register_pernet_subsys(&hashlimit_net_ops);

	if (err < 0)

		return err;

	err = xt_register_matches(hashlimit_mt_reg,

	      ARRAY_SIZE(hashlimit_mt_reg));

	if (err < 0)
@@ -970,41 +1045,21 @@ static int __init hashlimit_mt_init(void) 
		printk(KERN_ERR "xt_hashlimit: unable to create slab cache\n");

		goto err2;

	}

	hashlimit_procdir4 = proc_mkdir("ipt_hashlimit", init_net.proc_net);

	if (!hashlimit_procdir4) {

		printk(KERN_ERR "xt_hashlimit: unable to create proc dir "

				"entry\n");

		goto err3;

	}

	err = 0;

#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)

	hashlimit_procdir6 = proc_mkdir("ip6t_hashlimit", init_net.proc_net);

	if (!hashlimit_procdir6) {

		printk(KERN_ERR "xt_hashlimit: unable to create proc dir "

				"entry\n");

		err = -ENOMEM;

	}

#endif

	if (!err)

	return 0;

	remove_proc_entry("ipt_hashlimit", init_net.proc_net);

err3:

	kmem_cache_destroy(hashlimit_cachep);



err2:

	xt_unregister_matches(hashlimit_mt_reg, ARRAY_SIZE(hashlimit_mt_reg));

err1:

	unregister_pernet_subsys(&hashlimit_net_ops);

	return err;



}



static void __exit hashlimit_mt_exit(void)

{

	remove_proc_entry("ipt_hashlimit", init_net.proc_net);

#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)

	remove_proc_entry("ip6t_hashlimit", init_net.proc_net);

#endif

	kmem_cache_destroy(hashlimit_cachep);

	xt_unregister_matches(hashlimit_mt_reg, ARRAY_SIZE(hashlimit_mt_reg));

	unregister_pernet_subsys(&hashlimit_net_ops);

}



module_init(hashlimit_mt_init);

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