[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / ipv4 / netfilter / ipt_helper.c

/* iptables module to match on related connections */
/*
 * (C) 2001 Martin Josefsson <gandalf@wlug.westbo.se>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *   19 Mar 2002 Harald Welte <laforge@gnumonks.org>:
 *   		 - Port to newnat infrastructure
 */

#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/netfilter.h>
#include <linux/interrupt.h>
#if defined(CONFIG_IP_NF_CONNTRACK) || defined(CONFIG_IP_NF_CONNTRACK_MODULE)
#include <linux/netfilter_ipv4/ip_conntrack.h>
#include <linux/netfilter_ipv4/ip_conntrack_core.h>
#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
#else
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_helper.h>
#endif
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv4/ipt_helper.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Martin Josefsson <gandalf@netfilter.org>");
MODULE_DESCRIPTION("iptables helper match module");

#if 0
#define DEBUGP printk
#else
#define DEBUGP(format, args...)
#endif

#if defined(CONFIG_IP_NF_CONNTRACK) || defined(CONFIG_IP_NF_CONNTRACK_MODULE)
static int
match(const struct sk_buff *skb,
      const struct net_device *in,
      const struct net_device *out,
      const void *matchinfo,
      int offset,
      int *hotdrop)
{
	const struct ipt_helper_info *info = matchinfo;
	struct ip_conntrack *ct;
	enum ip_conntrack_info ctinfo;
	int ret = info->invert;
	
	ct = ip_conntrack_get((struct sk_buff *)skb, &ctinfo);
	if (!ct) {
		DEBUGP("ipt_helper: Eek! invalid conntrack?\n");
		return ret;
	}

	if (!ct->master) {
		DEBUGP("ipt_helper: conntrack %p has no master\n", ct);
		return ret;
	}

	read_lock_bh(&ip_conntrack_lock);
	if (!ct->master->helper) {
		DEBUGP("ipt_helper: master ct %p has no helper\n", 
			exp->expectant);
		goto out_unlock;
	}

	DEBUGP("master's name = %s , info->name = %s\n", 
		ct->master->helper->name, info->name);

	if (info->name[0] == '\0')
		ret ^= 1;
	else
		ret ^= !strncmp(ct->master->helper->name, info->name, 
		                strlen(ct->master->helper->name));
out_unlock:
	read_unlock_bh(&ip_conntrack_lock);
	return ret;
}

#else /* CONFIG_IP_NF_CONNTRACK */

static int
match(const struct sk_buff *skb,
      const struct net_device *in,
      const struct net_device *out,
      const void *matchinfo,
      int offset,
      int *hotdrop)
{
	const struct ipt_helper_info *info = matchinfo;
	struct nf_conn *ct;
	enum ip_conntrack_info ctinfo;
	int ret = info->invert;
	
	ct = nf_ct_get((struct sk_buff *)skb, &ctinfo);
	if (!ct) {
		DEBUGP("ipt_helper: Eek! invalid conntrack?\n");
		return ret;
	}

	if (!ct->master) {
		DEBUGP("ipt_helper: conntrack %p has no master\n", ct);
		return ret;
	}

	read_lock_bh(&nf_conntrack_lock);
	if (!ct->master->helper) {
		DEBUGP("ipt_helper: master ct %p has no helper\n", 
			exp->expectant);
		goto out_unlock;
	}

	DEBUGP("master's name = %s , info->name = %s\n", 
		ct->master->helper->name, info->name);

	if (info->name[0] == '\0')
		ret ^= 1;
	else
		ret ^= !strncmp(ct->master->helper->name, info->name, 
		                strlen(ct->master->helper->name));
out_unlock:
	read_unlock_bh(&nf_conntrack_lock);
	return ret;
}
#endif

static int check(const char *tablename,
		 const struct ipt_ip *ip,
		 void *matchinfo,
		 unsigned int matchsize,
		 unsigned int hook_mask)
{
	struct ipt_helper_info *info = matchinfo;

	info->name[29] = '\0';

	/* verify size */
	if (matchsize != IPT_ALIGN(sizeof(struct ipt_helper_info)))
		return 0;

	return 1;
}

static struct ipt_match helper_match = {
	.name		= "helper",
	.match		= &match,
	.checkentry	= &check,
	.me		= THIS_MODULE,
};

static int __init init(void)
{
	need_ip_conntrack();
	return ipt_register_match(&helper_match);
}

static void __exit fini(void)
{
	ipt_unregister_match(&helper_match);
}

module_init(init);
module_exit(fini);
Commit	Line	Data
1da177e4 LT	1	/* iptables module to match on related connections */
	2	/*
	3	* (C) 2001 Martin Josefsson <gandalf@wlug.westbo.se>
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License version 2 as
	7	* published by the Free Software Foundation.
	8	*
	9	* 19 Mar 2002 Harald Welte <laforge@gnumonks.org>:
	10	* - Port to newnat infrastructure
	11	*/
	12
	13	#include <linux/module.h>
	14	#include <linux/skbuff.h>
	15	#include <linux/netfilter.h>
3cbc4ab5	16	#include <linux/interrupt.h>
9fb9cbb1	17	#if defined(CONFIG_IP_NF_CONNTRACK) \|\| defined(CONFIG_IP_NF_CONNTRACK_MODULE)
1da177e4 LT	18	#include <linux/netfilter_ipv4/ip_conntrack.h>
	19	#include <linux/netfilter_ipv4/ip_conntrack_core.h>
	20	#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
9fb9cbb1 YK	21	#else
	22	#include <net/netfilter/nf_conntrack.h>
	23	#include <net/netfilter/nf_conntrack_core.h>
	24	#include <net/netfilter/nf_conntrack_helper.h>
	25	#endif
1da177e4 LT	26	#include <linux/netfilter_ipv4/ip_tables.h>
	27	#include <linux/netfilter_ipv4/ipt_helper.h>
	28
	29	MODULE_LICENSE("GPL");
	30	MODULE_AUTHOR("Martin Josefsson <gandalf@netfilter.org>");
	31	MODULE_DESCRIPTION("iptables helper match module");
	32
	33	#if 0
	34	#define DEBUGP printk
	35	#else
	36	#define DEBUGP(format, args...)
	37	#endif
	38
9fb9cbb1	39	#if defined(CONFIG_IP_NF_CONNTRACK) \|\| defined(CONFIG_IP_NF_CONNTRACK_MODULE)
1da177e4 LT	40	static int
	41	match(const struct sk_buff *skb,
	42	const struct net_device *in,
	43	const struct net_device *out,
	44	const void *matchinfo,
	45	int offset,
	46	int *hotdrop)
	47	{
	48	const struct ipt_helper_info *info = matchinfo;
	49	struct ip_conntrack *ct;
	50	enum ip_conntrack_info ctinfo;
	51	int ret = info->invert;
	52
	53	ct = ip_conntrack_get((struct sk_buff *)skb, &ctinfo);
	54	if (!ct) {
	55	DEBUGP("ipt_helper: Eek! invalid conntrack?\n");
	56	return ret;
	57	}
	58
	59	if (!ct->master) {
	60	DEBUGP("ipt_helper: conntrack %p has no master\n", ct);
	61	return ret;
	62	}
	63
e45b1be8	64	read_lock_bh(&ip_conntrack_lock);
1da177e4 LT	65	if (!ct->master->helper) {
	66	DEBUGP("ipt_helper: master ct %p has no helper\n",
	67	exp->expectant);
	68	goto out_unlock;
	69	}
	70
	71	DEBUGP("master's name = %s , info->name = %s\n",
	72	ct->master->helper->name, info->name);
	73
	74	if (info->name[0] == '\0')
	75	ret ^= 1;
	76	else
	77	ret ^= !strncmp(ct->master->helper->name, info->name,
	78	strlen(ct->master->helper->name));
	79	out_unlock:
e45b1be8	80	read_unlock_bh(&ip_conntrack_lock);
1da177e4 LT	81	return ret;
	82	}
	83
9fb9cbb1 YK	84	#else /* CONFIG_IP_NF_CONNTRACK */
	85
	86	static int
	87	match(const struct sk_buff *skb,
	88	const struct net_device *in,
	89	const struct net_device *out,
	90	const void *matchinfo,
	91	int offset,
	92	int *hotdrop)
	93	{
	94	const struct ipt_helper_info *info = matchinfo;
	95	struct nf_conn *ct;
	96	enum ip_conntrack_info ctinfo;
	97	int ret = info->invert;
	98
	99	ct = nf_ct_get((struct sk_buff *)skb, &ctinfo);
	100	if (!ct) {
	101	DEBUGP("ipt_helper: Eek! invalid conntrack?\n");
	102	return ret;
	103	}
	104
	105	if (!ct->master) {
	106	DEBUGP("ipt_helper: conntrack %p has no master\n", ct);
	107	return ret;
	108	}
	109
	110	read_lock_bh(&nf_conntrack_lock);
	111	if (!ct->master->helper) {
	112	DEBUGP("ipt_helper: master ct %p has no helper\n",
	113	exp->expectant);
	114	goto out_unlock;
	115	}
	116
	117	DEBUGP("master's name = %s , info->name = %s\n",
	118	ct->master->helper->name, info->name);
	119
	120	if (info->name[0] == '\0')
	121	ret ^= 1;
	122	else
	123	ret ^= !strncmp(ct->master->helper->name, info->name,
	124	strlen(ct->master->helper->name));
	125	out_unlock:
	126	read_unlock_bh(&nf_conntrack_lock);
	127	return ret;
	128	}
	129	#endif
	130
1da177e4 LT	131	static int check(const char *tablename,
	132	const struct ipt_ip *ip,
	133	void *matchinfo,
	134	unsigned int matchsize,
	135	unsigned int hook_mask)
	136	{
	137	struct ipt_helper_info *info = matchinfo;
	138
	139	info->name[29] = '\0';
	140
	141	/* verify size */
	142	if (matchsize != IPT_ALIGN(sizeof(struct ipt_helper_info)))
	143	return 0;
	144
	145	return 1;
	146	}
	147
	148	static struct ipt_match helper_match = {
	149	.name = "helper",
	150	.match = &match,
	151	.checkentry = &check,
	152	.me = THIS_MODULE,
	153	};
	154
	155	static int __init init(void)
	156	{
	157	need_ip_conntrack();
	158	return ipt_register_match(&helper_match);
	159	}
	160
	161	static void __exit fini(void)
	162	{
	163	ipt_unregister_match(&helper_match);
	164	}
	165
	166	module_init(init);
	167	module_exit(fini);
	168