[mirror_ubuntu-bionic-kernel.git] / net / bridge / netfilter / ebt_ip.c

/*
 *  ebt_ip
 *
 *	Authors:
 *	Bart De Schuymer <bdschuym@pandora.be>
 *
 *  April, 2002
 *
 *  Changes:
 *    added ip-sport and ip-dport
 *    Innominate Security Technologies AG <mhopf@innominate.com>
 *    September, 2002
 */
#include <linux/ip.h>
#include <net/ip.h>
#include <linux/in.h>
#include <linux/module.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_ip.h>

struct tcpudphdr {
	__be16 src;
	__be16 dst;
};

static bool
ebt_ip_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
	const struct ebt_ip_info *info = par->matchinfo;
	const struct iphdr *ih;
	struct iphdr _iph;
	const struct tcpudphdr *pptr;
	struct tcpudphdr _ports;

	ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
	if (ih == NULL)
		return false;
	if ((info->bitmask & EBT_IP_TOS) &&
	    NF_INVF(info, EBT_IP_TOS, info->tos != ih->tos))
		return false;
	if ((info->bitmask & EBT_IP_SOURCE) &&
	    NF_INVF(info, EBT_IP_SOURCE,
		    (ih->saddr & info->smsk) != info->saddr))
		return false;
	if ((info->bitmask & EBT_IP_DEST) &&
	    NF_INVF(info, EBT_IP_DEST,
		    (ih->daddr & info->dmsk) != info->daddr))
		return false;
	if (info->bitmask & EBT_IP_PROTO) {
		if (NF_INVF(info, EBT_IP_PROTO, info->protocol != ih->protocol))
			return false;
		if (!(info->bitmask & EBT_IP_DPORT) &&
		    !(info->bitmask & EBT_IP_SPORT))
			return true;
		if (ntohs(ih->frag_off) & IP_OFFSET)
			return false;
		pptr = skb_header_pointer(skb, ih->ihl*4,
					  sizeof(_ports), &_ports);
		if (pptr == NULL)
			return false;
		if (info->bitmask & EBT_IP_DPORT) {
			u32 dst = ntohs(pptr->dst);
			if (NF_INVF(info, EBT_IP_DPORT,
				    dst < info->dport[0] ||
				    dst > info->dport[1]))
			return false;
		}
		if (info->bitmask & EBT_IP_SPORT) {
			u32 src = ntohs(pptr->src);
			if (NF_INVF(info, EBT_IP_SPORT,
				    src < info->sport[0] ||
				    src > info->sport[1]))
			return false;
		}
	}
	return true;
}

static int ebt_ip_mt_check(const struct xt_mtchk_param *par)
{
	const struct ebt_ip_info *info = par->matchinfo;
	const struct ebt_entry *e = par->entryinfo;

	if (e->ethproto != htons(ETH_P_IP) ||
	   e->invflags & EBT_IPROTO)
		return -EINVAL;
	if (info->bitmask & ~EBT_IP_MASK || info->invflags & ~EBT_IP_MASK)
		return -EINVAL;
	if (info->bitmask & (EBT_IP_DPORT | EBT_IP_SPORT)) {
		if (info->invflags & EBT_IP_PROTO)
			return -EINVAL;
		if (info->protocol != IPPROTO_TCP &&
		    info->protocol != IPPROTO_UDP &&
		    info->protocol != IPPROTO_UDPLITE &&
		    info->protocol != IPPROTO_SCTP &&
		    info->protocol != IPPROTO_DCCP)
			 return -EINVAL;
	}
	if (info->bitmask & EBT_IP_DPORT && info->dport[0] > info->dport[1])
		return -EINVAL;
	if (info->bitmask & EBT_IP_SPORT && info->sport[0] > info->sport[1])
		return -EINVAL;
	return 0;
}

static struct xt_match ebt_ip_mt_reg __read_mostly = {
	.name		= "ip",
	.revision	= 0,
	.family		= NFPROTO_BRIDGE,
	.match		= ebt_ip_mt,
	.checkentry	= ebt_ip_mt_check,
	.matchsize	= sizeof(struct ebt_ip_info),
	.me		= THIS_MODULE,
};

static int __init ebt_ip_init(void)
{
	return xt_register_match(&ebt_ip_mt_reg);
}

static void __exit ebt_ip_fini(void)
{
	xt_unregister_match(&ebt_ip_mt_reg);
}

module_init(ebt_ip_init);
module_exit(ebt_ip_fini);
MODULE_DESCRIPTION("Ebtables: IPv4 protocol packet match");
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* ebt_ip
	3	*
	4	* Authors:
	5	* Bart De Schuymer <bdschuym@pandora.be>
	6	*
	7	* April, 2002
	8	*
	9	* Changes:
	10	* added ip-sport and ip-dport
	11	* Innominate Security Technologies AG <mhopf@innominate.com>
	12	* September, 2002
	13	*/
1da177e4	14	#include <linux/ip.h>
8a4c8a96	15	#include <net/ip.h>
1da177e4 LT	16	#include <linux/in.h>
1da177e4 LT	17	#include <linux/module.h>
18219d3f JE	18	#include <linux/netfilter/x_tables.h>
	19	#include <linux/netfilter_bridge/ebtables.h>
	20	#include <linux/netfilter_bridge/ebt_ip.h>
1da177e4 LT	21
1da177e4 LT	22	struct tcpudphdr {
47c183fa AV	23	__be16 src;
47c183fa AV	24	__be16 dst;
1da177e4 LT	25	};
1da177e4 LT	26
2d06d4a5	27	static bool
62fc8051	28	ebt_ip_mt(const struct sk_buff skb, struct xt_action_param par)
1da177e4	29	{
f7108a20	30	const struct ebt_ip_info *info = par->matchinfo;
abfdf1c4 JE	31	const struct iphdr *ih;
	32	struct iphdr _iph;
	33	const struct tcpudphdr *pptr;
	34	struct tcpudphdr _ports;
1da177e4 LT	35
	36	ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
	37	if (ih == NULL)
8cc784ee	38	return false;
c37a2dfa JP	39	if ((info->bitmask & EBT_IP_TOS) &&
c37a2dfa JP	40	NF_INVF(info, EBT_IP_TOS, info->tos != ih->tos))
8cc784ee	41	return false;
c37a2dfa JP	42	if ((info->bitmask & EBT_IP_SOURCE) &&
	43	NF_INVF(info, EBT_IP_SOURCE,
	44	(ih->saddr & info->smsk) != info->saddr))
8cc784ee	45	return false;
1da177e4	46	if ((info->bitmask & EBT_IP_DEST) &&
c37a2dfa JP	47	NF_INVF(info, EBT_IP_DEST,
c37a2dfa JP	48	(ih->daddr & info->dmsk) != info->daddr))
8cc784ee	49	return false;
1da177e4	50	if (info->bitmask & EBT_IP_PROTO) {
c37a2dfa	51	if (NF_INVF(info, EBT_IP_PROTO, info->protocol != ih->protocol))
8cc784ee	52	return false;
1da177e4 LT	53	if (!(info->bitmask & EBT_IP_DPORT) &&
1da177e4 LT	54	!(info->bitmask & EBT_IP_SPORT))
8cc784ee	55	return true;
8a4c8a96	56	if (ntohs(ih->frag_off) & IP_OFFSET)
8cc784ee	57	return false;
1da177e4 LT	58	pptr = skb_header_pointer(skb, ih->ihl*4,
	59	sizeof(_ports), &_ports);
	60	if (pptr == NULL)
8cc784ee	61	return false;
1da177e4 LT	62	if (info->bitmask & EBT_IP_DPORT) {
1da177e4 LT	63	u32 dst = ntohs(pptr->dst);
c37a2dfa JP	64	if (NF_INVF(info, EBT_IP_DPORT,
	65	dst < info->dport[0] \|\|
	66	dst > info->dport[1]))
8cc784ee	67	return false;
1da177e4 LT	68	}
	69	if (info->bitmask & EBT_IP_SPORT) {
	70	u32 src = ntohs(pptr->src);
c37a2dfa JP	71	if (NF_INVF(info, EBT_IP_SPORT,
	72	src < info->sport[0] \|\|
	73	src > info->sport[1]))
8cc784ee	74	return false;
1da177e4 LT	75	}
1da177e4 LT	76	}
8cc784ee	77	return true;
1da177e4 LT	78	}
1da177e4 LT	79
b0f38452	80	static int ebt_ip_mt_check(const struct xt_mtchk_param *par)
1da177e4	81	{
9b4fce7a JE	82	const struct ebt_ip_info *info = par->matchinfo;
9b4fce7a JE	83	const struct ebt_entry *e = par->entryinfo;
1da177e4	84
1da177e4 LT	85	if (e->ethproto != htons(ETH_P_IP) \|\|
1da177e4 LT	86	e->invflags & EBT_IPROTO)
bd414ee6	87	return -EINVAL;
1da177e4	88	if (info->bitmask & ~EBT_IP_MASK \|\| info->invflags & ~EBT_IP_MASK)
bd414ee6	89	return -EINVAL;
1da177e4 LT	90	if (info->bitmask & (EBT_IP_DPORT \| EBT_IP_SPORT)) {
1da177e4 LT	91	if (info->invflags & EBT_IP_PROTO)
bd414ee6	92	return -EINVAL;
1da177e4	93	if (info->protocol != IPPROTO_TCP &&
ab67a4d5	94	info->protocol != IPPROTO_UDP &&
a8d0f952	95	info->protocol != IPPROTO_UDPLITE &&
ab67a4d5 PM	96	info->protocol != IPPROTO_SCTP &&
ab67a4d5 PM	97	info->protocol != IPPROTO_DCCP)
bd414ee6	98	return -EINVAL;
1da177e4 LT	99	}
1da177e4 LT	100	if (info->bitmask & EBT_IP_DPORT && info->dport[0] > info->dport[1])
bd414ee6	101	return -EINVAL;
1da177e4	102	if (info->bitmask & EBT_IP_SPORT && info->sport[0] > info->sport[1])
bd414ee6 JE	103	return -EINVAL;
bd414ee6 JE	104	return 0;
1da177e4 LT	105	}
1da177e4 LT	106
043ef46c JE	107	static struct xt_match ebt_ip_mt_reg __read_mostly = {
043ef46c JE	108	.name = "ip",
001a18d3 JE	109	.revision = 0,
001a18d3 JE	110	.family = NFPROTO_BRIDGE,
2d06d4a5 JE	111	.match = ebt_ip_mt,
2d06d4a5 JE	112	.checkentry = ebt_ip_mt_check,
fc0e3df4	113	.matchsize = sizeof(struct ebt_ip_info),
1da177e4 LT	114	.me = THIS_MODULE,
	115	};
	116
65b4b4e8	117	static int __init ebt_ip_init(void)
1da177e4	118	{
043ef46c	119	return xt_register_match(&ebt_ip_mt_reg);
1da177e4 LT	120	}
1da177e4 LT	121
65b4b4e8	122	static void __exit ebt_ip_fini(void)
1da177e4	123	{
043ef46c	124	xt_unregister_match(&ebt_ip_mt_reg);
1da177e4 LT	125	}
1da177e4 LT	126
65b4b4e8 AM	127	module_init(ebt_ip_init);
65b4b4e8 AM	128	module_exit(ebt_ip_fini);
f776c4cd	129	MODULE_DESCRIPTION("Ebtables: IPv4 protocol packet match");
1da177e4	130	MODULE_LICENSE("GPL");