[linux-2.6-block.git] / net / bridge / netfilter / ebt_ip6.c

/*
 *  ebt_ip6
 *
 *	Authors:
 *	Manohar Castelino <manohar.r.castelino@intel.com>
 *	Kuo-Lang Tseng <kuo-lang.tseng@intel.com>
 *	Jan Engelhardt <jengelh@medozas.de>
 *
 * Summary:
 * This is just a modification of the IPv4 code written by
 * Bart De Schuymer <bdschuym@pandora.be>
 * with the changes required to support IPv6
 *
 *  Jan, 2008
 */
#include <linux/ipv6.h>
#include <net/ipv6.h>
#include <linux/in.h>
#include <linux/module.h>
#include <net/dsfield.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_ip6.h>

union pkthdr {
	struct {
		__be16 src;
		__be16 dst;
	} tcpudphdr;
	struct {
		u8 type;
		u8 code;
	} icmphdr;
};

static bool
ebt_ip6_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
	const struct ebt_ip6_info *info = par->matchinfo;
	const struct ipv6hdr *ih6;
	struct ipv6hdr _ip6h;
	const union pkthdr *pptr;
	union pkthdr _pkthdr;

	ih6 = skb_header_pointer(skb, 0, sizeof(_ip6h), &_ip6h);
	if (ih6 == NULL)
		return false;
	if (info->bitmask & EBT_IP6_TCLASS &&
	   FWINV(info->tclass != ipv6_get_dsfield(ih6), EBT_IP6_TCLASS))
		return false;
	if ((info->bitmask & EBT_IP6_SOURCE &&
	    FWINV(ipv6_masked_addr_cmp(&ih6->saddr, &info->smsk,
				       &info->saddr), EBT_IP6_SOURCE)) ||
	    (info->bitmask & EBT_IP6_DEST &&
	    FWINV(ipv6_masked_addr_cmp(&ih6->daddr, &info->dmsk,
				       &info->daddr), EBT_IP6_DEST)))
		return false;
	if (info->bitmask & EBT_IP6_PROTO) {
		uint8_t nexthdr = ih6->nexthdr;
		__be16 frag_off;
		int offset_ph;

		offset_ph = ipv6_skip_exthdr(skb, sizeof(_ip6h), &nexthdr, &frag_off);
		if (offset_ph == -1)
			return false;
		if (FWINV(info->protocol != nexthdr, EBT_IP6_PROTO))
			return false;
		if (!(info->bitmask & ( EBT_IP6_DPORT |
					EBT_IP6_SPORT | EBT_IP6_ICMP6)))
			return true;

		/* min icmpv6 headersize is 4, so sizeof(_pkthdr) is ok. */
		pptr = skb_header_pointer(skb, offset_ph, sizeof(_pkthdr),
					  &_pkthdr);
		if (pptr == NULL)
			return false;
		if (info->bitmask & EBT_IP6_DPORT) {
			u16 dst = ntohs(pptr->tcpudphdr.dst);
			if (FWINV(dst < info->dport[0] ||
				  dst > info->dport[1], EBT_IP6_DPORT))
				return false;
		}
		if (info->bitmask & EBT_IP6_SPORT) {
			u16 src = ntohs(pptr->tcpudphdr.src);
			if (FWINV(src < info->sport[0] ||
				  src > info->sport[1], EBT_IP6_SPORT))
			return false;
		}
		if ((info->bitmask & EBT_IP6_ICMP6) &&
		     FWINV(pptr->icmphdr.type < info->icmpv6_type[0] ||
			   pptr->icmphdr.type > info->icmpv6_type[1] ||
			   pptr->icmphdr.code < info->icmpv6_code[0] ||
			   pptr->icmphdr.code > info->icmpv6_code[1],
							EBT_IP6_ICMP6))
			return false;
	}
	return true;
}

static int ebt_ip6_mt_check(const struct xt_mtchk_param *par)
{
	const struct ebt_entry *e = par->entryinfo;
	struct ebt_ip6_info *info = par->matchinfo;

	if (e->ethproto != htons(ETH_P_IPV6) || e->invflags & EBT_IPROTO)
		return -EINVAL;
	if (info->bitmask & ~EBT_IP6_MASK || info->invflags & ~EBT_IP6_MASK)
		return -EINVAL;
	if (info->bitmask & (EBT_IP6_DPORT | EBT_IP6_SPORT)) {
		if (info->invflags & EBT_IP6_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_IP6_DPORT && info->dport[0] > info->dport[1])
		return -EINVAL;
	if (info->bitmask & EBT_IP6_SPORT && info->sport[0] > info->sport[1])
		return -EINVAL;
	if (info->bitmask & EBT_IP6_ICMP6) {
		if ((info->invflags & EBT_IP6_PROTO) ||
		     info->protocol != IPPROTO_ICMPV6)
			return -EINVAL;
		if (info->icmpv6_type[0] > info->icmpv6_type[1] ||
		    info->icmpv6_code[0] > info->icmpv6_code[1])
			return -EINVAL;
	}
	return 0;
}

static struct xt_match ebt_ip6_mt_reg __read_mostly = {
	.name		= "ip6",
	.revision	= 0,
	.family		= NFPROTO_BRIDGE,
	.match		= ebt_ip6_mt,
	.checkentry	= ebt_ip6_mt_check,
	.matchsize	= sizeof(struct ebt_ip6_info),
	.me		= THIS_MODULE,
};

static int __init ebt_ip6_init(void)
{
	return xt_register_match(&ebt_ip6_mt_reg);
}

static void __exit ebt_ip6_fini(void)
{
	xt_unregister_match(&ebt_ip6_mt_reg);
}

module_init(ebt_ip6_init);
module_exit(ebt_ip6_fini);
MODULE_DESCRIPTION("Ebtables: IPv6 protocol packet match");
MODULE_AUTHOR("Kuo-Lang Tseng <kuo-lang.tseng@intel.com>");
MODULE_LICENSE("GPL");
Commit	Line	Data
93f65158 KT	1	/*
	2	* ebt_ip6
	3	*
	4	* Authors:
	5	* Manohar Castelino <manohar.r.castelino@intel.com>
	6	* Kuo-Lang Tseng <kuo-lang.tseng@intel.com>
408ffaa4	7	* Jan Engelhardt <jengelh@medozas.de>
93f65158 KT	8	*
	9	* Summary:
	10	* This is just a modification of the IPv4 code written by
	11	* Bart De Schuymer <bdschuym@pandora.be>
	12	* with the changes required to support IPv6
	13	*
	14	* Jan, 2008
	15	*/
93f65158 KT	16	#include <linux/ipv6.h>
	17	#include <net/ipv6.h>
	18	#include <linux/in.h>
	19	#include <linux/module.h>
	20	#include <net/dsfield.h>
18219d3f JE	21	#include <linux/netfilter/x_tables.h>
	22	#include <linux/netfilter_bridge/ebtables.h>
	23	#include <linux/netfilter_bridge/ebt_ip6.h>
93f65158	24
6faee60a FW	25	union pkthdr {
	26	struct {
	27	__be16 src;
	28	__be16 dst;
	29	} tcpudphdr;
	30	struct {
	31	u8 type;
	32	u8 code;
	33	} icmphdr;
93f65158 KT	34	};
93f65158 KT	35
2d06d4a5	36	static bool
62fc8051	37	ebt_ip6_mt(const struct sk_buff skb, struct xt_action_param par)
93f65158	38	{
f7108a20	39	const struct ebt_ip6_info *info = par->matchinfo;
93f65158 KT	40	const struct ipv6hdr *ih6;
93f65158 KT	41	struct ipv6hdr _ip6h;
6faee60a FW	42	const union pkthdr *pptr;
6faee60a FW	43	union pkthdr _pkthdr;
93f65158 KT	44
	45	ih6 = skb_header_pointer(skb, 0, sizeof(_ip6h), &_ip6h);
	46	if (ih6 == NULL)
8cc784ee	47	return false;
93f65158 KT	48	if (info->bitmask & EBT_IP6_TCLASS &&
93f65158 KT	49	FWINV(info->tclass != ipv6_get_dsfield(ih6), EBT_IP6_TCLASS))
8cc784ee	50	return false;
acab78b9 LFCE	51	if ((info->bitmask & EBT_IP6_SOURCE &&
	52	FWINV(ipv6_masked_addr_cmp(&ih6->saddr, &info->smsk,
	53	&info->saddr), EBT_IP6_SOURCE)) \|\|
	54	(info->bitmask & EBT_IP6_DEST &&
0898f99a	55	FWINV(ipv6_masked_addr_cmp(&ih6->daddr, &info->dmsk,
acab78b9	56	&info->daddr), EBT_IP6_DEST)))
8cc784ee	57	return false;
93f65158 KT	58	if (info->bitmask & EBT_IP6_PROTO) {
93f65158 KT	59	uint8_t nexthdr = ih6->nexthdr;
75f2811c	60	__be16 frag_off;
93f65158 KT	61	int offset_ph;
93f65158 KT	62
75f2811c	63	offset_ph = ipv6_skip_exthdr(skb, sizeof(_ip6h), &nexthdr, &frag_off);
93f65158	64	if (offset_ph == -1)
8cc784ee	65	return false;
93f65158	66	if (FWINV(info->protocol != nexthdr, EBT_IP6_PROTO))
8cc784ee	67	return false;
6faee60a FW	68	if (!(info->bitmask & ( EBT_IP6_DPORT \|
6faee60a FW	69	EBT_IP6_SPORT \| EBT_IP6_ICMP6)))
8cc784ee	70	return true;
6faee60a FW	71
	72	/* min icmpv6 headersize is 4, so sizeof(_pkthdr) is ok. */
	73	pptr = skb_header_pointer(skb, offset_ph, sizeof(_pkthdr),
	74	&_pkthdr);
93f65158	75	if (pptr == NULL)
8cc784ee	76	return false;
93f65158	77	if (info->bitmask & EBT_IP6_DPORT) {
6faee60a	78	u16 dst = ntohs(pptr->tcpudphdr.dst);
93f65158 KT	79	if (FWINV(dst < info->dport[0] \|\|
93f65158 KT	80	dst > info->dport[1], EBT_IP6_DPORT))
8cc784ee	81	return false;
93f65158 KT	82	}
93f65158 KT	83	if (info->bitmask & EBT_IP6_SPORT) {
6faee60a	84	u16 src = ntohs(pptr->tcpudphdr.src);
93f65158 KT	85	if (FWINV(src < info->sport[0] \|\|
93f65158 KT	86	src > info->sport[1], EBT_IP6_SPORT))
8cc784ee	87	return false;
93f65158	88	}
6faee60a FW	89	if ((info->bitmask & EBT_IP6_ICMP6) &&
	90	FWINV(pptr->icmphdr.type < info->icmpv6_type[0] \|\|
	91	pptr->icmphdr.type > info->icmpv6_type[1] \|\|
	92	pptr->icmphdr.code < info->icmpv6_code[0] \|\|
	93	pptr->icmphdr.code > info->icmpv6_code[1],
	94	EBT_IP6_ICMP6))
	95	return false;
93f65158	96	}
8cc784ee	97	return true;
93f65158 KT	98	}
93f65158 KT	99
b0f38452	100	static int ebt_ip6_mt_check(const struct xt_mtchk_param *par)
93f65158	101	{
9b4fce7a JE	102	const struct ebt_entry *e = par->entryinfo;
9b4fce7a JE	103	struct ebt_ip6_info *info = par->matchinfo;
93f65158	104
93f65158	105	if (e->ethproto != htons(ETH_P_IPV6) \|\| e->invflags & EBT_IPROTO)
bd414ee6	106	return -EINVAL;
93f65158	107	if (info->bitmask & ~EBT_IP6_MASK \|\| info->invflags & ~EBT_IP6_MASK)
bd414ee6	108	return -EINVAL;
93f65158 KT	109	if (info->bitmask & (EBT_IP6_DPORT \| EBT_IP6_SPORT)) {
93f65158 KT	110	if (info->invflags & EBT_IP6_PROTO)
bd414ee6	111	return -EINVAL;
93f65158 KT	112	if (info->protocol != IPPROTO_TCP &&
	113	info->protocol != IPPROTO_UDP &&
	114	info->protocol != IPPROTO_UDPLITE &&
	115	info->protocol != IPPROTO_SCTP &&
	116	info->protocol != IPPROTO_DCCP)
bd414ee6	117	return -EINVAL;
93f65158 KT	118	}
93f65158 KT	119	if (info->bitmask & EBT_IP6_DPORT && info->dport[0] > info->dport[1])
bd414ee6	120	return -EINVAL;
93f65158	121	if (info->bitmask & EBT_IP6_SPORT && info->sport[0] > info->sport[1])
bd414ee6	122	return -EINVAL;
6faee60a FW	123	if (info->bitmask & EBT_IP6_ICMP6) {
	124	if ((info->invflags & EBT_IP6_PROTO) \|\|
	125	info->protocol != IPPROTO_ICMPV6)
	126	return -EINVAL;
	127	if (info->icmpv6_type[0] > info->icmpv6_type[1] \|\|
	128	info->icmpv6_code[0] > info->icmpv6_code[1])
	129	return -EINVAL;
	130	}
bd414ee6	131	return 0;
93f65158 KT	132	}
93f65158 KT	133
043ef46c JE	134	static struct xt_match ebt_ip6_mt_reg __read_mostly = {
043ef46c JE	135	.name = "ip6",
001a18d3 JE	136	.revision = 0,
001a18d3 JE	137	.family = NFPROTO_BRIDGE,
2d06d4a5 JE	138	.match = ebt_ip6_mt,
2d06d4a5 JE	139	.checkentry = ebt_ip6_mt_check,
fc0e3df4	140	.matchsize = sizeof(struct ebt_ip6_info),
93f65158 KT	141	.me = THIS_MODULE,
	142	};
	143
	144	static int __init ebt_ip6_init(void)
	145	{
043ef46c	146	return xt_register_match(&ebt_ip6_mt_reg);
93f65158 KT	147	}
	148
	149	static void __exit ebt_ip6_fini(void)
	150	{
043ef46c	151	xt_unregister_match(&ebt_ip6_mt_reg);
93f65158 KT	152	}
	153
	154	module_init(ebt_ip6_init);
	155	module_exit(ebt_ip6_fini);
	156	MODULE_DESCRIPTION("Ebtables: IPv6 protocol packet match");
8244f4ba	157	MODULE_AUTHOR("Kuo-Lang Tseng <kuo-lang.tseng@intel.com>");
93f65158	158	MODULE_LICENSE("GPL");