[net-next-2.6.git] / net / ipv6 / netfilter.c

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/ipv6.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv6.h>
#include <net/dst.h>
#include <net/ipv6.h>
#include <net/ip6_route.h>
#include <net/xfrm.h>
#include <net/ip6_checksum.h>

int ip6_route_me_harder(struct sk_buff *skb)
{
	struct ipv6hdr *iph = ipv6_hdr(skb);
	struct dst_entry *dst;
	struct flowi fl = {
		.oif = skb->sk ? skb->sk->sk_bound_dev_if : 0,
		.mark = skb->mark,
		.nl_u =
		{ .ip6_u =
		  { .daddr = iph->daddr,
		    .saddr = iph->saddr, } },
	};

	dst = ip6_route_output(skb->sk, &fl);

#ifdef CONFIG_XFRM
	if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
	    xfrm_decode_session(skb, &fl, AF_INET6) == 0)
		if (xfrm_lookup(&skb->dst, &fl, skb->sk, 0))
			return -1;
#endif

	if (dst->error) {
		IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
		LIMIT_NETDEBUG(KERN_DEBUG "ip6_route_me_harder: No more route.\n");
		dst_release(dst);
		return -EINVAL;
	}

	/* Drop old route. */
	dst_release(skb->dst);

	skb->dst = dst;
	return 0;
}
EXPORT_SYMBOL(ip6_route_me_harder);

/*
 * Extra routing may needed on local out, as the QUEUE target never
 * returns control to the table.
 */

struct ip6_rt_info {
	struct in6_addr daddr;
	struct in6_addr saddr;
};

static void nf_ip6_saveroute(const struct sk_buff *skb, struct nf_info *info)
{
	struct ip6_rt_info *rt_info = nf_info_reroute(info);

	if (info->hook == NF_INET_LOCAL_OUT) {
		struct ipv6hdr *iph = ipv6_hdr(skb);

		rt_info->daddr = iph->daddr;
		rt_info->saddr = iph->saddr;
	}
}

static int nf_ip6_reroute(struct sk_buff *skb, const struct nf_info *info)
{
	struct ip6_rt_info *rt_info = nf_info_reroute(info);

	if (info->hook == NF_INET_LOCAL_OUT) {
		struct ipv6hdr *iph = ipv6_hdr(skb);
		if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) ||
		    !ipv6_addr_equal(&iph->saddr, &rt_info->saddr))
			return ip6_route_me_harder(skb);
	}
	return 0;
}

static int nf_ip6_route(struct dst_entry **dst, struct flowi *fl)
{
	*dst = ip6_route_output(NULL, fl);
	return (*dst)->error;
}

__sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,
			     unsigned int dataoff, u_int8_t protocol)
{
	struct ipv6hdr *ip6h = ipv6_hdr(skb);
	__sum16 csum = 0;

	switch (skb->ip_summed) {
	case CHECKSUM_COMPLETE:
		if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN)
			break;
		if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
				     skb->len - dataoff, protocol,
				     csum_sub(skb->csum,
					      skb_checksum(skb, 0,
							   dataoff, 0)))) {
			skb->ip_summed = CHECKSUM_UNNECESSARY;
			break;
		}
		/* fall through */
	case CHECKSUM_NONE:
		skb->csum = ~csum_unfold(
				csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
					     skb->len - dataoff,
					     protocol,
					     csum_sub(0,
						      skb_checksum(skb, 0,
								   dataoff, 0))));
		csum = __skb_checksum_complete(skb);
	}
	return csum;
}

EXPORT_SYMBOL(nf_ip6_checksum);

static struct nf_afinfo nf_ip6_afinfo = {
	.family		= AF_INET6,
	.checksum	= nf_ip6_checksum,
	.route		= nf_ip6_route,
	.saveroute	= nf_ip6_saveroute,
	.reroute	= nf_ip6_reroute,
	.route_key_size	= sizeof(struct ip6_rt_info),
};

int __init ipv6_netfilter_init(void)
{
	return nf_register_afinfo(&nf_ip6_afinfo);
}

/* This can be called from inet6_init() on errors, so it cannot
 * be marked __exit. -DaveM
 */
void ipv6_netfilter_fini(void)
{
	nf_unregister_afinfo(&nf_ip6_afinfo);
}
Commit	Line	Data
020b4c12	1	#include <linux/kernel.h>
bb94aa16	2	#include <linux/init.h>
020b4c12	3	#include <linux/ipv6.h>
2cc7d573 HW	4	#include <linux/netfilter.h>
2cc7d573 HW	5	#include <linux/netfilter_ipv6.h>
020b4c12 HW	6	#include <net/dst.h>
	7	#include <net/ipv6.h>
	8	#include <net/ip6_route.h>
3e3850e9	9	#include <net/xfrm.h>
503e4faa	10	#include <net/ip6_checksum.h>
020b4c12 HW	11
	12	int ip6_route_me_harder(struct sk_buff *skb)
	13	{
0660e03f	14	struct ipv6hdr *iph = ipv6_hdr(skb);
020b4c12 HW	15	struct dst_entry *dst;
	16	struct flowi fl = {
	17	.oif = skb->sk ? skb->sk->sk_bound_dev_if : 0,
bc5f7743	18	.mark = skb->mark,
020b4c12 HW	19	.nl_u =
	20	{ .ip6_u =
	21	{ .daddr = iph->daddr,
	22	.saddr = iph->saddr, } },
020b4c12 HW	23	};
	24
	25	dst = ip6_route_output(skb->sk, &fl);
	26
3e3850e9 PM	27	#ifdef CONFIG_XFRM
	28	if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
	29	xfrm_decode_session(skb, &fl, AF_INET6) == 0)
	30	if (xfrm_lookup(&skb->dst, &fl, skb->sk, 0))
	31	return -1;
	32	#endif
	33
020b4c12	34	if (dst->error) {
a11d206d	35	IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
64ce2073	36	LIMIT_NETDEBUG(KERN_DEBUG "ip6_route_me_harder: No more route.\n");
020b4c12 HW	37	dst_release(dst);
	38	return -EINVAL;
	39	}
	40
	41	/* Drop old route. */
	42	dst_release(skb->dst);
	43
	44	skb->dst = dst;
	45	return 0;
	46	}
	47	EXPORT_SYMBOL(ip6_route_me_harder);
	48
2cc7d573 HW	49	/*
	50	* Extra routing may needed on local out, as the QUEUE target never
	51	* returns control to the table.
	52	*/
	53
	54	struct ip6_rt_info {
	55	struct in6_addr daddr;
	56	struct in6_addr saddr;
	57	};
	58
bce8032e	59	static void nf_ip6_saveroute(const struct sk_buff skb, struct nf_info info)
2cc7d573 HW	60	{
	61	struct ip6_rt_info *rt_info = nf_info_reroute(info);
	62
6e23ae2a	63	if (info->hook == NF_INET_LOCAL_OUT) {
0660e03f	64	struct ipv6hdr *iph = ipv6_hdr(skb);
2cc7d573 HW	65
	66	rt_info->daddr = iph->daddr;
	67	rt_info->saddr = iph->saddr;
	68	}
	69	}
	70
3db05fea	71	static int nf_ip6_reroute(struct sk_buff skb, const struct nf_info info)
2cc7d573 HW	72	{
	73	struct ip6_rt_info *rt_info = nf_info_reroute(info);
	74
6e23ae2a	75	if (info->hook == NF_INET_LOCAL_OUT) {
3db05fea	76	struct ipv6hdr *iph = ipv6_hdr(skb);
2cc7d573 HW	77	if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) \|\|
2cc7d573 HW	78	!ipv6_addr_equal(&iph->saddr, &rt_info->saddr))
3db05fea	79	return ip6_route_me_harder(skb);
2cc7d573 HW	80	}
	81	return 0;
	82	}
	83
1841a4c7 PM	84	static int nf_ip6_route(struct dst_entry *dst, struct flowi fl)
	85	{
	86	*dst = ip6_route_output(NULL, fl);
	87	return (*dst)->error;
	88	}
	89
b51655b9	90	__sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,
422c346f PM	91	unsigned int dataoff, u_int8_t protocol)
422c346f PM	92	{
0660e03f	93	struct ipv6hdr *ip6h = ipv6_hdr(skb);
b51655b9	94	__sum16 csum = 0;
422c346f PM	95
422c346f PM	96	switch (skb->ip_summed) {
84fa7933	97	case CHECKSUM_COMPLETE:
6e23ae2a	98	if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN)
422c346f PM	99	break;
422c346f PM	100	if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
1ab1457c	101	skb->len - dataoff, protocol,
422c346f PM	102	csum_sub(skb->csum,
	103	skb_checksum(skb, 0,
	104	dataoff, 0)))) {
	105	skb->ip_summed = CHECKSUM_UNNECESSARY;
	106	break;
	107	}
	108	/* fall through */
	109	case CHECKSUM_NONE:
868c86bc AV	110	skb->csum = ~csum_unfold(
868c86bc AV	111	csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
422c346f PM	112	skb->len - dataoff,
	113	protocol,
	114	csum_sub(0,
	115	skb_checksum(skb, 0,
1ab1457c	116	dataoff, 0))));
422c346f PM	117	csum = __skb_checksum_complete(skb);
	118	}
	119	return csum;
	120	}
	121
	122	EXPORT_SYMBOL(nf_ip6_checksum);
	123
bce8032e PM	124	static struct nf_afinfo nf_ip6_afinfo = {
bce8032e PM	125	.family = AF_INET6,
422c346f	126	.checksum = nf_ip6_checksum,
1841a4c7	127	.route = nf_ip6_route,
bce8032e PM	128	.saveroute = nf_ip6_saveroute,
	129	.reroute = nf_ip6_reroute,
	130	.route_key_size = sizeof(struct ip6_rt_info),
2cc7d573 HW	131	};
	132
	133	int __init ipv6_netfilter_init(void)
	134	{
bce8032e	135	return nf_register_afinfo(&nf_ip6_afinfo);
2cc7d573 HW	136	}
2cc7d573 HW	137
5bf887f2 DM	138	/* This can be called from inet6_init() on errors, so it cannot
	139	* be marked __exit. -DaveM
	140	*/
	141	void ipv6_netfilter_fini(void)
2cc7d573	142	{
bce8032e	143	nf_unregister_afinfo(&nf_ip6_afinfo);
2cc7d573	144	}