[deliverable/linux.git] / net / ipv6 / xfrm6_input.c

/*
 * xfrm6_input.c: based on net/ipv4/xfrm4_input.c
 *
 * Authors:
 *	Mitsuru KANDA @USAGI
 * 	Kazunori MIYAZAWA @USAGI
 * 	Kunihiro Ishiguro <kunihiro@ipinfusion.com>
 *	YOSHIFUJI Hideaki @USAGI
 *		IPv6 support
 */

#include <linux/module.h>
#include <linux/string.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv6.h>
#include <net/ipv6.h>
#include <net/xfrm.h>

int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi)
{
	int err;
	__be32 seq;
	struct xfrm_state *xfrm_vec[XFRM_MAX_DEPTH];
	struct xfrm_state *x;
	int xfrm_nr = 0;
	int decaps = 0;
	unsigned int nhoff;

	nhoff = IP6CB(skb)->nhoff;

	seq = 0;
	if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0)
		goto drop;

	do {
		struct ipv6hdr *iph = ipv6_hdr(skb);

		if (xfrm_nr == XFRM_MAX_DEPTH)
			goto drop;

		x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi,
				      nexthdr, AF_INET6);
		if (x == NULL)
			goto drop;
		spin_lock(&x->lock);
		if (unlikely(x->km.state != XFRM_STATE_VALID))
			goto drop_unlock;

		if (x->props.replay_window && xfrm_replay_check(x, seq))
			goto drop_unlock;

		if (xfrm_state_check_expire(x))
			goto drop_unlock;

		nexthdr = x->type->input(x, skb);
		if (nexthdr <= 0)
			goto drop_unlock;

		skb_network_header(skb)[nhoff] = nexthdr;

		if (x->props.replay_window)
			xfrm_replay_advance(x, seq);

		x->curlft.bytes += skb->len;
		x->curlft.packets++;

		spin_unlock(&x->lock);

		xfrm_vec[xfrm_nr++] = x;

		if (x->outer_mode->input(x, skb))
			goto drop;

		if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) {
			decaps = 1;
			break;
		}

		if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) < 0)
			goto drop;
	} while (!err);

	/* Allocate new secpath or COW existing one. */
	if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
		struct sec_path *sp;
		sp = secpath_dup(skb->sp);
		if (!sp)
			goto drop;
		if (skb->sp)
			secpath_put(skb->sp);
		skb->sp = sp;
	}

	if (xfrm_nr + skb->sp->len > XFRM_MAX_DEPTH)
		goto drop;

	memcpy(skb->sp->xvec + skb->sp->len, xfrm_vec,
	       xfrm_nr * sizeof(xfrm_vec[0]));
	skb->sp->len += xfrm_nr;

	nf_reset(skb);

	if (decaps) {
		dst_release(skb->dst);
		skb->dst = NULL;
		netif_rx(skb);
		return -1;
	} else {
#ifdef CONFIG_NETFILTER
		ipv6_hdr(skb)->payload_len = htons(skb->len);
		__skb_push(skb, skb->data - skb_network_header(skb));

		NF_HOOK(PF_INET6, NF_IP6_PRE_ROUTING, skb, skb->dev, NULL,
			ip6_rcv_finish);
		return -1;
#else
		return 1;
#endif
	}

drop_unlock:
	spin_unlock(&x->lock);
	xfrm_state_put(x);
drop:
	while (--xfrm_nr >= 0)
		xfrm_state_put(xfrm_vec[xfrm_nr]);
	kfree_skb(skb);
	return -1;
}

EXPORT_SYMBOL(xfrm6_rcv_spi);

int xfrm6_rcv(struct sk_buff *skb)
{
	return xfrm6_rcv_spi(skb, skb_network_header(skb)[IP6CB(skb)->nhoff],
			     0);
}

EXPORT_SYMBOL(xfrm6_rcv);

int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
		     xfrm_address_t *saddr, u8 proto)
{
	struct xfrm_state *x = NULL;
	int wildcard = 0;
	xfrm_address_t *xany;
	struct xfrm_state *xfrm_vec_one = NULL;
	int nh = 0;
	int i = 0;

	xany = (xfrm_address_t *)&in6addr_any;

	for (i = 0; i < 3; i++) {
		xfrm_address_t *dst, *src;
		switch (i) {
		case 0:
			dst = daddr;
			src = saddr;
			break;
		case 1:
			/* lookup state with wild-card source address */
			wildcard = 1;
			dst = daddr;
			src = xany;
			break;
		case 2:
		default:
			/* lookup state with wild-card addresses */
			wildcard = 1; /* XXX */
			dst = xany;
			src = xany;
			break;
		}

		x = xfrm_state_lookup_byaddr(dst, src, proto, AF_INET6);
		if (!x)
			continue;

		spin_lock(&x->lock);

		if (wildcard) {
			if ((x->props.flags & XFRM_STATE_WILDRECV) == 0) {
				spin_unlock(&x->lock);
				xfrm_state_put(x);
				x = NULL;
				continue;
			}
		}

		if (unlikely(x->km.state != XFRM_STATE_VALID)) {
			spin_unlock(&x->lock);
			xfrm_state_put(x);
			x = NULL;
			continue;
		}
		if (xfrm_state_check_expire(x)) {
			spin_unlock(&x->lock);
			xfrm_state_put(x);
			x = NULL;
			continue;
		}

		nh = x->type->input(x, skb);
		if (nh <= 0) {
			spin_unlock(&x->lock);
			xfrm_state_put(x);
			x = NULL;
			continue;
		}

		x->curlft.bytes += skb->len;
		x->curlft.packets++;

		spin_unlock(&x->lock);

		xfrm_vec_one = x;
		break;
	}

	if (!xfrm_vec_one)
		goto drop;

	/* Allocate new secpath or COW existing one. */
	if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
		struct sec_path *sp;
		sp = secpath_dup(skb->sp);
		if (!sp)
			goto drop;
		if (skb->sp)
			secpath_put(skb->sp);
		skb->sp = sp;
	}

	if (1 + skb->sp->len > XFRM_MAX_DEPTH)
		goto drop;

	skb->sp->xvec[skb->sp->len] = xfrm_vec_one;
	skb->sp->len ++;

	return 1;
drop:
	if (xfrm_vec_one)
		xfrm_state_put(xfrm_vec_one);
	return -1;
}

EXPORT_SYMBOL(xfrm6_input_addr);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* xfrm6_input.c: based on net/ipv4/xfrm4_input.c
	3	*
	4	* Authors:
	5	* Mitsuru KANDA @USAGI
	6	* Kazunori MIYAZAWA @USAGI
	7	* Kunihiro Ishiguro <kunihiro@ipinfusion.com>
	8	* YOSHIFUJI Hideaki @USAGI
	9	* IPv6 support
	10	*/
	11
	12	#include <linux/module.h>
	13	#include <linux/string.h>
b05e1066 PM	14	#include <linux/netfilter.h>
b05e1066 PM	15	#include <linux/netfilter_ipv6.h>
1da177e4 LT	16	#include <net/ipv6.h>
	17	#include <net/xfrm.h>
	18
33b5ecb8	19	int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi)
1da177e4	20	{
1da177e4	21	int err;
6067b2ba	22	__be32 seq;
dbe5b4aa	23	struct xfrm_state *xfrm_vec[XFRM_MAX_DEPTH];
1da177e4 LT	24	struct xfrm_state *x;
	25	int xfrm_nr = 0;
	26	int decaps = 0;
1da177e4 LT	27	unsigned int nhoff;
1da177e4 LT	28
951dbc8a	29	nhoff = IP6CB(skb)->nhoff;
1da177e4 LT	30
	31	seq = 0;
	32	if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0)
	33	goto drop;
1ab1457c	34
1da177e4	35	do {
0660e03f	36	struct ipv6hdr *iph = ipv6_hdr(skb);
1da177e4 LT	37
	38	if (xfrm_nr == XFRM_MAX_DEPTH)
	39	goto drop;
	40
73d605d1	41	x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi,
33b5ecb8	42	nexthdr, AF_INET6);
1da177e4 LT	43	if (x == NULL)
	44	goto drop;
	45	spin_lock(&x->lock);
	46	if (unlikely(x->km.state != XFRM_STATE_VALID))
	47	goto drop_unlock;
	48
	49	if (x->props.replay_window && xfrm_replay_check(x, seq))
	50	goto drop_unlock;
	51
	52	if (xfrm_state_check_expire(x))
	53	goto drop_unlock;
	54
e695633e	55	nexthdr = x->type->input(x, skb);
1da177e4 LT	56	if (nexthdr <= 0)
	57	goto drop_unlock;
	58
d56f90a7	59	skb_network_header(skb)[nhoff] = nexthdr;
1da177e4 LT	60
	61	if (x->props.replay_window)
	62	xfrm_replay_advance(x, seq);
	63
	64	x->curlft.bytes += skb->len;
	65	x->curlft.packets++;
	66
	67	spin_unlock(&x->lock);
	68
dbe5b4aa	69	xfrm_vec[xfrm_nr++] = x;
1da177e4	70
13996378	71	if (x->outer_mode->input(x, skb))
b59f45d0 HX	72	goto drop;
b59f45d0 HX	73
13996378	74	if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) {
1da177e4 LT	75	decaps = 1;
	76	break;
	77	}
	78
	79	if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) < 0)
	80	goto drop;
	81	} while (!err);
	82
	83	/* Allocate new secpath or COW existing one. */
	84	if (!skb->sp \|\| atomic_read(&skb->sp->refcnt) != 1) {
	85	struct sec_path *sp;
	86	sp = secpath_dup(skb->sp);
	87	if (!sp)
	88	goto drop;
	89	if (skb->sp)
	90	secpath_put(skb->sp);
	91	skb->sp = sp;
	92	}
	93
	94	if (xfrm_nr + skb->sp->len > XFRM_MAX_DEPTH)
	95	goto drop;
	96
dbe5b4aa HX	97	memcpy(skb->sp->xvec + skb->sp->len, xfrm_vec,
dbe5b4aa HX	98	xfrm_nr * sizeof(xfrm_vec[0]));
1da177e4	99	skb->sp->len += xfrm_nr;
1da177e4	100
b05e1066 PM	101	nf_reset(skb);
b05e1066 PM	102
1da177e4	103	if (decaps) {
f282d45c KM	104	dst_release(skb->dst);
f282d45c KM	105	skb->dst = NULL;
1da177e4 LT	106	netif_rx(skb);
	107	return -1;
	108	} else {
b05e1066	109	#ifdef CONFIG_NETFILTER
0660e03f	110	ipv6_hdr(skb)->payload_len = htons(skb->len);
d56f90a7	111	__skb_push(skb, skb->data - skb_network_header(skb));
b05e1066 PM	112
b05e1066 PM	113	NF_HOOK(PF_INET6, NF_IP6_PRE_ROUTING, skb, skb->dev, NULL,
1ab1457c	114	ip6_rcv_finish);
b05e1066 PM	115	return -1;
b05e1066 PM	116	#else
1da177e4	117	return 1;
b05e1066	118	#endif
1da177e4 LT	119	}
	120
	121	drop_unlock:
	122	spin_unlock(&x->lock);
	123	xfrm_state_put(x);
	124	drop:
	125	while (--xfrm_nr >= 0)
dbe5b4aa	126	xfrm_state_put(xfrm_vec[xfrm_nr]);
1da177e4 LT	127	kfree_skb(skb);
	128	return -1;
	129	}
	130
	131	EXPORT_SYMBOL(xfrm6_rcv_spi);
	132
e5bbef20	133	int xfrm6_rcv(struct sk_buff *skb)
1da177e4	134	{
33b5ecb8 HX	135	return xfrm6_rcv_spi(skb, skb_network_header(skb)[IP6CB(skb)->nhoff],
33b5ecb8 HX	136	0);
1da177e4	137	}
fbd9a5b4	138
7159039a YH	139	EXPORT_SYMBOL(xfrm6_rcv);
7159039a YH	140
fbd9a5b4 MN	141	int xfrm6_input_addr(struct sk_buff skb, xfrm_address_t daddr,
	142	xfrm_address_t *saddr, u8 proto)
	143	{
1ab1457c YH	144	struct xfrm_state *x = NULL;
1ab1457c YH	145	int wildcard = 0;
fbd9a5b4 MN	146	xfrm_address_t *xany;
fbd9a5b4 MN	147	struct xfrm_state *xfrm_vec_one = NULL;
1ab1457c	148	int nh = 0;
fbd9a5b4 MN	149	int i = 0;
fbd9a5b4 MN	150
c53b3590	151	xany = (xfrm_address_t *)&in6addr_any;
fbd9a5b4 MN	152
	153	for (i = 0; i < 3; i++) {
	154	xfrm_address_t dst, src;
	155	switch (i) {
	156	case 0:
	157	dst = daddr;
	158	src = saddr;
	159	break;
	160	case 1:
	161	/* lookup state with wild-card source address */
	162	wildcard = 1;
	163	dst = daddr;
	164	src = xany;
	165	break;
	166	case 2:
	167	default:
1ab1457c	168	/* lookup state with wild-card addresses */
fbd9a5b4 MN	169	wildcard = 1; /* XXX */
	170	dst = xany;
	171	src = xany;
	172	break;
1ab1457c	173	}
fbd9a5b4 MN	174
	175	x = xfrm_state_lookup_byaddr(dst, src, proto, AF_INET6);
	176	if (!x)
	177	continue;
	178
	179	spin_lock(&x->lock);
	180
	181	if (wildcard) {
	182	if ((x->props.flags & XFRM_STATE_WILDRECV) == 0) {
	183	spin_unlock(&x->lock);
	184	xfrm_state_put(x);
	185	x = NULL;
	186	continue;
	187	}
	188	}
	189
	190	if (unlikely(x->km.state != XFRM_STATE_VALID)) {
	191	spin_unlock(&x->lock);
	192	xfrm_state_put(x);
1ab1457c YH	193	x = NULL;
1ab1457c YH	194	continue;
fbd9a5b4 MN	195	}
	196	if (xfrm_state_check_expire(x)) {
	197	spin_unlock(&x->lock);
	198	xfrm_state_put(x);
	199	x = NULL;
	200	continue;
	201	}
	202
	203	nh = x->type->input(x, skb);
	204	if (nh <= 0) {
	205	spin_unlock(&x->lock);
	206	xfrm_state_put(x);
	207	x = NULL;
	208	continue;
	209	}
	210
	211	x->curlft.bytes += skb->len;
	212	x->curlft.packets++;
	213
	214	spin_unlock(&x->lock);
	215
	216	xfrm_vec_one = x;
	217	break;
	218	}
	219
	220	if (!xfrm_vec_one)
	221	goto drop;
	222
	223	/* Allocate new secpath or COW existing one. */
	224	if (!skb->sp \|\| atomic_read(&skb->sp->refcnt) != 1) {
	225	struct sec_path *sp;
	226	sp = secpath_dup(skb->sp);
	227	if (!sp)
	228	goto drop;
	229	if (skb->sp)
	230	secpath_put(skb->sp);
	231	skb->sp = sp;
	232	}
	233
	234	if (1 + skb->sp->len > XFRM_MAX_DEPTH)
	235	goto drop;
	236
	237	skb->sp->xvec[skb->sp->len] = xfrm_vec_one;
	238	skb->sp->len ++;
	239
	240	return 1;
	241	drop:
	242	if (xfrm_vec_one)
	243	xfrm_state_put(xfrm_vec_one);
	244	return -1;
	245	}
7159039a YH	246
7159039a YH	247	EXPORT_SYMBOL(xfrm6_input_addr);