[net-next-2.6.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, __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;
	int nexthdr;
	unsigned int nhoff;

	nhoff = IP6CB(skb)->nhoff;
	nexthdr = skb->nh.raw[nhoff];

	seq = 0;
	if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0)
		goto drop;
	
	do {
		struct ipv6hdr *iph = skb->nh.ipv6h;

		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->nh.raw[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->mode->input(x, skb))
			goto drop;

		if (x->props.mode == XFRM_MODE_TUNNEL) { /* XXX */
			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;
	skb->ip_summed = CHECKSUM_NONE;

	nf_reset(skb);

	if (decaps) {
		if (!(skb->dev->flags&IFF_LOOPBACK)) {
			dst_release(skb->dst);
			skb->dst = NULL;
		}
		netif_rx(skb);
		return -1;
	} else {
#ifdef CONFIG_NETFILTER
		skb->nh.ipv6h->payload_len = htons(skb->len);
		__skb_push(skb, skb->data - skb->nh.raw);

		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 **pskb)
{
	return xfrm6_rcv_spi(*pskb, 0);
}

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;
	struct in6_addr any;
	xfrm_address_t *xany;
	struct xfrm_state *xfrm_vec_one = NULL;
 	int nh = 0;
	int i = 0;

	ipv6_addr_set(&any, 0, 0, 0, 0);
	xany = (xfrm_address_t *)&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;
}
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
a252cc23	19	int xfrm6_rcv_spi(struct sk_buff *skb, __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;
	27	int nexthdr;
	28	unsigned int nhoff;
	29
951dbc8a	30	nhoff = IP6CB(skb)->nhoff;
1da177e4 LT	31	nexthdr = skb->nh.raw[nhoff];
	32
	33	seq = 0;
	34	if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0)
	35	goto drop;
	36
	37	do {
	38	struct ipv6hdr *iph = skb->nh.ipv6h;
	39
	40	if (xfrm_nr == XFRM_MAX_DEPTH)
	41	goto drop;
	42
	43	x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi, nexthdr, AF_INET6);
	44	if (x == NULL)
	45	goto drop;
	46	spin_lock(&x->lock);
	47	if (unlikely(x->km.state != XFRM_STATE_VALID))
	48	goto drop_unlock;
	49
	50	if (x->props.replay_window && xfrm_replay_check(x, seq))
	51	goto drop_unlock;
	52
	53	if (xfrm_state_check_expire(x))
	54	goto drop_unlock;
	55
e695633e	56	nexthdr = x->type->input(x, skb);
1da177e4 LT	57	if (nexthdr <= 0)
	58	goto drop_unlock;
	59
	60	skb->nh.raw[nhoff] = nexthdr;
	61
	62	if (x->props.replay_window)
	63	xfrm_replay_advance(x, seq);
	64
	65	x->curlft.bytes += skb->len;
	66	x->curlft.packets++;
	67
	68	spin_unlock(&x->lock);
	69
dbe5b4aa	70	xfrm_vec[xfrm_nr++] = x;
1da177e4	71
b59f45d0 HX	72	if (x->mode->input(x, skb))
	73	goto drop;
	74
7e49e6de	75	if (x->props.mode == XFRM_MODE_TUNNEL) { /* XXX */
1da177e4 LT	76	decaps = 1;
	77	break;
	78	}
	79
	80	if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) < 0)
	81	goto drop;
	82	} while (!err);
	83
	84	/* Allocate new secpath or COW existing one. */
	85	if (!skb->sp \|\| atomic_read(&skb->sp->refcnt) != 1) {
	86	struct sec_path *sp;
	87	sp = secpath_dup(skb->sp);
	88	if (!sp)
	89	goto drop;
	90	if (skb->sp)
	91	secpath_put(skb->sp);
	92	skb->sp = sp;
	93	}
	94
	95	if (xfrm_nr + skb->sp->len > XFRM_MAX_DEPTH)
	96	goto drop;
	97
dbe5b4aa HX	98	memcpy(skb->sp->xvec + skb->sp->len, xfrm_vec,
dbe5b4aa HX	99	xfrm_nr * sizeof(xfrm_vec[0]));
1da177e4 LT	100	skb->sp->len += xfrm_nr;
	101	skb->ip_summed = CHECKSUM_NONE;
	102
b05e1066 PM	103	nf_reset(skb);
b05e1066 PM	104
1da177e4 LT	105	if (decaps) {
	106	if (!(skb->dev->flags&IFF_LOOPBACK)) {
	107	dst_release(skb->dst);
	108	skb->dst = NULL;
	109	}
	110	netif_rx(skb);
	111	return -1;
	112	} else {
b05e1066 PM	113	#ifdef CONFIG_NETFILTER
	114	skb->nh.ipv6h->payload_len = htons(skb->len);
	115	__skb_push(skb, skb->data - skb->nh.raw);
	116
	117	NF_HOOK(PF_INET6, NF_IP6_PRE_ROUTING, skb, skb->dev, NULL,
	118	ip6_rcv_finish);
	119	return -1;
	120	#else
1da177e4	121	return 1;
b05e1066	122	#endif
1da177e4 LT	123	}
	124
	125	drop_unlock:
	126	spin_unlock(&x->lock);
	127	xfrm_state_put(x);
	128	drop:
	129	while (--xfrm_nr >= 0)
dbe5b4aa	130	xfrm_state_put(xfrm_vec[xfrm_nr]);
1da177e4 LT	131	kfree_skb(skb);
	132	return -1;
	133	}
	134
	135	EXPORT_SYMBOL(xfrm6_rcv_spi);
	136
951dbc8a	137	int xfrm6_rcv(struct sk_buff **pskb)
1da177e4	138	{
d2acc347	139	return xfrm6_rcv_spi(*pskb, 0);
1da177e4	140	}
fbd9a5b4 MN	141
	142	int xfrm6_input_addr(struct sk_buff skb, xfrm_address_t daddr,
	143	xfrm_address_t *saddr, u8 proto)
	144	{
	145	struct xfrm_state *x = NULL;
	146	int wildcard = 0;
	147	struct in6_addr any;
	148	xfrm_address_t *xany;
	149	struct xfrm_state *xfrm_vec_one = NULL;
	150	int nh = 0;
	151	int i = 0;
	152
	153	ipv6_addr_set(&any, 0, 0, 0, 0);
	154	xany = (xfrm_address_t *)&any;
	155
	156	for (i = 0; i < 3; i++) {
	157	xfrm_address_t dst, src;
	158	switch (i) {
	159	case 0:
	160	dst = daddr;
	161	src = saddr;
	162	break;
	163	case 1:
	164	/* lookup state with wild-card source address */
	165	wildcard = 1;
	166	dst = daddr;
	167	src = xany;
	168	break;
	169	case 2:
	170	default:
	171	/* lookup state with wild-card addresses */
	172	wildcard = 1; /* XXX */
	173	dst = xany;
	174	src = xany;
	175	break;
	176	}
	177
	178	x = xfrm_state_lookup_byaddr(dst, src, proto, AF_INET6);
	179	if (!x)
	180	continue;
	181
	182	spin_lock(&x->lock);
	183
	184	if (wildcard) {
	185	if ((x->props.flags & XFRM_STATE_WILDRECV) == 0) {
	186	spin_unlock(&x->lock);
	187	xfrm_state_put(x);
	188	x = NULL;
	189	continue;
	190	}
	191	}
	192
	193	if (unlikely(x->km.state != XFRM_STATE_VALID)) {
	194	spin_unlock(&x->lock);
	195	xfrm_state_put(x);
	196	x = NULL;
	197	continue;
	198	}
	199	if (xfrm_state_check_expire(x)) {
	200	spin_unlock(&x->lock);
	201	xfrm_state_put(x);
	202	x = NULL;
	203	continue;
	204	}
205
206	nh = x->type->input(x, skb);
207	if (nh <= 0) {
208	spin_unlock(&x->lock);
209	xfrm_state_put(x);
210	x = NULL;
211	continue;
212	}
213
214	x->curlft.bytes += skb->len;
215	x->curlft.packets++;
216
217	spin_unlock(&x->lock);
218
219	xfrm_vec_one = x;
220	break;
221	}
222
223	if (!xfrm_vec_one)
224	goto drop;
225
226	/* Allocate new secpath or COW existing one. */
227	if (!skb->sp \|\| atomic_read(&skb->sp->refcnt) != 1) {
228	struct sec_path *sp;
229	sp = secpath_dup(skb->sp);
230	if (!sp)
231	goto drop;
232	if (skb->sp)
233	secpath_put(skb->sp);
234	skb->sp = sp;
235	}
236
237	if (1 + skb->sp->len > XFRM_MAX_DEPTH)
238	goto drop;
239
240	skb->sp->xvec[skb->sp->len] = xfrm_vec_one;
241	skb->sp->len ++;
242
243	return 1;
244	drop:
245	if (xfrm_vec_one)
246	xfrm_state_put(xfrm_vec_one);
247	return -1;
248	}