[deliverable/linux.git] / net / ipv6 / xfrm6_output.c

/*
 * xfrm6_output.c - Common IPsec encapsulation code for IPv6.
 * Copyright (C) 2002 USAGI/WIDE Project
 * Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/compiler.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/icmpv6.h>
#include <linux/netfilter_ipv6.h>
#include <net/ipv6.h>
#include <net/xfrm.h>

int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
			  u8 **prevhdr)
{
	return ip6_find_1stfragopt(skb, prevhdr);
}

EXPORT_SYMBOL(xfrm6_find_1stfragopt);

static int xfrm6_tunnel_check_size(struct sk_buff *skb)
{
	int mtu, ret = 0;
	struct dst_entry *dst = skb->dst;

	mtu = dst_mtu(dst);
	if (mtu < IPV6_MIN_MTU)
		mtu = IPV6_MIN_MTU;

	if (skb->len > mtu) {
		skb->dev = dst->dev;
		icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
		ret = -EMSGSIZE;
	}

	return ret;
}

static int xfrm6_output_one(struct sk_buff *skb)
{
	struct dst_entry *dst = skb->dst;
	struct xfrm_state *x = dst->xfrm;
	int err;

	if (skb->ip_summed == CHECKSUM_PARTIAL) {
		err = skb_checksum_help(skb);
		if (err)
			goto error_nolock;
	}

	if (x->props.mode == XFRM_MODE_TUNNEL) {
		err = xfrm6_tunnel_check_size(skb);
		if (err)
			goto error_nolock;
	}

	do {
		spin_lock_bh(&x->lock);
		err = xfrm_state_check(x, skb);
		if (err)
			goto error;

		err = x->mode->output(x, skb);
		if (err)
			goto error;

		err = x->type->output(x, skb);
		if (err)
			goto error;

		x->curlft.bytes += skb->len;
		x->curlft.packets++;
		if (x->props.mode == XFRM_MODE_ROUTEOPTIMIZATION)
			x->lastused = get_seconds();

		spin_unlock_bh(&x->lock);

		skb_reset_network_header(skb);

		if (!(skb->dst = dst_pop(dst))) {
			err = -EHOSTUNREACH;
			goto error_nolock;
		}
		dst = skb->dst;
		x = dst->xfrm;
	} while (x && (x->props.mode != XFRM_MODE_TUNNEL));

	IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
	err = 0;

out_exit:
	return err;
error:
	spin_unlock_bh(&x->lock);
error_nolock:
	kfree_skb(skb);
	goto out_exit;
}

static int xfrm6_output_finish2(struct sk_buff *skb)
{
	int err;

	while (likely((err = xfrm6_output_one(skb)) == 0)) {
		nf_reset(skb);

		err = nf_hook(PF_INET6, NF_IP6_LOCAL_OUT, &skb, NULL,
			      skb->dst->dev, dst_output);
		if (unlikely(err != 1))
			break;

		if (!skb->dst->xfrm)
			return dst_output(skb);

		err = nf_hook(PF_INET6, NF_IP6_POST_ROUTING, &skb, NULL,
			      skb->dst->dev, xfrm6_output_finish2);
		if (unlikely(err != 1))
			break;
	}

	return err;
}

static int xfrm6_output_finish(struct sk_buff *skb)
{
	struct sk_buff *segs;

	if (!skb_is_gso(skb))
		return xfrm6_output_finish2(skb);

	skb->protocol = htons(ETH_P_IPV6);
	segs = skb_gso_segment(skb, 0);
	kfree_skb(skb);
	if (unlikely(IS_ERR(segs)))
		return PTR_ERR(segs);

	do {
		struct sk_buff *nskb = segs->next;
		int err;

		segs->next = NULL;
		err = xfrm6_output_finish2(segs);

		if (unlikely(err)) {
			while ((segs = nskb)) {
				nskb = segs->next;
				segs->next = NULL;
				kfree_skb(segs);
			}
			return err;
		}

		segs = nskb;
	} while (segs);

	return 0;
}

int xfrm6_output(struct sk_buff *skb)
{
	return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb, NULL, skb->dst->dev,
		       xfrm6_output_finish);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* xfrm6_output.c - Common IPsec encapsulation code for IPv6.
	3	* Copyright (C) 2002 USAGI/WIDE Project
	4	* Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
1ab1457c	5	*
1da177e4 LT	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*/
	11
16a6677f	12	#include <linux/compiler.h>
1da177e4 LT	13	#include <linux/skbuff.h>
	14	#include <linux/spinlock.h>
	15	#include <linux/icmpv6.h>
16a6677f	16	#include <linux/netfilter_ipv6.h>
1da177e4 LT	17	#include <net/ipv6.h>
	18	#include <net/xfrm.h>
	19
aee5adb4 MN	20	int xfrm6_find_1stfragopt(struct xfrm_state x, struct sk_buff skb,
	21	u8 **prevhdr)
	22	{
	23	return ip6_find_1stfragopt(skb, prevhdr);
	24	}
	25
7159039a YH	26	EXPORT_SYMBOL(xfrm6_find_1stfragopt);
7159039a YH	27
1da177e4 LT	28	static int xfrm6_tunnel_check_size(struct sk_buff *skb)
	29	{
	30	int mtu, ret = 0;
	31	struct dst_entry *dst = skb->dst;
	32
	33	mtu = dst_mtu(dst);
	34	if (mtu < IPV6_MIN_MTU)
	35	mtu = IPV6_MIN_MTU;
	36
	37	if (skb->len > mtu) {
180e4250	38	skb->dev = dst->dev;
1da177e4 LT	39	icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
	40	ret = -EMSGSIZE;
	41	}
	42
	43	return ret;
	44	}
	45
16a6677f	46	static int xfrm6_output_one(struct sk_buff *skb)
1da177e4 LT	47	{
	48	struct dst_entry *dst = skb->dst;
	49	struct xfrm_state *x = dst->xfrm;
	50	int err;
1ab1457c	51
84fa7933 PM	52	if (skb->ip_summed == CHECKSUM_PARTIAL) {
84fa7933 PM	53	err = skb_checksum_help(skb);
1da177e4 LT	54	if (err)
	55	goto error_nolock;
	56	}
	57
7e49e6de	58	if (x->props.mode == XFRM_MODE_TUNNEL) {
1da177e4 LT	59	err = xfrm6_tunnel_check_size(skb);
	60	if (err)
	61	goto error_nolock;
	62	}
	63
16a6677f PM	64	do {
	65	spin_lock_bh(&x->lock);
	66	err = xfrm_state_check(x, skb);
	67	if (err)
	68	goto error;
1da177e4	69
eb878e84	70	err = x->mode->output(x, skb);
b59f45d0 HX	71	if (err)
b59f45d0 HX	72	goto error;
1da177e4	73
16a6677f PM	74	err = x->type->output(x, skb);
	75	if (err)
	76	goto error;
1da177e4	77
16a6677f PM	78	x->curlft.bytes += skb->len;
16a6677f PM	79	x->curlft.packets++;
9afaca05	80	if (x->props.mode == XFRM_MODE_ROUTEOPTIMIZATION)
9d729f72	81	x->lastused = get_seconds();
1da177e4	82
16a6677f	83	spin_unlock_bh(&x->lock);
1da177e4	84
c1d2bbe1	85	skb_reset_network_header(skb);
1ab1457c	86
16a6677f PM	87	if (!(skb->dst = dst_pop(dst))) {
	88	err = -EHOSTUNREACH;
	89	goto error_nolock;
	90	}
	91	dst = skb->dst;
	92	x = dst->xfrm;
7e49e6de	93	} while (x && (x->props.mode != XFRM_MODE_TUNNEL));
16a6677f	94
3e3850e9	95	IP6CB(skb)->flags \|= IP6SKB_XFRM_TRANSFORMED;
16a6677f	96	err = 0;
1da177e4 LT	97
	98	out_exit:
	99	return err;
	100	error:
	101	spin_unlock_bh(&x->lock);
	102	error_nolock:
	103	kfree_skb(skb);
	104	goto out_exit;
	105	}
16a6677f	106
09b8f7a9	107	static int xfrm6_output_finish2(struct sk_buff *skb)
16a6677f PM	108	{
	109	int err;
	110
	111	while (likely((err = xfrm6_output_one(skb)) == 0)) {
	112	nf_reset(skb);
1ab1457c	113
16a6677f PM	114	err = nf_hook(PF_INET6, NF_IP6_LOCAL_OUT, &skb, NULL,
	115	skb->dst->dev, dst_output);
	116	if (unlikely(err != 1))
	117	break;
	118
	119	if (!skb->dst->xfrm)
	120	return dst_output(skb);
	121
	122	err = nf_hook(PF_INET6, NF_IP6_POST_ROUTING, &skb, NULL,
09b8f7a9	123	skb->dst->dev, xfrm6_output_finish2);
16a6677f PM	124	if (unlikely(err != 1))
	125	break;
	126	}
	127
	128	return err;
	129	}
	130
09b8f7a9 HX	131	static int xfrm6_output_finish(struct sk_buff *skb)
	132	{
	133	struct sk_buff *segs;
	134
89114afd	135	if (!skb_is_gso(skb))
09b8f7a9 HX	136	return xfrm6_output_finish2(skb);
09b8f7a9 HX	137
679e898a	138	skb->protocol = htons(ETH_P_IPV6);
09b8f7a9 HX	139	segs = skb_gso_segment(skb, 0);
	140	kfree_skb(skb);
	141	if (unlikely(IS_ERR(segs)))
	142	return PTR_ERR(segs);
	143
	144	do {
	145	struct sk_buff *nskb = segs->next;
	146	int err;
	147
	148	segs->next = NULL;
	149	err = xfrm6_output_finish2(segs);
	150
	151	if (unlikely(err)) {
	152	while ((segs = nskb)) {
	153	nskb = segs->next;
	154	segs->next = NULL;
	155	kfree_skb(segs);
	156	}
	157	return err;
	158	}
	159
	160	segs = nskb;
	161	} while (segs);
	162
	163	return 0;
	164	}
	165
16a6677f PM	166	int xfrm6_output(struct sk_buff *skb)
	167	{
	168	return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb, NULL, skb->dst->dev,
	169	xfrm6_output_finish);
	170	}