[net-next-2.6.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>

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) {
		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(skb);
		if (err)
			goto error;

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

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

		spin_unlock_bh(&x->lock);

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

	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>
	5	*
	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
1da177e4 LT	20	static int xfrm6_tunnel_check_size(struct sk_buff *skb)
	21	{
	22	int mtu, ret = 0;
	23	struct dst_entry *dst = skb->dst;
	24
	25	mtu = dst_mtu(dst);
	26	if (mtu < IPV6_MIN_MTU)
	27	mtu = IPV6_MIN_MTU;
	28
	29	if (skb->len > mtu) {
180e4250	30	skb->dev = dst->dev;
1da177e4 LT	31	icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
	32	ret = -EMSGSIZE;
	33	}
	34
	35	return ret;
	36	}
	37
16a6677f	38	static int xfrm6_output_one(struct sk_buff *skb)
1da177e4 LT	39	{
	40	struct dst_entry *dst = skb->dst;
	41	struct xfrm_state *x = dst->xfrm;
	42	int err;
	43
84fa7933 PM	44	if (skb->ip_summed == CHECKSUM_PARTIAL) {
84fa7933 PM	45	err = skb_checksum_help(skb);
1da177e4 LT	46	if (err)
	47	goto error_nolock;
	48	}
	49
	50	if (x->props.mode) {
	51	err = xfrm6_tunnel_check_size(skb);
	52	if (err)
	53	goto error_nolock;
	54	}
	55
16a6677f PM	56	do {
	57	spin_lock_bh(&x->lock);
	58	err = xfrm_state_check(x, skb);
	59	if (err)
	60	goto error;
1da177e4	61
b59f45d0 HX	62	err = x->mode->output(skb);
	63	if (err)
	64	goto error;
1da177e4	65
16a6677f PM	66	err = x->type->output(x, skb);
	67	if (err)
	68	goto error;
1da177e4	69
16a6677f PM	70	x->curlft.bytes += skb->len;
16a6677f PM	71	x->curlft.packets++;
1da177e4	72
16a6677f	73	spin_unlock_bh(&x->lock);
1da177e4	74
16a6677f PM	75	skb->nh.raw = skb->data;
	76
	77	if (!(skb->dst = dst_pop(dst))) {
	78	err = -EHOSTUNREACH;
	79	goto error_nolock;
	80	}
	81	dst = skb->dst;
	82	x = dst->xfrm;
	83	} while (x && !x->props.mode);
	84
3e3850e9	85	IP6CB(skb)->flags \|= IP6SKB_XFRM_TRANSFORMED;
16a6677f	86	err = 0;
1da177e4 LT	87
	88	out_exit:
	89	return err;
	90	error:
	91	spin_unlock_bh(&x->lock);
	92	error_nolock:
	93	kfree_skb(skb);
	94	goto out_exit;
	95	}
16a6677f	96
09b8f7a9	97	static int xfrm6_output_finish2(struct sk_buff *skb)
16a6677f PM	98	{
	99	int err;
	100
	101	while (likely((err = xfrm6_output_one(skb)) == 0)) {
	102	nf_reset(skb);
	103
	104	err = nf_hook(PF_INET6, NF_IP6_LOCAL_OUT, &skb, NULL,
	105	skb->dst->dev, dst_output);
	106	if (unlikely(err != 1))
	107	break;
	108
	109	if (!skb->dst->xfrm)
	110	return dst_output(skb);
	111
	112	err = nf_hook(PF_INET6, NF_IP6_POST_ROUTING, &skb, NULL,
09b8f7a9	113	skb->dst->dev, xfrm6_output_finish2);
16a6677f PM	114	if (unlikely(err != 1))
	115	break;
	116	}
	117
	118	return err;
	119	}
	120
09b8f7a9 HX	121	static int xfrm6_output_finish(struct sk_buff *skb)
	122	{
	123	struct sk_buff *segs;
	124
89114afd	125	if (!skb_is_gso(skb))
09b8f7a9 HX	126	return xfrm6_output_finish2(skb);
09b8f7a9 HX	127
679e898a	128	skb->protocol = htons(ETH_P_IPV6);
09b8f7a9 HX	129	segs = skb_gso_segment(skb, 0);
	130	kfree_skb(skb);
	131	if (unlikely(IS_ERR(segs)))
	132	return PTR_ERR(segs);
	133
	134	do {
	135	struct sk_buff *nskb = segs->next;
	136	int err;
	137
	138	segs->next = NULL;
	139	err = xfrm6_output_finish2(segs);
	140
	141	if (unlikely(err)) {
	142	while ((segs = nskb)) {
	143	nskb = segs->next;
	144	segs->next = NULL;
	145	kfree_skb(segs);
	146	}
	147	return err;
	148	}
	149
	150	segs = nskb;
	151	} while (segs);
	152
	153	return 0;
	154	}
	155
16a6677f PM	156	int xfrm6_output(struct sk_buff *skb)
	157	{
	158	return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb, NULL, skb->dst->dev,
	159	xfrm6_output_finish);
	160	}