[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);
}

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 = (u64)xtime.tv_sec;

		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 != 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>
	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
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
1da177e4 LT	26	static int xfrm6_tunnel_check_size(struct sk_buff *skb)
	27	{
	28	int mtu, ret = 0;
	29	struct dst_entry *dst = skb->dst;
	30
	31	mtu = dst_mtu(dst);
	32	if (mtu < IPV6_MIN_MTU)
	33	mtu = IPV6_MIN_MTU;
	34
	35	if (skb->len > mtu) {
180e4250	36	skb->dev = dst->dev;
1da177e4 LT	37	icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
	38	ret = -EMSGSIZE;
	39	}
	40
	41	return ret;
	42	}
	43
16a6677f	44	static int xfrm6_output_one(struct sk_buff *skb)
1da177e4 LT	45	{
	46	struct dst_entry *dst = skb->dst;
	47	struct xfrm_state *x = dst->xfrm;
	48	int err;
	49
84fa7933 PM	50	if (skb->ip_summed == CHECKSUM_PARTIAL) {
84fa7933 PM	51	err = skb_checksum_help(skb);
1da177e4 LT	52	if (err)
	53	goto error_nolock;
	54	}
	55
7e49e6de	56	if (x->props.mode == XFRM_MODE_TUNNEL) {
1da177e4 LT	57	err = xfrm6_tunnel_check_size(skb);
	58	if (err)
	59	goto error_nolock;
	60	}
	61
16a6677f PM	62	do {
	63	spin_lock_bh(&x->lock);
	64	err = xfrm_state_check(x, skb);
	65	if (err)
	66	goto error;
1da177e4	67
eb878e84	68	err = x->mode->output(x, skb);
b59f45d0 HX	69	if (err)
b59f45d0 HX	70	goto error;
1da177e4	71
16a6677f PM	72	err = x->type->output(x, skb);
	73	if (err)
	74	goto error;
1da177e4	75
16a6677f PM	76	x->curlft.bytes += skb->len;
16a6677f PM	77	x->curlft.packets++;
9afaca05 MN	78	if (x->props.mode == XFRM_MODE_ROUTEOPTIMIZATION)
9afaca05 MN	79	x->lastused = (u64)xtime.tv_sec;
1da177e4	80
16a6677f	81	spin_unlock_bh(&x->lock);
1da177e4	82
16a6677f PM	83	skb->nh.raw = skb->data;
	84
	85	if (!(skb->dst = dst_pop(dst))) {
	86	err = -EHOSTUNREACH;
	87	goto error_nolock;
	88	}
	89	dst = skb->dst;
	90	x = dst->xfrm;
7e49e6de	91	} while (x && (x->props.mode != XFRM_MODE_TUNNEL));
16a6677f	92
3e3850e9	93	IP6CB(skb)->flags \|= IP6SKB_XFRM_TRANSFORMED;
16a6677f	94	err = 0;
1da177e4 LT	95
	96	out_exit:
	97	return err;
	98	error:
	99	spin_unlock_bh(&x->lock);
	100	error_nolock:
	101	kfree_skb(skb);
	102	goto out_exit;
	103	}
16a6677f	104
09b8f7a9	105	static int xfrm6_output_finish2(struct sk_buff *skb)
16a6677f PM	106	{
	107	int err;
	108
	109	while (likely((err = xfrm6_output_one(skb)) == 0)) {
	110	nf_reset(skb);
	111
	112	err = nf_hook(PF_INET6, NF_IP6_LOCAL_OUT, &skb, NULL,
	113	skb->dst->dev, dst_output);
	114	if (unlikely(err != 1))
	115	break;
	116
	117	if (!skb->dst->xfrm)
	118	return dst_output(skb);
	119
	120	err = nf_hook(PF_INET6, NF_IP6_POST_ROUTING, &skb, NULL,
09b8f7a9	121	skb->dst->dev, xfrm6_output_finish2);
16a6677f PM	122	if (unlikely(err != 1))
	123	break;
	124	}
	125
	126	return err;
	127	}
	128
09b8f7a9 HX	129	static int xfrm6_output_finish(struct sk_buff *skb)
	130	{
	131	struct sk_buff *segs;
	132
89114afd	133	if (!skb_is_gso(skb))
09b8f7a9 HX	134	return xfrm6_output_finish2(skb);
09b8f7a9 HX	135
679e898a	136	skb->protocol = htons(ETH_P_IPV6);
09b8f7a9 HX	137	segs = skb_gso_segment(skb, 0);
	138	kfree_skb(skb);
	139	if (unlikely(IS_ERR(segs)))
	140	return PTR_ERR(segs);
	141
	142	do {
	143	struct sk_buff *nskb = segs->next;
	144	int err;
	145
	146	segs->next = NULL;
	147	err = xfrm6_output_finish2(segs);
	148
	149	if (unlikely(err)) {
	150	while ((segs = nskb)) {
	151	nskb = segs->next;
	152	segs->next = NULL;
	153	kfree_skb(segs);
	154	}
	155	return err;
	156	}
	157
	158	segs = nskb;
	159	} while (segs);
	160
	161	return 0;
	162	}
	163
16a6677f PM	164	int xfrm6_output(struct sk_buff *skb)
	165	{
	166	return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb, NULL, skb->dst->dev,
	167	xfrm6_output_finish);
	168	}