[linux.git] / net / ipv6 / esp6.c

/*
 * Copyright (C)2002 USAGI/WIDE Project
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Authors
 *
 *	Mitsuru KANDA @USAGI       : IPv6 Support
 * 	Kazunori MIYAZAWA @USAGI   :
 * 	Kunihiro Ishiguro <[email protected]>
 *
 * 	This file is derived from net/ipv4/esp.c
 */

#include <crypto/aead.h>
#include <crypto/authenc.h>
#include <linux/err.h>
#include <linux/module.h>
#include <net/ip.h>
#include <net/xfrm.h>
#include <net/esp.h>
#include <linux/scatterlist.h>
#include <linux/kernel.h>
#include <linux/pfkeyv2.h>
#include <linux/random.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <net/icmp.h>
#include <net/ipv6.h>
#include <net/protocol.h>
#include <linux/icmpv6.h>

struct esp_skb_cb {
	struct xfrm_skb_cb xfrm;
	void *tmp;
};

#define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0]))

static u32 esp6_get_mtu(struct xfrm_state *x, int mtu);

/*
 * Allocate an AEAD request structure with extra space for SG and IV.
 *
 * For alignment considerations the upper 32 bits of the sequence number are
 * placed at the front, if present. Followed by the IV, the request and finally
 * the SG list.
 *
 * TODO: Use spare space in skb for this where possible.
 */
static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqihlen)
{
	unsigned int len;

	len = seqihlen;

	len += crypto_aead_ivsize(aead);

	if (len) {
		len += crypto_aead_alignmask(aead) &
		       ~(crypto_tfm_ctx_alignment() - 1);
		len = ALIGN(len, crypto_tfm_ctx_alignment());
	}

	len += sizeof(struct aead_givcrypt_request) + crypto_aead_reqsize(aead);
	len = ALIGN(len, __alignof__(struct scatterlist));

	len += sizeof(struct scatterlist) * nfrags;

	return kmalloc(len, GFP_ATOMIC);
}

static inline __be32 *esp_tmp_seqhi(void *tmp)
{
	return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32));
}

static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen)
{
	return crypto_aead_ivsize(aead) ?
	       PTR_ALIGN((u8 *)tmp + seqhilen,
			 crypto_aead_alignmask(aead) + 1) : tmp + seqhilen;
}

static inline struct aead_givcrypt_request *esp_tmp_givreq(
	struct crypto_aead *aead, u8 *iv)
{
	struct aead_givcrypt_request *req;

	req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead),
				crypto_tfm_ctx_alignment());
	aead_givcrypt_set_tfm(req, aead);
	return req;
}

static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv)
{
	struct aead_request *req;

	req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead),
				crypto_tfm_ctx_alignment());
	aead_request_set_tfm(req, aead);
	return req;
}

static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead,
					     struct aead_request *req)
{
	return (void *)ALIGN((unsigned long)(req + 1) +
			     crypto_aead_reqsize(aead),
			     __alignof__(struct scatterlist));
}

static inline struct scatterlist *esp_givreq_sg(
	struct crypto_aead *aead, struct aead_givcrypt_request *req)
{
	return (void *)ALIGN((unsigned long)(req + 1) +
			     crypto_aead_reqsize(aead),
			     __alignof__(struct scatterlist));
}

static void esp_output_done(struct crypto_async_request *base, int err)
{
	struct sk_buff *skb = base->data;

	kfree(ESP_SKB_CB(skb)->tmp);
	xfrm_output_resume(skb, err);
}

static int esp6_output(struct xfrm_state *x, struct sk_buff *skb)
{
	int err;
	struct ip_esp_hdr *esph;
	struct crypto_aead *aead;
	struct aead_givcrypt_request *req;
	struct scatterlist *sg;
	struct scatterlist *asg;
	struct sk_buff *trailer;
	void *tmp;
	int blksize;
	int clen;
	int alen;
	int plen;
	int tfclen;
	int nfrags;
	int assoclen;
	int sglists;
	int seqhilen;
	u8 *iv;
	u8 *tail;
	__be32 *seqhi;
	struct esp_data *esp = x->data;

	/* skb is pure payload to encrypt */
	err = -ENOMEM;

	aead = esp->aead;
	alen = crypto_aead_authsize(aead);

	tfclen = 0;
	if (x->tfcpad) {
		struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb);
		u32 padto;

		padto = min(x->tfcpad, esp6_get_mtu(x, dst->child_mtu_cached));
		if (skb->len < padto)
			tfclen = padto - skb->len;
	}
	blksize = ALIGN(crypto_aead_blocksize(aead), 4);
	clen = ALIGN(skb->len + 2 + tfclen, blksize);
	if (esp->padlen)
		clen = ALIGN(clen, esp->padlen);
	plen = clen - skb->len - tfclen;

	err = skb_cow_data(skb, tfclen + plen + alen, &trailer);
	if (err < 0)
		goto error;
	nfrags = err;

	assoclen = sizeof(*esph);
	sglists = 1;
	seqhilen = 0;

	if (x->props.flags & XFRM_STATE_ESN) {
		sglists += 2;
		seqhilen += sizeof(__be32);
		assoclen += seqhilen;
	}

	tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen);
	if (!tmp)
		goto error;

	seqhi = esp_tmp_seqhi(tmp);
	iv = esp_tmp_iv(aead, tmp, seqhilen);
	req = esp_tmp_givreq(aead, iv);
	asg = esp_givreq_sg(aead, req);
	sg = asg + sglists;

	/* Fill padding... */
	tail = skb_tail_pointer(trailer);
	if (tfclen) {
		memset(tail, 0, tfclen);
		tail += tfclen;
	}
	do {
		int i;
		for (i = 0; i < plen - 2; i++)
			tail[i] = i + 1;
	} while (0);
	tail[plen - 2] = plen - 2;
	tail[plen - 1] = *skb_mac_header(skb);
	pskb_put(skb, trailer, clen - skb->len + alen);

	skb_push(skb, -skb_network_offset(skb));
	esph = ip_esp_hdr(skb);
	*skb_mac_header(skb) = IPPROTO_ESP;

	esph->spi = x->id.spi;
	esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);

	sg_init_table(sg, nfrags);
	skb_to_sgvec(skb, sg,
		     esph->enc_data + crypto_aead_ivsize(aead) - skb->data,
		     clen + alen);

	if ((x->props.flags & XFRM_STATE_ESN)) {
		sg_init_table(asg, 3);
		sg_set_buf(asg, &esph->spi, sizeof(__be32));
		*seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi);
		sg_set_buf(asg + 1, seqhi, seqhilen);
		sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32));
	} else
		sg_init_one(asg, esph, sizeof(*esph));

	aead_givcrypt_set_callback(req, 0, esp_output_done, skb);
	aead_givcrypt_set_crypt(req, sg, sg, clen, iv);
	aead_givcrypt_set_assoc(req, asg, assoclen);
	aead_givcrypt_set_giv(req, esph->enc_data,
			      XFRM_SKB_CB(skb)->seq.output.low);

	ESP_SKB_CB(skb)->tmp = tmp;
	err = crypto_aead_givencrypt(req);
	if (err == -EINPROGRESS)
		goto error;

	if (err == -EBUSY)
		err = NET_XMIT_DROP;

	kfree(tmp);

error:
	return err;
}

static int esp_input_done2(struct sk_buff *skb, int err)
{
	struct xfrm_state *x = xfrm_input_state(skb);
	struct esp_data *esp = x->data;
	struct crypto_aead *aead = esp->aead;
	int alen = crypto_aead_authsize(aead);
	int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead);
	int elen = skb->len - hlen;
	int hdr_len = skb_network_header_len(skb);
	int padlen;
	u8 nexthdr[2];

	kfree(ESP_SKB_CB(skb)->tmp);

	if (unlikely(err))
		goto out;

	if (skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2))
		BUG();

	err = -EINVAL;
	padlen = nexthdr[0];
	if (padlen + 2 + alen >= elen) {
		LIMIT_NETDEBUG(KERN_WARNING "ipsec esp packet is garbage "
			       "padlen=%d, elen=%d\n", padlen + 2, elen - alen);
		goto out;
	}

	/* ... check padding bits here. Silly. :-) */

	pskb_trim(skb, skb->len - alen - padlen - 2);
	__skb_pull(skb, hlen);
	skb_set_transport_header(skb, -hdr_len);

	err = nexthdr[1];

	/* RFC4303: Drop dummy packets without any error */
	if (err == IPPROTO_NONE)
		err = -EINVAL;

out:
	return err;
}

static void esp_input_done(struct crypto_async_request *base, int err)
{
	struct sk_buff *skb = base->data;

	xfrm_input_resume(skb, esp_input_done2(skb, err));
}

static int esp6_input(struct xfrm_state *x, struct sk_buff *skb)
{
	struct ip_esp_hdr *esph;
	struct esp_data *esp = x->data;
	struct crypto_aead *aead = esp->aead;
	struct aead_request *req;
	struct sk_buff *trailer;
	int elen = skb->len - sizeof(*esph) - crypto_aead_ivsize(aead);
	int nfrags;
	int assoclen;
	int sglists;
	int seqhilen;
	int ret = 0;
	void *tmp;
	__be32 *seqhi;
	u8 *iv;
	struct scatterlist *sg;
	struct scatterlist *asg;

	if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead))) {
		ret = -EINVAL;
		goto out;
	}

	if (elen <= 0) {
		ret = -EINVAL;
		goto out;
	}

	if ((nfrags = skb_cow_data(skb, 0, &trailer)) < 0) {
		ret = -EINVAL;
		goto out;
	}

	ret = -ENOMEM;

	assoclen = sizeof(*esph);
	sglists = 1;
	seqhilen = 0;

	if (x->props.flags & XFRM_STATE_ESN) {
		sglists += 2;
		seqhilen += sizeof(__be32);
		assoclen += seqhilen;
	}

	tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen);
	if (!tmp)
		goto out;

	ESP_SKB_CB(skb)->tmp = tmp;
	seqhi = esp_tmp_seqhi(tmp);
	iv = esp_tmp_iv(aead, tmp, seqhilen);
	req = esp_tmp_req(aead, iv);
	asg = esp_req_sg(aead, req);
	sg = asg + sglists;

	skb->ip_summed = CHECKSUM_NONE;

	esph = (struct ip_esp_hdr *)skb->data;

	/* Get ivec. This can be wrong, check against another impls. */
	iv = esph->enc_data;

	sg_init_table(sg, nfrags);
	skb_to_sgvec(skb, sg, sizeof(*esph) + crypto_aead_ivsize(aead), elen);

	if ((x->props.flags & XFRM_STATE_ESN)) {
		sg_init_table(asg, 3);
		sg_set_buf(asg, &esph->spi, sizeof(__be32));
		*seqhi = XFRM_SKB_CB(skb)->seq.input.hi;
		sg_set_buf(asg + 1, seqhi, seqhilen);
		sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32));
	} else
		sg_init_one(asg, esph, sizeof(*esph));

	aead_request_set_callback(req, 0, esp_input_done, skb);
	aead_request_set_crypt(req, sg, sg, elen, iv);
	aead_request_set_assoc(req, asg, assoclen);

	ret = crypto_aead_decrypt(req);
	if (ret == -EINPROGRESS)
		goto out;

	ret = esp_input_done2(skb, ret);

out:
	return ret;
}

static u32 esp6_get_mtu(struct xfrm_state *x, int mtu)
{
	struct esp_data *esp = x->data;
	u32 blksize = ALIGN(crypto_aead_blocksize(esp->aead), 4);
	u32 align = max_t(u32, blksize, esp->padlen);
	u32 rem;

	mtu -= x->props.header_len + crypto_aead_authsize(esp->aead);
	rem = mtu & (align - 1);
	mtu &= ~(align - 1);

	if (x->props.mode != XFRM_MODE_TUNNEL) {
		u32 padsize = ((blksize - 1) & 7) + 1;
		mtu -= blksize - padsize;
		mtu += min_t(u32, blksize - padsize, rem);
	}

	return mtu - 2;
}

static void esp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
		     u8 type, u8 code, int offset, __be32 info)
{
	struct net *net = dev_net(skb->dev);
	const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
	struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data + offset);
	struct xfrm_state *x;

	if (type != ICMPV6_DEST_UNREACH &&
	    type != ICMPV6_PKT_TOOBIG)
		return;

	x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
			      esph->spi, IPPROTO_ESP, AF_INET6);
	if (!x)
		return;
	printk(KERN_DEBUG "pmtu discovery on SA ESP/%08x/%pI6\n",
			ntohl(esph->spi), &iph->daddr);
	xfrm_state_put(x);
}

static void esp6_destroy(struct xfrm_state *x)
{
	struct esp_data *esp = x->data;

	if (!esp)
		return;

	crypto_free_aead(esp->aead);
	kfree(esp);
}

static int esp_init_aead(struct xfrm_state *x)
{
	struct esp_data *esp = x->data;
	struct crypto_aead *aead;
	int err;

	aead = crypto_alloc_aead(x->aead->alg_name, 0, 0);
	err = PTR_ERR(aead);
	if (IS_ERR(aead))
		goto error;

	esp->aead = aead;

	err = crypto_aead_setkey(aead, x->aead->alg_key,
				 (x->aead->alg_key_len + 7) / 8);
	if (err)
		goto error;

	err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8);
	if (err)
		goto error;

error:
	return err;
}

static int esp_init_authenc(struct xfrm_state *x)
{
	struct esp_data *esp = x->data;
	struct crypto_aead *aead;
	struct crypto_authenc_key_param *param;
	struct rtattr *rta;
	char *key;
	char *p;
	char authenc_name[CRYPTO_MAX_ALG_NAME];
	unsigned int keylen;
	int err;

	err = -EINVAL;
	if (x->ealg == NULL)
		goto error;

	err = -ENAMETOOLONG;

	if ((x->props.flags & XFRM_STATE_ESN)) {
		if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
			     "authencesn(%s,%s)",
			     x->aalg ? x->aalg->alg_name : "digest_null",
			     x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME)
			goto error;
	} else {
		if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
			     "authenc(%s,%s)",
			     x->aalg ? x->aalg->alg_name : "digest_null",
			     x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME)
			goto error;
	}

	aead = crypto_alloc_aead(authenc_name, 0, 0);
	err = PTR_ERR(aead);
	if (IS_ERR(aead))
		goto error;

	esp->aead = aead;

	keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) +
		 (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param));
	err = -ENOMEM;
	key = kmalloc(keylen, GFP_KERNEL);
	if (!key)
		goto error;

	p = key;
	rta = (void *)p;
	rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
	rta->rta_len = RTA_LENGTH(sizeof(*param));
	param = RTA_DATA(rta);
	p += RTA_SPACE(sizeof(*param));

	if (x->aalg) {
		struct xfrm_algo_desc *aalg_desc;

		memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8);
		p += (x->aalg->alg_key_len + 7) / 8;

		aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
		BUG_ON(!aalg_desc);

		err = -EINVAL;
		if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
		    crypto_aead_authsize(aead)) {
			NETDEBUG(KERN_INFO "ESP: %s digestsize %u != %hu\n",
				 x->aalg->alg_name,
				 crypto_aead_authsize(aead),
				 aalg_desc->uinfo.auth.icv_fullbits/8);
			goto free_key;
		}

		err = crypto_aead_setauthsize(
			aead, x->aalg->alg_trunc_len / 8);
		if (err)
			goto free_key;
	}

	param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8);
	memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8);

	err = crypto_aead_setkey(aead, key, keylen);

free_key:
	kfree(key);

error:
	return err;
}

static int esp6_init_state(struct xfrm_state *x)
{
	struct esp_data *esp;
	struct crypto_aead *aead;
	u32 align;
	int err;

	if (x->encap)
		return -EINVAL;

	esp = kzalloc(sizeof(*esp), GFP_KERNEL);
	if (esp == NULL)
		return -ENOMEM;

	x->data = esp;

	if (x->aead)
		err = esp_init_aead(x);
	else
		err = esp_init_authenc(x);

	if (err)
		goto error;

	aead = esp->aead;

	esp->padlen = 0;

	x->props.header_len = sizeof(struct ip_esp_hdr) +
			      crypto_aead_ivsize(aead);
	switch (x->props.mode) {
	case XFRM_MODE_BEET:
		if (x->sel.family != AF_INET6)
			x->props.header_len += IPV4_BEET_PHMAXLEN +
				               (sizeof(struct ipv6hdr) - sizeof(struct iphdr));
		break;
	case XFRM_MODE_TRANSPORT:
		break;
	case XFRM_MODE_TUNNEL:
		x->props.header_len += sizeof(struct ipv6hdr);
		break;
	default:
		goto error;
	}

	align = ALIGN(crypto_aead_blocksize(aead), 4);
	if (esp->padlen)
		align = max_t(u32, align, esp->padlen);
	x->props.trailer_len = align + 1 + crypto_aead_authsize(esp->aead);

error:
	return err;
}

static const struct xfrm_type esp6_type =
{
	.description	= "ESP6",
	.owner	     	= THIS_MODULE,
	.proto	     	= IPPROTO_ESP,
	.flags		= XFRM_TYPE_REPLAY_PROT,
	.init_state	= esp6_init_state,
	.destructor	= esp6_destroy,
	.get_mtu	= esp6_get_mtu,
	.input		= esp6_input,
	.output		= esp6_output,
	.hdr_offset	= xfrm6_find_1stfragopt,
};

static const struct inet6_protocol esp6_protocol = {
	.handler 	=	xfrm6_rcv,
	.err_handler	=	esp6_err,
	.flags		=	INET6_PROTO_NOPOLICY,
};

static int __init esp6_init(void)
{
	if (xfrm_register_type(&esp6_type, AF_INET6) < 0) {
		printk(KERN_INFO "ipv6 esp init: can't add xfrm type\n");
		return -EAGAIN;
	}
	if (inet6_add_protocol(&esp6_protocol, IPPROTO_ESP) < 0) {
		printk(KERN_INFO "ipv6 esp init: can't add protocol\n");
		xfrm_unregister_type(&esp6_type, AF_INET6);
		return -EAGAIN;
	}

	return 0;
}

static void __exit esp6_fini(void)
{
	if (inet6_del_protocol(&esp6_protocol, IPPROTO_ESP) < 0)
		printk(KERN_INFO "ipv6 esp close: can't remove protocol\n");
	if (xfrm_unregister_type(&esp6_type, AF_INET6) < 0)
		printk(KERN_INFO "ipv6 esp close: can't remove xfrm type\n");
}

module_init(esp6_init);
module_exit(esp6_fini);

MODULE_LICENSE("GPL");
MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ESP);
Commit	Line	Data
1da177e4 LT	1	/*
1da177e4 LT	2	* Copyright (C)2002 USAGI/WIDE Project
1ab1457c	3	*
1da177e4 LT	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License as published by
	6	* the Free Software Foundation; either version 2 of the License, or
	7	* (at your option) any later version.
1ab1457c	8	*
1da177e4 LT	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
1ab1457c	13	*
1da177e4 LT	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write to the Free Software
	16	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	17	*
	18	* Authors
	19	*
1ab1457c	20	* Mitsuru KANDA @USAGI : IPv6 Support
1da177e4 LT	21	* Kazunori MIYAZAWA @USAGI :
1da177e4 LT	22	* Kunihiro Ishiguro <[email protected]>
1ab1457c	23	*
1da177e4 LT	24	* This file is derived from net/ipv4/esp.c
	25	*/
	26
38320c70 HX	27	#include <crypto/aead.h>
38320c70 HX	28	#include <crypto/authenc.h>
6b7326c8	29	#include <linux/err.h>
1da177e4 LT	30	#include <linux/module.h>
	31	#include <net/ip.h>
	32	#include <net/xfrm.h>
	33	#include <net/esp.h>
72998d8c	34	#include <linux/scatterlist.h>
a02a6422	35	#include <linux/kernel.h>
1da177e4 LT	36	#include <linux/pfkeyv2.h>
1da177e4 LT	37	#include <linux/random.h>
38320c70	38	#include <linux/slab.h>
b7c6538c	39	#include <linux/spinlock.h>
1da177e4 LT	40	#include <net/icmp.h>
1da177e4 LT	41	#include <net/ipv6.h>
14c85021	42	#include <net/protocol.h>
1da177e4 LT	43	#include <linux/icmpv6.h>
1da177e4 LT	44
38320c70 HX	45	struct esp_skb_cb {
	46	struct xfrm_skb_cb xfrm;
	47	void *tmp;
	48	};
	49
	50	#define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0]))
	51
040253c9 MW	52	static u32 esp6_get_mtu(struct xfrm_state *x, int mtu);
040253c9 MW	53
38320c70 HX	54	/*
	55	* Allocate an AEAD request structure with extra space for SG and IV.
	56	*
d212a4c2 SK	57	* For alignment considerations the upper 32 bits of the sequence number are
	58	* placed at the front, if present. Followed by the IV, the request and finally
	59	* the SG list.
38320c70 HX	60	*
	61	* TODO: Use spare space in skb for this where possible.
	62	*/
d212a4c2	63	static void esp_alloc_tmp(struct crypto_aead aead, int nfrags, int seqihlen)
38320c70 HX	64	{
	65	unsigned int len;
	66
d212a4c2 SK	67	len = seqihlen;
	68
	69	len += crypto_aead_ivsize(aead);
	70
38320c70 HX	71	if (len) {
	72	len += crypto_aead_alignmask(aead) &
	73	~(crypto_tfm_ctx_alignment() - 1);
	74	len = ALIGN(len, crypto_tfm_ctx_alignment());
	75	}
	76
	77	len += sizeof(struct aead_givcrypt_request) + crypto_aead_reqsize(aead);
	78	len = ALIGN(len, __alignof__(struct scatterlist));
	79
	80	len += sizeof(struct scatterlist) * nfrags;
	81
	82	return kmalloc(len, GFP_ATOMIC);
	83	}
	84
d212a4c2 SK	85	static inline __be32 esp_tmp_seqhi(void tmp)
	86	{
	87	return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32));
	88	}
	89
	90	static inline u8 esp_tmp_iv(struct crypto_aead aead, void *tmp, int seqhilen)
38320c70 HX	91	{
38320c70 HX	92	return crypto_aead_ivsize(aead) ?
d212a4c2 SK	93	PTR_ALIGN((u8 *)tmp + seqhilen,
d212a4c2 SK	94	crypto_aead_alignmask(aead) + 1) : tmp + seqhilen;
38320c70 HX	95	}
	96
	97	static inline struct aead_givcrypt_request *esp_tmp_givreq(
	98	struct crypto_aead aead, u8 iv)
	99	{
	100	struct aead_givcrypt_request *req;
	101
	102	req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead),
	103	crypto_tfm_ctx_alignment());
	104	aead_givcrypt_set_tfm(req, aead);
	105	return req;
	106	}
	107
	108	static inline struct aead_request esp_tmp_req(struct crypto_aead aead, u8 *iv)
	109	{
	110	struct aead_request *req;
	111
	112	req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead),
	113	crypto_tfm_ctx_alignment());
	114	aead_request_set_tfm(req, aead);
	115	return req;
	116	}
	117
	118	static inline struct scatterlist esp_req_sg(struct crypto_aead aead,
	119	struct aead_request *req)
	120	{
	121	return (void *)ALIGN((unsigned long)(req + 1) +
	122	crypto_aead_reqsize(aead),
	123	__alignof__(struct scatterlist));
	124	}
	125
	126	static inline struct scatterlist *esp_givreq_sg(
	127	struct crypto_aead aead, struct aead_givcrypt_request req)
	128	{
	129	return (void *)ALIGN((unsigned long)(req + 1) +
	130	crypto_aead_reqsize(aead),
	131	__alignof__(struct scatterlist));
	132	}
	133
	134	static void esp_output_done(struct crypto_async_request *base, int err)
	135	{
	136	struct sk_buff *skb = base->data;
	137
	138	kfree(ESP_SKB_CB(skb)->tmp);
	139	xfrm_output_resume(skb, err);
	140	}
	141
1da177e4 LT	142	static int esp6_output(struct xfrm_state x, struct sk_buff skb)
	143	{
	144	int err;
87bdc48d	145	struct ip_esp_hdr *esph;
38320c70 HX	146	struct crypto_aead *aead;
	147	struct aead_givcrypt_request *req;
	148	struct scatterlist *sg;
	149	struct scatterlist *asg;
1da177e4	150	struct sk_buff *trailer;
38320c70	151	void *tmp;
1da177e4 LT	152	int blksize;
	153	int clen;
	154	int alen;
040253c9 MW	155	int plen;
040253c9 MW	156	int tfclen;
1da177e4	157	int nfrags;
d212a4c2 SK	158	int assoclen;
	159	int sglists;
	160	int seqhilen;
38320c70	161	u8 *iv;
27a884dc	162	u8 *tail;
d212a4c2	163	__be32 *seqhi;
ea2ae17d	164	struct esp_data *esp = x->data;
1da177e4	165
7b277b1a	166	/* skb is pure payload to encrypt */
1da177e4 LT	167	err = -ENOMEM;
1da177e4 LT	168
38320c70 HX	169	aead = esp->aead;
	170	alen = crypto_aead_authsize(aead);
	171
040253c9 MW	172	tfclen = 0;
	173	if (x->tfcpad) {
	174	struct xfrm_dst dst = (struct xfrm_dst )skb_dst(skb);
	175	u32 padto;
	176
	177	padto = min(x->tfcpad, esp6_get_mtu(x, dst->child_mtu_cached));
	178	if (skb->len < padto)
	179	tfclen = padto - skb->len;
	180	}
38320c70	181	blksize = ALIGN(crypto_aead_blocksize(aead), 4);
040253c9	182	clen = ALIGN(skb->len + 2 + tfclen, blksize);
38320c70 HX	183	if (esp->padlen)
38320c70 HX	184	clen = ALIGN(clen, esp->padlen);
040253c9	185	plen = clen - skb->len - tfclen;
1da177e4	186
040253c9 MW	187	err = skb_cow_data(skb, tfclen + plen + alen, &trailer);
040253c9 MW	188	if (err < 0)
1da177e4	189	goto error;
38320c70 HX	190	nfrags = err;
38320c70 HX	191
d212a4c2 SK	192	assoclen = sizeof(*esph);
	193	sglists = 1;
	194	seqhilen = 0;
	195
	196	if (x->props.flags & XFRM_STATE_ESN) {
	197	sglists += 2;
	198	seqhilen += sizeof(__be32);
	199	assoclen += seqhilen;
	200	}
	201
	202	tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen);
38320c70 HX	203	if (!tmp)
	204	goto error;
	205
d212a4c2 SK	206	seqhi = esp_tmp_seqhi(tmp);
d212a4c2 SK	207	iv = esp_tmp_iv(aead, tmp, seqhilen);
38320c70 HX	208	req = esp_tmp_givreq(aead, iv);
38320c70 HX	209	asg = esp_givreq_sg(aead, req);
d212a4c2	210	sg = asg + sglists;
1da177e4 LT	211
1da177e4 LT	212	/* Fill padding... */
27a884dc	213	tail = skb_tail_pointer(trailer);
040253c9 MW	214	if (tfclen) {
	215	memset(tail, 0, tfclen);
	216	tail += tfclen;
	217	}
1da177e4 LT	218	do {
1da177e4 LT	219	int i;
040253c9	220	for (i = 0; i < plen - 2; i++)
27a884dc	221	tail[i] = i + 1;
1da177e4	222	} while (0);
040253c9 MW	223	tail[plen - 2] = plen - 2;
040253c9 MW	224	tail[plen - 1] = *skb_mac_header(skb);
38320c70	225	pskb_put(skb, trailer, clen - skb->len + alen);
1da177e4	226
7b277b1a	227	skb_push(skb, -skb_network_offset(skb));
87bdc48d	228	esph = ip_esp_hdr(skb);
007f0211	229	*skb_mac_header(skb) = IPPROTO_ESP;
1da177e4 LT	230
1da177e4 LT	231	esph->spi = x->id.spi;
1ce3644a	232	esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
1da177e4	233
38320c70 HX	234	sg_init_table(sg, nfrags);
	235	skb_to_sgvec(skb, sg,
	236	esph->enc_data + crypto_aead_ivsize(aead) - skb->data,
	237	clen + alen);
d212a4c2 SK	238
	239	if ((x->props.flags & XFRM_STATE_ESN)) {
	240	sg_init_table(asg, 3);
	241	sg_set_buf(asg, &esph->spi, sizeof(__be32));
	242	*seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi);
	243	sg_set_buf(asg + 1, seqhi, seqhilen);
	244	sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32));
	245	} else
	246	sg_init_one(asg, esph, sizeof(*esph));
b7c6538c	247
38320c70 HX	248	aead_givcrypt_set_callback(req, 0, esp_output_done, skb);
38320c70 HX	249	aead_givcrypt_set_crypt(req, sg, sg, clen, iv);
d212a4c2	250	aead_givcrypt_set_assoc(req, asg, assoclen);
b318e0e4	251	aead_givcrypt_set_giv(req, esph->enc_data,
1ce3644a	252	XFRM_SKB_CB(skb)->seq.output.low);
1da177e4	253
38320c70 HX	254	ESP_SKB_CB(skb)->tmp = tmp;
	255	err = crypto_aead_givencrypt(req);
	256	if (err == -EINPROGRESS)
	257	goto error;
1da177e4	258
38320c70 HX	259	if (err == -EBUSY)
	260	err = NET_XMIT_DROP;
	261
	262	kfree(tmp);
	263
	264	error:
	265	return err;
	266	}
	267
	268	static int esp_input_done2(struct sk_buff *skb, int err)
	269	{
	270	struct xfrm_state *x = xfrm_input_state(skb);
	271	struct esp_data *esp = x->data;
	272	struct crypto_aead *aead = esp->aead;
	273	int alen = crypto_aead_authsize(aead);
	274	int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead);
	275	int elen = skb->len - hlen;
	276	int hdr_len = skb_network_header_len(skb);
	277	int padlen;
	278	u8 nexthdr[2];
	279
	280	kfree(ESP_SKB_CB(skb)->tmp);
1da177e4	281
6b7326c8	282	if (unlikely(err))
38320c70	283	goto out;
6b7326c8	284
38320c70 HX	285	if (skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2))
38320c70 HX	286	BUG();
1da177e4	287
38320c70 HX	288	err = -EINVAL;
	289	padlen = nexthdr[0];
	290	if (padlen + 2 + alen >= elen) {
	291	LIMIT_NETDEBUG(KERN_WARNING "ipsec esp packet is garbage "
	292	"padlen=%d, elen=%d\n", padlen + 2, elen - alen);
	293	goto out;
1da177e4 LT	294	}
1da177e4 LT	295
38320c70	296	/* ... check padding bits here. Silly. :-) */
b7c6538c	297
38320c70 HX	298	pskb_trim(skb, skb->len - alen - padlen - 2);
	299	__skb_pull(skb, hlen);
	300	skb_set_transport_header(skb, -hdr_len);
	301
	302	err = nexthdr[1];
	303
	304	/* RFC4303: Drop dummy packets without any error */
	305	if (err == IPPROTO_NONE)
	306	err = -EINVAL;
	307
	308	out:
1da177e4 LT	309	return err;
	310	}
	311
38320c70 HX	312	static void esp_input_done(struct crypto_async_request *base, int err)
	313	{
	314	struct sk_buff *skb = base->data;
	315
	316	xfrm_input_resume(skb, esp_input_done2(skb, err));
	317	}
	318
e695633e	319	static int esp6_input(struct xfrm_state x, struct sk_buff skb)
1da177e4	320	{
87bdc48d	321	struct ip_esp_hdr *esph;
1da177e4	322	struct esp_data *esp = x->data;
38320c70 HX	323	struct crypto_aead *aead = esp->aead;
38320c70 HX	324	struct aead_request *req;
1da177e4	325	struct sk_buff *trailer;
38320c70	326	int elen = skb->len - sizeof(*esph) - crypto_aead_ivsize(aead);
1da177e4	327	int nfrags;
d212a4c2 SK	328	int assoclen;
	329	int sglists;
	330	int seqhilen;
1da177e4	331	int ret = 0;
38320c70	332	void *tmp;
d212a4c2	333	__be32 *seqhi;
38320c70 HX	334	u8 *iv;
	335	struct scatterlist *sg;
	336	struct scatterlist *asg;
1da177e4	337
920fc941	338	if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead))) {
1da177e4	339	ret = -EINVAL;
31a4ab93	340	goto out;
1da177e4 LT	341	}
1da177e4 LT	342
38320c70	343	if (elen <= 0) {
1da177e4	344	ret = -EINVAL;
31a4ab93	345	goto out;
1da177e4	346	}
1da177e4	347
0ebea8ef HX	348	if ((nfrags = skb_cow_data(skb, 0, &trailer)) < 0) {
	349	ret = -EINVAL;
	350	goto out;
	351	}
	352
38320c70	353	ret = -ENOMEM;
d212a4c2 SK	354
	355	assoclen = sizeof(*esph);
	356	sglists = 1;
	357	seqhilen = 0;
	358
	359	if (x->props.flags & XFRM_STATE_ESN) {
	360	sglists += 2;
	361	seqhilen += sizeof(__be32);
	362	assoclen += seqhilen;
	363	}
	364
	365	tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen);
38320c70 HX	366	if (!tmp)
38320c70 HX	367	goto out;
1da177e4	368
38320c70	369	ESP_SKB_CB(skb)->tmp = tmp;
d212a4c2 SK	370	seqhi = esp_tmp_seqhi(tmp);
d212a4c2 SK	371	iv = esp_tmp_iv(aead, tmp, seqhilen);
38320c70 HX	372	req = esp_tmp_req(aead, iv);
38320c70 HX	373	asg = esp_req_sg(aead, req);
c0a56e64	374	sg = asg + sglists;
1da177e4	375
38320c70	376	skb->ip_summed = CHECKSUM_NONE;
1da177e4	377
87bdc48d	378	esph = (struct ip_esp_hdr *)skb->data;
1da177e4 LT	379
1da177e4 LT	380	/* Get ivec. This can be wrong, check against another impls. */
38320c70	381	iv = esph->enc_data;
0ebea8ef	382
38320c70 HX	383	sg_init_table(sg, nfrags);
38320c70 HX	384	skb_to_sgvec(skb, sg, sizeof(*esph) + crypto_aead_ivsize(aead), elen);
d212a4c2 SK	385
	386	if ((x->props.flags & XFRM_STATE_ESN)) {
	387	sg_init_table(asg, 3);
	388	sg_set_buf(asg, &esph->spi, sizeof(__be32));
	389	*seqhi = XFRM_SKB_CB(skb)->seq.input.hi;
	390	sg_set_buf(asg + 1, seqhi, seqhilen);
	391	sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32));
	392	} else
	393	sg_init_one(asg, esph, sizeof(*esph));
0ebea8ef	394
38320c70 HX	395	aead_request_set_callback(req, 0, esp_input_done, skb);
38320c70 HX	396	aead_request_set_crypt(req, sg, sg, elen, iv);
d212a4c2	397	aead_request_set_assoc(req, asg, assoclen);
1da177e4	398
38320c70 HX	399	ret = crypto_aead_decrypt(req);
	400	if (ret == -EINPROGRESS)
	401	goto out;
95a02cfd	402
38320c70	403	ret = esp_input_done2(skb, ret);
1da177e4 LT	404
1da177e4 LT	405	out:
1da177e4 LT	406	return ret;
	407	}
	408
c5c25238	409	static u32 esp6_get_mtu(struct xfrm_state *x, int mtu)
1da177e4 LT	410	{
1da177e4 LT	411	struct esp_data *esp = x->data;
38320c70 HX	412	u32 blksize = ALIGN(crypto_aead_blocksize(esp->aead), 4);
38320c70 HX	413	u32 align = max_t(u32, blksize, esp->padlen);
c5c25238	414	u32 rem;
1da177e4	415
38320c70	416	mtu -= x->props.header_len + crypto_aead_authsize(esp->aead);
c5c25238 PM	417	rem = mtu & (align - 1);
	418	mtu &= ~(align - 1);
	419
	420	if (x->props.mode != XFRM_MODE_TUNNEL) {
d4875b04	421	u32 padsize = ((blksize - 1) & 7) + 1;
c5c25238 PM	422	mtu -= blksize - padsize;
c5c25238 PM	423	mtu += min_t(u32, blksize - padsize, rem);
1da177e4	424	}
1da177e4	425
c5c25238	426	return mtu - 2;
1da177e4 LT	427	}
	428
	429	static void esp6_err(struct sk_buff skb, struct inet6_skb_parm opt,
d5fdd6ba	430	u8 type, u8 code, int offset, __be32 info)
1da177e4	431	{
4fb236ba	432	struct net *net = dev_net(skb->dev);
b71d1d42	433	const struct ipv6hdr iph = (const struct ipv6hdr )skb->data;
87bdc48d	434	struct ip_esp_hdr esph = (struct ip_esp_hdr )(skb->data + offset);
1da177e4 LT	435	struct xfrm_state *x;
1da177e4 LT	436
1ab1457c	437	if (type != ICMPV6_DEST_UNREACH &&
1da177e4 LT	438	type != ICMPV6_PKT_TOOBIG)
	439	return;
	440
b71d1d42 ED	441	x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
b71d1d42 ED	442	esph->spi, IPPROTO_ESP, AF_INET6);
1da177e4 LT	443	if (!x)
1da177e4 LT	444	return;
5b095d98	445	printk(KERN_DEBUG "pmtu discovery on SA ESP/%08x/%pI6\n",
0c6ce78a	446	ntohl(esph->spi), &iph->daddr);
1da177e4 LT	447	xfrm_state_put(x);
	448	}
	449
	450	static void esp6_destroy(struct xfrm_state *x)
	451	{
	452	struct esp_data *esp = x->data;
	453
	454	if (!esp)
	455	return;
	456
38320c70	457	crypto_free_aead(esp->aead);
1da177e4 LT	458	kfree(esp);
	459	}
	460
1a6509d9 HX	461	static int esp_init_aead(struct xfrm_state *x)
	462	{
	463	struct esp_data *esp = x->data;
	464	struct crypto_aead *aead;
	465	int err;
	466
	467	aead = crypto_alloc_aead(x->aead->alg_name, 0, 0);
	468	err = PTR_ERR(aead);
	469	if (IS_ERR(aead))
	470	goto error;
	471
	472	esp->aead = aead;
	473
	474	err = crypto_aead_setkey(aead, x->aead->alg_key,
	475	(x->aead->alg_key_len + 7) / 8);
	476	if (err)
	477	goto error;
	478
	479	err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8);
	480	if (err)
	481	goto error;
	482
	483	error:
	484	return err;
	485	}
	486
	487	static int esp_init_authenc(struct xfrm_state *x)
1da177e4	488	{
1a6509d9	489	struct esp_data *esp = x->data;
38320c70 HX	490	struct crypto_aead *aead;
	491	struct crypto_authenc_key_param *param;
	492	struct rtattr *rta;
	493	char *key;
	494	char *p;
	495	char authenc_name[CRYPTO_MAX_ALG_NAME];
38320c70 HX	496	unsigned int keylen;
38320c70 HX	497	int err;
1da177e4	498
1a6509d9	499	err = -EINVAL;
1da177e4	500	if (x->ealg == NULL)
1a6509d9	501	goto error;
38320c70	502
1a6509d9	503	err = -ENAMETOOLONG;
d212a4c2 SK	504
	505	if ((x->props.flags & XFRM_STATE_ESN)) {
	506	if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
	507	"authencesn(%s,%s)",
	508	x->aalg ? x->aalg->alg_name : "digest_null",
	509	x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME)
	510	goto error;
	511	} else {
	512	if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
	513	"authenc(%s,%s)",
	514	x->aalg ? x->aalg->alg_name : "digest_null",
	515	x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME)
	516	goto error;
	517	}
38320c70 HX	518
	519	aead = crypto_alloc_aead(authenc_name, 0, 0);
	520	err = PTR_ERR(aead);
	521	if (IS_ERR(aead))
	522	goto error;
	523
	524	esp->aead = aead;
	525
	526	keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) +
	527	(x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param));
	528	err = -ENOMEM;
	529	key = kmalloc(keylen, GFP_KERNEL);
	530	if (!key)
	531	goto error;
	532
	533	p = key;
	534	rta = (void *)p;
	535	rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
	536	rta->rta_len = RTA_LENGTH(sizeof(*param));
	537	param = RTA_DATA(rta);
	538	p += RTA_SPACE(sizeof(*param));
	539
1da177e4 LT	540	if (x->aalg) {
	541	struct xfrm_algo_desc *aalg_desc;
	542
38320c70 HX	543	memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8);
38320c70 HX	544	p += (x->aalg->alg_key_len + 7) / 8;
1ab1457c	545
1da177e4 LT	546	aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
1da177e4 LT	547	BUG_ON(!aalg_desc);
1ab1457c	548
38320c70	549	err = -EINVAL;
1da177e4	550	if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
38320c70	551	crypto_aead_authsize(aead)) {
07d4ee58 HX	552	NETDEBUG(KERN_INFO "ESP: %s digestsize %u != %hu\n",
07d4ee58 HX	553	x->aalg->alg_name,
38320c70	554	crypto_aead_authsize(aead),
07d4ee58	555	aalg_desc->uinfo.auth.icv_fullbits/8);
38320c70	556	goto free_key;
1da177e4	557	}
1ab1457c	558
38320c70	559	err = crypto_aead_setauthsize(
8f8a088c	560	aead, x->aalg->alg_trunc_len / 8);
38320c70 HX	561	if (err)
38320c70 HX	562	goto free_key;
1da177e4	563	}
38320c70	564
38320c70 HX	565	param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8);
	566	memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8);
	567
	568	err = crypto_aead_setkey(aead, key, keylen);
	569
	570	free_key:
	571	kfree(key);
	572
1a6509d9 HX	573	error:
	574	return err;
	575	}
	576
	577	static int esp6_init_state(struct xfrm_state *x)
	578	{
	579	struct esp_data *esp;
	580	struct crypto_aead *aead;
	581	u32 align;
	582	int err;
	583
	584	if (x->encap)
	585	return -EINVAL;
	586
	587	esp = kzalloc(sizeof(*esp), GFP_KERNEL);
	588	if (esp == NULL)
	589	return -ENOMEM;
	590
	591	x->data = esp;
	592
	593	if (x->aead)
	594	err = esp_init_aead(x);
	595	else
	596	err = esp_init_authenc(x);
	597
38320c70	598	if (err)
1da177e4	599	goto error;
38320c70	600
1a6509d9 HX	601	aead = esp->aead;
	602
	603	esp->padlen = 0;
	604
38320c70 HX	605	x->props.header_len = sizeof(struct ip_esp_hdr) +
38320c70 HX	606	crypto_aead_ivsize(aead);
ca68145f HX	607	switch (x->props.mode) {
ca68145f HX	608	case XFRM_MODE_BEET:
abf5cdb8 JK	609	if (x->sel.family != AF_INET6)
	610	x->props.header_len += IPV4_BEET_PHMAXLEN +
	611	(sizeof(struct ipv6hdr) - sizeof(struct iphdr));
	612	break;
ca68145f HX	613	case XFRM_MODE_TRANSPORT:
	614	break;
	615	case XFRM_MODE_TUNNEL:
1da177e4	616	x->props.header_len += sizeof(struct ipv6hdr);
ea2c47b4	617	break;
ca68145f HX	618	default:
	619	goto error;
	620	}
38320c70 HX	621
	622	align = ALIGN(crypto_aead_blocksize(aead), 4);
	623	if (esp->padlen)
	624	align = max_t(u32, align, esp->padlen);
	625	x->props.trailer_len = align + 1 + crypto_aead_authsize(esp->aead);
1da177e4 LT	626
1da177e4 LT	627	error:
38320c70	628	return err;
1da177e4 LT	629	}
1da177e4 LT	630
533cb5b0	631	static const struct xfrm_type esp6_type =
1da177e4 LT	632	{
	633	.description = "ESP6",
	634	.owner = THIS_MODULE,
	635	.proto = IPPROTO_ESP,
436a0a40	636	.flags = XFRM_TYPE_REPLAY_PROT,
1da177e4 LT	637	.init_state = esp6_init_state,
1da177e4 LT	638	.destructor = esp6_destroy,
c5c25238	639	.get_mtu = esp6_get_mtu,
1da177e4	640	.input = esp6_input,
aee5adb4 MN	641	.output = esp6_output,
aee5adb4 MN	642	.hdr_offset = xfrm6_find_1stfragopt,
1da177e4 LT	643	};
1da177e4 LT	644
41135cc8	645	static const struct inet6_protocol esp6_protocol = {
1da177e4 LT	646	.handler = xfrm6_rcv,
	647	.err_handler = esp6_err,
	648	.flags = INET6_PROTO_NOPOLICY,
	649	};
	650
	651	static int __init esp6_init(void)
	652	{
	653	if (xfrm_register_type(&esp6_type, AF_INET6) < 0) {
	654	printk(KERN_INFO "ipv6 esp init: can't add xfrm type\n");
	655	return -EAGAIN;
	656	}
	657	if (inet6_add_protocol(&esp6_protocol, IPPROTO_ESP) < 0) {
	658	printk(KERN_INFO "ipv6 esp init: can't add protocol\n");
	659	xfrm_unregister_type(&esp6_type, AF_INET6);
	660	return -EAGAIN;
	661	}
	662
	663	return 0;
	664	}
	665
	666	static void __exit esp6_fini(void)
	667	{
	668	if (inet6_del_protocol(&esp6_protocol, IPPROTO_ESP) < 0)
	669	printk(KERN_INFO "ipv6 esp close: can't remove protocol\n");
	670	if (xfrm_unregister_type(&esp6_type, AF_INET6) < 0)
	671	printk(KERN_INFO "ipv6 esp close: can't remove xfrm type\n");
	672	}
	673
	674	module_init(esp6_init);
	675	module_exit(esp6_fini);
	676
	677	MODULE_LICENSE("GPL");
d3d6dd3a	678	MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ESP);