[mirror_ubuntu-hirsute-kernel.git] / drivers / crypto / ccp / ccp-crypto-aes-xts.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * AMD Cryptographic Coprocessor (CCP) AES XTS crypto API support
 *
 * Copyright (C) 2013,2017 Advanced Micro Devices, Inc.
 *
 * Author: Gary R Hook <gary.hook@amd.com>
 * Author: Tom Lendacky <thomas.lendacky@amd.com>
 */

#include <linux/module.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/scatterlist.h>
#include <crypto/aes.h>
#include <crypto/xts.h>
#include <crypto/internal/skcipher.h>
#include <crypto/scatterwalk.h>

#include "ccp-crypto.h"

struct ccp_aes_xts_def {
	const char *name;
	const char *drv_name;
};

static struct ccp_aes_xts_def aes_xts_algs[] = {
	{
		.name		= "xts(aes)",
		.drv_name	= "xts-aes-ccp",
	},
};

struct ccp_unit_size_map {
	unsigned int size;
	u32 value;
};

static struct ccp_unit_size_map xts_unit_sizes[] = {
	{
		.size   = 16,
		.value	= CCP_XTS_AES_UNIT_SIZE_16,
	},
	{
		.size   = 512,
		.value	= CCP_XTS_AES_UNIT_SIZE_512,
	},
	{
		.size   = 1024,
		.value	= CCP_XTS_AES_UNIT_SIZE_1024,
	},
	{
		.size   = 2048,
		.value	= CCP_XTS_AES_UNIT_SIZE_2048,
	},
	{
		.size   = 4096,
		.value	= CCP_XTS_AES_UNIT_SIZE_4096,
	},
};

static int ccp_aes_xts_complete(struct crypto_async_request *async_req, int ret)
{
	struct ablkcipher_request *req = ablkcipher_request_cast(async_req);
	struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);

	if (ret)
		return ret;

	memcpy(req->info, rctx->iv, AES_BLOCK_SIZE);

	return 0;
}

static int ccp_aes_xts_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
			      unsigned int key_len)
{
	struct crypto_tfm *xfm = crypto_ablkcipher_tfm(tfm);
	struct ccp_ctx *ctx = crypto_tfm_ctx(xfm);
	unsigned int ccpversion = ccp_version();
	int ret;

	ret = xts_check_key(xfm, key, key_len);
	if (ret)
		return ret;

	/* Version 3 devices support 128-bit keys; version 5 devices can
	 * accommodate 128- and 256-bit keys.
	 */
	switch (key_len) {
	case AES_KEYSIZE_128 * 2:
		memcpy(ctx->u.aes.key, key, key_len);
		break;
	case AES_KEYSIZE_256 * 2:
		if (ccpversion > CCP_VERSION(3, 0))
			memcpy(ctx->u.aes.key, key, key_len);
		break;
	}
	ctx->u.aes.key_len = key_len / 2;
	sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);

	return crypto_sync_skcipher_setkey(ctx->u.aes.tfm_skcipher, key, key_len);
}

static int ccp_aes_xts_crypt(struct ablkcipher_request *req,
			     unsigned int encrypt)
{
	struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
	struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
	unsigned int ccpversion = ccp_version();
	unsigned int fallback = 0;
	unsigned int unit;
	u32 unit_size;
	int ret;

	if (!ctx->u.aes.key_len)
		return -EINVAL;

	if (req->nbytes & (AES_BLOCK_SIZE - 1))
		return -EINVAL;

	if (!req->info)
		return -EINVAL;

	/* Check conditions under which the CCP can fulfill a request. The
	 * device can handle input plaintext of a length that is a multiple
	 * of the unit_size, bug the crypto implementation only supports
	 * the unit_size being equal to the input length. This limits the
	 * number of scenarios we can handle.
	 */
	unit_size = CCP_XTS_AES_UNIT_SIZE__LAST;
	for (unit = 0; unit < ARRAY_SIZE(xts_unit_sizes); unit++) {
		if (req->nbytes == xts_unit_sizes[unit].size) {
			unit_size = unit;
			break;
		}
	}
	/* The CCP has restrictions on block sizes. Also, a version 3 device
	 * only supports AES-128 operations; version 5 CCPs support both
	 * AES-128 and -256 operations.
	 */
	if (unit_size == CCP_XTS_AES_UNIT_SIZE__LAST)
		fallback = 1;
	if ((ccpversion < CCP_VERSION(5, 0)) &&
	    (ctx->u.aes.key_len != AES_KEYSIZE_128))
		fallback = 1;
	if ((ctx->u.aes.key_len != AES_KEYSIZE_128) &&
	    (ctx->u.aes.key_len != AES_KEYSIZE_256))
		fallback = 1;
	if (fallback) {
		SYNC_SKCIPHER_REQUEST_ON_STACK(subreq,
					       ctx->u.aes.tfm_skcipher);

		/* Use the fallback to process the request for any
		 * unsupported unit sizes or key sizes
		 */
		skcipher_request_set_sync_tfm(subreq, ctx->u.aes.tfm_skcipher);
		skcipher_request_set_callback(subreq, req->base.flags,
					      NULL, NULL);
		skcipher_request_set_crypt(subreq, req->src, req->dst,
					   req->nbytes, req->info);
		ret = encrypt ? crypto_skcipher_encrypt(subreq) :
				crypto_skcipher_decrypt(subreq);
		skcipher_request_zero(subreq);
		return ret;
	}

	memcpy(rctx->iv, req->info, AES_BLOCK_SIZE);
	sg_init_one(&rctx->iv_sg, rctx->iv, AES_BLOCK_SIZE);

	memset(&rctx->cmd, 0, sizeof(rctx->cmd));
	INIT_LIST_HEAD(&rctx->cmd.entry);
	rctx->cmd.engine = CCP_ENGINE_XTS_AES_128;
	rctx->cmd.u.xts.type = CCP_AES_TYPE_128;
	rctx->cmd.u.xts.action = (encrypt) ? CCP_AES_ACTION_ENCRYPT
					   : CCP_AES_ACTION_DECRYPT;
	rctx->cmd.u.xts.unit_size = unit_size;
	rctx->cmd.u.xts.key = &ctx->u.aes.key_sg;
	rctx->cmd.u.xts.key_len = ctx->u.aes.key_len;
	rctx->cmd.u.xts.iv = &rctx->iv_sg;
	rctx->cmd.u.xts.iv_len = AES_BLOCK_SIZE;
	rctx->cmd.u.xts.src = req->src;
	rctx->cmd.u.xts.src_len = req->nbytes;
	rctx->cmd.u.xts.dst = req->dst;

	ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);

	return ret;
}

static int ccp_aes_xts_encrypt(struct ablkcipher_request *req)
{
	return ccp_aes_xts_crypt(req, 1);
}

static int ccp_aes_xts_decrypt(struct ablkcipher_request *req)
{
	return ccp_aes_xts_crypt(req, 0);
}

static int ccp_aes_xts_cra_init(struct crypto_tfm *tfm)
{
	struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
	struct crypto_sync_skcipher *fallback_tfm;

	ctx->complete = ccp_aes_xts_complete;
	ctx->u.aes.key_len = 0;

	fallback_tfm = crypto_alloc_sync_skcipher("xts(aes)", 0,
					     CRYPTO_ALG_ASYNC |
					     CRYPTO_ALG_NEED_FALLBACK);
	if (IS_ERR(fallback_tfm)) {
		pr_warn("could not load fallback driver xts(aes)\n");
		return PTR_ERR(fallback_tfm);
	}
	ctx->u.aes.tfm_skcipher = fallback_tfm;

	tfm->crt_ablkcipher.reqsize = sizeof(struct ccp_aes_req_ctx);

	return 0;
}

static void ccp_aes_xts_cra_exit(struct crypto_tfm *tfm)
{
	struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);

	crypto_free_sync_skcipher(ctx->u.aes.tfm_skcipher);
}

static int ccp_register_aes_xts_alg(struct list_head *head,
				    const struct ccp_aes_xts_def *def)
{
	struct ccp_crypto_ablkcipher_alg *ccp_alg;
	struct crypto_alg *alg;
	int ret;

	ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
	if (!ccp_alg)
		return -ENOMEM;

	INIT_LIST_HEAD(&ccp_alg->entry);

	alg = &ccp_alg->alg;

	snprintf(alg->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
	snprintf(alg->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
		 def->drv_name);
	alg->cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC |
			 CRYPTO_ALG_KERN_DRIVER_ONLY |
			 CRYPTO_ALG_NEED_FALLBACK;
	alg->cra_blocksize = AES_BLOCK_SIZE;
	alg->cra_ctxsize = sizeof(struct ccp_ctx);
	alg->cra_priority = CCP_CRA_PRIORITY;
	alg->cra_type = &crypto_ablkcipher_type;
	alg->cra_ablkcipher.setkey = ccp_aes_xts_setkey;
	alg->cra_ablkcipher.encrypt = ccp_aes_xts_encrypt;
	alg->cra_ablkcipher.decrypt = ccp_aes_xts_decrypt;
	alg->cra_ablkcipher.min_keysize = AES_MIN_KEY_SIZE * 2;
	alg->cra_ablkcipher.max_keysize = AES_MAX_KEY_SIZE * 2;
	alg->cra_ablkcipher.ivsize = AES_BLOCK_SIZE;
	alg->cra_init = ccp_aes_xts_cra_init;
	alg->cra_exit = ccp_aes_xts_cra_exit;
	alg->cra_module = THIS_MODULE;

	ret = crypto_register_alg(alg);
	if (ret) {
		pr_err("%s ablkcipher algorithm registration error (%d)\n",
		       alg->cra_name, ret);
		kfree(ccp_alg);
		return ret;
	}

	list_add(&ccp_alg->entry, head);

	return 0;
}

int ccp_register_aes_xts_algs(struct list_head *head)
{
	int i, ret;

	for (i = 0; i < ARRAY_SIZE(aes_xts_algs); i++) {
		ret = ccp_register_aes_xts_alg(head, &aes_xts_algs[i]);
		if (ret)
			return ret;
	}

	return 0;
}
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
1d6b8a6f TL	2	/*
	3	* AMD Cryptographic Coprocessor (CCP) AES XTS crypto API support
	4	*
e652399e	5	* Copyright (C) 2013,2017 Advanced Micro Devices, Inc.
1d6b8a6f	6	*
e652399e	7	* Author: Gary R Hook <gary.hook@amd.com>
1d6b8a6f	8	* Author: Tom Lendacky <thomas.lendacky@amd.com>
1d6b8a6f TL	9	*/
	10
	11	#include <linux/module.h>
	12	#include <linux/sched.h>
	13	#include <linux/delay.h>
	14	#include <linux/scatterlist.h>
1d6b8a6f	15	#include <crypto/aes.h>
47f27f16	16	#include <crypto/xts.h>
241118de	17	#include <crypto/internal/skcipher.h>
1d6b8a6f TL	18	#include <crypto/scatterwalk.h>
	19
	20	#include "ccp-crypto.h"
	21
1d6b8a6f TL	22	struct ccp_aes_xts_def {
	23	const char *name;
	24	const char *drv_name;
	25	};
	26
	27	static struct ccp_aes_xts_def aes_xts_algs[] = {
	28	{
	29	.name = "xts(aes)",
	30	.drv_name = "xts-aes-ccp",
	31	},
	32	};
	33
	34	struct ccp_unit_size_map {
	35	unsigned int size;
	36	u32 value;
	37	};
	38
7f7216cf	39	static struct ccp_unit_size_map xts_unit_sizes[] = {
1d6b8a6f	40	{
7f7216cf GH	41	.size = 16,
7f7216cf GH	42	.value = CCP_XTS_AES_UNIT_SIZE_16,
1d6b8a6f TL	43	},
1d6b8a6f TL	44	{
7f7216cf	45	.size = 512,
1d6b8a6f TL	46	.value = CCP_XTS_AES_UNIT_SIZE_512,
	47	},
	48	{
7f7216cf GH	49	.size = 1024,
7f7216cf GH	50	.value = CCP_XTS_AES_UNIT_SIZE_1024,
1d6b8a6f TL	51	},
1d6b8a6f TL	52	{
7f7216cf GH	53	.size = 2048,
7f7216cf GH	54	.value = CCP_XTS_AES_UNIT_SIZE_2048,
1d6b8a6f TL	55	},
1d6b8a6f TL	56	{
7f7216cf GH	57	.size = 4096,
7f7216cf GH	58	.value = CCP_XTS_AES_UNIT_SIZE_4096,
1d6b8a6f TL	59	},
	60	};
	61
	62	static int ccp_aes_xts_complete(struct crypto_async_request *async_req, int ret)
	63	{
	64	struct ablkcipher_request *req = ablkcipher_request_cast(async_req);
	65	struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
	66
	67	if (ret)
	68	return ret;
	69
	70	memcpy(req->info, rctx->iv, AES_BLOCK_SIZE);
	71
	72	return 0;
	73	}
	74
	75	static int ccp_aes_xts_setkey(struct crypto_ablkcipher tfm, const u8 key,
	76	unsigned int key_len)
	77	{
47f27f16 GH	78	struct crypto_tfm *xfm = crypto_ablkcipher_tfm(tfm);
47f27f16 GH	79	struct ccp_ctx *ctx = crypto_tfm_ctx(xfm);
5060ffc9	80	unsigned int ccpversion = ccp_version();
47f27f16 GH	81	int ret;
	82
	83	ret = xts_check_key(xfm, key, key_len);
	84	if (ret)
	85	return ret;
1d6b8a6f	86
5060ffc9 GH	87	/* Version 3 devices support 128-bit keys; version 5 devices can
5060ffc9 GH	88	* accommodate 128- and 256-bit keys.
1d6b8a6f TL	89	*/
	90	switch (key_len) {
	91	case AES_KEYSIZE_128 * 2:
	92	memcpy(ctx->u.aes.key, key, key_len);
	93	break;
5060ffc9 GH	94	case AES_KEYSIZE_256 * 2:
	95	if (ccpversion > CCP_VERSION(3, 0))
	96	memcpy(ctx->u.aes.key, key, key_len);
	97	break;
1d6b8a6f TL	98	}
	99	ctx->u.aes.key_len = key_len / 2;
	100	sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);
	101
7f28615d	102	return crypto_sync_skcipher_setkey(ctx->u.aes.tfm_skcipher, key, key_len);
1d6b8a6f TL	103	}
	104
	105	static int ccp_aes_xts_crypt(struct ablkcipher_request *req,
	106	unsigned int encrypt)
	107	{
1d6b8a6f TL	108	struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
1d6b8a6f TL	109	struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
5060ffc9 GH	110	unsigned int ccpversion = ccp_version();
5060ffc9 GH	111	unsigned int fallback = 0;
1d6b8a6f	112	unsigned int unit;
ab6a11a7	113	u32 unit_size;
1d6b8a6f TL	114	int ret;
1d6b8a6f TL	115
369f3dab	116	if (!ctx->u.aes.key_len)
1d6b8a6f	117	return -EINVAL;
1d6b8a6f	118
369f3dab	119	if (req->nbytes & (AES_BLOCK_SIZE - 1))
1d6b8a6f	120	return -EINVAL;
1d6b8a6f	121
369f3dab	122	if (!req->info)
1d6b8a6f	123	return -EINVAL;
1d6b8a6f	124
7f7216cf GH	125	/* Check conditions under which the CCP can fulfill a request. The
	126	* device can handle input plaintext of a length that is a multiple
	127	* of the unit_size, bug the crypto implementation only supports
	128	* the unit_size being equal to the input length. This limits the
	129	* number of scenarios we can handle.
	130	*/
ab6a11a7	131	unit_size = CCP_XTS_AES_UNIT_SIZE__LAST;
7f7216cf GH	132	for (unit = 0; unit < ARRAY_SIZE(xts_unit_sizes); unit++) {
	133	if (req->nbytes == xts_unit_sizes[unit].size) {
	134	unit_size = unit;
	135	break;
ab6a11a7 TL	136	}
ab6a11a7 TL	137	}
5060ffc9 GH	138	/* The CCP has restrictions on block sizes. Also, a version 3 device
	139	* only supports AES-128 operations; version 5 CCPs support both
	140	* AES-128 and -256 operations.
	141	*/
	142	if (unit_size == CCP_XTS_AES_UNIT_SIZE__LAST)
	143	fallback = 1;
	144	if ((ccpversion < CCP_VERSION(5, 0)) &&
	145	(ctx->u.aes.key_len != AES_KEYSIZE_128))
	146	fallback = 1;
	147	if ((ctx->u.aes.key_len != AES_KEYSIZE_128) &&
	148	(ctx->u.aes.key_len != AES_KEYSIZE_256))
	149	fallback = 1;
	150	if (fallback) {
7f28615d KC	151	SYNC_SKCIPHER_REQUEST_ON_STACK(subreq,
7f28615d KC	152	ctx->u.aes.tfm_skcipher);
241118de	153
1d6b8a6f TL	154	/* Use the fallback to process the request for any
	155	* unsupported unit sizes or key sizes
	156	*/
7f28615d	157	skcipher_request_set_sync_tfm(subreq, ctx->u.aes.tfm_skcipher);
241118de HX	158	skcipher_request_set_callback(subreq, req->base.flags,
	159	NULL, NULL);
	160	skcipher_request_set_crypt(subreq, req->src, req->dst,
	161	req->nbytes, req->info);
	162	ret = encrypt ? crypto_skcipher_encrypt(subreq) :
	163	crypto_skcipher_decrypt(subreq);
	164	skcipher_request_zero(subreq);
1d6b8a6f TL	165	return ret;
	166	}
	167
	168	memcpy(rctx->iv, req->info, AES_BLOCK_SIZE);
	169	sg_init_one(&rctx->iv_sg, rctx->iv, AES_BLOCK_SIZE);
	170
	171	memset(&rctx->cmd, 0, sizeof(rctx->cmd));
	172	INIT_LIST_HEAD(&rctx->cmd.entry);
	173	rctx->cmd.engine = CCP_ENGINE_XTS_AES_128;
e652399e	174	rctx->cmd.u.xts.type = CCP_AES_TYPE_128;
1d6b8a6f TL	175	rctx->cmd.u.xts.action = (encrypt) ? CCP_AES_ACTION_ENCRYPT
1d6b8a6f TL	176	: CCP_AES_ACTION_DECRYPT;
ab6a11a7	177	rctx->cmd.u.xts.unit_size = unit_size;
1d6b8a6f TL	178	rctx->cmd.u.xts.key = &ctx->u.aes.key_sg;
	179	rctx->cmd.u.xts.key_len = ctx->u.aes.key_len;
	180	rctx->cmd.u.xts.iv = &rctx->iv_sg;
	181	rctx->cmd.u.xts.iv_len = AES_BLOCK_SIZE;
	182	rctx->cmd.u.xts.src = req->src;
	183	rctx->cmd.u.xts.src_len = req->nbytes;
	184	rctx->cmd.u.xts.dst = req->dst;
	185
	186	ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
	187
	188	return ret;
	189	}
	190
	191	static int ccp_aes_xts_encrypt(struct ablkcipher_request *req)
	192	{
	193	return ccp_aes_xts_crypt(req, 1);
	194	}
	195
	196	static int ccp_aes_xts_decrypt(struct ablkcipher_request *req)
	197	{
	198	return ccp_aes_xts_crypt(req, 0);
	199	}
	200
	201	static int ccp_aes_xts_cra_init(struct crypto_tfm *tfm)
	202	{
	203	struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
7f28615d	204	struct crypto_sync_skcipher *fallback_tfm;
1d6b8a6f TL	205
	206	ctx->complete = ccp_aes_xts_complete;
	207	ctx->u.aes.key_len = 0;
	208
7f28615d	209	fallback_tfm = crypto_alloc_sync_skcipher("xts(aes)", 0,
241118de HX	210	CRYPTO_ALG_ASYNC \|
241118de HX	211	CRYPTO_ALG_NEED_FALLBACK);
1d6b8a6f	212	if (IS_ERR(fallback_tfm)) {
241118de	213	pr_warn("could not load fallback driver xts(aes)\n");
1d6b8a6f TL	214	return PTR_ERR(fallback_tfm);
1d6b8a6f TL	215	}
241118de	216	ctx->u.aes.tfm_skcipher = fallback_tfm;
1d6b8a6f	217
241118de	218	tfm->crt_ablkcipher.reqsize = sizeof(struct ccp_aes_req_ctx);
1d6b8a6f TL	219
	220	return 0;
	221	}
	222
	223	static void ccp_aes_xts_cra_exit(struct crypto_tfm *tfm)
	224	{
	225	struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
	226
7f28615d	227	crypto_free_sync_skcipher(ctx->u.aes.tfm_skcipher);
1d6b8a6f TL	228	}
1d6b8a6f TL	229
1d6b8a6f TL	230	static int ccp_register_aes_xts_alg(struct list_head *head,
	231	const struct ccp_aes_xts_def *def)
	232	{
	233	struct ccp_crypto_ablkcipher_alg *ccp_alg;
	234	struct crypto_alg *alg;
	235	int ret;
	236
	237	ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
	238	if (!ccp_alg)
	239	return -ENOMEM;
	240
	241	INIT_LIST_HEAD(&ccp_alg->entry);
	242
	243	alg = &ccp_alg->alg;
	244
	245	snprintf(alg->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
	246	snprintf(alg->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
	247	def->drv_name);
	248	alg->cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER \| CRYPTO_ALG_ASYNC \|
	249	CRYPTO_ALG_KERN_DRIVER_ONLY \|
	250	CRYPTO_ALG_NEED_FALLBACK;
	251	alg->cra_blocksize = AES_BLOCK_SIZE;
	252	alg->cra_ctxsize = sizeof(struct ccp_ctx);
	253	alg->cra_priority = CCP_CRA_PRIORITY;
	254	alg->cra_type = &crypto_ablkcipher_type;
	255	alg->cra_ablkcipher.setkey = ccp_aes_xts_setkey;
	256	alg->cra_ablkcipher.encrypt = ccp_aes_xts_encrypt;
	257	alg->cra_ablkcipher.decrypt = ccp_aes_xts_decrypt;
	258	alg->cra_ablkcipher.min_keysize = AES_MIN_KEY_SIZE * 2;
	259	alg->cra_ablkcipher.max_keysize = AES_MAX_KEY_SIZE * 2;
	260	alg->cra_ablkcipher.ivsize = AES_BLOCK_SIZE;
	261	alg->cra_init = ccp_aes_xts_cra_init;
	262	alg->cra_exit = ccp_aes_xts_cra_exit;
	263	alg->cra_module = THIS_MODULE;
	264
	265	ret = crypto_register_alg(alg);
	266	if (ret) {
	267	pr_err("%s ablkcipher algorithm registration error (%d)\n",
8db88467	268	alg->cra_name, ret);
1d6b8a6f TL	269	kfree(ccp_alg);
	270	return ret;
	271	}
	272
	273	list_add(&ccp_alg->entry, head);
	274
	275	return 0;
	276	}
	277
	278	int ccp_register_aes_xts_algs(struct list_head *head)
	279	{
	280	int i, ret;
	281
	282	for (i = 0; i < ARRAY_SIZE(aes_xts_algs); i++) {
	283	ret = ccp_register_aes_xts_alg(head, &aes_xts_algs[i]);
	284	if (ret)
	285	return ret;
	286	}
	287
	288	return 0;
	289	}