[deliverable/linux.git] / drivers / crypto / ccp / ccp-crypto-aes-xts.c

/*
 * AMD Cryptographic Coprocessor (CCP) AES XTS crypto API support
 *
 * Copyright (C) 2013 Advanced Micro Devices, Inc.
 *
 * Author: Tom Lendacky <thomas.lendacky@amd.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/scatterlist.h>
#include <linux/crypto.h>
#include <crypto/algapi.h>
#include <crypto/aes.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 unit_size_map[] = {
	{
		.size	= 4096,
		.value	= CCP_XTS_AES_UNIT_SIZE_4096,
	},
	{
		.size	= 2048,
		.value	= CCP_XTS_AES_UNIT_SIZE_2048,
	},
	{
		.size	= 1024,
		.value	= CCP_XTS_AES_UNIT_SIZE_1024,
	},
	{
		.size	= 512,
		.value	= CCP_XTS_AES_UNIT_SIZE_512,
	},
	{
		.size	= 256,
		.value	= CCP_XTS_AES_UNIT_SIZE__LAST,
	},
	{
		.size	= 128,
		.value	= CCP_XTS_AES_UNIT_SIZE__LAST,
	},
	{
		.size	= 64,
		.value	= CCP_XTS_AES_UNIT_SIZE__LAST,
	},
	{
		.size	= 32,
		.value	= CCP_XTS_AES_UNIT_SIZE__LAST,
	},
	{
		.size	= 16,
		.value	= CCP_XTS_AES_UNIT_SIZE_16,
	},
	{
		.size	= 1,
		.value	= CCP_XTS_AES_UNIT_SIZE__LAST,
	},
};

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 ccp_ctx *ctx = crypto_tfm_ctx(crypto_ablkcipher_tfm(tfm));

	/* Only support 128-bit AES key with a 128-bit Tweak key,
	 * otherwise use the fallback
	 */
	switch (key_len) {
	case AES_KEYSIZE_128 * 2:
		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_ablkcipher_setkey(ctx->u.aes.tfm_ablkcipher, key,
					key_len);
}

static int ccp_aes_xts_crypt(struct ablkcipher_request *req,
			     unsigned int encrypt)
{
	struct crypto_tfm *tfm =
		crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
	struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
	struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
	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;

	unit_size = CCP_XTS_AES_UNIT_SIZE__LAST;
	if (req->nbytes <= unit_size_map[0].size) {
		for (unit = 0; unit < ARRAY_SIZE(unit_size_map); unit++) {
			if (!(req->nbytes & (unit_size_map[unit].size - 1))) {
				unit_size = unit_size_map[unit].value;
				break;
			}
		}
	}

	if ((unit_size == CCP_XTS_AES_UNIT_SIZE__LAST) ||
	    (ctx->u.aes.key_len != AES_KEYSIZE_128)) {
		/* Use the fallback to process the request for any
		 * unsupported unit sizes or key sizes
		 */
		ablkcipher_request_set_tfm(req, ctx->u.aes.tfm_ablkcipher);
		ret = (encrypt) ? crypto_ablkcipher_encrypt(req) :
				  crypto_ablkcipher_decrypt(req);
		ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));

		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.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_ablkcipher *fallback_tfm;

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

	fallback_tfm = crypto_alloc_ablkcipher(crypto_tfm_alg_name(tfm), 0,
					       CRYPTO_ALG_ASYNC |
					       CRYPTO_ALG_NEED_FALLBACK);
	if (IS_ERR(fallback_tfm)) {
		pr_warn("could not load fallback driver %s\n",
			crypto_tfm_alg_name(tfm));
		return PTR_ERR(fallback_tfm);
	}
	ctx->u.aes.tfm_ablkcipher = fallback_tfm;

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

	return 0;
}

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

	if (ctx->u.aes.tfm_ablkcipher)
		crypto_free_ablkcipher(ctx->u.aes.tfm_ablkcipher);
	ctx->u.aes.tfm_ablkcipher = NULL;
}

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
1d6b8a6f TL	1	/*
	2	* AMD Cryptographic Coprocessor (CCP) AES XTS crypto API support
	3	*
	4	* Copyright (C) 2013 Advanced Micro Devices, Inc.
	5	*
	6	* Author: Tom Lendacky <thomas.lendacky@amd.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*/
	12
	13	#include <linux/module.h>
	14	#include <linux/sched.h>
	15	#include <linux/delay.h>
	16	#include <linux/scatterlist.h>
	17	#include <linux/crypto.h>
	18	#include <crypto/algapi.h>
	19	#include <crypto/aes.h>
	20	#include <crypto/scatterwalk.h>
	21
	22	#include "ccp-crypto.h"
	23
1d6b8a6f TL	24	struct ccp_aes_xts_def {
	25	const char *name;
	26	const char *drv_name;
	27	};
	28
	29	static struct ccp_aes_xts_def aes_xts_algs[] = {
	30	{
	31	.name = "xts(aes)",
	32	.drv_name = "xts-aes-ccp",
	33	},
	34	};
	35
	36	struct ccp_unit_size_map {
	37	unsigned int size;
	38	u32 value;
	39	};
	40
	41	static struct ccp_unit_size_map unit_size_map[] = {
	42	{
	43	.size = 4096,
	44	.value = CCP_XTS_AES_UNIT_SIZE_4096,
	45	},
	46	{
	47	.size = 2048,
	48	.value = CCP_XTS_AES_UNIT_SIZE_2048,
	49	},
	50	{
	51	.size = 1024,
	52	.value = CCP_XTS_AES_UNIT_SIZE_1024,
	53	},
	54	{
	55	.size = 512,
	56	.value = CCP_XTS_AES_UNIT_SIZE_512,
	57	},
	58	{
	59	.size = 256,
	60	.value = CCP_XTS_AES_UNIT_SIZE__LAST,
	61	},
	62	{
	63	.size = 128,
	64	.value = CCP_XTS_AES_UNIT_SIZE__LAST,
	65	},
	66	{
	67	.size = 64,
	68	.value = CCP_XTS_AES_UNIT_SIZE__LAST,
	69	},
	70	{
	71	.size = 32,
	72	.value = CCP_XTS_AES_UNIT_SIZE__LAST,
	73	},
	74	{
	75	.size = 16,
	76	.value = CCP_XTS_AES_UNIT_SIZE_16,
	77	},
	78	{
	79	.size = 1,
	80	.value = CCP_XTS_AES_UNIT_SIZE__LAST,
	81	},
	82	};
	83
	84	static int ccp_aes_xts_complete(struct crypto_async_request *async_req, int ret)
	85	{
	86	struct ablkcipher_request *req = ablkcipher_request_cast(async_req);
	87	struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
88
89	if (ret)
90	return ret;
91
92	memcpy(req->info, rctx->iv, AES_BLOCK_SIZE);
93
94	return 0;
95	}
96
97	static int ccp_aes_xts_setkey(struct crypto_ablkcipher tfm, const u8 key,
98	unsigned int key_len)
99	{
100	struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ablkcipher_tfm(tfm));
101
102	/* Only support 128-bit AES key with a 128-bit Tweak key,
103	* otherwise use the fallback
104	*/
105	switch (key_len) {
106	case AES_KEYSIZE_128 * 2:
107	memcpy(ctx->u.aes.key, key, key_len);
108	break;
109	}
110	ctx->u.aes.key_len = key_len / 2;
111	sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);
112
113	return crypto_ablkcipher_setkey(ctx->u.aes.tfm_ablkcipher, key,
114	key_len);
115	}
116
117	static int ccp_aes_xts_crypt(struct ablkcipher_request *req,
118	unsigned int encrypt)
119	{
120	struct crypto_tfm *tfm =
121	crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
122	struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
123	struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
124	unsigned int unit;
ab6a11a7	125	u32 unit_size;
1d6b8a6f TL	126	int ret;
1d6b8a6f TL	127
369f3dab	128	if (!ctx->u.aes.key_len)
1d6b8a6f	129	return -EINVAL;
1d6b8a6f	130
369f3dab	131	if (req->nbytes & (AES_BLOCK_SIZE - 1))
1d6b8a6f	132	return -EINVAL;
1d6b8a6f	133
369f3dab	134	if (!req->info)
1d6b8a6f	135	return -EINVAL;
1d6b8a6f	136
ab6a11a7 TL	137	unit_size = CCP_XTS_AES_UNIT_SIZE__LAST;
	138	if (req->nbytes <= unit_size_map[0].size) {
	139	for (unit = 0; unit < ARRAY_SIZE(unit_size_map); unit++) {
	140	if (!(req->nbytes & (unit_size_map[unit].size - 1))) {
	141	unit_size = unit_size_map[unit].value;
	142	break;
	143	}
	144	}
	145	}
1d6b8a6f	146
ab6a11a7	147	if ((unit_size == CCP_XTS_AES_UNIT_SIZE__LAST) \|\|
1d6b8a6f TL	148	(ctx->u.aes.key_len != AES_KEYSIZE_128)) {
	149	/* Use the fallback to process the request for any
	150	* unsupported unit sizes or key sizes
	151	*/
	152	ablkcipher_request_set_tfm(req, ctx->u.aes.tfm_ablkcipher);
	153	ret = (encrypt) ? crypto_ablkcipher_encrypt(req) :
	154	crypto_ablkcipher_decrypt(req);
	155	ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
	156
	157	return ret;
	158	}
	159
	160	memcpy(rctx->iv, req->info, AES_BLOCK_SIZE);
	161	sg_init_one(&rctx->iv_sg, rctx->iv, AES_BLOCK_SIZE);
	162
	163	memset(&rctx->cmd, 0, sizeof(rctx->cmd));
	164	INIT_LIST_HEAD(&rctx->cmd.entry);
	165	rctx->cmd.engine = CCP_ENGINE_XTS_AES_128;
	166	rctx->cmd.u.xts.action = (encrypt) ? CCP_AES_ACTION_ENCRYPT
	167	: CCP_AES_ACTION_DECRYPT;
ab6a11a7	168	rctx->cmd.u.xts.unit_size = unit_size;
1d6b8a6f TL	169	rctx->cmd.u.xts.key = &ctx->u.aes.key_sg;
	170	rctx->cmd.u.xts.key_len = ctx->u.aes.key_len;
	171	rctx->cmd.u.xts.iv = &rctx->iv_sg;
	172	rctx->cmd.u.xts.iv_len = AES_BLOCK_SIZE;
	173	rctx->cmd.u.xts.src = req->src;
	174	rctx->cmd.u.xts.src_len = req->nbytes;
	175	rctx->cmd.u.xts.dst = req->dst;
	176
	177	ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
	178
	179	return ret;
	180	}
	181
	182	static int ccp_aes_xts_encrypt(struct ablkcipher_request *req)
	183	{
	184	return ccp_aes_xts_crypt(req, 1);
	185	}
	186
	187	static int ccp_aes_xts_decrypt(struct ablkcipher_request *req)
	188	{
	189	return ccp_aes_xts_crypt(req, 0);
	190	}
	191
	192	static int ccp_aes_xts_cra_init(struct crypto_tfm *tfm)
	193	{
	194	struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
	195	struct crypto_ablkcipher *fallback_tfm;
	196
	197	ctx->complete = ccp_aes_xts_complete;
	198	ctx->u.aes.key_len = 0;
	199
b4168a19	200	fallback_tfm = crypto_alloc_ablkcipher(crypto_tfm_alg_name(tfm), 0,
1d6b8a6f TL	201	CRYPTO_ALG_ASYNC \|
	202	CRYPTO_ALG_NEED_FALLBACK);
	203	if (IS_ERR(fallback_tfm)) {
	204	pr_warn("could not load fallback driver %s\n",
b4168a19	205	crypto_tfm_alg_name(tfm));
1d6b8a6f TL	206	return PTR_ERR(fallback_tfm);
	207	}
	208	ctx->u.aes.tfm_ablkcipher = fallback_tfm;
	209
	210	tfm->crt_ablkcipher.reqsize = sizeof(struct ccp_aes_req_ctx) +
	211	fallback_tfm->base.crt_ablkcipher.reqsize;
	212
	213	return 0;
	214	}
	215
	216	static void ccp_aes_xts_cra_exit(struct crypto_tfm *tfm)
	217	{
	218	struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
	219
	220	if (ctx->u.aes.tfm_ablkcipher)
	221	crypto_free_ablkcipher(ctx->u.aes.tfm_ablkcipher);
	222	ctx->u.aes.tfm_ablkcipher = NULL;
	223	}
	224
1d6b8a6f TL	225	static int ccp_register_aes_xts_alg(struct list_head *head,
	226	const struct ccp_aes_xts_def *def)
	227	{
	228	struct ccp_crypto_ablkcipher_alg *ccp_alg;
	229	struct crypto_alg *alg;
	230	int ret;
	231
	232	ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
	233	if (!ccp_alg)
	234	return -ENOMEM;
	235
	236	INIT_LIST_HEAD(&ccp_alg->entry);
	237
	238	alg = &ccp_alg->alg;
	239
	240	snprintf(alg->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
	241	snprintf(alg->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
	242	def->drv_name);
	243	alg->cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER \| CRYPTO_ALG_ASYNC \|
	244	CRYPTO_ALG_KERN_DRIVER_ONLY \|
	245	CRYPTO_ALG_NEED_FALLBACK;
	246	alg->cra_blocksize = AES_BLOCK_SIZE;
	247	alg->cra_ctxsize = sizeof(struct ccp_ctx);
	248	alg->cra_priority = CCP_CRA_PRIORITY;
	249	alg->cra_type = &crypto_ablkcipher_type;
	250	alg->cra_ablkcipher.setkey = ccp_aes_xts_setkey;
	251	alg->cra_ablkcipher.encrypt = ccp_aes_xts_encrypt;
	252	alg->cra_ablkcipher.decrypt = ccp_aes_xts_decrypt;
	253	alg->cra_ablkcipher.min_keysize = AES_MIN_KEY_SIZE * 2;
	254	alg->cra_ablkcipher.max_keysize = AES_MAX_KEY_SIZE * 2;
	255	alg->cra_ablkcipher.ivsize = AES_BLOCK_SIZE;
	256	alg->cra_init = ccp_aes_xts_cra_init;
	257	alg->cra_exit = ccp_aes_xts_cra_exit;
	258	alg->cra_module = THIS_MODULE;
	259
	260	ret = crypto_register_alg(alg);
	261	if (ret) {
	262	pr_err("%s ablkcipher algorithm registration error (%d)\n",
8db88467	263	alg->cra_name, ret);
1d6b8a6f TL	264	kfree(ccp_alg);
	265	return ret;
	266	}
	267
	268	list_add(&ccp_alg->entry, head);
	269
	270	return 0;
	271	}
	272
	273	int ccp_register_aes_xts_algs(struct list_head *head)
	274	{
	275	int i, ret;
	276
	277	for (i = 0; i < ARRAY_SIZE(aes_xts_algs); i++) {
	278	ret = ccp_register_aes_xts_alg(head, &aes_xts_algs[i]);
	279	if (ret)
	280	return ret;
	281	}
	282
	283	return 0;
	284	}