xref: /linux/drivers/crypto/ccp/ccp-crypto-aes.c (revision 74ce1896c6c65b2f8cccbf59162d542988835835) 
1 /*
2  * AMD Cryptographic Coprocessor (CCP) AES crypto API support
3  *
4  * Copyright (C) 2013,2016 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/ctr.h>
21 #include <crypto/scatterwalk.h>
22 
23 #include "ccp-crypto.h"
24 
25 static int ccp_aes_complete(struct crypto_async_request *async_req, int ret)
26 {
27 	struct ablkcipher_request *req = ablkcipher_request_cast(async_req);
28 	struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
29 	struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
30 
31 	if (ret)
32 		return ret;
33 
34 	if (ctx->u.aes.mode != CCP_AES_MODE_ECB)
35 		memcpy(req->info, rctx->iv, AES_BLOCK_SIZE);
36 
37 	return 0;
38 }
39 
40 static int ccp_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
41 			  unsigned int key_len)
42 {
43 	struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ablkcipher_tfm(tfm));
44 	struct ccp_crypto_ablkcipher_alg *alg =
45 		ccp_crypto_ablkcipher_alg(crypto_ablkcipher_tfm(tfm));
46 
47 	switch (key_len) {
48 	case AES_KEYSIZE_128:
49 		ctx->u.aes.type = CCP_AES_TYPE_128;
50 		break;
51 	case AES_KEYSIZE_192:
52 		ctx->u.aes.type = CCP_AES_TYPE_192;
53 		break;
54 	case AES_KEYSIZE_256:
55 		ctx->u.aes.type = CCP_AES_TYPE_256;
56 		break;
57 	default:
58 		crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
59 		return -EINVAL;
60 	}
61 	ctx->u.aes.mode = alg->mode;
62 	ctx->u.aes.key_len = key_len;
63 
64 	memcpy(ctx->u.aes.key, key, key_len);
65 	sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);
66 
67 	return 0;
68 }
69 
70 static int ccp_aes_crypt(struct ablkcipher_request *req, bool encrypt)
71 {
72 	struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
73 	struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
74 	struct scatterlist *iv_sg = NULL;
75 	unsigned int iv_len = 0;
76 	int ret;
77 
78 	if (!ctx->u.aes.key_len)
79 		return -EINVAL;
80 
81 	if (((ctx->u.aes.mode == CCP_AES_MODE_ECB) ||
82 	     (ctx->u.aes.mode == CCP_AES_MODE_CBC) ||
83 	     (ctx->u.aes.mode == CCP_AES_MODE_CFB)) &&
84 	    (req->nbytes & (AES_BLOCK_SIZE - 1)))
85 		return -EINVAL;
86 
87 	if (ctx->u.aes.mode != CCP_AES_MODE_ECB) {
88 		if (!req->info)
89 			return -EINVAL;
90 
91 		memcpy(rctx->iv, req->info, AES_BLOCK_SIZE);
92 		iv_sg = &rctx->iv_sg;
93 		iv_len = AES_BLOCK_SIZE;
94 		sg_init_one(iv_sg, rctx->iv, iv_len);
95 	}
96 
97 	memset(&rctx->cmd, 0, sizeof(rctx->cmd));
98 	INIT_LIST_HEAD(&rctx->cmd.entry);
99 	rctx->cmd.engine = CCP_ENGINE_AES;
100 	rctx->cmd.u.aes.type = ctx->u.aes.type;
101 	rctx->cmd.u.aes.mode = ctx->u.aes.mode;
102 	rctx->cmd.u.aes.action =
103 		(encrypt) ? CCP_AES_ACTION_ENCRYPT : CCP_AES_ACTION_DECRYPT;
104 	rctx->cmd.u.aes.key = &ctx->u.aes.key_sg;
105 	rctx->cmd.u.aes.key_len = ctx->u.aes.key_len;
106 	rctx->cmd.u.aes.iv = iv_sg;
107 	rctx->cmd.u.aes.iv_len = iv_len;
108 	rctx->cmd.u.aes.src = req->src;
109 	rctx->cmd.u.aes.src_len = req->nbytes;
110 	rctx->cmd.u.aes.dst = req->dst;
111 
112 	ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
113 
114 	return ret;
115 }
116 
117 static int ccp_aes_encrypt(struct ablkcipher_request *req)
118 {
119 	return ccp_aes_crypt(req, true);
120 }
121 
122 static int ccp_aes_decrypt(struct ablkcipher_request *req)
123 {
124 	return ccp_aes_crypt(req, false);
125 }
126 
127 static int ccp_aes_cra_init(struct crypto_tfm *tfm)
128 {
129 	struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
130 
131 	ctx->complete = ccp_aes_complete;
132 	ctx->u.aes.key_len = 0;
133 
134 	tfm->crt_ablkcipher.reqsize = sizeof(struct ccp_aes_req_ctx);
135 
136 	return 0;
137 }
138 
139 static void ccp_aes_cra_exit(struct crypto_tfm *tfm)
140 {
141 }
142 
143 static int ccp_aes_rfc3686_complete(struct crypto_async_request *async_req,
144 				    int ret)
145 {
146 	struct ablkcipher_request *req = ablkcipher_request_cast(async_req);
147 	struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
148 
149 	/* Restore the original pointer */
150 	req->info = rctx->rfc3686_info;
151 
152 	return ccp_aes_complete(async_req, ret);
153 }
154 
155 static int ccp_aes_rfc3686_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
156 				  unsigned int key_len)
157 {
158 	struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ablkcipher_tfm(tfm));
159 
160 	if (key_len < CTR_RFC3686_NONCE_SIZE)
161 		return -EINVAL;
162 
163 	key_len -= CTR_RFC3686_NONCE_SIZE;
164 	memcpy(ctx->u.aes.nonce, key + key_len, CTR_RFC3686_NONCE_SIZE);
165 
166 	return ccp_aes_setkey(tfm, key, key_len);
167 }
168 
169 static int ccp_aes_rfc3686_crypt(struct ablkcipher_request *req, bool encrypt)
170 {
171 	struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
172 	struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
173 	u8 *iv;
174 
175 	/* Initialize the CTR block */
176 	iv = rctx->rfc3686_iv;
177 	memcpy(iv, ctx->u.aes.nonce, CTR_RFC3686_NONCE_SIZE);
178 
179 	iv += CTR_RFC3686_NONCE_SIZE;
180 	memcpy(iv, req->info, CTR_RFC3686_IV_SIZE);
181 
182 	iv += CTR_RFC3686_IV_SIZE;
183 	*(__be32 *)iv = cpu_to_be32(1);
184 
185 	/* Point to the new IV */
186 	rctx->rfc3686_info = req->info;
187 	req->info = rctx->rfc3686_iv;
188 
189 	return ccp_aes_crypt(req, encrypt);
190 }
191 
192 static int ccp_aes_rfc3686_encrypt(struct ablkcipher_request *req)
193 {
194 	return ccp_aes_rfc3686_crypt(req, true);
195 }
196 
197 static int ccp_aes_rfc3686_decrypt(struct ablkcipher_request *req)
198 {
199 	return ccp_aes_rfc3686_crypt(req, false);
200 }
201 
202 static int ccp_aes_rfc3686_cra_init(struct crypto_tfm *tfm)
203 {
204 	struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
205 
206 	ctx->complete = ccp_aes_rfc3686_complete;
207 	ctx->u.aes.key_len = 0;
208 
209 	tfm->crt_ablkcipher.reqsize = sizeof(struct ccp_aes_req_ctx);
210 
211 	return 0;
212 }
213 
214 static void ccp_aes_rfc3686_cra_exit(struct crypto_tfm *tfm)
215 {
216 }
217 
218 static struct crypto_alg ccp_aes_defaults = {
219 	.cra_flags	= CRYPTO_ALG_TYPE_ABLKCIPHER |
220 			  CRYPTO_ALG_ASYNC |
221 			  CRYPTO_ALG_KERN_DRIVER_ONLY |
222 			  CRYPTO_ALG_NEED_FALLBACK,
223 	.cra_blocksize	= AES_BLOCK_SIZE,
224 	.cra_ctxsize	= sizeof(struct ccp_ctx),
225 	.cra_priority	= CCP_CRA_PRIORITY,
226 	.cra_type	= &crypto_ablkcipher_type,
227 	.cra_init	= ccp_aes_cra_init,
228 	.cra_exit	= ccp_aes_cra_exit,
229 	.cra_module	= THIS_MODULE,
230 	.cra_ablkcipher	= {
231 		.setkey		= ccp_aes_setkey,
232 		.encrypt	= ccp_aes_encrypt,
233 		.decrypt	= ccp_aes_decrypt,
234 		.min_keysize	= AES_MIN_KEY_SIZE,
235 		.max_keysize	= AES_MAX_KEY_SIZE,
236 	},
237 };
238 
239 static struct crypto_alg ccp_aes_rfc3686_defaults = {
240 	.cra_flags	= CRYPTO_ALG_TYPE_ABLKCIPHER |
241 			   CRYPTO_ALG_ASYNC |
242 			   CRYPTO_ALG_KERN_DRIVER_ONLY |
243 			   CRYPTO_ALG_NEED_FALLBACK,
244 	.cra_blocksize	= CTR_RFC3686_BLOCK_SIZE,
245 	.cra_ctxsize	= sizeof(struct ccp_ctx),
246 	.cra_priority	= CCP_CRA_PRIORITY,
247 	.cra_type	= &crypto_ablkcipher_type,
248 	.cra_init	= ccp_aes_rfc3686_cra_init,
249 	.cra_exit	= ccp_aes_rfc3686_cra_exit,
250 	.cra_module	= THIS_MODULE,
251 	.cra_ablkcipher	= {
252 		.setkey		= ccp_aes_rfc3686_setkey,
253 		.encrypt	= ccp_aes_rfc3686_encrypt,
254 		.decrypt	= ccp_aes_rfc3686_decrypt,
255 		.min_keysize	= AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
256 		.max_keysize	= AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
257 	},
258 };
259 
260 struct ccp_aes_def {
261 	enum ccp_aes_mode mode;
262 	unsigned int version;
263 	const char *name;
264 	const char *driver_name;
265 	unsigned int blocksize;
266 	unsigned int ivsize;
267 	struct crypto_alg *alg_defaults;
268 };
269 
270 static struct ccp_aes_def aes_algs[] = {
271 	{
272 		.mode		= CCP_AES_MODE_ECB,
273 		.version	= CCP_VERSION(3, 0),
274 		.name		= "ecb(aes)",
275 		.driver_name	= "ecb-aes-ccp",
276 		.blocksize	= AES_BLOCK_SIZE,
277 		.ivsize		= 0,
278 		.alg_defaults	= &ccp_aes_defaults,
279 	},
280 	{
281 		.mode		= CCP_AES_MODE_CBC,
282 		.version	= CCP_VERSION(3, 0),
283 		.name		= "cbc(aes)",
284 		.driver_name	= "cbc-aes-ccp",
285 		.blocksize	= AES_BLOCK_SIZE,
286 		.ivsize		= AES_BLOCK_SIZE,
287 		.alg_defaults	= &ccp_aes_defaults,
288 	},
289 	{
290 		.mode		= CCP_AES_MODE_CFB,
291 		.version	= CCP_VERSION(3, 0),
292 		.name		= "cfb(aes)",
293 		.driver_name	= "cfb-aes-ccp",
294 		.blocksize	= AES_BLOCK_SIZE,
295 		.ivsize		= AES_BLOCK_SIZE,
296 		.alg_defaults	= &ccp_aes_defaults,
297 	},
298 	{
299 		.mode		= CCP_AES_MODE_OFB,
300 		.version	= CCP_VERSION(3, 0),
301 		.name		= "ofb(aes)",
302 		.driver_name	= "ofb-aes-ccp",
303 		.blocksize	= 1,
304 		.ivsize		= AES_BLOCK_SIZE,
305 		.alg_defaults	= &ccp_aes_defaults,
306 	},
307 	{
308 		.mode		= CCP_AES_MODE_CTR,
309 		.version	= CCP_VERSION(3, 0),
310 		.name		= "ctr(aes)",
311 		.driver_name	= "ctr-aes-ccp",
312 		.blocksize	= 1,
313 		.ivsize		= AES_BLOCK_SIZE,
314 		.alg_defaults	= &ccp_aes_defaults,
315 	},
316 	{
317 		.mode		= CCP_AES_MODE_CTR,
318 		.version	= CCP_VERSION(3, 0),
319 		.name		= "rfc3686(ctr(aes))",
320 		.driver_name	= "rfc3686-ctr-aes-ccp",
321 		.blocksize	= 1,
322 		.ivsize		= CTR_RFC3686_IV_SIZE,
323 		.alg_defaults	= &ccp_aes_rfc3686_defaults,
324 	},
325 };
326 
327 static int ccp_register_aes_alg(struct list_head *head,
328 				const struct ccp_aes_def *def)
329 {
330 	struct ccp_crypto_ablkcipher_alg *ccp_alg;
331 	struct crypto_alg *alg;
332 	int ret;
333 
334 	ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
335 	if (!ccp_alg)
336 		return -ENOMEM;
337 
338 	INIT_LIST_HEAD(&ccp_alg->entry);
339 
340 	ccp_alg->mode = def->mode;
341 
342 	/* Copy the defaults and override as necessary */
343 	alg = &ccp_alg->alg;
344 	*alg = *def->alg_defaults;
345 	snprintf(alg->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
346 	snprintf(alg->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
347 		 def->driver_name);
348 	alg->cra_blocksize = def->blocksize;
349 	alg->cra_ablkcipher.ivsize = def->ivsize;
350 
351 	ret = crypto_register_alg(alg);
352 	if (ret) {
353 		pr_err("%s ablkcipher algorithm registration error (%d)\n",
354 		       alg->cra_name, ret);
355 		kfree(ccp_alg);
356 		return ret;
357 	}
358 
359 	list_add(&ccp_alg->entry, head);
360 
361 	return 0;
362 }
363 
364 int ccp_register_aes_algs(struct list_head *head)
365 {
366 	int i, ret;
367 	unsigned int ccpversion = ccp_version();
368 
369 	for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
370 		if (aes_algs[i].version > ccpversion)
371 			continue;
372 		ret = ccp_register_aes_alg(head, &aes_algs[i]);
373 		if (ret)
374 			return ret;
375 	}
376 
377 	return 0;
378 }
379