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
25static 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
40static 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
70static 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
117static int ccp_aes_encrypt(struct ablkcipher_request *req)
118{
119 return ccp_aes_crypt(req, true);
120}
121
122static int ccp_aes_decrypt(struct ablkcipher_request *req)
123{
124 return ccp_aes_crypt(req, false);
125}
126
127static 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
139static void ccp_aes_cra_exit(struct crypto_tfm *tfm)
140{
141}
142
143static 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
155static 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
169static 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
192static int ccp_aes_rfc3686_encrypt(struct ablkcipher_request *req)
193{
194 return ccp_aes_rfc3686_crypt(req, true);
195}
196
197static int ccp_aes_rfc3686_decrypt(struct ablkcipher_request *req)
198{
199 return ccp_aes_rfc3686_crypt(req, false);
200}
201
202static 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
214static void ccp_aes_rfc3686_cra_exit(struct crypto_tfm *tfm)
215{
216}
217
218static 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
239static 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
260struct 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
270static 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
327static 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
364int 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