1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * AMD Cryptographic Coprocessor (CCP) AES crypto API support
4 *
5 * Copyright (C) 2013-2019 Advanced Micro Devices, Inc.
6 *
7 * Author: Tom Lendacky <thomas.lendacky@amd.com>
8 */
9
10 #include <linux/module.h>
11 #include <linux/sched.h>
12 #include <linux/delay.h>
13 #include <linux/scatterlist.h>
14 #include <linux/crypto.h>
15 #include <crypto/algapi.h>
16 #include <crypto/aes.h>
17 #include <crypto/ctr.h>
18 #include <crypto/scatterwalk.h>
19
20 #include "ccp-crypto.h"
21
ccp_aes_complete(struct crypto_async_request * async_req,int ret)22 static int ccp_aes_complete(struct crypto_async_request *async_req, int ret)
23 {
24 struct skcipher_request *req = skcipher_request_cast(async_req);
25 struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(
26 crypto_skcipher_reqtfm(req));
27 struct ccp_aes_req_ctx *rctx = skcipher_request_ctx_dma(req);
28
29 if (ret)
30 return ret;
31
32 if (ctx->u.aes.mode != CCP_AES_MODE_ECB)
33 memcpy(req->iv, rctx->iv, AES_BLOCK_SIZE);
34
35 return 0;
36 }
37
ccp_aes_setkey(struct crypto_skcipher * tfm,const u8 * key,unsigned int key_len)38 static int ccp_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
39 unsigned int key_len)
40 {
41 struct ccp_crypto_skcipher_alg *alg = ccp_crypto_skcipher_alg(tfm);
42 struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
43
44 switch (key_len) {
45 case AES_KEYSIZE_128:
46 ctx->u.aes.type = CCP_AES_TYPE_128;
47 break;
48 case AES_KEYSIZE_192:
49 ctx->u.aes.type = CCP_AES_TYPE_192;
50 break;
51 case AES_KEYSIZE_256:
52 ctx->u.aes.type = CCP_AES_TYPE_256;
53 break;
54 default:
55 return -EINVAL;
56 }
57 ctx->u.aes.mode = alg->mode;
58 ctx->u.aes.key_len = key_len;
59
60 memcpy(ctx->u.aes.key, key, key_len);
61 sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);
62
63 return 0;
64 }
65
ccp_aes_crypt(struct skcipher_request * req,bool encrypt)66 static int ccp_aes_crypt(struct skcipher_request *req, bool encrypt)
67 {
68 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
69 struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
70 struct ccp_aes_req_ctx *rctx = skcipher_request_ctx_dma(req);
71 struct scatterlist *iv_sg = NULL;
72 unsigned int iv_len = 0;
73
74 if (!ctx->u.aes.key_len)
75 return -EINVAL;
76
77 if (((ctx->u.aes.mode == CCP_AES_MODE_ECB) ||
78 (ctx->u.aes.mode == CCP_AES_MODE_CBC)) &&
79 (req->cryptlen & (AES_BLOCK_SIZE - 1)))
80 return -EINVAL;
81
82 if (ctx->u.aes.mode != CCP_AES_MODE_ECB) {
83 if (!req->iv)
84 return -EINVAL;
85
86 memcpy(rctx->iv, req->iv, AES_BLOCK_SIZE);
87 iv_sg = &rctx->iv_sg;
88 iv_len = AES_BLOCK_SIZE;
89 sg_init_one(iv_sg, rctx->iv, iv_len);
90 }
91
92 memset(&rctx->cmd, 0, sizeof(rctx->cmd));
93 INIT_LIST_HEAD(&rctx->cmd.entry);
94 rctx->cmd.engine = CCP_ENGINE_AES;
95 rctx->cmd.u.aes.type = ctx->u.aes.type;
96 rctx->cmd.u.aes.mode = ctx->u.aes.mode;
97 rctx->cmd.u.aes.action =
98 (encrypt) ? CCP_AES_ACTION_ENCRYPT : CCP_AES_ACTION_DECRYPT;
99 rctx->cmd.u.aes.key = &ctx->u.aes.key_sg;
100 rctx->cmd.u.aes.key_len = ctx->u.aes.key_len;
101 rctx->cmd.u.aes.iv = iv_sg;
102 rctx->cmd.u.aes.iv_len = iv_len;
103 rctx->cmd.u.aes.src = req->src;
104 rctx->cmd.u.aes.src_len = req->cryptlen;
105 rctx->cmd.u.aes.dst = req->dst;
106
107 return ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
108 }
109
ccp_aes_encrypt(struct skcipher_request * req)110 static int ccp_aes_encrypt(struct skcipher_request *req)
111 {
112 return ccp_aes_crypt(req, true);
113 }
114
ccp_aes_decrypt(struct skcipher_request * req)115 static int ccp_aes_decrypt(struct skcipher_request *req)
116 {
117 return ccp_aes_crypt(req, false);
118 }
119
ccp_aes_init_tfm(struct crypto_skcipher * tfm)120 static int ccp_aes_init_tfm(struct crypto_skcipher *tfm)
121 {
122 struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
123
124 ctx->complete = ccp_aes_complete;
125 ctx->u.aes.key_len = 0;
126
127 crypto_skcipher_set_reqsize(tfm, sizeof(struct ccp_aes_req_ctx));
128
129 return 0;
130 }
131
ccp_aes_rfc3686_complete(struct crypto_async_request * async_req,int ret)132 static int ccp_aes_rfc3686_complete(struct crypto_async_request *async_req,
133 int ret)
134 {
135 struct skcipher_request *req = skcipher_request_cast(async_req);
136 struct ccp_aes_req_ctx *rctx = skcipher_request_ctx_dma(req);
137
138 /* Restore the original pointer */
139 req->iv = rctx->rfc3686_info;
140
141 return ccp_aes_complete(async_req, ret);
142 }
143
ccp_aes_rfc3686_setkey(struct crypto_skcipher * tfm,const u8 * key,unsigned int key_len)144 static int ccp_aes_rfc3686_setkey(struct crypto_skcipher *tfm, const u8 *key,
145 unsigned int key_len)
146 {
147 struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
148
149 if (key_len < CTR_RFC3686_NONCE_SIZE)
150 return -EINVAL;
151
152 key_len -= CTR_RFC3686_NONCE_SIZE;
153 memcpy(ctx->u.aes.nonce, key + key_len, CTR_RFC3686_NONCE_SIZE);
154
155 return ccp_aes_setkey(tfm, key, key_len);
156 }
157
ccp_aes_rfc3686_crypt(struct skcipher_request * req,bool encrypt)158 static int ccp_aes_rfc3686_crypt(struct skcipher_request *req, bool encrypt)
159 {
160 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
161 struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
162 struct ccp_aes_req_ctx *rctx = skcipher_request_ctx_dma(req);
163 u8 *iv;
164
165 /* Initialize the CTR block */
166 iv = rctx->rfc3686_iv;
167 memcpy(iv, ctx->u.aes.nonce, CTR_RFC3686_NONCE_SIZE);
168
169 iv += CTR_RFC3686_NONCE_SIZE;
170 memcpy(iv, req->iv, CTR_RFC3686_IV_SIZE);
171
172 iv += CTR_RFC3686_IV_SIZE;
173 *(__be32 *)iv = cpu_to_be32(1);
174
175 /* Point to the new IV */
176 rctx->rfc3686_info = req->iv;
177 req->iv = rctx->rfc3686_iv;
178
179 return ccp_aes_crypt(req, encrypt);
180 }
181
ccp_aes_rfc3686_encrypt(struct skcipher_request * req)182 static int ccp_aes_rfc3686_encrypt(struct skcipher_request *req)
183 {
184 return ccp_aes_rfc3686_crypt(req, true);
185 }
186
ccp_aes_rfc3686_decrypt(struct skcipher_request * req)187 static int ccp_aes_rfc3686_decrypt(struct skcipher_request *req)
188 {
189 return ccp_aes_rfc3686_crypt(req, false);
190 }
191
ccp_aes_rfc3686_init_tfm(struct crypto_skcipher * tfm)192 static int ccp_aes_rfc3686_init_tfm(struct crypto_skcipher *tfm)
193 {
194 struct ccp_ctx *ctx = crypto_skcipher_ctx_dma(tfm);
195
196 ctx->complete = ccp_aes_rfc3686_complete;
197 ctx->u.aes.key_len = 0;
198
199 crypto_skcipher_set_reqsize_dma(tfm, sizeof(struct ccp_aes_req_ctx));
200
201 return 0;
202 }
203
204 static const struct skcipher_alg ccp_aes_defaults = {
205 .setkey = ccp_aes_setkey,
206 .encrypt = ccp_aes_encrypt,
207 .decrypt = ccp_aes_decrypt,
208 .min_keysize = AES_MIN_KEY_SIZE,
209 .max_keysize = AES_MAX_KEY_SIZE,
210 .init = ccp_aes_init_tfm,
211
212 .base.cra_flags = CRYPTO_ALG_ASYNC |
213 CRYPTO_ALG_ALLOCATES_MEMORY |
214 CRYPTO_ALG_KERN_DRIVER_ONLY |
215 CRYPTO_ALG_NEED_FALLBACK,
216 .base.cra_blocksize = AES_BLOCK_SIZE,
217 .base.cra_ctxsize = sizeof(struct ccp_ctx) + CRYPTO_DMA_PADDING,
218 .base.cra_priority = CCP_CRA_PRIORITY,
219 .base.cra_module = THIS_MODULE,
220 };
221
222 static const struct skcipher_alg ccp_aes_rfc3686_defaults = {
223 .setkey = ccp_aes_rfc3686_setkey,
224 .encrypt = ccp_aes_rfc3686_encrypt,
225 .decrypt = ccp_aes_rfc3686_decrypt,
226 .min_keysize = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
227 .max_keysize = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
228 .init = ccp_aes_rfc3686_init_tfm,
229
230 .base.cra_flags = CRYPTO_ALG_ASYNC |
231 CRYPTO_ALG_ALLOCATES_MEMORY |
232 CRYPTO_ALG_KERN_DRIVER_ONLY |
233 CRYPTO_ALG_NEED_FALLBACK,
234 .base.cra_blocksize = CTR_RFC3686_BLOCK_SIZE,
235 .base.cra_ctxsize = sizeof(struct ccp_ctx) + CRYPTO_DMA_PADDING,
236 .base.cra_priority = CCP_CRA_PRIORITY,
237 .base.cra_module = THIS_MODULE,
238 };
239
240 struct ccp_aes_def {
241 enum ccp_aes_mode mode;
242 unsigned int version;
243 const char *name;
244 const char *driver_name;
245 unsigned int blocksize;
246 unsigned int ivsize;
247 const struct skcipher_alg *alg_defaults;
248 };
249
250 static struct ccp_aes_def aes_algs[] = {
251 {
252 .mode = CCP_AES_MODE_ECB,
253 .version = CCP_VERSION(3, 0),
254 .name = "ecb(aes)",
255 .driver_name = "ecb-aes-ccp",
256 .blocksize = AES_BLOCK_SIZE,
257 .ivsize = 0,
258 .alg_defaults = &ccp_aes_defaults,
259 },
260 {
261 .mode = CCP_AES_MODE_CBC,
262 .version = CCP_VERSION(3, 0),
263 .name = "cbc(aes)",
264 .driver_name = "cbc-aes-ccp",
265 .blocksize = AES_BLOCK_SIZE,
266 .ivsize = AES_BLOCK_SIZE,
267 .alg_defaults = &ccp_aes_defaults,
268 },
269 {
270 .mode = CCP_AES_MODE_CTR,
271 .version = CCP_VERSION(3, 0),
272 .name = "ctr(aes)",
273 .driver_name = "ctr-aes-ccp",
274 .blocksize = 1,
275 .ivsize = AES_BLOCK_SIZE,
276 .alg_defaults = &ccp_aes_defaults,
277 },
278 {
279 .mode = CCP_AES_MODE_CTR,
280 .version = CCP_VERSION(3, 0),
281 .name = "rfc3686(ctr(aes))",
282 .driver_name = "rfc3686-ctr-aes-ccp",
283 .blocksize = 1,
284 .ivsize = CTR_RFC3686_IV_SIZE,
285 .alg_defaults = &ccp_aes_rfc3686_defaults,
286 },
287 };
288
ccp_register_aes_alg(struct list_head * head,const struct ccp_aes_def * def)289 static int ccp_register_aes_alg(struct list_head *head,
290 const struct ccp_aes_def *def)
291 {
292 struct ccp_crypto_skcipher_alg *ccp_alg;
293 struct skcipher_alg *alg;
294 int ret;
295
296 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
297 if (!ccp_alg)
298 return -ENOMEM;
299
300 INIT_LIST_HEAD(&ccp_alg->entry);
301
302 ccp_alg->mode = def->mode;
303
304 /* Copy the defaults and override as necessary */
305 alg = &ccp_alg->alg;
306 *alg = *def->alg_defaults;
307 snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
308 snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
309 def->driver_name);
310 alg->base.cra_blocksize = def->blocksize;
311 alg->ivsize = def->ivsize;
312
313 ret = crypto_register_skcipher(alg);
314 if (ret) {
315 pr_err("%s skcipher algorithm registration error (%d)\n",
316 alg->base.cra_name, ret);
317 kfree(ccp_alg);
318 return ret;
319 }
320
321 list_add(&ccp_alg->entry, head);
322
323 return 0;
324 }
325
ccp_register_aes_algs(struct list_head * head)326 int ccp_register_aes_algs(struct list_head *head)
327 {
328 int i, ret;
329 unsigned int ccpversion = ccp_version();
330
331 for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
332 if (aes_algs[i].version > ccpversion)
333 continue;
334 ret = ccp_register_aes_alg(head, &aes_algs[i]);
335 if (ret)
336 return ret;
337 }
338
339 return 0;
340 }
341