1 /*
2 * AMD Cryptographic Coprocessor (CCP) SHA 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/hash.h>
20 #include <crypto/internal/hash.h>
21 #include <crypto/sha.h>
22 #include <crypto/scatterwalk.h>
23
24 #include "ccp-crypto.h"
25
ccp_sha_complete(struct crypto_async_request * async_req,int ret)26 static int ccp_sha_complete(struct crypto_async_request *async_req, int ret)
27 {
28 struct ahash_request *req = ahash_request_cast(async_req);
29 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
30 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
31 unsigned int digest_size = crypto_ahash_digestsize(tfm);
32
33 if (ret)
34 goto e_free;
35
36 if (rctx->hash_rem) {
37 /* Save remaining data to buffer */
38 unsigned int offset = rctx->nbytes - rctx->hash_rem;
39
40 scatterwalk_map_and_copy(rctx->buf, rctx->src,
41 offset, rctx->hash_rem, 0);
42 rctx->buf_count = rctx->hash_rem;
43 } else {
44 rctx->buf_count = 0;
45 }
46
47 /* Update result area if supplied */
48 if (req->result)
49 memcpy(req->result, rctx->ctx, digest_size);
50
51 e_free:
52 sg_free_table(&rctx->data_sg);
53
54 return ret;
55 }
56
ccp_do_sha_update(struct ahash_request * req,unsigned int nbytes,unsigned int final)57 static int ccp_do_sha_update(struct ahash_request *req, unsigned int nbytes,
58 unsigned int final)
59 {
60 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
61 struct ccp_ctx *ctx = crypto_ahash_ctx(tfm);
62 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
63 struct scatterlist *sg;
64 unsigned int block_size =
65 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
66 unsigned int sg_count;
67 gfp_t gfp;
68 u64 len;
69 int ret;
70
71 len = (u64)rctx->buf_count + (u64)nbytes;
72
73 if (!final && (len <= block_size)) {
74 scatterwalk_map_and_copy(rctx->buf + rctx->buf_count, req->src,
75 0, nbytes, 0);
76 rctx->buf_count += nbytes;
77
78 return 0;
79 }
80
81 rctx->src = req->src;
82 rctx->nbytes = nbytes;
83
84 rctx->final = final;
85 rctx->hash_rem = final ? 0 : len & (block_size - 1);
86 rctx->hash_cnt = len - rctx->hash_rem;
87 if (!final && !rctx->hash_rem) {
88 /* CCP can't do zero length final, so keep some data around */
89 rctx->hash_cnt -= block_size;
90 rctx->hash_rem = block_size;
91 }
92
93 /* Initialize the context scatterlist */
94 sg_init_one(&rctx->ctx_sg, rctx->ctx, sizeof(rctx->ctx));
95
96 sg = NULL;
97 if (rctx->buf_count && nbytes) {
98 /* Build the data scatterlist table - allocate enough entries
99 * for both data pieces (buffer and input data)
100 */
101 gfp = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
102 GFP_KERNEL : GFP_ATOMIC;
103 sg_count = sg_nents(req->src) + 1;
104 ret = sg_alloc_table(&rctx->data_sg, sg_count, gfp);
105 if (ret)
106 return ret;
107
108 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count);
109 sg = ccp_crypto_sg_table_add(&rctx->data_sg, &rctx->buf_sg);
110 if (!sg) {
111 ret = -EINVAL;
112 goto e_free;
113 }
114 sg = ccp_crypto_sg_table_add(&rctx->data_sg, req->src);
115 if (!sg) {
116 ret = -EINVAL;
117 goto e_free;
118 }
119 sg_mark_end(sg);
120
121 sg = rctx->data_sg.sgl;
122 } else if (rctx->buf_count) {
123 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count);
124
125 sg = &rctx->buf_sg;
126 } else if (nbytes) {
127 sg = req->src;
128 }
129
130 rctx->msg_bits += (rctx->hash_cnt << 3); /* Total in bits */
131
132 memset(&rctx->cmd, 0, sizeof(rctx->cmd));
133 INIT_LIST_HEAD(&rctx->cmd.entry);
134 rctx->cmd.engine = CCP_ENGINE_SHA;
135 rctx->cmd.u.sha.type = rctx->type;
136 rctx->cmd.u.sha.ctx = &rctx->ctx_sg;
137 rctx->cmd.u.sha.ctx_len = sizeof(rctx->ctx);
138 rctx->cmd.u.sha.src = sg;
139 rctx->cmd.u.sha.src_len = rctx->hash_cnt;
140 rctx->cmd.u.sha.opad = ctx->u.sha.key_len ?
141 &ctx->u.sha.opad_sg : NULL;
142 rctx->cmd.u.sha.opad_len = ctx->u.sha.key_len ?
143 ctx->u.sha.opad_count : 0;
144 rctx->cmd.u.sha.first = rctx->first;
145 rctx->cmd.u.sha.final = rctx->final;
146 rctx->cmd.u.sha.msg_bits = rctx->msg_bits;
147
148 rctx->first = 0;
149
150 ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
151
152 return ret;
153
154 e_free:
155 sg_free_table(&rctx->data_sg);
156
157 return ret;
158 }
159
ccp_sha_init(struct ahash_request * req)160 static int ccp_sha_init(struct ahash_request *req)
161 {
162 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
163 struct ccp_ctx *ctx = crypto_ahash_ctx(tfm);
164 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
165 struct ccp_crypto_ahash_alg *alg =
166 ccp_crypto_ahash_alg(crypto_ahash_tfm(tfm));
167 unsigned int block_size =
168 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
169
170 memset(rctx, 0, sizeof(*rctx));
171
172 rctx->type = alg->type;
173 rctx->first = 1;
174
175 if (ctx->u.sha.key_len) {
176 /* Buffer the HMAC key for first update */
177 memcpy(rctx->buf, ctx->u.sha.ipad, block_size);
178 rctx->buf_count = block_size;
179 }
180
181 return 0;
182 }
183
ccp_sha_update(struct ahash_request * req)184 static int ccp_sha_update(struct ahash_request *req)
185 {
186 return ccp_do_sha_update(req, req->nbytes, 0);
187 }
188
ccp_sha_final(struct ahash_request * req)189 static int ccp_sha_final(struct ahash_request *req)
190 {
191 return ccp_do_sha_update(req, 0, 1);
192 }
193
ccp_sha_finup(struct ahash_request * req)194 static int ccp_sha_finup(struct ahash_request *req)
195 {
196 return ccp_do_sha_update(req, req->nbytes, 1);
197 }
198
ccp_sha_digest(struct ahash_request * req)199 static int ccp_sha_digest(struct ahash_request *req)
200 {
201 int ret;
202
203 ret = ccp_sha_init(req);
204 if (ret)
205 return ret;
206
207 return ccp_sha_finup(req);
208 }
209
ccp_sha_export(struct ahash_request * req,void * out)210 static int ccp_sha_export(struct ahash_request *req, void *out)
211 {
212 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
213 struct ccp_sha_exp_ctx state;
214
215 /* Don't let anything leak to 'out' */
216 memset(&state, 0, sizeof(state));
217
218 state.type = rctx->type;
219 state.msg_bits = rctx->msg_bits;
220 state.first = rctx->first;
221 memcpy(state.ctx, rctx->ctx, sizeof(state.ctx));
222 state.buf_count = rctx->buf_count;
223 memcpy(state.buf, rctx->buf, sizeof(state.buf));
224
225 /* 'out' may not be aligned so memcpy from local variable */
226 memcpy(out, &state, sizeof(state));
227
228 return 0;
229 }
230
ccp_sha_import(struct ahash_request * req,const void * in)231 static int ccp_sha_import(struct ahash_request *req, const void *in)
232 {
233 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
234 struct ccp_sha_exp_ctx state;
235
236 /* 'in' may not be aligned so memcpy to local variable */
237 memcpy(&state, in, sizeof(state));
238
239 memset(rctx, 0, sizeof(*rctx));
240 rctx->type = state.type;
241 rctx->msg_bits = state.msg_bits;
242 rctx->first = state.first;
243 memcpy(rctx->ctx, state.ctx, sizeof(rctx->ctx));
244 rctx->buf_count = state.buf_count;
245 memcpy(rctx->buf, state.buf, sizeof(rctx->buf));
246
247 return 0;
248 }
249
ccp_sha_setkey(struct crypto_ahash * tfm,const u8 * key,unsigned int key_len)250 static int ccp_sha_setkey(struct crypto_ahash *tfm, const u8 *key,
251 unsigned int key_len)
252 {
253 struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm));
254 struct crypto_shash *shash = ctx->u.sha.hmac_tfm;
255
256 SHASH_DESC_ON_STACK(sdesc, shash);
257
258 unsigned int block_size = crypto_shash_blocksize(shash);
259 unsigned int digest_size = crypto_shash_digestsize(shash);
260 int i, ret;
261
262 /* Set to zero until complete */
263 ctx->u.sha.key_len = 0;
264
265 /* Clear key area to provide zero padding for keys smaller
266 * than the block size
267 */
268 memset(ctx->u.sha.key, 0, sizeof(ctx->u.sha.key));
269
270 if (key_len > block_size) {
271 /* Must hash the input key */
272 sdesc->tfm = shash;
273 sdesc->flags = crypto_ahash_get_flags(tfm) &
274 CRYPTO_TFM_REQ_MAY_SLEEP;
275
276 ret = crypto_shash_digest(sdesc, key, key_len,
277 ctx->u.sha.key);
278 if (ret) {
279 crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
280 return -EINVAL;
281 }
282
283 key_len = digest_size;
284 } else {
285 memcpy(ctx->u.sha.key, key, key_len);
286 }
287
288 for (i = 0; i < block_size; i++) {
289 ctx->u.sha.ipad[i] = ctx->u.sha.key[i] ^ 0x36;
290 ctx->u.sha.opad[i] = ctx->u.sha.key[i] ^ 0x5c;
291 }
292
293 sg_init_one(&ctx->u.sha.opad_sg, ctx->u.sha.opad, block_size);
294 ctx->u.sha.opad_count = block_size;
295
296 ctx->u.sha.key_len = key_len;
297
298 return 0;
299 }
300
ccp_sha_cra_init(struct crypto_tfm * tfm)301 static int ccp_sha_cra_init(struct crypto_tfm *tfm)
302 {
303 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
304 struct crypto_ahash *ahash = __crypto_ahash_cast(tfm);
305
306 ctx->complete = ccp_sha_complete;
307 ctx->u.sha.key_len = 0;
308
309 crypto_ahash_set_reqsize(ahash, sizeof(struct ccp_sha_req_ctx));
310
311 return 0;
312 }
313
ccp_sha_cra_exit(struct crypto_tfm * tfm)314 static void ccp_sha_cra_exit(struct crypto_tfm *tfm)
315 {
316 }
317
ccp_hmac_sha_cra_init(struct crypto_tfm * tfm)318 static int ccp_hmac_sha_cra_init(struct crypto_tfm *tfm)
319 {
320 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
321 struct ccp_crypto_ahash_alg *alg = ccp_crypto_ahash_alg(tfm);
322 struct crypto_shash *hmac_tfm;
323
324 hmac_tfm = crypto_alloc_shash(alg->child_alg, 0, 0);
325 if (IS_ERR(hmac_tfm)) {
326 pr_warn("could not load driver %s need for HMAC support\n",
327 alg->child_alg);
328 return PTR_ERR(hmac_tfm);
329 }
330
331 ctx->u.sha.hmac_tfm = hmac_tfm;
332
333 return ccp_sha_cra_init(tfm);
334 }
335
ccp_hmac_sha_cra_exit(struct crypto_tfm * tfm)336 static void ccp_hmac_sha_cra_exit(struct crypto_tfm *tfm)
337 {
338 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
339
340 if (ctx->u.sha.hmac_tfm)
341 crypto_free_shash(ctx->u.sha.hmac_tfm);
342
343 ccp_sha_cra_exit(tfm);
344 }
345
346 struct ccp_sha_def {
347 const char *name;
348 const char *drv_name;
349 enum ccp_sha_type type;
350 u32 digest_size;
351 u32 block_size;
352 };
353
354 static struct ccp_sha_def sha_algs[] = {
355 {
356 .name = "sha1",
357 .drv_name = "sha1-ccp",
358 .type = CCP_SHA_TYPE_1,
359 .digest_size = SHA1_DIGEST_SIZE,
360 .block_size = SHA1_BLOCK_SIZE,
361 },
362 {
363 .name = "sha224",
364 .drv_name = "sha224-ccp",
365 .type = CCP_SHA_TYPE_224,
366 .digest_size = SHA224_DIGEST_SIZE,
367 .block_size = SHA224_BLOCK_SIZE,
368 },
369 {
370 .name = "sha256",
371 .drv_name = "sha256-ccp",
372 .type = CCP_SHA_TYPE_256,
373 .digest_size = SHA256_DIGEST_SIZE,
374 .block_size = SHA256_BLOCK_SIZE,
375 },
376 };
377
ccp_register_hmac_alg(struct list_head * head,const struct ccp_sha_def * def,const struct ccp_crypto_ahash_alg * base_alg)378 static int ccp_register_hmac_alg(struct list_head *head,
379 const struct ccp_sha_def *def,
380 const struct ccp_crypto_ahash_alg *base_alg)
381 {
382 struct ccp_crypto_ahash_alg *ccp_alg;
383 struct ahash_alg *alg;
384 struct hash_alg_common *halg;
385 struct crypto_alg *base;
386 int ret;
387
388 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
389 if (!ccp_alg)
390 return -ENOMEM;
391
392 /* Copy the base algorithm and only change what's necessary */
393 *ccp_alg = *base_alg;
394 INIT_LIST_HEAD(&ccp_alg->entry);
395
396 strncpy(ccp_alg->child_alg, def->name, CRYPTO_MAX_ALG_NAME);
397
398 alg = &ccp_alg->alg;
399 alg->setkey = ccp_sha_setkey;
400
401 halg = &alg->halg;
402
403 base = &halg->base;
404 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)", def->name);
405 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "hmac-%s",
406 def->drv_name);
407 base->cra_init = ccp_hmac_sha_cra_init;
408 base->cra_exit = ccp_hmac_sha_cra_exit;
409
410 ret = crypto_register_ahash(alg);
411 if (ret) {
412 pr_err("%s ahash algorithm registration error (%d)\n",
413 base->cra_name, ret);
414 kfree(ccp_alg);
415 return ret;
416 }
417
418 list_add(&ccp_alg->entry, head);
419
420 return ret;
421 }
422
ccp_register_sha_alg(struct list_head * head,const struct ccp_sha_def * def)423 static int ccp_register_sha_alg(struct list_head *head,
424 const struct ccp_sha_def *def)
425 {
426 struct ccp_crypto_ahash_alg *ccp_alg;
427 struct ahash_alg *alg;
428 struct hash_alg_common *halg;
429 struct crypto_alg *base;
430 int ret;
431
432 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
433 if (!ccp_alg)
434 return -ENOMEM;
435
436 INIT_LIST_HEAD(&ccp_alg->entry);
437
438 ccp_alg->type = def->type;
439
440 alg = &ccp_alg->alg;
441 alg->init = ccp_sha_init;
442 alg->update = ccp_sha_update;
443 alg->final = ccp_sha_final;
444 alg->finup = ccp_sha_finup;
445 alg->digest = ccp_sha_digest;
446 alg->export = ccp_sha_export;
447 alg->import = ccp_sha_import;
448
449 halg = &alg->halg;
450 halg->digestsize = def->digest_size;
451 halg->statesize = sizeof(struct ccp_sha_exp_ctx);
452
453 base = &halg->base;
454 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
455 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
456 def->drv_name);
457 base->cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC |
458 CRYPTO_ALG_KERN_DRIVER_ONLY |
459 CRYPTO_ALG_NEED_FALLBACK;
460 base->cra_blocksize = def->block_size;
461 base->cra_ctxsize = sizeof(struct ccp_ctx);
462 base->cra_priority = CCP_CRA_PRIORITY;
463 base->cra_type = &crypto_ahash_type;
464 base->cra_init = ccp_sha_cra_init;
465 base->cra_exit = ccp_sha_cra_exit;
466 base->cra_module = THIS_MODULE;
467
468 ret = crypto_register_ahash(alg);
469 if (ret) {
470 pr_err("%s ahash algorithm registration error (%d)\n",
471 base->cra_name, ret);
472 kfree(ccp_alg);
473 return ret;
474 }
475
476 list_add(&ccp_alg->entry, head);
477
478 ret = ccp_register_hmac_alg(head, def, ccp_alg);
479
480 return ret;
481 }
482
ccp_register_sha_algs(struct list_head * head)483 int ccp_register_sha_algs(struct list_head *head)
484 {
485 int i, ret;
486
487 for (i = 0; i < ARRAY_SIZE(sha_algs); i++) {
488 ret = ccp_register_sha_alg(head, &sha_algs[i]);
489 if (ret)
490 return ret;
491 }
492
493 return 0;
494 }
495