1/*
2 * AMD Cryptographic Coprocessor (CCP) SHA crypto API support
3 *
4 * Copyright (C) 2013,2018 Advanced Micro Devices, Inc.
5 *
6 * Author: Tom Lendacky <thomas.lendacky@amd.com>
7 * Author: Gary R Hook <gary.hook@amd.com>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13
14#include <linux/module.h>
15#include <linux/sched.h>
16#include <linux/delay.h>
17#include <linux/scatterlist.h>
18#include <linux/crypto.h>
19#include <crypto/algapi.h>
20#include <crypto/hash.h>
21#include <crypto/hmac.h>
22#include <crypto/internal/hash.h>
23#include <crypto/sha.h>
24#include <crypto/scatterwalk.h>
25
26#include "ccp-crypto.h"
27
28static int ccp_sha_complete(struct crypto_async_request *async_req, int ret)
29{
30 struct ahash_request *req = ahash_request_cast(async_req);
31 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
32 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
33 unsigned int digest_size = crypto_ahash_digestsize(tfm);
34
35 if (ret)
36 goto e_free;
37
38 if (rctx->hash_rem) {
39 /* Save remaining data to buffer */
40 unsigned int offset = rctx->nbytes - rctx->hash_rem;
41
42 scatterwalk_map_and_copy(rctx->buf, rctx->src,
43 offset, rctx->hash_rem, 0);
44 rctx->buf_count = rctx->hash_rem;
45 } else {
46 rctx->buf_count = 0;
47 }
48
49 /* Update result area if supplied */
50 if (req->result && rctx->final)
51 memcpy(req->result, rctx->ctx, digest_size);
52
53e_free:
54 sg_free_table(&rctx->data_sg);
55
56 return ret;
57}
58
59static int ccp_do_sha_update(struct ahash_request *req, unsigned int nbytes,
60 unsigned int final)
61{
62 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
63 struct ccp_ctx *ctx = crypto_ahash_ctx(tfm);
64 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
65 struct scatterlist *sg;
66 unsigned int block_size =
67 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
68 unsigned int sg_count;
69 gfp_t gfp;
70 u64 len;
71 int ret;
72
73 len = (u64)rctx->buf_count + (u64)nbytes;
74
75 if (!final && (len <= block_size)) {
76 scatterwalk_map_and_copy(rctx->buf + rctx->buf_count, req->src,
77 0, nbytes, 0);
78 rctx->buf_count += nbytes;
79
80 return 0;
81 }
82
83 rctx->src = req->src;
84 rctx->nbytes = nbytes;
85
86 rctx->final = final;
87 rctx->hash_rem = final ? 0 : len & (block_size - 1);
88 rctx->hash_cnt = len - rctx->hash_rem;
89 if (!final && !rctx->hash_rem) {
90 /* CCP can't do zero length final, so keep some data around */
91 rctx->hash_cnt -= block_size;
92 rctx->hash_rem = block_size;
93 }
94
95 /* Initialize the context scatterlist */
96 sg_init_one(&rctx->ctx_sg, rctx->ctx, sizeof(rctx->ctx));
97
98 sg = NULL;
99 if (rctx->buf_count && nbytes) {
100 /* Build the data scatterlist table - allocate enough entries
101 * for both data pieces (buffer and input data)
102 */
103 gfp = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
104 GFP_KERNEL : GFP_ATOMIC;
105 sg_count = sg_nents(req->src) + 1;
106 ret = sg_alloc_table(&rctx->data_sg, sg_count, gfp);
107 if (ret)
108 return ret;
109
110 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count);
111 sg = ccp_crypto_sg_table_add(&rctx->data_sg, &rctx->buf_sg);
112 if (!sg) {
113 ret = -EINVAL;
114 goto e_free;
115 }
116 sg = ccp_crypto_sg_table_add(&rctx->data_sg, req->src);
117 if (!sg) {
118 ret = -EINVAL;
119 goto e_free;
120 }
121 sg_mark_end(sg);
122
123 sg = rctx->data_sg.sgl;
124 } else if (rctx->buf_count) {
125 sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count);
126
127 sg = &rctx->buf_sg;
128 } else if (nbytes) {
129 sg = req->src;
130 }
131
132 rctx->msg_bits += (rctx->hash_cnt << 3); /* Total in bits */
133
134 memset(&rctx->cmd, 0, sizeof(rctx->cmd));
135 INIT_LIST_HEAD(&rctx->cmd.entry);
136 rctx->cmd.engine = CCP_ENGINE_SHA;
137 rctx->cmd.u.sha.type = rctx->type;
138 rctx->cmd.u.sha.ctx = &rctx->ctx_sg;
139
140 switch (rctx->type) {
141 case CCP_SHA_TYPE_1:
142 rctx->cmd.u.sha.ctx_len = SHA1_DIGEST_SIZE;
143 break;
144 case CCP_SHA_TYPE_224:
145 rctx->cmd.u.sha.ctx_len = SHA224_DIGEST_SIZE;
146 break;
147 case CCP_SHA_TYPE_256:
148 rctx->cmd.u.sha.ctx_len = SHA256_DIGEST_SIZE;
149 break;
150 case CCP_SHA_TYPE_384:
151 rctx->cmd.u.sha.ctx_len = SHA384_DIGEST_SIZE;
152 break;
153 case CCP_SHA_TYPE_512:
154 rctx->cmd.u.sha.ctx_len = SHA512_DIGEST_SIZE;
155 break;
156 default:
157 /* Should never get here */
158 break;
159 }
160
161 rctx->cmd.u.sha.src = sg;
162 rctx->cmd.u.sha.src_len = rctx->hash_cnt;
163 rctx->cmd.u.sha.opad = ctx->u.sha.key_len ?
164 &ctx->u.sha.opad_sg : NULL;
165 rctx->cmd.u.sha.opad_len = ctx->u.sha.key_len ?
166 ctx->u.sha.opad_count : 0;
167 rctx->cmd.u.sha.first = rctx->first;
168 rctx->cmd.u.sha.final = rctx->final;
169 rctx->cmd.u.sha.msg_bits = rctx->msg_bits;
170
171 rctx->first = 0;
172
173 ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
174
175 return ret;
176
177e_free:
178 sg_free_table(&rctx->data_sg);
179
180 return ret;
181}
182
183static int ccp_sha_init(struct ahash_request *req)
184{
185 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
186 struct ccp_ctx *ctx = crypto_ahash_ctx(tfm);
187 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
188 struct ccp_crypto_ahash_alg *alg =
189 ccp_crypto_ahash_alg(crypto_ahash_tfm(tfm));
190 unsigned int block_size =
191 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
192
193 memset(rctx, 0, sizeof(*rctx));
194
195 rctx->type = alg->type;
196 rctx->first = 1;
197
198 if (ctx->u.sha.key_len) {
199 /* Buffer the HMAC key for first update */
200 memcpy(rctx->buf, ctx->u.sha.ipad, block_size);
201 rctx->buf_count = block_size;
202 }
203
204 return 0;
205}
206
207static int ccp_sha_update(struct ahash_request *req)
208{
209 return ccp_do_sha_update(req, req->nbytes, 0);
210}
211
212static int ccp_sha_final(struct ahash_request *req)
213{
214 return ccp_do_sha_update(req, 0, 1);
215}
216
217static int ccp_sha_finup(struct ahash_request *req)
218{
219 return ccp_do_sha_update(req, req->nbytes, 1);
220}
221
222static int ccp_sha_digest(struct ahash_request *req)
223{
224 int ret;
225
226 ret = ccp_sha_init(req);
227 if (ret)
228 return ret;
229
230 return ccp_sha_finup(req);
231}
232
233static int ccp_sha_export(struct ahash_request *req, void *out)
234{
235 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
236 struct ccp_sha_exp_ctx state;
237
238 /* Don't let anything leak to 'out' */
239 memset(&state, 0, sizeof(state));
240
241 state.type = rctx->type;
242 state.msg_bits = rctx->msg_bits;
243 state.first = rctx->first;
244 memcpy(state.ctx, rctx->ctx, sizeof(state.ctx));
245 state.buf_count = rctx->buf_count;
246 memcpy(state.buf, rctx->buf, sizeof(state.buf));
247
248 /* 'out' may not be aligned so memcpy from local variable */
249 memcpy(out, &state, sizeof(state));
250
251 return 0;
252}
253
254static int ccp_sha_import(struct ahash_request *req, const void *in)
255{
256 struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
257 struct ccp_sha_exp_ctx state;
258
259 /* 'in' may not be aligned so memcpy to local variable */
260 memcpy(&state, in, sizeof(state));
261
262 memset(rctx, 0, sizeof(*rctx));
263 rctx->type = state.type;
264 rctx->msg_bits = state.msg_bits;
265 rctx->first = state.first;
266 memcpy(rctx->ctx, state.ctx, sizeof(rctx->ctx));
267 rctx->buf_count = state.buf_count;
268 memcpy(rctx->buf, state.buf, sizeof(rctx->buf));
269
270 return 0;
271}
272
273static int ccp_sha_setkey(struct crypto_ahash *tfm, const u8 *key,
274 unsigned int key_len)
275{
276 struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm));
277 struct crypto_shash *shash = ctx->u.sha.hmac_tfm;
278
279 SHASH_DESC_ON_STACK(sdesc, shash);
280
281 unsigned int block_size = crypto_shash_blocksize(shash);
282 unsigned int digest_size = crypto_shash_digestsize(shash);
283 int i, ret;
284
285 /* Set to zero until complete */
286 ctx->u.sha.key_len = 0;
287
288 /* Clear key area to provide zero padding for keys smaller
289 * than the block size
290 */
291 memset(ctx->u.sha.key, 0, sizeof(ctx->u.sha.key));
292
293 if (key_len > block_size) {
294 /* Must hash the input key */
295 sdesc->tfm = shash;
296 sdesc->flags = crypto_ahash_get_flags(tfm) &
297 CRYPTO_TFM_REQ_MAY_SLEEP;
298
299 ret = crypto_shash_digest(sdesc, key, key_len,
300 ctx->u.sha.key);
301 if (ret) {
302 crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
303 return -EINVAL;
304 }
305
306 key_len = digest_size;
307 } else {
308 memcpy(ctx->u.sha.key, key, key_len);
309 }
310
311 for (i = 0; i < block_size; i++) {
312 ctx->u.sha.ipad[i] = ctx->u.sha.key[i] ^ HMAC_IPAD_VALUE;
313 ctx->u.sha.opad[i] = ctx->u.sha.key[i] ^ HMAC_OPAD_VALUE;
314 }
315
316 sg_init_one(&ctx->u.sha.opad_sg, ctx->u.sha.opad, block_size);
317 ctx->u.sha.opad_count = block_size;
318
319 ctx->u.sha.key_len = key_len;
320
321 return 0;
322}
323
324static int ccp_sha_cra_init(struct crypto_tfm *tfm)
325{
326 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
327 struct crypto_ahash *ahash = __crypto_ahash_cast(tfm);
328
329 ctx->complete = ccp_sha_complete;
330 ctx->u.sha.key_len = 0;
331
332 crypto_ahash_set_reqsize(ahash, sizeof(struct ccp_sha_req_ctx));
333
334 return 0;
335}
336
337static void ccp_sha_cra_exit(struct crypto_tfm *tfm)
338{
339}
340
341static int ccp_hmac_sha_cra_init(struct crypto_tfm *tfm)
342{
343 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
344 struct ccp_crypto_ahash_alg *alg = ccp_crypto_ahash_alg(tfm);
345 struct crypto_shash *hmac_tfm;
346
347 hmac_tfm = crypto_alloc_shash(alg->child_alg, 0, 0);
348 if (IS_ERR(hmac_tfm)) {
349 pr_warn("could not load driver %s need for HMAC support\n",
350 alg->child_alg);
351 return PTR_ERR(hmac_tfm);
352 }
353
354 ctx->u.sha.hmac_tfm = hmac_tfm;
355
356 return ccp_sha_cra_init(tfm);
357}
358
359static void ccp_hmac_sha_cra_exit(struct crypto_tfm *tfm)
360{
361 struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
362
363 if (ctx->u.sha.hmac_tfm)
364 crypto_free_shash(ctx->u.sha.hmac_tfm);
365
366 ccp_sha_cra_exit(tfm);
367}
368
369struct ccp_sha_def {
370 unsigned int version;
371 const char *name;
372 const char *drv_name;
373 enum ccp_sha_type type;
374 u32 digest_size;
375 u32 block_size;
376};
377
378static struct ccp_sha_def sha_algs[] = {
379 {
380 .version = CCP_VERSION(3, 0),
381 .name = "sha1",
382 .drv_name = "sha1-ccp",
383 .type = CCP_SHA_TYPE_1,
384 .digest_size = SHA1_DIGEST_SIZE,
385 .block_size = SHA1_BLOCK_SIZE,
386 },
387 {
388 .version = CCP_VERSION(3, 0),
389 .name = "sha224",
390 .drv_name = "sha224-ccp",
391 .type = CCP_SHA_TYPE_224,
392 .digest_size = SHA224_DIGEST_SIZE,
393 .block_size = SHA224_BLOCK_SIZE,
394 },
395 {
396 .version = CCP_VERSION(3, 0),
397 .name = "sha256",
398 .drv_name = "sha256-ccp",
399 .type = CCP_SHA_TYPE_256,
400 .digest_size = SHA256_DIGEST_SIZE,
401 .block_size = SHA256_BLOCK_SIZE,
402 },
403 {
404 .version = CCP_VERSION(5, 0),
405 .name = "sha384",
406 .drv_name = "sha384-ccp",
407 .type = CCP_SHA_TYPE_384,
408 .digest_size = SHA384_DIGEST_SIZE,
409 .block_size = SHA384_BLOCK_SIZE,
410 },
411 {
412 .version = CCP_VERSION(5, 0),
413 .name = "sha512",
414 .drv_name = "sha512-ccp",
415 .type = CCP_SHA_TYPE_512,
416 .digest_size = SHA512_DIGEST_SIZE,
417 .block_size = SHA512_BLOCK_SIZE,
418 },
419};
420
421static int ccp_register_hmac_alg(struct list_head *head,
422 const struct ccp_sha_def *def,
423 const struct ccp_crypto_ahash_alg *base_alg)
424{
425 struct ccp_crypto_ahash_alg *ccp_alg;
426 struct ahash_alg *alg;
427 struct hash_alg_common *halg;
428 struct crypto_alg *base;
429 int ret;
430
431 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
432 if (!ccp_alg)
433 return -ENOMEM;
434
435 /* Copy the base algorithm and only change what's necessary */
436 *ccp_alg = *base_alg;
437 INIT_LIST_HEAD(&ccp_alg->entry);
438
439 strncpy(ccp_alg->child_alg, def->name, CRYPTO_MAX_ALG_NAME);
440
441 alg = &ccp_alg->alg;
442 alg->setkey = ccp_sha_setkey;
443
444 halg = &alg->halg;
445
446 base = &halg->base;
447 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)", def->name);
448 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "hmac-%s",
449 def->drv_name);
450 base->cra_init = ccp_hmac_sha_cra_init;
451 base->cra_exit = ccp_hmac_sha_cra_exit;
452
453 ret = crypto_register_ahash(alg);
454 if (ret) {
455 pr_err("%s ahash algorithm registration error (%d)\n",
456 base->cra_name, ret);
457 kfree(ccp_alg);
458 return ret;
459 }
460
461 list_add(&ccp_alg->entry, head);
462
463 return ret;
464}
465
466static int ccp_register_sha_alg(struct list_head *head,
467 const struct ccp_sha_def *def)
468{
469 struct ccp_crypto_ahash_alg *ccp_alg;
470 struct ahash_alg *alg;
471 struct hash_alg_common *halg;
472 struct crypto_alg *base;
473 int ret;
474
475 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
476 if (!ccp_alg)
477 return -ENOMEM;
478
479 INIT_LIST_HEAD(&ccp_alg->entry);
480
481 ccp_alg->type = def->type;
482
483 alg = &ccp_alg->alg;
484 alg->init = ccp_sha_init;
485 alg->update = ccp_sha_update;
486 alg->final = ccp_sha_final;
487 alg->finup = ccp_sha_finup;
488 alg->digest = ccp_sha_digest;
489 alg->export = ccp_sha_export;
490 alg->import = ccp_sha_import;
491
492 halg = &alg->halg;
493 halg->digestsize = def->digest_size;
494 halg->statesize = sizeof(struct ccp_sha_exp_ctx);
495
496 base = &halg->base;
497 snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
498 snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
499 def->drv_name);
500 base->cra_flags = CRYPTO_ALG_ASYNC |
501 CRYPTO_ALG_KERN_DRIVER_ONLY |
502 CRYPTO_ALG_NEED_FALLBACK;
503 base->cra_blocksize = def->block_size;
504 base->cra_ctxsize = sizeof(struct ccp_ctx);
505 base->cra_priority = CCP_CRA_PRIORITY;
506 base->cra_init = ccp_sha_cra_init;
507 base->cra_exit = ccp_sha_cra_exit;
508 base->cra_module = THIS_MODULE;
509
510 ret = crypto_register_ahash(alg);
511 if (ret) {
512 pr_err("%s ahash algorithm registration error (%d)\n",
513 base->cra_name, ret);
514 kfree(ccp_alg);
515 return ret;
516 }
517
518 list_add(&ccp_alg->entry, head);
519
520 ret = ccp_register_hmac_alg(head, def, ccp_alg);
521
522 return ret;
523}
524
525int ccp_register_sha_algs(struct list_head *head)
526{
527 int i, ret;
528 unsigned int ccpversion = ccp_version();
529
530 for (i = 0; i < ARRAY_SIZE(sha_algs); i++) {
531 if (sha_algs[i].version > ccpversion)
532 continue;
533 ret = ccp_register_sha_alg(head, &sha_algs[i]);
534 if (ret)
535 return ret;
536 }
537
538 return 0;
539}
540