1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AMD Cryptographic Coprocessor (CCP) SHA crypto API support
4 *
5 * Copyright (C) 2013,2018 Advanced Micro Devices, Inc.
6 *
7 * Author: Tom Lendacky <thomas.lendacky@amd.com>
8 * Author: Gary R Hook <gary.hook@amd.com>
9 */
10
11#include <linux/module.h>
12#include <linux/sched.h>
13#include <linux/delay.h>
14#include <linux/scatterlist.h>
15#include <linux/crypto.h>
16#include <crypto/algapi.h>
17#include <crypto/hash.h>
18#include <crypto/hmac.h>
19#include <crypto/internal/hash.h>
20#include <crypto/sha1.h>
21#include <crypto/sha2.h>
22#include <crypto/scatterwalk.h>
23#include <linux/string.h>
24
25#include "ccp-crypto.h"
26
27static int ccp_sha_complete(struct crypto_async_request *async_req, int ret)
28{
29	struct ahash_request *req = ahash_request_cast(async_req);
30	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
31	struct ccp_sha_req_ctx *rctx = ahash_request_ctx_dma(req);
32	unsigned int digest_size = crypto_ahash_digestsize(tfm);
33
34	if (ret)
35		goto e_free;
36
37	if (rctx->hash_rem) {
38		/* Save remaining data to buffer */
39		unsigned int offset = rctx->nbytes - rctx->hash_rem;
40
41		scatterwalk_map_and_copy(rctx->buf, rctx->src,
42					 offset, rctx->hash_rem, 0);
43		rctx->buf_count = rctx->hash_rem;
44	} else {
45		rctx->buf_count = 0;
46	}
47
48	/* Update result area if supplied */
49	if (req->result && rctx->final)
50		memcpy(req->result, rctx->ctx, digest_size);
51
52e_free:
53	sg_free_table(&rctx->data_sg);
54
55	return ret;
56}
57
58static int ccp_do_sha_update(struct ahash_request *req, unsigned int nbytes,
59			     unsigned int final)
60{
61	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
62	struct ccp_ctx *ctx = crypto_ahash_ctx_dma(tfm);
63	struct ccp_sha_req_ctx *rctx = ahash_request_ctx_dma(req);
64	struct scatterlist *sg;
65	unsigned int block_size =
66		crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
67	unsigned int sg_count;
68	gfp_t gfp;
69	u64 len;
70	int ret;
71
72	len = (u64)rctx->buf_count + (u64)nbytes;
73
74	if (!final && (len <= block_size)) {
75		scatterwalk_map_and_copy(rctx->buf + rctx->buf_count, req->src,
76					 0, nbytes, 0);
77		rctx->buf_count += nbytes;
78
79		return 0;
80	}
81
82	rctx->src = req->src;
83	rctx->nbytes = nbytes;
84
85	rctx->final = final;
86	rctx->hash_rem = final ? 0 : len & (block_size - 1);
87	rctx->hash_cnt = len - rctx->hash_rem;
88	if (!final && !rctx->hash_rem) {
89		/* CCP can't do zero length final, so keep some data around */
90		rctx->hash_cnt -= block_size;
91		rctx->hash_rem = block_size;
92	}
93
94	/* Initialize the context scatterlist */
95	sg_init_one(&rctx->ctx_sg, rctx->ctx, sizeof(rctx->ctx));
96
97	sg = NULL;
98	if (rctx->buf_count && nbytes) {
99		/* Build the data scatterlist table - allocate enough entries
100		 * for both data pieces (buffer and input data)
101		 */
102		gfp = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
103			GFP_KERNEL : GFP_ATOMIC;
104		sg_count = sg_nents(req->src) + 1;
105		ret = sg_alloc_table(&rctx->data_sg, sg_count, gfp);
106		if (ret)
107			return ret;
108
109		sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count);
110		sg = ccp_crypto_sg_table_add(&rctx->data_sg, &rctx->buf_sg);
111		if (!sg) {
112			ret = -EINVAL;
113			goto e_free;
114		}
115		sg = ccp_crypto_sg_table_add(&rctx->data_sg, req->src);
116		if (!sg) {
117			ret = -EINVAL;
118			goto e_free;
119		}
120		sg_mark_end(sg);
121
122		sg = rctx->data_sg.sgl;
123	} else if (rctx->buf_count) {
124		sg_init_one(&rctx->buf_sg, rctx->buf, rctx->buf_count);
125
126		sg = &rctx->buf_sg;
127	} else if (nbytes) {
128		sg = req->src;
129	}
130
131	rctx->msg_bits += (rctx->hash_cnt << 3);	/* Total in bits */
132
133	memset(&rctx->cmd, 0, sizeof(rctx->cmd));
134	INIT_LIST_HEAD(&rctx->cmd.entry);
135	rctx->cmd.engine = CCP_ENGINE_SHA;
136	rctx->cmd.u.sha.type = rctx->type;
137	rctx->cmd.u.sha.ctx = &rctx->ctx_sg;
138
139	switch (rctx->type) {
140	case CCP_SHA_TYPE_1:
141		rctx->cmd.u.sha.ctx_len = SHA1_DIGEST_SIZE;
142		break;
143	case CCP_SHA_TYPE_224:
144		rctx->cmd.u.sha.ctx_len = SHA224_DIGEST_SIZE;
145		break;
146	case CCP_SHA_TYPE_256:
147		rctx->cmd.u.sha.ctx_len = SHA256_DIGEST_SIZE;
148		break;
149	case CCP_SHA_TYPE_384:
150		rctx->cmd.u.sha.ctx_len = SHA384_DIGEST_SIZE;
151		break;
152	case CCP_SHA_TYPE_512:
153		rctx->cmd.u.sha.ctx_len = SHA512_DIGEST_SIZE;
154		break;
155	default:
156		/* Should never get here */
157		break;
158	}
159
160	rctx->cmd.u.sha.src = sg;
161	rctx->cmd.u.sha.src_len = rctx->hash_cnt;
162	rctx->cmd.u.sha.opad = ctx->u.sha.key_len ?
163		&ctx->u.sha.opad_sg : NULL;
164	rctx->cmd.u.sha.opad_len = ctx->u.sha.key_len ?
165		ctx->u.sha.opad_count : 0;
166	rctx->cmd.u.sha.first = rctx->first;
167	rctx->cmd.u.sha.final = rctx->final;
168	rctx->cmd.u.sha.msg_bits = rctx->msg_bits;
169
170	rctx->first = 0;
171
172	ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
173
174	return ret;
175
176e_free:
177	sg_free_table(&rctx->data_sg);
178
179	return ret;
180}
181
182static int ccp_sha_init(struct ahash_request *req)
183{
184	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
185	struct ccp_ctx *ctx = crypto_ahash_ctx_dma(tfm);
186	struct ccp_sha_req_ctx *rctx = ahash_request_ctx_dma(req);
187	struct ccp_crypto_ahash_alg *alg =
188		ccp_crypto_ahash_alg(crypto_ahash_tfm(tfm));
189	unsigned int block_size =
190		crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
191
192	memset(rctx, 0, sizeof(*rctx));
193
194	rctx->type = alg->type;
195	rctx->first = 1;
196
197	if (ctx->u.sha.key_len) {
198		/* Buffer the HMAC key for first update */
199		memcpy(rctx->buf, ctx->u.sha.ipad, block_size);
200		rctx->buf_count = block_size;
201	}
202
203	return 0;
204}
205
206static int ccp_sha_update(struct ahash_request *req)
207{
208	return ccp_do_sha_update(req, req->nbytes, 0);
209}
210
211static int ccp_sha_final(struct ahash_request *req)
212{
213	return ccp_do_sha_update(req, 0, 1);
214}
215
216static int ccp_sha_finup(struct ahash_request *req)
217{
218	return ccp_do_sha_update(req, req->nbytes, 1);
219}
220
221static int ccp_sha_digest(struct ahash_request *req)
222{
223	int ret;
224
225	ret = ccp_sha_init(req);
226	if (ret)
227		return ret;
228
229	return ccp_sha_finup(req);
230}
231
232static int ccp_sha_export(struct ahash_request *req, void *out)
233{
234	struct ccp_sha_req_ctx *rctx = ahash_request_ctx_dma(req);
235	struct ccp_sha_exp_ctx state;
236
237	/* Don't let anything leak to 'out' */
238	memset(&state, 0, sizeof(state));
239
240	state.type = rctx->type;
241	state.msg_bits = rctx->msg_bits;
242	state.first = rctx->first;
243	memcpy(state.ctx, rctx->ctx, sizeof(state.ctx));
244	state.buf_count = rctx->buf_count;
245	memcpy(state.buf, rctx->buf, sizeof(state.buf));
246
247	/* 'out' may not be aligned so memcpy from local variable */
248	memcpy(out, &state, sizeof(state));
249
250	return 0;
251}
252
253static int ccp_sha_import(struct ahash_request *req, const void *in)
254{
255	struct ccp_sha_req_ctx *rctx = ahash_request_ctx_dma(req);
256	struct ccp_sha_exp_ctx state;
257
258	/* 'in' may not be aligned so memcpy to local variable */
259	memcpy(&state, in, sizeof(state));
260
261	memset(rctx, 0, sizeof(*rctx));
262	rctx->type = state.type;
263	rctx->msg_bits = state.msg_bits;
264	rctx->first = state.first;
265	memcpy(rctx->ctx, state.ctx, sizeof(rctx->ctx));
266	rctx->buf_count = state.buf_count;
267	memcpy(rctx->buf, state.buf, sizeof(rctx->buf));
268
269	return 0;
270}
271
272static int ccp_sha_setkey(struct crypto_ahash *tfm, const u8 *key,
273			  unsigned int key_len)
274{
275	struct ccp_ctx *ctx = crypto_ahash_ctx_dma(tfm);
276	struct crypto_shash *shash = ctx->u.sha.hmac_tfm;
277	unsigned int block_size = crypto_shash_blocksize(shash);
278	unsigned int digest_size = crypto_shash_digestsize(shash);
279	int i, ret;
280
281	/* Set to zero until complete */
282	ctx->u.sha.key_len = 0;
283
284	/* Clear key area to provide zero padding for keys smaller
285	 * than the block size
286	 */
287	memset(ctx->u.sha.key, 0, sizeof(ctx->u.sha.key));
288
289	if (key_len > block_size) {
290		/* Must hash the input key */
291		ret = crypto_shash_tfm_digest(shash, key, key_len,
292					      ctx->u.sha.key);
293		if (ret)
294			return -EINVAL;
295
296		key_len = digest_size;
297	} else {
298		memcpy(ctx->u.sha.key, key, key_len);
299	}
300
301	for (i = 0; i < block_size; i++) {
302		ctx->u.sha.ipad[i] = ctx->u.sha.key[i] ^ HMAC_IPAD_VALUE;
303		ctx->u.sha.opad[i] = ctx->u.sha.key[i] ^ HMAC_OPAD_VALUE;
304	}
305
306	sg_init_one(&ctx->u.sha.opad_sg, ctx->u.sha.opad, block_size);
307	ctx->u.sha.opad_count = block_size;
308
309	ctx->u.sha.key_len = key_len;
310
311	return 0;
312}
313
314static int ccp_sha_cra_init(struct crypto_tfm *tfm)
315{
316	struct crypto_ahash *ahash = __crypto_ahash_cast(tfm);
317	struct ccp_ctx *ctx = crypto_ahash_ctx_dma(ahash);
318
319	ctx->complete = ccp_sha_complete;
320	ctx->u.sha.key_len = 0;
321
322	crypto_ahash_set_reqsize_dma(ahash, sizeof(struct ccp_sha_req_ctx));
323
324	return 0;
325}
326
327static void ccp_sha_cra_exit(struct crypto_tfm *tfm)
328{
329}
330
331static int ccp_hmac_sha_cra_init(struct crypto_tfm *tfm)
332{
333	struct ccp_ctx *ctx = crypto_tfm_ctx_dma(tfm);
334	struct ccp_crypto_ahash_alg *alg = ccp_crypto_ahash_alg(tfm);
335	struct crypto_shash *hmac_tfm;
336
337	hmac_tfm = crypto_alloc_shash(alg->child_alg, 0, 0);
338	if (IS_ERR(hmac_tfm)) {
339		pr_warn("could not load driver %s need for HMAC support\n",
340			alg->child_alg);
341		return PTR_ERR(hmac_tfm);
342	}
343
344	ctx->u.sha.hmac_tfm = hmac_tfm;
345
346	return ccp_sha_cra_init(tfm);
347}
348
349static void ccp_hmac_sha_cra_exit(struct crypto_tfm *tfm)
350{
351	struct ccp_ctx *ctx = crypto_tfm_ctx_dma(tfm);
352
353	if (ctx->u.sha.hmac_tfm)
354		crypto_free_shash(ctx->u.sha.hmac_tfm);
355
356	ccp_sha_cra_exit(tfm);
357}
358
359struct ccp_sha_def {
360	unsigned int version;
361	const char *name;
362	const char *drv_name;
363	enum ccp_sha_type type;
364	u32 digest_size;
365	u32 block_size;
366};
367
368static struct ccp_sha_def sha_algs[] = {
369	{
370		.version	= CCP_VERSION(3, 0),
371		.name		= "sha1",
372		.drv_name	= "sha1-ccp",
373		.type		= CCP_SHA_TYPE_1,
374		.digest_size	= SHA1_DIGEST_SIZE,
375		.block_size	= SHA1_BLOCK_SIZE,
376	},
377	{
378		.version	= CCP_VERSION(3, 0),
379		.name		= "sha224",
380		.drv_name	= "sha224-ccp",
381		.type		= CCP_SHA_TYPE_224,
382		.digest_size	= SHA224_DIGEST_SIZE,
383		.block_size	= SHA224_BLOCK_SIZE,
384	},
385	{
386		.version	= CCP_VERSION(3, 0),
387		.name		= "sha256",
388		.drv_name	= "sha256-ccp",
389		.type		= CCP_SHA_TYPE_256,
390		.digest_size	= SHA256_DIGEST_SIZE,
391		.block_size	= SHA256_BLOCK_SIZE,
392	},
393	{
394		.version	= CCP_VERSION(5, 0),
395		.name		= "sha384",
396		.drv_name	= "sha384-ccp",
397		.type		= CCP_SHA_TYPE_384,
398		.digest_size	= SHA384_DIGEST_SIZE,
399		.block_size	= SHA384_BLOCK_SIZE,
400	},
401	{
402		.version	= CCP_VERSION(5, 0),
403		.name		= "sha512",
404		.drv_name	= "sha512-ccp",
405		.type		= CCP_SHA_TYPE_512,
406		.digest_size	= SHA512_DIGEST_SIZE,
407		.block_size	= SHA512_BLOCK_SIZE,
408	},
409};
410
411static int ccp_register_hmac_alg(struct list_head *head,
412				 const struct ccp_sha_def *def,
413				 const struct ccp_crypto_ahash_alg *base_alg)
414{
415	struct ccp_crypto_ahash_alg *ccp_alg;
416	struct ahash_alg *alg;
417	struct hash_alg_common *halg;
418	struct crypto_alg *base;
419	int ret;
420
421	ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
422	if (!ccp_alg)
423		return -ENOMEM;
424
425	/* Copy the base algorithm and only change what's necessary */
426	*ccp_alg = *base_alg;
427	INIT_LIST_HEAD(&ccp_alg->entry);
428
429	strscpy(ccp_alg->child_alg, def->name, CRYPTO_MAX_ALG_NAME);
430
431	alg = &ccp_alg->alg;
432	alg->setkey = ccp_sha_setkey;
433
434	halg = &alg->halg;
435
436	base = &halg->base;
437	snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)", def->name);
438	snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "hmac-%s",
439		 def->drv_name);
440	base->cra_init = ccp_hmac_sha_cra_init;
441	base->cra_exit = ccp_hmac_sha_cra_exit;
442
443	ret = crypto_register_ahash(alg);
444	if (ret) {
445		pr_err("%s ahash algorithm registration error (%d)\n",
446		       base->cra_name, ret);
447		kfree(ccp_alg);
448		return ret;
449	}
450
451	list_add(&ccp_alg->entry, head);
452
453	return ret;
454}
455
456static int ccp_register_sha_alg(struct list_head *head,
457				const struct ccp_sha_def *def)
458{
459	struct ccp_crypto_ahash_alg *ccp_alg;
460	struct ahash_alg *alg;
461	struct hash_alg_common *halg;
462	struct crypto_alg *base;
463	int ret;
464
465	ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
466	if (!ccp_alg)
467		return -ENOMEM;
468
469	INIT_LIST_HEAD(&ccp_alg->entry);
470
471	ccp_alg->type = def->type;
472
473	alg = &ccp_alg->alg;
474	alg->init = ccp_sha_init;
475	alg->update = ccp_sha_update;
476	alg->final = ccp_sha_final;
477	alg->finup = ccp_sha_finup;
478	alg->digest = ccp_sha_digest;
479	alg->export = ccp_sha_export;
480	alg->import = ccp_sha_import;
481
482	halg = &alg->halg;
483	halg->digestsize = def->digest_size;
484	halg->statesize = sizeof(struct ccp_sha_exp_ctx);
485
486	base = &halg->base;
487	snprintf(base->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
488	snprintf(base->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
489		 def->drv_name);
490	base->cra_flags = CRYPTO_ALG_ASYNC |
491			  CRYPTO_ALG_ALLOCATES_MEMORY |
492			  CRYPTO_ALG_KERN_DRIVER_ONLY |
493			  CRYPTO_ALG_NEED_FALLBACK;
494	base->cra_blocksize = def->block_size;
495	base->cra_ctxsize = sizeof(struct ccp_ctx) + crypto_dma_padding();
496	base->cra_priority = CCP_CRA_PRIORITY;
497	base->cra_init = ccp_sha_cra_init;
498	base->cra_exit = ccp_sha_cra_exit;
499	base->cra_module = THIS_MODULE;
500
501	ret = crypto_register_ahash(alg);
502	if (ret) {
503		pr_err("%s ahash algorithm registration error (%d)\n",
504		       base->cra_name, ret);
505		kfree(ccp_alg);
506		return ret;
507	}
508
509	list_add(&ccp_alg->entry, head);
510
511	ret = ccp_register_hmac_alg(head, def, ccp_alg);
512
513	return ret;
514}
515
516int ccp_register_sha_algs(struct list_head *head)
517{
518	int i, ret;
519	unsigned int ccpversion = ccp_version();
520
521	for (i = 0; i < ARRAY_SIZE(sha_algs); i++) {
522		if (sha_algs[i].version > ccpversion)
523			continue;
524		ret = ccp_register_sha_alg(head, &sha_algs[i]);
525		if (ret)
526			return ret;
527	}
528
529	return 0;
530}
531