1
// SPDX-License-Identifier: GPL-2.0
2
/*
3
 * sun8i-ce-cipher.c - hardware cryptographic offloader for
4
 * Allwinner H3/A64/H5/H2+/H6/R40 SoC
5
 *
6
 * Copyright (C) 2016-2019 Corentin LABBE <[email protected]>
7
 *
8
 * This file add support for AES cipher with 128,192,256 bits keysize in
9
 * CBC and ECB mode.
10
 *
11
 * You could find a link for the datasheet in Documentation/arch/arm/sunxi.rst
12
 */
13

14
#include <linux/bottom_half.h>
15
#include <linux/crypto.h>
16
#include <linux/dma-mapping.h>
17
#include <linux/io.h>
18
#include <linux/pm_runtime.h>
19
#include <crypto/scatterwalk.h>
20
#include <crypto/internal/des.h>
21
#include <crypto/internal/skcipher.h>
22
#include "sun8i-ce.h"
23

24
static int sun8i_ce_cipher_need_fallback(struct skcipher_request *areq)
25
{
26
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
27
	struct scatterlist *sg;
28
	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
29
	struct sun8i_ce_alg_template *algt;
30
	unsigned int todo, len;
31

32
	algt = container_of(alg, struct sun8i_ce_alg_template, alg.skcipher.base);
33

34
	if (sg_nents_for_len(areq->src, areq->cryptlen) > MAX_SG ||
35
	    sg_nents_for_len(areq->dst, areq->cryptlen) > MAX_SG) {
36
		if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
37
			algt->stat_fb_maxsg++;
38

39
		return true;
40
	}
41

42
	if (areq->cryptlen < crypto_skcipher_ivsize(tfm)) {
43
		if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
44
			algt->stat_fb_leniv++;
45

46
		return true;
47
	}
48

49
	if (areq->cryptlen == 0) {
50
		if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
51
			algt->stat_fb_len0++;
52

53
		return true;
54
	}
55

56
	if (areq->cryptlen % 16) {
57
		if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
58
			algt->stat_fb_mod16++;
59

60
		return true;
61
	}
62

63
	len = areq->cryptlen;
64
	sg = areq->src;
65
	while (sg) {
66
		if (!IS_ALIGNED(sg->offset, sizeof(u32))) {
67
			if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
68
				algt->stat_fb_srcali++;
69

70
			return true;
71
		}
72
		todo = min(len, sg->length);
73
		if (todo % 4) {
74
			if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
75
				algt->stat_fb_srclen++;
76

77
			return true;
78
		}
79
		len -= todo;
80
		sg = sg_next(sg);
81
	}
82

83
	len = areq->cryptlen;
84
	sg = areq->dst;
85
	while (sg) {
86
		if (!IS_ALIGNED(sg->offset, sizeof(u32))) {
87
			if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
88
				algt->stat_fb_dstali++;
89

90
			return true;
91
		}
92
		todo = min(len, sg->length);
93
		if (todo % 4) {
94
			if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
95
				algt->stat_fb_dstlen++;
96

97
			return true;
98
		}
99
		len -= todo;
100
		sg = sg_next(sg);
101
	}
102
	return false;
103
}
104

105
static int sun8i_ce_cipher_fallback(struct skcipher_request *areq)
106
{
107
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
108
	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
109
	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
110
	int err;
111

112
	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG)) {
113
		struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
114
		struct sun8i_ce_alg_template *algt;
115

116
		algt = container_of(alg, struct sun8i_ce_alg_template,
117
				    alg.skcipher.base);
118

119
		algt->stat_fb++;
120
	}
121

122
	skcipher_request_set_tfm(&rctx->fallback_req, op->fallback_tfm);
123
	skcipher_request_set_callback(&rctx->fallback_req, areq->base.flags,
124
				      areq->base.complete, areq->base.data);
125
	skcipher_request_set_crypt(&rctx->fallback_req, areq->src, areq->dst,
126
				   areq->cryptlen, areq->iv);
127
	if (rctx->op_dir & CE_DECRYPTION)
128
		err = crypto_skcipher_decrypt(&rctx->fallback_req);
129
	else
130
		err = crypto_skcipher_encrypt(&rctx->fallback_req);
131
	return err;
132
}
133

134
static int sun8i_ce_cipher_prepare(struct skcipher_request *areq,
135
				   struct ce_task *cet)
136
{
137
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
138
	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
139
	struct sun8i_ce_dev *ce = op->ce;
140
	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
141
	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
142
	struct sun8i_ce_alg_template *algt;
143
	struct scatterlist *sg;
144
	unsigned int todo, len, offset, ivsize;
145
	u32 common, sym;
146
	int i;
147
	int nr_sgs = 0;
148
	int nr_sgd = 0;
149
	int err = 0;
150
	int ns = sg_nents_for_len(areq->src, areq->cryptlen);
151
	int nd = sg_nents_for_len(areq->dst, areq->cryptlen);
152

153
	algt = container_of(alg, struct sun8i_ce_alg_template, alg.skcipher.base);
154

155
	dev_dbg(ce->dev, "%s %s %u %x IV(%p %u) key=%u\n", __func__,
156
		crypto_tfm_alg_name(areq->base.tfm),
157
		areq->cryptlen,
158
		rctx->op_dir, areq->iv, crypto_skcipher_ivsize(tfm),
159
		op->keylen);
160

161
	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
162
		algt->stat_req++;
163

164
	memset(cet, 0, sizeof(struct ce_task));
165

166
	cet->t_id = cpu_to_le32(rctx->flow);
167
	common = ce->variant->alg_cipher[algt->ce_algo_id];
168
	common |= rctx->op_dir | CE_COMM_INT;
169
	cet->t_common_ctl = cpu_to_le32(common);
170
	/* CTS and recent CE (H6) need length in bytes, in word otherwise */
171
	if (ce->variant->cipher_t_dlen_in_bytes)
172
		cet->t_dlen = cpu_to_le32(areq->cryptlen);
173
	else
174
		cet->t_dlen = cpu_to_le32(areq->cryptlen / 4);
175

176
	sym = ce->variant->op_mode[algt->ce_blockmode];
177
	len = op->keylen;
178
	switch (len) {
179
	case 128 / 8:
180
		sym |= CE_AES_128BITS;
181
		break;
182
	case 192 / 8:
183
		sym |= CE_AES_192BITS;
184
		break;
185
	case 256 / 8:
186
		sym |= CE_AES_256BITS;
187
		break;
188
	}
189

190
	cet->t_sym_ctl = cpu_to_le32(sym);
191
	cet->t_asym_ctl = 0;
192

193
	rctx->addr_key = dma_map_single(ce->dev, op->key, op->keylen, DMA_TO_DEVICE);
194
	if (dma_mapping_error(ce->dev, rctx->addr_key)) {
195
		dev_err(ce->dev, "Cannot DMA MAP KEY\n");
196
		err = -EFAULT;
197
		goto theend;
198
	}
199
	cet->t_key = desc_addr_val_le32(ce, rctx->addr_key);
200

201
	ivsize = crypto_skcipher_ivsize(tfm);
202
	if (areq->iv && ivsize > 0) {
203
		if (rctx->op_dir & CE_DECRYPTION) {
204
			offset = areq->cryptlen - ivsize;
205
			scatterwalk_map_and_copy(rctx->backup_iv, areq->src,
206
						 offset, ivsize, 0);
207
		}
208
		memcpy(rctx->bounce_iv, areq->iv, ivsize);
209
		rctx->addr_iv = dma_map_single(ce->dev, rctx->bounce_iv, ivsize,
210
					       DMA_TO_DEVICE);
211
		if (dma_mapping_error(ce->dev, rctx->addr_iv)) {
212
			dev_err(ce->dev, "Cannot DMA MAP IV\n");
213
			err = -ENOMEM;
214
			goto theend_iv;
215
		}
216
		cet->t_iv = desc_addr_val_le32(ce, rctx->addr_iv);
217
	}
218

219
	if (areq->src == areq->dst) {
220
		nr_sgs = dma_map_sg(ce->dev, areq->src, ns, DMA_BIDIRECTIONAL);
221
		if (nr_sgs <= 0 || nr_sgs > MAX_SG) {
222
			dev_err(ce->dev, "Invalid sg number %d\n", nr_sgs);
223
			err = -EINVAL;
224
			goto theend_iv;
225
		}
226
		nr_sgd = nr_sgs;
227
	} else {
228
		nr_sgs = dma_map_sg(ce->dev, areq->src, ns, DMA_TO_DEVICE);
229
		if (nr_sgs <= 0 || nr_sgs > MAX_SG) {
230
			dev_err(ce->dev, "Invalid sg number %d\n", nr_sgs);
231
			err = -EINVAL;
232
			goto theend_iv;
233
		}
234
		nr_sgd = dma_map_sg(ce->dev, areq->dst, nd, DMA_FROM_DEVICE);
235
		if (nr_sgd <= 0 || nr_sgd > MAX_SG) {
236
			dev_err(ce->dev, "Invalid sg number %d\n", nr_sgd);
237
			err = -EINVAL;
238
			goto theend_sgs;
239
		}
240
	}
241

242
	len = areq->cryptlen;
243
	for_each_sg(areq->src, sg, nr_sgs, i) {
244
		cet->t_src[i].addr = desc_addr_val_le32(ce, sg_dma_address(sg));
245
		todo = min(len, sg_dma_len(sg));
246
		cet->t_src[i].len = cpu_to_le32(todo / 4);
247
		dev_dbg(ce->dev, "%s total=%u SG(%d %u off=%d) todo=%u\n", __func__,
248
			areq->cryptlen, i, cet->t_src[i].len, sg->offset, todo);
249
		len -= todo;
250
	}
251
	if (len > 0) {
252
		dev_err(ce->dev, "remaining len %d\n", len);
253
		err = -EINVAL;
254
		goto theend_sgs;
255
	}
256

257
	len = areq->cryptlen;
258
	for_each_sg(areq->dst, sg, nr_sgd, i) {
259
		cet->t_dst[i].addr = desc_addr_val_le32(ce, sg_dma_address(sg));
260
		todo = min(len, sg_dma_len(sg));
261
		cet->t_dst[i].len = cpu_to_le32(todo / 4);
262
		dev_dbg(ce->dev, "%s total=%u SG(%d %u off=%d) todo=%u\n", __func__,
263
			areq->cryptlen, i, cet->t_dst[i].len, sg->offset, todo);
264
		len -= todo;
265
	}
266
	if (len > 0) {
267
		dev_err(ce->dev, "remaining len %d\n", len);
268
		err = -EINVAL;
269
		goto theend_sgs;
270
	}
271

272
	rctx->nr_sgs = ns;
273
	rctx->nr_sgd = nd;
274
	return 0;
275

276
theend_sgs:
277
	if (areq->src == areq->dst) {
278
		dma_unmap_sg(ce->dev, areq->src, ns, DMA_BIDIRECTIONAL);
279
	} else {
280
		if (nr_sgs > 0)
281
			dma_unmap_sg(ce->dev, areq->src, ns, DMA_TO_DEVICE);
282

283
		if (nr_sgd > 0)
284
			dma_unmap_sg(ce->dev, areq->dst, nd, DMA_FROM_DEVICE);
285
	}
286

287
theend_iv:
288
	if (areq->iv && ivsize > 0) {
289
		if (!dma_mapping_error(ce->dev, rctx->addr_iv))
290
			dma_unmap_single(ce->dev, rctx->addr_iv, ivsize,
291
					 DMA_TO_DEVICE);
292

293
		offset = areq->cryptlen - ivsize;
294
		if (rctx->op_dir & CE_DECRYPTION) {
295
			memcpy(areq->iv, rctx->backup_iv, ivsize);
296
			memzero_explicit(rctx->backup_iv, ivsize);
297
		} else {
298
			scatterwalk_map_and_copy(areq->iv, areq->dst, offset,
299
						 ivsize, 0);
300
		}
301
		memzero_explicit(rctx->bounce_iv, ivsize);
302
	}
303

304
	dma_unmap_single(ce->dev, rctx->addr_key, op->keylen, DMA_TO_DEVICE);
305

306
theend:
307
	return err;
308
}
309

310
static void sun8i_ce_cipher_unprepare(struct skcipher_request *areq,
311
				      struct ce_task *cet)
312
{
313
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
314
	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
315
	struct sun8i_ce_dev *ce = op->ce;
316
	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
317
	unsigned int ivsize, offset;
318
	int nr_sgs = rctx->nr_sgs;
319
	int nr_sgd = rctx->nr_sgd;
320

321
	ivsize = crypto_skcipher_ivsize(tfm);
322

323
	if (areq->src == areq->dst) {
324
		dma_unmap_sg(ce->dev, areq->src, nr_sgs, DMA_BIDIRECTIONAL);
325
	} else {
326
		if (nr_sgs > 0)
327
			dma_unmap_sg(ce->dev, areq->src, nr_sgs, DMA_TO_DEVICE);
328
		dma_unmap_sg(ce->dev, areq->dst, nr_sgd, DMA_FROM_DEVICE);
329
	}
330

331
	if (areq->iv && ivsize > 0) {
332
		if (cet->t_iv)
333
			dma_unmap_single(ce->dev, rctx->addr_iv, ivsize,
334
					 DMA_TO_DEVICE);
335
		offset = areq->cryptlen - ivsize;
336
		if (rctx->op_dir & CE_DECRYPTION) {
337
			memcpy(areq->iv, rctx->backup_iv, ivsize);
338
			memzero_explicit(rctx->backup_iv, ivsize);
339
		} else {
340
			scatterwalk_map_and_copy(areq->iv, areq->dst, offset,
341
						 ivsize, 0);
342
		}
343
		memzero_explicit(rctx->bounce_iv, ivsize);
344
	}
345

346
	dma_unmap_single(ce->dev, rctx->addr_key, op->keylen, DMA_TO_DEVICE);
347
}
348

349
int sun8i_ce_cipher_do_one(struct crypto_engine *engine, void *areq)
350
{
351
	struct skcipher_request *req = skcipher_request_cast(areq);
352
	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(req);
353
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
354
	struct sun8i_cipher_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
355
	struct sun8i_ce_dev *ce = ctx->ce;
356
	struct sun8i_ce_flow *chan;
357
	int err;
358

359
	chan = &ce->chanlist[rctx->flow];
360

361
	err = sun8i_ce_cipher_prepare(req, chan->tl);
362
	if (err)
363
		return err;
364

365
	err = sun8i_ce_run_task(ce, rctx->flow,
366
				crypto_tfm_alg_name(req->base.tfm));
367

368
	sun8i_ce_cipher_unprepare(req, chan->tl);
369

370
	local_bh_disable();
371
	crypto_finalize_skcipher_request(engine, req, err);
372
	local_bh_enable();
373

374
	return 0;
375
}
376

377
int sun8i_ce_skdecrypt(struct skcipher_request *areq)
378
{
379
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
380
	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
381
	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
382
	struct crypto_engine *engine;
383
	int e;
384

385
	rctx->op_dir = CE_DECRYPTION;
386
	if (sun8i_ce_cipher_need_fallback(areq))
387
		return sun8i_ce_cipher_fallback(areq);
388

389
	e = sun8i_ce_get_engine_number(op->ce);
390
	rctx->flow = e;
391
	engine = op->ce->chanlist[e].engine;
392

393
	return crypto_transfer_skcipher_request_to_engine(engine, areq);
394
}
395

396
int sun8i_ce_skencrypt(struct skcipher_request *areq)
397
{
398
	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
399
	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
400
	struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
401
	struct crypto_engine *engine;
402
	int e;
403

404
	rctx->op_dir = CE_ENCRYPTION;
405
	if (sun8i_ce_cipher_need_fallback(areq))
406
		return sun8i_ce_cipher_fallback(areq);
407

408
	e = sun8i_ce_get_engine_number(op->ce);
409
	rctx->flow = e;
410
	engine = op->ce->chanlist[e].engine;
411

412
	return crypto_transfer_skcipher_request_to_engine(engine, areq);
413
}
414

415
int sun8i_ce_cipher_init(struct crypto_tfm *tfm)
416
{
417
	struct sun8i_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
418
	struct sun8i_ce_alg_template *algt;
419
	const char *name = crypto_tfm_alg_name(tfm);
420
	struct crypto_skcipher *sktfm = __crypto_skcipher_cast(tfm);
421
	struct skcipher_alg *alg = crypto_skcipher_alg(sktfm);
422
	int err;
423

424
	memset(op, 0, sizeof(struct sun8i_cipher_tfm_ctx));
425

426
	algt = container_of(alg, struct sun8i_ce_alg_template, alg.skcipher.base);
427
	op->ce = algt->ce;
428

429
	op->fallback_tfm = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
430
	if (IS_ERR(op->fallback_tfm)) {
431
		dev_err(op->ce->dev, "ERROR: Cannot allocate fallback for %s %ld\n",
432
			name, PTR_ERR(op->fallback_tfm));
433
		return PTR_ERR(op->fallback_tfm);
434
	}
435

436
	crypto_skcipher_set_reqsize(sktfm, sizeof(struct sun8i_cipher_req_ctx) +
437
				    crypto_skcipher_reqsize(op->fallback_tfm));
438

439
	if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG))
440
		memcpy(algt->fbname,
441
		       crypto_skcipher_driver_name(op->fallback_tfm),
442
		       CRYPTO_MAX_ALG_NAME);
443

444
	err = pm_runtime_resume_and_get(op->ce->dev);
445
	if (err < 0)
446
		goto error_pm;
447

448
	return 0;
449
error_pm:
450
	crypto_free_skcipher(op->fallback_tfm);
451
	return err;
452
}
453

454
void sun8i_ce_cipher_exit(struct crypto_tfm *tfm)
455
{
456
	struct sun8i_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
457

458
	kfree_sensitive(op->key);
459
	crypto_free_skcipher(op->fallback_tfm);
460
	pm_runtime_put_sync_suspend(op->ce->dev);
461
}
462

463
int sun8i_ce_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
464
			unsigned int keylen)
465
{
466
	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
467
	struct sun8i_ce_dev *ce = op->ce;
468

469
	switch (keylen) {
470
	case 128 / 8:
471
		break;
472
	case 192 / 8:
473
		break;
474
	case 256 / 8:
475
		break;
476
	default:
477
		dev_dbg(ce->dev, "ERROR: Invalid keylen %u\n", keylen);
478
		return -EINVAL;
479
	}
480
	kfree_sensitive(op->key);
481
	op->keylen = keylen;
482
	op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
483
	if (!op->key)
484
		return -ENOMEM;
485

486
	crypto_skcipher_clear_flags(op->fallback_tfm, CRYPTO_TFM_REQ_MASK);
487
	crypto_skcipher_set_flags(op->fallback_tfm, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
488

489
	return crypto_skcipher_setkey(op->fallback_tfm, key, keylen);
490
}
491

492
int sun8i_ce_des3_setkey(struct crypto_skcipher *tfm, const u8 *key,
493
			 unsigned int keylen)
494
{
495
	struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
496
	int err;
497

498
	err = verify_skcipher_des3_key(tfm, key);
499
	if (err)
500
		return err;
501

502
	kfree_sensitive(op->key);
503
	op->keylen = keylen;
504
	op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
505
	if (!op->key)
506
		return -ENOMEM;
507

508
	crypto_skcipher_clear_flags(op->fallback_tfm, CRYPTO_TFM_REQ_MASK);
509
	crypto_skcipher_set_flags(op->fallback_tfm, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
510

511
	return crypto_skcipher_setkey(op->fallback_tfm, key, keylen);
512
}
513

514