aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/crypto/padlock-sha.c
blob: 710f3cb816bceac3c304936ea5caf503ace5210b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
/*
 * Cryptographic API.
 *
 * Support for VIA PadLock hardware crypto engine.
 *
 * Copyright (c) 2006  Michal Ludvig <michal@logix.cz>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 */

#include <crypto/internal/hash.h>
#include <crypto/padlock.h>
#include <crypto/sha.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/scatterlist.h>
#include <asm/i387.h>

struct padlock_sha_desc {
	struct shash_desc fallback;
};

struct padlock_sha_ctx {
	struct crypto_shash *fallback;
};

static int padlock_sha_init(struct shash_desc *desc)
{
	struct padlock_sha_desc *dctx = shash_desc_ctx(desc);
	struct padlock_sha_ctx *ctx = crypto_shash_ctx(desc->tfm);

	dctx->fallback.tfm = ctx->fallback;
	dctx->fallback.flags = desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
	return crypto_shash_init(&dctx->fallback);
}

static int padlock_sha_update(struct shash_desc *desc,
			      const u8 *data, unsigned int length)
{
	struct padlock_sha_desc *dctx = shash_desc_ctx(desc);

	dctx->fallback.flags = desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
	return crypto_shash_update(&dctx->fallback, data, length);
}

static int padlock_sha_export(struct shash_desc *desc, void *out)
{
	struct padlock_sha_desc *dctx = shash_desc_ctx(desc);

	return crypto_shash_export(&dctx->fallback, out);
}

static int padlock_sha_import(struct shash_desc *desc, const void *in)
{
	struct padlock_sha_desc *dctx = shash_desc_ctx(desc);
	struct padlock_sha_ctx *ctx = crypto_shash_ctx(desc->tfm);

	dctx->fallback.tfm = ctx->fallback;
	dctx->fallback.flags = desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
	return crypto_shash_import(&dctx->fallback, in);
}

static inline void padlock_output_block(uint32_t *src,
		 	uint32_t *dst, size_t count)
{
	while (count--)
		*dst++ = swab32(*src++);
}

static int padlock_sha1_finup(struct shash_desc *desc, const u8 *in,
			      unsigned int count, u8 *out)
{
	/* We can't store directly to *out as it may be unaligned. */
	/* BTW Don't reduce the buffer size below 128 Bytes!
	 *     PadLock microcode needs it that big. */
	char buf[128 + PADLOCK_ALIGNMENT - STACK_ALIGN] __attribute__
		((aligned(STACK_ALIGN)));
	char *result = PTR_ALIGN(&buf[0], PADLOCK_ALIGNMENT);
	struct padlock_sha_desc *dctx = shash_desc_ctx(desc);
	struct sha1_state state;
	unsigned int space;
	unsigned int leftover;
	int ts_state;
	int err;

	dctx->fallback.flags = desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
	err = crypto_shash_export(&dctx->fallback, &state);
	if (err)
		goto out;

	if (state.count + count > ULONG_MAX)
		return crypto_shash_finup(&dctx->fallback, in, count, out);

	leftover = ((state.count - 1) & (SHA1_BLOCK_SIZE - 1)) + 1;
	space =  SHA1_BLOCK_SIZE - leftover;
	if (space) {
		if (count > space) {
			err = crypto_shash_update(&dctx->fallback, in, space) ?:
			      crypto_shash_export(&dctx->fallback, &state);
			if (err)
				goto out;
			count -= space;
			in += space;
		} else {
			memcpy(state.buffer + leftover, in, count);
			in = state.buffer;
			count += leftover;
			state.count &= ~(SHA1_BLOCK_SIZE - 1);
		}
	}

	memcpy(result, &state.state, SHA1_DIGEST_SIZE);

	/* prevent taking the spurious DNA fault with padlock. */
	ts_state = irq_ts_save();
	asm volatile (".byte 0xf3,0x0f,0xa6,0xc8" /* rep xsha1 */
		      : \
		      : "c"((unsigned long)state.count + count), \
			"a"((unsigned long)state.count), \
			"S"(in), "D"(result));
	irq_ts_restore(ts_state);

	padlock_output_block((uint32_t *)result, (uint32_t *)out, 5);

out:
	return err;
}

static int padlock_sha1_final(struct shash_desc *desc, u8 *out)
{
	u8 buf[4];

	return padlock_sha1_finup(desc, buf, 0, out);
}

static int padlock_sha256_finup(struct shash_desc *desc, const u8 *in,
				unsigned int count, u8 *out)
{
	/* We can't store directly to *out as it may be unaligned. */
	/* BTW Don't reduce the buffer size below 128 Bytes!
	 *     PadLock microcode needs it that big. */
	char buf[128 + PADLOCK_ALIGNMENT - STACK_ALIGN] __attribute__
		((aligned(STACK_ALIGN)));
	char *result = PTR_ALIGN(&buf[0], PADLOCK_ALIGNMENT);
	struct padlock_sha_desc *dctx = shash_desc_ctx(desc);
	struct sha256_state state;
	unsigned int space;
	unsigned int leftover;
	int ts_state;
	int err;

	dctx->fallback.flags = desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
	err = crypto_shash_export(&dctx->fallback, &state);
	if (err)
		goto out;

	if (state.count + count > ULONG_MAX)
		return crypto_shash_finup(&dctx->fallback, in, count, out);

	leftover = ((state.count - 1) & (SHA256_BLOCK_SIZE - 1)) + 1;
	space =  SHA256_BLOCK_SIZE - leftover;
	if (space) {
		if (count > space) {
			err = crypto_shash_update(&dctx->fallback, in, space) ?:
			      crypto_shash_export(&dctx->fallback, &state);
			if (err)
				goto out;
			count -= space;
			in += space;
		} else {
			memcpy(state.buf + leftover, in, count);
			in = state.buf;
			count += leftover;
			state.count &= ~(SHA1_BLOCK_SIZE - 1);
		}
	}

	memcpy(result, &state.state, SHA256_DIGEST_SIZE);

	/* prevent taking the spurious DNA fault with padlock. */
	ts_state = irq_ts_save();
	asm volatile (".byte 0xf3,0x0f,0xa6,0xd0" /* rep xsha256 */
		      : \
		      : "c"((unsigned long)state.count + count), \
			"a"((unsigned long)state.count), \
			"S"(in), "D"(result));
	irq_ts_restore(ts_state);

	padlock_output_block((uint32_t *)result, (uint32_t *)out, 8);

out:
	return err;
}

static int padlock_sha256_final(struct shash_desc *desc, u8 *out)
{
	u8 buf[4];

	return padlock_sha256_finup(desc, buf, 0, out);
}

static int padlock_cra_init(struct crypto_tfm *tfm)
{
	struct crypto_shash *hash = __crypto_shash_cast(tfm);
	const char *fallback_driver_name = tfm->__crt_alg->cra_name;
	struct padlock_sha_ctx *ctx = crypto_tfm_ctx(tfm);
	struct crypto_shash *fallback_tfm;
	int err = -ENOMEM;

	/* Allocate a fallback and abort if it failed. */
	fallback_tfm = crypto_alloc_shash(fallback_driver_name, 0,
					  CRYPTO_ALG_NEED_FALLBACK);
	if (IS_ERR(fallback_tfm)) {
		printk(KERN_WARNING PFX "Fallback driver '%s' could not be loaded!\n",
		       fallback_driver_name);
		err = PTR_ERR(fallback_tfm);
		goto out;
	}

	ctx->fallback = fallback_tfm;
	hash->descsize += crypto_shash_descsize(fallback_tfm);
	return 0;

out:
	return err;
}

static void padlock_cra_exit(struct crypto_tfm *tfm)
{
	struct padlock_sha_ctx *ctx = crypto_tfm_ctx(tfm);

	crypto_free_shash(ctx->fallback);
}

static struct shash_alg sha1_alg = {
	.digestsize	=	SHA1_DIGEST_SIZE,
	.init   	= 	padlock_sha_init,
	.update 	=	padlock_sha_update,
	.finup  	=	padlock_sha1_finup,
	.final  	=	padlock_sha1_final,
	.export		=	padlock_sha_export,
	.import		=	padlock_sha_import,
	.descsize	=	sizeof(struct padlock_sha_desc),
	.statesize	=	sizeof(struct sha1_state),
	.base		=	{
		.cra_name		=	"sha1",
		.cra_driver_name	=	"sha1-padlock",
		.cra_priority		=	PADLOCK_CRA_PRIORITY,
		.cra_flags		=	CRYPTO_ALG_TYPE_SHASH |
						CRYPTO_ALG_NEED_FALLBACK,
		.cra_blocksize		=	SHA1_BLOCK_SIZE,
		.cra_ctxsize		=	sizeof(struct padlock_sha_ctx),
		.cra_module		=	THIS_MODULE,
		.cra_init		=	padlock_cra_init,
		.cra_exit		=	padlock_cra_exit,
	}
};

static struct shash_alg sha256_alg = {
	.digestsize	=	SHA256_DIGEST_SIZE,
	.init   	= 	padlock_sha_init,
	.update 	=	padlock_sha_update,
	.finup  	=	padlock_sha256_finup,
	.final  	=	padlock_sha256_final,
	.export		=	padlock_sha_export,
	.import		=	padlock_sha_import,
	.descsize	=	sizeof(struct padlock_sha_desc),
	.statesize	=	sizeof(struct sha256_state),
	.base		=	{
		.cra_name		=	"sha256",
		.cra_driver_name	=	"sha256-padlock",
		.cra_priority		=	PADLOCK_CRA_PRIORITY,
		.cra_flags		=	CRYPTO_ALG_TYPE_SHASH |
						CRYPTO_ALG_NEED_FALLBACK,
		.cra_blocksize		=	SHA256_BLOCK_SIZE,
		.cra_ctxsize		=	sizeof(struct padlock_sha_ctx),
		.cra_module		=	THIS_MODULE,
		.cra_init		=	padlock_cra_init,
		.cra_exit		=	padlock_cra_exit,
	}
};

/* Add two shash_alg instance for hardware-implemented *
* multiple-parts hash supported by VIA Nano Processor.*/
static int padlock_sha1_init_nano(struct shash_desc *desc)
{
	struct sha1_state *sctx = shash_desc_ctx(desc);

	*sctx = (struct sha1_state){
		.state = { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 },
	};

	return 0;
}

static int padlock_sha1_update_nano(struct shash_desc *desc,
			const u8 *data,	unsigned int len)
{
	struct sha1_state *sctx = shash_desc_ctx(desc);
	unsigned int partial, done;
	const u8 *src;
	/*The PHE require the out buffer must 128 bytes and 16-bytes aligned*/
	u8 buf[128 + PADLOCK_ALIGNMENT - STACK_ALIGN] __attribute__
		((aligned(STACK_ALIGN)));
	u8 *dst = PTR_ALIGN(&buf[0], PADLOCK_ALIGNMENT);
	int ts_state;

	partial = sctx->count & 0x3f;
	sctx->count += len;
	done = 0;
	src = data;
	memcpy(dst, (u8 *)(sctx->state), SHA1_DIGEST_SIZE);

	if ((partial + len) >= SHA1_BLOCK_SIZE) {

		/* Append the bytes in state's buffer to a block to handle */
		if (partial) {
			done = -partial;
			memcpy(sctx->buffer + partial, data,
				done + SHA1_BLOCK_SIZE);
			src = sctx->buffer;
			ts_state = irq_ts_save();
			asm volatile (".byte 0xf3,0x0f,0xa6,0xc8"
			: "+S"(src), "+D"(dst) \
			: "a"((long)-1), "c"((unsigned long)1));
			irq_ts_restore(ts_state);
			done += SHA1_BLOCK_SIZE;
			src = data + done;
		}

		/* Process the left bytes from the input data */
		if (len - done >= SHA1_BLOCK_SIZE) {
			ts_state = irq_ts_save();
			asm volatile (".byte 0xf3,0x0f,0xa6,0xc8"
			: "+S"(src), "+D"(dst)
			: "a"((long)-1),
			"c"((unsigned long)((len - done) / SHA1_BLOCK_SIZE)));
			irq_ts_restore(ts_state);
			done += ((len - done) - (len - done) % SHA1_BLOCK_SIZE);
			src = data + done;
		}
		partial = 0;
	}
	memcpy((u8 *)(sctx->state), dst, SHA1_DIGEST_SIZE);
	memcpy(sctx->buffer + partial, src, len - done);

	return 0;
}

static int padlock_sha1_final_nano(struct shash_desc *desc, u8 *out)
{
	struct sha1_state *state = (struct sha1_state *)shash_desc_ctx(desc);
	unsigned int partial, padlen;
	__be64 bits;
	static const u8 padding[64] = { 0x80, };

	bits = cpu_to_be64(state->count << 3);

	/* Pad out to 56 mod 64 */
	partial = state->count & 0x3f;
	padlen = (partial < 56) ? (56 - partial) : ((64+56) - partial);
	padlock_sha1_update_nano(desc, padding, padlen);

	/* Append length field bytes */
	padlock_sha1_update_nano(desc, (const u8 *)&bits, sizeof(bits));

	/* Swap to output */
	padlock_output_block((uint32_t *)(state->state), (uint32_t *)out, 5);

	return 0;
}

static int padlock_sha256_init_nano(struct shash_desc *desc)
{
	struct sha256_state *sctx = shash_desc_ctx(desc);

	*sctx = (struct sha256_state){
		.state = { SHA256_H0, SHA256_H1, SHA256_H2, SHA256_H3, \
				SHA256_H4, SHA256_H5, SHA256_H6, SHA256_H7},
	};

	return 0;
}

static int padlock_sha256_update_nano(struct shash_desc *desc, const u8 *data,
			  unsigned int len)
{
	struct sha256_state *sctx = shash_desc_ctx(desc);
	unsigned int partial, done;
	const u8 *src;
	/*The PHE require the out buffer must 128 bytes and 16-bytes aligned*/
	u8 buf[128 + PADLOCK_ALIGNMENT - STACK_ALIGN] __attribute__
		((aligned(STACK_ALIGN)));
	u8 *dst = PTR_ALIGN(&buf[0], PADLOCK_ALIGNMENT);
	int ts_state;

	partial = sctx->count & 0x3f;
	sctx->count += len;
	done = 0;
	src = data;
	memcpy(dst, (u8 *)(sctx->state), SHA256_DIGEST_SIZE);

	if ((partial + len) >= SHA256_BLOCK_SIZE) {

		/* Append the bytes in state's buffer to a block to handle */
		if (partial) {
			done = -partial;
			memcpy(sctx->buf + partial, data,
				done + SHA256_BLOCK_SIZE);
			src = sctx->buf;
			ts_state = irq_ts_save();
			asm volatile (".byte 0xf3,0x0f,0xa6,0xd0"
			: "+S"(src), "+D"(dst)
			: "a"((long)-1), "c"((unsigned long)1));
			irq_ts_restore(ts_state);
			done += SHA256_BLOCK_SIZE;
			src = data + done;
		}

		/* Process the left bytes from input data*/
		if (len - done >= SHA256_BLOCK_SIZE) {
			ts_state = irq_ts_save();
			asm volatile (".byte 0xf3,0x0f,0xa6,0xd0"
			: "+S"(src), "+D"(dst)
			: "a"((long)-1),
			"c"((unsigned long)((len - done) / 64)));
			irq_ts_restore(ts_state);
			done += ((len - done) - (len - done) % 64);
			src = data + done;
		}
		partial = 0;
	}
	memcpy((u8 *)(sctx->state), dst, SHA256_DIGEST_SIZE);
	memcpy(sctx->buf + partial, src, len - done);

	return 0;
}

static int padlock_sha256_final_nano(struct shash_desc *desc, u8 *out)
{
	struct sha256_state *state =
		(struct sha256_state *)shash_desc_ctx(desc);
	unsigned int partial, padlen;
	__be64 bits;
	static const u8 padding[64] = { 0x80, };

	bits = cpu_to_be64(state->count << 3);

	/* Pad out to 56 mod 64 */
	partial = state->count & 0x3f;
	padlen = (partial < 56) ? (56 - partial) : ((64+56) - partial);
	padlock_sha256_update_nano(desc, padding, padlen);

	/* Append length field bytes */
	padlock_sha256_update_nano(desc, (const u8 *)&bits, sizeof(bits));

	/* Swap to output */
	padlock_output_block((uint32_t *)(state->state), (uint32_t *)out, 8);

	return 0;
}

static int padlock_sha_export_nano(struct shash_desc *desc,
				void *out)
{
	int statesize = crypto_shash_statesize(desc->tfm);
	void *sctx = shash_desc_ctx(desc);

	memcpy(out, sctx, statesize);
	return 0;
}

static int padlock_sha_import_nano(struct shash_desc *desc,
				const void *in)
{
	int statesize = crypto_shash_statesize(desc->tfm);
	void *sctx = shash_desc_ctx(desc);

	memcpy(sctx, in, statesize);
	return 0;
}

static struct shash_alg sha1_alg_nano = {
	.digestsize	=	SHA1_DIGEST_SIZE,
	.init		=	padlock_sha1_init_nano,
	.update		=	padlock_sha1_update_nano,
	.final		=	padlock_sha1_final_nano,
	.export		=	padlock_sha_export_nano,
	.import		=	padlock_sha_import_nano,
	.descsize	=	sizeof(struct sha1_state),
	.statesize	=	sizeof(struct sha1_state),
	.base		=	{
		.cra_name		=	"sha1",
		.cra_driver_name	=	"sha1-padlock-nano",
		.cra_priority		=	PADLOCK_CRA_PRIORITY,
		.cra_flags		=	CRYPTO_ALG_TYPE_SHASH,
		.cra_blocksize		=	SHA1_BLOCK_SIZE,
		.cra_module		=	THIS_MODULE,
	}
};

static struct shash_alg sha256_alg_nano = {
	.digestsize	=	SHA256_DIGEST_SIZE,
	.init		=	padlock_sha256_init_nano,
	.update		=	padlock_sha256_update_nano,
	.final		=	padlock_sha256_final_nano,
	.export		=	padlock_sha_export_nano,
	.import		=	padlock_sha_import_nano,
	.descsize	=	sizeof(struct sha256_state),
	.statesize	=	sizeof(struct sha256_state),
	.base		=	{
		.cra_name		=	"sha256",
		.cra_driver_name	=	"sha256-padlock-nano",
		.cra_priority		=	PADLOCK_CRA_PRIORITY,
		.cra_flags		=	CRYPTO_ALG_TYPE_SHASH,
		.cra_blocksize		=	SHA256_BLOCK_SIZE,
		.cra_module		=	THIS_MODULE,
	}
};

static int __init padlock_init(void)
{
	int rc = -ENODEV;
	struct cpuinfo_x86 *c = &cpu_data(0);
	struct shash_alg *sha1;
	struct shash_alg *sha256;

	if (!cpu_has_phe) {
		printk(KERN_NOTICE PFX "VIA PadLock Hash Engine not detected.\n");
		return -ENODEV;
	}

	if (!cpu_has_phe_enabled) {
		printk(KERN_NOTICE PFX "VIA PadLock detected, but not enabled. Hmm, strange...\n");
		return -ENODEV;
	}

	/* Register the newly added algorithm module if on *
	* VIA Nano processor, or else just do as before */
	if (c->x86_model < 0x0f) {
		sha1 = &sha1_alg;
		sha256 = &sha256_alg;
	} else {
		sha1 = &sha1_alg_nano;
		sha256 = &sha256_alg_nano;
	}

	rc = crypto_register_shash(sha1);
	if (rc)
		goto out;

	rc = crypto_register_shash(sha256);
	if (rc)
		goto out_unreg1;

	printk(KERN_NOTICE PFX "Using VIA PadLock ACE for SHA1/SHA256 algorithms.\n");

	return 0;

out_unreg1:
	crypto_unregister_shash(sha1);

out:
	printk(KERN_ERR PFX "VIA PadLock SHA1/SHA256 initialization failed.\n");
	return rc;
}

static void __exit padlock_fini(void)
{
	struct cpuinfo_x86 *c = &cpu_data(0);

	if (c->x86_model >= 0x0f) {
		crypto_unregister_shash(&sha1_alg_nano);
		crypto_unregister_shash(&sha256_alg_nano);
	} else {
		crypto_unregister_shash(&sha1_alg);
		crypto_unregister_shash(&sha256_alg);
	}
}

module_init(padlock_init);
module_exit(padlock_fini);

MODULE_DESCRIPTION("VIA PadLock SHA1/SHA256 algorithms support.");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Michal Ludvig");

MODULE_ALIAS_CRYPTO("sha1-all");
MODULE_ALIAS_CRYPTO("sha256-all");
MODULE_ALIAS_CRYPTO("sha1-padlock");
MODULE_ALIAS_CRYPTO("sha256-padlock");