summaryrefslogtreecommitdiff
path: root/crypto/morus640.c
blob: 5c48a7cb899e6f3e23076df0fc5a61e679fe02c3 (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
/*
 * The MORUS-640 Authenticated-Encryption Algorithm
 *
 * Copyright (c) 2016-2018 Ondrej Mosnacek <omosnacek@gmail.com>
 * Copyright (C) 2017-2018 Red Hat, Inc. All rights reserved.
 *
 * 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 <asm/unaligned.h>
#include <crypto/algapi.h>
#include <crypto/internal/aead.h>
#include <crypto/internal/skcipher.h>
#include <crypto/morus_common.h>
#include <crypto/scatterwalk.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/scatterlist.h>

#define MORUS640_WORD_SIZE 4
#define MORUS640_BLOCK_SIZE (MORUS_BLOCK_WORDS * MORUS640_WORD_SIZE)
#define MORUS640_BLOCK_ALIGN (__alignof__(__le32))
#define MORUS640_ALIGNED(p) IS_ALIGNED((uintptr_t)p, MORUS640_BLOCK_ALIGN)

struct morus640_block {
	u32 words[MORUS_BLOCK_WORDS];
};

union morus640_block_in {
	__le32 words[MORUS_BLOCK_WORDS];
	u8 bytes[MORUS640_BLOCK_SIZE];
};

struct morus640_state {
	struct morus640_block s[MORUS_STATE_BLOCKS];
};

struct morus640_ctx {
	struct morus640_block key;
};

struct morus640_ops {
	int (*skcipher_walk_init)(struct skcipher_walk *walk,
				  struct aead_request *req, bool atomic);

	void (*crypt_chunk)(struct morus640_state *state,
			    u8 *dst, const u8 *src, unsigned int size);
};

static const struct morus640_block crypto_morus640_const[2] = {
	{ .words = {
		U32_C(0x02010100),
		U32_C(0x0d080503),
		U32_C(0x59372215),
		U32_C(0x6279e990),
	} },
	{ .words = {
		U32_C(0x55183ddb),
		U32_C(0xf12fc26d),
		U32_C(0x42311120),
		U32_C(0xdd28b573),
	} },
};

static void crypto_morus640_round(struct morus640_block *b0,
				  struct morus640_block *b1,
				  struct morus640_block *b2,
				  struct morus640_block *b3,
				  struct morus640_block *b4,
				  const struct morus640_block *m,
				  unsigned int b, unsigned int w)
{
	unsigned int i;
	struct morus640_block tmp;

	for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
		b0->words[i] ^= b1->words[i] & b2->words[i];
		b0->words[i] ^= b3->words[i];
		b0->words[i] ^= m->words[i];
		b0->words[i] = rol32(b0->words[i], b);
	}

	tmp = *b3;
	for (i = 0; i < MORUS_BLOCK_WORDS; i++)
		b3->words[(i + w) % MORUS_BLOCK_WORDS] = tmp.words[i];
}

static void crypto_morus640_update(struct morus640_state *state,
				   const struct morus640_block *m)
{
	static const struct morus640_block z = {};

	struct morus640_block *s = state->s;

	crypto_morus640_round(&s[0], &s[1], &s[2], &s[3], &s[4], &z,  5, 1);
	crypto_morus640_round(&s[1], &s[2], &s[3], &s[4], &s[0], m,  31, 2);
	crypto_morus640_round(&s[2], &s[3], &s[4], &s[0], &s[1], m,   7, 3);
	crypto_morus640_round(&s[3], &s[4], &s[0], &s[1], &s[2], m,  22, 2);
	crypto_morus640_round(&s[4], &s[0], &s[1], &s[2], &s[3], m,  13, 1);
}

static void crypto_morus640_load_a(struct morus640_block *dst, const u8 *src)
{
	unsigned int i;
	for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
		dst->words[i] = le32_to_cpu(*(const __le32 *)src);
		src += MORUS640_WORD_SIZE;
	}
}

static void crypto_morus640_load_u(struct morus640_block *dst, const u8 *src)
{
	unsigned int i;
	for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
		dst->words[i] = get_unaligned_le32(src);
		src += MORUS640_WORD_SIZE;
	}
}

static void crypto_morus640_load(struct morus640_block *dst, const u8 *src)
{
	if (MORUS640_ALIGNED(src))
		crypto_morus640_load_a(dst, src);
	else
		crypto_morus640_load_u(dst, src);
}

static void crypto_morus640_store_a(u8 *dst, const struct morus640_block *src)
{
	unsigned int i;
	for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
		*(__le32 *)dst = cpu_to_le32(src->words[i]);
		dst += MORUS640_WORD_SIZE;
	}
}

static void crypto_morus640_store_u(u8 *dst, const struct morus640_block *src)
{
	unsigned int i;
	for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
		put_unaligned_le32(src->words[i], dst);
		dst += MORUS640_WORD_SIZE;
	}
}

static void crypto_morus640_store(u8 *dst, const struct morus640_block *src)
{
	if (MORUS640_ALIGNED(dst))
		crypto_morus640_store_a(dst, src);
	else
		crypto_morus640_store_u(dst, src);
}

static void crypto_morus640_ad(struct morus640_state *state, const u8 *src,
			       unsigned int size)
{
	struct morus640_block m;

	if (MORUS640_ALIGNED(src)) {
		while (size >= MORUS640_BLOCK_SIZE) {
			crypto_morus640_load_a(&m, src);
			crypto_morus640_update(state, &m);

			size -= MORUS640_BLOCK_SIZE;
			src += MORUS640_BLOCK_SIZE;
		}
	} else {
		while (size >= MORUS640_BLOCK_SIZE) {
			crypto_morus640_load_u(&m, src);
			crypto_morus640_update(state, &m);

			size -= MORUS640_BLOCK_SIZE;
			src += MORUS640_BLOCK_SIZE;
		}
	}
}

static void crypto_morus640_core(const struct morus640_state *state,
				 struct morus640_block *blk)
{
	unsigned int i;

	for (i = 0; i < MORUS_BLOCK_WORDS; i++)
		blk->words[(i + 3) % MORUS_BLOCK_WORDS] ^= state->s[1].words[i];

	for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
		blk->words[i] ^= state->s[0].words[i];
		blk->words[i] ^= state->s[2].words[i] & state->s[3].words[i];
	}
}

static void crypto_morus640_encrypt_chunk(struct morus640_state *state, u8 *dst,
					  const u8 *src, unsigned int size)
{
	struct morus640_block c, m;

	if (MORUS640_ALIGNED(src) && MORUS640_ALIGNED(dst)) {
		while (size >= MORUS640_BLOCK_SIZE) {
			crypto_morus640_load_a(&m, src);
			c = m;
			crypto_morus640_core(state, &c);
			crypto_morus640_store_a(dst, &c);
			crypto_morus640_update(state, &m);

			src += MORUS640_BLOCK_SIZE;
			dst += MORUS640_BLOCK_SIZE;
			size -= MORUS640_BLOCK_SIZE;
		}
	} else {
		while (size >= MORUS640_BLOCK_SIZE) {
			crypto_morus640_load_u(&m, src);
			c = m;
			crypto_morus640_core(state, &c);
			crypto_morus640_store_u(dst, &c);
			crypto_morus640_update(state, &m);

			src += MORUS640_BLOCK_SIZE;
			dst += MORUS640_BLOCK_SIZE;
			size -= MORUS640_BLOCK_SIZE;
		}
	}

	if (size > 0) {
		union morus640_block_in tail;

		memcpy(tail.bytes, src, size);
		memset(tail.bytes + size, 0, MORUS640_BLOCK_SIZE - size);

		crypto_morus640_load_a(&m, tail.bytes);
		c = m;
		crypto_morus640_core(state, &c);
		crypto_morus640_store_a(tail.bytes, &c);
		crypto_morus640_update(state, &m);

		memcpy(dst, tail.bytes, size);
	}
}

static void crypto_morus640_decrypt_chunk(struct morus640_state *state, u8 *dst,
					  const u8 *src, unsigned int size)
{
	struct morus640_block m;

	if (MORUS640_ALIGNED(src) && MORUS640_ALIGNED(dst)) {
		while (size >= MORUS640_BLOCK_SIZE) {
			crypto_morus640_load_a(&m, src);
			crypto_morus640_core(state, &m);
			crypto_morus640_store_a(dst, &m);
			crypto_morus640_update(state, &m);

			src += MORUS640_BLOCK_SIZE;
			dst += MORUS640_BLOCK_SIZE;
			size -= MORUS640_BLOCK_SIZE;
		}
	} else {
		while (size >= MORUS640_BLOCK_SIZE) {
			crypto_morus640_load_u(&m, src);
			crypto_morus640_core(state, &m);
			crypto_morus640_store_u(dst, &m);
			crypto_morus640_update(state, &m);

			src += MORUS640_BLOCK_SIZE;
			dst += MORUS640_BLOCK_SIZE;
			size -= MORUS640_BLOCK_SIZE;
		}
	}

	if (size > 0) {
		union morus640_block_in tail;

		memcpy(tail.bytes, src, size);

		crypto_morus640_load_a(&m, src);
		crypto_morus640_core(state, &m);
		crypto_morus640_store_a(tail.bytes, &m);
		memset(tail.bytes + size, 0, MORUS640_BLOCK_SIZE - size);
		crypto_morus640_load_a(&m, tail.bytes);
		crypto_morus640_update(state, &m);

		memcpy(dst, tail.bytes, size);
	}
}

static void crypto_morus640_init(struct morus640_state *state,
				 const struct morus640_block *key,
				 const u8 *iv)
{
	static const struct morus640_block z = {};

	unsigned int i;

	crypto_morus640_load(&state->s[0], iv);
	state->s[1] = *key;
	for (i = 0; i < MORUS_BLOCK_WORDS; i++)
		state->s[2].words[i] = U32_C(0xFFFFFFFF);
	state->s[3] = crypto_morus640_const[0];
	state->s[4] = crypto_morus640_const[1];

	for (i = 0; i < 16; i++)
		crypto_morus640_update(state, &z);

	for (i = 0; i < MORUS_BLOCK_WORDS; i++)
		state->s[1].words[i] ^= key->words[i];
}

static void crypto_morus640_process_ad(struct morus640_state *state,
				       struct scatterlist *sg_src,
				       unsigned int assoclen)
{
	struct scatter_walk walk;
	struct morus640_block m;
	union morus640_block_in buf;
	unsigned int pos = 0;

	scatterwalk_start(&walk, sg_src);
	while (assoclen != 0) {
		unsigned int size = scatterwalk_clamp(&walk, assoclen);
		unsigned int left = size;
		void *mapped = scatterwalk_map(&walk);
		const u8 *src = (const u8 *)mapped;

		if (pos + size >= MORUS640_BLOCK_SIZE) {
			if (pos > 0) {
				unsigned int fill = MORUS640_BLOCK_SIZE - pos;
				memcpy(buf.bytes + pos, src, fill);

				crypto_morus640_load_a(&m, buf.bytes);
				crypto_morus640_update(state, &m);

				pos = 0;
				left -= fill;
				src += fill;
			}

			crypto_morus640_ad(state, src, left);
			src += left & ~(MORUS640_BLOCK_SIZE - 1);
			left &= MORUS640_BLOCK_SIZE - 1;
		}

		memcpy(buf.bytes + pos, src, left);

		pos += left;
		assoclen -= size;
		scatterwalk_unmap(mapped);
		scatterwalk_advance(&walk, size);
		scatterwalk_done(&walk, 0, assoclen);
	}

	if (pos > 0) {
		memset(buf.bytes + pos, 0, MORUS640_BLOCK_SIZE - pos);

		crypto_morus640_load_a(&m, buf.bytes);
		crypto_morus640_update(state, &m);
	}
}

static void crypto_morus640_process_crypt(struct morus640_state *state,
					  struct aead_request *req,
					  const struct morus640_ops *ops)
{
	struct skcipher_walk walk;
	u8 *dst;
	const u8 *src;

	ops->skcipher_walk_init(&walk, req, false);

	while (walk.nbytes) {
		src = walk.src.virt.addr;
		dst = walk.dst.virt.addr;

		ops->crypt_chunk(state, dst, src, walk.nbytes);

		skcipher_walk_done(&walk, 0);
	}
}

static void crypto_morus640_final(struct morus640_state *state,
				  struct morus640_block *tag_xor,
				  u64 assoclen, u64 cryptlen)
{
	u64 assocbits = assoclen * 8;
	u64 cryptbits = cryptlen * 8;

	u32 assocbits_lo = (u32)assocbits;
	u32 assocbits_hi = (u32)(assocbits >> 32);
	u32 cryptbits_lo = (u32)cryptbits;
	u32 cryptbits_hi = (u32)(cryptbits >> 32);

	struct morus640_block tmp;
	unsigned int i;

	tmp.words[0] = cpu_to_le32(assocbits_lo);
	tmp.words[1] = cpu_to_le32(assocbits_hi);
	tmp.words[2] = cpu_to_le32(cryptbits_lo);
	tmp.words[3] = cpu_to_le32(cryptbits_hi);

	for (i = 0; i < MORUS_BLOCK_WORDS; i++)
		state->s[4].words[i] ^= state->s[0].words[i];

	for (i = 0; i < 10; i++)
		crypto_morus640_update(state, &tmp);

	crypto_morus640_core(state, tag_xor);
}

static int crypto_morus640_setkey(struct crypto_aead *aead, const u8 *key,
				  unsigned int keylen)
{
	struct morus640_ctx *ctx = crypto_aead_ctx(aead);

	if (keylen != MORUS640_BLOCK_SIZE) {
		crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN);
		return -EINVAL;
	}

	crypto_morus640_load(&ctx->key, key);
	return 0;
}

static int crypto_morus640_setauthsize(struct crypto_aead *tfm,
				       unsigned int authsize)
{
	return (authsize <= MORUS_MAX_AUTH_SIZE) ? 0 : -EINVAL;
}

static void crypto_morus640_crypt(struct aead_request *req,
				  struct morus640_block *tag_xor,
				  unsigned int cryptlen,
				  const struct morus640_ops *ops)
{
	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
	struct morus640_ctx *ctx = crypto_aead_ctx(tfm);
	struct morus640_state state;

	crypto_morus640_init(&state, &ctx->key, req->iv);
	crypto_morus640_process_ad(&state, req->src, req->assoclen);
	crypto_morus640_process_crypt(&state, req, ops);
	crypto_morus640_final(&state, tag_xor, req->assoclen, cryptlen);
}

static int crypto_morus640_encrypt(struct aead_request *req)
{
	static const struct morus640_ops ops = {
		.skcipher_walk_init = skcipher_walk_aead_encrypt,
		.crypt_chunk = crypto_morus640_encrypt_chunk,
	};

	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
	struct morus640_block tag = {};
	union morus640_block_in tag_out;
	unsigned int authsize = crypto_aead_authsize(tfm);
	unsigned int cryptlen = req->cryptlen;

	crypto_morus640_crypt(req, &tag, cryptlen, &ops);
	crypto_morus640_store(tag_out.bytes, &tag);

	scatterwalk_map_and_copy(tag_out.bytes, req->dst,
				 req->assoclen + cryptlen, authsize, 1);
	return 0;
}

static int crypto_morus640_decrypt(struct aead_request *req)
{
	static const struct morus640_ops ops = {
		.skcipher_walk_init = skcipher_walk_aead_decrypt,
		.crypt_chunk = crypto_morus640_decrypt_chunk,
	};
	static const u8 zeros[MORUS640_BLOCK_SIZE] = {};

	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
	union morus640_block_in tag_in;
	struct morus640_block tag;
	unsigned int authsize = crypto_aead_authsize(tfm);
	unsigned int cryptlen = req->cryptlen - authsize;

	scatterwalk_map_and_copy(tag_in.bytes, req->src,
				 req->assoclen + cryptlen, authsize, 0);

	crypto_morus640_load(&tag, tag_in.bytes);
	crypto_morus640_crypt(req, &tag, cryptlen, &ops);
	crypto_morus640_store(tag_in.bytes, &tag);

	return crypto_memneq(tag_in.bytes, zeros, authsize) ? -EBADMSG : 0;
}

static int crypto_morus640_init_tfm(struct crypto_aead *tfm)
{
	return 0;
}

static void crypto_morus640_exit_tfm(struct crypto_aead *tfm)
{
}

static struct aead_alg crypto_morus640_alg = {
	.setkey = crypto_morus640_setkey,
	.setauthsize = crypto_morus640_setauthsize,
	.encrypt = crypto_morus640_encrypt,
	.decrypt = crypto_morus640_decrypt,
	.init = crypto_morus640_init_tfm,
	.exit = crypto_morus640_exit_tfm,

	.ivsize = MORUS_NONCE_SIZE,
	.maxauthsize = MORUS_MAX_AUTH_SIZE,
	.chunksize = MORUS640_BLOCK_SIZE,

	.base = {
		.cra_blocksize = 1,
		.cra_ctxsize = sizeof(struct morus640_ctx),
		.cra_alignmask = 0,

		.cra_priority = 100,

		.cra_name = "morus640",
		.cra_driver_name = "morus640-generic",

		.cra_module = THIS_MODULE,
	}
};

static int __init crypto_morus640_module_init(void)
{
	return crypto_register_aead(&crypto_morus640_alg);
}

static void __exit crypto_morus640_module_exit(void)
{
	crypto_unregister_aead(&crypto_morus640_alg);
}

module_init(crypto_morus640_module_init);
module_exit(crypto_morus640_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>");
MODULE_DESCRIPTION("MORUS-640 AEAD algorithm");
MODULE_ALIAS_CRYPTO("morus640");
MODULE_ALIAS_CRYPTO("morus640-generic");