GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libcrypto/gost/gostr341001.c Lines: 0 166 0.0 %
Date: 2017-11-13 Branches: 0 162 0.0 %

Line Branch Exec Source
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/* $OpenBSD: gostr341001.c,v 1.7 2017/01/29 17:49:23 beck Exp $ */
2
/*
3
 * Copyright (c) 2014 Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
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 * Copyright (c) 2005-2006 Cryptocom LTD
5
 *
6
 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 *
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 *
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in
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 *    the documentation and/or other materials provided with the
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 *    distribution.
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 *
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 * 3. All advertising materials mentioning features or use of this
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 *    software must display the following acknowledgment:
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 *    "This product includes software developed by the OpenSSL Project
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 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
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 *
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 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
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 *    endorse or promote products derived from this software without
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 *    prior written permission. For written permission, please contact
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 *    openssl-core@openssl.org.
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 *
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 * 5. Products derived from this software may not be called "OpenSSL"
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 *    nor may "OpenSSL" appear in their names without prior written
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 *    permission of the OpenSSL Project.
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 *
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 * 6. Redistributions of any form whatsoever must retain the following
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 *    acknowledgment:
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 *    "This product includes software developed by the OpenSSL Project
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 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
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 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
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 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
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 * OF THE POSSIBILITY OF SUCH DAMAGE.
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 * ====================================================================
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 */
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52
#include <string.h>
53
54
#include <openssl/opensslconf.h>
55
56
#ifndef OPENSSL_NO_GOST
57
#include <openssl/bn.h>
58
#include <openssl/err.h>
59
#include <openssl/gost.h>
60
61
#include "bn_lcl.h"
62
#include "gost_locl.h"
63
64
/* Convert little-endian byte array into bignum */
65
BIGNUM *
66
GOST_le2bn(const unsigned char *buf, size_t len, BIGNUM *bn)
67
{
68
	unsigned char temp[64];
69
	int i;
70
71
	if (len > 64)
72
		return NULL;
73
74
	for (i = 0; i < len; i++) {
75
		temp[len - 1 - i] = buf[i];
76
	}
77
78
	return BN_bin2bn(temp, len, bn);
79
}
80
81
int
82
GOST_bn2le(BIGNUM *bn, unsigned char *buf, int len)
83
{
84
	unsigned char temp[64];
85
	int i, bytes;
86
87
	bytes = BN_num_bytes(bn);
88
	if (len > 64 || bytes > len)
89
		return 0;
90
91
	BN_bn2bin(bn, temp);
92
93
	for (i = 0; i < bytes; i++) {
94
		buf[bytes - 1 - i] = temp[i];
95
	}
96
97
	memset(buf + bytes, 0, len - bytes);
98
99
	return 1;
100
}
101
102
int
103
gost2001_compute_public(GOST_KEY *ec)
104
{
105
	const EC_GROUP *group = GOST_KEY_get0_group(ec);
106
	EC_POINT *pub_key = NULL;
107
	const BIGNUM *priv_key = NULL;
108
	BN_CTX *ctx = NULL;
109
	int ok = 0;
110
111
	if (group == NULL) {
112
		GOSTerror(GOST_R_KEY_IS_NOT_INITIALIZED);
113
		return 0;
114
	}
115
	ctx = BN_CTX_new();
116
	if (ctx == NULL) {
117
		GOSTerror(ERR_R_MALLOC_FAILURE);
118
		return 0;
119
	}
120
	BN_CTX_start(ctx);
121
	if ((priv_key = GOST_KEY_get0_private_key(ec)) == NULL)
122
		goto err;
123
124
	pub_key = EC_POINT_new(group);
125
	if (pub_key == NULL)
126
		goto err;
127
	if (EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, ctx) == 0)
128
		goto err;
129
	if (GOST_KEY_set_public_key(ec, pub_key) == 0)
130
		goto err;
131
	ok = 1;
132
133
	if (ok == 0) {
134
err:
135
		GOSTerror(ERR_R_EC_LIB);
136
	}
137
	EC_POINT_free(pub_key);
138
	if (ctx != NULL) {
139
		BN_CTX_end(ctx);
140
		BN_CTX_free(ctx);
141
	}
142
	return ok;
143
}
144
145
ECDSA_SIG *
146
gost2001_do_sign(BIGNUM *md, GOST_KEY *eckey)
147
{
148
	ECDSA_SIG *newsig = NULL;
149
	BIGNUM *order = NULL;
150
	const EC_GROUP *group;
151
	const BIGNUM *priv_key;
152
	BIGNUM *r = NULL, *s = NULL, *X = NULL, *tmp = NULL, *tmp2 = NULL, *k =
153
	    NULL, *e = NULL;
154
	EC_POINT *C = NULL;
155
	BN_CTX *ctx = BN_CTX_new();
156
	int ok = 0;
157
158
	if (ctx == NULL) {
159
		GOSTerror(ERR_R_MALLOC_FAILURE);
160
		return NULL;
161
	}
162
	BN_CTX_start(ctx);
163
	newsig = ECDSA_SIG_new();
164
	if (newsig == NULL) {
165
		GOSTerror(ERR_R_MALLOC_FAILURE);
166
		goto err;
167
	}
168
	s = newsig->s;
169
	r = newsig->r;
170
	group = GOST_KEY_get0_group(eckey);
171
	if ((order = BN_CTX_get(ctx)) == NULL)
172
		goto err;
173
	if (EC_GROUP_get_order(group, order, ctx) == 0)
174
		goto err;
175
	priv_key = GOST_KEY_get0_private_key(eckey);
176
	if ((e = BN_CTX_get(ctx)) == NULL)
177
		goto err;
178
	if (BN_mod_ct(e, md, order, ctx) == 0)
179
		goto err;
180
	if (BN_is_zero(e))
181
		BN_one(e);
182
	if ((k = BN_CTX_get(ctx)) == NULL)
183
		goto err;
184
	if ((X = BN_CTX_get(ctx)) == NULL)
185
		goto err;
186
	if ((C = EC_POINT_new(group)) == NULL)
187
		goto err;
188
	do {
189
		do {
190
			if (!BN_rand_range(k, order)) {
191
				GOSTerror(GOST_R_RANDOM_NUMBER_GENERATOR_FAILED);
192
				goto err;
193
			}
194
			/*
195
			 * We do not want timing information to leak the length
196
			 * of k, so we compute G*k using an equivalent scalar
197
			 * of fixed bit-length.
198
			 */
199
			if (BN_add(k, k, order) == 0)
200
				goto err;
201
			if (BN_num_bits(k) <= BN_num_bits(order))
202
				if (BN_add(k, k, order) == 0)
203
					goto err;
204
205
			if (EC_POINT_mul(group, C, k, NULL, NULL, ctx) == 0) {
206
				GOSTerror(ERR_R_EC_LIB);
207
				goto err;
208
			}
209
			if (EC_POINT_get_affine_coordinates_GFp(group, C, X,
210
			    NULL, ctx) == 0) {
211
				GOSTerror(ERR_R_EC_LIB);
212
				goto err;
213
			}
214
			if (BN_nnmod(r, X, order, ctx) == 0)
215
				goto err;
216
		} while (BN_is_zero(r));
217
		/* s = (r*priv_key+k*e) mod order */
218
		if (tmp == NULL) {
219
			if ((tmp = BN_CTX_get(ctx)) == NULL)
220
				goto err;
221
		}
222
		if (BN_mod_mul(tmp, priv_key, r, order, ctx) == 0)
223
			goto err;
224
		if (tmp2 == NULL) {
225
			if ((tmp2 = BN_CTX_get(ctx)) == NULL)
226
				goto err;
227
		}
228
		if (BN_mod_mul(tmp2, k, e, order, ctx) == 0)
229
			goto err;
230
		if (BN_mod_add(s, tmp, tmp2, order, ctx) == 0)
231
			goto err;
232
	} while (BN_is_zero(s));
233
	ok = 1;
234
235
err:
236
	EC_POINT_free(C);
237
	if (ctx != NULL) {
238
		BN_CTX_end(ctx);
239
		BN_CTX_free(ctx);
240
	}
241
	if (ok == 0) {
242
		ECDSA_SIG_free(newsig);
243
		newsig = NULL;
244
	}
245
	return newsig;
246
}
247
248
int
249
gost2001_do_verify(BIGNUM *md, ECDSA_SIG *sig, GOST_KEY *ec)
250
{
251
	BN_CTX *ctx = BN_CTX_new();
252
	const EC_GROUP *group = GOST_KEY_get0_group(ec);
253
	BIGNUM *order;
254
	BIGNUM *e = NULL, *R = NULL, *v = NULL, *z1 = NULL, *z2 = NULL;
255
	BIGNUM *X = NULL, *tmp = NULL;
256
	EC_POINT *C = NULL;
257
	const EC_POINT *pub_key = NULL;
258
	int ok = 0;
259
260
	if (ctx == NULL)
261
		goto err;
262
	BN_CTX_start(ctx);
263
	if ((order = BN_CTX_get(ctx)) == NULL)
264
		goto err;
265
	if ((e = BN_CTX_get(ctx)) == NULL)
266
		goto err;
267
	if ((z1 = BN_CTX_get(ctx)) == NULL)
268
		goto err;
269
	if ((z2 = BN_CTX_get(ctx)) == NULL)
270
		goto err;
271
	if ((tmp = BN_CTX_get(ctx)) == NULL)
272
		goto err;
273
	if ((X = BN_CTX_get(ctx)) == NULL)
274
		goto err;
275
	if ((R = BN_CTX_get(ctx)) == NULL)
276
		goto err;
277
	if ((v = BN_CTX_get(ctx)) == NULL)
278
		goto err;
279
280
	if (EC_GROUP_get_order(group, order, ctx) == 0)
281
		goto err;
282
	pub_key = GOST_KEY_get0_public_key(ec);
283
	if (BN_is_zero(sig->s) || BN_is_zero(sig->r) ||
284
	    BN_cmp(sig->s, order) >= 1 || BN_cmp(sig->r, order) >= 1) {
285
		GOSTerror(GOST_R_SIGNATURE_PARTS_GREATER_THAN_Q);
286
		goto err;
287
	}
288
289
	if (BN_mod_ct(e, md, order, ctx) == 0)
290
		goto err;
291
	if (BN_is_zero(e))
292
		BN_one(e);
293
	if ((v = BN_mod_inverse_ct(v, e, order, ctx)) == NULL)
294
		goto err;
295
	if (BN_mod_mul(z1, sig->s, v, order, ctx) == 0)
296
		goto err;
297
	if (BN_sub(tmp, order, sig->r) == 0)
298
		goto err;
299
	if (BN_mod_mul(z2, tmp, v, order, ctx) == 0)
300
		goto err;
301
	if ((C = EC_POINT_new(group)) == NULL)
302
		goto err;
303
	if (EC_POINT_mul(group, C, z1, pub_key, z2, ctx) == 0) {
304
		GOSTerror(ERR_R_EC_LIB);
305
		goto err;
306
	}
307
	if (EC_POINT_get_affine_coordinates_GFp(group, C, X, NULL, ctx) == 0) {
308
		GOSTerror(ERR_R_EC_LIB);
309
		goto err;
310
	}
311
	if (BN_mod_ct(R, X, order, ctx) == 0)
312
		goto err;
313
	if (BN_cmp(R, sig->r) != 0) {
314
		GOSTerror(GOST_R_SIGNATURE_MISMATCH);
315
	} else {
316
		ok = 1;
317
	}
318
err:
319
	EC_POINT_free(C);
320
	if (ctx != NULL) {
321
		BN_CTX_end(ctx);
322
		BN_CTX_free(ctx);
323
	}
324
	return ok;
325
}
326
327
/* Implementation of CryptoPro VKO 34.10-2001 algorithm */
328
int
329
VKO_compute_key(BIGNUM *X, BIGNUM *Y, const GOST_KEY *pkey, GOST_KEY *priv_key,
330
    const BIGNUM *ukm)
331
{
332
	BIGNUM *p = NULL, *order = NULL;
333
	const BIGNUM *key = GOST_KEY_get0_private_key(priv_key);
334
	const EC_GROUP *group = GOST_KEY_get0_group(priv_key);
335
	const EC_POINT *pub_key = GOST_KEY_get0_public_key(pkey);
336
	EC_POINT *pnt;
337
	BN_CTX *ctx = NULL;
338
	int ok = 0;
339
340
	pnt = EC_POINT_new(group);
341
	if (pnt == NULL)
342
		goto err;
343
	ctx = BN_CTX_new();
344
	if (ctx == NULL)
345
		goto err;
346
	BN_CTX_start(ctx);
347
	if ((p = BN_CTX_get(ctx)) == NULL)
348
		goto err;
349
	if ((order = BN_CTX_get(ctx)) == NULL)
350
		goto err;
351
	if (EC_GROUP_get_order(group, order, ctx) == 0)
352
		goto err;
353
	if (BN_mod_mul(p, key, ukm, order, ctx) == 0)
354
		goto err;
355
	if (EC_POINT_mul(group, pnt, NULL, pub_key, p, ctx) == 0)
356
		goto err;
357
	if (EC_POINT_get_affine_coordinates_GFp(group, pnt, X, Y, ctx) == 0)
358
		goto err;
359
	ok = 1;
360
361
err:
362
	if (ctx != NULL) {
363
		BN_CTX_end(ctx);
364
		BN_CTX_free(ctx);
365
	}
366
	EC_POINT_free(pnt);
367
	return ok;
368
}
369
370
int
371
gost2001_keygen(GOST_KEY *ec)
372
{
373
	BIGNUM *order = BN_new(), *d = BN_new();
374
	const EC_GROUP *group = GOST_KEY_get0_group(ec);
375
	int rc = 0;
376
377
	if (order == NULL || d == NULL)
378
		goto err;
379
	if (EC_GROUP_get_order(group, order, NULL) == 0)
380
		goto err;
381
382
	do {
383
		if (BN_rand_range(d, order) == 0) {
384
			GOSTerror(GOST_R_RANDOM_NUMBER_GENERATOR_FAILED);
385
			goto err;
386
		}
387
	} while (BN_is_zero(d));
388
389
	if (GOST_KEY_set_private_key(ec, d) == 0)
390
		goto err;
391
	rc = gost2001_compute_public(ec);
392
393
err:
394
	BN_free(d);
395
	BN_free(order);
396
	return rc;
397
}
398
#endif