ecp_mont.c revision 04ef91b390dfcc6125913e2f2af502d23d7a5112 
1/* crypto/ec/ecp_mont.c */
2/*
3 * Originally written by Bodo Moeller for the OpenSSL project.
4 */
5/* ====================================================================
6 * Copyright (c) 1998-2001 The OpenSSL Project.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in
17 *    the documentation and/or other materials provided with the
18 *    distribution.
19 *
20 * 3. All advertising materials mentioning features or use of this
21 *    software must display the following acknowledgment:
22 *    "This product includes software developed by the OpenSSL Project
23 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
24 *
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 *    endorse or promote products derived from this software without
27 *    prior written permission. For written permission, please contact
28 *    openssl-core@openssl.org.
29 *
30 * 5. Products derived from this software may not be called "OpenSSL"
31 *    nor may "OpenSSL" appear in their names without prior written
32 *    permission of the OpenSSL Project.
33 *
34 * 6. Redistributions of any form whatsoever must retain the following
35 *    acknowledgment:
36 *    "This product includes software developed by the OpenSSL Project
37 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
38 *
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
52 *
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com).  This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
56 *
57 */
58/* ====================================================================
59 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
60 * Portions of this software developed by SUN MICROSYSTEMS, INC.,
61 * and contributed to the OpenSSL project.
62 */
63
64#include <openssl/err.h>
65
66#ifdef OPENSSL_FIPS
67#include <openssl/fips.h>
68#endif
69
70#include "ec_lcl.h"
71
72
73const EC_METHOD *EC_GFp_mont_method(void)
74	{
75#ifdef OPENSSL_FIPS
76	return fips_ec_gfp_mont_method();
77#else
78	static const EC_METHOD ret = {
79		EC_FLAGS_DEFAULT_OCT,
80		NID_X9_62_prime_field,
81		ec_GFp_mont_group_init,
82		ec_GFp_mont_group_finish,
83		ec_GFp_mont_group_clear_finish,
84		ec_GFp_mont_group_copy,
85		ec_GFp_mont_group_set_curve,
86		ec_GFp_simple_group_get_curve,
87		ec_GFp_simple_group_get_degree,
88		ec_GFp_simple_group_check_discriminant,
89		ec_GFp_simple_point_init,
90		ec_GFp_simple_point_finish,
91		ec_GFp_simple_point_clear_finish,
92		ec_GFp_simple_point_copy,
93		ec_GFp_simple_point_set_to_infinity,
94		ec_GFp_simple_set_Jprojective_coordinates_GFp,
95		ec_GFp_simple_get_Jprojective_coordinates_GFp,
96		ec_GFp_simple_point_set_affine_coordinates,
97		ec_GFp_simple_point_get_affine_coordinates,
98		0,0,0,
99		ec_GFp_simple_add,
100		ec_GFp_simple_dbl,
101		ec_GFp_simple_invert,
102		ec_GFp_simple_is_at_infinity,
103		ec_GFp_simple_is_on_curve,
104		ec_GFp_simple_cmp,
105		ec_GFp_simple_make_affine,
106		ec_GFp_simple_points_make_affine,
107		0 /* mul */,
108		0 /* precompute_mult */,
109		0 /* have_precompute_mult */,
110		ec_GFp_mont_field_mul,
111		ec_GFp_mont_field_sqr,
112		0 /* field_div */,
113		ec_GFp_mont_field_encode,
114		ec_GFp_mont_field_decode,
115		ec_GFp_mont_field_set_to_one };
116
117	return &ret;
118#endif
119	}
120
121
122int ec_GFp_mont_group_init(EC_GROUP *group)
123	{
124	int ok;
125
126	ok = ec_GFp_simple_group_init(group);
127	group->field_data1 = NULL;
128	group->field_data2 = NULL;
129	return ok;
130	}
131
132
133void ec_GFp_mont_group_finish(EC_GROUP *group)
134	{
135	if (group->field_data1 != NULL)
136		{
137		BN_MONT_CTX_free(group->field_data1);
138		group->field_data1 = NULL;
139		}
140	if (group->field_data2 != NULL)
141		{
142		BN_free(group->field_data2);
143		group->field_data2 = NULL;
144		}
145	ec_GFp_simple_group_finish(group);
146	}
147
148
149void ec_GFp_mont_group_clear_finish(EC_GROUP *group)
150	{
151	if (group->field_data1 != NULL)
152		{
153		BN_MONT_CTX_free(group->field_data1);
154		group->field_data1 = NULL;
155		}
156	if (group->field_data2 != NULL)
157		{
158		BN_clear_free(group->field_data2);
159		group->field_data2 = NULL;
160		}
161	ec_GFp_simple_group_clear_finish(group);
162	}
163
164
165int ec_GFp_mont_group_copy(EC_GROUP *dest, const EC_GROUP *src)
166	{
167	if (dest->field_data1 != NULL)
168		{
169		BN_MONT_CTX_free(dest->field_data1);
170		dest->field_data1 = NULL;
171		}
172	if (dest->field_data2 != NULL)
173		{
174		BN_clear_free(dest->field_data2);
175		dest->field_data2 = NULL;
176		}
177
178	if (!ec_GFp_simple_group_copy(dest, src)) return 0;
179
180	if (src->field_data1 != NULL)
181		{
182		dest->field_data1 = BN_MONT_CTX_new();
183		if (dest->field_data1 == NULL) return 0;
184		if (!BN_MONT_CTX_copy(dest->field_data1, src->field_data1)) goto err;
185		}
186	if (src->field_data2 != NULL)
187		{
188		dest->field_data2 = BN_dup(src->field_data2);
189		if (dest->field_data2 == NULL) goto err;
190		}
191
192	return 1;
193
194 err:
195	if (dest->field_data1 != NULL)
196		{
197		BN_MONT_CTX_free(dest->field_data1);
198		dest->field_data1 = NULL;
199		}
200	return 0;
201	}
202
203
204int ec_GFp_mont_group_set_curve(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx)
205	{
206	BN_CTX *new_ctx = NULL;
207	BN_MONT_CTX *mont = NULL;
208	BIGNUM *one = NULL;
209	int ret = 0;
210
211	if (group->field_data1 != NULL)
212		{
213		BN_MONT_CTX_free(group->field_data1);
214		group->field_data1 = NULL;
215		}
216	if (group->field_data2 != NULL)
217		{
218		BN_free(group->field_data2);
219		group->field_data2 = NULL;
220		}
221
222	if (ctx == NULL)
223		{
224		ctx = new_ctx = BN_CTX_new();
225		if (ctx == NULL)
226			return 0;
227		}
228
229	mont = BN_MONT_CTX_new();
230	if (mont == NULL) goto err;
231	if (!BN_MONT_CTX_set(mont, p, ctx))
232		{
233		ECerr(EC_F_EC_GFP_MONT_GROUP_SET_CURVE, ERR_R_BN_LIB);
234		goto err;
235		}
236	one = BN_new();
237	if (one == NULL) goto err;
238	if (!BN_to_montgomery(one, BN_value_one(), mont, ctx)) goto err;
239
240	group->field_data1 = mont;
241	mont = NULL;
242	group->field_data2 = one;
243	one = NULL;
244
245	ret = ec_GFp_simple_group_set_curve(group, p, a, b, ctx);
246
247	if (!ret)
248		{
249		BN_MONT_CTX_free(group->field_data1);
250		group->field_data1 = NULL;
251		BN_free(group->field_data2);
252		group->field_data2 = NULL;
253		}
254
255 err:
256	if (new_ctx != NULL)
257		BN_CTX_free(new_ctx);
258	if (mont != NULL)
259		BN_MONT_CTX_free(mont);
260	return ret;
261	}
262
263
264int ec_GFp_mont_field_mul(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx)
265	{
266	if (group->field_data1 == NULL)
267		{
268		ECerr(EC_F_EC_GFP_MONT_FIELD_MUL, EC_R_NOT_INITIALIZED);
269		return 0;
270		}
271
272	return BN_mod_mul_montgomery(r, a, b, group->field_data1, ctx);
273	}
274
275
276int ec_GFp_mont_field_sqr(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, BN_CTX *ctx)
277	{
278	if (group->field_data1 == NULL)
279		{
280		ECerr(EC_F_EC_GFP_MONT_FIELD_SQR, EC_R_NOT_INITIALIZED);
281		return 0;
282		}
283
284	return BN_mod_mul_montgomery(r, a, a, group->field_data1, ctx);
285	}
286
287
288int ec_GFp_mont_field_encode(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, BN_CTX *ctx)
289	{
290	if (group->field_data1 == NULL)
291		{
292		ECerr(EC_F_EC_GFP_MONT_FIELD_ENCODE, EC_R_NOT_INITIALIZED);
293		return 0;
294		}
295
296	return BN_to_montgomery(r, a, (BN_MONT_CTX *)group->field_data1, ctx);
297	}
298
299
300int ec_GFp_mont_field_decode(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, BN_CTX *ctx)
301	{
302	if (group->field_data1 == NULL)
303		{
304		ECerr(EC_F_EC_GFP_MONT_FIELD_DECODE, EC_R_NOT_INITIALIZED);
305		return 0;
306		}
307
308	return BN_from_montgomery(r, a, group->field_data1, ctx);
309	}
310
311
312int ec_GFp_mont_field_set_to_one(const EC_GROUP *group, BIGNUM *r, BN_CTX *ctx)
313	{
314	if (group->field_data2 == NULL)
315		{
316		ECerr(EC_F_EC_GFP_MONT_FIELD_SET_TO_ONE, EC_R_NOT_INITIALIZED);
317		return 0;
318		}
319
320	if (!BN_copy(r, group->field_data2)) return 0;
321	return 1;
322	}
323