1 /* Originally written by Bodo Moeller and Nils Larsch for the OpenSSL project.
2 * ====================================================================
3 * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in
14 * the documentation and/or other materials provided with the
15 * distribution.
16 *
17 * 3. All advertising materials mentioning features or use of this
18 * software must display the following acknowledgment:
19 * "This product includes software developed by the OpenSSL Project
20 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
21 *
22 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
23 * endorse or promote products derived from this software without
24 * prior written permission. For written permission, please contact
25 * openssl-core@openssl.org.
26 *
27 * 5. Products derived from this software may not be called "OpenSSL"
28 * nor may "OpenSSL" appear in their names without prior written
29 * permission of the OpenSSL Project.
30 *
31 * 6. Redistributions of any form whatsoever must retain the following
32 * acknowledgment:
33 * "This product includes software developed by the OpenSSL Project
34 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
35 *
36 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
37 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
39 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
40 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
42 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
43 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
44 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
45 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
46 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
47 * OF THE POSSIBILITY OF SUCH DAMAGE.
48 * ====================================================================
49 *
50 * This product includes cryptographic software written by Eric Young
51 * (eay@cryptsoft.com). This product includes software written by Tim
52 * Hudson (tjh@cryptsoft.com).
53 *
54 */
55 /* ====================================================================
56 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
57 *
58 * Portions of the attached software ("Contribution") are developed by
59 * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
60 *
61 * The Contribution is licensed pursuant to the OpenSSL open source
62 * license provided above.
63 *
64 * The elliptic curve binary polynomial software is originally written by
65 * Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems
66 * Laboratories. */
67
68 #include <openssl/ec.h>
69
70 #include <openssl/bn.h>
71 #include <openssl/err.h>
72 #include <openssl/mem.h>
73
74 #include "internal.h"
75
76
EC_GFp_mont_method(void)77 const EC_METHOD *EC_GFp_mont_method(void) {
78 static const EC_METHOD ret = {EC_FLAGS_DEFAULT_OCT,
79 ec_GFp_mont_group_init,
80 ec_GFp_mont_group_finish,
81 ec_GFp_mont_group_clear_finish,
82 ec_GFp_mont_group_copy,
83 ec_GFp_mont_group_set_curve,
84 ec_GFp_simple_group_get_curve,
85 ec_GFp_simple_group_get_degree,
86 ec_GFp_simple_group_check_discriminant,
87 ec_GFp_simple_point_init,
88 ec_GFp_simple_point_finish,
89 ec_GFp_simple_point_clear_finish,
90 ec_GFp_simple_point_copy,
91 ec_GFp_simple_point_set_to_infinity,
92 ec_GFp_simple_set_Jprojective_coordinates_GFp,
93 ec_GFp_simple_get_Jprojective_coordinates_GFp,
94 ec_GFp_simple_point_set_affine_coordinates,
95 ec_GFp_simple_point_get_affine_coordinates,
96 0,
97 0,
98 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 }
119
ec_GFp_mont_group_init(EC_GROUP * group)120 int ec_GFp_mont_group_init(EC_GROUP *group) {
121 int ok;
122
123 ok = ec_GFp_simple_group_init(group);
124 group->mont = NULL;
125 group->one = NULL;
126 return ok;
127 }
128
ec_GFp_mont_group_finish(EC_GROUP * group)129 void ec_GFp_mont_group_finish(EC_GROUP *group) {
130 BN_MONT_CTX_free(group->mont);
131 group->mont = NULL;
132 BN_free(group->one);
133 group->one = NULL;
134 ec_GFp_simple_group_finish(group);
135 }
136
ec_GFp_mont_group_clear_finish(EC_GROUP * group)137 void ec_GFp_mont_group_clear_finish(EC_GROUP *group) {
138 BN_MONT_CTX_free(group->mont);
139 group->mont = NULL;
140 BN_clear_free(group->one);
141 group->one = NULL;
142 ec_GFp_simple_group_clear_finish(group);
143 }
144
ec_GFp_mont_group_copy(EC_GROUP * dest,const EC_GROUP * src)145 int ec_GFp_mont_group_copy(EC_GROUP *dest, const EC_GROUP *src) {
146 BN_MONT_CTX_free(dest->mont);
147 dest->mont = NULL;
148 BN_clear_free(dest->one);
149 dest->one = NULL;
150
151 if (!ec_GFp_simple_group_copy(dest, src)) {
152 return 0;
153 }
154
155 if (src->mont != NULL) {
156 dest->mont = BN_MONT_CTX_new();
157 if (dest->mont == NULL) {
158 return 0;
159 }
160 if (!BN_MONT_CTX_copy(dest->mont, src->mont)) {
161 goto err;
162 }
163 }
164 if (src->one != NULL) {
165 dest->one = BN_dup(src->one);
166 if (dest->one == NULL) {
167 goto err;
168 }
169 }
170
171 return 1;
172
173 err:
174 BN_MONT_CTX_free(dest->mont);
175 dest->mont = NULL;
176 return 0;
177 }
178
ec_GFp_mont_group_set_curve(EC_GROUP * group,const BIGNUM * p,const BIGNUM * a,const BIGNUM * b,BN_CTX * ctx)179 int ec_GFp_mont_group_set_curve(EC_GROUP *group, const BIGNUM *p,
180 const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx) {
181 BN_CTX *new_ctx = NULL;
182 BN_MONT_CTX *mont = NULL;
183 BIGNUM *one = NULL;
184 int ret = 0;
185
186 BN_MONT_CTX_free(group->mont);
187 group->mont = NULL;
188 BN_free(group->one);
189 group->one = NULL;
190
191 if (ctx == NULL) {
192 ctx = new_ctx = BN_CTX_new();
193 if (ctx == NULL) {
194 return 0;
195 }
196 }
197
198 mont = BN_MONT_CTX_new();
199 if (mont == NULL) {
200 goto err;
201 }
202 if (!BN_MONT_CTX_set(mont, p, ctx)) {
203 OPENSSL_PUT_ERROR(EC, ec_GFp_mont_group_set_curve, ERR_R_BN_LIB);
204 goto err;
205 }
206 one = BN_new();
207 if (one == NULL || !BN_to_montgomery(one, BN_value_one(), mont, ctx)) {
208 goto err;
209 }
210
211 group->mont = mont;
212 mont = NULL;
213 group->one = one;
214 one = NULL;
215
216 ret = ec_GFp_simple_group_set_curve(group, p, a, b, ctx);
217
218 if (!ret) {
219 BN_MONT_CTX_free(group->mont);
220 group->mont = NULL;
221 BN_free(group->one);
222 group->one = NULL;
223 }
224
225 err:
226 BN_CTX_free(new_ctx);
227 BN_MONT_CTX_free(mont);
228 BN_free(one);
229 return ret;
230 }
231
ec_GFp_mont_field_mul(const EC_GROUP * group,BIGNUM * r,const BIGNUM * a,const BIGNUM * b,BN_CTX * ctx)232 int ec_GFp_mont_field_mul(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a,
233 const BIGNUM *b, BN_CTX *ctx) {
234 if (group->mont == NULL) {
235 OPENSSL_PUT_ERROR(EC, ec_GFp_mont_field_mul, EC_R_NOT_INITIALIZED);
236 return 0;
237 }
238
239 return BN_mod_mul_montgomery(r, a, b, group->mont, ctx);
240 }
241
ec_GFp_mont_field_sqr(const EC_GROUP * group,BIGNUM * r,const BIGNUM * a,BN_CTX * ctx)242 int ec_GFp_mont_field_sqr(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a,
243 BN_CTX *ctx) {
244 if (group->mont == NULL) {
245 OPENSSL_PUT_ERROR(EC, ec_GFp_mont_field_sqr, EC_R_NOT_INITIALIZED);
246 return 0;
247 }
248
249 return BN_mod_mul_montgomery(r, a, a, group->mont, ctx);
250 }
251
ec_GFp_mont_field_encode(const EC_GROUP * group,BIGNUM * r,const BIGNUM * a,BN_CTX * ctx)252 int ec_GFp_mont_field_encode(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a,
253 BN_CTX *ctx) {
254 if (group->mont == NULL) {
255 OPENSSL_PUT_ERROR(EC, ec_GFp_mont_field_encode, EC_R_NOT_INITIALIZED);
256 return 0;
257 }
258
259 return BN_to_montgomery(r, a, group->mont, ctx);
260 }
261
ec_GFp_mont_field_decode(const EC_GROUP * group,BIGNUM * r,const BIGNUM * a,BN_CTX * ctx)262 int ec_GFp_mont_field_decode(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a,
263 BN_CTX *ctx) {
264 if (group->mont == NULL) {
265 OPENSSL_PUT_ERROR(EC, ec_GFp_mont_field_decode, EC_R_NOT_INITIALIZED);
266 return 0;
267 }
268
269 return BN_from_montgomery(r, a, group->mont, ctx);
270 }
271
ec_GFp_mont_field_set_to_one(const EC_GROUP * group,BIGNUM * r,BN_CTX * ctx)272 int ec_GFp_mont_field_set_to_one(const EC_GROUP *group, BIGNUM *r,
273 BN_CTX *ctx) {
274 if (group->one == NULL) {
275 OPENSSL_PUT_ERROR(EC, ec_GFp_mont_field_set_to_one, EC_R_NOT_INITIALIZED);
276 return 0;
277 }
278
279 if (!BN_copy(r, group->one)) {
280 return 0;
281 }
282 return 1;
283 }
284