1 /* $OpenBSD: ecp_mont.c,v 1.17 2018/11/05 20:18:21 tb Exp $ */ 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 #include "ec_lcl.h" 67 68 69 const EC_METHOD * 70 EC_GFp_mont_method(void) 71 { 72 static const EC_METHOD ret = { 73 .flags = EC_FLAGS_DEFAULT_OCT, 74 .field_type = NID_X9_62_prime_field, 75 .group_init = ec_GFp_mont_group_init, 76 .group_finish = ec_GFp_mont_group_finish, 77 .group_clear_finish = ec_GFp_mont_group_clear_finish, 78 .group_copy = ec_GFp_mont_group_copy, 79 .group_set_curve = ec_GFp_mont_group_set_curve, 80 .group_get_curve = ec_GFp_simple_group_get_curve, 81 .group_get_degree = ec_GFp_simple_group_get_degree, 82 .group_check_discriminant = 83 ec_GFp_simple_group_check_discriminant, 84 .point_init = ec_GFp_simple_point_init, 85 .point_finish = ec_GFp_simple_point_finish, 86 .point_clear_finish = ec_GFp_simple_point_clear_finish, 87 .point_copy = ec_GFp_simple_point_copy, 88 .point_set_to_infinity = ec_GFp_simple_point_set_to_infinity, 89 .point_set_Jprojective_coordinates_GFp = 90 ec_GFp_simple_set_Jprojective_coordinates_GFp, 91 .point_get_Jprojective_coordinates_GFp = 92 ec_GFp_simple_get_Jprojective_coordinates_GFp, 93 .point_set_affine_coordinates = 94 ec_GFp_simple_point_set_affine_coordinates, 95 .point_get_affine_coordinates = 96 ec_GFp_simple_point_get_affine_coordinates, 97 .add = ec_GFp_simple_add, 98 .dbl = ec_GFp_simple_dbl, 99 .invert = ec_GFp_simple_invert, 100 .is_at_infinity = ec_GFp_simple_is_at_infinity, 101 .is_on_curve = ec_GFp_simple_is_on_curve, 102 .point_cmp = ec_GFp_simple_cmp, 103 .make_affine = ec_GFp_simple_make_affine, 104 .points_make_affine = ec_GFp_simple_points_make_affine, 105 .mul_generator_ct = ec_GFp_simple_mul_generator_ct, 106 .mul_single_ct = ec_GFp_simple_mul_single_ct, 107 .mul_double_nonct = ec_GFp_simple_mul_double_nonct, 108 .field_mul = ec_GFp_mont_field_mul, 109 .field_sqr = ec_GFp_mont_field_sqr, 110 .field_encode = ec_GFp_mont_field_encode, 111 .field_decode = ec_GFp_mont_field_decode, 112 .field_set_to_one = ec_GFp_mont_field_set_to_one, 113 .blind_coordinates = ec_GFp_simple_blind_coordinates, 114 }; 115 116 return &ret; 117 } 118 119 120 int 121 ec_GFp_mont_group_init(EC_GROUP * group) 122 { 123 int ok; 124 125 ok = ec_GFp_simple_group_init(group); 126 group->field_data1 = NULL; 127 group->field_data2 = NULL; 128 return ok; 129 } 130 131 132 void 133 ec_GFp_mont_group_finish(EC_GROUP * group) 134 { 135 BN_MONT_CTX_free(group->field_data1); 136 group->field_data1 = NULL; 137 BN_free(group->field_data2); 138 group->field_data2 = NULL; 139 ec_GFp_simple_group_finish(group); 140 } 141 142 143 void 144 ec_GFp_mont_group_clear_finish(EC_GROUP * group) 145 { 146 BN_MONT_CTX_free(group->field_data1); 147 group->field_data1 = NULL; 148 BN_clear_free(group->field_data2); 149 group->field_data2 = NULL; 150 ec_GFp_simple_group_clear_finish(group); 151 } 152 153 154 int 155 ec_GFp_mont_group_copy(EC_GROUP * dest, const EC_GROUP * src) 156 { 157 BN_MONT_CTX_free(dest->field_data1); 158 dest->field_data1 = NULL; 159 BN_clear_free(dest->field_data2); 160 dest->field_data2 = NULL; 161 162 if (!ec_GFp_simple_group_copy(dest, src)) 163 return 0; 164 165 if (src->field_data1 != NULL) { 166 dest->field_data1 = BN_MONT_CTX_new(); 167 if (dest->field_data1 == NULL) 168 return 0; 169 if (!BN_MONT_CTX_copy(dest->field_data1, src->field_data1)) 170 goto err; 171 } 172 if (src->field_data2 != NULL) { 173 dest->field_data2 = BN_dup(src->field_data2); 174 if (dest->field_data2 == NULL) 175 goto err; 176 } 177 return 1; 178 179 err: 180 if (dest->field_data1 != NULL) { 181 BN_MONT_CTX_free(dest->field_data1); 182 dest->field_data1 = NULL; 183 } 184 return 0; 185 } 186 187 188 int 189 ec_GFp_mont_group_set_curve(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a, 190 const BIGNUM *b, BN_CTX *ctx) 191 { 192 BN_CTX *new_ctx = NULL; 193 BN_MONT_CTX *mont = NULL; 194 BIGNUM *one = NULL; 195 int ret = 0; 196 197 BN_MONT_CTX_free(group->field_data1); 198 group->field_data1 = NULL; 199 BN_free(group->field_data2); 200 group->field_data2 = NULL; 201 if (ctx == NULL) { 202 ctx = new_ctx = BN_CTX_new(); 203 if (ctx == NULL) 204 return 0; 205 } 206 mont = BN_MONT_CTX_new(); 207 if (mont == NULL) 208 goto err; 209 if (!BN_MONT_CTX_set(mont, p, ctx)) { 210 ECerror(ERR_R_BN_LIB); 211 goto err; 212 } 213 one = BN_new(); 214 if (one == NULL) 215 goto err; 216 if (!BN_to_montgomery(one, BN_value_one(), mont, ctx)) 217 goto err; 218 219 group->field_data1 = mont; 220 mont = NULL; 221 group->field_data2 = one; 222 one = NULL; 223 224 ret = ec_GFp_simple_group_set_curve(group, p, a, b, ctx); 225 226 if (!ret) { 227 BN_MONT_CTX_free(group->field_data1); 228 group->field_data1 = NULL; 229 BN_free(group->field_data2); 230 group->field_data2 = NULL; 231 } 232 err: 233 BN_CTX_free(new_ctx); 234 BN_MONT_CTX_free(mont); 235 BN_free(one); 236 return ret; 237 } 238 239 240 int 241 ec_GFp_mont_field_mul(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, 242 const BIGNUM *b, BN_CTX *ctx) 243 { 244 if (group->field_data1 == NULL) { 245 ECerror(EC_R_NOT_INITIALIZED); 246 return 0; 247 } 248 return BN_mod_mul_montgomery(r, a, b, group->field_data1, ctx); 249 } 250 251 252 int 253 ec_GFp_mont_field_sqr(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, 254 BN_CTX *ctx) 255 { 256 if (group->field_data1 == NULL) { 257 ECerror(EC_R_NOT_INITIALIZED); 258 return 0; 259 } 260 return BN_mod_mul_montgomery(r, a, a, group->field_data1, ctx); 261 } 262 263 264 int 265 ec_GFp_mont_field_encode(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, 266 BN_CTX *ctx) 267 { 268 if (group->field_data1 == NULL) { 269 ECerror(EC_R_NOT_INITIALIZED); 270 return 0; 271 } 272 return BN_to_montgomery(r, a, (BN_MONT_CTX *) group->field_data1, ctx); 273 } 274 275 276 int 277 ec_GFp_mont_field_decode(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, 278 BN_CTX *ctx) 279 { 280 if (group->field_data1 == NULL) { 281 ECerror(EC_R_NOT_INITIALIZED); 282 return 0; 283 } 284 return BN_from_montgomery(r, a, group->field_data1, ctx); 285 } 286 287 288 int 289 ec_GFp_mont_field_set_to_one(const EC_GROUP *group, BIGNUM *r, BN_CTX *ctx) 290 { 291 if (group->field_data2 == NULL) { 292 ECerror(EC_R_NOT_INITIALIZED); 293 return 0; 294 } 295 if (!BN_copy(r, group->field_data2)) 296 return 0; 297 return 1; 298 } 299