Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 1 | /* crypto/ec/ec2_smpl.c */ |
| 2 | /* ==================================================================== |
| 3 | * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. |
| 4 | * |
| 5 | * The Elliptic Curve Public-Key Crypto Library (ECC Code) included |
| 6 | * herein is developed by SUN MICROSYSTEMS, INC., and is contributed |
| 7 | * to the OpenSSL project. |
| 8 | * |
| 9 | * The ECC Code is licensed pursuant to the OpenSSL open source |
| 10 | * license provided below. |
| 11 | * |
| 12 | * The software is originally written by Sheueling Chang Shantz and |
| 13 | * Douglas Stebila of Sun Microsystems Laboratories. |
| 14 | * |
| 15 | */ |
| 16 | /* ==================================================================== |
| 17 | * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved. |
| 18 | * |
| 19 | * Redistribution and use in source and binary forms, with or without |
| 20 | * modification, are permitted provided that the following conditions |
| 21 | * are met: |
| 22 | * |
| 23 | * 1. Redistributions of source code must retain the above copyright |
| 24 | * notice, this list of conditions and the following disclaimer. |
| 25 | * |
| 26 | * 2. Redistributions in binary form must reproduce the above copyright |
| 27 | * notice, this list of conditions and the following disclaimer in |
| 28 | * the documentation and/or other materials provided with the |
| 29 | * distribution. |
| 30 | * |
| 31 | * 3. All advertising materials mentioning features or use of this |
| 32 | * software must display the following acknowledgment: |
| 33 | * "This product includes software developed by the OpenSSL Project |
| 34 | * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" |
| 35 | * |
| 36 | * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to |
| 37 | * endorse or promote products derived from this software without |
| 38 | * prior written permission. For written permission, please contact |
| 39 | * openssl-core@openssl.org. |
| 40 | * |
| 41 | * 5. Products derived from this software may not be called "OpenSSL" |
| 42 | * nor may "OpenSSL" appear in their names without prior written |
| 43 | * permission of the OpenSSL Project. |
| 44 | * |
| 45 | * 6. Redistributions of any form whatsoever must retain the following |
| 46 | * acknowledgment: |
| 47 | * "This product includes software developed by the OpenSSL Project |
| 48 | * for use in the OpenSSL Toolkit (http://www.openssl.org/)" |
| 49 | * |
| 50 | * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY |
| 51 | * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 52 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 53 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR |
| 54 | * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 55 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 56 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| 57 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 58 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| 59 | * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 60 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
| 61 | * OF THE POSSIBILITY OF SUCH DAMAGE. |
| 62 | * ==================================================================== |
| 63 | * |
| 64 | * This product includes cryptographic software written by Eric Young |
| 65 | * (eay@cryptsoft.com). This product includes software written by Tim |
| 66 | * Hudson (tjh@cryptsoft.com). |
| 67 | * |
| 68 | */ |
| 69 | |
| 70 | #include <openssl/err.h> |
| 71 | |
| 72 | #include "ec_lcl.h" |
| 73 | |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 74 | |
| 75 | const EC_METHOD *EC_GF2m_simple_method(void) |
| 76 | { |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 77 | static const EC_METHOD ret = { |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 78 | NID_X9_62_characteristic_two_field, |
| 79 | ec_GF2m_simple_group_init, |
| 80 | ec_GF2m_simple_group_finish, |
| 81 | ec_GF2m_simple_group_clear_finish, |
| 82 | ec_GF2m_simple_group_copy, |
| 83 | ec_GF2m_simple_group_set_curve, |
| 84 | ec_GF2m_simple_group_get_curve, |
| 85 | ec_GF2m_simple_group_get_degree, |
| 86 | ec_GF2m_simple_group_check_discriminant, |
| 87 | ec_GF2m_simple_point_init, |
| 88 | ec_GF2m_simple_point_finish, |
| 89 | ec_GF2m_simple_point_clear_finish, |
| 90 | ec_GF2m_simple_point_copy, |
| 91 | ec_GF2m_simple_point_set_to_infinity, |
| 92 | 0 /* set_Jprojective_coordinates_GFp */, |
| 93 | 0 /* get_Jprojective_coordinates_GFp */, |
| 94 | ec_GF2m_simple_point_set_affine_coordinates, |
| 95 | ec_GF2m_simple_point_get_affine_coordinates, |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 96 | ec_GF2m_simple_set_compressed_coordinates, |
| 97 | ec_GF2m_simple_point2oct, |
| 98 | ec_GF2m_simple_oct2point, |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 99 | ec_GF2m_simple_add, |
| 100 | ec_GF2m_simple_dbl, |
| 101 | ec_GF2m_simple_invert, |
| 102 | ec_GF2m_simple_is_at_infinity, |
| 103 | ec_GF2m_simple_is_on_curve, |
| 104 | ec_GF2m_simple_cmp, |
| 105 | ec_GF2m_simple_make_affine, |
| 106 | ec_GF2m_simple_points_make_affine, |
| 107 | |
| 108 | /* the following three method functions are defined in ec2_mult.c */ |
| 109 | ec_GF2m_simple_mul, |
| 110 | ec_GF2m_precompute_mult, |
| 111 | ec_GF2m_have_precompute_mult, |
| 112 | |
| 113 | ec_GF2m_simple_field_mul, |
| 114 | ec_GF2m_simple_field_sqr, |
| 115 | ec_GF2m_simple_field_div, |
| 116 | 0 /* field_encode */, |
| 117 | 0 /* field_decode */, |
| 118 | 0 /* field_set_to_one */ }; |
| 119 | |
| 120 | return &ret; |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 121 | } |
| 122 | |
| 123 | |
| 124 | /* Initialize a GF(2^m)-based EC_GROUP structure. |
| 125 | * Note that all other members are handled by EC_GROUP_new. |
| 126 | */ |
| 127 | int ec_GF2m_simple_group_init(EC_GROUP *group) |
| 128 | { |
| 129 | BN_init(&group->field); |
| 130 | BN_init(&group->a); |
| 131 | BN_init(&group->b); |
| 132 | return 1; |
| 133 | } |
| 134 | |
| 135 | |
| 136 | /* Free a GF(2^m)-based EC_GROUP structure. |
| 137 | * Note that all other members are handled by EC_GROUP_free. |
| 138 | */ |
| 139 | void ec_GF2m_simple_group_finish(EC_GROUP *group) |
| 140 | { |
| 141 | BN_free(&group->field); |
| 142 | BN_free(&group->a); |
| 143 | BN_free(&group->b); |
| 144 | } |
| 145 | |
| 146 | |
| 147 | /* Clear and free a GF(2^m)-based EC_GROUP structure. |
| 148 | * Note that all other members are handled by EC_GROUP_clear_free. |
| 149 | */ |
| 150 | void ec_GF2m_simple_group_clear_finish(EC_GROUP *group) |
| 151 | { |
| 152 | BN_clear_free(&group->field); |
| 153 | BN_clear_free(&group->a); |
| 154 | BN_clear_free(&group->b); |
| 155 | group->poly[0] = 0; |
| 156 | group->poly[1] = 0; |
| 157 | group->poly[2] = 0; |
| 158 | group->poly[3] = 0; |
| 159 | group->poly[4] = 0; |
| 160 | group->poly[5] = -1; |
| 161 | } |
| 162 | |
| 163 | |
| 164 | /* Copy a GF(2^m)-based EC_GROUP structure. |
| 165 | * Note that all other members are handled by EC_GROUP_copy. |
| 166 | */ |
| 167 | int ec_GF2m_simple_group_copy(EC_GROUP *dest, const EC_GROUP *src) |
| 168 | { |
| 169 | int i; |
| 170 | if (!BN_copy(&dest->field, &src->field)) return 0; |
| 171 | if (!BN_copy(&dest->a, &src->a)) return 0; |
| 172 | if (!BN_copy(&dest->b, &src->b)) return 0; |
| 173 | dest->poly[0] = src->poly[0]; |
| 174 | dest->poly[1] = src->poly[1]; |
| 175 | dest->poly[2] = src->poly[2]; |
| 176 | dest->poly[3] = src->poly[3]; |
| 177 | dest->poly[4] = src->poly[4]; |
| 178 | dest->poly[5] = src->poly[5]; |
| 179 | if (bn_wexpand(&dest->a, (int)(dest->poly[0] + BN_BITS2 - 1) / BN_BITS2) == NULL) return 0; |
| 180 | if (bn_wexpand(&dest->b, (int)(dest->poly[0] + BN_BITS2 - 1) / BN_BITS2) == NULL) return 0; |
| 181 | for (i = dest->a.top; i < dest->a.dmax; i++) dest->a.d[i] = 0; |
| 182 | for (i = dest->b.top; i < dest->b.dmax; i++) dest->b.d[i] = 0; |
| 183 | return 1; |
| 184 | } |
| 185 | |
| 186 | |
| 187 | /* Set the curve parameters of an EC_GROUP structure. */ |
| 188 | int ec_GF2m_simple_group_set_curve(EC_GROUP *group, |
| 189 | const BIGNUM *p, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx) |
| 190 | { |
| 191 | int ret = 0, i; |
| 192 | |
| 193 | /* group->field */ |
| 194 | if (!BN_copy(&group->field, p)) goto err; |
| 195 | i = BN_GF2m_poly2arr(&group->field, group->poly, 6) - 1; |
| 196 | if ((i != 5) && (i != 3)) |
| 197 | { |
| 198 | ECerr(EC_F_EC_GF2M_SIMPLE_GROUP_SET_CURVE, EC_R_UNSUPPORTED_FIELD); |
| 199 | goto err; |
| 200 | } |
| 201 | |
| 202 | /* group->a */ |
| 203 | if (!BN_GF2m_mod_arr(&group->a, a, group->poly)) goto err; |
| 204 | if(bn_wexpand(&group->a, (int)(group->poly[0] + BN_BITS2 - 1) / BN_BITS2) == NULL) goto err; |
| 205 | for (i = group->a.top; i < group->a.dmax; i++) group->a.d[i] = 0; |
| 206 | |
| 207 | /* group->b */ |
| 208 | if (!BN_GF2m_mod_arr(&group->b, b, group->poly)) goto err; |
| 209 | if(bn_wexpand(&group->b, (int)(group->poly[0] + BN_BITS2 - 1) / BN_BITS2) == NULL) goto err; |
| 210 | for (i = group->b.top; i < group->b.dmax; i++) group->b.d[i] = 0; |
| 211 | |
| 212 | ret = 1; |
| 213 | err: |
| 214 | return ret; |
| 215 | } |
| 216 | |
| 217 | |
| 218 | /* Get the curve parameters of an EC_GROUP structure. |
| 219 | * If p, a, or b are NULL then there values will not be set but the method will return with success. |
| 220 | */ |
| 221 | int ec_GF2m_simple_group_get_curve(const EC_GROUP *group, BIGNUM *p, BIGNUM *a, BIGNUM *b, BN_CTX *ctx) |
| 222 | { |
| 223 | int ret = 0; |
| 224 | |
| 225 | if (p != NULL) |
| 226 | { |
| 227 | if (!BN_copy(p, &group->field)) return 0; |
| 228 | } |
| 229 | |
| 230 | if (a != NULL) |
| 231 | { |
| 232 | if (!BN_copy(a, &group->a)) goto err; |
| 233 | } |
| 234 | |
| 235 | if (b != NULL) |
| 236 | { |
| 237 | if (!BN_copy(b, &group->b)) goto err; |
| 238 | } |
| 239 | |
| 240 | ret = 1; |
| 241 | |
| 242 | err: |
| 243 | return ret; |
| 244 | } |
| 245 | |
| 246 | |
| 247 | /* Gets the degree of the field. For a curve over GF(2^m) this is the value m. */ |
| 248 | int ec_GF2m_simple_group_get_degree(const EC_GROUP *group) |
| 249 | { |
| 250 | return BN_num_bits(&group->field)-1; |
| 251 | } |
| 252 | |
| 253 | |
| 254 | /* Checks the discriminant of the curve. |
| 255 | * y^2 + x*y = x^3 + a*x^2 + b is an elliptic curve <=> b != 0 (mod p) |
| 256 | */ |
| 257 | int ec_GF2m_simple_group_check_discriminant(const EC_GROUP *group, BN_CTX *ctx) |
| 258 | { |
| 259 | int ret = 0; |
| 260 | BIGNUM *b; |
| 261 | BN_CTX *new_ctx = NULL; |
| 262 | |
| 263 | if (ctx == NULL) |
| 264 | { |
| 265 | ctx = new_ctx = BN_CTX_new(); |
| 266 | if (ctx == NULL) |
| 267 | { |
| 268 | ECerr(EC_F_EC_GF2M_SIMPLE_GROUP_CHECK_DISCRIMINANT, ERR_R_MALLOC_FAILURE); |
| 269 | goto err; |
| 270 | } |
| 271 | } |
| 272 | BN_CTX_start(ctx); |
| 273 | b = BN_CTX_get(ctx); |
| 274 | if (b == NULL) goto err; |
| 275 | |
| 276 | if (!BN_GF2m_mod_arr(b, &group->b, group->poly)) goto err; |
| 277 | |
| 278 | /* check the discriminant: |
| 279 | * y^2 + x*y = x^3 + a*x^2 + b is an elliptic curve <=> b != 0 (mod p) |
| 280 | */ |
| 281 | if (BN_is_zero(b)) goto err; |
| 282 | |
| 283 | ret = 1; |
| 284 | |
| 285 | err: |
| 286 | if (ctx != NULL) |
| 287 | BN_CTX_end(ctx); |
| 288 | if (new_ctx != NULL) |
| 289 | BN_CTX_free(new_ctx); |
| 290 | return ret; |
| 291 | } |
| 292 | |
| 293 | |
| 294 | /* Initializes an EC_POINT. */ |
| 295 | int ec_GF2m_simple_point_init(EC_POINT *point) |
| 296 | { |
| 297 | BN_init(&point->X); |
| 298 | BN_init(&point->Y); |
| 299 | BN_init(&point->Z); |
| 300 | return 1; |
| 301 | } |
| 302 | |
| 303 | |
| 304 | /* Frees an EC_POINT. */ |
| 305 | void ec_GF2m_simple_point_finish(EC_POINT *point) |
| 306 | { |
| 307 | BN_free(&point->X); |
| 308 | BN_free(&point->Y); |
| 309 | BN_free(&point->Z); |
| 310 | } |
| 311 | |
| 312 | |
| 313 | /* Clears and frees an EC_POINT. */ |
| 314 | void ec_GF2m_simple_point_clear_finish(EC_POINT *point) |
| 315 | { |
| 316 | BN_clear_free(&point->X); |
| 317 | BN_clear_free(&point->Y); |
| 318 | BN_clear_free(&point->Z); |
| 319 | point->Z_is_one = 0; |
| 320 | } |
| 321 | |
| 322 | |
| 323 | /* Copy the contents of one EC_POINT into another. Assumes dest is initialized. */ |
| 324 | int ec_GF2m_simple_point_copy(EC_POINT *dest, const EC_POINT *src) |
| 325 | { |
| 326 | if (!BN_copy(&dest->X, &src->X)) return 0; |
| 327 | if (!BN_copy(&dest->Y, &src->Y)) return 0; |
| 328 | if (!BN_copy(&dest->Z, &src->Z)) return 0; |
| 329 | dest->Z_is_one = src->Z_is_one; |
| 330 | |
| 331 | return 1; |
| 332 | } |
| 333 | |
| 334 | |
| 335 | /* Set an EC_POINT to the point at infinity. |
| 336 | * A point at infinity is represented by having Z=0. |
| 337 | */ |
| 338 | int ec_GF2m_simple_point_set_to_infinity(const EC_GROUP *group, EC_POINT *point) |
| 339 | { |
| 340 | point->Z_is_one = 0; |
| 341 | BN_zero(&point->Z); |
| 342 | return 1; |
| 343 | } |
| 344 | |
| 345 | |
| 346 | /* Set the coordinates of an EC_POINT using affine coordinates. |
| 347 | * Note that the simple implementation only uses affine coordinates. |
| 348 | */ |
| 349 | int ec_GF2m_simple_point_set_affine_coordinates(const EC_GROUP *group, EC_POINT *point, |
| 350 | const BIGNUM *x, const BIGNUM *y, BN_CTX *ctx) |
| 351 | { |
| 352 | int ret = 0; |
| 353 | if (x == NULL || y == NULL) |
| 354 | { |
| 355 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT_SET_AFFINE_COORDINATES, ERR_R_PASSED_NULL_PARAMETER); |
| 356 | return 0; |
| 357 | } |
| 358 | |
| 359 | if (!BN_copy(&point->X, x)) goto err; |
| 360 | BN_set_negative(&point->X, 0); |
| 361 | if (!BN_copy(&point->Y, y)) goto err; |
| 362 | BN_set_negative(&point->Y, 0); |
| 363 | if (!BN_copy(&point->Z, BN_value_one())) goto err; |
| 364 | BN_set_negative(&point->Z, 0); |
| 365 | point->Z_is_one = 1; |
| 366 | ret = 1; |
| 367 | |
| 368 | err: |
| 369 | return ret; |
| 370 | } |
| 371 | |
| 372 | |
| 373 | /* Gets the affine coordinates of an EC_POINT. |
| 374 | * Note that the simple implementation only uses affine coordinates. |
| 375 | */ |
| 376 | int ec_GF2m_simple_point_get_affine_coordinates(const EC_GROUP *group, const EC_POINT *point, |
| 377 | BIGNUM *x, BIGNUM *y, BN_CTX *ctx) |
| 378 | { |
| 379 | int ret = 0; |
| 380 | |
| 381 | if (EC_POINT_is_at_infinity(group, point)) |
| 382 | { |
| 383 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT_GET_AFFINE_COORDINATES, EC_R_POINT_AT_INFINITY); |
| 384 | return 0; |
| 385 | } |
| 386 | |
| 387 | if (BN_cmp(&point->Z, BN_value_one())) |
| 388 | { |
| 389 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT_GET_AFFINE_COORDINATES, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); |
| 390 | return 0; |
| 391 | } |
| 392 | if (x != NULL) |
| 393 | { |
| 394 | if (!BN_copy(x, &point->X)) goto err; |
| 395 | BN_set_negative(x, 0); |
| 396 | } |
| 397 | if (y != NULL) |
| 398 | { |
| 399 | if (!BN_copy(y, &point->Y)) goto err; |
| 400 | BN_set_negative(y, 0); |
| 401 | } |
| 402 | ret = 1; |
| 403 | |
| 404 | err: |
| 405 | return ret; |
| 406 | } |
| 407 | |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 408 | |
| 409 | /* Calculates and sets the affine coordinates of an EC_POINT from the given |
| 410 | * compressed coordinates. Uses algorithm 2.3.4 of SEC 1. |
| 411 | * Note that the simple implementation only uses affine coordinates. |
| 412 | * |
| 413 | * The method is from the following publication: |
| 414 | * |
| 415 | * Harper, Menezes, Vanstone: |
| 416 | * "Public-Key Cryptosystems with Very Small Key Lengths", |
| 417 | * EUROCRYPT '92, Springer-Verlag LNCS 658, |
| 418 | * published February 1993 |
| 419 | * |
| 420 | * US Patents 6,141,420 and 6,618,483 (Vanstone, Mullin, Agnew) describe |
| 421 | * the same method, but claim no priority date earlier than July 29, 1994 |
| 422 | * (and additionally fail to cite the EUROCRYPT '92 publication as prior art). |
| 423 | */ |
| 424 | int ec_GF2m_simple_set_compressed_coordinates(const EC_GROUP *group, EC_POINT *point, |
| 425 | const BIGNUM *x_, int y_bit, BN_CTX *ctx) |
| 426 | { |
| 427 | BN_CTX *new_ctx = NULL; |
| 428 | BIGNUM *tmp, *x, *y, *z; |
| 429 | int ret = 0, z0; |
| 430 | |
| 431 | /* clear error queue */ |
| 432 | ERR_clear_error(); |
| 433 | |
| 434 | if (ctx == NULL) |
| 435 | { |
| 436 | ctx = new_ctx = BN_CTX_new(); |
| 437 | if (ctx == NULL) |
| 438 | return 0; |
| 439 | } |
| 440 | |
| 441 | y_bit = (y_bit != 0) ? 1 : 0; |
| 442 | |
| 443 | BN_CTX_start(ctx); |
| 444 | tmp = BN_CTX_get(ctx); |
| 445 | x = BN_CTX_get(ctx); |
| 446 | y = BN_CTX_get(ctx); |
| 447 | z = BN_CTX_get(ctx); |
| 448 | if (z == NULL) goto err; |
| 449 | |
| 450 | if (!BN_GF2m_mod_arr(x, x_, group->poly)) goto err; |
| 451 | if (BN_is_zero(x)) |
| 452 | { |
| 453 | if (!BN_GF2m_mod_sqrt_arr(y, &group->b, group->poly, ctx)) goto err; |
| 454 | } |
| 455 | else |
| 456 | { |
| 457 | if (!group->meth->field_sqr(group, tmp, x, ctx)) goto err; |
| 458 | if (!group->meth->field_div(group, tmp, &group->b, tmp, ctx)) goto err; |
| 459 | if (!BN_GF2m_add(tmp, &group->a, tmp)) goto err; |
| 460 | if (!BN_GF2m_add(tmp, x, tmp)) goto err; |
| 461 | if (!BN_GF2m_mod_solve_quad_arr(z, tmp, group->poly, ctx)) |
| 462 | { |
| 463 | unsigned long err = ERR_peek_last_error(); |
| 464 | |
| 465 | if (ERR_GET_LIB(err) == ERR_LIB_BN && ERR_GET_REASON(err) == BN_R_NO_SOLUTION) |
| 466 | { |
| 467 | ERR_clear_error(); |
| 468 | ECerr(EC_F_EC_GF2M_SIMPLE_SET_COMPRESSED_COORDINATES, EC_R_INVALID_COMPRESSED_POINT); |
| 469 | } |
| 470 | else |
| 471 | ECerr(EC_F_EC_GF2M_SIMPLE_SET_COMPRESSED_COORDINATES, ERR_R_BN_LIB); |
| 472 | goto err; |
| 473 | } |
| 474 | z0 = (BN_is_odd(z)) ? 1 : 0; |
| 475 | if (!group->meth->field_mul(group, y, x, z, ctx)) goto err; |
| 476 | if (z0 != y_bit) |
| 477 | { |
| 478 | if (!BN_GF2m_add(y, y, x)) goto err; |
| 479 | } |
| 480 | } |
| 481 | |
| 482 | if (!EC_POINT_set_affine_coordinates_GF2m(group, point, x, y, ctx)) goto err; |
| 483 | |
| 484 | ret = 1; |
| 485 | |
| 486 | err: |
| 487 | BN_CTX_end(ctx); |
| 488 | if (new_ctx != NULL) |
| 489 | BN_CTX_free(new_ctx); |
| 490 | return ret; |
| 491 | } |
| 492 | |
| 493 | |
| 494 | /* Converts an EC_POINT to an octet string. |
| 495 | * If buf is NULL, the encoded length will be returned. |
| 496 | * If the length len of buf is smaller than required an error will be returned. |
| 497 | */ |
| 498 | size_t ec_GF2m_simple_point2oct(const EC_GROUP *group, const EC_POINT *point, point_conversion_form_t form, |
| 499 | unsigned char *buf, size_t len, BN_CTX *ctx) |
| 500 | { |
| 501 | size_t ret; |
| 502 | BN_CTX *new_ctx = NULL; |
| 503 | int used_ctx = 0; |
| 504 | BIGNUM *x, *y, *yxi; |
| 505 | size_t field_len, i, skip; |
| 506 | |
| 507 | if ((form != POINT_CONVERSION_COMPRESSED) |
| 508 | && (form != POINT_CONVERSION_UNCOMPRESSED) |
| 509 | && (form != POINT_CONVERSION_HYBRID)) |
| 510 | { |
| 511 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, EC_R_INVALID_FORM); |
| 512 | goto err; |
| 513 | } |
| 514 | |
| 515 | if (EC_POINT_is_at_infinity(group, point)) |
| 516 | { |
| 517 | /* encodes to a single 0 octet */ |
| 518 | if (buf != NULL) |
| 519 | { |
| 520 | if (len < 1) |
| 521 | { |
| 522 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL); |
| 523 | return 0; |
| 524 | } |
| 525 | buf[0] = 0; |
| 526 | } |
| 527 | return 1; |
| 528 | } |
| 529 | |
| 530 | |
| 531 | /* ret := required output buffer length */ |
| 532 | field_len = (EC_GROUP_get_degree(group) + 7) / 8; |
| 533 | ret = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2*field_len; |
| 534 | |
| 535 | /* if 'buf' is NULL, just return required length */ |
| 536 | if (buf != NULL) |
| 537 | { |
| 538 | if (len < ret) |
| 539 | { |
| 540 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL); |
| 541 | goto err; |
| 542 | } |
| 543 | |
| 544 | if (ctx == NULL) |
| 545 | { |
| 546 | ctx = new_ctx = BN_CTX_new(); |
| 547 | if (ctx == NULL) |
| 548 | return 0; |
| 549 | } |
| 550 | |
| 551 | BN_CTX_start(ctx); |
| 552 | used_ctx = 1; |
| 553 | x = BN_CTX_get(ctx); |
| 554 | y = BN_CTX_get(ctx); |
| 555 | yxi = BN_CTX_get(ctx); |
| 556 | if (yxi == NULL) goto err; |
| 557 | |
| 558 | if (!EC_POINT_get_affine_coordinates_GF2m(group, point, x, y, ctx)) goto err; |
| 559 | |
| 560 | buf[0] = form; |
| 561 | if ((form != POINT_CONVERSION_UNCOMPRESSED) && !BN_is_zero(x)) |
| 562 | { |
| 563 | if (!group->meth->field_div(group, yxi, y, x, ctx)) goto err; |
| 564 | if (BN_is_odd(yxi)) buf[0]++; |
| 565 | } |
| 566 | |
| 567 | i = 1; |
| 568 | |
| 569 | skip = field_len - BN_num_bytes(x); |
| 570 | if (skip > field_len) |
| 571 | { |
| 572 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); |
| 573 | goto err; |
| 574 | } |
| 575 | while (skip > 0) |
| 576 | { |
| 577 | buf[i++] = 0; |
| 578 | skip--; |
| 579 | } |
| 580 | skip = BN_bn2bin(x, buf + i); |
| 581 | i += skip; |
| 582 | if (i != 1 + field_len) |
| 583 | { |
| 584 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); |
| 585 | goto err; |
| 586 | } |
| 587 | |
| 588 | if (form == POINT_CONVERSION_UNCOMPRESSED || form == POINT_CONVERSION_HYBRID) |
| 589 | { |
| 590 | skip = field_len - BN_num_bytes(y); |
| 591 | if (skip > field_len) |
| 592 | { |
| 593 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); |
| 594 | goto err; |
| 595 | } |
| 596 | while (skip > 0) |
| 597 | { |
| 598 | buf[i++] = 0; |
| 599 | skip--; |
| 600 | } |
| 601 | skip = BN_bn2bin(y, buf + i); |
| 602 | i += skip; |
| 603 | } |
| 604 | |
| 605 | if (i != ret) |
| 606 | { |
| 607 | ECerr(EC_F_EC_GF2M_SIMPLE_POINT2OCT, ERR_R_INTERNAL_ERROR); |
| 608 | goto err; |
| 609 | } |
| 610 | } |
| 611 | |
| 612 | if (used_ctx) |
| 613 | BN_CTX_end(ctx); |
| 614 | if (new_ctx != NULL) |
| 615 | BN_CTX_free(new_ctx); |
| 616 | return ret; |
| 617 | |
| 618 | err: |
| 619 | if (used_ctx) |
| 620 | BN_CTX_end(ctx); |
| 621 | if (new_ctx != NULL) |
| 622 | BN_CTX_free(new_ctx); |
| 623 | return 0; |
| 624 | } |
| 625 | |
| 626 | |
| 627 | /* Converts an octet string representation to an EC_POINT. |
| 628 | * Note that the simple implementation only uses affine coordinates. |
| 629 | */ |
| 630 | int ec_GF2m_simple_oct2point(const EC_GROUP *group, EC_POINT *point, |
| 631 | const unsigned char *buf, size_t len, BN_CTX *ctx) |
| 632 | { |
| 633 | point_conversion_form_t form; |
| 634 | int y_bit; |
| 635 | BN_CTX *new_ctx = NULL; |
| 636 | BIGNUM *x, *y, *yxi; |
| 637 | size_t field_len, enc_len; |
| 638 | int ret = 0; |
| 639 | |
| 640 | if (len == 0) |
| 641 | { |
| 642 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_BUFFER_TOO_SMALL); |
| 643 | return 0; |
| 644 | } |
| 645 | form = buf[0]; |
| 646 | y_bit = form & 1; |
| 647 | form = form & ~1U; |
| 648 | if ((form != 0) && (form != POINT_CONVERSION_COMPRESSED) |
| 649 | && (form != POINT_CONVERSION_UNCOMPRESSED) |
| 650 | && (form != POINT_CONVERSION_HYBRID)) |
| 651 | { |
| 652 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 653 | return 0; |
| 654 | } |
| 655 | if ((form == 0 || form == POINT_CONVERSION_UNCOMPRESSED) && y_bit) |
| 656 | { |
| 657 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 658 | return 0; |
| 659 | } |
| 660 | |
| 661 | if (form == 0) |
| 662 | { |
| 663 | if (len != 1) |
| 664 | { |
| 665 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 666 | return 0; |
| 667 | } |
| 668 | |
| 669 | return EC_POINT_set_to_infinity(group, point); |
| 670 | } |
| 671 | |
| 672 | field_len = (EC_GROUP_get_degree(group) + 7) / 8; |
| 673 | enc_len = (form == POINT_CONVERSION_COMPRESSED) ? 1 + field_len : 1 + 2*field_len; |
| 674 | |
| 675 | if (len != enc_len) |
| 676 | { |
| 677 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 678 | return 0; |
| 679 | } |
| 680 | |
| 681 | if (ctx == NULL) |
| 682 | { |
| 683 | ctx = new_ctx = BN_CTX_new(); |
| 684 | if (ctx == NULL) |
| 685 | return 0; |
| 686 | } |
| 687 | |
| 688 | BN_CTX_start(ctx); |
| 689 | x = BN_CTX_get(ctx); |
| 690 | y = BN_CTX_get(ctx); |
| 691 | yxi = BN_CTX_get(ctx); |
| 692 | if (yxi == NULL) goto err; |
| 693 | |
| 694 | if (!BN_bin2bn(buf + 1, field_len, x)) goto err; |
| 695 | if (BN_ucmp(x, &group->field) >= 0) |
| 696 | { |
| 697 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 698 | goto err; |
| 699 | } |
| 700 | |
| 701 | if (form == POINT_CONVERSION_COMPRESSED) |
| 702 | { |
| 703 | if (!EC_POINT_set_compressed_coordinates_GF2m(group, point, x, y_bit, ctx)) goto err; |
| 704 | } |
| 705 | else |
| 706 | { |
| 707 | if (!BN_bin2bn(buf + 1 + field_len, field_len, y)) goto err; |
| 708 | if (BN_ucmp(y, &group->field) >= 0) |
| 709 | { |
| 710 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 711 | goto err; |
| 712 | } |
| 713 | if (form == POINT_CONVERSION_HYBRID) |
| 714 | { |
| 715 | if (!group->meth->field_div(group, yxi, y, x, ctx)) goto err; |
| 716 | if (y_bit != BN_is_odd(yxi)) |
| 717 | { |
| 718 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_INVALID_ENCODING); |
| 719 | goto err; |
| 720 | } |
| 721 | } |
| 722 | |
| 723 | if (!EC_POINT_set_affine_coordinates_GF2m(group, point, x, y, ctx)) goto err; |
| 724 | } |
| 725 | |
| 726 | if (!EC_POINT_is_on_curve(group, point, ctx)) /* test required by X9.62 */ |
| 727 | { |
| 728 | ECerr(EC_F_EC_GF2M_SIMPLE_OCT2POINT, EC_R_POINT_IS_NOT_ON_CURVE); |
| 729 | goto err; |
| 730 | } |
| 731 | |
| 732 | ret = 1; |
| 733 | |
| 734 | err: |
| 735 | BN_CTX_end(ctx); |
| 736 | if (new_ctx != NULL) |
| 737 | BN_CTX_free(new_ctx); |
| 738 | return ret; |
| 739 | } |
| 740 | |
| 741 | |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 742 | /* Computes a + b and stores the result in r. r could be a or b, a could be b. |
| 743 | * Uses algorithm A.10.2 of IEEE P1363. |
| 744 | */ |
| 745 | int ec_GF2m_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, const EC_POINT *b, BN_CTX *ctx) |
| 746 | { |
| 747 | BN_CTX *new_ctx = NULL; |
| 748 | BIGNUM *x0, *y0, *x1, *y1, *x2, *y2, *s, *t; |
| 749 | int ret = 0; |
| 750 | |
| 751 | if (EC_POINT_is_at_infinity(group, a)) |
| 752 | { |
| 753 | if (!EC_POINT_copy(r, b)) return 0; |
| 754 | return 1; |
| 755 | } |
| 756 | |
| 757 | if (EC_POINT_is_at_infinity(group, b)) |
| 758 | { |
| 759 | if (!EC_POINT_copy(r, a)) return 0; |
| 760 | return 1; |
| 761 | } |
| 762 | |
| 763 | if (ctx == NULL) |
| 764 | { |
| 765 | ctx = new_ctx = BN_CTX_new(); |
| 766 | if (ctx == NULL) |
| 767 | return 0; |
| 768 | } |
| 769 | |
| 770 | BN_CTX_start(ctx); |
| 771 | x0 = BN_CTX_get(ctx); |
| 772 | y0 = BN_CTX_get(ctx); |
| 773 | x1 = BN_CTX_get(ctx); |
| 774 | y1 = BN_CTX_get(ctx); |
| 775 | x2 = BN_CTX_get(ctx); |
| 776 | y2 = BN_CTX_get(ctx); |
| 777 | s = BN_CTX_get(ctx); |
| 778 | t = BN_CTX_get(ctx); |
| 779 | if (t == NULL) goto err; |
| 780 | |
| 781 | if (a->Z_is_one) |
| 782 | { |
| 783 | if (!BN_copy(x0, &a->X)) goto err; |
| 784 | if (!BN_copy(y0, &a->Y)) goto err; |
| 785 | } |
| 786 | else |
| 787 | { |
| 788 | if (!EC_POINT_get_affine_coordinates_GF2m(group, a, x0, y0, ctx)) goto err; |
| 789 | } |
| 790 | if (b->Z_is_one) |
| 791 | { |
| 792 | if (!BN_copy(x1, &b->X)) goto err; |
| 793 | if (!BN_copy(y1, &b->Y)) goto err; |
| 794 | } |
| 795 | else |
| 796 | { |
| 797 | if (!EC_POINT_get_affine_coordinates_GF2m(group, b, x1, y1, ctx)) goto err; |
| 798 | } |
| 799 | |
| 800 | |
| 801 | if (BN_GF2m_cmp(x0, x1)) |
| 802 | { |
| 803 | if (!BN_GF2m_add(t, x0, x1)) goto err; |
| 804 | if (!BN_GF2m_add(s, y0, y1)) goto err; |
| 805 | if (!group->meth->field_div(group, s, s, t, ctx)) goto err; |
| 806 | if (!group->meth->field_sqr(group, x2, s, ctx)) goto err; |
| 807 | if (!BN_GF2m_add(x2, x2, &group->a)) goto err; |
| 808 | if (!BN_GF2m_add(x2, x2, s)) goto err; |
| 809 | if (!BN_GF2m_add(x2, x2, t)) goto err; |
| 810 | } |
| 811 | else |
| 812 | { |
| 813 | if (BN_GF2m_cmp(y0, y1) || BN_is_zero(x1)) |
| 814 | { |
| 815 | if (!EC_POINT_set_to_infinity(group, r)) goto err; |
| 816 | ret = 1; |
| 817 | goto err; |
| 818 | } |
| 819 | if (!group->meth->field_div(group, s, y1, x1, ctx)) goto err; |
| 820 | if (!BN_GF2m_add(s, s, x1)) goto err; |
| 821 | |
| 822 | if (!group->meth->field_sqr(group, x2, s, ctx)) goto err; |
| 823 | if (!BN_GF2m_add(x2, x2, s)) goto err; |
| 824 | if (!BN_GF2m_add(x2, x2, &group->a)) goto err; |
| 825 | } |
| 826 | |
| 827 | if (!BN_GF2m_add(y2, x1, x2)) goto err; |
| 828 | if (!group->meth->field_mul(group, y2, y2, s, ctx)) goto err; |
| 829 | if (!BN_GF2m_add(y2, y2, x2)) goto err; |
| 830 | if (!BN_GF2m_add(y2, y2, y1)) goto err; |
| 831 | |
| 832 | if (!EC_POINT_set_affine_coordinates_GF2m(group, r, x2, y2, ctx)) goto err; |
| 833 | |
| 834 | ret = 1; |
| 835 | |
| 836 | err: |
| 837 | BN_CTX_end(ctx); |
| 838 | if (new_ctx != NULL) |
| 839 | BN_CTX_free(new_ctx); |
| 840 | return ret; |
| 841 | } |
| 842 | |
| 843 | |
| 844 | /* Computes 2 * a and stores the result in r. r could be a. |
| 845 | * Uses algorithm A.10.2 of IEEE P1363. |
| 846 | */ |
| 847 | int ec_GF2m_simple_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, BN_CTX *ctx) |
| 848 | { |
| 849 | return ec_GF2m_simple_add(group, r, a, a, ctx); |
| 850 | } |
| 851 | |
| 852 | |
| 853 | int ec_GF2m_simple_invert(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx) |
| 854 | { |
| 855 | if (EC_POINT_is_at_infinity(group, point) || BN_is_zero(&point->Y)) |
| 856 | /* point is its own inverse */ |
| 857 | return 1; |
| 858 | |
| 859 | if (!EC_POINT_make_affine(group, point, ctx)) return 0; |
| 860 | return BN_GF2m_add(&point->Y, &point->X, &point->Y); |
| 861 | } |
| 862 | |
| 863 | |
| 864 | /* Indicates whether the given point is the point at infinity. */ |
| 865 | int ec_GF2m_simple_is_at_infinity(const EC_GROUP *group, const EC_POINT *point) |
| 866 | { |
| 867 | return BN_is_zero(&point->Z); |
| 868 | } |
| 869 | |
| 870 | |
| 871 | /* Determines whether the given EC_POINT is an actual point on the curve defined |
| 872 | * in the EC_GROUP. A point is valid if it satisfies the Weierstrass equation: |
| 873 | * y^2 + x*y = x^3 + a*x^2 + b. |
| 874 | */ |
| 875 | int ec_GF2m_simple_is_on_curve(const EC_GROUP *group, const EC_POINT *point, BN_CTX *ctx) |
| 876 | { |
| 877 | int ret = -1; |
| 878 | BN_CTX *new_ctx = NULL; |
| 879 | BIGNUM *lh, *y2; |
| 880 | int (*field_mul)(const EC_GROUP *, BIGNUM *, const BIGNUM *, const BIGNUM *, BN_CTX *); |
| 881 | int (*field_sqr)(const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *); |
| 882 | |
| 883 | if (EC_POINT_is_at_infinity(group, point)) |
| 884 | return 1; |
| 885 | |
| 886 | field_mul = group->meth->field_mul; |
| 887 | field_sqr = group->meth->field_sqr; |
| 888 | |
| 889 | /* only support affine coordinates */ |
Alexandre Savard | 7541067 | 2012-08-08 09:50:01 -0400 | [diff] [blame] | 890 | if (!point->Z_is_one) goto err; |
Alexandre Savard | 1b09e31 | 2012-08-07 20:33:29 -0400 | [diff] [blame] | 891 | |
| 892 | if (ctx == NULL) |
| 893 | { |
| 894 | ctx = new_ctx = BN_CTX_new(); |
| 895 | if (ctx == NULL) |
| 896 | return -1; |
| 897 | } |
| 898 | |
| 899 | BN_CTX_start(ctx); |
| 900 | y2 = BN_CTX_get(ctx); |
| 901 | lh = BN_CTX_get(ctx); |
| 902 | if (lh == NULL) goto err; |
| 903 | |
| 904 | /* We have a curve defined by a Weierstrass equation |
| 905 | * y^2 + x*y = x^3 + a*x^2 + b. |
| 906 | * <=> x^3 + a*x^2 + x*y + b + y^2 = 0 |
| 907 | * <=> ((x + a) * x + y ) * x + b + y^2 = 0 |
| 908 | */ |
| 909 | if (!BN_GF2m_add(lh, &point->X, &group->a)) goto err; |
| 910 | if (!field_mul(group, lh, lh, &point->X, ctx)) goto err; |
| 911 | if (!BN_GF2m_add(lh, lh, &point->Y)) goto err; |
| 912 | if (!field_mul(group, lh, lh, &point->X, ctx)) goto err; |
| 913 | if (!BN_GF2m_add(lh, lh, &group->b)) goto err; |
| 914 | if (!field_sqr(group, y2, &point->Y, ctx)) goto err; |
| 915 | if (!BN_GF2m_add(lh, lh, y2)) goto err; |
| 916 | ret = BN_is_zero(lh); |
| 917 | err: |
| 918 | if (ctx) BN_CTX_end(ctx); |
| 919 | if (new_ctx) BN_CTX_free(new_ctx); |
| 920 | return ret; |
| 921 | } |
| 922 | |
| 923 | |
| 924 | /* Indicates whether two points are equal. |
| 925 | * Return values: |
| 926 | * -1 error |
| 927 | * 0 equal (in affine coordinates) |
| 928 | * 1 not equal |
| 929 | */ |
| 930 | int ec_GF2m_simple_cmp(const EC_GROUP *group, const EC_POINT *a, const EC_POINT *b, BN_CTX *ctx) |
| 931 | { |
| 932 | BIGNUM *aX, *aY, *bX, *bY; |
| 933 | BN_CTX *new_ctx = NULL; |
| 934 | int ret = -1; |
| 935 | |
| 936 | if (EC_POINT_is_at_infinity(group, a)) |
| 937 | { |
| 938 | return EC_POINT_is_at_infinity(group, b) ? 0 : 1; |
| 939 | } |
| 940 | |
| 941 | if (EC_POINT_is_at_infinity(group, b)) |
| 942 | return 1; |
| 943 | |
| 944 | if (a->Z_is_one && b->Z_is_one) |
| 945 | { |
| 946 | return ((BN_cmp(&a->X, &b->X) == 0) && BN_cmp(&a->Y, &b->Y) == 0) ? 0 : 1; |
| 947 | } |
| 948 | |
| 949 | if (ctx == NULL) |
| 950 | { |
| 951 | ctx = new_ctx = BN_CTX_new(); |
| 952 | if (ctx == NULL) |
| 953 | return -1; |
| 954 | } |
| 955 | |
| 956 | BN_CTX_start(ctx); |
| 957 | aX = BN_CTX_get(ctx); |
| 958 | aY = BN_CTX_get(ctx); |
| 959 | bX = BN_CTX_get(ctx); |
| 960 | bY = BN_CTX_get(ctx); |
| 961 | if (bY == NULL) goto err; |
| 962 | |
| 963 | if (!EC_POINT_get_affine_coordinates_GF2m(group, a, aX, aY, ctx)) goto err; |
| 964 | if (!EC_POINT_get_affine_coordinates_GF2m(group, b, bX, bY, ctx)) goto err; |
| 965 | ret = ((BN_cmp(aX, bX) == 0) && BN_cmp(aY, bY) == 0) ? 0 : 1; |
| 966 | |
| 967 | err: |
| 968 | if (ctx) BN_CTX_end(ctx); |
| 969 | if (new_ctx) BN_CTX_free(new_ctx); |
| 970 | return ret; |
| 971 | } |
| 972 | |
| 973 | |
| 974 | /* Forces the given EC_POINT to internally use affine coordinates. */ |
| 975 | int ec_GF2m_simple_make_affine(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx) |
| 976 | { |
| 977 | BN_CTX *new_ctx = NULL; |
| 978 | BIGNUM *x, *y; |
| 979 | int ret = 0; |
| 980 | |
| 981 | if (point->Z_is_one || EC_POINT_is_at_infinity(group, point)) |
| 982 | return 1; |
| 983 | |
| 984 | if (ctx == NULL) |
| 985 | { |
| 986 | ctx = new_ctx = BN_CTX_new(); |
| 987 | if (ctx == NULL) |
| 988 | return 0; |
| 989 | } |
| 990 | |
| 991 | BN_CTX_start(ctx); |
| 992 | x = BN_CTX_get(ctx); |
| 993 | y = BN_CTX_get(ctx); |
| 994 | if (y == NULL) goto err; |
| 995 | |
| 996 | if (!EC_POINT_get_affine_coordinates_GF2m(group, point, x, y, ctx)) goto err; |
| 997 | if (!BN_copy(&point->X, x)) goto err; |
| 998 | if (!BN_copy(&point->Y, y)) goto err; |
| 999 | if (!BN_one(&point->Z)) goto err; |
| 1000 | |
| 1001 | ret = 1; |
| 1002 | |
| 1003 | err: |
| 1004 | if (ctx) BN_CTX_end(ctx); |
| 1005 | if (new_ctx) BN_CTX_free(new_ctx); |
| 1006 | return ret; |
| 1007 | } |
| 1008 | |
| 1009 | |
| 1010 | /* Forces each of the EC_POINTs in the given array to use affine coordinates. */ |
| 1011 | int ec_GF2m_simple_points_make_affine(const EC_GROUP *group, size_t num, EC_POINT *points[], BN_CTX *ctx) |
| 1012 | { |
| 1013 | size_t i; |
| 1014 | |
| 1015 | for (i = 0; i < num; i++) |
| 1016 | { |
| 1017 | if (!group->meth->make_affine(group, points[i], ctx)) return 0; |
| 1018 | } |
| 1019 | |
| 1020 | return 1; |
| 1021 | } |
| 1022 | |
| 1023 | |
| 1024 | /* Wrapper to simple binary polynomial field multiplication implementation. */ |
| 1025 | int ec_GF2m_simple_field_mul(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx) |
| 1026 | { |
| 1027 | return BN_GF2m_mod_mul_arr(r, a, b, group->poly, ctx); |
| 1028 | } |
| 1029 | |
| 1030 | |
| 1031 | /* Wrapper to simple binary polynomial field squaring implementation. */ |
| 1032 | int ec_GF2m_simple_field_sqr(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, BN_CTX *ctx) |
| 1033 | { |
| 1034 | return BN_GF2m_mod_sqr_arr(r, a, group->poly, ctx); |
| 1035 | } |
| 1036 | |
| 1037 | |
| 1038 | /* Wrapper to simple binary polynomial field division implementation. */ |
| 1039 | int ec_GF2m_simple_field_div(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx) |
| 1040 | { |
| 1041 | return BN_GF2m_mod_div(r, a, b, &group->field, ctx); |
| 1042 | } |