1 /* Originally written by Bodo Moeller 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 #ifndef OPENSSL_HEADER_EC_H 69 #define OPENSSL_HEADER_EC_H 70 71 #include <openssl/base.h> 72 73 #if defined(__cplusplus) 74 extern "C" { 75 #endif 76 77 78 /* Low-level operations on elliptic curves. */ 79 80 81 typedef struct ec_group_st EC_GROUP; 82 typedef struct ec_point_st EC_POINT; 83 84 /** Enum for the point conversion form as defined in X9.62 (ECDSA) 85 * for the encoding of a elliptic curve point (x,y) */ 86 typedef enum { 87 /** the point is encoded as z||x, where the octet z specifies 88 * which solution of the quadratic equation y is */ 89 POINT_CONVERSION_COMPRESSED = 2, 90 /** the point is encoded as z||x||y, where z is the octet 0x04 */ 91 POINT_CONVERSION_UNCOMPRESSED = 4 92 } point_conversion_form_t; 93 94 95 /* Elliptic curve groups. */ 96 97 /* EC_GROUP_new_by_curve_name returns a fresh EC_GROUP object for the elliptic 98 * curve specified by |nid|, or NULL on error. 99 * 100 * The supported NIDs are: 101 * NID_secp224r1, 102 * NID_X9_62_prime256v1, 103 * NID_secp384r1, 104 * NID_secp521r1 */ 105 OPENSSL_EXPORT EC_GROUP *EC_GROUP_new_by_curve_name(int nid); 106 107 /* EC_GROUP_free frees |group| and the data that it points to. */ 108 OPENSSL_EXPORT void EC_GROUP_free(EC_GROUP *group); 109 110 /* EC_GROUP_dup returns a fresh |EC_GROUP| which is equal to |a| or NULL on 111 * error. */ 112 OPENSSL_EXPORT EC_GROUP *EC_GROUP_dup(const EC_GROUP *a); 113 114 /* EC_GROUP_cmp returns zero if |a| and |b| are the same group and non-zero 115 * otherwise. */ 116 OPENSSL_EXPORT int EC_GROUP_cmp(const EC_GROUP *a, const EC_GROUP *b, 117 BN_CTX *ignored); 118 119 /* EC_GROUP_get0_generator returns a pointer to the internal |EC_POINT| object 120 * in |group| that specifies the generator for the group. */ 121 OPENSSL_EXPORT const EC_POINT *EC_GROUP_get0_generator(const EC_GROUP *group); 122 123 /* EC_GROUP_get0_order returns a pointer to the internal |BIGNUM| object in 124 * |group| that specifies the order of the group. */ 125 OPENSSL_EXPORT const BIGNUM *EC_GROUP_get0_order(const EC_GROUP *group); 126 127 /* EC_GROUP_get_cofactor sets |*cofactor| to the cofactor of |group| using 128 * |ctx|, if it's not NULL. It returns one on success and zero otherwise. */ 129 OPENSSL_EXPORT int EC_GROUP_get_cofactor(const EC_GROUP *group, 130 BIGNUM *cofactor, BN_CTX *ctx); 131 132 /* EC_GROUP_get_curve_GFp gets various parameters about a group. It sets 133 * |*out_p| to the order of the coordinate field and |*out_a| and |*out_b| to 134 * the parameters of the curve when expressed as y² = x³ + ax + b. Any of the 135 * output parameters can be NULL. It returns one on success and zero on 136 * error. */ 137 OPENSSL_EXPORT int EC_GROUP_get_curve_GFp(const EC_GROUP *group, BIGNUM *out_p, 138 BIGNUM *out_a, BIGNUM *out_b, 139 BN_CTX *ctx); 140 141 /* EC_GROUP_get_curve_name returns a NID that identifies |group|. */ 142 OPENSSL_EXPORT int EC_GROUP_get_curve_name(const EC_GROUP *group); 143 144 /* EC_GROUP_get_degree returns the number of bits needed to represent an 145 * element of the field underlying |group|. */ 146 OPENSSL_EXPORT unsigned EC_GROUP_get_degree(const EC_GROUP *group); 147 148 149 /* Points on elliptic curves. */ 150 151 /* EC_POINT_new returns a fresh |EC_POINT| object in the given group, or NULL 152 * on error. */ 153 OPENSSL_EXPORT EC_POINT *EC_POINT_new(const EC_GROUP *group); 154 155 /* EC_POINT_free frees |point| and the data that it points to. */ 156 OPENSSL_EXPORT void EC_POINT_free(EC_POINT *point); 157 158 /* EC_POINT_clear_free clears the data that |point| points to, frees it and 159 * then frees |point| itself. */ 160 OPENSSL_EXPORT void EC_POINT_clear_free(EC_POINT *point); 161 162 /* EC_POINT_copy sets |*dest| equal to |*src|. It returns one on success and 163 * zero otherwise. */ 164 OPENSSL_EXPORT int EC_POINT_copy(EC_POINT *dest, const EC_POINT *src); 165 166 /* EC_POINT_dup returns a fresh |EC_POINT| that contains the same values as 167 * |src|, or NULL on error. */ 168 OPENSSL_EXPORT EC_POINT *EC_POINT_dup(const EC_POINT *src, 169 const EC_GROUP *group); 170 171 /* EC_POINT_set_to_infinity sets |point| to be the "point at infinity" for the 172 * given group. */ 173 OPENSSL_EXPORT int EC_POINT_set_to_infinity(const EC_GROUP *group, 174 EC_POINT *point); 175 176 /* EC_POINT_is_at_infinity returns one iff |point| is the point at infinity and 177 * zero otherwise. */ 178 OPENSSL_EXPORT int EC_POINT_is_at_infinity(const EC_GROUP *group, 179 const EC_POINT *point); 180 181 /* EC_POINT_is_on_curve returns one if |point| is an element of |group| and 182 * zero otheriwse. If |ctx| is non-NULL, it may be used. */ 183 OPENSSL_EXPORT int EC_POINT_is_on_curve(const EC_GROUP *group, 184 const EC_POINT *point, BN_CTX *ctx); 185 186 /* EC_POINT_cmp returns zero if |a| is equal to |b|, greater than zero is 187 * non-equal and -1 on error. If |ctx| is not NULL, it may be used. */ 188 OPENSSL_EXPORT int EC_POINT_cmp(const EC_GROUP *group, const EC_POINT *a, 189 const EC_POINT *b, BN_CTX *ctx); 190 191 /* EC_POINT_make_affine converts |point| to affine form, internally. It returns 192 * one on success and zero otherwise. If |ctx| is not NULL, it may be used. */ 193 OPENSSL_EXPORT int EC_POINT_make_affine(const EC_GROUP *group, EC_POINT *point, 194 BN_CTX *ctx); 195 196 /* EC_POINTs_make_affine converts |num| points from |points| to affine form, 197 * internally. It returns one on success and zero otherwise. If |ctx| is not 198 * NULL, it may be used. */ 199 OPENSSL_EXPORT int EC_POINTs_make_affine(const EC_GROUP *group, size_t num, 200 EC_POINT *points[], BN_CTX *ctx); 201 202 203 /* Point conversion. */ 204 205 /* EC_POINT_get_affine_coordinates_GFp sets |x| and |y| to the affine value of 206 * |point| using |ctx|, if it's not NULL. It returns one on success and zero 207 * otherwise. */ 208 OPENSSL_EXPORT int EC_POINT_get_affine_coordinates_GFp(const EC_GROUP *group, 209 const EC_POINT *point, 210 BIGNUM *x, BIGNUM *y, 211 BN_CTX *ctx); 212 213 /* EC_POINT_set_affine_coordinates_GFp sets the value of |p| to be (|x|, |y|). 214 * The |ctx| argument may be used if not NULL. It returns one on success or 215 * zero on error. Note that, unlike with OpenSSL, it's considered an error if 216 * the point is not on the curve. */ 217 OPENSSL_EXPORT int EC_POINT_set_affine_coordinates_GFp(const EC_GROUP *group, 218 EC_POINT *point, 219 const BIGNUM *x, 220 const BIGNUM *y, 221 BN_CTX *ctx); 222 223 /* EC_POINT_point2oct serialises |point| into the X9.62 form given by |form| 224 * into, at most, |len| bytes at |buf|. It returns the number of bytes written 225 * or zero on error if |buf| is non-NULL, else the number of bytes needed. The 226 * |ctx| argument may be used if not NULL. */ 227 OPENSSL_EXPORT size_t EC_POINT_point2oct(const EC_GROUP *group, 228 const EC_POINT *point, 229 point_conversion_form_t form, 230 uint8_t *buf, size_t len, BN_CTX *ctx); 231 232 /* EC_POINT_oct2point sets |point| from |len| bytes of X9.62 format 233 * serialisation in |buf|. It returns one on success and zero otherwise. The 234 * |ctx| argument may be used if not NULL. */ 235 OPENSSL_EXPORT int EC_POINT_oct2point(const EC_GROUP *group, EC_POINT *point, 236 const uint8_t *buf, size_t len, 237 BN_CTX *ctx); 238 239 /* EC_POINT_set_compressed_coordinates_GFp sets |point| to equal the point with 240 * the given |x| coordinate and the y coordinate specified by |y_bit| (see 241 * X9.62). It returns one on success and zero otherwise. */ 242 OPENSSL_EXPORT int EC_POINT_set_compressed_coordinates_GFp( 243 const EC_GROUP *group, EC_POINT *point, const BIGNUM *x, int y_bit, 244 BN_CTX *ctx); 245 246 247 /* Group operations. */ 248 249 /* EC_POINT_add sets |r| equal to |a| plus |b|. It returns one on success and 250 * zero otherwise. If |ctx| is not NULL, it may be used. */ 251 OPENSSL_EXPORT int EC_POINT_add(const EC_GROUP *group, EC_POINT *r, 252 const EC_POINT *a, const EC_POINT *b, 253 BN_CTX *ctx); 254 255 /* EC_POINT_dbl sets |r| equal to |a| plus |a|. It returns one on success and 256 * zero otherwise. If |ctx| is not NULL, it may be used. */ 257 OPENSSL_EXPORT int EC_POINT_dbl(const EC_GROUP *group, EC_POINT *r, 258 const EC_POINT *a, BN_CTX *ctx); 259 260 /* EC_POINT_invert sets |a| equal to minus |a|. It returns one on success and zero 261 * otherwise. If |ctx| is not NULL, it may be used. */ 262 OPENSSL_EXPORT int EC_POINT_invert(const EC_GROUP *group, EC_POINT *a, 263 BN_CTX *ctx); 264 265 /* EC_POINT_mul sets r = generator*n + q*m. It returns one on success and zero 266 * otherwise. If |ctx| is not NULL, it may be used. */ 267 OPENSSL_EXPORT int EC_POINT_mul(const EC_GROUP *group, EC_POINT *r, 268 const BIGNUM *n, const EC_POINT *q, 269 const BIGNUM *m, BN_CTX *ctx); 270 271 272 /* Deprecated functions. */ 273 274 /* EC_GROUP_new_curve_GFp creates a new, arbitrary elliptic curve group based 275 * on the equation y² = x³ + a·x + b. It returns the new group or NULL on 276 * error. 277 * 278 * |EC_GROUP|s returned by this function will always compare as unequal via 279 * |EC_GROUP_cmp| (even to themselves). |EC_GROUP_get_curve_name| will always 280 * return |NID_undef|. */ 281 OPENSSL_EXPORT EC_GROUP *EC_GROUP_new_curve_GFp(const BIGNUM *p, 282 const BIGNUM *a, 283 const BIGNUM *b, BN_CTX *ctx); 284 285 /* EC_GROUP_get_order sets |*order| to the order of |group|, if it's not 286 * NULL. It returns one on success and zero otherwise. |ctx| is ignored. Use 287 * |EC_GROUP_get0_order| instead. */ 288 OPENSSL_EXPORT int EC_GROUP_get_order(const EC_GROUP *group, BIGNUM *order, 289 BN_CTX *ctx); 290 291 /* EC_GROUP_set_generator sets the generator for |group| to |generator|, which 292 * must have the given order and cofactor. This should only be used with 293 * |EC_GROUP| objects returned by |EC_GROUP_new_curve_GFp|. */ 294 OPENSSL_EXPORT int EC_GROUP_set_generator(EC_GROUP *group, 295 const EC_POINT *generator, 296 const BIGNUM *order, 297 const BIGNUM *cofactor); 298 299 /* EC_GROUP_set_asn1_flag does nothing. */ 300 OPENSSL_EXPORT void EC_GROUP_set_asn1_flag(EC_GROUP *group, int flag); 301 302 #define OPENSSL_EC_NAMED_CURVE 0 303 304 typedef struct ec_method_st EC_METHOD; 305 306 /* EC_GROUP_method_of returns NULL. */ 307 OPENSSL_EXPORT const EC_METHOD *EC_GROUP_method_of(const EC_GROUP *group); 308 309 /* EC_METHOD_get_field_type returns NID_X9_62_prime_field. */ 310 OPENSSL_EXPORT int EC_METHOD_get_field_type(const EC_METHOD *meth); 311 312 /* EC_GROUP_set_point_conversion_form aborts the process if |form| is not 313 * |POINT_CONVERSION_UNCOMPRESSED| and otherwise does nothing. */ 314 OPENSSL_EXPORT void EC_GROUP_set_point_conversion_form( 315 EC_GROUP *group, point_conversion_form_t form); 316 317 318 /* Old code expects to get EC_KEY from ec.h. */ 319 #include <openssl/ec_key.h> 320 321 322 #if defined(__cplusplus) 323 } /* extern C */ 324 #endif 325 326 #define EC_R_BUFFER_TOO_SMALL 100 327 #define EC_R_COORDINATES_OUT_OF_RANGE 101 328 #define EC_R_D2I_ECPKPARAMETERS_FAILURE 102 329 #define EC_R_EC_GROUP_NEW_BY_NAME_FAILURE 103 330 #define EC_R_GROUP2PKPARAMETERS_FAILURE 104 331 #define EC_R_I2D_ECPKPARAMETERS_FAILURE 105 332 #define EC_R_INCOMPATIBLE_OBJECTS 106 333 #define EC_R_INVALID_COMPRESSED_POINT 107 334 #define EC_R_INVALID_COMPRESSION_BIT 108 335 #define EC_R_INVALID_ENCODING 109 336 #define EC_R_INVALID_FIELD 110 337 #define EC_R_INVALID_FORM 111 338 #define EC_R_INVALID_GROUP_ORDER 112 339 #define EC_R_INVALID_PRIVATE_KEY 113 340 #define EC_R_MISSING_PARAMETERS 114 341 #define EC_R_MISSING_PRIVATE_KEY 115 342 #define EC_R_NON_NAMED_CURVE 116 343 #define EC_R_NOT_INITIALIZED 117 344 #define EC_R_PKPARAMETERS2GROUP_FAILURE 118 345 #define EC_R_POINT_AT_INFINITY 119 346 #define EC_R_POINT_IS_NOT_ON_CURVE 120 347 #define EC_R_SLOT_FULL 121 348 #define EC_R_UNDEFINED_GENERATOR 122 349 #define EC_R_UNKNOWN_GROUP 123 350 #define EC_R_UNKNOWN_ORDER 124 351 #define EC_R_WRONG_ORDER 125 352 #define EC_R_BIGNUM_OUT_OF_RANGE 126 353 #define EC_R_WRONG_CURVE_PARAMETERS 127 354 355 #endif /* OPENSSL_HEADER_EC_H */ 356