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_KEY_H 69 #define OPENSSL_HEADER_EC_KEY_H 70 71 #include <openssl/base.h> 72 73 #include <openssl/ec.h> 74 #include <openssl/engine.h> 75 #include <openssl/ex_data.h> 76 77 #if defined(__cplusplus) 78 extern "C" { 79 #endif 80 81 82 // ec_key.h contains functions that handle elliptic-curve points that are 83 // public/private keys. 84 85 86 // EC key objects. 87 // 88 // An |EC_KEY| object represents a public or private EC key. A given object may 89 // be used concurrently on multiple threads by non-mutating functions, provided 90 // no other thread is concurrently calling a mutating function. Unless otherwise 91 // documented, functions which take a |const| pointer are non-mutating and 92 // functions which take a non-|const| pointer are mutating. 93 94 // EC_KEY_new returns a fresh |EC_KEY| object or NULL on error. 95 OPENSSL_EXPORT EC_KEY *EC_KEY_new(void); 96 97 // EC_KEY_new_method acts the same as |EC_KEY_new|, but takes an explicit 98 // |ENGINE|. 99 OPENSSL_EXPORT EC_KEY *EC_KEY_new_method(const ENGINE *engine); 100 101 // EC_KEY_new_by_curve_name returns a fresh EC_KEY for group specified by |nid| 102 // or NULL on error. 103 OPENSSL_EXPORT EC_KEY *EC_KEY_new_by_curve_name(int nid); 104 105 // EC_KEY_free frees all the data owned by |key| and |key| itself. 106 OPENSSL_EXPORT void EC_KEY_free(EC_KEY *key); 107 108 // EC_KEY_dup returns a fresh copy of |src| or NULL on error. 109 OPENSSL_EXPORT EC_KEY *EC_KEY_dup(const EC_KEY *src); 110 111 // EC_KEY_up_ref increases the reference count of |key| and returns one. It does 112 // not mutate |key| for thread-safety purposes and may be used concurrently. 113 OPENSSL_EXPORT int EC_KEY_up_ref(EC_KEY *key); 114 115 // EC_KEY_is_opaque returns one if |key| is opaque and doesn't expose its key 116 // material. Otherwise it return zero. 117 OPENSSL_EXPORT int EC_KEY_is_opaque(const EC_KEY *key); 118 119 // EC_KEY_get0_group returns a pointer to the |EC_GROUP| object inside |key|. 120 OPENSSL_EXPORT const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key); 121 122 // EC_KEY_set_group sets the |EC_GROUP| object that |key| will use to |group|. 123 // It returns one on success and zero if |key| is already configured with a 124 // different group. 125 OPENSSL_EXPORT int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group); 126 127 // EC_KEY_get0_private_key returns a pointer to the private key inside |key|. 128 OPENSSL_EXPORT const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key); 129 130 // EC_KEY_set_private_key sets the private key of |key| to |priv|. It returns 131 // one on success and zero otherwise. |key| must already have had a group 132 // configured (see |EC_KEY_set_group| and |EC_KEY_new_by_curve_name|). 133 OPENSSL_EXPORT int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv); 134 135 // EC_KEY_get0_public_key returns a pointer to the public key point inside 136 // |key|. 137 OPENSSL_EXPORT const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key); 138 139 // EC_KEY_set_public_key sets the public key of |key| to |pub|, by copying it. 140 // It returns one on success and zero otherwise. |key| must already have had a 141 // group configured (see |EC_KEY_set_group| and |EC_KEY_new_by_curve_name|), and 142 // |pub| must also belong to that group. 143 OPENSSL_EXPORT int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub); 144 145 #define EC_PKEY_NO_PARAMETERS 0x001 146 #define EC_PKEY_NO_PUBKEY 0x002 147 148 // EC_KEY_get_enc_flags returns the encoding flags for |key|, which is a 149 // bitwise-OR of |EC_PKEY_*| values. 150 OPENSSL_EXPORT unsigned EC_KEY_get_enc_flags(const EC_KEY *key); 151 152 // EC_KEY_set_enc_flags sets the encoding flags for |key|, which is a 153 // bitwise-OR of |EC_PKEY_*| values. 154 OPENSSL_EXPORT void EC_KEY_set_enc_flags(EC_KEY *key, unsigned flags); 155 156 // EC_KEY_get_conv_form returns the conversation form that will be used by 157 // |key|. 158 OPENSSL_EXPORT point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key); 159 160 // EC_KEY_set_conv_form sets the conversion form to be used by |key|. 161 OPENSSL_EXPORT void EC_KEY_set_conv_form(EC_KEY *key, 162 point_conversion_form_t cform); 163 164 // EC_KEY_check_key performs several checks on |key| (possibly including an 165 // expensive check that the public key is in the primary subgroup). It returns 166 // one if all checks pass and zero otherwise. If it returns zero then detail 167 // about the problem can be found on the error stack. 168 OPENSSL_EXPORT int EC_KEY_check_key(const EC_KEY *key); 169 170 // EC_KEY_check_fips performs a signing pairwise consistency test (FIPS 140-2 171 // 4.9.2). It returns one if it passes and zero otherwise. 172 OPENSSL_EXPORT int EC_KEY_check_fips(const EC_KEY *key); 173 174 // EC_KEY_set_public_key_affine_coordinates sets the public key in |key| to 175 // (|x|, |y|). It returns one on success and zero otherwise. 176 OPENSSL_EXPORT int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, 177 const BIGNUM *x, 178 const BIGNUM *y); 179 180 // EC_KEY_key2buf encodes the public key in |key| to an allocated octet string 181 // and sets |*out_buf| to point to it. It returns the length of the encoded 182 // octet string or zero if an error occurred. 183 OPENSSL_EXPORT size_t EC_KEY_key2buf(EC_KEY *key, point_conversion_form_t form, 184 unsigned char **out_buf, BN_CTX *ctx); 185 186 187 // Key generation. 188 189 // EC_KEY_generate_key generates a random, private key, calculates the 190 // corresponding public key and stores both in |key|. It returns one on success 191 // or zero otherwise. 192 OPENSSL_EXPORT int EC_KEY_generate_key(EC_KEY *key); 193 194 // EC_KEY_generate_key_fips behaves like |EC_KEY_generate_key| but performs 195 // additional checks for FIPS compliance. 196 OPENSSL_EXPORT int EC_KEY_generate_key_fips(EC_KEY *key); 197 198 // EC_KEY_derive_from_secret deterministically derives a private key for |group| 199 // from an input secret using HKDF-SHA256. It returns a newly-allocated |EC_KEY| 200 // on success or NULL on error. |secret| must not be used in any other 201 // algorithm. If using a base secret for multiple operations, derive separate 202 // values with a KDF such as HKDF first. 203 // 204 // Note this function implements an arbitrary derivation scheme, rather than any 205 // particular standard one. New protocols are recommended to use X25519 and 206 // Ed25519, which have standard byte import functions. See 207 // |X25519_public_from_private| and |ED25519_keypair_from_seed|. 208 OPENSSL_EXPORT EC_KEY *EC_KEY_derive_from_secret(const EC_GROUP *group, 209 const uint8_t *secret, 210 size_t secret_len); 211 212 213 // Serialisation. 214 215 // EC_KEY_parse_private_key parses a DER-encoded ECPrivateKey structure (RFC 216 // 5915) from |cbs| and advances |cbs|. It returns a newly-allocated |EC_KEY| or 217 // NULL on error. If |group| is non-null, the parameters field of the 218 // ECPrivateKey may be omitted (but must match |group| if present). Otherwise, 219 // the parameters field is required. 220 OPENSSL_EXPORT EC_KEY *EC_KEY_parse_private_key(CBS *cbs, 221 const EC_GROUP *group); 222 223 // EC_KEY_marshal_private_key marshals |key| as a DER-encoded ECPrivateKey 224 // structure (RFC 5915) and appends the result to |cbb|. It returns one on 225 // success and zero on failure. |enc_flags| is a combination of |EC_PKEY_*| 226 // values and controls whether corresponding fields are omitted. 227 OPENSSL_EXPORT int EC_KEY_marshal_private_key(CBB *cbb, const EC_KEY *key, 228 unsigned enc_flags); 229 230 // EC_KEY_parse_curve_name parses a DER-encoded OBJECT IDENTIFIER as a curve 231 // name from |cbs| and advances |cbs|. It returns a newly-allocated |EC_GROUP| 232 // or NULL on error. 233 OPENSSL_EXPORT EC_GROUP *EC_KEY_parse_curve_name(CBS *cbs); 234 235 // EC_KEY_marshal_curve_name marshals |group| as a DER-encoded OBJECT IDENTIFIER 236 // and appends the result to |cbb|. It returns one on success and zero on 237 // failure. 238 OPENSSL_EXPORT int EC_KEY_marshal_curve_name(CBB *cbb, const EC_GROUP *group); 239 240 // EC_KEY_parse_parameters parses a DER-encoded ECParameters structure (RFC 241 // 5480) from |cbs| and advances |cbs|. It returns a newly-allocated |EC_GROUP| 242 // or NULL on error. It supports the namedCurve and specifiedCurve options, but 243 // use of specifiedCurve is deprecated. Use |EC_KEY_parse_curve_name| 244 // instead. 245 OPENSSL_EXPORT EC_GROUP *EC_KEY_parse_parameters(CBS *cbs); 246 247 248 // ex_data functions. 249 // 250 // These functions are wrappers. See |ex_data.h| for details. 251 252 OPENSSL_EXPORT int EC_KEY_get_ex_new_index(long argl, void *argp, 253 CRYPTO_EX_unused *unused, 254 CRYPTO_EX_dup *dup_unused, 255 CRYPTO_EX_free *free_func); 256 OPENSSL_EXPORT int EC_KEY_set_ex_data(EC_KEY *r, int idx, void *arg); 257 OPENSSL_EXPORT void *EC_KEY_get_ex_data(const EC_KEY *r, int idx); 258 259 260 // ECDSA method. 261 262 // ECDSA_FLAG_OPAQUE specifies that this ECDSA_METHOD does not expose its key 263 // material. This may be set if, for instance, it is wrapping some other crypto 264 // API, like a platform key store. 265 #define ECDSA_FLAG_OPAQUE 1 266 267 // ecdsa_method_st is a structure of function pointers for implementing ECDSA. 268 // See engine.h. 269 struct ecdsa_method_st { 270 struct openssl_method_common_st common; 271 272 void *app_data; 273 274 int (*init)(EC_KEY *key); 275 int (*finish)(EC_KEY *key); 276 277 // group_order_size returns the number of bytes needed to represent the order 278 // of the group. This is used to calculate the maximum size of an ECDSA 279 // signature in |ECDSA_size|. 280 size_t (*group_order_size)(const EC_KEY *key); 281 282 // sign matches the arguments and behaviour of |ECDSA_sign|. 283 int (*sign)(const uint8_t *digest, size_t digest_len, uint8_t *sig, 284 unsigned int *sig_len, EC_KEY *eckey); 285 286 int flags; 287 }; 288 289 290 // Deprecated functions. 291 292 // EC_KEY_set_asn1_flag does nothing. 293 OPENSSL_EXPORT void EC_KEY_set_asn1_flag(EC_KEY *key, int flag); 294 295 // d2i_ECPrivateKey parses an ASN.1, DER-encoded, private key from |len| bytes 296 // at |*inp|. If |out_key| is not NULL then, on exit, a pointer to the result 297 // is in |*out_key|. Note that, even if |*out_key| is already non-NULL on entry, 298 // it * will not be written to. Rather, a fresh |EC_KEY| is allocated and the 299 // previous * one is freed. On successful exit, |*inp| is advanced past the DER 300 // structure. It returns the result or NULL on error. 301 // 302 // On input, if |*out_key| is non-NULL and has a group configured, the 303 // parameters field may be omitted but must match that group if present. 304 // 305 // Use |EC_KEY_parse_private_key| instead. 306 OPENSSL_EXPORT EC_KEY *d2i_ECPrivateKey(EC_KEY **out_key, const uint8_t **inp, 307 long len); 308 309 // i2d_ECPrivateKey marshals an EC private key from |key| to an ASN.1, DER 310 // structure. If |outp| is not NULL then the result is written to |*outp| and 311 // |*outp| is advanced just past the output. It returns the number of bytes in 312 // the result, whether written or not, or a negative value on error. 313 // 314 // Use |EC_KEY_marshal_private_key| instead. 315 OPENSSL_EXPORT int i2d_ECPrivateKey(const EC_KEY *key, uint8_t **outp); 316 317 // d2i_ECParameters parses an ASN.1, DER-encoded, set of EC parameters from 318 // |len| bytes at |*inp|. If |out_key| is not NULL then, on exit, a pointer to 319 // the result is in |*out_key|. Note that, even if |*out_key| is already 320 // non-NULL on entry, it will not be written to. Rather, a fresh |EC_KEY| is 321 // allocated and the previous one is freed. On successful exit, |*inp| is 322 // advanced past the DER structure. It returns the result or NULL on error. 323 // 324 // Use |EC_KEY_parse_parameters| or |EC_KEY_parse_curve_name| instead. 325 OPENSSL_EXPORT EC_KEY *d2i_ECParameters(EC_KEY **out_key, const uint8_t **inp, 326 long len); 327 328 // i2d_ECParameters marshals EC parameters from |key| to an ASN.1, DER 329 // structure. If |outp| is not NULL then the result is written to |*outp| and 330 // |*outp| is advanced just past the output. It returns the number of bytes in 331 // the result, whether written or not, or a negative value on error. 332 // 333 // Use |EC_KEY_marshal_curve_name| instead. 334 OPENSSL_EXPORT int i2d_ECParameters(const EC_KEY *key, uint8_t **outp); 335 336 // o2i_ECPublicKey parses an EC point from |len| bytes at |*inp| into 337 // |*out_key|. Note that this differs from the d2i format in that |*out_key| 338 // must be non-NULL with a group set. On successful exit, |*inp| is advanced by 339 // |len| bytes. It returns |*out_key| or NULL on error. 340 // 341 // Use |EC_POINT_oct2point| instead. 342 OPENSSL_EXPORT EC_KEY *o2i_ECPublicKey(EC_KEY **out_key, const uint8_t **inp, 343 long len); 344 345 // i2o_ECPublicKey marshals an EC point from |key|. If |outp| is not NULL then 346 // the result is written to |*outp| and |*outp| is advanced just past the 347 // output. It returns the number of bytes in the result, whether written or 348 // not, or a negative value on error. 349 // 350 // Use |EC_POINT_point2cbb| instead. 351 OPENSSL_EXPORT int i2o_ECPublicKey(const EC_KEY *key, unsigned char **outp); 352 353 354 #if defined(__cplusplus) 355 } // extern C 356 357 extern "C++" { 358 359 BSSL_NAMESPACE_BEGIN 360 361 BORINGSSL_MAKE_DELETER(EC_KEY, EC_KEY_free) 362 BORINGSSL_MAKE_UP_REF(EC_KEY, EC_KEY_up_ref) 363 364 BSSL_NAMESPACE_END 365 366 } // extern C++ 367 368 #endif 369 370 #endif // OPENSSL_HEADER_EC_KEY_H 371