_ Git - BearSSL/blob - inc/bearssl_ec.h

   1 /*
   2  * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining
   5  * a copy of this software and associated documentation files (the
   6  * "Software"), to deal in the Software without restriction, including
   7  * without limitation the rights to use, copy, modify, merge, publish,
   8  * distribute, sublicense, and/or sell copies of the Software, and to
   9  * permit persons to whom the Software is furnished to do so, subject to
  10  * the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be
  13  * included in all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  19  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  20  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  22  * SOFTWARE.
  23  */
  24
  25 #ifndef BR_BEARSSL_EC_H__
  26 #define BR_BEARSSL_EC_H__
  27
  28 #include <stddef.h>
  29 #include <stdint.h>
  30
  31 /** \file bearssl_ec.h
  32  *
  33  * # Elliptic Curves
  34  *
  35  * This file documents the EC implementations provided with BearSSL, and
  36  * ECDSA.
  37  *
  38  * ## Elliptic Curve API
  39  *
  40  * Only "named curves" are supported. Each EC implementation supports
  41  * one or several named curves, identified by symbolic identifiers.
  42  * These identifiers are small integers, that correspond to the values
  43  * registered by the
  44  * [IANA](http://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-8).
  45  *
  46  * Since all currently defined elliptic curve identifiers are in the 0..31
  47  * range, it is convenient to encode support of some curves in a 32-bit
  48  * word, such that bit x corresponds to curve of identifier x.
  49  *
  50  * An EC implementation is incarnated by a `br_ec_impl` instance, that
  51  * offers the following fields:
  52  *
  53  *   - `supported_curves`
  54  *
  55  *      A 32-bit word that documents the identifiers of the curves supported
  56  *      by this implementation.
  57  *
  58  *   - `generator()`
  59  *
  60  *      Callback method that returns a pointer to the conventional generator
  61  *      point for that curve.
  62  *
  63  *   - `order()`
  64  *
  65  *      Callback method that returns a pointer to the subgroup order for
  66  *      that curve. That value uses unsigned big-endian encoding.
  67  *
  68  *   - `mul()`
  69  *
  70  *      Multiply a curve point with an integer.
  71  *
  72  *   - `mulgen()`
  73  *
  74  *      Multiply the curve generator with an integer. This may be faster
  75  *      than the generic `mul()`.
  76  *
  77  *   - `muladd()`
  78  *
  79  *      Multiply two curve points by two integers, and return the sum of
  80  *      the two products.
  81  *
  82  * All curve points are represented in uncompressed format. The `mul()`
  83  * and `muladd()` methods take care to validate that the provided points
  84  * are really part of the relevant curve subgroup.
  85  *
  86  * For all point multiplication functions, the following holds:
  87  *
  88  *   - Functions validate that the provided points are valid members
  89  *     of the relevant curve subgroup. An error is reported if that is
  90  *     not the case.
  91  *
  92  *   - Processing is constant-time, even if the point operands are not
  93  *     valid. This holds for both the source and resulting points, and
  94  *     the multipliers (integers). Only the byte length of the provided
  95  *     multiplier arrays (not their actual value length in bits) may
  96  *     leak through timing-based side channels.
  97  *
  98  *   - The multipliers (integers) MUST be lower than the subgroup order.
  99  *     If this property is not met, then the result is indeterminate,
 100  *     but an error value is not ncessearily returned.
 101  *
 102  *
 103  * ## ECDSA
 104  *
 105  * ECDSA signatures have two standard formats, called "raw" and "asn1".
 106  * Internally, such a signature is a pair of modular integers `(r,s)`.
 107  * The "raw" format is the concatenation of the unsigned big-endian
 108  * encodings of these two integers, possibly left-padded with zeros so
 109  * that they have the same encoded length. The "asn1" format is the
 110  * DER encoding of an ASN.1 structure that contains the two integer
 111  * values:
 112  *
 113  *     ECDSASignature ::= SEQUENCE {
 114  *         r   INTEGER,
 115  *         s   INTEGER
 116  *     }
 117  *
 118  * In general, in all of X.509 and SSL/TLS, the "asn1" format is used.
 119  * BearSSL offers ECDSA implementations for both formats; conversion
 120  * functions between the two formats are also provided. Conversion of a
 121  * "raw" format signature into "asn1" may enlarge a signature by no more
 122  * than 9 bytes for all supported curves; conversely, conversion of an
 123  * "asn1" signature to "raw" may expand the signature but the "raw"
 124  * length will never be more than twice the length of the "asn1" length
 125  * (and usually it will be shorter).
 126  *
 127  * Note that for a given signature, the "raw" format is not fully
 128  * deterministic, in that it does not enforce a minimal common length.
 129  */
 130
 131 /*
 132  * Standard curve ID. These ID are equal to the assigned numerical
 133  * identifiers assigned to these curves for TLS:
 134  *    http://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-8
 135  */
 136
 137 /** \brief Identifier for named curve sect163k1. */
 138 #define BR_EC_sect163k1           1
 139
 140 /** \brief Identifier for named curve sect163r1. */
 141 #define BR_EC_sect163r1           2
 142
 143 /** \brief Identifier for named curve sect163r2. */
 144 #define BR_EC_sect163r2           3
 145
 146 /** \brief Identifier for named curve sect193r1. */
 147 #define BR_EC_sect193r1           4
 148
 149 /** \brief Identifier for named curve sect193r2. */
 150 #define BR_EC_sect193r2           5
 151
 152 /** \brief Identifier for named curve sect233k1. */
 153 #define BR_EC_sect233k1           6
 154
 155 /** \brief Identifier for named curve sect233r1. */
 156 #define BR_EC_sect233r1           7
 157
 158 /** \brief Identifier for named curve sect239k1. */
 159 #define BR_EC_sect239k1           8
 160
 161 /** \brief Identifier for named curve sect283k1. */
 162 #define BR_EC_sect283k1           9
 163
 164 /** \brief Identifier for named curve sect283r1. */
 165 #define BR_EC_sect283r1          10
 166
 167 /** \brief Identifier for named curve sect409k1. */
 168 #define BR_EC_sect409k1          11
 169
 170 /** \brief Identifier for named curve sect409r1. */
 171 #define BR_EC_sect409r1          12
 172
 173 /** \brief Identifier for named curve sect571k1. */
 174 #define BR_EC_sect571k1          13
 175
 176 /** \brief Identifier for named curve sect571r1. */
 177 #define BR_EC_sect571r1          14
 178
 179 /** \brief Identifier for named curve secp160k1. */
 180 #define BR_EC_secp160k1          15
 181
 182 /** \brief Identifier for named curve secp160r1. */
 183 #define BR_EC_secp160r1          16
 184
 185 /** \brief Identifier for named curve secp160r2. */
 186 #define BR_EC_secp160r2          17
 187
 188 /** \brief Identifier for named curve secp192k1. */
 189 #define BR_EC_secp192k1          18
 190
 191 /** \brief Identifier for named curve secp192r1. */
 192 #define BR_EC_secp192r1          19
 193
 194 /** \brief Identifier for named curve secp224k1. */
 195 #define BR_EC_secp224k1          20
 196
 197 /** \brief Identifier for named curve secp224r1. */
 198 #define BR_EC_secp224r1          21
 199
 200 /** \brief Identifier for named curve secp256k1. */
 201 #define BR_EC_secp256k1          22
 202
 203 /** \brief Identifier for named curve secp256r1. */
 204 #define BR_EC_secp256r1          23
 205
 206 /** \brief Identifier for named curve secp384r1. */
 207 #define BR_EC_secp384r1          24
 208
 209 /** \brief Identifier for named curve secp521r1. */
 210 #define BR_EC_secp521r1          25
 211
 212 /** \brief Identifier for named curve brainpoolP256r1. */
 213 #define BR_EC_brainpoolP256r1    26
 214
 215 /** \brief Identifier for named curve brainpoolP384r1. */
 216 #define BR_EC_brainpoolP384r1    27
 217
 218 /** \brief Identifier for named curve brainpoolP512r1. */
 219 #define BR_EC_brainpoolP512r1    28
 220
 221 /**
 222  * \brief Structure for an EC public key.
 223  */
 224 typedef struct {
 225         /** \brief Identifier for the curve used by this key. */
 226         int curve;
 227         /** \brief Public curve point (uncompressed format). */
 228         unsigned char *q;
 229         /** \brief Length of public curve point (in bytes). */
 230         size_t qlen;
 231 } br_ec_public_key;
 232
 233 /**
 234  * \brief Structure for an EC private key.
 235  *
 236  * The private key is an integer modulo the curve subgroup order. The
 237  * encoding below tolerates extra leading zeros. In general, it is
 238  * recommended that the private key has the same length as the curve
 239  * subgroup order.
 240  */
 241 typedef struct {
 242         /** \brief Identifier for the curve used by this key. */
 243         int curve;
 244         /** \brief Private key (integer, unsigned big-endian encoding). */
 245         unsigned char *x;
 246         /** \brief Private key length (in bytes). */
 247         size_t xlen;
 248 } br_ec_private_key;
 249
 250 /**
 251  * \brief Type for an EC implementation.
 252  */
 253 typedef struct {
 254         /**
 255          * \brief Supported curves.
 256          *
 257          * This word is a bitfield: bit `x` is set if the curve of ID `x`
 258          * is supported. E.g. an implementation supporting both NIST P-256
 259          * (secp256r1, ID 23) and NIST P-384 (secp384r1, ID 24) will have
 260          * value `0x01800000` in this field.
 261          */
 262         uint32_t supported_curves;
 263
 264         /**
 265          * \brief Get the conventional generator.
 266          *
 267          * This function returns the conventional generator (encoded
 268          * curve point) for the specified curve. This function MUST NOT
 269          * be called if the curve is not supported.
 270          *
 271          * \param curve   curve identifier.
 272          * \param len     receiver for the encoded generator length (in bytes).
 273          * \return  the encoded generator.
 274          */
 275         const unsigned char *(*generator)(int curve, size_t *len);
 276
 277         /**
 278          * \brief Get the subgroup order.
 279          *
 280          * This function returns the order of the subgroup generated by
 281          * the conventional generator, for the specified curve. Unsigned
 282          * big-endian encoding is used. This function MUST NOT be called
 283          * if the curve is not supported.
 284          *
 285          * \param curve   curve identifier.
 286          * \param len     receiver for the encoded order length (in bytes).
 287          * \return  the encoded order.
 288          */
 289         const unsigned char *(*order)(int curve, size_t *len);
 290
 291         /**
 292          * \brief Multiply a curve point by an integer.
 293          *
 294          * The source point is provided in array `G` (of size `Glen` bytes);
 295          * the multiplication result is written over it. The multiplier
 296          * `x` (of size `xlen` bytes) uses unsigned big-endian encoding.
 297          *
 298          * Rules:
 299          *
 300          *   - The specified curve MUST be supported.
 301          *
 302          *   - The source point must be a valid point on the relevant curve
 303          *     subgroup (and not the "point at infinity" either). If this is
 304          *     not the case, then this function returns an error (0).
 305          *
 306          *   - The multiplier integer MUST be non-zero and less than the
 307          *     curve subgroup order. If this property does not hold, then
 308          *     the result is indeterminate and an error code is not
 309          *     guaranteed.
 310          *
 311          * Returned value is 1 on success, 0 on error. On error, the
 312          * contents of `G` are indeterminate.
 313          *
 314          * \param G       point to multiply.
 315          * \param Glen    length of the encoded point (in bytes).
 316          * \param x       multiplier (unsigned big-endian).
 317          * \param xlen    multiplier length (in bytes).
 318          * \param curve   curve identifier.
 319          * \return  1 on success, 0 on error.
 320          */
 321         uint32_t (*mul)(unsigned char *G, size_t Glen,
 322                 const unsigned char *x, size_t xlen, int curve);
 323
 324         /**
 325          * \brief Multiply the generator by an integer.
 326          *
 327          * The multiplier MUST be non-zero and less than the curve
 328          * subgroup order. Results are indeterminate if this property
 329          * does not hold.
 330          *
 331          * \param R       output buffer for the point.
 332          * \param x       multiplier (unsigned big-endian).
 333          * \param xlen    multiplier length (in bytes).
 334          * \param curve   curve identifier.
 335          * \return  encoded result point length (in bytes).
 336          */
 337         size_t (*mulgen)(unsigned char *R,
 338                 const unsigned char *x, size_t xlen, int curve);
 339
 340         /**
 341          * \brief Multiply two points by two integers and add the
 342          * results.
 343          *
 344          * The point `x*A + y*B` is computed and written back in the `A`
 345          * array.
 346          *
 347          * Rules:
 348          *
 349          *   - The specified curve MUST be supported.
 350          *
 351          *   - The source points (`A` and `B`)  must be valid points on
 352          *     the relevant curve subgroup (and not the "point at
 353          *     infinity" either). If this is not the case, then this
 354          *     function returns an error (0).
 355          *
 356          *   - If the `B` pointer is `NULL`, then the conventional
 357          *     subgroup generator is used. With some implementations,
 358          *     this may be faster than providing a pointer to the
 359          *     generator.
 360          *
 361          *   - The multiplier integers (`x` and `y`) MUST be non-zero
 362          *     and less than the curve subgroup order. If either integer
 363          *     is zero, then an error is reported, but if one of them is
 364          *     not lower than the subgroup order, then the result is
 365          *     indeterminate and an error code is not guaranteed.
 366          *
 367          *   - If the final result is the point at infinity, then an
 368          *     error is returned.
 369          *
 370          * Returned value is 1 on success, 0 on error. On error, the
 371          * contents of `A` are indeterminate.
 372          *
 373          * \param A       first point to multiply.
 374          * \param B       second point to multiply (`NULL` for the generator).
 375          * \param len     common length of the encoded points (in bytes).
 376          * \param x       multiplier for `A` (unsigned big-endian).
 377          * \param xlen    length of multiplier for `A` (in bytes).
 378          * \param y       multiplier for `A` (unsigned big-endian).
 379          * \param ylen    length of multiplier for `A` (in bytes).
 380          * \param curve   curve identifier.
 381          * \return  1 on success, 0 on error.
 382          */
 383         uint32_t (*muladd)(unsigned char *A, const unsigned char *B, size_t len,
 384                 const unsigned char *x, size_t xlen,
 385                 const unsigned char *y, size_t ylen, int curve);
 386 } br_ec_impl;
 387
 388 /**
 389  * \brief EC implementation "i31".
 390  *
 391  * This implementation internally uses generic code for modular integers,
 392  * with a representation as sequences of 31-bit words. It supports secp256r1,
 393  * secp384r1 and secp521r1 (aka NIST curves P-256, P-384 and P-521).
 394  */
 395 extern const br_ec_impl br_ec_prime_i31;
 396
 397 /**
 398  * \brief EC implementation "i15".
 399  *
 400  * This implementation internally uses generic code for modular integers,
 401  * with a representation as sequences of 15-bit words. It supports secp256r1,
 402  * secp384r1 and secp521r1 (aka NIST curves P-256, P-384 and P-521).
 403  */
 404 extern const br_ec_impl br_ec_prime_i15;
 405
 406 /**
 407  * \brief EC implementation "i15" for P-256.
 408  *
 409  * This implementation uses specialised code for curve secp256r1 (also
 410  * known as NIST P-256), with Karatsuba decomposition, and fast modular
 411  * reduction thanks to the field modulus special format. Only 32-bit
 412  * multiplications are used (with 32-bit results, not 64-bit).
 413  */
 414 extern const br_ec_impl br_ec_p256_i15;
 415
 416 /**
 417  * \brief Convert a signature from "raw" to "asn1".
 418  *
 419  * Conversion is done "in place" and the new length is returned.
 420  * Conversion may enlarge the signature, but by no more than 9 bytes at
 421  * most. On error, 0 is returned (error conditions include an odd raw
 422  * signature length, or an oversized integer).
 423  *
 424  * \param sig       signature to convert.
 425  * \param sig_len   signature length (in bytes).
 426  * \return  the new signature length, or 0 on error.
 427  */
 428 size_t br_ecdsa_raw_to_asn1(void *sig, size_t sig_len);
 429
 430 /**
 431  * \brief Convert a signature from "asn1" to "raw".
 432  *
 433  * Conversion is done "in place" and the new length is returned.
 434  * Conversion may enlarge the signature, but the new signature length
 435  * will be less than twice the source length at most. On error, 0 is
 436  * returned (error conditions include an invalid ASN.1 structure or an
 437  * oversized integer).
 438  *
 439  * \param sig       signature to convert.
 440  * \param sig_len   signature length (in bytes).
 441  * \return  the new signature length, or 0 on error.
 442  */
 443 size_t br_ecdsa_asn1_to_raw(void *sig, size_t sig_len);
 444
 445 /**
 446  * \brief Type for an ECDSA signer function.
 447  *
 448  * A pointer to the EC implementation is provided. The hash value is
 449  * assumed to have the length inferred from the designated hash function
 450  * class.
 451  *
 452  * Signature is written in the buffer pointed to by `sig`, and the length
 453  * (in bytes) is returned. On error, nothing is written in the buffer,
 454  * and 0 is returned. This function returns 0 if the specified curve is
 455  * not supported by the provided EC implementation.
 456  *
 457  * The signature format is either "raw" or "asn1", depending on the
 458  * implementation; maximum length is predictable from the implemented
 459  * curve:
 460  *
 461  * | curve      | raw | asn1 |
 462  * | :--------- | --: | ---: |
 463  * | NIST P-256 |  64 |   72 |
 464  * | NIST P-384 |  96 |  104 |
 465  * | NIST P-521 | 132 |  139 |
 466  *
 467  * \param impl         EC implementation to use.
 468  * \param hf           hash function used to process the data.
 469  * \param hash_value   signed data (hashed).
 470  * \param sk           EC private key.
 471  * \param sig          destination buffer.
 472  * \return  the signature length (in bytes), or 0 on error.
 473  */
 474 typedef size_t (*br_ecdsa_sign)(const br_ec_impl *impl,
 475         const br_hash_class *hf, const void *hash_value,
 476         const br_ec_private_key *sk, void *sig);
 477
 478 /**
 479  * \brief Type for an ECDSA signature verification function.
 480  *
 481  * A pointer to the EC implementation is provided. The hashed value,
 482  * computed over the purportedly signed data, is also provided with
 483  * its length.
 484  *
 485  * The signature format is either "raw" or "asn1", depending on the
 486  * implementation.
 487  *
 488  * Returned value is 1 on success (valid signature), 0 on error. This
 489  * function returns 0 if the specified curve is not supported by the
 490  * provided EC implementation.
 491  *
 492  * \param impl       EC implementation to use.
 493  * \param hash       signed data (hashed).
 494  * \param hash_len   hash value length (in bytes).
 495  * \param pk         EC public key.
 496  * \param sig        signature.
 497  * \param sig_len    signature length (in bytes).
 498  * \return  1 on success, 0 on error.
 499  */
 500 typedef uint32_t (*br_ecdsa_vrfy)(const br_ec_impl *impl,
 501         const void *hash, size_t hash_len,
 502         const br_ec_public_key *pk, const void *sig, size_t sig_len);
 503
 504 /**
 505  * \brief ECDSA signature generator, "i31" implementation, "asn1" format.
 506  *
 507  * \see br_ecdsa_sign()
 508  *
 509  * \param impl         EC implementation to use.
 510  * \param hf           hash function used to process the data.
 511  * \param hash_value   signed data (hashed).
 512  * \param sk           EC private key.
 513  * \param sig          destination buffer.
 514  * \return  the signature length (in bytes), or 0 on error.
 515  */
 516 size_t br_ecdsa_i31_sign_asn1(const br_ec_impl *impl,
 517         const br_hash_class *hf, const void *hash_value,
 518         const br_ec_private_key *sk, void *sig);
 519
 520 /**
 521  * \brief ECDSA signature generator, "i31" implementation, "raw" format.
 522  *
 523  * \see br_ecdsa_sign()
 524  *
 525  * \param impl         EC implementation to use.
 526  * \param hf           hash function used to process the data.
 527  * \param hash_value   signed data (hashed).
 528  * \param sk           EC private key.
 529  * \param sig          destination buffer.
 530  * \return  the signature length (in bytes), or 0 on error.
 531  */
 532 size_t br_ecdsa_i31_sign_raw(const br_ec_impl *impl,
 533         const br_hash_class *hf, const void *hash_value,
 534         const br_ec_private_key *sk, void *sig);
 535
 536 /**
 537  * \brief ECDSA signature verifier, "i31" implementation, "asn1" format.
 538  *
 539  * \see br_ecdsa_vrfy()
 540  *
 541  * \param impl       EC implementation to use.
 542  * \param hash       signed data (hashed).
 543  * \param hash_len   hash value length (in bytes).
 544  * \param pk         EC public key.
 545  * \param sig        signature.
 546  * \param sig_len    signature length (in bytes).
 547  * \return  1 on success, 0 on error.
 548  */
 549 uint32_t br_ecdsa_i31_vrfy_asn1(const br_ec_impl *impl,
 550         const void *hash, size_t hash_len,
 551         const br_ec_public_key *pk, const void *sig, size_t sig_len);
 552
 553 /**
 554  * \brief ECDSA signature verifier, "i31" implementation, "raw" format.
 555  *
 556  * \see br_ecdsa_vrfy()
 557  *
 558  * \param impl       EC implementation to use.
 559  * \param hash       signed data (hashed).
 560  * \param hash_len   hash value length (in bytes).
 561  * \param pk         EC public key.
 562  * \param sig        signature.
 563  * \param sig_len    signature length (in bytes).
 564  * \return  1 on success, 0 on error.
 565  */
 566 uint32_t br_ecdsa_i31_vrfy_raw(const br_ec_impl *impl,
 567         const void *hash, size_t hash_len,
 568         const br_ec_public_key *pk, const void *sig, size_t sig_len);
 569
 570 /**
 571  * \brief ECDSA signature generator, "i15" implementation, "asn1" format.
 572  *
 573  * \see br_ecdsa_sign()
 574  *
 575  * \param impl         EC implementation to use.
 576  * \param hf           hash function used to process the data.
 577  * \param hash_value   signed data (hashed).
 578  * \param sk           EC private key.
 579  * \param sig          destination buffer.
 580  * \return  the signature length (in bytes), or 0 on error.
 581  */
 582 size_t br_ecdsa_i15_sign_asn1(const br_ec_impl *impl,
 583         const br_hash_class *hf, const void *hash_value,
 584         const br_ec_private_key *sk, void *sig);
 585
 586 /**
 587  * \brief ECDSA signature generator, "i15" implementation, "raw" format.
 588  *
 589  * \see br_ecdsa_sign()
 590  *
 591  * \param impl         EC implementation to use.
 592  * \param hf           hash function used to process the data.
 593  * \param hash_value   signed data (hashed).
 594  * \param sk           EC private key.
 595  * \param sig          destination buffer.
 596  * \return  the signature length (in bytes), or 0 on error.
 597  */
 598 size_t br_ecdsa_i15_sign_raw(const br_ec_impl *impl,
 599         const br_hash_class *hf, const void *hash_value,
 600         const br_ec_private_key *sk, void *sig);
 601
 602 /**
 603  * \brief ECDSA signature verifier, "i15" implementation, "asn1" format.
 604  *
 605  * \see br_ecdsa_vrfy()
 606  *
 607  * \param impl       EC implementation to use.
 608  * \param hash       signed data (hashed).
 609  * \param hash_len   hash value length (in bytes).
 610  * \param pk         EC public key.
 611  * \param sig        signature.
 612  * \param sig_len    signature length (in bytes).
 613  * \return  1 on success, 0 on error.
 614  */
 615 uint32_t br_ecdsa_i15_vrfy_asn1(const br_ec_impl *impl,
 616         const void *hash, size_t hash_len,
 617         const br_ec_public_key *pk, const void *sig, size_t sig_len);
 618
 619 /**
 620  * \brief ECDSA signature verifier, "i15" implementation, "raw" format.
 621  *
 622  * \see br_ecdsa_vrfy()
 623  *
 624  * \param impl       EC implementation to use.
 625  * \param hash       signed data (hashed).
 626  * \param hash_len   hash value length (in bytes).
 627  * \param pk         EC public key.
 628  * \param sig        signature.
 629  * \param sig_len    signature length (in bytes).
 630  * \return  1 on success, 0 on error.
 631  */
 632 uint32_t br_ecdsa_i15_vrfy_raw(const br_ec_impl *impl,
 633         const void *hash, size_t hash_len,
 634         const br_ec_public_key *pk, const void *sig, size_t sig_len);
 635
 636 #endif