/*

 * Copyright (C) 2019 Red Hat, Inc.

 *

 * Author: Daiki Ueno

 *

 * This file is part of GNUTLS.

 *

 * The GNUTLS library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public License

 * as published by the Free Software Foundation; either version 2.1 of

 * the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful, but

 * WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with this program.  If not, see <https://www.gnu.org/licenses/>

 *

 */

#if HAVE_CONFIG_H

#include "config.h"

#endif

#include "ecdsa-compute-k.h"

#include "dsa-compute-k.h"

#include "gnutls_int.h"

static inline int _gnutls_ecc_curve_to_dsa_q(mpz_t *q, gnutls_ecc_curve_t curve)

{

  switch (curve) {

#ifdef ENABLE_NON_SUITEB_CURVES

  case GNUTLS_ECC_CURVE_SECP192R1:

    mpz_init_set_str(*q,

         "FFFFFFFFFFFFFFFFFFFFFFFF99DEF836"

         "146BC9B1B4D22831",

         16);

    return 0;

  case GNUTLS_ECC_CURVE_SECP224R1:

    mpz_init_set_str(*q,

         "FFFFFFFFFFFFFFFFFFFFFFFFFFFF16A2"

         "E0B8F03E13DD29455C5C2A3D",

         16);

    return 0;

#endif

  case GNUTLS_ECC_CURVE_SECP256R1:

    mpz_init_set_str(*q,

         "FFFFFFFF00000000FFFFFFFFFFFFFFFF"

         "BCE6FAADA7179E84F3B9CAC2FC632551",

         16);

    return 0;

  case GNUTLS_ECC_CURVE_SECP384R1:

    mpz_init_set_str(*q,

         "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"

         "FFFFFFFFFFFFFFFFC7634D81F4372DDF"

         "581A0DB248B0A77AECEC196ACCC52973",

         16);

    return 0;

  case GNUTLS_ECC_CURVE_SECP521R1:

    mpz_init_set_str(*q,

         "1FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"

         "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"

         "FFA51868783BF2F966B7FCC0148F709A"

         "5D03BB5C9B8899C47AEBB6FB71E91386"

         "409",

         16);

    return 0;

  default:

    return gnutls_assert_val(

      GNUTLS_E_UNSUPPORTED_SIGNATURE_ALGORITHM);

  }

}

int _gnutls_ecdsa_compute_k(mpz_t k, gnutls_ecc_curve_t curve, const mpz_t x,

          gnutls_mac_algorithm_t mac, const uint8_t *digest,

          size_t length)

{

  mpz_t q;

  int ret;

  ret = _gnutls_ecc_curve_to_dsa_q(&q, curve);

  if (ret < 0)

    return gnutls_assert_val(ret);

  ret = _gnutls_dsa_compute_k(k, q, x, mac, digest, length);

  mpz_clear(q);

  return ret;

}