/* $OpenBSD: ecs_lib.c,v 1.13 2018/04/14 07:09:21 tb Exp $ */

/* ====================================================================

 * Copyright (c) 1998-2005 The OpenSSL Project.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 *

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in

 *    the documentation and/or other materials provided with the

 *    distribution.

 *

 * 3. All advertising materials mentioning features or use of this

 *    software must display the following acknowledgment:

 *    "This product includes software developed by the OpenSSL Project

 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"

 *

 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to

 *    endorse or promote products derived from this software without

 *    prior written permission. For written permission, please contact

 *    openssl-core@OpenSSL.org.

 *

 * 5. Products derived from this software may not be called "OpenSSL"

 *    nor may "OpenSSL" appear in their names without prior written

 *    permission of the OpenSSL Project.

 *

 * 6. Redistributions of any form whatsoever must retain the following

 *    acknowledgment:

 *    "This product includes software developed by the OpenSSL Project

 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"

 *

 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY

 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR

 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED

 * OF THE POSSIBILITY OF SUCH DAMAGE.

 * ====================================================================

 *

 * This product includes cryptographic software written by Eric Young

 * (eay@cryptsoft.com).  This product includes software written by Tim

 * Hudson (tjh@cryptsoft.com).

 *

 */

#include <string.h>

#include <openssl/opensslconf.h>

#include "ecs_locl.h"

#ifndef OPENSSL_NO_ENGINE

#include <openssl/engine.h>

#endif

#include <openssl/err.h>

#include <openssl/bn.h>

static const ECDSA_METHOD *default_ECDSA_method = NULL;

static void *ecdsa_data_new(void);

static void *ecdsa_data_dup(void *);

static void  ecdsa_data_free(void *);

void

ECDSA_set_default_method(const ECDSA_METHOD *meth)

{

  default_ECDSA_method = meth;

}

const ECDSA_METHOD *

ECDSA_get_default_method(void)

{

  if (!default_ECDSA_method) {

    default_ECDSA_method = ECDSA_OpenSSL();

  }

  return default_ECDSA_method;

}

int

ECDSA_set_method(EC_KEY *eckey, const ECDSA_METHOD *meth)

{

  ECDSA_DATA *ecdsa;

  ecdsa = ecdsa_check(eckey);

  if (ecdsa == NULL)

    return 0;

#ifndef OPENSSL_NO_ENGINE

  ENGINE_finish(ecdsa->engine);

  ecdsa->engine = NULL;

#endif

  ecdsa->meth = meth;

  return 1;

}

static ECDSA_DATA *

ECDSA_DATA_new_method(ENGINE *engine)

{

  ECDSA_DATA *ret;

  ret = malloc(sizeof(ECDSA_DATA));

  if (ret == NULL) {

    ECDSAerror(ERR_R_MALLOC_FAILURE);

    return (NULL);

  }

  ret->init = NULL;

  ret->meth = ECDSA_get_default_method();

  ret->engine = engine;

#ifndef OPENSSL_NO_ENGINE

  if (!ret->engine)

    ret->engine = ENGINE_get_default_ECDSA();

  if (ret->engine) {

    ret->meth = ENGINE_get_ECDSA(ret->engine);

    if (ret->meth == NULL) {

      ECDSAerror(ERR_R_ENGINE_LIB);

      ENGINE_finish(ret->engine);

      free(ret);

      return NULL;

    }

  }

#endif

  ret->flags = ret->meth->flags;

  CRYPTO_new_ex_data(CRYPTO_EX_INDEX_ECDSA, ret, &ret->ex_data);

  return (ret);

}

static void *

ecdsa_data_new(void)

{

  return (void *)ECDSA_DATA_new_method(NULL);

}

static void *

ecdsa_data_dup(void *data)

{

  ECDSA_DATA *r = (ECDSA_DATA *)data;

  /* XXX: dummy operation */

  if (r == NULL)

    return NULL;

  return ecdsa_data_new();

}

static void

ecdsa_data_free(void *data)

{

  ECDSA_DATA *r = (ECDSA_DATA *)data;

#ifndef OPENSSL_NO_ENGINE

  ENGINE_finish(r->engine);

#endif

  CRYPTO_free_ex_data(CRYPTO_EX_INDEX_ECDSA, r, &r->ex_data);

  freezero(r, sizeof(ECDSA_DATA));

}

ECDSA_DATA *

ecdsa_check(EC_KEY *key)

{

  ECDSA_DATA *ecdsa_data;

  void *data = EC_KEY_get_key_method_data(key, ecdsa_data_dup,

      ecdsa_data_free, ecdsa_data_free);

  if (data == NULL) {

    ecdsa_data = (ECDSA_DATA *)ecdsa_data_new();

    if (ecdsa_data == NULL)

      return NULL;

    data = EC_KEY_insert_key_method_data(key, (void *)ecdsa_data,

        ecdsa_data_dup, ecdsa_data_free, ecdsa_data_free);

    if (data != NULL) {

      /* Another thread raced us to install the key_method

       * data and won. */

      ecdsa_data_free(ecdsa_data);

      ecdsa_data = (ECDSA_DATA *)data;

    }

  } else

    ecdsa_data = (ECDSA_DATA *)data;

  return ecdsa_data;

}

int

ECDSA_size(const EC_KEY *r)

{

  int ret, i;

  ASN1_INTEGER bs;

  BIGNUM  *order = NULL;

  unsigned char buf[4];

  const EC_GROUP *group;

  if (r == NULL)

    return 0;

  group = EC_KEY_get0_group(r);

  if (group == NULL)

    return 0;

  if ((order = BN_new()) == NULL)

    return 0;

  if (!EC_GROUP_get_order(group, order, NULL)) {

    BN_clear_free(order);

    return 0;

  }

  i = BN_num_bits(order);

  bs.length = (i + 7) / 8;

  bs.data = buf;

  bs.type = V_ASN1_INTEGER;

  /* If the top bit is set the asn1 encoding is 1 larger. */

  buf[0] = 0xff;

  i = i2d_ASN1_INTEGER(&bs, NULL);

  i += i; /* r and s */

  ret = ASN1_object_size(1, i, V_ASN1_SEQUENCE);

  BN_clear_free(order);

  return (ret);

}

int

ECDSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,

    CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)

{

  return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_ECDSA, argl, argp,

      new_func, dup_func, free_func);

}

int

ECDSA_set_ex_data(EC_KEY *d, int idx, void *arg)

{

  ECDSA_DATA *ecdsa;

  ecdsa = ecdsa_check(d);

  if (ecdsa == NULL)

    return 0;

  return (CRYPTO_set_ex_data(&ecdsa->ex_data, idx, arg));

}

void *

ECDSA_get_ex_data(EC_KEY *d, int idx)

{

  ECDSA_DATA *ecdsa;

  ecdsa = ecdsa_check(d);

  if (ecdsa == NULL)

    return NULL;

  return (CRYPTO_get_ex_data(&ecdsa->ex_data, idx));

}