/*

 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")

 *

 * SPDX-License-Identifier: MPL-2.0

 *

 * This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, you can obtain one at https://mozilla.org/MPL/2.0/.

 *

 * See the COPYRIGHT file distributed with this work for additional

 * information regarding copyright ownership.

 */

#include <stdio.h>

#include <openssl/err.h>

#include <openssl/evp.h>

#include <openssl/opensslv.h>

#include <isc/md.h>

#include <isc/ossl_wrap.h>

#include <isc/util.h>

#include "openssl_shim.h"

isc_md_t *

isc_md_new(void) {

  isc_md_t *md = EVP_MD_CTX_new();

  RUNTIME_CHECK(md != NULL);

  return md;

}

void

isc_md_free(isc_md_t *md) {

  if (md == NULL) {

    return;

  }

  EVP_MD_CTX_free(md);

}

isc_result_t

isc_md_init(isc_md_t *md, isc_md_type_t type) {

  EVP_MD *evp;

  REQUIRE(md != NULL);

  REQUIRE(type < ISC_MD_MAX);

  evp = isc__crypto_md[type];

  if (evp == NULL) {

    return ISC_R_NOTIMPLEMENTED;

  }

  if (EVP_DigestInit_ex(md, evp, NULL) != 1) {

    ERR_clear_error();

    return ISC_R_CRYPTOFAILURE;

  }

  return ISC_R_SUCCESS;

}

isc_result_t

isc_md_reset(isc_md_t *md) {

  REQUIRE(md != NULL);

  if (EVP_MD_CTX_reset(md) != 1) {

    ERR_clear_error();

    return ISC_R_CRYPTOFAILURE;

  }

  return ISC_R_SUCCESS;

}

isc_result_t

isc_md_update(isc_md_t *md, const unsigned char *buf, const size_t len) {

  REQUIRE(md != NULL);

  if (buf == NULL || len == 0) {

    return ISC_R_SUCCESS;

  }

  if (EVP_DigestUpdate(md, buf, len) != 1) {

    ERR_clear_error();

    return ISC_R_CRYPTOFAILURE;

  }

  return ISC_R_SUCCESS;

}

isc_result_t

isc_md_final(isc_md_t *md, unsigned char *digest, unsigned int *digestlen) {

  REQUIRE(md != NULL);

  REQUIRE(digest != NULL);

  if (EVP_DigestFinal_ex(md, digest, digestlen) != 1) {

    ERR_clear_error();

    return ISC_R_CRYPTOFAILURE;

  }

  return ISC_R_SUCCESS;

}

size_t

isc_md_get_size(isc_md_t *md) {

  REQUIRE(md != NULL);

  return EVP_MD_CTX_size(md);

}

size_t

isc_md_get_block_size(isc_md_t *md) {

  REQUIRE(md != NULL);

  return EVP_MD_CTX_block_size(md);

}

size_t

isc_md_type_get_block_size(isc_md_type_t type) {

  EVP_MD *evp;

  REQUIRE(type < ISC_MD_MAX);

  STATIC_ASSERT(ISC_MAX_MD_SIZE >= EVP_MAX_MD_SIZE,

          "Change ISC_MAX_MD_SIZE to be greater than or equal to "

          "EVP_MAX_MD_SIZE");

  evp = isc__crypto_md[type];

  if (evp != NULL) {

    return (size_t)EVP_MD_block_size(evp);

  }

  return ISC_MAX_MD_SIZE;

}

isc_result_t

isc_md(isc_md_type_t type, const unsigned char *buf, const size_t len,

       unsigned char *digest, unsigned int *digestlen) {

  isc_md_t *md;

  isc_result_t res;

  md = isc_md_new();

  res = isc_md_init(md, type);

  if (res != ISC_R_SUCCESS) {

    goto end;

  }

  res = isc_md_update(md, buf, len);

  if (res != ISC_R_SUCCESS) {

    goto end;

  }

  res = isc_md_final(md, digest, digestlen);

  if (res != ISC_R_SUCCESS) {

    goto end;

  }

end:

  isc_md_free(md);

  return res;

}