/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)

 * All rights reserved.

 *

 * This package is an SSL implementation written

 * by Eric Young (eay@cryptsoft.com).

 * The implementation was written so as to conform with Netscapes SSL.

 *

 * This library is free for commercial and non-commercial use as long as

 * the following conditions are aheared to.  The following conditions

 * apply to all code found in this distribution, be it the RC4, RSA,

 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation

 * included with this distribution is covered by the same copyright terms

 * except that the holder is Tim Hudson (tjh@cryptsoft.com).

 *

 * Copyright remains Eric Young's, and as such any Copyright notices in

 * the code are not to be removed.

 * If this package is used in a product, Eric Young should be given attribution

 * as the author of the parts of the library used.

 * This can be in the form of a textual message at program startup or

 * in documentation (online or textual) provided with the package.

 *

 * 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 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 acknowledgement:

 *    "This product includes cryptographic software written by

 *     Eric Young (eay@cryptsoft.com)"

 *    The word 'cryptographic' can be left out if the rouines from the library

 *    being used are not cryptographic related :-).

 * 4. If you include any Windows specific code (or a derivative thereof) from

 *    the apps directory (application code) you must include an acknowledgement:

 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"

 *

 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND

 * ANY EXPRESS 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 AUTHOR OR 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.

 *

 * The licence and distribution terms for any publically available version or

 * derivative of this code cannot be changed.  i.e. this code cannot simply be

 * copied and put under another distribution licence

 * [including the GNU Public Licence.] */

#include <openssl/digest.h>

#include <assert.h>

#include <string.h>

#include <openssl/err.h>

#include <openssl/mem.h>

#include "internal.h"

#include "../../internal.h"

int EVP_MD_type(const EVP_MD *md) { return md->type; }

int EVP_MD_nid(const EVP_MD *md) { return EVP_MD_type(md); }

uint32_t EVP_MD_flags(const EVP_MD *md) { return md->flags; }

size_t EVP_MD_size(const EVP_MD *md) { return md->md_size; }

size_t EVP_MD_block_size(const EVP_MD *md) { return md->block_size; }

void EVP_MD_CTX_init(EVP_MD_CTX *ctx) {

  OPENSSL_memset(ctx, 0, sizeof(EVP_MD_CTX));

}

EVP_MD_CTX *EVP_MD_CTX_new(void) {

  EVP_MD_CTX *ctx = OPENSSL_malloc(sizeof(EVP_MD_CTX));

  if (ctx) {

    EVP_MD_CTX_init(ctx);

  }

  return ctx;

}

EVP_MD_CTX *EVP_MD_CTX_create(void) { return EVP_MD_CTX_new(); }

int EVP_MD_CTX_cleanup(EVP_MD_CTX *ctx) {

  OPENSSL_free(ctx->md_data);

  assert(ctx->pctx == NULL || ctx->pctx_ops != NULL);

  if (ctx->pctx_ops) {

    ctx->pctx_ops->free(ctx->pctx);

  }

  EVP_MD_CTX_init(ctx);

  return 1;

}

void EVP_MD_CTX_cleanse(EVP_MD_CTX *ctx) {

  OPENSSL_cleanse(ctx->md_data, ctx->digest->ctx_size);

  EVP_MD_CTX_cleanup(ctx);

}

void EVP_MD_CTX_free(EVP_MD_CTX *ctx) {

  if (!ctx) {

    return;

  }

  EVP_MD_CTX_cleanup(ctx);

  OPENSSL_free(ctx);

}

void EVP_MD_CTX_destroy(EVP_MD_CTX *ctx) { EVP_MD_CTX_free(ctx); }

int EVP_DigestFinalXOF(EVP_MD_CTX *ctx, uint8_t *out, size_t len) {

  OPENSSL_PUT_ERROR(DIGEST, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);

  return 0;

}

uint32_t EVP_MD_meth_get_flags(const EVP_MD *md) { return EVP_MD_flags(md); }

void EVP_MD_CTX_set_flags(EVP_MD_CTX *ctx, int flags) {}

int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out, const EVP_MD_CTX *in) {

  // |in->digest| may be NULL if this is a signing |EVP_MD_CTX| for, e.g.,

  // Ed25519 which does not hash with |EVP_MD_CTX|.

  if (in == NULL || (in->pctx == NULL && in->digest == NULL)) {

    OPENSSL_PUT_ERROR(DIGEST, DIGEST_R_INPUT_NOT_INITIALIZED);

    return 0;

  }

  EVP_PKEY_CTX *pctx = NULL;

  assert(in->pctx == NULL || in->pctx_ops != NULL);

  if (in->pctx) {

    pctx = in->pctx_ops->dup(in->pctx);

    if (!pctx) {

      return 0;

    }

  }

  uint8_t *tmp_buf = NULL;

  if (in->digest != NULL) {

    if (out->digest != in->digest) {

      assert(in->digest->ctx_size != 0);

      tmp_buf = OPENSSL_malloc(in->digest->ctx_size);

      if (tmp_buf == NULL) {

        if (pctx) {

          in->pctx_ops->free(pctx);

        }

        return 0;

      }

    } else {

      // |md_data| will be the correct size in this case. It's removed from

      // |out| so that |EVP_MD_CTX_cleanup| doesn't free it, and then it's

      // reused.

      tmp_buf = out->md_data;

      out->md_data = NULL;

    }

  }

  EVP_MD_CTX_cleanup(out);

  out->digest = in->digest;

  out->md_data = tmp_buf;

  if (in->digest != NULL) {

    OPENSSL_memcpy(out->md_data, in->md_data, in->digest->ctx_size);

  }

  out->pctx = pctx;

  out->pctx_ops = in->pctx_ops;

  assert(out->pctx == NULL || out->pctx_ops != NULL);

  return 1;

}

void EVP_MD_CTX_move(EVP_MD_CTX *out, EVP_MD_CTX *in) {

  EVP_MD_CTX_cleanup(out);

  // While not guaranteed, |EVP_MD_CTX| is currently safe to move with |memcpy|.

  // bssl-crypto currently relies on this, however, so if we change this, we

  // need to box the |HMAC_CTX|. (Relying on this is only fine because we assume

  // BoringSSL and bssl-crypto will always be updated atomically. We do not

  // allow any version skew between the two.)

  OPENSSL_memcpy(out, in, sizeof(EVP_MD_CTX));

  EVP_MD_CTX_init(in);

}

int EVP_MD_CTX_copy(EVP_MD_CTX *out, const EVP_MD_CTX *in) {

  EVP_MD_CTX_init(out);

  return EVP_MD_CTX_copy_ex(out, in);

}

int EVP_MD_CTX_reset(EVP_MD_CTX *ctx) {

  EVP_MD_CTX_cleanup(ctx);

  EVP_MD_CTX_init(ctx);

  return 1;

}

int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, ENGINE *engine) {

  if (ctx->digest != type) {

    assert(type->ctx_size != 0);

    uint8_t *md_data = OPENSSL_malloc(type->ctx_size);

    if (md_data == NULL) {

      return 0;

    }

    OPENSSL_free(ctx->md_data);

    ctx->md_data = md_data;

    ctx->digest = type;

  }

  assert(ctx->pctx == NULL || ctx->pctx_ops != NULL);

  ctx->digest->init(ctx);

  return 1;

}

int EVP_DigestInit(EVP_MD_CTX *ctx, const EVP_MD *type) {

  EVP_MD_CTX_init(ctx);

  return EVP_DigestInit_ex(ctx, type, NULL);

}

int EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *data, size_t len) {

  ctx->digest->update(ctx, data, len);

  return 1;

}

int EVP_DigestFinal_ex(EVP_MD_CTX *ctx, uint8_t *md_out, unsigned int *size) {

  assert(ctx->digest->md_size <= EVP_MAX_MD_SIZE);

  ctx->digest->final(ctx, md_out);

  if (size != NULL) {

    *size = ctx->digest->md_size;

  }

  OPENSSL_cleanse(ctx->md_data, ctx->digest->ctx_size);

  return 1;

}

int EVP_DigestFinal(EVP_MD_CTX *ctx, uint8_t *md, unsigned int *size) {

  (void)EVP_DigestFinal_ex(ctx, md, size);

  EVP_MD_CTX_cleanup(ctx);

  return 1;

}

int EVP_Digest(const void *data, size_t count, uint8_t *out_md,

               unsigned int *out_size, const EVP_MD *type, ENGINE *impl) {

  EVP_MD_CTX ctx;

  int ret;

  EVP_MD_CTX_init(&ctx);

  ret = EVP_DigestInit_ex(&ctx, type, impl) &&

        EVP_DigestUpdate(&ctx, data, count) &&

        EVP_DigestFinal_ex(&ctx, out_md, out_size);

  EVP_MD_CTX_cleanup(&ctx);

  return ret;

}

const EVP_MD *EVP_MD_CTX_md(const EVP_MD_CTX *ctx) {

  if (ctx == NULL) {

    return NULL;

  }

  return ctx->digest;

}

size_t EVP_MD_CTX_size(const EVP_MD_CTX *ctx) {

  return EVP_MD_size(EVP_MD_CTX_md(ctx));

}

size_t EVP_MD_CTX_block_size(const EVP_MD_CTX *ctx) {

  return EVP_MD_block_size(EVP_MD_CTX_md(ctx));

}

int EVP_MD_CTX_type(const EVP_MD_CTX *ctx) {

  return EVP_MD_type(EVP_MD_CTX_md(ctx));

}

int EVP_add_digest(const EVP_MD *digest) {

  return 1;

}