/* $OpenBSD: digest.c,v 1.34 2022/01/10 10:51:31 tb Exp $ */

/* 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.]

 */

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

 * Copyright (c) 1998-2001 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 <stdio.h>

#include <string.h>

#include <openssl/opensslconf.h>

#include <openssl/err.h>

#include <openssl/evp.h>

#include <openssl/objects.h>

#ifndef OPENSSL_NO_ENGINE

#include <openssl/engine.h>

#endif

#include "evp_locl.h"

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_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, ENGINE *impl)

{

  EVP_MD_CTX_clear_flags(ctx, EVP_MD_CTX_FLAG_CLEANED);

#ifndef OPENSSL_NO_ENGINE

  /* Whether it's nice or not, "Inits" can be used on "Final"'d contexts

   * so this context may already have an ENGINE! Try to avoid releasing

   * the previous handle, re-querying for an ENGINE, and having a

   * reinitialisation, when it may all be unecessary. */

  if (ctx->engine && ctx->digest && (!type ||

      (type && (type->type == ctx->digest->type))))

    goto skip_to_init;

  if (type) {

    /* Ensure an ENGINE left lying around from last time is cleared

     * (the previous check attempted to avoid this if the same

     * ENGINE and EVP_MD could be used). */

    ENGINE_finish(ctx->engine);

    if (impl != NULL) {

      if (!ENGINE_init(impl)) {

        EVPerror(EVP_R_INITIALIZATION_ERROR);

        return 0;

      }

    } else

      /* Ask if an ENGINE is reserved for this job */

      impl = ENGINE_get_digest_engine(type->type);

    if (impl != NULL) {

      /* There's an ENGINE for this job ... (apparently) */

      const EVP_MD *d = ENGINE_get_digest(impl, type->type);

      if (d == NULL) {

        /* Same comment from evp_enc.c */

        EVPerror(EVP_R_INITIALIZATION_ERROR);

        ENGINE_finish(impl);

        return 0;

      }

      /* We'll use the ENGINE's private digest definition */

      type = d;

      /* Store the ENGINE functional reference so we know

       * 'type' came from an ENGINE and we need to release

       * it when done. */

      ctx->engine = impl;

    } else

      ctx->engine = NULL;

  } else if (!ctx->digest) {

    EVPerror(EVP_R_NO_DIGEST_SET);

    return 0;

  }

#endif

  if (ctx->digest != type) {

    if (ctx->digest && ctx->digest->ctx_size && ctx->md_data &&

        !EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_REUSE)) {

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

      ctx->md_data = NULL;

    }

    ctx->digest = type;

    if (!(ctx->flags & EVP_MD_CTX_FLAG_NO_INIT) && type->ctx_size) {

      ctx->update = type->update;

      ctx->md_data = calloc(1, type->ctx_size);

      if (ctx->md_data == NULL) {

        EVP_PKEY_CTX_free(ctx->pctx);

        ctx->pctx = NULL;

        EVPerror(ERR_R_MALLOC_FAILURE);

        return 0;

      }

    }

  }

#ifndef OPENSSL_NO_ENGINE

skip_to_init:

#endif

  if (ctx->pctx) {

    int r;

    r = EVP_PKEY_CTX_ctrl(ctx->pctx, -1, EVP_PKEY_OP_TYPE_SIG,

        EVP_PKEY_CTRL_DIGESTINIT, 0, ctx);

    if (r <= 0 && (r != -2))

      return 0;

  }

  if (ctx->flags & EVP_MD_CTX_FLAG_NO_INIT)

    return 1;

  return ctx->digest->init(ctx);

}

int

EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *data, size_t count)

{

  return ctx->update(ctx, data, count);

}

/* The caller can assume that this removes any secret data from the context */

int

EVP_DigestFinal(EVP_MD_CTX *ctx, unsigned char *md, unsigned int *size)

{

  int ret;

  ret = EVP_DigestFinal_ex(ctx, md, size);

  EVP_MD_CTX_cleanup(ctx);

  return ret;

}

/* The caller can assume that this removes any secret data from the context */

int

EVP_DigestFinal_ex(EVP_MD_CTX *ctx, unsigned char *md, unsigned int *size)

{

  int ret;

  if ((size_t)ctx->digest->md_size > EVP_MAX_MD_SIZE) {

    EVPerror(EVP_R_TOO_LARGE);

    return 0;

  }

  ret = ctx->digest->final(ctx, md);

  if (size != NULL)

    *size = ctx->digest->md_size;

  if (ctx->digest->cleanup) {

    ctx->digest->cleanup(ctx);

    EVP_MD_CTX_set_flags(ctx, EVP_MD_CTX_FLAG_CLEANED);

  }

  memset(ctx->md_data, 0, ctx->digest->ctx_size);

  return ret;

}

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_copy_ex(EVP_MD_CTX *out, const EVP_MD_CTX *in)

{

  unsigned char *tmp_buf;

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

    EVPerror(EVP_R_INPUT_NOT_INITIALIZED);

    return 0;

  }

#ifndef OPENSSL_NO_ENGINE

  /* Make sure it's safe to copy a digest context using an ENGINE */

  if (in->engine && !ENGINE_init(in->engine)) {

    EVPerror(ERR_R_ENGINE_LIB);

    return 0;

  }

#endif

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

    tmp_buf = out->md_data;

    EVP_MD_CTX_set_flags(out, EVP_MD_CTX_FLAG_REUSE);

  } else

    tmp_buf = NULL;

  EVP_MD_CTX_cleanup(out);

  memcpy(out, in, sizeof *out);

  out->md_data = NULL;

  out->pctx = NULL;

  /*

   * Because of the EVP_PKEY_CTX_dup() below, EVP_MD_CTX_cleanup() needs

   * to free out->pctx in all cases (even if this flag is set on in).

   */

  EVP_MD_CTX_clear_flags(out, EVP_MD_CTX_FLAG_KEEP_PKEY_CTX);

  if (in->md_data && out->digest->ctx_size) {

    if (tmp_buf) {

      out->md_data = tmp_buf;

    } else {

      out->md_data = calloc(1, out->digest->ctx_size);

      if (out->md_data == NULL) {

        EVPerror(ERR_R_MALLOC_FAILURE);

        return 0;

      }

    }

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

  }

  out->update = in->update;

  if (in->pctx) {

    out->pctx = EVP_PKEY_CTX_dup(in->pctx);

    if (!out->pctx) {

      EVP_MD_CTX_cleanup(out);

      return 0;

    }

  }

  if (out->digest->copy)

    return out->digest->copy(out, in);

  return 1;

}

int

EVP_Digest(const void *data, size_t count,

    unsigned char *md, unsigned int *size, const EVP_MD *type, ENGINE *impl)

{

  EVP_MD_CTX ctx;

  int ret;

  EVP_MD_CTX_init(&ctx);

  EVP_MD_CTX_set_flags(&ctx, EVP_MD_CTX_FLAG_ONESHOT);

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

      EVP_DigestUpdate(&ctx, data, count) &&

      EVP_DigestFinal_ex(&ctx, md, size);

  EVP_MD_CTX_cleanup(&ctx);

  return ret;

}

EVP_MD_CTX *

EVP_MD_CTX_new(void)

{

  return calloc(1, sizeof(EVP_MD_CTX));

}

void

EVP_MD_CTX_free(EVP_MD_CTX *ctx)

{

  if (ctx == NULL)

    return;

  EVP_MD_CTX_cleanup(ctx);

  free(ctx);

}

void

EVP_MD_CTX_init(EVP_MD_CTX *ctx)

{

  memset(ctx, 0, sizeof(*ctx));

}

int

EVP_MD_CTX_reset(EVP_MD_CTX *ctx)

{

  return EVP_MD_CTX_cleanup(ctx);

}

EVP_MD_CTX *

EVP_MD_CTX_create(void)

{

  return EVP_MD_CTX_new();

}

void

EVP_MD_CTX_destroy(EVP_MD_CTX *ctx)

{

  EVP_MD_CTX_free(ctx);

}

/* This call frees resources associated with the context */

int

EVP_MD_CTX_cleanup(EVP_MD_CTX *ctx)

{

  /*

   * Don't assume ctx->md_data was cleaned in EVP_Digest_Final,

   * because sometimes only copies of the context are ever finalised.

   */

  if (ctx->digest && ctx->digest->cleanup &&

      !EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_CLEANED))

    ctx->digest->cleanup(ctx);

  if (ctx->digest && ctx->digest->ctx_size && ctx->md_data &&

      !EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_REUSE))

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

  /*

   * If EVP_MD_CTX_FLAG_KEEP_PKEY_CTX is set, EVP_MD_CTX_set_pkey() was

   * called and its strange API contract implies we don't own ctx->pctx.

   */

  if (!EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_KEEP_PKEY_CTX))

    EVP_PKEY_CTX_free(ctx->pctx);

#ifndef OPENSSL_NO_ENGINE

  ENGINE_finish(ctx->engine);

#endif

  memset(ctx, 0, sizeof(*ctx));

  return 1;

}

int

EVP_MD_CTX_ctrl(EVP_MD_CTX *ctx, int type, int arg, void *ptr)

{

  int ret;

  if (!ctx->digest) {

    EVPerror(EVP_R_NO_CIPHER_SET);

    return 0;

  }

  if (!ctx->digest->md_ctrl) {

    EVPerror(EVP_R_CTRL_NOT_IMPLEMENTED);

    return 0;

  }

  ret = ctx->digest->md_ctrl(ctx, type, arg, ptr);

  if (ret == -1) {

    EVPerror(EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED);

    return 0;

  }

  return ret;

}