/* crypto/evp/digest.c */

/* 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 "cryptlib.h"

#include <openssl/objects.h>

#include <openssl/evp.h>

#ifndef OPENSSL_NO_ENGINE

#include <openssl/engine.h>

#endif

EXPORT_C void EVP_MD_CTX_init(EVP_MD_CTX *ctx)

	{

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

	}

EXPORT_C EVP_MD_CTX *EVP_MD_CTX_create(void)

	{

	EVP_MD_CTX *ctx=OPENSSL_malloc(sizeof *ctx);

    if(ctx==NULL)

	{

	   return ctx;

	}

	EVP_MD_CTX_init(ctx);

	return ctx;

	}

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

	{

	EVP_MD_CTX_init(ctx);

	return EVP_DigestInit_ex(ctx, type, NULL);

	}

EXPORT_C 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). */

		if(ctx->engine)

			ENGINE_finish(ctx->engine);

		if(impl)

			{

			if (!ENGINE_init(impl))

				{

				EVPerr(EVP_F_EVP_DIGESTINIT_EX,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)

			{

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

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

			if(!d)

				{

				/* Same comment from evp_enc.c */

				EVPerr(EVP_F_EVP_DIGESTINIT_EX,EVP_R_INITIALIZATION_ERROR);

				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)

		{

		EVPerr(EVP_F_EVP_DIGESTINIT_EX,EVP_R_NO_DIGEST_SET);

		return 0;

		}

#endif

	if (ctx->digest != type)

		{

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

		  { if(ctx->md_data)

			  OPENSSL_free(ctx->md_data);

		  }

		ctx->digest=type;

		if (type->ctx_size)

		{

			ctx->md_data=OPENSSL_malloc(type->ctx_size);

			if(ctx->md_data==NULL)

			{

			    EVPerr(EVP_F_EVP_DIGESTINIT_EX,ERR_R_MALLOC_FAILURE);

			    return 0;

			}

		}

		}

#ifndef OPENSSL_NO_ENGINE

skip_to_init:

#endif

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

	}

EXPORT_C int EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *data,

	     size_t count)

	{

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

	}

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

EXPORT_C 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 */

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

	{

	int ret;

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

	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);

		}

	if(ctx->md_data)	

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

	return ret;

	}

EXPORT_C 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);

	}

EXPORT_C 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))

		{

		EVPerr(EVP_F_EVP_MD_CTX_COPY_EX,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))

		{

		EVPerr(EVP_F_EVP_MD_CTX_COPY_EX,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);

	if (out->digest->ctx_size)

		{

		 if (tmp_buf) out->md_data = tmp_buf;

		 else out->md_data=OPENSSL_malloc(out->digest->ctx_size);

     if(out->md_data==NULL||in->md_data==NULL)

        {

           EVPerr(EVP_F_EVP_MD_CTX_COPY_EX,ERR_R_MALLOC_FAILURE);

		       return 0;

        } 

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

		}

	if (out->digest->copy)

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

	return 1;

	}

EXPORT_C 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;

	}

EXPORT_C void EVP_MD_CTX_destroy(EVP_MD_CTX *ctx)

	{

	EVP_MD_CTX_cleanup(ctx);

	OPENSSL_free(ctx);

	}

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

EXPORT_C 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))

		{

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

		OPENSSL_free(ctx->md_data);

		}

#ifndef OPENSSL_NO_ENGINE

	if(ctx->engine)

		/* The EVP_MD we used belongs to an ENGINE, release the

		 * functional reference we held for this reason. */

		ENGINE_finish(ctx->engine);

#endif

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

	return 1;

	}