/* crypto/asn1/a_verify.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.]

 */

#include <stdio.h>

#include <time.h>

#include "cryptlib.h"

#ifndef NO_SYS_TYPES_H

# include <sys/types.h>

#endif

#include <openssl/bn.h>

#include <openssl/x509.h>

#include <openssl/objects.h>

#include <openssl/buffer.h>

#include <openssl/evp.h>

#ifndef NO_ASN1_OLD

EXPORT_C int ASN1_verify(i2d_of_void *i2d, X509_ALGOR *a, ASN1_BIT_STRING *signature,

		char *data, EVP_PKEY *pkey)

	{

	EVP_MD_CTX ctx;

	const EVP_MD *type;

	unsigned char *p,*buf_in=NULL;

	int ret= -1,i,inl;

	EVP_MD_CTX_init(&ctx);

	i=OBJ_obj2nid(a->algorithm);

	type=EVP_get_digestbyname(OBJ_nid2sn(i));

	if (type == NULL)

		{

		ASN1err(ASN1_F_ASN1_VERIFY,ASN1_R_UNKNOWN_MESSAGE_DIGEST_ALGORITHM);

		goto err;

		}

	inl=i2d(data,NULL);

	buf_in=OPENSSL_malloc((unsigned int)inl);

	if (buf_in == NULL)

		{

		ASN1err(ASN1_F_ASN1_VERIFY,ERR_R_MALLOC_FAILURE);

		goto err;

		}

	p=buf_in;

	i2d(data,&p);

	EVP_VerifyInit_ex(&ctx,type, NULL);

	EVP_VerifyUpdate(&ctx,(unsigned char *)buf_in,inl);

	OPENSSL_cleanse(buf_in,(unsigned int)inl);

	OPENSSL_free(buf_in);

	if (EVP_VerifyFinal(&ctx,(unsigned char *)signature->data,

			(unsigned int)signature->length,pkey) <= 0)

		{

		ASN1err(ASN1_F_ASN1_VERIFY,ERR_R_EVP_LIB);

		ret=0;

		goto err;

		}

	/* we don't need to zero the 'ctx' because we just checked

	 * public information */

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

	ret=1;

err:

	EVP_MD_CTX_cleanup(&ctx);

	return(ret);

	}

#endif

EXPORT_C int ASN1_item_verify(const ASN1_ITEM *it, X509_ALGOR *a, ASN1_BIT_STRING *signature,

	     void *asn, EVP_PKEY *pkey)

	{

	EVP_MD_CTX ctx;

	const EVP_MD *type;

	unsigned char *buf_in=NULL;

	int ret= -1,i,inl;

	EVP_MD_CTX_init(&ctx);

	i=OBJ_obj2nid(a->algorithm);

	type=EVP_get_digestbyname(OBJ_nid2sn(i));

	if (type == NULL)

		{

		ASN1err(ASN1_F_ASN1_ITEM_VERIFY,ASN1_R_UNKNOWN_MESSAGE_DIGEST_ALGORITHM);

		goto err;

		}

	if (!EVP_VerifyInit_ex(&ctx,type, NULL))

		{

		ASN1err(ASN1_F_ASN1_ITEM_VERIFY,ERR_R_EVP_LIB);

		ret=0;

		goto err;

		}

	inl = ASN1_item_i2d(asn, &buf_in, it);

	if (buf_in == NULL)

		{

		ASN1err(ASN1_F_ASN1_ITEM_VERIFY,ERR_R_MALLOC_FAILURE);

		goto err;

		}

	EVP_VerifyUpdate(&ctx,(unsigned char *)buf_in,inl);

	OPENSSL_cleanse(buf_in,(unsigned int)inl);

	OPENSSL_free(buf_in);

	if (EVP_VerifyFinal(&ctx,(unsigned char *)signature->data,

			(unsigned int)signature->length,pkey) <= 0)

		{

		ASN1err(ASN1_F_ASN1_ITEM_VERIFY,ERR_R_EVP_LIB);

		ret=0;

		goto err;

		}

	/* we don't need to zero the 'ctx' because we just checked

	 * public information */

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

	ret=1;

err:

	EVP_MD_CTX_cleanup(&ctx);

	return(ret);

	}