/*

* Copyright (c) 2005-2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

*

*/

/**

 @file

 @publishedPartner

 @released

*/

#ifndef __PKCS7_DIGEST_INFO_H__

#define __PKCS7_DIGEST_INFO_H__

#include <e32base.h>

#include <x509cert.h>

#include <signed.h>

#include <asn1dec.h>

/**

 Provides the means to decode PKCS#7 encoded DigestInfo Structure.

 */

class CPKCS7DigestInfo : public CBase

	{

public:	

	/**

	 Creates a new PKCS#7 DigestInfo object. 

	 @param     aRawData contains a PKCS#7 DigestInfo Structure

	 @return    A pointer to the newly allocated object.

	 @leave 	KErrArgument if digestAlgorithm and digest is not present.

	 @leave 	KErrNotSupported if algorithm is other than MD2, MD5 and SHA1.

	 */

    IMPORT_C static CPKCS7DigestInfo* NewL(const TDesC8& aRawData);

    /**

	 An Algorithm present DigestAlgorithmIdentifier.

     @return    The enum which identifies the type of Algorithm

                used to obtain the hash.

     */   

	IMPORT_C TAlgorithmId Algorithm() const;

	/**

	 Encoded Parameters present in the DigestAlgorithmIdentifier.

	 The client has to check for data length. It is 0 in case there are no EncodedParams

	 @return    The Encoded Parameters which is in the DigestAlgorithmIdentifier.

     */     

	IMPORT_C const TPtrC8& EncodedParams() const;

	/**

	 The Digest which is in the DigestInfo.

	 @return    The Digest which is in the DigestInfo and is an Octet String.

     */

	IMPORT_C const TDesC8& Digest() const;

	/**

	 Destructor.

	 */

	virtual ~CPKCS7DigestInfo();

private:

	/**

	 Constructor.

	 */

    CPKCS7DigestInfo(); 

    /**

	 Copy Constructor.

	 @param aDigestInfo A CPKCS7DigestInfo object.

	 */

	CPKCS7DigestInfo(const CPKCS7DigestInfo& aDigestInfo);

	/**

	 Assignment operator.

	 @param aDigestInfo A CPKCS7DigestInfo object.

	 @return A reference to CPKCS7DigestInfo class.

	 */

	CPKCS7DigestInfo& operator=(const CPKCS7DigestInfo& aDigestInfo);

	/**

	 Decodes the given ASN1 DigestInfo. Below is the ASN1 syntax

	 DigestInfo ::= SEQUENCE

	 	{

	    digestAlgorithm  DigestAlgorithmIdentifier,

	    digest           Digest

	    }

	 Digest ::= OCTET String	 

	 DigestAlgorithmIdentifier ::= AlgorithmIdentifier

	 AlgorithmIdentifier ::= SEQUENCE 

	 	{

	    algorithm   ALGORITHM.&id({SupportedAlgorithms}),

	    parameters  ALGORITHM.&Type({SupportedAlgorithms}{@ algorithm}) OPTIONAL

	    }

	 @param     aRawData A descriptor containing the PKCS7 DigestInfo Sequence.

	 @leave KErrArgument if digestAlgorithm and digest is not present.

	 @leave KErrNotSupported if algorithm is other than MD2, MD5 and SHA1.

	 @see TASN1DecGeneric, CX509AlgorithmIdentifier.

	 */

    void ConstructL(const TDesC8& aRawData);

private:

    /** 

     The object identifier which identifies the message-digest algorithm.

	 A message-digest algorithm maps an octet string (the message) to 

	 another octet string (the message digest) 

	 */

	TAlgorithmId iAlgorithmId;

	/** Encoded Parameters which is in the DigestAlgorithmIdentifier */

    TPtrC8 iEncodedParams;

	/** 

	 The Digest is present in the DigestInfo. 

	 It is the result of the message-digesting process 

	 */

	TPtrC8 iDigest;

	};

#endif //__PKCS7_DIGEST_INFO_H__