/*

* Copyright (c) 2006-2007 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "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:   

*

*/

#include "natfwunsaffingerprintattribute.h"

#include "natfwunsafmessage.h"

#include "natfwunsafutils.h"

#include "natfwunsaflog.h"

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::DecodeL

// -----------------------------------------------------------------------------

//

CNATFWUNSAFFingerprintAttribute*

CNATFWUNSAFFingerprintAttribute::DecodeL(const TDesC8& aValue)

    {

    CNATFWUNSAFFingerprintAttribute* self =

        new (ELeave) CNATFWUNSAFFingerprintAttribute();

    CleanupStack::PushL(self);

    self->DecodeValueL(aValue);

    CleanupStack::Pop(self);

    return self;

    }

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::NewL

// -----------------------------------------------------------------------------

//

CNATFWUNSAFFingerprintAttribute*

CNATFWUNSAFFingerprintAttribute::NewL(CBufBase& aNATFWUNSAFMessage)

    {

    CNATFWUNSAFFingerprintAttribute* self =

        CNATFWUNSAFFingerprintAttribute::NewLC(aNATFWUNSAFMessage);

    CleanupStack::Pop(self);

    return self;

    }

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::NewLC

// -----------------------------------------------------------------------------

//

CNATFWUNSAFFingerprintAttribute*

CNATFWUNSAFFingerprintAttribute::NewLC(CBufBase& aNATFWUNSAFMessage)

    {

    CNATFWUNSAFFingerprintAttribute* self =

        new (ELeave) CNATFWUNSAFFingerprintAttribute();

    CleanupStack::PushL(self);

    self->ConstructL(aNATFWUNSAFMessage);

    return self;

    }

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::DecodeAttributeL

// -----------------------------------------------------------------------------

//

CNATFWUNSAFAttribute*

CNATFWUNSAFFingerprintAttribute::DecodeAttributeL(

    const TDesC8& aByteStream)

    {

    CheckLengthL(aByteStream);

    return DecodeL(aByteStream.Mid(EValueOffset));

    }

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::CNATFWUNSAFFingerprintAttribute

// -----------------------------------------------------------------------------

//

CNATFWUNSAFFingerprintAttribute::CNATFWUNSAFFingerprintAttribute()

    {

    }

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::ConstructL

// Update message header's length field to include the FINGERPRINT before

// computing the CRC-32.

// -----------------------------------------------------------------------------

//

void CNATFWUNSAFFingerprintAttribute::ConstructL(CBufBase& aNATFWUNSAFMessage)

    {

    __ASSERT_ALWAYS(aNATFWUNSAFMessage.Size(), User::Leave(KErrArgument));

    TInt length = CNATFWUNSAFMessage::MessageLength(aNATFWUNSAFMessage.Ptr(0));

    CNATFWUNSAFMessage::SetMessageLength(aNATFWUNSAFMessage,

        length + EValueOffset + EAttributeValueSize);

    ComputeCRC32(aNATFWUNSAFMessage, iCRC);

    }

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::~CNATFWUNSAFFingerprintAttribute

// -----------------------------------------------------------------------------

//

CNATFWUNSAFFingerprintAttribute::~CNATFWUNSAFFingerprintAttribute()

    {

    }

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::Type

// -----------------------------------------------------------------------------

//

CNATFWUNSAFAttribute::TType CNATFWUNSAFFingerprintAttribute::Type() const

    {

    return EFingerprint;

    }

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::EncodeValueL

// -----------------------------------------------------------------------------

//

HBufC8* CNATFWUNSAFFingerprintAttribute::EncodeValueL() const

    {

    HBufC8* encodedValue = HBufC8::NewLC(EAttributeValueSize);

    TPtr8 ptr = encodedValue->Des();

    ptr.FillZ(EAttributeValueSize);

    TUint32 value(iCRC);

    NATFWUNSAFUtils::WriteNetworkOrder32L(ptr, 0, value);

    CleanupStack::Pop(encodedValue);

    return encodedValue;

    }

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::CheckLengthL

// This attribute has a fixed length

// -----------------------------------------------------------------------------

//

void CNATFWUNSAFFingerprintAttribute::CheckLengthL(

    const TDesC8& aByteStream)

    {

    __ASSERT_ALWAYS(ParseLengthL(aByteStream) == EAttributeValueSize,

                    User::Leave(KErrCorrupt));

    }

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::CheckFingerprintL

// Exclude FINGERPRINT attribute from CRC-32 computing. It is located at the

// end of the message.

// -----------------------------------------------------------------------------

//

EXPORT_C TBool CNATFWUNSAFFingerprintAttribute::CheckFingerprintL(

    const TDesC8& aNATFWUNSAFMessage) const

    {

    TInt KFingerprintSize = static_cast<TInt>(EValueOffset) +

        static_cast<TInt>(EAttributeValueSize);

    //Check there is enough data

    __ASSERT_ALWAYS(aNATFWUNSAFMessage.Length() >= KFingerprintSize,

                    User::Leave(KErrArgument));

    CBufBase* message = CBufFlat::NewL(

        aNATFWUNSAFMessage.Length() - KFingerprintSize);

    CleanupStack::PushL(message);

    message->InsertL(0,

                     aNATFWUNSAFMessage,

                     aNATFWUNSAFMessage.Length() - KFingerprintSize);

    TUint32 crc(0);

    ComputeCRC32(*message, crc);

    TBool match = (crc == iCRC);

    NATFWUNSAF_INTLOG("Checking FINGERPRINT, match", match)

    CleanupStack::PopAndDestroy(message);

    return match;

    }

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::DecodeValueL

// -----------------------------------------------------------------------------

//

void CNATFWUNSAFFingerprintAttribute::DecodeValueL(const TDesC8& aValue)

    {

    __ASSERT_ALWAYS(aValue.Length() == EAttributeValueSize,

        User::Leave(KErrCorrupt));

    iCRC = BigEndian::Get32(aValue.Ptr());

    }

// -----------------------------------------------------------------------------

// CNATFWUNSAFFingerprintAttribute::ComputeCRC32

// -----------------------------------------------------------------------------

//

void CNATFWUNSAFFingerprintAttribute::ComputeCRC32(

    CBufBase& aNATFWUNSAFMessage,

    TUint32& aCRC) const

    {

    // Perform the CCITT CRC-32 checksum on the message

    Mem::Crc32(aCRC, aNATFWUNSAFMessage.Ptr(0).Ptr(),

        sizeof(aNATFWUNSAFMessage));

    // XOR according to RFC3489-bis05

    aCRC ^= EXORedValue;

    }