/*

* 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 <es_sock.h>

#include "natfwunsafattribute.h"

#include "natfwunsafutils.h"

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

// CNATFWUNSAFAttribute::CNATFWUNSAFAttribute

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

//

CNATFWUNSAFAttribute::CNATFWUNSAFAttribute()

    {

    }

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

// CNATFWUNSAFAttribute::~CNATFWUNSAFAttribute

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

//

CNATFWUNSAFAttribute::~CNATFWUNSAFAttribute()

    {

    }

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

// CNATFWUNSAFAttribute::EncodeL

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

//

HBufC8* CNATFWUNSAFAttribute::EncodeL() const

    {

    HBufC8* value = EncodeValueL();

    CleanupStack::PushL(value);

    TInt attrValLength = value->Length();

    //Pad non-DWORD-boundary aligned attributes with spaces if needed. Spaces

    //used instead of \0 in order to not mess up buggy C implementations.

    const TInt KGranularity = 4;

    TInt bytesInLastBlock = attrValLength % KGranularity;

    TInt bytesToAppend = KGranularity - bytesInLastBlock;

    if (0 < bytesInLastBlock && !IsWordBoundaryAligned(Type()))

        {

        CBufBase* valueBuf = CBufFlat::NewL(attrValLength + bytesToAppend);

        CleanupStack::PushL(valueBuf);

        valueBuf->InsertL(0, *value, attrValLength);

        const TChar KSpace(' ');

        for (TInt i = 0; i < bytesToAppend; ++i)

            {

            valueBuf->InsertL(valueBuf->Size(), &KSpace, 1);

            }

        // Store value pointer for proper cleanupstack handling

        HBufC8* oldValue = value;

        value = valueBuf->Ptr(0).AllocL();

        CleanupStack::PopAndDestroy(valueBuf);

        CleanupStack::PopAndDestroy( oldValue );

        CleanupStack::PushL( value );

        }

    HBufC8* attribute = HBufC8::NewLC(value->Length() + EValueOffset);

    TPtr8 ptr = attribute->Des();

    ptr.FillZ(EValueOffset);

    NATFWUNSAFUtils::WriteNetworkOrder16L(ptr, ETypeOffset, Type());

    NATFWUNSAFUtils::WriteNetworkOrder16L(ptr,

                                     ELengthOffset,

                                     static_cast<TUint16>(attrValLength));

    ptr.Append(*value);

    CleanupStack::Pop(attribute);

    CleanupStack::PopAndDestroy(value);

    return attribute;

    }

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

// CNATFWUNSAFAttribute::ParseLengthL

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

//

TUint16 CNATFWUNSAFAttribute::ParseLengthL(const TDesC8& aByteStream)

    {

    __ASSERT_ALWAYS(aByteStream.Length() >= EValueOffset,

                    User::Leave(KErrArgument));

    return BigEndian::Get16(aByteStream.Mid(ELengthOffset).Ptr());

    }

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

// CNATFWUNSAFAttribute::ParseTypeAndLengthL

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

//

void CNATFWUNSAFAttribute::ParseTypeAndLengthL(const TDesC8& aByteStream,

                                           TUint16& aType,

                                           TUint16& aTotalLength)

    {

    //Stream must have enough data to contain at least an attribute with

    //zero-length value

    __ASSERT_ALWAYS(aByteStream.Length() >= EValueOffset,

                    User::Leave(KErrArgument));

    TUint16 totalLength = ParseLengthL(aByteStream) + EValueOffset;

    //Increase total length if it's not a multiple of 4 bytes.

    //This is because of possible padding in text attributes not visible from

    //attribute length field.

    const TUint16 KGranularity = 4;

    TUint16 bytesInLastBlock = totalLength % KGranularity;

    TUint16 bytesPadded = KGranularity - bytesInLastBlock;

    if (0 < bytesInLastBlock )

        {

        totalLength += bytesPadded;

        }

    __ASSERT_ALWAYS(aByteStream.Length() >= totalLength,

                    User::Leave(KErrArgument));

    aTotalLength = totalLength;

    aType = BigEndian::Get16(aByteStream.Mid(ETypeOffset).Ptr());

    }

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

// CNATFWUNSAFAttribute::IsMandatory

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

//

TBool CNATFWUNSAFAttribute::IsMandatory(TUint16 aType)

    {

    const TInt KLargestMandatoryValue = 0x7fff; //RFC 3489

    return aType <= KLargestMandatoryValue;

    }

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

// CNATFWUNSAFAttribute::IsWordBoundaryAligned

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

//

TBool CNATFWUNSAFAttribute::IsWordBoundaryAligned(TUint16 aType)

    {

    return !(aType == EUsername ||

             aType == EPassword ||

             aType == EData     ||

             aType == EServer   ||

             aType == ENonce    ||

             aType == ERealm    ||

             aType == EErrorCode);

    }