// Copyright (c) 2004-2009 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:

//

/**

 @file ramod.cpp

 @internalComponent

*/

#include <in_chk.h>

#include <icmp6_hdr.h>

#include <in_sock.h>

#include <in_bind.h>

#include "in6_opt.h"

#include "ramod.h"

#include "HookLog.h"

Cramod* Cramod::NewL()

	{

	Cramod* self = new(ELeave) Cramod();

	CleanupStack::PushL(self);

	self->ConstructL();

	CleanupStack::Pop();

	return self;

	}

void Cramod::ConstructL()

	{

	}

Cramod::Cramod()

	{

	}

Cramod::~Cramod()

	{

	}

void Cramod::BindL(CProtocolBase* aProtocol, TUint aId)

	{

	// Do sanity checks

	//

	if ((aId != KProtocolInet6Ip) || (aProtocol == this))

		{

		User::Leave(KErrArgument);

		}

	TUint ourId;

		{

		TServerProtocolDesc info;

		Identify(&info);

		ourId = info.iProtocol;

		}

	if (aId == ourId)

		{

		User::Leave(KErrArgument);

		}

	if ( iProtocolIPv6 != NULL )

		{

		if ( iProtocolIPv6 == aProtocol )

			{

			// We don't need to bind to the same protocol twice.

			//

			return;

			}

		else

			{

			// We don't want to bind to a different protocol either...

			//

			User::Leave(KErrAlreadyExists);

			}

		}

	iProtocolIPv6 = (CProtocolInet6Binder*) aProtocol;

	RegisterHooksL();

	}

void Cramod::Unbind(CProtocolBase* aProtocol, TUint /* aId */)

	{

	if (iProtocolIPv6 != aProtocol)

		{

		return;

		}

	UnregisterHooks();

	iProtocolIPv6 = 0;

	}

void Cramod::RegisterHooksL(void)

/**

 * Registers the hook to catch IP stack events

 */

	{

	if(!iProtocolIPv6)

		{

		User::Leave(KErrNotReady);

		}

	// bind to IP for incoming packets

	iProtocolIPv6->BindL((CProtocolBase*)this, BindHookFor(KProtocolInet6Icmp));

	}

void Cramod::UnregisterHooks(void)

/**

 * Detaches this hook from the running of the stack.

 *  This is so IPEN doesn't slow down the stack while it isn't

 *   needed by any clients.

 *

 *  e.g. without this mechanism, every incoming packet would pass through

 *   Cramod::ApplyL pointlessly.

 *

 */

	{

	if(!iProtocolIPv6)

		{

		return;

		}

	// If IPv6 exists, unbind the hook. Covers both in/out hooks (I hope)

	iProtocolIPv6->Unbind(this);

	}

void Cramod::FillIdentification(TServerProtocolDesc& anEntry)

/**

 * Fills in an existing protocol description structure with details of this protocol.

 *

 * @param aProtocolDesc: reference to the structure to be filled in

 */

	{

	anEntry.iName=_S("ramod");

	anEntry.iAddrFamily=KAfInet; //KAfExain;

	anEntry.iSockType=KSockDatagram;

	anEntry.iProtocol=KMyProtocolId;

	anEntry.iVersion=TVersion(1, 0, 0);

	anEntry.iByteOrder=EBigEndian;

	anEntry.iServiceInfo=KSIDatagram | KSIConnectionLess;

	anEntry.iNamingServices=0;

	anEntry.iSecurity=KSocketNoSecurity;

	anEntry.iMessageSize=0xffff;

	anEntry.iServiceTypeInfo=0; // 1 for ability to create sockets

	anEntry.iNumSockets=KUnlimitedSockets;

	}

void Cramod::Identify(TServerProtocolDesc* aProtocolDesc) const

/**

 * Fills in an existing protocol description structure with details of this protocol.

 *

 * @param aProtocolDesc: pointer to the structure to be filled in

 */

	{

	FillIdentification(*aProtocolDesc);

	}

/**

 * Incoming packet

 */

TInt Cramod::ApplyL(RMBufHookPacket& aPacket, RMBufRecvInfo& aInfo)

	{

	LOG	(

		_LIT(KHookNotifyStr,"Cramod::ApplyL hit with protocol: %d");

		HookLog::Printf( KHookNotifyStr , aInfo.iProtocol );

		)

	if(aInfo.iProtocol == static_cast<TInt>(KProtocolInet6Icmp))

		{

		LOG	(

			_LIT(KHookNotifyStr," ICMPv6 packet detected");

			HookLog::Printf( KHookNotifyStr );

			)

		/**

		 * Could switch on ICMP type here, in case the hook needs to catch

		 *   other ICMP packet types..

		 */

		TInet6Checksum<TInet6HeaderICMP_RouterAdv> icmp(aPacket,aInfo.iOffset);

		if(icmp.iHdr)

			{

			if (icmp.iHdr->Type() == KInet6ICMP_RouterAdv &&

				icmp.VerifyChecksum( aPacket,

							  aInfo.iProtocol == static_cast<TInt>(KProtocolInet6Icmp) ? &aInfo : NULL,

							  aInfo.iOffset) )

				{

#ifdef RAMOD1

				// RA received from LAN, modfiy the M and O flag here, clear 'M' flag and set 'O' flag

				icmp.iHdr->SetFlags(64);

				icmp.ComputeChecksum( aPacket,

							aInfo.iProtocol == static_cast<TInt> (KProtocolInet6Icmp) ? &aInfo : NULL,

							aInfo.iOffset );

#elif RAMOD2

				// RA received from LAN, modfiy the M and O flag here, set both 'M' and 'O' flags as false

				icmp.iHdr->SetFlags(0);

				icmp.ComputeChecksum( aPacket,

							aInfo.iProtocol == static_cast<TInt> (KProtocolInet6Icmp) ? &aInfo : NULL,

							aInfo.iOffset );

#elif RAMOD3

				// RA received, modfiy the M and O flag here, invalidate checksum by changing flag, Don't compute checksum, packets will be dropped

				icmp.iHdr->SetFlags(0);

#endif

				}

			}

		}

	return KIp6Hook_PASS;   // ensure we don't affect the control flow

	}