// 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 "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:

// llmnrconflict.h - Interface definitions LLMNR name conflict notification

// Interface definitions for the LLMNR name conflict notification

//

/**

 @file llmnrconflict.h

 @publishedPartner

 @released

*/

#ifndef __LLMNRCONFLICT_H__

#define __LLMNRCONFLICT_H__

#include <es_sock.h>

/**

* The notification UID

*/

TInt KLlmnrConflictNotifyUid = 0x101F6D23;

class TLlmnrConflictName

	{

public:

	inline TBool IsSafe() const;

	THostName	iName;				//< The host name.

	};

class TLlmnrConflictNotify : public TLlmnrConflictName

	/**

	* Conflict notification message format.

	*

	* The base iName contains the link local name which is conflict

	* with some other host on some interface assotiated with the

	* indicated IAP (iIAPId).

	*/

	{

public:

	TUint32		iIAPId;				//< ID of selected IAP

	TUint32		iNetworkId;			//< ID of Network to which IAP belongs

	};

/**

* The reply from notifier only has the replacement host name.

*

* The the nofitier completes with KErrNone, the reply message can contain

* a the new name. If this new name is also colliding with someone, another

* notify is issued.

*

* If the notifier does not want LLMNR to try an alternate name, it should

* either complete with some error (KErrCancel for example), or KErrNone

* with empty replacement name (iName.Length() == 0).

*/

typedef TLlmnrConflictName TLlmnrConflictReply;

TBool TLlmnrConflictName::IsSafe() const

	/**

	* Test if iName really is a TBuf derived descriptor.

	*/

	{

	// This test is defined, because this structure is passed as a parameter,

	// and any sender of the message can crash the receiver by placing tailored "garbage"

	// on TBuf descriptor. The receiver has no official way of validating that TBuf

	// descriptor is correct, and the garbage can be such that any reference to the

	// content of TBuf will cause panic (for example place into iTypeLength field a

	// value that implies TPtr and NULL into actual buffer address).

	//

	// This method gives some (but not 100%) confidence that accessing the iName

	// does not cause a panic. This test works on assumtion that first TInt of

	// the descriptor holds "type length" information, and that type of a TBuf is

	// 0.

	//

	// Something like this sbould be provided by the descriptor class itself!

	//

	return ((iName.Length() | 0x30000000) == (TInt &)iName &&	// ... is really a TBuf?

			iName.Length() <= iName.MaxLength() &&				// ... length & maxlength seem reasonable

			iName.MaxSize() >= (sizeof(THostName) - 2*sizeof(TInt)));

	}

#endif