williamr@2: // Copyright (c) 2004-2009 Nokia Corporation and/or its subsidiary(-ies).
williamr@2: // All rights reserved.
williamr@2: // This component and the accompanying materials are made available
williamr@4: // under the terms of "Eclipse Public License v1.0"
williamr@2: // which accompanies this distribution, and is available
williamr@4: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
williamr@2: //
williamr@2: // Initial Contributors:
williamr@2: // Nokia Corporation - initial contribution.
williamr@2: //
williamr@2: // Contributors:
williamr@2: //
williamr@2: // Description:
williamr@2: // in_pkt.h - packet handling routines
williamr@2: // Generic packet handling utility for mapping packet handling to the RMBufChain.
williamr@2: //
williamr@2: 
williamr@2: 
williamr@2: 
williamr@2: /**
williamr@2:  @file in_pkt.h
williamr@2:  @publishedAll
williamr@2:  @released
williamr@2: */
williamr@2: 
williamr@2: #ifndef __IN_PKT_H__
williamr@2: #define __IN_PKT_H__
williamr@2: 
williamr@2: #include "ip6_hdr.h"	// ..should eventually be <inet/ip6_hdr.h>? -- msa
williamr@2: #include "ip4_hdr.h"
williamr@4: class RMBufChain;
williamr@2: 
williamr@4: 
williamr@4: #define TPACKETHEAD_FRAGMENT	1	//< Enable iFragment in TPacketHead
williamr@2: 
williamr@2: /**
williamr@2:  TScopeType is only provided so that "magic" constants can be
williamr@2:  avoided in the source code. However, the max value cannot be changed
williamr@2:  to anything from 0xF. The scope type is assumed to be 4 bits long
williamr@2:  in many occasions.
williamr@2: 
williamr@2:  The value of the scope type is directly bound the the IPv6 Scope
williamr@2:  level - 1. This can be done, as IPv6 Scope level 0 is not legal
williamr@2:  (or usable) in any context within the stack.
williamr@2:  This allows our non-standard network scope (= 0x10) to
williamr@2:  be coded internally in 4 bits (as 0xF).
williamr@2: 
williamr@2:  @publishedAll
williamr@2:  @released
williamr@2:  @since v7.0s
williamr@2: */
williamr@2: enum TScopeType
williamr@2: 	{
williamr@4: 	EScopeType_IF	= 0x0,	//< (= #KIp6AddrScopeNodeLocal - 1), id is interface index
williamr@4: 	EScopeType_IAP	= 0x1,	//< (= #KIp6AddrScopeLinkLocal - 1). id is IAP number
williamr@4: 	EScopeType_GLOBAL = 0xD,//< (= #KIp6AddrScopeGlobal - 1). id is global scope id
williamr@2: 	//
williamr@2: 	// no symbols defined for types 2..14 (they are also valid)
williamr@2: 	//
williamr@4: 	EScopeType_NET	= 0xF	//< (= #KIp6AddrScopeNetwork - 1), id is network number (must be the last entry)
williamr@2: 	};
williamr@2: 
williamr@2: //
williamr@2: //	TIpHeader
williamr@2: //	*********
williamr@2: class TIpHeader
williamr@2: 	/**
williamr@2: 	A simple help class that uses a union to merge handling of either an IPv4 or 
williamr@2: 	an IPv6 header. 
williamr@2: 	@since v7.0
williamr@2: 	@publishedAll
williamr@2: 	@released
williamr@2: 	*/
williamr@2: 	{
williamr@2: public:
williamr@2: 	/**
williamr@2: 	Gets the minimum header length.
williamr@2: 
williamr@2: 	IPv6 header is longer than minimum IPv4 header, thus
williamr@2: 	returned value is for IPv4. This function only defined
williamr@2: 	because it is required when this class is used as template
williamr@2: 	parameter in TInet6Packet.
williamr@2: 	
williamr@2: 	@return Minimum IPv4 header length
williamr@2: 	*/
williamr@2: 	inline static TInt MinHeaderLength() {return TInet6HeaderIP4::MinHeaderLength(); }
williamr@2: 	/**
williamr@2: 	Gets the maximum header length.
williamr@2: 
williamr@2: 	IPv6 header always shorter than maximum IPv4 header, thus
williamr@2: 	returned value is for IPv4. This function is only defined
williamr@2: 	because "header mapping" classes are expected to have it.
williamr@2: 	
williamr@2: 	@return Maximum IPv4 header length
williamr@2: 	*/
williamr@2: 	inline static TInt MaxHeaderLength() {return TInet6HeaderIP4::MaxHeaderLength(); }
williamr@2: 
williamr@2: 	union
williamr@2: 		{
williamr@2: 		TInet6HeaderIP4 ip4;
williamr@2: 		TInet6HeaderIP ip6;
williamr@2: 		};
williamr@2: 	};
williamr@2: 
williamr@2: 
williamr@2: 
williamr@2: class TInet6PacketBase
williamr@2: 	/**
williamr@2: 	* Thin base class for the TInet6Packet.
williamr@2: 	*/
williamr@2: 	{
williamr@2: public:
williamr@2: 	enum TAlign
williamr@2: 		{
williamr@4: 		EAlign1 = 0,	//< Align to byte (no align requirement)
williamr@4: 		EAlign2 = 1,	//< Align to 2 byte unit (even address)
williamr@4: 		EAlign4 = 3,	//< Align to 4 byte unit
williamr@4: 		EAlign8 = 7		//< Align to 8 byte unit
williamr@2: 		};
williamr@2: 
williamr@2: 	/**
williamr@2: 	Constructor.
williamr@2: 
williamr@2: 	@param aAlign	The align requirement.
williamr@2: 	*/
williamr@2: 	TInet6PacketBase(TAlign aAlign) : iLength(0), iAlign(aAlign) {}
williamr@2: 
williamr@2: 	/**
williamr@2: 	Length of the mapped region.
williamr@2: 
williamr@2: 	The real mapped length as computed by the Access function.
williamr@2: 	If access returned non-NULL, the following is always TRUE:
williamr@2: 
williamr@2: 	@li	aMin <= iLength
williamr@2: 	*/
williamr@2: 	TInt iLength;
williamr@2: 
williamr@2: 	IMPORT_C TUint8 *Access(RMBufChain &aPacket, TInt aOffset, TInt aSize, TInt aMin);
williamr@2: 
williamr@2: 	inline void SetAlign(TAlign aAlign)
williamr@2: 		/**
williamr@2: 		* Changes the align requirement.
williamr@2: 		*
williamr@2: 		* @param aAlign The new align requirement.
williamr@2: 		*/
williamr@2: 		{
williamr@2: 		iAlign = aAlign;
williamr@2: 		}
williamr@2: protected:
williamr@2: 	/**
williamr@2: 	The align requirement.
williamr@2: 	*/
williamr@2: 	TAlign iAlign;
williamr@2: 	};
williamr@2: 
williamr@2: // TInet6Packet template
williamr@2: // *********************
williamr@2: template <class T>
williamr@2: class TInet6Packet : public TInet6PacketBase
williamr@2: 	/**
williamr@2: 	Encapsulates an IPv6 packet header as a section of an RMBufChain.
williamr@2: 
williamr@2: 	The T template parameter should represent a packet header type. It should 
williamr@2: 	support static functions MaxHeaderLength() and MinHeaderLength() that return 
williamr@2: 	TInt values for maximum and minimum header lengths respectively.
williamr@2: 
williamr@2: 	@publishedAll
williamr@2: 	@released
williamr@2: 	@since v7.0
williamr@2: 	*/
williamr@2: 	{
williamr@2: public:
williamr@2: 	TInet6Packet(TAlign aAlign = EAlign4) : TInet6PacketBase(aAlign), iHdr(NULL)
williamr@2: 		/**
williamr@2: 		Default constructor.
williamr@2: 
williamr@2: 		Construct an empty mapping. To be usable, the Set() function
williamr@2: 		must be used.
williamr@2: 		*/
williamr@2: 		{}
williamr@2: 	TInet6Packet(RMBufChain &aPacket) : TInet6PacketBase(EAlign4)
williamr@2: 		/**
williamr@2: 		Constructor specifying a RMBufChain object.
williamr@2: 
williamr@2: 		Verify and arrange it so that a class T can be mapped
williamr@2: 		to a contiguous octets from the beginning of the RMBufChain
williamr@2: 		content, and set iHdr to point this area.
williamr@2: 
williamr@2: 		If this is not possible, iHdr is initialized to NULL.
williamr@2: 
williamr@2: 		@param	aPacket
williamr@2: 			Packet containing the header T at offset = 0
williamr@2: 		*/
williamr@2: 		{
williamr@2: 		iHdr = (T *)Access(aPacket, 0, T::MaxHeaderLength(), T::MinHeaderLength());
williamr@2: 		}
williamr@2: 
williamr@2: 	TInet6Packet(RMBufChain &aPacket, TInt aOffset, TAlign aAlign = EAlign4) : TInet6PacketBase(aAlign)
williamr@2: 		/**
williamr@2: 		Constructor specifying a RMBufChain object and an offset.
williamr@2: 
williamr@2: 		Verify and arrange it so that a class T can be mapped
williamr@2: 		to a contiguous octets starting at specified offset of
williamr@2: 		the RMBufChain content, and set iHdr to point this area.
williamr@2: 
williamr@2: 		If this is not possible, iHdr is initialized to NULL.
williamr@2: 
williamr@2: 		@param aPacket
williamr@2: 			Packet containing the header T at aOffset
williamr@2: 		@param aOffset
williamr@2: 			Offset of the header to be mapped.
williamr@2: 		@param aAlign
williamr@2: 			The alignement requirement.
williamr@2: 		*/
williamr@2: 		{
williamr@2: 		iHdr = (T *)Access(aPacket, aOffset, T::MaxHeaderLength(), T::MinHeaderLength());
williamr@2: 		}
williamr@2: 
williamr@2: 	void Set(RMBufChain &aPacket, TInt aOffset, TInt aSize)
williamr@2: 		/**
williamr@2: 		Sets the packet header from a specified RMBufChain object.
williamr@2: 
williamr@2: 		Verify and arrange it so that a aSize octets can be mapped
williamr@2: 		to a contiguous octets starting at specified offset of
williamr@2: 		the RMBufChain content, and set iHdr to point this area.
williamr@2: 
williamr@2: 		If this is not possible, iHdr is initialized to NULL.
williamr@2: 
williamr@2: 		Note that this differs from the contructors: the required
williamr@2: 		size is a parameter, and not determined by the T::MinHeaderLength().
williamr@2: 		However, the "T* iHdr" is set to point the start of the requested
williamr@2: 		area. It's a responsibility of the user of this method to know
williamr@2: 		whether using this pointer is safe with the specified size parameter.
williamr@2: 
williamr@2: 		@param	aPacket
williamr@2: 			Packet containing the header T at aOffset
williamr@2: 		@param	aOffset
williamr@2: 			Offset (position) of the header to be mapped
williamr@2: 		@param	aSize
williamr@2: 			Length of required contiguous memory
williamr@2: 		*/
williamr@2: 		{
williamr@2: 		iHdr = (T *)Access(aPacket, aOffset, aSize, aSize);
williamr@2: 		}
williamr@2: 
williamr@2: 	inline T& operator()()
williamr@2: 		{
williamr@2: 		return *iHdr;
williamr@2: 		}
williamr@2: 	/**
williamr@2: 	The pointer to the mapped region (if non-NULL). If NULL,
williamr@2: 	then there is no mapping, and iLength == 0.
williamr@2: 	*/
williamr@2: 	T *iHdr;
williamr@2: 	};
williamr@2: 
williamr@2: 
williamr@2: #endif