ipv4_frag.h

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#ifndef _IPV4_FRAG_H
#define _IPV4_FRAG_H
 
//Dependencies
#include "core/net.h"
#include "ipv4/ipv4.h"
 
//IPv4 fragmentation support
#ifndef IPV4_FRAG_SUPPORT
   #define IPV4_FRAG_SUPPORT ENABLED
#elif (IPV4_FRAG_SUPPORT != ENABLED && IPV4_FRAG_SUPPORT != DISABLED)
   #error IPV4_FRAG_SUPPORT parameter is not valid
#endif
 
//Support for overlapping fragments
#ifndef IPV4_OVERLAPPING_FRAG_SUPPORT
   #define IPV4_OVERLAPPING_FRAG_SUPPORT ENABLED
#elif (IPV4_OVERLAPPING_FRAG_SUPPORT != ENABLED && IPV4_OVERLAPPING_FRAG_SUPPORT != DISABLED)
   #error IPV4_OVERLAPPING_FRAG_SUPPORT parameter is not valid
#endif
 
//Reassembly algorithm tick interval
#ifndef IPV4_FRAG_TICK_INTERVAL
   #define IPV4_FRAG_TICK_INTERVAL 1000
#elif (IPV4_FRAG_TICK_INTERVAL < 10)
   #error IPV4_FRAG_TICK_INTERVAL parameter is not valid
#endif
 
//Maximum number of fragmented packets the host will accept
//and hold in the reassembly queue simultaneously
#ifndef IPV4_MAX_FRAG_DATAGRAMS
   #define IPV4_MAX_FRAG_DATAGRAMS 4
#elif (IPV4_MAX_FRAG_DATAGRAMS < 1)
   #error IPV4_MAX_FRAG_DATAGRAMS parameter is not valid
#endif
 
//Maximum datagram size the host will accept when reassembling fragments
#ifndef IPV4_MAX_FRAG_DATAGRAM_SIZE
   #define IPV4_MAX_FRAG_DATAGRAM_SIZE 8192
#elif (IPV4_MAX_FRAG_DATAGRAM_SIZE < 576)
   #error IPV4_MAX_FRAG_DATAGRAM_SIZE parameter is not valid
#endif
 
//Maximum time an IPv4 fragment can spend waiting to be reassembled
#ifndef IPV4_FRAG_TIME_TO_LIVE
   #define IPV4_FRAG_TIME_TO_LIVE 15000
#elif (IPV4_FRAG_TIME_TO_LIVE < 1000)
   #error IPV4_FRAG_TIME_TO_LIVE parameter is not valid
#endif
 
//Infinity is implemented by a very large integer
#define IPV4_INFINITY 0xFFFF
 
//C++ guard
#ifdef __cplusplus
extern "C" {
#endif
 
 
//CodeWarrior or Win32 compiler?
#if defined(__CWCC__) || defined(_WIN32)
   #pragma pack(push, 1)
#endif
 
 
typedef __packed_struct
{
   uint16_t first;
   uint16_t last;
   uint16_t next;
} Ipv4HoleDesc;
 
 
//CodeWarrior or Win32 compiler?
#if defined(__CWCC__) || defined(_WIN32)
   #pragma pack(pop)
#endif
 
 
typedef struct
{
   uint_t chunkCount;
   uint_t maxChunkCount;
   ChunkDesc chunk[N(IPV4_MAX_FRAG_DATAGRAM_SIZE) + 1];
} Ipv4ReassemblyBuffer;
 
 
typedef struct
{
   systime_t timestamp;         
   size_t headerLength;         
   size_t dataLen;              
   uint16_t firstHole;          
   Ipv4ReassemblyBuffer buffer; 
} Ipv4FragDesc;
 
 
//Tick counter to handle periodic operations
extern systime_t ipv4FragTickCounter;
 
//IPv4 datagram fragmentation and reassembly
error_t ipv4FragmentDatagram(NetInterface *interface,
   const Ipv4PseudoHeader *pseudoHeader, uint16_t id, const NetBuffer *payload,
   size_t payloadOffset, NetTxAncillary *ancillary);
 
void ipv4ReassembleDatagram(NetInterface *interface, const Ipv4Header *packet,
   size_t length, NetRxAncillary *ancillary);
 
void ipv4FragTick(NetInterface *interface);
 
Ipv4FragDesc *ipv4SearchFragQueue(NetInterface *interface,
   const Ipv4Header *packet);
 
void ipv4FlushFragQueue(NetInterface *interface);
 
Ipv4HoleDesc *ipv4FindHole(Ipv4FragDesc *frag, uint16_t offset);
void ipv4DumpHoleList(Ipv4FragDesc *frag);
 
//C++ guard
#ifdef __cplusplus
}
#endif
 
#endif