Modules/IPStack/tcp.h

   1 /*
   2  * Acess2 IP Stack
   3  * - TCP Definitions
   4  */
   5 #ifndef _TCP_H_
   6 #define _TCP_H_
   7
   8 #include "ipstack.h"
   9
  10 typedef struct sTCPHeader       tTCPHeader;
  11 typedef struct sTCPListener     tTCPListener;
  12 typedef struct sTCPConnection   tTCPConnection;
  13
  14 struct sTCPHeader
  15 {
  16         Uint16  SourcePort;
  17         Uint16  DestPort;
  18         Uint32  SequenceNumber;
  19         Uint32  AcknowlegementNumber;
  20         #if 0
  21         struct {
  22                 unsigned Reserved:      4;
  23                 unsigned DataOffset: 4; // Size of the header in 32-bit words
  24         } __attribute__ ((packed));
  25         #else
  26         Uint8   DataOffset;
  27         #endif
  28         #if 0
  29         struct {        // Lowest to Highest
  30                 unsigned FIN:   1;      // Last packet
  31                 unsigned SYN:   1;      // Synchronise Sequence Numbers
  32                 unsigned RST:   1;      // Reset Connection
  33                 unsigned PSH:   1;      // Push Function
  34                 unsigned ACK:   1;      // Acknowlegement field is significant
  35                 unsigned URG:   1;      // Urgent pointer is significant
  36                 unsigned ECE:   1;      // ECN-Echo
  37                 unsigned CWR:   1;      // Congestion Window Reduced
  38         } __attribute__ ((packed)) Flags;
  39         #else
  40         Uint8   Flags;
  41         #endif
  42         Uint16  WindowSize;
  43
  44         Uint16  Checksum;
  45         Uint16  UrgentPointer;
  46
  47         Uint8   Options[];
  48 } __attribute__ ((packed));
  49
  50 enum eTCPFlags
  51 {
  52         TCP_FLAG_FIN    = 0x01,
  53         TCP_FLAG_SYN    = 0x02,
  54         TCP_FLAG_RST    = 0x04,
  55         TCP_FLAG_PSH    = 0x08,
  56         TCP_FLAG_ACK    = 0x10,
  57         TCP_FLAG_URG    = 0x20,
  58         TCP_FLAG_ECE    = 0x40,
  59         TCP_FLAG_CWR    = 0x80
  60 };
  61
  62 struct sTCPListener
  63 {
  64         struct sTCPListener     *Next;  //!< Next server in the list
  65         Uint16  Port;           //!< Listening port (0 disables the server)
  66         tInterface      *Interface;     //!< Listening Interface
  67         tVFS_Node       Node;   //!< Server Directory node
  68          int    NextID;         //!< Name of the next connection
  69         tSpinlock       lConnections;   //!< Spinlock for connections
  70         tTCPConnection  *Connections;   //!< Connections (linked list)
  71          tTCPConnection *volatile NewConnections;
  72 };
  73
  74 struct sTCPConnection
  75 {
  76         struct sTCPConnection   *Next;
  77          int    State;  //!< Connection state (see ::eTCPConnectionState)
  78         Uint16  LocalPort;      //!< Local port
  79         Uint16  RemotePort;     //!< Remote port
  80         tInterface      *Interface;     //!< Listening Interface
  81         tVFS_Node       Node;   //!< Node
  82
  83          int    NextSequenceSend;       //!< Next sequence value for outbound packets
  84          int    NextSequenceRcv;        //!< Next expected sequence value for inbound
  85
  86          int    nQueuedPackets; //!< Number of packets not ACKed
  87         struct {
  88                  int    Sequence;
  89                 void    *Data;
  90         }       *QueuedPackets; //!< Non-ACKed packets
  91
  92
  93          int    nFuturePackets; //!< Number of packets recieved that are out of sequence
  94         struct {
  95                  int    SequenceNum;
  96                 void    *Data;
  97         }       **FuturePackets;        //!< Out of sequence packets
  98
  99         union {
 100                 tIPv4   v4;
 101                 tIPv6   v6;
 102         } RemoteIP;     //!< Remote IP Address
 103         // Type is determined by LocalInterface->Type
 104 };
 105
 106 enum eTCPConnectionState
 107 {
 108         TCP_ST_CLOSED,
 109         TCP_ST_HALFOPEN,
 110         TCP_ST_OPEN
 111 };
 112
 113 #endif