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 #include <adt.h>        // tRingBuffer
  10
  11 typedef struct sTCPHeader       tTCPHeader;
  12 typedef struct sTCPListener     tTCPListener;
  13 typedef struct sTCPStoredPacket tTCPStoredPacket;
  14 typedef struct sTCPConnection   tTCPConnection;
  15
  16 struct sTCPHeader
  17 {
  18         Uint16  SourcePort;
  19         Uint16  DestPort;
  20         Uint32  SequenceNumber;
  21         Uint32  AcknowlegementNumber;
  22         #if 0
  23         struct {        // Lowest to highest
  24                 unsigned Reserved:      4;
  25                 unsigned DataOffset: 4; // Size of the header in 32-bit words
  26         } __attribute__ ((packed));
  27         #else
  28         Uint8   DataOffset;
  29         #endif
  30         #if 0
  31         struct {        // Lowest to Highest
  32                 unsigned FIN:   1;      // Last packet
  33                 unsigned SYN:   1;      // Synchronise Sequence Numbers
  34                 unsigned RST:   1;      // Reset Connection
  35                 unsigned PSH:   1;      // Push Function
  36                 unsigned ACK:   1;      // Acknowlegement field is significant
  37                 unsigned URG:   1;      // Urgent pointer is significant
  38                 unsigned ECE:   1;      // ECN-Echo
  39                 unsigned CWR:   1;      // Congestion Window Reduced
  40         } __attribute__ ((packed)) Flags;
  41         #else
  42         Uint8   Flags;
  43         #endif
  44         Uint16  WindowSize;
  45
  46         Uint16  Checksum;
  47         Uint16  UrgentPointer;
  48
  49         Uint8   Options[];
  50 } __attribute__ ((packed));
  51
  52 enum eTCPFlags
  53 {
  54         TCP_FLAG_FIN    = 0x01,
  55         TCP_FLAG_SYN    = 0x02,
  56         TCP_FLAG_RST    = 0x04,
  57         TCP_FLAG_PSH    = 0x08,
  58         TCP_FLAG_ACK    = 0x10,
  59         TCP_FLAG_URG    = 0x20,
  60         TCP_FLAG_ECE    = 0x40,
  61         TCP_FLAG_CWR    = 0x80
  62 };
  63
  64 struct sTCPListener
  65 {
  66         struct sTCPListener     *Next;  //!< Next server in the list
  67         Uint16  Port;           //!< Listening port (0 disables the server)
  68         tInterface      *Interface;     //!< Listening Interface
  69         tVFS_Node       Node;   //!< Server Directory node
  70          int    NextID;         //!< Name of the next connection
  71         tShortSpinlock  lConnections;   //!< Spinlock for connections
  72         tTCPConnection  *Connections;   //!< Connections (linked list)
  73         tTCPConnection  *volatile NewConnections;
  74         tTCPConnection  *ConnectionsTail;
  75 };
  76
  77 struct sTCPStoredPacket
  78 {
  79         struct sTCPStoredPacket *Next;
  80         size_t  Length;
  81         Uint32  Sequence;
  82         Uint8   Data[];
  83 };
  84
  85 enum eTCPConnectionState
  86 {
  87         TCP_ST_CLOSED,          // 0 - Connection invalid
  88
  89         TCP_ST_SYN_SENT,        // 1 - SYN sent by local, waiting for SYN-ACK
  90         TCP_ST_SYN_RCVD,        // 2 - SYN recieved, SYN-ACK sent
  91
  92         TCP_ST_OPEN,            // 3 - Connection open
  93
  94         // Local Close
  95         TCP_ST_FIN_WAIT1,       // 4 - FIN sent, waiting for reply (ACK or FIN)
  96         TCP_ST_FIN_WAIT2,       // 5 - sent FIN acked, waiting for FIN from peer
  97         TCP_ST_CLOSING,         // 6 - Waiting for ACK of FIN (FIN sent and recieved)
  98         TCP_ST_TIME_WAIT,       // 7 - Waiting for timeout after local close
  99         // Remote close
 100         TCP_ST_CLOSE_WAIT,      // 8 - FIN recieved, waiting for user to close (error set, wait for node close)
 101         TCP_ST_LAST_ACK,        // 9 - FIN sent and recieved, waiting for ACK
 102         TCP_ST_FINISHED         // 10 - Essentially closed, all packets are invalid
 103 };
 104
 105 struct sTCPConnection
 106 {
 107         struct sTCPConnection   *Next;
 108         enum eTCPConnectionState        State;  //!< Connection state (see ::eTCPConnectionState)
 109         Uint16  LocalPort;      //!< Local port
 110         Uint16  RemotePort;     //!< Remote port
 111         tInterface      *Interface;     //!< Listening Interface
 112         tVFS_Node       Node;   //!< Node
 113
 114         Uint32  NextSequenceSend;       //!< Next sequence value for outbound packets
 115         Uint32  NextSequenceRcv;        //!< Next expected sequence value for inbound
 116
 117         #if 0
 118         /**
 119          * \brief Non-ACKed packets
 120          * \note Ring buffer
 121          * \{
 122          */
 123         tMutex  lNonACKedPackets;
 124         tTCPStoredPacket        *SentPackets;   //!< Non-acknowleged packets
 125         /**
 126          * \}
 127          */
 128         #endif
 129
 130         /**
 131          * \brief Unread Packets
 132          * \note Ring buffer
 133          * \{
 134          */
 135         tMutex  lRecievedPackets;
 136         tRingBuffer     *RecievedBuffer;
 137         /**
 138          * \}
 139          */
 140
 141         /**
 142          * \brief Out of sequence packets
 143          * \note Sorted list to improve times
 144          * \todo Convert this to a ring buffer and a bitmap of valid bytes
 145          * \{
 146          */
 147         #if CACHE_FUTURE_PACKETS_OR_BYTES == bytes
 148         Uint32  HighestSequenceRcvd;    //!< Highest sequence number (within window) recieved
 149         Uint8   *FuturePacketData;      //!< Future packet data (indexed by sequence number)
 150         Uint8   *FuturePacketValidBytes;        //!< Valid byte bitmap (WINDOW_SIZE/8 bytes)
 151         #else
 152         tShortSpinlock  lFuturePackets; //!< Future packets spinlock
 153         tTCPStoredPacket        *FuturePackets; //!< Out of sequence packets
 154         #endif
 155         /**
 156          * \}
 157          */
 158
 159         union {
 160                 tIPv4   v4;
 161                 tIPv6   v6;
 162         } RemoteIP;     //!< Remote IP Address
 163         // Type is determined by LocalInterface->Type
 164 };
 165
 166 #endif