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