//------------------------------------------------------------------------------
// Name: tcpip.h
// Func: header-file for tcpip.c
// Ver.: 1.1
// Date: January 2004
// Auth: Andreas Dannenberg
//       MSP430 Applications
//       Texas Instruments Inc.
// Rem.: -
//------------------------------------------------------------------------------

#ifndef __TCPIP_H
#define __TCPIP_H

#include "msp430x14x.h"

// easyWEB-stack definitions
#define MYIP_1               192                 // our internet protocol (IP) address
#define MYIP_2               168
#define MYIP_3               0
#define MYIP_4               30

#define SUBMASK_1            255                 // subnet mask
#define SUBMASK_2            255
#define SUBMASK_3            255
#define SUBMASK_4            0

#define GWIP_1               192                 // standard gateway (used if remote
#define GWIP_2               168                 // IP is no part of our subnet)
#define GWIP_3               0
#define GWIP_4               1

#define RETRY_TIMEOUT        8                   // wait max. 8 x 262ms for an ACK (about 2 sec.)
#define FIN_TIMEOUT          2                   // max. time to wait for an ACK of a FIN
                                                 // before closing TCP state-machine (about 0.5 s)
#define MAX_RETRYS           4                   // nr. of resendings before reset conn.
                                                 // total nr. of transmissions = MAX_RETRYS + 1

#define MAX_TCP_TX_DATA_SIZE 768                 // max. outgoing TCP data size
#define MAX_TCP_RX_DATA_SIZE 536                 // max. incoming TCP data size
                                                 // (increasing the buffer-size dramatically
                                                 // increases the transfer-speed!)
                                        
#define MAX_ETH_TX_DATA_SIZE 60                  // 2nd buffer, used for ARP, ICMP, TCP (even!)
                                                 // enough to echo 32 byte via ICMP

#define DEFAULT_TTL          64                  // Time To Live sent with packets

// Ethernet network layer definitions
#define ETH_DA_OFS           0                   // Destination MAC address (48 Bit)
#define ETH_SA_OFS           6                   // Source MAC address (48 Bit)
#define ETH_TYPE_OFS         12                  // Type field (16 Bit)
#define ETH_DATA_OFS         14                  // Frame Data
#define ETH_HEADER_SIZE      14

#define FRAME_ARP            (0x0806)            // frame types (stored in Type/Length field)
#define FRAME_IP             (0x0800)

// IPv4 layer definitions
#define IP_VER_IHL_TOS_OFS   (ETH_DATA_OFS + 0)  // Version, Header Length, Type of Service
#define IP_TOTAL_LENGTH_OFS  (ETH_DATA_OFS + 2)  // IP Frame's Total Length
#define IP_IDENT_OFS         (ETH_DATA_OFS + 4)  // Identifying Value
#define IP_FLAGS_FRAG_OFS    (ETH_DATA_OFS + 6)  // Flags and Fragment Offset
#define IP_TTL_PROT_OFS      (ETH_DATA_OFS + 8)  // Frame's Time to Live, Protocol
#define IP_HEAD_CHKSUM_OFS   (ETH_DATA_OFS + 10) // IP Frame's Header Checksum
#define IP_SOURCE_OFS        (ETH_DATA_OFS + 12) // Source Address (32 Bit)
#define IP_DESTINATION_OFS   (ETH_DATA_OFS + 16) // Destination Address (32 Bit)
#define IP_DATA_OFS          (ETH_DATA_OFS + 20) // Frame Data (if no options)
#define IP_HEADER_SIZE       20                  // w/o options

#define IP_VER_IHL           (0x4500)            // IPv4, Header Length = 5x32 bit
#define IP_TOS_D             (0x0010)            // TOS low delay
#define IP_TOS_T             (0x0008)            // TOS high throughput
#define IP_TOS_R             (0x0004)            // TOS high reliability

#define IP_FLAG_DONTFRAG     (0x4000)            // don't fragment IP frame
#define IP_FLAG_MOREFRAG     (0x2000)            // more fragments available
#define IP_FRAGOFS_MASK      (0x1fff)            // indicates where this fragment belongs

#define PROT_ICMP            1                   // Internet Control Message Protocol
#define PROT_TCP             6                   // Transmission Control Protocol
#define PROT_UDP             17                  // User Datagram Protocol

// ARP definitions
#define ARP_HARDW_OFS        (ETH_DATA_OFS + 0)  // Hardware address type
#define ARP_PROT_OFS         (ETH_DATA_OFS + 2)  // Protocol
#define ARP_HLEN_PLEN_OFS    (ETH_DATA_OFS + 4)  // byte length of each hardw. / prot. address
#define ARP_OPCODE_OFS       (ETH_DATA_OFS + 6)  // Opcode
#define ARP_SENDER_HA_OFS    (ETH_DATA_OFS + 8)  // Hardw. address of sender of this packet
#define ARP_SENDER_IP_OFS    (ETH_DATA_OFS + 14) // IP address of sender
#define ARP_TARGET_HA_OFS    (ETH_DATA_OFS + 18) // Hardw. address of target of this packet
#define ARP_TARGET_IP_OFS    (ETH_DATA_OFS + 24) // IP address of target
#define ARP_FRAME_SIZE       28

#define HARDW_ETH10          1                   // hardware-type 10Mbps Ethernet
#define IP_HLEN_PLEN         (0x0604)            // MAC = 6 byte long, IP = 4 byte long
#define OP_ARP_REQUEST       1                   // operations for ARP-frames
#define OP_ARP_ANSWER        2

// ICMP definitions
#define ICMP_TYPE_CODE_OFS   (IP_DATA_OFS + 0)   // type of message
#define ICMP_CHKSUM_OFS      (IP_DATA_OFS + 2)   // checksum of ICMP-message (16 bit)
#define ICMP_DATA_OFS        (IP_DATA_OFS + 4)
#define ICMP_HEADER_SIZE     4

#define ICMP_ECHO            8                   // message is an echo request
#define ICMP_ECHO_REPLY      0                   // message is an echo reply

// TCP layer definitions
#define TCP_SRCPORT_OFS      (IP_DATA_OFS + 0)   // Source Port (16 bit)
#define TCP_DESTPORT_OFS     (IP_DATA_OFS + 2)   // Destination Port (16 bit)
#define TCP_SEQNR_OFS        (IP_DATA_OFS + 4)   // Sequence Number (32 bit)
#define TCP_ACKNR_OFS        (IP_DATA_OFS + 8)   // Acknowledge Number (32 bit)
#define TCP_DATA_CODE_OFS    (IP_DATA_OFS + 12)  // Data Offset and Control Bits (16 bit)
#define TCP_WINDOW_OFS       (IP_DATA_OFS + 14)  // Window Size (16 bit)
#define TCP_CHKSUM_OFS       (IP_DATA_OFS + 16)  // Checksum Field (16 bit)
#define TCP_URGENT_OFS       (IP_DATA_OFS + 18)  // Urgent Pointer (16 bit)
#define TCP_DATA_OFS         (IP_DATA_OFS + 20)  // Frame Data (if no options)
#define TCP_HEADER_SIZE      20                  // size w/o options

#define DATA_OFS_MASK        (0xf000)            // number of 32 bit words in the TCP Header

#define TCP_CODE_FIN         (0x0001)
#define TCP_CODE_SYN         (0x0002)
#define TCP_CODE_RST         (0x0004)
#define TCP_CODE_PSH         (0x0008)
#define TCP_CODE_ACK         (0x0010)
#define TCP_CODE_URG         (0x0020)

#define TCP_OPT_MSS          (0x0204)            // Type 2, Option Length 4 (Max. Segment Size)
#define TCP_OPT_MSS_SIZE     4

// define some TCP standard-ports, useful for testing...
#define TCP_PORT_ECHO        7                   // echo
#define TCP_PORT_DISCARD     9                   // discard
#define TCP_PORT_DAYTIME     13                  // daytime
#define TCP_PORT_QOTD        17                  // quote of the day
#define TCP_PORT_CHARGEN     19                  // character generator
#define TCP_PORT_HTTP        80                  // word wide web HTTP

// macro: word access to MSP430 memory location
#define ACCESS_UINT(Base, Offset)   (*(unsigned int *)((unsigned char *)&(Base) + (Offset)))
// macro: endianess conversion
#define SWAPB(Word)                 ((unsigned int)((Word) << 8) | ((Word) >> 8))

// typedefs
typedef enum                                     // states of the TCP-state machine
{                                                // according to RFC793
  CLOSED,                                        
  LISTENING,
  SYN_SENT,
  SYN_RECD,
  ESTABLISHED,
  FIN_WAIT_1,
  FIN_WAIT_2,
  CLOSE_WAIT,
  CLOSING,
  LAST_ACK,
  TIME_WAIT
} TTCPStateMachine;

typedef enum                                     // type of last frame sent. used
{                                                // for retransmissions
  ARP_REQUEST,                                   
  TCP_SYN_FRAME,
  TCP_SYN_ACK_FRAME,
  TCP_FIN_FRAME,
  TCP_DATA_FRAME
} TLastFrameSent;

// definitions for 'TransmitControl'
#define SEND_FRAME1                    (0x01)
#define SEND_FRAME2                    (0x02)

// definitions for 'TCPFlags'
#define TCP_ACTIVE_OPEN                (0x01)    // easyWEB shall initiate a connection
#define IP_ADDR_RESOLVED               (0x02)    // IP sucessfully resolved to MAC
#define TCP_TIMER_RUNNING              (0x04)
#define TIMER_TYPE_RETRY               (0x08)
#define TCP_CLOSE_REQUESTED            (0x10)

// definitions for 'SocketStatus'
#define SOCK_ACTIVE                    (0x01)    // state machine NOT closed
#define SOCK_CONNECTED                 (0x02)    // user may send & receive data
#define SOCK_DATA_AVAILABLE            (0x04)    // new data available
#define SOCK_TX_BUF_RELEASED           (0x08)    // user may fill buffer
#define SOCK_ERROR_MASK                (0xf0)    // bit-mask to check for errors
#define SOCK_ERR_OK                    (0x00)    // no error
#define SOCK_ERR_ARP_TIMEOUT           (0x10)    // timeout waiting for an ARP-REPLY
#define SOCK_ERR_TCP_TIMEOUT           (0x20)    // timeout waiting for an ACK
#define SOCK_ERR_CONN_RESET            (0x30)    // connection was reset by the other TCP
#define SOCK_ERR_REMOTE                (0x40)    // remote TCP caused fatal error
#define SOCK_ERR_ETHERNET              (0x50)    // network interface error (timeout)

// exported functions
// easyWEB-API functions
void TCPLowLevelInit(void);                      // setup timer, LAN-controller, flags...
void TCPPassiveOpen(void);                       // listen for a connection
void TCPActiveOpen(void);                        // open connection
void TCPClose(void);                             // close connection
void TCPReleaseRxBuffer(void);                   // indicate to discard rec'd packet
void TCPTransmitTxBuffer(void);                  // initiate transfer after TxBuffer is filled
void DoNetworkStuff(void);                       // network and TCP/IP event processing

// exported constants
extern const unsigned int MyIP[];                // local IP address
extern const unsigned int SubnetMask[];          // subnet mask (outbount connections)
extern const unsigned int GatewayIP[];           // gateway IP addr (outbount connections)

// exported variables
// easyWEB-API global vars and flags
extern unsigned char SocketStatus;               // API status variable
extern unsigned int TCPLocalPort;                // TCP ports
extern unsigned int TCPRemotePort;
extern unsigned int RemoteMAC[3];                // MAC address of current TCP-session
extern unsigned int RemoteIP[2];                 // IP address of current TCP-session
extern unsigned int TCPRxDataCount;              // nr. of bytes rec'd (TCP_RX_BUF)
extern unsigned int TCPTxDataCount;              // nr. of bytes to send (TCP_TX_BUF)
extern unsigned int TxFrame1Mem[];               // outgoing TCP segment
extern unsigned int RxTCPBufferMem[];            // data of received TCP segment

// easyWEB-API TCP data buffer-pointers
#define TCP_TX_BUF      ((unsigned char *)TxFrame1Mem + ETH_HEADER_SIZE + \
                          IP_HEADER_SIZE + TCP_HEADER_SIZE)
#define TCP_RX_BUF      ((unsigned char *)RxTCPBufferMem)

#endif