From geof@imagen.UUCP Thu May 15 20:13:10 1986
Path: seismo!caip!topaz!ll-xn!mit-amt!mit-eddie!genrad!decvax!decwrl!sun!saber!imagen!geof
From: geof@imagen.UUCP
Newsgroups: net.sources
Subject: TINYTCP-public domain tcp/ip implementation
Message-ID: <366@imagen.UUCP>
Date: 16 May 86 00:13:10 GMT
Distribution: net
Organization: IMAGEN Corporation, Santa Clara, CA 95052-8101
Lines: 1524

#!/bin/sh
: "This is a shell archive, meaning:                              "
: "1. Remove everything above the #! /bin/sh line.                "
: "2. Save the resulting test in a file.                          "
: "3. Execute the file with /bin/sh (not csh) to create the files:"
: "	README"
: "	arp.c"
: "	sed.c"
: "	sed.h"
: "	tinyftp.c"
: "	tinytcp.c"
: "	tinytcp.h"
: "This archive created:  Thu May 15 16:43:07 PDT 1986 "
echo file: README
sed 's/^X//' >README << 'END-of-README'
X
X    TinyTcp Public Domain Release
X
XThe files in this release contain a simple implementation of
XTCP & FTP, suitable for burning into ROM.  It is, in effect,
Xa big hack put together in two or three days.  It works for
Xus, though, and you might like it, too.  Warning: the code
Xwas intended for a 68000, and doesn't have any byte swapping
Xsupport in it.  Shouldn't be too hard to add, though.
X
X    - Geof Cooper
X      Imagen Corporation
X      [imagen!geof@decwrl.dec.com]
X      April 16, 1986
X
XThe package requires some system support:
X
X    clock_ValueRough() - should be a procedure that returns the current
X        value of a millisecond clock.  The procedure is called frequently,
X        so that interrupts are not needed to service the clock.  Our
X        implementation polls the real time timer and assumes that it is
X        called frequently enough so that it doesn't miss clock ticks (Since
X        the timer is only used for network timeouts, it doesn't really matter
X        if it does miss clock ticks, of course).  Systems without a clock
X        could probably get by with a procedure that increments a static
X        variable and returns it, by adjusting the timeout constants in the
X        program.
X
X    Network driver - some network interface  driver is needed.  A driver for a
X        3Com multibus (ethernet) board is included; this board isn't made anymore
X        (at least not by 3Com), so you'll probably need to write a driver for the
X        board in your system.
X
X
XGuide to source files:
X
X    sed.c - Simple Ethernet Driver - Driver for 3Com multibus card.  If you
X            have another type of Ethernet board, you can use this driver as
X            a template.
X
X    sed.h - header file for the above.
X
X    arp.c - Implementation of Address Resolution Protocol.  Note that there
X            is no arp "mapping" per se.  The higher level code (tcp, in this case)
X            is required to keep track of internet and ethernet addresses.
X
X    tinytcp.c - Implementation of TCP.
X
X    tinytcp.h - Header file for above, and for everything else.
X
X    tinyftp.c - Implementation of FTP, only allows files to be retrieved, not sent.
END-of-README
echo file: arp.c
sed 's/^X//' >arp.c << 'END-of-arp.c'
X/* 
X * SAR: Simple Address Resolution Protocol Implementation
X * Written by Geoffrey Cooper, September 27, 1983
X * 
X * This package implements a very simple version of the Plummer Address
X * Resolution Protocol (RFC 826).  It allows clients to resolve Internet
X * addresses into Ethernet addresses, and knows how to respond to an
X * address resolution request (when the transmit buffer is free).
X * 
X * Routines:
X * 
X *  sar_CheckPacket( pb ) => 1, if ARP packet and processed, 0 otherwise
X *  sar_MapIn2Eth( ina, ethap ) => 1 if did it, 0 if couldn't.
X *
X * Copyright (C) 1983, 1986 IMAGEN Corporation
X *  "This code may be duplicated in whole or in part provided that [1] there
X *   is no commercial gain involved in the duplication, and [2] that this
X *   copyright notice is preserved on all copies.  Any other duplication
X *   requires written notice of the author."
X * 
X */
X#include "tinytcp.h"
X
Xsar_CheckPacket(ap)
X    register arp_Header *ap;
X{
X    register arp_Header *op;
X
X    if ( ap->hwType != arp_TypeEther || /* have ethernet hardware, */
X         ap->protType != 0x800 ||       /* and internet software, */
X         ap->opcode != ARP_REQUEST ||   /* and be a resolution req. */
X         ap->dstIPAddr != sin_lclINAddr /* for my addr. */
X       ) return ( 0 );                  /* .... or we ignore it. */
X
X    /* format response. */
X    op = (arp_Header *)sed_FormatPacket(ap->srcEthAddr, 0x806);
X    op->hwType = arp_TypeEther;
X    op->protType = 0x800;
X    op->hwProtAddrLen = (sizeof(eth_HwAddress) << 8) + sizeof(in_HwAddress);
X    op->opcode = ARP_REPLY;
X    op->srcIPAddr = sin_lclINAddr;
X    MoveW(sed_lclEthAddr, op->srcEthAddr, sizeof(eth_HwAddress));
X    ap->dstIPAddr = op->srcIPAddr;
X    MoveW(ap->srcEthAddr, op->dstEthAddr, sizeof(eth_HwAddress));
X
X    sed_Send(sizeof(arp_Header));
X    
X    return ( 1 );
X}
X
X/* 
X * Do an address resolution bit.
X */
Xsar_MapIn2Eth(ina, ethap)
X    longword ina;
X    eth_HwAddress *ethap;
X{
X    register arp_Header *op;
X    extern in_HwAddress sin_lclINAddr;
X    register i;
X    longword endTime;
X    longword rxMitTime;
X
X    sed_Receive( 0 );
X    endTime = clock_ValueRough() + 2000;
X    while ( endTime > clock_ValueRough() ) {
X        op = (arp_Header *)sed_FormatPacket(&sed_ethBcastAddr[0], 0x806);
X        op->hwType = arp_TypeEther;
X        op->protType = 0x800;
X        op->hwProtAddrLen = (sizeof(eth_HwAddress) << 8) + sizeof(in_HwAddress);
X        op->opcode = ARP_REQUEST;
X        op->srcIPAddr = sin_lclINAddr;
X        MoveW(sed_lclEthAddr, op->srcEthAddr, sizeof(eth_HwAddress));
X        op->dstIPAddr = ina;
X
X        /* ...and send the packet */
X        sed_Send( sizeof(arp_Header) );
X
X        rxMitTime = clock_ValueRough() + 250;
X        while ( rxMitTime > clock_ValueRough() ) {
X            op = (arp_Header *)sed_IsPacket();
X            if ( op ) {
X                if ( sed_CheckPacket(op, 0x806) == 1 &&
X                    op->protType == 0x800 &&
X                    op->srcIPAddr == ina &&
X                    op->opcode == ARP_REPLY ) {
X                    MoveW(op->srcEthAddr, ethap, sizeof(eth_HwAddress));
X                    return ( 1 );
X                }
X                sed_Receive(op);
X            }
X        }
X    }
X    return ( 0 );
X}
END-of-arp.c
echo file: sed.c
sed 's/^X//' >sed.c << 'END-of-sed.c'
X/* 
X * Ethernet Driver.
X * A Very Simple set of ethernet driver primitives.  The ethernet (3com Mbus)
X * interface is controlled by busy-waiting, the application is handed the
X * location of on-board packet buffers, and allowed to fill in the
X * transmit buffer directly.  The interface is entirely blocking.
X * 
X * Written March, 1986 by Geoffrey Cooper
X *
X * Copyright (C) 1986, IMAGEN Corporation
X *  "This code may be duplicated in whole or in part provided that [1] there
X *   is no commercial gain involved in the duplication, and [2] that this
X *   copyright notice is preserved on all copies.  Any other duplication
X *   requires written notice of the author."
X * 
X * Primitives:
X *  sed_Init()  -- Initialize the package
X *  sed_FormatPacket( destEAddr ) => location of transmit buffer
X *  sed_Send( pkLength ) -- send the packet that is in the transmit buffer
X *  sed_Receive( recBufLocation ) -- enable receiving packets.
X *  sed_IsPacket() => location of packet in receive buffer
X *  sed_CheckPacket( recBufLocation, expectedType )
X *
X * Global Variables:
X *  sed_lclEthAddr -- Ethernet address of this host.
X *  sed_ethBcastAddr -- Ethernet broadcast address.
X */
X
X#include "tinytcp.h"
X#include "sed.h"
X
X#define en10pages        ((en10size) >> pageshift)
X
Xoctet *sed_va;                          /* virtual address of ethernet card */
Xeth_HwAddress sed_lclEthAddr;           /* local ethernet address */
Xeth_HwAddress sed_ethBcastAddr;         /* Ethernet broadcast address */
XBOOL sed_respondARPreq;                 /* controls responses to ARP req's */
Xchar bufAinUse, bufBinUse;              /* tell whether bufs are in use */
X
X/* 
X *  Initialize the Ethernet Interface, and this package.  Enable input on
X * both buffers.
X */
Xsed_Init()
X{
X    int recState;
X    register i, j;
X
X    recState = 7;                       /* == mine + broad - errors */
X
X    /* Map the Ethernet Interface in, and initialize sed_va */
X    sed_va = (octet *)SED3CVA;        /* our virtual addr */
X
X    /* Map memory for 3Com board (must be 8k boundary) */
X    /* INSERT CODE HERE */
X    map_ethernet_board();
X
X    /* Reset the Ethernet controller */
X    MECSR(sed_va) = RESET;
X    for (i=0; i<10; i++);           /* delay a bit... */
X
X    /* just copy on-board ROM to on-board RAM, to use std. address */
X    Move(MEAROM(sed_va), sed_lclEthAddr, 6);
X    Move(sed_lclEthAddr, MEARAM(sed_va), 6);
X    
X    MECSR(sed_va) |= AMSW;        /* and tell board we did it */
X
X    /*
X     * and initialize the exported variable which gives the Eth broadcast
X     * address, for everyone else to use. 
X     */
X    for (i=0; i<3; i++) sed_ethBcastAddr[i] = 0xFFFF;
X    
X    /* accept packets addressed for us and broadcast packets */
X
X    MECSR(sed_va) = (MECSR(sed_va)&~PA) | recState;
X
X    /* declare both buffers in use... */
X    bufAinUse = bufBinUse = TRUE;
X
X}
X
X/* 
X * Format an ethernet header in the transmit buffer, and say where it is.
X * Note that because of the way the 3Com interface works, we need to know
X * how long the packet is before we know where to put it.  The solution is
X * that we format the packet at the BEGINNING of the transmit buffer, and
X * later copy it (carefully) to where it belongs.  Another hack would be
X * to be inefficient about the size of the packet to be sent (always send
X * a larger ethernet packet than you need to, but copying should be ok for
X * now.
X */
Xoctet *
Xsed_FormatPacket( destEAddr, ethType )
X        register octet *destEAddr;
X{
X    register octet *xMitBuf;
X    
X    xMitBuf = &((octet *)MEXBUF(sed_va))[-0x800];
X    Move( destEAddr, xMitBuf, 6 );
X    Move( sed_lclEthAddr, xMitBuf + 6, 6 );
X    *((short *)(xMitBuf+12)) = ethType;
X    return ( xMitBuf+14 );
X}
X
X/*
X *  Send a packet out over the ethernet.  The packet is sitting at the
X * beginning of the transmit buffer.  The routine returns when the
X * packet has been successfully sent.
X */
Xsed_Send( pkLengthInOctets )
X    register int pkLengthInOctets;
X{
X    register octet *fromO, *toO;
X    register pkLength;
X    register csr;
X
X    pkLengthInOctets += 14;             /* account for Ethernet header */
X    pkLengthInOctets = (pkLengthInOctets + 1) & (~1);
X
X    if (pkLengthInOctets < E10P_MIN) 
X        pkLengthInOctets = E10P_MIN; /* and min. ethernet len */
X
X    /*  and copy the packet where it belongs */
X    pkLength = pkLengthInOctets;
X    fromO = &((octet *)MEXBUF(sed_va))[-0x800] + pkLength;
X    toO = ((octet *)MEXBUF(sed_va));
X
X    while ( pkLength-- ) *--toO = *--fromO;
X    
X    /* send the packet */
X    
X    MEXHDR(sed_va) = 2048 - pkLengthInOctets;
X    MECSR(sed_va) |= TBSW;
X
X    /* and wait until it has really been sent. */
X
X    for (pkLength=0; pkLength < 15; pkLength++) {
X        while ( (! ((csr = MECSR(sed_va)) & JAM)) && (csr & TBSW) )
X            ;
X        if (csr & JAM ) {
X            /* Ethernet Collision detected... */
X#ifdef DEBUG
X            printf("sed: JAM: MECSR=%x\n", csr);
X#endif
X            MEBACK(sed_va) = clock_ValueRough();
X            MECSR(sed_va) |= JAM;
X        } else break;
X    }
X    if ( pkLength == 15 ) SysBug("Go and Buy a New Ethernet Interface.");
X
X    /*  else we sent the packet ok. */
X}
X
X/* 
X *  Enable the Ethernet interface to receive packets from the network.  If
X * the argument is zero, enable both buffers.  If the argument is nonzero,
X * take it as the address of the buffer to be enabled.
X */
Xsed_Receive( recBufLocation )
X    octet *recBufLocation;
X{
X    word enables = 0;
X
X    if (recBufLocation == 0) {
X        bufAinUse = FALSE;
X        bufBinUse = FALSE;
X        enables = (ABSW | BBSW);
X    }
X    recBufLocation -= 16;
X    if (recBufLocation == ((octet *)MEAHDR(sed_va))) {
X        bufAinUse = FALSE;
X        enables = ABSW;
X        }
X    if (recBufLocation == ((octet *)MEBHDR(sed_va))) {
X        bufBinUse = FALSE;
X        enables = BBSW;
X    }
X
X    MECSR (sed_va) |= enables;
X}
X
X/* 
X * Test for the arrival of a packet on the Ethernet interface.  The packet may
X * arrive in either buffer A or buffer B; the location of the packet is
X * returned.  If no packet is returned withing 'timeout' milliseconds,
X * then the routine returns zero.
X * 
X * Note: ignores ethernet errors.  may occasionally return something
X * which was received in error.
X */
X
Xoctet *
Xsed_IsPacket()
X{
X    register oldStatus;
X    register octet *pb;
X    
X    pb = 0;
X    if ( ! bufAinUse && (MECSR(sed_va)&ABSW) == 0 ) 
X        pb = (octet *)MEAHDR(sed_va);
X    if ( ! pb && ! bufBinUse && (MECSR(sed_va)&BBSW) == 0 )
X        pb = (octet *)MEBHDR(sed_va);
X
X    if ( pb ) {
X        if ( ((octet *)pb) == ((octet *)MEAHDR(sed_va)) ) bufAinUse = 1;
X        else bufBinUse = 1;
X        pb += 16;                       /* get past the ethernet header */
X    }
X
X    return ( pb );
X}
X
X/* 
X *  Check to make sure that the packet that you received was the one that
X * you expected to get.
X */
Xsed_CheckPacket( recBufLocation, expectedType )
X    word *recBufLocation;
X    word expectedType;
X{
X    register recHeader = recBufLocation[-8];
X    if ( (recHeader&R_ERROR) != 0 ||
X         (recHeader&R_OFFSET) < E10P_MIN ) {
X         return ( -1 );
X    }
X    if ( recBufLocation[-1] != expectedType ) {
X        return ( 0 );
X    }
X    return (1);
X}
END-of-sed.c
echo file: sed.h
sed 's/^X//' >sed.h << 'END-of-sed.h'
X/* 
X *  Header file for very simple ethernet driver, based on 3Com Multibus
X *  board.
X *
X * Copyright (C) 1986, IMAGEN Corporation
X *  "This code may be duplicated in whole or in part provided that [1] there
X *   is no commercial gain involved in the duplication, and [2] that this
X *   copyright notice is preserved on all copies.  Any other duplication
X *   requires written notice of the author."
X */
X
X#define	en10size        (8*1024)	/* size of interface memory */
X#define	en10pages	((en10size) >> pageshift)
X#define E10P_MIN	60              /* Minimum Ethernet packet size */
X
X/* 
X * The position of the 3Com interface in virtual memory.  If we're
X * Running the bootloader function, then it must be in the last 8k
X * of virtual addresses.
X */
X#ifdef BOOTLOADER
X#define SED3CVA vm_3ComAdr /* hack, only need pb68.h if bootloader */
X#endif
X#ifndef SED3CVA
X#define SED3CVA 0x1c000
X#endif
X
X/* 10Mb Ethernet interface addresses */
X
X#define	MECSR(eth_va)	*(word*)(((octet *) eth_va) + 0x0)
X#define	MEBACK(eth_va)	*(word*)(((octet *) eth_va) + 0x2)
X#define	MEAROM(eth_va)	(word*)(((octet *) eth_va) + 0x400)
X#define	MEARAM(eth_va)	(word*)(((octet *) eth_va) + 0x600)
X#define	MEXHDR(eth_va)	*(word*)(((octet *) eth_va) + 0x800)
X#define	MEXBUF(eth_va)	(word*)(((octet *) eth_va) + 0x1000)
X#define	MEAHDR(eth_va)	(word*)(((octet *) eth_va) + 0x1000)
X#define	MEBHDR(eth_va)	(word*)(((octet *) eth_va) + 0x1800)
X
X/* control/status register fields */
X
X#define	BBSW		0x8000	/* Buffer B belongs to Network */
X#define	ABSW		0x4000	/* Buffer A belongs to Network */
X#define	TBSW		0x2000	/* Transmit buffer belongs to Network */
X#define	JAM		0x1000	/* Set when transmit collision */
X#define	AMSW		0x0800	/* 
X#define	RBBA		0x0400	/* Oldest received packet is in B */
X/*#define	UNUSED		0x0200 */
X#define	RESET		0x0100	/* Reset the controller */
X#define	BINT		0x0080	/* Interrupt when BBSW=>0 (packet in B) */
X#define	AINT		0x0040	/* Interrupt when ABSW=>0 (packet in A) */
X#define	TINT		0x0020	/* Interrupt when TBSW=>0 (transmit done) */
X#define	JINT		0x0010	/* Enable interrupts when JAM=>1 */
X#define	PA		0x000F	/* Which packets should be received? */
X#define INTENABLS	0x00F0
X
X/*
X * Receiver Header Fields: 
X * The receiver header is the first (short) word of the receive buffer.  It
X * includes such information as how big the packet is, whether it was a
X * broadcast, whether there was an error in receiving it, etc.
X */
X
X#define	R_FCS		0x8000	/* fcs error */
X#define	R_BCAST		0x4000	/* packet was NOT a broadcast */
X#define	R_RANGE		0x2000	/* range error (size of pkt?) */
X#define	R_MATCH		0x1000	/* packet is multicast (i.e., address
X				   received is not that of the interface) */
X#define	R_FRAME		0x0800	/* framing error */
X#define	R_ERROR		0x8800	/* was there any error */
X#define	R_OFFSET	0x07FF	/* packet length + 1 word */
X
Xextern octet *sed_FormatPacket(), *sed_WaitPacket();
X
X#ifdef BOOTLOADER
X#define ConsPrintf printf
X#endif
END-of-sed.h
echo file: tinyftp.c
sed 's/^X//' >tinyftp.c << 'END-of-tinyftp.c'
X/*
X * tinyftp.c - user ftp built on tinytcp.c
X *
X * Written March 31, 1986 by Geoffrey Cooper
X *
X * Copyright (C) 1986, IMAGEN Corporation
X *  "This code may be duplicated in whole or in part provided that [1] there
X *   is no commercial gain involved in the duplication, and [2] that this
X *   copyright notice is preserved on all copies.  Any other duplication
X *   requires written notice of the author."
X */
X#include "tinytcp.h"
X
Xtcp_Socket ftp_ctl, ftp_data, ftp_data2;
Xbyte ftp_cmdbuf[120];
Xint ftp_cmdbufi;
X
Xbyte ftp_outbuf[80];
Xint ftp_outbufix, ftp_outbuflen;
X    
Xshort ftp_rcvState;
X#define ftp_StateGETCMD     0       /* get a command from the user */
X#define ftp_StateIDLE       1       /* idle connection */
X#define ftp_StateINCOMMAND  2       /* command sent, awaiting response */
X#define ftp_StateRCVRESP    3       /* received response, need more data */
X
Xchar *ftp_script[7];
Xint ftp_scriptline;
Xchar ftp_retrfile[80];
XBOOL ftp_echoMode;
X
Xftp_ctlHandler(s, dp, len)
X    tcp_Socket *s;
X    byte *dp;
X    int len;
X{
X    byte c, *bp, data[80];
X    int i;
X
X    if ( dp == 0 ) {
X        tcp_Abort(&ftp_data);
X        return;
X    }
X
X    do {
X        i = len;
X        if ( i > sizeof data ) i = sizeof data;
X        MoveW(dp, data, i);
X        len -= i;
X        bp = data;
X        while ( i-- > 0 ) {
X            c = *bp++;
X            if ( c != '\r' ) {
X                if ( c == '\n' ) {
X                    ftp_cmdbuf[ftp_cmdbufi] = 0;
X                    ftp_commandLine();
X                    ftp_cmdbufi = 0;
X                } else if ( ftp_cmdbufi < (sizeof ftp_cmdbuf)-1 ) {
X                    ftp_cmdbuf[ftp_cmdbufi++] = c;
X                }
X            }
X        }
X    } while ( len > 0 );
X}
X
Xftp_commandLine()
X{
X    printf("> %s\n", ftp_cmdbuf);
X    switch(ftp_rcvState) {
X     case ftp_StateIDLE:
X        if ( ftp_cmdbuf[3] == '-' )
X            ftp_rcvState = ftp_StateRCVRESP;
X        break;
X
X     case ftp_StateINCOMMAND:
X        if ( ftp_cmdbuf[3] == '-' )
X            ftp_rcvState = ftp_StateRCVRESP;
X     case ftp_StateRCVRESP:
X        if ( ftp_cmdbuf[3] == ' ' )
X            ftp_rcvState = ftp_StateIDLE;
X        break;
X    }
X}
X
Xftp_Abort()
X{
X    tcp_Abort(&ftp_ctl);
X    tcp_Abort(&ftp_data);
X}
X
X
Xftp_application()
X{
X    char *s;
X    char *dp;
X    int i;
X
X    i = -1;
X    if ( isina() ) {
X        i = busyina() & 0177;
X#ifdef DEBUG
X        if ( i == ('D' & 037) ) SysBug("Pause to DDT");
X#endif
X        if ( i == ('C' & 037) ) {
X            printf("Closing...\n");
X            tcp_Close(&ftp_ctl);
X        }
X    }
X
X    switch (ftp_rcvState) {
X      case ftp_StateGETCMD:
X getcmd:if ( i != -1 ) {
X            ftp_outbuf[ftp_outbuflen] = 0;
X            switch (i) {
X                case 'H' & 037:
X                case 0177:
X                    if ( ftp_outbuflen > 0 ) {
X                        ftp_outbuflen--;
X                        printf("\010 \010");
X                    }
X                    break;
X
X                case 'R' & 037:
X                    if ( ftp_echoMode )
X                        printf("\nFtpCmd> %s", ftp_outbuf);
X                    break;
X
X                case 033:
X                    ftp_echoMode = ! ftp_echoMode;
X                    break;
X
X                case '\r':
X                case '\n':
X                    busyouta('\n');
X                    dp = &ftp_outbuf[ftp_outbuflen];
X                    goto docmd;
X
X                default:
X                    if ( i >= ' ' && ftp_outbuflen < sizeof ftp_outbuf ) {
X                        ftp_outbuf[ftp_outbuflen++] = i;
X                        if ( ftp_echoMode ) busyouta(i);
X                    }
X            }
X        }
X        break;
X
X      case ftp_StateIDLE:
X        if ( ftp_scriptline < 0 ) {
X            ftp_rcvState = ftp_StateGETCMD;
X            ftp_echoMode = true;
X            ftp_outbuflen = 0;
X            printf("FtpCmd> ");
X            goto getcmd;
X        }
X        s = ftp_script[ftp_scriptline];
X        if ( s == NIL )
X            break;
X        ftp_scriptline++;
X        printf("%s\n", s);
X        dp = ftp_outbuf;
X        while ( *dp++ = *s++ ) ;
X        dp--;
X docmd: *dp++ = '\r';
X        *dp++ = '\n';
X        ftp_outbuflen = dp - ftp_outbuf;
X        ftp_outbufix = 0;
X        ftp_rcvState = ftp_StateINCOMMAND;
X        /* fall through */
X    case ftp_StateINCOMMAND:
X        i = ftp_outbuflen - ftp_outbufix;
X        if ( i > 0 ) {
X            i = tcp_Write(&ftp_ctl, &ftp_outbuf[ftp_outbufix], i);
X            ftp_outbufix += i;
X            tcp_Flush(&ftp_ctl);
X        }
X        /* fall through */
X    case ftp_StateRCVRESP:
X        break;
X    }
X
X}
X
Xftp(host, fn, dataHandler)
X    in_HwAddress host;
X    char *fn;
X    procref dataHandler;
X{
X    word port;
X    char filecmd[80];
X
X    port = (sed_lclEthAddr[2] + clock_ValueRough()) | 0x8000;
X
X    if ( fn ) {
X        /* set up the script for this session */
X        ftp_script[0] = "user foo";
X        ftp_script[1] = "pass foo";
X        ftp_script[2] = "type i";
X        sprintf(filecmd, "retr %s", fn);
X        ftp_script[3] = filecmd;
X        ftp_script[4] = "quit";
X        ftp_script[5] = 0;
X        ftp_scriptline = 0;
X    } else {
X        ftp_scriptline = -1;        /* interactive mode */
X        ftp_echoMode = true;
X    }
X
X    /* set up state variables */
X    ftp_rcvState = ftp_StateRCVRESP;
X    ftp_cmdbufi = 0;
X    tcp_Listen(&ftp_data, port, dataHandler, 0);
X    tcp_Open(&ftp_ctl, port, host, 21, ftp_ctlHandler);
X    tcp(ftp_application);
X}
END-of-tinyftp.c
echo file: tinytcp.c
sed 's/^X//' >tinytcp.c << 'END-of-tinytcp.c'
X/*
X * tinytcp.c - Tiny Implementation of the Transmission Control Protocol
X *
X * Written March 28, 1986 by Geoffrey Cooper, IMAGEN Corporation.
X *
X * This code is a small implementation of the TCP and IP protocols, suitable
X * for burning into ROM.  The implementation is bare-bones and represents
X * two days' coding efforts.  A timer and an ethernet board are assumed.  The
X * implementation is based on busy-waiting, but the tcp_handler procedure
X * could easily be integrated into an interrupt driven scheme.
X *
X * IP routing is accomplished on active opens by broadcasting the tcp SYN
X * packet when ARP mapping fails.  If anyone answers, the ethernet address
X * used is saved for future use.  This also allows IP routing on incoming
X * connections.
X * 
X * The TCP does not implement urgent pointers (easy to add), and discards
X * segments that are received out of order.  It ignores the received window
X * and always offers a fixed window size on input (i.e., it is not flow
X * controlled).
X *
X * Special care is taken to access the ethernet buffers only in word
X * mode.  This is to support boards that only allow word accesses.
X *
X * Copyright (C) 1986, IMAGEN Corporation
X *  "This code may be duplicated in whole or in part provided that [1] there
X *   is no commercial gain involved in the duplication, and [2] that this
X *   copyright notice is preserved on all copies.  Any other duplication
X *   requires written notice of the author."
X */
X
X#include "tinytcp.h"
X
X/*
X * Local IP address
X */
Xin_HwAddress sin_lclINAddr;
X
X/*
X * IP identification numbers
X */
Xint tcp_id;
X
Xtcp_Socket *tcp_allsocs;
X
X/* Timer definitions */
X#define tcp_RETRANSMITTIME 1000     /* interval at which retransmitter is called */
X#define tcp_LONGTIMEOUT 31000       /* timeout for opens */
X#define tcp_TIMEOUT 10000           /* timeout during a connection */
X
X#ifdef DEBUG
X/* 
X * Primitive logging facility
X */
X#define tcp_LOGPACKETS 1        /* log packet headers */
Xword tcp_logState;
X#endif
X
X/*
X * Initialize the tcp implementation
X */
Xtcp_Init()
X{
X    extern eth_HwAddress sed_lclEthAddr;
X
X    /* initialize ethernet interface */
X    sed_Init();
X
X    tcp_allsocs = NIL;
X#ifdef DEBUG
X    tcp_logState = 0;
X#endif
X    tcp_id = 0;
X
X    /* hack - assume the network number */
X    sin_lclINAddr = 0x7d000000 + (*((longword *)&sed_lclEthAddr[1]) & 0xFFFFFF);
X}
X
X/*
X * Actively open a TCP connection to a particular destination.
X */
Xtcp_Open(s, lport, ina, port, datahandler)
X    tcp_Socket *s;
X    in_HwAddress ina;
X    word lport, port;
X    procref datahandler;
X{
X    extern eth_HwAddress sed_ethBcastAddr;
X
X    s->state = tcp_StateSYNSENT;
X    s->timeout = tcp_LONGTIMEOUT;
X    if ( lport == 0 ) lport = clock_ValueRough();
X    s->myport = lport;
X    if ( ! sar_MapIn2Eth(ina, &s->hisethaddr[0]) ) {
X        printf("tcp_Open of 0x%x: defaulting ethernet address to broadcast\n", ina);
X        Move(&sed_ethBcastAddr[0], &s->hisethaddr[0], sizeof(eth_HwAddress));
X    }
X    s->hisaddr = ina;
X    s->hisport = port;
X    s->seqnum = 0;
X    s->dataSize = 0;
X    s->flags = tcp_FlagSYN;
X    s->unhappy = true;
X    s->dataHandler = datahandler;
X    s->next = tcp_allsocs;
X    tcp_allsocs = s;
X    tcp_Send(s);
X}
X
X/*
X * Passive open: listen for a connection on a particular port
X */
Xtcp_Listen(s, port, datahandler, timeout)
X    tcp_Socket *s;
X    word port;
X    procref datahandler;
X{
X    s->state = tcp_StateLISTEN;
X    if ( timeout == 0 ) s->timeout = 0x7ffffff; /* forever... */
X    else s->timeout = timeout;
X    s->myport = port;
X    s->hisport = 0;
X    s->seqnum = 0;
X    s->dataSize = 0;
X    s->flags = 0;
X    s->unhappy = 0;
X    s->dataHandler = datahandler;
X    s->next = tcp_allsocs;
X    tcp_allsocs = s;
X}
X
X/*
X * Send a FIN on a particular port -- only works if it is open
X */
Xtcp_Close(s)
X    tcp_Socket *s;
X{
X    if ( s->state == tcp_StateESTAB || s->state == tcp_StateSYNREC ) {
X        s->flags = tcp_FlagACK | tcp_FlagFIN;
X        s->state = tcp_StateFINWT1;
X        s->unhappy = true;
X    }
X}
X
X/*
X * Abort a tcp connection
X */
Xtcp_Abort(s)
X    tcp_Socket *s;
X{
X    if ( s->state != tcp_StateLISTEN && s->state != tcp_StateCLOSED ) {
X        s->flags = tcp_FlagRST | tcp_FlagACK;
X        tcp_Send(s);
X    }
X    s->unhappy = 0;
X    s->dataSize = 0;
X    s->state = tcp_StateCLOSED;
X    s->dataHandler(s, 0, -1);
X    tcp_Unthread(s);
X}
X
X/*
X * Retransmitter - called periodically to perform tcp retransmissions
X */
Xtcp_Retransmitter()
X{
X    tcp_Socket *s;
X    BOOL x;
X
X    for ( s = tcp_allsocs; s; s = s->next ) {
X        x = false;
X        if ( s->dataSize > 0 || s->unhappy ) {
X            tcp_Send(s);
X            x = true;
X        }
X        if ( x || s->state != tcp_StateESTAB )
X            s->timeout -= tcp_RETRANSMITTIME;
X        if ( s->timeout <= 0 ) {
X            if ( s->state == tcp_StateTIMEWT ) {
X                printf("Closed.    \n");
X                s->state = tcp_StateCLOSED;
X                s->dataHandler(s, 0, 0);
X                tcp_Unthread(s);
X            } else {
X                printf("Timeout, aborting\n");
X                tcp_Abort(s);
X            }
X        }
X    }
X}
X
X/*
X * Unthread a socket from the socket list, if it's there 
X */
Xtcp_Unthread(ds)
X    tcp_Socket *ds;
X{
X    tcp_Socket *s, **sp;
X
X    sp = &tcp_allsocs;
X    for (;;) {
X        s = *sp;
X        if ( s == ds ) {
X            *sp = s->next;
X            break;
X        }
X        if ( s == NIL ) break;
X        sp = &s->next;
X    }
X}
X
X/*
X * busy-wait loop for tcp.  Also calls an "application proc"
X */
Xtcp(application)
X    procref application;
X{
X    in_Header *ip;
X    longword timeout, start;
X    int x;
X
X    sed_Receive(0);
X
X    timeout = 0;
X    while ( tcp_allsocs ) {
X        start = clock_ValueRough();
X        ip = sed_IsPacket();
X        if ( ip == NIL ) {
X            if ( clock_ValueRough() > timeout ) {
X                tcp_Retransmitter();
X                timeout = clock_ValueRough() + tcp_RETRANSMITTIME;
X            }
X
X            application();
X
X            continue;
X        }
X
X        if ( sed_CheckPacket(ip, 0x806) == 1 ) {
X            /* do arp */
X            sar_CheckPacket(ip);
X
X        } else if ( sed_CheckPacket(ip, 0x800) == 1 ) {
X            /* do IP */
X            if ( ip->destination == sin_lclINAddr &&
X                 in_GetProtocol(ip) == 6 &&
X                 checksum(ip, in_GetHdrlenBytes(ip)) == 0xFFFF ) {
X                tcp_Handler(ip);
X            }
X        }
X        /* recycle buffer */
X        sed_Receive(ip);
X
X        x = clock_ValueRough() - start;
X        timeout -= x;
X    }
X
X    return ( 1 );
X}
X
X/*
X * Write data to a connection.
X * Returns number of bytes written, == 0 when connection is not in
X * established state.
X */
Xtcp_Write(s, dp, len)
X    tcp_Socket *s;
X    byte *dp;
X    int len;
X{
X    int x;
X
X    if ( s->state != tcp_StateESTAB ) len = 0;
X    if ( len > (x = tcp_MaxData - s->dataSize) ) len = x;
X    if ( len > 0 ) {
X        Move(dp, &s->data[s->dataSize], len);
X        s->dataSize += len;
X        tcp_Flush(s);
X    }
X
X    return ( len );
X}
X
X/*
X * Send pending data
X */
Xtcp_Flush(s)
X    tcp_Socket *s;
X{
X    if ( s->dataSize > 0 ) {
X        s->flags |= tcp_FlagPUSH;
X        tcp_Send(s);
X    }
X}
X
X/*
X * Handler for incoming packets.
X */
Xtcp_Handler(ip)
X    in_Header *ip;
X{
X    tcp_Header *tp;
X    tcp_PseudoHeader ph;
X    int len;
X    byte *dp;
X    int x, diff;
X    tcp_Socket *s;
X    word flags;
X
X    len = in_GetHdrlenBytes(ip);
X    tp = (tcp_Header *)((byte *)ip + len);
X    len = ip->length - len;
X
X    /* demux to active sockets */
X    for ( s = tcp_allsocs; s; s = s->next )
X        if ( s->hisport != 0 &&
X             tp->dstPort == s->myport &&
X             tp->srcPort == s->hisport &&
X             ip->source == s->hisaddr ) break;
X    if ( s == NIL ) {
X        /* demux to passive sockets */
X        for ( s = tcp_allsocs; s; s = s->next )
X            if ( s->hisport == 0 && tp->dstPort == s->myport ) break;
X    }
X    if ( s == NIL ) {
X#ifdef DEBUG
X        if ( tcp_logState & tcp_LOGPACKETS ) tcp_DumpHeader(ip, tp, "Discarding");
X#endif
X        return;
X    }
X
X#ifdef DEBUG
X    if ( tcp_logState & tcp_LOGPACKETS )
X        tcp_DumpHeader(ip, tp, "Received");
X#endif
X
X    /* save his ethernet address */
X    MoveW(&((((eth_Header *)ip) - 1)->source[0]), &s->hisethaddr[0], sizeof(eth_HwAddress));
X
X    ph.src = ip->source;
X    ph.dst = ip->destination;
X    ph.mbz = 0;
X    ph.protocol = 6;
X    ph.length = len;
X    ph.checksum = checksum(tp, len);
X    if ( checksum(&ph, sizeof ph) != 0xffff )
X         printf("bad tcp checksum, received anyway\n");
X
X    flags = tp->flags;
X    if ( flags & tcp_FlagRST ) {
X        printf("connection reset\n");
X        s->state = tcp_StateCLOSED;
X        s->dataHandler(s, 0, -1);
X        tcp_Unthread(s);
X        return;
X    }
X
X    switch ( s->state ) {
X
X    case tcp_StateLISTEN:
X        if ( flags & tcp_FlagSYN ) {
X            s->acknum = tp->seqnum + 1;
X            s->hisport = tp->srcPort;
X            s->hisaddr = ip->source;
X            s->flags = tcp_FlagSYN | tcp_FlagACK;
X            tcp_Send(s);
X            s->state = tcp_StateSYNREC;
X            s->unhappy = true;
X            s->timeout = tcp_TIMEOUT;
X            printf("Syn from 0x%x#%d (seq 0x%x)\n", s->hisaddr, s->hisport, tp->seqnum);
X        }
X        break;
X
X    case tcp_StateSYNSENT:
X        if ( flags & tcp_FlagSYN ) {
X            s->acknum++;
X            s->flags = tcp_FlagACK;
X            s->timeout = tcp_TIMEOUT;
X            if ( (flags & tcp_FlagACK) && tp->acknum == (s->seqnum + 1) ) {
X                printf("Open\n");
X                s->state = tcp_StateESTAB;
X                s->seqnum++;
X                s->acknum = tp->seqnum + 1;
X                s->unhappy = false;
X            } else {
X                s->state = tcp_StateSYNREC;
X            }
X        }
X        break;
X
X    case tcp_StateSYNREC:
X        if ( flags & tcp_FlagSYN ) {
X            s->flags = tcp_FlagSYN | tcp_FlagACK;
X            tcp_Send(s);
X            s->timeout = tcp_TIMEOUT;
X            printf(" retransmit of original syn\n");
X        }
X        if ( (flags & tcp_FlagACK) && tp->acknum == (s->seqnum + 1) ) {
X            s->flags = tcp_FlagACK;
X            tcp_Send(s);
X            s->seqnum++;
X            s->unhappy = false;
X            s->state = tcp_StateESTAB;
X            s->timeout = tcp_TIMEOUT;
X            printf("Synack received - connection established\n");
X        }
X        break;
X
X    case tcp_StateESTAB:
X        if ( (flags & tcp_FlagACK) == 0 ) return;
X        /* process ack value in packet */
X        diff = tp->acknum - s->seqnum;
X        if ( diff > 0 ) {
X            Move(&s->data[diff], &s->data[0], diff);
X            s->dataSize -= diff;
X            s->seqnum += diff;
X        }
X        s->flags = tcp_FlagACK;
X        tcp_ProcessData(s, tp, len);
X        break;
X
X    case tcp_StateFINWT1:
X        if ( (flags & tcp_FlagACK) == 0 ) return;
X        diff = tp->acknum - s->seqnum - 1;
X        s->flags = tcp_FlagACK | tcp_FlagFIN;
X        if ( diff == 0 ) {
X            s->state = tcp_StateFINWT2;
X            s->flags = tcp_FlagACK;
X            printf("finack received.\n");
X        }
X        tcp_ProcessData(s, tp, len);
X        break;
X
X    case tcp_StateFINWT2:
X        s->flags = tcp_FlagACK;
X        tcp_ProcessData(s, tp, len);
X        break;
X
X    case tcp_StateCLOSING:
X        if ( tp->acknum == (s->seqnum + 1) ) {
X            s->state = tcp_StateTIMEWT;
X            s->timeout = tcp_TIMEOUT;
X        }
X        break;
X
X    case tcp_StateLASTACK:
X        if ( tp->acknum == (s->seqnum + 1) ) {
X            s->state = tcp_StateCLOSED;
X            s->unhappy = false;
X            s->dataSize = 0;
X            s->dataHandler(s, 0, 0);
X            tcp_Unthread(s);
X            printf("Closed.    \n");
X        } else {
X            s->flags = tcp_FlagACK | tcp_FlagFIN;
X            tcp_Send(s);
X            s->timeout = tcp_TIMEOUT;
X            printf("retransmitting FIN\n");
X        }
X        break;
X
X    case tcp_StateTIMEWT:
X        s->flags = tcp_FlagACK;
X        tcp_Send(s);
X    }
X}
X
X/*
X * Process the data in an incoming packet.
X * Called from all states where incoming data can be received: established,
X * fin-wait-1, fin-wait-2
X */
Xtcp_ProcessData(s, tp, len)
X    tcp_Socket *s;
X    tcp_Header *tp;
X    int len;
X{
X    int diff, x;
X    word flags;
X    byte *dp;
X
X    flags = tp->flags;
X    diff = s->acknum - tp->seqnum;
X    if ( flags & tcp_FlagSYN ) diff--;
X    x = tcp_GetDataOffset(tp) << 2;
X    dp = (byte *)tp + x;
X    len -= x;
X    if ( diff >= 0 ) {
X        dp += diff;
X        len -= diff;
X        s->acknum += len;
X        s->dataHandler(s, dp, len);
X        if ( flags & tcp_FlagFIN ) {
X            s->acknum++;
X#ifdef DEBUG
X            printf("consumed fin.\n");
X#endif
X            switch(s->state) {
X              case tcp_StateESTAB:
X                /* note: skip state CLOSEWT by automatically closing conn */
X                x = tcp_StateLASTACK;
X                s->flags |= tcp_FlagFIN;
X                s->unhappy = true;
X#ifdef DEBUG
X                printf("sending fin.\n");
X#endif
X                break;
X              case tcp_StateFINWT1:
X                x = tcp_StateCLOSING;
X                break;
X              case tcp_StateFINWT2:
X                x = tcp_StateTIMEWT;
X                break;
X            }
X            s->state = x;
X        }
X    }
X    s->timeout = tcp_TIMEOUT;
X    tcp_Send(s);
X}
X
X/*
X * Format and send an outgoing segment
X */
Xtcp_Send(s)
X    tcp_Socket *s;
X{
X    tcp_PseudoHeader ph;
X    struct _pkt {
X        in_Header in;
X        tcp_Header tcp;
X        longword maxsegopt;
X    } *pkt;
X    byte *dp;
X
X    pkt = (struct _pkt *)sed_FormatPacket(&s->hisethaddr[0], 0x800);
X    dp = &pkt->maxsegopt;
X
X    pkt->in.length = sizeof(in_Header) + sizeof(tcp_Header) + s->dataSize;
X
X    /* tcp header */
X    pkt->tcp.srcPort = s->myport;
X    pkt->tcp.dstPort = s->hisport;
X    pkt->tcp.seqnum = s->seqnum;
X    pkt->tcp.acknum = s->acknum;
X    pkt->tcp.window = 1024;
X    pkt->tcp.flags = s->flags | 0x5000;
X    pkt->tcp.checksum = 0;
X    pkt->tcp.urgentPointer = 0;
X    if ( s->flags & tcp_FlagSYN ) {
X        pkt->tcp.flags += 0x1000;
X        pkt->in.length += 4;
X        pkt->maxsegopt = 0x02040578; /* 1400 bytes */
X        dp += 4;
X    }
X    MoveW(s->data, dp, s->dataSize);
X
X    /* internet header */
X    pkt->in.vht = 0x4500;   /* version 4, hdrlen 5, tos 0 */
X    pkt->in.identification = tcp_id++;
X    pkt->in.frag = 0;
X    pkt->in.ttlProtocol = (250<<8) + 6;
X    pkt->in.checksum = 0;
X    pkt->in.source = sin_lclINAddr;
X    pkt->in.destination = s->hisaddr;
X    pkt->in.checksum = ~checksum(&pkt->in, sizeof(in_Header));
X
X    /* compute tcp checksum */
X    ph.src = pkt->in.source;
X    ph.dst = pkt->in.destination;
X    ph.mbz = 0;
X    ph.protocol = 6;
X    ph.length = pkt->in.length - sizeof(in_Header);
X    ph.checksum = checksum(&pkt->tcp, ph.length);
X    pkt->tcp.checksum = ~checksum(&ph, sizeof ph);
X
X#ifdef DEBUG
X    if ( tcp_logState & tcp_LOGPACKETS )
X        tcp_DumpHeader(&pkt->in, &pkt->tcp, "Sending");
X#endif
X
X    sed_Send(pkt->in.length);
X}
X
X/*
X * Do a one's complement checksum
X */
Xchecksum(dp, length)
X    word *dp;
X    int length;
X{
X    int len;
X    longword sum;
X
X    len = length >> 1;
X    sum = 0;
X    while ( len-- > 0 ) sum += *dp++;
X    if ( length & 1 ) sum += (*dp & 0xFF00);
X    sum = (sum & 0xFFFF) + ((sum >> 16) & 0xFFFF);
X    sum = (sum & 0xFFFF) + ((sum >> 16) & 0xFFFF);
X
X    return ( sum );
X}
X
X/*
X * Dump the tcp protocol header of a packet
X */
Xtcp_DumpHeader( ip, tp, mesg )
X    in_Header *ip;
X    char *mesg;
X{
X    register tcp_Header *tp = (tcp_Header *)((byte *)ip + in_GetHdrlenBytes(ip));
X    static char *flags[] = { "FIN", "SYN", "RST", "PUSH", "ACK", "URG" };
X    int len;
X    word f;
X
X    len =  ip->length - ((tcp_GetDataOffset(tp) + in_GetHdrlen(ip)) << 2);
X    printf("TCP: %s packet:\nS: %x; D: %x; SN=%x ACK=%x W=%d DLen=%d\n",
X           mesg, tp->srcPort, tp->dstPort, tp->seqnum, tp->acknum,
X           tp->window, len);
X    printf("DO=%d, C=%x U=%d",
X           tcp_GetDataOffset(tp), tp->checksum, tp->urgentPointer);
X    /* output flags */
X    f = tp->flags;
X    for ( len = 0; len < 6; len++ )
X        if ( f & (1 << len) ) printf(" %s", flags[len]);
X    printf("\n");
X}
X
X/*
X * Move bytes from hither to yon
X */
XMove( src, dest, numbytes )
X    register byte *src, *dest;
X    register numbytes;
X{
X    if ( numbytes <= 0 ) return;
X    if ( src < dest ) {
X        src += numbytes;
X        dest += numbytes;
X        do {
X            *--dest = *--src;
X        } while ( --numbytes > 0 );
X    } else
X        do {
X             *dest++ = *src++;
X        } while ( --numbytes > 0 );
X}
END-of-tinytcp.c
echo file: tinytcp.h
sed 's/^X//' >tinytcp.h << 'END-of-tinytcp.h'
X/*
X * tinytcp.h - header file for tinytcp.c
X *
X * Copyright (C) 1986, IMAGEN Corporation
X *  "This code may be duplicated in whole or in part provided that [1] there
X *   is no commercial gain involved in the duplication, and [2] that this
X *   copyright notice is preserved on all copies.  Any other duplication
X *   requires written notice of the author."
X *
X * Note: the structures herein must guarantee that the
X *       code only performs word fetches, since the
X *       imagenether card doesn't accept byte accesses.
X */
X
X#define TRUE        1
X#define true        1
X#define FALSE       0
X#define false       0
X#define NULL        0               /* An empty value */
X#define NIL         0               /* The distinguished empty pointer */
X
X/* Useful type definitions */
Xtypedef int (*procref)();
Xtypedef short BOOL;                  /* boolean type */
X
X/* Canonically-sized data */
Xtypedef unsigned long longword;     /* 32 bits */
Xtypedef unsigned short word;        /* 16 bits */
Xtypedef unsigned char byte;         /*  8 bits */
Xtypedef byte octet;                 /*  8 bits, for TCP */
X
X#ifdef DDT
Xextern longword MsecClock();
X#define clock_ValueRough() MsecClock()
X#else
Xextern longword clock_MS;
X#define clock_ValueRough() clock_MS
X#endif
X
X/* protocol address definitions */
Xtypedef longword in_HwAddress;
Xtypedef word eth_HwAddress[3];
X
X/* The Ethernet header */
Xtypedef struct {
X    eth_HwAddress   destination;
X    eth_HwAddress   source;
X    word            type;
X} eth_Header;
X
X/* The Internet Header: */
Xtypedef struct {
X    word            vht;    /* version, hdrlen, tos */
X    word            length;
X    word            identification;
X    word            frag;
X    word            ttlProtocol;
X    word            checksum;
X    in_HwAddress    source;
X    in_HwAddress    destination;
X} in_Header;
X#define in_GetVersion(ip) (((ip)->vht >> 12) & 0xf)
X#define in_GetHdrlen(ip)  (((ip)->vht >> 8) & 0xf)
X#define in_GetHdrlenBytes(ip)  (((ip)->vht >> 6) & 0x3c)
X#define in_GetTos(ip)      ((ip)->vht & 0xff)
X
X#define in_GetTTL(ip)      ((ip)->ttlProtocol >> 8)
X#define in_GetProtocol(ip) ((ip)->ttlProtocol & 0xff)
X
X
Xtypedef struct {
X    word            srcPort;
X    word            dstPort;
X    longword        seqnum;
X    longword        acknum;
X    word            flags;
X    word            window;
X    word            checksum;
X    word            urgentPointer;
X} tcp_Header;
X
X
X#define tcp_FlagFIN     0x0001
X#define tcp_FlagSYN     0x0002
X#define tcp_FlagRST     0x0004
X#define tcp_FlagPUSH    0x0008
X#define tcp_FlagACK     0x0010
X#define tcp_FlagURG     0x0020
X#define tcp_FlagDO      0xF000
X#define tcp_GetDataOffset(tp) ((tp)->flags >> 12)
X
X/* The TCP/UDP Pseudo Header */
Xtypedef struct {
X    in_HwAddress    src;
X    in_HwAddress    dst;
X    octet           mbz;
X    octet           protocol;
X    word            length;
X    word            checksum;
X} tcp_PseudoHeader;
X
X/*
X * TCP states, from tcp manual.
X * Note: close-wait state is bypassed by automatically closing a connection
X *       when a FIN is received.  This is easy to undo.
X */
X#define tcp_StateLISTEN  0      /* listening for connection */
X#define tcp_StateSYNSENT 1      /* syn sent, active open */
X#define tcp_StateSYNREC  2      /* syn received, synack+syn sent. */
X#define tcp_StateESTAB   3      /* established */
X#define tcp_StateFINWT1  4      /* sent FIN */
X#define tcp_StateFINWT2  5      /* sent FIN, received FINACK */
X/*#define tcp_StateCLOSEWT 6    /* received FIN waiting for close */
X#define tcp_StateCLOSING 6      /* sent FIN, received FIN (waiting for FINACK) */
X#define tcp_StateLASTACK 7      /* fin received, finack+fin sent */
X#define tcp_StateTIMEWT  8      /* dally after sending final FINACK */
X#define tcp_StateCLOSED  9      /* finack received */
X
X/*
X * TCP Socket definition
X */
X#define tcp_MaxData 32              /* maximum bytes to buffer on output */
X
Xtypedef struct _tcp_socket {
X    struct _tcp_socket *next;
X    short           state;          /* connection state */
X    procref         dataHandler;    /* called with incoming data */
X    eth_HwAddress   hisethaddr;     /* ethernet address of peer */
X    in_HwAddress    hisaddr;        /* internet address of peer */
X    word            myport, hisport;/* tcp ports for this connection */
X    longword        acknum, seqnum; /* data ack'd and sequence num */
X    int             timeout;        /* timeout, in milliseconds */
X    BOOL            unhappy;        /* flag, indicates retransmitting segt's */
X    word            flags;          /* tcp flags word for last packet sent */
X    short           dataSize;       /* number of bytes of data to send */
X    byte            data[tcp_MaxData]; /* data to send */
X} tcp_Socket;
X
Xextern eth_HwAddress sed_lclEthAddr;
Xextern eth_HwAddress sed_ethBcastAddr;
Xextern in_HwAddress  sin_lclINAddr;
X
X/*
X * ARP definitions
X */
X#define arp_TypeEther  1        /* ARP type of Ethernet address *
X
X/* harp op codes */
X#define ARP_REQUEST 1
X#define ARP_REPLY   2
X
X/*
X * Arp header
X */
Xtypedef struct {
X    word            hwType;
X    word            protType;
X    word            hwProtAddrLen;  /* hw and prot addr len */
X    word            opcode;
X    eth_HwAddress   srcEthAddr;
X    in_HwAddress    srcIPAddr;
X    eth_HwAddress   dstEthAddr;
X    in_HwAddress    dstIPAddr;
X} arp_Header;
X
X/*
X * Ethernet interface:
X *   sed_WaitPacket(0) => ptr to packet (beyond eth header)
X *                          or NIL if no packet ready.
X *   sed_Receive(ptr) - reenables receive on input buffer
X *   sed_FormatPacket(&ethdest, ethtype) => ptr to packet buffer
X *   sed_Send(packet_length) - send the buffer last formatted.
X */
Xbyte *sed_IsPacket(), *sed_FormatPacket();
END-of-tinytcp.h
exit