busybox

/* vi: set sw=4 ts=4: */

/*

 * telnet implementation for busybox

 *

 * Author: Tomi Ollila <too@iki.fi>

 * Copyright (C) 1994-2000 by Tomi Ollila

 *

 * Created: Thu Apr  7 13:29:41 1994 too

 * Last modified: Fri Jun  9 14:34:24 2000 too

 *

 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.

 *

 * HISTORY

 * Revision 3.1  1994/04/17  11:31:54  too

 * initial revision

 * Modified 2000/06/13 for inclusion into BusyBox by Erik Andersen <andersen@codepoet.org>

 * Modified 2001/05/07 to add ability to pass TTYPE to remote host by Jim McQuillan

 * <jam@ltsp.org>

 * Modified 2004/02/11 to add ability to pass the USER variable to remote host

 * by Fernando Silveira <swrh@gmx.net>

 *

 */

​

#include <termios.h>

#include <arpa/telnet.h>

#include <netinet/in.h>

#include "libbb.h"

​

#ifdef DOTRACE

#define TRACE(x, y) do { if (x) printf y; } while (0)

#else

#define TRACE(x, y)

#endif

​

enum {

    DATABUFSIZE = 128,

    IACBUFSIZE  = 128,

​

    CHM_TRY = 0,

    CHM_ON = 1,

    CHM_OFF = 2,

​

    UF_ECHO = 0x01,

    UF_SGA = 0x02,

​

    TS_0 = 1,

    TS_IAC = 2,

    TS_OPT = 3,

    TS_SUB1 = 4,

    TS_SUB2 = 5,

};

​

typedef unsigned char byte;

​

enum { netfd = 3 };

​

struct globals {

    int iaclen; /* could even use byte, but it's a loss on x86 */

    byte    telstate; /* telnet negotiation state from network input */

    byte    telwish;  /* DO, DONT, WILL, WONT */

    byte    charmode;

    byte    telflags;

    byte    do_termios;