text: /*
   * Copyright (c) 1989, 1993
   *	The Regents of the University of California.  All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. All advertising materials mentioning features or use of this software
   *    must display the following acknowledgement:
   *	This product includes software developed by the University of
   *	California, Berkeley and its contributors.
   * 4. Neither the name of the University nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   */
  
  #ifndef lint
  #if 0
  static char sccsid[] = "@(#)utility.c	8.2 (Berkeley) 12/15/93";
  #endif
  static const char rcsid[] =
  	"$Id: utility.c,v 1.5.2.4 1998/05/03 16:33:34 steve Exp $";
  #endif /* not lint */
  
  #ifdef __FreeBSD__
  #include <locale.h>
  #include <sys/utsname.h>
  #endif
  #define PRINTOPTIONS
  #include "telnetd.h"
  
  /*
   * utility functions performing io related tasks
   */
  
  /*
   * ttloop
   *
   *	A small subroutine to flush the network output buffer, get some data
   * from the network, and pass it through the telnet state machine.  We
   * also flush the pty input buffer (by dropping its data) if it becomes
   * too full.
   */
  
      void
  ttloop()
  {
      void netflush();
  
      DIAG(TD_REPORT, {sprintf(nfrontp, "td: ttloop\r\n");
  		     nfrontp += strlen(nfrontp);});
      if (nfrontp-nbackp) {
  	netflush();
      }
      ncc = read(net, netibuf, sizeof netibuf);
      if (ncc < 0) {
  	syslog(LOG_INFO, "ttloop:  read: %m");
  	exit(1);
      } else if (ncc == 0) {
  	syslog(LOG_INFO, "ttloop:  peer died: %m");
  	exit(1);
      }
      DIAG(TD_REPORT, {sprintf(nfrontp, "td: ttloop read %d chars\r\n", ncc);
  		     nfrontp += strlen(nfrontp);});
      netip = netibuf;
      telrcv();			/* state machine */
      if (ncc > 0) {
  	pfrontp = pbackp = ptyobuf;
  	telrcv();
      }
  }  /* end of ttloop */
  
  /*
   * Check a descriptor to see if out of band data exists on it.
   */
      int
  stilloob(s)
      int	s;		/* socket number */
  {
      static struct timeval timeout = { 0 };
      fd_set	excepts;
      int value;
  
      do {
  	FD_ZERO(&excepts);
  	FD_SET(s, &excepts);
  	memset((char *)&timeout, 0, sizeof timeout);
  	value = select(s+1, (fd_set *)0, (fd_set *)0, &excepts, &timeout);
      } while ((value == -1) && (errno == EINTR));
  
      if (value < 0) {
  	fatalperror(pty, "select");
      }
      if (FD_ISSET(s, &excepts)) {
  	return 1;
      } else {
  	return 0;
      }
  }
  
  	void
  ptyflush()
  {
  	int n;
  
  	if ((n = pfrontp - pbackp) > 0) {
  		DIAG((TD_REPORT | TD_PTYDATA),
  			{ sprintf(nfrontp, "td: ptyflush %d chars\r\n", n);
  			  nfrontp += strlen(nfrontp); });
  		DIAG(TD_PTYDATA, printdata("pd", pbackp, n));
  		n = write(pty, pbackp, n);
  	}
  	if (n < 0) {
  		if (errno == EWOULDBLOCK || errno == EINTR)
  			return;
  		cleanup(0);
  	}
  	pbackp += n;
  	if (pbackp == pfrontp)
  		pbackp = pfrontp = ptyobuf;
  }
  
  /*
   * nextitem()
   *
   *	Return the address of the next "item" in the TELNET data
   * stream.  This will be the address of the next character if
   * the current address is a user data character, or it will
   * be the address of the character following the TELNET command
   * if the current address is a TELNET IAC ("I Am a Command")
   * character.
   */
      char *
  nextitem(current)
      char	*current;
  {
      if ((*current&0xff) != IAC) {
  	return current+1;
      }
      switch (*(current+1)&0xff) {
      case DO:
      case DONT:
      case WILL:
      case WONT:
  	return current+3;
      case SB:		/* loop forever looking for the SE */
  	{
  	    register char *look = current+2;
  
  	    for (;;) {
  		if ((*look++&0xff) == IAC) {
  		    if ((*look++&0xff) == SE) {
  			return look;
  		    }
  		}
  	    }
  	}
      default:
  	return current+2;
      }
  }  /* end of nextitem */
  
  
  /*
   * netclear()
   *
   *	We are about to do a TELNET SYNCH operation.  Clear
   * the path to the network.
   *
   *	Things are a bit tricky since we may have sent the first
   * byte or so of a previous TELNET command into the network.
   * So, we have to scan the network buffer from the beginning
   * until we are up to where we want to be.
   *
   *	A side effect of what we do, just to keep things
   * simple, is to clear the urgent data pointer.  The principal
   * caller should be setting the urgent data pointer AFTER calling
   * us in any case.
   */
      void
  netclear()
  {
      register char *thisitem, *next;
      char *good;
  #define	wewant(p)	((nfrontp > p) && ((*p&0xff) == IAC) && \
  				((*(p+1)&0xff) != EC) && ((*(p+1)&0xff) != EL))
  
      thisitem = netobuf;
  
      while ((next = nextitem(thisitem)) <= nbackp) {
  	thisitem = next;
      }
  
      /* Now, thisitem is first before/at boundary. */
  
      good = netobuf;	/* where the good bytes go */
  
      while (nfrontp > thisitem) {
  	if (wewant(thisitem)) {
  	    int length;
  
  	    next = thisitem;
  	    do {
  		next = nextitem(next);
  	    } while (wewant(next) && (nfrontp > next));
  	    length = next-thisitem;
  	    bcopy(thisitem, good, length);
  	    good += length;
  	    thisitem = next;
  	} else {
  	    thisitem = nextitem(thisitem);
  	}
      }
  
      nbackp = netobuf;
      nfrontp = good;		/* next byte to be sent */
      neturg = 0;
  }  /* end of netclear */
  
  /*
   *  netflush
   *		Send as much data as possible to the network,
   *	handling requests for urgent data.
   */
      void
  netflush()
  {
      int n;
      extern int not42;
  
      if ((n = nfrontp - nbackp) > 0) {
  	DIAG(TD_REPORT,
  	    { sprintf(nfrontp, "td: netflush %d chars\r\n", n);
  	      n += strlen(nfrontp);  /* get count first */
  	      nfrontp += strlen(nfrontp);  /* then move pointer */
  	    });
  	/*
  	 * if no urgent data, or if the other side appears to be an
  	 * old 4.2 client (and thus unable to survive TCP urgent data),
  	 * write the entire buffer in non-OOB mode.
  	 */
  	if ((neturg == 0) || (not42 == 0)) {
  	    n = write(net, nbackp, n);	/* normal write */
  	} else {
  	    n = neturg - nbackp;
  	    /*
  	     * In 4.2 (and 4.3) systems, there is some question about
  	     * what byte in a sendOOB operation is the "OOB" data.
  	     * To make ourselves compatible, we only send ONE byte
  	     * out of band, the one WE THINK should be OOB (though
  	     * we really have more the TCP philosophy of urgent data
  	     * rather than the Unix philosophy of OOB data).
  	     */
  	    if (n > 1) {
  		n = send(net, nbackp, n-1, 0);	/* send URGENT all by itself */
  	    } else {
  		n = send(net, nbackp, n, MSG_OOB);	/* URGENT data */
  	    }
  	}
      }
      if (n < 0) {
  	if (errno == EWOULDBLOCK || errno == EINTR)
  		return;
  	cleanup(0);
      }
      nbackp += n;
      if (nbackp >= neturg) {
  	neturg = 0;
      }
      if (nbackp == nfrontp) {
  	nbackp = nfrontp = netobuf;
      }
      return;
  }  /* end of netflush */
  
  
  /*
   * writenet
   *
   * Just a handy little function to write a bit of raw data to the net.
   * It will force a transmit of the buffer if necessary
   *
   * arguments
   *    ptr - A pointer to a character string to write
   *    len - How many bytes to write
   */
  	void
  writenet(ptr, len)
  	register unsigned char *ptr;
  	register int len;
  {
  	/* flush buffer if no room for new data) */
  	if ((&netobuf[BUFSIZ] - nfrontp) < len) {
  		/* if this fails, don't worry, buffer is a little big */
  		netflush();
  	}
  
  	bcopy(ptr, nfrontp, len);
  	nfrontp += len;
  
  }  /* end of writenet */
  
  
  /*
   * miscellaneous functions doing a variety of little jobs follow ...
   */
  
  
  	void
  fatal(f, msg)
  	int f;
  	char *msg;
  {
  	char buf[BUFSIZ];
  
  	(void) sprintf(buf, "telnetd: %s.\r\n", msg);
  	(void) write(f, buf, (int)strlen(buf));
  	sleep(1);	/*XXX*/
  	exit(1);
  }
  
  	void
  fatalperror(f, msg)
  	int f;
  	char *msg;
  {
  	char buf[BUFSIZ], *strerror();
  
  	(void) sprintf(buf, "%s: %s", msg, strerror(errno));
  	fatal(f, buf);
  }
  
  char editedhost[32];
  
  	void
  edithost(pat, host)
  	register char *pat;
  	register char *host;
  {
  	register char *res = editedhost;
  
  	if (!pat)
  		pat = "";
  	while (*pat) {
  		switch (*pat) {
  
  		case '#':
  			if (*host)
  				host++;
  			break;
  
  		case '@':
  			if (*host)
  				*res++ = *host++;
  			break;
  
  		default:
  			*res++ = *pat;
  			break;
  		}
  		if (res == &editedhost[sizeof editedhost - 1]) {
  			*res = '\0';
  			return;
  		}
  		pat++;
  	}
  	if (*host)
  		(void) strncpy(res, host,
  				sizeof editedhost - (res - editedhost) -1);
  	else
  		*res = '\0';
  	editedhost[sizeof editedhost - 1] = '\0';
  }
  
  static char *putlocation;
  
  	void
  putstr(s)
  	register char *s;
  {
  
  	while (*s)
  		putchr(*s++);
  }
  
  	void
  putchr(cc)
  	int cc;
  {
  	*putlocation++ = cc;
  }
  
  #ifdef __FreeBSD__
  static char fmtstr[] = { "%+" };
  #else
  /*
   * This is split on two lines so that SCCS will not see the M
   * between two % signs and expand it...
   */
  static char fmtstr[] = { "%l:%M\
  %P on %A, %d %B %Y" };
  #endif
  
  	void
  putf(cp, where)
  	register char *cp;
  	char *where;
  {
  	char *slash;
  	time_t t;
  	char db[100];
  #ifdef	STREAMSPTY
  	extern char *index();
  #else
  	extern char *rindex();
  #endif
  #ifdef __FreeBSD__
  	static struct utsname kerninfo;
  
  	if (!*kerninfo.sysname)
  		uname(&kerninfo);
  #endif
  
  	putlocation = where;
  
  	while (*cp) {
  		if (*cp =='\n') {
  			putstr("\r\n");
  			cp++;
  			continue;
  		} else if (*cp != '%') {
  			putchr(*cp++);
  			continue;
  		}
  		switch (*++cp) {
  
  		case 't':
  #ifdef	STREAMSPTY
  			/* names are like /dev/pts/2 -- we want pts/2 */
  			slash = index(line+1, '/');
  #else
  			slash = rindex(line, '/');
  #endif
  			if (slash == (char *) 0)
  				putstr(line);
  			else
  				putstr(&slash[1]);
  			break;
  
  		case 'h':
  			putstr(editedhost);
  			break;
  
  		case 'd':
  #ifdef __FreeBSD__
  			setlocale(LC_TIME, "");
  #endif
  			(void)time(&t);
  			(void)strftime(db, sizeof(db), fmtstr, localtime(&t));
  			putstr(db);
  			break;
  
  #ifdef __FreeBSD__
  		case 's':
  			putstr(kerninfo.sysname);
  			break;
  
  		case 'm':
  			putstr(kerninfo.machine);
  			break;
  
  		case 'r':
  			putstr(kerninfo.release);
  			break;
  
  		case 'v':
  			putstr(kerninfo.version);
  			break;
  #endif
  
  		case '%':
  			putchr('%');
  			break;
  		}
  		cp++;
  	}
  }
  
  #ifdef DIAGNOSTICS
  /*
   * Print telnet options and commands in plain text, if possible.
   */
  	void
  printoption(fmt, option)
  	register char *fmt;
  	register int option;
  {
  	if (TELOPT_OK(option))
  		sprintf(nfrontp, "%s %s\r\n", fmt, TELOPT(option));
  	else if (TELCMD_OK(option))
  		sprintf(nfrontp, "%s %s\r\n", fmt, TELCMD(option));
  	else
  		sprintf(nfrontp, "%s %d\r\n", fmt, option);
  	nfrontp += strlen(nfrontp);
  	return;
  }
  
      void
  printsub(direction, pointer, length)
      char		direction;	/* '<' or '>' */
      unsigned char	*pointer;	/* where suboption data sits */
      int			length;		/* length of suboption data */
  {
      register int i = 0;
  
          if (!(diagnostic & TD_OPTIONS))
  		return;
  
  	if (direction) {
  	    sprintf(nfrontp, "td: %s suboption ",
  					direction == '<' ? "recv" : "send");
  	    nfrontp += strlen(nfrontp);
  	    if (length >= 3) {
  		register int j;
  
  		i = pointer[length-2];
  		j = pointer[length-1];
  
  		if (i != IAC || j != SE) {
  		    sprintf(nfrontp, "(terminated by ");
  		    nfrontp += strlen(nfrontp);
  		    if (TELOPT_OK(i))
  			sprintf(nfrontp, "%s ", TELOPT(i));
  		    else if (TELCMD_OK(i))
  			sprintf(nfrontp, "%s ", TELCMD(i));
  		    else
  			sprintf(nfrontp, "%d ", i);
  		    nfrontp += strlen(nfrontp);
  		    if (TELOPT_OK(j))
  			sprintf(nfrontp, "%s", TELOPT(j));
  		    else if (TELCMD_OK(j))
  			sprintf(nfrontp, "%s", TELCMD(j));
  		    else
  			sprintf(nfrontp, "%d", j);
  		    nfrontp += strlen(nfrontp);
  		    sprintf(nfrontp, ", not IAC SE!) ");
  		    nfrontp += strlen(nfrontp);
  		}
  	    }
  	    length -= 2;
  	}
  	if (length < 1) {
  	    sprintf(nfrontp, "(Empty suboption??\?)");
  	    nfrontp += strlen(nfrontp);
  	    return;
  	}
  	switch (pointer[0]) {
  	case TELOPT_TTYPE:
  	    sprintf(nfrontp, "TERMINAL-TYPE ");
  	    nfrontp += strlen(nfrontp);
  	    switch (pointer[1]) {
  	    case TELQUAL_IS:
  		sprintf(nfrontp, "IS \"%.*s\"", length-2, (char *)pointer+2);
  		break;
  	    case TELQUAL_SEND:
  		sprintf(nfrontp, "SEND");
  		break;
  	    default:
  		sprintf(nfrontp,
  				"- unknown qualifier %d (0x%x).",
  				pointer[1], pointer[1]);
  	    }
  	    nfrontp += strlen(nfrontp);
  	    break;
  	case TELOPT_TSPEED:
  	    sprintf(nfrontp, "TERMINAL-SPEED");
  	    nfrontp += strlen(nfrontp);
  	    if (length < 2) {
  		sprintf(nfrontp, " (empty suboption??\?)");
  		nfrontp += strlen(nfrontp);
  		break;
  	    }
  	    switch (pointer[1]) {
  	    case TELQUAL_IS:
  		sprintf(nfrontp, " IS %.*s", length-2, (char *)pointer+2);
  		nfrontp += strlen(nfrontp);
  		break;
  	    default:
  		if (pointer[1] == 1)
  		    sprintf(nfrontp, " SEND");
  		else
  		    sprintf(nfrontp, " %d (unknown)", pointer[1]);
  		nfrontp += strlen(nfrontp);
  		for (i = 2; i < length; i++) {
  		    sprintf(nfrontp, " ?%d?", pointer[i]);
  		    nfrontp += strlen(nfrontp);
  		}
  		break;
  	    }
  	    break;
  
  	case TELOPT_LFLOW:
  	    sprintf(nfrontp, "TOGGLE-FLOW-CONTROL");
  	    nfrontp += strlen(nfrontp);
  	    if (length < 2) {
  		sprintf(nfrontp, " (empty suboption??\?)");
  		nfrontp += strlen(nfrontp);
  		break;
  	    }
  	    switch (pointer[1]) {
  	    case LFLOW_OFF:
  		sprintf(nfrontp, " OFF"); break;
  	    case LFLOW_ON:
  		sprintf(nfrontp, " ON"); break;
  	    case LFLOW_RESTART_ANY:
  		sprintf(nfrontp, " RESTART-ANY"); break;
  	    case LFLOW_RESTART_XON:
  		sprintf(nfrontp, " RESTART-XON"); break;
  	    default:
  		sprintf(nfrontp, " %d (unknown)", pointer[1]);
  	    }
  	    nfrontp += strlen(nfrontp);
  	    for (i = 2; i < length; i++) {
  		sprintf(nfrontp, " ?%d?", pointer[i]);
  		nfrontp += strlen(nfrontp);
  	    }
  	    break;
  
  	case TELOPT_NAWS:
  	    sprintf(nfrontp, "NAWS");
  	    nfrontp += strlen(nfrontp);
  	    if (length < 2) {
  		sprintf(nfrontp, " (empty suboption??\?)");
  		nfrontp += strlen(nfrontp);
  		break;
  	    }
  	    if (length == 2) {
  		sprintf(nfrontp, " ?%d?", pointer[1]);
  		nfrontp += strlen(nfrontp);
  		break;
  	    }
  	    sprintf(nfrontp, " %d %d (%d)",
  		pointer[1], pointer[2],
  		(int)((((unsigned int)pointer[1])<<8)|((unsigned int)pointer[2])));
  	    nfrontp += strlen(nfrontp);
  	    if (length == 4) {
  		sprintf(nfrontp, " ?%d?", pointer[3]);
  		nfrontp += strlen(nfrontp);
  		break;
  	    }
  	    sprintf(nfrontp, " %d %d (%d)",
  		pointer[3], pointer[4],
  		(int)((((unsigned int)pointer[3])<<8)|((unsigned int)pointer[4])));
  	    nfrontp += strlen(nfrontp);
  	    for (i = 5; i < length; i++) {
  		sprintf(nfrontp, " ?%d?", pointer[i]);
  		nfrontp += strlen(nfrontp);
  	    }
  	    break;
  
  	case TELOPT_LINEMODE:
  	    sprintf(nfrontp, "LINEMODE ");
  	    nfrontp += strlen(nfrontp);
  	    if (length < 2) {
  		sprintf(nfrontp, " (empty suboption??\?)");
  		nfrontp += strlen(nfrontp);
  		break;
  	    }
  	    switch (pointer[1]) {
  	    case WILL:
  		sprintf(nfrontp, "WILL ");
  		goto common;
  	    case WONT:
  		sprintf(nfrontp, "WONT ");
  		goto common;
  	    case DO:
  		sprintf(nfrontp, "DO ");
  		goto common;
  	    case DONT:
  		sprintf(nfrontp, "DONT ");
  	    common:
  		nfrontp += strlen(nfrontp);
  		if (length < 3) {
  		    sprintf(nfrontp, "(no option??\?)");
  		    nfrontp += strlen(nfrontp);
  		    break;
  		}
  		switch (pointer[2]) {
  		case LM_FORWARDMASK:
  		    sprintf(nfrontp, "Forward Mask");
  		    nfrontp += strlen(nfrontp);
  		    for (i = 3; i < length; i++) {
  			sprintf(nfrontp, " %x", pointer[i]);
  			nfrontp += strlen(nfrontp);
  		    }
  		    break;
  		default:
  		    sprintf(nfrontp, "%d (unknown)", pointer[2]);
  		    nfrontp += strlen(nfrontp);
  		    for (i = 3; i < length; i++) {
  			sprintf(nfrontp, " %d", pointer[i]);
  			nfrontp += strlen(nfrontp);
  		    }
  		    break;
  		}
  		break;
  
  	    case LM_SLC:
  		sprintf(nfrontp, "SLC");
  		nfrontp += strlen(nfrontp);
  		for (i = 2; i < length - 2; i += 3) {
  		    if (SLC_NAME_OK(pointer[i+SLC_FUNC]))
  			sprintf(nfrontp, " %s", SLC_NAME(pointer[i+SLC_FUNC]));
  		    else
  			sprintf(nfrontp, " %d", pointer[i+SLC_FUNC]);
  		    nfrontp += strlen(nfrontp);
  		    switch (pointer[i+SLC_FLAGS]&SLC_LEVELBITS) {
  		    case SLC_NOSUPPORT:
  			sprintf(nfrontp, " NOSUPPORT"); break;
  		    case SLC_CANTCHANGE:
  			sprintf(nfrontp, " CANTCHANGE"); break;
  		    case SLC_VARIABLE:
  			sprintf(nfrontp, " VARIABLE"); break;
  		    case SLC_DEFAULT:
  			sprintf(nfrontp, " DEFAULT"); break;
  		    }
  		    nfrontp += strlen(nfrontp);
  		    sprintf(nfrontp, "%s%s%s",
  			pointer[i+SLC_FLAGS]&SLC_ACK ? "|ACK" : "",
  			pointer[i+SLC_FLAGS]&SLC_FLUSHIN ? "|FLUSHIN" : "",
  			pointer[i+SLC_FLAGS]&SLC_FLUSHOUT ? "|FLUSHOUT" : "");
  		    nfrontp += strlen(nfrontp);
  		    if (pointer[i+SLC_FLAGS]& ~(SLC_ACK|SLC_FLUSHIN|
  						SLC_FLUSHOUT| SLC_LEVELBITS)) {
  			sprintf(nfrontp, "(0x%x)", pointer[i+SLC_FLAGS]);
  			nfrontp += strlen(nfrontp);
  		    }
  		    sprintf(nfrontp, " %d;", pointer[i+SLC_VALUE]);
  		    nfrontp += strlen(nfrontp);
  		    if ((pointer[i+SLC_VALUE] == IAC) &&
  			(pointer[i+SLC_VALUE+1] == IAC))
  				i++;
  		}
  		for (; i < length; i++) {
  		    sprintf(nfrontp, " ?%d?", pointer[i]);
  		    nfrontp += strlen(nfrontp);
  		}
  		break;
  
  	    case LM_MODE:
  		sprintf(nfrontp, "MODE ");
  		nfrontp += strlen(nfrontp);
  		if (length < 3) {
  		    sprintf(nfrontp, "(no mode??\?)");
  		    nfrontp += strlen(nfrontp);
  		    break;
  		}
  		{
  		    char tbuf[32];
  		    sprintf(tbuf, "%s%s%s%s%s",
  			pointer[2]&MODE_EDIT ? "|EDIT" : "",
  			pointer[2]&MODE_TRAPSIG ? "|TRAPSIG" : "",
  			pointer[2]&MODE_SOFT_TAB ? "|SOFT_TAB" : "",
  			pointer[2]&MODE_LIT_ECHO ? "|LIT_ECHO" : "",
  			pointer[2]&MODE_ACK ? "|ACK" : "");
  		    sprintf(nfrontp, "%s", tbuf[1] ? &tbuf[1] : "0");
  		    nfrontp += strlen(nfrontp);
  		}
  		if (pointer[2]&~(MODE_EDIT|MODE_TRAPSIG|MODE_ACK)) {
  		    sprintf(nfrontp, " (0x%x)", pointer[2]);
  		    nfrontp += strlen(nfrontp);
  		}
  		for (i = 3; i < length; i++) {
  		    sprintf(nfrontp, " ?0x%x?", pointer[i]);
  		    nfrontp += strlen(nfrontp);
  		}
  		break;
  	    default:
  		sprintf(nfrontp, "%d (unknown)", pointer[1]);
  		nfrontp += strlen(nfrontp);
  		for (i = 2; i < length; i++) {
  		    sprintf(nfrontp, " %d", pointer[i]);
  		    nfrontp += strlen(nfrontp);
  		}
  	    }
  	    break;
  
  	case TELOPT_STATUS: {
  	    register char *cp;
  	    register int j, k;
  
  	    sprintf(nfrontp, "STATUS");
  	    nfrontp += strlen(nfrontp);
  
  	    switch (pointer[1]) {
  	    default:
  		if (pointer[1] == TELQUAL_SEND)
  		    sprintf(nfrontp, " SEND");
  		else
  		    sprintf(nfrontp, " %d (unknown)", pointer[1]);
  		nfrontp += strlen(nfrontp);
  		for (i = 2; i < length; i++) {
  		    sprintf(nfrontp, " ?%d?", pointer[i]);
  		    nfrontp += strlen(nfrontp);
  		}
  		break;
  	    case TELQUAL_IS:
  		sprintf(nfrontp, " IS\r\n");
  		nfrontp += strlen(nfrontp);
  
  		for (i = 2; i < length; i++) {
  		    switch(pointer[i]) {
  		    case DO:	cp = "DO"; goto common2;
  		    case DONT:	cp = "DONT"; goto common2;
  		    case WILL:	cp = "WILL"; goto common2;
  		    case WONT:	cp = "WONT"; goto common2;
  		    common2:
  			i++;
  			if (TELOPT_OK(pointer[i]))
  			    sprintf(nfrontp, " %s %s", cp, TELOPT(pointer[i]));
  			else
  			    sprintf(nfrontp, " %s %d", cp, pointer[i]);
  			nfrontp += strlen(nfrontp);
  
  			sprintf(nfrontp, "\r\n");
  			nfrontp += strlen(nfrontp);
  			break;
  
  		    case SB:
  			sprintf(nfrontp, " SB ");
  			nfrontp += strlen(nfrontp);
  			i++;
  			j = k = i;
  			while (j < length) {
  			    if (pointer[j] == SE) {
  				if (j+1 == length)
  				    break;
  				if (pointer[j+1] == SE)
  				    j++;
  				else
  				    break;
  			    }
  			    pointer[k++] = pointer[j++];
  			}
  			printsub(0, &pointer[i], k - i);
  			if (i < length) {
  			    sprintf(nfrontp, " SE");
  			    nfrontp += strlen(nfrontp);
  			    i = j;
  			} else
  			    i = j - 1;
  
  			sprintf(nfrontp, "\r\n");
  			nfrontp += strlen(nfrontp);
  
  			break;
  
  		    default:
  			sprintf(nfrontp, " %d", pointer[i]);
  			nfrontp += strlen(nfrontp);
  			break;
  		    }
  		}
  		break;
  	    }
  	    break;
  	  }
  
  	case TELOPT_XDISPLOC:
  	    sprintf(nfrontp, "X-DISPLAY-LOCATION ");
  	    nfrontp += strlen(nfrontp);
  	    switch (pointer[1]) {
  	    case TELQUAL_IS:
  		sprintf(nfrontp, "IS \"%.*s\"", length-2, (char *)pointer+2);
  		break;
  	    case TELQUAL_SEND:
  		sprintf(nfrontp, "SEND");
  		break;
  	    default:
  		sprintf(nfrontp, "- unknown qualifier %d (0x%x).",
  				pointer[1], pointer[1]);
  	    }
  	    nfrontp += strlen(nfrontp);
  	    break;
  
  	case TELOPT_NEW_ENVIRON:
  	    sprintf(nfrontp, "NEW-ENVIRON ");
  	    goto env_common1;
  	case TELOPT_OLD_ENVIRON:
  	    sprintf(nfrontp, "OLD-ENVIRON");
  	env_common1:
  	    nfrontp += strlen(nfrontp);
  	    switch (pointer[1]) {
  	    case TELQUAL_IS:
  		sprintf(nfrontp, "IS ");
  		goto env_common;
  	    case TELQUAL_SEND:
  		sprintf(nfrontp, "SEND ");
  		goto env_common;
  	    case TELQUAL_INFO:
  		sprintf(nfrontp, "INFO ");
  	    env_common:
  		nfrontp += strlen(nfrontp);
  		{
  		    register int noquote = 2;
  		    for (i = 2; i < length; i++ ) {
  			switch (pointer[i]) {
  			case NEW_ENV_VAR:
  			    sprintf(nfrontp, "\" VAR " + noquote);
  			    nfrontp += strlen(nfrontp);
  			    noquote = 2;
  			    break;
  
  			case NEW_ENV_VALUE:
  			    sprintf(nfrontp, "\" VALUE " + noquote);
  			    nfrontp += strlen(nfrontp);
  			    noquote = 2;
  			    break;
  
  			case ENV_ESC:
  			    sprintf(nfrontp, "\" ESC " + noquote);
  			    nfrontp += strlen(nfrontp);
  			    noquote = 2;
  			    break;
  
  			case ENV_USERVAR:
  			    sprintf(nfrontp, "\" USERVAR " + noquote);
  			    nfrontp += strlen(nfrontp);
  			    noquote = 2;
  			    break;
  
  			default:
  			    if (isprint(pointer[i]) && pointer[i] != '"') {
  				if (noquote) {
  				    *nfrontp++ = '"';
  				    noquote = 0;
  				}
  				*nfrontp++ = pointer[i];
  			    } else {
  				sprintf(nfrontp, "\" %03o " + noquote,
  							pointer[i]);
  				nfrontp += strlen(nfrontp);
  				noquote = 2;
  			    }
  			    break;
  			}
  		    }
  		    if (!noquote)
  			*nfrontp++ = '"';
  		    break;
  		}
  	    }
  	    break;
  
  #if	defined(AUTHENTICATION)
  	case TELOPT_AUTHENTICATION:
  	    sprintf(nfrontp, "AUTHENTICATION");
  	    nfrontp += strlen(nfrontp);
  
  	    if (length < 2) {
  		sprintf(nfrontp, " (empty suboption??\?)");
  		nfrontp += strlen(nfrontp);
  		break;
  	    }
  	    switch (pointer[1]) {
  	    case TELQUAL_REPLY:
  	    case TELQUAL_IS:
  		sprintf(nfrontp, " %s ", (pointer[1] == TELQUAL_IS) ?
  							"IS" : "REPLY");
  		nfrontp += strlen(nfrontp);
  		if (AUTHTYPE_NAME_OK(pointer[2]))
  		    sprintf(nfrontp, "%s ", AUTHTYPE_NAME(pointer[2]));
  		else
  		    sprintf(nfrontp, "%d ", pointer[2]);
  		nfrontp += strlen(nfrontp);
  		if (length < 3) {
  		    sprintf(nfrontp, "(partial suboption??\?)");
  		    nfrontp += strlen(nfrontp);
  		    break;
  		}
  		sprintf(nfrontp, "%s|%s",
  			((pointer[3] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
  			"CLIENT" : "SERVER",
  			((pointer[3] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
  			"MUTUAL" : "ONE-WAY");
  		nfrontp += strlen(nfrontp);
  
      		{
  		    char buf[512];
  		    auth_printsub(&pointer[1], length - 1, buf, sizeof(buf));
  		    sprintf(nfrontp, "%s", buf);
  		}
  		nfrontp += strlen(nfrontp);
  		break;
  
  	    case TELQUAL_SEND:
  		i = 2;
  		sprintf(nfrontp, " SEND ");
  		nfrontp += strlen(nfrontp);
  		while (i < length) {
  		    if (AUTHTYPE_NAME_OK(pointer[i]))
  			sprintf(nfrontp, "%s ", AUTHTYPE_NAME(pointer[i]));
  		    else
  			sprintf(nfrontp, "%d ", pointer[i]);
  		    nfrontp += strlen(nfrontp);
  		    if (++i >= length) {
  			sprintf(nfrontp, "(partial suboption??\?)");
  			nfrontp += strlen(nfrontp);
  			break;
  		    }
  		    sprintf(nfrontp, "%s|%s ",
  			((pointer[i] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
  							"CLIENT" : "SERVER",
  			((pointer[i] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
  							"MUTUAL" : "ONE-WAY");
  		    nfrontp += strlen(nfrontp);
  		    ++i;
  		}
  		break;
  
  	    case TELQUAL_NAME:
  		i = 2;
  		sprintf(nfrontp, " NAME \"");
  		nfrontp += strlen(nfrontp);
  		while (i < length)
  		    *nfrontp += pointer[i++];
  		*nfrontp += '"';
  		break;
  
  	    default:
  		    for (i = 2; i < length; i++) {
  			sprintf(nfrontp, " ?%d?", pointer[i]);
  			nfrontp += strlen(nfrontp);
  		    }
  		    break;
  	    }
  	    break;
  #endif
  
  
  	default:
  	    if (TELOPT_OK(pointer[0]))
  	        sprintf(nfrontp, "%s (unknown)", TELOPT(pointer[0]));
  	    else
  	        sprintf(nfrontp, "%d (unknown)", pointer[i]);
  	    nfrontp += strlen(nfrontp);
  	    for (i = 1; i < length; i++) {
  		sprintf(nfrontp, " %d", pointer[i]);
  		nfrontp += strlen(nfrontp);
  	    }
  	    break;
  	}
  	sprintf(nfrontp, "\r\n");
  	nfrontp += strlen(nfrontp);
  }
  
  /*
   * Dump a data buffer in hex and ascii to the output data stream.
   */
  	void
  printdata(tag, ptr, cnt)
  	register char *tag;
  	register char *ptr;
  	register int cnt;
  {
  	register int i;
  	char xbuf[30];
  
  	while (cnt) {
  		/* flush net output buffer if no room for new data) */
  		if ((&netobuf[BUFSIZ] - nfrontp) < 80) {
  			netflush();
  		}
  
  		/* add a line of output */
  		sprintf(nfrontp, "%s: ", tag);
  		nfrontp += strlen(nfrontp);
  		for (i = 0; i < 20 && cnt; i++) {
  			sprintf(nfrontp, "%02x", *ptr);
  			nfrontp += strlen(nfrontp);
  			if (isprint(*ptr)) {
  				xbuf[i] = *ptr;
  			} else {
  				xbuf[i] = '.';
  			}
  			if (i % 2) {
  				*nfrontp = ' ';
  				nfrontp++;
  			}
  			cnt--;
  			ptr++;
  		}
  		xbuf[i] = '\0';
  		sprintf(nfrontp, " %s\r\n", xbuf );
  		nfrontp += strlen(nfrontp);
  	}
  }
  #endif /* DIAGNOSTICS */
  