xref: /netbsd/libexec/telnetd/utility.c (revision bf9ec67e)
1 /*	$NetBSD: utility.c,v 1.18 2001/07/19 04:57:50 itojun Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)utility.c	8.4 (Berkeley) 5/30/95";
40 #else
41 __RCSID("$NetBSD: utility.c,v 1.18 2001/07/19 04:57:50 itojun Exp $");
42 #endif
43 #endif /* not lint */
44 
45 #include <sys/utsname.h>
46 #define PRINTOPTIONS
47 #include "telnetd.h"
48 
49 char *nextitem __P((char *));
50 void putstr __P((char *));
51 
52 extern int not42;
53 
54 /*
55  * utility functions performing io related tasks
56  */
57 
58 /*
59  * ttloop
60  *
61  *	A small subroutine to flush the network output buffer, get some data
62  * from the network, and pass it through the telnet state machine.  We
63  * also flush the pty input buffer (by dropping its data) if it becomes
64  * too full.
65  */
66 
67     void
68 ttloop()
69 {
70 
71     DIAG(TD_REPORT, {output_data("td: ttloop\r\n");});
72     if (nfrontp - nbackp) {
73 	netflush();
74     }
75     ncc = read(net, netibuf, sizeof netibuf);
76     if (ncc < 0) {
77 	syslog(LOG_ERR, "ttloop:  read: %m");
78 	exit(1);
79     } else if (ncc == 0) {
80 	syslog(LOG_ERR, "ttloop:  peer died: %m");
81 	exit(1);
82     }
83     DIAG(TD_REPORT, {output_data("td: ttloop read %d chars\r\n", ncc);});
84     netip = netibuf;
85     telrcv();			/* state machine */
86     if (ncc > 0) {
87 	pfrontp = pbackp = ptyobuf;
88 	telrcv();
89     }
90 }  /* end of ttloop */
91 
92 /*
93  * Check a descriptor to see if out of band data exists on it.
94  */
95     int
96 stilloob(s)
97     int	s;		/* socket number */
98 {
99     static struct timeval timeout = { 0 };
100     fd_set	excepts;
101     int value;
102 
103     if (s >= FD_SETSIZE)
104 	fatal(pty, "fd too large");
105 
106     do {
107 	FD_ZERO(&excepts);
108 	FD_SET(s, &excepts);
109 	value = select(s+1, (fd_set *)0, (fd_set *)0, &excepts, &timeout);
110     } while ((value == -1) && (errno == EINTR));
111 
112     if (value < 0) {
113 	fatalperror(pty, "select");
114     }
115     if (FD_ISSET(s, &excepts)) {
116 	return 1;
117     } else {
118 	return 0;
119     }
120 }
121 
122 	void
123 ptyflush()
124 {
125 	int n;
126 
127 	if ((n = pfrontp - pbackp) > 0) {
128 		DIAG((TD_REPORT | TD_PTYDATA),
129 			{ output_data("td: ptyflush %d chars\r\n", n); });
130 		DIAG(TD_PTYDATA, printdata("pd", pbackp, n));
131 		n = write(pty, pbackp, n);
132 	}
133 	if (n < 0) {
134 		if (errno == EWOULDBLOCK || errno == EINTR)
135 			return;
136 		cleanup(0);
137 	}
138 	pbackp += n;
139 	if (pbackp == pfrontp)
140 		pbackp = pfrontp = ptyobuf;
141 }
142 
143 /*
144  * nextitem()
145  *
146  *	Return the address of the next "item" in the TELNET data
147  * stream.  This will be the address of the next character if
148  * the current address is a user data character, or it will
149  * be the address of the character following the TELNET command
150  * if the current address is a TELNET IAC ("I Am a Command")
151  * character.
152  */
153     char *
154 nextitem(current)
155     char	*current;
156 {
157     if ((*current&0xff) != IAC) {
158 	return current+1;
159     }
160     switch (*(current+1)&0xff) {
161     case DO:
162     case DONT:
163     case WILL:
164     case WONT:
165 	return current+3;
166     case SB:		/* loop forever looking for the SE */
167 	{
168 	    register char *look = current+2;
169 
170 	    for (;;) {
171 		if ((*look++&0xff) == IAC) {
172 		    if ((*look++&0xff) == SE) {
173 			return look;
174 		    }
175 		}
176 	    }
177 	}
178     default:
179 	return current+2;
180     }
181 }  /* end of nextitem */
182 
183 
184 /*
185  * netclear()
186  *
187  *	We are about to do a TELNET SYNCH operation.  Clear
188  * the path to the network.
189  *
190  *	Things are a bit tricky since we may have sent the first
191  * byte or so of a previous TELNET command into the network.
192  * So, we have to scan the network buffer from the beginning
193  * until we are up to where we want to be.
194  *
195  *	A side effect of what we do, just to keep things
196  * simple, is to clear the urgent data pointer.  The principal
197  * caller should be setting the urgent data pointer AFTER calling
198  * us in any case.
199  */
200     void
201 netclear()
202 {
203     register char *thisitem, *next;
204     char *good;
205 #define	wewant(p)	((nfrontp > p) && ((*p&0xff) == IAC) && \
206 				((*(p+1)&0xff) != EC) && ((*(p+1)&0xff) != EL))
207 
208 #ifdef	ENCRYPTION
209     thisitem = nclearto > netobuf ? nclearto : netobuf;
210 #else /* ENCRYPTION */
211     thisitem = netobuf;
212 #endif	/* ENCRYPTION */
213 
214     while ((next = nextitem(thisitem)) <= nbackp) {
215 	thisitem = next;
216     }
217 
218     /* Now, thisitem is first before/at boundary. */
219 
220 #ifdef	ENCRYPTION
221     good = nclearto > netobuf ? nclearto : netobuf;
222 #else /* ENCRYPTION */
223     good = netobuf;	/* where the good bytes go */
224 #endif	/* ENCRYPTION */
225 
226     while (nfrontp > thisitem) {
227 	if (wewant(thisitem)) {
228 	    int length;
229 
230 	    next = thisitem;
231 	    do {
232 		next = nextitem(next);
233 	    } while (wewant(next) && (nfrontp > next));
234 	    length = next-thisitem;
235 	    memmove(good, thisitem, length);
236 	    good += length;
237 	    thisitem = next;
238 	} else {
239 	    thisitem = nextitem(thisitem);
240 	}
241     }
242 
243     nbackp = netobuf;
244     nfrontp = good;		/* next byte to be sent */
245     neturg = 0;
246 }  /* end of netclear */
247 
248 /*
249  *  netflush
250  *		Send as much data as possible to the network,
251  *	handling requests for urgent data.
252  */
253     void
254 netflush()
255 {
256     int n;
257 
258     if ((n = nfrontp - nbackp) > 0) {
259 	DIAG(TD_REPORT,
260 	    { output_data("td: netflush %d chars\r\n", n);
261 	      n = nfrontp - nbackp;	/* re-compute count */
262 	    });
263 #ifdef	ENCRYPTION
264 	if (encrypt_output) {
265 		char *s = nclearto ? nclearto : nbackp;
266 		if (nfrontp - s > 0) {
267 			(*encrypt_output)((unsigned char *)s, nfrontp - s);
268 			nclearto = nfrontp;
269 		}
270 	}
271 #endif	/* ENCRYPTION */
272 	/*
273 	 * if no urgent data, or if the other side appears to be an
274 	 * old 4.2 client (and thus unable to survive TCP urgent data),
275 	 * write the entire buffer in non-OOB mode.
276 	 */
277 	if ((neturg == 0) || (not42 == 0)) {
278 	    n = write(net, nbackp, n);	/* normal write */
279 	} else {
280 	    n = neturg - nbackp;
281 	    /*
282 	     * In 4.2 (and 4.3) systems, there is some question about
283 	     * what byte in a sendOOB operation is the "OOB" data.
284 	     * To make ourselves compatible, we only send ONE byte
285 	     * out of band, the one WE THINK should be OOB (though
286 	     * we really have more the TCP philosophy of urgent data
287 	     * rather than the Unix philosophy of OOB data).
288 	     */
289 	    if (n > 1) {
290 		n = send(net, nbackp, n-1, 0);	/* send URGENT all by itself */
291 	    } else {
292 		n = send(net, nbackp, n, MSG_OOB);	/* URGENT data */
293 	    }
294 	}
295     }
296     if (n < 0) {
297 	if (errno == EWOULDBLOCK || errno == EINTR)
298 		return;
299 	cleanup(0);
300     }
301     nbackp += n;
302 #ifdef	ENCRYPTION
303     if (nbackp > nclearto)
304 	nclearto = 0;
305 #endif	/* ENCRYPTION */
306     if (nbackp >= neturg) {
307 	neturg = 0;
308     }
309     if (nbackp == nfrontp) {
310 	nbackp = nfrontp = netobuf;
311 #ifdef	ENCRYPTION
312 	nclearto = 0;
313 #endif	/* ENCRYPTION */
314     }
315     return;
316 }  /* end of netflush */
317 
318 
319 /*
320  * writenet
321  *
322  * Just a handy little function to write a bit of raw data to the net.
323  * It will force a transmit of the buffer if necessary
324  *
325  * arguments
326  *    ptr - A pointer to a character string to write
327  *    len - How many bytes to write
328  */
329 	void
330 writenet(ptr, len)
331 	register unsigned char *ptr;
332 	register int len;
333 {
334 	/* flush buffer if no room for new data) */
335 	if ((&netobuf[BUFSIZ] - nfrontp) < len) {
336 		/* if this fails, don't worry, buffer is a little big */
337 		netflush();
338 	}
339 
340 	memmove(nfrontp, ptr, len);
341 	nfrontp += len;
342 
343 }  /* end of writenet */
344 
345 
346 /*
347  * miscellaneous functions doing a variety of little jobs follow ...
348  */
349 
350 
351 	void
352 fatal(f, msg)
353 	int f;
354 	const char *msg;
355 {
356 	char buf[BUFSIZ];
357 
358 	(void)snprintf(buf, sizeof buf, "telnetd: %s.\r\n", msg);
359 #ifdef	ENCRYPTION
360 	if (encrypt_output) {
361 		/*
362 		 * Better turn off encryption first....
363 		 * Hope it flushes...
364 		 */
365 		encrypt_send_end();
366 		netflush();
367 	}
368 #endif	/* ENCRYPTION */
369 	(void)write(f, buf, (int)strlen(buf));
370 	sleep(1);	/*XXX*/
371 	exit(1);
372 }
373 
374 	void
375 fatalperror(f, msg)
376 	int f;
377 	const char *msg;
378 {
379 	char buf[BUFSIZ];
380 
381 	(void)snprintf(buf, sizeof buf, "%s: %s", msg, strerror(errno));
382 	fatal(f, buf);
383 }
384 
385 char editedhost[MAXHOSTNAMELEN];
386 
387 	void
388 edithost(pat, host)
389 	register char *pat;
390 	register char *host;
391 {
392 	register char *res = editedhost;
393 
394 	if (!pat)
395 		pat = "";
396 	while (*pat) {
397 		switch (*pat) {
398 
399 		case '#':
400 			if (*host)
401 				host++;
402 			break;
403 
404 		case '@':
405 			if (*host)
406 				*res++ = *host++;
407 			break;
408 
409 		default:
410 			*res++ = *pat;
411 			break;
412 		}
413 		if (res == &editedhost[sizeof editedhost - 1]) {
414 			*res = '\0';
415 			return;
416 		}
417 		pat++;
418 	}
419 	if (*host)
420 		(void) strncpy(res, host,
421 		    sizeof editedhost - (res - editedhost) -1);
422 	else
423 		*res = '\0';
424 	editedhost[sizeof editedhost - 1] = '\0';
425 }
426 
427 static char *putlocation;
428 
429 	void
430 putstr(s)
431 	register char *s;
432 {
433 
434 	while (*s)
435 		putchr(*s++);
436 }
437 
438 	void
439 putchr(cc)
440 	int cc;
441 {
442 	*putlocation++ = cc;
443 }
444 
445 /*
446  * This is split on two lines so that SCCS will not see the M
447  * between two % signs and expand it...
448  */
449 static char fmtstr[] = { "%l:%M\
450 %p on %A, %d %B %Y" };
451 
452 	char *
453 putf(cp, where)
454 	register char *cp;
455 	char *where;
456 {
457 	char *slash;
458 	time_t t;
459 	char db[100];
460 	struct utsname utsinfo;
461 
462 	uname(&utsinfo);
463 
464 	putlocation = where;
465 
466 	while (*cp) {
467 		if (*cp != '%') {
468 			putchr(*cp++);
469 			continue;
470 		}
471 		switch (*++cp) {
472 
473 		case 't':
474 #ifdef	STREAMSPTY
475 			/* names are like /dev/pts/2 -- we want pts/2 */
476 			slash = strchr(line+1, '/');
477 #else
478 			slash = strrchr(line, '/');
479 #endif
480 			if (slash == (char *) 0)
481 				putstr(line);
482 			else
483 				putstr(&slash[1]);
484 			break;
485 
486 		case 'h':
487 			putstr(editedhost);
488 			break;
489 
490 		case 'd':
491 			(void)time(&t);
492 			(void)strftime(db, sizeof(db), fmtstr, localtime(&t));
493 			putstr(db);
494 			break;
495 
496 		case '%':
497 			putchr('%');
498 			break;
499 
500 		case 's':
501 			putstr(utsinfo.sysname);
502 			break;
503 
504 		case 'm':
505 			putstr(utsinfo.machine);
506 			break;
507 
508 		case 'r':
509 			putstr(utsinfo.release);
510 			break;
511 
512 		case 'v':
513 			puts(utsinfo.version);
514                         break;
515 		}
516 		cp++;
517 	}
518 
519 	return (putlocation);
520 }
521 
522 #ifdef DIAGNOSTICS
523 /*
524  * Print telnet options and commands in plain text, if possible.
525  */
526 	void
527 printoption(fmt, option)
528 	register const char *fmt;
529 	register int option;
530 {
531 	if (TELOPT_OK(option))
532 		output_data("%s %s\r\n", fmt, TELOPT(option));
533 	else if (TELCMD_OK(option))
534 		output_data("%s %s\r\n", fmt, TELCMD(option));
535 	else
536 		output_data("%s %d\r\n", fmt, option);
537 	return;
538 }
539 
540     void
541 printsub(direction, pointer, length)
542     char		direction;	/* '<' or '>' */
543     unsigned char	*pointer;	/* where suboption data sits */
544     int			length;		/* length of suboption data */
545 {
546     register int i = 0;		/* XXX gcc */
547 #if	defined(AUTHENTICATION) || defined(ENCRYPTION)
548     char buf[512];
549 #endif
550 
551 	if (!(diagnostic & TD_OPTIONS))
552 		return;
553 
554 	if (direction) {
555 	    output_data("td: %s suboption ",
556 	        direction == '<' ? "recv" : "send");
557 	    if (length >= 3) {
558 		register int j;
559 
560 		i = pointer[length - 2];
561 		j = pointer[length - 1];
562 
563 		if (i != IAC || j != SE) {
564 		    output_data("(terminated by ");
565 		    if (TELOPT_OK(i))
566 			output_data("%s ", TELOPT(i));
567 		    else if (TELCMD_OK(i))
568 			output_data("%s ", TELCMD(i));
569 		    else
570 			output_data("%d ", i);
571 		    if (TELOPT_OK(j))
572 			output_data("%s", TELOPT(j));
573 		    else if (TELCMD_OK(j))
574 			output_data("%s", TELCMD(j));
575 		    else
576 			output_data("%d", j);
577 		    output_data(", not IAC SE!) ");
578 		}
579 	    }
580 	    length -= 2;
581 	}
582 	if (length < 1) {
583 	    output_data("(Empty suboption??\?)");
584 	    return;
585 	}
586 	switch (pointer[0]) {
587 	case TELOPT_TTYPE:
588 	    output_data("TERMINAL-TYPE ");
589 	    switch (pointer[1]) {
590 	    case TELQUAL_IS:
591 		output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
592 		break;
593 	    case TELQUAL_SEND:
594 		output_data("SEND");
595 		break;
596 	    default:
597 		output_data("- unknown qualifier %d (0x%x).",
598 		    pointer[1], pointer[1]);
599 	    }
600 	    break;
601 	case TELOPT_TSPEED:
602 	    output_data("TERMINAL-SPEED");
603 	    if (length < 2) {
604 		output_data(" (empty suboption??\?)");
605 		break;
606 	    }
607 	    switch (pointer[1]) {
608 	    case TELQUAL_IS:
609 		output_data(" IS %.*s", length-2, (char *)pointer+2);
610 		break;
611 	    default:
612 		if (pointer[1] == 1)
613 		    output_data(" SEND");
614 		else
615 		    output_data(" %d (unknown)", pointer[1]);
616 		for (i = 2; i < length; i++) {
617 		    output_data(" ?%d?", pointer[i]);
618 		}
619 		break;
620 	    }
621 	    break;
622 
623 	case TELOPT_LFLOW:
624 	    output_data("TOGGLE-FLOW-CONTROL");
625 	    if (length < 2) {
626 		output_data(" (empty suboption??\?)");
627 		break;
628 	    }
629 	    switch (pointer[1]) {
630 	    case LFLOW_OFF:
631 		output_data(" OFF"); break;
632 	    case LFLOW_ON:
633 		output_data(" ON"); break;
634 	    case LFLOW_RESTART_ANY:
635 		output_data(" RESTART-ANY"); break;
636 	    case LFLOW_RESTART_XON:
637 		output_data(" RESTART-XON"); break;
638 	    default:
639 		output_data(" %d (unknown)", pointer[1]);
640 	    }
641 	    for (i = 2; i < length; i++)
642 		output_data(" ?%d?", pointer[i]);
643 	    break;
644 
645 	case TELOPT_NAWS:
646 	    output_data("NAWS");
647 	    if (length < 2) {
648 		output_data(" (empty suboption??\?)");
649 		break;
650 	    }
651 	    if (length == 2) {
652 		output_data(" ?%d?", pointer[1]);
653 		break;
654 	    }
655 	    output_data(" %d %d (%d)",
656 		pointer[1], pointer[2],
657 		(int)((((unsigned int)pointer[1])<<8)|((unsigned int)pointer[2])));
658 	    if (length == 4) {
659 		output_data(" ?%d?", pointer[3]);
660 		break;
661 	    }
662 	    output_data(" %d %d (%d)", pointer[3], pointer[4],
663 		(int)((((unsigned int)pointer[3])<<8)|((unsigned int)pointer[4])));
664 	    for (i = 5; i < length; i++) {
665 		output_data(" ?%d?", pointer[i]);
666 	    }
667 	    break;
668 
669 	case TELOPT_LINEMODE:
670 	    output_data("LINEMODE ");
671 	    if (length < 2) {
672 		output_data(" (empty suboption??\?)");
673 		break;
674 	    }
675 	    switch (pointer[1]) {
676 	    case WILL:
677 		output_data("WILL ");
678 		goto common;
679 	    case WONT:
680 		output_data("WONT ");
681 		goto common;
682 	    case DO:
683 		output_data("DO ");
684 		goto common;
685 	    case DONT:
686 		output_data("DONT ");
687 	    common:
688 		if (length < 3) {
689 		    output_data("(no option??\?)");
690 		    break;
691 		}
692 		switch (pointer[2]) {
693 		case LM_FORWARDMASK:
694 		    output_data("Forward Mask");
695 		    for (i = 3; i < length; i++)
696 			output_data(" %x", pointer[i]);
697 		    break;
698 		default:
699 		    output_data("%d (unknown)", pointer[2]);
700 		    for (i = 3; i < length; i++)
701 			output_data(" %d", pointer[i]);
702 		    break;
703 		}
704 		break;
705 
706 	    case LM_SLC:
707 		output_data("SLC");
708 		for (i = 2; i < length - 2; i += 3) {
709 		    if (SLC_NAME_OK(pointer[i+SLC_FUNC]))
710 			output_data(" %s", SLC_NAME(pointer[i+SLC_FUNC]));
711 		    else
712 			output_data(" %d", pointer[i+SLC_FUNC]);
713 		    switch (pointer[i+SLC_FLAGS]&SLC_LEVELBITS) {
714 		    case SLC_NOSUPPORT:
715 			output_data(" NOSUPPORT"); break;
716 		    case SLC_CANTCHANGE:
717 			output_data(" CANTCHANGE"); break;
718 		    case SLC_VARIABLE:
719 			output_data(" VARIABLE"); break;
720 		    case SLC_DEFAULT:
721 			output_data(" DEFAULT"); break;
722 		    }
723 		    output_data("%s%s%s",
724 			pointer[i+SLC_FLAGS]&SLC_ACK ? "|ACK" : "",
725 			pointer[i+SLC_FLAGS]&SLC_FLUSHIN ? "|FLUSHIN" : "",
726 			pointer[i+SLC_FLAGS]&SLC_FLUSHOUT ? "|FLUSHOUT" : "");
727 		    if (pointer[i+SLC_FLAGS]& ~(SLC_ACK|SLC_FLUSHIN|
728 						SLC_FLUSHOUT| SLC_LEVELBITS)) {
729 			output_data("(0x%x)", pointer[i+SLC_FLAGS]);
730 		    }
731 		    output_data(" %d;", pointer[i+SLC_VALUE]);
732 		    if ((pointer[i+SLC_VALUE] == IAC) &&
733 			(pointer[i+SLC_VALUE+1] == IAC))
734 				i++;
735 		}
736 		for (; i < length; i++)
737 		    output_data(" ?%d?", pointer[i]);
738 		break;
739 
740 	    case LM_MODE:
741 		output_data("MODE ");
742 		if (length < 3) {
743 		    output_data("(no mode??\?)");
744 		    break;
745 		}
746 		{
747 		    char tbuf[32];
748 
749 		    (void)snprintf(tbuf, sizeof tbuf, "%s%s%s%s%s",
750 			pointer[2]&MODE_EDIT ? "|EDIT" : "",
751 			pointer[2]&MODE_TRAPSIG ? "|TRAPSIG" : "",
752 			pointer[2]&MODE_SOFT_TAB ? "|SOFT_TAB" : "",
753 			pointer[2]&MODE_LIT_ECHO ? "|LIT_ECHO" : "",
754 			pointer[2]&MODE_ACK ? "|ACK" : "");
755 		    output_data("%s", tbuf[1] ? &tbuf[1] : "0");
756 		}
757 		if (pointer[2]&~(MODE_EDIT|MODE_TRAPSIG|MODE_ACK))
758 		    output_data(" (0x%x)", pointer[2]);
759 		for (i = 3; i < length; i++)
760 		    output_data(" ?0x%x?", pointer[i]);
761 		break;
762 	    default:
763 		output_data("%d (unknown)", pointer[1]);
764 		for (i = 2; i < length; i++)
765 		    output_data(" %d", pointer[i]);
766 	    }
767 	    break;
768 
769 	case TELOPT_STATUS: {
770 	    register char *cp;
771 	    register int j, k;
772 
773 	    output_data("STATUS");
774 
775 	    switch (pointer[1]) {
776 	    default:
777 		if (pointer[1] == TELQUAL_SEND)
778 		    output_data(" SEND");
779 		else
780 		    output_data(" %d (unknown)", pointer[1]);
781 		for (i = 2; i < length; i++)
782 		    output_data(" ?%d?", pointer[i]);
783 		break;
784 	    case TELQUAL_IS:
785 		output_data(" IS\r\n");
786 
787 		for (i = 2; i < length; i++) {
788 		    switch(pointer[i]) {
789 		    case DO:	cp = "DO"; goto common2;
790 		    case DONT:	cp = "DONT"; goto common2;
791 		    case WILL:	cp = "WILL"; goto common2;
792 		    case WONT:	cp = "WONT"; goto common2;
793 		    common2:
794 			i++;
795 			if (TELOPT_OK(pointer[i]))
796 			    output_data(" %s %s", cp, TELOPT(pointer[i]));
797 			else
798 			    output_data(" %s %d", cp, pointer[i]);
799 
800 			output_data("\r\n");
801 			break;
802 
803 		    case SB:
804 			output_data(" SB ");
805 			i++;
806 			j = k = i;
807 			while (j < length) {
808 			    if (pointer[j] == SE) {
809 				if (j+1 == length)
810 				    break;
811 				if (pointer[j+1] == SE)
812 				    j++;
813 				else
814 				    break;
815 			    }
816 			    pointer[k++] = pointer[j++];
817 			}
818 			printsub(0, &pointer[i], k - i);
819 			if (i < length) {
820 			    output_data(" SE");
821 			    i = j;
822 			} else
823 			    i = j - 1;
824 
825 			output_data("\r\n");
826 
827 			break;
828 
829 		    default:
830 			output_data(" %d", pointer[i]);
831 			break;
832 		    }
833 		}
834 		break;
835 	    }
836 	    break;
837 	  }
838 
839 	case TELOPT_XDISPLOC:
840 	    output_data("X-DISPLAY-LOCATION ");
841 	    switch (pointer[1]) {
842 	    case TELQUAL_IS:
843 		output_data("IS \"%.*s\"", length - 2, (char *)pointer + 2);
844 		break;
845 	    case TELQUAL_SEND:
846 		output_data("SEND");
847 		break;
848 	    default:
849 		output_data("- unknown qualifier %d (0x%x).",
850 		    pointer[1], pointer[1]);
851 	    }
852 	    break;
853 
854 	case TELOPT_NEW_ENVIRON:
855 	    output_data("NEW-ENVIRON ");
856 	    goto env_common1;
857 	case TELOPT_OLD_ENVIRON:
858 	    output_data("OLD-ENVIRON");
859 	env_common1:
860 	    switch (pointer[1]) {
861 	    case TELQUAL_IS:
862 		output_data("IS ");
863 		goto env_common;
864 	    case TELQUAL_SEND:
865 		output_data("SEND ");
866 		goto env_common;
867 	    case TELQUAL_INFO:
868 		output_data("INFO ");
869 	    env_common:
870 		{
871 		    register int noquote = 2;
872 		    for (i = 2; i < length; i++ ) {
873 			switch (pointer[i]) {
874 			case NEW_ENV_VAR:
875 			    output_data("%s", "\" VAR " + noquote);
876 			    noquote = 2;
877 			    break;
878 
879 			case NEW_ENV_VALUE:
880 			    output_data("%s", "\" VALUE " + noquote);
881 			    noquote = 2;
882 			    break;
883 
884 			case ENV_ESC:
885 			    output_data("%s", "\" ESC " + noquote);
886 			    noquote = 2;
887 			    break;
888 
889 			case ENV_USERVAR:
890 			    output_data("%s", "\" USERVAR " + noquote);
891 			    noquote = 2;
892 			    break;
893 
894 			default:
895 			    if (isprint(pointer[i]) && pointer[i] != '"') {
896 				if (noquote) {
897 				    output_data("\"");
898 				    noquote = 0;
899 				}
900 				output_data("%c", pointer[i]);
901 			    } else {
902 				output_data("\" %03o " + noquote, pointer[i]);
903 				noquote = 2;
904 			    }
905 			    break;
906 			}
907 		    }
908 		    if (!noquote)
909 			output_data("\"");
910 		    break;
911 		}
912 	    }
913 	    break;
914 
915 #if	defined(AUTHENTICATION)
916 	case TELOPT_AUTHENTICATION:
917 	    output_data("AUTHENTICATION");
918 
919 	    if (length < 2) {
920 		output_data(" (empty suboption??\?)");
921 		break;
922 	    }
923 	    switch (pointer[1]) {
924 	    case TELQUAL_REPLY:
925 	    case TELQUAL_IS:
926 		output_data(" %s ", (pointer[1] == TELQUAL_IS) ?
927 		    "IS" : "REPLY");
928 		if (AUTHTYPE_NAME_OK(pointer[2]))
929 		    output_data("%s ", AUTHTYPE_NAME(pointer[2]));
930 		else
931 		    output_data("%d ", pointer[2]);
932 		if (length < 3) {
933 		    output_data("(partial suboption??\?)");
934 		    break;
935 		}
936 		output_data("%s|%s",
937 			((pointer[3] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
938 			"CLIENT" : "SERVER",
939 			((pointer[3] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
940 			"MUTUAL" : "ONE-WAY");
941 
942 		auth_printsub(&pointer[1], length - 1, buf, sizeof(buf));
943 		output_data("%s", buf);
944 		break;
945 
946 	    case TELQUAL_SEND:
947 		i = 2;
948 		output_data(" SEND ");
949 		while (i < length) {
950 		    if (AUTHTYPE_NAME_OK(pointer[i]))
951 			output_data("%s ", AUTHTYPE_NAME(pointer[i]));
952 		    else
953 			output_data("%d ", pointer[i]);
954 		    if (++i >= length) {
955 			output_data("(partial suboption??\?)");
956 			break;
957 		    }
958 		    output_data("%s|%s ",
959 			((pointer[i] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
960 							"CLIENT" : "SERVER",
961 			((pointer[i] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
962 							"MUTUAL" : "ONE-WAY");
963 		    ++i;
964 		}
965 		break;
966 
967 	    case TELQUAL_NAME:
968 		i = 2;
969 		output_data(" NAME \"");
970 		while (i < length) {
971 		    if (isprint(pointer[i]))
972 			output_data("%c", pointer[i++]);
973 		    else
974 			output_data("\"%03o\"",pointer[i++]);
975 		}
976 		output_data("\"");
977 		break;
978 
979 	    default:
980 		for (i = 2; i < length; i++)
981 		    output_data(" ?%d?", pointer[i]);
982 		break;
983 	    }
984 	    break;
985 #endif
986 
987 #ifdef	ENCRYPTION
988 	case TELOPT_ENCRYPT:
989 	    output_data("ENCRYPT");
990 	    if (length < 2) {
991 		output_data(" (empty suboption??\?)");
992 		break;
993 	    }
994 	    switch (pointer[1]) {
995 	    case ENCRYPT_START:
996 		output_data(" START");
997 		break;
998 
999 	    case ENCRYPT_END:
1000 		output_data(" END");
1001 		break;
1002 
1003 	    case ENCRYPT_REQSTART:
1004 		output_data(" REQUEST-START");
1005 		break;
1006 
1007 	    case ENCRYPT_REQEND:
1008 		output_data(" REQUEST-END");
1009 		break;
1010 
1011 	    case ENCRYPT_IS:
1012 	    case ENCRYPT_REPLY:
1013 		output_data(" %s ", (pointer[1] == ENCRYPT_IS) ?
1014 		    "IS" : "REPLY");
1015 		if (length < 3) {
1016 			output_data(" (partial suboption??\?)");
1017 			break;
1018 		}
1019 		if (ENCTYPE_NAME_OK(pointer[2]))
1020 			output_data("%s ", ENCTYPE_NAME(pointer[2]));
1021 		else
1022 			output_data(" %d (unknown)", pointer[2]);
1023 
1024 		encrypt_printsub(&pointer[1], length - 1, buf, sizeof(buf));
1025 		output_data("%s", buf);
1026 		break;
1027 
1028 	    case ENCRYPT_SUPPORT:
1029 		i = 2;
1030 		output_data(" SUPPORT ");
1031 		while (i < length) {
1032 			if (ENCTYPE_NAME_OK(pointer[i]))
1033 				output_data("%s ", ENCTYPE_NAME(pointer[i]));
1034 			else
1035 				output_data("%d ", pointer[i]);
1036 			i++;
1037 		}
1038 		break;
1039 
1040 	    case ENCRYPT_ENC_KEYID:
1041 		output_data(" ENC_KEYID");
1042 		goto encommon;
1043 
1044 	    case ENCRYPT_DEC_KEYID:
1045 		output_data(" DEC_KEYID");
1046 		goto encommon;
1047 
1048 	    default:
1049 		output_data(" %d (unknown)", pointer[1]);
1050 	    encommon:
1051 		for (i = 2; i < length; i++)
1052 			output_data(" %d", pointer[i]);
1053 		break;
1054 	    }
1055 	    break;
1056 #endif	/* ENCRYPTION */
1057 
1058 	default:
1059 	    if (TELOPT_OK(pointer[0]))
1060 		output_data("%s (unknown)", TELOPT(pointer[0]));
1061 	    else
1062 		output_data("%d (unknown)", pointer[i]);
1063 	    for (i = 1; i < length; i++)
1064 		output_data(" %d", pointer[i]);
1065 	    break;
1066 	}
1067 	output_data("\r\n");
1068 }
1069 
1070 /*
1071  * Dump a data buffer in hex and ascii to the output data stream.
1072  */
1073 	void
1074 printdata(tag, ptr, cnt)
1075 	register char *tag;
1076 	register char *ptr;
1077 	register int cnt;
1078 {
1079 	register int i;
1080 	char xbuf[30];
1081 
1082 	while (cnt) {
1083 		/* flush net output buffer if no room for new data) */
1084 		if ((&netobuf[BUFSIZ] - nfrontp) < 80) {
1085 			netflush();
1086 		}
1087 
1088 		/* add a line of output */
1089 		output_data("%s: ", tag);
1090 		for (i = 0; i < 20 && cnt; i++) {
1091 			output_data("%02x", *ptr);
1092 			if (isprint(*ptr)) {
1093 				xbuf[i] = *ptr;
1094 			} else {
1095 				xbuf[i] = '.';
1096 			}
1097 			if (i % 2)
1098 				output_data(" ");
1099 			cnt--;
1100 			ptr++;
1101 		}
1102 		xbuf[i] = '\0';
1103 		output_data(" %s\r\n", xbuf);
1104 	}
1105 }
1106 #endif /* DIAGNOSTICS */
1107