xref: /dragonfly/libexec/telnetd/utility.c (revision a3127495)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)utility.c	8.4 (Berkeley) 5/30/95
30  * $FreeBSD: src/crypto/telnet/telnetd/utility.c,v 1.5.2.4 2002/04/13 10:59:09 markm Exp $
31  */
32 
33 #if defined(__FreeBSD__) || defined(__DragonFly__)
34 #include <locale.h>
35 #include <sys/utsname.h>
36 #endif
37 #include <string.h>
38 #define PRINTOPTIONS
39 #include "telnetd.h"
40 
41 #ifdef	AUTHENTICATION
42 #include <libtelnet/auth.h>
43 #endif
44 #ifdef	ENCRYPTION
45 #include <libtelnet/encrypt.h>
46 #endif
47 
48 /*
49  * utility functions performing io related tasks
50  */
51 
52 /*
53  * ttloop
54  *
55  *	A small subroutine to flush the network output buffer, get some data
56  * from the network, and pass it through the telnet state machine.  We
57  * also flush the pty input buffer (by dropping its data) if it becomes
58  * too full.
59  */
60 
61 void
62 ttloop(void)
63 {
64 
65     DIAG(TD_REPORT, output_data("td: ttloop\r\n"));
66     if (nfrontp - nbackp > 0) {
67 	netflush();
68     }
69     ncc = read(net, netibuf, sizeof netibuf);
70     if (ncc < 0) {
71 	syslog(LOG_INFO, "ttloop:  read: %m");
72 	exit(1);
73     } else if (ncc == 0) {
74 	syslog(LOG_INFO, "ttloop:  peer died: %m");
75 	exit(1);
76     }
77     DIAG(TD_REPORT, output_data("td: ttloop read %d chars\r\n", ncc));
78     netip = netibuf;
79     telrcv();			/* state machine */
80     if (ncc > 0) {
81 	pfrontp = pbackp = ptyobuf;
82 	telrcv();
83     }
84 }  /* end of ttloop */
85 
86 /*
87  * Check a descriptor to see if out of band data exists on it.
88  */
89 int
90 stilloob(int s)
91 {
92     static struct timeval timeout = { 0, 0 };
93     fd_set	excepts;
94     int value;
95 
96     do {
97 	FD_ZERO(&excepts);
98 	FD_SET(s, &excepts);
99 	memset((char *)&timeout, 0, sizeof timeout);
100 	value = select(s+1, NULL, NULL, &excepts, &timeout);
101     } while ((value == -1) && (errno == EINTR));
102 
103     if (value < 0) {
104 	fatalperror(pty, "select");
105     }
106     if (FD_ISSET(s, &excepts)) {
107 	return 1;
108     } else {
109 	return 0;
110     }
111 }
112 
113 void
114 ptyflush(void)
115 {
116 	int n;
117 
118 	if ((n = pfrontp - pbackp) > 0) {
119 		DIAG(TD_REPORT | TD_PTYDATA,
120 		    output_data("td: ptyflush %d chars\r\n", n));
121 		DIAG(TD_PTYDATA, printdata("pd", pbackp, n));
122 		n = write(pty, pbackp, n);
123 	}
124 	if (n < 0) {
125 		if (errno == EWOULDBLOCK || errno == EINTR)
126 			return;
127 		cleanup(0);
128 	}
129 	pbackp += n;
130 	if (pbackp == pfrontp)
131 		pbackp = pfrontp = ptyobuf;
132 }
133 
134 /*
135  * nextitem()
136  *
137  *	Return the address of the next "item" in the TELNET data
138  * stream.  This will be the address of the next character if
139  * the current address is a user data character, or it will
140  * be the address of the character following the TELNET command
141  * if the current address is a TELNET IAC ("I Am a Command")
142  * character.
143  */
144 static char *
145 nextitem(char *current)
146 {
147     if ((*current&0xff) != IAC) {
148 	return current+1;
149     }
150     switch (*(current+1)&0xff) {
151     case DO:
152     case DONT:
153     case WILL:
154     case WONT:
155 	return current+3;
156     case SB:		/* loop forever looking for the SE */
157 	{
158 	    char *look = current+2;
159 
160 	    for (;;) {
161 		if ((*look++&0xff) == IAC) {
162 		    if ((*look++&0xff) == SE) {
163 			return look;
164 		    }
165 		}
166 	    }
167 	}
168     default:
169 	return current+2;
170     }
171 }  /* end of nextitem */
172 
173 /*
174  * netclear()
175  *
176  *	We are about to do a TELNET SYNCH operation.  Clear
177  * the path to the network.
178  *
179  *	Things are a bit tricky since we may have sent the first
180  * byte or so of a previous TELNET command into the network.
181  * So, we have to scan the network buffer from the beginning
182  * until we are up to where we want to be.
183  *
184  *	A side effect of what we do, just to keep things
185  * simple, is to clear the urgent data pointer.  The principal
186  * caller should be setting the urgent data pointer AFTER calling
187  * us in any case.
188  */
189 void
190 netclear(void)
191 {
192     char *thisitem, *next;
193     char *good;
194 #define	wewant(p)	((nfrontp > p) && ((*p&0xff) == IAC) && \
195 				((*(p+1)&0xff) != EC) && ((*(p+1)&0xff) != EL))
196 
197 #ifdef	ENCRYPTION
198     thisitem = nclearto > netobuf ? nclearto : netobuf;
199 #else	/* ENCRYPTION */
200     thisitem = netobuf;
201 #endif	/* ENCRYPTION */
202 
203     while ((next = nextitem(thisitem)) <= nbackp) {
204 	thisitem = next;
205     }
206 
207     /* Now, thisitem is first before/at boundary. */
208 
209 #ifdef	ENCRYPTION
210     good = nclearto > netobuf ? nclearto : netobuf;
211 #else	/* ENCRYPTION */
212     good = netobuf;	/* where the good bytes go */
213 #endif	/* ENCRYPTION */
214 
215     while (nfrontp > thisitem) {
216 	if (wewant(thisitem)) {
217 	    int length;
218 
219 	    next = thisitem;
220 	    do {
221 		next = nextitem(next);
222 	    } while (wewant(next) && (nfrontp > next));
223 	    length = next-thisitem;
224 	    memmove(good, thisitem, length);
225 	    good += length;
226 	    thisitem = next;
227 	} else {
228 	    thisitem = nextitem(thisitem);
229 	}
230     }
231 
232     nbackp = netobuf;
233     nfrontp = good;		/* next byte to be sent */
234     neturg = 0;
235 }  /* end of netclear */
236 
237 /*
238  *  netflush
239  *		Send as much data as possible to the network,
240  *	handling requests for urgent data.
241  */
242 void
243 netflush(void)
244 {
245     int n;
246     extern int not42;
247 
248     while ((n = nfrontp - nbackp) > 0) {
249 #if 0
250 	/* XXX This causes output_data() to recurse and die */
251 	DIAG(TD_REPORT, {
252 	    n += output_data("td: netflush %d chars\r\n", n);
253 	});
254 #endif
255 #ifdef	ENCRYPTION
256 	if (encrypt_output) {
257 		char *s = nclearto ? nclearto : nbackp;
258 		if (nfrontp - s > 0) {
259 			(*encrypt_output)((unsigned char *)s, nfrontp-s);
260 			nclearto = nfrontp;
261 		}
262 	}
263 #endif	/* ENCRYPTION */
264 	/*
265 	 * if no urgent data, or if the other side appears to be an
266 	 * old 4.2 client (and thus unable to survive TCP urgent data),
267 	 * write the entire buffer in non-OOB mode.
268 	 */
269 	if ((neturg == 0) || (not42 == 0)) {
270 	    n = write(net, nbackp, n);	/* normal write */
271 	} else {
272 	    n = neturg - nbackp;
273 	    /*
274 	     * In 4.2 (and 4.3) systems, there is some question about
275 	     * what byte in a sendOOB operation is the "OOB" data.
276 	     * To make ourselves compatible, we only send ONE byte
277 	     * out of band, the one WE THINK should be OOB (though
278 	     * we really have more the TCP philosophy of urgent data
279 	     * rather than the Unix philosophy of OOB data).
280 	     */
281 	    if (n > 1) {
282 		n = send(net, nbackp, n-1, 0);	/* send URGENT all by itself */
283 	    } else {
284 		n = send(net, nbackp, n, MSG_OOB);	/* URGENT data */
285 	    }
286 	}
287 	if (n == -1) {
288 	    if (errno == EWOULDBLOCK || errno == EINTR)
289 		continue;
290 	    cleanup(0);
291 	    /* NOTREACHED */
292 	}
293 	nbackp += n;
294 #ifdef	ENCRYPTION
295 	if (nbackp > nclearto)
296 	    nclearto = 0;
297 #endif	/* ENCRYPTION */
298 	if (nbackp >= neturg) {
299 	    neturg = 0;
300 	}
301 	if (nbackp == nfrontp) {
302 	    nbackp = nfrontp = netobuf;
303 #ifdef	ENCRYPTION
304 	    nclearto = 0;
305 #endif	/* ENCRYPTION */
306 	}
307     }
308     return;
309 }  /* end of netflush */
310 
311 
312 /*
313  * miscellaneous functions doing a variety of little jobs follow ...
314  */
315 
316 
317 void
318 fatal(int f, const char *msg)
319 {
320 	char buf[BUFSIZ];
321 
322 	(void) snprintf(buf, sizeof(buf), "telnetd: %s.\r\n", msg);
323 #ifdef	ENCRYPTION
324 	if (encrypt_output) {
325 		/*
326 		 * Better turn off encryption first....
327 		 * Hope it flushes...
328 		 */
329 		encrypt_send_end();
330 		netflush();
331 	}
332 #endif	/* ENCRYPTION */
333 	(void) write(f, buf, (int)strlen(buf));
334 	sleep(1);	/*XXX*/
335 	exit(1);
336 }
337 
338 void
339 fatalperror(int f, const char *msg)
340 {
341 	char buf[BUFSIZ];
342 
343 	(void) snprintf(buf, sizeof(buf), "%s: %s", msg, strerror(errno));
344 	fatal(f, buf);
345 }
346 
347 char editedhost[32];
348 
349 void
350 edithost(char *pat, char *host)
351 {
352 	char *res = editedhost;
353 
354 	if (!pat)
355 		pat = strdup("");
356 	while (*pat) {
357 		switch (*pat) {
358 
359 		case '#':
360 			if (*host)
361 				host++;
362 			break;
363 
364 		case '@':
365 			if (*host)
366 				*res++ = *host++;
367 			break;
368 
369 		default:
370 			*res++ = *pat;
371 			break;
372 		}
373 		if (res == &editedhost[sizeof editedhost - 1]) {
374 			*res = '\0';
375 			return;
376 		}
377 		pat++;
378 	}
379 	if (*host)
380 		(void) strncpy(res, host,
381 				sizeof editedhost - (res - editedhost) -1);
382 	else
383 		*res = '\0';
384 	editedhost[sizeof editedhost - 1] = '\0';
385 }
386 
387 static char *putlocation;
388 
389 static void
390 putstr(const char *s)
391 {
392 
393 	while (*s)
394 		putchr(*s++);
395 }
396 
397 void
398 putchr(int cc)
399 {
400 	*putlocation++ = cc;
401 }
402 
403 #if defined(__FreeBSD__) || defined(__DragonFly__)
404 static char fmtstr[] = { "%+" };
405 #else
406 static char fmtstr[] = { "%l:%M%P on %A, %d %B %Y" };
407 #endif
408 
409 void
410 putf(char *cp, char *where)
411 {
412 	char *slash;
413 	time_t t;
414 	char db[100];
415 #if defined(__FreeBSD__) || defined(__DragonFly__)
416 	static struct utsname kerninfo;
417 
418 	if (!*kerninfo.sysname)
419 		uname(&kerninfo);
420 #endif
421 
422 	putlocation = where;
423 
424 	while (*cp) {
425 		if (*cp =='\n') {
426 			putstr("\r\n");
427 			cp++;
428 			continue;
429 		} else if (*cp != '%') {
430 			putchr(*cp++);
431 			continue;
432 		}
433 		switch (*++cp) {
434 
435 		case 't':
436 #ifdef	STREAMSPTY
437 			/* names are like /dev/pts/2 -- we want pts/2 */
438 			slash = strchr(line+1, '/');
439 #else
440 			slash = strrchr(line, '/');
441 #endif
442 			if (slash == (char *) 0)
443 				putstr(line);
444 			else
445 				putstr(&slash[1]);
446 			break;
447 
448 		case 'h':
449 			putstr(editedhost);
450 			break;
451 
452 		case 'd':
453 #if defined(__FreeBSD__) || defined(__DragonFly__)
454 			setlocale(LC_TIME, "");
455 #endif
456 			(void)time(&t);
457 			(void)strftime(db, sizeof(db), fmtstr, localtime(&t));
458 			putstr(db);
459 			break;
460 
461 #if defined(__FreeBSD__) || defined(__DragonFly__)
462 		case 's':
463 			putstr(kerninfo.sysname);
464 			break;
465 
466 		case 'm':
467 			putstr(kerninfo.machine);
468 			break;
469 
470 		case 'r':
471 			putstr(kerninfo.release);
472 			break;
473 
474 		case 'v':
475 			putstr(kerninfo.version);
476 			break;
477 #endif
478 
479 		case '%':
480 			putchr('%');
481 			break;
482 		}
483 		cp++;
484 	}
485 }
486 
487 #ifdef DIAGNOSTICS
488 /*
489  * Print telnet options and commands in plain text, if possible.
490  */
491 void
492 printoption(const char *fmt, int option)
493 {
494 	if (TELOPT_OK(option))
495 		output_data("%s %s\r\n", fmt, TELOPT(option));
496 	else if (TELCMD_OK(option))
497 		output_data("%s %s\r\n", fmt, TELCMD(option));
498 	else
499 		output_data("%s %d\r\n", fmt, option);
500 	return;
501 }
502 
503 void
504 printsub(char direction, unsigned char *pointer, int length)
505 {
506     int i = 0;
507 
508 	if (!(diagnostic & TD_OPTIONS))
509 		return;
510 
511 	if (direction) {
512 	    output_data("td: %s suboption ",
513 					direction == '<' ? "recv" : "send");
514 	    if (length >= 3) {
515 		int j;
516 
517 		i = pointer[length-2];
518 		j = pointer[length-1];
519 
520 		if (i != IAC || j != SE) {
521 		    output_data("(terminated by ");
522 		    if (TELOPT_OK(i))
523 			output_data("%s ", TELOPT(i));
524 		    else if (TELCMD_OK(i))
525 			output_data("%s ", TELCMD(i));
526 		    else
527 			output_data("%d ", i);
528 		    if (TELOPT_OK(j))
529 			output_data("%s", TELOPT(j));
530 		    else if (TELCMD_OK(j))
531 			output_data("%s", TELCMD(j));
532 		    else
533 			output_data("%d", j);
534 		    output_data(", not IAC SE!) ");
535 		}
536 	    }
537 	    length -= 2;
538 	}
539 	if (length < 1) {
540 	    output_data("(Empty suboption??\?)");
541 	    return;
542 	}
543 	switch (pointer[0]) {
544 	case TELOPT_TTYPE:
545 	    output_data("TERMINAL-TYPE ");
546 	    switch (pointer[1]) {
547 	    case TELQUAL_IS:
548 		output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
549 		break;
550 	    case TELQUAL_SEND:
551 		output_data("SEND");
552 		break;
553 	    default:
554 		output_data(
555 				"- unknown qualifier %d (0x%x).",
556 				pointer[1], pointer[1]);
557 	    }
558 	    break;
559 	case TELOPT_TSPEED:
560 	    output_data("TERMINAL-SPEED");
561 	    if (length < 2) {
562 		output_data(" (empty suboption??\?)");
563 		break;
564 	    }
565 	    switch (pointer[1]) {
566 	    case TELQUAL_IS:
567 		output_data(" IS %.*s", length-2, (char *)pointer+2);
568 		break;
569 	    default:
570 		if (pointer[1] == 1)
571 		    output_data(" SEND");
572 		else
573 		    output_data(" %d (unknown)", pointer[1]);
574 		for (i = 2; i < length; i++) {
575 		    output_data(" ?%d?", pointer[i]);
576 		}
577 		break;
578 	    }
579 	    break;
580 
581 	case TELOPT_LFLOW:
582 	    output_data("TOGGLE-FLOW-CONTROL");
583 	    if (length < 2) {
584 		output_data(" (empty suboption??\?)");
585 		break;
586 	    }
587 	    switch (pointer[1]) {
588 	    case LFLOW_OFF:
589 		output_data(" OFF"); break;
590 	    case LFLOW_ON:
591 		output_data(" ON"); break;
592 	    case LFLOW_RESTART_ANY:
593 		output_data(" RESTART-ANY"); break;
594 	    case LFLOW_RESTART_XON:
595 		output_data(" RESTART-XON"); break;
596 	    default:
597 		output_data(" %d (unknown)", pointer[1]);
598 	    }
599 	    for (i = 2; i < length; i++) {
600 		output_data(" ?%d?", pointer[i]);
601 	    }
602 	    break;
603 
604 	case TELOPT_NAWS:
605 	    output_data("NAWS");
606 	    if (length < 2) {
607 		output_data(" (empty suboption??\?)");
608 		break;
609 	    }
610 	    if (length == 2) {
611 		output_data(" ?%d?", pointer[1]);
612 		break;
613 	    }
614 	    output_data(" %d %d (%d)",
615 		pointer[1], pointer[2],
616 		(int)((((unsigned int)pointer[1])<<8)|((unsigned int)pointer[2])));
617 	    if (length == 4) {
618 		output_data(" ?%d?", pointer[3]);
619 		break;
620 	    }
621 	    output_data(" %d %d (%d)",
622 		pointer[3], pointer[4],
623 		(int)((((unsigned int)pointer[3])<<8)|((unsigned int)pointer[4])));
624 	    for (i = 5; i < length; i++) {
625 		output_data(" ?%d?", pointer[i]);
626 	    }
627 	    break;
628 
629 	case TELOPT_LINEMODE:
630 	    output_data("LINEMODE ");
631 	    if (length < 2) {
632 		output_data(" (empty suboption??\?)");
633 		break;
634 	    }
635 	    switch (pointer[1]) {
636 	    case WILL:
637 		output_data("WILL ");
638 		goto common;
639 	    case WONT:
640 		output_data("WONT ");
641 		goto common;
642 	    case DO:
643 		output_data("DO ");
644 		goto common;
645 	    case DONT:
646 		output_data("DONT ");
647 	    common:
648 		if (length < 3) {
649 		    output_data("(no option??\?)");
650 		    break;
651 		}
652 		switch (pointer[2]) {
653 		case LM_FORWARDMASK:
654 		    output_data("Forward Mask");
655 		    for (i = 3; i < length; i++) {
656 			output_data(" %x", pointer[i]);
657 		    }
658 		    break;
659 		default:
660 		    output_data("%d (unknown)", pointer[2]);
661 		    for (i = 3; i < length; i++) {
662 			output_data(" %d", pointer[i]);
663 		    }
664 		    break;
665 		}
666 		break;
667 
668 	    case LM_SLC:
669 		output_data("SLC");
670 		for (i = 2; i < length - 2; i += 3) {
671 		    if (SLC_NAME_OK(pointer[i+SLC_FUNC]))
672 			output_data(" %s", SLC_NAME(pointer[i+SLC_FUNC]));
673 		    else
674 			output_data(" %d", pointer[i+SLC_FUNC]);
675 		    switch (pointer[i+SLC_FLAGS]&SLC_LEVELBITS) {
676 		    case SLC_NOSUPPORT:
677 			output_data(" NOSUPPORT"); break;
678 		    case SLC_CANTCHANGE:
679 			output_data(" CANTCHANGE"); break;
680 		    case SLC_VARIABLE:
681 			output_data(" VARIABLE"); break;
682 		    case SLC_DEFAULT:
683 			output_data(" DEFAULT"); break;
684 		    }
685 		    output_data("%s%s%s",
686 			pointer[i+SLC_FLAGS]&SLC_ACK ? "|ACK" : "",
687 			pointer[i+SLC_FLAGS]&SLC_FLUSHIN ? "|FLUSHIN" : "",
688 			pointer[i+SLC_FLAGS]&SLC_FLUSHOUT ? "|FLUSHOUT" : "");
689 		    if (pointer[i+SLC_FLAGS]& ~(SLC_ACK|SLC_FLUSHIN|
690 						SLC_FLUSHOUT| SLC_LEVELBITS)) {
691 			output_data("(0x%x)", pointer[i+SLC_FLAGS]);
692 		    }
693 		    output_data(" %d;", pointer[i+SLC_VALUE]);
694 		    if ((pointer[i+SLC_VALUE] == IAC) &&
695 			(pointer[i+SLC_VALUE+1] == IAC))
696 				i++;
697 		}
698 		for (; i < length; i++) {
699 		    output_data(" ?%d?", pointer[i]);
700 		}
701 		break;
702 
703 	    case LM_MODE:
704 		output_data("MODE ");
705 		if (length < 3) {
706 		    output_data("(no mode??\?)");
707 		    break;
708 		}
709 		{
710 		    char tbuf[32];
711 		    sprintf(tbuf, "%s%s%s%s%s",
712 			pointer[2]&MODE_EDIT ? "|EDIT" : "",
713 			pointer[2]&MODE_TRAPSIG ? "|TRAPSIG" : "",
714 			pointer[2]&MODE_SOFT_TAB ? "|SOFT_TAB" : "",
715 			pointer[2]&MODE_LIT_ECHO ? "|LIT_ECHO" : "",
716 			pointer[2]&MODE_ACK ? "|ACK" : "");
717 		    output_data("%s", tbuf[1] ? &tbuf[1] : "0");
718 		}
719 		if (pointer[2]&~(MODE_EDIT|MODE_TRAPSIG|MODE_ACK)) {
720 		    output_data(" (0x%x)", pointer[2]);
721 		}
722 		for (i = 3; i < length; i++) {
723 		    output_data(" ?0x%x?", pointer[i]);
724 		}
725 		break;
726 	    default:
727 		output_data("%d (unknown)", pointer[1]);
728 		for (i = 2; i < length; i++) {
729 		    output_data(" %d", pointer[i]);
730 		}
731 	    }
732 	    break;
733 
734 	case TELOPT_STATUS: {
735 	    const char *cp;
736 	    int j, k;
737 
738 	    output_data("STATUS");
739 
740 	    switch (pointer[1]) {
741 	    default:
742 		if (pointer[1] == TELQUAL_SEND)
743 		    output_data(" SEND");
744 		else
745 		    output_data(" %d (unknown)", pointer[1]);
746 		for (i = 2; i < length; i++) {
747 		    output_data(" ?%d?", pointer[i]);
748 		}
749 		break;
750 	    case TELQUAL_IS:
751 		output_data(" IS\r\n");
752 
753 		for (i = 2; i < length; i++) {
754 		    switch(pointer[i]) {
755 		    case DO:	cp = "DO"; goto common2;
756 		    case DONT:	cp = "DONT"; goto common2;
757 		    case WILL:	cp = "WILL"; goto common2;
758 		    case WONT:	cp = "WONT"; goto common2;
759 		    common2:
760 			i++;
761 			if (TELOPT_OK(pointer[i]))
762 			    output_data(" %s %s", cp, TELOPT(pointer[i]));
763 			else
764 			    output_data(" %s %d", cp, pointer[i]);
765 
766 			output_data("\r\n");
767 			break;
768 
769 		    case SB:
770 			output_data(" SB ");
771 			i++;
772 			j = k = i;
773 			while (j < length) {
774 			    if (pointer[j] == SE) {
775 				if (j+1 == length)
776 				    break;
777 				if (pointer[j+1] == SE)
778 				    j++;
779 				else
780 				    break;
781 			    }
782 			    pointer[k++] = pointer[j++];
783 			}
784 			printsub(0, &pointer[i], k - i);
785 			if (i < length) {
786 			    output_data(" SE");
787 			    i = j;
788 			} else
789 			    i = j - 1;
790 
791 			output_data("\r\n");
792 
793 			break;
794 
795 		    default:
796 			output_data(" %d", pointer[i]);
797 			break;
798 		    }
799 		}
800 		break;
801 	    }
802 	    break;
803 	  }
804 
805 	case TELOPT_XDISPLOC:
806 	    output_data("X-DISPLAY-LOCATION ");
807 	    switch (pointer[1]) {
808 	    case TELQUAL_IS:
809 		output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
810 		break;
811 	    case TELQUAL_SEND:
812 		output_data("SEND");
813 		break;
814 	    default:
815 		output_data("- unknown qualifier %d (0x%x).",
816 				pointer[1], pointer[1]);
817 	    }
818 	    break;
819 
820 	case TELOPT_NEW_ENVIRON:
821 	    output_data("NEW-ENVIRON ");
822 	    goto env_common1;
823 	case TELOPT_OLD_ENVIRON:
824 	    output_data("OLD-ENVIRON");
825 	env_common1:
826 	    switch (pointer[1]) {
827 	    case TELQUAL_IS:
828 		output_data("IS ");
829 		goto env_common;
830 	    case TELQUAL_SEND:
831 		output_data("SEND ");
832 		goto env_common;
833 	    case TELQUAL_INFO:
834 		output_data("INFO ");
835 	    env_common:
836 		{
837 		    int noquote = 2;
838 		    for (i = 2; i < length; i++ ) {
839 			switch (pointer[i]) {
840 			case NEW_ENV_VAR:
841 			    output_data("%s", "\" VAR " + noquote);
842 			    noquote = 2;
843 			    break;
844 
845 			case NEW_ENV_VALUE:
846 			    output_data("%s", "\" VALUE " + noquote);
847 			    noquote = 2;
848 			    break;
849 
850 			case ENV_ESC:
851 			    output_data("%s", "\" ESC " + noquote);
852 			    noquote = 2;
853 			    break;
854 
855 			case ENV_USERVAR:
856 			    output_data("%s", "\" USERVAR " + noquote);
857 			    noquote = 2;
858 			    break;
859 
860 			default:
861 			    if (isprint(pointer[i]) && pointer[i] != '"') {
862 				if (noquote) {
863 				    output_data("\"");
864 				    noquote = 0;
865 				}
866 				output_data("%c", pointer[i]);
867 			    } else {
868 				output_data("\" %03o " + noquote,
869 							pointer[i]);
870 				noquote = 2;
871 			    }
872 			    break;
873 			}
874 		    }
875 		    if (!noquote)
876 			output_data("\"");
877 		    break;
878 		}
879 	    }
880 	    break;
881 
882 #ifdef	AUTHENTICATION
883 	case TELOPT_AUTHENTICATION:
884 	    output_data("AUTHENTICATION");
885 
886 	    if (length < 2) {
887 		output_data(" (empty suboption??\?)");
888 		break;
889 	    }
890 	    switch (pointer[1]) {
891 	    case TELQUAL_REPLY:
892 	    case TELQUAL_IS:
893 		output_data(" %s ", (pointer[1] == TELQUAL_IS) ?
894 							"IS" : "REPLY");
895 		if (AUTHTYPE_NAME_OK(pointer[2]))
896 		    output_data("%s ", AUTHTYPE_NAME(pointer[2]));
897 		else
898 		    output_data("%d ", pointer[2]);
899 		if (length < 3) {
900 		    output_data("(partial suboption??\?)");
901 		    break;
902 		}
903 		output_data("%s|%s",
904 			((pointer[3] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
905 			"CLIENT" : "SERVER",
906 			((pointer[3] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
907 			"MUTUAL" : "ONE-WAY");
908 
909     		{
910 		    char buf[512];
911 		    auth_printsub(&pointer[1], length - 1, buf, sizeof(buf));
912 		    output_data("%s", buf);
913 		}
914 		break;
915 
916 	    case TELQUAL_SEND:
917 		i = 2;
918 		output_data(" SEND ");
919 		while (i < length) {
920 		    if (AUTHTYPE_NAME_OK(pointer[i]))
921 			output_data("%s ", AUTHTYPE_NAME(pointer[i]));
922 		    else
923 			output_data("%d ", pointer[i]);
924 		    if (++i >= length) {
925 			output_data("(partial suboption??\?)");
926 			break;
927 		    }
928 		    output_data("%s|%s ",
929 			((pointer[i] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
930 							"CLIENT" : "SERVER",
931 			((pointer[i] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
932 							"MUTUAL" : "ONE-WAY");
933 		    ++i;
934 		}
935 		break;
936 
937 	    case TELQUAL_NAME:
938 		output_data(" NAME \"%.*s\"", length - 2, pointer + 2);
939 		break;
940 
941 	    default:
942 		    for (i = 2; i < length; i++) {
943 			output_data(" ?%d?", pointer[i]);
944 		    }
945 		    break;
946 	    }
947 	    break;
948 #endif
949 
950 #ifdef	ENCRYPTION
951 	case TELOPT_ENCRYPT:
952 	    output_data("ENCRYPT");
953 	    if (length < 2) {
954 		output_data(" (empty suboption??\?)");
955 		break;
956 	    }
957 	    switch (pointer[1]) {
958 	    case ENCRYPT_START:
959 		output_data(" START");
960 		break;
961 
962 	    case ENCRYPT_END:
963 		output_data(" END");
964 		break;
965 
966 	    case ENCRYPT_REQSTART:
967 		output_data(" REQUEST-START");
968 		break;
969 
970 	    case ENCRYPT_REQEND:
971 		output_data(" REQUEST-END");
972 		break;
973 
974 	    case ENCRYPT_IS:
975 	    case ENCRYPT_REPLY:
976 		output_data(" %s ", (pointer[1] == ENCRYPT_IS) ?
977 							"IS" : "REPLY");
978 		if (length < 3) {
979 		    output_data(" (partial suboption??\?)");
980 		    break;
981 		}
982 		if (ENCTYPE_NAME_OK(pointer[2]))
983 		    output_data("%s ", ENCTYPE_NAME(pointer[2]));
984 		else
985 		    output_data(" %d (unknown)", pointer[2]);
986 
987 		{
988 		    char buf[512];
989 		    encrypt_printsub(&pointer[1], length - 1, buf, sizeof(buf));
990 		    output_data("%s", buf);
991 		}
992 		break;
993 
994 	    case ENCRYPT_SUPPORT:
995 		i = 2;
996 		output_data(" SUPPORT ");
997 		while (i < length) {
998 		    if (ENCTYPE_NAME_OK(pointer[i]))
999 			output_data("%s ", ENCTYPE_NAME(pointer[i]));
1000 		    else
1001 			output_data("%d ", pointer[i]);
1002 		    i++;
1003 		}
1004 		break;
1005 
1006 	    case ENCRYPT_ENC_KEYID:
1007 		output_data(" ENC_KEYID");
1008 		goto encommon;
1009 
1010 	    case ENCRYPT_DEC_KEYID:
1011 		output_data(" DEC_KEYID");
1012 		goto encommon;
1013 
1014 	    default:
1015 		output_data(" %d (unknown)", pointer[1]);
1016 	    encommon:
1017 		for (i = 2; i < length; i++) {
1018 		    output_data(" %d", pointer[i]);
1019 		}
1020 		break;
1021 	    }
1022 	    break;
1023 #endif	/* ENCRYPTION */
1024 
1025 	default:
1026 	    if (TELOPT_OK(pointer[0]))
1027 		output_data("%s (unknown)", TELOPT(pointer[0]));
1028 	    else
1029 		output_data("%d (unknown)", pointer[i]);
1030 	    for (i = 1; i < length; i++) {
1031 		output_data(" %d", pointer[i]);
1032 	    }
1033 	    break;
1034 	}
1035 	output_data("\r\n");
1036 }
1037 
1038 /*
1039  * Dump a data buffer in hex and ascii to the output data stream.
1040  */
1041 void
1042 printdata(const char *tag, char *ptr, int cnt)
1043 {
1044 	int i;
1045 	char xbuf[30];
1046 
1047 	while (cnt) {
1048 		/* flush net output buffer if no room for new data) */
1049 		if ((&netobuf[BUFSIZ] - nfrontp) < 80) {
1050 			netflush();
1051 		}
1052 
1053 		/* add a line of output */
1054 		output_data("%s: ", tag);
1055 		for (i = 0; i < 20 && cnt; i++) {
1056 			output_data("%02x", *ptr);
1057 			if (isprint(*ptr)) {
1058 				xbuf[i] = *ptr;
1059 			} else {
1060 				xbuf[i] = '.';
1061 			}
1062 			if (i % 2) {
1063 				output_data(" ");
1064 			}
1065 			cnt--;
1066 			ptr++;
1067 		}
1068 		xbuf[i] = '\0';
1069 		output_data(" %s\r\n", xbuf );
1070 	}
1071 }
1072 #endif /* DIAGNOSTICS */
1073