xref: /haiku/src/bin/network/telnetd/utility.c (revision 83b1a68c52ba3e0e8796282759f694b7fdddf06d)
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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if 0
35 #ifndef lint
36 static const char sccsid[] = "@(#)utility.c	8.4 (Berkeley) 5/30/95";
37 #endif /* not lint */
38 #endif
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD: src/contrib/telnet/telnetd/utility.c,v 1.13 2003/05/04 02:54:49 obrien Exp $");
41 
42 #ifdef __FreeBSD__
43 #include <locale.h>
44 #include <sys/utsname.h>
45 #endif
46 #include <string.h>
47 #define PRINTOPTIONS
48 #include "telnetd.h"
49 
50 #ifdef	AUTHENTICATION
51 #include <libtelnet/auth.h>
52 #endif
53 #ifdef	ENCRYPTION
54 #include <libtelnet/encrypt.h>
55 #endif
56 
57 /*
58  * utility functions performing io related tasks
59  */
60 
61 /*
62  * ttloop
63  *
64  *	A small subroutine to flush the network output buffer, get some data
65  * from the network, and pass it through the telnet state machine.  We
66  * also flush the pty input buffer (by dropping its data) if it becomes
67  * too full.
68  */
69 
70     void
71 ttloop()
72 {
73 
74     DIAG(TD_REPORT, output_data("td: ttloop\r\n"));
75     if (nfrontp - nbackp > 0) {
76 	netflush();
77     }
78     ncc = read(net, netibuf, sizeof netibuf);
79     if (ncc < 0) {
80 	syslog(LOG_INFO, "ttloop:  read: %m");
81 	exit(1);
82     } else if (ncc == 0) {
83 	syslog(LOG_INFO, "ttloop:  peer died: %m");
84 	exit(1);
85     }
86     DIAG(TD_REPORT, output_data("td: ttloop read %d chars\r\n", ncc));
87     netip = netibuf;
88     telrcv();			/* state machine */
89     if (ncc > 0) {
90 	pfrontp = pbackp = ptyobuf;
91 	telrcv();
92     }
93 }  /* end of ttloop */
94 
95 /*
96  * Check a descriptor to see if out of band data exists on it.
97  */
98 int
99 stilloob(int s)
100 {
101     static struct timeval timeout = { 0, 0 };
102     fd_set	excepts;
103     int value;
104 
105     do {
106 	FD_ZERO(&excepts);
107 	FD_SET(s, &excepts);
108 	memset((char *)&timeout, 0, sizeof timeout);
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(void)
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 static char *
154 nextitem(char *current)
155 {
156     if ((*current&0xff) != IAC) {
157 	return current+1;
158     }
159     switch (*(current+1)&0xff) {
160     case DO:
161     case DONT:
162     case WILL:
163     case WONT:
164 	return current+3;
165     case SB:		/* loop forever looking for the SE */
166 	{
167 	    char *look = current+2;
168 
169 	    for (;;) {
170 		if ((*look++&0xff) == IAC) {
171 		    if ((*look++&0xff) == SE) {
172 			return look;
173 		    }
174 		}
175 	    }
176 	}
177     default:
178 	return current+2;
179     }
180 }  /* end of nextitem */
181 
182 /*
183  * netclear()
184  *
185  *	We are about to do a TELNET SYNCH operation.  Clear
186  * the path to the network.
187  *
188  *	Things are a bit tricky since we may have sent the first
189  * byte or so of a previous TELNET command into the network.
190  * So, we have to scan the network buffer from the beginning
191  * until we are up to where we want to be.
192  *
193  *	A side effect of what we do, just to keep things
194  * simple, is to clear the urgent data pointer.  The principal
195  * caller should be setting the urgent data pointer AFTER calling
196  * us in any case.
197  */
198 void
199 netclear(void)
200 {
201     char *thisitem, *next;
202     char *good;
203 #define	wewant(p)	((nfrontp > p) && ((*p&0xff) == IAC) && \
204 				((*(p+1)&0xff) != EC) && ((*(p+1)&0xff) != EL))
205 
206 #ifdef	ENCRYPTION
207     thisitem = nclearto > netobuf ? nclearto : netobuf;
208 #else	/* ENCRYPTION */
209     thisitem = netobuf;
210 #endif	/* ENCRYPTION */
211 
212     while ((next = nextitem(thisitem)) <= nbackp) {
213 	thisitem = next;
214     }
215 
216     /* Now, thisitem is first before/at boundary. */
217 
218 #ifdef	ENCRYPTION
219     good = nclearto > netobuf ? nclearto : netobuf;
220 #else	/* ENCRYPTION */
221     good = netobuf;	/* where the good bytes go */
222 #endif	/* ENCRYPTION */
223 
224     while (nfrontp > thisitem) {
225 	if (wewant(thisitem)) {
226 	    int length;
227 
228 	    next = thisitem;
229 	    do {
230 		next = nextitem(next);
231 	    } while (wewant(next) && (nfrontp > next));
232 	    length = next-thisitem;
233 	    memmove(good, thisitem, length);
234 	    good += length;
235 	    thisitem = next;
236 	} else {
237 	    thisitem = nextitem(thisitem);
238 	}
239     }
240 
241     nbackp = netobuf;
242     nfrontp = good;		/* next byte to be sent */
243     neturg = 0;
244 }  /* end of netclear */
245 
246 /*
247  *  netflush
248  *		Send as much data as possible to the network,
249  *	handling requests for urgent data.
250  */
251 void
252 netflush(void)
253 {
254     int n;
255     extern int not42;
256 
257     while ((n = nfrontp - nbackp) > 0) {
258 #if 0
259 	/* XXX This causes output_data() to recurse and die */
260 	DIAG(TD_REPORT, {
261 	    n += output_data("td: netflush %d chars\r\n", n);
262 	});
263 #endif
264 #ifdef	ENCRYPTION
265 	if (encrypt_output) {
266 		char *s = nclearto ? nclearto : nbackp;
267 		if (nfrontp - s > 0) {
268 			(*encrypt_output)((unsigned char *)s, nfrontp-s);
269 			nclearto = nfrontp;
270 		}
271 	}
272 #endif	/* ENCRYPTION */
273 	/*
274 	 * if no urgent data, or if the other side appears to be an
275 	 * old 4.2 client (and thus unable to survive TCP urgent data),
276 	 * write the entire buffer in non-OOB mode.
277 	 */
278 	if ((neturg == 0) || (not42 == 0)) {
279 	    n = write(net, nbackp, n);	/* normal write */
280 	} else {
281 	    n = neturg - nbackp;
282 	    /*
283 	     * In 4.2 (and 4.3) systems, there is some question about
284 	     * what byte in a sendOOB operation is the "OOB" data.
285 	     * To make ourselves compatible, we only send ONE byte
286 	     * out of band, the one WE THINK should be OOB (though
287 	     * we really have more the TCP philosophy of urgent data
288 	     * rather than the Unix philosophy of OOB data).
289 	     */
290 	    if (n > 1) {
291 		n = send(net, nbackp, n-1, 0);	/* send URGENT all by itself */
292 	    } else {
293 		n = send(net, nbackp, n, MSG_OOB);	/* URGENT data */
294 	    }
295 	}
296 	if (n == -1) {
297 	    if (errno == EWOULDBLOCK || errno == EINTR)
298 		continue;
299 	    cleanup(0);
300 	    /* NOTREACHED */
301 	}
302 	nbackp += n;
303 #ifdef	ENCRYPTION
304 	if (nbackp > nclearto)
305 	    nclearto = 0;
306 #endif	/* ENCRYPTION */
307 	if (nbackp >= neturg) {
308 	    neturg = 0;
309 	}
310 	if (nbackp == nfrontp) {
311 	    nbackp = nfrontp = netobuf;
312 #ifdef	ENCRYPTION
313 	    nclearto = 0;
314 #endif	/* ENCRYPTION */
315 	}
316     }
317     return;
318 }  /* end of netflush */
319 
320 
321 /*
322  * miscellaneous functions doing a variety of little jobs follow ...
323  */
324 
325 
326 void
327 fatal(int f, const char *msg)
328 {
329 	char buf[BUFSIZ];
330 
331 	(void) snprintf(buf, sizeof(buf), "telnetd: %s.\r\n", msg);
332 #ifdef	ENCRYPTION
333 	if (encrypt_output) {
334 		/*
335 		 * Better turn off encryption first....
336 		 * Hope it flushes...
337 		 */
338 		encrypt_send_end();
339 		netflush();
340 	}
341 #endif	/* ENCRYPTION */
342 	(void) write(f, buf, (int)strlen(buf));
343 	sleep(1);	/*XXX*/
344 	exit(1);
345 }
346 
347 void
348 fatalperror(int f, const char *msg)
349 {
350 	char buf[BUFSIZ];
351 
352 	(void) snprintf(buf, sizeof(buf), "%s: %s", msg, strerror(errno));
353 	fatal(f, buf);
354 }
355 
356 char editedhost[32];
357 
358 void
359 edithost(char *pat, char *host)
360 {
361 	char *res = editedhost;
362 
363 	if (!pat)
364 		pat = strdup("");
365 	while (*pat) {
366 		switch (*pat) {
367 
368 		case '#':
369 			if (*host)
370 				host++;
371 			break;
372 
373 		case '@':
374 			if (*host)
375 				*res++ = *host++;
376 			break;
377 
378 		default:
379 			*res++ = *pat;
380 			break;
381 		}
382 		if (res == &editedhost[sizeof editedhost - 1]) {
383 			*res = '\0';
384 			return;
385 		}
386 		pat++;
387 	}
388 	if (*host)
389 		(void) strncpy(res, host,
390 				sizeof editedhost - (res - editedhost) -1);
391 	else
392 		*res = '\0';
393 	editedhost[sizeof editedhost - 1] = '\0';
394 }
395 
396 static char *putlocation;
397 
398 static void
399 putstr(const char *s)
400 {
401 
402 	while (*s)
403 		putchr(*s++);
404 }
405 
406 void
407 putchr(int cc)
408 {
409 	*putlocation++ = cc;
410 }
411 
412 #ifdef __FreeBSD__
413 static char fmtstr[] = { "%+" };
414 #else
415 static char fmtstr[] = { "%l:%M%P on %A, %d %B %Y" };
416 #endif
417 
418 void
419 putf(char *cp, char *where)
420 {
421 	char *slash;
422 	time_t t;
423 	char db[100];
424 #ifdef __FreeBSD__
425 	static struct utsname kerninfo;
426 
427 	if (!*kerninfo.sysname)
428 		uname(&kerninfo);
429 #endif
430 
431 	putlocation = where;
432 
433 	while (*cp) {
434 		if (*cp =='\n') {
435 			putstr("\r\n");
436 			cp++;
437 			continue;
438 		} else if (*cp != '%') {
439 			putchr(*cp++);
440 			continue;
441 		}
442 		switch (*++cp) {
443 
444 		case 't':
445 #ifdef	STREAMSPTY
446 			/* names are like /dev/pts/2 -- we want pts/2 */
447 			slash = strchr(line+1, '/');
448 #else
449 			slash = strrchr(line, '/');
450 #endif
451 			if (slash == (char *) 0)
452 				putstr(line);
453 			else
454 				putstr(&slash[1]);
455 			break;
456 
457 		case 'h':
458 			putstr(editedhost);
459 			break;
460 
461 		case 'd':
462 #ifdef __FreeBSD__
463 			setlocale(LC_TIME, "");
464 #endif
465 			(void)time(&t);
466 			(void)strftime(db, sizeof(db), fmtstr, localtime(&t));
467 			putstr(db);
468 			break;
469 
470 #ifdef __FreeBSD__
471 		case 's':
472 			putstr(kerninfo.sysname);
473 			break;
474 
475 		case 'm':
476 			putstr(kerninfo.machine);
477 			break;
478 
479 		case 'r':
480 			putstr(kerninfo.release);
481 			break;
482 
483 		case 'v':
484 			putstr(kerninfo.version);
485 			break;
486 #endif
487 
488 		case '%':
489 			putchr('%');
490 			break;
491 		}
492 		cp++;
493 	}
494 }
495 
496 #ifdef DIAGNOSTICS
497 /*
498  * Print telnet options and commands in plain text, if possible.
499  */
500 void
501 printoption(const char *fmt, int option)
502 {
503 	if (TELOPT_OK(option))
504 		output_data("%s %s\r\n", fmt, TELOPT(option));
505 	else if (TELCMD_OK(option))
506 		output_data("%s %s\r\n", fmt, TELCMD(option));
507 	else
508 		output_data("%s %d\r\n", fmt, option);
509 	return;
510 }
511 
512 void
513 printsub(char direction, unsigned char *pointer, int length)
514 {
515     int i = 0;
516 
517 	if (!(diagnostic & TD_OPTIONS))
518 		return;
519 
520 	if (direction) {
521 	    output_data("td: %s suboption ",
522 					direction == '<' ? "recv" : "send");
523 	    if (length >= 3) {
524 		int j;
525 
526 		i = pointer[length-2];
527 		j = pointer[length-1];
528 
529 		if (i != IAC || j != SE) {
530 		    output_data("(terminated by ");
531 		    if (TELOPT_OK(i))
532 			output_data("%s ", TELOPT(i));
533 		    else if (TELCMD_OK(i))
534 			output_data("%s ", TELCMD(i));
535 		    else
536 			output_data("%d ", i);
537 		    if (TELOPT_OK(j))
538 			output_data("%s", TELOPT(j));
539 		    else if (TELCMD_OK(j))
540 			output_data("%s", TELCMD(j));
541 		    else
542 			output_data("%d", j);
543 		    output_data(", not IAC SE!) ");
544 		}
545 	    }
546 	    length -= 2;
547 	}
548 	if (length < 1) {
549 	    output_data("(Empty suboption??\?)");
550 	    return;
551 	}
552 	switch (pointer[0]) {
553 	case TELOPT_TTYPE:
554 	    output_data("TERMINAL-TYPE ");
555 	    switch (pointer[1]) {
556 	    case TELQUAL_IS:
557 		output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
558 		break;
559 	    case TELQUAL_SEND:
560 		output_data("SEND");
561 		break;
562 	    default:
563 		output_data(
564 				"- unknown qualifier %d (0x%x).",
565 				pointer[1], pointer[1]);
566 	    }
567 	    break;
568 	case TELOPT_TSPEED:
569 	    output_data("TERMINAL-SPEED");
570 	    if (length < 2) {
571 		output_data(" (empty suboption??\?)");
572 		break;
573 	    }
574 	    switch (pointer[1]) {
575 	    case TELQUAL_IS:
576 		output_data(" IS %.*s", length-2, (char *)pointer+2);
577 		break;
578 	    default:
579 		if (pointer[1] == 1)
580 		    output_data(" SEND");
581 		else
582 		    output_data(" %d (unknown)", pointer[1]);
583 		for (i = 2; i < length; i++) {
584 		    output_data(" ?%d?", pointer[i]);
585 		}
586 		break;
587 	    }
588 	    break;
589 
590 	case TELOPT_LFLOW:
591 	    output_data("TOGGLE-FLOW-CONTROL");
592 	    if (length < 2) {
593 		output_data(" (empty suboption??\?)");
594 		break;
595 	    }
596 	    switch (pointer[1]) {
597 	    case LFLOW_OFF:
598 		output_data(" OFF"); break;
599 	    case LFLOW_ON:
600 		output_data(" ON"); break;
601 	    case LFLOW_RESTART_ANY:
602 		output_data(" RESTART-ANY"); break;
603 	    case LFLOW_RESTART_XON:
604 		output_data(" RESTART-XON"); break;
605 	    default:
606 		output_data(" %d (unknown)", pointer[1]);
607 	    }
608 	    for (i = 2; i < length; i++) {
609 		output_data(" ?%d?", pointer[i]);
610 	    }
611 	    break;
612 
613 	case TELOPT_NAWS:
614 	    output_data("NAWS");
615 	    if (length < 2) {
616 		output_data(" (empty suboption??\?)");
617 		break;
618 	    }
619 	    if (length == 2) {
620 		output_data(" ?%d?", pointer[1]);
621 		break;
622 	    }
623 	    output_data(" %d %d (%d)",
624 		pointer[1], pointer[2],
625 		(int)((((unsigned int)pointer[1])<<8)|((unsigned int)pointer[2])));
626 	    if (length == 4) {
627 		output_data(" ?%d?", pointer[3]);
628 		break;
629 	    }
630 	    output_data(" %d %d (%d)",
631 		pointer[3], pointer[4],
632 		(int)((((unsigned int)pointer[3])<<8)|((unsigned int)pointer[4])));
633 	    for (i = 5; i < length; i++) {
634 		output_data(" ?%d?", pointer[i]);
635 	    }
636 	    break;
637 
638 	case TELOPT_LINEMODE:
639 	    output_data("LINEMODE ");
640 	    if (length < 2) {
641 		output_data(" (empty suboption??\?)");
642 		break;
643 	    }
644 	    switch (pointer[1]) {
645 	    case WILL:
646 		output_data("WILL ");
647 		goto common;
648 	    case WONT:
649 		output_data("WONT ");
650 		goto common;
651 	    case DO:
652 		output_data("DO ");
653 		goto common;
654 	    case DONT:
655 		output_data("DONT ");
656 	    common:
657 		if (length < 3) {
658 		    output_data("(no option??\?)");
659 		    break;
660 		}
661 		switch (pointer[2]) {
662 		case LM_FORWARDMASK:
663 		    output_data("Forward Mask");
664 		    for (i = 3; i < length; i++) {
665 			output_data(" %x", pointer[i]);
666 		    }
667 		    break;
668 		default:
669 		    output_data("%d (unknown)", pointer[2]);
670 		    for (i = 3; i < length; i++) {
671 			output_data(" %d", pointer[i]);
672 		    }
673 		    break;
674 		}
675 		break;
676 
677 	    case LM_SLC:
678 		output_data("SLC");
679 		for (i = 2; i < length - 2; i += 3) {
680 		    if (SLC_NAME_OK(pointer[i+SLC_FUNC]))
681 			output_data(" %s", SLC_NAME(pointer[i+SLC_FUNC]));
682 		    else
683 			output_data(" %d", pointer[i+SLC_FUNC]);
684 		    switch (pointer[i+SLC_FLAGS]&SLC_LEVELBITS) {
685 		    case SLC_NOSUPPORT:
686 			output_data(" NOSUPPORT"); break;
687 		    case SLC_CANTCHANGE:
688 			output_data(" CANTCHANGE"); break;
689 		    case SLC_VARIABLE:
690 			output_data(" VARIABLE"); break;
691 		    case SLC_DEFAULT:
692 			output_data(" DEFAULT"); break;
693 		    }
694 		    output_data("%s%s%s",
695 			pointer[i+SLC_FLAGS]&SLC_ACK ? "|ACK" : "",
696 			pointer[i+SLC_FLAGS]&SLC_FLUSHIN ? "|FLUSHIN" : "",
697 			pointer[i+SLC_FLAGS]&SLC_FLUSHOUT ? "|FLUSHOUT" : "");
698 		    if (pointer[i+SLC_FLAGS]& ~(SLC_ACK|SLC_FLUSHIN|
699 						SLC_FLUSHOUT| SLC_LEVELBITS)) {
700 			output_data("(0x%x)", pointer[i+SLC_FLAGS]);
701 		    }
702 		    output_data(" %d;", pointer[i+SLC_VALUE]);
703 		    if ((pointer[i+SLC_VALUE] == IAC) &&
704 			(pointer[i+SLC_VALUE+1] == IAC))
705 				i++;
706 		}
707 		for (; i < length; i++) {
708 		    output_data(" ?%d?", pointer[i]);
709 		}
710 		break;
711 
712 	    case LM_MODE:
713 		output_data("MODE ");
714 		if (length < 3) {
715 		    output_data("(no mode??\?)");
716 		    break;
717 		}
718 		{
719 		    char tbuf[32];
720 		    sprintf(tbuf, "%s%s%s%s%s",
721 			pointer[2]&MODE_EDIT ? "|EDIT" : "",
722 			pointer[2]&MODE_TRAPSIG ? "|TRAPSIG" : "",
723 			pointer[2]&MODE_SOFT_TAB ? "|SOFT_TAB" : "",
724 			pointer[2]&MODE_LIT_ECHO ? "|LIT_ECHO" : "",
725 			pointer[2]&MODE_ACK ? "|ACK" : "");
726 		    output_data("%s", tbuf[1] ? &tbuf[1] : "0");
727 		}
728 		if (pointer[2]&~(MODE_EDIT|MODE_TRAPSIG|MODE_ACK)) {
729 		    output_data(" (0x%x)", pointer[2]);
730 		}
731 		for (i = 3; i < length; i++) {
732 		    output_data(" ?0x%x?", pointer[i]);
733 		}
734 		break;
735 	    default:
736 		output_data("%d (unknown)", pointer[1]);
737 		for (i = 2; i < length; i++) {
738 		    output_data(" %d", pointer[i]);
739 		}
740 	    }
741 	    break;
742 
743 	case TELOPT_STATUS: {
744 	    const char *cp;
745 	    int j, k;
746 
747 	    output_data("STATUS");
748 
749 	    switch (pointer[1]) {
750 	    default:
751 		if (pointer[1] == TELQUAL_SEND)
752 		    output_data(" SEND");
753 		else
754 		    output_data(" %d (unknown)", pointer[1]);
755 		for (i = 2; i < length; i++) {
756 		    output_data(" ?%d?", pointer[i]);
757 		}
758 		break;
759 	    case TELQUAL_IS:
760 		output_data(" IS\r\n");
761 
762 		for (i = 2; i < length; i++) {
763 		    switch(pointer[i]) {
764 		    case DO:	cp = "DO"; goto common2;
765 		    case DONT:	cp = "DONT"; goto common2;
766 		    case WILL:	cp = "WILL"; goto common2;
767 		    case WONT:	cp = "WONT"; goto common2;
768 		    common2:
769 			i++;
770 			if (TELOPT_OK(pointer[i]))
771 			    output_data(" %s %s", cp, TELOPT(pointer[i]));
772 			else
773 			    output_data(" %s %d", cp, pointer[i]);
774 
775 			output_data("\r\n");
776 			break;
777 
778 		    case SB:
779 			output_data(" SB ");
780 			i++;
781 			j = k = i;
782 			while (j < length) {
783 			    if (pointer[j] == SE) {
784 				if (j+1 == length)
785 				    break;
786 				if (pointer[j+1] == SE)
787 				    j++;
788 				else
789 				    break;
790 			    }
791 			    pointer[k++] = pointer[j++];
792 			}
793 			printsub(0, &pointer[i], k - i);
794 			if (i < length) {
795 			    output_data(" SE");
796 			    i = j;
797 			} else
798 			    i = j - 1;
799 
800 			output_data("\r\n");
801 
802 			break;
803 
804 		    default:
805 			output_data(" %d", pointer[i]);
806 			break;
807 		    }
808 		}
809 		break;
810 	    }
811 	    break;
812 	  }
813 
814 	case TELOPT_XDISPLOC:
815 	    output_data("X-DISPLAY-LOCATION ");
816 	    switch (pointer[1]) {
817 	    case TELQUAL_IS:
818 		output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
819 		break;
820 	    case TELQUAL_SEND:
821 		output_data("SEND");
822 		break;
823 	    default:
824 		output_data("- unknown qualifier %d (0x%x).",
825 				pointer[1], pointer[1]);
826 	    }
827 	    break;
828 
829 	case TELOPT_NEW_ENVIRON:
830 	    output_data("NEW-ENVIRON ");
831 	    goto env_common1;
832 	case TELOPT_OLD_ENVIRON:
833 	    output_data("OLD-ENVIRON");
834 	env_common1:
835 	    switch (pointer[1]) {
836 	    case TELQUAL_IS:
837 		output_data("IS ");
838 		goto env_common;
839 	    case TELQUAL_SEND:
840 		output_data("SEND ");
841 		goto env_common;
842 	    case TELQUAL_INFO:
843 		output_data("INFO ");
844 	    env_common:
845 		{
846 		    int noquote = 2;
847 		    for (i = 2; i < length; i++ ) {
848 			switch (pointer[i]) {
849 			case NEW_ENV_VAR:
850 			    output_data("\" VAR " + noquote);
851 			    noquote = 2;
852 			    break;
853 
854 			case NEW_ENV_VALUE:
855 			    output_data("\" VALUE " + noquote);
856 			    noquote = 2;
857 			    break;
858 
859 			case ENV_ESC:
860 			    output_data("\" ESC " + noquote);
861 			    noquote = 2;
862 			    break;
863 
864 			case ENV_USERVAR:
865 			    output_data("\" USERVAR " + noquote);
866 			    noquote = 2;
867 			    break;
868 
869 			default:
870 			    if (isprint(pointer[i]) && pointer[i] != '"') {
871 				if (noquote) {
872 				    output_data("\"");
873 				    noquote = 0;
874 				}
875 				output_data("%c", pointer[i]);
876 			    } else {
877 				output_data("\" %03o " + noquote,
878 							pointer[i]);
879 				noquote = 2;
880 			    }
881 			    break;
882 			}
883 		    }
884 		    if (!noquote)
885 			output_data("\"");
886 		    break;
887 		}
888 	    }
889 	    break;
890 
891 #ifdef	AUTHENTICATION
892 	case TELOPT_AUTHENTICATION:
893 	    output_data("AUTHENTICATION");
894 
895 	    if (length < 2) {
896 		output_data(" (empty suboption??\?)");
897 		break;
898 	    }
899 	    switch (pointer[1]) {
900 	    case TELQUAL_REPLY:
901 	    case TELQUAL_IS:
902 		output_data(" %s ", (pointer[1] == TELQUAL_IS) ?
903 							"IS" : "REPLY");
904 		if (AUTHTYPE_NAME_OK(pointer[2]))
905 		    output_data("%s ", AUTHTYPE_NAME(pointer[2]));
906 		else
907 		    output_data("%d ", pointer[2]);
908 		if (length < 3) {
909 		    output_data("(partial suboption??\?)");
910 		    break;
911 		}
912 		output_data("%s|%s",
913 			((pointer[3] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
914 			"CLIENT" : "SERVER",
915 			((pointer[3] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
916 			"MUTUAL" : "ONE-WAY");
917 
918     		{
919 		    char buf[512];
920 		    auth_printsub(&pointer[1], length - 1, buf, sizeof(buf));
921 		    output_data("%s", buf);
922 		}
923 		break;
924 
925 	    case TELQUAL_SEND:
926 		i = 2;
927 		output_data(" SEND ");
928 		while (i < length) {
929 		    if (AUTHTYPE_NAME_OK(pointer[i]))
930 			output_data("%s ", AUTHTYPE_NAME(pointer[i]));
931 		    else
932 			output_data("%d ", pointer[i]);
933 		    if (++i >= length) {
934 			output_data("(partial suboption??\?)");
935 			break;
936 		    }
937 		    output_data("%s|%s ",
938 			((pointer[i] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
939 							"CLIENT" : "SERVER",
940 			((pointer[i] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
941 							"MUTUAL" : "ONE-WAY");
942 		    ++i;
943 		}
944 		break;
945 
946 	    case TELQUAL_NAME:
947 		output_data(" NAME \"%.*s\"", length - 2, pointer + 2);
948 		break;
949 
950 	    default:
951 		    for (i = 2; i < length; i++) {
952 			output_data(" ?%d?", pointer[i]);
953 		    }
954 		    break;
955 	    }
956 	    break;
957 #endif
958 
959 #ifdef	ENCRYPTION
960 	case TELOPT_ENCRYPT:
961 	    output_data("ENCRYPT");
962 	    if (length < 2) {
963 		output_data(" (empty suboption??\?)");
964 		break;
965 	    }
966 	    switch (pointer[1]) {
967 	    case ENCRYPT_START:
968 		output_data(" START");
969 		break;
970 
971 	    case ENCRYPT_END:
972 		output_data(" END");
973 		break;
974 
975 	    case ENCRYPT_REQSTART:
976 		output_data(" REQUEST-START");
977 		break;
978 
979 	    case ENCRYPT_REQEND:
980 		output_data(" REQUEST-END");
981 		break;
982 
983 	    case ENCRYPT_IS:
984 	    case ENCRYPT_REPLY:
985 		output_data(" %s ", (pointer[1] == ENCRYPT_IS) ?
986 							"IS" : "REPLY");
987 		if (length < 3) {
988 		    output_data(" (partial suboption??\?)");
989 		    break;
990 		}
991 		if (ENCTYPE_NAME_OK(pointer[2]))
992 		    output_data("%s ", ENCTYPE_NAME(pointer[2]));
993 		else
994 		    output_data(" %d (unknown)", pointer[2]);
995 
996 		{
997 		    char buf[512];
998 		    encrypt_printsub(&pointer[1], length - 1, buf, sizeof(buf));
999 		    output_data("%s", buf);
1000 		}
1001 		break;
1002 
1003 	    case ENCRYPT_SUPPORT:
1004 		i = 2;
1005 		output_data(" SUPPORT ");
1006 		while (i < length) {
1007 		    if (ENCTYPE_NAME_OK(pointer[i]))
1008 			output_data("%s ", ENCTYPE_NAME(pointer[i]));
1009 		    else
1010 			output_data("%d ", pointer[i]);
1011 		    i++;
1012 		}
1013 		break;
1014 
1015 	    case ENCRYPT_ENC_KEYID:
1016 		output_data(" ENC_KEYID");
1017 		goto encommon;
1018 
1019 	    case ENCRYPT_DEC_KEYID:
1020 		output_data(" DEC_KEYID");
1021 		goto encommon;
1022 
1023 	    default:
1024 		output_data(" %d (unknown)", pointer[1]);
1025 	    encommon:
1026 		for (i = 2; i < length; i++) {
1027 		    output_data(" %d", pointer[i]);
1028 		}
1029 		break;
1030 	    }
1031 	    break;
1032 #endif	/* ENCRYPTION */
1033 
1034 	default:
1035 	    if (TELOPT_OK(pointer[0]))
1036 		output_data("%s (unknown)", TELOPT(pointer[0]));
1037 	    else
1038 		output_data("%d (unknown)", pointer[i]);
1039 	    for (i = 1; i < length; i++) {
1040 		output_data(" %d", pointer[i]);
1041 	    }
1042 	    break;
1043 	}
1044 	output_data("\r\n");
1045 }
1046 
1047 /*
1048  * Dump a data buffer in hex and ascii to the output data stream.
1049  */
1050 void
1051 printdata(const char *tag, char *ptr, int cnt)
1052 {
1053 	int i;
1054 	char xbuf[30];
1055 
1056 	while (cnt) {
1057 		/* flush net output buffer if no room for new data) */
1058 		if ((&netobuf[BUFSIZ] - nfrontp) < 80) {
1059 			netflush();
1060 		}
1061 
1062 		/* add a line of output */
1063 		output_data("%s: ", tag);
1064 		for (i = 0; i < 20 && cnt; i++) {
1065 			output_data("%02x", *ptr);
1066 			if (isprint(*ptr)) {
1067 				xbuf[i] = *ptr;
1068 			} else {
1069 				xbuf[i] = '.';
1070 			}
1071 			if (i % 2) {
1072 				output_data(" ");
1073 			}
1074 			cnt--;
1075 			ptr++;
1076 		}
1077 		xbuf[i] = '\0';
1078 		output_data(" %s\r\n", xbuf );
1079 	}
1080 }
1081 #endif /* DIAGNOSTICS */
1082