1 /*
2  * Copyright (c) 1988, 1990, 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 #include "telnet_locl.h"
35 
36 RCSID("$Id$");
37 
38 #if	defined(IPPROTO_IP) && defined(IP_TOS)
39 int tos = -1;
40 #endif	/* defined(IPPROTO_IP) && defined(IP_TOS) */
41 
42 char	*hostname;
43 static char _hostname[MaxHostNameLen];
44 
45 typedef int (*intrtn_t)(int, char**);
46 static int call(intrtn_t, ...);
47 
48 typedef struct {
49 	char	*name;		/* command name */
50 	char	*help;		/* help string (NULL for no help) */
51 	int	(*handler)();	/* routine which executes command */
52 	int	needconnect;	/* Do we need to be connected to execute? */
53 } Command;
54 
55 static char line[256];
56 static char saveline[256];
57 static int margc;
58 static char *margv[20];
59 
60 static void
61 makeargv()
62 {
63     char *cp, *cp2, c;
64     char **argp = margv;
65 
66     margc = 0;
67     cp = line;
68     if (*cp == '!') {		/* Special case shell escape */
69 	/* save for shell command */
70 	strlcpy(saveline, line, sizeof(saveline));
71 	*argp++ = "!";		/* No room in string to get this */
72 	margc++;
73 	cp++;
74     }
75     while ((c = *cp)) {
76 	int inquote = 0;
77 	while (isspace((unsigned char)c))
78 	    c = *++cp;
79 	if (c == '\0')
80 	    break;
81 	*argp++ = cp;
82 	margc += 1;
83 	for (cp2 = cp; c != '\0'; c = *++cp) {
84 	    if (inquote) {
85 		if (c == inquote) {
86 		    inquote = 0;
87 		    continue;
88 		}
89 	    } else {
90 		if (c == '\\') {
91 		    if ((c = *++cp) == '\0')
92 			break;
93 		} else if (c == '"') {
94 		    inquote = '"';
95 		    continue;
96 		} else if (c == '\'') {
97 		    inquote = '\'';
98 		    continue;
99 		} else if (isspace((unsigned char)c))
100 		    break;
101 	    }
102 	    *cp2++ = c;
103 	}
104 	*cp2 = '\0';
105 	if (c == '\0')
106 	    break;
107 	cp++;
108     }
109     *argp++ = 0;
110 }
111 
112 /*
113  * Make a character string into a number.
114  *
115  * Todo:  1.  Could take random integers (12, 0x12, 012, 0b1).
116  */
117 
118 static char
119 special(char *s)
120 {
121 	char c;
122 	char b;
123 
124 	switch (*s) {
125 	case '^':
126 		b = *++s;
127 		if (b == '?') {
128 		    c = b | 0x40;		/* DEL */
129 		} else {
130 		    c = b & 0x1f;
131 		}
132 		break;
133 	default:
134 		c = *s;
135 		break;
136 	}
137 	return c;
138 }
139 
140 /*
141  * Construct a control character sequence
142  * for a special character.
143  */
144 static char *
145 control(cc_t c)
146 {
147 	static char buf[5];
148 	/*
149 	 * The only way I could get the Sun 3.5 compiler
150 	 * to shut up about
151 	 *	if ((unsigned int)c >= 0x80)
152 	 * was to assign "c" to an unsigned int variable...
153 	 * Arggg....
154 	 */
155 	unsigned int uic = (unsigned int)c;
156 
157 	if (uic == 0x7f)
158 		return ("^?");
159 	if (c == (cc_t)_POSIX_VDISABLE) {
160 		return "off";
161 	}
162 	if (uic >= 0x80) {
163 		buf[0] = '\\';
164 		buf[1] = ((c>>6)&07) + '0';
165 		buf[2] = ((c>>3)&07) + '0';
166 		buf[3] = (c&07) + '0';
167 		buf[4] = 0;
168 	} else if (uic >= 0x20) {
169 		buf[0] = c;
170 		buf[1] = 0;
171 	} else {
172 		buf[0] = '^';
173 		buf[1] = '@'+c;
174 		buf[2] = 0;
175 	}
176 	return (buf);
177 }
178 
179 
180 
181 /*
182  *	The following are data structures and routines for
183  *	the "send" command.
184  *
185  */
186 
187 struct sendlist {
188     char	*name;		/* How user refers to it (case independent) */
189     char	*help;		/* Help information (0 ==> no help) */
190     int		needconnect;	/* Need to be connected */
191     int		narg;		/* Number of arguments */
192     int		(*handler)();	/* Routine to perform (for special ops) */
193     int		nbyte;		/* Number of bytes to send this command */
194     int		what;		/* Character to be sent (<0 ==> special) */
195 };
196 
197 
198 static int
199 	send_esc (void),
200 	send_help (void),
201 	send_docmd (char *),
202 	send_dontcmd (char *),
203 	send_willcmd (char *),
204 	send_wontcmd (char *);
205 
206 static struct sendlist Sendlist[] = {
207     { "ao",	"Send Telnet Abort output",		1, 0, 0, 2, AO },
208     { "ayt",	"Send Telnet 'Are You There'",		1, 0, 0, 2, AYT },
209     { "brk",	"Send Telnet Break",			1, 0, 0, 2, BREAK },
210     { "break",	0,					1, 0, 0, 2, BREAK },
211     { "ec",	"Send Telnet Erase Character",		1, 0, 0, 2, EC },
212     { "el",	"Send Telnet Erase Line",		1, 0, 0, 2, EL },
213     { "escape",	"Send current escape character",	1, 0, send_esc, 1, 0 },
214     { "ga",	"Send Telnet 'Go Ahead' sequence",	1, 0, 0, 2, GA },
215     { "ip",	"Send Telnet Interrupt Process",	1, 0, 0, 2, IP },
216     { "intp",	0,					1, 0, 0, 2, IP },
217     { "interrupt", 0,					1, 0, 0, 2, IP },
218     { "intr",	0,					1, 0, 0, 2, IP },
219     { "nop",	"Send Telnet 'No operation'",		1, 0, 0, 2, NOP },
220     { "eor",	"Send Telnet 'End of Record'",		1, 0, 0, 2, EOR },
221     { "abort",	"Send Telnet 'Abort Process'",		1, 0, 0, 2, ABORT },
222     { "susp",	"Send Telnet 'Suspend Process'",	1, 0, 0, 2, SUSP },
223     { "eof",	"Send Telnet End of File Character",	1, 0, 0, 2, xEOF },
224     { "synch",	"Perform Telnet 'Synch operation'",	1, 0, dosynch, 2, 0 },
225     { "getstatus", "Send request for STATUS",		1, 0, get_status, 6, 0 },
226     { "?",	"Display send options",			0, 0, send_help, 0, 0 },
227     { "help",	0,					0, 0, send_help, 0, 0 },
228     { "do",	0,					0, 1, send_docmd, 3, 0 },
229     { "dont",	0,					0, 1, send_dontcmd, 3, 0 },
230     { "will",	0,					0, 1, send_willcmd, 3, 0 },
231     { "wont",	0,					0, 1, send_wontcmd, 3, 0 },
232     { 0 }
233 };
234 
235 #define	GETSEND(name) ((struct sendlist *) genget(name, (char **) Sendlist, \
236 				sizeof(struct sendlist)))
237 
238 static int
239 sendcmd(int argc, char **argv)
240 {
241     int count;		/* how many bytes we are going to need to send */
242     int i;
243     struct sendlist *s;	/* pointer to current command */
244     int success = 0;
245     int needconnect = 0;
246 
247     if (argc < 2) {
248 	printf("need at least one argument for 'send' command\r\n");
249 	printf("'send ?' for help\r\n");
250 	return 0;
251     }
252     /*
253      * First, validate all the send arguments.
254      * In addition, we see how much space we are going to need, and
255      * whether or not we will be doing a "SYNCH" operation (which
256      * flushes the network queue).
257      */
258     count = 0;
259     for (i = 1; i < argc; i++) {
260 	s = GETSEND(argv[i]);
261 	if (s == 0) {
262 	    printf("Unknown send argument '%s'\r\n'send ?' for help.\r\n",
263 			argv[i]);
264 	    return 0;
265 	} else if (Ambiguous(s)) {
266 	    printf("Ambiguous send argument '%s'\r\n'send ?' for help.\r\n",
267 			argv[i]);
268 	    return 0;
269 	}
270 	if (i + s->narg >= argc) {
271 	    fprintf(stderr,
272 	    "Need %d argument%s to 'send %s' command.  'send %s ?' for help.\r\n",
273 		s->narg, s->narg == 1 ? "" : "s", s->name, s->name);
274 	    return 0;
275 	}
276 	count += s->nbyte;
277 	if (s->handler == send_help) {
278 	    send_help();
279 	    return 0;
280 	}
281 
282 	i += s->narg;
283 	needconnect += s->needconnect;
284     }
285     if (!connected && needconnect) {
286 	printf("?Need to be connected first.\r\n");
287 	printf("'send ?' for help\r\n");
288 	return 0;
289     }
290     /* Now, do we have enough room? */
291     if (NETROOM() < count) {
292 	printf("There is not enough room in the buffer TO the network\r\n");
293 	printf("to process your request.  Nothing will be done.\r\n");
294 	printf("('send synch' will throw away most data in the network\r\n");
295 	printf("buffer, if this might help.)\r\n");
296 	return 0;
297     }
298     /* OK, they are all OK, now go through again and actually send */
299     count = 0;
300     for (i = 1; i < argc; i++) {
301 	if ((s = GETSEND(argv[i])) == 0) {
302 	    fprintf(stderr, "Telnet 'send' error - argument disappeared!\r\n");
303 	    quit();
304 	    /*NOTREACHED*/
305 	}
306 	if (s->handler) {
307 	    count++;
308 	    success += (*s->handler)((s->narg > 0) ? argv[i+1] : 0,
309 				  (s->narg > 1) ? argv[i+2] : 0);
310 	    i += s->narg;
311 	} else {
312 	    NET2ADD(IAC, s->what);
313 	    printoption("SENT", IAC, s->what);
314 	}
315     }
316     return (count == success);
317 }
318 
319 static int
320 send_tncmd(void (*func)(), char *cmd, char *name);
321 
322 static int
323 send_esc()
324 {
325     NETADD(escape);
326     return 1;
327 }
328 
329 static int
330 send_docmd(char *name)
331 {
332     return(send_tncmd(send_do, "do", name));
333 }
334 
335 static int
336 send_dontcmd(char *name)
337 {
338     return(send_tncmd(send_dont, "dont", name));
339 }
340 
341 static int
342 send_willcmd(char *name)
343 {
344     return(send_tncmd(send_will, "will", name));
345 }
346 
347 static int
348 send_wontcmd(char *name)
349 {
350     return(send_tncmd(send_wont, "wont", name));
351 }
352 
353 extern char *telopts[];		/* XXX */
354 
355 static int
356 send_tncmd(void (*func)(), char *cmd, char *name)
357 {
358     char **cpp;
359     int val = 0;
360 
361     if (isprefix(name, "help") || isprefix(name, "?")) {
362 	int col, len;
363 
364 	printf("Usage: send %s <value|option>\r\n", cmd);
365 	printf("\"value\" must be from 0 to 255\r\n");
366 	printf("Valid options are:\r\n\t");
367 
368 	col = 8;
369 	for (cpp = telopts; *cpp; cpp++) {
370 	    len = strlen(*cpp) + 3;
371 	    if (col + len > 65) {
372 		printf("\r\n\t");
373 		col = 8;
374 	    }
375 	    printf(" \"%s\"", *cpp);
376 	    col += len;
377 	}
378 	printf("\r\n");
379 	return 0;
380     }
381     cpp = genget(name, telopts, sizeof(char *));
382     if (Ambiguous(cpp)) {
383 	fprintf(stderr,"'%s': ambiguous argument ('send %s ?' for help).\r\n",
384 					name, cmd);
385 	return 0;
386     }
387     if (cpp) {
388 	val = cpp - telopts;
389     } else {
390 	char *cp = name;
391 
392 	while (*cp >= '0' && *cp <= '9') {
393 	    val *= 10;
394 	    val += *cp - '0';
395 	    cp++;
396 	}
397 	if (*cp != 0) {
398 	    fprintf(stderr, "'%s': unknown argument ('send %s ?' for help).\r\n",
399 					name, cmd);
400 	    return 0;
401 	} else if (val < 0 || val > 255) {
402 	    fprintf(stderr, "'%s': bad value ('send %s ?' for help).\r\n",
403 					name, cmd);
404 	    return 0;
405 	}
406     }
407     if (!connected) {
408 	printf("?Need to be connected first.\r\n");
409 	return 0;
410     }
411     (*func)(val, 1);
412     return 1;
413 }
414 
415 static int
416 send_help()
417 {
418     struct sendlist *s;	/* pointer to current command */
419     for (s = Sendlist; s->name; s++) {
420 	if (s->help)
421 	    printf("%-15s %s\r\n", s->name, s->help);
422     }
423     return(0);
424 }
425 
426 /*
427  * The following are the routines and data structures referred
428  * to by the arguments to the "toggle" command.
429  */
430 
431 static int
432 lclchars()
433 {
434     donelclchars = 1;
435     return 1;
436 }
437 
438 static int
439 togdebug()
440 {
441 #ifndef	NOT43
442     if (net > 0 &&
443 	(SetSockOpt(net, SOL_SOCKET, SO_DEBUG, debug)) < 0) {
444 	    perror("setsockopt (SO_DEBUG)");
445     }
446 #else	/* NOT43 */
447     if (debug) {
448 	if (net > 0 && SetSockOpt(net, SOL_SOCKET, SO_DEBUG, 0, 0) < 0)
449 	    perror("setsockopt (SO_DEBUG)");
450     } else
451 	printf("Cannot turn off socket debugging\r\n");
452 #endif	/* NOT43 */
453     return 1;
454 }
455 
456 static int
457 togcrlf()
458 {
459     if (crlf) {
460 	printf("Will send carriage returns as telnet <CR><LF>.\r\n");
461     } else {
462 	printf("Will send carriage returns as telnet <CR><NUL>.\r\n");
463     }
464     return 1;
465 }
466 
467 int binmode;
468 
469 static int
470 togbinary(int val)
471 {
472     donebinarytoggle = 1;
473 
474     if (val >= 0) {
475 	binmode = val;
476     } else {
477 	if (my_want_state_is_will(TELOPT_BINARY) &&
478 				my_want_state_is_do(TELOPT_BINARY)) {
479 	    binmode = 1;
480 	} else if (my_want_state_is_wont(TELOPT_BINARY) &&
481 				my_want_state_is_dont(TELOPT_BINARY)) {
482 	    binmode = 0;
483 	}
484 	val = binmode ? 0 : 1;
485     }
486 
487     if (val == 1) {
488 	if (my_want_state_is_will(TELOPT_BINARY) &&
489 					my_want_state_is_do(TELOPT_BINARY)) {
490 	    printf("Already operating in binary mode with remote host.\r\n");
491 	} else {
492 	    printf("Negotiating binary mode with remote host.\r\n");
493 	    tel_enter_binary(3);
494 	}
495     } else {
496 	if (my_want_state_is_wont(TELOPT_BINARY) &&
497 					my_want_state_is_dont(TELOPT_BINARY)) {
498 	    printf("Already in network ascii mode with remote host.\r\n");
499 	} else {
500 	    printf("Negotiating network ascii mode with remote host.\r\n");
501 	    tel_leave_binary(3);
502 	}
503     }
504     return 1;
505 }
506 
507 static int
508 togrbinary(int val)
509 {
510     donebinarytoggle = 1;
511 
512     if (val == -1)
513 	val = my_want_state_is_do(TELOPT_BINARY) ? 0 : 1;
514 
515     if (val == 1) {
516 	if (my_want_state_is_do(TELOPT_BINARY)) {
517 	    printf("Already receiving in binary mode.\r\n");
518 	} else {
519 	    printf("Negotiating binary mode on input.\r\n");
520 	    tel_enter_binary(1);
521 	}
522     } else {
523 	if (my_want_state_is_dont(TELOPT_BINARY)) {
524 	    printf("Already receiving in network ascii mode.\r\n");
525 	} else {
526 	    printf("Negotiating network ascii mode on input.\r\n");
527 	    tel_leave_binary(1);
528 	}
529     }
530     return 1;
531 }
532 
533 static int
534 togxbinary(int val)
535 {
536     donebinarytoggle = 1;
537 
538     if (val == -1)
539 	val = my_want_state_is_will(TELOPT_BINARY) ? 0 : 1;
540 
541     if (val == 1) {
542 	if (my_want_state_is_will(TELOPT_BINARY)) {
543 	    printf("Already transmitting in binary mode.\r\n");
544 	} else {
545 	    printf("Negotiating binary mode on output.\r\n");
546 	    tel_enter_binary(2);
547 	}
548     } else {
549 	if (my_want_state_is_wont(TELOPT_BINARY)) {
550 	    printf("Already transmitting in network ascii mode.\r\n");
551 	} else {
552 	    printf("Negotiating network ascii mode on output.\r\n");
553 	    tel_leave_binary(2);
554 	}
555     }
556     return 1;
557 }
558 
559 
560 static int togglehelp (void);
561 #if	defined(AUTHENTICATION)
562 extern int auth_togdebug (int);
563 #endif
564 #if	defined(ENCRYPTION)
565 extern int EncryptAutoEnc (int);
566 extern int EncryptAutoDec (int);
567 extern int EncryptDebug (int);
568 extern int EncryptVerbose (int);
569 #endif
570 
571 struct togglelist {
572     char	*name;		/* name of toggle */
573     char	*help;		/* help message */
574     int		(*handler)();	/* routine to do actual setting */
575     int		*variable;
576     char	*actionexplanation;
577 };
578 
579 static struct togglelist Togglelist[] = {
580     { "autoflush",
581 	"flushing of output when sending interrupt characters",
582 	    0,
583 		&autoflush,
584 		    "flush output when sending interrupt characters" },
585     { "autosynch",
586 	"automatic sending of interrupt characters in urgent mode",
587 	    0,
588 		&autosynch,
589 		    "send interrupt characters in urgent mode" },
590 #if	defined(AUTHENTICATION)
591     { "autologin",
592 	"automatic sending of login and/or authentication info",
593 	    0,
594 		&autologin,
595 		    "send login name and/or authentication information" },
596     { "authdebug",
597 	"authentication debugging",
598 	    auth_togdebug,
599 		0,
600 		     "print authentication debugging information" },
601 #endif
602 #if	defined(ENCRYPTION)
603     { "autoencrypt",
604 	"automatic encryption of data stream",
605 	    EncryptAutoEnc,
606 		0,
607 		    "automatically encrypt output" },
608     { "autodecrypt",
609 	"automatic decryption of data stream",
610 	    EncryptAutoDec,
611 		0,
612 		    "automatically decrypt input" },
613     { "verbose_encrypt",
614 	"verbose encryption output",
615 	    EncryptVerbose,
616 		0,
617 		    "print verbose encryption output" },
618     { "encdebug",
619 	"encryption debugging",
620 	    EncryptDebug,
621 		0,
622 		    "print encryption debugging information" },
623 #endif
624 #if defined(KRB5)
625     { "forward",
626 	"credentials forwarding",
627 	    kerberos5_set_forward,
628 		0,
629 		    "forward credentials" },
630     { "forwardable",
631 	"forwardable flag of forwarded credentials",
632 	    kerberos5_set_forwardable,
633 		0,
634 		    "forward forwardable credentials" },
635 #endif
636    { "skiprc",
637 	"don't read ~/.telnetrc file",
638 	    0,
639 		&skiprc,
640 		    "skip reading of ~/.telnetrc file" },
641     { "binary",
642 	"sending and receiving of binary data",
643 	    togbinary,
644 		0,
645 		    0 },
646     { "inbinary",
647 	"receiving of binary data",
648 	    togrbinary,
649 		0,
650 		    0 },
651     { "outbinary",
652 	"sending of binary data",
653 	    togxbinary,
654 		0,
655 		    0 },
656     { "crlf",
657 	"sending carriage returns as telnet <CR><LF>",
658 	    togcrlf,
659 		&crlf,
660 		    0 },
661     { "crmod",
662 	"mapping of received carriage returns",
663 	    0,
664 		&crmod,
665 		    "map carriage return on output" },
666     { "localchars",
667 	"local recognition of certain control characters",
668 	    lclchars,
669 		&localchars,
670 		    "recognize certain control characters" },
671     { " ", "", 0 },		/* empty line */
672     { "debug",
673 	"debugging",
674 	    togdebug,
675 		&debug,
676 		    "turn on socket level debugging" },
677     { "netdata",
678 	"printing of hexadecimal network data (debugging)",
679 	    0,
680 		&netdata,
681 		    "print hexadecimal representation of network traffic" },
682     { "prettydump",
683 	"output of \"netdata\" to user readable format (debugging)",
684 	    0,
685 		&prettydump,
686 		    "print user readable output for \"netdata\"" },
687     { "options",
688 	"viewing of options processing (debugging)",
689 	    0,
690 		&showoptions,
691 		    "show option processing" },
692     { "termdata",
693 	"printing of hexadecimal terminal data (debugging)",
694 	    0,
695 		&termdata,
696 		    "print hexadecimal representation of terminal traffic" },
697     { "?",
698 	0,
699 	    togglehelp },
700     { "help",
701 	0,
702 	    togglehelp },
703     { 0 }
704 };
705 
706 static int
707 togglehelp()
708 {
709     struct togglelist *c;
710 
711     for (c = Togglelist; c->name; c++) {
712 	if (c->help) {
713 	    if (*c->help)
714 		printf("%-15s toggle %s\r\n", c->name, c->help);
715 	    else
716 		printf("\r\n");
717 	}
718     }
719     printf("\r\n");
720     printf("%-15s %s\r\n", "?", "display help information");
721     return 0;
722 }
723 
724 static void
725 settogglehelp(int set)
726 {
727     struct togglelist *c;
728 
729     for (c = Togglelist; c->name; c++) {
730 	if (c->help) {
731 	    if (*c->help)
732 		printf("%-15s %s %s\r\n", c->name, set ? "enable" : "disable",
733 						c->help);
734 	    else
735 		printf("\r\n");
736 	}
737     }
738 }
739 
740 #define	GETTOGGLE(name) (struct togglelist *) \
741 		genget(name, (char **) Togglelist, sizeof(struct togglelist))
742 
743 static int
744 toggle(int argc, char *argv[])
745 {
746     int retval = 1;
747     char *name;
748     struct togglelist *c;
749 
750     if (argc < 2) {
751 	fprintf(stderr,
752 	    "Need an argument to 'toggle' command.  'toggle ?' for help.\r\n");
753 	return 0;
754     }
755     argc--;
756     argv++;
757     while (argc--) {
758 	name = *argv++;
759 	c = GETTOGGLE(name);
760 	if (Ambiguous(c)) {
761 	    fprintf(stderr, "'%s': ambiguous argument ('toggle ?' for help).\r\n",
762 					name);
763 	    return 0;
764 	} else if (c == 0) {
765 	    fprintf(stderr, "'%s': unknown argument ('toggle ?' for help).\r\n",
766 					name);
767 	    return 0;
768 	} else {
769 	    if (c->variable) {
770 		*c->variable = !*c->variable;		/* invert it */
771 		if (c->actionexplanation) {
772 		    printf("%s %s.\r\n", *c->variable? "Will" : "Won't",
773 							c->actionexplanation);
774 		}
775 	    }
776 	    if (c->handler) {
777 		retval &= (*c->handler)(-1);
778 	    }
779 	}
780     }
781     return retval;
782 }
783 
784 /*
785  * The following perform the "set" command.
786  */
787 
788 struct termios new_tc = { 0 };
789 
790 struct setlist {
791     char *name;				/* name */
792     char *help;				/* help information */
793     void (*handler)();
794     cc_t *charp;			/* where it is located at */
795 };
796 
797 static struct setlist Setlist[] = {
798 #ifdef	KLUDGELINEMODE
799     { "echo", 	"character to toggle local echoing on/off", 0, &echoc },
800 #endif
801     { "escape",	"character to escape back to telnet command mode", 0, &escape },
802     { "rlogin", "rlogin escape character", 0, &rlogin },
803     { "tracefile", "file to write trace information to", SetNetTrace, (cc_t *)NetTraceFile},
804     { " ", "" },
805     { " ", "The following need 'localchars' to be toggled true", 0, 0 },
806     { "flushoutput", "character to cause an Abort Output", 0, &termFlushChar },
807     { "interrupt", "character to cause an Interrupt Process", 0, &termIntChar },
808     { "quit",	"character to cause an Abort process", 0, &termQuitChar },
809     { "eof",	"character to cause an EOF ", 0, &termEofChar },
810     { " ", "" },
811     { " ", "The following are for local editing in linemode", 0, 0 },
812     { "erase",	"character to use to erase a character", 0, &termEraseChar },
813     { "kill",	"character to use to erase a line", 0, &termKillChar },
814     { "lnext",	"character to use for literal next", 0, &termLiteralNextChar },
815     { "susp",	"character to cause a Suspend Process", 0, &termSuspChar },
816     { "reprint", "character to use for line reprint", 0, &termRprntChar },
817     { "worderase", "character to use to erase a word", 0, &termWerasChar },
818     { "start",	"character to use for XON", 0, &termStartChar },
819     { "stop",	"character to use for XOFF", 0, &termStopChar },
820     { "forw1",	"alternate end of line character", 0, &termForw1Char },
821     { "forw2",	"alternate end of line character", 0, &termForw2Char },
822     { "ayt",	"alternate AYT character", 0, &termAytChar },
823     { 0 }
824 };
825 
826 static struct setlist *
827 getset(char *name)
828 {
829     return (struct setlist *)
830 		genget(name, (char **) Setlist, sizeof(struct setlist));
831 }
832 
833 void
834 set_escape_char(char *s)
835 {
836 	if (rlogin != _POSIX_VDISABLE) {
837 		rlogin = (s && *s) ? special(s) : _POSIX_VDISABLE;
838 		printf("Telnet rlogin escape character is '%s'.\r\n",
839 					control(rlogin));
840 	} else {
841 		escape = (s && *s) ? special(s) : _POSIX_VDISABLE;
842 		printf("Telnet escape character is '%s'.\r\n", control(escape));
843 	}
844 }
845 
846 static int
847 setcmd(int argc, char *argv[])
848 {
849     int value;
850     struct setlist *ct;
851     struct togglelist *c;
852 
853     if (argc < 2 || argc > 3) {
854 	printf("Format is 'set Name Value'\r\n'set ?' for help.\r\n");
855 	return 0;
856     }
857     if ((argc == 2) && (isprefix(argv[1], "?") || isprefix(argv[1], "help"))) {
858 	for (ct = Setlist; ct->name; ct++)
859 	    printf("%-15s %s\r\n", ct->name, ct->help);
860 	printf("\r\n");
861 	settogglehelp(1);
862 	printf("%-15s %s\r\n", "?", "display help information");
863 	return 0;
864     }
865 
866     ct = getset(argv[1]);
867     if (ct == 0) {
868 	c = GETTOGGLE(argv[1]);
869 	if (c == 0) {
870 	    fprintf(stderr, "'%s': unknown argument ('set ?' for help).\r\n",
871 			argv[1]);
872 	    return 0;
873 	} else if (Ambiguous(c)) {
874 	    fprintf(stderr, "'%s': ambiguous argument ('set ?' for help).\r\n",
875 			argv[1]);
876 	    return 0;
877 	}
878 	if (c->variable) {
879 	    if ((argc == 2) || (strcmp("on", argv[2]) == 0))
880 		*c->variable = 1;
881 	    else if (strcmp("off", argv[2]) == 0)
882 		*c->variable = 0;
883 	    else {
884 		printf("Format is 'set togglename [on|off]'\r\n'set ?' for help.\r\n");
885 		return 0;
886 	    }
887 	    if (c->actionexplanation) {
888 		printf("%s %s.\r\n", *c->variable? "Will" : "Won't",
889 							c->actionexplanation);
890 	    }
891 	}
892 	if (c->handler)
893 	    (*c->handler)(1);
894     } else if (argc != 3) {
895 	printf("Format is 'set Name Value'\r\n'set ?' for help.\r\n");
896 	return 0;
897     } else if (Ambiguous(ct)) {
898 	fprintf(stderr, "'%s': ambiguous argument ('set ?' for help).\r\n",
899 			argv[1]);
900 	return 0;
901     } else if (ct->handler) {
902 	(*ct->handler)(argv[2]);
903 	printf("%s set to \"%s\".\r\n", ct->name, (char *)ct->charp);
904     } else {
905 	if (strcmp("off", argv[2])) {
906 	    value = special(argv[2]);
907 	} else {
908 	    value = _POSIX_VDISABLE;
909 	}
910 	*(ct->charp) = (cc_t)value;
911 	printf("%s character is '%s'.\r\n", ct->name, control(*(ct->charp)));
912     }
913     slc_check();
914     return 1;
915 }
916 
917 static int
918 unsetcmd(int argc, char *argv[])
919 {
920     struct setlist *ct;
921     struct togglelist *c;
922     char *name;
923 
924     if (argc < 2) {
925 	fprintf(stderr,
926 	    "Need an argument to 'unset' command.  'unset ?' for help.\r\n");
927 	return 0;
928     }
929     if (isprefix(argv[1], "?") || isprefix(argv[1], "help")) {
930 	for (ct = Setlist; ct->name; ct++)
931 	    printf("%-15s %s\r\n", ct->name, ct->help);
932 	printf("\r\n");
933 	settogglehelp(0);
934 	printf("%-15s %s\r\n", "?", "display help information");
935 	return 0;
936     }
937 
938     argc--;
939     argv++;
940     while (argc--) {
941 	name = *argv++;
942 	ct = getset(name);
943 	if (ct == 0) {
944 	    c = GETTOGGLE(name);
945 	    if (c == 0) {
946 		fprintf(stderr, "'%s': unknown argument ('unset ?' for help).\r\n",
947 			name);
948 		return 0;
949 	    } else if (Ambiguous(c)) {
950 		fprintf(stderr, "'%s': ambiguous argument ('unset ?' for help).\r\n",
951 			name);
952 		return 0;
953 	    }
954 	    if (c->variable) {
955 		*c->variable = 0;
956 		if (c->actionexplanation) {
957 		    printf("%s %s.\r\n", *c->variable? "Will" : "Won't",
958 							c->actionexplanation);
959 		}
960 	    }
961 	    if (c->handler)
962 		(*c->handler)(0);
963 	} else if (Ambiguous(ct)) {
964 	    fprintf(stderr, "'%s': ambiguous argument ('unset ?' for help).\r\n",
965 			name);
966 	    return 0;
967 	} else if (ct->handler) {
968 	    (*ct->handler)(0);
969 	    printf("%s reset to \"%s\".\r\n", ct->name, (char *)ct->charp);
970 	} else {
971 	    *(ct->charp) = _POSIX_VDISABLE;
972 	    printf("%s character is '%s'.\r\n", ct->name, control(*(ct->charp)));
973 	}
974     }
975     return 1;
976 }
977 
978 /*
979  * The following are the data structures and routines for the
980  * 'mode' command.
981  */
982 #ifdef	KLUDGELINEMODE
983 
984 static int
985 dokludgemode(void)
986 {
987     kludgelinemode = 1;
988     send_wont(TELOPT_LINEMODE, 1);
989     send_dont(TELOPT_SGA, 1);
990     send_dont(TELOPT_ECHO, 1);
991     return 1;
992 }
993 #endif
994 
995 static int
996 dolinemode()
997 {
998 #ifdef	KLUDGELINEMODE
999     if (kludgelinemode)
1000 	send_dont(TELOPT_SGA, 1);
1001 #endif
1002     send_will(TELOPT_LINEMODE, 1);
1003     send_dont(TELOPT_ECHO, 1);
1004     return 1;
1005 }
1006 
1007 static int
1008 docharmode()
1009 {
1010 #ifdef	KLUDGELINEMODE
1011     if (kludgelinemode)
1012 	send_do(TELOPT_SGA, 1);
1013     else
1014 #endif
1015     send_wont(TELOPT_LINEMODE, 1);
1016     send_do(TELOPT_ECHO, 1);
1017     return 1;
1018 }
1019 
1020 static int
1021 dolmmode(int bit, int on)
1022 {
1023     unsigned char c;
1024 
1025     if (my_want_state_is_wont(TELOPT_LINEMODE)) {
1026 	printf("?Need to have LINEMODE option enabled first.\r\n");
1027 	printf("'mode ?' for help.\r\n");
1028  	return 0;
1029     }
1030 
1031     if (on)
1032 	c = (linemode | bit);
1033     else
1034 	c = (linemode & ~bit);
1035     lm_mode(&c, 1, 1);
1036     return 1;
1037 }
1038 
1039 static int
1040 tn_setmode(int bit)
1041 {
1042     return dolmmode(bit, 1);
1043 }
1044 
1045 static int
1046 tn_clearmode(int bit)
1047 {
1048     return dolmmode(bit, 0);
1049 }
1050 
1051 struct modelist {
1052 	char	*name;		/* command name */
1053 	char	*help;		/* help string */
1054 	int	(*handler)();	/* routine which executes command */
1055 	int	needconnect;	/* Do we need to be connected to execute? */
1056 	int	arg1;
1057 };
1058 
1059 static int modehelp(void);
1060 
1061 static struct modelist ModeList[] = {
1062     { "character", "Disable LINEMODE option",	docharmode, 1 },
1063 #ifdef	KLUDGELINEMODE
1064     { "",	"(or disable obsolete line-by-line mode)", 0 },
1065 #endif
1066     { "line",	"Enable LINEMODE option",	dolinemode, 1 },
1067 #ifdef	KLUDGELINEMODE
1068     { "",	"(or enable obsolete line-by-line mode)", 0 },
1069 #endif
1070     { "", "", 0 },
1071     { "",	"These require the LINEMODE option to be enabled", 0 },
1072     { "isig",	"Enable signal trapping",	tn_setmode, 1, MODE_TRAPSIG },
1073     { "+isig",	0,				tn_setmode, 1, MODE_TRAPSIG },
1074     { "-isig",	"Disable signal trapping",	tn_clearmode, 1, MODE_TRAPSIG },
1075     { "edit",	"Enable character editing",	tn_setmode, 1, MODE_EDIT },
1076     { "+edit",	0,				tn_setmode, 1, MODE_EDIT },
1077     { "-edit",	"Disable character editing",	tn_clearmode, 1, MODE_EDIT },
1078     { "softtabs", "Enable tab expansion",	tn_setmode, 1, MODE_SOFT_TAB },
1079     { "+softtabs", 0,				tn_setmode, 1, MODE_SOFT_TAB },
1080     { "-softtabs", "Disable tab expansion",	tn_clearmode, 1, MODE_SOFT_TAB },
1081     { "litecho", "Enable literal character echo", tn_setmode, 1, MODE_LIT_ECHO },
1082     { "+litecho", 0,				tn_setmode, 1, MODE_LIT_ECHO },
1083     { "-litecho", "Disable literal character echo", tn_clearmode, 1, MODE_LIT_ECHO },
1084     { "help",	0,				modehelp, 0 },
1085 #ifdef	KLUDGELINEMODE
1086     { "kludgeline", 0,				dokludgemode, 1 },
1087 #endif
1088     { "", "", 0 },
1089     { "?",	"Print help information",	modehelp, 0 },
1090     { 0 },
1091 };
1092 
1093 
1094 static int
1095 modehelp(void)
1096 {
1097     struct modelist *mt;
1098 
1099     printf("format is:  'mode Mode', where 'Mode' is one of:\r\n\r\n");
1100     for (mt = ModeList; mt->name; mt++) {
1101 	if (mt->help) {
1102 	    if (*mt->help)
1103 		printf("%-15s %s\r\n", mt->name, mt->help);
1104 	    else
1105 		printf("\r\n");
1106 	}
1107     }
1108     return 0;
1109 }
1110 
1111 #define	GETMODECMD(name) (struct modelist *) \
1112 		genget(name, (char **) ModeList, sizeof(struct modelist))
1113 
1114 static int
1115 modecmd(int argc, char **argv)
1116 {
1117     struct modelist *mt;
1118 
1119     if (argc != 2) {
1120 	printf("'mode' command requires an argument\r\n");
1121 	printf("'mode ?' for help.\r\n");
1122     } else if ((mt = GETMODECMD(argv[1])) == 0) {
1123 	fprintf(stderr, "Unknown mode '%s' ('mode ?' for help).\r\n", argv[1]);
1124     } else if (Ambiguous(mt)) {
1125 	fprintf(stderr, "Ambiguous mode '%s' ('mode ?' for help).\r\n", argv[1]);
1126     } else if (mt->needconnect && !connected) {
1127 	printf("?Need to be connected first.\r\n");
1128 	printf("'mode ?' for help.\r\n");
1129     } else if (mt->handler) {
1130 	return (*mt->handler)(mt->arg1);
1131     }
1132     return 0;
1133 }
1134 
1135 /*
1136  * The following data structures and routines implement the
1137  * "display" command.
1138  */
1139 
1140 static int
1141 display(int argc, char *argv[])
1142 {
1143     struct togglelist *tl;
1144     struct setlist *sl;
1145 
1146 #define	dotog(tl)	if (tl->variable && tl->actionexplanation) { \
1147 			    if (*tl->variable) { \
1148 				printf("will"); \
1149 			    } else { \
1150 				printf("won't"); \
1151 			    } \
1152 			    printf(" %s.\r\n", tl->actionexplanation); \
1153 			}
1154 
1155 #define	doset(sl)   if (sl->name && *sl->name != ' ') { \
1156 			if (sl->handler == 0) \
1157 			    printf("%-15s [%s]\r\n", sl->name, control(*sl->charp)); \
1158 			else \
1159 			    printf("%-15s \"%s\"\r\n", sl->name, (char *)sl->charp); \
1160 		    }
1161 
1162     if (argc == 1) {
1163 	for (tl = Togglelist; tl->name; tl++) {
1164 	    dotog(tl);
1165 	}
1166 	printf("\r\n");
1167 	for (sl = Setlist; sl->name; sl++) {
1168 	    doset(sl);
1169 	}
1170     } else {
1171 	int i;
1172 
1173 	for (i = 1; i < argc; i++) {
1174 	    sl = getset(argv[i]);
1175 	    tl = GETTOGGLE(argv[i]);
1176 	    if (Ambiguous(sl) || Ambiguous(tl)) {
1177 		printf("?Ambiguous argument '%s'.\r\n", argv[i]);
1178 		return 0;
1179 	    } else if (!sl && !tl) {
1180 		printf("?Unknown argument '%s'.\r\n", argv[i]);
1181 		return 0;
1182 	    } else {
1183 		if (tl) {
1184 		    dotog(tl);
1185 		}
1186 		if (sl) {
1187 		    doset(sl);
1188 		}
1189 	    }
1190 	}
1191     }
1192 /*@*/optionstatus();
1193 #if	defined(ENCRYPTION)
1194     EncryptStatus();
1195 #endif
1196     return 1;
1197 #undef	doset
1198 #undef	dotog
1199 }
1200 
1201 /*
1202  * The following are the data structures, and many of the routines,
1203  * relating to command processing.
1204  */
1205 
1206 /*
1207  * Set the escape character.
1208  */
1209 static int
1210 setescape(int argc, char *argv[])
1211 {
1212 	char *arg;
1213 	char buf[50];
1214 
1215 	printf(
1216 	    "Deprecated usage - please use 'set escape%s%s' in the future.\r\n",
1217 				(argc > 2)? " ":"", (argc > 2)? argv[1]: "");
1218 	if (argc > 2)
1219 		arg = argv[1];
1220 	else {
1221 		printf("new escape character: ");
1222 		fgets(buf, sizeof(buf), stdin);
1223 		arg = buf;
1224 	}
1225 	if (arg[0] != '\0')
1226 		escape = arg[0];
1227 	printf("Escape character is '%s'.\r\n", control(escape));
1228 
1229 	fflush(stdout);
1230 	return 1;
1231 }
1232 
1233 static int
1234 togcrmod()
1235 {
1236     crmod = !crmod;
1237     printf("Deprecated usage - please use 'toggle crmod' in the future.\r\n");
1238     printf("%s map carriage return on output.\r\n", crmod ? "Will" : "Won't");
1239     fflush(stdout);
1240     return 1;
1241 }
1242 
1243 static int
1244 telnetsuspend()
1245 {
1246 #ifdef	SIGTSTP
1247     setcommandmode();
1248     {
1249 	long oldrows, oldcols, newrows, newcols, err;
1250 
1251 	err = (TerminalWindowSize(&oldrows, &oldcols) == 0) ? 1 : 0;
1252 	kill(0, SIGTSTP);
1253 	/*
1254 	 * If we didn't get the window size before the SUSPEND, but we
1255 	 * can get them now (?), then send the NAWS to make sure that
1256 	 * we are set up for the right window size.
1257 	 */
1258 	if (TerminalWindowSize(&newrows, &newcols) && connected &&
1259 	    (err || ((oldrows != newrows) || (oldcols != newcols)))) {
1260 		sendnaws();
1261 	}
1262     }
1263     /* reget parameters in case they were changed */
1264     TerminalSaveState();
1265     setconnmode(0);
1266 #else
1267     printf("Suspend is not supported.  Try the '!' command instead\r\n");
1268 #endif
1269     return 1;
1270 }
1271 
1272 static int
1273 shell(int argc, char **argv)
1274 {
1275     long oldrows, oldcols, newrows, newcols, err;
1276 
1277     setcommandmode();
1278 
1279     err = (TerminalWindowSize(&oldrows, &oldcols) == 0) ? 1 : 0;
1280     switch(fork()) {
1281     case -1:
1282 	perror("Fork failed\r\n");
1283 	break;
1284 
1285     case 0:
1286 	{
1287 	    /*
1288 	     * Fire up the shell in the child.
1289 	     */
1290 	    char *shellp, *shellname;
1291 
1292 	    shellp = getenv("SHELL");
1293 	    if (shellp == NULL)
1294 		shellp = "/bin/sh";
1295 	    if ((shellname = strrchr(shellp, '/')) == 0)
1296 		shellname = shellp;
1297 	    else
1298 		shellname++;
1299 	    if (argc > 1)
1300 		execl(shellp, shellname, "-c", &saveline[1], NULL);
1301 	    else
1302 		execl(shellp, shellname, NULL);
1303 	    perror("Execl");
1304 	    _exit(1);
1305 	}
1306     default:
1307 	    wait((int *)0);	/* Wait for the shell to complete */
1308 
1309 	    if (TerminalWindowSize(&newrows, &newcols) && connected &&
1310 		(err || ((oldrows != newrows) || (oldcols != newcols)))) {
1311 		    sendnaws();
1312 	    }
1313 	    break;
1314     }
1315     return 1;
1316 }
1317 
1318 static int
1319 bye(int argc, char **argv)
1320 {
1321     if (connected) {
1322 	shutdown(net, 2);
1323 	printf("Connection closed.\r\n");
1324 	NetClose(net);
1325 	connected = 0;
1326 	resettermname = 1;
1327 #if	defined(AUTHENTICATION) || defined(ENCRYPTION)
1328 	auth_encrypt_connect(connected);
1329 #endif
1330 	/* reset options */
1331 	tninit();
1332     }
1333     if ((argc != 2) || (strcmp(argv[1], "fromquit") != 0))
1334 	longjmp(toplevel, 1);
1335     return 0;	/* NOTREACHED */
1336 }
1337 
1338 int
1339 quit(void)
1340 {
1341 	call(bye, "bye", "fromquit", 0);
1342 	Exit(0);
1343 	return 0; /*NOTREACHED*/
1344 }
1345 
1346 static int
1347 logout()
1348 {
1349 	send_do(TELOPT_LOGOUT, 1);
1350 	netflush();
1351 	return 1;
1352 }
1353 
1354 
1355 /*
1356  * The SLC command.
1357  */
1358 
1359 struct slclist {
1360 	char	*name;
1361 	char	*help;
1362 	void	(*handler)();
1363 	int	arg;
1364 };
1365 
1366 static void slc_help(void);
1367 
1368 struct slclist SlcList[] = {
1369     { "export",	"Use local special character definitions",
1370 						slc_mode_export,	0 },
1371     { "import",	"Use remote special character definitions",
1372 						slc_mode_import,	1 },
1373     { "check",	"Verify remote special character definitions",
1374 						slc_mode_import,	0 },
1375     { "help",	0,				slc_help,		0 },
1376     { "?",	"Print help information",	slc_help,		0 },
1377     { 0 },
1378 };
1379 
1380 static void
1381 slc_help(void)
1382 {
1383     struct slclist *c;
1384 
1385     for (c = SlcList; c->name; c++) {
1386 	if (c->help) {
1387 	    if (*c->help)
1388 		printf("%-15s %s\r\n", c->name, c->help);
1389 	    else
1390 		printf("\r\n");
1391 	}
1392     }
1393 }
1394 
1395 static struct slclist *
1396 getslc(char *name)
1397 {
1398     return (struct slclist *)
1399 		genget(name, (char **) SlcList, sizeof(struct slclist));
1400 }
1401 
1402 static int
1403 slccmd(int argc, char **argv)
1404 {
1405     struct slclist *c;
1406 
1407     if (argc != 2) {
1408 	fprintf(stderr,
1409 	    "Need an argument to 'slc' command.  'slc ?' for help.\r\n");
1410 	return 0;
1411     }
1412     c = getslc(argv[1]);
1413     if (c == 0) {
1414 	fprintf(stderr, "'%s': unknown argument ('slc ?' for help).\r\n",
1415     				argv[1]);
1416 	return 0;
1417     }
1418     if (Ambiguous(c)) {
1419 	fprintf(stderr, "'%s': ambiguous argument ('slc ?' for help).\r\n",
1420     				argv[1]);
1421 	return 0;
1422     }
1423     (*c->handler)(c->arg);
1424     slcstate();
1425     return 1;
1426 }
1427 
1428 /*
1429  * The ENVIRON command.
1430  */
1431 
1432 struct envlist {
1433 	char	*name;
1434 	char	*help;
1435 	void	(*handler)();
1436 	int	narg;
1437 };
1438 
1439 static void env_help (void);
1440 
1441 struct envlist EnvList[] = {
1442     { "define",	"Define an environment variable",
1443 						(void (*)())env_define,	2 },
1444     { "undefine", "Undefine an environment variable",
1445 						env_undefine,	1 },
1446     { "export",	"Mark an environment variable for automatic export",
1447 						env_export,	1 },
1448     { "unexport", "Don't mark an environment variable for automatic export",
1449 						env_unexport,	1 },
1450     { "send",	"Send an environment variable", env_send,	1 },
1451     { "list",	"List the current environment variables",
1452 						env_list,	0 },
1453     { "help",	0,				env_help,		0 },
1454     { "?",	"Print help information",	env_help,		0 },
1455     { 0 },
1456 };
1457 
1458 static void
1459 env_help()
1460 {
1461     struct envlist *c;
1462 
1463     for (c = EnvList; c->name; c++) {
1464 	if (c->help) {
1465 	    if (*c->help)
1466 		printf("%-15s %s\r\n", c->name, c->help);
1467 	    else
1468 		printf("\r\n");
1469 	}
1470     }
1471 }
1472 
1473 static struct envlist *
1474 getenvcmd(char *name)
1475 {
1476     return (struct envlist *)
1477 		genget(name, (char **) EnvList, sizeof(struct envlist));
1478 }
1479 
1480 static int
1481 env_cmd(int argc, char **argv)
1482 {
1483     struct envlist *c;
1484 
1485     if (argc < 2) {
1486 	fprintf(stderr,
1487 	    "Need an argument to 'environ' command.  'environ ?' for help.\r\n");
1488 	return 0;
1489     }
1490     c = getenvcmd(argv[1]);
1491     if (c == 0) {
1492 	fprintf(stderr, "'%s': unknown argument ('environ ?' for help).\r\n",
1493     				argv[1]);
1494 	return 0;
1495     }
1496     if (Ambiguous(c)) {
1497 	fprintf(stderr, "'%s': ambiguous argument ('environ ?' for help).\r\n",
1498     				argv[1]);
1499 	return 0;
1500     }
1501     if (c->narg + 2 != argc) {
1502 	fprintf(stderr,
1503 	    "Need %s%d argument%s to 'environ %s' command.  'environ ?' for help.\r\n",
1504 		c->narg < argc + 2 ? "only " : "",
1505 		c->narg, c->narg == 1 ? "" : "s", c->name);
1506 	return 0;
1507     }
1508     (*c->handler)(argv[2], argv[3]);
1509     return 1;
1510 }
1511 
1512 struct env_lst {
1513 	struct env_lst *next;	/* pointer to next structure */
1514 	struct env_lst *prev;	/* pointer to previous structure */
1515 	unsigned char *var;	/* pointer to variable name */
1516 	unsigned char *value;	/* pointer to variable value */
1517 	int export;		/* 1 -> export with default list of variables */
1518 	int welldefined;	/* A well defined variable */
1519 };
1520 
1521 struct env_lst envlisthead;
1522 
1523 struct env_lst *
1524 env_find(unsigned char *var)
1525 {
1526 	struct env_lst *ep;
1527 
1528 	for (ep = envlisthead.next; ep; ep = ep->next) {
1529 		if (strcmp((char *)ep->var, (char *)var) == 0)
1530 			return(ep);
1531 	}
1532 	return(NULL);
1533 }
1534 
1535 #if !HAVE_DECL_ENVIRON
1536 extern char **environ;
1537 #endif
1538 
1539 void
1540 env_init(void)
1541 {
1542 	char **epp, *cp;
1543 	struct env_lst *ep;
1544 
1545 	for (epp = environ; *epp; epp++) {
1546 		if ((cp = strchr(*epp, '='))) {
1547 			*cp = '\0';
1548 			ep = env_define((unsigned char *)*epp,
1549 					(unsigned char *)cp+1);
1550 			ep->export = 0;
1551 			*cp = '=';
1552 		}
1553 	}
1554 	/*
1555 	 * Special case for DISPLAY variable.  If it is ":0.0" or
1556 	 * "unix:0.0", we have to get rid of "unix" and insert our
1557 	 * hostname.
1558 	 */
1559 	if ((ep = env_find((unsigned char*)"DISPLAY"))
1560 	    && (*ep->value == ':'
1561 	    || strncmp((char *)ep->value, "unix:", 5) == 0)) {
1562 		char hbuf[256+1];
1563 		char *cp2 = strchr((char *)ep->value, ':');
1564 		int error;
1565 
1566 		/* XXX - should be k_gethostname? */
1567 		gethostname(hbuf, 256);
1568 		hbuf[256] = '\0';
1569 
1570 		/* If this is not the full name, try to get it via DNS */
1571 		if (strchr(hbuf, '.') == 0) {
1572 			struct addrinfo hints, *ai, *a;
1573 
1574 			memset (&hints, 0, sizeof(hints));
1575 			hints.ai_flags = AI_CANONNAME;
1576 
1577 			error = getaddrinfo (hbuf, NULL, &hints, &ai);
1578 			if (error == 0) {
1579 				for (a = ai; a != NULL; a = a->ai_next)
1580 					if (a->ai_canonname != NULL) {
1581 						strlcpy (hbuf,
1582 							 ai->ai_canonname,
1583 							 256);
1584 						break;
1585 					}
1586 				freeaddrinfo (ai);
1587 			}
1588 		}
1589 
1590 		error = asprintf (&cp, "%s%s", hbuf, cp2);
1591 		if (error != -1) {
1592 		    free (ep->value);
1593 		    ep->value = (unsigned char *)cp;
1594 		}
1595 	}
1596 	/*
1597 	 * If USER is not defined, but LOGNAME is, then add
1598 	 * USER with the value from LOGNAME.  By default, we
1599 	 * don't export the USER variable.
1600 	 */
1601 	if ((env_find((unsigned char*)"USER") == NULL) &&
1602 	    (ep = env_find((unsigned char*)"LOGNAME"))) {
1603 		env_define((unsigned char *)"USER", ep->value);
1604 		env_unexport((unsigned char *)"USER");
1605 	}
1606 	env_export((unsigned char *)"DISPLAY");
1607 	env_export((unsigned char *)"PRINTER");
1608 	env_export((unsigned char *)"XAUTHORITY");
1609 }
1610 
1611 struct env_lst *
1612 env_define(unsigned char *var, unsigned char *value)
1613 {
1614 	struct env_lst *ep;
1615 
1616 	if ((ep = env_find(var))) {
1617 		if (ep->var)
1618 			free(ep->var);
1619 		if (ep->value)
1620 			free(ep->value);
1621 	} else {
1622 		ep = (struct env_lst *)malloc(sizeof(struct env_lst));
1623 		ep->next = envlisthead.next;
1624 		envlisthead.next = ep;
1625 		ep->prev = &envlisthead;
1626 		if (ep->next)
1627 			ep->next->prev = ep;
1628 	}
1629 	ep->welldefined = opt_welldefined((char *)var);
1630 	ep->export = 1;
1631 	ep->var = (unsigned char *)strdup((char *)var);
1632 	ep->value = (unsigned char *)strdup((char *)value);
1633 	return(ep);
1634 }
1635 
1636 void
1637 env_undefine(unsigned char *var)
1638 {
1639 	struct env_lst *ep;
1640 
1641 	if ((ep = env_find(var))) {
1642 		ep->prev->next = ep->next;
1643 		if (ep->next)
1644 			ep->next->prev = ep->prev;
1645 		if (ep->var)
1646 			free(ep->var);
1647 		if (ep->value)
1648 			free(ep->value);
1649 		free(ep);
1650 	}
1651 }
1652 
1653 void
1654 env_export(unsigned char *var)
1655 {
1656 	struct env_lst *ep;
1657 
1658 	if ((ep = env_find(var)))
1659 		ep->export = 1;
1660 }
1661 
1662 void
1663 env_unexport(unsigned char *var)
1664 {
1665 	struct env_lst *ep;
1666 
1667 	if ((ep = env_find(var)))
1668 		ep->export = 0;
1669 }
1670 
1671 void
1672 env_send(unsigned char *var)
1673 {
1674 	struct env_lst *ep;
1675 
1676 	if (my_state_is_wont(TELOPT_NEW_ENVIRON)
1677 #ifdef	OLD_ENVIRON
1678 	    && my_state_is_wont(TELOPT_OLD_ENVIRON)
1679 #endif
1680 		) {
1681 		fprintf(stderr,
1682 		    "Cannot send '%s': Telnet ENVIRON option not enabled\r\n",
1683 									var);
1684 		return;
1685 	}
1686 	ep = env_find(var);
1687 	if (ep == 0) {
1688 		fprintf(stderr, "Cannot send '%s': variable not defined\r\n",
1689 									var);
1690 		return;
1691 	}
1692 	env_opt_start_info();
1693 	env_opt_add(ep->var);
1694 	env_opt_end(0);
1695 }
1696 
1697 void
1698 env_list(void)
1699 {
1700 	struct env_lst *ep;
1701 
1702 	for (ep = envlisthead.next; ep; ep = ep->next) {
1703 		printf("%c %-20s %s\r\n", ep->export ? '*' : ' ',
1704 					ep->var, ep->value);
1705 	}
1706 }
1707 
1708 unsigned char *
1709 env_default(int init, int welldefined)
1710 {
1711 	static struct env_lst *nep = NULL;
1712 
1713 	if (init) {
1714 		nep = &envlisthead;
1715 		return NULL;
1716 	}
1717 	if (nep) {
1718 		while ((nep = nep->next)) {
1719 			if (nep->export && (nep->welldefined == welldefined))
1720 				return(nep->var);
1721 		}
1722 	}
1723 	return(NULL);
1724 }
1725 
1726 unsigned char *
1727 env_getvalue(unsigned char *var)
1728 {
1729 	struct env_lst *ep;
1730 
1731 	if ((ep = env_find(var)))
1732 		return(ep->value);
1733 	return(NULL);
1734 }
1735 
1736 
1737 #if	defined(AUTHENTICATION)
1738 /*
1739  * The AUTHENTICATE command.
1740  */
1741 
1742 struct authlist {
1743 	char	*name;
1744 	char	*help;
1745 	int	(*handler)();
1746 	int	narg;
1747 };
1748 
1749 static int
1750 	auth_help (void);
1751 
1752 struct authlist AuthList[] = {
1753     { "status",	"Display current status of authentication information",
1754 						auth_status,	0 },
1755     { "disable", "Disable an authentication type ('auth disable ?' for more)",
1756 						auth_disable,	1 },
1757     { "enable", "Enable an authentication type ('auth enable ?' for more)",
1758 						auth_enable,	1 },
1759     { "help",	0,				auth_help,		0 },
1760     { "?",	"Print help information",	auth_help,		0 },
1761     { 0 },
1762 };
1763 
1764 static int
1765 auth_help()
1766 {
1767     struct authlist *c;
1768 
1769     for (c = AuthList; c->name; c++) {
1770 	if (c->help) {
1771 	    if (*c->help)
1772 		printf("%-15s %s\r\n", c->name, c->help);
1773 	    else
1774 		printf("\r\n");
1775 	}
1776     }
1777     return 0;
1778 }
1779 
1780 static int
1781 auth_cmd(int argc, char **argv)
1782 {
1783     struct authlist *c;
1784 
1785     if (argc < 2) {
1786 	fprintf(stderr,
1787 	    "Need an argument to 'auth' command.  'auth ?' for help.\r\n");
1788 	return 0;
1789     }
1790 
1791     c = (struct authlist *)
1792 		genget(argv[1], (char **) AuthList, sizeof(struct authlist));
1793     if (c == 0) {
1794 	fprintf(stderr, "'%s': unknown argument ('auth ?' for help).\r\n",
1795     				argv[1]);
1796 	return 0;
1797     }
1798     if (Ambiguous(c)) {
1799 	fprintf(stderr, "'%s': ambiguous argument ('auth ?' for help).\r\n",
1800     				argv[1]);
1801 	return 0;
1802     }
1803     if (c->narg + 2 != argc) {
1804 	fprintf(stderr,
1805 	    "Need %s%d argument%s to 'auth %s' command.  'auth ?' for help.\r\n",
1806 		c->narg < argc + 2 ? "only " : "",
1807 		c->narg, c->narg == 1 ? "" : "s", c->name);
1808 	return 0;
1809     }
1810     return((*c->handler)(argv[2], argv[3]));
1811 }
1812 #endif
1813 
1814 
1815 #if	defined(ENCRYPTION)
1816 /*
1817  * The ENCRYPT command.
1818  */
1819 
1820 struct encryptlist {
1821 	char	*name;
1822 	char	*help;
1823 	int	(*handler)();
1824 	int	needconnect;
1825 	int	minarg;
1826 	int	maxarg;
1827 };
1828 
1829 static int
1830 	EncryptHelp (void);
1831 
1832 struct encryptlist EncryptList[] = {
1833     { "enable", "Enable encryption. ('encrypt enable ?' for more)",
1834 						EncryptEnable, 1, 1, 2 },
1835     { "disable", "Disable encryption. ('encrypt enable ?' for more)",
1836 						EncryptDisable, 0, 1, 2 },
1837     { "type", "Set encryptiong type. ('encrypt type ?' for more)",
1838 						EncryptType, 0, 1, 1 },
1839     { "start", "Start encryption. ('encrypt start ?' for more)",
1840 						EncryptStart, 1, 0, 1 },
1841     { "stop", "Stop encryption. ('encrypt stop ?' for more)",
1842 						EncryptStop, 1, 0, 1 },
1843     { "input", "Start encrypting the input stream",
1844 						EncryptStartInput, 1, 0, 0 },
1845     { "-input", "Stop encrypting the input stream",
1846 						EncryptStopInput, 1, 0, 0 },
1847     { "output", "Start encrypting the output stream",
1848 						EncryptStartOutput, 1, 0, 0 },
1849     { "-output", "Stop encrypting the output stream",
1850 						EncryptStopOutput, 1, 0, 0 },
1851 
1852     { "status",	"Display current status of authentication information",
1853 						EncryptStatus,	0, 0, 0 },
1854     { "help",	0,				EncryptHelp,	0, 0, 0 },
1855     { "?",	"Print help information",	EncryptHelp,	0, 0, 0 },
1856     { 0 },
1857 };
1858 
1859 static int
1860 EncryptHelp()
1861 {
1862     struct encryptlist *c;
1863 
1864     for (c = EncryptList; c->name; c++) {
1865 	if (c->help) {
1866 	    if (*c->help)
1867 		printf("%-15s %s\r\n", c->name, c->help);
1868 	    else
1869 		printf("\r\n");
1870 	}
1871     }
1872     return 0;
1873 }
1874 
1875 static int
1876 encrypt_cmd(int argc, char **argv)
1877 {
1878     struct encryptlist *c;
1879 
1880     c = (struct encryptlist *)
1881 		genget(argv[1], (char **) EncryptList, sizeof(struct encryptlist));
1882     if (c == 0) {
1883         fprintf(stderr, "'%s': unknown argument ('encrypt ?' for help).\r\n",
1884     				argv[1]);
1885         return 0;
1886     }
1887     if (Ambiguous(c)) {
1888         fprintf(stderr, "'%s': ambiguous argument ('encrypt ?' for help).\r\n",
1889     				argv[1]);
1890         return 0;
1891     }
1892     argc -= 2;
1893     if (argc < c->minarg || argc > c->maxarg) {
1894 	if (c->minarg == c->maxarg) {
1895 	    fprintf(stderr, "Need %s%d argument%s ",
1896 		c->minarg < argc ? "only " : "", c->minarg,
1897 		c->minarg == 1 ? "" : "s");
1898 	} else {
1899 	    fprintf(stderr, "Need %s%d-%d arguments ",
1900 		c->maxarg < argc ? "only " : "", c->minarg, c->maxarg);
1901 	}
1902 	fprintf(stderr, "to 'encrypt %s' command.  'encrypt ?' for help.\r\n",
1903 		c->name);
1904 	return 0;
1905     }
1906     if (c->needconnect && !connected) {
1907 	if (!(argc && (isprefix(argv[2], "help") || isprefix(argv[2], "?")))) {
1908 	    printf("?Need to be connected first.\r\n");
1909 	    return 0;
1910 	}
1911     }
1912     return ((*c->handler)(argc > 0 ? argv[2] : 0,
1913 			argc > 1 ? argv[3] : 0,
1914 			argc > 2 ? argv[4] : 0));
1915 }
1916 #endif
1917 
1918 
1919 /*
1920  * Print status about the connection.
1921  */
1922 
1923 static int
1924 status(int argc, char **argv)
1925 {
1926     if (connected) {
1927 	printf("Connected to %s.\r\n", hostname);
1928 	if ((argc < 2) || strcmp(argv[1], "notmuch")) {
1929 	    int mode = getconnmode();
1930 
1931 	    if (my_want_state_is_will(TELOPT_LINEMODE)) {
1932 		printf("Operating with LINEMODE option\r\n");
1933 		printf("%s line editing\r\n", (mode&MODE_EDIT) ? "Local" : "No");
1934 		printf("%s catching of signals\r\n",
1935 					(mode&MODE_TRAPSIG) ? "Local" : "No");
1936 		slcstate();
1937 #ifdef	KLUDGELINEMODE
1938 	    } else if (kludgelinemode && my_want_state_is_dont(TELOPT_SGA)) {
1939 		printf("Operating in obsolete linemode\r\n");
1940 #endif
1941 	    } else {
1942 		printf("Operating in single character mode\r\n");
1943 		if (localchars)
1944 		    printf("Catching signals locally\r\n");
1945 	    }
1946 	    printf("%s character echo\r\n", (mode&MODE_ECHO) ? "Local" : "Remote");
1947 	    if (my_want_state_is_will(TELOPT_LFLOW))
1948 		printf("%s flow control\r\n", (mode&MODE_FLOW) ? "Local" : "No");
1949 #if	defined(ENCRYPTION)
1950 	    encrypt_display();
1951 #endif
1952 	}
1953     } else {
1954 	printf("No connection.\r\n");
1955     }
1956     printf("Escape character is '%s'.\r\n", control(escape));
1957     fflush(stdout);
1958     return 1;
1959 }
1960 
1961 #ifdef	SIGINFO
1962 /*
1963  * Function that gets called when SIGINFO is received.
1964  */
1965 RETSIGTYPE
1966 ayt_status(int ignore)
1967 {
1968     call(status, "status", "notmuch", 0);
1969 }
1970 #endif
1971 
1972 static Command *getcmd(char *name);
1973 
1974 static void
1975 cmdrc(char *m1, char *m2)
1976 {
1977     static char rcname[128];
1978     Command *c;
1979     FILE *rcfile;
1980     int gotmachine = 0;
1981     int l1 = strlen(m1);
1982     int l2 = strlen(m2);
1983     char m1save[64];
1984 
1985     if (skiprc)
1986 	return;
1987 
1988     strlcpy(m1save, m1, sizeof(m1save));
1989     m1 = m1save;
1990 
1991     if (rcname[0] == 0) {
1992 	char *home = getenv("HOME");
1993 
1994 	snprintf (rcname, sizeof(rcname), "%s/.telnetrc",
1995 		  home ? home : "");
1996     }
1997 
1998     if ((rcfile = fopen(rcname, "r")) == 0) {
1999 	return;
2000     }
2001 
2002     for (;;) {
2003 	if (fgets(line, sizeof(line), rcfile) == NULL)
2004 	    break;
2005 	if (line[0] == 0)
2006 	    break;
2007 	if (line[0] == '#')
2008 	    continue;
2009 	if (gotmachine) {
2010 	    if (!isspace((unsigned char)line[0]))
2011 		gotmachine = 0;
2012 	}
2013 	if (gotmachine == 0) {
2014 	    if (isspace((unsigned char)line[0]))
2015 		continue;
2016 	    if (strncasecmp(line, m1, l1) == 0)
2017 		strncpy(line, &line[l1], sizeof(line) - l1);
2018 	    else if (strncasecmp(line, m2, l2) == 0)
2019 		strncpy(line, &line[l2], sizeof(line) - l2);
2020 	    else if (strncasecmp(line, "DEFAULT", 7) == 0)
2021 		strncpy(line, &line[7], sizeof(line) - 7);
2022 	    else
2023 		continue;
2024 	    if (line[0] != ' ' && line[0] != '\t' && line[0] != '\n')
2025 		continue;
2026 	    gotmachine = 1;
2027 	}
2028 	makeargv();
2029 	if (margv[0] == 0)
2030 	    continue;
2031 	c = getcmd(margv[0]);
2032 	if (Ambiguous(c)) {
2033 	    printf("?Ambiguous command: %s\r\n", margv[0]);
2034 	    continue;
2035 	}
2036 	if (c == 0) {
2037 	    printf("?Invalid command: %s\r\n", margv[0]);
2038 	    continue;
2039 	}
2040 	/*
2041 	 * This should never happen...
2042 	 */
2043 	if (c->needconnect && !connected) {
2044 	    printf("?Need to be connected first for %s.\r\n", margv[0]);
2045 	    continue;
2046 	}
2047 	(*c->handler)(margc, margv);
2048     }
2049     fclose(rcfile);
2050 }
2051 
2052 int
2053 tn(int argc, char **argv)
2054 {
2055     struct servent *sp = 0;
2056     char *cmd, *hostp = 0, *portp = 0;
2057     char *user = 0;
2058     int port = 0;
2059 
2060     /* clear the socket address prior to use */
2061 
2062     if (connected) {
2063 	printf("?Already connected to %s\r\n", hostname);
2064 	return 0;
2065     }
2066     if (argc < 2) {
2067 	strlcpy(line, "open ", sizeof(line));
2068 	printf("(to) ");
2069 	fgets(&line[strlen(line)], sizeof(line) - strlen(line), stdin);
2070 	makeargv();
2071 	argc = margc;
2072 	argv = margv;
2073     }
2074     cmd = *argv;
2075     --argc; ++argv;
2076     while (argc) {
2077 	if (strcmp(*argv, "help") == 0 || isprefix(*argv, "?"))
2078 	    goto usage;
2079 	if (strcmp(*argv, "-l") == 0) {
2080 	    --argc; ++argv;
2081 	    if (argc == 0)
2082 		goto usage;
2083 	    user = strdup(*argv++);
2084 	    --argc;
2085 	    continue;
2086 	}
2087 	if (strcmp(*argv, "-a") == 0) {
2088 	    --argc; ++argv;
2089 	    autologin = 1;
2090 	    continue;
2091 	}
2092 	if (hostp == 0) {
2093 	    hostp = *argv++;
2094 	    --argc;
2095 	    continue;
2096 	}
2097 	if (portp == 0) {
2098 	    portp = *argv++;
2099 	    --argc;
2100 	    continue;
2101 	}
2102     usage:
2103 	printf("usage: %s [-l user] [-a] host-name [port]\r\n", cmd);
2104 	return 0;
2105     }
2106     if (hostp == 0)
2107 	goto usage;
2108 
2109     strlcpy (_hostname, hostp, sizeof(_hostname));
2110     hostp = _hostname;
2111     if (hostp[0] == '@' || hostp[0] == '!') {
2112 	char *p;
2113 	hostname = NULL;
2114 	for (p = hostp + 1; *p; p++) {
2115 	    if (*p == ',' || *p == '@')
2116 		hostname = p;
2117 	}
2118 	if (hostname == NULL) {
2119 	    fprintf(stderr, "%s: bad source route specification\n", hostp);
2120 	    return 0;
2121 	}
2122 	*hostname++ = '\0';
2123     } else
2124 	hostname = hostp;
2125 
2126     if (portp) {
2127 	if (*portp == '-') {
2128 	    portp++;
2129 	    telnetport = 1;
2130 	} else
2131 	    telnetport = 0;
2132 	port = atoi(portp);
2133 	if (port == 0) {
2134 	    sp = roken_getservbyname(portp, "tcp");
2135 	    if (sp)
2136 		port = sp->s_port;
2137 	    else {
2138 		printf("%s: bad port number\r\n", portp);
2139 		return 0;
2140 	    }
2141 	} else {
2142 	    port = htons(port);
2143 	}
2144     } else {
2145 	if (sp == 0) {
2146 	    sp = roken_getservbyname("telnet", "tcp");
2147 	    if (sp == 0) {
2148 		fprintf(stderr, "telnet: tcp/telnet: unknown service\r\n");
2149 		return 0;
2150 	    }
2151 	    port = sp->s_port;
2152 	}
2153 	telnetport = 1;
2154     }
2155 
2156     {
2157 	struct addrinfo *ai, *a, hints;
2158 	int error;
2159 	char portstr[NI_MAXSERV];
2160 
2161 	memset (&hints, 0, sizeof(hints));
2162 	hints.ai_socktype = SOCK_STREAM;
2163 	hints.ai_protocol = IPPROTO_TCP;
2164 	hints.ai_flags    = AI_CANONNAME;
2165 
2166 	snprintf (portstr, sizeof(portstr), "%u", ntohs(port));
2167 
2168 	error = getaddrinfo (hostname, portstr, &hints, &ai);
2169 	if (error) {
2170 	    fprintf (stderr, "%s: %s\r\n", hostname, gai_strerror (error));
2171 	    return 0;
2172 	}
2173 
2174 	for (a = ai; a != NULL && connected == 0; a = a->ai_next) {
2175 	    char addrstr[256];
2176 
2177 	    if (a->ai_canonname != NULL)
2178 		strlcpy (_hostname, a->ai_canonname, sizeof(_hostname));
2179 
2180 	    if (getnameinfo (a->ai_addr, a->ai_addrlen,
2181 			     addrstr, sizeof(addrstr),
2182 			     NULL, 0, NI_NUMERICHOST) != 0)
2183 		strlcpy (addrstr, "unknown address", sizeof(addrstr));
2184 
2185 	    printf("Trying %s...\r\n", addrstr);
2186 
2187 	    net = socket (a->ai_family, a->ai_socktype, a->ai_protocol);
2188 	    if (net < 0) {
2189 		warn ("socket");
2190 		continue;
2191 	    }
2192 
2193 #if	defined(IP_OPTIONS) && defined(IPPROTO_IP) && defined(HAVE_SETSOCKOPT)
2194 	if (hostp[0] == '@' || hostp[0] == '!') {
2195 	    char *srp = 0;
2196 	    int srlen;
2197 	    int proto, opt;
2198 
2199 	    if ((srlen = sourceroute(a, hostp, &srp, &proto, &opt)) < 0) {
2200 		(void) NetClose(net);
2201 		net = -1;
2202 		continue;
2203 	    }
2204 	    if (srp && setsockopt(net, proto, opt, srp, srlen) < 0)
2205 		perror("setsockopt (source route)");
2206 	}
2207 #endif
2208 
2209 #if	defined(IPPROTO_IP) && defined(IP_TOS)
2210 	    if (a->ai_family == AF_INET) {
2211 # if	defined(HAVE_GETTOSBYNAME)
2212 		struct tosent *tp;
2213 		if (tos < 0 && (tp = gettosbyname("telnet", "tcp")))
2214 		    tos = tp->t_tos;
2215 # endif
2216 		if (tos < 0)
2217 		    tos = 020;	/* Low Delay bit */
2218 		if (tos
2219 		    && (setsockopt(net, IPPROTO_IP, IP_TOS,
2220 				   (void *)&tos, sizeof(int)) < 0)
2221 		    && (errno != ENOPROTOOPT))
2222 		    perror("telnet: setsockopt (IP_TOS) (ignored)");
2223 	    }
2224 #endif	/* defined(IPPROTO_IP) && defined(IP_TOS) */
2225 	    if (debug && SetSockOpt(net, SOL_SOCKET, SO_DEBUG, 1) < 0) {
2226 		perror("setsockopt (SO_DEBUG)");
2227 	    }
2228 
2229 	    if (connect (net, a->ai_addr, a->ai_addrlen) < 0) {
2230 		fprintf (stderr, "telnet: connect to address %s: %s\n",
2231 			 addrstr, strerror(errno));
2232 		NetClose(net);
2233 		if (a->ai_next != NULL) {
2234 		    continue;
2235 		} else {
2236 		    freeaddrinfo (ai);
2237 		    return 0;
2238 		}
2239 	    }
2240 	    ++connected;
2241 #if	defined(AUTHENTICATION) || defined(ENCRYPTION)
2242 	    auth_encrypt_connect(connected);
2243 #endif
2244 	}
2245 	freeaddrinfo (ai);
2246 	if (connected == 0)
2247 	    return 0;
2248     }
2249     cmdrc(hostp, hostname);
2250     set_forward_options();
2251     if (autologin && user == NULL)
2252 	user = (char *)get_default_username ();
2253     if (user) {
2254 	env_define((unsigned char *)"USER", (unsigned char *)user);
2255 	env_export((unsigned char *)"USER");
2256     }
2257     call(status, "status", "notmuch", 0);
2258     if (setjmp(peerdied) == 0)
2259 	my_telnet((char *)user);
2260     NetClose(net);
2261     ExitString("Connection closed by foreign host.\r\n",1);
2262     /*NOTREACHED*/
2263     return 0;
2264 }
2265 
2266 #define HELPINDENT ((int)sizeof ("connect"))
2267 
2268 static char
2269 	openhelp[] =	"connect to a site",
2270 	closehelp[] =	"close current connection",
2271 	logouthelp[] =	"forcibly logout remote user and close the connection",
2272 	quithelp[] =	"exit telnet",
2273 	statushelp[] =	"print status information",
2274 	helphelp[] =	"print help information",
2275 	sendhelp[] =	"transmit special characters ('send ?' for more)",
2276 	sethelp[] = 	"set operating parameters ('set ?' for more)",
2277 	unsethelp[] = 	"unset operating parameters ('unset ?' for more)",
2278 	togglestring[] ="toggle operating parameters ('toggle ?' for more)",
2279 	slchelp[] =	"change state of special charaters ('slc ?' for more)",
2280 	displayhelp[] =	"display operating parameters",
2281 #if	defined(AUTHENTICATION)
2282 	authhelp[] =	"turn on (off) authentication ('auth ?' for more)",
2283 #endif
2284 #if	defined(ENCRYPTION)
2285 	encrypthelp[] =	"turn on (off) encryption ('encrypt ?' for more)",
2286 #endif
2287 	zhelp[] =	"suspend telnet",
2288 	shellhelp[] =	"invoke a subshell",
2289 	envhelp[] =	"change environment variables ('environ ?' for more)",
2290 	modestring[] = "try to enter line or character mode ('mode ?' for more)";
2291 
2292 static int help(int argc, char **argv);
2293 
2294 static Command cmdtab[] = {
2295 	{ "close",	closehelp,	bye,		1 },
2296 	{ "logout",	logouthelp,	logout,		1 },
2297 	{ "display",	displayhelp,	display,	0 },
2298 	{ "mode",	modestring,	modecmd,	0 },
2299 	{ "open",	openhelp,	tn,		0 },
2300 	{ "quit",	quithelp,	quit,		0 },
2301 	{ "send",	sendhelp,	sendcmd,	0 },
2302 	{ "set",	sethelp,	setcmd,		0 },
2303 	{ "unset",	unsethelp,	unsetcmd,	0 },
2304 	{ "status",	statushelp,	status,		0 },
2305 	{ "toggle",	togglestring,	toggle,		0 },
2306 	{ "slc",	slchelp,	slccmd,		0 },
2307 #if	defined(AUTHENTICATION)
2308 	{ "auth",	authhelp,	auth_cmd,	0 },
2309 #endif
2310 #if	defined(ENCRYPTION)
2311 	{ "encrypt",	encrypthelp,	encrypt_cmd,	0 },
2312 #endif
2313 	{ "z",		zhelp,		telnetsuspend,	0 },
2314 	{ "!",		shellhelp,	shell,		0 },
2315 	{ "environ",	envhelp,	env_cmd,	0 },
2316 	{ "?",		helphelp,	help,		0 },
2317 	{ 0,            0,              0,              0 }
2318 };
2319 
2320 static char	crmodhelp[] =	"deprecated command -- use 'toggle crmod' instead";
2321 static char	escapehelp[] =	"deprecated command -- use 'set escape' instead";
2322 
2323 static Command cmdtab2[] = {
2324 	{ "help",	0,		help,		0 },
2325 	{ "escape",	escapehelp,	setescape,	0 },
2326 	{ "crmod",	crmodhelp,	togcrmod,	0 },
2327 	{ 0,            0,		0, 		0 }
2328 };
2329 
2330 
2331 /*
2332  * Call routine with argc, argv set from args (terminated by 0).
2333  */
2334 
2335 static int
2336 call(intrtn_t routine, ...)
2337 {
2338     va_list ap;
2339     char *args[100];
2340     int argno = 0;
2341 
2342     va_start(ap, routine);
2343     while ((args[argno++] = va_arg(ap, char *)) != 0);
2344     va_end(ap);
2345     return (*routine)(argno-1, args);
2346 }
2347 
2348 
2349 static Command
2350 *getcmd(char *name)
2351 {
2352     Command *cm;
2353 
2354     if ((cm = (Command *) genget(name, (char **) cmdtab, sizeof(Command))))
2355 	return cm;
2356     return (Command *) genget(name, (char **) cmdtab2, sizeof(Command));
2357 }
2358 
2359 void
2360 command(int top, char *tbuf, int cnt)
2361 {
2362     Command *c;
2363 
2364     setcommandmode();
2365     if (!top) {
2366 	putchar('\n');
2367     } else {
2368 	signal(SIGINT, SIG_DFL);
2369 	signal(SIGQUIT, SIG_DFL);
2370     }
2371     for (;;) {
2372 	if (rlogin == _POSIX_VDISABLE)
2373 		printf("%s> ", prompt);
2374 	if (tbuf) {
2375 	    char *cp;
2376 	    cp = line;
2377 	    while (cnt > 0 && (*cp++ = *tbuf++) != '\n')
2378 		cnt--;
2379 	    tbuf = 0;
2380 	    if (cp == line || *--cp != '\n' || cp == line)
2381 		goto getline;
2382 	    *cp = '\0';
2383 	    if (rlogin == _POSIX_VDISABLE)
2384 		printf("%s\r\n", line);
2385 	} else {
2386 	getline:
2387 	    if (rlogin != _POSIX_VDISABLE)
2388 		printf("%s> ", prompt);
2389 	    if (fgets(line, sizeof(line), stdin) == NULL) {
2390 		if (feof(stdin) || ferror(stdin)) {
2391 		    quit();
2392 		    /*NOTREACHED*/
2393 		}
2394 		break;
2395 	    }
2396 	}
2397 	if (line[0] == 0)
2398 	    break;
2399 	makeargv();
2400 	if (margv[0] == 0) {
2401 	    break;
2402 	}
2403 	c = getcmd(margv[0]);
2404 	if (Ambiguous(c)) {
2405 	    printf("?Ambiguous command\r\n");
2406 	    continue;
2407 	}
2408 	if (c == 0) {
2409 	    printf("?Invalid command\r\n");
2410 	    continue;
2411 	}
2412 	if (c->needconnect && !connected) {
2413 	    printf("?Need to be connected first.\r\n");
2414 	    continue;
2415 	}
2416 	if ((*c->handler)(margc, margv)) {
2417 	    break;
2418 	}
2419     }
2420     if (!top) {
2421 	if (!connected) {
2422 	    longjmp(toplevel, 1);
2423 	    /*NOTREACHED*/
2424 	}
2425 	setconnmode(0);
2426     }
2427 }
2428 
2429 /*
2430  * Help command.
2431  */
2432 static int
2433 help(int argc, char **argv)
2434 {
2435 	Command *c;
2436 
2437 	if (argc == 1) {
2438 		printf("Commands may be abbreviated.  Commands are:\r\n\r\n");
2439 		for (c = cmdtab; c->name; c++)
2440 			if (c->help) {
2441 				printf("%-*s\t%s\r\n", HELPINDENT, c->name,
2442 								    c->help);
2443 			}
2444 		return 0;
2445 	}
2446 	while (--argc > 0) {
2447 		char *arg;
2448 		arg = *++argv;
2449 		c = getcmd(arg);
2450 		if (Ambiguous(c))
2451 			printf("?Ambiguous help command %s\r\n", arg);
2452 		else if (c == (Command *)0)
2453 			printf("?Invalid help command %s\r\n", arg);
2454 		else
2455 			printf("%s\r\n", c->help);
2456 	}
2457 	return 0;
2458 }
2459 
2460 
2461 #if	defined(IP_OPTIONS) && defined(IPPROTO_IP)
2462 
2463 /*
2464  * Source route is handed in as
2465  *	[!]@hop1@hop2...@dst
2466  *
2467  * If the leading ! is present, it is a strict source route, otherwise it is
2468  * assmed to be a loose source route.  Note that leading ! is effective
2469  * only for IPv4 case.
2470  *
2471  * We fill in the source route option as
2472  *	hop1,hop2,hop3...dest
2473  * and return a pointer to hop1, which will
2474  * be the address to connect() to.
2475  *
2476  * Arguments:
2477  *	ai:	The address (by struct addrinfo) for the final destination.
2478  *
2479  *	arg:	Pointer to route list to decipher
2480  *
2481  *	cpp: 	Pointer to a pointer, so that sourceroute() can return
2482  *		the address of result buffer (statically alloc'ed).
2483  *
2484  *	protop/optp:
2485  *		Pointer to an integer.  The pointed variable
2486  *	lenp:	pointer to an integer that contains the
2487  *		length of *cpp if *cpp != NULL.
2488  *
2489  * Return values:
2490  *
2491  *	Returns the length of the option pointed to by *cpp.  If the
2492  *	return value is -1, there was a syntax error in the
2493  *	option, either arg contained unknown characters or too many hosts,
2494  *	or hostname cannot be resolved.
2495  *
2496  *	The caller needs to pass return value (len), *cpp, *protop and *optp
2497  *	to setsockopt(2).
2498  *
2499  *	*cpp:	Points to the result buffer.  The region is statically
2500  *		allocated by the function.
2501  *
2502  *	*protop:
2503  *		protocol # to be passed to setsockopt(2).
2504  *
2505  *	*optp:	option # to be passed to setsockopt(2).
2506  *
2507  */
2508 int
2509 sourceroute(struct addrinfo *ai,
2510 	    char *arg,
2511 	    char **cpp,
2512 	    int *protop,
2513 	    int *optp)
2514 {
2515 	char *cp, *cp2, *lsrp = NULL, *lsrep = NULL;
2516 	struct addrinfo hints, *res;
2517 	int len, error;
2518 	struct sockaddr_in *sin;
2519 	register char c;
2520 	static char lsr[44];
2521 #ifdef INET6
2522 	struct cmsghdr *cmsg = NULL;
2523 	struct sockaddr_in6 *sin6;
2524 	static char rhbuf[1024];
2525 #endif
2526 
2527 	/*
2528 	 * Verify the arguments.
2529 	 */
2530 	if (cpp == NULL)
2531 		return -1;
2532 
2533 	cp = arg;
2534 
2535 	*cpp = NULL;
2536 	switch (ai->ai_family) {
2537 	case AF_INET:
2538 		lsrp = lsr;
2539 		lsrep = lsrp + sizeof(lsr);
2540 
2541 		/*
2542 		 * Next, decide whether we have a loose source
2543 		 * route or a strict source route, and fill in
2544 		 * the begining of the option.
2545 		 */
2546 		if (*cp == '!') {
2547 			cp++;
2548 			*lsrp++ = IPOPT_SSRR;
2549 		} else
2550 			*lsrp++ = IPOPT_LSRR;
2551 		if (*cp != '@')
2552 			return -1;
2553 		lsrp++;		/* skip over length, we'll fill it in later */
2554 		*lsrp++ = 4;
2555 		cp++;
2556 		*protop = IPPROTO_IP;
2557 		*optp = IP_OPTIONS;
2558 		break;
2559 #ifdef INET6
2560 	case AF_INET6:
2561 /* this needs to be updated for rfc2292bis */
2562 #ifdef IPV6_PKTOPTIONS
2563 		cmsg = inet6_rthdr_init(rhbuf, IPV6_RTHDR_TYPE_0);
2564 		if (*cp != '@')
2565 			return -1;
2566 		cp++;
2567 		*protop = IPPROTO_IPV6;
2568 		*optp = IPV6_PKTOPTIONS;
2569 		break;
2570 #else
2571 		return -1;
2572 #endif
2573 #endif
2574 	default:
2575 		return -1;
2576 	}
2577 
2578 	memset(&hints, 0, sizeof(hints));
2579 	hints.ai_family = ai->ai_family;
2580 	hints.ai_socktype = SOCK_STREAM;
2581 
2582 	for (c = 0;;) {
2583 		if (c == ':')
2584 			cp2 = 0;
2585 		else for (cp2 = cp; (c = *cp2) != '\0'; cp2++) {
2586 			if (c == ',') {
2587 				*cp2++ = '\0';
2588 				if (*cp2 == '@')
2589 					cp2++;
2590 			} else if (c == '@') {
2591 				*cp2++ = '\0';
2592 			}
2593 #if 0	/*colon conflicts with IPv6 address*/
2594 			else if (c == ':') {
2595 				*cp2++ = '\0';
2596 			}
2597 #endif
2598 			else
2599 				continue;
2600 			break;
2601 		}
2602 		if (!c)
2603 			cp2 = 0;
2604 
2605 		error = getaddrinfo(cp, NULL, &hints, &res);
2606 		if (error) {
2607 			fprintf(stderr, "%s: %s\n", cp, gai_strerror(error));
2608 			return -1;
2609 		}
2610 		if (ai->ai_family != res->ai_family) {
2611 			freeaddrinfo(res);
2612 			return -1;
2613 		}
2614 		if (ai->ai_family == AF_INET) {
2615 			/*
2616 			 * Check to make sure there is space for address
2617 			 */
2618 			if (lsrp + 4 > lsrep) {
2619 				freeaddrinfo(res);
2620 				return -1;
2621 			}
2622 			sin = (struct sockaddr_in *)res->ai_addr;
2623 			memcpy(lsrp, &sin->sin_addr, sizeof(struct in_addr));
2624 			lsrp += sizeof(struct in_addr);
2625 		}
2626 #ifdef INET6
2627 		else if (ai->ai_family == AF_INET6) {
2628 			sin6 = (struct sockaddr_in6 *)res->ai_addr;
2629 			inet6_rthdr_add(cmsg, &sin6->sin6_addr,
2630 				IPV6_RTHDR_LOOSE);
2631 		}
2632 #endif
2633 		else {
2634 			freeaddrinfo(res);
2635 			return -1;
2636 		}
2637 		freeaddrinfo(res);
2638 		if (cp2)
2639 			cp = cp2;
2640 		else
2641 			break;
2642 	}
2643 	if (ai->ai_family == AF_INET) {
2644 		/* record the last hop */
2645 		if (lsrp + 4 > lsrep)
2646 			return -1;
2647 		sin = (struct sockaddr_in *)ai->ai_addr;
2648 		memcpy(lsrp, &sin->sin_addr, sizeof(struct in_addr));
2649 		lsrp += sizeof(struct in_addr);
2650 #ifndef	sysV88
2651 		lsr[IPOPT_OLEN] = lsrp - lsr;
2652 		if (lsr[IPOPT_OLEN] <= 7 || lsr[IPOPT_OLEN] > 40)
2653 			return -1;
2654 		*lsrp++ = IPOPT_NOP;	/*32bit word align*/
2655 		len = lsrp - lsr;
2656 		*cpp = lsr;
2657 #else
2658 		ipopt.io_len = lsrp - lsr;
2659 		if (ipopt.io_len <= 5)	/*is 3 better?*/
2660 			return -1;
2661 		*cpp = (char 8)&ipopt;
2662 #endif
2663 	}
2664 #ifdef INET6
2665 	else if (ai->ai_family == AF_INET6) {
2666 		inet6_rthdr_lasthop(cmsg, IPV6_RTHDR_LOOSE);
2667 		len = cmsg->cmsg_len;
2668 		*cpp = rhbuf;
2669 	}
2670 #endif
2671 	else
2672 		return -1;
2673 	return len;
2674 }
2675 #endif
2676