xref: /openbsd-src/usr.bin/telnet/commands.c (revision 50b7afb2c2c0993b0894d4e34bf857cb13ed9c80)
1 /*	$OpenBSD: commands.c,v 1.56 2014/07/19 23:50:38 guenther Exp $	*/
2 /*	$NetBSD: commands.c,v 1.14 1996/03/24 22:03:48 jtk Exp $	*/
3 
4 /*
5  * Copyright (c) 1988, 1990, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include "telnet_locl.h"
34 #include <err.h>
35 
36 int tos = -1;
37 
38 char	*hostname;
39 
40 typedef int (*intrtn_t)(int, char**);
41 static int call(intrtn_t, ...);
42 
43 typedef struct {
44 	char	*name;		/* command name */
45 	char	*help;		/* help string (NULL for no help) */
46 	int	(*handler)();	/* routine which executes command */
47 	int	needconnect;	/* Do we need to be connected to execute? */
48 } Command;
49 
50 static char line[256];
51 static char saveline[256];
52 static int margc;
53 static char *margv[20];
54 
55 #if	defined(SKEY)
56 #include <sys/wait.h>
57 #define PATH_SKEY	"/usr/bin/skey"
58     int
59 skey_calc(argc, argv)
60 	int argc;
61 	char **argv;
62 {
63 	int status;
64 
65 	if(argc != 3) {
66 		printf("usage: %s sequence challenge\n", argv[0]);
67 		return 0;
68 	}
69 
70 	switch(fork()) {
71 	case 0:
72 		execv(PATH_SKEY, argv);
73 		exit (1);
74 	case -1:
75 		err(1, "fork");
76 		break;
77 	default:
78 		(void) wait(&status);
79 		if (WIFEXITED(status))
80 			return (WEXITSTATUS(status));
81 		return (0);
82 	}
83 }
84 #endif
85 
86 
87 
88     static void
89 makeargv()
90 {
91     char *cp, *cp2, c;
92     char **argp = margv;
93 
94     margc = 0;
95     cp = line;
96     if (*cp == '!') {		/* Special case shell escape */
97 	strlcpy(saveline, line, sizeof(saveline)); /* save for shell command */
98 	*argp++ = "!";		/* No room in string to get this */
99 	margc++;
100 	cp++;
101     }
102     while ((c = *cp)) {
103 	int inquote = 0;
104 	while (isspace(c))
105 	    c = *++cp;
106 	if (c == '\0')
107 	    break;
108 	*argp++ = cp;
109 	margc += 1;
110 	for (cp2 = cp; c != '\0'; c = *++cp) {
111 	    if (inquote) {
112 		if (c == inquote) {
113 		    inquote = 0;
114 		    continue;
115 		}
116 	    } else {
117 		if (c == '\\') {
118 		    if ((c = *++cp) == '\0')
119 			break;
120 		} else if (c == '"') {
121 		    inquote = '"';
122 		    continue;
123 		} else if (c == '\'') {
124 		    inquote = '\'';
125 		    continue;
126 		} else if (isspace(c))
127 		    break;
128 	    }
129 	    *cp2++ = c;
130 	}
131 	*cp2 = '\0';
132 	if (c == '\0')
133 	    break;
134 	cp++;
135     }
136     *argp++ = 0;
137 }
138 
139 /*
140  * Make a character string into a number.
141  *
142  * Todo:  1.  Could take random integers (12, 0x12, 012, 0b1).
143  */
144 
145 	static char
146 special(s)
147 	char *s;
148 {
149 	char c;
150 	char b;
151 
152 	switch (*s) {
153 	case '^':
154 		b = *++s;
155 		if (b == '?') {
156 		    c = b | 0x40;		/* DEL */
157 		} else {
158 		    c = b & 0x1f;
159 		}
160 		break;
161 	default:
162 		c = *s;
163 		break;
164 	}
165 	return c;
166 }
167 
168 /*
169  * Construct a control character sequence
170  * for a special character.
171  */
172 	static char *
173 control(c)
174 	cc_t c;
175 {
176 	static char buf[5];
177 	/*
178 	 * The only way I could get the Sun 3.5 compiler
179 	 * to shut up about
180 	 *	if ((unsigned int)c >= 0x80)
181 	 * was to assign "c" to an unsigned int variable...
182 	 * Arggg....
183 	 */
184 	unsigned int uic = (unsigned int)c;
185 
186 	if (uic == 0x7f)
187 		return ("^?");
188 	if (c == (cc_t)_POSIX_VDISABLE) {
189 		return "off";
190 	}
191 	if (uic >= 0x80) {
192 		buf[0] = '\\';
193 		buf[1] = ((c>>6)&07) + '0';
194 		buf[2] = ((c>>3)&07) + '0';
195 		buf[3] = (c&07) + '0';
196 		buf[4] = 0;
197 	} else if (uic >= 0x20) {
198 		buf[0] = c;
199 		buf[1] = 0;
200 	} else {
201 		buf[0] = '^';
202 		buf[1] = '@'+c;
203 		buf[2] = 0;
204 	}
205 	return (buf);
206 }
207 
208 
209 
210 /*
211  *	The following are data structures and routines for
212  *	the "send" command.
213  *
214  */
215 
216 struct sendlist {
217     char	*name;		/* How user refers to it (case independent) */
218     char	*help;		/* Help information (0 ==> no help) */
219     int		needconnect;	/* Need to be connected */
220     int		narg;		/* Number of arguments */
221     int		(*handler)();	/* Routine to perform (for special ops) */
222     int		nbyte;		/* Number of bytes to send this command */
223     int		what;		/* Character to be sent (<0 ==> special) */
224 };
225 
226 
227 static int
228 	send_esc(void),
229 	send_help(void),
230 	send_docmd(char *),
231 	send_dontcmd(char *),
232 	send_willcmd(char *),
233 	send_wontcmd(char *);
234 
235 static struct sendlist Sendlist[] = {
236     { "ao",	"Send Telnet Abort output",		1, 0, 0, 2, AO },
237     { "ayt",	"Send Telnet 'Are You There'",		1, 0, 0, 2, AYT },
238     { "brk",	"Send Telnet Break",			1, 0, 0, 2, BREAK },
239     { "break",	0,					1, 0, 0, 2, BREAK },
240     { "ec",	"Send Telnet Erase Character",		1, 0, 0, 2, EC },
241     { "el",	"Send Telnet Erase Line",		1, 0, 0, 2, EL },
242     { "escape",	"Send current escape character",	1, 0, send_esc, 1, 0 },
243     { "ga",	"Send Telnet 'Go Ahead' sequence",	1, 0, 0, 2, GA },
244     { "ip",	"Send Telnet Interrupt Process",	1, 0, 0, 2, IP },
245     { "intp",	0,					1, 0, 0, 2, IP },
246     { "interrupt", 0,					1, 0, 0, 2, IP },
247     { "intr",	0,					1, 0, 0, 2, IP },
248     { "nop",	"Send Telnet 'No operation'",		1, 0, 0, 2, NOP },
249     { "eor",	"Send Telnet 'End of Record'",		1, 0, 0, 2, EOR },
250     { "abort",	"Send Telnet 'Abort Process'",		1, 0, 0, 2, ABORT },
251     { "susp",	"Send Telnet 'Suspend Process'",	1, 0, 0, 2, SUSP },
252     { "eof",	"Send Telnet End of File Character",	1, 0, 0, 2, xEOF },
253     { "synch",	"Perform Telnet 'Synch operation'",	1, 0, dosynch, 2, 0 },
254     { "getstatus", "Send request for STATUS",		1, 0, get_status, 6, 0 },
255     { "?",	"Display send options",			0, 0, send_help, 0, 0 },
256     { "help",	0,					0, 0, send_help, 0, 0 },
257     { "do",	0,					0, 1, send_docmd, 3, 0 },
258     { "dont",	0,					0, 1, send_dontcmd, 3, 0 },
259     { "will",	0,					0, 1, send_willcmd, 3, 0 },
260     { "wont",	0,					0, 1, send_wontcmd, 3, 0 },
261     { 0 }
262 };
263 
264 #define	GETSEND(name) ((struct sendlist *) genget(name, (char **) Sendlist, \
265 				sizeof(struct sendlist)))
266 
267     static int
268 sendcmd(argc, argv)
269     int  argc;
270     char **argv;
271 {
272     int count;		/* how many bytes we are going to need to send */
273     int i;
274     struct sendlist *s;	/* pointer to current command */
275     int success = 0;
276     int needconnect = 0;
277 
278     if (argc < 2) {
279 	printf("need at least one argument for 'send' command\r\n");
280 	printf("'send ?' for help\r\n");
281 	return 0;
282     }
283     /*
284      * First, validate all the send arguments.
285      * In addition, we see how much space we are going to need, and
286      * whether or not we will be doing a "SYNCH" operation (which
287      * flushes the network queue).
288      */
289     count = 0;
290     for (i = 1; i < argc; i++) {
291 	s = GETSEND(argv[i]);
292 	if (s == 0) {
293 	    printf("Unknown send argument '%s'\r\n'send ?' for help.\r\n",
294 			argv[i]);
295 	    return 0;
296 	} else if (Ambiguous(s)) {
297 	    printf("Ambiguous send argument '%s'\r\n'send ?' for help.\r\n",
298 			argv[i]);
299 	    return 0;
300 	}
301 	if (i + s->narg >= argc) {
302 	    fprintf(stderr,
303 	    "Need %d argument%s to 'send %s' command.  'send %s ?' for help.\r\n",
304 		s->narg, s->narg == 1 ? "" : "s", s->name, s->name);
305 	    return 0;
306 	}
307 	count += s->nbyte;
308 	if (s->handler == send_help) {
309 	    send_help();
310 	    return 0;
311 	}
312 
313 	i += s->narg;
314 	needconnect += s->needconnect;
315     }
316     if (!connected && needconnect) {
317 	printf("?Need to be connected first.\r\n");
318 	printf("'send ?' for help\r\n");
319 	return 0;
320     }
321     /* Now, do we have enough room? */
322     if (NETROOM() < count) {
323 	printf("There is not enough room in the buffer TO the network\r\n");
324 	printf("to process your request.  Nothing will be done.\r\n");
325 	printf("('send synch' will throw away most data in the network\r\n");
326 	printf("buffer, if this might help.)\r\n");
327 	return 0;
328     }
329     /* OK, they are all OK, now go through again and actually send */
330     count = 0;
331     for (i = 1; i < argc; i++) {
332 	if ((s = GETSEND(argv[i])) == 0) {
333 	    fprintf(stderr, "Telnet 'send' error - argument disappeared!\r\n");
334 	    (void) quit();
335 	    /*NOTREACHED*/
336 	}
337 	if (s->handler) {
338 	    count++;
339 	    success += (*s->handler)((s->narg > 0) ? argv[i+1] : 0,
340 				  (s->narg > 1) ? argv[i+2] : 0);
341 	    i += s->narg;
342 	} else {
343 	    NET2ADD(IAC, s->what);
344 	    printoption("SENT", IAC, s->what);
345 	}
346     }
347     return (count == success);
348 }
349 
350 	static int
351 send_tncmd(void (*func)(), char *cmd, char *name);
352 
353     static int
354 send_esc()
355 {
356     NETADD(escape);
357     return 1;
358 }
359 
360     static int
361 send_docmd(name)
362     char *name;
363 {
364     return(send_tncmd(send_do, "do", name));
365 }
366 
367     static int
368 send_dontcmd(name)
369     char *name;
370 {
371     return(send_tncmd(send_dont, "dont", name));
372 }
373     static int
374 send_willcmd(name)
375     char *name;
376 {
377     return(send_tncmd(send_will, "will", name));
378 }
379     static int
380 send_wontcmd(name)
381     char *name;
382 {
383     return(send_tncmd(send_wont, "wont", name));
384 }
385 
386     int
387 send_tncmd(func, cmd, name)
388     void	(*func)();
389     char	*cmd, *name;
390 {
391     char **cpp;
392     extern char *telopts[];
393     int val = 0;
394 
395     if (isprefix(name, "help") || isprefix(name, "?")) {
396 	int col, len;
397 
398 	printf("Usage: send %s <value|option>\r\n", cmd);
399 	printf("\"value\" must be from 0 to 255\r\n");
400 	printf("Valid options are:\r\n\t");
401 
402 	col = 8;
403 	for (cpp = telopts; *cpp; cpp++) {
404 	    len = strlen(*cpp) + 3;
405 	    if (col + len > 65) {
406 		printf("\r\n\t");
407 		col = 8;
408 	    }
409 	    printf(" \"%s\"", *cpp);
410 	    col += len;
411 	}
412 	printf("\r\n");
413 	return 0;
414     }
415     cpp = (char **)genget(name, telopts, sizeof(char *));
416     if (Ambiguous(cpp)) {
417 	fprintf(stderr,"'%s': ambiguous argument ('send %s ?' for help).\r\n",
418 					name, cmd);
419 	return 0;
420     }
421     if (cpp) {
422 	val = cpp - telopts;
423     } else {
424 	char *cp = name;
425 
426 	while (*cp >= '0' && *cp <= '9') {
427 	    val *= 10;
428 	    val += *cp - '0';
429 	    cp++;
430 	}
431 	if (*cp != 0) {
432 	    fprintf(stderr, "'%s': unknown argument ('send %s ?' for help).\r\n",
433 					name, cmd);
434 	    return 0;
435 	} else if (val < 0 || val > 255) {
436 	    fprintf(stderr, "'%s': bad value ('send %s ?' for help).\r\n",
437 					name, cmd);
438 	    return 0;
439 	}
440     }
441     if (!connected) {
442 	printf("?Need to be connected first.\r\n");
443 	return 0;
444     }
445     (*func)(val, 1);
446     return 1;
447 }
448 
449     static int
450 send_help()
451 {
452     struct sendlist *s;	/* pointer to current command */
453     for (s = Sendlist; s->name; s++) {
454 	if (s->help)
455 	    printf("%-15s %s\r\n", s->name, s->help);
456     }
457     return(0);
458 }
459 
460 /*
461  * The following are the routines and data structures referred
462  * to by the arguments to the "toggle" command.
463  */
464 
465     static int
466 lclchars()
467 {
468     donelclchars = 1;
469     return 1;
470 }
471 
472     static int
473 togdebug()
474 {
475     if (net > 0 &&
476 	(setsockopt(net, SOL_SOCKET, SO_DEBUG, &debug, sizeof(debug))) == -1) {
477 	    perror("setsockopt (SO_DEBUG)");
478     }
479     return 1;
480 }
481 
482 
483     static int
484 togcrlf()
485 {
486     if (crlf) {
487 	printf("Will send carriage returns as telnet <CR><LF>.\r\n");
488     } else {
489 	printf("Will send carriage returns as telnet <CR><NUL>.\r\n");
490     }
491     return 1;
492 }
493 
494 int binmode;
495 
496     static int
497 togbinary(val)
498     int val;
499 {
500     donebinarytoggle = 1;
501 
502     if (val >= 0) {
503 	binmode = val;
504     } else {
505 	if (my_want_state_is_will(TELOPT_BINARY) &&
506 				my_want_state_is_do(TELOPT_BINARY)) {
507 	    binmode = 1;
508 	} else if (my_want_state_is_wont(TELOPT_BINARY) &&
509 				my_want_state_is_dont(TELOPT_BINARY)) {
510 	    binmode = 0;
511 	}
512 	val = binmode ? 0 : 1;
513     }
514 
515     if (val == 1) {
516 	if (my_want_state_is_will(TELOPT_BINARY) &&
517 					my_want_state_is_do(TELOPT_BINARY)) {
518 	    printf("Already operating in binary mode with remote host.\r\n");
519 	} else {
520 	    printf("Negotiating binary mode with remote host.\r\n");
521 	    tel_enter_binary(3);
522 	}
523     } else {
524 	if (my_want_state_is_wont(TELOPT_BINARY) &&
525 					my_want_state_is_dont(TELOPT_BINARY)) {
526 	    printf("Already in network ascii mode with remote host.\r\n");
527 	} else {
528 	    printf("Negotiating network ascii mode with remote host.\r\n");
529 	    tel_leave_binary(3);
530 	}
531     }
532     return 1;
533 }
534 
535     static int
536 togrbinary(val)
537     int val;
538 {
539     donebinarytoggle = 1;
540 
541     if (val == -1)
542 	val = my_want_state_is_do(TELOPT_BINARY) ? 0 : 1;
543 
544     if (val == 1) {
545 	if (my_want_state_is_do(TELOPT_BINARY)) {
546 	    printf("Already receiving in binary mode.\r\n");
547 	} else {
548 	    printf("Negotiating binary mode on input.\r\n");
549 	    tel_enter_binary(1);
550 	}
551     } else {
552 	if (my_want_state_is_dont(TELOPT_BINARY)) {
553 	    printf("Already receiving in network ascii mode.\r\n");
554 	} else {
555 	    printf("Negotiating network ascii mode on input.\r\n");
556 	    tel_leave_binary(1);
557 	}
558     }
559     return 1;
560 }
561 
562     static int
563 togxbinary(val)
564     int val;
565 {
566     donebinarytoggle = 1;
567 
568     if (val == -1)
569 	val = my_want_state_is_will(TELOPT_BINARY) ? 0 : 1;
570 
571     if (val == 1) {
572 	if (my_want_state_is_will(TELOPT_BINARY)) {
573 	    printf("Already transmitting in binary mode.\r\n");
574 	} else {
575 	    printf("Negotiating binary mode on output.\r\n");
576 	    tel_enter_binary(2);
577 	}
578     } else {
579 	if (my_want_state_is_wont(TELOPT_BINARY)) {
580 	    printf("Already transmitting in network ascii mode.\r\n");
581 	} else {
582 	    printf("Negotiating network ascii mode on output.\r\n");
583 	    tel_leave_binary(2);
584 	}
585     }
586     return 1;
587 }
588 
589 
590 static int togglehelp(void);
591 
592 struct togglelist {
593     char	*name;		/* name of toggle */
594     char	*help;		/* help message */
595     int		(*handler)();	/* routine to do actual setting */
596     int		*variable;
597     char	*actionexplanation;
598     int		needconnect;	/* Need to be connected */
599 };
600 
601 static struct togglelist Togglelist[] = {
602     { "autoflush",
603 	"flushing of output when sending interrupt characters",
604 	    0,
605 		&autoflush,
606 		    "flush output when sending interrupt characters" },
607     { "autosynch",
608 	"automatic sending of interrupt characters in urgent mode",
609 	    0,
610 		&autosynch,
611 		    "send interrupt characters in urgent mode" },
612     { "autologin",
613 	"automatic sending of login and/or authentication info",
614 	    0,
615 		&autologin,
616 		    "send login name and/or authentication information" },
617     { "skiprc",
618 	"don't read ~/.telnetrc file",
619 	    0,
620 		&skiprc,
621 		    "skip reading of ~/.telnetrc file" },
622     { "binary",
623 	"sending and receiving of binary data",
624 	    togbinary,
625 		0,
626 		    0 },
627     { "inbinary",
628 	"receiving of binary data",
629 	    togrbinary,
630 		0,
631 		    0 },
632     { "outbinary",
633 	"sending of binary data",
634 	    togxbinary,
635 		0,
636 		    0 },
637     { "crlf",
638 	"sending carriage returns as telnet <CR><LF>",
639 	    togcrlf,
640 		&crlf,
641 		    0 },
642     { "crmod",
643 	"mapping of received carriage returns",
644 	    0,
645 		&crmod,
646 		    "map carriage return on output" },
647     { "localchars",
648 	"local recognition of certain control characters",
649 	    lclchars,
650 		&localchars,
651 		    "recognize certain control characters" },
652     { " ", "", 0, 0 },		/* empty line */
653     { "debug",
654 	"debugging",
655 	    togdebug,
656 		&debug,
657 		    "turn on socket level debugging" },
658     { "netdata",
659 	"printing of hexadecimal network data (debugging)",
660 	    0,
661 		&netdata,
662 		    "print hexadecimal representation of network traffic" },
663     { "prettydump",
664 	"output of \"netdata\" to user readable format (debugging)",
665 	    0,
666 		&prettydump,
667 		    "print user readable output for \"netdata\"" },
668     { "options",
669 	"viewing of options processing (debugging)",
670 	    0,
671 		&showoptions,
672 		    "show option processing" },
673     { "termdata",
674 	"(debugging) toggle printing of hexadecimal terminal data",
675 	    0,
676 		&termdata,
677 		    "print hexadecimal representation of terminal traffic" },
678     { "?",
679 	0,
680 	    togglehelp },
681     { "help",
682 	0,
683 	    togglehelp },
684     { 0 }
685 };
686 
687     static int
688 togglehelp()
689 {
690     struct togglelist *c;
691 
692     for (c = Togglelist; c->name; c++) {
693 	if (c->help) {
694 	    if (*c->help)
695 		printf("%-15s toggle %s\r\n", c->name, c->help);
696 	    else
697 		printf("\r\n");
698 	}
699     }
700     printf("\r\n");
701     printf("%-15s %s\r\n", "?", "display help information");
702     return 0;
703 }
704 
705     static void
706 settogglehelp(set)
707     int set;
708 {
709     struct togglelist *c;
710 
711     for (c = Togglelist; c->name; c++) {
712 	if (c->help) {
713 	    if (*c->help)
714 		printf("%-15s %s %s\r\n", c->name, set ? "enable" : "disable",
715 						c->help);
716 	    else
717 		printf("\r\n");
718 	}
719     }
720 }
721 
722 #define	GETTOGGLE(name) (struct togglelist *) \
723 		genget(name, (char **) Togglelist, sizeof(struct togglelist))
724 
725     static int
726 toggle(argc, argv)
727     int  argc;
728     char *argv[];
729 {
730     int retval = 1;
731     char *name;
732     struct togglelist *c;
733 
734     if (argc < 2) {
735 	fprintf(stderr,
736 	    "Need an argument to 'toggle' command.  'toggle ?' for help.\r\n");
737 	return 0;
738     }
739     argc--;
740     argv++;
741     while (argc--) {
742 	name = *argv++;
743 	c = GETTOGGLE(name);
744 	if (Ambiguous(c)) {
745 	    fprintf(stderr, "'%s': ambiguous argument ('toggle ?' for help).\r\n",
746 					name);
747 	    return 0;
748 	} else if (c == 0) {
749 	    fprintf(stderr, "'%s': unknown argument ('toggle ?' for help).\r\n",
750 					name);
751 	    return 0;
752 	} else if (!connected && c->needconnect) {
753 	    printf("?Need to be connected first.\r\n");
754 	    printf("'send ?' for help\r\n");
755 	    return 0;
756 	} else {
757 	    if (c->variable) {
758 		*c->variable = !*c->variable;		/* invert it */
759 		if (c->actionexplanation) {
760 		    printf("%s %s.\r\n", *c->variable? "Will" : "Won't",
761 							c->actionexplanation);
762 		}
763 	    }
764 	    if (c->handler) {
765 		retval &= (*c->handler)(-1);
766 	    }
767 	}
768     }
769     return retval;
770 }
771 
772 /*
773  * The following perform the "set" command.
774  */
775 
776 struct termios new_tc = { 0 };
777 
778 struct setlist {
779     char *name;				/* name */
780     char *help;				/* help information */
781     void (*handler)();
782     cc_t *charp;			/* where it is located at */
783 };
784 
785 static struct setlist Setlist[] = {
786 #ifdef	KLUDGELINEMODE
787     { "echo", 	"character to toggle local echoing on/off", 0, &echoc },
788 #endif
789     { "escape",	"character to escape back to telnet command mode", 0, &escape },
790     { "rlogin", "rlogin escape character", 0, &rlogin },
791     { "tracefile", "file to write trace information to", SetNetTrace, (cc_t *)NetTraceFile},
792     { " ", "" },
793     { " ", "The following need 'localchars' to be toggled true", 0, 0 },
794     { "flushoutput", "character to cause an Abort Output", 0, &termFlushChar },
795     { "interrupt", "character to cause an Interrupt Process", 0, &termIntChar },
796     { "quit",	"character to cause an Abort process", 0, &termQuitChar },
797     { "eof",	"character to cause an EOF ", 0, &termEofChar },
798     { " ", "" },
799     { " ", "The following are for local editing in linemode", 0, 0 },
800     { "erase",	"character to use to erase a character", 0, &termEraseChar },
801     { "kill",	"character to use to erase a line", 0, &termKillChar },
802     { "lnext",	"character to use for literal next", 0, &termLiteralNextChar },
803     { "susp",	"character to cause a Suspend Process", 0, &termSuspChar },
804     { "reprint", "character to use for line reprint", 0, &termRprntChar },
805     { "worderase", "character to use to erase a word", 0, &termWerasChar },
806     { "start",	"character to use for XON", 0, &termStartChar },
807     { "stop",	"character to use for XOFF", 0, &termStopChar },
808     { "forw1",	"alternate end of line character", 0, &termForw1Char },
809     { "forw2",	"alternate end of line character", 0, &termForw2Char },
810     { "ayt",	"alternate AYT character", 0, &termAytChar },
811     { 0 }
812 };
813 
814     static struct setlist *
815 getset(name)
816     char *name;
817 {
818     return (struct setlist *)
819 		genget(name, (char **) Setlist, sizeof(struct setlist));
820 }
821 
822     void
823 set_escape_char(s)
824     char *s;
825 {
826 	if (rlogin != _POSIX_VDISABLE) {
827 		rlogin = (s && *s) ? special(s) : _POSIX_VDISABLE;
828 		printf("Telnet rlogin escape character is '%s'.\r\n",
829 					control(rlogin));
830 	} else {
831 		escape = (s && *s) ? special(s) : _POSIX_VDISABLE;
832 		printf("Telnet escape character is '%s'.\r\n", control(escape));
833 	}
834 }
835 
836     static int
837 setcmd(argc, argv)
838     int  argc;
839     char *argv[];
840 {
841     int value;
842     struct setlist *ct;
843     struct togglelist *c;
844 
845     if (argc < 2 || argc > 3) {
846 	printf("Format is 'set Name Value'\r\n'set ?' for help.\r\n");
847 	return 0;
848     }
849     if ((argc == 2) && (isprefix(argv[1], "?") || isprefix(argv[1], "help"))) {
850 	for (ct = Setlist; ct->name; ct++)
851 	    printf("%-15s %s\r\n", ct->name, ct->help);
852 	printf("\r\n");
853 	settogglehelp(1);
854 	printf("%-15s %s\r\n", "?", "display help information");
855 	return 0;
856     }
857 
858     ct = getset(argv[1]);
859     if (ct == 0) {
860 	c = GETTOGGLE(argv[1]);
861 	if (c == 0) {
862 	    fprintf(stderr, "'%s': unknown argument ('set ?' for help).\r\n",
863 			argv[1]);
864 	    return 0;
865 	} else if (Ambiguous(c)) {
866 	    fprintf(stderr, "'%s': ambiguous argument ('set ?' for help).\r\n",
867 			argv[1]);
868 	    return 0;
869 	} else if (!connected && c->needconnect) {
870 	    printf("?Need to be connected first.\r\n");
871 	    printf("'send ?' for help\r\n");
872 	    return 0;
873 	}
874 
875 	if (c->variable) {
876 	    if ((argc == 2) || (strcmp("on", argv[2]) == 0))
877 		*c->variable = 1;
878 	    else if (strcmp("off", argv[2]) == 0)
879 		*c->variable = 0;
880 	    else {
881 		printf("Format is 'set togglename [on|off]'\r\n'set ?' for help.\r\n");
882 		return 0;
883 	    }
884 	    if (c->actionexplanation) {
885 		printf("%s %s.\r\n", *c->variable? "Will" : "Won't",
886 							c->actionexplanation);
887 	    }
888 	}
889 	if (c->handler)
890 	    (*c->handler)(1);
891     } else if (argc != 3) {
892 	printf("Format is 'set Name Value'\r\n'set ?' for help.\r\n");
893 	return 0;
894     } else if (Ambiguous(ct)) {
895 	fprintf(stderr, "'%s': ambiguous argument ('set ?' for help).\r\n",
896 			argv[1]);
897 	return 0;
898     } else if (ct->handler) {
899 	(*ct->handler)(argv[2]);
900 	printf("%s set to \"%s\".\r\n", ct->name, (char *)ct->charp);
901     } else {
902 	if (strcmp("off", argv[2])) {
903 	    value = special(argv[2]);
904 	} else {
905 	    value = _POSIX_VDISABLE;
906 	}
907 	*(ct->charp) = (cc_t)value;
908 	printf("%s character is '%s'.\r\n", ct->name, control(*(ct->charp)));
909     }
910     slc_check();
911     return 1;
912 }
913 
914     static int
915 unsetcmd(argc, argv)
916     int  argc;
917     char *argv[];
918 {
919     struct setlist *ct;
920     struct togglelist *c;
921     char *name;
922 
923     if (argc < 2) {
924 	fprintf(stderr,
925 	    "Need an argument to 'unset' command.  'unset ?' for help.\r\n");
926 	return 0;
927     }
928     if (isprefix(argv[1], "?") || isprefix(argv[1], "help")) {
929 	for (ct = Setlist; ct->name; ct++)
930 	    printf("%-15s %s\r\n", ct->name, ct->help);
931 	printf("\r\n");
932 	settogglehelp(0);
933 	printf("%-15s %s\r\n", "?", "display help information");
934 	return 0;
935     }
936 
937     argc--;
938     argv++;
939     while (argc--) {
940 	name = *argv++;
941 	ct = getset(name);
942 	if (ct == 0) {
943 	    c = GETTOGGLE(name);
944 	    if (c == 0) {
945 		fprintf(stderr, "'%s': unknown argument ('unset ?' for help).\r\n",
946 			name);
947 		return 0;
948 	    } else if (Ambiguous(c)) {
949 		fprintf(stderr, "'%s': ambiguous argument ('unset ?' for help).\r\n",
950 			name);
951 		return 0;
952 	    }
953 	    if (c->variable) {
954 		*c->variable = 0;
955 		if (c->actionexplanation) {
956 		    printf("%s %s.\r\n", *c->variable? "Will" : "Won't",
957 							c->actionexplanation);
958 		}
959 	    }
960 	    if (c->handler)
961 		(*c->handler)(0);
962 	} else if (Ambiguous(ct)) {
963 	    fprintf(stderr, "'%s': ambiguous argument ('unset ?' for help).\r\n",
964 			name);
965 	    return 0;
966 	} else if (ct->handler) {
967 	    (*ct->handler)(0);
968 	    printf("%s reset to \"%s\".\r\n", ct->name, (char *)ct->charp);
969 	} else {
970 	    *(ct->charp) = _POSIX_VDISABLE;
971 	    printf("%s character is '%s'.\r\n", ct->name, control(*(ct->charp)));
972 	}
973     }
974     return 1;
975 }
976 
977 /*
978  * The following are the data structures and routines for the
979  * 'mode' command.
980  */
981 #ifdef	KLUDGELINEMODE
982 extern int kludgelinemode;
983 
984     static int
985 dokludgemode()
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(bit, on)
1022     int bit, on;
1023 {
1024     unsigned char c;
1025     extern int linemode;
1026 
1027     if (my_want_state_is_wont(TELOPT_LINEMODE)) {
1028 	printf("?Need to have LINEMODE option enabled first.\r\n");
1029 	printf("'mode ?' for help.\r\n");
1030 	return 0;
1031     }
1032 
1033     if (on)
1034 	c = (linemode | bit);
1035     else
1036 	c = (linemode & ~bit);
1037     lm_mode(&c, 1, 1);
1038     return 1;
1039 }
1040 
1041     int
1042 tn_setmode(bit)
1043 {
1044     return dolmmode(bit, 1);
1045 }
1046 
1047     int
1048 tn_clearmode(bit)
1049 {
1050     return dolmmode(bit, 0);
1051 }
1052 
1053 struct modelist {
1054 	char	*name;		/* command name */
1055 	char	*help;		/* help string */
1056 	int	(*handler)();	/* routine which executes command */
1057 	int	needconnect;	/* Do we need to be connected to execute? */
1058 	int	arg1;
1059 };
1060 
1061 static int modehelp(void);
1062 
1063 static struct modelist ModeList[] = {
1064     { "character", "Disable LINEMODE option",	docharmode, 1 },
1065 #ifdef	KLUDGELINEMODE
1066     { "",	"(or disable obsolete line-by-line mode)", 0 },
1067 #endif
1068     { "line",	"Enable LINEMODE option",	dolinemode, 1 },
1069 #ifdef	KLUDGELINEMODE
1070     { "",	"(or enable obsolete line-by-line mode)", 0 },
1071 #endif
1072     { "", "", 0 },
1073     { "",	"These require the LINEMODE option to be enabled", 0 },
1074     { "isig",	"Enable signal trapping",	tn_setmode, 1, MODE_TRAPSIG },
1075     { "+isig",	0,				tn_setmode, 1, MODE_TRAPSIG },
1076     { "-isig",	"Disable signal trapping",	tn_clearmode, 1, MODE_TRAPSIG },
1077     { "edit",	"Enable character editing",	tn_setmode, 1, MODE_EDIT },
1078     { "+edit",	0,				tn_setmode, 1, MODE_EDIT },
1079     { "-edit",	"Disable character editing",	tn_clearmode, 1, MODE_EDIT },
1080     { "softtabs", "Enable tab expansion",	tn_setmode, 1, MODE_SOFT_TAB },
1081     { "+softtabs", 0,				tn_setmode, 1, MODE_SOFT_TAB },
1082     { "-softtabs", "Disable character editing",	tn_clearmode, 1, MODE_SOFT_TAB },
1083     { "litecho", "Enable literal character echo", tn_setmode, 1, MODE_LIT_ECHO },
1084     { "+litecho", 0,				tn_setmode, 1, MODE_LIT_ECHO },
1085     { "-litecho", "Disable literal character echo", tn_clearmode, 1, MODE_LIT_ECHO },
1086     { "help",	0,				modehelp, 0 },
1087 #ifdef	KLUDGELINEMODE
1088     { "kludgeline", 0,				dokludgemode, 1 },
1089 #endif
1090     { "", "", 0 },
1091     { "?",	"Print help information",	modehelp, 0 },
1092     { 0 },
1093 };
1094 
1095 
1096     static int
1097 modehelp()
1098 {
1099     struct modelist *mt;
1100 
1101     printf("format is:  'mode Mode', where 'Mode' is one of:\r\n\r\n");
1102     for (mt = ModeList; mt->name; mt++) {
1103 	if (mt->help) {
1104 	    if (*mt->help)
1105 		printf("%-15s %s\r\n", mt->name, mt->help);
1106 	    else
1107 		printf("\r\n");
1108 	}
1109     }
1110     return 0;
1111 }
1112 
1113 #define	GETMODECMD(name) (struct modelist *) \
1114 		genget(name, (char **) ModeList, sizeof(struct modelist))
1115 
1116     static int
1117 modecmd(argc, argv)
1118     int  argc;
1119     char *argv[];
1120 {
1121     struct modelist *mt;
1122 
1123     if (argc != 2) {
1124 	printf("'mode' command requires an argument\r\n");
1125 	printf("'mode ?' for help.\r\n");
1126     } else if ((mt = GETMODECMD(argv[1])) == 0) {
1127 	fprintf(stderr, "Unknown mode '%s' ('mode ?' for help).\r\n", argv[1]);
1128     } else if (Ambiguous(mt)) {
1129 	fprintf(stderr, "Ambiguous mode '%s' ('mode ?' for help).\r\n", argv[1]);
1130     } else if (mt->needconnect && !connected) {
1131 	printf("?Need to be connected first.\r\n");
1132 	printf("'mode ?' for help.\r\n");
1133     } else if (mt->handler) {
1134 	return (*mt->handler)(mt->arg1);
1135     }
1136     return 0;
1137 }
1138 
1139 /*
1140  * The following data structures and routines implement the
1141  * "display" command.
1142  */
1143 
1144     static int
1145 display(argc, argv)
1146     int  argc;
1147     char *argv[];
1148 {
1149     struct togglelist *tl;
1150     struct setlist *sl;
1151 
1152 #define	dotog(tl)	if (tl->variable && tl->actionexplanation) { \
1153 			    if (*tl->variable) { \
1154 				printf("will"); \
1155 			    } else { \
1156 				printf("won't"); \
1157 			    } \
1158 			    printf(" %s.\r\n", tl->actionexplanation); \
1159 			}
1160 
1161 #define	doset(sl)   if (sl->name && *sl->name != ' ') { \
1162 			if (sl->handler == 0) \
1163 			    printf("%-15s [%s]\r\n", sl->name, control(*sl->charp)); \
1164 			else \
1165 			    printf("%-15s \"%s\"\r\n", sl->name, (char *)sl->charp); \
1166 		    }
1167 
1168     if (argc == 1) {
1169 	for (tl = Togglelist; tl->name; tl++) {
1170 	    dotog(tl);
1171 	}
1172 	printf("\r\n");
1173 	for (sl = Setlist; sl->name; sl++) {
1174 	    doset(sl);
1175 	}
1176     } else {
1177 	int i;
1178 
1179 	for (i = 1; i < argc; i++) {
1180 	    sl = getset(argv[i]);
1181 	    tl = GETTOGGLE(argv[i]);
1182 	    if (Ambiguous(sl) || Ambiguous(tl)) {
1183 		printf("?Ambiguous argument '%s'.\r\n", argv[i]);
1184 		return 0;
1185 	    } else if (!sl && !tl) {
1186 		printf("?Unknown argument '%s'.\r\n", argv[i]);
1187 		return 0;
1188 	    } else {
1189 		if (tl) {
1190 		    dotog(tl);
1191 		}
1192 		if (sl) {
1193 		    doset(sl);
1194 		}
1195 	    }
1196 	}
1197     }
1198 /*@*/optionstatus();
1199     return 1;
1200 #undef	doset
1201 #undef	dotog
1202 }
1203 
1204 /*
1205  * The following are the data structures, and many of the routines,
1206  * relating to command processing.
1207  */
1208 
1209 /*
1210  * Set the escape character.
1211  */
1212 	static int
1213 setescape(argc, argv)
1214 	int argc;
1215 	char *argv[];
1216 {
1217 	char *arg;
1218 	char buf[50];
1219 
1220 	printf(
1221 	    "Deprecated usage - please use 'set escape%s%s' in the future.\r\n",
1222 				(argc > 2)? " ":"", (argc > 2)? argv[1]: "");
1223 	if (argc > 2)
1224 		arg = argv[1];
1225 	else {
1226 		printf("new escape character: ");
1227 		(void) fgets(buf, sizeof(buf), stdin);
1228 		arg = buf;
1229 	}
1230 	if (arg[0] != '\0')
1231 		escape = arg[0];
1232 	printf("Escape character is '%s'.\r\n", control(escape));
1233 	(void) fflush(stdout);
1234 	return 1;
1235 }
1236 
1237     /*VARARGS*/
1238     static int
1239 togcrmod()
1240 {
1241     crmod = !crmod;
1242     printf("Deprecated usage - please use 'toggle crmod' in the future.\r\n");
1243     printf("%s map carriage return on output.\r\n", crmod ? "Will" : "Won't");
1244     (void) fflush(stdout);
1245     return 1;
1246 }
1247 
1248     /*VARARGS*/
1249     int
1250 telnetsuspend()
1251 {
1252 #ifdef	SIGTSTP
1253     setcommandmode();
1254     {
1255 	long oldrows, oldcols, newrows, newcols, err;
1256 
1257 	err = (TerminalWindowSize(&oldrows, &oldcols) == 0) ? 1 : 0;
1258 	(void) kill(0, SIGTSTP);
1259 	/*
1260 	 * If we didn't get the window size before the SUSPEND, but we
1261 	 * can get them now (?), then send the NAWS to make sure that
1262 	 * we are set up for the right window size.
1263 	 */
1264 	if (TerminalWindowSize(&newrows, &newcols) && connected &&
1265 	    (err || ((oldrows != newrows) || (oldcols != newcols)))) {
1266 		sendnaws();
1267 	}
1268     }
1269     /* reget parameters in case they were changed */
1270     TerminalSaveState();
1271     setconnmode(0);
1272 #else
1273     printf("Suspend is not supported.  Try the '!' command instead\r\n");
1274 #endif
1275     return 1;
1276 }
1277 
1278     /*ARGSUSED*/
1279     int
1280 shell(argc, argv)
1281     int argc;
1282     char *argv[];
1283 {
1284     long oldrows, oldcols, newrows, newcols, err;
1285 
1286     setcommandmode();
1287 
1288     err = (TerminalWindowSize(&oldrows, &oldcols) == 0) ? 1 : 0;
1289     switch(vfork()) {
1290     case -1:
1291 	perror("Fork failed\r\n");
1292 	break;
1293 
1294     case 0:
1295 	{
1296 	    /*
1297 	     * Fire up the shell in the child.
1298 	     */
1299 	    char *shellp, *shellname;
1300 
1301 	    shellp = getenv("SHELL");
1302 	    if (shellp == NULL)
1303 		shellp = "/bin/sh";
1304 	    if ((shellname = strrchr(shellp, '/')) == 0)
1305 		shellname = shellp;
1306 	    else
1307 		shellname++;
1308 	    if (argc > 1)
1309 		execl(shellp, shellname, "-c", &saveline[1], (char *)NULL);
1310 	    else
1311 		execl(shellp, shellname, (char *)NULL);
1312 	    perror("Execl");
1313 	    _exit(1);
1314 	}
1315     default:
1316 	    (void)wait((int *)0);	/* Wait for the shell to complete */
1317 
1318 	    if (TerminalWindowSize(&newrows, &newcols) && connected &&
1319 		(err || ((oldrows != newrows) || (oldcols != newcols)))) {
1320 		    sendnaws();
1321 	    }
1322 	    break;
1323     }
1324     return 1;
1325 }
1326 
1327     /*VARARGS*/
1328     static int
1329 bye(argc, argv)
1330     int  argc;		/* Number of arguments */
1331     char *argv[];	/* arguments */
1332 {
1333     extern int resettermname;
1334 
1335     if (connected) {
1336 	(void) shutdown(net, 2);
1337 	printf("Connection closed.\r\n");
1338 	(void) NetClose(net);
1339 	connected = 0;
1340 	resettermname = 1;
1341 	/* reset options */
1342 	tninit();
1343     }
1344     if ((argc != 2) || (strcmp(argv[1], "fromquit") != 0)) {
1345 	longjmp(toplevel, 1);
1346 	/* NOTREACHED */
1347     }
1348     return 0; /* NOTREACHED */
1349 }
1350 
1351 /*VARARGS*/
1352 	int
1353 quit()
1354 {
1355 	(void) call(bye, "bye", "fromquit", 0);
1356 	Exit(0);
1357 	return 0; /*NOTREACHED*/
1358 }
1359 
1360 /*VARARGS*/
1361 	static int
1362 logout()
1363 {
1364 	send_do(TELOPT_LOGOUT, 1);
1365 	(void) netflush();
1366 	return 1;
1367 }
1368 
1369 
1370 /*
1371  * The SLC command.
1372  */
1373 
1374 struct slclist {
1375 	char	*name;
1376 	char	*help;
1377 	void	(*handler)();
1378 	int	arg;
1379 };
1380 
1381 static void slc_help();
1382 
1383 struct slclist SlcList[] = {
1384     { "export",	"Use local special character definitions",
1385 						slc_mode_export,	0 },
1386     { "import",	"Use remote special character definitions",
1387 						slc_mode_import,	1 },
1388     { "check",	"Verify remote special character definitions",
1389 						slc_mode_import,	0 },
1390     { "help",	0,				slc_help,		0 },
1391     { "?",	"Print help information",	slc_help,		0 },
1392     { 0 },
1393 };
1394 
1395     static void
1396 slc_help()
1397 {
1398     struct slclist *c;
1399 
1400     for (c = SlcList; c->name; c++) {
1401 	if (c->help) {
1402 	    if (*c->help)
1403 		printf("%-15s %s\r\n", c->name, c->help);
1404 	    else
1405 		printf("\r\n");
1406 	}
1407     }
1408 }
1409 
1410     static struct slclist *
1411 getslc(name)
1412     char *name;
1413 {
1414     return (struct slclist *)
1415 		genget(name, (char **) SlcList, sizeof(struct slclist));
1416 }
1417 
1418     static int
1419 slccmd(argc, argv)
1420     int  argc;
1421     char *argv[];
1422 {
1423     struct slclist *c;
1424 
1425     if (argc != 2) {
1426 	fprintf(stderr,
1427 	    "Need an argument to 'slc' command.  'slc ?' for help.\r\n");
1428 	return 0;
1429     }
1430     c = getslc(argv[1]);
1431     if (c == 0) {
1432 	fprintf(stderr, "'%s': unknown argument ('slc ?' for help).\r\n",
1433     				argv[1]);
1434 	return 0;
1435     }
1436     if (Ambiguous(c)) {
1437 	fprintf(stderr, "'%s': ambiguous argument ('slc ?' for help).\r\n",
1438     				argv[1]);
1439 	return 0;
1440     }
1441     (*c->handler)(c->arg);
1442     slcstate();
1443     return 1;
1444 }
1445 
1446 /*
1447  * The ENVIRON command.
1448  */
1449 
1450 struct envlist {
1451 	char	*name;
1452 	char	*help;
1453 	void	(*handler)();
1454 	int	narg;
1455 };
1456 
1457 static void	env_help(void);
1458 
1459 struct envlist EnvList[] = {
1460     { "define",	"Define an environment variable",
1461 						(void (*)())env_define,	2 },
1462     { "undefine", "Undefine an environment variable",
1463 						env_undefine,	1 },
1464     { "export",	"Mark an environment variable for automatic export",
1465 						env_export,	1 },
1466     { "unexport", "Don't mark an environment variable for automatic export",
1467 						env_unexport,	1 },
1468     { "send",	"Send an environment variable", env_send,	1 },
1469     { "list",	"List the current environment variables",
1470 						env_list,	0 },
1471     { "help",	0,				env_help,		0 },
1472     { "?",	"Print help information",	env_help,		0 },
1473     { 0 },
1474 };
1475 
1476     static void
1477 env_help()
1478 {
1479     struct envlist *c;
1480 
1481     for (c = EnvList; c->name; c++) {
1482 	if (c->help) {
1483 	    if (*c->help)
1484 		printf("%-15s %s\r\n", c->name, c->help);
1485 	    else
1486 		printf("\r\n");
1487 	}
1488     }
1489 }
1490 
1491     static struct envlist *
1492 getenvcmd(name)
1493     char *name;
1494 {
1495     return (struct envlist *)
1496 		genget(name, (char **) EnvList, sizeof(struct envlist));
1497 }
1498 
1499     int
1500 env_cmd(argc, argv)
1501     int  argc;
1502     char *argv[];
1503 {
1504     struct envlist *c;
1505 
1506     if (argc < 2) {
1507 	fprintf(stderr,
1508 	    "Need an argument to 'environ' command.  'environ ?' for help.\r\n");
1509 	return 0;
1510     }
1511     c = getenvcmd(argv[1]);
1512     if (c == 0) {
1513 	fprintf(stderr, "'%s': unknown argument ('environ ?' for help).\r\n",
1514     				argv[1]);
1515 	return 0;
1516     }
1517     if (Ambiguous(c)) {
1518 	fprintf(stderr, "'%s': ambiguous argument ('environ ?' for help).\r\n",
1519     				argv[1]);
1520 	return 0;
1521     }
1522     if (c->narg + 2 != argc) {
1523 	fprintf(stderr,
1524 	    "Need %s%d argument%s to 'environ %s' command.  'environ ?' for help.\r\n",
1525 		c->narg < argc + 2 ? "only " : "",
1526 		c->narg, c->narg == 1 ? "" : "s", c->name);
1527 	return 0;
1528     }
1529     (*c->handler)(argv[2], argv[3]);
1530     return 1;
1531 }
1532 
1533 struct env_lst {
1534 	struct env_lst *next;	/* pointer to next structure */
1535 	struct env_lst *prev;	/* pointer to previous structure */
1536 	unsigned char *var;	/* pointer to variable name */
1537 	unsigned char *value;	/* pointer to variable value */
1538 	int export;		/* 1 -> export with default list of variables */
1539 	int welldefined;	/* A well defined variable */
1540 };
1541 
1542 struct env_lst envlisthead;
1543 
1544 	struct env_lst *
1545 env_find(var)
1546 	unsigned char *var;
1547 {
1548 	struct env_lst *ep;
1549 
1550 	for (ep = envlisthead.next; ep; ep = ep->next) {
1551 		if (strcmp((char *)ep->var, (char *)var) == 0)
1552 			return(ep);
1553 	}
1554 	return(NULL);
1555 }
1556 
1557 	void
1558 env_init()
1559 {
1560 	extern char **environ;
1561 	char **epp, *cp;
1562 	struct env_lst *ep;
1563 
1564 	for (epp = environ; *epp; epp++) {
1565 		if ((cp = strchr(*epp, '='))) {
1566 			*cp = '\0';
1567 			ep = env_define((unsigned char *)*epp,
1568 					(unsigned char *)cp+1);
1569 			ep->export = 0;
1570 			*cp = '=';
1571 		}
1572 	}
1573 	/*
1574 	 * Special case for DISPLAY variable.  If it is ":0.0" or
1575 	 * "unix:0.0", we have to get rid of "unix" and insert our
1576 	 * hostname.
1577 	 */
1578 	if ((ep = env_find("DISPLAY"))
1579 	    && ((*ep->value == ':')
1580 		|| (strncmp((char *)ep->value, "unix:", 5) == 0))) {
1581 		char hbuf[MAXHOSTNAMELEN];
1582 		char *cp2 = strchr((char *)ep->value, ':');
1583 
1584 		gethostname(hbuf, sizeof hbuf);
1585 
1586 		/* If this is not the full name, try to get it via DNS */
1587 		if (strchr(hbuf, '.') == 0) {
1588 			struct hostent *he = gethostbyname(hbuf);
1589 			if (he != 0)
1590 				strncpy(hbuf, he->h_name, sizeof hbuf-1);
1591 			hbuf[sizeof hbuf-1] = '\0';
1592 		}
1593 
1594 		if (asprintf (&cp, "%s%s", hbuf, cp2) == -1)
1595 			err(1, "asprintf");
1596 
1597 		free(ep->value);
1598 		ep->value = (unsigned char *)cp;
1599 	}
1600 	/*
1601 	 * If USER is not defined, but LOGNAME is, then add
1602 	 * USER with the value from LOGNAME.  By default, we
1603 	 * don't export the USER variable.
1604 	 */
1605 	if ((env_find("USER") == NULL) && (ep = env_find("LOGNAME"))) {
1606 		env_define((unsigned char *)"USER", ep->value);
1607 		env_unexport((unsigned char *)"USER");
1608 	}
1609 	env_export((unsigned char *)"DISPLAY");
1610 	env_export((unsigned char *)"PRINTER");
1611 	env_export((unsigned char *)"XAUTHORITY");
1612 }
1613 
1614 	struct env_lst *
1615 env_define(var, value)
1616 	unsigned char *var, *value;
1617 {
1618 	struct env_lst *ep;
1619 
1620 	if ((ep = env_find(var))) {
1621 		if (ep->var)
1622 			free(ep->var);
1623 		if (ep->value)
1624 			free(ep->value);
1625 	} else {
1626 		if ((ep = malloc(sizeof(struct env_lst))) == NULL)
1627 			err(1, "malloc");
1628 		ep->next = envlisthead.next;
1629 		envlisthead.next = ep;
1630 		ep->prev = &envlisthead;
1631 		if (ep->next)
1632 			ep->next->prev = ep;
1633 	}
1634 	ep->welldefined = opt_welldefined((char *)var);
1635 	ep->export = 1;
1636 	if ((ep->var = strdup((char *)var)) == NULL)
1637 		err(1, "strdup");
1638 	if ((ep->value = strdup((char *)value)) == NULL)
1639 		err(1, "strdup");
1640 	return(ep);
1641 }
1642 
1643 	void
1644 env_undefine(var)
1645 	unsigned char *var;
1646 {
1647 	struct env_lst *ep;
1648 
1649 	if ((ep = env_find(var))) {
1650 		ep->prev->next = ep->next;
1651 		if (ep->next)
1652 			ep->next->prev = ep->prev;
1653 		if (ep->var)
1654 			free(ep->var);
1655 		if (ep->value)
1656 			free(ep->value);
1657 		free(ep);
1658 	}
1659 }
1660 
1661 	void
1662 env_export(var)
1663 	unsigned char *var;
1664 {
1665 	struct env_lst *ep;
1666 
1667 	if ((ep = env_find(var)))
1668 		ep->export = 1;
1669 }
1670 
1671 	void
1672 env_unexport(var)
1673 	unsigned char *var;
1674 {
1675 	struct env_lst *ep;
1676 
1677 	if ((ep = env_find(var)) != NULL)
1678 		ep->export = 0;
1679 }
1680 
1681 	void
1682 env_send(var)
1683 	unsigned char *var;
1684 {
1685 	struct env_lst *ep;
1686 
1687 	if (my_state_is_wont(TELOPT_NEW_ENVIRON)
1688 		) {
1689 		fprintf(stderr,
1690 		    "Cannot send '%s': Telnet ENVIRON option not enabled\r\n",
1691 									var);
1692 		return;
1693 	}
1694 	ep = env_find(var);
1695 	if (ep == 0) {
1696 		fprintf(stderr, "Cannot send '%s': variable not defined\r\n",
1697 									var);
1698 		return;
1699 	}
1700 	env_opt_start_info();
1701 	env_opt_add(ep->var);
1702 	env_opt_end(0);
1703 }
1704 
1705 	void
1706 env_list()
1707 {
1708 	struct env_lst *ep;
1709 
1710 	for (ep = envlisthead.next; ep; ep = ep->next) {
1711 		printf("%c %-20s %s\r\n", ep->export ? '*' : ' ',
1712 					ep->var, ep->value);
1713 	}
1714 }
1715 
1716 	unsigned char *
1717 env_default(init, welldefined)
1718 	int init;
1719 {
1720 	static struct env_lst *nep = NULL;
1721 
1722 	if (init) {
1723 		nep = &envlisthead;
1724 		return NULL;
1725 	}
1726 	if (nep) {
1727 		while ((nep = nep->next)) {
1728 			if (nep->export && (nep->welldefined == welldefined))
1729 				return(nep->var);
1730 		}
1731 	}
1732 	return(NULL);
1733 }
1734 
1735 	unsigned char *
1736 env_getvalue(var, exported_only)
1737 	unsigned char *var;
1738 	int exported_only;
1739 {
1740 	struct env_lst *ep;
1741 
1742 	if ((ep = env_find(var)) && (!exported_only || ep->export))
1743 		return(ep->value);
1744 	return(NULL);
1745 }
1746 
1747 /*
1748  * Print status about the connection.
1749  */
1750     /*ARGSUSED*/
1751     static int
1752 status(argc, argv)
1753     int	 argc;
1754     char *argv[];
1755 {
1756     if (connected) {
1757 	printf("Connected to %s.\r\n", hostname);
1758 	if ((argc < 2) || strcmp(argv[1], "notmuch")) {
1759 	    int mode = getconnmode();
1760 
1761 	    if (my_want_state_is_will(TELOPT_LINEMODE)) {
1762 		printf("Operating with LINEMODE option\r\n");
1763 		printf("%s line editing\r\n", (mode&MODE_EDIT) ? "Local" : "No");
1764 		printf("%s catching of signals\r\n",
1765 					(mode&MODE_TRAPSIG) ? "Local" : "No");
1766 		slcstate();
1767 #ifdef	KLUDGELINEMODE
1768 	    } else if (kludgelinemode && my_want_state_is_dont(TELOPT_SGA)) {
1769 		printf("Operating in obsolete linemode\r\n");
1770 #endif
1771 	    } else {
1772 		printf("Operating in single character mode\r\n");
1773 		if (localchars)
1774 		    printf("Catching signals locally\r\n");
1775 	    }
1776 	    printf("%s character echo\r\n", (mode&MODE_ECHO) ? "Local" : "Remote");
1777 	    if (my_want_state_is_will(TELOPT_LFLOW))
1778 		printf("%s flow control\r\n", (mode&MODE_FLOW) ? "Local" : "No");
1779 	}
1780     } else {
1781 	printf("No connection.\r\n");
1782     }
1783     printf("Escape character is '%s'.\r\n", control(escape));
1784     (void) fflush(stdout);
1785     fflush(stdout);
1786     return 1;
1787 }
1788 
1789 #ifdef	SIGINFO
1790 /*
1791  * Function that gets called when SIGINFO is received.
1792  */
1793 void
1794 ayt_status()
1795 {
1796     (void) call(status, "status", "notmuch", 0);
1797 }
1798 #endif
1799 
1800 static Command *getcmd(char *name);
1801 
1802 static void
1803 cmdrc(char *m1, char *m2)
1804 {
1805     static char rcname[128];
1806     Command *c;
1807     FILE *rcfile;
1808     int gotmachine = 0;
1809     int l1 = strlen(m1);
1810     int l2 = strlen(m2);
1811     char m1save[MAXHOSTNAMELEN];
1812 
1813     if (skiprc)
1814 	return;
1815 
1816     strlcpy(m1save, m1, sizeof(m1save));
1817     m1 = m1save;
1818 
1819     if (rcname[0] == 0) {
1820 	char *home = getenv("HOME");
1821 
1822 	if (home == NULL || *home == '\0')
1823 	    return;
1824 	snprintf (rcname, sizeof(rcname), "%s/.telnetrc",
1825 		  home ? home : "");
1826     }
1827 
1828     if ((rcfile = fopen(rcname, "r")) == 0) {
1829 	return;
1830     }
1831 
1832     for (;;) {
1833 	if (fgets(line, sizeof(line), rcfile) == NULL)
1834 	    break;
1835 	if (line[0] == 0)
1836 	    break;
1837 	if (line[0] == '#')
1838 	    continue;
1839 	if (gotmachine) {
1840 	    if (!isspace(line[0]))
1841 		gotmachine = 0;
1842 	}
1843 	if (gotmachine == 0) {
1844 	    if (isspace(line[0]))
1845 		continue;
1846 	    if (strncasecmp(line, m1, l1) == 0)
1847 		strncpy(line, &line[l1], sizeof(line) - l1);
1848 	    else if (strncasecmp(line, m2, l2) == 0)
1849 		strncpy(line, &line[l2], sizeof(line) - l2);
1850 	    else if (strncasecmp(line, "DEFAULT", 7) == 0)
1851 		strncpy(line, &line[7], sizeof(line) - 7);
1852 	    else
1853 		continue;
1854 	    if (line[0] != ' ' && line[0] != '\t' && line[0] != '\n')
1855 		continue;
1856 	    gotmachine = 1;
1857 	}
1858 	makeargv();
1859 	if (margv[0] == 0)
1860 	    continue;
1861 	c = getcmd(margv[0]);
1862 	if (Ambiguous(c)) {
1863 	    printf("?Ambiguous command: %s\r\n", margv[0]);
1864 	    continue;
1865 	}
1866 	if (c == 0) {
1867 	    printf("?Invalid command: %s\r\n", margv[0]);
1868 	    continue;
1869 	}
1870 	/*
1871 	 * This should never happen...
1872 	 */
1873 	if (c->needconnect && !connected) {
1874 	    printf("?Need to be connected first for %s.\r\n", margv[0]);
1875 	    continue;
1876 	}
1877 	(*c->handler)(margc, margv);
1878     }
1879     fclose(rcfile);
1880 }
1881 
1882 
1883     int
1884 tn(argc, argv)
1885     int argc;
1886     char *argv[];
1887 {
1888     struct addrinfo hints, *res, *res0;
1889     int error;
1890     struct sockaddr_in sin;
1891     unsigned long temp;
1892     extern char *inet_ntoa();
1893     char *srp = 0;
1894     int srlen;
1895     char *cmd, *hostp = 0, *portp = 0, *user = 0, *aliasp = 0;
1896     int retry;
1897     const int niflags = NI_NUMERICHOST;
1898 
1899     /* clear the socket address prior to use */
1900     memset((char *)&sin, 0, sizeof(sin));
1901 
1902     if (connected) {
1903 	printf("?Already connected to %s\r\n", hostname);
1904 	return 0;
1905     }
1906     if (argc < 2) {
1907 	strlcpy(line, "open ", sizeof(line));
1908 	printf("(to) ");
1909 	(void) fgets(&line[strlen(line)], sizeof(line) - strlen(line), stdin);
1910 	makeargv();
1911 	argc = margc;
1912 	argv = margv;
1913     }
1914     cmd = *argv;
1915     --argc; ++argv;
1916     while (argc) {
1917 	if (strcmp(*argv, "help") == 0 || isprefix(*argv, "?"))
1918 	    goto usage;
1919 	if (strcmp(*argv, "-l") == 0) {
1920 	    --argc; ++argv;
1921 	    if (argc == 0)
1922 		goto usage;
1923 	    if ((user = strdup(*argv++)) == NULL)
1924 		err(1, "strdup");
1925 	    --argc;
1926 	    continue;
1927 	}
1928 	if (strcmp(*argv, "-b") == 0) {
1929 	    --argc; ++argv;
1930 	    if (argc == 0)
1931 		goto usage;
1932 	    aliasp = *argv++;
1933 	    --argc;
1934 	    continue;
1935 	}
1936 	if (strcmp(*argv, "-a") == 0) {
1937 	    --argc; ++argv;
1938 	    autologin = 1;
1939 	    continue;
1940 	}
1941 	if (hostp == 0) {
1942 	    hostp = *argv++;
1943 	    --argc;
1944 	    continue;
1945 	}
1946 	if (portp == 0) {
1947 	    portp = *argv++;
1948 	    --argc;
1949 	    continue;
1950 	}
1951     usage:
1952 	printf("usage: %s [-a] [-b hostalias] [-l user] host-name [port]\r\n", cmd);
1953 	return 0;
1954     }
1955     if (hostp == 0)
1956 	goto usage;
1957 
1958     if (hostp[0] == '@' || hostp[0] == '!') {
1959 	if ((hostname = strrchr(hostp, ':')) == NULL)
1960 	    hostname = strrchr(hostp, '@');
1961 	hostname++;
1962 	srp = 0;
1963 	temp = sourceroute(hostp, &srp, &srlen);
1964 	if (temp == 0) {
1965 	    herror(srp);
1966 	    return 0;
1967 	} else if (temp == -1) {
1968 	    printf("Bad source route option: %s\r\n", hostp);
1969 	    return 0;
1970 	} else {
1971 	    abort();
1972 	}
1973     } else
1974     {
1975 	hostname = hostp;
1976 	memset(&hints, 0, sizeof(hints));
1977 	hints.ai_family = family;
1978 	hints.ai_socktype = SOCK_STREAM;
1979 	hints.ai_flags = AI_CANONNAME;
1980 	if (portp == NULL) {
1981 	    portp = "telnet";
1982 	    telnetport = 1;
1983 	} else if (*portp == '-') {
1984 	    portp++;
1985 	    telnetport = 1;
1986 	} else
1987 	    telnetport = 0;
1988 	h_errno = 0;
1989 	error = getaddrinfo(hostp, portp, &hints, &res0);
1990 	if (error) {
1991 	    if (error == EAI_SERVICE)
1992 		warnx("%s: bad port", portp);
1993 	    else
1994 		warnx("%s: %s", hostp, gai_strerror(error));
1995 	    if (h_errno)
1996 		herror(hostp);
1997 	    return 0;
1998 	}
1999     }
2000 
2001     net = -1;
2002     retry = 0;
2003     for (res = res0; res; res = res->ai_next) {
2004 	if (1 /* retry */) {
2005 	    char hbuf[NI_MAXHOST];
2006 
2007 	    if (getnameinfo(res->ai_addr, res->ai_addrlen, hbuf, sizeof(hbuf),
2008 		    NULL, 0, niflags) != 0) {
2009 		strlcpy(hbuf, "(invalid)", sizeof(hbuf));
2010 	    }
2011 	    printf("Trying %s...\r\n", hbuf);
2012 	}
2013 	net = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
2014 	if (net < 0)
2015 	    continue;
2016 
2017 	if (rtableid >= 0 && (setsockopt(net, SOL_SOCKET, SO_RTABLE, &rtableid,
2018 	    sizeof(rtableid)) == -1))
2019 		perror("setsockopt (SO_RTABLE)");
2020 
2021 	if (aliasp) {
2022 	    struct addrinfo ahints, *ares;
2023 
2024 	    memset(&ahints, 0, sizeof(ahints));
2025 	    ahints.ai_family = family;
2026 	    ahints.ai_socktype = SOCK_STREAM;
2027 	    ahints.ai_flags = AI_PASSIVE;
2028 	    error = getaddrinfo(aliasp, "0", &ahints, &ares);
2029 	    if (error) {
2030 		warn("%s: %s", aliasp, gai_strerror(error));
2031 		close(net);
2032 		net = -1;
2033 		continue;
2034 	    }
2035 	    if (bind(net, ares->ai_addr, ares->ai_addrlen) < 0) {
2036 		perror(aliasp);
2037 		(void) close(net);   /* dump descriptor */
2038 		net = -1;
2039 		freeaddrinfo(ares);
2040 		continue;
2041             }
2042 	    freeaddrinfo(ares);
2043 	}
2044 	if (srp && res->ai_family == AF_INET
2045 	 && setsockopt(net, IPPROTO_IP, IP_OPTIONS, srp, srlen) < 0)
2046 		perror("setsockopt (IP_OPTIONS)");
2047 	if (res->ai_family == AF_INET) {
2048 	    if (tos < 0)
2049 		tos = IPTOS_LOWDELAY;	/* Low Delay bit */
2050 	    if (tos
2051 		&& (setsockopt(net, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
2052 		&& (errno != ENOPROTOOPT))
2053 		    perror("telnet: setsockopt (IP_TOS) (ignored)");
2054 	}
2055 
2056 	if (debug) {
2057 		int one = 1;
2058 
2059 		if (setsockopt(net, SOL_SOCKET, SO_DEBUG, &one,
2060 		    sizeof(one)) < 0)
2061 			perror("setsockopt (SO_DEBUG)");
2062 	}
2063 
2064 	if (connect(net, res->ai_addr, res->ai_addrlen) < 0) {
2065 	    char hbuf[NI_MAXHOST];
2066 
2067 	    if (getnameinfo(res->ai_addr, res->ai_addrlen, hbuf, sizeof(hbuf),
2068 		    NULL, 0, niflags) != 0) {
2069 		strlcpy(hbuf, "(invalid)", sizeof(hbuf));
2070 	    }
2071 	    fprintf(stderr, "telnet: connect to address %s: %s\n", hbuf,
2072 		strerror(errno));
2073 
2074 	    close(net);
2075 	    net = -1;
2076 	    retry++;
2077 	    continue;
2078 	}
2079 
2080 	connected++;
2081 	break;
2082     }
2083     freeaddrinfo(res0);
2084     if (net < 0) {
2085 	return 0;
2086     }
2087     cmdrc(hostp, hostname);
2088     if (autologin && user == NULL) {
2089 	struct passwd *pw;
2090 
2091 	user = getenv("USER");
2092 	if (user == NULL ||
2093 	    ((pw = getpwnam(user)) && pw->pw_uid != getuid())) {
2094 		if ((pw = getpwuid(getuid())) != NULL)
2095 			user = pw->pw_name;
2096 		else
2097 			user = NULL;
2098 	}
2099     }
2100     if (user) {
2101 	env_define((unsigned char *)"USER", (unsigned char *)user);
2102 	env_export((unsigned char *)"USER");
2103     }
2104     (void) call(status, "status", "notmuch", 0);
2105     if (setjmp(peerdied) == 0)
2106 	telnet(user);
2107     (void) NetClose(net);
2108     ExitString("Connection closed by foreign host.\r\n",1);
2109     /*NOTREACHED*/
2110     return 0;
2111 }
2112 
2113 #define HELPINDENT (sizeof ("connect"))
2114 
2115 static char
2116 	openhelp[] =	"connect to a site",
2117 	closehelp[] =	"close current connection",
2118 	logouthelp[] =	"forcibly logout remote user and close the connection",
2119 	quithelp[] =	"exit telnet",
2120 	statushelp[] =	"print status information",
2121 	helphelp[] =	"print help information",
2122 	sendhelp[] =	"transmit special characters ('send ?' for more)",
2123 	sethelp[] = 	"set operating parameters ('set ?' for more)",
2124 	unsethelp[] = 	"unset operating parameters ('unset ?' for more)",
2125 	togglestring[] ="toggle operating parameters ('toggle ?' for more)",
2126 	slchelp[] =	"change state of special charaters ('slc ?' for more)",
2127 	displayhelp[] =	"display operating parameters",
2128 	zhelp[] =	"suspend telnet",
2129 #ifdef SKEY
2130 	skeyhelp[] =	"compute response to s/key challenge",
2131 #endif
2132 	shellhelp[] =	"invoke a subshell",
2133 	envhelp[] =	"change environment variables ('environ ?' for more)",
2134 	modestring[] = "try to enter line or character mode ('mode ?' for more)";
2135 
2136 static int	help(int, char**);
2137 
2138 static Command cmdtab[] = {
2139 	{ "close",	closehelp,	bye,		1 },
2140 	{ "logout",	logouthelp,	logout,		1 },
2141 	{ "display",	displayhelp,	display,	0 },
2142 	{ "mode",	modestring,	modecmd,	0 },
2143 	{ "open",	openhelp,	tn,		0 },
2144 	{ "quit",	quithelp,	quit,		0 },
2145 	{ "send",	sendhelp,	sendcmd,	0 },
2146 	{ "set",	sethelp,	setcmd,		0 },
2147 	{ "unset",	unsethelp,	unsetcmd,	0 },
2148 	{ "status",	statushelp,	status,		0 },
2149 	{ "toggle",	togglestring,	toggle,		0 },
2150 	{ "slc",	slchelp,	slccmd,		0 },
2151 
2152 	{ "z",		zhelp,		telnetsuspend,	0 },
2153 	{ "!",		shellhelp,	shell,		0 },
2154 	{ "environ",	envhelp,	env_cmd,	0 },
2155 	{ "?",		helphelp,	help,		0 },
2156 #if	defined(SKEY)
2157 	{ "skey",	skeyhelp,	skey_calc,	0 },
2158 #endif
2159 	{ 0,		0,		0,		0 }
2160 };
2161 
2162 static char	crmodhelp[] =	"deprecated command -- use 'toggle crmod' instead";
2163 static char	escapehelp[] =	"deprecated command -- use 'set escape' instead";
2164 
2165 static Command cmdtab2[] = {
2166 	{ "help",	0,		help,		0 },
2167 	{ "escape",	escapehelp,	setescape,	0 },
2168 	{ "crmod",	crmodhelp,	togcrmod,	0 },
2169 	{ 0,		0,		0,		0 }
2170 };
2171 
2172 
2173 /*
2174  * Call routine with argc, argv set from args (terminated by 0).
2175  */
2176 
2177     /*VARARGS1*/
2178     static int
2179 call(intrtn_t routine, ...)
2180 {
2181     va_list ap;
2182     char *args[100];
2183     int argno = 0;
2184 
2185     va_start(ap, routine);
2186     while ((args[argno++] = va_arg(ap, char *)) != 0);
2187     va_end(ap);
2188     return (*routine)(argno-1, args);
2189 }
2190 
2191 
2192     static Command *
2193 getcmd(name)
2194     char *name;
2195 {
2196     Command *cm;
2197 
2198     if ((cm = (Command *) genget(name, (char **) cmdtab, sizeof(Command))))
2199 	return cm;
2200     return (Command *) genget(name, (char **) cmdtab2, sizeof(Command));
2201 }
2202 
2203     void
2204 command(top, tbuf, cnt)
2205     int top;
2206     char *tbuf;
2207     int cnt;
2208 {
2209     Command *c;
2210 
2211     setcommandmode();
2212     if (!top) {
2213 	putchar('\n');
2214     } else {
2215 	(void) signal(SIGINT, SIG_DFL);
2216 	(void) signal(SIGQUIT, SIG_DFL);
2217     }
2218     for (;;) {
2219 	if (rlogin == _POSIX_VDISABLE)
2220 		printf("%s> ", prompt);
2221 	if (tbuf) {
2222 	    char *cp;
2223 	    cp = line;
2224 	    while (cnt > 0 && (*cp++ = *tbuf++) != '\n')
2225 		cnt--;
2226 	    tbuf = 0;
2227 	    if (cp == line || *--cp != '\n' || cp == line)
2228 		goto getline;
2229 	    *cp = '\0';
2230 	    if (rlogin == _POSIX_VDISABLE)
2231 		printf("%s\r\n", line);
2232 	} else {
2233 	getline:
2234 	    if (rlogin != _POSIX_VDISABLE)
2235 		printf("%s> ", prompt);
2236 	    if (fgets(line, sizeof(line), stdin) == NULL) {
2237 		if (feof(stdin) || ferror(stdin)) {
2238 		    (void) quit();
2239 		    /*NOTREACHED*/
2240 		}
2241 		break;
2242 	    }
2243 	}
2244 	if (line[0] == 0)
2245 	    break;
2246 	makeargv();
2247 	if (margv[0] == 0) {
2248 	    break;
2249 	}
2250 	c = getcmd(margv[0]);
2251 	if (Ambiguous(c)) {
2252 	    printf("?Ambiguous command\r\n");
2253 	    continue;
2254 	}
2255 	if (c == 0) {
2256 	    printf("?Invalid command\r\n");
2257 	    continue;
2258 	}
2259 	if (c->needconnect && !connected) {
2260 	    printf("?Need to be connected first.\r\n");
2261 	    continue;
2262 	}
2263 	if ((*c->handler)(margc, margv)) {
2264 	    break;
2265 	}
2266     }
2267     if (!top) {
2268 	if (!connected) {
2269 	    longjmp(toplevel, 1);
2270 	    /*NOTREACHED*/
2271 	}
2272 	setconnmode(0);
2273     }
2274 }
2275 
2276 /*
2277  * Help command.
2278  */
2279 	static int
2280 help(argc, argv)
2281 	int argc;
2282 	char *argv[];
2283 {
2284 	Command *c;
2285 
2286 	if (argc == 1) {
2287 		printf("Commands may be abbreviated.  Commands are:\r\n\r\n");
2288 		for (c = cmdtab; c->name; c++)
2289 			if (c->help) {
2290 				printf("%-*s\t%s\r\n", (int)HELPINDENT, c->name,
2291 								    c->help);
2292 			}
2293 		return 0;
2294 	}
2295 	while (--argc > 0) {
2296 		char *arg;
2297 		arg = *++argv;
2298 		c = getcmd(arg);
2299 		if (Ambiguous(c))
2300 			printf("?Ambiguous help command %s\r\n", arg);
2301 		else if (c == (Command *)0)
2302 			printf("?Invalid help command %s\r\n", arg);
2303 		else
2304 			printf("%s\r\n", c->help);
2305 	}
2306 	return 0;
2307 }
2308 
2309 /*
2310  * Source route is handed in as
2311  *	[!]@hop1@hop2...[@|:]dst
2312  * If the leading ! is present, it is a
2313  * strict source route, otherwise it is
2314  * assmed to be a loose source route.
2315  *
2316  * We fill in the source route option as
2317  *	hop1,hop2,hop3...dest
2318  * and return a pointer to hop1, which will
2319  * be the address to connect() to.
2320  *
2321  * Arguments:
2322  *	arg:	pointer to route list to decipher
2323  *
2324  *	cpp: 	If *cpp is not equal to NULL, this is a
2325  *		pointer to a pointer to a character array
2326  *		that should be filled in with the option.
2327  *
2328  *	lenp:	pointer to an integer that contains the
2329  *		length of *cpp if *cpp != NULL.
2330  *
2331  * Return values:
2332  *
2333  *	Returns the address of the host to connect to.  If the
2334  *	return value is -1, there was a syntax error in the
2335  *	option, either unknown characters, or too many hosts.
2336  *	If the return value is 0, one of the hostnames in the
2337  *	path is unknown, and *cpp is set to point to the bad
2338  *	hostname.
2339  *
2340  *	*cpp:	If *cpp was equal to NULL, it will be filled
2341  *		in with a pointer to our static area that has
2342  *		the option filled in.  This will be 32bit aligned.
2343  *
2344  *	*lenp:	This will be filled in with how long the option
2345  *		pointed to by *cpp is.
2346  *
2347  */
2348 	unsigned long
2349 sourceroute(arg, cpp, lenp)
2350 	char	*arg;
2351 	char	**cpp;
2352 	int	*lenp;
2353 {
2354 	static char lsr[44];
2355 	char *cp, *cp2, *lsrp, *lsrep;
2356 	int tmp;
2357 	struct in_addr sin_addr;
2358 	struct hostent *host = 0;
2359 	char c;
2360 
2361 	/*
2362 	 * Verify the arguments, and make sure we have
2363 	 * at least 7 bytes for the option.
2364 	 */
2365 	if (cpp == NULL || lenp == NULL)
2366 		return((unsigned long)-1);
2367 	if (*cpp != NULL && *lenp < 7)
2368 		return((unsigned long)-1);
2369 	/*
2370 	 * Decide whether we have a buffer passed to us,
2371 	 * or if we need to use our own static buffer.
2372 	 */
2373 	if (*cpp) {
2374 		lsrp = *cpp;
2375 		lsrep = lsrp + *lenp;
2376 	} else {
2377 		*cpp = lsrp = lsr;
2378 		lsrep = lsrp + 44;
2379 	}
2380 
2381 	cp = arg;
2382 
2383 	/*
2384 	 * Next, decide whether we have a loose source
2385 	 * route or a strict source route, and fill in
2386 	 * the begining of the option.
2387 	 */
2388 	if (*cp == '!') {
2389 		cp++;
2390 		*lsrp++ = IPOPT_SSRR;
2391 	} else
2392 		*lsrp++ = IPOPT_LSRR;
2393 
2394 	if (*cp != '@')
2395 		return((unsigned long)-1);
2396 
2397 	lsrp++;		/* skip over length, we'll fill it in later */
2398 	*lsrp++ = 4;
2399 
2400 	cp++;
2401 
2402 	sin_addr.s_addr = 0;
2403 
2404 	for (c = 0;;) {
2405 		if (c == ':')
2406 			cp2 = 0;
2407 		else for (cp2 = cp; (c = *cp2); cp2++) {
2408 			if (c == ',') {
2409 				*cp2++ = '\0';
2410 				if (*cp2 == '@')
2411 					cp2++;
2412 			} else if (c == '@') {
2413 				*cp2++ = '\0';
2414 			} else if (c == ':') {
2415 				*cp2++ = '\0';
2416 			} else
2417 				continue;
2418 			break;
2419 		}
2420 		if (!c)
2421 			cp2 = 0;
2422 
2423 		if ((tmp = inet_addr(cp)) != -1) {
2424 			sin_addr.s_addr = tmp;
2425 		} else if ((host = gethostbyname(cp))) {
2426 			memmove((caddr_t)&sin_addr,
2427 				host->h_addr_list[0],
2428 				sizeof(sin_addr));
2429 		} else {
2430 			*cpp = cp;
2431 			return(0);
2432 		}
2433 		memmove(lsrp, (char *)&sin_addr, 4);
2434 		lsrp += 4;
2435 		if (cp2)
2436 			cp = cp2;
2437 		else
2438 			break;
2439 		/*
2440 		 * Check to make sure there is space for next address
2441 		 */
2442 		if (lsrp + 4 > lsrep)
2443 			return((unsigned long)-1);
2444 	}
2445 	if ((*(*cpp+IPOPT_OLEN) = lsrp - *cpp) <= 7) {
2446 		*cpp = 0;
2447 		*lenp = 0;
2448 		return((unsigned long)-1);
2449 	}
2450 	*lsrp++ = IPOPT_NOP; /* 32 bit word align it */
2451 	*lenp = lsrp - *cpp;
2452 	return(sin_addr.s_addr);
2453 }
2454