xref: /netbsd-src/usr.bin/tip/tip.c (revision 1394f01b4a9e99092957ca5d824d67219565d9b5)
1 /*	$NetBSD: tip.c,v 1.14 1997/05/14 00:20:05 mellon Exp $	*/
2 
3 /*
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 static char copyright[] =
38 "@(#) Copyright (c) 1983, 1993\n\
39 	The Regents of the University of California.  All rights reserved.\n";
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)tip.c	8.1 (Berkeley) 6/6/93";
45 #endif
46 static char rcsid[] = "$NetBSD: tip.c,v 1.14 1997/05/14 00:20:05 mellon Exp $";
47 #endif /* not lint */
48 
49 /*
50  * tip - UNIX link to other systems
51  *  tip [-v] [-speed] system-name
52  * or
53  *  cu phone-number [-s speed] [-l line] [-a acu]
54  */
55 #include "tip.h"
56 #include "pathnames.h"
57 
58 /*
59  * Baud rate mapping table
60  */
61 int rates[] = {
62 	0, 50, 75, 110, 134, 150, 200, 300, 600,
63 	1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200, -1
64 };
65 
66 int	disc = TTYDISC;		/* tip normally runs this way */
67 void	intprompt();
68 void	timeout();
69 void	cleanup();
70 char	*sname();
71 char	PNbuf[256];			/* This limits the size of a number */
72 
73 main(argc, argv)
74 	char *argv[];
75 {
76 	char *system = NOSTR;
77 	register int i;
78 	register char *p;
79 	char sbuf[12];
80 
81 	gid = getgid();
82 	egid = getegid();
83 	uid = getuid();
84 	euid = geteuid();
85 	if (equal(sname(argv[0]), "cu")) {
86 		cumode = 1;
87 		cumain(argc, argv);
88 		goto cucommon;
89 	}
90 
91 	if (argc > 4) {
92 		fprintf(stderr, "usage: tip [-v] [-speed] [system-name]\n");
93 		exit(1);
94 	}
95 	if (!isatty(0)) {
96 		fprintf(stderr, "tip: must be interactive\n");
97 		exit(1);
98 	}
99 
100 	for (; argc > 1; argv++, argc--) {
101 		if (argv[1][0] != '-')
102 			system = argv[1];
103 		else switch (argv[1][1]) {
104 
105 		case 'v':
106 			vflag++;
107 			break;
108 
109 		case '0': case '1': case '2': case '3': case '4':
110 		case '5': case '6': case '7': case '8': case '9':
111 			BR = atoi(&argv[1][1]);
112 			break;
113 
114 		default:
115 			fprintf(stderr, "tip: %s, unknown option\n", argv[1]);
116 			break;
117 		}
118 	}
119 
120 	if (system == NOSTR)
121 		goto notnumber;
122 	if (isalpha(*system))
123 		goto notnumber;
124 	/*
125 	 * System name is really a phone number...
126 	 * Copy the number then stomp on the original (in case the number
127 	 *	is private, we don't want 'ps' or 'w' to find it).
128 	 */
129 	if (strlen(system) > sizeof PNbuf - 1) {
130 		fprintf(stderr, "tip: phone number too long (max = %d bytes)\n",
131 			sizeof PNbuf - 1);
132 		exit(1);
133 	}
134 	strncpy( PNbuf, system, sizeof PNbuf - 1 );
135 	for (p = system; *p; p++)
136 		*p = '\0';
137 	PN = PNbuf;
138 	(void)snprintf(sbuf, sizeof sbuf, "tip%d", BR);
139 	system = sbuf;
140 
141 notnumber:
142 	(void)signal(SIGINT, cleanup);
143 	(void)signal(SIGQUIT, cleanup);
144 	(void)signal(SIGHUP, cleanup);
145 	(void)signal(SIGTERM, cleanup);
146 
147 	if ((i = hunt(system)) == 0) {
148 		printf("all ports busy\n");
149 		exit(3);
150 	}
151 	if (i == -1) {
152 		printf("link down\n");
153 		(void)uu_unlock(uucplock);
154 		exit(3);
155 	}
156 	setbuf(stdout, NULL);
157 	loginit();
158 
159 	/*
160 	 * Now that we have the logfile and the ACU open
161 	 *  return to the real uid and gid.  These things will
162 	 *  be closed on exit.  Swap real and effective uid's
163 	 *  so we can get the original permissions back
164 	 *  for removing the uucp lock.
165 	 */
166 	user_uid();
167 
168 	/*
169 	 * Kludge, their's no easy way to get the initialization
170 	 *   in the right order, so force it here
171 	 */
172 	if ((PH = getenv("PHONES")) == NOSTR)
173 		PH = _PATH_PHONES;
174 	vinit();				/* init variables */
175 	setparity("even");			/* set the parity table */
176 	if ((i = speed(number(value(BAUDRATE)))) == 0) {
177 		printf("tip: bad baud rate %d\n", number(value(BAUDRATE)));
178 		daemon_uid();
179 		(void)uu_unlock(uucplock);
180 		exit(3);
181 	}
182 
183 	/*
184 	 * Hardwired connections require the
185 	 *  line speed set before they make any transmissions
186 	 *  (this is particularly true of things like a DF03-AC)
187 	 */
188 	if (HW)
189 		ttysetup(i);
190 	if (p = connect()) {
191 		printf("\07%s\n[EOT]\n", p);
192 		daemon_uid();
193 		(void)uu_unlock(uucplock);
194 		exit(1);
195 	}
196 	if (!HW)
197 		ttysetup(i);
198 cucommon:
199 	/*
200 	 * From here down the code is shared with
201 	 * the "cu" version of tip.
202 	 */
203 
204 	tcgetattr(0, &defterm);
205 	term = defterm;
206 	term.c_lflag &= ~(ICANON|IEXTEN|ECHO);
207 	term.c_iflag &= ~(INPCK|ICRNL);
208 	term.c_oflag &= ~OPOST;
209 	term.c_cc[VMIN] = 1;
210 	term.c_cc[VTIME] = 0;
211 	defchars = term;
212 	term.c_cc[VINTR] = term.c_cc[VQUIT] = term.c_cc[VSUSP] =
213 		term.c_cc[VDSUSP] = term.c_cc[VDISCARD] =
214 	 	term.c_cc[VLNEXT] = _POSIX_VDISABLE;
215 	raw();
216 
217 	pipe(fildes); pipe(repdes);
218 	(void)signal(SIGALRM, timeout);
219 
220 	/*
221 	 * Everything's set up now:
222 	 *	connection established (hardwired or dialup)
223 	 *	line conditioned (baud rate, mode, etc.)
224 	 *	internal data structures (variables)
225 	 * so, fork one process for local side and one for remote.
226 	 */
227 	printf(cumode ? "Connected\r\n" : "\07connected\r\n");
228 	if (pid = fork())
229 		tipin();
230 	else
231 		tipout();
232 	/*NOTREACHED*/
233 }
234 
235 void
236 cleanup()
237 {
238 
239 	daemon_uid();
240 	(void)uu_unlock(uucplock);
241 	if (odisc)
242 		ioctl(0, TIOCSETD, (char *)&odisc);
243 	exit(0);
244 }
245 
246 /*
247  * Muck with user ID's.  We are setuid to the owner of the lock
248  * directory when we start.  user_uid() reverses real and effective
249  * ID's after startup, to run with the user's permissions.
250  * daemon_uid() switches back to the privileged uid for unlocking.
251  * Finally, to avoid running a shell with the wrong real uid,
252  * shell_uid() sets real and effective uid's to the user's real ID.
253  */
254 static int uidswapped;
255 
256 user_uid()
257 {
258 	if (uidswapped == 0) {
259 		seteuid(uid);
260 		uidswapped = 1;
261 	}
262 }
263 
264 daemon_uid()
265 {
266 
267 	if (uidswapped) {
268 		seteuid(euid);
269 		uidswapped = 0;
270 	}
271 }
272 
273 shell_uid()
274 {
275 	seteuid(uid);
276 }
277 
278 /*
279  * put the controlling keyboard into raw mode
280  */
281 raw()
282 {
283 	tcsetattr(0, TCSADRAIN, &term);
284 }
285 
286 
287 /*
288  * return keyboard to normal mode
289  */
290 unraw()
291 {
292 	tcsetattr(0, TCSADRAIN, &defterm);
293 }
294 
295 static	jmp_buf promptbuf;
296 
297 /*
298  * Print string ``s'', then read a string
299  *  in from the terminal.  Handles signals & allows use of
300  *  normal erase and kill characters.
301  */
302 prompt(s, p)
303 	char *s;
304 	register char *p;
305 {
306 	register int c;
307 	register char *b = p;
308 	sig_t oint, oquit;
309 
310 	stoprompt = 0;
311 	oint = signal(SIGINT, intprompt);
312 	oquit = signal(SIGQUIT, SIG_IGN);
313 	unraw();
314 	printf("%s", s);
315 	if (setjmp(promptbuf) == 0)
316 		while ((c = getchar()) != -1 && (*p = c) != '\n')
317 			p++;
318 	*p = '\0';
319 
320 	raw();
321 	(void)signal(SIGINT, oint);
322 	(void)signal(SIGQUIT, oquit);
323 	return (stoprompt || p == b);
324 }
325 
326 /*
327  * Interrupt service routine during prompting
328  */
329 void
330 intprompt()
331 {
332 
333 	(void)signal(SIGINT, SIG_IGN);
334 	stoprompt = 1;
335 	printf("\r\n");
336 	longjmp(promptbuf, 1);
337 }
338 
339 /*
340  * ****TIPIN   TIPIN****
341  */
342 tipin()
343 {
344 	char gch, bol = 1;
345 
346 	/*
347 	 * Kinda klugey here...
348 	 *   check for scripting being turned on from the .tiprc file,
349 	 *   but be careful about just using setscript(), as we may
350 	 *   send a SIGEMT before tipout has a chance to set up catching
351 	 *   it; so wait a second, then setscript()
352 	 */
353 	if (boolean(value(SCRIPT))) {
354 		sleep(1);
355 		setscript();
356 	}
357 
358 	while (1) {
359 		gch = getchar()&STRIP_PAR;
360 		if ((gch == character(value(ESCAPE))) && bol) {
361 			if (!(gch = escape()))
362 				continue;
363 		} else if (!cumode && gch == character(value(RAISECHAR))) {
364 			setboolean(value(RAISE), !boolean(value(RAISE)));
365 			continue;
366 		} else if (gch == '\r') {
367 			bol = 1;
368 			pwrite(FD, &gch, 1);
369 			if (boolean(value(HALFDUPLEX)))
370 				printf("\r\n");
371 			continue;
372 		} else if (!cumode && gch == character(value(FORCE)))
373 			gch = getchar()&STRIP_PAR;
374 		bol = any(gch, value(EOL));
375 		if (boolean(value(RAISE)) && islower(gch))
376 			gch = toupper(gch);
377 		pwrite(FD, &gch, 1);
378 		if (boolean(value(HALFDUPLEX)))
379 			printf("%c", gch);
380 	}
381 }
382 
383 extern esctable_t etable[];
384 
385 /*
386  * Escape handler --
387  *  called on recognition of ``escapec'' at the beginning of a line
388  */
389 escape()
390 {
391 	register char gch;
392 	register esctable_t *p;
393 	char c = character(value(ESCAPE));
394 
395 	gch = (getchar()&STRIP_PAR);
396 	for (p = etable; p->e_char; p++)
397 		if (p->e_char == gch) {
398 			if ((p->e_flags&PRIV) && uid)
399 				continue;
400 			printf("%s", ctrl(c));
401 			(*p->e_func)(gch);
402 			return (0);
403 		}
404 	/* ESCAPE ESCAPE forces ESCAPE */
405 	if (c != gch)
406 		pwrite(FD, &c, 1);
407 	return (gch);
408 }
409 
410 speed(n)
411 	int n;
412 {
413 	register int *p;
414 
415 	for (p = rates; *p != -1;  p++)
416 		if (*p == n)
417 			return n;
418 	return 0;
419 }
420 
421 any(c, p)
422 	register char c, *p;
423 {
424 	while (p && *p)
425 		if (*p++ == c)
426 			return (1);
427 	return (0);
428 }
429 
430 size(s)
431 	register char	*s;
432 {
433 	register int i = 0;
434 
435 	while (s && *s++)
436 		i++;
437 	return (i);
438 }
439 
440 char *
441 interp(s)
442 	register char *s;
443 {
444 	static char buf[256];
445 	register char *p = buf, c, *q;
446 
447 	while (c = *s++) {
448 		for (q = "\nn\rr\tt\ff\033E\bb"; *q; q++)
449 			if (*q++ == c) {
450 				*p++ = '\\'; *p++ = *q;
451 				goto next;
452 			}
453 		if (c < 040) {
454 			*p++ = '^'; *p++ = c + 'A'-1;
455 		} else if (c == 0177) {
456 			*p++ = '^'; *p++ = '?';
457 		} else
458 			*p++ = c;
459 	next:
460 		;
461 	}
462 	*p = '\0';
463 	return (buf);
464 }
465 
466 char *
467 ctrl(c)
468 	char c;
469 {
470 	static char s[3];
471 
472 	if (c < 040 || c == 0177) {
473 		s[0] = '^';
474 		s[1] = c == 0177 ? '?' : c+'A'-1;
475 		s[2] = '\0';
476 	} else {
477 		s[0] = c;
478 		s[1] = '\0';
479 	}
480 	return (s);
481 }
482 
483 /*
484  * Help command
485  */
486 help(c)
487 	char c;
488 {
489 	register esctable_t *p;
490 
491 	printf("%c\r\n", c);
492 	for (p = etable; p->e_char; p++) {
493 		if ((p->e_flags&PRIV) && uid)
494 			continue;
495 		printf("%2s", ctrl(character(value(ESCAPE))));
496 		printf("%-2s %c   %s\r\n", ctrl(p->e_char),
497 			p->e_flags&EXP ? '*': ' ', p->e_help);
498 	}
499 }
500 
501 /*
502  * Set up the "remote" tty's state
503  */
504 ttysetup(speed)
505 	int speed;
506 {
507 	struct termios	cntrl;
508 
509 	tcgetattr(FD, &cntrl);
510 	cfsetospeed(&cntrl, speed);
511 	cfsetispeed(&cntrl, speed);
512 	cntrl.c_cflag &= ~(CSIZE|PARENB);
513 	cntrl.c_cflag |= CS8;
514 	if (DC)
515 		cntrl.c_cflag |= CLOCAL;
516 	cntrl.c_iflag &= ~(ISTRIP|ICRNL);
517 	cntrl.c_oflag &= ~OPOST;
518 	cntrl.c_lflag &= ~(ICANON|ISIG|IEXTEN|ECHO);
519 	cntrl.c_cc[VMIN] = 1;
520 	cntrl.c_cc[VTIME] = 0;
521 	if (boolean(value(TAND)))
522 		cntrl.c_iflag |= IXOFF;
523 	tcsetattr(FD, TCSAFLUSH, &cntrl);
524 }
525 
526 /*
527  * Return "simple" name from a file name,
528  * strip leading directories.
529  */
530 char *
531 sname(s)
532 	register char *s;
533 {
534 	register char *p = s;
535 
536 	while (*s)
537 		if (*s++ == '/')
538 			p = s;
539 	return (p);
540 }
541 
542 static char partab[0200];
543 
544 /*
545  * Do a write to the remote machine with the correct parity.
546  * We are doing 8 bit wide output, so we just generate a character
547  * with the right parity and output it.
548  */
549 pwrite(fd, buf, n)
550 	int fd;
551 	char *buf;
552 	register int n;
553 {
554 	register int i;
555 	register char *bp;
556 	extern int errno;
557 
558 	bp = buf;
559 	if (bits8 == 0)
560 		for (i = 0; i < n; i++) {
561 			*bp = partab[(*bp) & 0177];
562 			bp++;
563 		}
564 	if (write(fd, buf, n) < 0) {
565 		if (errno == EIO)
566 			tipabort("Lost carrier.");
567 		/* this is questionable */
568 		perror("write");
569 	}
570 }
571 
572 /*
573  * Build a parity table with appropriate high-order bit.
574  */
575 setparity(defparity)
576 	char *defparity;
577 {
578 	register int i, flip, clr, set;
579 	char *parity;
580 	extern unsigned char evenpartab[];
581 
582 	if (value(PARITY) == NOSTR)
583 		value(PARITY) = defparity;
584 	parity = value(PARITY);
585 	if (equal(parity, "none")) {
586 		bits8 = 1;
587 		return;
588 	}
589 	bits8 = 0;
590 	flip = 0;
591 	clr = 0377;
592 	set = 0;
593 	if (equal(parity, "odd"))
594 		flip = 0200;			/* reverse bit 7 */
595 	else if (equal(parity, "zero"))
596 		clr = 0177;			/* turn off bit 7 */
597 	else if (equal(parity, "one"))
598 		set = 0200;			/* turn on bit 7 */
599 	else if (!equal(parity, "even")) {
600 		(void) fprintf(stderr, "%s: unknown parity value\r\n", parity);
601 		(void) fflush(stderr);
602 	}
603 	for (i = 0; i < 0200; i++)
604 		partab[i] = (evenpartab[i] ^ flip | set) & clr;
605 }
606