xref: /netbsd-src/usr.bin/tip/tip.c (revision 93f9db1b75d415b78f73ed629beeb86235153473)
1 /*	$NetBSD: tip.c,v 1.21 1998/07/12 09:59:30 mrg 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 #include <sys/cdefs.h>
37 #ifndef lint
38 __COPYRIGHT("@(#) 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 __RCSID("$NetBSD: tip.c,v 1.21 1998/07/12 09:59:30 mrg 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 
68 int	escape __P((void));
69 int	main __P((int, char **));
70 void	intprompt __P((int));
71 void	tipin __P((void));
72 
73 char	PNbuf[256];			/* This limits the size of a number */
74 
75 int
76 main(argc, argv)
77 	int argc;
78 	char *argv[];
79 {
80 	char *system = NULL;
81 	int i;
82 	char *p;
83 	char sbuf[12];
84 	int fcarg;
85 
86 	gid = getgid();
87 	egid = getegid();
88 	uid = getuid();
89 	euid = geteuid();
90 	if (equal(basename(argv[0]), "cu")) {
91 		cumode = 1;
92 		cumain(argc, argv);
93 		goto cucommon;
94 	}
95 
96 	if (argc > 4) {
97 		fprintf(stderr, "usage: tip [-v] [-speed] [system-name]\n");
98 		exit(1);
99 	}
100 	if (!isatty(0)) {
101 		fprintf(stderr, "tip: must be interactive\n");
102 		exit(1);
103 	}
104 
105 	for (; argc > 1; argv++, argc--) {
106 		if (argv[1][0] != '-')
107 			system = argv[1];
108 		else switch (argv[1][1]) {
109 
110 		case 'v':
111 			vflag++;
112 			break;
113 
114 		case '0': case '1': case '2': case '3': case '4':
115 		case '5': case '6': case '7': case '8': case '9':
116 			BR = atoi(&argv[1][1]);
117 			break;
118 
119 		default:
120 			fprintf(stderr, "tip: %s, unknown option\n", argv[1]);
121 			break;
122 		}
123 	}
124 
125 	if (system == NULL)
126 		goto notnumber;
127 	if (isalpha(*system))
128 		goto notnumber;
129 	/*
130 	 * System name is really a phone number...
131 	 * Copy the number then stomp on the original (in case the number
132 	 *	is private, we don't want 'ps' or 'w' to find it).
133 	 */
134 	if (strlen(system) > sizeof PNbuf - 1) {
135 		fprintf(stderr, "tip: phone number too long (max = %d bytes)\n",
136 			(int)sizeof(PNbuf) - 1);
137 		exit(1);
138 	}
139 	strncpy(PNbuf, system, sizeof PNbuf - 1);
140 	PNbuf[sizeof PNbuf - 1] = '\0';
141 	for (p = system; *p; p++)
142 		*p = '\0';
143 	PN = PNbuf;
144 	(void)snprintf(sbuf, sizeof sbuf, "tip%d", (int)BR);
145 	system = sbuf;
146 
147 notnumber:
148 	(void)signal(SIGINT, cleanup);
149 	(void)signal(SIGQUIT, cleanup);
150 	(void)signal(SIGHUP, cleanup);
151 	(void)signal(SIGTERM, cleanup);
152 
153 	if ((i = hunt(system)) == 0) {
154 		printf("all ports busy\n");
155 		exit(3);
156 	}
157 	if (i == -1) {
158 		printf("link down\n");
159 		(void)uu_unlock(uucplock);
160 		exit(3);
161 	}
162 	setbuf(stdout, NULL);
163 	loginit();
164 
165 	/*
166 	 * Now that we have the logfile and the ACU open
167 	 *  return to the real uid and gid.  These things will
168 	 *  be closed on exit.  Swap real and effective uid's
169 	 *  so we can get the original permissions back
170 	 *  for removing the uucp lock.
171 	 */
172 	user_uid();
173 
174 	/*
175 	 * Kludge, their's no easy way to get the initialization
176 	 *   in the right order, so force it here
177 	 */
178 	if ((PH = getenv("PHONES")) == NULL)
179 		PH = _PATH_PHONES;
180 	vinit();				/* init variables */
181 	setparity("even");			/* set the parity table */
182 	if ((i = speed(number(value(BAUDRATE)))) == 0) {
183 		printf("tip: bad baud rate %d\n", (int)number(value(BAUDRATE)));
184 		daemon_uid();
185 		(void)uu_unlock(uucplock);
186 		exit(3);
187 	}
188 
189 	/*
190 	 * Hardwired connections require the
191 	 *  line speed set before they make any transmissions
192 	 *  (this is particularly true of things like a DF03-AC)
193 	 */
194 	if (HW)
195 		ttysetup(i);
196 	if ((p = connect()) != NULL) {
197 		printf("\07%s\n[EOT]\n", p);
198 		daemon_uid();
199 		(void)uu_unlock(uucplock);
200 		exit(1);
201 	}
202 	if (!HW)
203 		ttysetup(i);
204 
205 	/*
206 	 * Direct connections with no carrier require using O_NONBLOCK on
207 	 * open, but we don't want to keep O_NONBLOCK after open because it
208 	 * will cause busy waits.
209 	 */
210 	if (DC &&
211 	    ((fcarg = fcntl(FD, F_GETFL, 0)) < 0 ||
212 	     fcntl(FD, F_SETFL, fcarg & ~O_NONBLOCK) < 0)) {
213 		printf("tip: can't clear O_NONBLOCK: %s", strerror (errno));
214 		daemon_uid();
215 		(void)uu_unlock(uucplock);
216 		exit(1);
217 	}
218 
219 cucommon:
220 	/*
221 	 * From here down the code is shared with
222 	 * the "cu" version of tip.
223 	 */
224 
225 	tcgetattr(0, &defterm);
226 	term = defterm;
227 	term.c_lflag &= ~(ICANON|IEXTEN|ECHO);
228 	term.c_iflag &= ~(INPCK|ICRNL);
229 	term.c_oflag &= ~OPOST;
230 	term.c_cc[VMIN] = 1;
231 	term.c_cc[VTIME] = 0;
232 	defchars = term;
233 	term.c_cc[VINTR] = term.c_cc[VQUIT] = term.c_cc[VSUSP] =
234 		term.c_cc[VDSUSP] = term.c_cc[VDISCARD] =
235 	 	term.c_cc[VLNEXT] = _POSIX_VDISABLE;
236 	raw();
237 
238 	pipe(fildes); pipe(repdes);
239 	(void)signal(SIGALRM, alrmtimeout);
240 
241 	/*
242 	 * Everything's set up now:
243 	 *	connection established (hardwired or dialup)
244 	 *	line conditioned (baud rate, mode, etc.)
245 	 *	internal data structures (variables)
246 	 * so, fork one process for local side and one for remote.
247 	 */
248 	printf(cumode ? "Connected\r\n" : "\07connected\r\n");
249 	switch (pid = fork()) {
250 	default:
251 		tipin();
252 		break;
253 	case 0:
254 		tipout();
255 		break;
256 	case -1:
257 		err(1, "can't fork");
258 	}
259 	/*NOTREACHED*/
260 	exit(0);	/* XXX: pacify gcc */
261 }
262 
263 void
264 cleanup(dummy)
265 	int dummy;
266 {
267 
268 	daemon_uid();
269 	(void)uu_unlock(uucplock);
270 	if (odisc)
271 		ioctl(0, TIOCSETD, (char *)&odisc);
272 	exit(0);
273 }
274 
275 /*
276  * Muck with user ID's.  We are setuid to the owner of the lock
277  * directory when we start.  user_uid() reverses real and effective
278  * ID's after startup, to run with the user's permissions.
279  * daemon_uid() switches back to the privileged uid for unlocking.
280  * Finally, to avoid running a shell with the wrong real uid,
281  * shell_uid() sets real and effective uid's to the user's real ID.
282  */
283 static int uidswapped;
284 
285 void
286 user_uid()
287 {
288 
289 	if (uidswapped == 0) {
290 		seteuid(uid);
291 		uidswapped = 1;
292 	}
293 }
294 
295 void
296 daemon_uid()
297 {
298 
299 	if (uidswapped) {
300 		seteuid(euid);
301 		uidswapped = 0;
302 	}
303 }
304 
305 void
306 shell_uid()
307 {
308 
309 	seteuid(uid);
310 }
311 
312 /*
313  * put the controlling keyboard into raw mode
314  */
315 void
316 raw()
317 {
318 
319 	tcsetattr(0, TCSADRAIN, &term);
320 }
321 
322 
323 /*
324  * return keyboard to normal mode
325  */
326 void
327 unraw()
328 {
329 
330 	tcsetattr(0, TCSADRAIN, &defterm);
331 }
332 
333 static	jmp_buf promptbuf;
334 
335 /*
336  * Print string ``s'', then read a string
337  *  in from the terminal.  Handles signals & allows use of
338  *  normal erase and kill characters.
339  */
340 int
341 prompt(s, p, l)
342 	char *s;
343 	char *p;
344 	size_t l;
345 {
346 	int c;
347 	char *b = p;
348 	sig_t oint, oquit;
349 
350 #if __GNUC__		/* XXX: pacify gcc */
351 	(void)&p;
352 #endif
353 
354 	stoprompt = 0;
355 	oint = signal(SIGINT, intprompt);
356 	oquit = signal(SIGQUIT, SIG_IGN);
357 	unraw();
358 	printf("%s", s);
359 	if (setjmp(promptbuf) == 0)
360 		while ((c = getchar()) != -1 && (*p = c) != '\n' &&
361 		    b + l > p)
362 			p++;
363 	*p = '\0';
364 
365 	raw();
366 	(void)signal(SIGINT, oint);
367 	(void)signal(SIGQUIT, oquit);
368 	return (stoprompt || p == b);
369 }
370 
371 /*
372  * Interrupt service routine during prompting
373  */
374 void
375 intprompt(dummy)
376 	int dummy;
377 {
378 
379 	(void)signal(SIGINT, SIG_IGN);
380 	stoprompt = 1;
381 	printf("\r\n");
382 	longjmp(promptbuf, 1);
383 }
384 
385 /*
386  * ****TIPIN   TIPIN****
387  */
388 void
389 tipin()
390 {
391 	char gch, bol = 1;
392 
393 	/*
394 	 * Kinda klugey here...
395 	 *   check for scripting being turned on from the .tiprc file,
396 	 *   but be careful about just using setscript(), as we may
397 	 *   send a SIGEMT before tipout has a chance to set up catching
398 	 *   it; so wait a second, then setscript()
399 	 */
400 	if (boolean(value(SCRIPT))) {
401 		sleep(1);
402 		setscript();
403 	}
404 
405 	while (1) {
406 		gch = getchar()&STRIP_PAR;
407 		if ((gch == character(value(ESCAPE))) && bol) {
408 			if (!(gch = escape()))
409 				continue;
410 		} else if (!cumode &&
411 		    gch && gch == character(value(RAISECHAR))) {
412 			setboolean(value(RAISE), !boolean(value(RAISE)));
413 			continue;
414 		} else if (gch == '\r') {
415 			bol = 1;
416 			xpwrite(FD, &gch, 1);
417 			if (boolean(value(HALFDUPLEX)))
418 				printf("\r\n");
419 			continue;
420 		} else if (!cumode && gch && gch == character(value(FORCE)))
421 			gch = getchar()&STRIP_PAR;
422 		bol = any(gch, value(EOL));
423 		if (boolean(value(RAISE)) && islower(gch))
424 			gch = toupper(gch);
425 		xpwrite(FD, &gch, 1);
426 		if (boolean(value(HALFDUPLEX)))
427 			printf("%c", gch);
428 	}
429 }
430 
431 /*
432  * Escape handler --
433  *  called on recognition of ``escapec'' at the beginning of a line
434  */
435 int
436 escape()
437 {
438 	char gch;
439 	esctable_t *p;
440 	char c = character(value(ESCAPE));
441 
442 	gch = (getchar()&STRIP_PAR);
443 	for (p = etable; p->e_char; p++)
444 		if (p->e_char == gch) {
445 			if ((p->e_flags&PRIV) && uid)
446 				continue;
447 			printf("%s", ctrl(c));
448 			(*p->e_func)(gch);
449 			return (0);
450 		}
451 	/* ESCAPE ESCAPE forces ESCAPE */
452 	if (c != gch)
453 		xpwrite(FD, &c, 1);
454 	return (gch);
455 }
456 
457 int
458 speed(n)
459 	int n;
460 {
461 	int *p;
462 
463 	for (p = rates; *p != -1;  p++)
464 		if (*p == n)
465 			return n;
466 	return 0;
467 }
468 
469 int
470 any(c, p)
471 	char c, *p;
472 {
473 
474 	while (p && *p)
475 		if (*p++ == c)
476 			return (1);
477 	return (0);
478 }
479 
480 char *
481 interp(s)
482 	char *s;
483 {
484 	static char buf[256];
485 	char *p = buf, c, *q;
486 
487 	while ((c = *s++) != 0 && buf + sizeof buf - p > 2) {
488 		for (q = "\nn\rr\tt\ff\033E\bb"; *q; q++)
489 			if (*q++ == c) {
490 				*p++ = '\\'; *p++ = *q;
491 				goto next;
492 			}
493 		if (c < 040) {
494 			*p++ = '^'; *p++ = c + 'A'-1;
495 		} else if (c == 0177) {
496 			*p++ = '^'; *p++ = '?';
497 		} else
498 			*p++ = c;
499 	next:
500 		;
501 	}
502 	*p = '\0';
503 	return (buf);
504 }
505 
506 char *
507 ctrl(c)
508 	char c;
509 {
510 	static char s[3];
511 
512 	if (c < 040 || c == 0177) {
513 		s[0] = '^';
514 		s[1] = c == 0177 ? '?' : c+'A'-1;
515 		s[2] = '\0';
516 	} else {
517 		s[0] = c;
518 		s[1] = '\0';
519 	}
520 	return (s);
521 }
522 
523 /*
524  * Help command
525  */
526 void
527 help(c)
528 	char c;
529 {
530 	esctable_t *p;
531 
532 	printf("%c\r\n", c);
533 	for (p = etable; p->e_char; p++) {
534 		if ((p->e_flags&PRIV) && uid)
535 			continue;
536 		printf("%2s", ctrl(character(value(ESCAPE))));
537 		printf("%-2s %c   %s\r\n", ctrl(p->e_char),
538 			p->e_flags&EXP ? '*': ' ', p->e_help);
539 	}
540 }
541 
542 /*
543  * Set up the "remote" tty's state
544  */
545 void
546 ttysetup(speed)
547 	int speed;
548 {
549 	struct termios	cntrl;
550 
551 	tcgetattr(FD, &cntrl);
552 	cfsetospeed(&cntrl, speed);
553 	cfsetispeed(&cntrl, speed);
554 	cntrl.c_cflag &= ~(CSIZE|PARENB);
555 	cntrl.c_cflag |= CS8;
556 	if (DC)
557 		cntrl.c_cflag |= CLOCAL;
558 	cntrl.c_iflag &= ~(ISTRIP|ICRNL);
559 	cntrl.c_oflag &= ~OPOST;
560 	cntrl.c_lflag &= ~(ICANON|ISIG|IEXTEN|ECHO);
561 	cntrl.c_cc[VMIN] = 1;
562 	cntrl.c_cc[VTIME] = 0;
563 	if (boolean(value(TAND)))
564 		cntrl.c_iflag |= IXOFF;
565 	tcsetattr(FD, TCSAFLUSH, &cntrl);
566 }
567 
568 static char partab[0200];
569 
570 /*
571  * Do a write to the remote machine with the correct parity.
572  * We are doing 8 bit wide output, so we just generate a character
573  * with the right parity and output it.
574  */
575 void
576 xpwrite(fd, buf, n)
577 	int fd;
578 	char *buf;
579 	int n;
580 {
581 	int i;
582 	char *bp;
583 
584 	bp = buf;
585 	if (bits8 == 0)
586 		for (i = 0; i < n; i++) {
587 			*bp = partab[(*bp) & 0177];
588 			bp++;
589 		}
590 	if (write(fd, buf, n) < 0) {
591 		if (errno == EIO)
592 			tipabort("Lost carrier.");
593 		/* this is questionable */
594 		perror("write");
595 	}
596 }
597 
598 /*
599  * Build a parity table with appropriate high-order bit.
600  */
601 void
602 setparity(defparity)
603 	char *defparity;
604 {
605 	int i, flip, clr, set;
606 	char *parity;
607 
608 	if (value(PARITY) == NULL || (value(PARITY))[0] == '\0')
609 		value(PARITY) = defparity;
610 	parity = value(PARITY);
611 	if (equal(parity, "none")) {
612 		bits8 = 1;
613 		return;
614 	}
615 	bits8 = 0;
616 	flip = 0;
617 	clr = 0377;
618 	set = 0;
619 	if (equal(parity, "odd"))
620 		flip = 0200;			/* reverse bit 7 */
621 	else if (equal(parity, "zero"))
622 		clr = 0177;			/* turn off bit 7 */
623 	else if (equal(parity, "one"))
624 		set = 0200;			/* turn on bit 7 */
625 	else if (!equal(parity, "even")) {
626 		(void) fprintf(stderr, "%s: unknown parity value\r\n", parity);
627 		(void) fflush(stderr);
628 	}
629 	for (i = 0; i < 0200; i++)
630 		partab[i] = ((evenpartab[i] ^ flip) | set) & clr;
631 }
632