xref: /netbsd-src/usr.bin/tip/tip.c (revision 0b9f50897e9a9c6709320fafb4c3787fddcc0a45)
1 /*
2  * Copyright (c) 1983 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 char copyright[] =
36 "@(#) Copyright (c) 1983 The Regents of the University of California.\n\
37  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 /*static char sccsid[] = "from: @(#)tip.c	5.15 (Berkeley) 2/4/91";*/
42 static char rcsid[] = "$Id: tip.c,v 1.4 1993/08/01 18:06:35 mycroft Exp $";
43 #endif /* not lint */
44 
45 /*
46  * tip - UNIX link to other systems
47  *  tip [-v] [-speed] system-name
48  * or
49  *  cu phone-number [-s speed] [-l line] [-a acu]
50  */
51 #include "tip.h"
52 #include "pathnames.h"
53 
54 /*
55  * Baud rate mapping table
56  */
57 int bauds[] = {
58 	0, 50, 75, 110, 134, 150, 200, 300, 600,
59 	1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200, -1
60 };
61 
62 int	disc = OTTYDISC;		/* tip normally runs this way */
63 void	intprompt();
64 void	timeout();
65 void	cleanup();
66 char	*sname();
67 char	PNbuf[256];			/* This limits the size of a number */
68 
69 main(argc, argv)
70 	char *argv[];
71 {
72 	char *system = NOSTR;
73 	register int i;
74 	register char *p;
75 	char sbuf[12];
76 
77 	gid = getgid();
78 	egid = getegid();
79 	uid = getuid();
80 	euid = geteuid();
81 	if (equal(sname(argv[0]), "cu")) {
82 		cumode = 1;
83 		cumain(argc, argv);
84 		goto cucommon;
85 	}
86 
87 	if (argc > 4) {
88 		fprintf(stderr, "usage: tip [-v] [-speed] [system-name]\n");
89 		exit(1);
90 	}
91 	if (!isatty(0)) {
92 		fprintf(stderr, "tip: must be interactive\n");
93 		exit(1);
94 	}
95 
96 	for (; argc > 1; argv++, argc--) {
97 		if (argv[1][0] != '-')
98 			system = argv[1];
99 		else switch (argv[1][1]) {
100 
101 		case 'v':
102 			vflag++;
103 			break;
104 
105 		case '0': case '1': case '2': case '3': case '4':
106 		case '5': case '6': case '7': case '8': case '9':
107 			BR = atoi(&argv[1][1]);
108 			break;
109 
110 		default:
111 			fprintf(stderr, "tip: %s, unknown option\n", argv[1]);
112 			break;
113 		}
114 	}
115 
116 	if (system == NOSTR)
117 		goto notnumber;
118 	if (isalpha(*system))
119 		goto notnumber;
120 	/*
121 	 * System name is really a phone number...
122 	 * Copy the number then stomp on the original (in case the number
123 	 *	is private, we don't want 'ps' or 'w' to find it).
124 	 */
125 	if (strlen(system) > sizeof PNbuf - 1) {
126 		fprintf(stderr, "tip: phone number too long (max = %d bytes)\n",
127 			sizeof PNbuf - 1);
128 		exit(1);
129 	}
130 	strncpy( PNbuf, system, sizeof PNbuf - 1 );
131 	for (p = system; *p; p++)
132 		*p = '\0';
133 	PN = PNbuf;
134 	(void)sprintf(sbuf, "tip%d", BR);
135 	system = sbuf;
136 
137 notnumber:
138 	(void)signal(SIGINT, cleanup);
139 	(void)signal(SIGQUIT, cleanup);
140 	(void)signal(SIGHUP, cleanup);
141 	(void)signal(SIGTERM, cleanup);
142 
143 	if ((i = hunt(system)) == 0) {
144 		printf("all ports busy\n");
145 		exit(3);
146 	}
147 	if (i == -1) {
148 		printf("link down\n");
149 		(void)uu_unlock(uucplock);
150 		exit(3);
151 	}
152 	setbuf(stdout, NULL);
153 	loginit();
154 
155 	/*
156 	 * Now that we have the logfile and the ACU open
157 	 *  return to the real uid and gid.  These things will
158 	 *  be closed on exit.  Swap real and effective uid's
159 	 *  so we can get the original permissions back
160 	 *  for removing the uucp lock.
161 	 */
162 	user_uid();
163 
164 	/*
165 	 * Kludge, their's no easy way to get the initialization
166 	 *   in the right order, so force it here
167 	 */
168 	if ((PH = getenv("PHONES")) == NOSTR)
169 		PH = _PATH_PHONES;
170 	vinit();				/* init variables */
171 	setparity("even");			/* set the parity table */
172 	if ((i = speed(number(value(BAUDRATE)))) == NULL) {
173 		printf("tip: bad baud rate %d\n", number(value(BAUDRATE)));
174 		daemon_uid();
175 		(void)uu_unlock(uucplock);
176 		exit(3);
177 	}
178 
179 	/*
180 	 * Hardwired connections require the
181 	 *  line speed set before they make any transmissions
182 	 *  (this is particularly true of things like a DF03-AC)
183 	 */
184 	if (HW)
185 		ttysetup(i);
186 	if (p = connect()) {
187 		printf("\07%s\n[EOT]\n", p);
188 		daemon_uid();
189 		(void)uu_unlock(uucplock);
190 		exit(1);
191 	}
192 	if (!HW)
193 		ttysetup(i);
194 cucommon:
195 	/*
196 	 * From here down the code is shared with
197 	 * the "cu" version of tip.
198 	 */
199 
200 	ioctl(0, TIOCGETP, (char *)&defarg);
201 	ioctl(0, TIOCGETC, (char *)&defchars);
202 	ioctl(0, TIOCGLTC, (char *)&deflchars);
203 	ioctl(0, TIOCGETD, (char *)&odisc);
204 	arg = defarg;
205 	arg.sg_flags = ANYP | CBREAK;
206 	tchars = defchars;
207 	tchars.t_intrc = tchars.t_quitc = -1;
208 	ltchars = deflchars;
209 	ltchars.t_suspc = ltchars.t_dsuspc = ltchars.t_flushc
210 		= ltchars.t_lnextc = -1;
211 	raw();
212 
213 	pipe(fildes); pipe(repdes);
214 	(void)signal(SIGALRM, timeout);
215 
216 	/*
217 	 * Everything's set up now:
218 	 *	connection established (hardwired or dialup)
219 	 *	line conditioned (baud rate, mode, etc.)
220 	 *	internal data structures (variables)
221 	 * so, fork one process for local side and one for remote.
222 	 */
223 	printf(cumode ? "Connected\r\n" : "\07connected\r\n");
224 	if (pid = fork())
225 		tipin();
226 	else
227 		tipout();
228 	/*NOTREACHED*/
229 }
230 
231 void
232 cleanup()
233 {
234 
235 	daemon_uid();
236 	(void)uu_unlock(uucplock);
237 	if (odisc)
238 		ioctl(0, TIOCSETD, (char *)&odisc);
239 	exit(0);
240 }
241 
242 /*
243  * Muck with user ID's.  We are setuid to the owner of the lock
244  * directory when we start.  user_uid() reverses real and effective
245  * ID's after startup, to run with the user's permissions.
246  * daemon_uid() switches back to the privileged uid for unlocking.
247  * Finally, to avoid running a shell with the wrong real uid,
248  * shell_uid() sets real and effective uid's to the user's real ID.
249  */
250 static int uidswapped;
251 
252 user_uid()
253 {
254 	if (uidswapped == 0) {
255 		setregid(egid, gid);
256 		setreuid(euid, uid);
257 		uidswapped = 1;
258 	}
259 }
260 
261 daemon_uid()
262 {
263 
264 	if (uidswapped) {
265 		setreuid(uid, euid);
266 		setregid(gid, egid);
267 		uidswapped = 0;
268 	}
269 }
270 
271 shell_uid()
272 {
273 
274 	setreuid(uid, uid);
275 	setregid(gid, gid);
276 }
277 
278 /*
279  * put the controlling keyboard into raw mode
280  */
281 raw()
282 {
283 
284 	ioctl(0, TIOCSETP, &arg);
285 	ioctl(0, TIOCSETC, &tchars);
286 	ioctl(0, TIOCSLTC, &ltchars);
287 	ioctl(0, TIOCSETD, (char *)&disc);
288 }
289 
290 
291 /*
292  * return keyboard to normal mode
293  */
294 unraw()
295 {
296 
297 	ioctl(0, TIOCSETD, (char *)&odisc);
298 	ioctl(0, TIOCSETP, (char *)&defarg);
299 	ioctl(0, TIOCSETC, (char *)&defchars);
300 	ioctl(0, TIOCSLTC, (char *)&deflchars);
301 }
302 
303 static	jmp_buf promptbuf;
304 
305 /*
306  * Print string ``s'', then read a string
307  *  in from the terminal.  Handles signals & allows use of
308  *  normal erase and kill characters.
309  */
310 prompt(s, p)
311 	char *s;
312 	register char *p;
313 {
314 	register char *b = p;
315 	sig_t oint, oquit;
316 
317 	stoprompt = 0;
318 	oint = signal(SIGINT, intprompt);
319 	oquit = signal(SIGQUIT, SIG_IGN);
320 	unraw();
321 	printf("%s", s);
322 	if (setjmp(promptbuf) == 0)
323 		while ((*p = getchar()) != EOF && *p != '\n')
324 			p++;
325 	*p = '\0';
326 
327 	raw();
328 	(void)signal(SIGINT, oint);
329 	(void)signal(SIGQUIT, oquit);
330 	return (stoprompt || p == b);
331 }
332 
333 /*
334  * Interrupt service routine during prompting
335  */
336 void
337 intprompt()
338 {
339 
340 	(void)signal(SIGINT, SIG_IGN);
341 	stoprompt = 1;
342 	printf("\r\n");
343 	longjmp(promptbuf, 1);
344 }
345 
346 /*
347  * ****TIPIN   TIPIN****
348  */
349 tipin()
350 {
351 	char gch, bol = 1;
352 
353 	/*
354 	 * Kinda klugey here...
355 	 *   check for scripting being turned on from the .tiprc file,
356 	 *   but be careful about just using setscript(), as we may
357 	 *   send a SIGEMT before tipout has a chance to set up catching
358 	 *   it; so wait a second, then setscript()
359 	 */
360 	if (boolean(value(SCRIPT))) {
361 		sleep(1);
362 		setscript();
363 	}
364 
365 	while (1) {
366 		gch = getchar()&0177;
367 		if ((gch == character(value(ESCAPE))) && bol) {
368 			if (!(gch = escape()))
369 				continue;
370 		} else if (!cumode && gch == character(value(RAISECHAR))) {
371 			boolean(value(RAISE)) = !boolean(value(RAISE));
372 			continue;
373 		} else if (gch == '\r') {
374 			bol = 1;
375 			pwrite(FD, &gch, 1);
376 			if (boolean(value(HALFDUPLEX)))
377 				printf("\r\n");
378 			continue;
379 		} else if (!cumode && gch == character(value(FORCE)))
380 			gch = getchar()&0177;
381 		bol = any(gch, value(EOL));
382 		if (boolean(value(RAISE)) && islower(gch))
383 			gch = toupper(gch);
384 		pwrite(FD, &gch, 1);
385 		if (boolean(value(HALFDUPLEX)))
386 			printf("%c", gch);
387 	}
388 }
389 
390 /*
391  * Escape handler --
392  *  called on recognition of ``escapec'' at the beginning of a line
393  */
394 escape()
395 {
396 	register char gch;
397 	register esctable_t *p;
398 	char c = character(value(ESCAPE));
399 	extern esctable_t etable[];
400 
401 	gch = (getchar()&0177);
402 	for (p = etable; p->e_char; p++)
403 		if (p->e_char == gch) {
404 			if ((p->e_flags&PRIV) && uid)
405 				continue;
406 			printf("%s", ctrl(c));
407 			(*p->e_func)(gch);
408 			return (0);
409 		}
410 	/* ESCAPE ESCAPE forces ESCAPE */
411 	if (c != gch)
412 		pwrite(FD, &c, 1);
413 	return (gch);
414 }
415 
416 speed(n)
417 	int n;
418 {
419 	register int *p;
420 
421 	for (p = bauds; *p != -1;  p++)
422 		if (*p == n)
423 			return (p - bauds);
424 	return (NULL);
425 }
426 
427 any(c, p)
428 	register char c, *p;
429 {
430 	while (p && *p)
431 		if (*p++ == c)
432 			return (1);
433 	return (0);
434 }
435 
436 size(s)
437 	register char	*s;
438 {
439 	register int i = 0;
440 
441 	while (s && *s++)
442 		i++;
443 	return (i);
444 }
445 
446 char *
447 interp(s)
448 	register char *s;
449 {
450 	static char buf[256];
451 	register char *p = buf, c, *q;
452 
453 	while (c = *s++) {
454 		for (q = "\nn\rr\tt\ff\033E\bb"; *q; q++)
455 			if (*q++ == c) {
456 				*p++ = '\\'; *p++ = *q;
457 				goto next;
458 			}
459 		if (c < 040) {
460 			*p++ = '^'; *p++ = c + 'A'-1;
461 		} else if (c == 0177) {
462 			*p++ = '^'; *p++ = '?';
463 		} else
464 			*p++ = c;
465 	next:
466 		;
467 	}
468 	*p = '\0';
469 	return (buf);
470 }
471 
472 char *
473 ctrl(c)
474 	char c;
475 {
476 	static char s[3];
477 
478 	if (c < 040 || c == 0177) {
479 		s[0] = '^';
480 		s[1] = c == 0177 ? '?' : c+'A'-1;
481 		s[2] = '\0';
482 	} else {
483 		s[0] = c;
484 		s[1] = '\0';
485 	}
486 	return (s);
487 }
488 
489 /*
490  * Help command
491  */
492 help(c)
493 	char c;
494 {
495 	register esctable_t *p;
496 	extern esctable_t etable[];
497 
498 	printf("%c\r\n", c);
499 	for (p = etable; p->e_char; p++) {
500 		if ((p->e_flags&PRIV) && uid)
501 			continue;
502 		printf("%2s", ctrl(character(value(ESCAPE))));
503 		printf("%-2s %c   %s\r\n", ctrl(p->e_char),
504 			p->e_flags&EXP ? '*': ' ', p->e_help);
505 	}
506 }
507 
508 /*
509  * Set up the "remote" tty's state
510  */
511 ttysetup(speed)
512 	int speed;
513 {
514 	unsigned bits = LDECCTQ;
515 
516 	arg.sg_ispeed = arg.sg_ospeed = speed;
517 	arg.sg_flags = RAW;
518 	if (boolean(value(TAND)))
519 		arg.sg_flags |= TANDEM;
520 	ioctl(FD, TIOCSETP, (char *)&arg);
521 	ioctl(FD, TIOCLBIS, (char *)&bits);
522 }
523 
524 /*
525  * Return "simple" name from a file name,
526  * strip leading directories.
527  */
528 char *
529 sname(s)
530 	register char *s;
531 {
532 	register char *p = s;
533 
534 	while (*s)
535 		if (*s++ == '/')
536 			p = s;
537 	return (p);
538 }
539 
540 static char partab[0200];
541 static int bits8;
542 
543 /*
544  * Do a write to the remote machine with the correct parity.
545  * We are doing 8 bit wide output, so we just generate a character
546  * with the right parity and output it.
547  */
548 pwrite(fd, buf, n)
549 	int fd;
550 	char *buf;
551 	register int n;
552 {
553 	register int i;
554 	register char *bp;
555 	extern int errno;
556 
557 	bp = buf;
558 	if (bits8 == 0) {
559 		static char *mbp; static sz;
560 
561 		if (mbp == 0 || n > sz) {
562 			if (mbp)
563 				free(mbp);
564 			mbp = (char *) malloc(n);
565 			sz = n;
566 		}
567 
568 		bp = mbp;
569 		for (i = 0; i < n; i++)
570 			*bp++ = partab[*buf++ & 0177];
571 		bp = mbp;
572 	}
573 	if (write(fd, bp, n) < 0) {
574 		if (errno == EIO)
575 			tipabort("Lost carrier.");
576 		/* this is questionable */
577 		perror("write");
578 	}
579 }
580 
581 /*
582  * Build a parity table with appropriate high-order bit.
583  */
584 setparity(defparity)
585 	char *defparity;
586 {
587 	register int i, flip, clr, set;
588 	char *parity;
589 	extern char evenpartab[];
590 
591 	if (value(PARITY) == NOSTR)
592 		value(PARITY) = defparity;
593 	parity = value(PARITY);
594 	if (equal(parity, "none")) {
595 		bits8 = 1;
596 		return;
597 	}
598 	bits8 = 0;
599 	flip = 0;
600 	clr = 0377;
601 	set = 0;
602 	if (equal(parity, "odd"))
603 		flip = 0200;			/* reverse bit 7 */
604 	else if (equal(parity, "zero"))
605 		clr = 0177;			/* turn off bit 7 */
606 	else if (equal(parity, "one"))
607 		set = 0200;			/* turn on bit 7 */
608 	else if (!equal(parity, "even")) {
609 		(void) fprintf(stderr, "%s: unknown parity value\r\n", parity);
610 		(void) fflush(stderr);
611 	}
612 	for (i = 0; i < 0200; i++)
613 		partab[i] = evenpartab[i] ^ flip | set & clr;
614 }
615