xref: /netbsd/usr.bin/tip/tip.c (revision fda9c6fe)
1 /*	$NetBSD: tip.c,v 1.63 2020/04/23 00:35:14 joerg 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. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #include <ctype.h>
34 #include <libgen.h>
35 
36 #ifndef lint
37 __COPYRIGHT("@(#) Copyright (c) 1983, 1993\
38  The Regents of the University of California.  All rights reserved.");
39 #endif /* not lint */
40 
41 #ifndef lint
42 #if 0
43 static char sccsid[] = "@(#)tip.c	8.1 (Berkeley) 6/6/93";
44 #endif
45 __RCSID("$NetBSD: tip.c,v 1.63 2020/04/23 00:35:14 joerg Exp $");
46 #endif /* not lint */
47 
48 /*
49  * tip - UNIX link to other systems
50  *  tip [-v] [-speed] system-name
51  * or
52  *  cu [options] [phone-number|"dir"]
53  */
54 #include "tip.h"
55 #include "pathnames.h"
56 
57 struct termios	term;
58 struct termios	defterm;
59 struct termios	defchars;
60 
61 FILE	*fscript;
62 
63 int	attndes[2];
64 int	fildes[2];
65 int	repdes[2];
66 int	FD;
67 #ifndef __lint__  /* not used by hayes.c, but used by some other dialers */
68 int	AC;
69 #endif /*__lint__*/
70 int	sfd;
71 int	pid;
72 uid_t	uid, euid;
73 gid_t	gid, egid;
74 int	stop;
75 int	quit;
76 int	stoprompt;
77 int	timedout;
78 int	cumode;
79 int	bits8;
80 #define STRIP_PAR	(bits8 ? 0377 : 0177)
81 
82 char	fname[80];
83 char	copyname[80];
84 char	ccc;
85 
86 int	odisc;
87 int	vflag;
88 
89 char	*DV;
90 char	*EL;
91 char	*CM;
92 char	*IE;
93 char	*OE;
94 char	*CU;
95 char	*AT;
96 char	*PN;
97 char	*DI;
98 char	*PA;
99 
100 char	*PH;
101 char	*RM;
102 char	*HO;
103 
104 long	BR;
105 long	FS;
106 
107 long	DU;
108 long	HW;
109 char	*ES;
110 char	*EX;
111 char	*FO;
112 char	*RC;
113 char	*RE;
114 char	*PR;
115 long	DL;
116 long	CL;
117 long	ET;
118 long	HD;
119 char	DC;
120 
121 __dead static void	tipusage(void);
122 
123 int	escape(void);
124 __dead static void	intprompt(int);
125 __dead static void	tipin(void);
126 
127 char	PNbuf[256];			/* This limits the size of a number */
128 
129 static char path_phones[] = _PATH_PHONES;
130 
131 int
main(int argc,char * argv[])132 main(int argc, char *argv[])
133 {
134 	char *System = NULL;
135 	int c, i;
136 	char *p;
137 	const char *q;
138 	char sbuf[12];
139 	int cmdlineBR;
140 	int fcarg;
141 
142 	setprogname(argv[0]);
143 	gid = getgid();
144 	egid = getegid();
145 	uid = getuid();
146 	euid = geteuid();
147 	if (strcmp(getprogname(), "cu") == 0) {
148 		cumode = 1;
149 		cumain(argc, argv);
150 		goto cucommon;
151 	}
152 
153 	if (argc > 4)
154 		tipusage();
155 
156 	if (!isatty(0))
157 		errx(EXIT_FAILURE, "must be interactive");
158 
159 	cmdlineBR = 0;
160 	while((c = getopt(argc, argv, "v0123456789")) != -1) {
161 		switch(c) {
162 
163 		case 'v':
164 			vflag++;
165 			break;
166 
167 		case '0': case '1': case '2': case '3': case '4':
168 		case '5': case '6': case '7': case '8': case '9':
169 			cmdlineBR = cmdlineBR * 10 + (c - '0');
170 			BR = cmdlineBR;
171 			break;
172 
173 		default:
174 			warnx("%s, unknown option", argv[1]);
175 			break;
176 		}
177 	}
178 
179 	argc -= optind;
180 	argv += optind;
181 
182 	if (argc != 1)
183 		tipusage();
184 	else
185 		System = argv[0];
186 
187 
188 	if (System == NULL)
189 		goto notnumber;
190 	if (isalpha((unsigned char)*System))
191 		goto notnumber;
192 	/*
193 	 * System name is really a phone number...
194 	 * Copy the number then stomp on the original (in case the number
195 	 *	is private, we don't want 'ps' or 'w' to find it).
196 	 */
197 	if (strlen(System) > sizeof PNbuf - 1) {
198 		errx(1, "phone number too long (max = %d bytes)",
199 			(int)sizeof(PNbuf) - 1);
200 	}
201 	(void)strlcpy(PNbuf, System, sizeof(PNbuf));
202 	for (p = System; *p; p++)
203 		*p = '\0';
204 	PN = PNbuf;
205 	(void)snprintf(sbuf, sizeof sbuf, "tip%d", (int)BR);
206 	System = sbuf;
207 
208 notnumber:
209 	(void)signal(SIGINT, cleanup);
210 	(void)signal(SIGQUIT, cleanup);
211 	(void)signal(SIGHUP, cleanup);
212 	(void)signal(SIGTERM, cleanup);
213 
214 	if ((i = hunt(System)) == 0) {
215 		errx(3, "all ports busy");
216 	}
217 	if (i == -1) {
218 		errx(3, "link down");
219 	}
220 	setbuf(stdout, NULL);
221 
222 	/*
223 	 * Kludge, their's no easy way to get the initialization
224 	 *   in the right order, so force it here
225 	 */
226 	if ((PH = getenv("PHONES")) == NULL)
227 		PH = path_phones;
228 	vinit();				/* init variables */
229 	setparity("none");			/* set the parity table */
230 
231 	/*
232 	 * Hardwired connections require the
233 	 *  line speed set before they make any transmissions
234 	 *  (this is particularly true of things like a DF03-AC)
235 	 */
236 	if (HW) {
237 		if (ttysetup((speed_t)number(value(BAUDRATE))) != 0) {
238 			errx(3, "bad baud rate %d",
239 			    (int)number(value(BAUDRATE)));
240 		}
241 	}
242 	if ((q = tip_connect()) != NULL) {
243 		errx(1, "\07%s\n[EOT]", q);
244 	}
245 	if (!HW) {
246 		if (ttysetup((speed_t)number(value(BAUDRATE))) != 0) {
247 			errx(3, "bad baud rate %d",
248 			    (int)number(value(BAUDRATE)));
249 		}
250 	}
251 
252 
253 cucommon:
254 	/*
255 	 * From here down the code is shared with
256 	 * the "cu" version of tip.
257 	 */
258 
259 	/*
260 	 * Direct connections with no carrier require using O_NONBLOCK on
261 	 * open, but we don't want to keep O_NONBLOCK after open because it
262 	 * will cause busy waits.
263 	 */
264 	if (DC &&
265 	    ((fcarg = fcntl(FD, F_GETFL, 0)) < 0 ||
266 	     fcntl(FD, F_SETFL, fcarg & ~O_NONBLOCK) < 0)) {
267 		err(1, "can't clear O_NONBLOCK");
268 	}
269 
270 	(void)tcgetattr(0, &defterm);
271 	term = defterm;
272 	term.c_lflag &= ~(ICANON|IEXTEN|ECHO);
273 	term.c_iflag &= ~(INPCK|ICRNL);
274 	term.c_oflag &= ~OPOST;
275 	term.c_cc[VMIN] = 1;
276 	term.c_cc[VTIME] = 0;
277 	defchars = term;
278 	term.c_cc[VINTR] = term.c_cc[VQUIT] = term.c_cc[VSUSP] =
279 		term.c_cc[VDSUSP] = term.c_cc[VDISCARD] =
280 	 	term.c_cc[VLNEXT] = _POSIX_VDISABLE;
281 	raw();
282 
283 	(void)pipe(attndes);
284 	(void)pipe(fildes);
285 	(void)pipe(repdes);
286 	(void)signal(SIGALRM, alrmtimeout);
287 
288 	/*
289 	 * Everything's set up now:
290 	 *	connection established (hardwired or dialup)
291 	 *	line conditioned (baud rate, mode, etc.)
292 	 *	internal data structures (variables)
293 	 * so, fork one process for local side and one for remote.
294 	 */
295 	(void)printf("%s", cumode ? "Connected\r\n" : "\07connected\r\n");
296 	switch (pid = fork()) {
297 	default:
298 		tipin();
299 		break;
300 	case 0:
301 		tipout();
302 		break;
303 	case -1:
304 		err(1, "can't fork");
305 	}
306 	/*NOTREACHED*/
307 	exit(0);	/* XXX: pacify gcc */
308 }
309 
310 void
tipusage(void)311 tipusage(void)
312 {
313 	(void)fprintf(stderr, "usage: %s [-v] [-speed] system-name\n",
314 	    getprogname());
315 	(void)fprintf(stderr, "       %s [-v] [-speed] phone-number\n",
316 	    getprogname());
317 	exit(1);
318 }
319 
320 void
321 /*ARGSUSED*/
cleanup(int dummy __unused)322 cleanup(int dummy __unused)
323 {
324 
325 	if (odisc)
326 		(void)ioctl(0, TIOCSETD, &odisc);
327 	_exit(0);
328 }
329 
330 /*
331  * put the controlling keyboard into raw mode
332  */
333 void
raw(void)334 raw(void)
335 {
336 
337 	(void)tcsetattr(0, TCSADRAIN, &term);
338 }
339 
340 
341 /*
342  * return keyboard to normal mode
343  */
344 void
unraw(void)345 unraw(void)
346 {
347 
348 	(void)tcsetattr(0, TCSADRAIN, &defterm);
349 }
350 
351 static	jmp_buf promptbuf;
352 
353 /*
354  * Print string ``s'', then read a string
355  *  in from the terminal.  Handles signals & allows use of
356  *  normal erase and kill characters.
357  */
358 int
prompt(const char * s,char * volatile p,size_t l)359 prompt(const char *s, char *volatile p, size_t l)
360 {
361 	int c;
362 	char *b = p;
363 	sig_t oint, oquit;
364 
365 	stoprompt = 0;
366 	oint = signal(SIGINT, intprompt);
367 	oquit = signal(SIGQUIT, SIG_IGN);
368 	unraw();
369 	(void)printf("%s", s);
370 	if (setjmp(promptbuf) == 0)
371 		while ((c = getchar()) != EOF && (*p = c) != '\n' &&
372 		    b + l > p)
373 			p++;
374 	*p = '\0';
375 
376 	raw();
377 	(void)signal(SIGINT, oint);
378 	(void)signal(SIGQUIT, oquit);
379 	return (stoprompt || p == b);
380 }
381 
382 /*
383  * Interrupt service routine during prompting
384  */
385 static void
386 /*ARGSUSED*/
intprompt(int dummy __unused)387 intprompt(int dummy __unused)
388 {
389 
390 	(void)signal(SIGINT, SIG_IGN);
391 	stoprompt = 1;
392 	(void)printf("\r\n");
393 	longjmp(promptbuf, 1);
394 }
395 
396 /*
397  * getchar() wrapper that checks for EOF on the local end.
398  */
399 static int
xgetchar(void)400 xgetchar(void)
401 {
402 	int c = getchar();
403 	if (__predict_false(c == EOF)) {
404 		cleanup(SIGHUP);
405 		/* NOTREACHED */
406 	}
407 
408 	return c & STRIP_PAR;
409 }
410 
411 
412 /*
413  * ****TIPIN   TIPIN****
414  */
415 static void
tipin(void)416 tipin(void)
417 {
418 	char gch, bol = 1;
419 
420 	/*
421 	 * Kinda klugey here...
422 	 *   check for scripting being turned on from the .tiprc file,
423 	 *   but be careful about just using setscript(), as we may
424 	 *   send a SIGEMT before tipout has a chance to set up catching
425 	 *   it; so wait a second, then setscript()
426 	 */
427 	if (boolean(value(SCRIPT))) {
428 		(void)sleep(1);
429 		setscript();
430 	}
431 
432 	for (;;) {
433 		gch = xgetchar();
434 		if ((gch == character(value(ESCAPE))) && bol) {
435 			if (!(gch = escape()))
436 				continue;
437 		} else if (!cumode &&
438 		    gch && gch == character(value(RAISECHAR))) {
439 			setboolean(value(RAISE), !boolean(value(RAISE)));
440 			continue;
441 		} else if (gch == '\r' || gch == '\n') {
442 			bol = 1;
443 			xpwrite(FD, &gch, 1);
444 			if (boolean(value(HALFDUPLEX)))
445 				(void)printf("%s\n", gch == '\r' ? "\r" : "");
446 			continue;
447 		} else if (!cumode && gch && gch == character(value(FORCE)))
448 			gch = xgetchar();
449 		bol = any(gch, value(EOL));
450 		if (boolean(value(RAISE)) && islower((unsigned char)gch))
451 			gch = toupper((unsigned char)gch);
452 		xpwrite(FD, &gch, 1);
453 		if (boolean(value(HALFDUPLEX)))
454 			(void)printf("%c", gch);
455 	}
456 }
457 
458 /*
459  * Escape handler --
460  *  called on recognition of ``escapec'' at the beginning of a line
461  */
462 int
escape(void)463 escape(void)
464 {
465 	char gch;
466 	esctable_t *p;
467 	char c = character(value(ESCAPE));
468 
469 	gch = xgetchar();
470 	for (p = etable; p->e_char; p++)
471 		if (p->e_char == gch) {
472 			if ((p->e_flags&PRIV) && uid)
473 				continue;
474 			(void)printf("%s", ctrl(c));
475 			(*p->e_func)(gch);
476 			return (0);
477 		}
478 	/* ESCAPE ESCAPE forces ESCAPE */
479 	if (c != gch)
480 		xpwrite(FD, &c, 1);
481 	return (gch);
482 }
483 
484 int
any(char c,const char * p)485 any(char c, const char *p)
486 {
487 
488 	while (p && *p)
489 		if (*p++ == c)
490 			return (1);
491 	return (0);
492 }
493 
494 char *
interp(const char * s)495 interp(const char *s)
496 {
497 	static char buf[256];
498 	char *p = buf, c;
499 	const char *q;
500 
501 	while ((c = *s++) != 0 && buf + sizeof buf - p > 2) {
502 		for (q = "\nn\rr\tt\ff\033E\bb"; *q; q++)
503 			if (*q++ == c) {
504 				*p++ = '\\'; *p++ = *q;
505 				goto next;
506 			}
507 		if (c < 040) {
508 			*p++ = '^'; *p++ = c + 'A'-1;
509 		} else if (c == 0177) {
510 			*p++ = '^'; *p++ = '?';
511 		} else
512 			*p++ = c;
513 	next:
514 		;
515 	}
516 	*p = '\0';
517 	return (buf);
518 }
519 
520 char *
ctrl(char c)521 ctrl(char c)
522 {
523 	static char s[3];
524 
525 	if (c < 040 || c == 0177) {
526 		s[0] = '^';
527 		s[1] = c == 0177 ? '?' : c+'A'-1;
528 		s[2] = '\0';
529 	} else {
530 		s[0] = c;
531 		s[1] = '\0';
532 	}
533 	return (s);
534 }
535 
536 /*
537  * Help command
538  */
539 void
help(char c)540 help(char c)
541 {
542 	esctable_t *p;
543 
544 	(void)printf("%c\r\n", c);
545 	for (p = etable; p->e_char; p++) {
546 		if ((p->e_flags&PRIV) && uid)
547 			continue;
548 		(void)printf("%2s", ctrl(character(value(ESCAPE))));
549 		(void)printf("%-2s %c   %s\r\n", ctrl(p->e_char),
550 			p->e_flags&EXP ? '*': ' ', p->e_help);
551 	}
552 }
553 
554 /*
555  * Set up the "remote" tty's state
556  */
557 int
ttysetup(speed_t spd)558 ttysetup(speed_t spd)
559 {
560 	struct termios	cntrl;
561 
562 	(void)tcgetattr(FD, &cntrl);
563 	(void)cfsetospeed(&cntrl, spd);
564 	(void)cfsetispeed(&cntrl, spd);
565 	cntrl.c_cflag &= ~(CSIZE|PARENB);
566 	cntrl.c_cflag |= CS8;
567 	if (DC)
568 		cntrl.c_cflag |= CLOCAL;
569 	if (boolean(value(HARDWAREFLOW)))
570 		cntrl.c_cflag |= CRTSCTS;
571 	cntrl.c_iflag &= ~(ISTRIP|ICRNL);
572 	cntrl.c_oflag &= ~OPOST;
573 	cntrl.c_lflag &= ~(ICANON|ISIG|IEXTEN|ECHO);
574 	cntrl.c_cc[VMIN] = 1;
575 	cntrl.c_cc[VTIME] = 0;
576 	if (boolean(value(TAND)))
577 		cntrl.c_iflag |= IXOFF|IXON;
578 	else
579 		cntrl.c_iflag &= ~(IXOFF|IXON);
580 	return tcsetattr(FD, TCSAFLUSH, &cntrl);
581 }
582 
583 static char partab[0200];
584 
585 /*
586  * Do a write to the remote machine with the correct parity.
587  * We are doing 8 bit wide output, so we just generate a character
588  * with the right parity and output it.
589  */
590 void
xpwrite(int fd,char * buf,size_t n)591 xpwrite(int fd, char *buf, size_t n)
592 {
593 	size_t i;
594 	char *bp;
595 
596 	bp = buf;
597 	if (bits8 == 0)
598 		for (i = 0; i < n; i++) {
599 			*bp = partab[(*bp) & 0177];
600 			bp++;
601 		}
602 	if (write(fd, buf, n) < 0) {
603 		if (errno == EIO)
604 			tipabort("Lost carrier.");
605 		/* this is questionable */
606 		warn("write");
607 	}
608 }
609 
610 /*
611  * Build a parity table with appropriate high-order bit.
612  */
613 void
setparity(const char * defparity)614 setparity(const char *defparity)
615 {
616 	int i, flip, clr, set;
617 	const char *parity;
618 	static char *curpar;
619 
620 	if (value(PARITY) == NULL || ((char *)value(PARITY))[0] == '\0') {
621 		if (curpar != NULL)
622 			free(curpar);
623 		value(PARITY) = curpar = strdup(defparity);
624 	}
625 	parity = value(PARITY);
626 	if (strcmp(parity, "none") == 0) {
627 		bits8 = 1;
628 		return;
629 	}
630 	bits8 = 0;
631 	flip = 0;
632 	clr = 0377;
633 	set = 0;
634 	if (strcmp(parity, "odd") == 0)
635 		flip = 0200;			/* reverse bit 7 */
636 	else if (strcmp(parity, "zero") == 0)
637 		clr = 0177;			/* turn off bit 7 */
638 	else if (strcmp(parity, "one") == 0)
639 		set = 0200;			/* turn on bit 7 */
640 	else if (strcmp(parity, "even") != 0) {
641 		(void)fprintf(stderr, "%s: unknown parity value\r\n", parity);
642 		(void)fflush(stderr);
643 	}
644 	for (i = 0; i < 0200; i++)
645 		partab[i] = ((evenpartab[i] ^ flip) | set) & clr;
646 }
647