xref: /illumos-gate/usr/src/cmd/tip/tip.c (revision 94e1761e)
1 /*
2  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*
7  * Copyright (c) 1983 Regents of the University of California.
8  * All rights reserved.  The Berkeley software License Agreement
9  * specifies the terms and conditions for redistribution.
10  */
11 
12 #pragma ident	"%Z%%M%	%I%	%E% SMI"
13 
14 /*
15  * tip - UNIX link to other systems
16  *  tip [-v] [-speed] system-name
17  * or
18  *  cu phone-number [-s speed] [-l line] [-a acu]
19  */
20 #include "tip.h"
21 #include <sys/wait.h>
22 #include <locale.h>
23 
24 /*
25  * Baud rate mapping table
26  */
27 int bauds[] = {
28 	0, 50, 75, 110, 134, 150, 200, 300, 600,
29 	1200, 1800, 2400, 4800, 9600, 19200, 38400,
30 	57600, 76800, 115200, 153600, 230400, 307200, 460800, -1
31 };
32 
33 extern void	tipout(void)	__NORETURN;
34 extern void	timeout(void);
35 extern esctable_t	etable[];
36 extern unsigned char	evenpartab[];
37 
38 void	intprompt(void);
39 void	deadkid(void);
40 void	cleanup(void);
41 void	tipin(void)	__NORETURN;
42 unsigned char	escape(void);
43 char	*sname(char *);
44 char	PNbuf[256];		/* This limits the size of a number */
45 int	noparity = 0;
46 
47 int
48 main(int argc, char *argv[])
49 {
50 	char *system = NOSTR;
51 	int i;
52 	char *p;
53 	char sbuf[15];
54 
55 	gid = getgid();
56 	egid = getegid();
57 	uid = getuid();
58 	euid = geteuid();
59 	if (equal(sname(argv[0]), "cu")) {
60 		cumode = 1;
61 		cumain(argc, argv);
62 		goto cucommon;
63 	}
64 
65 	if (argc > 4) {
66 		(void) fprintf(stderr,
67 		    "usage: tip [-v] [-speed] [system-name]\n");
68 		return (1);
69 	}
70 	if (!isatty(0)) {
71 		(void) fprintf(stderr, "tip: must be interactive\n");
72 		return (1);
73 	}
74 
75 	for (; argc > 1; argv++, argc--) {
76 		if (argv[1][0] != '-')
77 			system = argv[1];
78 		else switch (argv[1][1]) {
79 
80 		case 'v':
81 			vflag++;
82 			break;
83 
84 		case '0': case '1': case '2': case '3': case '4':
85 		case '5': case '6': case '7': case '8': case '9':
86 			BR = atoi(&argv[1][1]);
87 			break;
88 
89 		default:
90 			(void) fprintf(stderr, "tip: %s, unknown option\n",
91 			    argv[1]);
92 			break;
93 		}
94 	}
95 
96 	(void) setlocale(LC_CTYPE, "");
97 
98 	if (system == NOSTR)
99 		goto notnumber;
100 	for (p = system; *p; p++)
101 		if (isalpha(*p))
102 			goto notnumber;
103 	/*
104 	 * System name is really a phone number...
105 	 * Copy the number then stomp on the original (in case the number
106 	 *	is private, we don't want 'ps' or 'w' to find it).
107 	 */
108 	if (strlen(system) > sizeof (PNbuf) - 1) {
109 		(void) fprintf(stderr,
110 		    "tip: phone number too long (max = %d bytes)\n",
111 		    sizeof (PNbuf) - 1);
112 		return (1);
113 	}
114 	(void) strncpy(PNbuf, system, sizeof (PNbuf) - 1);
115 	for (p = system; *p; p++)
116 		*p = '\0';
117 	PN = PNbuf;
118 	(void) snprintf(sbuf, sizeof (sbuf), "tip%d", BR);
119 	system = sbuf;
120 
121 notnumber:
122 	(void) signal(SIGINT, (sig_handler_t)cleanup);
123 	(void) signal(SIGQUIT, (sig_handler_t)cleanup);
124 	(void) signal(SIGHUP, (sig_handler_t)cleanup);
125 	(void) signal(SIGTERM, (sig_handler_t)cleanup);
126 
127 	if ((i = hunt(system)) == 0) {
128 		(void) printf("all ports busy\n");
129 		return (3);
130 	}
131 	if (i == -1) {
132 		(void) printf("link down\n");
133 		delock(uucplock);
134 		return (3);
135 	}
136 	setbuf(stdout, NULL);
137 	loginit();
138 
139 	/*
140 	 * Now that we have the logfile and the ACU open
141 	 *  return to the real uid and gid.  These things will
142 	 *  be closed on exit.  The saved-setuid uid and gid
143 	 *  allows us to get the original setuid permissions back
144 	 *  for removing the uucp lock.
145 	 */
146 	userperm();
147 
148 	/*
149 	 * Kludge, there's no easy way to get the initialization
150 	 *   in the right order, so force it here.
151 	 * Do the open here, before we change back to real uid.
152 	 * We will check whether the open succeeded later, when
153 	 * (and if) we actually go to use the file.
154 	 */
155 	if ((PH = getenv("PHONES")) == NOSTR) {
156 		myperm();
157 		PH = "/etc/phones";
158 	}
159 	phfd = fopen(PH, "r");
160 
161 	userperm();
162 
163 	vinit();				/* init variables */
164 	setparity("none");			/* set the parity table */
165 	if ((i = speed(number(value(BAUDRATE)))) == NULL) {
166 		(void) printf("tip: bad baud rate %d\n",
167 		    number(value(BAUDRATE)));
168 		myperm();
169 		delock(uucplock);
170 		return (3);
171 	}
172 
173 
174 	/*
175 	 * Hardwired connections require the
176 	 *  line speed set before they make any transmissions
177 	 *  (this is particularly true of things like a DF03-AC)
178 	 */
179 	if (HW)
180 		ttysetup(i);
181 	if (p = connect()) {
182 		(void) printf("\07%s\n[EOT]\n", p);
183 		myperm();
184 		delock(uucplock);
185 		return (1);
186 	}
187 
188 	/*
189 	 * Always setup the tty again here in case hardware flow
190 	 *  control was selected, which can only be set after the
191 	 *  connection is made, or in case this is not a hardwired
192 	 *  modem (rare these days) that likewise can only be setup
193 	 *  after the connection is made.
194 	 */
195 	ttysetup(i);
196 cucommon:
197 	/*
198 	 * From here down the code is shared with
199 	 * the "cu" version of tip.
200 	 */
201 
202 	(void) ioctl(0, TCGETS, (char *)&defarg);
203 	arg = defarg;
204 	/* turn off input processing */
205 	arg.c_lflag &= ~(ICANON|ISIG|ECHO|IEXTEN);
206 	arg.c_cc[VMIN] = 1;
207 	arg.c_cc[VTIME] = 0;
208 	arg.c_iflag &= ~(INPCK|IXON|IXOFF|ICRNL);
209 	arg.c_oflag = 0;		/* turn off all output processing */
210 	/* handle tandem mode in case was set in remote file */
211 	if (boolean(value(TAND)))
212 		tandem("on");
213 	else
214 		tandem("off");
215 	raw();
216 
217 	(void) pipe(fildes); (void) pipe(repdes);
218 	(void) signal(SIGALRM, (sig_handler_t)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 	if (CM != NOSTR) {
228 		(void) sleep(2);	/* let line settle */
229 		parwrite(FD, (unsigned char *)CM, strlen(CM));
230 	}
231 	(void) printf(cumode ? "Connected\r\n" : "\07connected\r\n");
232 	(void) signal(SIGCHLD, (sig_handler_t)deadkid);
233 	if (pid = fork())
234 		tipin();
235 	else
236 		tipout();
237 	/*NOTREACHED*/
238 }
239 
240 void
241 deadkid(void)
242 {
243 
244 	if (pid >= 0 && waitpid(pid, NULL, WNOHANG) == pid)
245 		tip_abort("Connection Closed");
246 }
247 
248 void
249 cleanup(void)
250 {
251 
252 	if (uid != getuid()) {
253 		myperm();
254 	}
255 	delock(uucplock);
256 	exit(0);
257 }
258 
259 /*
260  * put the controlling keyboard into raw mode
261  */
262 void
263 raw(void)
264 {
265 
266 	(void) ioctl(0, TCSETSF, (char *)&arg);
267 }
268 
269 
270 /*
271  * return keyboard to normal mode
272  */
273 void
274 unraw(void)
275 {
276 
277 	(void) ioctl(0, TCSETSF, (char *)&defarg);
278 }
279 
280 /*
281  * switch to using invoking user's permissions
282  */
283 void
284 userperm(void)
285 {
286 
287 	(void) setegid(gid);
288 	(void) seteuid(uid);
289 }
290 
291 /*
292  * switch to using my special (setuid) permissions
293  */
294 void
295 myperm(void)
296 {
297 
298 	(void) setegid(egid);
299 	(void) seteuid(euid);
300 }
301 
302 static	sigjmp_buf promptbuf;
303 
304 /*
305  * Print string ``s'', then read a string
306  *  in from the terminal.  Handles signals & allows use of
307  *  normal erase and kill characters.
308  */
309 int
310 prompt(char *s, char *p, size_t len)
311 {
312 	char *b = p;
313 	int c;
314 	sig_handler_t	ointr, oquit;
315 
316 	stoprompt = 0;
317 	ointr = signal(SIGINT, (sig_handler_t)intprompt);
318 	oquit = signal(SIGQUIT, SIG_IGN);
319 	unraw();
320 	(void) printf("%s", s);
321 	if (sigsetjmp(promptbuf, 1) == 0)
322 		while (p < b + len - 1 &&
323 		    ((c = getchar()) != EOF) && (c != '\n'))
324 			*p++ = c;
325 	*p = '\0';
326 
327 	raw();
328 	(void) signal(SIGINT, ointr);
329 	(void) signal(SIGQUIT, oquit);
330 	return (stoprompt || p == b);
331 }
332 
333 /*
334  * Interrupt service routine during prompting
335  */
336 void
337 intprompt(void)
338 {
339 
340 	(void) signal(SIGINT, SIG_IGN);
341 	(void) signal(SIGQUIT, SIG_IGN);
342 	stoprompt = 1;
343 	(void) printf("\r\n");
344 	siglongjmp(promptbuf, 1);
345 }
346 
347 /*
348  * ****TIPIN   TIPIN****
349  */
350 void
351 tipin(void)
352 {
353 	unsigned char gch, c;
354 	int bol = 1;
355 
356 	/*
357 	 * Kinda klugey here...
358 	 *   check for scripting being turned on from the .tiprc file,
359 	 *   but be careful about just using setscript(), as we may
360 	 *   send a SIGEMT before tipout has a chance to set up catching
361 	 *   it; so wait a second, then setscript()
362 	 */
363 	if (boolean(value(SCRIPT))) {
364 		(void) sleep(1);
365 		setscript();
366 	}
367 
368 	for (;;) {
369 		gch = getchar()&0377;
370 		if ((gch == character(value(ESCAPE))) && bol) {
371 			if (!(gch = escape()))
372 				continue;
373 		} else if (!cumode && gch == character(value(RAISECHAR))) {
374 			boolean(value(RAISE)) = !boolean(value(RAISE));
375 			continue;
376 		} else if (gch == '\r') {
377 			bol = 1;
378 			parwrite(FD, &gch, 1);
379 			if (boolean(value(HALFDUPLEX)))
380 				(void) printf("\r\n");
381 			continue;
382 		} else if (!cumode && gch == character(value(FORCE)))
383 			gch = getchar()&0377;
384 		bol = any(gch, value(EOL));
385 		if (boolean(value(RAISE)) && islower(gch))
386 			gch = toupper(gch);
387 		c = gch;
388 		parwrite(FD, &gch, 1);
389 		if (boolean(value(HALFDUPLEX)))
390 			(void) putchar(c);
391 	}
392 }
393 
394 /*
395  * Escape handler --
396  *  called on recognition of ``escapec'' at the beginning of a line
397  */
398 unsigned char
399 escape(void)
400 {
401 	unsigned char gch;
402 	esctable_t *p;
403 	char c = character(value(ESCAPE));
404 
405 	gch = (getchar()&0377);
406 	for (p = etable; p->e_char; p++)
407 		if (p->e_char == gch) {
408 			if ((p->e_flags&PRIV) && uid)
409 				continue;
410 			(void) printf("%s", ctrl(c));
411 			(*p->e_func)(gch);
412 			return (0);
413 		}
414 	/* ESCAPE ESCAPE forces ESCAPE */
415 	if (c != gch)
416 		parwrite(FD, (unsigned char *)&c, 1);
417 	return (gch);
418 }
419 
420 int
421 speed(int n)
422 {
423 	int *p;
424 
425 	for (p = bauds; *p != -1;  p++)
426 		if (*p == n)
427 			return (p - bauds);
428 	return (0);
429 }
430 
431 int
432 any(char c, char *p)
433 {
434 	while (p && *p)
435 		if (*p++ == c)
436 			return (1);
437 	return (0);
438 }
439 
440 char *
441 interp(char *s)
442 {
443 	static char buf[256];
444 	char *p = buf, c, *q;
445 
446 	while (c = *s++) {
447 		for (q = "\nn\rr\tt\ff\033E\bb"; *q; q++)
448 			if (*q++ == c) {
449 				*p++ = '\\'; *p++ = *q;
450 				goto next;
451 			}
452 		if (c < 040) {
453 			*p++ = '^'; *p++ = c + 'A'-1;
454 		} else if (c == 0177) {
455 			*p++ = '^'; *p++ = '?';
456 		} else
457 			*p++ = c;
458 	next:
459 		;
460 	}
461 	*p = '\0';
462 	return (buf);
463 }
464 
465 char *
466 ctrl(char c)
467 {
468 	static char s[3];
469 
470 	if (c < 040 || c == 0177) {
471 		s[0] = '^';
472 		s[1] = c == 0177 ? '?' : c+'A'-1;
473 		s[2] = '\0';
474 	} else {
475 		s[0] = c;
476 		s[1] = '\0';
477 	}
478 	return (s);
479 }
480 
481 /*
482  * Help command
483  */
484 void
485 help(int c)
486 {
487 	esctable_t *p;
488 
489 	(void) printf("%c\r\n", c);
490 	for (p = etable; p->e_char; p++) {
491 		if ((p->e_flags&PRIV) && uid)
492 			continue;
493 		(void) printf("%2s", ctrl(character(value(ESCAPE))));
494 		(void) printf("%-2s %c   %s\r\n", ctrl(p->e_char),
495 		    p->e_flags&EXP ? '*': ' ', p->e_help);
496 	}
497 }
498 
499 /*
500  * Set up the "remote" tty's state
501  */
502 void
503 ttysetup(int speed)
504 {
505 	struct termios buf;
506 	char *loc;
507 
508 	(void) ioctl(FD, TCGETS, (char *)&buf);
509 	buf.c_cflag &= (CREAD|HUPCL|CLOCAL|CRTSCTS|CRTSXOFF);
510 	buf.c_cflag |= CS8;
511 	(void) cfsetospeed(&buf, speed);
512 	if (boolean(value(HARDWAREFLOW))) {
513 		int i = TIOCM_CAR;
514 
515 		/*
516 		 * Only set hardware flow control if carrier is up,
517 		 * because some devices require both CD and RTS to
518 		 * be up before sending.
519 		 */
520 		(void) ioctl(FD, TIOCMGET, &i);
521 		if (i & TIOCM_CAR)
522 			buf.c_cflag |= (CRTSCTS|CRTSXOFF);
523 	}
524 
525 	/*
526 	 * Careful to only penalize the 8-bit users here on the
527 	 * incoming tty port.  The default 7-bit users will
528 	 * still get the parity bit from the other side's login
529 	 * process (which happens to be the default for sun tip
530 	 * configurations).
531 	 */
532 	loc = setlocale(LC_CTYPE, NULL);
533 	if (noparity && loc != 0 && strcmp(loc, "C") != 0)
534 		buf.c_iflag = 0;
535 	else
536 		buf.c_iflag = ISTRIP;
537 	buf.c_oflag = 0;
538 	buf.c_lflag = 0;
539 	buf.c_cc[VMIN] = 1;
540 	buf.c_cc[VTIME] = 0;
541 	(void) ioctl(FD, TCSETSF, (char *)&buf);
542 }
543 
544 /*
545  * Return "simple" name from a file name,
546  * strip leading directories.
547  */
548 char *
549 sname(char *s)
550 {
551 	char *p = s;
552 
553 	while (*s)
554 		if (*s++ == '/')
555 			p = s;
556 	return (p);
557 }
558 
559 static char partab[0400];
560 
561 /*
562  * Do a write to the remote machine with the correct parity.
563  * We are doing 8 bit wide output, so we just generate a character
564  * with the right parity and output it.
565  */
566 void
567 parwrite(int fd, unsigned char *buf, int n)
568 {
569 	int i;
570 	unsigned char *bp;
571 
572 	bp = buf;
573 	for (i = 0; i < n; i++) {
574 		*bp = partab[(*bp)&0377];
575 		bp++;
576 	}
577 	if (write(fd, buf, n) < 0) {
578 		if (errno == EIO || errno == ENXIO)
579 			tip_abort("Lost carrier.");
580 		/* this is questionable */
581 		perror("write");
582 	}
583 }
584 
585 /*
586  * Build a parity table with appropriate high-order bit.
587  */
588 void
589 setparity(char *defparity)
590 {
591 	int i;
592 	char *parity;
593 
594 	if (value(PARITY) == NOSTR)
595 		value(PARITY) = defparity;
596 	parity = value(PARITY);
597 	for (i = 0; i < 0400; i++)
598 		partab[i] = evenpartab[i];
599 	if (equal(parity, "even")) {
600 		/* EMPTY */
601 	} else if (equal(parity, "odd")) {
602 		for (i = 0; i < 0400; i++)
603 			partab[i] ^= 0200;	/* reverse bit 7 */
604 	} else if (equal(parity, "none")) {
605 		/* Do nothing so we can pass thru 8-bit chars */
606 		noparity = 1;
607 		for (i = 0; i < 0400; i++)
608 			partab[i] = i;
609 	} else if (equal(parity, "zero")) {
610 		for (i = 0; i < 0400; i++)
611 			partab[i] &= ~0200;	/* turn off bit 7 */
612 	} else if (equal(parity, "one")) {
613 		for (i = 0; i < 0400; i++)
614 			partab[i] |= 0200;	/* turn on bit 7 */
615 	} else {
616 		(void) fprintf(stderr, "%s: unknown parity value\n", PA);
617 		(void) fflush(stderr);
618 	}
619 }
620