xref: /illumos-gate/usr/src/cmd/tip/tip.c (revision 671e12f2cf68dbd241dfc08296dc05fecc27127c)
1 /*
2  * Copyright 2009 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 /*
13  * tip - UNIX link to other systems
14  *  tip [-v] [-speed] system-name
15  * or
16  *  cu phone-number [-s speed] [-l line] [-a acu]
17  */
18 #include "tip.h"
19 #include <sys/wait.h>
20 #include <locale.h>
21 
22 int	vflag;
23 int	cumode;
24 FILE	*phfd;
25 
26 /*
27  * Baud rate mapping table
28  */
29 int bauds[] = {
30 	0, 50, 75, 110, 134, 150, 200, 300, 600,
31 	1200, 1800, 2400, 4800, 9600, 19200, 38400,
32 	57600, 76800, 115200, 153600, 230400, 307200,
33 	460800, 921600, 1000000, 1152000, 1500000,
34 	2000000, 2500000, 3000000, 3500000, 4000000, -1
35 };
36 
37 extern void	tipout(void)	__NORETURN;
38 extern void	timeout(void);
39 extern esctable_t	etable[];
40 extern unsigned char	evenpartab[];
41 
42 void	intprompt(void);
43 void	deadkid(void);
44 void	cleanup(void);
45 void	tipin(void)	__NORETURN;
46 unsigned char	escape(void);
47 char	*sname(char *);
48 char	PNbuf[256];		/* This limits the size of a number */
49 int	noparity = 0;
50 
51 int
52 main(int argc, char *argv[])
53 {
54 	char *system = NOSTR;
55 	int i;
56 	char *p;
57 	char sbuf[15];
58 
59 	gid = getgid();
60 	egid = getegid();
61 	uid = getuid();
62 	euid = geteuid();
63 	if (equal(sname(argv[0]), "cu")) {
64 		cumode = 1;
65 		cumain(argc, argv);
66 		goto cucommon;
67 	}
68 
69 	if (argc > 4) {
70 		(void) fprintf(stderr,
71 		    "usage: tip [-v] [-speed] [system-name]\n");
72 		return (1);
73 	}
74 	if (!isatty(0)) {
75 		(void) fprintf(stderr, "tip: must be interactive\n");
76 		return (1);
77 	}
78 
79 	for (; argc > 1; argv++, argc--) {
80 		if (argv[1][0] != '-')
81 			system = argv[1];
82 		else switch (argv[1][1]) {
83 
84 		case 'v':
85 			vflag++;
86 			break;
87 
88 		case '0': case '1': case '2': case '3': case '4':
89 		case '5': case '6': case '7': case '8': case '9':
90 			BR = atoi(&argv[1][1]);
91 			break;
92 
93 		default:
94 			(void) fprintf(stderr, "tip: %s, unknown option\n",
95 			    argv[1]);
96 			break;
97 		}
98 	}
99 
100 	(void) setlocale(LC_CTYPE, "");
101 
102 	if (system == NOSTR)
103 		goto notnumber;
104 	for (p = system; *p; p++)
105 		if (isalpha(*p))
106 			goto notnumber;
107 	/*
108 	 * System name is really a phone number...
109 	 * Copy the number then stomp on the original (in case the number
110 	 *	is private, we don't want 'ps' or 'w' to find it).
111 	 */
112 	if (strlen(system) > sizeof (PNbuf) - 1) {
113 		(void) fprintf(stderr,
114 		    "tip: phone number too long (max = %d bytes)\n",
115 		    sizeof (PNbuf) - 1);
116 		return (1);
117 	}
118 	(void) strncpy(PNbuf, system, sizeof (PNbuf) - 1);
119 	for (p = system; *p; p++)
120 		*p = '\0';
121 	PN = PNbuf;
122 	(void) snprintf(sbuf, sizeof (sbuf), "tip%d", BR);
123 	system = sbuf;
124 
125 notnumber:
126 	(void) signal(SIGINT, (sig_handler_t)cleanup);
127 	(void) signal(SIGQUIT, (sig_handler_t)cleanup);
128 	(void) signal(SIGHUP, (sig_handler_t)cleanup);
129 	(void) signal(SIGTERM, (sig_handler_t)cleanup);
130 
131 	if ((i = hunt(system)) == 0) {
132 		(void) printf("all ports busy\n");
133 		return (3);
134 	}
135 	if (i == -1) {
136 		(void) printf("link down\n");
137 		delock(uucplock);
138 		return (3);
139 	}
140 	setbuf(stdout, NULL);
141 	loginit();
142 
143 	/*
144 	 * Now that we have the logfile and the ACU open
145 	 *  return to the real uid and gid.  These things will
146 	 *  be closed on exit.  The saved-setuid uid and gid
147 	 *  allows us to get the original setuid permissions back
148 	 *  for removing the uucp lock.
149 	 */
150 	userperm();
151 
152 	/*
153 	 * Kludge, there's no easy way to get the initialization
154 	 *   in the right order, so force it here.
155 	 * Do the open here, before we change back to real uid.
156 	 * We will check whether the open succeeded later, when
157 	 * (and if) we actually go to use the file.
158 	 */
159 	if ((PH = getenv("PHONES")) == NOSTR) {
160 		myperm();
161 		PH = "/etc/phones";
162 	}
163 	phfd = fopen(PH, "r");
164 
165 	userperm();
166 
167 	vinit();				/* init variables */
168 	setparity("none");			/* set the parity table */
169 	if ((i = speed(number(value(BAUDRATE)))) == 0) {
170 		(void) printf("tip: bad baud rate %d\n",
171 		    number(value(BAUDRATE)));
172 		myperm();
173 		delock(uucplock);
174 		return (3);
175 	}
176 
177 
178 	/*
179 	 * Hardwired connections require the
180 	 *  line speed set before they make any transmissions
181 	 *  (this is particularly true of things like a DF03-AC)
182 	 */
183 	if (HW)
184 		ttysetup(i);
185 	if (p = connect()) {
186 		(void) printf("\07%s\n[EOT]\n", p);
187 		myperm();
188 		delock(uucplock);
189 		return (1);
190 	}
191 
192 	/*
193 	 * Always setup the tty again here in case hardware flow
194 	 *  control was selected, which can only be set after the
195 	 *  connection is made, or in case this is not a hardwired
196 	 *  modem (rare these days) that likewise can only be setup
197 	 *  after the connection is made.
198 	 */
199 	ttysetup(i);
200 cucommon:
201 	/*
202 	 * From here down the code is shared with
203 	 * the "cu" version of tip.
204 	 */
205 
206 	(void) ioctl(0, TCGETS, (char *)&defarg);
207 	arg = defarg;
208 	/* turn off input processing */
209 	arg.c_lflag &= ~(ICANON|ISIG|ECHO|IEXTEN);
210 	arg.c_cc[VMIN] = 1;
211 	arg.c_cc[VTIME] = 0;
212 	arg.c_iflag &= ~(INPCK|IXON|IXOFF|ICRNL);
213 	arg.c_oflag = 0;		/* turn off all output processing */
214 	/* handle tandem mode in case was set in remote file */
215 	if (boolean(value(TAND)))
216 		tandem("on");
217 	else
218 		tandem("off");
219 	raw();
220 
221 	(void) pipe(fildes); (void) pipe(repdes);
222 	(void) signal(SIGALRM, (sig_handler_t)timeout);
223 
224 	/*
225 	 * Everything's set up now:
226 	 *	connection established (hardwired or dialup)
227 	 *	line conditioned (baud rate, mode, etc.)
228 	 *	internal data structures (variables)
229 	 * so, fork one process for local side and one for remote.
230 	 */
231 	if (CM != NOSTR) {
232 		(void) sleep(2);	/* let line settle */
233 		parwrite(FD, (unsigned char *)CM, strlen(CM));
234 	}
235 	(void) printf(cumode ? "Connected\r\n" : "\07connected\r\n");
236 	(void) signal(SIGCHLD, (sig_handler_t)deadkid);
237 	if (pid = fork())
238 		tipin();
239 	else
240 		tipout();
241 	/*NOTREACHED*/
242 }
243 
244 void
245 deadkid(void)
246 {
247 
248 	if (pid >= 0 && waitpid(pid, NULL, WNOHANG) == pid)
249 		tip_abort("Connection Closed");
250 }
251 
252 void
253 cleanup(void)
254 {
255 
256 	if (uid != getuid()) {
257 		myperm();
258 	}
259 	delock(uucplock);
260 	exit(0);
261 }
262 
263 /*
264  * put the controlling keyboard into raw mode
265  */
266 void
267 raw(void)
268 {
269 
270 	(void) ioctl(0, TCSETSF, (char *)&arg);
271 }
272 
273 
274 /*
275  * return keyboard to normal mode
276  */
277 void
278 unraw(void)
279 {
280 
281 	(void) ioctl(0, TCSETSF, (char *)&defarg);
282 }
283 
284 /*
285  * switch to using invoking user's permissions
286  */
287 void
288 userperm(void)
289 {
290 
291 	(void) setegid(gid);
292 	(void) seteuid(uid);
293 }
294 
295 /*
296  * switch to using my special (setuid) permissions
297  */
298 void
299 myperm(void)
300 {
301 
302 	(void) setegid(egid);
303 	(void) seteuid(euid);
304 }
305 
306 static	sigjmp_buf promptbuf;
307 
308 /*
309  * Print string ``s'', then read a string
310  *  in from the terminal.  Handles signals & allows use of
311  *  normal erase and kill characters.
312  */
313 int
314 prompt(char *s, char *p, size_t len)
315 {
316 	char *b = p;
317 	int c;
318 	sig_handler_t	ointr, oquit;
319 
320 	stoprompt = 0;
321 	ointr = signal(SIGINT, (sig_handler_t)intprompt);
322 	oquit = signal(SIGQUIT, SIG_IGN);
323 	unraw();
324 	(void) printf("%s", s);
325 	if (sigsetjmp(promptbuf, 1) == 0)
326 		while (p < b + len - 1 &&
327 		    ((c = getchar()) != EOF) && (c != '\n'))
328 			*p++ = c;
329 	*p = '\0';
330 
331 	raw();
332 	(void) signal(SIGINT, ointr);
333 	(void) signal(SIGQUIT, oquit);
334 	return (stoprompt || p == b);
335 }
336 
337 /*
338  * Interrupt service routine during prompting
339  */
340 void
341 intprompt(void)
342 {
343 
344 	(void) signal(SIGINT, SIG_IGN);
345 	(void) signal(SIGQUIT, SIG_IGN);
346 	stoprompt = 1;
347 	(void) printf("\r\n");
348 	siglongjmp(promptbuf, 1);
349 }
350 
351 /*
352  * ****TIPIN   TIPIN****
353  */
354 void
355 tipin(void)
356 {
357 	unsigned char gch, c;
358 	int bol = 1;
359 
360 	/*
361 	 * Kinda klugey here...
362 	 *   check for scripting being turned on from the .tiprc file,
363 	 *   but be careful about just using setscript(), as we may
364 	 *   send a SIGEMT before tipout has a chance to set up catching
365 	 *   it; so wait a second, then setscript()
366 	 */
367 	if (boolean(value(SCRIPT))) {
368 		(void) sleep(1);
369 		setscript();
370 	}
371 
372 	for (;;) {
373 		gch = getchar()&0377;
374 		if ((gch == character(value(ESCAPE))) && bol) {
375 			if (!(gch = escape()))
376 				continue;
377 		} else if (!cumode && gch == character(value(RAISECHAR))) {
378 			boolean(value(RAISE)) = !boolean(value(RAISE));
379 			continue;
380 		} else if (gch == '\r') {
381 			bol = 1;
382 			parwrite(FD, &gch, 1);
383 			if (boolean(value(HALFDUPLEX)))
384 				(void) printf("\r\n");
385 			continue;
386 		} else if (!cumode && gch == character(value(FORCE)))
387 			gch = getchar()&0377;
388 		bol = any(gch, value(EOL));
389 		if (boolean(value(RAISE)) && islower(gch))
390 			gch = toupper(gch);
391 		c = gch;
392 		parwrite(FD, &gch, 1);
393 		if (boolean(value(HALFDUPLEX)))
394 			(void) putchar(c);
395 	}
396 }
397 
398 /*
399  * Escape handler --
400  *  called on recognition of ``escapec'' at the beginning of a line
401  */
402 unsigned char
403 escape(void)
404 {
405 	unsigned char gch;
406 	esctable_t *p;
407 	char c = character(value(ESCAPE));
408 
409 	gch = (getchar()&0377);
410 	for (p = etable; p->e_char; p++)
411 		if (p->e_char == gch) {
412 			if ((p->e_flags&PRIV) && uid)
413 				continue;
414 			(void) printf("%s", ctrl(c));
415 			(*p->e_func)(gch);
416 			return (0);
417 		}
418 	/* ESCAPE ESCAPE forces ESCAPE */
419 	if (c != gch)
420 		parwrite(FD, (unsigned char *)&c, 1);
421 	return (gch);
422 }
423 
424 int
425 speed(int n)
426 {
427 	int *p;
428 
429 	for (p = bauds; *p != -1;  p++)
430 		if (*p == n)
431 			return (p - bauds);
432 	return (0);
433 }
434 
435 int
436 any(char c, char *p)
437 {
438 	while (p && *p)
439 		if (*p++ == c)
440 			return (1);
441 	return (0);
442 }
443 
444 char *
445 interp(char *s)
446 {
447 	static char buf[256];
448 	char *p = buf, c, *q;
449 
450 	while (c = *s++) {
451 		for (q = "\nn\rr\tt\ff\033E\bb"; *q; q++)
452 			if (*q++ == c) {
453 				*p++ = '\\'; *p++ = *q;
454 				goto next;
455 			}
456 		if (c < 040) {
457 			*p++ = '^'; *p++ = c + 'A'-1;
458 		} else if (c == 0177) {
459 			*p++ = '^'; *p++ = '?';
460 		} else
461 			*p++ = c;
462 	next:
463 		;
464 	}
465 	*p = '\0';
466 	return (buf);
467 }
468 
469 char *
470 ctrl(char c)
471 {
472 	static char s[3];
473 
474 	if (c < 040 || c == 0177) {
475 		s[0] = '^';
476 		s[1] = c == 0177 ? '?' : c+'A'-1;
477 		s[2] = '\0';
478 	} else {
479 		s[0] = c;
480 		s[1] = '\0';
481 	}
482 	return (s);
483 }
484 
485 /*
486  * Help command
487  */
488 void
489 help(int c)
490 {
491 	esctable_t *p;
492 
493 	(void) printf("%c\r\n", c);
494 	for (p = etable; p->e_char; p++) {
495 		if ((p->e_flags&PRIV) && uid)
496 			continue;
497 		(void) printf("%2s", ctrl(character(value(ESCAPE))));
498 		(void) printf("%-2s %c   %s\r\n", ctrl(p->e_char),
499 		    p->e_flags&EXP ? '*': ' ', p->e_help);
500 	}
501 }
502 
503 /*
504  * Set up the "remote" tty's state
505  */
506 void
507 ttysetup(int speed)
508 {
509 	struct termios buf;
510 	char *loc;
511 
512 	(void) ioctl(FD, TCGETS, (char *)&buf);
513 	buf.c_cflag &= (CREAD|HUPCL|CLOCAL|CRTSCTS|CRTSXOFF);
514 	buf.c_cflag |= CS8;
515 	(void) cfsetospeed(&buf, speed);
516 	if (boolean(value(HARDWAREFLOW))) {
517 		int i = TIOCM_CAR;
518 
519 		/*
520 		 * Only set hardware flow control if carrier is up,
521 		 * because some devices require both CD and RTS to
522 		 * be up before sending.
523 		 */
524 		(void) ioctl(FD, TIOCMGET, &i);
525 		if (i & TIOCM_CAR)
526 			buf.c_cflag |= (CRTSCTS|CRTSXOFF);
527 	}
528 
529 	/*
530 	 * Careful to only penalize the 8-bit users here on the
531 	 * incoming tty port.  The default 7-bit users will
532 	 * still get the parity bit from the other side's login
533 	 * process (which happens to be the default for sun tip
534 	 * configurations).
535 	 */
536 	loc = setlocale(LC_CTYPE, NULL);
537 	if (noparity && loc != 0 && strcmp(loc, "C") != 0)
538 		buf.c_iflag = 0;
539 	else
540 		buf.c_iflag = ISTRIP;
541 	buf.c_oflag = 0;
542 	buf.c_lflag = 0;
543 	buf.c_cc[VMIN] = 1;
544 	buf.c_cc[VTIME] = 0;
545 	(void) ioctl(FD, TCSETSF, (char *)&buf);
546 }
547 
548 /*
549  * Return "simple" name from a file name,
550  * strip leading directories.
551  */
552 char *
553 sname(char *s)
554 {
555 	char *p = s;
556 
557 	while (*s)
558 		if (*s++ == '/')
559 			p = s;
560 	return (p);
561 }
562 
563 static char partab[0400];
564 
565 /*
566  * Do a write to the remote machine with the correct parity.
567  * We are doing 8 bit wide output, so we just generate a character
568  * with the right parity and output it.
569  */
570 void
571 parwrite(int fd, unsigned char *buf, int n)
572 {
573 	int i;
574 	unsigned char *bp;
575 
576 	bp = buf;
577 	for (i = 0; i < n; i++) {
578 		*bp = partab[(*bp)&0377];
579 		bp++;
580 	}
581 	if (write(fd, buf, n) < 0) {
582 		if (errno == EIO || errno == ENXIO)
583 			tip_abort("Lost carrier.");
584 		/* this is questionable */
585 		perror("write");
586 	}
587 }
588 
589 /*
590  * Build a parity table with appropriate high-order bit.
591  */
592 void
593 setparity(char *defparity)
594 {
595 	int i;
596 	char *parity;
597 
598 	if (value(PARITY) == NOSTR)
599 		value(PARITY) = defparity;
600 	parity = value(PARITY);
601 	for (i = 0; i < 0400; i++)
602 		partab[i] = evenpartab[i];
603 	if (equal(parity, "even")) {
604 		/* EMPTY */
605 	} else if (equal(parity, "odd")) {
606 		for (i = 0; i < 0400; i++)
607 			partab[i] ^= 0200;	/* reverse bit 7 */
608 	} else if (equal(parity, "none")) {
609 		/* Do nothing so we can pass thru 8-bit chars */
610 		noparity = 1;
611 		for (i = 0; i < 0400; i++)
612 			partab[i] = i;
613 	} else if (equal(parity, "zero")) {
614 		for (i = 0; i < 0400; i++)
615 			partab[i] &= ~0200;	/* turn off bit 7 */
616 	} else if (equal(parity, "one")) {
617 		for (i = 0; i < 0400; i++)
618 			partab[i] |= 0200;	/* turn on bit 7 */
619 	} else {
620 		(void) fprintf(stderr, "%s: unknown parity value\n", PA);
621 		(void) fflush(stderr);
622 	}
623 }
624