xref: /illumos-gate/usr/src/cmd/tip/tip.c (revision f67950b21e185934ccabe311516f4dcbdb00ef79)
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 /*
23  * Baud rate mapping table
24  */
25 int bauds[] = {
26 	0, 50, 75, 110, 134, 150, 200, 300, 600,
27 	1200, 1800, 2400, 4800, 9600, 19200, 38400,
28 	57600, 76800, 115200, 153600, 230400, 307200,
29 	460800, 921600, -1
30 };
31 
32 extern void	tipout(void)	__NORETURN;
33 extern void	timeout(void);
34 extern esctable_t	etable[];
35 extern unsigned char	evenpartab[];
36 
37 void	intprompt(void);
38 void	deadkid(void);
39 void	cleanup(void);
40 void	tipin(void)	__NORETURN;
41 unsigned char	escape(void);
42 char	*sname(char *);
43 char	PNbuf[256];		/* This limits the size of a number */
44 int	noparity = 0;
45 
46 int
47 main(int argc, char *argv[])
48 {
49 	char *system = NOSTR;
50 	int i;
51 	char *p;
52 	char sbuf[15];
53 
54 	gid = getgid();
55 	egid = getegid();
56 	uid = getuid();
57 	euid = geteuid();
58 	if (equal(sname(argv[0]), "cu")) {
59 		cumode = 1;
60 		cumain(argc, argv);
61 		goto cucommon;
62 	}
63 
64 	if (argc > 4) {
65 		(void) fprintf(stderr,
66 		    "usage: tip [-v] [-speed] [system-name]\n");
67 		return (1);
68 	}
69 	if (!isatty(0)) {
70 		(void) fprintf(stderr, "tip: must be interactive\n");
71 		return (1);
72 	}
73 
74 	for (; argc > 1; argv++, argc--) {
75 		if (argv[1][0] != '-')
76 			system = argv[1];
77 		else switch (argv[1][1]) {
78 
79 		case 'v':
80 			vflag++;
81 			break;
82 
83 		case '0': case '1': case '2': case '3': case '4':
84 		case '5': case '6': case '7': case '8': case '9':
85 			BR = atoi(&argv[1][1]);
86 			break;
87 
88 		default:
89 			(void) fprintf(stderr, "tip: %s, unknown option\n",
90 			    argv[1]);
91 			break;
92 		}
93 	}
94 
95 	(void) setlocale(LC_CTYPE, "");
96 
97 	if (system == NOSTR)
98 		goto notnumber;
99 	for (p = system; *p; p++)
100 		if (isalpha(*p))
101 			goto notnumber;
102 	/*
103 	 * System name is really a phone number...
104 	 * Copy the number then stomp on the original (in case the number
105 	 *	is private, we don't want 'ps' or 'w' to find it).
106 	 */
107 	if (strlen(system) > sizeof (PNbuf) - 1) {
108 		(void) fprintf(stderr,
109 		    "tip: phone number too long (max = %d bytes)\n",
110 		    sizeof (PNbuf) - 1);
111 		return (1);
112 	}
113 	(void) strncpy(PNbuf, system, sizeof (PNbuf) - 1);
114 	for (p = system; *p; p++)
115 		*p = '\0';
116 	PN = PNbuf;
117 	(void) snprintf(sbuf, sizeof (sbuf), "tip%d", BR);
118 	system = sbuf;
119 
120 notnumber:
121 	(void) signal(SIGINT, (sig_handler_t)cleanup);
122 	(void) signal(SIGQUIT, (sig_handler_t)cleanup);
123 	(void) signal(SIGHUP, (sig_handler_t)cleanup);
124 	(void) signal(SIGTERM, (sig_handler_t)cleanup);
125 
126 	if ((i = hunt(system)) == 0) {
127 		(void) printf("all ports busy\n");
128 		return (3);
129 	}
130 	if (i == -1) {
131 		(void) printf("link down\n");
132 		delock(uucplock);
133 		return (3);
134 	}
135 	setbuf(stdout, NULL);
136 	loginit();
137 
138 	/*
139 	 * Now that we have the logfile and the ACU open
140 	 *  return to the real uid and gid.  These things will
141 	 *  be closed on exit.  The saved-setuid uid and gid
142 	 *  allows us to get the original setuid permissions back
143 	 *  for removing the uucp lock.
144 	 */
145 	userperm();
146 
147 	/*
148 	 * Kludge, there's no easy way to get the initialization
149 	 *   in the right order, so force it here.
150 	 * Do the open here, before we change back to real uid.
151 	 * We will check whether the open succeeded later, when
152 	 * (and if) we actually go to use the file.
153 	 */
154 	if ((PH = getenv("PHONES")) == NOSTR) {
155 		myperm();
156 		PH = "/etc/phones";
157 	}
158 	phfd = fopen(PH, "r");
159 
160 	userperm();
161 
162 	vinit();				/* init variables */
163 	setparity("none");			/* set the parity table */
164 	if ((i = speed(number(value(BAUDRATE)))) == 0) {
165 		(void) printf("tip: bad baud rate %d\n",
166 		    number(value(BAUDRATE)));
167 		myperm();
168 		delock(uucplock);
169 		return (3);
170 	}
171 
172 
173 	/*
174 	 * Hardwired connections require the
175 	 *  line speed set before they make any transmissions
176 	 *  (this is particularly true of things like a DF03-AC)
177 	 */
178 	if (HW)
179 		ttysetup(i);
180 	if (p = connect()) {
181 		(void) printf("\07%s\n[EOT]\n", p);
182 		myperm();
183 		delock(uucplock);
184 		return (1);
185 	}
186 
187 	/*
188 	 * Always setup the tty again here in case hardware flow
189 	 *  control was selected, which can only be set after the
190 	 *  connection is made, or in case this is not a hardwired
191 	 *  modem (rare these days) that likewise can only be setup
192 	 *  after the connection is made.
193 	 */
194 	ttysetup(i);
195 cucommon:
196 	/*
197 	 * From here down the code is shared with
198 	 * the "cu" version of tip.
199 	 */
200 
201 	(void) ioctl(0, TCGETS, (char *)&defarg);
202 	arg = defarg;
203 	/* turn off input processing */
204 	arg.c_lflag &= ~(ICANON|ISIG|ECHO|IEXTEN);
205 	arg.c_cc[VMIN] = 1;
206 	arg.c_cc[VTIME] = 0;
207 	arg.c_iflag &= ~(INPCK|IXON|IXOFF|ICRNL);
208 	arg.c_oflag = 0;		/* turn off all output processing */
209 	/* handle tandem mode in case was set in remote file */
210 	if (boolean(value(TAND)))
211 		tandem("on");
212 	else
213 		tandem("off");
214 	raw();
215 
216 	(void) pipe(fildes); (void) pipe(repdes);
217 	(void) signal(SIGALRM, (sig_handler_t)timeout);
218 
219 	/*
220 	 * Everything's set up now:
221 	 *	connection established (hardwired or dialup)
222 	 *	line conditioned (baud rate, mode, etc.)
223 	 *	internal data structures (variables)
224 	 * so, fork one process for local side and one for remote.
225 	 */
226 	if (CM != NOSTR) {
227 		(void) sleep(2);	/* let line settle */
228 		parwrite(FD, (unsigned char *)CM, strlen(CM));
229 	}
230 	(void) printf(cumode ? "Connected\r\n" : "\07connected\r\n");
231 	(void) signal(SIGCHLD, (sig_handler_t)deadkid);
232 	if (pid = fork())
233 		tipin();
234 	else
235 		tipout();
236 	/*NOTREACHED*/
237 }
238 
239 void
240 deadkid(void)
241 {
242 
243 	if (pid >= 0 && waitpid(pid, NULL, WNOHANG) == pid)
244 		tip_abort("Connection Closed");
245 }
246 
247 void
248 cleanup(void)
249 {
250 
251 	if (uid != getuid()) {
252 		myperm();
253 	}
254 	delock(uucplock);
255 	exit(0);
256 }
257 
258 /*
259  * put the controlling keyboard into raw mode
260  */
261 void
262 raw(void)
263 {
264 
265 	(void) ioctl(0, TCSETSF, (char *)&arg);
266 }
267 
268 
269 /*
270  * return keyboard to normal mode
271  */
272 void
273 unraw(void)
274 {
275 
276 	(void) ioctl(0, TCSETSF, (char *)&defarg);
277 }
278 
279 /*
280  * switch to using invoking user's permissions
281  */
282 void
283 userperm(void)
284 {
285 
286 	(void) setegid(gid);
287 	(void) seteuid(uid);
288 }
289 
290 /*
291  * switch to using my special (setuid) permissions
292  */
293 void
294 myperm(void)
295 {
296 
297 	(void) setegid(egid);
298 	(void) seteuid(euid);
299 }
300 
301 static	sigjmp_buf promptbuf;
302 
303 /*
304  * Print string ``s'', then read a string
305  *  in from the terminal.  Handles signals & allows use of
306  *  normal erase and kill characters.
307  */
308 int
309 prompt(char *s, char *p, size_t len)
310 {
311 	char *b = p;
312 	int c;
313 	sig_handler_t	ointr, oquit;
314 
315 	stoprompt = 0;
316 	ointr = signal(SIGINT, (sig_handler_t)intprompt);
317 	oquit = signal(SIGQUIT, SIG_IGN);
318 	unraw();
319 	(void) printf("%s", s);
320 	if (sigsetjmp(promptbuf, 1) == 0)
321 		while (p < b + len - 1 &&
322 		    ((c = getchar()) != EOF) && (c != '\n'))
323 			*p++ = c;
324 	*p = '\0';
325 
326 	raw();
327 	(void) signal(SIGINT, ointr);
328 	(void) signal(SIGQUIT, oquit);
329 	return (stoprompt || p == b);
330 }
331 
332 /*
333  * Interrupt service routine during prompting
334  */
335 void
336 intprompt(void)
337 {
338 
339 	(void) signal(SIGINT, SIG_IGN);
340 	(void) signal(SIGQUIT, SIG_IGN);
341 	stoprompt = 1;
342 	(void) printf("\r\n");
343 	siglongjmp(promptbuf, 1);
344 }
345 
346 /*
347  * ****TIPIN   TIPIN****
348  */
349 void
350 tipin(void)
351 {
352 	unsigned char gch, c;
353 	int bol = 1;
354 
355 	/*
356 	 * Kinda klugey here...
357 	 *   check for scripting being turned on from the .tiprc file,
358 	 *   but be careful about just using setscript(), as we may
359 	 *   send a SIGEMT before tipout has a chance to set up catching
360 	 *   it; so wait a second, then setscript()
361 	 */
362 	if (boolean(value(SCRIPT))) {
363 		(void) sleep(1);
364 		setscript();
365 	}
366 
367 	for (;;) {
368 		gch = getchar()&0377;
369 		if ((gch == character(value(ESCAPE))) && bol) {
370 			if (!(gch = escape()))
371 				continue;
372 		} else if (!cumode && gch == character(value(RAISECHAR))) {
373 			boolean(value(RAISE)) = !boolean(value(RAISE));
374 			continue;
375 		} else if (gch == '\r') {
376 			bol = 1;
377 			parwrite(FD, &gch, 1);
378 			if (boolean(value(HALFDUPLEX)))
379 				(void) printf("\r\n");
380 			continue;
381 		} else if (!cumode && gch == character(value(FORCE)))
382 			gch = getchar()&0377;
383 		bol = any(gch, value(EOL));
384 		if (boolean(value(RAISE)) && islower(gch))
385 			gch = toupper(gch);
386 		c = gch;
387 		parwrite(FD, &gch, 1);
388 		if (boolean(value(HALFDUPLEX)))
389 			(void) putchar(c);
390 	}
391 }
392 
393 /*
394  * Escape handler --
395  *  called on recognition of ``escapec'' at the beginning of a line
396  */
397 unsigned char
398 escape(void)
399 {
400 	unsigned char gch;
401 	esctable_t *p;
402 	char c = character(value(ESCAPE));
403 
404 	gch = (getchar()&0377);
405 	for (p = etable; p->e_char; p++)
406 		if (p->e_char == gch) {
407 			if ((p->e_flags&PRIV) && uid)
408 				continue;
409 			(void) printf("%s", ctrl(c));
410 			(*p->e_func)(gch);
411 			return (0);
412 		}
413 	/* ESCAPE ESCAPE forces ESCAPE */
414 	if (c != gch)
415 		parwrite(FD, (unsigned char *)&c, 1);
416 	return (gch);
417 }
418 
419 int
420 speed(int n)
421 {
422 	int *p;
423 
424 	for (p = bauds; *p != -1;  p++)
425 		if (*p == n)
426 			return (p - bauds);
427 	return (0);
428 }
429 
430 int
431 any(char c, char *p)
432 {
433 	while (p && *p)
434 		if (*p++ == c)
435 			return (1);
436 	return (0);
437 }
438 
439 char *
440 interp(char *s)
441 {
442 	static char buf[256];
443 	char *p = buf, c, *q;
444 
445 	while (c = *s++) {
446 		for (q = "\nn\rr\tt\ff\033E\bb"; *q; q++)
447 			if (*q++ == c) {
448 				*p++ = '\\'; *p++ = *q;
449 				goto next;
450 			}
451 		if (c < 040) {
452 			*p++ = '^'; *p++ = c + 'A'-1;
453 		} else if (c == 0177) {
454 			*p++ = '^'; *p++ = '?';
455 		} else
456 			*p++ = c;
457 	next:
458 		;
459 	}
460 	*p = '\0';
461 	return (buf);
462 }
463 
464 char *
465 ctrl(char c)
466 {
467 	static char s[3];
468 
469 	if (c < 040 || c == 0177) {
470 		s[0] = '^';
471 		s[1] = c == 0177 ? '?' : c+'A'-1;
472 		s[2] = '\0';
473 	} else {
474 		s[0] = c;
475 		s[1] = '\0';
476 	}
477 	return (s);
478 }
479 
480 /*
481  * Help command
482  */
483 void
484 help(int c)
485 {
486 	esctable_t *p;
487 
488 	(void) printf("%c\r\n", c);
489 	for (p = etable; p->e_char; p++) {
490 		if ((p->e_flags&PRIV) && uid)
491 			continue;
492 		(void) printf("%2s", ctrl(character(value(ESCAPE))));
493 		(void) printf("%-2s %c   %s\r\n", ctrl(p->e_char),
494 		    p->e_flags&EXP ? '*': ' ', p->e_help);
495 	}
496 }
497 
498 /*
499  * Set up the "remote" tty's state
500  */
501 void
502 ttysetup(int speed)
503 {
504 	struct termios buf;
505 	char *loc;
506 
507 	(void) ioctl(FD, TCGETS, (char *)&buf);
508 	buf.c_cflag &= (CREAD|HUPCL|CLOCAL|CRTSCTS|CRTSXOFF);
509 	buf.c_cflag |= CS8;
510 	(void) cfsetospeed(&buf, speed);
511 	if (boolean(value(HARDWAREFLOW))) {
512 		int i = TIOCM_CAR;
513 
514 		/*
515 		 * Only set hardware flow control if carrier is up,
516 		 * because some devices require both CD and RTS to
517 		 * be up before sending.
518 		 */
519 		(void) ioctl(FD, TIOCMGET, &i);
520 		if (i & TIOCM_CAR)
521 			buf.c_cflag |= (CRTSCTS|CRTSXOFF);
522 	}
523 
524 	/*
525 	 * Careful to only penalize the 8-bit users here on the
526 	 * incoming tty port.  The default 7-bit users will
527 	 * still get the parity bit from the other side's login
528 	 * process (which happens to be the default for sun tip
529 	 * configurations).
530 	 */
531 	loc = setlocale(LC_CTYPE, NULL);
532 	if (noparity && loc != 0 && strcmp(loc, "C") != 0)
533 		buf.c_iflag = 0;
534 	else
535 		buf.c_iflag = ISTRIP;
536 	buf.c_oflag = 0;
537 	buf.c_lflag = 0;
538 	buf.c_cc[VMIN] = 1;
539 	buf.c_cc[VTIME] = 0;
540 	(void) ioctl(FD, TCSETSF, (char *)&buf);
541 }
542 
543 /*
544  * Return "simple" name from a file name,
545  * strip leading directories.
546  */
547 char *
548 sname(char *s)
549 {
550 	char *p = s;
551 
552 	while (*s)
553 		if (*s++ == '/')
554 			p = s;
555 	return (p);
556 }
557 
558 static char partab[0400];
559 
560 /*
561  * Do a write to the remote machine with the correct parity.
562  * We are doing 8 bit wide output, so we just generate a character
563  * with the right parity and output it.
564  */
565 void
566 parwrite(int fd, unsigned char *buf, int n)
567 {
568 	int i;
569 	unsigned char *bp;
570 
571 	bp = buf;
572 	for (i = 0; i < n; i++) {
573 		*bp = partab[(*bp)&0377];
574 		bp++;
575 	}
576 	if (write(fd, buf, n) < 0) {
577 		if (errno == EIO || errno == ENXIO)
578 			tip_abort("Lost carrier.");
579 		/* this is questionable */
580 		perror("write");
581 	}
582 }
583 
584 /*
585  * Build a parity table with appropriate high-order bit.
586  */
587 void
588 setparity(char *defparity)
589 {
590 	int i;
591 	char *parity;
592 
593 	if (value(PARITY) == NOSTR)
594 		value(PARITY) = defparity;
595 	parity = value(PARITY);
596 	for (i = 0; i < 0400; i++)
597 		partab[i] = evenpartab[i];
598 	if (equal(parity, "even")) {
599 		/* EMPTY */
600 	} else if (equal(parity, "odd")) {
601 		for (i = 0; i < 0400; i++)
602 			partab[i] ^= 0200;	/* reverse bit 7 */
603 	} else if (equal(parity, "none")) {
604 		/* Do nothing so we can pass thru 8-bit chars */
605 		noparity = 1;
606 		for (i = 0; i < 0400; i++)
607 			partab[i] = i;
608 	} else if (equal(parity, "zero")) {
609 		for (i = 0; i < 0400; i++)
610 			partab[i] &= ~0200;	/* turn off bit 7 */
611 	} else if (equal(parity, "one")) {
612 		for (i = 0; i < 0400; i++)
613 			partab[i] |= 0200;	/* turn on bit 7 */
614 	} else {
615 		(void) fprintf(stderr, "%s: unknown parity value\n", PA);
616 		(void) fflush(stderr);
617 	}
618 }
619