tip.c revision 77120 
1/*
2 * Copyright (c) 1983, 1993
3 *	The Regents of the University of California.  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
35static const char copyright[] =
36"@(#) Copyright (c) 1983, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41#if 0
42static char sccsid[] = "@(#)tip.c	8.1 (Berkeley) 6/6/93";
43#endif
44static const char rcsid[] =
45  "$FreeBSD: head/usr.bin/tip/tip/tip.c 77120 2001-05-24 09:27:02Z phk $";
46#endif /* not lint */
47
48/*
49	Forward declarations
50*/
51void ttysetup (int speed);
52
53/*
54 * tip - UNIX link to other systems
55 *  tip [-v] [-speed] system-name
56 * or
57 *  cu phone-number [-s speed] [-l line] [-a acu]
58 */
59
60#include <err.h>
61#include <errno.h>
62#include <sys/types.h>
63#include <libutil.h>
64#include "tipconf.h"
65#include "tip.h"
66#include "pathnames.h"
67
68/*
69 * Baud rate mapping table
70 */
71#if !HAVE_TERMIOS
72CONST int bauds[] = {
73	0, 50, 75, 110, 134, 150, 200, 300, 600,
74	1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200, -1
75};
76#endif
77
78#if !HAVE_TERMIOS
79int	disc = OTTYDISC;		/* tip normally runs this way */
80#endif
81
82void	intprompt();
83void	timeout();
84void	killchild();
85void	cleanup();
86void	tipdone();
87char	*sname();
88char	PNbuf[256];			/* This limits the size of a number */
89
90static void usage __P((void));
91void setparity __P((char *));
92void xpwrite __P((int, char *, int));
93char escape __P((void));
94void tipin __P((void));
95int prompt __P((char *, char *, size_t));
96void unraw __P((void));
97void shell_uid __P((void));
98void daemon_uid __P((void));
99void user_uid __P((void));
100int speed __P((int));
101
102int
103main(argc, argv)
104	char *argv[];
105{
106	char *system = NOSTR;
107	register int i;
108	register char *p;
109	char sbuf[12];
110
111	gid = getgid();
112	egid = getegid();
113	uid = getuid();
114	euid = geteuid();
115
116#if INCLUDE_CU_INTERFACE
117	if (equal(sname(argv[0]), "cu")) {
118		cumode = 1;
119		cumain(argc, argv);
120		goto cucommon;
121	}
122#endif /* INCLUDE_CU_INTERFACE */
123
124	if (argc > 4)
125		usage();
126	if (!isatty(0))
127		errx(1, "must be interactive");
128
129	for (; argc > 1; argv++, argc--) {
130		if (argv[1][0] != '-')
131			system = argv[1];
132		else switch (argv[1][1]) {
133
134		case 'v':
135			vflag++;
136			break;
137
138		case '0': case '1': case '2': case '3': case '4':
139		case '5': case '6': case '7': case '8': case '9':
140			BR = atoi(&argv[1][1]);
141			break;
142
143		default:
144			warnx("%s, unknown option", argv[1]);
145			break;
146		}
147	}
148
149	if (system == NOSTR)
150		goto notnumber;
151	if (isalpha(*system))
152		goto notnumber;
153	/*
154	 * System name is really a phone number...
155	 * Copy the number then stomp on the original (in case the number
156	 *	is private, we don't want 'ps' or 'w' to find it).
157	 */
158	if (strlen(system) > sizeof(PNbuf) - 1)
159		errx(1, "phone number too long (max = %d bytes)", sizeof PNbuf - 1);
160	strncpy(PNbuf, system, sizeof(PNbuf) - 1);
161	for (p = system; *p; p++)
162		*p = '\0';
163	PN = PNbuf;
164	(void)snprintf(sbuf, sizeof(sbuf), "tip%ld", BR);
165	system = sbuf;
166
167notnumber:
168	(void)signal(SIGINT, cleanup);
169	(void)signal(SIGQUIT, cleanup);
170	(void)signal(SIGHUP, cleanup);
171	(void)signal(SIGTERM, cleanup);
172	(void)signal(SIGUSR1, tipdone);
173
174	if ((i = hunt(system)) == 0) {
175		printf("all ports busy\n");
176		exit(3);
177	}
178	if (i == -1) {
179		printf("link down\n");
180		(void)uu_unlock(uucplock);
181		exit(3);
182	}
183	setbuf(stdout, NULL);
184	loginit();
185
186	/*
187	 * Kludge, their's no easy way to get the initialization
188	 *   in the right order, so force it here
189	 */
190	if ((PH = getenv("PHONES")) == NOSTR)
191		PH = _PATH_PHONES;
192	vinit();				/* init variables */
193	setparity("even");			/* set the parity table */
194	if ((i = speed(number(value(BAUDRATE)))) == 0) {
195		printf("tip: bad baud rate %d\n", number(value(BAUDRATE)));
196		(void)uu_unlock(uucplock);
197		exit(3);
198	}
199
200	/*
201	 * Now that we have the logfile and the ACU open
202	 *  return to the real uid and gid.  These things will
203	 *  be closed on exit.  Swap real and effective uid's
204	 *  so we can get the original permissions back
205	 *  for removing the uucp lock.
206	 */
207	user_uid();
208
209	/*
210	 * Hardwired connections require the
211	 *  line speed set before they make any transmissions
212	 *  (this is particularly true of things like a DF03-AC)
213	 */
214	if (HW)
215		ttysetup(i);
216	if ((p = connect())) {
217		printf("\07%s\n[EOT]\n", p);
218		daemon_uid();
219		(void)uu_unlock(uucplock);
220		exit(1);
221	}
222	if (!HW)
223		ttysetup(i);
224/* cucommon:*/
225	/*
226	 * From here down the code is shared with
227	 * the "cu" version of tip.
228	 */
229
230#if HAVE_TERMIOS
231	tcgetattr (0, &otermios);
232	ctermios = otermios;
233#ifndef _POSIX_SOURCE
234	ctermios.c_iflag = (IMAXBEL|IXANY|ISTRIP|IXON|BRKINT);
235	ctermios.c_lflag = (PENDIN|IEXTEN|ISIG|ECHOCTL|ECHOE|ECHOKE);
236#else
237	ctermios.c_iflag = (ISTRIP|IXON|BRKINT);
238	ctermios.c_lflag = (PENDIN|IEXTEN|ISIG|ECHOE);
239#endif
240	ctermios.c_cflag = (CLOCAL|HUPCL|CREAD|CS8);
241	ctermios.c_cc[VINTR] = 	ctermios.c_cc[VQUIT] = -1;
242	ctermios.c_cc[VSUSP] = ctermios.c_cc[VDSUSP] = ctermios.c_cc[VDISCARD] =
243		ctermios.c_cc[VLNEXT] = -1;
244#else /* HAVE_TERMIOS */
245	ioctl(0, TIOCGETP, (char *)&defarg);
246	ioctl(0, TIOCGETC, (char *)&defchars);
247	ioctl(0, TIOCGLTC, (char *)&deflchars);
248	ioctl(0, TIOCGETD, (char *)&odisc);
249	arg = defarg;
250	arg.sg_flags = ANYP | CBREAK;
251	tchars = defchars;
252	tchars.t_intrc = tchars.t_quitc = -1;
253	ltchars = deflchars;
254	ltchars.t_suspc = ltchars.t_dsuspc = ltchars.t_flushc
255		= ltchars.t_lnextc = -1;
256#endif /* HAVE_TERMIOS */
257	raw();
258
259	pipe(fildes); pipe(repdes);
260	(void)signal(SIGALRM, timeout);
261
262	/*
263	 * Everything's set up now:
264	 *	connection established (hardwired or dialup)
265	 *	line conditioned (baud rate, mode, etc.)
266	 *	internal data structures (variables)
267	 * so, fork one process for local side and one for remote.
268	 */
269	printf(cumode ? "Connected\r\n" : "\07connected\r\n");
270
271	if (LI != NOSTR && tiplink (LI, 0) != 0) {
272		tipabort ("login failed");
273	}
274
275	if ((pid = fork()))
276		tipin();
277	else
278		tipout();
279	/*NOTREACHED*/
280}
281
282static void
283usage()
284{
285	fprintf(stderr, "usage: tip [-v] [-speed] [system-name]\n");
286	exit(1);
287}
288
289void
290killchild()
291{
292	if (pid != 0) {
293		kill(pid, SIGTERM);
294		pid = 0;
295	}
296}
297
298void
299cleanup()
300{
301
302	daemon_uid();
303	(void)uu_unlock(uucplock);
304#if !HAVE_TERMIOS
305	if (odisc)
306		ioctl(0, TIOCSETD, (char *)&odisc);
307#endif
308	exit(0);
309}
310
311void
312tipdone()
313{
314	tipabort("Hangup.");
315}
316/*
317 * Muck with user ID's.  We are setuid to the owner of the lock
318 * directory when we start.  user_uid() reverses real and effective
319 * ID's after startup, to run with the user's permissions.
320 * daemon_uid() switches back to the privileged uid for unlocking.
321 * Finally, to avoid running a shell with the wrong real uid,
322 * shell_uid() sets real and effective uid's to the user's real ID.
323 */
324static int uidswapped;
325
326void
327user_uid()
328{
329	if (uidswapped == 0) {
330		seteuid(uid);
331		uidswapped = 1;
332	}
333}
334
335void
336daemon_uid()
337{
338	if (uidswapped) {
339		seteuid(euid);
340		uidswapped = 0;
341	}
342}
343
344void
345shell_uid()
346{
347	setegid(gid);
348	seteuid(uid);
349}
350
351/*
352 * put the controlling keyboard into raw mode
353 */
354void
355raw ()
356{
357#if HAVE_TERMIOS
358	tcsetattr (0, TCSANOW, &ctermios);
359#else /* HAVE_TERMIOS */
360
361	ioctl(0, TIOCSETP, &arg);
362	ioctl(0, TIOCSETC, &tchars);
363	ioctl(0, TIOCSLTC, &ltchars);
364	ioctl(0, TIOCSETD, (char *)&disc);
365#endif /* HAVE_TERMIOS */
366}
367
368
369/*
370 * return keyboard to normal mode
371 */
372void
373unraw()
374{
375#if HAVE_TERMIOS
376	tcsetattr (0, TCSANOW, &otermios);
377#else /* HAVE_TERMIOS */
378
379	ioctl(0, TIOCSETD, (char *)&odisc);
380	ioctl(0, TIOCSETP, (char *)&defarg);
381	ioctl(0, TIOCSETC, (char *)&defchars);
382	ioctl(0, TIOCSLTC, (char *)&deflchars);
383#endif /* HAVE_TERMIOS */
384}
385
386static	jmp_buf promptbuf;
387
388/*
389 * Print string ``s'', then read a string
390 *  in from the terminal.  Handles signals & allows use of
391 *  normal erase and kill characters.
392 */
393int
394prompt(s, p, sz)
395	char *s;
396	register char *p;
397	size_t sz;
398{
399	register char *b = p;
400	sig_t oint, oquit;
401
402	stoprompt = 0;
403	oint = signal(SIGINT, intprompt);
404	oquit = signal(SIGQUIT, SIG_IGN);
405	unraw();
406	printf("%s", s);
407	if (setjmp(promptbuf) == 0)
408		while ((*p = getchar()) != EOF && *p != '\n' && --sz > 0)
409			p++;
410	*p = '\0';
411
412	raw();
413	(void)signal(SIGINT, oint);
414	(void)signal(SIGQUIT, oquit);
415	return (stoprompt || p == b);
416}
417
418/*
419 * Interrupt service routine during prompting
420 */
421void
422intprompt()
423{
424
425	(void)signal(SIGINT, SIG_IGN);
426	stoprompt = 1;
427	printf("\r\n");
428	longjmp(promptbuf, 1);
429}
430
431/*
432 * ****TIPIN   TIPIN****
433 */
434void
435tipin()
436{
437	int i;
438	char gch, bol = 1;
439
440	atexit(killchild);
441
442	/*
443	 * Kinda klugey here...
444	 *   check for scripting being turned on from the .tiprc file,
445	 *   but be careful about just using setscript(), as we may
446	 *   send a SIGEMT before tipout has a chance to set up catching
447	 *   it; so wait a second, then setscript()
448	 */
449	if (boolean(value(SCRIPT))) {
450		sleep(1);
451		setscript();
452	}
453
454	while (1) {
455		i = getchar();
456		if (i == EOF)
457			break;
458		gch = i&0177;
459		if ((gch == character(value(ESCAPE))) && bol) {
460			if (!(gch = escape()))
461				continue;
462		} else if (!cumode && gch == character(value(RAISECHAR))) {
463			boolean(value(RAISE)) = !boolean(value(RAISE));
464			continue;
465		} else if (gch == '\r') {
466			bol = 1;
467			xpwrite(FD, &gch, 1);
468			if (boolean(value(HALFDUPLEX)))
469				printf("\r\n");
470			continue;
471		} else if (!cumode && gch == character(value(FORCE))) {
472			i = getchar();
473			if (i == EOF)
474				break;
475			gch = i & 0177;
476		}
477		bol = any(gch, value(EOL));
478		if (boolean(value(RAISE)) && islower(gch))
479			gch = toupper(gch);
480		xpwrite(FD, &gch, 1);
481		if (boolean(value(HALFDUPLEX)))
482			printf("%c", gch);
483	}
484}
485
486extern esctable_t etable[];
487
488/*
489 * Escape handler --
490 *  called on recognition of ``escapec'' at the beginning of a line
491 */
492char
493escape()
494{
495	register char gch;
496	register esctable_t *p;
497	char c = character(value(ESCAPE));
498	int i;
499
500	i = getchar();
501	if (i == EOF)
502		return 0;
503	gch = (i&0177);
504	for (p = etable; p->e_char; p++)
505		if (p->e_char == gch) {
506			if ((p->e_flags&PRIV) && uid)
507				continue;
508			printf("%s", ctrl(c));
509			(*p->e_func)(gch);
510			return (0);
511		}
512	/* ESCAPE ESCAPE forces ESCAPE */
513	if (c != gch)
514		xpwrite(FD, &c, 1);
515	return (gch);
516}
517
518int
519speed(n)
520	int n;
521{
522#if HAVE_TERMIOS
523	return (n);
524#else
525	register CONST int *p;
526
527	for (p = bauds; *p != -1;  p++)
528		if (*p == n)
529			return (p - bauds);
530	return (NULL);
531#endif
532}
533
534int
535any(c, p)
536	register char c, *p;
537{
538	while (p && *p)
539		if (*p++ == c)
540			return (1);
541	return (0);
542}
543
544int
545size(s)
546	register char	*s;
547{
548	register int i = 0;
549
550	while (s && *s++)
551		i++;
552	return (i);
553}
554
555char *
556interp(s)
557	register char *s;
558{
559	static char buf[256];
560	register char *p = buf, c, *q;
561
562	while ((c = *s++)) {
563		for (q = "\nn\rr\tt\ff\033E\bb"; *q; q++)
564			if (*q++ == c) {
565				*p++ = '\\'; *p++ = *q;
566				goto next;
567			}
568		if (c < 040) {
569			*p++ = '^'; *p++ = c + 'A'-1;
570		} else if (c == 0177) {
571			*p++ = '^'; *p++ = '?';
572		} else
573			*p++ = c;
574	next:
575		;
576	}
577	*p = '\0';
578	return (buf);
579}
580
581char *
582ctrl(c)
583	char c;
584{
585	static char s[3];
586
587	if (c < 040 || c == 0177) {
588		s[0] = '^';
589		s[1] = c == 0177 ? '?' : c+'A'-1;
590		s[2] = '\0';
591	} else {
592		s[0] = c;
593		s[1] = '\0';
594	}
595	return (s);
596}
597
598/*
599 * Help command
600 */
601void
602help(c)
603	char c;
604{
605	register esctable_t *p;
606
607	printf("%c\r\n", c);
608	for (p = etable; p->e_char; p++) {
609		if ((p->e_flags&PRIV) && uid)
610			continue;
611		printf("%2s", ctrl(character(value(ESCAPE))));
612		printf("%-2s %c   %s\r\n", ctrl(p->e_char),
613			p->e_flags&EXP ? '*': ' ', p->e_help);
614	}
615}
616
617/*
618 * Set up the "remote" tty's state
619 */
620void
621ttysetup (int speed)
622{
623#if HAVE_TERMIOS
624	struct termios termios;
625	tcgetattr (FD, &termios);
626	if (boolean(value(TAND)))
627		termios.c_iflag = IXOFF;
628	else
629		termios.c_iflag = 0;
630#ifndef _POSIX_SOURCE
631	termios.c_lflag = (PENDIN|ECHOKE|ECHOE);
632#else
633	termios.c_lflag = (PENDIN|ECHOE);
634#endif
635	termios.c_cflag = (CLOCAL|HUPCL|CREAD|CS8);
636	termios.c_ispeed = termios.c_ospeed = speed;
637	tcsetattr (FD, TCSANOW, &termios);
638#else /* HAVE_TERMIOS */
639	unsigned bits = LDECCTQ;
640
641	arg.sg_ispeed = arg.sg_ospeed = speed;
642	arg.sg_flags = RAW;
643	if (boolean(value(TAND)))
644		arg.sg_flags |= TANDEM;
645	ioctl(FD, TIOCSETP, (char *)&arg);
646	ioctl(FD, TIOCLBIS, (char *)&bits);
647#endif /* HAVE_TERMIOS */
648}
649
650/*
651 * Return "simple" name from a file name,
652 * strip leading directories.
653 */
654char *
655sname(s)
656	register char *s;
657{
658	register char *p = s;
659
660	while (*s)
661		if (*s++ == '/')
662			p = s;
663	return (p);
664}
665
666static char partab[0200];
667static int bits8;
668
669/*
670 * Do a write to the remote machine with the correct parity.
671 * We are doing 8 bit wide output, so we just generate a character
672 * with the right parity and output it.
673 */
674void
675xpwrite(fd, buf, n)
676	int fd;
677	char *buf;
678	register int n;
679{
680	register int i;
681	register char *bp;
682
683	bp = buf;
684	if (bits8 == 0)
685		for (i = 0; i < n; i++) {
686			*bp = partab[(*bp) & 0177];
687			bp++;
688		}
689	if (write(fd, buf, n) < 0) {
690		if (errno == EIO)
691			tipabort("Lost carrier.");
692		if (errno == ENODEV)
693			tipabort("tty not available.");
694		tipabort("Something wrong...");
695	}
696}
697
698/*
699 * Build a parity table with appropriate high-order bit.
700 */
701void
702setparity(defparity)
703	char *defparity;
704{
705	register int i, flip, clr, set;
706	char *parity;
707	extern char evenpartab[];
708
709	if (value(PARITY) == NOSTR)
710		value(PARITY) = defparity;
711	parity = value(PARITY);
712	if (equal(parity, "none")) {
713		bits8 = 1;
714		return;
715	}
716	bits8 = 0;
717	flip = 0;
718	clr = 0377;
719	set = 0;
720	if (equal(parity, "odd"))
721		flip = 0200;			/* reverse bit 7 */
722	else if (equal(parity, "zero"))
723		clr = 0177;			/* turn off bit 7 */
724	else if (equal(parity, "one"))
725		set = 0200;			/* turn on bit 7 */
726	else if (!equal(parity, "even")) {
727		(void) fprintf(stderr, "%s: unknown parity value\r\n", parity);
728		(void) fflush(stderr);
729	}
730	for (i = 0; i < 0200; i++)
731		partab[i] = (evenpartab[i] ^ flip) | (set & clr);
732}
733