tip.c revision 50477 
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 50477 1999-08-28 01:08:13Z peter $";
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 <sys/types.h>
62#include <libutil.h>
63#include "tipconf.h"
64#include "tip.h"
65#include "pathnames.h"
66
67/*
68 * Baud rate mapping table
69 */
70#if !HAVE_TERMIOS
71CONST int bauds[] = {
72	0, 50, 75, 110, 134, 150, 200, 300, 600,
73	1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200, -1
74};
75#endif
76
77#if !HAVE_TERMIOS
78int	disc = OTTYDISC;		/* tip normally runs this way */
79#endif
80
81void	intprompt();
82void	timeout();
83void	cleanup();
84void	tipdone();
85char	*sname();
86char	PNbuf[256];			/* This limits the size of a number */
87
88static void usage __P((void));
89void setparity __P((char *));
90void xpwrite __P((int, char *, int));
91char escape __P((void));
92void tipin __P((void));
93int prompt __P((char *, char *, size_t));
94void unraw __P((void));
95void shell_uid __P((void));
96void daemon_uid __P((void));
97void user_uid __P((void));
98int speed __P((int));
99
100void
101main(argc, argv)
102	char *argv[];
103{
104	char *system = NOSTR;
105	register int i;
106	register char *p;
107	char sbuf[12];
108
109	gid = getgid();
110	egid = getegid();
111	uid = getuid();
112	euid = geteuid();
113
114#if INCLUDE_CU_INTERFACE
115	if (equal(sname(argv[0]), "cu")) {
116		cumode = 1;
117		cumain(argc, argv);
118		goto cucommon;
119	}
120#endif /* INCLUDE_CU_INTERFACE */
121
122	if (argc > 4)
123		usage();
124	if (!isatty(0))
125		errx(1, "must be interactive");
126
127	for (; argc > 1; argv++, argc--) {
128		if (argv[1][0] != '-')
129			system = argv[1];
130		else switch (argv[1][1]) {
131
132		case 'v':
133			vflag++;
134			break;
135
136		case '0': case '1': case '2': case '3': case '4':
137		case '5': case '6': case '7': case '8': case '9':
138			BR = atoi(&argv[1][1]);
139			break;
140
141		default:
142			warnx("%s, unknown option", argv[1]);
143			break;
144		}
145	}
146
147	if (system == NOSTR)
148		goto notnumber;
149	if (isalpha(*system))
150		goto notnumber;
151	/*
152	 * System name is really a phone number...
153	 * Copy the number then stomp on the original (in case the number
154	 *	is private, we don't want 'ps' or 'w' to find it).
155	 */
156	if (strlen(system) > sizeof(PNbuf) - 1)
157		errx(1, "phone number too long (max = %d bytes)", sizeof PNbuf - 1);
158	strncpy(PNbuf, system, sizeof(PNbuf) - 1);
159	for (p = system; *p; p++)
160		*p = '\0';
161	PN = PNbuf;
162	(void)snprintf(sbuf, sizeof(sbuf), "tip%ld", BR);
163	system = sbuf;
164
165notnumber:
166	(void)signal(SIGINT, cleanup);
167	(void)signal(SIGQUIT, cleanup);
168	(void)signal(SIGHUP, cleanup);
169	(void)signal(SIGTERM, cleanup);
170	(void)signal(SIGUSR1, tipdone);
171
172	if ((i = hunt(system)) == 0) {
173		printf("all ports busy\n");
174		exit(3);
175	}
176	if (i == -1) {
177		printf("link down\n");
178		(void)uu_unlock(uucplock);
179		exit(3);
180	}
181	setbuf(stdout, NULL);
182	loginit();
183
184	/*
185	 * Kludge, their's no easy way to get the initialization
186	 *   in the right order, so force it here
187	 */
188	if ((PH = getenv("PHONES")) == NOSTR)
189		PH = _PATH_PHONES;
190	vinit();				/* init variables */
191	setparity("even");			/* set the parity table */
192	if ((i = speed(number(value(BAUDRATE)))) == 0) {
193		printf("tip: bad baud rate %d\n", number(value(BAUDRATE)));
194		(void)uu_unlock(uucplock);
195		exit(3);
196	}
197
198	/*
199	 * Now that we have the logfile and the ACU open
200	 *  return to the real uid and gid.  These things will
201	 *  be closed on exit.  Swap real and effective uid's
202	 *  so we can get the original permissions back
203	 *  for removing the uucp lock.
204	 */
205	user_uid();
206
207	/*
208	 * Hardwired connections require the
209	 *  line speed set before they make any transmissions
210	 *  (this is particularly true of things like a DF03-AC)
211	 */
212	if (HW)
213		ttysetup(i);
214	if ((p = connect())) {
215		printf("\07%s\n[EOT]\n", p);
216		daemon_uid();
217		(void)uu_unlock(uucplock);
218		exit(1);
219	}
220	if (!HW)
221		ttysetup(i);
222/* cucommon:*/
223	/*
224	 * From here down the code is shared with
225	 * the "cu" version of tip.
226	 */
227
228#if HAVE_TERMIOS
229	tcgetattr (0, &otermios);
230	ctermios = otermios;
231#ifndef _POSIX_SOURCE
232	ctermios.c_iflag = (IMAXBEL|IXANY|ISTRIP|IXON|BRKINT);
233	ctermios.c_lflag = (PENDIN|IEXTEN|ISIG|ECHOCTL|ECHOE|ECHOKE);
234#else
235	ctermios.c_iflag = (ISTRIP|IXON|BRKINT);
236	ctermios.c_lflag = (PENDIN|IEXTEN|ISIG|ECHOE);
237#endif
238	ctermios.c_cflag = (CLOCAL|HUPCL|CREAD|CS8);
239	ctermios.c_cc[VINTR] = 	ctermios.c_cc[VQUIT] = -1;
240	ctermios.c_cc[VSUSP] = ctermios.c_cc[VDSUSP] = ctermios.c_cc[VDISCARD] =
241		ctermios.c_cc[VLNEXT] = -1;
242#else /* HAVE_TERMIOS */
243	ioctl(0, TIOCGETP, (char *)&defarg);
244	ioctl(0, TIOCGETC, (char *)&defchars);
245	ioctl(0, TIOCGLTC, (char *)&deflchars);
246	ioctl(0, TIOCGETD, (char *)&odisc);
247	arg = defarg;
248	arg.sg_flags = ANYP | CBREAK;
249	tchars = defchars;
250	tchars.t_intrc = tchars.t_quitc = -1;
251	ltchars = deflchars;
252	ltchars.t_suspc = ltchars.t_dsuspc = ltchars.t_flushc
253		= ltchars.t_lnextc = -1;
254#endif /* HAVE_TERMIOS */
255	raw();
256
257	pipe(fildes); pipe(repdes);
258	(void)signal(SIGALRM, timeout);
259
260	/*
261	 * Everything's set up now:
262	 *	connection established (hardwired or dialup)
263	 *	line conditioned (baud rate, mode, etc.)
264	 *	internal data structures (variables)
265	 * so, fork one process for local side and one for remote.
266	 */
267	printf(cumode ? "Connected\r\n" : "\07connected\r\n");
268
269	if (LI != NOSTR && tiplink (LI, 0) != 0) {
270		tipabort ("login failed");
271	}
272
273	if ((pid = fork()))
274		tipin();
275	else
276		tipout();
277	/*NOTREACHED*/
278}
279
280static void
281usage()
282{
283	fprintf(stderr, "usage: tip [-v] [-speed] [system-name]\n");
284	exit(1);
285}
286
287void
288cleanup()
289{
290
291	daemon_uid();
292	(void)uu_unlock(uucplock);
293#if !HAVE_TERMIOS
294	if (odisc)
295		ioctl(0, TIOCSETD, (char *)&odisc);
296#endif
297	exit(0);
298}
299
300void
301tipdone()
302{
303	tipabort("Hangup.");
304}
305/*
306 * Muck with user ID's.  We are setuid to the owner of the lock
307 * directory when we start.  user_uid() reverses real and effective
308 * ID's after startup, to run with the user's permissions.
309 * daemon_uid() switches back to the privileged uid for unlocking.
310 * Finally, to avoid running a shell with the wrong real uid,
311 * shell_uid() sets real and effective uid's to the user's real ID.
312 */
313static int uidswapped;
314
315void
316user_uid()
317{
318	if (uidswapped == 0) {
319		seteuid(uid);
320		uidswapped = 1;
321	}
322}
323
324void
325daemon_uid()
326{
327	if (uidswapped) {
328		seteuid(euid);
329		uidswapped = 0;
330	}
331}
332
333void
334shell_uid()
335{
336	setegid(gid);
337	seteuid(uid);
338}
339
340/*
341 * put the controlling keyboard into raw mode
342 */
343void
344raw ()
345{
346#if HAVE_TERMIOS
347	tcsetattr (0, TCSANOW, &ctermios);
348#else /* HAVE_TERMIOS */
349
350	ioctl(0, TIOCSETP, &arg);
351	ioctl(0, TIOCSETC, &tchars);
352	ioctl(0, TIOCSLTC, &ltchars);
353	ioctl(0, TIOCSETD, (char *)&disc);
354#endif /* HAVE_TERMIOS */
355}
356
357
358/*
359 * return keyboard to normal mode
360 */
361void
362unraw()
363{
364#if HAVE_TERMIOS
365	tcsetattr (0, TCSANOW, &otermios);
366#else /* HAVE_TERMIOS */
367
368	ioctl(0, TIOCSETD, (char *)&odisc);
369	ioctl(0, TIOCSETP, (char *)&defarg);
370	ioctl(0, TIOCSETC, (char *)&defchars);
371	ioctl(0, TIOCSLTC, (char *)&deflchars);
372#endif /* HAVE_TERMIOS */
373}
374
375static	jmp_buf promptbuf;
376
377/*
378 * Print string ``s'', then read a string
379 *  in from the terminal.  Handles signals & allows use of
380 *  normal erase and kill characters.
381 */
382int
383prompt(s, p, sz)
384	char *s;
385	register char *p;
386	size_t sz;
387{
388	register char *b = p;
389	sig_t oint, oquit;
390
391	stoprompt = 0;
392	oint = signal(SIGINT, intprompt);
393	oquit = signal(SIGQUIT, SIG_IGN);
394	unraw();
395	printf("%s", s);
396	if (setjmp(promptbuf) == 0)
397		while ((*p = getchar()) != EOF && *p != '\n' && --sz > 0)
398			p++;
399	*p = '\0';
400
401	raw();
402	(void)signal(SIGINT, oint);
403	(void)signal(SIGQUIT, oquit);
404	return (stoprompt || p == b);
405}
406
407/*
408 * Interrupt service routine during prompting
409 */
410void
411intprompt()
412{
413
414	(void)signal(SIGINT, SIG_IGN);
415	stoprompt = 1;
416	printf("\r\n");
417	longjmp(promptbuf, 1);
418}
419
420/*
421 * ****TIPIN   TIPIN****
422 */
423void
424tipin()
425{
426	int i;
427	char gch, bol = 1;
428
429	/*
430	 * Kinda klugey here...
431	 *   check for scripting being turned on from the .tiprc file,
432	 *   but be careful about just using setscript(), as we may
433	 *   send a SIGEMT before tipout has a chance to set up catching
434	 *   it; so wait a second, then setscript()
435	 */
436	if (boolean(value(SCRIPT))) {
437		sleep(1);
438		setscript();
439	}
440
441	while (1) {
442		i = getchar();
443		if (i == EOF)
444			break;
445		gch = i&0177;
446		if ((gch == character(value(ESCAPE))) && bol) {
447			if (!(gch = escape()))
448				continue;
449		} else if (!cumode && gch == character(value(RAISECHAR))) {
450			boolean(value(RAISE)) = !boolean(value(RAISE));
451			continue;
452		} else if (gch == '\r') {
453			bol = 1;
454			xpwrite(FD, &gch, 1);
455			if (boolean(value(HALFDUPLEX)))
456				printf("\r\n");
457			continue;
458		} else if (!cumode && gch == character(value(FORCE))) {
459			i = getchar();
460			if (i == EOF)
461				break;
462			gch = i & 0177;
463		}
464		bol = any(gch, value(EOL));
465		if (boolean(value(RAISE)) && islower(gch))
466			gch = toupper(gch);
467		xpwrite(FD, &gch, 1);
468		if (boolean(value(HALFDUPLEX)))
469			printf("%c", gch);
470	}
471}
472
473extern esctable_t etable[];
474
475/*
476 * Escape handler --
477 *  called on recognition of ``escapec'' at the beginning of a line
478 */
479char
480escape()
481{
482	register char gch;
483	register esctable_t *p;
484	char c = character(value(ESCAPE));
485	int i;
486
487	i = getchar();
488	if (i == EOF)
489		return 0;
490	gch = (i&0177);
491	for (p = etable; p->e_char; p++)
492		if (p->e_char == gch) {
493			if ((p->e_flags&PRIV) && uid)
494				continue;
495			printf("%s", ctrl(c));
496			(*p->e_func)(gch);
497			return (0);
498		}
499	/* ESCAPE ESCAPE forces ESCAPE */
500	if (c != gch)
501		xpwrite(FD, &c, 1);
502	return (gch);
503}
504
505int
506speed(n)
507	int n;
508{
509#if HAVE_TERMIOS
510	return (n);
511#else
512	register CONST int *p;
513
514	for (p = bauds; *p != -1;  p++)
515		if (*p == n)
516			return (p - bauds);
517	return (NULL);
518#endif
519}
520
521int
522any(c, p)
523	register char c, *p;
524{
525	while (p && *p)
526		if (*p++ == c)
527			return (1);
528	return (0);
529}
530
531int
532size(s)
533	register char	*s;
534{
535	register int i = 0;
536
537	while (s && *s++)
538		i++;
539	return (i);
540}
541
542char *
543interp(s)
544	register char *s;
545{
546	static char buf[256];
547	register char *p = buf, c, *q;
548
549	while ((c = *s++)) {
550		for (q = "\nn\rr\tt\ff\033E\bb"; *q; q++)
551			if (*q++ == c) {
552				*p++ = '\\'; *p++ = *q;
553				goto next;
554			}
555		if (c < 040) {
556			*p++ = '^'; *p++ = c + 'A'-1;
557		} else if (c == 0177) {
558			*p++ = '^'; *p++ = '?';
559		} else
560			*p++ = c;
561	next:
562		;
563	}
564	*p = '\0';
565	return (buf);
566}
567
568char *
569ctrl(c)
570	char c;
571{
572	static char s[3];
573
574	if (c < 040 || c == 0177) {
575		s[0] = '^';
576		s[1] = c == 0177 ? '?' : c+'A'-1;
577		s[2] = '\0';
578	} else {
579		s[0] = c;
580		s[1] = '\0';
581	}
582	return (s);
583}
584
585/*
586 * Help command
587 */
588void
589help(c)
590	char c;
591{
592	register esctable_t *p;
593
594	printf("%c\r\n", c);
595	for (p = etable; p->e_char; p++) {
596		if ((p->e_flags&PRIV) && uid)
597			continue;
598		printf("%2s", ctrl(character(value(ESCAPE))));
599		printf("%-2s %c   %s\r\n", ctrl(p->e_char),
600			p->e_flags&EXP ? '*': ' ', p->e_help);
601	}
602}
603
604/*
605 * Set up the "remote" tty's state
606 */
607void
608ttysetup (int speed)
609{
610#if HAVE_TERMIOS
611	struct termios termios;
612	tcgetattr (FD, &termios);
613	if (boolean(value(TAND)))
614		termios.c_iflag = IXOFF;
615	else
616		termios.c_iflag = 0;
617#ifndef _POSIX_SOURCE
618	termios.c_lflag = (PENDIN|ECHOKE|ECHOE);
619#else
620	termios.c_lflag = (PENDIN|ECHOE);
621#endif
622	termios.c_cflag = (CLOCAL|HUPCL|CREAD|CS8);
623	termios.c_ispeed = termios.c_ospeed = speed;
624	tcsetattr (FD, TCSANOW, &termios);
625#else /* HAVE_TERMIOS */
626	unsigned bits = LDECCTQ;
627
628	arg.sg_ispeed = arg.sg_ospeed = speed;
629	arg.sg_flags = RAW;
630	if (boolean(value(TAND)))
631		arg.sg_flags |= TANDEM;
632	ioctl(FD, TIOCSETP, (char *)&arg);
633	ioctl(FD, TIOCLBIS, (char *)&bits);
634#endif /* HAVE_TERMIOS */
635}
636
637/*
638 * Return "simple" name from a file name,
639 * strip leading directories.
640 */
641char *
642sname(s)
643	register char *s;
644{
645	register char *p = s;
646
647	while (*s)
648		if (*s++ == '/')
649			p = s;
650	return (p);
651}
652
653static char partab[0200];
654static int bits8;
655
656/*
657 * Do a write to the remote machine with the correct parity.
658 * We are doing 8 bit wide output, so we just generate a character
659 * with the right parity and output it.
660 */
661void
662xpwrite(fd, buf, n)
663	int fd;
664	char *buf;
665	register int n;
666{
667	register int i;
668	register char *bp;
669	extern int errno;
670
671	bp = buf;
672	if (bits8 == 0)
673		for (i = 0; i < n; i++) {
674			*bp = partab[(*bp) & 0177];
675			bp++;
676		}
677	if (write(fd, buf, n) < 0) {
678		if (errno == EIO)
679			tipabort("Lost carrier.");
680		if (errno == ENODEV)
681			tipabort("tty not available.");
682		tipabort("Something wrong...");
683	}
684}
685
686/*
687 * Build a parity table with appropriate high-order bit.
688 */
689void
690setparity(defparity)
691	char *defparity;
692{
693	register int i, flip, clr, set;
694	char *parity;
695	extern char evenpartab[];
696
697	if (value(PARITY) == NOSTR)
698		value(PARITY) = defparity;
699	parity = value(PARITY);
700	if (equal(parity, "none")) {
701		bits8 = 1;
702		return;
703	}
704	bits8 = 0;
705	flip = 0;
706	clr = 0377;
707	set = 0;
708	if (equal(parity, "odd"))
709		flip = 0200;			/* reverse bit 7 */
710	else if (equal(parity, "zero"))
711		clr = 0177;			/* turn off bit 7 */
712	else if (equal(parity, "one"))
713		set = 0200;			/* turn on bit 7 */
714	else if (!equal(parity, "even")) {
715		(void) fprintf(stderr, "%s: unknown parity value\r\n", parity);
716		(void) fflush(stderr);
717	}
718	for (i = 0; i < 0200; i++)
719		partab[i] = (evenpartab[i] ^ flip) | (set & clr);
720}
721