xref: /netbsd-src/libexec/getty/main.c (revision 7cc2f76925f078d01ddc9e640a98f4ccfc9f8c3b)
1 /*	$NetBSD: main.c,v 1.34 2000/10/08 16:08:56 bjh21 Exp $	*/
2 
3 /*-
4  * Copyright (c) 1980, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 
38 #ifndef lint
39 __COPYRIGHT("@(#) Copyright (c) 1980, 1993\n\
40 	The Regents of the University of California.  All rights reserved.\n");
41 #endif /* not lint */
42 
43 #ifndef lint
44 #if 0
45 static char sccsid[] = "from: @(#)main.c	8.1 (Berkeley) 6/20/93";
46 #else
47 __RCSID("$NetBSD: main.c,v 1.34 2000/10/08 16:08:56 bjh21 Exp $");
48 #endif
49 #endif /* not lint */
50 
51 #include <sys/param.h>
52 #include <sys/stat.h>
53 #include <termios.h>
54 #include <sys/ioctl.h>
55 #include <sys/resource.h>
56 #include <sys/utsname.h>
57 
58 #include <errno.h>
59 #include <fcntl.h>
60 #include <time.h>
61 #include <ctype.h>
62 #include <fcntl.h>
63 #include <pwd.h>
64 #include <setjmp.h>
65 #include <signal.h>
66 #include <stdlib.h>
67 #include <string.h>
68 #include <syslog.h>
69 #include <time.h>
70 #include <unistd.h>
71 #include <util.h>
72 #include <limits.h>
73 
74 #include "gettytab.h"
75 #include "pathnames.h"
76 #include "extern.h"
77 
78 extern char *__progname;
79 
80 /*
81  * Set the amount of running time that getty should accumulate
82  * before deciding that something is wrong and exit.
83  */
84 #define GETTY_TIMEOUT	60 /* seconds */
85 
86 /* defines for auto detection of incoming PPP calls (->PAP/CHAP) */
87 
88 #define PPP_FRAME           0x7e  /* PPP Framing character */
89 #define PPP_STATION         0xff  /* "All Station" character */
90 #define PPP_ESCAPE          0x7d  /* Escape Character */
91 #define PPP_CONTROL         0x03  /* PPP Control Field */
92 #define PPP_CONTROL_ESCAPED 0x23  /* PPP Control Field, escaped */
93 #define PPP_LCP_HI          0xc0  /* LCP protocol - high byte */
94 #define PPP_LCP_LOW         0x21  /* LCP protocol - low byte */
95 
96 struct termios tmode, omode;
97 
98 int crmod, digit, lower, upper;
99 
100 char	hostname[MAXHOSTNAMELEN + 1];
101 struct	utsname kerninfo;
102 char	name[LOGIN_NAME_MAX];
103 char	dev[] = _PATH_DEV;
104 char	ttyn[32];
105 char	lockfile[512];
106 uid_t	ttyowner;
107 
108 #define	OBUFSIZ		128
109 #define	TABBUFSIZ	512
110 
111 char	defent[TABBUFSIZ];
112 char	tabent[TABBUFSIZ];
113 
114 char	*env[128];
115 
116 char partab[] = {
117 	0001,0201,0201,0001,0201,0001,0001,0201,
118 	0202,0004,0003,0205,0005,0206,0201,0001,
119 	0201,0001,0001,0201,0001,0201,0201,0001,
120 	0001,0201,0201,0001,0201,0001,0001,0201,
121 	0200,0000,0000,0200,0000,0200,0200,0000,
122 	0000,0200,0200,0000,0200,0000,0000,0200,
123 	0000,0200,0200,0000,0200,0000,0000,0200,
124 	0200,0000,0000,0200,0000,0200,0200,0000,
125 	0200,0000,0000,0200,0000,0200,0200,0000,
126 	0000,0200,0200,0000,0200,0000,0000,0200,
127 	0000,0200,0200,0000,0200,0000,0000,0200,
128 	0200,0000,0000,0200,0000,0200,0200,0000,
129 	0000,0200,0200,0000,0200,0000,0000,0200,
130 	0200,0000,0000,0200,0000,0200,0200,0000,
131 	0200,0000,0000,0200,0000,0200,0200,0000,
132 	0000,0200,0200,0000,0200,0000,0000,0201
133 };
134 
135 #define	ERASE	tmode.c_cc[VERASE]
136 #define	KILL	tmode.c_cc[VKILL]
137 #define	EOT	tmode.c_cc[VEOF]
138 
139 static void	dingdong __P((int));
140 static void	interrupt __P((int));
141 void		timeoverrun __P((int));
142 
143 jmp_buf timeout;
144 
145 static void
146 dingdong(signo)
147 	int signo;
148 {
149 
150 	alarm(0);
151 	signal(SIGALRM, SIG_DFL);
152 	longjmp(timeout, 1);
153 }
154 
155 jmp_buf	intrupt;
156 
157 static void
158 interrupt(signo)
159 	int signo;
160 {
161 
162 	signal(SIGINT, interrupt);
163 	longjmp(intrupt, 1);
164 }
165 
166 /*
167  * Action to take when getty is running too long.
168  */
169 void
170 timeoverrun(signo)
171 	int signo;
172 {
173 
174 	syslog(LOG_ERR, "getty exiting due to excessive running time");
175 	exit(1);
176 }
177 
178 int		main __P((int, char **));
179 static int	getname __P((void));
180 static void	oflush __P((void));
181 static void	prompt __P((void));
182 static void	putchr __P((int));
183 static void	putf __P((const char *));
184 static void	putpad __P((const char *));
185 static void	xputs __P((const char *));
186 
187 int
188 main(argc, argv)
189 	int argc;
190 	char *argv[];
191 {
192 	extern char **environ;
193 	char *tname;
194 	int repcnt = 0, failopenlogged = 0, uugetty = 0, first_time = 1;
195 	struct rlimit limit;
196 	struct passwd *pw;
197         int rval;
198 
199 #ifdef __GNUC__
200 	(void)&tname;		/* XXX gcc -Wall */
201 #endif
202 
203 	signal(SIGINT, SIG_IGN);
204 /*
205 	signal(SIGQUIT, SIG_DFL);
206 */
207 	openlog("getty", LOG_ODELAY|LOG_PID, LOG_AUTH);
208 	gethostname(hostname, sizeof(hostname));
209 	hostname[sizeof(hostname) - 1] = '\0';
210 	if (hostname[0] == '\0')
211 		strcpy(hostname, "Amnesiac");
212 	uname(&kerninfo);
213 
214 	if (__progname[0] == 'u' && __progname[1] == 'u')
215 		uugetty = 1;
216 
217 	/*
218 	 * Find id of uucp login (if present) so we can chown tty properly.
219 	 */
220 	if (uugetty && (pw = getpwnam("uucp")))
221 		ttyowner = pw->pw_uid;
222 	else
223 		ttyowner = 0;
224 
225 	/*
226 	 * Limit running time to deal with broken or dead lines.
227 	 */
228 	(void)signal(SIGXCPU, timeoverrun);
229 	limit.rlim_max = RLIM_INFINITY;
230 	limit.rlim_cur = GETTY_TIMEOUT;
231 	(void)setrlimit(RLIMIT_CPU, &limit);
232 
233 	/*
234 	 * The following is a work around for vhangup interactions
235 	 * which cause great problems getting window systems started.
236 	 * If the tty line is "-", we do the old style getty presuming
237 	 * that the file descriptors are already set up for us.
238 	 * J. Gettys - MIT Project Athena.
239 	 */
240 	if (argc <= 2 || strcmp(argv[2], "-") == 0) {
241 	    strlcpy(ttyn, ttyname(0), sizeof(ttyn));
242 	}
243 	else {
244 	    int i;
245 
246 	    strlcpy(ttyn, dev, sizeof(ttyn));
247 	    strlcat(ttyn, argv[2], sizeof(ttyn));
248 
249 	    if (uugetty)  {
250 		chown(ttyn, ttyowner, 0);
251 		strcpy(lockfile, _PATH_LOCK);
252 		strlcat(lockfile, argv[2], sizeof(lockfile));
253 		/* wait for lockfiles to go away before we try to open */
254 		if ( pidlock(lockfile, 0, 0, 0) != 0 )  {
255 		    syslog(LOG_ERR, "%s: can't create lockfile", ttyn);
256 		    exit(1);
257 		}
258 		unlink(lockfile);
259 	    }
260 	    if (strcmp(argv[0], "+") != 0) {
261 		chown(ttyn, ttyowner, 0);
262 		chmod(ttyn, 0600);
263 		revoke(ttyn);
264 		if (ttyaction(ttyn, "getty", "root"))
265 			syslog(LOG_ERR,"%s: ttyaction failed", ttyn);
266 		/*
267 		 * Delay the open so DTR stays down long enough to be detected.
268 		 */
269 		sleep(2);
270 		while ((i = open(ttyn, O_RDWR)) == -1) {
271 			if ((repcnt % 10 == 0) &&
272 			    (errno != ENXIO || !failopenlogged)) {
273 				syslog(LOG_ERR, "%s: %m", ttyn);
274 				closelog();
275 				failopenlogged = 1;
276 			}
277 			repcnt++;
278 			sleep(60);
279 		}
280 		if (uugetty && pidlock(lockfile, 0, 0, 0) != 0)  {
281 			syslog(LOG_ERR, "%s: can't create lockfile", ttyn);
282 			exit(1);
283 		}
284 		(void) chown(lockfile, ttyowner, 0);
285 		login_tty(i);
286 	    }
287 	}
288 
289 	/* Start with default tty settings */
290 	if (tcgetattr(0, &tmode) < 0) {
291 		syslog(LOG_ERR, "%s: %m", ttyn);
292 		exit(1);
293 	}
294 	omode = tmode;
295 
296 	gettable("default", defent);
297 	gendefaults();
298 	tname = "default";
299 	if (argc > 1)
300 		tname = argv[1];
301 	for (;;) {
302 		int off;
303 
304 		gettable(tname, tabent);
305 		if (OPset || EPset || APset)
306 			APset++, OPset++, EPset++;
307 		setdefaults();
308 		off = 0;
309 		(void)tcflush(0, TCIOFLUSH);	/* clear out the crap */
310 		ioctl(0, FIONBIO, &off);	/* turn off non-blocking mode */
311 		ioctl(0, FIOASYNC, &off);	/* ditto for async mode */
312 
313 		if (IS)
314 			cfsetispeed(&tmode, IS);
315 		else if (SP)
316 			cfsetispeed(&tmode, SP);
317 		if (OS)
318 			cfsetospeed(&tmode, OS);
319 		else if (SP)
320 			cfsetospeed(&tmode, SP);
321 		setflags(0);
322 		setchars();
323 		if (tcsetattr(0, TCSANOW, &tmode) < 0) {
324 			syslog(LOG_ERR, "%s: %m", ttyn);
325 			exit(1);
326 		}
327 		if (AB) {
328 			tname = autobaud();
329 			continue;
330 		}
331 		if (PS) {
332 			tname = portselector();
333 			continue;
334 		}
335 		if (CL && *CL)
336 			putpad(CL);
337 		edithost(HE);
338 
339                 /*
340                  * If this is the first time through this, and an
341                  * issue file has been given, then send it.
342                  */
343 		if (first_time != 0 && IF != NULL) {
344 			char buf[_POSIX2_LINE_MAX];
345 			FILE *fd;
346 
347 			if ((fd = fopen(IF, "r")) != NULL) {
348 				while (fgets(buf, sizeof(buf) - 1, fd) != NULL)
349 					putf(buf);
350 				fclose(fd);
351 			}
352 		}
353 		first_time = 0;
354 
355 		if (IM && *IM)
356 			putf(IM);
357 		oflush();
358 		if (setjmp(timeout)) {
359 			tmode.c_ispeed = tmode.c_ospeed = 0;
360 			(void)tcsetattr(0, TCSANOW, &tmode);
361 			exit(1);
362 		}
363 		if (TO) {
364 			signal(SIGALRM, dingdong);
365 			alarm(TO);
366 		}
367 		if (AL) {
368 			const char *p = AL;
369 			char *q = name;
370 
371 			while (*p && q < &name[sizeof name - 1]) {
372 				if (isupper(*p))
373 					upper = 1;
374 				else if (islower(*p))
375 					lower = 1;
376 				else if (isdigit(*p))
377 					digit++;
378 				*q++ = *p++;
379 			}
380 		} else if ((rval = getname()) == 2) {
381 		        execle(PP, "ppplogin", ttyn, (char *) 0, env);
382 		        syslog(LOG_ERR, "%s: %m", PP);
383 		        exit(1);
384 		}
385 
386 		if (rval || AL) {
387 			int i;
388 
389 			oflush();
390 			alarm(0);
391 			signal(SIGALRM, SIG_DFL);
392 			if (name[0] == '-') {
393 				xputs("user names may not start with '-'.");
394 				continue;
395 			}
396 			if (!(upper || lower || digit))
397 				continue;
398 			setflags(2);
399 			if (crmod) {
400 				tmode.c_iflag |= ICRNL;
401 				tmode.c_oflag |= ONLCR;
402 			}
403 #if XXX
404 			if (upper || UC)
405 				tmode.sg_flags |= LCASE;
406 			if (lower || LC)
407 				tmode.sg_flags &= ~LCASE;
408 #endif
409 			if (tcsetattr(0, TCSANOW, &tmode) < 0) {
410 				syslog(LOG_ERR, "%s: %m", ttyn);
411 				exit(1);
412 			}
413 			signal(SIGINT, SIG_DFL);
414 			for (i = 0; environ[i] != (char *)0; i++)
415 				env[i] = environ[i];
416 			makeenv(&env[i]);
417 
418 			limit.rlim_max = RLIM_INFINITY;
419 			limit.rlim_cur = RLIM_INFINITY;
420 			(void)setrlimit(RLIMIT_CPU, &limit);
421 			execle(LO, "login", AL ? "-fp" : "-p", "--", name,
422 			    (char *)0, env);
423 			syslog(LOG_ERR, "%s: %m", LO);
424 			exit(1);
425 		}
426 		alarm(0);
427 		signal(SIGALRM, SIG_DFL);
428 		signal(SIGINT, SIG_IGN);
429 		if (NX && *NX)
430 			tname = NX;
431 		unlink(lockfile);
432 	}
433 }
434 
435 static int
436 getname()
437 {
438 	int c;
439 	char *np;
440 	unsigned char cs;
441 	int ppp_state, ppp_connection;
442 
443 	/*
444 	 * Interrupt may happen if we use CBREAK mode
445 	 */
446 	if (setjmp(intrupt)) {
447 		signal(SIGINT, SIG_IGN);
448 		return (0);
449 	}
450 	signal(SIGINT, interrupt);
451 	setflags(1);
452 	prompt();
453 	if (PF > 0) {
454 		oflush();
455 		sleep(PF);
456 		PF = 0;
457 	}
458 	if (tcsetattr(0, TCSANOW, &tmode) < 0) {
459 		syslog(LOG_ERR, "%s: %m", ttyn);
460 		exit(1);
461 	}
462 	crmod = digit = lower = upper = 0;
463         ppp_state = ppp_connection = 0;
464 	np = name;
465 	for (;;) {
466 		oflush();
467 		if (read(STDIN_FILENO, &cs, 1) <= 0)
468 			exit(0);
469 		if ((c = cs&0177) == 0)
470 			return (0);
471 
472 		/*
473 		 * PPP detection state machine..
474 		 * Look for sequences:
475 		 * PPP_FRAME, PPP_STATION, PPP_ESCAPE, PPP_CONTROL_ESCAPED or
476 		 * PPP_FRAME, PPP_STATION, PPP_CONTROL (deviant from RFC)
477 		 * See RFC1662.
478 		 * Derived from code from Michael Hancock <michaelh@cet.co.jp>
479 		 * and Erik 'PPP' Olson <eriko@wrq.com>
480 		 */
481 		if (PP && cs == PPP_FRAME) {
482 			ppp_state = 1;
483 		} else if (ppp_state == 1 && cs == PPP_STATION) {
484 			ppp_state = 2;
485 		} else if (ppp_state == 2 && cs == PPP_ESCAPE) {
486 			ppp_state = 3;
487 		} else if ((ppp_state == 2 && cs == PPP_CONTROL) ||
488 		    (ppp_state == 3 && cs == PPP_CONTROL_ESCAPED)) {
489 			ppp_state = 4;
490 		} else if (ppp_state == 4 && cs == PPP_LCP_HI) {
491 			ppp_state = 5;
492 		} else if (ppp_state == 5 && cs == PPP_LCP_LOW) {
493 			ppp_connection = 1;
494 			break;
495 		} else {
496 			ppp_state = 0;
497 		}
498 
499 		if (c == EOT)
500 			exit(1);
501 		if (c == '\r' || c == '\n' ||
502 		    np >= &name[LOGIN_NAME_MAX - 1]) {
503 			*np = '\0';
504 			putf("\r\n");
505 			break;
506 		}
507 		if (islower(c))
508 			lower = 1;
509 		else if (isupper(c))
510 			upper = 1;
511 		else if (c == ERASE || c == '#' || c == '\b') {
512 			if (np > name) {
513 				np--;
514 				if (cfgetospeed(&tmode) >= 1200)
515 					xputs("\b \b");
516 				else
517 					putchr(cs);
518 			}
519 			continue;
520 		} else if (c == KILL || c == '@') {
521 			putchr(cs);
522 			putchr('\r');
523 			if (cfgetospeed(&tmode) < 1200)
524 				putchr('\n');
525 			/* this is the way they do it down under ... */
526 			else if (np > name)
527 				xputs(
528 				    "                                     \r");
529 			prompt();
530 			np = name;
531 			continue;
532 		} else if (isdigit(c))
533 			digit++;
534 		if (IG && (c <= ' ' || c > 0176))
535 			continue;
536 		*np++ = c;
537 		putchr(cs);
538 	}
539 	signal(SIGINT, SIG_IGN);
540 	*np = 0;
541 	if (c == '\r')
542 		crmod = 1;
543 	if ((upper && !lower && !LC) || UC)
544 		for (np = name; *np; np++)
545 			if (isupper(*np))
546 				*np = tolower(*np);
547 	return (1 + ppp_connection);
548 }
549 
550 static void
551 putpad(s)
552 	const char *s;
553 {
554 	int pad = 0;
555 	speed_t ospeed = cfgetospeed(&tmode);
556 
557 	if (isdigit(*s)) {
558 		while (isdigit(*s)) {
559 			pad *= 10;
560 			pad += *s++ - '0';
561 		}
562 		pad *= 10;
563 		if (*s == '.' && isdigit(s[1])) {
564 			pad += s[1] - '0';
565 			s += 2;
566 		}
567 	}
568 
569 	xputs(s);
570 	/*
571 	 * If no delay needed, or output speed is
572 	 * not comprehensible, then don't try to delay.
573 	 */
574 	if (pad == 0 || ospeed <= 0)
575 		return;
576 
577 	/*
578 	 * Round up by a half a character frame, and then do the delay.
579 	 * Too bad there are no user program accessible programmed delays.
580 	 * Transmitting pad characters slows many terminals down and also
581 	 * loads the system.
582 	 */
583 	pad = (pad * ospeed + 50000) / 100000;
584 	while (pad--)
585 		putchr(*PC);
586 }
587 
588 static void
589 xputs(s)
590 	const char *s;
591 {
592 	while (*s)
593 		putchr(*s++);
594 }
595 
596 char	outbuf[OBUFSIZ];
597 int	obufcnt = 0;
598 
599 static void
600 putchr(cc)
601 	int cc;
602 {
603 	char c;
604 
605 	c = cc;
606 	if (!NP) {
607 		c |= partab[c&0177] & 0200;
608 		if (OP)
609 			c ^= 0200;
610 	}
611 	if (!UB) {
612 		outbuf[obufcnt++] = c;
613 		if (obufcnt >= OBUFSIZ)
614 			oflush();
615 	} else
616 		write(STDOUT_FILENO, &c, 1);
617 }
618 
619 static void
620 oflush()
621 {
622 	if (obufcnt)
623 		write(STDOUT_FILENO, outbuf, obufcnt);
624 	obufcnt = 0;
625 }
626 
627 static void
628 prompt()
629 {
630 
631 	putf(LM);
632 	if (CO)
633 		putchr('\n');
634 }
635 
636 static void
637 putf(cp)
638 	const char *cp;
639 {
640 	extern char editedhost[];
641 	time_t t;
642 	char *slash, db[100];
643 
644 	while (*cp) {
645 		if (*cp != '%') {
646 			putchr(*cp++);
647 			continue;
648 		}
649 		switch (*++cp) {
650 
651 		case 't':
652 			slash = strrchr(ttyn, '/');
653 			if (slash == NULL)
654 				xputs(ttyn);
655 			else
656 				xputs(&slash[1]);
657 			break;
658 
659 		case 'h':
660 			xputs(editedhost);
661 			break;
662 
663 		case 'd':
664 			(void)time(&t);
665 			(void)strftime(db, sizeof(db),
666 			    /* SCCS eats %M% */
667 			    "%l:%M" "%p on %A, %d %B %Y", localtime(&t));
668 			xputs(db);
669 			break;
670 
671 		case 's':
672 			xputs(kerninfo.sysname);
673 			break;
674 
675 		case 'm':
676 			xputs(kerninfo.machine);
677 			break;
678 
679 		case 'r':
680 			xputs(kerninfo.release);
681 			break;
682 
683 		case 'v':
684 			xputs(kerninfo.version);
685 			break;
686 
687 		case '%':
688 			putchr('%');
689 			break;
690 		}
691 		if (*cp)
692 			cp++;
693 	}
694 }
695