2 * Copyright (c) 1988 Regents of the University of California.
5 * This code is derived from software contributed to Berkeley by
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * @(#) Copyright (c) 1988 Regents of the University of California. All rights reserved.
37 * @(#)slattach.c 4.6 (Berkeley) 6/1/90
38 * $FreeBSD: src/sbin/slattach/slattach.c,v 1.36 1999/08/28 00:14:25 peter Exp $
39 * $DragonFly: src/sbin/slattach/slattach.c,v 1.6 2005/02/02 07:59:48 cpressey Exp $
42 #include <sys/types.h>
43 #include <sys/ioctl.h>
44 #include <sys/socket.h>
61 #define DEFAULT_BAUD 9600
63 static void sighup_handler(int); /* SIGHUP handler */
64 static void sigint_handler(int); /* SIGINT handler */
65 static void sigterm_handler(int); /* SIGTERM handler */
66 static void sigurg_handler(int); /* SIGURG handler */
67 static void exit_handler(int); /* run exit_cmd iff specified upon exit. */
68 static void setup_line(int); /* configure terminal settings */
69 static void slip_discipline(void); /* switch to slip line discipline */
70 static void configure_network(void); /* configure slip interface */
71 static void acquire_line(void); /* get tty device as controlling terminal */
72 static void usage(void);
75 char *dev = (char *)0; /* path name of the tty (e.g. /dev/tty01) */
76 char *dvname; /* basename of dev */
77 int locked = 0; /* uucp lock active */
78 int flow_control = 0; /* non-zero to enable hardware flow control. */
79 int modem_control = HUPCL; /* !CLOCAL+HUPCL iff we watch carrier. */
80 int comstate; /* TIOCMGET current state of serial driver */
81 int redial_on_startup = 0; /* iff non-zero execute redial_cmd on startup */
82 speed_t speed = DEFAULT_BAUD; /* baud rate of tty */
83 int slflags = 0; /* compression flags */
84 int unit = -1; /* slip device unit number */
85 int foreground = 0; /* act as demon if zero, else don't fork. */
86 int keepal = 0; /* keepalive timeout */
87 int outfill = 0; /* outfill timeout */
88 int sl_unit = -1; /* unit number */
89 int uucp_lock = 0; /* do uucp locking */
90 int exiting = 0; /* already running exit_handler */
92 struct termios tty; /* tty configuration/state */
94 char tty_path[32]; /* path name of the tty (e.g. /dev/tty01) */
95 char pidfilename[40]; /* e.g. /var/run/slattach.tty01.pid */
96 char *redial_cmd = 0; /* command to exec upon shutdown. */
97 char *config_cmd = 0; /* command to exec if slip unit changes. */
98 char *exit_cmd = 0; /* command to exec before exiting. */
103 fprintf(stderr, "%s\n%s\n",
104 "usage: slattach [-acfhlnz] [-e command] [-r command] [-s speed] [-u command]",
105 " [-L] [-K timeout] [-O timeout] [-S unit] device");
106 /* do not exit here */
110 main(int argc, char **argv)
114 while ((option = getopt(argc, argv, "ace:fhlnr:s:u:zLK:O:S:")) != -1) {
117 slflags |= IFF_LINK2;
118 slflags &= ~IFF_LINK0;
121 slflags |= IFF_LINK0;
122 slflags &= ~IFF_LINK2;
125 exit_cmd = (char*) strdup (optarg);
131 flow_control |= CRTSCTS;
134 modem_control = CLOCAL; /* clear HUPCL too */
137 slflags |= IFF_LINK1;
140 redial_cmd = (char*) strdup (optarg);
143 speed = atoi(optarg);
146 config_cmd = (char*) strdup (optarg);
149 redial_on_startup = 1;
155 keepal = atoi(optarg);
158 outfill = atoi(optarg);
161 sl_unit = atoi(optarg);
170 if (optind == argc - 1)
173 if (optind < (argc - 1))
174 warnx("too many args, first='%s'", argv[optind]);
175 if (optind > (argc - 1))
176 warnx("not enough args");
177 if (dev == (char *)0) {
181 if (strncmp(_PATH_DEV, dev, sizeof(_PATH_DEV) - 1)) {
182 strcpy(tty_path, _PATH_DEV);
183 strcat(tty_path, "/");
184 strncat(tty_path, dev, 10);
187 dvname = strrchr(dev, '/'); /* always succeeds */
188 dvname++; /* trailing tty pathname component */
189 snprintf(pidfilename, sizeof(pidfilename),
190 "%sslattach.%s.pid", _PATH_VARRUN, dvname);
191 printf("%s\n",pidfilename);
194 daemon(0,0); /* fork, setsid, chdir /, and close std*. */
195 /* daemon() closed stderr, so log errors from here on. */
196 openlog("slattach",LOG_CONS|LOG_PID,LOG_DAEMON);
198 acquire_line(); /* get tty device as controlling terminal */
199 setup_line(0); /* configure for slip line discipline */
200 slip_discipline(); /* switch to slip line discipline */
202 /* upon INT log a timestamp and exit. */
203 if (signal(SIGINT,sigint_handler) == SIG_ERR)
204 syslog(LOG_NOTICE,"cannot install SIGINT handler: %m");
205 /* upon TERM log a timestamp and exit. */
206 if (signal(SIGTERM,sigterm_handler) == SIG_ERR)
207 syslog(LOG_NOTICE,"cannot install SIGTERM handler: %m");
208 /* upon HUP redial and reconnect. */
209 if (signal(SIGHUP,sighup_handler) == SIG_ERR)
210 syslog(LOG_NOTICE,"cannot install SIGHUP handler: %m");
212 if (redial_on_startup)
214 else if (!(modem_control & CLOCAL)) {
215 if (ioctl(fd, TIOCMGET, &comstate) < 0)
216 syslog(LOG_NOTICE,"cannot get carrier state: %m");
217 if (!(comstate & TIOCM_CD)) { /* check for carrier */
218 /* force a redial if no carrier */
219 kill (getpid(), SIGHUP);
223 configure_network(); /* configure the network if needed. */
232 /* Close all FDs, fork, reopen tty port as 0-2, and make it the
233 controlling terminal for our process group. */
237 int ttydisc = TTYDISC;
241 /* reset to tty discipline */
242 if (fd >= 0 && ioctl(fd, TIOCSETD, &ttydisc) < 0) {
243 syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
247 close(STDIN_FILENO); /* close FDs before forking. */
248 close(STDOUT_FILENO);
249 close(STDERR_FILENO);
253 signal(SIGHUP, SIG_IGN); /* ignore HUP signal when parent dies. */
254 if (daemon(0,0)) { /* fork, setsid, chdir /, and close std*. */
255 syslog(LOG_ERR, "daemon(0,0): %m");
259 while (getppid () != 1)
260 sleep (1); /* Wait for parent to die. */
262 /* create PID file */
263 if((pid_file = fopen(pidfilename, "w"))) {
264 fprintf(pid_file, "%ld\n", (long)getpid());
268 if (signal(SIGHUP,sighup_handler) == SIG_ERR) /* Re-enable HUP signal */
269 syslog(LOG_NOTICE,"cannot install SIGHUP handler: %m");
272 /* unlock not needed here, always re-lock with new pid */
274 if ((res = uu_lock(dvname)) != UU_LOCK_OK) {
275 if (res != UU_LOCK_INUSE)
276 syslog(LOG_ERR, "uu_lock: %s", uu_lockerr(res));
277 syslog(LOG_ERR, "can't lock %s", dev);
283 if ((fd = open(dev, O_RDWR | O_NONBLOCK, 0)) < 0) {
284 syslog(LOG_ERR, "open(%s) %m", dev);
287 /* Turn off O_NONBLOCK for dumb redialers, if any. */
288 if ((oflags = fcntl(fd, F_GETFL)) == -1) {
289 syslog(LOG_ERR, "fcntl(F_GETFL) failed: %m");
292 if (fcntl(fd, F_SETFL, oflags & ~O_NONBLOCK) == -1) {
293 syslog(LOG_ERR, "fcntl(F_SETFL) failed: %m");
296 dup2(fd, STDIN_FILENO);
297 dup2(fd, STDOUT_FILENO);
298 dup2(fd, STDERR_FILENO);
303 /* acquire the serial line as a controlling terminal. */
304 if (ioctl(fd, TIOCSCTTY, 0) < 0) {
305 syslog(LOG_ERR,"ioctl(TIOCSCTTY): %m");
308 /* Make us the foreground process group associated with the
309 slip line which is our controlling terminal. */
310 if (tcsetpgrp(fd, getpid()) < 0)
311 syslog(LOG_NOTICE,"tcsetpgrp failed: %m");
314 /* Set the tty flags and set DTR. */
315 /* Call as setup_line(CLOCAL) to force clocal assertion. */
317 setup_line(int cflag)
319 tty.c_lflag = tty.c_iflag = tty.c_oflag = 0;
320 tty.c_cflag = CREAD | CS8 | flow_control | modem_control | cflag;
321 cfsetispeed(&tty, speed);
322 cfsetospeed(&tty, speed);
323 /* set the line speed and flow control */
324 if (tcsetattr(fd, TCSAFLUSH, &tty) < 0) {
325 syslog(LOG_ERR, "tcsetattr(TCSAFLUSH): %m");
328 /* set data terminal ready */
329 if (ioctl(fd, TIOCSDTR) < 0) {
330 syslog(LOG_ERR, "ioctl(TIOCSDTR): %m");
335 /* Put the line in slip discipline. */
337 slip_discipline(void)
340 int slipdisc = SLIPDISC;
341 int s, tmp_unit = -1;
343 /* Switch to slip line discipline. */
344 if (ioctl(fd, TIOCSETD, &slipdisc) < 0) {
345 syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
349 if (sl_unit >= 0 && ioctl(fd, SLIOCSUNIT, &sl_unit) < 0) {
350 syslog(LOG_ERR, "ioctl(SLIOCSUNIT): %m");
354 /* find out what unit number we were assigned */
355 if (ioctl(fd, SLIOCGUNIT, (caddr_t)&tmp_unit) < 0) {
356 syslog(LOG_ERR, "ioctl(SLIOCGUNIT): %m");
361 syslog(LOG_ERR, "bad unit (%d) from ioctl(SLIOCGUNIT)",tmp_unit);
366 signal(SIGURG, sigurg_handler);
367 if (ioctl(fd, SLIOCSKEEPAL, &keepal) < 0) {
368 syslog(LOG_ERR, "ioctl(SLIOCSKEEPAL): %m");
372 if (outfill > 0 && ioctl(fd, SLIOCSOUTFILL, &outfill) < 0) {
373 syslog(LOG_ERR, "ioctl(SLIOCSOUTFILL): %m");
377 /* open a socket as the handle to the interface */
378 s = socket(AF_INET, SOCK_DGRAM, 0);
380 syslog(LOG_ERR, "socket: %m");
383 sprintf(ifr.ifr_name, "sl%d", tmp_unit);
385 /* get the flags for the interface */
386 if (ioctl(s, SIOCGIFFLAGS, (caddr_t)&ifr) < 0) {
387 syslog(LOG_ERR, "ioctl (SIOCGIFFLAGS): %m");
391 /* Assert any compression or no-icmp flags. */
392 #define SLMASK (~(IFF_LINK0 | IFF_LINK1 | IFF_LINK2))
393 ifr.ifr_flags &= SLMASK;
394 ifr.ifr_flags |= slflags;
395 if (ioctl(s, SIOCSIFFLAGS, (caddr_t)&ifr) < 0) {
396 syslog(LOG_ERR, "ioctl (SIOCSIFFLAGS): %m");
402 /* configure the interface, e.g. by passing the unit number to a script. */
404 configure_network(void)
408 /* find out what unit number we were assigned */
409 if (ioctl(fd, SLIOCGUNIT, (caddr_t)&new_unit) < 0) {
410 syslog(LOG_ERR, "ioctl(SLIOCGUNIT): %m");
413 /* iff the unit number changes either invoke config_cmd or punt. */
416 s = (char*) malloc(strlen(config_cmd) + 32);
418 syslog(LOG_ERR, "malloc failed");
421 sprintf (s, "%s %d %d", config_cmd, unit, new_unit);
422 syslog(LOG_NOTICE, "configuring %s (sl%d):", dev, unit);
423 syslog(LOG_NOTICE, " '%s'", s);
428 /* don't compare unit numbers if this is the first time to attach. */
431 if (new_unit != unit) {
433 "slip unit changed from sl%d to sl%d, but no -u CMD was specified!",
437 syslog(LOG_NOTICE,"sl%d connected to %s at %d baud",unit,dev,speed);
441 /* sighup_handler() is invoked when carrier drops, eg. before redial. */
443 sighup_handler(int signo __unused)
447 if (redial_cmd == NULL) {
448 syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); exiting", dev, unit);
452 /* invoke a shell for redial_cmd or punt. */
453 if (*redial_cmd) { /* Non-empty redial command */
454 syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); running '%s'",
455 dev, unit, redial_cmd);
456 acquire_line(); /* reopen dead line */
460 uu_unlock(dvname); /* for redial */
463 if (system(redial_cmd))
467 if ((res = uu_lock(dvname)) != UU_LOCK_OK) {
468 if (res != UU_LOCK_INUSE)
469 syslog(LOG_ERR, "uu_lock: %s", uu_lockerr(res));
470 syslog(LOG_ERR, "can't relock %s after %s, aborting",
476 /* Now check again for carrier (dial command is done): */
477 if (!(modem_control & CLOCAL)) {
478 tty.c_cflag &= ~CLOCAL;
479 if (tcsetattr(fd, TCSAFLUSH, &tty) < 0) {
480 syslog(LOG_ERR, "tcsetattr(TCSAFLUSH): %m");
483 ioctl(fd, TIOCMGET, &comstate);
484 if (!(comstate & TIOCM_CD)) { /* check for carrier */
485 /* force a redial if no carrier */
490 } else { /* Empty redial command */
491 syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); reestablish connection",
493 acquire_line(); /* reopen dead line */
494 setup_line(0); /* restore ospeed from hangup (B0) */
495 /* If modem control, just wait for carrier before attaching.
496 If no modem control, just fall through immediately. */
497 if (!(modem_control & CLOCAL)) {
500 syslog(LOG_NOTICE, "waiting for carrier on %s (sl%d)",
502 /* Now wait for carrier before attaching line. */
503 /* We must poll since CLOCAL prevents signal. */
506 ioctl(fd, TIOCMGET, &comstate);
507 if (comstate & TIOCM_CD)
510 syslog(LOG_NOTICE, "carrier now present on %s (sl%d)",
518 /* Signal handler for SIGINT. We just log and exit. */
520 sigint_handler(int signo __unused)
523 syslog(LOG_NOTICE,"SIGINT on %s (sl%d); exiting",dev,unit);
527 /* Signal handler for SIGURG. */
529 sigurg_handler(int signo __unused)
531 int ttydisc = TTYDISC;
533 signal(SIGURG, SIG_IGN);
535 syslog(LOG_NOTICE,"SIGURG on %s (sl%d); hangup",dev,unit);
536 if (ioctl(fd, TIOCSETD, &ttydisc) < 0) {
537 syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
540 cfsetospeed(&tty, B0);
541 if (tcsetattr(fd, TCSANOW, &tty) < 0) {
542 syslog(LOG_ERR, "tcsetattr(TCSANOW): %m");
545 /* Need to go to sighup handler in any case */
546 if (modem_control & CLOCAL)
547 kill (getpid(), SIGHUP);
551 /* Signal handler for SIGTERM. We just log and exit. */
553 sigterm_handler(int signo __unused)
556 syslog(LOG_NOTICE,"SIGTERM on %s (sl%d); exiting",dev,unit);
560 /* Run config_cmd if specified before exiting. */
562 exit_handler(int ret)
567 * First close the slip line in case exit_cmd wants it (like to hang
568 * up a modem or something).
572 if (uucp_lock && locked)
575 /* Remove the PID file */
580 s = (char*) malloc(strlen(config_cmd) + 32);
582 syslog(LOG_ERR, "malloc failed");
585 sprintf (s, "%s %d -1", config_cmd, unit);
586 syslog(LOG_NOTICE, "deconfiguring %s (sl%d):", dev, unit);
587 syslog(LOG_NOTICE, " '%s'", s);
591 /* invoke a shell for exit_cmd. */
593 syslog(LOG_NOTICE,"exiting after running %s", exit_cmd);
599 /* local variables: */
600 /* c-indent-level: 8 */
601 /* c-argdecl-indent: 0 */
602 /* c-label-offset: -8 */
603 /* c-continued-statement-offset: 8 */
604 /* c-brace-offset: 0 */
605 /* comment-column: 32 */