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. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * @(#) Copyright (c) 1988 Regents of the University of California. All rights reserved.
33 * @(#)slattach.c 4.6 (Berkeley) 6/1/90
34 * $FreeBSD: src/sbin/slattach/slattach.c,v 1.36 1999/08/28 00:14:25 peter Exp $
37 #include <sys/types.h>
38 #include <sys/ioctl.h>
39 #include <sys/socket.h>
56 #define DEFAULT_BAUD 9600
58 static void sighup_handler(int); /* SIGHUP handler */
59 static void sigint_handler(int); /* SIGINT handler */
60 static void sigterm_handler(int); /* SIGTERM handler */
61 static void sigurg_handler(int); /* SIGURG handler */
62 static void exit_handler(int); /* run exit_cmd iff specified upon exit. */
63 static void setup_line(int); /* configure terminal settings */
64 static void slip_discipline(void); /* switch to slip line discipline */
65 static void configure_network(void); /* configure slip interface */
66 static void acquire_line(void); /* get tty device as controlling terminal */
67 static void usage(void);
70 char *dev = NULL; /* path name of the tty (e.g. /dev/tty01) */
71 char *dvname; /* basename of dev */
72 int locked = 0; /* uucp lock active */
73 int flow_control = 0; /* non-zero to enable hardware flow control. */
74 int modem_control = HUPCL; /* !CLOCAL+HUPCL iff we watch carrier. */
75 int comstate; /* TIOCMGET current state of serial driver */
76 int redial_on_startup = 0; /* iff non-zero execute redial_cmd on startup */
77 speed_t speed = DEFAULT_BAUD; /* baud rate of tty */
78 int slflags = 0; /* compression flags */
79 int unit = -1; /* slip device unit number */
80 int foreground = 0; /* act as demon if zero, else don't fork. */
81 int keepal = 0; /* keepalive timeout */
82 int outfill = 0; /* outfill timeout */
83 int sl_unit = -1; /* unit number */
84 int uucp_lock = 0; /* do uucp locking */
85 int exiting = 0; /* already running exit_handler */
87 struct termios tty; /* tty configuration/state */
89 char tty_path[32]; /* path name of the tty (e.g. /dev/tty01) */
90 char pidfilename[40]; /* e.g. /var/run/slattach.tty01.pid */
91 char *redial_cmd = NULL; /* command to exec upon shutdown. */
92 char *config_cmd = NULL; /* command to exec if slip unit changes. */
93 char *exit_cmd = NULL; /* command to exec before exiting. */
98 fprintf(stderr, "%s\n%s\n",
99 "usage: slattach [-acfhlnz] [-e command] [-r command] [-s speed] [-u command]",
100 " [-L] [-K timeout] [-O timeout] [-S unit] device");
101 /* do not exit here */
105 main(int argc, char **argv)
109 while ((option = getopt(argc, argv, "ace:fhlnr:s:u:zLK:O:S:")) != -1) {
112 slflags |= IFF_LINK2;
113 slflags &= ~IFF_LINK0;
116 slflags |= IFF_LINK0;
117 slflags &= ~IFF_LINK2;
120 exit_cmd = (char*) strdup (optarg);
126 flow_control |= CRTSCTS;
129 modem_control = CLOCAL; /* clear HUPCL too */
132 slflags |= IFF_LINK1;
135 redial_cmd = (char*) strdup (optarg);
138 speed = atoi(optarg);
141 config_cmd = (char*) strdup (optarg);
144 redial_on_startup = 1;
150 keepal = atoi(optarg);
153 outfill = atoi(optarg);
156 sl_unit = atoi(optarg);
165 if (optind == argc - 1)
168 if (optind < (argc - 1))
169 warnx("too many args, first='%s'", argv[optind]);
170 if (optind > (argc - 1))
171 warnx("not enough args");
176 if (strncmp(_PATH_DEV, dev, sizeof(_PATH_DEV) - 1)) {
177 strcpy(tty_path, _PATH_DEV);
178 strcat(tty_path, "/");
179 strncat(tty_path, dev, 10);
182 dvname = strrchr(dev, '/'); /* always succeeds */
183 dvname++; /* trailing tty pathname component */
184 snprintf(pidfilename, sizeof(pidfilename),
185 "%sslattach.%s.pid", _PATH_VARRUN, dvname);
186 printf("%s\n",pidfilename);
189 daemon(0,0); /* fork, setsid, chdir /, and close std*. */
190 /* daemon() closed stderr, so log errors from here on. */
191 openlog("slattach",LOG_CONS|LOG_PID,LOG_DAEMON);
193 acquire_line(); /* get tty device as controlling terminal */
194 setup_line(0); /* configure for slip line discipline */
195 slip_discipline(); /* switch to slip line discipline */
197 /* upon INT log a timestamp and exit. */
198 if (signal(SIGINT,sigint_handler) == SIG_ERR)
199 syslog(LOG_NOTICE,"cannot install SIGINT handler: %m");
200 /* upon TERM log a timestamp and exit. */
201 if (signal(SIGTERM,sigterm_handler) == SIG_ERR)
202 syslog(LOG_NOTICE,"cannot install SIGTERM handler: %m");
203 /* upon HUP redial and reconnect. */
204 if (signal(SIGHUP,sighup_handler) == SIG_ERR)
205 syslog(LOG_NOTICE,"cannot install SIGHUP handler: %m");
207 if (redial_on_startup)
209 else if (!(modem_control & CLOCAL)) {
210 if (ioctl(fd, TIOCMGET, &comstate) < 0)
211 syslog(LOG_NOTICE,"cannot get carrier state: %m");
212 if (!(comstate & TIOCM_CD)) { /* check for carrier */
213 /* force a redial if no carrier */
214 kill (getpid(), SIGHUP);
218 configure_network(); /* configure the network if needed. */
227 /* Close all FDs, fork, reopen tty port as 0-2, and make it the
228 controlling terminal for our process group. */
232 int ttydisc = TTYDISC;
236 /* reset to tty discipline */
237 if (fd >= 0 && ioctl(fd, TIOCSETD, &ttydisc) < 0) {
238 syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
242 close(STDIN_FILENO); /* close FDs before forking. */
243 close(STDOUT_FILENO);
244 close(STDERR_FILENO);
248 signal(SIGHUP, SIG_IGN); /* ignore HUP signal when parent dies. */
249 if (daemon(0,0)) { /* fork, setsid, chdir /, and close std*. */
250 syslog(LOG_ERR, "daemon(0,0): %m");
254 while (getppid () != 1)
255 sleep (1); /* Wait for parent to die. */
257 /* create PID file */
258 if((pid_file = fopen(pidfilename, "w"))) {
259 fprintf(pid_file, "%ld\n", (long)getpid());
263 if (signal(SIGHUP,sighup_handler) == SIG_ERR) /* Re-enable HUP signal */
264 syslog(LOG_NOTICE,"cannot install SIGHUP handler: %m");
267 /* unlock not needed here, always re-lock with new pid */
269 if ((res = uu_lock(dvname)) != UU_LOCK_OK) {
270 if (res != UU_LOCK_INUSE)
271 syslog(LOG_ERR, "uu_lock: %s", uu_lockerr(res));
272 syslog(LOG_ERR, "can't lock %s", dev);
278 if ((fd = open(dev, O_RDWR | O_NONBLOCK, 0)) < 0) {
279 syslog(LOG_ERR, "open(%s) %m", dev);
282 /* Turn off O_NONBLOCK for dumb redialers, if any. */
283 if ((oflags = fcntl(fd, F_GETFL)) == -1) {
284 syslog(LOG_ERR, "fcntl(F_GETFL) failed: %m");
287 if (fcntl(fd, F_SETFL, oflags & ~O_NONBLOCK) == -1) {
288 syslog(LOG_ERR, "fcntl(F_SETFL) failed: %m");
291 dup2(fd, STDIN_FILENO);
292 dup2(fd, STDOUT_FILENO);
293 dup2(fd, STDERR_FILENO);
298 /* acquire the serial line as a controlling terminal. */
299 if (ioctl(fd, TIOCSCTTY, 0) < 0) {
300 syslog(LOG_ERR,"ioctl(TIOCSCTTY): %m");
303 /* Make us the foreground process group associated with the
304 slip line which is our controlling terminal. */
305 if (tcsetpgrp(fd, getpid()) < 0)
306 syslog(LOG_NOTICE,"tcsetpgrp failed: %m");
309 /* Set the tty flags and set DTR. */
310 /* Call as setup_line(CLOCAL) to force clocal assertion. */
312 setup_line(int cflag)
314 tty.c_lflag = tty.c_iflag = tty.c_oflag = 0;
315 tty.c_cflag = CREAD | CS8 | flow_control | modem_control | cflag;
316 cfsetispeed(&tty, speed);
317 cfsetospeed(&tty, speed);
318 /* set the line speed and flow control */
319 if (tcsetattr(fd, TCSAFLUSH, &tty) < 0) {
320 syslog(LOG_ERR, "tcsetattr(TCSAFLUSH): %m");
323 /* set data terminal ready */
324 if (ioctl(fd, TIOCSDTR) < 0) {
325 syslog(LOG_ERR, "ioctl(TIOCSDTR): %m");
330 /* Put the line in slip discipline. */
332 slip_discipline(void)
335 int slipdisc = SLIPDISC;
336 int s, tmp_unit = -1;
338 /* Switch to slip line discipline. */
339 if (ioctl(fd, TIOCSETD, &slipdisc) < 0) {
340 syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
344 if (sl_unit >= 0 && ioctl(fd, SLIOCSUNIT, &sl_unit) < 0) {
345 syslog(LOG_ERR, "ioctl(SLIOCSUNIT): %m");
349 /* find out what unit number we were assigned */
350 if (ioctl(fd, SLIOCGUNIT, (caddr_t)&tmp_unit) < 0) {
351 syslog(LOG_ERR, "ioctl(SLIOCGUNIT): %m");
356 syslog(LOG_ERR, "bad unit (%d) from ioctl(SLIOCGUNIT)",tmp_unit);
361 signal(SIGURG, sigurg_handler);
362 if (ioctl(fd, SLIOCSKEEPAL, &keepal) < 0) {
363 syslog(LOG_ERR, "ioctl(SLIOCSKEEPAL): %m");
367 if (outfill > 0 && ioctl(fd, SLIOCSOUTFILL, &outfill) < 0) {
368 syslog(LOG_ERR, "ioctl(SLIOCSOUTFILL): %m");
372 /* open a socket as the handle to the interface */
373 s = socket(AF_INET, SOCK_DGRAM, 0);
375 syslog(LOG_ERR, "socket: %m");
378 sprintf(ifr.ifr_name, "sl%d", tmp_unit);
380 /* get the flags for the interface */
381 if (ioctl(s, SIOCGIFFLAGS, (caddr_t)&ifr) < 0) {
382 syslog(LOG_ERR, "ioctl (SIOCGIFFLAGS): %m");
386 /* Assert any compression or no-icmp flags. */
387 #define SLMASK (~(IFF_LINK0 | IFF_LINK1 | IFF_LINK2))
388 ifr.ifr_flags &= SLMASK;
389 ifr.ifr_flags |= slflags;
390 if (ioctl(s, SIOCSIFFLAGS, (caddr_t)&ifr) < 0) {
391 syslog(LOG_ERR, "ioctl (SIOCSIFFLAGS): %m");
397 /* configure the interface, e.g. by passing the unit number to a script. */
399 configure_network(void)
403 /* find out what unit number we were assigned */
404 if (ioctl(fd, SLIOCGUNIT, (caddr_t)&new_unit) < 0) {
405 syslog(LOG_ERR, "ioctl(SLIOCGUNIT): %m");
408 /* iff the unit number changes either invoke config_cmd or punt. */
411 s = (char*) malloc(strlen(config_cmd) + 32);
413 syslog(LOG_ERR, "malloc failed");
416 sprintf (s, "%s %d %d", config_cmd, unit, new_unit);
417 syslog(LOG_NOTICE, "configuring %s (sl%d):", dev, unit);
418 syslog(LOG_NOTICE, " '%s'", s);
423 /* don't compare unit numbers if this is the first time to attach. */
426 if (new_unit != unit) {
428 "slip unit changed from sl%d to sl%d, but no -u CMD was specified!",
432 syslog(LOG_NOTICE,"sl%d connected to %s at %d baud",unit,dev,speed);
436 /* sighup_handler() is invoked when carrier drops, eg. before redial. */
438 sighup_handler(int signo __unused)
442 if (redial_cmd == NULL) {
443 syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); exiting", dev, unit);
447 /* invoke a shell for redial_cmd or punt. */
448 if (*redial_cmd) { /* Non-empty redial command */
449 syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); running '%s'",
450 dev, unit, redial_cmd);
451 acquire_line(); /* reopen dead line */
455 uu_unlock(dvname); /* for redial */
458 if (system(redial_cmd))
462 if ((res = uu_lock(dvname)) != UU_LOCK_OK) {
463 if (res != UU_LOCK_INUSE)
464 syslog(LOG_ERR, "uu_lock: %s", uu_lockerr(res));
465 syslog(LOG_ERR, "can't relock %s after %s, aborting",
471 /* Now check again for carrier (dial command is done): */
472 if (!(modem_control & CLOCAL)) {
473 tty.c_cflag &= ~CLOCAL;
474 if (tcsetattr(fd, TCSAFLUSH, &tty) < 0) {
475 syslog(LOG_ERR, "tcsetattr(TCSAFLUSH): %m");
478 ioctl(fd, TIOCMGET, &comstate);
479 if (!(comstate & TIOCM_CD)) { /* check for carrier */
480 /* force a redial if no carrier */
485 } else { /* Empty redial command */
486 syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); reestablish connection",
488 acquire_line(); /* reopen dead line */
489 setup_line(0); /* restore ospeed from hangup (B0) */
490 /* If modem control, just wait for carrier before attaching.
491 If no modem control, just fall through immediately. */
492 if (!(modem_control & CLOCAL)) {
495 syslog(LOG_NOTICE, "waiting for carrier on %s (sl%d)",
497 /* Now wait for carrier before attaching line. */
498 /* We must poll since CLOCAL prevents signal. */
501 ioctl(fd, TIOCMGET, &comstate);
502 if (comstate & TIOCM_CD)
505 syslog(LOG_NOTICE, "carrier now present on %s (sl%d)",
513 /* Signal handler for SIGINT. We just log and exit. */
515 sigint_handler(int signo __unused)
518 syslog(LOG_NOTICE,"SIGINT on %s (sl%d); exiting",dev,unit);
522 /* Signal handler for SIGURG. */
524 sigurg_handler(int signo __unused)
526 int ttydisc = TTYDISC;
528 signal(SIGURG, SIG_IGN);
530 syslog(LOG_NOTICE,"SIGURG on %s (sl%d); hangup",dev,unit);
531 if (ioctl(fd, TIOCSETD, &ttydisc) < 0) {
532 syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
535 cfsetospeed(&tty, B0);
536 if (tcsetattr(fd, TCSANOW, &tty) < 0) {
537 syslog(LOG_ERR, "tcsetattr(TCSANOW): %m");
540 /* Need to go to sighup handler in any case */
541 if (modem_control & CLOCAL)
542 kill (getpid(), SIGHUP);
546 /* Signal handler for SIGTERM. We just log and exit. */
548 sigterm_handler(int signo __unused)
551 syslog(LOG_NOTICE,"SIGTERM on %s (sl%d); exiting",dev,unit);
555 /* Run config_cmd if specified before exiting. */
557 exit_handler(int ret)
562 * First close the slip line in case exit_cmd wants it (like to hang
563 * up a modem or something).
567 if (uucp_lock && locked)
570 /* Remove the PID file */
575 s = (char*) malloc(strlen(config_cmd) + 32);
577 syslog(LOG_ERR, "malloc failed");
580 sprintf (s, "%s %d -1", config_cmd, unit);
581 syslog(LOG_NOTICE, "deconfiguring %s (sl%d):", dev, unit);
582 syslog(LOG_NOTICE, " '%s'", s);
586 /* invoke a shell for exit_cmd. */
588 syslog(LOG_NOTICE,"exiting after running %s", exit_cmd);
594 /* local variables: */
595 /* c-indent-level: 8 */
596 /* c-argdecl-indent: 0 */
597 /* c-label-offset: -8 */
598 /* c-continued-statement-offset: 8 */
599 /* c-brace-offset: 0 */
600 /* comment-column: 32 */