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
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 $
41 #include <sys/types.h>
42 #include <sys/ioctl.h>
43 #include <sys/socket.h>
60 #define DEFAULT_BAUD 9600
62 static void sighup_handler(int); /* SIGHUP handler */
63 static void sigint_handler(int); /* SIGINT handler */
64 static void sigterm_handler(int); /* SIGTERM handler */
65 static void sigurg_handler(int); /* SIGURG handler */
66 static void exit_handler(int); /* run exit_cmd iff specified upon exit. */
67 static void setup_line(int); /* configure terminal settings */
68 static void slip_discipline(void); /* switch to slip line discipline */
69 static void configure_network(void); /* configure slip interface */
70 static void acquire_line(void); /* get tty device as controlling terminal */
71 static void usage(void);
74 char *dev = NULL; /* path name of the tty (e.g. /dev/tty01) */
75 char *dvname; /* basename of dev */
76 int locked = 0; /* uucp lock active */
77 int flow_control = 0; /* non-zero to enable hardware flow control. */
78 int modem_control = HUPCL; /* !CLOCAL+HUPCL iff we watch carrier. */
79 int comstate; /* TIOCMGET current state of serial driver */
80 int redial_on_startup = 0; /* iff non-zero execute redial_cmd on startup */
81 speed_t speed = DEFAULT_BAUD; /* baud rate of tty */
82 int slflags = 0; /* compression flags */
83 int unit = -1; /* slip device unit number */
84 int foreground = 0; /* act as demon if zero, else don't fork. */
85 int keepal = 0; /* keepalive timeout */
86 int outfill = 0; /* outfill timeout */
87 int sl_unit = -1; /* unit number */
88 int uucp_lock = 0; /* do uucp locking */
89 int exiting = 0; /* already running exit_handler */
91 struct termios tty; /* tty configuration/state */
93 char tty_path[32]; /* path name of the tty (e.g. /dev/tty01) */
94 char pidfilename[40]; /* e.g. /var/run/slattach.tty01.pid */
95 char *redial_cmd = NULL; /* command to exec upon shutdown. */
96 char *config_cmd = NULL; /* command to exec if slip unit changes. */
97 char *exit_cmd = NULL; /* command to exec before exiting. */
102 fprintf(stderr, "%s\n%s\n",
103 "usage: slattach [-acfhlnz] [-e command] [-r command] [-s speed] [-u command]",
104 " [-L] [-K timeout] [-O timeout] [-S unit] device");
105 /* do not exit here */
109 main(int argc, char **argv)
113 while ((option = getopt(argc, argv, "ace:fhlnr:s:u:zLK:O:S:")) != -1) {
116 slflags |= IFF_LINK2;
117 slflags &= ~IFF_LINK0;
120 slflags |= IFF_LINK0;
121 slflags &= ~IFF_LINK2;
124 exit_cmd = (char*) strdup (optarg);
130 flow_control |= CRTSCTS;
133 modem_control = CLOCAL; /* clear HUPCL too */
136 slflags |= IFF_LINK1;
139 redial_cmd = (char*) strdup (optarg);
142 speed = atoi(optarg);
145 config_cmd = (char*) strdup (optarg);
148 redial_on_startup = 1;
154 keepal = atoi(optarg);
157 outfill = atoi(optarg);
160 sl_unit = atoi(optarg);
169 if (optind == argc - 1)
172 if (optind < (argc - 1))
173 warnx("too many args, first='%s'", argv[optind]);
174 if (optind > (argc - 1))
175 warnx("not enough args");
180 if (strncmp(_PATH_DEV, dev, sizeof(_PATH_DEV) - 1)) {
181 strcpy(tty_path, _PATH_DEV);
182 strcat(tty_path, "/");
183 strncat(tty_path, dev, 10);
186 dvname = strrchr(dev, '/'); /* always succeeds */
187 dvname++; /* trailing tty pathname component */
188 snprintf(pidfilename, sizeof(pidfilename),
189 "%sslattach.%s.pid", _PATH_VARRUN, dvname);
190 printf("%s\n",pidfilename);
193 daemon(0,0); /* fork, setsid, chdir /, and close std*. */
194 /* daemon() closed stderr, so log errors from here on. */
195 openlog("slattach",LOG_CONS|LOG_PID,LOG_DAEMON);
197 acquire_line(); /* get tty device as controlling terminal */
198 setup_line(0); /* configure for slip line discipline */
199 slip_discipline(); /* switch to slip line discipline */
201 /* upon INT log a timestamp and exit. */
202 if (signal(SIGINT,sigint_handler) == SIG_ERR)
203 syslog(LOG_NOTICE,"cannot install SIGINT handler: %m");
204 /* upon TERM log a timestamp and exit. */
205 if (signal(SIGTERM,sigterm_handler) == SIG_ERR)
206 syslog(LOG_NOTICE,"cannot install SIGTERM handler: %m");
207 /* upon HUP redial and reconnect. */
208 if (signal(SIGHUP,sighup_handler) == SIG_ERR)
209 syslog(LOG_NOTICE,"cannot install SIGHUP handler: %m");
211 if (redial_on_startup)
213 else if (!(modem_control & CLOCAL)) {
214 if (ioctl(fd, TIOCMGET, &comstate) < 0)
215 syslog(LOG_NOTICE,"cannot get carrier state: %m");
216 if (!(comstate & TIOCM_CD)) { /* check for carrier */
217 /* force a redial if no carrier */
218 kill (getpid(), SIGHUP);
222 configure_network(); /* configure the network if needed. */
231 /* Close all FDs, fork, reopen tty port as 0-2, and make it the
232 controlling terminal for our process group. */
236 int ttydisc = TTYDISC;
240 /* reset to tty discipline */
241 if (fd >= 0 && ioctl(fd, TIOCSETD, &ttydisc) < 0) {
242 syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
246 close(STDIN_FILENO); /* close FDs before forking. */
247 close(STDOUT_FILENO);
248 close(STDERR_FILENO);
252 signal(SIGHUP, SIG_IGN); /* ignore HUP signal when parent dies. */
253 if (daemon(0,0)) { /* fork, setsid, chdir /, and close std*. */
254 syslog(LOG_ERR, "daemon(0,0): %m");
258 while (getppid () != 1)
259 sleep (1); /* Wait for parent to die. */
261 /* create PID file */
262 if((pid_file = fopen(pidfilename, "w"))) {
263 fprintf(pid_file, "%ld\n", (long)getpid());
267 if (signal(SIGHUP,sighup_handler) == SIG_ERR) /* Re-enable HUP signal */
268 syslog(LOG_NOTICE,"cannot install SIGHUP handler: %m");
271 /* unlock not needed here, always re-lock with new pid */
273 if ((res = uu_lock(dvname)) != UU_LOCK_OK) {
274 if (res != UU_LOCK_INUSE)
275 syslog(LOG_ERR, "uu_lock: %s", uu_lockerr(res));
276 syslog(LOG_ERR, "can't lock %s", dev);
282 if ((fd = open(dev, O_RDWR | O_NONBLOCK, 0)) < 0) {
283 syslog(LOG_ERR, "open(%s) %m", dev);
286 /* Turn off O_NONBLOCK for dumb redialers, if any. */
287 if ((oflags = fcntl(fd, F_GETFL)) == -1) {
288 syslog(LOG_ERR, "fcntl(F_GETFL) failed: %m");
291 if (fcntl(fd, F_SETFL, oflags & ~O_NONBLOCK) == -1) {
292 syslog(LOG_ERR, "fcntl(F_SETFL) failed: %m");
295 dup2(fd, STDIN_FILENO);
296 dup2(fd, STDOUT_FILENO);
297 dup2(fd, STDERR_FILENO);
302 /* acquire the serial line as a controlling terminal. */
303 if (ioctl(fd, TIOCSCTTY, 0) < 0) {
304 syslog(LOG_ERR,"ioctl(TIOCSCTTY): %m");
307 /* Make us the foreground process group associated with the
308 slip line which is our controlling terminal. */
309 if (tcsetpgrp(fd, getpid()) < 0)
310 syslog(LOG_NOTICE,"tcsetpgrp failed: %m");
313 /* Set the tty flags and set DTR. */
314 /* Call as setup_line(CLOCAL) to force clocal assertion. */
316 setup_line(int cflag)
318 tty.c_lflag = tty.c_iflag = tty.c_oflag = 0;
319 tty.c_cflag = CREAD | CS8 | flow_control | modem_control | cflag;
320 cfsetispeed(&tty, speed);
321 cfsetospeed(&tty, speed);
322 /* set the line speed and flow control */
323 if (tcsetattr(fd, TCSAFLUSH, &tty) < 0) {
324 syslog(LOG_ERR, "tcsetattr(TCSAFLUSH): %m");
327 /* set data terminal ready */
328 if (ioctl(fd, TIOCSDTR) < 0) {
329 syslog(LOG_ERR, "ioctl(TIOCSDTR): %m");
334 /* Put the line in slip discipline. */
336 slip_discipline(void)
339 int slipdisc = SLIPDISC;
340 int s, tmp_unit = -1;
342 /* Switch to slip line discipline. */
343 if (ioctl(fd, TIOCSETD, &slipdisc) < 0) {
344 syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
348 if (sl_unit >= 0 && ioctl(fd, SLIOCSUNIT, &sl_unit) < 0) {
349 syslog(LOG_ERR, "ioctl(SLIOCSUNIT): %m");
353 /* find out what unit number we were assigned */
354 if (ioctl(fd, SLIOCGUNIT, (caddr_t)&tmp_unit) < 0) {
355 syslog(LOG_ERR, "ioctl(SLIOCGUNIT): %m");
360 syslog(LOG_ERR, "bad unit (%d) from ioctl(SLIOCGUNIT)",tmp_unit);
365 signal(SIGURG, sigurg_handler);
366 if (ioctl(fd, SLIOCSKEEPAL, &keepal) < 0) {
367 syslog(LOG_ERR, "ioctl(SLIOCSKEEPAL): %m");
371 if (outfill > 0 && ioctl(fd, SLIOCSOUTFILL, &outfill) < 0) {
372 syslog(LOG_ERR, "ioctl(SLIOCSOUTFILL): %m");
376 /* open a socket as the handle to the interface */
377 s = socket(AF_INET, SOCK_DGRAM, 0);
379 syslog(LOG_ERR, "socket: %m");
382 sprintf(ifr.ifr_name, "sl%d", tmp_unit);
384 /* get the flags for the interface */
385 if (ioctl(s, SIOCGIFFLAGS, (caddr_t)&ifr) < 0) {
386 syslog(LOG_ERR, "ioctl (SIOCGIFFLAGS): %m");
390 /* Assert any compression or no-icmp flags. */
391 #define SLMASK (~(IFF_LINK0 | IFF_LINK1 | IFF_LINK2))
392 ifr.ifr_flags &= SLMASK;
393 ifr.ifr_flags |= slflags;
394 if (ioctl(s, SIOCSIFFLAGS, (caddr_t)&ifr) < 0) {
395 syslog(LOG_ERR, "ioctl (SIOCSIFFLAGS): %m");
401 /* configure the interface, e.g. by passing the unit number to a script. */
403 configure_network(void)
407 /* find out what unit number we were assigned */
408 if (ioctl(fd, SLIOCGUNIT, (caddr_t)&new_unit) < 0) {
409 syslog(LOG_ERR, "ioctl(SLIOCGUNIT): %m");
412 /* iff the unit number changes either invoke config_cmd or punt. */
415 s = (char*) malloc(strlen(config_cmd) + 32);
417 syslog(LOG_ERR, "malloc failed");
420 sprintf (s, "%s %d %d", config_cmd, unit, new_unit);
421 syslog(LOG_NOTICE, "configuring %s (sl%d):", dev, unit);
422 syslog(LOG_NOTICE, " '%s'", s);
427 /* don't compare unit numbers if this is the first time to attach. */
430 if (new_unit != unit) {
432 "slip unit changed from sl%d to sl%d, but no -u CMD was specified!",
436 syslog(LOG_NOTICE,"sl%d connected to %s at %d baud",unit,dev,speed);
440 /* sighup_handler() is invoked when carrier drops, eg. before redial. */
442 sighup_handler(int signo __unused)
446 if (redial_cmd == NULL) {
447 syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); exiting", dev, unit);
451 /* invoke a shell for redial_cmd or punt. */
452 if (*redial_cmd) { /* Non-empty redial command */
453 syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); running '%s'",
454 dev, unit, redial_cmd);
455 acquire_line(); /* reopen dead line */
459 uu_unlock(dvname); /* for redial */
462 if (system(redial_cmd))
466 if ((res = uu_lock(dvname)) != UU_LOCK_OK) {
467 if (res != UU_LOCK_INUSE)
468 syslog(LOG_ERR, "uu_lock: %s", uu_lockerr(res));
469 syslog(LOG_ERR, "can't relock %s after %s, aborting",
475 /* Now check again for carrier (dial command is done): */
476 if (!(modem_control & CLOCAL)) {
477 tty.c_cflag &= ~CLOCAL;
478 if (tcsetattr(fd, TCSAFLUSH, &tty) < 0) {
479 syslog(LOG_ERR, "tcsetattr(TCSAFLUSH): %m");
482 ioctl(fd, TIOCMGET, &comstate);
483 if (!(comstate & TIOCM_CD)) { /* check for carrier */
484 /* force a redial if no carrier */
489 } else { /* Empty redial command */
490 syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); reestablish connection",
492 acquire_line(); /* reopen dead line */
493 setup_line(0); /* restore ospeed from hangup (B0) */
494 /* If modem control, just wait for carrier before attaching.
495 If no modem control, just fall through immediately. */
496 if (!(modem_control & CLOCAL)) {
499 syslog(LOG_NOTICE, "waiting for carrier on %s (sl%d)",
501 /* Now wait for carrier before attaching line. */
502 /* We must poll since CLOCAL prevents signal. */
505 ioctl(fd, TIOCMGET, &comstate);
506 if (comstate & TIOCM_CD)
509 syslog(LOG_NOTICE, "carrier now present on %s (sl%d)",
517 /* Signal handler for SIGINT. We just log and exit. */
519 sigint_handler(int signo __unused)
522 syslog(LOG_NOTICE,"SIGINT on %s (sl%d); exiting",dev,unit);
526 /* Signal handler for SIGURG. */
528 sigurg_handler(int signo __unused)
530 int ttydisc = TTYDISC;
532 signal(SIGURG, SIG_IGN);
534 syslog(LOG_NOTICE,"SIGURG on %s (sl%d); hangup",dev,unit);
535 if (ioctl(fd, TIOCSETD, &ttydisc) < 0) {
536 syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
539 cfsetospeed(&tty, B0);
540 if (tcsetattr(fd, TCSANOW, &tty) < 0) {
541 syslog(LOG_ERR, "tcsetattr(TCSANOW): %m");
544 /* Need to go to sighup handler in any case */
545 if (modem_control & CLOCAL)
546 kill (getpid(), SIGHUP);
550 /* Signal handler for SIGTERM. We just log and exit. */
552 sigterm_handler(int signo __unused)
555 syslog(LOG_NOTICE,"SIGTERM on %s (sl%d); exiting",dev,unit);
559 /* Run config_cmd if specified before exiting. */
561 exit_handler(int ret)
566 * First close the slip line in case exit_cmd wants it (like to hang
567 * up a modem or something).
571 if (uucp_lock && locked)
574 /* Remove the PID file */
579 s = (char*) malloc(strlen(config_cmd) + 32);
581 syslog(LOG_ERR, "malloc failed");
584 sprintf (s, "%s %d -1", config_cmd, unit);
585 syslog(LOG_NOTICE, "deconfiguring %s (sl%d):", dev, unit);
586 syslog(LOG_NOTICE, " '%s'", s);
590 /* invoke a shell for exit_cmd. */
592 syslog(LOG_NOTICE,"exiting after running %s", exit_cmd);
598 /* local variables: */
599 /* c-indent-level: 8 */
600 /* c-argdecl-indent: 0 */
601 /* c-label-offset: -8 */
602 /* c-continued-statement-offset: 8 */
603 /* c-brace-offset: 0 */
604 /* comment-column: 32 */