diff options
Diffstat (limited to 'sbin/slattach/slattach.c')
| -rw-r--r-- | sbin/slattach/slattach.c | 601 |
1 files changed, 601 insertions, 0 deletions
diff --git a/sbin/slattach/slattach.c b/sbin/slattach/slattach.c new file mode 100644 index 0000000..9ab7b31 --- /dev/null +++ b/sbin/slattach/slattach.c @@ -0,0 +1,601 @@ +/* + * Copyright (c) 1988 Regents of the University of California. + * All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Rick Adams. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#ifndef lint +static char copyright[] = +"@(#) Copyright (c) 1988 Regents of the University of California.\n\ + All rights reserved.\n"; +#endif /* not lint */ + +#ifndef lint +/*static char sccsid[] = "from: @(#)slattach.c 4.6 (Berkeley) 6/1/90";*/ +static char rcsid[] = "$Id: slattach.c,v 1.21 1996/12/10 17:07:44 wollman Exp $"; +#endif /* not lint */ + +#include <sys/param.h> +#include <sys/types.h> +#include <sys/ioctl.h> +#include <sys/socket.h> +#include <sys/time.h> + +#include <fcntl.h> +#include <netdb.h> +#include <paths.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <strings.h> +#include <syslog.h> +#include <termios.h> +#include <unistd.h> + +#include <netinet/in.h> +#include <net/if.h> +#include <net/slip.h> +#include <net/if_slvar.h> + +#define DEFAULT_BAUD 9600 + +void sighup_handler(); /* SIGHUP handler */ +void sigint_handler(); /* SIGINT handler */ +void sigterm_handler(); /* SIGTERM handler */ +void sigurg_handler(); /* SIGURG handler */ +void exit_handler(int ret); /* run exit_cmd iff specified upon exit. */ +void setup_line(int cflag); /* configure terminal settings */ +void slip_discipline(); /* switch to slip line discipline */ +void configure_network(); /* configure slip interface */ +void acquire_line(); /* get tty device as controling terminal */ + +int fd = -1; +char *dev = (char *)0; /* path name of the tty (e.g. /dev/tty01) */ +char *dvname; /* basename of dev */ +int locked = 0; /* uucp lock active */ +int flow_control = 0; /* non-zero to enable hardware flow control. */ +int modem_control = HUPCL; /* !CLOCAL+HUPCL iff we watch carrier. */ +int comstate; /* TIOCMGET current state of serial driver */ +int redial_on_startup = 0; /* iff non-zero execute redial_cmd on startup */ +speed_t speed = DEFAULT_BAUD; /* baud rate of tty */ +int slflags = 0; /* compression flags */ +int unit = -1; /* slip device unit number */ +int foreground = 0; /* act as demon if zero, else don't fork. */ +int keepal = 0; /* keepalive timeout */ +int outfill = 0; /* outfill timeout */ +int sl_unit = -1; /* unit number */ +int uucp_lock = 0; /* do uucp locking */ +int exiting = 0; /* allready running exit_handler */ + +struct termios tty; /* tty configuration/state */ + +char tty_path[32]; /* path name of the tty (e.g. /dev/tty01) */ +char pidfilename[40]; /* e.g. /var/run/slattach.tty01.pid */ +char *redial_cmd = 0; /* command to exec upon shutdown. */ +char *config_cmd = 0; /* command to exec if slip unit changes. */ +char *exit_cmd = 0; /* command to exec before exiting. */ + +static char usage_str[] = "\ +usage: %s [-acfhlnz] [-e command] [-r command] [-s speed] [-u command] \\\n\ + [-L] [-K timeout] [-O timeout] [-S unit] device\n\ + -a -- autoenable VJ compression\n\ + -c -- enable VJ compression\n\ + -e ECMD -- run ECMD before exiting\n\ + -f -- run in foreground (don't detach from controlling tty)\n\ + -h -- turn on cts/rts style flow control\n\ + -l -- disable modem control (CLOCAL) and ignore carrier detect\n\ + -n -- throw out ICMP packets\n\ + -r RCMD -- run RCMD upon loss of carrier\n\ + -s # -- set baud rate (default 9600)\n\ + -u UCMD -- run 'UCMD <old sl#> <new sl#>' before switch to slip discipline\n\ + -z -- run RCMD upon startup irrespective of carrier\n\ + -L -- do uucp-style device locking\n\ + -K # -- set SLIP \"keep alive\" timeout (default 0)\n\ + -O # -- set SLIP \"out fill\" timeout (default 0)\n\ + -S # -- set SLIP unit number (default is dynamic)\n\ +"; + +int main(int argc, char **argv) +{ + int option; + extern char *optarg; + extern int optind; + + while ((option = getopt(argc, argv, "ace:fhlnr:s:u:zLK:O:S:")) != EOF) { + switch (option) { + case 'a': + slflags |= IFF_LINK2; + slflags &= ~IFF_LINK0; + break; + case 'c': + slflags |= IFF_LINK0; + slflags &= ~IFF_LINK2; + break; + case 'e': + exit_cmd = (char*) strdup (optarg); + break; + case 'f': + foreground = 1; + break; + case 'h': + flow_control |= CRTSCTS; + break; + case 'l': + modem_control = CLOCAL; /* clear HUPCL too */ + break; + case 'n': + slflags |= IFF_LINK1; + break; + case 'r': + redial_cmd = (char*) strdup (optarg); + break; + case 's': + speed = atoi(optarg); + break; + case 'u': + config_cmd = (char*) strdup (optarg); + break; + case 'z': + redial_on_startup = 1; + break; + case 'L': + uucp_lock = 1; + break; + case 'K': + keepal = atoi(optarg); + break; + case 'O': + outfill = atoi(optarg); + break; + case 'S': + sl_unit = atoi(optarg); + break; + default: + fprintf(stderr, "%s: Invalid option -- '%c'\n", + argv[0], option); + case '?': + fprintf(stderr, usage_str, argv[0]); + exit_handler(1); + } + } + + if (optind == argc - 1) + dev = argv[optind]; + + if (optind < (argc - 1)) { + fprintf(stderr, "%s: Too many args, first='%s'\n", + argv[0], argv[optind]); + } + if (optind > (argc - 1)) { + fprintf(stderr, "%s: Not enough args\n", argv[0]); + } + if (dev == (char *)0) { + fprintf(stderr, usage_str, argv[0]); + exit_handler(2); + } + if (strncmp(_PATH_DEV, dev, sizeof(_PATH_DEV) - 1)) { + strcpy(tty_path, _PATH_DEV); + strcat(tty_path, "/"); + strncat(tty_path, dev, 10); + dev = tty_path; + } + dvname = strrchr(dev, '/'); /* always succeeds */ + dvname++; /* trailing tty pathname component */ + sprintf(pidfilename, "%sslattach.%s.pid", _PATH_VARRUN, dvname); + printf("%s\n",pidfilename); + + if (!foreground) + daemon(0,0); /* fork, setsid, chdir /, and close std*. */ + /* daemon() closed stderr, so log errors from here on. */ + openlog("slattach",LOG_CONS|LOG_PID,LOG_DAEMON); + + acquire_line(); /* get tty device as controling terminal */ + setup_line(0); /* configure for slip line discipline */ + slip_discipline(); /* switch to slip line discipline */ + + /* upon INT log a timestamp and exit. */ + if ((int)signal(SIGINT,sigint_handler) < 0) + syslog(LOG_NOTICE,"cannot install SIGINT handler: %m"); + /* upon TERM log a timestamp and exit. */ + if ((int)signal(SIGTERM,sigterm_handler) < 0) + syslog(LOG_NOTICE,"cannot install SIGTERM handler: %m"); + /* upon HUP redial and reconnect. */ + if ((int)signal(SIGHUP,sighup_handler) < 0) + syslog(LOG_NOTICE,"cannot install SIGHUP handler: %m"); + + if (redial_on_startup) + sighup_handler(); + else if (!(modem_control & CLOCAL)) { + if (ioctl(fd, TIOCMGET, &comstate) < 0) + syslog(LOG_NOTICE,"cannot get carrier state: %m"); + if (!(comstate & TIOCM_CD)) { /* check for carrier */ + /* force a redial if no carrier */ + kill (getpid(), SIGHUP); + } else + configure_network(); + } else + configure_network(); /* configure the network if needed. */ + + for (;;) { + sigset_t mask; + sigemptyset(&mask); + sigsuspend(&mask); + } +} + +/* Close all FDs, fork, reopen tty port as 0-2, and make it the + controlling terminal for our process group. */ +void acquire_line() +{ + int ttydisc = TTYDISC; + int oflags; + FILE *pidfile; + + /* reset to tty discipline */ + if (fd >= 0 && ioctl(fd, TIOCSETD, &ttydisc) < 0) { + syslog(LOG_ERR, "ioctl(TIOCSETD): %m"); + exit_handler(1); + } + + (void)close(STDIN_FILENO); /* close FDs before forking. */ + (void)close(STDOUT_FILENO); + (void)close(STDERR_FILENO); + if (fd > 2) + (void)close(fd); + + signal(SIGHUP, SIG_IGN); /* ignore HUP signal when parent dies. */ + if (daemon(0,0)) { /* fork, setsid, chdir /, and close std*. */ + syslog(LOG_ERR, "daemon(0,0): %m"); + exit_handler(1); + } + + while (getppid () != 1) + sleep (1); /* Wait for parent to die. */ + + /* create PID file */ + if((pidfile = fopen(pidfilename, "w"))) { + fprintf(pidfile, "%ld\n", getpid()); + fclose(pidfile); + } + + if ((int)signal(SIGHUP,sighup_handler) < 0) /* Re-enable HUP signal */ + syslog(LOG_NOTICE,"cannot install SIGHUP handler: %m"); + + if (uucp_lock) { + /* unlock not needed here, always re-lock with new pid */ + if (uu_lock(dvname)) { + syslog(LOG_ERR, "can't lock %s", dev); + exit_handler(1); + } + locked = 1; + } + + if ((fd = open(dev, O_RDWR | O_NONBLOCK, 0)) < 0) { + syslog(LOG_ERR, "open(%s) %m", dev); + exit_handler(1); + } + /* Turn off O_NONBLOCK for dumb redialers, if any. */ + if ((oflags = fcntl(fd, F_GETFL)) == -1) { + syslog(LOG_ERR, "fcntl(F_GETFL) failed: %m"); + exit_handler(1); + } + if (fcntl(fd, F_SETFL, oflags & ~O_NONBLOCK) == -1) { + syslog(LOG_ERR, "fcntl(F_SETFL) failed: %m"); + exit_handler(1); + } + (void)dup2(fd, STDIN_FILENO); + (void)dup2(fd, STDOUT_FILENO); + (void)dup2(fd, STDERR_FILENO); + if (fd > 2) + (void)close (fd); + fd = STDIN_FILENO; + + /* acquire the serial line as a controling terminal. */ + if (ioctl(fd, TIOCSCTTY, 0) < 0) { + syslog(LOG_ERR,"ioctl(TIOCSCTTY): %m"); + exit_handler(1); + } + /* Make us the foreground process group associated with the + slip line which is our controlling terminal. */ + if (tcsetpgrp(fd, getpid()) < 0) + syslog(LOG_NOTICE,"tcsetpgrp failed: %m"); +} + +/* Set the tty flags and set DTR. */ +/* Call as setup_line(CLOCAL) to force clocal assertion. */ +void setup_line(int cflag) +{ + tty.c_lflag = tty.c_iflag = tty.c_oflag = 0; + tty.c_cflag = CREAD | CS8 | flow_control | modem_control | cflag; + cfsetispeed(&tty, speed); + cfsetospeed(&tty, speed); + /* set the line speed and flow control */ + if (tcsetattr(fd, TCSAFLUSH, &tty) < 0) { + syslog(LOG_ERR, "tcsetattr(TCSAFLUSH): %m"); + exit_handler(1); + } + /* set data terminal ready */ + if (ioctl(fd, TIOCSDTR) < 0) { + syslog(LOG_ERR, "ioctl(TIOCSDTR): %m"); + exit_handler(1); + } +} + +/* Put the line in slip discipline. */ +void slip_discipline() +{ + struct ifreq ifr; + int slipdisc = SLIPDISC; + int s, tmp_unit = -1; + + /* Switch to slip line discipline. */ + if (ioctl(fd, TIOCSETD, &slipdisc) < 0) { + syslog(LOG_ERR, "ioctl(TIOCSETD): %m"); + exit_handler(1); + } + + if (sl_unit >= 0 && ioctl(fd, SLIOCSUNIT, &sl_unit) < 0) { + syslog(LOG_ERR, "ioctl(SLIOCSUNIT): %m"); + exit_handler(1); + } + + /* find out what unit number we were assigned */ + if (ioctl(fd, SLIOCGUNIT, (caddr_t)&tmp_unit) < 0) { + syslog(LOG_ERR, "ioctl(SLIOCGUNIT): %m"); + exit_handler(1); + } + + if (tmp_unit < 0) { + syslog(LOG_ERR, "bad unit (%d) from ioctl(SLIOCGUNIT)",tmp_unit); + exit_handler(1); + } + + if (keepal > 0) { + signal(SIGURG, sigurg_handler); + if (ioctl(fd, SLIOCSKEEPAL, &keepal) < 0) { + syslog(LOG_ERR, "ioctl(SLIOCSKEEPAL): %m"); + exit_handler(1); + } + } + if (outfill > 0 && ioctl(fd, SLIOCSOUTFILL, &outfill) < 0) { + syslog(LOG_ERR, "ioctl(SLIOCSOUTFILL): %m"); + exit_handler(1); + } + + /* open a socket as the handle to the interface */ + s = socket(AF_INET, SOCK_DGRAM, 0); + if (s < 0) { + syslog(LOG_ERR, "socket: %m"); + exit_handler(1); + } + sprintf(ifr.ifr_name, "sl%d", tmp_unit); + + /* get the flags for the interface */ + if (ioctl(s, SIOCGIFFLAGS, (caddr_t)&ifr) < 0) { + syslog(LOG_ERR, "ioctl (SIOCGIFFLAGS): %m"); + exit_handler(1); + } + + /* Assert any compression or no-icmp flags. */ +#define SLMASK (~(IFF_LINK0 | IFF_LINK1 | IFF_LINK2)) + ifr.ifr_flags &= SLMASK; + ifr.ifr_flags |= slflags; + if (ioctl(s, SIOCSIFFLAGS, (caddr_t)&ifr) < 0) { + syslog(LOG_ERR, "ioctl (SIOCSIFFLAGS): %m"); + exit_handler(1); + } + close(s); +} + +/* configure the interface, eg. by passing the unit number to a script. */ +void configure_network() +{ + int new_unit; + + /* find out what unit number we were assigned */ + if (ioctl(fd, SLIOCGUNIT, (caddr_t)&new_unit) < 0) { + syslog(LOG_ERR, "ioctl(SLIOCGUNIT): %m"); + exit_handler(1); + } + /* iff the unit number changes either invoke config_cmd or punt. */ + if (config_cmd) { + char *s; + s = (char*) malloc(strlen(config_cmd) + 32); + sprintf (s, "%s %d %d", config_cmd, unit, new_unit); + syslog(LOG_NOTICE, "Configuring %s (sl%d):", dev, unit); + syslog(LOG_NOTICE, " '%s'", s); + system(s); + free (s); + unit = new_unit; + } else { + /* don't compare unit numbers if this is the first time to attach. */ + if (unit < 0) + unit = new_unit; + if (new_unit != unit) { + syslog(LOG_ERR, "slip unit changed from sl%d to sl%d, but no -u CMD was specified!"); + exit_handler(1); + } + syslog(LOG_NOTICE,"sl%d connected to %s at %d baud",unit,dev,speed); + } +} + +/* sighup_handler() is invoked when carrier drops, eg. before redial. */ +void sighup_handler() +{ + if(exiting) return; + + if (redial_cmd == NULL) { + syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); exiting", dev, unit); + exit_handler(1); + } +again: + /* invoke a shell for redial_cmd or punt. */ + if (*redial_cmd) { + syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); running '%s'", + dev, unit, redial_cmd); + acquire_line(); /* reopen dead line */ + setup_line(CLOCAL); + if (locked) { + if (uucp_lock) + uu_unlock(dvname); /* for redial */ + locked = 0; + } + if (system(redial_cmd)) + goto again; + if (uucp_lock) { + if (uu_lock(dvname)) { + syslog(LOG_ERR, "can't relock %s after %s, aborting", + dev, redial_cmd); + exit_handler(1); + } + locked = 1; + } + /* Now check again for carrier (dial command is done): */ + if (!(modem_control & CLOCAL)) { + tty.c_cflag &= ~CLOCAL; + if (tcsetattr(fd, TCSAFLUSH, &tty) < 0) { + syslog(LOG_ERR, "tcsetattr(TCSAFLUSH): %m"); + exit_handler(1); + } + ioctl(fd, TIOCMGET, &comstate); + if (!(comstate & TIOCM_CD)) { /* check for carrier */ + /* force a redial if no carrier */ + goto again; + } + } else + setup_line(0); + } else { /* Empty redial command */ + syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); reestablish connection", + dev, unit); + acquire_line(); /* reopen dead line */ + setup_line(0); /* restore ospeed from hangup (B0) */ + /* If modem control, just wait for carrier before attaching. + If no modem control, just fall through immediately. */ + if (!(modem_control & CLOCAL)) { + int carrier = 0; + + syslog(LOG_NOTICE, "Waiting for carrier on %s (sl%d)", + dev, unit); + /* Now wait for carrier before attaching line. */ + /* We must poll since CLOCAL prevents signal. */ + while (! carrier) { + sleep(2); + ioctl(fd, TIOCMGET, &comstate); + if (comstate & TIOCM_CD) + carrier = 1; + } + syslog(LOG_NOTICE, "Carrier now present on %s (sl%d)", + dev, unit); + } + } + slip_discipline(); + configure_network(); +} +/* Signal handler for SIGINT. We just log and exit. */ +void sigint_handler() +{ + if(exiting) return; + syslog(LOG_NOTICE,"SIGINT on %s (sl%d); exiting",dev,unit); + exit_handler(0); +} +/* Signal handler for SIGURG. */ +void sigurg_handler() +{ + int ttydisc = TTYDISC; + + signal(SIGURG, SIG_IGN); + if(exiting) return; + syslog(LOG_NOTICE,"SIGURG on %s (sl%d); hangup",dev,unit); + if (ioctl(fd, TIOCSETD, &ttydisc) < 0) { + syslog(LOG_ERR, "ioctl(TIOCSETD): %m"); + exit_handler(1); + } + cfsetospeed(&tty, B0); + if (tcsetattr(fd, TCSANOW, &tty) < 0) { + syslog(LOG_ERR, "tcsetattr(TCSANOW): %m"); + exit_handler(1); + } + /* Need to go to sighup handler in any case */ + if (modem_control & CLOCAL) + kill (getpid(), SIGHUP); + +} +/* Signal handler for SIGTERM. We just log and exit. */ +void sigterm_handler() +{ + if(exiting) return; + syslog(LOG_NOTICE,"SIGTERM on %s (sl%d); exiting",dev,unit); + exit_handler(0); +} +/* Run config_cmd if specified before exiting. */ +void exit_handler(int ret) +{ + if(exiting) return; + exiting = 1; + /* + * First close the slip line in case exit_cmd wants it (like to hang + * up a modem or something). + */ + if (fd != -1) + close(fd); + if (uucp_lock && locked) + uu_unlock(dvname); + + /* Remove the PID file */ + (void)unlink(pidfilename); + + if (config_cmd) { + char *s; + s = (char*) malloc(strlen(config_cmd) + 32); + sprintf (s, "%s %d -1", config_cmd, unit); + syslog(LOG_NOTICE, "Deconfiguring %s (sl%d):", dev, unit); + syslog(LOG_NOTICE, " '%s'", s); + system(s); + free (s); + } + /* invoke a shell for exit_cmd. */ + if (exit_cmd) { + syslog(LOG_NOTICE,"exiting after running %s", exit_cmd); + system(exit_cmd); + } + exit(ret); +} + +/* local variables: */ +/* c-indent-level: 8 */ +/* c-argdecl-indent: 0 */ +/* c-label-offset: -8 */ +/* c-continued-statement-offset: 8 */ +/* c-brace-offset: 0 */ +/* comment-column: 32 */ +/* end: */ |
