From 97605525f56dbfdbdc1985d067e7d4da8230a948 Mon Sep 17 00:00:00 2001 From: Rich Murphey Date: Tue, 23 Aug 1994 08:28:32 +0000 Subject: [PATCH] Once again, slattach sources ported from 1.1.5 with fixes. Reviewed by: davidg, bde Submitted by: rich --- sbin/slattach/Makefile | 5 +- sbin/slattach/slattach.8 | 6 +- sbin/slattach/slattach.c | 293 ++++++++++++++++----------------------- 3 files changed, 127 insertions(+), 177 deletions(-) diff --git a/sbin/slattach/Makefile b/sbin/slattach/Makefile index 285c4940df0e..bdc48a9f57dc 100644 --- a/sbin/slattach/Makefile +++ b/sbin/slattach/Makefile @@ -1,5 +1,6 @@ -# from: @(#)Makefile 5.4 (Berkeley) 5/11/90 -# $Id: Makefile,v 1.6 1993/10/13 07:16:38 rgrimes Exp $ +# @(#)Makefile 5.4 (Berkeley) 5/11/90 +# +# $Header: /a/cvs/386BSD/src/sbin/slattach/Makefile,v 1.5 1993/08/29 18:11:14 rgrimes Exp $ PROG= slattach MAN8= slattach.8 diff --git a/sbin/slattach/slattach.8 b/sbin/slattach/slattach.8 index e45ba3c2cbd9..f346824e3da8 100644 --- a/sbin/slattach/slattach.8 +++ b/sbin/slattach/slattach.8 @@ -29,9 +29,9 @@ .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.\" from: @(#)slattach.8 6.4 (Berkeley) 3/16/91 +.\" @(#)slattach.8 6.4 (Berkeley) 3/16/91 .\" -.\" $Id: slattach.8,v 1.7 1993/10/13 07:16:39 rgrimes Exp $ +.\" $Header: /a/cvs/386BSD/src/sbin/slattach/slattach.8,v 1.6 1993/09/15 21:18:07 jkh Exp $ .\" .Dd April 4, 1993 .Dt SLATTACH 8 @@ -39,7 +39,7 @@ .Sh NAME .Nm slattach .Nd attach serial lines as network interfaces -.Sh SYOPNSIS +.Sh SYNOPSIS .Nm Slattach .Op \-a .Op \-c diff --git a/sbin/slattach/slattach.c b/sbin/slattach/slattach.c index 8d429f06ef3a..89871239b982 100644 --- a/sbin/slattach/slattach.c +++ b/sbin/slattach/slattach.c @@ -34,63 +34,8 @@ * SUCH DAMAGE. */ -/* - * Hacks to support "-a|c|n" flags on the command line which enable VJ - * header compresion and disable ICMP. - * If this is good all rights go to B & L Jolitz, otherwise send your - * comments to Reagan (/dev/null). - * - * nerd@percival.rain.com (Michael Galassi) 92.09.03 - * - * Hacked to change from sgtty to POSIX termio style serial line control - * and added flag to enable cts/rts style flow control. - * - * blymn@awadi.com.au (Brett Lymn) 93.04.04 - * - * Put slattach in it's own process group so it can't be killed - * accidentally. Close the connection on SIGHUP and SIGINT. Write a - * syslog entry upon opening and closing the connection. Rich Murphey - * and Brad Huntting. - * - * Add '-r command' option: runs 'command' upon recieving SIGHUP - * resulting from loss of carrier. Log any errors after forking. - * Rich 8/13/93 - * - * This version of slattach includes many changes by David Greenman, Brian - * Smith, Chris Bradley, and me (Michael Galassi). None of them are - * represented as functional anywhere outside of RAINet though they do work - * for us. Documentation is limited to the usage message for now. If you - * make improovments please pass them back. - * - * Added '-u UCMD' which runs 'UCMD ' whenever the slip - * unit number changes where and are the old and new unit - * numbers, respectively. Also added the '-z' option which forces - * invocation of the redial command (-r CMD) upon startup regardless - * of whether the com driver claims (sometimes mistakenly) that - * carrier is present. Also added '-e ECMD' which runs ECMD before - * exiting. - * - * marc@escargot.rain.com (Marc Frajola) 93/09/10 - * - * Minor fixes to allow passive SLIP links to work (connections with - * modem control that do not have an associated dial command). Added - * code to re-check for carrier after dial command has been executed. - * Added SIGTERM handler to properly handle normal kill signals. Fixed - * bug in logic that caused message about no -u command to be logged - * even when -u was specified and the sl number changes. Tried to get - * rid of redundant syslog()'s to minimize console log output. Improved - * logging of improper command line options or number of command - * arguments. Removed spurious newline characters from syslog() calls. - * - * gjung@gjbsd.franken.de - * - * sighup_handler changed to set CLOCAL before running redial_cmd. - * added flag exiting, so exit_handler is not run twice. - * - */ - #ifndef lint -char copyright[] = +static char copyright[] = "@(#) Copyright (c) 1988 Regents of the University of California.\n\ All rights reserved.\n"; #endif /* not lint */ @@ -106,6 +51,7 @@ static char rcsid[] = "$Id"; #include #include #include +#include #include #include #include @@ -117,42 +63,35 @@ static char rcsid[] = "$Id"; #include #include -extern int errno; -extern char *sys_errlist[]; - #define DEFAULT_BAUD 9600 void sighup_handler(); /* SIGHUP handler */ void sigint_handler(); /* SIGINT handler */ void sigterm_handler(); /* SIGTERM handler */ void exit_handler(int ret); /* run exit_cmd iff specified upon exit. */ -void setup_line(); /* configure slip line */ -void attach_line(); /* switch to slip line discipline */ +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; -int slipdisc = SLIPDISC; -int ttydisc = TTYDISC; +char *dev = (char *)0; /* path name of the tty (e.g. /dev/tty01) */ int flow_control = 0; /* non-zero to enable hardware flow control. */ int modem_control = 0; /* non-zero 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 */ -int speed = DEFAULT_BAUD; +int speed = DEFAULT_BAUD; /* baud rate of tty */ int slflags = 0; /* compression flags */ int unit = -1; /* slip device unit number */ -int foreground = 0; +int foreground = 0; /* act as demon if zero, else don't fork. */ int exiting = 0; /* allready running exit_handler */ -FILE *console; -struct termios tty; -struct termios tty_orig; /* For saving original tty state */ +struct termios tty; /* tty configuration/state */ -char devname[32]; -char hostname[MAXHOSTNAMELEN]; +char tty_path[32]; /* path name of the tty (e.g. /dev/tty01) */ 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. */ -char string[100]; static char usage_str[] = "\ usage: %s [-acfhlnz] [-e command] [-r command] [-s speed] [-u command] device\n\ @@ -171,19 +110,18 @@ usage: %s [-acfhlnz] [-e command] [-r command] [-s speed] [-u command] device\n\ int main(int argc, char **argv) { int option; - char name[32]; extern char *optarg; extern int optind; while ((option = getopt(argc, argv, "ace:fhlnr:s:u:z")) != EOF) { switch (option) { case 'a': - slflags |= SC_AUTOCOMP; - slflags &= ~SC_COMPRESS; + slflags |= IFF_LINK2; + slflags &= ~IFF_LINK0; break; case 'c': - slflags |= SC_COMPRESS; - slflags &= ~SC_AUTOCOMP; + slflags |= IFF_LINK0; + slflags &= ~IFF_LINK2; break; case 'e': exit_cmd = (char*) strdup (optarg); @@ -198,7 +136,7 @@ int main(int argc, char **argv) modem_control |= CLOCAL; break; case 'n': - slflags |= SC_NOICMP; + slflags |= IFF_LINK1; break; case 'r': redial_cmd = (char*) strdup (optarg); @@ -236,30 +174,21 @@ int main(int argc, char **argv) exit_handler(2); } if (strncmp(_PATH_DEV, dev, sizeof(_PATH_DEV) - 1)) { - strcpy(devname, _PATH_DEV); - strcat(devname, "/"); - strncat(devname, dev, 10); - dev = devname; + strcpy(tty_path, _PATH_DEV); + strcat(tty_path, "/"); + strncat(tty_path, dev, 10); + dev = tty_path; } 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); - /* Note: daemon() closes stderr, so log errors from here on. */ - (void)sprintf(name,"slattach[%d]", getpid()); - openlog(name,LOG_CONS,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 */ - if ((fd = open(dev, O_RDWR | O_NONBLOCK)) < 0) { - syslog(LOG_ERR, "open(%s): %m", dev); - exit_handler(1); - } - /* acquire the serial line as a controling terminal. */ - if (ioctl(fd, TIOCSCTTY, 0) < 0) - syslog(LOG_NOTICE,"ioctl(TIOCSCTTY) failed: %s: %m"); - /* 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: %s: %m"); /* upon INT log a timestamp and exit. */ if ((int)signal(SIGINT,sigint_handler) < 0) syslog(LOG_NOTICE,"cannot install SIGINT handler: %s: %m"); @@ -269,61 +198,108 @@ int main(int argc, char **argv) /* upon HUP redial and reconnect. */ if ((int)signal(SIGHUP,sighup_handler) < 0) syslog(LOG_NOTICE,"cannot install SIGHUP handler: %s: %m"); - /* Keep track of our original terminal values for redialing */ - if (tcgetattr(fd, &tty_orig) < 0) { - syslog(LOG_ERR, "tcgetattr: %m"); - exit_handler(1); - } - - - setup_line(); if (redial_on_startup) sighup_handler(); - else - attach_line(); - if (!(modem_control & CLOCAL)) { + else if (!(modem_control & CLOCAL)) { ioctl(fd, TIOCMGET, &comstate); if (!(comstate & TIOCM_CD)) { /* check for carrier */ /* force a redial if no carrier */ kill (getpid(), SIGHUP); } } + else + configure_network(); /* configure the network if needed. */ + for (;;) { - sigset_t mask = 0; + sigset_t mask; + sigemptyset(&mask); sigsuspend(&mask); } } -void setup_line() +/* 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 pgrp; + + ioctl(fd, TIOCSETD, &ttydisc); /* reset to tty discipline */ + + (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. */ + daemon(0,0); /* fork, setsid, chdir /, and close std*. */ + + while (getppid () != 1) + sleep (1); /* Wait for parent to die. */ + + if ((int)signal(SIGHUP,sighup_handler) < 0) /* Re-enable HUP signal */ + syslog(LOG_NOTICE,"cannot install SIGHUP handler: %s: %m"); + + if ((fd = open(dev, O_RDWR | O_NONBLOCK, 0)) < 0) { + syslog(LOG_ERR, "open(%s) fd=%d: %m", dev, fd); + 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_NOTICE,"ioctl(TIOCSCTTY) failed: %s: %m"); + /* 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: %s: %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; + tty.c_cflag = CREAD | CS8 | flow_control | modem_control | cflag; tty.c_ispeed = tty.c_ospeed = speed; /* set the line speed and flow control */ if (tcsetattr(fd, TCSAFLUSH, &tty) < 0) { - syslog(LOG_ERR, "tcsetattr(TCSAFLUSH): %m"); + 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); - } - /* Switch to slip line discipline. */ - if (ioctl(fd, TIOCSETD, &slipdisc) < 0) { - syslog(LOG_ERR, "ioctl(TIOCSETD): %m"); - exit_handler(1); - } - /* Assert any compression or no-icmp flags. */ - if (ioctl(fd, SLIOCSFLAGS, &slflags) < 0) { - syslog(LOG_ERR, "ioctl(SLIOCSFLAGS): %m"); + syslog(LOG_ERR, "ioctl(TIOCSDTR): %m"); exit_handler(1); } } -/* switch to slip line discipline and configure the network. */ -void attach_line() +/* Put the line in slip discipline. */ +void slip_discipline() +{ + int slipdisc = SLIPDISC; + + /* Switch to slip line discipline. */ + if (ioctl(fd, TIOCSETD, &slipdisc) < 0) { + syslog(LOG_ERR, "ioctl(TIOCSETD): %m"); + exit_handler(1); + } + /* Assert any compression or no-icmp flags. */ + if (ioctl(fd, SIOCSIFFLAGS, &slflags) < 0) { + syslog(LOG_ERR, "ioctl(SIOCSIFFLAGS): %m"); + exit_handler(1); + } +} + +/* configure the interface, eg. by passing the unit number to a script. */ +void configure_network() { int new_unit; @@ -354,27 +330,17 @@ void attach_line() } } -/* Signal handler for SIGHUP when carrier is dropped. */ +/* signup_handler() is invoked when carrier drops, eg. before redial. */ void sighup_handler() { if(exiting) return; again: - /* reset discipline */ - if (ioctl(fd, TIOCSETD, &ttydisc) < 0) { - syslog(LOG_ERR, "ioctl(TIOCSETD): %m"); - exit_handler(1); - } /* invoke a shell for redial_cmd or punt. */ if (redial_cmd) { + acquire_line(); + setup_line(CLOCAL); syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); running %s", dev,unit,redial_cmd); - if (!(modem_control & CLOCAL)) { - tty_orig.c_cflag |= CLOCAL; - if (tcsetattr(fd, TCSAFLUSH, &tty_orig) < 0) { - syslog(LOG_ERR, "tcsetattr(TCSAFLUSH): %m"); - exit_handler(1); - } - } system(redial_cmd); /* Now check again for carrier (dial command is done): */ if (!(modem_control & CLOCAL)) { @@ -390,50 +356,33 @@ again: } } } else { - /* - * No redial command. - * - * If modem control, just wait for carrier before - * falling through to setup_line() and attach_line(). - * If no modem control, just fall through immediately. - */ + /* 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: */ - while (! carrier) { - /* - * Don't burn the CPU checking for carrier; - * carrier must be polled since there is no - * way to have a signal sent when carrier - * goes high (SIGHUP can only be sent when - * carrier is dropped); so add space between - * checks for carrier: - */ - sleep(2); - - /* Check for carrier present on tty port: */ - ioctl(fd, TIOCMGET, &comstate); - if (comstate & TIOCM_CD) { - carrier = 1; + 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); + syslog(LOG_NOTICE, "Carrier now present on %s (sl%d)", + dev, unit); } } - setup_line(); - attach_line(); + setup_line(0); + slip_discipline(); + configure_network(); } /* Signal handler for SIGINT. We just log and exit. */ void sigint_handler() { if(exiting) return; - syslog(LOG_NOTICE,"sl%d on %s caught SIGINT, exiting.",unit,dev); + syslog(LOG_NOTICE,"SIGINT on %s (sl%d); exiting",dev,unit); exit_handler(0); } /* Signal handler for SIGTERM. We just log and exit. */