Initial revision

1 files changed, 1445 insertions, 0 deletions

diff --git a/usr.sbin/pppd/main.c b/usr.sbin/pppd/main.c
new file mode 100644
index 0000000..1e1397e
--- /dev/null
+++ b/usr.sbin/pppd/main.c
@@ -0,0 +1,1445 @@
+/*
+ * main.c - Point-to-Point Protocol main module
+ *
+ * Copyright (c) 1989 Carnegie Mellon University.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by Carnegie Mellon University.  The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#ifndef lint
+static char rcsid[] = "$Id: main.c,v 1.13 1994/05/27 01:02:14 paulus Exp $";
+#endif
+
+#define SETSID
+
+#include <stdio.h>
+#include <string.h>
+#include <signal.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <syslog.h>
+#include <netdb.h>
+#include <utmp.h>
+#include <pwd.h>
+#include <sys/wait.h>
+
+/*
+ * If REQ_SYSOPTIONS is defined to 1, pppd will not run unless
+ * /etc/ppp/options exists.
+ */
+#ifndef	REQ_SYSOPTIONS
+#define REQ_SYSOPTIONS	1
+#endif
+
+#ifdef SGTTY
+#include <sgtty.h>
+#else
+#ifndef sun
+#include <sys/ioctl.h>
+#endif
+#include <termios.h>
+#endif
+
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <net/if.h>
+
+#include "callout.h"
+#include "ppp.h"
+#include "magic.h"
+#include "fsm.h"
+#include "lcp.h"
+#include "ipcp.h"
+#include "upap.h"
+#include "chap.h"
+
+#include "pppd.h"
+#include "pathnames.h"
+#include "patchlevel.h"
+
+
+#ifndef TRUE
+#define TRUE (1)
+#endif /*TRUE*/
+
+#ifndef FALSE
+#define FALSE (0)
+#endif /*FALSE*/
+
+#ifdef PIDPATH
+static char *pidpath = PIDPATH;	/* filename in which pid will be stored */
+#else
+static char *pidpath = _PATH_PIDFILE;
+#endif /* PIDFILE */
+
+/* interface vars */
+char ifname[IFNAMSIZ];		/* Interface name */
+int ifunit;			/* Interface unit number */
+
+char *progname;			/* Name of this program */
+char hostname[MAXNAMELEN];	/* Our hostname */
+char our_name[MAXNAMELEN];
+char remote_name[MAXNAMELEN];
+static char pidfilename[MAXPATHLEN];
+
+static pid_t	pid;		/* Our pid */
+static pid_t	pgrpid;		/* Process Group ID */
+uid_t uid;			/* Our real user-id */
+
+char devname[MAXPATHLEN] = "/dev/tty";	/* Device name */
+int default_device = TRUE;	/* use default device (stdin/out) */
+
+int fd = -1;			/* Device file descriptor */
+int s;				/* Socket file descriptor */
+
+int phase;			/* where the link is at */
+
+#ifdef SGTTY
+static struct sgttyb initsgttyb;	/* Initial TTY sgttyb */
+#else
+static struct termios inittermios;	/* Initial TTY termios */
+#endif
+
+static int initfdflags = -1;	/* Initial file descriptor flags */
+
+static int restore_term;	/* 1 => we've munged the terminal */
+
+u_char outpacket_buf[MTU+DLLHEADERLEN]; /* buffer for outgoing packet */
+static u_char inpacket_buf[MTU+DLLHEADERLEN]; /* buffer for incoming packet */
+
+int hungup;			/* terminal has been hung up */
+static int n_children;		/* # child processes still running */
+
+/* configured variables */
+
+int debug = 0;		        /* Debug flag */
+int kdebugflag = 0;		/* Kernel debugging flag */
+char user[MAXNAMELEN];		/* username for PAP */
+char passwd[MAXSECRETLEN];	/* password for PAP */
+char *connector = NULL;		/* "connect" command */
+char *disconnector = NULL;	/* "disconnect" command */
+int inspeed = 0;		/* Input/Output speed requested */
+int baud_rate;			/* bits/sec currently used */
+u_long netmask = 0;		/* netmask to use on ppp interface */
+int crtscts = 0;		/* use h/w flow control */
+int nodetach = 0;		/* don't fork */
+int modem = 0;			/* use modem control lines */
+int auth_required = 0;		/* require peer to authenticate */
+int defaultroute = 0;		/* assign default route through interface */
+int proxyarp = 0;		/* set entry in arp table */
+int persist = 0;		/* re-initiate on termination */
+int answer = 0;			/* wait for incoming call */
+int uselogin = 0;		/* check PAP info against /etc/passwd */
+int lockflag = 0;		/* lock the serial device */
+
+
+/* prototypes */
+static void hup __ARGS((int));
+static void intr __ARGS((int));
+static void term __ARGS((int));
+static void alrm __ARGS((int));
+static void io __ARGS((int));
+static void chld __ARGS((int));
+static void incdebug __ARGS((int));
+static void nodebug __ARGS((int));
+void establish_ppp __ARGS((void));
+
+void reap_kids __ARGS((void));
+void cleanup __ARGS((int, caddr_t));
+void die __ARGS((int));
+void novm __ARGS((char *));
+
+void log_packet __ARGS((u_char *, int, char *));
+void format_packet __ARGS((u_char *, int,
+			   void (*) (void *, char *, ...), void *));
+void pr_log __ARGS((void *, char *, ...));
+
+extern	char	*ttyname __ARGS((int));
+extern	char	*getlogin __ARGS((void));
+
+/*
+ * PPP Data Link Layer "protocol" table.
+ * One entry per supported protocol.
+ */
+static struct protent {
+    u_short protocol;
+    void (*init)();
+    void (*input)();
+    void (*protrej)();
+    int  (*printpkt)();
+    char *name;
+} prottbl[] = {
+    { LCP, lcp_init, lcp_input, lcp_protrej, lcp_printpkt, "LCP" },
+    { IPCP, ipcp_init, ipcp_input, ipcp_protrej, ipcp_printpkt, "IPCP" },
+    { UPAP, upap_init, upap_input, upap_protrej, upap_printpkt, "PAP" },
+    { CHAP, ChapInit, ChapInput, ChapProtocolReject, ChapPrintPkt, "CHAP" },
+};
+
+#define N_PROTO		(sizeof(prottbl) / sizeof(prottbl[0]))
+
+main(argc, argv)
+    int argc;
+    char *argv[];
+{
+    int mask, i;
+    struct sigaction sa;
+    struct cmd *cmdp;
+    FILE *pidfile;
+    char *p;
+    struct passwd *pw;
+
+    p = ttyname(0);
+    if (p)
+	strcpy(devname, p);
+  
+    if (gethostname(hostname, MAXNAMELEN) < 0 ) {
+	perror("couldn't get hostname");
+	die(1);
+    }
+    hostname[MAXNAMELEN-1] = 0;
+
+    pid = getpid();
+    uid = getuid();
+
+    if (!ppp_available()) {
+	fprintf(stderr, "Sorry - PPP is not available on this system\n");
+	exit(1);
+    }
+
+    /*
+     * Initialize to the standard option set, then parse, in order,
+     * the system options file, the user's options file, and the command
+     * line arguments.
+     */
+    for (i = 0; i < N_PROTO; i++)
+	(*prottbl[i].init)(0);
+  
+    progname = *argv;
+
+    if (!options_from_file(_PATH_SYSOPTIONS, REQ_SYSOPTIONS, 0) ||
+	!options_from_user() ||
+	!parse_args(argc-1, argv+1) ||
+	!options_for_tty())
+	die(1);
+    check_auth_options();
+    setipdefault();
+
+    /*
+     * Initialize syslog system and magic number package.
+     */
+#if !defined(ultrix)
+    openlog("pppd", LOG_PID | LOG_NDELAY, LOG_PPP);
+    setlogmask(LOG_UPTO(LOG_INFO));
+#else
+    openlog("pppd", LOG_PID);
+#define LOG_UPTO(x) (x)
+#define setlogmask(x) (x)
+#endif
+    if (debug)
+	setlogmask(LOG_UPTO(LOG_DEBUG));
+
+    magic_init();
+
+    p = getlogin();
+    if (p == NULL) {
+	pw = getpwuid(uid);
+	if (pw != NULL && pw->pw_name != NULL)
+	    p = pw->pw_name;
+	else
+	    p = "(unknown)";
+    }
+    syslog(LOG_NOTICE, "pppd %s.%d started by %s, uid %d",
+	   VERSION, PATCHLEVEL, p, uid);
+
+#ifdef SETSID
+    /*
+     * Make sure we can set the serial device to be our controlling terminal.
+     */
+    if (default_device) {
+	/*
+	 * No device name was specified:
+	 * we are in the device's session already.
+	 */
+	if ((pgrpid = getpgrp(0)) < 0) {
+	    syslog(LOG_ERR, "getpgrp(0): %m");
+	    die(1);
+	}
+
+    } else {
+	/*
+	 * Not default device: make sure we're not a process group leader,
+	 * then become session leader of a new session (so we can make
+	 * our device its controlling terminal and thus get SIGHUPs).
+	 */
+	if (!nodetach) {
+	    /* fork so we're not a process group leader */
+	    if (pid = fork()) {
+		exit(0);	/* parent is finished */
+	    }
+	    if (pid < 0) {
+		syslog(LOG_ERR, "fork: %m");
+		die(1);
+	    }
+	    pid = getpid();	/* otherwise pid is 0 in child */
+	} else {
+	    /*
+	     * try to put ourself into our parent's process group,
+	     * so we're not a process group leader
+	     */
+	    if (setpgrp(pid, getppid()) < 0)
+		syslog(LOG_WARNING, "setpgrp: %m");
+	}
+
+	/* create new session */
+	if ((pgrpid = setsid()) < 0) {
+	    syslog(LOG_ERR, "setsid(): %m");
+	    die(1);
+	}
+    }
+#endif
+
+    if (lockflag && !default_device)
+	if (lock(devname) < 0)
+	    die(1);
+
+    /* Get an internet socket for doing socket ioctl's on. */
+    if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+	syslog(LOG_ERR, "socket : %m");
+	die(1);
+    }
+  
+    /*
+     * Compute mask of all interesting signals and install signal handlers
+     * for each.  Only one signal handler may be active at a time.  Therefore,
+     * all other signals should be masked when any handler is executing.
+     */
+    sigemptyset(&mask);
+    sigaddset(&mask, SIGHUP);
+    sigaddset(&mask, SIGINT);
+    sigaddset(&mask, SIGALRM);
+    sigaddset(&mask, SIGIO);
+    sigaddset(&mask, SIGCHLD);
+#ifdef	STREAMS
+    sigaddset(&mask, SIGPOLL);
+#endif
+
+#define SIGNAL(s, handler)	{ \
+	sa.sa_handler = handler; \
+	if (sigaction(s, &sa, NULL) < 0) { \
+	    syslog(LOG_ERR, "sigaction(%d): %m", s); \
+	    die(1); \
+	} \
+    }
+
+    sa.sa_mask = mask;
+    sa.sa_flags = 0;
+    SIGNAL(SIGHUP, hup);		/* Hangup */
+    SIGNAL(SIGINT, intr);		/* Interrupt */
+    SIGNAL(SIGTERM, term);		/* Terminate */
+    SIGNAL(SIGALRM, alrm);		/* Timeout */
+    SIGNAL(SIGIO, io);			/* Input available */
+    SIGNAL(SIGCHLD, chld);		/* Death of child process */
+#ifdef	STREAMS
+    SIGNAL(SIGPOLL, io);		/* Input available */
+#endif
+
+    signal(SIGUSR1, incdebug);		/* Increment debug flag */
+    signal(SIGUSR2, nodebug);		/* Reset debug flag */
+
+    /*
+     * Block SIGIOs and SIGPOLLs for now
+     */
+    sigemptyset(&mask);
+    sigaddset(&mask, SIGIO);
+#ifdef	STREAMS
+    sigaddset(&mask, SIGPOLL);
+#endif
+    sigprocmask(SIG_BLOCK, &mask, NULL);
+
+    /*
+     * Open the serial device and set it up to be the ppp interface.
+     */
+    if ((fd = open(devname, O_RDWR /*| O_NDELAY*/)) < 0) {
+	syslog(LOG_ERR, "open(%s): %m", devname);
+	die(1);
+    }
+    hungup = 0;
+
+#ifdef TIOCSCTTY
+    /* set device to be controlling tty */
+    if (!default_device && ioctl(fd, TIOCSCTTY) < 0) {
+	syslog(LOG_ERR, "ioctl(TIOCSCTTY): %m");
+	die(1);
+    }
+#endif /* TIOCSCTTY */
+
+    /* run connection script */
+    if (connector) {
+	MAINDEBUG((LOG_INFO, "Connecting with <%s>", connector));
+
+	/* set line speed, flow control, etc.; set CLOCAL for now */
+	set_up_tty(fd, 1);
+
+	/* drop dtr to hang up in case modem is off hook */
+	if (!default_device && modem) {
+	    setdtr(fd, FALSE);
+	    sleep(1);
+	    setdtr(fd, TRUE);
+	}
+
+	if (device_script(connector, fd, fd) < 0) {
+	    syslog(LOG_ERR, "could not set up connection");
+	    setdtr(fd, FALSE);
+	    die(1);
+	}
+
+	syslog(LOG_INFO, "Connected...");
+	sleep(1);		/* give it time to set up its terminal */
+    }
+  
+    /* set line speed, flow control, etc.; clear CLOCAL if modem option */
+    set_up_tty(fd, 0);
+
+    /* set up the serial device as a ppp interface */
+    establish_ppp();
+
+    syslog(LOG_INFO, "Using interface ppp%d", ifunit);
+    (void) sprintf(ifname, "ppp%d", ifunit);
+
+    /* write pid to file */
+    (void) sprintf(pidfilename, "%s/%s.pid", pidpath, ifname);
+    if ((pidfile = fopen(pidfilename, "w")) != NULL) {
+	fprintf(pidfile, "%d\n", pid);
+	(void) fclose(pidfile);
+    } else {
+	syslog(LOG_ERR, "unable to create pid file: %m");
+	pidfilename[0] = 0;
+    }
+
+    /*
+     * Set process group of device to our process group so we can get
+     * SIGIOs and SIGHUPs.
+     */
+#ifdef SETSID
+    if (default_device) {
+	int id = tcgetpgrp(fd);
+	if (id != pgrpid) {
+	    syslog(LOG_WARNING, "warning: not in tty's process group");
+	}
+    } else {
+	if (tcsetpgrp(fd, pgrpid) < 0) {
+	    syslog(LOG_ERR, "tcsetpgrp(): %m");
+	    die(1);
+	}
+    }
+#else
+    /* set process group on tty so we get SIGIO's */
+    if (ioctl(fd, TIOCSPGRP, &pgrpid) < 0) {
+	syslog(LOG_ERR, "ioctl(TIOCSPGRP): %m");
+	die(1);
+    }
+#endif
+
+    /*
+     * Record initial device flags, then set device to cause SIGIO
+     * signals to be generated.
+     */
+    if ((initfdflags = fcntl(fd, F_GETFL)) == -1) {
+	syslog(LOG_ERR, "fcntl(F_GETFL): %m");
+	die(1);
+    }
+
+#ifdef _linux_ /* This is a kludge for Linux. FIXME !!! -- later. */
+#undef	FASYNC
+#define FASYNC	0
+#endif
+
+    if (fcntl(fd, F_SETFL, FNDELAY | FASYNC) == -1) {
+	syslog(LOG_ERR, "fcntl(F_SETFL, FNDELAY | FASYNC): %m");
+	die(1);
+    }
+  
+    /*
+     * Block all signals, start opening the connection, and  wait for
+     * incoming signals (reply, timeout, etc.).
+     */
+    syslog(LOG_NOTICE, "Connect: %s <--> %s", ifname, devname);
+    sigprocmask(SIG_BLOCK, &mask, NULL); /* Block signals now */
+    lcp_lowerup(0);		/* XXX Well, sort of... */
+    lcp_open(0);		/* Start protocol */
+    for (phase = PHASE_ESTABLISH; phase != PHASE_DEAD; )
+	sigpause(0);		/* Wait for next signal */
+
+    /*
+     * Run disconnector script, if requested
+     */
+    if (disconnector) {
+	if (device_script(disconnector, fd, fd) < 0) {
+	    syslog(LOG_WARNING, "disconnect script failed");
+	    die(1);
+	}
+
+	syslog(LOG_INFO, "Disconnected...");
+    }
+
+    quit();
+}
+
+#if B9600 == 9600
+/*
+ * XXX assume speed_t values numerically equal bits per second
+ * (so we can ask for any speed).
+ */
+#define translate_speed(bps)	(bps)
+#define baud_rate_of(speed)	(speed)
+
+#else
+/*
+ * List of valid speeds.
+ */
+struct speed {
+    int speed_int, speed_val;
+} speeds[] = {
+#ifdef B50
+    { 50, B50 },
+#endif
+#ifdef B75
+    { 75, B75 },
+#endif
+#ifdef B110
+    { 110, B110 },
+#endif
+#ifdef B134
+    { 134, B134 },
+#endif
+#ifdef B150
+    { 150, B150 },
+#endif
+#ifdef B200
+    { 200, B200 },
+#endif
+#ifdef B300
+    { 300, B300 },
+#endif
+#ifdef B600
+    { 600, B600 },
+#endif
+#ifdef B1200
+    { 1200, B1200 },
+#endif
+#ifdef B1800
+    { 1800, B1800 },
+#endif
+#ifdef B2000
+    { 2000, B2000 },
+#endif
+#ifdef B2400
+    { 2400, B2400 },
+#endif
+#ifdef B3600
+    { 3600, B3600 },
+#endif
+#ifdef B4800
+    { 4800, B4800 },
+#endif
+#ifdef B7200
+    { 7200, B7200 },
+#endif
+#ifdef B9600
+    { 9600, B9600 },
+#endif
+#ifdef B19200
+    { 19200, B19200 },
+#endif
+#ifdef B38400
+    { 38400, B38400 },
+#endif
+#ifdef EXTA
+    { 19200, EXTA },
+#endif
+#ifdef EXTB
+    { 38400, EXTB },
+#endif
+#ifdef B57600
+    { 57600, B57600 },
+#endif
+#ifdef B115200
+    { 115200, B115200 },
+#endif
+    { 0, 0 }
+};
+
+/*
+ * Translate from bits/second to a speed_t.
+ */
+int
+translate_speed(bps)
+    int bps;
+{
+    struct speed *speedp;
+
+    if (bps == 0)
+	return 0;
+    for (speedp = speeds; speedp->speed_int; speedp++)
+	if (bps == speedp->speed_int)
+	    return speedp->speed_val;
+    syslog(LOG_WARNING, "speed %d not supported", bps);
+    return 0;
+}
+
+/*
+ * Translate from a speed_t to bits/second.
+ */
+int
+baud_rate_of(speed)
+    int speed;
+{
+    struct speed *speedp;
+
+    if (speed == 0)
+	return 0;
+    for (speedp = speeds; speedp->speed_int; speedp++)
+	if (speed == speedp->speed_val)
+	    return speedp->speed_int;
+    return 0;
+}
+#endif
+
+/*
+ * set_up_tty: Set up the serial port on `fd' for 8 bits, no parity,
+ * at the requested speed, etc.  If `local' is true, set CLOCAL
+ * regardless of whether the modem option was specified.
+ */
+set_up_tty(fd, local)
+    int fd, local;
+{
+#ifndef SGTTY
+    int speed, x;
+    struct termios tios;
+
+    if (tcgetattr(fd, &tios) < 0) {
+	syslog(LOG_ERR, "tcgetattr: %m");
+	die(1);
+    }
+
+    if (!restore_term)
+	inittermios = tios;
+
+#ifdef CRTSCTS
+    tios.c_cflag &= ~(CSIZE | CSTOPB | PARENB | CLOCAL | CRTSCTS);
+    if (crtscts == 1)
+	tios.c_cflag |= CRTSCTS;
+#else
+    tios.c_cflag &= ~(CSIZE | CSTOPB | PARENB | CLOCAL);
+#endif	/* CRTSCTS */
+
+    tios.c_cflag |= CS8 | CREAD | HUPCL;
+    if (local || !modem)
+	tios.c_cflag |= CLOCAL;
+    tios.c_iflag = IGNBRK | IGNPAR;
+    tios.c_oflag = 0;
+    tios.c_lflag = 0;
+    tios.c_cc[VMIN] = 1;
+    tios.c_cc[VTIME] = 0;
+
+    if (crtscts == 2) {
+	tios.c_iflag |= IXOFF;
+	tios.c_cc[VSTOP] = 0x13;	/* DC3 = XOFF = ^S */
+	tios.c_cc[VSTART] = 0x11;	/* DC1 = XON  = ^Q */
+    }
+
+    speed = translate_speed(inspeed);
+    if (speed) {
+	cfsetospeed(&tios, speed);
+	cfsetispeed(&tios, speed);
+    } else {
+	speed = cfgetospeed(&tios);
+    }
+
+    if (tcsetattr(fd, TCSAFLUSH, &tios) < 0) {
+	syslog(LOG_ERR, "tcsetattr: %m");
+	die(1);
+    }
+
+#ifdef ultrix
+    x = 0;
+    if (ioctl(fd, (crtscts || modem)? TIOCMODEM: TIOCNMODEM, &x) < 0)
+	syslog(LOG_WARNING, "TIOC(N)MODEM: %m");
+    if (ioctl(fd, (local || !modem)? TIOCNCAR: TIOCCAR) < 0)
+	syslog(LOG_WARNING, "TIOC(N)CAR: %m");
+#endif
+
+#else	/* SGTTY */
+    int speed;
+    struct sgttyb sgttyb;
+
+    /*
+     * Put the tty in raw mode.
+     */
+    if (ioctl(fd, TIOCGETP, &sgttyb) < 0) {
+	syslog(LOG_ERR, "ioctl(TIOCGETP): %m");
+	die(1);
+    }
+
+    if (!restore_term)
+	initsgttyb = sgttyb;
+
+    sgttyb.sg_flags = RAW | ANYP;
+    speed = translate_speed(inspeed);
+    if (speed)
+	sgttyb.sg_ispeed = speed;
+    else
+	speed = sgttyb.sg_ispeed;
+
+    if (ioctl(fd, TIOCSETP, &sgttyb) < 0) {
+	syslog(LOG_ERR, "ioctl(TIOCSETP): %m");
+	die(1);
+    }
+#endif
+
+    baud_rate = baud_rate_of(speed);
+    restore_term = TRUE;
+}
+
+/*
+ * setdtr - control the DTR line on the serial port.
+ * This is called from die(), so it shouldn't call die().
+ */
+setdtr(fd, on)
+int fd, on;
+{
+    int modembits = TIOCM_DTR;
+
+    ioctl(fd, (on? TIOCMBIS: TIOCMBIC), &modembits);
+}
+
+
+/*
+ * quit - Clean up state and exit.
+ */
+void 
+quit()
+{
+    die(0);
+}
+
+/*
+ * die - like quit, except we can specify an exit status.
+ */
+void
+die(status)
+    int status;
+{
+    cleanup(0, NULL);
+    syslog(LOG_INFO, "Exit.");
+    exit(status);
+}
+
+/*
+ * cleanup - restore anything which needs to be restored before we exit
+ */
+/* ARGSUSED */
+void
+cleanup(status, arg)
+    int status;
+    caddr_t arg;
+{
+    if (fd >= 0) {
+	/* drop dtr to hang up */
+	if (modem)
+	    setdtr(fd, FALSE);
+
+	if (initfdflags != -1 && fcntl(fd, F_SETFL, initfdflags) < 0)
+	    syslog(LOG_WARNING, "fcntl(F_SETFL, fdflags): %m");
+	initfdflags = -1;
+
+	disestablish_ppp();
+
+	if (restore_term) {
+#ifndef SGTTY
+	    if (tcsetattr(fd, TCSAFLUSH, &inittermios) < 0)
+		syslog(LOG_WARNING, "tcsetattr: %m");
+#else
+	    if (ioctl(fd, TIOCSETP, &initsgttyb) < 0)
+		syslog(LOG_WARNING, "ioctl(TIOCSETP): %m");
+#endif
+	}
+
+	close(fd);
+	fd = -1;
+    }
+
+    if (pidfilename[0] != 0 && unlink(pidfilename) < 0) 
+	syslog(LOG_WARNING, "unable to unlink pid file: %m");
+    pidfilename[0] = 0;
+
+    if (lockflag && !default_device)
+	unlock();
+}
+
+
+static struct callout *callout = NULL;		/* Callout list */
+static struct timeval schedtime;		/* Time last timeout was set */
+
+/*
+ * timeout - Schedule a timeout.
+ *
+ * Note that this timeout takes the number of seconds, NOT hz (as in
+ * the kernel).
+ */
+void
+timeout(func, arg, time)
+    void (*func)();
+    caddr_t arg;
+    int time;
+{
+    struct itimerval itv;
+    struct callout *newp, **oldpp;
+  
+    MAINDEBUG((LOG_DEBUG, "Timeout %x:%x in %d seconds.",
+	       (int) func, (int) arg, time));
+  
+    /*
+     * Allocate timeout.
+     */
+    if ((newp = (struct callout *) malloc(sizeof(struct callout))) == NULL) {
+	syslog(LOG_ERR, "Out of memory in timeout()!");
+	die(1);
+    }
+    newp->c_arg = arg;
+    newp->c_func = func;
+  
+    /*
+     * Find correct place to link it in and decrement its time by the
+     * amount of time used by preceding timeouts.
+     */
+    for (oldpp = &callout;
+	 *oldpp && (*oldpp)->c_time <= time;
+	 oldpp = &(*oldpp)->c_next)
+	time -= (*oldpp)->c_time;
+    newp->c_time = time;
+    newp->c_next = *oldpp;
+    if (*oldpp)
+	(*oldpp)->c_time -= time;
+    *oldpp = newp;
+  
+    /*
+     * If this is now the first callout then we have to set a new
+     * itimer.
+     */
+    if (callout == newp) {
+	itv.it_interval.tv_sec = itv.it_interval.tv_usec =
+	    itv.it_value.tv_usec = 0;
+	itv.it_value.tv_sec = callout->c_time;
+	MAINDEBUG((LOG_DEBUG, "Setting itimer for %d seconds in timeout.",
+		   itv.it_value.tv_sec));
+	if (setitimer(ITIMER_REAL, &itv, NULL)) {
+	    syslog(LOG_ERR, "setitimer(ITIMER_REAL): %m");
+	    die(1);
+	}
+	if (gettimeofday(&schedtime, NULL)) {
+	    syslog(LOG_ERR, "gettimeofday: %m");
+	    die(1);
+	}
+    }
+}
+
+
+/*
+ * untimeout - Unschedule a timeout.
+ */
+void
+untimeout(func, arg)
+    void (*func)();
+    caddr_t arg;
+{
+    struct itimerval itv;
+    struct callout **copp, *freep;
+    int reschedule = 0;
+  
+    MAINDEBUG((LOG_DEBUG, "Untimeout %x:%x.", (int) func, (int) arg));
+  
+    /*
+     * If the first callout is unscheduled then we have to set a new
+     * itimer.
+     */
+    if (callout &&
+	callout->c_func == func &&
+	callout->c_arg == arg)
+	reschedule = 1;
+  
+    /*
+     * Find first matching timeout.  Add its time to the next timeouts
+     * time.
+     */
+    for (copp = &callout; *copp; copp = &(*copp)->c_next)
+	if ((*copp)->c_func == func &&
+	    (*copp)->c_arg == arg) {
+	    freep = *copp;
+	    *copp = freep->c_next;
+	    if (*copp)
+		(*copp)->c_time += freep->c_time;
+	    (void) free((char *) freep);
+	    break;
+	}
+  
+    if (reschedule) {
+	itv.it_interval.tv_sec = itv.it_interval.tv_usec =
+	    itv.it_value.tv_usec = 0;
+	itv.it_value.tv_sec = callout ? callout->c_time : 0;
+	MAINDEBUG((LOG_DEBUG, "Setting itimer for %d seconds in untimeout.",
+		   itv.it_value.tv_sec));
+	if (setitimer(ITIMER_REAL, &itv, NULL)) {
+	    syslog(LOG_ERR, "setitimer(ITIMER_REAL): %m");
+	    die(1);
+	}
+	if (gettimeofday(&schedtime, NULL)) {
+	    syslog(LOG_ERR, "gettimeofday: %m");
+	    die(1);
+	}
+    }
+}
+
+
+/*
+ * adjtimeout - Decrement the first timeout by the amount of time since
+ * it was scheduled.
+ */
+void
+adjtimeout()
+{
+    struct timeval tv;
+    int timediff;
+  
+    if (callout == NULL)
+	return;
+    /*
+     * Make sure that the clock hasn't been warped dramatically.
+     * Account for recently expired, but blocked timer by adding
+     * small fudge factor.
+     */
+    if (gettimeofday(&tv, NULL)) {
+	syslog(LOG_ERR, "gettimeofday: %m");
+	die(1);
+    }
+    timediff = tv.tv_sec - schedtime.tv_sec;
+    if (timediff < 0 ||
+	timediff > callout->c_time + 1)
+	return;
+  
+    callout->c_time -= timediff;	/* OK, Adjust time */
+}
+
+
+/*
+ * hup - Catch SIGHUP signal.
+ *
+ * Indicates that the physical layer has been disconnected.
+ */
+static void
+hup(sig)
+    int sig;
+{
+    syslog(LOG_INFO, "Hangup (SIGHUP)");
+
+    hungup = 1;			/* they hung up on us! */
+    persist = 0;		/* don't try to restart */
+    adjtimeout();		/* Adjust timeouts */
+    lcp_lowerdown(0);		/* Reset connection */
+    quit();			/* and die */
+}
+
+
+/*
+ * term - Catch SIGTERM signal.
+ *
+ * Indicates that we should initiate a graceful disconnect and exit.
+ */
+static void
+term(sig)
+    int sig;
+{
+    syslog(LOG_INFO, "Terminating link.");
+    persist = 0;		/* don't try to restart */
+    adjtimeout();		/* Adjust timeouts */
+    lcp_close(0);		/* Close connection */
+}
+
+
+/*
+ * intr - Catch SIGINT signal (DEL/^C).
+ *
+ * Indicates that we should initiate a graceful disconnect and exit.
+ */
+static void
+intr(sig)
+    int sig;
+{
+    syslog(LOG_INFO, "Interrupt received: terminating link");
+    persist = 0;		/* don't try to restart */
+    adjtimeout();		/* Adjust timeouts */
+    lcp_close(0);		/* Close connection */
+}
+
+
+/*
+ * alrm - Catch SIGALRM signal.
+ *
+ * Indicates a timeout.
+ */
+static void
+alrm(sig)
+    int sig;
+{
+    struct itimerval itv;
+    struct callout *freep, *list, *last;
+
+    MAINDEBUG((LOG_DEBUG, "Alarm"));
+
+    if (callout == NULL)
+	return;
+    /*
+     * Get the first scheduled timeout and any that were scheduled
+     * for the same time as a list, and remove them all from callout
+     * list.
+     */
+    list = last = callout;
+    while (last->c_next != NULL && last->c_next->c_time == 0)
+	last = last->c_next;
+    callout = last->c_next;
+    last->c_next = NULL;
+
+    /*
+     * Set a new itimer if there are more timeouts scheduled.
+     */
+    if (callout) {
+	itv.it_interval.tv_sec = itv.it_interval.tv_usec = 0;
+	itv.it_value.tv_usec = 0;
+	itv.it_value.tv_sec = callout->c_time;
+	MAINDEBUG((LOG_DEBUG, "Setting itimer for %d seconds in alrm.",
+		   itv.it_value.tv_sec));
+	if (setitimer(ITIMER_REAL, &itv, NULL)) {
+	    syslog(LOG_ERR, "setitimer(ITIMER_REAL): %m");
+	    die(1);
+	}
+	if (gettimeofday(&schedtime, NULL)) {
+	    syslog(LOG_ERR, "gettimeofday: %m");
+	    die(1);
+	}
+    }
+
+    /*
+     * Now call all the timeout routines scheduled for this time.
+     */
+    while (list) {
+	(*list->c_func)(list->c_arg);
+	freep = list;
+	list = list->c_next;
+	(void) free((char *) freep);
+    }
+  
+}
+
+
+/*
+ * chld - Catch SIGCHLD signal.
+ * Calls reap_kids to get status for any dead kids.
+ */
+static void
+chld(sig)
+    int sig;
+{
+    reap_kids();
+}
+
+
+/*
+ * io - Catch SIGIO signal.
+ *
+ * Indicates that incoming data is available.
+ */
+static void
+io(sig)
+    int sig;
+{
+    int len, i;
+    u_char *p;
+    u_short protocol;
+    fd_set fdset;
+    struct timeval notime;
+    int ready;
+
+    MAINDEBUG((LOG_DEBUG, "IO signal received"));
+    adjtimeout();		/* Adjust timeouts */
+
+    /* Yup, this is for real */
+    for (;;) {			/* Read all available packets */
+	p = inpacket_buf;	/* point to beginning of packet buffer */
+
+	len = read_packet(inpacket_buf);
+	if (len < 0)
+	    return;
+
+	if (len == 0) {
+	    MAINDEBUG((LOG_DEBUG, "End of file on fd!"));
+	    lcp_lowerdown(0);
+	    return;
+	}
+
+	if (debug /*&& (debugflags & DBG_INPACKET)*/)
+	    log_packet(p, len, "rcvd ");
+
+	if (len < DLLHEADERLEN) {
+	    MAINDEBUG((LOG_INFO, "io(): Received short packet."));
+	    return;
+	}
+
+	p += 2;				/* Skip address and control */
+	GETSHORT(protocol, p);
+	len -= DLLHEADERLEN;
+
+	/*
+	 * Toss all non-LCP packets unless LCP is OPEN.
+	 */
+	if (protocol != LCP && lcp_fsm[0].state != OPENED) {
+	    MAINDEBUG((LOG_INFO,
+		       "io(): Received non-LCP packet when LCP not open."));
+	    return;
+	}
+
+	/*
+	 * Upcall the proper protocol input routine.
+	 */
+	for (i = 0; i < sizeof (prottbl) / sizeof (struct protent); i++)
+	    if (prottbl[i].protocol == protocol) {
+		(*prottbl[i].input)(0, p, len);
+		break;
+	    }
+
+	if (i == sizeof (prottbl) / sizeof (struct protent)) {
+	    syslog(LOG_WARNING, "input: Unknown protocol (%x) received!",
+		   protocol);
+	    lcp_sprotrej(0, p - DLLHEADERLEN, len + DLLHEADERLEN);
+	}
+    }
+}
+
+/*
+ * demuxprotrej - Demultiplex a Protocol-Reject.
+ */
+void
+demuxprotrej(unit, protocol)
+    int unit;
+    u_short protocol;
+{
+    int i;
+
+    /*
+     * Upcall the proper Protocol-Reject routine.
+     */
+    for (i = 0; i < sizeof (prottbl) / sizeof (struct protent); i++)
+	if (prottbl[i].protocol == protocol) {
+	    (*prottbl[i].protrej)(unit);
+	    return;
+	}
+
+    syslog(LOG_WARNING,
+	   "demuxprotrej: Unrecognized Protocol-Reject for protocol %d!",
+	   protocol);
+}
+
+
+/*
+ * incdebug - Catch SIGUSR1 signal.
+ *
+ * Increment debug flag.
+ */
+/*ARGSUSED*/
+static void
+incdebug(sig)
+    int sig;
+{
+    syslog(LOG_INFO, "Debug turned ON, Level %d", debug);
+    setlogmask(LOG_UPTO(LOG_DEBUG));
+    debug++;
+}
+
+
+/*
+ * nodebug - Catch SIGUSR2 signal.
+ *
+ * Turn off debugging.
+ */
+/*ARGSUSED*/
+static void
+nodebug(sig)
+    int sig;
+{
+    setlogmask(LOG_UPTO(LOG_WARNING));
+    debug = 0;
+}
+
+
+/*
+ * device_script - run a program to connect or disconnect the
+ * serial device.
+ */
+int
+device_script(program, in, out)
+    char *program;
+    int in, out;
+{
+    int pid;
+    int status;
+    sigset_t mask;
+
+    sigemptyset(&mask);
+    sigaddset(&mask, SIGINT);
+    sigaddset(&mask, SIGHUP);
+    sigprocmask(SIG_BLOCK, &mask, &mask);
+
+    pid = fork();
+
+    if (pid < 0) {
+	syslog(LOG_ERR, "fork: %m");
+	die(1);
+    }
+
+    if (pid == 0) {
+	setreuid(getuid(), getuid());
+	setregid(getgid(), getgid());
+	sigprocmask(SIG_SETMASK, &mask, NULL);
+	dup2(in, 0);
+	dup2(out, 1);
+	execl("/bin/sh", "sh", "-c", program, (char *)0);
+	syslog(LOG_ERR, "could not exec /bin/sh: %m");
+	_exit(99);
+	/* NOTREACHED */
+    }
+
+    while (waitpid(pid, &status, 0) < 0) {
+	if (errno == EINTR)
+	    continue;
+	syslog(LOG_ERR, "waiting for (dis)connection process: %m");
+	die(1);
+    }
+    sigprocmask(SIG_SETMASK, &mask, NULL);
+
+    return (status == 0 ? 0 : -1);
+}
+
+
+/*
+ * run-program - execute a program with given arguments,
+ * but don't wait for it.
+ * If the program can't be executed, logs an error unless
+ * must_exist is 0 and the program file doesn't exist.
+ */
+int
+run_program(prog, args, must_exist)
+    char *prog;
+    char **args;
+    int must_exist;
+{
+    int pid;
+
+    pid = fork();
+    if (pid == -1) {
+	syslog(LOG_ERR, "can't fork to run %s: %m", prog);
+	return -1;
+    }
+    if (pid == 0) {
+	execv(prog, args);
+	if (must_exist || errno != ENOENT)
+	    syslog(LOG_WARNING, "can't execute %s: %m", prog);
+	_exit(-1);
+    }
+    MAINDEBUG((LOG_DEBUG, "Script %s started; pid = %d", prog, pid));
+    ++n_children;
+    return 0;
+}
+
+
+/*
+ * reap_kids - get status from any dead child processes,
+ * and log a message for abnormal terminations.
+ */
+void
+reap_kids()
+{
+    int pid, status;
+
+    if (n_children == 0)
+	return;
+    if ((pid = waitpid(-1, &status, WNOHANG)) == -1) {
+	if (errno != ECHILD)
+	    syslog(LOG_ERR, "waitpid: %m");
+	return;
+    }
+    if (pid > 0) {
+	--n_children;
+	if (WIFSIGNALED(status)) {
+	    syslog(LOG_WARNING, "child process %d terminated with signal %d",
+		   pid, WTERMSIG(status));
+	}
+    }
+}
+
+
+/*
+ * log_packet - format a packet and log it.
+ */
+
+char line[256];			/* line to be logged accumulated here */
+char *linep;
+
+void
+log_packet(p, len, prefix)
+    u_char *p;
+    int len;
+    char *prefix;
+{
+    strcpy(line, prefix);
+    linep = line + strlen(line);
+    format_packet(p, len, pr_log, NULL);
+    if (linep != line)
+	syslog(LOG_DEBUG, "%s", line);
+}
+
+/*
+ * format_packet - make a readable representation of a packet,
+ * calling `printer(arg, format, ...)' to output it.
+ */
+void
+format_packet(p, len, printer, arg)
+    u_char *p;
+    int len;
+    void (*printer) __ARGS((void *, char *, ...));
+    void *arg;
+{
+    int i, n;
+    u_short proto;
+    u_char x;
+
+    if (len >= DLLHEADERLEN && p[0] == ALLSTATIONS && p[1] == UI) {
+	p += 2;
+	GETSHORT(proto, p);
+	len -= DLLHEADERLEN;
+	for (i = 0; i < N_PROTO; ++i)
+	    if (proto == prottbl[i].protocol)
+		break;
+	if (i < N_PROTO) {
+	    printer(arg, "[%s", prottbl[i].name);
+	    n = (*prottbl[i].printpkt)(p, len, printer, arg);
+	    printer(arg, "]");
+	    p += n;
+	    len -= n;
+	} else {
+	    printer(arg, "[proto=0x%x]", proto);
+	}
+    }
+
+    for (; len > 0; --len) {
+	GETCHAR(x, p);
+	printer(arg, " %.2x", x);
+    }
+}
+
+#ifdef __STDC__
+#include <stdarg.h>
+
+void
+pr_log(void *arg, char *fmt, ...)
+{
+    int n;
+    va_list pvar;
+    char buf[256];
+
+    va_start(pvar, fmt);
+    vsprintf(buf, fmt, pvar);
+    va_end(pvar);
+
+    n = strlen(buf);
+    if (linep + n + 1 > line + sizeof(line)) {
+	syslog(LOG_DEBUG, "%s", line);
+	linep = line;
+    }
+    strcpy(linep, buf);
+    linep += n;
+}
+
+#else /* __STDC__ */
+#include <varargs.h>
+
+void
+pr_log(arg, fmt, va_alist)
+void *arg;
+char *fmt;
+va_dcl
+{
+    int n;
+    va_list pvar;
+    char buf[256];
+
+    va_start(pvar);
+    vsprintf(buf, fmt, pvar);
+    va_end(pvar);
+
+    n = strlen(buf);
+    if (linep + n + 1 > line + sizeof(line)) {
+	syslog(LOG_DEBUG, "%s", line);
+	linep = line;
+    }
+    strcpy(linep, buf);
+    linep += n;
+}
+#endif
+
+/*
+ * print_string - print a readable representation of a string using
+ * printer.
+ */
+void
+print_string(p, len, printer, arg)
+    char *p;
+    int len;
+    void (*printer) __ARGS((void *, char *, ...));
+    void *arg;
+{
+    int c;
+
+    printer(arg, "\"");
+    for (; len > 0; --len) {
+	c = *p++;
+	if (' ' <= c && c <= '~')
+	    printer(arg, "%c", c);
+	else
+	    printer(arg, "\\%.3o", c);
+    }
+    printer(arg, "\"");
+}
+
+/*
+ * novm - log an error message saying we ran out of memory, and die.
+ */
+void
+novm(msg)
+    char *msg;
+{
+    syslog(LOG_ERR, "Virtual memory exhausted allocating %s\n", msg);
+    die(1);
+}