rtemsmain.c

RTEMS (Real-Time Executive for Multiprocessor Systems) is a free open source real-time operating sys

/*
 * 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.
 */

#define RCSID	"$Id: rtemsmain.c,v 1.3.4.1 2003/04/10 13:09:09 joel Exp $"

#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <pwd.h>
#include <setjmp.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <netinet/in.h>

#include <rtems.h>
#include <rtems/rtems_bsdnet.h>

#include "pppd.h"
#include "magic.h"
#include "fsm.h"
#include "lcp.h"
#include "ipcp.h"
#ifdef INET6
#include "ipv6cp.h"
#endif
#include "upap.h"
#include "chap.h"
#include "ccp.h"
#include "pathnames.h"
#include "patchlevel.h"
#include "rtemsdialer.h"

#ifdef CBCP_SUPPORT
#include "cbcp.h"
#endif

#ifdef IPX_CHANGE
#include "ipxcp.h"
#endif /* IPX_CHANGE */
#ifdef AT_CHANGE
#include "atcp.h"
#endif

static const char rcsid[] = RCSID;

/* interface vars */
char ifname[32];		/* Interface name */
int pppifunit;			/* Interface unit number */

char hostname[MAXNAMELEN];	/* Our hostname */
static char ppp_devnam[MAXPATHLEN]; /* name of PPP tty (maybe ttypx) */

int ttyfd;			/* Serial port file descriptor */
int baud_rate;			/* Actual bits/second for serial device */
int hungup;			/* terminal has been hung up */
int privileged;			/* we're running as real uid root */
int need_holdoff;		/* need holdoff period before restarting */
int detached;			/* have detached from terminal */
struct stat devstat;		/* result of stat() on devnam */
int prepass = 0;		/* doing prepass to find device name */
int devnam_fixed;		/* set while in options.ttyxx file */
volatile int pppd_status;		/* exit status for pppd */
int unsuccess;			/* # unsuccessful connection attempts */
int do_callback;		/* != 0 if we should do callback next */
int doing_callback;		/* != 0 if we are doing callback */
char *callback_script;		/* script for doing callback */
dialerfp pppd_dialer;

int (*holdoff_hook) __P((void)) = NULL;
int (*new_phase_hook) __P((int)) = NULL;

static int fd_ppp = -1;		/* fd for talking PPP */
static int pty_master;		/* fd for master side of pty */
static int pty_slave;		/* fd for slave side of pty */
static int real_ttyfd;		/* fd for actual serial port (not pty) */

int pppd_phase;			/* where the link is at */
int pppd_kill_link;
int open_ccp_flag;

char **script_env;		/* Env. variable values for scripts */
int s_env_nalloc;		/* # words avail at script_env */

u_char outpacket_buf[PPP_MRU+PPP_HDRLEN]; /* buffer for outgoing packet */
u_char inpacket_buf[PPP_MRU+PPP_HDRLEN]; /* buffer for incoming packet */

char *no_ppp_msg = "Sorry - this system lacks PPP kernel support\n";

static struct timeval start_time;	/* Time when link was started. */

struct pppd_stats link_stats;
int link_connect_time;
int link_stats_valid;

/* Prototypes for procedures local to this file. */

static void cleanup __P((void));
static void close_tty __P((void));
static void get_input __P((void));
static void calltimeout __P((void));
static struct timeval *timeleft __P((struct timeval *));
static void holdoff_end __P((void *));
static int device_script __P((int, int, char *));

extern	char	*ttyname __P((int));
extern	char	*getlogin __P((void));
int pppdmain __P((int, char *[]));

/*
 * PPP Data Link Layer "protocol" table.
 * One entry per supported protocol.
 * The last entry must be NULL.
 */
struct protent *protocols[] = {
    &lcp_protent,
    &pap_protent,
    &chap_protent,
#ifdef CBCP_SUPPORT
    &cbcp_protent,
#endif
    &ipcp_protent,
#ifdef INET6
    &ipv6cp_protent,
#endif
    &ccp_protent,
#ifdef IPX_CHANGE
    &ipxcp_protent,
#endif
#ifdef AT_CHANGE
    &atcp_protent,
#endif
    NULL
};

int
pppdmain(argc, argv)
    int argc;
    char *argv[];
{
    int i, fdflags, t;
    char *connector;
    struct timeval timo;
    struct protent *protp;

    new_phase(PHASE_INITIALIZE);

    script_env = NULL;
    hostname[MAXNAMELEN-1] = 0;
    privileged = 1;
    privileged_option = 1;

    /*
     * Initialize magic number generator now so that protocols may
     * use magic numbers in initialization.
     */
    magic_init();

#ifdef XXX_XXX
    /* moved code the the rtems_pppd_reset_options function */

    /*
     * Initialize to the standard option set, then parse, in order,
     * the system options file, the user's options file,
     * the tty's options file, and the command line arguments.
     */
    for (i = 0; (protp = protocols[i]) != NULL; ++i)
        (*protp->init)(0);
#endif


    if (!ppp_available()) {
	option_error(no_ppp_msg);
	return(EXIT_NO_KERNEL_SUPPORT);
    }

    /*
     * Check that the options given are valid and consistent.
     */
    if (!sys_check_options()) {
	return(EXIT_OPTION_ERROR);
    }
    if (!auth_check_options()) {
	return(EXIT_OPTION_ERROR);
    }
    for (i = 0; (protp = protocols[i]) != NULL; ++i)
	if (protp->check_options != NULL)
	    (*protp->check_options)();

    /* default holdoff to 0 if no connect script has been given */
    if (connect_script == 0 && !holdoff_specified)
	holdoff = 0;

    if (default_device)
	nodetach = 1;

    /*
     * Initialize system-dependent stuff.
     */
    sys_init();
    /* if (debug)
	setlogmask(LOG_UPTO(LOG_DEBUG));
    */

    do_callback = 0;
    for (;;) {

	need_holdoff = 1;
	ttyfd = -1;
	real_ttyfd = -1;
	pppd_status = EXIT_OK;
	++unsuccess;
	doing_callback = do_callback;
	do_callback = 0;

	new_phase(PHASE_SERIALCONN);

	/*
	 * Get a pty master/slave pair if the pty, notty, or record
	 * options were specified.
	 */
	strlcpy(ppp_devnam, devnam, sizeof(ppp_devnam));
	pty_master = -1;
	pty_slave = -1;

	/*
	 * Open the serial device and set it up to be the ppp interface.
	 * First we open it in non-blocking mode so we can set the
	 * various termios flags appropriately.  If we aren't dialling
	 * out and we want to use the modem lines, we reopen it later
	 * in order to wait for the carrier detect signal from the modem.
	 */
	hungup = 0;
	pppd_kill_link = 0;
	connector = doing_callback? callback_script: connect_script;
	if (devnam[0] != 0) {
	    for (;;) {
		/* If the user specified the device name, become the
		   user before opening it. */
		int err;
		ttyfd = open(devnam, O_NONBLOCK | O_RDWR, 0);
		err = errno;
		if (ttyfd >= 0) {
		    break;
		}
		errno = err;
		if (err != EINTR) {
		    error("Failed to open %s: %m", devnam);
		    pppd_status = EXIT_OPEN_FAILED;
		}
		if (!persist || err != EINTR)
		    goto fail;
	    }
	    if ((fdflags = fcntl(ttyfd, F_GETFL)) == -1
		|| fcntl(ttyfd, F_SETFL, fdflags & ~O_NONBLOCK) < 0)
		warn("Couldn't reset non-blocking mode on device: %m");

	    /*
	     * Set line speed, flow control, etc.
	     * If we have a non-null connection or initializer script,
	     * on most systems we set CLOCAL for now so that we can talk
	     * to the modem before carrier comes up.  But this has the
	     * side effect that we might miss it if CD drops before we
	     * get to clear CLOCAL below.  On systems where we can talk
	     * successfully to the modem with CLOCAL clear and CD down,
	     * we could clear CLOCAL at this point.
	     */
	    set_up_tty(ttyfd, ((connector != NULL && connector[0] != 0)
			       || initializer != NULL));
	    real_ttyfd = ttyfd;
	}

	/* run connection script */
	if ((connector && connector[0]) || initializer) {
	    if (real_ttyfd != -1) {
		/* XXX do this if doing_callback == CALLBACK_DIALIN? */
		if (!default_device && modem) {
		    setdtr(real_ttyfd, 0);	/* in case modem is off hook */
		    sleep(1);
		    setdtr(real_ttyfd, 1);
		}
	    }

	    if (initializer && initializer[0]) {
		if (device_script(ttyfd, DIALER_INIT, initializer) < 0) {
		    error("Initializer script failed");
		    pppd_status = EXIT_INIT_FAILED;
		    goto fail;
		}
		if (pppd_kill_link)
		    goto disconnect;

		info("Serial port initialized.");
	    }

	    if (connector && connector[0]) {
		if (device_script(ttyfd, DIALER_CONNECT, connector) < 0) {
		    error("Connect script failed");
		    pppd_status = EXIT_CONNECT_FAILED;
		    goto fail;
		}
		if (pppd_kill_link)
		    goto disconnect;

		info("Serial connection established.");
	    }

	    /* set line speed, flow control, etc.;
	       clear CLOCAL if modem option */
	    if (real_ttyfd != -1)
		set_up_tty(real_ttyfd, 0);

	    if (doing_callback == CALLBACK_DIALIN)
		connector = NULL;
	}

	/* reopen tty if necessary to wait for carrier */
	if (connector == NULL && modem && devnam[0] != 0) {
	    for (;;) {
		if ((i = open(devnam, O_RDWR)) >= 0)
		    break;
		if (errno != EINTR) {
		    error("Failed to reopen %s: %m", devnam);
		    pppd_status = EXIT_OPEN_FAILED;
		}
		if (!persist || errno != EINTR || hungup || pppd_kill_link)
		    goto fail;
	    }
	    close(i);
	}

        info("Serial connection established.");
        sleep(1);

	/* run welcome script, if any */
	if (welcomer && welcomer[0]) {
	    if (device_script(ttyfd, DIALER_WELCOME, welcomer) < 0)
		warn("Welcome script failed");
	}

	/* set up the serial device as a ppp interface */
	fd_ppp = establish_ppp(ttyfd);
	if (fd_ppp < 0) {
	    pppd_status = EXIT_FATAL_ERROR;
	    goto disconnect;
	}

	if (!demand) {
	    info("Using interface ppp%d", pppifunit);
	    slprintf(ifname, sizeof(ifname), "ppp%d", pppifunit);
	}

	/*
	 * Start opening the connection and wait for
	 * incoming events (reply, timeout, etc.).
	 */
	notice("Connect: %s <--> %s", ifname, ppp_devnam);
	gettimeofday(&start_time, NULL);

	lcp_lowerup(0);
	lcp_open(0);		/* Start protocol */

	open_ccp_flag = 0;
	pppd_status = EXIT_NEGOTIATION_FAILED;
	new_phase(PHASE_ESTABLISH);
	while (pppd_phase != PHASE_DEAD) {
   	    wait_input(timeleft(&timo));
	    calltimeout();
            get_input();

	    if (pppd_kill_link) {
		lcp_close(0, "User request");
		pppd_kill_link = 0;
	    }
	    if (open_ccp_flag) {
		if (pppd_phase == PHASE_NETWORK || pppd_phase == PHASE_RUNNING) {
		    ccp_fsm[0].flags = OPT_RESTART; /* clears OPT_SILENT */
		    (*ccp_protent.open)(0);
		}
		open_ccp_flag = 0;
	    }
	}

	/*
	 * If we may want to bring the link up again, transfer
	 * the ppp unit back to the loopback.  Set the
	 * real serial device back to its normal mode of operation.
	 */
	clean_check();
	if (demand)
	    restore_loop();
	disestablish_ppp(ttyfd);
	fd_ppp = -1;
	if (!hungup)
	    lcp_lowerdown(0);

	/*
	 * Run disconnector script, if requested.
	 * XXX we may not be able to do this if the line has hung up!
	 */
    disconnect:
	if (disconnect_script && !hungup) {
	    new_phase(PHASE_DISCONNECT);
	    if (real_ttyfd >= 0)
		set_up_tty(real_ttyfd, 1);
	    if (device_script(ttyfd, DIALER_DISCONNECT, disconnect_script) < 0) {
		warn("disconnect script failed");
	    } else {
		info("Serial link disconnected.");
	    }
	}

    fail:
	if (pty_master >= 0)
	    close(pty_master);
	if (pty_slave >= 0)
	    close(pty_slave);
	if (real_ttyfd >= 0)
	    close_tty();

	if (!persist || (maxfail > 0 && unsuccess >= maxfail))
	    break;