sys-sunos4.c

经典的ppp程序

/*
 * System-dependent procedures for pppd under SunOS 4.
 *
 * Copyright (c) 1994 The Australian National University.
 * All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software and its
 * documentation is hereby granted, provided that the above copyright
 * notice appears in all copies.  This software is provided without any
 * warranty, express or implied. The Australian National University
 * makes no representations about the suitability of this software for
 * any purpose.
 *
 * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
 * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
 * THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
 * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
 * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
 * OR MODIFICATIONS.
 */

#define RCSID	"$Id: sys-sunos4.c,v 1.26 2001/03/12 22:59:00 paulus Exp $"

#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <termios.h>
#include <signal.h>
#include <malloc.h>
#include <utmp.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/stream.h>
#include <sys/stropts.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/poll.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <net/nit_if.h>
#include <net/route.h>
#include <net/ppp_defs.h>
#include <net/pppio.h>
#include <netinet/in.h>

#include "pppd.h"

#if defined(sun) && defined(sparc)
#include <alloca.h>
#ifndef __GNUC__
extern void *alloca();
#endif
#endif /*sparc*/

static const char rcsid[] = RCSID;

static int	pppfd;
static int	fdmuxid = -1;
static int	iffd;
static int	sockfd;

static int	restore_term;
static struct termios inittermios;
static struct winsize wsinfo;	/* Initial window size info */
static pid_t	parent_pid;	/* PID of our parent */

extern u_char	inpacket_buf[];	/* borrowed from main.c */

#define MAX_POLLFDS	32
static struct pollfd pollfds[MAX_POLLFDS];
static int n_pollfds;

static int	link_mtu, link_mru;

#define NMODULES	32
static int	tty_nmodules;
static char	tty_modules[NMODULES][FMNAMESZ+1];

static int	if_is_up;	/* Interface has been marked up */
static u_int32_t ifaddrs[2];	/* local and remote addresses */
static u_int32_t default_route_gateway;	/* Gateway for default route added */
static u_int32_t proxy_arp_addr;	/* Addr for proxy arp entry added */

/* Prototypes for procedures local to this file. */
static int translate_speed __P((int));
static int baud_rate_of __P((int));
static int get_ether_addr __P((u_int32_t, struct sockaddr *));
static int strioctl __P((int, int, void *, int, int));


/*
 * sys_init - System-dependent initialization.
 */
void
sys_init()
{
    int x;

    /* Get an internet socket for doing socket ioctl's on. */
    if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
	fatal("Couldn't create IP socket: %m");

    /*
     * We may want to send a SIGHUP to the session leader associated
     * with our controlling terminal later.  Because SunOS doesn't
     * have getsid(), we make do with sending the signal to our
     * parent process.
     */
    parent_pid = getppid();

    /*
     * Open the ppp device.
     */
    pppfd = open("/dev/ppp", O_RDWR | O_NONBLOCK, 0);
    if (pppfd < 0)
	fatal("Can't open /dev/ppp: %m");
    if (kdebugflag) {
	x = PPPDBG_LOG + PPPDBG_DRIVER;
	strioctl(pppfd, PPPIO_DEBUG, &x, sizeof(int), 0);
    }

    /* Assign a new PPA and get its unit number. */
    if (strioctl(pppfd, PPPIO_NEWPPA, &ifunit, 0, sizeof(int)) < 0)
	fatal("Can't create new PPP interface: %m");

    /*
     * Open the ppp device again and push the if_ppp module on it.
     */
    iffd = open("/dev/ppp", O_RDWR, 0);
    if (iffd < 0)
	fatal("Can't open /dev/ppp (2): %m");
    if (kdebugflag) {
	x = PPPDBG_LOG + PPPDBG_DRIVER;
	strioctl(iffd, PPPIO_DEBUG, &x, sizeof(int), 0);
    }
    if (strioctl(iffd, PPPIO_ATTACH, &ifunit, sizeof(int), 0) < 0)
	fatal("Couldn't attach ppp interface to device: %m");
    if (ioctl(iffd, I_PUSH, "if_ppp") < 0)
	fatal("Can't push ppp interface module: %m");
    if (kdebugflag) {
	x = PPPDBG_LOG + PPPDBG_IF;
	strioctl(iffd, PPPIO_DEBUG, &x, sizeof(int), 0);
    }
    if (strioctl(iffd, PPPIO_NEWPPA, &ifunit, sizeof(int), 0) < 0)
	fatal("Couldn't create ppp interface unit: %m");
    x = PPP_IP;
    if (strioctl(iffd, PPPIO_BIND, &x, sizeof(int), 0) < 0)
	fatal("Couldn't bind ppp interface to IP SAP: %m");

    n_pollfds = 0;
}

/*
 * sys_cleanup - restore any system state we modified before exiting:
 * mark the interface down, delete default route and/or proxy arp entry.
 * This shouldn't call die() because it's called from die().
 */
void
sys_cleanup()
{
    if (if_is_up)
	sifdown(0);
    if (ifaddrs[0])
	cifaddr(0, ifaddrs[0], ifaddrs[1]);
    if (default_route_gateway)
	cifdefaultroute(0, 0, default_route_gateway);
    if (proxy_arp_addr)
	cifproxyarp(0, proxy_arp_addr);
}

/*
 * sys_close - Clean up in a child process before execing.
 */
void
sys_close()
{
    close(iffd);
    close(pppfd);
    close(sockfd);
}

/*
 * sys_check_options - check the options that the user specified
 */
int
sys_check_options()
{
    return 1;
}

#if 0
/*
 * daemon - Detach us from controlling terminal session.
 */
int
daemon(nochdir, noclose)
    int nochdir, noclose;
{
    int pid;

    if ((pid = fork()) < 0)
	return -1;
    if (pid != 0)
	exit(0);		/* parent dies */
    setsid();
    if (!nochdir)
	chdir("/");
    if (!noclose) {
	fclose(stdin);		/* don't need stdin, stdout, stderr */
	fclose(stdout);
	fclose(stderr);
    }
    return 0;
}
#endif

/*
 * ppp_available - check whether the system has any ppp interfaces
 */
int
ppp_available()
{
    struct stat buf;

    return stat("/dev/ppp", &buf) >= 0;
}

/*
 * tty_establish_ppp - Turn the serial port into a ppp interface.
 */
int
tty_establish_ppp(fd)
    int fd;
{
    int i;

    /* Pop any existing modules off the tty stream. */
    for (i = 0;; ++i)
	if (ioctl(fd, I_LOOK, tty_modules[i]) < 0
	    || ioctl(fd, I_POP, 0) < 0)
	    break;
    tty_nmodules = i;

    /* Push the async hdlc module and the compressor module. */
    if (ioctl(fd, I_PUSH, "ppp_ahdl") < 0)
	fatal("Couldn't push PPP Async HDLC module: %m");
    if (ioctl(fd, I_PUSH, "ppp_comp") < 0)
	error("Couldn't push PPP compression module: %m");

    /* Link the serial port under the PPP multiplexor. */
    if ((fdmuxid = ioctl(pppfd, I_LINK, fd)) < 0)
	fatal("Can't link tty to PPP mux: %m");

    return pppfd;
}

/*
 * disestablish_ppp - Restore the serial port to normal operation.
 * It attempts to reconstruct the stream with the previously popped
 * modules.  This shouldn't call die() because it's called from die().
 */
void
tty_disestablish_ppp(fd)
    int fd;
{
    int i;

    if (fdmuxid >= 0) {
	if (ioctl(pppfd, I_UNLINK, fdmuxid) < 0) {
	    if (!hungup)
		error("Can't unlink tty from PPP mux: %m");
	}
	fdmuxid = -1;

	if (!hungup) {
	    while (ioctl(fd, I_POP, 0) >= 0)
		;
	    for (i = tty_nmodules - 1; i >= 0; --i)
		if (ioctl(fd, I_PUSH, tty_modules[i]) < 0)
		    error("Couldn't restore tty module %s: %m",
			   tty_modules[i]);
	}
	if (hungup && default_device && parent_pid > 0) {
	    /*
	     * If we have received a hangup, we need to send a SIGHUP
	     * to the terminal's controlling process.  The reason is
	     * that the original stream head for the terminal hasn't
	     * seen the M_HANGUP message (it went up through the ppp
	     * driver to the stream head for our fd to /dev/ppp).
	     * Actually we send the signal to the process that invoked
	     * pppd, since SunOS doesn't have getsid().
	     */
	    kill(parent_pid, SIGHUP);
	}
    }
}

/*
 * Check whether the link seems not to be 8-bit clean.
 */
void
clean_check()
{
    int x;
    char *s;

    if (strioctl(pppfd, PPPIO_GCLEAN, &x, 0, sizeof(x)) < 0)
	return;
    s = NULL;
    switch (~x) {
    case RCV_B7_0:
	s = "bit 7 set to 1";
	break;
    case RCV_B7_1:
	s = "bit 7 set to 0";
	break;
    case RCV_EVNP:
	s = "odd parity";
	break;
    case RCV_ODDP:
	s = "even parity";
	break;
    }
    if (s != NULL) {
	warn("Serial link is not 8-bit clean:");
	warn("All received characters had %s", s);
    }
}

/*
 * 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.
 */
static 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;
    warn("speed %d not supported", bps);
    return 0;
}

/*
 * Translate from a speed_t to bits/second.
 */
static 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;
}

/*
 * 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.
 */
void
set_up_tty(fd, local)
    int fd, local;
{
    int speed;
    struct termios tios;

    if (tcgetattr(fd, &tios) < 0)
	fatal("tcgetattr: %m");

    if (!restore_term) {
	inittermios = tios;
	ioctl(fd, TIOCGWINSZ, &wsinfo);
    }

    tios.c_cflag &= ~(CSIZE | CSTOPB | PARENB | CLOCAL);
    if (crtscts > 0)
	tios.c_cflag |= CRTSCTS;
    else if (crtscts < 0)
	tios.c_cflag &= ~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 |= IXON | 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);
	/*
	 * We can't proceed if the serial port speed is 0,
	 * since that implies that the serial port is disabled.
	 */
	if (speed == B0)
	    fatal("Baud rate for %s is 0; need explicit baud rate", devnam);
    }

    if (tcsetattr(fd, TCSAFLUSH, &tios) < 0)
	fatal("tcsetattr: %m");

    baud_rate = inspeed = baud_rate_of(speed);
    restore_term = 1;
}

/*
 * restore_tty - restore the terminal to the saved settings.
 */
void
restore_tty(fd)
    int fd;