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/*
* $Id$
*
* Get the device used for the tunnel in a portable way
*
*/
#ifdef LINUX
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/sysmacros.h>
#include <fcntl.h>
#include <unistd.h>
#endif /* LINUX */
#include <stdio.h>
#include <stdlib.h>
#include <syslog.h>
#include "device.h"
#define MODULE_NAME "userlink"
#define DEVICES_FILE "/proc/devices"
#define INSMOD_COMMAND "/sbin/insmod -k %s"
#define RMMOD_COMMAND "/sbin/rmmod %s"
#define BSD_NAME "/dev/tun%d"
#ifdef USE_LINUX_TUNTAP
#define LINUX_NAME "/dev/net/tun"
#else
#define LINUX_NAME "/dev/ul%d"
#endif
#ifdef LINUX
static struct device {
int minor;
char *name;
struct device *next;
} *devhead;
static int get_major_from_devices (void);
static int get_major (void);
static int
get_major_from_devices ()
{
FILE *dev;
char devname[128];
int major;
dev = fopen (DEVICES_FILE, "r");
while (!feof (dev)) {
if (fscanf (dev, "%d %s", &major, devname) == 2) {
if (strcmp (devname, MODULE_NAME) == 0) {
syslog (LOG_INFO, "major for module %s is %d", MODULE_NAME, major);
return major;
}
} else {
fgets (devname, sizeof devname, dev);
}
}
fclose (dev);
return -1;
}
static int
get_major ()
{
char command [1024];
int major;
major = get_major_from_devices ();
if (major == -1) {
syslog (LOG_NOTICE, "loading userlink module");
sprintf (command, INSMOD_COMMAND, MODULE_NAME);
system (command);
major = get_major_from_devices ();
}
if (major == -1) syslog (LOG_ALERT, "unable to find major for module %s",
MODULE_NAME);
return major;
}
#endif /* LINUX */
char *
get_device (int minor)
{
char buffer[256];
char *devname;
#ifdef LINUX
#ifdef USE_LINUX_TUNTAP
return LINUX_NAME;
#else
struct device *current;
int major;
for (current = devhead; current; current = current->next)
if (current->minor == minor) return current->name;
major = get_major ();
if (major == -1)
return NULL;
sprintf (buffer, LINUX_NAME, minor);
unlink (buffer);
if (mknod (buffer, S_IFCHR | 0600, makedev (major, minor)) != 0)
return NULL;
#endif
#else
sprintf (buffer, BSD_NAME, minor);
#endif
devname = malloc (strlen (buffer));
strcpy (devname, buffer);
#ifdef LINUX
#ifndef USE_LINUX_TUNTAP
current = (struct device *) malloc (sizeof (struct device));
current->minor = minor;
current->name = devname;
current->next = devhead;
devhead = current;
#endif
#endif
return devname;
}
char *
get_full_device (char *name)
{
char *current;
for (current = name; *current; current++) {
if (*current < '0' || *current > '9') return name;
}
return get_device (atoi (name));
}
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