vtun/generic/tun_dev.c

75 lines
1.7 KiB
C

/*
VTun - Virtual Tunnel over TCP/IP network.
Copyright (C) 1998-2008 Maxim Krasnyansky <max_mk@yahoo.com>
VTun has been derived from VPPP package by Maxim Krasnyansky.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
*/
/*
* $Id: tun_dev.c,v 1.5.2.2 2008/01/07 22:36:18 mtbishop Exp $
*/
#include "config.h"
#include <unistd.h>
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <syslog.h>
#include "vtun.h"
#include "lib.h"
/*
* Allocate TUN device, returns opened fd.
* Stores dev name in the first arg(must be large enough).
*/
int tun_open(char *dev)
{
char tunname[14];
int i, fd;
if( *dev ) {
snprintf(tunname, sizeof tunname, "/dev/%s", dev);
return open(tunname, O_RDWR);
}
for(i=0; i < 255; i++){
snprintf(tunname, sizeof tunname, "/dev/tun%d", i);
/* Open device */
if( (fd=open(tunname, O_RDWR)) > 0 ){
sprintf(dev, "tun%d", i);
return fd;
}
}
return -1;
}
int tun_close(int fd, char *dev)
{
return close(fd);
}
/* Read/write frames from TUN device */
int tun_write(int fd, char *buf, int len)
{
return write(fd, buf, len);
}
int tun_read(int fd, char *buf, int len)
{
return read(fd, buf, len);
}