text: /*  
      VTun - Virtual Tunnel over TCP/IP network.
  
      Copyright (C) 1998-2000  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.
   */
  
  /*
   * tun_dev.c,v 1.2.2.1.2.1 2006/11/16 04:04:40 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 ) {
         sprintf(tunname, "/dev/%s", dev);
         return open(tunname, O_RDWR);
      }
  
      for(i=0; i < 255; i++){
         sprintf(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);
  }
  