vpncloud/src/tapdev.rs

50 lines
1.3 KiB
Rust

use std::fs;
use std::io::{Read, Write, Result as IoResult, Error as IoError};
use std::os::unix::io::AsRawFd;
use libc;
extern {
fn setup_tap_device(fd: i32, ifname: *mut u8) -> i32;
}
pub struct TapDevice {
fd: fs::File,
ifname: String
}
impl TapDevice {
pub fn new(ifname: &str) -> IoResult<TapDevice> {
let fd = try!(fs::OpenOptions::new().read(true).write(true).open("/dev/net/tun"));
let mut ifname_string = String::with_capacity(32);
ifname_string.push_str(ifname);
ifname_string.push('\0');
let mut ifname_c = ifname_string.into_bytes();
let mut res: i32;
unsafe {
res = setup_tap_device(fd.as_raw_fd(), ifname_c.as_mut_ptr());
if res == 0 {
res = libc::fcntl(fd.as_raw_fd(), libc::consts::os::posix01::F_SETFL, libc::consts::os::extra::O_NONBLOCK);
}
}
match res {
0 => Ok(TapDevice{fd: fd, ifname: String::from_utf8(ifname_c).unwrap()}),
_ => Err(IoError::last_os_error())
}
}
pub fn ifname(&self) -> &str {
&self.ifname
}
#[inline(always)]
pub fn read(&mut self, buffer: &mut [u8]) -> IoResult<usize> {
self.fd.read(buffer)
}
#[inline(always)]
pub fn write(&mut self, buffer: &[u8]) -> IoResult<()> {
self.fd.write_all(buffer)
}
}