burrow/tun/src/unix/apple/kern_control.rs
Conrad Kramer 1a13b77295 wip
2023-04-22 12:02:57 -04:00

56 lines
1.6 KiB
Rust

use fehler::throws;
use libc::{sockaddr_ctl, AF_SYSTEM, AF_SYS_CONTROL};
use std::io::Error;
use std::mem::size_of;
use std::os::unix::io::AsRawFd;
/// Trait to connect to kernel extensions on Apple platforms
///
/// Pulled from XNU source: https://github.com/apple/darwin-xnu/blob/main/bsd/sys/kern_control.h
pub trait SysControlSocket {
#[throws]
fn resolve(&self, name: &str, index: u32) -> socket2::SockAddr;
}
impl SysControlSocket for socket2::Socket {
#[throws]
fn resolve(&self, name: &str, index: u32) -> socket2::SockAddr {
let mut info = sys::ctl_info {
ctl_id: 0,
ctl_name: [0; 96],
};
info.ctl_name[..name.len()].copy_from_slice(name.as_bytes());
unsafe { sys::resolve_ctl_info(self.as_raw_fd(), &mut info as *mut sys::ctl_info)? };
let (_, addr) = unsafe {
socket2::SockAddr::init(|addr_storage, len| {
*len = size_of::<sockaddr_ctl>() as u32;
let mut addr: &mut sockaddr_ctl = &mut *addr_storage.cast();
addr.sc_len = *len as u8;
addr.sc_family = AF_SYSTEM as u8;
addr.ss_sysaddr = AF_SYS_CONTROL as u16;
addr.sc_id = info.ctl_id;
addr.sc_unit = index;
Ok(())
})
}?;
addr
}
}
mod sys {
use nix::ioctl_readwrite;
const MAX_KCTL_NAME: usize = 96;
#[repr(C)]
pub struct ctl_info {
pub ctl_id: u32,
pub ctl_name: [u8; MAX_KCTL_NAME],
}
ioctl_readwrite!(resolve_ctl_info, b'N', 3, ctl_info);
}