mirror of https://github.com/aya-rs/aya
Add program::links() and NetworkInterface
NetworkInterface provides a way to store network interface indexes as well as retrieve an interface's name using the NetworkInterface.name() method. Interfaces can be created manually or retrieved via new .interface() methods on XdpLink and SchedClassifierLink. Interface names are extracted from the kernel for 2 reasons. 1. Interface names can change within the kernel at anytime which aya will not be aware of. 2. Names are not always available when a NetworkInterface is created. For example in the XdpLink .interface() implementation. A new method NetworkInterface::list() also provides a list of network interfaces from the kernel. Signed-off-by: Ayrton Sparling <ayrton@sparling.us>pull/478/head
Ayrton Sparling
3 years ago
parent
9f5d157628
commit
dc64377836
@ -0,0 +1,168 @@
|
||||
//! Network interfaces representing kernel network interfaces.
|
||||
|
||||
use std::ffi::CStr;
|
||||
|
||||
use libc::if_nameindex;
|
||||
|
||||
#[derive(Debug, Clone)]
|
||||
/// A kernel network interface.
|
||||
// if_name isn't stored because it can change in the kernel and aya won't know
|
||||
pub struct NetworkInterface {
|
||||
pub(crate) index: i32,
|
||||
}
|
||||
|
||||
impl NetworkInterface {
|
||||
/// Provides a number that can be used to identify this interface on this system.
|
||||
pub fn index(&self) -> i32 {
|
||||
self.index
|
||||
}
|
||||
|
||||
/// Extracts the interface name from the kernel.
|
||||
pub fn name(&self) -> Result<String, std::io::Error> {
|
||||
let mut buffer: [libc::c_char; libc::IF_NAMESIZE] = [0; libc::IF_NAMESIZE];
|
||||
let name = unsafe {
|
||||
// Returns null on error
|
||||
let res = libc::if_indextoname(self.index as u32, buffer.as_mut_ptr());
|
||||
|
||||
if res.is_null() {
|
||||
return Err(std::io::Error::last_os_error());
|
||||
}
|
||||
|
||||
CStr::from_ptr(buffer.as_ptr())
|
||||
};
|
||||
|
||||
Ok(name.to_string_lossy().to_string())
|
||||
}
|
||||
|
||||
/// Provides a [Vec] of all operating system network interfaces, including virtual ones.
|
||||
/// # Example
|
||||
///
|
||||
/// ```
|
||||
/// let interfaces_names: Vec<String> = NetworkInterface::list()
|
||||
/// .iter()
|
||||
/// .map(|interface| interface.name().unwrap())
|
||||
/// .collect();
|
||||
/// ```
|
||||
pub fn list() -> Vec<NetworkInterface> {
|
||||
let mut list = Vec::new();
|
||||
|
||||
// The nameindex array is terminated by an interface with if_index == 0 and if_name == null
|
||||
let head = unsafe { libc::if_nameindex() };
|
||||
let mut curr = head;
|
||||
|
||||
while let Ok(interface) = NetworkInterface::try_from(unsafe { *curr }) {
|
||||
list.push(interface);
|
||||
curr = unsafe { curr.add(1) };
|
||||
}
|
||||
|
||||
unsafe {
|
||||
libc::if_freenameindex(head);
|
||||
};
|
||||
|
||||
list
|
||||
}
|
||||
}
|
||||
|
||||
impl TryFrom<if_nameindex> for NetworkInterface {
|
||||
type Error = ();
|
||||
|
||||
// Returns Err is the interface is invalid (zeroed)
|
||||
fn try_from(value: if_nameindex) -> Result<Self, ()> {
|
||||
if value.if_index == 0 || value.if_name.is_null() {
|
||||
return Err(());
|
||||
}
|
||||
|
||||
Ok(NetworkInterface {
|
||||
index: value.if_index as i32,
|
||||
})
|
||||
}
|
||||
}
|
||||
|
||||
#[cfg(test)]
|
||||
mod tests {
|
||||
use std::ffi::CString;
|
||||
|
||||
use crate::interface::NetworkInterface;
|
||||
|
||||
#[test]
|
||||
fn network_interface_list() {
|
||||
let interfaces_dir = "/sys/class/net";
|
||||
|
||||
let expected: Vec<String> = std::fs::read_dir(interfaces_dir)
|
||||
.unwrap()
|
||||
.map(|entry| entry.unwrap().file_name().into_string().unwrap())
|
||||
.collect();
|
||||
|
||||
let interfaces = NetworkInterface::list();
|
||||
|
||||
assert_eq!(expected.len(), interfaces.len());
|
||||
|
||||
for interface in interfaces {
|
||||
let name = interface.name().unwrap().to_string();
|
||||
assert!(expected.contains(&name));
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn network_interface_try_from() {
|
||||
use libc::if_nameindex;
|
||||
use std::ptr::null_mut;
|
||||
|
||||
let name = CString::new("eth0").unwrap();
|
||||
|
||||
let k_interface = if_nameindex {
|
||||
if_index: 1,
|
||||
if_name: name.as_ptr() as *mut i8,
|
||||
};
|
||||
|
||||
let interface = NetworkInterface::try_from(k_interface).unwrap();
|
||||
|
||||
assert_eq!(interface.index(), 1);
|
||||
|
||||
let invalid_k_interface = if_nameindex {
|
||||
if_index: 0,
|
||||
if_name: null_mut(),
|
||||
};
|
||||
|
||||
let res = NetworkInterface::try_from(invalid_k_interface);
|
||||
assert_eq!(res.unwrap_err(), ());
|
||||
|
||||
let invalid_k_interface = if_nameindex {
|
||||
if_index: 1,
|
||||
if_name: null_mut(),
|
||||
};
|
||||
|
||||
let res = NetworkInterface::try_from(invalid_k_interface);
|
||||
assert_eq!(res.unwrap_err(), ());
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn network_interface_name() {
|
||||
let interfaces_dir = "/sys/class/net";
|
||||
|
||||
let first_interface_path = std::fs::read_dir(interfaces_dir)
|
||||
.expect("Failed to read sysfs interface directory")
|
||||
.next();
|
||||
|
||||
if let Some(first_interface_path) = first_interface_path {
|
||||
let (name, index) = {
|
||||
let entry = first_interface_path.unwrap();
|
||||
let file_name = entry.file_name();
|
||||
let mut path = entry.path();
|
||||
path.push("ifindex");
|
||||
let index_contents = String::from_utf8(std::fs::read(path).unwrap()).unwrap();
|
||||
let index = index_contents.trim().parse::<i32>().unwrap();
|
||||
(file_name, index)
|
||||
};
|
||||
|
||||
let interface = NetworkInterface { index };
|
||||
|
||||
assert_eq!(
|
||||
name.to_string_lossy().to_string(),
|
||||
interface.name().unwrap()
|
||||
);
|
||||
} else {
|
||||
panic!("no interfaces found in {interfaces_dir} to test");
|
||||
}
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue