minor link handling improvements

src/link.rs

@@ -1,4 +1,3 @@
-use crate::namespace::{NamespaceEnterError, NamespaceHandle};
 use neli::consts::nl::NlmF;
 use neli::consts::rtnl::Ifla;
 use neli::consts::rtnl::RtAddrFamily;
@@ -12,25 +11,28 @@ use neli::rtnl::{Ifinfomsg, RtattrBuilder};
 use neli::types::{Buffer, RtBuffer};
 use neli::utils::Groups;
 use nix::libc::c_int;
+use std::fmt::Debug;
 use std::os::fd::AsRawFd;
 use thiserror::Error;
 use tracing::info;
 
 #[derive(Debug, Error)]
 pub enum LinkError {
-    #[error("failed to communicate with netlink")]
-    Netlink,
-    #[error("failed to code netlink response")]
-    Parse,
+    #[error("Failed to communicate with netlink:")]
+    Netlink(String),
+    #[error("Failed to parse netlink response")]
+    Parse(String),
     #[error("Link not found: {0}")]
     NotFound(String),
-    #[error(transparent)]
-    Enter(#[from] NamespaceEnterError),
 }
 
-impl<T, P> From<RouterError<T, P>> for LinkError {
-    fn from(_value: RouterError<T, P>) -> Self {
-        LinkError::Netlink
+impl<T, P> From<RouterError<T, P>> for LinkError
+where
+    T: Debug,
+    P: Debug,
+{
+    fn from(value: RouterError<T, P>) -> Self {
+        LinkError::Netlink(value.to_string())
     }
 }
 
@@ -89,7 +91,7 @@ impl LinkManager {
                         .rtattrs()
                         .get_attr_handle()
                         .get_attr_payload_as_with_len::<String>(Ifla::Ifname)
-                        .map_err(|_| LinkError::Parse)?;
+                        .map_err(|e| LinkError::Parse(e.to_string()))?;
                     Ok(Some(Link {
                         family: *payload.ifi_family(),
                         index: *payload.ifi_index(),
@@ -103,7 +105,7 @@ impl LinkManager {
     }
 
     /// Move a link to a namespace
-    pub fn move_link<Fd: AsRawFd>(&self, link: &Link, namespace: Fd) -> Result<(), LinkError> {
+    pub fn move_link<Fd: AsRawFd>(&self, link: &Link, namespace: &Fd) -> Result<(), LinkError> {
         let ns_handle = namespace.as_raw_fd();
 
         let mut info_attrs = RtBuffer::<Ifla, Buffer>::new();
@@ -143,27 +145,21 @@ pub fn link_up(link_name: &str) -> Result<(), LinkError> {
 }
 
 /// Move a link into a namespace
-pub fn move_link_into(link_name: &str, namespace: &NamespaceHandle) -> Result<(), LinkError> {
+pub fn move_link_into<Fd: AsRawFd>(link_name: &str, namespace: &Fd) -> Result<(), LinkError> {
     let manager = LinkManager::new()?;
     let link = manager.get_link(link_name)?;
     info!(name = &link.name, "moving link into namespace");
     manager.move_link(&link, namespace)
 }
 
-/// Move all  links out of a namespace, except for lo
-pub fn move_all_links_out(
-    namespace: &NamespaceHandle,
-    parent: &NamespaceHandle,
-) -> Result<(), LinkError> {
-    namespace.run_in(|| {
-        let manager = LinkManager::new()?;
-        for link in manager.get_links()?.flatten() {
-            if link.name != "lo" {
-                info!(name = &link.name, "moving link out of namespace");
-                manager.move_link(&link, parent)?
-            }
+/// Move all links from the current namespace (except lo) into a namespace
+pub fn move_all_links<Fd: AsRawFd>(namespace: &Fd) -> Result<(), LinkError> {
+    let manager = LinkManager::new()?;
+    for link in manager.get_links()?.flatten() {
+        if link.name != "lo" {
+            info!(name = &link.name, "moving link");
+            manager.move_link(&link, namespace)?
         }
-        Ok::<_, LinkError>(())
-    })??;
-    Ok(())
+    }
+    Ok::<_, LinkError>(())
 }

src/namespace/mod.rs

@@ -2,7 +2,7 @@ mod handle;
 mod raw;
 
 use crate::config::{DeviceName, NamespaceName};
-use crate::link::{link_up, move_all_links_out, move_link_into, LinkError};
+use crate::link::{link_up, move_all_links, move_link_into, LinkError};
 pub use crate::namespace::handle::{NamespaceHandle, NamespaceHandleError};
 use crate::namespace::raw::{create_network_namespace, NamespaceSetupError};
 use either::Either;
@@ -162,7 +162,9 @@ impl NetNs {
     pub fn delete(self) -> Result<(), NamespaceError> {
         let parent_namespace = NamespaceHandle::parent()?;
 
-        move_all_links_out(self.handle(), &parent_namespace)?;
+        self.handle.run_in(|| {
+            move_all_links(&parent_namespace)
+        })??;
         let name = self.path.file_name().unwrap().to_str().unwrap();
         info!(name, "deleting network namespace");
         match umount2(&self.path, MntFlags::MNT_DETACH) {