hypha: protect from panics in the network stack (due to interface going away)

hypha/src/network/mod.rs

@@ -1,7 +1,8 @@
 use std::os::fd::AsRawFd;
+use std::panic::UnwindSafe;
 use std::str::FromStr;
-use std::thread;
 use std::time::Duration;
+use std::{panic, thread};
 
 use advmac::MacAddr6;
 use anyhow::{anyhow, Result};
@@ -21,6 +22,7 @@ pub struct NetworkBackend {
 }
 
 unsafe impl Send for NetworkBackend {}
+impl UnwindSafe for NetworkBackend {}
 
 pub struct NetworkService {
     pub network: String,
@@ -66,10 +68,25 @@ impl NetworkBackend {
         }
         let link = link.unwrap();
         handle.link().set(link.header.index).up().execute().await?;
+        tokio::time::sleep(Duration::from_secs(3)).await;
         Ok(())
     }
 
-    pub fn run(&mut self) -> Result<()> {
+    pub fn run(mut self) -> Result<()> {
+        let interface = self.interface.clone();
+        let result = panic::catch_unwind(move || self.run_maybe_panic());
+
+        if result.is_err() {
+            return Err(anyhow!(
+                "network backend for interface {} encountered an error and is now shutdown",
+                interface
+            ));
+        }
+
+        result.unwrap()
+    }
+
+    fn run_maybe_panic(&mut self) -> Result<()> {
         let mac = MacAddr6::random();
         let mac = HardwareAddress::Ethernet(EthernetAddress(mac.to_array()));
         let config = Config::new(mac);
@@ -128,14 +145,16 @@ impl NetworkService {
                 spawned.push(name);
             }
 
-            sleep(Duration::from_secs(5)).await;
+            sleep(Duration::from_secs(2)).await;
         }
     }
 
     async fn add_network_backend(&mut self, interface: &str) -> Result<()> {
         let interface = interface.to_string();
         let mut network = NetworkBackend::new(&interface, &[&self.network])?;
+        info!("initializing network backend for interface {}", interface);
         network.init().await?;
+        tokio::time::sleep(Duration::from_secs(1)).await;
         info!("spawning network backend for interface {}", interface);
         thread::spawn(move || {
             if let Err(error) = network.run() {