Implement IP sink interface

src/ip_sink.rs

@@ -0,0 +1,35 @@
+use crate::virtual_device::VirtualIpDevice;
+use crate::wg::WireGuardTunnel;
+use smoltcp::iface::InterfaceBuilder;
+use smoltcp::socket::SocketSet;
+use std::sync::Arc;
+use tokio::time::Duration;
+
+/// A repeating task that processes unroutable IP packets.
+pub async fn run_ip_sink_interface(wg: Arc<WireGuardTunnel>) -> ! {
+    // Initialize interface
+    let device = VirtualIpDevice::new_sink(wg)
+        .await
+        .expect("Failed to initialize VirtualIpDevice for sink interface");
+
+    // No sockets on sink interface
+    let mut socket_set_entries: [_; 0] = Default::default();
+    let mut socket_set = SocketSet::new(&mut socket_set_entries[..]);
+    let mut virtual_interface = InterfaceBuilder::new(device).ip_addrs([]).finalize();
+
+    loop {
+        let loop_start = smoltcp::time::Instant::now();
+        match virtual_interface.poll(&mut socket_set, loop_start) {
+            Ok(processed) if processed => {
+                trace!("[SINK] Virtual interface polled some packets to be processed",);
+                tokio::time::sleep(Duration::from_millis(1)).await;
+            }
+            Err(e) => {
+                error!("[SINK] Virtual interface poll error: {:?}", e);
+            }
+            _ => {
+                tokio::time::sleep(Duration::from_millis(5)).await;
+            }
+        }
+    }
+}