feat(rosenpass): Add wireguard-broker interface in AppServer (#303)

Dynamically dispatch WireguardBrokerMio trait in AppServer. Also allows for mio event registration and poll processing, logic from dev/broker-architecture branch

Co-authored-by: Prabhpreet Dua <615318+prabhpreet@users.noreply.github.com>
Co-authored-by: Karolin Varner <karo@cupdev.net>

rosenpass/tests/integration_test.rs

@@ -1,7 +1,15 @@
-use std::{fs, net::UdpSocket, path::PathBuf, time::Duration};
+use std::{
+    fs,
+    net::UdpSocket,
+    path::PathBuf,
+    sync::{Arc, Mutex},
+    time::Duration,
+};
 
-use clap::Parser;
+use clap::{builder::Str, Parser};
 use rosenpass::{app_server::AppServerTestBuilder, cli::CliArgs};
+use rosenpass_secret_memory::{Public, Secret};
+use rosenpass_wireguard_broker::{WireguardBrokerMio, WG_KEY_LEN, WG_PEER_LEN};
 use serial_test::serial;
 use std::io::Write;
 
@@ -34,12 +42,7 @@ fn generate_keys() {
 }
 
 fn find_udp_socket() -> Option<u16> {
-    for port in 1025..=u16::MAX {
-        if UdpSocket::bind(("::1", port)).is_ok() {
-            return Some(port);
-        }
-    }
-    None
+    (1025..=u16::MAX).find(|&port| UdpSocket::bind(("::1", port)).is_ok())
 }
 
 fn setup_logging() {
@@ -271,3 +274,57 @@ fn check_exchange_under_dos() {
     // cleanup
     fs::remove_dir_all(&tmpdir).unwrap();
 }
+
+#[derive(Debug, Default)]
+struct MockBrokerInner {
+    psk: Option<Secret<WG_KEY_LEN>>,
+    peer_id: Option<Public<WG_PEER_LEN>>,
+    interface: Option<String>,
+}
+
+#[derive(Debug, Default)]
+struct MockBroker {
+    inner: Arc<Mutex<MockBrokerInner>>,
+}
+
+impl WireguardBrokerMio for MockBroker {
+    type MioError = anyhow::Error;
+
+    fn register(
+        &mut self,
+        _registry: &mio::Registry,
+        _token: mio::Token,
+    ) -> Result<(), Self::MioError> {
+        Ok(())
+    }
+
+    fn process_poll(&mut self) -> Result<(), Self::MioError> {
+        Ok(())
+    }
+
+    fn unregister(&mut self, _registry: &mio::Registry) -> Result<(), Self::MioError> {
+        Ok(())
+    }
+}
+
+impl rosenpass_wireguard_broker::WireGuardBroker for MockBroker {
+    type Error = anyhow::Error;
+
+    fn set_psk(
+        &mut self,
+        config: rosenpass_wireguard_broker::SerializedBrokerConfig<'_>,
+    ) -> Result<(), Self::Error> {
+        loop {
+            let mut lock = self.inner.try_lock();
+
+            if let Ok(ref mut mutex) = lock {
+                **mutex = MockBrokerInner {
+                    psk: Some(config.psk.clone()),
+                    peer_id: Some(config.peer_id.clone()),
+                    interface: Some(std::str::from_utf8(config.interface).unwrap().to_string()),
+                };
+                break Ok(());
+            }
+        }
+    }
+}