Allow onetun to be used as a library

src/config.rs

@@ -12,19 +12,19 @@ const DEFAULT_PORT_FORWARD_SOURCE: &str = "127.0.0.1";
 
 #[derive(Clone, Debug)]
 pub struct Config {
-    pub(crate) port_forwards: Vec<PortForwardConfig>,
+    pub port_forwards: Vec<PortForwardConfig>,
     #[allow(dead_code)]
-    pub(crate) remote_port_forwards: Vec<PortForwardConfig>,
-    pub(crate) private_key: Arc<X25519SecretKey>,
-    pub(crate) endpoint_public_key: Arc<X25519PublicKey>,
-    pub(crate) endpoint_addr: SocketAddr,
-    pub(crate) endpoint_bind_addr: SocketAddr,
-    pub(crate) source_peer_ip: IpAddr,
-    pub(crate) keepalive_seconds: Option<u16>,
-    pub(crate) max_transmission_unit: usize,
-    pub(crate) log: String,
-    pub(crate) warnings: Vec<String>,
-    pub(crate) pcap_file: Option<String>,
+    pub remote_port_forwards: Vec<PortForwardConfig>,
+    pub private_key: Arc<X25519SecretKey>,
+    pub endpoint_public_key: Arc<X25519PublicKey>,
+    pub endpoint_addr: SocketAddr,
+    pub endpoint_bind_addr: SocketAddr,
+    pub source_peer_ip: IpAddr,
+    pub keepalive_seconds: Option<u16>,
+    pub max_transmission_unit: usize,
+    pub log: String,
+    pub warnings: Vec<String>,
+    pub pcap_file: Option<String>,
 }
 
 impl Config {

src/lib.rs

@@ -0,0 +1,122 @@
+#[macro_use]
+extern crate log;
+
+use std::sync::Arc;
+
+use anyhow::Context;
+
+use crate::config::{Config, PortProtocol};
+use crate::events::Bus;
+use crate::tunnel::tcp::TcpPortPool;
+use crate::tunnel::udp::UdpPortPool;
+use crate::virtual_device::VirtualIpDevice;
+use crate::virtual_iface::tcp::TcpVirtualInterface;
+use crate::virtual_iface::udp::UdpVirtualInterface;
+use crate::virtual_iface::VirtualInterfacePoll;
+use crate::wg::WireGuardTunnel;
+
+pub mod config;
+pub mod events;
+#[cfg(feature = "pcap")]
+pub mod pcap;
+pub mod tunnel;
+pub mod virtual_device;
+pub mod virtual_iface;
+pub mod wg;
+
+/// Starts the onetun tunnels in separate tokio tasks.
+///
+/// Note: This future completes immediately.
+pub async fn start_tunnels(config: Config, bus: Bus) -> anyhow::Result<()> {
+    // Initialize the port pool for each protocol
+    let tcp_port_pool = TcpPortPool::new();
+    let udp_port_pool = UdpPortPool::new();
+
+    #[cfg(feature = "pcap")]
+    if let Some(pcap_file) = config.pcap_file.clone() {
+        // Start packet capture
+        let bus = bus.clone();
+        tokio::spawn(async move { pcap::capture(pcap_file, bus).await });
+    }
+
+    let wg = WireGuardTunnel::new(&config, bus.clone())
+        .await
+        .with_context(|| "Failed to initialize WireGuard tunnel")?;
+    let wg = Arc::new(wg);
+
+    {
+        // Start routine task for WireGuard
+        let wg = wg.clone();
+        tokio::spawn(async move { wg.routine_task().await });
+    }
+
+    {
+        // Start consumption task for WireGuard
+        let wg = wg.clone();
+        tokio::spawn(async move { wg.consume_task().await });
+    }
+
+    {
+        // Start production task for WireGuard
+        let wg = wg.clone();
+        tokio::spawn(async move { wg.produce_task().await });
+    }
+
+    if config
+        .port_forwards
+        .iter()
+        .any(|pf| pf.protocol == PortProtocol::Tcp)
+    {
+        // TCP device
+        let bus = bus.clone();
+        let device =
+            VirtualIpDevice::new(PortProtocol::Tcp, bus.clone(), config.max_transmission_unit);
+
+        // Start TCP Virtual Interface
+        let port_forwards = config.port_forwards.clone();
+        let iface = TcpVirtualInterface::new(port_forwards, bus, config.source_peer_ip);
+        tokio::spawn(async move { iface.poll_loop(device).await });
+    }
+
+    if config
+        .port_forwards
+        .iter()
+        .any(|pf| pf.protocol == PortProtocol::Udp)
+    {
+        // UDP device
+        let bus = bus.clone();
+        let device =
+            VirtualIpDevice::new(PortProtocol::Udp, bus.clone(), config.max_transmission_unit);
+
+        // Start UDP Virtual Interface
+        let port_forwards = config.port_forwards.clone();
+        let iface = UdpVirtualInterface::new(port_forwards, bus, config.source_peer_ip);
+        tokio::spawn(async move { iface.poll_loop(device).await });
+    }
+
+    {
+        let port_forwards = config.port_forwards;
+        let source_peer_ip = config.source_peer_ip;
+
+        port_forwards
+            .into_iter()
+            .map(|pf| {
+                (
+                    pf,
+                    wg.clone(),
+                    tcp_port_pool.clone(),
+                    udp_port_pool.clone(),
+                    bus.clone(),
+                )
+            })
+            .for_each(move |(pf, wg, tcp_port_pool, udp_port_pool, bus)| {
+                tokio::spawn(async move {
+                    tunnel::port_forward(pf, source_peer_ip, tcp_port_pool, udp_port_pool, wg, bus)
+                        .await
+                        .unwrap_or_else(|e| error!("Port-forward failed for {} : {}", pf, e))
+                });
+            });
+    }
+
+    Ok(())
+}

src/main.rs

@@ -1,32 +1,13 @@
+#[cfg(feature = "bin")]
 #[macro_use]
 extern crate log;
 
-use std::sync::Arc;
-
-use anyhow::Context;
-
-use crate::config::{Config, PortProtocol};
-use crate::events::Bus;
-use crate::tunnel::tcp::TcpPortPool;
-use crate::tunnel::udp::UdpPortPool;
-use crate::virtual_device::VirtualIpDevice;
-use crate::virtual_iface::tcp::TcpVirtualInterface;
-use crate::virtual_iface::udp::UdpVirtualInterface;
-use crate::virtual_iface::VirtualInterfacePoll;
-use crate::wg::WireGuardTunnel;
-
-pub mod config;
-pub mod events;
-#[cfg(feature = "pcap")]
-pub mod pcap;
-pub mod tunnel;
-pub mod virtual_device;
-pub mod virtual_iface;
-pub mod wg;
-
 #[cfg(feature = "bin")]
 #[tokio::main]
 async fn main() -> anyhow::Result<()> {
+    use anyhow::Context;
+    use onetun::{config::Config, events::Bus};
+
     let config = Config::from_args().with_context(|| "Failed to read config")?;
     init_logger(&config)?;
 
@@ -34,102 +15,21 @@ async fn main() -> anyhow::Result<()> {
         warn!("{}", warning);
     }
 
-    // Initialize the port pool for each protocol
-    let tcp_port_pool = TcpPortPool::new();
-    let udp_port_pool = UdpPortPool::new();
-
     let bus = Bus::default();
-
-    if let Some(pcap_file) = config.pcap_file.clone() {
-        // Start packet capture
-        let bus = bus.clone();
-        tokio::spawn(async move { pcap::capture(pcap_file, bus).await });
-    }
-
-    let wg = WireGuardTunnel::new(&config, bus.clone())
-        .await
-        .with_context(|| "Failed to initialize WireGuard tunnel")?;
-    let wg = Arc::new(wg);
-
-    {
-        // Start routine task for WireGuard
-        let wg = wg.clone();
-        tokio::spawn(async move { wg.routine_task().await });
-    }
-
-    {
-        // Start consumption task for WireGuard
-        let wg = wg.clone();
-        tokio::spawn(async move { wg.consume_task().await });
-    }
-
-    {
-        // Start production task for WireGuard
-        let wg = wg.clone();
-        tokio::spawn(async move { wg.produce_task().await });
-    }
-
-    if config
-        .port_forwards
-        .iter()
-        .any(|pf| pf.protocol == PortProtocol::Tcp)
-    {
-        // TCP device
-        let bus = bus.clone();
-        let device =
-            VirtualIpDevice::new(PortProtocol::Tcp, bus.clone(), config.max_transmission_unit);
-
-        // Start TCP Virtual Interface
-        let port_forwards = config.port_forwards.clone();
-        let iface = TcpVirtualInterface::new(port_forwards, bus, config.source_peer_ip);
-        tokio::spawn(async move { iface.poll_loop(device).await });
-    }
-
-    if config
-        .port_forwards
-        .iter()
-        .any(|pf| pf.protocol == PortProtocol::Udp)
-    {
-        // UDP device
-        let bus = bus.clone();
-        let device =
-            VirtualIpDevice::new(PortProtocol::Udp, bus.clone(), config.max_transmission_unit);
-
-        // Start UDP Virtual Interface
-        let port_forwards = config.port_forwards.clone();
-        let iface = UdpVirtualInterface::new(port_forwards, bus, config.source_peer_ip);
-        tokio::spawn(async move { iface.poll_loop(device).await });
-    }
-
-    {
-        let port_forwards = config.port_forwards;
-        let source_peer_ip = config.source_peer_ip;
-
-        port_forwards
-            .into_iter()
-            .map(|pf| {
-                (
-                    pf,
-                    wg.clone(),
-                    tcp_port_pool.clone(),
-                    udp_port_pool.clone(),
-                    bus.clone(),
-                )
-            })
-            .for_each(move |(pf, wg, tcp_port_pool, udp_port_pool, bus)| {
-                tokio::spawn(async move {
-                    tunnel::port_forward(pf, source_peer_ip, tcp_port_pool, udp_port_pool, wg, bus)
-                        .await
-                        .unwrap_or_else(|e| error!("Port-forward failed for {} : {}", pf, e))
-                });
-            });
-    }
+    onetun::start_tunnels(config, bus).await?;
 
     futures::future::pending().await
 }
 
+#[cfg(not(feature = "bin"))]
+fn main() -> anyhow::Result<()> {
+    Err(anyhow::anyhow!("Binary compiled without 'bin' feature"))
+}
+
 #[cfg(feature = "bin")]
-fn init_logger(config: &Config) -> anyhow::Result<()> {
+fn init_logger(config: &onetun::config::Config) -> anyhow::Result<()> {
+    use anyhow::Context;
+
     let mut builder = pretty_env_logger::formatted_timed_builder();
     builder.parse_filters(&config.log);
     builder