Add SOCKS5 proxy support for peer and Esplora (#24)

Thread an optional socks5_proxy_addr through Config, Builder,
ConnectionManager, and EsploraChainSource so all outbound
connections can be routed through a SOCKS5 proxy (e.g. Tor).

Peer connections branch between connect_outbound_via_socks5 and
the existing connect_outbound. The two async fns return different
opaque Future types, so we Box::pin in each branch to erase the
type before the shared match block.

Esplora passes socks5://<addr> to esplora_client::Builder::proxy,
which uses reqwest's built-in SOCKS5 support under the hood.

Bumps rust-lightning to lsp-0.2.0_socks-support (adf445e5) which
adds the connect_outbound_via_socks5 function behind a "socks"
feature flag on lightning-net-tokio.

Electrum proxy support deferred to a follow-up.

Author: amackillop

Cargo.toml

@@ -42,17 +42,17 @@ default = []
 # lightning-macros = { version = "0.2.0" }
 
 # Branch: https://github.com/moneydevkit/rust-lightning/tree/lsp-0.2.0_accept-underpaying-htlcs_with_timing_logs
-lightning = { git = "https://github.com/moneydevkit/rust-lightning", rev = "dbc5bf8eb96d72456939d0ba539b7f00618e8ace", features = ["std"] }
-lightning-types = { git = "https://github.com/moneydevkit/rust-lightning", rev = "dbc5bf8eb96d72456939d0ba539b7f00618e8ace" }
-lightning-invoice = { git = "https://github.com/moneydevkit/rust-lightning", rev = "dbc5bf8eb96d72456939d0ba539b7f00618e8ace", features = ["std"] }
-lightning-net-tokio = { git = "https://github.com/moneydevkit/rust-lightning", rev = "dbc5bf8eb96d72456939d0ba539b7f00618e8ace" }
-lightning-persister = { git = "https://github.com/moneydevkit/rust-lightning", rev = "dbc5bf8eb96d72456939d0ba539b7f00618e8ace", features = ["tokio"] }
-lightning-background-processor = { git = "https://github.com/moneydevkit/rust-lightning", rev = "dbc5bf8eb96d72456939d0ba539b7f00618e8ace" }
-lightning-rapid-gossip-sync = { git = "https://github.com/moneydevkit/rust-lightning", rev = "dbc5bf8eb96d72456939d0ba539b7f00618e8ace" }
-lightning-block-sync = { git = "https://github.com/moneydevkit/rust-lightning", rev = "dbc5bf8eb96d72456939d0ba539b7f00618e8ace", features = ["rest-client", "rpc-client", "tokio"] }
-lightning-transaction-sync = { git = "https://github.com/moneydevkit/rust-lightning", rev = "dbc5bf8eb96d72456939d0ba539b7f00618e8ace", features = ["esplora-async-https", "time", "electrum-rustls-ring"] }
-lightning-liquidity = { git = "https://github.com/moneydevkit/rust-lightning", rev = "dbc5bf8eb96d72456939d0ba539b7f00618e8ace", features = ["std"] }
-lightning-macros = { git = "https://github.com/moneydevkit/rust-lightning", rev = "dbc5bf8eb96d72456939d0ba539b7f00618e8ace" }
+lightning = { git = "https://github.com/moneydevkit/rust-lightning", rev = "f56f47fe6c874771cd079faaacf96c42b32fbe72", features = ["std"] }
+lightning-types = { git = "https://github.com/moneydevkit/rust-lightning", rev = "f56f47fe6c874771cd079faaacf96c42b32fbe72" }
+lightning-invoice = { git = "https://github.com/moneydevkit/rust-lightning", rev = "f56f47fe6c874771cd079faaacf96c42b32fbe72", features = ["std"] }
+lightning-net-tokio = { git = "https://github.com/moneydevkit/rust-lightning", rev = "f56f47fe6c874771cd079faaacf96c42b32fbe72", features = ["socks"] }
+lightning-persister = { git = "https://github.com/moneydevkit/rust-lightning", rev = "f56f47fe6c874771cd079faaacf96c42b32fbe72", features = ["tokio"] }
+lightning-background-processor = { git = "https://github.com/moneydevkit/rust-lightning", rev = "f56f47fe6c874771cd079faaacf96c42b32fbe72" }
+lightning-rapid-gossip-sync = { git = "https://github.com/moneydevkit/rust-lightning", rev = "f56f47fe6c874771cd079faaacf96c42b32fbe72" }
+lightning-block-sync = { git = "https://github.com/moneydevkit/rust-lightning", rev = "f56f47fe6c874771cd079faaacf96c42b32fbe72", features = ["rest-client", "rpc-client", "tokio"] }
+lightning-transaction-sync = { git = "https://github.com/moneydevkit/rust-lightning", rev = "f56f47fe6c874771cd079faaacf96c42b32fbe72", features = ["esplora-async-https", "time", "electrum-rustls-ring"] }
+lightning-liquidity = { git = "https://github.com/moneydevkit/rust-lightning", rev = "f56f47fe6c874771cd079faaacf96c42b32fbe72", features = ["std"] }
+lightning-macros = { git = "https://github.com/moneydevkit/rust-lightning", rev = "f56f47fe6c874771cd079faaacf96c42b32fbe72" }
 
 #lightning = { path = "../rust-lightning/lightning", features = ["std"] }
 #lightning-types = { path = "../rust-lightning/lightning-types" }
@@ -100,8 +100,8 @@ winapi = { version = "0.3", features = ["winbase"] }
 
 [dev-dependencies]
 # lightning = { version = "0.2.0", features = ["std", "_test_utils"] }
-# Branch: https://github.com/moneydevkit/rust-lightning/commits/lsp-0.2.0_accept-underpaying-htlcs
-lightning = { git = "https://github.com/moneydevkit/rust-lightning", rev = "dbc5bf8eb96d72456939d0ba539b7f00618e8ace", features = ["std", "_test_utils"] }
+# Branch: https://github.com/moneydevkit/rust-lightning/commits/lsp-0.2.0_accept-underpaying-htlcs_with_timing_logs
+lightning = { git = "https://github.com/moneydevkit/rust-lightning", rev = "f56f47fe6c874771cd079faaacf96c42b32fbe72", features = ["std", "_test_utils"] }
 #lightning = { path = "../rust-lightning/lightning", features = ["std", "_test_utils"] }
 proptest = "1.0.0"
 regex = "1.5.6"

src/builder.rs

@@ -606,6 +606,12 @@ impl NodeBuilder {
 		Ok(self)
 	}
 
+	/// Sets the SOCKS5 proxy address for all outbound connections.
+	pub fn set_socks5_proxy(&mut self, addr: std::net::SocketAddr) -> &mut Self {
+		self.config.socks5_proxy_addr = Some(addr);
+		self
+	}
+
 	/// Sets the role of the node in an asynchronous payments context.
 	///
 	/// See <https://github.com/lightning/bolts/pull/1149> for more information about the async payments protocol.
@@ -1135,6 +1141,11 @@ impl ArcedNodeBuilder {
 		self.inner.write().unwrap().set_node_alias(node_alias).map(|_| ())
 	}
 
+	/// Sets the SOCKS5 proxy address for all outbound connections.
+	pub fn set_socks5_proxy(&self, addr: std::net::SocketAddr) {
+		self.inner.write().unwrap().set_socks5_proxy(addr);
+	}
+
 	/// Sets the role of the node in an asynchronous payments context.
 	pub fn set_async_payments_role(
 		&self, role: Option<AsyncPaymentsRole>,
@@ -1940,7 +1951,7 @@ fn build_with_store_internal(
 	);
 
 	let connection_manager =
-		Arc::new(ConnectionManager::new(Arc::clone(&peer_manager), Arc::clone(&logger)));
+		Arc::new(ConnectionManager::new(Arc::clone(&peer_manager), config.socks5_proxy_addr, Arc::clone(&logger)));
 
 	// read_output_sweeper (peer_info was already read in the spawned group above)
 	let step_start = Instant::now();

src/chain/esplora.rs

@@ -57,6 +57,10 @@ impl EsploraChainSource {
 			client_builder = client_builder.header(header_name, header_value);
 		}
 
+		if let Some(proxy_addr) = config.socks5_proxy_addr {
+			client_builder = client_builder.proxy(&format!("socks5://{}", proxy_addr));
+		}
+
 		let esplora_client = client_builder.build_async().unwrap();
 		let tx_sync =
 			Arc::new(EsploraSyncClient::from_client(esplora_client.clone(), Arc::clone(&logger)));

src/config.rs

@@ -8,6 +8,7 @@
 //! Objects for configuring the node.
 
 use std::fmt;
+use std::net::SocketAddr;
 use std::time::Duration;
 
 use bitcoin::secp256k1::PublicKey;
@@ -188,6 +189,11 @@ pub struct Config {
 	/// The parameters used to configure the [`lightning::routing::scoring::ProbabilisticScorer`]
 	/// used by the node.
 	pub scoring_parameters: ProbabilisticScoringParameters,
+	/// Optional SOCKS5 proxy address for all outbound connections (peer, Esplora, Electrum).
+	///
+	/// When set, Lightning peer connections and chain-source HTTP requests will be routed
+	/// through the given SOCKS5 proxy.
+	pub socks5_proxy_addr: Option<SocketAddr>,
 }
 
 impl Default for Config {
@@ -203,6 +209,7 @@ impl Default for Config {
 			route_parameters: None,
 			node_alias: None,
 			scoring_parameters: ProbabilisticScoringParameters::default(),
+			socks5_proxy_addr: None,
 		}
 	}
 }

src/connection.rs

@@ -6,8 +6,10 @@
 // accordance with one or both of these licenses.
 
 use std::collections::hash_map::{self, HashMap};
-use std::net::ToSocketAddrs;
+use std::future::Future;
+use std::net::{SocketAddr, ToSocketAddrs};
 use std::ops::Deref;
+use std::pin::Pin;
 use std::sync::{Arc, Mutex};
 use std::time::Duration;
 
@@ -25,16 +27,19 @@ where
 	pending_connections:
 		Mutex<HashMap<PublicKey, Vec<tokio::sync::oneshot::Sender<Result<(), Error>>>>>,
 	peer_manager: Arc<PeerManager>,
+	socks5_proxy_addr: Option<SocketAddr>,
 	logger: L,
 }
 
 impl<L: Deref + Clone + Sync + Send> ConnectionManager<L>
 where
 	L::Target: LdkLogger,
 {
-	pub(crate) fn new(peer_manager: Arc<PeerManager>, logger: L) -> Self {
+	pub(crate) fn new(
+		peer_manager: Arc<PeerManager>, socks5_proxy_addr: Option<SocketAddr>, logger: L,
+	) -> Self {
 		let pending_connections = Mutex::new(HashMap::new());
-		Self { pending_connections, peer_manager, logger }
+		Self { pending_connections, peer_manager, socks5_proxy_addr, logger }
 	}
 
 	pub(crate) async fn connect_peer_if_necessary(
@@ -78,15 +83,29 @@ where
 				Error::InvalidSocketAddress
 			})?;
 
-		let connection_future = lightning_net_tokio::connect_outbound(
-			Arc::clone(&self.peer_manager),
-			node_id,
-			socket_addr,
-		);
-
-		let res = match connection_future.await {
-			Some(connection_closed_future) => {
-				let mut connection_closed_future = Box::pin(connection_closed_future);
+		let connection_future =
+			if let Some(proxy_addr) = self.socks5_proxy_addr {
+				log_info!(self.logger, "Connecting via SOCKS5 proxy {} to peer: {}@{}", proxy_addr, node_id, addr);
+				lightning_net_tokio::connect_outbound_via_socks5(
+					Arc::clone(&self.peer_manager),
+					node_id,
+					socket_addr,
+					proxy_addr,
+				)
+				.await
+				.map(|f| Box::pin(f) as Pin<Box<dyn Future<Output = ()> + Send>>)
+			} else {
+				lightning_net_tokio::connect_outbound(
+					Arc::clone(&self.peer_manager),
+					node_id,
+					socket_addr,
+				)
+				.await
+				.map(|f| Box::pin(f) as Pin<Box<dyn Future<Output = ()> + Send>>)
+			};
+
+		let res = match connection_future {
+			Some(mut connection_closed_future) => {
 				loop {
 					tokio::select! {
 						_ = &mut connection_closed_future => {