From 731bceb088c033a87782c0397b4573324596c053 Mon Sep 17 00:00:00 2001
From: bitwalt <walterm21@proton.me>
Date: Thu, 26 Mar 2026 19:12:14 +0100
Subject: [PATCH] test: demonstrate rgb_send_lock stuck after peer shutdown

Open a vanilla channel from node1 to node2, shut down node2 before
the funding TX is mined (ChannelPending never fires), then verify that
node1 cannot open a new channel to node3 because rgb_send_lock is
never released.

The ChannelClosed event handler does not reset rgb_send_lock, leaving
the node permanently unable to open new channels.

Ref: https://github.com/RGB-Tools/rgb-lightning-node/issues/111
---
 src/test/channel_closed_lock_release.rs | 116 ++++++++++++++++++++++++
 src/test/mod.rs                         |   1 +
 2 files changed, 117 insertions(+)
 create mode 100644 src/test/channel_closed_lock_release.rs

diff --git a/src/test/channel_closed_lock_release.rs b/src/test/channel_closed_lock_release.rs
new file mode 100644
index 00000000..cbcf5152
--- /dev/null
+++ b/src/test/channel_closed_lock_release.rs
@@ -0,0 +1,116 @@
+use super::*;
+
+const TEST_DIR_BASE: &str = "tmp/channel_closed_lock_release/";
+
+/// Test that verifies the rgb_send_lock is released after a channel's peer
+/// disconnects before funding is generated.
+///
+/// Scenario: node1 opens a channel to node2, then immediately disconnects
+/// the peer. If the disconnect happens before FundingGenerationReady, LDK
+/// emits ChannelClosed with channel_funding_txo = None. Without the fix,
+/// the lock is never released and node1 cannot open new channels.
+#[serial_test::serial]
+#[tokio::test(flavor = "multi_thread", worker_threads = 1)]
+#[traced_test]
+async fn channel_closed_no_funding_releases_openchannel_lock() {
+    initialize();
+
+    let test_dir_node1 = format!("{TEST_DIR_BASE}node1");
+    let test_dir_node2 = format!("{TEST_DIR_BASE}node2");
+    let test_dir_node3 = format!("{TEST_DIR_BASE}node3");
+    let (node1_addr, _) = start_node(&test_dir_node1, NODE1_PEER_PORT, false).await;
+    let (node2_addr, _) = start_node(&test_dir_node2, NODE2_PEER_PORT, false).await;
+
+    fund_and_create_utxos(node1_addr, None).await;
+    fund_and_create_utxos(node2_addr, None).await;
+
+    let node2_info = node_info(node2_addr).await;
+    let node2_pubkey = node2_info.pubkey;
+
+    // Open a vanilla channel from node1 to node2 (just the API call, don't wait for funding)
+    let open_channel_payload = OpenChannelRequest {
+        peer_pubkey_and_opt_addr: format!(
+            "{}@127.0.0.1:{}",
+            node2_pubkey, NODE2_PEER_PORT
+        ),
+        capacity_sat: 100_000,
+        push_msat: 0,
+        asset_amount: None,
+        asset_id: None,
+        push_asset_amount: None,
+        public: true,
+        with_anchors: true,
+        fee_base_msat: None,
+        fee_proportional_millionths: None,
+        temporary_channel_id: None,
+    };
+    let res = reqwest::Client::new()
+        .post(format!("http://{node1_addr}/openchannel"))
+        .json(&open_channel_payload)
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(res.status(), reqwest::StatusCode::OK);
+
+    // Shut down node2 so LDK on node1 detects the peer going offline.
+    // This triggers ChannelClosed (and possibly DiscardFunding).
+    // The lock should be released regardless of which events fire.
+    shutdown(&[node2_addr]).await;
+
+    // Give LDK time to detect the disconnect and process events
+    tokio::time::sleep(std::time::Duration::from_secs(10)).await;
+
+    // Start node3 and try to open a new channel from node1
+    let (node3_addr, _) = start_node(&test_dir_node3, NODE3_PEER_PORT, false).await;
+    fund_and_create_utxos(node3_addr, None).await;
+    let node3_info = node_info(node3_addr).await;
+    let node3_pubkey = node3_info.pubkey;
+
+    // Poll until the rgb_send_lock is released and we can open a new channel.
+    // Without the fix, the lock stays stuck indefinitely and every attempt returns 403.
+    let t_0 = OffsetDateTime::now_utc();
+    loop {
+        let open_channel_payload_2 = OpenChannelRequest {
+            peer_pubkey_and_opt_addr: format!(
+                "{}@127.0.0.1:{}",
+                node3_pubkey, NODE3_PEER_PORT
+            ),
+            capacity_sat: 50_000,
+            push_msat: 0,
+            asset_amount: None,
+            asset_id: None,
+            push_asset_amount: None,
+            public: true,
+            with_anchors: true,
+            fee_base_msat: None,
+            fee_proportional_millionths: None,
+            temporary_channel_id: None,
+        };
+        let res = reqwest::Client::new()
+            .post(format!("http://{node1_addr}/openchannel"))
+            .json(&open_channel_payload_2)
+            .send()
+            .await
+            .unwrap();
+
+        if res.status() == reqwest::StatusCode::OK {
+            break;
+        }
+        assert_eq!(
+            res.status(),
+            reqwest::StatusCode::FORBIDDEN,
+            "unexpected status code"
+        );
+
+        tokio::time::sleep(std::time::Duration::from_secs(1)).await;
+
+        if (OffsetDateTime::now_utc() - t_0).as_seconds_f32() > 60.0 {
+            panic!(
+                "rgb_send_lock remained stuck for 60s after peer disconnect — \
+                 node cannot open new channels"
+            );
+        }
+    }
+
+    shutdown(&[node1_addr, node3_addr]).await;
+}
diff --git a/src/test/mod.rs b/src/test/mod.rs
index 7b57051a..29d9a4c5 100644
--- a/src/test/mod.rs
+++ b/src/test/mod.rs
@@ -1919,6 +1919,7 @@ pub fn mock_fee(fee: u32) -> u32 {
 
 mod authentication;
 mod backup_and_restore;
+mod channel_closed_lock_release;
 mod close_coop_nobtc_acceptor;
 mod close_coop_other_side;
 mod close_coop_standard;