From: jbesraa Date: Fri, 29 Mar 2024 05:56:23 +0000 (+0300) Subject: Add `ChannelMonitor::is_fully_resolved` function X-Git-Tag: v0.0.123-beta~2^2~1 X-Git-Url: http://git.bitcoin.ninja/index.cgi?p=rust-lightning;a=commitdiff_plain;h=9a1649c2b2ca5b348d2e58624ccc936197bcb4d0 Add `ChannelMonitor::is_fully_resolved` function Checks if the monitor is fully resolved. Resolved monitor is one that has claimed all of its ouputs and balacnes. This function returns true only if `get_claimable_balances` has been empty for at least 2016 blocks. --- diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs index c2d3a43b..c05b6b30 100644 --- a/lightning/src/chain/channelmonitor.rs +++ b/lightning/src/chain/channelmonitor.rs @@ -935,6 +935,9 @@ pub(crate) struct ChannelMonitorImpl { /// Ordering of tuple data: (their_per_commitment_point, feerate_per_kw, to_broadcaster_sats, /// to_countersignatory_sats) initial_counterparty_commitment_info: Option<(PublicKey, u32, u64, u64)>, + + /// The first block height at which we had no remaining claimable balances. + balances_empty_height: Option, } /// Transaction outputs to watch for on-chain spends. @@ -1145,6 +1148,7 @@ impl Writeable for ChannelMonitorImpl ChannelMonitor { best_block, counterparty_node_id: Some(counterparty_node_id), initial_counterparty_commitment_info: None, + balances_empty_height: None, }) } @@ -1856,6 +1861,52 @@ impl ChannelMonitor { spendable_outputs } + /// Checks if the monitor is fully resolved. Resolved monitor is one that has claimed all of + /// its outputs and balances (i.e. [`Self::get_claimable_balances`] returns an empty set). + /// + /// This function returns true only if [`Self::get_claimable_balances`] has been empty for at least + /// 2016 blocks as an additional protection against any bugs resulting in spuriously empty balance sets. + pub fn is_fully_resolved(&self, logger: &L) -> bool { + let mut is_all_funds_claimed = self.get_claimable_balances().is_empty(); + let current_height = self.current_best_block().height; + let mut inner = self.inner.lock().unwrap(); + + if is_all_funds_claimed { + if !inner.funding_spend_seen { + debug_assert!(false, "We should see funding spend by the time a monitor clears out"); + is_all_funds_claimed = false; + } + } + + match (inner.balances_empty_height, is_all_funds_claimed) { + (Some(balances_empty_height), true) => { + // Claimed all funds, check if reached the blocks threshold. + const BLOCKS_THRESHOLD: u32 = 4032; // ~four weeks + return current_height >= balances_empty_height + BLOCKS_THRESHOLD; + }, + (Some(_), false) => { + // previously assumed we claimed all funds, but we have new funds to claim. + // Should not happen in practice. + debug_assert!(false, "Thought we were done claiming funds, but claimable_balances now has entries"); + log_error!(logger, + "WARNING: LDK thought it was done claiming all the available funds in the ChannelMonitor for channel {}, but later decided it had more to claim. This is potentially an important bug in LDK, please report it at https://github.com/lightningdevkit/rust-lightning/issues/new", + inner.get_funding_txo().0); + inner.balances_empty_height = None; + false + }, + (None, true) => { + // Claimed all funds but `balances_empty_height` is None. It is set to the + // current block height. + inner.balances_empty_height = Some(current_height); + false + }, + (None, false) => { + // Have funds to claim. + false + }, + } + } + #[cfg(test)] pub fn get_counterparty_payment_script(&self) -> ScriptBuf { self.inner.lock().unwrap().counterparty_payment_script.clone() @@ -4632,6 +4683,7 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP let mut spendable_txids_confirmed = Some(Vec::new()); let mut counterparty_fulfilled_htlcs = Some(new_hash_map()); let mut initial_counterparty_commitment_info = None; + let mut balances_empty_height = None; let mut channel_id = None; read_tlv_fields!(reader, { (1, funding_spend_confirmed, option), @@ -4644,6 +4696,7 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP (15, counterparty_fulfilled_htlcs, option), (17, initial_counterparty_commitment_info, option), (19, channel_id, option), + (21, balances_empty_height, option), }); // `HolderForceClosedWithInfo` replaced `HolderForceClosed` in v0.0.122. If we have both @@ -4722,6 +4775,7 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP best_block, counterparty_node_id, initial_counterparty_commitment_info, + balances_empty_height, }))) } }