Make ChannelMonitor clonable again
[rust-lightning] / lightning / src / chain / channelmonitor.rs
index f91af7cc66cd3c9a3ea70b07c9cb5aef82bcca86..6daab991922f160be0d4062f5cb392545f69789e 100644 (file)
@@ -256,7 +256,7 @@ impl_writeable_tlv_based!(HolderSignedTx, {
 
 /// We use this to track static counterparty commitment transaction data and to generate any
 /// justice or 2nd-stage preimage/timeout transactions.
-#[derive(PartialEq)]
+#[derive(Clone, PartialEq)]
 struct CounterpartyCommitmentParameters {
        counterparty_delayed_payment_base_key: PublicKey,
        counterparty_htlc_base_key: PublicKey,
@@ -310,7 +310,7 @@ impl Readable for CounterpartyCommitmentParameters {
 /// transaction causing it.
 ///
 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
-#[derive(PartialEq)]
+#[derive(Clone, PartialEq)]
 struct OnchainEventEntry {
        txid: Txid,
        height: u32,
@@ -346,7 +346,7 @@ impl OnchainEventEntry {
 
 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
-#[derive(PartialEq)]
+#[derive(Clone, PartialEq)]
 enum OnchainEvent {
        /// An outbound HTLC failing after a transaction is confirmed. Used
        ///  * when an outbound HTLC output is spent by us after the HTLC timed out
@@ -566,7 +566,7 @@ pub enum Balance {
 }
 
 /// An HTLC which has been irrevocably resolved on-chain, and has reached ANTI_REORG_DELAY.
-#[derive(PartialEq)]
+#[derive(Clone, PartialEq)]
 struct IrrevocablyResolvedHTLC {
        commitment_tx_output_idx: u32,
        /// Only set if the HTLC claim was ours using a payment preimage
@@ -601,6 +601,13 @@ pub struct ChannelMonitor<Signer: Sign> {
        inner: Mutex<ChannelMonitorImpl<Signer>>,
 }
 
+impl<Signer: Sign> Clone for ChannelMonitor<Signer> {
+       fn clone(&self) -> Self {
+               Self { inner: Mutex::new(self.inner.lock().unwrap().clone()) }
+       }
+}
+
+#[derive(Clone)]
 pub(crate) struct ChannelMonitorImpl<Signer: Sign> {
        latest_update_id: u64,
        commitment_transaction_number_obscure_factor: u64,
@@ -965,6 +972,13 @@ impl<Signer: Sign> Writeable for ChannelMonitorImpl<Signer> {
 }
 
 impl<Signer: Sign> ChannelMonitor<Signer> {
+       /// For lockorder enforcement purposes, we need to have a single site which constructs the
+       /// `inner` mutex, otherwise cases where we lock two monitors at the same time (eg in our
+       /// PartialEq implementation) we may decide a lockorder violation has occurred.
+       fn from_impl(imp: ChannelMonitorImpl<Signer>) -> Self {
+               ChannelMonitor { inner: Mutex::new(imp) }
+       }
+
        pub(crate) fn new(secp_ctx: Secp256k1<secp256k1::All>, keys: Signer, shutdown_script: Option<Script>,
                          on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
                          channel_parameters: &ChannelTransactionParameters,
@@ -1012,60 +1026,58 @@ impl<Signer: Sign> ChannelMonitor<Signer> {
                let mut outputs_to_watch = HashMap::new();
                outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
 
-               ChannelMonitor {
-                       inner: Mutex::new(ChannelMonitorImpl {
-                               latest_update_id: 0,
-                               commitment_transaction_number_obscure_factor,
+               Self::from_impl(ChannelMonitorImpl {
+                       latest_update_id: 0,
+                       commitment_transaction_number_obscure_factor,
 
-                               destination_script: destination_script.clone(),
-                               broadcasted_holder_revokable_script: None,
-                               counterparty_payment_script,
-                               shutdown_script,
+                       destination_script: destination_script.clone(),
+                       broadcasted_holder_revokable_script: None,
+                       counterparty_payment_script,
+                       shutdown_script,
 
-                               channel_keys_id,
-                               holder_revocation_basepoint,
-                               funding_info,
-                               current_counterparty_commitment_txid: None,
-                               prev_counterparty_commitment_txid: None,
+                       channel_keys_id,
+                       holder_revocation_basepoint,
+                       funding_info,
+                       current_counterparty_commitment_txid: None,
+                       prev_counterparty_commitment_txid: None,
 
-                               counterparty_commitment_params,
-                               funding_redeemscript,
-                               channel_value_satoshis,
-                               their_cur_per_commitment_points: None,
+                       counterparty_commitment_params,
+                       funding_redeemscript,
+                       channel_value_satoshis,
+                       their_cur_per_commitment_points: None,
 
-                               on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
+                       on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
 
-                               commitment_secrets: CounterpartyCommitmentSecrets::new(),
-                               counterparty_claimable_outpoints: HashMap::new(),
-                               counterparty_commitment_txn_on_chain: HashMap::new(),
-                               counterparty_hash_commitment_number: HashMap::new(),
+                       commitment_secrets: CounterpartyCommitmentSecrets::new(),
+                       counterparty_claimable_outpoints: HashMap::new(),
+                       counterparty_commitment_txn_on_chain: HashMap::new(),
+                       counterparty_hash_commitment_number: HashMap::new(),
 
-                               prev_holder_signed_commitment_tx: None,
-                               current_holder_commitment_tx: holder_commitment_tx,
-                               current_counterparty_commitment_number: 1 << 48,
-                               current_holder_commitment_number,
+                       prev_holder_signed_commitment_tx: None,
+                       current_holder_commitment_tx: holder_commitment_tx,
+                       current_counterparty_commitment_number: 1 << 48,
+                       current_holder_commitment_number,
 
-                               payment_preimages: HashMap::new(),
-                               pending_monitor_events: Vec::new(),
-                               pending_events: Vec::new(),
+                       payment_preimages: HashMap::new(),
+                       pending_monitor_events: Vec::new(),
+                       pending_events: Vec::new(),
 
-                               onchain_events_awaiting_threshold_conf: Vec::new(),
-                               outputs_to_watch,
+                       onchain_events_awaiting_threshold_conf: Vec::new(),
+                       outputs_to_watch,
 
-                               onchain_tx_handler,
+                       onchain_tx_handler,
 
-                               lockdown_from_offchain: false,
-                               holder_tx_signed: false,
-                               funding_spend_seen: false,
-                               funding_spend_confirmed: None,
-                               htlcs_resolved_on_chain: Vec::new(),
+                       lockdown_from_offchain: false,
+                       holder_tx_signed: false,
+                       funding_spend_seen: false,
+                       funding_spend_confirmed: None,
+                       htlcs_resolved_on_chain: Vec::new(),
 
-                               best_block,
-                               counterparty_node_id: Some(counterparty_node_id),
+                       best_block,
+                       counterparty_node_id: Some(counterparty_node_id),
 
-                               secp_ctx,
-                       }),
-               }
+                       secp_ctx,
+               })
        }
 
        #[cfg(test)]
@@ -1209,6 +1221,14 @@ impl<Signer: Sign> ChannelMonitor<Signer> {
                self.inner.lock().unwrap().get_cur_holder_commitment_number()
        }
 
+       /// Gets the `node_id` of the counterparty for this channel.
+       ///
+       /// Will be `None` for channels constructed on LDK versions prior to 0.0.110 and always `Some`
+       /// otherwise.
+       pub fn get_counterparty_node_id(&self) -> Option<PublicKey> {
+               self.inner.lock().unwrap().counterparty_node_id
+       }
+
        /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
        /// the Channel was out-of-date. You may use it to get a broadcastable holder toxic tx in case of
        /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our counterparty side knows
@@ -3361,60 +3381,58 @@ impl<'a, Signer: Sign, K: KeysInterface<Signer = Signer>> ReadableArgs<&'a K>
                let mut secp_ctx = Secp256k1::new();
                secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes());
 
-               Ok((best_block.block_hash(), ChannelMonitor {
-                       inner: Mutex::new(ChannelMonitorImpl {
-                               latest_update_id,
-                               commitment_transaction_number_obscure_factor,
+               Ok((best_block.block_hash(), ChannelMonitor::from_impl(ChannelMonitorImpl {
+                       latest_update_id,
+                       commitment_transaction_number_obscure_factor,
 
-                               destination_script,
-                               broadcasted_holder_revokable_script,
-                               counterparty_payment_script,
-                               shutdown_script,
+                       destination_script,
+                       broadcasted_holder_revokable_script,
+                       counterparty_payment_script,
+                       shutdown_script,
 
-                               channel_keys_id,
-                               holder_revocation_basepoint,
-                               funding_info,
-                               current_counterparty_commitment_txid,
-                               prev_counterparty_commitment_txid,
+                       channel_keys_id,
+                       holder_revocation_basepoint,
+                       funding_info,
+                       current_counterparty_commitment_txid,
+                       prev_counterparty_commitment_txid,
 
-                               counterparty_commitment_params,
-                               funding_redeemscript,
-                               channel_value_satoshis,
-                               their_cur_per_commitment_points,
+                       counterparty_commitment_params,
+                       funding_redeemscript,
+                       channel_value_satoshis,
+                       their_cur_per_commitment_points,
 
-                               on_holder_tx_csv,
+                       on_holder_tx_csv,
 
-                               commitment_secrets,
-                               counterparty_claimable_outpoints,
-                               counterparty_commitment_txn_on_chain,
-                               counterparty_hash_commitment_number,
+                       commitment_secrets,
+                       counterparty_claimable_outpoints,
+                       counterparty_commitment_txn_on_chain,
+                       counterparty_hash_commitment_number,
 
-                               prev_holder_signed_commitment_tx,
-                               current_holder_commitment_tx,
-                               current_counterparty_commitment_number,
-                               current_holder_commitment_number,
+                       prev_holder_signed_commitment_tx,
+                       current_holder_commitment_tx,
+                       current_counterparty_commitment_number,
+                       current_holder_commitment_number,
 
-                               payment_preimages,
-                               pending_monitor_events: pending_monitor_events.unwrap(),
-                               pending_events,
+                       payment_preimages,
+                       pending_monitor_events: pending_monitor_events.unwrap(),
+                       pending_events,
 
-                               onchain_events_awaiting_threshold_conf,
-                               outputs_to_watch,
+                       onchain_events_awaiting_threshold_conf,
+                       outputs_to_watch,
 
-                               onchain_tx_handler,
+                       onchain_tx_handler,
 
-                               lockdown_from_offchain,
-                               holder_tx_signed,
-                               funding_spend_seen: funding_spend_seen.unwrap(),
-                               funding_spend_confirmed,
-                               htlcs_resolved_on_chain: htlcs_resolved_on_chain.unwrap(),
+                       lockdown_from_offchain,
+                       holder_tx_signed,
+                       funding_spend_seen: funding_spend_seen.unwrap(),
+                       funding_spend_confirmed,
+                       htlcs_resolved_on_chain: htlcs_resolved_on_chain.unwrap(),
 
-                               best_block,
-                               counterparty_node_id,
+                       best_block,
+                       counterparty_node_id,
 
-                               secp_ctx,
-                       }),
-               }))
+                       secp_ctx,
+               })))
        }
 }