use bitcoin::blockdata::block::{Block, BlockHeader};
use chain;
-use chain::Filter;
+use chain::{Filter, WatchedOutput};
use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
use chain::channelmonitor;
use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, MonitorEvent, Persist};
/// descendants of such transactions. It is not necessary to re-fetch the block to obtain
/// updated `txdata`.
pub fn block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
+ let mut dependent_txdata = Vec::new();
let monitors = self.monitors.read().unwrap();
for monitor in monitors.values() {
let mut txn_outputs = monitor.block_connected(header, txdata, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
+ // Register any new outputs with the chain source for filtering, storing any dependent
+ // transactions from within the block that previously had not been included in txdata.
if let Some(ref chain_source) = self.chain_source {
+ let block_hash = header.block_hash();
for (txid, outputs) in txn_outputs.drain(..) {
for (idx, output) in outputs.iter() {
- chain_source.register_output(&OutPoint { txid, index: *idx as u16 }, &output.script_pubkey);
+ // Register any new outputs with the chain source for filtering and recurse
+ // if it indicates that there are dependent transactions within the block
+ // that had not been previously included in txdata.
+ let output = WatchedOutput {
+ block_hash: Some(block_hash),
+ outpoint: OutPoint { txid, index: *idx as u16 },
+ script_pubkey: output.script_pubkey.clone(),
+ };
+ if let Some(tx) = chain_source.register_output(output) {
+ dependent_txdata.push(tx);
+ }
}
}
}
}
+
+ // Recursively call for any dependent transactions that were identified by the chain source.
+ if !dependent_txdata.is_empty() {
+ dependent_txdata.sort_unstable_by_key(|(index, _tx)| *index);
+ dependent_txdata.dedup_by_key(|(index, _tx)| *index);
+ let txdata: Vec<_> = dependent_txdata.iter().map(|(index, tx)| (*index, tx)).collect();
+ self.block_connected(header, &txdata, height);
+ }
}
/// Dispatches to per-channel monitors, which are responsible for updating their on-chain view
pending_events
}
}
+
+#[cfg(test)]
+mod tests {
+ use ::{check_added_monitors, get_local_commitment_txn};
+ use ln::features::InitFeatures;
+ use ln::functional_test_utils::*;
+ use util::events::EventsProvider;
+ use util::events::MessageSendEventsProvider;
+ use util::test_utils::{OnRegisterOutput, TxOutReference};
+
+ /// Tests that in-block dependent transactions are processed by `block_connected` when not
+ /// included in `txdata` but returned by [`chain::Filter::register_output`]. For instance,
+ /// a (non-anchor) commitment transaction's HTLC output may be spent in the same block as the
+ /// commitment transaction itself. An Electrum client may filter the commitment transaction but
+ /// needs to return the HTLC transaction so it can be processed.
+ #[test]
+ fn connect_block_checks_dependent_transactions() {
+ let chanmon_cfgs = create_chanmon_cfgs(2);
+ let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
+ let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
+ let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
+ let channel = create_announced_chan_between_nodes(
+ &nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
+
+ // Send a payment, saving nodes[0]'s revoked commitment and HTLC-Timeout transactions.
+ let (commitment_tx, htlc_tx) = {
+ let payment_preimage = route_payment(&nodes[0], &vec!(&nodes[1])[..], 5_000_000).0;
+ let mut txn = get_local_commitment_txn!(nodes[0], channel.2);
+ claim_payment(&nodes[0], &vec!(&nodes[1])[..], payment_preimage, 5_000_000);
+
+ assert_eq!(txn.len(), 2);
+ (txn.remove(0), txn.remove(0))
+ };
+
+ // Set expectations on nodes[1]'s chain source to return dependent transactions.
+ let htlc_output = TxOutReference(commitment_tx.clone(), 0);
+ let to_local_output = TxOutReference(commitment_tx.clone(), 1);
+ let htlc_timeout_output = TxOutReference(htlc_tx.clone(), 0);
+ nodes[1].chain_source
+ .expect(OnRegisterOutput { with: htlc_output, returns: Some((1, htlc_tx)) })
+ .expect(OnRegisterOutput { with: to_local_output, returns: None })
+ .expect(OnRegisterOutput { with: htlc_timeout_output, returns: None });
+
+ // Notify nodes[1] that nodes[0]'s revoked commitment transaction was mined. The chain
+ // source should return the dependent HTLC transaction when the HTLC output is registered.
+ mine_transaction(&nodes[1], &commitment_tx);
+
+ // Clean up so uninteresting assertions don't fail.
+ check_added_monitors!(nodes[1], 1);
+ nodes[1].node.get_and_clear_pending_msg_events();
+ nodes[1].node.get_and_clear_pending_events();
+ }
+}
use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
use chain;
+use chain::WatchedOutput;
use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
use chain::transaction::{OutPoint, TransactionData};
use chain::keysinterface::{SpendableOutputDescriptor, StaticPaymentOutputDescriptor, DelayedPaymentOutputDescriptor, Sign, KeysInterface};
for (txid, outputs) in lock.get_outputs_to_watch().iter() {
for (index, script_pubkey) in outputs.iter() {
assert!(*index <= u16::max_value() as u32);
- filter.register_output(&OutPoint { txid: *txid, index: *index as u16 }, script_pubkey);
+ filter.register_output(WatchedOutput {
+ block_hash: None,
+ outpoint: OutPoint { txid: *txid, index: *index as u16 },
+ script_pubkey: script_pubkey.clone(),
+ });
}
}
}
use bitcoin::blockdata::block::{Block, BlockHeader};
use bitcoin::blockdata::script::Script;
-use bitcoin::blockdata::transaction::TxOut;
+use bitcoin::blockdata::transaction::{Transaction, TxOut};
use bitcoin::hash_types::{BlockHash, Txid};
use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, MonitorEvent};
/// a spending condition.
fn register_tx(&self, txid: &Txid, script_pubkey: &Script);
- /// Registers interest in spends of a transaction output identified by `outpoint` having
- /// `script_pubkey` as the spending condition.
- fn register_output(&self, outpoint: &OutPoint, script_pubkey: &Script);
+ /// Registers interest in spends of a transaction output.
+ ///
+ /// Optionally, when `output.block_hash` is set, should return any transaction spending the
+ /// output that is found in the corresponding block along with its index.
+ ///
+ /// This return value is useful for Electrum clients in order to supply in-block descendant
+ /// transactions which otherwise were not included. This is not necessary for other clients if
+ /// such descendant transactions were already included (e.g., when a BIP 157 client provides the
+ /// full block).
+ fn register_output(&self, output: WatchedOutput) -> Option<(usize, Transaction)>;
+}
+
+/// A transaction output watched by a [`ChannelMonitor`] for spends on-chain.
+///
+/// Used to convey to a [`Filter`] such an output with a given spending condition. Any transaction
+/// spending the output must be given to [`ChannelMonitor::block_connected`] either directly or via
+/// the return value of [`Filter::register_output`].
+///
+/// If `block_hash` is `Some`, this indicates the output was created in the corresponding block and
+/// may have been spent there. See [`Filter::register_output`] for details.
+///
+/// [`ChannelMonitor`]: channelmonitor::ChannelMonitor
+/// [`ChannelMonitor::block_connected`]: channelmonitor::ChannelMonitor::block_connected
+pub struct WatchedOutput {
+ /// First block where the transaction output may have been spent.
+ pub block_hash: Option<BlockHash>,
+
+ /// Outpoint identifying the transaction output.
+ pub outpoint: OutPoint,
+
+ /// Spending condition of the transaction output.
+ pub script_pubkey: Script,
}
impl<T: Listen> Listen for std::ops::Deref<Target = T> {
}
}
-#[cfg(test)]
+/// Returns any local commitment transactions for the channel.
+#[macro_export]
macro_rules! get_local_commitment_txn {
($node: expr, $channel_id: expr) => {
{
// licenses.
use chain;
+use chain::WatchedOutput;
use chain::chaininterface;
use chain::chaininterface::ConfirmationTarget;
use chain::chainmonitor;
use std::sync::{Mutex, Arc};
use std::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
use std::{cmp, mem};
-use std::collections::{HashMap, HashSet};
+use std::collections::{HashMap, HashSet, VecDeque};
use chain::keysinterface::InMemorySigner;
pub struct TestVecWriter(pub Vec<u8>);
pub utxo_ret: Mutex<Result<TxOut, chain::AccessError>>,
pub watched_txn: Mutex<HashSet<(Txid, Script)>>,
pub watched_outputs: Mutex<HashSet<(OutPoint, Script)>>,
+ expectations: Mutex<Option<VecDeque<OnRegisterOutput>>>,
}
impl TestChainSource {
utxo_ret: Mutex::new(Ok(TxOut { value: u64::max_value(), script_pubkey })),
watched_txn: Mutex::new(HashSet::new()),
watched_outputs: Mutex::new(HashSet::new()),
+ expectations: Mutex::new(None),
}
}
+
+ /// Sets an expectation that [`chain::Filter::register_output`] is called.
+ pub fn expect(&self, expectation: OnRegisterOutput) -> &Self {
+ self.expectations.lock().unwrap()
+ .get_or_insert_with(|| VecDeque::new())
+ .push_back(expectation);
+ self
+ }
}
impl chain::Access for TestChainSource {
self.watched_txn.lock().unwrap().insert((*txid, script_pubkey.clone()));
}
- fn register_output(&self, outpoint: &OutPoint, script_pubkey: &Script) {
- self.watched_outputs.lock().unwrap().insert((*outpoint, script_pubkey.clone()));
+ fn register_output(&self, output: WatchedOutput) -> Option<(usize, Transaction)> {
+ let dependent_tx = match &mut *self.expectations.lock().unwrap() {
+ None => None,
+ Some(expectations) => match expectations.pop_front() {
+ None => {
+ panic!("Unexpected register_output: {:?}",
+ (output.outpoint, output.script_pubkey));
+ },
+ Some(expectation) => {
+ assert_eq!(output.outpoint, expectation.outpoint());
+ assert_eq!(&output.script_pubkey, expectation.script_pubkey());
+ expectation.returns
+ },
+ },
+ };
+
+ self.watched_outputs.lock().unwrap().insert((output.outpoint, output.script_pubkey));
+ dependent_tx
+ }
+}
+
+impl Drop for TestChainSource {
+ fn drop(&mut self) {
+ if std::thread::panicking() {
+ return;
+ }
+
+ if let Some(expectations) = &*self.expectations.lock().unwrap() {
+ if !expectations.is_empty() {
+ panic!("Unsatisfied expectations: {:?}", expectations);
+ }
+ }
+ }
+}
+
+/// An expectation that [`chain::Filter::register_output`] was called with a transaction output and
+/// returns an optional dependent transaction that spends the output in the same block.
+pub struct OnRegisterOutput {
+ /// The transaction output to register.
+ pub with: TxOutReference,
+
+ /// A dependent transaction spending the output along with its position in the block.
+ pub returns: Option<(usize, Transaction)>,
+}
+
+/// A transaction output as identified by an index into a transaction's output list.
+pub struct TxOutReference(pub Transaction, pub usize);
+
+impl OnRegisterOutput {
+ fn outpoint(&self) -> OutPoint {
+ let txid = self.with.0.txid();
+ let index = self.with.1 as u16;
+ OutPoint { txid, index }
+ }
+
+ fn script_pubkey(&self) -> &Script {
+ let index = self.with.1;
+ &self.with.0.output[index].script_pubkey
+ }
+}
+
+impl std::fmt::Debug for OnRegisterOutput {
+ fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+ f.debug_struct("OnRegisterOutput")
+ .field("outpoint", &self.outpoint())
+ .field("script_pubkey", self.script_pubkey())
+ .finish()
}
}