on_holder_tx_csv: u16,
commitment_secrets: CounterpartyCommitmentSecrets,
+ /// The set of outpoints in each counterparty commitment transaction. We always need at least
+ /// the payment hash from `HTLCOutputInCommitment` to claim even a revoked commitment
+ /// transaction broadcast as we need to be able to construct the witness script in all cases.
counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
/// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
/// Nor can we figure out their commitment numbers without the commitment transaction they are
}
}
+/// Compares a broadcasted commitment transaction's HTLCs with those in the latest state,
+/// failing any HTLCs which didn't make it into the broadcasted commitment transaction back
+/// after ANTI_REORG_DELAY blocks.
+///
+/// We always compare against the set of HTLCs in counterparty commitment transactions, as those
+/// are the commitment transactions which are generated by us. The off-chain state machine in
+/// `Channel` will automatically resolve any HTLCs which were never included in a commitment
+/// transaction when it detects channel closure, but it is up to us to ensure any HTLCs which were
+/// included in a remote commitment transaction are failed back if they are not present in the
+/// broadcasted commitment transaction.
+///
+/// Specifically, the removal process for HTLCs in `Channel` is always based on the counterparty
+/// sending a `revoke_and_ack`, which causes us to clear `prev_counterparty_commitment_txid`. Thus,
+/// as long as we examine both the current counterparty commitment transaction and, if it hasn't
+/// been revoked yet, the previous one, we we will never "forget" to resolve an HTLC.
+macro_rules! fail_unbroadcast_htlcs {
+ ($self: expr, $commitment_tx_type: expr, $commitment_tx_conf_height: expr, $confirmed_htlcs_list: expr, $logger: expr) => { {
+ macro_rules! check_htlc_fails {
+ ($txid: expr, $commitment_tx: expr) => {
+ if let Some(ref latest_outpoints) = $self.counterparty_claimable_outpoints.get($txid) {
+ for &(ref htlc, ref source_option) in latest_outpoints.iter() {
+ if let &Some(ref source) = source_option {
+ // Check if the HTLC is present in the commitment transaction that was
+ // broadcast, but not if it was below the dust limit, which we should
+ // fail backwards immediately as there is no way for us to learn the
+ // payment_preimage.
+ // Note that if the dust limit were allowed to change between
+ // commitment transactions we'd want to be check whether *any*
+ // broadcastable commitment transaction has the HTLC in it, but it
+ // cannot currently change after channel initialization, so we don't
+ // need to here.
+ let confirmed_htlcs_iter: &mut Iterator<Item = (&HTLCOutputInCommitment, Option<&HTLCSource>)> = &mut $confirmed_htlcs_list;
+ let mut matched_htlc = false;
+ for (ref broadcast_htlc, ref broadcast_source) in confirmed_htlcs_iter {
+ if broadcast_htlc.transaction_output_index.is_some() && Some(&**source) == *broadcast_source {
+ matched_htlc = true;
+ break;
+ }
+ }
+ if matched_htlc { continue; }
+ $self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
+ if entry.height != $commitment_tx_conf_height { return true; }
+ match entry.event {
+ OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
+ *update_source != **source
+ },
+ _ => true,
+ }
+ });
+ let entry = OnchainEventEntry {
+ txid: *$txid,
+ height: $commitment_tx_conf_height,
+ event: OnchainEvent::HTLCUpdate {
+ source: (**source).clone(),
+ payment_hash: htlc.payment_hash.clone(),
+ onchain_value_satoshis: Some(htlc.amount_msat / 1000),
+ },
+ };
+ log_trace!($logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of {} commitment transaction, waiting for confirmation (at height {})",
+ log_bytes!(htlc.payment_hash.0), $commitment_tx, $commitment_tx_type, entry.confirmation_threshold());
+ $self.onchain_events_awaiting_threshold_conf.push(entry);
+ }
+ }
+ }
+ }
+ }
+ if let Some(ref txid) = $self.current_counterparty_commitment_txid {
+ check_htlc_fails!(txid, "current");
+ }
+ if let Some(ref txid) = $self.prev_counterparty_commitment_txid {
+ check_htlc_fails!(txid, "previous");
+ }
+ } }
+}
+
impl<Signer: Sign> ChannelMonitorImpl<Signer> {
/// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
/// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
}
self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
- macro_rules! check_htlc_fails {
- ($txid: expr, $commitment_tx: expr) => {
- if let Some(ref outpoints) = self.counterparty_claimable_outpoints.get($txid) {
- for &(ref htlc, ref source_option) in outpoints.iter() {
- if let &Some(ref source) = source_option {
- self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
- if entry.height != height { return true; }
- match entry.event {
- OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
- *update_source != **source
- },
- _ => true,
- }
- });
- let entry = OnchainEventEntry {
- txid: *$txid,
- height,
- event: OnchainEvent::HTLCUpdate {
- source: (**source).clone(),
- payment_hash: htlc.payment_hash.clone(),
- onchain_value_satoshis: Some(htlc.amount_msat / 1000),
- },
- };
- log_info!(logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of revoked counterparty commitment transaction, waiting for confirmation (at height {})", log_bytes!(htlc.payment_hash.0), $commitment_tx, entry.confirmation_threshold());
- self.onchain_events_awaiting_threshold_conf.push(entry);
- }
- }
- }
- }
- }
- if let Some(ref txid) = self.current_counterparty_commitment_txid {
- check_htlc_fails!(txid, "current");
- }
- if let Some(ref txid) = self.prev_counterparty_commitment_txid {
- check_htlc_fails!(txid, "counterparty");
- }
- // No need to check holder commitment txn, symmetric HTLCSource must be present as per-htlc data on counterparty commitment tx
+ fail_unbroadcast_htlcs!(self, "revoked counterparty", height, [].iter().map(|a| *a), logger);
}
} else if let Some(per_commitment_data) = per_commitment_option {
// While this isn't useful yet, there is a potential race where if a counterparty
self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
log_info!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
-
- macro_rules! check_htlc_fails {
- ($txid: expr, $commitment_tx: expr, $id: tt) => {
- if let Some(ref latest_outpoints) = self.counterparty_claimable_outpoints.get($txid) {
- $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
- if let &Some(ref source) = source_option {
- // Check if the HTLC is present in the commitment transaction that was
- // broadcast, but not if it was below the dust limit, which we should
- // fail backwards immediately as there is no way for us to learn the
- // payment_preimage.
- // Note that if the dust limit were allowed to change between
- // commitment transactions we'd want to be check whether *any*
- // broadcastable commitment transaction has the HTLC in it, but it
- // cannot currently change after channel initialization, so we don't
- // need to here.
- for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
- if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
- continue $id;
- }
- }
- log_trace!(logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of counterparty commitment transaction", log_bytes!(htlc.payment_hash.0), $commitment_tx);
- self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
- if entry.height != height { return true; }
- match entry.event {
- OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
- *update_source != **source
- },
- _ => true,
- }
- });
- self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
- txid: *$txid,
- height,
- event: OnchainEvent::HTLCUpdate {
- source: (**source).clone(),
- payment_hash: htlc.payment_hash.clone(),
- onchain_value_satoshis: Some(htlc.amount_msat / 1000),
- },
- });
- }
- }
- }
- }
- }
- if let Some(ref txid) = self.current_counterparty_commitment_txid {
- check_htlc_fails!(txid, "current", 'current_loop);
- }
- if let Some(ref txid) = self.prev_counterparty_commitment_txid {
- check_htlc_fails!(txid, "previous", 'prev_loop);
- }
+ fail_unbroadcast_htlcs!(self, "counterparty", height, per_commitment_data.iter().map(|(a, b)| (a, b.as_ref().map(|b| b.as_ref()))), logger);
let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs(commitment_number, commitment_txid, Some(tx));
for req in htlc_claim_reqs {
let res = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
let mut to_watch = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, tx);
append_onchain_update!(res, to_watch);
+ fail_unbroadcast_htlcs!(self, "latest holder", height, self.current_holder_commitment_tx.htlc_outputs.iter().map(|(a, _, c)| (a, c.as_ref())), logger);
} else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
if holder_tx.txid == commitment_txid {
is_holder_tx = true;
let res = self.get_broadcasted_holder_claims(holder_tx, height);
let mut to_watch = self.get_broadcasted_holder_watch_outputs(holder_tx, tx);
append_onchain_update!(res, to_watch);
- }
- }
-
- macro_rules! fail_dust_htlcs_after_threshold_conf {
- ($holder_tx: expr, $commitment_tx: expr) => {
- for &(ref htlc, _, ref source) in &$holder_tx.htlc_outputs {
- if htlc.transaction_output_index.is_none() {
- if let &Some(ref source) = source {
- self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
- if entry.height != height { return true; }
- match entry.event {
- OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
- update_source != source
- },
- _ => true,
- }
- });
- let entry = OnchainEventEntry {
- txid: commitment_txid,
- height,
- event: OnchainEvent::HTLCUpdate {
- source: source.clone(), payment_hash: htlc.payment_hash,
- onchain_value_satoshis: Some(htlc.amount_msat / 1000)
- },
- };
- log_trace!(logger, "Failing HTLC with payment_hash {} from {} holder commitment tx due to broadcast of transaction, waiting confirmation (at height{})",
- log_bytes!(htlc.payment_hash.0), $commitment_tx, entry.confirmation_threshold());
- self.onchain_events_awaiting_threshold_conf.push(entry);
- }
- }
- }
+ fail_unbroadcast_htlcs!(self, "previous holder", height, holder_tx.htlc_outputs.iter().map(|(a, _, c)| (a, c.as_ref())), logger);
}
}
if is_holder_tx {
- fail_dust_htlcs_after_threshold_conf!(self.current_holder_commitment_tx, "latest");
- if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
- fail_dust_htlcs_after_threshold_conf!(holder_tx, "previous");
- }
}
(claim_requests, (commitment_txid, watch_outputs))
--- /dev/null
+// This file is Copyright its original authors, visible in version control
+// history.
+//
+// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
+// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
+// You may not use this file except in accordance with one or both of these
+// licenses.
+
+//! Further functional tests which test blockchain reorganizations.
+
+use chain::channelmonitor::ANTI_REORG_DELAY;
+use ln::{PaymentPreimage, PaymentHash};
+use ln::features::InitFeatures;
+use ln::msgs::{ChannelMessageHandler, HTLCFailChannelUpdate, ErrorAction};
+use util::events::{Event, MessageSendEvent, MessageSendEventsProvider};
+use routing::router::get_route;
+
+use bitcoin::hashes::sha256::Hash as Sha256;
+use bitcoin::hashes::Hash;
+
+use prelude::*;
+
+use ln::functional_test_utils::*;
+
+#[test]
+fn chanmon_fail_from_stale_commitment() {
+ // If we forward an HTLC to our counterparty, but we force-closed the channel before our
+ // counterparty provides us an updated commitment transaction, we'll end up with a commitment
+ // transaction that does not contain the HTLC which we attempted to forward. In this case, we
+ // need to wait `ANTI_REORG_DELAY` blocks and then fail back the HTLC as there is no way for us
+ // to learn the preimage and the confirmed commitment transaction paid us the value of the
+ // HTLC.
+ //
+ // However, previously, we did not do this, ignoring the HTLC entirely.
+ //
+ // This could lead to channel closure if the sender we received the HTLC from decides to go on
+ // chain to get their HTLC back before it times out.
+ //
+ // Here, we check exactly this case, forwarding a payment from A, through B, to C, before B
+ // broadcasts its latest commitment transaction, which should result in it eventually failing
+ // the HTLC back off-chain to A.
+ let chanmon_cfgs = create_chanmon_cfgs(3);
+ let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
+ let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
+ let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
+
+ create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
+ let (update_a, _, chan_id_2, _) = create_announced_chan_between_nodes(&nodes, 1, 2, InitFeatures::known(), InitFeatures::known());
+
+ let (route, payment_hash, _, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[2], 1_000_000);
+ nodes[0].node.send_payment(&route, payment_hash, &Some(payment_secret)).unwrap();
+ check_added_monitors!(nodes[0], 1);
+
+ let bs_txn = get_local_commitment_txn!(nodes[1], chan_id_2);
+
+ let updates = get_htlc_update_msgs!(nodes[0], nodes[1].node.get_our_node_id());
+ nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &updates.update_add_htlcs[0]);
+ commitment_signed_dance!(nodes[1], nodes[0], updates.commitment_signed, false);
+
+ expect_pending_htlcs_forwardable!(nodes[1]);
+ get_htlc_update_msgs!(nodes[1], nodes[2].node.get_our_node_id());
+ check_added_monitors!(nodes[1], 1);
+
+ // Don't bother delivering the new HTLC add/commits, instead confirming the pre-HTLC commitment
+ // transaction for nodes[1].
+ mine_transaction(&nodes[1], &bs_txn[0]);
+ check_added_monitors!(nodes[1], 1);
+ check_closed_broadcast!(nodes[1], true);
+ assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+
+ connect_blocks(&nodes[1], ANTI_REORG_DELAY - 1);
+ expect_pending_htlcs_forwardable!(nodes[1]);
+ check_added_monitors!(nodes[1], 1);
+ let fail_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
+
+ nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &fail_updates.update_fail_htlcs[0]);
+ commitment_signed_dance!(nodes[0], nodes[1], fail_updates.commitment_signed, true, true);
+ expect_payment_failed!(nodes[0], payment_hash, false);
+ expect_payment_failure_chan_update!(nodes[0], update_a.contents.short_channel_id, true);
+}
projects / rust-lightning / commitdiff