use bitcoin::hash_types::{BlockHash, WPubkeyHash};
use lightning::chain;
-use lightning::chain::chainmonitor::{ChannelMonitor, ChannelMonitorUpdateErr, MonitorEvent};
+ use lightning::chain::chainmonitor;
+use lightning::chain::channelmonitor;
+use lightning::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdateErr, MonitorEvent};
use lightning::chain::transaction::OutPoint;
use lightning::chain::chaininterface::{BroadcasterInterface, ConfirmationTarget, FeeEstimator};
use lightning::chain::keysinterface::{KeysInterface, InMemoryChannelKeys};
struct TestChainMonitor {
pub logger: Arc<dyn Logger>,
- pub chain_monitor: Arc<channelmonitor::ChainMonitor<EnforcingChannelKeys, Arc<dyn chain::Filter>, Arc<TestBroadcaster>, Arc<FuzzEstimator>, Arc<dyn Logger>>>,
+ pub chain_monitor: Arc<chainmonitor::ChainMonitor<EnforcingChannelKeys, Arc<dyn chain::Filter>, Arc<TestBroadcaster>, Arc<FuzzEstimator>, Arc<dyn Logger>>>,
- pub update_ret: Mutex<Result<(), chainmonitor::ChannelMonitorUpdateErr>>,
+ pub update_ret: Mutex<Result<(), channelmonitor::ChannelMonitorUpdateErr>>,
// If we reload a node with an old copy of ChannelMonitors, the ChannelManager deserialization
// logic will automatically force-close our channels for us (as we don't have an up-to-date
// monitor implying we are not able to punish misbehaving counterparties). Because this test
use lightning::chain;
use lightning::chain::chaininterface::{BroadcasterInterface, ConfirmationTarget, FeeEstimator};
- use lightning::chain::channelmonitor;
++use lightning::chain::chainmonitor;
use lightning::chain::transaction::OutPoint;
use lightning::chain::keysinterface::{InMemoryChannelKeys, KeysInterface};
-use lightning::chain::chainmonitor;
use lightning::ln::channelmanager::{ChannelManager, PaymentHash, PaymentPreimage, PaymentSecret};
use lightning::ln::peer_handler::{MessageHandler,PeerManager,SocketDescriptor};
use lightning::routing::router::get_route;
--- /dev/null
-//! The logic to monitor for on-chain transactions and create the relevant claim responses lives
-//! here.
+ // 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.
+
-//! ChannelMonitor objects are generated by ChannelManager in response to relevant
-//! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
-//! be made in responding to certain messages, see [`chain::Watch`] for more.
++//! Logic to connect off-chain channel management with on-chain transaction monitoring.
+ //!
-//! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
-//! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
-//! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
-//! security-domain-separated system design, you should consider having multiple paths for
-//! ChannelMonitors to get out of the HSM and onto monitoring devices.
++//! [`ChainMonitor`] is an implementation of [`chain::Watch`] used both to process blocks and to
++//! update [`ChannelMonitor`]s accordingly. If any on-chain events need further processing, it will
++//! make those available as [`MonitorEvent`]s to be consumed.
+ //!
-//! [`chain::Watch`]: ../../chain/trait.Watch.html
++//! `ChainMonitor` is parameterized by an optional chain source, which must implement the
++//! [`chain::Filter`] trait. This provides a mechanism to signal new relevant outputs back to light
++//! clients, such that transactions spending those outputs are included in block data.
+ //!
-use bitcoin::blockdata::transaction::{TxOut,Transaction};
-use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
-use bitcoin::blockdata::script::{Script, Builder};
-use bitcoin::blockdata::opcodes;
-use bitcoin::consensus::encode;
-
-use bitcoin::hashes::Hash;
-use bitcoin::hashes::sha256::Hash as Sha256;
-use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
++//! `ChainMonitor` may be used directly to monitor channels locally or as a part of a distributed
++//! setup to monitor channels remotely. In the latter case, a custom `chain::Watch` implementation
++//! would be responsible for routing each update to a remote server and for retrieving monitor
++//! events. The remote server would make use of `ChainMonitor` for block processing and for
++//! servicing `ChannelMonitor` updates from the client.
++//!
++//! [`ChainMonitor`]: struct.ChainMonitor.html
++//! [`chain::Filter`]: ../trait.Filter.html
++//! [`chain::Watch`]: ../trait.Watch.html
++//! [`ChannelMonitor`]: ../channelmonitor/struct.ChannelMonitor.html
++//! [`MonitorEvent`]: ../channelmonitor/enum.MonitorEvent.html
+
+ use bitcoin::blockdata::block::BlockHeader;
-use bitcoin::secp256k1::{Secp256k1,Signature};
-use bitcoin::secp256k1::key::{SecretKey,PublicKey};
-use bitcoin::secp256k1;
-
-use ln::msgs::DecodeError;
-use ln::chan_utils;
-use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, HolderCommitmentTransaction, HTLCType};
-use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
-use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
+
-use chain::keysinterface::{SpendableOutputDescriptor, ChannelKeys};
+ use chain;
+ use chain::Filter;
+ use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
++use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, MonitorEvent, MonitorUpdateError};
+ use chain::transaction::{OutPoint, TransactionData};
-use util::ser::{Readable, MaybeReadable, Writer, Writeable, U48};
-use util::{byte_utils, events};
++use chain::keysinterface::ChannelKeys;
+ use util::logger::Logger;
-use std::collections::{HashMap, HashSet, hash_map};
++use util::events;
+ use util::events::Event;
+
-use std::{cmp, mem};
++use std::collections::{HashMap, hash_map};
+ use std::sync::Mutex;
-use std::io::Error;
-
-/// An update generated by the underlying Channel itself which contains some new information the
-/// ChannelMonitor should be made aware of.
-#[cfg_attr(test, derive(PartialEq))]
-#[derive(Clone)]
-#[must_use]
-pub struct ChannelMonitorUpdate {
- pub(crate) updates: Vec<ChannelMonitorUpdateStep>,
- /// The sequence number of this update. Updates *must* be replayed in-order according to this
- /// sequence number (and updates may panic if they are not). The update_id values are strictly
- /// increasing and increase by one for each new update.
- ///
- /// This sequence number is also used to track up to which points updates which returned
- /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
- /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
- pub update_id: u64,
-}
-
-impl Writeable for ChannelMonitorUpdate {
- fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
- self.update_id.write(w)?;
- (self.updates.len() as u64).write(w)?;
- for update_step in self.updates.iter() {
- update_step.write(w)?;
- }
- Ok(())
- }
-}
-impl Readable for ChannelMonitorUpdate {
- fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
- let update_id: u64 = Readable::read(r)?;
- let len: u64 = Readable::read(r)?;
- let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<ChannelMonitorUpdateStep>()));
- for _ in 0..len {
- updates.push(Readable::read(r)?);
- }
- Ok(Self { update_id, updates })
- }
-}
-
-/// An error enum representing a failure to persist a channel monitor update.
-#[derive(Clone)]
-pub enum ChannelMonitorUpdateErr {
- /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
- /// our state failed, but is expected to succeed at some point in the future).
- ///
- /// Such a failure will "freeze" a channel, preventing us from revoking old states or
- /// submitting new commitment transactions to the counterparty. Once the update(s) which failed
- /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
- /// restore the channel to an operational state.
- ///
- /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
- /// you return a TemporaryFailure you must ensure that it is written to disk safely before
- /// writing out the latest ChannelManager state.
- ///
- /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
- /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
- /// to claim it on this channel) and those updates must be applied wherever they can be. At
- /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
- /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
- /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
- /// been "frozen".
- ///
- /// Note that even if updates made after TemporaryFailure succeed you must still call
- /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
- /// operation.
- ///
- /// Note that the update being processed here will not be replayed for you when you call
- /// ChannelManager::channel_monitor_updated, so you must store the update itself along
- /// with the persisted ChannelMonitor on your own local disk prior to returning a
- /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
- /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
- /// reload-time.
- ///
- /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
- /// remote location (with local copies persisted immediately), it is anticipated that all
- /// updates will return TemporaryFailure until the remote copies could be updated.
- TemporaryFailure,
- /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
- /// different watchtower and cannot update with all watchtowers that were previously informed
- /// of this channel).
- ///
- /// At reception of this error, ChannelManager will force-close the channel and return at
- /// least a final ChannelMonitorUpdate::ChannelForceClosed which must be delivered to at
- /// least one ChannelMonitor copy. Revocation secret MUST NOT be released and offchain channel
- /// update must be rejected.
- ///
- /// This failure may also signal a failure to update the local persisted copy of one of
- /// the channel monitor instance.
- ///
- /// Note that even when you fail a holder commitment transaction update, you must store the
- /// update to ensure you can claim from it in case of a duplicate copy of this ChannelMonitor
- /// broadcasts it (e.g distributed channel-monitor deployment)
- ///
- /// In case of distributed watchtowers deployment, the new version must be written to disk, as
- /// state may have been stored but rejected due to a block forcing a commitment broadcast. This
- /// storage is used to claim outputs of rejected state confirmed onchain by another watchtower,
- /// lagging behind on block processing.
- PermanentFailure,
-}
-
-/// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
-/// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
-/// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
-/// corrupted.
-/// Contains a human-readable error message.
-#[derive(Debug)]
-pub struct MonitorUpdateError(pub &'static str);
-
-/// An event to be processed by the ChannelManager.
-#[derive(PartialEq)]
-pub enum MonitorEvent {
- /// A monitor event containing an HTLCUpdate.
- HTLCEvent(HTLCUpdate),
-
- /// A monitor event that the Channel's commitment transaction was broadcasted.
- CommitmentTxBroadcasted(OutPoint),
-}
-
-/// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
-/// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
-/// preimage claim backward will lead to loss of funds.
-///
-/// [`chain::Watch`]: ../../chain/trait.Watch.html
-#[derive(Clone, PartialEq)]
-pub struct HTLCUpdate {
- pub(crate) payment_hash: PaymentHash,
- pub(crate) payment_preimage: Option<PaymentPreimage>,
- pub(crate) source: HTLCSource
-}
-impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
+ use std::ops::Deref;
-/// or used independently to monitor channels remotely.
+
+ /// An implementation of [`chain::Watch`] for monitoring channels.
+ ///
+ /// Connected and disconnected blocks must be provided to `ChainMonitor` as documented by
+ /// [`chain::Watch`]. May be used in conjunction with [`ChannelManager`] to monitor channels locally
-/// [`chain::Watch`]: ../../chain/trait.Watch.html
-/// [`ChannelManager`]: ../channelmanager/struct.ChannelManager.html
++/// or used independently to monitor channels remotely. See the [module-level documentation] for
++/// details.
+ ///
- /// [`ChannelMonitor::block_connected`]: struct.ChannelMonitor.html#method.block_connected
- /// [`chain::Watch::release_pending_monitor_events`]: ../../chain/trait.Watch.html#tymethod.release_pending_monitor_events
- /// [`chain::Filter`]: ../../chain/trait.Filter.html
++/// [`chain::Watch`]: ../trait.Watch.html
++/// [`ChannelManager`]: ../../ln/channelmanager/struct.ChannelManager.html
++/// [module-level documentation]: index.html
+ pub struct ChainMonitor<ChanSigner: ChannelKeys, C: Deref, T: Deref, F: Deref, L: Deref>
+ where C::Target: chain::Filter,
+ T::Target: BroadcasterInterface,
+ F::Target: FeeEstimator,
+ L::Target: Logger,
+ {
+ /// The monitors
+ pub monitors: Mutex<HashMap<OutPoint, ChannelMonitor<ChanSigner>>>,
+ chain_source: Option<C>,
+ broadcaster: T,
+ logger: L,
+ fee_estimator: F
+ }
+
+ impl<ChanSigner: ChannelKeys, C: Deref, T: Deref, F: Deref, L: Deref> ChainMonitor<ChanSigner, C, T, F, L>
+ where C::Target: chain::Filter,
+ T::Target: BroadcasterInterface,
+ F::Target: FeeEstimator,
+ L::Target: Logger,
+ {
+ /// Dispatches to per-channel monitors, which are responsible for updating their on-chain view
+ /// of a channel and reacting accordingly based on transactions in the connected block. See
+ /// [`ChannelMonitor::block_connected`] for details. Any HTLCs that were resolved on chain will
+ /// be returned by [`chain::Watch::release_pending_monitor_events`].
+ ///
+ /// Calls back to [`chain::Filter`] if any monitor indicated new outputs to watch, returning
+ /// `true` if so. Subsequent calls must not exclude any transactions matching the new outputs
+ /// nor any in-block descendants of such transactions. It is not necessary to re-fetch the block
+ /// to obtain updated `txdata`.
+ ///
- /// [`ChannelMonitor::block_disconnected`]: struct.ChannelMonitor.html#method.block_disconnected
++ /// [`ChannelMonitor::block_connected`]: ../channelmonitor/struct.ChannelMonitor.html#method.block_connected
++ /// [`chain::Watch::release_pending_monitor_events`]: ../trait.Watch.html#tymethod.release_pending_monitor_events
++ /// [`chain::Filter`]: ../trait.Filter.html
+ pub fn block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) -> bool {
+ let mut has_new_outputs_to_watch = false;
+ {
+ let mut monitors = self.monitors.lock().unwrap();
+ for monitor in monitors.values_mut() {
+ let mut txn_outputs = monitor.block_connected(header, txdata, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
+ has_new_outputs_to_watch |= !txn_outputs.is_empty();
+
+ if let Some(ref chain_source) = self.chain_source {
+ for (txid, outputs) in txn_outputs.drain(..) {
+ for (idx, output) in outputs.iter().enumerate() {
+ chain_source.register_output(&OutPoint { txid, index: idx as u16 }, &output.script_pubkey);
+ }
+ }
+ }
+ }
+ }
+ has_new_outputs_to_watch
+ }
+
+ /// Dispatches to per-channel monitors, which are responsible for updating their on-chain view
+ /// of a channel based on the disconnected block. See [`ChannelMonitor::block_disconnected`] for
+ /// details.
+ ///
- /// [`chain::Filter`]: ../../chain/trait.Filter.html
++ /// [`ChannelMonitor::block_disconnected`]: ../channelmonitor/struct.ChannelMonitor.html#method.block_disconnected
+ pub fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
+ let mut monitors = self.monitors.lock().unwrap();
+ for monitor in monitors.values_mut() {
+ monitor.block_disconnected(header, disconnected_height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
+ }
+ }
+
+ /// Creates a new `ChainMonitor` used to watch on-chain activity pertaining to channels.
+ ///
+ /// When an optional chain source implementing [`chain::Filter`] is provided, the chain monitor
+ /// will call back to it indicating transactions and outputs of interest. This allows clients to
+ /// pre-filter blocks or only fetch blocks matching a compact filter. Otherwise, clients may
+ /// always need to fetch full blocks absent another means for determining which blocks contain
+ /// transactions relevant to the watched channels.
+ ///
- /// [`chain::Filter`]: ../../chain/trait.Filter.html
++ /// [`chain::Filter`]: ../trait.Filter.html
+ pub fn new(chain_source: Option<C>, broadcaster: T, logger: L, feeest: F) -> Self {
+ Self {
+ monitors: Mutex::new(HashMap::new()),
+ chain_source,
+ broadcaster,
+ logger,
+ fee_estimator: feeest,
+ }
+ }
+
+ /// Adds the monitor that watches the channel referred to by the given outpoint.
+ ///
+ /// Calls back to [`chain::Filter`] with the funding transaction and outputs to watch.
+ ///
-
-/// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
-/// instead claiming it in its own individual transaction.
-pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
-/// If an HTLC expires within this many blocks, force-close the channel to broadcast the
-/// HTLC-Success transaction.
-/// In other words, this is an upper bound on how many blocks we think it can take us to get a
-/// transaction confirmed (and we use it in a few more, equivalent, places).
-pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
-/// Number of blocks by which point we expect our counterparty to have seen new blocks on the
-/// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
-/// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
-/// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
-/// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
-/// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
-/// due to expiration but increase the cost of funds being locked longuer in case of failure.
-/// This delay also cover a low-power peer being slow to process blocks and so being behind us on
-/// accurate block height.
-/// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
-/// with at worst this delay, so we are not only using this value as a mercy for them but also
-/// us as a safeguard to delay with enough time.
-pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
-/// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
-/// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
-/// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
-/// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
-/// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
-/// keeping bumping another claim tx to solve the outpoint.
-pub(crate) const ANTI_REORG_DELAY: u32 = 6;
-/// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
-/// refuse to accept a new HTLC.
-///
-/// This is used for a few separate purposes:
-/// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
-/// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
-/// fail this HTLC,
-/// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
-/// condition with the above), we will fail this HTLC without telling the user we received it,
-/// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
-/// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
-///
-/// (1) is all about protecting us - we need enough time to update the channel state before we hit
-/// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
-///
-/// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
-/// in a race condition between the user connecting a block (which would fail it) and the user
-/// providing us the preimage (which would claim it).
-///
-/// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
-/// end up force-closing the channel on us to claim it.
-pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
-
-#[derive(Clone, PartialEq)]
-struct HolderSignedTx {
- /// txid of the transaction in tx, just used to make comparison faster
- txid: Txid,
- revocation_key: PublicKey,
- a_htlc_key: PublicKey,
- b_htlc_key: PublicKey,
- delayed_payment_key: PublicKey,
- per_commitment_point: PublicKey,
- feerate_per_kw: u32,
- htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
-}
-
-/// We use this to track counterparty commitment transactions and htlcs outputs and
-/// use it to generate any justice or 2nd-stage preimage/timeout transactions.
-#[derive(PartialEq)]
-struct CounterpartyCommitmentTransaction {
- counterparty_delayed_payment_base_key: PublicKey,
- counterparty_htlc_base_key: PublicKey,
- on_counterparty_tx_csv: u16,
- per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
-}
-
-impl Writeable for CounterpartyCommitmentTransaction {
- fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
- self.counterparty_delayed_payment_base_key.write(w)?;
- self.counterparty_htlc_base_key.write(w)?;
- w.write_all(&byte_utils::be16_to_array(self.on_counterparty_tx_csv))?;
- w.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?;
- for (ref txid, ref htlcs) in self.per_htlc.iter() {
- w.write_all(&txid[..])?;
- w.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
- for &ref htlc in htlcs.iter() {
- htlc.write(w)?;
- }
- }
- Ok(())
- }
-}
-impl Readable for CounterpartyCommitmentTransaction {
- fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
- let counterparty_commitment_transaction = {
- let counterparty_delayed_payment_base_key = Readable::read(r)?;
- let counterparty_htlc_base_key = Readable::read(r)?;
- let on_counterparty_tx_csv: u16 = Readable::read(r)?;
- let per_htlc_len: u64 = Readable::read(r)?;
- let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
- for _ in 0..per_htlc_len {
- let txid: Txid = Readable::read(r)?;
- let htlcs_count: u64 = Readable::read(r)?;
- let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
- for _ in 0..htlcs_count {
- let htlc = Readable::read(r)?;
- htlcs.push(htlc);
- }
- if let Some(_) = per_htlc.insert(txid, htlcs) {
- return Err(DecodeError::InvalidValue);
- }
- }
- CounterpartyCommitmentTransaction {
- counterparty_delayed_payment_base_key,
- counterparty_htlc_base_key,
- on_counterparty_tx_csv,
- per_htlc,
- }
- };
- Ok(counterparty_commitment_transaction)
- }
-}
-
-/// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
-/// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
-/// a new bumped one in case of lenghty confirmation delay
-#[derive(Clone, PartialEq)]
-pub(crate) enum InputMaterial {
- Revoked {
- per_commitment_point: PublicKey,
- counterparty_delayed_payment_base_key: PublicKey,
- counterparty_htlc_base_key: PublicKey,
- per_commitment_key: SecretKey,
- input_descriptor: InputDescriptors,
- amount: u64,
- htlc: Option<HTLCOutputInCommitment>,
- on_counterparty_tx_csv: u16,
- },
- CounterpartyHTLC {
- per_commitment_point: PublicKey,
- counterparty_delayed_payment_base_key: PublicKey,
- counterparty_htlc_base_key: PublicKey,
- preimage: Option<PaymentPreimage>,
- htlc: HTLCOutputInCommitment
- },
- HolderHTLC {
- preimage: Option<PaymentPreimage>,
- amount: u64,
- },
- Funding {
- funding_redeemscript: Script,
- }
-}
-
-impl Writeable for InputMaterial {
- fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
- match self {
- &InputMaterial::Revoked { ref per_commitment_point, ref counterparty_delayed_payment_base_key, ref counterparty_htlc_base_key, ref per_commitment_key, ref input_descriptor, ref amount, ref htlc, ref on_counterparty_tx_csv} => {
- writer.write_all(&[0; 1])?;
- per_commitment_point.write(writer)?;
- counterparty_delayed_payment_base_key.write(writer)?;
- counterparty_htlc_base_key.write(writer)?;
- writer.write_all(&per_commitment_key[..])?;
- input_descriptor.write(writer)?;
- writer.write_all(&byte_utils::be64_to_array(*amount))?;
- htlc.write(writer)?;
- on_counterparty_tx_csv.write(writer)?;
- },
- &InputMaterial::CounterpartyHTLC { ref per_commitment_point, ref counterparty_delayed_payment_base_key, ref counterparty_htlc_base_key, ref preimage, ref htlc} => {
- writer.write_all(&[1; 1])?;
- per_commitment_point.write(writer)?;
- counterparty_delayed_payment_base_key.write(writer)?;
- counterparty_htlc_base_key.write(writer)?;
- preimage.write(writer)?;
- htlc.write(writer)?;
- },
- &InputMaterial::HolderHTLC { ref preimage, ref amount } => {
- writer.write_all(&[2; 1])?;
- preimage.write(writer)?;
- writer.write_all(&byte_utils::be64_to_array(*amount))?;
- },
- &InputMaterial::Funding { ref funding_redeemscript } => {
- writer.write_all(&[3; 1])?;
- funding_redeemscript.write(writer)?;
- }
- }
- Ok(())
- }
-}
-
-impl Readable for InputMaterial {
- fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
- let input_material = match <u8 as Readable>::read(reader)? {
- 0 => {
- let per_commitment_point = Readable::read(reader)?;
- let counterparty_delayed_payment_base_key = Readable::read(reader)?;
- let counterparty_htlc_base_key = Readable::read(reader)?;
- let per_commitment_key = Readable::read(reader)?;
- let input_descriptor = Readable::read(reader)?;
- let amount = Readable::read(reader)?;
- let htlc = Readable::read(reader)?;
- let on_counterparty_tx_csv = Readable::read(reader)?;
- InputMaterial::Revoked {
- per_commitment_point,
- counterparty_delayed_payment_base_key,
- counterparty_htlc_base_key,
- per_commitment_key,
- input_descriptor,
- amount,
- htlc,
- on_counterparty_tx_csv
- }
- },
- 1 => {
- let per_commitment_point = Readable::read(reader)?;
- let counterparty_delayed_payment_base_key = Readable::read(reader)?;
- let counterparty_htlc_base_key = Readable::read(reader)?;
- let preimage = Readable::read(reader)?;
- let htlc = Readable::read(reader)?;
- InputMaterial::CounterpartyHTLC {
- per_commitment_point,
- counterparty_delayed_payment_base_key,
- counterparty_htlc_base_key,
- preimage,
- htlc
- }
- },
- 2 => {
- let preimage = Readable::read(reader)?;
- let amount = Readable::read(reader)?;
- InputMaterial::HolderHTLC {
- preimage,
- amount,
- }
- },
- 3 => {
- InputMaterial::Funding {
- funding_redeemscript: Readable::read(reader)?,
- }
- }
- _ => return Err(DecodeError::InvalidValue),
- };
- Ok(input_material)
- }
-}
-
-/// ClaimRequest is a descriptor structure to communicate between detection
-/// and reaction module. They are generated by ChannelMonitor while parsing
-/// onchain txn leaked from a channel and handed over to OnchainTxHandler which
-/// is responsible for opportunistic aggregation, selecting and enforcing
-/// bumping logic, building and signing transactions.
-pub(crate) struct ClaimRequest {
- // Block height before which claiming is exclusive to one party,
- // after reaching it, claiming may be contentious.
- pub(crate) absolute_timelock: u32,
- // Timeout tx must have nLocktime set which means aggregating multiple
- // ones must take the higher nLocktime among them to satisfy all of them.
- // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
- // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
- // Do simplify we mark them as non-aggregable.
- pub(crate) aggregable: bool,
- // Basic bitcoin outpoint (txid, vout)
- pub(crate) outpoint: BitcoinOutPoint,
- // Following outpoint type, set of data needed to generate transaction digest
- // and satisfy witness program.
- pub(crate) witness_data: InputMaterial
-}
-
-/// 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(Clone, PartialEq)]
-enum OnchainEvent {
- /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
- /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
- /// only win from it, so it's never an OnchainEvent
- HTLCUpdate {
- htlc_update: (HTLCSource, PaymentHash),
- },
- MaturingOutput {
- descriptor: SpendableOutputDescriptor,
- },
-}
-
-const SERIALIZATION_VERSION: u8 = 1;
-const MIN_SERIALIZATION_VERSION: u8 = 1;
-
-#[cfg_attr(test, derive(PartialEq))]
-#[derive(Clone)]
-pub(crate) enum ChannelMonitorUpdateStep {
- LatestHolderCommitmentTXInfo {
- commitment_tx: HolderCommitmentTransaction,
- htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
- },
- LatestCounterpartyCommitmentTXInfo {
- unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
- htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
- commitment_number: u64,
- their_revocation_point: PublicKey,
- },
- PaymentPreimage {
- payment_preimage: PaymentPreimage,
- },
- CommitmentSecret {
- idx: u64,
- secret: [u8; 32],
- },
- /// Used to indicate that the no future updates will occur, and likely that the latest holder
- /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
- ChannelForceClosed {
- /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
- /// think we've fallen behind!
- should_broadcast: bool,
- },
-}
-
-impl Writeable for ChannelMonitorUpdateStep {
- fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
- match self {
- &ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
- 0u8.write(w)?;
- commitment_tx.write(w)?;
- (htlc_outputs.len() as u64).write(w)?;
- for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
- output.write(w)?;
- signature.write(w)?;
- source.write(w)?;
- }
- }
- &ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
- 1u8.write(w)?;
- unsigned_commitment_tx.write(w)?;
- commitment_number.write(w)?;
- their_revocation_point.write(w)?;
- (htlc_outputs.len() as u64).write(w)?;
- for &(ref output, ref source) in htlc_outputs.iter() {
- output.write(w)?;
- source.as_ref().map(|b| b.as_ref()).write(w)?;
- }
- },
- &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
- 2u8.write(w)?;
- payment_preimage.write(w)?;
- },
- &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
- 3u8.write(w)?;
- idx.write(w)?;
- secret.write(w)?;
- },
- &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
- 4u8.write(w)?;
- should_broadcast.write(w)?;
- },
- }
- Ok(())
- }
-}
-impl Readable for ChannelMonitorUpdateStep {
- fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
- match Readable::read(r)? {
- 0u8 => {
- Ok(ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
- commitment_tx: Readable::read(r)?,
- htlc_outputs: {
- let len: u64 = Readable::read(r)?;
- let mut res = Vec::new();
- for _ in 0..len {
- res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
- }
- res
- },
- })
- },
- 1u8 => {
- Ok(ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
- unsigned_commitment_tx: Readable::read(r)?,
- commitment_number: Readable::read(r)?,
- their_revocation_point: Readable::read(r)?,
- htlc_outputs: {
- let len: u64 = Readable::read(r)?;
- let mut res = Vec::new();
- for _ in 0..len {
- res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
- }
- res
- },
- })
- },
- 2u8 => {
- Ok(ChannelMonitorUpdateStep::PaymentPreimage {
- payment_preimage: Readable::read(r)?,
- })
- },
- 3u8 => {
- Ok(ChannelMonitorUpdateStep::CommitmentSecret {
- idx: Readable::read(r)?,
- secret: Readable::read(r)?,
- })
- },
- 4u8 => {
- Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
- should_broadcast: Readable::read(r)?
- })
- },
- _ => Err(DecodeError::InvalidValue),
- }
- }
-}
-
-/// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
-/// on-chain transactions to ensure no loss of funds occurs.
-///
-/// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
-/// information and are actively monitoring the chain.
-///
-/// Pending Events or updated HTLCs which have not yet been read out by
-/// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
-/// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
-/// gotten are fully handled before re-serializing the new state.
-pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
- latest_update_id: u64,
- commitment_transaction_number_obscure_factor: u64,
-
- destination_script: Script,
- broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
- counterparty_payment_script: Script,
- shutdown_script: Script,
-
- keys: ChanSigner,
- funding_info: (OutPoint, Script),
- current_counterparty_commitment_txid: Option<Txid>,
- prev_counterparty_commitment_txid: Option<Txid>,
-
- counterparty_tx_cache: CounterpartyCommitmentTransaction,
- funding_redeemscript: Script,
- channel_value_satoshis: u64,
- // first is the idx of the first of the two revocation points
- their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
-
- on_holder_tx_csv: u16,
-
- commitment_secrets: CounterpartyCommitmentSecrets,
- 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
- /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
- /// commitment transactions which we find on-chain, mapping them to the commitment number which
- /// can be used to derive the revocation key and claim the transactions.
- counterparty_commitment_txn_on_chain: HashMap<Txid, (u64, Vec<Script>)>,
- /// Cache used to make pruning of payment_preimages faster.
- /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
- /// counterparty transactions (ie should remain pretty small).
- /// Serialized to disk but should generally not be sent to Watchtowers.
- counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
-
- // We store two holder commitment transactions to avoid any race conditions where we may update
- // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
- // various monitors for one channel being out of sync, and us broadcasting a holder
- // transaction for which we have deleted claim information on some watchtowers.
- prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
- current_holder_commitment_tx: HolderSignedTx,
-
- // Used just for ChannelManager to make sure it has the latest channel data during
- // deserialization
- current_counterparty_commitment_number: u64,
- // Used just for ChannelManager to make sure it has the latest channel data during
- // deserialization
- current_holder_commitment_number: u64,
-
- payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
-
- pending_monitor_events: Vec<MonitorEvent>,
- pending_events: Vec<Event>,
-
- // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
- // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
- // actions when we receive a block with given height. Actions depend on OnchainEvent type.
- onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
-
- // If we get serialized out and re-read, we need to make sure that the chain monitoring
- // interface knows about the TXOs that we want to be notified of spends of. We could probably
- // be smart and derive them from the above storage fields, but its much simpler and more
- // Obviously Correct (tm) if we just keep track of them explicitly.
- outputs_to_watch: HashMap<Txid, Vec<Script>>,
-
- #[cfg(test)]
- pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
- #[cfg(not(test))]
- onchain_tx_handler: OnchainTxHandler<ChanSigner>,
-
- // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
- // channel has been force-closed. After this is set, no further holder commitment transaction
- // updates may occur, and we panic!() if one is provided.
- lockdown_from_offchain: bool,
-
- // Set once we've signed a holder commitment transaction and handed it over to our
- // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
- // may occur, and we fail any such monitor updates.
- //
- // In case of update rejection due to a locally already signed commitment transaction, we
- // nevertheless store update content to track in case of concurrent broadcast by another
- // remote monitor out-of-order with regards to the block view.
- holder_tx_signed: bool,
-
- // We simply modify last_block_hash in Channel's block_connected so that serialization is
- // consistent but hopefully the users' copy handles block_connected in a consistent way.
- // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
- // their last_block_hash from its state and not based on updated copies that didn't run through
- // the full block_connected).
- last_block_hash: BlockHash,
- secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
-}
-
-#[cfg(any(test, feature = "fuzztarget"))]
-/// Used only in testing and fuzztarget to check serialization roundtrips don't change the
-/// underlying object
-impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
- fn eq(&self, other: &Self) -> bool {
- if self.latest_update_id != other.latest_update_id ||
- self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
- self.destination_script != other.destination_script ||
- self.broadcasted_holder_revokable_script != other.broadcasted_holder_revokable_script ||
- self.counterparty_payment_script != other.counterparty_payment_script ||
- self.keys.pubkeys() != other.keys.pubkeys() ||
- self.funding_info != other.funding_info ||
- self.current_counterparty_commitment_txid != other.current_counterparty_commitment_txid ||
- self.prev_counterparty_commitment_txid != other.prev_counterparty_commitment_txid ||
- self.counterparty_tx_cache != other.counterparty_tx_cache ||
- self.funding_redeemscript != other.funding_redeemscript ||
- self.channel_value_satoshis != other.channel_value_satoshis ||
- self.their_cur_revocation_points != other.their_cur_revocation_points ||
- self.on_holder_tx_csv != other.on_holder_tx_csv ||
- self.commitment_secrets != other.commitment_secrets ||
- self.counterparty_claimable_outpoints != other.counterparty_claimable_outpoints ||
- self.counterparty_commitment_txn_on_chain != other.counterparty_commitment_txn_on_chain ||
- self.counterparty_hash_commitment_number != other.counterparty_hash_commitment_number ||
- self.prev_holder_signed_commitment_tx != other.prev_holder_signed_commitment_tx ||
- self.current_counterparty_commitment_number != other.current_counterparty_commitment_number ||
- self.current_holder_commitment_number != other.current_holder_commitment_number ||
- self.current_holder_commitment_tx != other.current_holder_commitment_tx ||
- self.payment_preimages != other.payment_preimages ||
- self.pending_monitor_events != other.pending_monitor_events ||
- self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
- self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
- self.outputs_to_watch != other.outputs_to_watch ||
- self.lockdown_from_offchain != other.lockdown_from_offchain ||
- self.holder_tx_signed != other.holder_tx_signed
- {
- false
- } else {
- true
- }
- }
-}
-
-impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
- /// Writes this monitor into the given writer, suitable for writing to disk.
- ///
- /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
- /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
- /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
- /// returned block hash and the the current chain and then reconnecting blocks to get to the
- /// best chain) upon deserializing the object!
- pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
- //TODO: We still write out all the serialization here manually instead of using the fancy
- //serialization framework we have, we should migrate things over to it.
- writer.write_all(&[SERIALIZATION_VERSION; 1])?;
- writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
-
- self.latest_update_id.write(writer)?;
-
- // Set in initial Channel-object creation, so should always be set by now:
- U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
-
- self.destination_script.write(writer)?;
- if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
- writer.write_all(&[0; 1])?;
- broadcasted_holder_revokable_script.0.write(writer)?;
- broadcasted_holder_revokable_script.1.write(writer)?;
- broadcasted_holder_revokable_script.2.write(writer)?;
- } else {
- writer.write_all(&[1; 1])?;
- }
-
- self.counterparty_payment_script.write(writer)?;
- self.shutdown_script.write(writer)?;
-
- self.keys.write(writer)?;
- writer.write_all(&self.funding_info.0.txid[..])?;
- writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
- self.funding_info.1.write(writer)?;
- self.current_counterparty_commitment_txid.write(writer)?;
- self.prev_counterparty_commitment_txid.write(writer)?;
-
- self.counterparty_tx_cache.write(writer)?;
- self.funding_redeemscript.write(writer)?;
- self.channel_value_satoshis.write(writer)?;
-
- match self.their_cur_revocation_points {
- Some((idx, pubkey, second_option)) => {
- writer.write_all(&byte_utils::be48_to_array(idx))?;
- writer.write_all(&pubkey.serialize())?;
- match second_option {
- Some(second_pubkey) => {
- writer.write_all(&second_pubkey.serialize())?;
- },
- None => {
- writer.write_all(&[0; 33])?;
- },
- }
- },
- None => {
- writer.write_all(&byte_utils::be48_to_array(0))?;
- },
- }
-
- writer.write_all(&byte_utils::be16_to_array(self.on_holder_tx_csv))?;
-
- self.commitment_secrets.write(writer)?;
-
- macro_rules! serialize_htlc_in_commitment {
- ($htlc_output: expr) => {
- writer.write_all(&[$htlc_output.offered as u8; 1])?;
- writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
- writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
- writer.write_all(&$htlc_output.payment_hash.0[..])?;
- $htlc_output.transaction_output_index.write(writer)?;
- }
- }
-
- writer.write_all(&byte_utils::be64_to_array(self.counterparty_claimable_outpoints.len() as u64))?;
- for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
- writer.write_all(&txid[..])?;
- writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
- for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
- serialize_htlc_in_commitment!(htlc_output);
- htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
- }
- }
-
- writer.write_all(&byte_utils::be64_to_array(self.counterparty_commitment_txn_on_chain.len() as u64))?;
- for (ref txid, &(commitment_number, ref txouts)) in self.counterparty_commitment_txn_on_chain.iter() {
- writer.write_all(&txid[..])?;
- writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
- (txouts.len() as u64).write(writer)?;
- for script in txouts.iter() {
- script.write(writer)?;
- }
- }
-
- writer.write_all(&byte_utils::be64_to_array(self.counterparty_hash_commitment_number.len() as u64))?;
- for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
- writer.write_all(&payment_hash.0[..])?;
- writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
- }
-
- macro_rules! serialize_holder_tx {
- ($holder_tx: expr) => {
- $holder_tx.txid.write(writer)?;
- writer.write_all(&$holder_tx.revocation_key.serialize())?;
- writer.write_all(&$holder_tx.a_htlc_key.serialize())?;
- writer.write_all(&$holder_tx.b_htlc_key.serialize())?;
- writer.write_all(&$holder_tx.delayed_payment_key.serialize())?;
- writer.write_all(&$holder_tx.per_commitment_point.serialize())?;
-
- writer.write_all(&byte_utils::be32_to_array($holder_tx.feerate_per_kw))?;
- writer.write_all(&byte_utils::be64_to_array($holder_tx.htlc_outputs.len() as u64))?;
- for &(ref htlc_output, ref sig, ref htlc_source) in $holder_tx.htlc_outputs.iter() {
- serialize_htlc_in_commitment!(htlc_output);
- if let &Some(ref their_sig) = sig {
- 1u8.write(writer)?;
- writer.write_all(&their_sig.serialize_compact())?;
- } else {
- 0u8.write(writer)?;
- }
- htlc_source.write(writer)?;
- }
- }
- }
-
- if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
- writer.write_all(&[1; 1])?;
- serialize_holder_tx!(prev_holder_tx);
- } else {
- writer.write_all(&[0; 1])?;
- }
-
- serialize_holder_tx!(self.current_holder_commitment_tx);
-
- writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
- writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
-
- writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
- for payment_preimage in self.payment_preimages.values() {
- writer.write_all(&payment_preimage.0[..])?;
- }
-
- writer.write_all(&byte_utils::be64_to_array(self.pending_monitor_events.len() as u64))?;
- for event in self.pending_monitor_events.iter() {
- match event {
- MonitorEvent::HTLCEvent(upd) => {
- 0u8.write(writer)?;
- upd.write(writer)?;
- },
- MonitorEvent::CommitmentTxBroadcasted(_) => 1u8.write(writer)?
- }
- }
-
- writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
- for event in self.pending_events.iter() {
- event.write(writer)?;
- }
-
- self.last_block_hash.write(writer)?;
-
- writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
- for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
- writer.write_all(&byte_utils::be32_to_array(**target))?;
- writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
- for ev in events.iter() {
- match *ev {
- OnchainEvent::HTLCUpdate { ref htlc_update } => {
- 0u8.write(writer)?;
- htlc_update.0.write(writer)?;
- htlc_update.1.write(writer)?;
- },
- OnchainEvent::MaturingOutput { ref descriptor } => {
- 1u8.write(writer)?;
- descriptor.write(writer)?;
- },
- }
- }
- }
-
- (self.outputs_to_watch.len() as u64).write(writer)?;
- for (txid, output_scripts) in self.outputs_to_watch.iter() {
- txid.write(writer)?;
- (output_scripts.len() as u64).write(writer)?;
- for script in output_scripts.iter() {
- script.write(writer)?;
- }
- }
- self.onchain_tx_handler.write(writer)?;
-
- self.lockdown_from_offchain.write(writer)?;
- self.holder_tx_signed.write(writer)?;
-
- Ok(())
- }
-}
-
-impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
- pub(crate) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
- on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
- counterparty_htlc_base_key: &PublicKey, counterparty_delayed_payment_base_key: &PublicKey,
- on_holder_tx_csv: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
- commitment_transaction_number_obscure_factor: u64,
- initial_holder_commitment_tx: HolderCommitmentTransaction) -> ChannelMonitor<ChanSigner> {
-
- assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
- let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
- let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
- let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
- let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
-
- let counterparty_tx_cache = CounterpartyCommitmentTransaction { counterparty_delayed_payment_base_key: *counterparty_delayed_payment_base_key, counterparty_htlc_base_key: *counterparty_htlc_base_key, on_counterparty_tx_csv, per_htlc: HashMap::new() };
-
- let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys.clone(), on_holder_tx_csv);
-
- let holder_tx_sequence = initial_holder_commitment_tx.unsigned_tx.input[0].sequence as u64;
- let holder_tx_locktime = initial_holder_commitment_tx.unsigned_tx.lock_time as u64;
- let holder_commitment_tx = HolderSignedTx {
- txid: initial_holder_commitment_tx.txid(),
- revocation_key: initial_holder_commitment_tx.keys.revocation_key,
- a_htlc_key: initial_holder_commitment_tx.keys.broadcaster_htlc_key,
- b_htlc_key: initial_holder_commitment_tx.keys.countersignatory_htlc_key,
- delayed_payment_key: initial_holder_commitment_tx.keys.broadcaster_delayed_payment_key,
- per_commitment_point: initial_holder_commitment_tx.keys.per_commitment_point,
- feerate_per_kw: initial_holder_commitment_tx.feerate_per_kw,
- htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
- };
- onchain_tx_handler.provide_latest_holder_tx(initial_holder_commitment_tx);
-
- let mut outputs_to_watch = HashMap::new();
- outputs_to_watch.insert(funding_info.0.txid, vec![funding_info.1.clone()]);
-
- ChannelMonitor {
- latest_update_id: 0,
- commitment_transaction_number_obscure_factor,
-
- destination_script: destination_script.clone(),
- broadcasted_holder_revokable_script: None,
- counterparty_payment_script,
- shutdown_script,
-
- keys,
- funding_info,
- current_counterparty_commitment_txid: None,
- prev_counterparty_commitment_txid: None,
-
- counterparty_tx_cache,
- funding_redeemscript,
- channel_value_satoshis: channel_value_satoshis,
- their_cur_revocation_points: None,
-
- on_holder_tx_csv,
-
- 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: 0xffff_ffff_ffff - ((((holder_tx_sequence & 0xffffff) << 3*8) | (holder_tx_locktime as u64 & 0xffffff)) ^ commitment_transaction_number_obscure_factor),
-
- payment_preimages: HashMap::new(),
- pending_monitor_events: Vec::new(),
- pending_events: Vec::new(),
-
- onchain_events_waiting_threshold_conf: HashMap::new(),
- outputs_to_watch,
-
- onchain_tx_handler,
-
- lockdown_from_offchain: false,
- holder_tx_signed: false,
-
- last_block_hash: Default::default(),
- secp_ctx: Secp256k1::new(),
- }
- }
-
- /// 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
- /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
- pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
- if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
- return Err(MonitorUpdateError("Previous secret did not match new one"));
- }
-
- // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
- // events for now-revoked/fulfilled HTLCs.
- if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
- for &mut (_, ref mut source) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
- *source = None;
- }
- }
-
- if !self.payment_preimages.is_empty() {
- let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
- let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
- let min_idx = self.get_min_seen_secret();
- let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
-
- self.payment_preimages.retain(|&k, _| {
- for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
- if k == htlc.payment_hash {
- return true
- }
- }
- if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
- for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
- if k == htlc.payment_hash {
- return true
- }
- }
- }
- let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
- if *cn < min_idx {
- return true
- }
- true
- } else { false };
- if contains {
- counterparty_hash_commitment_number.remove(&k);
- }
- false
- });
- }
-
- Ok(())
- }
-
- /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
- /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
- /// possibly future revocation/preimage information) to claim outputs where possible.
- /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
- pub(crate) fn provide_latest_counterparty_commitment_tx_info<L: Deref>(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>, commitment_number: u64, their_revocation_point: PublicKey, logger: &L) where L::Target: Logger {
- // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
- // so that a remote monitor doesn't learn anything unless there is a malicious close.
- // (only maybe, sadly we cant do the same for local info, as we need to be aware of
- // timeouts)
- for &(ref htlc, _) in &htlc_outputs {
- self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
- }
-
- let new_txid = unsigned_commitment_tx.txid();
- log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
- log_trace!(logger, "New potential counterparty commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
- self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
- self.current_counterparty_commitment_txid = Some(new_txid);
- self.counterparty_claimable_outpoints.insert(new_txid, htlc_outputs.clone());
- self.current_counterparty_commitment_number = commitment_number;
- //TODO: Merge this into the other per-counterparty-transaction output storage stuff
- match self.their_cur_revocation_points {
- Some(old_points) => {
- if old_points.0 == commitment_number + 1 {
- self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
- } else if old_points.0 == commitment_number + 2 {
- if let Some(old_second_point) = old_points.2 {
- self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
- } else {
- self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
- }
- } else {
- self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
- }
- },
- None => {
- self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
- }
- }
- let mut htlcs = Vec::with_capacity(htlc_outputs.len());
- for htlc in htlc_outputs {
- if htlc.0.transaction_output_index.is_some() {
- htlcs.push(htlc.0);
- }
- }
- self.counterparty_tx_cache.per_htlc.insert(new_txid, htlcs);
- }
-
- /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
- /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
- /// is important that any clones of this channel monitor (including remote clones) by kept
- /// up-to-date as our holder commitment transaction is updated.
- /// Panics if set_on_holder_tx_csv has never been called.
- pub(super) fn provide_latest_holder_commitment_tx_info(&mut self, commitment_tx: HolderCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
- let txid = commitment_tx.txid();
- let sequence = commitment_tx.unsigned_tx.input[0].sequence as u64;
- let locktime = commitment_tx.unsigned_tx.lock_time as u64;
- let mut new_holder_commitment_tx = HolderSignedTx {
- txid,
- revocation_key: commitment_tx.keys.revocation_key,
- a_htlc_key: commitment_tx.keys.broadcaster_htlc_key,
- b_htlc_key: commitment_tx.keys.countersignatory_htlc_key,
- delayed_payment_key: commitment_tx.keys.broadcaster_delayed_payment_key,
- per_commitment_point: commitment_tx.keys.per_commitment_point,
- feerate_per_kw: commitment_tx.feerate_per_kw,
- htlc_outputs: htlc_outputs,
- };
- self.onchain_tx_handler.provide_latest_holder_tx(commitment_tx);
- self.current_holder_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
- mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
- self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
- if self.holder_tx_signed {
- return Err(MonitorUpdateError("Latest holder commitment signed has already been signed, update is rejected"));
- }
- Ok(())
- }
-
- /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
- /// commitment_tx_infos which contain the payment hash have been revoked.
- pub(crate) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
- self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
- }
-
- pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
- where B::Target: BroadcasterInterface,
- L::Target: Logger,
- {
- for tx in self.get_latest_holder_commitment_txn(logger).iter() {
- broadcaster.broadcast_transaction(tx);
- }
- self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
- }
-
- /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
- /// itself.
- ///
- /// panics if the given update is not the next update by update_id.
- pub fn update_monitor<B: Deref, L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B, logger: &L) -> Result<(), MonitorUpdateError>
- where B::Target: BroadcasterInterface,
- L::Target: Logger,
- {
- if self.latest_update_id + 1 != updates.update_id {
- panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
- }
- for update in updates.updates.drain(..) {
- match update {
- ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs } => {
- if self.lockdown_from_offchain { panic!(); }
- self.provide_latest_holder_commitment_tx_info(commitment_tx, htlc_outputs)?
- },
- ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
- self.provide_latest_counterparty_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
- ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
- self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
- ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
- self.provide_secret(idx, secret)?,
- ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
- self.lockdown_from_offchain = true;
- if should_broadcast {
- self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
- } else {
- log_error!(logger, "You have a toxic holder commitment transaction avaible in channel monitor, read comment in ChannelMonitor::get_latest_holder_commitment_txn to be informed of manual action to take");
- }
- }
- }
- }
- self.latest_update_id = updates.update_id;
- Ok(())
- }
-
- /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
- /// ChannelMonitor.
- pub fn get_latest_update_id(&self) -> u64 {
- self.latest_update_id
- }
-
- /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
- pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
- &self.funding_info
- }
-
- /// Gets a list of txids, with their output scripts (in the order they appear in the
- /// transaction), which we must learn about spends of via block_connected().
- ///
- /// (C-not exported) because we have no HashMap bindings
- pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<Script>> {
- &self.outputs_to_watch
- }
-
- /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
- /// Generally useful when deserializing as during normal operation the return values of
- /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
- /// that the get_funding_txo outpoint and transaction must also be monitored for!).
- ///
- /// (C-not exported) as there is no practical way to track lifetimes of returned values.
- pub fn get_monitored_outpoints(&self) -> Vec<(Txid, u32, &Script)> {
- let mut res = Vec::with_capacity(self.counterparty_commitment_txn_on_chain.len() * 2);
- for (ref txid, &(_, ref outputs)) in self.counterparty_commitment_txn_on_chain.iter() {
- for (idx, output) in outputs.iter().enumerate() {
- res.push(((*txid).clone(), idx as u32, output));
- }
- }
- res
- }
-
- /// Get the list of HTLCs who's status has been updated on chain. This should be called by
- /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
- ///
- /// [`chain::Watch::release_pending_monitor_events`]: ../../chain/trait.Watch.html#tymethod.release_pending_monitor_events
- pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
- let mut ret = Vec::new();
- mem::swap(&mut ret, &mut self.pending_monitor_events);
- ret
- }
-
- /// Gets the list of pending events which were generated by previous actions, clearing the list
- /// in the process.
- ///
- /// This is called by ChainMonitor::get_and_clear_pending_events() and is equivalent to
- /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
- /// no internal locking in ChannelMonitors.
- pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
- let mut ret = Vec::new();
- mem::swap(&mut ret, &mut self.pending_events);
- ret
- }
-
- /// Can only fail if idx is < get_min_seen_secret
- pub(crate) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
- self.commitment_secrets.get_secret(idx)
- }
-
- pub(crate) fn get_min_seen_secret(&self) -> u64 {
- self.commitment_secrets.get_min_seen_secret()
- }
-
- pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
- self.current_counterparty_commitment_number
- }
-
- pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
- self.current_holder_commitment_number
- }
-
- /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
- /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
- /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
- /// HTLC-Success/HTLC-Timeout transactions.
- /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
- /// revoked counterparty commitment tx
- fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
- // Most secp and related errors trying to create keys means we have no hope of constructing
- // a spend transaction...so we return no transactions to broadcast
- let mut claimable_outpoints = Vec::new();
- let mut watch_outputs = Vec::new();
-
- let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
- let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
-
- macro_rules! ignore_error {
- ( $thing : expr ) => {
- match $thing {
- Ok(a) => a,
- Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
- }
- };
- }
-
- let commitment_number = 0xffffffffffff - ((((tx.input[0].sequence as u64 & 0xffffff) << 3*8) | (tx.lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
- if commitment_number >= self.get_min_seen_secret() {
- let secret = self.get_secret(commitment_number).unwrap();
- let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
- let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
- let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
- let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.counterparty_tx_cache.counterparty_delayed_payment_base_key));
-
- let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_tx_cache.on_counterparty_tx_csv, &delayed_key);
- let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
-
- // First, process non-htlc outputs (to_holder & to_counterparty)
- for (idx, outp) in tx.output.iter().enumerate() {
- if outp.script_pubkey == revokeable_p2wsh {
- let witness_data = InputMaterial::Revoked { per_commitment_point, counterparty_delayed_payment_base_key: self.counterparty_tx_cache.counterparty_delayed_payment_base_key, counterparty_htlc_base_key: self.counterparty_tx_cache.counterparty_htlc_base_key, per_commitment_key, input_descriptor: InputDescriptors::RevokedOutput, amount: outp.value, htlc: None, on_counterparty_tx_csv: self.counterparty_tx_cache.on_counterparty_tx_csv};
- claimable_outpoints.push(ClaimRequest { absolute_timelock: height + self.counterparty_tx_cache.on_counterparty_tx_csv as u32, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 }, witness_data});
- }
- }
-
- // Then, try to find revoked htlc outputs
- if let Some(ref per_commitment_data) = per_commitment_option {
- for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
- if let Some(transaction_output_index) = htlc.transaction_output_index {
- if transaction_output_index as usize >= tx.output.len() ||
- tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
- return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
- }
- let witness_data = InputMaterial::Revoked { per_commitment_point, counterparty_delayed_payment_base_key: self.counterparty_tx_cache.counterparty_delayed_payment_base_key, counterparty_htlc_base_key: self.counterparty_tx_cache.counterparty_htlc_base_key, per_commitment_key, input_descriptor: if htlc.offered { InputDescriptors::RevokedOfferedHTLC } else { InputDescriptors::RevokedReceivedHTLC }, amount: tx.output[transaction_output_index as usize].value, htlc: Some(htlc.clone()), on_counterparty_tx_csv: self.counterparty_tx_cache.on_counterparty_tx_csv};
- claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
- }
- }
- }
-
- // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
- if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
- // We're definitely a counterparty commitment transaction!
- log_trace!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
- watch_outputs.append(&mut tx.output.clone());
- self.counterparty_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
-
- 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 {
- 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), $commitment_tx, height + ANTI_REORG_DELAY - 1);
- match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
- hash_map::Entry::Occupied(mut entry) => {
- let e = entry.get_mut();
- e.retain(|ref event| {
- match **event {
- OnchainEvent::HTLCUpdate { ref htlc_update } => {
- return htlc_update.0 != **source
- },
- _ => true
- }
- });
- e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
- }
- hash_map::Entry::Vacant(entry) => {
- entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
- }
- }
- }
- }
- }
- }
- }
- if let Some(ref txid) = self.current_counterparty_commitment_txid {
- check_htlc_fails!(txid, "current");
- }
- if let Some(ref txid) = self.prev_counterparty_commitment_txid {
- check_htlc_fails!(txid, "counterparty");
- }
- // No need to check holder commitment txn, symmetric HTLCSource must be present as per-htlc data on counterparty commitment tx
- }
- } else if let Some(per_commitment_data) = per_commitment_option {
- // While this isn't useful yet, there is a potential race where if a counterparty
- // revokes a state at the same time as the commitment transaction for that state is
- // confirmed, and the watchtower receives the block before the user, the user could
- // upload a new ChannelMonitor with the revocation secret but the watchtower has
- // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
- // not being generated by the above conditional. Thus, to be safe, we go ahead and
- // insert it here.
- watch_outputs.append(&mut tx.output.clone());
- self.counterparty_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
-
- log_trace!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
-
- macro_rules! check_htlc_fails {
- ($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);
- match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
- hash_map::Entry::Occupied(mut entry) => {
- let e = entry.get_mut();
- e.retain(|ref event| {
- match **event {
- OnchainEvent::HTLCUpdate { ref htlc_update } => {
- return htlc_update.0 != **source
- },
- _ => true
- }
- });
- e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
- }
- hash_map::Entry::Vacant(entry) => {
- entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
- }
- }
- }
- }
- }
- }
- }
- 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);
- }
-
- if let Some(revocation_points) = self.their_cur_revocation_points {
- let revocation_point_option =
- if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
- else if let Some(point) = revocation_points.2.as_ref() {
- if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
- } else { None };
- if let Some(revocation_point) = revocation_point_option {
- self.counterparty_payment_script = {
- // Note that the Network here is ignored as we immediately drop the address for the
- // script_pubkey version
- let payment_hash160 = WPubkeyHash::hash(&self.keys.pubkeys().payment_point.serialize());
- Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script()
- };
-
- // Then, try to find htlc outputs
- for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
- if let Some(transaction_output_index) = htlc.transaction_output_index {
- if transaction_output_index as usize >= tx.output.len() ||
- tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
- return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
- }
- let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
- let aggregable = if !htlc.offered { false } else { true };
- if preimage.is_some() || !htlc.offered {
- let witness_data = InputMaterial::CounterpartyHTLC { per_commitment_point: *revocation_point, counterparty_delayed_payment_base_key: self.counterparty_tx_cache.counterparty_delayed_payment_base_key, counterparty_htlc_base_key: self.counterparty_tx_cache.counterparty_htlc_base_key, preimage, htlc: htlc.clone() };
- claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
- }
- }
- }
- }
- }
- }
- (claimable_outpoints, (commitment_txid, watch_outputs))
- }
-
- /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
- fn check_spend_counterparty_htlc<L: Deref>(&mut self, tx: &Transaction, commitment_number: u64, height: u32, logger: &L) -> (Vec<ClaimRequest>, Option<(Txid, Vec<TxOut>)>) where L::Target: Logger {
- let htlc_txid = tx.txid();
- if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
- return (Vec::new(), None)
- }
-
- macro_rules! ignore_error {
- ( $thing : expr ) => {
- match $thing {
- Ok(a) => a,
- Err(_) => return (Vec::new(), None)
- }
- };
- }
-
- let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
- let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
- let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
-
- log_trace!(logger, "Counterparty HTLC broadcast {}:{}", htlc_txid, 0);
- let witness_data = InputMaterial::Revoked { per_commitment_point, counterparty_delayed_payment_base_key: self.counterparty_tx_cache.counterparty_delayed_payment_base_key, counterparty_htlc_base_key: self.counterparty_tx_cache.counterparty_htlc_base_key, per_commitment_key, input_descriptor: InputDescriptors::RevokedOutput, amount: tx.output[0].value, htlc: None, on_counterparty_tx_csv: self.counterparty_tx_cache.on_counterparty_tx_csv };
- let claimable_outpoints = vec!(ClaimRequest { absolute_timelock: height + self.counterparty_tx_cache.on_counterparty_tx_csv as u32, aggregable: true, outpoint: BitcoinOutPoint { txid: htlc_txid, vout: 0}, witness_data });
- (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
- }
-
- fn broadcast_by_holder_state(&self, commitment_tx: &Transaction, holder_tx: &HolderSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, PublicKey, PublicKey)>) {
- let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
- let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
-
- let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
- let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
-
- for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
- if let Some(transaction_output_index) = htlc.transaction_output_index {
- claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: holder_tx.txid, vout: transaction_output_index as u32 },
- witness_data: InputMaterial::HolderHTLC {
- preimage: if !htlc.offered {
- if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
- Some(preimage.clone())
- } else {
- // We can't build an HTLC-Success transaction without the preimage
- continue;
- }
- } else { None },
- amount: htlc.amount_msat,
- }});
- watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
- }
- }
-
- (claim_requests, watch_outputs, broadcasted_holder_revokable_script)
- }
-
- /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
- /// revoked using data in holder_claimable_outpoints.
- /// Should not be used if check_spend_revoked_transaction succeeds.
- fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
- let commitment_txid = tx.txid();
- let mut claim_requests = Vec::new();
- let mut watch_outputs = Vec::new();
-
- macro_rules! wait_threshold_conf {
- ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
- log_trace!(logger, "Failing HTLC with payment_hash {} from {} holder commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
- match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
- hash_map::Entry::Occupied(mut entry) => {
- let e = entry.get_mut();
- e.retain(|ref event| {
- match **event {
- OnchainEvent::HTLCUpdate { ref htlc_update } => {
- return htlc_update.0 != $source
- },
- _ => true
- }
- });
- e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
- }
- hash_map::Entry::Vacant(entry) => {
- entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
- }
- }
- }
- }
-
- macro_rules! append_onchain_update {
- ($updates: expr) => {
- claim_requests = $updates.0;
- watch_outputs.append(&mut $updates.1);
- self.broadcasted_holder_revokable_script = $updates.2;
- }
- }
-
- // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
- let mut is_holder_tx = false;
-
- if self.current_holder_commitment_tx.txid == commitment_txid {
- is_holder_tx = true;
- log_trace!(logger, "Got latest holder commitment tx broadcast, searching for available HTLCs to claim");
- let mut res = self.broadcast_by_holder_state(tx, &self.current_holder_commitment_tx);
- append_onchain_update!(res);
- } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
- if holder_tx.txid == commitment_txid {
- is_holder_tx = true;
- log_trace!(logger, "Got previous holder commitment tx broadcast, searching for available HTLCs to claim");
- let mut res = self.broadcast_by_holder_state(tx, holder_tx);
- append_onchain_update!(res);
- }
- }
-
- macro_rules! fail_dust_htlcs_after_threshold_conf {
- ($holder_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 {
- wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
- }
- }
- }
- }
- }
-
- if is_holder_tx {
- fail_dust_htlcs_after_threshold_conf!(self.current_holder_commitment_tx);
- if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
- fail_dust_htlcs_after_threshold_conf!(holder_tx);
- }
- }
-
- (claim_requests, (commitment_txid, watch_outputs))
- }
-
- /// 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
- /// a higher revocation secret than the holder commitment number we are aware of. Broadcasting these
- /// transactions are UNSAFE, as they allow counterparty side to punish you. Nevertheless you may want to
- /// broadcast them if counterparty don't close channel with his higher commitment transaction after a
- /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
- /// out-of-band the other node operator to coordinate with him if option is available to you.
- /// In any-case, choice is up to the user.
- pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
- log_trace!(logger, "Getting signed latest holder commitment transaction!");
- self.holder_tx_signed = true;
- if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript) {
- let txid = commitment_tx.txid();
- let mut res = vec![commitment_tx];
- for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
- if let Some(vout) = htlc.0.transaction_output_index {
- let preimage = if !htlc.0.offered {
- if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
- // We can't build an HTLC-Success transaction without the preimage
- continue;
- }
- } else { None };
- if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
- &::bitcoin::OutPoint { txid, vout }, &preimage) {
- res.push(htlc_tx);
- }
- }
- }
- // We throw away the generated waiting_first_conf data as we aren't (yet) confirmed and we don't actually know what the caller wants to do.
- // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
- return res
- }
- Vec::new()
- }
-
- /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
- /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
- /// revoked commitment transaction.
- #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
- pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
- log_trace!(logger, "Getting signed copy of latest holder commitment transaction!");
- if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript) {
- let txid = commitment_tx.txid();
- let mut res = vec![commitment_tx];
- for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
- if let Some(vout) = htlc.0.transaction_output_index {
- let preimage = if !htlc.0.offered {
- if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
- // We can't build an HTLC-Success transaction without the preimage
- continue;
- }
- } else { None };
- if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
- &::bitcoin::OutPoint { txid, vout }, &preimage) {
- res.push(htlc_tx);
- }
- }
- }
- return res
- }
- Vec::new()
- }
-
- /// Processes transactions in a newly connected block, which may result in any of the following:
- /// - update the monitor's state against resolved HTLCs
- /// - punish the counterparty in the case of seeing a revoked commitment transaction
- /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
- /// - detect settled outputs for later spending
- /// - schedule and bump any in-flight claims
- ///
- /// Returns any new outputs to watch from `txdata`; after called, these are also included in
- /// [`get_outputs_to_watch`].
- ///
- /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
- pub fn block_connected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, txdata: &TransactionData, height: u32, broadcaster: B, fee_estimator: F, logger: L)-> Vec<(Txid, Vec<TxOut>)>
- where B::Target: BroadcasterInterface,
- F::Target: FeeEstimator,
- L::Target: Logger,
- {
- let txn_matched = self.filter_block(txdata);
- for tx in &txn_matched {
- let mut output_val = 0;
- for out in tx.output.iter() {
- if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
- output_val += out.value;
- if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
- }
- }
-
- let block_hash = header.block_hash();
- log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
-
- let mut watch_outputs = Vec::new();
- let mut claimable_outpoints = Vec::new();
- for tx in &txn_matched {
- if tx.input.len() == 1 {
- // Assuming our keys were not leaked (in which case we're screwed no matter what),
- // commitment transactions and HTLC transactions will all only ever have one input,
- // which is an easy way to filter out any potential non-matching txn for lazy
- // filters.
- let prevout = &tx.input[0].previous_output;
- if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
- if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
- let (mut new_outpoints, new_outputs) = self.check_spend_counterparty_transaction(&tx, height, &logger);
- if !new_outputs.1.is_empty() {
- watch_outputs.push(new_outputs);
- }
- if new_outpoints.is_empty() {
- let (mut new_outpoints, new_outputs) = self.check_spend_holder_transaction(&tx, height, &logger);
- if !new_outputs.1.is_empty() {
- watch_outputs.push(new_outputs);
- }
- claimable_outpoints.append(&mut new_outpoints);
- }
- claimable_outpoints.append(&mut new_outpoints);
- }
- } else {
- if let Some(&(commitment_number, _)) = self.counterparty_commitment_txn_on_chain.get(&prevout.txid) {
- let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(&tx, commitment_number, height, &logger);
- claimable_outpoints.append(&mut new_outpoints);
- if let Some(new_outputs) = new_outputs_option {
- watch_outputs.push(new_outputs);
- }
- }
- }
- }
- // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
- // can also be resolved in a few other ways which can have more than one output. Thus,
- // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
- self.is_resolving_htlc_output(&tx, height, &logger);
-
- self.is_paying_spendable_output(&tx, height, &logger);
- }
- let should_broadcast = self.would_broadcast_at_height(height, &logger);
- if should_broadcast {
- claimable_outpoints.push(ClaimRequest { absolute_timelock: height, aggregable: false, outpoint: BitcoinOutPoint { txid: self.funding_info.0.txid.clone(), vout: self.funding_info.0.index as u32 }, witness_data: InputMaterial::Funding { funding_redeemscript: self.funding_redeemscript.clone() }});
- }
- if should_broadcast {
- self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
- if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript) {
- self.holder_tx_signed = true;
- let (mut new_outpoints, new_outputs, _) = self.broadcast_by_holder_state(&commitment_tx, &self.current_holder_commitment_tx);
- if !new_outputs.is_empty() {
- watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
- }
- claimable_outpoints.append(&mut new_outpoints);
- }
- }
- if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
- for ev in events {
- match ev {
- OnchainEvent::HTLCUpdate { htlc_update } => {
- log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
- self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
- payment_hash: htlc_update.1,
- payment_preimage: None,
- source: htlc_update.0,
- }));
- },
- OnchainEvent::MaturingOutput { descriptor } => {
- log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
- self.pending_events.push(Event::SpendableOutputs {
- outputs: vec![descriptor]
- });
- }
- }
- }
- }
-
- self.onchain_tx_handler.block_connected(&txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator, &*logger);
- self.last_block_hash = block_hash;
-
- // Determine new outputs to watch by comparing against previously known outputs to watch,
- // updating the latter in the process.
- watch_outputs.retain(|&(ref txid, ref txouts)| {
- let output_scripts = txouts.iter().map(|o| o.script_pubkey.clone()).collect();
- self.outputs_to_watch.insert(txid.clone(), output_scripts).is_none()
- });
- watch_outputs
- }
-
- /// Determines if the disconnected block contained any transactions of interest and updates
- /// appropriately.
- pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
- where B::Target: BroadcasterInterface,
- F::Target: FeeEstimator,
- L::Target: Logger,
- {
- let block_hash = header.block_hash();
- log_trace!(logger, "Block {} at height {} disconnected", block_hash, height);
-
- if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
- //We may discard:
- //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
- //- maturing spendable output has transaction paying us has been disconnected
- }
-
- self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
-
- self.last_block_hash = block_hash;
- }
-
- /// Filters a block's `txdata` for transactions spending watched outputs or for any child
- /// transactions thereof.
- fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
- let mut matched_txn = HashSet::new();
- txdata.iter().filter(|&&(_, tx)| {
- let mut matches = self.spends_watched_output(tx);
- for input in tx.input.iter() {
- if matches { break; }
- if matched_txn.contains(&input.previous_output.txid) {
- matches = true;
- }
- }
- if matches {
- matched_txn.insert(tx.txid());
- }
- matches
- }).map(|(_, tx)| *tx).collect()
- }
-
- /// Checks if a given transaction spends any watched outputs.
- fn spends_watched_output(&self, tx: &Transaction) -> bool {
- for input in tx.input.iter() {
- if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
- for (idx, _script_pubkey) in outputs.iter().enumerate() {
- if idx == input.previous_output.vout as usize {
- return true;
- }
- }
- }
- }
-
- false
- }
-
- fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
- // We need to consider all HTLCs which are:
- // * in any unrevoked counterparty commitment transaction, as they could broadcast said
- // transactions and we'd end up in a race, or
- // * are in our latest holder commitment transaction, as this is the thing we will
- // broadcast if we go on-chain.
- // Note that we consider HTLCs which were below dust threshold here - while they don't
- // strictly imply that we need to fail the channel, we need to go ahead and fail them back
- // to the source, and if we don't fail the channel we will have to ensure that the next
- // updates that peer sends us are update_fails, failing the channel if not. It's probably
- // easier to just fail the channel as this case should be rare enough anyway.
- macro_rules! scan_commitment {
- ($htlcs: expr, $holder_tx: expr) => {
- for ref htlc in $htlcs {
- // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
- // chain with enough room to claim the HTLC without our counterparty being able to
- // time out the HTLC first.
- // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
- // concern is being able to claim the corresponding inbound HTLC (on another
- // channel) before it expires. In fact, we don't even really care if our
- // counterparty here claims such an outbound HTLC after it expired as long as we
- // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
- // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
- // we give ourselves a few blocks of headroom after expiration before going
- // on-chain for an expired HTLC.
- // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
- // from us until we've reached the point where we go on-chain with the
- // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
- // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
- // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
- // inbound_cltv == height + CLTV_CLAIM_BUFFER
- // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
- // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
- // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
- // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
- // The final, above, condition is checked for statically in channelmanager
- // with CHECK_CLTV_EXPIRY_SANITY_2.
- let htlc_outbound = $holder_tx == htlc.offered;
- if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
- (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
- log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
- return true;
- }
- }
- }
- }
-
- scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
-
- if let Some(ref txid) = self.current_counterparty_commitment_txid {
- if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
- scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
- }
- }
- if let Some(ref txid) = self.prev_counterparty_commitment_txid {
- if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
- scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
- }
- }
-
- false
- }
-
- /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
- /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
- fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
- 'outer_loop: for input in &tx.input {
- let mut payment_data = None;
- let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
- || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
- let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
- let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
-
- macro_rules! log_claim {
- ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
- // We found the output in question, but aren't failing it backwards
- // as we have no corresponding source and no valid counterparty commitment txid
- // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
- // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
- let outbound_htlc = $holder_tx == $htlc.offered;
- if ($holder_tx && revocation_sig_claim) ||
- (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
- log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
- $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
- if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
- if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
- } else {
- log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
- $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
- if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
- if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
- }
- }
- }
-
- macro_rules! check_htlc_valid_counterparty {
- ($counterparty_txid: expr, $htlc_output: expr) => {
- if let Some(txid) = $counterparty_txid {
- for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
- if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
- if let &Some(ref source) = pending_source {
- log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
- payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
- break;
- }
- }
- }
- }
- }
- }
-
- macro_rules! scan_commitment {
- ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
- for (ref htlc_output, source_option) in $htlcs {
- if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
- if let Some(ref source) = source_option {
- log_claim!($tx_info, $holder_tx, htlc_output, true);
- // We have a resolution of an HTLC either from one of our latest
- // holder commitment transactions or an unrevoked counterparty commitment
- // transaction. This implies we either learned a preimage, the HTLC
- // has timed out, or we screwed up. In any case, we should now
- // resolve the source HTLC with the original sender.
- payment_data = Some(((*source).clone(), htlc_output.payment_hash));
- } else if !$holder_tx {
- check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
- if payment_data.is_none() {
- check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
- }
- }
- if payment_data.is_none() {
- log_claim!($tx_info, $holder_tx, htlc_output, false);
- continue 'outer_loop;
- }
- }
- }
- }
- }
-
- if input.previous_output.txid == self.current_holder_commitment_tx.txid {
- scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
- "our latest holder commitment tx", true);
- }
- if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
- if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
- scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
- "our previous holder commitment tx", true);
- }
- }
- if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
- scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
- "counterparty commitment tx", false);
- }
-
- // Check that scan_commitment, above, decided there is some source worth relaying an
- // HTLC resolution backwards to and figure out whether we learned a preimage from it.
- if let Some((source, payment_hash)) = payment_data {
- let mut payment_preimage = PaymentPreimage([0; 32]);
- if accepted_preimage_claim {
- if !self.pending_monitor_events.iter().any(
- |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
- payment_preimage.0.copy_from_slice(&input.witness[3]);
- self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
- source,
- payment_preimage: Some(payment_preimage),
- payment_hash
- }));
- }
- } else if offered_preimage_claim {
- if !self.pending_monitor_events.iter().any(
- |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
- upd.source == source
- } else { false }) {
- payment_preimage.0.copy_from_slice(&input.witness[1]);
- self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
- source,
- payment_preimage: Some(payment_preimage),
- payment_hash
- }));
- }
- } else {
- log_info!(logger, "Failing HTLC with payment_hash {} timeout by a spend tx, waiting for confirmation (at height{})", log_bytes!(payment_hash.0), height + ANTI_REORG_DELAY - 1);
- match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
- hash_map::Entry::Occupied(mut entry) => {
- let e = entry.get_mut();
- e.retain(|ref event| {
- match **event {
- OnchainEvent::HTLCUpdate { ref htlc_update } => {
- return htlc_update.0 != source
- },
- _ => true
- }
- });
- e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
- }
- hash_map::Entry::Vacant(entry) => {
- entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
- }
- }
- }
- }
- }
- }
-
- /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
- fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
- let mut spendable_output = None;
- for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
- if i > ::std::u16::MAX as usize {
- // While it is possible that an output exists on chain which is greater than the
- // 2^16th output in a given transaction, this is only possible if the output is not
- // in a lightning transaction and was instead placed there by some third party who
- // wishes to give us money for no reason.
- // Namely, any lightning transactions which we pre-sign will never have anywhere
- // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
- // scripts are not longer than one byte in length and because they are inherently
- // non-standard due to their size.
- // Thus, it is completely safe to ignore such outputs, and while it may result in
- // us ignoring non-lightning fund to us, that is only possible if someone fills
- // nearly a full block with garbage just to hit this case.
- continue;
- }
- if outp.script_pubkey == self.destination_script {
- spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
- outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
- output: outp.clone(),
- });
- break;
- } else if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
- if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
- spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
- outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
- per_commitment_point: broadcasted_holder_revokable_script.1,
- to_self_delay: self.on_holder_tx_csv,
- output: outp.clone(),
- key_derivation_params: self.keys.key_derivation_params(),
- revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
- });
- break;
- }
- } else if self.counterparty_payment_script == outp.script_pubkey {
- spendable_output = Some(SpendableOutputDescriptor::StaticOutputCounterpartyPayment {
- outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
- output: outp.clone(),
- key_derivation_params: self.keys.key_derivation_params(),
- });
- break;
- } else if outp.script_pubkey == self.shutdown_script {
- spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
- outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
- output: outp.clone(),
- });
- }
- }
- if let Some(spendable_output) = spendable_output {
- log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
- match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
- hash_map::Entry::Occupied(mut entry) => {
- let e = entry.get_mut();
- e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
- }
- hash_map::Entry::Vacant(entry) => {
- entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
- }
- }
- }
- }
-}
-
-const MAX_ALLOC_SIZE: usize = 64*1024;
-
-impl<ChanSigner: ChannelKeys + Readable> Readable for (BlockHash, ChannelMonitor<ChanSigner>) {
- fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
- macro_rules! unwrap_obj {
- ($key: expr) => {
- match $key {
- Ok(res) => res,
- Err(_) => return Err(DecodeError::InvalidValue),
- }
- }
- }
-
- let _ver: u8 = Readable::read(reader)?;
- let min_ver: u8 = Readable::read(reader)?;
- if min_ver > SERIALIZATION_VERSION {
- return Err(DecodeError::UnknownVersion);
- }
-
- let latest_update_id: u64 = Readable::read(reader)?;
- let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
-
- let destination_script = Readable::read(reader)?;
- let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
- 0 => {
- let revokable_address = Readable::read(reader)?;
- let per_commitment_point = Readable::read(reader)?;
- let revokable_script = Readable::read(reader)?;
- Some((revokable_address, per_commitment_point, revokable_script))
- },
- 1 => { None },
- _ => return Err(DecodeError::InvalidValue),
- };
- let counterparty_payment_script = Readable::read(reader)?;
- let shutdown_script = Readable::read(reader)?;
-
- let keys = Readable::read(reader)?;
- // Technically this can fail and serialize fail a round-trip, but only for serialization of
- // barely-init'd ChannelMonitors that we can't do anything with.
- let outpoint = OutPoint {
- txid: Readable::read(reader)?,
- index: Readable::read(reader)?,
- };
- let funding_info = (outpoint, Readable::read(reader)?);
- let current_counterparty_commitment_txid = Readable::read(reader)?;
- let prev_counterparty_commitment_txid = Readable::read(reader)?;
-
- let counterparty_tx_cache = Readable::read(reader)?;
- let funding_redeemscript = Readable::read(reader)?;
- let channel_value_satoshis = Readable::read(reader)?;
-
- let their_cur_revocation_points = {
- let first_idx = <U48 as Readable>::read(reader)?.0;
- if first_idx == 0 {
- None
- } else {
- let first_point = Readable::read(reader)?;
- let second_point_slice: [u8; 33] = Readable::read(reader)?;
- if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
- Some((first_idx, first_point, None))
- } else {
- Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
- }
- }
- };
-
- let on_holder_tx_csv: u16 = Readable::read(reader)?;
-
- let commitment_secrets = Readable::read(reader)?;
-
- macro_rules! read_htlc_in_commitment {
- () => {
- {
- let offered: bool = Readable::read(reader)?;
- let amount_msat: u64 = Readable::read(reader)?;
- let cltv_expiry: u32 = Readable::read(reader)?;
- let payment_hash: PaymentHash = Readable::read(reader)?;
- let transaction_output_index: Option<u32> = Readable::read(reader)?;
-
- HTLCOutputInCommitment {
- offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
- }
- }
- }
- }
-
- let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
- let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
- for _ in 0..counterparty_claimable_outpoints_len {
- let txid: Txid = Readable::read(reader)?;
- let htlcs_count: u64 = Readable::read(reader)?;
- let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
- for _ in 0..htlcs_count {
- htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
- }
- if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
- return Err(DecodeError::InvalidValue);
- }
- }
-
- let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
- let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
- for _ in 0..counterparty_commitment_txn_on_chain_len {
- let txid: Txid = Readable::read(reader)?;
- let commitment_number = <U48 as Readable>::read(reader)?.0;
- let outputs_count = <u64 as Readable>::read(reader)?;
- let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
- for _ in 0..outputs_count {
- outputs.push(Readable::read(reader)?);
- }
- if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
- return Err(DecodeError::InvalidValue);
- }
- }
-
- let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
- let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
- for _ in 0..counterparty_hash_commitment_number_len {
- let payment_hash: PaymentHash = Readable::read(reader)?;
- let commitment_number = <U48 as Readable>::read(reader)?.0;
- if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
- return Err(DecodeError::InvalidValue);
- }
- }
-
- macro_rules! read_holder_tx {
- () => {
- {
- let txid = Readable::read(reader)?;
- let revocation_key = Readable::read(reader)?;
- let a_htlc_key = Readable::read(reader)?;
- let b_htlc_key = Readable::read(reader)?;
- let delayed_payment_key = Readable::read(reader)?;
- let per_commitment_point = Readable::read(reader)?;
- let feerate_per_kw: u32 = Readable::read(reader)?;
-
- let htlcs_len: u64 = Readable::read(reader)?;
- let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
- for _ in 0..htlcs_len {
- let htlc = read_htlc_in_commitment!();
- let sigs = match <u8 as Readable>::read(reader)? {
- 0 => None,
- 1 => Some(Readable::read(reader)?),
- _ => return Err(DecodeError::InvalidValue),
- };
- htlcs.push((htlc, sigs, Readable::read(reader)?));
- }
-
- HolderSignedTx {
- txid,
- revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
- htlc_outputs: htlcs
- }
- }
- }
- }
-
- let prev_holder_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
- 0 => None,
- 1 => {
- Some(read_holder_tx!())
- },
- _ => return Err(DecodeError::InvalidValue),
- };
- let current_holder_commitment_tx = read_holder_tx!();
-
- let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
- let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
-
- let payment_preimages_len: u64 = Readable::read(reader)?;
- let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
- for _ in 0..payment_preimages_len {
- let preimage: PaymentPreimage = Readable::read(reader)?;
- let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
- if let Some(_) = payment_preimages.insert(hash, preimage) {
- return Err(DecodeError::InvalidValue);
- }
- }
-
- let pending_monitor_events_len: u64 = Readable::read(reader)?;
- let mut pending_monitor_events = Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
- for _ in 0..pending_monitor_events_len {
- let ev = match <u8 as Readable>::read(reader)? {
- 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
- 1 => MonitorEvent::CommitmentTxBroadcasted(funding_info.0),
- _ => return Err(DecodeError::InvalidValue)
- };
- pending_monitor_events.push(ev);
- }
-
- let pending_events_len: u64 = Readable::read(reader)?;
- let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
- for _ in 0..pending_events_len {
- if let Some(event) = MaybeReadable::read(reader)? {
- pending_events.push(event);
- }
- }
-
- let last_block_hash: BlockHash = Readable::read(reader)?;
-
- let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
- let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
- for _ in 0..waiting_threshold_conf_len {
- let height_target = Readable::read(reader)?;
- let events_len: u64 = Readable::read(reader)?;
- let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
- for _ in 0..events_len {
- let ev = match <u8 as Readable>::read(reader)? {
- 0 => {
- let htlc_source = Readable::read(reader)?;
- let hash = Readable::read(reader)?;
- OnchainEvent::HTLCUpdate {
- htlc_update: (htlc_source, hash)
- }
- },
- 1 => {
- let descriptor = Readable::read(reader)?;
- OnchainEvent::MaturingOutput {
- descriptor
- }
- },
- _ => return Err(DecodeError::InvalidValue),
- };
- events.push(ev);
- }
- onchain_events_waiting_threshold_conf.insert(height_target, events);
- }
-
- let outputs_to_watch_len: u64 = Readable::read(reader)?;
- let mut outputs_to_watch = HashMap::with_capacity(cmp::min(outputs_to_watch_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<Txid>() + mem::size_of::<Vec<Script>>())));
- for _ in 0..outputs_to_watch_len {
- let txid = Readable::read(reader)?;
- let outputs_len: u64 = Readable::read(reader)?;
- let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
- for _ in 0..outputs_len {
- outputs.push(Readable::read(reader)?);
- }
- if let Some(_) = outputs_to_watch.insert(txid, outputs) {
- return Err(DecodeError::InvalidValue);
- }
- }
- let onchain_tx_handler = Readable::read(reader)?;
-
- let lockdown_from_offchain = Readable::read(reader)?;
- let holder_tx_signed = Readable::read(reader)?;
-
- Ok((last_block_hash.clone(), ChannelMonitor {
- latest_update_id,
- commitment_transaction_number_obscure_factor,
-
- destination_script,
- broadcasted_holder_revokable_script,
- counterparty_payment_script,
- shutdown_script,
-
- keys,
- funding_info,
- current_counterparty_commitment_txid,
- prev_counterparty_commitment_txid,
-
- counterparty_tx_cache,
- funding_redeemscript,
- channel_value_satoshis,
- their_cur_revocation_points,
-
- on_holder_tx_csv,
-
- 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,
-
- payment_preimages,
- pending_monitor_events,
- pending_events,
-
- onchain_events_waiting_threshold_conf,
- outputs_to_watch,
-
- onchain_tx_handler,
-
- lockdown_from_offchain,
- holder_tx_signed,
-
- last_block_hash,
- secp_ctx: Secp256k1::new(),
- }))
- }
-}
-
-#[cfg(test)]
-mod tests {
- use bitcoin::blockdata::script::{Script, Builder};
- use bitcoin::blockdata::opcodes;
- use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
- use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
- use bitcoin::util::bip143;
- use bitcoin::hashes::Hash;
- use bitcoin::hashes::sha256::Hash as Sha256;
- use bitcoin::hashes::hex::FromHex;
- use bitcoin::hash_types::Txid;
- use hex;
- use chain::chainmonitor::ChannelMonitor;
- use chain::transaction::OutPoint;
- use ln::channelmanager::{PaymentPreimage, PaymentHash};
- use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
- use ln::chan_utils;
- use ln::chan_utils::{HTLCOutputInCommitment, HolderCommitmentTransaction};
- use util::test_utils::TestLogger;
- use bitcoin::secp256k1::key::{SecretKey,PublicKey};
- use bitcoin::secp256k1::Secp256k1;
- use std::sync::Arc;
- use chain::keysinterface::InMemoryChannelKeys;
-
- #[test]
- fn test_prune_preimages() {
- let secp_ctx = Secp256k1::new();
- let logger = Arc::new(TestLogger::new());
-
- let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
- let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
-
- let mut preimages = Vec::new();
- {
- for i in 0..20 {
- let preimage = PaymentPreimage([i; 32]);
- let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
- preimages.push((preimage, hash));
- }
- }
-
- macro_rules! preimages_slice_to_htlc_outputs {
- ($preimages_slice: expr) => {
- {
- let mut res = Vec::new();
- for (idx, preimage) in $preimages_slice.iter().enumerate() {
- res.push((HTLCOutputInCommitment {
- offered: true,
- amount_msat: 0,
- cltv_expiry: 0,
- payment_hash: preimage.1.clone(),
- transaction_output_index: Some(idx as u32),
- }, None));
- }
- res
- }
- }
- }
- macro_rules! preimages_to_holder_htlcs {
- ($preimages_slice: expr) => {
- {
- let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
- let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
- res
- }
- }
- }
-
- macro_rules! test_preimages_exist {
- ($preimages_slice: expr, $monitor: expr) => {
- for preimage in $preimages_slice {
- assert!($monitor.payment_preimages.contains_key(&preimage.1));
- }
- }
- }
-
- let keys = InMemoryChannelKeys::new(
- &secp_ctx,
- SecretKey::from_slice(&[41; 32]).unwrap(),
- SecretKey::from_slice(&[41; 32]).unwrap(),
- SecretKey::from_slice(&[41; 32]).unwrap(),
- SecretKey::from_slice(&[41; 32]).unwrap(),
- SecretKey::from_slice(&[41; 32]).unwrap(),
- [41; 32],
- 0,
- (0, 0)
- );
-
- // Prune with one old state and a holder commitment tx holding a few overlaps with the
- // old state.
- let mut monitor = ChannelMonitor::new(keys,
- &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
- (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
- &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
- &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
- 10, Script::new(), 46, 0, HolderCommitmentTransaction::dummy());
-
- monitor.provide_latest_holder_commitment_tx_info(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..10])).unwrap();
- monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
- monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
- monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
- monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
- for &(ref preimage, ref hash) in preimages.iter() {
- monitor.provide_payment_preimage(hash, preimage);
- }
-
- // Now provide a secret, pruning preimages 10-15
- let mut secret = [0; 32];
- secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
- monitor.provide_secret(281474976710655, secret.clone()).unwrap();
- assert_eq!(monitor.payment_preimages.len(), 15);
- test_preimages_exist!(&preimages[0..10], monitor);
- test_preimages_exist!(&preimages[15..20], monitor);
-
- // Now provide a further secret, pruning preimages 15-17
- secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
- monitor.provide_secret(281474976710654, secret.clone()).unwrap();
- assert_eq!(monitor.payment_preimages.len(), 13);
- test_preimages_exist!(&preimages[0..10], monitor);
- test_preimages_exist!(&preimages[17..20], monitor);
-
- // Now update holder commitment tx info, pruning only element 18 as we still care about the
- // previous commitment tx's preimages too
- monitor.provide_latest_holder_commitment_tx_info(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..5])).unwrap();
- secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
- monitor.provide_secret(281474976710653, secret.clone()).unwrap();
- assert_eq!(monitor.payment_preimages.len(), 12);
- test_preimages_exist!(&preimages[0..10], monitor);
- test_preimages_exist!(&preimages[18..20], monitor);
-
- // But if we do it again, we'll prune 5-10
- monitor.provide_latest_holder_commitment_tx_info(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..3])).unwrap();
- secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
- monitor.provide_secret(281474976710652, secret.clone()).unwrap();
- assert_eq!(monitor.payment_preimages.len(), 5);
- test_preimages_exist!(&preimages[0..5], monitor);
- }
-
- #[test]
- fn test_claim_txn_weight_computation() {
- // We test Claim txn weight, knowing that we want expected weigth and
- // not actual case to avoid sigs and time-lock delays hell variances.
-
- let secp_ctx = Secp256k1::new();
- let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
- let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
- let mut sum_actual_sigs = 0;
-
- macro_rules! sign_input {
- ($sighash_parts: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
- let htlc = HTLCOutputInCommitment {
- offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
- amount_msat: 0,
- cltv_expiry: 2 << 16,
- payment_hash: PaymentHash([1; 32]),
- transaction_output_index: Some($idx as u32),
- };
- let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
- let sighash = hash_to_message!(&$sighash_parts.signature_hash($idx, &redeem_script, $amount, SigHashType::All)[..]);
- let sig = secp_ctx.sign(&sighash, &privkey);
- $sighash_parts.access_witness($idx).push(sig.serialize_der().to_vec());
- $sighash_parts.access_witness($idx)[0].push(SigHashType::All as u8);
- sum_actual_sigs += $sighash_parts.access_witness($idx)[0].len();
- if *$input_type == InputDescriptors::RevokedOutput {
- $sighash_parts.access_witness($idx).push(vec!(1));
- } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
- $sighash_parts.access_witness($idx).push(pubkey.clone().serialize().to_vec());
- } else if *$input_type == InputDescriptors::ReceivedHTLC {
- $sighash_parts.access_witness($idx).push(vec![0]);
- } else {
- $sighash_parts.access_witness($idx).push(PaymentPreimage([1; 32]).0.to_vec());
- }
- $sighash_parts.access_witness($idx).push(redeem_script.into_bytes());
- println!("witness[0] {}", $sighash_parts.access_witness($idx)[0].len());
- println!("witness[1] {}", $sighash_parts.access_witness($idx)[1].len());
- println!("witness[2] {}", $sighash_parts.access_witness($idx)[2].len());
- }
- }
-
- let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
- let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
-
- // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
- let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
- for i in 0..4 {
- claim_tx.input.push(TxIn {
- previous_output: BitcoinOutPoint {
- txid,
- vout: i,
- },
- script_sig: Script::new(),
- sequence: 0xfffffffd,
- witness: Vec::new(),
- });
- }
- claim_tx.output.push(TxOut {
- script_pubkey: script_pubkey.clone(),
- value: 0,
- });
- let base_weight = claim_tx.get_weight();
- let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
- {
- let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
- for (idx, inp) in inputs_des.iter().enumerate() {
- sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
- }
- }
- assert_eq!(base_weight + OnchainTxHandler::<InMemoryChannelKeys>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
-
- // Claim tx with 1 offered HTLCs, 3 received HTLCs
- claim_tx.input.clear();
- sum_actual_sigs = 0;
- for i in 0..4 {
- claim_tx.input.push(TxIn {
- previous_output: BitcoinOutPoint {
- txid,
- vout: i,
- },
- script_sig: Script::new(),
- sequence: 0xfffffffd,
- witness: Vec::new(),
- });
- }
- let base_weight = claim_tx.get_weight();
- let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
- {
- let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
- for (idx, inp) in inputs_des.iter().enumerate() {
- sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
- }
- }
- assert_eq!(base_weight + OnchainTxHandler::<InMemoryChannelKeys>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
-
- // Justice tx with 1 revoked HTLC-Success tx output
- claim_tx.input.clear();
- sum_actual_sigs = 0;
- claim_tx.input.push(TxIn {
- previous_output: BitcoinOutPoint {
- txid,
- vout: 0,
- },
- script_sig: Script::new(),
- sequence: 0xfffffffd,
- witness: Vec::new(),
- });
- let base_weight = claim_tx.get_weight();
- let inputs_des = vec![InputDescriptors::RevokedOutput];
- {
- let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
- for (idx, inp) in inputs_des.iter().enumerate() {
- sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
- }
- }
- assert_eq!(base_weight + OnchainTxHandler::<InMemoryChannelKeys>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_des.len() - sum_actual_sigs));
- }
-
- // Further testing is done in the ChannelManager integration tests.
-}
++ /// [`chain::Filter`]: ../trait.Filter.html
+ fn add_monitor(&self, outpoint: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
+ let mut monitors = self.monitors.lock().unwrap();
+ let entry = match monitors.entry(outpoint) {
+ hash_map::Entry::Occupied(_) => return Err(MonitorUpdateError("Channel monitor for given outpoint is already present")),
+ hash_map::Entry::Vacant(e) => e,
+ };
+ {
+ let funding_txo = monitor.get_funding_txo();
+ log_trace!(self.logger, "Got new Channel Monitor for channel {}", log_bytes!(funding_txo.0.to_channel_id()[..]));
+
+ if let Some(ref chain_source) = self.chain_source {
+ chain_source.register_tx(&funding_txo.0.txid, &funding_txo.1);
+ for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
+ for (idx, script_pubkey) in outputs.iter().enumerate() {
+ chain_source.register_output(&OutPoint { txid: *txid, index: idx as u16 }, &script_pubkey);
+ }
+ }
+ }
+ }
+ entry.insert(monitor);
+ Ok(())
+ }
+
+ /// Updates the monitor that watches the channel referred to by the given outpoint.
+ fn update_monitor(&self, outpoint: OutPoint, update: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
+ let mut monitors = self.monitors.lock().unwrap();
+ match monitors.get_mut(&outpoint) {
+ Some(orig_monitor) => {
+ log_trace!(self.logger, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor));
+ orig_monitor.update_monitor(update, &self.broadcaster, &self.logger)
+ },
+ None => Err(MonitorUpdateError("No such monitor registered"))
+ }
+ }
+ }
+
+ impl<ChanSigner: ChannelKeys, C: Deref + Sync + Send, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send> chain::Watch for ChainMonitor<ChanSigner, C, T, F, L>
+ where C::Target: chain::Filter,
+ T::Target: BroadcasterInterface,
+ F::Target: FeeEstimator,
+ L::Target: Logger,
+ {
+ type Keys = ChanSigner;
+
+ fn watch_channel(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
+ match self.add_monitor(funding_txo, monitor) {
+ Ok(_) => Ok(()),
+ Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
+ }
+ }
+
+ fn update_channel(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
+ match self.update_monitor(funding_txo, update) {
+ Ok(_) => Ok(()),
+ Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
+ }
+ }
+
+ fn release_pending_monitor_events(&self) -> Vec<MonitorEvent> {
+ let mut pending_monitor_events = Vec::new();
+ for chan in self.monitors.lock().unwrap().values_mut() {
+ pending_monitor_events.append(&mut chan.get_and_clear_pending_monitor_events());
+ }
+ pending_monitor_events
+ }
+ }
+
+ impl<ChanSigner: ChannelKeys, C: Deref, T: Deref, F: Deref, L: Deref> events::EventsProvider for ChainMonitor<ChanSigner, C, T, F, L>
+ where C::Target: chain::Filter,
+ T::Target: BroadcasterInterface,
+ F::Target: FeeEstimator,
+ L::Target: Logger,
+ {
+ fn get_and_clear_pending_events(&self) -> Vec<Event> {
+ let mut pending_events = Vec::new();
+ for chan in self.monitors.lock().unwrap().values_mut() {
+ pending_events.append(&mut chan.get_and_clear_pending_events());
+ }
+ pending_events
+ }
+ }
--- /dev/null
- use chain;
- use chain::Filter;
+// 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.
+
+//! The logic to monitor for on-chain transactions and create the relevant claim responses lives
+//! here.
+//!
+//! ChannelMonitor objects are generated by ChannelManager in response to relevant
+//! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
+//! be made in responding to certain messages, see [`chain::Watch`] for more.
+//!
+//! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
+//! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
+//! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
+//! security-domain-separated system design, you should consider having multiple paths for
+//! ChannelMonitors to get out of the HSM and onto monitoring devices.
+//!
+//! [`chain::Watch`]: ../trait.Watch.html
+
+use bitcoin::blockdata::block::BlockHeader;
+use bitcoin::blockdata::transaction::{TxOut,Transaction};
+use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
+use bitcoin::blockdata::script::{Script, Builder};
+use bitcoin::blockdata::opcodes;
+use bitcoin::consensus::encode;
+
+use bitcoin::hashes::Hash;
+use bitcoin::hashes::sha256::Hash as Sha256;
+use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
+
+use bitcoin::secp256k1::{Secp256k1,Signature};
+use bitcoin::secp256k1::key::{SecretKey,PublicKey};
+use bitcoin::secp256k1;
+
+use ln::msgs::DecodeError;
+use ln::chan_utils;
+use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, HolderCommitmentTransaction, HTLCType};
+use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
+use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
- use util::{byte_utils, events};
+use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
+use chain::transaction::{OutPoint, TransactionData};
+use chain::keysinterface::{SpendableOutputDescriptor, ChannelKeys};
+use util::logger::Logger;
+use util::ser::{Readable, MaybeReadable, Writer, Writeable, U48};
- use std::sync::Mutex;
++use util::byte_utils;
+use util::events::Event;
+
+use std::collections::{HashMap, HashSet, hash_map};
- /// An implementation of [`chain::Watch`] for monitoring channels.
- ///
- /// Connected and disconnected blocks must be provided to `ChainMonitor` as documented by
- /// [`chain::Watch`]. May be used in conjunction with [`ChannelManager`] to monitor channels locally
- /// or used independently to monitor channels remotely.
- ///
- /// [`chain::Watch`]: ../trait.Watch.html
- /// [`ChannelManager`]: ../../ln/channelmanager/struct.ChannelManager.html
- pub struct ChainMonitor<ChanSigner: ChannelKeys, C: Deref, T: Deref, F: Deref, L: Deref>
- where C::Target: chain::Filter,
- T::Target: BroadcasterInterface,
- F::Target: FeeEstimator,
- L::Target: Logger,
- {
- /// The monitors
- pub monitors: Mutex<HashMap<OutPoint, ChannelMonitor<ChanSigner>>>,
- chain_source: Option<C>,
- broadcaster: T,
- logger: L,
- fee_estimator: F
- }
-
- impl<ChanSigner: ChannelKeys, C: Deref, T: Deref, F: Deref, L: Deref> ChainMonitor<ChanSigner, C, T, F, L>
- where C::Target: chain::Filter,
- T::Target: BroadcasterInterface,
- F::Target: FeeEstimator,
- L::Target: Logger,
- {
- /// Dispatches to per-channel monitors, which are responsible for updating their on-chain view
- /// of a channel and reacting accordingly based on transactions in the connected block. See
- /// [`ChannelMonitor::block_connected`] for details. Any HTLCs that were resolved on chain will
- /// be returned by [`chain::Watch::release_pending_monitor_events`].
- ///
- /// Calls back to [`chain::Filter`] if any monitor indicated new outputs to watch, returning
- /// `true` if so. Subsequent calls must not exclude any transactions matching the new outputs
- /// nor any in-block descendants of such transactions. It is not necessary to re-fetch the block
- /// to obtain updated `txdata`.
- ///
- /// [`ChannelMonitor::block_connected`]: struct.ChannelMonitor.html#method.block_connected
- /// [`chain::Watch::release_pending_monitor_events`]: ../trait.Watch.html#tymethod.release_pending_monitor_events
- /// [`chain::Filter`]: ../trait.Filter.html
- pub fn block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) -> bool {
- let mut has_new_outputs_to_watch = false;
- {
- let mut monitors = self.monitors.lock().unwrap();
- for monitor in monitors.values_mut() {
- let mut txn_outputs = monitor.block_connected(header, txdata, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
- has_new_outputs_to_watch |= !txn_outputs.is_empty();
-
- if let Some(ref chain_source) = self.chain_source {
- for (txid, outputs) in txn_outputs.drain(..) {
- for (idx, output) in outputs.iter().enumerate() {
- chain_source.register_output(&OutPoint { txid, index: idx as u16 }, &output.script_pubkey);
- }
- }
- }
- }
- }
- has_new_outputs_to_watch
- }
-
- /// Dispatches to per-channel monitors, which are responsible for updating their on-chain view
- /// of a channel based on the disconnected block. See [`ChannelMonitor::block_disconnected`] for
- /// details.
- ///
- /// [`ChannelMonitor::block_disconnected`]: struct.ChannelMonitor.html#method.block_disconnected
- pub fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
- let mut monitors = self.monitors.lock().unwrap();
- for monitor in monitors.values_mut() {
- monitor.block_disconnected(header, disconnected_height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
- }
- }
-
- /// Creates a new `ChainMonitor` used to watch on-chain activity pertaining to channels.
- ///
- /// When an optional chain source implementing [`chain::Filter`] is provided, the chain monitor
- /// will call back to it indicating transactions and outputs of interest. This allows clients to
- /// pre-filter blocks or only fetch blocks matching a compact filter. Otherwise, clients may
- /// always need to fetch full blocks absent another means for determining which blocks contain
- /// transactions relevant to the watched channels.
- ///
- /// [`chain::Filter`]: ../trait.Filter.html
- pub fn new(chain_source: Option<C>, broadcaster: T, logger: L, feeest: F) -> Self {
- Self {
- monitors: Mutex::new(HashMap::new()),
- chain_source,
- broadcaster,
- logger,
- fee_estimator: feeest,
- }
- }
-
- /// Adds the monitor that watches the channel referred to by the given outpoint.
- ///
- /// Calls back to [`chain::Filter`] with the funding transaction and outputs to watch.
- ///
- /// [`chain::Filter`]: ../trait.Filter.html
- fn add_monitor(&self, outpoint: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
- let mut monitors = self.monitors.lock().unwrap();
- let entry = match monitors.entry(outpoint) {
- hash_map::Entry::Occupied(_) => return Err(MonitorUpdateError("Channel monitor for given outpoint is already present")),
- hash_map::Entry::Vacant(e) => e,
- };
- {
- let funding_txo = monitor.get_funding_txo();
- log_trace!(self.logger, "Got new Channel Monitor for channel {}", log_bytes!(funding_txo.0.to_channel_id()[..]));
-
- if let Some(ref chain_source) = self.chain_source {
- chain_source.register_tx(&funding_txo.0.txid, &funding_txo.1);
- for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
- for (idx, script_pubkey) in outputs.iter().enumerate() {
- chain_source.register_output(&OutPoint { txid: *txid, index: idx as u16 }, &script_pubkey);
- }
- }
- }
- }
- entry.insert(monitor);
- Ok(())
- }
-
- /// Updates the monitor that watches the channel referred to by the given outpoint.
- fn update_monitor(&self, outpoint: OutPoint, update: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
- let mut monitors = self.monitors.lock().unwrap();
- match monitors.get_mut(&outpoint) {
- Some(orig_monitor) => {
- log_trace!(self.logger, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor));
- orig_monitor.update_monitor(update, &self.broadcaster, &self.logger)
- },
- None => Err(MonitorUpdateError("No such monitor registered"))
- }
- }
- }
-
- impl<ChanSigner: ChannelKeys, C: Deref + Sync + Send, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send> chain::Watch for ChainMonitor<ChanSigner, C, T, F, L>
- where C::Target: chain::Filter,
- T::Target: BroadcasterInterface,
- F::Target: FeeEstimator,
- L::Target: Logger,
- {
- type Keys = ChanSigner;
-
- fn watch_channel(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
- match self.add_monitor(funding_txo, monitor) {
- Ok(_) => Ok(()),
- Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
- }
- }
-
- fn update_channel(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
- match self.update_monitor(funding_txo, update) {
- Ok(_) => Ok(()),
- Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
- }
- }
-
- fn release_pending_monitor_events(&self) -> Vec<MonitorEvent> {
- let mut pending_monitor_events = Vec::new();
- for chan in self.monitors.lock().unwrap().values_mut() {
- pending_monitor_events.append(&mut chan.get_and_clear_pending_monitor_events());
- }
- pending_monitor_events
- }
- }
-
- impl<ChanSigner: ChannelKeys, C: Deref, T: Deref, F: Deref, L: Deref> events::EventsProvider for ChainMonitor<ChanSigner, C, T, F, L>
- where C::Target: chain::Filter,
- T::Target: BroadcasterInterface,
- F::Target: FeeEstimator,
- L::Target: Logger,
- {
- fn get_and_clear_pending_events(&self) -> Vec<Event> {
- let mut pending_events = Vec::new();
- for chan in self.monitors.lock().unwrap().values_mut() {
- pending_events.append(&mut chan.get_and_clear_pending_events());
- }
- pending_events
- }
- }
-
+use std::{cmp, mem};
+use std::ops::Deref;
+use std::io::Error;
+
+/// An update generated by the underlying Channel itself which contains some new information the
+/// ChannelMonitor should be made aware of.
+#[cfg_attr(test, derive(PartialEq))]
+#[derive(Clone)]
+#[must_use]
+pub struct ChannelMonitorUpdate {
+ pub(crate) updates: Vec<ChannelMonitorUpdateStep>,
+ /// The sequence number of this update. Updates *must* be replayed in-order according to this
+ /// sequence number (and updates may panic if they are not). The update_id values are strictly
+ /// increasing and increase by one for each new update.
+ ///
+ /// This sequence number is also used to track up to which points updates which returned
+ /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
+ /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
+ pub update_id: u64,
+}
+
+impl Writeable for ChannelMonitorUpdate {
+ fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+ self.update_id.write(w)?;
+ (self.updates.len() as u64).write(w)?;
+ for update_step in self.updates.iter() {
+ update_step.write(w)?;
+ }
+ Ok(())
+ }
+}
+impl Readable for ChannelMonitorUpdate {
+ fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
+ let update_id: u64 = Readable::read(r)?;
+ let len: u64 = Readable::read(r)?;
+ let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<ChannelMonitorUpdateStep>()));
+ for _ in 0..len {
+ updates.push(Readable::read(r)?);
+ }
+ Ok(Self { update_id, updates })
+ }
+}
+
+/// An error enum representing a failure to persist a channel monitor update.
+#[derive(Clone)]
+pub enum ChannelMonitorUpdateErr {
+ /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
+ /// our state failed, but is expected to succeed at some point in the future).
+ ///
+ /// Such a failure will "freeze" a channel, preventing us from revoking old states or
+ /// submitting new commitment transactions to the counterparty. Once the update(s) which failed
+ /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
+ /// restore the channel to an operational state.
+ ///
+ /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
+ /// you return a TemporaryFailure you must ensure that it is written to disk safely before
+ /// writing out the latest ChannelManager state.
+ ///
+ /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
+ /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
+ /// to claim it on this channel) and those updates must be applied wherever they can be. At
+ /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
+ /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
+ /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
+ /// been "frozen".
+ ///
+ /// Note that even if updates made after TemporaryFailure succeed you must still call
+ /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
+ /// operation.
+ ///
+ /// Note that the update being processed here will not be replayed for you when you call
+ /// ChannelManager::channel_monitor_updated, so you must store the update itself along
+ /// with the persisted ChannelMonitor on your own local disk prior to returning a
+ /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
+ /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
+ /// reload-time.
+ ///
+ /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
+ /// remote location (with local copies persisted immediately), it is anticipated that all
+ /// updates will return TemporaryFailure until the remote copies could be updated.
+ TemporaryFailure,
+ /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
+ /// different watchtower and cannot update with all watchtowers that were previously informed
+ /// of this channel).
+ ///
+ /// At reception of this error, ChannelManager will force-close the channel and return at
+ /// least a final ChannelMonitorUpdate::ChannelForceClosed which must be delivered to at
+ /// least one ChannelMonitor copy. Revocation secret MUST NOT be released and offchain channel
+ /// update must be rejected.
+ ///
+ /// This failure may also signal a failure to update the local persisted copy of one of
+ /// the channel monitor instance.
+ ///
+ /// Note that even when you fail a holder commitment transaction update, you must store the
+ /// update to ensure you can claim from it in case of a duplicate copy of this ChannelMonitor
+ /// broadcasts it (e.g distributed channel-monitor deployment)
+ ///
+ /// In case of distributed watchtowers deployment, the new version must be written to disk, as
+ /// state may have been stored but rejected due to a block forcing a commitment broadcast. This
+ /// storage is used to claim outputs of rejected state confirmed onchain by another watchtower,
+ /// lagging behind on block processing.
+ PermanentFailure,
+}
+
+/// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
+/// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
+/// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
+/// corrupted.
+/// Contains a human-readable error message.
+#[derive(Debug)]
+pub struct MonitorUpdateError(pub &'static str);
+
+/// An event to be processed by the ChannelManager.
+#[derive(PartialEq)]
+pub enum MonitorEvent {
+ /// A monitor event containing an HTLCUpdate.
+ HTLCEvent(HTLCUpdate),
+
+ /// A monitor event that the Channel's commitment transaction was broadcasted.
+ CommitmentTxBroadcasted(OutPoint),
+}
+
+/// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
+/// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
+/// preimage claim backward will lead to loss of funds.
+///
+/// [`chain::Watch`]: ../trait.Watch.html
+#[derive(Clone, PartialEq)]
+pub struct HTLCUpdate {
+ pub(crate) payment_hash: PaymentHash,
+ pub(crate) payment_preimage: Option<PaymentPreimage>,
+ pub(crate) source: HTLCSource
+}
+impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
+
+/// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
+/// instead claiming it in its own individual transaction.
+pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
+/// If an HTLC expires within this many blocks, force-close the channel to broadcast the
+/// HTLC-Success transaction.
+/// In other words, this is an upper bound on how many blocks we think it can take us to get a
+/// transaction confirmed (and we use it in a few more, equivalent, places).
+pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
+/// Number of blocks by which point we expect our counterparty to have seen new blocks on the
+/// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
+/// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
+/// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
+/// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
+/// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
+/// due to expiration but increase the cost of funds being locked longuer in case of failure.
+/// This delay also cover a low-power peer being slow to process blocks and so being behind us on
+/// accurate block height.
+/// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
+/// with at worst this delay, so we are not only using this value as a mercy for them but also
+/// us as a safeguard to delay with enough time.
+pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
+/// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
+/// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
+/// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
+/// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
+/// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
+/// keeping bumping another claim tx to solve the outpoint.
+pub(crate) const ANTI_REORG_DELAY: u32 = 6;
+/// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
+/// refuse to accept a new HTLC.
+///
+/// This is used for a few separate purposes:
+/// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
+/// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
+/// fail this HTLC,
+/// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
+/// condition with the above), we will fail this HTLC without telling the user we received it,
+/// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
+/// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
+///
+/// (1) is all about protecting us - we need enough time to update the channel state before we hit
+/// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
+///
+/// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
+/// in a race condition between the user connecting a block (which would fail it) and the user
+/// providing us the preimage (which would claim it).
+///
+/// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
+/// end up force-closing the channel on us to claim it.
+pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
+
+#[derive(Clone, PartialEq)]
+struct HolderSignedTx {
+ /// txid of the transaction in tx, just used to make comparison faster
+ txid: Txid,
+ revocation_key: PublicKey,
+ a_htlc_key: PublicKey,
+ b_htlc_key: PublicKey,
+ delayed_payment_key: PublicKey,
+ per_commitment_point: PublicKey,
+ feerate_per_kw: u32,
+ htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
+}
+
+/// We use this to track counterparty commitment transactions and htlcs outputs and
+/// use it to generate any justice or 2nd-stage preimage/timeout transactions.
+#[derive(PartialEq)]
+struct CounterpartyCommitmentTransaction {
+ counterparty_delayed_payment_base_key: PublicKey,
+ counterparty_htlc_base_key: PublicKey,
+ on_counterparty_tx_csv: u16,
+ per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
+}
+
+impl Writeable for CounterpartyCommitmentTransaction {
+ fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+ self.counterparty_delayed_payment_base_key.write(w)?;
+ self.counterparty_htlc_base_key.write(w)?;
+ w.write_all(&byte_utils::be16_to_array(self.on_counterparty_tx_csv))?;
+ w.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?;
+ for (ref txid, ref htlcs) in self.per_htlc.iter() {
+ w.write_all(&txid[..])?;
+ w.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
+ for &ref htlc in htlcs.iter() {
+ htlc.write(w)?;
+ }
+ }
+ Ok(())
+ }
+}
+impl Readable for CounterpartyCommitmentTransaction {
+ fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
+ let counterparty_commitment_transaction = {
+ let counterparty_delayed_payment_base_key = Readable::read(r)?;
+ let counterparty_htlc_base_key = Readable::read(r)?;
+ let on_counterparty_tx_csv: u16 = Readable::read(r)?;
+ let per_htlc_len: u64 = Readable::read(r)?;
+ let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
+ for _ in 0..per_htlc_len {
+ let txid: Txid = Readable::read(r)?;
+ let htlcs_count: u64 = Readable::read(r)?;
+ let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
+ for _ in 0..htlcs_count {
+ let htlc = Readable::read(r)?;
+ htlcs.push(htlc);
+ }
+ if let Some(_) = per_htlc.insert(txid, htlcs) {
+ return Err(DecodeError::InvalidValue);
+ }
+ }
+ CounterpartyCommitmentTransaction {
+ counterparty_delayed_payment_base_key,
+ counterparty_htlc_base_key,
+ on_counterparty_tx_csv,
+ per_htlc,
+ }
+ };
+ Ok(counterparty_commitment_transaction)
+ }
+}
+
+/// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
+/// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
+/// a new bumped one in case of lenghty confirmation delay
+#[derive(Clone, PartialEq)]
+pub(crate) enum InputMaterial {
+ Revoked {
+ per_commitment_point: PublicKey,
+ counterparty_delayed_payment_base_key: PublicKey,
+ counterparty_htlc_base_key: PublicKey,
+ per_commitment_key: SecretKey,
+ input_descriptor: InputDescriptors,
+ amount: u64,
+ htlc: Option<HTLCOutputInCommitment>,
+ on_counterparty_tx_csv: u16,
+ },
+ CounterpartyHTLC {
+ per_commitment_point: PublicKey,
+ counterparty_delayed_payment_base_key: PublicKey,
+ counterparty_htlc_base_key: PublicKey,
+ preimage: Option<PaymentPreimage>,
+ htlc: HTLCOutputInCommitment
+ },
+ HolderHTLC {
+ preimage: Option<PaymentPreimage>,
+ amount: u64,
+ },
+ Funding {
+ funding_redeemscript: Script,
+ }
+}
+
+impl Writeable for InputMaterial {
+ fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+ match self {
+ &InputMaterial::Revoked { ref per_commitment_point, ref counterparty_delayed_payment_base_key, ref counterparty_htlc_base_key, ref per_commitment_key, ref input_descriptor, ref amount, ref htlc, ref on_counterparty_tx_csv} => {
+ writer.write_all(&[0; 1])?;
+ per_commitment_point.write(writer)?;
+ counterparty_delayed_payment_base_key.write(writer)?;
+ counterparty_htlc_base_key.write(writer)?;
+ writer.write_all(&per_commitment_key[..])?;
+ input_descriptor.write(writer)?;
+ writer.write_all(&byte_utils::be64_to_array(*amount))?;
+ htlc.write(writer)?;
+ on_counterparty_tx_csv.write(writer)?;
+ },
+ &InputMaterial::CounterpartyHTLC { ref per_commitment_point, ref counterparty_delayed_payment_base_key, ref counterparty_htlc_base_key, ref preimage, ref htlc} => {
+ writer.write_all(&[1; 1])?;
+ per_commitment_point.write(writer)?;
+ counterparty_delayed_payment_base_key.write(writer)?;
+ counterparty_htlc_base_key.write(writer)?;
+ preimage.write(writer)?;
+ htlc.write(writer)?;
+ },
+ &InputMaterial::HolderHTLC { ref preimage, ref amount } => {
+ writer.write_all(&[2; 1])?;
+ preimage.write(writer)?;
+ writer.write_all(&byte_utils::be64_to_array(*amount))?;
+ },
+ &InputMaterial::Funding { ref funding_redeemscript } => {
+ writer.write_all(&[3; 1])?;
+ funding_redeemscript.write(writer)?;
+ }
+ }
+ Ok(())
+ }
+}
+
+impl Readable for InputMaterial {
+ fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
+ let input_material = match <u8 as Readable>::read(reader)? {
+ 0 => {
+ let per_commitment_point = Readable::read(reader)?;
+ let counterparty_delayed_payment_base_key = Readable::read(reader)?;
+ let counterparty_htlc_base_key = Readable::read(reader)?;
+ let per_commitment_key = Readable::read(reader)?;
+ let input_descriptor = Readable::read(reader)?;
+ let amount = Readable::read(reader)?;
+ let htlc = Readable::read(reader)?;
+ let on_counterparty_tx_csv = Readable::read(reader)?;
+ InputMaterial::Revoked {
+ per_commitment_point,
+ counterparty_delayed_payment_base_key,
+ counterparty_htlc_base_key,
+ per_commitment_key,
+ input_descriptor,
+ amount,
+ htlc,
+ on_counterparty_tx_csv
+ }
+ },
+ 1 => {
+ let per_commitment_point = Readable::read(reader)?;
+ let counterparty_delayed_payment_base_key = Readable::read(reader)?;
+ let counterparty_htlc_base_key = Readable::read(reader)?;
+ let preimage = Readable::read(reader)?;
+ let htlc = Readable::read(reader)?;
+ InputMaterial::CounterpartyHTLC {
+ per_commitment_point,
+ counterparty_delayed_payment_base_key,
+ counterparty_htlc_base_key,
+ preimage,
+ htlc
+ }
+ },
+ 2 => {
+ let preimage = Readable::read(reader)?;
+ let amount = Readable::read(reader)?;
+ InputMaterial::HolderHTLC {
+ preimage,
+ amount,
+ }
+ },
+ 3 => {
+ InputMaterial::Funding {
+ funding_redeemscript: Readable::read(reader)?,
+ }
+ }
+ _ => return Err(DecodeError::InvalidValue),
+ };
+ Ok(input_material)
+ }
+}
+
+/// ClaimRequest is a descriptor structure to communicate between detection
+/// and reaction module. They are generated by ChannelMonitor while parsing
+/// onchain txn leaked from a channel and handed over to OnchainTxHandler which
+/// is responsible for opportunistic aggregation, selecting and enforcing
+/// bumping logic, building and signing transactions.
+pub(crate) struct ClaimRequest {
+ // Block height before which claiming is exclusive to one party,
+ // after reaching it, claiming may be contentious.
+ pub(crate) absolute_timelock: u32,
+ // Timeout tx must have nLocktime set which means aggregating multiple
+ // ones must take the higher nLocktime among them to satisfy all of them.
+ // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
+ // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
+ // Do simplify we mark them as non-aggregable.
+ pub(crate) aggregable: bool,
+ // Basic bitcoin outpoint (txid, vout)
+ pub(crate) outpoint: BitcoinOutPoint,
+ // Following outpoint type, set of data needed to generate transaction digest
+ // and satisfy witness program.
+ pub(crate) witness_data: InputMaterial
+}
+
+/// 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(Clone, PartialEq)]
+enum OnchainEvent {
+ /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
+ /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
+ /// only win from it, so it's never an OnchainEvent
+ HTLCUpdate {
+ htlc_update: (HTLCSource, PaymentHash),
+ },
+ MaturingOutput {
+ descriptor: SpendableOutputDescriptor,
+ },
+}
+
+const SERIALIZATION_VERSION: u8 = 1;
+const MIN_SERIALIZATION_VERSION: u8 = 1;
+
+#[cfg_attr(test, derive(PartialEq))]
+#[derive(Clone)]
+pub(crate) enum ChannelMonitorUpdateStep {
+ LatestHolderCommitmentTXInfo {
+ commitment_tx: HolderCommitmentTransaction,
+ htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
+ },
+ LatestCounterpartyCommitmentTXInfo {
+ unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
+ htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
+ commitment_number: u64,
+ their_revocation_point: PublicKey,
+ },
+ PaymentPreimage {
+ payment_preimage: PaymentPreimage,
+ },
+ CommitmentSecret {
+ idx: u64,
+ secret: [u8; 32],
+ },
+ /// Used to indicate that the no future updates will occur, and likely that the latest holder
+ /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
+ ChannelForceClosed {
+ /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
+ /// think we've fallen behind!
+ should_broadcast: bool,
+ },
+}
+
+impl Writeable for ChannelMonitorUpdateStep {
+ fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+ match self {
+ &ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
+ 0u8.write(w)?;
+ commitment_tx.write(w)?;
+ (htlc_outputs.len() as u64).write(w)?;
+ for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
+ output.write(w)?;
+ signature.write(w)?;
+ source.write(w)?;
+ }
+ }
+ &ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
+ 1u8.write(w)?;
+ unsigned_commitment_tx.write(w)?;
+ commitment_number.write(w)?;
+ their_revocation_point.write(w)?;
+ (htlc_outputs.len() as u64).write(w)?;
+ for &(ref output, ref source) in htlc_outputs.iter() {
+ output.write(w)?;
+ source.as_ref().map(|b| b.as_ref()).write(w)?;
+ }
+ },
+ &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
+ 2u8.write(w)?;
+ payment_preimage.write(w)?;
+ },
+ &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
+ 3u8.write(w)?;
+ idx.write(w)?;
+ secret.write(w)?;
+ },
+ &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
+ 4u8.write(w)?;
+ should_broadcast.write(w)?;
+ },
+ }
+ Ok(())
+ }
+}
+impl Readable for ChannelMonitorUpdateStep {
+ fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
+ match Readable::read(r)? {
+ 0u8 => {
+ Ok(ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
+ commitment_tx: Readable::read(r)?,
+ htlc_outputs: {
+ let len: u64 = Readable::read(r)?;
+ let mut res = Vec::new();
+ for _ in 0..len {
+ res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
+ }
+ res
+ },
+ })
+ },
+ 1u8 => {
+ Ok(ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
+ unsigned_commitment_tx: Readable::read(r)?,
+ commitment_number: Readable::read(r)?,
+ their_revocation_point: Readable::read(r)?,
+ htlc_outputs: {
+ let len: u64 = Readable::read(r)?;
+ let mut res = Vec::new();
+ for _ in 0..len {
+ res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
+ }
+ res
+ },
+ })
+ },
+ 2u8 => {
+ Ok(ChannelMonitorUpdateStep::PaymentPreimage {
+ payment_preimage: Readable::read(r)?,
+ })
+ },
+ 3u8 => {
+ Ok(ChannelMonitorUpdateStep::CommitmentSecret {
+ idx: Readable::read(r)?,
+ secret: Readable::read(r)?,
+ })
+ },
+ 4u8 => {
+ Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
+ should_broadcast: Readable::read(r)?
+ })
+ },
+ _ => Err(DecodeError::InvalidValue),
+ }
+ }
+}
+
+/// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
+/// on-chain transactions to ensure no loss of funds occurs.
+///
+/// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
+/// information and are actively monitoring the chain.
+///
+/// Pending Events or updated HTLCs which have not yet been read out by
+/// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
+/// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
+/// gotten are fully handled before re-serializing the new state.
+pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
+ latest_update_id: u64,
+ commitment_transaction_number_obscure_factor: u64,
+
+ destination_script: Script,
+ broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
+ counterparty_payment_script: Script,
+ shutdown_script: Script,
+
+ keys: ChanSigner,
+ funding_info: (OutPoint, Script),
+ current_counterparty_commitment_txid: Option<Txid>,
+ prev_counterparty_commitment_txid: Option<Txid>,
+
+ counterparty_tx_cache: CounterpartyCommitmentTransaction,
+ funding_redeemscript: Script,
+ channel_value_satoshis: u64,
+ // first is the idx of the first of the two revocation points
+ their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
+
+ on_holder_tx_csv: u16,
+
+ commitment_secrets: CounterpartyCommitmentSecrets,
+ 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
+ /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
+ /// commitment transactions which we find on-chain, mapping them to the commitment number which
+ /// can be used to derive the revocation key and claim the transactions.
+ counterparty_commitment_txn_on_chain: HashMap<Txid, (u64, Vec<Script>)>,
+ /// Cache used to make pruning of payment_preimages faster.
+ /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
+ /// counterparty transactions (ie should remain pretty small).
+ /// Serialized to disk but should generally not be sent to Watchtowers.
+ counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
+
+ // We store two holder commitment transactions to avoid any race conditions where we may update
+ // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
+ // various monitors for one channel being out of sync, and us broadcasting a holder
+ // transaction for which we have deleted claim information on some watchtowers.
+ prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
+ current_holder_commitment_tx: HolderSignedTx,
+
+ // Used just for ChannelManager to make sure it has the latest channel data during
+ // deserialization
+ current_counterparty_commitment_number: u64,
+ // Used just for ChannelManager to make sure it has the latest channel data during
+ // deserialization
+ current_holder_commitment_number: u64,
+
+ payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
+
+ pending_monitor_events: Vec<MonitorEvent>,
+ pending_events: Vec<Event>,
+
+ // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
+ // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
+ // actions when we receive a block with given height. Actions depend on OnchainEvent type.
+ onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
+
+ // If we get serialized out and re-read, we need to make sure that the chain monitoring
+ // interface knows about the TXOs that we want to be notified of spends of. We could probably
+ // be smart and derive them from the above storage fields, but its much simpler and more
+ // Obviously Correct (tm) if we just keep track of them explicitly.
+ outputs_to_watch: HashMap<Txid, Vec<Script>>,
+
+ #[cfg(test)]
+ pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
+ #[cfg(not(test))]
+ onchain_tx_handler: OnchainTxHandler<ChanSigner>,
+
+ // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
+ // channel has been force-closed. After this is set, no further holder commitment transaction
+ // updates may occur, and we panic!() if one is provided.
+ lockdown_from_offchain: bool,
+
+ // Set once we've signed a holder commitment transaction and handed it over to our
+ // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
+ // may occur, and we fail any such monitor updates.
+ //
+ // In case of update rejection due to a locally already signed commitment transaction, we
+ // nevertheless store update content to track in case of concurrent broadcast by another
+ // remote monitor out-of-order with regards to the block view.
+ holder_tx_signed: bool,
+
+ // We simply modify last_block_hash in Channel's block_connected so that serialization is
+ // consistent but hopefully the users' copy handles block_connected in a consistent way.
+ // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
+ // their last_block_hash from its state and not based on updated copies that didn't run through
+ // the full block_connected).
+ last_block_hash: BlockHash,
+ secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
+}
+
+#[cfg(any(test, feature = "fuzztarget"))]
+/// Used only in testing and fuzztarget to check serialization roundtrips don't change the
+/// underlying object
+impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
+ fn eq(&self, other: &Self) -> bool {
+ if self.latest_update_id != other.latest_update_id ||
+ self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
+ self.destination_script != other.destination_script ||
+ self.broadcasted_holder_revokable_script != other.broadcasted_holder_revokable_script ||
+ self.counterparty_payment_script != other.counterparty_payment_script ||
+ self.keys.pubkeys() != other.keys.pubkeys() ||
+ self.funding_info != other.funding_info ||
+ self.current_counterparty_commitment_txid != other.current_counterparty_commitment_txid ||
+ self.prev_counterparty_commitment_txid != other.prev_counterparty_commitment_txid ||
+ self.counterparty_tx_cache != other.counterparty_tx_cache ||
+ self.funding_redeemscript != other.funding_redeemscript ||
+ self.channel_value_satoshis != other.channel_value_satoshis ||
+ self.their_cur_revocation_points != other.their_cur_revocation_points ||
+ self.on_holder_tx_csv != other.on_holder_tx_csv ||
+ self.commitment_secrets != other.commitment_secrets ||
+ self.counterparty_claimable_outpoints != other.counterparty_claimable_outpoints ||
+ self.counterparty_commitment_txn_on_chain != other.counterparty_commitment_txn_on_chain ||
+ self.counterparty_hash_commitment_number != other.counterparty_hash_commitment_number ||
+ self.prev_holder_signed_commitment_tx != other.prev_holder_signed_commitment_tx ||
+ self.current_counterparty_commitment_number != other.current_counterparty_commitment_number ||
+ self.current_holder_commitment_number != other.current_holder_commitment_number ||
+ self.current_holder_commitment_tx != other.current_holder_commitment_tx ||
+ self.payment_preimages != other.payment_preimages ||
+ self.pending_monitor_events != other.pending_monitor_events ||
+ self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
+ self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
+ self.outputs_to_watch != other.outputs_to_watch ||
+ self.lockdown_from_offchain != other.lockdown_from_offchain ||
+ self.holder_tx_signed != other.holder_tx_signed
+ {
+ false
+ } else {
+ true
+ }
+ }
+}
+
+impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
+ /// Writes this monitor into the given writer, suitable for writing to disk.
+ ///
+ /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
+ /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
+ /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
+ /// returned block hash and the the current chain and then reconnecting blocks to get to the
+ /// best chain) upon deserializing the object!
+ pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
+ //TODO: We still write out all the serialization here manually instead of using the fancy
+ //serialization framework we have, we should migrate things over to it.
+ writer.write_all(&[SERIALIZATION_VERSION; 1])?;
+ writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
+
+ self.latest_update_id.write(writer)?;
+
+ // Set in initial Channel-object creation, so should always be set by now:
+ U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
+
+ self.destination_script.write(writer)?;
+ if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
+ writer.write_all(&[0; 1])?;
+ broadcasted_holder_revokable_script.0.write(writer)?;
+ broadcasted_holder_revokable_script.1.write(writer)?;
+ broadcasted_holder_revokable_script.2.write(writer)?;
+ } else {
+ writer.write_all(&[1; 1])?;
+ }
+
+ self.counterparty_payment_script.write(writer)?;
+ self.shutdown_script.write(writer)?;
+
+ self.keys.write(writer)?;
+ writer.write_all(&self.funding_info.0.txid[..])?;
+ writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
+ self.funding_info.1.write(writer)?;
+ self.current_counterparty_commitment_txid.write(writer)?;
+ self.prev_counterparty_commitment_txid.write(writer)?;
+
+ self.counterparty_tx_cache.write(writer)?;
+ self.funding_redeemscript.write(writer)?;
+ self.channel_value_satoshis.write(writer)?;
+
+ match self.their_cur_revocation_points {
+ Some((idx, pubkey, second_option)) => {
+ writer.write_all(&byte_utils::be48_to_array(idx))?;
+ writer.write_all(&pubkey.serialize())?;
+ match second_option {
+ Some(second_pubkey) => {
+ writer.write_all(&second_pubkey.serialize())?;
+ },
+ None => {
+ writer.write_all(&[0; 33])?;
+ },
+ }
+ },
+ None => {
+ writer.write_all(&byte_utils::be48_to_array(0))?;
+ },
+ }
+
+ writer.write_all(&byte_utils::be16_to_array(self.on_holder_tx_csv))?;
+
+ self.commitment_secrets.write(writer)?;
+
+ macro_rules! serialize_htlc_in_commitment {
+ ($htlc_output: expr) => {
+ writer.write_all(&[$htlc_output.offered as u8; 1])?;
+ writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
+ writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
+ writer.write_all(&$htlc_output.payment_hash.0[..])?;
+ $htlc_output.transaction_output_index.write(writer)?;
+ }
+ }
+
+ writer.write_all(&byte_utils::be64_to_array(self.counterparty_claimable_outpoints.len() as u64))?;
+ for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
+ writer.write_all(&txid[..])?;
+ writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
+ for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
+ serialize_htlc_in_commitment!(htlc_output);
+ htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
+ }
+ }
+
+ writer.write_all(&byte_utils::be64_to_array(self.counterparty_commitment_txn_on_chain.len() as u64))?;
+ for (ref txid, &(commitment_number, ref txouts)) in self.counterparty_commitment_txn_on_chain.iter() {
+ writer.write_all(&txid[..])?;
+ writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
+ (txouts.len() as u64).write(writer)?;
+ for script in txouts.iter() {
+ script.write(writer)?;
+ }
+ }
+
+ writer.write_all(&byte_utils::be64_to_array(self.counterparty_hash_commitment_number.len() as u64))?;
+ for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
+ writer.write_all(&payment_hash.0[..])?;
+ writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
+ }
+
+ macro_rules! serialize_holder_tx {
+ ($holder_tx: expr) => {
+ $holder_tx.txid.write(writer)?;
+ writer.write_all(&$holder_tx.revocation_key.serialize())?;
+ writer.write_all(&$holder_tx.a_htlc_key.serialize())?;
+ writer.write_all(&$holder_tx.b_htlc_key.serialize())?;
+ writer.write_all(&$holder_tx.delayed_payment_key.serialize())?;
+ writer.write_all(&$holder_tx.per_commitment_point.serialize())?;
+
+ writer.write_all(&byte_utils::be32_to_array($holder_tx.feerate_per_kw))?;
+ writer.write_all(&byte_utils::be64_to_array($holder_tx.htlc_outputs.len() as u64))?;
+ for &(ref htlc_output, ref sig, ref htlc_source) in $holder_tx.htlc_outputs.iter() {
+ serialize_htlc_in_commitment!(htlc_output);
+ if let &Some(ref their_sig) = sig {
+ 1u8.write(writer)?;
+ writer.write_all(&their_sig.serialize_compact())?;
+ } else {
+ 0u8.write(writer)?;
+ }
+ htlc_source.write(writer)?;
+ }
+ }
+ }
+
+ if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
+ writer.write_all(&[1; 1])?;
+ serialize_holder_tx!(prev_holder_tx);
+ } else {
+ writer.write_all(&[0; 1])?;
+ }
+
+ serialize_holder_tx!(self.current_holder_commitment_tx);
+
+ writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
+ writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
+
+ writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
+ for payment_preimage in self.payment_preimages.values() {
+ writer.write_all(&payment_preimage.0[..])?;
+ }
+
+ writer.write_all(&byte_utils::be64_to_array(self.pending_monitor_events.len() as u64))?;
+ for event in self.pending_monitor_events.iter() {
+ match event {
+ MonitorEvent::HTLCEvent(upd) => {
+ 0u8.write(writer)?;
+ upd.write(writer)?;
+ },
+ MonitorEvent::CommitmentTxBroadcasted(_) => 1u8.write(writer)?
+ }
+ }
+
+ writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
+ for event in self.pending_events.iter() {
+ event.write(writer)?;
+ }
+
+ self.last_block_hash.write(writer)?;
+
+ writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
+ for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
+ writer.write_all(&byte_utils::be32_to_array(**target))?;
+ writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
+ for ev in events.iter() {
+ match *ev {
+ OnchainEvent::HTLCUpdate { ref htlc_update } => {
+ 0u8.write(writer)?;
+ htlc_update.0.write(writer)?;
+ htlc_update.1.write(writer)?;
+ },
+ OnchainEvent::MaturingOutput { ref descriptor } => {
+ 1u8.write(writer)?;
+ descriptor.write(writer)?;
+ },
+ }
+ }
+ }
+
+ (self.outputs_to_watch.len() as u64).write(writer)?;
+ for (txid, output_scripts) in self.outputs_to_watch.iter() {
+ txid.write(writer)?;
+ (output_scripts.len() as u64).write(writer)?;
+ for script in output_scripts.iter() {
+ script.write(writer)?;
+ }
+ }
+ self.onchain_tx_handler.write(writer)?;
+
+ self.lockdown_from_offchain.write(writer)?;
+ self.holder_tx_signed.write(writer)?;
+
+ Ok(())
+ }
+}
+
+impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
+ pub(crate) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
+ on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
+ counterparty_htlc_base_key: &PublicKey, counterparty_delayed_payment_base_key: &PublicKey,
+ on_holder_tx_csv: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
+ commitment_transaction_number_obscure_factor: u64,
+ initial_holder_commitment_tx: HolderCommitmentTransaction) -> ChannelMonitor<ChanSigner> {
+
+ assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
+ let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
+ let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
+ let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
+ let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
+
+ let counterparty_tx_cache = CounterpartyCommitmentTransaction { counterparty_delayed_payment_base_key: *counterparty_delayed_payment_base_key, counterparty_htlc_base_key: *counterparty_htlc_base_key, on_counterparty_tx_csv, per_htlc: HashMap::new() };
+
+ let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys.clone(), on_holder_tx_csv);
+
+ let holder_tx_sequence = initial_holder_commitment_tx.unsigned_tx.input[0].sequence as u64;
+ let holder_tx_locktime = initial_holder_commitment_tx.unsigned_tx.lock_time as u64;
+ let holder_commitment_tx = HolderSignedTx {
+ txid: initial_holder_commitment_tx.txid(),
+ revocation_key: initial_holder_commitment_tx.keys.revocation_key,
+ a_htlc_key: initial_holder_commitment_tx.keys.broadcaster_htlc_key,
+ b_htlc_key: initial_holder_commitment_tx.keys.countersignatory_htlc_key,
+ delayed_payment_key: initial_holder_commitment_tx.keys.broadcaster_delayed_payment_key,
+ per_commitment_point: initial_holder_commitment_tx.keys.per_commitment_point,
+ feerate_per_kw: initial_holder_commitment_tx.feerate_per_kw,
+ htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
+ };
+ onchain_tx_handler.provide_latest_holder_tx(initial_holder_commitment_tx);
+
+ let mut outputs_to_watch = HashMap::new();
+ outputs_to_watch.insert(funding_info.0.txid, vec![funding_info.1.clone()]);
+
+ ChannelMonitor {
+ latest_update_id: 0,
+ commitment_transaction_number_obscure_factor,
+
+ destination_script: destination_script.clone(),
+ broadcasted_holder_revokable_script: None,
+ counterparty_payment_script,
+ shutdown_script,
+
+ keys,
+ funding_info,
+ current_counterparty_commitment_txid: None,
+ prev_counterparty_commitment_txid: None,
+
+ counterparty_tx_cache,
+ funding_redeemscript,
+ channel_value_satoshis: channel_value_satoshis,
+ their_cur_revocation_points: None,
+
+ on_holder_tx_csv,
+
+ 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: 0xffff_ffff_ffff - ((((holder_tx_sequence & 0xffffff) << 3*8) | (holder_tx_locktime as u64 & 0xffffff)) ^ commitment_transaction_number_obscure_factor),
+
+ payment_preimages: HashMap::new(),
+ pending_monitor_events: Vec::new(),
+ pending_events: Vec::new(),
+
+ onchain_events_waiting_threshold_conf: HashMap::new(),
+ outputs_to_watch,
+
+ onchain_tx_handler,
+
+ lockdown_from_offchain: false,
+ holder_tx_signed: false,
+
+ last_block_hash: Default::default(),
+ secp_ctx: Secp256k1::new(),
+ }
+ }
+
+ /// 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
+ /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
+ fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
+ if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
+ return Err(MonitorUpdateError("Previous secret did not match new one"));
+ }
+
+ // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
+ // events for now-revoked/fulfilled HTLCs.
+ if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
+ for &mut (_, ref mut source) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
+ *source = None;
+ }
+ }
+
+ if !self.payment_preimages.is_empty() {
+ let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
+ let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
+ let min_idx = self.get_min_seen_secret();
+ let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
+
+ self.payment_preimages.retain(|&k, _| {
+ for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
+ if k == htlc.payment_hash {
+ return true
+ }
+ }
+ if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
+ for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
+ if k == htlc.payment_hash {
+ return true
+ }
+ }
+ }
+ let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
+ if *cn < min_idx {
+ return true
+ }
+ true
+ } else { false };
+ if contains {
+ counterparty_hash_commitment_number.remove(&k);
+ }
+ false
+ });
+ }
+
+ Ok(())
+ }
+
+ /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
+ /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
+ /// possibly future revocation/preimage information) to claim outputs where possible.
+ /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
+ pub(crate) fn provide_latest_counterparty_commitment_tx_info<L: Deref>(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>, commitment_number: u64, their_revocation_point: PublicKey, logger: &L) where L::Target: Logger {
+ // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
+ // so that a remote monitor doesn't learn anything unless there is a malicious close.
+ // (only maybe, sadly we cant do the same for local info, as we need to be aware of
+ // timeouts)
+ for &(ref htlc, _) in &htlc_outputs {
+ self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
+ }
+
+ let new_txid = unsigned_commitment_tx.txid();
+ log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
+ log_trace!(logger, "New potential counterparty commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
+ self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
+ self.current_counterparty_commitment_txid = Some(new_txid);
+ self.counterparty_claimable_outpoints.insert(new_txid, htlc_outputs.clone());
+ self.current_counterparty_commitment_number = commitment_number;
+ //TODO: Merge this into the other per-counterparty-transaction output storage stuff
+ match self.their_cur_revocation_points {
+ Some(old_points) => {
+ if old_points.0 == commitment_number + 1 {
+ self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
+ } else if old_points.0 == commitment_number + 2 {
+ if let Some(old_second_point) = old_points.2 {
+ self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
+ } else {
+ self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
+ }
+ } else {
+ self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
+ }
+ },
+ None => {
+ self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
+ }
+ }
+ let mut htlcs = Vec::with_capacity(htlc_outputs.len());
+ for htlc in htlc_outputs {
+ if htlc.0.transaction_output_index.is_some() {
+ htlcs.push(htlc.0);
+ }
+ }
+ self.counterparty_tx_cache.per_htlc.insert(new_txid, htlcs);
+ }
+
+ /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
+ /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
+ /// is important that any clones of this channel monitor (including remote clones) by kept
+ /// up-to-date as our holder commitment transaction is updated.
+ /// Panics if set_on_holder_tx_csv has never been called.
+ fn provide_latest_holder_commitment_tx_info(&mut self, commitment_tx: HolderCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
+ let txid = commitment_tx.txid();
+ let sequence = commitment_tx.unsigned_tx.input[0].sequence as u64;
+ let locktime = commitment_tx.unsigned_tx.lock_time as u64;
+ let mut new_holder_commitment_tx = HolderSignedTx {
+ txid,
+ revocation_key: commitment_tx.keys.revocation_key,
+ a_htlc_key: commitment_tx.keys.broadcaster_htlc_key,
+ b_htlc_key: commitment_tx.keys.countersignatory_htlc_key,
+ delayed_payment_key: commitment_tx.keys.broadcaster_delayed_payment_key,
+ per_commitment_point: commitment_tx.keys.per_commitment_point,
+ feerate_per_kw: commitment_tx.feerate_per_kw,
+ htlc_outputs: htlc_outputs,
+ };
+ self.onchain_tx_handler.provide_latest_holder_tx(commitment_tx);
+ self.current_holder_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
+ mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
+ self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
+ if self.holder_tx_signed {
+ return Err(MonitorUpdateError("Latest holder commitment signed has already been signed, update is rejected"));
+ }
+ Ok(())
+ }
+
+ /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
+ /// commitment_tx_infos which contain the payment hash have been revoked.
+ pub(crate) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
+ self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
+ }
+
+ pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
+ where B::Target: BroadcasterInterface,
+ L::Target: Logger,
+ {
+ for tx in self.get_latest_holder_commitment_txn(logger).iter() {
+ broadcaster.broadcast_transaction(tx);
+ }
+ self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
+ }
+
+ /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
+ /// itself.
+ ///
+ /// panics if the given update is not the next update by update_id.
+ pub fn update_monitor<B: Deref, L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B, logger: &L) -> Result<(), MonitorUpdateError>
+ where B::Target: BroadcasterInterface,
+ L::Target: Logger,
+ {
+ if self.latest_update_id + 1 != updates.update_id {
+ panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
+ }
+ for update in updates.updates.drain(..) {
+ match update {
+ ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs } => {
+ if self.lockdown_from_offchain { panic!(); }
+ self.provide_latest_holder_commitment_tx_info(commitment_tx, htlc_outputs)?
+ },
+ ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
+ self.provide_latest_counterparty_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
+ ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
+ self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
+ ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
+ self.provide_secret(idx, secret)?,
+ ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
+ self.lockdown_from_offchain = true;
+ if should_broadcast {
+ self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
+ } else {
+ log_error!(logger, "You have a toxic holder commitment transaction avaible in channel monitor, read comment in ChannelMonitor::get_latest_holder_commitment_txn to be informed of manual action to take");
+ }
+ }
+ }
+ }
+ self.latest_update_id = updates.update_id;
+ Ok(())
+ }
+
+ /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
+ /// ChannelMonitor.
+ pub fn get_latest_update_id(&self) -> u64 {
+ self.latest_update_id
+ }
+
+ /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
+ pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
+ &self.funding_info
+ }
+
+ /// Gets a list of txids, with their output scripts (in the order they appear in the
+ /// transaction), which we must learn about spends of via block_connected().
+ ///
+ /// (C-not exported) because we have no HashMap bindings
+ pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<Script>> {
+ &self.outputs_to_watch
+ }
+
+ /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
+ /// Generally useful when deserializing as during normal operation the return values of
+ /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
+ /// that the get_funding_txo outpoint and transaction must also be monitored for!).
+ ///
+ /// (C-not exported) as there is no practical way to track lifetimes of returned values.
+ pub fn get_monitored_outpoints(&self) -> Vec<(Txid, u32, &Script)> {
+ let mut res = Vec::with_capacity(self.counterparty_commitment_txn_on_chain.len() * 2);
+ for (ref txid, &(_, ref outputs)) in self.counterparty_commitment_txn_on_chain.iter() {
+ for (idx, output) in outputs.iter().enumerate() {
+ res.push(((*txid).clone(), idx as u32, output));
+ }
+ }
+ res
+ }
+
+ /// Get the list of HTLCs who's status has been updated on chain. This should be called by
+ /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
+ ///
+ /// [`chain::Watch::release_pending_monitor_events`]: ../trait.Watch.html#tymethod.release_pending_monitor_events
+ pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
+ let mut ret = Vec::new();
+ mem::swap(&mut ret, &mut self.pending_monitor_events);
+ ret
+ }
+
+ /// Gets the list of pending events which were generated by previous actions, clearing the list
+ /// in the process.
+ ///
+ /// This is called by ChainMonitor::get_and_clear_pending_events() and is equivalent to
+ /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
+ /// no internal locking in ChannelMonitors.
+ pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
+ let mut ret = Vec::new();
+ mem::swap(&mut ret, &mut self.pending_events);
+ ret
+ }
+
+ /// Can only fail if idx is < get_min_seen_secret
+ fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
+ self.commitment_secrets.get_secret(idx)
+ }
+
+ pub(crate) fn get_min_seen_secret(&self) -> u64 {
+ self.commitment_secrets.get_min_seen_secret()
+ }
+
+ pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
+ self.current_counterparty_commitment_number
+ }
+
+ pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
+ self.current_holder_commitment_number
+ }
+
+ /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
+ /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
+ /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
+ /// HTLC-Success/HTLC-Timeout transactions.
+ /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
+ /// revoked counterparty commitment tx
+ fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
+ // Most secp and related errors trying to create keys means we have no hope of constructing
+ // a spend transaction...so we return no transactions to broadcast
+ let mut claimable_outpoints = Vec::new();
+ let mut watch_outputs = Vec::new();
+
+ let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
+ let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
+
+ macro_rules! ignore_error {
+ ( $thing : expr ) => {
+ match $thing {
+ Ok(a) => a,
+ Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
+ }
+ };
+ }
+
+ let commitment_number = 0xffffffffffff - ((((tx.input[0].sequence as u64 & 0xffffff) << 3*8) | (tx.lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
+ if commitment_number >= self.get_min_seen_secret() {
+ let secret = self.get_secret(commitment_number).unwrap();
+ let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
+ let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
+ let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
+ let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.counterparty_tx_cache.counterparty_delayed_payment_base_key));
+
+ let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_tx_cache.on_counterparty_tx_csv, &delayed_key);
+ let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
+
+ // First, process non-htlc outputs (to_holder & to_counterparty)
+ for (idx, outp) in tx.output.iter().enumerate() {
+ if outp.script_pubkey == revokeable_p2wsh {
+ let witness_data = InputMaterial::Revoked { per_commitment_point, counterparty_delayed_payment_base_key: self.counterparty_tx_cache.counterparty_delayed_payment_base_key, counterparty_htlc_base_key: self.counterparty_tx_cache.counterparty_htlc_base_key, per_commitment_key, input_descriptor: InputDescriptors::RevokedOutput, amount: outp.value, htlc: None, on_counterparty_tx_csv: self.counterparty_tx_cache.on_counterparty_tx_csv};
+ claimable_outpoints.push(ClaimRequest { absolute_timelock: height + self.counterparty_tx_cache.on_counterparty_tx_csv as u32, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 }, witness_data});
+ }
+ }
+
+ // Then, try to find revoked htlc outputs
+ if let Some(ref per_commitment_data) = per_commitment_option {
+ for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
+ if let Some(transaction_output_index) = htlc.transaction_output_index {
+ if transaction_output_index as usize >= tx.output.len() ||
+ tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
+ return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
+ }
+ let witness_data = InputMaterial::Revoked { per_commitment_point, counterparty_delayed_payment_base_key: self.counterparty_tx_cache.counterparty_delayed_payment_base_key, counterparty_htlc_base_key: self.counterparty_tx_cache.counterparty_htlc_base_key, per_commitment_key, input_descriptor: if htlc.offered { InputDescriptors::RevokedOfferedHTLC } else { InputDescriptors::RevokedReceivedHTLC }, amount: tx.output[transaction_output_index as usize].value, htlc: Some(htlc.clone()), on_counterparty_tx_csv: self.counterparty_tx_cache.on_counterparty_tx_csv};
+ claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
+ }
+ }
+ }
+
+ // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
+ if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
+ // We're definitely a counterparty commitment transaction!
+ log_trace!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
+ watch_outputs.append(&mut tx.output.clone());
+ self.counterparty_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
+
+ 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 {
+ 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), $commitment_tx, height + ANTI_REORG_DELAY - 1);
+ match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
+ hash_map::Entry::Occupied(mut entry) => {
+ let e = entry.get_mut();
+ e.retain(|ref event| {
+ match **event {
+ OnchainEvent::HTLCUpdate { ref htlc_update } => {
+ return htlc_update.0 != **source
+ },
+ _ => true
+ }
+ });
+ e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
+ }
+ hash_map::Entry::Vacant(entry) => {
+ entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+ if let Some(ref txid) = self.current_counterparty_commitment_txid {
+ check_htlc_fails!(txid, "current");
+ }
+ if let Some(ref txid) = self.prev_counterparty_commitment_txid {
+ check_htlc_fails!(txid, "counterparty");
+ }
+ // No need to check holder commitment txn, symmetric HTLCSource must be present as per-htlc data on counterparty commitment tx
+ }
+ } else if let Some(per_commitment_data) = per_commitment_option {
+ // While this isn't useful yet, there is a potential race where if a counterparty
+ // revokes a state at the same time as the commitment transaction for that state is
+ // confirmed, and the watchtower receives the block before the user, the user could
+ // upload a new ChannelMonitor with the revocation secret but the watchtower has
+ // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
+ // not being generated by the above conditional. Thus, to be safe, we go ahead and
+ // insert it here.
+ watch_outputs.append(&mut tx.output.clone());
+ self.counterparty_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
+
+ log_trace!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
+
+ macro_rules! check_htlc_fails {
+ ($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);
+ match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
+ hash_map::Entry::Occupied(mut entry) => {
+ let e = entry.get_mut();
+ e.retain(|ref event| {
+ match **event {
+ OnchainEvent::HTLCUpdate { ref htlc_update } => {
+ return htlc_update.0 != **source
+ },
+ _ => true
+ }
+ });
+ e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
+ }
+ hash_map::Entry::Vacant(entry) => {
+ entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+ 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);
+ }
+
+ if let Some(revocation_points) = self.their_cur_revocation_points {
+ let revocation_point_option =
+ if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
+ else if let Some(point) = revocation_points.2.as_ref() {
+ if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
+ } else { None };
+ if let Some(revocation_point) = revocation_point_option {
+ self.counterparty_payment_script = {
+ // Note that the Network here is ignored as we immediately drop the address for the
+ // script_pubkey version
+ let payment_hash160 = WPubkeyHash::hash(&self.keys.pubkeys().payment_point.serialize());
+ Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script()
+ };
+
+ // Then, try to find htlc outputs
+ for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
+ if let Some(transaction_output_index) = htlc.transaction_output_index {
+ if transaction_output_index as usize >= tx.output.len() ||
+ tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
+ return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
+ }
+ let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
+ let aggregable = if !htlc.offered { false } else { true };
+ if preimage.is_some() || !htlc.offered {
+ let witness_data = InputMaterial::CounterpartyHTLC { per_commitment_point: *revocation_point, counterparty_delayed_payment_base_key: self.counterparty_tx_cache.counterparty_delayed_payment_base_key, counterparty_htlc_base_key: self.counterparty_tx_cache.counterparty_htlc_base_key, preimage, htlc: htlc.clone() };
+ claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
+ }
+ }
+ }
+ }
+ }
+ }
+ (claimable_outpoints, (commitment_txid, watch_outputs))
+ }
+
+ /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
+ fn check_spend_counterparty_htlc<L: Deref>(&mut self, tx: &Transaction, commitment_number: u64, height: u32, logger: &L) -> (Vec<ClaimRequest>, Option<(Txid, Vec<TxOut>)>) where L::Target: Logger {
+ let htlc_txid = tx.txid();
+ if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
+ return (Vec::new(), None)
+ }
+
+ macro_rules! ignore_error {
+ ( $thing : expr ) => {
+ match $thing {
+ Ok(a) => a,
+ Err(_) => return (Vec::new(), None)
+ }
+ };
+ }
+
+ let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
+ let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
+ let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
+
+ log_trace!(logger, "Counterparty HTLC broadcast {}:{}", htlc_txid, 0);
+ let witness_data = InputMaterial::Revoked { per_commitment_point, counterparty_delayed_payment_base_key: self.counterparty_tx_cache.counterparty_delayed_payment_base_key, counterparty_htlc_base_key: self.counterparty_tx_cache.counterparty_htlc_base_key, per_commitment_key, input_descriptor: InputDescriptors::RevokedOutput, amount: tx.output[0].value, htlc: None, on_counterparty_tx_csv: self.counterparty_tx_cache.on_counterparty_tx_csv };
+ let claimable_outpoints = vec!(ClaimRequest { absolute_timelock: height + self.counterparty_tx_cache.on_counterparty_tx_csv as u32, aggregable: true, outpoint: BitcoinOutPoint { txid: htlc_txid, vout: 0}, witness_data });
+ (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
+ }
+
+ fn broadcast_by_holder_state(&self, commitment_tx: &Transaction, holder_tx: &HolderSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, PublicKey, PublicKey)>) {
+ let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
+ let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
+
+ let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
+ let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
+
+ for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
+ if let Some(transaction_output_index) = htlc.transaction_output_index {
+ claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: holder_tx.txid, vout: transaction_output_index as u32 },
+ witness_data: InputMaterial::HolderHTLC {
+ preimage: if !htlc.offered {
+ if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
+ Some(preimage.clone())
+ } else {
+ // We can't build an HTLC-Success transaction without the preimage
+ continue;
+ }
+ } else { None },
+ amount: htlc.amount_msat,
+ }});
+ watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
+ }
+ }
+
+ (claim_requests, watch_outputs, broadcasted_holder_revokable_script)
+ }
+
+ /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
+ /// revoked using data in holder_claimable_outpoints.
+ /// Should not be used if check_spend_revoked_transaction succeeds.
+ fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
+ let commitment_txid = tx.txid();
+ let mut claim_requests = Vec::new();
+ let mut watch_outputs = Vec::new();
+
+ macro_rules! wait_threshold_conf {
+ ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
+ log_trace!(logger, "Failing HTLC with payment_hash {} from {} holder commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
+ match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
+ hash_map::Entry::Occupied(mut entry) => {
+ let e = entry.get_mut();
+ e.retain(|ref event| {
+ match **event {
+ OnchainEvent::HTLCUpdate { ref htlc_update } => {
+ return htlc_update.0 != $source
+ },
+ _ => true
+ }
+ });
+ e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
+ }
+ hash_map::Entry::Vacant(entry) => {
+ entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
+ }
+ }
+ }
+ }
+
+ macro_rules! append_onchain_update {
+ ($updates: expr) => {
+ claim_requests = $updates.0;
+ watch_outputs.append(&mut $updates.1);
+ self.broadcasted_holder_revokable_script = $updates.2;
+ }
+ }
+
+ // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
+ let mut is_holder_tx = false;
+
+ if self.current_holder_commitment_tx.txid == commitment_txid {
+ is_holder_tx = true;
+ log_trace!(logger, "Got latest holder commitment tx broadcast, searching for available HTLCs to claim");
+ let mut res = self.broadcast_by_holder_state(tx, &self.current_holder_commitment_tx);
+ append_onchain_update!(res);
+ } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
+ if holder_tx.txid == commitment_txid {
+ is_holder_tx = true;
+ log_trace!(logger, "Got previous holder commitment tx broadcast, searching for available HTLCs to claim");
+ let mut res = self.broadcast_by_holder_state(tx, holder_tx);
+ append_onchain_update!(res);
+ }
+ }
+
+ macro_rules! fail_dust_htlcs_after_threshold_conf {
+ ($holder_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 {
+ wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
+ }
+ }
+ }
+ }
+ }
+
+ if is_holder_tx {
+ fail_dust_htlcs_after_threshold_conf!(self.current_holder_commitment_tx);
+ if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
+ fail_dust_htlcs_after_threshold_conf!(holder_tx);
+ }
+ }
+
+ (claim_requests, (commitment_txid, watch_outputs))
+ }
+
+ /// 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
+ /// a higher revocation secret than the holder commitment number we are aware of. Broadcasting these
+ /// transactions are UNSAFE, as they allow counterparty side to punish you. Nevertheless you may want to
+ /// broadcast them if counterparty don't close channel with his higher commitment transaction after a
+ /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
+ /// out-of-band the other node operator to coordinate with him if option is available to you.
+ /// In any-case, choice is up to the user.
+ pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
+ log_trace!(logger, "Getting signed latest holder commitment transaction!");
+ self.holder_tx_signed = true;
+ if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript) {
+ let txid = commitment_tx.txid();
+ let mut res = vec![commitment_tx];
+ for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
+ if let Some(vout) = htlc.0.transaction_output_index {
+ let preimage = if !htlc.0.offered {
+ if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
+ // We can't build an HTLC-Success transaction without the preimage
+ continue;
+ }
+ } else { None };
+ if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
+ &::bitcoin::OutPoint { txid, vout }, &preimage) {
+ res.push(htlc_tx);
+ }
+ }
+ }
+ // We throw away the generated waiting_first_conf data as we aren't (yet) confirmed and we don't actually know what the caller wants to do.
+ // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
+ return res
+ }
+ Vec::new()
+ }
+
+ /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
+ /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
+ /// revoked commitment transaction.
+ #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
+ pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
+ log_trace!(logger, "Getting signed copy of latest holder commitment transaction!");
+ if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript) {
+ let txid = commitment_tx.txid();
+ let mut res = vec![commitment_tx];
+ for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
+ if let Some(vout) = htlc.0.transaction_output_index {
+ let preimage = if !htlc.0.offered {
+ if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
+ // We can't build an HTLC-Success transaction without the preimage
+ continue;
+ }
+ } else { None };
+ if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
+ &::bitcoin::OutPoint { txid, vout }, &preimage) {
+ res.push(htlc_tx);
+ }
+ }
+ }
+ return res
+ }
+ Vec::new()
+ }
+
+ /// Processes transactions in a newly connected block, which may result in any of the following:
+ /// - update the monitor's state against resolved HTLCs
+ /// - punish the counterparty in the case of seeing a revoked commitment transaction
+ /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
+ /// - detect settled outputs for later spending
+ /// - schedule and bump any in-flight claims
+ ///
+ /// Returns any new outputs to watch from `txdata`; after called, these are also included in
+ /// [`get_outputs_to_watch`].
+ ///
+ /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
+ pub fn block_connected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, txdata: &TransactionData, height: u32, broadcaster: B, fee_estimator: F, logger: L)-> Vec<(Txid, Vec<TxOut>)>
+ where B::Target: BroadcasterInterface,
+ F::Target: FeeEstimator,
+ L::Target: Logger,
+ {
+ let txn_matched = self.filter_block(txdata);
+ for tx in &txn_matched {
+ let mut output_val = 0;
+ for out in tx.output.iter() {
+ if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
+ output_val += out.value;
+ if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
+ }
+ }
+
+ let block_hash = header.block_hash();
+ log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
+
+ let mut watch_outputs = Vec::new();
+ let mut claimable_outpoints = Vec::new();
+ for tx in &txn_matched {
+ if tx.input.len() == 1 {
+ // Assuming our keys were not leaked (in which case we're screwed no matter what),
+ // commitment transactions and HTLC transactions will all only ever have one input,
+ // which is an easy way to filter out any potential non-matching txn for lazy
+ // filters.
+ let prevout = &tx.input[0].previous_output;
+ if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
+ if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
+ let (mut new_outpoints, new_outputs) = self.check_spend_counterparty_transaction(&tx, height, &logger);
+ if !new_outputs.1.is_empty() {
+ watch_outputs.push(new_outputs);
+ }
+ if new_outpoints.is_empty() {
+ let (mut new_outpoints, new_outputs) = self.check_spend_holder_transaction(&tx, height, &logger);
+ if !new_outputs.1.is_empty() {
+ watch_outputs.push(new_outputs);
+ }
+ claimable_outpoints.append(&mut new_outpoints);
+ }
+ claimable_outpoints.append(&mut new_outpoints);
+ }
+ } else {
+ if let Some(&(commitment_number, _)) = self.counterparty_commitment_txn_on_chain.get(&prevout.txid) {
+ let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(&tx, commitment_number, height, &logger);
+ claimable_outpoints.append(&mut new_outpoints);
+ if let Some(new_outputs) = new_outputs_option {
+ watch_outputs.push(new_outputs);
+ }
+ }
+ }
+ }
+ // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
+ // can also be resolved in a few other ways which can have more than one output. Thus,
+ // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
+ self.is_resolving_htlc_output(&tx, height, &logger);
+
+ self.is_paying_spendable_output(&tx, height, &logger);
+ }
+ let should_broadcast = self.would_broadcast_at_height(height, &logger);
+ if should_broadcast {
+ claimable_outpoints.push(ClaimRequest { absolute_timelock: height, aggregable: false, outpoint: BitcoinOutPoint { txid: self.funding_info.0.txid.clone(), vout: self.funding_info.0.index as u32 }, witness_data: InputMaterial::Funding { funding_redeemscript: self.funding_redeemscript.clone() }});
+ }
+ if should_broadcast {
+ self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
+ if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript) {
+ self.holder_tx_signed = true;
+ let (mut new_outpoints, new_outputs, _) = self.broadcast_by_holder_state(&commitment_tx, &self.current_holder_commitment_tx);
+ if !new_outputs.is_empty() {
+ watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
+ }
+ claimable_outpoints.append(&mut new_outpoints);
+ }
+ }
+ if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
+ for ev in events {
+ match ev {
+ OnchainEvent::HTLCUpdate { htlc_update } => {
+ log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
+ self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
+ payment_hash: htlc_update.1,
+ payment_preimage: None,
+ source: htlc_update.0,
+ }));
+ },
+ OnchainEvent::MaturingOutput { descriptor } => {
+ log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
+ self.pending_events.push(Event::SpendableOutputs {
+ outputs: vec![descriptor]
+ });
+ }
+ }
+ }
+ }
+
+ self.onchain_tx_handler.block_connected(&txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator, &*logger);
+ self.last_block_hash = block_hash;
+
+ // Determine new outputs to watch by comparing against previously known outputs to watch,
+ // updating the latter in the process.
+ watch_outputs.retain(|&(ref txid, ref txouts)| {
+ let output_scripts = txouts.iter().map(|o| o.script_pubkey.clone()).collect();
+ self.outputs_to_watch.insert(txid.clone(), output_scripts).is_none()
+ });
+ watch_outputs
+ }
+
+ /// Determines if the disconnected block contained any transactions of interest and updates
+ /// appropriately.
+ pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
+ where B::Target: BroadcasterInterface,
+ F::Target: FeeEstimator,
+ L::Target: Logger,
+ {
+ let block_hash = header.block_hash();
+ log_trace!(logger, "Block {} at height {} disconnected", block_hash, height);
+
+ if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
+ //We may discard:
+ //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
+ //- maturing spendable output has transaction paying us has been disconnected
+ }
+
+ self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
+
+ self.last_block_hash = block_hash;
+ }
+
+ /// Filters a block's `txdata` for transactions spending watched outputs or for any child
+ /// transactions thereof.
+ fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
+ let mut matched_txn = HashSet::new();
+ txdata.iter().filter(|&&(_, tx)| {
+ let mut matches = self.spends_watched_output(tx);
+ for input in tx.input.iter() {
+ if matches { break; }
+ if matched_txn.contains(&input.previous_output.txid) {
+ matches = true;
+ }
+ }
+ if matches {
+ matched_txn.insert(tx.txid());
+ }
+ matches
+ }).map(|(_, tx)| *tx).collect()
+ }
+
+ /// Checks if a given transaction spends any watched outputs.
+ fn spends_watched_output(&self, tx: &Transaction) -> bool {
+ for input in tx.input.iter() {
+ if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
+ for (idx, _script_pubkey) in outputs.iter().enumerate() {
+ if idx == input.previous_output.vout as usize {
+ return true;
+ }
+ }
+ }
+ }
+
+ false
+ }
+
+ fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
+ // We need to consider all HTLCs which are:
+ // * in any unrevoked counterparty commitment transaction, as they could broadcast said
+ // transactions and we'd end up in a race, or
+ // * are in our latest holder commitment transaction, as this is the thing we will
+ // broadcast if we go on-chain.
+ // Note that we consider HTLCs which were below dust threshold here - while they don't
+ // strictly imply that we need to fail the channel, we need to go ahead and fail them back
+ // to the source, and if we don't fail the channel we will have to ensure that the next
+ // updates that peer sends us are update_fails, failing the channel if not. It's probably
+ // easier to just fail the channel as this case should be rare enough anyway.
+ macro_rules! scan_commitment {
+ ($htlcs: expr, $holder_tx: expr) => {
+ for ref htlc in $htlcs {
+ // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
+ // chain with enough room to claim the HTLC without our counterparty being able to
+ // time out the HTLC first.
+ // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
+ // concern is being able to claim the corresponding inbound HTLC (on another
+ // channel) before it expires. In fact, we don't even really care if our
+ // counterparty here claims such an outbound HTLC after it expired as long as we
+ // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
+ // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
+ // we give ourselves a few blocks of headroom after expiration before going
+ // on-chain for an expired HTLC.
+ // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
+ // from us until we've reached the point where we go on-chain with the
+ // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
+ // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
+ // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
+ // inbound_cltv == height + CLTV_CLAIM_BUFFER
+ // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
+ // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
+ // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
+ // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
+ // The final, above, condition is checked for statically in channelmanager
+ // with CHECK_CLTV_EXPIRY_SANITY_2.
+ let htlc_outbound = $holder_tx == htlc.offered;
+ if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
+ (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
+ log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
+ return true;
+ }
+ }
+ }
+ }
+
+ scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
+
+ if let Some(ref txid) = self.current_counterparty_commitment_txid {
+ if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
+ scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
+ }
+ }
+ if let Some(ref txid) = self.prev_counterparty_commitment_txid {
+ if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
+ scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
+ }
+ }
+
+ false
+ }
+
+ /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
+ /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
+ fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
+ 'outer_loop: for input in &tx.input {
+ let mut payment_data = None;
+ let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
+ || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
+ let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
+ let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
+
+ macro_rules! log_claim {
+ ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
+ // We found the output in question, but aren't failing it backwards
+ // as we have no corresponding source and no valid counterparty commitment txid
+ // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
+ // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
+ let outbound_htlc = $holder_tx == $htlc.offered;
+ if ($holder_tx && revocation_sig_claim) ||
+ (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
+ log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
+ $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
+ if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
+ if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
+ } else {
+ log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
+ $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
+ if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
+ if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
+ }
+ }
+ }
+
+ macro_rules! check_htlc_valid_counterparty {
+ ($counterparty_txid: expr, $htlc_output: expr) => {
+ if let Some(txid) = $counterparty_txid {
+ for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
+ if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
+ if let &Some(ref source) = pending_source {
+ log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
+ payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
+ break;
+ }
+ }
+ }
+ }
+ }
+ }
+
+ macro_rules! scan_commitment {
+ ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
+ for (ref htlc_output, source_option) in $htlcs {
+ if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
+ if let Some(ref source) = source_option {
+ log_claim!($tx_info, $holder_tx, htlc_output, true);
+ // We have a resolution of an HTLC either from one of our latest
+ // holder commitment transactions or an unrevoked counterparty commitment
+ // transaction. This implies we either learned a preimage, the HTLC
+ // has timed out, or we screwed up. In any case, we should now
+ // resolve the source HTLC with the original sender.
+ payment_data = Some(((*source).clone(), htlc_output.payment_hash));
+ } else if !$holder_tx {
+ check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
+ if payment_data.is_none() {
+ check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
+ }
+ }
+ if payment_data.is_none() {
+ log_claim!($tx_info, $holder_tx, htlc_output, false);
+ continue 'outer_loop;
+ }
+ }
+ }
+ }
+ }
+
+ if input.previous_output.txid == self.current_holder_commitment_tx.txid {
+ scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
+ "our latest holder commitment tx", true);
+ }
+ if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
+ if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
+ scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
+ "our previous holder commitment tx", true);
+ }
+ }
+ if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
+ scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
+ "counterparty commitment tx", false);
+ }
+
+ // Check that scan_commitment, above, decided there is some source worth relaying an
+ // HTLC resolution backwards to and figure out whether we learned a preimage from it.
+ if let Some((source, payment_hash)) = payment_data {
+ let mut payment_preimage = PaymentPreimage([0; 32]);
+ if accepted_preimage_claim {
+ if !self.pending_monitor_events.iter().any(
+ |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
+ payment_preimage.0.copy_from_slice(&input.witness[3]);
+ self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
+ source,
+ payment_preimage: Some(payment_preimage),
+ payment_hash
+ }));
+ }
+ } else if offered_preimage_claim {
+ if !self.pending_monitor_events.iter().any(
+ |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
+ upd.source == source
+ } else { false }) {
+ payment_preimage.0.copy_from_slice(&input.witness[1]);
+ self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
+ source,
+ payment_preimage: Some(payment_preimage),
+ payment_hash
+ }));
+ }
+ } else {
+ log_info!(logger, "Failing HTLC with payment_hash {} timeout by a spend tx, waiting for confirmation (at height{})", log_bytes!(payment_hash.0), height + ANTI_REORG_DELAY - 1);
+ match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
+ hash_map::Entry::Occupied(mut entry) => {
+ let e = entry.get_mut();
+ e.retain(|ref event| {
+ match **event {
+ OnchainEvent::HTLCUpdate { ref htlc_update } => {
+ return htlc_update.0 != source
+ },
+ _ => true
+ }
+ });
+ e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
+ }
+ hash_map::Entry::Vacant(entry) => {
+ entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
+ }
+ }
+ }
+ }
+ }
+ }
+
+ /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
+ fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
+ let mut spendable_output = None;
+ for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
+ if i > ::std::u16::MAX as usize {
+ // While it is possible that an output exists on chain which is greater than the
+ // 2^16th output in a given transaction, this is only possible if the output is not
+ // in a lightning transaction and was instead placed there by some third party who
+ // wishes to give us money for no reason.
+ // Namely, any lightning transactions which we pre-sign will never have anywhere
+ // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
+ // scripts are not longer than one byte in length and because they are inherently
+ // non-standard due to their size.
+ // Thus, it is completely safe to ignore such outputs, and while it may result in
+ // us ignoring non-lightning fund to us, that is only possible if someone fills
+ // nearly a full block with garbage just to hit this case.
+ continue;
+ }
+ if outp.script_pubkey == self.destination_script {
+ spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
+ outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
+ output: outp.clone(),
+ });
+ break;
+ } else if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
+ if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
+ spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
+ outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
+ per_commitment_point: broadcasted_holder_revokable_script.1,
+ to_self_delay: self.on_holder_tx_csv,
+ output: outp.clone(),
+ key_derivation_params: self.keys.key_derivation_params(),
+ revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
+ });
+ break;
+ }
+ } else if self.counterparty_payment_script == outp.script_pubkey {
+ spendable_output = Some(SpendableOutputDescriptor::StaticOutputCounterpartyPayment {
+ outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
+ output: outp.clone(),
+ key_derivation_params: self.keys.key_derivation_params(),
+ });
+ break;
+ } else if outp.script_pubkey == self.shutdown_script {
+ spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
+ outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
+ output: outp.clone(),
+ });
+ }
+ }
+ if let Some(spendable_output) = spendable_output {
+ log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
+ match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
+ hash_map::Entry::Occupied(mut entry) => {
+ let e = entry.get_mut();
+ e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
+ }
+ hash_map::Entry::Vacant(entry) => {
+ entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
+ }
+ }
+ }
+ }
+}
+
+const MAX_ALLOC_SIZE: usize = 64*1024;
+
+impl<ChanSigner: ChannelKeys + Readable> Readable for (BlockHash, ChannelMonitor<ChanSigner>) {
+ fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
+ macro_rules! unwrap_obj {
+ ($key: expr) => {
+ match $key {
+ Ok(res) => res,
+ Err(_) => return Err(DecodeError::InvalidValue),
+ }
+ }
+ }
+
+ let _ver: u8 = Readable::read(reader)?;
+ let min_ver: u8 = Readable::read(reader)?;
+ if min_ver > SERIALIZATION_VERSION {
+ return Err(DecodeError::UnknownVersion);
+ }
+
+ let latest_update_id: u64 = Readable::read(reader)?;
+ let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
+
+ let destination_script = Readable::read(reader)?;
+ let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
+ 0 => {
+ let revokable_address = Readable::read(reader)?;
+ let per_commitment_point = Readable::read(reader)?;
+ let revokable_script = Readable::read(reader)?;
+ Some((revokable_address, per_commitment_point, revokable_script))
+ },
+ 1 => { None },
+ _ => return Err(DecodeError::InvalidValue),
+ };
+ let counterparty_payment_script = Readable::read(reader)?;
+ let shutdown_script = Readable::read(reader)?;
+
+ let keys = Readable::read(reader)?;
+ // Technically this can fail and serialize fail a round-trip, but only for serialization of
+ // barely-init'd ChannelMonitors that we can't do anything with.
+ let outpoint = OutPoint {
+ txid: Readable::read(reader)?,
+ index: Readable::read(reader)?,
+ };
+ let funding_info = (outpoint, Readable::read(reader)?);
+ let current_counterparty_commitment_txid = Readable::read(reader)?;
+ let prev_counterparty_commitment_txid = Readable::read(reader)?;
+
+ let counterparty_tx_cache = Readable::read(reader)?;
+ let funding_redeemscript = Readable::read(reader)?;
+ let channel_value_satoshis = Readable::read(reader)?;
+
+ let their_cur_revocation_points = {
+ let first_idx = <U48 as Readable>::read(reader)?.0;
+ if first_idx == 0 {
+ None
+ } else {
+ let first_point = Readable::read(reader)?;
+ let second_point_slice: [u8; 33] = Readable::read(reader)?;
+ if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
+ Some((first_idx, first_point, None))
+ } else {
+ Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
+ }
+ }
+ };
+
+ let on_holder_tx_csv: u16 = Readable::read(reader)?;
+
+ let commitment_secrets = Readable::read(reader)?;
+
+ macro_rules! read_htlc_in_commitment {
+ () => {
+ {
+ let offered: bool = Readable::read(reader)?;
+ let amount_msat: u64 = Readable::read(reader)?;
+ let cltv_expiry: u32 = Readable::read(reader)?;
+ let payment_hash: PaymentHash = Readable::read(reader)?;
+ let transaction_output_index: Option<u32> = Readable::read(reader)?;
+
+ HTLCOutputInCommitment {
+ offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
+ }
+ }
+ }
+ }
+
+ let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
+ let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
+ for _ in 0..counterparty_claimable_outpoints_len {
+ let txid: Txid = Readable::read(reader)?;
+ let htlcs_count: u64 = Readable::read(reader)?;
+ let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
+ for _ in 0..htlcs_count {
+ htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
+ }
+ if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
+ return Err(DecodeError::InvalidValue);
+ }
+ }
+
+ let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
+ let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
+ for _ in 0..counterparty_commitment_txn_on_chain_len {
+ let txid: Txid = Readable::read(reader)?;
+ let commitment_number = <U48 as Readable>::read(reader)?.0;
+ let outputs_count = <u64 as Readable>::read(reader)?;
+ let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
+ for _ in 0..outputs_count {
+ outputs.push(Readable::read(reader)?);
+ }
+ if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
+ return Err(DecodeError::InvalidValue);
+ }
+ }
+
+ let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
+ let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
+ for _ in 0..counterparty_hash_commitment_number_len {
+ let payment_hash: PaymentHash = Readable::read(reader)?;
+ let commitment_number = <U48 as Readable>::read(reader)?.0;
+ if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
+ return Err(DecodeError::InvalidValue);
+ }
+ }
+
+ macro_rules! read_holder_tx {
+ () => {
+ {
+ let txid = Readable::read(reader)?;
+ let revocation_key = Readable::read(reader)?;
+ let a_htlc_key = Readable::read(reader)?;
+ let b_htlc_key = Readable::read(reader)?;
+ let delayed_payment_key = Readable::read(reader)?;
+ let per_commitment_point = Readable::read(reader)?;
+ let feerate_per_kw: u32 = Readable::read(reader)?;
+
+ let htlcs_len: u64 = Readable::read(reader)?;
+ let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
+ for _ in 0..htlcs_len {
+ let htlc = read_htlc_in_commitment!();
+ let sigs = match <u8 as Readable>::read(reader)? {
+ 0 => None,
+ 1 => Some(Readable::read(reader)?),
+ _ => return Err(DecodeError::InvalidValue),
+ };
+ htlcs.push((htlc, sigs, Readable::read(reader)?));
+ }
+
+ HolderSignedTx {
+ txid,
+ revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
+ htlc_outputs: htlcs
+ }
+ }
+ }
+ }
+
+ let prev_holder_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
+ 0 => None,
+ 1 => {
+ Some(read_holder_tx!())
+ },
+ _ => return Err(DecodeError::InvalidValue),
+ };
+ let current_holder_commitment_tx = read_holder_tx!();
+
+ let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
+ let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
+
+ let payment_preimages_len: u64 = Readable::read(reader)?;
+ let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
+ for _ in 0..payment_preimages_len {
+ let preimage: PaymentPreimage = Readable::read(reader)?;
+ let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
+ if let Some(_) = payment_preimages.insert(hash, preimage) {
+ return Err(DecodeError::InvalidValue);
+ }
+ }
+
+ let pending_monitor_events_len: u64 = Readable::read(reader)?;
+ let mut pending_monitor_events = Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
+ for _ in 0..pending_monitor_events_len {
+ let ev = match <u8 as Readable>::read(reader)? {
+ 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
+ 1 => MonitorEvent::CommitmentTxBroadcasted(funding_info.0),
+ _ => return Err(DecodeError::InvalidValue)
+ };
+ pending_monitor_events.push(ev);
+ }
+
+ let pending_events_len: u64 = Readable::read(reader)?;
+ let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
+ for _ in 0..pending_events_len {
+ if let Some(event) = MaybeReadable::read(reader)? {
+ pending_events.push(event);
+ }
+ }
+
+ let last_block_hash: BlockHash = Readable::read(reader)?;
+
+ let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
+ let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
+ for _ in 0..waiting_threshold_conf_len {
+ let height_target = Readable::read(reader)?;
+ let events_len: u64 = Readable::read(reader)?;
+ let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
+ for _ in 0..events_len {
+ let ev = match <u8 as Readable>::read(reader)? {
+ 0 => {
+ let htlc_source = Readable::read(reader)?;
+ let hash = Readable::read(reader)?;
+ OnchainEvent::HTLCUpdate {
+ htlc_update: (htlc_source, hash)
+ }
+ },
+ 1 => {
+ let descriptor = Readable::read(reader)?;
+ OnchainEvent::MaturingOutput {
+ descriptor
+ }
+ },
+ _ => return Err(DecodeError::InvalidValue),
+ };
+ events.push(ev);
+ }
+ onchain_events_waiting_threshold_conf.insert(height_target, events);
+ }
+
+ let outputs_to_watch_len: u64 = Readable::read(reader)?;
+ let mut outputs_to_watch = HashMap::with_capacity(cmp::min(outputs_to_watch_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<Txid>() + mem::size_of::<Vec<Script>>())));
+ for _ in 0..outputs_to_watch_len {
+ let txid = Readable::read(reader)?;
+ let outputs_len: u64 = Readable::read(reader)?;
+ let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
+ for _ in 0..outputs_len {
+ outputs.push(Readable::read(reader)?);
+ }
+ if let Some(_) = outputs_to_watch.insert(txid, outputs) {
+ return Err(DecodeError::InvalidValue);
+ }
+ }
+ let onchain_tx_handler = Readable::read(reader)?;
+
+ let lockdown_from_offchain = Readable::read(reader)?;
+ let holder_tx_signed = Readable::read(reader)?;
+
+ Ok((last_block_hash.clone(), ChannelMonitor {
+ latest_update_id,
+ commitment_transaction_number_obscure_factor,
+
+ destination_script,
+ broadcasted_holder_revokable_script,
+ counterparty_payment_script,
+ shutdown_script,
+
+ keys,
+ funding_info,
+ current_counterparty_commitment_txid,
+ prev_counterparty_commitment_txid,
+
+ counterparty_tx_cache,
+ funding_redeemscript,
+ channel_value_satoshis,
+ their_cur_revocation_points,
+
+ on_holder_tx_csv,
+
+ 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,
+
+ payment_preimages,
+ pending_monitor_events,
+ pending_events,
+
+ onchain_events_waiting_threshold_conf,
+ outputs_to_watch,
+
+ onchain_tx_handler,
+
+ lockdown_from_offchain,
+ holder_tx_signed,
+
+ last_block_hash,
+ secp_ctx: Secp256k1::new(),
+ }))
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use bitcoin::blockdata::script::{Script, Builder};
+ use bitcoin::blockdata::opcodes;
+ use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
+ use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
+ use bitcoin::util::bip143;
+ use bitcoin::hashes::Hash;
+ use bitcoin::hashes::sha256::Hash as Sha256;
+ use bitcoin::hashes::hex::FromHex;
+ use bitcoin::hash_types::Txid;
+ use hex;
+ use chain::channelmonitor::ChannelMonitor;
+ use chain::transaction::OutPoint;
+ use ln::channelmanager::{PaymentPreimage, PaymentHash};
+ use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
+ use ln::chan_utils;
+ use ln::chan_utils::{HTLCOutputInCommitment, HolderCommitmentTransaction};
+ use util::test_utils::TestLogger;
+ use bitcoin::secp256k1::key::{SecretKey,PublicKey};
+ use bitcoin::secp256k1::Secp256k1;
+ use std::sync::Arc;
+ use chain::keysinterface::InMemoryChannelKeys;
+
+ #[test]
+ fn test_prune_preimages() {
+ let secp_ctx = Secp256k1::new();
+ let logger = Arc::new(TestLogger::new());
+
+ let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
+ let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
+
+ let mut preimages = Vec::new();
+ {
+ for i in 0..20 {
+ let preimage = PaymentPreimage([i; 32]);
+ let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
+ preimages.push((preimage, hash));
+ }
+ }
+
+ macro_rules! preimages_slice_to_htlc_outputs {
+ ($preimages_slice: expr) => {
+ {
+ let mut res = Vec::new();
+ for (idx, preimage) in $preimages_slice.iter().enumerate() {
+ res.push((HTLCOutputInCommitment {
+ offered: true,
+ amount_msat: 0,
+ cltv_expiry: 0,
+ payment_hash: preimage.1.clone(),
+ transaction_output_index: Some(idx as u32),
+ }, None));
+ }
+ res
+ }
+ }
+ }
+ macro_rules! preimages_to_holder_htlcs {
+ ($preimages_slice: expr) => {
+ {
+ let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
+ let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
+ res
+ }
+ }
+ }
+
+ macro_rules! test_preimages_exist {
+ ($preimages_slice: expr, $monitor: expr) => {
+ for preimage in $preimages_slice {
+ assert!($monitor.payment_preimages.contains_key(&preimage.1));
+ }
+ }
+ }
+
+ let keys = InMemoryChannelKeys::new(
+ &secp_ctx,
+ SecretKey::from_slice(&[41; 32]).unwrap(),
+ SecretKey::from_slice(&[41; 32]).unwrap(),
+ SecretKey::from_slice(&[41; 32]).unwrap(),
+ SecretKey::from_slice(&[41; 32]).unwrap(),
+ SecretKey::from_slice(&[41; 32]).unwrap(),
+ [41; 32],
+ 0,
+ (0, 0)
+ );
+
+ // Prune with one old state and a holder commitment tx holding a few overlaps with the
+ // old state.
+ let mut monitor = ChannelMonitor::new(keys,
+ &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
+ (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
+ &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
+ &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
+ 10, Script::new(), 46, 0, HolderCommitmentTransaction::dummy());
+
+ monitor.provide_latest_holder_commitment_tx_info(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..10])).unwrap();
+ monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
+ monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
+ monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
+ monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
+ for &(ref preimage, ref hash) in preimages.iter() {
+ monitor.provide_payment_preimage(hash, preimage);
+ }
+
+ // Now provide a secret, pruning preimages 10-15
+ let mut secret = [0; 32];
+ secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
+ monitor.provide_secret(281474976710655, secret.clone()).unwrap();
+ assert_eq!(monitor.payment_preimages.len(), 15);
+ test_preimages_exist!(&preimages[0..10], monitor);
+ test_preimages_exist!(&preimages[15..20], monitor);
+
+ // Now provide a further secret, pruning preimages 15-17
+ secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
+ monitor.provide_secret(281474976710654, secret.clone()).unwrap();
+ assert_eq!(monitor.payment_preimages.len(), 13);
+ test_preimages_exist!(&preimages[0..10], monitor);
+ test_preimages_exist!(&preimages[17..20], monitor);
+
+ // Now update holder commitment tx info, pruning only element 18 as we still care about the
+ // previous commitment tx's preimages too
+ monitor.provide_latest_holder_commitment_tx_info(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..5])).unwrap();
+ secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
+ monitor.provide_secret(281474976710653, secret.clone()).unwrap();
+ assert_eq!(monitor.payment_preimages.len(), 12);
+ test_preimages_exist!(&preimages[0..10], monitor);
+ test_preimages_exist!(&preimages[18..20], monitor);
+
+ // But if we do it again, we'll prune 5-10
+ monitor.provide_latest_holder_commitment_tx_info(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..3])).unwrap();
+ secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
+ monitor.provide_secret(281474976710652, secret.clone()).unwrap();
+ assert_eq!(monitor.payment_preimages.len(), 5);
+ test_preimages_exist!(&preimages[0..5], monitor);
+ }
+
+ #[test]
+ fn test_claim_txn_weight_computation() {
+ // We test Claim txn weight, knowing that we want expected weigth and
+ // not actual case to avoid sigs and time-lock delays hell variances.
+
+ let secp_ctx = Secp256k1::new();
+ let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
+ let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
+ let mut sum_actual_sigs = 0;
+
+ macro_rules! sign_input {
+ ($sighash_parts: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
+ let htlc = HTLCOutputInCommitment {
+ offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
+ amount_msat: 0,
+ cltv_expiry: 2 << 16,
+ payment_hash: PaymentHash([1; 32]),
+ transaction_output_index: Some($idx as u32),
+ };
+ let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
+ let sighash = hash_to_message!(&$sighash_parts.signature_hash($idx, &redeem_script, $amount, SigHashType::All)[..]);
+ let sig = secp_ctx.sign(&sighash, &privkey);
+ $sighash_parts.access_witness($idx).push(sig.serialize_der().to_vec());
+ $sighash_parts.access_witness($idx)[0].push(SigHashType::All as u8);
+ sum_actual_sigs += $sighash_parts.access_witness($idx)[0].len();
+ if *$input_type == InputDescriptors::RevokedOutput {
+ $sighash_parts.access_witness($idx).push(vec!(1));
+ } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
+ $sighash_parts.access_witness($idx).push(pubkey.clone().serialize().to_vec());
+ } else if *$input_type == InputDescriptors::ReceivedHTLC {
+ $sighash_parts.access_witness($idx).push(vec![0]);
+ } else {
+ $sighash_parts.access_witness($idx).push(PaymentPreimage([1; 32]).0.to_vec());
+ }
+ $sighash_parts.access_witness($idx).push(redeem_script.into_bytes());
+ println!("witness[0] {}", $sighash_parts.access_witness($idx)[0].len());
+ println!("witness[1] {}", $sighash_parts.access_witness($idx)[1].len());
+ println!("witness[2] {}", $sighash_parts.access_witness($idx)[2].len());
+ }
+ }
+
+ let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
+ let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
+
+ // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
+ let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
+ for i in 0..4 {
+ claim_tx.input.push(TxIn {
+ previous_output: BitcoinOutPoint {
+ txid,
+ vout: i,
+ },
+ script_sig: Script::new(),
+ sequence: 0xfffffffd,
+ witness: Vec::new(),
+ });
+ }
+ claim_tx.output.push(TxOut {
+ script_pubkey: script_pubkey.clone(),
+ value: 0,
+ });
+ let base_weight = claim_tx.get_weight();
+ let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
+ {
+ let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
+ for (idx, inp) in inputs_des.iter().enumerate() {
+ sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
+ }
+ }
+ assert_eq!(base_weight + OnchainTxHandler::<InMemoryChannelKeys>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
+
+ // Claim tx with 1 offered HTLCs, 3 received HTLCs
+ claim_tx.input.clear();
+ sum_actual_sigs = 0;
+ for i in 0..4 {
+ claim_tx.input.push(TxIn {
+ previous_output: BitcoinOutPoint {
+ txid,
+ vout: i,
+ },
+ script_sig: Script::new(),
+ sequence: 0xfffffffd,
+ witness: Vec::new(),
+ });
+ }
+ let base_weight = claim_tx.get_weight();
+ let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
+ {
+ let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
+ for (idx, inp) in inputs_des.iter().enumerate() {
+ sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
+ }
+ }
+ assert_eq!(base_weight + OnchainTxHandler::<InMemoryChannelKeys>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
+
+ // Justice tx with 1 revoked HTLC-Success tx output
+ claim_tx.input.clear();
+ sum_actual_sigs = 0;
+ claim_tx.input.push(TxIn {
+ previous_output: BitcoinOutPoint {
+ txid,
+ vout: 0,
+ },
+ script_sig: Script::new(),
+ sequence: 0xfffffffd,
+ witness: Vec::new(),
+ });
+ let base_weight = claim_tx.get_weight();
+ let inputs_des = vec![InputDescriptors::RevokedOutput];
+ {
+ let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
+ for (idx, inp) in inputs_des.iter().enumerate() {
+ sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
+ }
+ }
+ assert_eq!(base_weight + OnchainTxHandler::<InMemoryChannelKeys>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_des.len() - sum_actual_sigs));
+ }
+
+ // Further testing is done in the ChannelManager integration tests.
+}
use bitcoin::blockdata::transaction::TxOut;
use bitcoin::hash_types::{BlockHash, Txid};
+use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, MonitorEvent};
use chain::keysinterface::ChannelKeys;
use chain::transaction::OutPoint;
-use chain::chainmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, MonitorEvent};
pub mod chaininterface;
+ pub mod chainmonitor;
+pub mod channelmonitor;
pub mod transaction;
pub mod keysinterface;
}
macro_rules! log_funding_info {
($key_storage: expr) => {
-- ::util::macro_logger::DebugFundingInfo(&$key_storage.funding_info)
++ ::util::macro_logger::DebugFundingInfo($key_storage.get_funding_txo())
}
}
use chain;
use chain::chaininterface;
use chain::chaininterface::ConfirmationTarget;
-use chain::chainmonitor::MonitorEvent;
+ use chain::chainmonitor;
+use chain::channelmonitor;
+use chain::channelmonitor::MonitorEvent;
use chain::transaction::OutPoint;
use chain::keysinterface;
use ln::features::{ChannelFeatures, InitFeatures};
}
pub struct TestChainMonitor<'a> {
- pub added_monitors: Mutex<Vec<(OutPoint, chainmonitor::ChannelMonitor<EnforcingChannelKeys>)>>,
+ pub added_monitors: Mutex<Vec<(OutPoint, channelmonitor::ChannelMonitor<EnforcingChannelKeys>)>>,
pub latest_monitor_update_id: Mutex<HashMap<[u8; 32], (OutPoint, u64)>>,
- pub chain_monitor: channelmonitor::ChainMonitor<EnforcingChannelKeys, &'a TestChainSource, &'a chaininterface::BroadcasterInterface, &'a TestFeeEstimator, &'a TestLogger>,
+ pub chain_monitor: chainmonitor::ChainMonitor<EnforcingChannelKeys, &'a TestChainSource, &'a chaininterface::BroadcasterInterface, &'a TestFeeEstimator, &'a TestLogger>,
- pub update_ret: Mutex<Result<(), chainmonitor::ChannelMonitorUpdateErr>>,
+ pub update_ret: Mutex<Result<(), channelmonitor::ChannelMonitorUpdateErr>>,
// If this is set to Some(), after the next return, we'll always return this until update_ret
// is changed:
- pub next_update_ret: Mutex<Option<Result<(), chainmonitor::ChannelMonitorUpdateErr>>>,
+ pub next_update_ret: Mutex<Option<Result<(), channelmonitor::ChannelMonitorUpdateErr>>>,
}
impl<'a> TestChainMonitor<'a> {
pub fn new(chain_source: Option<&'a TestChainSource>, broadcaster: &'a chaininterface::BroadcasterInterface, logger: &'a TestLogger, fee_estimator: &'a TestFeeEstimator) -> Self {
projects / rust-lightning / commitdiff