X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fchain%2Fchannelmonitor.rs;h=889dfa211ee78d167dbad2229ffcaf7dc82d1d4c;hb=9c7c3b99210676793b1d35575d8538979cc1b349;hp=d8433ef5ffaf423fbed900bbde1a017274c89c18;hpb=27ee1150dd39dc2fe72ad7f4b0a040fe510fa0da;p=rust-lightning diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs index d8433ef5..889dfa21 100644 --- a/lightning/src/chain/channelmonitor.rs +++ b/lightning/src/chain/channelmonitor.rs @@ -57,7 +57,7 @@ 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))] +#[cfg_attr(any(test, feature = "_test_utils"), derive(PartialEq))] #[derive(Clone)] #[must_use] pub struct ChannelMonitorUpdate { @@ -95,7 +95,7 @@ impl Readable for ChannelMonitorUpdate { } /// An error enum representing a failure to persist a channel monitor update. -#[derive(Clone)] +#[derive(Clone, Debug)] 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). @@ -159,7 +159,7 @@ pub enum ChannelMonitorUpdateErr { /// 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. +/// Contains a developer-readable error message. #[derive(Debug)] pub struct MonitorUpdateError(pub &'static str); @@ -470,7 +470,7 @@ enum OnchainEvent { const SERIALIZATION_VERSION: u8 = 1; const MIN_SERIALIZATION_VERSION: u8 = 1; -#[cfg_attr(test, derive(PartialEq))] +#[cfg_attr(any(test, feature = "_test_utils"), derive(PartialEq))] #[derive(Clone)] pub(crate) enum ChannelMonitorUpdateStep { LatestHolderCommitmentTXInfo { @@ -696,7 +696,7 @@ pub struct ChannelMonitor { secp_ctx: Secp256k1, //TODO: dedup this a bit... } -#[cfg(any(test, feature = "fuzztarget"))] +#[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))] /// Used only in testing and fuzztarget to check serialization roundtrips don't change the /// underlying object impl PartialEq for ChannelMonitor { @@ -746,7 +746,7 @@ impl ChannelMonitor { /// 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(&self, writer: &mut W) -> Result<(), Error> { + pub fn serialize_for_disk(&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])?; @@ -1162,28 +1162,28 @@ impl ChannelMonitor { /// itself. /// /// panics if the given update is not the next update by update_id. - pub fn update_monitor(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B, logger: &L) -> Result<(), MonitorUpdateError> + pub fn update_monitor(&mut self, 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(..) { + for update in updates.updates.iter() { 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)? + self.provide_latest_holder_commitment_tx_info(commitment_tx.clone(), htlc_outputs.clone())? }, 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), + self.provide_latest_counterparty_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs.clone(), *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)?, + self.provide_secret(*idx, *secret)?, ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => { self.lockdown_from_offchain = true; - if should_broadcast { + 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"); @@ -2123,6 +2123,61 @@ impl ChannelMonitor { } } +/// `Persist` defines behavior for persisting channel monitors: this could mean +/// writing once to disk, and/or uploading to one or more backup services. +/// +/// Note that for every new monitor, you **must** persist the new `ChannelMonitor` +/// to disk/backups. And, on every update, you **must** persist either the +/// `ChannelMonitorUpdate` or the updated monitor itself. Otherwise, there is risk +/// of situations such as revoking a transaction, then crashing before this +/// revocation can be persisted, then unintentionally broadcasting a revoked +/// transaction and losing money. This is a risk because previous channel states +/// are toxic, so it's important that whatever channel state is persisted is +/// kept up-to-date. +pub trait Persist: Send + Sync { + /// Persist a new channel's data. The data can be stored any way you want, but + /// the identifier provided by Rust-Lightning is the channel's outpoint (and + /// it is up to you to maintain a correct mapping between the outpoint and the + /// stored channel data). Note that you **must** persist every new monitor to + /// disk. See the `Persist` trait documentation for more details. + /// + /// See [`ChannelMonitor::serialize_for_disk`] for writing out a `ChannelMonitor`, + /// and [`ChannelMonitorUpdateErr`] for requirements when returning errors. + /// + /// [`ChannelMonitor::serialize_for_disk`]: struct.ChannelMonitor.html#method.serialize_for_disk + /// [`ChannelMonitorUpdateErr`]: enum.ChannelMonitorUpdateErr.html + fn persist_new_channel(&self, id: OutPoint, data: &ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>; + + /// Update one channel's data. The provided `ChannelMonitor` has already + /// applied the given update. + /// + /// Note that on every update, you **must** persist either the + /// `ChannelMonitorUpdate` or the updated monitor itself to disk/backups. See + /// the `Persist` trait documentation for more details. + /// + /// If an implementer chooses to persist the updates only, they need to make + /// sure that all the updates are applied to the `ChannelMonitors` *before* + /// the set of channel monitors is given to the `ChannelManager` + /// deserialization routine. See [`ChannelMonitor::update_monitor`] for + /// applying a monitor update to a monitor. If full `ChannelMonitors` are + /// persisted, then there is no need to persist individual updates. + /// + /// Note that there could be a performance tradeoff between persisting complete + /// channel monitors on every update vs. persisting only updates and applying + /// them in batches. The size of each monitor grows `O(number of state updates)` + /// whereas updates are small and `O(1)`. + /// + /// See [`ChannelMonitor::serialize_for_disk`] for writing out a `ChannelMonitor`, + /// [`ChannelMonitorUpdate::write`] for writing out an update, and + /// [`ChannelMonitorUpdateErr`] for requirements when returning errors. + /// + /// [`ChannelMonitor::update_monitor`]: struct.ChannelMonitor.html#impl-1 + /// [`ChannelMonitor::serialize_for_disk`]: struct.ChannelMonitor.html#method.serialize_for_disk + /// [`ChannelMonitorUpdate::write`]: struct.ChannelMonitorUpdate.html#method.write + /// [`ChannelMonitorUpdateErr`]: enum.ChannelMonitorUpdateErr.html + fn update_persisted_channel(&self, id: OutPoint, update: &ChannelMonitorUpdate, data: &ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>; +} + const MAX_ALLOC_SIZE: usize = 64*1024; impl Readable for (BlockHash, ChannelMonitor) {