X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fchain%2Fchannelmonitor.rs;h=c483d01f37d129697a25d7a369f9f4b8cddce21f;hb=2398f1746d592b7c71100a61094d7bfc9bc8f1cd;hp=413d184b598c1c01564c3f3fb9350f402b87badf;hpb=35573bb3d7bf8c7f7b9d8759afa555aec2735a44;p=rust-lightning diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs index 413d184b..c483d01f 100644 --- a/lightning/src/chain/channelmonitor.rs +++ b/lightning/src/chain/channelmonitor.rs @@ -115,67 +115,6 @@ impl Readable for ChannelMonitorUpdate { } } -/// An error enum representing a failure to persist a channel monitor update. -#[derive(Clone, Copy, Debug, PartialEq)] -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 @@ -190,8 +129,8 @@ pub enum MonitorEvent { /// A monitor event containing an HTLCUpdate. HTLCEvent(HTLCUpdate), - /// A monitor event that the Channel's commitment transaction was broadcasted. - CommitmentTxBroadcasted(OutPoint), + /// A monitor event that the Channel's commitment transaction was confirmed. + CommitmentTxConfirmed(OutPoint), } /// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on @@ -918,7 +857,7 @@ impl Writeable for ChannelMonitorImpl { 0u8.write(writer)?; upd.write(writer)?; }, - MonitorEvent::CommitmentTxBroadcasted(_) => 1u8.write(writer)? + MonitorEvent::CommitmentTxConfirmed(_) => 1u8.write(writer)? } } @@ -1787,7 +1726,7 @@ impl ChannelMonitorImpl { log_info!(logger, "Broadcasting local {}", log_tx!(tx)); broadcaster.broadcast_transaction(tx); } - self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0)); + self.pending_monitor_events.push(MonitorEvent::CommitmentTxConfirmed(self.funding_info.0)); } pub fn update_monitor(&mut self, updates: &ChannelMonitorUpdate, broadcaster: &B, fee_estimator: &F, logger: &L) -> Result<(), MonitorUpdateError> @@ -1835,7 +1774,7 @@ impl ChannelMonitorImpl { } else if !self.holder_tx_signed { 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"); } else { - // If we generated a MonitorEvent::CommitmentTxBroadcasted, the ChannelManager + // If we generated a MonitorEvent::CommitmentTxConfirmed, the ChannelManager // will still give us a ChannelForceClosed event with !should_broadcast, but we // shouldn't print the scary warning above. log_info!(logger, "Channel off-chain state closed after we broadcasted our latest commitment transaction."); @@ -2357,7 +2296,7 @@ impl ChannelMonitorImpl { let funding_outp = HolderFundingOutput::build(self.funding_redeemscript.clone()); let commitment_package = PackageTemplate::build_package(self.funding_info.0.txid.clone(), self.funding_info.0.index as u32, PackageSolvingData::HolderFundingOutput(funding_outp), self.best_block.height(), false, self.best_block.height()); claimable_outpoints.push(commitment_package); - self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0)); + self.pending_monitor_events.push(MonitorEvent::CommitmentTxConfirmed(self.funding_info.0)); let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript); self.holder_tx_signed = true; // Because we're broadcasting a commitment transaction, we should construct the package @@ -2615,8 +2554,10 @@ impl ChannelMonitorImpl { 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); + #[cfg(not(fuzzing))] let accepted_timeout_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && !revocation_sig_claim; let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && !revocation_sig_claim; + #[cfg(not(fuzzing))] let offered_timeout_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::OfferedHTLC); let mut payment_preimage = PaymentPreimage([0; 32]); @@ -2875,53 +2816,6 @@ impl ChannelMonitorImpl { } } -/// `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 { - /// 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::write`] for writing out a `ChannelMonitor`, - /// and [`ChannelMonitorUpdateErr`] for requirements when returning errors. - 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::write`] for writing out a `ChannelMonitor`, - /// [`ChannelMonitorUpdate::write`] for writing out an update, and - /// [`ChannelMonitorUpdateErr`] for requirements when returning errors. - fn update_persisted_channel(&self, id: OutPoint, update: &ChannelMonitorUpdate, data: &ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>; -} - impl chain::Listen for (ChannelMonitor, T, F, L) where T::Target: BroadcasterInterface, @@ -3110,7 +3004,7 @@ impl<'a, Signer: Sign, K: KeysInterface> ReadableArgs<&'a K> for _ in 0..pending_monitor_events_len { let ev = match ::read(reader)? { 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?), - 1 => MonitorEvent::CommitmentTxBroadcasted(funding_info.0), + 1 => MonitorEvent::CommitmentTxConfirmed(funding_info.0), _ => return Err(DecodeError::InvalidValue) }; pending_monitor_events.push(ev);