X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Fchannelmonitor.rs;h=33cc869efe8aeed5168acec5aaf56d6f5ddee8d5;hb=c61b9202b6a4f51dec4146a4babb18925e4debd9;hp=6698002132e33242ac8a16ae9818f53f1aaae5b0;hpb=3aef4479925f44ed1dd688b643a22d71806705f0;p=rust-lightning diff --git a/lightning/src/ln/channelmonitor.rs b/lightning/src/ln/channelmonitor.rs index 66980021..33cc869e 100644 --- a/lightning/src/ln/channelmonitor.rs +++ b/lightning/src/ln/channelmonitor.rs @@ -149,66 +149,6 @@ pub struct HTLCUpdate { } impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source }); -/// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between -/// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing -/// events to it, while also taking any add/update_monitor events and passing them to some remote -/// server(s). -/// -/// In general, you must always have at least one local copy in memory, which must never fail to -/// update (as it is responsible for broadcasting the latest state in case the channel is closed), -/// and then persist it to various on-disk locations. If, for some reason, the in-memory copy fails -/// to update (eg out-of-memory or some other condition), you must immediately shut down without -/// taking any further action such as writing the current state to disk. This should likely be -/// accomplished via panic!() or abort(). -/// -/// Note that any updates to a channel's monitor *must* be applied to each instance of the -/// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If -/// an update occurs and a remote watchtower is left with old state, it may broadcast transactions -/// which we have revoked, allowing our counterparty to claim all funds in the channel! -/// -/// User needs to notify implementors of ManyChannelMonitor when a new block is connected or -/// disconnected using their `block_connected` and `block_disconnected` methods. However, rather -/// than calling these methods directly, the user should register implementors as listeners to the -/// BlockNotifier and call the BlockNotifier's `block_(dis)connected` methods, which will notify -/// all registered listeners in one go. -pub trait ManyChannelMonitor: Send + Sync { - /// Adds a monitor for the given `funding_txo`. - /// - /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with - /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected - /// callbacks with the funding transaction, or any spends of it. - /// - /// Further, the implementer must also ensure that each output returned in - /// monitor.get_outputs_to_watch() is registered to ensure that the provided monitor learns about - /// any spends of any of the outputs. - /// - /// Any spends of outputs which should have been registered which aren't passed to - /// ChannelMonitors via block_connected may result in FUNDS LOSS. - fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>; - - /// Updates a monitor for the given `funding_txo`. - /// - /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with - /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected - /// callbacks with the funding transaction, or any spends of it. - /// - /// Further, the implementer must also ensure that each output returned in - /// monitor.get_watch_outputs() is registered to ensure that the provided monitor learns about - /// any spends of any of the outputs. - /// - /// Any spends of outputs which should have been registered which aren't passed to - /// ChannelMonitors via block_connected may result in FUNDS LOSS. - fn update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr>; - - /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated - /// with success or failure. - /// - /// You should probably just call through to - /// ChannelMonitor::get_and_clear_pending_htlcs_updated() for each ChannelMonitor and return - /// the full list. - fn get_and_clear_pending_htlcs_updated(&self) -> Vec; -} - /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a /// watchtower or watch our own channels. /// @@ -243,27 +183,32 @@ impl = matched_indexes.iter().map(|index| txdata[*index]).collect(); + let last_seen = self.chain_monitor.reentered(); + { + let mut monitors = self.monitors.lock().unwrap(); + for monitor in monitors.values_mut() { + let txn_outputs = monitor.block_connected(header, &matched_txn, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger); + + for (ref txid, ref outputs) in txn_outputs { + for (idx, output) in outputs.iter().enumerate() { + self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey); + } } } } + reentered = last_seen != self.chain_monitor.reentered(); } } fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) { - let block_hash = header.bitcoin_hash(); let mut monitors = self.monitors.lock().unwrap(); for monitor in monitors.values_mut() { - monitor.block_disconnected(disconnected_height, &block_hash, &*self.broadcaster, &*self.fee_estimator, &*self.logger); + monitor.block_disconnected(header, disconnected_height, &*self.broadcaster, &*self.fee_estimator, &*self.logger); } } } @@ -295,12 +240,15 @@ impl return Err(MonitorUpdateError("Channel monitor for given key is already present")), hash_map::Entry::Vacant(e) => e, }; - log_trace!(self.logger, "Got new Channel Monitor for channel {}", log_bytes!(monitor.funding_info.0.to_channel_id()[..])); - self.chain_monitor.install_watch_tx(&monitor.funding_info.0.txid, &monitor.funding_info.1); - self.chain_monitor.install_watch_outpoint((monitor.funding_info.0.txid, monitor.funding_info.0.index as u32), &monitor.funding_info.1); - for (txid, outputs) in monitor.get_outputs_to_watch().iter() { - for (idx, script) in outputs.iter().enumerate() { - self.chain_monitor.install_watch_outpoint((*txid, idx as u32), script); + { + 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()[..])); + self.chain_monitor.install_watch_tx(&funding_txo.0.txid, &funding_txo.1); + self.chain_monitor.install_watch_outpoint((funding_txo.0.txid, funding_txo.0.index as u32), &funding_txo.1); + for (txid, outputs) in monitor.get_outputs_to_watch().iter() { + for (idx, script) in outputs.iter().enumerate() { + self.chain_monitor.install_watch_outpoint((*txid, idx as u32), script); + } } } entry.insert(monitor); @@ -320,12 +268,14 @@ impl ManyChannelMonitor for SimpleManyChannelMonitor +impl ManyChannelMonitor for SimpleManyChannelMonitor where T::Target: BroadcasterInterface, F::Target: FeeEstimator, L::Target: Logger, C::Target: ChainWatchInterface, { + type Keys = ChanSigner; + fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr> { match self.add_monitor_by_key(funding_txo, monitor) { Ok(_) => Ok(()), @@ -424,7 +374,7 @@ struct LocalSignedTx { b_htlc_key: PublicKey, delayed_payment_key: PublicKey, per_commitment_point: PublicKey, - feerate_per_kw: u64, + feerate_per_kw: u32, htlc_outputs: Vec<(HTLCOutputInCommitment, Option, Option)>, } @@ -438,6 +388,53 @@ struct RemoteCommitmentTransaction { per_htlc: HashMap> } +impl Writeable for RemoteCommitmentTransaction { + fn write(&self, w: &mut W) -> Result<(), ::std::io::Error> { + self.remote_delayed_payment_base_key.write(w)?; + self.remote_htlc_base_key.write(w)?; + w.write_all(&byte_utils::be16_to_array(self.on_remote_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 RemoteCommitmentTransaction { + fn read(r: &mut R) -> Result { + let remote_commitment_transaction = { + let remote_delayed_payment_base_key = Readable::read(r)?; + let remote_htlc_base_key = Readable::read(r)?; + let on_remote_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); + } + } + RemoteCommitmentTransaction { + remote_delayed_payment_base_key, + remote_htlc_base_key, + on_remote_tx_csv, + per_htlc, + } + }; + Ok(remote_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 @@ -823,6 +820,70 @@ pub struct ChannelMonitor { secp_ctx: Secp256k1, //TODO: dedup this a bit... } +/// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between +/// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing +/// events to it, while also taking any add/update_monitor events and passing them to some remote +/// server(s). +/// +/// In general, you must always have at least one local copy in memory, which must never fail to +/// update (as it is responsible for broadcasting the latest state in case the channel is closed), +/// and then persist it to various on-disk locations. If, for some reason, the in-memory copy fails +/// to update (eg out-of-memory or some other condition), you must immediately shut down without +/// taking any further action such as writing the current state to disk. This should likely be +/// accomplished via panic!() or abort(). +/// +/// Note that any updates to a channel's monitor *must* be applied to each instance of the +/// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If +/// an update occurs and a remote watchtower is left with old state, it may broadcast transactions +/// which we have revoked, allowing our counterparty to claim all funds in the channel! +/// +/// User needs to notify implementors of ManyChannelMonitor when a new block is connected or +/// disconnected using their `block_connected` and `block_disconnected` methods. However, rather +/// than calling these methods directly, the user should register implementors as listeners to the +/// BlockNotifier and call the BlockNotifier's `block_(dis)connected` methods, which will notify +/// all registered listeners in one go. +pub trait ManyChannelMonitor: Send + Sync { + /// The concrete type which signs for transactions and provides access to our channel public + /// keys. + type Keys: ChannelKeys; + + /// Adds a monitor for the given `funding_txo`. + /// + /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with + /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected + /// callbacks with the funding transaction, or any spends of it. + /// + /// Further, the implementer must also ensure that each output returned in + /// monitor.get_outputs_to_watch() is registered to ensure that the provided monitor learns about + /// any spends of any of the outputs. + /// + /// Any spends of outputs which should have been registered which aren't passed to + /// ChannelMonitors via block_connected may result in FUNDS LOSS. + fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>; + + /// Updates a monitor for the given `funding_txo`. + /// + /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with + /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected + /// callbacks with the funding transaction, or any spends of it. + /// + /// Further, the implementer must also ensure that each output returned in + /// monitor.get_watch_outputs() is registered to ensure that the provided monitor learns about + /// any spends of any of the outputs. + /// + /// Any spends of outputs which should have been registered which aren't passed to + /// ChannelMonitors via block_connected may result in FUNDS LOSS. + fn update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr>; + + /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated + /// with success or failure. + /// + /// You should probably just call through to + /// ChannelMonitor::get_and_clear_pending_htlcs_updated() for each ChannelMonitor and return + /// the full list. + fn get_and_clear_pending_htlcs_updated(&self) -> Vec; +} + #[cfg(any(test, feature = "fuzztarget"))] /// Used only in testing and fuzztarget to check serialization roundtrips don't change the /// underlying object @@ -904,17 +965,7 @@ impl ChannelMonitor { self.current_remote_commitment_txid.write(writer)?; self.prev_remote_commitment_txid.write(writer)?; - self.remote_tx_cache.remote_delayed_payment_base_key.write(writer)?; - self.remote_tx_cache.remote_htlc_base_key.write(writer)?; - writer.write_all(&byte_utils::be16_to_array(self.remote_tx_cache.on_remote_tx_csv))?; - writer.write_all(&byte_utils::be64_to_array(self.remote_tx_cache.per_htlc.len() as u64))?; - for (ref txid, ref htlcs) in self.remote_tx_cache.per_htlc.iter() { - writer.write_all(&txid[..])?; - writer.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?; - for &ref htlc in htlcs.iter() { - htlc.write(writer)?; - } - } + self.remote_tx_cache.write(writer)?; self.funding_redeemscript.write(writer)?; self.channel_value_satoshis.write(writer)?; @@ -985,7 +1036,7 @@ impl ChannelMonitor { writer.write_all(&$local_tx.delayed_payment_key.serialize())?; writer.write_all(&$local_tx.per_commitment_point.serialize())?; - writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?; + writer.write_all(&byte_utils::be32_to_array($local_tx.feerate_per_kw))?; writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?; for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() { serialize_htlc_in_commitment!(htlc_output); @@ -1365,8 +1416,8 @@ impl ChannelMonitor { } /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for. - pub fn get_funding_txo(&self) -> OutPoint { - self.funding_info.0 + 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 @@ -1598,7 +1649,7 @@ impl ChannelMonitor { self.remote_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(&PublicKey::from_secret_key(&self.secp_ctx, &self.keys.payment_key()).serialize()); + 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() }; @@ -1824,12 +1875,12 @@ impl ChannelMonitor { /// Eventually this should be pub and, roughly, implement ChainListener, however this requires /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of /// on-chain. - fn block_connected(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &BlockHash, broadcaster: B, fee_estimator: F, logger: L)-> Vec<(Txid, Vec)> + fn block_connected(&mut self, header: &BlockHeader, txn_matched: &[(usize, &Transaction)], height: u32, broadcaster: B, fee_estimator: F, logger: L)-> Vec<(Txid, Vec)> where B::Target: BroadcasterInterface, F::Target: FeeEstimator, L::Target: Logger, { - for tx in txn_matched { + 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"); } @@ -1838,10 +1889,12 @@ impl ChannelMonitor { } } + let block_hash = header.bitcoin_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 { + 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, @@ -1915,7 +1968,7 @@ impl ChannelMonitor { } self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator, &*logger); - self.last_block_hash = block_hash.clone(); + self.last_block_hash = block_hash; for &(ref txid, ref output_scripts) in watch_outputs.iter() { self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect()); } @@ -1923,12 +1976,14 @@ impl ChannelMonitor { watch_outputs } - fn block_disconnected(&mut self, height: u32, block_hash: &BlockHash, broadcaster: B, fee_estimator: F, logger: L) + fn block_disconnected(&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.bitcoin_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 @@ -1937,7 +1992,7 @@ impl ChannelMonitor { self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger); - self.last_block_hash = block_hash.clone(); + self.last_block_hash = block_hash; } pub(super) fn would_broadcast_at_height(&self, height: u32, logger: &L) -> bool where L::Target: Logger { @@ -2162,7 +2217,7 @@ impl ChannelMonitor { break; } } else if self.remote_payment_script == outp.script_pubkey { - spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WPKH { + spendable_output = Some(SpendableOutputDescriptor::StaticOutputRemotePayment { outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 }, output: outp.clone(), key_derivation_params: self.keys.key_derivation_params(), @@ -2237,31 +2292,7 @@ impl Readable for (BlockHash, ChannelMonitor let current_remote_commitment_txid = Readable::read(reader)?; let prev_remote_commitment_txid = Readable::read(reader)?; - let remote_tx_cache = { - let remote_delayed_payment_base_key = Readable::read(reader)?; - let remote_htlc_base_key = Readable::read(reader)?; - let on_remote_tx_csv: u16 = Readable::read(reader)?; - let per_htlc_len: u64 = Readable::read(reader)?; - 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(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 { - let htlc = Readable::read(reader)?; - htlcs.push(htlc); - } - if let Some(_) = per_htlc.insert(txid, htlcs) { - return Err(DecodeError::InvalidValue); - } - } - RemoteCommitmentTransaction { - remote_delayed_payment_base_key, - remote_htlc_base_key, - on_remote_tx_csv, - per_htlc, - } - }; + let remote_tx_cache = Readable::read(reader)?; let funding_redeemscript = Readable::read(reader)?; let channel_value_satoshis = Readable::read(reader)?; @@ -2348,7 +2379,7 @@ impl Readable for (BlockHash, ChannelMonitor 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: u64 = 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)); @@ -2525,7 +2556,6 @@ mod tests { use util::test_utils::TestLogger; use bitcoin::secp256k1::key::{SecretKey,PublicKey}; use bitcoin::secp256k1::Secp256k1; - use rand::{thread_rng,Rng}; use std::sync::Arc; use chain::keysinterface::InMemoryChannelKeys; @@ -2539,10 +2569,8 @@ mod tests { let mut preimages = Vec::new(); { - let mut rng = thread_rng(); - for _ in 0..20 { - let mut preimage = PaymentPreimage([0; 32]); - rng.fill_bytes(&mut preimage.0[..]); + for i in 0..20 { + let preimage = PaymentPreimage([i; 32]); let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner()); preimages.push((preimage, hash)); }