X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;ds=sidebyside;f=lightning%2Fsrc%2Fchain%2Fonchaintx.rs;h=18679f0aacd5cd34fead7952fc91be997ad4e57b;hb=f4e6d4a65307f1aaf921801d646c3c7a2e86e145;hp=f79a877553d4d6f142047d3765cdb05b0665d0af;hpb=bac1b79fbb000a9cdc615260af2275c97682c2dc;p=rust-lightning diff --git a/lightning/src/chain/onchaintx.rs b/lightning/src/chain/onchaintx.rs index f79a8775..18679f0a 100644 --- a/lightning/src/chain/onchaintx.rs +++ b/lightning/src/chain/onchaintx.rs @@ -21,23 +21,31 @@ use bitcoin::hash_types::Txid; use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature}; use bitcoin::secp256k1; -use ln::msgs::DecodeError; -use ln::PaymentPreimage; -use ln::chan_utils::{ChannelTransactionParameters, HolderCommitmentTransaction}; -use chain::chaininterface::{FeeEstimator, BroadcasterInterface, LowerBoundedFeeEstimator}; -use chain::channelmonitor::{ANTI_REORG_DELAY, CLTV_SHARED_CLAIM_BUFFER}; -use chain::keysinterface::{Sign, KeysInterface}; -use chain::package::PackageTemplate; -use util::logger::Logger; -use util::ser::{Readable, ReadableArgs, MaybeReadable, Writer, Writeable, VecWriter}; -use util::byte_utils; - -use io; -use prelude::*; +use crate::ln::msgs::DecodeError; +use crate::ln::PaymentPreimage; +#[cfg(anchors)] +use crate::ln::chan_utils; +use crate::ln::chan_utils::{ChannelTransactionParameters, HolderCommitmentTransaction}; +#[cfg(anchors)] +use crate::chain::chaininterface::ConfirmationTarget; +use crate::chain::chaininterface::{FeeEstimator, BroadcasterInterface, LowerBoundedFeeEstimator}; +use crate::chain::channelmonitor::{ANTI_REORG_DELAY, CLTV_SHARED_CLAIM_BUFFER}; +use crate::chain::keysinterface::{Sign, KeysInterface}; +#[cfg(anchors)] +use crate::chain::package::PackageSolvingData; +use crate::chain::package::PackageTemplate; +use crate::util::logger::Logger; +use crate::util::ser::{Readable, ReadableArgs, MaybeReadable, Writer, Writeable, VecWriter}; +use crate::util::byte_utils; + +use crate::io; +use crate::prelude::*; use alloc::collections::BTreeMap; use core::cmp; use core::ops::Deref; use core::mem::replace; +#[cfg(anchors)] +use core::mem::swap; use bitcoin::hashes::Hash; const MAX_ALLOC_SIZE: usize = 64*1024; @@ -162,11 +170,28 @@ impl Writeable for Option>> { } } +// Represents the different types of claims for which events are yielded externally to satisfy said +// claims. +#[cfg(anchors)] +pub(crate) enum ClaimEvent { + /// Event yielded to signal that the commitment transaction fee must be bumped to claim any + /// encumbered funds and proceed to HTLC resolution, if any HTLCs exist. + BumpCommitment { + package_target_feerate_sat_per_1000_weight: u32, + commitment_tx: Transaction, + anchor_output_idx: u32, + }, +} + /// Represents the different ways an output can be claimed (i.e., spent to an address under our /// control) onchain. pub(crate) enum OnchainClaim { /// A finalized transaction pending confirmation spending the output to claim. Tx(Transaction), + #[cfg(anchors)] + /// An event yielded externally to signal additional inputs must be added to a transaction + /// pending confirmation spending the output to claim. + Event(ClaimEvent), } /// OnchainTxHandler receives claiming requests, aggregates them if it's sound, broadcast and @@ -199,6 +224,8 @@ pub struct OnchainTxHandler { pub(crate) pending_claim_requests: HashMap, #[cfg(not(test))] pending_claim_requests: HashMap, + #[cfg(anchors)] + pending_claim_events: HashMap, // Used to link outpoints claimed in a connected block to a pending claim request. // Key is outpoint than monitor parsing has detected we have keys/scripts to claim @@ -348,6 +375,8 @@ impl<'a, K: KeysInterface> ReadableArgs<&'a K> for OnchainTxHandler { locktimed_packages, pending_claim_requests, onchain_events_awaiting_threshold_conf, + #[cfg(anchors)] + pending_claim_events: HashMap::new(), secp_ctx, }) } @@ -367,6 +396,8 @@ impl OnchainTxHandler { claimable_outpoints: HashMap::new(), locktimed_packages: BTreeMap::new(), onchain_events_awaiting_threshold_conf: Vec::new(), + #[cfg(anchors)] + pending_claim_events: HashMap::new(), secp_ctx, } @@ -380,10 +411,21 @@ impl OnchainTxHandler { self.holder_commitment.to_broadcaster_value_sat() } - /// Lightning security model (i.e being able to redeem/timeout HTLC or penalize coutnerparty onchain) lays on the assumption of claim transactions getting confirmed before timelock expiration - /// (CSV or CLTV following cases). In case of high-fee spikes, claim tx may stuck in the mempool, so you need to bump its feerate quickly using Replace-By-Fee or Child-Pay-For-Parent. - /// Panics if there are signing errors, because signing operations in reaction to on-chain events - /// are not expected to fail, and if they do, we may lose funds. + #[cfg(anchors)] + pub(crate) fn get_and_clear_pending_claim_events(&mut self) -> Vec { + let mut ret = HashMap::new(); + swap(&mut ret, &mut self.pending_claim_events); + ret.into_iter().map(|(_, event)| event).collect::>() + } + + /// Lightning security model (i.e being able to redeem/timeout HTLC or penalize counterparty + /// onchain) lays on the assumption of claim transactions getting confirmed before timelock + /// expiration (CSV or CLTV following cases). In case of high-fee spikes, claim tx may get stuck + /// in the mempool, so you need to bump its feerate quickly using Replace-By-Fee or + /// Child-Pay-For-Parent. + /// + /// Panics if there are signing errors, because signing operations in reaction to on-chain + /// events are not expected to fail, and if they do, we may lose funds. fn generate_claim(&mut self, cur_height: u32, cached_request: &PackageTemplate, fee_estimator: &LowerBoundedFeeEstimator, logger: &L) -> Option<(Option, u64, OnchainClaim)> where F::Target: FeeEstimator, L::Target: Logger, @@ -405,12 +447,60 @@ impl OnchainTxHandler { return Some((new_timer, new_feerate, OnchainClaim::Tx(transaction))) } } else { - // Note: Currently, amounts of holder outputs spending witnesses aren't used - // as we can't malleate spending package to increase their feerate. This - // should change with the remaining anchor output patchset. - if let Some(transaction) = cached_request.finalize_untractable_package(self, logger) { - return Some((None, 0, OnchainClaim::Tx(transaction))); + // Untractable packages cannot have their fees bumped through Replace-By-Fee. Some + // packages may support fee bumping through Child-Pays-For-Parent, indicated by those + // which require external funding. + #[cfg(not(anchors))] + let inputs = cached_request.inputs(); + #[cfg(anchors)] + let mut inputs = cached_request.inputs(); + debug_assert_eq!(inputs.len(), 1); + let tx = match cached_request.finalize_untractable_package(self, logger) { + Some(tx) => tx, + None => return None, + }; + if !cached_request.requires_external_funding() { + return Some((None, 0, OnchainClaim::Tx(tx))); } + #[cfg(anchors)] + return inputs.find_map(|input| match input { + // Commitment inputs with anchors support are the only untractable inputs supported + // thus far that require external funding. + PackageSolvingData::HolderFundingOutput(..) => { + debug_assert_eq!(tx.txid(), self.holder_commitment.trust().txid(), + "Holder commitment transaction mismatch"); + // We'll locate an anchor output we can spend within the commitment transaction. + let funding_pubkey = &self.channel_transaction_parameters.holder_pubkeys.funding_pubkey; + match chan_utils::get_anchor_output(&tx, funding_pubkey) { + // An anchor output was found, so we should yield a funding event externally. + Some((idx, _)) => { + // TODO: Use a lower confirmation target when both our and the + // counterparty's latest commitment don't have any HTLCs present. + let conf_target = ConfirmationTarget::HighPriority; + let package_target_feerate_sat_per_1000_weight = cached_request + .compute_package_feerate(fee_estimator, conf_target); + Some(( + new_timer, + package_target_feerate_sat_per_1000_weight as u64, + OnchainClaim::Event(ClaimEvent::BumpCommitment { + package_target_feerate_sat_per_1000_weight, + commitment_tx: tx.clone(), + anchor_output_idx: idx, + }), + )) + }, + // An anchor output was not found. There's nothing we can do other than + // attempt to broadcast the transaction with its current fee rate and hope + // it confirms. This is essentially the same behavior as a commitment + // transaction without anchor outputs. + None => Some((None, 0, OnchainClaim::Tx(tx.clone()))), + } + }, + _ => { + debug_assert!(false, "Only HolderFundingOutput inputs should be untractable and require external funding"); + None + }, + }); } None } @@ -490,6 +580,15 @@ impl OnchainTxHandler { broadcaster.broadcast_transaction(&tx); tx.txid() }, + #[cfg(anchors)] + OnchainClaim::Event(claim_event) => { + log_info!(logger, "Yielding onchain event to spend inputs {:?}", req.outpoints()); + let txid = match claim_event { + ClaimEvent::BumpCommitment { ref commitment_tx, .. } => commitment_tx.txid(), + }; + self.pending_claim_events.insert(txid, claim_event); + txid + }, }; for k in req.outpoints() { log_info!(logger, "Registering claiming request for {}:{}", k.txid, k.vout); @@ -587,6 +686,8 @@ impl OnchainTxHandler { for outpoint in request.outpoints() { log_debug!(logger, "Removing claim tracking for {} due to maturation of claim tx {}.", outpoint, claim_request); self.claimable_outpoints.remove(&outpoint); + #[cfg(anchors)] + self.pending_claim_events.remove(&claim_request); } } }, @@ -619,6 +720,11 @@ impl OnchainTxHandler { log_info!(logger, "Broadcasting RBF-bumped onchain {}", log_tx!(bump_tx)); broadcaster.broadcast_transaction(&bump_tx); }, + #[cfg(anchors)] + OnchainClaim::Event(claim_event) => { + log_info!(logger, "Yielding RBF-bumped onchain event to spend inputs {:?}", request.outpoints()); + self.pending_claim_events.insert(*first_claim_txid, claim_event); + }, } if let Some(request) = self.pending_claim_requests.get_mut(first_claim_txid) { request.set_timer(new_timer); @@ -681,7 +787,7 @@ impl OnchainTxHandler { self.onchain_events_awaiting_threshold_conf.push(entry); } } - for (_, request) in bump_candidates.iter_mut() { + for (_first_claim_txid_height, request) in bump_candidates.iter_mut() { if let Some((new_timer, new_feerate, bump_claim)) = self.generate_claim(height, &request, fee_estimator, &&*logger) { request.set_timer(new_timer); request.set_feerate(new_feerate); @@ -690,6 +796,11 @@ impl OnchainTxHandler { log_info!(logger, "Broadcasting onchain {}", log_tx!(bump_tx)); broadcaster.broadcast_transaction(&bump_tx); }, + #[cfg(anchors)] + OnchainClaim::Event(claim_event) => { + log_info!(logger, "Yielding onchain event after reorg to spend inputs {:?}", request.outpoints()); + self.pending_claim_events.insert(_first_claim_txid_height.0, claim_event); + }, } } }