//! OnchainTxHandler objects are fully-part of ChannelMonitor and encapsulates all
//! building, tracking, bumping and notifications functions.
+use bitcoin::PackedLockTime;
use bitcoin::blockdata::transaction::Transaction;
use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
use bitcoin::blockdata::script::Script;
-
+use bitcoin::hashes::{Hash, HashEngine};
+use bitcoin::hashes::sha256::Hash as Sha256;
use bitcoin::hash_types::{Txid, BlockHash};
-
use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature};
use bitcoin::secp256k1;
-use crate::chain::keysinterface::BaseSign;
+use crate::chain::chaininterface::compute_feerate_sat_per_1000_weight;
+use crate::sign::{ChannelSigner, EntropySource, SignerProvider};
use crate::ln::msgs::DecodeError;
use crate::ln::PaymentPreimage;
-#[cfg(anchors)]
-use crate::ln::chan_utils::{self, HTLCOutputInCommitment};
-use crate::ln::chan_utils::{ChannelTransactionParameters, HolderCommitmentTransaction};
-#[cfg(anchors)]
-use crate::chain::chaininterface::ConfirmationTarget;
-use crate::chain::chaininterface::{FeeEstimator, BroadcasterInterface, LowerBoundedFeeEstimator};
+use crate::ln::chan_utils::{self, ChannelTransactionParameters, HTLCOutputInCommitment, HolderCommitmentTransaction};
+use crate::chain::ClaimId;
+use crate::chain::chaininterface::{ConfirmationTarget, 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::sign::WriteableEcdsaChannelSigner;
+use crate::chain::package::{PackageSolvingData, PackageTemplate};
use crate::util::logger::Logger;
-use crate::util::ser::{Readable, ReadableArgs, MaybeReadable, Writer, Writeable, VecWriter};
+use crate::util::ser::{Readable, ReadableArgs, MaybeReadable, UpgradableRequired, Writer, Writeable, VecWriter};
use crate::io;
use crate::prelude::*;
use core::cmp;
use core::ops::Deref;
use core::mem::replace;
-#[cfg(anchors)]
use core::mem::swap;
-use bitcoin::hashes::Hash;
+use crate::ln::features::ChannelTypeFeatures;
const MAX_ALLOC_SIZE: usize = 64*1024;
/// transaction causing it.
///
/// Used to determine when the on-chain event can be considered safe from a chain reorganization.
-#[derive(PartialEq, Eq)]
+#[derive(Clone, PartialEq, Eq)]
struct OnchainEventEntry {
txid: Txid,
height: u32,
}
}
-/// 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(PartialEq, Eq)]
+/// Events for claims the [`OnchainTxHandler`] has generated. Once the events are considered safe
+/// from a chain reorg, the [`OnchainTxHandler`] will act accordingly.
+#[derive(Clone, PartialEq, Eq)]
enum OnchainEvent {
- /// Outpoint under claim process by our own tx, once this one get enough confirmations, we remove it from
- /// bump-txn candidate buffer.
+ /// A pending request has been claimed by a transaction spending the exact same set of outpoints
+ /// as the request. This claim can either be ours or from the counterparty. Once the claiming
+ /// transaction has met [`ANTI_REORG_DELAY`] confirmations, we consider it final and remove the
+ /// pending request.
Claim {
- package_id: PackageID,
+ claim_id: ClaimId,
},
- /// Claim tx aggregate multiple claimable outpoints. One of the outpoint may be claimed by a counterparty party tx.
- /// In this case, we need to drop the outpoint and regenerate a new claim tx. By safety, we keep tracking
- /// the outpoint to be sure to resurect it back to the claim tx if reorgs happen.
+ /// The counterparty has claimed an outpoint from one of our pending requests through a
+ /// different transaction than ours. If our transaction was attempting to claim multiple
+ /// outputs, we need to drop the outpoint claimed by the counterparty and regenerate a new claim
+ /// transaction for ourselves. We keep tracking, separately, the outpoint claimed by the
+ /// counterparty up to [`ANTI_REORG_DELAY`] confirmations to ensure we attempt to re-claim it
+ /// if the counterparty's claim is reorged from the chain.
ContentiousOutpoint {
package: PackageTemplate,
}
let mut txid = Txid::all_zeros();
let mut height = 0;
let mut block_hash = None;
- let mut event = None;
+ let mut event = UpgradableRequired(None);
read_tlv_fields!(reader, {
(0, txid, required),
(1, block_hash, option),
(2, height, required),
- (4, event, ignorable),
+ (4, event, upgradable_required),
});
- if let Some(ev) = event {
- Ok(Some(Self { txid, height, block_hash, event: ev }))
- } else {
- Ok(None)
- }
+ Ok(Some(Self { txid, height, block_hash, event: _init_tlv_based_struct_field!(event, upgradable_required) }))
}
}
impl_writeable_tlv_based_enum_upgradable!(OnchainEvent,
(0, Claim) => {
- (0, package_id, required),
+ (0, claim_id, required),
},
(1, ContentiousOutpoint) => {
(0, package, required),
}
}
-#[cfg(anchors)]
/// The claim commonly referred to as the pre-signed second-stage HTLC transaction.
+#[derive(Clone, PartialEq, Eq)]
pub(crate) struct ExternalHTLCClaim {
pub(crate) commitment_txid: Txid,
pub(crate) per_commitment_number: u64,
// Represents the different types of claims for which events are yielded externally to satisfy said
// claims.
-#[cfg(anchors)]
+#[derive(Clone, PartialEq, Eq)]
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.
BumpHTLC {
target_feerate_sat_per_1000_weight: u32,
htlcs: Vec<ExternalHTLCClaim>,
+ tx_lock_time: PackedLockTime,
},
}
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),
}
-/// An internal identifier to track pending package claims within the `OnchainTxHandler`.
-type PackageID = [u8; 32];
-
/// OnchainTxHandler receives claiming requests, aggregates them if it's sound, broadcast and
/// do RBF bumping if possible.
-pub struct OnchainTxHandler<ChannelSigner: Sign> {
+#[derive(Clone)]
+pub struct OnchainTxHandler<ChannelSigner: WriteableEcdsaChannelSigner> {
destination_script: Script,
holder_commitment: HolderCommitmentTransaction,
// holder_htlc_sigs and prev_holder_htlc_sigs are in the order as they appear in the commitment
// us and is immutable until all outpoint of the claimable set are post-anti-reorg-delay solved.
// Entry is cache of elements need to generate a bumped claiming transaction (see ClaimTxBumpMaterial)
#[cfg(test)] // Used in functional_test to verify sanitization
- pub(crate) pending_claim_requests: HashMap<PackageID, PackageTemplate>,
+ pub(crate) pending_claim_requests: HashMap<ClaimId, PackageTemplate>,
#[cfg(not(test))]
- pending_claim_requests: HashMap<PackageID, PackageTemplate>,
- #[cfg(anchors)]
- pending_claim_events: HashMap<PackageID, ClaimEvent>,
-
- // 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
- // Value is (pending claim request identifier, confirmation_block), identifier
- // is txid of the initial claiming transaction and is immutable until outpoint is
- // post-anti-reorg-delay solved, confirmaiton_block is used to erase entry if
- // block with output gets disconnected.
+ pending_claim_requests: HashMap<ClaimId, PackageTemplate>,
+
+ // Used to track external events that need to be forwarded to the `ChainMonitor`. This `Vec`
+ // essentially acts as an insertion-ordered `HashMap` – there should only ever be one occurrence
+ // of a `ClaimId`, which tracks its latest `ClaimEvent`, i.e., if a pending claim exists, and
+ // a new block has been connected, resulting in a new claim, the previous will be replaced with
+ // the new.
+ //
+ // These external events may be generated in the following cases:
+ // - A channel has been force closed by broadcasting the holder's latest commitment transaction
+ // - A block being connected/disconnected
+ // - Learning the preimage for an HTLC we can claim onchain
+ pending_claim_events: Vec<(ClaimId, ClaimEvent)>,
+
+ // Used to link outpoints claimed in a connected block to a pending claim request. The keys
+ // represent the outpoints that our `ChannelMonitor` has detected we have keys/scripts to
+ // claim. The values track the pending claim request identifier and the initial confirmation
+ // block height, and are immutable until the outpoint has enough confirmations to meet our
+ // [`ANTI_REORG_DELAY`]. The initial confirmation block height is used to remove the entry if
+ // the block gets disconnected.
#[cfg(test)] // Used in functional_test to verify sanitization
- pub claimable_outpoints: HashMap<BitcoinOutPoint, (PackageID, u32)>,
+ pub claimable_outpoints: HashMap<BitcoinOutPoint, (ClaimId, u32)>,
#[cfg(not(test))]
- claimable_outpoints: HashMap<BitcoinOutPoint, (PackageID, u32)>,
+ claimable_outpoints: HashMap<BitcoinOutPoint, (ClaimId, u32)>,
locktimed_packages: BTreeMap<u32, Vec<PackageTemplate>>,
pub(super) secp_ctx: Secp256k1<secp256k1::All>,
}
+impl<ChannelSigner: WriteableEcdsaChannelSigner> PartialEq for OnchainTxHandler<ChannelSigner> {
+ fn eq(&self, other: &Self) -> bool {
+ // `signer`, `secp_ctx`, and `pending_claim_events` are excluded on purpose.
+ self.destination_script == other.destination_script &&
+ self.holder_commitment == other.holder_commitment &&
+ self.holder_htlc_sigs == other.holder_htlc_sigs &&
+ self.prev_holder_commitment == other.prev_holder_commitment &&
+ self.prev_holder_htlc_sigs == other.prev_holder_htlc_sigs &&
+ self.channel_transaction_parameters == other.channel_transaction_parameters &&
+ self.pending_claim_requests == other.pending_claim_requests &&
+ self.claimable_outpoints == other.claimable_outpoints &&
+ self.locktimed_packages == other.locktimed_packages &&
+ self.onchain_events_awaiting_threshold_conf == other.onchain_events_awaiting_threshold_conf
+ }
+}
+
const SERIALIZATION_VERSION: u8 = 1;
const MIN_SERIALIZATION_VERSION: u8 = 1;
-impl<ChannelSigner: Sign> OnchainTxHandler<ChannelSigner> {
+impl<ChannelSigner: WriteableEcdsaChannelSigner> OnchainTxHandler<ChannelSigner> {
pub(crate) fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
}
}
-impl<'a, K: KeysInterface> ReadableArgs<(&'a K, u64, [u8; 32])> for OnchainTxHandler<K::Signer> {
- fn read<R: io::Read>(reader: &mut R, args: (&'a K, u64, [u8; 32])) -> Result<Self, DecodeError> {
- let keys_manager = args.0;
- let channel_value_satoshis = args.1;
- let channel_keys_id = args.2;
+impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP, u64, [u8; 32])> for OnchainTxHandler<SP::Signer> {
+ fn read<R: io::Read>(reader: &mut R, args: (&'a ES, &'b SP, u64, [u8; 32])) -> Result<Self, DecodeError> {
+ let entropy_source = args.0;
+ let signer_provider = args.1;
+ let channel_value_satoshis = args.2;
+ let channel_keys_id = args.3;
let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
bytes_read += bytes_to_read;
}
- let mut signer = keys_manager.derive_channel_signer(channel_value_satoshis, channel_keys_id);
+ let mut signer = signer_provider.derive_channel_signer(channel_value_satoshis, channel_keys_id);
signer.provide_channel_parameters(&channel_parameters);
let pending_claim_requests_len: u64 = Readable::read(reader)?;
read_tlv_fields!(reader, {});
let mut secp_ctx = Secp256k1::new();
- secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes());
+ secp_ctx.seeded_randomize(&entropy_source.get_secure_random_bytes());
Ok(OnchainTxHandler {
destination_script,
locktimed_packages,
pending_claim_requests,
onchain_events_awaiting_threshold_conf,
- #[cfg(anchors)]
- pending_claim_events: HashMap::new(),
+ pending_claim_events: Vec::new(),
secp_ctx,
})
}
}
-impl<ChannelSigner: Sign> OnchainTxHandler<ChannelSigner> {
+impl<ChannelSigner: WriteableEcdsaChannelSigner> OnchainTxHandler<ChannelSigner> {
pub(crate) fn new(destination_script: Script, signer: ChannelSigner, channel_parameters: ChannelTransactionParameters, holder_commitment: HolderCommitmentTransaction, secp_ctx: Secp256k1<secp256k1::All>) -> Self {
OnchainTxHandler {
destination_script,
claimable_outpoints: HashMap::new(),
locktimed_packages: BTreeMap::new(),
onchain_events_awaiting_threshold_conf: Vec::new(),
- #[cfg(anchors)]
- pending_claim_events: HashMap::new(),
-
+ pending_claim_events: Vec::new(),
secp_ctx,
}
}
self.holder_commitment.to_broadcaster_value_sat()
}
- #[cfg(anchors)]
- pub(crate) fn get_and_clear_pending_claim_events(&mut self) -> Vec<ClaimEvent> {
- let mut ret = HashMap::new();
- swap(&mut ret, &mut self.pending_claim_events);
- ret.into_iter().map(|(_, event)| event).collect::<Vec<_>>()
+ pub(crate) fn get_and_clear_pending_claim_events(&mut self) -> Vec<(ClaimId, ClaimEvent)> {
+ let mut events = Vec::new();
+ swap(&mut events, &mut self.pending_claim_events);
+ events
+ }
+
+ /// Triggers rebroadcasts/fee-bumps of pending claims from a force-closed channel. This is
+ /// crucial in preventing certain classes of pinning attacks, detecting substantial mempool
+ /// feerate changes between blocks, and ensuring reliability if broadcasting fails. We recommend
+ /// invoking this every 30 seconds, or lower if running in an environment with spotty
+ /// connections, like on mobile.
+ pub(crate) fn rebroadcast_pending_claims<B: Deref, F: Deref, L: Deref>(
+ &mut self, current_height: u32, broadcaster: &B, fee_estimator: &LowerBoundedFeeEstimator<F>,
+ logger: &L,
+ )
+ where
+ B::Target: BroadcasterInterface,
+ F::Target: FeeEstimator,
+ L::Target: Logger,
+ {
+ let mut bump_requests = Vec::with_capacity(self.pending_claim_requests.len());
+ for (claim_id, request) in self.pending_claim_requests.iter() {
+ let inputs = request.outpoints();
+ log_info!(logger, "Triggering rebroadcast/fee-bump for request with inputs {:?}", inputs);
+ bump_requests.push((*claim_id, request.clone()));
+ }
+ for (claim_id, request) in bump_requests {
+ self.generate_claim(current_height, &request, false /* force_feerate_bump */, fee_estimator, logger)
+ .map(|(_, new_feerate, claim)| {
+ let mut bumped_feerate = false;
+ if let Some(mut_request) = self.pending_claim_requests.get_mut(&claim_id) {
+ bumped_feerate = request.previous_feerate() > new_feerate;
+ mut_request.set_feerate(new_feerate);
+ }
+ match claim {
+ OnchainClaim::Tx(tx) => {
+ let log_start = if bumped_feerate { "Broadcasting RBF-bumped" } else { "Rebroadcasting" };
+ log_info!(logger, "{} onchain {}", log_start, log_tx!(tx));
+ broadcaster.broadcast_transactions(&[&tx]);
+ },
+ OnchainClaim::Event(event) => {
+ let log_start = if bumped_feerate { "Yielding fee-bumped" } else { "Replaying" };
+ log_info!(logger, "{} onchain event to spend inputs {:?}", log_start,
+ request.outpoints());
+ #[cfg(debug_assertions)] {
+ debug_assert!(request.requires_external_funding());
+ let num_existing = self.pending_claim_events.iter()
+ .filter(|entry| entry.0 == claim_id).count();
+ assert!(num_existing == 0 || num_existing == 1);
+ }
+ self.pending_claim_events.retain(|event| event.0 != claim_id);
+ self.pending_claim_events.push((claim_id, event));
+ }
+ }
+ });
+ }
}
/// Lightning security model (i.e being able to redeem/timeout HTLC or penalize counterparty
///
/// 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<F: Deref, L: Deref>(&mut self, cur_height: u32, cached_request: &PackageTemplate, fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L) -> Option<(Option<u32>, u64, OnchainClaim)>
- where F::Target: FeeEstimator,
- L::Target: Logger,
+ fn generate_claim<F: Deref, L: Deref>(
+ &mut self, cur_height: u32, cached_request: &PackageTemplate, force_feerate_bump: bool,
+ fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L,
+ ) -> Option<(u32, u64, OnchainClaim)>
+ where
+ F::Target: FeeEstimator,
+ L::Target: Logger,
{
let request_outpoints = cached_request.outpoints();
if request_outpoints.is_empty() {
// remove it once it reaches the confirmation threshold, or to generate a new claim if the
// transaction is reorged out.
let mut all_inputs_have_confirmed_spend = true;
- for outpoint in &request_outpoints {
- if let Some(first_claim_txid_height) = self.claimable_outpoints.get(outpoint) {
+ for outpoint in request_outpoints.iter() {
+ if let Some((request_claim_id, _)) = self.claimable_outpoints.get(*outpoint) {
// We check for outpoint spends within claims individually rather than as a set
// since requests can have outpoints split off.
if !self.onchain_events_awaiting_threshold_conf.iter()
- .any(|event_entry| if let OnchainEvent::Claim { package_id } = event_entry.event {
- first_claim_txid_height.0 == package_id
+ .any(|event_entry| if let OnchainEvent::Claim { claim_id } = event_entry.event {
+ *request_claim_id == claim_id
} else {
// The onchain event is not a claim, keep seeking until we find one.
false
// Compute new height timer to decide when we need to regenerate a new bumped version of the claim tx (if we
// didn't receive confirmation of it before, or not enough reorg-safe depth on top of it).
- let new_timer = Some(cached_request.get_height_timer(cur_height));
+ let new_timer = cached_request.get_height_timer(cur_height);
if cached_request.is_malleable() {
- #[cfg(anchors)]
- { // Attributes are not allowed on if expressions on our current MSRV of 1.41.
- if cached_request.requires_external_funding() {
- let target_feerate_sat_per_1000_weight = cached_request
- .compute_package_feerate(fee_estimator, ConfirmationTarget::HighPriority);
- if let Some(htlcs) = cached_request.construct_malleable_package_with_external_funding(self) {
- return Some((
- new_timer,
- target_feerate_sat_per_1000_weight as u64,
- OnchainClaim::Event(ClaimEvent::BumpHTLC {
- target_feerate_sat_per_1000_weight,
- htlcs,
- }),
- ));
- } else {
- return None;
- }
+ if cached_request.requires_external_funding() {
+ let target_feerate_sat_per_1000_weight = cached_request.compute_package_feerate(
+ fee_estimator, ConfirmationTarget::HighPriority, force_feerate_bump
+ );
+ if let Some(htlcs) = cached_request.construct_malleable_package_with_external_funding(self) {
+ return Some((
+ new_timer,
+ target_feerate_sat_per_1000_weight as u64,
+ OnchainClaim::Event(ClaimEvent::BumpHTLC {
+ target_feerate_sat_per_1000_weight,
+ htlcs,
+ tx_lock_time: PackedLockTime(cached_request.package_locktime(cur_height)),
+ }),
+ ));
+ } else {
+ return None;
}
}
let predicted_weight = cached_request.package_weight(&self.destination_script);
if let Some((output_value, new_feerate)) = cached_request.compute_package_output(
- predicted_weight, self.destination_script.dust_value().to_sat(), fee_estimator, logger,
+ predicted_weight, self.destination_script.dust_value().to_sat(),
+ force_feerate_bump, fee_estimator, logger,
) {
assert!(new_feerate != 0);
- let transaction = cached_request.finalize_malleable_package(self, output_value, self.destination_script.clone(), logger).unwrap();
- log_trace!(logger, "...with timer {} and feerate {}", new_timer.unwrap(), new_feerate);
+ let transaction = cached_request.finalize_malleable_package(
+ cur_height, self, output_value, self.destination_script.clone(), logger
+ ).unwrap();
+ log_trace!(logger, "...with timer {} and feerate {}", new_timer, new_feerate);
assert!(predicted_weight >= transaction.weight());
return Some((new_timer, new_feerate, 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) {
None => return None,
};
if !cached_request.requires_external_funding() {
- return Some((None, 0, OnchainClaim::Tx(tx)));
+ return Some((new_timer, 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(..) => {
+ PackageSolvingData::HolderFundingOutput(output) => {
debug_assert_eq!(tx.txid(), self.holder_commitment.trust().txid(),
"Holder commitment transaction mismatch");
+
+ let conf_target = ConfirmationTarget::HighPriority;
+ let package_target_feerate_sat_per_1000_weight = cached_request
+ .compute_package_feerate(fee_estimator, conf_target, force_feerate_bump);
+ if let Some(input_amount_sat) = output.funding_amount {
+ let fee_sat = input_amount_sat - tx.output.iter().map(|output| output.value).sum::<u64>();
+ let commitment_tx_feerate_sat_per_1000_weight =
+ compute_feerate_sat_per_1000_weight(fee_sat, tx.weight() as u64);
+ if commitment_tx_feerate_sat_per_1000_weight >= package_target_feerate_sat_per_1000_weight {
+ log_debug!(logger, "Pre-signed {} already has feerate {} sat/kW above required {} sat/kW",
+ log_tx!(tx), commitment_tx_feerate_sat_per_1000_weight,
+ package_target_feerate_sat_per_1000_weight);
+ return Some((new_timer, 0, OnchainClaim::Tx(tx.clone())));
+ }
+ }
+
// 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) {
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,
// 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()))),
+ None => Some((new_timer, 0, OnchainClaim::Tx(tx.clone()))),
}
},
_ => {
.find(|locked_package| locked_package.outpoints() == req.outpoints());
if let Some(package) = timelocked_equivalent_package {
log_info!(logger, "Ignoring second claim for outpoint {}:{}, we already have one which we're waiting on a timelock at {} for.",
- req.outpoints()[0].txid, req.outpoints()[0].vout, package.package_timelock());
+ req.outpoints()[0].txid, req.outpoints()[0].vout, package.package_locktime(cur_height));
continue;
}
- if req.package_timelock() > cur_height + 1 {
- log_info!(logger, "Delaying claim of package until its timelock at {} (current height {}), the following outpoints are spent:", req.package_timelock(), cur_height);
+ let package_locktime = req.package_locktime(cur_height);
+ if package_locktime > cur_height + 1 {
+ log_info!(logger, "Delaying claim of package until its timelock at {} (current height {}), the following outpoints are spent:", package_locktime, cur_height);
for outpoint in req.outpoints() {
log_info!(logger, " Outpoint {}", outpoint);
}
- self.locktimed_packages.entry(req.package_timelock()).or_insert(Vec::new()).push(req);
+ self.locktimed_packages.entry(package_locktime).or_insert(Vec::new()).push(req);
continue;
}
preprocessed_requests.push(req);
}
- // Claim everything up to and including cur_height + 1
- let remaining_locked_packages = self.locktimed_packages.split_off(&(cur_height + 2));
+ // Claim everything up to and including `cur_height`
+ let remaining_locked_packages = self.locktimed_packages.split_off(&(cur_height + 1));
for (pop_height, mut entry) in self.locktimed_packages.iter_mut() {
log_trace!(logger, "Restoring delayed claim of package(s) at their timelock at {}.", pop_height);
preprocessed_requests.append(&mut entry);
// Generate claim transactions and track them to bump if necessary at
// height timer expiration (i.e in how many blocks we're going to take action).
for mut req in preprocessed_requests {
- if let Some((new_timer, new_feerate, claim)) = self.generate_claim(cur_height, &req, &*fee_estimator, &*logger) {
+ if let Some((new_timer, new_feerate, claim)) = self.generate_claim(
+ cur_height, &req, true /* force_feerate_bump */, &*fee_estimator, &*logger,
+ ) {
req.set_timer(new_timer);
req.set_feerate(new_feerate);
- let package_id = match claim {
+ // Once a pending claim has an id assigned, it remains fixed until the claim is
+ // satisfied, regardless of whether the claim switches between different variants of
+ // `OnchainClaim`.
+ let claim_id = match claim {
OnchainClaim::Tx(tx) => {
log_info!(logger, "Broadcasting onchain {}", log_tx!(tx));
- broadcaster.broadcast_transaction(&tx);
- tx.txid().into_inner()
+ broadcaster.broadcast_transactions(&[&tx]);
+ ClaimId(tx.txid().into_inner())
},
- #[cfg(anchors)]
OnchainClaim::Event(claim_event) => {
log_info!(logger, "Yielding onchain event to spend inputs {:?}", req.outpoints());
- let package_id = match claim_event {
- ClaimEvent::BumpCommitment { ref commitment_tx, .. } => commitment_tx.txid().into_inner(),
+ let claim_id = match claim_event {
+ ClaimEvent::BumpCommitment { ref commitment_tx, .. } =>
+ // For commitment claims, we can just use their txid as it should
+ // already be unique.
+ ClaimId(commitment_tx.txid().into_inner()),
ClaimEvent::BumpHTLC { ref htlcs, .. } => {
- // Use the same construction as a lightning channel id to generate
- // the package id for this request based on the first HTLC. It
- // doesn't matter what we use as long as it's unique per request.
- let mut package_id = [0; 32];
- package_id[..].copy_from_slice(&htlcs[0].commitment_txid[..]);
- let htlc_output_index = htlcs[0].htlc.transaction_output_index.unwrap();
- package_id[30] ^= ((htlc_output_index >> 8) & 0xff) as u8;
- package_id[31] ^= ((htlc_output_index >> 0) & 0xff) as u8;
- package_id
+ // For HTLC claims, commit to the entire set of HTLC outputs to
+ // claim, which will always be unique per request. Once a claim ID
+ // is generated, it is assigned and remains unchanged, even if the
+ // underlying set of HTLCs changes.
+ let mut engine = Sha256::engine();
+ for htlc in htlcs {
+ engine.input(&htlc.commitment_txid.into_inner());
+ engine.input(&htlc.htlc.transaction_output_index.unwrap().to_be_bytes());
+ }
+ ClaimId(Sha256::from_engine(engine).into_inner())
},
};
- self.pending_claim_events.insert(package_id, claim_event);
- package_id
+ debug_assert!(self.pending_claim_requests.get(&claim_id).is_none());
+ debug_assert_eq!(self.pending_claim_events.iter().filter(|entry| entry.0 == claim_id).count(), 0);
+ self.pending_claim_events.push((claim_id, claim_event));
+ claim_id
},
};
+ debug_assert!(self.pending_claim_requests.get(&claim_id).is_none());
for k in req.outpoints() {
log_info!(logger, "Registering claiming request for {}:{}", k.txid, k.vout);
- self.claimable_outpoints.insert(k.clone(), (package_id, conf_height));
+ self.claimable_outpoints.insert(k.clone(), (claim_id, conf_height));
}
- self.pending_claim_requests.insert(package_id, req);
+ self.pending_claim_requests.insert(claim_id, req);
}
}
}
// Scan all input to verify is one of the outpoint spent is of interest for us
let mut claimed_outputs_material = Vec::new();
for inp in &tx.input {
- if let Some(first_claim_txid_height) = self.claimable_outpoints.get(&inp.previous_output) {
+ if let Some((claim_id, _)) = self.claimable_outpoints.get(&inp.previous_output) {
// If outpoint has claim request pending on it...
- if let Some(request) = self.pending_claim_requests.get_mut(&first_claim_txid_height.0) {
+ if let Some(request) = self.pending_claim_requests.get_mut(claim_id) {
//... we need to verify equality between transaction outpoints and claim request
// outpoints to know if transaction is the original claim or a bumped one issued
// by us.
txid: tx.txid(),
height: conf_height,
block_hash: Some(conf_hash),
- event: OnchainEvent::Claim { package_id: first_claim_txid_height.0 }
+ event: OnchainEvent::Claim { claim_id: *claim_id }
};
if !self.onchain_events_awaiting_threshold_conf.contains(&entry) {
self.onchain_events_awaiting_threshold_conf.push(entry);
}
//TODO: recompute soonest_timelock to avoid wasting a bit on fees
if at_least_one_drop {
- bump_candidates.insert(first_claim_txid_height.0.clone(), request.clone());
+ bump_candidates.insert(*claim_id, request.clone());
+ // If we have any pending claim events for the request being updated
+ // that have yet to be consumed, we'll remove them since they will
+ // end up producing an invalid transaction by double spending
+ // input(s) that already have a confirmed spend. If such spend is
+ // reorged out of the chain, then we'll attempt to re-spend the
+ // inputs once we see it.
+ #[cfg(debug_assertions)] {
+ let existing = self.pending_claim_events.iter()
+ .filter(|entry| entry.0 == *claim_id).count();
+ assert!(existing == 0 || existing == 1);
+ }
+ self.pending_claim_events.retain(|entry| entry.0 != *claim_id);
}
}
break; //No need to iterate further, either tx is our or their
for entry in onchain_events_awaiting_threshold_conf {
if entry.has_reached_confirmation_threshold(cur_height) {
match entry.event {
- OnchainEvent::Claim { package_id } => {
+ OnchainEvent::Claim { claim_id } => {
// We may remove a whole set of claim outpoints here, as these one may have
// been aggregated in a single tx and claimed so atomically
- if let Some(request) = self.pending_claim_requests.remove(&package_id) {
+ if let Some(request) = self.pending_claim_requests.remove(&claim_id) {
for outpoint in request.outpoints() {
log_debug!(logger, "Removing claim tracking for {} due to maturation of claim package {}.",
- outpoint, log_bytes!(package_id));
- self.claimable_outpoints.remove(&outpoint);
- #[cfg(anchors)]
- self.pending_claim_events.remove(&package_id);
+ outpoint, log_bytes!(claim_id.0));
+ self.claimable_outpoints.remove(outpoint);
+ }
+ #[cfg(debug_assertions)] {
+ let num_existing = self.pending_claim_events.iter()
+ .filter(|entry| entry.0 == claim_id).count();
+ assert!(num_existing == 0 || num_existing == 1);
}
+ self.pending_claim_events.retain(|(id, _)| *id != claim_id);
}
},
OnchainEvent::ContentiousOutpoint { package } => {
log_debug!(logger, "Removing claim tracking due to maturation of claim tx for outpoints:");
log_debug!(logger, " {:?}", package.outpoints());
- self.claimable_outpoints.remove(&package.outpoints()[0]);
+ self.claimable_outpoints.remove(package.outpoints()[0]);
}
}
} else {
}
// Check if any pending claim request must be rescheduled
- for (first_claim_txid, ref request) in self.pending_claim_requests.iter() {
- if let Some(h) = request.timer() {
- if cur_height >= h {
- bump_candidates.insert(*first_claim_txid, (*request).clone());
- }
+ for (claim_id, request) in self.pending_claim_requests.iter() {
+ if cur_height >= request.timer() {
+ bump_candidates.insert(*claim_id, request.clone());
}
}
// Build, bump and rebroadcast tx accordingly
log_trace!(logger, "Bumping {} candidates", bump_candidates.len());
- for (first_claim_txid, request) in bump_candidates.iter() {
- if let Some((new_timer, new_feerate, bump_claim)) = self.generate_claim(cur_height, &request, &*fee_estimator, &*logger) {
+ for (claim_id, request) in bump_candidates.iter() {
+ if let Some((new_timer, new_feerate, bump_claim)) = self.generate_claim(
+ cur_height, &request, true /* force_feerate_bump */, &*fee_estimator, &*logger,
+ ) {
match bump_claim {
OnchainClaim::Tx(bump_tx) => {
log_info!(logger, "Broadcasting RBF-bumped onchain {}", log_tx!(bump_tx));
- broadcaster.broadcast_transaction(&bump_tx);
+ broadcaster.broadcast_transactions(&[&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);
+ #[cfg(debug_assertions)] {
+ let num_existing = self.pending_claim_events.iter().
+ filter(|entry| entry.0 == *claim_id).count();
+ assert!(num_existing == 0 || num_existing == 1);
+ }
+ self.pending_claim_events.retain(|event| event.0 != *claim_id);
+ self.pending_claim_events.push((*claim_id, claim_event));
},
}
- if let Some(request) = self.pending_claim_requests.get_mut(first_claim_txid) {
+ if let Some(request) = self.pending_claim_requests.get_mut(claim_id) {
request.set_timer(new_timer);
request.set_feerate(new_feerate);
}
//- resurect outpoint back in its claimable set and regenerate tx
match entry.event {
OnchainEvent::ContentiousOutpoint { package } => {
- if let Some(ancestor_claimable_txid) = self.claimable_outpoints.get(&package.outpoints()[0]) {
- if let Some(request) = self.pending_claim_requests.get_mut(&ancestor_claimable_txid.0) {
+ if let Some(pending_claim) = self.claimable_outpoints.get(package.outpoints()[0]) {
+ if let Some(request) = self.pending_claim_requests.get_mut(&pending_claim.0) {
request.merge_package(package);
// Using a HashMap guarantee us than if we have multiple outpoints getting
// resurrected only one bump claim tx is going to be broadcast
- bump_candidates.insert(ancestor_claimable_txid.clone(), request.clone());
+ bump_candidates.insert(pending_claim.clone(), request.clone());
}
}
},
self.onchain_events_awaiting_threshold_conf.push(entry);
}
}
- 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) {
+ for ((_claim_id, _), ref mut request) in bump_candidates.iter_mut() {
+ // `height` is the height being disconnected, so our `current_height` is 1 lower.
+ let current_height = height - 1;
+ if let Some((new_timer, new_feerate, bump_claim)) = self.generate_claim(
+ current_height, &request, true /* force_feerate_bump */, fee_estimator, &&*logger
+ ) {
request.set_timer(new_timer);
request.set_feerate(new_feerate);
match bump_claim {
OnchainClaim::Tx(bump_tx) => {
log_info!(logger, "Broadcasting onchain {}", log_tx!(bump_tx));
- broadcaster.broadcast_transaction(&bump_tx);
+ broadcaster.broadcast_transactions(&[&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);
+ #[cfg(debug_assertions)] {
+ let num_existing = self.pending_claim_events.iter()
+ .filter(|entry| entry.0 == *_claim_id).count();
+ assert!(num_existing == 0 || num_existing == 1);
+ }
+ self.pending_claim_events.retain(|event| event.0 != *_claim_id);
+ self.pending_claim_events.push((*_claim_id, claim_event));
},
}
}
ret
}
+ pub(crate) fn get_unsigned_holder_commitment_tx(&self) -> &Transaction {
+ &self.holder_commitment.trust().built_transaction().transaction
+ }
+
//TODO: getting lastest holder transactions should be infallible and result in us "force-closing the channel", but we may
- // have empty holder commitment transaction if a ChannelMonitor is asked to force-close just after Channel::get_outbound_funding_created,
+ // have empty holder commitment transaction if a ChannelMonitor is asked to force-close just after OutboundV1Channel::get_funding_created,
// before providing a initial commitment transaction. For outbound channel, init ChannelMonitor at Channel::funding_signed, there is nothing
// to monitor before.
pub(crate) fn get_fully_signed_holder_tx(&mut self, funding_redeemscript: &Script) -> Transaction {
htlc_tx
}
- #[cfg(anchors)]
pub(crate) fn generate_external_htlc_claim(
- &mut self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>
+ &self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>
) -> Option<ExternalHTLCClaim> {
let find_htlc = |holder_commitment: &HolderCommitmentTransaction| -> Option<ExternalHTLCClaim> {
let trusted_tx = holder_commitment.trust();
.or_else(|| self.prev_holder_commitment.as_ref().map(|c| find_htlc(c)).flatten())
}
- pub(crate) fn opt_anchors(&self) -> bool {
- self.channel_transaction_parameters.opt_anchors.is_some()
+ pub(crate) fn channel_type_features(&self) -> &ChannelTypeFeatures {
+ &self.channel_transaction_parameters.channel_type_features
}
#[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]