//! OnchainTxHandler objects are fully-part of ChannelMonitor and encapsulates all
//! building, tracking, bumping and notifications functions.
-#[cfg(anchors)]
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::{ChannelSigner, EntropySource, SignerProvider};
+use crate::chain::chaininterface::compute_feerate_sat_per_1000_weight;
+use crate::sign::{ChannelDerivationParameters, HTLCDescriptor, ChannelSigner, EntropySource, SignerProvider, WriteableEcdsaChannelSigner};
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::WriteableEcdsaChannelSigner;
-#[cfg(anchors)]
-use crate::chain::package::PackageSolvingData;
-use crate::chain::package::PackageTemplate;
+use crate::chain::package::{PackageSolvingData, PackageTemplate};
use crate::util::logger::Logger;
use crate::util::ser::{Readable, ReadableArgs, MaybeReadable, UpgradableRequired, Writer, Writeable, VecWriter};
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,
/// Events for claims the [`OnchainTxHandler`] has generated. Once the events are considered safe
/// from a chain reorg, the [`OnchainTxHandler`] will act accordingly.
-#[derive(PartialEq, Eq)]
+#[derive(Clone, PartialEq, Eq)]
enum OnchainEvent {
/// 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,
},
/// 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
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.
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.
+#[derive(Clone)]
pub struct OnchainTxHandler<ChannelSigner: WriteableEcdsaChannelSigner> {
+ channel_value_satoshis: u64,
+ channel_keys_id: [u8; 32],
destination_script: Script,
holder_commitment: HolderCommitmentTransaction,
- // holder_htlc_sigs and prev_holder_htlc_sigs are in the order as they appear in the commitment
- // transaction outputs (hence the Option<>s inside the Vec). The first usize is the index in
- // the set of HTLCs in the HolderCommitmentTransaction.
- holder_htlc_sigs: Option<Vec<Option<(usize, Signature)>>>,
prev_holder_commitment: Option<HolderCommitmentTransaction>,
- prev_holder_htlc_sigs: Option<Vec<Option<(usize, Signature)>>>,
pub(super) signer: ChannelSigner,
pub(crate) channel_transaction_parameters: ChannelTransactionParameters,
// 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>,
+ 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 `PackageID`, which tracks its latest `ClaimEvent`, i.e., if a pending claim exists, and
+ // 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.
//
// - 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
- #[cfg(anchors)]
- pending_claim_events: Vec<(PackageID, ClaimEvent)>,
+ 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
// [`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>>,
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.channel_value_satoshis == other.channel_value_satoshis &&
+ self.channel_keys_id == other.channel_keys_id &&
+ 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.destination_script.write(writer)?;
self.holder_commitment.write(writer)?;
- self.holder_htlc_sigs.write(writer)?;
+ None::<Option<Vec<Option<(usize, Signature)>>>>.write(writer)?; // holder_htlc_sigs
self.prev_holder_commitment.write(writer)?;
- self.prev_holder_htlc_sigs.write(writer)?;
+ None::<Option<Vec<Option<(usize, Signature)>>>>.write(writer)?; // prev_holder_htlc_sigs
self.channel_transaction_parameters.write(writer)?;
let destination_script = Readable::read(reader)?;
let holder_commitment = Readable::read(reader)?;
- let holder_htlc_sigs = Readable::read(reader)?;
+ let _holder_htlc_sigs: Option<Vec<Option<(usize, Signature)>>> = Readable::read(reader)?;
let prev_holder_commitment = Readable::read(reader)?;
- let prev_holder_htlc_sigs = Readable::read(reader)?;
+ let _prev_holder_htlc_sigs: Option<Vec<Option<(usize, Signature)>>> = Readable::read(reader)?;
let channel_parameters = Readable::read(reader)?;
secp_ctx.seeded_randomize(&entropy_source.get_secure_random_bytes());
Ok(OnchainTxHandler {
+ channel_value_satoshis,
+ channel_keys_id,
destination_script,
holder_commitment,
- holder_htlc_sigs,
prev_holder_commitment,
- prev_holder_htlc_sigs,
signer,
channel_transaction_parameters: channel_parameters,
claimable_outpoints,
locktimed_packages,
pending_claim_requests,
onchain_events_awaiting_threshold_conf,
- #[cfg(anchors)]
pending_claim_events: Vec::new(),
secp_ctx,
})
}
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 {
+ pub(crate) fn new(
+ channel_value_satoshis: u64, channel_keys_id: [u8; 32], destination_script: Script,
+ signer: ChannelSigner, channel_parameters: ChannelTransactionParameters,
+ holder_commitment: HolderCommitmentTransaction, secp_ctx: Secp256k1<secp256k1::All>
+ ) -> Self {
OnchainTxHandler {
+ channel_value_satoshis,
+ channel_keys_id,
destination_script,
holder_commitment,
- holder_htlc_sigs: None,
prev_holder_commitment: None,
- prev_holder_htlc_sigs: None,
signer,
channel_transaction_parameters: channel_parameters,
pending_claim_requests: HashMap::new(),
claimable_outpoints: HashMap::new(),
locktimed_packages: BTreeMap::new(),
onchain_events_awaiting_threshold_conf: Vec::new(),
- #[cfg(anchors)]
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> {
+ 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.into_iter().map(|(_, event)| event).collect()
+ 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() {
// transaction is reorged out.
let mut all_inputs_have_confirmed_spend = true;
for outpoint in request_outpoints.iter() {
- if let Some((request_package_id, _)) = self.claimable_outpoints.get(*outpoint) {
+ 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 {
- *request_package_id == 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,
- tx_lock_time: PackedLockTime(cached_request.package_locktime(cur_height)),
- }),
- ));
- } else {
- return None;
- }
+ if cached_request.requires_external_funding() {
+ let target_feerate_sat_per_1000_weight = cached_request.compute_package_feerate(
+ fee_estimator, ConfirmationTarget::OnChainSweep, 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(
cur_height, self, output_value, self.destination_script.clone(), logger
).unwrap();
- log_trace!(logger, "...with timer {} and feerate {}", new_timer.unwrap(), new_feerate);
+ 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) {
if !cached_request.requires_external_funding() {
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::OnChainSweep;
+ 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()))),
}
},
_ => {
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())
},
};
- debug_assert_eq!(self.pending_claim_events.iter().filter(|entry| entry.0 == package_id).count(), 0);
- self.pending_claim_events.push((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((package_id, _)) = 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(package_id) {
+ 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: *package_id }
+ 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(*package_id, 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(anchors)] {
- #[cfg(debug_assertions)] {
- let existing = self.pending_claim_events.iter()
- .filter(|entry| entry.0 == *package_id).count();
- assert!(existing == 0 || existing == 1);
- }
- self.pending_claim_events.retain(|entry| entry.0 != *package_id);
+ #[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));
+ outpoint, log_bytes!(claim_id.0));
self.claimable_outpoints.remove(outpoint);
}
- #[cfg(anchors)] {
- #[cfg(debug_assertions)] {
- let num_existing = self.pending_claim_events.iter()
- .filter(|entry| entry.0 == package_id).count();
- assert!(num_existing == 0 || num_existing == 1);
- }
- self.pending_claim_events.retain(|(id, _)| *id != package_id);
+ #[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 } => {
}
// Check if any pending claim request must be rescheduled
- for (package_id, request) in self.pending_claim_requests.iter() {
- if let Some(h) = request.timer() {
- if cur_height >= h {
- bump_candidates.insert(*package_id, 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 (package_id, 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());
#[cfg(debug_assertions)] {
let num_existing = self.pending_claim_events.iter().
- filter(|entry| entry.0 == *package_id).count();
+ filter(|entry| entry.0 == *claim_id).count();
assert!(num_existing == 0 || num_existing == 1);
}
- self.pending_claim_events.retain(|event| event.0 != *package_id);
- self.pending_claim_events.push((*package_id, claim_event));
+ 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(package_id) {
+ if let Some(request) = self.pending_claim_requests.get_mut(claim_id) {
request.set_timer(new_timer);
request.set_feerate(new_feerate);
}
self.onchain_events_awaiting_threshold_conf.push(entry);
}
}
- for ((_package_id, _), ref mut 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());
#[cfg(debug_assertions)] {
let num_existing = self.pending_claim_events.iter()
- .filter(|entry| entry.0 == *_package_id).count();
+ .filter(|entry| entry.0 == *_claim_id).count();
assert!(num_existing == 0 || num_existing == 1);
}
- self.pending_claim_events.retain(|event| event.0 != *_package_id);
- self.pending_claim_events.push((*_package_id, claim_event));
+ self.pending_claim_events.retain(|event| event.0 != *_claim_id);
+ self.pending_claim_events.push((*_claim_id, claim_event));
},
}
}
pub(crate) fn provide_latest_holder_tx(&mut self, tx: HolderCommitmentTransaction) {
self.prev_holder_commitment = Some(replace(&mut self.holder_commitment, tx));
- self.holder_htlc_sigs = None;
- }
-
- // Normally holder HTLCs are signed at the same time as the holder commitment tx. However,
- // in some configurations, the holder commitment tx has been signed and broadcast by a
- // ChannelMonitor replica, so we handle that case here.
- fn sign_latest_holder_htlcs(&mut self) {
- if self.holder_htlc_sigs.is_none() {
- let (_sig, sigs) = self.signer.sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("sign holder commitment");
- self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, sigs));
- }
}
- // Normally only the latest commitment tx and HTLCs need to be signed. However, in some
- // configurations we may have updated our holder commitment but a replica of the ChannelMonitor
- // broadcast the previous one before we sync with it. We handle that case here.
- fn sign_prev_holder_htlcs(&mut self) {
- if self.prev_holder_htlc_sigs.is_none() {
- if let Some(ref holder_commitment) = self.prev_holder_commitment {
- let (_sig, sigs) = self.signer.sign_holder_commitment_and_htlcs(holder_commitment, &self.secp_ctx).expect("sign previous holder commitment");
- self.prev_holder_htlc_sigs = Some(Self::extract_holder_sigs(holder_commitment, sigs));
- }
- }
- }
-
- fn extract_holder_sigs(holder_commitment: &HolderCommitmentTransaction, sigs: Vec<Signature>) -> Vec<Option<(usize, Signature)>> {
- let mut ret = Vec::new();
- for (htlc_idx, (holder_sig, htlc)) in sigs.iter().zip(holder_commitment.htlcs().iter()).enumerate() {
- let tx_idx = htlc.transaction_output_index.unwrap();
- if ret.len() <= tx_idx as usize { ret.resize(tx_idx as usize + 1, None); }
- ret[tx_idx as usize] = Some((htlc_idx, holder_sig.clone()));
- }
- 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 {
- let (sig, htlc_sigs) = self.signer.sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("signing holder commitment");
- self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, htlc_sigs));
+ let sig = self.signer.sign_holder_commitment(&self.holder_commitment, &self.secp_ctx).expect("signing holder commitment");
self.holder_commitment.add_holder_sig(funding_redeemscript, sig)
}
#[cfg(any(test, feature="unsafe_revoked_tx_signing"))]
pub(crate) fn get_fully_signed_copy_holder_tx(&mut self, funding_redeemscript: &Script) -> Transaction {
- let (sig, htlc_sigs) = self.signer.unsafe_sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("sign holder commitment");
- self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, htlc_sigs));
+ let sig = self.signer.unsafe_sign_holder_commitment(&self.holder_commitment, &self.secp_ctx).expect("sign holder commitment");
self.holder_commitment.add_holder_sig(funding_redeemscript, sig)
}
pub(crate) fn get_fully_signed_htlc_tx(&mut self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>) -> Option<Transaction> {
- let mut htlc_tx = None;
- let commitment_txid = self.holder_commitment.trust().txid();
- // Check if the HTLC spends from the current holder commitment
- if commitment_txid == outp.txid {
- self.sign_latest_holder_htlcs();
- if let &Some(ref htlc_sigs) = &self.holder_htlc_sigs {
- let &(ref htlc_idx, ref htlc_sig) = htlc_sigs[outp.vout as usize].as_ref().unwrap();
- let trusted_tx = self.holder_commitment.trust();
- let counterparty_htlc_sig = self.holder_commitment.counterparty_htlc_sigs[*htlc_idx];
- htlc_tx = Some(trusted_tx
- .get_signed_htlc_tx(&self.channel_transaction_parameters.as_holder_broadcastable(), *htlc_idx, &counterparty_htlc_sig, htlc_sig, preimage));
- }
- }
- // If the HTLC doesn't spend the current holder commitment, check if it spends the previous one
- if htlc_tx.is_none() && self.prev_holder_commitment.is_some() {
- let commitment_txid = self.prev_holder_commitment.as_ref().unwrap().trust().txid();
- if commitment_txid == outp.txid {
- self.sign_prev_holder_htlcs();
- if let &Some(ref htlc_sigs) = &self.prev_holder_htlc_sigs {
- let &(ref htlc_idx, ref htlc_sig) = htlc_sigs[outp.vout as usize].as_ref().unwrap();
- let holder_commitment = self.prev_holder_commitment.as_ref().unwrap();
- let trusted_tx = holder_commitment.trust();
- let counterparty_htlc_sig = holder_commitment.counterparty_htlc_sigs[*htlc_idx];
- htlc_tx = Some(trusted_tx
- .get_signed_htlc_tx(&self.channel_transaction_parameters.as_holder_broadcastable(), *htlc_idx, &counterparty_htlc_sig, htlc_sig, preimage));
- }
+ let get_signed_htlc_tx = |holder_commitment: &HolderCommitmentTransaction| {
+ let trusted_tx = holder_commitment.trust();
+ if trusted_tx.txid() != outp.txid {
+ return None;
}
- }
- htlc_tx
+ let (htlc_idx, htlc) = trusted_tx.htlcs().iter().enumerate()
+ .find(|(_, htlc)| htlc.transaction_output_index.unwrap() == outp.vout)
+ .unwrap();
+ let counterparty_htlc_sig = holder_commitment.counterparty_htlc_sigs[htlc_idx];
+ let mut htlc_tx = trusted_tx.build_unsigned_htlc_tx(
+ &self.channel_transaction_parameters.as_holder_broadcastable(), htlc_idx, preimage,
+ );
+
+ let htlc_descriptor = HTLCDescriptor {
+ channel_derivation_parameters: ChannelDerivationParameters {
+ value_satoshis: self.channel_value_satoshis,
+ keys_id: self.channel_keys_id,
+ transaction_parameters: self.channel_transaction_parameters.clone(),
+ },
+ commitment_txid: trusted_tx.txid(),
+ per_commitment_number: trusted_tx.commitment_number(),
+ per_commitment_point: trusted_tx.per_commitment_point(),
+ feerate_per_kw: trusted_tx.feerate_per_kw(),
+ htlc: htlc.clone(),
+ preimage: preimage.clone(),
+ counterparty_sig: counterparty_htlc_sig.clone(),
+ };
+ let htlc_sig = self.signer.sign_holder_htlc_transaction(&htlc_tx, 0, &htlc_descriptor, &self.secp_ctx).unwrap();
+ htlc_tx.input[0].witness = trusted_tx.build_htlc_input_witness(
+ htlc_idx, &counterparty_htlc_sig, &htlc_sig, preimage,
+ );
+ Some(htlc_tx)
+ };
+
+ // Check if the HTLC spends from the current holder commitment first, or the previous.
+ get_signed_htlc_tx(&self.holder_commitment)
+ .or_else(|| self.prev_holder_commitment.as_ref().and_then(|prev_holder_commitment| get_signed_htlc_tx(prev_holder_commitment)))
}
- #[cfg(anchors)]
pub(crate) fn generate_external_htlc_claim(
&self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>
) -> Option<ExternalHTLCClaim> {
.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()
- }
-
- #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
- pub(crate) fn unsafe_get_fully_signed_htlc_tx(&mut self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>) -> Option<Transaction> {
- let latest_had_sigs = self.holder_htlc_sigs.is_some();
- let prev_had_sigs = self.prev_holder_htlc_sigs.is_some();
- let ret = self.get_fully_signed_htlc_tx(outp, preimage);
- if !latest_had_sigs {
- self.holder_htlc_sigs = None;
- }
- if !prev_had_sigs {
- self.prev_holder_htlc_sigs = None;
- }
- ret
+ pub(crate) fn channel_type_features(&self) -> &ChannelTypeFeatures {
+ &self.channel_transaction_parameters.channel_type_features
}
}
projects / rust-lightning / blobdiff