1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! Various utilities to assemble claimable outpoints in package of one or more transactions. Those
11 //! packages are attached metadata, guiding their aggregable or fee-bumping re-schedule. This file
12 //! also includes witness weight computation and fee computation methods.
14 use bitcoin::blockdata::constants::WITNESS_SCALE_FACTOR;
15 use bitcoin::blockdata::transaction::{TxOut,TxIn, Transaction, EcdsaSighashType};
16 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
17 use bitcoin::blockdata::script::Script;
19 use bitcoin::hash_types::Txid;
21 use bitcoin::secp256k1::{SecretKey,PublicKey};
23 use crate::ln::PaymentPreimage;
24 use crate::ln::chan_utils::{TxCreationKeys, HTLCOutputInCommitment};
25 use crate::ln::chan_utils;
26 use crate::ln::msgs::DecodeError;
27 use crate::chain::chaininterface::{FeeEstimator, ConfirmationTarget, MIN_RELAY_FEE_SAT_PER_1000_WEIGHT};
28 use crate::sign::WriteableEcdsaChannelSigner;
30 use crate::chain::onchaintx::ExternalHTLCClaim;
31 use crate::chain::onchaintx::OnchainTxHandler;
32 use crate::util::logger::Logger;
33 use crate::util::ser::{Readable, Writer, Writeable, RequiredWrapper};
36 use crate::prelude::*;
39 use core::convert::TryInto;
42 use bitcoin::{PackedLockTime, Sequence, Witness};
43 use crate::ln::features::ChannelTypeFeatures;
45 use super::chaininterface::LowerBoundedFeeEstimator;
47 const MAX_ALLOC_SIZE: usize = 64*1024;
50 pub(crate) fn weight_revoked_offered_htlc(channel_type_features: &ChannelTypeFeatures) -> u64 {
51 // number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
52 const WEIGHT_REVOKED_OFFERED_HTLC: u64 = 1 + 1 + 73 + 1 + 33 + 1 + 133;
53 const WEIGHT_REVOKED_OFFERED_HTLC_ANCHORS: u64 = WEIGHT_REVOKED_OFFERED_HTLC + 3; // + OP_1 + OP_CSV + OP_DROP
54 if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_REVOKED_OFFERED_HTLC_ANCHORS } else { WEIGHT_REVOKED_OFFERED_HTLC }
57 pub(crate) fn weight_revoked_received_htlc(channel_type_features: &ChannelTypeFeatures) -> u64 {
58 // number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
59 const WEIGHT_REVOKED_RECEIVED_HTLC: u64 = 1 + 1 + 73 + 1 + 33 + 1 + 139;
60 const WEIGHT_REVOKED_RECEIVED_HTLC_ANCHORS: u64 = WEIGHT_REVOKED_RECEIVED_HTLC + 3; // + OP_1 + OP_CSV + OP_DROP
61 if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_REVOKED_RECEIVED_HTLC_ANCHORS } else { WEIGHT_REVOKED_RECEIVED_HTLC }
64 pub(crate) fn weight_offered_htlc(channel_type_features: &ChannelTypeFeatures) -> u64 {
65 // number_of_witness_elements + sig_length + counterpartyhtlc_sig + preimage_length + preimage + witness_script_length + witness_script
66 const WEIGHT_OFFERED_HTLC: u64 = 1 + 1 + 73 + 1 + 32 + 1 + 133;
67 const WEIGHT_OFFERED_HTLC_ANCHORS: u64 = WEIGHT_OFFERED_HTLC + 3; // + OP_1 + OP_CSV + OP_DROP
68 if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_OFFERED_HTLC_ANCHORS } else { WEIGHT_OFFERED_HTLC }
71 pub(crate) fn weight_received_htlc(channel_type_features: &ChannelTypeFeatures) -> u64 {
72 // number_of_witness_elements + sig_length + counterpartyhtlc_sig + empty_vec_length + empty_vec + witness_script_length + witness_script
73 const WEIGHT_RECEIVED_HTLC: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 139;
74 const WEIGHT_RECEIVED_HTLC_ANCHORS: u64 = WEIGHT_RECEIVED_HTLC + 3; // + OP_1 + OP_CSV + OP_DROP
75 if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_RECEIVED_HTLC_ANCHORS } else { WEIGHT_RECEIVED_HTLC }
78 /// Verifies deserializable channel type features
79 pub(crate) fn verify_channel_type_features(channel_type_features: &Option<ChannelTypeFeatures>, additional_permitted_features: Option<&ChannelTypeFeatures>) -> Result<(), DecodeError> {
80 if let Some(features) = channel_type_features.as_ref() {
81 if features.requires_unknown_bits() {
82 return Err(DecodeError::UnknownRequiredFeature);
85 let mut supported_feature_set = ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies();
86 supported_feature_set.set_scid_privacy_required();
87 supported_feature_set.set_zero_conf_required();
89 // allow the passing of an additional necessary permitted flag
90 if let Some(additional_permitted_features) = additional_permitted_features {
91 supported_feature_set |= additional_permitted_features;
94 if !features.is_subset(&supported_feature_set) {
95 return Err(DecodeError::UnknownRequiredFeature);
102 // number_of_witness_elements + sig_length + revocation_sig + true_length + op_true + witness_script_length + witness_script
103 pub(crate) const WEIGHT_REVOKED_OUTPUT: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 77;
105 /// Height delay at which transactions are fee-bumped/rebroadcasted with a low priority.
106 const LOW_FREQUENCY_BUMP_INTERVAL: u32 = 15;
107 /// Height delay at which transactions are fee-bumped/rebroadcasted with a middle priority.
108 const MIDDLE_FREQUENCY_BUMP_INTERVAL: u32 = 3;
109 /// Height delay at which transactions are fee-bumped/rebroadcasted with a high priority.
110 const HIGH_FREQUENCY_BUMP_INTERVAL: u32 = 1;
112 /// A struct to describe a revoked output and corresponding information to generate a solving
113 /// witness spending a commitment `to_local` output or a second-stage HTLC transaction output.
115 /// CSV and pubkeys are used as part of a witnessScript redeeming a balance output, amount is used
116 /// as part of the signature hash and revocation secret to generate a satisfying witness.
117 #[derive(Clone, PartialEq, Eq)]
118 pub(crate) struct RevokedOutput {
119 per_commitment_point: PublicKey,
120 counterparty_delayed_payment_base_key: PublicKey,
121 counterparty_htlc_base_key: PublicKey,
122 per_commitment_key: SecretKey,
125 on_counterparty_tx_csv: u16,
126 is_counterparty_balance_on_anchors: Option<()>,
130 pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, per_commitment_key: SecretKey, amount: u64, on_counterparty_tx_csv: u16, is_counterparty_balance_on_anchors: bool) -> Self {
132 per_commitment_point,
133 counterparty_delayed_payment_base_key,
134 counterparty_htlc_base_key,
136 weight: WEIGHT_REVOKED_OUTPUT,
138 on_counterparty_tx_csv,
139 is_counterparty_balance_on_anchors: if is_counterparty_balance_on_anchors { Some(()) } else { None }
144 impl_writeable_tlv_based!(RevokedOutput, {
145 (0, per_commitment_point, required),
146 (2, counterparty_delayed_payment_base_key, required),
147 (4, counterparty_htlc_base_key, required),
148 (6, per_commitment_key, required),
149 (8, weight, required),
150 (10, amount, required),
151 (12, on_counterparty_tx_csv, required),
152 (14, is_counterparty_balance_on_anchors, option)
155 /// A struct to describe a revoked offered output and corresponding information to generate a
158 /// HTLCOuputInCommitment (hash timelock, direction) and pubkeys are used to generate a suitable
161 /// CSV is used as part of a witnessScript redeeming a balance output, amount is used as part
162 /// of the signature hash and revocation secret to generate a satisfying witness.
163 #[derive(Clone, PartialEq, Eq)]
164 pub(crate) struct RevokedHTLCOutput {
165 per_commitment_point: PublicKey,
166 counterparty_delayed_payment_base_key: PublicKey,
167 counterparty_htlc_base_key: PublicKey,
168 per_commitment_key: SecretKey,
171 htlc: HTLCOutputInCommitment,
174 impl RevokedHTLCOutput {
175 pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, per_commitment_key: SecretKey, amount: u64, htlc: HTLCOutputInCommitment, channel_type_features: &ChannelTypeFeatures) -> Self {
176 let weight = if htlc.offered { weight_revoked_offered_htlc(channel_type_features) } else { weight_revoked_received_htlc(channel_type_features) };
178 per_commitment_point,
179 counterparty_delayed_payment_base_key,
180 counterparty_htlc_base_key,
189 impl_writeable_tlv_based!(RevokedHTLCOutput, {
190 (0, per_commitment_point, required),
191 (2, counterparty_delayed_payment_base_key, required),
192 (4, counterparty_htlc_base_key, required),
193 (6, per_commitment_key, required),
194 (8, weight, required),
195 (10, amount, required),
196 (12, htlc, required),
199 /// A struct to describe a HTLC output on a counterparty commitment transaction.
201 /// HTLCOutputInCommitment (hash, timelock, directon) and pubkeys are used to generate a suitable
204 /// The preimage is used as part of the witness.
206 /// Note that on upgrades, some features of existing outputs may be missed.
207 #[derive(Clone, PartialEq, Eq)]
208 pub(crate) struct CounterpartyOfferedHTLCOutput {
209 per_commitment_point: PublicKey,
210 counterparty_delayed_payment_base_key: PublicKey,
211 counterparty_htlc_base_key: PublicKey,
212 preimage: PaymentPreimage,
213 htlc: HTLCOutputInCommitment,
214 channel_type_features: ChannelTypeFeatures,
217 impl CounterpartyOfferedHTLCOutput {
218 pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, preimage: PaymentPreimage, htlc: HTLCOutputInCommitment, channel_type_features: ChannelTypeFeatures) -> Self {
219 CounterpartyOfferedHTLCOutput {
220 per_commitment_point,
221 counterparty_delayed_payment_base_key,
222 counterparty_htlc_base_key,
225 channel_type_features,
230 impl Writeable for CounterpartyOfferedHTLCOutput {
231 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
232 let legacy_deserialization_prevention_marker = chan_utils::legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
233 write_tlv_fields!(writer, {
234 (0, self.per_commitment_point, required),
235 (2, self.counterparty_delayed_payment_base_key, required),
236 (4, self.counterparty_htlc_base_key, required),
237 (6, self.preimage, required),
238 (8, self.htlc, required),
239 (10, legacy_deserialization_prevention_marker, option),
240 (11, self.channel_type_features, required),
246 impl Readable for CounterpartyOfferedHTLCOutput {
247 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
248 let mut per_commitment_point = RequiredWrapper(None);
249 let mut counterparty_delayed_payment_base_key = RequiredWrapper(None);
250 let mut counterparty_htlc_base_key = RequiredWrapper(None);
251 let mut preimage = RequiredWrapper(None);
252 let mut htlc = RequiredWrapper(None);
253 let mut legacy_deserialization_prevention_marker: Option<()> = None;
254 let mut channel_type_features = None;
256 read_tlv_fields!(reader, {
257 (0, per_commitment_point, required),
258 (2, counterparty_delayed_payment_base_key, required),
259 (4, counterparty_htlc_base_key, required),
260 (6, preimage, required),
262 (10, legacy_deserialization_prevention_marker, option),
263 (11, channel_type_features, option),
266 verify_channel_type_features(&channel_type_features, None)?;
269 per_commitment_point: per_commitment_point.0.unwrap(),
270 counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
271 counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
272 preimage: preimage.0.unwrap(),
273 htlc: htlc.0.unwrap(),
274 channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
279 /// A struct to describe a HTLC output on a counterparty commitment transaction.
281 /// HTLCOutputInCommitment (hash, timelock, directon) and pubkeys are used to generate a suitable
284 /// Note that on upgrades, some features of existing outputs may be missed.
285 #[derive(Clone, PartialEq, Eq)]
286 pub(crate) struct CounterpartyReceivedHTLCOutput {
287 per_commitment_point: PublicKey,
288 counterparty_delayed_payment_base_key: PublicKey,
289 counterparty_htlc_base_key: PublicKey,
290 htlc: HTLCOutputInCommitment,
291 channel_type_features: ChannelTypeFeatures,
294 impl CounterpartyReceivedHTLCOutput {
295 pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, htlc: HTLCOutputInCommitment, channel_type_features: ChannelTypeFeatures) -> Self {
296 CounterpartyReceivedHTLCOutput {
297 per_commitment_point,
298 counterparty_delayed_payment_base_key,
299 counterparty_htlc_base_key,
301 channel_type_features
306 impl Writeable for CounterpartyReceivedHTLCOutput {
307 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
308 let legacy_deserialization_prevention_marker = chan_utils::legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
309 write_tlv_fields!(writer, {
310 (0, self.per_commitment_point, required),
311 (2, self.counterparty_delayed_payment_base_key, required),
312 (4, self.counterparty_htlc_base_key, required),
313 (6, self.htlc, required),
314 (8, legacy_deserialization_prevention_marker, option),
315 (9, self.channel_type_features, required),
321 impl Readable for CounterpartyReceivedHTLCOutput {
322 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
323 let mut per_commitment_point = RequiredWrapper(None);
324 let mut counterparty_delayed_payment_base_key = RequiredWrapper(None);
325 let mut counterparty_htlc_base_key = RequiredWrapper(None);
326 let mut htlc = RequiredWrapper(None);
327 let mut legacy_deserialization_prevention_marker: Option<()> = None;
328 let mut channel_type_features = None;
330 read_tlv_fields!(reader, {
331 (0, per_commitment_point, required),
332 (2, counterparty_delayed_payment_base_key, required),
333 (4, counterparty_htlc_base_key, required),
335 (8, legacy_deserialization_prevention_marker, option),
336 (9, channel_type_features, option),
339 verify_channel_type_features(&channel_type_features, None)?;
342 per_commitment_point: per_commitment_point.0.unwrap(),
343 counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
344 counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
345 htlc: htlc.0.unwrap(),
346 channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
351 /// A struct to describe a HTLC output on holder commitment transaction.
353 /// Either offered or received, the amount is always used as part of the bip143 sighash.
354 /// Preimage is only included as part of the witness in former case.
356 /// Note that on upgrades, some features of existing outputs may be missed.
357 #[derive(Clone, PartialEq, Eq)]
358 pub(crate) struct HolderHTLCOutput {
359 preimage: Option<PaymentPreimage>,
361 /// Defaults to 0 for HTLC-Success transactions, which have no expiry
363 channel_type_features: ChannelTypeFeatures,
366 impl HolderHTLCOutput {
367 pub(crate) fn build_offered(amount_msat: u64, cltv_expiry: u32, channel_type_features: ChannelTypeFeatures) -> Self {
372 channel_type_features,
376 pub(crate) fn build_accepted(preimage: PaymentPreimage, amount_msat: u64, channel_type_features: ChannelTypeFeatures) -> Self {
378 preimage: Some(preimage),
381 channel_type_features,
386 impl Writeable for HolderHTLCOutput {
387 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
388 let legacy_deserialization_prevention_marker = chan_utils::legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
389 write_tlv_fields!(writer, {
390 (0, self.amount_msat, required),
391 (2, self.cltv_expiry, required),
392 (4, self.preimage, option),
393 (6, legacy_deserialization_prevention_marker, option),
394 (7, self.channel_type_features, required),
400 impl Readable for HolderHTLCOutput {
401 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
402 let mut amount_msat = RequiredWrapper(None);
403 let mut cltv_expiry = RequiredWrapper(None);
404 let mut preimage = None;
405 let mut legacy_deserialization_prevention_marker: Option<()> = None;
406 let mut channel_type_features = None;
408 read_tlv_fields!(reader, {
409 (0, amount_msat, required),
410 (2, cltv_expiry, required),
411 (4, preimage, option),
412 (6, legacy_deserialization_prevention_marker, option),
413 (7, channel_type_features, option),
416 verify_channel_type_features(&channel_type_features, None)?;
419 amount_msat: amount_msat.0.unwrap(),
420 cltv_expiry: cltv_expiry.0.unwrap(),
422 channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
427 /// A struct to describe the channel output on the funding transaction.
429 /// witnessScript is used as part of the witness redeeming the funding utxo.
431 /// Note that on upgrades, some features of existing outputs may be missed.
432 #[derive(Clone, PartialEq, Eq)]
433 pub(crate) struct HolderFundingOutput {
434 funding_redeemscript: Script,
435 funding_amount: Option<u64>,
436 channel_type_features: ChannelTypeFeatures,
440 impl HolderFundingOutput {
441 pub(crate) fn build(funding_redeemscript: Script, funding_amount: u64, channel_type_features: ChannelTypeFeatures) -> Self {
442 HolderFundingOutput {
443 funding_redeemscript,
444 funding_amount: Some(funding_amount),
445 channel_type_features,
450 impl Writeable for HolderFundingOutput {
451 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
452 let legacy_deserialization_prevention_marker = chan_utils::legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
453 write_tlv_fields!(writer, {
454 (0, self.funding_redeemscript, required),
455 (1, self.channel_type_features, required),
456 (2, legacy_deserialization_prevention_marker, option),
457 (3, self.funding_amount, option),
463 impl Readable for HolderFundingOutput {
464 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
465 let mut funding_redeemscript = RequiredWrapper(None);
466 let mut legacy_deserialization_prevention_marker: Option<()> = None;
467 let mut channel_type_features = None;
468 let mut funding_amount = None;
470 read_tlv_fields!(reader, {
471 (0, funding_redeemscript, required),
472 (1, channel_type_features, option),
473 (2, legacy_deserialization_prevention_marker, option),
474 (3, funding_amount, option)
477 verify_channel_type_features(&channel_type_features, None)?;
480 funding_redeemscript: funding_redeemscript.0.unwrap(),
481 channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key()),
487 /// A wrapper encapsulating all in-protocol differing outputs types.
489 /// The generic API offers access to an outputs common attributes or allow transformation such as
490 /// finalizing an input claiming the output.
491 #[derive(Clone, PartialEq, Eq)]
492 pub(crate) enum PackageSolvingData {
493 RevokedOutput(RevokedOutput),
494 RevokedHTLCOutput(RevokedHTLCOutput),
495 CounterpartyOfferedHTLCOutput(CounterpartyOfferedHTLCOutput),
496 CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput),
497 HolderHTLCOutput(HolderHTLCOutput),
498 HolderFundingOutput(HolderFundingOutput),
501 impl PackageSolvingData {
502 fn amount(&self) -> u64 {
503 let amt = match self {
504 PackageSolvingData::RevokedOutput(ref outp) => outp.amount,
505 PackageSolvingData::RevokedHTLCOutput(ref outp) => outp.amount,
506 PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => outp.htlc.amount_msat / 1000,
507 PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => outp.htlc.amount_msat / 1000,
508 PackageSolvingData::HolderHTLCOutput(ref outp) => {
509 debug_assert!(outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
510 outp.amount_msat / 1000
512 PackageSolvingData::HolderFundingOutput(ref outp) => {
513 debug_assert!(outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
514 outp.funding_amount.unwrap()
519 fn weight(&self) -> usize {
521 PackageSolvingData::RevokedOutput(ref outp) => outp.weight as usize,
522 PackageSolvingData::RevokedHTLCOutput(ref outp) => outp.weight as usize,
523 PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => weight_offered_htlc(&outp.channel_type_features) as usize,
524 PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => weight_received_htlc(&outp.channel_type_features) as usize,
525 PackageSolvingData::HolderHTLCOutput(ref outp) => {
526 debug_assert!(outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
527 if outp.preimage.is_none() {
528 weight_offered_htlc(&outp.channel_type_features) as usize
530 weight_received_htlc(&outp.channel_type_features) as usize
533 // Since HolderFundingOutput maps to an untractable package that is already signed, its
534 // weight can be determined from the transaction itself.
535 PackageSolvingData::HolderFundingOutput(..) => unreachable!(),
538 fn is_compatible(&self, input: &PackageSolvingData) -> bool {
540 PackageSolvingData::RevokedOutput(..) => {
542 PackageSolvingData::RevokedHTLCOutput(..) => { true },
543 PackageSolvingData::RevokedOutput(..) => { true },
547 PackageSolvingData::RevokedHTLCOutput(..) => {
549 PackageSolvingData::RevokedOutput(..) => { true },
550 PackageSolvingData::RevokedHTLCOutput(..) => { true },
554 _ => { mem::discriminant(self) == mem::discriminant(&input) }
557 fn finalize_input<Signer: WriteableEcdsaChannelSigner>(&self, bumped_tx: &mut Transaction, i: usize, onchain_handler: &mut OnchainTxHandler<Signer>) -> bool {
559 PackageSolvingData::RevokedOutput(ref outp) => {
560 let chan_keys = TxCreationKeys::derive_new(&onchain_handler.secp_ctx, &outp.per_commitment_point, &outp.counterparty_delayed_payment_base_key, &outp.counterparty_htlc_base_key, &onchain_handler.signer.pubkeys().revocation_basepoint, &onchain_handler.signer.pubkeys().htlc_basepoint);
561 let witness_script = chan_utils::get_revokeable_redeemscript(&chan_keys.revocation_key, outp.on_counterparty_tx_csv, &chan_keys.broadcaster_delayed_payment_key);
562 //TODO: should we panic on signer failure ?
563 if let Ok(sig) = onchain_handler.signer.sign_justice_revoked_output(&bumped_tx, i, outp.amount, &outp.per_commitment_key, &onchain_handler.secp_ctx) {
564 let mut ser_sig = sig.serialize_der().to_vec();
565 ser_sig.push(EcdsaSighashType::All as u8);
566 bumped_tx.input[i].witness.push(ser_sig);
567 bumped_tx.input[i].witness.push(vec!(1));
568 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
569 } else { return false; }
571 PackageSolvingData::RevokedHTLCOutput(ref outp) => {
572 let chan_keys = TxCreationKeys::derive_new(&onchain_handler.secp_ctx, &outp.per_commitment_point, &outp.counterparty_delayed_payment_base_key, &outp.counterparty_htlc_base_key, &onchain_handler.signer.pubkeys().revocation_basepoint, &onchain_handler.signer.pubkeys().htlc_basepoint);
573 let witness_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&outp.htlc, &onchain_handler.channel_type_features(), &chan_keys.broadcaster_htlc_key, &chan_keys.countersignatory_htlc_key, &chan_keys.revocation_key);
574 //TODO: should we panic on signer failure ?
575 if let Ok(sig) = onchain_handler.signer.sign_justice_revoked_htlc(&bumped_tx, i, outp.amount, &outp.per_commitment_key, &outp.htlc, &onchain_handler.secp_ctx) {
576 let mut ser_sig = sig.serialize_der().to_vec();
577 ser_sig.push(EcdsaSighashType::All as u8);
578 bumped_tx.input[i].witness.push(ser_sig);
579 bumped_tx.input[i].witness.push(chan_keys.revocation_key.clone().serialize().to_vec());
580 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
581 } else { return false; }
583 PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => {
584 let chan_keys = TxCreationKeys::derive_new(&onchain_handler.secp_ctx, &outp.per_commitment_point, &outp.counterparty_delayed_payment_base_key, &outp.counterparty_htlc_base_key, &onchain_handler.signer.pubkeys().revocation_basepoint, &onchain_handler.signer.pubkeys().htlc_basepoint);
585 let witness_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&outp.htlc, &onchain_handler.channel_type_features(), &chan_keys.broadcaster_htlc_key, &chan_keys.countersignatory_htlc_key, &chan_keys.revocation_key);
587 if let Ok(sig) = onchain_handler.signer.sign_counterparty_htlc_transaction(&bumped_tx, i, &outp.htlc.amount_msat / 1000, &outp.per_commitment_point, &outp.htlc, &onchain_handler.secp_ctx) {
588 let mut ser_sig = sig.serialize_der().to_vec();
589 ser_sig.push(EcdsaSighashType::All as u8);
590 bumped_tx.input[i].witness.push(ser_sig);
591 bumped_tx.input[i].witness.push(outp.preimage.0.to_vec());
592 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
595 PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => {
596 let chan_keys = TxCreationKeys::derive_new(&onchain_handler.secp_ctx, &outp.per_commitment_point, &outp.counterparty_delayed_payment_base_key, &outp.counterparty_htlc_base_key, &onchain_handler.signer.pubkeys().revocation_basepoint, &onchain_handler.signer.pubkeys().htlc_basepoint);
597 let witness_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&outp.htlc, &onchain_handler.channel_type_features(), &chan_keys.broadcaster_htlc_key, &chan_keys.countersignatory_htlc_key, &chan_keys.revocation_key);
599 if let Ok(sig) = onchain_handler.signer.sign_counterparty_htlc_transaction(&bumped_tx, i, &outp.htlc.amount_msat / 1000, &outp.per_commitment_point, &outp.htlc, &onchain_handler.secp_ctx) {
600 let mut ser_sig = sig.serialize_der().to_vec();
601 ser_sig.push(EcdsaSighashType::All as u8);
602 bumped_tx.input[i].witness.push(ser_sig);
603 // Due to BIP146 (MINIMALIF) this must be a zero-length element to relay.
604 bumped_tx.input[i].witness.push(vec![]);
605 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
608 _ => { panic!("API Error!"); }
612 fn get_finalized_tx<Signer: WriteableEcdsaChannelSigner>(&self, outpoint: &BitcoinOutPoint, onchain_handler: &mut OnchainTxHandler<Signer>) -> Option<Transaction> {
614 PackageSolvingData::HolderHTLCOutput(ref outp) => {
615 debug_assert!(!outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
616 return onchain_handler.get_fully_signed_htlc_tx(outpoint, &outp.preimage);
618 PackageSolvingData::HolderFundingOutput(ref outp) => {
619 return Some(onchain_handler.get_fully_signed_holder_tx(&outp.funding_redeemscript));
621 _ => { panic!("API Error!"); }
624 fn absolute_tx_timelock(&self, current_height: u32) -> u32 {
625 // We use `current_height` as our default locktime to discourage fee sniping and because
626 // transactions with it always propagate.
627 let absolute_timelock = match self {
628 PackageSolvingData::RevokedOutput(_) => current_height,
629 PackageSolvingData::RevokedHTLCOutput(_) => current_height,
630 PackageSolvingData::CounterpartyOfferedHTLCOutput(_) => current_height,
631 PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => cmp::max(outp.htlc.cltv_expiry, current_height),
632 // HTLC timeout/success transactions rely on a fixed timelock due to the counterparty's
634 PackageSolvingData::HolderHTLCOutput(ref outp) => {
635 if outp.preimage.is_some() {
636 debug_assert_eq!(outp.cltv_expiry, 0);
640 PackageSolvingData::HolderFundingOutput(_) => current_height,
645 fn map_output_type_flags(&self) -> (PackageMalleability, bool) {
646 // Post-anchor, aggregation of outputs of different types is unsafe. See https://github.com/lightning/bolts/pull/803.
647 let (malleability, aggregable) = match self {
648 PackageSolvingData::RevokedOutput(RevokedOutput { is_counterparty_balance_on_anchors: Some(()), .. }) => { (PackageMalleability::Malleable, false) },
649 PackageSolvingData::RevokedOutput(RevokedOutput { is_counterparty_balance_on_anchors: None, .. }) => { (PackageMalleability::Malleable, true) },
650 PackageSolvingData::RevokedHTLCOutput(..) => { (PackageMalleability::Malleable, true) },
651 PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { (PackageMalleability::Malleable, true) },
652 PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { (PackageMalleability::Malleable, false) },
653 PackageSolvingData::HolderHTLCOutput(ref outp) => if outp.channel_type_features.supports_anchors_zero_fee_htlc_tx() {
654 (PackageMalleability::Malleable, outp.preimage.is_some())
656 (PackageMalleability::Untractable, false)
658 PackageSolvingData::HolderFundingOutput(..) => { (PackageMalleability::Untractable, false) },
660 (malleability, aggregable)
664 impl_writeable_tlv_based_enum!(PackageSolvingData, ;
666 (1, RevokedHTLCOutput),
667 (2, CounterpartyOfferedHTLCOutput),
668 (3, CounterpartyReceivedHTLCOutput),
669 (4, HolderHTLCOutput),
670 (5, HolderFundingOutput),
673 /// A malleable package might be aggregated with other packages to save on fees.
674 /// A untractable package has been counter-signed and aggregable will break cached counterparty signatures.
675 #[derive(Clone, PartialEq, Eq)]
676 pub(crate) enum PackageMalleability {
681 /// A structure to describe a package content that is generated by ChannelMonitor and
682 /// used by OnchainTxHandler to generate and broadcast transactions settling onchain claims.
684 /// A package is defined as one or more transactions claiming onchain outputs in reaction
685 /// to confirmation of a channel transaction. Those packages might be aggregated to save on
686 /// fees, if satisfaction of outputs's witnessScript let's us do so.
688 /// As packages are time-sensitive, we fee-bump and rebroadcast them at scheduled intervals.
689 /// Failing to confirm a package translate as a loss of funds for the user.
690 #[derive(Clone, PartialEq, Eq)]
691 pub struct PackageTemplate {
692 // List of onchain outputs and solving data to generate satisfying witnesses.
693 inputs: Vec<(BitcoinOutPoint, PackageSolvingData)>,
694 // Packages are deemed as malleable if we have local knwoledge of at least one set of
695 // private keys yielding a satisfying witnesses. Malleability implies that we can aggregate
696 // packages among them to save on fees or rely on RBF to bump their feerates.
697 // Untractable packages have been counter-signed and thus imply that we can't aggregate
698 // them without breaking signatures. Fee-bumping strategy will also rely on CPFP.
699 malleability: PackageMalleability,
700 // Block height after which the earlier-output belonging to this package is mature for a
701 // competing claim by the counterparty. As our chain tip becomes nearer from the timelock,
702 // the fee-bumping frequency will increase. See `OnchainTxHandler::get_height_timer`.
703 soonest_conf_deadline: u32,
704 // Determines if this package can be aggregated.
705 // Timelocked outputs belonging to the same transaction might have differing
706 // satisfying heights. Picking up the later height among the output set would be a valid
707 // aggregable strategy but it comes with at least 2 trade-offs :
708 // * earlier-output fund are going to take longer to come back
709 // * CLTV delta backing up a corresponding HTLC on an upstream channel could be swallowed
710 // by the requirement of the later-output part of the set
711 // For now, we mark such timelocked outputs as non-aggregable, though we might introduce
712 // smarter aggregable strategy in the future.
714 // Cache of package feerate committed at previous (re)broadcast. If bumping resources
715 // (either claimed output value or external utxo), it will keep increasing until holder
716 // or counterparty successful claim.
717 feerate_previous: u64,
718 // Cache of next height at which fee-bumping and rebroadcast will be attempted. In
719 // the future, we might abstract it to an observed mempool fluctuation.
721 // Confirmation height of the claimed outputs set transaction. In case of reorg reaching
722 // it, we wipe out and forget the package.
723 height_original: u32,
726 impl PackageTemplate {
727 pub(crate) fn is_malleable(&self) -> bool {
728 self.malleability == PackageMalleability::Malleable
730 pub(crate) fn timelock(&self) -> u32 {
731 self.soonest_conf_deadline
733 pub(crate) fn aggregable(&self) -> bool {
736 pub(crate) fn previous_feerate(&self) -> u64 {
737 self.feerate_previous
739 pub(crate) fn set_feerate(&mut self, new_feerate: u64) {
740 self.feerate_previous = new_feerate;
742 pub(crate) fn timer(&self) -> u32 {
745 pub(crate) fn set_timer(&mut self, new_timer: u32) {
746 self.height_timer = new_timer;
748 pub(crate) fn outpoints(&self) -> Vec<&BitcoinOutPoint> {
749 self.inputs.iter().map(|(o, _)| o).collect()
751 pub(crate) fn inputs(&self) -> impl ExactSizeIterator<Item = &PackageSolvingData> {
752 self.inputs.iter().map(|(_, i)| i)
754 pub(crate) fn split_package(&mut self, split_outp: &BitcoinOutPoint) -> Option<PackageTemplate> {
755 match self.malleability {
756 PackageMalleability::Malleable => {
757 let mut split_package = None;
758 let timelock = self.soonest_conf_deadline;
759 let aggregable = self.aggregable;
760 let feerate_previous = self.feerate_previous;
761 let height_timer = self.height_timer;
762 let height_original = self.height_original;
763 self.inputs.retain(|outp| {
764 if *split_outp == outp.0 {
765 split_package = Some(PackageTemplate {
766 inputs: vec![(outp.0, outp.1.clone())],
767 malleability: PackageMalleability::Malleable,
768 soonest_conf_deadline: timelock,
778 return split_package;
781 // Note, we may try to split on remote transaction for
782 // which we don't have a competing one (HTLC-Success before
783 // timelock expiration). This explain we don't panic!
784 // We should refactor OnchainTxHandler::block_connected to
785 // only test equality on competing claims.
790 pub(crate) fn merge_package(&mut self, mut merge_from: PackageTemplate) {
791 assert_eq!(self.height_original, merge_from.height_original);
792 if self.malleability == PackageMalleability::Untractable || merge_from.malleability == PackageMalleability::Untractable {
793 panic!("Merging template on untractable packages");
795 if !self.aggregable || !merge_from.aggregable {
796 panic!("Merging non aggregatable packages");
798 if let Some((_, lead_input)) = self.inputs.first() {
799 for (_, v) in merge_from.inputs.iter() {
800 if !lead_input.is_compatible(v) { panic!("Merging outputs from differing types !"); }
802 } else { panic!("Merging template on an empty package"); }
803 for (k, v) in merge_from.inputs.drain(..) {
804 self.inputs.push((k, v));
806 //TODO: verify coverage and sanity?
807 if self.soonest_conf_deadline > merge_from.soonest_conf_deadline {
808 self.soonest_conf_deadline = merge_from.soonest_conf_deadline;
810 if self.feerate_previous > merge_from.feerate_previous {
811 self.feerate_previous = merge_from.feerate_previous;
813 self.height_timer = cmp::min(self.height_timer, merge_from.height_timer);
815 /// Gets the amount of all outptus being spent by this package, only valid for malleable
817 pub(crate) fn package_amount(&self) -> u64 {
819 for (_, outp) in self.inputs.iter() {
820 amounts += outp.amount();
824 pub(crate) fn package_locktime(&self, current_height: u32) -> u32 {
825 let locktime = self.inputs.iter().map(|(_, outp)| outp.absolute_tx_timelock(current_height))
826 .max().expect("There must always be at least one output to spend in a PackageTemplate");
828 // If we ever try to aggregate a `HolderHTLCOutput`s with another output type, we'll likely
829 // end up with an incorrect transaction locktime since the counterparty has included it in
830 // its HTLC signature. This should never happen unless we decide to aggregate outputs across
831 // different channel commitments.
832 #[cfg(debug_assertions)] {
833 if self.inputs.iter().any(|(_, outp)|
834 if let PackageSolvingData::HolderHTLCOutput(outp) = outp {
835 outp.preimage.is_some()
840 debug_assert_eq!(locktime, 0);
842 for timeout_htlc_expiry in self.inputs.iter().filter_map(|(_, outp)|
843 if let PackageSolvingData::HolderHTLCOutput(outp) = outp {
844 if outp.preimage.is_none() {
845 Some(outp.cltv_expiry)
849 debug_assert_eq!(locktime, timeout_htlc_expiry);
855 pub(crate) fn package_weight(&self, destination_script: &Script) -> usize {
856 let mut inputs_weight = 0;
857 let mut witnesses_weight = 2; // count segwit flags
858 for (_, outp) in self.inputs.iter() {
859 // previous_out_point: 36 bytes ; var_int: 1 byte ; sequence: 4 bytes
860 inputs_weight += 41 * WITNESS_SCALE_FACTOR;
861 witnesses_weight += outp.weight();
863 // version: 4 bytes ; count_tx_in: 1 byte ; count_tx_out: 1 byte ; lock_time: 4 bytes
864 let transaction_weight = 10 * WITNESS_SCALE_FACTOR;
865 // value: 8 bytes ; var_int: 1 byte ; pk_script: `destination_script.len()`
866 let output_weight = (8 + 1 + destination_script.len()) * WITNESS_SCALE_FACTOR;
867 inputs_weight + witnesses_weight + transaction_weight + output_weight
870 pub(crate) fn construct_malleable_package_with_external_funding<Signer: WriteableEcdsaChannelSigner>(
871 &self, onchain_handler: &mut OnchainTxHandler<Signer>,
872 ) -> Option<Vec<ExternalHTLCClaim>> {
873 debug_assert!(self.requires_external_funding());
874 let mut htlcs: Option<Vec<ExternalHTLCClaim>> = None;
875 for (previous_output, input) in &self.inputs {
877 PackageSolvingData::HolderHTLCOutput(ref outp) => {
878 debug_assert!(outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
879 onchain_handler.generate_external_htlc_claim(&previous_output, &outp.preimage).map(|htlc| {
880 htlcs.get_or_insert_with(|| Vec::with_capacity(self.inputs.len())).push(htlc);
883 _ => debug_assert!(false, "Expected HolderHTLCOutputs to not be aggregated with other input types"),
888 pub(crate) fn finalize_malleable_package<L: Deref, Signer: WriteableEcdsaChannelSigner>(
889 &self, current_height: u32, onchain_handler: &mut OnchainTxHandler<Signer>, value: u64,
890 destination_script: Script, logger: &L
891 ) -> Option<Transaction> where L::Target: Logger {
892 debug_assert!(self.is_malleable());
893 let mut bumped_tx = Transaction {
895 lock_time: PackedLockTime(self.package_locktime(current_height)),
898 script_pubkey: destination_script,
902 for (outpoint, _) in self.inputs.iter() {
903 bumped_tx.input.push(TxIn {
904 previous_output: *outpoint,
905 script_sig: Script::new(),
906 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
907 witness: Witness::new(),
910 for (i, (outpoint, out)) in self.inputs.iter().enumerate() {
911 log_debug!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout);
912 if !out.finalize_input(&mut bumped_tx, i, onchain_handler) { return None; }
914 log_debug!(logger, "Finalized transaction {} ready to broadcast", bumped_tx.txid());
917 pub(crate) fn finalize_untractable_package<L: Deref, Signer: WriteableEcdsaChannelSigner>(
918 &self, onchain_handler: &mut OnchainTxHandler<Signer>, logger: &L,
919 ) -> Option<Transaction> where L::Target: Logger {
920 debug_assert!(!self.is_malleable());
921 if let Some((outpoint, outp)) = self.inputs.first() {
922 if let Some(final_tx) = outp.get_finalized_tx(outpoint, onchain_handler) {
923 log_debug!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout);
924 log_debug!(logger, "Finalized transaction {} ready to broadcast", final_tx.txid());
925 return Some(final_tx);
928 } else { panic!("API Error: Package must not be inputs empty"); }
930 /// In LN, output claimed are time-sensitive, which means we have to spend them before reaching some timelock expiration. At in-channel
931 /// output detection, we generate a first version of a claim tx and associate to it a height timer. A height timer is an absolute block
932 /// height that once reached we should generate a new bumped "version" of the claim tx to be sure that we safely claim outputs before
933 /// that our counterparty can do so. If timelock expires soon, height timer is going to be scaled down in consequence to increase
934 /// frequency of the bump and so increase our bets of success.
935 pub(crate) fn get_height_timer(&self, current_height: u32) -> u32 {
936 if self.soonest_conf_deadline <= current_height + MIDDLE_FREQUENCY_BUMP_INTERVAL {
937 return current_height + HIGH_FREQUENCY_BUMP_INTERVAL
938 } else if self.soonest_conf_deadline - current_height <= LOW_FREQUENCY_BUMP_INTERVAL {
939 return current_height + MIDDLE_FREQUENCY_BUMP_INTERVAL
941 current_height + LOW_FREQUENCY_BUMP_INTERVAL
944 /// Returns value in satoshis to be included as package outgoing output amount and feerate
945 /// which was used to generate the value. Will not return less than `dust_limit_sats` for the
947 pub(crate) fn compute_package_output<F: Deref, L: Deref>(
948 &self, predicted_weight: usize, dust_limit_sats: u64, force_feerate_bump: bool,
949 fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L,
950 ) -> Option<(u64, u64)>
952 F::Target: FeeEstimator,
955 debug_assert!(self.malleability == PackageMalleability::Malleable, "The package output is fixed for non-malleable packages");
956 let input_amounts = self.package_amount();
957 assert!(dust_limit_sats as i64 > 0, "Output script must be broadcastable/have a 'real' dust limit.");
958 // If old feerate is 0, first iteration of this claim, use normal fee calculation
959 if self.feerate_previous != 0 {
960 if let Some((new_fee, feerate)) = feerate_bump(
961 predicted_weight, input_amounts, self.feerate_previous, force_feerate_bump,
962 fee_estimator, logger,
964 return Some((cmp::max(input_amounts as i64 - new_fee as i64, dust_limit_sats as i64) as u64, feerate));
967 if let Some((new_fee, feerate)) = compute_fee_from_spent_amounts(input_amounts, predicted_weight, fee_estimator, logger) {
968 return Some((cmp::max(input_amounts as i64 - new_fee as i64, dust_limit_sats as i64) as u64, feerate));
975 /// Computes a feerate based on the given confirmation target. If a previous feerate was used,
976 /// the new feerate is below it, and `force_feerate_bump` is set, we'll use a 25% increase of
977 /// the previous feerate instead of the new feerate.
978 pub(crate) fn compute_package_feerate<F: Deref>(
979 &self, fee_estimator: &LowerBoundedFeeEstimator<F>, conf_target: ConfirmationTarget,
980 force_feerate_bump: bool,
981 ) -> u32 where F::Target: FeeEstimator {
982 let feerate_estimate = fee_estimator.bounded_sat_per_1000_weight(conf_target);
983 if self.feerate_previous != 0 {
984 // If old feerate inferior to actual one given back by Fee Estimator, use it to compute new fee...
985 if feerate_estimate as u64 > self.feerate_previous {
987 } else if !force_feerate_bump {
988 self.feerate_previous.try_into().unwrap_or(u32::max_value())
990 // ...else just increase the previous feerate by 25% (because that's a nice number)
991 (self.feerate_previous + (self.feerate_previous / 4)).try_into().unwrap_or(u32::max_value())
998 /// Determines whether a package contains an input which must have additional external inputs
999 /// attached to help the spending transaction reach confirmation.
1000 pub(crate) fn requires_external_funding(&self) -> bool {
1001 self.inputs.iter().find(|input| match input.1 {
1002 PackageSolvingData::HolderFundingOutput(ref outp) => outp.channel_type_features.supports_anchors_zero_fee_htlc_tx(),
1003 PackageSolvingData::HolderHTLCOutput(ref outp) => outp.channel_type_features.supports_anchors_zero_fee_htlc_tx(),
1008 pub (crate) fn build_package(txid: Txid, vout: u32, input_solving_data: PackageSolvingData, soonest_conf_deadline: u32, height_original: u32) -> Self {
1009 let (malleability, aggregable) = PackageSolvingData::map_output_type_flags(&input_solving_data);
1010 let mut inputs = Vec::with_capacity(1);
1011 inputs.push((BitcoinOutPoint { txid, vout }, input_solving_data));
1015 soonest_conf_deadline,
1017 feerate_previous: 0,
1018 height_timer: height_original,
1024 impl Writeable for PackageTemplate {
1025 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1026 writer.write_all(&(self.inputs.len() as u64).to_be_bytes())?;
1027 for (ref outpoint, ref rev_outp) in self.inputs.iter() {
1028 outpoint.write(writer)?;
1029 rev_outp.write(writer)?;
1031 write_tlv_fields!(writer, {
1032 (0, self.soonest_conf_deadline, required),
1033 (2, self.feerate_previous, required),
1034 (4, self.height_original, required),
1035 (6, self.height_timer, required)
1041 impl Readable for PackageTemplate {
1042 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
1043 let inputs_count = <u64 as Readable>::read(reader)?;
1044 let mut inputs: Vec<(BitcoinOutPoint, PackageSolvingData)> = Vec::with_capacity(cmp::min(inputs_count as usize, MAX_ALLOC_SIZE / 128));
1045 for _ in 0..inputs_count {
1046 let outpoint = Readable::read(reader)?;
1047 let rev_outp = Readable::read(reader)?;
1048 inputs.push((outpoint, rev_outp));
1050 let (malleability, aggregable) = if let Some((_, lead_input)) = inputs.first() {
1051 PackageSolvingData::map_output_type_flags(&lead_input)
1052 } else { return Err(DecodeError::InvalidValue); };
1053 let mut soonest_conf_deadline = 0;
1054 let mut feerate_previous = 0;
1055 let mut height_timer = None;
1056 let mut height_original = 0;
1057 read_tlv_fields!(reader, {
1058 (0, soonest_conf_deadline, required),
1059 (2, feerate_previous, required),
1060 (4, height_original, required),
1061 (6, height_timer, option),
1063 if height_timer.is_none() {
1064 height_timer = Some(height_original);
1066 Ok(PackageTemplate {
1069 soonest_conf_deadline,
1072 height_timer: height_timer.unwrap(),
1078 /// Attempt to propose a bumping fee for a transaction from its spent output's values and predicted
1079 /// weight. We start with the highest priority feerate returned by the node's fee estimator then
1080 /// fall-back to lower priorities until we have enough value available to suck from.
1082 /// If the proposed fee is less than the available spent output's values, we return the proposed
1083 /// fee and the corresponding updated feerate. If the proposed fee is equal or more than the
1084 /// available spent output's values, we return nothing
1085 fn compute_fee_from_spent_amounts<F: Deref, L: Deref>(input_amounts: u64, predicted_weight: usize, fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L) -> Option<(u64, u64)>
1086 where F::Target: FeeEstimator,
1089 let mut updated_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64;
1090 let mut fee = updated_feerate * (predicted_weight as u64) / 1000;
1091 if input_amounts <= fee {
1092 updated_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Normal) as u64;
1093 fee = updated_feerate * (predicted_weight as u64) / 1000;
1094 if input_amounts <= fee {
1095 updated_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Background) as u64;
1096 fee = updated_feerate * (predicted_weight as u64) / 1000;
1097 if input_amounts <= fee {
1098 log_error!(logger, "Failed to generate an on-chain punishment tx as even low priority fee ({} sat) was more than the entire claim balance ({} sat)",
1099 fee, input_amounts);
1102 log_warn!(logger, "Used low priority fee for on-chain punishment tx as high priority fee was more than the entire claim balance ({} sat)",
1104 Some((fee, updated_feerate))
1107 log_warn!(logger, "Used medium priority fee for on-chain punishment tx as high priority fee was more than the entire claim balance ({} sat)",
1109 Some((fee, updated_feerate))
1112 Some((fee, updated_feerate))
1116 /// Attempt to propose a bumping fee for a transaction from its spent output's values and predicted
1117 /// weight. If feerates proposed by the fee-estimator have been increasing since last fee-bumping
1118 /// attempt, use them. If `force_feerate_bump` is set, we bump the feerate by 25% of the previous
1119 /// feerate, or just use the previous feerate otherwise. If a feerate bump did happen, we also
1120 /// verify that those bumping heuristics respect BIP125 rules 3) and 4) and if required adjust the
1121 /// new fee to meet the RBF policy requirement.
1122 fn feerate_bump<F: Deref, L: Deref>(
1123 predicted_weight: usize, input_amounts: u64, previous_feerate: u64, force_feerate_bump: bool,
1124 fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L,
1125 ) -> Option<(u64, u64)>
1127 F::Target: FeeEstimator,
1130 // If old feerate inferior to actual one given back by Fee Estimator, use it to compute new fee...
1131 let (new_fee, new_feerate) = if let Some((new_fee, new_feerate)) = compute_fee_from_spent_amounts(input_amounts, predicted_weight, fee_estimator, logger) {
1132 if new_feerate > previous_feerate {
1133 (new_fee, new_feerate)
1134 } else if !force_feerate_bump {
1135 let previous_fee = previous_feerate * (predicted_weight as u64) / 1000;
1136 (previous_fee, previous_feerate)
1138 // ...else just increase the previous feerate by 25% (because that's a nice number)
1139 let bumped_feerate = previous_feerate + (previous_feerate / 4);
1140 let bumped_fee = bumped_feerate * (predicted_weight as u64) / 1000;
1141 if input_amounts <= bumped_fee {
1142 log_warn!(logger, "Can't 25% bump new claiming tx, amount {} is too small", input_amounts);
1145 (bumped_fee, bumped_feerate)
1148 log_warn!(logger, "Can't new-estimation bump new claiming tx, amount {} is too small", input_amounts);
1152 // Our feerates should never decrease. If it hasn't changed though, we just need to
1153 // rebroadcast/re-sign the previous claim.
1154 debug_assert!(new_feerate >= previous_feerate);
1155 if new_feerate == previous_feerate {
1156 return Some((new_fee, new_feerate));
1159 let previous_fee = previous_feerate * (predicted_weight as u64) / 1000;
1160 let min_relay_fee = MIN_RELAY_FEE_SAT_PER_1000_WEIGHT * (predicted_weight as u64) / 1000;
1161 // BIP 125 Opt-in Full Replace-by-Fee Signaling
1162 // * 3. The replacement transaction pays an absolute fee of at least the sum paid by the original transactions.
1163 // * 4. The replacement transaction must also pay for its own bandwidth at or above the rate set by the node's minimum relay fee setting.
1164 let new_fee = if new_fee < previous_fee + min_relay_fee {
1165 new_fee + previous_fee + min_relay_fee - new_fee
1169 Some((new_fee, new_fee * 1000 / (predicted_weight as u64)))
1174 use crate::chain::package::{CounterpartyOfferedHTLCOutput, CounterpartyReceivedHTLCOutput, HolderHTLCOutput, PackageTemplate, PackageSolvingData, RevokedOutput, WEIGHT_REVOKED_OUTPUT, weight_offered_htlc, weight_received_htlc};
1175 use crate::chain::Txid;
1176 use crate::ln::chan_utils::HTLCOutputInCommitment;
1177 use crate::ln::{PaymentPreimage, PaymentHash};
1179 use bitcoin::blockdata::constants::WITNESS_SCALE_FACTOR;
1180 use bitcoin::blockdata::script::Script;
1181 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
1183 use bitcoin::hashes::hex::FromHex;
1185 use bitcoin::secp256k1::{PublicKey,SecretKey};
1186 use bitcoin::secp256k1::Secp256k1;
1187 use crate::ln::features::ChannelTypeFeatures;
1189 macro_rules! dumb_revk_output {
1190 ($secp_ctx: expr, $is_counterparty_balance_on_anchors: expr) => {
1192 let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
1193 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
1194 PackageSolvingData::RevokedOutput(RevokedOutput::build(dumb_point, dumb_point, dumb_point, dumb_scalar, 0, 0, $is_counterparty_balance_on_anchors))
1199 macro_rules! dumb_counterparty_output {
1200 ($secp_ctx: expr, $amt: expr, $opt_anchors: expr) => {
1202 let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
1203 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
1204 let hash = PaymentHash([1; 32]);
1205 let htlc = HTLCOutputInCommitment { offered: true, amount_msat: $amt, cltv_expiry: 0, payment_hash: hash, transaction_output_index: None };
1206 PackageSolvingData::CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput::build(dumb_point, dumb_point, dumb_point, htlc, $opt_anchors))
1211 macro_rules! dumb_counterparty_offered_output {
1212 ($secp_ctx: expr, $amt: expr, $opt_anchors: expr) => {
1214 let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
1215 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
1216 let hash = PaymentHash([1; 32]);
1217 let preimage = PaymentPreimage([2;32]);
1218 let htlc = HTLCOutputInCommitment { offered: false, amount_msat: $amt, cltv_expiry: 1000, payment_hash: hash, transaction_output_index: None };
1219 PackageSolvingData::CounterpartyOfferedHTLCOutput(CounterpartyOfferedHTLCOutput::build(dumb_point, dumb_point, dumb_point, preimage, htlc, $opt_anchors))
1224 macro_rules! dumb_htlc_output {
1227 let preimage = PaymentPreimage([2;32]);
1228 PackageSolvingData::HolderHTLCOutput(HolderHTLCOutput::build_accepted(preimage, 0, ChannelTypeFeatures::only_static_remote_key()))
1235 fn test_package_differing_heights() {
1236 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1237 let secp_ctx = Secp256k1::new();
1238 let revk_outp = dumb_revk_output!(secp_ctx, false);
1240 let mut package_one_hundred = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, 100);
1241 let package_two_hundred = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, 200);
1242 package_one_hundred.merge_package(package_two_hundred);
1247 fn test_package_untractable_merge_to() {
1248 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1249 let secp_ctx = Secp256k1::new();
1250 let revk_outp = dumb_revk_output!(secp_ctx, false);
1251 let htlc_outp = dumb_htlc_output!();
1253 let mut untractable_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, 100);
1254 let malleable_package = PackageTemplate::build_package(txid, 1, htlc_outp.clone(), 1000, 100);
1255 untractable_package.merge_package(malleable_package);
1260 fn test_package_untractable_merge_from() {
1261 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1262 let secp_ctx = Secp256k1::new();
1263 let htlc_outp = dumb_htlc_output!();
1264 let revk_outp = dumb_revk_output!(secp_ctx, false);
1266 let mut malleable_package = PackageTemplate::build_package(txid, 0, htlc_outp.clone(), 1000, 100);
1267 let untractable_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, 100);
1268 malleable_package.merge_package(untractable_package);
1273 fn test_package_noaggregation_to() {
1274 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1275 let secp_ctx = Secp256k1::new();
1276 let revk_outp = dumb_revk_output!(secp_ctx, false);
1277 let revk_outp_counterparty_balance = dumb_revk_output!(secp_ctx, true);
1279 let mut noaggregation_package = PackageTemplate::build_package(txid, 0, revk_outp_counterparty_balance.clone(), 1000, 100);
1280 let aggregation_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, 100);
1281 noaggregation_package.merge_package(aggregation_package);
1286 fn test_package_noaggregation_from() {
1287 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1288 let secp_ctx = Secp256k1::new();
1289 let revk_outp = dumb_revk_output!(secp_ctx, false);
1290 let revk_outp_counterparty_balance = dumb_revk_output!(secp_ctx, true);
1292 let mut aggregation_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, 100);
1293 let noaggregation_package = PackageTemplate::build_package(txid, 1, revk_outp_counterparty_balance.clone(), 1000, 100);
1294 aggregation_package.merge_package(noaggregation_package);
1299 fn test_package_empty() {
1300 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1301 let secp_ctx = Secp256k1::new();
1302 let revk_outp = dumb_revk_output!(secp_ctx, false);
1304 let mut empty_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, 100);
1305 empty_package.inputs = vec![];
1306 let package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, 100);
1307 empty_package.merge_package(package);
1312 fn test_package_differing_categories() {
1313 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1314 let secp_ctx = Secp256k1::new();
1315 let revk_outp = dumb_revk_output!(secp_ctx, false);
1316 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 0, ChannelTypeFeatures::only_static_remote_key());
1318 let mut revoked_package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, 100);
1319 let counterparty_package = PackageTemplate::build_package(txid, 1, counterparty_outp, 1000, 100);
1320 revoked_package.merge_package(counterparty_package);
1324 fn test_package_split_malleable() {
1325 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1326 let secp_ctx = Secp256k1::new();
1327 let revk_outp_one = dumb_revk_output!(secp_ctx, false);
1328 let revk_outp_two = dumb_revk_output!(secp_ctx, false);
1329 let revk_outp_three = dumb_revk_output!(secp_ctx, false);
1331 let mut package_one = PackageTemplate::build_package(txid, 0, revk_outp_one, 1000, 100);
1332 let package_two = PackageTemplate::build_package(txid, 1, revk_outp_two, 1000, 100);
1333 let package_three = PackageTemplate::build_package(txid, 2, revk_outp_three, 1000, 100);
1335 package_one.merge_package(package_two);
1336 package_one.merge_package(package_three);
1337 assert_eq!(package_one.outpoints().len(), 3);
1339 if let Some(split_package) = package_one.split_package(&BitcoinOutPoint { txid, vout: 1 }) {
1340 // Packages attributes should be identical
1341 assert!(split_package.is_malleable());
1342 assert_eq!(split_package.soonest_conf_deadline, package_one.soonest_conf_deadline);
1343 assert_eq!(split_package.aggregable, package_one.aggregable);
1344 assert_eq!(split_package.feerate_previous, package_one.feerate_previous);
1345 assert_eq!(split_package.height_timer, package_one.height_timer);
1346 assert_eq!(split_package.height_original, package_one.height_original);
1347 } else { panic!(); }
1348 assert_eq!(package_one.outpoints().len(), 2);
1352 fn test_package_split_untractable() {
1353 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1354 let htlc_outp_one = dumb_htlc_output!();
1356 let mut package_one = PackageTemplate::build_package(txid, 0, htlc_outp_one, 1000, 100);
1357 let ret_split = package_one.split_package(&BitcoinOutPoint { txid, vout: 0});
1358 assert!(ret_split.is_none());
1362 fn test_package_timer() {
1363 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1364 let secp_ctx = Secp256k1::new();
1365 let revk_outp = dumb_revk_output!(secp_ctx, false);
1367 let mut package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, 100);
1368 assert_eq!(package.timer(), 100);
1369 package.set_timer(101);
1370 assert_eq!(package.timer(), 101);
1374 fn test_package_amounts() {
1375 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1376 let secp_ctx = Secp256k1::new();
1377 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 1_000_000, ChannelTypeFeatures::only_static_remote_key());
1379 let package = PackageTemplate::build_package(txid, 0, counterparty_outp, 1000, 100);
1380 assert_eq!(package.package_amount(), 1000);
1384 fn test_package_weight() {
1385 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1386 let secp_ctx = Secp256k1::new();
1388 // (nVersion (4) + nLocktime (4) + count_tx_in (1) + prevout (36) + sequence (4) + script_length (1) + count_tx_out (1) + value (8) + var_int (1)) * WITNESS_SCALE_FACTOR + witness marker (2)
1389 let weight_sans_output = (4 + 4 + 1 + 36 + 4 + 1 + 1 + 8 + 1) * WITNESS_SCALE_FACTOR + 2;
1392 let revk_outp = dumb_revk_output!(secp_ctx, false);
1393 let package = PackageTemplate::build_package(txid, 0, revk_outp, 0, 100);
1394 assert_eq!(package.package_weight(&Script::new()), weight_sans_output + WEIGHT_REVOKED_OUTPUT as usize);
1398 for channel_type_features in [ChannelTypeFeatures::only_static_remote_key(), ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()].iter() {
1399 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 1_000_000, channel_type_features.clone());
1400 let package = PackageTemplate::build_package(txid, 0, counterparty_outp, 1000, 100);
1401 assert_eq!(package.package_weight(&Script::new()), weight_sans_output + weight_received_htlc(channel_type_features) as usize);
1406 for channel_type_features in [ChannelTypeFeatures::only_static_remote_key(), ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()].iter() {
1407 let counterparty_outp = dumb_counterparty_offered_output!(secp_ctx, 1_000_000, channel_type_features.clone());
1408 let package = PackageTemplate::build_package(txid, 0, counterparty_outp, 1000, 100);
1409 assert_eq!(package.package_weight(&Script::new()), weight_sans_output + weight_offered_htlc(channel_type_features) as usize);