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.
15 use bitcoin::{Sequence, Witness};
16 use bitcoin::blockdata::constants::WITNESS_SCALE_FACTOR;
17 use bitcoin::blockdata::locktime::absolute::LockTime;
18 use bitcoin::blockdata::transaction::{TxOut,TxIn, Transaction};
19 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
20 use bitcoin::blockdata::script::{Script, ScriptBuf};
21 use bitcoin::hash_types::Txid;
22 use bitcoin::secp256k1::{SecretKey,PublicKey};
23 use bitcoin::sighash::EcdsaSighashType;
25 use crate::ln::PaymentPreimage;
26 use crate::ln::chan_utils::{self, TxCreationKeys, HTLCOutputInCommitment};
27 use crate::ln::features::ChannelTypeFeatures;
28 use crate::ln::channel_keys::{DelayedPaymentBasepoint, HtlcBasepoint};
29 use crate::ln::msgs::DecodeError;
30 use crate::chain::chaininterface::{FeeEstimator, ConfirmationTarget, MIN_RELAY_FEE_SAT_PER_1000_WEIGHT, compute_feerate_sat_per_1000_weight, FEERATE_FLOOR_SATS_PER_KW};
31 use crate::sign::ecdsa::WriteableEcdsaChannelSigner;
32 use crate::chain::onchaintx::{ExternalHTLCClaim, OnchainTxHandler};
33 use crate::util::logger::Logger;
34 use crate::util::ser::{Readable, Writer, Writeable, RequiredWrapper};
37 use crate::prelude::*;
39 use core::convert::TryInto;
43 use super::chaininterface::LowerBoundedFeeEstimator;
45 const MAX_ALLOC_SIZE: usize = 64*1024;
48 pub(crate) fn weight_revoked_offered_htlc(channel_type_features: &ChannelTypeFeatures) -> u64 {
49 // number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
50 const WEIGHT_REVOKED_OFFERED_HTLC: u64 = 1 + 1 + 73 + 1 + 33 + 1 + 133;
51 const WEIGHT_REVOKED_OFFERED_HTLC_ANCHORS: u64 = WEIGHT_REVOKED_OFFERED_HTLC + 3; // + OP_1 + OP_CSV + OP_DROP
52 if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_REVOKED_OFFERED_HTLC_ANCHORS } else { WEIGHT_REVOKED_OFFERED_HTLC }
55 pub(crate) fn weight_revoked_received_htlc(channel_type_features: &ChannelTypeFeatures) -> u64 {
56 // number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
57 const WEIGHT_REVOKED_RECEIVED_HTLC: u64 = 1 + 1 + 73 + 1 + 33 + 1 + 139;
58 const WEIGHT_REVOKED_RECEIVED_HTLC_ANCHORS: u64 = WEIGHT_REVOKED_RECEIVED_HTLC + 3; // + OP_1 + OP_CSV + OP_DROP
59 if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_REVOKED_RECEIVED_HTLC_ANCHORS } else { WEIGHT_REVOKED_RECEIVED_HTLC }
62 pub(crate) fn weight_offered_htlc(channel_type_features: &ChannelTypeFeatures) -> u64 {
63 // number_of_witness_elements + sig_length + counterpartyhtlc_sig + preimage_length + preimage + witness_script_length + witness_script
64 const WEIGHT_OFFERED_HTLC: u64 = 1 + 1 + 73 + 1 + 32 + 1 + 133;
65 const WEIGHT_OFFERED_HTLC_ANCHORS: u64 = WEIGHT_OFFERED_HTLC + 3; // + OP_1 + OP_CSV + OP_DROP
66 if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_OFFERED_HTLC_ANCHORS } else { WEIGHT_OFFERED_HTLC }
69 pub(crate) fn weight_received_htlc(channel_type_features: &ChannelTypeFeatures) -> u64 {
70 // number_of_witness_elements + sig_length + counterpartyhtlc_sig + empty_vec_length + empty_vec + witness_script_length + witness_script
71 const WEIGHT_RECEIVED_HTLC: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 139;
72 const WEIGHT_RECEIVED_HTLC_ANCHORS: u64 = WEIGHT_RECEIVED_HTLC + 3; // + OP_1 + OP_CSV + OP_DROP
73 if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_RECEIVED_HTLC_ANCHORS } else { WEIGHT_RECEIVED_HTLC }
76 /// Verifies deserializable channel type features
77 pub(crate) fn verify_channel_type_features(channel_type_features: &Option<ChannelTypeFeatures>, additional_permitted_features: Option<&ChannelTypeFeatures>) -> Result<(), DecodeError> {
78 if let Some(features) = channel_type_features.as_ref() {
79 if features.requires_unknown_bits() {
80 return Err(DecodeError::UnknownRequiredFeature);
83 let mut supported_feature_set = ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies();
84 supported_feature_set.set_scid_privacy_required();
85 supported_feature_set.set_zero_conf_required();
87 // allow the passing of an additional necessary permitted flag
88 if let Some(additional_permitted_features) = additional_permitted_features {
89 supported_feature_set |= additional_permitted_features;
92 if !features.is_subset(&supported_feature_set) {
93 return Err(DecodeError::UnknownRequiredFeature);
100 // number_of_witness_elements + sig_length + revocation_sig + true_length + op_true + witness_script_length + witness_script
101 pub(crate) const WEIGHT_REVOKED_OUTPUT: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 77;
103 /// Height delay at which transactions are fee-bumped/rebroadcasted with a low priority.
104 const LOW_FREQUENCY_BUMP_INTERVAL: u32 = 15;
105 /// Height delay at which transactions are fee-bumped/rebroadcasted with a middle priority.
106 const MIDDLE_FREQUENCY_BUMP_INTERVAL: u32 = 3;
107 /// Height delay at which transactions are fee-bumped/rebroadcasted with a high priority.
108 const HIGH_FREQUENCY_BUMP_INTERVAL: u32 = 1;
110 /// A struct to describe a revoked output and corresponding information to generate a solving
111 /// witness spending a commitment `to_local` output or a second-stage HTLC transaction output.
113 /// CSV and pubkeys are used as part of a witnessScript redeeming a balance output, amount is used
114 /// as part of the signature hash and revocation secret to generate a satisfying witness.
115 #[derive(Clone, PartialEq, Eq)]
116 pub(crate) struct RevokedOutput {
117 per_commitment_point: PublicKey,
118 counterparty_delayed_payment_base_key: DelayedPaymentBasepoint,
119 counterparty_htlc_base_key: HtlcBasepoint,
120 per_commitment_key: SecretKey,
123 on_counterparty_tx_csv: u16,
124 is_counterparty_balance_on_anchors: Option<()>,
128 pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: DelayedPaymentBasepoint, counterparty_htlc_base_key: HtlcBasepoint, per_commitment_key: SecretKey, amount: u64, on_counterparty_tx_csv: u16, is_counterparty_balance_on_anchors: bool) -> Self {
130 per_commitment_point,
131 counterparty_delayed_payment_base_key,
132 counterparty_htlc_base_key,
134 weight: WEIGHT_REVOKED_OUTPUT,
136 on_counterparty_tx_csv,
137 is_counterparty_balance_on_anchors: if is_counterparty_balance_on_anchors { Some(()) } else { None }
142 impl_writeable_tlv_based!(RevokedOutput, {
143 (0, per_commitment_point, required),
144 (2, counterparty_delayed_payment_base_key, required),
145 (4, counterparty_htlc_base_key, required),
146 (6, per_commitment_key, required),
147 (8, weight, required),
148 (10, amount, required),
149 (12, on_counterparty_tx_csv, required),
150 (14, is_counterparty_balance_on_anchors, option)
153 /// A struct to describe a revoked offered output and corresponding information to generate a
156 /// HTLCOuputInCommitment (hash timelock, direction) and pubkeys are used to generate a suitable
159 /// CSV is used as part of a witnessScript redeeming a balance output, amount is used as part
160 /// of the signature hash and revocation secret to generate a satisfying witness.
161 #[derive(Clone, PartialEq, Eq)]
162 pub(crate) struct RevokedHTLCOutput {
163 per_commitment_point: PublicKey,
164 counterparty_delayed_payment_base_key: DelayedPaymentBasepoint,
165 counterparty_htlc_base_key: HtlcBasepoint,
166 per_commitment_key: SecretKey,
169 htlc: HTLCOutputInCommitment,
172 impl RevokedHTLCOutput {
173 pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: DelayedPaymentBasepoint, counterparty_htlc_base_key: HtlcBasepoint, per_commitment_key: SecretKey, amount: u64, htlc: HTLCOutputInCommitment, channel_type_features: &ChannelTypeFeatures) -> Self {
174 let weight = if htlc.offered { weight_revoked_offered_htlc(channel_type_features) } else { weight_revoked_received_htlc(channel_type_features) };
176 per_commitment_point,
177 counterparty_delayed_payment_base_key,
178 counterparty_htlc_base_key,
187 impl_writeable_tlv_based!(RevokedHTLCOutput, {
188 (0, per_commitment_point, required),
189 (2, counterparty_delayed_payment_base_key, required),
190 (4, counterparty_htlc_base_key, required),
191 (6, per_commitment_key, required),
192 (8, weight, required),
193 (10, amount, required),
194 (12, htlc, required),
197 /// A struct to describe a HTLC output on a counterparty commitment transaction.
199 /// HTLCOutputInCommitment (hash, timelock, directon) and pubkeys are used to generate a suitable
202 /// The preimage is used as part of the witness.
204 /// Note that on upgrades, some features of existing outputs may be missed.
205 #[derive(Clone, PartialEq, Eq)]
206 pub(crate) struct CounterpartyOfferedHTLCOutput {
207 per_commitment_point: PublicKey,
208 counterparty_delayed_payment_base_key: DelayedPaymentBasepoint,
209 counterparty_htlc_base_key: HtlcBasepoint,
210 preimage: PaymentPreimage,
211 htlc: HTLCOutputInCommitment,
212 channel_type_features: ChannelTypeFeatures,
215 impl CounterpartyOfferedHTLCOutput {
216 pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: DelayedPaymentBasepoint, counterparty_htlc_base_key: HtlcBasepoint, preimage: PaymentPreimage, htlc: HTLCOutputInCommitment, channel_type_features: ChannelTypeFeatures) -> Self {
217 CounterpartyOfferedHTLCOutput {
218 per_commitment_point,
219 counterparty_delayed_payment_base_key,
220 counterparty_htlc_base_key,
223 channel_type_features,
228 impl Writeable for CounterpartyOfferedHTLCOutput {
229 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
230 let legacy_deserialization_prevention_marker = chan_utils::legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
231 write_tlv_fields!(writer, {
232 (0, self.per_commitment_point, required),
233 (2, self.counterparty_delayed_payment_base_key, required),
234 (4, self.counterparty_htlc_base_key, required),
235 (6, self.preimage, required),
236 (8, self.htlc, required),
237 (10, legacy_deserialization_prevention_marker, option),
238 (11, self.channel_type_features, required),
244 impl Readable for CounterpartyOfferedHTLCOutput {
245 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
246 let mut per_commitment_point = RequiredWrapper(None);
247 let mut counterparty_delayed_payment_base_key = RequiredWrapper(None);
248 let mut counterparty_htlc_base_key = RequiredWrapper(None);
249 let mut preimage = RequiredWrapper(None);
250 let mut htlc = RequiredWrapper(None);
251 let mut _legacy_deserialization_prevention_marker: Option<()> = None;
252 let mut channel_type_features = None;
254 read_tlv_fields!(reader, {
255 (0, per_commitment_point, required),
256 (2, counterparty_delayed_payment_base_key, required),
257 (4, counterparty_htlc_base_key, required),
258 (6, preimage, required),
260 (10, _legacy_deserialization_prevention_marker, option),
261 (11, channel_type_features, option),
264 verify_channel_type_features(&channel_type_features, None)?;
267 per_commitment_point: per_commitment_point.0.unwrap(),
268 counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
269 counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
270 preimage: preimage.0.unwrap(),
271 htlc: htlc.0.unwrap(),
272 channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
277 /// A struct to describe a HTLC output on a counterparty commitment transaction.
279 /// HTLCOutputInCommitment (hash, timelock, directon) and pubkeys are used to generate a suitable
282 /// Note that on upgrades, some features of existing outputs may be missed.
283 #[derive(Clone, PartialEq, Eq)]
284 pub(crate) struct CounterpartyReceivedHTLCOutput {
285 per_commitment_point: PublicKey,
286 counterparty_delayed_payment_base_key: DelayedPaymentBasepoint,
287 counterparty_htlc_base_key: HtlcBasepoint,
288 htlc: HTLCOutputInCommitment,
289 channel_type_features: ChannelTypeFeatures,
292 impl CounterpartyReceivedHTLCOutput {
293 pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: DelayedPaymentBasepoint, counterparty_htlc_base_key: HtlcBasepoint, htlc: HTLCOutputInCommitment, channel_type_features: ChannelTypeFeatures) -> Self {
294 CounterpartyReceivedHTLCOutput {
295 per_commitment_point,
296 counterparty_delayed_payment_base_key,
297 counterparty_htlc_base_key,
299 channel_type_features
304 impl Writeable for CounterpartyReceivedHTLCOutput {
305 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
306 let legacy_deserialization_prevention_marker = chan_utils::legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
307 write_tlv_fields!(writer, {
308 (0, self.per_commitment_point, required),
309 (2, self.counterparty_delayed_payment_base_key, required),
310 (4, self.counterparty_htlc_base_key, required),
311 (6, self.htlc, required),
312 (8, legacy_deserialization_prevention_marker, option),
313 (9, self.channel_type_features, required),
319 impl Readable for CounterpartyReceivedHTLCOutput {
320 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
321 let mut per_commitment_point = RequiredWrapper(None);
322 let mut counterparty_delayed_payment_base_key = RequiredWrapper(None);
323 let mut counterparty_htlc_base_key = RequiredWrapper(None);
324 let mut htlc = RequiredWrapper(None);
325 let mut _legacy_deserialization_prevention_marker: Option<()> = None;
326 let mut channel_type_features = None;
328 read_tlv_fields!(reader, {
329 (0, per_commitment_point, required),
330 (2, counterparty_delayed_payment_base_key, required),
331 (4, counterparty_htlc_base_key, required),
333 (8, _legacy_deserialization_prevention_marker, option),
334 (9, channel_type_features, option),
337 verify_channel_type_features(&channel_type_features, None)?;
340 per_commitment_point: per_commitment_point.0.unwrap(),
341 counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
342 counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
343 htlc: htlc.0.unwrap(),
344 channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
349 /// A struct to describe a HTLC output on holder commitment transaction.
351 /// Either offered or received, the amount is always used as part of the bip143 sighash.
352 /// Preimage is only included as part of the witness in former case.
354 /// Note that on upgrades, some features of existing outputs may be missed.
355 #[derive(Clone, PartialEq, Eq)]
356 pub(crate) struct HolderHTLCOutput {
357 preimage: Option<PaymentPreimage>,
359 /// Defaults to 0 for HTLC-Success transactions, which have no expiry
361 channel_type_features: ChannelTypeFeatures,
364 impl HolderHTLCOutput {
365 pub(crate) fn build_offered(amount_msat: u64, cltv_expiry: u32, channel_type_features: ChannelTypeFeatures) -> Self {
370 channel_type_features,
374 pub(crate) fn build_accepted(preimage: PaymentPreimage, amount_msat: u64, channel_type_features: ChannelTypeFeatures) -> Self {
376 preimage: Some(preimage),
379 channel_type_features,
384 impl Writeable for HolderHTLCOutput {
385 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
386 let legacy_deserialization_prevention_marker = chan_utils::legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
387 write_tlv_fields!(writer, {
388 (0, self.amount_msat, required),
389 (2, self.cltv_expiry, required),
390 (4, self.preimage, option),
391 (6, legacy_deserialization_prevention_marker, option),
392 (7, self.channel_type_features, required),
398 impl Readable for HolderHTLCOutput {
399 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
400 let mut amount_msat = RequiredWrapper(None);
401 let mut cltv_expiry = RequiredWrapper(None);
402 let mut preimage = None;
403 let mut _legacy_deserialization_prevention_marker: Option<()> = None;
404 let mut channel_type_features = None;
406 read_tlv_fields!(reader, {
407 (0, amount_msat, required),
408 (2, cltv_expiry, required),
409 (4, preimage, option),
410 (6, _legacy_deserialization_prevention_marker, option),
411 (7, channel_type_features, option),
414 verify_channel_type_features(&channel_type_features, None)?;
417 amount_msat: amount_msat.0.unwrap(),
418 cltv_expiry: cltv_expiry.0.unwrap(),
420 channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
425 /// A struct to describe the channel output on the funding transaction.
427 /// witnessScript is used as part of the witness redeeming the funding utxo.
429 /// Note that on upgrades, some features of existing outputs may be missed.
430 #[derive(Clone, PartialEq, Eq)]
431 pub(crate) struct HolderFundingOutput {
432 funding_redeemscript: ScriptBuf,
433 pub(crate) funding_amount: Option<u64>,
434 channel_type_features: ChannelTypeFeatures,
438 impl HolderFundingOutput {
439 pub(crate) fn build(funding_redeemscript: ScriptBuf, funding_amount: u64, channel_type_features: ChannelTypeFeatures) -> Self {
440 HolderFundingOutput {
441 funding_redeemscript,
442 funding_amount: Some(funding_amount),
443 channel_type_features,
448 impl Writeable for HolderFundingOutput {
449 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
450 let legacy_deserialization_prevention_marker = chan_utils::legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
451 write_tlv_fields!(writer, {
452 (0, self.funding_redeemscript, required),
453 (1, self.channel_type_features, required),
454 (2, legacy_deserialization_prevention_marker, option),
455 (3, self.funding_amount, option),
461 impl Readable for HolderFundingOutput {
462 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
463 let mut funding_redeemscript = RequiredWrapper(None);
464 let mut _legacy_deserialization_prevention_marker: Option<()> = None;
465 let mut channel_type_features = None;
466 let mut funding_amount = None;
468 read_tlv_fields!(reader, {
469 (0, funding_redeemscript, required),
470 (1, channel_type_features, option),
471 (2, _legacy_deserialization_prevention_marker, option),
472 (3, funding_amount, option)
475 verify_channel_type_features(&channel_type_features, None)?;
478 funding_redeemscript: funding_redeemscript.0.unwrap(),
479 channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key()),
485 /// A wrapper encapsulating all in-protocol differing outputs types.
487 /// The generic API offers access to an outputs common attributes or allow transformation such as
488 /// finalizing an input claiming the output.
489 #[derive(Clone, PartialEq, Eq)]
490 pub(crate) enum PackageSolvingData {
491 RevokedOutput(RevokedOutput),
492 RevokedHTLCOutput(RevokedHTLCOutput),
493 CounterpartyOfferedHTLCOutput(CounterpartyOfferedHTLCOutput),
494 CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput),
495 HolderHTLCOutput(HolderHTLCOutput),
496 HolderFundingOutput(HolderFundingOutput),
499 impl PackageSolvingData {
500 fn amount(&self) -> u64 {
501 let amt = match self {
502 PackageSolvingData::RevokedOutput(ref outp) => outp.amount,
503 PackageSolvingData::RevokedHTLCOutput(ref outp) => outp.amount,
504 PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => outp.htlc.amount_msat / 1000,
505 PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => outp.htlc.amount_msat / 1000,
506 PackageSolvingData::HolderHTLCOutput(ref outp) => {
507 debug_assert!(outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
508 outp.amount_msat / 1000
510 PackageSolvingData::HolderFundingOutput(ref outp) => {
511 debug_assert!(outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
512 outp.funding_amount.unwrap()
517 fn weight(&self) -> usize {
519 PackageSolvingData::RevokedOutput(ref outp) => outp.weight as usize,
520 PackageSolvingData::RevokedHTLCOutput(ref outp) => outp.weight as usize,
521 PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => weight_offered_htlc(&outp.channel_type_features) as usize,
522 PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => weight_received_htlc(&outp.channel_type_features) as usize,
523 PackageSolvingData::HolderHTLCOutput(ref outp) => {
524 debug_assert!(outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
525 if outp.preimage.is_none() {
526 weight_offered_htlc(&outp.channel_type_features) as usize
528 weight_received_htlc(&outp.channel_type_features) as usize
531 // Since HolderFundingOutput maps to an untractable package that is already signed, its
532 // weight can be determined from the transaction itself.
533 PackageSolvingData::HolderFundingOutput(..) => unreachable!(),
536 fn is_compatible(&self, input: &PackageSolvingData) -> bool {
538 PackageSolvingData::RevokedOutput(..) => {
540 PackageSolvingData::RevokedHTLCOutput(..) => { true },
541 PackageSolvingData::RevokedOutput(..) => { true },
545 PackageSolvingData::RevokedHTLCOutput(..) => {
547 PackageSolvingData::RevokedOutput(..) => { true },
548 PackageSolvingData::RevokedHTLCOutput(..) => { true },
552 _ => { mem::discriminant(self) == mem::discriminant(&input) }
555 fn as_tx_input(&self, previous_output: BitcoinOutPoint) -> TxIn {
556 let sequence = match self {
557 PackageSolvingData::RevokedOutput(_) => Sequence::ENABLE_RBF_NO_LOCKTIME,
558 PackageSolvingData::RevokedHTLCOutput(_) => Sequence::ENABLE_RBF_NO_LOCKTIME,
559 PackageSolvingData::CounterpartyOfferedHTLCOutput(outp) => if outp.channel_type_features.supports_anchors_zero_fee_htlc_tx() {
560 Sequence::from_consensus(1)
562 Sequence::ENABLE_RBF_NO_LOCKTIME
564 PackageSolvingData::CounterpartyReceivedHTLCOutput(outp) => if outp.channel_type_features.supports_anchors_zero_fee_htlc_tx() {
565 Sequence::from_consensus(1)
567 Sequence::ENABLE_RBF_NO_LOCKTIME
570 debug_assert!(false, "This should not be reachable by 'untractable' or 'malleable with external funding' packages");
571 Sequence::ENABLE_RBF_NO_LOCKTIME
576 script_sig: ScriptBuf::new(),
578 witness: Witness::new(),
581 fn finalize_input<Signer: WriteableEcdsaChannelSigner>(&self, bumped_tx: &mut Transaction, i: usize, onchain_handler: &mut OnchainTxHandler<Signer>) -> bool {
583 PackageSolvingData::RevokedOutput(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_revokeable_redeemscript(&chan_keys.revocation_key, outp.on_counterparty_tx_csv, &chan_keys.broadcaster_delayed_payment_key);
586 //TODO: should we panic on signer failure ?
587 if let Ok(sig) = onchain_handler.signer.sign_justice_revoked_output(&bumped_tx, i, outp.amount, &outp.per_commitment_key, &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(vec!(1));
592 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
593 } else { return false; }
595 PackageSolvingData::RevokedHTLCOutput(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);
598 //TODO: should we panic on signer failure ?
599 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) {
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 bumped_tx.input[i].witness.push(chan_keys.revocation_key.to_public_key().serialize().to_vec());
604 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
605 } else { return false; }
607 PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => {
608 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);
609 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);
611 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) {
612 let mut ser_sig = sig.serialize_der().to_vec();
613 ser_sig.push(EcdsaSighashType::All as u8);
614 bumped_tx.input[i].witness.push(ser_sig);
615 bumped_tx.input[i].witness.push(outp.preimage.0.to_vec());
616 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
619 PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => {
620 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);
621 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);
623 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) {
624 let mut ser_sig = sig.serialize_der().to_vec();
625 ser_sig.push(EcdsaSighashType::All as u8);
626 bumped_tx.input[i].witness.push(ser_sig);
627 // Due to BIP146 (MINIMALIF) this must be a zero-length element to relay.
628 bumped_tx.input[i].witness.push(vec![]);
629 bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
632 _ => { panic!("API Error!"); }
636 fn get_finalized_tx<Signer: WriteableEcdsaChannelSigner>(&self, outpoint: &BitcoinOutPoint, onchain_handler: &mut OnchainTxHandler<Signer>) -> Option<Transaction> {
638 PackageSolvingData::HolderHTLCOutput(ref outp) => {
639 debug_assert!(!outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
640 return onchain_handler.get_fully_signed_htlc_tx(outpoint, &outp.preimage);
642 PackageSolvingData::HolderFundingOutput(ref outp) => {
643 return Some(onchain_handler.get_fully_signed_holder_tx(&outp.funding_redeemscript));
645 _ => { panic!("API Error!"); }
648 fn absolute_tx_timelock(&self, current_height: u32) -> u32 {
649 // We use `current_height` as our default locktime to discourage fee sniping and because
650 // transactions with it always propagate.
651 let absolute_timelock = match self {
652 PackageSolvingData::RevokedOutput(_) => current_height,
653 PackageSolvingData::RevokedHTLCOutput(_) => current_height,
654 PackageSolvingData::CounterpartyOfferedHTLCOutput(_) => current_height,
655 PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => cmp::max(outp.htlc.cltv_expiry, current_height),
656 // HTLC timeout/success transactions rely on a fixed timelock due to the counterparty's
658 PackageSolvingData::HolderHTLCOutput(ref outp) => {
659 if outp.preimage.is_some() {
660 debug_assert_eq!(outp.cltv_expiry, 0);
664 PackageSolvingData::HolderFundingOutput(_) => current_height,
669 fn map_output_type_flags(&self) -> (PackageMalleability, bool) {
670 // Post-anchor, aggregation of outputs of different types is unsafe. See https://github.com/lightning/bolts/pull/803.
671 let (malleability, aggregable) = match self {
672 PackageSolvingData::RevokedOutput(RevokedOutput { is_counterparty_balance_on_anchors: Some(()), .. }) => { (PackageMalleability::Malleable, false) },
673 PackageSolvingData::RevokedOutput(RevokedOutput { is_counterparty_balance_on_anchors: None, .. }) => { (PackageMalleability::Malleable, true) },
674 PackageSolvingData::RevokedHTLCOutput(..) => { (PackageMalleability::Malleable, true) },
675 PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { (PackageMalleability::Malleable, true) },
676 PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { (PackageMalleability::Malleable, false) },
677 PackageSolvingData::HolderHTLCOutput(ref outp) => if outp.channel_type_features.supports_anchors_zero_fee_htlc_tx() {
678 (PackageMalleability::Malleable, outp.preimage.is_some())
680 (PackageMalleability::Untractable, false)
682 PackageSolvingData::HolderFundingOutput(..) => { (PackageMalleability::Untractable, false) },
684 (malleability, aggregable)
688 impl_writeable_tlv_based_enum!(PackageSolvingData, ;
690 (1, RevokedHTLCOutput),
691 (2, CounterpartyOfferedHTLCOutput),
692 (3, CounterpartyReceivedHTLCOutput),
693 (4, HolderHTLCOutput),
694 (5, HolderFundingOutput),
697 /// A malleable package might be aggregated with other packages to save on fees.
698 /// A untractable package has been counter-signed and aggregable will break cached counterparty signatures.
699 #[derive(Clone, PartialEq, Eq)]
700 pub(crate) enum PackageMalleability {
705 /// A structure to describe a package content that is generated by ChannelMonitor and
706 /// used by OnchainTxHandler to generate and broadcast transactions settling onchain claims.
708 /// A package is defined as one or more transactions claiming onchain outputs in reaction
709 /// to confirmation of a channel transaction. Those packages might be aggregated to save on
710 /// fees, if satisfaction of outputs's witnessScript let's us do so.
712 /// As packages are time-sensitive, we fee-bump and rebroadcast them at scheduled intervals.
713 /// Failing to confirm a package translate as a loss of funds for the user.
714 #[derive(Clone, PartialEq, Eq)]
715 pub struct PackageTemplate {
716 // List of onchain outputs and solving data to generate satisfying witnesses.
717 inputs: Vec<(BitcoinOutPoint, PackageSolvingData)>,
718 // Packages are deemed as malleable if we have local knwoledge of at least one set of
719 // private keys yielding a satisfying witnesses. Malleability implies that we can aggregate
720 // packages among them to save on fees or rely on RBF to bump their feerates.
721 // Untractable packages have been counter-signed and thus imply that we can't aggregate
722 // them without breaking signatures. Fee-bumping strategy will also rely on CPFP.
723 malleability: PackageMalleability,
724 // Block height after which the earlier-output belonging to this package is mature for a
725 // competing claim by the counterparty. As our chain tip becomes nearer from the timelock,
726 // the fee-bumping frequency will increase. See `OnchainTxHandler::get_height_timer`.
727 soonest_conf_deadline: u32,
728 // Determines if this package can be aggregated.
729 // Timelocked outputs belonging to the same transaction might have differing
730 // satisfying heights. Picking up the later height among the output set would be a valid
731 // aggregable strategy but it comes with at least 2 trade-offs :
732 // * earlier-output fund are going to take longer to come back
733 // * CLTV delta backing up a corresponding HTLC on an upstream channel could be swallowed
734 // by the requirement of the later-output part of the set
735 // For now, we mark such timelocked outputs as non-aggregable, though we might introduce
736 // smarter aggregable strategy in the future.
738 // Cache of package feerate committed at previous (re)broadcast. If bumping resources
739 // (either claimed output value or external utxo), it will keep increasing until holder
740 // or counterparty successful claim.
741 feerate_previous: u64,
742 // Cache of next height at which fee-bumping and rebroadcast will be attempted. In
743 // the future, we might abstract it to an observed mempool fluctuation.
745 // Confirmation height of the claimed outputs set transaction. In case of reorg reaching
746 // it, we wipe out and forget the package.
747 height_original: u32,
750 impl PackageTemplate {
751 pub(crate) fn is_malleable(&self) -> bool {
752 self.malleability == PackageMalleability::Malleable
754 pub(crate) fn timelock(&self) -> u32 {
755 self.soonest_conf_deadline
757 pub(crate) fn aggregable(&self) -> bool {
760 pub(crate) fn previous_feerate(&self) -> u64 {
761 self.feerate_previous
763 pub(crate) fn set_feerate(&mut self, new_feerate: u64) {
764 self.feerate_previous = new_feerate;
766 pub(crate) fn timer(&self) -> u32 {
769 pub(crate) fn set_timer(&mut self, new_timer: u32) {
770 self.height_timer = new_timer;
772 pub(crate) fn outpoints(&self) -> Vec<&BitcoinOutPoint> {
773 self.inputs.iter().map(|(o, _)| o).collect()
775 pub(crate) fn inputs(&self) -> impl ExactSizeIterator<Item = &PackageSolvingData> {
776 self.inputs.iter().map(|(_, i)| i)
778 pub(crate) fn split_package(&mut self, split_outp: &BitcoinOutPoint) -> Option<PackageTemplate> {
779 match self.malleability {
780 PackageMalleability::Malleable => {
781 let mut split_package = None;
782 let timelock = self.soonest_conf_deadline;
783 let aggregable = self.aggregable;
784 let feerate_previous = self.feerate_previous;
785 let height_timer = self.height_timer;
786 let height_original = self.height_original;
787 self.inputs.retain(|outp| {
788 if *split_outp == outp.0 {
789 split_package = Some(PackageTemplate {
790 inputs: vec![(outp.0, outp.1.clone())],
791 malleability: PackageMalleability::Malleable,
792 soonest_conf_deadline: timelock,
802 return split_package;
805 // Note, we may try to split on remote transaction for
806 // which we don't have a competing one (HTLC-Success before
807 // timelock expiration). This explain we don't panic!
808 // We should refactor OnchainTxHandler::block_connected to
809 // only test equality on competing claims.
814 pub(crate) fn merge_package(&mut self, mut merge_from: PackageTemplate) {
815 assert_eq!(self.height_original, merge_from.height_original);
816 if self.malleability == PackageMalleability::Untractable || merge_from.malleability == PackageMalleability::Untractable {
817 panic!("Merging template on untractable packages");
819 if !self.aggregable || !merge_from.aggregable {
820 panic!("Merging non aggregatable packages");
822 if let Some((_, lead_input)) = self.inputs.first() {
823 for (_, v) in merge_from.inputs.iter() {
824 if !lead_input.is_compatible(v) { panic!("Merging outputs from differing types !"); }
826 } else { panic!("Merging template on an empty package"); }
827 for (k, v) in merge_from.inputs.drain(..) {
828 self.inputs.push((k, v));
830 //TODO: verify coverage and sanity?
831 if self.soonest_conf_deadline > merge_from.soonest_conf_deadline {
832 self.soonest_conf_deadline = merge_from.soonest_conf_deadline;
834 if self.feerate_previous > merge_from.feerate_previous {
835 self.feerate_previous = merge_from.feerate_previous;
837 self.height_timer = cmp::min(self.height_timer, merge_from.height_timer);
839 /// Gets the amount of all outptus being spent by this package, only valid for malleable
841 pub(crate) fn package_amount(&self) -> u64 {
843 for (_, outp) in self.inputs.iter() {
844 amounts += outp.amount();
848 pub(crate) fn package_locktime(&self, current_height: u32) -> u32 {
849 let locktime = self.inputs.iter().map(|(_, outp)| outp.absolute_tx_timelock(current_height))
850 .max().expect("There must always be at least one output to spend in a PackageTemplate");
852 // If we ever try to aggregate a `HolderHTLCOutput`s with another output type, we'll likely
853 // end up with an incorrect transaction locktime since the counterparty has included it in
854 // its HTLC signature. This should never happen unless we decide to aggregate outputs across
855 // different channel commitments.
856 #[cfg(debug_assertions)] {
857 if self.inputs.iter().any(|(_, outp)|
858 if let PackageSolvingData::HolderHTLCOutput(outp) = outp {
859 outp.preimage.is_some()
864 debug_assert_eq!(locktime, 0);
866 for timeout_htlc_expiry in self.inputs.iter().filter_map(|(_, outp)|
867 if let PackageSolvingData::HolderHTLCOutput(outp) = outp {
868 if outp.preimage.is_none() {
869 Some(outp.cltv_expiry)
873 debug_assert_eq!(locktime, timeout_htlc_expiry);
879 pub(crate) fn package_weight(&self, destination_script: &Script) -> u64 {
880 let mut inputs_weight = 0;
881 let mut witnesses_weight = 2; // count segwit flags
882 for (_, outp) in self.inputs.iter() {
883 // previous_out_point: 36 bytes ; var_int: 1 byte ; sequence: 4 bytes
884 inputs_weight += 41 * WITNESS_SCALE_FACTOR;
885 witnesses_weight += outp.weight();
887 // version: 4 bytes ; count_tx_in: 1 byte ; count_tx_out: 1 byte ; lock_time: 4 bytes
888 let transaction_weight = 10 * WITNESS_SCALE_FACTOR;
889 // value: 8 bytes ; var_int: 1 byte ; pk_script: `destination_script.len()`
890 let output_weight = (8 + 1 + destination_script.len()) * WITNESS_SCALE_FACTOR;
891 (inputs_weight + witnesses_weight + transaction_weight + output_weight) as u64
893 pub(crate) fn construct_malleable_package_with_external_funding<Signer: WriteableEcdsaChannelSigner>(
894 &self, onchain_handler: &mut OnchainTxHandler<Signer>,
895 ) -> Option<Vec<ExternalHTLCClaim>> {
896 debug_assert!(self.requires_external_funding());
897 let mut htlcs: Option<Vec<ExternalHTLCClaim>> = None;
898 for (previous_output, input) in &self.inputs {
900 PackageSolvingData::HolderHTLCOutput(ref outp) => {
901 debug_assert!(outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
902 onchain_handler.generate_external_htlc_claim(&previous_output, &outp.preimage).map(|htlc| {
903 htlcs.get_or_insert_with(|| Vec::with_capacity(self.inputs.len())).push(htlc);
906 _ => debug_assert!(false, "Expected HolderHTLCOutputs to not be aggregated with other input types"),
911 pub(crate) fn finalize_malleable_package<L: Logger, Signer: WriteableEcdsaChannelSigner>(
912 &self, current_height: u32, onchain_handler: &mut OnchainTxHandler<Signer>, value: u64,
913 destination_script: ScriptBuf, logger: &L
914 ) -> Option<Transaction> {
915 debug_assert!(self.is_malleable());
916 let mut bumped_tx = Transaction {
918 lock_time: LockTime::from_consensus(self.package_locktime(current_height)),
921 script_pubkey: destination_script,
925 for (outpoint, outp) in self.inputs.iter() {
926 bumped_tx.input.push(outp.as_tx_input(*outpoint));
928 for (i, (outpoint, out)) in self.inputs.iter().enumerate() {
929 log_debug!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout);
930 if !out.finalize_input(&mut bumped_tx, i, onchain_handler) { return None; }
932 log_debug!(logger, "Finalized transaction {} ready to broadcast", bumped_tx.txid());
935 pub(crate) fn finalize_untractable_package<L: Logger, Signer: WriteableEcdsaChannelSigner>(
936 &self, onchain_handler: &mut OnchainTxHandler<Signer>, logger: &L,
937 ) -> Option<Transaction> {
938 debug_assert!(!self.is_malleable());
939 if let Some((outpoint, outp)) = self.inputs.first() {
940 if let Some(final_tx) = outp.get_finalized_tx(outpoint, onchain_handler) {
941 log_debug!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout);
942 log_debug!(logger, "Finalized transaction {} ready to broadcast", final_tx.txid());
943 return Some(final_tx);
946 } else { panic!("API Error: Package must not be inputs empty"); }
948 /// In LN, output claimed are time-sensitive, which means we have to spend them before reaching some timelock expiration. At in-channel
949 /// 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
950 /// height that once reached we should generate a new bumped "version" of the claim tx to be sure that we safely claim outputs before
951 /// that our counterparty can do so. If timelock expires soon, height timer is going to be scaled down in consequence to increase
952 /// frequency of the bump and so increase our bets of success.
953 pub(crate) fn get_height_timer(&self, current_height: u32) -> u32 {
954 if self.soonest_conf_deadline <= current_height + MIDDLE_FREQUENCY_BUMP_INTERVAL {
955 return current_height + HIGH_FREQUENCY_BUMP_INTERVAL
956 } else if self.soonest_conf_deadline - current_height <= LOW_FREQUENCY_BUMP_INTERVAL {
957 return current_height + MIDDLE_FREQUENCY_BUMP_INTERVAL
959 current_height + LOW_FREQUENCY_BUMP_INTERVAL
962 /// Returns value in satoshis to be included as package outgoing output amount and feerate
963 /// which was used to generate the value. Will not return less than `dust_limit_sats` for the
965 pub(crate) fn compute_package_output<F: Deref, L: Logger>(
966 &self, predicted_weight: u64, dust_limit_sats: u64, force_feerate_bump: bool,
967 fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L,
968 ) -> Option<(u64, u64)>
969 where F::Target: FeeEstimator,
971 debug_assert!(self.malleability == PackageMalleability::Malleable, "The package output is fixed for non-malleable packages");
972 let input_amounts = self.package_amount();
973 assert!(dust_limit_sats as i64 > 0, "Output script must be broadcastable/have a 'real' dust limit.");
974 // If old feerate is 0, first iteration of this claim, use normal fee calculation
975 if self.feerate_previous != 0 {
976 if let Some((new_fee, feerate)) = feerate_bump(
977 predicted_weight, input_amounts, self.feerate_previous, force_feerate_bump,
978 fee_estimator, logger,
980 return Some((cmp::max(input_amounts as i64 - new_fee as i64, dust_limit_sats as i64) as u64, feerate));
983 if let Some((new_fee, feerate)) = compute_fee_from_spent_amounts(input_amounts, predicted_weight, fee_estimator, logger) {
984 return Some((cmp::max(input_amounts as i64 - new_fee as i64, dust_limit_sats as i64) as u64, feerate));
990 /// Computes a feerate based on the given confirmation target. If a previous feerate was used,
991 /// the new feerate is below it, and `force_feerate_bump` is set, we'll use a 25% increase of
992 /// the previous feerate instead of the new feerate.
993 pub(crate) fn compute_package_feerate<F: Deref>(
994 &self, fee_estimator: &LowerBoundedFeeEstimator<F>, conf_target: ConfirmationTarget,
995 force_feerate_bump: bool,
996 ) -> u32 where F::Target: FeeEstimator {
997 let feerate_estimate = fee_estimator.bounded_sat_per_1000_weight(conf_target);
998 if self.feerate_previous != 0 {
999 // Use the new fee estimate if it's higher than the one previously used.
1000 if feerate_estimate as u64 > self.feerate_previous {
1002 } else if !force_feerate_bump {
1003 self.feerate_previous.try_into().unwrap_or(u32::max_value())
1005 // Our fee estimate has decreased, but our transaction remains unconfirmed after
1006 // using our previous fee estimate. This may point to an unreliable fee estimator,
1007 // so we choose to bump our previous feerate by 25%, making sure we don't use a
1008 // lower feerate or overpay by a large margin by limiting it to 5x the new fee
1010 let previous_feerate = self.feerate_previous.try_into().unwrap_or(u32::max_value());
1011 let mut new_feerate = previous_feerate.saturating_add(previous_feerate / 4);
1012 if new_feerate > feerate_estimate * 5 {
1013 new_feerate = cmp::max(feerate_estimate * 5, previous_feerate);
1022 /// Determines whether a package contains an input which must have additional external inputs
1023 /// attached to help the spending transaction reach confirmation.
1024 pub(crate) fn requires_external_funding(&self) -> bool {
1025 self.inputs.iter().find(|input| match input.1 {
1026 PackageSolvingData::HolderFundingOutput(ref outp) => outp.channel_type_features.supports_anchors_zero_fee_htlc_tx(),
1027 PackageSolvingData::HolderHTLCOutput(ref outp) => outp.channel_type_features.supports_anchors_zero_fee_htlc_tx(),
1032 pub (crate) fn build_package(txid: Txid, vout: u32, input_solving_data: PackageSolvingData, soonest_conf_deadline: u32, height_original: u32) -> Self {
1033 let (malleability, aggregable) = PackageSolvingData::map_output_type_flags(&input_solving_data);
1034 let mut inputs = Vec::with_capacity(1);
1035 inputs.push((BitcoinOutPoint { txid, vout }, input_solving_data));
1039 soonest_conf_deadline,
1041 feerate_previous: 0,
1042 height_timer: height_original,
1048 impl Writeable for PackageTemplate {
1049 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1050 writer.write_all(&(self.inputs.len() as u64).to_be_bytes())?;
1051 for (ref outpoint, ref rev_outp) in self.inputs.iter() {
1052 outpoint.write(writer)?;
1053 rev_outp.write(writer)?;
1055 write_tlv_fields!(writer, {
1056 (0, self.soonest_conf_deadline, required),
1057 (2, self.feerate_previous, required),
1058 (4, self.height_original, required),
1059 (6, self.height_timer, required)
1065 impl Readable for PackageTemplate {
1066 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
1067 let inputs_count = <u64 as Readable>::read(reader)?;
1068 let mut inputs: Vec<(BitcoinOutPoint, PackageSolvingData)> = Vec::with_capacity(cmp::min(inputs_count as usize, MAX_ALLOC_SIZE / 128));
1069 for _ in 0..inputs_count {
1070 let outpoint = Readable::read(reader)?;
1071 let rev_outp = Readable::read(reader)?;
1072 inputs.push((outpoint, rev_outp));
1074 let (malleability, aggregable) = if let Some((_, lead_input)) = inputs.first() {
1075 PackageSolvingData::map_output_type_flags(&lead_input)
1076 } else { return Err(DecodeError::InvalidValue); };
1077 let mut soonest_conf_deadline = 0;
1078 let mut feerate_previous = 0;
1079 let mut height_timer = None;
1080 let mut height_original = 0;
1081 read_tlv_fields!(reader, {
1082 (0, soonest_conf_deadline, required),
1083 (2, feerate_previous, required),
1084 (4, height_original, required),
1085 (6, height_timer, option),
1087 if height_timer.is_none() {
1088 height_timer = Some(height_original);
1090 Ok(PackageTemplate {
1093 soonest_conf_deadline,
1096 height_timer: height_timer.unwrap(),
1102 /// Attempt to propose a bumping fee for a transaction from its spent output's values and predicted
1103 /// weight. We first try our [`OnChainSweep`] feerate, if it's not enough we try to sweep half of
1104 /// the input amounts.
1106 /// If the proposed fee is less than the available spent output's values, we return the proposed
1107 /// fee and the corresponding updated feerate. If fee is under [`FEERATE_FLOOR_SATS_PER_KW`], we
1110 /// [`OnChainSweep`]: crate::chain::chaininterface::ConfirmationTarget::OnChainSweep
1111 /// [`FEERATE_FLOOR_SATS_PER_KW`]: crate::chain::chaininterface::MIN_RELAY_FEE_SAT_PER_1000_WEIGHT
1112 fn compute_fee_from_spent_amounts<F: Deref, L: Logger>(input_amounts: u64, predicted_weight: u64, fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L) -> Option<(u64, u64)>
1113 where F::Target: FeeEstimator,
1115 let sweep_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::OnChainSweep);
1116 let fee_rate = cmp::min(sweep_feerate, compute_feerate_sat_per_1000_weight(input_amounts / 2, predicted_weight));
1117 let fee = fee_rate as u64 * (predicted_weight) / 1000;
1119 // if the fee rate is below the floor, we don't sweep
1120 if fee_rate < FEERATE_FLOOR_SATS_PER_KW {
1121 log_error!(logger, "Failed to generate an on-chain tx with fee ({} sat/kw) was less than the floor ({} sat/kw)",
1122 fee_rate, FEERATE_FLOOR_SATS_PER_KW);
1125 Some((fee, fee_rate as u64))
1129 /// Attempt to propose a bumping fee for a transaction from its spent output's values and predicted
1130 /// weight. If feerates proposed by the fee-estimator have been increasing since last fee-bumping
1131 /// attempt, use them. If `force_feerate_bump` is set, we bump the feerate by 25% of the previous
1132 /// feerate, or just use the previous feerate otherwise. If a feerate bump did happen, we also
1133 /// verify that those bumping heuristics respect BIP125 rules 3) and 4) and if required adjust the
1134 /// new fee to meet the RBF policy requirement.
1135 fn feerate_bump<F: Deref, L: Logger>(
1136 predicted_weight: u64, input_amounts: u64, previous_feerate: u64, force_feerate_bump: bool,
1137 fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L,
1138 ) -> Option<(u64, u64)>
1140 F::Target: FeeEstimator,
1142 // If old feerate inferior to actual one given back by Fee Estimator, use it to compute new fee...
1143 let (new_fee, new_feerate) = if let Some((new_fee, new_feerate)) = compute_fee_from_spent_amounts(input_amounts, predicted_weight, fee_estimator, logger) {
1144 if new_feerate > previous_feerate {
1145 (new_fee, new_feerate)
1146 } else if !force_feerate_bump {
1147 let previous_fee = previous_feerate * predicted_weight / 1000;
1148 (previous_fee, previous_feerate)
1150 // ...else just increase the previous feerate by 25% (because that's a nice number)
1151 let bumped_feerate = previous_feerate + (previous_feerate / 4);
1152 let bumped_fee = bumped_feerate * predicted_weight / 1000;
1153 if input_amounts <= bumped_fee {
1154 log_warn!(logger, "Can't 25% bump new claiming tx, amount {} is too small", input_amounts);
1157 (bumped_fee, bumped_feerate)
1160 log_warn!(logger, "Can't new-estimation bump new claiming tx, amount {} is too small", input_amounts);
1164 // Our feerates should never decrease. If it hasn't changed though, we just need to
1165 // rebroadcast/re-sign the previous claim.
1166 debug_assert!(new_feerate >= previous_feerate);
1167 if new_feerate == previous_feerate {
1168 return Some((new_fee, new_feerate));
1171 let previous_fee = previous_feerate * predicted_weight / 1000;
1172 let min_relay_fee = MIN_RELAY_FEE_SAT_PER_1000_WEIGHT * predicted_weight / 1000;
1173 // BIP 125 Opt-in Full Replace-by-Fee Signaling
1174 // * 3. The replacement transaction pays an absolute fee of at least the sum paid by the original transactions.
1175 // * 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.
1176 let new_fee = if new_fee < previous_fee + min_relay_fee {
1177 new_fee + previous_fee + min_relay_fee - new_fee
1181 Some((new_fee, new_fee * 1000 / predicted_weight))
1186 use crate::chain::package::{CounterpartyOfferedHTLCOutput, CounterpartyReceivedHTLCOutput, HolderHTLCOutput, PackageTemplate, PackageSolvingData, RevokedOutput, WEIGHT_REVOKED_OUTPUT, weight_offered_htlc, weight_received_htlc};
1187 use crate::chain::Txid;
1188 use crate::ln::chan_utils::HTLCOutputInCommitment;
1189 use crate::ln::{PaymentPreimage, PaymentHash};
1190 use crate::ln::channel_keys::{DelayedPaymentBasepoint, HtlcBasepoint};
1192 use bitcoin::blockdata::constants::WITNESS_SCALE_FACTOR;
1193 use bitcoin::blockdata::script::ScriptBuf;
1194 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
1196 use bitcoin::hashes::hex::FromHex;
1198 use bitcoin::secp256k1::{PublicKey,SecretKey};
1199 use bitcoin::secp256k1::Secp256k1;
1200 use crate::ln::features::ChannelTypeFeatures;
1202 use std::str::FromStr;
1204 macro_rules! dumb_revk_output {
1205 ($secp_ctx: expr, $is_counterparty_balance_on_anchors: expr) => {
1207 let dumb_scalar = SecretKey::from_slice(&<Vec<u8>>::from_hex("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
1208 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
1209 PackageSolvingData::RevokedOutput(RevokedOutput::build(dumb_point, DelayedPaymentBasepoint::from(dumb_point), HtlcBasepoint::from(dumb_point), dumb_scalar, 0, 0, $is_counterparty_balance_on_anchors))
1214 macro_rules! dumb_counterparty_output {
1215 ($secp_ctx: expr, $amt: expr, $opt_anchors: expr) => {
1217 let dumb_scalar = SecretKey::from_slice(&<Vec<u8>>::from_hex("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
1218 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
1219 let hash = PaymentHash([1; 32]);
1220 let htlc = HTLCOutputInCommitment { offered: true, amount_msat: $amt, cltv_expiry: 0, payment_hash: hash, transaction_output_index: None };
1221 PackageSolvingData::CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput::build(dumb_point, DelayedPaymentBasepoint::from(dumb_point), HtlcBasepoint::from(dumb_point), htlc, $opt_anchors))
1226 macro_rules! dumb_counterparty_offered_output {
1227 ($secp_ctx: expr, $amt: expr, $opt_anchors: expr) => {
1229 let dumb_scalar = SecretKey::from_slice(&<Vec<u8>>::from_hex("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
1230 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
1231 let hash = PaymentHash([1; 32]);
1232 let preimage = PaymentPreimage([2;32]);
1233 let htlc = HTLCOutputInCommitment { offered: false, amount_msat: $amt, cltv_expiry: 1000, payment_hash: hash, transaction_output_index: None };
1234 PackageSolvingData::CounterpartyOfferedHTLCOutput(CounterpartyOfferedHTLCOutput::build(dumb_point, DelayedPaymentBasepoint::from(dumb_point), HtlcBasepoint::from(dumb_point), preimage, htlc, $opt_anchors))
1239 macro_rules! dumb_htlc_output {
1242 let preimage = PaymentPreimage([2;32]);
1243 PackageSolvingData::HolderHTLCOutput(HolderHTLCOutput::build_accepted(preimage, 0, ChannelTypeFeatures::only_static_remote_key()))
1250 fn test_package_differing_heights() {
1251 let txid = Txid::from_str("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1252 let secp_ctx = Secp256k1::new();
1253 let revk_outp = dumb_revk_output!(secp_ctx, false);
1255 let mut package_one_hundred = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, 100);
1256 let package_two_hundred = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, 200);
1257 package_one_hundred.merge_package(package_two_hundred);
1262 fn test_package_untractable_merge_to() {
1263 let txid = Txid::from_str("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1264 let secp_ctx = Secp256k1::new();
1265 let revk_outp = dumb_revk_output!(secp_ctx, false);
1266 let htlc_outp = dumb_htlc_output!();
1268 let mut untractable_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, 100);
1269 let malleable_package = PackageTemplate::build_package(txid, 1, htlc_outp.clone(), 1000, 100);
1270 untractable_package.merge_package(malleable_package);
1275 fn test_package_untractable_merge_from() {
1276 let txid = Txid::from_str("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1277 let secp_ctx = Secp256k1::new();
1278 let htlc_outp = dumb_htlc_output!();
1279 let revk_outp = dumb_revk_output!(secp_ctx, false);
1281 let mut malleable_package = PackageTemplate::build_package(txid, 0, htlc_outp.clone(), 1000, 100);
1282 let untractable_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, 100);
1283 malleable_package.merge_package(untractable_package);
1288 fn test_package_noaggregation_to() {
1289 let txid = Txid::from_str("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1290 let secp_ctx = Secp256k1::new();
1291 let revk_outp = dumb_revk_output!(secp_ctx, false);
1292 let revk_outp_counterparty_balance = dumb_revk_output!(secp_ctx, true);
1294 let mut noaggregation_package = PackageTemplate::build_package(txid, 0, revk_outp_counterparty_balance.clone(), 1000, 100);
1295 let aggregation_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, 100);
1296 noaggregation_package.merge_package(aggregation_package);
1301 fn test_package_noaggregation_from() {
1302 let txid = Txid::from_str("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1303 let secp_ctx = Secp256k1::new();
1304 let revk_outp = dumb_revk_output!(secp_ctx, false);
1305 let revk_outp_counterparty_balance = dumb_revk_output!(secp_ctx, true);
1307 let mut aggregation_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, 100);
1308 let noaggregation_package = PackageTemplate::build_package(txid, 1, revk_outp_counterparty_balance.clone(), 1000, 100);
1309 aggregation_package.merge_package(noaggregation_package);
1314 fn test_package_empty() {
1315 let txid = Txid::from_str("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1316 let secp_ctx = Secp256k1::new();
1317 let revk_outp = dumb_revk_output!(secp_ctx, false);
1319 let mut empty_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, 100);
1320 empty_package.inputs = vec![];
1321 let package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, 100);
1322 empty_package.merge_package(package);
1327 fn test_package_differing_categories() {
1328 let txid = Txid::from_str("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1329 let secp_ctx = Secp256k1::new();
1330 let revk_outp = dumb_revk_output!(secp_ctx, false);
1331 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 0, ChannelTypeFeatures::only_static_remote_key());
1333 let mut revoked_package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, 100);
1334 let counterparty_package = PackageTemplate::build_package(txid, 1, counterparty_outp, 1000, 100);
1335 revoked_package.merge_package(counterparty_package);
1339 fn test_package_split_malleable() {
1340 let txid = Txid::from_str("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1341 let secp_ctx = Secp256k1::new();
1342 let revk_outp_one = dumb_revk_output!(secp_ctx, false);
1343 let revk_outp_two = dumb_revk_output!(secp_ctx, false);
1344 let revk_outp_three = dumb_revk_output!(secp_ctx, false);
1346 let mut package_one = PackageTemplate::build_package(txid, 0, revk_outp_one, 1000, 100);
1347 let package_two = PackageTemplate::build_package(txid, 1, revk_outp_two, 1000, 100);
1348 let package_three = PackageTemplate::build_package(txid, 2, revk_outp_three, 1000, 100);
1350 package_one.merge_package(package_two);
1351 package_one.merge_package(package_three);
1352 assert_eq!(package_one.outpoints().len(), 3);
1354 if let Some(split_package) = package_one.split_package(&BitcoinOutPoint { txid, vout: 1 }) {
1355 // Packages attributes should be identical
1356 assert!(split_package.is_malleable());
1357 assert_eq!(split_package.soonest_conf_deadline, package_one.soonest_conf_deadline);
1358 assert_eq!(split_package.aggregable, package_one.aggregable);
1359 assert_eq!(split_package.feerate_previous, package_one.feerate_previous);
1360 assert_eq!(split_package.height_timer, package_one.height_timer);
1361 assert_eq!(split_package.height_original, package_one.height_original);
1362 } else { panic!(); }
1363 assert_eq!(package_one.outpoints().len(), 2);
1367 fn test_package_split_untractable() {
1368 let txid = Txid::from_str("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1369 let htlc_outp_one = dumb_htlc_output!();
1371 let mut package_one = PackageTemplate::build_package(txid, 0, htlc_outp_one, 1000, 100);
1372 let ret_split = package_one.split_package(&BitcoinOutPoint { txid, vout: 0});
1373 assert!(ret_split.is_none());
1377 fn test_package_timer() {
1378 let txid = Txid::from_str("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1379 let secp_ctx = Secp256k1::new();
1380 let revk_outp = dumb_revk_output!(secp_ctx, false);
1382 let mut package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, 100);
1383 assert_eq!(package.timer(), 100);
1384 package.set_timer(101);
1385 assert_eq!(package.timer(), 101);
1389 fn test_package_amounts() {
1390 let txid = Txid::from_str("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1391 let secp_ctx = Secp256k1::new();
1392 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 1_000_000, ChannelTypeFeatures::only_static_remote_key());
1394 let package = PackageTemplate::build_package(txid, 0, counterparty_outp, 1000, 100);
1395 assert_eq!(package.package_amount(), 1000);
1399 fn test_package_weight() {
1400 let txid = Txid::from_str("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1401 let secp_ctx = Secp256k1::new();
1403 // (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)
1404 let weight_sans_output = (4 + 4 + 1 + 36 + 4 + 1 + 1 + 8 + 1) * WITNESS_SCALE_FACTOR as u64 + 2;
1407 let revk_outp = dumb_revk_output!(secp_ctx, false);
1408 let package = PackageTemplate::build_package(txid, 0, revk_outp, 0, 100);
1409 assert_eq!(package.package_weight(&ScriptBuf::new()), weight_sans_output + WEIGHT_REVOKED_OUTPUT);
1413 for channel_type_features in [ChannelTypeFeatures::only_static_remote_key(), ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()].iter() {
1414 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 1_000_000, channel_type_features.clone());
1415 let package = PackageTemplate::build_package(txid, 0, counterparty_outp, 1000, 100);
1416 assert_eq!(package.package_weight(&ScriptBuf::new()), weight_sans_output + weight_received_htlc(channel_type_features));
1421 for channel_type_features in [ChannelTypeFeatures::only_static_remote_key(), ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()].iter() {
1422 let counterparty_outp = dumb_counterparty_offered_output!(secp_ctx, 1_000_000, channel_type_features.clone());
1423 let package = PackageTemplate::build_package(txid, 0, counterparty_outp, 1000, 100);
1424 assert_eq!(package.package_weight(&ScriptBuf::new()), weight_sans_output + weight_offered_htlc(channel_type_features));