]> git.bitcoin.ninja Git - rust-lightning/blob - lightning/src/chain/package.rs
Merge pull request #2589 from ErikDeSmedt/reexport_route_hint_hop
[rust-lightning] / lightning / src / chain / package.rs
1 // This file is Copyright its original authors, visible in version control
2 // history.
3 //
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
8 // licenses.
9
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.
13
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;
18
19 use bitcoin::hash_types::Txid;
20
21 use bitcoin::secp256k1::{SecretKey,PublicKey};
22
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;
29 use crate::chain::onchaintx::{ExternalHTLCClaim, OnchainTxHandler};
30 use crate::util::logger::Logger;
31 use crate::util::ser::{Readable, Writer, Writeable, RequiredWrapper};
32
33 use crate::io;
34 use crate::prelude::*;
35 use core::cmp;
36 use core::convert::TryInto;
37 use core::mem;
38 use core::ops::Deref;
39 use bitcoin::{PackedLockTime, Sequence, Witness};
40 use crate::ln::features::ChannelTypeFeatures;
41
42 use super::chaininterface::LowerBoundedFeeEstimator;
43
44 const MAX_ALLOC_SIZE: usize = 64*1024;
45
46
47 pub(crate) fn weight_revoked_offered_htlc(channel_type_features: &ChannelTypeFeatures) -> u64 {
48         // number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
49         const WEIGHT_REVOKED_OFFERED_HTLC: u64 = 1 + 1 + 73 + 1 + 33 + 1 + 133;
50         const WEIGHT_REVOKED_OFFERED_HTLC_ANCHORS: u64 = WEIGHT_REVOKED_OFFERED_HTLC + 3; // + OP_1 + OP_CSV + OP_DROP
51         if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_REVOKED_OFFERED_HTLC_ANCHORS } else { WEIGHT_REVOKED_OFFERED_HTLC }
52 }
53
54 pub(crate) fn weight_revoked_received_htlc(channel_type_features: &ChannelTypeFeatures) -> u64 {
55         // number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
56         const WEIGHT_REVOKED_RECEIVED_HTLC: u64 = 1 + 1 + 73 + 1 + 33 + 1 +  139;
57         const WEIGHT_REVOKED_RECEIVED_HTLC_ANCHORS: u64 = WEIGHT_REVOKED_RECEIVED_HTLC + 3; // + OP_1 + OP_CSV + OP_DROP
58         if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_REVOKED_RECEIVED_HTLC_ANCHORS } else { WEIGHT_REVOKED_RECEIVED_HTLC }
59 }
60
61 pub(crate) fn weight_offered_htlc(channel_type_features: &ChannelTypeFeatures) -> u64 {
62         // number_of_witness_elements + sig_length + counterpartyhtlc_sig  + preimage_length + preimage + witness_script_length + witness_script
63         const WEIGHT_OFFERED_HTLC: u64 = 1 + 1 + 73 + 1 + 32 + 1 + 133;
64         const WEIGHT_OFFERED_HTLC_ANCHORS: u64 = WEIGHT_OFFERED_HTLC + 3; // + OP_1 + OP_CSV + OP_DROP
65         if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_OFFERED_HTLC_ANCHORS } else { WEIGHT_OFFERED_HTLC }
66 }
67
68 pub(crate) fn weight_received_htlc(channel_type_features: &ChannelTypeFeatures) -> u64 {
69         // number_of_witness_elements + sig_length + counterpartyhtlc_sig + empty_vec_length + empty_vec + witness_script_length + witness_script
70         const WEIGHT_RECEIVED_HTLC: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 139;
71         const WEIGHT_RECEIVED_HTLC_ANCHORS: u64 = WEIGHT_RECEIVED_HTLC + 3; // + OP_1 + OP_CSV + OP_DROP
72         if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_RECEIVED_HTLC_ANCHORS } else { WEIGHT_RECEIVED_HTLC }
73 }
74
75 /// Verifies deserializable channel type features
76 pub(crate) fn verify_channel_type_features(channel_type_features: &Option<ChannelTypeFeatures>, additional_permitted_features: Option<&ChannelTypeFeatures>) -> Result<(), DecodeError> {
77         if let Some(features) = channel_type_features.as_ref() {
78                 if features.requires_unknown_bits() {
79                         return Err(DecodeError::UnknownRequiredFeature);
80                 }
81
82                 let mut supported_feature_set = ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies();
83                 supported_feature_set.set_scid_privacy_required();
84                 supported_feature_set.set_zero_conf_required();
85
86                 // allow the passing of an additional necessary permitted flag
87                 if let Some(additional_permitted_features) = additional_permitted_features {
88                         supported_feature_set |= additional_permitted_features;
89                 }
90
91                 if !features.is_subset(&supported_feature_set) {
92                         return Err(DecodeError::UnknownRequiredFeature);
93                 }
94         }
95
96         Ok(())
97 }
98
99 // number_of_witness_elements + sig_length + revocation_sig + true_length + op_true + witness_script_length + witness_script
100 pub(crate) const WEIGHT_REVOKED_OUTPUT: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 77;
101
102 /// Height delay at which transactions are fee-bumped/rebroadcasted with a low priority.
103 const LOW_FREQUENCY_BUMP_INTERVAL: u32 = 15;
104 /// Height delay at which transactions are fee-bumped/rebroadcasted with a middle priority.
105 const MIDDLE_FREQUENCY_BUMP_INTERVAL: u32 = 3;
106 /// Height delay at which transactions are fee-bumped/rebroadcasted with a high priority.
107 const HIGH_FREQUENCY_BUMP_INTERVAL: u32 = 1;
108
109 /// A struct to describe a revoked output and corresponding information to generate a solving
110 /// witness spending a commitment `to_local` output or a second-stage HTLC transaction output.
111 ///
112 /// CSV and pubkeys are used as part of a witnessScript redeeming a balance output, amount is used
113 /// as part of the signature hash and revocation secret to generate a satisfying witness.
114 #[derive(Clone, PartialEq, Eq)]
115 pub(crate) struct RevokedOutput {
116         per_commitment_point: PublicKey,
117         counterparty_delayed_payment_base_key: PublicKey,
118         counterparty_htlc_base_key: PublicKey,
119         per_commitment_key: SecretKey,
120         weight: u64,
121         amount: u64,
122         on_counterparty_tx_csv: u16,
123         is_counterparty_balance_on_anchors: Option<()>,
124 }
125
126 impl RevokedOutput {
127         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 {
128                 RevokedOutput {
129                         per_commitment_point,
130                         counterparty_delayed_payment_base_key,
131                         counterparty_htlc_base_key,
132                         per_commitment_key,
133                         weight: WEIGHT_REVOKED_OUTPUT,
134                         amount,
135                         on_counterparty_tx_csv,
136                         is_counterparty_balance_on_anchors: if is_counterparty_balance_on_anchors { Some(()) } else { None }
137                 }
138         }
139 }
140
141 impl_writeable_tlv_based!(RevokedOutput, {
142         (0, per_commitment_point, required),
143         (2, counterparty_delayed_payment_base_key, required),
144         (4, counterparty_htlc_base_key, required),
145         (6, per_commitment_key, required),
146         (8, weight, required),
147         (10, amount, required),
148         (12, on_counterparty_tx_csv, required),
149         (14, is_counterparty_balance_on_anchors, option)
150 });
151
152 /// A struct to describe a revoked offered output and corresponding information to generate a
153 /// solving witness.
154 ///
155 /// HTLCOuputInCommitment (hash timelock, direction) and pubkeys are used to generate a suitable
156 /// witnessScript.
157 ///
158 /// CSV is used as part of a witnessScript redeeming a balance output, amount is used as part
159 /// of the signature hash and revocation secret to generate a satisfying witness.
160 #[derive(Clone, PartialEq, Eq)]
161 pub(crate) struct RevokedHTLCOutput {
162         per_commitment_point: PublicKey,
163         counterparty_delayed_payment_base_key: PublicKey,
164         counterparty_htlc_base_key: PublicKey,
165         per_commitment_key: SecretKey,
166         weight: u64,
167         amount: u64,
168         htlc: HTLCOutputInCommitment,
169 }
170
171 impl RevokedHTLCOutput {
172         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 {
173                 let weight = if htlc.offered { weight_revoked_offered_htlc(channel_type_features) } else { weight_revoked_received_htlc(channel_type_features) };
174                 RevokedHTLCOutput {
175                         per_commitment_point,
176                         counterparty_delayed_payment_base_key,
177                         counterparty_htlc_base_key,
178                         per_commitment_key,
179                         weight,
180                         amount,
181                         htlc
182                 }
183         }
184 }
185
186 impl_writeable_tlv_based!(RevokedHTLCOutput, {
187         (0, per_commitment_point, required),
188         (2, counterparty_delayed_payment_base_key, required),
189         (4, counterparty_htlc_base_key, required),
190         (6, per_commitment_key, required),
191         (8, weight, required),
192         (10, amount, required),
193         (12, htlc, required),
194 });
195
196 /// A struct to describe a HTLC output on a counterparty commitment transaction.
197 ///
198 /// HTLCOutputInCommitment (hash, timelock, directon) and pubkeys are used to generate a suitable
199 /// witnessScript.
200 ///
201 /// The preimage is used as part of the witness.
202 ///
203 /// Note that on upgrades, some features of existing outputs may be missed.
204 #[derive(Clone, PartialEq, Eq)]
205 pub(crate) struct CounterpartyOfferedHTLCOutput {
206         per_commitment_point: PublicKey,
207         counterparty_delayed_payment_base_key: PublicKey,
208         counterparty_htlc_base_key: PublicKey,
209         preimage: PaymentPreimage,
210         htlc: HTLCOutputInCommitment,
211         channel_type_features: ChannelTypeFeatures,
212 }
213
214 impl CounterpartyOfferedHTLCOutput {
215         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 {
216                 CounterpartyOfferedHTLCOutput {
217                         per_commitment_point,
218                         counterparty_delayed_payment_base_key,
219                         counterparty_htlc_base_key,
220                         preimage,
221                         htlc,
222                         channel_type_features,
223                 }
224         }
225 }
226
227 impl Writeable for CounterpartyOfferedHTLCOutput {
228         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
229                 let legacy_deserialization_prevention_marker = chan_utils::legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
230                 write_tlv_fields!(writer, {
231                         (0, self.per_commitment_point, required),
232                         (2, self.counterparty_delayed_payment_base_key, required),
233                         (4, self.counterparty_htlc_base_key, required),
234                         (6, self.preimage, required),
235                         (8, self.htlc, required),
236                         (10, legacy_deserialization_prevention_marker, option),
237                         (11, self.channel_type_features, required),
238                 });
239                 Ok(())
240         }
241 }
242
243 impl Readable for CounterpartyOfferedHTLCOutput {
244         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
245                 let mut per_commitment_point = RequiredWrapper(None);
246                 let mut counterparty_delayed_payment_base_key = RequiredWrapper(None);
247                 let mut counterparty_htlc_base_key = RequiredWrapper(None);
248                 let mut preimage = RequiredWrapper(None);
249                 let mut htlc = RequiredWrapper(None);
250                 let mut _legacy_deserialization_prevention_marker: Option<()> = None;
251                 let mut channel_type_features = None;
252
253                 read_tlv_fields!(reader, {
254                         (0, per_commitment_point, required),
255                         (2, counterparty_delayed_payment_base_key, required),
256                         (4, counterparty_htlc_base_key, required),
257                         (6, preimage, required),
258                         (8, htlc, required),
259                         (10, _legacy_deserialization_prevention_marker, option),
260                         (11, channel_type_features, option),
261                 });
262
263                 verify_channel_type_features(&channel_type_features, None)?;
264
265                 Ok(Self {
266                         per_commitment_point: per_commitment_point.0.unwrap(),
267                         counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
268                         counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
269                         preimage: preimage.0.unwrap(),
270                         htlc: htlc.0.unwrap(),
271                         channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
272                 })
273         }
274 }
275
276 /// A struct to describe a HTLC output on a counterparty commitment transaction.
277 ///
278 /// HTLCOutputInCommitment (hash, timelock, directon) and pubkeys are used to generate a suitable
279 /// witnessScript.
280 ///
281 /// Note that on upgrades, some features of existing outputs may be missed.
282 #[derive(Clone, PartialEq, Eq)]
283 pub(crate) struct CounterpartyReceivedHTLCOutput {
284         per_commitment_point: PublicKey,
285         counterparty_delayed_payment_base_key: PublicKey,
286         counterparty_htlc_base_key: PublicKey,
287         htlc: HTLCOutputInCommitment,
288         channel_type_features: ChannelTypeFeatures,
289 }
290
291 impl CounterpartyReceivedHTLCOutput {
292         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 {
293                 CounterpartyReceivedHTLCOutput {
294                         per_commitment_point,
295                         counterparty_delayed_payment_base_key,
296                         counterparty_htlc_base_key,
297                         htlc,
298                         channel_type_features
299                 }
300         }
301 }
302
303 impl Writeable for CounterpartyReceivedHTLCOutput {
304         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
305                 let legacy_deserialization_prevention_marker = chan_utils::legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
306                 write_tlv_fields!(writer, {
307                         (0, self.per_commitment_point, required),
308                         (2, self.counterparty_delayed_payment_base_key, required),
309                         (4, self.counterparty_htlc_base_key, required),
310                         (6, self.htlc, required),
311                         (8, legacy_deserialization_prevention_marker, option),
312                         (9, self.channel_type_features, required),
313                 });
314                 Ok(())
315         }
316 }
317
318 impl Readable for CounterpartyReceivedHTLCOutput {
319         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
320                 let mut per_commitment_point = RequiredWrapper(None);
321                 let mut counterparty_delayed_payment_base_key = RequiredWrapper(None);
322                 let mut counterparty_htlc_base_key = RequiredWrapper(None);
323                 let mut htlc = RequiredWrapper(None);
324                 let mut _legacy_deserialization_prevention_marker: Option<()> = None;
325                 let mut channel_type_features = None;
326
327                 read_tlv_fields!(reader, {
328                         (0, per_commitment_point, required),
329                         (2, counterparty_delayed_payment_base_key, required),
330                         (4, counterparty_htlc_base_key, required),
331                         (6, htlc, required),
332                         (8, _legacy_deserialization_prevention_marker, option),
333                         (9, channel_type_features, option),
334                 });
335
336                 verify_channel_type_features(&channel_type_features, None)?;
337
338                 Ok(Self {
339                         per_commitment_point: per_commitment_point.0.unwrap(),
340                         counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
341                         counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
342                         htlc: htlc.0.unwrap(),
343                         channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
344                 })
345         }
346 }
347
348 /// A struct to describe a HTLC output on holder commitment transaction.
349 ///
350 /// Either offered or received, the amount is always used as part of the bip143 sighash.
351 /// Preimage is only included as part of the witness in former case.
352 ///
353 /// Note that on upgrades, some features of existing outputs may be missed.
354 #[derive(Clone, PartialEq, Eq)]
355 pub(crate) struct HolderHTLCOutput {
356         preimage: Option<PaymentPreimage>,
357         amount_msat: u64,
358         /// Defaults to 0 for HTLC-Success transactions, which have no expiry
359         cltv_expiry: u32,
360         channel_type_features: ChannelTypeFeatures,
361 }
362
363 impl HolderHTLCOutput {
364         pub(crate) fn build_offered(amount_msat: u64, cltv_expiry: u32, channel_type_features: ChannelTypeFeatures) -> Self {
365                 HolderHTLCOutput {
366                         preimage: None,
367                         amount_msat,
368                         cltv_expiry,
369                         channel_type_features,
370                 }
371         }
372
373         pub(crate) fn build_accepted(preimage: PaymentPreimage, amount_msat: u64, channel_type_features: ChannelTypeFeatures) -> Self {
374                 HolderHTLCOutput {
375                         preimage: Some(preimage),
376                         amount_msat,
377                         cltv_expiry: 0,
378                         channel_type_features,
379                 }
380         }
381 }
382
383 impl Writeable for HolderHTLCOutput {
384         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
385                 let legacy_deserialization_prevention_marker = chan_utils::legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
386                 write_tlv_fields!(writer, {
387                         (0, self.amount_msat, required),
388                         (2, self.cltv_expiry, required),
389                         (4, self.preimage, option),
390                         (6, legacy_deserialization_prevention_marker, option),
391                         (7, self.channel_type_features, required),
392                 });
393                 Ok(())
394         }
395 }
396
397 impl Readable for HolderHTLCOutput {
398         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
399                 let mut amount_msat = RequiredWrapper(None);
400                 let mut cltv_expiry = RequiredWrapper(None);
401                 let mut preimage = None;
402                 let mut _legacy_deserialization_prevention_marker: Option<()> = None;
403                 let mut channel_type_features = None;
404
405                 read_tlv_fields!(reader, {
406                         (0, amount_msat, required),
407                         (2, cltv_expiry, required),
408                         (4, preimage, option),
409                         (6, _legacy_deserialization_prevention_marker, option),
410                         (7, channel_type_features, option),
411                 });
412
413                 verify_channel_type_features(&channel_type_features, None)?;
414
415                 Ok(Self {
416                         amount_msat: amount_msat.0.unwrap(),
417                         cltv_expiry: cltv_expiry.0.unwrap(),
418                         preimage,
419                         channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key())
420                 })
421         }
422 }
423
424 /// A struct to describe the channel output on the funding transaction.
425 ///
426 /// witnessScript is used as part of the witness redeeming the funding utxo.
427 ///
428 /// Note that on upgrades, some features of existing outputs may be missed.
429 #[derive(Clone, PartialEq, Eq)]
430 pub(crate) struct HolderFundingOutput {
431         funding_redeemscript: Script,
432         pub(crate) funding_amount: Option<u64>,
433         channel_type_features: ChannelTypeFeatures,
434 }
435
436
437 impl HolderFundingOutput {
438         pub(crate) fn build(funding_redeemscript: Script, funding_amount: u64, channel_type_features: ChannelTypeFeatures) -> Self {
439                 HolderFundingOutput {
440                         funding_redeemscript,
441                         funding_amount: Some(funding_amount),
442                         channel_type_features,
443                 }
444         }
445 }
446
447 impl Writeable for HolderFundingOutput {
448         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
449                 let legacy_deserialization_prevention_marker = chan_utils::legacy_deserialization_prevention_marker_for_channel_type_features(&self.channel_type_features);
450                 write_tlv_fields!(writer, {
451                         (0, self.funding_redeemscript, required),
452                         (1, self.channel_type_features, required),
453                         (2, legacy_deserialization_prevention_marker, option),
454                         (3, self.funding_amount, option),
455                 });
456                 Ok(())
457         }
458 }
459
460 impl Readable for HolderFundingOutput {
461         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
462                 let mut funding_redeemscript = RequiredWrapper(None);
463                 let mut _legacy_deserialization_prevention_marker: Option<()> = None;
464                 let mut channel_type_features = None;
465                 let mut funding_amount = None;
466
467                 read_tlv_fields!(reader, {
468                         (0, funding_redeemscript, required),
469                         (1, channel_type_features, option),
470                         (2, _legacy_deserialization_prevention_marker, option),
471                         (3, funding_amount, option)
472                 });
473
474                 verify_channel_type_features(&channel_type_features, None)?;
475
476                 Ok(Self {
477                         funding_redeemscript: funding_redeemscript.0.unwrap(),
478                         channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key()),
479                         funding_amount
480                 })
481         }
482 }
483
484 /// A wrapper encapsulating all in-protocol differing outputs types.
485 ///
486 /// The generic API offers access to an outputs common attributes or allow transformation such as
487 /// finalizing an input claiming the output.
488 #[derive(Clone, PartialEq, Eq)]
489 pub(crate) enum PackageSolvingData {
490         RevokedOutput(RevokedOutput),
491         RevokedHTLCOutput(RevokedHTLCOutput),
492         CounterpartyOfferedHTLCOutput(CounterpartyOfferedHTLCOutput),
493         CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput),
494         HolderHTLCOutput(HolderHTLCOutput),
495         HolderFundingOutput(HolderFundingOutput),
496 }
497
498 impl PackageSolvingData {
499         fn amount(&self) -> u64 {
500                 let amt = match self {
501                         PackageSolvingData::RevokedOutput(ref outp) => outp.amount,
502                         PackageSolvingData::RevokedHTLCOutput(ref outp) => outp.amount,
503                         PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => outp.htlc.amount_msat / 1000,
504                         PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => outp.htlc.amount_msat / 1000,
505                         PackageSolvingData::HolderHTLCOutput(ref outp) => {
506                                 debug_assert!(outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
507                                 outp.amount_msat / 1000
508                         },
509                         PackageSolvingData::HolderFundingOutput(ref outp) => {
510                                 debug_assert!(outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
511                                 outp.funding_amount.unwrap()
512                         }
513                 };
514                 amt
515         }
516         fn weight(&self) -> usize {
517                 match self {
518                         PackageSolvingData::RevokedOutput(ref outp) => outp.weight as usize,
519                         PackageSolvingData::RevokedHTLCOutput(ref outp) => outp.weight as usize,
520                         PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => weight_offered_htlc(&outp.channel_type_features) as usize,
521                         PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => weight_received_htlc(&outp.channel_type_features) as usize,
522                         PackageSolvingData::HolderHTLCOutput(ref outp) => {
523                                 debug_assert!(outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
524                                 if outp.preimage.is_none() {
525                                         weight_offered_htlc(&outp.channel_type_features) as usize
526                                 } else {
527                                         weight_received_htlc(&outp.channel_type_features) as usize
528                                 }
529                         },
530                         // Since HolderFundingOutput maps to an untractable package that is already signed, its
531                         // weight can be determined from the transaction itself.
532                         PackageSolvingData::HolderFundingOutput(..) => unreachable!(),
533                 }
534         }
535         fn is_compatible(&self, input: &PackageSolvingData) -> bool {
536                 match self {
537                         PackageSolvingData::RevokedOutput(..) => {
538                                 match input {
539                                         PackageSolvingData::RevokedHTLCOutput(..) => { true },
540                                         PackageSolvingData::RevokedOutput(..) => { true },
541                                         _ => { false }
542                                 }
543                         },
544                         PackageSolvingData::RevokedHTLCOutput(..) => {
545                                 match input {
546                                         PackageSolvingData::RevokedOutput(..) => { true },
547                                         PackageSolvingData::RevokedHTLCOutput(..) => { true },
548                                         _ => { false }
549                                 }
550                         },
551                         _ => { mem::discriminant(self) == mem::discriminant(&input) }
552                 }
553         }
554         fn finalize_input<Signer: WriteableEcdsaChannelSigner>(&self, bumped_tx: &mut Transaction, i: usize, onchain_handler: &mut OnchainTxHandler<Signer>) -> bool {
555                 match self {
556                         PackageSolvingData::RevokedOutput(ref outp) => {
557                                 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);
558                                 let witness_script = chan_utils::get_revokeable_redeemscript(&chan_keys.revocation_key, outp.on_counterparty_tx_csv, &chan_keys.broadcaster_delayed_payment_key);
559                                 //TODO: should we panic on signer failure ?
560                                 if let Ok(sig) = onchain_handler.signer.sign_justice_revoked_output(&bumped_tx, i, outp.amount, &outp.per_commitment_key, &onchain_handler.secp_ctx) {
561                                         let mut ser_sig = sig.serialize_der().to_vec();
562                                         ser_sig.push(EcdsaSighashType::All as u8);
563                                         bumped_tx.input[i].witness.push(ser_sig);
564                                         bumped_tx.input[i].witness.push(vec!(1));
565                                         bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
566                                 } else { return false; }
567                         },
568                         PackageSolvingData::RevokedHTLCOutput(ref outp) => {
569                                 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);
570                                 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);
571                                 //TODO: should we panic on signer failure ?
572                                 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) {
573                                         let mut ser_sig = sig.serialize_der().to_vec();
574                                         ser_sig.push(EcdsaSighashType::All as u8);
575                                         bumped_tx.input[i].witness.push(ser_sig);
576                                         bumped_tx.input[i].witness.push(chan_keys.revocation_key.clone().serialize().to_vec());
577                                         bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
578                                 } else { return false; }
579                         },
580                         PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => {
581                                 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);
582                                 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);
583
584                                 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) {
585                                         let mut ser_sig = sig.serialize_der().to_vec();
586                                         ser_sig.push(EcdsaSighashType::All as u8);
587                                         bumped_tx.input[i].witness.push(ser_sig);
588                                         bumped_tx.input[i].witness.push(outp.preimage.0.to_vec());
589                                         bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
590                                 }
591                         },
592                         PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => {
593                                 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);
594                                 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);
595
596                                 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) {
597                                         let mut ser_sig = sig.serialize_der().to_vec();
598                                         ser_sig.push(EcdsaSighashType::All as u8);
599                                         bumped_tx.input[i].witness.push(ser_sig);
600                                         // Due to BIP146 (MINIMALIF) this must be a zero-length element to relay.
601                                         bumped_tx.input[i].witness.push(vec![]);
602                                         bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
603                                 }
604                         },
605                         _ => { panic!("API Error!"); }
606                 }
607                 true
608         }
609         fn get_finalized_tx<Signer: WriteableEcdsaChannelSigner>(&self, outpoint: &BitcoinOutPoint, onchain_handler: &mut OnchainTxHandler<Signer>) -> Option<Transaction> {
610                 match self {
611                         PackageSolvingData::HolderHTLCOutput(ref outp) => {
612                                 debug_assert!(!outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
613                                 return onchain_handler.get_fully_signed_htlc_tx(outpoint, &outp.preimage);
614                         }
615                         PackageSolvingData::HolderFundingOutput(ref outp) => {
616                                 return Some(onchain_handler.get_fully_signed_holder_tx(&outp.funding_redeemscript));
617                         }
618                         _ => { panic!("API Error!"); }
619                 }
620         }
621         fn absolute_tx_timelock(&self, current_height: u32) -> u32 {
622                 // We use `current_height` as our default locktime to discourage fee sniping and because
623                 // transactions with it always propagate.
624                 let absolute_timelock = match self {
625                         PackageSolvingData::RevokedOutput(_) => current_height,
626                         PackageSolvingData::RevokedHTLCOutput(_) => current_height,
627                         PackageSolvingData::CounterpartyOfferedHTLCOutput(_) => current_height,
628                         PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => cmp::max(outp.htlc.cltv_expiry, current_height),
629                         // HTLC timeout/success transactions rely on a fixed timelock due to the counterparty's
630                         // signature.
631                         PackageSolvingData::HolderHTLCOutput(ref outp) => {
632                                 if outp.preimage.is_some() {
633                                         debug_assert_eq!(outp.cltv_expiry, 0);
634                                 }
635                                 outp.cltv_expiry
636                         },
637                         PackageSolvingData::HolderFundingOutput(_) => current_height,
638                 };
639                 absolute_timelock
640         }
641
642         fn map_output_type_flags(&self) -> (PackageMalleability, bool) {
643                 // Post-anchor, aggregation of outputs of different types is unsafe. See https://github.com/lightning/bolts/pull/803.
644                 let (malleability, aggregable) = match self {
645                         PackageSolvingData::RevokedOutput(RevokedOutput { is_counterparty_balance_on_anchors: Some(()), .. }) => { (PackageMalleability::Malleable, false) },
646                         PackageSolvingData::RevokedOutput(RevokedOutput { is_counterparty_balance_on_anchors: None, .. }) => { (PackageMalleability::Malleable, true) },
647                         PackageSolvingData::RevokedHTLCOutput(..) => { (PackageMalleability::Malleable, true) },
648                         PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { (PackageMalleability::Malleable, true) },
649                         PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { (PackageMalleability::Malleable, false) },
650                         PackageSolvingData::HolderHTLCOutput(ref outp) => if outp.channel_type_features.supports_anchors_zero_fee_htlc_tx() {
651                                 (PackageMalleability::Malleable, outp.preimage.is_some())
652                         } else {
653                                 (PackageMalleability::Untractable, false)
654                         },
655                         PackageSolvingData::HolderFundingOutput(..) => { (PackageMalleability::Untractable, false) },
656                 };
657                 (malleability, aggregable)
658         }
659 }
660
661 impl_writeable_tlv_based_enum!(PackageSolvingData, ;
662         (0, RevokedOutput),
663         (1, RevokedHTLCOutput),
664         (2, CounterpartyOfferedHTLCOutput),
665         (3, CounterpartyReceivedHTLCOutput),
666         (4, HolderHTLCOutput),
667         (5, HolderFundingOutput),
668 );
669
670 /// A malleable package might be aggregated with other packages to save on fees.
671 /// A untractable package has been counter-signed and aggregable will break cached counterparty signatures.
672 #[derive(Clone, PartialEq, Eq)]
673 pub(crate) enum PackageMalleability {
674         Malleable,
675         Untractable,
676 }
677
678 /// A structure to describe a package content that is generated by ChannelMonitor and
679 /// used by OnchainTxHandler to generate and broadcast transactions settling onchain claims.
680 ///
681 /// A package is defined as one or more transactions claiming onchain outputs in reaction
682 /// to confirmation of a channel transaction. Those packages might be aggregated to save on
683 /// fees, if satisfaction of outputs's witnessScript let's us do so.
684 ///
685 /// As packages are time-sensitive, we fee-bump and rebroadcast them at scheduled intervals.
686 /// Failing to confirm a package translate as a loss of funds for the user.
687 #[derive(Clone, PartialEq, Eq)]
688 pub struct PackageTemplate {
689         // List of onchain outputs and solving data to generate satisfying witnesses.
690         inputs: Vec<(BitcoinOutPoint, PackageSolvingData)>,
691         // Packages are deemed as malleable if we have local knwoledge of at least one set of
692         // private keys yielding a satisfying witnesses. Malleability implies that we can aggregate
693         // packages among them to save on fees or rely on RBF to bump their feerates.
694         // Untractable packages have been counter-signed and thus imply that we can't aggregate
695         // them without breaking signatures. Fee-bumping strategy will also rely on CPFP.
696         malleability: PackageMalleability,
697         // Block height after which the earlier-output belonging to this package is mature for a
698         // competing claim by the counterparty. As our chain tip becomes nearer from the timelock,
699         // the fee-bumping frequency will increase. See `OnchainTxHandler::get_height_timer`.
700         soonest_conf_deadline: u32,
701         // Determines if this package can be aggregated.
702         // Timelocked outputs belonging to the same transaction might have differing
703         // satisfying heights. Picking up the later height among the output set would be a valid
704         // aggregable strategy but it comes with at least 2 trade-offs :
705         // * earlier-output fund are going to take longer to come back
706         // * CLTV delta backing up a corresponding HTLC on an upstream channel could be swallowed
707         // by the requirement of the later-output part of the set
708         // For now, we mark such timelocked outputs as non-aggregable, though we might introduce
709         // smarter aggregable strategy in the future.
710         aggregable: bool,
711         // Cache of package feerate committed at previous (re)broadcast. If bumping resources
712         // (either claimed output value or external utxo), it will keep increasing until holder
713         // or counterparty successful claim.
714         feerate_previous: u64,
715         // Cache of next height at which fee-bumping and rebroadcast will be attempted. In
716         // the future, we might abstract it to an observed mempool fluctuation.
717         height_timer: u32,
718         // Confirmation height of the claimed outputs set transaction. In case of reorg reaching
719         // it, we wipe out and forget the package.
720         height_original: u32,
721 }
722
723 impl PackageTemplate {
724         pub(crate) fn is_malleable(&self) -> bool {
725                 self.malleability == PackageMalleability::Malleable
726         }
727         pub(crate) fn timelock(&self) -> u32 {
728                 self.soonest_conf_deadline
729         }
730         pub(crate) fn aggregable(&self) -> bool {
731                 self.aggregable
732         }
733         pub(crate) fn previous_feerate(&self) -> u64 {
734                 self.feerate_previous
735         }
736         pub(crate) fn set_feerate(&mut self, new_feerate: u64) {
737                 self.feerate_previous = new_feerate;
738         }
739         pub(crate) fn timer(&self) -> u32 {
740                 self.height_timer
741         }
742         pub(crate) fn set_timer(&mut self, new_timer: u32) {
743                 self.height_timer = new_timer;
744         }
745         pub(crate) fn outpoints(&self) -> Vec<&BitcoinOutPoint> {
746                 self.inputs.iter().map(|(o, _)| o).collect()
747         }
748         pub(crate) fn inputs(&self) -> impl ExactSizeIterator<Item = &PackageSolvingData> {
749                 self.inputs.iter().map(|(_, i)| i)
750         }
751         pub(crate) fn split_package(&mut self, split_outp: &BitcoinOutPoint) -> Option<PackageTemplate> {
752                 match self.malleability {
753                         PackageMalleability::Malleable => {
754                                 let mut split_package = None;
755                                 let timelock = self.soonest_conf_deadline;
756                                 let aggregable = self.aggregable;
757                                 let feerate_previous = self.feerate_previous;
758                                 let height_timer = self.height_timer;
759                                 let height_original = self.height_original;
760                                 self.inputs.retain(|outp| {
761                                         if *split_outp == outp.0 {
762                                                 split_package = Some(PackageTemplate {
763                                                         inputs: vec![(outp.0, outp.1.clone())],
764                                                         malleability: PackageMalleability::Malleable,
765                                                         soonest_conf_deadline: timelock,
766                                                         aggregable,
767                                                         feerate_previous,
768                                                         height_timer,
769                                                         height_original,
770                                                 });
771                                                 return false;
772                                         }
773                                         return true;
774                                 });
775                                 return split_package;
776                         },
777                         _ => {
778                                 // Note, we may try to split on remote transaction for
779                                 // which we don't have a competing one (HTLC-Success before
780                                 // timelock expiration). This explain we don't panic!
781                                 // We should refactor OnchainTxHandler::block_connected to
782                                 // only test equality on competing claims.
783                                 return None;
784                         }
785                 }
786         }
787         pub(crate) fn merge_package(&mut self, mut merge_from: PackageTemplate) {
788                 assert_eq!(self.height_original, merge_from.height_original);
789                 if self.malleability == PackageMalleability::Untractable || merge_from.malleability == PackageMalleability::Untractable {
790                         panic!("Merging template on untractable packages");
791                 }
792                 if !self.aggregable || !merge_from.aggregable {
793                         panic!("Merging non aggregatable packages");
794                 }
795                 if let Some((_, lead_input)) = self.inputs.first() {
796                         for (_, v) in merge_from.inputs.iter() {
797                                 if !lead_input.is_compatible(v) { panic!("Merging outputs from differing types !"); }
798                         }
799                 } else { panic!("Merging template on an empty package"); }
800                 for (k, v) in merge_from.inputs.drain(..) {
801                         self.inputs.push((k, v));
802                 }
803                 //TODO: verify coverage and sanity?
804                 if self.soonest_conf_deadline > merge_from.soonest_conf_deadline {
805                         self.soonest_conf_deadline = merge_from.soonest_conf_deadline;
806                 }
807                 if self.feerate_previous > merge_from.feerate_previous {
808                         self.feerate_previous = merge_from.feerate_previous;
809                 }
810                 self.height_timer = cmp::min(self.height_timer, merge_from.height_timer);
811         }
812         /// Gets the amount of all outptus being spent by this package, only valid for malleable
813         /// packages.
814         pub(crate) fn package_amount(&self) -> u64 {
815                 let mut amounts = 0;
816                 for (_, outp) in self.inputs.iter() {
817                         amounts += outp.amount();
818                 }
819                 amounts
820         }
821         pub(crate) fn package_locktime(&self, current_height: u32) -> u32 {
822                 let locktime = self.inputs.iter().map(|(_, outp)| outp.absolute_tx_timelock(current_height))
823                         .max().expect("There must always be at least one output to spend in a PackageTemplate");
824
825                 // If we ever try to aggregate a `HolderHTLCOutput`s with another output type, we'll likely
826                 // end up with an incorrect transaction locktime since the counterparty has included it in
827                 // its HTLC signature. This should never happen unless we decide to aggregate outputs across
828                 // different channel commitments.
829                 #[cfg(debug_assertions)] {
830                         if self.inputs.iter().any(|(_, outp)|
831                                 if let PackageSolvingData::HolderHTLCOutput(outp) = outp {
832                                         outp.preimage.is_some()
833                                 } else {
834                                         false
835                                 }
836                         ) {
837                                 debug_assert_eq!(locktime, 0);
838                         };
839                         for timeout_htlc_expiry in self.inputs.iter().filter_map(|(_, outp)|
840                                 if let PackageSolvingData::HolderHTLCOutput(outp) = outp {
841                                         if outp.preimage.is_none() {
842                                                 Some(outp.cltv_expiry)
843                                         } else { None }
844                                 } else { None }
845                         ) {
846                                 debug_assert_eq!(locktime, timeout_htlc_expiry);
847                         }
848                 }
849
850                 locktime
851         }
852         pub(crate) fn package_weight(&self, destination_script: &Script) -> usize {
853                 let mut inputs_weight = 0;
854                 let mut witnesses_weight = 2; // count segwit flags
855                 for (_, outp) in self.inputs.iter() {
856                         // previous_out_point: 36 bytes ; var_int: 1 byte ; sequence: 4 bytes
857                         inputs_weight += 41 * WITNESS_SCALE_FACTOR;
858                         witnesses_weight += outp.weight();
859                 }
860                 // version: 4 bytes ; count_tx_in: 1 byte ; count_tx_out: 1 byte ; lock_time: 4 bytes
861                 let transaction_weight = 10 * WITNESS_SCALE_FACTOR;
862                 // value: 8 bytes ; var_int: 1 byte ; pk_script: `destination_script.len()`
863                 let output_weight = (8 + 1 + destination_script.len()) * WITNESS_SCALE_FACTOR;
864                 inputs_weight + witnesses_weight + transaction_weight + output_weight
865         }
866         pub(crate) fn construct_malleable_package_with_external_funding<Signer: WriteableEcdsaChannelSigner>(
867                 &self, onchain_handler: &mut OnchainTxHandler<Signer>,
868         ) -> Option<Vec<ExternalHTLCClaim>> {
869                 debug_assert!(self.requires_external_funding());
870                 let mut htlcs: Option<Vec<ExternalHTLCClaim>> = None;
871                 for (previous_output, input) in &self.inputs {
872                         match input {
873                                 PackageSolvingData::HolderHTLCOutput(ref outp) => {
874                                         debug_assert!(outp.channel_type_features.supports_anchors_zero_fee_htlc_tx());
875                                         onchain_handler.generate_external_htlc_claim(&previous_output, &outp.preimage).map(|htlc| {
876                                                 htlcs.get_or_insert_with(|| Vec::with_capacity(self.inputs.len())).push(htlc);
877                                         });
878                                 }
879                                 _ => debug_assert!(false, "Expected HolderHTLCOutputs to not be aggregated with other input types"),
880                         }
881                 }
882                 htlcs
883         }
884         pub(crate) fn finalize_malleable_package<L: Deref, Signer: WriteableEcdsaChannelSigner>(
885                 &self, current_height: u32, onchain_handler: &mut OnchainTxHandler<Signer>, value: u64,
886                 destination_script: Script, logger: &L
887         ) -> Option<Transaction> where L::Target: Logger {
888                 debug_assert!(self.is_malleable());
889                 let mut bumped_tx = Transaction {
890                         version: 2,
891                         lock_time: PackedLockTime(self.package_locktime(current_height)),
892                         input: vec![],
893                         output: vec![TxOut {
894                                 script_pubkey: destination_script,
895                                 value,
896                         }],
897                 };
898                 for (outpoint, _) in self.inputs.iter() {
899                         bumped_tx.input.push(TxIn {
900                                 previous_output: *outpoint,
901                                 script_sig: Script::new(),
902                                 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
903                                 witness: Witness::new(),
904                         });
905                 }
906                 for (i, (outpoint, out)) in self.inputs.iter().enumerate() {
907                         log_debug!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout);
908                         if !out.finalize_input(&mut bumped_tx, i, onchain_handler) { return None; }
909                 }
910                 log_debug!(logger, "Finalized transaction {} ready to broadcast", bumped_tx.txid());
911                 Some(bumped_tx)
912         }
913         pub(crate) fn finalize_untractable_package<L: Deref, Signer: WriteableEcdsaChannelSigner>(
914                 &self, onchain_handler: &mut OnchainTxHandler<Signer>, logger: &L,
915         ) -> Option<Transaction> where L::Target: Logger {
916                 debug_assert!(!self.is_malleable());
917                 if let Some((outpoint, outp)) = self.inputs.first() {
918                         if let Some(final_tx) = outp.get_finalized_tx(outpoint, onchain_handler) {
919                                 log_debug!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout);
920                                 log_debug!(logger, "Finalized transaction {} ready to broadcast", final_tx.txid());
921                                 return Some(final_tx);
922                         }
923                         return None;
924                 } else { panic!("API Error: Package must not be inputs empty"); }
925         }
926         /// In LN, output claimed are time-sensitive, which means we have to spend them before reaching some timelock expiration. At in-channel
927         /// 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
928         /// height that once reached we should generate a new bumped "version" of the claim tx to be sure that we safely claim outputs before
929         /// that our counterparty can do so. If timelock expires soon, height timer is going to be scaled down in consequence to increase
930         /// frequency of the bump and so increase our bets of success.
931         pub(crate) fn get_height_timer(&self, current_height: u32) -> u32 {
932                 if self.soonest_conf_deadline <= current_height + MIDDLE_FREQUENCY_BUMP_INTERVAL {
933                         return current_height + HIGH_FREQUENCY_BUMP_INTERVAL
934                 } else if self.soonest_conf_deadline - current_height <= LOW_FREQUENCY_BUMP_INTERVAL {
935                         return current_height + MIDDLE_FREQUENCY_BUMP_INTERVAL
936                 }
937                 current_height + LOW_FREQUENCY_BUMP_INTERVAL
938         }
939
940         /// Returns value in satoshis to be included as package outgoing output amount and feerate
941         /// which was used to generate the value. Will not return less than `dust_limit_sats` for the
942         /// value.
943         pub(crate) fn compute_package_output<F: Deref, L: Deref>(
944                 &self, predicted_weight: usize, dust_limit_sats: u64, force_feerate_bump: bool,
945                 fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L,
946         ) -> Option<(u64, u64)>
947         where
948                 F::Target: FeeEstimator,
949                 L::Target: Logger,
950         {
951                 debug_assert!(self.malleability == PackageMalleability::Malleable, "The package output is fixed for non-malleable packages");
952                 let input_amounts = self.package_amount();
953                 assert!(dust_limit_sats as i64 > 0, "Output script must be broadcastable/have a 'real' dust limit.");
954                 // If old feerate is 0, first iteration of this claim, use normal fee calculation
955                 if self.feerate_previous != 0 {
956                         if let Some((new_fee, feerate)) = feerate_bump(
957                                 predicted_weight, input_amounts, self.feerate_previous, force_feerate_bump,
958                                 fee_estimator, logger,
959                         ) {
960                                 return Some((cmp::max(input_amounts as i64 - new_fee as i64, dust_limit_sats as i64) as u64, feerate));
961                         }
962                 } else {
963                         if let Some((new_fee, feerate)) = compute_fee_from_spent_amounts(input_amounts, predicted_weight, fee_estimator, logger) {
964                                 return Some((cmp::max(input_amounts as i64 - new_fee as i64, dust_limit_sats as i64) as u64, feerate));
965                         }
966                 }
967                 None
968         }
969
970         /// Computes a feerate based on the given confirmation target. If a previous feerate was used,
971         /// the new feerate is below it, and `force_feerate_bump` is set, we'll use a 25% increase of
972         /// the previous feerate instead of the new feerate.
973         pub(crate) fn compute_package_feerate<F: Deref>(
974                 &self, fee_estimator: &LowerBoundedFeeEstimator<F>, conf_target: ConfirmationTarget,
975                 force_feerate_bump: bool,
976         ) -> u32 where F::Target: FeeEstimator {
977                 let feerate_estimate = fee_estimator.bounded_sat_per_1000_weight(conf_target);
978                 if self.feerate_previous != 0 {
979                         // Use the new fee estimate if it's higher than the one previously used.
980                         if feerate_estimate as u64 > self.feerate_previous {
981                                 feerate_estimate
982                         } else if !force_feerate_bump {
983                                 self.feerate_previous.try_into().unwrap_or(u32::max_value())
984                         } else {
985                                 // Our fee estimate has decreased, but our transaction remains unconfirmed after
986                                 // using our previous fee estimate. This may point to an unreliable fee estimator,
987                                 // so we choose to bump our previous feerate by 25%, making sure we don't use a
988                                 // lower feerate or overpay by a large margin by limiting it to 5x the new fee
989                                 // estimate.
990                                 let previous_feerate = self.feerate_previous.try_into().unwrap_or(u32::max_value());
991                                 let mut new_feerate = previous_feerate.saturating_add(previous_feerate / 4);
992                                 if new_feerate > feerate_estimate * 5 {
993                                         new_feerate = cmp::max(feerate_estimate * 5, previous_feerate);
994                                 }
995                                 new_feerate
996                         }
997                 } else {
998                         feerate_estimate
999                 }
1000         }
1001
1002         /// Determines whether a package contains an input which must have additional external inputs
1003         /// attached to help the spending transaction reach confirmation.
1004         pub(crate) fn requires_external_funding(&self) -> bool {
1005                 self.inputs.iter().find(|input| match input.1 {
1006                         PackageSolvingData::HolderFundingOutput(ref outp) => outp.channel_type_features.supports_anchors_zero_fee_htlc_tx(),
1007                         PackageSolvingData::HolderHTLCOutput(ref outp) => outp.channel_type_features.supports_anchors_zero_fee_htlc_tx(),
1008                         _ => false,
1009                 }).is_some()
1010         }
1011
1012         pub (crate) fn build_package(txid: Txid, vout: u32, input_solving_data: PackageSolvingData, soonest_conf_deadline: u32, height_original: u32) -> Self {
1013                 let (malleability, aggregable) = PackageSolvingData::map_output_type_flags(&input_solving_data);
1014                 let mut inputs = Vec::with_capacity(1);
1015                 inputs.push((BitcoinOutPoint { txid, vout }, input_solving_data));
1016                 PackageTemplate {
1017                         inputs,
1018                         malleability,
1019                         soonest_conf_deadline,
1020                         aggregable,
1021                         feerate_previous: 0,
1022                         height_timer: height_original,
1023                         height_original,
1024                 }
1025         }
1026 }
1027
1028 impl Writeable for PackageTemplate {
1029         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1030                 writer.write_all(&(self.inputs.len() as u64).to_be_bytes())?;
1031                 for (ref outpoint, ref rev_outp) in self.inputs.iter() {
1032                         outpoint.write(writer)?;
1033                         rev_outp.write(writer)?;
1034                 }
1035                 write_tlv_fields!(writer, {
1036                         (0, self.soonest_conf_deadline, required),
1037                         (2, self.feerate_previous, required),
1038                         (4, self.height_original, required),
1039                         (6, self.height_timer, required)
1040                 });
1041                 Ok(())
1042         }
1043 }
1044
1045 impl Readable for PackageTemplate {
1046         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
1047                 let inputs_count = <u64 as Readable>::read(reader)?;
1048                 let mut inputs: Vec<(BitcoinOutPoint, PackageSolvingData)> = Vec::with_capacity(cmp::min(inputs_count as usize, MAX_ALLOC_SIZE / 128));
1049                 for _ in 0..inputs_count {
1050                         let outpoint = Readable::read(reader)?;
1051                         let rev_outp = Readable::read(reader)?;
1052                         inputs.push((outpoint, rev_outp));
1053                 }
1054                 let (malleability, aggregable) = if let Some((_, lead_input)) = inputs.first() {
1055                         PackageSolvingData::map_output_type_flags(&lead_input)
1056                 } else { return Err(DecodeError::InvalidValue); };
1057                 let mut soonest_conf_deadline = 0;
1058                 let mut feerate_previous = 0;
1059                 let mut height_timer = None;
1060                 let mut height_original = 0;
1061                 read_tlv_fields!(reader, {
1062                         (0, soonest_conf_deadline, required),
1063                         (2, feerate_previous, required),
1064                         (4, height_original, required),
1065                         (6, height_timer, option),
1066                 });
1067                 if height_timer.is_none() {
1068                         height_timer = Some(height_original);
1069                 }
1070                 Ok(PackageTemplate {
1071                         inputs,
1072                         malleability,
1073                         soonest_conf_deadline,
1074                         aggregable,
1075                         feerate_previous,
1076                         height_timer: height_timer.unwrap(),
1077                         height_original,
1078                 })
1079         }
1080 }
1081
1082 /// Attempt to propose a bumping fee for a transaction from its spent output's values and predicted
1083 /// weight. We start with the highest priority feerate returned by the node's fee estimator then
1084 /// fall-back to lower priorities until we have enough value available to suck from.
1085 ///
1086 /// If the proposed fee is less than the available spent output's values, we return the proposed
1087 /// fee and the corresponding updated feerate. If the proposed fee is equal or more than the
1088 /// available spent output's values, we return nothing
1089 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)>
1090         where F::Target: FeeEstimator,
1091               L::Target: Logger,
1092 {
1093         let mut updated_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64;
1094         let mut fee = updated_feerate * (predicted_weight as u64) / 1000;
1095         if input_amounts <= fee {
1096                 updated_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Normal) as u64;
1097                 fee = updated_feerate * (predicted_weight as u64) / 1000;
1098                 if input_amounts <= fee {
1099                         updated_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Background) as u64;
1100                         fee = updated_feerate * (predicted_weight as u64) / 1000;
1101                         if input_amounts <= fee {
1102                                 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)",
1103                                         fee, input_amounts);
1104                                 None
1105                         } else {
1106                                 log_warn!(logger, "Used low priority fee for on-chain punishment tx as high priority fee was more than the entire claim balance ({} sat)",
1107                                         input_amounts);
1108                                 Some((fee, updated_feerate))
1109                         }
1110                 } else {
1111                         log_warn!(logger, "Used medium priority fee for on-chain punishment tx as high priority fee was more than the entire claim balance ({} sat)",
1112                                 input_amounts);
1113                         Some((fee, updated_feerate))
1114                 }
1115         } else {
1116                 Some((fee, updated_feerate))
1117         }
1118 }
1119
1120 /// Attempt to propose a bumping fee for a transaction from its spent output's values and predicted
1121 /// weight. If feerates proposed by the fee-estimator have been increasing since last fee-bumping
1122 /// attempt, use them. If `force_feerate_bump` is set, we bump the feerate by 25% of the previous
1123 /// feerate, or just use the previous feerate otherwise. If a feerate bump did happen, we also
1124 /// verify that those bumping heuristics respect BIP125 rules 3) and 4) and if required adjust the
1125 /// new fee to meet the RBF policy requirement.
1126 fn feerate_bump<F: Deref, L: Deref>(
1127         predicted_weight: usize, input_amounts: u64, previous_feerate: u64, force_feerate_bump: bool,
1128         fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L,
1129 ) -> Option<(u64, u64)>
1130 where
1131         F::Target: FeeEstimator,
1132         L::Target: Logger,
1133 {
1134         // If old feerate inferior to actual one given back by Fee Estimator, use it to compute new fee...
1135         let (new_fee, new_feerate) = if let Some((new_fee, new_feerate)) = compute_fee_from_spent_amounts(input_amounts, predicted_weight, fee_estimator, logger) {
1136                 if new_feerate > previous_feerate {
1137                         (new_fee, new_feerate)
1138                 } else if !force_feerate_bump {
1139                         let previous_fee = previous_feerate * (predicted_weight as u64) / 1000;
1140                         (previous_fee, previous_feerate)
1141                 } else {
1142                         // ...else just increase the previous feerate by 25% (because that's a nice number)
1143                         let bumped_feerate = previous_feerate + (previous_feerate / 4);
1144                         let bumped_fee = bumped_feerate * (predicted_weight as u64) / 1000;
1145                         if input_amounts <= bumped_fee {
1146                                 log_warn!(logger, "Can't 25% bump new claiming tx, amount {} is too small", input_amounts);
1147                                 return None;
1148                         }
1149                         (bumped_fee, bumped_feerate)
1150                 }
1151         } else {
1152                 log_warn!(logger, "Can't new-estimation bump new claiming tx, amount {} is too small", input_amounts);
1153                 return None;
1154         };
1155
1156         // Our feerates should never decrease. If it hasn't changed though, we just need to
1157         // rebroadcast/re-sign the previous claim.
1158         debug_assert!(new_feerate >= previous_feerate);
1159         if new_feerate == previous_feerate {
1160                 return Some((new_fee, new_feerate));
1161         }
1162
1163         let previous_fee = previous_feerate * (predicted_weight as u64) / 1000;
1164         let min_relay_fee = MIN_RELAY_FEE_SAT_PER_1000_WEIGHT * (predicted_weight as u64) / 1000;
1165         // BIP 125 Opt-in Full Replace-by-Fee Signaling
1166         //      * 3. The replacement transaction pays an absolute fee of at least the sum paid by the original transactions.
1167         //      * 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.
1168         let new_fee = if new_fee < previous_fee + min_relay_fee {
1169                 new_fee + previous_fee + min_relay_fee - new_fee
1170         } else {
1171                 new_fee
1172         };
1173         Some((new_fee, new_fee * 1000 / (predicted_weight as u64)))
1174 }
1175
1176 #[cfg(test)]
1177 mod tests {
1178         use crate::chain::package::{CounterpartyOfferedHTLCOutput, CounterpartyReceivedHTLCOutput, HolderHTLCOutput, PackageTemplate, PackageSolvingData, RevokedOutput, WEIGHT_REVOKED_OUTPUT, weight_offered_htlc, weight_received_htlc};
1179         use crate::chain::Txid;
1180         use crate::ln::chan_utils::HTLCOutputInCommitment;
1181         use crate::ln::{PaymentPreimage, PaymentHash};
1182
1183         use bitcoin::blockdata::constants::WITNESS_SCALE_FACTOR;
1184         use bitcoin::blockdata::script::Script;
1185         use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
1186
1187         use bitcoin::hashes::hex::FromHex;
1188
1189         use bitcoin::secp256k1::{PublicKey,SecretKey};
1190         use bitcoin::secp256k1::Secp256k1;
1191         use crate::ln::features::ChannelTypeFeatures;
1192
1193         macro_rules! dumb_revk_output {
1194                 ($secp_ctx: expr, $is_counterparty_balance_on_anchors: expr) => {
1195                         {
1196                                 let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
1197                                 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
1198                                 PackageSolvingData::RevokedOutput(RevokedOutput::build(dumb_point, dumb_point, dumb_point, dumb_scalar, 0, 0, $is_counterparty_balance_on_anchors))
1199                         }
1200                 }
1201         }
1202
1203         macro_rules! dumb_counterparty_output {
1204                 ($secp_ctx: expr, $amt: expr, $opt_anchors: expr) => {
1205                         {
1206                                 let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
1207                                 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
1208                                 let hash = PaymentHash([1; 32]);
1209                                 let htlc = HTLCOutputInCommitment { offered: true, amount_msat: $amt, cltv_expiry: 0, payment_hash: hash, transaction_output_index: None };
1210                                 PackageSolvingData::CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput::build(dumb_point, dumb_point, dumb_point, htlc, $opt_anchors))
1211                         }
1212                 }
1213         }
1214
1215         macro_rules! dumb_counterparty_offered_output {
1216                 ($secp_ctx: expr, $amt: expr, $opt_anchors: expr) => {
1217                         {
1218                                 let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
1219                                 let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
1220                                 let hash = PaymentHash([1; 32]);
1221                                 let preimage = PaymentPreimage([2;32]);
1222                                 let htlc = HTLCOutputInCommitment { offered: false, amount_msat: $amt, cltv_expiry: 1000, payment_hash: hash, transaction_output_index: None };
1223                                 PackageSolvingData::CounterpartyOfferedHTLCOutput(CounterpartyOfferedHTLCOutput::build(dumb_point, dumb_point, dumb_point, preimage, htlc, $opt_anchors))
1224                         }
1225                 }
1226         }
1227
1228         macro_rules! dumb_htlc_output {
1229                 () => {
1230                         {
1231                                 let preimage = PaymentPreimage([2;32]);
1232                                 PackageSolvingData::HolderHTLCOutput(HolderHTLCOutput::build_accepted(preimage, 0, ChannelTypeFeatures::only_static_remote_key()))
1233                         }
1234                 }
1235         }
1236
1237         #[test]
1238         #[should_panic]
1239         fn test_package_differing_heights() {
1240                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1241                 let secp_ctx = Secp256k1::new();
1242                 let revk_outp = dumb_revk_output!(secp_ctx, false);
1243
1244                 let mut package_one_hundred = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, 100);
1245                 let package_two_hundred = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, 200);
1246                 package_one_hundred.merge_package(package_two_hundred);
1247         }
1248
1249         #[test]
1250         #[should_panic]
1251         fn test_package_untractable_merge_to() {
1252                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1253                 let secp_ctx = Secp256k1::new();
1254                 let revk_outp = dumb_revk_output!(secp_ctx, false);
1255                 let htlc_outp = dumb_htlc_output!();
1256
1257                 let mut untractable_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, 100);
1258                 let malleable_package = PackageTemplate::build_package(txid, 1, htlc_outp.clone(), 1000, 100);
1259                 untractable_package.merge_package(malleable_package);
1260         }
1261
1262         #[test]
1263         #[should_panic]
1264         fn test_package_untractable_merge_from() {
1265                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1266                 let secp_ctx = Secp256k1::new();
1267                 let htlc_outp = dumb_htlc_output!();
1268                 let revk_outp = dumb_revk_output!(secp_ctx, false);
1269
1270                 let mut malleable_package = PackageTemplate::build_package(txid, 0, htlc_outp.clone(), 1000, 100);
1271                 let untractable_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, 100);
1272                 malleable_package.merge_package(untractable_package);
1273         }
1274
1275         #[test]
1276         #[should_panic]
1277         fn test_package_noaggregation_to() {
1278                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1279                 let secp_ctx = Secp256k1::new();
1280                 let revk_outp = dumb_revk_output!(secp_ctx, false);
1281                 let revk_outp_counterparty_balance = dumb_revk_output!(secp_ctx, true);
1282
1283                 let mut noaggregation_package = PackageTemplate::build_package(txid, 0, revk_outp_counterparty_balance.clone(), 1000, 100);
1284                 let aggregation_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, 100);
1285                 noaggregation_package.merge_package(aggregation_package);
1286         }
1287
1288         #[test]
1289         #[should_panic]
1290         fn test_package_noaggregation_from() {
1291                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1292                 let secp_ctx = Secp256k1::new();
1293                 let revk_outp = dumb_revk_output!(secp_ctx, false);
1294                 let revk_outp_counterparty_balance = dumb_revk_output!(secp_ctx, true);
1295
1296                 let mut aggregation_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, 100);
1297                 let noaggregation_package = PackageTemplate::build_package(txid, 1, revk_outp_counterparty_balance.clone(), 1000, 100);
1298                 aggregation_package.merge_package(noaggregation_package);
1299         }
1300
1301         #[test]
1302         #[should_panic]
1303         fn test_package_empty() {
1304                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1305                 let secp_ctx = Secp256k1::new();
1306                 let revk_outp = dumb_revk_output!(secp_ctx, false);
1307
1308                 let mut empty_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, 100);
1309                 empty_package.inputs = vec![];
1310                 let package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, 100);
1311                 empty_package.merge_package(package);
1312         }
1313
1314         #[test]
1315         #[should_panic]
1316         fn test_package_differing_categories() {
1317                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1318                 let secp_ctx = Secp256k1::new();
1319                 let revk_outp = dumb_revk_output!(secp_ctx, false);
1320                 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 0, ChannelTypeFeatures::only_static_remote_key());
1321
1322                 let mut revoked_package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, 100);
1323                 let counterparty_package = PackageTemplate::build_package(txid, 1, counterparty_outp, 1000, 100);
1324                 revoked_package.merge_package(counterparty_package);
1325         }
1326
1327         #[test]
1328         fn test_package_split_malleable() {
1329                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1330                 let secp_ctx = Secp256k1::new();
1331                 let revk_outp_one = dumb_revk_output!(secp_ctx, false);
1332                 let revk_outp_two = dumb_revk_output!(secp_ctx, false);
1333                 let revk_outp_three = dumb_revk_output!(secp_ctx, false);
1334
1335                 let mut package_one = PackageTemplate::build_package(txid, 0, revk_outp_one, 1000, 100);
1336                 let package_two = PackageTemplate::build_package(txid, 1, revk_outp_two, 1000, 100);
1337                 let package_three = PackageTemplate::build_package(txid, 2, revk_outp_three, 1000, 100);
1338
1339                 package_one.merge_package(package_two);
1340                 package_one.merge_package(package_three);
1341                 assert_eq!(package_one.outpoints().len(), 3);
1342
1343                 if let Some(split_package) = package_one.split_package(&BitcoinOutPoint { txid, vout: 1 }) {
1344                         // Packages attributes should be identical
1345                         assert!(split_package.is_malleable());
1346                         assert_eq!(split_package.soonest_conf_deadline, package_one.soonest_conf_deadline);
1347                         assert_eq!(split_package.aggregable, package_one.aggregable);
1348                         assert_eq!(split_package.feerate_previous, package_one.feerate_previous);
1349                         assert_eq!(split_package.height_timer, package_one.height_timer);
1350                         assert_eq!(split_package.height_original, package_one.height_original);
1351                 } else { panic!(); }
1352                 assert_eq!(package_one.outpoints().len(), 2);
1353         }
1354
1355         #[test]
1356         fn test_package_split_untractable() {
1357                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1358                 let htlc_outp_one = dumb_htlc_output!();
1359
1360                 let mut package_one = PackageTemplate::build_package(txid, 0, htlc_outp_one, 1000, 100);
1361                 let ret_split = package_one.split_package(&BitcoinOutPoint { txid, vout: 0});
1362                 assert!(ret_split.is_none());
1363         }
1364
1365         #[test]
1366         fn test_package_timer() {
1367                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1368                 let secp_ctx = Secp256k1::new();
1369                 let revk_outp = dumb_revk_output!(secp_ctx, false);
1370
1371                 let mut package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, 100);
1372                 assert_eq!(package.timer(), 100);
1373                 package.set_timer(101);
1374                 assert_eq!(package.timer(), 101);
1375         }
1376
1377         #[test]
1378         fn test_package_amounts() {
1379                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1380                 let secp_ctx = Secp256k1::new();
1381                 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 1_000_000, ChannelTypeFeatures::only_static_remote_key());
1382
1383                 let package = PackageTemplate::build_package(txid, 0, counterparty_outp, 1000, 100);
1384                 assert_eq!(package.package_amount(), 1000);
1385         }
1386
1387         #[test]
1388         fn test_package_weight() {
1389                 let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
1390                 let secp_ctx = Secp256k1::new();
1391
1392                 // (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)
1393                 let weight_sans_output = (4 + 4 + 1 + 36 + 4 + 1 + 1 + 8 + 1) * WITNESS_SCALE_FACTOR + 2;
1394
1395                 {
1396                         let revk_outp = dumb_revk_output!(secp_ctx, false);
1397                         let package = PackageTemplate::build_package(txid, 0, revk_outp, 0, 100);
1398                         assert_eq!(package.package_weight(&Script::new()),  weight_sans_output + WEIGHT_REVOKED_OUTPUT as usize);
1399                 }
1400
1401                 {
1402                         for channel_type_features in [ChannelTypeFeatures::only_static_remote_key(), ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()].iter() {
1403                                 let counterparty_outp = dumb_counterparty_output!(secp_ctx, 1_000_000, channel_type_features.clone());
1404                                 let package = PackageTemplate::build_package(txid, 0, counterparty_outp, 1000, 100);
1405                                 assert_eq!(package.package_weight(&Script::new()), weight_sans_output + weight_received_htlc(channel_type_features) as usize);
1406                         }
1407                 }
1408
1409                 {
1410                         for channel_type_features in [ChannelTypeFeatures::only_static_remote_key(), ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()].iter() {
1411                                 let counterparty_outp = dumb_counterparty_offered_output!(secp_ctx, 1_000_000, channel_type_features.clone());
1412                                 let package = PackageTemplate::build_package(txid, 0, counterparty_outp, 1000, 100);
1413                                 assert_eq!(package.package_weight(&Script::new()), weight_sans_output + weight_offered_htlc(channel_type_features) as usize);
1414                         }
1415                 }
1416         }
1417 }