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 use crate::io_extras::sink;
11 use crate::prelude::*;
14 use bitcoin::blockdata::constants::WITNESS_SCALE_FACTOR;
15 use bitcoin::consensus::Encodable;
16 use bitcoin::policy::MAX_STANDARD_TX_WEIGHT;
18 absolute::LockTime as AbsoluteLockTime, OutPoint, Sequence, Transaction, TxIn, TxOut,
21 use crate::chain::chaininterface::fee_for_weight;
22 use crate::events::bump_transaction::{BASE_INPUT_WEIGHT, EMPTY_SCRIPT_SIG_WEIGHT};
23 use crate::ln::channel::TOTAL_BITCOIN_SUPPLY_SATOSHIS;
24 use crate::ln::msgs::SerialId;
25 use crate::ln::{msgs, ChannelId};
26 use crate::sign::EntropySource;
27 use crate::util::ser::TransactionU16LenLimited;
29 /// The number of received `tx_add_input` messages during a negotiation at which point the
30 /// negotiation MUST be failed.
31 const MAX_RECEIVED_TX_ADD_INPUT_COUNT: u16 = 4096;
33 /// The number of received `tx_add_output` messages during a negotiation at which point the
34 /// negotiation MUST be failed.
35 const MAX_RECEIVED_TX_ADD_OUTPUT_COUNT: u16 = 4096;
37 /// The number of inputs or outputs that the state machine can have, before it MUST fail the
39 const MAX_INPUTS_OUTPUTS_COUNT: usize = 252;
42 fn is_for_initiator(&self) -> bool;
43 fn is_for_non_initiator(&self) -> bool;
46 impl SerialIdExt for SerialId {
47 fn is_for_initiator(&self) -> bool {
51 fn is_for_non_initiator(&self) -> bool {
52 !self.is_for_initiator()
56 #[derive(Debug, Clone, PartialEq)]
57 pub enum AbortReason {
58 InvalidStateTransition,
59 UnexpectedCounterpartyMessage,
60 ReceivedTooManyTxAddInputs,
61 ReceivedTooManyTxAddOutputs,
62 IncorrectInputSequenceValue,
63 IncorrectSerialIdParity,
67 ExceededMaximumSatsAllowed,
68 ExceededNumberOfInputsOrOutputs,
73 OutputsValueExceedsInputsValue,
78 pub struct TxInputWithPrevOutput {
84 struct NegotiationContext {
85 holder_is_initiator: bool,
86 received_tx_add_input_count: u16,
87 received_tx_add_output_count: u16,
88 inputs: HashMap<SerialId, TxInputWithPrevOutput>,
89 prevtx_outpoints: HashSet<OutPoint>,
90 outputs: HashMap<SerialId, TxOut>,
91 tx_locktime: AbsoluteLockTime,
92 feerate_sat_per_kw: u32,
95 impl NegotiationContext {
96 fn is_serial_id_valid_for_counterparty(&self, serial_id: &SerialId) -> bool {
97 // A received `SerialId`'s parity must match the role of the counterparty.
98 self.holder_is_initiator == serial_id.is_for_non_initiator()
101 fn total_input_and_output_count(&self) -> usize {
102 self.inputs.len().saturating_add(self.outputs.len())
105 fn counterparty_inputs_contributed(
107 ) -> impl Iterator<Item = &TxInputWithPrevOutput> + Clone {
110 .filter(move |(serial_id, _)| self.is_serial_id_valid_for_counterparty(serial_id))
111 .map(|(_, input_with_prevout)| input_with_prevout)
114 fn counterparty_outputs_contributed(&self) -> impl Iterator<Item = &TxOut> + Clone {
117 .filter(move |(serial_id, _)| self.is_serial_id_valid_for_counterparty(serial_id))
118 .map(|(_, output)| output)
121 fn received_tx_add_input(&mut self, msg: &msgs::TxAddInput) -> Result<(), AbortReason> {
122 // The interactive-txs spec calls for us to fail negotiation if the `prevtx` we receive is
123 // invalid. However, we would not need to account for this explicit negotiation failure
124 // mode here since `PeerManager` would already disconnect the peer if the `prevtx` is
125 // invalid; implicitly ending the negotiation.
127 if !self.is_serial_id_valid_for_counterparty(&msg.serial_id) {
128 // The receiving node:
129 // - MUST fail the negotiation if:
130 // - the `serial_id` has the wrong parity
131 return Err(AbortReason::IncorrectSerialIdParity);
134 self.received_tx_add_input_count += 1;
135 if self.received_tx_add_input_count > MAX_RECEIVED_TX_ADD_INPUT_COUNT {
136 // The receiving node:
137 // - MUST fail the negotiation if:
138 // - if has received 4096 `tx_add_input` messages during this negotiation
139 return Err(AbortReason::ReceivedTooManyTxAddInputs);
142 if msg.sequence >= 0xFFFFFFFE {
143 // The receiving node:
144 // - MUST fail the negotiation if:
145 // - `sequence` is set to `0xFFFFFFFE` or `0xFFFFFFFF`
146 return Err(AbortReason::IncorrectInputSequenceValue);
149 let transaction = msg.prevtx.as_transaction();
150 let txid = transaction.txid();
152 if let Some(tx_out) = transaction.output.get(msg.prevtx_out as usize) {
153 if !tx_out.script_pubkey.is_witness_program() {
154 // The receiving node:
155 // - MUST fail the negotiation if:
156 // - the `scriptPubKey` is not a witness program
157 return Err(AbortReason::PrevTxOutInvalid);
160 if !self.prevtx_outpoints.insert(OutPoint { txid, vout: msg.prevtx_out }) {
161 // The receiving node:
162 // - MUST fail the negotiation if:
163 // - the `prevtx` and `prevtx_vout` are identical to a previously added
164 // (and not removed) input's
165 return Err(AbortReason::PrevTxOutInvalid);
168 // The receiving node:
169 // - MUST fail the negotiation if:
170 // - `prevtx_vout` is greater or equal to the number of outputs on `prevtx`
171 return Err(AbortReason::PrevTxOutInvalid);
174 let prev_out = if let Some(prev_out) = transaction.output.get(msg.prevtx_out as usize) {
177 return Err(AbortReason::PrevTxOutInvalid);
179 match self.inputs.entry(msg.serial_id) {
180 hash_map::Entry::Occupied(_) => {
181 // The receiving node:
182 // - MUST fail the negotiation if:
183 // - the `serial_id` is already included in the transaction
184 Err(AbortReason::DuplicateSerialId)
186 hash_map::Entry::Vacant(entry) => {
187 let prev_outpoint = OutPoint { txid, vout: msg.prevtx_out };
188 entry.insert(TxInputWithPrevOutput {
190 previous_output: prev_outpoint,
191 sequence: Sequence(msg.sequence),
194 prev_output: prev_out,
196 self.prevtx_outpoints.insert(prev_outpoint);
202 fn received_tx_remove_input(&mut self, msg: &msgs::TxRemoveInput) -> Result<(), AbortReason> {
203 if !self.is_serial_id_valid_for_counterparty(&msg.serial_id) {
204 return Err(AbortReason::IncorrectSerialIdParity);
208 .remove(&msg.serial_id)
209 // The receiving node:
210 // - MUST fail the negotiation if:
211 // - the input or output identified by the `serial_id` was not added by the sender
212 // - the `serial_id` does not correspond to a currently added input
213 .ok_or(AbortReason::SerialIdUnknown)
217 fn received_tx_add_output(&mut self, msg: &msgs::TxAddOutput) -> Result<(), AbortReason> {
218 // The receiving node:
219 // - MUST fail the negotiation if:
220 // - the serial_id has the wrong parity
221 if !self.is_serial_id_valid_for_counterparty(&msg.serial_id) {
222 return Err(AbortReason::IncorrectSerialIdParity);
225 self.received_tx_add_output_count += 1;
226 if self.received_tx_add_output_count > MAX_RECEIVED_TX_ADD_OUTPUT_COUNT {
227 // The receiving node:
228 // - MUST fail the negotiation if:
229 // - if has received 4096 `tx_add_output` messages during this negotiation
230 return Err(AbortReason::ReceivedTooManyTxAddOutputs);
233 if msg.sats < msg.script.dust_value().to_sat() {
234 // The receiving node:
235 // - MUST fail the negotiation if:
236 // - the sats amount is less than the dust_limit
237 return Err(AbortReason::BelowDustLimit);
240 // Check that adding this output would not cause the total output value to exceed the total
242 let mut outputs_value: u64 = 0;
243 for output in self.outputs.iter() {
244 outputs_value = outputs_value.saturating_add(output.1.value);
246 if outputs_value.saturating_add(msg.sats) > TOTAL_BITCOIN_SUPPLY_SATOSHIS {
247 // The receiving node:
248 // - MUST fail the negotiation if:
249 // - the sats amount is greater than 2,100,000,000,000,000 (TOTAL_BITCOIN_SUPPLY_SATOSHIS)
250 return Err(AbortReason::ExceededMaximumSatsAllowed);
253 // The receiving node:
254 // - MUST accept P2WSH, P2WPKH, P2TR scripts
255 // - MAY fail the negotiation if script is non-standard
257 // We can actually be a bit looser than the above as only witness version 0 has special
258 // length-based standardness constraints to match similar consensus rules. All witness scripts
259 // with witness versions V1 and up are always considered standard. Yes, the scripts can be
260 // anyone-can-spend-able, but if our counterparty wants to add an output like that then it's none
261 // of our concern really ¯\_(ツ)_/¯
263 // TODO: The last check would be simplified when https://github.com/rust-bitcoin/rust-bitcoin/commit/1656e1a09a1959230e20af90d20789a4a8f0a31b
264 // hits the next release of rust-bitcoin.
265 if !(msg.script.is_v0_p2wpkh()
266 || msg.script.is_v0_p2wsh()
267 || (msg.script.is_witness_program()
268 && msg.script.witness_version().map(|v| v.to_num() >= 1).unwrap_or(false)))
270 return Err(AbortReason::InvalidOutputScript);
273 match self.outputs.entry(msg.serial_id) {
274 hash_map::Entry::Occupied(_) => {
275 // The receiving node:
276 // - MUST fail the negotiation if:
277 // - the `serial_id` is already included in the transaction
278 Err(AbortReason::DuplicateSerialId)
280 hash_map::Entry::Vacant(entry) => {
281 entry.insert(TxOut { value: msg.sats, script_pubkey: msg.script.clone() });
287 fn received_tx_remove_output(&mut self, msg: &msgs::TxRemoveOutput) -> Result<(), AbortReason> {
288 if !self.is_serial_id_valid_for_counterparty(&msg.serial_id) {
289 return Err(AbortReason::IncorrectSerialIdParity);
291 if self.outputs.remove(&msg.serial_id).is_some() {
294 // The receiving node:
295 // - MUST fail the negotiation if:
296 // - the input or output identified by the `serial_id` was not added by the sender
297 // - the `serial_id` does not correspond to a currently added input
298 Err(AbortReason::SerialIdUnknown)
302 fn sent_tx_add_input(&mut self, msg: &msgs::TxAddInput) {
303 let tx = msg.prevtx.as_transaction();
305 previous_output: OutPoint { txid: tx.txid(), vout: msg.prevtx_out },
306 sequence: Sequence(msg.sequence),
309 debug_assert!((msg.prevtx_out as usize) < tx.output.len());
310 let prev_output = &tx.output[msg.prevtx_out as usize];
311 self.prevtx_outpoints.insert(input.previous_output);
314 TxInputWithPrevOutput { input, prev_output: prev_output.clone() },
318 fn sent_tx_add_output(&mut self, msg: &msgs::TxAddOutput) {
320 .insert(msg.serial_id, TxOut { value: msg.sats, script_pubkey: msg.script.clone() });
323 fn sent_tx_remove_input(&mut self, msg: &msgs::TxRemoveInput) {
324 self.inputs.remove(&msg.serial_id);
327 fn sent_tx_remove_output(&mut self, msg: &msgs::TxRemoveOutput) {
328 self.outputs.remove(&msg.serial_id);
331 fn build_transaction(self) -> Result<Transaction, AbortReason> {
332 // The receiving node:
333 // MUST fail the negotiation if:
335 // - the peer's total input satoshis is less than their outputs
336 let mut counterparty_inputs_value: u64 = 0;
337 let mut counterparty_outputs_value: u64 = 0;
338 for input in self.counterparty_inputs_contributed() {
339 counterparty_inputs_value =
340 counterparty_inputs_value.saturating_add(input.prev_output.value);
342 for output in self.counterparty_outputs_contributed() {
343 counterparty_outputs_value = counterparty_outputs_value.saturating_add(output.value);
345 if counterparty_inputs_value < counterparty_outputs_value {
346 return Err(AbortReason::OutputsValueExceedsInputsValue);
349 // - there are more than 252 inputs
350 // - there are more than 252 outputs
351 if self.inputs.len() > MAX_INPUTS_OUTPUTS_COUNT
352 || self.outputs.len() > MAX_INPUTS_OUTPUTS_COUNT
354 return Err(AbortReason::ExceededNumberOfInputsOrOutputs);
357 // TODO: How do we enforce their fees cover the witness without knowing its expected length?
358 const INPUT_WEIGHT: u64 = BASE_INPUT_WEIGHT + EMPTY_SCRIPT_SIG_WEIGHT;
360 // - the peer's paid feerate does not meet or exceed the agreed feerate (based on the minimum fee).
361 let counterparty_output_weight_contributed: u64 = self
362 .counterparty_outputs_contributed()
364 (8 /* value */ + output.script_pubkey.consensus_encode(&mut sink()).unwrap() as u64)
365 * WITNESS_SCALE_FACTOR as u64
368 let counterparty_weight_contributed = counterparty_output_weight_contributed
369 + self.counterparty_inputs_contributed().count() as u64 * INPUT_WEIGHT;
370 let counterparty_fees_contributed =
371 counterparty_inputs_value.saturating_sub(counterparty_outputs_value);
372 let mut required_counterparty_contribution_fee =
373 fee_for_weight(self.feerate_sat_per_kw, counterparty_weight_contributed);
374 if !self.holder_is_initiator {
375 // if is the non-initiator:
376 // - the initiator's fees do not cover the common fields (version, segwit marker + flag,
377 // input count, output count, locktime)
378 let tx_common_fields_weight =
379 (4 /* version */ + 4 /* locktime */ + 1 /* input count */ + 1 /* output count */) *
380 WITNESS_SCALE_FACTOR as u64 + 2 /* segwit marker + flag */;
381 let tx_common_fields_fee =
382 fee_for_weight(self.feerate_sat_per_kw, tx_common_fields_weight);
383 required_counterparty_contribution_fee += tx_common_fields_fee;
385 if counterparty_fees_contributed < required_counterparty_contribution_fee {
386 return Err(AbortReason::InsufficientFees);
389 // Inputs and outputs must be sorted by serial_id
390 let mut inputs = self.inputs.into_iter().collect::<Vec<_>>();
391 let mut outputs = self.outputs.into_iter().collect::<Vec<_>>();
392 inputs.sort_unstable_by_key(|(serial_id, _)| *serial_id);
393 outputs.sort_unstable_by_key(|(serial_id, _)| *serial_id);
395 let tx_to_validate = Transaction {
397 lock_time: self.tx_locktime,
398 input: inputs.into_iter().map(|(_, input)| input.input).collect(),
399 output: outputs.into_iter().map(|(_, output)| output).collect(),
401 if tx_to_validate.weight().to_wu() > MAX_STANDARD_TX_WEIGHT as u64 {
402 return Err(AbortReason::TransactionTooLarge);
409 // The interactive transaction construction protocol allows two peers to collaboratively build a
410 // transaction for broadcast.
412 // The protocol is turn-based, so we define different states here that we store depending on whose
413 // turn it is to send the next message. The states are defined so that their types ensure we only
414 // perform actions (only send messages) via defined state transitions that do not violate the
417 // An example of a full negotiation and associated states follows:
419 // +------------+ +------------------+---- Holder state after message sent/received ----+
420 // | |--(1)- tx_add_input ---->| | SentChangeMsg +
421 // | |<-(2)- tx_complete ------| | ReceivedTxComplete +
422 // | |--(3)- tx_add_output --->| | SentChangeMsg +
423 // | |<-(4)- tx_complete ------| | ReceivedTxComplete +
424 // | |--(5)- tx_add_input ---->| | SentChangeMsg +
425 // | Holder |<-(6)- tx_add_input -----| Counterparty | ReceivedChangeMsg +
426 // | |--(7)- tx_remove_output >| | SentChangeMsg +
427 // | |<-(8)- tx_add_output ----| | ReceivedChangeMsg +
428 // | |--(9)- tx_complete ----->| | SentTxComplete +
429 // | |<-(10) tx_complete ------| | NegotiationComplete +
430 // +------------+ +------------------+--------------------------------------------------+
432 /// Negotiation states that can send & receive `tx_(add|remove)_(input|output)` and `tx_complete`
435 /// Category of states where we have sent some message to the counterparty, and we are waiting for
437 trait SentMsgState: State {
438 fn into_negotiation_context(self) -> NegotiationContext;
441 /// Category of states that our counterparty has put us in after we receive a message from them.
442 trait ReceivedMsgState: State {
443 fn into_negotiation_context(self) -> NegotiationContext;
446 // This macro is a helper for implementing the above state traits for various states subsequently
447 // defined below the macro.
448 macro_rules! define_state {
449 (SENT_MSG_STATE, $state: ident, $doc: expr) => {
450 define_state!($state, NegotiationContext, $doc);
451 impl SentMsgState for $state {
452 fn into_negotiation_context(self) -> NegotiationContext {
457 (RECEIVED_MSG_STATE, $state: ident, $doc: expr) => {
458 define_state!($state, NegotiationContext, $doc);
459 impl ReceivedMsgState for $state {
460 fn into_negotiation_context(self) -> NegotiationContext {
465 ($state: ident, $inner: ident, $doc: expr) => {
468 struct $state($inner);
469 impl State for $state {}
476 "We have sent a message to the counterparty that has affected our negotiation state."
481 "We have sent a `tx_complete` message and are awaiting the counterparty's."
486 "We have received a message from the counterparty that has affected our negotiation state."
491 "We have received a `tx_complete` message and the counterparty is awaiting ours."
493 define_state!(NegotiationComplete, Transaction, "We have exchanged consecutive `tx_complete` messages with the counterparty and the transaction negotiation is complete.");
497 "The negotiation has failed and cannot be continued."
500 type StateTransitionResult<S> = Result<S, AbortReason>;
502 trait StateTransition<NewState: State, TransitionData> {
503 fn transition(self, data: TransitionData) -> StateTransitionResult<NewState>;
506 // This macro helps define the legal transitions between the states above by implementing
507 // the `StateTransition` trait for each of the states that follow this declaration.
508 macro_rules! define_state_transitions {
509 (SENT_MSG_STATE, [$(DATA $data: ty, TRANSITION $transition: ident),+]) => {
511 impl<S: SentMsgState> StateTransition<ReceivedChangeMsg, $data> for S {
512 fn transition(self, data: $data) -> StateTransitionResult<ReceivedChangeMsg> {
513 let mut context = self.into_negotiation_context();
514 context.$transition(data)?;
515 Ok(ReceivedChangeMsg(context))
520 (RECEIVED_MSG_STATE, [$(DATA $data: ty, TRANSITION $transition: ident),+]) => {
522 impl<S: ReceivedMsgState> StateTransition<SentChangeMsg, $data> for S {
523 fn transition(self, data: $data) -> StateTransitionResult<SentChangeMsg> {
524 let mut context = self.into_negotiation_context();
525 context.$transition(data);
526 Ok(SentChangeMsg(context))
531 (TX_COMPLETE, $from_state: ident, $tx_complete_state: ident) => {
532 impl StateTransition<NegotiationComplete, &msgs::TxComplete> for $tx_complete_state {
533 fn transition(self, _data: &msgs::TxComplete) -> StateTransitionResult<NegotiationComplete> {
534 let context = self.into_negotiation_context();
535 let tx = context.build_transaction()?;
536 Ok(NegotiationComplete(tx))
540 impl StateTransition<$tx_complete_state, &msgs::TxComplete> for $from_state {
541 fn transition(self, _data: &msgs::TxComplete) -> StateTransitionResult<$tx_complete_state> {
542 Ok($tx_complete_state(self.into_negotiation_context()))
548 // State transitions when we have sent our counterparty some messages and are waiting for them
550 define_state_transitions!(SENT_MSG_STATE, [
551 DATA &msgs::TxAddInput, TRANSITION received_tx_add_input,
552 DATA &msgs::TxRemoveInput, TRANSITION received_tx_remove_input,
553 DATA &msgs::TxAddOutput, TRANSITION received_tx_add_output,
554 DATA &msgs::TxRemoveOutput, TRANSITION received_tx_remove_output
556 // State transitions when we have received some messages from our counterparty and we should
558 define_state_transitions!(RECEIVED_MSG_STATE, [
559 DATA &msgs::TxAddInput, TRANSITION sent_tx_add_input,
560 DATA &msgs::TxRemoveInput, TRANSITION sent_tx_remove_input,
561 DATA &msgs::TxAddOutput, TRANSITION sent_tx_add_output,
562 DATA &msgs::TxRemoveOutput, TRANSITION sent_tx_remove_output
564 define_state_transitions!(TX_COMPLETE, SentChangeMsg, ReceivedTxComplete);
565 define_state_transitions!(TX_COMPLETE, ReceivedChangeMsg, SentTxComplete);
570 SentChangeMsg(SentChangeMsg),
571 ReceivedChangeMsg(ReceivedChangeMsg),
572 SentTxComplete(SentTxComplete),
573 ReceivedTxComplete(ReceivedTxComplete),
574 NegotiationComplete(NegotiationComplete),
575 NegotiationAborted(NegotiationAborted),
578 impl Default for StateMachine {
579 fn default() -> Self {
584 // The `StateMachine` internally executes the actual transition between two states and keeps
585 // track of the current state. This macro defines _how_ those state transitions happen to
586 // update the internal state.
587 macro_rules! define_state_machine_transitions {
588 ($transition: ident, $msg: ty, [$(FROM $from_state: ident, TO $to_state: ident),+]) => {
589 fn $transition(self, msg: $msg) -> StateMachine {
592 Self::$from_state(s) => match s.transition(msg) {
593 Ok(new_state) => StateMachine::$to_state(new_state),
594 Err(abort_reason) => StateMachine::NegotiationAborted(NegotiationAborted(abort_reason)),
597 _ => StateMachine::NegotiationAborted(NegotiationAborted(AbortReason::UnexpectedCounterpartyMessage)),
604 fn new(feerate_sat_per_kw: u32, is_initiator: bool, tx_locktime: AbsoluteLockTime) -> Self {
605 let context = NegotiationContext {
607 holder_is_initiator: is_initiator,
608 received_tx_add_input_count: 0,
609 received_tx_add_output_count: 0,
610 inputs: new_hash_map(),
611 prevtx_outpoints: new_hash_set(),
612 outputs: new_hash_map(),
616 Self::ReceivedChangeMsg(ReceivedChangeMsg(context))
618 Self::SentChangeMsg(SentChangeMsg(context))
623 define_state_machine_transitions!(sent_tx_add_input, &msgs::TxAddInput, [
624 FROM ReceivedChangeMsg, TO SentChangeMsg,
625 FROM ReceivedTxComplete, TO SentChangeMsg
627 define_state_machine_transitions!(received_tx_add_input, &msgs::TxAddInput, [
628 FROM SentChangeMsg, TO ReceivedChangeMsg,
629 FROM SentTxComplete, TO ReceivedChangeMsg
633 define_state_machine_transitions!(sent_tx_add_output, &msgs::TxAddOutput, [
634 FROM ReceivedChangeMsg, TO SentChangeMsg,
635 FROM ReceivedTxComplete, TO SentChangeMsg
637 define_state_machine_transitions!(received_tx_add_output, &msgs::TxAddOutput, [
638 FROM SentChangeMsg, TO ReceivedChangeMsg,
639 FROM SentTxComplete, TO ReceivedChangeMsg
643 define_state_machine_transitions!(sent_tx_remove_input, &msgs::TxRemoveInput, [
644 FROM ReceivedChangeMsg, TO SentChangeMsg,
645 FROM ReceivedTxComplete, TO SentChangeMsg
647 define_state_machine_transitions!(received_tx_remove_input, &msgs::TxRemoveInput, [
648 FROM SentChangeMsg, TO ReceivedChangeMsg,
649 FROM SentTxComplete, TO ReceivedChangeMsg
653 define_state_machine_transitions!(sent_tx_remove_output, &msgs::TxRemoveOutput, [
654 FROM ReceivedChangeMsg, TO SentChangeMsg,
655 FROM ReceivedTxComplete, TO SentChangeMsg
657 define_state_machine_transitions!(received_tx_remove_output, &msgs::TxRemoveOutput, [
658 FROM SentChangeMsg, TO ReceivedChangeMsg,
659 FROM SentTxComplete, TO ReceivedChangeMsg
663 define_state_machine_transitions!(sent_tx_complete, &msgs::TxComplete, [
664 FROM ReceivedChangeMsg, TO SentTxComplete,
665 FROM ReceivedTxComplete, TO NegotiationComplete
667 define_state_machine_transitions!(received_tx_complete, &msgs::TxComplete, [
668 FROM SentChangeMsg, TO ReceivedTxComplete,
669 FROM SentTxComplete, TO NegotiationComplete
673 pub struct InteractiveTxConstructor {
674 state_machine: StateMachine,
675 channel_id: ChannelId,
676 inputs_to_contribute: Vec<(SerialId, TxIn, TransactionU16LenLimited)>,
677 outputs_to_contribute: Vec<(SerialId, TxOut)>,
680 pub enum InteractiveTxMessageSend {
681 TxAddInput(msgs::TxAddInput),
682 TxAddOutput(msgs::TxAddOutput),
683 TxComplete(msgs::TxComplete),
686 // This macro executes a state machine transition based on a provided action.
687 macro_rules! do_state_transition {
688 ($self: ident, $transition: ident, $msg: expr) => {{
689 let state_machine = core::mem::take(&mut $self.state_machine);
690 $self.state_machine = state_machine.$transition($msg);
691 match &$self.state_machine {
692 StateMachine::NegotiationAborted(state) => Err(state.0.clone()),
698 fn generate_holder_serial_id<ES: Deref>(entropy_source: &ES, is_initiator: bool) -> SerialId
700 ES::Target: EntropySource,
702 let rand_bytes = entropy_source.get_secure_random_bytes();
703 let mut serial_id_bytes = [0u8; 8];
704 serial_id_bytes.copy_from_slice(&rand_bytes[..8]);
705 let mut serial_id = u64::from_be_bytes(serial_id_bytes);
706 if serial_id.is_for_initiator() != is_initiator {
712 pub enum HandleTxCompleteValue {
713 SendTxMessage(InteractiveTxMessageSend),
714 SendTxComplete(InteractiveTxMessageSend, Transaction),
715 NegotiationComplete(Transaction),
718 impl InteractiveTxConstructor {
719 /// Instantiates a new `InteractiveTxConstructor`.
721 /// A tuple is returned containing the newly instantiate `InteractiveTxConstructor` and optionally
722 /// an initial wrapped `Tx_` message which the holder needs to send to the counterparty.
723 pub fn new<ES: Deref>(
724 entropy_source: &ES, channel_id: ChannelId, feerate_sat_per_kw: u32, is_initiator: bool,
725 funding_tx_locktime: AbsoluteLockTime,
726 inputs_to_contribute: Vec<(TxIn, TransactionU16LenLimited)>,
727 outputs_to_contribute: Vec<TxOut>,
728 ) -> (Self, Option<InteractiveTxMessageSend>)
730 ES::Target: EntropySource,
733 StateMachine::new(feerate_sat_per_kw, is_initiator, funding_tx_locktime);
734 let mut inputs_to_contribute: Vec<(SerialId, TxIn, TransactionU16LenLimited)> =
738 let serial_id = generate_holder_serial_id(entropy_source, is_initiator);
739 (serial_id, input, tx)
742 // We'll sort by the randomly generated serial IDs, effectively shuffling the order of the inputs
743 // as the user passed them to us to avoid leaking any potential categorization of transactions
744 // before we pass any of the inputs to the counterparty.
745 inputs_to_contribute.sort_unstable_by_key(|(serial_id, _, _)| *serial_id);
746 let mut outputs_to_contribute: Vec<(SerialId, TxOut)> = outputs_to_contribute
749 let serial_id = generate_holder_serial_id(entropy_source, is_initiator);
753 // In the same manner and for the same rationale as the inputs above, we'll shuffle the outputs.
754 outputs_to_contribute.sort_unstable_by_key(|(serial_id, _)| *serial_id);
755 let mut constructor =
756 Self { state_machine, channel_id, inputs_to_contribute, outputs_to_contribute };
757 let message_send = if is_initiator {
758 match constructor.maybe_send_message() {
759 Ok(msg_send) => Some(msg_send),
763 "We should always be able to start our state machine successfully"
771 (constructor, message_send)
774 fn maybe_send_message(&mut self) -> Result<InteractiveTxMessageSend, AbortReason> {
775 // We first attempt to send inputs we want to add, then outputs. Once we are done sending
776 // them both, then we always send tx_complete.
777 if let Some((serial_id, input, prevtx)) = self.inputs_to_contribute.pop() {
778 let msg = msgs::TxAddInput {
779 channel_id: self.channel_id,
782 prevtx_out: input.previous_output.vout,
783 sequence: input.sequence.to_consensus_u32(),
785 do_state_transition!(self, sent_tx_add_input, &msg)?;
786 Ok(InteractiveTxMessageSend::TxAddInput(msg))
787 } else if let Some((serial_id, output)) = self.outputs_to_contribute.pop() {
788 let msg = msgs::TxAddOutput {
789 channel_id: self.channel_id,
792 script: output.script_pubkey,
794 do_state_transition!(self, sent_tx_add_output, &msg)?;
795 Ok(InteractiveTxMessageSend::TxAddOutput(msg))
797 let msg = msgs::TxComplete { channel_id: self.channel_id };
798 do_state_transition!(self, sent_tx_complete, &msg)?;
799 Ok(InteractiveTxMessageSend::TxComplete(msg))
803 pub fn handle_tx_add_input(
804 &mut self, msg: &msgs::TxAddInput,
805 ) -> Result<InteractiveTxMessageSend, AbortReason> {
806 do_state_transition!(self, received_tx_add_input, msg)?;
807 self.maybe_send_message()
810 pub fn handle_tx_remove_input(
811 &mut self, msg: &msgs::TxRemoveInput,
812 ) -> Result<InteractiveTxMessageSend, AbortReason> {
813 do_state_transition!(self, received_tx_remove_input, msg)?;
814 self.maybe_send_message()
817 pub fn handle_tx_add_output(
818 &mut self, msg: &msgs::TxAddOutput,
819 ) -> Result<InteractiveTxMessageSend, AbortReason> {
820 do_state_transition!(self, received_tx_add_output, msg)?;
821 self.maybe_send_message()
824 pub fn handle_tx_remove_output(
825 &mut self, msg: &msgs::TxRemoveOutput,
826 ) -> Result<InteractiveTxMessageSend, AbortReason> {
827 do_state_transition!(self, received_tx_remove_output, msg)?;
828 self.maybe_send_message()
831 pub fn handle_tx_complete(
832 &mut self, msg: &msgs::TxComplete,
833 ) -> Result<HandleTxCompleteValue, AbortReason> {
834 do_state_transition!(self, received_tx_complete, msg)?;
835 match &self.state_machine {
836 StateMachine::ReceivedTxComplete(_) => {
837 let msg_send = self.maybe_send_message()?;
838 match &self.state_machine {
839 StateMachine::NegotiationComplete(s) => {
840 Ok(HandleTxCompleteValue::SendTxComplete(msg_send, s.0.clone()))
842 StateMachine::SentChangeMsg(_) => {
843 Ok(HandleTxCompleteValue::SendTxMessage(msg_send))
844 }, // We either had an input or output to contribute.
846 debug_assert!(false, "We cannot transition to any other states after receiving `tx_complete` and responding");
847 Err(AbortReason::InvalidStateTransition)
851 StateMachine::NegotiationComplete(s) => {
852 Ok(HandleTxCompleteValue::NegotiationComplete(s.0.clone()))
857 "We cannot transition to any other states after receiving `tx_complete`"
859 Err(AbortReason::InvalidStateTransition)
867 use crate::chain::chaininterface::FEERATE_FLOOR_SATS_PER_KW;
868 use crate::ln::channel::TOTAL_BITCOIN_SUPPLY_SATOSHIS;
869 use crate::ln::interactivetxs::{
870 generate_holder_serial_id, AbortReason, HandleTxCompleteValue, InteractiveTxConstructor,
871 InteractiveTxMessageSend, MAX_INPUTS_OUTPUTS_COUNT, MAX_RECEIVED_TX_ADD_INPUT_COUNT,
872 MAX_RECEIVED_TX_ADD_OUTPUT_COUNT,
874 use crate::ln::ChannelId;
875 use crate::sign::EntropySource;
876 use crate::util::atomic_counter::AtomicCounter;
877 use crate::util::ser::TransactionU16LenLimited;
878 use bitcoin::blockdata::opcodes;
879 use bitcoin::blockdata::script::Builder;
881 absolute::LockTime as AbsoluteLockTime, OutPoint, Sequence, Transaction, TxIn, TxOut,
883 use core::ops::Deref;
885 // A simple entropy source that works based on an atomic counter.
886 struct TestEntropySource(AtomicCounter);
887 impl EntropySource for TestEntropySource {
888 fn get_secure_random_bytes(&self) -> [u8; 32] {
889 let mut res = [0u8; 32];
890 let increment = self.0.get_increment();
892 // Rotate the increment value by 'i' bits to the right, to avoid clashes
893 // when `generate_local_serial_id` does a parity flip on consecutive calls for the
895 let rotated_increment = increment.rotate_right(i as u32);
896 res[i] = (rotated_increment & 0xff) as u8;
902 // An entropy source that deliberately returns you the same seed every time. We use this
903 // to test if the constructor would catch inputs/outputs that are attempting to be added
904 // with duplicate serial ids.
905 struct DuplicateEntropySource;
906 impl EntropySource for DuplicateEntropySource {
907 fn get_secure_random_bytes(&self) -> [u8; 32] {
908 let mut res = [0u8; 32];
910 res[0..8].copy_from_slice(&count.to_be_bytes());
915 #[derive(Debug, PartialEq, Eq)]
919 // Some error values are only checked at the end of the negotiation and are not easy to attribute
920 // to a particular party. Both parties would indicate an `AbortReason` in this case.
921 // e.g. Exceeded max inputs and outputs after negotiation.
926 inputs_a: Vec<(TxIn, TransactionU16LenLimited)>,
927 outputs_a: Vec<TxOut>,
928 inputs_b: Vec<(TxIn, TransactionU16LenLimited)>,
929 outputs_b: Vec<TxOut>,
930 expect_error: Option<(AbortReason, ErrorCulprit)>,
933 fn do_test_interactive_tx_constructor(session: TestSession) {
934 let entropy_source = TestEntropySource(AtomicCounter::new());
935 do_test_interactive_tx_constructor_internal(session, &&entropy_source);
938 fn do_test_interactive_tx_constructor_with_entropy_source<ES: Deref>(
939 session: TestSession, entropy_source: ES,
941 ES::Target: EntropySource,
943 do_test_interactive_tx_constructor_internal(session, &entropy_source);
946 fn do_test_interactive_tx_constructor_internal<ES: Deref>(
947 session: TestSession, entropy_source: &ES,
949 ES::Target: EntropySource,
951 let channel_id = ChannelId(entropy_source.get_secure_random_bytes());
952 let tx_locktime = AbsoluteLockTime::from_height(1337).unwrap();
954 let (mut constructor_a, first_message_a) = InteractiveTxConstructor::new(
957 FEERATE_FLOOR_SATS_PER_KW * 10,
963 let (mut constructor_b, first_message_b) = InteractiveTxConstructor::new(
966 FEERATE_FLOOR_SATS_PER_KW * 10,
973 let handle_message_send =
974 |msg: InteractiveTxMessageSend, for_constructor: &mut InteractiveTxConstructor| {
976 InteractiveTxMessageSend::TxAddInput(msg) => for_constructor
977 .handle_tx_add_input(&msg)
978 .map(|msg_send| (Some(msg_send), None)),
979 InteractiveTxMessageSend::TxAddOutput(msg) => for_constructor
980 .handle_tx_add_output(&msg)
981 .map(|msg_send| (Some(msg_send), None)),
982 InteractiveTxMessageSend::TxComplete(msg) => {
983 for_constructor.handle_tx_complete(&msg).map(|value| match value {
984 HandleTxCompleteValue::SendTxMessage(msg_send) => {
985 (Some(msg_send), None)
987 HandleTxCompleteValue::SendTxComplete(msg_send, tx) => {
988 (Some(msg_send), Some(tx))
990 HandleTxCompleteValue::NegotiationComplete(tx) => (None, Some(tx)),
996 assert!(first_message_b.is_none());
997 let mut message_send_a = first_message_a;
998 let mut message_send_b = None;
999 let mut final_tx_a = None;
1000 let mut final_tx_b = None;
1001 while final_tx_a.is_none() || final_tx_b.is_none() {
1002 if let Some(message_send_a) = message_send_a.take() {
1003 match handle_message_send(message_send_a, &mut constructor_b) {
1004 Ok((msg_send, final_tx)) => {
1005 message_send_b = msg_send;
1006 final_tx_b = final_tx;
1008 Err(abort_reason) => {
1009 let error_culprit = match abort_reason {
1010 AbortReason::ExceededNumberOfInputsOrOutputs => {
1011 ErrorCulprit::Indeterminate
1013 _ => ErrorCulprit::NodeA,
1015 assert_eq!(Some((abort_reason, error_culprit)), session.expect_error);
1016 assert!(message_send_b.is_none());
1021 if let Some(message_send_b) = message_send_b.take() {
1022 match handle_message_send(message_send_b, &mut constructor_a) {
1023 Ok((msg_send, final_tx)) => {
1024 message_send_a = msg_send;
1025 final_tx_a = final_tx;
1027 Err(abort_reason) => {
1028 let error_culprit = match abort_reason {
1029 AbortReason::ExceededNumberOfInputsOrOutputs => {
1030 ErrorCulprit::Indeterminate
1032 _ => ErrorCulprit::NodeB,
1034 assert_eq!(Some((abort_reason, error_culprit)), session.expect_error);
1035 assert!(message_send_a.is_none());
1041 assert!(message_send_a.is_none());
1042 assert!(message_send_b.is_none());
1043 assert_eq!(final_tx_a, final_tx_b);
1044 assert!(session.expect_error.is_none());
1047 fn generate_tx(values: &[u64]) -> Transaction {
1048 generate_tx_with_locktime(values, 1337)
1051 fn generate_tx_with_locktime(values: &[u64], locktime: u32) -> Transaction {
1054 lock_time: AbsoluteLockTime::from_height(locktime).unwrap(),
1055 input: vec![TxIn { ..Default::default() }],
1058 .map(|value| TxOut {
1060 script_pubkey: Builder::new()
1061 .push_opcode(opcodes::OP_TRUE)
1069 fn generate_inputs(values: &[u64]) -> Vec<(TxIn, TransactionU16LenLimited)> {
1070 let tx = generate_tx(values);
1071 let txid = tx.txid();
1077 previous_output: OutPoint { txid, vout: idx as u32 },
1078 script_sig: Default::default(),
1079 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
1080 witness: Default::default(),
1082 (input, TransactionU16LenLimited::new(tx.clone()).unwrap())
1087 fn generate_outputs(values: &[u64]) -> Vec<TxOut> {
1090 .map(|value| TxOut {
1092 script_pubkey: Builder::new()
1093 .push_opcode(opcodes::OP_TRUE)
1100 fn generate_fixed_number_of_inputs(count: u16) -> Vec<(TxIn, TransactionU16LenLimited)> {
1101 // Generate transactions with a total `count` number of outputs such that no transaction has a
1102 // serialized length greater than u16::MAX.
1103 let max_outputs_per_prevtx = 1_500;
1104 let mut remaining = count;
1105 let mut inputs: Vec<(TxIn, TransactionU16LenLimited)> = Vec::with_capacity(count as usize);
1107 while remaining > 0 {
1108 let tx_output_count = remaining.min(max_outputs_per_prevtx);
1109 remaining -= tx_output_count;
1111 // Use unique locktime for each tx so outpoints are different across transactions
1112 let tx = generate_tx_with_locktime(
1113 &vec![1_000_000; tx_output_count as usize],
1114 (1337 + remaining).into(),
1116 let txid = tx.txid();
1118 let mut temp: Vec<(TxIn, TransactionU16LenLimited)> = tx
1124 previous_output: OutPoint { txid, vout: idx as u32 },
1125 script_sig: Default::default(),
1126 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
1127 witness: Default::default(),
1129 (input, TransactionU16LenLimited::new(tx.clone()).unwrap())
1133 inputs.append(&mut temp);
1139 fn generate_fixed_number_of_outputs(count: u16) -> Vec<TxOut> {
1140 // Set a constant value for each TxOut
1141 generate_outputs(&vec![1_000_000; count as usize])
1144 fn generate_non_witness_output(value: u64) -> TxOut {
1147 script_pubkey: Builder::new().push_opcode(opcodes::OP_TRUE).into_script().to_p2sh(),
1152 fn test_interactive_tx_constructor() {
1153 // No contributions.
1154 do_test_interactive_tx_constructor(TestSession {
1159 expect_error: Some((AbortReason::InsufficientFees, ErrorCulprit::NodeA)),
1161 // Single contribution, no initiator inputs.
1162 do_test_interactive_tx_constructor(TestSession {
1164 outputs_a: generate_outputs(&[1_000_000]),
1167 expect_error: Some((AbortReason::OutputsValueExceedsInputsValue, ErrorCulprit::NodeA)),
1169 // Single contribution, no initiator outputs.
1170 do_test_interactive_tx_constructor(TestSession {
1171 inputs_a: generate_inputs(&[1_000_000]),
1177 // Single contribution, insufficient fees.
1178 do_test_interactive_tx_constructor(TestSession {
1179 inputs_a: generate_inputs(&[1_000_000]),
1180 outputs_a: generate_outputs(&[1_000_000]),
1183 expect_error: Some((AbortReason::InsufficientFees, ErrorCulprit::NodeA)),
1185 // Initiator contributes sufficient fees, but non-initiator does not.
1186 do_test_interactive_tx_constructor(TestSession {
1187 inputs_a: generate_inputs(&[1_000_000]),
1189 inputs_b: generate_inputs(&[100_000]),
1190 outputs_b: generate_outputs(&[100_000]),
1191 expect_error: Some((AbortReason::InsufficientFees, ErrorCulprit::NodeB)),
1193 // Multi-input-output contributions from both sides.
1194 do_test_interactive_tx_constructor(TestSession {
1195 inputs_a: generate_inputs(&[1_000_000, 1_000_000]),
1196 outputs_a: generate_outputs(&[1_000_000, 200_000]),
1197 inputs_b: generate_inputs(&[1_000_000, 500_000]),
1198 outputs_b: generate_outputs(&[1_000_000, 400_000]),
1202 // Prevout from initiator is not a witness program
1203 let non_segwit_output_tx = {
1204 let mut tx = generate_tx(&[1_000_000]);
1205 tx.output.push(TxOut {
1206 script_pubkey: Builder::new()
1207 .push_opcode(opcodes::all::OP_RETURN)
1210 ..Default::default()
1213 TransactionU16LenLimited::new(tx).unwrap()
1215 let non_segwit_input = TxIn {
1216 previous_output: OutPoint {
1217 txid: non_segwit_output_tx.as_transaction().txid(),
1220 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
1221 ..Default::default()
1223 do_test_interactive_tx_constructor(TestSession {
1224 inputs_a: vec![(non_segwit_input, non_segwit_output_tx)],
1228 expect_error: Some((AbortReason::PrevTxOutInvalid, ErrorCulprit::NodeA)),
1231 // Invalid input sequence from initiator.
1232 let tx = TransactionU16LenLimited::new(generate_tx(&[1_000_000])).unwrap();
1233 let invalid_sequence_input = TxIn {
1234 previous_output: OutPoint { txid: tx.as_transaction().txid(), vout: 0 },
1235 ..Default::default()
1237 do_test_interactive_tx_constructor(TestSession {
1238 inputs_a: vec![(invalid_sequence_input, tx.clone())],
1239 outputs_a: generate_outputs(&[1_000_000]),
1242 expect_error: Some((AbortReason::IncorrectInputSequenceValue, ErrorCulprit::NodeA)),
1244 // Duplicate prevout from initiator.
1245 let duplicate_input = TxIn {
1246 previous_output: OutPoint { txid: tx.as_transaction().txid(), vout: 0 },
1247 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
1248 ..Default::default()
1250 do_test_interactive_tx_constructor(TestSession {
1251 inputs_a: vec![(duplicate_input.clone(), tx.clone()), (duplicate_input, tx.clone())],
1252 outputs_a: generate_outputs(&[1_000_000]),
1255 expect_error: Some((AbortReason::PrevTxOutInvalid, ErrorCulprit::NodeA)),
1257 // Non-initiator uses same prevout as initiator.
1258 let duplicate_input = TxIn {
1259 previous_output: OutPoint { txid: tx.as_transaction().txid(), vout: 0 },
1260 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
1261 ..Default::default()
1263 do_test_interactive_tx_constructor(TestSession {
1264 inputs_a: vec![(duplicate_input.clone(), tx.clone())],
1265 outputs_a: generate_outputs(&[1_000_000]),
1266 inputs_b: vec![(duplicate_input.clone(), tx.clone())],
1268 expect_error: Some((AbortReason::PrevTxOutInvalid, ErrorCulprit::NodeB)),
1270 // Initiator sends too many TxAddInputs
1271 do_test_interactive_tx_constructor(TestSession {
1272 inputs_a: generate_fixed_number_of_inputs(MAX_RECEIVED_TX_ADD_INPUT_COUNT + 1),
1276 expect_error: Some((AbortReason::ReceivedTooManyTxAddInputs, ErrorCulprit::NodeA)),
1278 // Attempt to queue up two inputs with duplicate serial ids. We use a deliberately bad
1279 // entropy source, `DuplicateEntropySource` to simulate this.
1280 do_test_interactive_tx_constructor_with_entropy_source(
1282 inputs_a: generate_fixed_number_of_inputs(2),
1286 expect_error: Some((AbortReason::DuplicateSerialId, ErrorCulprit::NodeA)),
1288 &DuplicateEntropySource,
1290 // Initiator sends too many TxAddOutputs.
1291 do_test_interactive_tx_constructor(TestSession {
1293 outputs_a: generate_fixed_number_of_outputs(MAX_RECEIVED_TX_ADD_OUTPUT_COUNT + 1),
1296 expect_error: Some((AbortReason::ReceivedTooManyTxAddOutputs, ErrorCulprit::NodeA)),
1298 // Initiator sends an output below dust value.
1299 do_test_interactive_tx_constructor(TestSession {
1301 outputs_a: generate_outputs(&[1]),
1304 expect_error: Some((AbortReason::BelowDustLimit, ErrorCulprit::NodeA)),
1306 // Initiator sends an output above maximum sats allowed.
1307 do_test_interactive_tx_constructor(TestSession {
1309 outputs_a: generate_outputs(&[TOTAL_BITCOIN_SUPPLY_SATOSHIS + 1]),
1312 expect_error: Some((AbortReason::ExceededMaximumSatsAllowed, ErrorCulprit::NodeA)),
1314 // Initiator sends an output without a witness program.
1315 do_test_interactive_tx_constructor(TestSession {
1317 outputs_a: vec![generate_non_witness_output(1_000_000)],
1320 expect_error: Some((AbortReason::InvalidOutputScript, ErrorCulprit::NodeA)),
1322 // Attempt to queue up two outputs with duplicate serial ids. We use a deliberately bad
1323 // entropy source, `DuplicateEntropySource` to simulate this.
1324 do_test_interactive_tx_constructor_with_entropy_source(
1327 outputs_a: generate_fixed_number_of_outputs(2),
1330 expect_error: Some((AbortReason::DuplicateSerialId, ErrorCulprit::NodeA)),
1332 &DuplicateEntropySource,
1335 // Peer contributed more output value than inputs
1336 do_test_interactive_tx_constructor(TestSession {
1337 inputs_a: generate_inputs(&[100_000]),
1338 outputs_a: generate_outputs(&[1_000_000]),
1341 expect_error: Some((AbortReason::OutputsValueExceedsInputsValue, ErrorCulprit::NodeA)),
1344 // Peer contributed more than allowed number of inputs.
1345 do_test_interactive_tx_constructor(TestSession {
1346 inputs_a: generate_fixed_number_of_inputs(MAX_INPUTS_OUTPUTS_COUNT as u16 + 1),
1350 expect_error: Some((
1351 AbortReason::ExceededNumberOfInputsOrOutputs,
1352 ErrorCulprit::Indeterminate,
1355 // Peer contributed more than allowed number of outputs.
1356 do_test_interactive_tx_constructor(TestSession {
1357 inputs_a: generate_inputs(&[TOTAL_BITCOIN_SUPPLY_SATOSHIS]),
1358 outputs_a: generate_fixed_number_of_outputs(MAX_INPUTS_OUTPUTS_COUNT as u16 + 1),
1361 expect_error: Some((
1362 AbortReason::ExceededNumberOfInputsOrOutputs,
1363 ErrorCulprit::Indeterminate,
1369 fn test_generate_local_serial_id() {
1370 let entropy_source = TestEntropySource(AtomicCounter::new());
1372 // Initiators should have even serial id, non-initiators should have odd serial id.
1373 assert_eq!(generate_holder_serial_id(&&entropy_source, true) % 2, 0);
1374 assert_eq!(generate_holder_serial_id(&&entropy_source, false) % 2, 1)