Add manual testing for accepting dual-funded channels

dunxen · dunxen · commit 7b577bf883b1 · 2024-10-22T16:29:00.000+02:00
diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
@@ -3981,6 +3981,20 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider {
 			_ => todo!(),
 		}
 	}
+
+	#[cfg(test)]
+	pub fn get_initial_counterparty_commitment_signature_for_test<L: Deref>(
+		&mut self, logger: &L, channel_transaction_parameters: ChannelTransactionParameters,
+		counterparty_cur_commitment_point_override: PublicKey,
+	) -> Result<Signature, ChannelError>
+	where
+		SP::Target: SignerProvider,
+		L::Target: Logger
+	{
+		self.counterparty_cur_commitment_point = Some(counterparty_cur_commitment_point_override);
+		self.channel_transaction_parameters = channel_transaction_parameters;
+		self.get_initial_counterparty_commitment_signature(logger)
+	}
 }
 
 // Internal utility functions for channels
@@ -8824,7 +8838,7 @@ impl<SP: Deref> InboundV2Channel<SP> where SP::Target: SignerProvider {
 				is_initiator: false,
 			    inputs_to_contribute: dual_funding_context.our_funding_inputs.clone(),
 			    outputs_to_contribute: Vec::new(),
-			    expected_remote_shared_funding_output: Some((context.get_funding_redeemscript(), context.channel_value_satoshis)),
+			    expected_remote_shared_funding_output: Some((context.get_funding_redeemscript().to_p2wsh(), context.channel_value_satoshis)),
 			}
 		).map_err(|_| ChannelError::Close((
 			"V2 channel rejected due to sender error".into(),
diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs
@@ -13514,20 +13514,24 @@ mod tests {
 	use bitcoin::hashes::sha256::Hash as Sha256;
 	use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
 	use core::sync::atomic::Ordering;
+	use crate::chain::chaininterface::{ConfirmationTarget, FeeEstimator, LowerBoundedFeeEstimator};
 	use crate::events::{Event, HTLCDestination, MessageSendEvent, MessageSendEventsProvider, ClosureReason};
 	use crate::ln::types::ChannelId;
 	use crate::types::payment::{PaymentPreimage, PaymentHash, PaymentSecret};
+	use crate::ln::chan_utils::{make_funding_redeemscript, ChannelPublicKeys, ChannelTransactionParameters, CounterpartyChannelTransactionParameters};
+	use crate::ln::channel_keys::{DelayedPaymentBasepoint, HtlcBasepoint, RevocationBasepoint};
+	use crate::ln::channel::{calculate_our_funding_satoshis, OutboundV2Channel, MIN_CHAN_DUST_LIMIT_SATOSHIS};
 	use crate::ln::channelmanager::{create_recv_pending_htlc_info, HTLCForwardInfo, inbound_payment, PaymentId, PaymentSendFailure, RecipientOnionFields, InterceptId};
 	use crate::ln::functional_test_utils::*;
-	use crate::ln::msgs::{self, ErrorAction};
+	use crate::ln::msgs::{self, CommitmentSigned, ErrorAction, TxAddInput, TxAddOutput, TxComplete};
 	use crate::ln::msgs::ChannelMessageHandler;
 	use crate::prelude::*;
 	use crate::routing::router::{PaymentParameters, RouteParameters, find_route};
 	use crate::util::errors::APIError;
-	use crate::util::ser::Writeable;
+	use crate::util::ser::{TransactionU16LenLimited, Writeable};
 	use crate::util::test_utils;
 	use crate::util::config::{ChannelConfig, ChannelConfigUpdate};
-	use crate::sign::EntropySource;
+	use crate::sign::{EntropySource, ChannelSigner as _};
 
 	#[test]
 	fn test_notify_limits() {
@@ -14918,7 +14922,153 @@ mod tests {
 	}
 
 	// Dual-funding: V2 Channel Establishment Tests
-	// TODO(dual_funding): Complete these.
+	struct V2ChannelEstablishmentTestSession {
+		initiator_input_value_satoshis: u64,
+	}
+
+	// TODO(dual_funding): Use real node and API for creating V2 channels as initiator when available,
+	// instead of manually constructing messages.
+	fn do_test_v2_channel_establishment(session: V2ChannelEstablishmentTestSession) {
+		let chanmon_cfgs = create_chanmon_cfgs(2);
+		let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
+		let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
+		let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
+		let logger_a = test_utils::TestLogger::with_id("node a".to_owned());
+
+		// Create a funding input for the new channel along with its previous transaction.
+		let initiator_funding_inputs: Vec<_> = create_dual_funding_utxos_with_prev_txs(
+			&nodes[0], &[session.initiator_input_value_satoshis]
+		).into_iter().map(|(txin, tx)| (txin, TransactionU16LenLimited::new(tx).unwrap())).collect();
+
+		// Alice creates a dual-funded channel as initiator.
+		let funding_feerate = node_cfgs[0].fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::NonAnchorChannelFee);
+		let funding_satoshis = calculate_our_funding_satoshis(
+			true, &initiator_funding_inputs[..], funding_feerate, MIN_CHAN_DUST_LIMIT_SATOSHIS
+		).unwrap();
+		let mut  channel = OutboundV2Channel::new(
+			&LowerBoundedFeeEstimator(node_cfgs[0].fee_estimator), &nodes[0].node.entropy_source, &nodes[0].node.signer_provider,
+			nodes[1].node.get_our_node_id(), &nodes[1].node.init_features(), funding_satoshis,
+			initiator_funding_inputs.clone(), 42 /* user_channel_id */, &nodes[0].node.default_configuration, nodes[0].best_block_info().1,
+			nodes[0].node.create_and_insert_outbound_scid_alias(), ConfirmationTarget::NonAnchorChannelFee, &logger_a).unwrap();
+		let open_channel_v2_msg = channel.get_open_channel_v2(nodes[0].chain_source.chain_hash);
+
+		nodes[1].node.handle_open_channel_v2(nodes[0].node.get_our_node_id(), &open_channel_v2_msg);
+
+		let accept_channel_v2_msg = get_event_msg!(nodes[1], MessageSendEvent::SendAcceptChannelV2, nodes[0].node.get_our_node_id());
+		let channel_id = ChannelId::v2_from_revocation_basepoints(
+			&RevocationBasepoint::from(accept_channel_v2_msg.common_fields.revocation_basepoint),
+			&RevocationBasepoint::from(open_channel_v2_msg.common_fields.revocation_basepoint),
+		);
+
+		let tx_add_input_msg = TxAddInput {
+			channel_id,
+			serial_id: 2, // Even serial_id from initiator.
+			prevtx: initiator_funding_inputs[0].1.clone(),
+			prevtx_out: 0,
+			sequence: initiator_funding_inputs[0].0.sequence.0,
+			shared_input_txid: None,
+		};
+		let input_value = tx_add_input_msg.prevtx.as_transaction().output[tx_add_input_msg.prevtx_out as usize].value;
+		assert_eq!(input_value.to_sat(), session.initiator_input_value_satoshis);
+
+		nodes[1].node.handle_tx_add_input(nodes[0].node.get_our_node_id(), &tx_add_input_msg);
+
+		let _tx_complete_msg = get_event_msg!(nodes[1], MessageSendEvent::SendTxComplete, nodes[0].node.get_our_node_id());
+
+		let tx_add_output_msg = TxAddOutput {
+			channel_id,
+			serial_id: 4,
+			sats: funding_satoshis,
+			script: make_funding_redeemscript(
+				&open_channel_v2_msg.common_fields.funding_pubkey,
+				&accept_channel_v2_msg.common_fields.funding_pubkey,
+			).to_p2wsh(),
+		};
+		nodes[1].node.handle_tx_add_output(nodes[0].node.get_our_node_id(), &tx_add_output_msg);
+
+		let _tx_complete_msg = get_event_msg!(nodes[1], MessageSendEvent::SendTxComplete, nodes[0].node.get_our_node_id());
+
+		let tx_complete_msg = TxComplete {
+			channel_id,
+		};
+
+		nodes[1].node.handle_tx_complete(nodes[0].node.get_our_node_id(), &tx_complete_msg);
+		let msg_events = nodes[1].node.get_and_clear_pending_msg_events();
+		assert_eq!(msg_events.len(), 1);
+		let _msg_commitment_signed_from_1 = match msg_events[0] {
+			MessageSendEvent::UpdateHTLCs { ref node_id, ref updates } => {
+				assert_eq!(*node_id, nodes[0].node.get_our_node_id());
+				updates.commitment_signed.clone()
+			},
+			_ => panic!("Unexpected event"),
+		};
+
+		let (funding_outpoint, channel_type_features) = {
+			let per_peer_state = nodes[1].node.per_peer_state.read().unwrap();
+			let peer_state = per_peer_state.get(&nodes[0].node.get_our_node_id()).unwrap().lock().unwrap();
+			let channel_context = peer_state
+				.channel_by_id.get(&tx_complete_msg.channel_id).unwrap().context();
+			(channel_context.get_funding_txo(), channel_context.get_channel_type().clone())
+		};
+
+		let channel_transaction_parameters = ChannelTransactionParameters {
+			counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
+				pubkeys: ChannelPublicKeys {
+					funding_pubkey: accept_channel_v2_msg.common_fields.funding_pubkey,
+					revocation_basepoint: RevocationBasepoint(accept_channel_v2_msg.common_fields.revocation_basepoint),
+					payment_point: accept_channel_v2_msg.common_fields.payment_basepoint,
+					delayed_payment_basepoint: DelayedPaymentBasepoint(accept_channel_v2_msg.common_fields.delayed_payment_basepoint),
+					htlc_basepoint: HtlcBasepoint(accept_channel_v2_msg.common_fields.htlc_basepoint),
+				},
+				selected_contest_delay: accept_channel_v2_msg.common_fields.to_self_delay,
+			}),
+			holder_pubkeys: ChannelPublicKeys {
+				funding_pubkey: open_channel_v2_msg.common_fields.funding_pubkey,
+				revocation_basepoint: RevocationBasepoint(open_channel_v2_msg.common_fields.revocation_basepoint),
+				payment_point: open_channel_v2_msg.common_fields.payment_basepoint,
+				delayed_payment_basepoint: DelayedPaymentBasepoint(open_channel_v2_msg.common_fields.delayed_payment_basepoint),
+				htlc_basepoint: HtlcBasepoint(open_channel_v2_msg.common_fields.htlc_basepoint),
+			},
+			holder_selected_contest_delay: open_channel_v2_msg.common_fields.to_self_delay,
+			is_outbound_from_holder: true,
+			funding_outpoint,
+			channel_type_features,
+		};
+
+		channel.context.get_mut_signer().as_mut_ecdsa().unwrap().provide_channel_parameters(&channel_transaction_parameters);
+
+		let msg_commitment_signed_from_0 = CommitmentSigned {
+			channel_id,
+			signature: channel.context.get_initial_counterparty_commitment_signature_for_test(
+				&&logger_a,
+				channel_transaction_parameters,
+				accept_channel_v2_msg.common_fields.first_per_commitment_point,
+			).unwrap(),
+			htlc_signatures: vec![],
+			batch: None,
+			#[cfg(taproot)]
+			partial_signature_with_nonce: None,
+		};
+
+		// Handle the initial commitment_signed exchange. Order is not important here.
+		nodes[1].node.handle_commitment_signed(nodes[0].node.get_our_node_id(), &msg_commitment_signed_from_0);
+		check_added_monitors(&nodes[1], 1);
+
+		let events = nodes[1].node.get_and_clear_pending_events();
+		assert_eq!(events.len(), 1);
+		match events[0] {
+			Event::ChannelPending { channel_id, .. } => channel_id == channel.context.channel_id(),
+			_ => panic!("Unexpected event"),
+		};
+	}
+
+	#[test]
+	fn test_v2_channel_establishment() {
+		// Only initiator contributes
+		do_test_v2_channel_establishment(V2ChannelEstablishmentTestSession {
+			initiator_input_value_satoshis: 100_000,
+		});
+	}
 }
 
 #[cfg(ldk_bench)]
diff --git a/lightning/src/ln/functional_test_utils.rs b/lightning/src/ln/functional_test_utils.rs
@@ -38,17 +38,20 @@ use crate::util::test_utils;
 use crate::util::test_utils::{TestChainMonitor, TestScorer, TestKeysInterface};
 use crate::util::ser::{ReadableArgs, Writeable};
 
+use bitcoin::WPubkeyHash;
 use bitcoin::amount::Amount;
-use bitcoin::block::{Block, Header, Version};
-use bitcoin::locktime::absolute::LockTime;
-use bitcoin::transaction::{Transaction, TxIn, TxOut};
+use bitcoin::block::{Block, Header, Version as BlockVersion};
+use bitcoin::locktime::absolute::{LockTime, LOCK_TIME_THRESHOLD};
+use bitcoin::transaction::{Sequence, Transaction, TxIn, TxOut};
 use bitcoin::hash_types::{BlockHash, TxMerkleNode};
 use bitcoin::hashes::sha256::Hash as Sha256;
 use bitcoin::hashes::Hash as _;
 use bitcoin::network::Network;
 use bitcoin::pow::CompactTarget;
+use bitcoin::script::ScriptBuf;
 use bitcoin::secp256k1::{PublicKey, SecretKey};
-use bitcoin::transaction;
+use bitcoin::transaction::{self, Version as TxVersion};
+use bitcoin::witness::Witness;
 
 use alloc::rc::Rc;
 use core::cell::RefCell;
@@ -90,7 +93,7 @@ pub fn mine_transaction_without_consistency_checks<'a, 'b, 'c, 'd>(node: &'a Nod
 	let height = node.best_block_info().1 + 1;
 	let mut block = Block {
 		header: Header {
-			version: Version::NO_SOFT_FORK_SIGNALLING,
+			version: BlockVersion::NO_SOFT_FORK_SIGNALLING,
 			prev_blockhash: node.best_block_hash(),
 			merkle_root: TxMerkleNode::all_zeros(),
 			time: height,
@@ -217,7 +220,7 @@ impl ConnectStyle {
 
 pub fn create_dummy_header(prev_blockhash: BlockHash, time: u32) -> Header {
 	Header {
-		version: Version::NO_SOFT_FORK_SIGNALLING,
+		version: BlockVersion::NO_SOFT_FORK_SIGNALLING,
 		prev_blockhash,
 		merkle_root: TxMerkleNode::all_zeros(),
 		time,
@@ -1221,6 +1224,37 @@ fn internal_create_funding_transaction<'a, 'b, 'c>(node: &Node<'a, 'b, 'c>,
 	}
 }
 
+pub fn create_dual_funding_utxos_with_prev_txs(
+	node: &Node<'_, '_, '_>, utxo_values_in_satoshis: &[u64],
+) -> Vec<(TxIn, Transaction)> {
+	// Ensure we have unique transactions per node by using the locktime.
+	let tx = Transaction {
+		version: TxVersion::TWO,
+		lock_time: LockTime::from_height(
+			u32::from_be_bytes(node.keys_manager.get_secure_random_bytes()[0..4].try_into().unwrap()) % LOCK_TIME_THRESHOLD
+		).unwrap(),
+		input: vec![],
+		output: utxo_values_in_satoshis.iter().map(|value_satoshis| TxOut {
+			value: Amount::from_sat(*value_satoshis), script_pubkey: ScriptBuf::new_p2wpkh(&WPubkeyHash::all_zeros()),
+		}).collect()
+	};
+
+	let mut result = vec![];
+	for i in 0..utxo_values_in_satoshis.len() {
+		result.push(
+			(TxIn {
+				previous_output: OutPoint {
+					txid: tx.compute_txid(),
+					index: i as u16,
+				}.into_bitcoin_outpoint(),
+				script_sig: ScriptBuf::new(),
+				sequence: Sequence::ZERO,
+				witness: Witness::new(),
+			}, tx.clone()));
+	}
+	result
+}
+
 pub fn sign_funding_transaction<'a, 'b, 'c>(node_a: &Node<'a, 'b, 'c>, node_b: &Node<'a, 'b, 'c>, channel_value: u64, expected_temporary_channel_id: ChannelId) -> Transaction {
 	let (temporary_channel_id, tx, funding_output) = create_funding_transaction(node_a, &node_b.node.get_our_node_id(), channel_value, 42);
 	assert_eq!(temporary_channel_id, expected_temporary_channel_id);
