X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fevents%2Fbump_transaction.rs;h=dbe539505d6ca733f53a44e4ae0f515523373395;hb=19de4353d52bca8021ba3e1b8f4b036d5f5a8648;hp=5ea9bdb8e292fa4e4a6d1756a5d6c1a4df782e03;hpb=690ad18b22fbc1917b77ae5ef820a9a7fd967020;p=rust-lightning

diff --git a/lightning/src/events/bump_transaction.rs b/lightning/src/events/bump_transaction.rs
index 5ea9bdb8..dbe53950 100644
--- a/lightning/src/events/bump_transaction.rs
+++ b/lightning/src/events/bump_transaction.rs
@@ -12,12 +12,12 @@
 //! [`Event`]: crate::events::Event
 
 use alloc::collections::BTreeMap;
-use core::convert::TryInto;
 use core::ops::Deref;
 
-use crate::chain::chaininterface::BroadcasterInterface;
+use crate::chain::chaininterface::{BroadcasterInterface, compute_feerate_sat_per_1000_weight, fee_for_weight};
 use crate::chain::ClaimId;
 use crate::io_extras::sink;
+use crate::ln::channel::ANCHOR_OUTPUT_VALUE_SATOSHI;
 use crate::ln::chan_utils;
 use crate::ln::chan_utils::{
 	ANCHOR_INPUT_WITNESS_WEIGHT, HTLC_SUCCESS_INPUT_ANCHOR_WITNESS_WEIGHT,
@@ -43,14 +43,6 @@ const BASE_INPUT_SIZE: u64 = 32 /* txid */ + 4 /* vout */ + 4 /* sequence */;
 
 const BASE_INPUT_WEIGHT: u64 = BASE_INPUT_SIZE * WITNESS_SCALE_FACTOR as u64;
 
-// TODO: Define typed abstraction over feerates to handle their conversions.
-fn compute_feerate_sat_per_1000_weight(fee_sat: u64, weight: u64) -> u32 {
-	(fee_sat * 1000 / weight).try_into().unwrap_or(u32::max_value())
-}
-const fn fee_for_weight(feerate_sat_per_1000_weight: u32, weight: u64) -> u64 {
-	((feerate_sat_per_1000_weight as u64 * weight) + 1000 - 1) / 1000
-}
-
 /// The parameters required to derive a channel signer via [`SignerProvider`].
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub struct ChannelDerivationParameters {
@@ -76,6 +68,39 @@ pub struct AnchorDescriptor {
 }
 
 impl AnchorDescriptor {
+	/// Returns the UTXO to be spent by the anchor input, which can be obtained via
+	/// [`Self::unsigned_tx_input`].
+	pub fn previous_utxo(&self) -> TxOut {
+		TxOut {
+			script_pubkey: self.witness_script().to_v0_p2wsh(),
+			value: ANCHOR_OUTPUT_VALUE_SATOSHI,
+		}
+	}
+
+	/// Returns the unsigned transaction input spending the anchor output in the commitment
+	/// transaction.
+	pub fn unsigned_tx_input(&self) -> TxIn {
+		TxIn {
+			previous_output: self.outpoint.clone(),
+			script_sig: Script::new(),
+			sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
+			witness: Witness::new(),
+		}
+	}
+
+	/// Returns the witness script of the anchor output in the commitment transaction.
+	pub fn witness_script(&self) -> Script {
+		let channel_params = self.channel_derivation_parameters.transaction_parameters.as_holder_broadcastable();
+		chan_utils::get_anchor_redeemscript(&channel_params.broadcaster_pubkeys().funding_pubkey)
+	}
+
+	/// Returns the fully signed witness required to spend the anchor output in the commitment
+	/// transaction.
+	pub fn tx_input_witness(&self, signature: &Signature) -> Witness {
+		let channel_params = self.channel_derivation_parameters.transaction_parameters.as_holder_broadcastable();
+		chan_utils::build_anchor_input_witness(&channel_params.broadcaster_pubkeys().funding_pubkey, signature)
+	}
+
 	/// Derives the channel signer required to sign the anchor input.
 	pub fn derive_channel_signer<SP: Deref>(&self, signer_provider: &SP) -> <SP::Target as SignerProvider>::Signer
 	where
@@ -115,6 +140,15 @@ pub struct HTLCDescriptor {
 }
 
 impl HTLCDescriptor {
+	/// Returns the UTXO to be spent by the HTLC input, which can be obtained via
+	/// [`Self::unsigned_tx_input`].
+	pub fn previous_utxo<C: secp256k1::Signing + secp256k1::Verification>(&self, secp: &Secp256k1<C>) -> TxOut {
+		TxOut {
+			script_pubkey: self.witness_script(secp).to_v0_p2wsh(),
+			value: self.htlc.amount_msat / 1000,
+		}
+	}
+
 	/// Returns the unsigned transaction input spending the HTLC output in the commitment
 	/// transaction.
 	pub fn unsigned_tx_input(&self) -> TxIn {
@@ -301,6 +335,8 @@ pub enum BumpTransactionEvent {
 pub struct Input {
 	/// The unique identifier of the input.
 	pub outpoint: OutPoint,
+	/// The UTXO being spent by the input.
+	pub previous_utxo: TxOut,
 	/// The upper-bound weight consumed by the input's full [`TxIn::script_sig`] and
 	/// [`TxIn::witness`], each with their lengths included, required to satisfy the output's
 	/// script.
@@ -640,6 +676,7 @@ where
 	) -> Result<Transaction, ()> {
 		let must_spend = vec![Input {
 			outpoint: anchor_descriptor.outpoint,
+			previous_utxo: anchor_descriptor.previous_utxo(),
 			satisfaction_weight: commitment_tx.weight() as u64 + ANCHOR_INPUT_WITNESS_WEIGHT + EMPTY_SCRIPT_SIG_WEIGHT,
 		}];
 		let coin_selection = self.utxo_source.select_confirmed_utxos(
@@ -649,12 +686,7 @@ where
 		let mut tx = Transaction {
 			version: 2,
 			lock_time: PackedLockTime::ZERO, // TODO: Use next best height.
-			input: vec![TxIn {
-				previous_output: anchor_descriptor.outpoint,
-				script_sig: Script::new(),
-				sequence: Sequence::ZERO,
-				witness: Witness::new(),
-			}],
+			input: vec![anchor_descriptor.unsigned_tx_input()],
 			output: vec![],
 		};
 		self.process_coin_selection(&mut tx, coin_selection);
@@ -688,8 +720,7 @@ where
 		self.utxo_source.sign_tx(&mut anchor_tx)?;
 		let signer = anchor_descriptor.derive_channel_signer(&self.signer_provider);
 		let anchor_sig = signer.sign_holder_anchor_input(&anchor_tx, 0, &self.secp)?;
-		anchor_tx.input[0].witness =
-			chan_utils::build_anchor_input_witness(&signer.pubkeys().funding_pubkey, &anchor_sig);
+		anchor_tx.input[0].witness = anchor_descriptor.tx_input_witness(&anchor_sig);
 
 		self.broadcaster.broadcast_transactions(&[&commitment_tx, &anchor_tx]);
 		Ok(())
@@ -712,6 +743,7 @@ where
 			let htlc_input = htlc_descriptor.unsigned_tx_input();
 			must_spend.push(Input {
 				outpoint: htlc_input.previous_output.clone(),
+				previous_utxo: htlc_descriptor.previous_utxo(&self.secp),
 				satisfaction_weight: EMPTY_SCRIPT_SIG_WEIGHT + if htlc_descriptor.preimage.is_some() {
 					HTLC_SUCCESS_INPUT_ANCHOR_WITNESS_WEIGHT
 				} else {