From: Wilmer Paulino Date: Wed, 5 Jul 2023 16:47:05 +0000 (-0700) Subject: Add transaction-related helpers to AnchorDescriptor X-Git-Tag: v0.0.116-rc1~5^2~1 X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=0dbfe245a9a561059d06e9988fe318cb08a05598;p=rust-lightning Add transaction-related helpers to AnchorDescriptor This provides a similar interface as `HTLCDescriptor` for users which choose to implement their own bump transaction event handler. --- diff --git a/lightning/src/events/bump_transaction.rs b/lightning/src/events/bump_transaction.rs index 5ea9bdb8e..9d086a26d 100644 --- a/lightning/src/events/bump_transaction.rs +++ b/lightning/src/events/bump_transaction.rs @@ -76,6 +76,30 @@ pub struct AnchorDescriptor { } impl AnchorDescriptor { + /// 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(&self, signer_provider: &SP) -> ::Signer where @@ -649,12 +673,7 @@ 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 +707,7 @@ 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(())