From fe25bbb44ea879e6b84e0cd6f62fd53058d77417 Mon Sep 17 00:00:00 2001
From: Arik Sosman <git@arik.io>
Date: Wed, 29 Mar 2023 15:21:30 -0700
Subject: [PATCH] Update the `CommitmentSigned` message for Taproot support.

---
 lightning/src/ln/channel.rs          |  2 ++
 lightning/src/ln/functional_tests.rs |  8 ++++++--
 lightning/src/ln/msgs.rs             | 15 +++++++++++++++
 3 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index 43604c191..e2b3fb066 100644
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -5923,6 +5923,8 @@ impl<Signer: WriteableEcdsaChannelSigner> Channel<Signer> {
 			channel_id: self.channel_id,
 			signature,
 			htlc_signatures,
+			#[cfg(taproot)]
+			partial_signature_with_nonce: None,
 		}, (counterparty_commitment_txid, commitment_stats.htlcs_included)))
 	}
 
diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs
index 56586b0a2..af547b3af 100644
--- a/lightning/src/ln/functional_tests.rs
+++ b/lightning/src/ln/functional_tests.rs
@@ -735,7 +735,9 @@ fn test_update_fee_that_funder_cannot_afford() {
 	let commit_signed_msg = msgs::CommitmentSigned {
 		channel_id: chan.2,
 		signature: res.0,
-		htlc_signatures: res.1
+		htlc_signatures: res.1,
+		#[cfg(taproot)]
+		partial_signature_with_nonce: None,
 	};
 
 	let update_fee = msgs::UpdateFee {
@@ -1455,7 +1457,9 @@ fn test_fee_spike_violation_fails_htlc() {
 	let commit_signed_msg = msgs::CommitmentSigned {
 		channel_id: chan.2,
 		signature: res.0,
-		htlc_signatures: res.1
+		htlc_signatures: res.1,
+		#[cfg(taproot)]
+		partial_signature_with_nonce: None,
 	};
 
 	// Send the commitment_signed message to the nodes[1].
diff --git a/lightning/src/ln/msgs.rs b/lightning/src/ln/msgs.rs
index 5e51fc0a9..61e18648a 100644
--- a/lightning/src/ln/msgs.rs
+++ b/lightning/src/ln/msgs.rs
@@ -426,6 +426,9 @@ pub struct CommitmentSigned {
 	pub signature: Signature,
 	/// Signatures on the HTLC transactions
 	pub htlc_signatures: Vec<Signature>,
+	#[cfg(taproot)]
+	/// The partial Taproot signature on the commitment transaction
+	pub partial_signature_with_nonce: Option<PartialSignatureWithNonce>,
 }
 
 /// A [`revoke_and_ack`] message to be sent to or received from a peer.
@@ -1402,12 +1405,22 @@ impl_writeable!(ClosingSignedFeeRange, {
 	max_fee_satoshis
 });
 
+#[cfg(not(taproot))]
 impl_writeable_msg!(CommitmentSigned, {
 	channel_id,
 	signature,
 	htlc_signatures
 }, {});
 
+#[cfg(taproot)]
+impl_writeable_msg!(CommitmentSigned, {
+	channel_id,
+	signature,
+	htlc_signatures
+}, {
+	(2, partial_signature_with_nonce, option)
+});
+
 impl_writeable!(DecodedOnionErrorPacket, {
 	hmac,
 	failuremsg,
@@ -2713,6 +2726,8 @@ mod tests {
 			channel_id: [2; 32],
 			signature: sig_1,
 			htlc_signatures: if htlcs { vec![sig_2, sig_3, sig_4] } else { Vec::new() },
+			#[cfg(taproot)]
+			partial_signature_with_nonce: None,
 		};
 		let encoded_value = commitment_signed.encode();
 		let mut target_value = hex::decode("0202020202020202020202020202020202020202020202020202020202020202d977cb9b53d93a6ff64bb5f1e158b4094b66e798fb12911168a3ccdf80a83096340a6a95da0ae8d9f776528eecdbb747eb6b545495a4319ed5378e35b21e073a").unwrap();
-- 
2.39.5