Drop requirement that all ChannelKeys expose revocaion_basepoint

Author: TheBlueMatt

lightning/src/chain/keysinterface.rs

@@ -195,8 +195,6 @@ impl Readable for SpendableOutputDescriptor {
 // TODO: We should remove Clone by instead requesting a new ChannelKeys copy when we create
 // ChannelMonitors instead of expecting to clone the one out of the Channel into the monitors.
 pub trait ChannelKeys : Send+Clone {
-	/// Gets the local secret key for blinded revocation pubkey
-	fn revocation_base_key<'a>(&'a self) -> &'a SecretKey;
 	/// Gets the local secret key used in HTLC-Success/HTLC-Timeout txn and to_local output
 	fn delayed_payment_base_key<'a>(&'a self) -> &'a SecretKey;
 	/// Gets the local htlc secret key used in commitment tx htlc outputs
@@ -410,7 +408,6 @@ impl InMemoryChannelKeys {
 }
 
 impl ChannelKeys for InMemoryChannelKeys {
-	fn revocation_base_key(&self) -> &SecretKey { &self.revocation_base_key }
 	fn delayed_payment_base_key(&self) -> &SecretKey { &self.delayed_payment_base_key }
 	fn htlc_base_key(&self) -> &SecretKey { &self.htlc_base_key }
 	fn commitment_seed(&self) -> &[u8; 32] { &self.commitment_seed }

lightning/src/ln/channel.rs

@@ -1108,11 +1108,11 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	fn build_remote_transaction_keys(&self) -> Result<TxCreationKeys, ChannelError> {
 		//TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
 		//may see payments to it!
-		let revocation_basepoint = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.revocation_base_key());
+		let revocation_basepoint = &self.local_keys.pubkeys().revocation_basepoint;
 		let htlc_basepoint = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.htlc_base_key());
 		let their_pubkeys = self.their_pubkeys.as_ref().unwrap();
 
-		Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &self.their_cur_commitment_point.unwrap(), &their_pubkeys.delayed_payment_basepoint, &their_pubkeys.htlc_basepoint, &revocation_basepoint, &htlc_basepoint), "Remote tx keys generation got bogus keys"))
+		Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &self.their_cur_commitment_point.unwrap(), &their_pubkeys.delayed_payment_basepoint, &their_pubkeys.htlc_basepoint, revocation_basepoint, &htlc_basepoint), "Remote tx keys generation got bogus keys"))
 	}
 
 	/// Gets the redeemscript for the funding transaction output (ie the funding transaction output
@@ -3315,7 +3315,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			to_self_delay: self.our_to_self_delay,
 			max_accepted_htlcs: OUR_MAX_HTLCS,
 			funding_pubkey: local_keys.funding_pubkey,
-			revocation_basepoint: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.revocation_base_key()),
+			revocation_basepoint: local_keys.revocation_basepoint,
 			payment_point: local_keys.payment_point,
 			delayed_payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.delayed_payment_base_key()),
 			htlc_basepoint: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.htlc_base_key()),
@@ -3349,7 +3349,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			to_self_delay: self.our_to_self_delay,
 			max_accepted_htlcs: OUR_MAX_HTLCS,
 			funding_pubkey: local_keys.funding_pubkey,
-			revocation_basepoint: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.revocation_base_key()),
+			revocation_basepoint: local_keys.revocation_basepoint,
 			payment_point: local_keys.payment_point,
 			delayed_payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.delayed_payment_base_key()),
 			htlc_basepoint: PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.htlc_base_key()),

lightning/src/util/enforcing_trait_impls.rs

@@ -35,7 +35,6 @@ impl EnforcingChannelKeys {
 impl EnforcingChannelKeys {
 	fn check_keys<T: secp256k1::Signing + secp256k1::Verification>(&self, secp_ctx: &Secp256k1<T>,
 	                                                               keys: &TxCreationKeys) {
-		let revocation_base = PublicKey::from_secret_key(secp_ctx, &self.inner.revocation_base_key());
 		let htlc_base = PublicKey::from_secret_key(secp_ctx, &self.inner.htlc_base_key());
 
 		let remote_points = self.inner.remote_channel_pubkeys.as_ref().unwrap();
@@ -44,14 +43,13 @@ impl EnforcingChannelKeys {
 		                                        &keys.per_commitment_point,
 		                                        &remote_points.delayed_payment_basepoint,
 		                                        &remote_points.htlc_basepoint,
-		                                        &revocation_base,
+		                                        &self.inner.pubkeys().revocation_basepoint,
 		                                        &htlc_base).unwrap();
 		if keys != &keys_expected { panic!("derived different per-tx keys") }
 	}
 }
 
 impl ChannelKeys for EnforcingChannelKeys {
-	fn revocation_base_key(&self) -> &SecretKey { self.inner.revocation_base_key() }
 	fn delayed_payment_base_key(&self) -> &SecretKey { self.inner.delayed_payment_base_key() }
 	fn htlc_base_key(&self) -> &SecretKey { self.inner.htlc_base_key() }
 	fn commitment_seed(&self) -> &[u8; 32] { self.inner.commitment_seed() }