Rename KeysInterface ready_channel to provide_channel_parameters
authorWilmer Paulino <wilmer.paulino@gmail.com>
Tue, 29 Nov 2022 17:05:47 +0000 (09:05 -0800)
committerWilmer Paulino <wilmer.paulino@gmail.com>
Mon, 5 Dec 2022 20:11:26 +0000 (12:11 -0800)
Now that ready_channel is also called on startup upon deserializing
channels, we opt to rename it to a more indicative name.

We also derive `PartialEq` on ChannelTransactionParameters to allow
implementations to determine whether `provide_channel_parameters` calls
are idempotent after the channel parameters have already been provided.

lightning/src/chain/keysinterface.rs
lightning/src/ln/chan_utils.rs
lightning/src/ln/channel.rs
lightning/src/util/enforcing_trait_impls.rs

index 9f3cfc531e2684d7491fed931fbe6fcd7e03b4c3..ec45d1df6e8d7f68fe427bb93b6c6f0b84afc90c 100644 (file)
@@ -161,7 +161,7 @@ pub enum SpendableOutputDescriptor {
        ///
        /// To derive the revocation_pubkey provided here (which is used in the witness
        /// script generation), you must pass the counterparty revocation_basepoint (which appears in the
-       /// call to Sign::ready_channel) and the provided per_commitment point
+       /// call to Sign::provide_channel_parameters) and the provided per_commitment point
        /// to chan_utils::derive_public_revocation_key.
        ///
        /// The witness script which is hashed and included in the output script_pubkey may be
@@ -368,16 +368,12 @@ pub trait BaseSign {
                -> Result<(Signature, Signature), ()>;
 
        /// Set the counterparty static channel data, including basepoints,
-       /// counterparty_selected/holder_selected_contest_delay and funding outpoint.
-       /// This is done as soon as the funding outpoint is known.  Since these are static channel data,
-       /// they MUST NOT be allowed to change to different values once set.
+       /// counterparty_selected/holder_selected_contest_delay and funding outpoint. Since these are
+       /// static channel data, they MUST NOT be allowed to change to different values once set, as LDK
+       /// may call this method more than once.
        ///
        /// channel_parameters.is_populated() MUST be true.
-       ///
-       /// We bind holder_selected_contest_delay late here for API convenience.
-       ///
-       /// Will be called before any signatures are applied.
-       fn ready_channel(&mut self, channel_parameters: &ChannelTransactionParameters);
+       fn provide_channel_parameters(&mut self, channel_parameters: &ChannelTransactionParameters);
 }
 
 /// A cloneable signer.
@@ -583,39 +579,39 @@ impl InMemorySigner {
        }
 
        /// Counterparty pubkeys.
-       /// Will panic if ready_channel wasn't called.
+       /// Will panic if provide_channel_parameters wasn't called.
        pub fn counterparty_pubkeys(&self) -> &ChannelPublicKeys { &self.get_channel_parameters().counterparty_parameters.as_ref().unwrap().pubkeys }
 
        /// The contest_delay value specified by our counterparty and applied on holder-broadcastable
        /// transactions, ie the amount of time that we have to wait to recover our funds if we
        /// broadcast a transaction.
-       /// Will panic if ready_channel wasn't called.
+       /// Will panic if provide_channel_parameters wasn't called.
        pub fn counterparty_selected_contest_delay(&self) -> u16 { self.get_channel_parameters().counterparty_parameters.as_ref().unwrap().selected_contest_delay }
 
        /// The contest_delay value specified by us and applied on transactions broadcastable
        /// by our counterparty, ie the amount of time that they have to wait to recover their funds
        /// if they broadcast a transaction.
-       /// Will panic if ready_channel wasn't called.
+       /// Will panic if provide_channel_parameters wasn't called.
        pub fn holder_selected_contest_delay(&self) -> u16 { self.get_channel_parameters().holder_selected_contest_delay }
 
        /// Whether the holder is the initiator
-       /// Will panic if ready_channel wasn't called.
+       /// Will panic if provide_channel_parameters wasn't called.
        pub fn is_outbound(&self) -> bool { self.get_channel_parameters().is_outbound_from_holder }
 
        /// Funding outpoint
-       /// Will panic if ready_channel wasn't called.
+       /// Will panic if provide_channel_parameters wasn't called.
        pub fn funding_outpoint(&self) -> &OutPoint { self.get_channel_parameters().funding_outpoint.as_ref().unwrap() }
 
        /// Obtain a ChannelTransactionParameters for this channel, to be used when verifying or
        /// building transactions.
        ///
-       /// Will panic if ready_channel wasn't called.
+       /// Will panic if provide_channel_parameters wasn't called.
        pub fn get_channel_parameters(&self) -> &ChannelTransactionParameters {
                self.channel_parameters.as_ref().unwrap()
        }
 
        /// Whether anchors should be used.
-       /// Will panic if ready_channel wasn't called.
+       /// Will panic if provide_channel_parameters wasn't called.
        pub fn opt_anchors(&self) -> bool {
                self.get_channel_parameters().opt_anchors.is_some()
        }
@@ -819,8 +815,12 @@ impl BaseSign for InMemorySigner {
                Ok((sign(secp_ctx, &msghash, &self.node_secret), sign(secp_ctx, &msghash, &self.funding_key)))
        }
 
-       fn ready_channel(&mut self, channel_parameters: &ChannelTransactionParameters) {
-               assert!(self.channel_parameters.is_none(), "Acceptance already noted");
+       fn provide_channel_parameters(&mut self, channel_parameters: &ChannelTransactionParameters) {
+               assert!(self.channel_parameters.is_none() || self.channel_parameters.as_ref().unwrap() == channel_parameters);
+               if self.channel_parameters.is_some() {
+                       // The channel parameters were already set and they match, return early.
+                       return;
+               }
                assert!(channel_parameters.is_populated(), "Channel parameters must be fully populated");
                self.channel_parameters = Some(channel_parameters.clone());
        }
index e03989513a4e1e52e20a4f0014217c1268179a80..4a66f85e2c98e63281fd82e5e2cfd42f761e416a 100644 (file)
@@ -763,7 +763,7 @@ pub fn build_anchor_input_witness(funding_key: &PublicKey, funding_sig: &Signatu
 ///
 /// Normally, this is converted to the broadcaster/countersignatory-organized DirectedChannelTransactionParameters
 /// before use, via the as_holder_broadcastable and as_counterparty_broadcastable functions.
-#[derive(Clone)]
+#[derive(Clone, PartialEq)]
 pub struct ChannelTransactionParameters {
        /// Holder public keys
        pub holder_pubkeys: ChannelPublicKeys,
@@ -787,7 +787,7 @@ pub struct ChannelTransactionParameters {
 }
 
 /// Late-bound per-channel counterparty data used to build transactions.
-#[derive(Clone)]
+#[derive(Clone, PartialEq)]
 pub struct CounterpartyChannelTransactionParameters {
        /// Counter-party public keys
        pub pubkeys: ChannelPublicKeys,
index cd6448d088cdec223c3927dafbfcde2eff270e06..debd4dfcf15297023e0fe88b9b04637cc6d43bcb 100644 (file)
@@ -2215,7 +2215,7 @@ impl<Signer: Sign> Channel<Signer> {
                self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
                // This is an externally observable change before we finish all our checks.  In particular
                // funding_created_signature may fail.
-               self.holder_signer.ready_channel(&self.channel_transaction_parameters);
+               self.holder_signer.provide_channel_parameters(&self.channel_transaction_parameters);
 
                let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
                        Ok(res) => res,
@@ -5250,7 +5250,7 @@ impl<Signer: Sign> Channel<Signer> {
                }
 
                self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
-               self.holder_signer.ready_channel(&self.channel_transaction_parameters);
+               self.holder_signer.provide_channel_parameters(&self.channel_transaction_parameters);
 
                let signature = match self.get_outbound_funding_created_signature(logger) {
                        Ok(res) => res,
@@ -7296,7 +7296,7 @@ mod tests {
                                selected_contest_delay: 144
                        });
                chan.channel_transaction_parameters.funding_outpoint = Some(funding_info);
-               signer.ready_channel(&chan.channel_transaction_parameters);
+               signer.provide_channel_parameters(&chan.channel_transaction_parameters);
 
                assert_eq!(counterparty_pubkeys.payment_point.serialize()[..],
                           hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
index 55bad7f63f24502bf84b774329fbc1487a5166a9..21ef5d4b17887361d4faed1b885ecb765c6a2339 100644 (file)
@@ -215,8 +215,8 @@ impl BaseSign for EnforcingSigner {
                self.inner.sign_channel_announcement(msg, secp_ctx)
        }
 
-       fn ready_channel(&mut self, channel_parameters: &ChannelTransactionParameters) {
-               self.inner.ready_channel(channel_parameters)
+       fn provide_channel_parameters(&mut self, channel_parameters: &ChannelTransactionParameters) {
+               self.inner.provide_channel_parameters(channel_parameters)
        }
 }