Add cltv_expiry_delta to ChannelHandshakeConfig

Author: matchacactus

lightning/src/ln/channel.rs

@@ -775,7 +775,7 @@ impl<Signer: Sign> Channel<Signer> {
 
 			forwarding_fee_base_msat: handshake_config.forwarding_fee_base_msat,
 			forwarding_fee_proportional_millionths: handshake_config.forwarding_fee_proportional_millionths,
-			cltv_expiry_delta: config.channel_options.clone().cltv_expiry_delta,
+			cltv_expiry_delta: handshake_config.cltv_expiry_delta,
 
 			channel_id: keys_provider.get_secure_random_bytes(),
 			channel_state: ChannelState::OurInitSent as u32,
@@ -1078,7 +1078,7 @@ impl<Signer: Sign> Channel<Signer> {
 
 			forwarding_fee_base_msat: handshake_config.forwarding_fee_base_msat,
 			forwarding_fee_proportional_millionths: handshake_config.forwarding_fee_proportional_millionths,
-			cltv_expiry_delta: local_config.cltv_expiry_delta,
+			cltv_expiry_delta: handshake_config.cltv_expiry_delta,
 
 			channel_id: msg.temporary_channel_id,
 			channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
@@ -5206,7 +5206,7 @@ impl<Signer: Sign> Writeable for Channel<Signer> {
 		// Write out the old serialization for the config object. This is read by version-1
 		// deserializers, but we will read the version in the TLV at the end instead.
 		self.forwarding_fee_proportional_millionths.write(writer)?;
-		self.config.cltv_expiry_delta.write(writer)?;
+		self.cltv_expiry_delta.write(writer)?;
 		self.config.announced_channel.write(writer)?;
 		self.config.commit_upfront_shutdown_pubkey.write(writer)?;
 
@@ -5471,14 +5471,14 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<Signer>
 
 		if ver == 1 {
 			// Read the old serialization of the ChannelConfig from version 0.0.98.handshake_config.as_mut().unwrap().forwarding_fee_proportional_millionths = Readable::read(reader)?;
-			config.as_mut().unwrap().cltv_expiry_delta = Readable::read(reader)?;
 			config.as_mut().unwrap().announced_channel = Readable::read(reader)?;
 			config.as_mut().unwrap().commit_upfront_shutdown_pubkey = Readable::read(reader)?;
 		} else {
 			// Read the 8 bytes of backwards-compatibility ChannelConfig data.
 			let mut _val: u64 = Readable::read(reader)?;
 		}
-
+		
+		let cltv_expiry_delta = Readable::read(reader)?;
 		let channel_id = Readable::read(reader)?;
 		let channel_state = Readable::read(reader)?;
 		let channel_value_satoshis = Readable::read(reader)?;
@@ -5728,7 +5728,7 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<Signer>
 			config: config.unwrap(),
 			forwarding_fee_base_msat: handshake_config.unwrap().forwarding_fee_base_msat,
 			forwarding_fee_proportional_millionths: handshake_config.unwrap().forwarding_fee_proportional_millionths,
-			cltv_expiry_delta: config.unwrap().cltv_expiry_delta,
+			cltv_expiry_delta: handshake_config.unwrap().cltv_expiry_delta,
 
 			channel_id,
 			channel_state,

lightning/src/ln/functional_test_utils.rs

@@ -1731,7 +1731,7 @@ pub fn test_default_channel_config() -> UserConfig {
 	let mut default_config = UserConfig::default();
 	// Set cltv_expiry_delta slightly lower to keep the final CLTV values inside one byte in our
 	// tests so that our script-length checks don't fail (see ACCEPTED_HTLC_SCRIPT_WEIGHT).
-	default_config.channel_options.cltv_expiry_delta = 6*6;
+	default_config.own_channel_config.cltv_expiry_delta = 6*6;
 	default_config.channel_options.announced_channel = true;
 	default_config.peer_channel_config_limits.force_announced_channel_preference = false;
 	// When most of our tests were written, the default HTLC minimum was fixed at 1000.

lightning/src/util/config.rs

@@ -67,6 +67,26 @@ pub struct ChannelHandshakeConfig {
 	///
 	/// [`forwarding_fee_proportional_millionths`]: ChannelConfig::forwarding_fee_proportional_millionths
 	pub forwarding_fee_base_msat: u32,
+	/// The difference in the CLTV value between incoming HTLCs and an outbound HTLC forwarded over
+	/// the channel this config applies to.
+	///
+	/// This is analogous to [`ChannelHandshakeConfig::our_to_self_delay`] but applies to in-flight
+	/// HTLC balance when a channel appears on-chain whereas
+	/// [`ChannelHandshakeConfig::our_to_self_delay`] applies to the remaining
+	/// (non-HTLC-encumbered) balance.
+	///
+	/// Thus, for HTLC-encumbered balances to be enforced on-chain when a channel is force-closed,
+	/// we (or one of our watchtowers) MUST be online to check for broadcast of the current
+	/// commitment transaction at least once per this many blocks (minus some margin to allow us
+	/// enough time to broadcast and confirm a transaction, possibly with time in between to RBF
+	/// the spending transaction).
+	///
+	/// Default value: 72 (12 hours at an average of 6 blocks/hour).
+	/// Minimum value: [`MIN_CLTV_EXPIRY_DELTA`], any values less than this will be treated as
+	///                [`MIN_CLTV_EXPIRY_DELTA`] instead.
+	///
+	/// [`MIN_CLTV_EXPIRY_DELTA`]: crate::ln::channelmanager::MIN_CLTV_EXPIRY_DELTA
+	pub cltv_expiry_delta: u16,
 }
 
 impl Default for ChannelHandshakeConfig {
@@ -77,6 +97,7 @@ impl Default for ChannelHandshakeConfig {
 			our_htlc_minimum_msat: 1,
 			forwarding_fee_base_msat: 1000,
 			forwarding_fee_proportional_millionths: 0,
+			cltv_expiry_delta: 6 * 12, // 6 blocks/hour * 12 hours
 		}
 	}
 }
@@ -165,26 +186,6 @@ impl Default for ChannelHandshakeLimits {
 /// with our counterparty.
 #[derive(Copy, Clone, Debug)]
 pub struct ChannelConfig {
-	/// The difference in the CLTV value between incoming HTLCs and an outbound HTLC forwarded over
-	/// the channel this config applies to.
-	///
-	/// This is analogous to [`ChannelHandshakeConfig::our_to_self_delay`] but applies to in-flight
-	/// HTLC balance when a channel appears on-chain whereas
-	/// [`ChannelHandshakeConfig::our_to_self_delay`] applies to the remaining
-	/// (non-HTLC-encumbered) balance.
-	///
-	/// Thus, for HTLC-encumbered balances to be enforced on-chain when a channel is force-closed,
-	/// we (or one of our watchtowers) MUST be online to check for broadcast of the current
-	/// commitment transaction at least once per this many blocks (minus some margin to allow us
-	/// enough time to broadcast and confirm a transaction, possibly with time in between to RBF
-	/// the spending transaction).
-	///
-	/// Default value: 72 (12 hours at an average of 6 blocks/hour).
-	/// Minimum value: [`MIN_CLTV_EXPIRY_DELTA`], any values less than this will be treated as
-	///                [`MIN_CLTV_EXPIRY_DELTA`] instead.
-	///
-	/// [`MIN_CLTV_EXPIRY_DELTA`]: crate::ln::channelmanager::MIN_CLTV_EXPIRY_DELTA
-	pub cltv_expiry_delta: u16,
 	/// Set to announce the channel publicly and notify all nodes that they can route via this
 	/// channel.
 	///
@@ -254,7 +255,6 @@ impl Default for ChannelConfig {
 	/// Provides sane defaults for most configurations (but with zero relay fees!).
 	fn default() -> Self {
 		ChannelConfig {
-			cltv_expiry_delta: 6 * 12, // 6 blocks/hour * 12 hours
 			announced_channel: false,
 			commit_upfront_shutdown_pubkey: true,
 			max_dust_htlc_exposure_msat: 5_000_000,
@@ -265,7 +265,6 @@ impl Default for ChannelConfig {
 
 impl_writeable_tlv_based!(ChannelConfig, {
 	(1, max_dust_htlc_exposure_msat, (default_value, 5_000_000)),
-	(2, cltv_expiry_delta, required),
 	(3, force_close_avoidance_max_fee_satoshis, (default_value, 1000)),
 	(4, announced_channel, required),
 	(6, commit_upfront_shutdown_pubkey, required),