X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Futil%2Fconfig.rs;h=b2004df3e9cbd0c043c2b2ef184e538f267ea02a;hb=f961daef33ad1e999c83aafbf654db449e0e93e0;hp=a76f71621011d80b55c02fe898e769055427a808;hpb=e53344663ce58ba0bd04b14f2fce26577de4defb;p=rust-lightning

diff --git a/lightning/src/util/config.rs b/lightning/src/util/config.rs
index a76f7162..b2004df3 100644
--- a/lightning/src/util/config.rs
+++ b/lightning/src/util/config.rs
@@ -126,6 +126,30 @@ pub struct ChannelHandshakeConfig {
 	///
 	/// [`KeysInterface::get_shutdown_scriptpubkey`]: crate::chain::keysinterface::KeysInterface::get_shutdown_scriptpubkey
 	pub commit_upfront_shutdown_pubkey: bool,
+
+	/// The Proportion of the channel value to configure as counterparty's channel reserve,
+	/// i.e., `their_channel_reserve_satoshis` for both outbound and inbound channels.
+	///
+	/// `their_channel_reserve_satoshis` is the minimum balance that the other node has to maintain
+	/// on their side, at all times.
+	/// This ensures that if our counterparty broadcasts a revoked state, we can punish them by
+	/// claiming at least this value on chain.
+	///
+	/// Channel reserve values greater than 30% could be considered highly unreasonable, since that
+	/// amount can never be used for payments.
+	/// Also, if our selected channel reserve for counterparty and counterparty's selected
+	/// channel reserve for us sum up to equal or greater than channel value, channel negotiations
+	/// will fail.
+	///
+	/// Note: Versions of LDK earlier than v0.0.104 will fail to read channels with any channel reserve
+	/// other than the default value.
+	///
+	/// Default value: 1% of channel value, i.e., configured as 10,000 millionths.
+	/// Minimum value: If the calculated proportional value is less than 1000 sats, it will be treated
+	///                as 1000 sats instead, which is a safe implementation-specific lower bound.
+	/// Maximum value: 1,000,000, any values larger than 1 Million will be treated as 1 Million (or 100%)
+	///                instead, although channel negotiations will fail in that case.
+	pub their_channel_reserve_proportional_millionths: u32
 }
 
 impl Default for ChannelHandshakeConfig {
@@ -138,6 +162,7 @@ impl Default for ChannelHandshakeConfig {
 			negotiate_scid_privacy: false,
 			announced_channel: false,
 			commit_upfront_shutdown_pubkey: true,
+			their_channel_reserve_proportional_millionths: 10_000,
 		}
 	}
 }
@@ -249,7 +274,7 @@ impl Default for ChannelHandshakeLimits {
 
 /// Options which apply on a per-channel basis and may change at runtime or based on negotiation
 /// with our counterparty.
-#[derive(Copy, Clone, Debug)]
+#[derive(Copy, Clone, Debug, PartialEq)]
 pub struct ChannelConfig {
 	/// Amount (in millionths of a satoshi) charged per satoshi for payments forwarded outbound
 	/// over the channel.
@@ -300,6 +325,12 @@ pub struct ChannelConfig {
 	/// to such payments may be sustantial if there are many dust HTLCs present when the
 	/// channel is force-closed.
 	///
+	/// The dust threshold for each HTLC is based on the `dust_limit_satoshis` for each party in a
+	/// channel negotiated throughout the channel open process, along with the fees required to have
+	/// a broadcastable HTLC spending transaction. When a channel supports anchor outputs
+	/// (specifically the zero fee HTLC transaction variant), this threshold no longer takes into
+	/// account the HTLC transaction fee as it is zero.
+	///
 	/// This limit is applied for sent, forwarded, and received HTLCs and limits the total
 	/// exposure across all three types per-channel. Setting this too low may prevent the
 	/// sending or receipt of low-value HTLCs on high-traffic nodes, and this limit is very
@@ -345,6 +376,17 @@ impl Default for ChannelConfig {
 	}
 }
 
+impl_writeable_tlv_based!(ChannelConfig, {
+	(0, forwarding_fee_proportional_millionths, required),
+	(2, forwarding_fee_base_msat, required),
+	(4, cltv_expiry_delta, required),
+	(6, max_dust_htlc_exposure_msat, required),
+	// ChannelConfig serialized this field with a required type of 8 prior to the introduction of
+	// LegacyChannelConfig. To make sure that serialization is not compatible with this one, we use
+	// the next required type of 10, which if seen by the old serialization will always fail.
+	(10, force_close_avoidance_max_fee_satoshis, required),
+});
+
 /// Legacy version of [`ChannelConfig`] that stored the static
 /// [`ChannelHandshakeConfig::announced_channel`] and
 /// [`ChannelHandshakeConfig::commit_upfront_shutdown_pubkey`] fields.
@@ -396,9 +438,9 @@ impl ::util::ser::Readable for LegacyChannelConfig {
 		let mut forwarding_fee_base_msat = 0;
 		read_tlv_fields!(reader, {
 			(0, forwarding_fee_proportional_millionths, required),
-			(1, max_dust_htlc_exposure_msat, (default_value, 5_000_000)),
+			(1, max_dust_htlc_exposure_msat, (default_value, 5_000_000u64)),
 			(2, cltv_expiry_delta, required),
-			(3, force_close_avoidance_max_fee_satoshis, (default_value, 1000)),
+			(3, force_close_avoidance_max_fee_satoshis, (default_value, 1000u64)),
 			(4, announced_channel, required),
 			(6, commit_upfront_shutdown_pubkey, required),
 			(8, forwarding_fee_base_msat, required),