Merge pull request #1957 from TheBlueMatt/2022-01-mon-ref-lockorder
[rust-lightning] / lightning / src / util / config.rs
index 570e570a893e9583e4bb57ca18d4cb7c515a581c..18bba29fef414434b1fe4df2215e1dd59cbc3e7c 100644 (file)
@@ -10,8 +10,8 @@
 //! Various user-configurable channel limits and settings which ChannelManager
 //! applies for you.
 
-use ln::channel::MAX_FUNDING_SATOSHIS_NO_WUMBO;
-use ln::channelmanager::{BREAKDOWN_TIMEOUT, MAX_LOCAL_BREAKDOWN_TIMEOUT};
+use crate::ln::channel::MAX_FUNDING_SATOSHIS_NO_WUMBO;
+use crate::ln::channelmanager::{BREAKDOWN_TIMEOUT, MAX_LOCAL_BREAKDOWN_TIMEOUT};
 
 /// Configuration we set when applicable.
 ///
@@ -120,12 +120,36 @@ pub struct ChannelHandshakeConfig {
        /// any attacker who is able to take control of a channel can just as easily send the funds via
        /// lightning payments, so we never require that our counterparties support this option.
        ///
-       /// The upfront key committed is provided from [`KeysInterface::get_shutdown_scriptpubkey`].
+       /// The upfront key committed is provided from [`SignerProvider::get_shutdown_scriptpubkey`].
        ///
        /// Default value: true.
        ///
-       /// [`KeysInterface::get_shutdown_scriptpubkey`]: crate::chain::keysinterface::KeysInterface::get_shutdown_scriptpubkey
+       /// [`SignerProvider::get_shutdown_scriptpubkey`]: crate::chain::keysinterface::SignerProvider::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,
                }
        }
 }
@@ -146,7 +171,7 @@ impl Default for ChannelHandshakeConfig {
 ///
 /// These limits are only applied to our counterparty's limits, not our own.
 ///
-/// Use 0/<type>::max_value() as appropriate to skip checking.
+/// Use 0/`<type>::max_value()` as appropriate to skip checking.
 ///
 /// Provides sane defaults for most configurations.
 ///
@@ -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, Eq)]
 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
@@ -345,12 +376,23 @@ 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.
 #[derive(Copy, Clone, Debug)]
 pub(crate) struct LegacyChannelConfig {
-       pub(crate) mutable: ChannelConfig,
+       pub(crate) options: ChannelConfig,
        /// Deprecated but may still be read from. See [`ChannelHandshakeConfig::announced_channel`] to
        /// set this when opening/accepting a channel.
        pub(crate) announced_channel: bool,
@@ -363,30 +405,30 @@ pub(crate) struct LegacyChannelConfig {
 impl Default for LegacyChannelConfig {
        fn default() -> Self {
                Self {
-                       mutable: ChannelConfig::default(),
+                       options: ChannelConfig::default(),
                        announced_channel: false,
                        commit_upfront_shutdown_pubkey: true,
                }
        }
 }
 
-impl ::util::ser::Writeable for LegacyChannelConfig {
-       fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), ::io::Error> {
+impl crate::util::ser::Writeable for LegacyChannelConfig {
+       fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), crate::io::Error> {
                write_tlv_fields!(writer, {
-                       (0, self.mutable.forwarding_fee_proportional_millionths, required),
-                       (1, self.mutable.max_dust_htlc_exposure_msat, (default_value, 5_000_000)),
-                       (2, self.mutable.cltv_expiry_delta, required),
-                       (3, self.mutable.force_close_avoidance_max_fee_satoshis, (default_value, 1000)),
+                       (0, self.options.forwarding_fee_proportional_millionths, required),
+                       (1, self.options.max_dust_htlc_exposure_msat, (default_value, 5_000_000)),
+                       (2, self.options.cltv_expiry_delta, required),
+                       (3, self.options.force_close_avoidance_max_fee_satoshis, (default_value, 1000)),
                        (4, self.announced_channel, required),
                        (6, self.commit_upfront_shutdown_pubkey, required),
-                       (8, self.mutable.forwarding_fee_base_msat, required),
+                       (8, self.options.forwarding_fee_base_msat, required),
                });
                Ok(())
        }
 }
 
-impl ::util::ser::Readable for LegacyChannelConfig {
-       fn read<R: ::io::Read>(reader: &mut R) -> Result<Self, ::ln::msgs::DecodeError> {
+impl crate::util::ser::Readable for LegacyChannelConfig {
+       fn read<R: crate::io::Read>(reader: &mut R) -> Result<Self, crate::ln::msgs::DecodeError> {
                let mut forwarding_fee_proportional_millionths = 0;
                let mut max_dust_htlc_exposure_msat = 5_000_000;
                let mut cltv_expiry_delta = 0;
@@ -396,15 +438,15 @@ 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),
                });
                Ok(Self {
-                       mutable: ChannelConfig {
+                       options: ChannelConfig {
                                forwarding_fee_proportional_millionths,
                                max_dust_htlc_exposure_msat,
                                cltv_expiry_delta,
@@ -423,12 +465,12 @@ impl ::util::ser::Readable for LegacyChannelConfig {
 /// (but currently with 0 relay fees!)
 #[derive(Copy, Clone, Debug)]
 pub struct UserConfig {
-       /// Channel config that we propose to our counterparty.
-       pub own_channel_config: ChannelHandshakeConfig,
-       /// Limits applied to our counterparty's proposed channel config settings.
-       pub peer_channel_config_limits: ChannelHandshakeLimits,
+       /// Channel handshake config that we propose to our counterparty.
+       pub channel_handshake_config: ChannelHandshakeConfig,
+       /// Limits applied to our counterparty's proposed channel handshake config settings.
+       pub channel_handshake_limits: ChannelHandshakeLimits,
        /// Channel config which affects behavior during channel lifetime.
-       pub channel_options: ChannelConfig,
+       pub channel_config: ChannelConfig,
        /// If this is set to false, we will reject any HTLCs which were to be forwarded over private
        /// channels. This prevents us from taking on HTLC-forwarding risk when we intend to run as a
        /// node which is not online reliably.
@@ -463,17 +505,29 @@ pub struct UserConfig {
        /// [`msgs::OpenChannel`]: crate::ln::msgs::OpenChannel
        /// [`msgs::AcceptChannel`]: crate::ln::msgs::AcceptChannel
        pub manually_accept_inbound_channels: bool,
+       ///  If this is set to true, LDK will intercept HTLCs that are attempting to be forwarded over
+       ///  fake short channel ids generated via [`ChannelManager::get_intercept_scid`]. Upon HTLC
+       ///  intercept, LDK will generate an [`Event::HTLCIntercepted`] which MUST be handled by the user.
+       ///
+       ///  Setting this to true may break backwards compatibility with LDK versions < 0.0.113.
+       ///
+       ///  Default value: false.
+       ///
+       /// [`ChannelManager::get_intercept_scid`]: crate::ln::channelmanager::ChannelManager::get_intercept_scid
+       /// [`Event::HTLCIntercepted`]: crate::util::events::Event::HTLCIntercepted
+       pub accept_intercept_htlcs: bool,
 }
 
 impl Default for UserConfig {
        fn default() -> Self {
                UserConfig {
-                       own_channel_config: ChannelHandshakeConfig::default(),
-                       peer_channel_config_limits: ChannelHandshakeLimits::default(),
-                       channel_options: ChannelConfig::default(),
+                       channel_handshake_config: ChannelHandshakeConfig::default(),
+                       channel_handshake_limits: ChannelHandshakeLimits::default(),
+                       channel_config: ChannelConfig::default(),
                        accept_forwards_to_priv_channels: false,
                        accept_inbound_channels: true,
                        manually_accept_inbound_channels: false,
+                       accept_intercept_htlcs: false,
                }
        }
 }