+// This file is Copyright its original authors, visible in version control
+// history.
+//
+// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
+// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
+// You may not use this file except in accordance with one or both of these
+// licenses.
+
//! Various user-configurable channel limits and settings which ChannelManager
//! applies for you.
use ln::channelmanager::{BREAKDOWN_TIMEOUT, MAX_LOCAL_BREAKDOWN_TIMEOUT};
-/// Top-level config which holds ChannelHandshakeLimits and ChannelConfig.
-///
-/// Default::default() provides sane defaults for most configurations
-/// (but currently with 0 relay fees!)
-#[derive(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 config which affects behavior during channel lifetime.
- pub channel_options: ChannelConfig,
-}
-
-impl Default for UserConfig {
- fn default() -> Self {
- UserConfig {
- own_channel_config: ChannelHandshakeConfig::default(),
- peer_channel_config_limits: ChannelHandshakeLimits::default(),
- channel_options: ChannelConfig::default(),
- }
- }
-}
-
/// Configuration we set when applicable.
///
/// Default::default() provides sane defaults.
-#[derive(Clone, Debug)]
+#[derive(Copy, Clone, Debug)]
pub struct ChannelHandshakeConfig {
/// Confirmations we will wait for before considering the channel locked in.
/// Applied only for inbound channels (see ChannelHandshakeLimits::max_minimum_depth for the
///
/// Default value: 6.
pub minimum_depth: u32,
- /// Set to the amount of time we require our counterparty to wait to claim their money.
+ /// Set to the number of blocks we require our counterparty to wait to claim their money (ie
+ /// the number of blocks we have to punish our counterparty if they broadcast a revoked
+ /// transaction).
///
- /// It's one of the main parameter of our security model. We (or one of our watchtowers) MUST
- /// be online to check for peer having broadcast a revoked transaction to steal our funds
- /// at least once every our_to_self_delay blocks.
+ /// This is one of the main parameters of our security model. We (or one of our watchtowers) MUST
+ /// be online to check for revoked transactions on-chain at least once every our_to_self_delay
+ /// 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).
///
/// Meanwhile, asking for a too high delay, we bother peer to freeze funds for nothing in
/// case of an honest unilateral channel close, which implicitly decrease the economic value of
/// our channel.
///
- /// Default value: BREAKDOWN_TIMEOUT (currently 144), we enforce it as a minimum at channel
- /// opening so you can tweak config to ask for more security, not less.
+ /// Default value: [`BREAKDOWN_TIMEOUT`], we enforce it as a minimum at channel opening so you
+ /// can tweak config to ask for more security, not less.
pub our_to_self_delay: u16,
/// Set to the smallest value HTLC we will accept to process.
///
///
/// Default value: 0.
pub min_max_accepted_htlcs: u16,
- /// Outputs below a certain value will not be added to on-chain transactions. The dust value is
- /// required to always be higher than this value so this only applies to HTLC outputs (and
- /// potentially to-self outputs before any payments have been made).
- /// Thus, HTLCs below this amount plus HTLC transaction fees are not enforceable on-chain.
- /// This setting allows you to set a minimum dust limit for their commitment transactions,
- /// reflecting the reality that tiny outputs are not considered standard transactions and will
- /// not propagate through the Bitcoin network.
- ///
- /// Default value: 546, the current dust limit on the Bitcoin network.
- pub min_dust_limit_satoshis: u64,
- /// Maximum allowed threshold above which outputs will not be generated in their commitment
- /// transactions.
- /// HTLCs below this amount plus HTLC transaction fees are not enforceable on-chain.
- ///
- /// Default value: u64::max_value.
- pub max_dust_limit_satoshis: u64,
/// Before a channel is usable the funding transaction will need to be confirmed by at least a
/// certain number of blocks, specified by the node which is not the funder (as the funder can
/// assume they aren't going to double-spend themselves).
/// Not checking this value would be a security issue, as our peer would be able to set it to
/// max relative lock-time (a year) and we would "lose" money as it would be locked for a long time.
///
- /// Default value: MAX_LOCAL_BREAKDOWN_TIMEOUT (1008), which we also enforce as a maximum value
- /// so you can tweak config to reduce the loss of having useless locked funds (if your peer accepts)
+ /// Default value: 2016, which we also enforce as a maximum value so you can tweak config to
+ /// reduce the loss of having useless locked funds (if your peer accepts)
pub their_to_self_delay: u16
}
min_max_htlc_value_in_flight_msat: 0,
max_channel_reserve_satoshis: <u64>::max_value(),
min_max_accepted_htlcs: 0,
- min_dust_limit_satoshis: 546,
- max_dust_limit_satoshis: <u64>::max_value(),
max_minimum_depth: 144,
force_announced_channel_preference: true,
their_to_self_delay: MAX_LOCAL_BREAKDOWN_TIMEOUT,
///
/// Default value: 0.
pub fee_proportional_millionths: 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,
/// Set to announce the channel publicly and notify all nodes that they can route via this
/// channel.
///
fn default() -> Self {
ChannelConfig {
fee_proportional_millionths: 0,
+ cltv_expiry_delta: 6 * 12, // 6 blocks/hour * 12 hours
announced_channel: false,
commit_upfront_shutdown_pubkey: true,
}
}
}
-//Add write and readable traits to channelconfig
-impl_writeable!(ChannelConfig, 8+1+1, {
- fee_proportional_millionths,
- announced_channel,
- commit_upfront_shutdown_pubkey
+impl_writeable_tlv_based!(ChannelConfig, {
+ (0, fee_proportional_millionths, required),
+ (2, cltv_expiry_delta, required),
+ (4, announced_channel, required),
+ (6, commit_upfront_shutdown_pubkey, required),
});
+
+/// Top-level config which holds ChannelHandshakeLimits and ChannelConfig.
+///
+/// Default::default() provides sane defaults for most configurations
+/// (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 config which affects behavior during channel lifetime.
+ pub channel_options: ChannelConfig,
+}
+
+impl Default for UserConfig {
+ fn default() -> Self {
+ UserConfig {
+ own_channel_config: ChannelHandshakeConfig::default(),
+ peer_channel_config_limits: ChannelHandshakeLimits::default(),
+ channel_options: ChannelConfig::default(),
+ }
+ }
+}
projects / rust-lightning / blobdiff