From: Matt Corallo Date: Tue, 16 May 2023 20:01:08 +0000 (+0000) Subject: Add a next-outbound-HTLC minimum field to chan details and use it X-Git-Tag: v0.0.116-alpha1~17^2~4 X-Git-Url: http://git.bitcoin.ninja/?a=commitdiff_plain;h=3aa8a1721c6968c6a5b40ffc11d3642646b34ceb;p=rust-lightning Add a next-outbound-HTLC minimum field to chan details and use it In the coming commits, in order to ensure all routes we generate are usable, we'll start calculating the next-HTLC minimum for our channels and using it in the router. Here we set this up by adding an always-0 field for it in `ChannelDetails` and use it when routing. --- diff --git a/fuzz/src/router.rs b/fuzz/src/router.rs index 00c53dfe5..72935f153 100644 --- a/fuzz/src/router.rs +++ b/fuzz/src/router.rs @@ -265,6 +265,7 @@ pub fn do_test(data: &[u8], out: Out) { balance_msat: 0, outbound_capacity_msat: capacity.saturating_mul(1000), next_outbound_htlc_limit_msat: capacity.saturating_mul(1000), + next_outbound_htlc_minimum_msat: 0, inbound_htlc_minimum_msat: None, inbound_htlc_maximum_msat: None, config: None, diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs index 23e56f94b..03acb7330 100644 --- a/lightning/src/ln/channel.rs +++ b/lightning/src/ln/channel.rs @@ -73,6 +73,8 @@ pub struct AvailableBalances { pub outbound_capacity_msat: u64, /// The maximum value we can assign to the next outbound HTLC pub next_outbound_htlc_limit_msat: u64, + /// The minimum value we can assign to the next outbound HTLC + pub next_outbound_htlc_minimum_msat: u64, } #[derive(Debug, Clone, Copy, PartialEq)] @@ -2762,6 +2764,7 @@ impl Channel { 0) as u64, outbound_capacity_msat, next_outbound_htlc_limit_msat: available_capacity_msat, + next_outbound_htlc_minimum_msat: 0, balance_msat, } } diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs index 30eab9066..b5e7d6034 100644 --- a/lightning/src/ln/channelmanager.rs +++ b/lightning/src/ln/channelmanager.rs @@ -1274,8 +1274,14 @@ pub struct ChannelDetails { /// the current state and per-HTLC limit(s). This is intended for use when routing, allowing us /// to use a limit as close as possible to the HTLC limit we can currently send. /// - /// See also [`ChannelDetails::balance_msat`] and [`ChannelDetails::outbound_capacity_msat`]. + /// See also [`ChannelDetails::next_outbound_htlc_minimum_msat`], + /// [`ChannelDetails::balance_msat`], and [`ChannelDetails::outbound_capacity_msat`]. pub next_outbound_htlc_limit_msat: u64, + /// The minimum value for sending a single HTLC to the remote peer. This is the equivalent of + /// [`ChannelDetails::next_outbound_htlc_limit_msat`] but represents a lower-bound, rather than + /// an upper-bound. This is intended for use when routing, allowing us to ensure we pick a + /// route which is valid. + pub next_outbound_htlc_minimum_msat: u64, /// The available inbound capacity for the remote peer to send HTLCs to us. This does not /// include any pending HTLCs which are not yet fully resolved (and, thus, whose balance is not /// available for inclusion in new inbound HTLCs). @@ -1395,6 +1401,7 @@ impl ChannelDetails { inbound_capacity_msat: balance.inbound_capacity_msat, outbound_capacity_msat: balance.outbound_capacity_msat, next_outbound_htlc_limit_msat: balance.next_outbound_htlc_limit_msat, + next_outbound_htlc_minimum_msat: balance.next_outbound_htlc_minimum_msat, user_channel_id: channel.get_user_id(), confirmations_required: channel.minimum_depth(), confirmations: Some(channel.get_funding_tx_confirmations(best_block_height)), @@ -6951,10 +6958,9 @@ impl Writeable for ChannelDetails { (14, user_channel_id_low, required), (16, self.balance_msat, required), (18, self.outbound_capacity_msat, required), - // Note that by the time we get past the required read above, outbound_capacity_msat will be - // filled in, so we can safely unwrap it here. - (19, self.next_outbound_htlc_limit_msat, (default_value, outbound_capacity_msat.0.unwrap() as u64)), + (19, self.next_outbound_htlc_limit_msat, required), (20, self.inbound_capacity_msat, required), + (21, self.next_outbound_htlc_minimum_msat, required), (22, self.confirmations_required, option), (24, self.force_close_spend_delay, option), (26, self.is_outbound, required), @@ -6991,6 +6997,7 @@ impl Readable for ChannelDetails { // filled in, so we can safely unwrap it here. (19, next_outbound_htlc_limit_msat, (default_value, outbound_capacity_msat.0.unwrap() as u64)), (20, inbound_capacity_msat, required), + (21, next_outbound_htlc_minimum_msat, (default_value, 0)), (22, confirmations_required, option), (24, force_close_spend_delay, option), (26, is_outbound, required), @@ -7024,6 +7031,7 @@ impl Readable for ChannelDetails { balance_msat: balance_msat.0.unwrap(), outbound_capacity_msat: outbound_capacity_msat.0.unwrap(), next_outbound_htlc_limit_msat: next_outbound_htlc_limit_msat.0.unwrap(), + next_outbound_htlc_minimum_msat: next_outbound_htlc_minimum_msat.0.unwrap(), inbound_capacity_msat: inbound_capacity_msat.0.unwrap(), confirmations_required, confirmations, diff --git a/lightning/src/routing/router.rs b/lightning/src/routing/router.rs index ef6fef0a7..bf854aed6 100644 --- a/lightning/src/routing/router.rs +++ b/lightning/src/routing/router.rs @@ -929,7 +929,7 @@ impl<'a> CandidateRouteHop<'a> { fn htlc_minimum_msat(&self) -> u64 { match self { - CandidateRouteHop::FirstHop { .. } => 0, + CandidateRouteHop::FirstHop { details } => details.next_outbound_htlc_minimum_msat, CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat, CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0), } @@ -2460,6 +2460,7 @@ mod tests { balance_msat: 0, outbound_capacity_msat, next_outbound_htlc_limit_msat: outbound_capacity_msat, + next_outbound_htlc_minimum_msat: 0, inbound_capacity_msat: 42, unspendable_punishment_reserve: None, confirmations_required: None, @@ -6121,6 +6122,7 @@ pub(crate) mod bench_utils { user_channel_id: 0, balance_msat: 10_000_000_000, outbound_capacity_msat: 10_000_000_000, + next_outbound_htlc_minimum_msat: 0, next_outbound_htlc_limit_msat: 10_000_000_000, inbound_capacity_msat: 0, unspendable_punishment_reserve: None,