From 4f5e17b54d9339469938cb7652f566f9f89410bb Mon Sep 17 00:00:00 2001 From: Matt Corallo Date: Wed, 10 Jul 2024 01:22:32 +0000 Subject: [PATCH] Move blinded path introduction point resolution to a helper method This marginally reduces the size of `get_route` by moving a the blinded path introduction point resolution and blinded path checks into a helper method. --- lightning/src/routing/router.rs | 137 ++++++++++++++++++-------------- 1 file changed, 76 insertions(+), 61 deletions(-) diff --git a/lightning/src/routing/router.rs b/lightning/src/routing/router.rs index 8f299d9ac..da724159a 100644 --- a/lightning/src/routing/router.rs +++ b/lightning/src/routing/router.rs @@ -1635,6 +1635,79 @@ impl<'a> NodeCounters<'a> { } } +/// Calculates the introduction point for each blinded path in the given [`PaymentParameters`], if +/// they can be found. +fn calculate_blinded_path_intro_points<'a, L: Deref>( + payment_params: &PaymentParameters, node_counters: &'a NodeCounters, + network_graph: &ReadOnlyNetworkGraph, logger: &L, our_node_id: NodeId, + first_hop_targets: &HashMap, u32)>, +) -> Result>, LightningError> +where L::Target: Logger { + let introduction_node_id_cache = payment_params.payee.blinded_route_hints().iter() + .map(|(_, path)| { + match &path.introduction_node { + IntroductionNode::NodeId(pubkey) => { + // Note that this will only return `Some` if the `pubkey` is somehow known to + // us (i.e. a channel counterparty or in the network graph). + node_counters.node_counter_from_id(&NodeId::from_pubkey(&pubkey)) + }, + IntroductionNode::DirectedShortChannelId(direction, scid) => { + path.public_introduction_node_id(network_graph) + .map(|node_id_ref| *node_id_ref) + .or_else(|| { + first_hop_targets.iter().find(|(_, (channels, _))| + channels + .iter() + .any(|details| Some(*scid) == details.get_outbound_payment_scid()) + ).map(|(cp, _)| direction.select_node_id(our_node_id, *cp)) + }) + .and_then(|node_id| node_counters.node_counter_from_id(&node_id)) + }, + } + }) + .collect::>(); + match &payment_params.payee { + Payee::Clear { route_hints, node_id, .. } => { + for route in route_hints.iter() { + for hop in &route.0 { + if hop.src_node_id == *node_id { + return Err(LightningError { + err: "Route hint cannot have the payee as the source.".to_owned(), + action: ErrorAction::IgnoreError + }); + } + } + } + }, + Payee::Blinded { route_hints, .. } => { + if introduction_node_id_cache.iter().all(|info_opt| info_opt.map(|(a, _)| a) == Some(&our_node_id)) { + return Err(LightningError{err: "Cannot generate a route to blinded paths if we are the introduction node to all of them".to_owned(), action: ErrorAction::IgnoreError}); + } + for ((_, blinded_path), info_opt) in route_hints.iter().zip(introduction_node_id_cache.iter()) { + if blinded_path.blinded_hops.len() == 0 { + return Err(LightningError{err: "0-hop blinded path provided".to_owned(), action: ErrorAction::IgnoreError}); + } + let introduction_node_id = match info_opt { + None => continue, + Some(info) => info.0, + }; + if *introduction_node_id == our_node_id { + log_info!(logger, "Got blinded path with ourselves as the introduction node, ignoring"); + } else if blinded_path.blinded_hops.len() == 1 && + route_hints + .iter().zip(introduction_node_id_cache.iter()) + .filter(|((_, p), _)| p.blinded_hops.len() == 1) + .any(|(_, iter_info_opt)| iter_info_opt.is_some() && iter_info_opt != info_opt) + { + return Err(LightningError{err: format!("1-hop blinded paths must all have matching introduction node ids"), action: ErrorAction::IgnoreError}); + } + } + } + } + + Ok(introduction_node_id_cache) +} + #[inline] fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 { let saturation_shift: u32 = max_channel_saturation_power_of_half as u32; @@ -2183,67 +2256,9 @@ where L::Target: Logger { let node_counters = node_counter_builder.build(); - let introduction_node_id_cache = payment_params.payee.blinded_route_hints().iter() - .map(|(_, path)| { - match &path.introduction_node { - IntroductionNode::NodeId(pubkey) => { - // Note that this will only return `Some` if the `pubkey` is somehow known to - // us (i.e. a channel counterparty or in the network graph). - node_counters.node_counter_from_id(&NodeId::from_pubkey(&pubkey)) - }, - IntroductionNode::DirectedShortChannelId(direction, scid) => { - path.public_introduction_node_id(network_graph) - .map(|node_id_ref| *node_id_ref) - .or_else(|| { - first_hop_targets.iter().find(|(_, (channels, _))| - channels - .iter() - .any(|details| Some(*scid) == details.get_outbound_payment_scid()) - ).map(|(cp, _)| direction.select_node_id(our_node_id, *cp)) - }) - .and_then(|node_id| node_counters.node_counter_from_id(&node_id)) - }, - } - }) - .collect::>(); - match &payment_params.payee { - Payee::Clear { route_hints, node_id, .. } => { - for route in route_hints.iter() { - for hop in &route.0 { - if hop.src_node_id == *node_id { - return Err(LightningError { - err: "Route hint cannot have the payee as the source.".to_owned(), - action: ErrorAction::IgnoreError - }); - } - } - } - }, - Payee::Blinded { route_hints, .. } => { - if introduction_node_id_cache.iter().all(|info_opt| info_opt.map(|(a, _)| a) == Some(&our_node_id)) { - return Err(LightningError{err: "Cannot generate a route to blinded paths if we are the introduction node to all of them".to_owned(), action: ErrorAction::IgnoreError}); - } - for ((_, blinded_path), info_opt) in route_hints.iter().zip(introduction_node_id_cache.iter()) { - if blinded_path.blinded_hops.len() == 0 { - return Err(LightningError{err: "0-hop blinded path provided".to_owned(), action: ErrorAction::IgnoreError}); - } - let introduction_node_id = match info_opt { - None => continue, - Some(info) => info.0, - }; - if *introduction_node_id == our_node_id { - log_info!(logger, "Got blinded path with ourselves as the introduction node, ignoring"); - } else if blinded_path.blinded_hops.len() == 1 && - route_hints - .iter().zip(introduction_node_id_cache.iter()) - .filter(|((_, p), _)| p.blinded_hops.len() == 1) - .any(|(_, iter_info_opt)| iter_info_opt.is_some() && iter_info_opt != info_opt) - { - return Err(LightningError{err: format!("1-hop blinded paths must all have matching introduction node ids"), action: ErrorAction::IgnoreError}); - } - } - } - } + let introduction_node_id_cache = calculate_blinded_path_intro_points( + &payment_params, &node_counters, network_graph, &logger, our_node_id, &first_hop_targets, + )?; // The main heap containing all candidate next-hops sorted by their score (max(fee, // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of -- 2.39.5