From a1b3fbb6fe626c769c1664545449caa2dc4ec2e4 Mon Sep 17 00:00:00 2001 From: Valentine Wallace Date: Thu, 7 Sep 2023 17:11:30 -0400 Subject: [PATCH] Struct-ify blinded payment path intermediate node info --- lightning/src/blinded_path/mod.rs | 7 +- lightning/src/blinded_path/payment.rs | 249 +++++++++++++++----------- 2 files changed, 149 insertions(+), 107 deletions(-) diff --git a/lightning/src/blinded_path/mod.rs b/lightning/src/blinded_path/mod.rs index 82d50546ddd..927bbea9f6e 100644 --- a/lightning/src/blinded_path/mod.rs +++ b/lightning/src/blinded_path/mod.rs @@ -76,8 +76,7 @@ impl BlindedPath { }) } - /// Create a blinded path for a payment, to be forwarded along `intermediate_nodes`, where each - /// node is composed of `(node_id, tlvs, htlc_maximum_msat)`. + /// Create a blinded path for a payment, to be forwarded along `intermediate_nodes`. /// /// Errors if: /// * a provided node id is invalid @@ -87,7 +86,7 @@ impl BlindedPath { /// [`ForwardTlvs`]: crate::blinded_path::payment::ForwardTlvs // TODO: make all payloads the same size with padding + add dummy hops pub fn new_for_payment( - intermediate_nodes: &[(PublicKey, payment::ForwardTlvs, u64)], payee_node_id: PublicKey, + intermediate_nodes: &[payment::ForwardNode], payee_node_id: PublicKey, payee_tlvs: payment::ReceiveTlvs, htlc_maximum_msat: u64, entropy_source: &ES, secp_ctx: &Secp256k1 ) -> Result<(BlindedPayInfo, Self), ()> { @@ -96,7 +95,7 @@ impl BlindedPath { let blinded_payinfo = payment::compute_payinfo(intermediate_nodes, &payee_tlvs, htlc_maximum_msat)?; Ok((blinded_payinfo, BlindedPath { - introduction_node_id: intermediate_nodes.first().map_or(payee_node_id, |n| n.0), + introduction_node_id: intermediate_nodes.first().map_or(payee_node_id, |n| n.node_id), blinding_point: PublicKey::from_secret_key(secp_ctx, &blinding_secret), blinded_hops: payment::blinded_hops( secp_ctx, intermediate_nodes, payee_node_id, payee_tlvs, &blinding_secret diff --git a/lightning/src/blinded_path/payment.rs b/lightning/src/blinded_path/payment.rs index 84fdac7fdee..957d79796c1 100644 --- a/lightning/src/blinded_path/payment.rs +++ b/lightning/src/blinded_path/payment.rs @@ -16,6 +16,18 @@ use crate::util::ser::{Readable, Writeable, Writer}; use core::convert::TryFrom; +/// An intermediate node, its outbound channel, and relay parameters. +#[derive(Clone, Debug)] +pub struct ForwardNode { + /// The TLVs for this node's [`BlindedHop`], where the fee parameters contained within are also + /// used for [`BlindedPayInfo`] construction. + pub tlvs: ForwardTlvs, + /// This node's pubkey. + pub node_id: PublicKey, + /// The maximum value, in msat, that may be accepted by this node. + pub htlc_maximum_msat: u64, +} + /// Data to construct a [`BlindedHop`] for forwarding a payment. #[derive(Clone, Debug)] pub struct ForwardTlvs { @@ -150,12 +162,12 @@ impl Readable for BlindedPaymentTlvs { /// Construct blinded payment hops for the given `intermediate_nodes` and payee info. pub(super) fn blinded_hops( - secp_ctx: &Secp256k1, intermediate_nodes: &[(PublicKey, ForwardTlvs, u64)], + secp_ctx: &Secp256k1, intermediate_nodes: &[ForwardNode], payee_node_id: PublicKey, payee_tlvs: ReceiveTlvs, session_priv: &SecretKey ) -> Result, secp256k1::Error> { - let pks = intermediate_nodes.iter().map(|(pk, _, _)| pk) + let pks = intermediate_nodes.iter().map(|node| &node.node_id) .chain(core::iter::once(&payee_node_id)); - let tlvs = intermediate_nodes.iter().map(|(_, tlvs, _)| BlindedPaymentTlvsRef::Forward(tlvs)) + let tlvs = intermediate_nodes.iter().map(|node| BlindedPaymentTlvsRef::Forward(&node.tlvs)) .chain(core::iter::once(BlindedPaymentTlvsRef::Receive(&payee_tlvs))); utils::construct_blinded_hops(secp_ctx, pks, tlvs, session_priv) } @@ -182,13 +194,12 @@ fn amt_to_forward_msat(inbound_amt_msat: u64, payment_relay: &PaymentRelay) -> O } pub(super) fn compute_payinfo( - intermediate_nodes: &[(PublicKey, ForwardTlvs, u64)], payee_tlvs: &ReceiveTlvs, - payee_htlc_maximum_msat: u64 + intermediate_nodes: &[ForwardNode], payee_tlvs: &ReceiveTlvs, payee_htlc_maximum_msat: u64 ) -> Result { let mut curr_base_fee: u64 = 0; let mut curr_prop_mil: u64 = 0; let mut cltv_expiry_delta: u16 = 0; - for (_, tlvs, _) in intermediate_nodes.iter().rev() { + for tlvs in intermediate_nodes.iter().rev().map(|n| &n.tlvs) { // In the future, we'll want to take the intersection of all supported features for the // `BlindedPayInfo`, but there are no features in that context right now. if tlvs.features.requires_unknown_bits_from(&BlindedHopFeatures::empty()) { return Err(()) } @@ -216,16 +227,16 @@ pub(super) fn compute_payinfo( let mut htlc_minimum_msat: u64 = 1; let mut htlc_maximum_msat: u64 = 21_000_000 * 100_000_000 * 1_000; // Total bitcoin supply - for (_, tlvs, max_htlc_candidate) in intermediate_nodes.iter() { + for node in intermediate_nodes.iter() { // The min htlc for an intermediate node is that node's min minus the fees charged by all of the // following hops for forwarding that min, since that fee amount will automatically be included // in the amount that this node receives and contribute towards reaching its min. htlc_minimum_msat = amt_to_forward_msat( - core::cmp::max(tlvs.payment_constraints.htlc_minimum_msat, htlc_minimum_msat), - &tlvs.payment_relay + core::cmp::max(node.tlvs.payment_constraints.htlc_minimum_msat, htlc_minimum_msat), + &node.tlvs.payment_relay ).unwrap_or(1); // If underflow occurs, we definitely reached this node's min htlc_maximum_msat = amt_to_forward_msat( - core::cmp::min(*max_htlc_candidate, htlc_maximum_msat), &tlvs.payment_relay + core::cmp::min(node.htlc_maximum_msat, htlc_maximum_msat), &node.tlvs.payment_relay ).ok_or(())?; // If underflow occurs, we cannot send to this hop without exceeding their max } htlc_minimum_msat = core::cmp::max( @@ -258,7 +269,7 @@ impl_writeable_msg!(PaymentConstraints, { #[cfg(test)] mod tests { use bitcoin::secp256k1::PublicKey; - use crate::blinded_path::payment::{ForwardTlvs, ReceiveTlvs, PaymentConstraints, PaymentRelay}; + use crate::blinded_path::payment::{ForwardNode, ForwardTlvs, ReceiveTlvs, PaymentConstraints, PaymentRelay}; use crate::ln::PaymentSecret; use crate::ln::features::BlindedHopFeatures; @@ -267,31 +278,39 @@ mod tests { // Taken from the spec example for aggregating blinded payment info. See // https://github.com/lightning/bolts/blob/master/proposals/route-blinding.md#blinded-payments let dummy_pk = PublicKey::from_slice(&[2; 33]).unwrap(); - let intermediate_nodes = vec![(dummy_pk, ForwardTlvs { - short_channel_id: 0, - payment_relay: PaymentRelay { - cltv_expiry_delta: 144, - fee_proportional_millionths: 500, - fee_base_msat: 100, - }, - payment_constraints: PaymentConstraints { - max_cltv_expiry: 0, - htlc_minimum_msat: 100, + let intermediate_nodes = vec![ForwardNode { + node_id: dummy_pk, + tlvs: ForwardTlvs { + short_channel_id: 0, + payment_relay: PaymentRelay { + cltv_expiry_delta: 144, + fee_proportional_millionths: 500, + fee_base_msat: 100, + }, + payment_constraints: PaymentConstraints { + max_cltv_expiry: 0, + htlc_minimum_msat: 100, + }, + features: BlindedHopFeatures::empty(), }, - features: BlindedHopFeatures::empty(), - }, u64::max_value()), (dummy_pk, ForwardTlvs { - short_channel_id: 0, - payment_relay: PaymentRelay { - cltv_expiry_delta: 144, - fee_proportional_millionths: 500, - fee_base_msat: 100, + htlc_maximum_msat: u64::max_value(), + }, ForwardNode { + node_id: dummy_pk, + tlvs: ForwardTlvs { + short_channel_id: 0, + payment_relay: PaymentRelay { + cltv_expiry_delta: 144, + fee_proportional_millionths: 500, + fee_base_msat: 100, + }, + payment_constraints: PaymentConstraints { + max_cltv_expiry: 0, + htlc_minimum_msat: 1_000, + }, + features: BlindedHopFeatures::empty(), }, - payment_constraints: PaymentConstraints { - max_cltv_expiry: 0, - htlc_minimum_msat: 1_000, - }, - features: BlindedHopFeatures::empty(), - }, u64::max_value())]; + htlc_maximum_msat: u64::max_value(), + }]; let recv_tlvs = ReceiveTlvs { payment_secret: PaymentSecret([0; 32]), payment_constraints: PaymentConstraints { @@ -330,31 +349,39 @@ mod tests { // If no hops charge fees, the htlc_minimum_msat should just be the maximum htlc_minimum_msat // along the path. let dummy_pk = PublicKey::from_slice(&[2; 33]).unwrap(); - let intermediate_nodes = vec![(dummy_pk, ForwardTlvs { - short_channel_id: 0, - payment_relay: PaymentRelay { - cltv_expiry_delta: 0, - fee_proportional_millionths: 0, - fee_base_msat: 0, + let intermediate_nodes = vec![ForwardNode { + node_id: dummy_pk, + tlvs: ForwardTlvs { + short_channel_id: 0, + payment_relay: PaymentRelay { + cltv_expiry_delta: 0, + fee_proportional_millionths: 0, + fee_base_msat: 0, + }, + payment_constraints: PaymentConstraints { + max_cltv_expiry: 0, + htlc_minimum_msat: 1, + }, + features: BlindedHopFeatures::empty(), }, - payment_constraints: PaymentConstraints { - max_cltv_expiry: 0, - htlc_minimum_msat: 1, - }, - features: BlindedHopFeatures::empty(), - }, u64::max_value()), (dummy_pk, ForwardTlvs { - short_channel_id: 0, - payment_relay: PaymentRelay { - cltv_expiry_delta: 0, - fee_proportional_millionths: 0, - fee_base_msat: 0, - }, - payment_constraints: PaymentConstraints { - max_cltv_expiry: 0, - htlc_minimum_msat: 2_000, + htlc_maximum_msat: u64::max_value() + }, ForwardNode { + node_id: dummy_pk, + tlvs: ForwardTlvs { + short_channel_id: 0, + payment_relay: PaymentRelay { + cltv_expiry_delta: 0, + fee_proportional_millionths: 0, + fee_base_msat: 0, + }, + payment_constraints: PaymentConstraints { + max_cltv_expiry: 0, + htlc_minimum_msat: 2_000, + }, + features: BlindedHopFeatures::empty(), }, - features: BlindedHopFeatures::empty(), - }, u64::max_value())]; + htlc_maximum_msat: u64::max_value() + }]; let recv_tlvs = ReceiveTlvs { payment_secret: PaymentSecret([0; 32]), payment_constraints: PaymentConstraints { @@ -372,31 +399,39 @@ mod tests { // Create a path with varying fees and htlc_mins, and make sure htlc_minimum_msat ends up as the // max (htlc_min - following_fees) along the path. let dummy_pk = PublicKey::from_slice(&[2; 33]).unwrap(); - let intermediate_nodes = vec![(dummy_pk, ForwardTlvs { - short_channel_id: 0, - payment_relay: PaymentRelay { - cltv_expiry_delta: 0, - fee_proportional_millionths: 500, - fee_base_msat: 1_000, - }, - payment_constraints: PaymentConstraints { - max_cltv_expiry: 0, - htlc_minimum_msat: 5_000, + let intermediate_nodes = vec![ForwardNode { + node_id: dummy_pk, + tlvs: ForwardTlvs { + short_channel_id: 0, + payment_relay: PaymentRelay { + cltv_expiry_delta: 0, + fee_proportional_millionths: 500, + fee_base_msat: 1_000, + }, + payment_constraints: PaymentConstraints { + max_cltv_expiry: 0, + htlc_minimum_msat: 5_000, + }, + features: BlindedHopFeatures::empty(), }, - features: BlindedHopFeatures::empty(), - }, u64::max_value()), (dummy_pk, ForwardTlvs { - short_channel_id: 0, - payment_relay: PaymentRelay { - cltv_expiry_delta: 0, - fee_proportional_millionths: 500, - fee_base_msat: 200, + htlc_maximum_msat: u64::max_value() + }, ForwardNode { + node_id: dummy_pk, + tlvs: ForwardTlvs { + short_channel_id: 0, + payment_relay: PaymentRelay { + cltv_expiry_delta: 0, + fee_proportional_millionths: 500, + fee_base_msat: 200, + }, + payment_constraints: PaymentConstraints { + max_cltv_expiry: 0, + htlc_minimum_msat: 2_000, + }, + features: BlindedHopFeatures::empty(), }, - payment_constraints: PaymentConstraints { - max_cltv_expiry: 0, - htlc_minimum_msat: 2_000, - }, - features: BlindedHopFeatures::empty(), - }, u64::max_value())]; + htlc_maximum_msat: u64::max_value() + }]; let recv_tlvs = ReceiveTlvs { payment_secret: PaymentSecret([0; 32]), payment_constraints: PaymentConstraints { @@ -418,31 +453,39 @@ mod tests { // Create a path with varying fees and `htlc_maximum_msat`s, and make sure the aggregated max // htlc ends up as the min (htlc_max - following_fees) along the path. let dummy_pk = PublicKey::from_slice(&[2; 33]).unwrap(); - let intermediate_nodes = vec![(dummy_pk, ForwardTlvs { - short_channel_id: 0, - payment_relay: PaymentRelay { - cltv_expiry_delta: 0, - fee_proportional_millionths: 500, - fee_base_msat: 1_000, + let intermediate_nodes = vec![ForwardNode { + node_id: dummy_pk, + tlvs: ForwardTlvs { + short_channel_id: 0, + payment_relay: PaymentRelay { + cltv_expiry_delta: 0, + fee_proportional_millionths: 500, + fee_base_msat: 1_000, + }, + payment_constraints: PaymentConstraints { + max_cltv_expiry: 0, + htlc_minimum_msat: 1, + }, + features: BlindedHopFeatures::empty(), }, - payment_constraints: PaymentConstraints { - max_cltv_expiry: 0, - htlc_minimum_msat: 1, - }, - features: BlindedHopFeatures::empty(), - }, 5_000), (dummy_pk, ForwardTlvs { - short_channel_id: 0, - payment_relay: PaymentRelay { - cltv_expiry_delta: 0, - fee_proportional_millionths: 500, - fee_base_msat: 1, - }, - payment_constraints: PaymentConstraints { - max_cltv_expiry: 0, - htlc_minimum_msat: 1, + htlc_maximum_msat: 5_000, + }, ForwardNode { + node_id: dummy_pk, + tlvs: ForwardTlvs { + short_channel_id: 0, + payment_relay: PaymentRelay { + cltv_expiry_delta: 0, + fee_proportional_millionths: 500, + fee_base_msat: 1, + }, + payment_constraints: PaymentConstraints { + max_cltv_expiry: 0, + htlc_minimum_msat: 1, + }, + features: BlindedHopFeatures::empty(), }, - features: BlindedHopFeatures::empty(), - }, 10_000)]; + htlc_maximum_msat: 10_000 + }]; let recv_tlvs = ReceiveTlvs { payment_secret: PaymentSecret([0; 32]), payment_constraints: PaymentConstraints {