From 606304aa32f4d767f2049a5fdff9e5236e3aa5e7 Mon Sep 17 00:00:00 2001 From: Jeffrey Czyz Date: Fri, 3 Mar 2023 09:38:45 -0600 Subject: [PATCH] Multi-hop blinded paths in ChannelManager When constructing blinded paths for Offer and Refund, delegate to MessageRouter::create_blinded_paths which may produce multi-hop blinded paths. Fallback to one-hop blinded paths if the MessageRouter fails or returns no paths. Likewise, do the same for InvoiceRequest and Bolt12Invoice reply paths. --- lightning/src/ln/channelmanager.rs | 80 ++++++++++++++++++++---------- 1 file changed, 55 insertions(+), 25 deletions(-) diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs index dccc53ae8..e9c6a197e 100644 --- a/lightning/src/ln/channelmanager.rs +++ b/lightning/src/ln/channelmanager.rs @@ -65,7 +65,7 @@ use crate::offers::merkle::SignError; use crate::offers::offer::{DerivedMetadata, Offer, OfferBuilder}; use crate::offers::parse::Bolt12SemanticError; use crate::offers::refund::{Refund, RefundBuilder}; -use crate::onion_message::{Destination, OffersMessage, OffersMessageHandler, PendingOnionMessage, new_pending_onion_message}; +use crate::onion_message::{Destination, MessageRouter, OffersMessage, OffersMessageHandler, PendingOnionMessage, new_pending_onion_message}; use crate::sign::{EntropySource, KeysManager, NodeSigner, Recipient, SignerProvider}; use crate::sign::ecdsa::WriteableEcdsaChannelSigner; use crate::util::config::{UserConfig, ChannelConfig, ChannelConfigUpdate}; @@ -7483,32 +7483,43 @@ where /// /// # Privacy /// - /// Uses a one-hop [`BlindedPath`] for the offer with [`ChannelManager::get_our_node_id`] as the - /// introduction node and a derived signing pubkey for recipient privacy. As such, currently, - /// the node must be announced. Otherwise, there is no way to find a path to the introduction - /// node in order to send the [`InvoiceRequest`]. + /// Uses [`MessageRouter::create_blinded_paths`] to construct a [`BlindedPath`] for the offer. + /// However, if one is not found, uses a one-hop [`BlindedPath`] with + /// [`ChannelManager::get_our_node_id`] as the introduction node instead. In the latter case, + /// the node must be announced, otherwise, there is no way to find a path to the introduction in + /// order to send the [`InvoiceRequest`]. + /// + /// Also, uses a derived signing pubkey in the offer for recipient privacy. /// /// # Limitations /// /// Requires a direct connection to the introduction node in the responding [`InvoiceRequest`]'s /// reply path. /// + /// # Errors + /// + /// Errors if the parameterized [`Router`] is unable to create a blinded path for the offer. + /// /// This is not exported to bindings users as builder patterns don't map outside of move semantics. /// /// [`Offer`]: crate::offers::offer::Offer /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest pub fn create_offer_builder( &self, description: String - ) -> OfferBuilder { + ) -> Result, Bolt12SemanticError> { let node_id = self.get_our_node_id(); let expanded_key = &self.inbound_payment_key; let entropy = &*self.entropy_source; let secp_ctx = &self.secp_ctx; - let path = self.create_one_hop_blinded_path(); - OfferBuilder::deriving_signing_pubkey(description, node_id, expanded_key, entropy, secp_ctx) + let path = self.create_blinded_path().map_err(|_| Bolt12SemanticError::MissingPaths)?; + let builder = OfferBuilder::deriving_signing_pubkey( + description, node_id, expanded_key, entropy, secp_ctx + ) .chain_hash(self.chain_hash) - .path(path) + .path(path); + + Ok(builder) } /// Creates a [`RefundBuilder`] such that the [`Refund`] it builds is recognized by the @@ -7533,10 +7544,13 @@ where /// /// # Privacy /// - /// Uses a one-hop [`BlindedPath`] for the refund with [`ChannelManager::get_our_node_id`] as - /// the introduction node and a derived payer id for payer privacy. As such, currently, the - /// node must be announced. Otherwise, there is no way to find a path to the introduction node - /// in order to send the [`Bolt12Invoice`]. + /// Uses [`MessageRouter::create_blinded_paths`] to construct a [`BlindedPath`] for the refund. + /// However, if one is not found, uses a one-hop [`BlindedPath`] with + /// [`ChannelManager::get_our_node_id`] as the introduction node instead. In the latter case, + /// the node must be announced, otherwise, there is no way to find a path to the introduction in + /// order to send the [`Bolt12Invoice`]. + /// + /// Also, uses a derived payer id in the refund for payer privacy. /// /// # Limitations /// @@ -7545,8 +7559,10 @@ where /// /// # Errors /// - /// Errors if a duplicate `payment_id` is provided given the caveats in the aforementioned link - /// or if `amount_msats` is invalid. + /// Errors if: + /// - a duplicate `payment_id` is provided given the caveats in the aforementioned link, + /// - `amount_msats` is invalid, or + /// - the parameterized [`Router`] is unable to create a blinded path for the refund. /// /// This is not exported to bindings users as builder patterns don't map outside of move semantics. /// @@ -7561,8 +7577,8 @@ where let expanded_key = &self.inbound_payment_key; let entropy = &*self.entropy_source; let secp_ctx = &self.secp_ctx; - let path = self.create_one_hop_blinded_path(); + let path = self.create_blinded_path().map_err(|_| Bolt12SemanticError::MissingPaths)?; let builder = RefundBuilder::deriving_payer_id( description, node_id, expanded_key, entropy, secp_ctx, amount_msats, payment_id )? @@ -7620,8 +7636,11 @@ where /// /// # Errors /// - /// Errors if a duplicate `payment_id` is provided given the caveats in the aforementioned link - /// or if the provided parameters are invalid for the offer. + /// Errors if: + /// - a duplicate `payment_id` is provided given the caveats in the aforementioned link, + /// - the provided parameters are invalid for the offer, + /// - the parameterized [`Router`] is unable to create a blinded reply path for the invoice + /// request. /// /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest /// [`InvoiceRequest::quantity`]: crate::offers::invoice_request::InvoiceRequest::quantity @@ -7654,9 +7673,8 @@ where None => builder, Some(payer_note) => builder.payer_note(payer_note), }; - let invoice_request = builder.build_and_sign()?; - let reply_path = self.create_one_hop_blinded_path(); + let reply_path = self.create_blinded_path().map_err(|_| Bolt12SemanticError::MissingPaths)?; let expiration = StaleExpiration::TimerTicks(1); self.pending_outbound_payments @@ -7732,7 +7750,8 @@ where payment_paths, payment_hash, created_at, expanded_key, entropy )?; let invoice = builder.allow_mpp().build_and_sign(secp_ctx)?; - let reply_path = self.create_one_hop_blinded_path(); + let reply_path = self.create_blinded_path() + .map_err(|_| Bolt12SemanticError::MissingPaths)?; let mut pending_offers_messages = self.pending_offers_messages.lock().unwrap(); if refund.paths().is_empty() { @@ -7859,12 +7878,23 @@ where inbound_payment::get_payment_preimage(payment_hash, payment_secret, &self.inbound_payment_key) } - /// Creates a one-hop blinded path with [`ChannelManager::get_our_node_id`] as the introduction - /// node. - fn create_one_hop_blinded_path(&self) -> BlindedPath { + /// Creates a blinded path by delegating to [`MessageRouter::create_blinded_paths`]. + /// + /// Errors if the `MessageRouter` errors or returns an empty `Vec`. + fn create_blinded_path(&self) -> Result { + let recipient = self.get_our_node_id(); let entropy_source = self.entropy_source.deref(); let secp_ctx = &self.secp_ctx; - BlindedPath::one_hop_for_message(self.get_our_node_id(), entropy_source, secp_ctx).unwrap() + + let peers = self.per_peer_state.read().unwrap() + .iter() + .filter(|(_, peer)| peer.lock().unwrap().latest_features.supports_onion_messages()) + .map(|(node_id, _)| *node_id) + .collect::>(); + + self.router + .create_blinded_paths(recipient, peers, entropy_source, secp_ctx) + .and_then(|paths| paths.into_iter().next().ok_or(())) } /// Creates a one-hop blinded payment path with [`ChannelManager::get_our_node_id`] as the -- 2.39.5