Make `FinalOnionHopData` public
[rust-lightning] / lightning / src / ln / channelmanager.rs
index 9536a9366e18506fa586d96c325b7d725e677de2..560a7e58edafb2f8a703dbbc91688c2dac79f993 100644 (file)
@@ -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<DerivedMetadata, secp256k1::All> {
+       ) -> Result<OfferBuilder<DerivedMetadata, secp256k1::All>, 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
        ///
@@ -7545,14 +7559,17 @@ 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.
        ///
        /// [`Refund`]: crate::offers::refund::Refund
        /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
        /// [`Bolt12Invoice::payment_paths`]: crate::offers::invoice::Bolt12Invoice::payment_paths
+       /// [Avoiding Duplicate Payments]: #avoiding-duplicate-payments
        pub fn create_refund_builder(
                &self, description: String, amount_msats: u64, absolute_expiry: Duration,
                payment_id: PaymentId, retry_strategy: Retry, max_total_routing_fee_msat: Option<u64>
@@ -7561,8 +7578,8 @@ 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 +7637,11 @@ 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 +7674,8 @@ 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
@@ -7705,6 +7724,11 @@ where
        /// node meeting the aforementioned criteria, but there's no guarantee that they will be
        /// received and no retries will be made.
        ///
+       /// # Errors
+       ///
+       /// Errors if the parameterized [`Router`] is unable to create a blinded payment path or reply
+       /// path for the invoice.
+       ///
        /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
        pub fn request_refund_payment(&self, refund: &Refund) -> Result<(), Bolt12SemanticError> {
                let expanded_key = &self.inbound_payment_key;
@@ -7716,9 +7740,9 @@ where
 
                match self.create_inbound_payment(Some(amount_msats), relative_expiry, None) {
                        Ok((payment_hash, payment_secret)) => {
-                               let payment_paths = vec![
-                                       self.create_one_hop_blinded_payment_path(payment_secret),
-                               ];
+                               let payment_paths = self.create_blinded_payment_paths(amount_msats, payment_secret)
+                                       .map_err(|_| Bolt12SemanticError::MissingPaths)?;
+
                                #[cfg(not(feature = "no-std"))]
                                let builder = refund.respond_using_derived_keys(
                                        payment_paths, payment_hash, expanded_key, entropy
@@ -7732,7 +7756,8 @@ 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() {
@@ -7859,24 +7884,37 @@ 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<BlindedPath, ()> {
+               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::<Vec<_>>();
+
+               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 path with [`ChannelManager::get_our_node_id`] as the introduction
-       /// node.
-       fn create_one_hop_blinded_payment_path(
-               &self, payment_secret: PaymentSecret
-       ) -> (BlindedPayInfo, BlindedPath) {
+       /// Creates multi-hop blinded payment paths for the given `amount_msats` by delegating to
+       /// [`Router::create_blinded_payment_paths`].
+       fn create_blinded_payment_paths(
+               &self, amount_msats: u64, payment_secret: PaymentSecret
+       ) -> Result<Vec<(BlindedPayInfo, BlindedPath)>, ()> {
                let entropy_source = self.entropy_source.deref();
                let secp_ctx = &self.secp_ctx;
 
+               let first_hops = self.list_usable_channels();
                let payee_node_id = self.get_our_node_id();
-               let max_cltv_expiry = self.best_block.read().unwrap().height() + LATENCY_GRACE_PERIOD_BLOCKS;
+               let max_cltv_expiry = self.best_block.read().unwrap().height() + CLTV_FAR_FAR_AWAY
+                       + LATENCY_GRACE_PERIOD_BLOCKS;
                let payee_tlvs = ReceiveTlvs {
                        payment_secret,
                        payment_constraints: PaymentConstraints {
@@ -7884,10 +7922,9 @@ where
                                htlc_minimum_msat: 1,
                        },
                };
-               // TODO: Err for overflow?
-               BlindedPath::one_hop_for_payment(
-                       payee_node_id, payee_tlvs, entropy_source, secp_ctx
-               ).unwrap()
+               self.router.create_blinded_payment_paths(
+                       payee_node_id, first_hops, payee_tlvs, amount_msats, entropy_source, secp_ctx
+               )
        }
 
        /// Gets a fake short channel id for use in receiving [phantom node payments]. These fake scids
@@ -9127,7 +9164,7 @@ where
                                let amount_msats = match InvoiceBuilder::<DerivedSigningPubkey>::amount_msats(
                                        &invoice_request
                                ) {
-                                       Ok(amount_msats) => Some(amount_msats),
+                                       Ok(amount_msats) => amount_msats,
                                        Err(error) => return Some(OffersMessage::InvoiceError(error.into())),
                                };
                                let invoice_request = match invoice_request.verify(expanded_key, secp_ctx) {
@@ -9137,64 +9174,69 @@ where
                                                return Some(OffersMessage::InvoiceError(error.into()));
                                        },
                                };
-                               let relative_expiry = DEFAULT_RELATIVE_EXPIRY.as_secs() as u32;
 
-                               match self.create_inbound_payment(amount_msats, relative_expiry, None) {
-                                       Ok((payment_hash, payment_secret)) if invoice_request.keys.is_some() => {
-                                               let payment_paths = vec![
-                                                       self.create_one_hop_blinded_payment_path(payment_secret),
-                                               ];
-                                               #[cfg(not(feature = "no-std"))]
-                                               let builder = invoice_request.respond_using_derived_keys(
-                                                       payment_paths, payment_hash
-                                               );
-                                               #[cfg(feature = "no-std")]
-                                               let created_at = Duration::from_secs(
-                                                       self.highest_seen_timestamp.load(Ordering::Acquire) as u64
-                                               );
-                                               #[cfg(feature = "no-std")]
-                                               let builder = invoice_request.respond_using_derived_keys_no_std(
-                                                       payment_paths, payment_hash, created_at
-                                               );
-                                               match builder.and_then(|b| b.allow_mpp().build_and_sign(secp_ctx)) {
-                                                       Ok(invoice) => Some(OffersMessage::Invoice(invoice)),
-                                                       Err(error) => Some(OffersMessage::InvoiceError(error.into())),
-                                               }
-                                       },
-                                       Ok((payment_hash, payment_secret)) => {
-                                               let payment_paths = vec![
-                                                       self.create_one_hop_blinded_payment_path(payment_secret),
-                                               ];
-                                               #[cfg(not(feature = "no-std"))]
-                                               let builder = invoice_request.respond_with(payment_paths, payment_hash);
-                                               #[cfg(feature = "no-std")]
-                                               let created_at = Duration::from_secs(
-                                                       self.highest_seen_timestamp.load(Ordering::Acquire) as u64
-                                               );
-                                               #[cfg(feature = "no-std")]
-                                               let builder = invoice_request.respond_with_no_std(
-                                                       payment_paths, payment_hash, created_at
-                                               );
-                                               let response = builder.and_then(|builder| builder.allow_mpp().build())
-                                                       .map_err(|e| OffersMessage::InvoiceError(e.into()))
-                                                       .and_then(|invoice|
-                                                               match invoice.sign(|invoice| self.node_signer.sign_bolt12_invoice(invoice)) {
-                                                                       Ok(invoice) => Ok(OffersMessage::Invoice(invoice)),
-                                                                       Err(SignError::Signing(())) => Err(OffersMessage::InvoiceError(
-                                                                                       InvoiceError::from_string("Failed signing invoice".to_string())
-                                                                       )),
-                                                                       Err(SignError::Verification(_)) => Err(OffersMessage::InvoiceError(
-                                                                                       InvoiceError::from_string("Failed invoice signature verification".to_string())
-                                                                       )),
-                                                               });
-                                               match response {
-                                                       Ok(invoice) => Some(invoice),
-                                                       Err(error) => Some(error),
-                                               }
+                               let relative_expiry = DEFAULT_RELATIVE_EXPIRY.as_secs() as u32;
+                               let (payment_hash, payment_secret) = match self.create_inbound_payment(
+                                       Some(amount_msats), relative_expiry, None
+                               ) {
+                                       Ok((payment_hash, payment_secret)) => (payment_hash, payment_secret),
+                                       Err(()) => {
+                                               let error = Bolt12SemanticError::InvalidAmount;
+                                               return Some(OffersMessage::InvoiceError(error.into()));
                                        },
+                               };
+
+                               let payment_paths = match self.create_blinded_payment_paths(
+                                       amount_msats, payment_secret
+                               ) {
+                                       Ok(payment_paths) => payment_paths,
                                        Err(()) => {
-                                               Some(OffersMessage::InvoiceError(Bolt12SemanticError::InvalidAmount.into()))
+                                               let error = Bolt12SemanticError::MissingPaths;
+                                               return Some(OffersMessage::InvoiceError(error.into()));
                                        },
+                               };
+
+                               #[cfg(feature = "no-std")]
+                               let created_at = Duration::from_secs(
+                                       self.highest_seen_timestamp.load(Ordering::Acquire) as u64
+                               );
+
+                               if invoice_request.keys.is_some() {
+                                       #[cfg(not(feature = "no-std"))]
+                                       let builder = invoice_request.respond_using_derived_keys(
+                                               payment_paths, payment_hash
+                                       );
+                                       #[cfg(feature = "no-std")]
+                                       let builder = invoice_request.respond_using_derived_keys_no_std(
+                                               payment_paths, payment_hash, created_at
+                                       );
+                                       match builder.and_then(|b| b.allow_mpp().build_and_sign(secp_ctx)) {
+                                               Ok(invoice) => Some(OffersMessage::Invoice(invoice)),
+                                               Err(error) => Some(OffersMessage::InvoiceError(error.into())),
+                                       }
+                               } else {
+                                       #[cfg(not(feature = "no-std"))]
+                                       let builder = invoice_request.respond_with(payment_paths, payment_hash);
+                                       #[cfg(feature = "no-std")]
+                                       let builder = invoice_request.respond_with_no_std(
+                                               payment_paths, payment_hash, created_at
+                                       );
+                                       let response = builder.and_then(|builder| builder.allow_mpp().build())
+                                               .map_err(|e| OffersMessage::InvoiceError(e.into()))
+                                               .and_then(|invoice|
+                                                       match invoice.sign(|invoice| self.node_signer.sign_bolt12_invoice(invoice)) {
+                                                               Ok(invoice) => Ok(OffersMessage::Invoice(invoice)),
+                                                               Err(SignError::Signing(())) => Err(OffersMessage::InvoiceError(
+                                                                               InvoiceError::from_string("Failed signing invoice".to_string())
+                                                               )),
+                                                               Err(SignError::Verification(_)) => Err(OffersMessage::InvoiceError(
+                                                                               InvoiceError::from_string("Failed invoice signature verification".to_string())
+                                                               )),
+                                                       });
+                                       match response {
+                                               Ok(invoice) => Some(invoice),
+                                               Err(error) => Some(error),
+                                       }
                                }
                        },
                        OffersMessage::Invoice(invoice) => {