Include invreq in payment onion when retrying async payments

While in the last commit we began including invoice requests in async payment
onions on initial send, further work is needed to include them on retry. Here
we begin storing invreqs in our retry data, and pass them along for inclusion
in the onion on payment retry.

Per BOLTs PR 1149, when paying a static invoice we need to include our original
invoice request in the HTLC onion since the recipient wouldn't have received it
previously.

diff --git a/lightning/src/ln/outbound_payment.rs b/lightning/src/ln/outbound_payment.rs
index b5c167236c6d6a9217205ce0b10132b9004ae4bc..e7d32f9f8e1c3cef6315b5ded0d681dc17aef96c 100644 (file)
--- a/lightning/src/ln/outbound_payment.rs
+++ b/lightning/src/ln/outbound_payment.rs
@@ -94,6 +94,7 @@ pub(crate) enum PendingOutboundPayment {
                payment_secret: Option<PaymentSecret>,
                payment_metadata: Option<Vec<u8>>,
                keysend_preimage: Option<PaymentPreimage>,
+               invoice_request: Option<InvoiceRequest>,
                custom_tlvs: Vec<(u64, Vec<u8>)>,
                pending_amt_msat: u64,
                /// Used to track the fee paid. Present iff the payment was serialized on 0.0.103+.
@@ -948,20 +949,33 @@ impl OutboundPayments {
                };
 
                let payment_params = Some(route_params.payment_params.clone());
-               let (retryable_payment, onion_session_privs) = Self::create_pending_payment(
-                       payment_hash, recipient_onion.clone(), keysend_preimage, &route, Some(retry_strategy),
-                       payment_params, entropy_source, best_block_height
-               );
-               match self.pending_outbound_payments.lock().unwrap().entry(payment_id) {
+               let mut outbounds = self.pending_outbound_payments.lock().unwrap();
+               let onion_session_privs = match outbounds.entry(payment_id) {
                        hash_map::Entry::Occupied(entry) => match entry.get() {
-                               PendingOutboundPayment::InvoiceReceived { .. }
-                               | PendingOutboundPayment::StaticInvoiceReceived { .. } => {
+                               PendingOutboundPayment::InvoiceReceived { .. } => {
+                                       let (retryable_payment, onion_session_privs) = Self::create_pending_payment(
+                                               payment_hash, recipient_onion.clone(), keysend_preimage, None, &route,
+                                               Some(retry_strategy), payment_params, entropy_source, best_block_height
+                                       );
                                        *entry.into_mut() = retryable_payment;
+                                       onion_session_privs
+                               },
+                               PendingOutboundPayment::StaticInvoiceReceived { .. } => {
+                                       let invreq = if let PendingOutboundPayment::StaticInvoiceReceived { invoice_request, .. } = entry.remove() {
+                                               invoice_request
+                                       } else { unreachable!() };
+                                       let (retryable_payment, onion_session_privs) = Self::create_pending_payment(
+                                               payment_hash, recipient_onion.clone(), keysend_preimage, Some(invreq), &route,
+                                               Some(retry_strategy), payment_params, entropy_source, best_block_height
+                                       );
+                                       outbounds.insert(payment_id, retryable_payment);
+                                       onion_session_privs
                                },
                                _ => return Err(Bolt12PaymentError::DuplicateInvoice),
                        },
                        hash_map::Entry::Vacant(_) => return Err(Bolt12PaymentError::UnexpectedInvoice),
-               }
+               };
+               core::mem::drop(outbounds);
 
                let result = self.pay_route_internal(
                        &route, payment_hash, &recipient_onion, keysend_preimage, invoice_request, payment_id,
@@ -1324,14 +1338,14 @@ impl OutboundPayments {
                                }
                        }
                }
-               let (total_msat, recipient_onion, keysend_preimage, onion_session_privs) = {
+               let (total_msat, recipient_onion, keysend_preimage, onion_session_privs, invoice_request) = {
                        let mut outbounds = self.pending_outbound_payments.lock().unwrap();
                        match outbounds.entry(payment_id) {
                                hash_map::Entry::Occupied(mut payment) => {
                                        match payment.get() {
                                                PendingOutboundPayment::Retryable {
                                                        total_msat, keysend_preimage, payment_secret, payment_metadata,
-                                                       custom_tlvs, pending_amt_msat, ..
+                                                       custom_tlvs, pending_amt_msat, invoice_request, ..
                                                } => {
                                                        const RETRY_OVERFLOW_PERCENTAGE: u64 = 10;
                                                        let retry_amt_msat = route.get_total_amount();
@@ -1354,6 +1368,7 @@ impl OutboundPayments {
                                                                custom_tlvs: custom_tlvs.clone(),
                                                        };
                                                        let keysend_preimage = *keysend_preimage;
+                                                       let invoice_request = invoice_request.clone();
 
                                                        let mut onion_session_privs = Vec::with_capacity(route.paths.len());
                                                        for _ in 0..route.paths.len() {
@@ -1366,7 +1381,7 @@ impl OutboundPayments {
 
                                                        payment.get_mut().increment_attempts();
 
-                                                       (total_msat, recipient_onion, keysend_preimage, onion_session_privs)
+                                                       (total_msat, recipient_onion, keysend_preimage, onion_session_privs, invoice_request)
                                                },
                                                PendingOutboundPayment::Legacy { .. } => {
                                                        log_error!(logger, "Unable to retry payments that were initially sent on LDK versions prior to 0.0.102");
@@ -1404,8 +1419,8 @@ impl OutboundPayments {
                        }
                };
                let res = self.pay_route_internal(&route, payment_hash, &recipient_onion, keysend_preimage,
-                       None, payment_id, Some(total_msat), onion_session_privs, node_signer, best_block_height,
-                       &send_payment_along_path);
+                       invoice_request.as_ref(), payment_id, Some(total_msat), onion_session_privs, node_signer,
+                       best_block_height, &send_payment_along_path);
                log_info!(logger, "Result retrying payment id {}: {:?}", &payment_id, res);
                if let Err(e) = res {
                        self.handle_pay_route_err(e, payment_id, payment_hash, route, route_params, router, first_hops, inflight_htlcs, entropy_source, node_signer, best_block_height, logger, pending_events, send_payment_along_path);
@@ -1557,7 +1572,7 @@ impl OutboundPayments {
                        hash_map::Entry::Occupied(_) => Err(PaymentSendFailure::DuplicatePayment),
                        hash_map::Entry::Vacant(entry) => {
                                let (payment, onion_session_privs) = Self::create_pending_payment(
-                                       payment_hash, recipient_onion, keysend_preimage, route, retry_strategy,
+                                       payment_hash, recipient_onion, keysend_preimage, None, route, retry_strategy,
                                        payment_params, entropy_source, best_block_height
                                );
                                entry.insert(payment);
@@ -1568,8 +1583,9 @@ impl OutboundPayments {
 
        fn create_pending_payment<ES: Deref>(
                payment_hash: PaymentHash, recipient_onion: RecipientOnionFields,
-               keysend_preimage: Option<PaymentPreimage>, route: &Route, retry_strategy: Option<Retry>,
-               payment_params: Option<PaymentParameters>, entropy_source: &ES, best_block_height: u32
+               keysend_preimage: Option<PaymentPreimage>, invoice_request: Option<InvoiceRequest>,
+               route: &Route, retry_strategy: Option<Retry>, payment_params: Option<PaymentParameters>,
+               entropy_source: &ES, best_block_height: u32
        ) -> (PendingOutboundPayment, Vec<[u8; 32]>)
        where
                ES::Target: EntropySource,
@@ -1590,6 +1606,7 @@ impl OutboundPayments {
                        payment_secret: recipient_onion.payment_secret,
                        payment_metadata: recipient_onion.payment_metadata,
                        keysend_preimage,
+                       invoice_request,
                        custom_tlvs: recipient_onion.custom_tlvs,
                        starting_block_height: best_block_height,
                        total_msat: route.get_total_amount(),
@@ -2151,6 +2168,7 @@ impl OutboundPayments {
                                        payment_secret: None, // only used for retries, and we'll never retry on startup
                                        payment_metadata: None, // only used for retries, and we'll never retry on startup
                                        keysend_preimage: None, // only used for retries, and we'll never retry on startup
+                                       invoice_request: None, // only used for retries, and we'll never retry on startup
                                        custom_tlvs: Vec::new(), // only used for retries, and we'll never retry on startup
                                        pending_amt_msat: path_amt,
                                        pending_fee_msat: Some(path_fee),
@@ -2237,6 +2255,7 @@ impl_writeable_tlv_based_enum_upgradable!(PendingOutboundPayment,
                (9, custom_tlvs, optional_vec),
                (10, starting_block_height, required),
                (11, remaining_max_total_routing_fee_msat, option),
+               (13, invoice_request, option),
                (not_written, retry_strategy, (static_value, None)),
                (not_written, attempts, (static_value, PaymentAttempts::new())),
        },