Merge pull request #2534 from tnull/2023-08-upstream-preflight-probing
[rust-lightning] / lightning / src / ln / outbound_payment.rs
index 50dcdd546083a326e6f4b14340e0d815a621af88..023412e1afb56cdcdd0a2d9195064e5744ccab6c 100644 (file)
@@ -16,8 +16,9 @@ use bitcoin::secp256k1::{self, Secp256k1, SecretKey};
 use crate::sign::{EntropySource, NodeSigner, Recipient};
 use crate::events::{self, PaymentFailureReason};
 use crate::ln::{PaymentHash, PaymentPreimage, PaymentSecret};
-use crate::ln::channelmanager::{ChannelDetails, EventCompletionAction, HTLCSource, IDEMPOTENCY_TIMEOUT_TICKS, PaymentId};
-use crate::ln::onion_utils::HTLCFailReason;
+use crate::ln::channelmanager::{ChannelDetails, EventCompletionAction, HTLCSource, PaymentId};
+use crate::ln::onion_utils::{DecodedOnionFailure, HTLCFailReason};
+use crate::offers::invoice::Bolt12Invoice;
 use crate::routing::router::{InFlightHtlcs, Path, PaymentParameters, Route, RouteParameters, Router};
 use crate::util::errors::APIError;
 use crate::util::logger::Logger;
@@ -32,12 +33,32 @@ use core::ops::Deref;
 use crate::prelude::*;
 use crate::sync::Mutex;
 
+/// The number of ticks of [`ChannelManager::timer_tick_occurred`] until we time-out the idempotency
+/// of payments by [`PaymentId`]. See [`OutboundPayments::remove_stale_payments`].
+///
+/// [`ChannelManager::timer_tick_occurred`]: crate::ln::channelmanager::ChannelManager::timer_tick_occurred
+pub(crate) const IDEMPOTENCY_TIMEOUT_TICKS: u8 = 7;
+
+/// The number of ticks of [`ChannelManager::timer_tick_occurred`] until an invoice request without
+/// a response is timed out.
+///
+/// [`ChannelManager::timer_tick_occurred`]: crate::ln::channelmanager::ChannelManager::timer_tick_occurred
+const INVOICE_REQUEST_TIMEOUT_TICKS: u8 = 3;
+
 /// Stores the session_priv for each part of a payment that is still pending. For versions 0.0.102
 /// and later, also stores information for retrying the payment.
 pub(crate) enum PendingOutboundPayment {
        Legacy {
                session_privs: HashSet<[u8; 32]>,
        },
+       AwaitingInvoice {
+               timer_ticks_without_response: u8,
+               retry_strategy: Retry,
+       },
+       InvoiceReceived {
+               payment_hash: PaymentHash,
+               retry_strategy: Retry,
+       },
        Retryable {
                retry_strategy: Option<Retry>,
                attempts: PaymentAttempts,
@@ -47,6 +68,7 @@ pub(crate) enum PendingOutboundPayment {
                payment_secret: Option<PaymentSecret>,
                payment_metadata: Option<Vec<u8>>,
                keysend_preimage: Option<PaymentPreimage>,
+               custom_tlvs: Vec<(u64, Vec<u8>)>,
                pending_amt_msat: u64,
                /// Used to track the fee paid. Only present if the payment was serialized on 0.0.103+.
                pending_fee_msat: Option<u64>,
@@ -107,6 +129,12 @@ impl PendingOutboundPayment {
                        params.previously_failed_channels.push(scid);
                }
        }
+       fn is_awaiting_invoice(&self) -> bool {
+               match self {
+                       PendingOutboundPayment::AwaitingInvoice { .. } => true,
+                       _ => false,
+               }
+       }
        pub(super) fn is_fulfilled(&self) -> bool {
                match self {
                        PendingOutboundPayment::Fulfilled { .. } => true,
@@ -129,6 +157,8 @@ impl PendingOutboundPayment {
        fn payment_hash(&self) -> Option<PaymentHash> {
                match self {
                        PendingOutboundPayment::Legacy { .. } => None,
+                       PendingOutboundPayment::AwaitingInvoice { .. } => None,
+                       PendingOutboundPayment::InvoiceReceived { payment_hash, .. } => Some(*payment_hash),
                        PendingOutboundPayment::Retryable { payment_hash, .. } => Some(*payment_hash),
                        PendingOutboundPayment::Fulfilled { payment_hash, .. } => *payment_hash,
                        PendingOutboundPayment::Abandoned { payment_hash, .. } => Some(*payment_hash),
@@ -141,8 +171,9 @@ impl PendingOutboundPayment {
                        PendingOutboundPayment::Legacy { session_privs } |
                                PendingOutboundPayment::Retryable { session_privs, .. } |
                                PendingOutboundPayment::Fulfilled { session_privs, .. } |
-                               PendingOutboundPayment::Abandoned { session_privs, .. }
-                       => session_privs,
+                               PendingOutboundPayment::Abandoned { session_privs, .. } => session_privs,
+                       PendingOutboundPayment::AwaitingInvoice { .. } |
+                               PendingOutboundPayment::InvoiceReceived { .. } => { debug_assert!(false); return; },
                });
                let payment_hash = self.payment_hash();
                *self = PendingOutboundPayment::Fulfilled { session_privs, payment_hash, timer_ticks_without_htlcs: 0 };
@@ -157,6 +188,12 @@ impl PendingOutboundPayment {
                                payment_hash: *payment_hash,
                                reason: Some(reason)
                        };
+               } else if let PendingOutboundPayment::InvoiceReceived { payment_hash, .. } = self {
+                       *self = PendingOutboundPayment::Abandoned {
+                               session_privs: HashSet::new(),
+                               payment_hash: *payment_hash,
+                               reason: Some(reason)
+                       };
                }
        }
 
@@ -168,7 +205,9 @@ impl PendingOutboundPayment {
                                PendingOutboundPayment::Fulfilled { session_privs, .. } |
                                PendingOutboundPayment::Abandoned { session_privs, .. } => {
                                        session_privs.remove(session_priv)
-                               }
+                               },
+                       PendingOutboundPayment::AwaitingInvoice { .. } |
+                               PendingOutboundPayment::InvoiceReceived { .. } => { debug_assert!(false); false },
                };
                if remove_res {
                        if let PendingOutboundPayment::Retryable { ref mut pending_amt_msat, ref mut pending_fee_msat, .. } = self {
@@ -187,7 +226,9 @@ impl PendingOutboundPayment {
                        PendingOutboundPayment::Legacy { session_privs } |
                                PendingOutboundPayment::Retryable { session_privs, .. } => {
                                        session_privs.insert(session_priv)
-                               }
+                               },
+                       PendingOutboundPayment::AwaitingInvoice { .. } |
+                               PendingOutboundPayment::InvoiceReceived { .. } => { debug_assert!(false); false },
                        PendingOutboundPayment::Fulfilled { .. } => false,
                        PendingOutboundPayment::Abandoned { .. } => false,
                };
@@ -209,7 +250,9 @@ impl PendingOutboundPayment {
                                PendingOutboundPayment::Fulfilled { session_privs, .. } |
                                PendingOutboundPayment::Abandoned { session_privs, .. } => {
                                        session_privs.len()
-                               }
+                               },
+                       PendingOutboundPayment::AwaitingInvoice { .. } => 0,
+                       PendingOutboundPayment::InvoiceReceived { .. } => 0,
                }
        }
 }
@@ -222,7 +265,7 @@ pub enum Retry {
        /// Each attempt may be multiple HTLCs along multiple paths if the router decides to split up a
        /// retry, and may retry multiple failed HTLCs at once if they failed around the same time and
        /// were retried along a route from a single call to [`Router::find_route_with_id`].
-       Attempts(usize),
+       Attempts(u32),
        #[cfg(not(feature = "no-std"))]
        /// Time elapsed before abandoning retries for a payment. At least one attempt at payment is made;
        /// see [`PaymentParameters::expiry_time`] to avoid any attempt at payment after a specific time.
@@ -231,6 +274,19 @@ pub enum Retry {
        Timeout(core::time::Duration),
 }
 
+#[cfg(feature = "no-std")]
+impl_writeable_tlv_based_enum!(Retry,
+       ;
+       (0, Attempts)
+);
+
+#[cfg(not(feature = "no-std"))]
+impl_writeable_tlv_based_enum!(Retry,
+       ;
+       (0, Attempts),
+       (2, Timeout)
+);
+
 impl Retry {
        pub(crate) fn is_retryable_now(&self, attempts: &PaymentAttempts) -> bool {
                match (self, attempts) {
@@ -264,7 +320,7 @@ pub(crate) type PaymentAttempts = PaymentAttemptsUsingTime<ConfiguredTime>;
 pub(crate) struct PaymentAttemptsUsingTime<T: Time> {
        /// This count will be incremented only after the result of the attempt is known. When it's 0,
        /// it means the result of the first attempt is not known yet.
-       pub(crate) count: usize,
+       pub(crate) count: u32,
        /// This field is only used when retry is `Retry::Timeout` which is only build with feature std
        #[cfg(not(feature = "no-std"))]
        first_attempted_at: T,
@@ -335,7 +391,7 @@ pub enum RetryableSendFailure {
 /// is in, see the description of individual enum states for more.
 ///
 /// [`ChannelManager::send_payment_with_route`]: crate::ln::channelmanager::ChannelManager::send_payment_with_route
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, PartialEq, Eq)]
 pub enum PaymentSendFailure {
        /// A parameter which was passed to send_payment was invalid, preventing us from attempting to
        /// send the payment at all.
@@ -400,6 +456,27 @@ pub enum PaymentSendFailure {
        },
 }
 
+/// An error when attempting to pay a BOLT 12 invoice.
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub(super) enum Bolt12PaymentError {
+       /// The invoice was not requested.
+       UnexpectedInvoice,
+       /// Payment for an invoice with the corresponding [`PaymentId`] was already initiated.
+       DuplicateInvoice,
+}
+
+/// Indicates that we failed to send a payment probe. Further errors may be surfaced later via
+/// [`Event::ProbeFailed`].
+///
+/// [`Event::ProbeFailed`]: crate::events::Event::ProbeFailed
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub enum ProbeSendFailure {
+       /// We were unable to find a route to the destination.
+       RouteNotFound,
+       /// We failed to send the payment probes.
+       SendingFailed(PaymentSendFailure),
+}
+
 /// Information which is provided, encrypted, to the payment recipient when sending HTLCs.
 ///
 /// This should generally be constructed with data communicated to us from the recipient (via a
@@ -431,10 +508,13 @@ pub struct RecipientOnionFields {
        /// [`Self::payment_secret`] and while nearly all lightning senders support secrets, metadata
        /// may not be supported as universally.
        pub payment_metadata: Option<Vec<u8>>,
+       /// See [`Self::custom_tlvs`] for more info.
+       pub(super) custom_tlvs: Vec<(u64, Vec<u8>)>,
 }
 
 impl_writeable_tlv_based!(RecipientOnionFields, {
        (0, payment_secret, option),
+       (1, custom_tlvs, optional_vec),
        (2, payment_metadata, option),
 });
 
@@ -443,7 +523,7 @@ impl RecipientOnionFields {
        /// set of onion fields for today's BOLT11 invoices - most nodes require a [`PaymentSecret`]
        /// but do not require or provide any further data.
        pub fn secret_only(payment_secret: PaymentSecret) -> Self {
-               Self { payment_secret: Some(payment_secret), payment_metadata: None }
+               Self { payment_secret: Some(payment_secret), payment_metadata: None, custom_tlvs: Vec::new() }
        }
 
        /// Creates a new [`RecipientOnionFields`] with no fields. This generally does not create
@@ -455,7 +535,46 @@ impl RecipientOnionFields {
        /// [`ChannelManager::send_spontaneous_payment`]: super::channelmanager::ChannelManager::send_spontaneous_payment
        /// [`RecipientOnionFields::secret_only`]: RecipientOnionFields::secret_only
        pub fn spontaneous_empty() -> Self {
-               Self { payment_secret: None, payment_metadata: None }
+               Self { payment_secret: None, payment_metadata: None, custom_tlvs: Vec::new() }
+       }
+
+       /// Creates a new [`RecipientOnionFields`] from an existing one, adding custom TLVs. Each
+       /// TLV is provided as a `(u64, Vec<u8>)` for the type number and serialized value
+       /// respectively. TLV type numbers must be unique and within the range
+       /// reserved for custom types, i.e. >= 2^16, otherwise this method will return `Err(())`.
+       ///
+       /// This method will also error for types in the experimental range which have been
+       /// standardized within the protocol, which only includes 5482373484 (keysend) for now.
+       ///
+       /// See [`Self::custom_tlvs`] for more info.
+       pub fn with_custom_tlvs(mut self, mut custom_tlvs: Vec<(u64, Vec<u8>)>) -> Result<Self, ()> {
+               custom_tlvs.sort_unstable_by_key(|(typ, _)| *typ);
+               let mut prev_type = None;
+               for (typ, _) in custom_tlvs.iter() {
+                       if *typ < 1 << 16 { return Err(()); }
+                       if *typ == 5482373484 { return Err(()); } // keysend
+                       match prev_type {
+                               Some(prev) if prev >= *typ => return Err(()),
+                               _ => {},
+                       }
+                       prev_type = Some(*typ);
+               }
+               self.custom_tlvs = custom_tlvs;
+               Ok(self)
+       }
+
+       /// Gets the custom TLVs that will be sent or have been received.
+       ///
+       /// Custom TLVs allow sending extra application-specific data with a payment. They provide
+       /// additional flexibility on top of payment metadata, as while other implementations may
+       /// require `payment_metadata` to reflect metadata provided in an invoice, custom TLVs
+       /// do not have this restriction.
+       ///
+       /// Note that if this field is non-empty, it will contain strictly increasing TLVs, each
+       /// represented by a `(u64, Vec<u8>)` for its type number and serialized value respectively.
+       /// This is validated when setting this field using [`Self::with_custom_tlvs`].
+       pub fn custom_tlvs(&self) -> &Vec<(u64, Vec<u8>)> {
+               &self.custom_tlvs
        }
 
        /// When we have received some HTLC(s) towards an MPP payment, as we receive further HTLC(s) we
@@ -468,7 +587,17 @@ impl RecipientOnionFields {
        pub(super) fn check_merge(&mut self, further_htlc_fields: &mut Self) -> Result<(), ()> {
                if self.payment_secret != further_htlc_fields.payment_secret { return Err(()); }
                if self.payment_metadata != further_htlc_fields.payment_metadata { return Err(()); }
-               // For custom TLVs we should just drop non-matching ones, but not reject the payment.
+
+               let tlvs = &mut self.custom_tlvs;
+               let further_tlvs = &mut further_htlc_fields.custom_tlvs;
+
+               let even_tlvs = tlvs.iter().filter(|(typ, _)| *typ % 2 == 0);
+               let further_even_tlvs = further_tlvs.iter().filter(|(typ, _)| *typ % 2 == 0);
+               if even_tlvs.ne(further_even_tlvs) { return Err(()) }
+
+               tlvs.retain(|tlv| further_tlvs.iter().any(|further_tlv| tlv == further_tlv));
+               further_tlvs.retain(|further_tlv| tlvs.iter().any(|tlv| tlv == further_tlv));
+
                Ok(())
        }
 }
@@ -585,6 +714,50 @@ impl OutboundPayments {
                }
        }
 
+       #[allow(unused)]
+       pub(super) fn send_payment_for_bolt12_invoice<R: Deref, ES: Deref, NS: Deref, IH, SP, L: Deref>(
+               &self, invoice: &Bolt12Invoice, payment_id: PaymentId, router: &R,
+               first_hops: Vec<ChannelDetails>, inflight_htlcs: IH, entropy_source: &ES, node_signer: &NS,
+               best_block_height: u32, logger: &L,
+               pending_events: &Mutex<VecDeque<(events::Event, Option<EventCompletionAction>)>>,
+               send_payment_along_path: SP,
+       ) -> Result<(), Bolt12PaymentError>
+       where
+               R::Target: Router,
+               ES::Target: EntropySource,
+               NS::Target: NodeSigner,
+               L::Target: Logger,
+               IH: Fn() -> InFlightHtlcs,
+               SP: Fn(SendAlongPathArgs) -> Result<(), APIError>,
+       {
+               let payment_hash = invoice.payment_hash();
+               match self.pending_outbound_payments.lock().unwrap().entry(payment_id) {
+                       hash_map::Entry::Occupied(entry) => match entry.get() {
+                               PendingOutboundPayment::AwaitingInvoice { retry_strategy, .. } => {
+                                       *entry.into_mut() = PendingOutboundPayment::InvoiceReceived {
+                                               payment_hash,
+                                               retry_strategy: *retry_strategy,
+                                       };
+                               },
+                               _ => return Err(Bolt12PaymentError::DuplicateInvoice),
+                       },
+                       hash_map::Entry::Vacant(_) => return Err(Bolt12PaymentError::UnexpectedInvoice),
+               };
+
+               let route_params = RouteParameters {
+                       payment_params: PaymentParameters::from_bolt12_invoice(&invoice),
+                       final_value_msat: invoice.amount_msats(),
+               };
+
+               self.find_route_and_send_payment(
+                       payment_hash, payment_id, route_params, router, first_hops, &inflight_htlcs,
+                       entropy_source, node_signer, best_block_height, logger, pending_events,
+                       &send_payment_along_path
+               );
+
+               Ok(())
+       }
+
        pub(super) fn check_retry_payments<R: Deref, ES: Deref, NS: Deref, SP, IH, FH, L: Deref>(
                &self, router: &R, first_hops: FH, inflight_htlcs: IH, entropy_source: &ES, node_signer: &NS,
                best_block_height: u32,
@@ -619,14 +792,14 @@ impl OutboundPayments {
                        }
                        core::mem::drop(outbounds);
                        if let Some((payment_hash, payment_id, route_params)) = retry_id_route_params {
-                               self.retry_payment_internal(payment_hash, payment_id, route_params, router, first_hops(), &inflight_htlcs, entropy_source, node_signer, best_block_height, logger, pending_events, &send_payment_along_path)
+                               self.find_route_and_send_payment(payment_hash, payment_id, route_params, router, first_hops(), &inflight_htlcs, entropy_source, node_signer, best_block_height, logger, pending_events, &send_payment_along_path)
                        } else { break }
                }
 
                let mut outbounds = self.pending_outbound_payments.lock().unwrap();
                outbounds.retain(|pmt_id, pmt| {
                        let mut retain = true;
-                       if !pmt.is_auto_retryable_now() && pmt.remaining_parts() == 0 {
+                       if !pmt.is_auto_retryable_now() && pmt.remaining_parts() == 0 && !pmt.is_awaiting_invoice() {
                                pmt.mark_abandoned(PaymentFailureReason::RetriesExhausted);
                                if let PendingOutboundPayment::Abandoned { payment_hash, reason, .. } = pmt {
                                        pending_events.lock().unwrap().push_back((events::Event::PaymentFailed {
@@ -644,7 +817,8 @@ impl OutboundPayments {
        pub(super) fn needs_abandon(&self) -> bool {
                let outbounds = self.pending_outbound_payments.lock().unwrap();
                outbounds.iter().any(|(_, pmt)|
-                       !pmt.is_auto_retryable_now() && pmt.remaining_parts() == 0 && !pmt.is_fulfilled())
+                       !pmt.is_auto_retryable_now() && pmt.remaining_parts() == 0 && !pmt.is_fulfilled() &&
+                       !pmt.is_awaiting_invoice())
        }
 
        /// Errors immediately on [`RetryableSendFailure`] error conditions. Otherwise, further errors may
@@ -669,6 +843,8 @@ impl OutboundPayments {
        {
                #[cfg(feature = "std")] {
                        if has_expired(&route_params) {
+                               log_error!(logger, "Payment with id {} and hash {} had expired before we started paying",
+                                       payment_id, payment_hash);
                                return Err(RetryableSendFailure::PaymentExpired)
                        }
                }
@@ -677,23 +853,32 @@ impl OutboundPayments {
                        &node_signer.get_node_id(Recipient::Node).unwrap(), &route_params,
                        Some(&first_hops.iter().collect::<Vec<_>>()), inflight_htlcs(),
                        payment_hash, payment_id,
-               ).map_err(|_| RetryableSendFailure::RouteNotFound)?;
+               ).map_err(|_| {
+                       log_error!(logger, "Failed to find route for payment with id {} and hash {}",
+                               payment_id, payment_hash);
+                       RetryableSendFailure::RouteNotFound
+               })?;
 
                let onion_session_privs = self.add_new_pending_payment(payment_hash,
                        recipient_onion.clone(), payment_id, keysend_preimage, &route, Some(retry_strategy),
                        Some(route_params.payment_params.clone()), entropy_source, best_block_height)
-                       .map_err(|_| RetryableSendFailure::DuplicatePayment)?;
+                       .map_err(|_| {
+                               log_error!(logger, "Payment with id {} is already pending. New payment had payment hash {}",
+                                       payment_id, payment_hash);
+                               RetryableSendFailure::DuplicatePayment
+                       })?;
 
-               let res = self.pay_route_internal(&route, payment_hash, recipient_onion, None, payment_id, None,
+               let res = self.pay_route_internal(&route, payment_hash, recipient_onion, keysend_preimage, payment_id, None,
                        onion_session_privs, node_signer, best_block_height, &send_payment_along_path);
-               log_info!(logger, "Result sending payment with id {}: {:?}", log_bytes!(payment_id.0), res);
+               log_info!(logger, "Sending payment with id {} and hash {} returned {:?}",
+                       payment_id, payment_hash, 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);
                }
                Ok(())
        }
 
-       fn retry_payment_internal<R: Deref, NS: Deref, ES: Deref, IH, SP, L: Deref>(
+       fn find_route_and_send_payment<R: Deref, NS: Deref, ES: Deref, IH, SP, L: Deref>(
                &self, payment_hash: PaymentHash, payment_id: PaymentId, route_params: RouteParameters,
                router: &R, first_hops: Vec<ChannelDetails>, inflight_htlcs: &IH, entropy_source: &ES,
                node_signer: &NS, best_block_height: u32, logger: &L,
@@ -709,7 +894,7 @@ impl OutboundPayments {
        {
                #[cfg(feature = "std")] {
                        if has_expired(&route_params) {
-                               log_error!(logger, "Payment params expired on retry, abandoning payment {}", log_bytes!(payment_id.0));
+                               log_error!(logger, "Payment params expired on retry, abandoning payment {}", &payment_id);
                                self.abandon_payment(payment_id, PaymentFailureReason::PaymentExpired, pending_events);
                                return
                        }
@@ -722,7 +907,7 @@ impl OutboundPayments {
                ) {
                        Ok(route) => route,
                        Err(e) => {
-                               log_error!(logger, "Failed to find a route on retry, abandoning payment {}: {:#?}", log_bytes!(payment_id.0), e);
+                               log_error!(logger, "Failed to find a route on retry, abandoning payment {}: {:#?}", &payment_id, e);
                                self.abandon_payment(payment_id, PaymentFailureReason::RouteNotFound, pending_events);
                                return
                        }
@@ -735,12 +920,6 @@ impl OutboundPayments {
                        }
                }
 
-               const RETRY_OVERFLOW_PERCENTAGE: u64 = 10;
-               let mut onion_session_privs = Vec::with_capacity(route.paths.len());
-               for _ in 0..route.paths.len() {
-                       onion_session_privs.push(entropy_source.get_secure_random_bytes());
-               }
-
                macro_rules! abandon_with_entry {
                        ($payment: expr, $reason: expr) => {
                                $payment.get_mut().mark_abandoned($reason);
@@ -756,29 +935,74 @@ impl OutboundPayments {
                                }
                        }
                }
-               let (total_msat, recipient_onion, keysend_preimage) = {
+               let (total_msat, recipient_onion, keysend_preimage, onion_session_privs) = {
                        let mut outbounds = self.pending_outbound_payments.lock().unwrap();
                        match outbounds.entry(payment_id) {
                                hash_map::Entry::Occupied(mut payment) => {
-                                       let res = match payment.get() {
+                                       match payment.get() {
                                                PendingOutboundPayment::Retryable {
-                                                       total_msat, keysend_preimage, payment_secret, payment_metadata, pending_amt_msat, ..
+                                                       total_msat, keysend_preimage, payment_secret, payment_metadata,
+                                                       custom_tlvs, pending_amt_msat, ..
                                                } => {
+                                                       const RETRY_OVERFLOW_PERCENTAGE: u64 = 10;
                                                        let retry_amt_msat = route.get_total_amount();
                                                        if retry_amt_msat + *pending_amt_msat > *total_msat * (100 + RETRY_OVERFLOW_PERCENTAGE) / 100 {
                                                                log_error!(logger, "retry_amt_msat of {} will put pending_amt_msat (currently: {}) more than 10% over total_payment_amt_msat of {}", retry_amt_msat, pending_amt_msat, total_msat);
                                                                abandon_with_entry!(payment, PaymentFailureReason::UnexpectedError);
                                                                return
                                                        }
-                                                       (*total_msat, RecipientOnionFields {
-                                                                       payment_secret: *payment_secret,
-                                                                       payment_metadata: payment_metadata.clone(),
-                                                               }, *keysend_preimage)
+
+                                                       if !payment.get().is_retryable_now() {
+                                                               log_error!(logger, "Retries exhausted for payment id {}", &payment_id);
+                                                               abandon_with_entry!(payment, PaymentFailureReason::RetriesExhausted);
+                                                               return
+                                                       }
+
+                                                       let total_msat = *total_msat;
+                                                       let recipient_onion = RecipientOnionFields {
+                                                               payment_secret: *payment_secret,
+                                                               payment_metadata: payment_metadata.clone(),
+                                                               custom_tlvs: custom_tlvs.clone(),
+                                                       };
+                                                       let keysend_preimage = *keysend_preimage;
+
+                                                       let mut onion_session_privs = Vec::with_capacity(route.paths.len());
+                                                       for _ in 0..route.paths.len() {
+                                                               onion_session_privs.push(entropy_source.get_secure_random_bytes());
+                                                       }
+
+                                                       for (path, session_priv_bytes) in route.paths.iter().zip(onion_session_privs.iter()) {
+                                                               assert!(payment.get_mut().insert(*session_priv_bytes, path));
+                                                       }
+
+                                                       payment.get_mut().increment_attempts();
+
+                                                       (total_msat, recipient_onion, keysend_preimage, onion_session_privs)
                                                },
                                                PendingOutboundPayment::Legacy { .. } => {
                                                        log_error!(logger, "Unable to retry payments that were initially sent on LDK versions prior to 0.0.102");
                                                        return
                                                },
+                                               PendingOutboundPayment::AwaitingInvoice { .. } => {
+                                                       log_error!(logger, "Payment not yet sent");
+                                                       return
+                                               },
+                                               PendingOutboundPayment::InvoiceReceived { payment_hash, retry_strategy } => {
+                                                       let total_amount = route_params.final_value_msat;
+                                                       let recipient_onion = RecipientOnionFields {
+                                                               payment_secret: None,
+                                                               payment_metadata: None,
+                                                               custom_tlvs: vec![],
+                                                       };
+                                                       let retry_strategy = Some(*retry_strategy);
+                                                       let payment_params = Some(route_params.payment_params.clone());
+                                                       let (retryable_payment, onion_session_privs) = self.create_pending_payment(
+                                                               *payment_hash, recipient_onion.clone(), None, &route,
+                                                               retry_strategy, payment_params, entropy_source, best_block_height
+                                                       );
+                                                       *payment.into_mut() = retryable_payment;
+                                                       (total_amount, recipient_onion, None, onion_session_privs)
+                                               },
                                                PendingOutboundPayment::Fulfilled { .. } => {
                                                        log_error!(logger, "Payment already completed");
                                                        return
@@ -787,20 +1011,10 @@ impl OutboundPayments {
                                                        log_error!(logger, "Payment already abandoned (with some HTLCs still pending)");
                                                        return
                                                },
-                                       };
-                                       if !payment.get().is_retryable_now() {
-                                               log_error!(logger, "Retries exhausted for payment id {}", log_bytes!(payment_id.0));
-                                               abandon_with_entry!(payment, PaymentFailureReason::RetriesExhausted);
-                                               return
                                        }
-                                       payment.get_mut().increment_attempts();
-                                       for (path, session_priv_bytes) in route.paths.iter().zip(onion_session_privs.iter()) {
-                                               assert!(payment.get_mut().insert(*session_priv_bytes, path));
-                                       }
-                                       res
                                },
                                hash_map::Entry::Vacant(_) => {
-                                       log_error!(logger, "Payment with ID {} not found", log_bytes!(payment_id.0));
+                                       log_error!(logger, "Payment with ID {} not found", &payment_id);
                                        return
                                }
                        }
@@ -808,7 +1022,7 @@ impl OutboundPayments {
                let res = self.pay_route_internal(&route, payment_hash, recipient_onion, keysend_preimage,
                        payment_id, Some(total_msat), onion_session_privs, node_signer, best_block_height,
                        &send_payment_along_path);
-               log_info!(logger, "Result retrying payment id {}: {:?}", log_bytes!(payment_id.0), res);
+               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);
                }
@@ -831,14 +1045,14 @@ impl OutboundPayments {
                match err {
                        PaymentSendFailure::AllFailedResendSafe(errs) => {
                                Self::push_path_failed_evs_and_scids(payment_id, payment_hash, &mut route_params, route.paths, errs.into_iter().map(|e| Err(e)), logger, pending_events);
-                               self.retry_payment_internal(payment_hash, payment_id, route_params, router, first_hops, inflight_htlcs, entropy_source, node_signer, best_block_height, logger, pending_events, send_payment_along_path);
+                               self.find_route_and_send_payment(payment_hash, payment_id, route_params, router, first_hops, inflight_htlcs, entropy_source, node_signer, best_block_height, logger, pending_events, send_payment_along_path);
                        },
                        PaymentSendFailure::PartialFailure { failed_paths_retry: Some(mut retry), results, .. } => {
                                Self::push_path_failed_evs_and_scids(payment_id, payment_hash, &mut retry, route.paths, results.into_iter(), logger, pending_events);
                                // Some paths were sent, even if we failed to send the full MPP value our recipient may
                                // misbehave and claim the funds, at which point we have to consider the payment sent, so
                                // return `Ok()` here, ignoring any retry errors.
-                               self.retry_payment_internal(payment_hash, payment_id, retry, router, first_hops, inflight_htlcs, entropy_source, node_signer, best_block_height, logger, pending_events, send_payment_along_path);
+                               self.find_route_and_send_payment(payment_hash, payment_id, retry, router, first_hops, inflight_htlcs, entropy_source, node_signer, best_block_height, logger, pending_events, send_payment_along_path);
                        },
                        PaymentSendFailure::PartialFailure { failed_paths_retry: None, .. } => {
                                // This may happen if we send a payment and some paths fail, but only due to a temporary
@@ -901,6 +1115,7 @@ impl OutboundPayments {
                F: Fn(SendAlongPathArgs) -> Result<(), APIError>,
        {
                let payment_id = PaymentId(entropy_source.get_secure_random_bytes());
+               let payment_secret = PaymentSecret(entropy_source.get_secure_random_bytes());
 
                let payment_hash = probing_cookie_from_id(&payment_id, probing_cookie_secret);
 
@@ -910,9 +1125,9 @@ impl OutboundPayments {
                        }))
                }
 
-               let route = Route { paths: vec![path], payment_params: None };
+               let route = Route { paths: vec![path], route_params: None };
                let onion_session_privs = self.add_new_pending_payment(payment_hash,
-                       RecipientOnionFields::spontaneous_empty(), payment_id, None, &route, None, None,
+                       RecipientOnionFields::secret_only(payment_secret), payment_id, None, &route, None, None,
                        entropy_source, best_block_height)?;
 
                match self.pay_route_internal(&route, payment_hash, RecipientOnionFields::spontaneous_empty(),
@@ -951,35 +1166,70 @@ impl OutboundPayments {
                keysend_preimage: Option<PaymentPreimage>, route: &Route, retry_strategy: Option<Retry>,
                payment_params: Option<PaymentParameters>, entropy_source: &ES, best_block_height: u32
        ) -> Result<Vec<[u8; 32]>, PaymentSendFailure> where ES::Target: EntropySource {
+               let mut pending_outbounds = self.pending_outbound_payments.lock().unwrap();
+               match pending_outbounds.entry(payment_id) {
+                       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_params, entropy_source, best_block_height
+                               );
+                               entry.insert(payment);
+                               Ok(onion_session_privs)
+                       },
+               }
+       }
+
+       fn create_pending_payment<ES: Deref>(
+               &self, 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
+       ) -> (PendingOutboundPayment, Vec<[u8; 32]>)
+       where
+               ES::Target: EntropySource,
+       {
                let mut onion_session_privs = Vec::with_capacity(route.paths.len());
                for _ in 0..route.paths.len() {
                        onion_session_privs.push(entropy_source.get_secure_random_bytes());
                }
 
+               let mut payment = PendingOutboundPayment::Retryable {
+                       retry_strategy,
+                       attempts: PaymentAttempts::new(),
+                       payment_params,
+                       session_privs: HashSet::new(),
+                       pending_amt_msat: 0,
+                       pending_fee_msat: Some(0),
+                       payment_hash,
+                       payment_secret: recipient_onion.payment_secret,
+                       payment_metadata: recipient_onion.payment_metadata,
+                       keysend_preimage,
+                       custom_tlvs: recipient_onion.custom_tlvs,
+                       starting_block_height: best_block_height,
+                       total_msat: route.get_total_amount(),
+               };
+
+               for (path, session_priv_bytes) in route.paths.iter().zip(onion_session_privs.iter()) {
+                       assert!(payment.insert(*session_priv_bytes, path));
+               }
+
+               (payment, onion_session_privs)
+       }
+
+       #[allow(unused)]
+       pub(super) fn add_new_awaiting_invoice(
+               &self, payment_id: PaymentId, retry_strategy: Retry
+       ) -> Result<(), ()> {
                let mut pending_outbounds = self.pending_outbound_payments.lock().unwrap();
                match pending_outbounds.entry(payment_id) {
-                       hash_map::Entry::Occupied(_) => Err(PaymentSendFailure::DuplicatePayment),
+                       hash_map::Entry::Occupied(_) => Err(()),
                        hash_map::Entry::Vacant(entry) => {
-                               let payment = entry.insert(PendingOutboundPayment::Retryable {
+                               entry.insert(PendingOutboundPayment::AwaitingInvoice {
+                                       timer_ticks_without_response: 0,
                                        retry_strategy,
-                                       attempts: PaymentAttempts::new(),
-                                       payment_params,
-                                       session_privs: HashSet::new(),
-                                       pending_amt_msat: 0,
-                                       pending_fee_msat: Some(0),
-                                       payment_hash,
-                                       payment_secret: recipient_onion.payment_secret,
-                                       payment_metadata: recipient_onion.payment_metadata,
-                                       keysend_preimage,
-                                       starting_block_height: best_block_height,
-                                       total_msat: route.get_total_amount(),
                                });
 
-                               for (path, session_priv_bytes) in route.paths.iter().zip(onion_session_privs.iter()) {
-                                       assert!(payment.insert(*session_priv_bytes, path));
-                               }
-
-                               Ok(onion_session_privs)
+                               Ok(())
                        },
                }
        }
@@ -997,7 +1247,9 @@ impl OutboundPayments {
                if route.paths.len() < 1 {
                        return Err(PaymentSendFailure::ParameterError(APIError::InvalidRoute{err: "There must be at least one path to send over".to_owned()}));
                }
-               if recipient_onion.payment_secret.is_none() && route.paths.len() > 1 {
+               if recipient_onion.payment_secret.is_none() && route.paths.len() > 1
+                       && !route.paths.iter().any(|p| p.blinded_tail.is_some())
+               {
                        return Err(PaymentSendFailure::ParameterError(APIError::APIMisuseError{err: "Payment secret is required for multi-path payments".to_owned()}));
                }
                let mut total_value = 0;
@@ -1008,10 +1260,6 @@ impl OutboundPayments {
                                path_errs.push(Err(APIError::InvalidRoute{err: "Path didn't go anywhere/had bogus size".to_owned()}));
                                continue 'path_check;
                        }
-                       if path.blinded_tail.is_some() {
-                               path_errs.push(Err(APIError::InvalidRoute{err: "Sending to blinded paths isn't supported yet".to_owned()}));
-                               continue 'path_check;
-                       }
                        let dest_hop_idx = if path.blinded_tail.is_some() && path.blinded_tail.as_ref().unwrap().hops.len() > 1 {
                                usize::max_value() } else { path.hops.len() - 1 };
                        for (idx, hop) in path.hops.iter().enumerate() {
@@ -1078,9 +1326,9 @@ impl OutboundPayments {
                                results,
                                payment_id,
                                failed_paths_retry: if pending_amt_unsent != 0 {
-                                       if let Some(payment_params) = &route.payment_params {
+                                       if let Some(payment_params) = route.route_params.as_ref().map(|p| p.payment_params.clone()) {
                                                Some(RouteParameters {
-                                                       payment_params: payment_params.clone(),
+                                                       payment_params: payment_params,
                                                        final_value_msat: pending_amt_unsent,
                                                })
                                        } else { None }
@@ -1121,7 +1369,7 @@ impl OutboundPayments {
 
        pub(super) fn claim_htlc<L: Deref>(
                &self, payment_id: PaymentId, payment_preimage: PaymentPreimage, session_priv: SecretKey,
-               path: Path, from_onchain: bool,
+               path: Path, from_onchain: bool, ev_completion_action: EventCompletionAction,
                pending_events: &Mutex<VecDeque<(events::Event, Option<EventCompletionAction>)>>,
                logger: &L,
        ) where L::Target: Logger {
@@ -1132,13 +1380,14 @@ impl OutboundPayments {
                if let hash_map::Entry::Occupied(mut payment) = outbounds.entry(payment_id) {
                        if !payment.get().is_fulfilled() {
                                let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
+                               log_info!(logger, "Payment with id {} and hash {} sent!", payment_id, payment_hash);
                                let fee_paid_msat = payment.get().get_pending_fee_msat();
                                pending_events.push_back((events::Event::PaymentSent {
                                        payment_id: Some(payment_id),
                                        payment_preimage,
                                        payment_hash,
                                        fee_paid_msat,
-                               }, None));
+                               }, Some(ev_completion_action.clone())));
                                payment.get_mut().mark_fulfilled();
                        }
 
@@ -1155,11 +1404,11 @@ impl OutboundPayments {
                                                payment_id,
                                                payment_hash,
                                                path,
-                                       }, None));
+                                       }, Some(ev_completion_action)));
                                }
                        }
                } else {
-                       log_trace!(logger, "Received duplicative fulfill for HTLC with payment_preimage {}", log_bytes!(payment_preimage.0));
+                       log_trace!(logger, "Received duplicative fulfill for HTLC with payment_preimage {}", &payment_preimage);
                }
        }
 
@@ -1188,19 +1437,19 @@ impl OutboundPayments {
                }
        }
 
-       pub(super) fn remove_stale_resolved_payments(&self,
-               pending_events: &Mutex<VecDeque<(events::Event, Option<EventCompletionAction>)>>)
+       pub(super) fn remove_stale_payments(
+               &self, pending_events: &Mutex<VecDeque<(events::Event, Option<EventCompletionAction>)>>)
        {
-               // If an outbound payment was completed, and no pending HTLCs remain, we should remove it
-               // from the map. However, if we did that immediately when the last payment HTLC is claimed,
-               // this could race the user making a duplicate send_payment call and our idempotency
-               // guarantees would be violated. Instead, we wait a few timer ticks to do the actual
-               // removal. This should be more than sufficient to ensure the idempotency of any
-               // `send_payment` calls that were made at the same time the `PaymentSent` event was being
-               // processed.
                let mut pending_outbound_payments = self.pending_outbound_payments.lock().unwrap();
-               let pending_events = pending_events.lock().unwrap();
+               let mut pending_events = pending_events.lock().unwrap();
                pending_outbound_payments.retain(|payment_id, payment| {
+                       // If an outbound payment was completed, and no pending HTLCs remain, we should remove it
+                       // from the map. However, if we did that immediately when the last payment HTLC is claimed,
+                       // this could race the user making a duplicate send_payment call and our idempotency
+                       // guarantees would be violated. Instead, we wait a few timer ticks to do the actual
+                       // removal. This should be more than sufficient to ensure the idempotency of any
+                       // `send_payment` calls that were made at the same time the `PaymentSent` event was being
+                       // processed.
                        if let PendingOutboundPayment::Fulfilled { session_privs, timer_ticks_without_htlcs, .. } = payment {
                                let mut no_remaining_entries = session_privs.is_empty();
                                if no_remaining_entries {
@@ -1225,6 +1474,16 @@ impl OutboundPayments {
                                        *timer_ticks_without_htlcs = 0;
                                        true
                                }
+                       } else if let PendingOutboundPayment::AwaitingInvoice { timer_ticks_without_response, .. } = payment {
+                               *timer_ticks_without_response += 1;
+                               if *timer_ticks_without_response <= INVOICE_REQUEST_TIMEOUT_TICKS {
+                                       true
+                               } else {
+                                       pending_events.push_back(
+                                               (events::Event::InvoiceRequestFailed { payment_id: *payment_id }, None)
+                                       );
+                                       false
+                               }
                        } else { true }
                });
        }
@@ -1237,9 +1496,12 @@ impl OutboundPayments {
                pending_events: &Mutex<VecDeque<(events::Event, Option<EventCompletionAction>)>>, logger: &L,
        ) -> bool where L::Target: Logger {
                #[cfg(test)]
-               let (network_update, short_channel_id, payment_retryable, onion_error_code, onion_error_data) = onion_error.decode_onion_failure(secp_ctx, logger, &source);
+               let DecodedOnionFailure {
+                       network_update, short_channel_id, payment_retryable, onion_error_code, onion_error_data
+               } = onion_error.decode_onion_failure(secp_ctx, logger, &source);
                #[cfg(not(test))]
-               let (network_update, short_channel_id, payment_retryable, _, _) = onion_error.decode_onion_failure(secp_ctx, logger, &source);
+               let DecodedOnionFailure { network_update, short_channel_id, payment_retryable } =
+                       onion_error.decode_onion_failure(secp_ctx, logger, &source);
 
                let payment_is_probe = payment_is_probe(payment_hash, &payment_id, probing_cookie_secret);
                let mut session_priv_bytes = [0; 32];
@@ -1264,11 +1526,11 @@ impl OutboundPayments {
                let mut pending_retry_ev = false;
                let attempts_remaining = if let hash_map::Entry::Occupied(mut payment) = outbounds.entry(*payment_id) {
                        if !payment.get_mut().remove(&session_priv_bytes, Some(&path)) {
-                               log_trace!(logger, "Received duplicative fail for HTLC with payment_hash {}", log_bytes!(payment_hash.0));
+                               log_trace!(logger, "Received duplicative fail for HTLC with payment_hash {}", &payment_hash);
                                return false
                        }
                        if payment.get().is_fulfilled() {
-                               log_trace!(logger, "Received failure of HTLC with payment_hash {} after payment completion", log_bytes!(payment_hash.0));
+                               log_trace!(logger, "Received failure of HTLC with payment_hash {} after payment completion", &payment_hash);
                                return false
                        }
                        let mut is_retryable_now = payment.get().is_auto_retryable_now();
@@ -1302,11 +1564,11 @@ impl OutboundPayments {
                        }
                        is_retryable_now
                } else {
-                       log_trace!(logger, "Received duplicative fail for HTLC with payment_hash {}", log_bytes!(payment_hash.0));
+                       log_trace!(logger, "Received duplicative fail for HTLC with payment_hash {}", &payment_hash);
                        return false
                };
                core::mem::drop(outbounds);
-               log_trace!(logger, "Failing outbound payment HTLC with payment_hash {}", log_bytes!(payment_hash.0));
+               log_trace!(logger, "Failing outbound payment HTLC with payment_hash {}", &payment_hash);
 
                let path_failure = {
                        if payment_is_probe {
@@ -1367,6 +1629,11 @@ impl OutboundPayments {
                                        }, None));
                                        payment.remove();
                                }
+                       } else if let PendingOutboundPayment::AwaitingInvoice { .. } = payment.get() {
+                               pending_events.lock().unwrap().push_back((events::Event::InvoiceRequestFailed {
+                                       payment_id,
+                               }, None));
+                               payment.remove();
                        }
                }
        }
@@ -1420,6 +1687,7 @@ impl_writeable_tlv_based_enum_upgradable!(PendingOutboundPayment,
                (6, total_msat, required),
                (7, payment_metadata, option),
                (8, pending_amt_msat, required),
+               (9, custom_tlvs, optional_vec),
                (10, starting_block_height, required),
                (not_written, retry_strategy, (static_value, None)),
                (not_written, attempts, (static_value, PaymentAttempts::new())),
@@ -1429,6 +1697,14 @@ impl_writeable_tlv_based_enum_upgradable!(PendingOutboundPayment,
                (1, reason, option),
                (2, payment_hash, required),
        },
+       (5, AwaitingInvoice) => {
+               (0, timer_ticks_without_response, required),
+               (2, retry_strategy, required),
+       },
+       (7, InvoiceReceived) => {
+               (0, payment_hash, required),
+               (2, retry_strategy, required),
+       },
 );
 
 #[cfg(test)]
@@ -1441,15 +1717,40 @@ mod tests {
        use crate::ln::channelmanager::{PaymentId, RecipientOnionFields};
        use crate::ln::features::{ChannelFeatures, NodeFeatures};
        use crate::ln::msgs::{ErrorAction, LightningError};
-       use crate::ln::outbound_payment::{OutboundPayments, Retry, RetryableSendFailure};
+       use crate::ln::outbound_payment::{Bolt12PaymentError, INVOICE_REQUEST_TIMEOUT_TICKS, OutboundPayments, Retry, RetryableSendFailure};
+       use crate::offers::invoice::DEFAULT_RELATIVE_EXPIRY;
+       use crate::offers::offer::OfferBuilder;
+       use crate::offers::test_utils::*;
        use crate::routing::gossip::NetworkGraph;
        use crate::routing::router::{InFlightHtlcs, Path, PaymentParameters, Route, RouteHop, RouteParameters};
-       use crate::sync::{Arc, Mutex};
+       use crate::sync::{Arc, Mutex, RwLock};
        use crate::util::errors::APIError;
        use crate::util::test_utils;
 
        use alloc::collections::VecDeque;
 
+       #[test]
+       fn test_recipient_onion_fields_with_custom_tlvs() {
+               let onion_fields = RecipientOnionFields::spontaneous_empty();
+
+               let bad_type_range_tlvs = vec![
+                       (0, vec![42]),
+                       (1, vec![42; 32]),
+               ];
+               assert!(onion_fields.clone().with_custom_tlvs(bad_type_range_tlvs).is_err());
+
+               let keysend_tlv = vec![
+                       (5482373484, vec![42; 32]),
+               ];
+               assert!(onion_fields.clone().with_custom_tlvs(keysend_tlv).is_err());
+
+               let good_tlvs = vec![
+                       ((1 << 16) + 1, vec![42]),
+                       ((1 << 16) + 3, vec![42; 32]),
+               ];
+               assert!(onion_fields.with_custom_tlvs(good_tlvs).is_ok());
+       }
+
        #[test]
        #[cfg(feature = "std")]
        fn fails_paying_after_expiration() {
@@ -1461,7 +1762,7 @@ mod tests {
                let outbound_payments = OutboundPayments::new();
                let logger = test_utils::TestLogger::new();
                let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, &logger));
-               let scorer = Mutex::new(test_utils::TestScorer::new());
+               let scorer = RwLock::new(test_utils::TestScorer::new());
                let router = test_utils::TestRouter::new(network_graph, &scorer);
                let secp_ctx = Secp256k1::new();
                let keys_manager = test_utils::TestKeysInterface::new(&[0; 32], Network::Testnet);
@@ -1471,17 +1772,14 @@ mod tests {
                                PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()),
                                0
                        ).with_expiry_time(past_expiry_time);
-               let expired_route_params = RouteParameters {
-                       payment_params,
-                       final_value_msat: 0,
-               };
+               let expired_route_params = RouteParameters::from_payment_params_and_value(payment_params, 0);
                let pending_events = Mutex::new(VecDeque::new());
                if on_retry {
                        outbound_payments.add_new_pending_payment(PaymentHash([0; 32]), RecipientOnionFields::spontaneous_empty(),
-                               PaymentId([0; 32]), None, &Route { paths: vec![], payment_params: None },
+                               PaymentId([0; 32]), None, &Route { paths: vec![], route_params: None },
                                Some(Retry::Attempts(1)), Some(expired_route_params.payment_params.clone()),
                                &&keys_manager, 0).unwrap();
-                       outbound_payments.retry_payment_internal(
+                       outbound_payments.find_route_and_send_payment(
                                PaymentHash([0; 32]), PaymentId([0; 32]), expired_route_params, &&router, vec![],
                                &|| InFlightHtlcs::new(), &&keys_manager, &&keys_manager, 0, &&logger, &pending_events,
                                &|_| Ok(()));
@@ -1508,27 +1806,24 @@ mod tests {
                let outbound_payments = OutboundPayments::new();
                let logger = test_utils::TestLogger::new();
                let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, &logger));
-               let scorer = Mutex::new(test_utils::TestScorer::new());
+               let scorer = RwLock::new(test_utils::TestScorer::new());
                let router = test_utils::TestRouter::new(network_graph, &scorer);
                let secp_ctx = Secp256k1::new();
                let keys_manager = test_utils::TestKeysInterface::new(&[0; 32], Network::Testnet);
 
                let payment_params = PaymentParameters::from_node_id(
                        PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0);
-               let route_params = RouteParameters {
-                       payment_params,
-                       final_value_msat: 0,
-               };
+               let route_params = RouteParameters::from_payment_params_and_value(payment_params, 0);
                router.expect_find_route(route_params.clone(),
                        Err(LightningError { err: String::new(), action: ErrorAction::IgnoreError }));
 
                let pending_events = Mutex::new(VecDeque::new());
                if on_retry {
                        outbound_payments.add_new_pending_payment(PaymentHash([0; 32]), RecipientOnionFields::spontaneous_empty(),
-                               PaymentId([0; 32]), None, &Route { paths: vec![], payment_params: None },
+                               PaymentId([0; 32]), None, &Route { paths: vec![], route_params: None },
                                Some(Retry::Attempts(1)), Some(route_params.payment_params.clone()),
                                &&keys_manager, 0).unwrap();
-                       outbound_payments.retry_payment_internal(
+                       outbound_payments.find_route_and_send_payment(
                                PaymentHash([0; 32]), PaymentId([0; 32]), route_params, &&router, vec![],
                                &|| InFlightHtlcs::new(), &&keys_manager, &&keys_manager, 0, &&logger, &pending_events,
                                &|_| Ok(()));
@@ -1550,7 +1845,7 @@ mod tests {
                let outbound_payments = OutboundPayments::new();
                let logger = test_utils::TestLogger::new();
                let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, &logger));
-               let scorer = Mutex::new(test_utils::TestScorer::new());
+               let scorer = RwLock::new(test_utils::TestScorer::new());
                let router = test_utils::TestRouter::new(network_graph, &scorer);
                let secp_ctx = Secp256k1::new();
                let keys_manager = test_utils::TestKeysInterface::new(&[0; 32], Network::Testnet);
@@ -1558,10 +1853,7 @@ mod tests {
                let sender_pk = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
                let receiver_pk = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[43; 32]).unwrap());
                let payment_params = PaymentParameters::from_node_id(sender_pk, 0);
-               let route_params = RouteParameters {
-                       payment_params: payment_params.clone(),
-                       final_value_msat: 0,
-               };
+               let route_params = RouteParameters::from_payment_params_and_value(payment_params.clone(), 0);
                let failed_scid = 42;
                let route = Route {
                        paths: vec![Path { hops: vec![RouteHop {
@@ -1571,8 +1863,9 @@ mod tests {
                                channel_features: ChannelFeatures::empty(),
                                fee_msat: 0,
                                cltv_expiry_delta: 0,
+                               maybe_announced_channel: true,
                        }], blinded_tail: None }],
-                       payment_params: Some(payment_params),
+                       route_params: Some(route_params.clone()),
                };
                router.expect_find_route(route_params.clone(), Ok(route.clone()));
                let mut route_params_w_failed_scid = route_params.clone();
@@ -1625,4 +1918,294 @@ mod tests {
                } else { panic!("Unexpected event"); }
                if let Event::PaymentFailed { .. } = events[1].0 { } else { panic!("Unexpected event"); }
        }
+
+       #[test]
+       fn removes_stale_awaiting_invoice() {
+               let pending_events = Mutex::new(VecDeque::new());
+               let outbound_payments = OutboundPayments::new();
+               let payment_id = PaymentId([0; 32]);
+
+               assert!(!outbound_payments.has_pending_payments());
+               assert!(outbound_payments.add_new_awaiting_invoice(payment_id, Retry::Attempts(0)).is_ok());
+               assert!(outbound_payments.has_pending_payments());
+
+               for _ in 0..INVOICE_REQUEST_TIMEOUT_TICKS {
+                       outbound_payments.remove_stale_payments(&pending_events);
+                       assert!(outbound_payments.has_pending_payments());
+                       assert!(pending_events.lock().unwrap().is_empty());
+               }
+
+               outbound_payments.remove_stale_payments(&pending_events);
+               assert!(!outbound_payments.has_pending_payments());
+               assert!(!pending_events.lock().unwrap().is_empty());
+               assert_eq!(
+                       pending_events.lock().unwrap().pop_front(),
+                       Some((Event::InvoiceRequestFailed { payment_id }, None)),
+               );
+               assert!(pending_events.lock().unwrap().is_empty());
+
+               assert!(outbound_payments.add_new_awaiting_invoice(payment_id, Retry::Attempts(0)).is_ok());
+               assert!(outbound_payments.has_pending_payments());
+
+               assert!(outbound_payments.add_new_awaiting_invoice(payment_id, Retry::Attempts(0)).is_err());
+       }
+
+       #[test]
+       fn removes_abandoned_awaiting_invoice() {
+               let pending_events = Mutex::new(VecDeque::new());
+               let outbound_payments = OutboundPayments::new();
+               let payment_id = PaymentId([0; 32]);
+
+               assert!(!outbound_payments.has_pending_payments());
+               assert!(outbound_payments.add_new_awaiting_invoice(payment_id, Retry::Attempts(0)).is_ok());
+               assert!(outbound_payments.has_pending_payments());
+
+               outbound_payments.abandon_payment(
+                       payment_id, PaymentFailureReason::UserAbandoned, &pending_events
+               );
+               assert!(!outbound_payments.has_pending_payments());
+               assert!(!pending_events.lock().unwrap().is_empty());
+               assert_eq!(
+                       pending_events.lock().unwrap().pop_front(),
+                       Some((Event::InvoiceRequestFailed { payment_id }, None)),
+               );
+               assert!(pending_events.lock().unwrap().is_empty());
+       }
+
+       #[cfg(feature = "std")]
+       #[test]
+       fn fails_sending_payment_for_expired_bolt12_invoice() {
+               let logger = test_utils::TestLogger::new();
+               let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, &logger));
+               let scorer = RwLock::new(test_utils::TestScorer::new());
+               let router = test_utils::TestRouter::new(network_graph, &scorer);
+               let keys_manager = test_utils::TestKeysInterface::new(&[0; 32], Network::Testnet);
+
+               let pending_events = Mutex::new(VecDeque::new());
+               let outbound_payments = OutboundPayments::new();
+               let payment_id = PaymentId([0; 32]);
+
+               assert!(outbound_payments.add_new_awaiting_invoice(payment_id, Retry::Attempts(0)).is_ok());
+               assert!(outbound_payments.has_pending_payments());
+
+               let created_at = now() - DEFAULT_RELATIVE_EXPIRY;
+               let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
+                       .amount_msats(1000)
+                       .build().unwrap()
+                       .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
+                       .build().unwrap()
+                       .sign(payer_sign).unwrap()
+                       .respond_with_no_std(payment_paths(), payment_hash(), created_at).unwrap()
+                       .build().unwrap()
+                       .sign(recipient_sign).unwrap();
+
+               assert_eq!(
+                       outbound_payments.send_payment_for_bolt12_invoice(
+                               &invoice, payment_id, &&router, vec![], || InFlightHtlcs::new(), &&keys_manager,
+                               &&keys_manager, 0, &&logger, &pending_events, |_| panic!()
+                       ),
+                       Ok(()),
+               );
+               assert!(!outbound_payments.has_pending_payments());
+
+               let payment_hash = invoice.payment_hash();
+               let reason = Some(PaymentFailureReason::PaymentExpired);
+
+               assert!(!pending_events.lock().unwrap().is_empty());
+               assert_eq!(
+                       pending_events.lock().unwrap().pop_front(),
+                       Some((Event::PaymentFailed { payment_id, payment_hash, reason }, None)),
+               );
+               assert!(pending_events.lock().unwrap().is_empty());
+       }
+
+       #[test]
+       fn fails_finding_route_for_bolt12_invoice() {
+               let logger = test_utils::TestLogger::new();
+               let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, &logger));
+               let scorer = RwLock::new(test_utils::TestScorer::new());
+               let router = test_utils::TestRouter::new(network_graph, &scorer);
+               let keys_manager = test_utils::TestKeysInterface::new(&[0; 32], Network::Testnet);
+
+               let pending_events = Mutex::new(VecDeque::new());
+               let outbound_payments = OutboundPayments::new();
+               let payment_id = PaymentId([0; 32]);
+
+               assert!(outbound_payments.add_new_awaiting_invoice(payment_id, Retry::Attempts(0)).is_ok());
+               assert!(outbound_payments.has_pending_payments());
+
+               let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
+                       .amount_msats(1000)
+                       .build().unwrap()
+                       .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
+                       .build().unwrap()
+                       .sign(payer_sign).unwrap()
+                       .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
+                       .build().unwrap()
+                       .sign(recipient_sign).unwrap();
+
+               router.expect_find_route(
+                       RouteParameters {
+                               payment_params: PaymentParameters::from_bolt12_invoice(&invoice),
+                               final_value_msat: invoice.amount_msats(),
+                       },
+                       Err(LightningError { err: String::new(), action: ErrorAction::IgnoreError }),
+               );
+
+               assert_eq!(
+                       outbound_payments.send_payment_for_bolt12_invoice(
+                               &invoice, payment_id, &&router, vec![], || InFlightHtlcs::new(), &&keys_manager,
+                               &&keys_manager, 0, &&logger, &pending_events, |_| panic!()
+                       ),
+                       Ok(()),
+               );
+               assert!(!outbound_payments.has_pending_payments());
+
+               let payment_hash = invoice.payment_hash();
+               let reason = Some(PaymentFailureReason::RouteNotFound);
+
+               assert!(!pending_events.lock().unwrap().is_empty());
+               assert_eq!(
+                       pending_events.lock().unwrap().pop_front(),
+                       Some((Event::PaymentFailed { payment_id, payment_hash, reason }, None)),
+               );
+               assert!(pending_events.lock().unwrap().is_empty());
+       }
+
+       #[test]
+       fn fails_paying_for_bolt12_invoice() {
+               let logger = test_utils::TestLogger::new();
+               let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, &logger));
+               let scorer = RwLock::new(test_utils::TestScorer::new());
+               let router = test_utils::TestRouter::new(network_graph, &scorer);
+               let keys_manager = test_utils::TestKeysInterface::new(&[0; 32], Network::Testnet);
+
+               let pending_events = Mutex::new(VecDeque::new());
+               let outbound_payments = OutboundPayments::new();
+               let payment_id = PaymentId([0; 32]);
+
+               assert!(outbound_payments.add_new_awaiting_invoice(payment_id, Retry::Attempts(0)).is_ok());
+               assert!(outbound_payments.has_pending_payments());
+
+               let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
+                       .amount_msats(1000)
+                       .build().unwrap()
+                       .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
+                       .build().unwrap()
+                       .sign(payer_sign).unwrap()
+                       .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
+                       .build().unwrap()
+                       .sign(recipient_sign).unwrap();
+
+               let route_params = RouteParameters {
+                       payment_params: PaymentParameters::from_bolt12_invoice(&invoice),
+                       final_value_msat: invoice.amount_msats(),
+               };
+               router.expect_find_route(
+                       route_params.clone(), Ok(Route { paths: vec![], route_params: Some(route_params) })
+               );
+
+               assert_eq!(
+                       outbound_payments.send_payment_for_bolt12_invoice(
+                               &invoice, payment_id, &&router, vec![], || InFlightHtlcs::new(), &&keys_manager,
+                               &&keys_manager, 0, &&logger, &pending_events, |_| panic!()
+                       ),
+                       Ok(()),
+               );
+               assert!(!outbound_payments.has_pending_payments());
+
+               let payment_hash = invoice.payment_hash();
+               let reason = Some(PaymentFailureReason::UnexpectedError);
+
+               assert!(!pending_events.lock().unwrap().is_empty());
+               assert_eq!(
+                       pending_events.lock().unwrap().pop_front(),
+                       Some((Event::PaymentFailed { payment_id, payment_hash, reason }, None)),
+               );
+               assert!(pending_events.lock().unwrap().is_empty());
+       }
+
+       #[test]
+       fn sends_payment_for_bolt12_invoice() {
+               let logger = test_utils::TestLogger::new();
+               let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, &logger));
+               let scorer = RwLock::new(test_utils::TestScorer::new());
+               let router = test_utils::TestRouter::new(network_graph, &scorer);
+               let keys_manager = test_utils::TestKeysInterface::new(&[0; 32], Network::Testnet);
+
+               let pending_events = Mutex::new(VecDeque::new());
+               let outbound_payments = OutboundPayments::new();
+               let payment_id = PaymentId([0; 32]);
+
+               let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
+                       .amount_msats(1000)
+                       .build().unwrap()
+                       .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
+                       .build().unwrap()
+                       .sign(payer_sign).unwrap()
+                       .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
+                       .build().unwrap()
+                       .sign(recipient_sign).unwrap();
+
+               let route_params = RouteParameters {
+                       payment_params: PaymentParameters::from_bolt12_invoice(&invoice),
+                       final_value_msat: invoice.amount_msats(),
+               };
+               router.expect_find_route(
+                       route_params.clone(),
+                       Ok(Route {
+                               paths: vec![
+                                       Path {
+                                               hops: vec![
+                                                       RouteHop {
+                                                               pubkey: recipient_pubkey(),
+                                                               node_features: NodeFeatures::empty(),
+                                                               short_channel_id: 42,
+                                                               channel_features: ChannelFeatures::empty(),
+                                                               fee_msat: invoice.amount_msats(),
+                                                               cltv_expiry_delta: 0,
+                                                               maybe_announced_channel: true,
+                                                       }
+                                               ],
+                                               blinded_tail: None,
+                                       }
+                               ],
+                               route_params: Some(route_params),
+                       })
+               );
+
+               assert!(!outbound_payments.has_pending_payments());
+               assert_eq!(
+                       outbound_payments.send_payment_for_bolt12_invoice(
+                               &invoice, payment_id, &&router, vec![], || InFlightHtlcs::new(), &&keys_manager,
+                               &&keys_manager, 0, &&logger, &pending_events, |_| panic!()
+                       ),
+                       Err(Bolt12PaymentError::UnexpectedInvoice),
+               );
+               assert!(!outbound_payments.has_pending_payments());
+               assert!(pending_events.lock().unwrap().is_empty());
+
+               assert!(outbound_payments.add_new_awaiting_invoice(payment_id, Retry::Attempts(0)).is_ok());
+               assert!(outbound_payments.has_pending_payments());
+
+               assert_eq!(
+                       outbound_payments.send_payment_for_bolt12_invoice(
+                               &invoice, payment_id, &&router, vec![], || InFlightHtlcs::new(), &&keys_manager,
+                               &&keys_manager, 0, &&logger, &pending_events, |_| Ok(())
+                       ),
+                       Ok(()),
+               );
+               assert!(outbound_payments.has_pending_payments());
+               assert!(pending_events.lock().unwrap().is_empty());
+
+               assert_eq!(
+                       outbound_payments.send_payment_for_bolt12_invoice(
+                               &invoice, payment_id, &&router, vec![], || InFlightHtlcs::new(), &&keys_manager,
+                               &&keys_manager, 0, &&logger, &pending_events, |_| panic!()
+                       ),
+                       Err(Bolt12PaymentError::DuplicateInvoice),
+               );
+               assert!(outbound_payments.has_pending_payments());
+               assert!(pending_events.lock().unwrap().is_empty());
+       }
 }