InboundOnionErr fields public
[rust-lightning] / lightning / src / ln / channelmanager.rs
index 3810cfb8171eeca169e29eb5b36f68ca5b23fdfe..d27dc9d3a7d891209c2a87a72d7786dc5b54369b 100644 (file)
@@ -30,6 +30,8 @@ use bitcoin::secp256k1::{SecretKey,PublicKey};
 use bitcoin::secp256k1::Secp256k1;
 use bitcoin::{LockTime, secp256k1, Sequence};
 
+use crate::blinded_path::BlindedPath;
+use crate::blinded_path::payment::{PaymentConstraints, ReceiveTlvs};
 use crate::chain;
 use crate::chain::{Confirm, ChannelMonitorUpdateStatus, Watch, BestBlock};
 use crate::chain::chaininterface::{BroadcasterInterface, ConfirmationTarget, FeeEstimator, LowerBoundedFeeEstimator};
@@ -41,7 +43,7 @@ use crate::events::{Event, EventHandler, EventsProvider, MessageSendEvent, Messa
 // construct one themselves.
 use crate::ln::{inbound_payment, ChannelId, PaymentHash, PaymentPreimage, PaymentSecret};
 use crate::ln::channel::{Channel, ChannelPhase, ChannelContext, ChannelError, ChannelUpdateStatus, ShutdownResult, UnfundedChannelContext, UpdateFulfillCommitFetch, OutboundV1Channel, InboundV1Channel};
-use crate::ln::features::{ChannelFeatures, ChannelTypeFeatures, InitFeatures, NodeFeatures};
+use crate::ln::features::{Bolt12InvoiceFeatures, ChannelFeatures, ChannelTypeFeatures, InitFeatures, NodeFeatures};
 #[cfg(any(feature = "_test_utils", test))]
 use crate::ln::features::Bolt11InvoiceFeatures;
 use crate::routing::gossip::NetworkGraph;
@@ -53,11 +55,15 @@ use crate::ln::onion_utils::HTLCFailReason;
 use crate::ln::msgs::{ChannelMessageHandler, DecodeError, LightningError};
 #[cfg(test)]
 use crate::ln::outbound_payment;
-use crate::ln::outbound_payment::{OutboundPayments, PaymentAttempts, PendingOutboundPayment, SendAlongPathArgs};
+use crate::ln::outbound_payment::{Bolt12PaymentError, OutboundPayments, PaymentAttempts, PendingOutboundPayment, SendAlongPathArgs, StaleExpiration};
 use crate::ln::wire::Encode;
-use crate::offers::offer::{DerivedMetadata, OfferBuilder};
+use crate::offers::invoice::{BlindedPayInfo, Bolt12Invoice, DEFAULT_RELATIVE_EXPIRY, DerivedSigningPubkey, InvoiceBuilder};
+use crate::offers::invoice_error::InvoiceError;
+use crate::offers::merkle::SignError;
+use crate::offers::offer::{DerivedMetadata, Offer, OfferBuilder};
 use crate::offers::parse::Bolt12SemanticError;
-use crate::offers::refund::RefundBuilder;
+use crate::offers::refund::{Refund, RefundBuilder};
+use crate::onion_message::{Destination, OffersMessage, OffersMessageHandler, PendingOnionMessage, new_pending_onion_message};
 use crate::sign::{EntropySource, KeysManager, NodeSigner, Recipient, SignerProvider, WriteableEcdsaChannelSigner};
 use crate::util::config::{UserConfig, ChannelConfig, ChannelConfigUpdate};
 use crate::util::wakers::{Future, Notifier};
@@ -100,47 +106,63 @@ use crate::ln::script::ShutdownScript;
 // Alternatively, we can fill an outbound HTLC with a HTLCSource::OutboundRoute indicating this is
 // our payment, which we can use to decode errors or inform the user that the payment was sent.
 
+/// Routing info for an inbound HTLC onion.
 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
-pub(super) enum PendingHTLCRouting {
+pub enum PendingHTLCRouting {
+       /// A forwarded HTLC.
        Forward {
+               /// BOLT 4 onion packet.
                onion_packet: msgs::OnionPacket,
                /// The SCID from the onion that we should forward to. This could be a real SCID or a fake one
                /// generated using `get_fake_scid` from the scid_utils::fake_scid module.
                short_channel_id: u64, // This should be NonZero<u64> eventually when we bump MSRV
        },
+       /// An HTLC paid to an invoice we generated.
        Receive {
+               /// Payment secret and total msat received.
                payment_data: msgs::FinalOnionHopData,
+               /// See [`RecipientOnionFields::payment_metadata`] for more info.
                payment_metadata: Option<Vec<u8>>,
-               incoming_cltv_expiry: u32, // Used to track when we should expire pending HTLCs that go unclaimed
+               /// Used to track when we should expire pending HTLCs that go unclaimed.
+               incoming_cltv_expiry: u32,
+               /// Optional shared secret for phantom node.
                phantom_shared_secret: Option<[u8; 32]>,
                /// See [`RecipientOnionFields::custom_tlvs`] for more info.
                custom_tlvs: Vec<(u64, Vec<u8>)>,
        },
+       /// Incoming keysend (sender provided the preimage in a TLV).
        ReceiveKeysend {
                /// This was added in 0.0.116 and will break deserialization on downgrades.
                payment_data: Option<msgs::FinalOnionHopData>,
+               /// Preimage for this onion payment.
                payment_preimage: PaymentPreimage,
+               /// See [`RecipientOnionFields::payment_metadata`] for more info.
                payment_metadata: Option<Vec<u8>>,
+               /// CLTV expiry of the incoming HTLC.
                incoming_cltv_expiry: u32, // Used to track when we should expire pending HTLCs that go unclaimed
                /// See [`RecipientOnionFields::custom_tlvs`] for more info.
                custom_tlvs: Vec<(u64, Vec<u8>)>,
        },
 }
 
+/// Full details of an incoming HTLC, including routing info.
 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
-pub(super) struct PendingHTLCInfo {
-       pub(super) routing: PendingHTLCRouting,
-       pub(super) incoming_shared_secret: [u8; 32],
+pub struct PendingHTLCInfo {
+       /// Further routing details based on whether the HTLC is being forwarded or received.
+       pub routing: PendingHTLCRouting,
+       /// Shared secret from the previous hop.
+       pub incoming_shared_secret: [u8; 32],
        payment_hash: PaymentHash,
        /// Amount received
-       pub(super) incoming_amt_msat: Option<u64>, // Added in 0.0.113
+       pub incoming_amt_msat: Option<u64>, // Added in 0.0.113
        /// Sender intended amount to forward or receive (actual amount received
        /// may overshoot this in either case)
-       pub(super) outgoing_amt_msat: u64,
-       pub(super) outgoing_cltv_value: u32,
+       pub outgoing_amt_msat: u64,
+       /// Outgoing CLTV height.
+       pub outgoing_cltv_value: u32,
        /// The fee being skimmed off the top of this HTLC. If this is a forward, it'll be the fee we are
        /// skimming. If we're receiving this HTLC, it's the fee that our counterparty skimmed.
-       pub(super) skimmed_fee_msat: Option<u64>,
+       pub skimmed_fee_msat: Option<u64>,
 }
 
 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
@@ -372,10 +394,14 @@ impl HTLCSource {
        }
 }
 
-struct InboundOnionErr {
-       err_code: u16,
-       err_data: Vec<u8>,
-       msg: &'static str,
+/// Invalid inbound onion payment.
+pub struct InboundOnionErr {
+       /// BOLT 4 error code.
+       pub err_code: u16,
+       /// Data attached to this error.
+       pub err_data: Vec<u8>,
+       /// Error message text.
+       pub msg: &'static str,
 }
 
 /// This enum is used to specify which error data to send to peers when failing back an HTLC
@@ -451,7 +477,7 @@ impl MsgHandleErrInternal {
        #[inline]
        fn from_finish_shutdown(err: String, channel_id: ChannelId, user_channel_id: u128, shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>, channel_capacity: u64) -> Self {
                let err_msg = msgs::ErrorMessage { channel_id, data: err.clone() };
-               let action = if let (Some(_), ..) = &shutdown_res {
+               let action = if shutdown_res.monitor_update.is_some() {
                        // We have a closing `ChannelMonitorUpdate`, which means the channel was funded and we
                        // should disconnect our peer such that we force them to broadcast their latest
                        // commitment upon reconnecting.
@@ -567,6 +593,7 @@ struct ClaimablePayments {
 /// usually because we're running pre-full-init. They are handled immediately once we detect we are
 /// running normally, and specifically must be processed before any other non-background
 /// [`ChannelMonitorUpdate`]s are applied.
+#[derive(Debug)]
 enum BackgroundEvent {
        /// Handle a ChannelMonitorUpdate which closes the channel or for an already-closed channel.
        /// This is only separated from [`Self::MonitorUpdateRegeneratedOnStartup`] as the
@@ -619,10 +646,34 @@ pub(crate) enum MonitorUpdateCompletionAction {
                event: events::Event,
                downstream_counterparty_and_funding_outpoint: Option<(PublicKey, OutPoint, RAAMonitorUpdateBlockingAction)>,
        },
+       /// Indicates we should immediately resume the operation of another channel, unless there is
+       /// some other reason why the channel is blocked. In practice this simply means immediately
+       /// removing the [`RAAMonitorUpdateBlockingAction`] provided from the blocking set.
+       ///
+       /// This is usually generated when we've forwarded an HTLC and want to block the outbound edge
+       /// from completing a monitor update which removes the payment preimage until the inbound edge
+       /// completes a monitor update containing the payment preimage. However, we use this variant
+       /// instead of [`Self::EmitEventAndFreeOtherChannel`] when we discover that the claim was in
+       /// fact duplicative and we simply want to resume the outbound edge channel immediately.
+       ///
+       /// This variant should thus never be written to disk, as it is processed inline rather than
+       /// stored for later processing.
+       FreeOtherChannelImmediately {
+               downstream_counterparty_node_id: PublicKey,
+               downstream_funding_outpoint: OutPoint,
+               blocking_action: RAAMonitorUpdateBlockingAction,
+       },
 }
 
 impl_writeable_tlv_based_enum_upgradable!(MonitorUpdateCompletionAction,
        (0, PaymentClaimed) => { (0, payment_hash, required) },
+       // Note that FreeOtherChannelImmediately should never be written - we were supposed to free
+       // *immediately*. However, for simplicity we implement read/write here.
+       (1, FreeOtherChannelImmediately) => {
+               (0, downstream_counterparty_node_id, required),
+               (2, downstream_funding_outpoint, required),
+               (4, blocking_action, required),
+       },
        (2, EmitEventAndFreeOtherChannel) => {
                (0, event, upgradable_required),
                // LDK prior to 0.0.116 did not have this field as the monitor update application order was
@@ -796,7 +847,8 @@ struct PendingInboundPayment {
 /// or, respectively, [`Router`] for its router, but this type alias chooses the concrete types
 /// of [`KeysManager`] and [`DefaultRouter`].
 ///
-/// This is not exported to bindings users as Arcs don't make sense in bindings
+/// This is not exported to bindings users as type aliases aren't supported in most languages.
+#[cfg(not(c_bindings))]
 pub type SimpleArcChannelManager<M, T, F, L> = ChannelManager<
        Arc<M>,
        Arc<T>,
@@ -824,7 +876,8 @@ pub type SimpleArcChannelManager<M, T, F, L> = ChannelManager<
 /// or, respectively, [`Router`]  for its router, but this type alias chooses the concrete types
 /// of [`KeysManager`] and [`DefaultRouter`].
 ///
-/// This is not exported to bindings users as Arcs don't make sense in bindings
+/// This is not exported to bindings users as type aliases aren't supported in most languages.
+#[cfg(not(c_bindings))]
 pub type SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, 'f, 'g, 'h, M, T, F, L> =
        ChannelManager<
                &'a M,
@@ -982,6 +1035,8 @@ where
 //
 // Lock order tree:
 //
+// `pending_offers_messages`
+//
 // `total_consistency_lock`
 //  |
 //  |__`forward_htlcs`
@@ -989,26 +1044,26 @@ where
 //  |   |__`pending_intercepted_htlcs`
 //  |
 //  |__`per_peer_state`
-//  |   |
-//  |   |__`pending_inbound_payments`
-//  |       |
-//  |       |__`claimable_payments`
-//  |       |
-//  |       |__`pending_outbound_payments` // This field's struct contains a map of pending outbounds
-//  |           |
-//  |           |__`peer_state`
-//  |               |
-//  |               |__`id_to_peer`
-//  |               |
-//  |               |__`short_to_chan_info`
-//  |               |
-//  |               |__`outbound_scid_aliases`
-//  |               |
-//  |               |__`best_block`
-//  |               |
-//  |               |__`pending_events`
-//  |                   |
-//  |                   |__`pending_background_events`
+//      |
+//      |__`pending_inbound_payments`
+//          |
+//          |__`claimable_payments`
+//          |
+//          |__`pending_outbound_payments` // This field's struct contains a map of pending outbounds
+//              |
+//              |__`peer_state`
+//                  |
+//                  |__`id_to_peer`
+//                  |
+//                  |__`short_to_chan_info`
+//                  |
+//                  |__`outbound_scid_aliases`
+//                  |
+//                  |__`best_block`
+//                  |
+//                  |__`pending_events`
+//                      |
+//                      |__`pending_background_events`
 //
 pub struct ChannelManager<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref>
 where
@@ -1220,6 +1275,8 @@ where
        event_persist_notifier: Notifier,
        needs_persist_flag: AtomicBool,
 
+       pending_offers_messages: Mutex<Vec<PendingOnionMessage<OffersMessage>>>,
+
        entropy_source: ES,
        node_signer: NS,
        signer_provider: SP,
@@ -2300,6 +2357,8 @@ where
                        needs_persist_flag: AtomicBool::new(false),
                        funding_batch_states: Mutex::new(BTreeMap::new()),
 
+                       pending_offers_messages: Mutex::new(Vec::new()),
+
                        entropy_source,
                        node_signer,
                        signer_provider,
@@ -2563,7 +2622,7 @@ where
                let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
 
                let mut failed_htlcs: Vec<(HTLCSource, PaymentHash)>;
-               let mut shutdown_result = None;
+               let shutdown_result;
                loop {
                        let per_peer_state = self.per_peer_state.read().unwrap();
 
@@ -2578,10 +2637,11 @@ where
                                        if let ChannelPhase::Funded(chan) = chan_phase_entry.get_mut() {
                                                let funding_txo_opt = chan.context.get_funding_txo();
                                                let their_features = &peer_state.latest_features;
-                                               let unbroadcasted_batch_funding_txid = chan.context.unbroadcasted_batch_funding_txid();
-                                               let (shutdown_msg, mut monitor_update_opt, htlcs) =
+                                               let (shutdown_msg, mut monitor_update_opt, htlcs, local_shutdown_result) =
                                                        chan.get_shutdown(&self.signer_provider, their_features, target_feerate_sats_per_1000_weight, override_shutdown_script)?;
                                                failed_htlcs = htlcs;
+                                               shutdown_result = local_shutdown_result;
+                                               debug_assert_eq!(shutdown_result.is_some(), chan.is_shutdown());
 
                                                // We can send the `shutdown` message before updating the `ChannelMonitor`
                                                // here as we don't need the monitor update to complete until we send a
@@ -2609,7 +2669,6 @@ where
                                                                        });
                                                                }
                                                                self.issue_channel_close_events(&chan.context, ClosureReason::HolderForceClosed);
-                                                               shutdown_result = Some((None, Vec::new(), unbroadcasted_batch_funding_txid));
                                                        }
                                                }
                                                break;
@@ -2644,11 +2703,11 @@ where
        /// will be accepted on the given channel, and after additional timeout/the closing of all
        /// pending HTLCs, the channel will be closed on chain.
        ///
-       ///  * If we are the channel initiator, we will pay between our [`Background`] and
-       ///    [`ChannelConfig::force_close_avoidance_max_fee_satoshis`] plus our [`Normal`] fee
-       ///    estimate.
+       ///  * If we are the channel initiator, we will pay between our [`ChannelCloseMinimum`] and
+       ///    [`ChannelConfig::force_close_avoidance_max_fee_satoshis`] plus our [`NonAnchorChannelFee`]
+       ///    fee estimate.
        ///  * If our counterparty is the channel initiator, we will require a channel closing
-       ///    transaction feerate of at least our [`Background`] feerate or the feerate which
+       ///    transaction feerate of at least our [`ChannelCloseMinimum`] feerate or the feerate which
        ///    would appear on a force-closure transaction, whichever is lower. We will allow our
        ///    counterparty to pay as much fee as they'd like, however.
        ///
@@ -2660,8 +2719,8 @@ where
        /// channel.
        ///
        /// [`ChannelConfig::force_close_avoidance_max_fee_satoshis`]: crate::util::config::ChannelConfig::force_close_avoidance_max_fee_satoshis
-       /// [`Background`]: crate::chain::chaininterface::ConfirmationTarget::Background
-       /// [`Normal`]: crate::chain::chaininterface::ConfirmationTarget::Normal
+       /// [`ChannelCloseMinimum`]: crate::chain::chaininterface::ConfirmationTarget::ChannelCloseMinimum
+       /// [`NonAnchorChannelFee`]: crate::chain::chaininterface::ConfirmationTarget::NonAnchorChannelFee
        /// [`SendShutdown`]: crate::events::MessageSendEvent::SendShutdown
        pub fn close_channel(&self, channel_id: &ChannelId, counterparty_node_id: &PublicKey) -> Result<(), APIError> {
                self.close_channel_internal(channel_id, counterparty_node_id, None, None)
@@ -2675,8 +2734,8 @@ where
        /// the channel being closed or not:
        ///  * If we are the channel initiator, we will pay at least this feerate on the closing
        ///    transaction. The upper-bound is set by
-       ///    [`ChannelConfig::force_close_avoidance_max_fee_satoshis`] plus our [`Normal`] fee
-       ///    estimate (or `target_feerate_sat_per_1000_weight`, if it is greater).
+       ///    [`ChannelConfig::force_close_avoidance_max_fee_satoshis`] plus our [`NonAnchorChannelFee`]
+       ///    fee estimate (or `target_feerate_sat_per_1000_weight`, if it is greater).
        ///  * If our counterparty is the channel initiator, we will refuse to accept a channel closure
        ///    transaction feerate below `target_feerate_sat_per_1000_weight` (or the feerate which
        ///    will appear on a force-closure transaction, whichever is lower).
@@ -2694,29 +2753,27 @@ where
        /// channel.
        ///
        /// [`ChannelConfig::force_close_avoidance_max_fee_satoshis`]: crate::util::config::ChannelConfig::force_close_avoidance_max_fee_satoshis
-       /// [`Background`]: crate::chain::chaininterface::ConfirmationTarget::Background
-       /// [`Normal`]: crate::chain::chaininterface::ConfirmationTarget::Normal
+       /// [`NonAnchorChannelFee`]: crate::chain::chaininterface::ConfirmationTarget::NonAnchorChannelFee
        /// [`SendShutdown`]: crate::events::MessageSendEvent::SendShutdown
        pub fn close_channel_with_feerate_and_script(&self, channel_id: &ChannelId, counterparty_node_id: &PublicKey, target_feerate_sats_per_1000_weight: Option<u32>, shutdown_script: Option<ShutdownScript>) -> Result<(), APIError> {
                self.close_channel_internal(channel_id, counterparty_node_id, target_feerate_sats_per_1000_weight, shutdown_script)
        }
 
-       fn finish_close_channel(&self, shutdown_res: ShutdownResult) {
+       fn finish_close_channel(&self, mut shutdown_res: ShutdownResult) {
                debug_assert_ne!(self.per_peer_state.held_by_thread(), LockHeldState::HeldByThread);
                #[cfg(debug_assertions)]
                for (_, peer) in self.per_peer_state.read().unwrap().iter() {
                        debug_assert_ne!(peer.held_by_thread(), LockHeldState::HeldByThread);
                }
 
-               let (monitor_update_option, mut failed_htlcs, unbroadcasted_batch_funding_txid) = shutdown_res;
-               log_debug!(self.logger, "Finishing force-closure of channel with {} HTLCs to fail", failed_htlcs.len());
-               for htlc_source in failed_htlcs.drain(..) {
+               log_debug!(self.logger, "Finishing closure of channel with {} HTLCs to fail", shutdown_res.dropped_outbound_htlcs.len());
+               for htlc_source in shutdown_res.dropped_outbound_htlcs.drain(..) {
                        let (source, payment_hash, counterparty_node_id, channel_id) = htlc_source;
                        let reason = HTLCFailReason::from_failure_code(0x4000 | 8);
                        let receiver = HTLCDestination::NextHopChannel { node_id: Some(counterparty_node_id), channel_id };
                        self.fail_htlc_backwards_internal(&source, &payment_hash, &reason, receiver);
                }
-               if let Some((_, funding_txo, monitor_update)) = monitor_update_option {
+               if let Some((_, funding_txo, monitor_update)) = shutdown_res.monitor_update {
                        // There isn't anything we can do if we get an update failure - we're already
                        // force-closing. The monitor update on the required in-memory copy should broadcast
                        // the latest local state, which is the best we can do anyway. Thus, it is safe to
@@ -2724,7 +2781,7 @@ where
                        let _ = self.chain_monitor.update_channel(funding_txo, &monitor_update);
                }
                let mut shutdown_results = Vec::new();
-               if let Some(txid) = unbroadcasted_batch_funding_txid {
+               if let Some(txid) = shutdown_res.unbroadcasted_batch_funding_txid {
                        let mut funding_batch_states = self.funding_batch_states.lock().unwrap();
                        let affected_channels = funding_batch_states.remove(&txid).into_iter().flatten();
                        let per_peer_state = self.per_peer_state.read().unwrap();
@@ -2866,192 +2923,15 @@ where
                }
        }
 
-       fn construct_fwd_pending_htlc_info(
-               &self, msg: &msgs::UpdateAddHTLC, hop_data: msgs::InboundOnionPayload, hop_hmac: [u8; 32],
-               new_packet_bytes: [u8; onion_utils::ONION_DATA_LEN], shared_secret: [u8; 32],
-               next_packet_pubkey_opt: Option<Result<PublicKey, secp256k1::Error>>
-       ) -> Result<PendingHTLCInfo, InboundOnionErr> {
-               debug_assert!(next_packet_pubkey_opt.is_some());
-               let outgoing_packet = msgs::OnionPacket {
-                       version: 0,
-                       public_key: next_packet_pubkey_opt.unwrap_or(Err(secp256k1::Error::InvalidPublicKey)),
-                       hop_data: new_packet_bytes,
-                       hmac: hop_hmac,
-               };
-
-               let (short_channel_id, amt_to_forward, outgoing_cltv_value) = match hop_data {
-                       msgs::InboundOnionPayload::Forward { short_channel_id, amt_to_forward, outgoing_cltv_value } =>
-                               (short_channel_id, amt_to_forward, outgoing_cltv_value),
-                       msgs::InboundOnionPayload::Receive { .. } | msgs::InboundOnionPayload::BlindedReceive { .. } =>
-                               return Err(InboundOnionErr {
-                                       msg: "Final Node OnionHopData provided for us as an intermediary node",
-                                       err_code: 0x4000 | 22,
-                                       err_data: Vec::new(),
-                               }),
-               };
-
-               Ok(PendingHTLCInfo {
-                       routing: PendingHTLCRouting::Forward {
-                               onion_packet: outgoing_packet,
-                               short_channel_id,
-                       },
-                       payment_hash: msg.payment_hash,
-                       incoming_shared_secret: shared_secret,
-                       incoming_amt_msat: Some(msg.amount_msat),
-                       outgoing_amt_msat: amt_to_forward,
-                       outgoing_cltv_value,
-                       skimmed_fee_msat: None,
-               })
-       }
-
-       fn construct_recv_pending_htlc_info(
-               &self, hop_data: msgs::InboundOnionPayload, shared_secret: [u8; 32], payment_hash: PaymentHash,
-               amt_msat: u64, cltv_expiry: u32, phantom_shared_secret: Option<[u8; 32]>, allow_underpay: bool,
-               counterparty_skimmed_fee_msat: Option<u64>,
-       ) -> Result<PendingHTLCInfo, InboundOnionErr> {
-               let (payment_data, keysend_preimage, custom_tlvs, onion_amt_msat, outgoing_cltv_value, payment_metadata) = match hop_data {
-                       msgs::InboundOnionPayload::Receive {
-                               payment_data, keysend_preimage, custom_tlvs, amt_msat, outgoing_cltv_value, payment_metadata, ..
-                       } =>
-                               (payment_data, keysend_preimage, custom_tlvs, amt_msat, outgoing_cltv_value, payment_metadata),
-                       msgs::InboundOnionPayload::BlindedReceive {
-                               amt_msat, total_msat, outgoing_cltv_value, payment_secret, ..
-                       } => {
-                               let payment_data = msgs::FinalOnionHopData { payment_secret, total_msat };
-                               (Some(payment_data), None, Vec::new(), amt_msat, outgoing_cltv_value, None)
-                       }
-                       msgs::InboundOnionPayload::Forward { .. } => {
-                               return Err(InboundOnionErr {
-                                       err_code: 0x4000|22,
-                                       err_data: Vec::new(),
-                                       msg: "Got non final data with an HMAC of 0",
-                               })
-                       },
-               };
-               // final_incorrect_cltv_expiry
-               if outgoing_cltv_value > cltv_expiry {
-                       return Err(InboundOnionErr {
-                               msg: "Upstream node set CLTV to less than the CLTV set by the sender",
-                               err_code: 18,
-                               err_data: cltv_expiry.to_be_bytes().to_vec()
-                       })
-               }
-               // final_expiry_too_soon
-               // We have to have some headroom to broadcast on chain if we have the preimage, so make sure
-               // we have at least HTLC_FAIL_BACK_BUFFER blocks to go.
-               //
-               // Also, ensure that, in the case of an unknown preimage for the received payment hash, our
-               // payment logic has enough time to fail the HTLC backward before our onchain logic triggers a
-               // channel closure (see HTLC_FAIL_BACK_BUFFER rationale).
-               let current_height: u32 = self.best_block.read().unwrap().height();
-               if cltv_expiry <= current_height + HTLC_FAIL_BACK_BUFFER + 1 {
-                       let mut err_data = Vec::with_capacity(12);
-                       err_data.extend_from_slice(&amt_msat.to_be_bytes());
-                       err_data.extend_from_slice(&current_height.to_be_bytes());
-                       return Err(InboundOnionErr {
-                               err_code: 0x4000 | 15, err_data,
-                               msg: "The final CLTV expiry is too soon to handle",
-                       });
-               }
-               if (!allow_underpay && onion_amt_msat > amt_msat) ||
-                       (allow_underpay && onion_amt_msat >
-                        amt_msat.saturating_add(counterparty_skimmed_fee_msat.unwrap_or(0)))
-               {
-                       return Err(InboundOnionErr {
-                               err_code: 19,
-                               err_data: amt_msat.to_be_bytes().to_vec(),
-                               msg: "Upstream node sent less than we were supposed to receive in payment",
-                       });
-               }
-
-               let routing = if let Some(payment_preimage) = keysend_preimage {
-                       // We need to check that the sender knows the keysend preimage before processing this
-                       // payment further. Otherwise, an intermediary routing hop forwarding non-keysend-HTLC X
-                       // could discover the final destination of X, by probing the adjacent nodes on the route
-                       // with a keysend payment of identical payment hash to X and observing the processing
-                       // time discrepancies due to a hash collision with X.
-                       let hashed_preimage = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
-                       if hashed_preimage != payment_hash {
-                               return Err(InboundOnionErr {
-                                       err_code: 0x4000|22,
-                                       err_data: Vec::new(),
-                                       msg: "Payment preimage didn't match payment hash",
-                               });
-                       }
-                       if !self.default_configuration.accept_mpp_keysend && payment_data.is_some() {
-                               return Err(InboundOnionErr {
-                                       err_code: 0x4000|22,
-                                       err_data: Vec::new(),
-                                       msg: "We don't support MPP keysend payments",
-                               });
-                       }
-                       PendingHTLCRouting::ReceiveKeysend {
-                               payment_data,
-                               payment_preimage,
-                               payment_metadata,
-                               incoming_cltv_expiry: outgoing_cltv_value,
-                               custom_tlvs,
-                       }
-               } else if let Some(data) = payment_data {
-                       PendingHTLCRouting::Receive {
-                               payment_data: data,
-                               payment_metadata,
-                               incoming_cltv_expiry: outgoing_cltv_value,
-                               phantom_shared_secret,
-                               custom_tlvs,
-                       }
-               } else {
-                       return Err(InboundOnionErr {
-                               err_code: 0x4000|0x2000|3,
-                               err_data: Vec::new(),
-                               msg: "We require payment_secrets",
-                       });
-               };
-               Ok(PendingHTLCInfo {
-                       routing,
-                       payment_hash,
-                       incoming_shared_secret: shared_secret,
-                       incoming_amt_msat: Some(amt_msat),
-                       outgoing_amt_msat: onion_amt_msat,
-                       outgoing_cltv_value,
-                       skimmed_fee_msat: counterparty_skimmed_fee_msat,
-               })
-       }
-
        fn decode_update_add_htlc_onion(
                &self, msg: &msgs::UpdateAddHTLC
-       ) -> Result<(onion_utils::Hop, [u8; 32], Option<Result<PublicKey, secp256k1::Error>>), HTLCFailureMsg> {
-               macro_rules! return_malformed_err {
-                       ($msg: expr, $err_code: expr) => {
-                               {
-                                       log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
-                                       return Err(HTLCFailureMsg::Malformed(msgs::UpdateFailMalformedHTLC {
-                                               channel_id: msg.channel_id,
-                                               htlc_id: msg.htlc_id,
-                                               sha256_of_onion: Sha256::hash(&msg.onion_routing_packet.hop_data).into_inner(),
-                                               failure_code: $err_code,
-                                       }));
-                               }
-                       }
-               }
-
-               if let Err(_) = msg.onion_routing_packet.public_key {
-                       return_malformed_err!("invalid ephemeral pubkey", 0x8000 | 0x4000 | 6);
-               }
-
-               let shared_secret = self.node_signer.ecdh(
-                       Recipient::Node, &msg.onion_routing_packet.public_key.unwrap(), None
-               ).unwrap().secret_bytes();
+       ) -> Result<
+               (onion_utils::Hop, [u8; 32], Option<Result<PublicKey, secp256k1::Error>>), HTLCFailureMsg
+       > {
+               let (next_hop, shared_secret, next_packet_details_opt) = decode_incoming_update_add_htlc_onion(
+                       msg, &self.node_signer, &self.logger, &self.secp_ctx
+               )?;
 
-               if msg.onion_routing_packet.version != 0 {
-                       //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
-                       //sha256_of_onion error data packets), or the entire onion_routing_packet. Either way,
-                       //the hash doesn't really serve any purpose - in the case of hashing all data, the
-                       //receiving node would have to brute force to figure out which version was put in the
-                       //packet by the node that send us the message, in the case of hashing the hop_data, the
-                       //node knows the HMAC matched, so they already know what is there...
-                       return_malformed_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4);
-               }
                macro_rules! return_err {
                        ($msg: expr, $err_code: expr, $data: expr) => {
                                {
@@ -3066,36 +2946,12 @@ where
                        }
                }
 
-               let next_hop = match onion_utils::decode_next_payment_hop(
-                       shared_secret, &msg.onion_routing_packet.hop_data[..], msg.onion_routing_packet.hmac,
-                       msg.payment_hash, &self.node_signer
-               ) {
-                       Ok(res) => res,
-                       Err(onion_utils::OnionDecodeErr::Malformed { err_msg, err_code }) => {
-                               return_malformed_err!(err_msg, err_code);
-                       },
-                       Err(onion_utils::OnionDecodeErr::Relay { err_msg, err_code }) => {
-                               return_err!(err_msg, err_code, &[0; 0]);
-                       },
-               };
-               let (outgoing_scid, outgoing_amt_msat, outgoing_cltv_value, next_packet_pk_opt) = match next_hop {
-                       onion_utils::Hop::Forward {
-                               next_hop_data: msgs::InboundOnionPayload::Forward {
-                                       short_channel_id, amt_to_forward, outgoing_cltv_value
-                               }, ..
-                       } => {
-                               let next_packet_pk = onion_utils::next_hop_pubkey(&self.secp_ctx,
-                                       msg.onion_routing_packet.public_key.unwrap(), &shared_secret);
-                               (short_channel_id, amt_to_forward, outgoing_cltv_value, Some(next_packet_pk))
-                       },
-                       // We'll do receive checks in [`Self::construct_pending_htlc_info`] so we have access to the
-                       // inbound channel's state.
-                       onion_utils::Hop::Receive { .. } => return Ok((next_hop, shared_secret, None)),
-                       onion_utils::Hop::Forward { next_hop_data: msgs::InboundOnionPayload::Receive { .. }, .. } |
-                               onion_utils::Hop::Forward { next_hop_data: msgs::InboundOnionPayload::BlindedReceive { .. }, .. } =>
-                       {
-                               return_err!("Final Node OnionHopData provided for us as an intermediary node", 0x4000 | 22, &[0; 0]);
-                       }
+               let NextPacketDetails {
+                       next_packet_pubkey, outgoing_amt_msat, outgoing_scid, outgoing_cltv_value
+               } = match next_packet_details_opt {
+                       Some(next_packet_details) => next_packet_details,
+                       // it is a receive, so no need for outbound checks
+                       None => return Ok((next_hop, shared_secret, None)),
                };
 
                // Perform outbound checks here instead of in [`Self::construct_pending_htlc_info`] because we
@@ -3172,38 +3028,22 @@ where
                                }
                                chan_update_opt
                        } else {
-                               if (msg.cltv_expiry as u64) < (outgoing_cltv_value) as u64 + MIN_CLTV_EXPIRY_DELTA as u64 {
-                                       // We really should set `incorrect_cltv_expiry` here but as we're not
-                                       // forwarding over a real channel we can't generate a channel_update
-                                       // for it. Instead we just return a generic temporary_node_failure.
-                                       break Some((
-                                                       "Forwarding node has tampered with the intended HTLC values or origin node has an obsolete cltv_expiry_delta",
-                                                       0x2000 | 2, None,
-                                       ));
-                               }
                                None
                        };
 
                        let cur_height = self.best_block.read().unwrap().height() + 1;
-                       // Theoretically, channel counterparty shouldn't send us a HTLC expiring now,
-                       // but we want to be robust wrt to counterparty packet sanitization (see
-                       // HTLC_FAIL_BACK_BUFFER rationale).
-                       if msg.cltv_expiry <= cur_height + HTLC_FAIL_BACK_BUFFER as u32 { // expiry_too_soon
-                               break Some(("CLTV expiry is too close", 0x1000 | 14, chan_update_opt));
-                       }
-                       if msg.cltv_expiry > cur_height + CLTV_FAR_FAR_AWAY as u32 { // expiry_too_far
-                               break Some(("CLTV expiry is too far in the future", 21, None));
-                       }
-                       // If the HTLC expires ~now, don't bother trying to forward it to our
-                       // counterparty. They should fail it anyway, but we don't want to bother with
-                       // the round-trips or risk them deciding they definitely want the HTLC and
-                       // force-closing to ensure they get it if we're offline.
-                       // We previously had a much more aggressive check here which tried to ensure
-                       // our counterparty receives an HTLC which has *our* risk threshold met on it,
-                       // but there is no need to do that, and since we're a bit conservative with our
-                       // risk threshold it just results in failing to forward payments.
-                       if (outgoing_cltv_value) as u64 <= (cur_height + LATENCY_GRACE_PERIOD_BLOCKS) as u64 {
-                               break Some(("Outgoing CLTV value is too soon", 0x1000 | 14, chan_update_opt));
+
+                       if let Err((err_msg, code)) = check_incoming_htlc_cltv(
+                               cur_height, outgoing_cltv_value, msg.cltv_expiry
+                       ) {
+                               if code & 0x1000 != 0 && chan_update_opt.is_none() {
+                                       // We really should set `incorrect_cltv_expiry` here but as we're not
+                                       // forwarding over a real channel we can't generate a channel_update
+                                       // for it. Instead we just return a generic temporary_node_failure.
+                                       break Some((err_msg, 0x2000 | 2, None))
+                               }
+                               let chan_update_opt = if code & 0x1000 != 0 { chan_update_opt } else { None };
+                               break Some((err_msg, code, chan_update_opt));
                        }
 
                        break None;
@@ -3233,7 +3073,7 @@ where
                        }
                        return_err!(err, code, &res.0[..]);
                }
-               Ok((next_hop, shared_secret, next_packet_pk_opt))
+               Ok((next_hop, shared_secret, Some(next_packet_pubkey)))
        }
 
        fn construct_pending_htlc_status<'a>(
@@ -3256,8 +3096,10 @@ where
                match decoded_hop {
                        onion_utils::Hop::Receive(next_hop_data) => {
                                // OUR PAYMENT!
-                               match self.construct_recv_pending_htlc_info(next_hop_data, shared_secret, msg.payment_hash,
-                                       msg.amount_msat, msg.cltv_expiry, None, allow_underpay, msg.skimmed_fee_msat)
+                               let current_height: u32 = self.best_block.read().unwrap().height();
+                               match create_recv_pending_htlc_info(next_hop_data, shared_secret, msg.payment_hash,
+                                       msg.amount_msat, msg.cltv_expiry, None, allow_underpay, msg.skimmed_fee_msat,
+                                       current_height, self.default_configuration.accept_mpp_keysend)
                                {
                                        Ok(info) => {
                                                // Note that we could obviously respond immediately with an update_fulfill_htlc
@@ -3270,7 +3112,7 @@ where
                                }
                        },
                        onion_utils::Hop::Forward { next_hop_data, next_hop_hmac, new_packet_bytes } => {
-                               match self.construct_fwd_pending_htlc_info(msg, next_hop_data, next_hop_hmac,
+                               match create_fwd_pending_htlc_info(msg, next_hop_data, next_hop_hmac,
                                        new_packet_bytes, shared_secret, next_packet_pubkey_opt) {
                                        Ok(info) => PendingHTLCStatus::Forward(info),
                                        Err(InboundOnionErr { err_code, err_data, msg }) => return_err!(msg, err_code, &err_data)
@@ -3544,6 +3386,17 @@ where
                self.pending_outbound_payments.test_set_payment_metadata(payment_id, new_payment_metadata);
        }
 
+       pub(super) fn send_payment_for_bolt12_invoice(&self, invoice: &Bolt12Invoice, payment_id: PaymentId) -> Result<(), Bolt12PaymentError> {
+               let best_block_height = self.best_block.read().unwrap().height();
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
+               self.pending_outbound_payments
+                       .send_payment_for_bolt12_invoice(
+                               invoice, payment_id, &self.router, self.list_usable_channels(),
+                               || self.compute_inflight_htlcs(), &self.entropy_source, &self.node_signer,
+                               best_block_height, &self.logger, &self.pending_events,
+                               |args| self.send_payment_along_path(args)
+                       )
+       }
 
        /// Signals that no further attempts for the given payment should occur. Useful if you have a
        /// pending outbound payment with retries remaining, but wish to stop retrying the payment before
@@ -3558,10 +3411,20 @@ where
        /// wait until you receive either a [`Event::PaymentFailed`] or [`Event::PaymentSent`] event to
        /// determine the ultimate status of a payment.
        ///
+       /// # Requested Invoices
+       ///
+       /// In the case of paying a [`Bolt12Invoice`] via [`ChannelManager::pay_for_offer`], abandoning
+       /// the payment prior to receiving the invoice will result in an [`Event::InvoiceRequestFailed`]
+       /// and prevent any attempts at paying it once received. The other events may only be generated
+       /// once the invoice has been received.
+       ///
        /// # Restart Behavior
        ///
        /// If an [`Event::PaymentFailed`] is generated and we restart without first persisting the
-       /// [`ChannelManager`], another [`Event::PaymentFailed`] may be generated.
+       /// [`ChannelManager`], another [`Event::PaymentFailed`] may be generated; likewise for
+       /// [`Event::InvoiceRequestFailed`].
+       ///
+       /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
        pub fn abandon_payment(&self, payment_id: PaymentId) {
                let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                self.pending_outbound_payments.abandon_payment(payment_id, PaymentFailureReason::UserAbandoned, &self.pending_events);
@@ -3848,7 +3711,7 @@ where
        /// Return values are identical to [`Self::funding_transaction_generated`], respective to
        /// each individual channel and transaction output.
        ///
-       /// Do NOT broadcast the funding transaction yourself. This batch funding transcaction
+       /// Do NOT broadcast the funding transaction yourself. This batch funding transaction
        /// will only be broadcast when we have safely received and persisted the counterparty's
        /// signature for each channel.
        ///
@@ -3902,7 +3765,7 @@ where
                                btree_map::Entry::Vacant(vacant) => Some(vacant.insert(Vec::new())),
                        }
                });
-               for &(temporary_channel_id, counterparty_node_id) in temporary_channels.iter() {
+               for &(temporary_channel_id, counterparty_node_id) in temporary_channels {
                        result = result.and_then(|_| self.funding_transaction_generated_intern(
                                temporary_channel_id,
                                counterparty_node_id,
@@ -4275,9 +4138,11 @@ where
                                                                                                };
                                                                                                match next_hop {
                                                                                                        onion_utils::Hop::Receive(hop_data) => {
-                                                                                                               match self.construct_recv_pending_htlc_info(hop_data,
+                                                                                                               let current_height: u32 = self.best_block.read().unwrap().height();
+                                                                                                               match create_recv_pending_htlc_info(hop_data,
                                                                                                                        incoming_shared_secret, payment_hash, outgoing_amt_msat,
-                                                                                                                       outgoing_cltv_value, Some(phantom_shared_secret), false, None)
+                                                                                                                       outgoing_cltv_value, Some(phantom_shared_secret), false, None,
+                                                                                                                       current_height, self.default_configuration.accept_mpp_keysend)
                                                                                                                {
                                                                                                                        Ok(info) => phantom_receives.push((prev_short_channel_id, prev_funding_outpoint, prev_user_channel_id, vec![(info, prev_htlc_id)])),
                                                                                                                        Err(InboundOnionErr { err_code, err_data, msg }) => failed_payment!(msg, err_code, err_data, Some(phantom_shared_secret))
@@ -4759,8 +4624,8 @@ where
                PersistenceNotifierGuard::optionally_notify(self, || {
                        let mut should_persist = NotifyOption::SkipPersistNoEvents;
 
-                       let normal_feerate = self.fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Normal);
-                       let min_mempool_feerate = self.fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::MempoolMinimum);
+                       let non_anchor_feerate = self.fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::NonAnchorChannelFee);
+                       let anchor_feerate = self.fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::AnchorChannelFee);
 
                        let per_peer_state = self.per_peer_state.read().unwrap();
                        for (_cp_id, peer_state_mutex) in per_peer_state.iter() {
@@ -4770,9 +4635,9 @@ where
                                        |(chan_id, phase)| if let ChannelPhase::Funded(chan) = phase { Some((chan_id, chan)) } else { None }
                                ) {
                                        let new_feerate = if chan.context.get_channel_type().supports_anchors_zero_fee_htlc_tx() {
-                                               min_mempool_feerate
+                                               anchor_feerate
                                        } else {
-                                               normal_feerate
+                                               non_anchor_feerate
                                        };
                                        let chan_needs_persist = self.update_channel_fee(chan_id, chan, new_feerate);
                                        if chan_needs_persist == NotifyOption::DoPersist { should_persist = NotifyOption::DoPersist; }
@@ -4796,8 +4661,8 @@ where
        ///  * Force-closing and removing channels which have not completed establishment in a timely manner.
        ///  * Forgetting about stale outbound payments, either those that have already been fulfilled
        ///    or those awaiting an invoice that hasn't been delivered in the necessary amount of time.
-       ///    The latter is determined using the system clock in `std` and the block time minus two
-       ///    hours in `no-std`.
+       ///    The latter is determined using the system clock in `std` and the highest seen block time
+       ///    minus two hours in `no-std`.
        ///
        /// Note that this may cause reentrancy through [`chain::Watch::update_channel`] calls or feerate
        /// estimate fetches.
@@ -4808,8 +4673,8 @@ where
                PersistenceNotifierGuard::optionally_notify(self, || {
                        let mut should_persist = NotifyOption::SkipPersistNoEvents;
 
-                       let normal_feerate = self.fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Normal);
-                       let min_mempool_feerate = self.fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::MempoolMinimum);
+                       let non_anchor_feerate = self.fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::NonAnchorChannelFee);
+                       let anchor_feerate = self.fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::AnchorChannelFee);
 
                        let mut handle_errors: Vec<(Result<(), _>, _)> = Vec::new();
                        let mut timed_out_mpp_htlcs = Vec::new();
@@ -4856,9 +4721,9 @@ where
                                                match phase {
                                                        ChannelPhase::Funded(chan) => {
                                                                let new_feerate = if chan.context.get_channel_type().supports_anchors_zero_fee_htlc_tx() {
-                                                                       min_mempool_feerate
+                                                                       anchor_feerate
                                                                } else {
-                                                                       normal_feerate
+                                                                       non_anchor_feerate
                                                                };
                                                                let chan_needs_persist = self.update_channel_fee(chan_id, chan, new_feerate);
                                                                if chan_needs_persist == NotifyOption::DoPersist { should_persist = NotifyOption::DoPersist; }
@@ -5377,8 +5242,11 @@ where
                        for htlc in sources.drain(..) {
                                if let Err((pk, err)) = self.claim_funds_from_hop(
                                        htlc.prev_hop, payment_preimage,
-                                       |_| Some(MonitorUpdateCompletionAction::PaymentClaimed { payment_hash }))
-                               {
+                                       |_, definitely_duplicate| {
+                                               debug_assert!(!definitely_duplicate, "We shouldn't claim duplicatively from a payment");
+                                               Some(MonitorUpdateCompletionAction::PaymentClaimed { payment_hash })
+                                       }
+                               ) {
                                        if let msgs::ErrorAction::IgnoreError = err.err.action {
                                                // We got a temporary failure updating monitor, but will claim the
                                                // HTLC when the monitor updating is restored (or on chain).
@@ -5406,7 +5274,7 @@ where
                }
        }
 
-       fn claim_funds_from_hop<ComplFunc: FnOnce(Option<u64>) -> Option<MonitorUpdateCompletionAction>>(&self,
+       fn claim_funds_from_hop<ComplFunc: FnOnce(Option<u64>, bool) -> Option<MonitorUpdateCompletionAction>>(&self,
                prev_hop: HTLCPreviousHopData, payment_preimage: PaymentPreimage, completion_action: ComplFunc)
        -> Result<(), (PublicKey, MsgHandleErrInternal)> {
                //TODO: Delay the claimed_funds relaying just like we do outbound relay!
@@ -5416,6 +5284,11 @@ where
                // `BackgroundEvent`s.
                let during_init = !self.background_events_processed_since_startup.load(Ordering::Acquire);
 
+               // As we may call handle_monitor_update_completion_actions in rather rare cases, check that
+               // the required mutexes are not held before we start.
+               debug_assert_ne!(self.pending_events.held_by_thread(), LockHeldState::HeldByThread);
+               debug_assert_ne!(self.claimable_payments.held_by_thread(), LockHeldState::HeldByThread);
+
                {
                        let per_peer_state = self.per_peer_state.read().unwrap();
                        let chan_id = prev_hop.outpoint.to_channel_id();
@@ -5437,25 +5310,70 @@ where
                                                let counterparty_node_id = chan.context.get_counterparty_node_id();
                                                let fulfill_res = chan.get_update_fulfill_htlc_and_commit(prev_hop.htlc_id, payment_preimage, &self.logger);
 
-                                               if let UpdateFulfillCommitFetch::NewClaim { htlc_value_msat, monitor_update } = fulfill_res {
-                                                       if let Some(action) = completion_action(Some(htlc_value_msat)) {
-                                                               log_trace!(self.logger, "Tracking monitor update completion action for channel {}: {:?}",
-                                                                       chan_id, action);
-                                                               peer_state.monitor_update_blocked_actions.entry(chan_id).or_insert(Vec::new()).push(action);
+                                               match fulfill_res {
+                                                       UpdateFulfillCommitFetch::NewClaim { htlc_value_msat, monitor_update } => {
+                                                               if let Some(action) = completion_action(Some(htlc_value_msat), false) {
+                                                                       log_trace!(self.logger, "Tracking monitor update completion action for channel {}: {:?}",
+                                                                               chan_id, action);
+                                                                       peer_state.monitor_update_blocked_actions.entry(chan_id).or_insert(Vec::new()).push(action);
+                                                               }
+                                                               if !during_init {
+                                                                       handle_new_monitor_update!(self, prev_hop.outpoint, monitor_update, peer_state_lock,
+                                                                               peer_state, per_peer_state, chan);
+                                                               } else {
+                                                                       // If we're running during init we cannot update a monitor directly -
+                                                                       // they probably haven't actually been loaded yet. Instead, push the
+                                                                       // monitor update as a background event.
+                                                                       self.pending_background_events.lock().unwrap().push(
+                                                                               BackgroundEvent::MonitorUpdateRegeneratedOnStartup {
+                                                                                       counterparty_node_id,
+                                                                                       funding_txo: prev_hop.outpoint,
+                                                                                       update: monitor_update.clone(),
+                                                                               });
+                                                               }
                                                        }
-                                                       if !during_init {
-                                                               handle_new_monitor_update!(self, prev_hop.outpoint, monitor_update, peer_state_lock,
-                                                                       peer_state, per_peer_state, chan);
-                                                       } else {
-                                                               // If we're running during init we cannot update a monitor directly -
-                                                               // they probably haven't actually been loaded yet. Instead, push the
-                                                               // monitor update as a background event.
-                                                               self.pending_background_events.lock().unwrap().push(
-                                                                       BackgroundEvent::MonitorUpdateRegeneratedOnStartup {
-                                                                               counterparty_node_id,
-                                                                               funding_txo: prev_hop.outpoint,
-                                                                               update: monitor_update.clone(),
-                                                                       });
+                                                       UpdateFulfillCommitFetch::DuplicateClaim {} => {
+                                                               let action = if let Some(action) = completion_action(None, true) {
+                                                                       action
+                                                               } else {
+                                                                       return Ok(());
+                                                               };
+                                                               mem::drop(peer_state_lock);
+
+                                                               log_trace!(self.logger, "Completing monitor update completion action for channel {} as claim was redundant: {:?}",
+                                                                       chan_id, action);
+                                                               let (node_id, funding_outpoint, blocker) =
+                                                               if let MonitorUpdateCompletionAction::FreeOtherChannelImmediately {
+                                                                       downstream_counterparty_node_id: node_id,
+                                                                       downstream_funding_outpoint: funding_outpoint,
+                                                                       blocking_action: blocker,
+                                                               } = action {
+                                                                       (node_id, funding_outpoint, blocker)
+                                                               } else {
+                                                                       debug_assert!(false,
+                                                                               "Duplicate claims should always free another channel immediately");
+                                                                       return Ok(());
+                                                               };
+                                                               if let Some(peer_state_mtx) = per_peer_state.get(&node_id) {
+                                                                       let mut peer_state = peer_state_mtx.lock().unwrap();
+                                                                       if let Some(blockers) = peer_state
+                                                                               .actions_blocking_raa_monitor_updates
+                                                                               .get_mut(&funding_outpoint.to_channel_id())
+                                                                       {
+                                                                               let mut found_blocker = false;
+                                                                               blockers.retain(|iter| {
+                                                                                       // Note that we could actually be blocked, in
+                                                                                       // which case we need to only remove the one
+                                                                                       // blocker which was added duplicatively.
+                                                                                       let first_blocker = !found_blocker;
+                                                                                       if *iter == blocker { found_blocker = true; }
+                                                                                       *iter != blocker || !first_blocker
+                                                                               });
+                                                                               debug_assert!(found_blocker);
+                                                                       }
+                                                               } else {
+                                                                       debug_assert!(false);
+                                                               }
                                                        }
                                                }
                                        }
@@ -5503,7 +5421,7 @@ where
                // `ChannelMonitor` we've provided the above update to. Instead, note that `Event`s are
                // generally always allowed to be duplicative (and it's specifically noted in
                // `PaymentForwarded`).
-               self.handle_monitor_update_completion_actions(completion_action(None));
+               self.handle_monitor_update_completion_actions(completion_action(None, false));
                Ok(())
        }
 
@@ -5512,7 +5430,7 @@ where
        }
 
        fn claim_funds_internal(&self, source: HTLCSource, payment_preimage: PaymentPreimage,
-               forwarded_htlc_value_msat: Option<u64>, from_onchain: bool,
+               forwarded_htlc_value_msat: Option<u64>, from_onchain: bool, startup_replay: bool,
                next_channel_counterparty_node_id: Option<PublicKey>, next_channel_outpoint: OutPoint
        ) {
                match source {
@@ -5533,13 +5451,84 @@ where
                        HTLCSource::PreviousHopData(hop_data) => {
                                let prev_outpoint = hop_data.outpoint;
                                let completed_blocker = RAAMonitorUpdateBlockingAction::from_prev_hop_data(&hop_data);
+                               #[cfg(debug_assertions)]
+                               let claiming_chan_funding_outpoint = hop_data.outpoint;
                                let res = self.claim_funds_from_hop(hop_data, payment_preimage,
-                                       |htlc_claim_value_msat| {
-                                               if let Some(forwarded_htlc_value) = forwarded_htlc_value_msat {
-                                                       let fee_earned_msat = if let Some(claimed_htlc_value) = htlc_claim_value_msat {
-                                                               Some(claimed_htlc_value - forwarded_htlc_value)
-                                                       } else { None };
+                                       |htlc_claim_value_msat, definitely_duplicate| {
+                                               let chan_to_release =
+                                                       if let Some(node_id) = next_channel_counterparty_node_id {
+                                                               Some((node_id, next_channel_outpoint, completed_blocker))
+                                                       } else {
+                                                               // We can only get `None` here if we are processing a
+                                                               // `ChannelMonitor`-originated event, in which case we
+                                                               // don't care about ensuring we wake the downstream
+                                                               // channel's monitor updating - the channel is already
+                                                               // closed.
+                                                               None
+                                                       };
 
+                                               if definitely_duplicate && startup_replay {
+                                                       // On startup we may get redundant claims which are related to
+                                                       // monitor updates still in flight. In that case, we shouldn't
+                                                       // immediately free, but instead let that monitor update complete
+                                                       // in the background.
+                                                       #[cfg(debug_assertions)] {
+                                                               let background_events = self.pending_background_events.lock().unwrap();
+                                                               // There should be a `BackgroundEvent` pending...
+                                                               assert!(background_events.iter().any(|ev| {
+                                                                       match ev {
+                                                                               // to apply a monitor update that blocked the claiming channel,
+                                                                               BackgroundEvent::MonitorUpdateRegeneratedOnStartup {
+                                                                                       funding_txo, update, ..
+                                                                               } => {
+                                                                                       if *funding_txo == claiming_chan_funding_outpoint {
+                                                                                               assert!(update.updates.iter().any(|upd|
+                                                                                                       if let ChannelMonitorUpdateStep::PaymentPreimage {
+                                                                                                               payment_preimage: update_preimage
+                                                                                                       } = upd {
+                                                                                                               payment_preimage == *update_preimage
+                                                                                                       } else { false }
+                                                                                               ), "{:?}", update);
+                                                                                               true
+                                                                                       } else { false }
+                                                                               },
+                                                                               // or the channel we'd unblock is already closed,
+                                                                               BackgroundEvent::ClosedMonitorUpdateRegeneratedOnStartup(
+                                                                                       (funding_txo, monitor_update)
+                                                                               ) => {
+                                                                                       if *funding_txo == next_channel_outpoint {
+                                                                                               assert_eq!(monitor_update.updates.len(), 1);
+                                                                                               assert!(matches!(
+                                                                                                       monitor_update.updates[0],
+                                                                                                       ChannelMonitorUpdateStep::ChannelForceClosed { .. }
+                                                                                               ));
+                                                                                               true
+                                                                                       } else { false }
+                                                                               },
+                                                                               // or the monitor update has completed and will unblock
+                                                                               // immediately once we get going.
+                                                                               BackgroundEvent::MonitorUpdatesComplete {
+                                                                                       channel_id, ..
+                                                                               } =>
+                                                                                       *channel_id == claiming_chan_funding_outpoint.to_channel_id(),
+                                                                       }
+                                                               }), "{:?}", *background_events);
+                                                       }
+                                                       None
+                                               } else if definitely_duplicate {
+                                                       if let Some(other_chan) = chan_to_release {
+                                                               Some(MonitorUpdateCompletionAction::FreeOtherChannelImmediately {
+                                                                       downstream_counterparty_node_id: other_chan.0,
+                                                                       downstream_funding_outpoint: other_chan.1,
+                                                                       blocking_action: other_chan.2,
+                                                               })
+                                                       } else { None }
+                                               } else {
+                                                       let fee_earned_msat = if let Some(forwarded_htlc_value) = forwarded_htlc_value_msat {
+                                                               if let Some(claimed_htlc_value) = htlc_claim_value_msat {
+                                                                       Some(claimed_htlc_value - forwarded_htlc_value)
+                                                               } else { None }
+                                                       } else { None };
                                                        Some(MonitorUpdateCompletionAction::EmitEventAndFreeOtherChannel {
                                                                event: events::Event::PaymentForwarded {
                                                                        fee_earned_msat,
@@ -5548,19 +5537,9 @@ where
                                                                        next_channel_id: Some(next_channel_outpoint.to_channel_id()),
                                                                        outbound_amount_forwarded_msat: forwarded_htlc_value_msat,
                                                                },
-                                                               downstream_counterparty_and_funding_outpoint:
-                                                                       if let Some(node_id) = next_channel_counterparty_node_id {
-                                                                               Some((node_id, next_channel_outpoint, completed_blocker))
-                                                                       } else {
-                                                                               // We can only get `None` here if we are processing a
-                                                                               // `ChannelMonitor`-originated event, in which case we
-                                                                               // don't care about ensuring we wake the downstream
-                                                                               // channel's monitor updating - the channel is already
-                                                                               // closed.
-                                                                               None
-                                                                       },
+                                                               downstream_counterparty_and_funding_outpoint: chan_to_release,
                                                        })
-                                               } else { None }
+                                               }
                                        });
                                if let Err((pk, err)) = res {
                                        let result: Result<(), _> = Err(err);
@@ -5576,6 +5555,10 @@ where
        }
 
        fn handle_monitor_update_completion_actions<I: IntoIterator<Item=MonitorUpdateCompletionAction>>(&self, actions: I) {
+               debug_assert_ne!(self.pending_events.held_by_thread(), LockHeldState::HeldByThread);
+               debug_assert_ne!(self.claimable_payments.held_by_thread(), LockHeldState::HeldByThread);
+               debug_assert_ne!(self.per_peer_state.held_by_thread(), LockHeldState::HeldByThread);
+
                for action in actions.into_iter() {
                        match action {
                                MonitorUpdateCompletionAction::PaymentClaimed { payment_hash } => {
@@ -5605,6 +5588,15 @@ where
                                                self.handle_monitor_update_release(node_id, funding_outpoint, Some(blocker));
                                        }
                                },
+                               MonitorUpdateCompletionAction::FreeOtherChannelImmediately {
+                                       downstream_counterparty_node_id, downstream_funding_outpoint, blocking_action,
+                               } => {
+                                       self.handle_monitor_update_release(
+                                               downstream_counterparty_node_id,
+                                               downstream_funding_outpoint,
+                                               Some(blocking_action),
+                                       );
+                               },
                        }
                }
        }
@@ -6267,22 +6259,20 @@ where
        }
 
        fn internal_closing_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::ClosingSigned) -> Result<(), MsgHandleErrInternal> {
-               let mut shutdown_result = None;
-               let unbroadcasted_batch_funding_txid;
                let per_peer_state = self.per_peer_state.read().unwrap();
                let peer_state_mutex = per_peer_state.get(counterparty_node_id)
                        .ok_or_else(|| {
                                debug_assert!(false);
                                MsgHandleErrInternal::send_err_msg_no_close(format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id), msg.channel_id)
                        })?;
-               let (tx, chan_option) = {
+               let (tx, chan_option, shutdown_result) = {
                        let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                        let peer_state = &mut *peer_state_lock;
                        match peer_state.channel_by_id.entry(msg.channel_id.clone()) {
                                hash_map::Entry::Occupied(mut chan_phase_entry) => {
                                        if let ChannelPhase::Funded(chan) = chan_phase_entry.get_mut() {
-                                               unbroadcasted_batch_funding_txid = chan.context.unbroadcasted_batch_funding_txid();
-                                               let (closing_signed, tx) = try_chan_phase_entry!(self, chan.closing_signed(&self.fee_estimator, &msg), chan_phase_entry);
+                                               let (closing_signed, tx, shutdown_result) = try_chan_phase_entry!(self, chan.closing_signed(&self.fee_estimator, &msg), chan_phase_entry);
+                                               debug_assert_eq!(shutdown_result.is_some(), chan.is_shutdown());
                                                if let Some(msg) = closing_signed {
                                                        peer_state.pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
                                                                node_id: counterparty_node_id.clone(),
@@ -6295,8 +6285,8 @@ where
                                                        // also implies there are no pending HTLCs left on the channel, so we can
                                                        // fully delete it from tracking (the channel monitor is still around to
                                                        // watch for old state broadcasts)!
-                                                       (tx, Some(remove_channel_phase!(self, chan_phase_entry)))
-                                               } else { (tx, None) }
+                                                       (tx, Some(remove_channel_phase!(self, chan_phase_entry)), shutdown_result)
+                                               } else { (tx, None, shutdown_result) }
                                        } else {
                                                return try_chan_phase_entry!(self, Err(ChannelError::Close(
                                                        "Got a closing_signed message for an unfunded channel!".into())), chan_phase_entry);
@@ -6318,7 +6308,6 @@ where
                                });
                        }
                        self.issue_channel_close_events(&chan.context, ClosureReason::CooperativeClosure);
-                       shutdown_result = Some((None, Vec::new(), unbroadcasted_batch_funding_txid));
                }
                mem::drop(per_peer_state);
                if let Some(shutdown_result) = shutdown_result {
@@ -6407,6 +6396,9 @@ where
                                        if let ChannelPhase::Funded(chan) = chan_phase_entry.get_mut() {
                                                let res = try_chan_phase_entry!(self, chan.update_fulfill_htlc(&msg), chan_phase_entry);
                                                if let HTLCSource::PreviousHopData(prev_hop) = &res.0 {
+                                                       log_trace!(self.logger,
+                                                               "Holding the next revoke_and_ack from {} until the preimage is durably persisted in the inbound edge's ChannelMonitor",
+                                                               msg.channel_id);
                                                        peer_state.actions_blocking_raa_monitor_updates.entry(msg.channel_id)
                                                                .or_insert_with(Vec::new)
                                                                .push(RAAMonitorUpdateBlockingAction::from_prev_hop_data(&prev_hop));
@@ -6427,7 +6419,7 @@ where
                                hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close(format!("Got a message for a channel from the wrong node! No such channel for the passed counterparty_node_id {}", counterparty_node_id), msg.channel_id))
                        }
                };
-               self.claim_funds_internal(htlc_source, msg.payment_preimage.clone(), Some(forwarded_htlc_value), false, Some(*counterparty_node_id), funding_txo);
+               self.claim_funds_internal(htlc_source, msg.payment_preimage.clone(), Some(forwarded_htlc_value), false, false, Some(*counterparty_node_id), funding_txo);
                Ok(())
        }
 
@@ -6915,7 +6907,7 @@ where
                                        MonitorEvent::HTLCEvent(htlc_update) => {
                                                if let Some(preimage) = htlc_update.payment_preimage {
                                                        log_trace!(self.logger, "Claiming HTLC with preimage {} from our monitor", preimage);
-                                                       self.claim_funds_internal(htlc_update.source, preimage, htlc_update.htlc_value_satoshis.map(|v| v * 1000), true, counterparty_node_id, funding_outpoint);
+                                                       self.claim_funds_internal(htlc_update.source, preimage, htlc_update.htlc_value_satoshis.map(|v| v * 1000), true, false, counterparty_node_id, funding_outpoint);
                                                } else {
                                                        log_trace!(self.logger, "Failing HTLC with hash {} from our monitor", &htlc_update.payment_hash);
                                                        let receiver = HTLCDestination::NextHopChannel { node_id: counterparty_node_id, channel_id: funding_outpoint.to_channel_id() };
@@ -7048,15 +7040,18 @@ where
                                peer_state.channel_by_id.retain(|channel_id, phase| {
                                        match phase {
                                                ChannelPhase::Funded(chan) => {
-                                                       let unbroadcasted_batch_funding_txid = chan.context.unbroadcasted_batch_funding_txid();
                                                        match chan.maybe_propose_closing_signed(&self.fee_estimator, &self.logger) {
-                                                               Ok((msg_opt, tx_opt)) => {
+                                                               Ok((msg_opt, tx_opt, shutdown_result_opt)) => {
                                                                        if let Some(msg) = msg_opt {
                                                                                has_update = true;
                                                                                pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
                                                                                        node_id: chan.context.get_counterparty_node_id(), msg,
                                                                                });
                                                                        }
+                                                                       debug_assert_eq!(shutdown_result_opt.is_some(), chan.is_shutdown());
+                                                                       if let Some(shutdown_result) = shutdown_result_opt {
+                                                                               shutdown_results.push(shutdown_result);
+                                                                       }
                                                                        if let Some(tx) = tx_opt {
                                                                                // We're done with this channel. We got a closing_signed and sent back
                                                                                // a closing_signed with a closing transaction to broadcast.
@@ -7071,7 +7066,6 @@ where
                                                                                log_info!(self.logger, "Broadcasting {}", log_tx!(tx));
                                                                                self.tx_broadcaster.broadcast_transactions(&[&tx]);
                                                                                update_maps_on_chan_removal!(self, &chan.context);
-                                                                               shutdown_results.push((None, Vec::new(), unbroadcasted_batch_funding_txid));
                                                                                false
                                                                        } else { true }
                                                                },
@@ -7112,7 +7106,7 @@ where
                        // Channel::force_shutdown tries to make us do) as we may still be in initialization,
                        // so we track the update internally and handle it when the user next calls
                        // timer_tick_occurred, guaranteeing we're running normally.
-                       if let Some((counterparty_node_id, funding_txo, update)) = failure.0.take() {
+                       if let Some((counterparty_node_id, funding_txo, update)) = failure.monitor_update.take() {
                                assert_eq!(update.updates.len(), 1);
                                if let ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } = update.updates[0] {
                                        assert!(should_broadcast);
@@ -7130,6 +7124,20 @@ where
        /// [`ChannelManager`] when handling [`InvoiceRequest`] messages for the offer. The offer will
        /// not have an expiration unless otherwise set on the builder.
        ///
+       /// # 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`].
+       ///
+       /// # Limitations
+       ///
+       /// Requires a direct connection to the introduction node in the responding [`InvoiceRequest`]'s
+       /// reply path.
+       ///
+       /// 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(
@@ -7139,21 +7147,55 @@ 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();
 
-               // TODO: Set blinded paths
                OfferBuilder::deriving_signing_pubkey(description, node_id, expanded_key, entropy, secp_ctx)
                        .chain_hash(self.chain_hash)
+                       .path(path)
        }
 
        /// Creates a [`RefundBuilder`] such that the [`Refund`] it builds is recognized by the
-       /// [`ChannelManager`] when handling [`Bolt12Invoice`] messages for the refund. The builder will
-       /// have the provided expiration set. Any changes to the expiration on the returned builder will
-       /// not be honored by [`ChannelManager`].
+       /// [`ChannelManager`] when handling [`Bolt12Invoice`] messages for the refund.
+       ///
+       /// # Payment
        ///
        /// The provided `payment_id` is used to ensure that only one invoice is paid for the refund.
+       /// See [Avoiding Duplicate Payments] for other requirements once the payment has been sent.
+       ///
+       /// The builder will have the provided expiration set. Any changes to the expiration on the
+       /// returned builder will not be honored by [`ChannelManager`]. For `no-std`, the highest seen
+       /// block time minus two hours is used for the current time when determining if the refund has
+       /// expired.
+       ///
+       /// To revoke the refund, use [`ChannelManager::abandon_payment`] prior to receiving the
+       /// invoice. If abandoned, or an invoice isn't received before expiration, the payment will fail
+       /// with an [`Event::InvoiceRequestFailed`].
+       ///
+       /// If `max_total_routing_fee_msat` is not specified, The default from
+       /// [`RouteParameters::from_payment_params_and_value`] is applied.
+       ///
+       /// # 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`].
+       ///
+       /// # Limitations
+       ///
+       /// Requires a direct connection to an introduction node in the responding
+       /// [`Bolt12Invoice::payment_paths`].
+       ///
+       /// # Errors
+       ///
+       /// Errors if a duplicate `payment_id` is provided given the caveats in the aforementioned link
+       /// or if `amount_msats` is invalid.
+       ///
+       /// 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
        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>
@@ -7162,23 +7204,204 @@ 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();
 
-               // TODO: Set blinded paths
                let builder = RefundBuilder::deriving_payer_id(
                        description, node_id, expanded_key, entropy, secp_ctx, amount_msats, payment_id
                )?
                        .chain_hash(self.chain_hash)
-                       .absolute_expiry(absolute_expiry);
+                       .absolute_expiry(absolute_expiry)
+                       .path(path);
 
+               let expiration = StaleExpiration::AbsoluteTimeout(absolute_expiry);
                self.pending_outbound_payments
                        .add_new_awaiting_invoice(
-                               payment_id, absolute_expiry, retry_strategy, max_total_routing_fee_msat,
+                               payment_id, expiration, retry_strategy, max_total_routing_fee_msat,
                        )
                        .map_err(|_| Bolt12SemanticError::DuplicatePaymentId)?;
 
                Ok(builder)
        }
 
+       /// Pays for an [`Offer`] using the given parameters by creating an [`InvoiceRequest`] and
+       /// enqueuing it to be sent via an onion message. [`ChannelManager`] will pay the actual
+       /// [`Bolt12Invoice`] once it is received.
+       ///
+       /// Uses [`InvoiceRequestBuilder`] such that the [`InvoiceRequest`] it builds is recognized by
+       /// the [`ChannelManager`] when handling a [`Bolt12Invoice`] message in response to the request.
+       /// The optional parameters are used in the builder, if `Some`:
+       /// - `quantity` for [`InvoiceRequest::quantity`] which must be set if
+       ///   [`Offer::expects_quantity`] is `true`.
+       /// - `amount_msats` if overpaying what is required for the given `quantity` is desired, and
+       /// - `payer_note` for [`InvoiceRequest::payer_note`].
+       ///
+       /// If `max_total_routing_fee_msat` is not specified, The default from
+       /// [`RouteParameters::from_payment_params_and_value`] is applied.
+       ///
+       /// # Payment
+       ///
+       /// The provided `payment_id` is used to ensure that only one invoice is paid for the request
+       /// when received. See [Avoiding Duplicate Payments] for other requirements once the payment has
+       /// been sent.
+       ///
+       /// To revoke the request, use [`ChannelManager::abandon_payment`] prior to receiving the
+       /// invoice. If abandoned, or an invoice isn't received in a reasonable amount of time, the
+       /// payment will fail with an [`Event::InvoiceRequestFailed`].
+       ///
+       /// # Privacy
+       ///
+       /// Uses a one-hop [`BlindedPath`] for the reply path 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`].
+       ///
+       /// # Limitations
+       ///
+       /// Requires a direct connection to an introduction node in [`Offer::paths`] or to
+       /// [`Offer::signing_pubkey`], if empty. A similar restriction applies to the responding
+       /// [`Bolt12Invoice::payment_paths`].
+       ///
+       /// # 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.
+       ///
+       /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
+       /// [`InvoiceRequest::quantity`]: crate::offers::invoice_request::InvoiceRequest::quantity
+       /// [`InvoiceRequest::payer_note`]: crate::offers::invoice_request::InvoiceRequest::payer_note
+       /// [`InvoiceRequestBuilder`]: crate::offers::invoice_request::InvoiceRequestBuilder
+       /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
+       /// [`Bolt12Invoice::payment_paths`]: crate::offers::invoice::Bolt12Invoice::payment_paths
+       /// [Avoiding Duplicate Payments]: #avoiding-duplicate-payments
+       pub fn pay_for_offer(
+               &self, offer: &Offer, quantity: Option<u64>, amount_msats: Option<u64>,
+               payer_note: Option<String>, payment_id: PaymentId, retry_strategy: Retry,
+               max_total_routing_fee_msat: Option<u64>
+       ) -> Result<(), Bolt12SemanticError> {
+               let expanded_key = &self.inbound_payment_key;
+               let entropy = &*self.entropy_source;
+               let secp_ctx = &self.secp_ctx;
+
+               let builder = offer
+                       .request_invoice_deriving_payer_id(expanded_key, entropy, secp_ctx, payment_id)?
+                       .chain_hash(self.chain_hash)?;
+               let builder = match quantity {
+                       None => builder,
+                       Some(quantity) => builder.quantity(quantity)?,
+               };
+               let builder = match amount_msats {
+                       None => builder,
+                       Some(amount_msats) => builder.amount_msats(amount_msats)?,
+               };
+               let builder = match payer_note {
+                       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 expiration = StaleExpiration::TimerTicks(1);
+               self.pending_outbound_payments
+                       .add_new_awaiting_invoice(
+                               payment_id, expiration, retry_strategy, max_total_routing_fee_msat
+                       )
+                       .map_err(|_| Bolt12SemanticError::DuplicatePaymentId)?;
+
+               let mut pending_offers_messages = self.pending_offers_messages.lock().unwrap();
+               if offer.paths().is_empty() {
+                       let message = new_pending_onion_message(
+                               OffersMessage::InvoiceRequest(invoice_request),
+                               Destination::Node(offer.signing_pubkey()),
+                               Some(reply_path),
+                       );
+                       pending_offers_messages.push(message);
+               } else {
+                       // Send as many invoice requests as there are paths in the offer (with an upper bound).
+                       // Using only one path could result in a failure if the path no longer exists. But only
+                       // one invoice for a given payment id will be paid, even if more than one is received.
+                       const REQUEST_LIMIT: usize = 10;
+                       for path in offer.paths().into_iter().take(REQUEST_LIMIT) {
+                               let message = new_pending_onion_message(
+                                       OffersMessage::InvoiceRequest(invoice_request.clone()),
+                                       Destination::BlindedPath(path.clone()),
+                                       Some(reply_path.clone()),
+                               );
+                               pending_offers_messages.push(message);
+                       }
+               }
+
+               Ok(())
+       }
+
+       /// Creates a [`Bolt12Invoice`] for a [`Refund`] and enqueues it to be sent via an onion
+       /// message.
+       ///
+       /// The resulting invoice uses a [`PaymentHash`] recognized by the [`ChannelManager`] and a
+       /// [`BlindedPath`] containing the [`PaymentSecret`] needed to reconstruct the corresponding
+       /// [`PaymentPreimage`].
+       ///
+       /// # Limitations
+       ///
+       /// Requires a direct connection to an introduction node in [`Refund::paths`] or to
+       /// [`Refund::payer_id`], if empty. This request is best effort; an invoice will be sent to each
+       /// node meeting the aforementioned criteria, but there's no guarantee that they will be
+       /// received and no retries will be made.
+       ///
+       /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
+       pub fn request_refund_payment(&self, refund: &Refund) -> Result<(), Bolt12SemanticError> {
+               let expanded_key = &self.inbound_payment_key;
+               let entropy = &*self.entropy_source;
+               let secp_ctx = &self.secp_ctx;
+
+               let amount_msats = refund.amount_msats();
+               let relative_expiry = DEFAULT_RELATIVE_EXPIRY.as_secs() as u32;
+
+               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),
+                               ];
+                               #[cfg(not(feature = "no-std"))]
+                               let builder = refund.respond_using_derived_keys(
+                                       payment_paths, payment_hash, expanded_key, entropy
+                               )?;
+                               #[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 = refund.respond_using_derived_keys_no_std(
+                                       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 mut pending_offers_messages = self.pending_offers_messages.lock().unwrap();
+                               if refund.paths().is_empty() {
+                                       let message = new_pending_onion_message(
+                                               OffersMessage::Invoice(invoice),
+                                               Destination::Node(refund.payer_id()),
+                                               Some(reply_path),
+                                       );
+                                       pending_offers_messages.push(message);
+                               } else {
+                                       for path in refund.paths() {
+                                               let message = new_pending_onion_message(
+                                                       OffersMessage::Invoice(invoice.clone()),
+                                                       Destination::BlindedPath(path.clone()),
+                                                       Some(reply_path.clone()),
+                                               );
+                                               pending_offers_messages.push(message);
+                                       }
+                               }
+
+                               Ok(())
+                       },
+                       Err(()) => Err(Bolt12SemanticError::InvalidAmount),
+               }
+       }
+
        /// Gets a payment secret and payment hash for use in an invoice given to a third party wishing
        /// to pay us.
        ///
@@ -7279,6 +7502,37 @@ 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 {
+               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()
+       }
+
+       /// 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) {
+               let entropy_source = self.entropy_source.deref();
+               let secp_ctx = &self.secp_ctx;
+
+               let payee_node_id = self.get_our_node_id();
+               let max_cltv_expiry = self.best_block.read().unwrap().height() + LATENCY_GRACE_PERIOD_BLOCKS;
+               let payee_tlvs = ReceiveTlvs {
+                       payment_secret,
+                       payment_constraints: PaymentConstraints {
+                               max_cltv_expiry,
+                               htlc_minimum_msat: 1,
+                       },
+               };
+               // TODO: Err for overflow?
+               BlindedPath::one_hop_for_payment(
+                       payee_node_id, payee_tlvs, entropy_source, secp_ctx
+               ).unwrap()
+       }
+
        /// Gets a fake short channel id for use in receiving [phantom node payments]. These fake scids
        /// are used when constructing the phantom invoice's route hints.
        ///
@@ -7459,6 +7713,346 @@ where
        }
 }
 
+fn create_fwd_pending_htlc_info(
+       msg: &msgs::UpdateAddHTLC, hop_data: msgs::InboundOnionPayload, hop_hmac: [u8; 32],
+       new_packet_bytes: [u8; onion_utils::ONION_DATA_LEN], shared_secret: [u8; 32],
+       next_packet_pubkey_opt: Option<Result<PublicKey, secp256k1::Error>>
+) -> Result<PendingHTLCInfo, InboundOnionErr> {
+       debug_assert!(next_packet_pubkey_opt.is_some());
+       let outgoing_packet = msgs::OnionPacket {
+               version: 0,
+               public_key: next_packet_pubkey_opt.unwrap_or(Err(secp256k1::Error::InvalidPublicKey)),
+               hop_data: new_packet_bytes,
+               hmac: hop_hmac,
+       };
+
+       let (short_channel_id, amt_to_forward, outgoing_cltv_value) = match hop_data {
+               msgs::InboundOnionPayload::Forward { short_channel_id, amt_to_forward, outgoing_cltv_value } =>
+                       (short_channel_id, amt_to_forward, outgoing_cltv_value),
+               msgs::InboundOnionPayload::Receive { .. } | msgs::InboundOnionPayload::BlindedReceive { .. } =>
+                       return Err(InboundOnionErr {
+                               msg: "Final Node OnionHopData provided for us as an intermediary node",
+                               err_code: 0x4000 | 22,
+                               err_data: Vec::new(),
+                       }),
+       };
+
+       Ok(PendingHTLCInfo {
+               routing: PendingHTLCRouting::Forward {
+                       onion_packet: outgoing_packet,
+                       short_channel_id,
+               },
+               payment_hash: msg.payment_hash,
+               incoming_shared_secret: shared_secret,
+               incoming_amt_msat: Some(msg.amount_msat),
+               outgoing_amt_msat: amt_to_forward,
+               outgoing_cltv_value,
+               skimmed_fee_msat: None,
+       })
+}
+
+fn create_recv_pending_htlc_info(
+       hop_data: msgs::InboundOnionPayload, shared_secret: [u8; 32], payment_hash: PaymentHash,
+       amt_msat: u64, cltv_expiry: u32, phantom_shared_secret: Option<[u8; 32]>, allow_underpay: bool,
+       counterparty_skimmed_fee_msat: Option<u64>, current_height: u32, accept_mpp_keysend: bool,
+) -> Result<PendingHTLCInfo, InboundOnionErr> {
+       let (payment_data, keysend_preimage, custom_tlvs, onion_amt_msat, outgoing_cltv_value, payment_metadata) = match hop_data {
+               msgs::InboundOnionPayload::Receive {
+                       payment_data, keysend_preimage, custom_tlvs, amt_msat, outgoing_cltv_value, payment_metadata, ..
+               } =>
+                       (payment_data, keysend_preimage, custom_tlvs, amt_msat, outgoing_cltv_value, payment_metadata),
+               msgs::InboundOnionPayload::BlindedReceive {
+                       amt_msat, total_msat, outgoing_cltv_value, payment_secret, ..
+               } => {
+                       let payment_data = msgs::FinalOnionHopData { payment_secret, total_msat };
+                       (Some(payment_data), None, Vec::new(), amt_msat, outgoing_cltv_value, None)
+               }
+               msgs::InboundOnionPayload::Forward { .. } => {
+                       return Err(InboundOnionErr {
+                               err_code: 0x4000|22,
+                               err_data: Vec::new(),
+                               msg: "Got non final data with an HMAC of 0",
+                       })
+               },
+       };
+       // final_incorrect_cltv_expiry
+       if outgoing_cltv_value > cltv_expiry {
+               return Err(InboundOnionErr {
+                       msg: "Upstream node set CLTV to less than the CLTV set by the sender",
+                       err_code: 18,
+                       err_data: cltv_expiry.to_be_bytes().to_vec()
+               })
+       }
+       // final_expiry_too_soon
+       // We have to have some headroom to broadcast on chain if we have the preimage, so make sure
+       // we have at least HTLC_FAIL_BACK_BUFFER blocks to go.
+       //
+       // Also, ensure that, in the case of an unknown preimage for the received payment hash, our
+       // payment logic has enough time to fail the HTLC backward before our onchain logic triggers a
+       // channel closure (see HTLC_FAIL_BACK_BUFFER rationale).
+       if cltv_expiry <= current_height + HTLC_FAIL_BACK_BUFFER + 1 {
+               let mut err_data = Vec::with_capacity(12);
+               err_data.extend_from_slice(&amt_msat.to_be_bytes());
+               err_data.extend_from_slice(&current_height.to_be_bytes());
+               return Err(InboundOnionErr {
+                       err_code: 0x4000 | 15, err_data,
+                       msg: "The final CLTV expiry is too soon to handle",
+               });
+       }
+       if (!allow_underpay && onion_amt_msat > amt_msat) ||
+               (allow_underpay && onion_amt_msat >
+                amt_msat.saturating_add(counterparty_skimmed_fee_msat.unwrap_or(0)))
+       {
+               return Err(InboundOnionErr {
+                       err_code: 19,
+                       err_data: amt_msat.to_be_bytes().to_vec(),
+                       msg: "Upstream node sent less than we were supposed to receive in payment",
+               });
+       }
+
+       let routing = if let Some(payment_preimage) = keysend_preimage {
+               // We need to check that the sender knows the keysend preimage before processing this
+               // payment further. Otherwise, an intermediary routing hop forwarding non-keysend-HTLC X
+               // could discover the final destination of X, by probing the adjacent nodes on the route
+               // with a keysend payment of identical payment hash to X and observing the processing
+               // time discrepancies due to a hash collision with X.
+               let hashed_preimage = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
+               if hashed_preimage != payment_hash {
+                       return Err(InboundOnionErr {
+                               err_code: 0x4000|22,
+                               err_data: Vec::new(),
+                               msg: "Payment preimage didn't match payment hash",
+                       });
+               }
+               if !accept_mpp_keysend && payment_data.is_some() {
+                       return Err(InboundOnionErr {
+                               err_code: 0x4000|22,
+                               err_data: Vec::new(),
+                               msg: "We don't support MPP keysend payments",
+                       });
+               }
+               PendingHTLCRouting::ReceiveKeysend {
+                       payment_data,
+                       payment_preimage,
+                       payment_metadata,
+                       incoming_cltv_expiry: outgoing_cltv_value,
+                       custom_tlvs,
+               }
+       } else if let Some(data) = payment_data {
+               PendingHTLCRouting::Receive {
+                       payment_data: data,
+                       payment_metadata,
+                       incoming_cltv_expiry: outgoing_cltv_value,
+                       phantom_shared_secret,
+                       custom_tlvs,
+               }
+       } else {
+               return Err(InboundOnionErr {
+                       err_code: 0x4000|0x2000|3,
+                       err_data: Vec::new(),
+                       msg: "We require payment_secrets",
+               });
+       };
+       Ok(PendingHTLCInfo {
+               routing,
+               payment_hash,
+               incoming_shared_secret: shared_secret,
+               incoming_amt_msat: Some(amt_msat),
+               outgoing_amt_msat: onion_amt_msat,
+               outgoing_cltv_value,
+               skimmed_fee_msat: counterparty_skimmed_fee_msat,
+       })
+}
+
+/// Peel one layer off an incoming onion, returning [`PendingHTLCInfo`] (either Forward or Receive).
+/// This does all the relevant context-free checks that LDK requires for payment relay or
+/// acceptance. If the payment is to be received, and the amount matches the expected amount for
+/// a given invoice, this indicates the [`msgs::UpdateAddHTLC`], once fully committed in the
+/// channel, will generate an [`Event::PaymentClaimable`].
+pub fn peel_payment_onion<NS: Deref, L: Deref, T: secp256k1::Verification>(
+       msg: &msgs::UpdateAddHTLC, node_signer: &NS, logger: &L, secp_ctx: &Secp256k1<T>,
+       cur_height: u32, accept_mpp_keysend: bool,
+) -> Result<PendingHTLCInfo, InboundOnionErr>
+where
+       NS::Target: NodeSigner,
+       L::Target: Logger,
+{
+       let (hop, shared_secret, next_packet_details_opt) =
+               decode_incoming_update_add_htlc_onion(msg, node_signer, logger, secp_ctx
+       ).map_err(|e| {
+               let (err_code, err_data) = match e {
+                       HTLCFailureMsg::Malformed(m) => (m.failure_code, Vec::new()),
+                       HTLCFailureMsg::Relay(r) => (0x4000 | 22, r.reason.data),
+               };
+               let msg = "Failed to decode update add htlc onion";
+               InboundOnionErr { msg, err_code, err_data }
+       })?;
+       Ok(match hop {
+               onion_utils::Hop::Forward { next_hop_data, next_hop_hmac, new_packet_bytes } => {
+                       let NextPacketDetails {
+                               next_packet_pubkey, outgoing_amt_msat: _, outgoing_scid: _, outgoing_cltv_value
+                       } = match next_packet_details_opt {
+                               Some(next_packet_details) => next_packet_details,
+                               // Forward should always include the next hop details
+                               None => return Err(InboundOnionErr {
+                                       msg: "Failed to decode update add htlc onion",
+                                       err_code: 0x4000 | 22,
+                                       err_data: Vec::new(),
+                               }),
+                       };
+
+                       if let Err((err_msg, code)) = check_incoming_htlc_cltv(
+                               cur_height, outgoing_cltv_value, msg.cltv_expiry
+                       ) {
+                               return Err(InboundOnionErr {
+                                       msg: err_msg,
+                                       err_code: code,
+                                       err_data: Vec::new(),
+                               });
+                       }
+                       create_fwd_pending_htlc_info(
+                               msg, next_hop_data, next_hop_hmac, new_packet_bytes, shared_secret,
+                               Some(next_packet_pubkey)
+                       )?
+               },
+               onion_utils::Hop::Receive(received_data) => {
+                       create_recv_pending_htlc_info(
+                               received_data, shared_secret, msg.payment_hash, msg.amount_msat, msg.cltv_expiry,
+                               None, false, msg.skimmed_fee_msat, cur_height, accept_mpp_keysend,
+                       )?
+               }
+       })
+}
+
+struct NextPacketDetails {
+       next_packet_pubkey: Result<PublicKey, secp256k1::Error>,
+       outgoing_scid: u64,
+       outgoing_amt_msat: u64,
+       outgoing_cltv_value: u32,
+}
+
+fn decode_incoming_update_add_htlc_onion<NS: Deref, L: Deref, T: secp256k1::Verification>(
+       msg: &msgs::UpdateAddHTLC, node_signer: &NS, logger: &L, secp_ctx: &Secp256k1<T>,
+) -> Result<(onion_utils::Hop, [u8; 32], Option<NextPacketDetails>), HTLCFailureMsg>
+where
+       NS::Target: NodeSigner,
+       L::Target: Logger,
+{
+       macro_rules! return_malformed_err {
+               ($msg: expr, $err_code: expr) => {
+                       {
+                               log_info!(logger, "Failed to accept/forward incoming HTLC: {}", $msg);
+                               return Err(HTLCFailureMsg::Malformed(msgs::UpdateFailMalformedHTLC {
+                                       channel_id: msg.channel_id,
+                                       htlc_id: msg.htlc_id,
+                                       sha256_of_onion: Sha256::hash(&msg.onion_routing_packet.hop_data).into_inner(),
+                                       failure_code: $err_code,
+                               }));
+                       }
+               }
+       }
+
+       if let Err(_) = msg.onion_routing_packet.public_key {
+               return_malformed_err!("invalid ephemeral pubkey", 0x8000 | 0x4000 | 6);
+       }
+
+       let shared_secret = node_signer.ecdh(
+               Recipient::Node, &msg.onion_routing_packet.public_key.unwrap(), None
+       ).unwrap().secret_bytes();
+
+       if msg.onion_routing_packet.version != 0 {
+               //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
+               //sha256_of_onion error data packets), or the entire onion_routing_packet. Either way,
+               //the hash doesn't really serve any purpose - in the case of hashing all data, the
+               //receiving node would have to brute force to figure out which version was put in the
+               //packet by the node that send us the message, in the case of hashing the hop_data, the
+               //node knows the HMAC matched, so they already know what is there...
+               return_malformed_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4);
+       }
+       macro_rules! return_err {
+               ($msg: expr, $err_code: expr, $data: expr) => {
+                       {
+                               log_info!(logger, "Failed to accept/forward incoming HTLC: {}", $msg);
+                               return Err(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
+                                       channel_id: msg.channel_id,
+                                       htlc_id: msg.htlc_id,
+                                       reason: HTLCFailReason::reason($err_code, $data.to_vec())
+                                               .get_encrypted_failure_packet(&shared_secret, &None),
+                               }));
+                       }
+               }
+       }
+
+       let next_hop = match onion_utils::decode_next_payment_hop(
+               shared_secret, &msg.onion_routing_packet.hop_data[..], msg.onion_routing_packet.hmac,
+               msg.payment_hash, node_signer
+       ) {
+               Ok(res) => res,
+               Err(onion_utils::OnionDecodeErr::Malformed { err_msg, err_code }) => {
+                       return_malformed_err!(err_msg, err_code);
+               },
+               Err(onion_utils::OnionDecodeErr::Relay { err_msg, err_code }) => {
+                       return_err!(err_msg, err_code, &[0; 0]);
+               },
+       };
+
+       let next_packet_details = match next_hop {
+               onion_utils::Hop::Forward {
+                       next_hop_data: msgs::InboundOnionPayload::Forward {
+                               short_channel_id, amt_to_forward, outgoing_cltv_value
+                       }, ..
+               } => {
+                       let next_packet_pubkey = onion_utils::next_hop_pubkey(secp_ctx,
+                               msg.onion_routing_packet.public_key.unwrap(), &shared_secret);
+                       NextPacketDetails {
+                               next_packet_pubkey, outgoing_scid: short_channel_id,
+                               outgoing_amt_msat: amt_to_forward, outgoing_cltv_value
+                       }
+               },
+               onion_utils::Hop::Receive { .. } => return Ok((next_hop, shared_secret, None)),
+               onion_utils::Hop::Forward { next_hop_data: msgs::InboundOnionPayload::Receive { .. }, .. } |
+                       onion_utils::Hop::Forward { next_hop_data: msgs::InboundOnionPayload::BlindedReceive { .. }, .. } =>
+               {
+                       return_err!("Final Node OnionHopData provided for us as an intermediary node", 0x4000 | 22, &[0; 0]);
+               }
+       };
+
+       Ok((next_hop, shared_secret, Some(next_packet_details)))
+}
+
+fn check_incoming_htlc_cltv(
+       cur_height: u32, outgoing_cltv_value: u32, cltv_expiry: u32
+) -> Result<(), (&'static str, u16)> {
+       if (cltv_expiry as u64) < (outgoing_cltv_value) as u64 + MIN_CLTV_EXPIRY_DELTA as u64 {
+               return Err((
+                       "Forwarding node has tampered with the intended HTLC values or origin node has an obsolete cltv_expiry_delta",
+                       0x1000 | 13, // incorrect_cltv_expiry
+               ));
+       }
+       // Theoretically, channel counterparty shouldn't send us a HTLC expiring now,
+       // but we want to be robust wrt to counterparty packet sanitization (see
+       // HTLC_FAIL_BACK_BUFFER rationale).
+       if cltv_expiry <= cur_height + HTLC_FAIL_BACK_BUFFER as u32 { // expiry_too_soon
+               return Err(("CLTV expiry is too close", 0x1000 | 14));
+       }
+       if cltv_expiry > cur_height + CLTV_FAR_FAR_AWAY as u32 { // expiry_too_far
+               return Err(("CLTV expiry is too far in the future", 21));
+       }
+       // If the HTLC expires ~now, don't bother trying to forward it to our
+       // counterparty. They should fail it anyway, but we don't want to bother with
+       // the round-trips or risk them deciding they definitely want the HTLC and
+       // force-closing to ensure they get it if we're offline.
+       // We previously had a much more aggressive check here which tried to ensure
+       // our counterparty receives an HTLC which has *our* risk threshold met on it,
+       // but there is no need to do that, and since we're a bit conservative with our
+       // risk threshold it just results in failing to forward payments.
+       if (outgoing_cltv_value) as u64 <= (cur_height + LATENCY_GRACE_PERIOD_BLOCKS) as u64 {
+               return Err(("Outgoing CLTV value is too soon", 0x1000 | 14));
+       }
+
+       Ok(())
+}
+
 impl<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref> MessageSendEventsProvider for ChannelManager<M, T, ES, NS, SP, F, R, L>
 where
        M::Target: chain::Watch<<SP::Target as SignerProvider>::Signer>,
@@ -7884,35 +8478,41 @@ where
                self.best_block.read().unwrap().clone()
        }
 
-       /// Fetches the set of [`NodeFeatures`] flags which are provided by or required by
+       /// Fetches the set of [`NodeFeatures`] flags that are provided by or required by
        /// [`ChannelManager`].
        pub fn node_features(&self) -> NodeFeatures {
                provided_node_features(&self.default_configuration)
        }
 
-       /// Fetches the set of [`Bolt11InvoiceFeatures`] flags which are provided by or required by
+       /// Fetches the set of [`Bolt11InvoiceFeatures`] flags that are provided by or required by
        /// [`ChannelManager`].
        ///
        /// Note that the invoice feature flags can vary depending on if the invoice is a "phantom invoice"
        /// or not. Thus, this method is not public.
        #[cfg(any(feature = "_test_utils", test))]
-       pub fn invoice_features(&self) -> Bolt11InvoiceFeatures {
-               provided_invoice_features(&self.default_configuration)
+       pub fn bolt11_invoice_features(&self) -> Bolt11InvoiceFeatures {
+               provided_bolt11_invoice_features(&self.default_configuration)
+       }
+
+       /// Fetches the set of [`Bolt12InvoiceFeatures`] flags that are provided by or required by
+       /// [`ChannelManager`].
+       fn bolt12_invoice_features(&self) -> Bolt12InvoiceFeatures {
+               provided_bolt12_invoice_features(&self.default_configuration)
        }
 
-       /// Fetches the set of [`ChannelFeatures`] flags which are provided by or required by
+       /// Fetches the set of [`ChannelFeatures`] flags that are provided by or required by
        /// [`ChannelManager`].
        pub fn channel_features(&self) -> ChannelFeatures {
                provided_channel_features(&self.default_configuration)
        }
 
-       /// Fetches the set of [`ChannelTypeFeatures`] flags which are provided by or required by
+       /// Fetches the set of [`ChannelTypeFeatures`] flags that are provided by or required by
        /// [`ChannelManager`].
        pub fn channel_type_features(&self) -> ChannelTypeFeatures {
                provided_channel_type_features(&self.default_configuration)
        }
 
-       /// Fetches the set of [`InitFeatures`] flags which are provided by or required by
+       /// Fetches the set of [`InitFeatures`] flags that are provided by or required by
        /// [`ChannelManager`].
        pub fn init_features(&self) -> InitFeatures {
                provided_init_features(&self.default_configuration)
@@ -8443,7 +9043,128 @@ where
        }
 }
 
-/// Fetches the set of [`NodeFeatures`] flags which are provided by or required by
+impl<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref>
+OffersMessageHandler for ChannelManager<M, T, ES, NS, SP, F, R, L>
+where
+       M::Target: chain::Watch<<SP::Target as SignerProvider>::Signer>,
+       T::Target: BroadcasterInterface,
+       ES::Target: EntropySource,
+       NS::Target: NodeSigner,
+       SP::Target: SignerProvider,
+       F::Target: FeeEstimator,
+       R::Target: Router,
+       L::Target: Logger,
+{
+       fn handle_message(&self, message: OffersMessage) -> Option<OffersMessage> {
+               let secp_ctx = &self.secp_ctx;
+               let expanded_key = &self.inbound_payment_key;
+
+               match message {
+                       OffersMessage::InvoiceRequest(invoice_request) => {
+                               let amount_msats = match InvoiceBuilder::<DerivedSigningPubkey>::amount_msats(
+                                       &invoice_request
+                               ) {
+                                       Ok(amount_msats) => Some(amount_msats),
+                                       Err(error) => return Some(OffersMessage::InvoiceError(error.into())),
+                               };
+                               let invoice_request = match invoice_request.verify(expanded_key, secp_ctx) {
+                                       Ok(invoice_request) => invoice_request,
+                                       Err(()) => {
+                                               let error = Bolt12SemanticError::InvalidMetadata;
+                                               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),
+                                               }
+                                       },
+                                       Err(()) => {
+                                               Some(OffersMessage::InvoiceError(Bolt12SemanticError::InvalidAmount.into()))
+                                       },
+                               }
+                       },
+                       OffersMessage::Invoice(invoice) => {
+                               match invoice.verify(expanded_key, secp_ctx) {
+                                       Err(()) => {
+                                               Some(OffersMessage::InvoiceError(InvoiceError::from_string("Unrecognized invoice".to_owned())))
+                                       },
+                                       Ok(_) if invoice.invoice_features().requires_unknown_bits_from(&self.bolt12_invoice_features()) => {
+                                               Some(OffersMessage::InvoiceError(Bolt12SemanticError::UnknownRequiredFeatures.into()))
+                                       },
+                                       Ok(payment_id) => {
+                                               if let Err(e) = self.send_payment_for_bolt12_invoice(&invoice, payment_id) {
+                                                       log_trace!(self.logger, "Failed paying invoice: {:?}", e);
+                                                       Some(OffersMessage::InvoiceError(InvoiceError::from_string(format!("{:?}", e))))
+                                               } else {
+                                                       None
+                                               }
+                                       },
+                               }
+                       },
+                       OffersMessage::InvoiceError(invoice_error) => {
+                               log_trace!(self.logger, "Received invoice_error: {}", invoice_error);
+                               None
+                       },
+               }
+       }
+
+       fn release_pending_messages(&self) -> Vec<PendingOnionMessage<OffersMessage>> {
+               core::mem::take(&mut self.pending_offers_messages.lock().unwrap())
+       }
+}
+
+/// Fetches the set of [`NodeFeatures`] flags that are provided by or required by
 /// [`ChannelManager`].
 pub(crate) fn provided_node_features(config: &UserConfig) -> NodeFeatures {
        let mut node_features = provided_init_features(config).to_context();
@@ -8451,29 +9172,35 @@ pub(crate) fn provided_node_features(config: &UserConfig) -> NodeFeatures {
        node_features
 }
 
-/// Fetches the set of [`Bolt11InvoiceFeatures`] flags which are provided by or required by
+/// Fetches the set of [`Bolt11InvoiceFeatures`] flags that are provided by or required by
 /// [`ChannelManager`].
 ///
 /// Note that the invoice feature flags can vary depending on if the invoice is a "phantom invoice"
 /// or not. Thus, this method is not public.
 #[cfg(any(feature = "_test_utils", test))]
-pub(crate) fn provided_invoice_features(config: &UserConfig) -> Bolt11InvoiceFeatures {
+pub(crate) fn provided_bolt11_invoice_features(config: &UserConfig) -> Bolt11InvoiceFeatures {
+       provided_init_features(config).to_context()
+}
+
+/// Fetches the set of [`Bolt12InvoiceFeatures`] flags that are provided by or required by
+/// [`ChannelManager`].
+pub(crate) fn provided_bolt12_invoice_features(config: &UserConfig) -> Bolt12InvoiceFeatures {
        provided_init_features(config).to_context()
 }
 
-/// Fetches the set of [`ChannelFeatures`] flags which are provided by or required by
+/// Fetches the set of [`ChannelFeatures`] flags that are provided by or required by
 /// [`ChannelManager`].
 pub(crate) fn provided_channel_features(config: &UserConfig) -> ChannelFeatures {
        provided_init_features(config).to_context()
 }
 
-/// Fetches the set of [`ChannelTypeFeatures`] flags which are provided by or required by
+/// Fetches the set of [`ChannelTypeFeatures`] flags that are provided by or required by
 /// [`ChannelManager`].
 pub(crate) fn provided_channel_type_features(config: &UserConfig) -> ChannelTypeFeatures {
        ChannelTypeFeatures::from_init(&provided_init_features(config))
 }
 
-/// Fetches the set of [`InitFeatures`] flags which are provided by or required by
+/// Fetches the set of [`InitFeatures`] flags that are provided by or required by
 /// [`ChannelManager`].
 pub fn provided_init_features(config: &UserConfig) -> InitFeatures {
        // Note that if new features are added here which other peers may (eventually) require, we
@@ -9384,16 +10111,16 @@ where
                                                log_error!(args.logger, " The ChannelMonitor for channel {} is at counterparty commitment transaction number {} but the ChannelManager is at counterparty commitment transaction number {}.",
                                                        &channel.context.channel_id(), monitor.get_cur_counterparty_commitment_number(), channel.get_cur_counterparty_commitment_transaction_number());
                                        }
-                                       let (monitor_update, mut new_failed_htlcs, batch_funding_txid) = channel.context.force_shutdown(true);
-                                       if batch_funding_txid.is_some() {
+                                       let mut shutdown_result = channel.context.force_shutdown(true);
+                                       if shutdown_result.unbroadcasted_batch_funding_txid.is_some() {
                                                return Err(DecodeError::InvalidValue);
                                        }
-                                       if let Some((counterparty_node_id, funding_txo, update)) = monitor_update {
+                                       if let Some((counterparty_node_id, funding_txo, update)) = shutdown_result.monitor_update {
                                                close_background_events.push(BackgroundEvent::MonitorUpdateRegeneratedOnStartup {
                                                        counterparty_node_id, funding_txo, update
                                                });
                                        }
-                                       failed_htlcs.append(&mut new_failed_htlcs);
+                                       failed_htlcs.append(&mut shutdown_result.dropped_outbound_htlcs);
                                        channel_closures.push_back((events::Event::ChannelClosed {
                                                channel_id: channel.context.channel_id(),
                                                user_channel_id: channel.context.get_user_id(),
@@ -10082,6 +10809,9 @@ where
                                                                Some((blocked_node_id, blocked_channel_outpoint, blocking_action)), ..
                                                } = action {
                                                        if let Some(blocked_peer_state) = per_peer_state.get(&blocked_node_id) {
+                                                               log_trace!(args.logger,
+                                                                       "Holding the next revoke_and_ack from {} until the preimage is durably persisted in the inbound edge's ChannelMonitor",
+                                                                       blocked_channel_outpoint.to_channel_id());
                                                                blocked_peer_state.lock().unwrap().actions_blocking_raa_monitor_updates
                                                                        .entry(blocked_channel_outpoint.to_channel_id())
                                                                        .or_insert_with(Vec::new).push(blocking_action.clone());
@@ -10093,6 +10823,9 @@ where
                                                                // anymore.
                                                        }
                                                }
+                                               if let MonitorUpdateCompletionAction::FreeOtherChannelImmediately { .. } = action {
+                                                       debug_assert!(false, "Non-event-generating channel freeing should not appear in our queue");
+                                               }
                                        }
                                }
                                peer_state.lock().unwrap().monitor_update_blocked_actions = monitor_update_blocked_actions;
@@ -10143,6 +10876,8 @@ where
 
                        funding_batch_states: Mutex::new(BTreeMap::new()),
 
+                       pending_offers_messages: Mutex::new(Vec::new()),
+
                        entropy_source: args.entropy_source,
                        node_signer: args.node_signer,
                        signer_provider: args.signer_provider,
@@ -10163,7 +10898,7 @@ where
                        // don't remember in the `ChannelMonitor` where we got a preimage from, but if the
                        // channel is closed we just assume that it probably came from an on-chain claim.
                        channel_manager.claim_funds_internal(source, preimage, Some(downstream_value),
-                               downstream_closed, downstream_node_id, downstream_funding);
+                               downstream_closed, true, downstream_node_id, downstream_funding);
                }
 
                //TODO: Broadcast channel update for closed channels, but only after we've made a
@@ -10182,11 +10917,12 @@ mod tests {
        use crate::events::{Event, HTLCDestination, MessageSendEvent, MessageSendEventsProvider, ClosureReason};
        use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
        use crate::ln::ChannelId;
-       use crate::ln::channelmanager::{inbound_payment, PaymentId, PaymentSendFailure, RecipientOnionFields, InterceptId};
+       use crate::ln::channelmanager::{create_recv_pending_htlc_info, inbound_payment, PaymentId, PaymentSendFailure, RecipientOnionFields, InterceptId};
+       use crate::ln::features::{ChannelFeatures, NodeFeatures};
        use crate::ln::functional_test_utils::*;
        use crate::ln::msgs::{self, ErrorAction};
        use crate::ln::msgs::ChannelMessageHandler;
-       use crate::routing::router::{PaymentParameters, RouteParameters, find_route};
+       use crate::routing::router::{Path, PaymentParameters, RouteHop, RouteParameters, find_route};
        use crate::util::errors::APIError;
        use crate::util::test_utils;
        use crate::util::config::{ChannelConfig, ChannelConfigUpdate};
@@ -11184,9 +11920,11 @@ mod tests {
                };
                // Check that if the amount we received + the penultimate hop extra fee is less than the sender
                // intended amount, we fail the payment.
+               let current_height: u32 = node[0].node.best_block.read().unwrap().height();
                if let Err(crate::ln::channelmanager::InboundOnionErr { err_code, .. }) =
-                       node[0].node.construct_recv_pending_htlc_info(hop_data, [0; 32], PaymentHash([0; 32]),
-                               sender_intended_amt_msat - extra_fee_msat - 1, 42, None, true, Some(extra_fee_msat))
+                       create_recv_pending_htlc_info(hop_data, [0; 32], PaymentHash([0; 32]),
+                               sender_intended_amt_msat - extra_fee_msat - 1, 42, None, true, Some(extra_fee_msat),
+                               current_height, node[0].node.default_configuration.accept_mpp_keysend)
                {
                        assert_eq!(err_code, 19);
                } else { panic!(); }
@@ -11202,8 +11940,10 @@ mod tests {
                        }),
                        custom_tlvs: Vec::new(),
                };
-               assert!(node[0].node.construct_recv_pending_htlc_info(hop_data, [0; 32], PaymentHash([0; 32]),
-                       sender_intended_amt_msat - extra_fee_msat, 42, None, true, Some(extra_fee_msat)).is_ok());
+               let current_height: u32 = node[0].node.best_block.read().unwrap().height();
+               assert!(create_recv_pending_htlc_info(hop_data, [0; 32], PaymentHash([0; 32]),
+                       sender_intended_amt_msat - extra_fee_msat, 42, None, true, Some(extra_fee_msat),
+                       current_height, node[0].node.default_configuration.accept_mpp_keysend).is_ok());
        }
 
        #[test]
@@ -11213,7 +11953,8 @@ mod tests {
                let node_chanmgr = create_node_chanmgrs(1, &node_cfg, &[None]);
                let node = create_network(1, &node_cfg, &node_chanmgr);
 
-               let result = node[0].node.construct_recv_pending_htlc_info(msgs::InboundOnionPayload::Receive {
+               let current_height: u32 = node[0].node.best_block.read().unwrap().height();
+               let result = create_recv_pending_htlc_info(msgs::InboundOnionPayload::Receive {
                        amt_msat: 100,
                        outgoing_cltv_value: 22,
                        payment_metadata: None,
@@ -11222,7 +11963,8 @@ mod tests {
                                payment_secret: PaymentSecret([0; 32]), total_msat: 100,
                        }),
                        custom_tlvs: Vec::new(),
-               }, [0; 32], PaymentHash([0; 32]), 100, 23, None, true, None);
+               }, [0; 32], PaymentHash([0; 32]), 100, 23, None, true, None, current_height,
+                       node[0].node.default_configuration.accept_mpp_keysend);
 
                // Should not return an error as this condition:
                // https://github.com/lightning/bolts/blob/4dcc377209509b13cf89a4b91fde7d478f5b46d8/04-onion-routing.md?plain=1#L334
@@ -11456,6 +12198,137 @@ mod tests {
                        check_spends!(txn[0], funding_tx);
                }
        }
+
+       #[test]
+       fn test_peel_payment_onion() {
+               use super::*;
+               let secp_ctx = Secp256k1::new();
+
+               let bob = crate::sign::KeysManager::new(&[2; 32], 42, 42);
+               let bob_pk = PublicKey::from_secret_key(&secp_ctx, &bob.get_node_secret_key());
+               let charlie = crate::sign::KeysManager::new(&[3; 32], 42, 42);
+               let charlie_pk = PublicKey::from_secret_key(&secp_ctx, &charlie.get_node_secret_key());
+
+               let (session_priv, total_amt_msat, cur_height, recipient_onion, preimage, payment_hash,
+                       prng_seed, hops, recipient_amount, pay_secret) = payment_onion_args(bob_pk, charlie_pk);
+
+               let path = Path {
+                       hops: hops,
+                       blinded_tail: None,
+               };
+
+               let (amount_msat, cltv_expiry, onion) = create_payment_onion(
+                       &secp_ctx, &path, &session_priv, total_amt_msat, recipient_onion, cur_height,
+                       payment_hash, Some(preimage), prng_seed
+               ).unwrap();
+
+               let msg = make_update_add_msg(amount_msat, cltv_expiry, payment_hash, onion);
+               let logger = test_utils::TestLogger::with_id("bob".to_string());
+
+               let peeled = peel_payment_onion(&msg, &&bob, &&logger, &secp_ctx, cur_height, true)
+                       .map_err(|e| e.msg).unwrap();
+
+               let next_onion = match peeled.routing {
+                       PendingHTLCRouting::Forward { onion_packet, short_channel_id: _ } => {
+                               onion_packet
+                       },
+                       _ => panic!("expected a forwarded onion"),
+               };
+
+               let msg2 = make_update_add_msg(amount_msat, cltv_expiry, payment_hash, next_onion);
+               let peeled2 = peel_payment_onion(&msg2, &&charlie, &&logger, &secp_ctx, cur_height, true)
+                       .map_err(|e| e.msg).unwrap();
+
+               match peeled2.routing {
+                       PendingHTLCRouting::ReceiveKeysend { payment_preimage, payment_data, incoming_cltv_expiry, .. } => {
+                               assert_eq!(payment_preimage, preimage);
+                               assert_eq!(peeled2.outgoing_amt_msat, recipient_amount);
+                               assert_eq!(incoming_cltv_expiry, peeled2.outgoing_cltv_value);
+                               let msgs::FinalOnionHopData{total_msat, payment_secret} = payment_data.unwrap();
+                               assert_eq!(total_msat, total_amt_msat);
+                               assert_eq!(payment_secret, pay_secret);
+                       },
+                       _ => panic!("expected a received keysend"),
+               };
+       }
+
+       fn make_update_add_msg(
+               amount_msat: u64, cltv_expiry: u32, payment_hash: PaymentHash,
+               onion_routing_packet: msgs::OnionPacket
+       ) -> msgs::UpdateAddHTLC {
+               msgs::UpdateAddHTLC {
+                       channel_id: ChannelId::from_bytes([0; 32]),
+                       htlc_id: 0,
+                       amount_msat,
+                       cltv_expiry,
+                       payment_hash,
+                       onion_routing_packet,
+                       skimmed_fee_msat: None,
+               }
+       }
+
+       fn payment_onion_args(hop_pk: PublicKey, recipient_pk: PublicKey) -> (
+               SecretKey, u64, u32, RecipientOnionFields, PaymentPreimage, PaymentHash, [u8; 32],
+               Vec<RouteHop>, u64, PaymentSecret,
+       ) {
+               let session_priv_bytes = [42; 32];
+               let session_priv = SecretKey::from_slice(&session_priv_bytes).unwrap();
+               let total_amt_msat = 1000;
+               let cur_height = 1000;
+               let pay_secret = PaymentSecret([99; 32]);
+               let recipient_onion = RecipientOnionFields::secret_only(pay_secret);
+               let preimage_bytes = [43; 32];
+               let preimage = PaymentPreimage(preimage_bytes);
+               let rhash_bytes = Sha256::hash(&preimage_bytes).into_inner();
+               let payment_hash = PaymentHash(rhash_bytes);
+               let prng_seed = [44; 32];
+
+               // make a route alice -> bob -> charlie
+               let hop_fee = 1;
+               let recipient_amount = total_amt_msat - hop_fee;
+               let hops = vec![
+                       RouteHop {
+                               pubkey: hop_pk,
+                               fee_msat: hop_fee,
+                               cltv_expiry_delta: 42,
+                               short_channel_id: 1,
+                               node_features: NodeFeatures::empty(),
+                               channel_features: ChannelFeatures::empty(),
+                               maybe_announced_channel: false,
+                       },
+                       RouteHop {
+                               pubkey: recipient_pk,
+                               fee_msat: recipient_amount,
+                               cltv_expiry_delta: 42,
+                               short_channel_id: 2,
+                               node_features: NodeFeatures::empty(),
+                               channel_features: ChannelFeatures::empty(),
+                               maybe_announced_channel: false,
+                       }
+               ];
+
+               (session_priv, total_amt_msat, cur_height, recipient_onion, preimage, payment_hash,
+                       prng_seed, hops, recipient_amount, pay_secret)
+       }
+
+       pub fn create_payment_onion<T: bitcoin::secp256k1::Signing>(
+               secp_ctx: &Secp256k1<T>, path: &Path, session_priv: &SecretKey, total_msat: u64,
+               recipient_onion: RecipientOnionFields, best_block_height: u32, payment_hash: PaymentHash,
+               keysend_preimage: Option<PaymentPreimage>, prng_seed: [u8; 32]
+       ) -> Result<(u64, u32, msgs::OnionPacket), ()> {
+               let onion_keys = super::onion_utils::construct_onion_keys(&secp_ctx, &path, &session_priv).map_err(|_| ())?;
+               let (onion_payloads, htlc_msat, htlc_cltv) = super::onion_utils::build_onion_payloads(
+                       &path,
+                       total_msat,
+                       recipient_onion,
+                       best_block_height + 1,
+                       &keysend_preimage,
+               ).map_err(|_| ())?;
+               let onion_packet = super::onion_utils::construct_onion_packet(
+                       onion_payloads, onion_keys, prng_seed, &payment_hash
+               )?;
+               Ok((htlc_msat, htlc_cltv, onion_packet))
+       }
 }
 
 #[cfg(ldk_bench)]
@@ -11620,7 +12493,7 @@ pub mod bench {
                macro_rules! send_payment {
                        ($node_a: expr, $node_b: expr) => {
                                let payment_params = PaymentParameters::from_node_id($node_b.get_our_node_id(), TEST_FINAL_CLTV)
-                                       .with_bolt11_features($node_b.invoice_features()).unwrap();
+                                       .with_bolt11_features($node_b.bolt11_invoice_features()).unwrap();
                                let mut payment_preimage = PaymentPreimage([0; 32]);
                                payment_preimage.0[0..8].copy_from_slice(&payment_count.to_le_bytes());
                                payment_count += 1;