Handle retrying sign_counterparty_commitment failures
[rust-lightning] / lightning / src / ln / channelmanager.rs
index 13b0a815ec148693491b35c43e91feea9e06399c..37a8feb446d6865bcdbe7849e9c1a854d318b4d9 100644 (file)
@@ -63,7 +63,7 @@ use crate::offers::merkle::SignError;
 use crate::offers::offer::{DerivedMetadata, Offer, OfferBuilder};
 use crate::offers::parse::Bolt12SemanticError;
 use crate::offers::refund::{Refund, RefundBuilder};
-use crate::onion_message::{Destination, OffersMessage, OffersMessageHandler, PendingOnionMessage};
+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};
@@ -457,7 +457,7 @@ 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.
@@ -827,7 +827,8 @@ 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>,
@@ -855,7 +856,8 @@ 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,
@@ -2600,7 +2602,7 @@ 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();
 
@@ -2615,10 +2617,11 @@ 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
@@ -2646,7 +2649,6 @@ where
                                                                        });
                                                                }
                                                                self.issue_channel_close_events(&chan.context, ClosureReason::HolderForceClosed);
-                                                               shutdown_result = Some((None, Vec::new(), unbroadcasted_batch_funding_txid));
                                                        }
                                                }
                                                break;
@@ -2681,11 +2683,11 @@ 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.
        ///
@@ -2697,8 +2699,8 @@ 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)
@@ -2712,8 +2714,8 @@ 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).
@@ -2731,29 +2733,27 @@ 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
@@ -2761,7 +2761,7 @@ 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();
@@ -3802,7 +3802,7 @@ where
 
                let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                let peer_state = &mut *peer_state_lock;
-               let (chan, msg) = match peer_state.channel_by_id.remove(temporary_channel_id) {
+               let (chan, msg_opt) = match peer_state.channel_by_id.remove(temporary_channel_id) {
                        Some(ChannelPhase::UnfundedOutboundV1(chan)) => {
                                let funding_txo = find_funding_output(&chan, &funding_transaction)?;
 
@@ -3841,10 +3841,12 @@ where
                                }),
                };
 
-               peer_state.pending_msg_events.push(events::MessageSendEvent::SendFundingCreated {
-                       node_id: chan.context.get_counterparty_node_id(),
-                       msg,
-               });
+               if let Some(msg) = msg_opt {
+                       peer_state.pending_msg_events.push(events::MessageSendEvent::SendFundingCreated {
+                               node_id: chan.context.get_counterparty_node_id(),
+                               msg,
+                       });
+               }
                match peer_state.channel_by_id.entry(chan.context.channel_id()) {
                        hash_map::Entry::Occupied(_) => {
                                panic!("Generated duplicate funding txid?");
@@ -3906,7 +3908,7 @@ 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.
        ///
@@ -3960,7 +3962,7 @@ 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,
@@ -4817,8 +4819,8 @@ 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() {
@@ -4828,9 +4830,9 @@ 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; }
@@ -4866,8 +4868,8 @@ 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();
@@ -4914,9 +4916,9 @@ 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; }
@@ -6229,7 +6231,7 @@ where
 
                let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                let peer_state = &mut *peer_state_lock;
-               let (chan, funding_msg, monitor) =
+               let (chan, funding_msg_opt, monitor) =
                        match peer_state.channel_by_id.remove(&msg.temporary_channel_id) {
                                Some(ChannelPhase::UnfundedInboundV1(inbound_chan)) => {
                                        match inbound_chan.funding_created(msg, best_block, &self.signer_provider, &self.logger) {
@@ -6252,9 +6254,12 @@ where
                                None => 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.temporary_channel_id))
                        };
 
-               match peer_state.channel_by_id.entry(funding_msg.channel_id) {
+               match peer_state.channel_by_id.entry(chan.context.channel_id()) {
                        hash_map::Entry::Occupied(_) => {
-                               Err(MsgHandleErrInternal::send_err_msg_no_close("Already had channel with the new channel_id".to_owned(), funding_msg.channel_id))
+                               Err(MsgHandleErrInternal::send_err_msg_no_close(
+                                       "Already had channel with the new channel_id".to_owned(),
+                                       chan.context.channel_id()
+                               ))
                        },
                        hash_map::Entry::Vacant(e) => {
                                let mut id_to_peer_lock = self.id_to_peer.lock().unwrap();
@@ -6262,7 +6267,7 @@ where
                                        hash_map::Entry::Occupied(_) => {
                                                return Err(MsgHandleErrInternal::send_err_msg_no_close(
                                                        "The funding_created message had the same funding_txid as an existing channel - funding is not possible".to_owned(),
-                                                       funding_msg.channel_id))
+                                                       chan.context.channel_id()))
                                        },
                                        hash_map::Entry::Vacant(i_e) => {
                                                let monitor_res = self.chain_monitor.watch_channel(monitor.get_funding_txo().0, monitor);
@@ -6274,10 +6279,12 @@ where
                                                        // hasn't persisted to disk yet - we can't lose money on a transaction that we haven't
                                                        // accepted payment from yet. We do, however, need to wait to send our channel_ready
                                                        // until we have persisted our monitor.
-                                                       peer_state.pending_msg_events.push(events::MessageSendEvent::SendFundingSigned {
-                                                               node_id: counterparty_node_id.clone(),
-                                                               msg: funding_msg,
-                                                       });
+                                                       if let Some(msg) = funding_msg_opt {
+                                                               peer_state.pending_msg_events.push(events::MessageSendEvent::SendFundingSigned {
+                                                                       node_id: counterparty_node_id.clone(),
+                                                                       msg,
+                                                               });
+                                                       }
 
                                                        if let ChannelPhase::Funded(chan) = e.insert(ChannelPhase::Funded(chan)) {
                                                                handle_new_monitor_update!(self, persist_state, peer_state_lock, peer_state,
@@ -6288,9 +6295,13 @@ where
                                                        Ok(())
                                                } else {
                                                        log_error!(self.logger, "Persisting initial ChannelMonitor failed, implying the funding outpoint was duplicated");
+                                                       let channel_id = match funding_msg_opt {
+                                                               Some(msg) => msg.channel_id,
+                                                               None => chan.context.channel_id(),
+                                                       };
                                                        return Err(MsgHandleErrInternal::send_err_msg_no_close(
                                                                "The funding_created message had the same funding_txid as an existing channel - funding is not possible".to_owned(),
-                                                               funding_msg.channel_id));
+                                                               channel_id));
                                                }
                                        }
                                }
@@ -6452,22 +6463,20 @@ 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(),
@@ -6480,8 +6489,8 @@ 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);
@@ -6503,7 +6512,6 @@ 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 {
@@ -7219,6 +7227,66 @@ where
                has_update
        }
 
+       /// When a call to a [`ChannelSigner`] method returns an error, this indicates that the signer
+       /// is (temporarily) unavailable, and the operation should be retried later.
+       ///
+       /// This method allows for that retry - either checking for any signer-pending messages to be
+       /// attempted in every channel, or in the specifically provided channel.
+       ///
+       /// [`ChannelSigner`]: crate::sign::ChannelSigner
+       #[cfg(test)] // This is only implemented for one signer method, and should be private until we
+                    // actually finish implementing it fully.
+       pub fn signer_unblocked(&self, channel_opt: Option<(PublicKey, ChannelId)>) {
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
+
+               let unblock_chan = |phase: &mut ChannelPhase<SP>, pending_msg_events: &mut Vec<MessageSendEvent>| {
+                       let node_id = phase.context().get_counterparty_node_id();
+                       if let ChannelPhase::Funded(chan) = phase {
+                               let msgs = chan.signer_maybe_unblocked(&self.logger);
+                               if let Some(updates) = msgs.commitment_update {
+                                       pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
+                                               node_id,
+                                               updates,
+                                       });
+                               }
+                               if let Some(msg) = msgs.funding_signed {
+                                       pending_msg_events.push(events::MessageSendEvent::SendFundingSigned {
+                                               node_id,
+                                               msg,
+                                       });
+                               }
+                               if let Some(msg) = msgs.funding_created {
+                                       pending_msg_events.push(events::MessageSendEvent::SendFundingCreated {
+                                               node_id,
+                                               msg,
+                                       });
+                               }
+                               if let Some(msg) = msgs.channel_ready {
+                                       send_channel_ready!(self, pending_msg_events, chan, msg);
+                               }
+                       }
+               };
+
+               let per_peer_state = self.per_peer_state.read().unwrap();
+               if let Some((counterparty_node_id, channel_id)) = channel_opt {
+                       if let Some(peer_state_mutex) = per_peer_state.get(&counterparty_node_id) {
+                               let mut peer_state_lock = peer_state_mutex.lock().unwrap();
+                               let peer_state = &mut *peer_state_lock;
+                               if let Some(chan) = peer_state.channel_by_id.get_mut(&channel_id) {
+                                       unblock_chan(chan, &mut peer_state.pending_msg_events);
+                               }
+                       }
+               } else {
+                       for (_cp_id, peer_state_mutex) in per_peer_state.iter() {
+                               let mut peer_state_lock = peer_state_mutex.lock().unwrap();
+                               let peer_state = &mut *peer_state_lock;
+                               for (_, chan) in peer_state.channel_by_id.iter_mut() {
+                                       unblock_chan(chan, &mut peer_state.pending_msg_events);
+                               }
+                       }
+               }
+       }
+
        /// Check whether any channels have finished removing all pending updates after a shutdown
        /// exchange and can now send a closing_signed.
        /// Returns whether any closing_signed messages were generated.
@@ -7236,15 +7304,18 @@ 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.
@@ -7259,7 +7330,6 @@ 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 }
                                                                },
@@ -7300,7 +7370,7 @@ 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);
@@ -7325,6 +7395,13 @@ where
        /// 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(
@@ -7358,6 +7435,9 @@ where
        /// 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
@@ -7365,13 +7445,21 @@ where
        /// 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>
@@ -7411,6 +7499,9 @@ where
        /// - `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
@@ -7428,6 +7519,12 @@ where
        /// 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
@@ -7438,6 +7535,7 @@ where
        /// [`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>,
@@ -7476,11 +7574,11 @@ where
 
                let mut pending_offers_messages = self.pending_offers_messages.lock().unwrap();
                if offer.paths().is_empty() {
-                       let message = PendingOnionMessage {
-                               contents: OffersMessage::InvoiceRequest(invoice_request),
-                               destination: Destination::Node(offer.signing_pubkey()),
-                               reply_path: Some(reply_path),
-                       };
+                       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).
@@ -7488,11 +7586,11 @@ where
                        // 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 = PendingOnionMessage {
-                                       contents: OffersMessage::InvoiceRequest(invoice_request.clone()),
-                                       destination: Destination::BlindedPath(path.clone()),
-                                       reply_path: Some(reply_path.clone()),
-                               };
+                               let message = new_pending_onion_message(
+                                       OffersMessage::InvoiceRequest(invoice_request.clone()),
+                                       Destination::BlindedPath(path.clone()),
+                                       Some(reply_path.clone()),
+                               );
                                pending_offers_messages.push(message);
                        }
                }
@@ -7507,6 +7605,13 @@ where
        /// [`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;
@@ -7538,19 +7643,19 @@ where
 
                                let mut pending_offers_messages = self.pending_offers_messages.lock().unwrap();
                                if refund.paths().is_empty() {
-                                       let message = PendingOnionMessage {
-                                               contents: OffersMessage::Invoice(invoice),
-                                               destination: Destination::Node(refund.payer_id()),
-                                               reply_path: Some(reply_path),
-                                       };
+                                       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 = PendingOnionMessage {
-                                                       contents: OffersMessage::Invoice(invoice.clone()),
-                                                       destination: Destination::BlindedPath(path.clone()),
-                                                       reply_path: Some(reply_path.clone()),
-                                               };
+                                               let message = new_pending_onion_message(
+                                                       OffersMessage::Invoice(invoice.clone()),
+                                                       Destination::BlindedPath(path.clone()),
+                                                       Some(reply_path.clone()),
+                                               );
                                                pending_offers_messages.push(message);
                                        }
                                }
@@ -8937,10 +9042,10 @@ where
                                                                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_str("Failed signing invoice")
+                                                                                       InvoiceError::from_string("Failed signing invoice".to_string())
                                                                        )),
                                                                        Err(SignError::Verification(_)) => Err(OffersMessage::InvoiceError(
-                                                                                       InvoiceError::from_str("Failed invoice signature verification")
+                                                                                       InvoiceError::from_string("Failed invoice signature verification".to_string())
                                                                        )),
                                                                });
                                                match response {
@@ -8956,7 +9061,7 @@ where
                        OffersMessage::Invoice(invoice) => {
                                match invoice.verify(expanded_key, secp_ctx) {
                                        Err(()) => {
-                                               Some(OffersMessage::InvoiceError(InvoiceError::from_str("Unrecognized invoice")))
+                                               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()))
@@ -8964,7 +9069,7 @@ where
                                        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_str(&format!("{:?}", e))))
+                                                       Some(OffersMessage::InvoiceError(InvoiceError::from_string(format!("{:?}", e))))
                                                } else {
                                                        None
                                                }
@@ -9930,16 +10035,16 @@ 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(),