cfg-gate async signing logic
[rust-lightning] / lightning / src / ln / channelmanager.rs
index 2f7db2278b56298577d0f140ac90a44655a84dc0..9536a9366e18506fa586d96c325b7d725e677de2 100644 (file)
@@ -111,6 +111,7 @@ use crate::ln::script::ShutdownScript;
 
 /// Information about where a received HTLC('s onion) has indicated the HTLC should go.
 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
+#[cfg_attr(test, derive(Debug, PartialEq))]
 pub enum PendingHTLCRouting {
        /// An HTLC which should be forwarded on to another node.
        Forward {
@@ -155,6 +156,8 @@ pub enum PendingHTLCRouting {
                /// [`Event::PaymentClaimable::onion_fields`] as
                /// [`RecipientOnionFields::custom_tlvs`].
                custom_tlvs: Vec<(u64, Vec<u8>)>,
+               /// Set if this HTLC is the final hop in a multi-hop blinded path.
+               requires_blinded_error: bool,
        },
        /// The onion indicates that this is for payment to us but which contains the preimage for
        /// claiming included, and is unrelated to any invoice we'd previously generated (aka a
@@ -187,7 +190,7 @@ pub enum PendingHTLCRouting {
 }
 
 /// Information used to forward or fail this HTLC that is being forwarded within a blinded path.
-#[derive(Clone, Copy, Hash, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, Hash, PartialEq, Eq)]
 pub struct BlindedForward {
        /// The `blinding_point` that was set in the inbound [`msgs::UpdateAddHTLC`], or in the inbound
        /// onion payload if we're the introduction node. Useful for calculating the next hop's
@@ -199,34 +202,57 @@ pub struct BlindedForward {
 impl PendingHTLCRouting {
        // Used to override the onion failure code and data if the HTLC is blinded.
        fn blinded_failure(&self) -> Option<BlindedFailure> {
-               // TODO: needs update when we support receiving to multi-hop blinded paths
-               if let Self::Forward { blinded: Some(_), .. } = self {
-                       Some(BlindedFailure::FromIntroductionNode)
-               } else {
-                       None
+               // TODO: needs update when we support forwarding blinded HTLCs as non-intro node
+               match self {
+                       Self::Forward { blinded: Some(_), .. } => Some(BlindedFailure::FromIntroductionNode),
+                       Self::Receive { requires_blinded_error: true, .. } => Some(BlindedFailure::FromBlindedNode),
+                       _ => None,
                }
        }
 }
 
-/// Full details of an incoming HTLC, including routing info.
+/// Information about an incoming HTLC, including the [`PendingHTLCRouting`] describing where it
+/// should go next.
 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
+#[cfg_attr(test, derive(Debug, PartialEq))]
 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.
-       /// Used encrypt failure packets in the event that the HTLC needs to be failed backwards.
+       /// The onion shared secret we build with the sender used to decrypt the onion.
+       ///
+       /// This is later used to encrypt failure packets in the event that the HTLC is failed.
        pub incoming_shared_secret: [u8; 32],
        /// Hash of the payment preimage, to lock the payment until the receiver releases the preimage.
        pub payment_hash: PaymentHash,
-       /// Amount offered by this HTLC.
-       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)
+       /// Amount received in the incoming HTLC.
+       ///
+       /// This field was added in LDK 0.0.113 and will be `None` for objects written by prior
+       /// versions.
+       pub incoming_amt_msat: Option<u64>,
+       /// The amount the sender indicated should be forwarded on to the next hop or amount the sender
+       /// intended for us to receive for received payments.
+       ///
+       /// If the received amount is less than this for received payments, an intermediary hop has
+       /// attempted to steal some of our funds and we should fail the HTLC (the sender should retry
+       /// it along another path).
+       ///
+       /// Because nodes can take less than their required fees, and because senders may wish to
+       /// improve their own privacy, this amount may be less than [`Self::incoming_amt_msat`] for
+       /// received payments. In such cases, recipients must handle this HTLC as if it had received
+       /// [`Self::outgoing_amt_msat`].
        pub outgoing_amt_msat: u64,
-       /// Outgoing timelock expiration blockheight.
+       /// The CLTV the sender has indicated we should set on the forwarded HTLC (or has indicated
+       /// should have been set on the received HTLC for received payments).
        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.
+       /// The fee taken for this HTLC in addition to the standard protocol HTLC fees.
+       ///
+       /// If this is a payment for forwarding, this is the fee we are taking before forwarding the
+       /// HTLC.
+       ///
+       /// If this is a received payment, this is the fee that our counterparty took.
+       ///
+       /// This is used to allow LSPs to take fees as a part of payments, without the sender having to
+       /// shoulder them.
        pub skimmed_fee_msat: Option<u64>,
 }
 
@@ -243,6 +269,7 @@ pub(super) enum PendingHTLCStatus {
        Fail(HTLCFailureMsg),
 }
 
+#[cfg_attr(test, derive(Clone, Debug, PartialEq))]
 pub(super) struct PendingAddHTLCInfo {
        pub(super) forward_info: PendingHTLCInfo,
 
@@ -258,19 +285,25 @@ pub(super) struct PendingAddHTLCInfo {
        prev_user_channel_id: u128,
 }
 
+#[cfg_attr(test, derive(Clone, Debug, PartialEq))]
 pub(super) enum HTLCForwardInfo {
        AddHTLC(PendingAddHTLCInfo),
        FailHTLC {
                htlc_id: u64,
                err_packet: msgs::OnionErrorPacket,
        },
+       FailMalformedHTLC {
+               htlc_id: u64,
+               failure_code: u16,
+               sha256_of_onion: [u8; 32],
+       },
 }
 
 // Used for failing blinded HTLCs backwards correctly.
-#[derive(Clone, Debug, Hash, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, Hash, PartialEq, Eq)]
 enum BlindedFailure {
        FromIntroductionNode,
-       // Another variant will be added here for non-intro nodes.
+       FromBlindedNode,
 }
 
 /// Tracks the inbound corresponding to an outbound HTLC
@@ -1499,13 +1532,11 @@ pub const MIN_FINAL_CLTV_EXPIRY_DELTA: u16 = HTLC_FAIL_BACK_BUFFER as u16 + 3;
 // then waiting ANTI_REORG_DELAY to be reorg-safe on the outbound HLTC and
 // failing the corresponding htlc backward, and us now seeing the last block of ANTI_REORG_DELAY before
 // LATENCY_GRACE_PERIOD_BLOCKS.
-#[deny(const_err)]
 #[allow(dead_code)]
 const CHECK_CLTV_EXPIRY_SANITY: u32 = MIN_CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - CLTV_CLAIM_BUFFER - ANTI_REORG_DELAY - LATENCY_GRACE_PERIOD_BLOCKS;
 
 // Check for ability of an attacker to make us fail on-chain by delaying an HTLC claim. See
 // ChannelMonitor::should_broadcast_holder_commitment_txn for a description of why this is needed.
-#[deny(const_err)]
 #[allow(dead_code)]
 const CHECK_CLTV_EXPIRY_SANITY_2: u32 = MIN_CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - 2*CLTV_CLAIM_BUFFER;
 
@@ -2692,9 +2723,10 @@ where
        fn close_channel_internal(&self, channel_id: &ChannelId, counterparty_node_id: &PublicKey, target_feerate_sats_per_1000_weight: Option<u32>, override_shutdown_script: Option<ShutdownScript>) -> Result<(), APIError> {
                let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
 
-               let mut failed_htlcs: Vec<(HTLCSource, PaymentHash)>;
-               let shutdown_result;
-               loop {
+               let mut failed_htlcs: Vec<(HTLCSource, PaymentHash)> = Vec::new();
+               let mut shutdown_result = None;
+
+               {
                        let per_peer_state = self.per_peer_state.read().unwrap();
 
                        let peer_state_mutex = per_peer_state.get(counterparty_node_id)
@@ -2708,11 +2740,9 @@ 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 (shutdown_msg, mut monitor_update_opt, htlcs, local_shutdown_result) =
+                                               let (shutdown_msg, mut monitor_update_opt, htlcs) =
                                                        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
@@ -2729,30 +2759,20 @@ where
                                                if let Some(monitor_update) = monitor_update_opt.take() {
                                                        handle_new_monitor_update!(self, funding_txo_opt.unwrap(), monitor_update,
                                                                peer_state_lock, peer_state, per_peer_state, chan);
-                                                       break;
                                                }
-
-                                               if chan.is_shutdown() {
-                                                       if let ChannelPhase::Funded(chan) = remove_channel_phase!(self, chan_phase_entry) {
-                                                               if let Ok(channel_update) = self.get_channel_update_for_broadcast(&chan) {
-                                                                       peer_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
-                                                                               msg: channel_update
-                                                                       });
-                                                               }
-                                                               self.issue_channel_close_events(&chan.context, ClosureReason::HolderForceClosed);
-                                                       }
-                                               }
-                                               break;
+                                       } else {
+                                               self.issue_channel_close_events(chan_phase_entry.get().context(), ClosureReason::HolderForceClosed);
+                                               let mut chan_phase = remove_channel_phase!(self, chan_phase_entry);
+                                               shutdown_result = Some(chan_phase.context_mut().force_shutdown(false));
                                        }
                                },
                                hash_map::Entry::Vacant(_) => {
-                                       // If we reach this point, it means that the channel_id either refers to an unfunded channel or
-                                       // it does not exist for this peer. Either way, we can attempt to force-close it.
-                                       //
-                                       // An appropriate error will be returned for non-existence of the channel if that's the case.
-                                       mem::drop(peer_state_lock);
-                                       mem::drop(per_peer_state);
-                                       return self.force_close_channel_with_peer(&channel_id, counterparty_node_id, None, false).map(|_| ())
+                                       return Err(APIError::ChannelUnavailable {
+                                               err: format!(
+                                                       "Channel with id {} not found for the passed counterparty node_id {}",
+                                                       channel_id, counterparty_node_id,
+                                               )
+                                       });
                                },
                        }
                }
@@ -3007,11 +3027,12 @@ where
                        msg, &self.node_signer, &self.logger, &self.secp_ctx
                )?;
 
-               let is_blinded = match next_hop {
+               let is_intro_node_forward = match next_hop {
                        onion_utils::Hop::Forward {
+                               // TODO: update this when we support blinded forwarding as non-intro node
                                next_hop_data: msgs::InboundOnionPayload::BlindedForward { .. }, ..
                        } => true,
-                       _ => false, // TODO: update this when we support receiving to multi-hop blinded paths
+                       _ => false,
                };
 
                macro_rules! return_err {
@@ -3021,7 +3042,17 @@ where
                                                WithContext::from(&self.logger, Some(*counterparty_node_id), Some(msg.channel_id)),
                                                "Failed to accept/forward incoming HTLC: {}", $msg
                                        );
-                                       let (err_code, err_data) = if is_blinded {
+                                       // If `msg.blinding_point` is set, we must always fail with malformed.
+                                       if msg.blinding_point.is_some() {
+                                               return Err(HTLCFailureMsg::Malformed(msgs::UpdateFailMalformedHTLC {
+                                                       channel_id: msg.channel_id,
+                                                       htlc_id: msg.htlc_id,
+                                                       sha256_of_onion: [0; 32],
+                                                       failure_code: INVALID_ONION_BLINDING,
+                                               }));
+                                       }
+
+                                       let (err_code, err_data) = if is_intro_node_forward {
                                                (INVALID_ONION_BLINDING, &[0; 32][..])
                                        } else { ($err_code, $data) };
                                        return Err(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
@@ -3174,6 +3205,16 @@ where
                                {
                                        let logger = WithContext::from(&self.logger, Some(*counterparty_node_id), Some(msg.channel_id));
                                        log_info!(logger, "Failed to accept/forward incoming HTLC: {}", $msg);
+                                       if msg.blinding_point.is_some() {
+                                               return PendingHTLCStatus::Fail(HTLCFailureMsg::Malformed(
+                                                       msgs::UpdateFailMalformedHTLC {
+                                                               channel_id: msg.channel_id,
+                                                               htlc_id: msg.htlc_id,
+                                                               sha256_of_onion: [0; 32],
+                                                               failure_code: INVALID_ONION_BLINDING,
+                                                       }
+                                               ))
+                                       }
                                        return PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
                                                channel_id: msg.channel_id,
                                                htlc_id: msg.htlc_id,
@@ -3249,7 +3290,7 @@ where
        /// [`internal_closing_signed`]: Self::internal_closing_signed
        fn get_channel_update_for_unicast(&self, chan: &Channel<SP>) -> Result<msgs::ChannelUpdate, LightningError> {
                let logger = WithChannelContext::from(&self.logger, &chan.context);
-               log_trace!(logger, "Attempting to generate channel update for channel {}", log_bytes!(chan.context.channel_id().0));
+               log_trace!(logger, "Attempting to generate channel update for channel {}", chan.context.channel_id());
                let short_channel_id = match chan.context.get_short_channel_id().or(chan.context.latest_inbound_scid_alias()) {
                        None => return Err(LightningError{err: "Channel not yet established".to_owned(), action: msgs::ErrorAction::IgnoreError}),
                        Some(id) => id,
@@ -3260,7 +3301,7 @@ where
 
        fn get_channel_update_for_onion(&self, short_channel_id: u64, chan: &Channel<SP>) -> Result<msgs::ChannelUpdate, LightningError> {
                let logger = WithChannelContext::from(&self.logger, &chan.context);
-               log_trace!(logger, "Generating channel update for channel {}", log_bytes!(chan.context.channel_id().0));
+               log_trace!(logger, "Generating channel update for channel {}", chan.context.channel_id());
                let were_node_one = self.our_network_pubkey.serialize()[..] < chan.context.get_counterparty_node_id().serialize()[..];
 
                let enabled = chan.context.is_usable() && match chan.channel_update_status() {
@@ -3708,7 +3749,7 @@ where
                let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                let peer_state = &mut *peer_state_lock;
                let (chan, msg_opt) = match peer_state.channel_by_id.remove(temporary_channel_id) {
-                       Some(ChannelPhase::UnfundedOutboundV1(chan)) => {
+                       Some(ChannelPhase::UnfundedOutboundV1(mut chan)) => {
                                let funding_txo = find_funding_output(&chan, &funding_transaction)?;
 
                                let logger = WithChannelContext::from(&self.logger, &chan.context);
@@ -3721,7 +3762,7 @@ where
                                                (chan, MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, user_id, shutdown_res, None, channel_capacity))
                                        } else { unreachable!(); });
                                match funding_res {
-                                       Ok((chan, funding_msg)) => (chan, funding_msg),
+                                       Ok(funding_msg) => (chan, funding_msg),
                                        Err((chan, err)) => {
                                                mem::drop(peer_state_lock);
                                                mem::drop(per_peer_state);
@@ -3761,7 +3802,7 @@ where
                                if id_to_peer.insert(chan.context.channel_id(), chan.context.get_counterparty_node_id()).is_some() {
                                        panic!("id_to_peer map already contained funding txid, which shouldn't be possible");
                                }
-                               e.insert(ChannelPhase::Funded(chan));
+                               e.insert(ChannelPhase::UnfundedOutboundV1(chan));
                        }
                }
                Ok(())
@@ -4237,7 +4278,7 @@ where
                                                                                                let phantom_shared_secret = self.node_signer.ecdh(Recipient::PhantomNode, &onion_packet.public_key.unwrap(), None).unwrap().secret_bytes();
                                                                                                let next_hop = match onion_utils::decode_next_payment_hop(
                                                                                                        phantom_shared_secret, &onion_packet.hop_data, onion_packet.hmac,
-                                                                                                       payment_hash, &self.node_signer
+                                                                                                       payment_hash, None, &self.node_signer
                                                                                                ) {
                                                                                                        Ok(res) => res,
                                                                                                        Err(onion_utils::OnionDecodeErr::Malformed { err_msg, err_code }) => {
@@ -4273,7 +4314,7 @@ where
                                                                                        fail_forward!(format!("Unknown short channel id {} for forward HTLC", short_chan_id), 0x4000 | 10, Vec::new(), None);
                                                                                }
                                                                        },
-                                                                       HTLCForwardInfo::FailHTLC { .. } => {
+                                                                       HTLCForwardInfo::FailHTLC { .. } | HTLCForwardInfo::FailMalformedHTLC { .. } => {
                                                                                // Channel went away before we could fail it. This implies
                                                                                // the channel is now on chain and our counterparty is
                                                                                // trying to broadcast the HTLC-Timeout, but that's their
@@ -4369,6 +4410,20 @@ where
                                                                                continue;
                                                                        }
                                                                },
+                                                               HTLCForwardInfo::FailMalformedHTLC { htlc_id, failure_code, sha256_of_onion } => {
+                                                                       log_trace!(self.logger, "Failing malformed HTLC back to channel with short id {} (backward HTLC ID {}) after delay", short_chan_id, htlc_id);
+                                                                       if let Err(e) = chan.queue_fail_malformed_htlc(htlc_id, failure_code, sha256_of_onion, &self.logger) {
+                                                                               if let ChannelError::Ignore(msg) = e {
+                                                                                       log_trace!(self.logger, "Failed to fail HTLC with ID {} backwards to short_id {}: {}", htlc_id, short_chan_id, msg);
+                                                                               } else {
+                                                                                       panic!("Stated return value requirements in queue_fail_malformed_htlc() were not met");
+                                                                               }
+                                                                               // fail-backs are best-effort, we probably already have one
+                                                                               // pending, and if not that's OK, if not, the channel is on
+                                                                               // the chain and sending the HTLC-Timeout is their problem.
+                                                                               continue;
+                                                                       }
+                                                               },
                                                        }
                                                }
                                        } else {
@@ -4387,7 +4442,10 @@ where
                                                        }) => {
                                                                let blinded_failure = routing.blinded_failure();
                                                                let (cltv_expiry, onion_payload, payment_data, phantom_shared_secret, mut onion_fields) = match routing {
-                                                                       PendingHTLCRouting::Receive { payment_data, payment_metadata, incoming_cltv_expiry, phantom_shared_secret, custom_tlvs } => {
+                                                                       PendingHTLCRouting::Receive {
+                                                                               payment_data, payment_metadata, incoming_cltv_expiry, phantom_shared_secret,
+                                                                               custom_tlvs, requires_blinded_error: _
+                                                                       } => {
                                                                                let _legacy_hop_data = Some(payment_data.clone());
                                                                                let onion_fields = RecipientOnionFields { payment_secret: Some(payment_data.payment_secret),
                                                                                                payment_metadata, custom_tlvs };
@@ -4446,7 +4504,7 @@ where
                                                                                                htlc_id: $htlc.prev_hop.htlc_id,
                                                                                                incoming_packet_shared_secret: $htlc.prev_hop.incoming_packet_shared_secret,
                                                                                                phantom_shared_secret,
-                                                                                               blinded_failure: None,
+                                                                                               blinded_failure,
                                                                                        }), payment_hash,
                                                                                        HTLCFailReason::reason(0x4000 | 15, htlc_msat_height_data),
                                                                                        HTLCDestination::FailedPayment { payment_hash: $payment_hash },
@@ -4620,7 +4678,7 @@ where
                                                                        },
                                                                };
                                                        },
-                                                       HTLCForwardInfo::FailHTLC { .. } => {
+                                                       HTLCForwardInfo::FailHTLC { .. } | HTLCForwardInfo::FailMalformedHTLC { .. } => {
                                                                panic!("Got pending fail of our own HTLC");
                                                        }
                                                }
@@ -5225,15 +5283,26 @@ where
                                        "Failing {}HTLC with payment_hash {} backwards from us: {:?}",
                                        if blinded_failure.is_some() { "blinded " } else { "" }, &payment_hash, onion_error
                                );
-                               let err_packet = match blinded_failure {
+                               let failure = match blinded_failure {
                                        Some(BlindedFailure::FromIntroductionNode) => {
                                                let blinded_onion_error = HTLCFailReason::reason(INVALID_ONION_BLINDING, vec![0; 32]);
-                                               blinded_onion_error.get_encrypted_failure_packet(
+                                               let err_packet = blinded_onion_error.get_encrypted_failure_packet(
                                                        incoming_packet_shared_secret, phantom_shared_secret
-                                               )
+                                               );
+                                               HTLCForwardInfo::FailHTLC { htlc_id: *htlc_id, err_packet }
+                                       },
+                                       Some(BlindedFailure::FromBlindedNode) => {
+                                               HTLCForwardInfo::FailMalformedHTLC {
+                                                       htlc_id: *htlc_id,
+                                                       failure_code: INVALID_ONION_BLINDING,
+                                                       sha256_of_onion: [0; 32]
+                                               }
                                        },
                                        None => {
-                                               onion_error.get_encrypted_failure_packet(incoming_packet_shared_secret, phantom_shared_secret)
+                                               let err_packet = onion_error.get_encrypted_failure_packet(
+                                                       incoming_packet_shared_secret, phantom_shared_secret
+                                               );
+                                               HTLCForwardInfo::FailHTLC { htlc_id: *htlc_id, err_packet }
                                        }
                                };
 
@@ -5244,10 +5313,10 @@ where
                                }
                                match forward_htlcs.entry(*short_channel_id) {
                                        hash_map::Entry::Occupied(mut entry) => {
-                                               entry.get_mut().push(HTLCForwardInfo::FailHTLC { htlc_id: *htlc_id, err_packet });
+                                               entry.get_mut().push(failure);
                                        },
                                        hash_map::Entry::Vacant(entry) => {
-                                               entry.insert(vec!(HTLCForwardInfo::FailHTLC { htlc_id: *htlc_id, err_packet }));
+                                               entry.insert(vec!(failure));
                                        }
                                }
                                mem::drop(forward_htlcs);
@@ -5407,7 +5476,7 @@ where
                                                // We got a temporary failure updating monitor, but will claim the
                                                // HTLC when the monitor updating is restored (or on chain).
                                                let logger = WithContext::from(&self.logger, None, Some(prev_hop_chan_id));
-                                               log_error!(self.logger, "Temporary failure claiming HTLC, treating as success: {}", err.err.err);
+                                               log_error!(logger, "Temporary failure claiming HTLC, treating as success: {}", err.err.err);
                                        } else { errs.push((pk, err)); }
                                }
                        }
@@ -6288,22 +6357,43 @@ where
                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) {
-                       hash_map::Entry::Occupied(mut chan_phase_entry) => {
-                               match chan_phase_entry.get_mut() {
-                                       ChannelPhase::Funded(ref mut chan) => {
-                                               let logger = WithChannelContext::from(&self.logger, &chan.context);
-                                               let monitor = try_chan_phase_entry!(self,
-                                                       chan.funding_signed(&msg, best_block, &self.signer_provider, &&logger), chan_phase_entry);
-                                               if let Ok(persist_status) = self.chain_monitor.watch_channel(chan.context.get_funding_txo().unwrap(), monitor) {
-                                                       handle_new_monitor_update!(self, persist_status, peer_state_lock, peer_state, per_peer_state, chan, INITIAL_MONITOR);
-                                                       Ok(())
-                                               } else {
-                                                       try_chan_phase_entry!(self, Err(ChannelError::Close("Channel funding outpoint was a duplicate".to_owned())), chan_phase_entry)
+                       hash_map::Entry::Occupied(chan_phase_entry) => {
+                               if matches!(chan_phase_entry.get(), ChannelPhase::UnfundedOutboundV1(_)) {
+                                       let chan = if let ChannelPhase::UnfundedOutboundV1(chan) = chan_phase_entry.remove() { chan } else { unreachable!() };
+                                       let logger = WithContext::from(
+                                               &self.logger,
+                                               Some(chan.context.get_counterparty_node_id()),
+                                               Some(chan.context.channel_id())
+                                       );
+                                       let res =
+                                               chan.funding_signed(&msg, best_block, &self.signer_provider, &&logger);
+                                       match res {
+                                               Ok((chan, monitor)) => {
+                                                       if let Ok(persist_status) = self.chain_monitor.watch_channel(chan.context.get_funding_txo().unwrap(), monitor) {
+                                                               // We really should be able to insert here without doing a second
+                                                               // lookup, but sadly rust stdlib doesn't currently allow keeping
+                                                               // the original Entry around with the value removed.
+                                                               let mut chan = peer_state.channel_by_id.entry(msg.channel_id).or_insert(ChannelPhase::Funded(chan));
+                                                               if let ChannelPhase::Funded(ref mut chan) = &mut chan {
+                                                                       handle_new_monitor_update!(self, persist_status, peer_state_lock, peer_state, per_peer_state, chan, INITIAL_MONITOR);
+                                                               } else { unreachable!(); }
+                                                               Ok(())
+                                                       } else {
+                                                               let e = ChannelError::Close("Channel funding outpoint was a duplicate".to_owned());
+                                                               return Err(convert_chan_phase_err!(self, e, &mut ChannelPhase::Funded(chan), &msg.channel_id).1);
+                                                       }
+                                               },
+                                               Err((chan, e)) => {
+                                                       debug_assert!(matches!(e, ChannelError::Close(_)),
+                                                               "We don't have a channel anymore, so the error better have expected close");
+                                                       // We've already removed this outbound channel from the map in
+                                                       // `PeerState` above so at this point we just need to clean up any
+                                                       // lingering entries concerning this channel as it is safe to do so.
+                                                       return Err(convert_chan_phase_err!(self, e, &mut ChannelPhase::UnfundedOutboundV1(chan), &msg.channel_id).1);
                                                }
-                                       },
-                                       _ => {
-                                               return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id));
-                                       },
+                                       }
+                               } else {
+                                       return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id));
                                }
                        },
                        hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
@@ -6526,6 +6616,16 @@ where
                                                Err(e) => PendingHTLCStatus::Fail(e)
                                        };
                                        let create_pending_htlc_status = |chan: &Channel<SP>, pending_forward_info: PendingHTLCStatus, error_code: u16| {
+                                               if msg.blinding_point.is_some() {
+                                                       return PendingHTLCStatus::Fail(HTLCFailureMsg::Malformed(
+                                                                       msgs::UpdateFailMalformedHTLC {
+                                                                               channel_id: msg.channel_id,
+                                                                               htlc_id: msg.htlc_id,
+                                                                               sha256_of_onion: [0; 32],
+                                                                               failure_code: INVALID_ONION_BLINDING,
+                                                                       }
+                                                       ))
+                                               }
                                                // If the update_add is completely bogus, the call will Err and we will close,
                                                // but if we've sent a shutdown and they haven't acknowledged it yet, we just
                                                // want to reject the new HTLC and fail it backwards instead of forwarding.
@@ -7039,7 +7139,7 @@ where
                                },
                                hash_map::Entry::Vacant(_) => {
                                        log_debug!(logger, "Sending bogus ChannelReestablish for unknown channel {} to force channel closure",
-                                               log_bytes!(msg.channel_id.0));
+                                               msg.channel_id);
                                        // Unfortunately, lnd doesn't force close on errors
                                        // (https://github.com/lightningnetwork/lnd/blob/abb1e3463f3a83bbb843d5c399869dbe930ad94f/htlcswitch/link.go#L2119).
                                        // One of the few ways to get an lnd counterparty to force close is by
@@ -7222,36 +7322,40 @@ where
        /// 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.
+       #[cfg(async_signing)]
        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,
-                                       });
+                       match phase {
+                               ChannelPhase::Funded(chan) => {
+                                       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.channel_ready {
+                                               send_channel_ready!(self, pending_msg_events, chan, msg);
+                                       }
                                }
-                               if let Some(msg) = msgs.channel_ready {
-                                       send_channel_ready!(self, pending_msg_events, chan, msg);
+                               ChannelPhase::UnfundedOutboundV1(chan) => {
+                                       if let Some(msg) = chan.signer_maybe_unblocked(&self.logger) {
+                                               pending_msg_events.push(events::MessageSendEvent::SendFundingCreated {
+                                                       node_id,
+                                                       msg,
+                                               });
+                                       }
                                }
+                               ChannelPhase::UnfundedInboundV1(_) => {},
                        }
                };
 
@@ -9336,6 +9440,7 @@ impl_writeable_tlv_based_enum!(PendingHTLCRouting,
                (2, incoming_cltv_expiry, required),
                (3, payment_metadata, option),
                (5, custom_tlvs, optional_vec),
+               (7, requires_blinded_error, (default_value, false)),
        },
        (2, ReceiveKeysend) => {
                (0, payment_preimage, required),
@@ -9430,7 +9535,8 @@ impl_writeable_tlv_based_enum!(PendingHTLCStatus, ;
 );
 
 impl_writeable_tlv_based_enum!(BlindedFailure,
-       (0, FromIntroductionNode) => {}, ;
+       (0, FromIntroductionNode) => {},
+       (2, FromBlindedNode) => {}, ;
 );
 
 impl_writeable_tlv_based!(HTLCPreviousHopData, {
@@ -9594,13 +9700,68 @@ impl_writeable_tlv_based!(PendingAddHTLCInfo, {
        (6, prev_funding_outpoint, required),
 });
 
-impl_writeable_tlv_based_enum!(HTLCForwardInfo,
-       (1, FailHTLC) => {
-               (0, htlc_id, required),
-               (2, err_packet, required),
-       };
-       (0, AddHTLC)
-);
+impl Writeable for HTLCForwardInfo {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+               const FAIL_HTLC_VARIANT_ID: u8 = 1;
+               match self {
+                       Self::AddHTLC(info) => {
+                               0u8.write(w)?;
+                               info.write(w)?;
+                       },
+                       Self::FailHTLC { htlc_id, err_packet } => {
+                               FAIL_HTLC_VARIANT_ID.write(w)?;
+                               write_tlv_fields!(w, {
+                                       (0, htlc_id, required),
+                                       (2, err_packet, required),
+                               });
+                       },
+                       Self::FailMalformedHTLC { htlc_id, failure_code, sha256_of_onion } => {
+                               // Since this variant was added in 0.0.119, write this as `::FailHTLC` with an empty error
+                               // packet so older versions have something to fail back with, but serialize the real data as
+                               // optional TLVs for the benefit of newer versions.
+                               FAIL_HTLC_VARIANT_ID.write(w)?;
+                               let dummy_err_packet = msgs::OnionErrorPacket { data: Vec::new() };
+                               write_tlv_fields!(w, {
+                                       (0, htlc_id, required),
+                                       (1, failure_code, required),
+                                       (2, dummy_err_packet, required),
+                                       (3, sha256_of_onion, required),
+                               });
+                       },
+               }
+               Ok(())
+       }
+}
+
+impl Readable for HTLCForwardInfo {
+       fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+               let id: u8 = Readable::read(r)?;
+               Ok(match id {
+                       0 => Self::AddHTLC(Readable::read(r)?),
+                       1 => {
+                               _init_and_read_len_prefixed_tlv_fields!(r, {
+                                       (0, htlc_id, required),
+                                       (1, malformed_htlc_failure_code, option),
+                                       (2, err_packet, required),
+                                       (3, sha256_of_onion, option),
+                               });
+                               if let Some(failure_code) = malformed_htlc_failure_code {
+                                       Self::FailMalformedHTLC {
+                                               htlc_id: _init_tlv_based_struct_field!(htlc_id, required),
+                                               failure_code,
+                                               sha256_of_onion: sha256_of_onion.ok_or(DecodeError::InvalidValue)?,
+                                       }
+                               } else {
+                                       Self::FailHTLC {
+                                               htlc_id: _init_tlv_based_struct_field!(htlc_id, required),
+                                               err_packet: _init_tlv_based_struct_field!(err_packet, required),
+                                       }
+                               }
+                       },
+                       _ => return Err(DecodeError::InvalidValue),
+               })
+       }
+}
 
 impl_writeable_tlv_based!(PendingInboundPayment, {
        (0, payment_secret, required),
@@ -10460,7 +10621,6 @@ where
                        // 0.0.102+
                        for (_, monitor) in args.channel_monitors.iter() {
                                let counterparty_opt = id_to_peer.get(&monitor.get_funding_txo().0.to_channel_id());
-                               let chan_id = monitor.get_funding_txo().0.to_channel_id();
                                if counterparty_opt.is_none() {
                                        let logger = WithChannelMonitor::from(&args.logger, monitor);
                                        for (htlc_source, (htlc, _)) in monitor.get_pending_or_resolved_outbound_htlcs() {
@@ -10477,7 +10637,7 @@ where
                                                                hash_map::Entry::Occupied(mut entry) => {
                                                                        let newly_added = entry.get_mut().insert(session_priv_bytes, &path);
                                                                        log_info!(logger, "{} a pending payment path for {} msat for session priv {} on an existing pending payment with payment hash {}",
-                                                                               if newly_added { "Added" } else { "Had" }, path_amt, log_bytes!(session_priv_bytes), log_bytes!(htlc.payment_hash.0));
+                                                                               if newly_added { "Added" } else { "Had" }, path_amt, log_bytes!(session_priv_bytes), htlc.payment_hash);
                                                                },
                                                                hash_map::Entry::Vacant(entry) => {
                                                                        let path_fee = path.fee_msat();
@@ -10763,8 +10923,7 @@ where
                                                        }
                                                }
                                                if let Some(previous_hop_monitor) = args.channel_monitors.get(&claimable_htlc.prev_hop.outpoint) {
-                                                       let logger = WithChannelMonitor::from(&args.logger, previous_hop_monitor);
-                                                       previous_hop_monitor.provide_payment_preimage(&payment_hash, &payment_preimage, &args.tx_broadcaster, &bounded_fee_estimator, &&logger);
+                                                       previous_hop_monitor.provide_payment_preimage(&payment_hash, &payment_preimage, &args.tx_broadcaster, &bounded_fee_estimator, &args.logger);
                                                }
                                        }
                                        pending_events_read.push_back((events::Event::PaymentClaimed {
@@ -10897,12 +11056,14 @@ mod tests {
        use crate::events::{Event, HTLCDestination, MessageSendEvent, MessageSendEventsProvider, ClosureReason};
        use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
        use crate::ln::ChannelId;
-       use crate::ln::channelmanager::{create_recv_pending_htlc_info, inbound_payment, PaymentId, PaymentSendFailure, RecipientOnionFields, InterceptId};
+       use crate::ln::channelmanager::{create_recv_pending_htlc_info, HTLCForwardInfo, inbound_payment, PaymentId, PaymentSendFailure, RecipientOnionFields, InterceptId};
        use crate::ln::functional_test_utils::*;
        use crate::ln::msgs::{self, ErrorAction};
        use crate::ln::msgs::ChannelMessageHandler;
+       use crate::prelude::*;
        use crate::routing::router::{PaymentParameters, RouteParameters, find_route};
        use crate::util::errors::APIError;
+       use crate::util::ser::Writeable;
        use crate::util::test_utils;
        use crate::util::config::{ChannelConfig, ChannelConfigUpdate};
        use crate::sign::EntropySource;
@@ -12177,6 +12338,63 @@ mod tests {
                        check_spends!(txn[0], funding_tx);
                }
        }
+
+       #[test]
+       fn test_malformed_forward_htlcs_ser() {
+               // Ensure that `HTLCForwardInfo::FailMalformedHTLC`s are (de)serialized properly.
+               let chanmon_cfg = create_chanmon_cfgs(1);
+               let node_cfg = create_node_cfgs(1, &chanmon_cfg);
+               let persister;
+               let chain_monitor;
+               let chanmgrs = create_node_chanmgrs(1, &node_cfg, &[None]);
+               let deserialized_chanmgr;
+               let mut nodes = create_network(1, &node_cfg, &chanmgrs);
+
+               let dummy_failed_htlc = |htlc_id| {
+                       HTLCForwardInfo::FailHTLC { htlc_id, err_packet: msgs::OnionErrorPacket { data: vec![42] }, }
+               };
+               let dummy_malformed_htlc = |htlc_id| {
+                       HTLCForwardInfo::FailMalformedHTLC { htlc_id, failure_code: 0x4000, sha256_of_onion: [0; 32] }
+               };
+
+               let dummy_htlcs_1: Vec<HTLCForwardInfo> = (1..10).map(|htlc_id| {
+                       if htlc_id % 2 == 0 {
+                               dummy_failed_htlc(htlc_id)
+                       } else {
+                               dummy_malformed_htlc(htlc_id)
+                       }
+               }).collect();
+
+               let dummy_htlcs_2: Vec<HTLCForwardInfo> = (1..10).map(|htlc_id| {
+                       if htlc_id % 2 == 1 {
+                               dummy_failed_htlc(htlc_id)
+                       } else {
+                               dummy_malformed_htlc(htlc_id)
+                       }
+               }).collect();
+
+
+               let (scid_1, scid_2) = (42, 43);
+               let mut forward_htlcs = HashMap::new();
+               forward_htlcs.insert(scid_1, dummy_htlcs_1.clone());
+               forward_htlcs.insert(scid_2, dummy_htlcs_2.clone());
+
+               let mut chanmgr_fwd_htlcs = nodes[0].node.forward_htlcs.lock().unwrap();
+               *chanmgr_fwd_htlcs = forward_htlcs.clone();
+               core::mem::drop(chanmgr_fwd_htlcs);
+
+               reload_node!(nodes[0], nodes[0].node.encode(), &[], persister, chain_monitor, deserialized_chanmgr);
+
+               let mut deserialized_fwd_htlcs = nodes[0].node.forward_htlcs.lock().unwrap();
+               for scid in [scid_1, scid_2].iter() {
+                       let deserialized_htlcs = deserialized_fwd_htlcs.remove(scid).unwrap();
+                       assert_eq!(forward_htlcs.remove(scid).unwrap(), deserialized_htlcs);
+               }
+               assert!(deserialized_fwd_htlcs.is_empty());
+               core::mem::drop(deserialized_fwd_htlcs);
+
+               expect_pending_htlcs_forwardable!(nodes[0]);
+       }
 }
 
 #[cfg(ldk_bench)]