LDK v0.0.124: 'Papercutting Feature Requests'

• "LDK 0.0.124 is up on crates.io! Releases in other languages should follow over the coming day(s)," announced Matt Corallo.
• This release features a new crate structure, a ton of features that various users requested, a pile of BOLT 12 improvements, faster route-finding, and a handful of small-moderate bugfixes.
• In total, this release features 312 files changed, 29853 insertions, 15480 deletions in 549 commits since 0.0.123 from 26 authors.

What's new

API Updates

• rust-bitcoin has been updated to 0.32. The new bitcoin-io crate is now used for all IO traits, irrespective of the features set on LDK crates. LDK crates no longer automatically force features on dependent crates where possible, allowing different std/no-std settings between LDK and rust-bitcoin crates (e.g. to disable std on LDK to ensure system time is not accessed while using bitcoin-io's std feature). (#3063, #3239, #3249).
• A new lightning_types crate was added which contains various top-level types. Using types from lightning::ln::features or Payment{Hash,Preimage,Secret} from lightning::ln or lightning::ln::types is now deprecated. The new crate is re-exported as lightning::types (#3234, #3253).
• lightning now depends on lightning-invoice, rather than the other way around. The lightning_invoice::payment module has moved to lightning::ln::bolt11_payment and lightning_invoice::utils to lightning::ln::invoice_utils (#3234).
• Event handlers may now return errors, causing most events to be replayed immediately without blocking the background processor. See documentation on individual Events for more information on replay (#2995).
• ChannelDetails::balance_msat is deprecated in favor of ChainMonitor::get_claimable_balances and the Balance, which now contains substantially more details and more accurately calculates a node-wide balance when Balance::claimable_amount_satoshis are summed (#3212, #3247).
• ConfirmationTarget has two new variants - a MaximumFeeEstimate which can help to avoid spurious force-closes by ensuring we always accept feerates up to this value from peers as sane and a UrgentOnChainSweep, replacing OnChainSweep and only being used when the on-chain sweep is urgent (#3268).
• All ChannelMonitors are no longer persisted after each block connection, instead spreading them out over a handful of blocks to reduce load spikes. Note that this will increase the incidence of ChannelMonitors that have different best blocks on startup, requiring some additional chain replay (but only on some ChannelMonitors) on startup for Listen users (#2966).
• A new format for Rapid Gossip Sync data is now supported which contains additional node metadata and is more extensible (#3098).
• ChannelManager::send_payment_with_route is now deprecated in favor of the much easier to use Channelmanager::send_payment. Those who wish to manually select the route such payments go over should do so by matching the payment_id passed to send_payment in Router::find_route_with_id (#3224)
• lightning-transaction-sync now takes most Confirms as a generic Deref. You may need an explicit as &(dyn Confirm) to update existing code (#3101).
• HTLCs will now be forwarded over any channel with a peer, rather than only the specific channel requested by the payment sender (#3127).
• Event::PaymentFailed is now used in place of Event::InvoiceRequestFailed, holding an Option for the payment hash, which will be None when no invoice has been received (#3192).
• ChannelManager now supports intercepting and manually paying Bolt12Invoices, see UserConfig::manually_handle_bolt12_invoices (#3078).
• logger::Records now contain a PaymentHash (#2930).
• ChainMonitor no longer uses an opaque MonitorUpdateId, opting to reuse the ChannelMonitorUpdate::update_id instead. Note that you no longer have to call ChainMonitor::channel_monitor_updated for ChannelMonitorUpdateStatus::InProgress updates to a monitor that were started without a ChannelMonitorUpdate (#2957).
• NodeAnnouncementInfo is now an enum holding either a gossip message or the important fields, reducing the memory usage of NetworkGraph (#3072).
• Onion message handlers now include a message context, which allows for blinded path authentication (#3085, #3202).
• ChannelManager now supports funding with only a txid and output index, see ChannelManager::unsafe_manual_funding_transaction_generated (#3024).
• BOLT 12 invoice requests now go out over, and accept responses over, multiple paths (#3087).
• OnionMessenger now supports intercepting and re-forwarding onion messages for peers that are offline at the time of receipt when constructed with new_with_offline_peer_interception (#2973).
• Onion message handling trait methods now generally take a Responder which can be used to create a ResponseInstruction to better control how responses are sent. The ResponseInstruction can also be converted to MessageSendInstructions which can be passed to OnionMessenger's send_onion_message to respond asynchronously (#2907, #2996, #3263).
• OnionMessenger::process_pending_events_async was added (#3060).
• Blinded paths used for BOLT 12 Offer/Refunds are now compact when they expire relatively soon, making them somewhat smaller (#3011, #3080).
• ChannelManager::force_close_* now take a err msg to send to peers (#2889).
• ChannelDetails::is_public has been renamed to is_announced and ChannelHandshakeConfig::announced_channel to announce_for_forwarding to address various misconceptions about the purpose of announcement (#3257).
• BlindedPaths are now split into BlindedMessagePaths and BlindedPaymentPaths and advance_path_by_one added to each (#3182).
• BlindedPaymentPath now includes the BlindedPayInfo (#3245).
• BOLT 12 Offer/Refund builders no longer require a description, instead allowing it to be set on the builder itself (#3018).
• The {Inbound,Outbound}HTLCState{,Details} and ChannelDetails structs have moved to the ln::channel_state module (#3089).
• Event::OpenChannelRequest now contains params and is_announced (#3019).
• Peers are no longer disconnected when we force-close a channel (#3088).
• BOLT12 Offer and Refund now implement Readable (#2965).
• RecipientOnionFields is now included in Event::PaymentClaimed (#3084).
• ClosureReason::HolderForceClosed::broadcasted_latest_txn was added (#3107).
• EcdsaChannelSigner no longer needs to be Writeable and the supertrait WriteableEcdsaChannelSigner has been removed (#3059).
• CustomMessageHandler::peer_{,dis}connected were added (#3105).
• lightning_invoice::Description::as_inner() was added (#3203).
• Splice-related wire messages have been updated to the latest spec (#3129).

Bug Fixes

• channel_update messages are no longer extracted from failed payments and applied to the network graph via Event::PaymentPathFailed, preventing a node along the path from identifying the sender of a payment (#3083).
• In order to prevent senders from identifying the recipient of a BOLT 12 offer that included a blinded path, cryptographic information from blinded paths are now included in the invoice request verification (#3085, #3139, #3242).
• Routes are now length-limited based on the actual onion contents rather than a fixed value. This ensures no routes are generated that are unpayable when sending HTLCs with custom TLVs, blinded paths, or metadata (#3026, #3156).
• Unannounced LDK nodes (or ones without a network graph) will now include unannounced peers as introduction points in blinded paths. This addresses issues where test networks were not usable for BOLT 12 due to failures to find paths over private channels to LDK nodes. It will also enable creating BOLT 12 offers for nodes with no local network graph (#3132).
• If a channel partner fails to update the feerate on a channel for some time and prevailing network feerates increase, LDK will now force-close automatically to avoid being unable to claim our funds on-chain. In order to reduce false-positives, it does so by comparing the channel's fee against the minimum ConfirmationTarget::MinAllowed{,Non}AnchorChannelRemoteFee we've seen over the past day (and do not force-close if we haven't been running for a full day, #3037).
• MonitorUpdatingPersister did not read ChannelMonitorUpdates when archiving a ChannelMonitor, causing the archived ChannelMonitor to be missing some updates. Those updates were not removed from the KVStore and monitors being archived should have no pending updates as they were persisted on each new block for some time before archiving (#3276).
• CoinSelections selected for commitment transactions which did not contain a change output no longer result in broadcasting a non-standard transaction nor in under-paying the target feerate (#3285). Note that such a transaction would fail to propagate and LDK would have continued to bump the fee until a different CoinSelection is used which did contain a change output.
• invoice_errors from BOLT 12 recipients now fail payments (#3085, #3192).
• Fixed a bug which may lead to a missing Event::ChannelClosed and missing Error messages for peers when a bogus funding transaction is provided for a batch channel open (#3029).
• Fixed an overflow in RawBolt11Invoice::amount_pico_btc() reachable via Bolt11Invoice::amount_milli_satoshis(), resulting in a debug panic or bogus value for invoices with invalid values (#3032).
• In incredibly rare circumstances, when using the beta asynchronous persistence, it is possible that the preimage for an MPP claim could fail to be persisted in the ChannelMonitor for one or more MPP parts, resulting in only some of the payment's value being claimed (#3120).
• A rare race was fixed which could lead to ChannelMonitorUpdates appearing after a full ChannelMonitor persistence that already contained the same update. This could have caused a panic on startup for users of the MonitorUpdatingPersister in rare cases after a crash (#3196).
• Background Processor is now woken from ChainMonitor when new blocks appear, reducing the worst-case latency to see an Event::SpendableOutputs (#3033).
• OnionMessenger::get_update_future was added, allowing it to wake the background processor to ensure Events are processed quickly (#3194).
• CoinSelections overpaying the target feerate by more than 1% no longer leads to a debug assertion (#3285).

Backwards Compatibility

• BOLT 12 Offers created in prior versions are still valid but are at risk of deanonymization attacks allowing identification of the recipient node (#3139)
• BOLT 12 outbound payments in state RecentPaymentDetails::AwaitingInvoice will eventually time out after upgrade to 0.0.124 as any received invoice will be considered invalid (#3139).
• BOLT 12 Refunds created in prior version with non-empty Refund::paths are considered invalid by ChannelManager. Any attempts to claim them will be ignored. Refunds without blinded paths are unaffected (#3139).
• The format written by impl_writeable_tlv_based_enum[_upgradable] for tuple variants has changed, only impacting LDK-external use of the macros (#3160).
• An Event::PaymentFailed without a payment hash will deserialize to a payment hash of all-0s when downgrading (#3192).
• Event::PaymentFailed reasons may be mapped to similar reasons that were available in previous versions on downgrade (#3192).

Performance Improvements

• Route-finding is 11-23% faster (#3103, #3104, #2803, #3188, on an Intel Xeon Silver 4116 (Skylake)).
• lightning-block-sync now much better avoids lock contention during parallel requests for block data, speeding up gossip sync from multiple peers (#3197).

Node Compatibility

• 0.0.123 contained a workaround for CLN v24.02 requiring the gossip_queries feature for all peers. Since an updated CLN has now shipped which does not require this, the workaround has been reverted (#3172).
• LDK now supports BOLT 12 Offers without an explicit signing public key, allowing it to pay more compact offers generated by other nodes (#3017).
• LDK now supports BOLT 12 Offers without descriptions when no amount is present (#3018).
• A bug was fixed which might have led to LDK spuriously rejecting channel_updates that use as-yet-undefined flag bits (#3144).

GitHub Repo