v0.0.103

API Updates

• This release is almost entirely focused on a new API in the
  lightning-invoice crate - the InvoicePayer. InvoicePayer is a
  struct which takes a reference to a ChannelManager and a Router
  and retries payments as paths fail. It limits retries to a configurable
  number, but is not serialized to disk and may retry additional times across
  a serialization/load. In order to learn about failed payments, it must
  receive Events directly from the ChannelManager, wrapping a
  user-provided EventHandler which it provides all unhandled events to
  (#1059).
• get_route has been renamed find_route (#1059) and now takes a
  RouteParameters struct in replacement of a number of its long list of
  arguments (#1134). The Payee in the RouteParameters is stored in the
  Route object returned and provided in the RouteParameters contained in
  Event::PaymentPathFailed (#1059).
• ChannelMonitors must now be persisted after calls that provide new block
  data, prior to MonitorEvents being passed back to ChannelManager for
  processing. If you are using a ChainMonitor this is handled for you.
  The Persist API has been updated to Optionally take the
  ChannelMonitorUpdate as persistence events that result from chain data no
  longer have a corresponding update (#1108).
• routing::Score now has a payment_path_failed method which it can use to
  learn which channels often fail payments. It is automatically called by
  InvoicePayer for failed payment paths (#1144).
• The default Scorer implementation is now a type alias to a type generic
  across different clocks and supports serialization to persist scoring data
  across restarts (#1146).
• Event::PaymentSent now includes the full fee which was spent across all
  payment paths which were fulfilled or pending when the payment was fulfilled
  (#1142).
• Event::PaymentSent and Event::PaymentPathFailed now include the
  PaymentId which matches the PaymentId returned from
  ChannelManager::send_payment or InvoicePayer::pay_invoice (#1059).
• NetGraphMsgHandler now takes a Deref to the NetworkGraph, allowing for
  shared references to the graph data to make serialization and references to
  the graph data in the InvoicePayer's Router simpler (#1149).
• routing::Score::channel_penalty_msat has been updated to provide the
  NodeId of both the source and destination nodes of a channel (#1133).

Bug Fixes

• Previous versions would often disconnect peers during initial graph sync due
  to ping timeouts while processing large numbers of gossip messages. We now
  delay disconnecting peers if we receive messages from them even if it takes
  a while to receive a pong from them. Further, we avoid sending too many
  gossip messages between pings to ensure we should always receive pongs in a
  timely manner (#1137).
• If a payment was sent, creating an outbound HTLC and sending it to our
  counterparty (implying the ChannelMonitor was persisted on disk), but the
  ChannelManager was not persisted prior to shutdown/crash, no
  Event::PaymentPathFailed event was generated if the HTLC was eventually
  failed on chain. Events are now consistent irrespective of ChannelManager
  persistence or non-persistence (#1104).

Serialization Compatibility

• All above new Events/fields are ignored by prior clients. All above new
  Events/fields are not present when reading objects serialized by prior
  versions of the library.
• Payments for which a Route was generated using a previous version or for
  which the payment was originally sent by a previous version of the library
  will not be retried by an InvoicePayer.

This release was singularly focused and some contributions by third parties
were delayed.
In total, this release features 38 files changed, 4414 insertions, and 969
deletions in 71 commits from 2 authors, in alphabetical order:

• Jeffrey Czyz
• Matt Corallo

v0.0.102

API Updates

• get_route now takes a Score as an argument. Score is queried during
  the route-finding process, returning the absolute amounts which you are
  willing to pay to avoid routing over a given channel. As a default, a
  Scorer is provided which returns a constant amount, with a suggested
  default of 500 msat. This translates to a willingness to pay up to 500 msat
  in additional fees per hop in order to avoid additional hops (#1124).
• Event::PaymentPathFailed now contains a short_channel_id field which may
  be filled in with a channel that can be "blamed" for the payment failure.
  Payment retries should likely avoid the given channel for some time (#1077).
• PublicKeys in NetworkGraph have been replaced with a NodeId struct
  which contains only a simple [u8; 33], substantially improving
  NetworkGraph deserialization performance (#1107).
• ChainMonitor's HashMap of ChannelMonitors is now private, exposed via
  Chainmonitor::get_monitor and ChainMonitor::list_monitors instead
  (#1112).
• When an outbound channel is closed prior to the broadcasting of its funding
  transaction, but after you call
  ChannelManager::funding_transaction_generated, a new event type,
  Event::DiscardFunding, is generated, informing you the transaction was not
  broadcasted and that you can spend the same inputs again elsewhere (#1098).
• ChannelManager::create_channel now returns the temporary channel ID which
  may later appear in Event::ChannelClosed or ChannelDetails prior to the
  channel being funded (#1121).
• Event::PaymentSent now contains the payment hash as well as the payment
  preimage (#1062).
• ReadOnlyNetworkGraph::get_addresses now returns owned NetAddress rather
  than references. As a side-effect this method is now exposed in foreign
  language bindings (#1115).
• The Persist and ChannelMonitorUpdateErr types have moved to the
  lightning::chain::chainmonitor and lightning::chain modules,
  respectively (#1112).
• ChannelManager::send_payment now returns a PaymentId which identifies a
  payment (whether MPP or not) and can be used to retry the full payment or
  MPP parts through retry_payment (#1096). Note that doing so is currently
  not crash safe, and you may find yourself sending twice. It is recommended
  that you not use the retry_payment API until the next release.

Bug Fixes

• Due to an earlier fix for the Lightning dust inflation vulnerability tracked
  in CVE-2021-41591/CVE-2021-41592/CVE-2021-41593 in 0.0.100, we required
  counterparties to accept a dust limit slightly lower than the dust limit now
  required by other implementations. This appeared as, at least, latest lnd
  always refusing to accept channels opened by LDK clients (#1065).
• If there are multiple channels available to the same counterparty,
  get_route would only consider the channel listed last as available for
  sending (#1100).
• Persist implementations returning
  ChannelMonitorUpdateErr::TemporaryFailure from watch_channel previously
  resulted in the ChannelMonitor not being stored at all, resulting in a
  panic after monitor updating is complete (#1112).
• If payments are pending awaiting forwarding at startup, an
  Event::PendingHTLCsForwardable event will always be provided. This ensures
  user code calls ChannelManager::process_pending_htlc_fowards even if it
  shut down while awaiting the batching timer during the previous run (#1076).
• If a call to ChannelManager::send_payment failed due to lack of
  availability of funds locally, LDK would store the payment as pending
  forever, with no ability to retry or fail it, leaking memory (#1109).

Serialization Compatibility

• All above new Events/fields are ignored by prior clients. All above new
  Events/fields, except for Event::PaymentSent::payment_hash are not present
  when reading objects serialized by prior versions of the library.

In total, this release features 32 files changed, 2248 insertions, and 1483
deletions in 51 commits from 7 authors, in alphabetical order:

• 1nF0rmed
• Duncan Dean
• Elias Rohrer
• Galder Zamarreño
• Jeffrey Czyz
• Matt Corallo
• Valentine Wallace

v0.0.101

API Updates

• Custom message types are now supported directly in the PeerManager,
  allowing you to send and receive messages of any type that is not natively
  understood by LDK. This requires a new type bound on PeerManager, a
  CustomMessageHandler. IgnoringMessageHandler provides a simple default
  for this new bound for ignoring unknown messages (#1031, #1074).
• Route graph updates as a result of failed payments are no longer provided as
  MessageSendEvent::PaymentFailureNetworkUpdate but instead included in a
  new field in the Event::PaymentFailed events. Generally, this means route
  graph updates are no longer handled as a part of the PeerManager but
  instead through the new EventHandler implementation for
  NetGraphMsgHandler. To make this easy, a new parameter to
  lightning-background-processor::BackgroundProcessor::start is added, which
  contains an Optional NetGraphmsgHandler. If provided as Some, relevant
  events will be processed by the NetGraphMsgHandler prior to normal event
  handling (#1043).
• NetworkGraph is now, itself, thread-safe. Accordingly, most functions now
  take &self instead of &mut self and the graph data can be accessed
  through NetworkGraph.read_only (#1043).
• The balances available on-chain to claim after a channel has been closed are
  now exposed via ChannelMonitor::get_claimable_balances and
  ChainMonitor::get_claimable_balances. The second can be used to get
  information about all closed channels which still have on-chain balances
  associated with them. See enum variants of ln::channelmonitor::Balance and
  method documentation for the above methods for more information on the types
  of balances exposed (#1034).
• When one HTLC of a multi-path payment fails, the new field all_paths_failed
  in Event::PaymentFailed is set to false. This implies that the payment
  has not failed, but only one part. Payment resolution is only indicated by an
  Event::PaymentSent event or an Event::PaymentFailed with
  all_paths_failed set to true, which is also set for the last remaining
  part of a multi-path payment (#1053).
• To better capture the context described above, Event::PaymentFailed has
  been renamed to Event::PaymentPathFailed (#1084).
• A new event, ChannelClosed, is provided by ChannelManager when a channel
  is closed, including a reason and error message (if relevant, #997).
• lightning-invoice now considers invoices with sub-millisatoshi precision
  to be invalid, and requires millisatoshi values during construction (thus
  you must call amount_milli_satoshis instead of amount_pico_btc, #1057).
• The BaseSign interface now includes two new hooks which provide additional
  information about commitment transaction signatures and revocation secrets
  provided by our counterparty, allowing additional verification (#1039).
• The BaseSign interface now includes additional information for cooperative
  close transactions, making it easier for a signer to verify requests (#1064).
• Route has two additional helper methods to get fees and amounts (#1063).
• Txid and Transaction objects can now be deserialized from responses when
  using the HTTP client in the lightning-block-sync crate (#1037, #1061).

Bug Fixes

• Fix a panic when reading a lightning invoice with a non-recoverable
  signature. Further, restrict lightning invoice parsing to require payment
  secrets and better handle a few edge cases as required by BOLT 11 (#1057).
• Fix a panic when receiving multiple messages (such as HTLC fulfill messages)
  after a call to chain::Watch::update_channel returned
  Err(ChannelMonitorUpdateErr::TemporaryFailure) with no
  ChannelManager::channel_monitor_updated call in between (#1066).
• For multi-path payments, Event::PaymentSent is no longer generated
  multiple times, once for each independent part (#1053).
• Multi-hop route hints in invoices are now considered in the default router
  provided via get_route (#1040).
• The time peers have to respond to pings has been increased when building
  with debug assertions enabled. This avoids peer disconnections on slow hosts
  when running in debug mode (#1051).
• The timeout for the first byte of a response for requests from the
  lightning-block-sync crate has been increased to 300 seconds to better
  handle the long hangs in Bitcoin Core when it syncs to disk (#1090).

Serialization Compatibility

• Due to a bug in 0.0.100, Events written by 0.0.101 which are of a type not
  understood by 0.0.100 may lead to Err(DecodeError::InvalidValue) or corrupt
  deserialized objects in 0.100. Such Events will lead to an
  Err(DecodeError::InvalidValue) in versions prior to 0.0.100. The only such
  new event written by 0.0.101 is Event::ChannelClosed (#1087).
• Payments that were initiated in versions prior to 0.0.101 may still
  generate duplicate PaymentSent Events or may have spurious values for
  Event::PaymentPathFailed::all_paths_failed (#1053).
• The return values of ChannelMonitor::get_claimable_balances (and, thus,
  ChainMonitor::get_claimable_balances) may be spurious for channels where
  the spend of the funding transaction appeared on chain while running a
  version prior to 0.0.101. Balance information should only be relied upon
  for channels that were closed while running 0.0.101+ (#1034).
• Payments failed while running versions prior to 0.0.101 will never have a
  Some for the network_update field (#1043).

In total, this release features 67 files changed, 4980 insertions, 1888
deletions in 89 commits from 12 authors, in alphabetical order:

• Antoine Riard
• Devrandom
• Galder Zamarreño
• Giles Cope
• Jeffrey Czyz
• Joseph Goulden
• Matt Corallo
• Sergi Delgado Segura
• Tibo-lg
• Valentine Wallace
• abhik-99
• vss96

v0.0.100

API Updates

• The lightning crate can now be built in no_std mode, making it easy to
  target embedded hardware for rust users. Note that mutexes are replaced with
  no-ops for such builds (#1008, #1028).
• LDK now supports sending and receiving "keysend" payments. This includes
  modifications to lightning::util::events::Event::PaymentReceived to
  indicate the type of payment (#967).
• A new variant, lightning::util::events::Event::PaymentForwarded has been
  added which indicates a forwarded payment has been successfully claimed and
  we've received a forwarding fee (#1004).
• lightning::chain::keysinterface::KeysInterface::get_shutdown_pubkey has
  been renamed to get_shutdown_scriptpubkey, returns a script, and is now
  called on channel open only if
  lightning::util::config::ChannelConfig::commit_upfront_shutdown_pubkey is
  set (#1019).
• Closing-signed negotiation is now more configurable, with an explicit
  lightning::util::config::ChannelConfig::force_close_avoidance_max_fee_satoshis
  field allowing you to select the maximum amount you are willing to pay to
  avoid a force-closure. Further, we are now less restrictive on the fee
  placed on the closing transaction when we are not the party paying it. To
  control the feerate paid on a channel at close-time, use
  ChannelManager::close_channel_with_target_feerate instead of
  close_channel (#1011).
• lightning_background_processor::BackgroundProcessor now stops the
  background thread when dropped (#1007). It is marked #[must_use] so that
  Rust users will receive a compile-time warning when it is immediately
  dropped after construction (#1029).
• Total potential funds burn on force-close due to dust outputs is now limited
  to lightning::util::config::ChannelConfig::max_dust_htlc_exposure_msat per
  channel (#1009).
• The interval on which
  lightning::ln::peer_handler::PeerManager::timer_tick_occurred should be
  called has been reduced to once every five seconds (#1035) and
  lightning::ln::channelmanager::ChannelManager::timer_tick_occurred should
  now be called on startup in addition to once per minute (#985).
• The rust-bitcoin and bech32 dependencies have been updated to their
  respective latest versions (0.27 and 0.8, #1012).

Bug Fixes

• Fix panic when reading invoices generated by some versions of c-lightning
  (#1002 and #1003).
• Fix panic when attempting to validate a signed message of incorrect length
  (#1010).
• Do not ignore the route hints in invoices when the invoice is over 250k
  sats (#986).
• Fees are automatically updated on outbound channels to ensure commitment
  transactions are always broadcastable (#985).
• Fixes a rare case where a lightning::util::events::Event::SpendableOutputs
  event is not generated after a counterparty commitment transaction is
  confirmed in a reorg when a conflicting local commitment transaction is
  removed in the same reorg (#1022).
• Fixes a remotely-triggerable force-closure of an origin channel after an
  HTLC was forwarded over a next-hop channel and the next-hop channel was
  force-closed by our counterparty (#1025).
• Fixes a rare force-closure case when sending a payment as a channel fundee
  when overdrawing our remaining balance. Instead the send will fail (#998).
• Fixes a rare force-closure case when a payment was claimed prior to a
  peer disconnection or restart, and later failed (#977).

Serialization Compatibility

• Pending inbound keysend payments which have neither been failed nor claimed
  when serialized will result in a ChannelManager which is not readable on
  pre-0.0.100 clients (#967).
• Because
  lightning::chain::keysinterface::KeysInterface::get_shutdown_scriptpubkey
  has been updated to return a script instead of only a PublicKey,
  ChannelManagers constructed with custom KeysInterface implementations on
  0.0.100 and later versions will not be readable on previous versions.
  ChannelManagers created with 0.0.99 and prior versions will remain readable
  even after the a serialization roundtrip on 0.0.100, as long as no new
  channels are opened. Further, users using a
  lightning::chain::keysinterface::KeysManager as their KeysInterface will
  have ChannelManagers which are readable on prior versions as well (#1019).
• ChannelMonitorUpdates created by 0.0.100 and later for channels when
  lightning::util::config::ChannelConfig::commit_upfront_shutdown_pubkey is
  not set may not be readable by versions prior to 0.0.100 (#1019).
• HTLCs which were in the process of being claimed on-chain when a pre-0.0.100
  ChannelMonitor was serialized may generate PaymentForwarded events with
  spurious fee_earned_msat values. This only applies to payments which were
  unresolved at the time of the upgrade (#1004).
• 0.0.100 clients with pending Event::PaymentForwarded events at
  serialization-time will generate serialized ChannelManager objects which
  0.0.99 and earlier clients cannot read. The likelihood of this can be reduced
  by ensuring you process all pending events immediately before serialization
  (as is done by the lightning-background-processor crate, #1004).

In total, this release features 59 files changed, 5861 insertions, and 2082
deletions in 95 commits from 6 authors.

v0.0.99

API Updates

• lightning_block_sync::poll::Validate is now public, allowing you to
  implement the lightning_block_sync::poll::Poll trait without
  lightning_block_sync::poll::ChainPoller (#956).
• lightning::ln::peer_handler::PeerManager no longer requires that no calls
  are made to referencing the same SocketDescriptor after
  disconnect_socket returns. This makes the API significantly less
  deadlock-prone and simplifies SocketDescriptor implementations
  significantly. The relevant changes have been made to lightning_net_tokio
  and PeerManager documentation has been substantially rewritten (#957).
• lightning::util::message_signing's sign and verify methods now take
  secret and public keys by reference instead of value (#974).
• Substantially more information is now exposed about channels in
  ChannelDetails. See documentation for more info (#984 and #988).
• The latest best block seen is now exposed in
  ChannelManager::current_best_block and
  ChannelMonitor::current_best_block (#984).
• Feerates charged when forwarding payments over channels is now set in
  ChannelConfig::fee_base_msat when the channel is opened. For existing
  channels, the value is set to the value provided in
  ChannelManagerReadArgs::default_config::channel_options the first time the
  ChannelManager is loaded in 0.0.99 (#975).
• We now reject HTLCs which are received to be forwarded over private channels
  unless UserConfig::accept_forwards_to_priv_channels is set. Note that
  UserConfig is never serialized and must be provided via
  ChannelManagerReadArgs::default_config at each start (#975).

Bug Fixes

• We now forward gossip messages to peers instead of only relaying
  locally-generated gossip or sending gossip messages during initial sync
  (#948).
• Correctly send channel_update messages to direct peers on private channels
  (#949). Without this, a private node connected to an LDK node over a private
  channel cannot receive funds as it does not know which fees the LDK node
  will charge.
• lightning::ln::channelmanager::ChannelManager no longer expects to be
  persisted spuriously after we receive a channel_update message about any
  channel in the routing gossip (#972).
• Asynchronous ChannelMonitor updates (using the
  ChannelMonitorUpdateErr::TemporaryFailure return variant) no longer cause
  spurious HTLC forwarding failures (#954).
• Transaction provided via ChannelMonitor::transactions_confirmed
  after ChannelMonitor::best_block_updated was called for a much later
  block now trigger all relevant actions as of the later block. Previously
  some transaction broadcasts or other responses required an additional
  block be provided via ChannelMonitor::best_block_updated (#970).
• We no longer panic in rare cases when an invoice contained last-hop route
  hints which were unusable (#958).

Node Compatibility

• We now accept spurious funding_locked messages sent prior to
  channel_reestablish messages after reconnect. This is a
  known, long-standing bug in lnd
  (#966).
• We now set the first_blocknum and number_of_blocks fields in
  reply_channel_range messages to values which c-lightning versions prior to
  0.10 accepted. This avoids spurious force-closes from such nodes (#961).

Serialization Compatibility

• Due to a bug discovered in 0.0.98, if a ChannelManager is serialized on
  version 0.0.98 while an Event::PaymentSent is pending processing, the
  ChannelManager will fail to deserialize both on version 0.0.98 and later
  versions. If you have such a ChannelManager available, a simple patch will
  allow it to deserialize. Please file an issue if you need assistance (#973).

v0.0.98

0.0.98 should be considered a release candidate to the first alpha release of Rust-Lightning and the broader LDK. It represents several years of work designing and fine-tuning a flexible API for integrating lightning into any application. LDK should make it easy to build a lightning node or client which meets specific requirements that other lightning node software cannot. As lightning continues to evolve, and new use-cases for lightning develop, the API of LDK will continue to change and expand. However, starting with version 0.1, objects serialized with prior versions will be readable with the latest LDK. While Rust-Lightning is approaching the 0.1 milestone, language bindings components of LDK available at https://github.com/lightningdevkit are still of varying quality. Some are also approaching an 0.1 release, while others are still much more experimental. Please note that, at 0.0.98, using Rust-Lightning on mainnet is strongly discouraged.

v0.0.14

Merge pull request #909 from TheBlueMatt/2021-04-0.0.14

Bump versions to 0.0.14, lightning-invoice 0.5

v0.0.13

Merge pull request #835 from TheBlueMatt/2021-03-0.0.13

Bump Version to 0.0.13

v0.0.12

• Large API overhauls to make several major API surfaces much easier to work.
• C/C++ Bindings are a part of this release, however are still considered beta status. They are expected to mature as more language-specific binding work is built on top.