pub(crate) fn opt_anchors(&self) -> bool {
self.channel_transaction_parameters.opt_anchors.is_some()
}
-}
-
-// Internal utility functions for channels
-/// Returns the value to use for `holder_max_htlc_value_in_flight_msat` as a percentage of the
-/// `channel_value_satoshis` in msat, set through
-/// [`ChannelHandshakeConfig::max_inbound_htlc_value_in_flight_percent_of_channel`]
-///
-/// The effective percentage is lower bounded by 1% and upper bounded by 100%.
-///
-/// [`ChannelHandshakeConfig::max_inbound_htlc_value_in_flight_percent_of_channel`]: crate::util::config::ChannelHandshakeConfig::max_inbound_htlc_value_in_flight_percent_of_channel
-fn get_holder_max_htlc_value_in_flight_msat(channel_value_satoshis: u64, config: &ChannelHandshakeConfig) -> u64 {
- let configured_percent = if config.max_inbound_htlc_value_in_flight_percent_of_channel < 1 {
- 1
- } else if config.max_inbound_htlc_value_in_flight_percent_of_channel > 100 {
- 100
- } else {
- config.max_inbound_htlc_value_in_flight_percent_of_channel as u64
- };
- channel_value_satoshis * 10 * configured_percent
-}
+ /// Allowed in any state (including after shutdown)
+ pub fn get_update_time_counter(&self) -> u32 {
+ self.update_time_counter
+ }
-/// Returns a minimum channel reserve value the remote needs to maintain,
-/// required by us according to the configured or default
-/// [`ChannelHandshakeConfig::their_channel_reserve_proportional_millionths`]
-///
-/// Guaranteed to return a value no larger than channel_value_satoshis
-///
-/// This is used both for outbound and inbound channels and has lower bound
-/// of `MIN_THEIR_CHAN_RESERVE_SATOSHIS`.
-pub(crate) fn get_holder_selected_channel_reserve_satoshis(channel_value_satoshis: u64, config: &UserConfig) -> u64 {
- let calculated_reserve = channel_value_satoshis.saturating_mul(config.channel_handshake_config.their_channel_reserve_proportional_millionths as u64) / 1_000_000;
- cmp::min(channel_value_satoshis, cmp::max(calculated_reserve, MIN_THEIR_CHAN_RESERVE_SATOSHIS))
-}
+ pub fn get_latest_monitor_update_id(&self) -> u64 {
+ self.latest_monitor_update_id
+ }
-/// This is for legacy reasons, present for forward-compatibility.
-/// LDK versions older than 0.0.104 don't know how read/handle values other than default
-/// from storage. Hence, we use this function to not persist default values of
-/// `holder_selected_channel_reserve_satoshis` for channels into storage.
-pub(crate) fn get_legacy_default_holder_selected_channel_reserve_satoshis(channel_value_satoshis: u64) -> u64 {
- let (q, _) = channel_value_satoshis.overflowing_div(100);
- cmp::min(channel_value_satoshis, cmp::max(q, 1000))
-}
+ pub fn should_announce(&self) -> bool {
+ self.config.announced_channel
+ }
-// TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
-// has been completed, and then turn into a Channel to get compiler-time enforcement of things like
-// calling channel_id() before we're set up or things like get_outbound_funding_signed on an
-// inbound channel.
-//
-// Holder designates channel data owned for the benefit of the user client.
-// Counterparty designates channel data owned by the another channel participant entity.
-pub(super) struct Channel<Signer: ChannelSigner> {
- pub context: ChannelContext<Signer>,
-}
+ pub fn is_outbound(&self) -> bool {
+ self.channel_transaction_parameters.is_outbound_from_holder
+ }
-#[cfg(any(test, fuzzing))]
-struct CommitmentTxInfoCached {
- fee: u64,
- total_pending_htlcs: usize,
- next_holder_htlc_id: u64,
- next_counterparty_htlc_id: u64,
- feerate: u32,
-}
+ /// Gets the fee we'd want to charge for adding an HTLC output to this Channel
+ /// Allowed in any state (including after shutdown)
+ pub fn get_outbound_forwarding_fee_base_msat(&self) -> u32 {
+ self.config.options.forwarding_fee_base_msat
+ }
-pub const DEFAULT_MAX_HTLCS: u16 = 50;
+ /// Returns true if we've ever received a message from the remote end for this Channel
+ pub fn have_received_message(&self) -> bool {
+ self.channel_state > (ChannelState::OurInitSent as u32)
+ }
-pub(crate) fn commitment_tx_base_weight(opt_anchors: bool) -> u64 {
- const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
- const COMMITMENT_TX_BASE_ANCHOR_WEIGHT: u64 = 1124;
- if opt_anchors { COMMITMENT_TX_BASE_ANCHOR_WEIGHT } else { COMMITMENT_TX_BASE_WEIGHT }
-}
+ /// Returns true if this channel is fully established and not known to be closing.
+ /// Allowed in any state (including after shutdown)
+ pub fn is_usable(&self) -> bool {
+ let mask = ChannelState::ChannelReady as u32 | BOTH_SIDES_SHUTDOWN_MASK;
+ (self.channel_state & mask) == (ChannelState::ChannelReady as u32) && !self.monitor_pending_channel_ready
+ }
-#[cfg(not(test))]
-const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
-#[cfg(test)]
-pub const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
+ /// Returns true if this channel is currently available for use. This is a superset of
+ /// is_usable() and considers things like the channel being temporarily disabled.
+ /// Allowed in any state (including after shutdown)
+ pub fn is_live(&self) -> bool {
+ self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32) == 0)
+ }
-pub const ANCHOR_OUTPUT_VALUE_SATOSHI: u64 = 330;
+ // Public utilities:
-/// The percentage of the channel value `holder_max_htlc_value_in_flight_msat` used to be set to,
-/// before this was made configurable. The percentage was made configurable in LDK 0.0.107,
-/// although LDK 0.0.104+ enabled serialization of channels with a different value set for
-/// `holder_max_htlc_value_in_flight_msat`.
-pub const MAX_IN_FLIGHT_PERCENT_LEGACY: u8 = 10;
+ pub fn channel_id(&self) -> [u8; 32] {
+ self.channel_id
+ }
-/// Maximum `funding_satoshis` value according to the BOLT #2 specification, if
-/// `option_support_large_channel` (aka wumbo channels) is not supported.
-/// It's 2^24 - 1.
-pub const MAX_FUNDING_SATOSHIS_NO_WUMBO: u64 = (1 << 24) - 1;
+ // Return the `temporary_channel_id` used during channel establishment.
+ //
+ // Will return `None` for channels created prior to LDK version 0.0.115.
+ pub fn temporary_channel_id(&self) -> Option<[u8; 32]> {
+ self.temporary_channel_id
+ }
-/// Total bitcoin supply in satoshis.
-pub const TOTAL_BITCOIN_SUPPLY_SATOSHIS: u64 = 21_000_000 * 1_0000_0000;
+ pub fn minimum_depth(&self) -> Option<u32> {
+ self.minimum_depth
+ }
-/// The maximum network dust limit for standard script formats. This currently represents the
-/// minimum output value for a P2SH output before Bitcoin Core 22 considers the entire
-/// transaction non-standard and thus refuses to relay it.
-/// We also use this as the maximum counterparty `dust_limit_satoshis` allowed, given many
-/// implementations use this value for their dust limit today.
-pub const MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS: u64 = 546;
+ /// Gets the "user_id" value passed into the construction of this channel. It has no special
+ /// meaning and exists only to allow users to have a persistent identifier of a channel.
+ pub fn get_user_id(&self) -> u128 {
+ self.user_id
+ }
-/// The maximum channel dust limit we will accept from our counterparty.
-pub const MAX_CHAN_DUST_LIMIT_SATOSHIS: u64 = MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS;
+ /// Gets the channel's type
+ pub fn get_channel_type(&self) -> &ChannelTypeFeatures {
+ &self.channel_type
+ }
-/// The dust limit is used for both the commitment transaction outputs as well as the closing
-/// transactions. For cooperative closing transactions, we require segwit outputs, though accept
-/// *any* segwit scripts, which are allowed to be up to 42 bytes in length.
-/// In order to avoid having to concern ourselves with standardness during the closing process, we
-/// simply require our counterparty to use a dust limit which will leave any segwit output
-/// standard.
-/// See <https://github.com/lightning/bolts/issues/905> for more details.
-pub const MIN_CHAN_DUST_LIMIT_SATOSHIS: u64 = 354;
+ /// Guaranteed to be Some after both ChannelReady messages have been exchanged (and, thus,
+ /// is_usable() returns true).
+ /// Allowed in any state (including after shutdown)
+ pub fn get_short_channel_id(&self) -> Option<u64> {
+ self.short_channel_id
+ }
-// Just a reasonable implementation-specific safe lower bound, higher than the dust limit.
-pub const MIN_THEIR_CHAN_RESERVE_SATOSHIS: u64 = 1000;
+ /// Allowed in any state (including after shutdown)
+ pub fn latest_inbound_scid_alias(&self) -> Option<u64> {
+ self.latest_inbound_scid_alias
+ }
-/// Used to return a simple Error back to ChannelManager. Will get converted to a
-/// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our
-/// channel_id in ChannelManager.
-pub(super) enum ChannelError {
- Ignore(String),
- Warn(String),
- Close(String),
-}
+ /// Allowed in any state (including after shutdown)
+ pub fn outbound_scid_alias(&self) -> u64 {
+ self.outbound_scid_alias
+ }
-impl fmt::Debug for ChannelError {
- fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
- match self {
- &ChannelError::Ignore(ref e) => write!(f, "Ignore : {}", e),
- &ChannelError::Warn(ref e) => write!(f, "Warn : {}", e),
- &ChannelError::Close(ref e) => write!(f, "Close : {}", e),
- }
+ /// Only allowed immediately after deserialization if get_outbound_scid_alias returns 0,
+ /// indicating we were written by LDK prior to 0.0.106 which did not set outbound SCID aliases.
+ pub fn set_outbound_scid_alias(&mut self, outbound_scid_alias: u64) {
+ assert_eq!(self.outbound_scid_alias, 0);
+ self.outbound_scid_alias = outbound_scid_alias;
}
-}
-macro_rules! secp_check {
- ($res: expr, $err: expr) => {
- match $res {
- Ok(thing) => thing,
- Err(_) => return Err(ChannelError::Close($err)),
- }
- };
-}
+ /// Returns the funding_txo we either got from our peer, or were given by
+ /// get_outbound_funding_created.
+ pub fn get_funding_txo(&self) -> Option<OutPoint> {
+ self.channel_transaction_parameters.funding_outpoint
+ }
-impl<Signer: WriteableEcdsaChannelSigner> Channel<Signer> {
- fn get_initial_channel_type(config: &UserConfig, their_features: &InitFeatures) -> ChannelTypeFeatures {
- // The default channel type (ie the first one we try) depends on whether the channel is
- // public - if it is, we just go with `only_static_remotekey` as it's the only option
- // available. If it's private, we first try `scid_privacy` as it provides better privacy
- // with no other changes, and fall back to `only_static_remotekey`.
- let mut ret = ChannelTypeFeatures::only_static_remote_key();
- if !config.channel_handshake_config.announced_channel &&
- config.channel_handshake_config.negotiate_scid_privacy &&
- their_features.supports_scid_privacy() {
- ret.set_scid_privacy_required();
- }
+ /// Returns the block hash in which our funding transaction was confirmed.
+ pub fn get_funding_tx_confirmed_in(&self) -> Option<BlockHash> {
+ self.funding_tx_confirmed_in
+ }
- // Optionally, if the user would like to negotiate the `anchors_zero_fee_htlc_tx` option, we
- // set it now. If they don't understand it, we'll fall back to our default of
- // `only_static_remotekey`.
- #[cfg(anchors)]
- { // Attributes are not allowed on if expressions on our current MSRV of 1.41.
- if config.channel_handshake_config.negotiate_anchors_zero_fee_htlc_tx &&
- their_features.supports_anchors_zero_fee_htlc_tx() {
- ret.set_anchors_zero_fee_htlc_tx_required();
- }
+ /// Returns the current number of confirmations on the funding transaction.
+ pub fn get_funding_tx_confirmations(&self, height: u32) -> u32 {
+ if self.funding_tx_confirmation_height == 0 {
+ // We either haven't seen any confirmation yet, or observed a reorg.
+ return 0;
}
- ret
+ height.checked_sub(self.funding_tx_confirmation_height).map_or(0, |c| c + 1)
}
- /// If we receive an error message, it may only be a rejection of the channel type we tried,
- /// not of our ability to open any channel at all. Thus, on error, we should first call this
- /// and see if we get a new `OpenChannel` message, otherwise the channel is failed.
- pub(crate) fn maybe_handle_error_without_close(&mut self, chain_hash: BlockHash) -> Result<msgs::OpenChannel, ()> {
- if !self.is_outbound() || self.context.channel_state != ChannelState::OurInitSent as u32 { return Err(()); }
- if self.context.channel_type == ChannelTypeFeatures::only_static_remote_key() {
- // We've exhausted our options
- return Err(());
- }
- // We support opening a few different types of channels. Try removing our additional
- // features one by one until we've either arrived at our default or the counterparty has
- // accepted one.
- //
- // Due to the order below, we may not negotiate `option_anchors_zero_fee_htlc_tx` if the
- // counterparty doesn't support `option_scid_privacy`. Since `get_initial_channel_type`
- // checks whether the counterparty supports every feature, this would only happen if the
- // counterparty is advertising the feature, but rejecting channels proposing the feature for
- // whatever reason.
- if self.context.channel_type.supports_anchors_zero_fee_htlc_tx() {
- self.context.channel_type.clear_anchors_zero_fee_htlc_tx();
- assert!(self.context.channel_transaction_parameters.opt_non_zero_fee_anchors.is_none());
- self.context.channel_transaction_parameters.opt_anchors = None;
- } else if self.context.channel_type.supports_scid_privacy() {
- self.context.channel_type.clear_scid_privacy();
- } else {
- self.context.channel_type = ChannelTypeFeatures::only_static_remote_key();
- }
- Ok(self.get_open_channel(chain_hash))
+ fn get_holder_selected_contest_delay(&self) -> u16 {
+ self.channel_transaction_parameters.holder_selected_contest_delay
}
- // Constructors:
- pub fn new_outbound<ES: Deref, SP: Deref, F: Deref>(
- fee_estimator: &LowerBoundedFeeEstimator<F>, entropy_source: &ES, signer_provider: &SP, counterparty_node_id: PublicKey, their_features: &InitFeatures,
- channel_value_satoshis: u64, push_msat: u64, user_id: u128, config: &UserConfig, current_chain_height: u32,
- outbound_scid_alias: u64
- ) -> Result<Channel<Signer>, APIError>
- where ES::Target: EntropySource,
- SP::Target: SignerProvider<Signer = Signer>,
- F::Target: FeeEstimator,
- {
- let holder_selected_contest_delay = config.channel_handshake_config.our_to_self_delay;
- let channel_keys_id = signer_provider.generate_channel_keys_id(false, channel_value_satoshis, user_id);
- let holder_signer = signer_provider.derive_channel_signer(channel_value_satoshis, channel_keys_id);
- let pubkeys = holder_signer.pubkeys().clone();
+ fn get_holder_pubkeys(&self) -> &ChannelPublicKeys {
+ &self.channel_transaction_parameters.holder_pubkeys
+ }
- if !their_features.supports_wumbo() && channel_value_satoshis > MAX_FUNDING_SATOSHIS_NO_WUMBO {
- return Err(APIError::APIMisuseError{err: format!("funding_value must not exceed {}, it was {}", MAX_FUNDING_SATOSHIS_NO_WUMBO, channel_value_satoshis)});
- }
- if channel_value_satoshis >= TOTAL_BITCOIN_SUPPLY_SATOSHIS {
- return Err(APIError::APIMisuseError{err: format!("funding_value must be smaller than the total bitcoin supply, it was {}", channel_value_satoshis)});
- }
- let channel_value_msat = channel_value_satoshis * 1000;
- if push_msat > channel_value_msat {
- return Err(APIError::APIMisuseError { err: format!("Push value ({}) was larger than channel_value ({})", push_msat, channel_value_msat) });
- }
- if holder_selected_contest_delay < BREAKDOWN_TIMEOUT {
- return Err(APIError::APIMisuseError {err: format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks", holder_selected_contest_delay)});
- }
- let holder_selected_channel_reserve_satoshis = get_holder_selected_channel_reserve_satoshis(channel_value_satoshis, config);
- if holder_selected_channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
- // Protocol level safety check in place, although it should never happen because
- // of `MIN_THEIR_CHAN_RESERVE_SATOSHIS`
- return Err(APIError::APIMisuseError { err: format!("Holder selected channel reserve below implemention limit dust_limit_satoshis {}", holder_selected_channel_reserve_satoshis) });
- }
-
- let channel_type = Self::get_initial_channel_type(&config, their_features);
- debug_assert!(channel_type.is_subset(&channelmanager::provided_channel_type_features(&config)));
+ pub fn get_counterparty_selected_contest_delay(&self) -> Option<u16> {
+ self.channel_transaction_parameters.counterparty_parameters
+ .as_ref().map(|params| params.selected_contest_delay)
+ }
- let feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Normal);
+ fn get_counterparty_pubkeys(&self) -> &ChannelPublicKeys {
+ &self.channel_transaction_parameters.counterparty_parameters.as_ref().unwrap().pubkeys
+ }
- let value_to_self_msat = channel_value_satoshis * 1000 - push_msat;
- let commitment_tx_fee = Self::commit_tx_fee_msat(feerate, MIN_AFFORDABLE_HTLC_COUNT, channel_type.requires_anchors_zero_fee_htlc_tx());
- if value_to_self_msat < commitment_tx_fee {
- return Err(APIError::APIMisuseError{ err: format!("Funding amount ({}) can't even pay fee for initial commitment transaction fee of {}.", value_to_self_msat / 1000, commitment_tx_fee / 1000) });
- }
+ /// Allowed in any state (including after shutdown)
+ pub fn get_counterparty_node_id(&self) -> PublicKey {
+ self.counterparty_node_id
+ }
- let mut secp_ctx = Secp256k1::new();
- secp_ctx.seeded_randomize(&entropy_source.get_secure_random_bytes());
+ /// Allowed in any state (including after shutdown)
+ pub fn get_holder_htlc_minimum_msat(&self) -> u64 {
+ self.holder_htlc_minimum_msat
+ }
- let shutdown_scriptpubkey = if config.channel_handshake_config.commit_upfront_shutdown_pubkey {
- match signer_provider.get_shutdown_scriptpubkey() {
- Ok(scriptpubkey) => Some(scriptpubkey),
- Err(_) => return Err(APIError::ChannelUnavailable { err: "Failed to get shutdown scriptpubkey".to_owned()}),
- }
- } else { None };
+ /// Allowed in any state (including after shutdown), but will return none before TheirInitSent
+ pub fn get_holder_htlc_maximum_msat(&self) -> Option<u64> {
+ self.get_htlc_maximum_msat(self.holder_max_htlc_value_in_flight_msat)
+ }
- if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey {
- if !shutdown_scriptpubkey.is_compatible(&their_features) {
- return Err(APIError::IncompatibleShutdownScript { script: shutdown_scriptpubkey.clone() });
- }
- }
+ /// Allowed in any state (including after shutdown)
+ pub fn get_announced_htlc_max_msat(&self) -> u64 {
+ return cmp::min(
+ // Upper bound by capacity. We make it a bit less than full capacity to prevent attempts
+ // to use full capacity. This is an effort to reduce routing failures, because in many cases
+ // channel might have been used to route very small values (either by honest users or as DoS).
+ self.channel_value_satoshis * 1000 * 9 / 10,
- let destination_script = match signer_provider.get_destination_script() {
- Ok(script) => script,
- Err(_) => return Err(APIError::ChannelUnavailable { err: "Failed to get destination script".to_owned()}),
- };
+ self.counterparty_max_htlc_value_in_flight_msat
+ );
+ }
- let temporary_channel_id = entropy_source.get_secure_random_bytes();
+ /// Allowed in any state (including after shutdown)
+ pub fn get_counterparty_htlc_minimum_msat(&self) -> u64 {
+ self.counterparty_htlc_minimum_msat
+ }
- Ok(Channel {
- context: ChannelContext {
- user_id,
+ /// Allowed in any state (including after shutdown), but will return none before TheirInitSent
+ pub fn get_counterparty_htlc_maximum_msat(&self) -> Option<u64> {
+ self.get_htlc_maximum_msat(self.counterparty_max_htlc_value_in_flight_msat)
+ }
- config: LegacyChannelConfig {
- options: config.channel_config.clone(),
- announced_channel: config.channel_handshake_config.announced_channel,
- commit_upfront_shutdown_pubkey: config.channel_handshake_config.commit_upfront_shutdown_pubkey,
- },
+ fn get_htlc_maximum_msat(&self, party_max_htlc_value_in_flight_msat: u64) -> Option<u64> {
+ self.counterparty_selected_channel_reserve_satoshis.map(|counterparty_reserve| {
+ let holder_reserve = self.holder_selected_channel_reserve_satoshis;
+ cmp::min(
+ (self.channel_value_satoshis - counterparty_reserve - holder_reserve) * 1000,
+ party_max_htlc_value_in_flight_msat
+ )
+ })
+ }
- prev_config: None,
+ pub fn get_value_satoshis(&self) -> u64 {
+ self.channel_value_satoshis
+ }
- inbound_handshake_limits_override: Some(config.channel_handshake_limits.clone()),
+ pub fn get_fee_proportional_millionths(&self) -> u32 {
+ self.config.options.forwarding_fee_proportional_millionths
+ }
- channel_id: temporary_channel_id,
- temporary_channel_id: Some(temporary_channel_id),
- channel_state: ChannelState::OurInitSent as u32,
- announcement_sigs_state: AnnouncementSigsState::NotSent,
- secp_ctx,
- channel_value_satoshis,
+ pub fn get_cltv_expiry_delta(&self) -> u16 {
+ cmp::max(self.config.options.cltv_expiry_delta, MIN_CLTV_EXPIRY_DELTA)
+ }
- latest_monitor_update_id: 0,
+ pub fn get_max_dust_htlc_exposure_msat(&self) -> u64 {
+ self.config.options.max_dust_htlc_exposure_msat
+ }
- holder_signer,
- shutdown_scriptpubkey,
- destination_script,
+ /// Returns the previous [`ChannelConfig`] applied to this channel, if any.
+ pub fn prev_config(&self) -> Option<ChannelConfig> {
+ self.prev_config.map(|prev_config| prev_config.0)
+ }
- cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
- cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
- value_to_self_msat,
+ // Checks whether we should emit a `ChannelPending` event.
+ pub(crate) fn should_emit_channel_pending_event(&mut self) -> bool {
+ self.is_funding_initiated() && !self.channel_pending_event_emitted
+ }
- pending_inbound_htlcs: Vec::new(),
- pending_outbound_htlcs: Vec::new(),
- holding_cell_htlc_updates: Vec::new(),
- pending_update_fee: None,
- holding_cell_update_fee: None,
- next_holder_htlc_id: 0,
- next_counterparty_htlc_id: 0,
- update_time_counter: 1,
+ // Returns whether we already emitted a `ChannelPending` event.
+ pub(crate) fn channel_pending_event_emitted(&self) -> bool {
+ self.channel_pending_event_emitted
+ }
- resend_order: RAACommitmentOrder::CommitmentFirst,
+ // Remembers that we already emitted a `ChannelPending` event.
+ pub(crate) fn set_channel_pending_event_emitted(&mut self) {
+ self.channel_pending_event_emitted = true;
+ }
- monitor_pending_channel_ready: false,
- monitor_pending_revoke_and_ack: false,
- monitor_pending_commitment_signed: false,
- monitor_pending_forwards: Vec::new(),
- monitor_pending_failures: Vec::new(),
- monitor_pending_finalized_fulfills: Vec::new(),
+ // Checks whether we should emit a `ChannelReady` event.
+ pub(crate) fn should_emit_channel_ready_event(&mut self) -> bool {
+ self.is_usable() && !self.channel_ready_event_emitted
+ }
- #[cfg(debug_assertions)]
- holder_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
- #[cfg(debug_assertions)]
- counterparty_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
+ // Remembers that we already emitted a `ChannelReady` event.
+ pub(crate) fn set_channel_ready_event_emitted(&mut self) {
+ self.channel_ready_event_emitted = true;
+ }
- last_sent_closing_fee: None,
- pending_counterparty_closing_signed: None,
- closing_fee_limits: None,
- target_closing_feerate_sats_per_kw: None,
+ /// Tracks the number of ticks elapsed since the previous [`ChannelConfig`] was updated. Once
+ /// [`EXPIRE_PREV_CONFIG_TICKS`] is reached, the previous config is considered expired and will
+ /// no longer be considered when forwarding HTLCs.
+ pub fn maybe_expire_prev_config(&mut self) {
+ if self.prev_config.is_none() {
+ return;
+ }
+ let prev_config = self.prev_config.as_mut().unwrap();
+ prev_config.1 += 1;
+ if prev_config.1 == EXPIRE_PREV_CONFIG_TICKS {
+ self.prev_config = None;
+ }
+ }
- inbound_awaiting_accept: false,
+ /// Returns the current [`ChannelConfig`] applied to the channel.
+ pub fn config(&self) -> ChannelConfig {
+ self.config.options
+ }
- funding_tx_confirmed_in: None,
- funding_tx_confirmation_height: 0,
- short_channel_id: None,
- channel_creation_height: current_chain_height,
+ /// Updates the channel's config. A bool is returned indicating whether the config update
+ /// applied resulted in a new ChannelUpdate message.
+ pub fn update_config(&mut self, config: &ChannelConfig) -> bool {
+ let did_channel_update =
+ self.config.options.forwarding_fee_proportional_millionths != config.forwarding_fee_proportional_millionths ||
+ self.config.options.forwarding_fee_base_msat != config.forwarding_fee_base_msat ||
+ self.config.options.cltv_expiry_delta != config.cltv_expiry_delta;
+ if did_channel_update {
+ self.prev_config = Some((self.config.options, 0));
+ // Update the counter, which backs the ChannelUpdate timestamp, to allow the relay
+ // policy change to propagate throughout the network.
+ self.update_time_counter += 1;
+ }
+ self.config.options = *config;
+ did_channel_update
+ }
- feerate_per_kw: feerate,
- counterparty_dust_limit_satoshis: 0,
- holder_dust_limit_satoshis: MIN_CHAN_DUST_LIMIT_SATOSHIS,
- counterparty_max_htlc_value_in_flight_msat: 0,
- holder_max_htlc_value_in_flight_msat: get_holder_max_htlc_value_in_flight_msat(channel_value_satoshis, &config.channel_handshake_config),
- counterparty_selected_channel_reserve_satoshis: None, // Filled in in accept_channel
- holder_selected_channel_reserve_satoshis,
- counterparty_htlc_minimum_msat: 0,
- holder_htlc_minimum_msat: if config.channel_handshake_config.our_htlc_minimum_msat == 0 { 1 } else { config.channel_handshake_config.our_htlc_minimum_msat },
- counterparty_max_accepted_htlcs: 0,
- holder_max_accepted_htlcs: cmp::min(config.channel_handshake_config.our_max_accepted_htlcs, MAX_HTLCS),
- minimum_depth: None, // Filled in in accept_channel
+ /// Returns true if funding_created was sent/received.
+ pub fn is_funding_initiated(&self) -> bool {
+ self.channel_state >= ChannelState::FundingSent as u32
+ }
- counterparty_forwarding_info: None,
+ /// Transaction nomenclature is somewhat confusing here as there are many different cases - a
+ /// transaction is referred to as "a's transaction" implying that a will be able to broadcast
+ /// the transaction. Thus, b will generally be sending a signature over such a transaction to
+ /// a, and a can revoke the transaction by providing b the relevant per_commitment_secret. As
+ /// such, a transaction is generally the result of b increasing the amount paid to a (or adding
+ /// an HTLC to a).
+ /// @local is used only to convert relevant internal structures which refer to remote vs local
+ /// to decide value of outputs and direction of HTLCs.
+ /// @generated_by_local is used to determine *which* HTLCs to include - noting that the HTLC
+ /// state may indicate that one peer has informed the other that they'd like to add an HTLC but
+ /// have not yet committed it. Such HTLCs will only be included in transactions which are being
+ /// generated by the peer which proposed adding the HTLCs, and thus we need to understand both
+ /// which peer generated this transaction and "to whom" this transaction flows.
+ #[inline]
+ fn build_commitment_transaction<L: Deref>(&self, commitment_number: u64, keys: &TxCreationKeys, local: bool, generated_by_local: bool, logger: &L) -> CommitmentStats
+ where L::Target: Logger
+ {
+ let mut included_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::new();
+ let num_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
+ let mut included_non_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(num_htlcs);
- channel_transaction_parameters: ChannelTransactionParameters {
- holder_pubkeys: pubkeys,
- holder_selected_contest_delay: config.channel_handshake_config.our_to_self_delay,
- is_outbound_from_holder: true,
- counterparty_parameters: None,
- funding_outpoint: None,
- opt_anchors: if channel_type.requires_anchors_zero_fee_htlc_tx() { Some(()) } else { None },
- opt_non_zero_fee_anchors: None
- },
- funding_transaction: None,
+ let broadcaster_dust_limit_satoshis = if local { self.holder_dust_limit_satoshis } else { self.counterparty_dust_limit_satoshis };
+ let mut remote_htlc_total_msat = 0;
+ let mut local_htlc_total_msat = 0;
+ let mut value_to_self_msat_offset = 0;
- counterparty_cur_commitment_point: None,
- counterparty_prev_commitment_point: None,
- counterparty_node_id,
+ let mut feerate_per_kw = self.feerate_per_kw;
+ if let Some((feerate, update_state)) = self.pending_update_fee {
+ if match update_state {
+ // Note that these match the inclusion criteria when scanning
+ // pending_inbound_htlcs below.
+ FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); !generated_by_local },
+ FeeUpdateState::AwaitingRemoteRevokeToAnnounce => { debug_assert!(!self.is_outbound()); !generated_by_local },
+ FeeUpdateState::Outbound => { assert!(self.is_outbound()); generated_by_local },
+ } {
+ feerate_per_kw = feerate;
+ }
+ }
- counterparty_shutdown_scriptpubkey: None,
+ log_trace!(logger, "Building commitment transaction number {} (really {} xor {}) for channel {} for {}, generated by {} with fee {}...",
+ commitment_number, (INITIAL_COMMITMENT_NUMBER - commitment_number),
+ get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound()),
+ log_bytes!(self.channel_id), if local { "us" } else { "remote" }, if generated_by_local { "us" } else { "remote" }, feerate_per_kw);
- commitment_secrets: CounterpartyCommitmentSecrets::new(),
+ macro_rules! get_htlc_in_commitment {
+ ($htlc: expr, $offered: expr) => {
+ HTLCOutputInCommitment {
+ offered: $offered,
+ amount_msat: $htlc.amount_msat,
+ cltv_expiry: $htlc.cltv_expiry,
+ payment_hash: $htlc.payment_hash,
+ transaction_output_index: None
+ }
+ }
+ }
- channel_update_status: ChannelUpdateStatus::Enabled,
- closing_signed_in_flight: false,
-
- announcement_sigs: None,
-
- #[cfg(any(test, fuzzing))]
- next_local_commitment_tx_fee_info_cached: Mutex::new(None),
- #[cfg(any(test, fuzzing))]
- next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
+ macro_rules! add_htlc_output {
+ ($htlc: expr, $outbound: expr, $source: expr, $state_name: expr) => {
+ if $outbound == local { // "offered HTLC output"
+ let htlc_in_tx = get_htlc_in_commitment!($htlc, true);
+ let htlc_tx_fee = if self.opt_anchors() {
+ 0
+ } else {
+ feerate_per_kw as u64 * htlc_timeout_tx_weight(false) / 1000
+ };
+ if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + htlc_tx_fee {
+ log_trace!(logger, " ...including {} {} HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
+ included_non_dust_htlcs.push((htlc_in_tx, $source));
+ } else {
+ log_trace!(logger, " ...including {} {} dust HTLC {} (hash {}) with value {} due to dust limit", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
+ included_dust_htlcs.push((htlc_in_tx, $source));
+ }
+ } else {
+ let htlc_in_tx = get_htlc_in_commitment!($htlc, false);
+ let htlc_tx_fee = if self.opt_anchors() {
+ 0
+ } else {
+ feerate_per_kw as u64 * htlc_success_tx_weight(false) / 1000
+ };
+ if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + htlc_tx_fee {
+ log_trace!(logger, " ...including {} {} HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
+ included_non_dust_htlcs.push((htlc_in_tx, $source));
+ } else {
+ log_trace!(logger, " ...including {} {} dust HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
+ included_dust_htlcs.push((htlc_in_tx, $source));
+ }
+ }
+ }
+ }
- workaround_lnd_bug_4006: None,
- sent_message_awaiting_response: None,
+ for ref htlc in self.pending_inbound_htlcs.iter() {
+ let (include, state_name) = match htlc.state {
+ InboundHTLCState::RemoteAnnounced(_) => (!generated_by_local, "RemoteAnnounced"),
+ InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) => (!generated_by_local, "AwaitingRemoteRevokeToAnnounce"),
+ InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => (true, "AwaitingAnnouncedRemoteRevoke"),
+ InboundHTLCState::Committed => (true, "Committed"),
+ InboundHTLCState::LocalRemoved(_) => (!generated_by_local, "LocalRemoved"),
+ };
- latest_inbound_scid_alias: None,
- outbound_scid_alias,
+ if include {
+ add_htlc_output!(htlc, false, None, state_name);
+ remote_htlc_total_msat += htlc.amount_msat;
+ } else {
+ log_trace!(logger, " ...not including inbound HTLC {} (hash {}) with value {} due to state ({})", htlc.htlc_id, log_bytes!(htlc.payment_hash.0), htlc.amount_msat, state_name);
+ match &htlc.state {
+ &InboundHTLCState::LocalRemoved(ref reason) => {
+ if generated_by_local {
+ if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
+ value_to_self_msat_offset += htlc.amount_msat as i64;
+ }
+ }
+ },
+ _ => {},
+ }
+ }
+ }
- channel_pending_event_emitted: false,
- channel_ready_event_emitted: false,
+ let mut preimages: Vec<PaymentPreimage> = Vec::new();
- #[cfg(any(test, fuzzing))]
- historical_inbound_htlc_fulfills: HashSet::new(),
+ for ref htlc in self.pending_outbound_htlcs.iter() {
+ let (include, state_name) = match htlc.state {
+ OutboundHTLCState::LocalAnnounced(_) => (generated_by_local, "LocalAnnounced"),
+ OutboundHTLCState::Committed => (true, "Committed"),
+ OutboundHTLCState::RemoteRemoved(_) => (generated_by_local, "RemoteRemoved"),
+ OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) => (generated_by_local, "AwaitingRemoteRevokeToRemove"),
+ OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) => (false, "AwaitingRemovedRemoteRevoke"),
+ };
- channel_type,
- channel_keys_id,
+ let preimage_opt = match htlc.state {
+ OutboundHTLCState::RemoteRemoved(OutboundHTLCOutcome::Success(p)) => p,
+ OutboundHTLCState::AwaitingRemoteRevokeToRemove(OutboundHTLCOutcome::Success(p)) => p,
+ OutboundHTLCState::AwaitingRemovedRemoteRevoke(OutboundHTLCOutcome::Success(p)) => p,
+ _ => None,
+ };
- pending_monitor_updates: Vec::new(),
+ if let Some(preimage) = preimage_opt {
+ preimages.push(preimage);
}
- })
- }
- fn check_remote_fee<F: Deref, L: Deref>(fee_estimator: &LowerBoundedFeeEstimator<F>,
- feerate_per_kw: u32, cur_feerate_per_kw: Option<u32>, logger: &L)
- -> Result<(), ChannelError> where F::Target: FeeEstimator, L::Target: Logger,
- {
- // We only bound the fee updates on the upper side to prevent completely absurd feerates,
- // always accepting up to 25 sat/vByte or 10x our fee estimator's "High Priority" fee.
- // We generally don't care too much if they set the feerate to something very high, but it
- // could result in the channel being useless due to everything being dust.
- let upper_limit = cmp::max(250 * 25,
- fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64 * 10);
- if feerate_per_kw as u64 > upper_limit {
- return Err(ChannelError::Close(format!("Peer's feerate much too high. Actual: {}. Our expected upper limit: {}", feerate_per_kw, upper_limit)));
- }
- let lower_limit = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Background);
- // Some fee estimators round up to the next full sat/vbyte (ie 250 sats per kw), causing
- // occasional issues with feerate disagreements between an initiator that wants a feerate
- // of 1.1 sat/vbyte and a receiver that wants 1.1 rounded up to 2. Thus, we always add 250
- // sat/kw before the comparison here.
- if feerate_per_kw + 250 < lower_limit {
- if let Some(cur_feerate) = cur_feerate_per_kw {
- if feerate_per_kw > cur_feerate {
- log_warn!(logger,
- "Accepting feerate that may prevent us from closing this channel because it's higher than what we have now. Had {} s/kW, now {} s/kW.",
- cur_feerate, feerate_per_kw);
- return Ok(());
+ if include {
+ add_htlc_output!(htlc, true, Some(&htlc.source), state_name);
+ local_htlc_total_msat += htlc.amount_msat;
+ } else {
+ log_trace!(logger, " ...not including outbound HTLC {} (hash {}) with value {} due to state ({})", htlc.htlc_id, log_bytes!(htlc.payment_hash.0), htlc.amount_msat, state_name);
+ match htlc.state {
+ OutboundHTLCState::AwaitingRemoteRevokeToRemove(OutboundHTLCOutcome::Success(_))|OutboundHTLCState::AwaitingRemovedRemoteRevoke(OutboundHTLCOutcome::Success(_)) => {
+ value_to_self_msat_offset -= htlc.amount_msat as i64;
+ },
+ OutboundHTLCState::RemoteRemoved(OutboundHTLCOutcome::Success(_)) => {
+ if !generated_by_local {
+ value_to_self_msat_offset -= htlc.amount_msat as i64;
+ }
+ },
+ _ => {},
}
}
- return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {} (- 250)", feerate_per_kw, lower_limit)));
}
- Ok(())
- }
- /// Creates a new channel from a remote sides' request for one.
- /// Assumes chain_hash has already been checked and corresponds with what we expect!
- pub fn new_from_req<ES: Deref, SP: Deref, F: Deref, L: Deref>(
- fee_estimator: &LowerBoundedFeeEstimator<F>, entropy_source: &ES, signer_provider: &SP,
- counterparty_node_id: PublicKey, our_supported_features: &ChannelTypeFeatures,
- their_features: &InitFeatures, msg: &msgs::OpenChannel, user_id: u128, config: &UserConfig,
- current_chain_height: u32, logger: &L, outbound_scid_alias: u64
- ) -> Result<Channel<Signer>, ChannelError>
- where ES::Target: EntropySource,
- SP::Target: SignerProvider<Signer = Signer>,
- F::Target: FeeEstimator,
- L::Target: Logger,
- {
- let announced_channel = if (msg.channel_flags & 1) == 1 { true } else { false };
+ let mut value_to_self_msat: i64 = (self.value_to_self_msat - local_htlc_total_msat) as i64 + value_to_self_msat_offset;
+ assert!(value_to_self_msat >= 0);
+ // Note that in case they have several just-awaiting-last-RAA fulfills in-progress (ie
+ // AwaitingRemoteRevokeToRemove or AwaitingRemovedRemoteRevoke) we may have allowed them to
+ // "violate" their reserve value by couting those against it. Thus, we have to convert
+ // everything to i64 before subtracting as otherwise we can overflow.
+ let mut value_to_remote_msat: i64 = (self.channel_value_satoshis * 1000) as i64 - (self.value_to_self_msat as i64) - (remote_htlc_total_msat as i64) - value_to_self_msat_offset;
+ assert!(value_to_remote_msat >= 0);
- // First check the channel type is known, failing before we do anything else if we don't
- // support this channel type.
- let channel_type = if let Some(channel_type) = &msg.channel_type {
- if channel_type.supports_any_optional_bits() {
- return Err(ChannelError::Close("Channel Type field contained optional bits - this is not allowed".to_owned()));
- }
+ #[cfg(debug_assertions)]
+ {
+ // Make sure that the to_self/to_remote is always either past the appropriate
+ // channel_reserve *or* it is making progress towards it.
+ let mut broadcaster_max_commitment_tx_output = if generated_by_local {
+ self.holder_max_commitment_tx_output.lock().unwrap()
+ } else {
+ self.counterparty_max_commitment_tx_output.lock().unwrap()
+ };
+ debug_assert!(broadcaster_max_commitment_tx_output.0 <= value_to_self_msat as u64 || value_to_self_msat / 1000 >= self.counterparty_selected_channel_reserve_satoshis.unwrap() as i64);
+ broadcaster_max_commitment_tx_output.0 = cmp::max(broadcaster_max_commitment_tx_output.0, value_to_self_msat as u64);
+ debug_assert!(broadcaster_max_commitment_tx_output.1 <= value_to_remote_msat as u64 || value_to_remote_msat / 1000 >= self.holder_selected_channel_reserve_satoshis as i64);
+ broadcaster_max_commitment_tx_output.1 = cmp::max(broadcaster_max_commitment_tx_output.1, value_to_remote_msat as u64);
+ }
- // We only support the channel types defined by the `ChannelManager` in
- // `provided_channel_type_features`. The channel type must always support
- // `static_remote_key`.
- if !channel_type.requires_static_remote_key() {
- return Err(ChannelError::Close("Channel Type was not understood - we require static remote key".to_owned()));
- }
- // Make sure we support all of the features behind the channel type.
- if !channel_type.is_subset(our_supported_features) {
- return Err(ChannelError::Close("Channel Type contains unsupported features".to_owned()));
- }
- if channel_type.requires_scid_privacy() && announced_channel {
- return Err(ChannelError::Close("SCID Alias/Privacy Channel Type cannot be set on a public channel".to_owned()));
- }
- channel_type.clone()
+ let total_fee_sat = commit_tx_fee_sat(feerate_per_kw, included_non_dust_htlcs.len(), self.channel_transaction_parameters.opt_anchors.is_some());
+ let anchors_val = if self.channel_transaction_parameters.opt_anchors.is_some() { ANCHOR_OUTPUT_VALUE_SATOSHI * 2 } else { 0 } as i64;
+ let (value_to_self, value_to_remote) = if self.is_outbound() {
+ (value_to_self_msat / 1000 - anchors_val - total_fee_sat as i64, value_to_remote_msat / 1000)
} else {
- let channel_type = ChannelTypeFeatures::from_init(&their_features);
- if channel_type != ChannelTypeFeatures::only_static_remote_key() {
- return Err(ChannelError::Close("Only static_remote_key is supported for non-negotiated channel types".to_owned()));
- }
- channel_type
+ (value_to_self_msat / 1000, value_to_remote_msat / 1000 - anchors_val - total_fee_sat as i64)
};
- let opt_anchors = channel_type.supports_anchors_zero_fee_htlc_tx();
- let channel_keys_id = signer_provider.generate_channel_keys_id(true, msg.funding_satoshis, user_id);
- let holder_signer = signer_provider.derive_channel_signer(msg.funding_satoshis, channel_keys_id);
- let pubkeys = holder_signer.pubkeys().clone();
- let counterparty_pubkeys = ChannelPublicKeys {
- funding_pubkey: msg.funding_pubkey,
- revocation_basepoint: msg.revocation_basepoint,
- payment_point: msg.payment_point,
- delayed_payment_basepoint: msg.delayed_payment_basepoint,
- htlc_basepoint: msg.htlc_basepoint
+ let mut value_to_a = if local { value_to_self } else { value_to_remote };
+ let mut value_to_b = if local { value_to_remote } else { value_to_self };
+ let (funding_pubkey_a, funding_pubkey_b) = if local {
+ (self.get_holder_pubkeys().funding_pubkey, self.get_counterparty_pubkeys().funding_pubkey)
+ } else {
+ (self.get_counterparty_pubkeys().funding_pubkey, self.get_holder_pubkeys().funding_pubkey)
};
- if config.channel_handshake_config.our_to_self_delay < BREAKDOWN_TIMEOUT {
- return Err(ChannelError::Close(format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks. It must be greater than {}", config.channel_handshake_config.our_to_self_delay, BREAKDOWN_TIMEOUT)));
+ if value_to_a >= (broadcaster_dust_limit_satoshis as i64) {
+ log_trace!(logger, " ...including {} output with value {}", if local { "to_local" } else { "to_remote" }, value_to_a);
+ } else {
+ value_to_a = 0;
}
- // Check sanity of message fields:
- if msg.funding_satoshis > config.channel_handshake_limits.max_funding_satoshis {
- return Err(ChannelError::Close(format!("Per our config, funding must be at most {}. It was {}", config.channel_handshake_limits.max_funding_satoshis, msg.funding_satoshis)));
- }
- if msg.funding_satoshis >= TOTAL_BITCOIN_SUPPLY_SATOSHIS {
- return Err(ChannelError::Close(format!("Funding must be smaller than the total bitcoin supply. It was {}", msg.funding_satoshis)));
- }
- if msg.channel_reserve_satoshis > msg.funding_satoshis {
- return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must be not greater than funding_satoshis: {}", msg.channel_reserve_satoshis, msg.funding_satoshis)));
- }
- let full_channel_value_msat = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
- if msg.push_msat > full_channel_value_msat {
- return Err(ChannelError::Close(format!("push_msat {} was larger than channel amount minus reserve ({})", msg.push_msat, full_channel_value_msat)));
- }
- if msg.dust_limit_satoshis > msg.funding_satoshis {
- return Err(ChannelError::Close(format!("dust_limit_satoshis {} was larger than funding_satoshis {}. Peer never wants payout outputs?", msg.dust_limit_satoshis, msg.funding_satoshis)));
- }
- if msg.htlc_minimum_msat >= full_channel_value_msat {
- return Err(ChannelError::Close(format!("Minimum htlc value ({}) was larger than full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
+ if value_to_b >= (broadcaster_dust_limit_satoshis as i64) {
+ log_trace!(logger, " ...including {} output with value {}", if local { "to_remote" } else { "to_local" }, value_to_b);
+ } else {
+ value_to_b = 0;
}
- Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw, None, logger)?;
- let max_counterparty_selected_contest_delay = u16::min(config.channel_handshake_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
- if msg.to_self_delay > max_counterparty_selected_contest_delay {
- return Err(ChannelError::Close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_counterparty_selected_contest_delay, msg.to_self_delay)));
- }
- if msg.max_accepted_htlcs < 1 {
- return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
- }
- if msg.max_accepted_htlcs > MAX_HTLCS {
- return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
- }
+ let num_nondust_htlcs = included_non_dust_htlcs.len();
- // Now check against optional parameters as set by config...
- if msg.funding_satoshis < config.channel_handshake_limits.min_funding_satoshis {
- return Err(ChannelError::Close(format!("Funding satoshis ({}) is less than the user specified limit ({})", msg.funding_satoshis, config.channel_handshake_limits.min_funding_satoshis)));
- }
- if msg.htlc_minimum_msat > config.channel_handshake_limits.max_htlc_minimum_msat {
- return Err(ChannelError::Close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.htlc_minimum_msat, config.channel_handshake_limits.max_htlc_minimum_msat)));
- }
- if msg.max_htlc_value_in_flight_msat < config.channel_handshake_limits.min_max_htlc_value_in_flight_msat {
- return Err(ChannelError::Close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.max_htlc_value_in_flight_msat, config.channel_handshake_limits.min_max_htlc_value_in_flight_msat)));
- }
- if msg.channel_reserve_satoshis > config.channel_handshake_limits.max_channel_reserve_satoshis {
- return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, config.channel_handshake_limits.max_channel_reserve_satoshis)));
- }
- if msg.max_accepted_htlcs < config.channel_handshake_limits.min_max_accepted_htlcs {
- return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, config.channel_handshake_limits.min_max_accepted_htlcs)));
- }
- if msg.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
- return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
- }
- if msg.dust_limit_satoshis > MAX_CHAN_DUST_LIMIT_SATOSHIS {
- return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
- }
+ let channel_parameters =
+ if local { self.channel_transaction_parameters.as_holder_broadcastable() }
+ else { self.channel_transaction_parameters.as_counterparty_broadcastable() };
+ let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(commitment_number,
+ value_to_a as u64,
+ value_to_b as u64,
+ self.channel_transaction_parameters.opt_anchors.is_some(),
+ funding_pubkey_a,
+ funding_pubkey_b,
+ keys.clone(),
+ feerate_per_kw,
+ &mut included_non_dust_htlcs,
+ &channel_parameters
+ );
+ let mut htlcs_included = included_non_dust_htlcs;
+ // The unwrap is safe, because all non-dust HTLCs have been assigned an output index
+ htlcs_included.sort_unstable_by_key(|h| h.0.transaction_output_index.unwrap());
+ htlcs_included.append(&mut included_dust_htlcs);
- // Convert things into internal flags and prep our state:
+ // For the stats, trimmed-to-0 the value in msats accordingly
+ value_to_self_msat = if (value_to_self_msat * 1000) < broadcaster_dust_limit_satoshis as i64 { 0 } else { value_to_self_msat };
+ value_to_remote_msat = if (value_to_remote_msat * 1000) < broadcaster_dust_limit_satoshis as i64 { 0 } else { value_to_remote_msat };
- if config.channel_handshake_limits.force_announced_channel_preference {
- if config.channel_handshake_config.announced_channel != announced_channel {
- return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours".to_owned()));
- }
+ CommitmentStats {
+ tx,
+ feerate_per_kw,
+ total_fee_sat,
+ num_nondust_htlcs,
+ htlcs_included,
+ local_balance_msat: value_to_self_msat as u64,
+ remote_balance_msat: value_to_remote_msat as u64,
+ preimages
}
+ }
- let holder_selected_channel_reserve_satoshis = get_holder_selected_channel_reserve_satoshis(msg.funding_satoshis, config);
- if holder_selected_channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
- // Protocol level safety check in place, although it should never happen because
- // of `MIN_THEIR_CHAN_RESERVE_SATOSHIS`
- return Err(ChannelError::Close(format!("Suitable channel reserve not found. remote_channel_reserve was ({}). dust_limit_satoshis is ({}).", holder_selected_channel_reserve_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
- }
- if holder_selected_channel_reserve_satoshis * 1000 >= full_channel_value_msat {
- return Err(ChannelError::Close(format!("Suitable channel reserve not found. remote_channel_reserve was ({})msats. Channel value is ({} - {})msats.", holder_selected_channel_reserve_satoshis * 1000, full_channel_value_msat, msg.push_msat)));
- }
- if msg.channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
- log_debug!(logger, "channel_reserve_satoshis ({}) is smaller than our dust limit ({}). We can broadcast stale states without any risk, implying this channel is very insecure for our counterparty.",
- msg.channel_reserve_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS);
+ #[inline]
+ /// Creates a set of keys for build_commitment_transaction to generate a transaction which our
+ /// counterparty will sign (ie DO NOT send signatures over a transaction created by this to
+ /// our counterparty!)
+ /// The result is a transaction which we can revoke broadcastership of (ie a "local" transaction)
+ /// TODO Some magic rust shit to compile-time check this?
+ fn build_holder_transaction_keys(&self, commitment_number: u64) -> TxCreationKeys {
+ let per_commitment_point = self.holder_signer.get_per_commitment_point(commitment_number, &self.secp_ctx);
+ let delayed_payment_base = &self.get_holder_pubkeys().delayed_payment_basepoint;
+ let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
+ let counterparty_pubkeys = self.get_counterparty_pubkeys();
+
+ TxCreationKeys::derive_new(&self.secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint)
+ }
+
+ #[inline]
+ /// Creates a set of keys for build_commitment_transaction to generate a transaction which we
+ /// will sign and send to our counterparty.
+ /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
+ fn build_remote_transaction_keys(&self) -> TxCreationKeys {
+ //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
+ //may see payments to it!
+ let revocation_basepoint = &self.get_holder_pubkeys().revocation_basepoint;
+ let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
+ let counterparty_pubkeys = self.get_counterparty_pubkeys();
+
+ TxCreationKeys::derive_new(&self.secp_ctx, &self.counterparty_cur_commitment_point.unwrap(), &counterparty_pubkeys.delayed_payment_basepoint, &counterparty_pubkeys.htlc_basepoint, revocation_basepoint, htlc_basepoint)
+ }
+
+ /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
+ /// pays to get_funding_redeemscript().to_v0_p2wsh()).
+ /// Panics if called before accept_channel/new_from_req
+ pub fn get_funding_redeemscript(&self) -> Script {
+ make_funding_redeemscript(&self.get_holder_pubkeys().funding_pubkey, self.counterparty_funding_pubkey())
+ }
+
+ fn counterparty_funding_pubkey(&self) -> &PublicKey {
+ &self.get_counterparty_pubkeys().funding_pubkey
+ }
+
+ pub fn get_feerate_sat_per_1000_weight(&self) -> u32 {
+ self.feerate_per_kw
+ }
+
+ pub fn get_dust_buffer_feerate(&self, outbound_feerate_update: Option<u32>) -> u32 {
+ // When calculating our exposure to dust HTLCs, we assume that the channel feerate
+ // may, at any point, increase by at least 10 sat/vB (i.e 2530 sat/kWU) or 25%,
+ // whichever is higher. This ensures that we aren't suddenly exposed to significantly
+ // more dust balance if the feerate increases when we have several HTLCs pending
+ // which are near the dust limit.
+ let mut feerate_per_kw = self.feerate_per_kw;
+ // If there's a pending update fee, use it to ensure we aren't under-estimating
+ // potential feerate updates coming soon.
+ if let Some((feerate, _)) = self.pending_update_fee {
+ feerate_per_kw = cmp::max(feerate_per_kw, feerate);
}
- if holder_selected_channel_reserve_satoshis < msg.dust_limit_satoshis {
- return Err(ChannelError::Close(format!("Dust limit ({}) too high for the channel reserve we require the remote to keep ({})", msg.dust_limit_satoshis, holder_selected_channel_reserve_satoshis)));
+ if let Some(feerate) = outbound_feerate_update {
+ feerate_per_kw = cmp::max(feerate_per_kw, feerate);
}
+ cmp::max(2530, feerate_per_kw * 1250 / 1000)
+ }
- // check if the funder's amount for the initial commitment tx is sufficient
- // for full fee payment plus a few HTLCs to ensure the channel will be useful.
- let funders_amount_msat = msg.funding_satoshis * 1000 - msg.push_msat;
- let commitment_tx_fee = Self::commit_tx_fee_msat(msg.feerate_per_kw, MIN_AFFORDABLE_HTLC_COUNT, opt_anchors) / 1000;
- if funders_amount_msat / 1000 < commitment_tx_fee {
- return Err(ChannelError::Close(format!("Funding amount ({} sats) can't even pay fee for initial commitment transaction fee of {} sats.", funders_amount_msat / 1000, commitment_tx_fee)));
+ /// Get forwarding information for the counterparty.
+ pub fn counterparty_forwarding_info(&self) -> Option<CounterpartyForwardingInfo> {
+ self.counterparty_forwarding_info.clone()
+ }
+
+ /// Returns a HTLCStats about inbound pending htlcs
+ fn get_inbound_pending_htlc_stats(&self, outbound_feerate_update: Option<u32>) -> HTLCStats {
+ let context = self;
+ let mut stats = HTLCStats {
+ pending_htlcs: context.pending_inbound_htlcs.len() as u32,
+ pending_htlcs_value_msat: 0,
+ on_counterparty_tx_dust_exposure_msat: 0,
+ on_holder_tx_dust_exposure_msat: 0,
+ holding_cell_msat: 0,
+ on_holder_tx_holding_cell_htlcs_count: 0,
+ };
+
+ let (htlc_timeout_dust_limit, htlc_success_dust_limit) = if context.opt_anchors() {
+ (0, 0)
+ } else {
+ let dust_buffer_feerate = context.get_dust_buffer_feerate(outbound_feerate_update) as u64;
+ (dust_buffer_feerate * htlc_timeout_tx_weight(false) / 1000,
+ dust_buffer_feerate * htlc_success_tx_weight(false) / 1000)
+ };
+ let counterparty_dust_limit_timeout_sat = htlc_timeout_dust_limit + context.counterparty_dust_limit_satoshis;
+ let holder_dust_limit_success_sat = htlc_success_dust_limit + context.holder_dust_limit_satoshis;
+ for ref htlc in context.pending_inbound_htlcs.iter() {
+ stats.pending_htlcs_value_msat += htlc.amount_msat;
+ if htlc.amount_msat / 1000 < counterparty_dust_limit_timeout_sat {
+ stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
+ }
+ if htlc.amount_msat / 1000 < holder_dust_limit_success_sat {
+ stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
+ }
}
+ stats
+ }
- let to_remote_satoshis = funders_amount_msat / 1000 - commitment_tx_fee;
- // While it's reasonable for us to not meet the channel reserve initially (if they don't
- // want to push much to us), our counterparty should always have more than our reserve.
- if to_remote_satoshis < holder_selected_channel_reserve_satoshis {
- return Err(ChannelError::Close("Insufficient funding amount for initial reserve".to_owned()));
+ /// Returns a HTLCStats about pending outbound htlcs, *including* pending adds in our holding cell.
+ fn get_outbound_pending_htlc_stats(&self, outbound_feerate_update: Option<u32>) -> HTLCStats {
+ let context = self;
+ let mut stats = HTLCStats {
+ pending_htlcs: context.pending_outbound_htlcs.len() as u32,
+ pending_htlcs_value_msat: 0,
+ on_counterparty_tx_dust_exposure_msat: 0,
+ on_holder_tx_dust_exposure_msat: 0,
+ holding_cell_msat: 0,
+ on_holder_tx_holding_cell_htlcs_count: 0,
+ };
+
+ let (htlc_timeout_dust_limit, htlc_success_dust_limit) = if context.opt_anchors() {
+ (0, 0)
+ } else {
+ let dust_buffer_feerate = context.get_dust_buffer_feerate(outbound_feerate_update) as u64;
+ (dust_buffer_feerate * htlc_timeout_tx_weight(false) / 1000,
+ dust_buffer_feerate * htlc_success_tx_weight(false) / 1000)
+ };
+ let counterparty_dust_limit_success_sat = htlc_success_dust_limit + context.counterparty_dust_limit_satoshis;
+ let holder_dust_limit_timeout_sat = htlc_timeout_dust_limit + context.holder_dust_limit_satoshis;
+ for ref htlc in context.pending_outbound_htlcs.iter() {
+ stats.pending_htlcs_value_msat += htlc.amount_msat;
+ if htlc.amount_msat / 1000 < counterparty_dust_limit_success_sat {
+ stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
+ }
+ if htlc.amount_msat / 1000 < holder_dust_limit_timeout_sat {
+ stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
+ }
}
- let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
- match &msg.shutdown_scriptpubkey {
- &Some(ref script) => {
- // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
- if script.len() == 0 {
- None
- } else {
- if !script::is_bolt2_compliant(&script, their_features) {
- return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)))
- }
- Some(script.clone())
- }
- },
- // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel
- &None => {
- return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out".to_owned()));
+ for update in context.holding_cell_htlc_updates.iter() {
+ if let &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, .. } = update {
+ stats.pending_htlcs += 1;
+ stats.pending_htlcs_value_msat += amount_msat;
+ stats.holding_cell_msat += amount_msat;
+ if *amount_msat / 1000 < counterparty_dust_limit_success_sat {
+ stats.on_counterparty_tx_dust_exposure_msat += amount_msat;
+ }
+ if *amount_msat / 1000 < holder_dust_limit_timeout_sat {
+ stats.on_holder_tx_dust_exposure_msat += amount_msat;
+ } else {
+ stats.on_holder_tx_holding_cell_htlcs_count += 1;
}
}
- } else { None };
+ }
+ stats
+ }
- let shutdown_scriptpubkey = if config.channel_handshake_config.commit_upfront_shutdown_pubkey {
- match signer_provider.get_shutdown_scriptpubkey() {
- Ok(scriptpubkey) => Some(scriptpubkey),
- Err(_) => return Err(ChannelError::Close("Failed to get upfront shutdown scriptpubkey".to_owned())),
- }
- } else { None };
+ /// Get the available balances, see [`AvailableBalances`]'s fields for more info.
+ /// Doesn't bother handling the
+ /// if-we-removed-it-already-but-haven't-fully-resolved-they-can-still-send-an-inbound-HTLC
+ /// corner case properly.
+ pub fn get_available_balances(&self) -> AvailableBalances {
+ let context = &self;
+ // Note that we have to handle overflow due to the above case.
+ let inbound_stats = context.get_inbound_pending_htlc_stats(None);
+ let outbound_stats = context.get_outbound_pending_htlc_stats(None);
- if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey {
- if !shutdown_scriptpubkey.is_compatible(&their_features) {
- return Err(ChannelError::Close(format!("Provided a scriptpubkey format not accepted by peer: {}", shutdown_scriptpubkey)));
+ let mut balance_msat = context.value_to_self_msat;
+ for ref htlc in context.pending_inbound_htlcs.iter() {
+ if let InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(_)) = htlc.state {
+ balance_msat += htlc.amount_msat;
}
}
+ balance_msat -= outbound_stats.pending_htlcs_value_msat;
- let destination_script = match signer_provider.get_destination_script() {
- Ok(script) => script,
- Err(_) => return Err(ChannelError::Close("Failed to get destination script".to_owned())),
- };
-
- let mut secp_ctx = Secp256k1::new();
- secp_ctx.seeded_randomize(&entropy_source.get_secure_random_bytes());
+ let outbound_capacity_msat = context.value_to_self_msat
+ .saturating_sub(outbound_stats.pending_htlcs_value_msat)
+ .saturating_sub(
+ context.counterparty_selected_channel_reserve_satoshis.unwrap_or(0) * 1000);
- let chan = Channel {
- context: ChannelContext {
- user_id,
+ let mut available_capacity_msat = outbound_capacity_msat;
- config: LegacyChannelConfig {
- options: config.channel_config.clone(),
- announced_channel,
- commit_upfront_shutdown_pubkey: config.channel_handshake_config.commit_upfront_shutdown_pubkey,
- },
+ if context.is_outbound() {
+ // We should mind channel commit tx fee when computing how much of the available capacity
+ // can be used in the next htlc. Mirrors the logic in send_htlc.
+ //
+ // The fee depends on whether the amount we will be sending is above dust or not,
+ // and the answer will in turn change the amount itself — making it a circular
+ // dependency.
+ // This complicates the computation around dust-values, up to the one-htlc-value.
+ let mut real_dust_limit_timeout_sat = context.holder_dust_limit_satoshis;
+ if !context.opt_anchors() {
+ real_dust_limit_timeout_sat += context.feerate_per_kw as u64 * htlc_timeout_tx_weight(false) / 1000;
+ }
- prev_config: None,
+ let htlc_above_dust = HTLCCandidate::new(real_dust_limit_timeout_sat * 1000, HTLCInitiator::LocalOffered);
+ let max_reserved_commit_tx_fee_msat = FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * context.next_local_commit_tx_fee_msat(htlc_above_dust, Some(()));
+ let htlc_dust = HTLCCandidate::new(real_dust_limit_timeout_sat * 1000 - 1, HTLCInitiator::LocalOffered);
+ let min_reserved_commit_tx_fee_msat = FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * context.next_local_commit_tx_fee_msat(htlc_dust, Some(()));
- inbound_handshake_limits_override: None,
-
- temporary_channel_id: Some(msg.temporary_channel_id),
- channel_id: msg.temporary_channel_id,
- channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
- announcement_sigs_state: AnnouncementSigsState::NotSent,
- secp_ctx,
-
- latest_monitor_update_id: 0,
-
- holder_signer,
- shutdown_scriptpubkey,
- destination_script,
-
- cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
- cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
- value_to_self_msat: msg.push_msat,
-
- pending_inbound_htlcs: Vec::new(),
- pending_outbound_htlcs: Vec::new(),
- holding_cell_htlc_updates: Vec::new(),
- pending_update_fee: None,
- holding_cell_update_fee: None,
- next_holder_htlc_id: 0,
- next_counterparty_htlc_id: 0,
- update_time_counter: 1,
+ // We will first subtract the fee as if we were above-dust. Then, if the resulting
+ // value ends up being below dust, we have this fee available again. In that case,
+ // match the value to right-below-dust.
+ let mut capacity_minus_commitment_fee_msat: i64 = (available_capacity_msat as i64) - (max_reserved_commit_tx_fee_msat as i64);
+ if capacity_minus_commitment_fee_msat < (real_dust_limit_timeout_sat as i64) * 1000 {
+ let one_htlc_difference_msat = max_reserved_commit_tx_fee_msat - min_reserved_commit_tx_fee_msat;
+ debug_assert!(one_htlc_difference_msat != 0);
+ capacity_minus_commitment_fee_msat += one_htlc_difference_msat as i64;
+ capacity_minus_commitment_fee_msat = cmp::min(real_dust_limit_timeout_sat as i64 * 1000 - 1, capacity_minus_commitment_fee_msat);
+ available_capacity_msat = cmp::max(0, cmp::min(capacity_minus_commitment_fee_msat, available_capacity_msat as i64)) as u64;
+ } else {
+ available_capacity_msat = capacity_minus_commitment_fee_msat as u64;
+ }
+ } else {
+ // If the channel is inbound (i.e. counterparty pays the fee), we need to make sure
+ // sending a new HTLC won't reduce their balance below our reserve threshold.
+ let mut real_dust_limit_success_sat = context.counterparty_dust_limit_satoshis;
+ if !context.opt_anchors() {
+ real_dust_limit_success_sat += context.feerate_per_kw as u64 * htlc_success_tx_weight(false) / 1000;
+ }
- resend_order: RAACommitmentOrder::CommitmentFirst,
+ let htlc_above_dust = HTLCCandidate::new(real_dust_limit_success_sat * 1000, HTLCInitiator::LocalOffered);
+ let max_reserved_commit_tx_fee_msat = context.next_remote_commit_tx_fee_msat(htlc_above_dust, None);
- monitor_pending_channel_ready: false,
- monitor_pending_revoke_and_ack: false,
- monitor_pending_commitment_signed: false,
- monitor_pending_forwards: Vec::new(),
- monitor_pending_failures: Vec::new(),
- monitor_pending_finalized_fulfills: Vec::new(),
+ let holder_selected_chan_reserve_msat = context.holder_selected_channel_reserve_satoshis * 1000;
+ let remote_balance_msat = (context.channel_value_satoshis * 1000 - context.value_to_self_msat)
+ .saturating_sub(inbound_stats.pending_htlcs_value_msat);
- #[cfg(debug_assertions)]
- holder_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
- #[cfg(debug_assertions)]
- counterparty_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
+ if remote_balance_msat < max_reserved_commit_tx_fee_msat + holder_selected_chan_reserve_msat {
+ // If another HTLC's fee would reduce the remote's balance below the reserve limit
+ // we've selected for them, we can only send dust HTLCs.
+ available_capacity_msat = cmp::min(available_capacity_msat, real_dust_limit_success_sat * 1000 - 1);
+ }
+ }
- last_sent_closing_fee: None,
- pending_counterparty_closing_signed: None,
- closing_fee_limits: None,
- target_closing_feerate_sats_per_kw: None,
+ let mut next_outbound_htlc_minimum_msat = context.counterparty_htlc_minimum_msat;
- inbound_awaiting_accept: true,
+ // If we get close to our maximum dust exposure, we end up in a situation where we can send
+ // between zero and the remaining dust exposure limit remaining OR above the dust limit.
+ // Because we cannot express this as a simple min/max, we prefer to tell the user they can
+ // send above the dust limit (as the router can always overpay to meet the dust limit).
+ let mut remaining_msat_below_dust_exposure_limit = None;
+ let mut dust_exposure_dust_limit_msat = 0;
- funding_tx_confirmed_in: None,
- funding_tx_confirmation_height: 0,
- short_channel_id: None,
- channel_creation_height: current_chain_height,
+ let (htlc_success_dust_limit, htlc_timeout_dust_limit) = if context.opt_anchors() {
+ (context.counterparty_dust_limit_satoshis, context.holder_dust_limit_satoshis)
+ } else {
+ let dust_buffer_feerate = context.get_dust_buffer_feerate(None) as u64;
+ (context.counterparty_dust_limit_satoshis + dust_buffer_feerate * htlc_success_tx_weight(false) / 1000,
+ context.holder_dust_limit_satoshis + dust_buffer_feerate * htlc_timeout_tx_weight(false) / 1000)
+ };
+ let on_counterparty_dust_htlc_exposure_msat = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat;
+ if on_counterparty_dust_htlc_exposure_msat as i64 + htlc_success_dust_limit as i64 * 1000 - 1 > context.get_max_dust_htlc_exposure_msat() as i64 {
+ remaining_msat_below_dust_exposure_limit =
+ Some(context.get_max_dust_htlc_exposure_msat().saturating_sub(on_counterparty_dust_htlc_exposure_msat));
+ dust_exposure_dust_limit_msat = cmp::max(dust_exposure_dust_limit_msat, htlc_success_dust_limit * 1000);
+ }
- feerate_per_kw: msg.feerate_per_kw,
- channel_value_satoshis: msg.funding_satoshis,
- counterparty_dust_limit_satoshis: msg.dust_limit_satoshis,
- holder_dust_limit_satoshis: MIN_CHAN_DUST_LIMIT_SATOSHIS,
- counterparty_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
- holder_max_htlc_value_in_flight_msat: get_holder_max_htlc_value_in_flight_msat(msg.funding_satoshis, &config.channel_handshake_config),
- counterparty_selected_channel_reserve_satoshis: Some(msg.channel_reserve_satoshis),
- holder_selected_channel_reserve_satoshis,
- counterparty_htlc_minimum_msat: msg.htlc_minimum_msat,
- holder_htlc_minimum_msat: if config.channel_handshake_config.our_htlc_minimum_msat == 0 { 1 } else { config.channel_handshake_config.our_htlc_minimum_msat },
- counterparty_max_accepted_htlcs: msg.max_accepted_htlcs,
- holder_max_accepted_htlcs: cmp::min(config.channel_handshake_config.our_max_accepted_htlcs, MAX_HTLCS),
- minimum_depth: Some(cmp::max(config.channel_handshake_config.minimum_depth, 1)),
+ let on_holder_dust_htlc_exposure_msat = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
+ if on_holder_dust_htlc_exposure_msat as i64 + htlc_timeout_dust_limit as i64 * 1000 - 1 > context.get_max_dust_htlc_exposure_msat() as i64 {
+ remaining_msat_below_dust_exposure_limit = Some(cmp::min(
+ remaining_msat_below_dust_exposure_limit.unwrap_or(u64::max_value()),
+ context.get_max_dust_htlc_exposure_msat().saturating_sub(on_holder_dust_htlc_exposure_msat)));
+ dust_exposure_dust_limit_msat = cmp::max(dust_exposure_dust_limit_msat, htlc_timeout_dust_limit * 1000);
+ }
- counterparty_forwarding_info: None,
+ if let Some(remaining_limit_msat) = remaining_msat_below_dust_exposure_limit {
+ if available_capacity_msat < dust_exposure_dust_limit_msat {
+ available_capacity_msat = cmp::min(available_capacity_msat, remaining_limit_msat);
+ } else {
+ next_outbound_htlc_minimum_msat = cmp::max(next_outbound_htlc_minimum_msat, dust_exposure_dust_limit_msat);
+ }
+ }
- channel_transaction_parameters: ChannelTransactionParameters {
- holder_pubkeys: pubkeys,
- holder_selected_contest_delay: config.channel_handshake_config.our_to_self_delay,
- is_outbound_from_holder: false,
- counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
- selected_contest_delay: msg.to_self_delay,
- pubkeys: counterparty_pubkeys,
- }),
- funding_outpoint: None,
- opt_anchors: if opt_anchors { Some(()) } else { None },
- opt_non_zero_fee_anchors: None
- },
- funding_transaction: None,
+ available_capacity_msat = cmp::min(available_capacity_msat,
+ context.counterparty_max_htlc_value_in_flight_msat - outbound_stats.pending_htlcs_value_msat);
- counterparty_cur_commitment_point: Some(msg.first_per_commitment_point),
- counterparty_prev_commitment_point: None,
- counterparty_node_id,
+ if outbound_stats.pending_htlcs + 1 > context.counterparty_max_accepted_htlcs as u32 {
+ available_capacity_msat = 0;
+ }
- counterparty_shutdown_scriptpubkey,
+ AvailableBalances {
+ inbound_capacity_msat: cmp::max(context.channel_value_satoshis as i64 * 1000
+ - context.value_to_self_msat as i64
+ - context.get_inbound_pending_htlc_stats(None).pending_htlcs_value_msat as i64
+ - context.holder_selected_channel_reserve_satoshis as i64 * 1000,
+ 0) as u64,
+ outbound_capacity_msat,
+ next_outbound_htlc_limit_msat: available_capacity_msat,
+ next_outbound_htlc_minimum_msat,
+ balance_msat,
+ }
+ }
- commitment_secrets: CounterpartyCommitmentSecrets::new(),
+ pub fn get_holder_counterparty_selected_channel_reserve_satoshis(&self) -> (u64, Option<u64>) {
+ let context = &self;
+ (context.holder_selected_channel_reserve_satoshis, context.counterparty_selected_channel_reserve_satoshis)
+ }
- channel_update_status: ChannelUpdateStatus::Enabled,
- closing_signed_in_flight: false,
+ /// Get the commitment tx fee for the local's (i.e. our) next commitment transaction based on the
+ /// number of pending HTLCs that are on track to be in our next commitment tx.
+ ///
+ /// Optionally includes the `HTLCCandidate` given by `htlc` and an additional non-dust HTLC if
+ /// `fee_spike_buffer_htlc` is `Some`.
+ ///
+ /// The first extra HTLC is useful for determining whether we can accept a further HTLC, the
+ /// second allows for creating a buffer to ensure a further HTLC can always be accepted/added.
+ ///
+ /// Dust HTLCs are excluded.
+ fn next_local_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
+ let context = &self;
+ assert!(context.is_outbound());
- announcement_sigs: None,
+ let (htlc_success_dust_limit, htlc_timeout_dust_limit) = if context.opt_anchors() {
+ (0, 0)
+ } else {
+ (context.feerate_per_kw as u64 * htlc_success_tx_weight(false) / 1000,
+ context.feerate_per_kw as u64 * htlc_timeout_tx_weight(false) / 1000)
+ };
+ let real_dust_limit_success_sat = htlc_success_dust_limit + context.holder_dust_limit_satoshis;
+ let real_dust_limit_timeout_sat = htlc_timeout_dust_limit + context.holder_dust_limit_satoshis;
- #[cfg(any(test, fuzzing))]
- next_local_commitment_tx_fee_info_cached: Mutex::new(None),
- #[cfg(any(test, fuzzing))]
- next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
+ let mut addl_htlcs = 0;
+ if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
+ match htlc.origin {
+ HTLCInitiator::LocalOffered => {
+ if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
+ addl_htlcs += 1;
+ }
+ },
+ HTLCInitiator::RemoteOffered => {
+ if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
+ addl_htlcs += 1;
+ }
+ }
+ }
- workaround_lnd_bug_4006: None,
- sent_message_awaiting_response: None,
+ let mut included_htlcs = 0;
+ for ref htlc in context.pending_inbound_htlcs.iter() {
+ if htlc.amount_msat / 1000 < real_dust_limit_success_sat {
+ continue
+ }
+ // We include LocalRemoved HTLCs here because we may still need to broadcast a commitment
+ // transaction including this HTLC if it times out before they RAA.
+ included_htlcs += 1;
+ }
- latest_inbound_scid_alias: None,
- outbound_scid_alias,
+ for ref htlc in context.pending_outbound_htlcs.iter() {
+ if htlc.amount_msat / 1000 < real_dust_limit_timeout_sat {
+ continue
+ }
+ match htlc.state {
+ OutboundHTLCState::LocalAnnounced {..} => included_htlcs += 1,
+ OutboundHTLCState::Committed => included_htlcs += 1,
+ OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
+ // We don't include AwaitingRemoteRevokeToRemove HTLCs because our next commitment
+ // transaction won't be generated until they send us their next RAA, which will mean
+ // dropping any HTLCs in this state.
+ _ => {},
+ }
+ }
- channel_pending_event_emitted: false,
- channel_ready_event_emitted: false,
+ for htlc in context.holding_cell_htlc_updates.iter() {
+ match htlc {
+ &HTLCUpdateAwaitingACK::AddHTLC { amount_msat, .. } => {
+ if amount_msat / 1000 < real_dust_limit_timeout_sat {
+ continue
+ }
+ included_htlcs += 1
+ },
+ _ => {}, // Don't include claims/fails that are awaiting ack, because once we get the
+ // ack we're guaranteed to never include them in commitment txs anymore.
+ }
+ }
- #[cfg(any(test, fuzzing))]
- historical_inbound_htlc_fulfills: HashSet::new(),
+ let num_htlcs = included_htlcs + addl_htlcs;
+ let res = commit_tx_fee_msat(context.feerate_per_kw, num_htlcs, context.opt_anchors());
+ #[cfg(any(test, fuzzing))]
+ {
+ let mut fee = res;
+ if fee_spike_buffer_htlc.is_some() {
+ fee = commit_tx_fee_msat(context.feerate_per_kw, num_htlcs - 1, context.opt_anchors());
+ }
+ let total_pending_htlcs = context.pending_inbound_htlcs.len() + context.pending_outbound_htlcs.len()
+ + context.holding_cell_htlc_updates.len();
+ let commitment_tx_info = CommitmentTxInfoCached {
+ fee,
+ total_pending_htlcs,
+ next_holder_htlc_id: match htlc.origin {
+ HTLCInitiator::LocalOffered => context.next_holder_htlc_id + 1,
+ HTLCInitiator::RemoteOffered => context.next_holder_htlc_id,
+ },
+ next_counterparty_htlc_id: match htlc.origin {
+ HTLCInitiator::LocalOffered => context.next_counterparty_htlc_id,
+ HTLCInitiator::RemoteOffered => context.next_counterparty_htlc_id + 1,
+ },
+ feerate: context.feerate_per_kw,
+ };
+ *context.next_local_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
+ }
+ res
+ }
- channel_type,
- channel_keys_id,
+ /// Get the commitment tx fee for the remote's next commitment transaction based on the number of
+ /// pending HTLCs that are on track to be in their next commitment tx
+ ///
+ /// Optionally includes the `HTLCCandidate` given by `htlc` and an additional non-dust HTLC if
+ /// `fee_spike_buffer_htlc` is `Some`.
+ ///
+ /// The first extra HTLC is useful for determining whether we can accept a further HTLC, the
+ /// second allows for creating a buffer to ensure a further HTLC can always be accepted/added.
+ ///
+ /// Dust HTLCs are excluded.
+ fn next_remote_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
+ let context = &self;
+ assert!(!context.is_outbound());
- pending_monitor_updates: Vec::new(),
- }
+ let (htlc_success_dust_limit, htlc_timeout_dust_limit) = if context.opt_anchors() {
+ (0, 0)
+ } else {
+ (context.feerate_per_kw as u64 * htlc_success_tx_weight(false) / 1000,
+ context.feerate_per_kw as u64 * htlc_timeout_tx_weight(false) / 1000)
};
+ let real_dust_limit_success_sat = htlc_success_dust_limit + context.counterparty_dust_limit_satoshis;
+ let real_dust_limit_timeout_sat = htlc_timeout_dust_limit + context.counterparty_dust_limit_satoshis;
- Ok(chan)
- }
-
- /// Transaction nomenclature is somewhat confusing here as there are many different cases - a
- /// transaction is referred to as "a's transaction" implying that a will be able to broadcast
- /// the transaction. Thus, b will generally be sending a signature over such a transaction to
- /// a, and a can revoke the transaction by providing b the relevant per_commitment_secret. As
- /// such, a transaction is generally the result of b increasing the amount paid to a (or adding
- /// an HTLC to a).
- /// @local is used only to convert relevant internal structures which refer to remote vs local
- /// to decide value of outputs and direction of HTLCs.
- /// @generated_by_local is used to determine *which* HTLCs to include - noting that the HTLC
- /// state may indicate that one peer has informed the other that they'd like to add an HTLC but
- /// have not yet committed it. Such HTLCs will only be included in transactions which are being
- /// generated by the peer which proposed adding the HTLCs, and thus we need to understand both
- /// which peer generated this transaction and "to whom" this transaction flows.
- #[inline]
- fn build_commitment_transaction<L: Deref>(&self, commitment_number: u64, keys: &TxCreationKeys, local: bool, generated_by_local: bool, logger: &L) -> CommitmentStats
- where L::Target: Logger
- {
- let mut included_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::new();
- let num_htlcs = self.context.pending_inbound_htlcs.len() + self.context.pending_outbound_htlcs.len();
- let mut included_non_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(num_htlcs);
-
- let broadcaster_dust_limit_satoshis = if local { self.context.holder_dust_limit_satoshis } else { self.context.counterparty_dust_limit_satoshis };
- let mut remote_htlc_total_msat = 0;
- let mut local_htlc_total_msat = 0;
- let mut value_to_self_msat_offset = 0;
-
- let mut feerate_per_kw = self.context.feerate_per_kw;
- if let Some((feerate, update_state)) = self.context.pending_update_fee {
- if match update_state {
- // Note that these match the inclusion criteria when scanning
- // pending_inbound_htlcs below.
- FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); !generated_by_local },
- FeeUpdateState::AwaitingRemoteRevokeToAnnounce => { debug_assert!(!self.is_outbound()); !generated_by_local },
- FeeUpdateState::Outbound => { assert!(self.is_outbound()); generated_by_local },
- } {
- feerate_per_kw = feerate;
- }
- }
-
- log_trace!(logger, "Building commitment transaction number {} (really {} xor {}) for channel {} for {}, generated by {} with fee {}...",
- commitment_number, (INITIAL_COMMITMENT_NUMBER - commitment_number),
- get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound()),
- log_bytes!(self.context.channel_id), if local { "us" } else { "remote" }, if generated_by_local { "us" } else { "remote" }, feerate_per_kw);
-
- macro_rules! get_htlc_in_commitment {
- ($htlc: expr, $offered: expr) => {
- HTLCOutputInCommitment {
- offered: $offered,
- amount_msat: $htlc.amount_msat,
- cltv_expiry: $htlc.cltv_expiry,
- payment_hash: $htlc.payment_hash,
- transaction_output_index: None
+ let mut addl_htlcs = 0;
+ if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
+ match htlc.origin {
+ HTLCInitiator::LocalOffered => {
+ if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
+ addl_htlcs += 1;
}
- }
- }
-
- macro_rules! add_htlc_output {
- ($htlc: expr, $outbound: expr, $source: expr, $state_name: expr) => {
- if $outbound == local { // "offered HTLC output"
- let htlc_in_tx = get_htlc_in_commitment!($htlc, true);
- let htlc_tx_fee = if self.context.opt_anchors() {
- 0
- } else {
- feerate_per_kw as u64 * htlc_timeout_tx_weight(false) / 1000
- };
- if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + htlc_tx_fee {
- log_trace!(logger, " ...including {} {} HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
- included_non_dust_htlcs.push((htlc_in_tx, $source));
- } else {
- log_trace!(logger, " ...including {} {} dust HTLC {} (hash {}) with value {} due to dust limit", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
- included_dust_htlcs.push((htlc_in_tx, $source));
- }
- } else {
- let htlc_in_tx = get_htlc_in_commitment!($htlc, false);
- let htlc_tx_fee = if self.context.opt_anchors() {
- 0
- } else {
- feerate_per_kw as u64 * htlc_success_tx_weight(false) / 1000
- };
- if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + htlc_tx_fee {
- log_trace!(logger, " ...including {} {} HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
- included_non_dust_htlcs.push((htlc_in_tx, $source));
- } else {
- log_trace!(logger, " ...including {} {} dust HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
- included_dust_htlcs.push((htlc_in_tx, $source));
- }
+ },
+ HTLCInitiator::RemoteOffered => {
+ if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
+ addl_htlcs += 1;
}
}
}
- for ref htlc in self.context.pending_inbound_htlcs.iter() {
- let (include, state_name) = match htlc.state {
- InboundHTLCState::RemoteAnnounced(_) => (!generated_by_local, "RemoteAnnounced"),
- InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) => (!generated_by_local, "AwaitingRemoteRevokeToAnnounce"),
- InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => (true, "AwaitingAnnouncedRemoteRevoke"),
- InboundHTLCState::Committed => (true, "Committed"),
- InboundHTLCState::LocalRemoved(_) => (!generated_by_local, "LocalRemoved"),
- };
-
- if include {
- add_htlc_output!(htlc, false, None, state_name);
- remote_htlc_total_msat += htlc.amount_msat;
- } else {
- log_trace!(logger, " ...not including inbound HTLC {} (hash {}) with value {} due to state ({})", htlc.htlc_id, log_bytes!(htlc.payment_hash.0), htlc.amount_msat, state_name);
- match &htlc.state {
- &InboundHTLCState::LocalRemoved(ref reason) => {
- if generated_by_local {
- if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
- value_to_self_msat_offset += htlc.amount_msat as i64;
- }
- }
- },
- _ => {},
- }
+ // When calculating the set of HTLCs which will be included in their next commitment_signed, all
+ // non-dust inbound HTLCs are included (as all states imply it will be included) and only
+ // committed outbound HTLCs, see below.
+ let mut included_htlcs = 0;
+ for ref htlc in context.pending_inbound_htlcs.iter() {
+ if htlc.amount_msat / 1000 <= real_dust_limit_timeout_sat {
+ continue
}
+ included_htlcs += 1;
}
- let mut preimages: Vec<PaymentPreimage> = Vec::new();
-
- for ref htlc in self.context.pending_outbound_htlcs.iter() {
- let (include, state_name) = match htlc.state {
- OutboundHTLCState::LocalAnnounced(_) => (generated_by_local, "LocalAnnounced"),
- OutboundHTLCState::Committed => (true, "Committed"),
- OutboundHTLCState::RemoteRemoved(_) => (generated_by_local, "RemoteRemoved"),
- OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) => (generated_by_local, "AwaitingRemoteRevokeToRemove"),
- OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) => (false, "AwaitingRemovedRemoteRevoke"),
- };
-
- let preimage_opt = match htlc.state {
- OutboundHTLCState::RemoteRemoved(OutboundHTLCOutcome::Success(p)) => p,
- OutboundHTLCState::AwaitingRemoteRevokeToRemove(OutboundHTLCOutcome::Success(p)) => p,
- OutboundHTLCState::AwaitingRemovedRemoteRevoke(OutboundHTLCOutcome::Success(p)) => p,
- _ => None,
- };
-
- if let Some(preimage) = preimage_opt {
- preimages.push(preimage);
+ for ref htlc in context.pending_outbound_htlcs.iter() {
+ if htlc.amount_msat / 1000 <= real_dust_limit_success_sat {
+ continue
}
-
- if include {
- add_htlc_output!(htlc, true, Some(&htlc.source), state_name);
- local_htlc_total_msat += htlc.amount_msat;
- } else {
- log_trace!(logger, " ...not including outbound HTLC {} (hash {}) with value {} due to state ({})", htlc.htlc_id, log_bytes!(htlc.payment_hash.0), htlc.amount_msat, state_name);
- match htlc.state {
- OutboundHTLCState::AwaitingRemoteRevokeToRemove(OutboundHTLCOutcome::Success(_))|OutboundHTLCState::AwaitingRemovedRemoteRevoke(OutboundHTLCOutcome::Success(_)) => {
- value_to_self_msat_offset -= htlc.amount_msat as i64;
- },
- OutboundHTLCState::RemoteRemoved(OutboundHTLCOutcome::Success(_)) => {
- if !generated_by_local {
- value_to_self_msat_offset -= htlc.amount_msat as i64;
- }
- },
- _ => {},
- }
+ // We only include outbound HTLCs if it will not be included in their next commitment_signed,
+ // i.e. if they've responded to us with an RAA after announcement.
+ match htlc.state {
+ OutboundHTLCState::Committed => included_htlcs += 1,
+ OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
+ OutboundHTLCState::LocalAnnounced { .. } => included_htlcs += 1,
+ _ => {},
}
}
- let mut value_to_self_msat: i64 = (self.context.value_to_self_msat - local_htlc_total_msat) as i64 + value_to_self_msat_offset;
- assert!(value_to_self_msat >= 0);
- // Note that in case they have several just-awaiting-last-RAA fulfills in-progress (ie
- // AwaitingRemoteRevokeToRemove or AwaitingRemovedRemoteRevoke) we may have allowed them to
- // "violate" their reserve value by couting those against it. Thus, we have to convert
- // everything to i64 before subtracting as otherwise we can overflow.
- let mut value_to_remote_msat: i64 = (self.context.channel_value_satoshis * 1000) as i64 - (self.context.value_to_self_msat as i64) - (remote_htlc_total_msat as i64) - value_to_self_msat_offset;
- assert!(value_to_remote_msat >= 0);
-
- #[cfg(debug_assertions)]
+ let num_htlcs = included_htlcs + addl_htlcs;
+ let res = commit_tx_fee_msat(context.feerate_per_kw, num_htlcs, context.opt_anchors());
+ #[cfg(any(test, fuzzing))]
{
- // Make sure that the to_self/to_remote is always either past the appropriate
- // channel_reserve *or* it is making progress towards it.
- let mut broadcaster_max_commitment_tx_output = if generated_by_local {
- self.context.holder_max_commitment_tx_output.lock().unwrap()
- } else {
- self.context.counterparty_max_commitment_tx_output.lock().unwrap()
+ let mut fee = res;
+ if fee_spike_buffer_htlc.is_some() {
+ fee = commit_tx_fee_msat(context.feerate_per_kw, num_htlcs - 1, context.opt_anchors());
+ }
+ let total_pending_htlcs = context.pending_inbound_htlcs.len() + context.pending_outbound_htlcs.len();
+ let commitment_tx_info = CommitmentTxInfoCached {
+ fee,
+ total_pending_htlcs,
+ next_holder_htlc_id: match htlc.origin {
+ HTLCInitiator::LocalOffered => context.next_holder_htlc_id + 1,
+ HTLCInitiator::RemoteOffered => context.next_holder_htlc_id,
+ },
+ next_counterparty_htlc_id: match htlc.origin {
+ HTLCInitiator::LocalOffered => context.next_counterparty_htlc_id,
+ HTLCInitiator::RemoteOffered => context.next_counterparty_htlc_id + 1,
+ },
+ feerate: context.feerate_per_kw,
};
- debug_assert!(broadcaster_max_commitment_tx_output.0 <= value_to_self_msat as u64 || value_to_self_msat / 1000 >= self.context.counterparty_selected_channel_reserve_satoshis.unwrap() as i64);
- broadcaster_max_commitment_tx_output.0 = cmp::max(broadcaster_max_commitment_tx_output.0, value_to_self_msat as u64);
- debug_assert!(broadcaster_max_commitment_tx_output.1 <= value_to_remote_msat as u64 || value_to_remote_msat / 1000 >= self.context.holder_selected_channel_reserve_satoshis as i64);
- broadcaster_max_commitment_tx_output.1 = cmp::max(broadcaster_max_commitment_tx_output.1, value_to_remote_msat as u64);
+ *context.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
}
+ res
+ }
- let total_fee_sat = Channel::<Signer>::commit_tx_fee_sat(feerate_per_kw, included_non_dust_htlcs.len(), self.context.channel_transaction_parameters.opt_anchors.is_some());
- let anchors_val = if self.context.channel_transaction_parameters.opt_anchors.is_some() { ANCHOR_OUTPUT_VALUE_SATOSHI * 2 } else { 0 } as i64;
- let (value_to_self, value_to_remote) = if self.is_outbound() {
- (value_to_self_msat / 1000 - anchors_val - total_fee_sat as i64, value_to_remote_msat / 1000)
+ /// Returns transaction if there is pending funding transaction that is yet to broadcast
+ pub fn unbroadcasted_funding(&self) -> Option<Transaction> {
+ if self.channel_state & (ChannelState::FundingCreated as u32) != 0 {
+ self.funding_transaction.clone()
} else {
- (value_to_self_msat / 1000, value_to_remote_msat / 1000 - anchors_val - total_fee_sat as i64)
- };
+ None
+ }
+ }
+}
- let mut value_to_a = if local { value_to_self } else { value_to_remote };
- let mut value_to_b = if local { value_to_remote } else { value_to_self };
- let (funding_pubkey_a, funding_pubkey_b) = if local {
- (self.get_holder_pubkeys().funding_pubkey, self.get_counterparty_pubkeys().funding_pubkey)
- } else {
- (self.get_counterparty_pubkeys().funding_pubkey, self.get_holder_pubkeys().funding_pubkey)
- };
+// Internal utility functions for channels
- if value_to_a >= (broadcaster_dust_limit_satoshis as i64) {
- log_trace!(logger, " ...including {} output with value {}", if local { "to_local" } else { "to_remote" }, value_to_a);
- } else {
- value_to_a = 0;
- }
+/// Returns the value to use for `holder_max_htlc_value_in_flight_msat` as a percentage of the
+/// `channel_value_satoshis` in msat, set through
+/// [`ChannelHandshakeConfig::max_inbound_htlc_value_in_flight_percent_of_channel`]
+///
+/// The effective percentage is lower bounded by 1% and upper bounded by 100%.
+///
+/// [`ChannelHandshakeConfig::max_inbound_htlc_value_in_flight_percent_of_channel`]: crate::util::config::ChannelHandshakeConfig::max_inbound_htlc_value_in_flight_percent_of_channel
+fn get_holder_max_htlc_value_in_flight_msat(channel_value_satoshis: u64, config: &ChannelHandshakeConfig) -> u64 {
+ let configured_percent = if config.max_inbound_htlc_value_in_flight_percent_of_channel < 1 {
+ 1
+ } else if config.max_inbound_htlc_value_in_flight_percent_of_channel > 100 {
+ 100
+ } else {
+ config.max_inbound_htlc_value_in_flight_percent_of_channel as u64
+ };
+ channel_value_satoshis * 10 * configured_percent
+}
- if value_to_b >= (broadcaster_dust_limit_satoshis as i64) {
- log_trace!(logger, " ...including {} output with value {}", if local { "to_remote" } else { "to_local" }, value_to_b);
- } else {
- value_to_b = 0;
- }
+/// Returns a minimum channel reserve value the remote needs to maintain,
+/// required by us according to the configured or default
+/// [`ChannelHandshakeConfig::their_channel_reserve_proportional_millionths`]
+///
+/// Guaranteed to return a value no larger than channel_value_satoshis
+///
+/// This is used both for outbound and inbound channels and has lower bound
+/// of `MIN_THEIR_CHAN_RESERVE_SATOSHIS`.
+pub(crate) fn get_holder_selected_channel_reserve_satoshis(channel_value_satoshis: u64, config: &UserConfig) -> u64 {
+ let calculated_reserve = channel_value_satoshis.saturating_mul(config.channel_handshake_config.their_channel_reserve_proportional_millionths as u64) / 1_000_000;
+ cmp::min(channel_value_satoshis, cmp::max(calculated_reserve, MIN_THEIR_CHAN_RESERVE_SATOSHIS))
+}
- let num_nondust_htlcs = included_non_dust_htlcs.len();
+/// This is for legacy reasons, present for forward-compatibility.
+/// LDK versions older than 0.0.104 don't know how read/handle values other than default
+/// from storage. Hence, we use this function to not persist default values of
+/// `holder_selected_channel_reserve_satoshis` for channels into storage.
+pub(crate) fn get_legacy_default_holder_selected_channel_reserve_satoshis(channel_value_satoshis: u64) -> u64 {
+ let (q, _) = channel_value_satoshis.overflowing_div(100);
+ cmp::min(channel_value_satoshis, cmp::max(q, 1000))
+}
- let channel_parameters =
- if local { self.context.channel_transaction_parameters.as_holder_broadcastable() }
- else { self.context.channel_transaction_parameters.as_counterparty_broadcastable() };
- let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(commitment_number,
- value_to_a as u64,
- value_to_b as u64,
- self.context.channel_transaction_parameters.opt_anchors.is_some(),
- funding_pubkey_a,
- funding_pubkey_b,
- keys.clone(),
- feerate_per_kw,
- &mut included_non_dust_htlcs,
- &channel_parameters
- );
- let mut htlcs_included = included_non_dust_htlcs;
- // The unwrap is safe, because all non-dust HTLCs have been assigned an output index
- htlcs_included.sort_unstable_by_key(|h| h.0.transaction_output_index.unwrap());
- htlcs_included.append(&mut included_dust_htlcs);
-
- // For the stats, trimmed-to-0 the value in msats accordingly
- value_to_self_msat = if (value_to_self_msat * 1000) < broadcaster_dust_limit_satoshis as i64 { 0 } else { value_to_self_msat };
- value_to_remote_msat = if (value_to_remote_msat * 1000) < broadcaster_dust_limit_satoshis as i64 { 0 } else { value_to_remote_msat };
-
- CommitmentStats {
- tx,
- feerate_per_kw,
- total_fee_sat,
- num_nondust_htlcs,
- htlcs_included,
- local_balance_msat: value_to_self_msat as u64,
- remote_balance_msat: value_to_remote_msat as u64,
- preimages
- }
- }
+// Get the fee cost in SATS of a commitment tx with a given number of HTLC outputs.
+// Note that num_htlcs should not include dust HTLCs.
+#[inline]
+fn commit_tx_fee_sat(feerate_per_kw: u32, num_htlcs: usize, opt_anchors: bool) -> u64 {
+ feerate_per_kw as u64 * (commitment_tx_base_weight(opt_anchors) + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000
+}
- #[inline]
- fn get_closing_scriptpubkey(&self) -> Script {
- // The shutdown scriptpubkey is set on channel opening when option_upfront_shutdown_script
- // is signaled. Otherwise, it is set when sending a shutdown message. Calling this method
- // outside of those situations will fail.
- self.context.shutdown_scriptpubkey.clone().unwrap().into_inner()
- }
+// Get the fee cost in MSATS of a commitment tx with a given number of HTLC outputs.
+// Note that num_htlcs should not include dust HTLCs.
+fn commit_tx_fee_msat(feerate_per_kw: u32, num_htlcs: usize, opt_anchors: bool) -> u64 {
+ // Note that we need to divide before multiplying to round properly,
+ // since the lowest denomination of bitcoin on-chain is the satoshi.
+ (commitment_tx_base_weight(opt_anchors) + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) * feerate_per_kw as u64 / 1000 * 1000
+}
- #[inline]
- fn get_closing_transaction_weight(&self, a_scriptpubkey: Option<&Script>, b_scriptpubkey: Option<&Script>) -> u64 {
- let mut ret =
- (4 + // version
- 1 + // input count
- 36 + // prevout
- 1 + // script length (0)
- 4 + // sequence
- 1 + // output count
- 4 // lock time
- )*4 + // * 4 for non-witness parts
- 2 + // witness marker and flag
- 1 + // witness element count
- 4 + // 4 element lengths (2 sigs, multisig dummy, and witness script)
- self.get_funding_redeemscript().len() as u64 + // funding witness script
- 2*(1 + 71); // two signatures + sighash type flags
- if let Some(spk) = a_scriptpubkey {
- ret += ((8+1) + // output values and script length
- spk.len() as u64) * 4; // scriptpubkey and witness multiplier
- }
- if let Some(spk) = b_scriptpubkey {
- ret += ((8+1) + // output values and script length
- spk.len() as u64) * 4; // scriptpubkey and witness multiplier
- }
- ret
- }
+// TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
+// has been completed, and then turn into a Channel to get compiler-time enforcement of things like
+// calling channel_id() before we're set up or things like get_outbound_funding_signed on an
+// inbound channel.
+//
+// Holder designates channel data owned for the benefit of the user client.
+// Counterparty designates channel data owned by the another channel participant entity.
+pub(super) struct Channel<Signer: ChannelSigner> {
+ pub context: ChannelContext<Signer>,
+}
- #[inline]
- fn build_closing_transaction(&self, proposed_total_fee_satoshis: u64, skip_remote_output: bool) -> (ClosingTransaction, u64) {
- assert!(self.context.pending_inbound_htlcs.is_empty());
- assert!(self.context.pending_outbound_htlcs.is_empty());
- assert!(self.context.pending_update_fee.is_none());
+#[cfg(any(test, fuzzing))]
+struct CommitmentTxInfoCached {
+ fee: u64,
+ total_pending_htlcs: usize,
+ next_holder_htlc_id: u64,
+ next_counterparty_htlc_id: u64,
+ feerate: u32,
+}
- let mut total_fee_satoshis = proposed_total_fee_satoshis;
- let mut value_to_holder: i64 = (self.context.value_to_self_msat as i64) / 1000 - if self.is_outbound() { total_fee_satoshis as i64 } else { 0 };
- let mut value_to_counterparty: i64 = ((self.context.channel_value_satoshis * 1000 - self.context.value_to_self_msat) as i64 / 1000) - if self.is_outbound() { 0 } else { total_fee_satoshis as i64 };
+pub const DEFAULT_MAX_HTLCS: u16 = 50;
- if value_to_holder < 0 {
- assert!(self.is_outbound());
- total_fee_satoshis += (-value_to_holder) as u64;
- } else if value_to_counterparty < 0 {
- assert!(!self.is_outbound());
- total_fee_satoshis += (-value_to_counterparty) as u64;
- }
+pub(crate) fn commitment_tx_base_weight(opt_anchors: bool) -> u64 {
+ const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
+ const COMMITMENT_TX_BASE_ANCHOR_WEIGHT: u64 = 1124;
+ if opt_anchors { COMMITMENT_TX_BASE_ANCHOR_WEIGHT } else { COMMITMENT_TX_BASE_WEIGHT }
+}
- if skip_remote_output || value_to_counterparty as u64 <= self.context.holder_dust_limit_satoshis {
- value_to_counterparty = 0;
- }
+#[cfg(not(test))]
+const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
+#[cfg(test)]
+pub const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
- if value_to_holder as u64 <= self.context.holder_dust_limit_satoshis {
- value_to_holder = 0;
- }
+pub const ANCHOR_OUTPUT_VALUE_SATOSHI: u64 = 330;
- assert!(self.context.shutdown_scriptpubkey.is_some());
- let holder_shutdown_script = self.get_closing_scriptpubkey();
- let counterparty_shutdown_script = self.context.counterparty_shutdown_scriptpubkey.clone().unwrap();
- let funding_outpoint = self.funding_outpoint().into_bitcoin_outpoint();
+/// The percentage of the channel value `holder_max_htlc_value_in_flight_msat` used to be set to,
+/// before this was made configurable. The percentage was made configurable in LDK 0.0.107,
+/// although LDK 0.0.104+ enabled serialization of channels with a different value set for
+/// `holder_max_htlc_value_in_flight_msat`.
+pub const MAX_IN_FLIGHT_PERCENT_LEGACY: u8 = 10;
- let closing_transaction = ClosingTransaction::new(value_to_holder as u64, value_to_counterparty as u64, holder_shutdown_script, counterparty_shutdown_script, funding_outpoint);
- (closing_transaction, total_fee_satoshis)
- }
+/// Maximum `funding_satoshis` value according to the BOLT #2 specification, if
+/// `option_support_large_channel` (aka wumbo channels) is not supported.
+/// It's 2^24 - 1.
+pub const MAX_FUNDING_SATOSHIS_NO_WUMBO: u64 = (1 << 24) - 1;
- fn funding_outpoint(&self) -> OutPoint {
- self.context.channel_transaction_parameters.funding_outpoint.unwrap()
- }
+/// Total bitcoin supply in satoshis.
+pub const TOTAL_BITCOIN_SUPPLY_SATOSHIS: u64 = 21_000_000 * 1_0000_0000;
- #[inline]
- /// Creates a set of keys for build_commitment_transaction to generate a transaction which our
- /// counterparty will sign (ie DO NOT send signatures over a transaction created by this to
- /// our counterparty!)
- /// The result is a transaction which we can revoke broadcastership of (ie a "local" transaction)
- /// TODO Some magic rust shit to compile-time check this?
- fn build_holder_transaction_keys(&self, commitment_number: u64) -> TxCreationKeys {
- let per_commitment_point = self.context.holder_signer.get_per_commitment_point(commitment_number, &self.context.secp_ctx);
- let delayed_payment_base = &self.get_holder_pubkeys().delayed_payment_basepoint;
- let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
- let counterparty_pubkeys = self.get_counterparty_pubkeys();
+/// The maximum network dust limit for standard script formats. This currently represents the
+/// minimum output value for a P2SH output before Bitcoin Core 22 considers the entire
+/// transaction non-standard and thus refuses to relay it.
+/// We also use this as the maximum counterparty `dust_limit_satoshis` allowed, given many
+/// implementations use this value for their dust limit today.
+pub const MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS: u64 = 546;
- TxCreationKeys::derive_new(&self.context.secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint)
- }
+/// The maximum channel dust limit we will accept from our counterparty.
+pub const MAX_CHAN_DUST_LIMIT_SATOSHIS: u64 = MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS;
- #[inline]
- /// Creates a set of keys for build_commitment_transaction to generate a transaction which we
- /// will sign and send to our counterparty.
- /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
- fn build_remote_transaction_keys(&self) -> TxCreationKeys {
- //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
- //may see payments to it!
- let revocation_basepoint = &self.get_holder_pubkeys().revocation_basepoint;
- let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
- let counterparty_pubkeys = self.get_counterparty_pubkeys();
+/// The dust limit is used for both the commitment transaction outputs as well as the closing
+/// transactions. For cooperative closing transactions, we require segwit outputs, though accept
+/// *any* segwit scripts, which are allowed to be up to 42 bytes in length.
+/// In order to avoid having to concern ourselves with standardness during the closing process, we
+/// simply require our counterparty to use a dust limit which will leave any segwit output
+/// standard.
+/// See <https://github.com/lightning/bolts/issues/905> for more details.
+pub const MIN_CHAN_DUST_LIMIT_SATOSHIS: u64 = 354;
- TxCreationKeys::derive_new(&self.context.secp_ctx, &self.context.counterparty_cur_commitment_point.unwrap(), &counterparty_pubkeys.delayed_payment_basepoint, &counterparty_pubkeys.htlc_basepoint, revocation_basepoint, htlc_basepoint)
- }
+// Just a reasonable implementation-specific safe lower bound, higher than the dust limit.
+pub const MIN_THEIR_CHAN_RESERVE_SATOSHIS: u64 = 1000;
- /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
- /// pays to get_funding_redeemscript().to_v0_p2wsh()).
- /// Panics if called before accept_channel/new_from_req
- pub fn get_funding_redeemscript(&self) -> Script {
- make_funding_redeemscript(&self.get_holder_pubkeys().funding_pubkey, self.counterparty_funding_pubkey())
- }
+/// Used to return a simple Error back to ChannelManager. Will get converted to a
+/// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our
+/// channel_id in ChannelManager.
+pub(super) enum ChannelError {
+ Ignore(String),
+ Warn(String),
+ Close(String),
+}
- /// Claims an HTLC while we're disconnected from a peer, dropping the [`ChannelMonitorUpdate`]
- /// entirely.
- ///
- /// The [`ChannelMonitor`] for this channel MUST be updated out-of-band with the preimage
- /// provided (i.e. without calling [`crate::chain::Watch::update_channel`]).
- ///
- /// The HTLC claim will end up in the holding cell (because the caller must ensure the peer is
- /// disconnected).
- pub fn claim_htlc_while_disconnected_dropping_mon_update<L: Deref>
- (&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L)
- where L::Target: Logger {
- // Assert that we'll add the HTLC claim to the holding cell in `get_update_fulfill_htlc`
- // (see equivalent if condition there).
- assert!(self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32) != 0);
- let mon_update_id = self.context.latest_monitor_update_id; // Forget the ChannelMonitor update
- let fulfill_resp = self.get_update_fulfill_htlc(htlc_id_arg, payment_preimage_arg, logger);
- self.context.latest_monitor_update_id = mon_update_id;
- if let UpdateFulfillFetch::NewClaim { msg, .. } = fulfill_resp {
- assert!(msg.is_none()); // The HTLC must have ended up in the holding cell.
+impl fmt::Debug for ChannelError {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ match self {
+ &ChannelError::Ignore(ref e) => write!(f, "Ignore : {}", e),
+ &ChannelError::Warn(ref e) => write!(f, "Warn : {}", e),
+ &ChannelError::Close(ref e) => write!(f, "Close : {}", e),
}
}
+}
- fn get_update_fulfill_htlc<L: Deref>(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L) -> UpdateFulfillFetch where L::Target: Logger {
- // Either ChannelReady got set (which means it won't be unset) or there is no way any
- // caller thought we could have something claimed (cause we wouldn't have accepted in an
- // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
- // either.
- if (self.context.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
- panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
+macro_rules! secp_check {
+ ($res: expr, $err: expr) => {
+ match $res {
+ Ok(thing) => thing,
+ Err(_) => return Err(ChannelError::Close($err)),
}
- assert_eq!(self.context.channel_state & ChannelState::ShutdownComplete as u32, 0);
-
- let payment_hash_calc = PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).into_inner());
+ };
+}
- // ChannelManager may generate duplicate claims/fails due to HTLC update events from
- // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
- // these, but for now we just have to treat them as normal.
+impl<Signer: WriteableEcdsaChannelSigner> Channel<Signer> {
+ fn get_initial_channel_type(config: &UserConfig, their_features: &InitFeatures) -> ChannelTypeFeatures {
+ // The default channel type (ie the first one we try) depends on whether the channel is
+ // public - if it is, we just go with `only_static_remotekey` as it's the only option
+ // available. If it's private, we first try `scid_privacy` as it provides better privacy
+ // with no other changes, and fall back to `only_static_remotekey`.
+ let mut ret = ChannelTypeFeatures::only_static_remote_key();
+ if !config.channel_handshake_config.announced_channel &&
+ config.channel_handshake_config.negotiate_scid_privacy &&
+ their_features.supports_scid_privacy() {
+ ret.set_scid_privacy_required();
+ }
- let mut pending_idx = core::usize::MAX;
- let mut htlc_value_msat = 0;
- for (idx, htlc) in self.context.pending_inbound_htlcs.iter().enumerate() {
- if htlc.htlc_id == htlc_id_arg {
- assert_eq!(htlc.payment_hash, payment_hash_calc);
- match htlc.state {
- InboundHTLCState::Committed => {},
- InboundHTLCState::LocalRemoved(ref reason) => {
- if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
- } else {
- log_warn!(logger, "Have preimage and want to fulfill HTLC with payment hash {} we already failed against channel {}", log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id()));
- debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
- }
- return UpdateFulfillFetch::DuplicateClaim {};
- },
- _ => {
- debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
- // Don't return in release mode here so that we can update channel_monitor
- }
- }
- pending_idx = idx;
- htlc_value_msat = htlc.amount_msat;
- break;
+ // Optionally, if the user would like to negotiate the `anchors_zero_fee_htlc_tx` option, we
+ // set it now. If they don't understand it, we'll fall back to our default of
+ // `only_static_remotekey`.
+ #[cfg(anchors)]
+ { // Attributes are not allowed on if expressions on our current MSRV of 1.41.
+ if config.channel_handshake_config.negotiate_anchors_zero_fee_htlc_tx &&
+ their_features.supports_anchors_zero_fee_htlc_tx() {
+ ret.set_anchors_zero_fee_htlc_tx_required();
}
}
- if pending_idx == core::usize::MAX {
- #[cfg(any(test, fuzzing))]
- // If we failed to find an HTLC to fulfill, make sure it was previously fulfilled and
- // this is simply a duplicate claim, not previously failed and we lost funds.
- debug_assert!(self.context.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
- return UpdateFulfillFetch::DuplicateClaim {};
- }
- // Now update local state:
- //
- // We have to put the payment_preimage in the channel_monitor right away here to ensure we
- // can claim it even if the channel hits the chain before we see their next commitment.
- self.context.latest_monitor_update_id += 1;
- let monitor_update = ChannelMonitorUpdate {
- update_id: self.context.latest_monitor_update_id,
- updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
- payment_preimage: payment_preimage_arg.clone(),
- }],
- };
+ ret
+ }
- if (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 {
- // Note that this condition is the same as the assertion in
- // `claim_htlc_while_disconnected_dropping_mon_update` and must match exactly -
- // `claim_htlc_while_disconnected_dropping_mon_update` would not work correctly if we
- // do not not get into this branch.
- for pending_update in self.context.holding_cell_htlc_updates.iter() {
- match pending_update {
- &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
- if htlc_id_arg == htlc_id {
- // Make sure we don't leave latest_monitor_update_id incremented here:
- self.context.latest_monitor_update_id -= 1;
- #[cfg(any(test, fuzzing))]
- debug_assert!(self.context.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
- return UpdateFulfillFetch::DuplicateClaim {};
- }
- },
- &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
- if htlc_id_arg == htlc_id {
- log_warn!(logger, "Have preimage and want to fulfill HTLC with pending failure against channel {}", log_bytes!(self.channel_id()));
- // TODO: We may actually be able to switch to a fulfill here, though its
- // rare enough it may not be worth the complexity burden.
- debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
- return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
- }
- },
- _ => {}
- }
- }
- log_trace!(logger, "Adding HTLC claim to holding_cell in channel {}! Current state: {}", log_bytes!(self.channel_id()), self.context.channel_state);
- self.context.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
- payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
- });
- #[cfg(any(test, fuzzing))]
- self.context.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
- return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
+ /// If we receive an error message, it may only be a rejection of the channel type we tried,
+ /// not of our ability to open any channel at all. Thus, on error, we should first call this
+ /// and see if we get a new `OpenChannel` message, otherwise the channel is failed.
+ pub(crate) fn maybe_handle_error_without_close(&mut self, chain_hash: BlockHash) -> Result<msgs::OpenChannel, ()> {
+ if !self.context.is_outbound() || self.context.channel_state != ChannelState::OurInitSent as u32 { return Err(()); }
+ if self.context.channel_type == ChannelTypeFeatures::only_static_remote_key() {
+ // We've exhausted our options
+ return Err(());
}
- #[cfg(any(test, fuzzing))]
- self.context.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
-
- {
- let htlc = &mut self.context.pending_inbound_htlcs[pending_idx];
- if let InboundHTLCState::Committed = htlc.state {
- } else {
- debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
- return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
- }
- log_trace!(logger, "Upgrading HTLC {} to LocalRemoved with a Fulfill in channel {}!", log_bytes!(htlc.payment_hash.0), log_bytes!(self.context.channel_id));
- htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
+ // We support opening a few different types of channels. Try removing our additional
+ // features one by one until we've either arrived at our default or the counterparty has
+ // accepted one.
+ //
+ // Due to the order below, we may not negotiate `option_anchors_zero_fee_htlc_tx` if the
+ // counterparty doesn't support `option_scid_privacy`. Since `get_initial_channel_type`
+ // checks whether the counterparty supports every feature, this would only happen if the
+ // counterparty is advertising the feature, but rejecting channels proposing the feature for
+ // whatever reason.
+ if self.context.channel_type.supports_anchors_zero_fee_htlc_tx() {
+ self.context.channel_type.clear_anchors_zero_fee_htlc_tx();
+ assert!(self.context.channel_transaction_parameters.opt_non_zero_fee_anchors.is_none());
+ self.context.channel_transaction_parameters.opt_anchors = None;
+ } else if self.context.channel_type.supports_scid_privacy() {
+ self.context.channel_type.clear_scid_privacy();
+ } else {
+ self.context.channel_type = ChannelTypeFeatures::only_static_remote_key();
}
+ Ok(self.get_open_channel(chain_hash))
+ }
- UpdateFulfillFetch::NewClaim {
- monitor_update,
- htlc_value_msat,
- msg: Some(msgs::UpdateFulfillHTLC {
- channel_id: self.channel_id(),
- htlc_id: htlc_id_arg,
- payment_preimage: payment_preimage_arg,
- }),
+ // Constructors:
+ pub fn new_outbound<ES: Deref, SP: Deref, F: Deref>(
+ fee_estimator: &LowerBoundedFeeEstimator<F>, entropy_source: &ES, signer_provider: &SP, counterparty_node_id: PublicKey, their_features: &InitFeatures,
+ channel_value_satoshis: u64, push_msat: u64, user_id: u128, config: &UserConfig, current_chain_height: u32,
+ outbound_scid_alias: u64
+ ) -> Result<Channel<Signer>, APIError>
+ where ES::Target: EntropySource,
+ SP::Target: SignerProvider<Signer = Signer>,
+ F::Target: FeeEstimator,
+ {
+ let holder_selected_contest_delay = config.channel_handshake_config.our_to_self_delay;
+ let channel_keys_id = signer_provider.generate_channel_keys_id(false, channel_value_satoshis, user_id);
+ let holder_signer = signer_provider.derive_channel_signer(channel_value_satoshis, channel_keys_id);
+ let pubkeys = holder_signer.pubkeys().clone();
+
+ if !their_features.supports_wumbo() && channel_value_satoshis > MAX_FUNDING_SATOSHIS_NO_WUMBO {
+ return Err(APIError::APIMisuseError{err: format!("funding_value must not exceed {}, it was {}", MAX_FUNDING_SATOSHIS_NO_WUMBO, channel_value_satoshis)});
+ }
+ if channel_value_satoshis >= TOTAL_BITCOIN_SUPPLY_SATOSHIS {
+ return Err(APIError::APIMisuseError{err: format!("funding_value must be smaller than the total bitcoin supply, it was {}", channel_value_satoshis)});
+ }
+ let channel_value_msat = channel_value_satoshis * 1000;
+ if push_msat > channel_value_msat {
+ return Err(APIError::APIMisuseError { err: format!("Push value ({}) was larger than channel_value ({})", push_msat, channel_value_msat) });
+ }
+ if holder_selected_contest_delay < BREAKDOWN_TIMEOUT {
+ return Err(APIError::APIMisuseError {err: format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks", holder_selected_contest_delay)});
+ }
+ let holder_selected_channel_reserve_satoshis = get_holder_selected_channel_reserve_satoshis(channel_value_satoshis, config);
+ if holder_selected_channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
+ // Protocol level safety check in place, although it should never happen because
+ // of `MIN_THEIR_CHAN_RESERVE_SATOSHIS`
+ return Err(APIError::APIMisuseError { err: format!("Holder selected channel reserve below implemention limit dust_limit_satoshis {}", holder_selected_channel_reserve_satoshis) });
}
- }
- pub fn get_update_fulfill_htlc_and_commit<L: Deref>(&mut self, htlc_id: u64, payment_preimage: PaymentPreimage, logger: &L) -> UpdateFulfillCommitFetch where L::Target: Logger {
- let release_cs_monitor = self.context.pending_monitor_updates.iter().all(|upd| !upd.blocked);
- match self.get_update_fulfill_htlc(htlc_id, payment_preimage, logger) {
- UpdateFulfillFetch::NewClaim { mut monitor_update, htlc_value_msat, msg } => {
- // Even if we aren't supposed to let new monitor updates with commitment state
- // updates run, we still need to push the preimage ChannelMonitorUpdateStep no
- // matter what. Sadly, to push a new monitor update which flies before others
- // already queued, we have to insert it into the pending queue and update the
- // update_ids of all the following monitors.
- let unblocked_update_pos = if release_cs_monitor && msg.is_some() {
- let mut additional_update = self.build_commitment_no_status_check(logger);
- // build_commitment_no_status_check may bump latest_monitor_id but we want them
- // to be strictly increasing by one, so decrement it here.
- self.context.latest_monitor_update_id = monitor_update.update_id;
- monitor_update.updates.append(&mut additional_update.updates);
- self.context.pending_monitor_updates.push(PendingChannelMonitorUpdate {
- update: monitor_update, blocked: false,
- });
- self.context.pending_monitor_updates.len() - 1
- } else {
- let insert_pos = self.context.pending_monitor_updates.iter().position(|upd| upd.blocked)
- .unwrap_or(self.context.pending_monitor_updates.len());
- let new_mon_id = self.context.pending_monitor_updates.get(insert_pos)
- .map(|upd| upd.update.update_id).unwrap_or(monitor_update.update_id);
- monitor_update.update_id = new_mon_id;
- self.context.pending_monitor_updates.insert(insert_pos, PendingChannelMonitorUpdate {
- update: monitor_update, blocked: false,
- });
- for held_update in self.context.pending_monitor_updates.iter_mut().skip(insert_pos + 1) {
- held_update.update.update_id += 1;
- }
- if msg.is_some() {
- debug_assert!(false, "If there is a pending blocked monitor we should have MonitorUpdateInProgress set");
- let update = self.build_commitment_no_status_check(logger);
- self.context.pending_monitor_updates.push(PendingChannelMonitorUpdate {
- update, blocked: true,
- });
- }
- insert_pos
- };
- self.monitor_updating_paused(false, msg.is_some(), false, Vec::new(), Vec::new(), Vec::new());
- UpdateFulfillCommitFetch::NewClaim {
- monitor_update: &self.context.pending_monitor_updates.get(unblocked_update_pos)
- .expect("We just pushed the monitor update").update,
- htlc_value_msat,
- }
- },
- UpdateFulfillFetch::DuplicateClaim {} => UpdateFulfillCommitFetch::DuplicateClaim {},
+ let channel_type = Self::get_initial_channel_type(&config, their_features);
+ debug_assert!(channel_type.is_subset(&channelmanager::provided_channel_type_features(&config)));
+
+ let feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Normal);
+
+ let value_to_self_msat = channel_value_satoshis * 1000 - push_msat;
+ let commitment_tx_fee = commit_tx_fee_msat(feerate, MIN_AFFORDABLE_HTLC_COUNT, channel_type.requires_anchors_zero_fee_htlc_tx());
+ if value_to_self_msat < commitment_tx_fee {
+ return Err(APIError::APIMisuseError{ err: format!("Funding amount ({}) can't even pay fee for initial commitment transaction fee of {}.", value_to_self_msat / 1000, commitment_tx_fee / 1000) });
}
- }
- /// We can only have one resolution per HTLC. In some cases around reconnect, we may fulfill
- /// an HTLC more than once or fulfill once and then attempt to fail after reconnect. We cannot,
- /// however, fail more than once as we wait for an upstream failure to be irrevocably committed
- /// before we fail backwards.
- ///
- /// If we do fail twice, we `debug_assert!(false)` and return `Ok(None)`. Thus, this will always
- /// return `Ok(_)` if preconditions are met. In any case, `Err`s will only be
- /// [`ChannelError::Ignore`].
- pub fn queue_fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, logger: &L)
- -> Result<(), ChannelError> where L::Target: Logger {
- self.fail_htlc(htlc_id_arg, err_packet, true, logger)
- .map(|msg_opt| assert!(msg_opt.is_none(), "We forced holding cell?"))
- }
+ let mut secp_ctx = Secp256k1::new();
+ secp_ctx.seeded_randomize(&entropy_source.get_secure_random_bytes());
- /// We can only have one resolution per HTLC. In some cases around reconnect, we may fulfill
- /// an HTLC more than once or fulfill once and then attempt to fail after reconnect. We cannot,
- /// however, fail more than once as we wait for an upstream failure to be irrevocably committed
- /// before we fail backwards.
- ///
- /// If we do fail twice, we `debug_assert!(false)` and return `Ok(None)`. Thus, this will always
- /// return `Ok(_)` if preconditions are met. In any case, `Err`s will only be
- /// [`ChannelError::Ignore`].
- fn fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, mut force_holding_cell: bool, logger: &L)
- -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> where L::Target: Logger {
- if (self.context.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
- panic!("Was asked to fail an HTLC when channel was not in an operational state");
+ let shutdown_scriptpubkey = if config.channel_handshake_config.commit_upfront_shutdown_pubkey {
+ match signer_provider.get_shutdown_scriptpubkey() {
+ Ok(scriptpubkey) => Some(scriptpubkey),
+ Err(_) => return Err(APIError::ChannelUnavailable { err: "Failed to get shutdown scriptpubkey".to_owned()}),
+ }
+ } else { None };
+
+ if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey {
+ if !shutdown_scriptpubkey.is_compatible(&their_features) {
+ return Err(APIError::IncompatibleShutdownScript { script: shutdown_scriptpubkey.clone() });
+ }
}
- assert_eq!(self.context.channel_state & ChannelState::ShutdownComplete as u32, 0);
- // ChannelManager may generate duplicate claims/fails due to HTLC update events from
- // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
- // these, but for now we just have to treat them as normal.
+ let destination_script = match signer_provider.get_destination_script() {
+ Ok(script) => script,
+ Err(_) => return Err(APIError::ChannelUnavailable { err: "Failed to get destination script".to_owned()}),
+ };
+
+ let temporary_channel_id = entropy_source.get_secure_random_bytes();
+
+ Ok(Channel {
+ context: ChannelContext {
+ user_id,
+
+ config: LegacyChannelConfig {
+ options: config.channel_config.clone(),
+ announced_channel: config.channel_handshake_config.announced_channel,
+ commit_upfront_shutdown_pubkey: config.channel_handshake_config.commit_upfront_shutdown_pubkey,
+ },
+
+ prev_config: None,
+
+ inbound_handshake_limits_override: Some(config.channel_handshake_limits.clone()),
+
+ channel_id: temporary_channel_id,
+ temporary_channel_id: Some(temporary_channel_id),
+ channel_state: ChannelState::OurInitSent as u32,
+ announcement_sigs_state: AnnouncementSigsState::NotSent,
+ secp_ctx,
+ channel_value_satoshis,
+
+ latest_monitor_update_id: 0,
+
+ holder_signer,
+ shutdown_scriptpubkey,
+ destination_script,
+
+ cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
+ cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
+ value_to_self_msat,
+
+ pending_inbound_htlcs: Vec::new(),
+ pending_outbound_htlcs: Vec::new(),
+ holding_cell_htlc_updates: Vec::new(),
+ pending_update_fee: None,
+ holding_cell_update_fee: None,
+ next_holder_htlc_id: 0,
+ next_counterparty_htlc_id: 0,
+ update_time_counter: 1,
+
+ resend_order: RAACommitmentOrder::CommitmentFirst,
+
+ monitor_pending_channel_ready: false,
+ monitor_pending_revoke_and_ack: false,
+ monitor_pending_commitment_signed: false,
+ monitor_pending_forwards: Vec::new(),
+ monitor_pending_failures: Vec::new(),
+ monitor_pending_finalized_fulfills: Vec::new(),
+
+ #[cfg(debug_assertions)]
+ holder_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
+ #[cfg(debug_assertions)]
+ counterparty_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
+
+ last_sent_closing_fee: None,
+ pending_counterparty_closing_signed: None,
+ closing_fee_limits: None,
+ target_closing_feerate_sats_per_kw: None,
+
+ inbound_awaiting_accept: false,
+
+ funding_tx_confirmed_in: None,
+ funding_tx_confirmation_height: 0,
+ short_channel_id: None,
+ channel_creation_height: current_chain_height,
+
+ feerate_per_kw: feerate,
+ counterparty_dust_limit_satoshis: 0,
+ holder_dust_limit_satoshis: MIN_CHAN_DUST_LIMIT_SATOSHIS,
+ counterparty_max_htlc_value_in_flight_msat: 0,
+ holder_max_htlc_value_in_flight_msat: get_holder_max_htlc_value_in_flight_msat(channel_value_satoshis, &config.channel_handshake_config),
+ counterparty_selected_channel_reserve_satoshis: None, // Filled in in accept_channel
+ holder_selected_channel_reserve_satoshis,
+ counterparty_htlc_minimum_msat: 0,
+ holder_htlc_minimum_msat: if config.channel_handshake_config.our_htlc_minimum_msat == 0 { 1 } else { config.channel_handshake_config.our_htlc_minimum_msat },
+ counterparty_max_accepted_htlcs: 0,
+ holder_max_accepted_htlcs: cmp::min(config.channel_handshake_config.our_max_accepted_htlcs, MAX_HTLCS),
+ minimum_depth: None, // Filled in in accept_channel
+
+ counterparty_forwarding_info: None,
+
+ channel_transaction_parameters: ChannelTransactionParameters {
+ holder_pubkeys: pubkeys,
+ holder_selected_contest_delay: config.channel_handshake_config.our_to_self_delay,
+ is_outbound_from_holder: true,
+ counterparty_parameters: None,
+ funding_outpoint: None,
+ opt_anchors: if channel_type.requires_anchors_zero_fee_htlc_tx() { Some(()) } else { None },
+ opt_non_zero_fee_anchors: None
+ },
+ funding_transaction: None,
+
+ counterparty_cur_commitment_point: None,
+ counterparty_prev_commitment_point: None,
+ counterparty_node_id,
+
+ counterparty_shutdown_scriptpubkey: None,
+
+ commitment_secrets: CounterpartyCommitmentSecrets::new(),
+
+ channel_update_status: ChannelUpdateStatus::Enabled,
+ closing_signed_in_flight: false,
+
+ announcement_sigs: None,
+
+ #[cfg(any(test, fuzzing))]
+ next_local_commitment_tx_fee_info_cached: Mutex::new(None),
+ #[cfg(any(test, fuzzing))]
+ next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
+
+ workaround_lnd_bug_4006: None,
+ sent_message_awaiting_response: None,
+
+ latest_inbound_scid_alias: None,
+ outbound_scid_alias,
- let mut pending_idx = core::usize::MAX;
- for (idx, htlc) in self.context.pending_inbound_htlcs.iter().enumerate() {
- if htlc.htlc_id == htlc_id_arg {
- match htlc.state {
- InboundHTLCState::Committed => {},
- InboundHTLCState::LocalRemoved(ref reason) => {
- if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
- } else {
- debug_assert!(false, "Tried to fail an HTLC that was already failed");
- }
- return Ok(None);
- },
- _ => {
- debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
- return Err(ChannelError::Ignore(format!("Unable to find a pending HTLC which matched the given HTLC ID ({})", htlc.htlc_id)));
- }
- }
- pending_idx = idx;
+ channel_pending_event_emitted: false,
+ channel_ready_event_emitted: false,
+
+ #[cfg(any(test, fuzzing))]
+ historical_inbound_htlc_fulfills: HashSet::new(),
+
+ channel_type,
+ channel_keys_id,
+
+ pending_monitor_updates: Vec::new(),
}
- }
- if pending_idx == core::usize::MAX {
- #[cfg(any(test, fuzzing))]
- // If we failed to find an HTLC to fail, make sure it was previously fulfilled and this
- // is simply a duplicate fail, not previously failed and we failed-back too early.
- debug_assert!(self.context.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
- return Ok(None);
- }
+ })
+ }
- if (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 {
- debug_assert!(force_holding_cell, "!force_holding_cell is only called when emptying the holding cell, so we shouldn't end up back in it!");
- force_holding_cell = true;
+ fn check_remote_fee<F: Deref, L: Deref>(fee_estimator: &LowerBoundedFeeEstimator<F>,
+ feerate_per_kw: u32, cur_feerate_per_kw: Option<u32>, logger: &L)
+ -> Result<(), ChannelError> where F::Target: FeeEstimator, L::Target: Logger,
+ {
+ // We only bound the fee updates on the upper side to prevent completely absurd feerates,
+ // always accepting up to 25 sat/vByte or 10x our fee estimator's "High Priority" fee.
+ // We generally don't care too much if they set the feerate to something very high, but it
+ // could result in the channel being useless due to everything being dust.
+ let upper_limit = cmp::max(250 * 25,
+ fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64 * 10);
+ if feerate_per_kw as u64 > upper_limit {
+ return Err(ChannelError::Close(format!("Peer's feerate much too high. Actual: {}. Our expected upper limit: {}", feerate_per_kw, upper_limit)));
}
-
- // Now update local state:
- if force_holding_cell {
- for pending_update in self.context.holding_cell_htlc_updates.iter() {
- match pending_update {
- &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
- if htlc_id_arg == htlc_id {
- #[cfg(any(test, fuzzing))]
- debug_assert!(self.context.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
- return Ok(None);
- }
- },
- &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
- if htlc_id_arg == htlc_id {
- debug_assert!(false, "Tried to fail an HTLC that was already failed");
- return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
- }
- },
- _ => {}
+ let lower_limit = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Background);
+ // Some fee estimators round up to the next full sat/vbyte (ie 250 sats per kw), causing
+ // occasional issues with feerate disagreements between an initiator that wants a feerate
+ // of 1.1 sat/vbyte and a receiver that wants 1.1 rounded up to 2. Thus, we always add 250
+ // sat/kw before the comparison here.
+ if feerate_per_kw + 250 < lower_limit {
+ if let Some(cur_feerate) = cur_feerate_per_kw {
+ if feerate_per_kw > cur_feerate {
+ log_warn!(logger,
+ "Accepting feerate that may prevent us from closing this channel because it's higher than what we have now. Had {} s/kW, now {} s/kW.",
+ cur_feerate, feerate_per_kw);
+ return Ok(());
}
}
- log_trace!(logger, "Placing failure for HTLC ID {} in holding cell in channel {}.", htlc_id_arg, log_bytes!(self.channel_id()));
- self.context.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
- htlc_id: htlc_id_arg,
- err_packet,
- });
- return Ok(None);
+ return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {} (- 250)", feerate_per_kw, lower_limit)));
}
+ Ok(())
+ }
- log_trace!(logger, "Failing HTLC ID {} back with a update_fail_htlc message in channel {}.", htlc_id_arg, log_bytes!(self.channel_id()));
- {
- let htlc = &mut self.context.pending_inbound_htlcs[pending_idx];
- htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
- }
+ /// Creates a new channel from a remote sides' request for one.
+ /// Assumes chain_hash has already been checked and corresponds with what we expect!
+ pub fn new_from_req<ES: Deref, SP: Deref, F: Deref, L: Deref>(
+ fee_estimator: &LowerBoundedFeeEstimator<F>, entropy_source: &ES, signer_provider: &SP,
+ counterparty_node_id: PublicKey, our_supported_features: &ChannelTypeFeatures,
+ their_features: &InitFeatures, msg: &msgs::OpenChannel, user_id: u128, config: &UserConfig,
+ current_chain_height: u32, logger: &L, outbound_scid_alias: u64
+ ) -> Result<Channel<Signer>, ChannelError>
+ where ES::Target: EntropySource,
+ SP::Target: SignerProvider<Signer = Signer>,
+ F::Target: FeeEstimator,
+ L::Target: Logger,
+ {
+ let announced_channel = if (msg.channel_flags & 1) == 1 { true } else { false };
- Ok(Some(msgs::UpdateFailHTLC {
- channel_id: self.channel_id(),
- htlc_id: htlc_id_arg,
- reason: err_packet
- }))
- }
+ // First check the channel type is known, failing before we do anything else if we don't
+ // support this channel type.
+ let channel_type = if let Some(channel_type) = &msg.channel_type {
+ if channel_type.supports_any_optional_bits() {
+ return Err(ChannelError::Close("Channel Type field contained optional bits - this is not allowed".to_owned()));
+ }
- // Message handlers:
+ // We only support the channel types defined by the `ChannelManager` in
+ // `provided_channel_type_features`. The channel type must always support
+ // `static_remote_key`.
+ if !channel_type.requires_static_remote_key() {
+ return Err(ChannelError::Close("Channel Type was not understood - we require static remote key".to_owned()));
+ }
+ // Make sure we support all of the features behind the channel type.
+ if !channel_type.is_subset(our_supported_features) {
+ return Err(ChannelError::Close("Channel Type contains unsupported features".to_owned()));
+ }
+ if channel_type.requires_scid_privacy() && announced_channel {
+ return Err(ChannelError::Close("SCID Alias/Privacy Channel Type cannot be set on a public channel".to_owned()));
+ }
+ channel_type.clone()
+ } else {
+ let channel_type = ChannelTypeFeatures::from_init(&their_features);
+ if channel_type != ChannelTypeFeatures::only_static_remote_key() {
+ return Err(ChannelError::Close("Only static_remote_key is supported for non-negotiated channel types".to_owned()));
+ }
+ channel_type
+ };
+ let opt_anchors = channel_type.supports_anchors_zero_fee_htlc_tx();
- pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, default_limits: &ChannelHandshakeLimits, their_features: &InitFeatures) -> Result<(), ChannelError> {
- let peer_limits = if let Some(ref limits) = self.context.inbound_handshake_limits_override { limits } else { default_limits };
+ let channel_keys_id = signer_provider.generate_channel_keys_id(true, msg.funding_satoshis, user_id);
+ let holder_signer = signer_provider.derive_channel_signer(msg.funding_satoshis, channel_keys_id);
+ let pubkeys = holder_signer.pubkeys().clone();
+ let counterparty_pubkeys = ChannelPublicKeys {
+ funding_pubkey: msg.funding_pubkey,
+ revocation_basepoint: msg.revocation_basepoint,
+ payment_point: msg.payment_point,
+ delayed_payment_basepoint: msg.delayed_payment_basepoint,
+ htlc_basepoint: msg.htlc_basepoint
+ };
- // Check sanity of message fields:
- if !self.is_outbound() {
- return Err(ChannelError::Close("Got an accept_channel message from an inbound peer".to_owned()));
+ if config.channel_handshake_config.our_to_self_delay < BREAKDOWN_TIMEOUT {
+ return Err(ChannelError::Close(format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks. It must be greater than {}", config.channel_handshake_config.our_to_self_delay, BREAKDOWN_TIMEOUT)));
}
- if self.context.channel_state != ChannelState::OurInitSent as u32 {
- return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned()));
+
+ // Check sanity of message fields:
+ if msg.funding_satoshis > config.channel_handshake_limits.max_funding_satoshis {
+ return Err(ChannelError::Close(format!("Per our config, funding must be at most {}. It was {}", config.channel_handshake_limits.max_funding_satoshis, msg.funding_satoshis)));
}
- if msg.dust_limit_satoshis > 21000000 * 100000000 {
- return Err(ChannelError::Close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.dust_limit_satoshis)));
+ if msg.funding_satoshis >= TOTAL_BITCOIN_SUPPLY_SATOSHIS {
+ return Err(ChannelError::Close(format!("Funding must be smaller than the total bitcoin supply. It was {}", msg.funding_satoshis)));
}
- if msg.channel_reserve_satoshis > self.context.channel_value_satoshis {
- return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.context.channel_value_satoshis)));
+ if msg.channel_reserve_satoshis > msg.funding_satoshis {
+ return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must be not greater than funding_satoshis: {}", msg.channel_reserve_satoshis, msg.funding_satoshis)));
}
- if msg.dust_limit_satoshis > self.context.holder_selected_channel_reserve_satoshis {
- return Err(ChannelError::Close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.dust_limit_satoshis, self.context.holder_selected_channel_reserve_satoshis)));
+ let full_channel_value_msat = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
+ if msg.push_msat > full_channel_value_msat {
+ return Err(ChannelError::Close(format!("push_msat {} was larger than channel amount minus reserve ({})", msg.push_msat, full_channel_value_msat)));
}
- if msg.channel_reserve_satoshis > self.context.channel_value_satoshis - self.context.holder_selected_channel_reserve_satoshis {
- return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than channel value minus our reserve ({})",
- msg.channel_reserve_satoshis, self.context.channel_value_satoshis - self.context.holder_selected_channel_reserve_satoshis)));
+ if msg.dust_limit_satoshis > msg.funding_satoshis {
+ return Err(ChannelError::Close(format!("dust_limit_satoshis {} was larger than funding_satoshis {}. Peer never wants payout outputs?", msg.dust_limit_satoshis, msg.funding_satoshis)));
}
- let full_channel_value_msat = (self.context.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000;
if msg.htlc_minimum_msat >= full_channel_value_msat {
- return Err(ChannelError::Close(format!("Minimum htlc value ({}) is full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
+ return Err(ChannelError::Close(format!("Minimum htlc value ({}) was larger than full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
}
- let max_delay_acceptable = u16::min(peer_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
- if msg.to_self_delay > max_delay_acceptable {
- return Err(ChannelError::Close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_delay_acceptable, msg.to_self_delay)));
+ Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw, None, logger)?;
+
+ let max_counterparty_selected_contest_delay = u16::min(config.channel_handshake_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
+ if msg.to_self_delay > max_counterparty_selected_contest_delay {
+ return Err(ChannelError::Close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_counterparty_selected_contest_delay, msg.to_self_delay)));
}
if msg.max_accepted_htlcs < 1 {
return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
}
// Now check against optional parameters as set by config...
- if msg.htlc_minimum_msat > peer_limits.max_htlc_minimum_msat {
- return Err(ChannelError::Close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.htlc_minimum_msat, peer_limits.max_htlc_minimum_msat)));
+ if msg.funding_satoshis < config.channel_handshake_limits.min_funding_satoshis {
+ return Err(ChannelError::Close(format!("Funding satoshis ({}) is less than the user specified limit ({})", msg.funding_satoshis, config.channel_handshake_limits.min_funding_satoshis)));
}
- if msg.max_htlc_value_in_flight_msat < peer_limits.min_max_htlc_value_in_flight_msat {
- return Err(ChannelError::Close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.max_htlc_value_in_flight_msat, peer_limits.min_max_htlc_value_in_flight_msat)));
+ if msg.htlc_minimum_msat > config.channel_handshake_limits.max_htlc_minimum_msat {
+ return Err(ChannelError::Close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.htlc_minimum_msat, config.channel_handshake_limits.max_htlc_minimum_msat)));
}
- if msg.channel_reserve_satoshis > peer_limits.max_channel_reserve_satoshis {
- return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, peer_limits.max_channel_reserve_satoshis)));
+ if msg.max_htlc_value_in_flight_msat < config.channel_handshake_limits.min_max_htlc_value_in_flight_msat {
+ return Err(ChannelError::Close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.max_htlc_value_in_flight_msat, config.channel_handshake_limits.min_max_htlc_value_in_flight_msat)));
}
- if msg.max_accepted_htlcs < peer_limits.min_max_accepted_htlcs {
- return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, peer_limits.min_max_accepted_htlcs)));
+ if msg.channel_reserve_satoshis > config.channel_handshake_limits.max_channel_reserve_satoshis {
+ return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, config.channel_handshake_limits.max_channel_reserve_satoshis)));
+ }
+ if msg.max_accepted_htlcs < config.channel_handshake_limits.min_max_accepted_htlcs {
+ return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, config.channel_handshake_limits.min_max_accepted_htlcs)));
}
if msg.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
}
- if msg.dust_limit_satoshis > MAX_CHAN_DUST_LIMIT_SATOSHIS {
+ if msg.dust_limit_satoshis > MAX_CHAN_DUST_LIMIT_SATOSHIS {
return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
}
- if msg.minimum_depth > peer_limits.max_minimum_depth {
- return Err(ChannelError::Close(format!("We consider the minimum depth to be unreasonably large. Expected minimum: ({}). Actual: ({})", peer_limits.max_minimum_depth, msg.minimum_depth)));
+
+ // Convert things into internal flags and prep our state:
+
+ if config.channel_handshake_limits.force_announced_channel_preference {
+ if config.channel_handshake_config.announced_channel != announced_channel {
+ return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours".to_owned()));
+ }
+ }
+
+ let holder_selected_channel_reserve_satoshis = get_holder_selected_channel_reserve_satoshis(msg.funding_satoshis, config);
+ if holder_selected_channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
+ // Protocol level safety check in place, although it should never happen because
+ // of `MIN_THEIR_CHAN_RESERVE_SATOSHIS`
+ return Err(ChannelError::Close(format!("Suitable channel reserve not found. remote_channel_reserve was ({}). dust_limit_satoshis is ({}).", holder_selected_channel_reserve_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
+ }
+ if holder_selected_channel_reserve_satoshis * 1000 >= full_channel_value_msat {
+ return Err(ChannelError::Close(format!("Suitable channel reserve not found. remote_channel_reserve was ({})msats. Channel value is ({} - {})msats.", holder_selected_channel_reserve_satoshis * 1000, full_channel_value_msat, msg.push_msat)));
+ }
+ if msg.channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
+ log_debug!(logger, "channel_reserve_satoshis ({}) is smaller than our dust limit ({}). We can broadcast stale states without any risk, implying this channel is very insecure for our counterparty.",
+ msg.channel_reserve_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS);
+ }
+ if holder_selected_channel_reserve_satoshis < msg.dust_limit_satoshis {
+ return Err(ChannelError::Close(format!("Dust limit ({}) too high for the channel reserve we require the remote to keep ({})", msg.dust_limit_satoshis, holder_selected_channel_reserve_satoshis)));
+ }
+
+ // check if the funder's amount for the initial commitment tx is sufficient
+ // for full fee payment plus a few HTLCs to ensure the channel will be useful.
+ let funders_amount_msat = msg.funding_satoshis * 1000 - msg.push_msat;
+ let commitment_tx_fee = commit_tx_fee_msat(msg.feerate_per_kw, MIN_AFFORDABLE_HTLC_COUNT, opt_anchors) / 1000;
+ if funders_amount_msat / 1000 < commitment_tx_fee {
+ return Err(ChannelError::Close(format!("Funding amount ({} sats) can't even pay fee for initial commitment transaction fee of {} sats.", funders_amount_msat / 1000, commitment_tx_fee)));
}
- if let Some(ty) = &msg.channel_type {
- if *ty != self.context.channel_type {
- return Err(ChannelError::Close("Channel Type in accept_channel didn't match the one sent in open_channel.".to_owned()));
- }
- } else if their_features.supports_channel_type() {
- // Assume they've accepted the channel type as they said they understand it.
- } else {
- let channel_type = ChannelTypeFeatures::from_init(&their_features);
- if channel_type != ChannelTypeFeatures::only_static_remote_key() {
- return Err(ChannelError::Close("Only static_remote_key is supported for non-negotiated channel types".to_owned()));
- }
- self.context.channel_type = channel_type;
+ let to_remote_satoshis = funders_amount_msat / 1000 - commitment_tx_fee;
+ // While it's reasonable for us to not meet the channel reserve initially (if they don't
+ // want to push much to us), our counterparty should always have more than our reserve.
+ if to_remote_satoshis < holder_selected_channel_reserve_satoshis {
+ return Err(ChannelError::Close("Insufficient funding amount for initial reserve".to_owned()));
}
let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
None
} else {
if !script::is_bolt2_compliant(&script, their_features) {
- return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)));
+ return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)))
}
Some(script.clone())
}
}
} else { None };
- self.context.counterparty_dust_limit_satoshis = msg.dust_limit_satoshis;
- self.context.counterparty_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.context.channel_value_satoshis * 1000);
- self.context.counterparty_selected_channel_reserve_satoshis = Some(msg.channel_reserve_satoshis);
- self.context.counterparty_htlc_minimum_msat = msg.htlc_minimum_msat;
- self.context.counterparty_max_accepted_htlcs = msg.max_accepted_htlcs;
+ let shutdown_scriptpubkey = if config.channel_handshake_config.commit_upfront_shutdown_pubkey {
+ match signer_provider.get_shutdown_scriptpubkey() {
+ Ok(scriptpubkey) => Some(scriptpubkey),
+ Err(_) => return Err(ChannelError::Close("Failed to get upfront shutdown scriptpubkey".to_owned())),
+ }
+ } else { None };
- if peer_limits.trust_own_funding_0conf {
- self.context.minimum_depth = Some(msg.minimum_depth);
- } else {
- self.context.minimum_depth = Some(cmp::max(1, msg.minimum_depth));
+ if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey {
+ if !shutdown_scriptpubkey.is_compatible(&their_features) {
+ return Err(ChannelError::Close(format!("Provided a scriptpubkey format not accepted by peer: {}", shutdown_scriptpubkey)));
+ }
}
- let counterparty_pubkeys = ChannelPublicKeys {
- funding_pubkey: msg.funding_pubkey,
- revocation_basepoint: msg.revocation_basepoint,
- payment_point: msg.payment_point,
- delayed_payment_basepoint: msg.delayed_payment_basepoint,
- htlc_basepoint: msg.htlc_basepoint
+ let destination_script = match signer_provider.get_destination_script() {
+ Ok(script) => script,
+ Err(_) => return Err(ChannelError::Close("Failed to get destination script".to_owned())),
};
- self.context.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
- selected_contest_delay: msg.to_self_delay,
- pubkeys: counterparty_pubkeys,
- });
+ let mut secp_ctx = Secp256k1::new();
+ secp_ctx.seeded_randomize(&entropy_source.get_secure_random_bytes());
- self.context.counterparty_cur_commitment_point = Some(msg.first_per_commitment_point);
- self.context.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
+ let chan = Channel {
+ context: ChannelContext {
+ user_id,
- self.context.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
- self.context.inbound_handshake_limits_override = None; // We're done enforcing limits on our peer's handshake now.
+ config: LegacyChannelConfig {
+ options: config.channel_config.clone(),
+ announced_channel,
+ commit_upfront_shutdown_pubkey: config.channel_handshake_config.commit_upfront_shutdown_pubkey,
+ },
- Ok(())
- }
+ prev_config: None,
- fn funding_created_signature<L: Deref>(&mut self, sig: &Signature, logger: &L) -> Result<(Txid, CommitmentTransaction, Signature), ChannelError> where L::Target: Logger {
- let funding_script = self.get_funding_redeemscript();
+ inbound_handshake_limits_override: None,
- let keys = self.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
- let initial_commitment_tx = self.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &keys, true, false, logger).tx;
- {
- let trusted_tx = initial_commitment_tx.trust();
- let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
- let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.context.channel_value_satoshis);
- // They sign the holder commitment transaction...
- log_trace!(logger, "Checking funding_created tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} for channel {}.",
- log_bytes!(sig.serialize_compact()[..]), log_bytes!(self.counterparty_funding_pubkey().serialize()),
- encode::serialize_hex(&initial_commitment_bitcoin_tx.transaction), log_bytes!(sighash[..]),
- encode::serialize_hex(&funding_script), log_bytes!(self.channel_id()));
- secp_check!(self.context.secp_ctx.verify_ecdsa(&sighash, &sig, self.counterparty_funding_pubkey()), "Invalid funding_created signature from peer".to_owned());
- }
+ temporary_channel_id: Some(msg.temporary_channel_id),
+ channel_id: msg.temporary_channel_id,
+ channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
+ announcement_sigs_state: AnnouncementSigsState::NotSent,
+ secp_ctx,
- let counterparty_keys = self.build_remote_transaction_keys();
- let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.context.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).tx;
+ latest_monitor_update_id: 0,
- let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
- let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
- log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
- log_bytes!(self.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
+ holder_signer,
+ shutdown_scriptpubkey,
+ destination_script,
- let counterparty_signature = self.context.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, Vec::new(), &self.context.secp_ctx)
- .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0;
+ cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
+ cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
+ value_to_self_msat: msg.push_msat,
- // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
- Ok((counterparty_initial_bitcoin_tx.txid, initial_commitment_tx, counterparty_signature))
+ pending_inbound_htlcs: Vec::new(),
+ pending_outbound_htlcs: Vec::new(),
+ holding_cell_htlc_updates: Vec::new(),
+ pending_update_fee: None,
+ holding_cell_update_fee: None,
+ next_holder_htlc_id: 0,
+ next_counterparty_htlc_id: 0,
+ update_time_counter: 1,
+
+ resend_order: RAACommitmentOrder::CommitmentFirst,
+
+ monitor_pending_channel_ready: false,
+ monitor_pending_revoke_and_ack: false,
+ monitor_pending_commitment_signed: false,
+ monitor_pending_forwards: Vec::new(),
+ monitor_pending_failures: Vec::new(),
+ monitor_pending_finalized_fulfills: Vec::new(),
+
+ #[cfg(debug_assertions)]
+ holder_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
+ #[cfg(debug_assertions)]
+ counterparty_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
+
+ last_sent_closing_fee: None,
+ pending_counterparty_closing_signed: None,
+ closing_fee_limits: None,
+ target_closing_feerate_sats_per_kw: None,
+
+ inbound_awaiting_accept: true,
+
+ funding_tx_confirmed_in: None,
+ funding_tx_confirmation_height: 0,
+ short_channel_id: None,
+ channel_creation_height: current_chain_height,
+
+ feerate_per_kw: msg.feerate_per_kw,
+ channel_value_satoshis: msg.funding_satoshis,
+ counterparty_dust_limit_satoshis: msg.dust_limit_satoshis,
+ holder_dust_limit_satoshis: MIN_CHAN_DUST_LIMIT_SATOSHIS,
+ counterparty_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
+ holder_max_htlc_value_in_flight_msat: get_holder_max_htlc_value_in_flight_msat(msg.funding_satoshis, &config.channel_handshake_config),
+ counterparty_selected_channel_reserve_satoshis: Some(msg.channel_reserve_satoshis),
+ holder_selected_channel_reserve_satoshis,
+ counterparty_htlc_minimum_msat: msg.htlc_minimum_msat,
+ holder_htlc_minimum_msat: if config.channel_handshake_config.our_htlc_minimum_msat == 0 { 1 } else { config.channel_handshake_config.our_htlc_minimum_msat },
+ counterparty_max_accepted_htlcs: msg.max_accepted_htlcs,
+ holder_max_accepted_htlcs: cmp::min(config.channel_handshake_config.our_max_accepted_htlcs, MAX_HTLCS),
+ minimum_depth: Some(cmp::max(config.channel_handshake_config.minimum_depth, 1)),
+
+ counterparty_forwarding_info: None,
+
+ channel_transaction_parameters: ChannelTransactionParameters {
+ holder_pubkeys: pubkeys,
+ holder_selected_contest_delay: config.channel_handshake_config.our_to_self_delay,
+ is_outbound_from_holder: false,
+ counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
+ selected_contest_delay: msg.to_self_delay,
+ pubkeys: counterparty_pubkeys,
+ }),
+ funding_outpoint: None,
+ opt_anchors: if opt_anchors { Some(()) } else { None },
+ opt_non_zero_fee_anchors: None
+ },
+ funding_transaction: None,
+
+ counterparty_cur_commitment_point: Some(msg.first_per_commitment_point),
+ counterparty_prev_commitment_point: None,
+ counterparty_node_id,
+
+ counterparty_shutdown_scriptpubkey,
+
+ commitment_secrets: CounterpartyCommitmentSecrets::new(),
+
+ channel_update_status: ChannelUpdateStatus::Enabled,
+ closing_signed_in_flight: false,
+
+ announcement_sigs: None,
+
+ #[cfg(any(test, fuzzing))]
+ next_local_commitment_tx_fee_info_cached: Mutex::new(None),
+ #[cfg(any(test, fuzzing))]
+ next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
+
+ workaround_lnd_bug_4006: None,
+ sent_message_awaiting_response: None,
+
+ latest_inbound_scid_alias: None,
+ outbound_scid_alias,
+
+ channel_pending_event_emitted: false,
+ channel_ready_event_emitted: false,
+
+ #[cfg(any(test, fuzzing))]
+ historical_inbound_htlc_fulfills: HashSet::new(),
+
+ channel_type,
+ channel_keys_id,
+
+ pending_monitor_updates: Vec::new(),
+ }
+ };
+
+ Ok(chan)
}
- fn counterparty_funding_pubkey(&self) -> &PublicKey {
- &self.get_counterparty_pubkeys().funding_pubkey
+ #[inline]
+ fn get_closing_scriptpubkey(&self) -> Script {
+ // The shutdown scriptpubkey is set on channel opening when option_upfront_shutdown_script
+ // is signaled. Otherwise, it is set when sending a shutdown message. Calling this method
+ // outside of those situations will fail.
+ self.context.shutdown_scriptpubkey.clone().unwrap().into_inner()
}
- pub fn funding_created<SP: Deref, L: Deref>(
- &mut self, msg: &msgs::FundingCreated, best_block: BestBlock, signer_provider: &SP, logger: &L
- ) -> Result<(msgs::FundingSigned, ChannelMonitor<Signer>), ChannelError>
- where
- SP::Target: SignerProvider<Signer = Signer>,
- L::Target: Logger
- {
- if self.is_outbound() {
- return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned()));
+ #[inline]
+ fn get_closing_transaction_weight(&self, a_scriptpubkey: Option<&Script>, b_scriptpubkey: Option<&Script>) -> u64 {
+ let mut ret =
+ (4 + // version
+ 1 + // input count
+ 36 + // prevout
+ 1 + // script length (0)
+ 4 + // sequence
+ 1 + // output count
+ 4 // lock time
+ )*4 + // * 4 for non-witness parts
+ 2 + // witness marker and flag
+ 1 + // witness element count
+ 4 + // 4 element lengths (2 sigs, multisig dummy, and witness script)
+ self.context.get_funding_redeemscript().len() as u64 + // funding witness script
+ 2*(1 + 71); // two signatures + sighash type flags
+ if let Some(spk) = a_scriptpubkey {
+ ret += ((8+1) + // output values and script length
+ spk.len() as u64) * 4; // scriptpubkey and witness multiplier
}
- if self.context.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
- // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
- // remember the channel, so it's safe to just send an error_message here and drop the
- // channel.
- return Err(ChannelError::Close("Received funding_created after we got the channel!".to_owned()));
+ if let Some(spk) = b_scriptpubkey {
+ ret += ((8+1) + // output values and script length
+ spk.len() as u64) * 4; // scriptpubkey and witness multiplier
}
- if self.context.inbound_awaiting_accept {
- return Err(ChannelError::Close("FundingCreated message received before the channel was accepted".to_owned()));
+ ret
+ }
+
+ #[inline]
+ fn build_closing_transaction(&self, proposed_total_fee_satoshis: u64, skip_remote_output: bool) -> (ClosingTransaction, u64) {
+ assert!(self.context.pending_inbound_htlcs.is_empty());
+ assert!(self.context.pending_outbound_htlcs.is_empty());
+ assert!(self.context.pending_update_fee.is_none());
+
+ let mut total_fee_satoshis = proposed_total_fee_satoshis;
+ let mut value_to_holder: i64 = (self.context.value_to_self_msat as i64) / 1000 - if self.context.is_outbound() { total_fee_satoshis as i64 } else { 0 };
+ let mut value_to_counterparty: i64 = ((self.context.channel_value_satoshis * 1000 - self.context.value_to_self_msat) as i64 / 1000) - if self.context.is_outbound() { 0 } else { total_fee_satoshis as i64 };
+
+ if value_to_holder < 0 {
+ assert!(self.context.is_outbound());
+ total_fee_satoshis += (-value_to_holder) as u64;
+ } else if value_to_counterparty < 0 {
+ assert!(!self.context.is_outbound());
+ total_fee_satoshis += (-value_to_counterparty) as u64;
}
- if self.context.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
- self.context.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
- self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
- panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
+
+ if skip_remote_output || value_to_counterparty as u64 <= self.context.holder_dust_limit_satoshis {
+ value_to_counterparty = 0;
}
- let funding_txo = OutPoint { txid: msg.funding_txid, index: msg.funding_output_index };
- self.context.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
- // This is an externally observable change before we finish all our checks. In particular
- // funding_created_signature may fail.
- self.context.holder_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
+ if value_to_holder as u64 <= self.context.holder_dust_limit_satoshis {
+ value_to_holder = 0;
+ }
- let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
- Ok(res) => res,
- Err(ChannelError::Close(e)) => {
- self.context.channel_transaction_parameters.funding_outpoint = None;
- return Err(ChannelError::Close(e));
- },
- Err(e) => {
- // The only error we know how to handle is ChannelError::Close, so we fall over here
- // to make sure we don't continue with an inconsistent state.
- panic!("unexpected error type from funding_created_signature {:?}", e);
- }
- };
+ assert!(self.context.shutdown_scriptpubkey.is_some());
+ let holder_shutdown_script = self.get_closing_scriptpubkey();
+ let counterparty_shutdown_script = self.context.counterparty_shutdown_scriptpubkey.clone().unwrap();
+ let funding_outpoint = self.funding_outpoint().into_bitcoin_outpoint();
- let holder_commitment_tx = HolderCommitmentTransaction::new(
- initial_commitment_tx,
- msg.signature,
- Vec::new(),
- &self.get_holder_pubkeys().funding_pubkey,
- self.counterparty_funding_pubkey()
- );
+ let closing_transaction = ClosingTransaction::new(value_to_holder as u64, value_to_counterparty as u64, holder_shutdown_script, counterparty_shutdown_script, funding_outpoint);
+ (closing_transaction, total_fee_satoshis)
+ }
- self.context.holder_signer.validate_holder_commitment(&holder_commitment_tx, Vec::new())
- .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
+ fn funding_outpoint(&self) -> OutPoint {
+ self.context.channel_transaction_parameters.funding_outpoint.unwrap()
+ }
- // Now that we're past error-generating stuff, update our local state:
+ /// Claims an HTLC while we're disconnected from a peer, dropping the [`ChannelMonitorUpdate`]
+ /// entirely.
+ ///
+ /// The [`ChannelMonitor`] for this channel MUST be updated out-of-band with the preimage
+ /// provided (i.e. without calling [`crate::chain::Watch::update_channel`]).
+ ///
+ /// The HTLC claim will end up in the holding cell (because the caller must ensure the peer is
+ /// disconnected).
+ pub fn claim_htlc_while_disconnected_dropping_mon_update<L: Deref>
+ (&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L)
+ where L::Target: Logger {
+ // Assert that we'll add the HTLC claim to the holding cell in `get_update_fulfill_htlc`
+ // (see equivalent if condition there).
+ assert!(self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32) != 0);
+ let mon_update_id = self.context.latest_monitor_update_id; // Forget the ChannelMonitor update
+ let fulfill_resp = self.get_update_fulfill_htlc(htlc_id_arg, payment_preimage_arg, logger);
+ self.context.latest_monitor_update_id = mon_update_id;
+ if let UpdateFulfillFetch::NewClaim { msg, .. } = fulfill_resp {
+ assert!(msg.is_none()); // The HTLC must have ended up in the holding cell.
+ }
+ }
- let funding_redeemscript = self.get_funding_redeemscript();
- let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
- let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
- let shutdown_script = self.context.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
- let mut monitor_signer = signer_provider.derive_channel_signer(self.context.channel_value_satoshis, self.context.channel_keys_id);
- monitor_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
- let channel_monitor = ChannelMonitor::new(self.context.secp_ctx.clone(), monitor_signer,
- shutdown_script, self.get_holder_selected_contest_delay(),
- &self.context.destination_script, (funding_txo, funding_txo_script.clone()),
- &self.context.channel_transaction_parameters,
- funding_redeemscript.clone(), self.context.channel_value_satoshis,
- obscure_factor,
- holder_commitment_tx, best_block, self.context.counterparty_node_id);
+ fn get_update_fulfill_htlc<L: Deref>(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L) -> UpdateFulfillFetch where L::Target: Logger {
+ // Either ChannelReady got set (which means it won't be unset) or there is no way any
+ // caller thought we could have something claimed (cause we wouldn't have accepted in an
+ // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
+ // either.
+ if (self.context.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
+ panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
+ }
+ assert_eq!(self.context.channel_state & ChannelState::ShutdownComplete as u32, 0);
- channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_commitment_txid, Vec::new(), self.context.cur_counterparty_commitment_transaction_number, self.context.counterparty_cur_commitment_point.unwrap(), logger);
+ let payment_hash_calc = PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).into_inner());
- self.context.channel_state = ChannelState::FundingSent as u32;
- self.context.channel_id = funding_txo.to_channel_id();
- self.context.cur_counterparty_commitment_transaction_number -= 1;
- self.context.cur_holder_commitment_transaction_number -= 1;
+ // ChannelManager may generate duplicate claims/fails due to HTLC update events from
+ // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
+ // these, but for now we just have to treat them as normal.
- log_info!(logger, "Generated funding_signed for peer for channel {}", log_bytes!(self.channel_id()));
+ let mut pending_idx = core::usize::MAX;
+ let mut htlc_value_msat = 0;
+ for (idx, htlc) in self.context.pending_inbound_htlcs.iter().enumerate() {
+ if htlc.htlc_id == htlc_id_arg {
+ assert_eq!(htlc.payment_hash, payment_hash_calc);
+ match htlc.state {
+ InboundHTLCState::Committed => {},
+ InboundHTLCState::LocalRemoved(ref reason) => {
+ if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
+ } else {
+ log_warn!(logger, "Have preimage and want to fulfill HTLC with payment hash {} we already failed against channel {}", log_bytes!(htlc.payment_hash.0), log_bytes!(self.context.channel_id()));
+ debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
+ }
+ return UpdateFulfillFetch::DuplicateClaim {};
+ },
+ _ => {
+ debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
+ // Don't return in release mode here so that we can update channel_monitor
+ }
+ }
+ pending_idx = idx;
+ htlc_value_msat = htlc.amount_msat;
+ break;
+ }
+ }
+ if pending_idx == core::usize::MAX {
+ #[cfg(any(test, fuzzing))]
+ // If we failed to find an HTLC to fulfill, make sure it was previously fulfilled and
+ // this is simply a duplicate claim, not previously failed and we lost funds.
+ debug_assert!(self.context.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
+ return UpdateFulfillFetch::DuplicateClaim {};
+ }
- let need_channel_ready = self.check_get_channel_ready(0).is_some();
- self.monitor_updating_paused(false, false, need_channel_ready, Vec::new(), Vec::new(), Vec::new());
+ // Now update local state:
+ //
+ // We have to put the payment_preimage in the channel_monitor right away here to ensure we
+ // can claim it even if the channel hits the chain before we see their next commitment.
+ self.context.latest_monitor_update_id += 1;
+ let monitor_update = ChannelMonitorUpdate {
+ update_id: self.context.latest_monitor_update_id,
+ updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
+ payment_preimage: payment_preimage_arg.clone(),
+ }],
+ };
- Ok((msgs::FundingSigned {
- channel_id: self.context.channel_id,
- signature,
- #[cfg(taproot)]
- partial_signature_with_nonce: None,
- }, channel_monitor))
- }
+ if (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 {
+ // Note that this condition is the same as the assertion in
+ // `claim_htlc_while_disconnected_dropping_mon_update` and must match exactly -
+ // `claim_htlc_while_disconnected_dropping_mon_update` would not work correctly if we
+ // do not not get into this branch.
+ for pending_update in self.context.holding_cell_htlc_updates.iter() {
+ match pending_update {
+ &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
+ if htlc_id_arg == htlc_id {
+ // Make sure we don't leave latest_monitor_update_id incremented here:
+ self.context.latest_monitor_update_id -= 1;
+ #[cfg(any(test, fuzzing))]
+ debug_assert!(self.context.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
+ return UpdateFulfillFetch::DuplicateClaim {};
+ }
+ },
+ &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
+ if htlc_id_arg == htlc_id {
+ log_warn!(logger, "Have preimage and want to fulfill HTLC with pending failure against channel {}", log_bytes!(self.context.channel_id()));
+ // TODO: We may actually be able to switch to a fulfill here, though its
+ // rare enough it may not be worth the complexity burden.
+ debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
+ return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
+ }
+ },
+ _ => {}
+ }
+ }
+ log_trace!(logger, "Adding HTLC claim to holding_cell in channel {}! Current state: {}", log_bytes!(self.context.channel_id()), self.context.channel_state);
+ self.context.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
+ payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
+ });
+ #[cfg(any(test, fuzzing))]
+ self.context.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
+ return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
+ }
+ #[cfg(any(test, fuzzing))]
+ self.context.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
- /// Handles a funding_signed message from the remote end.
- /// If this call is successful, broadcast the funding transaction (and not before!)
- pub fn funding_signed<SP: Deref, L: Deref>(
- &mut self, msg: &msgs::FundingSigned, best_block: BestBlock, signer_provider: &SP, logger: &L
- ) -> Result<ChannelMonitor<Signer>, ChannelError>
- where
- SP::Target: SignerProvider<Signer = Signer>,
- L::Target: Logger
- {
- if !self.is_outbound() {
- return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
+ {
+ let htlc = &mut self.context.pending_inbound_htlcs[pending_idx];
+ if let InboundHTLCState::Committed = htlc.state {
+ } else {
+ debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
+ return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
+ }
+ log_trace!(logger, "Upgrading HTLC {} to LocalRemoved with a Fulfill in channel {}!", log_bytes!(htlc.payment_hash.0), log_bytes!(self.context.channel_id));
+ htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
}
- if self.context.channel_state & !(ChannelState::MonitorUpdateInProgress as u32) != ChannelState::FundingCreated as u32 {
- return Err(ChannelError::Close("Received funding_signed in strange state!".to_owned()));
+
+ UpdateFulfillFetch::NewClaim {
+ monitor_update,
+ htlc_value_msat,
+ msg: Some(msgs::UpdateFulfillHTLC {
+ channel_id: self.context.channel_id(),
+ htlc_id: htlc_id_arg,
+ payment_preimage: payment_preimage_arg,
+ }),
}
- if self.context.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
- self.context.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
- self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
- panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
+ }
+
+ pub fn get_update_fulfill_htlc_and_commit<L: Deref>(&mut self, htlc_id: u64, payment_preimage: PaymentPreimage, logger: &L) -> UpdateFulfillCommitFetch where L::Target: Logger {
+ let release_cs_monitor = self.context.pending_monitor_updates.iter().all(|upd| !upd.blocked);
+ match self.get_update_fulfill_htlc(htlc_id, payment_preimage, logger) {
+ UpdateFulfillFetch::NewClaim { mut monitor_update, htlc_value_msat, msg } => {
+ // Even if we aren't supposed to let new monitor updates with commitment state
+ // updates run, we still need to push the preimage ChannelMonitorUpdateStep no
+ // matter what. Sadly, to push a new monitor update which flies before others
+ // already queued, we have to insert it into the pending queue and update the
+ // update_ids of all the following monitors.
+ let unblocked_update_pos = if release_cs_monitor && msg.is_some() {
+ let mut additional_update = self.build_commitment_no_status_check(logger);
+ // build_commitment_no_status_check may bump latest_monitor_id but we want them
+ // to be strictly increasing by one, so decrement it here.
+ self.context.latest_monitor_update_id = monitor_update.update_id;
+ monitor_update.updates.append(&mut additional_update.updates);
+ self.context.pending_monitor_updates.push(PendingChannelMonitorUpdate {
+ update: monitor_update, blocked: false,
+ });
+ self.context.pending_monitor_updates.len() - 1
+ } else {
+ let insert_pos = self.context.pending_monitor_updates.iter().position(|upd| upd.blocked)
+ .unwrap_or(self.context.pending_monitor_updates.len());
+ let new_mon_id = self.context.pending_monitor_updates.get(insert_pos)
+ .map(|upd| upd.update.update_id).unwrap_or(monitor_update.update_id);
+ monitor_update.update_id = new_mon_id;
+ self.context.pending_monitor_updates.insert(insert_pos, PendingChannelMonitorUpdate {
+ update: monitor_update, blocked: false,
+ });
+ for held_update in self.context.pending_monitor_updates.iter_mut().skip(insert_pos + 1) {
+ held_update.update.update_id += 1;
+ }
+ if msg.is_some() {
+ debug_assert!(false, "If there is a pending blocked monitor we should have MonitorUpdateInProgress set");
+ let update = self.build_commitment_no_status_check(logger);
+ self.context.pending_monitor_updates.push(PendingChannelMonitorUpdate {
+ update, blocked: true,
+ });
+ }
+ insert_pos
+ };
+ self.monitor_updating_paused(false, msg.is_some(), false, Vec::new(), Vec::new(), Vec::new());
+ UpdateFulfillCommitFetch::NewClaim {
+ monitor_update: &self.context.pending_monitor_updates.get(unblocked_update_pos)
+ .expect("We just pushed the monitor update").update,
+ htlc_value_msat,
+ }
+ },
+ UpdateFulfillFetch::DuplicateClaim {} => UpdateFulfillCommitFetch::DuplicateClaim {},
}
+ }
- let funding_script = self.get_funding_redeemscript();
+ /// We can only have one resolution per HTLC. In some cases around reconnect, we may fulfill
+ /// an HTLC more than once or fulfill once and then attempt to fail after reconnect. We cannot,
+ /// however, fail more than once as we wait for an upstream failure to be irrevocably committed
+ /// before we fail backwards.
+ ///
+ /// If we do fail twice, we `debug_assert!(false)` and return `Ok(None)`. Thus, this will always
+ /// return `Ok(_)` if preconditions are met. In any case, `Err`s will only be
+ /// [`ChannelError::Ignore`].
+ pub fn queue_fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, logger: &L)
+ -> Result<(), ChannelError> where L::Target: Logger {
+ self.fail_htlc(htlc_id_arg, err_packet, true, logger)
+ .map(|msg_opt| assert!(msg_opt.is_none(), "We forced holding cell?"))
+ }
- let counterparty_keys = self.build_remote_transaction_keys();
- let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.context.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).tx;
- let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
- let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
+ /// We can only have one resolution per HTLC. In some cases around reconnect, we may fulfill
+ /// an HTLC more than once or fulfill once and then attempt to fail after reconnect. We cannot,
+ /// however, fail more than once as we wait for an upstream failure to be irrevocably committed
+ /// before we fail backwards.
+ ///
+ /// If we do fail twice, we `debug_assert!(false)` and return `Ok(None)`. Thus, this will always
+ /// return `Ok(_)` if preconditions are met. In any case, `Err`s will only be
+ /// [`ChannelError::Ignore`].
+ fn fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, mut force_holding_cell: bool, logger: &L)
+ -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> where L::Target: Logger {
+ if (self.context.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
+ panic!("Was asked to fail an HTLC when channel was not in an operational state");
+ }
+ assert_eq!(self.context.channel_state & ChannelState::ShutdownComplete as u32, 0);
- log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
- log_bytes!(self.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
+ // ChannelManager may generate duplicate claims/fails due to HTLC update events from
+ // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
+ // these, but for now we just have to treat them as normal.
- let holder_signer = self.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
- let initial_commitment_tx = self.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &holder_signer, true, false, logger).tx;
- {
- let trusted_tx = initial_commitment_tx.trust();
- let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
- let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.context.channel_value_satoshis);
- // They sign our commitment transaction, allowing us to broadcast the tx if we wish.
- if let Err(_) = self.context.secp_ctx.verify_ecdsa(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
- return Err(ChannelError::Close("Invalid funding_signed signature from peer".to_owned()));
+ let mut pending_idx = core::usize::MAX;
+ for (idx, htlc) in self.context.pending_inbound_htlcs.iter().enumerate() {
+ if htlc.htlc_id == htlc_id_arg {
+ match htlc.state {
+ InboundHTLCState::Committed => {},
+ InboundHTLCState::LocalRemoved(ref reason) => {
+ if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
+ } else {
+ debug_assert!(false, "Tried to fail an HTLC that was already failed");
+ }
+ return Ok(None);
+ },
+ _ => {
+ debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
+ return Err(ChannelError::Ignore(format!("Unable to find a pending HTLC which matched the given HTLC ID ({})", htlc.htlc_id)));
+ }
+ }
+ pending_idx = idx;
}
}
+ if pending_idx == core::usize::MAX {
+ #[cfg(any(test, fuzzing))]
+ // If we failed to find an HTLC to fail, make sure it was previously fulfilled and this
+ // is simply a duplicate fail, not previously failed and we failed-back too early.
+ debug_assert!(self.context.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
+ return Ok(None);
+ }
- let holder_commitment_tx = HolderCommitmentTransaction::new(
- initial_commitment_tx,
- msg.signature,
- Vec::new(),
- &self.get_holder_pubkeys().funding_pubkey,
- self.counterparty_funding_pubkey()
- );
-
- self.context.holder_signer.validate_holder_commitment(&holder_commitment_tx, Vec::new())
- .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
+ if (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 {
+ debug_assert!(force_holding_cell, "!force_holding_cell is only called when emptying the holding cell, so we shouldn't end up back in it!");
+ force_holding_cell = true;
+ }
+ // Now update local state:
+ if force_holding_cell {
+ for pending_update in self.context.holding_cell_htlc_updates.iter() {
+ match pending_update {
+ &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
+ if htlc_id_arg == htlc_id {
+ #[cfg(any(test, fuzzing))]
+ debug_assert!(self.context.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
+ return Ok(None);
+ }
+ },
+ &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
+ if htlc_id_arg == htlc_id {
+ debug_assert!(false, "Tried to fail an HTLC that was already failed");
+ return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
+ }
+ },
+ _ => {}
+ }
+ }
+ log_trace!(logger, "Placing failure for HTLC ID {} in holding cell in channel {}.", htlc_id_arg, log_bytes!(self.context.channel_id()));
+ self.context.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
+ htlc_id: htlc_id_arg,
+ err_packet,
+ });
+ return Ok(None);
+ }
- let funding_redeemscript = self.get_funding_redeemscript();
- let funding_txo = self.get_funding_txo().unwrap();
- let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
- let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
- let shutdown_script = self.context.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
- let mut monitor_signer = signer_provider.derive_channel_signer(self.context.channel_value_satoshis, self.context.channel_keys_id);
- monitor_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
- let channel_monitor = ChannelMonitor::new(self.context.secp_ctx.clone(), monitor_signer,
- shutdown_script, self.get_holder_selected_contest_delay(),
- &self.context.destination_script, (funding_txo, funding_txo_script),
- &self.context.channel_transaction_parameters,
- funding_redeemscript.clone(), self.context.channel_value_satoshis,
- obscure_factor,
- holder_commitment_tx, best_block, self.context.counterparty_node_id);
+ log_trace!(logger, "Failing HTLC ID {} back with a update_fail_htlc message in channel {}.", htlc_id_arg, log_bytes!(self.context.channel_id()));
+ {
+ let htlc = &mut self.context.pending_inbound_htlcs[pending_idx];
+ htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
+ }
- channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_bitcoin_tx.txid, Vec::new(), self.context.cur_counterparty_commitment_transaction_number, self.context.counterparty_cur_commitment_point.unwrap(), logger);
+ Ok(Some(msgs::UpdateFailHTLC {
+ channel_id: self.context.channel_id(),
+ htlc_id: htlc_id_arg,
+ reason: err_packet
+ }))
+ }
- assert_eq!(self.context.channel_state & (ChannelState::MonitorUpdateInProgress as u32), 0); // We have no had any monitor(s) yet to fail update!
- self.context.channel_state = ChannelState::FundingSent as u32;
- self.context.cur_holder_commitment_transaction_number -= 1;
- self.context.cur_counterparty_commitment_transaction_number -= 1;
+ // Message handlers:
- log_info!(logger, "Received funding_signed from peer for channel {}", log_bytes!(self.channel_id()));
+ pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, default_limits: &ChannelHandshakeLimits, their_features: &InitFeatures) -> Result<(), ChannelError> {
+ let peer_limits = if let Some(ref limits) = self.context.inbound_handshake_limits_override { limits } else { default_limits };
- let need_channel_ready = self.check_get_channel_ready(0).is_some();
- self.monitor_updating_paused(false, false, need_channel_ready, Vec::new(), Vec::new(), Vec::new());
- Ok(channel_monitor)
- }
+ // Check sanity of message fields:
+ if !self.context.is_outbound() {
+ return Err(ChannelError::Close("Got an accept_channel message from an inbound peer".to_owned()));
+ }
+ if self.context.channel_state != ChannelState::OurInitSent as u32 {
+ return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned()));
+ }
+ if msg.dust_limit_satoshis > 21000000 * 100000000 {
+ return Err(ChannelError::Close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.dust_limit_satoshis)));
+ }
+ if msg.channel_reserve_satoshis > self.context.channel_value_satoshis {
+ return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.context.channel_value_satoshis)));
+ }
+ if msg.dust_limit_satoshis > self.context.holder_selected_channel_reserve_satoshis {
+ return Err(ChannelError::Close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.dust_limit_satoshis, self.context.holder_selected_channel_reserve_satoshis)));
+ }
+ if msg.channel_reserve_satoshis > self.context.channel_value_satoshis - self.context.holder_selected_channel_reserve_satoshis {
+ return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than channel value minus our reserve ({})",
+ msg.channel_reserve_satoshis, self.context.channel_value_satoshis - self.context.holder_selected_channel_reserve_satoshis)));
+ }
+ let full_channel_value_msat = (self.context.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000;
+ if msg.htlc_minimum_msat >= full_channel_value_msat {
+ return Err(ChannelError::Close(format!("Minimum htlc value ({}) is full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
+ }
+ let max_delay_acceptable = u16::min(peer_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
+ if msg.to_self_delay > max_delay_acceptable {
+ return Err(ChannelError::Close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_delay_acceptable, msg.to_self_delay)));
+ }
+ if msg.max_accepted_htlcs < 1 {
+ return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
+ }
+ if msg.max_accepted_htlcs > MAX_HTLCS {
+ return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
+ }
- /// Handles a channel_ready message from our peer. If we've already sent our channel_ready
- /// and the channel is now usable (and public), this may generate an announcement_signatures to
- /// reply with.
- pub fn channel_ready<NS: Deref, L: Deref>(
- &mut self, msg: &msgs::ChannelReady, node_signer: &NS, genesis_block_hash: BlockHash,
- user_config: &UserConfig, best_block: &BestBlock, logger: &L
- ) -> Result<Option<msgs::AnnouncementSignatures>, ChannelError>
- where
- NS::Target: NodeSigner,
- L::Target: Logger
- {
- if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
- self.context.workaround_lnd_bug_4006 = Some(msg.clone());
- return Err(ChannelError::Ignore("Peer sent channel_ready when we needed a channel_reestablish. The peer is likely lnd, see https://github.com/lightningnetwork/lnd/issues/4006".to_owned()));
+ // Now check against optional parameters as set by config...
+ if msg.htlc_minimum_msat > peer_limits.max_htlc_minimum_msat {
+ return Err(ChannelError::Close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.htlc_minimum_msat, peer_limits.max_htlc_minimum_msat)));
+ }
+ if msg.max_htlc_value_in_flight_msat < peer_limits.min_max_htlc_value_in_flight_msat {
+ return Err(ChannelError::Close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.max_htlc_value_in_flight_msat, peer_limits.min_max_htlc_value_in_flight_msat)));
+ }
+ if msg.channel_reserve_satoshis > peer_limits.max_channel_reserve_satoshis {
+ return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, peer_limits.max_channel_reserve_satoshis)));
+ }
+ if msg.max_accepted_htlcs < peer_limits.min_max_accepted_htlcs {
+ return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, peer_limits.min_max_accepted_htlcs)));
+ }
+ if msg.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
+ return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
+ }
+ if msg.dust_limit_satoshis > MAX_CHAN_DUST_LIMIT_SATOSHIS {
+ return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
+ }
+ if msg.minimum_depth > peer_limits.max_minimum_depth {
+ return Err(ChannelError::Close(format!("We consider the minimum depth to be unreasonably large. Expected minimum: ({}). Actual: ({})", peer_limits.max_minimum_depth, msg.minimum_depth)));
}
- if let Some(scid_alias) = msg.short_channel_id_alias {
- if Some(scid_alias) != self.context.short_channel_id {
- // The scid alias provided can be used to route payments *from* our counterparty,
- // i.e. can be used for inbound payments and provided in invoices, but is not used
- // when routing outbound payments.
- self.context.latest_inbound_scid_alias = Some(scid_alias);
+ if let Some(ty) = &msg.channel_type {
+ if *ty != self.context.channel_type {
+ return Err(ChannelError::Close("Channel Type in accept_channel didn't match the one sent in open_channel.".to_owned()));
+ }
+ } else if their_features.supports_channel_type() {
+ // Assume they've accepted the channel type as they said they understand it.
+ } else {
+ let channel_type = ChannelTypeFeatures::from_init(&their_features);
+ if channel_type != ChannelTypeFeatures::only_static_remote_key() {
+ return Err(ChannelError::Close("Only static_remote_key is supported for non-negotiated channel types".to_owned()));
}
+ self.context.channel_type = channel_type;
}
- let non_shutdown_state = self.context.channel_state & (!MULTI_STATE_FLAGS);
-
- if non_shutdown_state == ChannelState::FundingSent as u32 {
- self.context.channel_state |= ChannelState::TheirChannelReady as u32;
- } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurChannelReady as u32) {
- self.context.channel_state = ChannelState::ChannelReady as u32 | (self.context.channel_state & MULTI_STATE_FLAGS);
- self.context.update_time_counter += 1;
- } else if self.context.channel_state & (ChannelState::ChannelReady as u32) != 0 ||
- // If we reconnected before sending our `channel_ready` they may still resend theirs:
- (self.context.channel_state & (ChannelState::FundingSent as u32 | ChannelState::TheirChannelReady as u32) ==
- (ChannelState::FundingSent as u32 | ChannelState::TheirChannelReady as u32))
- {
- // They probably disconnected/reconnected and re-sent the channel_ready, which is
- // required, or they're sending a fresh SCID alias.
- let expected_point =
- if self.context.cur_counterparty_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 {
- // If they haven't ever sent an updated point, the point they send should match
- // the current one.
- self.context.counterparty_cur_commitment_point
- } else if self.context.cur_counterparty_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 2 {
- // If we've advanced the commitment number once, the second commitment point is
- // at `counterparty_prev_commitment_point`, which is not yet revoked.
- debug_assert!(self.context.counterparty_prev_commitment_point.is_some());
- self.context.counterparty_prev_commitment_point
- } else {
- // If they have sent updated points, channel_ready is always supposed to match
- // their "first" point, which we re-derive here.
- Some(PublicKey::from_secret_key(&self.context.secp_ctx, &SecretKey::from_slice(
- &self.context.commitment_secrets.get_secret(INITIAL_COMMITMENT_NUMBER - 1).expect("We should have all prev secrets available")
- ).expect("We already advanced, so previous secret keys should have been validated already")))
- };
- if expected_point != Some(msg.next_per_commitment_point) {
- return Err(ChannelError::Close("Peer sent a reconnect channel_ready with a different point".to_owned()));
+ let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
+ match &msg.shutdown_scriptpubkey {
+ &Some(ref script) => {
+ // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
+ if script.len() == 0 {
+ None
+ } else {
+ if !script::is_bolt2_compliant(&script, their_features) {
+ return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)));
+ }
+ Some(script.clone())
+ }
+ },
+ // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel
+ &None => {
+ return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out".to_owned()));
+ }
}
- return Ok(None);
- } else {
- return Err(ChannelError::Close("Peer sent a channel_ready at a strange time".to_owned()));
- }
-
- self.context.counterparty_prev_commitment_point = self.context.counterparty_cur_commitment_point;
- self.context.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
-
- log_info!(logger, "Received channel_ready from peer for channel {}", log_bytes!(self.channel_id()));
+ } else { None };
- Ok(self.get_announcement_sigs(node_signer, genesis_block_hash, user_config, best_block.height(), logger))
- }
+ self.context.counterparty_dust_limit_satoshis = msg.dust_limit_satoshis;
+ self.context.counterparty_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.context.channel_value_satoshis * 1000);
+ self.context.counterparty_selected_channel_reserve_satoshis = Some(msg.channel_reserve_satoshis);
+ self.context.counterparty_htlc_minimum_msat = msg.htlc_minimum_msat;
+ self.context.counterparty_max_accepted_htlcs = msg.max_accepted_htlcs;
- /// Returns transaction if there is pending funding transaction that is yet to broadcast
- pub fn unbroadcasted_funding(&self) -> Option<Transaction> {
- if self.context.channel_state & (ChannelState::FundingCreated as u32) != 0 {
- self.context.funding_transaction.clone()
+ if peer_limits.trust_own_funding_0conf {
+ self.context.minimum_depth = Some(msg.minimum_depth);
} else {
- None
+ self.context.minimum_depth = Some(cmp::max(1, msg.minimum_depth));
}
- }
- /// Returns a HTLCStats about inbound pending htlcs
- fn get_inbound_pending_htlc_stats(&self, outbound_feerate_update: Option<u32>) -> HTLCStats {
- let mut stats = HTLCStats {
- pending_htlcs: self.context.pending_inbound_htlcs.len() as u32,
- pending_htlcs_value_msat: 0,
- on_counterparty_tx_dust_exposure_msat: 0,
- on_holder_tx_dust_exposure_msat: 0,
- holding_cell_msat: 0,
- on_holder_tx_holding_cell_htlcs_count: 0,
+ let counterparty_pubkeys = ChannelPublicKeys {
+ funding_pubkey: msg.funding_pubkey,
+ revocation_basepoint: msg.revocation_basepoint,
+ payment_point: msg.payment_point,
+ delayed_payment_basepoint: msg.delayed_payment_basepoint,
+ htlc_basepoint: msg.htlc_basepoint
};
- let (htlc_timeout_dust_limit, htlc_success_dust_limit) = if self.context.opt_anchors() {
- (0, 0)
- } else {
- let dust_buffer_feerate = self.get_dust_buffer_feerate(outbound_feerate_update) as u64;
- (dust_buffer_feerate * htlc_timeout_tx_weight(false) / 1000,
- dust_buffer_feerate * htlc_success_tx_weight(false) / 1000)
- };
- let counterparty_dust_limit_timeout_sat = htlc_timeout_dust_limit + self.context.counterparty_dust_limit_satoshis;
- let holder_dust_limit_success_sat = htlc_success_dust_limit + self.context.holder_dust_limit_satoshis;
- for ref htlc in self.context.pending_inbound_htlcs.iter() {
- stats.pending_htlcs_value_msat += htlc.amount_msat;
- if htlc.amount_msat / 1000 < counterparty_dust_limit_timeout_sat {
- stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
- }
- if htlc.amount_msat / 1000 < holder_dust_limit_success_sat {
- stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
- }
- }
- stats
- }
+ self.context.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
+ selected_contest_delay: msg.to_self_delay,
+ pubkeys: counterparty_pubkeys,
+ });
- /// Returns a HTLCStats about pending outbound htlcs, *including* pending adds in our holding cell.
- fn get_outbound_pending_htlc_stats(&self, outbound_feerate_update: Option<u32>) -> HTLCStats {
- let mut stats = HTLCStats {
- pending_htlcs: self.context.pending_outbound_htlcs.len() as u32,
- pending_htlcs_value_msat: 0,
- on_counterparty_tx_dust_exposure_msat: 0,
- on_holder_tx_dust_exposure_msat: 0,
- holding_cell_msat: 0,
- on_holder_tx_holding_cell_htlcs_count: 0,
- };
+ self.context.counterparty_cur_commitment_point = Some(msg.first_per_commitment_point);
+ self.context.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
- let (htlc_timeout_dust_limit, htlc_success_dust_limit) = if self.context.opt_anchors() {
- (0, 0)
- } else {
- let dust_buffer_feerate = self.get_dust_buffer_feerate(outbound_feerate_update) as u64;
- (dust_buffer_feerate * htlc_timeout_tx_weight(false) / 1000,
- dust_buffer_feerate * htlc_success_tx_weight(false) / 1000)
- };
- let counterparty_dust_limit_success_sat = htlc_success_dust_limit + self.context.counterparty_dust_limit_satoshis;
- let holder_dust_limit_timeout_sat = htlc_timeout_dust_limit + self.context.holder_dust_limit_satoshis;
- for ref htlc in self.context.pending_outbound_htlcs.iter() {
- stats.pending_htlcs_value_msat += htlc.amount_msat;
- if htlc.amount_msat / 1000 < counterparty_dust_limit_success_sat {
- stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
- }
- if htlc.amount_msat / 1000 < holder_dust_limit_timeout_sat {
- stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
- }
- }
+ self.context.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
+ self.context.inbound_handshake_limits_override = None; // We're done enforcing limits on our peer's handshake now.
- for update in self.context.holding_cell_htlc_updates.iter() {
- if let &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, .. } = update {
- stats.pending_htlcs += 1;
- stats.pending_htlcs_value_msat += amount_msat;
- stats.holding_cell_msat += amount_msat;
- if *amount_msat / 1000 < counterparty_dust_limit_success_sat {
- stats.on_counterparty_tx_dust_exposure_msat += amount_msat;
- }
- if *amount_msat / 1000 < holder_dust_limit_timeout_sat {
- stats.on_holder_tx_dust_exposure_msat += amount_msat;
- } else {
- stats.on_holder_tx_holding_cell_htlcs_count += 1;
- }
- }
- }
- stats
+ Ok(())
}
- /// Get the available balances, see [`AvailableBalances`]'s fields for more info.
- /// Doesn't bother handling the
- /// if-we-removed-it-already-but-haven't-fully-resolved-they-can-still-send-an-inbound-HTLC
- /// corner case properly.
- pub fn get_available_balances(&self) -> AvailableBalances {
- // Note that we have to handle overflow due to the above case.
- let inbound_stats = self.get_inbound_pending_htlc_stats(None);
- let outbound_stats = self.get_outbound_pending_htlc_stats(None);
+ fn funding_created_signature<L: Deref>(&mut self, sig: &Signature, logger: &L) -> Result<(Txid, CommitmentTransaction, Signature), ChannelError> where L::Target: Logger {
+ let funding_script = self.context.get_funding_redeemscript();
- let mut balance_msat = self.context.value_to_self_msat;
- for ref htlc in self.context.pending_inbound_htlcs.iter() {
- if let InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(_)) = htlc.state {
- balance_msat += htlc.amount_msat;
- }
+ let keys = self.context.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
+ let initial_commitment_tx = self.context.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &keys, true, false, logger).tx;
+ {
+ let trusted_tx = initial_commitment_tx.trust();
+ let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
+ let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.context.channel_value_satoshis);
+ // They sign the holder commitment transaction...
+ log_trace!(logger, "Checking funding_created tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} for channel {}.",
+ log_bytes!(sig.serialize_compact()[..]), log_bytes!(self.context.counterparty_funding_pubkey().serialize()),
+ encode::serialize_hex(&initial_commitment_bitcoin_tx.transaction), log_bytes!(sighash[..]),
+ encode::serialize_hex(&funding_script), log_bytes!(self.context.channel_id()));
+ secp_check!(self.context.secp_ctx.verify_ecdsa(&sighash, &sig, self.context.counterparty_funding_pubkey()), "Invalid funding_created signature from peer".to_owned());
}
- balance_msat -= outbound_stats.pending_htlcs_value_msat;
- let outbound_capacity_msat = self.context.value_to_self_msat
- .saturating_sub(outbound_stats.pending_htlcs_value_msat)
- .saturating_sub(
- self.context.counterparty_selected_channel_reserve_satoshis.unwrap_or(0) * 1000);
-
- let mut available_capacity_msat = outbound_capacity_msat;
+ let counterparty_keys = self.context.build_remote_transaction_keys();
+ let counterparty_initial_commitment_tx = self.context.build_commitment_transaction(self.context.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).tx;
- if self.is_outbound() {
- // We should mind channel commit tx fee when computing how much of the available capacity
- // can be used in the next htlc. Mirrors the logic in send_htlc.
- //
- // The fee depends on whether the amount we will be sending is above dust or not,
- // and the answer will in turn change the amount itself — making it a circular
- // dependency.
- // This complicates the computation around dust-values, up to the one-htlc-value.
- let mut real_dust_limit_timeout_sat = self.context.holder_dust_limit_satoshis;
- if !self.context.opt_anchors() {
- real_dust_limit_timeout_sat += self.context.feerate_per_kw as u64 * htlc_timeout_tx_weight(false) / 1000;
- }
+ let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
+ let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
+ log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
+ log_bytes!(self.context.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
- let htlc_above_dust = HTLCCandidate::new(real_dust_limit_timeout_sat * 1000, HTLCInitiator::LocalOffered);
- let max_reserved_commit_tx_fee_msat = FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * self.next_local_commit_tx_fee_msat(htlc_above_dust, Some(()));
- let htlc_dust = HTLCCandidate::new(real_dust_limit_timeout_sat * 1000 - 1, HTLCInitiator::LocalOffered);
- let min_reserved_commit_tx_fee_msat = FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * self.next_local_commit_tx_fee_msat(htlc_dust, Some(()));
+ let counterparty_signature = self.context.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, Vec::new(), &self.context.secp_ctx)
+ .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0;
- // We will first subtract the fee as if we were above-dust. Then, if the resulting
- // value ends up being below dust, we have this fee available again. In that case,
- // match the value to right-below-dust.
- let mut capacity_minus_commitment_fee_msat: i64 = (available_capacity_msat as i64) - (max_reserved_commit_tx_fee_msat as i64);
- if capacity_minus_commitment_fee_msat < (real_dust_limit_timeout_sat as i64) * 1000 {
- let one_htlc_difference_msat = max_reserved_commit_tx_fee_msat - min_reserved_commit_tx_fee_msat;
- debug_assert!(one_htlc_difference_msat != 0);
- capacity_minus_commitment_fee_msat += one_htlc_difference_msat as i64;
- capacity_minus_commitment_fee_msat = cmp::min(real_dust_limit_timeout_sat as i64 * 1000 - 1, capacity_minus_commitment_fee_msat);
- available_capacity_msat = cmp::max(0, cmp::min(capacity_minus_commitment_fee_msat, available_capacity_msat as i64)) as u64;
- } else {
- available_capacity_msat = capacity_minus_commitment_fee_msat as u64;
- }
- } else {
- // If the channel is inbound (i.e. counterparty pays the fee), we need to make sure
- // sending a new HTLC won't reduce their balance below our reserve threshold.
- let mut real_dust_limit_success_sat = self.context.counterparty_dust_limit_satoshis;
- if !self.context.opt_anchors() {
- real_dust_limit_success_sat += self.context.feerate_per_kw as u64 * htlc_success_tx_weight(false) / 1000;
- }
+ // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
+ Ok((counterparty_initial_bitcoin_tx.txid, initial_commitment_tx, counterparty_signature))
+ }
- let htlc_above_dust = HTLCCandidate::new(real_dust_limit_success_sat * 1000, HTLCInitiator::LocalOffered);
- let max_reserved_commit_tx_fee_msat = self.next_remote_commit_tx_fee_msat(htlc_above_dust, None);
+ pub fn funding_created<SP: Deref, L: Deref>(
+ &mut self, msg: &msgs::FundingCreated, best_block: BestBlock, signer_provider: &SP, logger: &L
+ ) -> Result<(msgs::FundingSigned, ChannelMonitor<Signer>), ChannelError>
+ where
+ SP::Target: SignerProvider<Signer = Signer>,
+ L::Target: Logger
+ {
+ if self.context.is_outbound() {
+ return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned()));
+ }
+ if self.context.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
+ // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
+ // remember the channel, so it's safe to just send an error_message here and drop the
+ // channel.
+ return Err(ChannelError::Close("Received funding_created after we got the channel!".to_owned()));
+ }
+ if self.context.inbound_awaiting_accept {
+ return Err(ChannelError::Close("FundingCreated message received before the channel was accepted".to_owned()));
+ }
+ if self.context.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
+ self.context.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
+ self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
+ panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
+ }
- let holder_selected_chan_reserve_msat = self.context.holder_selected_channel_reserve_satoshis * 1000;
- let remote_balance_msat = (self.context.channel_value_satoshis * 1000 - self.context.value_to_self_msat)
- .saturating_sub(inbound_stats.pending_htlcs_value_msat);
+ let funding_txo = OutPoint { txid: msg.funding_txid, index: msg.funding_output_index };
+ self.context.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
+ // This is an externally observable change before we finish all our checks. In particular
+ // funding_created_signature may fail.
+ self.context.holder_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
- if remote_balance_msat < max_reserved_commit_tx_fee_msat + holder_selected_chan_reserve_msat {
- // If another HTLC's fee would reduce the remote's balance below the reserve limit
- // we've selected for them, we can only send dust HTLCs.
- available_capacity_msat = cmp::min(available_capacity_msat, real_dust_limit_success_sat * 1000 - 1);
+ let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
+ Ok(res) => res,
+ Err(ChannelError::Close(e)) => {
+ self.context.channel_transaction_parameters.funding_outpoint = None;
+ return Err(ChannelError::Close(e));
+ },
+ Err(e) => {
+ // The only error we know how to handle is ChannelError::Close, so we fall over here
+ // to make sure we don't continue with an inconsistent state.
+ panic!("unexpected error type from funding_created_signature {:?}", e);
}
- }
+ };
- let mut next_outbound_htlc_minimum_msat = self.context.counterparty_htlc_minimum_msat;
+ let holder_commitment_tx = HolderCommitmentTransaction::new(
+ initial_commitment_tx,
+ msg.signature,
+ Vec::new(),
+ &self.context.get_holder_pubkeys().funding_pubkey,
+ self.context.counterparty_funding_pubkey()
+ );
- // If we get close to our maximum dust exposure, we end up in a situation where we can send
- // between zero and the remaining dust exposure limit remaining OR above the dust limit.
- // Because we cannot express this as a simple min/max, we prefer to tell the user they can
- // send above the dust limit (as the router can always overpay to meet the dust limit).
- let mut remaining_msat_below_dust_exposure_limit = None;
- let mut dust_exposure_dust_limit_msat = 0;
+ self.context.holder_signer.validate_holder_commitment(&holder_commitment_tx, Vec::new())
+ .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
- let (htlc_success_dust_limit, htlc_timeout_dust_limit) = if self.context.opt_anchors() {
- (self.context.counterparty_dust_limit_satoshis, self.context.holder_dust_limit_satoshis)
- } else {
- let dust_buffer_feerate = self.get_dust_buffer_feerate(None) as u64;
- (self.context.counterparty_dust_limit_satoshis + dust_buffer_feerate * htlc_success_tx_weight(false) / 1000,
- self.context.holder_dust_limit_satoshis + dust_buffer_feerate * htlc_timeout_tx_weight(false) / 1000)
- };
- let on_counterparty_dust_htlc_exposure_msat = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat;
- if on_counterparty_dust_htlc_exposure_msat as i64 + htlc_success_dust_limit as i64 * 1000 - 1 > self.get_max_dust_htlc_exposure_msat() as i64 {
- remaining_msat_below_dust_exposure_limit =
- Some(self.get_max_dust_htlc_exposure_msat().saturating_sub(on_counterparty_dust_htlc_exposure_msat));
- dust_exposure_dust_limit_msat = cmp::max(dust_exposure_dust_limit_msat, htlc_success_dust_limit * 1000);
- }
+ // Now that we're past error-generating stuff, update our local state:
- let on_holder_dust_htlc_exposure_msat = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
- if on_holder_dust_htlc_exposure_msat as i64 + htlc_timeout_dust_limit as i64 * 1000 - 1 > self.get_max_dust_htlc_exposure_msat() as i64 {
- remaining_msat_below_dust_exposure_limit = Some(cmp::min(
- remaining_msat_below_dust_exposure_limit.unwrap_or(u64::max_value()),
- self.get_max_dust_htlc_exposure_msat().saturating_sub(on_holder_dust_htlc_exposure_msat)));
- dust_exposure_dust_limit_msat = cmp::max(dust_exposure_dust_limit_msat, htlc_timeout_dust_limit * 1000);
- }
+ let funding_redeemscript = self.context.get_funding_redeemscript();
+ let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
+ let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.context.get_holder_pubkeys().payment_point, &self.context.get_counterparty_pubkeys().payment_point, self.context.is_outbound());
+ let shutdown_script = self.context.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
+ let mut monitor_signer = signer_provider.derive_channel_signer(self.context.channel_value_satoshis, self.context.channel_keys_id);
+ monitor_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
+ let channel_monitor = ChannelMonitor::new(self.context.secp_ctx.clone(), monitor_signer,
+ shutdown_script, self.context.get_holder_selected_contest_delay(),
+ &self.context.destination_script, (funding_txo, funding_txo_script.clone()),
+ &self.context.channel_transaction_parameters,
+ funding_redeemscript.clone(), self.context.channel_value_satoshis,
+ obscure_factor,
+ holder_commitment_tx, best_block, self.context.counterparty_node_id);
- if let Some(remaining_limit_msat) = remaining_msat_below_dust_exposure_limit {
- if available_capacity_msat < dust_exposure_dust_limit_msat {
- available_capacity_msat = cmp::min(available_capacity_msat, remaining_limit_msat);
- } else {
- next_outbound_htlc_minimum_msat = cmp::max(next_outbound_htlc_minimum_msat, dust_exposure_dust_limit_msat);
- }
- }
+ channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_commitment_txid, Vec::new(), self.context.cur_counterparty_commitment_transaction_number, self.context.counterparty_cur_commitment_point.unwrap(), logger);
- available_capacity_msat = cmp::min(available_capacity_msat,
- self.context.counterparty_max_htlc_value_in_flight_msat - outbound_stats.pending_htlcs_value_msat);
+ self.context.channel_state = ChannelState::FundingSent as u32;
+ self.context.channel_id = funding_txo.to_channel_id();
+ self.context.cur_counterparty_commitment_transaction_number -= 1;
+ self.context.cur_holder_commitment_transaction_number -= 1;
- if outbound_stats.pending_htlcs + 1 > self.context.counterparty_max_accepted_htlcs as u32 {
- available_capacity_msat = 0;
- }
+ log_info!(logger, "Generated funding_signed for peer for channel {}", log_bytes!(self.context.channel_id()));
- AvailableBalances {
- inbound_capacity_msat: cmp::max(self.context.channel_value_satoshis as i64 * 1000
- - self.context.value_to_self_msat as i64
- - self.get_inbound_pending_htlc_stats(None).pending_htlcs_value_msat as i64
- - self.context.holder_selected_channel_reserve_satoshis as i64 * 1000,
- 0) as u64,
- outbound_capacity_msat,
- next_outbound_htlc_limit_msat: available_capacity_msat,
- next_outbound_htlc_minimum_msat,
- balance_msat,
- }
- }
+ let need_channel_ready = self.check_get_channel_ready(0).is_some();
+ self.monitor_updating_paused(false, false, need_channel_ready, Vec::new(), Vec::new(), Vec::new());
- pub fn get_holder_counterparty_selected_channel_reserve_satoshis(&self) -> (u64, Option<u64>) {
- (self.context.holder_selected_channel_reserve_satoshis, self.context.counterparty_selected_channel_reserve_satoshis)
+ Ok((msgs::FundingSigned {
+ channel_id: self.context.channel_id,
+ signature,
+ #[cfg(taproot)]
+ partial_signature_with_nonce: None,
+ }, channel_monitor))
}
- // Get the fee cost in MSATS of a commitment tx with a given number of HTLC outputs.
- // Note that num_htlcs should not include dust HTLCs.
- fn commit_tx_fee_msat(feerate_per_kw: u32, num_htlcs: usize, opt_anchors: bool) -> u64 {
- // Note that we need to divide before multiplying to round properly,
- // since the lowest denomination of bitcoin on-chain is the satoshi.
- (commitment_tx_base_weight(opt_anchors) + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) * feerate_per_kw as u64 / 1000 * 1000
- }
+ /// Handles a funding_signed message from the remote end.
+ /// If this call is successful, broadcast the funding transaction (and not before!)
+ pub fn funding_signed<SP: Deref, L: Deref>(
+ &mut self, msg: &msgs::FundingSigned, best_block: BestBlock, signer_provider: &SP, logger: &L
+ ) -> Result<ChannelMonitor<Signer>, ChannelError>
+ where
+ SP::Target: SignerProvider<Signer = Signer>,
+ L::Target: Logger
+ {
+ if !self.context.is_outbound() {
+ return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
+ }
+ if self.context.channel_state & !(ChannelState::MonitorUpdateInProgress as u32) != ChannelState::FundingCreated as u32 {
+ return Err(ChannelError::Close("Received funding_signed in strange state!".to_owned()));
+ }
+ if self.context.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
+ self.context.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
+ self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
+ panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
+ }
- // Get the fee cost in SATS of a commitment tx with a given number of HTLC outputs.
- // Note that num_htlcs should not include dust HTLCs.
- #[inline]
- fn commit_tx_fee_sat(feerate_per_kw: u32, num_htlcs: usize, opt_anchors: bool) -> u64 {
- feerate_per_kw as u64 * (commitment_tx_base_weight(opt_anchors) + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000
- }
+ let funding_script = self.context.get_funding_redeemscript();
- /// Get the commitment tx fee for the local's (i.e. our) next commitment transaction based on the
- /// number of pending HTLCs that are on track to be in our next commitment tx.
- ///
- /// Optionally includes the `HTLCCandidate` given by `htlc` and an additional non-dust HTLC if
- /// `fee_spike_buffer_htlc` is `Some`.
- ///
- /// The first extra HTLC is useful for determining whether we can accept a further HTLC, the
- /// second allows for creating a buffer to ensure a further HTLC can always be accepted/added.
- ///
- /// Dust HTLCs are excluded.
- fn next_local_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
- assert!(self.is_outbound());
+ let counterparty_keys = self.context.build_remote_transaction_keys();
+ let counterparty_initial_commitment_tx = self.context.build_commitment_transaction(self.context.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).tx;
+ let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
+ let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
- let (htlc_success_dust_limit, htlc_timeout_dust_limit) = if self.context.opt_anchors() {
- (0, 0)
- } else {
- (self.context.feerate_per_kw as u64 * htlc_success_tx_weight(false) / 1000,
- self.context.feerate_per_kw as u64 * htlc_timeout_tx_weight(false) / 1000)
- };
- let real_dust_limit_success_sat = htlc_success_dust_limit + self.context.holder_dust_limit_satoshis;
- let real_dust_limit_timeout_sat = htlc_timeout_dust_limit + self.context.holder_dust_limit_satoshis;
+ log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
+ log_bytes!(self.context.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
- let mut addl_htlcs = 0;
- if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
- match htlc.origin {
- HTLCInitiator::LocalOffered => {
- if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
- addl_htlcs += 1;
- }
- },
- HTLCInitiator::RemoteOffered => {
- if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
- addl_htlcs += 1;
- }
+ let holder_signer = self.context.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
+ let initial_commitment_tx = self.context.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &holder_signer, true, false, logger).tx;
+ {
+ let trusted_tx = initial_commitment_tx.trust();
+ let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
+ let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.context.channel_value_satoshis);
+ // They sign our commitment transaction, allowing us to broadcast the tx if we wish.
+ if let Err(_) = self.context.secp_ctx.verify_ecdsa(&sighash, &msg.signature, &self.context.get_counterparty_pubkeys().funding_pubkey) {
+ return Err(ChannelError::Close("Invalid funding_signed signature from peer".to_owned()));
}
}
- let mut included_htlcs = 0;
- for ref htlc in self.context.pending_inbound_htlcs.iter() {
- if htlc.amount_msat / 1000 < real_dust_limit_success_sat {
- continue
- }
- // We include LocalRemoved HTLCs here because we may still need to broadcast a commitment
- // transaction including this HTLC if it times out before they RAA.
- included_htlcs += 1;
- }
+ let holder_commitment_tx = HolderCommitmentTransaction::new(
+ initial_commitment_tx,
+ msg.signature,
+ Vec::new(),
+ &self.context.get_holder_pubkeys().funding_pubkey,
+ self.context.counterparty_funding_pubkey()
+ );
- for ref htlc in self.context.pending_outbound_htlcs.iter() {
- if htlc.amount_msat / 1000 < real_dust_limit_timeout_sat {
- continue
- }
- match htlc.state {
- OutboundHTLCState::LocalAnnounced {..} => included_htlcs += 1,
- OutboundHTLCState::Committed => included_htlcs += 1,
- OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
- // We don't include AwaitingRemoteRevokeToRemove HTLCs because our next commitment
- // transaction won't be generated until they send us their next RAA, which will mean
- // dropping any HTLCs in this state.
- _ => {},
- }
- }
+ self.context.holder_signer.validate_holder_commitment(&holder_commitment_tx, Vec::new())
+ .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
- for htlc in self.context.holding_cell_htlc_updates.iter() {
- match htlc {
- &HTLCUpdateAwaitingACK::AddHTLC { amount_msat, .. } => {
- if amount_msat / 1000 < real_dust_limit_timeout_sat {
- continue
- }
- included_htlcs += 1
- },
- _ => {}, // Don't include claims/fails that are awaiting ack, because once we get the
- // ack we're guaranteed to never include them in commitment txs anymore.
- }
- }
- let num_htlcs = included_htlcs + addl_htlcs;
- let res = Self::commit_tx_fee_msat(self.context.feerate_per_kw, num_htlcs, self.context.opt_anchors());
- #[cfg(any(test, fuzzing))]
- {
- let mut fee = res;
- if fee_spike_buffer_htlc.is_some() {
- fee = Self::commit_tx_fee_msat(self.context.feerate_per_kw, num_htlcs - 1, self.context.opt_anchors());
- }
- let total_pending_htlcs = self.context.pending_inbound_htlcs.len() + self.context.pending_outbound_htlcs.len()
- + self.context.holding_cell_htlc_updates.len();
- let commitment_tx_info = CommitmentTxInfoCached {
- fee,
- total_pending_htlcs,
- next_holder_htlc_id: match htlc.origin {
- HTLCInitiator::LocalOffered => self.context.next_holder_htlc_id + 1,
- HTLCInitiator::RemoteOffered => self.context.next_holder_htlc_id,
- },
- next_counterparty_htlc_id: match htlc.origin {
- HTLCInitiator::LocalOffered => self.context.next_counterparty_htlc_id,
- HTLCInitiator::RemoteOffered => self.context.next_counterparty_htlc_id + 1,
- },
- feerate: self.context.feerate_per_kw,
- };
- *self.context.next_local_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
- }
- res
- }
+ let funding_redeemscript = self.context.get_funding_redeemscript();
+ let funding_txo = self.context.get_funding_txo().unwrap();
+ let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
+ let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.context.get_holder_pubkeys().payment_point, &self.context.get_counterparty_pubkeys().payment_point, self.context.is_outbound());
+ let shutdown_script = self.context.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
+ let mut monitor_signer = signer_provider.derive_channel_signer(self.context.channel_value_satoshis, self.context.channel_keys_id);
+ monitor_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
+ let channel_monitor = ChannelMonitor::new(self.context.secp_ctx.clone(), monitor_signer,
+ shutdown_script, self.context.get_holder_selected_contest_delay(),
+ &self.context.destination_script, (funding_txo, funding_txo_script),
+ &self.context.channel_transaction_parameters,
+ funding_redeemscript.clone(), self.context.channel_value_satoshis,
+ obscure_factor,
+ holder_commitment_tx, best_block, self.context.counterparty_node_id);
- /// Get the commitment tx fee for the remote's next commitment transaction based on the number of
- /// pending HTLCs that are on track to be in their next commitment tx
- ///
- /// Optionally includes the `HTLCCandidate` given by `htlc` and an additional non-dust HTLC if
- /// `fee_spike_buffer_htlc` is `Some`.
- ///
- /// The first extra HTLC is useful for determining whether we can accept a further HTLC, the
- /// second allows for creating a buffer to ensure a further HTLC can always be accepted/added.
- ///
- /// Dust HTLCs are excluded.
- fn next_remote_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
- assert!(!self.is_outbound());
+ channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_bitcoin_tx.txid, Vec::new(), self.context.cur_counterparty_commitment_transaction_number, self.context.counterparty_cur_commitment_point.unwrap(), logger);
- let (htlc_success_dust_limit, htlc_timeout_dust_limit) = if self.context.opt_anchors() {
- (0, 0)
- } else {
- (self.context.feerate_per_kw as u64 * htlc_success_tx_weight(false) / 1000,
- self.context.feerate_per_kw as u64 * htlc_timeout_tx_weight(false) / 1000)
- };
- let real_dust_limit_success_sat = htlc_success_dust_limit + self.context.counterparty_dust_limit_satoshis;
- let real_dust_limit_timeout_sat = htlc_timeout_dust_limit + self.context.counterparty_dust_limit_satoshis;
+ assert_eq!(self.context.channel_state & (ChannelState::MonitorUpdateInProgress as u32), 0); // We have no had any monitor(s) yet to fail update!
+ self.context.channel_state = ChannelState::FundingSent as u32;
+ self.context.cur_holder_commitment_transaction_number -= 1;
+ self.context.cur_counterparty_commitment_transaction_number -= 1;
- let mut addl_htlcs = 0;
- if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
- match htlc.origin {
- HTLCInitiator::LocalOffered => {
- if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
- addl_htlcs += 1;
- }
- },
- HTLCInitiator::RemoteOffered => {
- if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
- addl_htlcs += 1;
- }
- }
+ log_info!(logger, "Received funding_signed from peer for channel {}", log_bytes!(self.context.channel_id()));
+
+ let need_channel_ready = self.check_get_channel_ready(0).is_some();
+ self.monitor_updating_paused(false, false, need_channel_ready, Vec::new(), Vec::new(), Vec::new());
+ Ok(channel_monitor)
+ }
+
+ /// Handles a channel_ready message from our peer. If we've already sent our channel_ready
+ /// and the channel is now usable (and public), this may generate an announcement_signatures to
+ /// reply with.
+ pub fn channel_ready<NS: Deref, L: Deref>(
+ &mut self, msg: &msgs::ChannelReady, node_signer: &NS, genesis_block_hash: BlockHash,
+ user_config: &UserConfig, best_block: &BestBlock, logger: &L
+ ) -> Result<Option<msgs::AnnouncementSignatures>, ChannelError>
+ where
+ NS::Target: NodeSigner,
+ L::Target: Logger
+ {
+ if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
+ self.context.workaround_lnd_bug_4006 = Some(msg.clone());
+ return Err(ChannelError::Ignore("Peer sent channel_ready when we needed a channel_reestablish. The peer is likely lnd, see https://github.com/lightningnetwork/lnd/issues/4006".to_owned()));
}
- // When calculating the set of HTLCs which will be included in their next commitment_signed, all
- // non-dust inbound HTLCs are included (as all states imply it will be included) and only
- // committed outbound HTLCs, see below.
- let mut included_htlcs = 0;
- for ref htlc in self.context.pending_inbound_htlcs.iter() {
- if htlc.amount_msat / 1000 <= real_dust_limit_timeout_sat {
- continue
+ if let Some(scid_alias) = msg.short_channel_id_alias {
+ if Some(scid_alias) != self.context.short_channel_id {
+ // The scid alias provided can be used to route payments *from* our counterparty,
+ // i.e. can be used for inbound payments and provided in invoices, but is not used
+ // when routing outbound payments.
+ self.context.latest_inbound_scid_alias = Some(scid_alias);
}
- included_htlcs += 1;
}
- for ref htlc in self.context.pending_outbound_htlcs.iter() {
- if htlc.amount_msat / 1000 <= real_dust_limit_success_sat {
- continue
- }
- // We only include outbound HTLCs if it will not be included in their next commitment_signed,
- // i.e. if they've responded to us with an RAA after announcement.
- match htlc.state {
- OutboundHTLCState::Committed => included_htlcs += 1,
- OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
- OutboundHTLCState::LocalAnnounced { .. } => included_htlcs += 1,
- _ => {},
+ let non_shutdown_state = self.context.channel_state & (!MULTI_STATE_FLAGS);
+
+ if non_shutdown_state == ChannelState::FundingSent as u32 {
+ self.context.channel_state |= ChannelState::TheirChannelReady as u32;
+ } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurChannelReady as u32) {
+ self.context.channel_state = ChannelState::ChannelReady as u32 | (self.context.channel_state & MULTI_STATE_FLAGS);
+ self.context.update_time_counter += 1;
+ } else if self.context.channel_state & (ChannelState::ChannelReady as u32) != 0 ||
+ // If we reconnected before sending our `channel_ready` they may still resend theirs:
+ (self.context.channel_state & (ChannelState::FundingSent as u32 | ChannelState::TheirChannelReady as u32) ==
+ (ChannelState::FundingSent as u32 | ChannelState::TheirChannelReady as u32))
+ {
+ // They probably disconnected/reconnected and re-sent the channel_ready, which is
+ // required, or they're sending a fresh SCID alias.
+ let expected_point =
+ if self.context.cur_counterparty_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 {
+ // If they haven't ever sent an updated point, the point they send should match
+ // the current one.
+ self.context.counterparty_cur_commitment_point
+ } else if self.context.cur_counterparty_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 2 {
+ // If we've advanced the commitment number once, the second commitment point is
+ // at `counterparty_prev_commitment_point`, which is not yet revoked.
+ debug_assert!(self.context.counterparty_prev_commitment_point.is_some());
+ self.context.counterparty_prev_commitment_point
+ } else {
+ // If they have sent updated points, channel_ready is always supposed to match
+ // their "first" point, which we re-derive here.
+ Some(PublicKey::from_secret_key(&self.context.secp_ctx, &SecretKey::from_slice(
+ &self.context.commitment_secrets.get_secret(INITIAL_COMMITMENT_NUMBER - 1).expect("We should have all prev secrets available")
+ ).expect("We already advanced, so previous secret keys should have been validated already")))
+ };
+ if expected_point != Some(msg.next_per_commitment_point) {
+ return Err(ChannelError::Close("Peer sent a reconnect channel_ready with a different point".to_owned()));
}
+ return Ok(None);
+ } else {
+ return Err(ChannelError::Close("Peer sent a channel_ready at a strange time".to_owned()));
}
- let num_htlcs = included_htlcs + addl_htlcs;
- let res = Self::commit_tx_fee_msat(self.context.feerate_per_kw, num_htlcs, self.context.opt_anchors());
- #[cfg(any(test, fuzzing))]
- {
- let mut fee = res;
- if fee_spike_buffer_htlc.is_some() {
- fee = Self::commit_tx_fee_msat(self.context.feerate_per_kw, num_htlcs - 1, self.context.opt_anchors());
- }
- let total_pending_htlcs = self.context.pending_inbound_htlcs.len() + self.context.pending_outbound_htlcs.len();
- let commitment_tx_info = CommitmentTxInfoCached {
- fee,
- total_pending_htlcs,
- next_holder_htlc_id: match htlc.origin {
- HTLCInitiator::LocalOffered => self.context.next_holder_htlc_id + 1,
- HTLCInitiator::RemoteOffered => self.context.next_holder_htlc_id,
- },
- next_counterparty_htlc_id: match htlc.origin {
- HTLCInitiator::LocalOffered => self.context.next_counterparty_htlc_id,
- HTLCInitiator::RemoteOffered => self.context.next_counterparty_htlc_id + 1,
- },
- feerate: self.context.feerate_per_kw,
- };
- *self.context.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
- }
- res
+ self.context.counterparty_prev_commitment_point = self.context.counterparty_cur_commitment_point;
+ self.context.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
+
+ log_info!(logger, "Received channel_ready from peer for channel {}", log_bytes!(self.context.channel_id()));
+
+ Ok(self.get_announcement_sigs(node_signer, genesis_block_hash, user_config, best_block.height(), logger))
}
pub fn update_add_htlc<F, L: Deref>(&mut self, msg: &msgs::UpdateAddHTLC, mut pending_forward_status: PendingHTLCStatus, create_pending_htlc_status: F, logger: &L) -> Result<(), ChannelError>
return Err(ChannelError::Close(format!("Remote side tried to send less than our minimum HTLC value. Lower limit: ({}). Actual: ({})", self.context.holder_htlc_minimum_msat, msg.amount_msat)));
}
- let inbound_stats = self.get_inbound_pending_htlc_stats(None);
- let outbound_stats = self.get_outbound_pending_htlc_stats(None);
+ let inbound_stats = self.context.get_inbound_pending_htlc_stats(None);
+ let outbound_stats = self.context.get_outbound_pending_htlc_stats(None);
if inbound_stats.pending_htlcs + 1 > self.context.holder_max_accepted_htlcs as u32 {
return Err(ChannelError::Close(format!("Remote tried to push more than our max accepted HTLCs ({})", self.context.holder_max_accepted_htlcs)));
}
let (htlc_timeout_dust_limit, htlc_success_dust_limit) = if self.context.opt_anchors() {
(0, 0)
} else {
- let dust_buffer_feerate = self.get_dust_buffer_feerate(None) as u64;
+ let dust_buffer_feerate = self.context.get_dust_buffer_feerate(None) as u64;
(dust_buffer_feerate * htlc_timeout_tx_weight(false) / 1000,
dust_buffer_feerate * htlc_success_tx_weight(false) / 1000)
};
let exposure_dust_limit_timeout_sats = htlc_timeout_dust_limit + self.context.counterparty_dust_limit_satoshis;
if msg.amount_msat / 1000 < exposure_dust_limit_timeout_sats {
let on_counterparty_tx_dust_htlc_exposure_msat = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat + msg.amount_msat;
- if on_counterparty_tx_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
+ if on_counterparty_tx_dust_htlc_exposure_msat > self.context.get_max_dust_htlc_exposure_msat() {
log_info!(logger, "Cannot accept value that would put our exposure to dust HTLCs at {} over the limit {} on counterparty commitment tx",
- on_counterparty_tx_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat());
+ on_counterparty_tx_dust_htlc_exposure_msat, self.context.get_max_dust_htlc_exposure_msat());
pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
}
}
let exposure_dust_limit_success_sats = htlc_success_dust_limit + self.context.holder_dust_limit_satoshis;
if msg.amount_msat / 1000 < exposure_dust_limit_success_sats {
let on_holder_tx_dust_htlc_exposure_msat = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat + msg.amount_msat;
- if on_holder_tx_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
+ if on_holder_tx_dust_htlc_exposure_msat > self.context.get_max_dust_htlc_exposure_msat() {
log_info!(logger, "Cannot accept value that would put our exposure to dust HTLCs at {} over the limit {} on holder commitment tx",
- on_holder_tx_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat());
+ on_holder_tx_dust_htlc_exposure_msat, self.context.get_max_dust_htlc_exposure_msat());
pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
}
}
// Check that the remote can afford to pay for this HTLC on-chain at the current
// feerate_per_kw, while maintaining their channel reserve (as required by the spec).
- let remote_commit_tx_fee_msat = if self.is_outbound() { 0 } else {
+ let remote_commit_tx_fee_msat = if self.context.is_outbound() { 0 } else {
let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
- self.next_remote_commit_tx_fee_msat(htlc_candidate, None) // Don't include the extra fee spike buffer HTLC in calculations
+ self.context.next_remote_commit_tx_fee_msat(htlc_candidate, None) // Don't include the extra fee spike buffer HTLC in calculations
};
if pending_remote_value_msat - msg.amount_msat < remote_commit_tx_fee_msat {
return Err(ChannelError::Close("Remote HTLC add would not leave enough to pay for fees".to_owned()));
return Err(ChannelError::Close("Remote HTLC add would put them under remote reserve value".to_owned()));
}
- if !self.is_outbound() {
+ if !self.context.is_outbound() {
// `2 *` and `Some(())` is for the fee spike buffer we keep for the remote. This deviates from
// the spec because in the spec, the fee spike buffer requirement doesn't exist on the
// receiver's side, only on the sender's.
// still be able to afford adding this HTLC plus one more future HTLC, regardless of being
// sensitive to fee spikes.
let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
- let remote_fee_cost_incl_stuck_buffer_msat = 2 * self.next_remote_commit_tx_fee_msat(htlc_candidate, Some(()));
+ let remote_fee_cost_incl_stuck_buffer_msat = 2 * self.context.next_remote_commit_tx_fee_msat(htlc_candidate, Some(()));
if pending_remote_value_msat - msg.amount_msat - self.context.holder_selected_channel_reserve_satoshis * 1000 < remote_fee_cost_incl_stuck_buffer_msat {
// Note that if the pending_forward_status is not updated here, then it's because we're already failing
// the HTLC, i.e. its status is already set to failing.
- log_info!(logger, "Attempting to fail HTLC due to fee spike buffer violation in channel {}. Rebalancing is required.", log_bytes!(self.channel_id()));
+ log_info!(logger, "Attempting to fail HTLC due to fee spike buffer violation in channel {}. Rebalancing is required.", log_bytes!(self.context.channel_id()));
pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
}
} else {
// Check that they won't violate our local required channel reserve by adding this HTLC.
let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
- let local_commit_tx_fee_msat = self.next_local_commit_tx_fee_msat(htlc_candidate, None);
+ let local_commit_tx_fee_msat = self.context.next_local_commit_tx_fee_msat(htlc_candidate, None);
if self.context.value_to_self_msat < self.context.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000 + local_commit_tx_fee_msat {
return Err(ChannelError::Close("Cannot accept HTLC that would put our balance under counterparty-announced channel reserve value".to_owned()));
}
return Err(ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds".to_owned()));
}
- let funding_script = self.get_funding_redeemscript();
+ let funding_script = self.context.get_funding_redeemscript();
- let keys = self.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
+ let keys = self.context.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
- let commitment_stats = self.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &keys, true, false, logger);
+ let commitment_stats = self.context.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &keys, true, false, logger);
let commitment_txid = {
let trusted_tx = commitment_stats.tx.trust();
let bitcoin_tx = trusted_tx.built_transaction();
log_trace!(logger, "Checking commitment tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} in channel {}",
log_bytes!(msg.signature.serialize_compact()[..]),
- log_bytes!(self.counterparty_funding_pubkey().serialize()), encode::serialize_hex(&bitcoin_tx.transaction),
- log_bytes!(sighash[..]), encode::serialize_hex(&funding_script), log_bytes!(self.channel_id()));
- if let Err(_) = self.context.secp_ctx.verify_ecdsa(&sighash, &msg.signature, &self.counterparty_funding_pubkey()) {
+ log_bytes!(self.context.counterparty_funding_pubkey().serialize()), encode::serialize_hex(&bitcoin_tx.transaction),
+ log_bytes!(sighash[..]), encode::serialize_hex(&funding_script), log_bytes!(self.context.channel_id()));
+ if let Err(_) = self.context.secp_ctx.verify_ecdsa(&sighash, &msg.signature, &self.context.counterparty_funding_pubkey()) {
return Err(ChannelError::Close("Invalid commitment tx signature from peer".to_owned()));
}
bitcoin_tx.txid
update_state == FeeUpdateState::RemoteAnnounced
} else { false };
if update_fee {
- debug_assert!(!self.is_outbound());
+ debug_assert!(!self.context.is_outbound());
let counterparty_reserve_we_require_msat = self.context.holder_selected_channel_reserve_satoshis * 1000;
if commitment_stats.remote_balance_msat < commitment_stats.total_fee_sat * 1000 + counterparty_reserve_we_require_msat {
return Err(ChannelError::Close("Funding remote cannot afford proposed new fee".to_owned()));
}
#[cfg(any(test, fuzzing))]
{
- if self.is_outbound() {
+ if self.context.is_outbound() {
let projected_commit_tx_info = self.context.next_local_commitment_tx_fee_info_cached.lock().unwrap().take();
*self.context.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
if let Some(info) = projected_commit_tx_info {
for (idx, (htlc, mut source_opt)) in htlcs_cloned.drain(..).enumerate() {
if let Some(_) = htlc.transaction_output_index {
let htlc_tx = chan_utils::build_htlc_transaction(&commitment_txid, commitment_stats.feerate_per_kw,
- self.get_counterparty_selected_contest_delay().unwrap(), &htlc, self.context.opt_anchors(),
+ self.context.get_counterparty_selected_contest_delay().unwrap(), &htlc, self.context.opt_anchors(),
false, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, self.context.opt_anchors(), &keys);
let htlc_sighash = hash_to_message!(&sighash::SighashCache::new(&htlc_tx).segwit_signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, htlc_sighashtype).unwrap()[..]);
log_trace!(logger, "Checking HTLC tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} in channel {}.",
log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(keys.countersignatory_htlc_key.serialize()),
- encode::serialize_hex(&htlc_tx), log_bytes!(htlc_sighash[..]), encode::serialize_hex(&htlc_redeemscript), log_bytes!(self.channel_id()));
+ encode::serialize_hex(&htlc_tx), log_bytes!(htlc_sighash[..]), encode::serialize_hex(&htlc_redeemscript), log_bytes!(self.context.channel_id()));
if let Err(_) = self.context.secp_ctx.verify_ecdsa(&htlc_sighash, &msg.htlc_signatures[idx], &keys.countersignatory_htlc_key) {
return Err(ChannelError::Close("Invalid HTLC tx signature from peer".to_owned()));
}
commitment_stats.tx,
msg.signature,
msg.htlc_signatures.clone(),
- &self.get_holder_pubkeys().funding_pubkey,
- self.counterparty_funding_pubkey()
+ &self.context.get_holder_pubkeys().funding_pubkey,
+ self.context.counterparty_funding_pubkey()
);
self.context.holder_signer.validate_holder_commitment(&holder_commitment_tx, commitment_stats.preimages)
} else { false };
log_debug!(logger, "Received valid commitment_signed from peer in channel {}, updating HTLC state and responding with{} a revoke_and_ack.",
- log_bytes!(self.channel_id()), if need_commitment_signed { " our own commitment_signed and" } else { "" });
+ log_bytes!(self.context.channel_id()), if need_commitment_signed { " our own commitment_signed and" } else { "" });
self.monitor_updating_paused(true, need_commitment_signed, false, Vec::new(), Vec::new(), Vec::new());
return Ok(self.push_ret_blockable_mon_update(monitor_update));
}
assert_eq!(self.context.channel_state & ChannelState::MonitorUpdateInProgress as u32, 0);
if self.context.holding_cell_htlc_updates.len() != 0 || self.context.holding_cell_update_fee.is_some() {
log_trace!(logger, "Freeing holding cell with {} HTLC updates{} in channel {}", self.context.holding_cell_htlc_updates.len(),
- if self.context.holding_cell_update_fee.is_some() { " and a fee update" } else { "" }, log_bytes!(self.channel_id()));
+ if self.context.holding_cell_update_fee.is_some() { " and a fee update" } else { "" }, log_bytes!(self.context.channel_id()));
let mut monitor_update = ChannelMonitorUpdate {
update_id: self.context.latest_monitor_update_id + 1, // We don't increment this yet!
match e {
ChannelError::Ignore(ref msg) => {
log_info!(logger, "Failed to send HTLC with payment_hash {} due to {} in channel {}",
- log_bytes!(payment_hash.0), msg, log_bytes!(self.channel_id()));
+ log_bytes!(payment_hash.0), msg, log_bytes!(self.context.channel_id()));
// If we fail to send here, then this HTLC should
// be failed backwards. Failing to send here
// indicates that this HTLC may keep being put back
monitor_update.updates.append(&mut additional_update.updates);
log_debug!(logger, "Freeing holding cell in channel {} resulted in {}{} HTLCs added, {} HTLCs fulfilled, and {} HTLCs failed.",
- log_bytes!(self.channel_id()), if update_fee.is_some() { "a fee update, " } else { "" },
+ log_bytes!(self.context.channel_id()), if update_fee.is_some() { "a fee update, " } else { "" },
update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len());
self.monitor_updating_paused(false, true, false, Vec::new(), Vec::new(), Vec::new());
self.context.announcement_sigs_state = AnnouncementSigsState::PeerReceived;
}
- log_trace!(logger, "Updating HTLCs on receipt of RAA in channel {}...", log_bytes!(self.channel_id()));
+ log_trace!(logger, "Updating HTLCs on receipt of RAA in channel {}...", log_bytes!(self.context.channel_id()));
let mut to_forward_infos = Vec::new();
let mut revoked_htlcs = Vec::new();
let mut finalized_claimed_htlcs = Vec::new();
if let Some((feerate, update_state)) = self.context.pending_update_fee {
match update_state {
FeeUpdateState::Outbound => {
- debug_assert!(self.is_outbound());
+ debug_assert!(self.context.is_outbound());
log_trace!(logger, " ...promoting outbound fee update {} to Committed", feerate);
self.context.feerate_per_kw = feerate;
self.context.pending_update_fee = None;
},
- FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); },
+ FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.context.is_outbound()); },
FeeUpdateState::AwaitingRemoteRevokeToAnnounce => {
- debug_assert!(!self.is_outbound());
+ debug_assert!(!self.context.is_outbound());
log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce fee update {} to Committed", feerate);
require_commitment = true;
self.context.feerate_per_kw = feerate;
self.context.monitor_pending_forwards.append(&mut to_forward_infos);
self.context.monitor_pending_failures.append(&mut revoked_htlcs);
self.context.monitor_pending_finalized_fulfills.append(&mut finalized_claimed_htlcs);
- log_debug!(logger, "Received a valid revoke_and_ack for channel {} but awaiting a monitor update resolution to reply.", log_bytes!(self.channel_id()));
+ log_debug!(logger, "Received a valid revoke_and_ack for channel {} but awaiting a monitor update resolution to reply.", log_bytes!(self.context.channel_id()));
return Ok((Vec::new(), self.push_ret_blockable_mon_update(monitor_update)));
}
monitor_update.updates.append(&mut additional_update.updates);
log_debug!(logger, "Received a valid revoke_and_ack for channel {}. Responding with a commitment update with {} HTLCs failed.",
- log_bytes!(self.channel_id()), update_fail_htlcs.len() + update_fail_malformed_htlcs.len());
+ log_bytes!(self.context.channel_id()), update_fail_htlcs.len() + update_fail_malformed_htlcs.len());
self.monitor_updating_paused(false, true, false, to_forward_infos, revoked_htlcs, finalized_claimed_htlcs);
Ok((htlcs_to_fail, self.push_ret_blockable_mon_update(monitor_update)))
} else {
- log_debug!(logger, "Received a valid revoke_and_ack for channel {} with no reply necessary.", log_bytes!(self.channel_id()));
+ log_debug!(logger, "Received a valid revoke_and_ack for channel {} with no reply necessary.", log_bytes!(self.context.channel_id()));
self.monitor_updating_paused(false, false, false, to_forward_infos, revoked_htlcs, finalized_claimed_htlcs);
Ok((htlcs_to_fail, self.push_ret_blockable_mon_update(monitor_update)))
}
/// You MUST call [`Self::send_commitment_no_state_update`] prior to any other calls on this
/// [`Channel`] if `force_holding_cell` is false.
fn send_update_fee<L: Deref>(&mut self, feerate_per_kw: u32, mut force_holding_cell: bool, logger: &L) -> Option<msgs::UpdateFee> where L::Target: Logger {
- if !self.is_outbound() {
+ if !self.context.is_outbound() {
panic!("Cannot send fee from inbound channel");
}
- if !self.is_usable() {
+ if !self.context.is_usable() {
panic!("Cannot update fee until channel is fully established and we haven't started shutting down");
}
- if !self.is_live() {
+ if !self.context.is_live() {
panic!("Cannot update fee while peer is disconnected/we're awaiting a monitor update (ChannelManager should have caught this)");
}
// Before proposing a feerate update, check that we can actually afford the new fee.
- let inbound_stats = self.get_inbound_pending_htlc_stats(Some(feerate_per_kw));
- let outbound_stats = self.get_outbound_pending_htlc_stats(Some(feerate_per_kw));
- let keys = self.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
- let commitment_stats = self.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &keys, true, true, logger);
- let buffer_fee_msat = Channel::<Signer>::commit_tx_fee_sat(feerate_per_kw, commitment_stats.num_nondust_htlcs + outbound_stats.on_holder_tx_holding_cell_htlcs_count as usize + CONCURRENT_INBOUND_HTLC_FEE_BUFFER as usize, self.context.opt_anchors()) * 1000;
+ let inbound_stats = self.context.get_inbound_pending_htlc_stats(Some(feerate_per_kw));
+ let outbound_stats = self.context.get_outbound_pending_htlc_stats(Some(feerate_per_kw));
+ let keys = self.context.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
+ let commitment_stats = self.context.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &keys, true, true, logger);
+ let buffer_fee_msat = commit_tx_fee_sat(feerate_per_kw, commitment_stats.num_nondust_htlcs + outbound_stats.on_holder_tx_holding_cell_htlcs_count as usize + CONCURRENT_INBOUND_HTLC_FEE_BUFFER as usize, self.context.opt_anchors()) * 1000;
let holder_balance_msat = commitment_stats.local_balance_msat - outbound_stats.holding_cell_msat;
if holder_balance_msat < buffer_fee_msat + self.context.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000 {
//TODO: auto-close after a number of failures?
// Note, we evaluate pending htlc "preemptive" trimmed-to-dust threshold at the proposed `feerate_per_kw`.
let holder_tx_dust_exposure = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
let counterparty_tx_dust_exposure = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat;
- if holder_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
+ if holder_tx_dust_exposure > self.context.get_max_dust_htlc_exposure_msat() {
log_debug!(logger, "Cannot afford to send new feerate at {} without infringing max dust htlc exposure", feerate_per_kw);
return None;
}
- if counterparty_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
+ if counterparty_tx_dust_exposure > self.context.get_max_dust_htlc_exposure_msat() {
log_debug!(logger, "Cannot afford to send new feerate at {} without infringing max dust htlc exposure", feerate_per_kw);
return None;
}
if let Some((_, update_state)) = self.context.pending_update_fee {
if update_state == FeeUpdateState::RemoteAnnounced {
- debug_assert!(!self.is_outbound());
+ debug_assert!(!self.context.is_outbound());
self.context.pending_update_fee = None;
}
}
self.context.sent_message_awaiting_response = None;
self.context.channel_state |= ChannelState::PeerDisconnected as u32;
- log_trace!(logger, "Peer disconnection resulted in {} remote-announced HTLC drops on channel {}", inbound_drop_count, log_bytes!(self.channel_id()));
+ log_trace!(logger, "Peer disconnection resulted in {} remote-announced HTLC drops on channel {}", inbound_drop_count, log_bytes!(self.context.channel_id()));
}
/// Indicates that a ChannelMonitor update is in progress and has not yet been fully persisted.
// (re-)broadcast the funding transaction as we may have declined to broadcast it when we
// first received the funding_signed.
let mut funding_broadcastable =
- if self.is_outbound() && self.context.channel_state & !MULTI_STATE_FLAGS >= ChannelState::FundingSent as u32 {
+ if self.context.is_outbound() && self.context.channel_state & !MULTI_STATE_FLAGS >= ChannelState::FundingSent as u32 {
self.context.funding_transaction.take()
} else { None };
// That said, if the funding transaction is already confirmed (ie we're active with a
// the funding transaction confirmed before the monitor was persisted, or
// * a 0-conf channel and intended to send the channel_ready before any broadcast at all.
let channel_ready = if self.context.monitor_pending_channel_ready {
- assert!(!self.is_outbound() || self.context.minimum_depth == Some(0),
+ assert!(!self.context.is_outbound() || self.context.minimum_depth == Some(0),
"Funding transaction broadcast by the local client before it should have - LDK didn't do it!");
self.context.monitor_pending_channel_ready = false;
let next_per_commitment_point = self.context.holder_signer.get_per_commitment_point(self.context.cur_holder_commitment_transaction_number, &self.context.secp_ctx);
Some(msgs::ChannelReady {
- channel_id: self.channel_id(),
+ channel_id: self.context.channel_id(),
next_per_commitment_point,
short_channel_id_alias: Some(self.context.outbound_scid_alias),
})
self.context.monitor_pending_commitment_signed = false;
let order = self.context.resend_order.clone();
log_debug!(logger, "Restored monitor updating in channel {} resulting in {}{} commitment update and {} RAA, with {} first",
- log_bytes!(self.channel_id()), if funding_broadcastable.is_some() { "a funding broadcastable, " } else { "" },
+ log_bytes!(self.context.channel_id()), if funding_broadcastable.is_some() { "a funding broadcastable, " } else { "" },
if commitment_update.is_some() { "a" } else { "no" }, if raa.is_some() { "an" } else { "no" },
match order { RAACommitmentOrder::CommitmentFirst => "commitment", RAACommitmentOrder::RevokeAndACKFirst => "RAA"});
MonitorRestoreUpdates {
pub fn update_fee<F: Deref, L: Deref>(&mut self, fee_estimator: &LowerBoundedFeeEstimator<F>, msg: &msgs::UpdateFee, logger: &L) -> Result<(), ChannelError>
where F::Target: FeeEstimator, L::Target: Logger
{
- if self.is_outbound() {
+ if self.context.is_outbound() {
return Err(ChannelError::Close("Non-funding remote tried to update channel fee".to_owned()));
}
if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish".to_owned()));
}
Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw, Some(self.context.feerate_per_kw), logger)?;
- let feerate_over_dust_buffer = msg.feerate_per_kw > self.get_dust_buffer_feerate(None);
+ let feerate_over_dust_buffer = msg.feerate_per_kw > self.context.get_dust_buffer_feerate(None);
self.context.pending_update_fee = Some((msg.feerate_per_kw, FeeUpdateState::RemoteAnnounced));
self.context.update_time_counter += 1;
// `get_dust_buffer_feerate` considers the `pending_update_fee` status), check that we
// won't be pushed over our dust exposure limit by the feerate increase.
if feerate_over_dust_buffer {
- let inbound_stats = self.get_inbound_pending_htlc_stats(None);
- let outbound_stats = self.get_outbound_pending_htlc_stats(None);
+ let inbound_stats = self.context.get_inbound_pending_htlc_stats(None);
+ let outbound_stats = self.context.get_outbound_pending_htlc_stats(None);
let holder_tx_dust_exposure = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
let counterparty_tx_dust_exposure = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat;
- if holder_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
+ if holder_tx_dust_exposure > self.context.get_max_dust_htlc_exposure_msat() {
return Err(ChannelError::Close(format!("Peer sent update_fee with a feerate ({}) which may over-expose us to dust-in-flight on our own transactions (totaling {} msat)",
msg.feerate_per_kw, holder_tx_dust_exposure)));
}
- if counterparty_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
+ if counterparty_tx_dust_exposure > self.context.get_max_dust_htlc_exposure_msat() {
return Err(ChannelError::Close(format!("Peer sent update_fee with a feerate ({}) which may over-expose us to dust-in-flight on our counterparty's transactions (totaling {} msat)",
msg.feerate_per_kw, counterparty_tx_dust_exposure)));
}
for htlc in self.context.pending_outbound_htlcs.iter() {
if let &OutboundHTLCState::LocalAnnounced(ref onion_packet) = &htlc.state {
update_add_htlcs.push(msgs::UpdateAddHTLC {
- channel_id: self.channel_id(),
+ channel_id: self.context.channel_id(),
htlc_id: htlc.htlc_id,
amount_msat: htlc.amount_msat,
payment_hash: htlc.payment_hash,
match reason {
&InboundHTLCRemovalReason::FailRelay(ref err_packet) => {
update_fail_htlcs.push(msgs::UpdateFailHTLC {
- channel_id: self.channel_id(),
+ channel_id: self.context.channel_id(),
htlc_id: htlc.htlc_id,
reason: err_packet.clone()
});
},
&InboundHTLCRemovalReason::FailMalformed((ref sha256_of_onion, ref failure_code)) => {
update_fail_malformed_htlcs.push(msgs::UpdateFailMalformedHTLC {
- channel_id: self.channel_id(),
+ channel_id: self.context.channel_id(),
htlc_id: htlc.htlc_id,
sha256_of_onion: sha256_of_onion.clone(),
failure_code: failure_code.clone(),
},
&InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
update_fulfill_htlcs.push(msgs::UpdateFulfillHTLC {
- channel_id: self.channel_id(),
+ channel_id: self.context.channel_id(),
htlc_id: htlc.htlc_id,
payment_preimage: payment_preimage.clone(),
});
}
}
- let update_fee = if self.is_outbound() && self.context.pending_update_fee.is_some() {
+ let update_fee = if self.context.is_outbound() && self.context.pending_update_fee.is_some() {
Some(msgs::UpdateFee {
- channel_id: self.channel_id(),
+ channel_id: self.context.channel_id(),
feerate_per_kw: self.context.pending_update_fee.unwrap().0,
})
} else { None };
log_trace!(logger, "Regenerated latest commitment update in channel {} with{} {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
- log_bytes!(self.channel_id()), if update_fee.is_some() { " update_fee," } else { "" },
+ log_bytes!(self.context.channel_id()), if update_fee.is_some() { " update_fee," } else { "" },
update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len(), update_fail_malformed_htlcs.len());
msgs::CommitmentUpdate {
update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, update_fail_malformed_htlcs, update_fee,
let next_per_commitment_point = self.context.holder_signer.get_per_commitment_point(self.context.cur_holder_commitment_transaction_number, &self.context.secp_ctx);
return Ok(ReestablishResponses {
channel_ready: Some(msgs::ChannelReady {
- channel_id: self.channel_id(),
+ channel_id: self.context.channel_id(),
next_per_commitment_point,
short_channel_id_alias: Some(self.context.outbound_scid_alias),
}),
// We should never have to worry about MonitorUpdateInProgress resending ChannelReady
let next_per_commitment_point = self.context.holder_signer.get_per_commitment_point(self.context.cur_holder_commitment_transaction_number, &self.context.secp_ctx);
Some(msgs::ChannelReady {
- channel_id: self.channel_id(),
+ channel_id: self.context.channel_id(),
next_per_commitment_point,
short_channel_id_alias: Some(self.context.outbound_scid_alias),
})
if msg.next_local_commitment_number == next_counterparty_commitment_number {
if required_revoke.is_some() {
- log_debug!(logger, "Reconnected channel {} with only lost outbound RAA", log_bytes!(self.channel_id()));
+ log_debug!(logger, "Reconnected channel {} with only lost outbound RAA", log_bytes!(self.context.channel_id()));
} else {
- log_debug!(logger, "Reconnected channel {} with no loss", log_bytes!(self.channel_id()));
+ log_debug!(logger, "Reconnected channel {} with no loss", log_bytes!(self.context.channel_id()));
}
Ok(ReestablishResponses {
})
} else if msg.next_local_commitment_number == next_counterparty_commitment_number - 1 {
if required_revoke.is_some() {
- log_debug!(logger, "Reconnected channel {} with lost outbound RAA and lost remote commitment tx", log_bytes!(self.channel_id()));
+ log_debug!(logger, "Reconnected channel {} with lost outbound RAA and lost remote commitment tx", log_bytes!(self.context.channel_id()));
} else {
- log_debug!(logger, "Reconnected channel {} with only lost remote commitment tx", log_bytes!(self.channel_id()));
+ log_debug!(logger, "Reconnected channel {} with only lost remote commitment tx", log_bytes!(self.context.channel_id()));
}
if self.context.channel_state & (ChannelState::MonitorUpdateInProgress as u32) != 0 {
// If we fail to come to consensus, we'll have to force-close.
let mut proposed_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Background);
let normal_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Normal);
- let mut proposed_max_feerate = if self.is_outbound() { normal_feerate } else { u32::max_value() };
+ let mut proposed_max_feerate = if self.context.is_outbound() { normal_feerate } else { u32::max_value() };
// The spec requires that (when the channel does not have anchors) we only send absolute
// channel fees no greater than the absolute channel fee on the current commitment
// some force-closure by old nodes, but we wanted to close the channel anyway.
if let Some(target_feerate) = self.context.target_closing_feerate_sats_per_kw {
- let min_feerate = if self.is_outbound() { target_feerate } else { cmp::min(self.context.feerate_per_kw, target_feerate) };
+ let min_feerate = if self.context.is_outbound() { target_feerate } else { cmp::min(self.context.feerate_per_kw, target_feerate) };
proposed_feerate = cmp::max(proposed_feerate, min_feerate);
proposed_max_feerate = cmp::max(proposed_max_feerate, min_feerate);
}
// if the funders' output is dust we have to know the absolute fee we're going to use.
let tx_weight = self.get_closing_transaction_weight(Some(&self.get_closing_scriptpubkey()), Some(self.context.counterparty_shutdown_scriptpubkey.as_ref().unwrap()));
let proposed_total_fee_satoshis = proposed_feerate as u64 * tx_weight / 1000;
- let proposed_max_total_fee_satoshis = if self.is_outbound() {
+ let proposed_max_total_fee_satoshis = if self.context.is_outbound() {
// We always add force_close_avoidance_max_fee_satoshis to our normal
// feerate-calculated fee, but allow the max to be overridden if we're using a
// target feerate-calculated fee.
return Ok((None, None));
}
- if !self.is_outbound() {
+ if !self.context.is_outbound() {
if let Some(msg) = &self.context.pending_counterparty_closing_signed.take() {
return self.closing_signed(fee_estimator, &msg);
}
tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
- let funding_key = self.get_holder_pubkeys().funding_pubkey.serialize();
- let counterparty_funding_key = self.counterparty_funding_pubkey().serialize();
+ let funding_key = self.context.get_holder_pubkeys().funding_pubkey.serialize();
+ let counterparty_funding_key = self.context.counterparty_funding_pubkey().serialize();
let mut holder_sig = sig.serialize_der().to_vec();
holder_sig.push(EcdsaSighashType::All as u8);
let mut cp_sig = counterparty_sig.serialize_der().to_vec();
tx.input[0].witness.push(holder_sig);
}
- tx.input[0].witness.push(self.get_funding_redeemscript().into_bytes());
+ tx.input[0].witness.push(self.context.get_funding_redeemscript().into_bytes());
tx
}
return Err(ChannelError::Close("Remote tried to send us a closing tx with > 21 million BTC fee".to_owned()));
}
- if self.is_outbound() && self.context.last_sent_closing_fee.is_none() {
+ if self.context.is_outbound() && self.context.last_sent_closing_fee.is_none() {
return Err(ChannelError::Close("Remote tried to send a closing_signed when we were supposed to propose the first one".to_owned()));
}
return Ok((None, None));
}
- let funding_redeemscript = self.get_funding_redeemscript();
+ let funding_redeemscript = self.context.get_funding_redeemscript();
let (mut closing_tx, used_total_fee) = self.build_closing_transaction(msg.fee_satoshis, false);
if used_total_fee != msg.fee_satoshis {
return Err(ChannelError::Close(format!("Remote sent us a closing_signed with a fee other than the value they can claim. Fee in message: {}. Actual closing tx fee: {}", msg.fee_satoshis, used_total_fee)));
}
let sighash = closing_tx.trust().get_sighash_all(&funding_redeemscript, self.context.channel_value_satoshis);
- match self.context.secp_ctx.verify_ecdsa(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
+ match self.context.secp_ctx.verify_ecdsa(&sighash, &msg.signature, &self.context.get_counterparty_pubkeys().funding_pubkey) {
Ok(_) => {},
Err(_e) => {
// The remote end may have decided to revoke their output due to inconsistent dust
// limits, so check for that case by re-checking the signature here.
closing_tx = self.build_closing_transaction(msg.fee_satoshis, true).0;
let sighash = closing_tx.trust().get_sighash_all(&funding_redeemscript, self.context.channel_value_satoshis);
- secp_check!(self.context.secp_ctx.verify_ecdsa(&sighash, &msg.signature, self.counterparty_funding_pubkey()), "Invalid closing tx signature from peer".to_owned());
+ secp_check!(self.context.secp_ctx.verify_ecdsa(&sighash, &msg.signature, self.context.counterparty_funding_pubkey()), "Invalid closing tx signature from peer".to_owned());
},
};
return Err(ChannelError::Warn(format!("Unable to come to consensus about closing feerate, remote's min fee ({} sat) was greater than our max fee ({} sat)", min_fee_satoshis, our_max_fee)));
}
- if !self.is_outbound() {
+ if !self.context.is_outbound() {
// They have to pay, so pick the highest fee in the overlapping range.
// We should never set an upper bound aside from their full balance
debug_assert_eq!(our_max_fee, self.context.channel_value_satoshis - (self.context.value_to_self_msat + 999) / 1000);
}
}
- // Public utilities:
-
- pub fn channel_id(&self) -> [u8; 32] {
- self.context.channel_id
- }
-
- // Return the `temporary_channel_id` used during channel establishment.
- //
- // Will return `None` for channels created prior to LDK version 0.0.115.
- pub fn temporary_channel_id(&self) -> Option<[u8; 32]> {
- self.context.temporary_channel_id
- }
-
- pub fn minimum_depth(&self) -> Option<u32> {
- self.context.minimum_depth
- }
-
- /// Gets the "user_id" value passed into the construction of this channel. It has no special
- /// meaning and exists only to allow users to have a persistent identifier of a channel.
- pub fn get_user_id(&self) -> u128 {
- self.context.user_id
- }
-
- /// Gets the channel's type
- pub fn get_channel_type(&self) -> &ChannelTypeFeatures {
- &self.context.channel_type
- }
-
- /// Guaranteed to be Some after both ChannelReady messages have been exchanged (and, thus,
- /// is_usable() returns true).
- /// Allowed in any state (including after shutdown)
- pub fn get_short_channel_id(&self) -> Option<u64> {
- self.context.short_channel_id
- }
-
- /// Allowed in any state (including after shutdown)
- pub fn latest_inbound_scid_alias(&self) -> Option<u64> {
- self.context.latest_inbound_scid_alias
- }
-
- /// Allowed in any state (including after shutdown)
- pub fn outbound_scid_alias(&self) -> u64 {
- self.context.outbound_scid_alias
- }
- /// Only allowed immediately after deserialization if get_outbound_scid_alias returns 0,
- /// indicating we were written by LDK prior to 0.0.106 which did not set outbound SCID aliases.
- pub fn set_outbound_scid_alias(&mut self, outbound_scid_alias: u64) {
- assert_eq!(self.context.outbound_scid_alias, 0);
- self.context.outbound_scid_alias = outbound_scid_alias;
- }
-
- /// Returns the funding_txo we either got from our peer, or were given by
- /// get_outbound_funding_created.
- pub fn get_funding_txo(&self) -> Option<OutPoint> {
- self.context.channel_transaction_parameters.funding_outpoint
- }
-
- /// Returns the block hash in which our funding transaction was confirmed.
- pub fn get_funding_tx_confirmed_in(&self) -> Option<BlockHash> {
- self.context.funding_tx_confirmed_in
- }
-
- /// Returns the current number of confirmations on the funding transaction.
- pub fn get_funding_tx_confirmations(&self, height: u32) -> u32 {
- if self.context.funding_tx_confirmation_height == 0 {
- // We either haven't seen any confirmation yet, or observed a reorg.
- return 0;
- }
-
- height.checked_sub(self.context.funding_tx_confirmation_height).map_or(0, |c| c + 1)
- }
-
- fn get_holder_selected_contest_delay(&self) -> u16 {
- self.context.channel_transaction_parameters.holder_selected_contest_delay
- }
-
- fn get_holder_pubkeys(&self) -> &ChannelPublicKeys {
- &self.context.channel_transaction_parameters.holder_pubkeys
- }
-
- pub fn get_counterparty_selected_contest_delay(&self) -> Option<u16> {
- self.context.channel_transaction_parameters.counterparty_parameters
- .as_ref().map(|params| params.selected_contest_delay)
- }
-
- fn get_counterparty_pubkeys(&self) -> &ChannelPublicKeys {
- &self.context.channel_transaction_parameters.counterparty_parameters.as_ref().unwrap().pubkeys
- }
-
- /// Allowed in any state (including after shutdown)
- pub fn get_counterparty_node_id(&self) -> PublicKey {
- self.context.counterparty_node_id
- }
-
- /// Allowed in any state (including after shutdown)
- pub fn get_holder_htlc_minimum_msat(&self) -> u64 {
- self.context.holder_htlc_minimum_msat
- }
-
- /// Allowed in any state (including after shutdown), but will return none before TheirInitSent
- pub fn get_holder_htlc_maximum_msat(&self) -> Option<u64> {
- self.get_htlc_maximum_msat(self.context.holder_max_htlc_value_in_flight_msat)
- }
-
- /// Allowed in any state (including after shutdown)
- pub fn get_announced_htlc_max_msat(&self) -> u64 {
- return cmp::min(
- // Upper bound by capacity. We make it a bit less than full capacity to prevent attempts
- // to use full capacity. This is an effort to reduce routing failures, because in many cases
- // channel might have been used to route very small values (either by honest users or as DoS).
- self.context.channel_value_satoshis * 1000 * 9 / 10,
-
- self.context.counterparty_max_htlc_value_in_flight_msat
- );
- }
-
- /// Allowed in any state (including after shutdown)
- pub fn get_counterparty_htlc_minimum_msat(&self) -> u64 {
- self.context.counterparty_htlc_minimum_msat
- }
-
- /// Allowed in any state (including after shutdown), but will return none before TheirInitSent
- pub fn get_counterparty_htlc_maximum_msat(&self) -> Option<u64> {
- self.get_htlc_maximum_msat(self.context.counterparty_max_htlc_value_in_flight_msat)
- }
-
- fn get_htlc_maximum_msat(&self, party_max_htlc_value_in_flight_msat: u64) -> Option<u64> {
- self.context.counterparty_selected_channel_reserve_satoshis.map(|counterparty_reserve| {
- let holder_reserve = self.context.holder_selected_channel_reserve_satoshis;
- cmp::min(
- (self.context.channel_value_satoshis - counterparty_reserve - holder_reserve) * 1000,
- party_max_htlc_value_in_flight_msat
- )
- })
- }
-
- pub fn get_value_satoshis(&self) -> u64 {
- self.context.channel_value_satoshis
- }
-
- pub fn get_fee_proportional_millionths(&self) -> u32 {
- self.context.config.options.forwarding_fee_proportional_millionths
- }
-
- pub fn get_cltv_expiry_delta(&self) -> u16 {
- cmp::max(self.context.config.options.cltv_expiry_delta, MIN_CLTV_EXPIRY_DELTA)
- }
-
- pub fn get_max_dust_htlc_exposure_msat(&self) -> u64 {
- self.context.config.options.max_dust_htlc_exposure_msat
- }
-
- /// Returns the previous [`ChannelConfig`] applied to this channel, if any.
- pub fn prev_config(&self) -> Option<ChannelConfig> {
- self.context.prev_config.map(|prev_config| prev_config.0)
- }
-
- // Checks whether we should emit a `ChannelPending` event.
- pub(crate) fn should_emit_channel_pending_event(&mut self) -> bool {
- self.is_funding_initiated() && !self.context.channel_pending_event_emitted
- }
-
- // Returns whether we already emitted a `ChannelPending` event.
- pub(crate) fn channel_pending_event_emitted(&self) -> bool {
- self.context.channel_pending_event_emitted
- }
-
- // Remembers that we already emitted a `ChannelPending` event.
- pub(crate) fn set_channel_pending_event_emitted(&mut self) {
- self.context.channel_pending_event_emitted = true;
- }
-
- // Checks whether we should emit a `ChannelReady` event.
- pub(crate) fn should_emit_channel_ready_event(&mut self) -> bool {
- self.is_usable() && !self.context.channel_ready_event_emitted
- }
-
- // Remembers that we already emitted a `ChannelReady` event.
- pub(crate) fn set_channel_ready_event_emitted(&mut self) {
- self.context.channel_ready_event_emitted = true;
- }
-
- /// Tracks the number of ticks elapsed since the previous [`ChannelConfig`] was updated. Once
- /// [`EXPIRE_PREV_CONFIG_TICKS`] is reached, the previous config is considered expired and will
- /// no longer be considered when forwarding HTLCs.
- pub fn maybe_expire_prev_config(&mut self) {
- if self.context.prev_config.is_none() {
- return;
- }
- let prev_config = self.context.prev_config.as_mut().unwrap();
- prev_config.1 += 1;
- if prev_config.1 == EXPIRE_PREV_CONFIG_TICKS {
- self.context.prev_config = None;
- }
- }
-
- /// Returns the current [`ChannelConfig`] applied to the channel.
- pub fn config(&self) -> ChannelConfig {
- self.context.config.options
- }
-
- /// Updates the channel's config. A bool is returned indicating whether the config update
- /// applied resulted in a new ChannelUpdate message.
- pub fn update_config(&mut self, config: &ChannelConfig) -> bool {
- let did_channel_update =
- self.context.config.options.forwarding_fee_proportional_millionths != config.forwarding_fee_proportional_millionths ||
- self.context.config.options.forwarding_fee_base_msat != config.forwarding_fee_base_msat ||
- self.context.config.options.cltv_expiry_delta != config.cltv_expiry_delta;
- if did_channel_update {
- self.context.prev_config = Some((self.context.config.options, 0));
- // Update the counter, which backs the ChannelUpdate timestamp, to allow the relay
- // policy change to propagate throughout the network.
- self.context.update_time_counter += 1;
- }
- self.context.config.options = *config;
- did_channel_update
- }
-
fn internal_htlc_satisfies_config(
&self, htlc: &msgs::UpdateAddHTLC, amt_to_forward: u64, outgoing_cltv_value: u32, config: &ChannelConfig,
) -> Result<(), (&'static str, u16)> {
pub fn htlc_satisfies_config(
&self, htlc: &msgs::UpdateAddHTLC, amt_to_forward: u64, outgoing_cltv_value: u32,
) -> Result<(), (&'static str, u16)> {
- self.internal_htlc_satisfies_config(&htlc, amt_to_forward, outgoing_cltv_value, &self.config())
+ self.internal_htlc_satisfies_config(&htlc, amt_to_forward, outgoing_cltv_value, &self.context.config())
.or_else(|err| {
- if let Some(prev_config) = self.prev_config() {
+ if let Some(prev_config) = self.context.prev_config() {
self.internal_htlc_satisfies_config(htlc, amt_to_forward, outgoing_cltv_value, &prev_config)
} else {
Err(err)
})
}
- pub fn get_feerate_sat_per_1000_weight(&self) -> u32 {
- self.context.feerate_per_kw
- }
-
- pub fn get_dust_buffer_feerate(&self, outbound_feerate_update: Option<u32>) -> u32 {
- // When calculating our exposure to dust HTLCs, we assume that the channel feerate
- // may, at any point, increase by at least 10 sat/vB (i.e 2530 sat/kWU) or 25%,
- // whichever is higher. This ensures that we aren't suddenly exposed to significantly
- // more dust balance if the feerate increases when we have several HTLCs pending
- // which are near the dust limit.
- let mut feerate_per_kw = self.context.feerate_per_kw;
- // If there's a pending update fee, use it to ensure we aren't under-estimating
- // potential feerate updates coming soon.
- if let Some((feerate, _)) = self.context.pending_update_fee {
- feerate_per_kw = cmp::max(feerate_per_kw, feerate);
- }
- if let Some(feerate) = outbound_feerate_update {
- feerate_per_kw = cmp::max(feerate_per_kw, feerate);
- }
- cmp::max(2530, feerate_per_kw * 1250 / 1000)
- }
-
pub fn get_cur_holder_commitment_transaction_number(&self) -> u64 {
self.context.cur_holder_commitment_transaction_number + 1
}
}
}
- /// Allowed in any state (including after shutdown)
- pub fn get_update_time_counter(&self) -> u32 {
- self.context.update_time_counter
- }
-
- pub fn get_latest_monitor_update_id(&self) -> u64 {
- self.context.latest_monitor_update_id
- }
-
- pub fn should_announce(&self) -> bool {
- self.context.config.announced_channel
- }
-
- pub fn is_outbound(&self) -> bool {
- self.context.channel_transaction_parameters.is_outbound_from_holder
- }
-
- /// Gets the fee we'd want to charge for adding an HTLC output to this Channel
- /// Allowed in any state (including after shutdown)
- pub fn get_outbound_forwarding_fee_base_msat(&self) -> u32 {
- self.context.config.options.forwarding_fee_base_msat
- }
-
- /// Returns true if we've ever received a message from the remote end for this Channel
- pub fn have_received_message(&self) -> bool {
- self.context.channel_state > (ChannelState::OurInitSent as u32)
- }
-
- /// Returns true if this channel is fully established and not known to be closing.
- /// Allowed in any state (including after shutdown)
- pub fn is_usable(&self) -> bool {
- let mask = ChannelState::ChannelReady as u32 | BOTH_SIDES_SHUTDOWN_MASK;
- (self.context.channel_state & mask) == (ChannelState::ChannelReady as u32) && !self.context.monitor_pending_channel_ready
- }
-
- /// Returns true if this channel is currently available for use. This is a superset of
- /// is_usable() and considers things like the channel being temporarily disabled.
- /// Allowed in any state (including after shutdown)
- pub fn is_live(&self) -> bool {
- self.is_usable() && (self.context.channel_state & (ChannelState::PeerDisconnected as u32) == 0)
- }
-
/// Returns true if this channel has been marked as awaiting a monitor update to move forward.
/// Allowed in any state (including after shutdown)
pub fn is_awaiting_monitor_update(&self) -> bool {
}
pub fn get_latest_complete_monitor_update_id(&self) -> u64 {
- if self.context.pending_monitor_updates.is_empty() { return self.get_latest_monitor_update_id(); }
+ if self.context.pending_monitor_updates.is_empty() { return self.context.get_latest_monitor_update_id(); }
self.context.pending_monitor_updates[0].update.update_id - 1
}
.filter_map(|upd| if upd.blocked { None } else { Some(&upd.update) })
}
- /// Returns true if funding_created was sent/received.
- pub fn is_funding_initiated(&self) -> bool {
- self.context.channel_state >= ChannelState::FundingSent as u32
- }
-
/// Returns true if the channel is awaiting the persistence of the initial ChannelMonitor.
/// If the channel is outbound, this implies we have not yet broadcasted the funding
/// transaction. If the channel is inbound, this implies simply that the channel has not
// Because deciding we're awaiting initial broadcast spuriously could result in
// funds-loss (as we don't have a monitor, but have the funding transaction confirmed),
// we hard-assert here, even in production builds.
- if self.is_outbound() { assert!(self.context.funding_transaction.is_some()); }
+ if self.context.is_outbound() { assert!(self.context.funding_transaction.is_some()); }
assert!(self.context.monitor_pending_channel_ready);
assert_eq!(self.context.latest_monitor_update_id, 0);
return true;
NS::Target: NodeSigner,
L::Target: Logger
{
- if let Some(funding_txo) = self.get_funding_txo() {
+ if let Some(funding_txo) = self.context.get_funding_txo() {
for &(index_in_block, tx) in txdata.iter() {
// Check if the transaction is the expected funding transaction, and if it is,
// check that it pays the right amount to the right script.
if self.context.funding_tx_confirmation_height == 0 {
if tx.txid() == funding_txo.txid {
let txo_idx = funding_txo.index as usize;
- if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.get_funding_redeemscript().to_v0_p2wsh() ||
+ if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.context.get_funding_redeemscript().to_v0_p2wsh() ||
tx.output[txo_idx].value != self.context.channel_value_satoshis {
- if self.is_outbound() {
+ if self.context.is_outbound() {
// If we generated the funding transaction and it doesn't match what it
// should, the client is really broken and we should just panic and
// tell them off. That said, because hash collisions happen with high
let err_reason = "funding tx had wrong script/value or output index";
return Err(ClosureReason::ProcessingError { err: err_reason.to_owned() });
} else {
- if self.is_outbound() {
+ if self.context.is_outbound() {
for input in tx.input.iter() {
if input.witness.is_empty() {
// We generated a malleable funding transaction, implying we've
}
for inp in tx.input.iter() {
if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
- log_info!(logger, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(self.channel_id()));
+ log_info!(logger, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(self.context.channel_id()));
return Err(ClosureReason::CommitmentTxConfirmed);
}
}
self.context.minimum_depth.unwrap(), funding_tx_confirmations);
return Err(ClosureReason::ProcessingError { err: err_reason });
}
- } else if !self.is_outbound() && self.context.funding_tx_confirmed_in.is_none() &&
+ } else if !self.context.is_outbound() && self.context.funding_tx_confirmed_in.is_none() &&
height >= self.context.channel_creation_height + FUNDING_CONF_DEADLINE_BLOCKS {
log_info!(logger, "Closing channel {} due to funding timeout", log_bytes!(self.context.channel_id));
// If funding_tx_confirmed_in is unset, the channel must not be active
// something in the handler for the message that prompted this message):
pub fn get_open_channel(&self, chain_hash: BlockHash) -> msgs::OpenChannel {
- if !self.is_outbound() {
+ if !self.context.is_outbound() {
panic!("Tried to open a channel for an inbound channel?");
}
if self.context.channel_state != ChannelState::OurInitSent as u32 {
}
let first_per_commitment_point = self.context.holder_signer.get_per_commitment_point(self.context.cur_holder_commitment_transaction_number, &self.context.secp_ctx);
- let keys = self.get_holder_pubkeys();
+ let keys = self.context.get_holder_pubkeys();
msgs::OpenChannel {
chain_hash,
channel_reserve_satoshis: self.context.holder_selected_channel_reserve_satoshis,
htlc_minimum_msat: self.context.holder_htlc_minimum_msat,
feerate_per_kw: self.context.feerate_per_kw as u32,
- to_self_delay: self.get_holder_selected_contest_delay(),
+ to_self_delay: self.context.get_holder_selected_contest_delay(),
max_accepted_htlcs: self.context.holder_max_accepted_htlcs,
funding_pubkey: keys.funding_pubkey,
revocation_basepoint: keys.revocation_basepoint,
///
/// [`msgs::AcceptChannel`]: crate::ln::msgs::AcceptChannel
pub fn accept_inbound_channel(&mut self, user_id: u128) -> msgs::AcceptChannel {
- if self.is_outbound() {
+ if self.context.is_outbound() {
panic!("Tried to send accept_channel for an outbound channel?");
}
if self.context.channel_state != (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32) {
/// [`msgs::AcceptChannel`]: crate::ln::msgs::AcceptChannel
fn generate_accept_channel_message(&self) -> msgs::AcceptChannel {
let first_per_commitment_point = self.context.holder_signer.get_per_commitment_point(self.context.cur_holder_commitment_transaction_number, &self.context.secp_ctx);
- let keys = self.get_holder_pubkeys();
+ let keys = self.context.get_holder_pubkeys();
msgs::AcceptChannel {
temporary_channel_id: self.context.channel_id,
channel_reserve_satoshis: self.context.holder_selected_channel_reserve_satoshis,
htlc_minimum_msat: self.context.holder_htlc_minimum_msat,
minimum_depth: self.context.minimum_depth.unwrap(),
- to_self_delay: self.get_holder_selected_contest_delay(),
+ to_self_delay: self.context.get_holder_selected_contest_delay(),
max_accepted_htlcs: self.context.holder_max_accepted_htlcs,
funding_pubkey: keys.funding_pubkey,
revocation_basepoint: keys.revocation_basepoint,
/// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
fn get_outbound_funding_created_signature<L: Deref>(&mut self, logger: &L) -> Result<Signature, ChannelError> where L::Target: Logger {
- let counterparty_keys = self.build_remote_transaction_keys();
- let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.context.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).tx;
+ let counterparty_keys = self.context.build_remote_transaction_keys();
+ let counterparty_initial_commitment_tx = self.context.build_commitment_transaction(self.context.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).tx;
Ok(self.context.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, Vec::new(), &self.context.secp_ctx)
.map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0)
}
/// Do NOT broadcast the funding transaction until after a successful funding_signed call!
/// If an Err is returned, it is a ChannelError::Close.
pub fn get_outbound_funding_created<L: Deref>(&mut self, funding_transaction: Transaction, funding_txo: OutPoint, logger: &L) -> Result<msgs::FundingCreated, ChannelError> where L::Target: Logger {
- if !self.is_outbound() {
+ if !self.context.is_outbound() {
panic!("Tried to create outbound funding_created message on an inbound channel!");
}
if self.context.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
if !self.context.config.announced_channel {
return Err(ChannelError::Ignore("Channel is not available for public announcements".to_owned()));
}
- if !self.is_usable() {
+ if !self.context.is_usable() {
return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement if the channel is not currently usable".to_owned()));
}
let node_id = NodeId::from_pubkey(&node_signer.get_node_id(Recipient::Node)
.map_err(|_| ChannelError::Ignore("Failed to retrieve own public key".to_owned()))?);
- let counterparty_node_id = NodeId::from_pubkey(&self.get_counterparty_node_id());
+ let counterparty_node_id = NodeId::from_pubkey(&self.context.get_counterparty_node_id());
let were_node_one = node_id.as_slice() < counterparty_node_id.as_slice();
let msg = msgs::UnsignedChannelAnnouncement {
features: channelmanager::provided_channel_features(&user_config),
chain_hash,
- short_channel_id: self.get_short_channel_id().unwrap(),
+ short_channel_id: self.context.get_short_channel_id().unwrap(),
node_id_1: if were_node_one { node_id } else { counterparty_node_id },
node_id_2: if were_node_one { counterparty_node_id } else { node_id },
- bitcoin_key_1: NodeId::from_pubkey(if were_node_one { &self.get_holder_pubkeys().funding_pubkey } else { self.counterparty_funding_pubkey() }),
- bitcoin_key_2: NodeId::from_pubkey(if were_node_one { self.counterparty_funding_pubkey() } else { &self.get_holder_pubkeys().funding_pubkey }),
+ bitcoin_key_1: NodeId::from_pubkey(if were_node_one { &self.context.get_holder_pubkeys().funding_pubkey } else { self.context.counterparty_funding_pubkey() }),
+ bitcoin_key_2: NodeId::from_pubkey(if were_node_one { self.context.counterparty_funding_pubkey() } else { &self.context.get_holder_pubkeys().funding_pubkey }),
excess_data: Vec::new(),
};
return None;
}
- if !self.is_usable() {
+ if !self.context.is_usable() {
return None;
}
return None;
}
- log_trace!(logger, "Creating an announcement_signatures message for channel {}", log_bytes!(self.channel_id()));
+ log_trace!(logger, "Creating an announcement_signatures message for channel {}", log_bytes!(self.context.channel_id()));
let announcement = match self.get_channel_announcement(node_signer, genesis_block_hash, user_config) {
Ok(a) => a,
Err(e) => {
self.context.announcement_sigs_state = AnnouncementSigsState::MessageSent;
Some(msgs::AnnouncementSignatures {
- channel_id: self.channel_id(),
- short_channel_id: self.get_short_channel_id().unwrap(),
+ channel_id: self.context.channel_id(),
+ short_channel_id: self.context.get_short_channel_id().unwrap(),
node_signature: our_node_sig,
bitcoin_signature: our_bitcoin_sig,
})
let msghash = hash_to_message!(&Sha256d::hash(&announcement.encode()[..])[..]);
- if self.context.secp_ctx.verify_ecdsa(&msghash, &msg.node_signature, &self.get_counterparty_node_id()).is_err() {
+ if self.context.secp_ctx.verify_ecdsa(&msghash, &msg.node_signature, &self.context.get_counterparty_node_id()).is_err() {
return Err(ChannelError::Close(format!(
"Bad announcement_signatures. Failed to verify node_signature. UnsignedChannelAnnouncement used for verification is {:?}. their_node_key is {:?}",
- &announcement, self.get_counterparty_node_id())));
+ &announcement, self.context.get_counterparty_node_id())));
}
- if self.context.secp_ctx.verify_ecdsa(&msghash, &msg.bitcoin_signature, self.counterparty_funding_pubkey()).is_err() {
+ if self.context.secp_ctx.verify_ecdsa(&msghash, &msg.bitcoin_signature, self.context.counterparty_funding_pubkey()).is_err() {
return Err(ChannelError::Close(format!(
"Bad announcement_signatures. Failed to verify bitcoin_signature. UnsignedChannelAnnouncement used for verification is {:?}. their_bitcoin_key is ({:?})",
- &announcement, self.counterparty_funding_pubkey())));
+ &announcement, self.context.counterparty_funding_pubkey())));
}
self.context.announcement_sigs = Some((msg.node_signature, msg.bitcoin_signature));
let dummy_pubkey = PublicKey::from_slice(&pk).unwrap();
let remote_last_secret = if self.context.cur_counterparty_commitment_transaction_number + 1 < INITIAL_COMMITMENT_NUMBER {
let remote_last_secret = self.context.commitment_secrets.get_secret(self.context.cur_counterparty_commitment_transaction_number + 2).unwrap();
- log_trace!(logger, "Enough info to generate a Data Loss Protect with per_commitment_secret {} for channel {}", log_bytes!(remote_last_secret), log_bytes!(self.channel_id()));
+ log_trace!(logger, "Enough info to generate a Data Loss Protect with per_commitment_secret {} for channel {}", log_bytes!(remote_last_secret), log_bytes!(self.context.channel_id()));
remote_last_secret
} else {
- log_info!(logger, "Sending a data_loss_protect with no previous remote per_commitment_secret for channel {}", log_bytes!(self.channel_id()));
+ log_info!(logger, "Sending a data_loss_protect with no previous remote per_commitment_secret for channel {}", log_bytes!(self.context.channel_id()));
[0;32]
};
self.mark_awaiting_response();
msgs::ChannelReestablish {
- channel_id: self.channel_id(),
+ channel_id: self.context.channel_id(),
// The protocol has two different commitment number concepts - the "commitment
// transaction number", which starts from 0 and counts up, and the "revocation key
// index" which starts at INITIAL_COMMITMENT_NUMBER and counts down. We track
return Err(ChannelError::Ignore("Cannot send 0-msat HTLC".to_owned()));
}
- let available_balances = self.get_available_balances();
+ let available_balances = self.context.get_available_balances();
if amount_msat < available_balances.next_outbound_htlc_minimum_msat {
return Err(ChannelError::Ignore(format!("Cannot send less than our next-HTLC minimum - {} msat",
available_balances.next_outbound_htlc_minimum_msat)));
}
if let Some((feerate, update_state)) = self.context.pending_update_fee {
if update_state == FeeUpdateState::AwaitingRemoteRevokeToAnnounce {
- debug_assert!(!self.is_outbound());
+ debug_assert!(!self.context.is_outbound());
log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce fee update {} to Committed", feerate);
self.context.feerate_per_kw = feerate;
self.context.pending_update_fee = None;
}
fn build_commitment_no_state_update<L: Deref>(&self, logger: &L) -> (Txid, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>) where L::Target: Logger {
- let counterparty_keys = self.build_remote_transaction_keys();
- let commitment_stats = self.build_commitment_transaction(self.context.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, logger);
+ let counterparty_keys = self.context.build_remote_transaction_keys();
+ let commitment_stats = self.context.build_commitment_transaction(self.context.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, logger);
let counterparty_commitment_txid = commitment_stats.tx.trust().txid();
#[cfg(any(test, fuzzing))]
{
- if !self.is_outbound() {
+ if !self.context.is_outbound() {
let projected_commit_tx_info = self.context.next_remote_commitment_tx_fee_info_cached.lock().unwrap().take();
*self.context.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
if let Some(info) = projected_commit_tx_info {
&& info.next_holder_htlc_id == self.context.next_holder_htlc_id
&& info.next_counterparty_htlc_id == self.context.next_counterparty_htlc_id
&& info.feerate == self.context.feerate_per_kw {
- let actual_fee = Self::commit_tx_fee_msat(self.context.feerate_per_kw, commitment_stats.num_nondust_htlcs, self.context.opt_anchors());
+ let actual_fee = commit_tx_fee_msat(self.context.feerate_per_kw, commitment_stats.num_nondust_htlcs, self.context.opt_anchors());
assert_eq!(actual_fee, info.fee);
}
}
#[cfg(any(test, fuzzing))]
self.build_commitment_no_state_update(logger);
- let counterparty_keys = self.build_remote_transaction_keys();
- let commitment_stats = self.build_commitment_transaction(self.context.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, logger);
+ let counterparty_keys = self.context.build_remote_transaction_keys();
+ let commitment_stats = self.context.build_commitment_transaction(self.context.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, logger);
let counterparty_commitment_txid = commitment_stats.tx.trust().txid();
let (signature, htlc_signatures);
log_trace!(logger, "Signed remote commitment tx {} (txid {}) with redeemscript {} -> {} in channel {}",
encode::serialize_hex(&commitment_stats.tx.trust().built_transaction().transaction),
- &counterparty_commitment_txid, encode::serialize_hex(&self.get_funding_redeemscript()),
- log_bytes!(signature.serialize_compact()[..]), log_bytes!(self.channel_id()));
+ &counterparty_commitment_txid, encode::serialize_hex(&self.context.get_funding_redeemscript()),
+ log_bytes!(signature.serialize_compact()[..]), log_bytes!(self.context.channel_id()));
for (ref htlc_sig, ref htlc) in htlc_signatures.iter().zip(htlcs) {
log_trace!(logger, "Signed remote HTLC tx {} with redeemscript {} with pubkey {} -> {} in channel {}",
- encode::serialize_hex(&chan_utils::build_htlc_transaction(&counterparty_commitment_txid, commitment_stats.feerate_per_kw, self.get_holder_selected_contest_delay(), htlc, self.context.opt_anchors(), false, &counterparty_keys.broadcaster_delayed_payment_key, &counterparty_keys.revocation_key)),
+ encode::serialize_hex(&chan_utils::build_htlc_transaction(&counterparty_commitment_txid, commitment_stats.feerate_per_kw, self.context.get_holder_selected_contest_delay(), htlc, self.context.opt_anchors(), false, &counterparty_keys.broadcaster_delayed_payment_key, &counterparty_keys.revocation_key)),
encode::serialize_hex(&chan_utils::get_htlc_redeemscript(&htlc, self.context.opt_anchors(), &counterparty_keys)),
log_bytes!(counterparty_keys.broadcaster_htlc_key.serialize()),
- log_bytes!(htlc_sig.serialize_compact()[..]), log_bytes!(self.channel_id()));
+ log_bytes!(htlc_sig.serialize_compact()[..]), log_bytes!(self.context.channel_id()));
}
}
}
}
- /// Get forwarding information for the counterparty.
- pub fn counterparty_forwarding_info(&self) -> Option<CounterpartyForwardingInfo> {
- self.context.counterparty_forwarding_info.clone()
- }
-
pub fn channel_update(&mut self, msg: &msgs::ChannelUpdate) -> Result<(), ChannelError> {
if msg.contents.htlc_minimum_msat >= self.context.channel_value_satoshis * 1000 {
return Err(ChannelError::Close("Minimum htlc value is greater than channel value".to_string()));
// We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
// return them to fail the payment.
let mut dropped_outbound_htlcs = Vec::with_capacity(self.context.holding_cell_htlc_updates.len());
- let counterparty_node_id = self.get_counterparty_node_id();
+ let counterparty_node_id = self.context.get_counterparty_node_id();
for htlc_update in self.context.holding_cell_htlc_updates.drain(..) {
match htlc_update {
HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
_ => {}
}
}
- let monitor_update = if let Some(funding_txo) = self.get_funding_txo() {
+ let monitor_update = if let Some(funding_txo) = self.context.get_funding_txo() {
// If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
// returning a channel monitor update here would imply a channel monitor update before
// we even registered the channel monitor to begin with, which is invalid.
// See test_duplicate_chan_id and test_pre_lockin_no_chan_closed_update for more.
if self.context.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelReady as u32 | ChannelState::ShutdownComplete as u32) != 0 {
self.context.latest_monitor_update_id = CLOSED_CHANNEL_UPDATE_ID;
- Some((self.get_counterparty_node_id(), funding_txo, ChannelMonitorUpdate {
+ Some((self.context.get_counterparty_node_id(), funding_txo, ChannelMonitorUpdate {
update_id: self.context.latest_monitor_update_id,
updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
}))
fail_reason.write(writer)?;
}
- if self.is_outbound() {
+ if self.context.is_outbound() {
self.context.pending_update_fee.map(|(a, _)| a).write(writer)?;
} else if let Some((feerate, FeeUpdateState::AwaitingRemoteRevokeToAnnounce)) = self.context.pending_update_fee {
Some(feerate).write(writer)?;
use crate::ln::channelmanager::{self, HTLCSource, PaymentId};
#[cfg(anchors)]
use crate::ln::channel::InitFeatures;
- use crate::ln::channel::{Channel, InboundHTLCOutput, OutboundHTLCOutput, InboundHTLCState, OutboundHTLCState, HTLCCandidate, HTLCInitiator};
+ use crate::ln::channel::{Channel, InboundHTLCOutput, OutboundHTLCOutput, InboundHTLCState, OutboundHTLCState, HTLCCandidate, HTLCInitiator, commit_tx_fee_msat};
use crate::ln::channel::{MAX_FUNDING_SATOSHIS_NO_WUMBO, TOTAL_BITCOIN_SUPPLY_SATOSHIS, MIN_THEIR_CHAN_RESERVE_SATOSHIS};
use crate::ln::features::ChannelTypeFeatures;
use crate::ln::msgs::{ChannelUpdate, DecodeError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
// Make sure when Node A calculates their local commitment transaction, none of the HTLCs pass
// the dust limit check.
let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
- let local_commit_tx_fee = node_a_chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
- let local_commit_fee_0_htlcs = Channel::<EnforcingSigner>::commit_tx_fee_msat(node_a_chan.context.feerate_per_kw, 0, node_a_chan.context.opt_anchors());
+ let local_commit_tx_fee = node_a_chan.context.next_local_commit_tx_fee_msat(htlc_candidate, None);
+ let local_commit_fee_0_htlcs = commit_tx_fee_msat(node_a_chan.context.feerate_per_kw, 0, node_a_chan.context.opt_anchors());
assert_eq!(local_commit_tx_fee, local_commit_fee_0_htlcs);
// Finally, make sure that when Node A calculates the remote's commitment transaction fees, all
// of the HTLCs are seen to be above the dust limit.
node_a_chan.context.channel_transaction_parameters.is_outbound_from_holder = false;
- let remote_commit_fee_3_htlcs = Channel::<EnforcingSigner>::commit_tx_fee_msat(node_a_chan.context.feerate_per_kw, 3, node_a_chan.context.opt_anchors());
+ let remote_commit_fee_3_htlcs = commit_tx_fee_msat(node_a_chan.context.feerate_per_kw, 3, node_a_chan.context.opt_anchors());
let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
- let remote_commit_tx_fee = node_a_chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
+ let remote_commit_tx_fee = node_a_chan.context.next_remote_commit_tx_fee_msat(htlc_candidate, None);
assert_eq!(remote_commit_tx_fee, remote_commit_fee_3_htlcs);
}
let config = UserConfig::default();
let mut chan = Channel::<EnforcingSigner>::new_outbound(&fee_est, &&keys_provider, &&keys_provider, node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
- let commitment_tx_fee_0_htlcs = Channel::<EnforcingSigner>::commit_tx_fee_msat(chan.context.feerate_per_kw, 0, chan.context.opt_anchors());
- let commitment_tx_fee_1_htlc = Channel::<EnforcingSigner>::commit_tx_fee_msat(chan.context.feerate_per_kw, 1, chan.context.opt_anchors());
+ let commitment_tx_fee_0_htlcs = commit_tx_fee_msat(chan.context.feerate_per_kw, 0, chan.context.opt_anchors());
+ let commitment_tx_fee_1_htlc = commit_tx_fee_msat(chan.context.feerate_per_kw, 1, chan.context.opt_anchors());
// If HTLC_SUCCESS_TX_WEIGHT and HTLC_TIMEOUT_TX_WEIGHT were swapped: then this HTLC would be
// counted as dust when it shouldn't be.
let htlc_amt_above_timeout = ((253 * htlc_timeout_tx_weight(chan.context.opt_anchors()) / 1000) + chan.context.holder_dust_limit_satoshis + 1) * 1000;
let htlc_candidate = HTLCCandidate::new(htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
- let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
+ let commitment_tx_fee = chan.context.next_local_commit_tx_fee_msat(htlc_candidate, None);
assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
// If swapped: this HTLC would be counted as non-dust when it shouldn't be.
let dust_htlc_amt_below_success = ((253 * htlc_success_tx_weight(chan.context.opt_anchors()) / 1000) + chan.context.holder_dust_limit_satoshis - 1) * 1000;
let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_below_success, HTLCInitiator::RemoteOffered);
- let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
+ let commitment_tx_fee = chan.context.next_local_commit_tx_fee_msat(htlc_candidate, None);
assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
chan.context.channel_transaction_parameters.is_outbound_from_holder = false;
// If swapped: this HTLC would be counted as non-dust when it shouldn't be.
let dust_htlc_amt_above_timeout = ((253 * htlc_timeout_tx_weight(chan.context.opt_anchors()) / 1000) + chan.context.counterparty_dust_limit_satoshis + 1) * 1000;
let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
- let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
+ let commitment_tx_fee = chan.context.next_remote_commit_tx_fee_msat(htlc_candidate, None);
assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
// If swapped: this HTLC would be counted as dust when it shouldn't be.
let htlc_amt_below_success = ((253 * htlc_success_tx_weight(chan.context.opt_anchors()) / 1000) + chan.context.counterparty_dust_limit_satoshis - 1) * 1000;
let htlc_candidate = HTLCCandidate::new(htlc_amt_below_success, HTLCInitiator::RemoteOffered);
- let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
+ let commitment_tx_fee = chan.context.next_remote_commit_tx_fee_msat(htlc_candidate, None);
assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
}
node_a_chan.accept_channel(&accept_channel_msg, &config.channel_handshake_limits, &channelmanager::provided_init_features(&config)).unwrap();
// Node A --> Node B: funding created
- let output_script = node_a_chan.get_funding_redeemscript();
+ let output_script = node_a_chan.context.get_funding_redeemscript();
let tx = Transaction { version: 1, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: vec![TxOut {
value: 10000000, script_pubkey: output_script.clone(),
}]};
let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
assert!(node_a_chan.context.counterparty_forwarding_info.is_none());
assert_eq!(node_a_chan.context.holder_htlc_minimum_msat, 1); // the default
- assert!(node_a_chan.counterparty_forwarding_info().is_none());
+ assert!(node_a_chan.context.counterparty_forwarding_info().is_none());
// Make sure that receiving a channel update will update the Channel as expected.
let update = ChannelUpdate {
// The counterparty can send an update with a higher minimum HTLC, but that shouldn't
// change our official htlc_minimum_msat.
assert_eq!(node_a_chan.context.holder_htlc_minimum_msat, 1);
- match node_a_chan.counterparty_forwarding_info() {
+ match node_a_chan.context.counterparty_forwarding_info() {
Some(info) => {
assert_eq!(info.cltv_expiry_delta, 100);
assert_eq!(info.fee_base_msat, 110);
$( { $htlc_idx: expr, $counterparty_htlc_sig_hex: expr, $htlc_sig_hex: expr, $htlc_tx_hex: expr } ), *
} ) => { {
let (commitment_tx, htlcs): (_, Vec<HTLCOutputInCommitment>) = {
- let mut commitment_stats = chan.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, &logger);
+ let mut commitment_stats = chan.context.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, &logger);
let htlcs = commitment_stats.htlcs_included.drain(..)
.filter_map(|(htlc, _)| if htlc.transaction_output_index.is_some() { Some(htlc) } else { None })
};
let trusted_tx = commitment_tx.trust();
let unsigned_tx = trusted_tx.built_transaction();
- let redeemscript = chan.get_funding_redeemscript();
+ let redeemscript = chan.context.get_funding_redeemscript();
let counterparty_signature = Signature::from_der(&hex::decode($counterparty_sig_hex).unwrap()[..]).unwrap();
let sighash = unsigned_tx.get_sighash_all(&redeemscript, chan.context.channel_value_satoshis);
log_trace!(logger, "unsigned_tx = {}", hex::encode(serialize(&unsigned_tx.transaction)));
- assert!(secp_ctx.verify_ecdsa(&sighash, &counterparty_signature, chan.counterparty_funding_pubkey()).is_ok(), "verify counterparty commitment sig");
+ assert!(secp_ctx.verify_ecdsa(&sighash, &counterparty_signature, chan.context.counterparty_funding_pubkey()).is_ok(), "verify counterparty commitment sig");
let mut per_htlc: Vec<(HTLCOutputInCommitment, Option<Signature>)> = Vec::new();
per_htlc.clear(); // Don't warn about excess mut for no-HTLC calls
counterparty_signature,
counterparty_htlc_sigs,
&chan.context.holder_signer.pubkeys().funding_pubkey,
- chan.counterparty_funding_pubkey()
+ chan.context.counterparty_funding_pubkey()
);
let (holder_sig, htlc_sigs) = signer.sign_holder_commitment_and_htlcs(&holder_commitment_tx, &secp_ctx).unwrap();
assert_eq!(Signature::from_der(&hex::decode($sig_hex).unwrap()[..]).unwrap(), holder_sig, "holder_sig");
- let funding_redeemscript = chan.get_funding_redeemscript();
+ let funding_redeemscript = chan.context.get_funding_redeemscript();
let tx = holder_commitment_tx.add_holder_sig(&funding_redeemscript, holder_sig);
assert_eq!(serialize(&tx)[..], hex::decode($tx_hex).unwrap()[..], "tx");
let ref htlc = htlcs[$htlc_idx];
let htlc_tx = chan_utils::build_htlc_transaction(&unsigned_tx.txid, chan.context.feerate_per_kw,
- chan.get_counterparty_selected_contest_delay().unwrap(),
+ chan.context.get_counterparty_selected_contest_delay().unwrap(),
&htlc, $opt_anchors, false, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, $opt_anchors, &keys);
let htlc_sighashtype = if $opt_anchors { EcdsaSighashType::SinglePlusAnyoneCanPay } else { EcdsaSighashType::All };