/// 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, will always return
- /// Ok(_) if debug assertions are turned on or preconditions are met.
- pub fn get_update_fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, logger: &L) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> where L::Target: Logger {
+ ///
+ /// 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?"))
+ }
+
+ /// 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.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");
}
return Ok(None);
}
- // Now update local state:
if (self.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.holding_cell_htlc_updates.iter() {
match pending_update {
&HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
} else { Ok((None, Vec::new())) }
}
- /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
- /// fulfilling or failing the last pending HTLC)
+ /// Frees any pending commitment updates in the holding cell, generating the relevant messages
+ /// for our counterparty.
fn free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
assert_eq!(self.channel_state & ChannelState::MonitorUpdateInProgress as u32, 0);
if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() {
// to rebalance channels.
match &htlc_update {
&HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => {
- match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone(), logger) {
+ match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone(), false, logger) {
Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()),
Err(e) => {
match e {
monitor_update.updates.append(&mut additional_monitor_update.updates);
},
&HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
- match self.get_update_fail_htlc(htlc_id, err_packet.clone(), logger) {
+ match self.fail_htlc(htlc_id, err_packet.clone(), false, logger) {
Ok(update_fail_msg_option) => {
// If an HTLC failure was previously added to the holding cell (via
- // `get_update_fail_htlc`) then generating the fail message itself
- // must not fail - we should never end up in a state where we
- // double-fail an HTLC or fail-then-claim an HTLC as it indicates
- // we didn't wait for a full revocation before failing.
+ // `queue_fail_htlc`) then generating the fail message itself must
+ // not fail - we should never end up in a state where we double-fail
+ // an HTLC or fail-then-claim an HTLC as it indicates we didn't wait
+ // for a full revocation before failing.
update_fail_htlcs.push(update_fail_msg_option.unwrap())
},
Err(e) => {
return Ok((None, htlcs_to_fail));
}
let update_fee = if let Some(feerate) = self.holding_cell_update_fee.take() {
- self.send_update_fee(feerate, logger)
+ self.send_update_fee(feerate, false, logger)
} else {
None
};
}
}
+ /// Queues up an outbound update fee by placing it in the holding cell. You should call
+ /// [`Self::maybe_free_holding_cell_htlcs`] in order to actually generate and send the
+ /// commitment update.
+ pub fn queue_update_fee<L: Deref>(&mut self, feerate_per_kw: u32, logger: &L) where L::Target: Logger {
+ let msg_opt = self.send_update_fee(feerate_per_kw, true, logger);
+ assert!(msg_opt.is_none(), "We forced holding cell?");
+ }
+
/// Adds a pending update to this channel. See the doc for send_htlc for
/// further details on the optionness of the return value.
/// If our balance is too low to cover the cost of the next commitment transaction at the
/// new feerate, the update is cancelled.
- /// You MUST call send_commitment prior to any other calls on this Channel
- fn send_update_fee<L: Deref>(&mut self, feerate_per_kw: u32, logger: &L) -> Option<msgs::UpdateFee> where L::Target: Logger {
+ ///
+ /// 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() {
panic!("Cannot send fee from inbound channel");
}
}
if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 {
+ force_holding_cell = true;
+ }
+
+ if force_holding_cell {
self.holding_cell_update_fee = Some(feerate_per_kw);
return None;
}
})
}
- pub fn send_update_fee_and_commit<L: Deref>(&mut self, feerate_per_kw: u32, logger: &L) -> Result<Option<(msgs::UpdateFee, msgs::CommitmentSigned, ChannelMonitorUpdate)>, ChannelError> where L::Target: Logger {
- match self.send_update_fee(feerate_per_kw, logger) {
- Some(update_fee) => {
- let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
- Ok(Some((update_fee, commitment_signed, monitor_update)))
- },
- None => Ok(None)
- }
- }
-
/// Removes any uncommitted inbound HTLCs and resets the state of uncommitted outbound HTLC
/// updates, to be used on peer disconnection. After this, update_*_htlc messages need to be
/// resent.
// Send stuff to our remote peers:
+ /// Queues up an outbound HTLC to send by placing it in the holding cell. You should call
+ /// [`Self::maybe_free_holding_cell_htlcs`] in order to actually generate and send the
+ /// commitment update.
+ ///
+ /// `Err`s will only be [`ChannelError::Ignore`].
+ pub fn queue_add_htlc<L: Deref>(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource,
+ onion_routing_packet: msgs::OnionPacket, logger: &L)
+ -> Result<(), ChannelError> where L::Target: Logger {
+ self
+ .send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet, true, logger)
+ .map(|msg_opt| assert!(msg_opt.is_none(), "We forced holding cell?"))
+ .map_err(|err| {
+ if let ChannelError::Ignore(_) = err { /* fine */ }
+ else { debug_assert!(false, "Queueing cannot trigger channel failure"); }
+ err
+ })
+ }
+
/// Adds a pending outbound HTLC to this channel, note that you probably want
- /// send_htlc_and_commit instead cause you'll want both messages at once.
+ /// [`Self::send_htlc_and_commit`] instead cause you'll want both messages at once.
///
/// This returns an optional UpdateAddHTLC as we may be in a state where we cannot add HTLCs on
/// the wire:
/// we may not yet have sent the previous commitment update messages and will need to
/// regenerate them.
///
- /// You MUST call send_commitment prior to calling any other methods on this Channel!
+ /// You MUST call [`Self::send_commitment_no_state_update`] prior to calling any other methods
+ /// on this [`Channel`] if `force_holding_cell` is false.
///
- /// If an Err is returned, it's a ChannelError::Ignore!
- pub fn send_htlc<L: Deref>(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket, logger: &L) -> Result<Option<msgs::UpdateAddHTLC>, ChannelError> where L::Target: Logger {
+ /// `Err`s will only be [`ChannelError::Ignore`].
+ fn send_htlc<L: Deref>(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource,
+ onion_routing_packet: msgs::OnionPacket, mut force_holding_cell: bool, logger: &L)
+ -> Result<Option<msgs::UpdateAddHTLC>, ChannelError> where L::Target: Logger {
if (self.channel_state & (ChannelState::ChannelReady as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelReady as u32) {
return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down".to_owned()));
}
return Err(ChannelError::Ignore(format!("Cannot send value that would put our balance under counterparty-announced channel reserve value ({})", chan_reserve_msat)));
}
- // Now update local state:
if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 {
+ force_holding_cell = true;
+ }
+
+ // Now update local state:
+ if force_holding_cell {
self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC {
amount_msat,
payment_hash,
Ok(Some(res))
}
- /// Creates a signed commitment transaction to send to the remote peer.
- /// Always returns a ChannelError::Close if an immediately-preceding (read: the
- /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
- /// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc.
- pub fn send_commitment<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
- if (self.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
- panic!("Cannot create commitment tx until channel is fully established");
- }
- if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
- panic!("Cannot create commitment tx until remote revokes their previous commitment");
- }
- if (self.channel_state & (ChannelState::PeerDisconnected as u32)) == (ChannelState::PeerDisconnected as u32) {
- panic!("Cannot create commitment tx while disconnected, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
- }
- if (self.channel_state & (ChannelState::MonitorUpdateInProgress as u32)) == (ChannelState::MonitorUpdateInProgress as u32) {
- panic!("Cannot create commitment tx while awaiting monitor update unfreeze, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
- }
- let mut have_updates = self.is_outbound() && self.pending_update_fee.is_some();
- for htlc in self.pending_outbound_htlcs.iter() {
- if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
- have_updates = true;
- }
- if have_updates { break; }
- }
- for htlc in self.pending_inbound_htlcs.iter() {
- if let InboundHTLCState::LocalRemoved(_) = htlc.state {
- have_updates = true;
- }
- if have_updates { break; }
- }
- if !have_updates {
- panic!("Cannot create commitment tx until we have some updates to send");
- }
- self.send_commitment_no_status_check(logger)
- }
/// Only fails in case of bad keys
fn send_commitment_no_status_check<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
log_trace!(logger, "Updating HTLC state for a newly-sent commitment_signed...");
/// Adds a pending outbound HTLC to this channel, and creates a signed commitment transaction
/// to send to the remote peer in one go.
- /// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
- /// more info.
+ ///
+ /// Shorthand for calling [`Self::send_htlc`] followed by a commitment update, see docs on
+ /// [`Self::send_htlc`] and [`Self::send_commitment_no_state_update`] for more info.
pub fn send_htlc_and_commit<L: Deref>(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket, logger: &L) -> Result<Option<(msgs::UpdateAddHTLC, msgs::CommitmentSigned, ChannelMonitorUpdate)>, ChannelError> where L::Target: Logger {
- match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet, logger)? {
+ match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet, false, logger)? {
Some(update_add_htlc) => {
let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
Ok(Some((update_add_htlc, commitment_signed, monitor_update)))
projects / rust-lightning / blobdiff