Increase our default/minimum dust limit to 354 sat/vbytes

[rust-lightning] / lightning / src / ln / channel.rs

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index a4bb10331467ca75bd7528d5aa3a84d2fded2568..582a7611dd9cecc57b784b6b186e5908196cba16 100644 (file)
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -565,11 +565,14 @@ pub const MAX_FUNDING_SATOSHIS: u64 = 1 << 24;
 /// upper bound to avoid negotiation conflicts with other implementations.
 pub const MAX_DUST_LIMIT_SATOSHIS: u64 = 2 * 330;
 
-/// A typical p2wsh output is 43 bytes to which Core's `GetDustThreshold()` sums up a minimal
-/// spend of 67 bytes (even if a p2wsh witnessScript might be *effectively* smaller), `dustRelayFee`
-/// is set to 3000sat/kb, thus 110 * 3000 / 1000 = 330. Per-protocol rules, all time-sensitive outputs
-/// are p2wsh, a value of 330 sats is the lower bound desired to ensure good propagation of transactions.
-pub const MIN_DUST_LIMIT_SATOSHIS: u64 = 330;
+/// 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/lightningnetwork/lightning-rfc/issues/905 for more details.
+pub const MIN_DUST_LIMIT_SATOSHIS: u64 = 354;
 
 /// 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
@@ -2165,7 +2168,7 @@ impl<Signer: Sign> Channel<Signer> {
                // We can't accept HTLCs sent after we've sent a shutdown.
                let local_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::LocalShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
                if local_sent_shutdown {
-                       pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|20);
+                       pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x4000|8);
                }
                // If the remote has sent a shutdown prior to adding this HTLC, then they are in violation of the spec.
                let remote_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
@@ -3047,13 +3050,10 @@ impl<Signer: Sign> Channel<Signer> {
        /// monitor update failure must *not* have been sent to the remote end, and must instead
        /// have been dropped. They will be regenerated when monitor_updating_restored is called.
        pub fn monitor_update_failed(&mut self, resend_raa: bool, resend_commitment: bool, mut pending_forwards: Vec<(PendingHTLCInfo, u64)>, mut pending_fails: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>) {
-               assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
-               self.monitor_pending_revoke_and_ack = resend_raa;
-               self.monitor_pending_commitment_signed = resend_commitment;
-               assert!(self.monitor_pending_forwards.is_empty());
-               mem::swap(&mut pending_forwards, &mut self.monitor_pending_forwards);
-               assert!(self.monitor_pending_failures.is_empty());
-               mem::swap(&mut pending_fails, &mut self.monitor_pending_failures);
+               self.monitor_pending_revoke_and_ack |= resend_raa;
+               self.monitor_pending_commitment_signed |= resend_commitment;
+               self.monitor_pending_forwards.append(&mut pending_forwards);
+               self.monitor_pending_failures.append(&mut pending_fails);
                self.channel_state |= ChannelState::MonitorUpdateFailed as u32;
        }