Fix reserve check on HTLC receive/send

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

diff --git a/src/ln/channel.rs b/src/ln/channel.rs
index 59a5797bfd5e192d5e3c72ac81e5f82d7e59a96c..bf778815e275ac81042d94ee9831282ccfa4d21c 100644 (file)
--- a/src/ln/channel.rs
+++ b/src/ln/channel.rs
@@ -1012,8 +1012,10 @@ impl Channel {
                if htlc_inbound_value_msat + msg.amount_msat > Channel::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis) {
                        return Err(HandleError{err: "Remote HTLC add would put them over their max HTLC value in flight", msg: None});
                }
-               // Check our_channel_reserve_satoshis:
-               if htlc_inbound_value_msat + htlc_outbound_value_msat + msg.amount_msat > (self.channel_value_satoshis - Channel::get_our_channel_reserve_satoshis(self.channel_value_satoshis)) * 1000 {
+               // Check our_channel_reserve_satoshis (we're getting paid, so they have to at least meet
+               // the reserve_satoshis we told them to always have as direct payment so that they lose
+               // something if we punish them for broadcasting an old state).
+               if htlc_inbound_value_msat + htlc_outbound_value_msat + msg.amount_msat + self.value_to_self_msat > (self.channel_value_satoshis - Channel::get_our_channel_reserve_satoshis(self.channel_value_satoshis)) * 1000 {
                        return Err(HandleError{err: "Remote HTLC add would put them over their reserve value", msg: None});
                }
                if self.next_remote_htlc_id != msg.htlc_id {
@@ -1591,7 +1593,7 @@ impl Channel {
                        return Err(HandleError{err: "Cannot send value that would put us over our max HTLC value in flight", msg: None});
                }
                // Check their_channel_reserve_satoshis:
-               if htlc_outbound_value_msat + amount_msat > (self.channel_value_satoshis - self.their_channel_reserve_satoshis) * 1000 - htlc_inbound_value_msat {
+               if htlc_inbound_value_msat + htlc_outbound_value_msat + amount_msat + (self.channel_value_satoshis * 1000 - self.value_to_self_msat) > (self.channel_value_satoshis - self.their_channel_reserve_satoshis) * 1000 {
                        return Err(HandleError{err: "Cannot send value that would put us over our reserve value", msg: None});
                }