Make channel reserve variable names less confusing.
authorValentine Wallace <vwallace@protonmail.com>
Fri, 1 May 2020 22:39:18 +0000 (18:39 -0400)
committerValentine Wallace <vwallace@protonmail.com>
Fri, 1 May 2020 23:35:44 +0000 (19:35 -0400)
Previous to this commit, variables such as their_channel_reserve
referred to the channel reserve that _we_ are required to keep,
(the value is initially set by the remote). Similarly,
variables such as our_channel_reserve referred to the channel
reserve that we require the remote to keep.

Change this to use local_channel_reserve / remote_channel_reserve
to refer to the the channel reserve that the local is required to keep
and the channel reserve that the remote is required to keep, respectively.

lightning/src/ln/channel.rs
lightning/src/ln/functional_tests.rs

index 469698356af3dcdad9c1e9d50cffc4aad98f78d8..99dfae389d3d9543e6b12b7e035a896273eb4067 100644 (file)
@@ -329,9 +329,9 @@ pub(super) struct Channel<ChanSigner: ChannelKeys> {
        #[cfg(not(test))]
        their_max_htlc_value_in_flight_msat: u64,
        //get_our_max_htlc_value_in_flight_msat(): u64,
-       /// minimum channel reserve for **self** to maintain - set by them.
-       their_channel_reserve_satoshis: u64,
-       //get_our_channel_reserve_satoshis(): u64,
+       /// minimum channel reserve for self to maintain - set by them.
+       local_channel_reserve_satoshis: u64,
+       // get_remote_channel_reserve_satoshis(channel_value_sats: u64): u64
        their_htlc_minimum_msat: u64,
        our_htlc_minimum_msat: u64,
        their_to_self_delay: u16,
@@ -420,10 +420,11 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                channel_value_satoshis * 1000 / 10 //TODO
        }
 
-       /// Returns a minimum channel reserve value **they** need to maintain
+       /// Returns a minimum channel reserve value the remote needs to maintain,
+       /// required by us.
        ///
        /// Guaranteed to return a value no larger than channel_value_satoshis
-       pub(crate) fn get_our_channel_reserve_satoshis(channel_value_satoshis: u64) -> u64 {
+       pub(crate) fn get_remote_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)) //TODO
        }
@@ -452,7 +453,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
 
                let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
-               if Channel::<ChanSigner>::get_our_channel_reserve_satoshis(channel_value_satoshis) < Channel::<ChanSigner>::derive_our_dust_limit_satoshis(background_feerate) {
+               if Channel::<ChanSigner>::get_remote_channel_reserve_satoshis(channel_value_satoshis) < Channel::<ChanSigner>::derive_our_dust_limit_satoshis(background_feerate) {
                        return Err(APIError::FeeRateTooHigh{err: format!("Not enough reserve above dust limit can be found at current fee rate({})", background_feerate), feerate: background_feerate});
                }
 
@@ -512,7 +513,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                        their_dust_limit_satoshis: 0,
                        our_dust_limit_satoshis: Channel::<ChanSigner>::derive_our_dust_limit_satoshis(background_feerate),
                        their_max_htlc_value_in_flight_msat: 0,
-                       their_channel_reserve_satoshis: 0,
+                       local_channel_reserve_satoshis: 0,
                        their_htlc_minimum_msat: 0,
                        our_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
                        their_to_self_delay: 0,
@@ -638,15 +639,15 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
 
                let our_dust_limit_satoshis = Channel::<ChanSigner>::derive_our_dust_limit_satoshis(background_feerate);
-               let our_channel_reserve_satoshis = Channel::<ChanSigner>::get_our_channel_reserve_satoshis(msg.funding_satoshis);
-               if our_channel_reserve_satoshis < our_dust_limit_satoshis {
+               let remote_channel_reserve_satoshis = Channel::<ChanSigner>::get_remote_channel_reserve_satoshis(msg.funding_satoshis);
+               if remote_channel_reserve_satoshis < our_dust_limit_satoshis {
                        return Err(ChannelError::Close("Suitable channel reserve not found. aborting"));
                }
                if msg.channel_reserve_satoshis < our_dust_limit_satoshis {
                        return Err(ChannelError::Close("channel_reserve_satoshis too small"));
                }
-               if our_channel_reserve_satoshis < msg.dust_limit_satoshis {
-                       return Err(ChannelError::Close("Dust limit too high for our channel reserve"));
+               if remote_channel_reserve_satoshis < msg.dust_limit_satoshis {
+                       return Err(ChannelError::Close("Dust limit too high for the channel reserve we require the remote to keep"));
                }
 
                // check if the funder's amount for the initial commitment tx is sufficient
@@ -658,7 +659,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
                let to_local_msat = msg.push_msat;
                let to_remote_msat = funders_amount_msat - background_feerate * COMMITMENT_TX_BASE_WEIGHT;
-               if to_local_msat <= msg.channel_reserve_satoshis * 1000 && to_remote_msat <= our_channel_reserve_satoshis * 1000 {
+               if to_local_msat <= msg.channel_reserve_satoshis * 1000 && to_remote_msat <= remote_channel_reserve_satoshis * 1000 {
                        return Err(ChannelError::Close("Insufficient funding amount for initial commitment"));
                }
 
@@ -737,7 +738,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                        their_dust_limit_satoshis: msg.dust_limit_satoshis,
                        our_dust_limit_satoshis: our_dust_limit_satoshis,
                        their_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
-                       their_channel_reserve_satoshis: msg.channel_reserve_satoshis,
+                       local_channel_reserve_satoshis: msg.channel_reserve_satoshis,
                        their_htlc_minimum_msat: msg.htlc_minimum_msat,
                        our_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
                        their_to_self_delay: msg.to_self_delay,
@@ -952,9 +953,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                        } else {
                                self.max_commitment_tx_output_remote.lock().unwrap()
                        };
-                       debug_assert!(max_commitment_tx_output.0 <= value_to_self_msat as u64 || value_to_self_msat / 1000 >= self.their_channel_reserve_satoshis as i64);
+                       debug_assert!(max_commitment_tx_output.0 <= value_to_self_msat as u64 || value_to_self_msat / 1000 >= self.local_channel_reserve_satoshis as i64);
                        max_commitment_tx_output.0 = cmp::max(max_commitment_tx_output.0, value_to_self_msat as u64);
-                       debug_assert!(max_commitment_tx_output.1 <= value_to_remote_msat as u64 || value_to_remote_msat / 1000 >= Channel::<ChanSigner>::get_our_channel_reserve_satoshis(self.channel_value_satoshis) as i64);
+                       debug_assert!(max_commitment_tx_output.1 <= value_to_remote_msat as u64 || value_to_remote_msat / 1000 >= Channel::<ChanSigner>::get_remote_channel_reserve_satoshis(self.channel_value_satoshis) as i64);
                        max_commitment_tx_output.1 = cmp::max(max_commitment_tx_output.1, value_to_remote_msat as u64);
                }
 
@@ -1362,7 +1363,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                if msg.channel_reserve_satoshis < self.our_dust_limit_satoshis {
                        return Err(ChannelError::Close("Peer never wants payout outputs?"));
                }
-               if msg.dust_limit_satoshis > Channel::<ChanSigner>::get_our_channel_reserve_satoshis(self.channel_value_satoshis) {
+               if msg.dust_limit_satoshis > Channel::<ChanSigner>::get_remote_channel_reserve_satoshis(self.channel_value_satoshis) {
                        return Err(ChannelError::Close("Dust limit is bigger than our channel reverse"));
                }
                if msg.htlc_minimum_msat >= (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000 {
@@ -1424,7 +1425,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
                self.their_dust_limit_satoshis = msg.dust_limit_satoshis;
                self.their_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000);
-               self.their_channel_reserve_satoshis = msg.channel_reserve_satoshis;
+               self.local_channel_reserve_satoshis = msg.channel_reserve_satoshis;
                self.their_htlc_minimum_msat = msg.htlc_minimum_msat;
                self.their_to_self_delay = msg.to_self_delay;
                self.their_max_accepted_htlcs = msg.max_accepted_htlcs;
@@ -1696,7 +1697,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                if htlc_inbound_value_msat + msg.amount_msat > Channel::<ChanSigner>::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis) {
                        return Err(ChannelError::Close("Remote HTLC add would put them over our max HTLC value"));
                }
-               // Check our_channel_reserve_satoshis (we're getting paid, so they have to at least meet
+               // Check remote_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).
                // Note that we don't really care about having a small/no to_remote output in our local
@@ -1716,8 +1717,8 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                                removed_outbound_total_msat += htlc.amount_msat;
                        }
                }
-               if htlc_inbound_value_msat + msg.amount_msat + self.value_to_self_msat > (self.channel_value_satoshis - Channel::<ChanSigner>::get_our_channel_reserve_satoshis(self.channel_value_satoshis)) * 1000 + removed_outbound_total_msat {
-                       return Err(ChannelError::Close("Remote HTLC add would put them over their reserve value"));
+               if htlc_inbound_value_msat + msg.amount_msat + self.value_to_self_msat > (self.channel_value_satoshis - Channel::<ChanSigner>::get_remote_channel_reserve_satoshis(self.channel_value_satoshis)) * 1000 + removed_outbound_total_msat {
+                       return Err(ChannelError::Close("Remote HTLC add would put them under their reserve value"));
                }
                if self.next_remote_htlc_id != msg.htlc_id {
                        return Err(ChannelError::Close("Remote skipped HTLC ID"));
@@ -1847,7 +1848,8 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                        let num_htlcs = local_commitment_tx.1;
                        let total_fee: u64 = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
 
-                       if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + self.their_channel_reserve_satoshis {
+                       let remote_reserve_we_require = Channel::<ChanSigner>::get_remote_channel_reserve_satoshis(self.channel_value_satoshis);
+                       if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + remote_reserve_we_require {
                                return Err((None, ChannelError::Close("Funding remote cannot afford proposed new fee")));
                        }
                }
@@ -3033,7 +3035,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                ChannelValueStat {
                        value_to_self_msat: self.value_to_self_msat,
                        channel_value_msat: self.channel_value_satoshis * 1000,
-                       channel_reserve_msat: self.their_channel_reserve_satoshis * 1000,
+                       channel_reserve_msat: self.local_channel_reserve_satoshis * 1000,
                        pending_outbound_htlcs_amount_msat: self.pending_outbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
                        pending_inbound_htlcs_amount_msat: self.pending_inbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
                        holding_cell_outbound_amount_msat: {
@@ -3321,7 +3323,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                        push_msat: self.channel_value_satoshis * 1000 - self.value_to_self_msat,
                        dust_limit_satoshis: self.our_dust_limit_satoshis,
                        max_htlc_value_in_flight_msat: Channel::<ChanSigner>::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
-                       channel_reserve_satoshis: Channel::<ChanSigner>::get_our_channel_reserve_satoshis(self.channel_value_satoshis),
+                       channel_reserve_satoshis: Channel::<ChanSigner>::get_remote_channel_reserve_satoshis(self.channel_value_satoshis),
                        htlc_minimum_msat: self.our_htlc_minimum_msat,
                        feerate_per_kw: fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background) as u32,
                        to_self_delay: self.our_to_self_delay,
@@ -3354,7 +3356,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                        temporary_channel_id: self.channel_id,
                        dust_limit_satoshis: self.our_dust_limit_satoshis,
                        max_htlc_value_in_flight_msat: Channel::<ChanSigner>::get_our_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
-                       channel_reserve_satoshis: Channel::<ChanSigner>::get_our_channel_reserve_satoshis(self.channel_value_satoshis),
+                       channel_reserve_satoshis: Channel::<ChanSigner>::get_remote_channel_reserve_satoshis(self.channel_value_satoshis),
                        htlc_minimum_msat: self.our_htlc_minimum_msat,
                        minimum_depth: self.minimum_depth,
                        to_self_delay: self.our_to_self_delay,
@@ -3550,10 +3552,10 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                        return Err(ChannelError::Ignore("Cannot send value that would put us over the max HTLC value in flight our peer will accept"));
                }
 
-               // Check self.their_channel_reserve_satoshis (the amount we must keep as
-               // reserve for them to have something to claim if we misbehave)
-               if self.value_to_self_msat < self.their_channel_reserve_satoshis * 1000 + amount_msat + htlc_outbound_value_msat {
-                       return Err(ChannelError::Ignore("Cannot send value that would put us over their reserve value"));
+               // Check self.local_channel_reserve_satoshis (the amount we must keep as
+               // reserve for the remote to have something to claim if we misbehave)
+               if self.value_to_self_msat < self.local_channel_reserve_satoshis * 1000 + amount_msat + htlc_outbound_value_msat {
+                       return Err(ChannelError::Ignore("Cannot send value that would put us under local channel reserve value"));
                }
 
                // Now update local state:
@@ -4019,7 +4021,7 @@ impl<ChanSigner: ChannelKeys + Writeable> Writeable for Channel<ChanSigner> {
                self.their_dust_limit_satoshis.write(writer)?;
                self.our_dust_limit_satoshis.write(writer)?;
                self.their_max_htlc_value_in_flight_msat.write(writer)?;
-               self.their_channel_reserve_satoshis.write(writer)?;
+               self.local_channel_reserve_satoshis.write(writer)?;
                self.their_htlc_minimum_msat.write(writer)?;
                self.our_htlc_minimum_msat.write(writer)?;
                self.their_to_self_delay.write(writer)?;
@@ -4175,7 +4177,7 @@ impl<ChanSigner: ChannelKeys + Readable> ReadableArgs<Arc<Logger>> for Channel<C
                let their_dust_limit_satoshis = Readable::read(reader)?;
                let our_dust_limit_satoshis = Readable::read(reader)?;
                let their_max_htlc_value_in_flight_msat = Readable::read(reader)?;
-               let their_channel_reserve_satoshis = Readable::read(reader)?;
+               let local_channel_reserve_satoshis = Readable::read(reader)?;
                let their_htlc_minimum_msat = Readable::read(reader)?;
                let our_htlc_minimum_msat = Readable::read(reader)?;
                let their_to_self_delay = Readable::read(reader)?;
@@ -4254,7 +4256,7 @@ impl<ChanSigner: ChannelKeys + Readable> ReadableArgs<Arc<Logger>> for Channel<C
                        their_dust_limit_satoshis,
                        our_dust_limit_satoshis,
                        their_max_htlc_value_in_flight_msat,
-                       their_channel_reserve_satoshis,
+                       local_channel_reserve_satoshis,
                        their_htlc_minimum_msat,
                        our_htlc_minimum_msat,
                        their_to_self_delay,
index cfc29394f8b5e56acce9454b2b5d096b5af0e109..d67a2adb0828841b6dabf149f38575229ae28166 100644 (file)
@@ -64,7 +64,7 @@ fn test_insane_channel_opens() {
        // Instantiate channel parameters where we push the maximum msats given our
        // funding satoshis
        let channel_value_sat = 31337; // same as funding satoshis
-       let channel_reserve_satoshis = Channel::<EnforcingChannelKeys>::get_our_channel_reserve_satoshis(channel_value_sat);
+       let channel_reserve_satoshis = Channel::<EnforcingChannelKeys>::get_remote_channel_reserve_satoshis(channel_value_sat);
        let push_msat = (channel_value_sat - channel_reserve_satoshis) * 1000;
 
        // Have node0 initiate a channel to node1 with aforementioned parameters
@@ -1578,9 +1578,9 @@ fn do_channel_reserve_test(test_recv: bool) {
                // attempt to get channel_reserve violation
                let (route, our_payment_hash, _) = get_route_and_payment_hash!(recv_value + 1);
                unwrap_send_err!(nodes[0].node.send_payment(&route, our_payment_hash, &None), true, APIError::ChannelUnavailable { err },
-                       assert_eq!(err, "Cannot send value that would put us over their reserve value"));
+                       assert_eq!(err, "Cannot send value that would put us under local channel reserve value"));
                assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
-               nodes[0].logger.assert_log("lightning::ln::channelmanager".to_string(), "Cannot send value that would put us over their reserve value".to_string(), 1);
+               nodes[0].logger.assert_log("lightning::ln::channelmanager".to_string(), "Cannot send value that would put us under local channel reserve value".to_string(), 1);
        }
 
        // adding pending output
@@ -1603,9 +1603,9 @@ fn do_channel_reserve_test(test_recv: bool) {
        {
                let (route, our_payment_hash, _) = get_route_and_payment_hash!(recv_value_2 + 1);
                unwrap_send_err!(nodes[0].node.send_payment(&route, our_payment_hash, &None), true, APIError::ChannelUnavailable { err },
-                       assert_eq!(err, "Cannot send value that would put us over their reserve value"));
+                       assert_eq!(err, "Cannot send value that would put us under local channel reserve value"));
                assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
-               nodes[0].logger.assert_log("lightning::ln::channelmanager".to_string(), "Cannot send value that would put us over their reserve value".to_string(), 2);
+               nodes[0].logger.assert_log("lightning::ln::channelmanager".to_string(), "Cannot send value that would put us under local channel reserve value".to_string(), 2);
        }
 
        {
@@ -1640,7 +1640,7 @@ fn do_channel_reserve_test(test_recv: bool) {
                        assert_eq!(nodes[1].node.list_channels().len(), 1);
                        assert_eq!(nodes[1].node.list_channels().len(), 1);
                        let err_msg = check_closed_broadcast!(nodes[1], true).unwrap();
-                       assert_eq!(err_msg.data, "Remote HTLC add would put them over their reserve value");
+                       assert_eq!(err_msg.data, "Remote HTLC add would put them under their reserve value");
                        check_added_monitors!(nodes[1], 1);
                        return;
                }
@@ -1666,9 +1666,9 @@ fn do_channel_reserve_test(test_recv: bool) {
        {
                let (route, our_payment_hash, _) = get_route_and_payment_hash!(recv_value_22+1);
                unwrap_send_err!(nodes[0].node.send_payment(&route, our_payment_hash, &None), true, APIError::ChannelUnavailable { err },
-                       assert_eq!(err, "Cannot send value that would put us over their reserve value"));
+                       assert_eq!(err, "Cannot send value that would put us under local channel reserve value"));
                assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
-               nodes[0].logger.assert_log("lightning::ln::channelmanager".to_string(), "Cannot send value that would put us over their reserve value".to_string(), 3);
+               nodes[0].logger.assert_log("lightning::ln::channelmanager".to_string(), "Cannot send value that would put us under local channel reserve value".to_string(), 3);
        }
 
        let (route_22, our_payment_hash_22, our_payment_preimage_22) = get_route_and_payment_hash!(recv_value_22);
@@ -5977,7 +5977,7 @@ fn test_update_add_htlc_bolt2_receiver_sender_can_afford_amount_sent() {
 
        assert!(nodes[1].node.list_channels().is_empty());
        let err_msg = check_closed_broadcast!(nodes[1], true).unwrap();
-       assert_eq!(err_msg.data, "Remote HTLC add would put them over their reserve value");
+       assert_eq!(err_msg.data, "Remote HTLC add would put them under their reserve value");
        check_added_monitors!(nodes[1], 1);
 }