Add outbound min/max to `ChannelCounterparty`

diff --git a/fuzz/src/router.rs b/fuzz/src/router.rs
index 4db6587b45626171b54095d7d746246a755d1f76..b0f052dbc646f613a1d8c038c88c96c3604ef88e 100644 (file)
--- a/fuzz/src/router.rs
+++ b/fuzz/src/router.rs
@@ -213,6 +213,8 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                                                                        features: InitFeatures::known(),
                                                                        unspendable_punishment_reserve: 0,
                                                                        forwarding_info: None,
+                                                                       outbound_htlc_minimum_msat: None,
+                                                                       outbound_htlc_maximum_msat: None,
                                                                },
                                                                funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
                                                                channel_type: None,

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index 12fd6958348f07fed591be0eb79252ede1c30bb2..b0551bf8323f1617f7cba4c991c783221c778c46 100644 (file)
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -4347,6 +4347,11 @@ impl<Signer: Sign> Channel<Signer> {
                self.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.counterparty_max_htlc_value_in_flight_msat)
+       }
+
        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;

diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs
index abb20845c6c38290476fc33c189b2ab20e4a972e..020fc22cd1b79c4f684e047dff9355cd0825b41a 100644 (file)
--- a/lightning/src/ln/channelmanager.rs
+++ b/lightning/src/ln/channelmanager.rs
@@ -922,6 +922,12 @@ pub struct ChannelCounterparty {
        /// Information on the fees and requirements that the counterparty requires when forwarding
        /// payments to us through this channel.
        pub forwarding_info: Option<CounterpartyForwardingInfo>,
+       /// The smallest value HTLC (in msat) the remote peer will accept, for this channel. This field
+       /// is only `None` before we have received either the `OpenChannel` or `AcceptChannel` message
+       /// from the remote peer, or for `ChannelCounterparty` objects serialized prior to LDK 0.0.107.
+       pub outbound_htlc_minimum_msat: Option<u64>,
+       /// The largest value HTLC (in msat) the remote peer currently will accept, for this channel.
+       pub outbound_htlc_maximum_msat: Option<u64>,
 }
 
 /// Details of a channel, as returned by ChannelManager::list_channels and ChannelManager::list_usable_channels
@@ -1675,6 +1681,14 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                features: InitFeatures::empty(),
                                                unspendable_punishment_reserve: to_remote_reserve_satoshis,
                                                forwarding_info: channel.counterparty_forwarding_info(),
+                                               // Ensures that we have actually received the `htlc_minimum_msat` value
+                                               // from the counterparty through the `OpenChannel` or `AcceptChannel`
+                                               // message (as they are always the first message from the counterparty).
+                                               // Else `Channel::get_counterparty_htlc_minimum_msat` could return the
+                                               // default `0` value set by `Channel::new_outbound`.
+                                               outbound_htlc_minimum_msat: if channel.have_received_message() {
+                                                       Some(channel.get_counterparty_htlc_minimum_msat()) } else { None },
+                                               outbound_htlc_maximum_msat: channel.get_counterparty_htlc_maximum_msat(),
                                        },
                                        funding_txo: channel.get_funding_txo(),
                                        // Note that accept_channel (or open_channel) is always the first message, so
@@ -5904,6 +5918,8 @@ impl_writeable_tlv_based!(ChannelCounterparty, {
        (4, features, required),
        (6, unspendable_punishment_reserve, required),
        (8, forwarding_info, option),
+       (9, outbound_htlc_minimum_msat, option),
+       (11, outbound_htlc_maximum_msat, option),
 });
 
 impl_writeable_tlv_based!(ChannelDetails, {

diff --git a/lightning/src/routing/router.rs b/lightning/src/routing/router.rs
index 5afe052bb9a2ff10b1d2a59985fb248e91abdf1e..212ac2f10cae7d62695f032c6fd8ab0a4e523ffa 100644 (file)
--- a/lightning/src/routing/router.rs
+++ b/lightning/src/routing/router.rs
@@ -1735,6 +1735,8 @@ mod tests {
                                node_id,
                                unspendable_punishment_reserve: 0,
                                forwarding_info: None,
+                               outbound_htlc_minimum_msat: None,
+                               outbound_htlc_maximum_msat: None,
                        },
                        funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
                        channel_type: None,
@@ -5458,6 +5460,8 @@ mod benches {
                                node_id,
                                unspendable_punishment_reserve: 0,
                                forwarding_info: None,
+                               outbound_htlc_minimum_msat: None,
+                               outbound_htlc_maximum_msat: None,
                        },
                        funding_txo: Some(OutPoint {
                                txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0