Improve ChannelDetails readability significantly.
[rust-lightning] / lightning / src / ln / channelmanager.rs
index dc3654927e98003ad0cdc38f01b16fdbc8a05cd4..e38b232e92d7089ec08c6184a130e052fe7c2c1c 100644 (file)
@@ -36,8 +36,7 @@ use bitcoin::secp256k1::ecdh::SharedSecret;
 use bitcoin::secp256k1;
 
 use chain;
-use chain::Confirm;
-use chain::Watch;
+use chain::{Confirm, Watch, BestBlock};
 use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
 use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, ChannelMonitorUpdateErr, HTLC_FAIL_BACK_BUFFER, CLTV_CLAIM_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS, ANTI_REORG_DELAY, MonitorEvent, CLOSED_CHANNEL_UPDATE_ID};
 use chain::transaction::{OutPoint, TransactionData};
@@ -508,34 +507,6 @@ pub struct ChainParameters {
        pub best_block: BestBlock,
 }
 
-/// The best known block as identified by its hash and height.
-#[derive(Clone, Copy, PartialEq)]
-pub struct BestBlock {
-       block_hash: BlockHash,
-       height: u32,
-}
-
-impl BestBlock {
-       /// Returns the best block from the genesis of the given network.
-       pub fn from_genesis(network: Network) -> Self {
-               BestBlock {
-                       block_hash: genesis_block(network).header.block_hash(),
-                       height: 0,
-               }
-       }
-
-       /// Returns the best block as identified by the given block hash and height.
-       pub fn new(block_hash: BlockHash, height: u32) -> Self {
-               BestBlock { block_hash, height }
-       }
-
-       /// Returns the best block hash.
-       pub fn block_hash(&self) -> BlockHash { self.block_hash }
-
-       /// Returns the best block height.
-       pub fn height(&self) -> u32 { self.height }
-}
-
 #[derive(Copy, Clone, PartialEq)]
 enum NotifyOption {
        DoPersist,
@@ -626,19 +597,44 @@ pub const MIN_FINAL_CLTV_EXPIRY: u32 = HTLC_FAIL_BACK_BUFFER + 3;
 const CHECK_CLTV_EXPIRY_SANITY: u32 = MIN_CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - CLTV_CLAIM_BUFFER - ANTI_REORG_DELAY - LATENCY_GRACE_PERIOD_BLOCKS;
 
 // Check for ability of an attacker to make us fail on-chain by delaying an HTLC claim. See
-// ChannelMontior::would_broadcast_at_height for a description of why this is needed.
+// ChannelMonitor::should_broadcast_holder_commitment_txn for a description of why this is needed.
 #[deny(const_err)]
 #[allow(dead_code)]
 const CHECK_CLTV_EXPIRY_SANITY_2: u32 = MIN_CLTV_EXPIRY_DELTA as u32 - LATENCY_GRACE_PERIOD_BLOCKS - 2*CLTV_CLAIM_BUFFER;
 
+/// Channel parameters which apply to our counterparty. These are split out from [`ChannelDetails`]
+/// to better separate parameters.
+#[derive(Clone, Debug, PartialEq)]
+pub struct ChannelCounterparty {
+       /// The node_id of our counterparty
+       pub node_id: PublicKey,
+       /// The Features the channel counterparty provided upon last connection.
+       /// Useful for routing as it is the most up-to-date copy of the counterparty's features and
+       /// many routing-relevant features are present in the init context.
+       pub features: InitFeatures,
+       /// The value, in satoshis, that must always be held in the channel for our counterparty. This
+       /// value ensures that if our counterparty broadcasts a revoked state, we can punish them by
+       /// claiming at least this value on chain.
+       ///
+       /// This value is not included in [`inbound_capacity_msat`] as it can never be spent.
+       ///
+       /// [`inbound_capacity_msat`]: ChannelDetails::inbound_capacity_msat
+       pub unspendable_punishment_reserve: u64,
+       /// Information on the fees and requirements that the counterparty requires when forwarding
+       /// payments to us through this channel.
+       pub forwarding_info: Option<CounterpartyForwardingInfo>,
+}
+
 /// Details of a channel, as returned by ChannelManager::list_channels and ChannelManager::list_usable_channels
-#[derive(Clone)]
+#[derive(Clone, Debug, PartialEq)]
 pub struct ChannelDetails {
        /// The channel's ID (prior to funding transaction generation, this is a random 32 bytes,
        /// thereafter this is the txid of the funding transaction xor the funding transaction output).
        /// Note that this means this value is *not* persistent - it can change once during the
        /// lifetime of the channel.
        pub channel_id: [u8; 32],
+       /// Parameters which apply to our counterparty. See individual fields for more information.
+       pub counterparty: ChannelCounterparty,
        /// The Channel's funding transaction output, if we've negotiated the funding transaction with
        /// our counterparty already.
        ///
@@ -648,45 +644,76 @@ pub struct ChannelDetails {
        /// The position of the funding transaction in the chain. None if the funding transaction has
        /// not yet been confirmed and the channel fully opened.
        pub short_channel_id: Option<u64>,
-       /// The node_id of our counterparty
-       pub remote_network_id: PublicKey,
-       /// The Features the channel counterparty provided upon last connection.
-       /// Useful for routing as it is the most up-to-date copy of the counterparty's features and
-       /// many routing-relevant features are present in the init context.
-       pub counterparty_features: InitFeatures,
        /// The value, in satoshis, of this channel as appears in the funding output
        pub channel_value_satoshis: u64,
+       /// The value, in satoshis, that must always be held in the channel for us. This value ensures
+       /// that if we broadcast a revoked state, our counterparty can punish us by claiming at least
+       /// this value on chain.
+       ///
+       /// This value is not included in [`outbound_capacity_msat`] as it can never be spent.
+       ///
+       /// This value will be `None` for outbound channels until the counterparty accepts the channel.
+       ///
+       /// [`outbound_capacity_msat`]: ChannelDetails::outbound_capacity_msat
+       pub unspendable_punishment_reserve: Option<u64>,
        /// The user_id passed in to create_channel, or 0 if the channel was inbound.
        pub user_id: u64,
        /// The available outbound capacity for sending HTLCs to the remote peer. This does not include
        /// any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
        /// available for inclusion in new outbound HTLCs). This further does not include any pending
        /// outgoing HTLCs which are awaiting some other resolution to be sent.
+       ///
+       /// This value is not exact. Due to various in-flight changes, feerate changes, and our
+       /// conflict-avoidance policy, exactly this amount is not likely to be spendable. However, we
+       /// should be able to spend nearly this amount.
        pub outbound_capacity_msat: u64,
        /// The available inbound capacity for the remote peer to send HTLCs to us. This does not
        /// include any pending HTLCs which are not yet fully resolved (and, thus, who's balance is not
        /// available for inclusion in new inbound HTLCs).
        /// Note that there are some corner cases not fully handled here, so the actual available
        /// inbound capacity may be slightly higher than this.
+       ///
+       /// This value is not exact. Due to various in-flight changes, feerate changes, and our
+       /// counterparty's conflict-avoidance policy, exactly this amount is not likely to be spendable.
+       /// However, our counterparty should be able to spend nearly this amount.
        pub inbound_capacity_msat: u64,
+       /// The number of required confirmations on the funding transaction before the funding will be
+       /// considered "locked". This number is selected by the channel fundee (i.e. us if
+       /// [`is_outbound`] is *not* set), and can be selected for inbound channels with
+       /// [`ChannelHandshakeConfig::minimum_depth`] or limited for outbound channels with
+       /// [`ChannelHandshakeLimits::max_minimum_depth`].
+       ///
+       /// This value will be `None` for outbound channels until the counterparty accepts the channel.
+       ///
+       /// [`is_outbound`]: ChannelDetails::is_outbound
+       /// [`ChannelHandshakeConfig::minimum_depth`]: crate::util::config::ChannelHandshakeConfig::minimum_depth
+       /// [`ChannelHandshakeLimits::max_minimum_depth`]: crate::util::config::ChannelHandshakeLimits::max_minimum_depth
+       pub confirmations_required: Option<u32>,
+       /// The number of blocks (after our commitment transaction confirms) that we will need to wait
+       /// until we can claim our funds after we force-close the channel. During this time our
+       /// counterparty is allowed to punish us if we broadcasted a stale state. If our counterparty
+       /// force-closes the channel and broadcasts a commitment transaction we do not have to wait any
+       /// time to claim our non-HTLC-encumbered funds.
+       ///
+       /// This value will be `None` for outbound channels until the counterparty accepts the channel.
+       pub force_close_spend_delay: Option<u16>,
        /// True if the channel was initiated (and thus funded) by us.
        pub is_outbound: bool,
        /// True if the channel is confirmed, funding_locked messages have been exchanged, and the
        /// channel is not currently being shut down. `funding_locked` message exchange implies the
        /// required confirmation count has been reached (and we were connected to the peer at some
-       /// point after the funding transaction received enough confirmations).
+       /// point after the funding transaction received enough confirmations). The required
+       /// confirmation count is provided in [`confirmations_required`].
+       ///
+       /// [`confirmations_required`]: ChannelDetails::confirmations_required
        pub is_funding_locked: bool,
        /// True if the channel is (a) confirmed and funding_locked messages have been exchanged, (b)
-       /// the peer is connected, (c) no monitor update failure is pending resolution, and (d) the
-       /// channel is not currently negotiating a shutdown.
+       /// the peer is connected, and (c) the channel is not currently negotiating a shutdown.
        ///
        /// This is a strict superset of `is_funding_locked`.
        pub is_usable: bool,
        /// True if this channel is (or will be) publicly-announced.
        pub is_public: bool,
-       /// Information on the fees and requirements that the counterparty requires when forwarding
-       /// payments to us through this channel.
-       pub counterparty_forwarding_info: Option<CounterpartyForwardingInfo>,
 }
 
 /// If a payment fails to send, it can be in one of several states. This enum is returned as the
@@ -1147,28 +1174,36 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                        res.reserve(channel_state.by_id.len());
                        for (channel_id, channel) in channel_state.by_id.iter().filter(f) {
                                let (inbound_capacity_msat, outbound_capacity_msat) = channel.get_inbound_outbound_available_balance_msat();
+                               let (to_remote_reserve_satoshis, to_self_reserve_satoshis) =
+                                       channel.get_holder_counterparty_selected_channel_reserve_satoshis();
                                res.push(ChannelDetails {
                                        channel_id: (*channel_id).clone(),
+                                       counterparty: ChannelCounterparty {
+                                               node_id: channel.get_counterparty_node_id(),
+                                               features: InitFeatures::empty(),
+                                               unspendable_punishment_reserve: to_remote_reserve_satoshis,
+                                               forwarding_info: channel.counterparty_forwarding_info(),
+                                       },
                                        funding_txo: channel.get_funding_txo(),
                                        short_channel_id: channel.get_short_channel_id(),
-                                       remote_network_id: channel.get_counterparty_node_id(),
-                                       counterparty_features: InitFeatures::empty(),
                                        channel_value_satoshis: channel.get_value_satoshis(),
+                                       unspendable_punishment_reserve: to_self_reserve_satoshis,
                                        inbound_capacity_msat,
                                        outbound_capacity_msat,
                                        user_id: channel.get_user_id(),
+                                       confirmations_required: channel.minimum_depth(),
+                                       force_close_spend_delay: channel.get_counterparty_selected_contest_delay(),
                                        is_outbound: channel.is_outbound(),
                                        is_funding_locked: channel.is_usable(),
                                        is_usable: channel.is_live(),
                                        is_public: channel.should_announce(),
-                                       counterparty_forwarding_info: channel.counterparty_forwarding_info(),
                                });
                        }
                }
                let per_peer_state = self.per_peer_state.read().unwrap();
                for chan in res.iter_mut() {
-                       if let Some(peer_state) = per_peer_state.get(&chan.remote_network_id) {
-                               chan.counterparty_features = peer_state.lock().unwrap().latest_features.clone();
+                       if let Some(peer_state) = per_peer_state.get(&chan.counterparty.node_id) {
+                               chan.counterparty.features = peer_state.lock().unwrap().latest_features.clone();
                        }
                }
                res
@@ -3346,14 +3381,15 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                Ok(())
        }
 
-       fn internal_channel_update(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelUpdate) -> Result<(), MsgHandleErrInternal> {
+       /// Returns ShouldPersist if anything changed, otherwise either SkipPersist or an Err.
+       fn internal_channel_update(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelUpdate) -> Result<NotifyOption, MsgHandleErrInternal> {
                let mut channel_state_lock = self.channel_state.lock().unwrap();
                let channel_state = &mut *channel_state_lock;
                let chan_id = match channel_state.short_to_id.get(&msg.contents.short_channel_id) {
                        Some(chan_id) => chan_id.clone(),
                        None => {
                                // It's not a local channel
-                               return Ok(())
+                               return Ok(NotifyOption::SkipPersist)
                        }
                };
                match channel_state.by_id.entry(chan_id) {
@@ -3363,7 +3399,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                // If the announcement is about a channel of ours which is public, some
                                                // other peer may simply be forwarding all its gossip to us. Don't provide
                                                // a scary-looking error message and return Ok instead.
-                                               return Ok(());
+                                               return Ok(NotifyOption::SkipPersist);
                                        }
                                        return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a channel_update for a channel from the wrong node - it shouldn't know about our private channels!".to_owned(), chan_id));
                                }
@@ -3371,7 +3407,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                        },
                        hash_map::Entry::Vacant(_) => unreachable!()
                }
-               Ok(())
+               Ok(NotifyOption::DoPersist)
        }
 
        fn internal_channel_reestablish(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(), MsgHandleErrInternal> {
@@ -4030,6 +4066,12 @@ where
                let guard = mtx.lock().unwrap();
                *guard
        }
+
+       /// Gets the latest best block which was connected either via the [`chain::Listen`] or
+       /// [`chain::Confirm`] interfaces.
+       pub fn current_best_block(&self) -> BestBlock {
+               self.best_block.read().unwrap().clone()
+       }
 }
 
 impl<Signer: Sign, M: Deref , T: Deref , K: Deref , F: Deref , L: Deref >
@@ -4116,8 +4158,13 @@ impl<Signer: Sign, M: Deref , T: Deref , K: Deref , F: Deref , L: Deref >
        }
 
        fn handle_channel_update(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelUpdate) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
-               let _ = handle_error!(self, self.internal_channel_update(counterparty_node_id, msg), *counterparty_node_id);
+               PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock, &self.persistence_notifier, || {
+                       if let Ok(persist) = handle_error!(self, self.internal_channel_update(counterparty_node_id, msg), *counterparty_node_id) {
+                               persist
+                       } else {
+                               NotifyOption::SkipPersist
+                       }
+               });
        }
 
        fn handle_channel_reestablish(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelReestablish) {
@@ -4249,7 +4296,7 @@ impl<Signer: Sign, M: Deref , T: Deref , K: Deref , F: Deref , L: Deref >
 
                if msg.channel_id == [0; 32] {
                        for chan in self.list_channels() {
-                               if chan.remote_network_id == *counterparty_node_id {
+                               if chan.counterparty.node_id == *counterparty_node_id {
                                        // Untrusted messages from peer, we throw away the error if id points to a non-existent channel
                                        let _ = self.force_close_channel_with_peer(&chan.channel_id, Some(counterparty_node_id));
                                }
@@ -4827,6 +4874,9 @@ mod tests {
        use core::sync::atomic::{AtomicBool, Ordering};
        use std::thread;
        use core::time::Duration;
+       use ln::functional_test_utils::*;
+       use ln::features::InitFeatures;
+       use ln::msgs::ChannelMessageHandler;
 
        #[test]
        fn test_wait_timeout() {
@@ -4869,6 +4919,53 @@ mod tests {
                        }
                }
        }
+
+       #[test]
+       fn test_notify_limits() {
+               // Check that a few cases which don't require the persistence of a new ChannelManager,
+               // indeed, do not cause the persistence of a new ChannelManager.
+               let chanmon_cfgs = create_chanmon_cfgs(3);
+               let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
+               let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
+               let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
+
+               let mut chan = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
+
+               // We check that the channel info nodes have doesn't change too early, even though we try
+               // to connect messages with new values
+               chan.0.contents.fee_base_msat *= 2;
+               chan.1.contents.fee_base_msat *= 2;
+               let node_a_chan_info = nodes[0].node.list_channels()[0].clone();
+               let node_b_chan_info = nodes[1].node.list_channels()[0].clone();
+
+               // The first two nodes (which opened a channel) should now require fresh persistence
+               assert!(nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               // ... but the last node should not.
+               assert!(!nodes[2].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               // After persisting the first two nodes they should no longer need fresh persistence.
+               assert!(!nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(!nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+
+               // Node 3, unrelated to the only channel, shouldn't care if it receives a channel_update
+               // about the channel.
+               nodes[2].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan.0);
+               nodes[2].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan.1);
+               assert!(!nodes[2].node.await_persistable_update_timeout(Duration::from_millis(1)));
+
+               // The nodes which are a party to the channel should also ignore messages from unrelated
+               // parties.
+               nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan.0);
+               nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan.1);
+               nodes[1].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan.0);
+               nodes[1].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan.1);
+               assert!(!nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(!nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+
+               // At this point the channel info given by peers should still be the same.
+               assert_eq!(nodes[0].node.list_channels()[0], node_a_chan_info);
+               assert_eq!(nodes[1].node.list_channels()[0], node_b_chan_info);
+       }
 }
 
 #[cfg(all(any(test, feature = "_test_utils"), feature = "unstable"))]