Add test coverage ChannelClosed event fields
[rust-lightning] / lightning / src / ln / peer_handler.rs
index 5c841d78aaee9b29ad4b4ce71a1369f0be883c56..1a39bbb3ae408e7047159e6d9f3f63267188b61f 100644 (file)
 //! call into the provided message handlers (probably a ChannelManager and P2PGossipSync) with
 //! messages they should handle, and encoding/sending response messages.
 
+use bitcoin::blockdata::constants::ChainHash;
 use bitcoin::secp256k1::{self, Secp256k1, SecretKey, PublicKey};
 
-use crate::chain::keysinterface::{KeysManager, NodeSigner, Recipient};
+use crate::sign::{KeysManager, NodeSigner, Recipient};
+use crate::events::{MessageSendEvent, MessageSendEventsProvider, OnionMessageProvider};
 use crate::ln::features::{InitFeatures, NodeFeatures};
 use crate::ln::msgs;
 use crate::ln::msgs::{ChannelMessageHandler, LightningError, NetAddress, OnionMessageHandler, RoutingMessageHandler};
@@ -25,18 +27,18 @@ use crate::ln::channelmanager::{SimpleArcChannelManager, SimpleRefChannelManager
 use crate::util::ser::{VecWriter, Writeable, Writer};
 use crate::ln::peer_channel_encryptor::{PeerChannelEncryptor,NextNoiseStep};
 use crate::ln::wire;
-use crate::ln::wire::Encode;
-use crate::onion_message::{CustomOnionMessageContents, CustomOnionMessageHandler, SimpleArcOnionMessenger, SimpleRefOnionMessenger};
-use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId};
+use crate::ln::wire::{Encode, Type};
+use crate::onion_message::{CustomOnionMessageContents, CustomOnionMessageHandler, OffersMessage, OffersMessageHandler, SimpleArcOnionMessenger, SimpleRefOnionMessenger};
+use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, NodeAlias};
 use crate::util::atomic_counter::AtomicCounter;
-use crate::util::events::{MessageSendEvent, MessageSendEventsProvider, OnionMessageProvider};
 use crate::util::logger::Logger;
+use crate::util::string::PrintableString;
 
 use crate::prelude::*;
 use crate::io;
 use alloc::collections::LinkedList;
 use crate::sync::{Arc, Mutex, MutexGuard, FairRwLock};
-use core::sync::atomic::{AtomicBool, AtomicU32, Ordering};
+use core::sync::atomic::{AtomicBool, AtomicU32, AtomicI32, Ordering};
 use core::{cmp, hash, fmt, mem};
 use core::ops::Deref;
 use core::convert::Infallible;
@@ -64,6 +66,20 @@ pub trait CustomMessageHandler: wire::CustomMessageReader {
        /// in the process. Each message is paired with the node id of the intended recipient. If no
        /// connection to the node exists, then the message is simply not sent.
        fn get_and_clear_pending_msg(&self) -> Vec<(PublicKey, Self::CustomMessage)>;
+
+       /// Gets the node feature flags which this handler itself supports. All available handlers are
+       /// queried similarly and their feature flags are OR'd together to form the [`NodeFeatures`]
+       /// which are broadcasted in our [`NodeAnnouncement`] message.
+       ///
+       /// [`NodeAnnouncement`]: crate::ln::msgs::NodeAnnouncement
+       fn provided_node_features(&self) -> NodeFeatures;
+
+       /// Gets the init feature flags which should be sent to the given peer. All available handlers
+       /// are queried similarly and their feature flags are OR'd together to form the [`InitFeatures`]
+       /// which are sent in our [`Init`] message.
+       ///
+       /// [`Init`]: crate::ln::msgs::Init
+       fn provided_init_features(&self, their_node_id: &PublicKey) -> InitFeatures;
 }
 
 /// A dummy struct which implements `RoutingMessageHandler` without storing any routing information
@@ -102,9 +118,12 @@ impl OnionMessageHandler for IgnoringMessageHandler {
                InitFeatures::empty()
        }
 }
+impl OffersMessageHandler for IgnoringMessageHandler {
+       fn handle_message(&self, _msg: OffersMessage) -> Option<OffersMessage> { None }
+}
 impl CustomOnionMessageHandler for IgnoringMessageHandler {
        type CustomMessage = Infallible;
-       fn handle_custom_message(&self, _msg: Infallible) {
+       fn handle_custom_message(&self, _msg: Infallible) -> Option<Infallible> {
                // Since we always return `None` in the read the handle method should never be called.
                unreachable!();
        }
@@ -149,6 +168,12 @@ impl CustomMessageHandler for IgnoringMessageHandler {
        }
 
        fn get_and_clear_pending_msg(&self) -> Vec<(PublicKey, Self::CustomMessage)> { Vec::new() }
+
+       fn provided_node_features(&self) -> NodeFeatures { NodeFeatures::empty() }
+
+       fn provided_init_features(&self, _their_node_id: &PublicKey) -> InitFeatures {
+               InitFeatures::empty()
+       }
 }
 
 /// A dummy struct which implements `ChannelMessageHandler` without having any channels.
@@ -252,17 +277,70 @@ impl ChannelMessageHandler for ErroringMessageHandler {
                features.set_zero_conf_optional();
                features
        }
+
+       fn get_genesis_hashes(&self) -> Option<Vec<ChainHash>> {
+               // We don't enforce any chains upon peer connection for `ErroringMessageHandler` and leave it up
+               // to users of `ErroringMessageHandler` to make decisions on network compatiblility.
+               // There's not really any way to pull in specific networks here, and hardcoding can cause breakages.
+               None
+       }
+
+       fn handle_open_channel_v2(&self, their_node_id: &PublicKey, msg: &msgs::OpenChannelV2) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.temporary_channel_id);
+       }
+
+       fn handle_accept_channel_v2(&self, their_node_id: &PublicKey, msg: &msgs::AcceptChannelV2) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.temporary_channel_id);
+       }
+
+       fn handle_tx_add_input(&self, their_node_id: &PublicKey, msg: &msgs::TxAddInput) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+
+       fn handle_tx_add_output(&self, their_node_id: &PublicKey, msg: &msgs::TxAddOutput) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+
+       fn handle_tx_remove_input(&self, their_node_id: &PublicKey, msg: &msgs::TxRemoveInput) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+
+       fn handle_tx_remove_output(&self, their_node_id: &PublicKey, msg: &msgs::TxRemoveOutput) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+
+       fn handle_tx_complete(&self, their_node_id: &PublicKey, msg: &msgs::TxComplete) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+
+       fn handle_tx_signatures(&self, their_node_id: &PublicKey, msg: &msgs::TxSignatures) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+
+       fn handle_tx_init_rbf(&self, their_node_id: &PublicKey, msg: &msgs::TxInitRbf) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+
+       fn handle_tx_ack_rbf(&self, their_node_id: &PublicKey, msg: &msgs::TxAckRbf) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+
+       fn handle_tx_abort(&self, their_node_id: &PublicKey, msg: &msgs::TxAbort) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
 }
+
 impl Deref for ErroringMessageHandler {
        type Target = ErroringMessageHandler;
        fn deref(&self) -> &Self { self }
 }
 
 /// Provides references to trait impls which handle different types of messages.
-pub struct MessageHandler<CM: Deref, RM: Deref, OM: Deref> where
-               CM::Target: ChannelMessageHandler,
-               RM::Target: RoutingMessageHandler,
-               OM::Target: OnionMessageHandler,
+pub struct MessageHandler<CM: Deref, RM: Deref, OM: Deref, CustomM: Deref> where
+       CM::Target: ChannelMessageHandler,
+       RM::Target: RoutingMessageHandler,
+       OM::Target: OnionMessageHandler,
+       CustomM::Target: CustomMessageHandler,
 {
        /// A message handler which handles messages specific to channels. Usually this is just a
        /// [`ChannelManager`] object or an [`ErroringMessageHandler`].
@@ -275,9 +353,15 @@ pub struct MessageHandler<CM: Deref, RM: Deref, OM: Deref> where
        /// [`P2PGossipSync`]: crate::routing::gossip::P2PGossipSync
        pub route_handler: RM,
 
-       /// A message handler which handles onion messages. For now, this can only be an
-       /// [`IgnoringMessageHandler`].
+       /// A message handler which handles onion messages. This should generally be an
+       /// [`OnionMessenger`], but can also be an [`IgnoringMessageHandler`].
+       ///
+       /// [`OnionMessenger`]: crate::onion_message::OnionMessenger
        pub onion_message_handler: OM,
+
+       /// A message handler which handles custom messages. The only LDK-provided implementation is
+       /// [`IgnoringMessageHandler`].
+       pub custom_message_handler: CustomM,
 }
 
 /// Provides an object which can be used to send data to and which uniquely identifies a connection
@@ -416,7 +500,7 @@ struct Peer {
        sync_status: InitSyncTracker,
 
        msgs_sent_since_pong: usize,
-       awaiting_pong_timer_tick_intervals: i8,
+       awaiting_pong_timer_tick_intervals: i64,
        received_message_since_timer_tick: bool,
        sent_gossip_timestamp_filter: bool,
 
@@ -523,7 +607,15 @@ impl Peer {
 /// issues such as overly long function definitions.
 ///
 /// This is not exported to bindings users as `Arc`s don't make sense in bindings.
-pub type SimpleArcPeerManager<SD, M, T, F, C, L> = PeerManager<SD, Arc<SimpleArcChannelManager<M, T, F, L>>, Arc<P2PGossipSync<Arc<NetworkGraph<Arc<L>>>, Arc<C>, Arc<L>>>, Arc<SimpleArcOnionMessenger<L>>, Arc<L>, IgnoringMessageHandler, Arc<KeysManager>>;
+pub type SimpleArcPeerManager<SD, M, T, F, C, L> = PeerManager<
+       SD,
+       Arc<SimpleArcChannelManager<M, T, F, L>>,
+       Arc<P2PGossipSync<Arc<NetworkGraph<Arc<L>>>, Arc<C>, Arc<L>>>,
+       Arc<SimpleArcOnionMessenger<L>>,
+       Arc<L>,
+       IgnoringMessageHandler,
+       Arc<KeysManager>
+>;
 
 /// SimpleRefPeerManager is a type alias for a PeerManager reference, and is the reference
 /// counterpart to the SimpleArcPeerManager type alias. Use this type by default when you don't
@@ -533,7 +625,68 @@ pub type SimpleArcPeerManager<SD, M, T, F, C, L> = PeerManager<SD, Arc<SimpleArc
 /// helps with issues such as long function definitions.
 ///
 /// This is not exported to bindings users as general type aliases don't make sense in bindings.
-pub type SimpleRefPeerManager<'a, 'b, 'c, 'd, 'e, 'f, 'g, 'h, 'i, 'j, 'k, 'l, 'm, SD, M, T, F, C, L> = PeerManager<SD, SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, 'f, 'g, 'm, M, T, F, L>, &'f P2PGossipSync<&'g NetworkGraph<&'f L>, &'h C, &'f L>, &'i SimpleRefOnionMessenger<'j, 'k, L>, &'f L, IgnoringMessageHandler, &'c KeysManager>;
+pub type SimpleRefPeerManager<
+       'a, 'b, 'c, 'd, 'e, 'f, 'g, 'h, 'i, 'j, 'k, 'l, 'm, 'n, SD, M, T, F, C, L
+> = PeerManager<
+       SD,
+       &'n SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, 'f, 'g, 'm, M, T, F, L>,
+       &'f P2PGossipSync<&'g NetworkGraph<&'f L>, &'h C, &'f L>,
+       &'i SimpleRefOnionMessenger<'g, 'm, 'n, L>,
+       &'f L,
+       IgnoringMessageHandler,
+       &'c KeysManager
+>;
+
+
+/// A generic trait which is implemented for all [`PeerManager`]s. This makes bounding functions or
+/// structs on any [`PeerManager`] much simpler as only this trait is needed as a bound, rather
+/// than the full set of bounds on [`PeerManager`] itself.
+///
+/// This is not exported to bindings users as general cover traits aren't useful in other
+/// languages.
+#[allow(missing_docs)]
+pub trait APeerManager {
+       type Descriptor: SocketDescriptor;
+       type CMT: ChannelMessageHandler + ?Sized;
+       type CM: Deref<Target=Self::CMT>;
+       type RMT: RoutingMessageHandler + ?Sized;
+       type RM: Deref<Target=Self::RMT>;
+       type OMT: OnionMessageHandler + ?Sized;
+       type OM: Deref<Target=Self::OMT>;
+       type LT: Logger + ?Sized;
+       type L: Deref<Target=Self::LT>;
+       type CMHT: CustomMessageHandler + ?Sized;
+       type CMH: Deref<Target=Self::CMHT>;
+       type NST: NodeSigner + ?Sized;
+       type NS: Deref<Target=Self::NST>;
+       /// Gets a reference to the underlying [`PeerManager`].
+       fn as_ref(&self) -> &PeerManager<Self::Descriptor, Self::CM, Self::RM, Self::OM, Self::L, Self::CMH, Self::NS>;
+}
+
+impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CMH: Deref, NS: Deref>
+APeerManager for PeerManager<Descriptor, CM, RM, OM, L, CMH, NS> where
+       CM::Target: ChannelMessageHandler,
+       RM::Target: RoutingMessageHandler,
+       OM::Target: OnionMessageHandler,
+       L::Target: Logger,
+       CMH::Target: CustomMessageHandler,
+       NS::Target: NodeSigner,
+{
+       type Descriptor = Descriptor;
+       type CMT = <CM as Deref>::Target;
+       type CM = CM;
+       type RMT = <RM as Deref>::Target;
+       type RM = RM;
+       type OMT = <OM as Deref>::Target;
+       type OM = OM;
+       type LT = <L as Deref>::Target;
+       type L = L;
+       type CMHT = <CMH as Deref>::Target;
+       type CMH = CMH;
+       type NST = <NS as Deref>::Target;
+       type NS = NS;
+       fn as_ref(&self) -> &PeerManager<Descriptor, CM, RM, OM, L, CMH, NS> { self }
+}
 
 /// A PeerManager manages a set of peers, described by their [`SocketDescriptor`] and marshalls
 /// socket events into messages which it passes on to its [`MessageHandler`].
@@ -561,7 +714,7 @@ pub struct PeerManager<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: D
                L::Target: Logger,
                CMH::Target: CustomMessageHandler,
                NS::Target: NodeSigner {
-       message_handler: MessageHandler<CM, RM, OM>,
+       message_handler: MessageHandler<CM, RM, OM, CMH>,
        /// Connection state for each connected peer - we have an outer read-write lock which is taken
        /// as read while we're doing processing for a peer and taken write when a peer is being added
        /// or removed.
@@ -576,22 +729,24 @@ pub struct PeerManager<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: D
        /// lock held. Entries may be added with only the `peers` read lock held (though the
        /// `Descriptor` value must already exist in `peers`).
        node_id_to_descriptor: Mutex<HashMap<PublicKey, Descriptor>>,
-       /// We can only have one thread processing events at once, but we don't usually need the full
-       /// `peers` write lock to do so, so instead we block on this empty mutex when entering
-       /// `process_events`.
-       event_processing_lock: Mutex<()>,
-       /// Because event processing is global and always does all available work before returning,
-       /// there is no reason for us to have many event processors waiting on the lock at once.
-       /// Instead, we limit the total blocked event processors to always exactly one by setting this
-       /// when an event process call is waiting.
-       blocked_event_processors: AtomicBool,
+       /// We can only have one thread processing events at once, but if a second call to
+       /// `process_events` happens while a first call is in progress, one of the two calls needs to
+       /// start from the top to ensure any new messages are also handled.
+       ///
+       /// Because the event handler calls into user code which may block, we don't want to block a
+       /// second thread waiting for another thread to handle events which is then blocked on user
+       /// code, so we store an atomic counter here:
+       ///  * 0 indicates no event processor is running
+       ///  * 1 indicates an event processor is running
+       ///  * > 1 indicates an event processor is running but needs to start again from the top once
+       ///        it finishes as another thread tried to start processing events but returned early.
+       event_processing_state: AtomicI32,
 
        /// Used to track the last value sent in a node_announcement "timestamp" field. We ensure this
        /// value increases strictly since we don't assume access to a time source.
        last_node_announcement_serial: AtomicU32,
 
        ephemeral_key_midstate: Sha256Engine,
-       custom_message_handler: CMH,
 
        peer_counter: AtomicCounter,
 
@@ -652,7 +807,8 @@ impl<Descriptor: SocketDescriptor, CM: Deref, OM: Deref, L: Deref, NS: Deref> Pe
                        chan_handler: channel_message_handler,
                        route_handler: IgnoringMessageHandler{},
                        onion_message_handler,
-               }, current_time, ephemeral_random_data, logger, IgnoringMessageHandler{}, node_signer)
+                       custom_message_handler: IgnoringMessageHandler{},
+               }, current_time, ephemeral_random_data, logger, node_signer)
        }
 }
 
@@ -679,7 +835,8 @@ impl<Descriptor: SocketDescriptor, RM: Deref, L: Deref, NS: Deref> PeerManager<D
                        chan_handler: ErroringMessageHandler::new(),
                        route_handler: routing_message_handler,
                        onion_message_handler: IgnoringMessageHandler{},
-               }, current_time, ephemeral_random_data, logger, IgnoringMessageHandler{}, node_signer)
+                       custom_message_handler: IgnoringMessageHandler{},
+               }, current_time, ephemeral_random_data, logger, node_signer)
        }
 }
 
@@ -741,7 +898,7 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
        /// incremented irregularly internally. In general it is best to simply use the current UNIX
        /// timestamp, however if it is not available a persistent counter that increases once per
        /// minute should suffice.
-       pub fn new(message_handler: MessageHandler<CM, RM, OM>, current_time: u32, ephemeral_random_data: &[u8; 32], logger: L, custom_message_handler: CMH, node_signer: NS) -> Self {
+       pub fn new(message_handler: MessageHandler<CM, RM, OM, CMH>, current_time: u32, ephemeral_random_data: &[u8; 32], logger: L, node_signer: NS) -> Self {
                let mut ephemeral_key_midstate = Sha256::engine();
                ephemeral_key_midstate.input(ephemeral_random_data);
 
@@ -753,15 +910,13 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                        message_handler,
                        peers: FairRwLock::new(HashMap::new()),
                        node_id_to_descriptor: Mutex::new(HashMap::new()),
-                       event_processing_lock: Mutex::new(()),
-                       blocked_event_processors: AtomicBool::new(false),
+                       event_processing_state: AtomicI32::new(0),
                        ephemeral_key_midstate,
                        peer_counter: AtomicCounter::new(),
                        gossip_processing_backlogged: AtomicBool::new(false),
                        gossip_processing_backlog_lifted: AtomicBool::new(false),
                        last_node_announcement_serial: AtomicU32::new(current_time),
                        logger,
-                       custom_message_handler,
                        node_signer,
                        secp_ctx,
                }
@@ -795,6 +950,13 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                SecretKey::from_slice(&Sha256::from_engine(ephemeral_hash).into_inner()).expect("You broke SHA-256!")
        }
 
+       fn init_features(&self, their_node_id: &PublicKey) -> InitFeatures {
+               self.message_handler.chan_handler.provided_init_features(their_node_id)
+                       | self.message_handler.route_handler.provided_init_features(their_node_id)
+                       | self.message_handler.onion_message_handler.provided_init_features(their_node_id)
+                       | self.message_handler.custom_message_handler.provided_init_features(their_node_id)
+       }
+
        /// Indicates a new outbound connection has been established to a node with the given `node_id`
        /// and an optional remote network address.
        ///
@@ -1056,7 +1218,7 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                match self.do_read_event(peer_descriptor, data) {
                        Ok(res) => Ok(res),
                        Err(e) => {
-                               log_trace!(self.logger, "Peer sent invalid data or we decided to disconnect due to a protocol error");
+                               log_trace!(self.logger, "Disconnecting peer due to a protocol error (usually a duplicate connection).");
                                self.disconnect_event_internal(peer_descriptor);
                                Err(e)
                        }
@@ -1101,8 +1263,21 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                                                                Ok(x) => x,
                                                                Err(e) => {
                                                                        match e.action {
-                                                                               msgs::ErrorAction::DisconnectPeer { msg: _ } => {
-                                                                                       //TODO: Try to push msg
+                                                                               msgs::ErrorAction::DisconnectPeer { .. } => {
+                                                                                       // We may have an `ErrorMessage` to send to the peer,
+                                                                                       // but writing to the socket while reading can lead to
+                                                                                       // re-entrant code and possibly unexpected behavior. The
+                                                                                       // message send is optimistic anyway, and in this case
+                                                                                       // we immediately disconnect the peer.
+                                                                                       log_debug!(self.logger, "Error handling message{}; disconnecting peer with: {}", OptionalFromDebugger(&peer_node_id), e.err);
+                                                                                       return Err(PeerHandleError { });
+                                                                               },
+                                                                               msgs::ErrorAction::DisconnectPeerWithWarning { .. } => {
+                                                                                       // We have a `WarningMessage` to send to the peer, but
+                                                                                       // writing to the socket while reading can lead to
+                                                                                       // re-entrant code and possibly unexpected behavior. The
+                                                                                       // message send is optimistic anyway, and in this case
+                                                                                       // we immediately disconnect the peer.
                                                                                        log_debug!(self.logger, "Error handling message{}; disconnecting peer with: {}", OptionalFromDebugger(&peer_node_id), e.err);
                                                                                        return Err(PeerHandleError { });
                                                                                },
@@ -1190,10 +1365,9 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
 
                                                                peer.set_their_node_id(their_node_id);
                                                                insert_node_id!();
-                                                               let features = self.message_handler.chan_handler.provided_init_features(&their_node_id)
-                                                                       .or(self.message_handler.route_handler.provided_init_features(&their_node_id))
-                                                                       .or(self.message_handler.onion_message_handler.provided_init_features(&their_node_id));
-                                                               let resp = msgs::Init { features, remote_network_address: filter_addresses(peer.their_net_address.clone()) };
+                                                               let features = self.init_features(&their_node_id);
+                                                               let networks = self.message_handler.chan_handler.get_genesis_hashes();
+                                                               let resp = msgs::Init { features, networks, remote_network_address: filter_addresses(peer.their_net_address.clone()) };
                                                                self.enqueue_message(peer, &resp);
                                                                peer.awaiting_pong_timer_tick_intervals = 0;
                                                        },
@@ -1204,10 +1378,9 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                                                                peer.pending_read_is_header = true;
                                                                peer.set_their_node_id(their_node_id);
                                                                insert_node_id!();
-                                                               let features = self.message_handler.chan_handler.provided_init_features(&their_node_id)
-                                                                       .or(self.message_handler.route_handler.provided_init_features(&their_node_id))
-                                                                       .or(self.message_handler.onion_message_handler.provided_init_features(&their_node_id));
-                                                               let resp = msgs::Init { features, remote_network_address: filter_addresses(peer.their_net_address.clone()) };
+                                                               let features = self.init_features(&their_node_id);
+                                                               let networks = self.message_handler.chan_handler.get_genesis_hashes();
+                                                               let resp = msgs::Init { features, networks, remote_network_address: filter_addresses(peer.their_net_address.clone()) };
                                                                self.enqueue_message(peer, &resp);
                                                                peer.awaiting_pong_timer_tick_intervals = 0;
                                                        },
@@ -1232,12 +1405,12 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                                                                        peer.pending_read_is_header = true;
 
                                                                        let mut reader = io::Cursor::new(&msg_data[..]);
-                                                                       let message_result = wire::read(&mut reader, &*self.custom_message_handler);
+                                                                       let message_result = wire::read(&mut reader, &*self.message_handler.custom_message_handler);
                                                                        let message = match message_result {
                                                                                Ok(x) => x,
                                                                                Err(e) => {
                                                                                        match e {
-                                                                                               // Note that to avoid recursion we never call
+                                                                                               // Note that to avoid re-entrancy we never call
                                                                                                // `do_attempt_write_data` from here, causing
                                                                                                // the messages enqueued here to not actually
                                                                                                // be sent before the peer is disconnected.
@@ -1258,9 +1431,8 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                                                                                                        });
                                                                                                        continue;
                                                                                                }
-                                                                                               (msgs::DecodeError::UnknownRequiredFeature, ty) => {
-                                                                                                       log_gossip!(self.logger, "Received a message with an unknown required feature flag or TLV, you may want to update!");
-                                                                                                       self.enqueue_message(peer, &msgs::WarningMessage { channel_id: [0; 32], data: format!("Received an unknown required feature/TLV in message type {:?}", ty) });
+                                                                                               (msgs::DecodeError::UnknownRequiredFeature, _) => {
+                                                                                                       log_debug!(self.logger, "Received a message with an unknown required feature flag or TLV, you may want to update!");
                                                                                                        return Err(PeerHandleError { });
                                                                                                }
                                                                                                (msgs::DecodeError::UnknownVersion, _) => return Err(PeerHandleError { }),
@@ -1323,10 +1495,36 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
 
                // Need an Init as first message
                if let wire::Message::Init(msg) = message {
-                       if msg.features.requires_unknown_bits() {
-                               log_debug!(self.logger, "Peer features required unknown version bits");
+                       // Check if we have any compatible chains if the `networks` field is specified.
+                       if let Some(networks) = &msg.networks {
+                               if let Some(our_chains) = self.message_handler.chan_handler.get_genesis_hashes() {
+                                       let mut have_compatible_chains = false;
+                                       'our_chains: for our_chain in our_chains.iter() {
+                                               for their_chain in networks {
+                                                       if our_chain == their_chain {
+                                                               have_compatible_chains = true;
+                                                               break 'our_chains;
+                                                       }
+                                               }
+                                       }
+                                       if !have_compatible_chains {
+                                               log_debug!(self.logger, "Peer does not support any of our supported chains");
+                                               return Err(PeerHandleError { }.into());
+                                       }
+                               }
+                       }
+
+                       let our_features = self.init_features(&their_node_id);
+                       if msg.features.requires_unknown_bits_from(&our_features) {
+                               log_debug!(self.logger, "Peer requires features unknown to us");
                                return Err(PeerHandleError { }.into());
                        }
+
+                       if our_features.requires_unknown_bits_from(&msg.features) {
+                               log_debug!(self.logger, "We require features unknown to our peer");
+                               return Err(PeerHandleError { }.into());
+                       }
+
                        if peer_lock.their_features.is_some() {
                                return Err(PeerHandleError { }.into());
                        }
@@ -1392,38 +1590,14 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                                // Handled above
                        },
                        wire::Message::Error(msg) => {
-                               let mut data_is_printable = true;
-                               for b in msg.data.bytes() {
-                                       if b < 32 || b > 126 {
-                                               data_is_printable = false;
-                                               break;
-                                       }
-                               }
-
-                               if data_is_printable {
-                                       log_debug!(self.logger, "Got Err message from {}: {}", log_pubkey!(their_node_id), msg.data);
-                               } else {
-                                       log_debug!(self.logger, "Got Err message from {} with non-ASCII error message", log_pubkey!(their_node_id));
-                               }
+                               log_debug!(self.logger, "Got Err message from {}: {}", log_pubkey!(their_node_id), PrintableString(&msg.data));
                                self.message_handler.chan_handler.handle_error(&their_node_id, &msg);
                                if msg.channel_id == [0; 32] {
                                        return Err(PeerHandleError { }.into());
                                }
                        },
                        wire::Message::Warning(msg) => {
-                               let mut data_is_printable = true;
-                               for b in msg.data.bytes() {
-                                       if b < 32 || b > 126 {
-                                               data_is_printable = false;
-                                               break;
-                                       }
-                               }
-
-                               if data_is_printable {
-                                       log_debug!(self.logger, "Got warning message from {}: {}", log_pubkey!(their_node_id), msg.data);
-                               } else {
-                                       log_debug!(self.logger, "Got warning message from {} with non-ASCII error message", log_pubkey!(their_node_id));
-                               }
+                               log_debug!(self.logger, "Got warning message from {}: {}", log_pubkey!(their_node_id), PrintableString(&msg.data));
                        },
 
                        wire::Message::Ping(msg) => {
@@ -1442,9 +1616,15 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                        wire::Message::OpenChannel(msg) => {
                                self.message_handler.chan_handler.handle_open_channel(&their_node_id, &msg);
                        },
+                       wire::Message::OpenChannelV2(msg) => {
+                               self.message_handler.chan_handler.handle_open_channel_v2(&their_node_id, &msg);
+                       },
                        wire::Message::AcceptChannel(msg) => {
                                self.message_handler.chan_handler.handle_accept_channel(&their_node_id, &msg);
                        },
+                       wire::Message::AcceptChannelV2(msg) => {
+                               self.message_handler.chan_handler.handle_accept_channel_v2(&their_node_id, &msg);
+                       },
 
                        wire::Message::FundingCreated(msg) => {
                                self.message_handler.chan_handler.handle_funding_created(&their_node_id, &msg);
@@ -1456,6 +1636,35 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                                self.message_handler.chan_handler.handle_channel_ready(&their_node_id, &msg);
                        },
 
+                       // Interactive transaction construction messages:
+                       wire::Message::TxAddInput(msg) => {
+                               self.message_handler.chan_handler.handle_tx_add_input(&their_node_id, &msg);
+                       },
+                       wire::Message::TxAddOutput(msg) => {
+                               self.message_handler.chan_handler.handle_tx_add_output(&their_node_id, &msg);
+                       },
+                       wire::Message::TxRemoveInput(msg) => {
+                               self.message_handler.chan_handler.handle_tx_remove_input(&their_node_id, &msg);
+                       },
+                       wire::Message::TxRemoveOutput(msg) => {
+                               self.message_handler.chan_handler.handle_tx_remove_output(&their_node_id, &msg);
+                       },
+                       wire::Message::TxComplete(msg) => {
+                               self.message_handler.chan_handler.handle_tx_complete(&their_node_id, &msg);
+                       },
+                       wire::Message::TxSignatures(msg) => {
+                               self.message_handler.chan_handler.handle_tx_signatures(&their_node_id, &msg);
+                       },
+                       wire::Message::TxInitRbf(msg) => {
+                               self.message_handler.chan_handler.handle_tx_init_rbf(&their_node_id, &msg);
+                       },
+                       wire::Message::TxAckRbf(msg) => {
+                               self.message_handler.chan_handler.handle_tx_ack_rbf(&their_node_id, &msg);
+                       },
+                       wire::Message::TxAbort(msg) => {
+                               self.message_handler.chan_handler.handle_tx_abort(&their_node_id, &msg);
+                       }
+
                        wire::Message::Shutdown(msg) => {
                                self.message_handler.chan_handler.handle_shutdown(&their_node_id, &msg);
                        },
@@ -1543,7 +1752,7 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                                log_trace!(self.logger, "Received unknown odd message of type {}, ignoring", type_id);
                        },
                        wire::Message::Custom(custom) => {
-                               self.custom_message_handler.handle_custom_message(custom, &their_node_id)?;
+                               self.message_handler.custom_message_handler.handle_custom_message(custom, &their_node_id)?;
                        },
                };
                Ok(should_forward)
@@ -1649,290 +1858,364 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
        /// [`ChannelManager::process_pending_htlc_forwards`]: crate::ln::channelmanager::ChannelManager::process_pending_htlc_forwards
        /// [`send_data`]: SocketDescriptor::send_data
        pub fn process_events(&self) {
-               let mut _single_processor_lock = self.event_processing_lock.try_lock();
-               if _single_processor_lock.is_err() {
-                       // While we could wake the older sleeper here with a CV and make more even waiting
-                       // times, that would be a lot of overengineering for a simple "reduce total waiter
-                       // count" goal.
-                       match self.blocked_event_processors.compare_exchange(false, true, Ordering::AcqRel, Ordering::Acquire) {
-                               Err(val) => {
-                                       debug_assert!(val, "compare_exchange failed spuriously?");
-                                       return;
-                               },
-                               Ok(val) => {
-                                       debug_assert!(!val, "compare_exchange succeeded spuriously?");
-                                       // We're the only waiter, as the running process_events may have emptied the
-                                       // pending events "long" ago and there are new events for us to process, wait until
-                                       // its done and process any leftover events before returning.
-                                       _single_processor_lock = Ok(self.event_processing_lock.lock().unwrap());
-                                       self.blocked_event_processors.store(false, Ordering::Release);
-                               }
-                       }
+               if self.event_processing_state.fetch_add(1, Ordering::AcqRel) > 0 {
+                       // If we're not the first event processor to get here, just return early, the increment
+                       // we just did will be treated as "go around again" at the end.
+                       return;
                }
 
-               self.update_gossip_backlogged();
-               let flush_read_disabled = self.gossip_processing_backlog_lifted.swap(false, Ordering::Relaxed);
-
-               let mut peers_to_disconnect = HashMap::new();
-               let mut events_generated = self.message_handler.chan_handler.get_and_clear_pending_msg_events();
-               events_generated.append(&mut self.message_handler.route_handler.get_and_clear_pending_msg_events());
+               loop {
+                       self.update_gossip_backlogged();
+                       let flush_read_disabled = self.gossip_processing_backlog_lifted.swap(false, Ordering::Relaxed);
 
-               {
-                       // TODO: There are some DoS attacks here where you can flood someone's outbound send
-                       // buffer by doing things like announcing channels on another node. We should be willing to
-                       // drop optional-ish messages when send buffers get full!
+                       let mut peers_to_disconnect = HashMap::new();
+                       let mut events_generated = self.message_handler.chan_handler.get_and_clear_pending_msg_events();
+                       events_generated.append(&mut self.message_handler.route_handler.get_and_clear_pending_msg_events());
 
-                       let peers_lock = self.peers.read().unwrap();
-                       let peers = &*peers_lock;
-                       macro_rules! get_peer_for_forwarding {
-                               ($node_id: expr) => {
-                                       {
-                                               if peers_to_disconnect.get($node_id).is_some() {
-                                                       // If we've "disconnected" this peer, do not send to it.
-                                                       continue;
-                                               }
-                                               let descriptor_opt = self.node_id_to_descriptor.lock().unwrap().get($node_id).cloned();
-                                               match descriptor_opt {
-                                                       Some(descriptor) => match peers.get(&descriptor) {
-                                                               Some(peer_mutex) => {
-                                                                       let peer_lock = peer_mutex.lock().unwrap();
-                                                                       if !peer_lock.handshake_complete() {
+                       {
+                               // TODO: There are some DoS attacks here where you can flood someone's outbound send
+                               // buffer by doing things like announcing channels on another node. We should be willing to
+                               // drop optional-ish messages when send buffers get full!
+
+                               let peers_lock = self.peers.read().unwrap();
+                               let peers = &*peers_lock;
+                               macro_rules! get_peer_for_forwarding {
+                                       ($node_id: expr) => {
+                                               {
+                                                       if peers_to_disconnect.get($node_id).is_some() {
+                                                               // If we've "disconnected" this peer, do not send to it.
+                                                               continue;
+                                                       }
+                                                       let descriptor_opt = self.node_id_to_descriptor.lock().unwrap().get($node_id).cloned();
+                                                       match descriptor_opt {
+                                                               Some(descriptor) => match peers.get(&descriptor) {
+                                                                       Some(peer_mutex) => {
+                                                                               let peer_lock = peer_mutex.lock().unwrap();
+                                                                               if !peer_lock.handshake_complete() {
+                                                                                       continue;
+                                                                               }
+                                                                               peer_lock
+                                                                       },
+                                                                       None => {
+                                                                               debug_assert!(false, "Inconsistent peers set state!");
                                                                                continue;
                                                                        }
-                                                                       peer_lock
                                                                },
                                                                None => {
-                                                                       debug_assert!(false, "Inconsistent peers set state!");
                                                                        continue;
-                                                               }
-                                                       },
-                                                       None => {
-                                                               continue;
-                                                       },
+                                                               },
+                                                       }
                                                }
                                        }
                                }
-                       }
-                       for event in events_generated.drain(..) {
-                               match event {
-                                       MessageSendEvent::SendAcceptChannel { ref node_id, ref msg } => {
-                                               log_debug!(self.logger, "Handling SendAcceptChannel event in peer_handler for node {} for channel {}",
-                                                               log_pubkey!(node_id),
-                                                               log_bytes!(msg.temporary_channel_id));
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       },
-                                       MessageSendEvent::SendOpenChannel { ref node_id, ref msg } => {
-                                               log_debug!(self.logger, "Handling SendOpenChannel event in peer_handler for node {} for channel {}",
-                                                               log_pubkey!(node_id),
-                                                               log_bytes!(msg.temporary_channel_id));
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       },
-                                       MessageSendEvent::SendFundingCreated { ref node_id, ref msg } => {
-                                               log_debug!(self.logger, "Handling SendFundingCreated event in peer_handler for node {} for channel {} (which becomes {})",
-                                                               log_pubkey!(node_id),
-                                                               log_bytes!(msg.temporary_channel_id),
-                                                               log_funding_channel_id!(msg.funding_txid, msg.funding_output_index));
-                                               // TODO: If the peer is gone we should generate a DiscardFunding event
-                                               // indicating to the wallet that they should just throw away this funding transaction
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       },
-                                       MessageSendEvent::SendFundingSigned { ref node_id, ref msg } => {
-                                               log_debug!(self.logger, "Handling SendFundingSigned event in peer_handler for node {} for channel {}",
-                                                               log_pubkey!(node_id),
-                                                               log_bytes!(msg.channel_id));
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       },
-                                       MessageSendEvent::SendChannelReady { ref node_id, ref msg } => {
-                                               log_debug!(self.logger, "Handling SendChannelReady event in peer_handler for node {} for channel {}",
-                                                               log_pubkey!(node_id),
-                                                               log_bytes!(msg.channel_id));
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       },
-                                       MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => {
-                                               log_debug!(self.logger, "Handling SendAnnouncementSignatures event in peer_handler for node {} for channel {})",
-                                                               log_pubkey!(node_id),
-                                                               log_bytes!(msg.channel_id));
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       },
-                                       MessageSendEvent::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, ref update_fee, ref commitment_signed } } => {
-                                               log_debug!(self.logger, "Handling UpdateHTLCs event in peer_handler for node {} with {} adds, {} fulfills, {} fails for channel {}",
-                                                               log_pubkey!(node_id),
-                                                               update_add_htlcs.len(),
-                                                               update_fulfill_htlcs.len(),
-                                                               update_fail_htlcs.len(),
-                                                               log_bytes!(commitment_signed.channel_id));
-                                               let mut peer = get_peer_for_forwarding!(node_id);
-                                               for msg in update_add_htlcs {
-                                                       self.enqueue_message(&mut *peer, msg);
-                                               }
-                                               for msg in update_fulfill_htlcs {
-                                                       self.enqueue_message(&mut *peer, msg);
-                                               }
-                                               for msg in update_fail_htlcs {
-                                                       self.enqueue_message(&mut *peer, msg);
-                                               }
-                                               for msg in update_fail_malformed_htlcs {
-                                                       self.enqueue_message(&mut *peer, msg);
-                                               }
-                                               if let &Some(ref msg) = update_fee {
-                                                       self.enqueue_message(&mut *peer, msg);
-                                               }
-                                               self.enqueue_message(&mut *peer, commitment_signed);
-                                       },
-                                       MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => {
-                                               log_debug!(self.logger, "Handling SendRevokeAndACK event in peer_handler for node {} for channel {}",
-                                                               log_pubkey!(node_id),
-                                                               log_bytes!(msg.channel_id));
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       },
-                                       MessageSendEvent::SendClosingSigned { ref node_id, ref msg } => {
-                                               log_debug!(self.logger, "Handling SendClosingSigned event in peer_handler for node {} for channel {}",
-                                                               log_pubkey!(node_id),
-                                                               log_bytes!(msg.channel_id));
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       },
-                                       MessageSendEvent::SendShutdown { ref node_id, ref msg } => {
-                                               log_debug!(self.logger, "Handling Shutdown event in peer_handler for node {} for channel {}",
-                                                               log_pubkey!(node_id),
-                                                               log_bytes!(msg.channel_id));
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       },
-                                       MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => {
-                                               log_debug!(self.logger, "Handling SendChannelReestablish event in peer_handler for node {} for channel {}",
-                                                               log_pubkey!(node_id),
-                                                               log_bytes!(msg.channel_id));
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       },
-                                       MessageSendEvent::SendChannelAnnouncement { ref node_id, ref msg, ref update_msg } => {
-                                               log_debug!(self.logger, "Handling SendChannelAnnouncement event in peer_handler for node {} for short channel id {}",
-                                                               log_pubkey!(node_id),
-                                                               msg.contents.short_channel_id);
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), update_msg);
-                                       },
-                                       MessageSendEvent::BroadcastChannelAnnouncement { msg, update_msg } => {
-                                               log_debug!(self.logger, "Handling BroadcastChannelAnnouncement event in peer_handler for short channel id {}", msg.contents.short_channel_id);
-                                               match self.message_handler.route_handler.handle_channel_announcement(&msg) {
-                                                       Ok(_) | Err(LightningError { action: msgs::ErrorAction::IgnoreDuplicateGossip, .. }) =>
-                                                               self.forward_broadcast_msg(peers, &wire::Message::ChannelAnnouncement(msg), None),
-                                                       _ => {},
-                                               }
-                                               if let Some(msg) = update_msg {
+                               for event in events_generated.drain(..) {
+                                       match event {
+                                               MessageSendEvent::SendAcceptChannel { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendAcceptChannel event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.temporary_channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendAcceptChannelV2 { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendAcceptChannelV2 event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.temporary_channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendOpenChannel { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendOpenChannel event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.temporary_channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendOpenChannelV2 { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendOpenChannelV2 event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.temporary_channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendFundingCreated { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendFundingCreated event in peer_handler for node {} for channel {} (which becomes {})",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.temporary_channel_id),
+                                                                       log_funding_channel_id!(msg.funding_txid, msg.funding_output_index));
+                                                       // TODO: If the peer is gone we should generate a DiscardFunding event
+                                                       // indicating to the wallet that they should just throw away this funding transaction
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendFundingSigned { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendFundingSigned event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendChannelReady { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendChannelReady event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendTxAddInput { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendTxAddInput event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendTxAddOutput { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendTxAddOutput event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendTxRemoveInput { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendTxRemoveInput event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendTxRemoveOutput { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendTxRemoveOutput event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendTxComplete { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendTxComplete event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendTxSignatures { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendTxSignatures event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendTxInitRbf { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendTxInitRbf event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendTxAckRbf { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendTxAckRbf event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendTxAbort { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendTxAbort event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendAnnouncementSignatures event in peer_handler for node {} for channel {})",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, ref update_fee, ref commitment_signed } } => {
+                                                       log_debug!(self.logger, "Handling UpdateHTLCs event in peer_handler for node {} with {} adds, {} fulfills, {} fails for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       update_add_htlcs.len(),
+                                                                       update_fulfill_htlcs.len(),
+                                                                       update_fail_htlcs.len(),
+                                                                       log_bytes!(commitment_signed.channel_id));
+                                                       let mut peer = get_peer_for_forwarding!(node_id);
+                                                       for msg in update_add_htlcs {
+                                                               self.enqueue_message(&mut *peer, msg);
+                                                       }
+                                                       for msg in update_fulfill_htlcs {
+                                                               self.enqueue_message(&mut *peer, msg);
+                                                       }
+                                                       for msg in update_fail_htlcs {
+                                                               self.enqueue_message(&mut *peer, msg);
+                                                       }
+                                                       for msg in update_fail_malformed_htlcs {
+                                                               self.enqueue_message(&mut *peer, msg);
+                                                       }
+                                                       if let &Some(ref msg) = update_fee {
+                                                               self.enqueue_message(&mut *peer, msg);
+                                                       }
+                                                       self.enqueue_message(&mut *peer, commitment_signed);
+                                               },
+                                               MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendRevokeAndACK event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendClosingSigned { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendClosingSigned event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendShutdown { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling Shutdown event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => {
+                                                       log_debug!(self.logger, "Handling SendChannelReestablish event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id),
+                                                                       log_bytes!(msg.channel_id));
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendChannelAnnouncement { ref node_id, ref msg, ref update_msg } => {
+                                                       log_debug!(self.logger, "Handling SendChannelAnnouncement event in peer_handler for node {} for short channel id {}",
+                                                                       log_pubkey!(node_id),
+                                                                       msg.contents.short_channel_id);
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), update_msg);
+                                               },
+                                               MessageSendEvent::BroadcastChannelAnnouncement { msg, update_msg } => {
+                                                       log_debug!(self.logger, "Handling BroadcastChannelAnnouncement event in peer_handler for short channel id {}", msg.contents.short_channel_id);
+                                                       match self.message_handler.route_handler.handle_channel_announcement(&msg) {
+                                                               Ok(_) | Err(LightningError { action: msgs::ErrorAction::IgnoreDuplicateGossip, .. }) =>
+                                                                       self.forward_broadcast_msg(peers, &wire::Message::ChannelAnnouncement(msg), None),
+                                                               _ => {},
+                                                       }
+                                                       if let Some(msg) = update_msg {
+                                                               match self.message_handler.route_handler.handle_channel_update(&msg) {
+                                                                       Ok(_) | Err(LightningError { action: msgs::ErrorAction::IgnoreDuplicateGossip, .. }) =>
+                                                                               self.forward_broadcast_msg(peers, &wire::Message::ChannelUpdate(msg), None),
+                                                                       _ => {},
+                                                               }
+                                                       }
+                                               },
+                                               MessageSendEvent::BroadcastChannelUpdate { msg } => {
+                                                       log_debug!(self.logger, "Handling BroadcastChannelUpdate event in peer_handler for short channel id {}", msg.contents.short_channel_id);
                                                        match self.message_handler.route_handler.handle_channel_update(&msg) {
                                                                Ok(_) | Err(LightningError { action: msgs::ErrorAction::IgnoreDuplicateGossip, .. }) =>
                                                                        self.forward_broadcast_msg(peers, &wire::Message::ChannelUpdate(msg), None),
                                                                _ => {},
                                                        }
+                                               },
+                                               MessageSendEvent::BroadcastNodeAnnouncement { msg } => {
+                                                       log_debug!(self.logger, "Handling BroadcastNodeAnnouncement event in peer_handler for node {}", msg.contents.node_id);
+                                                       match self.message_handler.route_handler.handle_node_announcement(&msg) {
+                                                               Ok(_) | Err(LightningError { action: msgs::ErrorAction::IgnoreDuplicateGossip, .. }) =>
+                                                                       self.forward_broadcast_msg(peers, &wire::Message::NodeAnnouncement(msg), None),
+                                                               _ => {},
+                                                       }
+                                               },
+                                               MessageSendEvent::SendChannelUpdate { ref node_id, ref msg } => {
+                                                       log_trace!(self.logger, "Handling SendChannelUpdate event in peer_handler for node {} for channel {}",
+                                                                       log_pubkey!(node_id), msg.contents.short_channel_id);
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::HandleError { node_id, action } => {
+                                                       match action {
+                                                               msgs::ErrorAction::DisconnectPeer { msg } => {
+                                                                       if let Some(msg) = msg.as_ref() {
+                                                                               log_trace!(self.logger, "Handling DisconnectPeer HandleError event in peer_handler for node {} with message {}",
+                                                                                       log_pubkey!(node_id), msg.data);
+                                                                       } else {
+                                                                               log_trace!(self.logger, "Handling DisconnectPeer HandleError event in peer_handler for node {}",
+                                                                                       log_pubkey!(node_id));
+                                                                       }
+                                                                       // We do not have the peers write lock, so we just store that we're
+                                                                       // about to disconenct the peer and do it after we finish
+                                                                       // processing most messages.
+                                                                       let msg = msg.map(|msg| wire::Message::<<<CMH as core::ops::Deref>::Target as wire::CustomMessageReader>::CustomMessage>::Error(msg));
+                                                                       peers_to_disconnect.insert(node_id, msg);
+                                                               },
+                                                               msgs::ErrorAction::DisconnectPeerWithWarning { msg } => {
+                                                                       log_trace!(self.logger, "Handling DisconnectPeer HandleError event in peer_handler for node {} with message {}",
+                                                                               log_pubkey!(node_id), msg.data);
+                                                                       // We do not have the peers write lock, so we just store that we're
+                                                                       // about to disconenct the peer and do it after we finish
+                                                                       // processing most messages.
+                                                                       peers_to_disconnect.insert(node_id, Some(wire::Message::Warning(msg)));
+                                                               },
+                                                               msgs::ErrorAction::IgnoreAndLog(level) => {
+                                                                       log_given_level!(self.logger, level, "Received a HandleError event to be ignored for node {}", log_pubkey!(node_id));
+                                                               },
+                                                               msgs::ErrorAction::IgnoreDuplicateGossip => {},
+                                                               msgs::ErrorAction::IgnoreError => {
+                                                                               log_debug!(self.logger, "Received a HandleError event to be ignored for node {}", log_pubkey!(node_id));
+                                                                       },
+                                                               msgs::ErrorAction::SendErrorMessage { ref msg } => {
+                                                                       log_trace!(self.logger, "Handling SendErrorMessage HandleError event in peer_handler for node {} with message {}",
+                                                                                       log_pubkey!(node_id),
+                                                                                       msg.data);
+                                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(&node_id), msg);
+                                                               },
+                                                               msgs::ErrorAction::SendWarningMessage { ref msg, ref log_level } => {
+                                                                       log_given_level!(self.logger, *log_level, "Handling SendWarningMessage HandleError event in peer_handler for node {} with message {}",
+                                                                                       log_pubkey!(node_id),
+                                                                                       msg.data);
+                                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(&node_id), msg);
+                                                               },
+                                                       }
+                                               },
+                                               MessageSendEvent::SendChannelRangeQuery { ref node_id, ref msg } => {
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
+                                               },
+                                               MessageSendEvent::SendShortIdsQuery { ref node_id, ref msg } => {
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
                                                }
-                                       },
-                                       MessageSendEvent::BroadcastChannelUpdate { msg } => {
-                                               log_debug!(self.logger, "Handling BroadcastChannelUpdate event in peer_handler for short channel id {}", msg.contents.short_channel_id);
-                                               match self.message_handler.route_handler.handle_channel_update(&msg) {
-                                                       Ok(_) | Err(LightningError { action: msgs::ErrorAction::IgnoreDuplicateGossip, .. }) =>
-                                                               self.forward_broadcast_msg(peers, &wire::Message::ChannelUpdate(msg), None),
-                                                       _ => {},
-                                               }
-                                       },
-                                       MessageSendEvent::BroadcastNodeAnnouncement { msg } => {
-                                               log_debug!(self.logger, "Handling BroadcastNodeAnnouncement event in peer_handler for node {}", msg.contents.node_id);
-                                               match self.message_handler.route_handler.handle_node_announcement(&msg) {
-                                                       Ok(_) | Err(LightningError { action: msgs::ErrorAction::IgnoreDuplicateGossip, .. }) =>
-                                                               self.forward_broadcast_msg(peers, &wire::Message::NodeAnnouncement(msg), None),
-                                                       _ => {},
+                                               MessageSendEvent::SendReplyChannelRange { ref node_id, ref msg } => {
+                                                       log_gossip!(self.logger, "Handling SendReplyChannelRange event in peer_handler for node {} with num_scids={} first_blocknum={} number_of_blocks={}, sync_complete={}",
+                                                               log_pubkey!(node_id),
+                                                               msg.short_channel_ids.len(),
+                                                               msg.first_blocknum,
+                                                               msg.number_of_blocks,
+                                                               msg.sync_complete);
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
                                                }
-                                       },
-                                       MessageSendEvent::SendChannelUpdate { ref node_id, ref msg } => {
-                                               log_trace!(self.logger, "Handling SendChannelUpdate event in peer_handler for node {} for channel {}",
-                                                               log_pubkey!(node_id), msg.contents.short_channel_id);
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       },
-                                       MessageSendEvent::HandleError { ref node_id, ref action } => {
-                                               match *action {
-                                                       msgs::ErrorAction::DisconnectPeer { ref msg } => {
-                                                               // We do not have the peers write lock, so we just store that we're
-                                                               // about to disconenct the peer and do it after we finish
-                                                               // processing most messages.
-                                                               peers_to_disconnect.insert(*node_id, msg.clone());
-                                                       },
-                                                       msgs::ErrorAction::IgnoreAndLog(level) => {
-                                                               log_given_level!(self.logger, level, "Received a HandleError event to be ignored for node {}", log_pubkey!(node_id));
-                                                       },
-                                                       msgs::ErrorAction::IgnoreDuplicateGossip => {},
-                                                       msgs::ErrorAction::IgnoreError => {
-                                                               log_debug!(self.logger, "Received a HandleError event to be ignored for node {}", log_pubkey!(node_id));
-                                                       },
-                                                       msgs::ErrorAction::SendErrorMessage { ref msg } => {
-                                                               log_trace!(self.logger, "Handling SendErrorMessage HandleError event in peer_handler for node {} with message {}",
-                                                                               log_pubkey!(node_id),
-                                                                               msg.data);
-                                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                                       },
-                                                       msgs::ErrorAction::SendWarningMessage { ref msg, ref log_level } => {
-                                                               log_given_level!(self.logger, *log_level, "Handling SendWarningMessage HandleError event in peer_handler for node {} with message {}",
-                                                                               log_pubkey!(node_id),
-                                                                               msg.data);
-                                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                                       },
+                                               MessageSendEvent::SendGossipTimestampFilter { ref node_id, ref msg } => {
+                                                       self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
                                                }
-                                       },
-                                       MessageSendEvent::SendChannelRangeQuery { ref node_id, ref msg } => {
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       },
-                                       MessageSendEvent::SendShortIdsQuery { ref node_id, ref msg } => {
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       }
-                                       MessageSendEvent::SendReplyChannelRange { ref node_id, ref msg } => {
-                                               log_gossip!(self.logger, "Handling SendReplyChannelRange event in peer_handler for node {} with num_scids={} first_blocknum={} number_of_blocks={}, sync_complete={}",
-                                                       log_pubkey!(node_id),
-                                                       msg.short_channel_ids.len(),
-                                                       msg.first_blocknum,
-                                                       msg.number_of_blocks,
-                                                       msg.sync_complete);
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
-                                       }
-                                       MessageSendEvent::SendGossipTimestampFilter { ref node_id, ref msg } => {
-                                               self.enqueue_message(&mut *get_peer_for_forwarding!(node_id), msg);
                                        }
                                }
-                       }
 
-                       for (node_id, msg) in self.custom_message_handler.get_and_clear_pending_msg() {
-                               if peers_to_disconnect.get(&node_id).is_some() { continue; }
-                               self.enqueue_message(&mut *get_peer_for_forwarding!(&node_id), &msg);
-                       }
+                               for (node_id, msg) in self.message_handler.custom_message_handler.get_and_clear_pending_msg() {
+                                       if peers_to_disconnect.get(&node_id).is_some() { continue; }
+                                       self.enqueue_message(&mut *get_peer_for_forwarding!(&node_id), &msg);
+                               }
 
-                       for (descriptor, peer_mutex) in peers.iter() {
-                               let mut peer = peer_mutex.lock().unwrap();
-                               if flush_read_disabled { peer.received_channel_announce_since_backlogged = false; }
-                               self.do_attempt_write_data(&mut (*descriptor).clone(), &mut *peer, flush_read_disabled);
+                               for (descriptor, peer_mutex) in peers.iter() {
+                                       let mut peer = peer_mutex.lock().unwrap();
+                                       if flush_read_disabled { peer.received_channel_announce_since_backlogged = false; }
+                                       self.do_attempt_write_data(&mut (*descriptor).clone(), &mut *peer, flush_read_disabled);
+                               }
                        }
-               }
-               if !peers_to_disconnect.is_empty() {
-                       let mut peers_lock = self.peers.write().unwrap();
-                       let peers = &mut *peers_lock;
-                       for (node_id, msg) in peers_to_disconnect.drain() {
-                               // Note that since we are holding the peers *write* lock we can
-                               // remove from node_id_to_descriptor immediately (as no other
-                               // thread can be holding the peer lock if we have the global write
-                               // lock).
-
-                               let descriptor_opt = self.node_id_to_descriptor.lock().unwrap().remove(&node_id);
-                               if let Some(mut descriptor) = descriptor_opt {
-                                       if let Some(peer_mutex) = peers.remove(&descriptor) {
-                                               let mut peer = peer_mutex.lock().unwrap();
-                                               if let Some(msg) = msg {
-                                                       log_trace!(self.logger, "Handling DisconnectPeer HandleError event in peer_handler for node {} with message {}",
-                                                                       log_pubkey!(node_id),
-                                                                       msg.data);
-                                                       self.enqueue_message(&mut *peer, &msg);
-                                                       // This isn't guaranteed to work, but if there is enough free
-                                                       // room in the send buffer, put the error message there...
-                                                       self.do_attempt_write_data(&mut descriptor, &mut *peer, false);
-                                               }
-                                               self.do_disconnect(descriptor, &*peer, "DisconnectPeer HandleError");
-                                       } else { debug_assert!(false, "Missing connection for peer"); }
+                       if !peers_to_disconnect.is_empty() {
+                               let mut peers_lock = self.peers.write().unwrap();
+                               let peers = &mut *peers_lock;
+                               for (node_id, msg) in peers_to_disconnect.drain() {
+                                       // Note that since we are holding the peers *write* lock we can
+                                       // remove from node_id_to_descriptor immediately (as no other
+                                       // thread can be holding the peer lock if we have the global write
+                                       // lock).
+
+                                       let descriptor_opt = self.node_id_to_descriptor.lock().unwrap().remove(&node_id);
+                                       if let Some(mut descriptor) = descriptor_opt {
+                                               if let Some(peer_mutex) = peers.remove(&descriptor) {
+                                                       let mut peer = peer_mutex.lock().unwrap();
+                                                       if let Some(msg) = msg {
+                                                               self.enqueue_message(&mut *peer, &msg);
+                                                               // This isn't guaranteed to work, but if there is enough free
+                                                               // room in the send buffer, put the error message there...
+                                                               self.do_attempt_write_data(&mut descriptor, &mut *peer, false);
+                                                       }
+                                                       self.do_disconnect(descriptor, &*peer, "DisconnectPeer HandleError");
+                                               } else { debug_assert!(false, "Missing connection for peer"); }
+                                       }
                                }
                        }
+
+                       if self.event_processing_state.fetch_sub(1, Ordering::AcqRel) != 1 {
+                               // If another thread incremented the state while we were running we should go
+                               // around again, but only once.
+                               self.event_processing_state.store(1, Ordering::Release);
+                               continue;
+                       }
+                       break;
                }
        }
 
@@ -2103,7 +2386,7 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                                                if let Some((node_id, _)) = peer.their_node_id {
                                                        self.node_id_to_descriptor.lock().unwrap().remove(&node_id);
                                                }
-                                               self.do_disconnect(descriptor, &*peer, "ping timeout");
+                                               self.do_disconnect(descriptor, &*peer, "ping/handshake timeout");
                                        }
                                }
                        }
@@ -2147,13 +2430,16 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
                addresses.sort_by_key(|addr| addr.get_id());
 
                let features = self.message_handler.chan_handler.provided_node_features()
-                       .or(self.message_handler.route_handler.provided_node_features())
-                       .or(self.message_handler.onion_message_handler.provided_node_features());
+                       | self.message_handler.route_handler.provided_node_features()
+                       | self.message_handler.onion_message_handler.provided_node_features()
+                       | self.message_handler.custom_message_handler.provided_node_features();
                let announcement = msgs::UnsignedNodeAnnouncement {
                        features,
                        timestamp: self.last_node_announcement_serial.fetch_add(1, Ordering::AcqRel),
                        node_id: NodeId::from_pubkey(&self.node_signer.get_node_id(Recipient::Node).unwrap()),
-                       rgb, alias, addresses,
+                       rgb,
+                       alias: NodeAlias(alias),
+                       addresses,
                        excess_address_data: Vec::new(),
                        excess_data: Vec::new(),
                };
@@ -2193,18 +2479,23 @@ fn is_gossip_msg(type_id: u16) -> bool {
 
 #[cfg(test)]
 mod tests {
-       use crate::chain::keysinterface::{NodeSigner, Recipient};
+       use crate::sign::{NodeSigner, Recipient};
+       use crate::events;
+       use crate::io;
+       use crate::ln::features::{InitFeatures, NodeFeatures};
        use crate::ln::peer_channel_encryptor::PeerChannelEncryptor;
-       use crate::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler, filter_addresses};
+       use crate::ln::peer_handler::{CustomMessageHandler, PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler, filter_addresses};
        use crate::ln::{msgs, wire};
-       use crate::ln::msgs::NetAddress;
-       use crate::util::events;
+       use crate::ln::msgs::{LightningError, NetAddress};
        use crate::util::test_utils;
 
-       use bitcoin::secp256k1::SecretKey;
+       use bitcoin::Network;
+       use bitcoin::blockdata::constants::ChainHash;
+       use bitcoin::secp256k1::{PublicKey, SecretKey};
 
        use crate::prelude::*;
        use crate::sync::{Arc, Mutex};
+       use core::convert::Infallible;
        use core::sync::atomic::{AtomicBool, Ordering};
 
        #[derive(Clone)]
@@ -2237,19 +2528,51 @@ mod tests {
        struct PeerManagerCfg {
                chan_handler: test_utils::TestChannelMessageHandler,
                routing_handler: test_utils::TestRoutingMessageHandler,
+               custom_handler: TestCustomMessageHandler,
                logger: test_utils::TestLogger,
                node_signer: test_utils::TestNodeSigner,
        }
 
+       struct TestCustomMessageHandler {
+               features: InitFeatures,
+       }
+
+       impl wire::CustomMessageReader for TestCustomMessageHandler {
+               type CustomMessage = Infallible;
+               fn read<R: io::Read>(&self, _: u16, _: &mut R) -> Result<Option<Self::CustomMessage>, msgs::DecodeError> {
+                       Ok(None)
+               }
+       }
+
+       impl CustomMessageHandler for TestCustomMessageHandler {
+               fn handle_custom_message(&self, _: Infallible, _: &PublicKey) -> Result<(), LightningError> {
+                       unreachable!();
+               }
+
+               fn get_and_clear_pending_msg(&self) -> Vec<(PublicKey, Self::CustomMessage)> { Vec::new() }
+
+               fn provided_node_features(&self) -> NodeFeatures { NodeFeatures::empty() }
+
+               fn provided_init_features(&self, _: &PublicKey) -> InitFeatures {
+                       self.features.clone()
+               }
+       }
+
        fn create_peermgr_cfgs(peer_count: usize) -> Vec<PeerManagerCfg> {
                let mut cfgs = Vec::new();
                for i in 0..peer_count {
                        let node_secret = SecretKey::from_slice(&[42 + i as u8; 32]).unwrap();
+                       let features = {
+                               let mut feature_bits = vec![0u8; 33];
+                               feature_bits[32] = 0b00000001;
+                               InitFeatures::from_le_bytes(feature_bits)
+                       };
                        cfgs.push(
                                PeerManagerCfg{
-                                       chan_handler: test_utils::TestChannelMessageHandler::new(),
+                                       chan_handler: test_utils::TestChannelMessageHandler::new(ChainHash::using_genesis_block(Network::Testnet)),
                                        logger: test_utils::TestLogger::new(),
                                        routing_handler: test_utils::TestRoutingMessageHandler::new(),
+                                       custom_handler: TestCustomMessageHandler { features },
                                        node_signer: test_utils::TestNodeSigner::new(node_secret),
                                }
                        );
@@ -2258,19 +2581,65 @@ mod tests {
                cfgs
        }
 
-       fn create_network<'a>(peer_count: usize, cfgs: &'a Vec<PeerManagerCfg>) -> Vec<PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler, &'a test_utils::TestRoutingMessageHandler, IgnoringMessageHandler, &'a test_utils::TestLogger, IgnoringMessageHandler, &'a test_utils::TestNodeSigner>> {
+       fn create_feature_incompatible_peermgr_cfgs(peer_count: usize) -> Vec<PeerManagerCfg> {
+               let mut cfgs = Vec::new();
+               for i in 0..peer_count {
+                       let node_secret = SecretKey::from_slice(&[42 + i as u8; 32]).unwrap();
+                       let features = {
+                               let mut feature_bits = vec![0u8; 33 + i + 1];
+                               feature_bits[33 + i] = 0b00000001;
+                               InitFeatures::from_le_bytes(feature_bits)
+                       };
+                       cfgs.push(
+                               PeerManagerCfg{
+                                       chan_handler: test_utils::TestChannelMessageHandler::new(ChainHash::using_genesis_block(Network::Testnet)),
+                                       logger: test_utils::TestLogger::new(),
+                                       routing_handler: test_utils::TestRoutingMessageHandler::new(),
+                                       custom_handler: TestCustomMessageHandler { features },
+                                       node_signer: test_utils::TestNodeSigner::new(node_secret),
+                               }
+                       );
+               }
+
+               cfgs
+       }
+
+       fn create_chain_incompatible_peermgr_cfgs(peer_count: usize) -> Vec<PeerManagerCfg> {
+               let mut cfgs = Vec::new();
+               for i in 0..peer_count {
+                       let node_secret = SecretKey::from_slice(&[42 + i as u8; 32]).unwrap();
+                       let features = InitFeatures::from_le_bytes(vec![0u8; 33]);
+                       let network = ChainHash::from(&[i as u8; 32][..]);
+                       cfgs.push(
+                               PeerManagerCfg{
+                                       chan_handler: test_utils::TestChannelMessageHandler::new(network),
+                                       logger: test_utils::TestLogger::new(),
+                                       routing_handler: test_utils::TestRoutingMessageHandler::new(),
+                                       custom_handler: TestCustomMessageHandler { features },
+                                       node_signer: test_utils::TestNodeSigner::new(node_secret),
+                               }
+                       );
+               }
+
+               cfgs
+       }
+
+       fn create_network<'a>(peer_count: usize, cfgs: &'a Vec<PeerManagerCfg>) -> Vec<PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler, &'a test_utils::TestRoutingMessageHandler, IgnoringMessageHandler, &'a test_utils::TestLogger, &'a TestCustomMessageHandler, &'a test_utils::TestNodeSigner>> {
                let mut peers = Vec::new();
                for i in 0..peer_count {
                        let ephemeral_bytes = [i as u8; 32];
-                       let msg_handler = MessageHandler { chan_handler: &cfgs[i].chan_handler, route_handler: &cfgs[i].routing_handler, onion_message_handler: IgnoringMessageHandler {} };
-                       let peer = PeerManager::new(msg_handler, 0, &ephemeral_bytes, &cfgs[i].logger, IgnoringMessageHandler {}, &cfgs[i].node_signer);
+                       let msg_handler = MessageHandler {
+                               chan_handler: &cfgs[i].chan_handler, route_handler: &cfgs[i].routing_handler,
+                               onion_message_handler: IgnoringMessageHandler {}, custom_message_handler: &cfgs[i].custom_handler
+                       };
+                       let peer = PeerManager::new(msg_handler, 0, &ephemeral_bytes, &cfgs[i].logger, &cfgs[i].node_signer);
                        peers.push(peer);
                }
 
                peers
        }
 
-       fn establish_connection<'a>(peer_a: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler, &'a test_utils::TestRoutingMessageHandler, IgnoringMessageHandler, &'a test_utils::TestLogger, IgnoringMessageHandler, &'a test_utils::TestNodeSigner>, peer_b: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler, &'a test_utils::TestRoutingMessageHandler, IgnoringMessageHandler, &'a test_utils::TestLogger, IgnoringMessageHandler, &'a test_utils::TestNodeSigner>) -> (FileDescriptor, FileDescriptor) {
+       fn establish_connection<'a>(peer_a: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler, &'a test_utils::TestRoutingMessageHandler, IgnoringMessageHandler, &'a test_utils::TestLogger, &'a TestCustomMessageHandler, &'a test_utils::TestNodeSigner>, peer_b: &PeerManager<FileDescriptor, &'a test_utils::TestChannelMessageHandler, &'a test_utils::TestRoutingMessageHandler, IgnoringMessageHandler, &'a test_utils::TestLogger, &'a TestCustomMessageHandler, &'a test_utils::TestNodeSigner>) -> (FileDescriptor, FileDescriptor) {
                let id_a = peer_a.node_signer.get_node_id(Recipient::Node).unwrap();
                let mut fd_a = FileDescriptor {
                        fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())),
@@ -2349,7 +2718,7 @@ mod tests {
                                                if peers[0].read_event(&mut fd_a, &b_data).is_err() { break; }
 
                                                cfgs[0].chan_handler.pending_events.lock().unwrap()
-                                                       .push(crate::util::events::MessageSendEvent::SendShutdown {
+                                                       .push(crate::events::MessageSendEvent::SendShutdown {
                                                                node_id: peers[1].node_signer.get_node_id(Recipient::Node).unwrap(),
                                                                msg: msgs::Shutdown {
                                                                        channel_id: [0; 32],
@@ -2357,7 +2726,7 @@ mod tests {
                                                                },
                                                        });
                                                cfgs[1].chan_handler.pending_events.lock().unwrap()
-                                                       .push(crate::util::events::MessageSendEvent::SendShutdown {
+                                                       .push(crate::events::MessageSendEvent::SendShutdown {
                                                                node_id: peers[0].node_signer.get_node_id(Recipient::Node).unwrap(),
                                                                msg: msgs::Shutdown {
                                                                        channel_id: [0; 32],
@@ -2385,6 +2754,78 @@ mod tests {
                thrd_b.join().unwrap();
        }
 
+       #[test]
+       fn test_feature_incompatible_peers() {
+               let cfgs = create_peermgr_cfgs(2);
+               let incompatible_cfgs = create_feature_incompatible_peermgr_cfgs(2);
+
+               let peers = create_network(2, &cfgs);
+               let incompatible_peers = create_network(2, &incompatible_cfgs);
+               let peer_pairs = [(&peers[0], &incompatible_peers[0]), (&incompatible_peers[1], &peers[1])];
+               for (peer_a, peer_b) in peer_pairs.iter() {
+                       let id_a = peer_a.node_signer.get_node_id(Recipient::Node).unwrap();
+                       let mut fd_a = FileDescriptor {
+                               fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())),
+                               disconnect: Arc::new(AtomicBool::new(false)),
+                       };
+                       let addr_a = NetAddress::IPv4{addr: [127, 0, 0, 1], port: 1000};
+                       let mut fd_b = FileDescriptor {
+                               fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())),
+                               disconnect: Arc::new(AtomicBool::new(false)),
+                       };
+                       let addr_b = NetAddress::IPv4{addr: [127, 0, 0, 1], port: 1001};
+                       let initial_data = peer_b.new_outbound_connection(id_a, fd_b.clone(), Some(addr_a.clone())).unwrap();
+                       peer_a.new_inbound_connection(fd_a.clone(), Some(addr_b.clone())).unwrap();
+                       assert_eq!(peer_a.read_event(&mut fd_a, &initial_data).unwrap(), false);
+                       peer_a.process_events();
+
+                       let a_data = fd_a.outbound_data.lock().unwrap().split_off(0);
+                       assert_eq!(peer_b.read_event(&mut fd_b, &a_data).unwrap(), false);
+
+                       peer_b.process_events();
+                       let b_data = fd_b.outbound_data.lock().unwrap().split_off(0);
+
+                       // Should fail because of unknown required features
+                       assert!(peer_a.read_event(&mut fd_a, &b_data).is_err());
+               }
+       }
+
+       #[test]
+       fn test_chain_incompatible_peers() {
+               let cfgs = create_peermgr_cfgs(2);
+               let incompatible_cfgs = create_chain_incompatible_peermgr_cfgs(2);
+
+               let peers = create_network(2, &cfgs);
+               let incompatible_peers = create_network(2, &incompatible_cfgs);
+               let peer_pairs = [(&peers[0], &incompatible_peers[0]), (&incompatible_peers[1], &peers[1])];
+               for (peer_a, peer_b) in peer_pairs.iter() {
+                       let id_a = peer_a.node_signer.get_node_id(Recipient::Node).unwrap();
+                       let mut fd_a = FileDescriptor {
+                               fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())),
+                               disconnect: Arc::new(AtomicBool::new(false)),
+                       };
+                       let addr_a = NetAddress::IPv4{addr: [127, 0, 0, 1], port: 1000};
+                       let mut fd_b = FileDescriptor {
+                               fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())),
+                               disconnect: Arc::new(AtomicBool::new(false)),
+                       };
+                       let addr_b = NetAddress::IPv4{addr: [127, 0, 0, 1], port: 1001};
+                       let initial_data = peer_b.new_outbound_connection(id_a, fd_b.clone(), Some(addr_a.clone())).unwrap();
+                       peer_a.new_inbound_connection(fd_a.clone(), Some(addr_b.clone())).unwrap();
+                       assert_eq!(peer_a.read_event(&mut fd_a, &initial_data).unwrap(), false);
+                       peer_a.process_events();
+
+                       let a_data = fd_a.outbound_data.lock().unwrap().split_off(0);
+                       assert_eq!(peer_b.read_event(&mut fd_b, &a_data).unwrap(), false);
+
+                       peer_b.process_events();
+                       let b_data = fd_b.outbound_data.lock().unwrap().split_off(0);
+
+                       // Should fail because of incompatible chains
+                       assert!(peer_a.read_event(&mut fd_a, &b_data).is_err());
+               }
+       }
+
        #[test]
        fn test_disconnect_peer() {
                // Simple test which builds a network of PeerManager, connects and brings them to NoiseState::Finished and
@@ -2409,8 +2850,8 @@ mod tests {
                // Simple test which builds a network of PeerManager, connects and brings them to NoiseState::Finished and
                // push a message from one peer to another.
                let cfgs = create_peermgr_cfgs(2);
-               let a_chan_handler = test_utils::TestChannelMessageHandler::new();
-               let b_chan_handler = test_utils::TestChannelMessageHandler::new();
+               let a_chan_handler = test_utils::TestChannelMessageHandler::new(ChainHash::using_genesis_block(Network::Testnet));
+               let b_chan_handler = test_utils::TestChannelMessageHandler::new(ChainHash::using_genesis_block(Network::Testnet));
                let mut peers = create_network(2, &cfgs);
                let (fd_a, mut fd_b) = establish_connection(&peers[0], &peers[1]);
                assert_eq!(peers[0].peers.read().unwrap().len(), 1);
@@ -2673,4 +3114,53 @@ mod tests {
                // For (None)
                assert_eq!(filter_addresses(None), None);
        }
+
+       #[test]
+       #[cfg(feature = "std")]
+       fn test_process_events_multithreaded() {
+               use std::time::{Duration, Instant};
+               // Test that `process_events` getting called on multiple threads doesn't generate too many
+               // loop iterations.
+               // Each time `process_events` goes around the loop we call
+               // `get_and_clear_pending_msg_events`, which we count using the `TestMessageHandler`.
+               // Because the loop should go around once more after a call which fails to take the
+               // single-threaded lock, if we write zero to the counter before calling `process_events` we
+               // should never observe there having been more than 2 loop iterations.
+               // Further, because the last thread to exit will call `process_events` before returning, we
+               // should always have at least one count at the end.
+               let cfg = Arc::new(create_peermgr_cfgs(1));
+               // Until we have std::thread::scoped we have to unsafe { turn off the borrow checker }.
+               let peer = Arc::new(create_network(1, unsafe { &*(&*cfg as *const _) as &'static _ }).pop().unwrap());
+
+               let exit_flag = Arc::new(AtomicBool::new(false));
+               macro_rules! spawn_thread { () => { {
+                       let thread_cfg = Arc::clone(&cfg);
+                       let thread_peer = Arc::clone(&peer);
+                       let thread_exit = Arc::clone(&exit_flag);
+                       std::thread::spawn(move || {
+                               while !thread_exit.load(Ordering::Acquire) {
+                                       thread_cfg[0].chan_handler.message_fetch_counter.store(0, Ordering::Release);
+                                       thread_peer.process_events();
+                                       std::thread::sleep(Duration::from_micros(1));
+                               }
+                       })
+               } } }
+
+               let thread_a = spawn_thread!();
+               let thread_b = spawn_thread!();
+               let thread_c = spawn_thread!();
+
+               let start_time = Instant::now();
+               while start_time.elapsed() < Duration::from_millis(100) {
+                       let val = cfg[0].chan_handler.message_fetch_counter.load(Ordering::Acquire);
+                       assert!(val <= 2);
+                       std::thread::yield_now(); // Winblowz seemingly doesn't ever interrupt threads?!
+               }
+
+               exit_flag.store(true, Ordering::Release);
+               thread_a.join().unwrap();
+               thread_b.join().unwrap();
+               thread_c.join().unwrap();
+               assert!(cfg[0].chan_handler.message_fetch_counter.load(Ordering::Acquire) >= 1);
+       }
 }