Collect all lightning std::sync imports under crate::sync
[rust-lightning] / lightning / src / ln / peer_handler.rs
index b5e5ebef2cb53d0eea812474764ac45d96950c44..0ec24fbf84c3ad31bfdf32bff421ffa310b9873d 100644 (file)
@@ -30,25 +30,146 @@ use util::events::{MessageSendEvent, MessageSendEventsProvider};
 use util::logger::Logger;
 use routing::network_graph::NetGraphMsgHandler;
 
-use std::collections::{HashMap,hash_map,HashSet,LinkedList};
-use std::sync::{Arc, Mutex};
-use std::sync::atomic::{AtomicUsize, Ordering};
-use std::{cmp,error,hash,fmt};
-use std::ops::Deref;
+use prelude::*;
+use alloc::collections::LinkedList;
+use alloc::fmt::Debug;
+use sync::{Arc, Mutex};
+use core::sync::atomic::{AtomicUsize, Ordering};
+use core::{cmp, hash, fmt, mem};
+use core::ops::Deref;
+use std::error;
 
 use bitcoin::hashes::sha256::Hash as Sha256;
 use bitcoin::hashes::sha256::HashEngine as Sha256Engine;
 use bitcoin::hashes::{HashEngine, Hash};
 
+/// A dummy struct which implements `RoutingMessageHandler` without storing any routing information
+/// or doing any processing. You can provide one of these as the route_handler in a MessageHandler.
+pub struct IgnoringMessageHandler{}
+impl MessageSendEventsProvider for IgnoringMessageHandler {
+       fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent> { Vec::new() }
+}
+impl RoutingMessageHandler for IgnoringMessageHandler {
+       fn handle_node_announcement(&self, _msg: &msgs::NodeAnnouncement) -> Result<bool, LightningError> { Ok(false) }
+       fn handle_channel_announcement(&self, _msg: &msgs::ChannelAnnouncement) -> Result<bool, LightningError> { Ok(false) }
+       fn handle_channel_update(&self, _msg: &msgs::ChannelUpdate) -> Result<bool, LightningError> { Ok(false) }
+       fn handle_htlc_fail_channel_update(&self, _update: &msgs::HTLCFailChannelUpdate) {}
+       fn get_next_channel_announcements(&self, _starting_point: u64, _batch_amount: u8) ->
+               Vec<(msgs::ChannelAnnouncement, Option<msgs::ChannelUpdate>, Option<msgs::ChannelUpdate>)> { Vec::new() }
+       fn get_next_node_announcements(&self, _starting_point: Option<&PublicKey>, _batch_amount: u8) -> Vec<msgs::NodeAnnouncement> { Vec::new() }
+       fn sync_routing_table(&self, _their_node_id: &PublicKey, _init: &msgs::Init) {}
+       fn handle_reply_channel_range(&self, _their_node_id: &PublicKey, _msg: msgs::ReplyChannelRange) -> Result<(), LightningError> { Ok(()) }
+       fn handle_reply_short_channel_ids_end(&self, _their_node_id: &PublicKey, _msg: msgs::ReplyShortChannelIdsEnd) -> Result<(), LightningError> { Ok(()) }
+       fn handle_query_channel_range(&self, _their_node_id: &PublicKey, _msg: msgs::QueryChannelRange) -> Result<(), LightningError> { Ok(()) }
+       fn handle_query_short_channel_ids(&self, _their_node_id: &PublicKey, _msg: msgs::QueryShortChannelIds) -> Result<(), LightningError> { Ok(()) }
+}
+impl Deref for IgnoringMessageHandler {
+       type Target = IgnoringMessageHandler;
+       fn deref(&self) -> &Self { self }
+}
+
+/// A dummy struct which implements `ChannelMessageHandler` without having any channels.
+/// You can provide one of these as the route_handler in a MessageHandler.
+pub struct ErroringMessageHandler {
+       message_queue: Mutex<Vec<MessageSendEvent>>
+}
+impl ErroringMessageHandler {
+       /// Constructs a new ErroringMessageHandler
+       pub fn new() -> Self {
+               Self { message_queue: Mutex::new(Vec::new()) }
+       }
+       fn push_error(&self, node_id: &PublicKey, channel_id: [u8; 32]) {
+               self.message_queue.lock().unwrap().push(MessageSendEvent::HandleError {
+                       action: msgs::ErrorAction::SendErrorMessage {
+                               msg: msgs::ErrorMessage { channel_id, data: "We do not support channel messages, sorry.".to_owned() },
+                       },
+                       node_id: node_id.clone(),
+               });
+       }
+}
+impl MessageSendEventsProvider for ErroringMessageHandler {
+       fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent> {
+               let mut res = Vec::new();
+               mem::swap(&mut res, &mut self.message_queue.lock().unwrap());
+               res
+       }
+}
+impl ChannelMessageHandler for ErroringMessageHandler {
+       // Any messages which are related to a specific channel generate an error message to let the
+       // peer know we don't care about channels.
+       fn handle_open_channel(&self, their_node_id: &PublicKey, _their_features: InitFeatures, msg: &msgs::OpenChannel) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.temporary_channel_id);
+       }
+       fn handle_accept_channel(&self, their_node_id: &PublicKey, _their_features: InitFeatures, msg: &msgs::AcceptChannel) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.temporary_channel_id);
+       }
+       fn handle_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.temporary_channel_id);
+       }
+       fn handle_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       fn handle_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       fn handle_shutdown(&self, their_node_id: &PublicKey, _their_features: &InitFeatures, msg: &msgs::Shutdown) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       fn handle_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       fn handle_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       fn handle_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       fn handle_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       fn handle_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       fn handle_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       fn handle_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       fn handle_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       fn handle_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       fn handle_channel_reestablish(&self, their_node_id: &PublicKey, msg: &msgs::ChannelReestablish) {
+               ErroringMessageHandler::push_error(self, their_node_id, msg.channel_id);
+       }
+       // msgs::ChannelUpdate does not contain the channel_id field, so we just drop them.
+       fn handle_channel_update(&self, _their_node_id: &PublicKey, _msg: &msgs::ChannelUpdate) {}
+       fn peer_disconnected(&self, _their_node_id: &PublicKey, _no_connection_possible: bool) {}
+       fn peer_connected(&self, _their_node_id: &PublicKey, _msg: &msgs::Init) {}
+       fn handle_error(&self, _their_node_id: &PublicKey, _msg: &msgs::ErrorMessage) {}
+}
+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> where
                CM::Target: ChannelMessageHandler,
                RM::Target: RoutingMessageHandler {
        /// A message handler which handles messages specific to channels. Usually this is just a
-       /// ChannelManager object.
+       /// [`ChannelManager`] object or an [`ErroringMessageHandler`].
+       ///
+       /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
        pub chan_handler: CM,
        /// A message handler which handles messages updating our knowledge of the network channel
-       /// graph. Usually this is just a NetGraphMsgHandlerMonitor object.
+       /// graph. Usually this is just a [`NetGraphMsgHandler`] object or an
+       /// [`IgnoringMessageHandler`].
+       ///
+       /// [`NetGraphMsgHandler`]: crate::routing::network_graph::NetGraphMsgHandler
        pub route_handler: RM,
 }
 
@@ -58,32 +179,35 @@ pub struct MessageHandler<CM: Deref, RM: Deref> where
 ///
 /// For efficiency, Clone should be relatively cheap for this type.
 ///
-/// You probably want to just extend an int and put a file descriptor in a struct and implement
-/// send_data. Note that if you are using a higher-level net library that may call close() itself,
-/// be careful to ensure you don't have races whereby you might register a new connection with an
-/// fd which is the same as a previous one which has yet to be removed via
-/// PeerManager::socket_disconnected().
+/// Two descriptors may compare equal (by [`cmp::Eq`] and [`hash::Hash`]) as long as the original
+/// has been disconnected, the [`PeerManager`] has been informed of the disconnection (either by it
+/// having triggered the disconnection or a call to [`PeerManager::socket_disconnected`]), and no
+/// further calls to the [`PeerManager`] related to the original socket occur. This allows you to
+/// use a file descriptor for your SocketDescriptor directly, however for simplicity you may wish
+/// to simply use another value which is guaranteed to be globally unique instead.
 pub trait SocketDescriptor : cmp::Eq + hash::Hash + Clone {
        /// Attempts to send some data from the given slice to the peer.
        ///
        /// Returns the amount of data which was sent, possibly 0 if the socket has since disconnected.
-       /// Note that in the disconnected case, socket_disconnected must still fire and further write
-       /// attempts may occur until that time.
+       /// Note that in the disconnected case, [`PeerManager::socket_disconnected`] must still be
+       /// called and further write attempts may occur until that time.
        ///
-       /// If the returned size is smaller than data.len(), a write_available event must
-       /// trigger the next time more data can be written. Additionally, until the a send_data event
-       /// completes fully, no further read_events should trigger on the same peer!
+       /// If the returned size is smaller than `data.len()`, a
+       /// [`PeerManager::write_buffer_space_avail`] call must be made the next time more data can be
+       /// written. Additionally, until a `send_data` event completes fully, no further
+       /// [`PeerManager::read_event`] calls should be made for the same peer! Because this is to
+       /// prevent denial-of-service issues, you should not read or buffer any data from the socket
+       /// until then.
        ///
-       /// If a read_event on this descriptor had previously returned true (indicating that read
-       /// events should be paused to prevent DoS in the send buffer), resume_read may be set
-       /// indicating that read events on this descriptor should resume. A resume_read of false does
-       /// *not* imply that further read events should be paused.
+       /// If a [`PeerManager::read_event`] call on this descriptor had previously returned true
+       /// (indicating that read events should be paused to prevent DoS in the send buffer),
+       /// `resume_read` may be set indicating that read events on this descriptor should resume. A
+       /// `resume_read` of false carries no meaning, and should not cause any action.
        fn send_data(&mut self, data: &[u8], resume_read: bool) -> usize;
-       /// Disconnect the socket pointed to by this SocketDescriptor. Once this function returns, no
-       /// more calls to write_buffer_space_avail, read_event or socket_disconnected may be made with
-       /// this descriptor. No socket_disconnected call should be generated as a result of this call,
-       /// though races may occur whereby disconnect_socket is called after a call to
-       /// socket_disconnected but prior to socket_disconnected returning.
+       /// Disconnect the socket pointed to by this SocketDescriptor.
+       ///
+       /// You do *not* need to call [`PeerManager::socket_disconnected`] with this socket after this
+       /// call (doing so is a noop).
        fn disconnect_socket(&mut self);
 }
 
@@ -118,9 +242,17 @@ enum InitSyncTracker{
        NodesSyncing(PublicKey),
 }
 
+/// When the outbound buffer has this many messages, we'll stop reading bytes from the peer until
+/// we have fewer than this many messages in the outbound buffer again.
+/// We also use this as the target number of outbound gossip messages to keep in the write buffer,
+/// refilled as we send bytes.
+const OUTBOUND_BUFFER_LIMIT_READ_PAUSE: usize = 10;
+/// When the outbound buffer has this many messages, we'll simply skip relaying gossip messages to
+/// the peer.
+const OUTBOUND_BUFFER_LIMIT_DROP_GOSSIP: usize = 20;
+
 struct Peer {
        channel_encryptor: PeerChannelEncryptor,
-       outbound: bool,
        their_node_id: Option<PublicKey>,
        their_features: Option<InitFeatures>,
 
@@ -164,9 +296,6 @@ impl Peer {
 
 struct PeerHolder<Descriptor: SocketDescriptor> {
        peers: HashMap<Descriptor, Peer>,
-       /// Added to by do_read_event for cases where we pushed a message onto the send buffer but
-       /// didn't call do_attempt_write_data to avoid reentrancy. Cleared in process_events()
-       peers_needing_send: HashSet<Descriptor>,
        /// Only add to this set when noise completes:
        node_id_to_descriptor: HashMap<PublicKey, Descriptor>,
 }
@@ -182,7 +311,7 @@ fn _check_usize_is_32_or_64() {
 /// lifetimes). Other times you can afford a reference, which is more efficient, in which case
 /// SimpleRefPeerManager is the more appropriate type. Defining these type aliases prevents
 /// issues such as overly long function definitions.
-pub type SimpleArcPeerManager<SD, M, T, F, C, L> = Arc<PeerManager<SD, Arc<SimpleArcChannelManager<M, T, F, L>>, Arc<NetGraphMsgHandler<Arc<C>, Arc<L>>>, Arc<L>>>;
+pub type SimpleArcPeerManager<SD, M, T, F, C, L> = PeerManager<SD, Arc<SimpleArcChannelManager<M, T, F, L>>, Arc<NetGraphMsgHandler<Arc<C>, Arc<L>>>, Arc<L>>;
 
 /// 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
@@ -192,14 +321,25 @@ pub type SimpleArcPeerManager<SD, M, T, F, C, L> = Arc<PeerManager<SD, Arc<Simpl
 /// helps with issues such as long function definitions.
 pub type SimpleRefPeerManager<'a, 'b, 'c, 'd, 'e, 'f, 'g, SD, M, T, F, C, L> = PeerManager<SD, SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, M, T, F, L>, &'e NetGraphMsgHandler<&'g C, &'f L>, &'f L>;
 
-/// A PeerManager manages a set of peers, described by their SocketDescriptor and marshalls socket
-/// events into messages which it passes on to its MessageHandlers.
+/// A PeerManager manages a set of peers, described by their [`SocketDescriptor`] and marshalls
+/// socket events into messages which it passes on to its [`MessageHandler`].
+///
+/// Locks are taken internally, so you must never assume that reentrancy from a
+/// [`SocketDescriptor`] call back into [`PeerManager`] methods will not deadlock.
+///
+/// Calls to [`read_event`] will decode relevant messages and pass them to the
+/// [`ChannelMessageHandler`], likely doing message processing in-line. Thus, the primary form of
+/// parallelism in Rust-Lightning is in calls to [`read_event`]. Note, however, that calls to any
+/// [`PeerManager`] functions related to the same connection must occur only in serial, making new
+/// calls only after previous ones have returned.
 ///
 /// Rather than using a plain PeerManager, it is preferable to use either a SimpleArcPeerManager
 /// a SimpleRefPeerManager, for conciseness. See their documentation for more details, but
 /// essentially you should default to using a SimpleRefPeerManager, and use a
 /// SimpleArcPeerManager when you require a PeerManager with a static lifetime, such as when
 /// you're using lightning-net-tokio.
+///
+/// [`read_event`]: PeerManager::read_event
 pub struct PeerManager<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> where
                CM::Target: ChannelMessageHandler,
                RM::Target: RoutingMessageHandler,
@@ -242,8 +382,44 @@ macro_rules! encode_msg {
        }}
 }
 
-/// Manages and reacts to connection events. You probably want to use file descriptors as PeerIds.
-/// PeerIds may repeat, but only after socket_disconnected() has been called.
+impl<Descriptor: SocketDescriptor, CM: Deref, L: Deref> PeerManager<Descriptor, CM, IgnoringMessageHandler, L> where
+               CM::Target: ChannelMessageHandler,
+               L::Target: Logger {
+       /// Constructs a new PeerManager with the given ChannelMessageHandler. No routing message
+       /// handler is used and network graph messages are ignored.
+       ///
+       /// ephemeral_random_data is used to derive per-connection ephemeral keys and must be
+       /// cryptographically secure random bytes.
+       ///
+       /// (C-not exported) as we can't export a PeerManager with a dummy route handler
+       pub fn new_channel_only(channel_message_handler: CM, our_node_secret: SecretKey, ephemeral_random_data: &[u8; 32], logger: L) -> Self {
+               Self::new(MessageHandler {
+                       chan_handler: channel_message_handler,
+                       route_handler: IgnoringMessageHandler{},
+               }, our_node_secret, ephemeral_random_data, logger)
+       }
+}
+
+impl<Descriptor: SocketDescriptor, RM: Deref, L: Deref> PeerManager<Descriptor, ErroringMessageHandler, RM, L> where
+               RM::Target: RoutingMessageHandler,
+               L::Target: Logger {
+       /// Constructs a new PeerManager with the given RoutingMessageHandler. No channel message
+       /// handler is used and messages related to channels will be ignored (or generate error
+       /// messages). Note that some other lightning implementations time-out connections after some
+       /// time if no channel is built with the peer.
+       ///
+       /// ephemeral_random_data is used to derive per-connection ephemeral keys and must be
+       /// cryptographically secure random bytes.
+       ///
+       /// (C-not exported) as we can't export a PeerManager with a dummy channel handler
+       pub fn new_routing_only(routing_message_handler: RM, our_node_secret: SecretKey, ephemeral_random_data: &[u8; 32], logger: L) -> Self {
+               Self::new(MessageHandler {
+                       chan_handler: ErroringMessageHandler::new(),
+                       route_handler: routing_message_handler,
+               }, our_node_secret, ephemeral_random_data, logger)
+       }
+}
+
 impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<Descriptor, CM, RM, L> where
                CM::Target: ChannelMessageHandler,
                RM::Target: RoutingMessageHandler,
@@ -259,7 +435,6 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                        message_handler,
                        peers: Mutex::new(PeerHolder {
                                peers: HashMap::new(),
-                               peers_needing_send: HashSet::new(),
                                node_id_to_descriptor: HashMap::new()
                        }),
                        our_node_secret,
@@ -304,8 +479,10 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
        ///
        /// Returns a small number of bytes to send to the remote node (currently always 50).
        ///
-       /// Panics if descriptor is duplicative with some other descriptor which has not yet had a
-       /// socket_disconnected().
+       /// Panics if descriptor is duplicative with some other descriptor which has not yet been
+       /// [`socket_disconnected()`].
+       ///
+       /// [`socket_disconnected()`]: PeerManager::socket_disconnected
        pub fn new_outbound_connection(&self, their_node_id: PublicKey, descriptor: Descriptor) -> Result<Vec<u8>, PeerHandleError> {
                let mut peer_encryptor = PeerChannelEncryptor::new_outbound(their_node_id.clone(), self.get_ephemeral_key());
                let res = peer_encryptor.get_act_one().to_vec();
@@ -314,7 +491,6 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                let mut peers = self.peers.lock().unwrap();
                if peers.peers.insert(descriptor, Peer {
                        channel_encryptor: peer_encryptor,
-                       outbound: true,
                        their_node_id: None,
                        their_features: None,
 
@@ -342,8 +518,10 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
        /// call socket_disconnected for the new descriptor but must disconnect the connection
        /// immediately.
        ///
-       /// Panics if descriptor is duplicative with some other descriptor which has not yet had
-       /// socket_disconnected called.
+       /// Panics if descriptor is duplicative with some other descriptor which has not yet been
+       /// [`socket_disconnected()`].
+       ///
+       /// [`socket_disconnected()`]: PeerManager::socket_disconnected
        pub fn new_inbound_connection(&self, descriptor: Descriptor) -> Result<(), PeerHandleError> {
                let peer_encryptor = PeerChannelEncryptor::new_inbound(&self.our_node_secret);
                let pending_read_buffer = [0; 50].to_vec(); // Noise act one is 50 bytes
@@ -351,7 +529,6 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                let mut peers = self.peers.lock().unwrap();
                if peers.peers.insert(descriptor, Peer {
                        channel_encryptor: peer_encryptor,
-                       outbound: false,
                        their_node_id: None,
                        their_features: None,
 
@@ -373,29 +550,20 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
        }
 
        fn do_attempt_write_data(&self, descriptor: &mut Descriptor, peer: &mut Peer) {
-               macro_rules! encode_and_send_msg {
-                       ($msg: expr) => {
-                               {
-                                       log_trace!(self.logger, "Encoding and sending sync update message of type {} to {}", $msg.type_id(), log_pubkey!(peer.their_node_id.unwrap()));
-                                       peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!($msg)[..]));
-                               }
-                       }
-               }
-               const MSG_BUFF_SIZE: usize = 10;
                while !peer.awaiting_write_event {
-                       if peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE {
+                       if peer.pending_outbound_buffer.len() < OUTBOUND_BUFFER_LIMIT_READ_PAUSE {
                                match peer.sync_status {
                                        InitSyncTracker::NoSyncRequested => {},
                                        InitSyncTracker::ChannelsSyncing(c) if c < 0xffff_ffff_ffff_ffff => {
-                                               let steps = ((MSG_BUFF_SIZE - peer.pending_outbound_buffer.len() + 2) / 3) as u8;
+                                               let steps = ((OUTBOUND_BUFFER_LIMIT_READ_PAUSE - peer.pending_outbound_buffer.len() + 2) / 3) as u8;
                                                let all_messages = self.message_handler.route_handler.get_next_channel_announcements(c, steps);
                                                for &(ref announce, ref update_a_option, ref update_b_option) in all_messages.iter() {
-                                                       encode_and_send_msg!(announce);
+                                                       self.enqueue_message(peer, announce);
                                                        if let &Some(ref update_a) = update_a_option {
-                                                               encode_and_send_msg!(update_a);
+                                                               self.enqueue_message(peer, update_a);
                                                        }
                                                        if let &Some(ref update_b) = update_b_option {
-                                                               encode_and_send_msg!(update_b);
+                                                               self.enqueue_message(peer, update_b);
                                                        }
                                                        peer.sync_status = InitSyncTracker::ChannelsSyncing(announce.contents.short_channel_id + 1);
                                                }
@@ -404,10 +572,10 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                                }
                                        },
                                        InitSyncTracker::ChannelsSyncing(c) if c == 0xffff_ffff_ffff_ffff => {
-                                               let steps = (MSG_BUFF_SIZE - peer.pending_outbound_buffer.len()) as u8;
+                                               let steps = (OUTBOUND_BUFFER_LIMIT_READ_PAUSE - peer.pending_outbound_buffer.len()) as u8;
                                                let all_messages = self.message_handler.route_handler.get_next_node_announcements(None, steps);
                                                for msg in all_messages.iter() {
-                                                       encode_and_send_msg!(msg);
+                                                       self.enqueue_message(peer, msg);
                                                        peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
                                                }
                                                if all_messages.is_empty() || all_messages.len() != steps as usize {
@@ -416,10 +584,10 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                        },
                                        InitSyncTracker::ChannelsSyncing(_) => unreachable!(),
                                        InitSyncTracker::NodesSyncing(key) => {
-                                               let steps = (MSG_BUFF_SIZE - peer.pending_outbound_buffer.len()) as u8;
+                                               let steps = (OUTBOUND_BUFFER_LIMIT_READ_PAUSE - peer.pending_outbound_buffer.len()) as u8;
                                                let all_messages = self.message_handler.route_handler.get_next_node_announcements(Some(&key), steps);
                                                for msg in all_messages.iter() {
-                                                       encode_and_send_msg!(msg);
+                                                       self.enqueue_message(peer, msg);
                                                        peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id);
                                                }
                                                if all_messages.is_empty() || all_messages.len() != steps as usize {
@@ -435,7 +603,7 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                        Some(buff) => buff,
                                };
 
-                               let should_be_reading = peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE;
+                               let should_be_reading = peer.pending_outbound_buffer.len() < OUTBOUND_BUFFER_LIMIT_READ_PAUSE;
                                let pending = &next_buff[peer.pending_outbound_buffer_first_msg_offset..];
                                let data_sent = descriptor.send_data(pending, should_be_reading);
                                peer.pending_outbound_buffer_first_msg_offset += data_sent;
@@ -453,16 +621,23 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
        ///
        /// May return an Err to indicate that the connection should be closed.
        ///
-       /// Will most likely call send_data on the descriptor passed in (or the descriptor handed into
-       /// new_*\_connection) before returning. Thus, be very careful with reentrancy issues! The
-       /// invariants around calling write_buffer_space_avail in case a write did not fully complete
-       /// must still hold - be ready to call write_buffer_space_avail again if a write call generated
-       /// here isn't sufficient! Panics if the descriptor was not previously registered in a
-       /// new_\*_connection event.
+       /// May call [`send_data`] on the descriptor passed in (or an equal descriptor) before
+       /// returning. Thus, be very careful with reentrancy issues! The invariants around calling
+       /// [`write_buffer_space_avail`] in case a write did not fully complete must still hold - be
+       /// ready to call `[write_buffer_space_avail`] again if a write call generated here isn't
+       /// sufficient!
+       ///
+       /// [`send_data`]: SocketDescriptor::send_data
+       /// [`write_buffer_space_avail`]: PeerManager::write_buffer_space_avail
        pub fn write_buffer_space_avail(&self, descriptor: &mut Descriptor) -> Result<(), PeerHandleError> {
                let mut peers = self.peers.lock().unwrap();
                match peers.peers.get_mut(descriptor) {
-                       None => panic!("Descriptor for write_event is not already known to PeerManager"),
+                       None => {
+                               // This is most likely a simple race condition where the user found that the socket
+                               // was writeable, then we told the user to `disconnect_socket()`, then they called
+                               // this method. Return an error to make sure we get disconnected.
+                               return Err(PeerHandleError { no_connection_possible: false });
+                       },
                        Some(peer) => {
                                peer.awaiting_write_event = false;
                                self.do_attempt_write_data(descriptor, peer);
@@ -475,14 +650,16 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
        ///
        /// May return an Err to indicate that the connection should be closed.
        ///
-       /// Will *not* call back into send_data on any descriptors to avoid reentrancy complexity.
-       /// Thus, however, you almost certainly want to call process_events() after any read_event to
-       /// generate send_data calls to handle responses.
+       /// Will *not* call back into [`send_data`] on any descriptors to avoid reentrancy complexity.
+       /// Thus, however, you should call [`process_events`] after any `read_event` to generate
+       /// [`send_data`] calls to handle responses.
        ///
-       /// If Ok(true) is returned, further read_events should not be triggered until a send_data call
-       /// on this file descriptor has resume_read set (preventing DoS issues in the send buffer).
+       /// If `Ok(true)` is returned, further read_events should not be triggered until a
+       /// [`send_data`] call on this descriptor has `resume_read` set (preventing DoS issues in the
+       /// send buffer).
        ///
-       /// Panics if the descriptor was not previously registered in a new_*_connection event.
+       /// [`send_data`]: SocketDescriptor::send_data
+       /// [`process_events`]: PeerManager::process_events
        pub fn read_event(&self, peer_descriptor: &mut Descriptor, data: &[u8]) -> Result<bool, PeerHandleError> {
                match self.do_read_event(peer_descriptor, data) {
                        Ok(res) => Ok(res),
@@ -494,22 +671,28 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
        }
 
        /// Append a message to a peer's pending outbound/write buffer, and update the map of peers needing sends accordingly.
-       fn enqueue_message<M: Encode + Writeable>(&self, peers_needing_send: &mut HashSet<Descriptor>, peer: &mut Peer, descriptor: Descriptor, message: &M) {
+       fn enqueue_message<M: Encode + Writeable + Debug>(&self, peer: &mut Peer, message: &M) {
                let mut buffer = VecWriter(Vec::new());
                wire::write(message, &mut buffer).unwrap(); // crash if the write failed
                let encoded_message = buffer.0;
 
-               log_trace!(self.logger, "Enqueueing message of type {} to {}", message.type_id(), log_pubkey!(peer.their_node_id.unwrap()));
+               log_trace!(self.logger, "Enqueueing message {:?} to {}", message, log_pubkey!(peer.their_node_id.unwrap()));
                peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_message[..]));
-               peers_needing_send.insert(descriptor);
        }
 
        fn do_read_event(&self, peer_descriptor: &mut Descriptor, data: &[u8]) -> Result<bool, PeerHandleError> {
                let pause_read = {
                        let mut peers_lock = self.peers.lock().unwrap();
                        let peers = &mut *peers_lock;
+                       let mut msgs_to_forward = Vec::new();
+                       let mut peer_node_id = None;
                        let pause_read = match peers.peers.get_mut(peer_descriptor) {
-                               None => panic!("Descriptor for read_event is not already known to PeerManager"),
+                               None => {
+                                       // This is most likely a simple race condition where the user read some bytes
+                                       // from the socket, then we told the user to `disconnect_socket()`, then they
+                                       // called this method. Return an error to make sure we get disconnected.
+                                       return Err(PeerHandleError { no_connection_possible: false });
+                               },
                                Some(peer) => {
                                        assert!(peer.pending_read_buffer.len() > 0);
                                        assert!(peer.pending_read_buffer.len() > peer.pending_read_buffer_pos);
@@ -534,16 +717,20 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                                                                        match e.action {
                                                                                                msgs::ErrorAction::DisconnectPeer { msg: _ } => {
                                                                                                        //TODO: Try to push msg
-                                                                                                       log_trace!(self.logger, "Got Err handling message, disconnecting peer because {}", e.err);
+                                                                                                       log_debug!(self.logger, "Error handling message; disconnecting peer with: {}", e.err);
                                                                                                        return Err(PeerHandleError{ no_connection_possible: false });
                                                                                                },
+                                                                                               msgs::ErrorAction::IgnoreAndLog(level) => {
+                                                                                                       log_given_level!(self.logger, level, "Error handling message; ignoring: {}", e.err);
+                                                                                                       continue
+                                                                                               },
                                                                                                msgs::ErrorAction::IgnoreError => {
-                                                                                                       log_trace!(self.logger, "Got Err handling message, ignoring because {}", e.err);
+                                                                                                       log_debug!(self.logger, "Error handling message; ignoring: {}", e.err);
                                                                                                        continue;
                                                                                                },
                                                                                                msgs::ErrorAction::SendErrorMessage { msg } => {
-                                                                                                       log_trace!(self.logger, "Got Err handling message, sending Error message because {}", e.err);
-                                                                                                       self.enqueue_message(&mut peers.peers_needing_send, peer, peer_descriptor.clone(), &msg);
+                                                                                                       log_debug!(self.logger, "Error handling message; sending error message with: {}", e.err);
+                                                                                                       self.enqueue_message(peer, &msg);
                                                                                                        continue;
                                                                                                },
                                                                                        }
@@ -561,7 +748,7 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                                                                        return Err(PeerHandleError{ no_connection_possible: false })
                                                                                },
                                                                                hash_map::Entry::Vacant(entry) => {
-                                                                                       log_trace!(self.logger, "Finished noise handshake for connection with {}", log_pubkey!(peer.their_node_id.unwrap()));
+                                                                                       log_debug!(self.logger, "Finished noise handshake for connection with {}", log_pubkey!(peer.their_node_id.unwrap()));
                                                                                        entry.insert(peer_descriptor.clone())
                                                                                },
                                                                        };
@@ -585,7 +772,7 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                                                        insert_node_id!();
                                                                        let features = InitFeatures::known();
                                                                        let resp = msgs::Init { features };
-                                                                       self.enqueue_message(&mut peers.peers_needing_send, peer, peer_descriptor.clone(), &resp);
+                                                                       self.enqueue_message(peer, &resp);
                                                                },
                                                                NextNoiseStep::ActThree => {
                                                                        let their_node_id = try_potential_handleerror!(peer.channel_encryptor.process_act_three(&peer.pending_read_buffer[..]));
@@ -593,6 +780,9 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                                                        peer.pending_read_is_header = true;
                                                                        peer.their_node_id = Some(their_node_id);
                                                                        insert_node_id!();
+                                                                       let features = InitFeatures::known();
+                                                                       let resp = msgs::Init { features };
+                                                                       self.enqueue_message(peer, &resp);
                                                                },
                                                                NextNoiseStep::NoiseComplete => {
                                                                        if peer.pending_read_is_header {
@@ -619,7 +809,7 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                                                                                match e {
                                                                                                        msgs::DecodeError::UnknownVersion => return Err(PeerHandleError { no_connection_possible: false }),
                                                                                                        msgs::DecodeError::UnknownRequiredFeature => {
-                                                                                                               log_debug!(self.logger, "Got a channel/node announcement with an known required feature flag, you may want to update!");
+                                                                                                               log_trace!(self.logger, "Got a channel/node announcement with an known required feature flag, you may want to update!");
                                                                                                                continue;
                                                                                                        }
                                                                                                        msgs::DecodeError::InvalidValue => {
@@ -632,17 +822,26 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                                                                                        }
                                                                                                        msgs::DecodeError::BadLengthDescriptor => return Err(PeerHandleError { no_connection_possible: false }),
                                                                                                        msgs::DecodeError::Io(_) => return Err(PeerHandleError { no_connection_possible: false }),
+                                                                                                       msgs::DecodeError::UnsupportedCompression => {
+                                                                                                               log_trace!(self.logger, "We don't support zlib-compressed message fields, ignoring message");
+                                                                                                               continue;
+                                                                                                       }
                                                                                                }
                                                                                        }
                                                                                };
 
-                                                                               if let Err(handling_error) = self.handle_message(&mut peers.peers_needing_send, peer, peer_descriptor.clone(), message){
-                                                                                       match handling_error {
+                                                                               match self.handle_message(peer, message) {
+                                                                                       Err(handling_error) => match handling_error {
                                                                                                MessageHandlingError::PeerHandleError(e) => { return Err(e) },
                                                                                                MessageHandlingError::LightningError(e) => {
                                                                                                        try_potential_handleerror!(Err(e));
                                                                                                },
-                                                                                       }
+                                                                                       },
+                                                                                       Ok(Some(msg)) => {
+                                                                                               peer_node_id = Some(peer.their_node_id.expect("After noise is complete, their_node_id is always set"));
+                                                                                               msgs_to_forward.push(msg);
+                                                                                       },
+                                                                                       Ok(None) => {},
                                                                                }
                                                                        }
                                                                }
@@ -650,12 +849,14 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                                }
                                        }
 
-                                       self.do_attempt_write_data(peer_descriptor, peer);
-
-                                       peer.pending_outbound_buffer.len() > 10 // pause_read
+                                       peer.pending_outbound_buffer.len() > OUTBOUND_BUFFER_LIMIT_READ_PAUSE // pause_read
                                }
                        };
 
+                       for msg in msgs_to_forward.drain(..) {
+                               self.forward_broadcast_msg(peers, &msg, peer_node_id.as_ref());
+                       }
+
                        pause_read
                };
 
@@ -663,21 +864,24 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
        }
 
        /// Process an incoming message and return a decision (ok, lightning error, peer handling error) regarding the next action with the peer
-       fn handle_message(&self, peers_needing_send: &mut HashSet<Descriptor>, peer: &mut Peer, peer_descriptor: Descriptor, message: wire::Message) -> Result<(), MessageHandlingError> {
-               log_trace!(self.logger, "Received message of type {} from {}", message.type_id(), log_pubkey!(peer.their_node_id.unwrap()));
+       /// Returns the message back if it needs to be broadcasted to all other peers.
+       fn handle_message(&self, peer: &mut Peer, message: wire::Message) -> Result<Option<wire::Message>, MessageHandlingError> {
+               log_trace!(self.logger, "Received message {:?} from {}", message, log_pubkey!(peer.their_node_id.unwrap()));
 
                // Need an Init as first message
                if let wire::Message::Init(_) = message {
                } else if peer.their_features.is_none() {
-                       log_trace!(self.logger, "Peer {} sent non-Init first message", log_pubkey!(peer.their_node_id.unwrap()));
+                       log_debug!(self.logger, "Peer {} sent non-Init first message", log_pubkey!(peer.their_node_id.unwrap()));
                        return Err(PeerHandleError{ no_connection_possible: false }.into());
                }
 
+               let mut should_forward = None;
+
                match message {
                        // Setup and Control messages:
                        wire::Message::Init(msg) => {
                                if msg.features.requires_unknown_bits() {
-                                       log_info!(self.logger, "Peer features required unknown version bits");
+                                       log_debug!(self.logger, "Peer features required unknown version bits");
                                        return Err(PeerHandleError{ no_connection_possible: true }.into());
                                }
                                if peer.their_features.is_some() {
@@ -696,19 +900,12 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
 
                                if msg.features.initial_routing_sync() {
                                        peer.sync_status = InitSyncTracker::ChannelsSyncing(0);
-                                       peers_needing_send.insert(peer_descriptor.clone());
                                }
                                if !msg.features.supports_static_remote_key() {
                                        log_debug!(self.logger, "Peer {} does not support static remote key, disconnecting with no_connection_possible", log_pubkey!(peer.their_node_id.unwrap()));
                                        return Err(PeerHandleError{ no_connection_possible: true }.into());
                                }
 
-                               if !peer.outbound {
-                                       let features = InitFeatures::known();
-                                       let resp = msgs::Init { features };
-                                       self.enqueue_message(peers_needing_send, peer, peer_descriptor.clone(), &resp);
-                               }
-
                                self.message_handler.route_handler.sync_routing_table(&peer.their_node_id.unwrap(), &msg);
 
                                self.message_handler.chan_handler.peer_connected(&peer.their_node_id.unwrap(), &msg);
@@ -737,7 +934,7 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                        wire::Message::Ping(msg) => {
                                if msg.ponglen < 65532 {
                                        let resp = msgs::Pong { byteslen: msg.ponglen };
-                                       self.enqueue_message(peers_needing_send, peer, peer_descriptor.clone(), &resp);
+                                       self.enqueue_message(peer, &resp);
                                }
                        },
                        wire::Message::Pong(_msg) => {
@@ -801,33 +998,22 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                self.message_handler.chan_handler.handle_announcement_signatures(&peer.their_node_id.unwrap(), &msg);
                        },
                        wire::Message::ChannelAnnouncement(msg) => {
-                               let should_forward = match self.message_handler.route_handler.handle_channel_announcement(&msg) {
-                                       Ok(v) => v,
-                                       Err(e) => { return Err(e.into()); },
-                               };
-
-                               if should_forward {
-                                       // TODO: forward msg along to all our other peers!
+                               if self.message_handler.route_handler.handle_channel_announcement(&msg)
+                                               .map_err(|e| -> MessageHandlingError { e.into() })? {
+                                       should_forward = Some(wire::Message::ChannelAnnouncement(msg));
                                }
                        },
                        wire::Message::NodeAnnouncement(msg) => {
-                               let should_forward = match self.message_handler.route_handler.handle_node_announcement(&msg) {
-                                       Ok(v) => v,
-                                       Err(e) => { return Err(e.into()); },
-                               };
-
-                               if should_forward {
-                                       // TODO: forward msg along to all our other peers!
+                               if self.message_handler.route_handler.handle_node_announcement(&msg)
+                                               .map_err(|e| -> MessageHandlingError { e.into() })? {
+                                       should_forward = Some(wire::Message::NodeAnnouncement(msg));
                                }
                        },
                        wire::Message::ChannelUpdate(msg) => {
-                               let should_forward = match self.message_handler.route_handler.handle_channel_update(&msg) {
-                                       Ok(v) => v,
-                                       Err(e) => { return Err(e.into()); },
-                               };
-
-                               if should_forward {
-                                       // TODO: forward msg along to all our other peers!
+                               self.message_handler.chan_handler.handle_channel_update(&peer.their_node_id.unwrap(), &msg);
+                               if self.message_handler.route_handler.handle_channel_update(&msg)
+                                               .map_err(|e| -> MessageHandlingError { e.into() })? {
+                                       should_forward = Some(wire::Message::ChannelUpdate(msg));
                                }
                        },
                        wire::Message::QueryShortChannelIds(msg) => {
@@ -856,234 +1042,234 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                log_trace!(self.logger, "Received unknown odd message of type {}, ignoring", msg_type);
                        }
                };
-               Ok(())
+               Ok(should_forward)
+       }
+
+       fn forward_broadcast_msg(&self, peers: &mut PeerHolder<Descriptor>, msg: &wire::Message, except_node: Option<&PublicKey>) {
+               match msg {
+                       wire::Message::ChannelAnnouncement(ref msg) => {
+                               log_trace!(self.logger, "Sending message to all peers except {:?} or the announced channel's counterparties: {:?}", except_node, msg);
+                               let encoded_msg = encode_msg!(msg);
+
+                               for (_, peer) in peers.peers.iter_mut() {
+                                       if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
+                                                       !peer.should_forward_channel_announcement(msg.contents.short_channel_id) {
+                                               continue
+                                       }
+                                       if peer.pending_outbound_buffer.len() > OUTBOUND_BUFFER_LIMIT_DROP_GOSSIP {
+                                               log_trace!(self.logger, "Skipping broadcast message to {:?} as its outbound buffer is full", peer.their_node_id);
+                                               continue;
+                                       }
+                                       if peer.their_node_id.as_ref() == Some(&msg.contents.node_id_1) ||
+                                          peer.their_node_id.as_ref() == Some(&msg.contents.node_id_2) {
+                                               continue;
+                                       }
+                                       if except_node.is_some() && peer.their_node_id.as_ref() == except_node {
+                                               continue;
+                                       }
+                                       peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
+                               }
+                       },
+                       wire::Message::NodeAnnouncement(ref msg) => {
+                               log_trace!(self.logger, "Sending message to all peers except {:?} or the announced node: {:?}", except_node, msg);
+                               let encoded_msg = encode_msg!(msg);
+
+                               for (_, peer) in peers.peers.iter_mut() {
+                                       if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
+                                                       !peer.should_forward_node_announcement(msg.contents.node_id) {
+                                               continue
+                                       }
+                                       if peer.pending_outbound_buffer.len() > OUTBOUND_BUFFER_LIMIT_DROP_GOSSIP {
+                                               log_trace!(self.logger, "Skipping broadcast message to {:?} as its outbound buffer is full", peer.their_node_id);
+                                               continue;
+                                       }
+                                       if peer.their_node_id.as_ref() == Some(&msg.contents.node_id) {
+                                               continue;
+                                       }
+                                       if except_node.is_some() && peer.their_node_id.as_ref() == except_node {
+                                               continue;
+                                       }
+                                       peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
+                               }
+                       },
+                       wire::Message::ChannelUpdate(ref msg) => {
+                               log_trace!(self.logger, "Sending message to all peers except {:?}: {:?}", except_node, msg);
+                               let encoded_msg = encode_msg!(msg);
+
+                               for (_, peer) in peers.peers.iter_mut() {
+                                       if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
+                                                       !peer.should_forward_channel_announcement(msg.contents.short_channel_id)  {
+                                               continue
+                                       }
+                                       if peer.pending_outbound_buffer.len() > OUTBOUND_BUFFER_LIMIT_DROP_GOSSIP {
+                                               log_trace!(self.logger, "Skipping broadcast message to {:?} as its outbound buffer is full", peer.their_node_id);
+                                               continue;
+                                       }
+                                       if except_node.is_some() && peer.their_node_id.as_ref() == except_node {
+                                               continue;
+                                       }
+                                       peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
+                               }
+                       },
+                       _ => debug_assert!(false, "We shouldn't attempt to forward anything but gossip messages"),
+               }
        }
 
        /// Checks for any events generated by our handlers and processes them. Includes sending most
        /// response messages as well as messages generated by calls to handler functions directly (eg
-       /// functions like ChannelManager::process_pending_htlc_forward or send_payment).
+       /// functions like [`ChannelManager::process_pending_htlc_forwards`] or [`send_payment`]).
+       ///
+       /// May call [`send_data`] on [`SocketDescriptor`]s. Thus, be very careful with reentrancy
+       /// issues!
+       ///
+       /// [`send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
+       /// [`ChannelManager::process_pending_htlc_forwards`]: crate::ln::channelmanager::ChannelManager::process_pending_htlc_forwards
+       /// [`send_data`]: SocketDescriptor::send_data
        pub fn process_events(&self) {
                {
                        // 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_lock = self.peers.lock().unwrap();
                        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 mut peers_lock = self.peers.lock().unwrap();
                        let peers = &mut *peers_lock;
                        for event in events_generated.drain(..) {
                                macro_rules! get_peer_for_forwarding {
-                                       ($node_id: expr, $handle_no_such_peer: block) => {
+                                       ($node_id: expr) => {
                                                {
-                                                       let descriptor = match peers.node_id_to_descriptor.get($node_id) {
-                                                               Some(descriptor) => descriptor.clone(),
+                                                       match peers.node_id_to_descriptor.get($node_id) {
+                                                               Some(descriptor) => match peers.peers.get_mut(&descriptor) {
+                                                                       Some(peer) => {
+                                                                               if peer.their_features.is_none() {
+                                                                                       continue;
+                                                                               }
+                                                                               peer
+                                                                       },
+                                                                       None => panic!("Inconsistent peers set state!"),
+                                                               },
                                                                None => {
-                                                                       $handle_no_such_peer;
                                                                        continue;
                                                                },
-                                                       };
-                                                       match peers.peers.get_mut(&descriptor) {
-                                                               Some(peer) => {
-                                                                       if peer.their_features.is_none() {
-                                                                               $handle_no_such_peer;
-                                                                               continue;
-                                                                       }
-                                                                       (descriptor, peer)
-                                                               },
-                                                               None => panic!("Inconsistent peers set state!"),
                                                        }
                                                }
                                        }
                                }
                                match event {
                                        MessageSendEvent::SendAcceptChannel { ref node_id, ref msg } => {
-                                               log_trace!(self.logger, "Handling SendAcceptChannel event in peer_handler for node {} for channel {}",
+                                               log_debug!(self.logger, "Handling SendAcceptChannel event in peer_handler for node {} for channel {}",
                                                                log_pubkey!(node_id),
                                                                log_bytes!(msg.temporary_channel_id));
-                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
-                                                               //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
-                                                       });
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
                                        },
                                        MessageSendEvent::SendOpenChannel { ref node_id, ref msg } => {
-                                               log_trace!(self.logger, "Handling SendOpenChannel event in peer_handler for node {} for channel {}",
+                                               log_debug!(self.logger, "Handling SendOpenChannel event in peer_handler for node {} for channel {}",
                                                                log_pubkey!(node_id),
                                                                log_bytes!(msg.temporary_channel_id));
-                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
-                                                               //TODO: Drop the pending channel? (or just let it timeout, but that sucks)
-                                                       });
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
                                        },
                                        MessageSendEvent::SendFundingCreated { ref node_id, ref msg } => {
-                                               log_trace!(self.logger, "Handling SendFundingCreated event in peer_handler for node {} for channel {} (which becomes {})",
+                                               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));
-                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
-                                                               //TODO: generate a DiscardFunding event indicating to the wallet that
-                                                               //they should just throw away this funding transaction
-                                                       });
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               // 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(get_peer_for_forwarding!(node_id), msg);
                                        },
                                        MessageSendEvent::SendFundingSigned { ref node_id, ref msg } => {
-                                               log_trace!(self.logger, "Handling SendFundingSigned event in peer_handler for node {} for channel {}",
+                                               log_debug!(self.logger, "Handling SendFundingSigned event in peer_handler for node {} for channel {}",
                                                                log_pubkey!(node_id),
                                                                log_bytes!(msg.channel_id));
-                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
-                                                               //TODO: generate a DiscardFunding event indicating to the wallet that
-                                                               //they should just throw away this funding transaction
-                                                       });
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
                                        },
                                        MessageSendEvent::SendFundingLocked { ref node_id, ref msg } => {
-                                               log_trace!(self.logger, "Handling SendFundingLocked event in peer_handler for node {} for channel {}",
+                                               log_debug!(self.logger, "Handling SendFundingLocked event in peer_handler for node {} for channel {}",
                                                                log_pubkey!(node_id),
                                                                log_bytes!(msg.channel_id));
-                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
-                                                               //TODO: Do whatever we're gonna do for handling dropped messages
-                                                       });
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
                                        },
                                        MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => {
-                                               log_trace!(self.logger, "Handling SendAnnouncementSignatures event in peer_handler for node {} for channel {})",
+                                               log_debug!(self.logger, "Handling SendAnnouncementSignatures event in peer_handler for node {} for channel {})",
                                                                log_pubkey!(node_id),
                                                                log_bytes!(msg.channel_id));
-                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
-                                                               //TODO: generate a DiscardFunding event indicating to the wallet that
-                                                               //they should just throw away this funding transaction
-                                                       });
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               self.enqueue_message(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_trace!(self.logger, "Handling UpdateHTLCs event in peer_handler for node {} with {} adds, {} fulfills, {} fails for channel {}",
+                                               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 descriptor, peer) = get_peer_for_forwarding!(node_id, {
-                                                               //TODO: Do whatever we're gonna do for handling dropped messages
-                                                       });
+                                               let peer = get_peer_for_forwarding!(node_id);
                                                for msg in update_add_htlcs {
-                                                       peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
+                                                       self.enqueue_message(peer, msg);
                                                }
                                                for msg in update_fulfill_htlcs {
-                                                       peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
+                                                       self.enqueue_message(peer, msg);
                                                }
                                                for msg in update_fail_htlcs {
-                                                       peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
+                                                       self.enqueue_message(peer, msg);
                                                }
                                                for msg in update_fail_malformed_htlcs {
-                                                       peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
+                                                       self.enqueue_message(peer, msg);
                                                }
                                                if let &Some(ref msg) = update_fee {
-                                                       peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
+                                                       self.enqueue_message(peer, msg);
                                                }
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(commitment_signed)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               self.enqueue_message(peer, commitment_signed);
                                        },
                                        MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => {
-                                               log_trace!(self.logger, "Handling SendRevokeAndACK event in peer_handler for node {} for channel {}",
+                                               log_debug!(self.logger, "Handling SendRevokeAndACK event in peer_handler for node {} for channel {}",
                                                                log_pubkey!(node_id),
                                                                log_bytes!(msg.channel_id));
-                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
-                                                               //TODO: Do whatever we're gonna do for handling dropped messages
-                                                       });
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
                                        },
                                        MessageSendEvent::SendClosingSigned { ref node_id, ref msg } => {
-                                               log_trace!(self.logger, "Handling SendClosingSigned event in peer_handler for node {} for channel {}",
+                                               log_debug!(self.logger, "Handling SendClosingSigned event in peer_handler for node {} for channel {}",
                                                                log_pubkey!(node_id),
                                                                log_bytes!(msg.channel_id));
-                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
-                                                               //TODO: Do whatever we're gonna do for handling dropped messages
-                                                       });
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
                                        },
                                        MessageSendEvent::SendShutdown { ref node_id, ref msg } => {
-                                               log_trace!(self.logger, "Handling Shutdown event in peer_handler for node {} for channel {}",
+                                               log_debug!(self.logger, "Handling Shutdown event in peer_handler for node {} for channel {}",
                                                                log_pubkey!(node_id),
                                                                log_bytes!(msg.channel_id));
-                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
-                                                               //TODO: Do whatever we're gonna do for handling dropped messages
-                                                       });
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
                                        },
                                        MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => {
-                                               log_trace!(self.logger, "Handling SendChannelReestablish event in peer_handler for node {} for channel {}",
+                                               log_debug!(self.logger, "Handling SendChannelReestablish event in peer_handler for node {} for channel {}",
                                                                log_pubkey!(node_id),
                                                                log_bytes!(msg.channel_id));
-                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
-                                                               //TODO: Do whatever we're gonna do for handling dropped messages
-                                                       });
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
                                        },
-                                       MessageSendEvent::BroadcastChannelAnnouncement { ref msg, ref update_msg } => {
-                                               log_trace!(self.logger, "Handling BroadcastChannelAnnouncement event in peer_handler for short channel id {}", msg.contents.short_channel_id);
-                                               if self.message_handler.route_handler.handle_channel_announcement(msg).is_ok() && self.message_handler.route_handler.handle_channel_update(update_msg).is_ok() {
-                                                       let encoded_msg = encode_msg!(msg);
-                                                       let encoded_update_msg = encode_msg!(update_msg);
-
-                                                       for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
-                                                               if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
-                                                                               !peer.should_forward_channel_announcement(msg.contents.short_channel_id) {
-                                                                       continue
-                                                               }
-                                                               match peer.their_node_id {
-                                                                       None => continue,
-                                                                       Some(their_node_id) => {
-                                                                               if their_node_id == msg.contents.node_id_1 || their_node_id == msg.contents.node_id_2 {
-                                                                                       continue
-                                                                               }
-                                                                       }
-                                                               }
-                                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
-                                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_update_msg[..]));
-                                                               self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
-                                                       }
+                                       MessageSendEvent::BroadcastChannelAnnouncement { msg, update_msg } => {
+                                               log_debug!(self.logger, "Handling BroadcastChannelAnnouncement event in peer_handler for short channel id {}", msg.contents.short_channel_id);
+                                               if self.message_handler.route_handler.handle_channel_announcement(&msg).is_ok() && self.message_handler.route_handler.handle_channel_update(&update_msg).is_ok() {
+                                                       self.forward_broadcast_msg(peers, &wire::Message::ChannelAnnouncement(msg), None);
+                                                       self.forward_broadcast_msg(peers, &wire::Message::ChannelUpdate(update_msg), None);
                                                }
                                        },
-                                       MessageSendEvent::BroadcastNodeAnnouncement { ref msg } => {
-                                               log_trace!(self.logger, "Handling BroadcastNodeAnnouncement event in peer_handler");
-                                               if self.message_handler.route_handler.handle_node_announcement(msg).is_ok() {
-                                                       let encoded_msg = encode_msg!(msg);
-
-                                                       for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
-                                                               if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
-                                                                               !peer.should_forward_node_announcement(msg.contents.node_id) {
-                                                                       continue
-                                                               }
-                                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
-                                                               self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
-                                                       }
+                                       MessageSendEvent::BroadcastNodeAnnouncement { msg } => {
+                                               log_debug!(self.logger, "Handling BroadcastNodeAnnouncement event in peer_handler");
+                                               if self.message_handler.route_handler.handle_node_announcement(&msg).is_ok() {
+                                                       self.forward_broadcast_msg(peers, &wire::Message::NodeAnnouncement(msg), None);
                                                }
                                        },
-                                       MessageSendEvent::BroadcastChannelUpdate { ref msg } => {
-                                               log_trace!(self.logger, "Handling BroadcastChannelUpdate event in peer_handler for short channel id {}", msg.contents.short_channel_id);
-                                               if self.message_handler.route_handler.handle_channel_update(msg).is_ok() {
-                                                       let encoded_msg = encode_msg!(msg);
-
-                                                       for (ref descriptor, ref mut peer) in peers.peers.iter_mut() {
-                                                               if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_features.is_none() ||
-                                                                               !peer.should_forward_channel_announcement(msg.contents.short_channel_id)  {
-                                                                       continue
-                                                               }
-                                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encoded_msg[..]));
-                                                               self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
-                                                       }
+                                       MessageSendEvent::BroadcastChannelUpdate { msg } => {
+                                               log_debug!(self.logger, "Handling BroadcastChannelUpdate event in peer_handler for short channel id {}", msg.contents.short_channel_id);
+                                               if self.message_handler.route_handler.handle_channel_update(&msg).is_ok() {
+                                                       self.forward_broadcast_msg(peers, &wire::Message::ChannelUpdate(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);
+                                               let peer = get_peer_for_forwarding!(node_id);
+                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
+                                       },
                                        MessageSendEvent::PaymentFailureNetworkUpdate { ref update } => {
                                                self.message_handler.route_handler.handle_htlc_fail_channel_update(update);
                                        },
@@ -1091,13 +1277,12 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                                match *action {
                                                        msgs::ErrorAction::DisconnectPeer { ref msg } => {
                                                                if let Some(mut descriptor) = peers.node_id_to_descriptor.remove(node_id) {
-                                                                       peers.peers_needing_send.remove(&descriptor);
                                                                        if let Some(mut peer) = peers.peers.remove(&descriptor) {
                                                                                if let Some(ref msg) = *msg {
                                                                                        log_trace!(self.logger, "Handling DisconnectPeer HandleError event in peer_handler for node {} with message {}",
                                                                                                        log_pubkey!(node_id),
                                                                                                        msg.data);
-                                                                                       peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_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);
@@ -1109,59 +1294,58 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                                                        self.message_handler.chan_handler.peer_disconnected(&node_id, false);
                                                                }
                                                        },
-                                                       msgs::ErrorAction::IgnoreError => {},
+                                                       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::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);
-                                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {
-                                                                       //TODO: Do whatever we're gonna do for handling dropped messages
-                                                               });
-                                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                                               self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
                                                        },
                                                }
                                        },
                                        MessageSendEvent::SendChannelRangeQuery { ref node_id, ref msg } => {
-                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {});
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
                                        },
                                        MessageSendEvent::SendShortIdsQuery { ref node_id, ref msg } => {
-                                               let (mut descriptor, peer) = get_peer_for_forwarding!(node_id, {});
-                                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg)));
-                                               self.do_attempt_write_data(&mut descriptor, peer);
+                                               self.enqueue_message(get_peer_for_forwarding!(node_id), msg);
+                                       }
+                                       MessageSendEvent::SendReplyChannelRange { ref node_id, ref msg } => {
+                                               log_trace!(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(get_peer_for_forwarding!(node_id), msg);
                                        }
                                }
                        }
 
-                       for mut descriptor in peers.peers_needing_send.drain() {
-                               match peers.peers.get_mut(&descriptor) {
-                                       Some(peer) => self.do_attempt_write_data(&mut descriptor, peer),
-                                       None => panic!("Inconsistent peers set state!"),
-                               }
+                       for (descriptor, peer) in peers.peers.iter_mut() {
+                               self.do_attempt_write_data(&mut (*descriptor).clone(), peer);
                        }
                }
        }
 
        /// Indicates that the given socket descriptor's connection is now closed.
-       ///
-       /// This must only be called if the socket has been disconnected by the peer or your own
-       /// decision to disconnect it and must NOT be called in any case where other parts of this
-       /// library (eg PeerHandleError, explicit disconnect_socket calls) instruct you to disconnect
-       /// the peer.
-       ///
-       /// Panics if the descriptor was not previously registered in a successful new_*_connection event.
        pub fn socket_disconnected(&self, descriptor: &Descriptor) {
                self.disconnect_event_internal(descriptor, false);
        }
 
        fn disconnect_event_internal(&self, descriptor: &Descriptor, no_connection_possible: bool) {
                let mut peers = self.peers.lock().unwrap();
-               peers.peers_needing_send.remove(descriptor);
                let peer_option = peers.peers.remove(descriptor);
                match peer_option {
-                       None => panic!("Descriptor for disconnect_event is not already known to PeerManager"),
+                       None => {
+                               // This is most likely a simple race condition where the user found that the socket
+                               // was disconnected, then we told the user to `disconnect_socket()`, then they
+                               // called this method. Either way we're disconnected, return.
+                       },
                        Some(peer) => {
                                match peer.their_node_id {
                                        Some(node_id) => {
@@ -1176,38 +1360,41 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
 
        /// Disconnect a peer given its node id.
        ///
-       /// Set no_connection_possible to true to prevent any further connection with this peer,
+       /// Set `no_connection_possible` to true to prevent any further connection with this peer,
        /// force-closing any channels we have with it.
        ///
-       /// If a peer is connected, this will call `disconnect_socket` on the descriptor for the peer,
-       /// so be careful about reentrancy issues.
+       /// If a peer is connected, this will call [`disconnect_socket`] on the descriptor for the
+       /// peer. Thus, be very careful about reentrancy issues.
+       ///
+       /// [`disconnect_socket`]: SocketDescriptor::disconnect_socket
        pub fn disconnect_by_node_id(&self, node_id: PublicKey, no_connection_possible: bool) {
                let mut peers_lock = self.peers.lock().unwrap();
                if let Some(mut descriptor) = peers_lock.node_id_to_descriptor.remove(&node_id) {
                        log_trace!(self.logger, "Disconnecting peer with id {} due to client request", node_id);
                        peers_lock.peers.remove(&descriptor);
-                       peers_lock.peers_needing_send.remove(&descriptor);
                        self.message_handler.chan_handler.peer_disconnected(&node_id, no_connection_possible);
                        descriptor.disconnect_socket();
                }
        }
 
        /// This function should be called roughly once every 30 seconds.
-       /// It will send pings to each peer and disconnect those which did not respond to the last round of pings.
-
-       /// Will most likely call send_data on all of the registered descriptors, thus, be very careful with reentrancy issues!
-       pub fn timer_tick_occured(&self) {
+       /// It will send pings to each peer and disconnect those which did not respond to the last
+       /// round of pings.
+       ///
+       /// May call [`send_data`] on all [`SocketDescriptor`]s. Thus, be very careful with reentrancy
+       /// issues!
+       ///
+       /// [`send_data`]: SocketDescriptor::send_data
+       pub fn timer_tick_occurred(&self) {
                let mut peers_lock = self.peers.lock().unwrap();
                {
                        let peers = &mut *peers_lock;
-                       let peers_needing_send = &mut peers.peers_needing_send;
                        let node_id_to_descriptor = &mut peers.node_id_to_descriptor;
                        let peers = &mut peers.peers;
                        let mut descriptors_needing_disconnect = Vec::new();
 
                        peers.retain(|descriptor, peer| {
                                if peer.awaiting_pong {
-                                       peers_needing_send.remove(descriptor);
                                        descriptors_needing_disconnect.push(descriptor.clone());
                                        match peer.their_node_id {
                                                Some(node_id) => {
@@ -1233,7 +1420,7 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, L: Deref> PeerManager<D
                                        ponglen: 0,
                                        byteslen: 64,
                                };
-                               peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(&ping)));
+                               self.enqueue_message(peer, &ping);
 
                                let mut descriptor_clone = descriptor.clone();
                                self.do_attempt_write_data(&mut descriptor_clone, peer);
@@ -1259,9 +1446,9 @@ mod tests {
        use bitcoin::secp256k1::Secp256k1;
        use bitcoin::secp256k1::key::{SecretKey, PublicKey};
 
-       use std;
-       use std::sync::{Arc, Mutex};
-       use std::sync::atomic::Ordering;
+       use prelude::*;
+       use sync::{Arc, Mutex};
+       use core::sync::atomic::Ordering;
 
        #[derive(Clone)]
        struct FileDescriptor {
@@ -1274,8 +1461,8 @@ mod tests {
                }
        }
        impl Eq for FileDescriptor { }
-       impl std::hash::Hash for FileDescriptor {
-               fn hash<H: std::hash::Hasher>(&self, hasher: &mut H) {
+       impl core::hash::Hash for FileDescriptor {
+               fn hash<H: core::hash::Hasher>(&self, hasher: &mut H) {
                        self.fd.hash(hasher)
                }
        }
@@ -1331,7 +1518,9 @@ mod tests {
                let initial_data = peer_b.new_outbound_connection(a_id, fd_b.clone()).unwrap();
                peer_a.new_inbound_connection(fd_a.clone()).unwrap();
                assert_eq!(peer_a.read_event(&mut fd_a, &initial_data).unwrap(), false);
+               peer_a.process_events();
                assert_eq!(peer_b.read_event(&mut fd_b, &fd_a.outbound_data.lock().unwrap().split_off(0)).unwrap(), false);
+               peer_b.process_events();
                assert_eq!(peer_a.read_event(&mut fd_a, &fd_b.outbound_data.lock().unwrap().split_off(0)).unwrap(), false);
                (fd_a.clone(), fd_b.clone())
        }
@@ -1369,11 +1558,13 @@ mod tests {
                assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
 
                // peers[0] awaiting_pong is set to true, but the Peer is still connected
-               peers[0].timer_tick_occured();
+               peers[0].timer_tick_occurred();
+               peers[0].process_events();
                assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1);
 
-               // Since timer_tick_occured() is called again when awaiting_pong is true, all Peers are disconnected
-               peers[0].timer_tick_occured();
+               // Since timer_tick_occurred() is called again when awaiting_pong is true, all Peers are disconnected
+               peers[0].timer_tick_occurred();
+               peers[0].process_events();
                assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0);
        }
 
@@ -1394,7 +1585,9 @@ mod tests {
                let (mut fd_a, mut fd_b) = establish_connection(&peers[0], &peers[1]);
 
                // Make each peer to read the messages that the other peer just wrote to them.
+               peers[0].process_events();
                peers[1].read_event(&mut fd_b, &fd_a.outbound_data.lock().unwrap().split_off(0)).unwrap();
+               peers[1].process_events();
                peers[0].read_event(&mut fd_a, &fd_b.outbound_data.lock().unwrap().split_off(0)).unwrap();
 
                // Check that each peer has received the expected number of channel updates and channel