// This file is Copyright its original authors, visible in version control // history. // // This file is licensed under the Apache License, Version 2.0 or the MIT license // , at your option. // You may not use this file except in accordance with one or both of these // licenses. //! Top level peer message handling and socket handling logic lives here. //! //! Instead of actually servicing sockets ourselves we require that you implement the //! SocketDescriptor interface and use that to receive actions which you should perform on the //! socket, and call into PeerManager with bytes read from the socket. The PeerManager will then //! call into the provided message handlers (probably a ChannelManager and NetGraphmsgHandler) with messages //! they should handle, and encoding/sending response messages. use bitcoin::secp256k1::key::{SecretKey,PublicKey}; use ln::features::InitFeatures; use ln::msgs; use ln::msgs::{ChannelMessageHandler, LightningError, RoutingMessageHandler}; use ln::channelmanager::{SimpleArcChannelManager, SimpleRefChannelManager}; use util::ser::{VecWriter, Writeable}; use ln::peer_channel_encryptor::{PeerChannelEncryptor,NextNoiseStep}; use ln::wire; use ln::wire::Encode; use util::byte_utils; 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, mem}; use std::ops::Deref; 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 { Vec::new() } } impl RoutingMessageHandler for IgnoringMessageHandler { fn handle_node_announcement(&self, _msg: &msgs::NodeAnnouncement) -> Result { Ok(false) } fn handle_channel_announcement(&self, _msg: &msgs::ChannelAnnouncement) -> Result { Ok(false) } fn handle_channel_update(&self, _msg: &msgs::ChannelUpdate) -> Result { 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, Option)> { Vec::new() } fn get_next_node_announcements(&self, _starting_point: Option<&PublicKey>, _batch_amount: u8) -> Vec { 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> } 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 { 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 where CM::Target: ChannelMessageHandler, RM::Target: RoutingMessageHandler { /// A message handler which handles messages specific to channels. Usually this is just a /// ChannelManager object or a ErroringMessageHandler. 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 or an IgnoringMessageHandler. pub route_handler: RM, } /// Provides an object which can be used to send data to and which uniquely identifies a connection /// to a remote host. You will need to be able to generate multiple of these which meet Eq and /// implement Hash to meet the PeerManager API. /// /// 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(). 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. /// /// 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 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. 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. fn disconnect_socket(&mut self); } /// Error for PeerManager errors. If you get one of these, you must disconnect the socket and /// generate no further read_event/write_buffer_space_avail/socket_disconnected calls for the /// descriptor. #[derive(Clone)] pub struct PeerHandleError { /// Used to indicate that we probably can't make any future connections to this peer, implying /// we should go ahead and force-close any channels we have with it. pub no_connection_possible: bool, } impl fmt::Debug for PeerHandleError { fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> { formatter.write_str("Peer Sent Invalid Data") } } impl fmt::Display for PeerHandleError { fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> { formatter.write_str("Peer Sent Invalid Data") } } impl error::Error for PeerHandleError { fn description(&self) -> &str { "Peer Sent Invalid Data" } } enum InitSyncTracker{ NoSyncRequested, ChannelsSyncing(u64), NodesSyncing(PublicKey), } struct Peer { channel_encryptor: PeerChannelEncryptor, outbound: bool, their_node_id: Option, their_features: Option, pending_outbound_buffer: LinkedList>, pending_outbound_buffer_first_msg_offset: usize, awaiting_write_event: bool, pending_read_buffer: Vec, pending_read_buffer_pos: usize, pending_read_is_header: bool, sync_status: InitSyncTracker, awaiting_pong: bool, } impl Peer { /// Returns true if the channel announcements/updates for the given channel should be /// forwarded to this peer. /// If we are sending our routing table to this peer and we have not yet sent channel /// announcements/updates for the given channel_id then we will send it when we get to that /// point and we shouldn't send it yet to avoid sending duplicate updates. If we've already /// sent the old versions, we should send the update, and so return true here. fn should_forward_channel_announcement(&self, channel_id: u64)->bool{ match self.sync_status { InitSyncTracker::NoSyncRequested => true, InitSyncTracker::ChannelsSyncing(i) => i < channel_id, InitSyncTracker::NodesSyncing(_) => true, } } /// Similar to the above, but for node announcements indexed by node_id. fn should_forward_node_announcement(&self, node_id: PublicKey) -> bool { match self.sync_status { InitSyncTracker::NoSyncRequested => true, InitSyncTracker::ChannelsSyncing(_) => false, InitSyncTracker::NodesSyncing(pk) => pk < node_id, } } } struct PeerHolder { peers: HashMap, /// 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, /// Only add to this set when noise completes: node_id_to_descriptor: HashMap, } #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))] fn _check_usize_is_32_or_64() { // See below, less than 32 bit pointers may be unsafe here! unsafe { mem::transmute::<*const usize, [u8; 4]>(panic!()); } } /// SimpleArcPeerManager is useful when you need a PeerManager with a static lifetime, e.g. /// when you're using lightning-net-tokio (since tokio::spawn requires parameters with static /// 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 = PeerManager>, Arc, Arc>>, Arc>; /// 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 /// need a PeerManager with a static lifetime. You'll need a static lifetime in cases such as /// usage of lightning-net-tokio (since tokio::spawn requires parameters with static lifetimes). /// But if this is not necessary, using a reference is more efficient. Defining these type aliases /// 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, &'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. /// /// 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. pub struct PeerManager where CM::Target: ChannelMessageHandler, RM::Target: RoutingMessageHandler, L::Target: Logger { message_handler: MessageHandler, peers: Mutex>, our_node_secret: SecretKey, ephemeral_key_midstate: Sha256Engine, // Usize needs to be at least 32 bits to avoid overflowing both low and high. If usize is 64 // bits we will never realistically count into high: peer_counter_low: AtomicUsize, peer_counter_high: AtomicUsize, logger: L, } enum MessageHandlingError { PeerHandleError(PeerHandleError), LightningError(LightningError), } impl From for MessageHandlingError { fn from(error: PeerHandleError) -> Self { MessageHandlingError::PeerHandleError(error) } } impl From for MessageHandlingError { fn from(error: LightningError) -> Self { MessageHandlingError::LightningError(error) } } macro_rules! encode_msg { ($msg: expr) => {{ let mut buffer = VecWriter(Vec::new()); wire::write($msg, &mut buffer).unwrap(); buffer.0 }} } impl PeerManager 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 PeerManager 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) } } /// 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 PeerManager where CM::Target: ChannelMessageHandler, RM::Target: RoutingMessageHandler, L::Target: Logger { /// Constructs a new PeerManager with the given message handlers and node_id secret key /// ephemeral_random_data is used to derive per-connection ephemeral keys and must be /// cryptographically secure random bytes. pub fn new(message_handler: MessageHandler, our_node_secret: SecretKey, ephemeral_random_data: &[u8; 32], logger: L) -> Self { let mut ephemeral_key_midstate = Sha256::engine(); ephemeral_key_midstate.input(ephemeral_random_data); PeerManager { message_handler, peers: Mutex::new(PeerHolder { peers: HashMap::new(), peers_needing_send: HashSet::new(), node_id_to_descriptor: HashMap::new() }), our_node_secret, ephemeral_key_midstate, peer_counter_low: AtomicUsize::new(0), peer_counter_high: AtomicUsize::new(0), logger, } } /// Get the list of node ids for peers which have completed the initial handshake. /// /// For outbound connections, this will be the same as the their_node_id parameter passed in to /// new_outbound_connection, however entries will only appear once the initial handshake has /// completed and we are sure the remote peer has the private key for the given node_id. pub fn get_peer_node_ids(&self) -> Vec { let peers = self.peers.lock().unwrap(); peers.peers.values().filter_map(|p| { if !p.channel_encryptor.is_ready_for_encryption() || p.their_features.is_none() { return None; } p.their_node_id }).collect() } fn get_ephemeral_key(&self) -> SecretKey { let mut ephemeral_hash = self.ephemeral_key_midstate.clone(); let low = self.peer_counter_low.fetch_add(1, Ordering::AcqRel); let high = if low == 0 { self.peer_counter_high.fetch_add(1, Ordering::AcqRel) } else { self.peer_counter_high.load(Ordering::Acquire) }; ephemeral_hash.input(&byte_utils::le64_to_array(low as u64)); ephemeral_hash.input(&byte_utils::le64_to_array(high as u64)); SecretKey::from_slice(&Sha256::from_engine(ephemeral_hash).into_inner()).expect("You broke SHA-256!") } /// Indicates a new outbound connection has been established to a node with the given node_id. /// Note that if an Err is returned here you MUST NOT call socket_disconnected for the new /// descriptor but must disconnect the connection immediately. /// /// 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(). pub fn new_outbound_connection(&self, their_node_id: PublicKey, descriptor: Descriptor) -> Result, 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(); let pending_read_buffer = [0; 50].to_vec(); // Noise act two is 50 bytes 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, pending_outbound_buffer: LinkedList::new(), pending_outbound_buffer_first_msg_offset: 0, awaiting_write_event: false, pending_read_buffer, pending_read_buffer_pos: 0, pending_read_is_header: false, sync_status: InitSyncTracker::NoSyncRequested, awaiting_pong: false, }).is_some() { panic!("PeerManager driver duplicated descriptors!"); }; Ok(res) } /// Indicates a new inbound connection has been established. /// /// May refuse the connection by returning an Err, but will never write bytes to the remote end /// (outbound connector always speaks first). Note that if an Err is returned here you MUST NOT /// 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. 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 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, pending_outbound_buffer: LinkedList::new(), pending_outbound_buffer_first_msg_offset: 0, awaiting_write_event: false, pending_read_buffer, pending_read_buffer_pos: 0, pending_read_is_header: false, sync_status: InitSyncTracker::NoSyncRequested, awaiting_pong: false, }).is_some() { panic!("PeerManager driver duplicated descriptors!"); }; Ok(()) } 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 { 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 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); if let &Some(ref update_a) = update_a_option { encode_and_send_msg!(update_a); } if let &Some(ref update_b) = update_b_option { encode_and_send_msg!(update_b); } peer.sync_status = InitSyncTracker::ChannelsSyncing(announce.contents.short_channel_id + 1); } if all_messages.is_empty() || all_messages.len() != steps as usize { peer.sync_status = InitSyncTracker::ChannelsSyncing(0xffff_ffff_ffff_ffff); } }, InitSyncTracker::ChannelsSyncing(c) if c == 0xffff_ffff_ffff_ffff => { let steps = (MSG_BUFF_SIZE - 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); peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id); } if all_messages.is_empty() || all_messages.len() != steps as usize { peer.sync_status = InitSyncTracker::NoSyncRequested; } }, InitSyncTracker::ChannelsSyncing(_) => unreachable!(), InitSyncTracker::NodesSyncing(key) => { let steps = (MSG_BUFF_SIZE - 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); peer.sync_status = InitSyncTracker::NodesSyncing(msg.contents.node_id); } if all_messages.is_empty() || all_messages.len() != steps as usize { peer.sync_status = InitSyncTracker::NoSyncRequested; } }, } } if { let next_buff = match peer.pending_outbound_buffer.front() { None => return, Some(buff) => buff, }; let should_be_reading = peer.pending_outbound_buffer.len() < MSG_BUFF_SIZE; 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; if peer.pending_outbound_buffer_first_msg_offset == next_buff.len() { true } else { false } } { peer.pending_outbound_buffer_first_msg_offset = 0; peer.pending_outbound_buffer.pop_front(); } else { peer.awaiting_write_event = true; } } } /// Indicates that there is room to write data to the given socket descriptor. /// /// 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. 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"), Some(peer) => { peer.awaiting_write_event = false; self.do_attempt_write_data(descriptor, peer); } }; Ok(()) } /// Indicates that data was read from the given socket descriptor. /// /// 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. /// /// 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). /// /// Panics if the descriptor was not previously registered in a new_*_connection event. pub fn read_event(&self, peer_descriptor: &mut Descriptor, data: &[u8]) -> Result { match self.do_read_event(peer_descriptor, data) { Ok(res) => Ok(res), Err(e) => { self.disconnect_event_internal(peer_descriptor, e.no_connection_possible); Err(e) } } } /// Append a message to a peer's pending outbound/write buffer, and update the map of peers needing sends accordingly. fn enqueue_message(&self, peers_needing_send: &mut HashSet, peer: &mut Peer, descriptor: Descriptor, 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())); 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 { let pause_read = { let mut peers_lock = self.peers.lock().unwrap(); let peers = &mut *peers_lock; let pause_read = match peers.peers.get_mut(peer_descriptor) { None => panic!("Descriptor for read_event is not already known to PeerManager"), Some(peer) => { assert!(peer.pending_read_buffer.len() > 0); assert!(peer.pending_read_buffer.len() > peer.pending_read_buffer_pos); let mut read_pos = 0; while read_pos < data.len() { { let data_to_copy = cmp::min(peer.pending_read_buffer.len() - peer.pending_read_buffer_pos, data.len() - read_pos); peer.pending_read_buffer[peer.pending_read_buffer_pos..peer.pending_read_buffer_pos + data_to_copy].copy_from_slice(&data[read_pos..read_pos + data_to_copy]); read_pos += data_to_copy; peer.pending_read_buffer_pos += data_to_copy; } if peer.pending_read_buffer_pos == peer.pending_read_buffer.len() { peer.pending_read_buffer_pos = 0; macro_rules! try_potential_handleerror { ($thing: expr) => { match $thing { Ok(x) => x, Err(e) => { 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); return Err(PeerHandleError{ no_connection_possible: false }); }, msgs::ErrorAction::IgnoreError => { log_trace!(self.logger, "Got Err handling message, ignoring because {}", 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); continue; }, } } }; } } macro_rules! insert_node_id { () => { match peers.node_id_to_descriptor.entry(peer.their_node_id.unwrap()) { hash_map::Entry::Occupied(_) => { log_trace!(self.logger, "Got second connection with {}, closing", log_pubkey!(peer.their_node_id.unwrap())); peer.their_node_id = None; // Unset so that we don't generate a peer_disconnected event 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())); entry.insert(peer_descriptor.clone()) }, }; } } let next_step = peer.channel_encryptor.get_noise_step(); match next_step { NextNoiseStep::ActOne => { let act_two = try_potential_handleerror!(peer.channel_encryptor.process_act_one_with_keys(&peer.pending_read_buffer[..], &self.our_node_secret, self.get_ephemeral_key())).to_vec(); peer.pending_outbound_buffer.push_back(act_two); peer.pending_read_buffer = [0; 66].to_vec(); // act three is 66 bytes long }, NextNoiseStep::ActTwo => { let (act_three, their_node_id) = try_potential_handleerror!(peer.channel_encryptor.process_act_two(&peer.pending_read_buffer[..], &self.our_node_secret)); peer.pending_outbound_buffer.push_back(act_three.to_vec()); peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes 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(&mut peers.peers_needing_send, peer, peer_descriptor.clone(), &resp); }, NextNoiseStep::ActThree => { let their_node_id = try_potential_handleerror!(peer.channel_encryptor.process_act_three(&peer.pending_read_buffer[..])); peer.pending_read_buffer = [0; 18].to_vec(); // Message length header is 18 bytes peer.pending_read_is_header = true; peer.their_node_id = Some(their_node_id); insert_node_id!(); }, NextNoiseStep::NoiseComplete => { if peer.pending_read_is_header { let msg_len = try_potential_handleerror!(peer.channel_encryptor.decrypt_length_header(&peer.pending_read_buffer[..])); peer.pending_read_buffer = Vec::with_capacity(msg_len as usize + 16); peer.pending_read_buffer.resize(msg_len as usize + 16, 0); if msg_len < 2 { // Need at least the message type tag return Err(PeerHandleError{ no_connection_possible: false }); } peer.pending_read_is_header = false; } else { let msg_data = try_potential_handleerror!(peer.channel_encryptor.decrypt_message(&peer.pending_read_buffer[..])); assert!(msg_data.len() >= 2); // Reset read buffer peer.pending_read_buffer = [0; 18].to_vec(); peer.pending_read_is_header = true; let mut reader = ::std::io::Cursor::new(&msg_data[..]); let message_result = wire::read(&mut reader); let message = match message_result { Ok(x) => x, Err(e) => { 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!"); continue; } msgs::DecodeError::InvalidValue => { log_debug!(self.logger, "Got an invalid value while deserializing message"); return Err(PeerHandleError { no_connection_possible: false }); } msgs::DecodeError::ShortRead => { log_debug!(self.logger, "Deserialization failed due to shortness of message"); return Err(PeerHandleError { no_connection_possible: false }); } msgs::DecodeError::BadLengthDescriptor => return Err(PeerHandleError { no_connection_possible: false }), msgs::DecodeError::Io(_) => return Err(PeerHandleError { no_connection_possible: false }), } } }; if let Err(handling_error) = self.handle_message(&mut peers.peers_needing_send, peer, peer_descriptor.clone(), message){ match handling_error { MessageHandlingError::PeerHandleError(e) => { return Err(e) }, MessageHandlingError::LightningError(e) => { try_potential_handleerror!(Err(e)); }, } } } } } } } self.do_attempt_write_data(peer_descriptor, peer); peer.pending_outbound_buffer.len() > 10 // pause_read } }; pause_read }; Ok(pause_read) } /// 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, 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())); // 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())); return Err(PeerHandleError{ no_connection_possible: false }.into()); } 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"); return Err(PeerHandleError{ no_connection_possible: true }.into()); } if peer.their_features.is_some() { return Err(PeerHandleError{ no_connection_possible: false }.into()); } log_info!( self.logger, "Received peer Init message: data_loss_protect: {}, initial_routing_sync: {}, upfront_shutdown_script: {}, gossip_queries: {}, static_remote_key: {}, unknown flags (local and global): {}", if msg.features.supports_data_loss_protect() { "supported" } else { "not supported"}, if msg.features.initial_routing_sync() { "requested" } else { "not requested" }, if msg.features.supports_upfront_shutdown_script() { "supported" } else { "not supported"}, if msg.features.supports_gossip_queries() { "supported" } else { "not supported" }, if msg.features.supports_static_remote_key() { "supported" } else { "not supported"}, if msg.features.supports_unknown_bits() { "present" } else { "none" } ); 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); peer.their_features = Some(msg.features); }, wire::Message::Error(msg) => { let mut data_is_printable = true; for b in msg.data.bytes() { if b < 32 || b > 126 { data_is_printable = false; break; } } if data_is_printable { log_debug!(self.logger, "Got Err message from {}: {}", log_pubkey!(peer.their_node_id.unwrap()), msg.data); } else { log_debug!(self.logger, "Got Err message from {} with non-ASCII error message", log_pubkey!(peer.their_node_id.unwrap())); } self.message_handler.chan_handler.handle_error(&peer.their_node_id.unwrap(), &msg); if msg.channel_id == [0; 32] { return Err(PeerHandleError{ no_connection_possible: true }.into()); } }, 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); } }, wire::Message::Pong(_msg) => { peer.awaiting_pong = false; }, // Channel messages: wire::Message::OpenChannel(msg) => { self.message_handler.chan_handler.handle_open_channel(&peer.their_node_id.unwrap(), peer.their_features.clone().unwrap(), &msg); }, wire::Message::AcceptChannel(msg) => { self.message_handler.chan_handler.handle_accept_channel(&peer.their_node_id.unwrap(), peer.their_features.clone().unwrap(), &msg); }, wire::Message::FundingCreated(msg) => { self.message_handler.chan_handler.handle_funding_created(&peer.their_node_id.unwrap(), &msg); }, wire::Message::FundingSigned(msg) => { self.message_handler.chan_handler.handle_funding_signed(&peer.their_node_id.unwrap(), &msg); }, wire::Message::FundingLocked(msg) => { self.message_handler.chan_handler.handle_funding_locked(&peer.their_node_id.unwrap(), &msg); }, wire::Message::Shutdown(msg) => { self.message_handler.chan_handler.handle_shutdown(&peer.their_node_id.unwrap(), peer.their_features.as_ref().unwrap(), &msg); }, wire::Message::ClosingSigned(msg) => { self.message_handler.chan_handler.handle_closing_signed(&peer.their_node_id.unwrap(), &msg); }, // Commitment messages: wire::Message::UpdateAddHTLC(msg) => { self.message_handler.chan_handler.handle_update_add_htlc(&peer.their_node_id.unwrap(), &msg); }, wire::Message::UpdateFulfillHTLC(msg) => { self.message_handler.chan_handler.handle_update_fulfill_htlc(&peer.their_node_id.unwrap(), &msg); }, wire::Message::UpdateFailHTLC(msg) => { self.message_handler.chan_handler.handle_update_fail_htlc(&peer.their_node_id.unwrap(), &msg); }, wire::Message::UpdateFailMalformedHTLC(msg) => { self.message_handler.chan_handler.handle_update_fail_malformed_htlc(&peer.their_node_id.unwrap(), &msg); }, wire::Message::CommitmentSigned(msg) => { self.message_handler.chan_handler.handle_commitment_signed(&peer.their_node_id.unwrap(), &msg); }, wire::Message::RevokeAndACK(msg) => { self.message_handler.chan_handler.handle_revoke_and_ack(&peer.their_node_id.unwrap(), &msg); }, wire::Message::UpdateFee(msg) => { self.message_handler.chan_handler.handle_update_fee(&peer.their_node_id.unwrap(), &msg); }, wire::Message::ChannelReestablish(msg) => { self.message_handler.chan_handler.handle_channel_reestablish(&peer.their_node_id.unwrap(), &msg); }, // Routing messages: wire::Message::AnnouncementSignatures(msg) => { 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! } }, 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! } }, wire::Message::ChannelUpdate(msg) => { self.message_handler.chan_handler.handle_channel_update(&peer.their_node_id.unwrap(), &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! } }, wire::Message::QueryShortChannelIds(msg) => { self.message_handler.route_handler.handle_query_short_channel_ids(&peer.their_node_id.unwrap(), msg)?; }, wire::Message::ReplyShortChannelIdsEnd(msg) => { self.message_handler.route_handler.handle_reply_short_channel_ids_end(&peer.their_node_id.unwrap(), msg)?; }, wire::Message::QueryChannelRange(msg) => { self.message_handler.route_handler.handle_query_channel_range(&peer.their_node_id.unwrap(), msg)?; }, wire::Message::ReplyChannelRange(msg) => { self.message_handler.route_handler.handle_reply_channel_range(&peer.their_node_id.unwrap(), msg)?; }, wire::Message::GossipTimestampFilter(_msg) => { // TODO: handle message }, // Unknown messages: wire::Message::Unknown(msg_type) if msg_type.is_even() => { log_debug!(self.logger, "Received unknown even message of type {}, disconnecting peer!", msg_type); // Fail the channel if message is an even, unknown type as per BOLT #1. return Err(PeerHandleError{ no_connection_possible: true }.into()); }, wire::Message::Unknown(msg_type) => { log_trace!(self.logger, "Received unknown odd message of type {}, ignoring", msg_type); } }; Ok(()) } /// 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). 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 peers = &mut *peers_lock; for event in events_generated.drain(..) { macro_rules! get_peer_for_forwarding { ($node_id: expr, $handle_no_such_peer: block) => { { let descriptor = match peers.node_id_to_descriptor.get($node_id) { Some(descriptor) => descriptor.clone(), 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_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); }, MessageSendEvent::SendOpenChannel { ref node_id, ref msg } => { log_trace!(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); }, MessageSendEvent::SendFundingCreated { ref node_id, ref msg } => { log_trace!(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); }, MessageSendEvent::SendFundingSigned { ref node_id, ref msg } => { log_trace!(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); }, MessageSendEvent::SendFundingLocked { ref node_id, ref msg } => { log_trace!(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); }, MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => { log_trace!(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); }, 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_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 }); for msg in update_add_htlcs { peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg))); } for msg in update_fulfill_htlcs { peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg))); } for msg in update_fail_htlcs { peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg))); } for msg in update_fail_malformed_htlcs { peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg))); } if let &Some(ref msg) = update_fee { peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg))); } peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(commitment_signed))); self.do_attempt_write_data(&mut descriptor, peer); }, MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => { log_trace!(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); }, MessageSendEvent::SendClosingSigned { ref node_id, ref msg } => { log_trace!(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); }, MessageSendEvent::SendShutdown { ref node_id, ref msg } => { log_trace!(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); }, MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => { log_trace!(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); }, 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::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::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::PaymentFailureNetworkUpdate { ref update } => { self.message_handler.route_handler.handle_htlc_fail_channel_update(update); }, MessageSendEvent::HandleError { ref node_id, ref action } => { 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))); // 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); } else { log_trace!(self.logger, "Handling DisconnectPeer HandleError event in peer_handler for node {} with no message", log_pubkey!(node_id)); } } descriptor.disconnect_socket(); self.message_handler.chan_handler.peer_disconnected(&node_id, false); } }, msgs::ErrorAction::IgnoreError => {}, 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); }, } }, 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); }, 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); } 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); 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); } } } 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!"), } } } } /// 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"), Some(peer) => { match peer.their_node_id { Some(node_id) => { peers.node_id_to_descriptor.remove(&node_id); self.message_handler.chan_handler.peer_disconnected(&node_id, no_connection_possible); }, None => {} } } }; } /// Disconnect a peer given its node id. /// /// 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. 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_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) => { log_trace!(self.logger, "Disconnecting peer with id {} due to ping timeout", node_id); node_id_to_descriptor.remove(&node_id); self.message_handler.chan_handler.peer_disconnected(&node_id, false); } None => { // This can't actually happen as we should have hit // is_ready_for_encryption() previously on this same peer. unreachable!(); }, } return false; } if !peer.channel_encryptor.is_ready_for_encryption() { // The peer needs to complete its handshake before we can exchange messages return true; } let ping = msgs::Ping { ponglen: 0, byteslen: 64, }; peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(&ping))); let mut descriptor_clone = descriptor.clone(); self.do_attempt_write_data(&mut descriptor_clone, peer); peer.awaiting_pong = true; true }); for mut descriptor in descriptors_needing_disconnect.drain(..) { descriptor.disconnect_socket(); } } } } #[cfg(test)] mod tests { use ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor}; use ln::msgs; use util::events; use util::test_utils; use bitcoin::secp256k1::Secp256k1; use bitcoin::secp256k1::key::{SecretKey, PublicKey}; use std; use std::sync::{Arc, Mutex}; use std::sync::atomic::Ordering; #[derive(Clone)] struct FileDescriptor { fd: u16, outbound_data: Arc>>, } impl PartialEq for FileDescriptor { fn eq(&self, other: &Self) -> bool { self.fd == other.fd } } impl Eq for FileDescriptor { } impl std::hash::Hash for FileDescriptor { fn hash(&self, hasher: &mut H) { self.fd.hash(hasher) } } impl SocketDescriptor for FileDescriptor { fn send_data(&mut self, data: &[u8], _resume_read: bool) -> usize { self.outbound_data.lock().unwrap().extend_from_slice(data); data.len() } fn disconnect_socket(&mut self) {} } struct PeerManagerCfg { chan_handler: test_utils::TestChannelMessageHandler, routing_handler: test_utils::TestRoutingMessageHandler, logger: test_utils::TestLogger, } fn create_peermgr_cfgs(peer_count: usize) -> Vec { let mut cfgs = Vec::new(); for _ in 0..peer_count { cfgs.push( PeerManagerCfg{ chan_handler: test_utils::TestChannelMessageHandler::new(), logger: test_utils::TestLogger::new(), routing_handler: test_utils::TestRoutingMessageHandler::new(), } ); } cfgs } fn create_network<'a>(peer_count: usize, cfgs: &'a Vec) -> Vec> { let mut peers = Vec::new(); for i in 0..peer_count { let node_secret = SecretKey::from_slice(&[42 + i as u8; 32]).unwrap(); let ephemeral_bytes = [i as u8; 32]; let msg_handler = MessageHandler { chan_handler: &cfgs[i].chan_handler, route_handler: &cfgs[i].routing_handler }; let peer = PeerManager::new(msg_handler, node_secret, &ephemeral_bytes, &cfgs[i].logger); peers.push(peer); } peers } fn establish_connection<'a>(peer_a: &PeerManager, peer_b: &PeerManager) -> (FileDescriptor, FileDescriptor) { let secp_ctx = Secp256k1::new(); let a_id = PublicKey::from_secret_key(&secp_ctx, &peer_a.our_node_secret); let mut fd_a = FileDescriptor { fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())) }; let mut fd_b = FileDescriptor { fd: 1, outbound_data: Arc::new(Mutex::new(Vec::new())) }; 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); assert_eq!(peer_b.read_event(&mut fd_b, &fd_a.outbound_data.lock().unwrap().split_off(0)).unwrap(), false); 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()) } #[test] fn test_disconnect_peer() { // Simple test which builds a network of PeerManager, connects and brings them to NoiseState::Finished and // push a DisconnectPeer event to remove the node flagged by id let cfgs = create_peermgr_cfgs(2); let chan_handler = test_utils::TestChannelMessageHandler::new(); let mut peers = create_network(2, &cfgs); establish_connection(&peers[0], &peers[1]); assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1); let secp_ctx = Secp256k1::new(); let their_id = PublicKey::from_secret_key(&secp_ctx, &peers[1].our_node_secret); chan_handler.pending_events.lock().unwrap().push(events::MessageSendEvent::HandleError { node_id: their_id, action: msgs::ErrorAction::DisconnectPeer { msg: None }, }); assert_eq!(chan_handler.pending_events.lock().unwrap().len(), 1); peers[0].message_handler.chan_handler = &chan_handler; peers[0].process_events(); assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0); } #[test] fn test_timer_tick_occurred() { // Create peers, a vector of two peer managers, perform initial set up and check that peers[0] has one Peer. let cfgs = create_peermgr_cfgs(2); let peers = create_network(2, &cfgs); establish_connection(&peers[0], &peers[1]); 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_occurred(); assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 1); // Since timer_tick_occurred() is called again when awaiting_pong is true, all Peers are disconnected peers[0].timer_tick_occurred(); assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0); } #[test] fn test_do_attempt_write_data() { // Create 2 peers with custom TestRoutingMessageHandlers and connect them. let cfgs = create_peermgr_cfgs(2); cfgs[0].routing_handler.request_full_sync.store(true, Ordering::Release); cfgs[1].routing_handler.request_full_sync.store(true, Ordering::Release); let peers = create_network(2, &cfgs); // By calling establish_connect, we trigger do_attempt_write_data between // the peers. Previously this function would mistakenly enter an infinite loop // when there were more channel messages available than could fit into a peer's // buffer. This issue would now be detected by this test (because we use custom // RoutingMessageHandlers that intentionally return more channel messages // than can fit into a peer's buffer). 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[1].read_event(&mut fd_b, &fd_a.outbound_data.lock().unwrap().split_off(0)).unwrap(); 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 // announcements. assert_eq!(cfgs[0].routing_handler.chan_upds_recvd.load(Ordering::Acquire), 100); assert_eq!(cfgs[0].routing_handler.chan_anns_recvd.load(Ordering::Acquire), 50); assert_eq!(cfgs[1].routing_handler.chan_upds_recvd.load(Ordering::Acquire), 100); assert_eq!(cfgs[1].routing_handler.chan_anns_recvd.load(Ordering::Acquire), 50); } }