//! 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 Router) with messages //! they should handle, and encoding/sending response messages. use secp256k1::key::{SecretKey,PublicKey}; use ln::msgs; use util::ser::{Writeable, Writer, Readable}; use ln::peer_channel_encryptor::{PeerChannelEncryptor,NextNoiseStep}; use util::byte_utils; use util::events::{MessageSendEvent}; use util::logger::Logger; 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}; /// Provides references to trait impls which handle different types of messages. pub struct MessageHandler { /// A message handler which handles messages specific to channels. Usually this is just a /// ChannelManager object. pub chan_handler: Arc, /// A message handler which handles messages updating our knowledge of the network channel /// graph. Usually this is just a Router object. pub route_handler: Arc, } /// 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 close() itself, be /// careful to ensure you don't have races whereby you might register a new connection with an fd /// the same as a yet-to-be-disconnect_event()-ed. pub trait SocketDescriptor : cmp::Eq + hash::Hash + Clone { /// Attempts to send some data from the given Vec starting at the given offset 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, a disconnect_event must still fire and further write /// attempts may occur until that time. /// /// If the returned size is smaller than data.len() - write_offset, 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: &Vec, write_offset: usize, resume_read: bool) -> usize; /// Disconnect the socket pointed to by this SocketDescriptor. Once this function returns, no /// more calls to write_event, read_event or disconnect_event may be made with this descriptor. /// No disconnect_event should be generated as a result of this call, though obviously races /// may occur whereby disconnect_socket is called after a call to disconnect_event but prior to /// that event completing. 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/write_events for the descriptor, only triggering a single /// disconnect_event (unless it was provided in response to a new_*_connection event, in which case /// no such disconnect_event must be generated and the socket be silently disconencted). 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. 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_global_features: Option, their_local_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, } impl Peer { /// Returns true if the 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(&self, channel_id: u64)->bool{ match self.sync_status { InitSyncTracker::NoSyncRequested => true, InitSyncTracker::ChannelsSyncing(i) => i < channel_id, InitSyncTracker::NodesSyncing(_) => true, } } } 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, } struct MutPeerHolder<'a, Descriptor: SocketDescriptor + 'a> { peers: &'a mut HashMap, peers_needing_send: &'a mut HashSet, node_id_to_descriptor: &'a mut HashMap, } impl PeerHolder { fn borrow_parts(&mut self) -> MutPeerHolder { MutPeerHolder { peers: &mut self.peers, peers_needing_send: &mut self.peers_needing_send, node_id_to_descriptor: &mut self.node_id_to_descriptor, } } } /// A PeerManager manages a set of peers, described by their SocketDescriptor and marshalls socket /// events into messages which it passes on to its MessageHandlers. pub struct PeerManager { message_handler: MessageHandler, peers: Mutex>, our_node_secret: SecretKey, initial_syncs_sent: AtomicUsize, logger: Arc, } struct VecWriter(Vec); impl Writer for VecWriter { fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error> { self.0.extend_from_slice(buf); Ok(()) } fn size_hint(&mut self, size: usize) { self.0.reserve_exact(size); } } macro_rules! encode_msg { ($msg: expr, $msg_code: expr) => {{ let mut msg = VecWriter(Vec::new()); ($msg_code as u16).write(&mut msg).unwrap(); $msg.write(&mut msg).unwrap(); msg.0 }} } //TODO: Really should do something smarter for this const INITIAL_SYNCS_TO_SEND: usize = 5; /// Manages and reacts to connection events. You probably want to use file descriptors as PeerIds. /// PeerIds may repeat, but only after disconnect_event() has been called. impl PeerManager { /// Constructs a new PeerManager with the given message handlers and node_id secret key pub fn new(message_handler: MessageHandler, our_node_secret: SecretKey, logger: Arc) -> PeerManager { PeerManager { message_handler: message_handler, peers: Mutex::new(PeerHolder { peers: HashMap::new(), peers_needing_send: HashSet::new(), node_id_to_descriptor: HashMap::new() }), our_node_secret: our_node_secret, initial_syncs_sent: 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_global_features.is_none() { return None; } p.their_node_id }).collect() } /// 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 disconnect_event 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 has a /// disconnect_event. 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()); 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_global_features: None, their_local_features: None, pending_outbound_buffer: LinkedList::new(), pending_outbound_buffer_first_msg_offset: 0, awaiting_write_event: false, pending_read_buffer: pending_read_buffer, pending_read_buffer_pos: 0, pending_read_is_header: false, sync_status: InitSyncTracker::NoSyncRequested, }).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 disconnect_event for the new descriptor but must disconnect the connection /// immediately. /// /// Panics if descriptor is duplicative with some other descriptor which has not yet has a /// disconnect_event. 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_global_features: None, their_local_features: None, pending_outbound_buffer: LinkedList::new(), pending_outbound_buffer_first_msg_offset: 0, awaiting_write_event: false, pending_read_buffer: pending_read_buffer, pending_read_buffer_pos: 0, pending_read_is_header: false, sync_status: InitSyncTracker::NoSyncRequested, }).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, $msg_code: expr) => { { log_trace!(self, "Encoding and sending sync update message of type {} to {}", $msg_code, log_pubkey!(peer.their_node_id.unwrap())); peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!($msg, $msg_code)[..])); } } } 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(0, steps); for &(ref announce, ref update_a, ref update_b) in all_messages.iter() { encode_and_send_msg!(announce, 256); encode_and_send_msg!(update_a, 258); encode_and_send_msg!(update_b, 258); 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, 256); 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, 256); 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 data_sent = descriptor.send_data(next_buff, peer.pending_outbound_buffer_first_msg_offset, 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_event in case a write did not fully complete must still /// hold - be ready to call write_event 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_event(&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 write_event 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: Vec) -> 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) } } } fn do_read_event(&self, peer_descriptor: &mut Descriptor, data: Vec) -> Result { let pause_read = { let mut peers_lock = self.peers.lock().unwrap(); let peers = peers_lock.borrow_parts(); 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! encode_and_send_msg { ($msg: expr, $msg_code: expr) => { { log_trace!(self, "Encoding and sending message of type {} to {}", $msg_code, log_pubkey!(peer.their_node_id.unwrap())); peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!($msg, $msg_code)[..])); peers.peers_needing_send.insert(peer_descriptor.clone()); } } } macro_rules! try_potential_handleerror { ($thing: expr) => { match $thing { Ok(x) => x, Err(e) => { if let Some(action) = e.action { match action { msgs::ErrorAction::DisconnectPeer { msg: _ } => { //TODO: Try to push msg log_trace!(self, "Got Err handling message, disconnecting peer because {}", e.err); return Err(PeerHandleError{ no_connection_possible: false }); }, msgs::ErrorAction::IgnoreError => { log_trace!(self, "Got Err handling message, ignoring because {}", e.err); continue; }, msgs::ErrorAction::SendErrorMessage { msg } => { log_trace!(self, "Got Err handling message, sending Error message because {}", e.err); encode_and_send_msg!(msg, 17); continue; }, } } else { log_debug!(self, "Got Err handling message, action not yet filled in: {}", e.err); return Err(PeerHandleError{ no_connection_possible: false }); } } }; } } macro_rules! try_potential_decodeerror { ($thing: expr) => { match $thing { Ok(x) => x, Err(e) => { match e { msgs::DecodeError::UnknownVersion => return Err(PeerHandleError{ no_connection_possible: false }), msgs::DecodeError::UnknownRequiredFeature => { log_debug!(self, "Got a channel/node announcement with an known required feature flag, you may want to udpate!"); continue; }, msgs::DecodeError::InvalidValue => return Err(PeerHandleError{ no_connection_possible: false }), msgs::DecodeError::ShortRead => return Err(PeerHandleError{ no_connection_possible: false }), msgs::DecodeError::ExtraAddressesPerType => { log_debug!(self, "Error decoding message, ignoring due to lnd spec incompatibility. See https://github.com/lightningnetwork/lnd/issues/1407"); continue; }, msgs::DecodeError::BadLengthDescriptor => return Err(PeerHandleError{ no_connection_possible: false }), msgs::DecodeError::Io(_) => return Err(PeerHandleError{ no_connection_possible: false }), } } }; } } macro_rules! insert_node_id { () => { match peers.node_id_to_descriptor.entry(peer.their_node_id.unwrap()) { hash_map::Entry::Occupied(_) => { log_trace!(self, "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, "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_key(&peer.pending_read_buffer[..], &self.our_node_secret)).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 mut local_features = msgs::LocalFeatures::new(); if self.initial_syncs_sent.load(Ordering::Acquire) < INITIAL_SYNCS_TO_SEND { self.initial_syncs_sent.fetch_add(1, Ordering::AcqRel); local_features.set_initial_routing_sync(); } encode_and_send_msg!(msgs::Init { global_features: msgs::GlobalFeatures::new(), local_features, }, 16); }, 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 msg_type = byte_utils::slice_to_be16(&msg_data[0..2]); log_trace!(self, "Received message of type {} from {}", msg_type, log_pubkey!(peer.their_node_id.unwrap())); if msg_type != 16 && peer.their_global_features.is_none() { // Need an init message as first message log_trace!(self, "Peer {} sent non-Init first message", log_pubkey!(peer.their_node_id.unwrap())); return Err(PeerHandleError{ no_connection_possible: false }); } let mut reader = ::std::io::Cursor::new(&msg_data[2..]); match msg_type { // Connection control: 16 => { let msg = try_potential_decodeerror!(msgs::Init::read(&mut reader)); if msg.global_features.requires_unknown_bits() { log_info!(self, "Peer global features required unknown version bits"); return Err(PeerHandleError{ no_connection_possible: true }); } if msg.local_features.requires_unknown_bits() { log_info!(self, "Peer local features required unknown version bits"); return Err(PeerHandleError{ no_connection_possible: true }); } if msg.local_features.requires_data_loss_protect() { log_info!(self, "Peer local features required data_loss_protect"); return Err(PeerHandleError{ no_connection_possible: true }); } if msg.local_features.requires_upfront_shutdown_script() { log_info!(self, "Peer local features required upfront_shutdown_script"); return Err(PeerHandleError{ no_connection_possible: true }); } if peer.their_global_features.is_some() { return Err(PeerHandleError{ no_connection_possible: false }); } log_info!(self, "Received peer Init message: data_loss_protect: {}, initial_routing_sync: {}, upfront_shutdown_script: {}, unkown local flags: {}, unknown global flags: {}", if msg.local_features.supports_data_loss_protect() { "supported" } else { "not supported"}, if msg.local_features.initial_routing_sync() { "requested" } else { "not requested" }, if msg.local_features.supports_upfront_shutdown_script() { "supported" } else { "not supported"}, if msg.local_features.supports_unknown_bits() { "present" } else { "none" }, if msg.global_features.supports_unknown_bits() { "present" } else { "none" }); if msg.local_features.initial_routing_sync() { peer.sync_status = InitSyncTracker::ChannelsSyncing(0); peers.peers_needing_send.insert(peer_descriptor.clone()); } peer.their_global_features = Some(msg.global_features); peer.their_local_features = Some(msg.local_features); if !peer.outbound { let mut local_features = msgs::LocalFeatures::new(); if self.initial_syncs_sent.load(Ordering::Acquire) < INITIAL_SYNCS_TO_SEND { self.initial_syncs_sent.fetch_add(1, Ordering::AcqRel); local_features.set_initial_routing_sync(); } encode_and_send_msg!(msgs::Init { global_features: msgs::GlobalFeatures::new(), local_features, }, 16); } self.message_handler.chan_handler.peer_connected(&peer.their_node_id.unwrap()); }, 17 => { let msg = try_potential_decodeerror!(msgs::ErrorMessage::read(&mut reader)); 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, "Got Err message from {}: {}", log_pubkey!(peer.their_node_id.unwrap()), msg.data); } else { log_debug!(self, "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 }); } }, 18 => { let msg = try_potential_decodeerror!(msgs::Ping::read(&mut reader)); if msg.ponglen < 65532 { let resp = msgs::Pong { byteslen: msg.ponglen }; encode_and_send_msg!(resp, 19); } }, 19 => { try_potential_decodeerror!(msgs::Pong::read(&mut reader)); }, // Channel control: 32 => { let msg = try_potential_decodeerror!(msgs::OpenChannel::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_open_channel(&peer.their_node_id.unwrap(), &msg)); }, 33 => { let msg = try_potential_decodeerror!(msgs::AcceptChannel::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_accept_channel(&peer.their_node_id.unwrap(), &msg)); }, 34 => { let msg = try_potential_decodeerror!(msgs::FundingCreated::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_funding_created(&peer.their_node_id.unwrap(), &msg)); }, 35 => { let msg = try_potential_decodeerror!(msgs::FundingSigned::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_funding_signed(&peer.their_node_id.unwrap(), &msg)); }, 36 => { let msg = try_potential_decodeerror!(msgs::FundingLocked::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_funding_locked(&peer.their_node_id.unwrap(), &msg)); }, 38 => { let msg = try_potential_decodeerror!(msgs::Shutdown::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_shutdown(&peer.their_node_id.unwrap(), &msg)); }, 39 => { let msg = try_potential_decodeerror!(msgs::ClosingSigned::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_closing_signed(&peer.their_node_id.unwrap(), &msg)); }, 128 => { let msg = try_potential_decodeerror!(msgs::UpdateAddHTLC::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_update_add_htlc(&peer.their_node_id.unwrap(), &msg)); }, 130 => { let msg = try_potential_decodeerror!(msgs::UpdateFulfillHTLC::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_update_fulfill_htlc(&peer.their_node_id.unwrap(), &msg)); }, 131 => { let msg = try_potential_decodeerror!(msgs::UpdateFailHTLC::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_update_fail_htlc(&peer.their_node_id.unwrap(), &msg)); }, 135 => { let msg = try_potential_decodeerror!(msgs::UpdateFailMalformedHTLC::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_update_fail_malformed_htlc(&peer.their_node_id.unwrap(), &msg)); }, 132 => { let msg = try_potential_decodeerror!(msgs::CommitmentSigned::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_commitment_signed(&peer.their_node_id.unwrap(), &msg)); }, 133 => { let msg = try_potential_decodeerror!(msgs::RevokeAndACK::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_revoke_and_ack(&peer.their_node_id.unwrap(), &msg)); }, 134 => { let msg = try_potential_decodeerror!(msgs::UpdateFee::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_update_fee(&peer.their_node_id.unwrap(), &msg)); }, 136 => { let msg = try_potential_decodeerror!(msgs::ChannelReestablish::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_channel_reestablish(&peer.their_node_id.unwrap(), &msg)); }, // Routing control: 259 => { let msg = try_potential_decodeerror!(msgs::AnnouncementSignatures::read(&mut reader)); try_potential_handleerror!(self.message_handler.chan_handler.handle_announcement_signatures(&peer.their_node_id.unwrap(), &msg)); }, 256 => { let msg = try_potential_decodeerror!(msgs::ChannelAnnouncement::read(&mut reader)); let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_announcement(&msg)); if should_forward { // TODO: forward msg along to all our other peers! } }, 257 => { let msg = try_potential_decodeerror!(msgs::NodeAnnouncement::read(&mut reader)); let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_node_announcement(&msg)); if should_forward { // TODO: forward msg along to all our other peers! } }, 258 => { let msg = try_potential_decodeerror!(msgs::ChannelUpdate::read(&mut reader)); let should_forward = try_potential_handleerror!(self.message_handler.route_handler.handle_channel_update(&msg)); if should_forward { // TODO: forward msg along to all our other peers! } }, _ => { if (msg_type & 1) == 0 { return Err(PeerHandleError{ no_connection_possible: true }); } }, } } } } } } self.do_attempt_write_data(peer_descriptor, peer); peer.pending_outbound_buffer.len() > 10 // pause_read } }; pause_read }; Ok(pause_read) } /// 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 events_generated = self.message_handler.chan_handler.get_and_clear_pending_msg_events(); let mut peers_lock = self.peers.lock().unwrap(); let peers = peers_lock.borrow_parts(); 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_global_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, "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, 33))); self.do_attempt_write_data(&mut descriptor, peer); }, MessageSendEvent::SendOpenChannel { ref node_id, ref msg } => { log_trace!(self, "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, 32))); self.do_attempt_write_data(&mut descriptor, peer); }, MessageSendEvent::SendFundingCreated { ref node_id, ref msg } => { log_trace!(self, "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, 34))); self.do_attempt_write_data(&mut descriptor, peer); }, MessageSendEvent::SendFundingSigned { ref node_id, ref msg } => { log_trace!(self, "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, 35))); self.do_attempt_write_data(&mut descriptor, peer); }, MessageSendEvent::SendFundingLocked { ref node_id, ref msg } => { log_trace!(self, "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, 36))); self.do_attempt_write_data(&mut descriptor, peer); }, MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => { log_trace!(self, "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, 259))); 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, "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, 128))); } for msg in update_fulfill_htlcs { peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 130))); } for msg in update_fail_htlcs { peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 131))); } for msg in update_fail_malformed_htlcs { peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 135))); } if let &Some(ref msg) = update_fee { peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg, 134))); } peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(commitment_signed, 132))); self.do_attempt_write_data(&mut descriptor, peer); }, MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => { log_trace!(self, "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, 133))); self.do_attempt_write_data(&mut descriptor, peer); }, MessageSendEvent::SendClosingSigned { ref node_id, ref msg } => { log_trace!(self, "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, 39))); self.do_attempt_write_data(&mut descriptor, peer); }, MessageSendEvent::SendShutdown { ref node_id, ref msg } => { log_trace!(self, "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, 38))); self.do_attempt_write_data(&mut descriptor, peer); }, MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => { log_trace!(self, "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, 136))); self.do_attempt_write_data(&mut descriptor, peer); }, MessageSendEvent::BroadcastChannelAnnouncement { ref msg, ref update_msg } => { log_trace!(self, "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, 256); let encoded_update_msg = encode_msg!(update_msg, 258); for (ref descriptor, ref mut peer) in peers.peers.iter_mut() { if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_global_features.is_none() || !peer.should_forward_channel(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::BroadcastChannelUpdate { ref msg } => { log_trace!(self, "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, 258); for (ref descriptor, ref mut peer) in peers.peers.iter_mut() { if !peer.channel_encryptor.is_ready_for_encryption() || peer.their_global_features.is_none() || !peer.should_forward_channel(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 } => { if let Some(ref action) = *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, "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, 17))); // 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, "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, "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, 17))); self.do_attempt_write_data(&mut descriptor, peer); }, } } else { log_error!(self, "Got no-action HandleError Event in peer_handler for node {}, no such events should ever be generated!", log_pubkey!(node_id)); } } } } 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 be called even if a PeerHandleError was given for a read_event or write_event, /// but must NOT be called if a PeerHandleError was provided out of a new_\*\_connection event! /// /// Panics if the descriptor was not previously registered in a successful new_*_connection event. pub fn disconnect_event(&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 => {} } } }; } } #[cfg(test)] mod tests { use ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor}; use ln::msgs; use util::events; use util::test_utils; use util::logger::Logger; use secp256k1::Secp256k1; use secp256k1::key::{SecretKey, PublicKey}; use rand::{thread_rng, Rng}; use std::sync::{Arc}; #[derive(PartialEq, Eq, Clone, Hash)] struct FileDescriptor { fd: u16, } impl SocketDescriptor for FileDescriptor { fn send_data(&mut self, data: &Vec, write_offset: usize, _resume_read: bool) -> usize { assert!(write_offset < data.len()); data.len() - write_offset } fn disconnect_socket(&mut self) {} } fn create_network(peer_count: usize) -> Vec> { let secp_ctx = Secp256k1::new(); let mut peers = Vec::new(); let mut rng = thread_rng(); let logger : Arc = Arc::new(test_utils::TestLogger::new()); for _ in 0..peer_count { let chan_handler = test_utils::TestChannelMessageHandler::new(); let router = test_utils::TestRoutingMessageHandler::new(); let node_id = { let mut key_slice = [0;32]; rng.fill_bytes(&mut key_slice); SecretKey::from_slice(&secp_ctx, &key_slice).unwrap() }; let msg_handler = MessageHandler { chan_handler: Arc::new(chan_handler), route_handler: Arc::new(router) }; let peer = PeerManager::new(msg_handler, node_id, Arc::clone(&logger)); peers.push(peer); } peers } fn establish_connection(peer_a: &PeerManager, peer_b: &PeerManager) { let secp_ctx = Secp256k1::new(); let their_id = PublicKey::from_secret_key(&secp_ctx, &peer_b.our_node_secret); let fd = FileDescriptor { fd: 1}; peer_a.new_inbound_connection(fd.clone()).unwrap(); peer_a.peers.lock().unwrap().node_id_to_descriptor.insert(their_id, fd.clone()); } #[test] fn test_disconnect_peer() { // Simple test which builds a network of PeerManager, connects and brings them to NoiseState::Finished and // push an DisconnectPeer event to remove the node flagged by id let mut peers = create_network(2); 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); let chan_handler = test_utils::TestChannelMessageHandler::new(); chan_handler.pending_events.lock().unwrap().push(events::MessageSendEvent::HandleError { node_id: their_id, action: Some(msgs::ErrorAction::DisconnectPeer { msg: None }), }); assert_eq!(chan_handler.pending_events.lock().unwrap().len(), 1); peers[0].message_handler.chan_handler = Arc::new(chan_handler); peers[0].process_events(); assert_eq!(peers[0].peers.lock().unwrap().peers.len(), 0); } }