+//! The top-level routing/network map tracking logic lives here.
+//!
+//! You probably want to create a Router and use that as your RoutingMessageHandler and then
+//! interrogate it to get routes for your own payments.
+
use secp256k1::key::PublicKey;
use secp256k1::{Secp256k1,Message};
use secp256k1;
use bitcoin::util::hash::Sha256dHash;
+use bitcoin::blockdata::script::Builder;
+use bitcoin::blockdata::opcodes;
+use chain::chaininterface::{ChainError, ChainWatchInterface};
use ln::channelmanager;
-use ln::msgs::{ErrorAction,HandleError,RoutingMessageHandler,MsgEncodable,NetAddress,GlobalFeatures};
+use ln::msgs::{DecodeError,ErrorAction,HandleError,RoutingMessageHandler,NetAddress,GlobalFeatures};
use ln::msgs;
+use util::ser::{Writeable, Readable};
use util::logger::Logger;
use std::cmp;
/// A hop in a route
#[derive(Clone)]
pub struct RouteHop {
+ /// The node_id of the node at this hop.
pub pubkey: PublicKey,
/// The channel that should be used from the previous hop to reach this node.
pub short_channel_id: u64,
pub hops: Vec<RouteHop>,
}
+impl Writeable for Route {
+ fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+ (self.hops.len() as u8).write(writer)?;
+ for hop in self.hops.iter() {
+ hop.pubkey.write(writer)?;
+ hop.short_channel_id.write(writer)?;
+ hop.fee_msat.write(writer)?;
+ hop.cltv_expiry_delta.write(writer)?;
+ }
+ Ok(())
+ }
+}
+
+impl<R: ::std::io::Read> Readable<R> for Route {
+ fn read(reader: &mut R) -> Result<Route, DecodeError> {
+ let hops_count: u8 = Readable::read(reader)?;
+ let mut hops = Vec::with_capacity(hops_count as usize);
+ for _ in 0..hops_count {
+ hops.push(RouteHop {
+ pubkey: Readable::read(reader)?,
+ short_channel_id: Readable::read(reader)?,
+ fee_msat: Readable::read(reader)?,
+ cltv_expiry_delta: Readable::read(reader)?,
+ });
+ }
+ Ok(Route {
+ hops
+ })
+ }
+}
+
struct DirectionalChannelInfo {
src_node_id: PublicKey,
last_update: u32,
our_node_id: PublicKey,
nodes: HashMap<PublicKey, NodeInfo>,
}
-
+struct MutNetworkMap<'a> {
+ #[cfg(feature = "non_bitcoin_chain_hash_routing")]
+ channels: &'a mut HashMap<(u64, Sha256dHash), ChannelInfo>,
+ #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
+ channels: &'a mut HashMap<u64, ChannelInfo>,
+ nodes: &'a mut HashMap<PublicKey, NodeInfo>,
+}
+impl NetworkMap {
+ fn borrow_parts(&mut self) -> MutNetworkMap {
+ MutNetworkMap {
+ channels: &mut self.channels,
+ nodes: &mut self.nodes,
+ }
+ }
+}
impl std::fmt::Display for NetworkMap {
fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
write!(f, "Node id {} network map\n[Channels]\n", log_pubkey!(self.our_node_id))?;
/// A channel descriptor which provides a last-hop route to get_route
pub struct RouteHint {
+ /// The node_id of the non-target end of the route
pub src_node_id: PublicKey,
+ /// The short_channel_id of this channel
pub short_channel_id: u64,
+ /// The static msat-denominated fee which must be paid to use this channel
pub fee_base_msat: u32,
+ /// The dynamic proportional fee which must be paid to use this channel, denominated in
+ /// millionths of the value being forwarded to the next hop.
pub fee_proportional_millionths: u32,
+ /// The difference in CLTV values between this node and the next node.
pub cltv_expiry_delta: u16,
+ /// The minimum value, in msat, which must be relayed to the next hop.
pub htlc_minimum_msat: u64,
}
pub struct Router {
secp_ctx: Secp256k1<secp256k1::VerifyOnly>,
network_map: RwLock<NetworkMap>,
+ chain_monitor: Arc<ChainWatchInterface>,
logger: Arc<Logger>,
}
}
impl RoutingMessageHandler for Router {
- fn handle_node_announcement(&self, msg: &msgs::NodeAnnouncement) -> Result<(), HandleError> {
+ fn handle_node_announcement(&self, msg: &msgs::NodeAnnouncement) -> Result<bool, HandleError> {
let msg_hash = Message::from_slice(&Sha256dHash::from_data(&msg.contents.encode()[..])[..]).unwrap();
secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &msg.contents.node_id);
+ if msg.contents.features.requires_unknown_bits() {
+ panic!("Unknown-required-features NodeAnnouncements should never deserialize!");
+ }
+
let mut network = self.network_map.write().unwrap();
match network.nodes.get_mut(&msg.contents.node_id) {
None => Err(HandleError{err: "No existing channels for node_announcement", action: Some(ErrorAction::IgnoreError)}),
node.rgb = msg.contents.rgb;
node.alias = msg.contents.alias;
node.addresses = msg.contents.addresses.clone();
- Ok(())
+ Ok(msg.contents.excess_data.is_empty() && msg.contents.excess_address_data.is_empty() && !msg.contents.features.supports_unknown_bits())
}
}
}
fn handle_channel_announcement(&self, msg: &msgs::ChannelAnnouncement) -> Result<bool, HandleError> {
+ if msg.contents.node_id_1 == msg.contents.node_id_2 || msg.contents.bitcoin_key_1 == msg.contents.bitcoin_key_2 {
+ return Err(HandleError{err: "Channel announcement node had a channel with itself", action: Some(ErrorAction::IgnoreError)});
+ }
+
let msg_hash = Message::from_slice(&Sha256dHash::from_data(&msg.contents.encode()[..])[..]).unwrap();
secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_1, &msg.contents.node_id_1);
secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_2, &msg.contents.node_id_2);
secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_1, &msg.contents.bitcoin_key_1);
secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_2, &msg.contents.bitcoin_key_2);
- //TODO: Call blockchain thing to ask if the short_channel_id is valid
- //TODO: Only allow bitcoin chain_hash
-
if msg.contents.features.requires_unknown_bits() {
- return Err(HandleError{err: "Channel announcement required unknown feature flags", action: None});
+ panic!("Unknown-required-features ChannelAnnouncements should never deserialize!");
}
- let mut network = self.network_map.write().unwrap();
+ let checked_utxo = match self.chain_monitor.get_chain_utxo(msg.contents.chain_hash, msg.contents.short_channel_id) {
+ Ok((script_pubkey, _value)) => {
+ let expected_script = Builder::new().push_opcode(opcodes::All::OP_PUSHNUM_2)
+ .push_slice(&msg.contents.bitcoin_key_1.serialize())
+ .push_slice(&msg.contents.bitcoin_key_2.serialize())
+ .push_opcode(opcodes::All::OP_PUSHNUM_2).push_opcode(opcodes::All::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
+ if script_pubkey != expected_script {
+ return Err(HandleError{err: "Channel announcement keys didn't match on-chain script", action: Some(ErrorAction::IgnoreError)});
+ }
+ //TODO: Check if value is worth storing, use it to inform routing, and compare it
+ //to the new HTLC max field in channel_update
+ true
+ },
+ Err(ChainError::NotSupported) => {
+ // Tentatively accept, potentially exposing us to DoS attacks
+ false
+ },
+ Err(ChainError::NotWatched) => {
+ return Err(HandleError{err: "Channel announced on an unknown chain", action: Some(ErrorAction::IgnoreError)});
+ },
+ Err(ChainError::UnknownTx) => {
+ return Err(HandleError{err: "Channel announced without corresponding UTXO entry", action: Some(ErrorAction::IgnoreError)});
+ },
+ };
+
+ let mut network_lock = self.network_map.write().unwrap();
+ let network = network_lock.borrow_parts();
+
+ let chan_info = ChannelInfo {
+ features: msg.contents.features.clone(),
+ one_to_two: DirectionalChannelInfo {
+ src_node_id: msg.contents.node_id_1.clone(),
+ last_update: 0,
+ enabled: false,
+ cltv_expiry_delta: u16::max_value(),
+ htlc_minimum_msat: u64::max_value(),
+ fee_base_msat: u32::max_value(),
+ fee_proportional_millionths: u32::max_value(),
+ },
+ two_to_one: DirectionalChannelInfo {
+ src_node_id: msg.contents.node_id_2.clone(),
+ last_update: 0,
+ enabled: false,
+ cltv_expiry_delta: u16::max_value(),
+ htlc_minimum_msat: u64::max_value(),
+ fee_base_msat: u32::max_value(),
+ fee_proportional_millionths: u32::max_value(),
+ }
+ };
match network.channels.entry(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
- Entry::Occupied(_) => {
+ Entry::Occupied(mut entry) => {
//TODO: because asking the blockchain if short_channel_id is valid is only optional
//in the blockchain API, we need to handle it smartly here, though its unclear
//exactly how...
- return Err(HandleError{err: "Already have knowledge of channel", action: Some(ErrorAction::IgnoreError)})
+ if checked_utxo {
+ // Either our UTXO provider is busted, there was a reorg, or the UTXO provider
+ // only sometimes returns results. In any case remove the previous entry. Note
+ // that the spec expects us to "blacklist" the node_ids involved, but we can't
+ // do that because
+ // a) we don't *require* a UTXO provider that always returns results.
+ // b) we don't track UTXOs of channels we know about and remove them if they
+ // get reorg'd out.
+ // c) it's unclear how to do so without exposing ourselves to massive DoS risk.
+ Self::remove_channel_in_nodes(network.nodes, &entry.get(), msg.contents.short_channel_id);
+ *entry.get_mut() = chan_info;
+ } else {
+ return Err(HandleError{err: "Already have knowledge of channel", action: Some(ErrorAction::IgnoreError)})
+ }
},
Entry::Vacant(entry) => {
- entry.insert(ChannelInfo {
- features: msg.contents.features.clone(),
- one_to_two: DirectionalChannelInfo {
- src_node_id: msg.contents.node_id_1.clone(),
- last_update: 0,
- enabled: false,
- cltv_expiry_delta: u16::max_value(),
- htlc_minimum_msat: u64::max_value(),
- fee_base_msat: u32::max_value(),
- fee_proportional_millionths: u32::max_value(),
- },
- two_to_one: DirectionalChannelInfo {
- src_node_id: msg.contents.node_id_2.clone(),
- last_update: 0,
- enabled: false,
- cltv_expiry_delta: u16::max_value(),
- htlc_minimum_msat: u64::max_value(),
- fee_base_msat: u32::max_value(),
- fee_proportional_millionths: u32::max_value(),
- }
- });
+ entry.insert(chan_info);
}
};
add_channel_to_node!(msg.contents.node_id_1);
add_channel_to_node!(msg.contents.node_id_2);
- Ok(!msg.contents.features.supports_unknown_bits())
+ Ok(msg.contents.excess_data.is_empty() && !msg.contents.features.supports_unknown_bits())
}
fn handle_htlc_fail_channel_update(&self, update: &msgs::HTLCFailChannelUpdate) {
&msgs::HTLCFailChannelUpdate::ChannelUpdateMessage { ref msg } => {
let _ = self.handle_channel_update(msg);
},
- &msgs::HTLCFailChannelUpdate::ChannelClosed { ref short_channel_id } => {
+ &msgs::HTLCFailChannelUpdate::ChannelClosed { ref short_channel_id, ref is_permanent } => {
let mut network = self.network_map.write().unwrap();
- if let Some(chan) = network.channels.remove(short_channel_id) {
- network.nodes.get_mut(&chan.one_to_two.src_node_id).unwrap().channels.retain(|chan_id| {
- chan_id != NetworkMap::get_short_id(chan_id)
- });
- network.nodes.get_mut(&chan.two_to_one.src_node_id).unwrap().channels.retain(|chan_id| {
- chan_id != NetworkMap::get_short_id(chan_id)
- });
+ if *is_permanent {
+ if let Some(chan) = network.channels.remove(short_channel_id) {
+ Self::remove_channel_in_nodes(&mut network.nodes, &chan, *short_channel_id);
+ }
+ } else {
+ if let Some(chan) = network.channels.get_mut(short_channel_id) {
+ chan.one_to_two.enabled = false;
+ chan.two_to_one.enabled = false;
+ }
+ }
+ },
+ &msgs::HTLCFailChannelUpdate::NodeFailure { ref node_id, ref is_permanent } => {
+ if *is_permanent {
+ //TODO: Wholly remove the node
+ } else {
+ self.mark_node_bad(node_id, false);
}
},
}
}
- fn handle_channel_update(&self, msg: &msgs::ChannelUpdate) -> Result<(), HandleError> {
+ fn handle_channel_update(&self, msg: &msgs::ChannelUpdate) -> Result<bool, HandleError> {
let mut network = self.network_map.write().unwrap();
let dest_node_id;
let chan_enabled = msg.contents.flags & (1 << 1) != (1 << 1);
mut_node.lowest_inbound_channel_fee_proportional_millionths = lowest_inbound_channel_fee_proportional_millionths;
}
- Ok(())
+ Ok(msg.contents.excess_data.is_empty())
}
}
}
impl Router {
- pub fn new(our_pubkey: PublicKey, logger: Arc<Logger>) -> Router {
+ /// Creates a new router with the given node_id to be used as the source for get_route()
+ pub fn new(our_pubkey: PublicKey, chain_monitor: Arc<ChainWatchInterface>, logger: Arc<Logger>) -> Router {
let mut nodes = HashMap::new();
nodes.insert(our_pubkey.clone(), NodeInfo {
channels: Vec::new(),
our_node_id: our_pubkey,
nodes: nodes,
}),
+ chain_monitor,
logger,
}
}
unimplemented!();
}
+ fn remove_channel_in_nodes(nodes: &mut HashMap<PublicKey, NodeInfo>, chan: &ChannelInfo, short_channel_id: u64) {
+ macro_rules! remove_from_node {
+ ($node_id: expr) => {
+ if let Entry::Occupied(mut entry) = nodes.entry($node_id) {
+ entry.get_mut().channels.retain(|chan_id| {
+ short_channel_id != *NetworkMap::get_short_id(chan_id)
+ });
+ if entry.get().channels.is_empty() {
+ entry.remove_entry();
+ }
+ } else {
+ panic!("Had channel that pointed to unknown node (ie inconsistent network map)!");
+ }
+ }
+ }
+ remove_from_node!(chan.one_to_two.src_node_id);
+ remove_from_node!(chan.two_to_one.src_node_id);
+ }
+
/// Gets a route from us to the given target node.
+ ///
/// Extra routing hops between known nodes and the target will be used if they are included in
/// last_hops.
+ ///
/// If some channels aren't announced, it may be useful to fill in a first_hops with the
/// results from a local ChannelManager::list_usable_channels() call. If it is filled in, our
/// (this Router's) view of our local channels will be ignored, and only those in first_hops
- /// will be used. Panics if first_hops contains channels without short_channel_ids
+ /// will be used.
+ ///
+ /// Panics if first_hops contains channels without short_channel_ids
/// (ChannelManager::list_usable_channels will never include such channels).
+ ///
/// The fees on channels from us to next-hops are ignored (as they are assumed to all be
/// equal), however the enabled/disabled bit on such channels as well as the htlc_minimum_msat
/// *is* checked as they may change based on the receiving node.
#[cfg(test)]
mod tests {
+ use chain::chaininterface;
use ln::channelmanager;
use ln::router::{Router,NodeInfo,NetworkMap,ChannelInfo,DirectionalChannelInfo,RouteHint};
use ln::msgs::GlobalFeatures;
use util::logger::Logger;
use bitcoin::util::hash::Sha256dHash;
+ use bitcoin::network::constants::Network;
use hex;
let secp_ctx = Secp256k1::new();
let our_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap());
let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::new());
- let router = Router::new(our_id, Arc::clone(&logger));
+ let chain_monitor = Arc::new(chaininterface::ChainWatchInterfaceUtil::new(Network::Testnet, Arc::clone(&logger)));
+ let router = Router::new(our_id, chain_monitor, Arc::clone(&logger));
// Build network from our_id to node8:
//