Add ability to broadcast our own node_announcement.
[rust-lightning] / lightning / src / ln / channelmanager.rs
index 6c1f1abbb4b446d38f36a58ef6c6acb6ad8dd878..60c7a6a2bef70801fe08949c623dd18aab599dbe 100644 (file)
@@ -30,7 +30,7 @@ use chain::transaction::OutPoint;
 use ln::channel::{Channel, ChannelError};
 use ln::channelmonitor::{ChannelMonitor, ChannelMonitorUpdateErr, ManyChannelMonitor, CLTV_CLAIM_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS, ANTI_REORG_DELAY};
 use ln::router::Route;
-use ln::features::InitFeatures;
+use ln::features::{InitFeatures, NodeFeatures};
 use ln::msgs;
 use ln::onion_utils;
 use ln::msgs::{ChannelMessageHandler, DecodeError, LightningError};
@@ -38,21 +38,19 @@ use chain::keysinterface::{ChannelKeys, KeysInterface, InMemoryChannelKeys};
 use util::config::UserConfig;
 use util::{byte_utils, events};
 use util::ser::{Readable, ReadableArgs, Writeable, Writer};
-use util::chacha20::ChaCha20;
+use util::chacha20::{ChaCha20, ChaChaReader};
 use util::logger::Logger;
 use util::errors::APIError;
 
 use std::{cmp, mem};
 use std::collections::{HashMap, hash_map, HashSet};
-use std::io::Cursor;
+use std::io::{Cursor, Read};
 use std::sync::{Arc, Mutex, MutexGuard, RwLock};
 use std::sync::atomic::{AtomicUsize, Ordering};
 use std::time::Duration;
 use std::marker::{Sync, Send};
 use std::ops::Deref;
 
-const SIXTY_FIVE_ZEROS: [u8; 65] = [0; 65];
-
 // We hold various information about HTLC relay in the HTLC objects in Channel itself:
 //
 // Upon receipt of an HTLC from a peer, we'll give it a PendingHTLCStatus indicating if it should
@@ -357,6 +355,8 @@ pub struct ChannelManager<ChanSigner: ChannelKeys, M: Deref> where M::Target: Ma
        channel_state: Mutex<ChannelHolder<ChanSigner>>,
        our_network_key: SecretKey,
 
+       last_node_announcement_serial: AtomicUsize,
+
        /// The bulk of our storage will eventually be here (channels and message queues and the like).
        /// If we are connected to a peer we always at least have an entry here, even if no channels
        /// are currently open with that peer.
@@ -651,6 +651,8 @@ impl<ChanSigner: ChannelKeys, M: Deref> ChannelManager<ChanSigner, M> where M::T
                        }),
                        our_network_key: keys_manager.get_node_secret(),
 
+                       last_node_announcement_serial: AtomicUsize::new(0),
+
                        per_peer_state: RwLock::new(HashMap::new()),
 
                        pending_events: Mutex::new(Vec::new()),
@@ -906,22 +908,30 @@ impl<ChanSigner: ChannelKeys, M: Deref> ChannelManager<ChanSigner, M> where M::T
                }
 
                let mut chacha = ChaCha20::new(&rho, &[0u8; 8]);
-               let next_hop_data = {
-                       let mut decoded = [0; 65];
-                       chacha.process(&msg.onion_routing_packet.hop_data[0..65], &mut decoded);
-                       match msgs::OnionHopData::read(&mut Cursor::new(&decoded[..])) {
+               let mut chacha_stream = ChaChaReader { chacha: &mut chacha, read: Cursor::new(&msg.onion_routing_packet.hop_data[..]) };
+               let (next_hop_data, next_hop_hmac) = {
+                       match msgs::OnionHopData::read(&mut chacha_stream) {
                                Err(err) => {
                                        let error_code = match err {
                                                msgs::DecodeError::UnknownVersion => 0x4000 | 1, // unknown realm byte
+                                               msgs::DecodeError::UnknownRequiredFeature|
+                                               msgs::DecodeError::InvalidValue|
+                                               msgs::DecodeError::ShortRead => 0x4000 | 22, // invalid_onion_payload
                                                _ => 0x2000 | 2, // Should never happen
                                        };
                                        return_err!("Unable to decode our hop data", error_code, &[0;0]);
                                },
-                               Ok(msg) => msg
+                               Ok(msg) => {
+                                       let mut hmac = [0; 32];
+                                       if let Err(_) = chacha_stream.read_exact(&mut hmac[..]) {
+                                               return_err!("Unable to decode hop data", 0x4000 | 22, &[0;0]);
+                                       }
+                                       (msg, hmac)
+                               },
                        }
                };
 
-               let pending_forward_info = if next_hop_data.hmac == [0; 32] {
+               let pending_forward_info = if next_hop_hmac == [0; 32] {
                                #[cfg(test)]
                                {
                                        // In tests, make sure that the initial onion pcket data is, at least, non-0.
@@ -931,10 +941,11 @@ impl<ChanSigner: ChannelKeys, M: Deref> ChannelManager<ChanSigner, M> where M::T
                                        // as-is (and were originally 0s).
                                        // Of course reverse path calculation is still pretty easy given naive routing
                                        // algorithms, but this fixes the most-obvious case.
-                                       let mut new_packet_data = [0; 19*65];
-                                       chacha.process(&msg.onion_routing_packet.hop_data[65..], &mut new_packet_data[0..19*65]);
-                                       assert_ne!(new_packet_data[0..65], [0; 65][..]);
-                                       assert_ne!(new_packet_data[..], [0; 19*65][..]);
+                                       let mut next_bytes = [0; 32];
+                                       chacha_stream.read_exact(&mut next_bytes).unwrap();
+                                       assert_ne!(next_bytes[..], [0; 32][..]);
+                                       chacha_stream.read_exact(&mut next_bytes).unwrap();
+                                       assert_ne!(next_bytes[..], [0; 32][..]);
                                }
 
                                // OUR PAYMENT!
@@ -966,8 +977,19 @@ impl<ChanSigner: ChannelKeys, M: Deref> ChannelManager<ChanSigner, M> where M::T
                                })
                        } else {
                                let mut new_packet_data = [0; 20*65];
-                               chacha.process(&msg.onion_routing_packet.hop_data[65..], &mut new_packet_data[0..19*65]);
-                               chacha.process(&SIXTY_FIVE_ZEROS[..], &mut new_packet_data[19*65..]);
+                               let read_pos = chacha_stream.read(&mut new_packet_data).unwrap();
+                               #[cfg(debug_assertions)]
+                               {
+                                       // Check two things:
+                                       // a) that the behavior of our stream here will return Ok(0) even if the TLV
+                                       //    read above emptied out our buffer and the unwrap() wont needlessly panic
+                                       // b) that we didn't somehow magically end up with extra data.
+                                       let mut t = [0; 1];
+                                       debug_assert!(chacha_stream.read(&mut t).unwrap() == 0);
+                               }
+                               // Once we've emptied the set of bytes our peer gave us, encrypt 0 bytes until we
+                               // fill the onion hop data we'll forward to our next-hop peer.
+                               chacha_stream.chacha.process_in_place(&mut new_packet_data[read_pos..]);
 
                                let mut new_pubkey = msg.onion_routing_packet.public_key.unwrap();
 
@@ -986,13 +1008,21 @@ impl<ChanSigner: ChannelKeys, M: Deref> ChannelManager<ChanSigner, M> where M::T
                                        version: 0,
                                        public_key,
                                        hop_data: new_packet_data,
-                                       hmac: next_hop_data.hmac.clone(),
+                                       hmac: next_hop_hmac.clone(),
+                               };
+
+                               let short_channel_id = match next_hop_data.format {
+                                       msgs::OnionHopDataFormat::Legacy { short_channel_id } => short_channel_id,
+                                       msgs::OnionHopDataFormat::NonFinalNode { short_channel_id } => short_channel_id,
+                                       msgs::OnionHopDataFormat::FinalNode => {
+                                               return_err!("Final Node OnionHopData provided for us as an intermediary node", 0x4000 | 22, &[0;0]);
+                                       },
                                };
 
                                PendingHTLCStatus::Forward(PendingForwardHTLCInfo {
                                        onion_packet: Some(outgoing_packet),
                                        payment_hash: msg.payment_hash.clone(),
-                                       short_channel_id: next_hop_data.short_channel_id,
+                                       short_channel_id: short_channel_id,
                                        incoming_shared_secret: shared_secret,
                                        amt_to_forward: next_hop_data.amt_to_forward,
                                        outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
@@ -1137,6 +1167,9 @@ impl<ChanSigner: ChannelKeys, M: Deref> ChannelManager<ChanSigner, M> where M::T
                let onion_keys = secp_call!(onion_utils::construct_onion_keys(&self.secp_ctx, &route, &session_priv),
                                APIError::RouteError{err: "Pubkey along hop was maliciously selected"});
                let (onion_payloads, htlc_msat, htlc_cltv) = onion_utils::build_onion_payloads(&route, cur_height)?;
+               if onion_utils::route_size_insane(&onion_payloads) {
+                       return Err(APIError::RouteError{err: "Route had too large size once"});
+               }
                let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, prng_seed, &payment_hash);
 
                let _ = self.total_consistency_lock.read().unwrap();
@@ -1285,6 +1318,37 @@ impl<ChanSigner: ChannelKeys, M: Deref> ChannelManager<ChanSigner, M> where M::T
                })
        }
 
+       /// Generates a signed node_announcement from the given arguments and creates a
+       /// BroadcastNodeAnnouncement event.
+       ///
+       /// RGB is a node "color" and alias a printable human-readable string to describe this node to
+       /// humans. They carry no in-protocol meaning.
+       ///
+       /// addresses represent the set (possibly empty) of socket addresses on which this node accepts
+       /// incoming connections.
+       pub fn broadcast_node_announcement(&self, rgb: [u8; 3], alias: [u8; 32], addresses: msgs::NetAddressSet) {
+               let _ = self.total_consistency_lock.read().unwrap();
+
+               let announcement = msgs::UnsignedNodeAnnouncement {
+                       features: NodeFeatures::supported(),
+                       timestamp: self.last_node_announcement_serial.fetch_add(1, Ordering::AcqRel) as u32,
+                       node_id: self.get_our_node_id(),
+                       rgb, alias,
+                       addresses: addresses.to_vec(),
+                       excess_address_data: Vec::new(),
+                       excess_data: Vec::new(),
+               };
+               let msghash = hash_to_message!(&Sha256dHash::hash(&announcement.encode()[..])[..]);
+
+               let mut channel_state = self.channel_state.lock().unwrap();
+               channel_state.pending_msg_events.push(events::MessageSendEvent::BroadcastNodeAnnouncement {
+                       msg: msgs::NodeAnnouncement {
+                               signature: self.secp_ctx.sign(&msghash, &self.our_network_key),
+                               contents: announcement
+                       },
+               });
+       }
+
        /// Processes HTLCs which are pending waiting on random forward delay.
        ///
        /// Should only really ever be called in response to a PendingHTLCsForwardable event.
@@ -2880,6 +2944,7 @@ impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send> ChannelMessageHandler for
                                        &events::MessageSendEvent::SendShutdown { ref node_id, .. } => node_id != their_node_id,
                                        &events::MessageSendEvent::SendChannelReestablish { ref node_id, .. } => node_id != their_node_id,
                                        &events::MessageSendEvent::BroadcastChannelAnnouncement { .. } => true,
+                                       &events::MessageSendEvent::BroadcastNodeAnnouncement { .. } => true,
                                        &events::MessageSendEvent::BroadcastChannelUpdate { .. } => true,
                                        &events::MessageSendEvent::HandleError { ref node_id, .. } => node_id != their_node_id,
                                        &events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => true,
@@ -3193,6 +3258,8 @@ impl<ChanSigner: ChannelKeys + Writeable, M: Deref> Writeable for ChannelManager
                        peer_state.latest_features.write(writer)?;
                }
 
+               (self.last_node_announcement_serial.load(Ordering::Acquire) as u32).write(writer)?;
+
                Ok(())
        }
 }
@@ -3336,6 +3403,8 @@ impl<'a, R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>, M: Deref> R
                        per_peer_state.insert(peer_pubkey, Mutex::new(peer_state));
                }
 
+               let last_node_announcement_serial: u32 = Readable::read(reader)?;
+
                let channel_manager = ChannelManager {
                        genesis_hash,
                        fee_estimator: args.fee_estimator,
@@ -3355,6 +3424,8 @@ impl<'a, R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>, M: Deref> R
                        }),
                        our_network_key: args.keys_manager.get_node_secret(),
 
+                       last_node_announcement_serial: AtomicUsize::new(last_node_announcement_serial as usize),
+
                        per_peer_state: RwLock::new(per_peer_state),
 
                        pending_events: Mutex::new(Vec::new()),