[rust-lightning] / src / ln / channelmanager.rs

use bitcoin::blockdata::block::BlockHeader;
use bitcoin::blockdata::transaction::Transaction;
use bitcoin::blockdata::constants::genesis_block;
use bitcoin::network::constants::Network;
use bitcoin::network::serialize::BitcoinHash;
use bitcoin::util::hash::Sha256dHash;
use bitcoin::util::uint::Uint256;

use secp256k1::key::{SecretKey,PublicKey};
use secp256k1::{Secp256k1,Message};
use secp256k1::ecdh::SharedSecret;
use secp256k1;

use chain::chaininterface::{BroadcasterInterface,ChainListener,ChainWatchInterface,FeeEstimator};
use ln::channel::Channel;
use ln::channelmonitor::ManyChannelMonitor;
use ln::router::Route;
use ln::msgs;
use ln::msgs::{HandleError,ChannelMessageHandler,MsgEncodable,MsgDecodable};
use util::{byte_utils, events, internal_traits, rng};
use util::sha2::Sha256;

use crypto::mac::{Mac,MacResult};
use crypto::hmac::Hmac;
use crypto::digest::Digest;
use crypto::symmetriccipher::SynchronousStreamCipher;
use crypto::chacha20::ChaCha20;

use std::sync::{Mutex,MutexGuard,Arc};
use std::collections::HashMap;
use std::collections::hash_map;
use std::{ptr, mem};
use std::time::{Instant,Duration};

/// Stores the info we will need to send when we want to forward an HTLC onwards
pub struct PendingForwardHTLCInfo {
        onion_packet: Option<msgs::OnionPacket>,
        payment_hash: [u8; 32],
        short_channel_id: u64,
        prev_short_channel_id: u64,
        amt_to_forward: u64,
        outgoing_cltv_value: u32,
}

#[cfg(feature = "fuzztarget")]
impl PendingForwardHTLCInfo {
        pub fn dummy() -> Self {
                Self {
                        onion_packet: None,
                        payment_hash: [0; 32],
                        short_channel_id: 0,
                        prev_short_channel_id: 0,
                        amt_to_forward: 0,
                        outgoing_cltv_value: 0,
                }
        }
}

enum PendingOutboundHTLC {
        IntermediaryHopData {
                source_short_channel_id: u64,
                incoming_packet_shared_secret: SharedSecret,
        },
        OutboundRoute {
                route: Route,
        },
        /// Used for channel rebalancing
        CycledRoute {
                source_short_channel_id: u64,
                incoming_packet_shared_secret: SharedSecret,
                route: Route,
        }
}

enum HTLCFailReason<'a> {
        ErrorPacket {
                err: &'a msgs::OnionErrorPacket,
        },
        Reason {
                failure_code: u16,
                data: &'a[u8],
        }
}

/// We hold back HTLCs we intend to relay for a random interval in the range (this, 5*this). This
/// provides some limited amount of privacy. Ideally this would range from somewhere like 1 second
/// to 30 seconds, but people expect lightning to be, you know, kinda fast, sadly. We could
/// probably increase this significantly.
const MIN_HTLC_RELAY_HOLDING_CELL_MILLIS: u32 = 50;

struct ChannelHolder {
        by_id: HashMap<Uint256, Channel>,
        short_to_id: HashMap<u64, Uint256>,
        next_forward: Instant,
        /// short channel id -> forward infos. Key of 0 means payments received
        forward_htlcs: HashMap<u64, Vec<PendingForwardHTLCInfo>>,
        claimable_htlcs: HashMap<[u8; 32], PendingOutboundHTLC>,
}
struct MutChannelHolder<'a> {
        by_id: &'a mut HashMap<Uint256, Channel>,
        short_to_id: &'a mut HashMap<u64, Uint256>,
        next_forward: &'a mut Instant,
        /// short channel id -> forward infos. Key of 0 means payments received
        forward_htlcs: &'a mut HashMap<u64, Vec<PendingForwardHTLCInfo>>,
        claimable_htlcs: &'a mut HashMap<[u8; 32], PendingOutboundHTLC>,
}
impl ChannelHolder {
        fn borrow_parts(&mut self) -> MutChannelHolder {
                MutChannelHolder {
                        by_id: &mut self.by_id,
                        short_to_id: &mut self.short_to_id,
                        next_forward: &mut self.next_forward,
                        /// short channel id -> forward infos. Key of 0 means payments received
                        forward_htlcs: &mut self.forward_htlcs,
                        claimable_htlcs: &mut self.claimable_htlcs,
                }
        }
}

/// Manager which keeps track of a number of channels and sends messages to the appropriate
/// channel, also tracking HTLC preimages and forwarding onion packets appropriately.
/// Implements ChannelMessageHandler, handling the multi-channel parts and passing things through
/// to individual Channels.
pub struct ChannelManager {
        genesis_hash: Sha256dHash,
        fee_estimator: Arc<FeeEstimator>,
        monitor: Arc<ManyChannelMonitor>,
        chain_monitor: Arc<ChainWatchInterface>,
        tx_broadcaster: Arc<BroadcasterInterface>,

        announce_channels_publicly: bool,
        fee_proportional_millionths: u32,
        secp_ctx: Secp256k1,

        channel_state: Mutex<ChannelHolder>,
        our_network_key: SecretKey,

        pending_events: Mutex<Vec<events::Event>>,
}

const CLTV_EXPIRY_DELTA: u16 = 6 * 24 * 2; //TODO?

macro_rules! secp_call {
        ( $res : expr ) => {
                match $res {
                        Ok(key) => key,
                        //TODO: Make the err a parameter!
                        Err(_) => return Err(HandleError{err: "Key error", msg: None})
                }
        };
}

struct OnionKeys {
        #[cfg(test)]
        shared_secret: SharedSecret,
        #[cfg(test)]
        blinding_factor: [u8; 32],
        ephemeral_pubkey: PublicKey,
        rho: [u8; 32],
        mu: [u8; 32],
}

pub struct ChannelDetails {
        /// The channel's ID (prior to funding transaction generation, this is a random 32 bytes,
        /// thereafter this is the txid of the funding transaction xor the funding transaction output).
        /// Note that this means this value is *not* persistent - it can change once during the
        /// lifetime of the channel.
        pub channel_id: Uint256,
        /// The position of the funding transaction in the chain. None if the funding transaction has
        /// not yet been confirmed and the channel fully opened.
        pub short_channel_id: Option<u64>,
        pub remote_network_id: PublicKey,
        pub channel_value_satoshis: u64,
        /// The user_id passed in to create_channel, or 0 if the channel was inbound.
        pub user_id: u64,
}

impl ChannelManager {
        /// Constructs a new ChannelManager to hold several channels and route between them. This is
        /// the main "logic hub" for all channel-related actions, and implements ChannelMessageHandler.
        /// fee_proportional_millionths is an optional fee to charge any payments routed through us.
        /// Non-proportional fees are fixed according to our risk using the provided fee estimator.
        /// panics if channel_value_satoshis is >= (1 << 24)!
        pub fn new(our_network_key: SecretKey, fee_proportional_millionths: u32, announce_channels_publicly: bool, network: Network, feeest: Arc<FeeEstimator>, monitor: Arc<ManyChannelMonitor>, chain_monitor: Arc<ChainWatchInterface>, tx_broadcaster: Arc<BroadcasterInterface>) -> Result<Arc<ChannelManager>, secp256k1::Error> {
                let secp_ctx = Secp256k1::new();

                let res = Arc::new(ChannelManager {
                        genesis_hash: genesis_block(network).header.bitcoin_hash(),
                        fee_estimator: feeest.clone(),
                        monitor: monitor.clone(),
                        chain_monitor,
                        tx_broadcaster,

                        announce_channels_publicly,
                        fee_proportional_millionths,
                        secp_ctx,

                        channel_state: Mutex::new(ChannelHolder{
                                by_id: HashMap::new(),
                                short_to_id: HashMap::new(),
                                next_forward: Instant::now(),
                                forward_htlcs: HashMap::new(),
                                claimable_htlcs: HashMap::new(),
                        }),
                        our_network_key,

                        pending_events: Mutex::new(Vec::new()),
                });
                let weak_res = Arc::downgrade(&res);
                res.chain_monitor.register_listener(weak_res);
                Ok(res)
        }

        pub fn create_channel(&self, their_network_key: PublicKey, channel_value_satoshis: u64, user_id: u64) -> Result<msgs::OpenChannel, HandleError> {
                let channel = Channel::new_outbound(&*self.fee_estimator, their_network_key, channel_value_satoshis, self.announce_channels_publicly, user_id);
                let res = channel.get_open_channel(self.genesis_hash.clone(), &*self.fee_estimator)?;
                let mut channel_state = self.channel_state.lock().unwrap();
                match channel_state.by_id.insert(channel.channel_id(), channel) {
                        Some(_) => panic!("RNG is bad???"),
                        None => Ok(res)
                }
        }

        /// Gets the list of open channels, in random order. See ChannelDetail field documentation for
        /// more information.
        pub fn list_channels(&self) -> Vec<ChannelDetails> {
                let channel_state = self.channel_state.lock().unwrap();
                let mut res = Vec::with_capacity(channel_state.by_id.len());
                for (channel_id, channel) in channel_state.by_id.iter() {
                        res.push(ChannelDetails {
                                channel_id: (*channel_id).clone(),
                                short_channel_id: channel.get_short_channel_id(),
                                remote_network_id: channel.get_their_node_id(),
                                channel_value_satoshis: channel.get_value_satoshis(),
                                user_id: channel.get_user_id(),
                        });
                }
                res
        }

        /// Begins the process of closing a channel. After this call (plus some timeout), no new HTLCs
        /// will be accepted on the given channel, and after additional timeout/the closing of all
        /// pending HTLCs, the channel will be closed on chain.
        pub fn close_channel(&self, channel_id: &Uint256) -> Result<msgs::Shutdown, HandleError> {
                let res = {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        match channel_state.by_id.entry(channel_id.clone()) {
                                hash_map::Entry::Occupied(mut chan_entry) => {
                                        let res = chan_entry.get_mut().get_shutdown()?;
                                        if chan_entry.get().is_shutdown() {
                                                chan_entry.remove_entry();
                                        }
                                        res
                                },
                                hash_map::Entry::Vacant(_) => return Err(HandleError{err: "No such channel", msg: None})
                        }
                };
                for payment_hash in res.1 {
                        // unknown_next_peer...I dunno who that is anymore....
                        self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), &payment_hash, HTLCFailReason::Reason { failure_code: 0x4000 | 10, data: &[0; 0] });
                }
                Ok(res.0)
        }

        #[inline]
        fn gen_rho_mu_from_shared_secret(shared_secret: &SharedSecret) -> ([u8; 32], [u8; 32]) {
                ({
                        let mut hmac = Hmac::new(Sha256::new(), &[0x72, 0x68, 0x6f]); // rho
                        hmac.input(&shared_secret[..]);
                        let mut res = [0; 32];
                        hmac.raw_result(&mut res);
                        res
                },
                {
                        let mut hmac = Hmac::new(Sha256::new(), &[0x6d, 0x75]); // mu
                        hmac.input(&shared_secret[..]);
                        let mut res = [0; 32];
                        hmac.raw_result(&mut res);
                        res
                })
        }

        #[inline]
        fn gen_um_from_shared_secret(shared_secret: &SharedSecret) -> [u8; 32] {
                let mut hmac = Hmac::new(Sha256::new(), &[0x75, 0x6d]); // um
                hmac.input(&shared_secret[..]);
                let mut res = [0; 32];
                hmac.raw_result(&mut res);
                res
        }

        fn gen_ammag_from_shared_secret(shared_secret: &SharedSecret) -> [u8; 32] {
                let mut hmac = Hmac::new(Sha256::new(), &[0x61, 0x6d, 0x6d, 0x61, 0x67]); // ammag
                hmac.input(&shared_secret[..]);
                let mut res = [0; 32];
                hmac.raw_result(&mut res);
                res
        }

        fn construct_onion_keys(secp_ctx: &Secp256k1, route: &Route, session_priv: &SecretKey) -> Result<Vec<OnionKeys>, HandleError> {
                let mut res = Vec::with_capacity(route.hops.len());
                let mut blinded_priv = session_priv.clone();
                let mut blinded_pub = secp_call!(PublicKey::from_secret_key(secp_ctx, &blinded_priv));
                let mut first_iteration = true;

                for hop in route.hops.iter() {
                        let shared_secret = SharedSecret::new(secp_ctx, &hop.pubkey, &blinded_priv);

                        let mut sha = Sha256::new();
                        sha.input(&blinded_pub.serialize()[..]);
                        sha.input(&shared_secret[..]);
                        let mut blinding_factor = [0u8; 32];
                        sha.result(&mut blinding_factor);

                        if first_iteration {
                                blinded_pub = secp_call!(PublicKey::from_secret_key(secp_ctx, &blinded_priv));
                                first_iteration = false;
                        }
                        let ephemeral_pubkey = blinded_pub;

                        secp_call!(blinded_priv.mul_assign(secp_ctx, &secp_call!(SecretKey::from_slice(secp_ctx, &blinding_factor))));
                        blinded_pub = secp_call!(PublicKey::from_secret_key(secp_ctx, &blinded_priv));

                        let (rho, mu) = ChannelManager::gen_rho_mu_from_shared_secret(&shared_secret);

                        res.push(OnionKeys {
                                #[cfg(test)]
                                shared_secret: shared_secret,
                                #[cfg(test)]
                                blinding_factor: blinding_factor,
                                ephemeral_pubkey: ephemeral_pubkey,
                                rho: rho,
                                mu: mu,
                        });
                }

                Ok(res)
        }

        /// returns the hop data, as well as the first-hop value_msat and CLTV value we should send.
        fn build_onion_payloads(route: &Route) -> Result<(Vec<msgs::OnionHopData>, u64, u32), HandleError> {
                let mut cur_value_msat = 0u64;
                let mut cur_cltv = 0u32;
                let mut last_short_channel_id = 0;
                let mut res: Vec<msgs::OnionHopData> = Vec::with_capacity(route.hops.len());
                internal_traits::test_no_dealloc::<msgs::OnionHopData>(None);
                unsafe { res.set_len(route.hops.len()); }

                for (idx, hop) in route.hops.iter().enumerate().rev() {
                        // First hop gets special values so that it can check, on receipt, that everything is
                        // exactly as it should be (and the next hop isn't trying to probe to find out if we're
                        // the intended recipient).
                        let value_msat = if cur_value_msat == 0 { hop.fee_msat } else { cur_value_msat };
                        let cltv = if cur_cltv == 0 { hop.cltv_expiry_delta } else { cur_cltv };
                        res[idx] = msgs::OnionHopData {
                                realm: 0,
                                data: msgs::OnionRealm0HopData {
                                        short_channel_id: last_short_channel_id,
                                        amt_to_forward: value_msat,
                                        outgoing_cltv_value: cltv,
                                },
                                hmac: [0; 32],
                        };
                        cur_value_msat += hop.fee_msat;
                        if cur_value_msat >= 21000000 * 100000000 * 1000 {
                                return Err(HandleError{err: "Channel fees overflowed?!", msg: None});
                        }
                        cur_cltv += hop.cltv_expiry_delta as u32;
                        if cur_cltv >= 500000000 {
                                return Err(HandleError{err: "Channel CLTV overflowed?!", msg: None});
                        }
                        last_short_channel_id = hop.short_channel_id;
                }
                Ok((res, cur_value_msat, cur_cltv))
        }

        #[inline]
        fn shift_arr_right(arr: &mut [u8; 20*65]) {
                unsafe {
                        ptr::copy(arr[0..].as_ptr(), arr[65..].as_mut_ptr(), 19*65);
                }
                for i in 0..65 {
                        arr[i] = 0;
                }
        }

        #[inline]
        fn xor_bufs(dst: &mut[u8], src: &[u8]) {
                assert_eq!(dst.len(), src.len());

                for i in 0..dst.len() {
                        dst[i] ^= src[i];
                }
        }

        const ZERO:[u8; 21*65] = [0; 21*65];
        fn construct_onion_packet(mut payloads: Vec<msgs::OnionHopData>, onion_keys: Vec<OnionKeys>, associated_data: Vec<u8>) -> Result<msgs::OnionPacket, HandleError> {
                let mut buf = Vec::with_capacity(21*65);
                buf.resize(21*65, 0);

                let filler = {
                        let iters = payloads.len() - 1;
                        let end_len = iters * 65;
                        let mut res = Vec::with_capacity(end_len);
                        res.resize(end_len, 0);

                        for (i, keys) in onion_keys.iter().enumerate() {
                                if i == payloads.len() - 1 { continue; }
                                let mut chacha = ChaCha20::new(&keys.rho, &[0u8; 8]);
                                chacha.process(&ChannelManager::ZERO, &mut buf); // We don't have a seek function :(
                                ChannelManager::xor_bufs(&mut res[0..(i + 1)*65], &buf[(20 - i)*65..21*65]);
                        }
                        res
                };

                let mut packet_data = [0; 20*65];
                let mut hmac_res = [0; 32];

                for (i, (payload, keys)) in payloads.iter_mut().zip(onion_keys.iter()).rev().enumerate() {
                        ChannelManager::shift_arr_right(&mut packet_data);
                        payload.hmac = hmac_res;
                        packet_data[0..65].copy_from_slice(&payload.encode()[..]);

                        let mut chacha = ChaCha20::new(&keys.rho, &[0u8; 8]);
                        chacha.process(&packet_data, &mut buf[0..20*65]);
                        packet_data[..].copy_from_slice(&buf[0..20*65]);

                        if i == 0 {
                                packet_data[20*65 - filler.len()..20*65].copy_from_slice(&filler[..]);
                        }

                        let mut hmac = Hmac::new(Sha256::new(), &keys.mu);
                        hmac.input(&packet_data);
                        hmac.input(&associated_data[..]);
                        hmac.raw_result(&mut hmac_res);
                }

                Ok(msgs::OnionPacket{
                        version: 0,
                        public_key: onion_keys.first().unwrap().ephemeral_pubkey,
                        hop_data: packet_data,
                        hmac: hmac_res,
                })
        }

        /// Encrypts a failure packet. raw_packet can either be a
        /// msgs::DecodedOnionErrorPacket.encode() result or a msgs::OnionErrorPacket.data element.
        fn encrypt_failure_packet(shared_secret: &SharedSecret, raw_packet: &[u8]) -> msgs::OnionErrorPacket {
                let ammag = ChannelManager::gen_ammag_from_shared_secret(&shared_secret);

                let mut packet_crypted = Vec::with_capacity(raw_packet.len());
                packet_crypted.resize(raw_packet.len(), 0);
                let mut chacha = ChaCha20::new(&ammag, &[0u8; 8]);
                chacha.process(&raw_packet, &mut packet_crypted[..]);
                msgs::OnionErrorPacket {
                        data: packet_crypted,
                }
        }

        fn build_failure_packet(shared_secret: &SharedSecret, failure_type: u16, failure_data: &[u8]) -> msgs::DecodedOnionErrorPacket {
                assert!(failure_data.len() <= 256 - 2);

                let um = ChannelManager::gen_um_from_shared_secret(&shared_secret);

                let failuremsg = {
                        let mut res = Vec::with_capacity(2 + failure_data.len());
                        res.push(((failure_type >> 8) & 0xff) as u8);
                        res.push(((failure_type >> 0) & 0xff) as u8);
                        res.extend_from_slice(&failure_data[..]);
                        res
                };
                let pad = {
                        let mut res = Vec::with_capacity(256 - 2 - failure_data.len());
                        res.resize(256 - 2 - failure_data.len(), 0);
                        res
                };
                let mut packet = msgs::DecodedOnionErrorPacket {
                        hmac: [0; 32],
                        failuremsg: failuremsg,
                        pad: pad,
                };

                let mut hmac = Hmac::new(Sha256::new(), &um);
                hmac.input(&packet.encode()[32..]);
                hmac.raw_result(&mut packet.hmac);

                packet
        }

        fn build_first_hop_failure_packet(shared_secret: &SharedSecret, failure_type: u16, failure_data: &[u8]) -> msgs::OnionErrorPacket {
                let failure_packet = ChannelManager::build_failure_packet(shared_secret, failure_type, failure_data);
                ChannelManager::encrypt_failure_packet(shared_secret, &failure_packet.encode()[..])
        }

        /// only fails if the channel does not yet have an assigned short_id
        fn get_channel_update(&self, chan: &mut Channel) -> Result<msgs::ChannelUpdate, HandleError> {
                let short_channel_id = match chan.get_short_channel_id() {
                        None => return Err(HandleError{err: "Channel not yet established", msg: None}),
                        Some(id) => id,
                };

                let were_node_one = PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).unwrap().serialize()[..] < chan.get_their_node_id().serialize()[..];

                let unsigned = msgs::UnsignedChannelUpdate {
                        chain_hash: self.genesis_hash,
                        short_channel_id: short_channel_id,
                        timestamp: chan.get_channel_update_count(),
                        flags: (!were_node_one) as u16 | ((!chan.is_live() as u16) << 1),
                        cltv_expiry_delta: CLTV_EXPIRY_DELTA,
                        htlc_minimum_msat: chan.get_our_htlc_minimum_msat(),
                        fee_base_msat: chan.get_our_fee_base_msat(&*self.fee_estimator),
                        fee_proportional_millionths: self.fee_proportional_millionths,
                };

                let msg_hash = Sha256dHash::from_data(&unsigned.encode()[..]);
                let sig = self.secp_ctx.sign(&Message::from_slice(&msg_hash[..]).unwrap(), &self.our_network_key).unwrap(); //TODO Can we unwrap here?

                Ok(msgs::ChannelUpdate {
                        signature: sig,
                        contents: unsigned
                })
        }

        /// Sends a payment along a given route, returning the UpdateAddHTLC message to give to the
        /// first hop in route. Value parameters are provided via the last hop in route, see
        /// documentation for RouteHop fields for more info.
        /// See-also docs on Channel::send_htlc_and_commit.
        pub fn send_payment(&self, route: Route, payment_hash: [u8; 32]) -> Result<Option<(msgs::UpdateAddHTLC, msgs::CommitmentSigned)>, HandleError> {
                if route.hops.len() < 1 || route.hops.len() > 20 {
                        return Err(HandleError{err: "Route didn't go anywhere/had bogus size", msg: None});
                }
                let our_node_id = self.get_our_node_id();
                for (idx, hop) in route.hops.iter().enumerate() {
                        if idx != route.hops.len() - 1 && hop.pubkey == our_node_id {
                                return Err(HandleError{err: "Route went through us but wasn't a simple rebalance loop to us", msg: None});
                        }
                }

                let session_priv = secp_call!(SecretKey::from_slice(&self.secp_ctx, &{
                        let mut session_key = [0; 32];
                        rng::fill_bytes(&mut session_key);
                        session_key
                }));

                let associated_data = Vec::new(); //TODO: What to put here?

                let onion_keys = ChannelManager::construct_onion_keys(&self.secp_ctx, &route, &session_priv)?;
                let (onion_payloads, htlc_msat, htlc_cltv) = ChannelManager::build_onion_payloads(&route)?;
                let onion_packet = ChannelManager::construct_onion_packet(onion_payloads, onion_keys, associated_data)?;

                let mut channel_state = self.channel_state.lock().unwrap();
                let id = match channel_state.short_to_id.get(&route.hops.first().unwrap().short_channel_id) {
                        None => return Err(HandleError{err: "No channel available with first hop!", msg: None}),
                        Some(id) => id.clone()
                };
                let res = {
                        let chan = channel_state.by_id.get_mut(&id).unwrap();
                        if chan.get_their_node_id() != route.hops.first().unwrap().pubkey {
                                return Err(HandleError{err: "Node ID mismatch on first hop!", msg: None});
                        }
                        chan.send_htlc_and_commit(htlc_msat, payment_hash.clone(), htlc_cltv, onion_packet)?
                };

                if channel_state.claimable_htlcs.insert(payment_hash, PendingOutboundHTLC::OutboundRoute {
                        route: route,
                }).is_some() {
                        // TODO: We need to track these better, we're not generating these, so a
                        // third-party might make this happen:
                        panic!("payment_hash was repeated! Don't let this happen");
                }

                Ok(res)
        }

        /// Call this upon creation of a funding transaction for the given channel.
        /// Panics if a funding transaction has already been provided for this channel.
        pub fn funding_transaction_generated(&self, temporary_channel_id: &Uint256, funding_txo: (Sha256dHash, u16)) {
                let (chan, msg) = {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        match channel_state.by_id.remove(&temporary_channel_id) {
                                Some(mut chan) => {
                                        match chan.get_outbound_funding_created(funding_txo.0, funding_txo.1) {
                                                Ok(funding_msg) => {
                                                        (chan, funding_msg)
                                                },
                                                Err(_e) => {
                                                        //TODO: Push e to pendingevents
                                                        return;
                                                }
                                        }
                                },
                                None => return
                        }
                }; // Release channel lock for install_watch_outpoint call,
                let chan_monitor = chan.channel_monitor();
                match self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor) {
                        Ok(()) => {},
                        Err(_e) => {
                                //TODO: Push e to pendingevents?
                                return;
                        }
                };

                {
                        let mut pending_events = self.pending_events.lock().unwrap();
                        pending_events.push(events::Event::SendFundingCreated {
                                node_id: chan.get_their_node_id(),
                                msg: msg,
                        });
                }

                let mut channel_state = self.channel_state.lock().unwrap();
                channel_state.by_id.insert(chan.channel_id(), chan);
        }

        fn get_announcement_sigs(&self, chan: &Channel) -> Result<Option<msgs::AnnouncementSignatures>, HandleError> {
                if !chan.is_usable() { return Ok(None) }

                let (announcement, our_bitcoin_sig) = chan.get_channel_announcement(self.get_our_node_id(), self.genesis_hash.clone())?;
                let msghash = Message::from_slice(&Sha256dHash::from_data(&announcement.encode()[..])[..]).unwrap();
                let our_node_sig = secp_call!(self.secp_ctx.sign(&msghash, &self.our_network_key));

                Ok(Some(msgs::AnnouncementSignatures {
                        channel_id: chan.channel_id(),
                        short_channel_id: chan.get_short_channel_id().unwrap(),
                        node_signature: our_node_sig,
                        bitcoin_signature: our_bitcoin_sig,
                }))
        }

        pub fn process_pending_htlc_forward(&self) {
                let mut new_events = Vec::new();
                let mut failed_forwards = Vec::new();
                {
                        let mut channel_state_lock = self.channel_state.lock().unwrap();
                        let channel_state = channel_state_lock.borrow_parts();

                        if cfg!(not(feature = "fuzztarget")) && Instant::now() < *channel_state.next_forward {
                                return;
                        }

                        for (short_chan_id, pending_forwards) in channel_state.forward_htlcs.drain() {
                                if short_chan_id != 0 {
                                        let forward_chan_id = match channel_state.short_to_id.get(&short_chan_id) {
                                                Some(chan_id) => chan_id.clone(),
                                                None => {
                                                        failed_forwards.reserve(pending_forwards.len());
                                                        for forward_info in pending_forwards {
                                                                failed_forwards.push((forward_info.payment_hash, 0x4000 | 10, None));
                                                        }
                                                        // TODO: Send a failure packet back on each pending_forward
                                                        continue;
                                                }
                                        };
                                        let forward_chan = &mut channel_state.by_id.get_mut(&forward_chan_id).unwrap();

                                        let mut add_htlc_msgs = Vec::new();
                                        for forward_info in pending_forwards {
                                                match forward_chan.send_htlc(forward_info.amt_to_forward, forward_info.payment_hash, forward_info.outgoing_cltv_value, forward_info.onion_packet.unwrap()) {
                                                        Err(_e) => {
                                                                let chan_update = self.get_channel_update(forward_chan).unwrap();
                                                                failed_forwards.push((forward_info.payment_hash, 0x4000 | 7, Some(chan_update)));
                                                                continue;
                                                        },
                                                        Ok(update_add) => {
                                                                match update_add {
                                                                        Some(msg) => { add_htlc_msgs.push(msg); },
                                                                        None => {
                                                                                // Nothing to do here...we're waiting on a remote
                                                                                // revoke_and_ack before we can add anymore HTLCs. The Channel
                                                                                // will automatically handle building the update_add_htlc and
                                                                                // commitment_signed messages when we can.
                                                                                // TODO: Do some kind of timer to set the channel as !is_live()
                                                                                // as we don't really want others relying on us relaying through
                                                                                // this channel currently :/.
                                                                        }
                                                                }
                                                        }
                                                }
                                        }

                                        if !add_htlc_msgs.is_empty() {
                                                let commitment_msg = match forward_chan.send_commitment() {
                                                        Ok(msg) => msg,
                                                        Err(_) => {
                                                                //TODO: Handle...this is bad!
                                                                continue;
                                                        },
                                                };
                                                new_events.push(events::Event::SendHTLCs {
                                                        node_id: forward_chan.get_their_node_id(),
                                                        msgs: add_htlc_msgs,
                                                        commitment_msg: commitment_msg,
                                                });
                                        }
                                } else {
                                        for forward_info in pending_forwards {
                                                new_events.push(events::Event::PaymentReceived {
                                                        payment_hash: forward_info.payment_hash,
                                                        amt: forward_info.amt_to_forward,
                                                });
                                        }
                                }
                        }
                }

                for failed_forward in failed_forwards.drain(..) {
                        match failed_forward.2 {
                                None => self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), &failed_forward.0, HTLCFailReason::Reason { failure_code: failed_forward.1, data: &[0;0] }),
                                Some(chan_update) => self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), &failed_forward.0, HTLCFailReason::Reason { failure_code: failed_forward.1, data: &chan_update.encode()[..] }),
                        };
                }

                if new_events.is_empty() { return }

                let mut events = self.pending_events.lock().unwrap();
                events.reserve(new_events.len());
                for event in new_events.drain(..) {
                        events.push(event);
                }
        }

        /// Indicates that the preimage for payment_hash is unknown after a PaymentReceived event.
        pub fn fail_htlc_backwards(&self, payment_hash: &[u8; 32]) -> bool {
                self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), payment_hash, HTLCFailReason::Reason { failure_code: 0x4000 | 15, data: &[0;0] })
        }

        fn fail_htlc_backwards_internal(&self, mut channel_state: MutexGuard<ChannelHolder>, payment_hash: &[u8; 32], onion_error: HTLCFailReason) -> bool {
                let mut pending_htlc = {
                        match channel_state.claimable_htlcs.remove(payment_hash) {
                                Some(pending_htlc) => pending_htlc,
                                None => return false,
                        }
                };

                match pending_htlc {
                        PendingOutboundHTLC::CycledRoute { source_short_channel_id, incoming_packet_shared_secret, .. } => {
                                pending_htlc = PendingOutboundHTLC::IntermediaryHopData { source_short_channel_id, incoming_packet_shared_secret };
                        },
                        _ => {}
                }

                match pending_htlc {
                        PendingOutboundHTLC::CycledRoute { .. } => { panic!("WAT"); },
                        PendingOutboundHTLC::OutboundRoute { .. } => {
                                //TODO: DECRYPT route from OutboundRoute
                                mem::drop(channel_state);
                                let mut pending_events = self.pending_events.lock().unwrap();
                                pending_events.push(events::Event::PaymentFailed {
                                        payment_hash: payment_hash.clone()
                                });
                                false
                        },
                        PendingOutboundHTLC::IntermediaryHopData { source_short_channel_id, incoming_packet_shared_secret } => {
                                let err_packet = match onion_error {
                                        HTLCFailReason::Reason { failure_code, data } => {
                                                let packet = ChannelManager::build_failure_packet(&incoming_packet_shared_secret, failure_code, data).encode();
                                                ChannelManager::encrypt_failure_packet(&incoming_packet_shared_secret, &packet)
                                        },
                                        HTLCFailReason::ErrorPacket { err } => {
                                                ChannelManager::encrypt_failure_packet(&incoming_packet_shared_secret, &err.data)
                                        }
                                };

                                let (node_id, fail_msg) = {
                                        let chan_id = match channel_state.short_to_id.get(&source_short_channel_id) {
                                                Some(chan_id) => chan_id.clone(),
                                                None => return false
                                        };

                                        let chan = channel_state.by_id.get_mut(&chan_id).unwrap();
                                        match chan.get_update_fail_htlc(payment_hash, err_packet) {
                                                Ok(msg) => (chan.get_their_node_id(), msg),
                                                Err(_e) => {
                                                        //TODO: Do something with e?
                                                        return false;
                                                },
                                        }
                                };

                                mem::drop(channel_state);
                                let mut pending_events = self.pending_events.lock().unwrap();
                                pending_events.push(events::Event::SendFailHTLC {
                                        node_id,
                                        msg: fail_msg
                                });

                                true
                        },
                }
        }

        /// Provides a payment preimage in response to a PaymentReceived event, returning true and
        /// generating message events for the net layer to claim the payment, if possible. Thus, you
        /// should probably kick the net layer to go send messages if this returns true!
        pub fn claim_funds(&self, payment_preimage: [u8; 32]) -> bool {
                self.claim_funds_internal(payment_preimage, true)
        }
        pub fn claim_funds_internal(&self, payment_preimage: [u8; 32], from_user: bool) -> bool {
                let mut sha = Sha256::new();
                sha.input(&payment_preimage);
                let mut payment_hash = [0; 32];
                sha.result(&mut payment_hash);

                let mut channel_state = self.channel_state.lock().unwrap();
                let mut pending_htlc = {
                        match channel_state.claimable_htlcs.remove(&payment_hash) {
                                Some(pending_htlc) => pending_htlc,
                                None => return false,
                        }
                };

                match pending_htlc {
                        PendingOutboundHTLC::CycledRoute { source_short_channel_id, incoming_packet_shared_secret, route } => {
                                if from_user { // This was the end hop back to us
                                        pending_htlc = PendingOutboundHTLC::IntermediaryHopData { source_short_channel_id, incoming_packet_shared_secret };
                                        channel_state.claimable_htlcs.insert(payment_hash, PendingOutboundHTLC::OutboundRoute { route });
                                } else { // This came from the first upstream node
                                        // Bank error in our favor! Maybe we should tell the user this somehow???
                                        pending_htlc = PendingOutboundHTLC::OutboundRoute { route };
                                        channel_state.claimable_htlcs.insert(payment_hash, PendingOutboundHTLC::IntermediaryHopData { source_short_channel_id, incoming_packet_shared_secret });
                                }
                        },
                        _ => {},
                }

                match pending_htlc {
                        PendingOutboundHTLC::CycledRoute { .. } => { panic!("WAT"); },
                        PendingOutboundHTLC::OutboundRoute { .. } => {
                                if from_user {
                                        panic!("Called claim_funds with a preimage for an outgoing payment. There is nothing we can do with this, and something is seriously wrong if you knew this...");
                                }
                                mem::drop(channel_state);
                                let mut pending_events = self.pending_events.lock().unwrap();
                                pending_events.push(events::Event::PaymentSent {
                                        payment_preimage
                                });
                                false
                        },
                        PendingOutboundHTLC::IntermediaryHopData { source_short_channel_id, .. } => {
                                let (node_id, fulfill_msg, monitor) = {
                                        let chan_id = match channel_state.short_to_id.get(&source_short_channel_id) {
                                                Some(chan_id) => chan_id.clone(),
                                                None => return false
                                        };

                                        let chan = channel_state.by_id.get_mut(&chan_id).unwrap();
                                        match chan.get_update_fulfill_htlc(payment_preimage) {
                                                Ok(msg) => (chan.get_their_node_id(), msg, if from_user { Some(chan.channel_monitor()) } else { None }),
                                                Err(_e) => {
                                                        //TODO: Do something with e?
                                                        return false;
                                                },
                                        }
                                };

                                {
                                        mem::drop(channel_state);
                                        let mut pending_events = self.pending_events.lock().unwrap();
                                        pending_events.push(events::Event::SendFulfillHTLC {
                                                node_id: node_id,
                                                msg: fulfill_msg
                                        });
                                }

                                //TODO: It may not be possible to handle add_update_monitor fails gracefully, maybe
                                //it should return no Err? Sadly, panic!()s instead doesn't help much :(
                                if from_user {
                                        match self.monitor.add_update_monitor(monitor.as_ref().unwrap().get_funding_txo().unwrap(), monitor.unwrap()) {
                                                Ok(()) => true,
                                                Err(_) => true,
                                        }
                                } else { true }
                        },
                }
        }

        /// Gets the node_id held by this ChannelManager
        pub fn get_our_node_id(&self) -> PublicKey {
                PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).unwrap()
        }
}

impl events::EventsProvider for ChannelManager {
        fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
                let mut pending_events = self.pending_events.lock().unwrap();
                let mut ret = Vec::new();
                mem::swap(&mut ret, &mut *pending_events);
                ret
        }
}

impl ChainListener for ChannelManager {
        fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], indexes_of_txn_matched: &[u32]) {
                let mut new_funding_locked_messages = Vec::new();
                {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        let mut short_to_ids_to_insert = Vec::new();
                        for channel in channel_state.by_id.values_mut() {
                                match channel.block_connected(header, height, txn_matched, indexes_of_txn_matched) {
                                        Some(funding_locked) => {
                                                let announcement_sigs = match self.get_announcement_sigs(channel) {
                                                        Ok(res) => res,
                                                        Err(_e) => {
                                                                //TODO: push e on events and blow up the channel (it has bad keys)
                                                                continue;
                                                        }
                                                };
                                                new_funding_locked_messages.push(events::Event::SendFundingLocked {
                                                        node_id: channel.get_their_node_id(),
                                                        msg: funding_locked,
                                                        announcement_sigs: announcement_sigs
                                                });
                                                short_to_ids_to_insert.push((channel.get_short_channel_id().unwrap(), channel.channel_id()));
                                        },
                                        None => {}
                                }
                                //TODO: Check if channel was closed (or disabled) here
                        }
                        for to_insert in short_to_ids_to_insert {
                                channel_state.short_to_id.insert(to_insert.0, to_insert.1);
                        }
                }
                let mut pending_events = self.pending_events.lock().unwrap();
                for funding_locked in new_funding_locked_messages.drain(..) {
                        pending_events.push(funding_locked);
                }
        }

        fn block_disconnected(&self, header: &BlockHeader) {
                let mut channel_state = self.channel_state.lock().unwrap();
                for channel in channel_state.by_id.values_mut() {
                        if channel.block_disconnected(header) {
                                //TODO Close channel here
                        }
                }
        }
}

impl ChannelMessageHandler for ChannelManager {
        //TODO: Handle errors and close channel (or so)
        fn handle_open_channel(&self, their_node_id: &PublicKey, msg: &msgs::OpenChannel) -> Result<msgs::AcceptChannel, HandleError> {
                if msg.chain_hash != self.genesis_hash {
                        return Err(HandleError{err: "Unknown genesis block hash", msg: None});
                }
                let mut channel_state = self.channel_state.lock().unwrap();
                if channel_state.by_id.contains_key(&msg.temporary_channel_id) {
                        return Err(HandleError{err: "temporary_channel_id collision!", msg: None});
                }
                let channel = Channel::new_from_req(&*self.fee_estimator, their_node_id.clone(), msg, 0, self.announce_channels_publicly)?;
                let accept_msg = channel.get_accept_channel()?;
                channel_state.by_id.insert(channel.channel_id(), channel);
                Ok(accept_msg)
        }

        fn handle_accept_channel(&self, their_node_id: &PublicKey, msg: &msgs::AcceptChannel) -> Result<(), HandleError> {
                let (value, output_script, user_id) = {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        match channel_state.by_id.get_mut(&msg.temporary_channel_id) {
                                Some(chan) => {
                                        if chan.get_their_node_id() != *their_node_id {
                                                return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                        }
                                        chan.accept_channel(&msg)?;
                                        (chan.get_value_satoshis(), chan.get_funding_redeemscript().to_v0_p2wsh(), chan.get_user_id())
                                },
                                None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                        }
                };
                let mut pending_events = self.pending_events.lock().unwrap();
                pending_events.push(events::Event::FundingGenerationReady {
                        temporary_channel_id: msg.temporary_channel_id,
                        channel_value_satoshis: value,
                        output_script: output_script,
                        user_channel_id: user_id,
                });
                Ok(())
        }

        fn handle_funding_created(&self, their_node_id: &PublicKey, msg: &msgs::FundingCreated) -> Result<msgs::FundingSigned, HandleError> {
                //TODO: broke this - a node shouldn't be able to get their channel removed by sending a
                //funding_created a second time, or long after the first, or whatever (note this also
                //leaves the short_to_id map in a busted state.
                let chan = {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        match channel_state.by_id.remove(&msg.temporary_channel_id) {
                                Some(mut chan) => {
                                        if chan.get_their_node_id() != *their_node_id {
                                                return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                        }
                                        match chan.funding_created(msg) {
                                                Ok(funding_msg) => {
                                                        (chan, funding_msg)
                                                },
                                                Err(e) => {
                                                        return Err(e);
                                                }
                                        }
                                },
                                None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                        }
                }; // Release channel lock for install_watch_outpoint call,
                   // note that this means if the remote end is misbehaving and sends a message for the same
                   // channel back-to-back with funding_created, we'll end up thinking they sent a message
                   // for a bogus channel.
                let chan_monitor = chan.0.channel_monitor();
                self.monitor.add_update_monitor(chan_monitor.get_funding_txo().unwrap(), chan_monitor)?;
                let mut channel_state = self.channel_state.lock().unwrap();
                channel_state.by_id.insert(chan.1.channel_id, chan.0);
                Ok(chan.1)
        }

        fn handle_funding_signed(&self, their_node_id: &PublicKey, msg: &msgs::FundingSigned) -> Result<(), HandleError> {
                let (funding_txo, user_id) = {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        match channel_state.by_id.get_mut(&msg.channel_id) {
                                Some(chan) => {
                                        if chan.get_their_node_id() != *their_node_id {
                                                return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                        }
                                        chan.funding_signed(&msg)?;
                                        (chan.get_funding_txo().unwrap(), chan.get_user_id())
                                },
                                None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                        }
                };
                let mut pending_events = self.pending_events.lock().unwrap();
                pending_events.push(events::Event::FundingBroadcastSafe {
                        funding_txo: funding_txo,
                        user_channel_id: user_id,
                });
                Ok(())
        }

        fn handle_funding_locked(&self, their_node_id: &PublicKey, msg: &msgs::FundingLocked) -> Result<Option<msgs::AnnouncementSignatures>, HandleError> {
                let mut channel_state = self.channel_state.lock().unwrap();
                match channel_state.by_id.get_mut(&msg.channel_id) {
                        Some(chan) => {
                                if chan.get_their_node_id() != *their_node_id {
                                        return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                }
                                chan.funding_locked(&msg)?;
                                return Ok(self.get_announcement_sigs(chan)?);
                        },
                        None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                };
        }

        fn handle_shutdown(&self, their_node_id: &PublicKey, msg: &msgs::Shutdown) -> Result<(Option<msgs::Shutdown>, Option<msgs::ClosingSigned>), HandleError> {
                let res = {
                        let mut channel_state = self.channel_state.lock().unwrap();

                        match channel_state.by_id.entry(msg.channel_id.clone()) {
                                hash_map::Entry::Occupied(mut chan_entry) => {
                                        if chan_entry.get().get_their_node_id() != *their_node_id {
                                                return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                        }
                                        let res = chan_entry.get_mut().shutdown(&*self.fee_estimator, &msg)?;
                                        if chan_entry.get().is_shutdown() {
                                                chan_entry.remove_entry();
                                        }
                                        res
                                },
                                hash_map::Entry::Vacant(_) => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                        }
                };
                for payment_hash in res.2 {
                        // unknown_next_peer...I dunno who that is anymore....
                        self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), &payment_hash, HTLCFailReason::Reason { failure_code: 0x4000 | 10, data: &[0; 0] });
                }
                Ok((res.0, res.1))
        }

        fn handle_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) -> Result<Option<msgs::ClosingSigned>, HandleError> {
                let res = {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        match channel_state.by_id.entry(msg.channel_id.clone()) {
                                hash_map::Entry::Occupied(mut chan_entry) => {
                                        if chan_entry.get().get_their_node_id() != *their_node_id {
                                                return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                        }
                                        let res = chan_entry.get_mut().closing_signed(&*self.fee_estimator, &msg)?;
                                        if res.1.is_some() {
                                                // We're done with this channel, we've got a signed closing transaction and
                                                // will send the closing_signed back to the remote peer upon return. This
                                                // also implies there are no pending HTLCs left on the channel, so we can
                                                // fully delete it from tracking (the channel monitor is still around to
                                                // watch for old state broadcasts)!
                                                chan_entry.remove_entry();
                                        }
                                        res
                                },
                                hash_map::Entry::Vacant(_) => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                        }
                };
                if let Some(broadcast_tx) = res.1 {
                        self.tx_broadcaster.broadcast_transaction(&broadcast_tx);
                }
                Ok(res.0)
        }

        fn handle_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) -> Result<(), msgs::HandleError> {
                //TODO: BOLT 4 points out a specific attack where a peer may re-send an onion packet and
                //determine the state of the payment based on our response/if we forward anything/the time
                //we take to respond. We should take care to avoid allowing such an attack.
                //
                //TODO: There exists a further attack where a node may garble the onion data, forward it to
                //us repeatedly garbled in different ways, and compare our error messages, which are
                //encrypted with the same key. Its not immediately obvious how to usefully exploit that,
                //but we should prevent it anyway.

                let shared_secret = SharedSecret::new(&self.secp_ctx, &msg.onion_routing_packet.public_key, &self.our_network_key);
                let (rho, mu) = ChannelManager::gen_rho_mu_from_shared_secret(&shared_secret);

                let associated_data = Vec::new(); //TODO: What to put here?

                macro_rules! get_onion_hash {
                        () => {
                                {
                                        let mut sha = Sha256::new();
                                        sha.input(&msg.onion_routing_packet.hop_data);
                                        let mut onion_hash = [0; 32];
                                        sha.result(&mut onion_hash);
                                        onion_hash
                                }
                        }
                }

                macro_rules! return_err {
                        ($msg: expr, $err_code: expr, $data: expr) => {
                                return Err(msgs::HandleError {
                                        err: $msg,
                                        msg: Some(msgs::ErrorAction::UpdateFailHTLC {
                                                msg: msgs::UpdateFailHTLC {
                                                        channel_id: msg.channel_id,
                                                        htlc_id: msg.htlc_id,
                                                        reason: ChannelManager::build_first_hop_failure_packet(&shared_secret, $err_code, $data),
                                                }
                                        }),
                                });
                        }
                }

                if msg.onion_routing_packet.version != 0 {
                        //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
                        //sha256_of_onion error data packets), or the entire onion_routing_packet. Either way,
                        //the hash doesn't really serve any purpuse - in the case of hashing all data, the
                        //receiving node would have to brute force to figure out which version was put in the
                        //packet by the node that send us the message, in the case of hashing the hop_data, the
                        //node knows the HMAC matched, so they already know what is there...
                        return_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4, &get_onion_hash!());
                }

                let mut hmac = Hmac::new(Sha256::new(), &mu);
                hmac.input(&msg.onion_routing_packet.hop_data);
                hmac.input(&associated_data[..]);
                if hmac.result() != MacResult::new(&msg.onion_routing_packet.hmac) {
                        return_err!("HMAC Check failed", 0x8000 | 0x4000 | 5, &get_onion_hash!());
                }

                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::decode(&decoded[..]) {
                                Err(err) => {
                                        let error_code = match err {
                                                msgs::DecodeError::UnknownRealmByte => 0x4000 | 1,
                                                _ => 0x2000 | 2, // Should never happen
                                        };
                                        return_err!("Unable to decode our hop data", error_code, &[0;0]);
                                },
                                Ok(msg) => msg
                        }
                };

                let mut pending_forward_info = if next_hop_data.hmac == [0; 32] {
                                // OUR PAYMENT!
                                if next_hop_data.data.amt_to_forward != msg.amount_msat {
                                        return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat));
                                }
                                if next_hop_data.data.outgoing_cltv_value != msg.cltv_expiry {
                                        return_err!("Upstream node set CLTV to the wrong value", 18, &byte_utils::be32_to_array(msg.cltv_expiry));
                                }

                                // Note that we could obviously respond immediately with an update_fulfill_htlc
                                // message, however that would leak that we are the recipient of this payment, so
                                // instead we stay symmetric with the forwarding case, only responding (after a
                                // delay) once they've send us a commitment_signed!

                                PendingForwardHTLCInfo {
                                        onion_packet: None,
                                        payment_hash: msg.payment_hash.clone(),
                                        short_channel_id: 0,
                                        prev_short_channel_id: 0,
                                        amt_to_forward: next_hop_data.data.amt_to_forward,
                                        outgoing_cltv_value: next_hop_data.data.outgoing_cltv_value,
                                }
                        } 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(&ChannelManager::ZERO[0..65], &mut new_packet_data[19*65..]);

                                let mut new_pubkey = msg.onion_routing_packet.public_key.clone();

                                let blinding_factor = {
                                        let mut sha = Sha256::new();
                                        sha.input(&new_pubkey.serialize()[..]);
                                        sha.input(&shared_secret[..]);
                                        let mut res = [0u8; 32];
                                        sha.result(&mut res);
                                        match SecretKey::from_slice(&self.secp_ctx, &res) {
                                                Err(_) => {
                                                        // Return temporary node failure as its technically our issue, not the
                                                        // channel's issue.
                                                        return_err!("Blinding factor is an invalid private key", 0x2000 | 2, &[0;0]);
                                                },
                                                Ok(key) => key
                                        }
                                };

                                match new_pubkey.mul_assign(&self.secp_ctx, &blinding_factor) {
                                        Err(_) => {
                                                // Return temporary node failure as its technically our issue, not the
                                                // channel's issue.
                                                return_err!("New blinding factor is an invalid private key", 0x2000 | 2, &[0;0]);
                                        },
                                        Ok(_) => {}
                                };

                                let outgoing_packet = msgs::OnionPacket {
                                        version: 0,
                                        public_key: new_pubkey,
                                        hop_data: new_packet_data,
                                        hmac: next_hop_data.hmac.clone(),
                                };

                                //TODO: Check amt_to_forward and outgoing_cltv_value are within acceptable ranges!

                                PendingForwardHTLCInfo {
                                        onion_packet: Some(outgoing_packet),
                                        payment_hash: msg.payment_hash.clone(),
                                        short_channel_id: next_hop_data.data.short_channel_id,
                                        prev_short_channel_id: 0,
                                        amt_to_forward: next_hop_data.data.amt_to_forward,
                                        outgoing_cltv_value: next_hop_data.data.outgoing_cltv_value,
                                }
                        };

                let mut channel_state_lock = self.channel_state.lock().unwrap();
                let channel_state = channel_state_lock.borrow_parts();

                if pending_forward_info.onion_packet.is_some() { // If short_channel_id is 0 here, we'll reject them in the body here
                        let forwarding_id = match channel_state.short_to_id.get(&pending_forward_info.short_channel_id) {
                                None => {
                                        return_err!("Don't have available channel for forwarding as requested.", 0x4000 | 10, &[0;0]);
                                },
                                Some(id) => id.clone(),
                        };
                        let chan = channel_state.by_id.get_mut(&forwarding_id).unwrap();
                        if !chan.is_live() {
                                let chan_update = self.get_channel_update(chan).unwrap();
                                return_err!("Forwarding channel is not in a ready state.", 0x4000 | 10, &chan_update.encode()[..]);
                        }
                }

                let claimable_htlcs_entry = channel_state.claimable_htlcs.entry(msg.payment_hash.clone());

                // We dont correctly handle payments that route through us twice on their way to their
                // destination. That's OK since those nodes are probably busted or trying to do network
                // mapping through repeated loops. In either case, we want them to stop talking to us, so
                // we send permanent_node_failure.
                match &claimable_htlcs_entry {
                        &hash_map::Entry::Occupied(ref e) => {
                                let mut acceptable_cycle = false;
                                match e.get() {
                                        &PendingOutboundHTLC::OutboundRoute { .. } => {
                                                acceptable_cycle = pending_forward_info.short_channel_id == 0;
                                        },
                                        _ => {},
                                }
                                if !acceptable_cycle {
                                        return_err!("Payment looped through us twice", 0x4000 | 0x2000 | 2, &[0;0]);
                                }
                        },
                        _ => {},
                }

                let (source_short_channel_id, res) = match channel_state.by_id.get_mut(&msg.channel_id) {
                        Some(chan) => {
                                if chan.get_their_node_id() != *their_node_id {
                                        return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                }
                                if !chan.is_usable() {
                                        return Err(HandleError{err: "Channel not yet available for receiving HTLCs", msg: None});
                                }
                                let short_channel_id = chan.get_short_channel_id().unwrap();
                                pending_forward_info.prev_short_channel_id = short_channel_id;
                                (short_channel_id, chan.update_add_htlc(&msg, pending_forward_info)?)
                        },
                        None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None}), //TODO: panic?
                };

                match claimable_htlcs_entry {
                        hash_map::Entry::Occupied(mut e) => {
                                let outbound_route = e.get_mut();
                                let route = match outbound_route {
                                        &mut PendingOutboundHTLC::OutboundRoute { ref route } => {
                                                route.clone()
                                        },
                                        _ => { panic!("WAT") },
                                };
                                *outbound_route = PendingOutboundHTLC::CycledRoute {
                                        source_short_channel_id,
                                        incoming_packet_shared_secret: shared_secret,
                                        route
                                };
                        },
                        hash_map::Entry::Vacant(e) => {
                                e.insert(PendingOutboundHTLC::IntermediaryHopData {
                                        source_short_channel_id,
                                        incoming_packet_shared_secret: shared_secret,
                                });
                        }
                }

                Ok(res)
        }

        fn handle_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) -> Result<(), HandleError> {
                let monitor = {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        match channel_state.by_id.get_mut(&msg.channel_id) {
                                Some(chan) => {
                                        if chan.get_their_node_id() != *their_node_id {
                                                return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                        }
                                        chan.update_fulfill_htlc(&msg)?;
                                        chan.channel_monitor()
                                },
                                None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                        }
                };
                //TODO: Delay the claimed_funds relaying just like we do outbound relay!
                self.claim_funds_internal(msg.payment_preimage.clone(), false);
                self.monitor.add_update_monitor(monitor.get_funding_txo().unwrap(), monitor)?;
                Ok(())
        }

        fn handle_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<(), HandleError> {
                let mut channel_state = self.channel_state.lock().unwrap();
                let payment_hash = match channel_state.by_id.get_mut(&msg.channel_id) {
                        Some(chan) => {
                                if chan.get_their_node_id() != *their_node_id {
                                        return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                }
                                chan.update_fail_htlc(&msg)?
                        },
                        None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                };
                self.fail_htlc_backwards_internal(channel_state, &payment_hash, HTLCFailReason::ErrorPacket { err: &msg.reason });
                Ok(())
        }

        fn handle_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) -> Result<(), HandleError> {
                let mut channel_state = self.channel_state.lock().unwrap();
                let payment_hash = match channel_state.by_id.get_mut(&msg.channel_id) {
                        Some(chan) => {
                                if chan.get_their_node_id() != *their_node_id {
                                        return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                }
                                chan.update_fail_malformed_htlc(&msg)?
                        },
                        None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                };
                self.fail_htlc_backwards_internal(channel_state, &payment_hash, HTLCFailReason::Reason { failure_code: msg.failure_code, data: &[0;0] });
                Ok(())
        }

        fn handle_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) -> Result<msgs::RevokeAndACK, HandleError> {
                let mut forward_event = None;
                let (res, monitor) = {
                        let mut channel_state = self.channel_state.lock().unwrap();

                        let ((res, mut forwarding_infos), monitor) = match channel_state.by_id.get_mut(&msg.channel_id) {
                                Some(chan) => {
                                        if chan.get_their_node_id() != *their_node_id {
                                                return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                        }
                                        (chan.commitment_signed(&msg)?, chan.channel_monitor())
                                },
                                None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                        };

                        if channel_state.forward_htlcs.is_empty() {
                                forward_event = Some(Instant::now() + Duration::from_millis(((rng::rand_f32() * 4.0 + 1.0) * MIN_HTLC_RELAY_HOLDING_CELL_MILLIS as f32) as u64));
                                channel_state.next_forward = forward_event.unwrap();
                        }
                        for forward_info in forwarding_infos.drain(..) {
                                match channel_state.forward_htlcs.entry(forward_info.short_channel_id) {
                                        hash_map::Entry::Occupied(mut entry) => {
                                                entry.get_mut().push(forward_info);
                                        },
                                        hash_map::Entry::Vacant(entry) => {
                                                entry.insert(vec!(forward_info));
                                        }
                                }
                        }

                        (res, monitor)
                };
                //TODO: Only if we store HTLC sigs
                self.monitor.add_update_monitor(monitor.get_funding_txo().unwrap(), monitor)?;

                match forward_event {
                        Some(time) => {
                                let mut pending_events = self.pending_events.lock().unwrap();
                                pending_events.push(events::Event::PendingHTLCsForwardable {
                                        time_forwardable: time
                                });
                        }
                        None => {},
                }

                Ok(res)
        }

        fn handle_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<Option<(Vec<msgs::UpdateAddHTLC>, msgs::CommitmentSigned)>, HandleError> {
                let (res, monitor) = {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        match channel_state.by_id.get_mut(&msg.channel_id) {
                                Some(chan) => {
                                        if chan.get_their_node_id() != *their_node_id {
                                                return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                        }
                                        (chan.revoke_and_ack(&msg)?, chan.channel_monitor())
                                },
                                None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                        }
                };
                self.monitor.add_update_monitor(monitor.get_funding_txo().unwrap(), monitor)?;
                Ok(res)
        }

        fn handle_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) -> Result<(), HandleError> {
                let mut channel_state = self.channel_state.lock().unwrap();
                match channel_state.by_id.get_mut(&msg.channel_id) {
                        Some(chan) => {
                                if chan.get_their_node_id() != *their_node_id {
                                        return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                }
                                chan.update_fee(&*self.fee_estimator, &msg)
                        },
                        None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                }
        }

        fn handle_announcement_signatures(&self, their_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) -> Result<(), HandleError> {
                let (chan_announcement, chan_update) = {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        match channel_state.by_id.get_mut(&msg.channel_id) {
                                Some(chan) => {
                                        if chan.get_their_node_id() != *their_node_id {
                                                return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                        }
                                        if !chan.is_usable() {
                                                return Err(HandleError{err: "Got an announcement_signatures before we were ready for it", msg: None });
                                        }

                                        let our_node_id = self.get_our_node_id();
                                        let (announcement, our_bitcoin_sig) = chan.get_channel_announcement(our_node_id.clone(), self.genesis_hash.clone())?;

                                        let were_node_one = announcement.node_id_1 == our_node_id;
                                        let msghash = Message::from_slice(&Sha256dHash::from_data(&announcement.encode()[..])[..]).unwrap();
                                        secp_call!(self.secp_ctx.verify(&msghash, &msg.node_signature, if were_node_one { &announcement.node_id_2 } else { &announcement.node_id_1 }));
                                        secp_call!(self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, if were_node_one { &announcement.bitcoin_key_2 } else { &announcement.bitcoin_key_1 }));

                                        let our_node_sig = secp_call!(self.secp_ctx.sign(&msghash, &self.our_network_key));

                                        (msgs::ChannelAnnouncement {
                                                node_signature_1: if were_node_one { our_node_sig } else { msg.node_signature },
                                                node_signature_2: if were_node_one { msg.node_signature } else { our_node_sig },
                                                bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { msg.bitcoin_signature },
                                                bitcoin_signature_2: if were_node_one { msg.bitcoin_signature } else { our_bitcoin_sig },
                                                contents: announcement,
                                        }, self.get_channel_update(chan).unwrap()) // can only fail if we're not in a ready state
                                },
                                None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                        }
                };
                let mut pending_events = self.pending_events.lock().unwrap();
                pending_events.push(events::Event::BroadcastChannelAnnouncement { msg: chan_announcement, update_msg: chan_update });
                Ok(())
        }

        fn peer_disconnected(&self, their_node_id: &PublicKey, no_connection_possible: bool) {
                let mut channel_state_lock = self.channel_state.lock().unwrap();
                let channel_state = channel_state_lock.borrow_parts();
                let short_to_id = channel_state.short_to_id;
                if no_connection_possible {
                        channel_state.by_id.retain(move |_, chan| {
                                if chan.get_their_node_id() == *their_node_id {
                                        match chan.get_short_channel_id() {
                                                Some(short_id) => {
                                                        short_to_id.remove(&short_id);
                                                },
                                                None => {},
                                        }
                                        //TODO: get the latest commitment tx, any HTLC txn built on top of it, etc out
                                        //of the channel and throw those into the announcement blackhole.
                                        false
                                } else {
                                        true
                                }
                        });
                } else {
                        for chan in channel_state.by_id {
                                if chan.1.get_their_node_id() == *their_node_id {
                                        //TODO: mark channel disabled (and maybe announce such after a timeout). Also
                                        //fail and wipe any uncommitted outbound HTLCs as those are considered after
                                        //reconnect.
                                }
                        }
                }
        }
}

#[cfg(test)]
mod tests {
        use chain::chaininterface;
        use ln::channelmanager::{ChannelManager,OnionKeys};
        use ln::router::{Route, RouteHop, Router};
        use ln::msgs;
        use ln::msgs::{MsgEncodable,ChannelMessageHandler,RoutingMessageHandler};
        use util::test_utils;
        use util::events::{Event, EventsProvider};

        use bitcoin::util::misc::hex_bytes;
        use bitcoin::util::hash::Sha256dHash;
        use bitcoin::util::uint::Uint256;
        use bitcoin::blockdata::block::BlockHeader;
        use bitcoin::blockdata::transaction::{Transaction, TxOut};
        use bitcoin::network::constants::Network;
        use bitcoin::network::serialize::serialize;
        use bitcoin::network::serialize::BitcoinHash;

        use secp256k1::Secp256k1;
        use secp256k1::key::{PublicKey,SecretKey};

        use crypto::sha2::Sha256;
        use crypto::digest::Digest;

        use rand::{thread_rng,Rng};

        use std::sync::{Arc, Mutex};
        use std::default::Default;
        use std::time::Instant;

        fn build_test_onion_keys() -> Vec<OnionKeys> {
                // Keys from BOLT 4, used in both test vector tests
                let secp_ctx = Secp256k1::new();

                let route = Route {
                        hops: vec!(
                                        RouteHop {
                                                pubkey: PublicKey::from_slice(&secp_ctx, &hex_bytes("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
                                                short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
                                        },
                                        RouteHop {
                                                pubkey: PublicKey::from_slice(&secp_ctx, &hex_bytes("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
                                                short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
                                        },
                                        RouteHop {
                                                pubkey: PublicKey::from_slice(&secp_ctx, &hex_bytes("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
                                                short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
                                        },
                                        RouteHop {
                                                pubkey: PublicKey::from_slice(&secp_ctx, &hex_bytes("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]).unwrap(),
                                                short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
                                        },
                                        RouteHop {
                                                pubkey: PublicKey::from_slice(&secp_ctx, &hex_bytes("02edabbd16b41c8371b92ef2f04c1185b4f03b6dcd52ba9b78d9d7c89c8f221145").unwrap()[..]).unwrap(),
                                                short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
                                        },
                        ),
                };

                let session_priv = SecretKey::from_slice(&secp_ctx, &hex_bytes("4141414141414141414141414141414141414141414141414141414141414141").unwrap()[..]).unwrap();

                let onion_keys = ChannelManager::construct_onion_keys(&secp_ctx, &route, &session_priv).unwrap();
                assert_eq!(onion_keys.len(), route.hops.len());
                onion_keys
        }

        #[test]
        fn onion_vectors() {
                // Packet creation test vectors from BOLT 4
                let onion_keys = build_test_onion_keys();

                assert_eq!(onion_keys[0].shared_secret[..], hex_bytes("53eb63ea8a3fec3b3cd433b85cd62a4b145e1dda09391b348c4e1cd36a03ea66").unwrap()[..]);
                assert_eq!(onion_keys[0].blinding_factor[..], hex_bytes("2ec2e5da605776054187180343287683aa6a51b4b1c04d6dd49c45d8cffb3c36").unwrap()[..]);
                assert_eq!(onion_keys[0].ephemeral_pubkey.serialize()[..], hex_bytes("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]);
                assert_eq!(onion_keys[0].rho, hex_bytes("ce496ec94def95aadd4bec15cdb41a740c9f2b62347c4917325fcc6fb0453986").unwrap()[..]);
                assert_eq!(onion_keys[0].mu, hex_bytes("b57061dc6d0a2b9f261ac410c8b26d64ac5506cbba30267a649c28c179400eba").unwrap()[..]);

                assert_eq!(onion_keys[1].shared_secret[..], hex_bytes("a6519e98832a0b179f62123b3567c106db99ee37bef036e783263602f3488fae").unwrap()[..]);
                assert_eq!(onion_keys[1].blinding_factor[..], hex_bytes("bf66c28bc22e598cfd574a1931a2bafbca09163df2261e6d0056b2610dab938f").unwrap()[..]);
                assert_eq!(onion_keys[1].ephemeral_pubkey.serialize()[..], hex_bytes("028f9438bfbf7feac2e108d677e3a82da596be706cc1cf342b75c7b7e22bf4e6e2").unwrap()[..]);
                assert_eq!(onion_keys[1].rho, hex_bytes("450ffcabc6449094918ebe13d4f03e433d20a3d28a768203337bc40b6e4b2c59").unwrap()[..]);
                assert_eq!(onion_keys[1].mu, hex_bytes("05ed2b4a3fb023c2ff5dd6ed4b9b6ea7383f5cfe9d59c11d121ec2c81ca2eea9").unwrap()[..]);

                assert_eq!(onion_keys[2].shared_secret[..], hex_bytes("3a6b412548762f0dbccce5c7ae7bb8147d1caf9b5471c34120b30bc9c04891cc").unwrap()[..]);
                assert_eq!(onion_keys[2].blinding_factor[..], hex_bytes("a1f2dadd184eb1627049673f18c6325814384facdee5bfd935d9cb031a1698a5").unwrap()[..]);
                assert_eq!(onion_keys[2].ephemeral_pubkey.serialize()[..], hex_bytes("03bfd8225241ea71cd0843db7709f4c222f62ff2d4516fd38b39914ab6b83e0da0").unwrap()[..]);
                assert_eq!(onion_keys[2].rho, hex_bytes("11bf5c4f960239cb37833936aa3d02cea82c0f39fd35f566109c41f9eac8deea").unwrap()[..]);
                assert_eq!(onion_keys[2].mu, hex_bytes("caafe2820fa00eb2eeb78695ae452eba38f5a53ed6d53518c5c6edf76f3f5b78").unwrap()[..]);

                assert_eq!(onion_keys[3].shared_secret[..], hex_bytes("21e13c2d7cfe7e18836df50872466117a295783ab8aab0e7ecc8c725503ad02d").unwrap()[..]);
                assert_eq!(onion_keys[3].blinding_factor[..], hex_bytes("7cfe0b699f35525029ae0fa437c69d0f20f7ed4e3916133f9cacbb13c82ff262").unwrap()[..]);
                assert_eq!(onion_keys[3].ephemeral_pubkey.serialize()[..], hex_bytes("031dde6926381289671300239ea8e57ffaf9bebd05b9a5b95beaf07af05cd43595").unwrap()[..]);
                assert_eq!(onion_keys[3].rho, hex_bytes("cbe784ab745c13ff5cffc2fbe3e84424aa0fd669b8ead4ee562901a4a4e89e9e").unwrap()[..]);
                assert_eq!(onion_keys[3].mu, hex_bytes("5052aa1b3d9f0655a0932e50d42f0c9ba0705142c25d225515c45f47c0036ee9").unwrap()[..]);

                assert_eq!(onion_keys[4].shared_secret[..], hex_bytes("b5756b9b542727dbafc6765a49488b023a725d631af688fc031217e90770c328").unwrap()[..]);
                assert_eq!(onion_keys[4].blinding_factor[..], hex_bytes("c96e00dddaf57e7edcd4fb5954be5b65b09f17cb6d20651b4e90315be5779205").unwrap()[..]);
                assert_eq!(onion_keys[4].ephemeral_pubkey.serialize()[..], hex_bytes("03a214ebd875aab6ddfd77f22c5e7311d7f77f17a169e599f157bbcdae8bf071f4").unwrap()[..]);
                assert_eq!(onion_keys[4].rho, hex_bytes("034e18b8cc718e8af6339106e706c52d8df89e2b1f7e9142d996acf88df8799b").unwrap()[..]);
                assert_eq!(onion_keys[4].mu, hex_bytes("8e45e5c61c2b24cb6382444db6698727afb063adecd72aada233d4bf273d975a").unwrap()[..]);

                // Test vectors below are flat-out wrong: they claim to set outgoing_cltv_value to non-0 :/
                let payloads = vec!(
                        msgs::OnionHopData {
                                realm: 0,
                                data: msgs::OnionRealm0HopData {
                                        short_channel_id: 0,
                                        amt_to_forward: 0,
                                        outgoing_cltv_value: 0,
                                },
                                hmac: [0; 32],
                        },
                        msgs::OnionHopData {
                                realm: 0,
                                data: msgs::OnionRealm0HopData {
                                        short_channel_id: 0x0101010101010101,
                                        amt_to_forward: 0x0100000001,
                                        outgoing_cltv_value: 0,
                                },
                                hmac: [0; 32],
                        },
                        msgs::OnionHopData {
                                realm: 0,
                                data: msgs::OnionRealm0HopData {
                                        short_channel_id: 0x0202020202020202,
                                        amt_to_forward: 0x0200000002,
                                        outgoing_cltv_value: 0,
                                },
                                hmac: [0; 32],
                        },
                        msgs::OnionHopData {
                                realm: 0,
                                data: msgs::OnionRealm0HopData {
                                        short_channel_id: 0x0303030303030303,
                                        amt_to_forward: 0x0300000003,
                                        outgoing_cltv_value: 0,
                                },
                                hmac: [0; 32],
                        },
                        msgs::OnionHopData {
                                realm: 0,
                                data: msgs::OnionRealm0HopData {
                                        short_channel_id: 0x0404040404040404,
                                        amt_to_forward: 0x0400000004,
                                        outgoing_cltv_value: 0,
                                },
                                hmac: [0; 32],
                        },
                );

                let packet = ChannelManager::construct_onion_packet(payloads, onion_keys, hex_bytes("4242424242424242424242424242424242424242424242424242424242424242").unwrap()).unwrap();
                // Just check the final packet encoding, as it includes all the per-hop vectors in it
                // anyway...
                assert_eq!(packet.encode(), hex_bytes("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").unwrap());
        }

        #[test]
        fn test_failure_packet_onion() {
                // Returning Errors test vectors from BOLT 4

                let onion_keys = build_test_onion_keys();
                let onion_error = ChannelManager::build_failure_packet(&onion_keys[4].shared_secret, 0x2002, &[0; 0]);
                assert_eq!(onion_error.encode(), hex_bytes("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").unwrap());

                let onion_packet_1 = ChannelManager::encrypt_failure_packet(&onion_keys[4].shared_secret, &onion_error.encode()[..]);
                assert_eq!(onion_packet_1.data, hex_bytes("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").unwrap());

                let onion_packet_2 = ChannelManager::encrypt_failure_packet(&onion_keys[3].shared_secret, &onion_packet_1.data[..]);
                assert_eq!(onion_packet_2.data, hex_bytes("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").unwrap());

                let onion_packet_3 = ChannelManager::encrypt_failure_packet(&onion_keys[2].shared_secret, &onion_packet_2.data[..]);
                assert_eq!(onion_packet_3.data, hex_bytes("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").unwrap());

                let onion_packet_4 = ChannelManager::encrypt_failure_packet(&onion_keys[1].shared_secret, &onion_packet_3.data[..]);
                assert_eq!(onion_packet_4.data, hex_bytes("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").unwrap());

                let onion_packet_5 = ChannelManager::encrypt_failure_packet(&onion_keys[0].shared_secret, &onion_packet_4.data[..]);
                assert_eq!(onion_packet_5.data, hex_bytes("9c5add3963fc7f6ed7f148623c84134b5647e1306419dbe2174e523fa9e2fbed3a06a19f899145610741c83ad40b7712aefaddec8c6baf7325d92ea4ca4d1df8bce517f7e54554608bf2bd8071a4f52a7a2f7ffbb1413edad81eeea5785aa9d990f2865dc23b4bc3c301a94eec4eabebca66be5cf638f693ec256aec514620cc28ee4a94bd9565bc4d4962b9d3641d4278fb319ed2b84de5b665f307a2db0f7fbb757366067d88c50f7e829138fde4f78d39b5b5802f1b92a8a820865af5cc79f9f30bc3f461c66af95d13e5e1f0381c184572a91dee1c849048a647a1158cf884064deddbf1b0b88dfe2f791428d0ba0f6fb2f04e14081f69165ae66d9297c118f0907705c9c4954a199bae0bb96fad763d690e7daa6cfda59ba7f2c8d11448b604d12d").unwrap());
        }

        static mut CHAN_COUNT: u16 = 0;
        fn confirm_transaction(chain: &chaininterface::ChainWatchInterfaceUtil, tx: &Transaction) {
                let mut header = BlockHeader { version: 0x20000000, prev_blockhash: Default::default(), merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 };
                let chan_id = unsafe { CHAN_COUNT };
                chain.block_connected_checked(&header, 1, &[tx; 1], &[chan_id as u32; 1]);
                for i in 2..100 {
                        header = BlockHeader { version: 0x20000000, prev_blockhash: header.bitcoin_hash(), merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 };
                        chain.block_connected_checked(&header, i, &[tx; 0], &[0; 0]);
                }
        }

        fn create_chan_between_nodes(node_a: &ChannelManager, chain_a: &chaininterface::ChainWatchInterfaceUtil, monitor_a: &test_utils::TestChannelMonitor, node_b: &ChannelManager, chain_b: &chaininterface::ChainWatchInterfaceUtil, monitor_b: &test_utils::TestChannelMonitor) -> (msgs::ChannelAnnouncement, msgs::ChannelUpdate, msgs::ChannelUpdate, Uint256) {
                let open_chan = node_a.create_channel(node_b.get_our_node_id(), 100000, 42).unwrap();
                let accept_chan = node_b.handle_open_channel(&node_a.get_our_node_id(), &open_chan).unwrap();
                node_a.handle_accept_channel(&node_b.get_our_node_id(), &accept_chan).unwrap();

                let chan_id = unsafe { CHAN_COUNT };
                let tx;
                let funding_output;

                let events_1 = node_a.get_and_clear_pending_events();
                assert_eq!(events_1.len(), 1);
                match events_1[0] {
                        Event::FundingGenerationReady { ref temporary_channel_id, ref channel_value_satoshis, ref output_script, user_channel_id } => {
                                assert_eq!(*channel_value_satoshis, 100000);
                                assert_eq!(user_channel_id, 42);

                                tx = Transaction { version: chan_id as u32, lock_time: 0, input: Vec::new(), output: vec![TxOut {
                                        value: *channel_value_satoshis, script_pubkey: output_script.clone(),
                                }]};
                                funding_output = (Sha256dHash::from_data(&serialize(&tx).unwrap()[..]), 0);

                                node_a.funding_transaction_generated(&temporary_channel_id, funding_output.clone());
                                let mut added_monitors = monitor_a.added_monitors.lock().unwrap();
                                assert_eq!(added_monitors.len(), 1);
                                assert_eq!(added_monitors[0].0, funding_output);
                                added_monitors.clear();
                        },
                        _ => panic!("Unexpected event"),
                }

                let events_2 = node_a.get_and_clear_pending_events();
                assert_eq!(events_2.len(), 1);
                let funding_signed = match events_2[0] {
                        Event::SendFundingCreated { ref node_id, ref msg } => {
                                assert_eq!(*node_id, node_b.get_our_node_id());
                                let res = node_b.handle_funding_created(&node_a.get_our_node_id(), msg).unwrap();
                                let mut added_monitors = monitor_b.added_monitors.lock().unwrap();
                                assert_eq!(added_monitors.len(), 1);
                                assert_eq!(added_monitors[0].0, funding_output);
                                added_monitors.clear();
                                res
                        },
                        _ => panic!("Unexpected event"),
                };

                node_a.handle_funding_signed(&node_b.get_our_node_id(), &funding_signed).unwrap();

                let events_3 = node_a.get_and_clear_pending_events();
                assert_eq!(events_3.len(), 1);
                match events_3[0] {
                        Event::FundingBroadcastSafe { ref funding_txo, user_channel_id } => {
                                assert_eq!(user_channel_id, 42);
                                assert_eq!(*funding_txo, funding_output);
                        },
                        _ => panic!("Unexpected event"),
                };

                confirm_transaction(&chain_a, &tx);
                let events_4 = node_a.get_and_clear_pending_events();
                assert_eq!(events_4.len(), 1);
                match events_4[0] {
                        Event::SendFundingLocked { ref node_id, ref msg, ref announcement_sigs } => {
                                assert_eq!(*node_id, node_b.get_our_node_id());
                                assert!(announcement_sigs.is_none());
                                node_b.handle_funding_locked(&node_a.get_our_node_id(), msg).unwrap()
                        },
                        _ => panic!("Unexpected event"),
                };

                let channel_id;

                confirm_transaction(&chain_b, &tx);
                let events_5 = node_b.get_and_clear_pending_events();
                assert_eq!(events_5.len(), 1);
                let as_announcement_sigs = match events_5[0] {
                        Event::SendFundingLocked { ref node_id, ref msg, ref announcement_sigs } => {
                                assert_eq!(*node_id, node_a.get_our_node_id());
                                channel_id = msg.channel_id.clone();
                                let as_announcement_sigs = node_a.handle_funding_locked(&node_b.get_our_node_id(), msg).unwrap().unwrap();
                                node_a.handle_announcement_signatures(&node_b.get_our_node_id(), &(*announcement_sigs).clone().unwrap()).unwrap();
                                as_announcement_sigs
                        },
                        _ => panic!("Unexpected event"),
                };

                let events_6 = node_a.get_and_clear_pending_events();
                assert_eq!(events_6.len(), 1);
                let (announcement, as_update) = match events_6[0] {
                        Event::BroadcastChannelAnnouncement { ref msg, ref update_msg } => {
                                (msg, update_msg)
                        },
                        _ => panic!("Unexpected event"),
                };

                node_b.handle_announcement_signatures(&node_a.get_our_node_id(), &as_announcement_sigs).unwrap();
                let events_7 = node_b.get_and_clear_pending_events();
                assert_eq!(events_7.len(), 1);
                let bs_update = match events_7[0] {
                        Event::BroadcastChannelAnnouncement { ref msg, ref update_msg } => {
                                assert!(*announcement == *msg);
                                update_msg
                        },
                        _ => panic!("Unexpected event"),
                };

                unsafe {
                        CHAN_COUNT += 1;
                }

                ((*announcement).clone(), (*as_update).clone(), (*bs_update).clone(), channel_id)
        }

        fn close_channel(outbound_node: &ChannelManager, outbound_broadcaster: &test_utils::TestBroadcaster, inbound_node: &ChannelManager, inbound_broadcaster: &test_utils::TestBroadcaster, channel_id: &Uint256, close_inbound_first: bool) {
                let (node_a, broadcaster_a) = if close_inbound_first { (inbound_node, inbound_broadcaster) } else { (outbound_node, outbound_broadcaster) };
                let (node_b, broadcaster_b) = if close_inbound_first { (outbound_node, outbound_broadcaster) } else { (inbound_node, inbound_broadcaster) };
                let (tx_a, tx_b);

                let shutdown_a = node_a.close_channel(channel_id).unwrap();
                let (shutdown_b, mut closing_signed_b) = node_b.handle_shutdown(&node_a.get_our_node_id(), &shutdown_a).unwrap();
                if !close_inbound_first {
                        assert!(closing_signed_b.is_none());
                }
                let (empty_a, mut closing_signed_a) = node_a.handle_shutdown(&node_b.get_our_node_id(), &shutdown_b.unwrap()).unwrap();
                assert!(empty_a.is_none());
                if close_inbound_first {
                        assert!(closing_signed_a.is_none());
                        closing_signed_a = node_a.handle_closing_signed(&node_b.get_our_node_id(), &closing_signed_b.unwrap()).unwrap();
                        assert_eq!(broadcaster_a.txn_broadcasted.lock().unwrap().len(), 1);
                        tx_a = broadcaster_a.txn_broadcasted.lock().unwrap().remove(0);

                        let empty_b = node_b.handle_closing_signed(&node_a.get_our_node_id(), &closing_signed_a.unwrap()).unwrap();
                        assert!(empty_b.is_none());
                        assert_eq!(broadcaster_b.txn_broadcasted.lock().unwrap().len(), 1);
                        tx_b = broadcaster_b.txn_broadcasted.lock().unwrap().remove(0);
                } else {
                        closing_signed_b = node_b.handle_closing_signed(&node_a.get_our_node_id(), &closing_signed_a.unwrap()).unwrap();
                        assert_eq!(broadcaster_b.txn_broadcasted.lock().unwrap().len(), 1);
                        tx_b = broadcaster_b.txn_broadcasted.lock().unwrap().remove(0);

                        let empty_a2 = node_a.handle_closing_signed(&node_b.get_our_node_id(), &closing_signed_b.unwrap()).unwrap();
                        assert!(empty_a2.is_none());
                        assert_eq!(broadcaster_a.txn_broadcasted.lock().unwrap().len(), 1);
                        tx_a = broadcaster_a.txn_broadcasted.lock().unwrap().remove(0);
                }
                assert_eq!(tx_a, tx_b);
        }

        struct SendEvent {
                node_id: PublicKey,
                msgs: Vec<msgs::UpdateAddHTLC>,
                commitment_msg: msgs::CommitmentSigned,
        }
        impl SendEvent {
                fn from_event(event: Event) -> SendEvent {
                        match event {
                                Event::SendHTLCs { node_id, msgs, commitment_msg } => {
                                        SendEvent { node_id: node_id, msgs: msgs, commitment_msg: commitment_msg }
                                },
                                _ => panic!("Unexpected event type!"),
                        }
                }
        }

        static mut PAYMENT_COUNT: u8 = 0;
        fn send_along_route(origin_node: &ChannelManager, origin_monitor: &test_utils::TestChannelMonitor, route: Route, expected_route: &[(&ChannelManager, &test_utils::TestChannelMonitor)], recv_value: u64) -> ([u8; 32], [u8; 32]) {
                let our_payment_preimage = unsafe { [PAYMENT_COUNT; 32] };
                unsafe { PAYMENT_COUNT += 1 };
                let our_payment_hash = {
                        let mut sha = Sha256::new();
                        sha.input(&our_payment_preimage[..]);
                        let mut ret = [0; 32];
                        sha.result(&mut ret);
                        ret
                };

                let mut payment_event = {
                        let msgs = origin_node.send_payment(route, our_payment_hash).unwrap().unwrap();
                        SendEvent {
                                node_id: expected_route[0].0.get_our_node_id(),
                                msgs: vec!(msgs.0),
                                commitment_msg: msgs.1,
                        }
                };
                let mut prev_node = (origin_node, origin_monitor);

                for (idx, &(node, monitor)) in expected_route.iter().enumerate() {
                        assert_eq!(node.get_our_node_id(), payment_event.node_id);

                        node.handle_update_add_htlc(&prev_node.0.get_our_node_id(), &payment_event.msgs[0]).unwrap();
                        {
                                let added_monitors = monitor.added_monitors.lock().unwrap();
                                assert_eq!(added_monitors.len(), 0);
                        }

                        let revoke_and_ack = node.handle_commitment_signed(&prev_node.0.get_our_node_id(), &payment_event.commitment_msg).unwrap();
                        {
                                let mut added_monitors = monitor.added_monitors.lock().unwrap();
                                assert_eq!(added_monitors.len(), 1);
                                added_monitors.clear();
                        }
                        assert!(prev_node.0.handle_revoke_and_ack(&node.get_our_node_id(), &revoke_and_ack).unwrap().is_none());
                        {
                                let mut added_monitors = prev_node.1.added_monitors.lock().unwrap();
                                assert_eq!(added_monitors.len(), 1);
                                added_monitors.clear();
                        }

                        let events_1 = node.get_and_clear_pending_events();
                        assert_eq!(events_1.len(), 1);
                        match events_1[0] {
                                Event::PendingHTLCsForwardable { .. } => { },
                                _ => panic!("Unexpected event"),
                        };

                        node.channel_state.lock().unwrap().next_forward = Instant::now();
                        node.process_pending_htlc_forward();

                        let mut events_2 = node.get_and_clear_pending_events();
                        assert_eq!(events_2.len(), 1);
                        if idx == expected_route.len() - 1 {
                                match events_2[0] {
                                        Event::PaymentReceived { ref payment_hash, amt } => {
                                                assert_eq!(our_payment_hash, *payment_hash);
                                                assert_eq!(amt, recv_value);
                                        },
                                        _ => panic!("Unexpected event"),
                                }
                        } else {
                                for event in events_2.drain(..) {
                                        payment_event = SendEvent::from_event(event);
                                }
                                assert_eq!(payment_event.msgs.len(), 1);
                        }

                        prev_node = (node, monitor);
                }

                (our_payment_preimage, our_payment_hash)
        }

        fn claim_payment(origin_node: &ChannelManager, origin_monitor: &test_utils::TestChannelMonitor, expected_route: &[(&ChannelManager, &test_utils::TestChannelMonitor)], our_payment_preimage: [u8; 32]) {
                assert!(expected_route.last().unwrap().0.claim_funds(our_payment_preimage));
                {
                        let mut added_monitors = expected_route.last().unwrap().1.added_monitors.lock().unwrap();
                        assert_eq!(added_monitors.len(), 1);
                        added_monitors.clear();
                }

                let mut expected_next_node = expected_route.last().unwrap().0.get_our_node_id();
                let mut prev_node = expected_route.last().unwrap().0;
                let mut next_msg = None;
                for &(node, monitor) in expected_route.iter().rev() {
                        assert_eq!(expected_next_node, node.get_our_node_id());
                        match next_msg {
                                Some(msg) => {
                                        node.handle_update_fulfill_htlc(&prev_node.get_our_node_id(), &msg).unwrap();
                                        {
                                                let mut added_monitors = monitor.added_monitors.lock().unwrap();
                                                assert_eq!(added_monitors.len(), 1);
                                                added_monitors.clear();
                                        }
                                }, None => {}
                        }

                        let events = node.get_and_clear_pending_events();
                        assert_eq!(events.len(), 1);
                        match events[0] {
                                Event::SendFulfillHTLC { ref node_id, ref msg } => {
                                        expected_next_node = node_id.clone();
                                        next_msg = Some(msg.clone());
                                },
                                _ => panic!("Unexpected event"),
                        };

                        prev_node = node;
                }

                assert_eq!(expected_next_node, origin_node.get_our_node_id());
                origin_node.handle_update_fulfill_htlc(&expected_route.first().unwrap().0.get_our_node_id(), &next_msg.unwrap()).unwrap();
                {
                        let mut added_monitors = origin_monitor.added_monitors.lock().unwrap();
                        assert_eq!(added_monitors.len(), 1);
                        added_monitors.clear();
                }

                let events = origin_node.get_and_clear_pending_events();
                assert_eq!(events.len(), 1);
                match events[0] {
                        Event::PaymentSent { payment_preimage } => {
                                assert_eq!(payment_preimage, our_payment_preimage);
                        },
                        _ => panic!("Unexpected event"),
                }
        }

        fn route_payment(origin_node: &ChannelManager, origin_monitor: &test_utils::TestChannelMonitor, origin_router: &Router, expected_route: &[(&ChannelManager, &test_utils::TestChannelMonitor)], recv_value: u64) -> ([u8; 32], [u8; 32]) {
                let route = origin_router.get_route(&expected_route.last().unwrap().0.get_our_node_id(), &Vec::new(), recv_value, 142).unwrap();
                assert_eq!(route.hops.len(), expected_route.len());
                for (&(node, _), hop) in expected_route.iter().zip(route.hops.iter()) {
                        assert_eq!(hop.pubkey, node.get_our_node_id());
                }

                send_along_route(origin_node, origin_monitor, route, expected_route, recv_value)
        }

        fn route_over_limit(origin_node: &ChannelManager, origin_router: &Router, expected_route: &[&ChannelManager], recv_value: u64) {
                let route = origin_router.get_route(&expected_route.last().unwrap().get_our_node_id(), &Vec::new(), recv_value, 142).unwrap();
                assert_eq!(route.hops.len(), expected_route.len());
                for (node, hop) in expected_route.iter().zip(route.hops.iter()) {
                        assert_eq!(hop.pubkey, node.get_our_node_id());
                }

                let our_payment_preimage = unsafe { [PAYMENT_COUNT; 32] };
                unsafe { PAYMENT_COUNT += 1 };
                let our_payment_hash = {
                        let mut sha = Sha256::new();
                        sha.input(&our_payment_preimage[..]);
                        let mut ret = [0; 32];
                        sha.result(&mut ret);
                        ret
                };

                let err = origin_node.send_payment(route, our_payment_hash).err().unwrap();
                assert_eq!(err.err, "Cannot send value that would put us over our max HTLC value in flight");
        }

        fn send_payment(origin_node: &ChannelManager, origin_monitor: &test_utils::TestChannelMonitor, origin_router: &Router, expected_route: &[(&ChannelManager, &test_utils::TestChannelMonitor)], recv_value: u64) {
                let our_payment_preimage = route_payment(origin_node, origin_monitor, origin_router, expected_route, recv_value).0;
                claim_payment(origin_node, origin_monitor, expected_route, our_payment_preimage);
        }

        fn send_failed_payment(origin_node: &ChannelManager, origin_monitor: &test_utils::TestChannelMonitor, origin_router: &Router, expected_route: &[(&ChannelManager, &test_utils::TestChannelMonitor)]) {
                let route = origin_router.get_route(&expected_route.last().unwrap().0.get_our_node_id(), &Vec::new(), 1000000, 142).unwrap();
                assert_eq!(route.hops.len(), expected_route.len());
                for (&(node, _), hop) in expected_route.iter().zip(route.hops.iter()) {
                        assert_eq!(hop.pubkey, node.get_our_node_id());
                }
                let our_payment_hash = send_along_route(origin_node, origin_monitor, route, expected_route, 1000000).1;

                assert!(expected_route.last().unwrap().0.fail_htlc_backwards(&our_payment_hash));

                let mut expected_next_node = expected_route.last().unwrap().0.get_our_node_id();
                let mut prev_node = expected_route.last().unwrap().0;
                let mut next_msg = None;
                for &(node, _) in expected_route.iter().rev() {
                        assert_eq!(expected_next_node, node.get_our_node_id());
                        match next_msg {
                                Some(msg) => {
                                        node.handle_update_fail_htlc(&prev_node.get_our_node_id(), &msg).unwrap();
                                }, None => {}
                        }

                        let events = node.get_and_clear_pending_events();
                        assert_eq!(events.len(), 1);
                        match events[0] {
                                Event::SendFailHTLC { ref node_id, ref msg } => {
                                        expected_next_node = node_id.clone();
                                        next_msg = Some(msg.clone());
                                },
                                _ => panic!("Unexpected event"),
                        };

                        prev_node = node;
                }

                assert_eq!(expected_next_node, origin_node.get_our_node_id());
                origin_node.handle_update_fail_htlc(&expected_route.first().unwrap().0.get_our_node_id(), &next_msg.unwrap()).unwrap();

                let events = origin_node.get_and_clear_pending_events();
                assert_eq!(events.len(), 1);
                match events[0] {
                        Event::PaymentFailed { payment_hash } => {
                                assert_eq!(payment_hash, our_payment_hash);
                        },
                        _ => panic!("Unexpected event"),
                }
        }

        #[test]
        fn fake_network_test() {
                // Simple test which builds a network of ChannelManagers, connects them to each other, and
                // tests that payments get routed and transactions broadcast in semi-reasonable ways.
                let mut rng = thread_rng();
                let secp_ctx = Secp256k1::new();

                let feeest_1 = Arc::new(test_utils::TestFeeEstimator { sat_per_vbyte: 1 });
                let chain_monitor_1 = Arc::new(chaininterface::ChainWatchInterfaceUtil::new());
                let tx_broadcaster_1 = Arc::new(test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new())});
                let chan_monitor_1 = Arc::new(test_utils::TestChannelMonitor::new(chain_monitor_1.clone(), tx_broadcaster_1.clone()));
                let node_id_1 = {
                        let mut key_slice = [0; 32];
                        rng.fill_bytes(&mut key_slice);
                        SecretKey::from_slice(&secp_ctx, &key_slice).unwrap()
                };
                let node_1 = ChannelManager::new(node_id_1.clone(), 0, true, Network::Testnet, feeest_1.clone(), chan_monitor_1.clone(), chain_monitor_1.clone(), tx_broadcaster_1.clone()).unwrap();
                let router_1 = Router::new(PublicKey::from_secret_key(&secp_ctx, &node_id_1).unwrap());

                let feeest_2 = Arc::new(test_utils::TestFeeEstimator { sat_per_vbyte: 1 });
                let chain_monitor_2 = Arc::new(chaininterface::ChainWatchInterfaceUtil::new());
                let tx_broadcaster_2 = Arc::new(test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new())});
                let chan_monitor_2 = Arc::new(test_utils::TestChannelMonitor::new(chain_monitor_2.clone(), tx_broadcaster_2.clone()));
                let node_id_2 = {
                        let mut key_slice = [0; 32];
                        rng.fill_bytes(&mut key_slice);
                        SecretKey::from_slice(&secp_ctx, &key_slice).unwrap()
                };
                let node_2 = ChannelManager::new(node_id_2.clone(), 0, true, Network::Testnet, feeest_2.clone(), chan_monitor_2.clone(), chain_monitor_2.clone(), tx_broadcaster_2.clone()).unwrap();
                let router_2 = Router::new(PublicKey::from_secret_key(&secp_ctx, &node_id_2).unwrap());

                let feeest_3 = Arc::new(test_utils::TestFeeEstimator { sat_per_vbyte: 1 });
                let chain_monitor_3 = Arc::new(chaininterface::ChainWatchInterfaceUtil::new());
                let tx_broadcaster_3 = Arc::new(test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new())});
                let chan_monitor_3 = Arc::new(test_utils::TestChannelMonitor::new(chain_monitor_3.clone(), tx_broadcaster_3.clone()));
                let node_id_3 = {
                        let mut key_slice = [0; 32];
                        rng.fill_bytes(&mut key_slice);
                        SecretKey::from_slice(&secp_ctx, &key_slice).unwrap()
                };
                let node_3 = ChannelManager::new(node_id_3.clone(), 0, true, Network::Testnet, feeest_3.clone(), chan_monitor_3.clone(), chain_monitor_3.clone(), tx_broadcaster_3.clone()).unwrap();
                let router_3 = Router::new(PublicKey::from_secret_key(&secp_ctx, &node_id_3).unwrap());

                let feeest_4 = Arc::new(test_utils::TestFeeEstimator { sat_per_vbyte: 1 });
                let chain_monitor_4 = Arc::new(chaininterface::ChainWatchInterfaceUtil::new());
                let tx_broadcaster_4 = Arc::new(test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new())});
                let chan_monitor_4 = Arc::new(test_utils::TestChannelMonitor::new(chain_monitor_4.clone(), tx_broadcaster_4.clone()));
                let node_id_4 = {
                        let mut key_slice = [0; 32];
                        rng.fill_bytes(&mut key_slice);
                        SecretKey::from_slice(&secp_ctx, &key_slice).unwrap()
                };
                let node_4 = ChannelManager::new(node_id_4.clone(), 0, true, Network::Testnet, feeest_4.clone(), chan_monitor_4.clone(), chain_monitor_4.clone(), tx_broadcaster_4.clone()).unwrap();
                let router_4 = Router::new(PublicKey::from_secret_key(&secp_ctx, &node_id_4).unwrap());

                // Create some initial channels
                let chan_announcement_1 = create_chan_between_nodes(&node_1, &chain_monitor_1, &chan_monitor_1, &node_2, &chain_monitor_2, &chan_monitor_2);
                for router in vec!(&router_1, &router_2, &router_3, &router_4) {
                        assert!(router.handle_channel_announcement(&chan_announcement_1.0).unwrap());
                        router.handle_channel_update(&chan_announcement_1.1).unwrap();
                        router.handle_channel_update(&chan_announcement_1.2).unwrap();
                }
                let chan_announcement_2 = create_chan_between_nodes(&node_2, &chain_monitor_2, &chan_monitor_2, &node_3, &chain_monitor_3, &chan_monitor_3);
                for router in vec!(&router_1, &router_2, &router_3, &router_4) {
                        assert!(router.handle_channel_announcement(&chan_announcement_2.0).unwrap());
                        router.handle_channel_update(&chan_announcement_2.1).unwrap();
                        router.handle_channel_update(&chan_announcement_2.2).unwrap();
                }
                let chan_announcement_3 = create_chan_between_nodes(&node_3, &chain_monitor_3, &chan_monitor_3, &node_4, &chain_monitor_4, &chan_monitor_4);
                for router in vec!(&router_1, &router_2, &router_3, &router_4) {
                        assert!(router.handle_channel_announcement(&chan_announcement_3.0).unwrap());
                        router.handle_channel_update(&chan_announcement_3.1).unwrap();
                        router.handle_channel_update(&chan_announcement_3.2).unwrap();
                }

                // Rebalance the network a bit by relaying one payment through all the channels...
                send_payment(&node_1, &chan_monitor_1, &router_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_3, &*chan_monitor_3), (&*node_4, &*chan_monitor_4))[..], 8000000);
                send_payment(&node_1, &chan_monitor_1, &router_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_3, &*chan_monitor_3), (&*node_4, &*chan_monitor_4))[..], 8000000);
                send_payment(&node_1, &chan_monitor_1, &router_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_3, &*chan_monitor_3), (&*node_4, &*chan_monitor_4))[..], 8000000);
                send_payment(&node_1, &chan_monitor_1, &router_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_3, &*chan_monitor_3), (&*node_4, &*chan_monitor_4))[..], 8000000);
                send_payment(&node_1, &chan_monitor_1, &router_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_3, &*chan_monitor_3), (&*node_4, &*chan_monitor_4))[..], 8000000);

                // Send some more payments
                send_payment(&node_2, &chan_monitor_2, &router_2, &vec!((&*node_3, &*chan_monitor_3), (&*node_4, &*chan_monitor_4))[..], 1000000);
                send_payment(&node_4, &chan_monitor_4, &router_4, &vec!((&*node_3, &*chan_monitor_3), (&*node_2, &*chan_monitor_2), (&*node_1, &*chan_monitor_1))[..], 1000000);
                send_payment(&node_4, &chan_monitor_4, &router_4, &vec!((&*node_3, &*chan_monitor_3), (&*node_2, &*chan_monitor_2))[..], 1000000);

                // Test failure packets
                send_failed_payment(&node_1, &chan_monitor_1, &router_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_3, &*chan_monitor_3), (&*node_4, &*chan_monitor_4))[..]);

                // Add a new channel that skips 3
                let chan_announcement_4 = create_chan_between_nodes(&node_2, &chain_monitor_2, &chan_monitor_2, &node_4, &chain_monitor_4, &chan_monitor_4);
                for router in vec!(&router_1, &router_2, &router_3, &router_4) {
                        assert!(router.handle_channel_announcement(&chan_announcement_4.0).unwrap());
                        router.handle_channel_update(&chan_announcement_4.1).unwrap();
                        router.handle_channel_update(&chan_announcement_4.2).unwrap();
                }

                send_payment(&node_1, &chan_monitor_1, &router_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_4, &*chan_monitor_4))[..], 1000000);
                send_payment(&node_3, &chan_monitor_3, &router_3, &vec!((&*node_4, &*chan_monitor_4))[..], 1000000);
                send_payment(&node_2, &chan_monitor_2, &router_2, &vec!((&*node_4, &*chan_monitor_4))[..], 8000000);
                send_payment(&node_2, &chan_monitor_2, &router_2, &vec!((&*node_4, &*chan_monitor_4))[..], 8000000);
                send_payment(&node_2, &chan_monitor_2, &router_2, &vec!((&*node_4, &*chan_monitor_4))[..], 8000000);
                send_payment(&node_2, &chan_monitor_2, &router_2, &vec!((&*node_4, &*chan_monitor_4))[..], 8000000);
                send_payment(&node_2, &chan_monitor_2, &router_2, &vec!((&*node_4, &*chan_monitor_4))[..], 8000000);

                // Do some rebalance loop payments, simultaneously
                let mut hops = Vec::with_capacity(3);
                hops.push(RouteHop {
                        pubkey: node_3.get_our_node_id(),
                        short_channel_id: chan_announcement_2.1.contents.short_channel_id,
                        fee_msat: 0,
                        cltv_expiry_delta: chan_announcement_3.1.contents.cltv_expiry_delta as u32
                });
                hops.push(RouteHop {
                        pubkey: node_4.get_our_node_id(),
                        short_channel_id: chan_announcement_3.1.contents.short_channel_id,
                        fee_msat: 0,
                        cltv_expiry_delta: chan_announcement_4.2.contents.cltv_expiry_delta as u32
                });
                hops.push(RouteHop {
                        pubkey: node_2.get_our_node_id(),
                        short_channel_id: chan_announcement_4.1.contents.short_channel_id,
                        fee_msat: 1000000,
                        cltv_expiry_delta: 142,
                });
                hops[1].fee_msat = chan_announcement_4.2.contents.fee_base_msat as u64 + chan_announcement_4.2.contents.fee_proportional_millionths as u64 * hops[2].fee_msat as u64 / 1000000;
                hops[0].fee_msat = chan_announcement_3.1.contents.fee_base_msat as u64 + chan_announcement_3.1.contents.fee_proportional_millionths as u64 * hops[1].fee_msat as u64 / 1000000;
                let payment_preimage_1 = send_along_route(&node_2, &chan_monitor_2, Route { hops }, &vec!((&*node_3, &*chan_monitor_3), (&*node_4, &*chan_monitor_4), (&*node_2, &*chan_monitor_2))[..], 1000000).0;

                let mut hops = Vec::with_capacity(3);
                hops.push(RouteHop {
                        pubkey: node_4.get_our_node_id(),
                        short_channel_id: chan_announcement_4.1.contents.short_channel_id,
                        fee_msat: 0,
                        cltv_expiry_delta: chan_announcement_3.2.contents.cltv_expiry_delta as u32
                });
                hops.push(RouteHop {
                        pubkey: node_3.get_our_node_id(),
                        short_channel_id: chan_announcement_3.1.contents.short_channel_id,
                        fee_msat: 0,
                        cltv_expiry_delta: chan_announcement_2.2.contents.cltv_expiry_delta as u32
                });
                hops.push(RouteHop {
                        pubkey: node_2.get_our_node_id(),
                        short_channel_id: chan_announcement_2.1.contents.short_channel_id,
                        fee_msat: 1000000,
                        cltv_expiry_delta: 142,
                });
                hops[1].fee_msat = chan_announcement_2.2.contents.fee_base_msat as u64 + chan_announcement_2.2.contents.fee_proportional_millionths as u64 * hops[2].fee_msat as u64 / 1000000;
                hops[0].fee_msat = chan_announcement_3.2.contents.fee_base_msat as u64 + chan_announcement_3.2.contents.fee_proportional_millionths as u64 * hops[1].fee_msat as u64 / 1000000;
                let payment_preimage_2 = send_along_route(&node_2, &chan_monitor_2, Route { hops }, &vec!((&*node_4, &*chan_monitor_4), (&*node_3, &*chan_monitor_3), (&*node_2, &*chan_monitor_2))[..], 1000000).0;

                // Claim the rebalances...
                claim_payment(&node_2, &chan_monitor_2, &vec!((&*node_4, &*chan_monitor_4), (&*node_3, &*chan_monitor_3), (&*node_2, &*chan_monitor_2))[..], payment_preimage_2);
                claim_payment(&node_2, &chan_monitor_2, &vec!((&*node_3, &*chan_monitor_3), (&*node_4, &*chan_monitor_4), (&*node_2, &*chan_monitor_2))[..], payment_preimage_1);

                // Add a duplicate new channel from 2 to 4
                let chan_announcement_5 = create_chan_between_nodes(&node_2, &chain_monitor_2, &chan_monitor_2, &node_4, &chain_monitor_4, &chan_monitor_4);
                for router in vec!(&router_1, &router_2, &router_3, &router_4) {
                        assert!(router.handle_channel_announcement(&chan_announcement_5.0).unwrap());
                        router.handle_channel_update(&chan_announcement_5.1).unwrap();
                        router.handle_channel_update(&chan_announcement_5.2).unwrap();
                }

                // Send some payments across both channels
                let payment_preimage_3 = route_payment(&node_1, &chan_monitor_1, &router_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_4, &*chan_monitor_4))[..], 3000000).0;
                let payment_preimage_4 = route_payment(&node_1, &chan_monitor_1, &router_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_4, &*chan_monitor_4))[..], 3000000).0;
                let payment_preimage_5 = route_payment(&node_1, &chan_monitor_1, &router_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_4, &*chan_monitor_4))[..], 3000000).0;

                route_over_limit(&node_1, &router_1, &vec!(&*node_2, &*node_4)[..], 3000000);

                //TODO: Test that routes work again here as we've been notified that the channel is full

                claim_payment(&node_1, &chan_monitor_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_4, &*chan_monitor_4))[..], payment_preimage_3);
                claim_payment(&node_1, &chan_monitor_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_4, &*chan_monitor_4))[..], payment_preimage_4);
                claim_payment(&node_1, &chan_monitor_1, &vec!((&*node_2, &*chan_monitor_2), (&*node_4, &*chan_monitor_4))[..], payment_preimage_5);

                // Close down the channels...
                close_channel(&node_1, &tx_broadcaster_1, &node_2, &tx_broadcaster_2, &chan_announcement_1.3, true);
                close_channel(&node_2, &tx_broadcaster_2, &node_3, &tx_broadcaster_3, &chan_announcement_2.3, false);
                close_channel(&node_3, &tx_broadcaster_3, &node_4, &tx_broadcaster_4, &chan_announcement_3.3, true);
                close_channel(&node_2, &tx_broadcaster_2, &node_4, &tx_broadcaster_4, &chan_announcement_4.3, false);

                // Check that we processed all pending events
                for node in vec!(&node_1, &node_2, &node_3, &node_4) {
                        assert_eq!(node.get_and_clear_pending_events().len(), 0);
                }
                for chan_monitor in vec!(&chan_monitor_1, &chan_monitor_2, &chan_monitor_3, &chan_monitor_4) {
                        assert_eq!(chan_monitor.added_monitors.lock().unwrap().len(), 0);
                }
        }
}