Consider channels "live" even if they are awaiting a monitor update
[rust-lightning] / lightning / src / ln / channel.rs
index d9c7fc5ad27b049d24dbe55882c3a21a0fc983ca..2672511115ef6fd9ae159e1572fa5e953d9a1308 100644 (file)
@@ -7,7 +7,6 @@
 // You may not use this file except in accordance with one or both of these
 // licenses.
 
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::script::{Script,Builder};
 use bitcoin::blockdata::transaction::{TxIn, TxOut, Transaction, SigHashType};
 use bitcoin::blockdata::opcodes;
@@ -16,16 +15,18 @@ use bitcoin::consensus::encode;
 
 use bitcoin::hashes::Hash;
 use bitcoin::hashes::sha256::Hash as Sha256;
+use bitcoin::hashes::sha256d::Hash as Sha256d;
 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
 
 use bitcoin::secp256k1::key::{PublicKey,SecretKey};
 use bitcoin::secp256k1::{Secp256k1,Signature};
 use bitcoin::secp256k1;
 
+use ln::{PaymentPreimage, PaymentHash};
 use ln::features::{ChannelFeatures, InitFeatures};
 use ln::msgs;
 use ln::msgs::{DecodeError, OptionalField, DataLossProtect};
-use ln::channelmanager::{PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingHTLCInfo, RAACommitmentOrder, PaymentPreimage, PaymentHash, BREAKDOWN_TIMEOUT, MAX_LOCAL_BREAKDOWN_TIMEOUT};
+use ln::channelmanager::{BestBlock, PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingHTLCInfo, RAACommitmentOrder, BREAKDOWN_TIMEOUT, MIN_CLTV_EXPIRY_DELTA, MAX_LOCAL_BREAKDOWN_TIMEOUT};
 use ln::chan_utils::{CounterpartyCommitmentSecrets, TxCreationKeys, HTLCOutputInCommitment, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT, make_funding_redeemscript, ChannelPublicKeys, CommitmentTransaction, HolderCommitmentTransaction, ChannelTransactionParameters, CounterpartyChannelTransactionParameters, MAX_HTLCS, get_commitment_transaction_number_obscure_factor};
 use ln::chan_utils;
 use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
@@ -37,11 +38,11 @@ use util::ser::{Readable, ReadableArgs, Writeable, Writer, VecWriter};
 use util::logger::Logger;
 use util::errors::APIError;
 use util::config::{UserConfig,ChannelConfig};
+use util::scid_utils::scid_from_parts;
 
-use std;
-use std::default::Default;
-use std::{cmp,mem,fmt};
-use std::ops::Deref;
+use prelude::*;
+use core::{cmp,mem,fmt};
+use core::ops::Deref;
 #[cfg(any(test, feature = "fuzztarget"))]
 use std::sync::Mutex;
 use bitcoin::hashes::hex::ToHex;
@@ -96,6 +97,7 @@ enum InboundHTLCState {
        /// is used to derive commitment keys, which are used to construct the
        /// signatures in a commitment_signed message.
        /// Implies AwaitingRemoteRevoke.
+       ///
        /// [BOLT #2]: https://github.com/lightningnetwork/lightning-rfc/blob/master/02-peer-protocol.md
        AwaitingRemoteRevokeToAnnounce(PendingHTLCStatus),
        /// Included in a received commitment_signed message (implying we've revoke_and_ack'd it).
@@ -247,18 +249,21 @@ const MULTI_STATE_FLAGS: u32 = BOTH_SIDES_SHUTDOWN_MASK | ChannelState::PeerDisc
 
 pub const INITIAL_COMMITMENT_NUMBER: u64 = (1 << 48) - 1;
 
-/// Liveness is called to fluctuate given peer disconnecton/monitor failures/closing.
-/// If channel is public, network should have a liveness view announced by us on a
-/// best-effort, which means we may filter out some status transitions to avoid spam.
-/// See further timer_chan_freshness_every_min.
-#[derive(PartialEq)]
-enum UpdateStatus {
-       /// Status has been gossiped.
-       Fresh,
-       /// Status has been changed.
-       DisabledMarked,
-       /// Status has been marked to be gossiped at next flush
+/// The "channel disabled" bit in channel_update must be set based on whether we are connected to
+/// our counterparty or not. However, we don't want to announce updates right away to avoid
+/// spamming the network with updates if the connection is flapping. Instead, we "stage" updates to
+/// our channel_update message and track the current state here.
+/// See implementation at [`super::channelmanager::ChannelManager::timer_tick_occurred`].
+#[derive(Clone, Copy, PartialEq)]
+pub(super) enum ChannelUpdateStatus {
+       /// We've announced the channel as enabled and are connected to our peer.
+       Enabled,
+       /// Our channel is no longer live, but we haven't announced the channel as disabled yet.
        DisabledStaged,
+       /// Our channel is live again, but we haven't announced the channel as enabled yet.
+       EnabledStaged,
+       /// We've announced the channel as disabled.
+       Disabled,
 }
 
 /// An enum indicating whether the local or remote side offered a given HTLC.
@@ -282,6 +287,19 @@ impl HTLCCandidate {
        }
 }
 
+/// Information needed for constructing an invoice route hint for this channel.
+#[derive(Clone)]
+pub struct CounterpartyForwardingInfo {
+       /// Base routing fee in millisatoshis.
+       pub fee_base_msat: u32,
+       /// Amount in millionths of a satoshi the channel will charge per transferred satoshi.
+       pub fee_proportional_millionths: u32,
+       /// The minimum difference in cltv_expiry between an ingoing HTLC and its outgoing counterpart,
+       /// such that the outgoing HTLC is forwardable to this counterparty. See `msgs::ChannelUpdate`'s
+       /// `cltv_expiry_delta` for more details.
+       pub cltv_expiry_delta: u16,
+}
+
 // TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
 // has been completed, and then turn into a Channel to get compiler-time enforcement of things like
 // calling channel_id() before we're set up or things like get_outbound_funding_signed on an
@@ -362,16 +380,10 @@ pub(super) struct Channel<Signer: Sign> {
 
        last_sent_closing_fee: Option<(u32, u64, Signature)>, // (feerate, fee, holder_sig)
 
-       /// The hash of the block in which the funding transaction reached our CONF_TARGET. We use this
-       /// to detect unconfirmation after a serialize-unserialize roundtrip where we may not see a full
-       /// series of block_connected/block_disconnected calls. Obviously this is not a guarantee as we
-       /// could miss the funding_tx_confirmed_in block as well, but it serves as a useful fallback.
+       /// The hash of the block in which the funding transaction was included.
        funding_tx_confirmed_in: Option<BlockHash>,
+       funding_tx_confirmation_height: u32,
        short_channel_id: Option<u64>,
-       /// Used to deduplicate block_connected callbacks, also used to verify consistency during
-       /// ChannelManager deserialization (hence pub(super))
-       pub(super) last_block_connected: BlockHash,
-       funding_tx_confirmations: u64,
 
        counterparty_dust_limit_satoshis: u64,
        #[cfg(test)]
@@ -395,10 +407,12 @@ pub(super) struct Channel<Signer: Sign> {
        //implied by OUR_MAX_HTLCS: max_accepted_htlcs: u16,
        minimum_depth: u32,
 
+       counterparty_forwarding_info: Option<CounterpartyForwardingInfo>,
+
        pub(crate) channel_transaction_parameters: ChannelTransactionParameters,
+       funding_transaction: Option<Transaction>,
 
        counterparty_cur_commitment_point: Option<PublicKey>,
-
        counterparty_prev_commitment_point: Option<PublicKey>,
        counterparty_node_id: PublicKey,
 
@@ -406,7 +420,11 @@ pub(super) struct Channel<Signer: Sign> {
 
        commitment_secrets: CounterpartyCommitmentSecrets,
 
-       network_sync: UpdateStatus,
+       channel_update_status: ChannelUpdateStatus,
+
+       /// Our counterparty's channel_announcement signatures provided in announcement_signatures.
+       /// This can be used to rebroadcast the channel_announcement message later.
+       announcement_sigs: Option<(Signature, Signature)>,
 
        // We save these values so we can make sure `next_local_commit_tx_fee_msat` and
        // `next_remote_commit_tx_fee_msat` properly predict what the next commitment transaction fee will
@@ -428,12 +446,7 @@ struct CommitmentTxInfoCached {
 }
 
 pub const OUR_MAX_HTLCS: u16 = 50; //TODO
-/// Confirmation count threshold at which we close a channel. Ideally we'd keep the channel around
-/// on ice until the funding transaction gets more confirmations, but the LN protocol doesn't
-/// really allow for this, so instead we're stuck closing it out at that point.
-const UNCONF_THRESHOLD: u32 = 6;
 const SPENDING_INPUT_FOR_A_OUTPUT_WEIGHT: u64 = 79; // prevout: 36, nSequence: 4, script len: 1, witness lengths: (3+1)/4, sig: 73/4, if-selector: 1, redeemScript: (6 ops + 2*33 pubkeys + 1*2 delay)/4
-const B_OUTPUT_PLUS_SPENDING_INPUT_WEIGHT: u64 = 104; // prevout: 40, nSequence: 4, script len: 1, witness lengths: 3/4, sig: 73/4, pubkey: 33/4, output: 31 (TODO: Wrong? Useless?)
 
 #[cfg(not(test))]
 const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
@@ -448,6 +461,22 @@ pub const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
 /// it's 2^24.
 pub const MAX_FUNDING_SATOSHIS: u64 = 1 << 24;
 
+/// Maximum counterparty `dust_limit_satoshis` allowed. 2 * standard dust threshold on p2wsh output
+/// Scales up on Bitcoin Core's proceeding policy with dust outputs. A typical p2wsh output is 43
+/// bytes to which Core's `GetDustThreshold()` sums up a minimal spend of 67 bytes (even if
+/// a p2wsh witnessScript might be *effectively* smaller), `dustRelayFee` is set to 3000sat/kb, thus
+/// 110 * 3000 / 1000 = 330. Per-protocol rules, all time-sensitive outputs are p2wsh, a value of
+/// 330 sats is the lower bound desired to ensure good propagation of transactions. We give a bit
+/// of margin to our counterparty and pick up 660 satoshis as an accepted `dust_limit_satoshis`
+/// upper bound to avoid negotiation conflicts with other implementations.
+pub const MAX_DUST_LIMIT_SATOSHIS: u64 = 2 * 330;
+
+/// A typical p2wsh output is 43 bytes to which Core's `GetDustThreshold()` sums up a minimal
+/// spend of 67 bytes (even if a p2wsh witnessScript might be *effectively* smaller), `dustRelayFee`
+/// is set to 3000sat/kb, thus 110 * 3000 / 1000 = 330. Per-protocol rules, all time-sensitive outputs
+/// are p2wsh, a value of 330 sats is the lower bound desired to ensure good propagation of transactions.
+pub const MIN_DUST_LIMIT_SATOSHIS: u64 = 330;
+
 /// Used to return a simple Error back to ChannelManager. Will get converted to a
 /// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our
 /// channel_id in ChannelManager.
@@ -491,10 +520,6 @@ impl<Signer: Sign> Channel<Signer> {
                cmp::min(channel_value_satoshis, cmp::max(q, 1000)) //TODO
        }
 
-       fn derive_holder_dust_limit_satoshis(at_open_background_feerate: u32) -> u64 {
-               cmp::max(at_open_background_feerate as u64 * B_OUTPUT_PLUS_SPENDING_INPUT_WEIGHT / 1000, 546) //TODO
-       }
-
        // Constructors:
        pub fn new_outbound<K: Deref, F: Deref>(fee_estimator: &F, keys_provider: &K, counterparty_node_id: PublicKey, channel_value_satoshis: u64, push_msat: u64, user_id: u64, config: &UserConfig) -> Result<Channel<Signer>, APIError>
        where K::Target: KeysInterface<Signer = Signer>,
@@ -514,9 +539,9 @@ impl<Signer: Sign> Channel<Signer> {
                if holder_selected_contest_delay < BREAKDOWN_TIMEOUT {
                        return Err(APIError::APIMisuseError {err: format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks", holder_selected_contest_delay)});
                }
-               let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
-               if Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(channel_value_satoshis) < Channel::<Signer>::derive_holder_dust_limit_satoshis(background_feerate) {
-                       return Err(APIError::FeeRateTooHigh{err: format!("Not enough reserve above dust limit can be found at current fee rate({})", background_feerate), feerate: background_feerate});
+               let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(channel_value_satoshis);
+               if holder_selected_channel_reserve_satoshis < MIN_DUST_LIMIT_SATOSHIS {
+                       return Err(APIError::APIMisuseError { err: format!("Holder selected channel  reserve below implemention limit dust_limit_satoshis {}", holder_selected_channel_reserve_satoshis) });
                }
 
                let feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
@@ -568,13 +593,12 @@ impl<Signer: Sign> Channel<Signer> {
                        last_sent_closing_fee: None,
 
                        funding_tx_confirmed_in: None,
+                       funding_tx_confirmation_height: 0,
                        short_channel_id: None,
-                       last_block_connected: Default::default(),
-                       funding_tx_confirmations: 0,
 
                        feerate_per_kw: feerate,
                        counterparty_dust_limit_satoshis: 0,
-                       holder_dust_limit_satoshis: Channel::<Signer>::derive_holder_dust_limit_satoshis(background_feerate),
+                       holder_dust_limit_satoshis: MIN_DUST_LIMIT_SATOSHIS,
                        counterparty_max_htlc_value_in_flight_msat: 0,
                        counterparty_selected_channel_reserve_satoshis: 0,
                        counterparty_htlc_minimum_msat: 0,
@@ -582,6 +606,8 @@ impl<Signer: Sign> Channel<Signer> {
                        counterparty_max_accepted_htlcs: 0,
                        minimum_depth: 0, // Filled in in accept_channel
 
+                       counterparty_forwarding_info: None,
+
                        channel_transaction_parameters: ChannelTransactionParameters {
                                holder_pubkeys: pubkeys,
                                holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
@@ -589,8 +615,9 @@ impl<Signer: Sign> Channel<Signer> {
                                counterparty_parameters: None,
                                funding_outpoint: None
                        },
-                       counterparty_cur_commitment_point: None,
+                       funding_transaction: None,
 
+                       counterparty_cur_commitment_point: None,
                        counterparty_prev_commitment_point: None,
                        counterparty_node_id,
 
@@ -598,7 +625,9 @@ impl<Signer: Sign> Channel<Signer> {
 
                        commitment_secrets: CounterpartyCommitmentSecrets::new(),
 
-                       network_sync: UpdateStatus::Fresh,
+                       channel_update_status: ChannelUpdateStatus::Enabled,
+
+                       announcement_sigs: None,
 
                        #[cfg(any(test, feature = "fuzztarget"))]
                        next_local_commitment_tx_fee_info_cached: Mutex::new(None),
@@ -692,11 +721,11 @@ impl<Signer: Sign> Channel<Signer> {
                if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
                        return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, config.peer_channel_config_limits.min_max_accepted_htlcs)));
                }
-               if msg.dust_limit_satoshis < config.peer_channel_config_limits.min_dust_limit_satoshis {
-                       return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the user specified limit ({})", msg.dust_limit_satoshis, config.peer_channel_config_limits.min_dust_limit_satoshis)));
+               if msg.dust_limit_satoshis < MIN_DUST_LIMIT_SATOSHIS {
+                       return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
                }
-               if msg.dust_limit_satoshis > config.peer_channel_config_limits.max_dust_limit_satoshis {
-                       return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the user specified limit ({})", msg.dust_limit_satoshis, config.peer_channel_config_limits.max_dust_limit_satoshis)));
+               if msg.dust_limit_satoshis >  MAX_DUST_LIMIT_SATOSHIS {
+                       return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_DUST_LIMIT_SATOSHIS)));
                }
 
                // Convert things into internal flags and prep our state:
@@ -712,13 +741,12 @@ impl<Signer: Sign> Channel<Signer> {
 
                let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
 
-               let holder_dust_limit_satoshis = Channel::<Signer>::derive_holder_dust_limit_satoshis(background_feerate);
                let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(msg.funding_satoshis);
-               if holder_selected_channel_reserve_satoshis < holder_dust_limit_satoshis {
-                       return Err(ChannelError::Close(format!("Suitable channel reserve not found. remote_channel_reserve was ({}). dust_limit_satoshis is ({}).", holder_selected_channel_reserve_satoshis, holder_dust_limit_satoshis)));
+               if holder_selected_channel_reserve_satoshis < MIN_DUST_LIMIT_SATOSHIS {
+                       return Err(ChannelError::Close(format!("Suitable channel reserve not found. remote_channel_reserve was ({}). dust_limit_satoshis is ({}).", holder_selected_channel_reserve_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
                }
-               if msg.channel_reserve_satoshis < holder_dust_limit_satoshis {
-                       return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is smaller than our dust limit ({})", msg.channel_reserve_satoshis, holder_dust_limit_satoshis)));
+               if msg.channel_reserve_satoshis < MIN_DUST_LIMIT_SATOSHIS {
+                       return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is smaller than our dust limit ({})", msg.channel_reserve_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
                }
                if holder_selected_channel_reserve_satoshis < msg.dust_limit_satoshis {
                        return Err(ChannelError::Close(format!("Dust limit ({}) too high for the channel reserve we require the remote to keep ({})", msg.dust_limit_satoshis, holder_selected_channel_reserve_satoshis)));
@@ -804,14 +832,13 @@ impl<Signer: Sign> Channel<Signer> {
                        last_sent_closing_fee: None,
 
                        funding_tx_confirmed_in: None,
+                       funding_tx_confirmation_height: 0,
                        short_channel_id: None,
-                       last_block_connected: Default::default(),
-                       funding_tx_confirmations: 0,
 
                        feerate_per_kw: msg.feerate_per_kw,
                        channel_value_satoshis: msg.funding_satoshis,
                        counterparty_dust_limit_satoshis: msg.dust_limit_satoshis,
-                       holder_dust_limit_satoshis,
+                       holder_dust_limit_satoshis: MIN_DUST_LIMIT_SATOSHIS,
                        counterparty_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
                        counterparty_selected_channel_reserve_satoshis: msg.channel_reserve_satoshis,
                        counterparty_htlc_minimum_msat: msg.htlc_minimum_msat,
@@ -819,6 +846,8 @@ impl<Signer: Sign> Channel<Signer> {
                        counterparty_max_accepted_htlcs: msg.max_accepted_htlcs,
                        minimum_depth: config.own_channel_config.minimum_depth,
 
+                       counterparty_forwarding_info: None,
+
                        channel_transaction_parameters: ChannelTransactionParameters {
                                holder_pubkeys: pubkeys,
                                holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
@@ -829,8 +858,9 @@ impl<Signer: Sign> Channel<Signer> {
                                }),
                                funding_outpoint: None
                        },
-                       counterparty_cur_commitment_point: Some(msg.first_per_commitment_point),
+                       funding_transaction: None,
 
+                       counterparty_cur_commitment_point: Some(msg.first_per_commitment_point),
                        counterparty_prev_commitment_point: None,
                        counterparty_node_id,
 
@@ -838,7 +868,9 @@ impl<Signer: Sign> Channel<Signer> {
 
                        commitment_secrets: CounterpartyCommitmentSecrets::new(),
 
-                       network_sync: UpdateStatus::Fresh,
+                       channel_update_status: ChannelUpdateStatus::Enabled,
+
+                       announcement_sigs: None,
 
                        #[cfg(any(test, feature = "fuzztarget"))]
                        next_local_commitment_tx_fee_info_cached: Mutex::new(None),
@@ -1197,7 +1229,7 @@ impl<Signer: Sign> Channel<Signer> {
                // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
                // these, but for now we just have to treat them as normal.
 
-               let mut pending_idx = std::usize::MAX;
+               let mut pending_idx = core::usize::MAX;
                for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
                        if htlc.htlc_id == htlc_id_arg {
                                assert_eq!(htlc.payment_hash, payment_hash_calc);
@@ -1220,7 +1252,7 @@ impl<Signer: Sign> Channel<Signer> {
                                break;
                        }
                }
-               if pending_idx == std::usize::MAX {
+               if pending_idx == core::usize::MAX {
                        return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
                }
 
@@ -1309,7 +1341,7 @@ impl<Signer: Sign> Channel<Signer> {
        ///
        /// Note that it is still possible to hit these assertions in case we find a preimage on-chain
        /// but then have a reorg which settles on an HTLC-failure on chain.
-       pub fn get_update_fail_htlc(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> {
+       pub fn get_update_fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, logger: &L) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> where L::Target: Logger {
                if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
                        panic!("Was asked to fail an HTLC when channel was not in an operational state");
                }
@@ -1319,7 +1351,7 @@ impl<Signer: Sign> Channel<Signer> {
                // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
                // these, but for now we just have to treat them as normal.
 
-               let mut pending_idx = std::usize::MAX;
+               let mut pending_idx = core::usize::MAX;
                for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
                        if htlc.htlc_id == htlc_id_arg {
                                match htlc.state {
@@ -1336,7 +1368,7 @@ impl<Signer: Sign> Channel<Signer> {
                                pending_idx = idx;
                        }
                }
-               if pending_idx == std::usize::MAX {
+               if pending_idx == core::usize::MAX {
                        return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
                }
 
@@ -1359,6 +1391,7 @@ impl<Signer: Sign> Channel<Signer> {
                                        _ => {}
                                }
                        }
+                       log_trace!(logger, "Placing failure for HTLC ID {} in holding cell", htlc_id_arg);
                        self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
                                htlc_id: htlc_id_arg,
                                err_packet,
@@ -1366,6 +1399,7 @@ impl<Signer: Sign> Channel<Signer> {
                        return Ok(None);
                }
 
+               log_trace!(logger, "Failing HTLC ID {} back with a update_fail_htlc message", htlc_id_arg);
                {
                        let htlc = &mut self.pending_inbound_htlcs[pending_idx];
                        htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
@@ -1394,9 +1428,6 @@ impl<Signer: Sign> Channel<Signer> {
                if msg.channel_reserve_satoshis > self.channel_value_satoshis {
                        return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.channel_value_satoshis)));
                }
-               if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
-                       return Err(ChannelError::Close(format!("Bogus channel_reserve ({}) and dust_limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis)));
-               }
                if msg.channel_reserve_satoshis < self.holder_dust_limit_satoshis {
                        return Err(ChannelError::Close(format!("Peer never wants payout outputs? channel_reserve_satoshis was ({}). dust_limit is ({})", msg.channel_reserve_satoshis, self.holder_dust_limit_satoshis)));
                }
@@ -1432,11 +1463,11 @@ impl<Signer: Sign> Channel<Signer> {
                if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
                        return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, config.peer_channel_config_limits.min_max_accepted_htlcs)));
                }
-               if msg.dust_limit_satoshis < config.peer_channel_config_limits.min_dust_limit_satoshis {
-                       return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the user specified limit ({})", msg.dust_limit_satoshis, config.peer_channel_config_limits.min_dust_limit_satoshis)));
+               if msg.dust_limit_satoshis < MIN_DUST_LIMIT_SATOSHIS {
+                       return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
                }
-               if msg.dust_limit_satoshis > config.peer_channel_config_limits.max_dust_limit_satoshis {
-                       return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the user specified limit ({})", msg.dust_limit_satoshis, config.peer_channel_config_limits.max_dust_limit_satoshis)));
+               if msg.dust_limit_satoshis > MAX_DUST_LIMIT_SATOSHIS {
+                       return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_DUST_LIMIT_SATOSHIS)));
                }
                if msg.minimum_depth > config.peer_channel_config_limits.max_minimum_depth {
                        return Err(ChannelError::Close(format!("We consider the minimum depth to be unreasonably large. Expected minimum: ({}). Actual: ({})", config.peer_channel_config_limits.max_minimum_depth, msg.minimum_depth)));
@@ -1522,7 +1553,7 @@ impl<Signer: Sign> Channel<Signer> {
                &self.get_counterparty_pubkeys().funding_pubkey
        }
 
-       pub fn funding_created<L: Deref>(&mut self, msg: &msgs::FundingCreated, logger: &L) -> Result<(msgs::FundingSigned, ChannelMonitor<Signer>), ChannelError> where L::Target: Logger {
+       pub fn funding_created<L: Deref>(&mut self, msg: &msgs::FundingCreated, best_block: BestBlock, logger: &L) -> Result<(msgs::FundingSigned, ChannelMonitor<Signer>), ChannelError> where L::Target: Logger {
                if self.is_outbound() {
                        return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned()));
                }
@@ -1570,13 +1601,13 @@ impl<Signer: Sign> Channel<Signer> {
                let funding_redeemscript = self.get_funding_redeemscript();
                let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
                let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
-               let mut channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
-                                                             &self.shutdown_pubkey, self.get_holder_selected_contest_delay(),
-                                                             &self.destination_script, (funding_txo, funding_txo_script.clone()),
-                                                             &self.channel_transaction_parameters,
-                                                             funding_redeemscript.clone(), self.channel_value_satoshis,
-                                                             obscure_factor,
-                                                             holder_commitment_tx);
+               let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
+                                                         &self.shutdown_pubkey, self.get_holder_selected_contest_delay(),
+                                                         &self.destination_script, (funding_txo, funding_txo_script.clone()),
+                                                         &self.channel_transaction_parameters,
+                                                         funding_redeemscript.clone(), self.channel_value_satoshis,
+                                                         obscure_factor,
+                                                         holder_commitment_tx, best_block);
 
                channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_commitment_txid, Vec::new(), self.cur_counterparty_commitment_transaction_number, self.counterparty_cur_commitment_point.unwrap(), logger);
 
@@ -1593,7 +1624,7 @@ impl<Signer: Sign> Channel<Signer> {
 
        /// Handles a funding_signed message from the remote end.
        /// If this call is successful, broadcast the funding transaction (and not before!)
-       pub fn funding_signed<L: Deref>(&mut self, msg: &msgs::FundingSigned, logger: &L) -> Result<ChannelMonitor<Signer>, ChannelError> where L::Target: Logger {
+       pub fn funding_signed<L: Deref>(&mut self, msg: &msgs::FundingSigned, best_block: BestBlock, logger: &L) -> Result<(ChannelMonitor<Signer>, Transaction), ChannelError> where L::Target: Logger {
                if !self.is_outbound() {
                        return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
                }
@@ -1640,13 +1671,13 @@ impl<Signer: Sign> Channel<Signer> {
                let funding_txo = self.get_funding_txo().unwrap();
                let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
                let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
-               let mut channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
-                                                             &self.shutdown_pubkey, self.get_holder_selected_contest_delay(),
-                                                             &self.destination_script, (funding_txo, funding_txo_script),
-                                                             &self.channel_transaction_parameters,
-                                                             funding_redeemscript.clone(), self.channel_value_satoshis,
-                                                             obscure_factor,
-                                                             holder_commitment_tx);
+               let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
+                                                         &self.shutdown_pubkey, self.get_holder_selected_contest_delay(),
+                                                         &self.destination_script, (funding_txo, funding_txo_script),
+                                                         &self.channel_transaction_parameters,
+                                                         funding_redeemscript.clone(), self.channel_value_satoshis,
+                                                         obscure_factor,
+                                                         holder_commitment_tx, best_block);
 
                channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_bitcoin_tx.txid, Vec::new(), self.cur_counterparty_commitment_transaction_number, self.counterparty_cur_commitment_point.unwrap(), logger);
 
@@ -1655,7 +1686,7 @@ impl<Signer: Sign> Channel<Signer> {
                self.cur_holder_commitment_transaction_number -= 1;
                self.cur_counterparty_commitment_transaction_number -= 1;
 
-               Ok(channel_monitor)
+               Ok((channel_monitor, self.funding_transaction.as_ref().cloned().unwrap()))
        }
 
        pub fn funding_locked(&mut self, msg: &msgs::FundingLocked) -> Result<(), ChannelError> {
@@ -2285,6 +2316,16 @@ impl<Signer: Sign> Channel<Signer> {
                }, commitment_signed, closing_signed, monitor_update))
        }
 
+       /// Public version of the below, checking relevant preconditions first.
+       /// If we're not in a state where freeing the holding cell makes sense, this is a no-op and
+       /// returns `(None, Vec::new())`.
+       pub fn maybe_free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
+               if self.channel_state >= ChannelState::ChannelFunded as u32 &&
+                  (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
+                       self.free_holding_cell_htlcs(logger)
+               } else { Ok((None, Vec::new())) }
+       }
+
        /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
        /// fulfilling or failing the last pending HTLC)
        fn free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
@@ -2349,7 +2390,7 @@ impl<Signer: Sign> Channel<Signer> {
                                                }
                                        },
                                        &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
-                                               match self.get_update_fail_htlc(htlc_id, err_packet.clone()) {
+                                               match self.get_update_fail_htlc(htlc_id, err_packet.clone(), logger) {
                                                        Ok(update_fail_msg_option) => update_fail_htlcs.push(update_fail_msg_option.unwrap()),
                                                        Err(e) => {
                                                                if let ChannelError::Ignore(_) = e {}
@@ -2662,19 +2703,16 @@ impl<Signer: Sign> Channel<Signer> {
                }
        }
 
-       /// Removes any uncommitted HTLCs, to be used on peer disconnection, including any pending
-       /// HTLCs that we intended to add but haven't as we were waiting on a remote revoke.
-       /// Returns the set of PendingHTLCStatuses from remote uncommitted HTLCs (which we're
-       /// implicitly dropping) and the payment_hashes of HTLCs we tried to add but are dropping.
+       /// Removes any uncommitted inbound HTLCs and resets the state of uncommitted outbound HTLC
+       /// updates, to be used on peer disconnection. After this, update_*_htlc messages need to be
+       /// resent.
        /// No further message handling calls may be made until a channel_reestablish dance has
        /// completed.
-       pub fn remove_uncommitted_htlcs_and_mark_paused<L: Deref>(&mut self, logger: &L) -> Vec<(HTLCSource, PaymentHash)> where L::Target: Logger {
-               let mut outbound_drops = Vec::new();
-
+       pub fn remove_uncommitted_htlcs_and_mark_paused<L: Deref>(&mut self, logger: &L)  where L::Target: Logger {
                assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
                if self.channel_state < ChannelState::FundingSent as u32 {
                        self.channel_state = ChannelState::ShutdownComplete as u32;
-                       return outbound_drops;
+                       return;
                }
                // Upon reconnect we have to start the closing_signed dance over, but shutdown messages
                // will be retransmitted.
@@ -2717,23 +2755,8 @@ impl<Signer: Sign> Channel<Signer> {
                        }
                }
 
-               self.holding_cell_htlc_updates.retain(|htlc_update| {
-                       match htlc_update {
-                               // Note that currently on channel reestablish we assert that there are
-                               // no holding cell HTLC update_adds, so if in the future we stop
-                               // dropping added HTLCs here and failing them backwards, then there will
-                               // need to be corresponding changes made in the Channel's re-establish
-                               // logic.
-                               &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
-                                       outbound_drops.push((source.clone(), payment_hash.clone()));
-                                       false
-                               },
-                               &HTLCUpdateAwaitingACK::ClaimHTLC {..} | &HTLCUpdateAwaitingACK::FailHTLC {..} => true,
-                       }
-               });
                self.channel_state |= ChannelState::PeerDisconnected as u32;
-               log_debug!(logger, "Peer disconnection resulted in {} remote-announced HTLC drops and {} waiting-to-locally-announced HTLC drops on channel {}", outbound_drops.len(), inbound_drop_count, log_bytes!(self.channel_id()));
-               outbound_drops
+               log_debug!(logger, "Peer disconnection resulted in {} remote-announced HTLC drops on channel {}", inbound_drop_count, log_bytes!(self.channel_id()));
        }
 
        /// Indicates that a ChannelMonitor update failed to be stored by the client and further
@@ -2756,20 +2779,21 @@ impl<Signer: Sign> Channel<Signer> {
        /// Indicates that the latest ChannelMonitor update has been committed by the client
        /// successfully and we should restore normal operation. Returns messages which should be sent
        /// to the remote side.
-       pub fn monitor_updating_restored<L: Deref>(&mut self, logger: &L) -> (Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, RAACommitmentOrder, Vec<(PendingHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, bool, Option<msgs::FundingLocked>) where L::Target: Logger {
+       pub fn monitor_updating_restored<L: Deref>(&mut self, logger: &L) -> (Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, RAACommitmentOrder, Vec<(PendingHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, Option<Transaction>, Option<msgs::FundingLocked>) where L::Target: Logger {
                assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, ChannelState::MonitorUpdateFailed as u32);
                self.channel_state &= !(ChannelState::MonitorUpdateFailed as u32);
 
-               let needs_broadcast_safe = self.channel_state & (ChannelState::FundingSent as u32) != 0 && self.is_outbound();
+               let funding_broadcastable = if self.channel_state & (ChannelState::FundingSent as u32) != 0 && self.is_outbound() {
+                       self.funding_transaction.take()
+               } else { None };
 
-               // Because we will never generate a FundingBroadcastSafe event when we're in
-               // MonitorUpdateFailed, if we assume the user only broadcast the funding transaction when
-               // they received the FundingBroadcastSafe event, we can only ever hit
-               // monitor_pending_funding_locked when we're an inbound channel which failed to persist the
-               // monitor on funding_created, and we even got the funding transaction confirmed before the
-               // monitor was persisted.
+               // We will never broadcast the funding transaction when we're in MonitorUpdateFailed (and
+               // we assume the user never directly broadcasts the funding transaction and waits for us to
+               // do it). Thus, we can only ever hit monitor_pending_funding_locked when we're an inbound
+               // channel which failed to persist the monitor on funding_created, and we got the funding
+               // transaction confirmed before the monitor was persisted.
                let funding_locked = if self.monitor_pending_funding_locked {
-                       assert!(!self.is_outbound(), "Funding transaction broadcast without FundingBroadcastSafe!");
+                       assert!(!self.is_outbound(), "Funding transaction broadcast by the local client before it should have - LDK didn't do it!");
                        self.monitor_pending_funding_locked = false;
                        let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
                        Some(msgs::FundingLocked {
@@ -2786,7 +2810,7 @@ impl<Signer: Sign> Channel<Signer> {
                if self.channel_state & (ChannelState::PeerDisconnected as u32) != 0 {
                        self.monitor_pending_revoke_and_ack = false;
                        self.monitor_pending_commitment_signed = false;
-                       return (None, None, RAACommitmentOrder::RevokeAndACKFirst, forwards, failures, needs_broadcast_safe, funding_locked);
+                       return (None, None, RAACommitmentOrder::RevokeAndACKFirst, forwards, failures, funding_broadcastable, funding_locked);
                }
 
                let raa = if self.monitor_pending_revoke_and_ack {
@@ -2800,11 +2824,11 @@ impl<Signer: Sign> Channel<Signer> {
                self.monitor_pending_commitment_signed = false;
                let order = self.resend_order.clone();
                log_trace!(logger, "Restored monitor updating resulting in {}{} commitment update and {} RAA, with {} first",
-                       if needs_broadcast_safe { "a funding broadcast safe, " } else { "" },
+                       if funding_broadcastable.is_some() { "a funding broadcastable, " } else { "" },
                        if commitment_update.is_some() { "a" } else { "no" },
                        if raa.is_some() { "an" } else { "no" },
                        match order { RAACommitmentOrder::CommitmentFirst => "commitment", RAACommitmentOrder::RevokeAndACKFirst => "RAA"});
-               (raa, commitment_update, order, forwards, failures, needs_broadcast_safe, funding_locked)
+               (raa, commitment_update, order, forwards, failures, funding_broadcastable, funding_locked)
        }
 
        pub fn update_fee<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::UpdateFee) -> Result<(), ChannelError>
@@ -2891,7 +2915,7 @@ impl<Signer: Sign> Channel<Signer> {
 
        /// May panic if some calls other than message-handling calls (which will all Err immediately)
        /// have been called between remove_uncommitted_htlcs_and_mark_paused and this call.
-       pub fn channel_reestablish<L: Deref>(&mut self, msg: &msgs::ChannelReestablish, logger: &L) -> Result<(Option<msgs::FundingLocked>, Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, Option<ChannelMonitorUpdate>, RAACommitmentOrder, Option<msgs::Shutdown>), ChannelError> where L::Target: Logger {
+       pub fn channel_reestablish<L: Deref>(&mut self, msg: &msgs::ChannelReestablish, logger: &L) -> Result<(Option<msgs::FundingLocked>, Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, Option<ChannelMonitorUpdate>, RAACommitmentOrder, Vec<(HTLCSource, PaymentHash)>, Option<msgs::Shutdown>), ChannelError> where L::Target: Logger {
                if self.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
                        // While BOLT 2 doesn't indicate explicitly we should error this channel here, it
                        // almost certainly indicates we are going to end up out-of-sync in some way, so we
@@ -2942,7 +2966,7 @@ impl<Signer: Sign> Channel<Signer> {
                                        return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent funding_locked yet".to_owned()));
                                }
                                // Short circuit the whole handler as there is nothing we can resend them
-                               return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg));
+                               return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, Vec::new(), shutdown_msg));
                        }
 
                        // We have OurFundingLocked set!
@@ -2950,7 +2974,7 @@ impl<Signer: Sign> Channel<Signer> {
                        return Ok((Some(msgs::FundingLocked {
                                channel_id: self.channel_id(),
                                next_per_commitment_point,
-                       }), None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg));
+                       }), None, None, None, RAACommitmentOrder::CommitmentFirst, Vec::new(), shutdown_msg));
                }
 
                let required_revoke = if msg.next_remote_commitment_number + 1 == INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
@@ -2991,14 +3015,6 @@ impl<Signer: Sign> Channel<Signer> {
                        }
 
                        if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
-                               // Note that if in the future we no longer drop holding cell update_adds on peer
-                               // disconnect, this logic will need to be updated.
-                               for htlc_update in self.holding_cell_htlc_updates.iter() {
-                                       if let &HTLCUpdateAwaitingACK::AddHTLC { .. } = htlc_update {
-                                               debug_assert!(false, "There shouldn't be any add-HTLCs in the holding cell now because they should have been dropped on peer disconnect. Panic here because said HTLCs won't be handled correctly.");
-                                       }
-                               }
-
                                // We're up-to-date and not waiting on a remote revoke (if we are our
                                // channel_reestablish should result in them sending a revoke_and_ack), but we may
                                // have received some updates while we were disconnected. Free the holding cell
@@ -3007,20 +3023,14 @@ impl<Signer: Sign> Channel<Signer> {
                                        Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)),
                                        Err(ChannelError::Ignore(_)) | Err(ChannelError::CloseDelayBroadcast(_)) => panic!("Got non-channel-failing result from free_holding_cell_htlcs"),
                                        Ok((Some((commitment_update, monitor_update)), htlcs_to_fail)) => {
-                                               // If in the future we no longer drop holding cell update_adds on peer
-                                               // disconnect, we may be handed some HTLCs to fail backwards here.
-                                               assert!(htlcs_to_fail.is_empty());
-                                               return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(monitor_update), self.resend_order.clone(), shutdown_msg));
+                                               return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(monitor_update), self.resend_order.clone(), htlcs_to_fail, shutdown_msg));
                                        },
                                        Ok((None, htlcs_to_fail)) => {
-                                               // If in the future we no longer drop holding cell update_adds on peer
-                                               // disconnect, we may be handed some HTLCs to fail backwards here.
-                                               assert!(htlcs_to_fail.is_empty());
-                                               return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), shutdown_msg));
+                                               return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), htlcs_to_fail, shutdown_msg));
                                        },
                                }
                        } else {
-                               return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), shutdown_msg));
+                               return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), Vec::new(), shutdown_msg));
                        }
                } else if msg.next_local_commitment_number == next_counterparty_commitment_number - 1 {
                        if required_revoke.is_some() {
@@ -3031,10 +3041,10 @@ impl<Signer: Sign> Channel<Signer> {
 
                        if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
                                self.monitor_pending_commitment_signed = true;
-                               return Ok((resend_funding_locked, None, None, None, self.resend_order.clone(), shutdown_msg));
+                               return Ok((resend_funding_locked, None, None, None, self.resend_order.clone(), Vec::new(), shutdown_msg));
                        }
 
-                       return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update(logger)), None, self.resend_order.clone(), shutdown_msg));
+                       return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update(logger)), None, self.resend_order.clone(), Vec::new(), shutdown_msg));
                } else {
                        return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction".to_owned()));
                }
@@ -3325,7 +3335,7 @@ impl<Signer: Sign> Channel<Signer> {
                        // Upper bound by capacity. We make it a bit less than full capacity to prevent attempts
                        // to use full capacity. This is an effort to reduce routing failures, because in many cases
                        // channel might have been used to route very small values (either by honest users or as DoS).
-                       self.channel_value_satoshis * 9 / 10,
+                       self.channel_value_satoshis * 1000 * 9 / 10,
 
                        Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis)
                );
@@ -3344,6 +3354,10 @@ impl<Signer: Sign> Channel<Signer> {
                self.config.fee_proportional_millionths
        }
 
+       pub fn get_cltv_expiry_delta(&self) -> u16 {
+               cmp::max(self.config.cltv_expiry_delta, MIN_CLTV_EXPIRY_DELTA)
+       }
+
        #[cfg(test)]
        pub fn get_feerate(&self) -> u32 {
                self.feerate_per_kw
@@ -3446,7 +3460,7 @@ impl<Signer: Sign> Channel<Signer> {
        /// is_usable() and considers things like the channel being temporarily disabled.
        /// Allowed in any state (including after shutdown)
        pub fn is_live(&self) -> bool {
-               self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) == 0)
+               self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32) == 0)
        }
 
        /// Returns true if this channel has been marked as awaiting a monitor update to move forward.
@@ -3470,46 +3484,147 @@ impl<Signer: Sign> Channel<Signer> {
                } else { false }
        }
 
-       pub fn to_disabled_staged(&mut self) {
-               self.network_sync = UpdateStatus::DisabledStaged;
+       pub fn channel_update_status(&self) -> ChannelUpdateStatus {
+               self.channel_update_status
        }
 
-       pub fn to_disabled_marked(&mut self) {
-               self.network_sync = UpdateStatus::DisabledMarked;
+       pub fn set_channel_update_status(&mut self, status: ChannelUpdateStatus) {
+               self.channel_update_status = status;
        }
 
-       pub fn to_fresh(&mut self) {
-               self.network_sync = UpdateStatus::Fresh;
-       }
+       fn check_get_funding_locked(&mut self, height: u32) -> Option<msgs::FundingLocked> {
+               if self.funding_tx_confirmation_height == 0 {
+                       return None;
+               }
+
+               let funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
+               if funding_tx_confirmations <= 0 {
+                       self.funding_tx_confirmation_height = 0;
+               }
 
-       pub fn is_disabled_staged(&self) -> bool {
-               self.network_sync == UpdateStatus::DisabledStaged
+               if funding_tx_confirmations < self.minimum_depth as i64 {
+                       return None;
+               }
+
+               let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
+               let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
+                       self.channel_state |= ChannelState::OurFundingLocked as u32;
+                       true
+               } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) {
+                       self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
+                       self.update_time_counter += 1;
+                       true
+               } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
+                       // We got a reorg but not enough to trigger a force close, just ignore.
+                       false
+               } else if self.channel_state < ChannelState::ChannelFunded as u32 {
+                       panic!("Started confirming a channel in a state pre-FundingSent?: {}", self.channel_state);
+               } else {
+                       // We got a reorg but not enough to trigger a force close, just ignore.
+                       false
+               };
+
+               if need_commitment_update {
+                       if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
+                               let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
+                               return Some(msgs::FundingLocked {
+                                       channel_id: self.channel_id,
+                                       next_per_commitment_point,
+                               });
+                       } else {
+                               self.monitor_pending_funding_locked = true;
+                       }
+               }
+               None
        }
 
-       pub fn is_disabled_marked(&self) -> bool {
-               self.network_sync == UpdateStatus::DisabledMarked
+       /// When a transaction is confirmed, we check whether it is or spends the funding transaction
+       /// In the first case, we store the confirmation height and calculating the short channel id.
+       /// In the second, we simply return an Err indicating we need to be force-closed now.
+       pub fn transactions_confirmed<L: Deref>(&mut self, block_hash: &BlockHash, height: u32, txdata: &TransactionData, logger: &L)
+                       -> Result<Option<msgs::FundingLocked>, msgs::ErrorMessage> where L::Target: Logger {
+               let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
+               for &(index_in_block, tx) in txdata.iter() {
+                       if let Some(funding_txo) = self.get_funding_txo() {
+                               // If we haven't yet sent a funding_locked, but are in FundingSent (ignoring
+                               // whether they've sent a funding_locked or not), check if we should send one.
+                               if non_shutdown_state & !(ChannelState::TheirFundingLocked as u32) == ChannelState::FundingSent as u32 {
+                                       if tx.txid() == funding_txo.txid {
+                                               let txo_idx = funding_txo.index as usize;
+                                               if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.get_funding_redeemscript().to_v0_p2wsh() ||
+                                                               tx.output[txo_idx].value != self.channel_value_satoshis {
+                                                       if self.is_outbound() {
+                                                               // If we generated the funding transaction and it doesn't match what it
+                                                               // should, the client is really broken and we should just panic and
+                                                               // tell them off. That said, because hash collisions happen with high
+                                                               // probability in fuzztarget mode, if we're fuzzing we just close the
+                                                               // channel and move on.
+                                                               #[cfg(not(feature = "fuzztarget"))]
+                                                               panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
+                                                       }
+                                                       self.update_time_counter += 1;
+                                                       return Err(msgs::ErrorMessage {
+                                                               channel_id: self.channel_id(),
+                                                               data: "funding tx had wrong script/value or output index".to_owned()
+                                                       });
+                                               } else {
+                                                       if self.is_outbound() {
+                                                               for input in tx.input.iter() {
+                                                                       if input.witness.is_empty() {
+                                                                               // We generated a malleable funding transaction, implying we've
+                                                                               // just exposed ourselves to funds loss to our counterparty.
+                                                                               #[cfg(not(feature = "fuzztarget"))]
+                                                                               panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
+                                                                       }
+                                                               }
+                                                       }
+                                                       self.funding_tx_confirmation_height = height;
+                                                       self.funding_tx_confirmed_in = Some(*block_hash);
+                                                       self.short_channel_id = match scid_from_parts(height as u64, index_in_block as u64, txo_idx as u64) {
+                                                               Ok(scid) => Some(scid),
+                                                               Err(_) => panic!("Block was bogus - either height was > 16 million, had > 16 million transactions, or had > 65k outputs"),
+                                                       }
+                                               }
+                                       }
+                                       // If we allow 1-conf funding, we may need to check for funding_locked here and
+                                       // send it immediately instead of waiting for a best_block_updated call (which
+                                       // may have already happened for this block).
+                                       if let Some(funding_locked) = self.check_get_funding_locked(height) {
+                                               return Ok(Some(funding_locked));
+                                       }
+                               }
+                               for inp in tx.input.iter() {
+                                       if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
+                                               log_trace!(logger, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(self.channel_id()));
+                                               return Err(msgs::ErrorMessage {
+                                                       channel_id: self.channel_id(),
+                                                       data: "Commitment or closing transaction was confirmed on chain.".to_owned()
+                                               });
+                                       }
+                               }
+                       }
+               }
+               Ok(None)
        }
 
-       /// When we receive a new block, we (a) check whether the block contains the funding
-       /// transaction (which would start us counting blocks until we send the funding_signed), and
-       /// (b) check the height of the block against outbound holding cell HTLCs in case we need to
-       /// give up on them prematurely and time them out. Everything else (e.g. commitment
-       /// transaction broadcasts, channel closure detection, HTLC transaction broadcasting, etc) is
+       /// When a new block is connected, we check the height of the block against outbound holding
+       /// cell HTLCs in case we need to give up on them prematurely and time them out. Everything
+       /// else (e.g. commitment transaction broadcasts, HTLC transaction broadcasting, etc) is
        /// handled by the ChannelMonitor.
        ///
        /// If we return Err, the channel may have been closed, at which point the standard
        /// requirements apply - no calls may be made except those explicitly stated to be allowed
        /// post-shutdown.
-       /// Only returns an ErrorAction of DisconnectPeer, if Err.
        ///
        /// May return some HTLCs (and their payment_hash) which have timed out and should be failed
        /// back.
-       pub fn block_connected(&mut self, header: &BlockHeader, txdata: &TransactionData, height: u32) -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage> {
+       pub fn best_block_updated(&mut self, height: u32, highest_header_time: u32) -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage> {
                let mut timed_out_htlcs = Vec::new();
+               let unforwarded_htlc_cltv_limit = height + HTLC_FAIL_BACK_BUFFER;
                self.holding_cell_htlc_updates.retain(|htlc_update| {
                        match htlc_update {
                                &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, ref cltv_expiry, .. } => {
-                                       if *cltv_expiry <= height + HTLC_FAIL_BACK_BUFFER {
+                                       if *cltv_expiry <= unforwarded_htlc_cltv_limit {
                                                timed_out_htlcs.push((source.clone(), payment_hash.clone()));
                                                false
                                        } else { true }
@@ -3517,119 +3632,63 @@ impl<Signer: Sign> Channel<Signer> {
                                _ => true
                        }
                });
-               let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
-               if header.block_hash() != self.last_block_connected {
-                       if self.funding_tx_confirmations > 0 {
-                               self.funding_tx_confirmations += 1;
-                       }
+
+               self.update_time_counter = cmp::max(self.update_time_counter, highest_header_time);
+
+               if let Some(funding_locked) = self.check_get_funding_locked(height) {
+                       return Ok((Some(funding_locked), timed_out_htlcs));
                }
-               if non_shutdown_state & !(ChannelState::TheirFundingLocked as u32) == ChannelState::FundingSent as u32 {
-                       for &(index_in_block, tx) in txdata.iter() {
-                               let funding_txo = self.get_funding_txo().unwrap();
-                               if tx.txid() == funding_txo.txid {
-                                       let txo_idx = funding_txo.index as usize;
-                                       if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.get_funding_redeemscript().to_v0_p2wsh() ||
-                                                       tx.output[txo_idx].value != self.channel_value_satoshis {
-                                               if self.is_outbound() {
-                                                       // If we generated the funding transaction and it doesn't match what it
-                                                       // should, the client is really broken and we should just panic and
-                                                       // tell them off. That said, because hash collisions happen with high
-                                                       // probability in fuzztarget mode, if we're fuzzing we just close the
-                                                       // channel and move on.
-                                                       #[cfg(not(feature = "fuzztarget"))]
-                                                       panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
-                                               }
-                                               self.channel_state = ChannelState::ShutdownComplete as u32;
-                                               self.update_time_counter += 1;
-                                               return Err(msgs::ErrorMessage {
-                                                       channel_id: self.channel_id(),
-                                                       data: "funding tx had wrong script/value".to_owned()
-                                               });
-                                       } else {
-                                               if self.is_outbound() {
-                                                       for input in tx.input.iter() {
-                                                               if input.witness.is_empty() {
-                                                                       // We generated a malleable funding transaction, implying we've
-                                                                       // just exposed ourselves to funds loss to our counterparty.
-                                                                       #[cfg(not(feature = "fuzztarget"))]
-                                                                       panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
-                                                               }
-                                                       }
-                                               }
-                                               if height > 0xff_ff_ff || (index_in_block) > 0xff_ff_ff {
-                                                       panic!("Block was bogus - either height 16 million or had > 16 million transactions");
-                                               }
-                                               assert!(txo_idx <= 0xffff); // txo_idx is a (u16 as usize), so this is just listed here for completeness
-                                               self.funding_tx_confirmations = 1;
-                                               self.short_channel_id = Some(((height as u64)         << (5*8)) |
-                                                                            ((index_in_block as u64) << (2*8)) |
-                                                                            ((txo_idx as u64)        << (0*8)));
-                                       }
-                               }
+
+               let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
+               if non_shutdown_state >= ChannelState::ChannelFunded as u32 ||
+                  (non_shutdown_state & ChannelState::OurFundingLocked as u32) == ChannelState::OurFundingLocked as u32 {
+                       let mut funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
+                       if self.funding_tx_confirmation_height == 0 {
+                               // Note that check_get_funding_locked may reset funding_tx_confirmation_height to
+                               // zero if it has been reorged out, however in either case, our state flags
+                               // indicate we've already sent a funding_locked
+                               funding_tx_confirmations = 0;
                        }
-               }
-               if header.block_hash() != self.last_block_connected {
-                       self.last_block_connected = header.block_hash();
-                       self.update_time_counter = cmp::max(self.update_time_counter, header.time);
-                       if self.funding_tx_confirmations > 0 {
-                               if self.funding_tx_confirmations == self.minimum_depth as u64 {
-                                       let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
-                                               self.channel_state |= ChannelState::OurFundingLocked as u32;
-                                               true
-                                       } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) {
-                                               self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
-                                               self.update_time_counter += 1;
-                                               true
-                                       } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
-                                               // We got a reorg but not enough to trigger a force close, just update
-                                               // funding_tx_confirmed_in and return.
-                                               false
-                                       } else if self.channel_state < ChannelState::ChannelFunded as u32 {
-                                               panic!("Started confirming a channel in a state pre-FundingSent?: {}", self.channel_state);
-                                       } else {
-                                               // We got a reorg but not enough to trigger a force close, just update
-                                               // funding_tx_confirmed_in and return.
-                                               false
-                                       };
-                                       self.funding_tx_confirmed_in = Some(self.last_block_connected);
-
-                                       //TODO: Note that this must be a duplicate of the previous commitment point they sent us,
-                                       //as otherwise we will have a commitment transaction that they can't revoke (well, kinda,
-                                       //they can by sending two revoke_and_acks back-to-back, but not really). This appears to be
-                                       //a protocol oversight, but I assume I'm just missing something.
-                                       if need_commitment_update {
-                                               if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
-                                                       let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
-                                                       return Ok((Some(msgs::FundingLocked {
-                                                               channel_id: self.channel_id,
-                                                               next_per_commitment_point,
-                                                       }), timed_out_htlcs));
-                                               } else {
-                                                       self.monitor_pending_funding_locked = true;
-                                                       return Ok((None, timed_out_htlcs));
-                                               }
-                                       }
-                               }
+
+                       // If we've sent funding_locked (or have both sent and received funding_locked), and
+                       // the funding transaction's confirmation count has dipped below minimum_depth / 2,
+                       // close the channel and hope we can get the latest state on chain (because presumably
+                       // the funding transaction is at least still in the mempool of most nodes).
+                       if funding_tx_confirmations < self.minimum_depth as i64 / 2 {
+                               return Err(msgs::ErrorMessage {
+                                       channel_id: self.channel_id(),
+                                       data: format!("Funding transaction was un-confirmed. Locked at {} confs, now have {} confs.", self.minimum_depth, funding_tx_confirmations),
+                               });
                        }
                }
+
                Ok((None, timed_out_htlcs))
        }
 
-       /// Called by channelmanager based on chain blocks being disconnected.
-       /// Returns true if we need to close the channel now due to funding transaction
-       /// unconfirmation/reorg.
-       pub fn block_disconnected(&mut self, header: &BlockHeader) -> bool {
-               if self.funding_tx_confirmations > 0 {
-                       self.funding_tx_confirmations -= 1;
-                       if self.funding_tx_confirmations == UNCONF_THRESHOLD as u64 {
-                               return true;
+       /// Indicates the funding transaction is no longer confirmed in the main chain. This may
+       /// force-close the channel, but may also indicate a harmless reorganization of a block or two
+       /// before the channel has reached funding_locked and we can just wait for more blocks.
+       pub fn funding_transaction_unconfirmed(&mut self) -> Result<(), msgs::ErrorMessage> {
+               if self.funding_tx_confirmation_height != 0 {
+                       // We handle the funding disconnection by calling best_block_updated with a height one
+                       // below where our funding was connected, implying a reorg back to conf_height - 1.
+                       let reorg_height = self.funding_tx_confirmation_height - 1;
+                       // We use the time field to bump the current time we set on channel updates if its
+                       // larger. If we don't know that time has moved forward, we can just set it to the last
+                       // time we saw and it will be ignored.
+                       let best_time = self.update_time_counter;
+                       match self.best_block_updated(reorg_height, best_time) {
+                               Ok((funding_locked, timed_out_htlcs)) => {
+                                       assert!(funding_locked.is_none(), "We can't generate a funding with 0 confirmations?");
+                                       assert!(timed_out_htlcs.is_empty(), "We can't have accepted HTLCs with a timeout before our funding confirmation?");
+                                       Ok(())
+                               },
+                               Err(e) => Err(e)
                        }
+               } else {
+                       // We never learned about the funding confirmation anyway, just ignore
+                       Ok(())
                }
-               self.last_block_connected = header.block_hash();
-               if Some(self.last_block_connected) == self.funding_tx_confirmed_in {
-                       self.funding_tx_confirmations = self.minimum_depth as u64 - 1;
-               }
-               false
        }
 
        // Methods to get unprompted messages to send to the remote end (or where we already returned
@@ -3721,7 +3780,7 @@ impl<Signer: Sign> Channel<Signer> {
        /// Note that channel_id changes during this call!
        /// Do NOT broadcast the funding transaction until after a successful funding_signed call!
        /// If an Err is returned, it is a ChannelError::Close.
-       pub fn get_outbound_funding_created<L: Deref>(&mut self, funding_txo: OutPoint, logger: &L) -> Result<msgs::FundingCreated, ChannelError> where L::Target: Logger {
+       pub fn get_outbound_funding_created<L: Deref>(&mut self, funding_transaction: Transaction, funding_txo: OutPoint, logger: &L) -> Result<msgs::FundingCreated, ChannelError> where L::Target: Logger {
                if !self.is_outbound() {
                        panic!("Tried to create outbound funding_created message on an inbound channel!");
                }
@@ -3752,6 +3811,7 @@ impl<Signer: Sign> Channel<Signer> {
 
                self.channel_state = ChannelState::FundingCreated as u32;
                self.channel_id = funding_txo.to_channel_id();
+               self.funding_transaction = Some(funding_transaction);
 
                Ok(msgs::FundingCreated {
                        temporary_channel_id,
@@ -3769,6 +3829,8 @@ impl<Signer: Sign> Channel<Signer> {
        /// closing).
        /// Note that the "channel must be funded" requirement is stricter than BOLT 7 requires - see
        /// https://github.com/lightningnetwork/lightning-rfc/issues/468
+       ///
+       /// This will only return ChannelError::Ignore upon failure.
        pub fn get_channel_announcement(&self, node_id: PublicKey, chain_hash: BlockHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> {
                if !self.config.announced_channel {
                        return Err(ChannelError::Ignore("Channel is not available for public announcements".to_owned()));
@@ -3799,6 +3861,63 @@ impl<Signer: Sign> Channel<Signer> {
                Ok((msg, sig))
        }
 
+       /// Signs the given channel announcement, returning a ChannelError::Ignore if no keys are
+       /// available.
+       fn sign_channel_announcement(&self, our_node_secret: &SecretKey, our_node_id: PublicKey, msghash: secp256k1::Message, announcement: msgs::UnsignedChannelAnnouncement, our_bitcoin_sig: Signature) -> Result<msgs::ChannelAnnouncement, ChannelError> {
+               if let Some((their_node_sig, their_bitcoin_sig)) = self.announcement_sigs {
+                       let were_node_one = announcement.node_id_1 == our_node_id;
+
+                       let our_node_sig = self.secp_ctx.sign(&msghash, our_node_secret);
+                       Ok(msgs::ChannelAnnouncement {
+                               node_signature_1: if were_node_one { our_node_sig } else { their_node_sig },
+                               node_signature_2: if were_node_one { their_node_sig } else { our_node_sig },
+                               bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { their_bitcoin_sig },
+                               bitcoin_signature_2: if were_node_one { their_bitcoin_sig } else { our_bitcoin_sig },
+                               contents: announcement,
+                       })
+               } else {
+                       Err(ChannelError::Ignore("Attempted to sign channel announcement before we'd received announcement_signatures".to_string()))
+               }
+       }
+
+       /// Processes an incoming announcement_signatures message, providing a fully-signed
+       /// channel_announcement message which we can broadcast and storing our counterparty's
+       /// signatures for later reconstruction/rebroadcast of the channel_announcement.
+       pub fn announcement_signatures(&mut self, our_node_secret: &SecretKey, our_node_id: PublicKey, chain_hash: BlockHash, msg: &msgs::AnnouncementSignatures) -> Result<msgs::ChannelAnnouncement, ChannelError> {
+               let (announcement, our_bitcoin_sig) = self.get_channel_announcement(our_node_id.clone(), chain_hash)?;
+
+               let msghash = hash_to_message!(&Sha256d::hash(&announcement.encode()[..])[..]);
+
+               if self.secp_ctx.verify(&msghash, &msg.node_signature, &self.get_counterparty_node_id()).is_err() {
+                       return Err(ChannelError::Close(format!(
+                               "Bad announcement_signatures. Failed to verify node_signature. UnsignedChannelAnnouncement used for verification is {:?}. their_node_key is {:?}",
+                                &announcement, self.get_counterparty_node_id())));
+               }
+               if self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, self.counterparty_funding_pubkey()).is_err() {
+                       return Err(ChannelError::Close(format!(
+                               "Bad announcement_signatures. Failed to verify bitcoin_signature. UnsignedChannelAnnouncement used for verification is {:?}. their_bitcoin_key is ({:?})",
+                               &announcement, self.counterparty_funding_pubkey())));
+               }
+
+               self.announcement_sigs = Some((msg.node_signature, msg.bitcoin_signature));
+
+               self.sign_channel_announcement(our_node_secret, our_node_id, msghash, announcement, our_bitcoin_sig)
+       }
+
+       /// Gets a signed channel_announcement for this channel, if we previously received an
+       /// announcement_signatures from our counterparty.
+       pub fn get_signed_channel_announcement(&self, our_node_secret: &SecretKey, our_node_id: PublicKey, chain_hash: BlockHash) -> Option<msgs::ChannelAnnouncement> {
+               let (announcement, our_bitcoin_sig) = match self.get_channel_announcement(our_node_id.clone(), chain_hash) {
+                       Ok(res) => res,
+                       Err(_) => return None,
+               };
+               let msghash = hash_to_message!(&Sha256d::hash(&announcement.encode()[..])[..]);
+               match self.sign_channel_announcement(our_node_secret, our_node_id, msghash, announcement, our_bitcoin_sig) {
+                       Ok(res) => Some(res),
+                       Err(_) => None,
+               }
+       }
+
        /// May panic if called on a channel that wasn't immediately-previously
        /// self.remove_uncommitted_htlcs_and_mark_paused()'d
        pub fn get_channel_reestablish<L: Deref>(&self, logger: &L) -> msgs::ChannelReestablish where L::Target: Logger {
@@ -3855,10 +3974,18 @@ impl<Signer: Sign> Channel<Signer> {
 
        /// Adds a pending outbound HTLC to this channel, note that you probably want
        /// send_htlc_and_commit instead cause you'll want both messages at once.
-       /// This returns an option instead of a pure UpdateAddHTLC as we may be in a state where we are
-       /// waiting on the remote peer to send us a revoke_and_ack during which time we cannot add new
-       /// HTLCs on the wire or we wouldn't be able to determine what they actually ACK'ed.
-       /// You MUST call send_commitment prior to any other calls on this Channel
+       ///
+       /// This returns an optional UpdateAddHTLC as we may be in a state where we cannot add HTLCs on
+       /// the wire:
+       /// * In cases where we're waiting on the remote peer to send us a revoke_and_ack, we
+       ///   wouldn't be able to determine what they actually ACK'ed if we have two sets of updates
+       ///   awaiting ACK.
+       /// * In cases where we're marked MonitorUpdateFailed, we cannot commit to a new state as we
+       ///   may not yet have sent the previous commitment update messages and will need to regenerate
+       ///   them.
+       ///
+       /// You MUST call send_commitment prior to calling any other methods on this Channel!
+       ///
        /// If an Err is returned, it's a ChannelError::Ignore!
        pub fn send_htlc(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result<Option<msgs::UpdateAddHTLC>, ChannelError> {
                if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
@@ -3877,14 +4004,14 @@ impl<Signer: Sign> Channel<Signer> {
                        return Err(ChannelError::Ignore(format!("Cannot send less than their minimum HTLC value ({})", self.counterparty_htlc_minimum_msat)));
                }
 
-               if (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
+               if (self.channel_state & (ChannelState::PeerDisconnected as u32)) != 0 {
                        // Note that this should never really happen, if we're !is_live() on receipt of an
                        // incoming HTLC for relay will result in us rejecting the HTLC and we won't allow
                        // the user to send directly into a !is_live() channel. However, if we
                        // disconnected during the time the previous hop was doing the commitment dance we may
                        // end up getting here after the forwarding delay. In any case, returning an
                        // IgnoreError will get ChannelManager to do the right thing and fail backwards now.
-                       return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected/frozen for channel monitor update".to_owned()));
+                       return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected from channel counterparty".to_owned()));
                }
 
                let (outbound_htlc_count, htlc_outbound_value_msat) = self.get_outbound_pending_htlc_stats();
@@ -3929,7 +4056,7 @@ impl<Signer: Sign> Channel<Signer> {
                }
 
                // Now update local state:
-               if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
+               if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
                        self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC {
                                amount_msat,
                                payment_hash,
@@ -4123,6 +4250,25 @@ impl<Signer: Sign> Channel<Signer> {
                }
        }
 
+       /// Get forwarding information for the counterparty.
+       pub fn counterparty_forwarding_info(&self) -> Option<CounterpartyForwardingInfo> {
+               self.counterparty_forwarding_info.clone()
+       }
+
+       pub fn channel_update(&mut self, msg: &msgs::ChannelUpdate) -> Result<(), ChannelError> {
+               let usable_channel_value_msat = (self.channel_value_satoshis - self.counterparty_selected_channel_reserve_satoshis) * 1000;
+               if msg.contents.htlc_minimum_msat >= usable_channel_value_msat {
+                       return Err(ChannelError::Close("Minimum htlc value is greater than channel value".to_string()));
+               }
+               self.counterparty_forwarding_info = Some(CounterpartyForwardingInfo {
+                       fee_base_msat: msg.contents.fee_base_msat,
+                       fee_proportional_millionths: msg.contents.fee_proportional_millionths,
+                       cltv_expiry_delta: msg.contents.cltv_expiry_delta
+               });
+
+               Ok(())
+       }
+
        /// Begins the shutdown process, getting a message for the remote peer and returning all
        /// holding cell HTLCs for payment failure.
        pub fn get_shutdown(&mut self) -> Result<(msgs::Shutdown, Vec<(HTLCSource, PaymentHash)>), APIError> {
@@ -4179,7 +4325,11 @@ impl<Signer: Sign> Channel<Signer> {
        /// those explicitly stated to be allowed after shutdown completes, eg some simple getters).
        /// Also returns the list of payment_hashes for channels which we can safely fail backwards
        /// immediately (others we will have to allow to time out).
-       pub fn force_shutdown(&mut self, should_broadcast: bool) -> (Option<OutPoint>, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>) {
+       pub fn force_shutdown(&mut self, should_broadcast: bool) -> (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>) {
+               // Note that we MUST only generate a monitor update that indicates force-closure - we're
+               // called during initialization prior to the chain_monitor in the encompassing ChannelManager
+               // being fully configured in some cases. Thus, its likely any monitor events we generate will
+               // be delayed in being processed! See the docs for `ChannelManagerReadArgs` for more.
                assert!(self.channel_state != ChannelState::ShutdownComplete as u32);
 
                // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
@@ -4193,7 +4343,7 @@ impl<Signer: Sign> Channel<Signer> {
                                _ => {}
                        }
                }
-               let funding_txo = if let Some(funding_txo) = self.get_funding_txo() {
+               let monitor_update = if let Some(funding_txo) = self.get_funding_txo() {
                        // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
                        // returning a channel monitor update here would imply a channel monitor update before
                        // we even registered the channel monitor to begin with, which is invalid.
@@ -4202,17 +4352,17 @@ impl<Signer: Sign> Channel<Signer> {
                        // monitor update to the user, even if we return one).
                        // See test_duplicate_chan_id and test_pre_lockin_no_chan_closed_update for more.
                        if self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelFunded as u32 | ChannelState::ShutdownComplete as u32) != 0 {
-                               Some(funding_txo.clone())
+                               self.latest_monitor_update_id += 1;
+                               Some((funding_txo, ChannelMonitorUpdate {
+                                       update_id: self.latest_monitor_update_id,
+                                       updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
+                               }))
                        } else { None }
                } else { None };
 
                self.channel_state = ChannelState::ShutdownComplete as u32;
                self.update_time_counter += 1;
-               self.latest_monitor_update_id += 1;
-               (funding_txo, ChannelMonitorUpdate {
-                       update_id: self.latest_monitor_update_id,
-                       updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
-               }, dropped_outbound_htlcs)
+               (monitor_update, dropped_outbound_htlcs)
        }
 }
 
@@ -4237,33 +4387,32 @@ fn is_unsupported_shutdown_script(their_features: &InitFeatures, script: &Script
 const SERIALIZATION_VERSION: u8 = 1;
 const MIN_SERIALIZATION_VERSION: u8 = 1;
 
-impl Writeable for InboundHTLCRemovalReason {
+impl_writeable_tlv_based_enum!(InboundHTLCRemovalReason,;
+       (0, FailRelay),
+       (1, FailMalformed),
+       (2, Fulfill),
+);
+
+impl Writeable for ChannelUpdateStatus {
        fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+               // We only care about writing out the current state as it was announced, ie only either
+               // Enabled or Disabled. In the case of DisabledStaged, we most recently announced the
+               // channel as enabled, so we write 0. For EnabledStaged, we similarly write a 1.
                match self {
-                       &InboundHTLCRemovalReason::FailRelay(ref error_packet) => {
-                               0u8.write(writer)?;
-                               error_packet.write(writer)?;
-                       },
-                       &InboundHTLCRemovalReason::FailMalformed((ref onion_hash, ref err_code)) => {
-                               1u8.write(writer)?;
-                               onion_hash.write(writer)?;
-                               err_code.write(writer)?;
-                       },
-                       &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
-                               2u8.write(writer)?;
-                               payment_preimage.write(writer)?;
-                       },
+                       ChannelUpdateStatus::Enabled => 0u8.write(writer)?,
+                       ChannelUpdateStatus::DisabledStaged => 0u8.write(writer)?,
+                       ChannelUpdateStatus::EnabledStaged => 1u8.write(writer)?,
+                       ChannelUpdateStatus::Disabled => 1u8.write(writer)?,
                }
                Ok(())
        }
 }
 
-impl Readable for InboundHTLCRemovalReason {
+impl Readable for ChannelUpdateStatus {
        fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
                Ok(match <u8 as Readable>::read(reader)? {
-                       0 => InboundHTLCRemovalReason::FailRelay(Readable::read(reader)?),
-                       1 => InboundHTLCRemovalReason::FailMalformed((Readable::read(reader)?, Readable::read(reader)?)),
-                       2 => InboundHTLCRemovalReason::Fulfill(Readable::read(reader)?),
+                       0 => ChannelUpdateStatus::Enabled,
+                       1 => ChannelUpdateStatus::Disabled,
                        _ => return Err(DecodeError::InvalidValue),
                })
        }
@@ -4272,10 +4421,9 @@ impl Readable for InboundHTLCRemovalReason {
 impl<Signer: Sign> Writeable for Channel<Signer> {
        fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
                // Note that we write out as if remove_uncommitted_htlcs_and_mark_paused had just been
-               // called but include holding cell updates (and obviously we don't modify self).
+               // called.
 
-               writer.write_all(&[SERIALIZATION_VERSION; 1])?;
-               writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
+               write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
 
                self.user_id.write(writer)?;
                self.config.write(writer)?;
@@ -4288,8 +4436,8 @@ impl<Signer: Sign> Writeable for Channel<Signer> {
 
                let mut key_data = VecWriter(Vec::new());
                self.holder_signer.write(&mut key_data)?;
-               assert!(key_data.0.len() < std::usize::MAX);
-               assert!(key_data.0.len() < std::u32::MAX as usize);
+               assert!(key_data.0.len() < core::usize::MAX);
+               assert!(key_data.0.len() < core::u32::MAX as usize);
                (key_data.0.len() as u32).write(writer)?;
                writer.write_all(&key_data.0[..])?;
 
@@ -4350,9 +4498,10 @@ impl<Signer: Sign> Writeable for Channel<Signer> {
                                &OutboundHTLCState::Committed => {
                                        1u8.write(writer)?;
                                },
-                               &OutboundHTLCState::RemoteRemoved(ref fail_reason) => {
-                                       2u8.write(writer)?;
-                                       fail_reason.write(writer)?;
+                               &OutboundHTLCState::RemoteRemoved(_) => {
+                                       // Treat this as a Committed because we haven't received the CS - they'll
+                                       // resend the claim/fail on reconnect as we all (hopefully) the missing CS.
+                                       1u8.write(writer)?;
                                },
                                &OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref fail_reason) => {
                                        3u8.write(writer)?;
@@ -4430,11 +4579,9 @@ impl<Signer: Sign> Writeable for Channel<Signer> {
                }
 
                self.funding_tx_confirmed_in.write(writer)?;
+               self.funding_tx_confirmation_height.write(writer)?;
                self.short_channel_id.write(writer)?;
 
-               self.last_block_connected.write(writer)?;
-               self.funding_tx_confirmations.write(writer)?;
-
                self.counterparty_dust_limit_satoshis.write(writer)?;
                self.holder_dust_limit_satoshis.write(writer)?;
                self.counterparty_max_htlc_value_in_flight_msat.write(writer)?;
@@ -4444,15 +4591,31 @@ impl<Signer: Sign> Writeable for Channel<Signer> {
                self.counterparty_max_accepted_htlcs.write(writer)?;
                self.minimum_depth.write(writer)?;
 
+               match &self.counterparty_forwarding_info {
+                       Some(info) => {
+                               1u8.write(writer)?;
+                               info.fee_base_msat.write(writer)?;
+                               info.fee_proportional_millionths.write(writer)?;
+                               info.cltv_expiry_delta.write(writer)?;
+                       },
+                       None => 0u8.write(writer)?
+               }
+
                self.channel_transaction_parameters.write(writer)?;
-               self.counterparty_cur_commitment_point.write(writer)?;
+               self.funding_transaction.write(writer)?;
 
+               self.counterparty_cur_commitment_point.write(writer)?;
                self.counterparty_prev_commitment_point.write(writer)?;
                self.counterparty_node_id.write(writer)?;
 
                self.counterparty_shutdown_scriptpubkey.write(writer)?;
 
                self.commitment_secrets.write(writer)?;
+
+               self.channel_update_status.write(writer)?;
+
+               write_tlv_fields!(writer, {}, {(0, self.announcement_sigs)});
+
                Ok(())
        }
 }
@@ -4461,11 +4624,7 @@ const MAX_ALLOC_SIZE: usize = 64*1024;
 impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel<Signer>
                where K::Target: KeysInterface<Signer = Signer> {
        fn read<R : ::std::io::Read>(reader: &mut R, keys_source: &'a K) -> Result<Self, DecodeError> {
-               let _ver: u8 = Readable::read(reader)?;
-               let min_ver: u8 = Readable::read(reader)?;
-               if min_ver > SERIALIZATION_VERSION {
-                       return Err(DecodeError::UnknownVersion);
-               }
+               let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
 
                let user_id = Readable::read(reader)?;
                let config: ChannelConfig = Readable::read(reader)?;
@@ -4592,11 +4751,9 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel<Signer>
                };
 
                let funding_tx_confirmed_in = Readable::read(reader)?;
+               let funding_tx_confirmation_height = Readable::read(reader)?;
                let short_channel_id = Readable::read(reader)?;
 
-               let last_block_connected = Readable::read(reader)?;
-               let funding_tx_confirmations = Readable::read(reader)?;
-
                let counterparty_dust_limit_satoshis = Readable::read(reader)?;
                let holder_dust_limit_satoshis = Readable::read(reader)?;
                let counterparty_max_htlc_value_in_flight_msat = Readable::read(reader)?;
@@ -4606,7 +4763,19 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel<Signer>
                let counterparty_max_accepted_htlcs = Readable::read(reader)?;
                let minimum_depth = Readable::read(reader)?;
 
+               let counterparty_forwarding_info = match <u8 as Readable>::read(reader)? {
+                       0 => None,
+                       1 => Some(CounterpartyForwardingInfo {
+                               fee_base_msat: Readable::read(reader)?,
+                               fee_proportional_millionths: Readable::read(reader)?,
+                               cltv_expiry_delta: Readable::read(reader)?,
+                       }),
+                       _ => return Err(DecodeError::InvalidValue),
+               };
+
                let channel_parameters = Readable::read(reader)?;
+               let funding_transaction = Readable::read(reader)?;
+
                let counterparty_cur_commitment_point = Readable::read(reader)?;
 
                let counterparty_prev_commitment_point = Readable::read(reader)?;
@@ -4615,6 +4784,11 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel<Signer>
                let counterparty_shutdown_scriptpubkey = Readable::read(reader)?;
                let commitment_secrets = Readable::read(reader)?;
 
+               let channel_update_status = Readable::read(reader)?;
+
+               let mut announcement_sigs = None;
+               read_tlv_fields!(reader, {}, {(0, announcement_sigs)});
+
                let mut secp_ctx = Secp256k1::new();
                secp_ctx.seeded_randomize(&keys_source.get_secure_random_bytes());
 
@@ -4664,9 +4838,8 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel<Signer>
                        last_sent_closing_fee,
 
                        funding_tx_confirmed_in,
+                       funding_tx_confirmation_height,
                        short_channel_id,
-                       last_block_connected,
-                       funding_tx_confirmations,
 
                        counterparty_dust_limit_satoshis,
                        holder_dust_limit_satoshis,
@@ -4677,9 +4850,12 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel<Signer>
                        counterparty_max_accepted_htlcs,
                        minimum_depth,
 
+                       counterparty_forwarding_info,
+
                        channel_transaction_parameters: channel_parameters,
-                       counterparty_cur_commitment_point,
+                       funding_transaction,
 
+                       counterparty_cur_commitment_point,
                        counterparty_prev_commitment_point,
                        counterparty_node_id,
 
@@ -4687,7 +4863,9 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel<Signer>
 
                        commitment_secrets,
 
-                       network_sync: UpdateStatus::Fresh,
+                       channel_update_status,
+
+                       announcement_sigs,
 
                        #[cfg(any(test, feature = "fuzztarget"))]
                        next_local_commitment_tx_fee_info_cached: Mutex::new(None),
@@ -4708,26 +4886,30 @@ mod tests {
        use bitcoin::network::constants::Network;
        use bitcoin::hashes::hex::FromHex;
        use hex;
-       use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
-       use ln::channel::{Channel,Sign,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,HTLCCandidate,HTLCInitiator,TxCreationKeys};
+       use ln::{PaymentPreimage, PaymentHash};
+       use ln::channelmanager::{BestBlock, HTLCSource};
+       use ln::channel::{Channel,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,HTLCCandidate,HTLCInitiator,TxCreationKeys};
        use ln::channel::MAX_FUNDING_SATOSHIS;
        use ln::features::InitFeatures;
-       use ln::msgs::{OptionalField, DataLossProtect, DecodeError};
+       use ln::msgs::{ChannelUpdate, DataLossProtect, DecodeError, OptionalField, UnsignedChannelUpdate};
        use ln::chan_utils;
        use ln::chan_utils::{ChannelPublicKeys, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT};
        use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
-       use chain::keysinterface::{InMemorySigner, KeysInterface};
+       use chain::keysinterface::{InMemorySigner, KeysInterface, BaseSign};
        use chain::transaction::OutPoint;
        use util::config::UserConfig;
        use util::enforcing_trait_impls::EnforcingSigner;
        use util::test_utils;
        use util::logger::Logger;
        use bitcoin::secp256k1::{Secp256k1, Message, Signature, All};
+       use bitcoin::secp256k1::ffi::Signature as FFISignature;
        use bitcoin::secp256k1::key::{SecretKey,PublicKey};
+       use bitcoin::secp256k1::recovery::RecoverableSignature;
        use bitcoin::hashes::sha256::Hash as Sha256;
        use bitcoin::hashes::Hash;
        use bitcoin::hash_types::{Txid, WPubkeyHash};
        use std::sync::Arc;
+       use prelude::*;
 
        struct TestFeeEstimator {
                fee_est: u32
@@ -4769,6 +4951,7 @@ mod tests {
                }
                fn get_secure_random_bytes(&self) -> [u8; 32] { [0; 32] }
                fn read_chan_signer(&self, _data: &[u8]) -> Result<Self::Signer, DecodeError> { panic!(); }
+               fn sign_invoice(&self, _invoice_preimage: Vec<u8>) -> Result<RecoverableSignature, ()> { panic!(); }
        }
 
        fn public_from_secret_hex(secp_ctx: &Secp256k1<All>, hex: &str) -> PublicKey {
@@ -4818,7 +5001,6 @@ mod tests {
                // Create Node B's channel by receiving Node A's open_channel message
                // Make sure A's dust limit is as we expect.
                let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
-               assert_eq!(open_channel_msg.dust_limit_satoshis, 1560);
                let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
                let node_b_chan = Channel::<EnforcingSigner>::new_from_req(&&feeest, &&keys_provider, node_b_node_id, InitFeatures::known(), &open_channel_msg, 7, &config).unwrap();
 
@@ -4826,6 +5008,7 @@ mod tests {
                let mut accept_channel_msg = node_b_chan.get_accept_channel();
                accept_channel_msg.dust_limit_satoshis = 546;
                node_a_chan.accept_channel(&accept_channel_msg, &config, InitFeatures::known()).unwrap();
+               node_a_chan.holder_dust_limit_satoshis = 1560;
 
                // Put some inbound and outbound HTLCs in A's channel.
                let htlc_amount_msat = 11_092_000; // put an amount below A's effective dust limit but above B's.
@@ -4920,6 +5103,8 @@ mod tests {
                let secp_ctx = Secp256k1::new();
                let seed = [42; 32];
                let network = Network::Testnet;
+               let best_block = BestBlock::from_genesis(network);
+               let chain_hash = best_block.block_hash();
                let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
 
                // Go through the flow of opening a channel between two nodes.
@@ -4930,7 +5115,7 @@ mod tests {
                let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, 10000000, 100000, 42, &config).unwrap();
 
                // Create Node B's channel by receiving Node A's open_channel message
-               let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
+               let open_channel_msg = node_a_chan.get_open_channel(chain_hash);
                let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
                let mut node_b_chan = Channel::<EnforcingSigner>::new_from_req(&&feeest, &&keys_provider, node_b_node_id, InitFeatures::known(), &open_channel_msg, 7, &config).unwrap();
 
@@ -4944,11 +5129,11 @@ mod tests {
                        value: 10000000, script_pubkey: output_script.clone(),
                }]};
                let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
-               let funding_created_msg = node_a_chan.get_outbound_funding_created(funding_outpoint, &&logger).unwrap();
-               let (funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, &&logger).unwrap();
+               let funding_created_msg = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).unwrap();
+               let (funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&logger).unwrap();
 
                // Node B --> Node A: funding signed
-               let _ = node_a_chan.funding_signed(&funding_signed_msg, &&logger);
+               let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&logger);
 
                // Now disconnect the two nodes and check that the commitment point in
                // Node B's channel_reestablish message is sane.
@@ -4977,6 +5162,54 @@ mod tests {
                }
        }
 
+       #[test]
+       fn channel_update() {
+               let feeest = TestFeeEstimator{fee_est: 15000};
+               let secp_ctx = Secp256k1::new();
+               let seed = [42; 32];
+               let network = Network::Testnet;
+               let chain_hash = genesis_block(network).header.block_hash();
+               let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
+
+               // Create a channel.
+               let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
+               let config = UserConfig::default();
+               let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, 10000000, 100000, 42, &config).unwrap();
+               assert!(node_a_chan.counterparty_forwarding_info.is_none());
+               assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1); // the default
+               assert!(node_a_chan.counterparty_forwarding_info().is_none());
+
+               // Make sure that receiving a channel update will update the Channel as expected.
+               let update = ChannelUpdate {
+                       contents: UnsignedChannelUpdate {
+                               chain_hash,
+                               short_channel_id: 0,
+                               timestamp: 0,
+                               flags: 0,
+                               cltv_expiry_delta: 100,
+                               htlc_minimum_msat: 5,
+                               htlc_maximum_msat: OptionalField::Absent,
+                               fee_base_msat: 110,
+                               fee_proportional_millionths: 11,
+                               excess_data: Vec::new(),
+                       },
+                       signature: Signature::from(unsafe { FFISignature::new() })
+               };
+               node_a_chan.channel_update(&update).unwrap();
+
+               // The counterparty can send an update with a higher minimum HTLC, but that shouldn't
+               // change our official htlc_minimum_msat.
+               assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1);
+               match node_a_chan.counterparty_forwarding_info() {
+                       Some(info) => {
+                               assert_eq!(info.cltv_expiry_delta, 100);
+                               assert_eq!(info.fee_base_msat, 110);
+                               assert_eq!(info.fee_proportional_millionths, 11);
+                       },
+                       None => panic!("expected counterparty forwarding info to be Some")
+               }
+       }
+
        #[test]
        fn outbound_commitment_test() {
                // Test vectors from BOLT 3 Appendix C: