Clean up and clarify tx broadcast checks in channelmonitor tests
[rust-lightning] / src / ln / channel.rs
index b2d6a70e13ae3b5f79910df694a667781fdc1273..3a627f35baa9548881e8e52f8b1f888abff791a6 100644 (file)
@@ -16,7 +16,7 @@ use crypto::hkdf::{hkdf_extract,hkdf_expand};
 use ln::msgs;
 use ln::msgs::{ErrorAction, HandleError, MsgEncodable};
 use ln::channelmonitor::ChannelMonitor;
-use ln::channelmanager::{PendingHTLCStatus, PendingForwardHTLCInfo, HTLCFailReason, HTLCFailureMsg};
+use ln::channelmanager::{PendingHTLCStatus, HTLCSource, PendingForwardHTLCInfo, HTLCFailReason, HTLCFailureMsg};
 use ln::chan_utils::{TxCreationKeys,HTLCOutputInCommitment,HTLC_SUCCESS_TX_WEIGHT,HTLC_TIMEOUT_TX_WEIGHT};
 use ln::chan_utils;
 use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
@@ -87,24 +87,49 @@ impl ChannelKeys {
 }
 
 #[derive(PartialEq)]
-enum HTLCState {
+enum InboundHTLCState {
        /// Added by remote, to be included in next local commitment tx.
-       /// Implies HTLCOutput::outbound: false
        RemoteAnnounced,
        /// Included in a received commitment_signed message (implying we've revoke_and_ack'ed it), but
        /// the remote side hasn't yet revoked their previous state, which we need them to do before we
        /// accept this HTLC. Implies AwaitingRemoteRevoke.
        /// We also have not yet included this HTLC in a commitment_signed message, and are waiting on
        /// a remote revoke_and_ack on a previous state before we can do so.
-       /// Implies HTLCOutput::outbound: false
        AwaitingRemoteRevokeToAnnounce,
        /// Included in a received commitment_signed message (implying we've revoke_and_ack'ed it), but
        /// the remote side hasn't yet revoked their previous state, which we need them to do before we
        /// accept this HTLC. Implies AwaitingRemoteRevoke.
        /// We have included this HTLC in our latest commitment_signed and are now just waiting on a
        /// revoke_and_ack.
-       /// Implies HTLCOutput::outbound: true
        AwaitingAnnouncedRemoteRevoke,
+       Committed,
+       /// Removed by us and a new commitment_signed was sent (if we were AwaitingRemoteRevoke when we
+       /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
+       /// we'll drop it.
+       /// Note that we have to keep an eye on the HTLC until we've received a broadcastable
+       /// commitment transaction without it as otherwise we'll have to force-close the channel to
+       /// claim it before the timeout (obviously doesn't apply to revoked HTLCs that we can't claim
+       /// anyway). That said, ChannelMonitor does this for us (see
+       /// ChannelMonitor::would_broadcast_at_height) so we actually remove the HTLC from our own
+       /// local state before then, once we're sure that the next commitment_signed and
+       /// ChannelMonitor::provide_latest_local_commitment_tx_info will not include this HTLC.
+       LocalRemoved,
+}
+
+struct InboundHTLCOutput {
+       htlc_id: u64,
+       amount_msat: u64,
+       cltv_expiry: u32,
+       payment_hash: [u8; 32],
+       state: InboundHTLCState,
+       /// If we're in LocalRemoved, set to true if we fulfilled the HTLC, and can claim money
+       local_removed_fulfilled: bool,
+       /// state pre-Committed implies pending_forward_state, otherwise it must be None
+       pending_forward_state: Option<PendingHTLCStatus>,
+}
+
+#[derive(PartialEq)]
+enum OutboundHTLCState {
        /// Added by us and included in a commitment_signed (if we were AwaitingRemoteRevoke when we
        /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
        /// we will promote to Committed (note that they may not accept it until the next time we
@@ -115,63 +140,43 @@ enum HTLCState {
        ///    allowed to remove it, the "can only be removed once committed on both sides" requirement
        ///    doesn't matter to us and its up to them to enforce it, worst-case they jump ahead but
        ///    we'll never get out of sync).
-       /// Implies HTLCOutput::outbound: true
        LocalAnnounced,
        Committed,
        /// Remote removed this (outbound) HTLC. We're waiting on their commitment_signed to finalize
        /// the change (though they'll need to revoke before we fail the payment).
-       /// Implies HTLCOutput::outbound: true
        RemoteRemoved,
        /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
        /// the remote side hasn't yet revoked their previous state, which we need them to do before we
        /// can do any backwards failing. Implies AwaitingRemoteRevoke.
        /// We also have not yet removed this HTLC in a commitment_signed message, and are waiting on a
        /// remote revoke_and_ack on a previous state before we can do so.
-       /// Implies HTLCOutput::outbound: true
        AwaitingRemoteRevokeToRemove,
        /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
        /// the remote side hasn't yet revoked their previous state, which we need them to do before we
        /// can do any backwards failing. Implies AwaitingRemoteRevoke.
        /// We have removed this HTLC in our latest commitment_signed and are now just waiting on a
        /// revoke_and_ack to drop completely.
-       /// Implies HTLCOutput::outbound: true
        AwaitingRemovedRemoteRevoke,
-       /// Removed by us and a new commitment_signed was sent (if we were AwaitingRemoteRevoke when we
-       /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
-       /// we'll drop it.
-       /// Note that we have to keep an eye on the HTLC until we've received a broadcastable
-       /// commitment transaction without it as otherwise we'll have to force-close the channel to
-       /// claim it before the timeout (obviously doesn't apply to revoked HTLCs that we can't claim
-       /// anyway). That said, ChannelMonitor does this for us (see
-       /// ChannelMonitor::would_broadcast_at_height) so we actually remove the HTLC from our own
-       /// local state before then, once we're sure that the next commitment_signed and
-       /// ChannelMonitor::provide_latest_local_commitment_tx_info will not include this HTLC.
-       /// Implies HTLCOutput::outbound: false
-       LocalRemoved,
 }
 
-struct HTLCOutput { //TODO: Refactor into Outbound/InboundHTLCOutput (will save memory and fewer panics)
-       outbound: bool, // ie to an HTLC-Timeout transaction
+struct OutboundHTLCOutput {
        htlc_id: u64,
        amount_msat: u64,
        cltv_expiry: u32,
        payment_hash: [u8; 32],
-       state: HTLCState,
-       /// If we're in a Remote* removed state, set if they failed, otherwise None
+       state: OutboundHTLCState,
+       source: HTLCSource,
+       /// If we're in a removed state, set if they failed, otherwise None
        fail_reason: Option<HTLCFailReason>,
-       /// If we're in LocalRemoved*, set to true if we fulfilled the HTLC, and can claim money
-       local_removed_fulfilled: bool,
-       /// state pre-committed Remote* implies pending_forward_state, otherwise it must be None
-       pending_forward_state: Option<PendingHTLCStatus>,
 }
 
-impl HTLCOutput {
-       fn get_in_commitment(&self, offered: bool) -> HTLCOutputInCommitment {
+macro_rules! get_htlc_in_commitment {
+       ($htlc: expr, $offered: expr) => {
                HTLCOutputInCommitment {
-                       offered: offered,
-                       amount_msat: self.amount_msat,
-                       cltv_expiry: self.cltv_expiry,
-                       payment_hash: self.payment_hash,
+                       offered: $offered,
+                       amount_msat: $htlc.amount_msat,
+                       cltv_expiry: $htlc.cltv_expiry,
+                       payment_hash: $htlc.payment_hash,
                        transaction_output_index: 0
                }
        }
@@ -184,15 +189,16 @@ enum HTLCUpdateAwaitingACK {
                amount_msat: u64,
                cltv_expiry: u32,
                payment_hash: [u8; 32],
+               source: HTLCSource,
                onion_routing_packet: msgs::OnionPacket,
                time_created: Instant, //TODO: Some kind of timeout thing-a-majig
        },
        ClaimHTLC {
                payment_preimage: [u8; 32],
-               payment_hash: [u8; 32], // Only here for effecient duplicate detection
+               htlc_id: u64,
        },
        FailHTLC {
-               payment_hash: [u8; 32],
+               htlc_id: u64,
                err_packet: msgs::OnionErrorPacket,
        },
 }
@@ -262,7 +268,8 @@ pub struct Channel {
        cur_local_commitment_transaction_number: u64,
        cur_remote_commitment_transaction_number: u64,
        value_to_self_msat: u64, // Excluding all pending_htlcs, excluding fees
-       pending_htlcs: Vec<HTLCOutput>,
+       pending_inbound_htlcs: Vec<InboundHTLCOutput>,
+       pending_outbound_htlcs: Vec<OutboundHTLCOutput>,
        holding_cell_htlc_updates: Vec<HTLCUpdateAwaitingACK>,
        next_local_htlc_id: u64,
        next_remote_htlc_id: u64,
@@ -421,7 +428,8 @@ impl Channel {
                        cur_local_commitment_transaction_number: (1 << 48) - 1,
                        cur_remote_commitment_transaction_number: (1 << 48) - 1,
                        value_to_self_msat: channel_value_satoshis * 1000 - push_msat,
-                       pending_htlcs: Vec::new(),
+                       pending_inbound_htlcs: Vec::new(),
+                       pending_outbound_htlcs: Vec::new(),
                        holding_cell_htlc_updates: Vec::new(),
                        next_local_htlc_id: 0,
                        next_remote_htlc_id: 0,
@@ -562,7 +570,7 @@ impl Channel {
                                                              &PublicKey::from_secret_key(&secp_ctx, &chan_keys.delayed_payment_base_key),
                                                              &chan_keys.htlc_base_key,
                                                              BREAKDOWN_TIMEOUT, our_channel_monitor_claim_script);
-               channel_monitor.set_their_htlc_base_key(&msg.htlc_basepoint);
+               channel_monitor.set_their_base_keys(&msg.htlc_basepoint, &msg.delayed_payment_basepoint);
                channel_monitor.set_their_to_self_delay(msg.to_self_delay);
 
                let mut chan = Channel {
@@ -578,7 +586,8 @@ impl Channel {
                        cur_local_commitment_transaction_number: (1 << 48) - 1,
                        cur_remote_commitment_transaction_number: (1 << 48) - 1,
                        value_to_self_msat: msg.push_msat,
-                       pending_htlcs: Vec::new(),
+                       pending_inbound_htlcs: Vec::new(),
+                       pending_outbound_htlcs: Vec::new(),
                        holding_cell_htlc_updates: Vec::new(),
                        next_local_htlc_id: 0,
                        next_remote_htlc_id: 0,
@@ -686,66 +695,83 @@ impl Channel {
                        ins
                };
 
-               let mut txouts: Vec<(TxOut, Option<HTLCOutputInCommitment>)> = Vec::with_capacity(self.pending_htlcs.len() + 2);
+               let mut txouts: Vec<(TxOut, Option<HTLCOutputInCommitment>)> = Vec::with_capacity(self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len() + 2);
 
                let dust_limit_satoshis = if local { self.our_dust_limit_satoshis } else { self.their_dust_limit_satoshis };
                let mut remote_htlc_total_msat = 0;
                let mut local_htlc_total_msat = 0;
                let mut value_to_self_msat_offset = 0;
 
-               for ref htlc in self.pending_htlcs.iter() {
-                       let include = match htlc.state {
-                               HTLCState::RemoteAnnounced => !generated_by_local,
-                               HTLCState::AwaitingRemoteRevokeToAnnounce => !generated_by_local,
-                               HTLCState::AwaitingAnnouncedRemoteRevoke => true,
-                               HTLCState::LocalAnnounced => generated_by_local,
-                               HTLCState::Committed => true,
-                               HTLCState::RemoteRemoved => generated_by_local,
-                               HTLCState::AwaitingRemoteRevokeToRemove => generated_by_local,
-                               HTLCState::AwaitingRemovedRemoteRevoke => false,
-                               HTLCState::LocalRemoved => !generated_by_local,
-                       };
-
-                       if include {
-                               if htlc.outbound == local { // "offered HTLC output"
-                                       if htlc.amount_msat / 1000 >= dust_limit_satoshis + (self.feerate_per_kw * HTLC_TIMEOUT_TX_WEIGHT / 1000) {
-                                               let htlc_in_tx = htlc.get_in_commitment(true);
+               macro_rules! add_htlc_output {
+                       ($htlc: expr, $outbound: expr) => {
+                               if $outbound == local { // "offered HTLC output"
+                                       if $htlc.amount_msat / 1000 >= dust_limit_satoshis + (self.feerate_per_kw * HTLC_TIMEOUT_TX_WEIGHT / 1000) {
+                                               let htlc_in_tx = get_htlc_in_commitment!($htlc, true);
                                                txouts.push((TxOut {
                                                        script_pubkey: chan_utils::get_htlc_redeemscript(&htlc_in_tx, &keys).to_v0_p2wsh(),
-                                                       value: htlc.amount_msat / 1000
+                                                       value: $htlc.amount_msat / 1000
                                                }, Some(htlc_in_tx)));
                                        }
                                } else {
-                                       if htlc.amount_msat / 1000 >= dust_limit_satoshis + (self.feerate_per_kw * HTLC_SUCCESS_TX_WEIGHT / 1000) {
-                                               let htlc_in_tx = htlc.get_in_commitment(false);
+                                       if $htlc.amount_msat / 1000 >= dust_limit_satoshis + (self.feerate_per_kw * HTLC_SUCCESS_TX_WEIGHT / 1000) {
+                                               let htlc_in_tx = get_htlc_in_commitment!($htlc, false);
                                                txouts.push((TxOut { // "received HTLC output"
                                                        script_pubkey: chan_utils::get_htlc_redeemscript(&htlc_in_tx, &keys).to_v0_p2wsh(),
-                                                       value: htlc.amount_msat / 1000
+                                                       value: $htlc.amount_msat / 1000
                                                }, Some(htlc_in_tx)));
                                        }
-                               };
-                               if htlc.outbound {
-                                       local_htlc_total_msat += htlc.amount_msat;
-                               } else {
-                                       remote_htlc_total_msat += htlc.amount_msat;
                                }
+                       }
+               }
+
+               for ref htlc in self.pending_inbound_htlcs.iter() {
+                       let include = match htlc.state {
+                               InboundHTLCState::RemoteAnnounced => !generated_by_local,
+                               InboundHTLCState::AwaitingRemoteRevokeToAnnounce => !generated_by_local,
+                               InboundHTLCState::AwaitingAnnouncedRemoteRevoke => true,
+                               InboundHTLCState::Committed => true,
+                               InboundHTLCState::LocalRemoved => !generated_by_local,
+                       };
+
+                       if include {
+                               add_htlc_output!(htlc, false);
+                               remote_htlc_total_msat += htlc.amount_msat;
                        } else {
                                match htlc.state {
-                                       HTLCState::AwaitingRemoteRevokeToRemove|HTLCState::AwaitingRemovedRemoteRevoke => {
+                                       InboundHTLCState::LocalRemoved => {
+                                               if generated_by_local && htlc.local_removed_fulfilled {
+                                                       value_to_self_msat_offset += htlc.amount_msat as i64;
+                                               }
+                                       },
+                                       _ => {},
+                               }
+                       }
+               }
+
+               for ref htlc in self.pending_outbound_htlcs.iter() {
+                       let include = match htlc.state {
+                               OutboundHTLCState::LocalAnnounced => generated_by_local,
+                               OutboundHTLCState::Committed => true,
+                               OutboundHTLCState::RemoteRemoved => generated_by_local,
+                               OutboundHTLCState::AwaitingRemoteRevokeToRemove => generated_by_local,
+                               OutboundHTLCState::AwaitingRemovedRemoteRevoke => false,
+                       };
+
+                       if include {
+                               add_htlc_output!(htlc, true);
+                               local_htlc_total_msat += htlc.amount_msat;
+                       } else {
+                               match htlc.state {
+                                       OutboundHTLCState::AwaitingRemoteRevokeToRemove|OutboundHTLCState::AwaitingRemovedRemoteRevoke => {
                                                if htlc.fail_reason.is_none() {
                                                        value_to_self_msat_offset -= htlc.amount_msat as i64;
                                                }
                                        },
-                                       HTLCState::RemoteRemoved => {
+                                       OutboundHTLCState::RemoteRemoved => {
                                                if !generated_by_local && htlc.fail_reason.is_none() {
                                                        value_to_self_msat_offset -= htlc.amount_msat as i64;
                                                }
                                        },
-                                       HTLCState::LocalRemoved => {
-                                               if generated_by_local && htlc.local_removed_fulfilled {
-                                                       value_to_self_msat_offset += htlc.amount_msat as i64;
-                                               }
-                                       },
                                        _ => {},
                                }
                        }
@@ -820,7 +846,8 @@ impl Channel {
                        ins
                };
 
-               assert!(self.pending_htlcs.is_empty());
+               assert!(self.pending_inbound_htlcs.is_empty());
+               assert!(self.pending_outbound_htlcs.is_empty());
                let mut txouts: Vec<(TxOut, ())> = Vec::new();
 
                let mut total_fee_satoshis = proposed_total_fee_satoshis;
@@ -893,10 +920,11 @@ impl Channel {
 
        /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
        /// pays to get_funding_redeemscript().to_v0_p2wsh()).
+       /// Panics if called before accept_channel/new_from_req
        pub fn get_funding_redeemscript(&self) -> Script {
                let builder = Builder::new().push_opcode(opcodes::All::OP_PUSHNUM_2);
                let our_funding_key = PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.funding_key).serialize();
-               let their_funding_key = self.their_funding_pubkey.unwrap().serialize();
+               let their_funding_key = self.their_funding_pubkey.expect("get_funding_redeemscript only allowed after accept_channel").serialize();
                if our_funding_key[..] < their_funding_key[..] {
                        builder.push_slice(&our_funding_key)
                                .push_slice(&their_funding_key)
@@ -993,7 +1021,7 @@ impl Channel {
                Ok(our_sig)
        }
 
-       fn get_update_fulfill_htlc(&mut self, payment_preimage_arg: [u8; 32]) -> Result<(Option<msgs::UpdateFulfillHTLC>, Option<ChannelMonitor>), HandleError> {
+       fn get_update_fulfill_htlc(&mut self, htlc_id_arg: u64, payment_preimage_arg: [u8; 32]) -> Result<(Option<msgs::UpdateFulfillHTLC>, Option<ChannelMonitor>), HandleError> {
                // Either ChannelFunded got set (which means it wont bet unset) or there is no way any
                // caller thought we could have something claimed (cause we wouldn't have accepted in an
                // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
@@ -1009,20 +1037,17 @@ impl Channel {
                sha.result(&mut payment_hash_calc);
 
                let mut pending_idx = std::usize::MAX;
-               for (idx, htlc) in self.pending_htlcs.iter().enumerate() {
-                       if !htlc.outbound && htlc.payment_hash == payment_hash_calc &&
-                                       htlc.state != HTLCState::LocalRemoved {
-                               if let Some(PendingHTLCStatus::Fail(_)) = htlc.pending_forward_state {
-                               } else {
-                                       if pending_idx != std::usize::MAX {
-                                               panic!("Duplicate HTLC payment_hash, ChannelManager should have prevented this!");
-                                       }
+               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);
+                               if htlc.state != InboundHTLCState::LocalRemoved {
                                        pending_idx = idx;
+                                       break;
                                }
                        }
                }
                if pending_idx == std::usize::MAX {
-                       return Err(HandleError{err: "Unable to find a pending HTLC which matched the given payment preimage", action: None});
+                       return Err(HandleError{err: "Unable to find a pending HTLC which matched the given HTLC ID", action: None});
                }
 
                // Now update local state:
@@ -1034,31 +1059,31 @@ impl Channel {
                if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
                        for pending_update in self.holding_cell_htlc_updates.iter() {
                                match pending_update {
-                                       &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, .. } => {
-                                               if payment_preimage_arg == *payment_preimage {
+                                       &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
+                                               if htlc_id_arg == htlc_id {
                                                        return Ok((None, None));
                                                }
                                        },
-                                       &HTLCUpdateAwaitingACK::FailHTLC { ref payment_hash, .. } => {
-                                               if payment_hash_calc == *payment_hash {
-                                                       return Err(HandleError{err: "Unable to find a pending HTLC which matched the given payment preimage", action: None});
+                                       &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
+                                               if htlc_id_arg == htlc_id {
+                                                       return Err(HandleError{err: "Unable to find a pending HTLC which matched the given HTLC ID", action: None});
                                                }
                                        },
                                        _ => {}
                                }
                        }
                        self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
-                               payment_preimage: payment_preimage_arg, payment_hash: payment_hash_calc,
+                               payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
                        });
                        return Ok((None, Some(self.channel_monitor.clone())));
                }
 
-               let htlc_id = {
-                       let htlc = &mut self.pending_htlcs[pending_idx];
-                       if htlc.state == HTLCState::Committed {
-                               htlc.state = HTLCState::LocalRemoved;
+               {
+                       let htlc = &mut self.pending_inbound_htlcs[pending_idx];
+                       if htlc.state == InboundHTLCState::Committed {
+                               htlc.state = InboundHTLCState::LocalRemoved;
                                htlc.local_removed_fulfilled = true;
-                       } else if htlc.state == HTLCState::RemoteAnnounced || htlc.state == HTLCState::AwaitingRemoteRevokeToAnnounce || htlc.state == HTLCState::AwaitingAnnouncedRemoteRevoke {
+                       } else if htlc.state == InboundHTLCState::RemoteAnnounced || htlc.state == InboundHTLCState::AwaitingRemoteRevokeToAnnounce || htlc.state == InboundHTLCState::AwaitingAnnouncedRemoteRevoke {
                                // Theoretically we can hit this if we get the preimage on an HTLC prior to us
                                // having forwarded it to anyone. This implies that the sender is busted as someone
                                // else knows the preimage, but handling this case and implementing the logic to
@@ -1067,21 +1092,20 @@ impl Channel {
                                // channel_monitor and pretend we didn't just see the preimage.
                                return Ok((None, Some(self.channel_monitor.clone())));
                        } else {
-                               // LocalRemoved/LocalRemovedAwaitingCOmmitment handled in the search loop
+                               // LocalRemoved handled in the search loop
                                panic!("Have an inbound HTLC when not awaiting remote revoke that had a garbage state");
                        }
-                       htlc.htlc_id
-               };
+               }
 
                Ok((Some(msgs::UpdateFulfillHTLC {
                        channel_id: self.channel_id(),
-                       htlc_id: htlc_id,
+                       htlc_id: htlc_id_arg,
                        payment_preimage: payment_preimage_arg,
                }), Some(self.channel_monitor.clone())))
        }
 
-       pub fn get_update_fulfill_htlc_and_commit(&mut self, payment_preimage: [u8; 32]) -> Result<(Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>, Option<ChannelMonitor>), HandleError> {
-               match self.get_update_fulfill_htlc(payment_preimage)? {
+       pub fn get_update_fulfill_htlc_and_commit(&mut self, htlc_id: u64, payment_preimage: [u8; 32]) -> Result<(Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>, Option<ChannelMonitor>), HandleError> {
+               match self.get_update_fulfill_htlc(htlc_id, payment_preimage)? {
                        (Some(update_fulfill_htlc), _) => {
                                let (commitment, monitor_update) = self.send_commitment_no_status_check()?;
                                Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
@@ -1091,9 +1115,9 @@ impl Channel {
                }
        }
 
-       pub fn get_update_fail_htlc(&mut self, payment_hash_arg: &[u8; 32], err_packet: msgs::OnionErrorPacket) -> Result<Option<msgs::UpdateFailHTLC>, HandleError> {
+       pub fn get_update_fail_htlc(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket) -> Result<Option<msgs::UpdateFailHTLC>, HandleError> {
                if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
-                       return Err(HandleError{err: "Was asked to fail an HTLC when channel was not in an operational state", action: None});
+                       panic!("Was asked to fail an HTLC when channel was not in an operational state");
                }
                assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
 
@@ -1101,13 +1125,13 @@ impl Channel {
                if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
                        for pending_update in self.holding_cell_htlc_updates.iter() {
                                match pending_update {
-                                       &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_hash, .. } => {
-                                               if *payment_hash_arg == *payment_hash {
-                                                       return Err(HandleError{err: "Unable to find a pending HTLC which matched the given payment preimage", action: None});
+                                       &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
+                                               if htlc_id_arg == htlc_id {
+                                                       return Err(HandleError{err: "Unable to find a pending HTLC which matched the given HTLC ID", action: None});
                                                }
                                        },
-                                       &HTLCUpdateAwaitingACK::FailHTLC { ref payment_hash, .. } => {
-                                               if *payment_hash_arg == *payment_hash {
+                                       &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
+                                               if htlc_id_arg == htlc_id {
                                                        return Ok(None);
                                                }
                                        },
@@ -1115,52 +1139,40 @@ impl Channel {
                                }
                        }
                        self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
-                               payment_hash: payment_hash_arg.clone(),
+                               htlc_id: htlc_id_arg,
                                err_packet,
                        });
                        return Ok(None);
                }
 
-               let mut htlc_id = 0;
                let mut htlc_amount_msat = 0;
-               for htlc in self.pending_htlcs.iter_mut() {
-                       if !htlc.outbound && htlc.payment_hash == *payment_hash_arg {
-                               if htlc.state == HTLCState::Committed {
-                                       htlc.state = HTLCState::LocalRemoved;
-                               } else if htlc.state == HTLCState::RemoteAnnounced {
-                                       if let Some(PendingHTLCStatus::Forward(_)) = htlc.pending_forward_state {
-                                               panic!("Somehow forwarded HTLC prior to remote revocation!");
-                                       } else {
-                                               // We have to pretend this isn't here - we're probably a duplicate with the
-                                               // same payment_hash as some other HTLC, and the other is getting failed,
-                                               // we'll fail this one as soon as remote commits to it.
-                                               continue;
-                                       }
-                               } else if htlc.state == HTLCState::LocalRemoved {
-                                       return Err(HandleError{err: "Unable to find a pending HTLC which matched the given payment preimage", action: None});
+               for htlc in self.pending_inbound_htlcs.iter_mut() {
+                       if htlc.htlc_id == htlc_id_arg {
+                               if htlc.state == InboundHTLCState::Committed {
+                                       htlc.state = InboundHTLCState::LocalRemoved;
+                               } else if htlc.state == InboundHTLCState::RemoteAnnounced {
+                                       panic!("Somehow forwarded HTLC prior to remote revocation!");
+                               } else if htlc.state == InboundHTLCState::LocalRemoved {
+                                       return Err(HandleError{err: "Unable to find a pending HTLC which matched the given HTLC ID", action: None});
                                } else {
                                        panic!("Have an inbound HTLC when not awaiting remote revoke that had a garbage state");
                                }
-                               if htlc_id != 0 {
-                                       panic!("Duplicate HTLC payment_hash, you probably re-used payment preimages, NEVER DO THIS!");
-                               }
-                               htlc_id = htlc.htlc_id;
                                htlc_amount_msat += htlc.amount_msat;
                        }
                }
                if htlc_amount_msat == 0 {
-                       return Err(HandleError{err: "Unable to find a pending HTLC which matched the given payment preimage", action: None});
+                       return Err(HandleError{err: "Unable to find a pending HTLC which matched the given HTLC ID", action: None});
                }
 
                Ok(Some(msgs::UpdateFailHTLC {
                        channel_id: self.channel_id(),
-                       htlc_id,
+                       htlc_id: htlc_id_arg,
                        reason: err_packet
                }))
        }
 
-       pub fn get_update_fail_htlc_and_commit(&mut self, payment_hash: &[u8; 32], err_packet: msgs::OnionErrorPacket) -> Result<Option<(msgs::UpdateFailHTLC, msgs::CommitmentSigned, ChannelMonitor)>, HandleError> {
-               match self.get_update_fail_htlc(payment_hash, err_packet)? {
+       pub fn get_update_fail_htlc_and_commit(&mut self, htlc_id: u64, err_packet: msgs::OnionErrorPacket) -> Result<Option<(msgs::UpdateFailHTLC, msgs::CommitmentSigned, ChannelMonitor)>, HandleError> {
+               match self.get_update_fail_htlc(htlc_id, err_packet)? {
                        Some(update_fail_htlc) => {
                                let (commitment, monitor_update) = self.send_commitment_no_status_check()?;
                                Ok(Some((update_fail_htlc, commitment, monitor_update)))
@@ -1224,7 +1236,7 @@ impl Channel {
                // max_accepted_htlcs too small
                // dust_limit_satoshis too small
 
-               self.channel_monitor.set_their_htlc_base_key(&msg.htlc_basepoint);
+               self.channel_monitor.set_their_base_keys(&msg.htlc_basepoint, &msg.delayed_payment_basepoint);
 
                self.their_dust_limit_satoshis = msg.dust_limit_satoshis;
                self.their_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000);
@@ -1251,10 +1263,6 @@ impl Channel {
        fn funding_created_signature(&mut self, sig: &Signature) -> Result<(Transaction, Signature), HandleError> {
                let funding_script = self.get_funding_redeemscript();
 
-               let remote_keys = self.build_remote_transaction_keys()?;
-               let remote_initial_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, false).0;
-               let remote_sighash = Message::from_slice(&bip143::SighashComponents::new(&remote_initial_commitment_tx).sighash_all(&remote_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]).unwrap();
-
                let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?;
                let local_initial_commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false).0;
                let local_sighash = Message::from_slice(&bip143::SighashComponents::new(&local_initial_commitment_tx).sighash_all(&local_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]).unwrap();
@@ -1262,16 +1270,23 @@ impl Channel {
                // They sign the "local" commitment transaction, allowing us to broadcast the tx if we wish.
                secp_call!(self.secp_ctx.verify(&local_sighash, &sig, &self.their_funding_pubkey.unwrap()), "Invalid funding_created signature from peer", self.channel_id());
 
+               let remote_keys = self.build_remote_transaction_keys()?;
+               let remote_initial_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, false).0;
+               let remote_sighash = Message::from_slice(&bip143::SighashComponents::new(&remote_initial_commitment_tx).sighash_all(&remote_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]).unwrap();
+
                // We sign the "remote" commitment transaction, allowing them to broadcast the tx if they wish.
                Ok((remote_initial_commitment_tx, self.secp_ctx.sign(&remote_sighash, &self.local_keys.funding_key)))
        }
 
        pub fn funding_created(&mut self, msg: &msgs::FundingCreated) -> Result<(msgs::FundingSigned, ChannelMonitor), HandleError> {
                if self.channel_outbound {
-                       return Err(HandleError{err: "Received funding_created for an outbound channel?", action: None});
+                       return Err(HandleError{err: "Received funding_created for an outbound channel?", action: Some(msgs::ErrorAction::SendErrorMessage {msg: msgs::ErrorMessage {channel_id: self.channel_id, data: "Received funding_created for an outbound channel?".to_string()}})});
                }
                if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
-                       return Err(HandleError{err: "Received funding_created after we got the channel!", action: None});
+                       // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
+                       // remember the channel, so its safe to just send an error_message here and drop the
+                       // channel.
+                       return Err(HandleError{err: "Received funding_created after we got the channel!", action: Some(msgs::ErrorAction::SendErrorMessage {msg: msgs::ErrorMessage {channel_id: self.channel_id, data: "Received funding_created after we got the channel!".to_string()}})});
                }
                if self.channel_monitor.get_min_seen_secret() != (1 << 48) || self.cur_remote_commitment_transaction_number != (1 << 48) - 1 || self.cur_local_commitment_transaction_number != (1 << 48) - 1 {
                        panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
@@ -1357,30 +1372,34 @@ impl Channel {
        /// totals, though there is little reason to outside of further avoiding any race condition
        /// issues.
        fn get_pending_htlc_stats(&self, for_remote_update_check: bool) -> (u32, u32, u64, u64) {
+               //TODO: Can probably split this into inbound/outbound
                let mut inbound_htlc_count: u32 = 0;
                let mut outbound_htlc_count: u32 = 0;
                let mut htlc_outbound_value_msat = 0;
                let mut htlc_inbound_value_msat = 0;
-               for ref htlc in self.pending_htlcs.iter() {
+               for ref htlc in self.pending_inbound_htlcs.iter() {
                        match htlc.state {
-                               HTLCState::RemoteAnnounced => {},
-                               HTLCState::AwaitingRemoteRevokeToAnnounce => {},
-                               HTLCState::AwaitingAnnouncedRemoteRevoke => {},
-                               HTLCState::LocalAnnounced => { if for_remote_update_check { continue; } },
-                               HTLCState::Committed => {},
-                               HTLCState::RemoteRemoved => { if for_remote_update_check { continue; } },
-                               HTLCState::AwaitingRemoteRevokeToRemove => { if for_remote_update_check { continue; } },
-                               HTLCState::AwaitingRemovedRemoteRevoke => { if for_remote_update_check { continue; } },
-                               HTLCState::LocalRemoved => {},
+                               InboundHTLCState::RemoteAnnounced => {},
+                               InboundHTLCState::AwaitingRemoteRevokeToAnnounce => {},
+                               InboundHTLCState::AwaitingAnnouncedRemoteRevoke => {},
+                               InboundHTLCState::Committed => {},
+                               InboundHTLCState::LocalRemoved => {},
                        }
-                       if !htlc.outbound {
-                               inbound_htlc_count += 1;
-                               htlc_inbound_value_msat += htlc.amount_msat;
-                       } else {
-                               outbound_htlc_count += 1;
-                               htlc_outbound_value_msat += htlc.amount_msat;
+                       inbound_htlc_count += 1;
+                       htlc_inbound_value_msat += htlc.amount_msat;
+               }
+               for ref htlc in self.pending_outbound_htlcs.iter() {
+                       match htlc.state {
+                               OutboundHTLCState::LocalAnnounced => { if for_remote_update_check { continue; } },
+                               OutboundHTLCState::Committed => {},
+                               OutboundHTLCState::RemoteRemoved => { if for_remote_update_check { continue; } },
+                               OutboundHTLCState::AwaitingRemoteRevokeToRemove => { if for_remote_update_check { continue; } },
+                               OutboundHTLCState::AwaitingRemovedRemoteRevoke => { if for_remote_update_check { continue; } },
                        }
+                       outbound_htlc_count += 1;
+                       htlc_outbound_value_msat += htlc.amount_msat;
                }
+
                (inbound_htlc_count, outbound_htlc_count, htlc_outbound_value_msat, htlc_inbound_value_msat)
        }
 
@@ -1421,14 +1440,12 @@ impl Channel {
 
                // Now update local state:
                self.next_remote_htlc_id += 1;
-               self.pending_htlcs.push(HTLCOutput {
-                       outbound: false,
+               self.pending_inbound_htlcs.push(InboundHTLCOutput {
                        htlc_id: msg.htlc_id,
                        amount_msat: msg.amount_msat,
                        payment_hash: msg.payment_hash,
                        cltv_expiry: msg.cltv_expiry,
-                       state: HTLCState::RemoteAnnounced,
-                       fail_reason: None,
+                       state: InboundHTLCState::RemoteAnnounced,
                        local_removed_fulfilled: false,
                        pending_forward_state: Some(pending_forward_state),
                });
@@ -1438,9 +1455,9 @@ impl Channel {
 
        /// Removes an outbound HTLC which has been commitment_signed by the remote end
        #[inline]
-       fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<[u8; 32]>, fail_reason: Option<HTLCFailReason>) -> Result<[u8; 32], HandleError> {
-               for htlc in self.pending_htlcs.iter_mut() {
-                       if htlc.outbound && htlc.htlc_id == htlc_id {
+       fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<[u8; 32]>, fail_reason: Option<HTLCFailReason>) -> Result<&HTLCSource, HandleError> {
+               for htlc in self.pending_outbound_htlcs.iter_mut() {
+                       if htlc.htlc_id == htlc_id {
                                match check_preimage {
                                        None => {},
                                        Some(payment_hash) =>
@@ -1448,23 +1465,23 @@ impl Channel {
                                                        return Err(HandleError{err: "Remote tried to fulfill HTLC with an incorrect preimage", action: None});
                                                }
                                };
-                               if htlc.state == HTLCState::LocalAnnounced {
-                                       return Err(HandleError{err: "Remote tried to fulfill HTLC before it had been committed", action: None});
-                               } else if htlc.state == HTLCState::Committed {
-                                       htlc.state = HTLCState::RemoteRemoved;
-                                       htlc.fail_reason = fail_reason;
-                               } else if htlc.state == HTLCState::AwaitingRemoteRevokeToRemove || htlc.state == HTLCState::AwaitingRemovedRemoteRevoke || htlc.state == HTLCState::RemoteRemoved {
-                                       return Err(HandleError{err: "Remote tried to fulfill HTLC that they'd already fulfilled", action: None});
-                               } else {
-                                       panic!("Got a non-outbound state on an outbound HTLC");
+                               match htlc.state {
+                                       OutboundHTLCState::LocalAnnounced =>
+                                               return Err(HandleError{err: "Remote tried to fulfill HTLC before it had been committed", action: None}),
+                                       OutboundHTLCState::Committed => {
+                                               htlc.state = OutboundHTLCState::RemoteRemoved;
+                                               htlc.fail_reason = fail_reason;
+                                       },
+                                       OutboundHTLCState::AwaitingRemoteRevokeToRemove | OutboundHTLCState::AwaitingRemovedRemoteRevoke | OutboundHTLCState::RemoteRemoved =>
+                                               return Err(HandleError{err: "Remote tried to fulfill HTLC that they'd already fulfilled", action: None}),
                                }
-                               return Ok(htlc.payment_hash.clone());
+                               return Ok(&htlc.source);
                        }
                }
                Err(HandleError{err: "Remote tried to fulfill/fail an HTLC we couldn't find", action: None})
        }
 
-       pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<(), HandleError> {
+       pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<&HTLCSource, HandleError> {
                if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
                        return Err(HandleError{err: "Got add HTLC message when channel was not in an operational state", action: None});
                }
@@ -1474,11 +1491,10 @@ impl Channel {
                let mut payment_hash = [0; 32];
                sha.result(&mut payment_hash);
 
-               self.mark_outbound_htlc_removed(msg.htlc_id, Some(payment_hash), None)?;
-               Ok(())
+               self.mark_outbound_htlc_removed(msg.htlc_id, Some(payment_hash), None)
        }
 
-       pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<[u8; 32], HandleError> {
+       pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<&HTLCSource, HandleError> {
                if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
                        return Err(HandleError{err: "Got add HTLC message when channel was not in an operational state", action: None});
                }
@@ -1486,13 +1502,12 @@ impl Channel {
                self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))
        }
 
-       pub fn update_fail_malformed_htlc(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), HandleError> {
+       pub fn update_fail_malformed_htlc<'a>(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<&HTLCSource, HandleError> {
                if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
                        return Err(HandleError{err: "Got add HTLC message when channel was not in an operational state", action: None});
                }
 
-               self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
-               Ok(())
+               self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))
        }
 
        pub fn commitment_signed(&mut self, msg: &msgs::CommitmentSigned) -> Result<(msgs::RevokeAndACK, Option<msgs::CommitmentSigned>, ChannelMonitor), HandleError> {
@@ -1539,12 +1554,15 @@ impl Channel {
                self.channel_monitor.provide_latest_local_commitment_tx_info(local_commitment_tx.0, local_keys, self.feerate_per_kw, htlcs_and_sigs);
 
                let mut need_our_commitment = false;
-               for htlc in self.pending_htlcs.iter_mut() {
-                       if htlc.state == HTLCState::RemoteAnnounced {
-                               htlc.state = HTLCState::AwaitingRemoteRevokeToAnnounce;
+               for htlc in self.pending_inbound_htlcs.iter_mut() {
+                       if htlc.state == InboundHTLCState::RemoteAnnounced {
+                               htlc.state = InboundHTLCState::AwaitingRemoteRevokeToAnnounce;
                                need_our_commitment = true;
-                       } else if htlc.state == HTLCState::RemoteRemoved {
-                               htlc.state = HTLCState::AwaitingRemoteRevokeToRemove;
+                       }
+               }
+               for htlc in self.pending_outbound_htlcs.iter_mut() {
+                       if htlc.state == OutboundHTLCState::RemoteRemoved {
+                               htlc.state = OutboundHTLCState::AwaitingRemoteRevokeToRemove;
                                need_our_commitment = true;
                        }
                }
@@ -1587,24 +1605,24 @@ impl Channel {
                                        self.holding_cell_htlc_updates.push(htlc_update);
                                } else {
                                        match &htlc_update {
-                                               &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, payment_hash, ref onion_routing_packet, ..} => {
-                                                       match self.send_htlc(amount_msat, payment_hash, cltv_expiry, onion_routing_packet.clone()) {
+                                               &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, payment_hash, ref source, ref onion_routing_packet, ..} => {
+                                                       match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone()) {
                                                                Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()),
                                                                Err(e) => {
                                                                        err = Some(e);
                                                                }
                                                        }
                                                },
-                                               &HTLCUpdateAwaitingACK::ClaimHTLC { payment_preimage, .. } => {
-                                                       match self.get_update_fulfill_htlc(payment_preimage) {
+                                               &HTLCUpdateAwaitingACK::ClaimHTLC { payment_preimage, htlc_id, .. } => {
+                                                       match self.get_update_fulfill_htlc(htlc_id, payment_preimage) {
                                                                Ok(update_fulfill_msg_option) => update_fulfill_htlcs.push(update_fulfill_msg_option.0.unwrap()),
                                                                Err(e) => {
                                                                        err = Some(e);
                                                                }
                                                        }
                                                },
-                                               &HTLCUpdateAwaitingACK::FailHTLC { payment_hash, ref err_packet } => {
-                                                       match self.get_update_fail_htlc(&payment_hash, err_packet.clone()) {
+                                               &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
+                                                       match self.get_update_fail_htlc(htlc_id, err_packet.clone()) {
                                                                Ok(update_fail_msg_option) => update_fail_htlcs.push(update_fail_msg_option.unwrap()),
                                                                Err(e) => {
                                                                        err = Some(e);
@@ -1642,7 +1660,7 @@ impl Channel {
        /// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail,
        /// generating an appropriate error *after* the channel state has been updated based on the
        /// revoke_and_ack message.
-       pub fn revoke_and_ack(&mut self, msg: &msgs::RevokeAndACK) -> Result<(Option<msgs::CommitmentUpdate>, Vec<PendingForwardHTLCInfo>, Vec<([u8; 32], HTLCFailReason)>, ChannelMonitor), HandleError> {
+       pub fn revoke_and_ack(&mut self, msg: &msgs::RevokeAndACK) -> Result<(Option<msgs::CommitmentUpdate>, Vec<(PendingForwardHTLCInfo, u64)>, Vec<(HTLCSource, [u8; 32], HTLCFailReason)>, ChannelMonitor), HandleError> {
                if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
                        return Err(HandleError{err: "Got revoke/ACK message when channel was not in an operational state", action: None});
                }
@@ -1669,15 +1687,18 @@ impl Channel {
                let mut require_commitment = false;
                let mut value_to_self_msat_diff: i64 = 0;
                // We really shouldnt have two passes here, but retain gives a non-mutable ref (Rust bug)
-               self.pending_htlcs.retain(|htlc| {
-                       if htlc.state == HTLCState::LocalRemoved {
+               self.pending_inbound_htlcs.retain(|htlc| {
+                       if htlc.state == InboundHTLCState::LocalRemoved {
                                if htlc.local_removed_fulfilled {
                                        value_to_self_msat_diff += htlc.amount_msat as i64;
                                }
                                false
-                       } else if htlc.state == HTLCState::AwaitingRemovedRemoteRevoke {
+                       } else { true }
+               });
+               self.pending_outbound_htlcs.retain(|htlc| {
+                       if htlc.state == OutboundHTLCState::AwaitingRemovedRemoteRevoke {
                                if let Some(reason) = htlc.fail_reason.clone() { // We really want take() here, but, again, non-mut ref :(
-                                       revoked_htlcs.push((htlc.payment_hash, reason));
+                                       revoked_htlcs.push((htlc.source.clone(), htlc.payment_hash, reason));
                                } else {
                                        // They fulfilled, so we sent them money
                                        value_to_self_msat_diff -= htlc.amount_msat as i64;
@@ -1685,16 +1706,14 @@ impl Channel {
                                false
                        } else { true }
                });
-               for htlc in self.pending_htlcs.iter_mut() {
-                       if htlc.state == HTLCState::LocalAnnounced {
-                               htlc.state = HTLCState::Committed;
-                       } else if htlc.state == HTLCState::AwaitingRemoteRevokeToAnnounce {
-                               htlc.state = HTLCState::AwaitingAnnouncedRemoteRevoke;
+               for htlc in self.pending_inbound_htlcs.iter_mut() {
+                       if htlc.state == InboundHTLCState::AwaitingRemoteRevokeToAnnounce {
+                               htlc.state = InboundHTLCState::AwaitingAnnouncedRemoteRevoke;
                                require_commitment = true;
-                       } else if htlc.state == HTLCState::AwaitingAnnouncedRemoteRevoke {
+                       } else if htlc.state == InboundHTLCState::AwaitingAnnouncedRemoteRevoke {
                                match htlc.pending_forward_state.take().unwrap() {
                                        PendingHTLCStatus::Fail(fail_msg) => {
-                                               htlc.state = HTLCState::LocalRemoved;
+                                               htlc.state = InboundHTLCState::LocalRemoved;
                                                require_commitment = true;
                                                match fail_msg {
                                                        HTLCFailureMsg::Relay(msg) => update_fail_htlcs.push(msg),
@@ -1702,12 +1721,17 @@ impl Channel {
                                                }
                                        },
                                        PendingHTLCStatus::Forward(forward_info) => {
-                                               to_forward_infos.push(forward_info);
-                                               htlc.state = HTLCState::Committed;
+                                               to_forward_infos.push((forward_info, htlc.htlc_id));
+                                               htlc.state = InboundHTLCState::Committed;
                                        }
                                }
-                       } else if htlc.state == HTLCState::AwaitingRemoteRevokeToRemove {
-                               htlc.state = HTLCState::AwaitingRemovedRemoteRevoke;
+                       }
+               }
+               for htlc in self.pending_outbound_htlcs.iter_mut() {
+                       if htlc.state == OutboundHTLCState::LocalAnnounced {
+                               htlc.state = OutboundHTLCState::Committed;
+                       } else if htlc.state == OutboundHTLCState::AwaitingRemoteRevokeToRemove {
+                               htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke;
                                require_commitment = true;
                        }
                }
@@ -1752,14 +1776,14 @@ impl Channel {
                Ok(())
        }
 
-       pub fn shutdown(&mut self, fee_estimator: &FeeEstimator, msg: &msgs::Shutdown) -> Result<(Option<msgs::Shutdown>, Option<msgs::ClosingSigned>, Vec<[u8; 32]>), HandleError> {
+       pub fn shutdown(&mut self, fee_estimator: &FeeEstimator, msg: &msgs::Shutdown) -> Result<(Option<msgs::Shutdown>, Option<msgs::ClosingSigned>, Vec<(HTLCSource, [u8; 32])>), HandleError> {
                if self.channel_state < ChannelState::FundingSent as u32 {
                        self.channel_state = ChannelState::ShutdownComplete as u32;
                        self.channel_update_count += 1;
                        return Ok((None, None, Vec::new()));
                }
-               for htlc in self.pending_htlcs.iter() {
-                       if htlc.state == HTLCState::RemoteAnnounced {
+               for htlc in self.pending_inbound_htlcs.iter() {
+                       if htlc.state == InboundHTLCState::RemoteAnnounced {
                                return Err(HandleError{err: "Got shutdown with remote pending HTLCs", action: None});
                        }
                }
@@ -1785,7 +1809,7 @@ impl Channel {
 
                let our_closing_script = self.get_closing_scriptpubkey();
 
-               let (proposed_feerate, proposed_fee, our_sig) = if self.channel_outbound && self.pending_htlcs.is_empty() {
+               let (proposed_feerate, proposed_fee, our_sig) = if self.channel_outbound && self.pending_inbound_htlcs.is_empty() && self.pending_outbound_htlcs.is_empty() {
                        let mut proposed_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
                        if self.feerate_per_kw > proposed_feerate {
                                proposed_feerate = self.feerate_per_kw;
@@ -1811,15 +1835,15 @@ impl Channel {
                let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
                self.holding_cell_htlc_updates.retain(|htlc_update| {
                        match htlc_update {
-                               &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, .. } => {
-                                       dropped_outbound_htlcs.push(payment_hash.clone());
+                               &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
+                                       dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
                                        false
                                },
                                _ => true
                        }
                });
-               for htlc in self.pending_htlcs.iter() {
-                       if htlc.state == HTLCState::LocalAnnounced {
+               for htlc in self.pending_outbound_htlcs.iter() {
+                       if htlc.state == OutboundHTLCState::LocalAnnounced {
                                return Ok((None, None, dropped_outbound_htlcs));
                        }
                }
@@ -1835,7 +1859,7 @@ impl Channel {
 
                self.channel_state |= ChannelState::LocalShutdownSent as u32;
                self.channel_update_count += 1;
-               if self.pending_htlcs.is_empty() && self.channel_outbound {
+               if self.pending_inbound_htlcs.is_empty() && self.pending_outbound_htlcs.is_empty() && self.channel_outbound {
                        // There are no more HTLCs and we're the funder, this means we start the closing_signed
                        // dance with an initial fee proposal!
                        self.last_sent_closing_fee = Some((proposed_feerate.unwrap(), proposed_fee.unwrap()));
@@ -1853,7 +1877,7 @@ impl Channel {
                if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK {
                        return Err(HandleError{err: "Remote end sent us a closing_signed before both sides provided a shutdown", action: None});
                }
-               if !self.pending_htlcs.is_empty() {
+               if !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() {
                        return Err(HandleError{err: "Remote end sent us a closing_signed while there were still pending HTLCs", action: None});
                }
                if msg.fee_satoshis > 21000000 * 10000000 {
@@ -2317,7 +2341,7 @@ impl Channel {
        /// 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
-       pub fn send_htlc(&mut self, amount_msat: u64, payment_hash: [u8; 32], cltv_expiry: u32, onion_routing_packet: msgs::OnionPacket) -> Result<Option<msgs::UpdateAddHTLC>, HandleError> {
+       pub fn send_htlc(&mut self, amount_msat: u64, payment_hash: [u8; 32], cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result<Option<msgs::UpdateAddHTLC>, HandleError> {
                if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
                        return Err(HandleError{err: "Cannot send HTLC until channel is fully established and we haven't started shutting down", action: None});
                }
@@ -2352,22 +2376,21 @@ impl Channel {
                                amount_msat: amount_msat,
                                payment_hash: payment_hash,
                                cltv_expiry: cltv_expiry,
+                               source,
                                onion_routing_packet: onion_routing_packet,
                                time_created: Instant::now(),
                        });
                        return Ok(None);
                }
 
-               self.pending_htlcs.push(HTLCOutput {
-                       outbound: true,
+               self.pending_outbound_htlcs.push(OutboundHTLCOutput {
                        htlc_id: self.next_local_htlc_id,
                        amount_msat: amount_msat,
                        payment_hash: payment_hash.clone(),
                        cltv_expiry: cltv_expiry,
-                       state: HTLCState::LocalAnnounced,
+                       state: OutboundHTLCState::LocalAnnounced,
+                       source,
                        fail_reason: None,
-                       local_removed_fulfilled: false,
-                       pending_forward_state: None
                });
 
                let res = msgs::UpdateAddHTLC {
@@ -2386,22 +2409,23 @@ impl Channel {
        /// Creates a signed commitment transaction to send to the remote peer.
        /// Always returns a Channel-failing HandleError::action if an immediately-preceding (read: the
        /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
+       /// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc.
        pub fn send_commitment(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitor), HandleError> {
                if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
-                       return Err(HandleError{err: "Cannot create commitment tx until channel is fully established", action: None});
+                       panic!("Cannot create commitment tx until channel is fully established");
                }
                if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
-                       return Err(HandleError{err: "Cannot create commitment tx until remote revokes their previous commitment", action: None});
+                       panic!("Cannot create commitment tx until remote revokes their previous commitment");
                }
                let mut have_updates = false; // TODO initialize with "have we sent a fee update?"
-               for htlc in self.pending_htlcs.iter() {
-                       if htlc.state == HTLCState::LocalAnnounced {
+               for htlc in self.pending_outbound_htlcs.iter() {
+                       if htlc.state == OutboundHTLCState::LocalAnnounced {
                                have_updates = true;
                        }
                        if have_updates { break; }
                }
                if !have_updates {
-                       return Err(HandleError{err: "Cannot create commitment tx until we have some updates to send", action: None});
+                       panic!("Cannot create commitment tx until we have some updates to send");
                }
                self.send_commitment_no_status_check()
        }
@@ -2412,11 +2436,14 @@ impl Channel {
                // We can upgrade the status of some HTLCs that are waiting on a commitment, even if we
                // fail to generate this, we still are at least at a position where upgrading their status
                // is acceptable.
-               for htlc in self.pending_htlcs.iter_mut() {
-                       if htlc.state == HTLCState::AwaitingRemoteRevokeToAnnounce {
-                               htlc.state = HTLCState::AwaitingAnnouncedRemoteRevoke;
-                       } else if htlc.state == HTLCState::AwaitingRemoteRevokeToRemove {
-                               htlc.state = HTLCState::AwaitingRemovedRemoteRevoke;
+               for htlc in self.pending_inbound_htlcs.iter_mut() {
+                       if htlc.state == InboundHTLCState::AwaitingRemoteRevokeToAnnounce {
+                               htlc.state = InboundHTLCState::AwaitingAnnouncedRemoteRevoke;
+                       }
+               }
+               for htlc in self.pending_outbound_htlcs.iter_mut() {
+                       if htlc.state == OutboundHTLCState::AwaitingRemoteRevokeToRemove {
+                               htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke;
                        }
                }
 
@@ -2451,8 +2478,8 @@ impl Channel {
        /// to send to the remote peer in one go.
        /// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
        /// more info.
-       pub fn send_htlc_and_commit(&mut self, amount_msat: u64, payment_hash: [u8; 32], cltv_expiry: u32, onion_routing_packet: msgs::OnionPacket) -> Result<Option<(msgs::UpdateAddHTLC, msgs::CommitmentSigned, ChannelMonitor)>, HandleError> {
-               match self.send_htlc(amount_msat, payment_hash, cltv_expiry, onion_routing_packet)? {
+       pub fn send_htlc_and_commit(&mut self, amount_msat: u64, payment_hash: [u8; 32], cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result<Option<(msgs::UpdateAddHTLC, msgs::CommitmentSigned, ChannelMonitor)>, HandleError> {
+               match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet)? {
                        Some(update_add_htlc) => {
                                let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
                                Ok(Some((update_add_htlc, commitment_signed, monitor_update)))
@@ -2463,9 +2490,9 @@ impl Channel {
 
        /// 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<[u8; 32]>), HandleError> {
-               for htlc in self.pending_htlcs.iter() {
-                       if htlc.state == HTLCState::LocalAnnounced {
+       pub fn get_shutdown(&mut self) -> Result<(msgs::Shutdown, Vec<(HTLCSource, [u8; 32])>), HandleError> {
+               for htlc in self.pending_outbound_htlcs.iter() {
+                       if htlc.state == OutboundHTLCState::LocalAnnounced {
                                return Err(HandleError{err: "Cannot begin shutdown with pending HTLCs, call send_commitment first", action: None});
                        }
                }
@@ -2490,8 +2517,8 @@ impl Channel {
                let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
                self.holding_cell_htlc_updates.retain(|htlc_update| {
                        match htlc_update {
-                               &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, .. } => {
-                                       dropped_outbound_htlcs.push(payment_hash.clone());
+                               &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
+                                       dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
                                        false
                                },
                                _ => true
@@ -2509,7 +2536,7 @@ impl Channel {
        /// 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) -> (Vec<Transaction>, Vec<[u8; 32]>) {
+       pub fn force_shutdown(&mut self) -> (Vec<Transaction>, Vec<(HTLCSource, [u8; 32])>) {
                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
@@ -2517,16 +2544,16 @@ impl Channel {
                let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
                for htlc_update in self.holding_cell_htlc_updates.drain(..) {
                        match htlc_update {
-                               HTLCUpdateAwaitingACK::AddHTLC { payment_hash, .. } => {
-                                       dropped_outbound_htlcs.push(payment_hash);
+                               HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
+                                       dropped_outbound_htlcs.push((source, payment_hash));
                                },
                                _ => {}
                        }
                }
 
-               for htlc in self.pending_htlcs.drain(..) {
-                       if htlc.state == HTLCState::LocalAnnounced {
-                               dropped_outbound_htlcs.push(htlc.payment_hash);
+               for htlc in self.pending_outbound_htlcs.drain(..) {
+                       if htlc.state == OutboundHTLCState::LocalAnnounced {
+                               dropped_outbound_htlcs.push((htlc.source, htlc.payment_hash));
                        }
                        //TODO: Do something with the remaining HTLCs
                        //(we need to have the ChannelManager monitor them so we can claim the inbound HTLCs
@@ -2549,7 +2576,8 @@ mod tests {
        use bitcoin::blockdata::script::Script;
        use bitcoin::blockdata::transaction::Transaction;
        use hex;
-       use ln::channel::{Channel,ChannelKeys,HTLCOutput,HTLCState,HTLCOutputInCommitment,TxCreationKeys};
+       use ln::channelmanager::HTLCSource;
+       use ln::channel::{Channel,ChannelKeys,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,TxCreationKeys};
        use ln::channel::MAX_FUNDING_SATOSHIS;
        use ln::chan_utils;
        use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
@@ -2688,15 +2716,13 @@ mod tests {
                                         "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");
                }
 
-               chan.pending_htlcs.push({
-                       let mut out = HTLCOutput{
+               chan.pending_inbound_htlcs.push({
+                       let mut out = InboundHTLCOutput{
                                htlc_id: 0,
-                               outbound: false,
                                amount_msat: 1000000,
                                cltv_expiry: 500,
                                payment_hash: [0; 32],
-                               state: HTLCState::Committed,
-                               fail_reason: None,
+                               state: InboundHTLCState::Committed,
                                local_removed_fulfilled: false,
                                pending_forward_state: None,
                        };
@@ -2705,15 +2731,13 @@ mod tests {
                        sha.result(&mut out.payment_hash);
                        out
                });
-               chan.pending_htlcs.push({
-                       let mut out = HTLCOutput{
+               chan.pending_inbound_htlcs.push({
+                       let mut out = InboundHTLCOutput{
                                htlc_id: 1,
-                               outbound: false,
                                amount_msat: 2000000,
                                cltv_expiry: 501,
                                payment_hash: [0; 32],
-                               state: HTLCState::Committed,
-                               fail_reason: None,
+                               state: InboundHTLCState::Committed,
                                local_removed_fulfilled: false,
                                pending_forward_state: None,
                        };
@@ -2722,49 +2746,43 @@ mod tests {
                        sha.result(&mut out.payment_hash);
                        out
                });
-               chan.pending_htlcs.push({
-                       let mut out = HTLCOutput{
+               chan.pending_outbound_htlcs.push({
+                       let mut out = OutboundHTLCOutput{
                                htlc_id: 2,
-                               outbound: true,
                                amount_msat: 2000000,
                                cltv_expiry: 502,
                                payment_hash: [0; 32],
-                               state: HTLCState::Committed,
+                               state: OutboundHTLCState::Committed,
+                               source: HTLCSource::dummy(),
                                fail_reason: None,
-                               local_removed_fulfilled: false,
-                               pending_forward_state: None,
                        };
                        let mut sha = Sha256::new();
                        sha.input(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap());
                        sha.result(&mut out.payment_hash);
                        out
                });
-               chan.pending_htlcs.push({
-                       let mut out = HTLCOutput{
+               chan.pending_outbound_htlcs.push({
+                       let mut out = OutboundHTLCOutput{
                                htlc_id: 3,
-                               outbound: true,
                                amount_msat: 3000000,
                                cltv_expiry: 503,
                                payment_hash: [0; 32],
-                               state: HTLCState::Committed,
+                               state: OutboundHTLCState::Committed,
+                               source: HTLCSource::dummy(),
                                fail_reason: None,
-                               local_removed_fulfilled: false,
-                               pending_forward_state: None,
                        };
                        let mut sha = Sha256::new();
                        sha.input(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap());
                        sha.result(&mut out.payment_hash);
                        out
                });
-               chan.pending_htlcs.push({
-                       let mut out = HTLCOutput{
+               chan.pending_inbound_htlcs.push({
+                       let mut out = InboundHTLCOutput{
                                htlc_id: 4,
-                               outbound: false,
                                amount_msat: 4000000,
                                cltv_expiry: 504,
                                payment_hash: [0; 32],
-                               state: HTLCState::Committed,
-                               fail_reason: None,
+                               state: InboundHTLCState::Committed,
                                local_removed_fulfilled: false,
                                pending_forward_state: None,
                        };