Merge pull request #127 from TheBlueMatt/2018-08-fuzz-fixes-5
[rust-lightning] / src / ln / channelmanager.rs
index 73b4ecca304ae1676bf231d8f28f6c2c10079170..20e6f3739ec63ee3eee62715cd21bb8a21f4805e 100644 (file)
@@ -40,6 +40,7 @@ mod channel_held_info {
        use ln::msgs;
 
        /// Stores the info we will need to send when we want to forward an HTLC onwards
+       #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
        pub struct PendingForwardHTLCInfo {
                pub(super) onion_packet: Option<msgs::OnionPacket>,
                pub(super) payment_hash: [u8; 32],
@@ -49,17 +50,24 @@ mod channel_held_info {
                pub(super) outgoing_cltv_value: u32,
        }
 
+       /// Stores whether we can't forward an HTLC or relevant forwarding info
+       #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
+       pub enum PendingHTLCStatus {
+               Forward(PendingForwardHTLCInfo),
+               Fail(msgs::UpdateFailHTLC),
+       }
+
        #[cfg(feature = "fuzztarget")]
-       impl PendingForwardHTLCInfo {
+       impl PendingHTLCStatus {
                pub fn dummy() -> Self {
-                       Self {
+                       PendingHTLCStatus::Forward(PendingForwardHTLCInfo {
                                onion_packet: None,
                                payment_hash: [0; 32],
                                short_channel_id: 0,
                                prev_short_channel_id: 0,
                                amt_to_forward: 0,
                                outgoing_cltv_value: 0,
-                       }
+                       })
                }
        }
 
@@ -162,7 +170,7 @@ pub struct ChannelManager {
        announce_channels_publicly: bool,
        fee_proportional_millionths: u32,
        latest_block_height: AtomicUsize,
-       secp_ctx: Secp256k1,
+       secp_ctx: Secp256k1<secp256k1::All>,
 
        channel_state: Mutex<ChannelHolder>,
        our_network_key: SecretKey,
@@ -461,9 +469,9 @@ impl ChannelManager {
 
        // can only fail if an intermediary hop has an invalid public key or session_priv is invalid
        #[inline]
-       fn construct_onion_keys_callback<FType: FnMut(SharedSecret, [u8; 32], PublicKey, &RouteHop)> (secp_ctx: &Secp256k1, route: &Route, session_priv: &SecretKey, mut callback: FType) -> Result<(), HandleError> {
+       fn construct_onion_keys_callback<T: secp256k1::Signing, FType: FnMut(SharedSecret, [u8; 32], PublicKey, &RouteHop)> (secp_ctx: &Secp256k1<T>, route: &Route, session_priv: &SecretKey, mut callback: FType) -> Result<(), HandleError> {
                let mut blinded_priv = session_priv.clone();
-               let mut blinded_pub = secp_call!(PublicKey::from_secret_key(secp_ctx, &blinded_priv));
+               let mut blinded_pub = PublicKey::from_secret_key(secp_ctx, &blinded_priv);
                let mut first_iteration = true;
 
                for hop in route.hops.iter() {
@@ -476,13 +484,13 @@ impl ChannelManager {
                        sha.result(&mut blinding_factor);
 
                        if first_iteration {
-                               blinded_pub = secp_call!(PublicKey::from_secret_key(secp_ctx, &blinded_priv));
+                               blinded_pub = PublicKey::from_secret_key(secp_ctx, &blinded_priv);
                                first_iteration = false;
                        }
                        let ephemeral_pubkey = blinded_pub;
 
                        secp_call!(blinded_priv.mul_assign(secp_ctx, &secp_call!(SecretKey::from_slice(secp_ctx, &blinding_factor))));
-                       blinded_pub = secp_call!(PublicKey::from_secret_key(secp_ctx, &blinded_priv));
+                       blinded_pub = PublicKey::from_secret_key(secp_ctx, &blinded_priv);
 
                        callback(shared_secret, blinding_factor, ephemeral_pubkey, hop);
                }
@@ -491,7 +499,7 @@ impl ChannelManager {
        }
 
        // can only fail if an intermediary hop has an invalid public key or session_priv is invalid
-       fn construct_onion_keys(secp_ctx: &Secp256k1, route: &Route, session_priv: &SecretKey) -> Result<Vec<OnionKeys>, HandleError> {
+       fn construct_onion_keys<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, route: &Route, session_priv: &SecretKey) -> Result<Vec<OnionKeys>, HandleError> {
                let mut res = Vec::with_capacity(route.hops.len());
 
                Self::construct_onion_keys_callback(secp_ctx, route, session_priv, |shared_secret, _blinding_factor, ephemeral_pubkey, _| {
@@ -667,6 +675,180 @@ impl ChannelManager {
                ChannelManager::encrypt_failure_packet(shared_secret, &failure_packet.encode()[..])
        }
 
+       fn decode_update_add_htlc_onion(&self, msg: &msgs::UpdateAddHTLC) -> (PendingHTLCStatus, SharedSecret, MutexGuard<ChannelHolder>) {
+               let shared_secret = SharedSecret::new(&self.secp_ctx, &msg.onion_routing_packet.public_key, &self.our_network_key);
+               let (rho, mu) = ChannelManager::gen_rho_mu_from_shared_secret(&shared_secret);
+
+               macro_rules! get_onion_hash {
+                       () => {
+                               {
+                                       let mut sha = Sha256::new();
+                                       sha.input(&msg.onion_routing_packet.hop_data);
+                                       let mut onion_hash = [0; 32];
+                                       sha.result(&mut onion_hash);
+                                       onion_hash
+                               }
+                       }
+               }
+
+               let mut channel_state = None;
+               macro_rules! return_err {
+                       ($msg: expr, $err_code: expr, $data: expr) => {
+                               {
+                                       log_info!(self, "Failed to accept/forward incoming HTLC: {}", $msg);
+                                       if channel_state.is_none() {
+                                               channel_state = Some(self.channel_state.lock().unwrap());
+                                       }
+                                       return (PendingHTLCStatus::Fail(msgs::UpdateFailHTLC {
+                                               channel_id: msg.channel_id,
+                                               htlc_id: msg.htlc_id,
+                                               reason: ChannelManager::build_first_hop_failure_packet(&shared_secret, $err_code, $data),
+                                       }), shared_secret, channel_state.unwrap());
+                               }
+                       }
+               }
+
+               if msg.onion_routing_packet.version != 0 {
+                       //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
+                       //sha256_of_onion error data packets), or the entire onion_routing_packet. Either way,
+                       //the hash doesn't really serve any purpuse - in the case of hashing all data, the
+                       //receiving node would have to brute force to figure out which version was put in the
+                       //packet by the node that send us the message, in the case of hashing the hop_data, the
+                       //node knows the HMAC matched, so they already know what is there...
+                       return_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4, &get_onion_hash!());
+               }
+
+               let mut hmac = Hmac::new(Sha256::new(), &mu);
+               hmac.input(&msg.onion_routing_packet.hop_data);
+               hmac.input(&msg.payment_hash);
+               if hmac.result() != MacResult::new(&msg.onion_routing_packet.hmac) {
+                       return_err!("HMAC Check failed", 0x8000 | 0x4000 | 5, &get_onion_hash!());
+               }
+
+               let mut chacha = ChaCha20::new(&rho, &[0u8; 8]);
+               let next_hop_data = {
+                       let mut decoded = [0; 65];
+                       chacha.process(&msg.onion_routing_packet.hop_data[0..65], &mut decoded);
+                       match msgs::OnionHopData::decode(&decoded[..]) {
+                               Err(err) => {
+                                       let error_code = match err {
+                                               msgs::DecodeError::UnknownRealmByte => 0x4000 | 1,
+                                               _ => 0x2000 | 2, // Should never happen
+                                       };
+                                       return_err!("Unable to decode our hop data", error_code, &[0;0]);
+                               },
+                               Ok(msg) => msg
+                       }
+               };
+
+               //TODO: Check that msg.cltv_expiry is within acceptable bounds!
+
+               let pending_forward_info = if next_hop_data.hmac == [0; 32] {
+                               // OUR PAYMENT!
+                               if next_hop_data.data.amt_to_forward != msg.amount_msat {
+                                       return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat));
+                               }
+                               if next_hop_data.data.outgoing_cltv_value != msg.cltv_expiry {
+                                       return_err!("Upstream node set CLTV to the wrong value", 18, &byte_utils::be32_to_array(msg.cltv_expiry));
+                               }
+
+                               // Note that we could obviously respond immediately with an update_fulfill_htlc
+                               // message, however that would leak that we are the recipient of this payment, so
+                               // instead we stay symmetric with the forwarding case, only responding (after a
+                               // delay) once they've send us a commitment_signed!
+
+                               PendingHTLCStatus::Forward(PendingForwardHTLCInfo {
+                                       onion_packet: None,
+                                       payment_hash: msg.payment_hash.clone(),
+                                       short_channel_id: 0,
+                                       prev_short_channel_id: 0,
+                                       amt_to_forward: next_hop_data.data.amt_to_forward,
+                                       outgoing_cltv_value: next_hop_data.data.outgoing_cltv_value,
+                               })
+                       } else {
+                               let mut new_packet_data = [0; 20*65];
+                               chacha.process(&msg.onion_routing_packet.hop_data[65..], &mut new_packet_data[0..19*65]);
+                               chacha.process(&ChannelManager::ZERO[0..65], &mut new_packet_data[19*65..]);
+
+                               let mut new_pubkey = msg.onion_routing_packet.public_key.clone();
+
+                               let blinding_factor = {
+                                       let mut sha = Sha256::new();
+                                       sha.input(&new_pubkey.serialize()[..]);
+                                       sha.input(&shared_secret[..]);
+                                       let mut res = [0u8; 32];
+                                       sha.result(&mut res);
+                                       match SecretKey::from_slice(&self.secp_ctx, &res) {
+                                               Err(_) => {
+                                                       // Return temporary node failure as its technically our issue, not the
+                                                       // channel's issue.
+                                                       return_err!("Blinding factor is an invalid private key", 0x2000 | 2, &[0;0]);
+                                               },
+                                               Ok(key) => key
+                                       }
+                               };
+
+                               match new_pubkey.mul_assign(&self.secp_ctx, &blinding_factor) {
+                                       Err(_) => {
+                                               // Return temporary node failure as its technically our issue, not the
+                                               // channel's issue.
+                                               return_err!("New blinding factor is an invalid private key", 0x2000 | 2, &[0;0]);
+                                       },
+                                       Ok(_) => {}
+                               };
+
+                               let outgoing_packet = msgs::OnionPacket {
+                                       version: 0,
+                                       public_key: new_pubkey,
+                                       hop_data: new_packet_data,
+                                       hmac: next_hop_data.hmac.clone(),
+                               };
+
+                               PendingHTLCStatus::Forward(PendingForwardHTLCInfo {
+                                       onion_packet: Some(outgoing_packet),
+                                       payment_hash: msg.payment_hash.clone(),
+                                       short_channel_id: next_hop_data.data.short_channel_id,
+                                       prev_short_channel_id: 0,
+                                       amt_to_forward: next_hop_data.data.amt_to_forward,
+                                       outgoing_cltv_value: next_hop_data.data.outgoing_cltv_value,
+                               })
+                       };
+
+               channel_state = Some(self.channel_state.lock().unwrap());
+               if let &PendingHTLCStatus::Forward(PendingForwardHTLCInfo { ref onion_packet, ref short_channel_id, ref amt_to_forward, ref outgoing_cltv_value, .. }) = &pending_forward_info {
+                       if onion_packet.is_some() { // If short_channel_id is 0 here, we'll reject them in the body here
+                               let id_option = channel_state.as_ref().unwrap().short_to_id.get(&short_channel_id).cloned();
+                               let forwarding_id = match id_option {
+                                       None => {
+                                               return_err!("Don't have available channel for forwarding as requested.", 0x4000 | 10, &[0;0]);
+                                       },
+                                       Some(id) => id.clone(),
+                               };
+                               if let Some((err, code, chan_update)) = {
+                                       let chan = channel_state.as_mut().unwrap().by_id.get_mut(&forwarding_id).unwrap();
+                                       if !chan.is_live() {
+                                               Some(("Forwarding channel is not in a ready state.", 0x1000 | 7, self.get_channel_update(chan).unwrap()))
+                                       } else {
+                                               let fee = amt_to_forward.checked_mul(self.fee_proportional_millionths as u64).and_then(|prop_fee| { (prop_fee / 1000000).checked_add(chan.get_our_fee_base_msat(&*self.fee_estimator) as u64) });
+                                               if fee.is_none() || msg.amount_msat < fee.unwrap() || (msg.amount_msat - fee.unwrap()) < *amt_to_forward {
+                                                       Some(("Prior hop has deviated from specified fees parameters or origin node has obsolete ones", 0x1000 | 12, self.get_channel_update(chan).unwrap()))
+                                               } else {
+                                                       if (msg.cltv_expiry as u64) < (*outgoing_cltv_value) as u64 + CLTV_EXPIRY_DELTA as u64 {
+                                                               Some(("Forwarding node has tampered with the intended HTLC values or origin node has an obsolete cltv_expiry_delta", 0x1000 | 13, self.get_channel_update(chan).unwrap()))
+                                                       } else {
+                                                               None
+                                                       }
+                                               }
+                                       }
+                               } {
+                                       return_err!(err, code, &chan_update.encode_with_len()[..]);
+                               }
+                       }
+               }
+
+               (pending_forward_info, shared_secret, channel_state.unwrap())
+       }
+
        /// only fails if the channel does not yet have an assigned short_id
        fn get_channel_update(&self, chan: &Channel) -> Result<msgs::ChannelUpdate, HandleError> {
                let short_channel_id = match chan.get_short_channel_id() {
@@ -674,7 +856,7 @@ impl ChannelManager {
                        Some(id) => id,
                };
 
-               let were_node_one = PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).unwrap().serialize()[..] < chan.get_their_node_id().serialize()[..];
+               let were_node_one = PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).serialize()[..] < chan.get_their_node_id().serialize()[..];
 
                let unsigned = msgs::UnsignedChannelUpdate {
                        chain_hash: self.genesis_hash,
@@ -688,7 +870,7 @@ impl ChannelManager {
                };
 
                let msg_hash = Sha256dHash::from_data(&unsigned.encode()[..]);
-               let sig = self.secp_ctx.sign(&Message::from_slice(&msg_hash[..]).unwrap(), &self.our_network_key).unwrap(); //TODO Can we unwrap here?
+               let sig = self.secp_ctx.sign(&Message::from_slice(&msg_hash[..]).unwrap(), &self.our_network_key); //TODO Can we unwrap here?
 
                Ok(msgs::ChannelUpdate {
                        signature: sig,
@@ -770,10 +952,14 @@ impl ChannelManager {
                }
 
                let mut events = self.pending_events.lock().unwrap();
-               events.push(events::Event::SendHTLCs {
+               events.push(events::Event::UpdateHTLCs {
                        node_id: first_hop_node_id,
-                       msgs: vec![update_add],
-                       commitment_msg: commitment_signed,
+                       updates: msgs::CommitmentUpdate {
+                               update_add_htlcs: vec![update_add],
+                               update_fulfill_htlcs: Vec::new(),
+                               update_fail_htlcs: Vec::new(),
+                               commitment_signed,
+                       },
                });
                Ok(())
        }
@@ -839,7 +1025,7 @@ impl ChannelManager {
 
                let (announcement, our_bitcoin_sig) = chan.get_channel_announcement(self.get_our_node_id(), self.genesis_hash.clone())?;
                let msghash = Message::from_slice(&Sha256dHash::from_data(&announcement.encode()[..])[..]).unwrap();
-               let our_node_sig = secp_call!(self.secp_ctx.sign(&msghash, &self.our_network_key));
+               let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
 
                Ok(Some(msgs::AnnouncementSignatures {
                        channel_id: chan.channel_id(),
@@ -910,10 +1096,14 @@ impl ChannelManager {
                                                                continue;
                                                        },
                                                };
-                                               new_events.push((Some(monitor), events::Event::SendHTLCs {
+                                               new_events.push((Some(monitor), events::Event::UpdateHTLCs {
                                                        node_id: forward_chan.get_their_node_id(),
-                                                       msgs: add_htlc_msgs,
-                                                       commitment_msg: commitment_msg,
+                                                       updates: msgs::CommitmentUpdate {
+                                                               update_add_htlcs: add_htlc_msgs,
+                                                               update_fulfill_htlcs: Vec::new(),
+                                                               update_fail_htlcs: Vec::new(),
+                                                               commitment_signed: commitment_msg,
+                                                       },
                                                }));
                                        }
                                } else {
@@ -1029,11 +1219,14 @@ impl ChannelManager {
                                                }
 
                                                let mut pending_events = self.pending_events.lock().unwrap();
-                                               //TODO: replace by HandleError ? UpdateFailHTLC in handle_update_add_htlc need also to build a CommitmentSigned
-                                               pending_events.push(events::Event::SendFailHTLC {
+                                               pending_events.push(events::Event::UpdateHTLCs {
                                                        node_id,
-                                                       msg: msg,
-                                                       commitment_msg: commitment_msg,
+                                                       updates: msgs::CommitmentUpdate {
+                                                               update_add_htlcs: Vec::new(),
+                                                               update_fulfill_htlcs: Vec::new(),
+                                                               update_fail_htlcs: vec![msg],
+                                                               commitment_signed: commitment_msg,
+                                                       },
                                                });
                                        },
                                        None => {},
@@ -1125,10 +1318,14 @@ impl ChannelManager {
 
                                if let Some((msg, commitment_msg)) = fulfill_msgs.0 {
                                        let mut pending_events = self.pending_events.lock().unwrap();
-                                       pending_events.push(events::Event::SendFulfillHTLC {
+                                       pending_events.push(events::Event::UpdateHTLCs {
                                                node_id: node_id,
-                                               msg,
-                                               commitment_msg,
+                                               updates: msgs::CommitmentUpdate {
+                                                       update_add_htlcs: Vec::new(),
+                                                       update_fulfill_htlcs: vec![msg],
+                                                       update_fail_htlcs: Vec::new(),
+                                                       commitment_signed: commitment_msg,
+                                               }
                                        });
                                }
                                true
@@ -1138,7 +1335,7 @@ impl ChannelManager {
 
        /// Gets the node_id held by this ChannelManager
        pub fn get_our_node_id(&self) -> PublicKey {
-               PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).unwrap()
+               PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key)
        }
 
        /// Used to restore channels to normal operation after a
@@ -1195,7 +1392,7 @@ impl ChainListener for ChannelManager {
                                if let Some(funding_txo) = channel.get_funding_txo() {
                                        for tx in txn_matched {
                                                for inp in tx.input.iter() {
-                                                       if inp.prev_hash == funding_txo.txid && inp.prev_index == funding_txo.index as u32 {
+                                                       if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
                                                                if let Some(short_id) = channel.get_short_channel_id() {
                                                                        short_to_id.remove(&short_id);
                                                                }
@@ -1507,183 +1704,34 @@ impl ChannelMessageHandler for ChannelManager {
                //encrypted with the same key. Its not immediately obvious how to usefully exploit that,
                //but we should prevent it anyway.
 
-               let shared_secret = SharedSecret::new(&self.secp_ctx, &msg.onion_routing_packet.public_key, &self.our_network_key);
-               let (rho, mu) = ChannelManager::gen_rho_mu_from_shared_secret(&shared_secret);
-
-               macro_rules! get_onion_hash {
-                       () => {
-                               {
-                                       let mut sha = Sha256::new();
-                                       sha.input(&msg.onion_routing_packet.hop_data);
-                                       let mut onion_hash = [0; 32];
-                                       sha.result(&mut onion_hash);
-                                       onion_hash
-                               }
-                       }
-               }
-
-               macro_rules! return_err {
-                       ($msg: expr, $err_code: expr, $data: expr) => {
-                               return Err(msgs::HandleError {
-                                       err: $msg,
-                                       action: Some(msgs::ErrorAction::UpdateFailHTLC {
-                                               msg: msgs::UpdateFailHTLC {
-                                                       channel_id: msg.channel_id,
-                                                       htlc_id: msg.htlc_id,
-                                                       reason: ChannelManager::build_first_hop_failure_packet(&shared_secret, $err_code, $data),
-                                               }
-                                       }),
-                               });
-                       }
-               }
-
-               if msg.onion_routing_packet.version != 0 {
-                       //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
-                       //sha256_of_onion error data packets), or the entire onion_routing_packet. Either way,
-                       //the hash doesn't really serve any purpuse - in the case of hashing all data, the
-                       //receiving node would have to brute force to figure out which version was put in the
-                       //packet by the node that send us the message, in the case of hashing the hop_data, the
-                       //node knows the HMAC matched, so they already know what is there...
-                       return_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4, &get_onion_hash!());
-               }
-
-               let mut hmac = Hmac::new(Sha256::new(), &mu);
-               hmac.input(&msg.onion_routing_packet.hop_data);
-               hmac.input(&msg.payment_hash);
-               if hmac.result() != MacResult::new(&msg.onion_routing_packet.hmac) {
-                       return_err!("HMAC Check failed", 0x8000 | 0x4000 | 5, &get_onion_hash!());
-               }
-
-               let mut chacha = ChaCha20::new(&rho, &[0u8; 8]);
-               let next_hop_data = {
-                       let mut decoded = [0; 65];
-                       chacha.process(&msg.onion_routing_packet.hop_data[0..65], &mut decoded);
-                       match msgs::OnionHopData::decode(&decoded[..]) {
-                               Err(err) => {
-                                       let error_code = match err {
-                                               msgs::DecodeError::UnknownRealmByte => 0x4000 | 1,
-                                               _ => 0x2000 | 2, // Should never happen
-                                       };
-                                       return_err!("Unable to decode our hop data", error_code, &[0;0]);
-                               },
-                               Ok(msg) => msg
-                       }
-               };
-
-               //TODO: Check that msg.cltv_expiry is within acceptable bounds!
-
-               let mut pending_forward_info = if next_hop_data.hmac == [0; 32] {
-                               // OUR PAYMENT!
-                               if next_hop_data.data.amt_to_forward != msg.amount_msat {
-                                       return_err!("Upstream node sent less than we were supposed to receive in payment", 19, &byte_utils::be64_to_array(msg.amount_msat));
-                               }
-                               if next_hop_data.data.outgoing_cltv_value != msg.cltv_expiry {
-                                       return_err!("Upstream node set CLTV to the wrong value", 18, &byte_utils::be32_to_array(msg.cltv_expiry));
-                               }
-
-                               // Note that we could obviously respond immediately with an update_fulfill_htlc
-                               // message, however that would leak that we are the recipient of this payment, so
-                               // instead we stay symmetric with the forwarding case, only responding (after a
-                               // delay) once they've send us a commitment_signed!
-
-                               PendingForwardHTLCInfo {
-                                       onion_packet: None,
-                                       payment_hash: msg.payment_hash.clone(),
-                                       short_channel_id: 0,
-                                       prev_short_channel_id: 0,
-                                       amt_to_forward: next_hop_data.data.amt_to_forward,
-                                       outgoing_cltv_value: next_hop_data.data.outgoing_cltv_value,
-                               }
-                       } else {
-                               let mut new_packet_data = [0; 20*65];
-                               chacha.process(&msg.onion_routing_packet.hop_data[65..], &mut new_packet_data[0..19*65]);
-                               chacha.process(&ChannelManager::ZERO[0..65], &mut new_packet_data[19*65..]);
-
-                               let mut new_pubkey = msg.onion_routing_packet.public_key.clone();
-
-                               let blinding_factor = {
-                                       let mut sha = Sha256::new();
-                                       sha.input(&new_pubkey.serialize()[..]);
-                                       sha.input(&shared_secret[..]);
-                                       let mut res = [0u8; 32];
-                                       sha.result(&mut res);
-                                       match SecretKey::from_slice(&self.secp_ctx, &res) {
-                                               Err(_) => {
-                                                       // Return temporary node failure as its technically our issue, not the
-                                                       // channel's issue.
-                                                       return_err!("Blinding factor is an invalid private key", 0x2000 | 2, &[0;0]);
-                                               },
-                                               Ok(key) => key
-                                       }
-                               };
-
-                               match new_pubkey.mul_assign(&self.secp_ctx, &blinding_factor) {
-                                       Err(_) => {
-                                               // Return temporary node failure as its technically our issue, not the
-                                               // channel's issue.
-                                               return_err!("New blinding factor is an invalid private key", 0x2000 | 2, &[0;0]);
-                                       },
-                                       Ok(_) => {}
-                               };
-
-                               let outgoing_packet = msgs::OnionPacket {
-                                       version: 0,
-                                       public_key: new_pubkey,
-                                       hop_data: new_packet_data,
-                                       hmac: next_hop_data.hmac.clone(),
-                               };
-
-                               PendingForwardHTLCInfo {
-                                       onion_packet: Some(outgoing_packet),
-                                       payment_hash: msg.payment_hash.clone(),
-                                       short_channel_id: next_hop_data.data.short_channel_id,
-                                       prev_short_channel_id: 0,
-                                       amt_to_forward: next_hop_data.data.amt_to_forward,
-                                       outgoing_cltv_value: next_hop_data.data.outgoing_cltv_value,
-                               }
-                       };
-
-               let mut channel_state_lock = self.channel_state.lock().unwrap();
+               let (mut pending_forward_info, shared_secret, mut channel_state_lock) = self.decode_update_add_htlc_onion(msg);
                let channel_state = channel_state_lock.borrow_parts();
 
-               if pending_forward_info.onion_packet.is_some() { // If short_channel_id is 0 here, we'll reject them in the body here
-                       let forwarding_id = match channel_state.short_to_id.get(&pending_forward_info.short_channel_id) {
-                               None => {
-                                       return_err!("Don't have available channel for forwarding as requested.", 0x4000 | 10, &[0;0]);
-                               },
-                               Some(id) => id.clone(),
-                       };
-                       let chan = channel_state.by_id.get_mut(&forwarding_id).unwrap();
-                       let fee = chan.get_our_fee_base_msat(&*self.fee_estimator) + (pending_forward_info.amt_to_forward * self.fee_proportional_millionths as u64 / 1000000) as u32;
-                       if msg.amount_msat < fee as u64 || (msg.amount_msat - fee as u64) < pending_forward_info.amt_to_forward {
-                               log_debug!(self, "HTLC {} incorrect amount: in {} out {} fee required {}", msg.htlc_id, msg.amount_msat, pending_forward_info.amt_to_forward, fee);
-                               //TODO: send back "channel_update" with new fee parameters in onion failure packet
-                               return_err!("Prior hop has deviated from specified fees parameters or origin node has obsolete ones", 0x1000 | 12, &[0;0]);
-                       }
-                       if (msg.cltv_expiry as u64) < pending_forward_info.outgoing_cltv_value as u64 + CLTV_EXPIRY_DELTA as u64 {
-                               log_debug!(self, "HTLC {} incorrect CLTV: in {} out {} delta required {}", msg.htlc_id, msg.cltv_expiry, pending_forward_info.outgoing_cltv_value, CLTV_EXPIRY_DELTA);
-                               return_err!("Forwarding node has tampered with the intended HTLC values or origin node has an obsolete cltv_expiry_delta", 0x1000 | 13, &[0;0]);
-                       }
-
-                       if !chan.is_live() {
-                               let chan_update = self.get_channel_update(chan).unwrap();
-                               return_err!("Forwarding channel is not in a ready state.", 0x1000 | 7, &chan_update.encode_with_len()[..]);
-                       }
-               }
-
                let claimable_htlcs_entry = channel_state.claimable_htlcs.entry(msg.payment_hash.clone());
 
                // We dont correctly handle payments that route through us twice on their way to their
                // destination. That's OK since those nodes are probably busted or trying to do network
                // mapping through repeated loops. In either case, we want them to stop talking to us, so
                // we send permanent_node_failure.
-               if let &hash_map::Entry::Occupied(ref e) = &claimable_htlcs_entry {
-                       let mut acceptable_cycle = false;
-                       if let &PendingOutboundHTLC::OutboundRoute { .. } = e.get() {
-                               acceptable_cycle = pending_forward_info.short_channel_id == 0;
-                       }
-                       if !acceptable_cycle {
-                               return_err!("Payment looped through us twice", 0x4000 | 0x2000 | 2, &[0;0]);
+               let mut will_forward = false;
+               if let PendingHTLCStatus::Forward(PendingForwardHTLCInfo { short_channel_id, .. }) = pending_forward_info {
+                       if let &hash_map::Entry::Occupied(ref e) = &claimable_htlcs_entry {
+                               let mut acceptable_cycle = false;
+                               if let &PendingOutboundHTLC::OutboundRoute { .. } = e.get() {
+                                       acceptable_cycle = short_channel_id == 0;
+                               }
+                               if !acceptable_cycle {
+                                       log_info!(self, "Failed to accept incoming HTLC: Payment looped through us twice");
+                                       pending_forward_info = PendingHTLCStatus::Fail(msgs::UpdateFailHTLC {
+                                               channel_id: msg.channel_id,
+                                               htlc_id: msg.htlc_id,
+                                               reason: ChannelManager::build_first_hop_failure_packet(&shared_secret, 0x4000 | 0x2000 | 2, &[0;0]),
+                                       });
+                               } else {
+                                       will_forward = true;
+                               }
+                       } else {
+                               will_forward = true;
                        }
                }
 
@@ -1696,33 +1744,37 @@ impl ChannelMessageHandler for ChannelManager {
                                        return Err(HandleError{err: "Channel not yet available for receiving HTLCs", action: None});
                                }
                                let short_channel_id = chan.get_short_channel_id().unwrap();
-                               pending_forward_info.prev_short_channel_id = short_channel_id;
+                               if let PendingHTLCStatus::Forward(ref mut forward_info) = pending_forward_info {
+                                       forward_info.prev_short_channel_id = short_channel_id;
+                               }
                                (short_channel_id, chan.update_add_htlc(&msg, pending_forward_info)?)
                        },
                        None => return Err(HandleError{err: "Failed to find corresponding channel", action: None}),
                };
 
-               match claimable_htlcs_entry {
-                       hash_map::Entry::Occupied(mut e) => {
-                               let outbound_route = e.get_mut();
-                               let (route, session_priv) = match outbound_route {
-                                       &mut PendingOutboundHTLC::OutboundRoute { ref route, ref session_priv } => {
-                                               (route.clone(), session_priv.clone())
-                                       },
-                                       _ => unreachable!(),
-                               };
-                               *outbound_route = PendingOutboundHTLC::CycledRoute {
-                                       source_short_channel_id,
-                                       incoming_packet_shared_secret: shared_secret,
-                                       route,
-                                       session_priv,
-                               };
-                       },
-                       hash_map::Entry::Vacant(e) => {
-                               e.insert(PendingOutboundHTLC::IntermediaryHopData {
-                                       source_short_channel_id,
-                                       incoming_packet_shared_secret: shared_secret,
-                               });
+               if will_forward {
+                       match claimable_htlcs_entry {
+                               hash_map::Entry::Occupied(mut e) => {
+                                       let outbound_route = e.get_mut();
+                                       let (route, session_priv) = match outbound_route {
+                                               &mut PendingOutboundHTLC::OutboundRoute { ref route, ref session_priv } => {
+                                                       (route.clone(), session_priv.clone())
+                                               },
+                                               _ => unreachable!(),
+                                       };
+                                       *outbound_route = PendingOutboundHTLC::CycledRoute {
+                                               source_short_channel_id,
+                                               incoming_packet_shared_secret: shared_secret,
+                                               route,
+                                               session_priv,
+                                       };
+                               },
+                               hash_map::Entry::Vacant(e) => {
+                                       e.insert(PendingOutboundHTLC::IntermediaryHopData {
+                                               source_short_channel_id,
+                                               incoming_packet_shared_secret: shared_secret,
+                                       });
+                               }
                        }
                }
 
@@ -1939,7 +1991,7 @@ impl ChannelMessageHandler for ChannelManager {
                                        secp_call!(self.secp_ctx.verify(&msghash, &msg.node_signature, if were_node_one { &announcement.node_id_2 } else { &announcement.node_id_1 }));
                                        secp_call!(self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, if were_node_one { &announcement.bitcoin_key_2 } else { &announcement.bitcoin_key_1 }));
 
-                                       let our_node_sig = secp_call!(self.secp_ctx.sign(&msghash, &self.our_network_key));
+                                       let our_node_sig = self.secp_ctx.sign(&msghash, &self.our_network_key);
 
                                        (msgs::ChannelAnnouncement {
                                                node_signature_1: if were_node_one { our_node_sig } else { msg.node_signature },
@@ -2424,8 +2476,10 @@ mod tests {
        impl SendEvent {
                fn from_event(event: Event) -> SendEvent {
                        match event {
-                               Event::SendHTLCs { node_id, msgs, commitment_msg } => {
-                                       SendEvent { node_id: node_id, msgs: msgs, commitment_msg: commitment_msg }
+                               Event::UpdateHTLCs { node_id, updates: msgs::CommitmentUpdate { update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, commitment_signed } } => {
+                                       assert!(update_fulfill_htlcs.is_empty());
+                                       assert!(update_fail_htlcs.is_empty());
+                                       SendEvent { node_id: node_id, msgs: update_add_htlcs, commitment_msg: commitment_signed }
                                },
                                _ => panic!("Unexpected event type!"),
                        }
@@ -2581,9 +2635,12 @@ mod tests {
                        let events = node.node.get_and_clear_pending_events();
                        assert_eq!(events.len(), 1);
                        match events[0] {
-                               Event::SendFulfillHTLC { ref node_id, ref msg, ref commitment_msg } => {
+                               Event::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref commitment_signed } } => {
+                                       assert!(update_add_htlcs.is_empty());
+                                       assert_eq!(update_fulfill_htlcs.len(), 1);
+                                       assert!(update_fail_htlcs.is_empty());
                                        expected_next_node = node_id.clone();
-                                       next_msgs = Some((msg.clone(), commitment_msg.clone()));
+                                       next_msgs = Some((update_fulfill_htlcs[0].clone(), commitment_signed.clone()));
                                },
                                _ => panic!("Unexpected event"),
                        };
@@ -2702,9 +2759,12 @@ mod tests {
                        let events = node.node.get_and_clear_pending_events();
                        assert_eq!(events.len(), 1);
                        match events[0] {
-                               Event::SendFailHTLC { ref node_id, ref msg, ref commitment_msg } => {
+                               Event::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref commitment_signed } } => {
+                                       assert!(update_add_htlcs.is_empty());
+                                       assert!(update_fulfill_htlcs.is_empty());
+                                       assert_eq!(update_fail_htlcs.len(), 1);
                                        expected_next_node = node_id.clone();
-                                       next_msgs = Some((msg.clone(), commitment_msg.clone()));
+                                       next_msgs = Some((update_fail_htlcs[0].clone(), commitment_signed.clone()));
                                },
                                _ => panic!("Unexpected event"),
                        };
@@ -2742,7 +2802,7 @@ mod tests {
                                SecretKey::from_slice(&secp_ctx, &key_slice).unwrap()
                        };
                        let node = ChannelManager::new(node_id.clone(), 0, true, Network::Testnet, feeest.clone(), chan_monitor.clone(), chain_monitor.clone(), tx_broadcaster.clone(), Arc::clone(&logger)).unwrap();
-                       let router = Router::new(PublicKey::from_secret_key(&secp_ctx, &node_id).unwrap(), Arc::clone(&logger));
+                       let router = Router::new(PublicKey::from_secret_key(&secp_ctx, &node_id), Arc::clone(&logger));
                        nodes.push(Node { feeest, chain_monitor, tx_broadcaster, chan_monitor, node_id, node, router });
                }
 
@@ -2879,7 +2939,7 @@ mod tests {
                        res.push(explicit_tx.clone());
                } else {
                        for tx in node_txn.iter() {
-                               if tx.input.len() == 1 && tx.input[0].prev_hash == chan.3.txid() {
+                               if tx.input.len() == 1 && tx.input[0].previous_output.txid == chan.3.txid() {
                                        let mut funding_tx_map = HashMap::new();
                                        funding_tx_map.insert(chan.3.txid(), chan.3.clone());
                                        tx.verify(&funding_tx_map).unwrap();
@@ -2891,7 +2951,7 @@ mod tests {
 
                if has_htlc_tx != HTLCType::NONE {
                        for tx in node_txn.iter() {
-                               if tx.input.len() == 1 && tx.input[0].prev_hash == res[0].txid() {
+                               if tx.input.len() == 1 && tx.input[0].previous_output.txid == res[0].txid() {
                                        let mut funding_tx_map = HashMap::new();
                                        funding_tx_map.insert(res[0].txid(), res[0].clone());
                                        tx.verify(&funding_tx_map).unwrap();
@@ -2918,7 +2978,7 @@ mod tests {
                let mut found_prev = false;
 
                for tx in prev_txn {
-                       if node_txn[0].input[0].prev_hash == tx.txid() {
+                       if node_txn[0].input[0].previous_output.txid == tx.txid() {
                                let mut funding_tx_map = HashMap::new();
                                funding_tx_map.insert(tx.txid(), tx.clone());
                                node_txn[0].verify(&funding_tx_map).unwrap();
@@ -3020,7 +3080,9 @@ mod tests {
                                        let events = $node.node.get_and_clear_pending_events();
                                        assert_eq!(events.len(), 1);
                                        match events[0] {
-                                               Event::SendFulfillHTLC { ref node_id, .. } => {
+                                               Event::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fail_htlcs, .. } } => {
+                                                       assert!(update_add_htlcs.is_empty());
+                                                       assert!(update_fail_htlcs.is_empty());
                                                        assert_eq!(*node_id, $prev_node.node.get_our_node_id());
                                                },
                                                _ => panic!("Unexpected event"),