Log peer features in peer_handler (and check for all req bits)
[rust-lightning] / src / ln / msgs.rs
index fc942ab5a2022dbe30eb303c3d4279362c81d881..92e900a212058fde85d73243951de417e7af2ae9 100644 (file)
@@ -2,29 +2,16 @@ use secp256k1::key::PublicKey;
 use secp256k1::{Secp256k1, Signature};
 use secp256k1;
 use bitcoin::util::hash::Sha256dHash;
-use bitcoin::network::serialize::{deserialize,serialize};
 use bitcoin::blockdata::script::Script;
 
 use std::error::Error;
 use std::{cmp, fmt};
+use std::io::Read;
 use std::result::Result;
 
 use util::{byte_utils, internal_traits, events};
-use util::ser::{Readable, Reader, Writeable, Writer};
-
-pub trait MsgEncodable {
-       fn encode(&self) -> Vec<u8>;
-       #[inline]
-       fn encoded_len(&self) -> usize { self.encode().len() }
-       #[inline]
-       fn encode_with_len(&self) -> Vec<u8> {
-               let enc = self.encode();
-               let mut res = Vec::with_capacity(enc.len() + 2);
-               res.extend_from_slice(&byte_utils::be16_to_array(enc.len() as u16));
-               res.extend_from_slice(&enc);
-               res
-       }
-}
+use util::ser::{Readable, Writeable, Writer};
+
 #[derive(Debug)]
 pub enum DecodeError {
        /// Unknown realm byte in an OnionHopData packet
@@ -49,9 +36,6 @@ pub enum DecodeError {
        /// 1 or 0 is not found for boolean value
        InvalidValue,
 }
-pub trait MsgDecodable: Sized {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError>;
-}
 
 /// Tracks localfeatures which are only in init messages
 #[derive(Clone, PartialEq)]
@@ -456,13 +440,17 @@ pub trait ChannelMessageHandler : events::EventsProvider + Send + Sync {
        // Channel-to-announce:
        fn handle_announcement_signatures(&self, their_node_id: &PublicKey, msg: &AnnouncementSignatures) -> Result<(), HandleError>;
 
-       // Error conditions:
+       // Connection loss/reestablish:
        /// Indicates a connection to the peer failed/an existing connection was lost. If no connection
        /// is believed to be possible in the future (eg they're sending us messages we don't
        /// understand or indicate they require unknown feature bits), no_connection_possible is set
        /// and any outstanding channels should be failed.
        fn peer_disconnected(&self, their_node_id: &PublicKey, no_connection_possible: bool);
 
+       fn peer_connected(&self, their_node_id: &PublicKey) -> Vec<ChannelReestablish>;
+       fn handle_channel_reestablish(&self, their_node_id: &PublicKey, msg: &ChannelReestablish) -> Result<(Option<FundingLocked>, Option<RevokeAndACK>, Option<CommitmentUpdate>), HandleError>;
+
+       // Error:
        fn handle_error(&self, their_node_id: &PublicKey, msg: &ErrorMessage);
 }
 
@@ -551,1155 +539,10 @@ impl From<::std::io::Error> for DecodeError {
        }
 }
 
-macro_rules! secp_pubkey {
-       ( $ctx: expr, $slice: expr ) => {
-               match PublicKey::from_slice($ctx, $slice) {
-                       Ok(key) => key,
-                       Err(_) => return Err(DecodeError::BadPublicKey)
-               }
-       };
-}
-
-macro_rules! secp_signature {
-       ( $ctx: expr, $slice: expr ) => {
-               match Signature::from_compact($ctx, $slice) {
-                       Ok(sig) => sig,
-                       Err(_) => return Err(DecodeError::BadSignature)
-               }
-       };
-}
-
-impl MsgDecodable for LocalFeatures {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 2 { return Err(DecodeError::ShortRead); }
-               let len = byte_utils::slice_to_be16(&v[0..2]) as usize;
-               if v.len() < len + 2 { return Err(DecodeError::ShortRead); }
-               let mut flags = Vec::with_capacity(len);
-               flags.extend_from_slice(&v[2..2 + len]);
-               Ok(Self {
-                       flags: flags
-               })
-       }
-}
-impl MsgEncodable for LocalFeatures {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(self.flags.len() + 2);
-               res.extend_from_slice(&byte_utils::be16_to_array(self.flags.len() as u16));
-               res.extend_from_slice(&self.flags[..]);
-               res
-       }
-       fn encoded_len(&self) -> usize { self.flags.len() + 2 }
-}
-
-impl MsgDecodable for GlobalFeatures {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 2 { return Err(DecodeError::ShortRead); }
-               let len = byte_utils::slice_to_be16(&v[0..2]) as usize;
-               if v.len() < len + 2 { return Err(DecodeError::ShortRead); }
-               let mut flags = Vec::with_capacity(len);
-               flags.extend_from_slice(&v[2..2 + len]);
-               Ok(Self {
-                       flags: flags
-               })
-       }
-}
-impl MsgEncodable for GlobalFeatures {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(self.flags.len() + 2);
-               res.extend_from_slice(&byte_utils::be16_to_array(self.flags.len() as u16));
-               res.extend_from_slice(&self.flags[..]);
-               res
-       }
-       fn encoded_len(&self) -> usize { self.flags.len() + 2 }
-}
-
-impl MsgDecodable for Init {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               let global_features = GlobalFeatures::decode(v)?;
-               if v.len() < global_features.flags.len() + 4 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let local_features = LocalFeatures::decode(&v[global_features.flags.len() + 2..])?;
-               Ok(Self {
-                       global_features: global_features,
-                       local_features: local_features,
-               })
-       }
-}
-impl MsgEncodable for Init {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(self.global_features.flags.len() + self.local_features.flags.len());
-               res.extend_from_slice(&self.global_features.encode()[..]);
-               res.extend_from_slice(&self.local_features.encode()[..]);
-               res
-       }
-}
-
-impl MsgDecodable for Ping {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 4 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let ponglen = byte_utils::slice_to_be16(&v[0..2]);
-               let byteslen = byte_utils::slice_to_be16(&v[2..4]);
-               if v.len() < 4 + byteslen as usize {
-                       return Err(DecodeError::ShortRead);
-               }
-               Ok(Self {
-                       ponglen,
-                       byteslen,
-               })
-       }
-}
-impl MsgEncodable for Ping {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(self.byteslen as usize + 2);
-               res.extend_from_slice(&byte_utils::be16_to_array(self.byteslen));
-               res.resize(2 + self.byteslen as usize, 0);
-               res
-       }
-}
-
-impl MsgDecodable for Pong {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 2 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let byteslen = byte_utils::slice_to_be16(&v[0..2]);
-               if v.len() < 2 + byteslen as usize {
-                       return Err(DecodeError::ShortRead);
-               }
-               Ok(Self {
-                       byteslen
-               })
-       }
-}
-impl MsgEncodable for Pong {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(self.byteslen as usize + 2);
-               res.extend_from_slice(&byte_utils::be16_to_array(self.byteslen));
-               res.resize(2 + self.byteslen as usize, 0);
-               res
-       }
-}
-
-impl MsgDecodable for OpenChannel {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 2*32+6*8+4+2*2+6*33+1 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let ctx = Secp256k1::without_caps();
-
-               let mut shutdown_scriptpubkey = None;
-               if v.len() >= 321 {
-                       let len = byte_utils::slice_to_be16(&v[319..321]) as usize;
-                       if v.len() < 321+len {
-                               return Err(DecodeError::ShortRead);
-                       }
-                       shutdown_scriptpubkey = Some(Script::from(v[321..321+len].to_vec()));
-               }
-               let mut temp_channel_id = [0; 32];
-               temp_channel_id[..].copy_from_slice(&v[32..64]);
-               Ok(OpenChannel {
-                       chain_hash: deserialize(&v[0..32]).unwrap(),
-                       temporary_channel_id: temp_channel_id,
-                       funding_satoshis: byte_utils::slice_to_be64(&v[64..72]),
-                       push_msat: byte_utils::slice_to_be64(&v[72..80]),
-                       dust_limit_satoshis: byte_utils::slice_to_be64(&v[80..88]),
-                       max_htlc_value_in_flight_msat: byte_utils::slice_to_be64(&v[88..96]),
-                       channel_reserve_satoshis: byte_utils::slice_to_be64(&v[96..104]),
-                       htlc_minimum_msat: byte_utils::slice_to_be64(&v[104..112]),
-                       feerate_per_kw: byte_utils::slice_to_be32(&v[112..116]),
-                       to_self_delay: byte_utils::slice_to_be16(&v[116..118]),
-                       max_accepted_htlcs: byte_utils::slice_to_be16(&v[118..120]),
-                       funding_pubkey: secp_pubkey!(&ctx, &v[120..153]),
-                       revocation_basepoint: secp_pubkey!(&ctx, &v[153..186]),
-                       payment_basepoint: secp_pubkey!(&ctx, &v[186..219]),
-                       delayed_payment_basepoint: secp_pubkey!(&ctx, &v[219..252]),
-                       htlc_basepoint: secp_pubkey!(&ctx, &v[252..285]),
-                       first_per_commitment_point: secp_pubkey!(&ctx, &v[285..318]),
-                       channel_flags: v[318],
-                       shutdown_scriptpubkey: shutdown_scriptpubkey
-               })
-       }
-}
-impl MsgEncodable for OpenChannel {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = match &self.shutdown_scriptpubkey {
-                       &Some(ref script) => Vec::with_capacity(319 + 2 + script.len()),
-                       &None => Vec::with_capacity(319),
-               };
-               res.extend_from_slice(&serialize(&self.chain_hash).unwrap());
-               res.extend_from_slice(&serialize(&self.temporary_channel_id).unwrap());
-               res.extend_from_slice(&byte_utils::be64_to_array(self.funding_satoshis));
-               res.extend_from_slice(&byte_utils::be64_to_array(self.push_msat));
-               res.extend_from_slice(&byte_utils::be64_to_array(self.dust_limit_satoshis));
-               res.extend_from_slice(&byte_utils::be64_to_array(self.max_htlc_value_in_flight_msat));
-               res.extend_from_slice(&byte_utils::be64_to_array(self.channel_reserve_satoshis));
-               res.extend_from_slice(&byte_utils::be64_to_array(self.htlc_minimum_msat));
-               res.extend_from_slice(&byte_utils::be32_to_array(self.feerate_per_kw));
-               res.extend_from_slice(&byte_utils::be16_to_array(self.to_self_delay));
-               res.extend_from_slice(&byte_utils::be16_to_array(self.max_accepted_htlcs));
-               res.extend_from_slice(&self.funding_pubkey.serialize());
-               res.extend_from_slice(&self.revocation_basepoint.serialize());
-               res.extend_from_slice(&self.payment_basepoint.serialize());
-               res.extend_from_slice(&self.delayed_payment_basepoint.serialize());
-               res.extend_from_slice(&self.htlc_basepoint.serialize());
-               res.extend_from_slice(&self.first_per_commitment_point.serialize());
-               res.push(self.channel_flags);
-               if let &Some(ref script) = &self.shutdown_scriptpubkey {
-                       res.extend_from_slice(&byte_utils::be16_to_array(script.len() as u16));
-                       res.extend_from_slice(&script[..]);
-               }
-               res
-       }
-}
-
-impl MsgDecodable for AcceptChannel {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+4*8+4+2*2+6*33 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let ctx = Secp256k1::without_caps();
-
-               let mut shutdown_scriptpubkey = None;
-               if v.len() >= 272 {
-                       let len = byte_utils::slice_to_be16(&v[270..272]) as usize;
-                       if v.len() < 272+len {
-                               return Err(DecodeError::ShortRead);
-                       }
-                       shutdown_scriptpubkey = Some(Script::from(v[272..272+len].to_vec()));
-               }
-
-               let mut temporary_channel_id = [0; 32];
-               temporary_channel_id[..].copy_from_slice(&v[0..32]);
-               Ok(Self {
-                       temporary_channel_id,
-                       dust_limit_satoshis: byte_utils::slice_to_be64(&v[32..40]),
-                       max_htlc_value_in_flight_msat: byte_utils::slice_to_be64(&v[40..48]),
-                       channel_reserve_satoshis: byte_utils::slice_to_be64(&v[48..56]),
-                       htlc_minimum_msat: byte_utils::slice_to_be64(&v[56..64]),
-                       minimum_depth: byte_utils::slice_to_be32(&v[64..68]),
-                       to_self_delay: byte_utils::slice_to_be16(&v[68..70]),
-                       max_accepted_htlcs: byte_utils::slice_to_be16(&v[70..72]),
-                       funding_pubkey: secp_pubkey!(&ctx, &v[72..105]),
-                       revocation_basepoint: secp_pubkey!(&ctx, &v[105..138]),
-                       payment_basepoint: secp_pubkey!(&ctx, &v[138..171]),
-                       delayed_payment_basepoint: secp_pubkey!(&ctx, &v[171..204]),
-                       htlc_basepoint: secp_pubkey!(&ctx, &v[204..237]),
-                       first_per_commitment_point: secp_pubkey!(&ctx, &v[237..270]),
-                       shutdown_scriptpubkey: shutdown_scriptpubkey
-               })
-       }
-}
-impl MsgEncodable for AcceptChannel {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = match &self.shutdown_scriptpubkey {
-                       &Some(ref script) => Vec::with_capacity(270 + 2 + script.len()),
-                       &None => Vec::with_capacity(270),
-               };
-               res.extend_from_slice(&self.temporary_channel_id);
-               res.extend_from_slice(&byte_utils::be64_to_array(self.dust_limit_satoshis));
-               res.extend_from_slice(&byte_utils::be64_to_array(self.max_htlc_value_in_flight_msat));
-               res.extend_from_slice(&byte_utils::be64_to_array(self.channel_reserve_satoshis));
-               res.extend_from_slice(&byte_utils::be64_to_array(self.htlc_minimum_msat));
-               res.extend_from_slice(&byte_utils::be32_to_array(self.minimum_depth));
-               res.extend_from_slice(&byte_utils::be16_to_array(self.to_self_delay));
-               res.extend_from_slice(&byte_utils::be16_to_array(self.max_accepted_htlcs));
-               res.extend_from_slice(&self.funding_pubkey.serialize());
-               res.extend_from_slice(&self.revocation_basepoint.serialize());
-               res.extend_from_slice(&self.payment_basepoint.serialize());
-               res.extend_from_slice(&self.delayed_payment_basepoint.serialize());
-               res.extend_from_slice(&self.htlc_basepoint.serialize());
-               res.extend_from_slice(&self.first_per_commitment_point.serialize());
-               if let &Some(ref script) = &self.shutdown_scriptpubkey {
-                       res.extend_from_slice(&byte_utils::be16_to_array(script.len() as u16));
-                       res.extend_from_slice(&script[..]);
-               }
-               res
-       }
-}
-
-impl MsgDecodable for FundingCreated {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+32+2+64 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let ctx = Secp256k1::without_caps();
-               let mut temporary_channel_id = [0; 32];
-               temporary_channel_id[..].copy_from_slice(&v[0..32]);
-               Ok(Self {
-                       temporary_channel_id,
-                       funding_txid: deserialize(&v[32..64]).unwrap(),
-                       funding_output_index: byte_utils::slice_to_be16(&v[64..66]),
-                       signature: secp_signature!(&ctx, &v[66..130]),
-               })
-       }
-}
-impl MsgEncodable for FundingCreated {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32+32+2+64);
-               res.extend_from_slice(&self.temporary_channel_id);
-               res.extend_from_slice(&serialize(&self.funding_txid).unwrap()[..]);
-               res.extend_from_slice(&byte_utils::be16_to_array(self.funding_output_index));
-               let secp_ctx = Secp256k1::without_caps();
-               res.extend_from_slice(&self.signature.serialize_compact(&secp_ctx));
-               res
-       }
-}
-
-impl MsgDecodable for FundingSigned {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+64 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let ctx = Secp256k1::without_caps();
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-               Ok(Self {
-                       channel_id,
-                       signature: secp_signature!(&ctx, &v[32..96]),
-               })
-       }
-}
-impl MsgEncodable for FundingSigned {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32+64);
-               res.extend_from_slice(&self.channel_id);
-               res.extend_from_slice(&self.signature.serialize_compact(&Secp256k1::without_caps()));
-               res
-       }
-}
-
-impl MsgDecodable for FundingLocked {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+33 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let ctx = Secp256k1::without_caps();
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-               Ok(Self {
-                       channel_id,
-                       next_per_commitment_point: secp_pubkey!(&ctx, &v[32..65]),
-               })
-       }
-}
-impl MsgEncodable for FundingLocked {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32+33);
-               res.extend_from_slice(&self.channel_id);
-               res.extend_from_slice(&self.next_per_commitment_point.serialize());
-               res
-       }
-}
-
-impl MsgDecodable for Shutdown {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32 + 2 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let scriptlen = byte_utils::slice_to_be16(&v[32..34]) as usize;
-               if v.len() < 32 + 2 + scriptlen {
-                       return Err(DecodeError::ShortRead);
-               }
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-               Ok(Self {
-                       channel_id,
-                       scriptpubkey: Script::from(v[34..34 + scriptlen].to_vec()),
-               })
-       }
-}
-impl MsgEncodable for Shutdown {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32 + 2 + self.scriptpubkey.len());
-               res.extend_from_slice(&self.channel_id);
-               res.extend_from_slice(&byte_utils::be16_to_array(self.scriptpubkey.len() as u16));
-               res.extend_from_slice(&self.scriptpubkey[..]);
-               res
-       }
-}
-
-impl MsgDecodable for ClosingSigned {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32 + 8 + 64 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let secp_ctx = Secp256k1::without_caps();
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-               Ok(Self {
-                       channel_id,
-                       fee_satoshis: byte_utils::slice_to_be64(&v[32..40]),
-                       signature: secp_signature!(&secp_ctx, &v[40..104]),
-               })
-       }
-}
-impl MsgEncodable for ClosingSigned {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32+8+64);
-               res.extend_from_slice(&self.channel_id);
-               res.extend_from_slice(&byte_utils::be64_to_array(self.fee_satoshis));
-               let secp_ctx = Secp256k1::without_caps();
-               res.extend_from_slice(&self.signature.serialize_compact(&secp_ctx));
-               res
-       }
-}
-
-impl MsgDecodable for UpdateAddHTLC {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+8+8+32+4+1+33+20*65+32 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-               let mut payment_hash = [0; 32];
-               payment_hash.copy_from_slice(&v[48..80]);
-               Ok(Self{
-                       channel_id,
-                       htlc_id: byte_utils::slice_to_be64(&v[32..40]),
-                       amount_msat: byte_utils::slice_to_be64(&v[40..48]),
-                       payment_hash,
-                       cltv_expiry: byte_utils::slice_to_be32(&v[80..84]),
-                       onion_routing_packet: OnionPacket::decode(&v[84..84+1366])?,
-               })
-       }
-}
-impl MsgEncodable for UpdateAddHTLC {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32+8+8+32+4+1366);
-               res.extend_from_slice(&self.channel_id);
-               res.extend_from_slice(&byte_utils::be64_to_array(self.htlc_id));
-               res.extend_from_slice(&byte_utils::be64_to_array(self.amount_msat));
-               res.extend_from_slice(&self.payment_hash);
-               res.extend_from_slice(&byte_utils::be32_to_array(self.cltv_expiry));
-               res.extend_from_slice(&self.onion_routing_packet.encode()[..]);
-               res
-       }
-}
-
-impl MsgDecodable for UpdateFulfillHTLC {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+8+32 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-               let mut payment_preimage = [0; 32];
-               payment_preimage.copy_from_slice(&v[40..72]);
-               Ok(Self{
-                       channel_id,
-                       htlc_id: byte_utils::slice_to_be64(&v[32..40]),
-                       payment_preimage,
-               })
-       }
-}
-impl MsgEncodable for UpdateFulfillHTLC {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32+8+32);
-               res.extend_from_slice(&self.channel_id);
-               res.extend_from_slice(&byte_utils::be64_to_array(self.htlc_id));
-               res.extend_from_slice(&self.payment_preimage);
-               res
-       }
-}
-
-impl MsgDecodable for UpdateFailHTLC {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+8 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-               Ok(Self{
-                       channel_id,
-                       htlc_id: byte_utils::slice_to_be64(&v[32..40]),
-                       reason: OnionErrorPacket::decode(&v[40..])?,
-               })
-       }
-}
-impl MsgEncodable for UpdateFailHTLC {
-       fn encode(&self) -> Vec<u8> {
-               let reason = self.reason.encode();
-               let mut res = Vec::with_capacity(32+8+reason.len());
-               res.extend_from_slice(&self.channel_id);
-               res.extend_from_slice(&byte_utils::be64_to_array(self.htlc_id));
-               res.extend_from_slice(&reason[..]);
-               res
-       }
-}
-
-impl MsgDecodable for UpdateFailMalformedHTLC {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+8+32+2 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-               let mut sha256_of_onion = [0; 32];
-               sha256_of_onion.copy_from_slice(&v[40..72]);
-               Ok(Self{
-                       channel_id,
-                       htlc_id: byte_utils::slice_to_be64(&v[32..40]),
-                       sha256_of_onion,
-                       failure_code: byte_utils::slice_to_be16(&v[72..74]),
-               })
-       }
-}
-impl MsgEncodable for UpdateFailMalformedHTLC {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32+8+32+2);
-               res.extend_from_slice(&self.channel_id);
-               res.extend_from_slice(&byte_utils::be64_to_array(self.htlc_id));
-               res.extend_from_slice(&self.sha256_of_onion);
-               res.extend_from_slice(&byte_utils::be16_to_array(self.failure_code));
-               res
-       }
-}
-
-impl MsgDecodable for CommitmentSigned {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+64+2 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-
-               let htlcs = byte_utils::slice_to_be16(&v[96..98]) as usize;
-               if v.len() < 32+64+2+htlcs*64 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let mut htlc_signatures = Vec::with_capacity(htlcs);
-               let secp_ctx = Secp256k1::without_caps();
-               for i in 0..htlcs {
-                       htlc_signatures.push(secp_signature!(&secp_ctx, &v[98+i*64..98+(i+1)*64]));
-               }
-               Ok(Self {
-                       channel_id,
-                       signature: secp_signature!(&secp_ctx, &v[32..96]),
-                       htlc_signatures,
-               })
-       }
-}
-impl MsgEncodable for CommitmentSigned {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32+64+2+self.htlc_signatures.len()*64);
-               res.extend_from_slice(&self.channel_id);
-               let secp_ctx = Secp256k1::without_caps();
-               res.extend_from_slice(&self.signature.serialize_compact(&secp_ctx));
-               res.extend_from_slice(&byte_utils::be16_to_array(self.htlc_signatures.len() as u16));
-               for i in 0..self.htlc_signatures.len() {
-                       res.extend_from_slice(&self.htlc_signatures[i].serialize_compact(&secp_ctx));
-               }
-               res
-       }
-}
-
-impl MsgDecodable for RevokeAndACK {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+32+33 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-               let mut per_commitment_secret = [0; 32];
-               per_commitment_secret.copy_from_slice(&v[32..64]);
-               let secp_ctx = Secp256k1::without_caps();
-               Ok(Self {
-                       channel_id,
-                       per_commitment_secret,
-                       next_per_commitment_point: secp_pubkey!(&secp_ctx, &v[64..97]),
-               })
-       }
-}
-impl MsgEncodable for RevokeAndACK {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32+32+33);
-               res.extend_from_slice(&self.channel_id);
-               res.extend_from_slice(&self.per_commitment_secret);
-               res.extend_from_slice(&self.next_per_commitment_point.serialize());
-               res
-       }
-}
-
-impl MsgDecodable for UpdateFee {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+4 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-               Ok(Self {
-                       channel_id,
-                       feerate_per_kw: byte_utils::slice_to_be32(&v[32..36]),
-               })
-       }
-}
-impl MsgEncodable for UpdateFee {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32+4);
-               res.extend_from_slice(&self.channel_id);
-               res.extend_from_slice(&byte_utils::be32_to_array(self.feerate_per_kw));
-               res
-       }
-}
-
-impl MsgDecodable for ChannelReestablish {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+2*8 {
-                       return Err(DecodeError::ShortRead);
-               }
-
-               let data_loss_protect = if v.len() > 32+2*8 {
-                       if v.len() < 32+2*8 + 33+32 {
-                               return Err(DecodeError::ShortRead);
-                       }
-                       let mut inner_array = [0; 32];
-                       inner_array.copy_from_slice(&v[48..48+32]);
-                       Some(DataLossProtect {
-                               your_last_per_commitment_secret: inner_array,
-                               my_current_per_commitment_point: secp_pubkey!(&Secp256k1::without_caps(), &v[48+32..48+32+33]),
-                       })
-               } else { None };
-
-               Ok(Self {
-                       channel_id: deserialize(&v[0..32]).unwrap(),
-                       next_local_commitment_number: byte_utils::slice_to_be64(&v[32..40]),
-                       next_remote_commitment_number: byte_utils::slice_to_be64(&v[40..48]),
-                       data_loss_protect: data_loss_protect,
-               })
-       }
-}
-impl MsgEncodable for ChannelReestablish {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(if self.data_loss_protect.is_some() { 32+2*8+33+32 } else { 32+2*8 });
-
-               res.extend_from_slice(&serialize(&self.channel_id).unwrap()[..]);
-               res.extend_from_slice(&byte_utils::be64_to_array(self.next_local_commitment_number));
-               res.extend_from_slice(&byte_utils::be64_to_array(self.next_remote_commitment_number));
-
-               if let &Some(ref data_loss_protect) = &self.data_loss_protect {
-                       res.extend_from_slice(&data_loss_protect.your_last_per_commitment_secret[..]);
-                       res.extend_from_slice(&data_loss_protect.my_current_per_commitment_point.serialize());
-               }
-               res
-       }
-}
-
-impl MsgDecodable for AnnouncementSignatures {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+8+64*2 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let secp_ctx = Secp256k1::without_caps();
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-               Ok(Self {
-                       channel_id,
-                       short_channel_id: byte_utils::slice_to_be64(&v[32..40]),
-                       node_signature: secp_signature!(&secp_ctx, &v[40..104]),
-                       bitcoin_signature: secp_signature!(&secp_ctx, &v[104..168]),
-               })
-       }
-}
-impl MsgEncodable for AnnouncementSignatures {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32+8+64*2);
-               res.extend_from_slice(&self.channel_id);
-               res.extend_from_slice(&byte_utils::be64_to_array(self.short_channel_id));
-               let secp_ctx = Secp256k1::without_caps();
-               res.extend_from_slice(&self.node_signature.serialize_compact(&secp_ctx));
-               res.extend_from_slice(&self.bitcoin_signature.serialize_compact(&secp_ctx));
-               res
-       }
-}
-
-impl MsgDecodable for UnsignedNodeAnnouncement {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               let features = GlobalFeatures::decode(&v[..])?;
-               if features.requires_unknown_bits() {
-                       return Err(DecodeError::UnknownRequiredFeature);
-               }
-
-               if v.len() < features.encoded_len() + 4 + 33 + 3 + 32 + 2 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let start = features.encoded_len();
-
-               let mut rgb = [0; 3];
-               rgb.copy_from_slice(&v[start + 37..start + 40]);
-
-               let mut alias = [0; 32];
-               alias.copy_from_slice(&v[start + 40..start + 72]);
-
-               let addrlen = byte_utils::slice_to_be16(&v[start + 72..start + 74]) as usize;
-               if v.len() < start + 74 + addrlen {
-                       return Err(DecodeError::ShortRead);
-               }
-               let addr_read_limit = start + 74 + addrlen;
-
-               let mut addresses = Vec::with_capacity(4);
-               let mut read_pos = start + 74;
-               loop {
-                       if addr_read_limit <= read_pos { break; }
-                       match v[read_pos] {
-                               1 => {
-                                       if addresses.len() > 0 {
-                                               return Err(DecodeError::ExtraAddressesPerType);
-                                       }
-                                       if addr_read_limit < read_pos + 1 + 6 {
-                                               return Err(DecodeError::BadLengthDescriptor);
-                                       }
-                                       let mut addr = [0; 4];
-                                       addr.copy_from_slice(&v[read_pos + 1..read_pos + 5]);
-                                       addresses.push(NetAddress::IPv4 {
-                                               addr,
-                                               port: byte_utils::slice_to_be16(&v[read_pos + 5..read_pos + 7]),
-                                       });
-                                       read_pos += 1 + 6;
-                               },
-                               2 => {
-                                       if addresses.len() > 1 || (addresses.len() == 1 && addresses[0].get_id() != 1) {
-                                               return Err(DecodeError::ExtraAddressesPerType);
-                                       }
-                                       if addr_read_limit < read_pos + 1 + 18 {
-                                               return Err(DecodeError::BadLengthDescriptor);
-                                       }
-                                       let mut addr = [0; 16];
-                                       addr.copy_from_slice(&v[read_pos + 1..read_pos + 17]);
-                                       addresses.push(NetAddress::IPv6 {
-                                               addr,
-                                               port: byte_utils::slice_to_be16(&v[read_pos + 17..read_pos + 19]),
-                                       });
-                                       read_pos += 1 + 18;
-                               },
-                               3 => {
-                                       if addresses.len() > 2 || (addresses.len() > 0 && addresses.last().unwrap().get_id() > 2) {
-                                               return Err(DecodeError::ExtraAddressesPerType);
-                                       }
-                                       if addr_read_limit < read_pos + 1 + 12 {
-                                               return Err(DecodeError::BadLengthDescriptor);
-                                       }
-                                       let mut addr = [0; 10];
-                                       addr.copy_from_slice(&v[read_pos + 1..read_pos + 11]);
-                                       addresses.push(NetAddress::OnionV2 {
-                                               addr,
-                                               port: byte_utils::slice_to_be16(&v[read_pos + 11..read_pos + 13]),
-                                       });
-                                       read_pos += 1 + 12;
-                               },
-                               4 => {
-                                       if addresses.len() > 3 || (addresses.len() > 0 && addresses.last().unwrap().get_id() > 3) {
-                                               return Err(DecodeError::ExtraAddressesPerType);
-                                       }
-                                       if addr_read_limit < read_pos + 1 + 37 {
-                                               return Err(DecodeError::BadLengthDescriptor);
-                                       }
-                                       let mut ed25519_pubkey = [0; 32];
-                                       ed25519_pubkey.copy_from_slice(&v[read_pos + 1..read_pos + 33]);
-                                       addresses.push(NetAddress::OnionV3 {
-                                               ed25519_pubkey,
-                                               checksum: byte_utils::slice_to_be16(&v[read_pos + 33..read_pos + 35]),
-                                               version: v[read_pos + 35],
-                                               port: byte_utils::slice_to_be16(&v[read_pos + 36..read_pos + 38]),
-                                       });
-                                       read_pos += 1 + 37;
-                               },
-                               _ => { break; } // We've read all we can, we dont understand anything higher (and they're sorted)
-                       }
-               }
-
-               let excess_address_data = if read_pos < addr_read_limit {
-                       let mut excess_address_data = Vec::with_capacity(addr_read_limit - read_pos);
-                       excess_address_data.extend_from_slice(&v[read_pos..addr_read_limit]);
-                       excess_address_data
-               } else { Vec::new() };
-
-               let mut excess_data = Vec::with_capacity(v.len() - addr_read_limit);
-               excess_data.extend_from_slice(&v[addr_read_limit..]);
-
-               let secp_ctx = Secp256k1::without_caps();
-               Ok(Self {
-                       features,
-                       timestamp: byte_utils::slice_to_be32(&v[start..start + 4]),
-                       node_id: secp_pubkey!(&secp_ctx, &v[start + 4..start + 37]),
-                       rgb,
-                       alias,
-                       addresses,
-                       excess_address_data,
-                       excess_data,
-               })
-       }
-}
-impl MsgEncodable for UnsignedNodeAnnouncement {
-       fn encode(&self) -> Vec<u8> {
-               let features = self.features.encode();
-               let mut res = Vec::with_capacity(74 + features.len() + self.addresses.len()*7 + self.excess_address_data.len() + self.excess_data.len());
-               res.extend_from_slice(&features[..]);
-               res.extend_from_slice(&byte_utils::be32_to_array(self.timestamp));
-               res.extend_from_slice(&self.node_id.serialize());
-               res.extend_from_slice(&self.rgb);
-               res.extend_from_slice(&self.alias);
-               let mut addr_slice = Vec::with_capacity(self.addresses.len() * 18);
-               let mut addrs_to_encode = self.addresses.clone();
-               addrs_to_encode.sort_unstable_by(|a, b| { a.get_id().cmp(&b.get_id()) });
-               addrs_to_encode.dedup_by(|a, b| { a.get_id() == b.get_id() });
-               for addr in addrs_to_encode.iter() {
-                       match addr {
-                               &NetAddress::IPv4{addr, port} => {
-                                       addr_slice.push(1);
-                                       addr_slice.extend_from_slice(&addr);
-                                       addr_slice.extend_from_slice(&byte_utils::be16_to_array(port));
-                               },
-                               &NetAddress::IPv6{addr, port} => {
-                                       addr_slice.push(2);
-                                       addr_slice.extend_from_slice(&addr);
-                                       addr_slice.extend_from_slice(&byte_utils::be16_to_array(port));
-                               },
-                               &NetAddress::OnionV2{addr, port} => {
-                                       addr_slice.push(3);
-                                       addr_slice.extend_from_slice(&addr);
-                                       addr_slice.extend_from_slice(&byte_utils::be16_to_array(port));
-                               },
-                               &NetAddress::OnionV3{ed25519_pubkey, checksum, version, port} => {
-                                       addr_slice.push(4);
-                                       addr_slice.extend_from_slice(&ed25519_pubkey);
-                                       addr_slice.extend_from_slice(&byte_utils::be16_to_array(checksum));
-                                       addr_slice.push(version);
-                                       addr_slice.extend_from_slice(&byte_utils::be16_to_array(port));
-                               },
-                       }
-               }
-               res.extend_from_slice(&byte_utils::be16_to_array((addr_slice.len() + self.excess_address_data.len()) as u16));
-               res.extend_from_slice(&addr_slice[..]);
-               res.extend_from_slice(&self.excess_address_data[..]);
-               res.extend_from_slice(&self.excess_data[..]);
-               res
-       }
-}
-
-impl MsgDecodable for NodeAnnouncement {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 64 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let secp_ctx = Secp256k1::without_caps();
-               Ok(Self {
-                       signature: secp_signature!(&secp_ctx, &v[0..64]),
-                       contents: UnsignedNodeAnnouncement::decode(&v[64..])?,
-               })
-       }
-}
-impl MsgEncodable for NodeAnnouncement {
-       fn encode(&self) -> Vec<u8> {
-               let contents = self.contents.encode();
-               let mut res = Vec::with_capacity(64 + contents.len());
-               let secp_ctx = Secp256k1::without_caps();
-               res.extend_from_slice(&self.signature.serialize_compact(&secp_ctx));
-               res.extend_from_slice(&contents);
-               res
-       }
-}
-
-impl MsgDecodable for UnsignedChannelAnnouncement {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               let features = GlobalFeatures::decode(&v[..])?;
-               if features.requires_unknown_bits() {
-                       return Err(DecodeError::UnknownRequiredFeature);
-               }
-               if v.len() < features.encoded_len() + 32 + 8 + 33*4 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let start = features.encoded_len();
-               let secp_ctx = Secp256k1::without_caps();
-               let mut excess_data = Vec::with_capacity(v.len() - start - 172);
-               excess_data.extend_from_slice(&v[start + 172..]);
-               Ok(Self {
-                       features,
-                       chain_hash: deserialize(&v[start..start + 32]).unwrap(),
-                       short_channel_id: byte_utils::slice_to_be64(&v[start + 32..start + 40]),
-                       node_id_1: secp_pubkey!(&secp_ctx, &v[start + 40..start + 73]),
-                       node_id_2: secp_pubkey!(&secp_ctx, &v[start + 73..start + 106]),
-                       bitcoin_key_1: secp_pubkey!(&secp_ctx, &v[start + 106..start + 139]),
-                       bitcoin_key_2: secp_pubkey!(&secp_ctx, &v[start + 139..start + 172]),
-                       excess_data,
-               })
-       }
-}
-impl MsgEncodable for UnsignedChannelAnnouncement {
-       fn encode(&self) -> Vec<u8> {
-               let features = self.features.encode();
-               let mut res = Vec::with_capacity(172 + features.len() + self.excess_data.len());
-               res.extend_from_slice(&features[..]);
-               res.extend_from_slice(&self.chain_hash[..]);
-               res.extend_from_slice(&byte_utils::be64_to_array(self.short_channel_id));
-               res.extend_from_slice(&self.node_id_1.serialize());
-               res.extend_from_slice(&self.node_id_2.serialize());
-               res.extend_from_slice(&self.bitcoin_key_1.serialize());
-               res.extend_from_slice(&self.bitcoin_key_2.serialize());
-               res.extend_from_slice(&self.excess_data[..]);
-               res
-       }
-}
-
-impl MsgDecodable for ChannelAnnouncement {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 64*4 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let secp_ctx = Secp256k1::without_caps();
-               Ok(Self {
-                       node_signature_1: secp_signature!(&secp_ctx, &v[0..64]),
-                       node_signature_2: secp_signature!(&secp_ctx, &v[64..128]),
-                       bitcoin_signature_1: secp_signature!(&secp_ctx, &v[128..192]),
-                       bitcoin_signature_2: secp_signature!(&secp_ctx, &v[192..256]),
-                       contents: UnsignedChannelAnnouncement::decode(&v[256..])?,
-               })
-       }
-}
-impl MsgEncodable for ChannelAnnouncement {
-       fn encode(&self) -> Vec<u8> {
-               let secp_ctx = Secp256k1::without_caps();
-               let contents = self.contents.encode();
-               let mut res = Vec::with_capacity(64 + contents.len());
-               res.extend_from_slice(&self.node_signature_1.serialize_compact(&secp_ctx));
-               res.extend_from_slice(&self.node_signature_2.serialize_compact(&secp_ctx));
-               res.extend_from_slice(&self.bitcoin_signature_1.serialize_compact(&secp_ctx));
-               res.extend_from_slice(&self.bitcoin_signature_2.serialize_compact(&secp_ctx));
-               res.extend_from_slice(&contents);
-               res
-       }
-}
-
-impl MsgDecodable for UnsignedChannelUpdate {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32+8+4+2+2+8+4+4 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let mut excess_data = Vec::with_capacity(v.len() - 64);
-               excess_data.extend_from_slice(&v[64..]);
-               Ok(Self {
-                       chain_hash: deserialize(&v[0..32]).unwrap(),
-                       short_channel_id: byte_utils::slice_to_be64(&v[32..40]),
-                       timestamp: byte_utils::slice_to_be32(&v[40..44]),
-                       flags: byte_utils::slice_to_be16(&v[44..46]),
-                       cltv_expiry_delta: byte_utils::slice_to_be16(&v[46..48]),
-                       htlc_minimum_msat: byte_utils::slice_to_be64(&v[48..56]),
-                       fee_base_msat: byte_utils::slice_to_be32(&v[56..60]),
-                       fee_proportional_millionths: byte_utils::slice_to_be32(&v[60..64]),
-                       excess_data
-               })
-       }
-}
-impl MsgEncodable for UnsignedChannelUpdate {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(64 + self.excess_data.len());
-               res.extend_from_slice(&self.chain_hash[..]);
-               res.extend_from_slice(&byte_utils::be64_to_array(self.short_channel_id));
-               res.extend_from_slice(&byte_utils::be32_to_array(self.timestamp));
-               res.extend_from_slice(&byte_utils::be16_to_array(self.flags));
-               res.extend_from_slice(&byte_utils::be16_to_array(self.cltv_expiry_delta));
-               res.extend_from_slice(&byte_utils::be64_to_array(self.htlc_minimum_msat));
-               res.extend_from_slice(&byte_utils::be32_to_array(self.fee_base_msat));
-               res.extend_from_slice(&byte_utils::be32_to_array(self.fee_proportional_millionths));
-               res.extend_from_slice(&self.excess_data[..]);
-               res
-       }
-}
-
-impl MsgDecodable for ChannelUpdate {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 128 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let secp_ctx = Secp256k1::without_caps();
-               Ok(Self {
-                       signature: secp_signature!(&secp_ctx, &v[0..64]),
-                       contents: UnsignedChannelUpdate::decode(&v[64..])?,
-               })
-       }
-}
-impl MsgEncodable for ChannelUpdate {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(128);
-               res.extend_from_slice(&self.signature.serialize_compact(&Secp256k1::without_caps())[..]);
-               res.extend_from_slice(&self.contents.encode()[..]);
-               res
-       }
-}
-
-impl MsgDecodable for OnionRealm0HopData {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32 {
-                       return Err(DecodeError::ShortRead);
-               }
-               Ok(OnionRealm0HopData {
-                       short_channel_id: byte_utils::slice_to_be64(&v[0..8]),
-                       amt_to_forward: byte_utils::slice_to_be64(&v[8..16]),
-                       outgoing_cltv_value: byte_utils::slice_to_be32(&v[16..20]),
-               })
-       }
-}
-impl MsgEncodable for OnionRealm0HopData {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32);
-               res.extend_from_slice(&byte_utils::be64_to_array(self.short_channel_id));
-               res.extend_from_slice(&byte_utils::be64_to_array(self.amt_to_forward));
-               res.extend_from_slice(&byte_utils::be32_to_array(self.outgoing_cltv_value));
-               res.resize(32, 0);
-               res
-       }
-}
-
-impl MsgDecodable for OnionHopData {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 65 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let realm = v[0];
-               if realm != 0 {
-                       return Err(DecodeError::UnknownRealmByte);
-               }
-               let mut hmac = [0; 32];
-               hmac[..].copy_from_slice(&v[33..65]);
-               Ok(OnionHopData {
-                       realm: realm,
-                       data: OnionRealm0HopData::decode(&v[1..33])?,
-                       hmac: hmac,
-               })
-       }
-}
-impl MsgEncodable for OnionHopData {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(65);
-               res.push(self.realm);
-               res.extend_from_slice(&self.data.encode()[..]);
-               res.extend_from_slice(&self.hmac);
-               res
-       }
-}
-
-impl MsgDecodable for OnionPacket {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 1+33+20*65+32 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let mut hop_data = [0; 20*65];
-               hop_data.copy_from_slice(&v[34..1334]);
-               let mut hmac = [0; 32];
-               hmac.copy_from_slice(&v[1334..1366]);
-               let secp_ctx = Secp256k1::without_caps();
-               Ok(Self {
-                       version: v[0],
-                       public_key: PublicKey::from_slice(&secp_ctx, &v[1..34]),
-                       hop_data,
-                       hmac,
-               })
-       }
-}
-impl MsgEncodable for OnionPacket {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(1 + 33 + 20*65 + 32);
-               res.push(self.version);
-               match self.public_key {
-                       Ok(pubkey) => res.extend_from_slice(&pubkey.serialize()),
-                       Err(_) => res.extend_from_slice(&[0; 33]),
-               }
-               res.extend_from_slice(&self.hop_data);
-               res.extend_from_slice(&self.hmac);
-               res
-       }
-}
-
-impl MsgDecodable for DecodedOnionErrorPacket {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 32 + 4 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let failuremsg_len = byte_utils::slice_to_be16(&v[32..34]) as usize;
-               if v.len() < 32 + 4 + failuremsg_len {
-                       return Err(DecodeError::ShortRead);
-               }
-               let padding_len = byte_utils::slice_to_be16(&v[34 + failuremsg_len..]) as usize;
-               if v.len() < 32 + 4 + failuremsg_len + padding_len {
-                       return Err(DecodeError::ShortRead);
-               }
-
-               let mut hmac = [0; 32];
-               hmac.copy_from_slice(&v[0..32]);
-               Ok(Self {
-                       hmac,
-                       failuremsg: v[34..34 + failuremsg_len].to_vec(),
-                       pad: v[36 + failuremsg_len..36 + failuremsg_len + padding_len].to_vec(),
-               })
-       }
-}
-impl MsgEncodable for DecodedOnionErrorPacket {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(32 + 4 + self.failuremsg.len() + self.pad.len());
-               res.extend_from_slice(&self.hmac);
-               res.extend_from_slice(&[((self.failuremsg.len() >> 8) & 0xff) as u8, (self.failuremsg.len() & 0xff) as u8]);
-               res.extend_from_slice(&self.failuremsg);
-               res.extend_from_slice(&[((self.pad.len() >> 8) & 0xff) as u8, (self.pad.len() & 0xff) as u8]);
-               res.extend_from_slice(&self.pad);
-               res
-       }
-}
-
-impl MsgDecodable for OnionErrorPacket {
-       fn decode(v: &[u8]) -> Result<Self, DecodeError> {
-               if v.len() < 2 {
-                       return Err(DecodeError::ShortRead);
-               }
-               let len = byte_utils::slice_to_be16(&v[0..2]) as usize;
-               if v.len() < 2 + len {
-                       return Err(DecodeError::ShortRead);
-               }
-               Ok(Self {
-                       data: v[2..len+2].to_vec(),
-               })
-       }
-}
-impl MsgEncodable for OnionErrorPacket {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(2 + self.data.len());
-               res.extend_from_slice(&byte_utils::be16_to_array(self.data.len() as u16));
-               res.extend_from_slice(&self.data);
-               res
-       }
-}
-
-impl MsgEncodable for ErrorMessage {
-       fn encode(&self) -> Vec<u8> {
-               let mut res = Vec::with_capacity(34 + self.data.len());
-               res.extend_from_slice(&self.channel_id);
-               res.extend_from_slice(&byte_utils::be16_to_array(self.data.len() as u16));
-               res.extend_from_slice(&self.data.as_bytes());
-               res
-       }
-}
-impl MsgDecodable for ErrorMessage {
-       fn decode(v: &[u8]) -> Result<Self,DecodeError> {
-               if v.len() < 34 {
-                       return Err(DecodeError::ShortRead);
-               }
-               // Unlike most messages, BOLT 1 requires we truncate our read if the value is out of range
-               let len = cmp::min(byte_utils::slice_to_be16(&v[32..34]) as usize, v.len() - 34);
-               let data = match String::from_utf8(v[34..34 + len].to_vec()) {
-                       Ok(s) => s,
-                       Err(_) => return Err(DecodeError::BadText),
-               };
-               let mut channel_id = [0; 32];
-               channel_id[..].copy_from_slice(&v[0..32]);
-               Ok(Self {
-                       channel_id,
-                       data,
-               })
-       }
-}
-
-impl_writeable!(AcceptChannel, {
+impl_writeable_len_match!(AcceptChannel, {
+               {AcceptChannel{ shutdown_scriptpubkey: Some(ref script), ..}, 270 + 2 + script.len()},
+               {_, 270}
+       }, {
        temporary_channel_id,
        dust_limit_satoshis,
        max_htlc_value_in_flight_msat,
@@ -1717,15 +560,16 @@ impl_writeable!(AcceptChannel, {
        shutdown_scriptpubkey
 });
 
-impl_writeable!(AnnouncementSignatures, {
+impl_writeable!(AnnouncementSignatures, 32+8+64*2, {
        channel_id,
        short_channel_id,
        node_signature,
        bitcoin_signature
 });
 
-impl<W: ::std::io::Write> Writeable<W> for ChannelReestablish {
-       fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
+impl Writeable for ChannelReestablish {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+               w.size_hint(if self.data_loss_protect.is_some() { 32+2*8+33+32 } else { 32+2*8 });
                self.channel_id.write(w)?;
                self.next_local_commitment_number.write(w)?;
                self.next_remote_commitment_number.write(w)?;
@@ -1737,8 +581,8 @@ impl<W: ::std::io::Write> Writeable<W> for ChannelReestablish {
        }
 }
 
-impl<R: ::std::io::Read> Readable<R> for ChannelReestablish{
-       fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
+impl<R: Read> Readable<R> for ChannelReestablish{
+       fn read(r: &mut R) -> Result<Self, DecodeError> {
                Ok(Self {
                        channel_id: Readable::read(r)?,
                        next_local_commitment_number: Readable::read(r)?,
@@ -1758,55 +602,68 @@ impl<R: ::std::io::Read> Readable<R> for ChannelReestablish{
        }
 }
 
-impl_writeable!(ClosingSigned, {
+impl_writeable!(ClosingSigned, 32+8+64, {
        channel_id,
        fee_satoshis,
        signature
 });
 
-impl_writeable!(CommitmentSigned, {
+impl_writeable_len_match!(CommitmentSigned, {
+               { CommitmentSigned { ref htlc_signatures, .. }, 32+64+2+htlc_signatures.len()*64 }
+       }, {
        channel_id,
        signature,
        htlc_signatures
 });
 
-impl_writeable!(DecodedOnionErrorPacket, {
+impl_writeable_len_match!(DecodedOnionErrorPacket, {
+               { DecodedOnionErrorPacket { ref failuremsg, ref pad, .. }, 32 + 4 + failuremsg.len() + pad.len() }
+       }, {
        hmac,
        failuremsg,
        pad
 });
 
-impl_writeable!(FundingCreated, {
+impl_writeable!(FundingCreated, 32+32+2+64, {
        temporary_channel_id,
        funding_txid,
        funding_output_index,
        signature
 });
 
-impl_writeable!(FundingSigned, {
+impl_writeable!(FundingSigned, 32+64, {
        channel_id,
        signature
 });
 
-impl_writeable!(FundingLocked, {
+impl_writeable!(FundingLocked, 32+33, {
        channel_id,
        next_per_commitment_point
 });
 
-impl_writeable!(GlobalFeatures, {
+impl_writeable_len_match!(GlobalFeatures, {
+               { GlobalFeatures { ref flags }, flags.len() + 2 }
+       }, {
        flags
 });
 
-impl_writeable!(LocalFeatures, {
+impl_writeable_len_match!(LocalFeatures, {
+               { LocalFeatures { ref flags }, flags.len() + 2 }
+       }, {
        flags
 });
 
-impl_writeable!(Init, {
+impl_writeable_len_match!(Init, {
+               { Init { ref global_features, ref local_features }, global_features.flags.len() + local_features.flags.len() + 4 }
+       }, {
        global_features,
        local_features
 });
 
-impl_writeable!(OpenChannel, {
+impl_writeable_len_match!(OpenChannel, {
+               { OpenChannel { shutdown_scriptpubkey: Some(ref script), .. }, 319 + 2 + script.len() },
+               { OpenChannel { shutdown_scriptpubkey: None, .. }, 319 }
+       }, {
        chain_hash,
        temporary_channel_id,
        funding_satoshis,
@@ -1828,47 +685,54 @@ impl_writeable!(OpenChannel, {
        shutdown_scriptpubkey
 });
 
-impl_writeable!(RevokeAndACK, {
+impl_writeable!(RevokeAndACK, 32+32+33, {
        channel_id,
        per_commitment_secret,
        next_per_commitment_point
 });
 
-impl_writeable!(Shutdown, {
+impl_writeable_len_match!(Shutdown, {
+               { Shutdown { ref scriptpubkey, .. }, 32 + 2 + scriptpubkey.len() }
+       }, {
        channel_id,
        scriptpubkey
 });
 
-impl_writeable!(UpdateFailHTLC, {
+impl_writeable_len_match!(UpdateFailHTLC, {
+               { UpdateFailHTLC { ref reason, .. }, 32 + 10 + reason.data.len() }
+       }, {
        channel_id,
        htlc_id,
        reason
 });
 
-impl_writeable!(UpdateFailMalformedHTLC, {
+impl_writeable!(UpdateFailMalformedHTLC, 32+8+32+2, {
        channel_id,
        htlc_id,
        sha256_of_onion,
        failure_code
 });
 
-impl_writeable!(UpdateFee, {
+impl_writeable!(UpdateFee, 32+4, {
        channel_id,
        feerate_per_kw
 });
 
-impl_writeable!(UpdateFulfillHTLC, {
+impl_writeable!(UpdateFulfillHTLC, 32+8+32, {
        channel_id,
        htlc_id,
        payment_preimage
 });
 
-impl_writeable!(OnionErrorPacket, {
+impl_writeable_len_match!(OnionErrorPacket, {
+               { OnionErrorPacket { ref data, .. }, 2 + data.len() }
+       }, {
        data
 });
 
-impl<W: ::std::io::Write> Writeable<W> for OnionPacket {
-       fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
+impl Writeable for OnionPacket {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+               w.size_hint(1 + 33 + 20*65 + 32);
                self.version.write(w)?;
                match self.public_key {
                        Ok(pubkey) => pubkey.write(w)?,
@@ -1880,8 +744,8 @@ impl<W: ::std::io::Write> Writeable<W> for OnionPacket {
        }
 }
 
-impl<R: ::std::io::Read> Readable<R> for OnionPacket {
-       fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
+impl<R: Read> Readable<R> for OnionPacket {
+       fn read(r: &mut R) -> Result<Self, DecodeError> {
                Ok(OnionPacket {
                        version: Readable::read(r)?,
                        public_key: {
@@ -1895,7 +759,7 @@ impl<R: ::std::io::Read> Readable<R> for OnionPacket {
        }
 }
 
-impl_writeable!(UpdateAddHTLC, {
+impl_writeable!(UpdateAddHTLC, 32+8+8+32+4+1366, {
        channel_id,
        htlc_id,
        amount_msat,
@@ -1904,8 +768,9 @@ impl_writeable!(UpdateAddHTLC, {
        onion_routing_packet
 });
 
-impl<W: ::std::io::Write> Writeable<W> for OnionRealm0HopData {
-       fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
+impl Writeable for OnionRealm0HopData {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+               w.size_hint(32);
                self.short_channel_id.write(w)?;
                self.amt_to_forward.write(w)?;
                self.outgoing_cltv_value.write(w)?;
@@ -1914,8 +779,8 @@ impl<W: ::std::io::Write> Writeable<W> for OnionRealm0HopData {
        }
 }
 
-impl<R: ::std::io::Read> Readable<R> for OnionRealm0HopData {
-       fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
+impl<R: Read> Readable<R> for OnionRealm0HopData {
+       fn read(r: &mut R) -> Result<Self, DecodeError> {
                Ok(OnionRealm0HopData {
                        short_channel_id: Readable::read(r)?,
                        amt_to_forward: Readable::read(r)?,
@@ -1928,8 +793,9 @@ impl<R: ::std::io::Read> Readable<R> for OnionRealm0HopData {
        }
 }
 
-impl<W: ::std::io::Write> Writeable<W> for OnionHopData {
-       fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
+impl Writeable for OnionHopData {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+               w.size_hint(65);
                self.realm.write(w)?;
                self.data.write(w)?;
                self.hmac.write(w)?;
@@ -1937,8 +803,8 @@ impl<W: ::std::io::Write> Writeable<W> for OnionHopData {
        }
 }
 
-impl<R: ::std::io::Read> Readable<R> for OnionHopData {
-       fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
+impl<R: Read> Readable<R> for OnionHopData {
+       fn read(r: &mut R) -> Result<Self, DecodeError> {
                Ok(OnionHopData {
                        realm: {
                                let r: u8 = Readable::read(r)?;
@@ -1953,16 +819,17 @@ impl<R: ::std::io::Read> Readable<R> for OnionHopData {
        }
 }
 
-impl<W: ::std::io::Write> Writeable<W> for Ping {
-       fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
+impl Writeable for Ping {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+               w.size_hint(self.byteslen as usize + 4);
                self.ponglen.write(w)?;
                vec![0u8; self.byteslen as usize].write(w)?; // size-unchecked write
                Ok(())
        }
 }
 
-impl<R: ::std::io::Read> Readable<R> for Ping {
-       fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
+impl<R: Read> Readable<R> for Ping {
+       fn read(r: &mut R) -> Result<Self, DecodeError> {
                Ok(Ping {
                        ponglen: Readable::read(r)?,
                        byteslen: {
@@ -1974,15 +841,16 @@ impl<R: ::std::io::Read> Readable<R> for Ping {
        }
 }
 
-impl<W: ::std::io::Write> Writeable<W> for Pong {
-       fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
+impl Writeable for Pong {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+               w.size_hint(self.byteslen as usize + 2);
                vec![0u8; self.byteslen as usize].write(w)?; // size-unchecked write
                Ok(())
        }
 }
 
-impl<R: ::std::io::Read> Readable<R> for Pong {
-       fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
+impl<R: Read> Readable<R> for Pong {
+       fn read(r: &mut R) -> Result<Self, DecodeError> {
                Ok(Pong {
                        byteslen: {
                                let byteslen = Readable::read(r)?;
@@ -1993,8 +861,9 @@ impl<R: ::std::io::Read> Readable<R> for Pong {
        }
 }
 
-impl<W: ::std::io::Write> Writeable<W> for UnsignedChannelAnnouncement {
-       fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
+impl Writeable for UnsignedChannelAnnouncement {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+               w.size_hint(2 + 2*32 + 4*33 + self.features.flags.len() + self.excess_data.len());
                self.features.write(w)?;
                self.chain_hash.write(w)?;
                self.short_channel_id.write(w)?;
@@ -2007,8 +876,8 @@ impl<W: ::std::io::Write> Writeable<W> for UnsignedChannelAnnouncement {
        }
 }
 
-impl<R: ::std::io::Read> Readable<R> for UnsignedChannelAnnouncement {
-       fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
+impl<R: Read> Readable<R> for UnsignedChannelAnnouncement {
+       fn read(r: &mut R) -> Result<Self, DecodeError> {
                Ok(Self {
                        features: {
                                let f: GlobalFeatures = Readable::read(r)?;
@@ -2032,7 +901,10 @@ impl<R: ::std::io::Read> Readable<R> for UnsignedChannelAnnouncement {
        }
 }
 
-impl_writeable!(ChannelAnnouncement,{
+impl_writeable_len_match!(ChannelAnnouncement, {
+               { ChannelAnnouncement { contents: UnsignedChannelAnnouncement {ref features, ref excess_data, ..}, .. },
+                       2 + 2*32 + 4*33 + features.flags.len() + excess_data.len() + 4*64 }
+       }, {
        node_signature_1,
        node_signature_2,
        bitcoin_signature_1,
@@ -2040,8 +912,9 @@ impl_writeable!(ChannelAnnouncement,{
        contents
 });
 
-impl<W: ::std::io::Write> Writeable<W> for UnsignedChannelUpdate {
-       fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
+impl Writeable for UnsignedChannelUpdate {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+               w.size_hint(64 + self.excess_data.len());
                self.chain_hash.write(w)?;
                self.short_channel_id.write(w)?;
                self.timestamp.write(w)?;
@@ -2055,8 +928,8 @@ impl<W: ::std::io::Write> Writeable<W> for UnsignedChannelUpdate {
        }
 }
 
-impl<R: ::std::io::Read> Readable<R> for UnsignedChannelUpdate {
-       fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
+impl<R: Read> Readable<R> for UnsignedChannelUpdate {
+       fn read(r: &mut R) -> Result<Self, DecodeError> {
                Ok(Self {
                        chain_hash: Readable::read(r)?,
                        short_channel_id: Readable::read(r)?,
@@ -2075,21 +948,26 @@ impl<R: ::std::io::Read> Readable<R> for UnsignedChannelUpdate {
        }
 }
 
-impl_writeable!(ChannelUpdate, {
+impl_writeable_len_match!(ChannelUpdate, {
+               { ChannelUpdate { contents: UnsignedChannelUpdate {ref excess_data, ..}, .. },
+                       64 + excess_data.len() + 64 }
+       }, {
        signature,
        contents
 });
 
-impl<W: ::std::io::Write> Writeable<W> for ErrorMessage {
-       fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
+impl Writeable for ErrorMessage {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+               w.size_hint(32 + 2 + self.data.len());
                self.channel_id.write(w)?;
-               self.data.as_bytes().to_vec().write(w)?; // write with size prefix
+               (self.data.len() as u16).write(w)?;
+               w.write_all(self.data.as_bytes())?;
                Ok(())
        }
 }
 
-impl<R: ::std::io::Read> Readable<R> for ErrorMessage {
-       fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
+impl<R: Read> Readable<R> for ErrorMessage {
+       fn read(r: &mut R) -> Result<Self, DecodeError> {
                Ok(Self {
                        channel_id: Readable::read(r)?,
                        data: {
@@ -2106,8 +984,9 @@ impl<R: ::std::io::Read> Readable<R> for ErrorMessage {
        }
 }
 
-impl<W: ::std::io::Write> Writeable<W> for UnsignedNodeAnnouncement {
-       fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
+impl Writeable for UnsignedNodeAnnouncement {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+               w.size_hint(64 + 76 + self.features.flags.len() + self.addresses.len()*38 + self.excess_address_data.len() + self.excess_data.len());
                self.features.write(w)?;
                self.timestamp.write(w)?;
                self.node_id.write(w)?;
@@ -2152,8 +1031,8 @@ impl<W: ::std::io::Write> Writeable<W> for UnsignedNodeAnnouncement {
        }
 }
 
-impl<R: ::std::io::Read> Readable<R> for UnsignedNodeAnnouncement {
-       fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
+impl<R: Read> Readable<R> for UnsignedNodeAnnouncement {
+       fn read(r: &mut R) -> Result<Self, DecodeError> {
                let features: GlobalFeatures = Readable::read(r)?;
                if features.requires_unknown_bits() {
                        return Err(DecodeError::UnknownRequiredFeature);
@@ -2274,7 +1153,10 @@ impl<R: ::std::io::Read> Readable<R> for UnsignedNodeAnnouncement {
        }
 }
 
-impl_writeable!(NodeAnnouncement, {
+impl_writeable_len_match!(NodeAnnouncement, {
+               { NodeAnnouncement { contents: UnsignedNodeAnnouncement { ref features, ref addresses, ref excess_address_data, ref excess_data, ..}, .. },
+                       64 + 76 + features.flags.len() + addresses.len()*38 + excess_address_data.len() + excess_data.len() }
+       }, {
        signature,
        contents
 });
@@ -2282,8 +1164,8 @@ impl_writeable!(NodeAnnouncement, {
 #[cfg(test)]
 mod tests {
        use hex;
-       use ln::msgs::MsgEncodable;
        use ln::msgs;
+       use util::ser::Writeable;
        use secp256k1::key::{PublicKey,SecretKey};
        use secp256k1::Secp256k1;