X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Futil%2Fser.rs;h=b27cf4b348c3d98fc805dd7478dbe640910d80f4;hb=0dfcacd22c23f69b6526c9c6507d21427a2b7ccb;hp=5a68f7a5eb4164a43753630d4e7015b712ac2f37;hpb=7ec16e5ad152f903afaa72e27ee169f252edd6c9;p=rust-lightning

diff --git a/lightning/src/util/ser.rs b/lightning/src/util/ser.rs
index 5a68f7a5..b27cf4b3 100644
--- a/lightning/src/util/ser.rs
+++ b/lightning/src/util/ser.rs
@@ -1,36 +1,49 @@
+// This file is Copyright its original authors, visible in version control
+// history.
+//
+// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
+// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
+// You may not use this file except in accordance with one or both of these
+// licenses.
+
 //! A very simple serialization framework which is used to serialize/deserialize messages as well
 //! as ChannelsManagers and ChannelMonitors.
 
-use std::result::Result;
-use std::io::{Read, Write};
-use std::collections::HashMap;
-use std::hash::Hash;
-use std::sync::Mutex;
-use std::cmp;
+use prelude::*;
+use io::{self, Read, Write};
+use io_extras::{copy, sink};
+use core::hash::Hash;
+use sync::Mutex;
+use core::cmp;
 
-use secp256k1::Signature;
-use secp256k1::key::{PublicKey, SecretKey};
+use bitcoin::secp256k1::Signature;
+use bitcoin::secp256k1::key::{PublicKey, SecretKey};
+use bitcoin::secp256k1::constants::{PUBLIC_KEY_SIZE, SECRET_KEY_SIZE, COMPACT_SIGNATURE_SIZE};
 use bitcoin::blockdata::script::Script;
 use bitcoin::blockdata::transaction::{OutPoint, Transaction, TxOut};
 use bitcoin::consensus;
 use bitcoin::consensus::Encodable;
-use bitcoin_hashes::sha256d::Hash as Sha256dHash;
-use std::marker::Sized;
+use bitcoin::hashes::sha256d::Hash as Sha256dHash;
+use bitcoin::hash_types::{Txid, BlockHash};
+use core::marker::Sized;
 use ln::msgs::DecodeError;
-use ln::channelmanager::{PaymentPreimage, PaymentHash, PaymentSecret};
-use util::byte_utils;
+use ln::{PaymentPreimage, PaymentHash, PaymentSecret};
 
-use util::byte_utils::{be64_to_array, be48_to_array, be32_to_array, be16_to_array, slice_to_be16, slice_to_be32, slice_to_be48, slice_to_be64};
+use util::byte_utils::{be48_to_array, slice_to_be48};
 
-const MAX_BUF_SIZE: usize = 64 * 1024;
+/// serialization buffer size
+pub const MAX_BUF_SIZE: usize = 64 * 1024;
 
 /// A trait that is similar to std::io::Write but has one extra function which can be used to size
 /// buffers being written into.
 /// An impl is provided for any type that also impls std::io::Write which simply ignores size
 /// hints.
+///
+/// (C-not exported) as we only export serialization to/from byte arrays instead
 pub trait Writer {
 	/// Writes the given buf out. See std::io::Write::write_all for more
-	fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error>;
+	fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error>;
 	/// Hints that data of the given size is about the be written. This may not always be called
 	/// prior to data being written and may be safely ignored.
 	fn size_hint(&mut self, size: usize);
@@ -38,8 +51,8 @@ pub trait Writer {
 
 impl<W: Write> Writer for W {
 	#[inline]
-	fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error> {
-		<Self as ::std::io::Write>::write_all(self, buf)
+	fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
+		<Self as io::Write>::write_all(self, buf)
 	}
 	#[inline]
 	fn size_hint(&mut self, _size: usize) { }
@@ -47,24 +60,29 @@ impl<W: Write> Writer for W {
 
 pub(crate) struct WriterWriteAdaptor<'a, W: Writer + 'a>(pub &'a mut W);
 impl<'a, W: Writer + 'a> Write for WriterWriteAdaptor<'a, W> {
-	fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error> {
+	#[inline]
+	fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
 		self.0.write_all(buf)
 	}
-	fn write(&mut self, buf: &[u8]) -> Result<usize, ::std::io::Error> {
+	#[inline]
+	fn write(&mut self, buf: &[u8]) -> Result<usize, io::Error> {
 		self.0.write_all(buf)?;
 		Ok(buf.len())
 	}
-	fn flush(&mut self) -> Result<(), ::std::io::Error> {
+	#[inline]
+	fn flush(&mut self) -> Result<(), io::Error> {
 		Ok(())
 	}
 }
 
 pub(crate) struct VecWriter(pub Vec<u8>);
 impl Writer for VecWriter {
-	fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error> {
+	#[inline]
+	fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
 		self.0.extend_from_slice(buf);
 		Ok(())
 	}
+	#[inline]
 	fn size_hint(&mut self, size: usize) {
 		self.0.reserve_exact(size);
 	}
@@ -75,7 +93,7 @@ impl Writer for VecWriter {
 pub(crate) struct LengthCalculatingWriter(pub usize);
 impl Writer for LengthCalculatingWriter {
 	#[inline]
-	fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error> {
+	fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
 		self.0 += buf.len();
 		Ok(())
 	}
@@ -95,12 +113,14 @@ impl<R: Read> FixedLengthReader<R> {
 		Self { read, bytes_read: 0, total_bytes }
 	}
 
+	#[inline]
 	pub fn bytes_remain(&mut self) -> bool {
 		self.bytes_read != self.total_bytes
 	}
 
+	#[inline]
 	pub fn eat_remaining(&mut self) -> Result<(), DecodeError> {
-		::std::io::copy(self, &mut ::std::io::sink()).unwrap();
+		copy(self, &mut sink()).unwrap();
 		if self.bytes_read != self.total_bytes {
 			Err(DecodeError::ShortRead)
 		} else {
@@ -109,7 +129,8 @@ impl<R: Read> FixedLengthReader<R> {
 	}
 }
 impl<R: Read> Read for FixedLengthReader<R> {
-	fn read(&mut self, dest: &mut [u8]) -> Result<usize, ::std::io::Error> {
+	#[inline]
+	fn read(&mut self, dest: &mut [u8]) -> Result<usize, io::Error> {
 		if self.total_bytes == self.bytes_read {
 			Ok(0)
 		} else {
@@ -137,7 +158,8 @@ impl<R: Read> ReadTrackingReader<R> {
 	}
 }
 impl<R: Read> Read for ReadTrackingReader<R> {
-	fn read(&mut self, dest: &mut [u8]) -> Result<usize, ::std::io::Error> {
+	#[inline]
+	fn read(&mut self, dest: &mut [u8]) -> Result<usize, io::Error> {
 		match self.read.read(dest) {
 			Ok(0) => Ok(0),
 			Ok(len) => {
@@ -150,9 +172,11 @@ impl<R: Read> Read for ReadTrackingReader<R> {
 }
 
 /// A trait that various rust-lightning types implement allowing them to be written out to a Writer
+///
+/// (C-not exported) as we only export serialization to/from byte arrays instead
 pub trait Writeable {
 	/// Writes self out to the given Writer
-	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error>;
+	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error>;
 
 	/// Writes self out to a Vec<u8>
 	fn encode(&self) -> Vec<u8> {
@@ -167,16 +191,28 @@ pub trait Writeable {
 		0u16.write(&mut msg).unwrap();
 		self.write(&mut msg).unwrap();
 		let len = msg.0.len();
-		msg.0[..2].copy_from_slice(&byte_utils::be16_to_array(len as u16 - 2));
+		msg.0[..2].copy_from_slice(&(len as u16 - 2).to_be_bytes());
 		msg.0
 	}
+
+	/// Gets the length of this object after it has been serialized. This can be overridden to
+	/// optimize cases where we prepend an object with its length.
+	// Note that LLVM optimizes this away in most cases! Check that it isn't before you override!
+	#[inline]
+	fn serialized_length(&self) -> usize {
+		let mut len_calc = LengthCalculatingWriter(0);
+		self.write(&mut len_calc).expect("No in-memory data may fail to serialize");
+		len_calc.0
+	}
 }
 
 impl<'a, T: Writeable> Writeable for &'a T {
-	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> { (*self).write(writer) }
+	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { (*self).write(writer) }
 }
 
 /// A trait that various rust-lightning types implement allowing them to be read in from a Read
+///
+/// (C-not exported) as we only export serialization to/from byte arrays instead
 pub trait Readable
 	where Self: Sized
 {
@@ -186,6 +222,8 @@ pub trait Readable
 
 /// A trait that various higher-level rust-lightning types implement allowing them to be read in
 /// from a Read given some additional set of arguments which is required to deserialize.
+///
+/// (C-not exported) as we only export serialization to/from byte arrays instead
 pub trait ReadableArgs<P>
 	where Self: Sized
 {
@@ -194,6 +232,8 @@ pub trait ReadableArgs<P>
 }
 
 /// A trait that various rust-lightning types implement allowing them to (maybe) be read in from a Read
+///
+/// (C-not exported) as we only export serialization to/from byte arrays instead
 pub trait MaybeReadable
 	where Self: Sized
 {
@@ -201,10 +241,50 @@ pub trait MaybeReadable
 	fn read<R: Read>(reader: &mut R) -> Result<Option<Self>, DecodeError>;
 }
 
+pub(crate) struct OptionDeserWrapper<T: Readable>(pub Option<T>);
+impl<T: Readable> Readable for OptionDeserWrapper<T> {
+	#[inline]
+	fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
+		Ok(Self(Some(Readable::read(reader)?)))
+	}
+}
+
+/// Wrapper to write each element of a Vec with no length prefix
+pub(crate) struct VecWriteWrapper<'a, T: Writeable>(pub &'a Vec<T>);
+impl<'a, T: Writeable> Writeable for VecWriteWrapper<'a, T> {
+	#[inline]
+	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
+		for ref v in self.0.iter() {
+			v.write(writer)?;
+		}
+		Ok(())
+	}
+}
+
+/// Wrapper to read elements from a given stream until it reaches the end of the stream.
+pub(crate) struct VecReadWrapper<T: Readable>(pub Vec<T>);
+impl<T: Readable> Readable for VecReadWrapper<T> {
+	#[inline]
+	fn read<R: Read>(mut reader: &mut R) -> Result<Self, DecodeError> {
+		let mut values = Vec::new();
+		loop {
+			let mut track_read = ReadTrackingReader::new(&mut reader);
+			match Readable::read(&mut track_read) {
+				Ok(v) => { values.push(v); },
+				// If we failed to read any bytes at all, we reached the end of our TLV
+				// stream and have simply exhausted all entries.
+				Err(ref e) if e == &DecodeError::ShortRead && !track_read.have_read => break,
+				Err(e) => return Err(e),
+			}
+		}
+		Ok(Self(values))
+	}
+}
+
 pub(crate) struct U48(pub u64);
 impl Writeable for U48 {
 	#[inline]
-	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 		writer.write_all(&be48_to_array(self.0))
 	}
 }
@@ -227,7 +307,7 @@ impl Readable for U48 {
 pub(crate) struct BigSize(pub u64);
 impl Writeable for BigSize {
 	#[inline]
-	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 		match self.0 {
 			0...0xFC => {
 				(self.0 as u8).write(writer)
@@ -288,18 +368,18 @@ impl Readable for BigSize {
 pub(crate) struct HighZeroBytesDroppedVarInt<T>(pub T);
 
 macro_rules! impl_writeable_primitive {
-	($val_type:ty, $meth_write:ident, $len: expr, $meth_read:ident) => {
+	($val_type:ty, $len: expr) => {
 		impl Writeable for $val_type {
 			#[inline]
-			fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
-				writer.write_all(&$meth_write(*self))
+			fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
+				writer.write_all(&self.to_be_bytes())
 			}
 		}
 		impl Writeable for HighZeroBytesDroppedVarInt<$val_type> {
 			#[inline]
-			fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+			fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 				// Skip any full leading 0 bytes when writing (in BE):
-				writer.write_all(&$meth_write(self.0)[(self.0.leading_zeros()/8) as usize..$len])
+				writer.write_all(&self.0.to_be_bytes()[(self.0.leading_zeros()/8) as usize..$len])
 			}
 		}
 		impl Readable for $val_type {
@@ -307,7 +387,7 @@ macro_rules! impl_writeable_primitive {
 			fn read<R: Read>(reader: &mut R) -> Result<$val_type, DecodeError> {
 				let mut buf = [0; $len];
 				reader.read_exact(&mut buf)?;
-				Ok($meth_read(&buf))
+				Ok(<$val_type>::from_be_bytes(buf))
 			}
 		}
 		impl Readable for HighZeroBytesDroppedVarInt<$val_type> {
@@ -326,7 +406,9 @@ macro_rules! impl_writeable_primitive {
 				}
 				if total_read_len == 0 || buf[$len] != 0 {
 					let first_byte = $len - ($len - total_read_len);
-					Ok(HighZeroBytesDroppedVarInt($meth_read(&buf[first_byte..first_byte + $len])))
+					let mut bytes = [0; $len];
+					bytes.copy_from_slice(&buf[first_byte..first_byte + $len]);
+					Ok(HighZeroBytesDroppedVarInt(<$val_type>::from_be_bytes(bytes)))
 				} else {
 					// If the encoding had extra zero bytes, return a failure even though we know
 					// what they meant (as the TLV test vectors require this)
@@ -337,13 +419,13 @@ macro_rules! impl_writeable_primitive {
 	}
 }
 
-impl_writeable_primitive!(u64, be64_to_array, 8, slice_to_be64);
-impl_writeable_primitive!(u32, be32_to_array, 4, slice_to_be32);
-impl_writeable_primitive!(u16, be16_to_array, 2, slice_to_be16);
+impl_writeable_primitive!(u64, 8);
+impl_writeable_primitive!(u32, 4);
+impl_writeable_primitive!(u16, 2);
 
 impl Writeable for u8 {
 	#[inline]
-	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 		writer.write_all(&[*self])
 	}
 }
@@ -358,7 +440,7 @@ impl Readable for u8 {
 
 impl Writeable for bool {
 	#[inline]
-	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 		writer.write_all(&[if *self {1} else {0}])
 	}
 }
@@ -380,7 +462,7 @@ macro_rules! impl_array {
 		impl Writeable for [u8; $size]
 		{
 			#[inline]
-			fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+			fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 				w.write_all(self)
 			}
 		}
@@ -403,8 +485,8 @@ impl_array!(4); // for IPv4
 impl_array!(10); // for OnionV2
 impl_array!(16); // for IPv6
 impl_array!(32); // for channel id & hmac
-impl_array!(33); // for PublicKey
-impl_array!(64); // for Signature
+impl_array!(PUBLIC_KEY_SIZE); // for PublicKey
+impl_array!(COMPACT_SIGNATURE_SIZE); // for Signature
 impl_array!(1300); // for OnionPacket.hop_data
 
 // HashMap
@@ -413,7 +495,7 @@ impl<K, V> Writeable for HashMap<K, V>
 	      V: Writeable
 {
 	#[inline]
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 	(self.len() as u16).write(w)?;
 		for (key, value) in self.iter() {
 			key.write(w)?;
@@ -441,7 +523,7 @@ impl<K, V> Readable for HashMap<K, V>
 // Vectors
 impl Writeable for Vec<u8> {
 	#[inline]
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		(self.len() as u16).write(w)?;
 		w.write_all(&self)
 	}
@@ -459,7 +541,7 @@ impl Readable for Vec<u8> {
 }
 impl Writeable for Vec<Signature> {
 	#[inline]
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		(self.len() as u16).write(w)?;
 		for e in self.iter() {
 			e.write(w)?;
@@ -473,7 +555,7 @@ impl Readable for Vec<Signature> {
 	fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 		let len: u16 = Readable::read(r)?;
 		let byte_size = (len as usize)
-		                .checked_mul(33)
+		                .checked_mul(COMPACT_SIGNATURE_SIZE)
 		                .ok_or(DecodeError::BadLengthDescriptor)?;
 		if byte_size > MAX_BUF_SIZE {
 			return Err(DecodeError::BadLengthDescriptor);
@@ -485,7 +567,7 @@ impl Readable for Vec<Signature> {
 }
 
 impl Writeable for Script {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		(self.len() as u16).write(w)?;
 		w.write_all(self.as_bytes())
 	}
@@ -501,14 +583,18 @@ impl Readable for Script {
 }
 
 impl Writeable for PublicKey {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		self.serialize().write(w)
 	}
+	#[inline]
+	fn serialized_length(&self) -> usize {
+		PUBLIC_KEY_SIZE
+	}
 }
 
 impl Readable for PublicKey {
 	fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
-		let buf: [u8; 33] = Readable::read(r)?;
+		let buf: [u8; PUBLIC_KEY_SIZE] = Readable::read(r)?;
 		match PublicKey::from_slice(&buf) {
 			Ok(key) => Ok(key),
 			Err(_) => return Err(DecodeError::InvalidValue),
@@ -517,16 +603,20 @@ impl Readable for PublicKey {
 }
 
 impl Writeable for SecretKey {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
-		let mut ser = [0; 32];
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+		let mut ser = [0; SECRET_KEY_SIZE];
 		ser.copy_from_slice(&self[..]);
 		ser.write(w)
 	}
+	#[inline]
+	fn serialized_length(&self) -> usize {
+		SECRET_KEY_SIZE
+	}
 }
 
 impl Readable for SecretKey {
 	fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
-		let buf: [u8; 32] = Readable::read(r)?;
+		let buf: [u8; SECRET_KEY_SIZE] = Readable::read(r)?;
 		match SecretKey::from_slice(&buf) {
 			Ok(key) => Ok(key),
 			Err(_) => return Err(DecodeError::InvalidValue),
@@ -535,14 +625,14 @@ impl Readable for SecretKey {
 }
 
 impl Writeable for Sha256dHash {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		w.write_all(&self[..])
 	}
 }
 
 impl Readable for Sha256dHash {
 	fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
-		use bitcoin_hashes::Hash;
+		use bitcoin::hashes::Hash;
 
 		let buf: [u8; 32] = Readable::read(r)?;
 		Ok(Sha256dHash::from_slice(&buf[..]).unwrap())
@@ -550,14 +640,18 @@ impl Readable for Sha256dHash {
 }
 
 impl Writeable for Signature {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		self.serialize_compact().write(w)
 	}
+	#[inline]
+	fn serialized_length(&self) -> usize {
+		COMPACT_SIGNATURE_SIZE
+	}
 }
 
 impl Readable for Signature {
 	fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
-		let buf: [u8; 64] = Readable::read(r)?;
+		let buf: [u8; COMPACT_SIGNATURE_SIZE] = Readable::read(r)?;
 		match Signature::from_compact(&buf) {
 			Ok(sig) => Ok(sig),
 			Err(_) => return Err(DecodeError::InvalidValue),
@@ -566,7 +660,7 @@ impl Readable for Signature {
 }
 
 impl Writeable for PaymentPreimage {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		self.0.write(w)
 	}
 }
@@ -579,7 +673,7 @@ impl Readable for PaymentPreimage {
 }
 
 impl Writeable for PaymentHash {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		self.0.write(w)
 	}
 }
@@ -592,7 +686,7 @@ impl Readable for PaymentHash {
 }
 
 impl Writeable for PaymentSecret {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		self.0.write(w)
 	}
 }
@@ -604,14 +698,24 @@ impl Readable for PaymentSecret {
 	}
 }
 
+impl<T: Writeable> Writeable for Box<T> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+		T::write(&**self, w)
+	}
+}
+
+impl<T: Readable> Readable for Box<T> {
+	fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+		Ok(Box::new(Readable::read(r)?))
+	}
+}
+
 impl<T: Writeable> Writeable for Option<T> {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		match *self {
 			None => 0u8.write(w)?,
 			Some(ref data) => {
-				let mut len_calc = LengthCalculatingWriter(0);
-				data.write(&mut len_calc).expect("No in-memory data may fail to serialize");
-				BigSize(len_calc.0 as u64 + 1).write(w)?;
+				BigSize(data.serialized_length() as u64 + 1).write(w)?;
 				data.write(w)?;
 			}
 		}
@@ -632,8 +736,38 @@ impl<T: Readable> Readable for Option<T>
 	}
 }
 
+impl Writeable for Txid {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+		w.write_all(&self[..])
+	}
+}
+
+impl Readable for Txid {
+	fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+		use bitcoin::hashes::Hash;
+
+		let buf: [u8; 32] = Readable::read(r)?;
+		Ok(Txid::from_slice(&buf[..]).unwrap())
+	}
+}
+
+impl Writeable for BlockHash {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+		w.write_all(&self[..])
+	}
+}
+
+impl Readable for BlockHash {
+	fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+		use bitcoin::hashes::Hash;
+
+		let buf: [u8; 32] = Readable::read(r)?;
+		Ok(BlockHash::from_slice(&buf[..]).unwrap())
+	}
+}
+
 impl Writeable for OutPoint {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		self.txid.write(w)?;
 		self.vout.write(w)?;
 		Ok(())
@@ -654,11 +788,10 @@ impl Readable for OutPoint {
 macro_rules! impl_consensus_ser {
 	($bitcoin_type: ty) => {
 		impl Writeable for $bitcoin_type {
-			fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+			fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 				match self.consensus_encode(WriterWriteAdaptor(writer)) {
 					Ok(_) => Ok(()),
-					Err(consensus::encode::Error::Io(e)) => Err(e),
-					Err(_) => panic!("We shouldn't get a consensus::encode::Error unless our Write generated an std::io::Error"),
+					Err(e) => Err(e),
 				}
 			}
 		}
@@ -667,8 +800,8 @@ macro_rules! impl_consensus_ser {
 			fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 				match consensus::encode::Decodable::consensus_decode(r) {
 					Ok(t) => Ok(t),
-					Err(consensus::encode::Error::Io(ref e)) if e.kind() == ::std::io::ErrorKind::UnexpectedEof => Err(DecodeError::ShortRead),
-					Err(consensus::encode::Error::Io(e)) => Err(DecodeError::Io(e)),
+					Err(consensus::encode::Error::Io(ref e)) if e.kind() == io::ErrorKind::UnexpectedEof => Err(DecodeError::ShortRead),
+					Err(consensus::encode::Error::Io(e)) => Err(DecodeError::Io(e.kind())),
 					Err(_) => Err(DecodeError::InvalidValue),
 				}
 			}
@@ -685,7 +818,7 @@ impl<T: Readable> Readable for Mutex<T> {
 	}
 }
 impl<T: Writeable> Writeable for Mutex<T> {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		self.lock().unwrap().write(w)
 	}
 }
@@ -698,8 +831,24 @@ impl<A: Readable, B: Readable> Readable for (A, B) {
 	}
 }
 impl<A: Writeable, B: Writeable> Writeable for (A, B) {
-	fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		self.0.write(w)?;
 		self.1.write(w)
 	}
 }
+
+impl<A: Readable, B: Readable, C: Readable> Readable for (A, B, C) {
+	fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+		let a: A = Readable::read(r)?;
+		let b: B = Readable::read(r)?;
+		let c: C = Readable::read(r)?;
+		Ok((a, b, c))
+	}
+}
+impl<A: Writeable, B: Writeable, C: Writeable> Writeable for (A, B, C) {
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+		self.0.write(w)?;
+		self.1.write(w)?;
+		self.2.write(w)
+	}
+}