1 use std::result::Result;
3 use std::collections::HashMap;
7 use secp256k1::{Secp256k1, Signature};
8 use secp256k1::key::PublicKey;
9 use bitcoin::util::hash::Sha256dHash;
10 use bitcoin::blockdata::script::Script;
11 use std::marker::Sized;
12 use ln::msgs::DecodeError;
14 use util::byte_utils::{be64_to_array, be32_to_array, be16_to_array, slice_to_be16, slice_to_be32, slice_to_be64};
16 const MAX_BUF_SIZE: usize = 64 * 1024;
18 /// A trait that is similar to std::io::Write.
19 /// An impl is provided for any type that also impls std::io::Write.
21 /// Writes the given buf out. See std::io::Write::write_all for more
22 fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error>;
25 impl<W: ::std::io::Write> Writer for W {
26 fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error> {
27 <Self as ::std::io::Write>::write_all(self, buf)
31 /// A trait that various rust-lightning types implement allowing them to be written out to a Writer
32 pub trait Writeable<W: Writer> {
33 /// Writes self out to the given Writer
34 fn write(&self, writer: &mut W) -> Result<(), DecodeError>;
37 /// A trait that various rust-lightning types implement allowing them to be read in from a Read
42 /// Reads a Self in from the given Read
43 fn read(reader: &mut R) -> Result<Self, DecodeError>;
46 macro_rules! impl_writeable_primitive {
47 ($val_type:ty, $meth_write:ident, $len: expr, $meth_read:ident) => {
48 impl<W: Writer> Writeable<W> for $val_type {
50 fn write(&self, writer: &mut W) -> Result<(), DecodeError> {
51 Ok(writer.write_all(&$meth_write(*self))?)
54 impl<R: Read> Readable<R> for $val_type {
56 fn read(reader: &mut R) -> Result<$val_type, DecodeError> {
57 let mut buf = [0; $len];
58 reader.read_exact(&mut buf)?;
65 impl_writeable_primitive!(u64, be64_to_array, 8, slice_to_be64);
66 impl_writeable_primitive!(u32, be32_to_array, 4, slice_to_be32);
67 impl_writeable_primitive!(u16, be16_to_array, 2, slice_to_be16);
69 impl<W: Writer> Writeable<W> for u8 {
71 fn write(&self, writer: &mut W) -> Result<(), DecodeError> {
72 Ok(writer.write_all(&[*self])?)
75 impl<R: Read> Readable<R> for u8 {
77 fn read(reader: &mut R) -> Result<u8, DecodeError> {
79 reader.read_exact(&mut buf)?;
84 impl<W: Writer> Writeable<W> for bool {
86 fn write(&self, writer: &mut W) -> Result<(), DecodeError> {
87 Ok(writer.write_all(&[if *self {1} else {0}])?)
90 impl<R: Read> Readable<R> for bool {
92 fn read(reader: &mut R) -> Result<bool, DecodeError> {
94 reader.read_exact(&mut buf)?;
95 if buf[0] != 0 && buf[0] != 1 {
96 return Err(DecodeError::InvalidValue);
103 macro_rules! impl_array {
105 impl<W: Writer> Writeable<W> for [u8; $size]
108 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
114 impl<R: Read> Readable<R> for [u8; $size]
117 fn read(r: &mut R) -> Result<Self, DecodeError> {
118 let mut buf = [0u8; $size];
119 r.read_exact(&mut buf)?;
126 //TODO: performance issue with [u8; size] with impl_array!()
127 impl_array!(32); // for channel id & hmac
128 impl_array!(33); // for PublicKey
129 impl_array!(64); // for Signature
130 impl_array!(1300); // for OnionPacket.hop_data
133 impl<W, K, V> Writeable<W> for HashMap<K, V>
135 K: Writeable<W> + Eq + Hash,
139 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
140 (self.len() as u16).write(w)?;
141 for (key, value) in self.iter() {
149 impl<R, K, V> Readable<R> for HashMap<K, V>
151 K: Readable<R> + Eq + Hash,
155 fn read(r: &mut R) -> Result<Self, DecodeError> {
156 let len: u16 = Readable::read(r)?;
157 let mut ret = HashMap::with_capacity(len as usize);
159 ret.insert(K::read(r)?, V::read(r)?);
166 impl<W: Writer, T: Writeable<W>> Writeable<W> for Vec<T> {
168 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
169 let byte_size = (self.len() as usize)
170 .checked_mul(mem::size_of::<T>())
171 .ok_or(DecodeError::BadLengthDescriptor)?;
172 if byte_size > MAX_BUF_SIZE {
173 return Err(DecodeError::BadLengthDescriptor);
175 (self.len() as u16).write(w)?;
176 // performance with Vec<u8>
177 for e in self.iter() {
184 impl<R: Read, T: Readable<R>> Readable<R> for Vec<T> {
186 fn read(r: &mut R) -> Result<Self, DecodeError> {
187 let len: u16 = Readable::read(r)?;
188 let byte_size = (len as usize)
189 .checked_mul(mem::size_of::<T>())
190 .ok_or(DecodeError::BadLengthDescriptor)?;
191 if byte_size > MAX_BUF_SIZE {
192 return Err(DecodeError::BadLengthDescriptor);
194 let mut ret = Vec::with_capacity(len as usize);
195 for _ in 0..len { ret.push(T::read(r)?); }
200 impl<W: Writer> Writeable<W> for Script {
201 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
202 self.to_bytes().to_vec().write(w)
206 impl<R: Read> Readable<R> for Script {
207 fn read(r: &mut R) -> Result<Self, DecodeError> {
208 let len = <u16 as Readable<R>>::read(r)? as usize;
209 let mut buf = vec![0; len];
210 r.read_exact(&mut buf)?;
211 Ok(Script::from(buf))
215 impl<W: Writer> Writeable<W> for Option<Script> {
216 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
217 if let &Some(ref script) = self {
224 impl<R: Read> Readable<R> for Option<Script> {
225 fn read(r: &mut R) -> Result<Self, DecodeError> {
226 match <u16 as Readable<R>>::read(r) {
228 let mut buf = vec![0; len as usize];
229 r.read_exact(&mut buf)?;
230 Ok(Some(Script::from(buf)))
232 Err(DecodeError::ShortRead) => Ok(None),
238 impl<W: Writer> Writeable<W> for PublicKey {
239 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
240 self.serialize().write(w)
244 impl<R: Read> Readable<R> for PublicKey {
245 fn read(r: &mut R) -> Result<Self, DecodeError> {
246 let buf: [u8; 33] = Readable::read(r)?;
247 match PublicKey::from_slice(&Secp256k1::without_caps(), &buf) {
249 Err(_) => return Err(DecodeError::BadPublicKey),
254 impl<W: Writer> Writeable<W> for Sha256dHash {
255 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
256 self.as_bytes().write(w)
260 impl<R: Read> Readable<R> for Sha256dHash {
261 fn read(r: &mut R) -> Result<Self, DecodeError> {
262 let buf: [u8; 32] = Readable::read(r)?;
263 Ok(From::from(&buf[..]))
267 impl<W: Writer> Writeable<W> for Signature {
268 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
269 self.serialize_compact(&Secp256k1::without_caps()).write(w)
273 impl<R: Read> Readable<R> for Signature {
274 fn read(r: &mut R) -> Result<Self, DecodeError> {
275 let buf: [u8; 64] = Readable::read(r)?;
276 match Signature::from_compact(&Secp256k1::without_caps(), &buf) {
278 Err(_) => return Err(DecodeError::BadSignature),