1 use std::result::Result;
3 use std::collections::HashMap;
6 use secp256k1::{Secp256k1, Signature};
7 use secp256k1::key::PublicKey;
8 use bitcoin::util::hash::Sha256dHash;
9 use bitcoin::blockdata::script::Script;
10 use std::marker::Sized;
11 use ln::msgs::DecodeError;
13 use util::byte_utils::{be64_to_array, be32_to_array, be16_to_array, slice_to_be16, slice_to_be32, slice_to_be64};
15 const MAX_BUF_SIZE: usize = 64 * 1024;
17 /// A trait that is similar to std::io::Write but has one extra function which can be used to size
18 /// buffers being written into.
19 /// An impl is provided for any type that also impls std::io::Write which simply ignores size
22 /// Writes the given buf out. See std::io::Write::write_all for more
23 fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error>;
24 /// Hints that data of the given size is about the be written. This may not always be called
25 /// prior to data being written and may be safely ignored.
26 fn size_hint(&mut self, size: usize);
29 impl<W: ::std::io::Write> Writer for W {
31 fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error> {
32 <Self as ::std::io::Write>::write_all(self, buf)
35 fn size_hint(&mut self, _size: usize) { }
38 /// A trait that various rust-lightning types implement allowing them to be written out to a Writer
39 pub trait Writeable<W: Writer> {
40 /// Writes self out to the given Writer
41 fn write(&self, writer: &mut W) -> Result<(), DecodeError>;
44 /// A trait that various rust-lightning types implement allowing them to be read in from a Read
49 /// Reads a Self in from the given Read
50 fn read(reader: &mut R) -> Result<Self, DecodeError>;
53 macro_rules! impl_writeable_primitive {
54 ($val_type:ty, $meth_write:ident, $len: expr, $meth_read:ident) => {
55 impl<W: Writer> Writeable<W> for $val_type {
57 fn write(&self, writer: &mut W) -> Result<(), DecodeError> {
58 Ok(writer.write_all(&$meth_write(*self))?)
61 impl<R: Read> Readable<R> for $val_type {
63 fn read(reader: &mut R) -> Result<$val_type, DecodeError> {
64 let mut buf = [0; $len];
65 reader.read_exact(&mut buf)?;
72 impl_writeable_primitive!(u64, be64_to_array, 8, slice_to_be64);
73 impl_writeable_primitive!(u32, be32_to_array, 4, slice_to_be32);
74 impl_writeable_primitive!(u16, be16_to_array, 2, slice_to_be16);
76 impl<W: Writer> Writeable<W> for u8 {
78 fn write(&self, writer: &mut W) -> Result<(), DecodeError> {
79 Ok(writer.write_all(&[*self])?)
82 impl<R: Read> Readable<R> for u8 {
84 fn read(reader: &mut R) -> Result<u8, DecodeError> {
86 reader.read_exact(&mut buf)?;
91 impl<W: Writer> Writeable<W> for bool {
93 fn write(&self, writer: &mut W) -> Result<(), DecodeError> {
94 Ok(writer.write_all(&[if *self {1} else {0}])?)
97 impl<R: Read> Readable<R> for bool {
99 fn read(reader: &mut R) -> Result<bool, DecodeError> {
100 let mut buf = [0; 1];
101 reader.read_exact(&mut buf)?;
102 if buf[0] != 0 && buf[0] != 1 {
103 return Err(DecodeError::InvalidValue);
110 macro_rules! impl_array {
112 impl<W: Writer> Writeable<W> for [u8; $size]
115 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
121 impl<R: Read> Readable<R> for [u8; $size]
124 fn read(r: &mut R) -> Result<Self, DecodeError> {
125 let mut buf = [0u8; $size];
126 r.read_exact(&mut buf)?;
133 //TODO: performance issue with [u8; size] with impl_array!()
134 impl_array!(32); // for channel id & hmac
135 impl_array!(33); // for PublicKey
136 impl_array!(64); // for Signature
137 impl_array!(1300); // for OnionPacket.hop_data
140 impl<W, K, V> Writeable<W> for HashMap<K, V>
142 K: Writeable<W> + Eq + Hash,
146 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
147 (self.len() as u16).write(w)?;
148 for (key, value) in self.iter() {
156 impl<R, K, V> Readable<R> for HashMap<K, V>
158 K: Readable<R> + Eq + Hash,
162 fn read(r: &mut R) -> Result<Self, DecodeError> {
163 let len: u16 = Readable::read(r)?;
164 let mut ret = HashMap::with_capacity(len as usize);
166 ret.insert(K::read(r)?, V::read(r)?);
173 impl<W: Writer> Writeable<W> for Vec<u8> {
175 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
176 (self.len() as u16).write(w)?;
177 Ok(w.write_all(&self)?)
181 impl<R: Read> Readable<R> for Vec<u8> {
183 fn read(r: &mut R) -> Result<Self, DecodeError> {
184 let len: u16 = Readable::read(r)?;
185 let mut ret = Vec::with_capacity(len as usize);
186 ret.resize(len as usize, 0);
187 r.read_exact(&mut ret)?;
191 impl<W: Writer> Writeable<W> for Vec<Signature> {
193 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
194 let byte_size = (self.len() as usize)
196 .ok_or(DecodeError::BadLengthDescriptor)?;
197 if byte_size > MAX_BUF_SIZE {
198 return Err(DecodeError::BadLengthDescriptor);
200 (self.len() as u16).write(w)?;
201 for e in self.iter() {
208 impl<R: Read> Readable<R> for Vec<Signature> {
210 fn read(r: &mut R) -> Result<Self, DecodeError> {
211 let len: u16 = Readable::read(r)?;
212 let byte_size = (len as usize)
214 .ok_or(DecodeError::BadLengthDescriptor)?;
215 if byte_size > MAX_BUF_SIZE {
216 return Err(DecodeError::BadLengthDescriptor);
218 let mut ret = Vec::with_capacity(len as usize);
219 for _ in 0..len { ret.push(Signature::read(r)?); }
224 impl<W: Writer> Writeable<W> for Script {
225 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
226 (self.len() as u16).write(w)?;
227 Ok(w.write_all(self.as_bytes())?)
231 impl<R: Read> Readable<R> for Script {
232 fn read(r: &mut R) -> Result<Self, DecodeError> {
233 let len = <u16 as Readable<R>>::read(r)? as usize;
234 let mut buf = vec![0; len];
235 r.read_exact(&mut buf)?;
236 Ok(Script::from(buf))
240 impl<W: Writer> Writeable<W> for Option<Script> {
241 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
242 if let &Some(ref script) = self {
249 impl<R: Read> Readable<R> for Option<Script> {
250 fn read(r: &mut R) -> Result<Self, DecodeError> {
251 match <u16 as Readable<R>>::read(r) {
253 let mut buf = vec![0; len as usize];
254 r.read_exact(&mut buf)?;
255 Ok(Some(Script::from(buf)))
257 Err(DecodeError::ShortRead) => Ok(None),
263 impl<W: Writer> Writeable<W> for PublicKey {
264 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
265 self.serialize().write(w)
269 impl<R: Read> Readable<R> for PublicKey {
270 fn read(r: &mut R) -> Result<Self, DecodeError> {
271 let buf: [u8; 33] = Readable::read(r)?;
272 match PublicKey::from_slice(&Secp256k1::without_caps(), &buf) {
274 Err(_) => return Err(DecodeError::BadPublicKey),
279 impl<W: Writer> Writeable<W> for Sha256dHash {
280 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
281 self.as_bytes().write(w)
285 impl<R: Read> Readable<R> for Sha256dHash {
286 fn read(r: &mut R) -> Result<Self, DecodeError> {
287 let buf: [u8; 32] = Readable::read(r)?;
288 Ok(From::from(&buf[..]))
292 impl<W: Writer> Writeable<W> for Signature {
293 fn write(&self, w: &mut W) -> Result<(), DecodeError> {
294 self.serialize_compact(&Secp256k1::without_caps()).write(w)
298 impl<R: Read> Readable<R> for Signature {
299 fn read(r: &mut R) -> Result<Self, DecodeError> {
300 let buf: [u8; 64] = Readable::read(r)?;
301 match Signature::from_compact(&Secp256k1::without_caps(), &buf) {
303 Err(_) => return Err(DecodeError::BadSignature),