1 use std::result::Result;
2 use std::io::{Read, Write};
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 struct that holds an std::io::Write-impl'ing object and implements various
19 /// rust-lightning-specific write functions.
20 pub struct Writer<W: Write> { writer: W }
21 /// A struct that holds an std::io::Read-impl'ing object and implements various
22 /// rust-lightning-specific read functions.
23 pub struct Reader<R: Read> { reader: R }
25 /// A trait that various rust-lightning types implement allowing them to be written out to a Writer
26 pub trait Writeable<W: Write> {
27 /// Writes self out to the given Writer
28 fn write(&self, writer: &mut Writer<W>) -> Result<(), DecodeError>;
31 /// A trait that various rust-lightning types implement allowing them to be read in from a Reader
36 /// Reads a Self in from the given Reader
37 fn read(reader: &mut Reader<R>) -> Result<Self, DecodeError>;
40 impl<W: Write> Writer<W> {
41 /// Creates a new Writer from an std::io::Write-impl'ing object
42 pub fn new(writer: W) -> Writer<W> {
43 return Writer { writer }
45 /// Consumes this object and returns the original writer
46 pub fn into_inner(self) -> W { self.writer }
47 /// Gets a reference to the original writer
48 pub fn get_ref(&self) -> &W { &self.writer }
49 fn write_u64(&mut self, v: u64) -> Result<(), DecodeError> {
50 Ok(self.writer.write_all(&be64_to_array(v))?)
52 fn write_u32(&mut self, v: u32) -> Result<(), DecodeError> {
53 Ok(self.writer.write_all(&be32_to_array(v))?)
55 fn write_u16(&mut self, v: u16) -> Result<(), DecodeError> {
56 Ok(self.writer.write_all(&be16_to_array(v))?)
58 fn write_u8(&mut self, v: u8) -> Result<(), DecodeError> {
59 Ok(self.writer.write_all(&[v])?)
61 fn write_bool(&mut self, v: bool) -> Result<(), DecodeError> {
62 Ok(self.writer.write_all(&[if v {1} else {0}])?)
64 pub(crate) fn write_all(&mut self, v: &[u8]) -> Result<(), DecodeError> {
65 Ok(self.writer.write_all(v)?)
69 impl<R: Read> Reader<R> {
70 /// Creates a new Reader from an std::io::Read-impl'ing object
71 pub fn new(reader: R) -> Reader<R> {
72 return Reader { reader }
74 /// Consumes this object and returns the original reader
75 pub fn into_inner(self) -> R { self.reader }
76 /// Gets a reference to the original reader
77 pub fn get_ref(&self) -> &R { &self.reader }
79 fn read_u64(&mut self) -> Result<u64, DecodeError> {
81 self.reader.read_exact(&mut buf)?;
82 Ok(slice_to_be64(&buf))
85 fn read_u32(&mut self) -> Result<u32, DecodeError> {
87 self.reader.read_exact(&mut buf)?;
88 Ok(slice_to_be32(&buf))
91 fn read_u16(&mut self) -> Result<u16, DecodeError> {
93 self.reader.read_exact(&mut buf)?;
94 Ok(slice_to_be16(&buf))
97 fn read_u8(&mut self) -> Result<u8, DecodeError> {
99 self.reader.read_exact(&mut buf)?;
102 fn read_bool(&mut self) -> Result<bool, DecodeError> {
103 let mut buf = [0; 1];
104 self.reader.read_exact(&mut buf)?;
105 if buf[0] != 0 && buf[0] != 1 {
106 return Err(DecodeError::InvalidValue);
110 pub(crate) fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), DecodeError> {
111 Ok(self.reader.read_exact(buf)?)
113 pub(crate) fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, DecodeError> {
114 Ok(self.reader.read_to_end(buf)?)
118 macro_rules! impl_writeable_primitive {
119 ($val_type:ty, $meth_write:ident, $meth_read:ident) => {
120 impl<W:Write> Writeable<W> for $val_type {
122 fn write(&self, writer: &mut Writer<W>) -> Result<(), DecodeError> {
123 writer.$meth_write(*self)
126 impl<R:Read> Readable<R> for $val_type {
128 fn read(reader: &mut Reader<R>) -> Result<$val_type, DecodeError> {
135 impl_writeable_primitive!(u64, write_u64, read_u64);
136 impl_writeable_primitive!(u32, write_u32, read_u32);
137 impl_writeable_primitive!(u16, write_u16, read_u16);
138 impl_writeable_primitive!(u8, write_u8, read_u8);
139 impl_writeable_primitive!(bool, write_bool, read_bool);
142 macro_rules! impl_array {
144 impl<W> Writeable<W> for [u8; $size]
148 fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
154 impl<R> Readable<R> for [u8; $size]
158 fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
159 let mut buf = [0u8; $size];
160 r.read_exact(&mut buf)?;
167 //TODO: performance issue with [u8; size] with impl_array!()
168 impl_array!(32); // for channel id & hmac
169 impl_array!(33); // for PublicKey
170 impl_array!(64); // for Signature
171 impl_array!(1300); // for OnionPacket.hop_data
174 impl<W, K, V> Writeable<W> for HashMap<K, V>
176 K: Writeable<W> + Eq + Hash,
180 fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
181 (self.len() as u16).write(w)?;
182 for (key, value) in self.iter() {
190 impl<R, K, V> Readable<R> for HashMap<K, V>
192 K: Readable<R> + Eq + Hash,
196 fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
197 let len: u16 = Readable::read(r)?;
198 let mut ret = HashMap::with_capacity(len as usize);
200 ret.insert(K::read(r)?, V::read(r)?);
207 impl<W: Write, T: Writeable<W>> Writeable<W> for Vec<T> {
209 fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
210 let byte_size = (self.len() as usize)
211 .checked_mul(mem::size_of::<T>())
212 .ok_or(DecodeError::BadLengthDescriptor)?;
213 if byte_size > MAX_BUF_SIZE {
214 return Err(DecodeError::BadLengthDescriptor);
216 (self.len() as u16).write(w)?;
217 // performance with Vec<u8>
218 for e in self.iter() {
225 impl<R: Read, T: Readable<R>> Readable<R> for Vec<T> {
227 fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
228 let len: u16 = Readable::read(r)?;
229 let byte_size = (len as usize)
230 .checked_mul(mem::size_of::<T>())
231 .ok_or(DecodeError::BadLengthDescriptor)?;
232 if byte_size > MAX_BUF_SIZE {
233 return Err(DecodeError::BadLengthDescriptor);
235 let mut ret = Vec::with_capacity(len as usize);
236 for _ in 0..len { ret.push(T::read(r)?); }
241 impl<W: Write> Writeable<W> for Script {
242 fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
243 self.to_bytes().to_vec().write(w)
247 impl<R: Read> Readable<R> for Script {
248 fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
249 let len = <u16 as Readable<R>>::read(r)? as usize;
250 let mut buf = vec![0; len];
251 r.read_exact(&mut buf)?;
252 Ok(Script::from(buf))
256 impl<W: Write> Writeable<W> for Option<Script> {
257 fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
258 if let &Some(ref script) = self {
265 impl<R: Read> Readable<R> for Option<Script> {
266 fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
267 match <u16 as Readable<R>>::read(r) {
269 let mut buf = vec![0; len as usize];
270 r.read_exact(&mut buf)?;
271 Ok(Some(Script::from(buf)))
273 Err(DecodeError::ShortRead) => Ok(None),
279 impl<W: Write> Writeable<W> for PublicKey {
280 fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
281 self.serialize().write(w)
285 impl<R: Read> Readable<R> for PublicKey {
286 fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
287 let buf: [u8; 33] = Readable::read(r)?;
288 match PublicKey::from_slice(&Secp256k1::without_caps(), &buf) {
290 Err(_) => return Err(DecodeError::BadPublicKey),
295 impl<W: Write> Writeable<W> for Sha256dHash {
296 fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
297 self.as_bytes().write(w)
301 impl<R: Read> Readable<R> for Sha256dHash {
302 fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
303 let buf: [u8; 32] = Readable::read(r)?;
304 Ok(From::from(&buf[..]))
308 impl<W: Write> Writeable<W> for Signature {
309 fn write(&self, w: &mut Writer<W>) -> Result<(), DecodeError> {
310 self.serialize_compact(&Secp256k1::without_caps()).write(w)
314 impl<R: Read> Readable<R> for Signature {
315 fn read(r: &mut Reader<R>) -> Result<Self, DecodeError> {
316 let buf: [u8; 64] = Readable::read(r)?;
317 match Signature::from_compact(&Secp256k1::without_caps(), &buf) {
319 Err(_) => return Err(DecodeError::BadSignature),