_ Git - rust-lightning/blob - lightning/src/util/ser.rs

   1 // This file is Copyright its original authors, visible in version control
   2 // history.
   3 //
   4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
   5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
   7 // You may not use this file except in accordance with one or both of these
   8 // licenses.
   9
  10 //! A very simple serialization framework which is used to serialize/deserialize messages as well
  11 //! as ChannelsManagers and ChannelMonitors.
  12
  13 use crate::prelude::*;
  14 use crate::io::{self, Read, Write};
  15 use crate::io_extras::{copy, sink};
  16 use core::hash::Hash;
  17 use crate::sync::Mutex;
  18 use core::cmp;
  19 use core::convert::TryFrom;
  20 use core::ops::Deref;
  21
  22 use bitcoin::secp256k1::{PublicKey, SecretKey};
  23 use bitcoin::secp256k1::constants::{PUBLIC_KEY_SIZE, SECRET_KEY_SIZE, COMPACT_SIGNATURE_SIZE};
  24 use bitcoin::secp256k1::ecdsa::Signature;
  25 use bitcoin::blockdata::script::Script;
  26 use bitcoin::blockdata::transaction::{OutPoint, Transaction, TxOut};
  27 use bitcoin::consensus;
  28 use bitcoin::consensus::Encodable;
  29 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
  30 use bitcoin::hash_types::{Txid, BlockHash};
  31 use core::marker::Sized;
  32 use core::time::Duration;
  33 use crate::ln::msgs::DecodeError;
  34 use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
  35
  36 use crate::util::byte_utils::{be48_to_array, slice_to_be48};
  37
  38 /// serialization buffer size
  39 pub const MAX_BUF_SIZE: usize = 64 * 1024;
  40
  41 /// A simplified version of std::io::Write that exists largely for backwards compatibility.
  42 /// An impl is provided for any type that also impls std::io::Write.
  43 ///
  44 /// (C-not exported) as we only export serialization to/from byte arrays instead
  45 pub trait Writer {
  46         /// Writes the given buf out. See std::io::Write::write_all for more
  47         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error>;
  48 }
  49
  50 impl<W: Write> Writer for W {
  51         #[inline]
  52         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  53                 <Self as io::Write>::write_all(self, buf)
  54         }
  55 }
  56
  57 pub(crate) struct WriterWriteAdaptor<'a, W: Writer + 'a>(pub &'a mut W);
  58 impl<'a, W: Writer + 'a> Write for WriterWriteAdaptor<'a, W> {
  59         #[inline]
  60         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  61                 self.0.write_all(buf)
  62         }
  63         #[inline]
  64         fn write(&mut self, buf: &[u8]) -> Result<usize, io::Error> {
  65                 self.0.write_all(buf)?;
  66                 Ok(buf.len())
  67         }
  68         #[inline]
  69         fn flush(&mut self) -> Result<(), io::Error> {
  70                 Ok(())
  71         }
  72 }
  73
  74 pub(crate) struct VecWriter(pub Vec<u8>);
  75 impl Writer for VecWriter {
  76         #[inline]
  77         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  78                 self.0.extend_from_slice(buf);
  79                 Ok(())
  80         }
  81 }
  82
  83 /// Writer that only tracks the amount of data written - useful if you need to calculate the length
  84 /// of some data when serialized but don't yet need the full data.
  85 pub(crate) struct LengthCalculatingWriter(pub usize);
  86 impl Writer for LengthCalculatingWriter {
  87         #[inline]
  88         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  89                 self.0 += buf.len();
  90                 Ok(())
  91         }
  92 }
  93
  94 /// Essentially std::io::Take but a bit simpler and with a method to walk the underlying stream
  95 /// forward to ensure we always consume exactly the fixed length specified.
  96 pub(crate) struct FixedLengthReader<R: Read> {
  97         read: R,
  98         bytes_read: u64,
  99         total_bytes: u64,
 100 }
 101 impl<R: Read> FixedLengthReader<R> {
 102         pub fn new(read: R, total_bytes: u64) -> Self {
 103                 Self { read, bytes_read: 0, total_bytes }
 104         }
 105
 106         #[inline]
 107         pub fn bytes_remain(&mut self) -> bool {
 108                 self.bytes_read != self.total_bytes
 109         }
 110
 111         #[inline]
 112         pub fn eat_remaining(&mut self) -> Result<(), DecodeError> {
 113                 copy(self, &mut sink()).unwrap();
 114                 if self.bytes_read != self.total_bytes {
 115                         Err(DecodeError::ShortRead)
 116                 } else {
 117                         Ok(())
 118                 }
 119         }
 120 }
 121 impl<R: Read> Read for FixedLengthReader<R> {
 122         #[inline]
 123         fn read(&mut self, dest: &mut [u8]) -> Result<usize, io::Error> {
 124                 if self.total_bytes == self.bytes_read {
 125                         Ok(0)
 126                 } else {
 127                         let read_len = cmp::min(dest.len() as u64, self.total_bytes - self.bytes_read);
 128                         match self.read.read(&mut dest[0..(read_len as usize)]) {
 129                                 Ok(v) => {
 130                                         self.bytes_read += v as u64;
 131                                         Ok(v)
 132                                 },
 133                                 Err(e) => Err(e),
 134                         }
 135                 }
 136         }
 137 }
 138
 139 impl<R: Read> LengthRead for FixedLengthReader<R> {
 140         #[inline]
 141         fn total_bytes(&self) -> u64 {
 142                 self.total_bytes
 143         }
 144 }
 145
 146 /// A Read which tracks whether any bytes have been read at all. This allows us to distinguish
 147 /// between "EOF reached before we started" and "EOF reached mid-read".
 148 pub(crate) struct ReadTrackingReader<R: Read> {
 149         read: R,
 150         pub have_read: bool,
 151 }
 152 impl<R: Read> ReadTrackingReader<R> {
 153         pub fn new(read: R) -> Self {
 154                 Self { read, have_read: false }
 155         }
 156 }
 157 impl<R: Read> Read for ReadTrackingReader<R> {
 158         #[inline]
 159         fn read(&mut self, dest: &mut [u8]) -> Result<usize, io::Error> {
 160                 match self.read.read(dest) {
 161                         Ok(0) => Ok(0),
 162                         Ok(len) => {
 163                                 self.have_read = true;
 164                                 Ok(len)
 165                         },
 166                         Err(e) => Err(e),
 167                 }
 168         }
 169 }
 170
 171 /// A trait that various rust-lightning types implement allowing them to be written out to a Writer
 172 ///
 173 /// (C-not exported) as we only export serialization to/from byte arrays instead
 174 pub trait Writeable {
 175         /// Writes self out to the given Writer
 176         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error>;
 177
 178         /// Writes self out to a Vec<u8>
 179         fn encode(&self) -> Vec<u8> {
 180                 let mut msg = VecWriter(Vec::new());
 181                 self.write(&mut msg).unwrap();
 182                 msg.0
 183         }
 184
 185         /// Writes self out to a Vec<u8>
 186         #[cfg(test)]
 187         fn encode_with_len(&self) -> Vec<u8> {
 188                 let mut msg = VecWriter(Vec::new());
 189                 0u16.write(&mut msg).unwrap();
 190                 self.write(&mut msg).unwrap();
 191                 let len = msg.0.len();
 192                 msg.0[..2].copy_from_slice(&(len as u16 - 2).to_be_bytes());
 193                 msg.0
 194         }
 195
 196         /// Gets the length of this object after it has been serialized. This can be overridden to
 197         /// optimize cases where we prepend an object with its length.
 198         // Note that LLVM optimizes this away in most cases! Check that it isn't before you override!
 199         #[inline]
 200         fn serialized_length(&self) -> usize {
 201                 let mut len_calc = LengthCalculatingWriter(0);
 202                 self.write(&mut len_calc).expect("No in-memory data may fail to serialize");
 203                 len_calc.0
 204         }
 205 }
 206
 207 impl<'a, T: Writeable> Writeable for &'a T {
 208         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { (*self).write(writer) }
 209 }
 210
 211 /// A trait that various rust-lightning types implement allowing them to be read in from a Read
 212 ///
 213 /// (C-not exported) as we only export serialization to/from byte arrays instead
 214 pub trait Readable
 215         where Self: Sized
 216 {
 217         /// Reads a Self in from the given Read
 218         fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError>;
 219 }
 220
 221 /// A trait that various higher-level rust-lightning types implement allowing them to be read in
 222 /// from a Read given some additional set of arguments which is required to deserialize.
 223 ///
 224 /// (C-not exported) as we only export serialization to/from byte arrays instead
 225 pub trait ReadableArgs<P>
 226         where Self: Sized
 227 {
 228         /// Reads a Self in from the given Read
 229         fn read<R: Read>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 230 }
 231
 232 /// A std::io::Read that also provides the total bytes available to read.
 233 pub(crate) trait LengthRead: Read {
 234         /// The total number of bytes available to read.
 235         fn total_bytes(&self) -> u64;
 236 }
 237
 238 /// A trait that various higher-level rust-lightning types implement allowing them to be read in
 239 /// from a Read given some additional set of arguments which is required to deserialize, requiring
 240 /// the implementer to provide the total length of the read.
 241 pub(crate) trait LengthReadableArgs<P> where Self: Sized
 242 {
 243         /// Reads a Self in from the given LengthRead
 244         fn read<R: LengthRead>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 245 }
 246
 247 /// A trait that various higher-level rust-lightning types implement allowing them to be read in
 248 /// from a Read, requiring the implementer to provide the total length of the read.
 249 pub(crate) trait LengthReadable where Self: Sized
 250 {
 251         /// Reads a Self in from the given LengthRead
 252         fn read<R: LengthRead>(reader: &mut R) -> Result<Self, DecodeError>;
 253 }
 254
 255 /// A trait that various rust-lightning types implement allowing them to (maybe) be read in from a Read
 256 ///
 257 /// (C-not exported) as we only export serialization to/from byte arrays instead
 258 pub trait MaybeReadable
 259         where Self: Sized
 260 {
 261         /// Reads a Self in from the given Read
 262         fn read<R: Read>(reader: &mut R) -> Result<Option<Self>, DecodeError>;
 263 }
 264
 265 impl<T: Readable> MaybeReadable for T {
 266         #[inline]
 267         fn read<R: Read>(reader: &mut R) -> Result<Option<T>, DecodeError> {
 268                 Ok(Some(Readable::read(reader)?))
 269         }
 270 }
 271
 272 pub(crate) struct OptionDeserWrapper<T: Readable>(pub Option<T>);
 273 impl<T: Readable> Readable for OptionDeserWrapper<T> {
 274         #[inline]
 275         fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
 276                 Ok(Self(Some(Readable::read(reader)?)))
 277         }
 278 }
 279 /// When handling default_values, we want to map the default-value T directly
 280 /// to a OptionDeserWrapper<T> in a way that works for `field: T = t;` as
 281 /// well. Thus, we assume `Into<T> for T` does nothing and use that.
 282 impl<T: Readable> From<T> for OptionDeserWrapper<T> {
 283         fn from(t: T) -> OptionDeserWrapper<T> { OptionDeserWrapper(Some(t)) }
 284 }
 285
 286 pub(crate) struct U48(pub u64);
 287 impl Writeable for U48 {
 288         #[inline]
 289         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 290                 writer.write_all(&be48_to_array(self.0))
 291         }
 292 }
 293 impl Readable for U48 {
 294         #[inline]
 295         fn read<R: Read>(reader: &mut R) -> Result<U48, DecodeError> {
 296                 let mut buf = [0; 6];
 297                 reader.read_exact(&mut buf)?;
 298                 Ok(U48(slice_to_be48(&buf)))
 299         }
 300 }
 301
 302 /// Lightning TLV uses a custom variable-length integer called BigSize. It is similar to Bitcoin's
 303 /// variable-length integers except that it is serialized in big-endian instead of little-endian.
 304 ///
 305 /// Like Bitcoin's variable-length integer, it exhibits ambiguity in that certain values can be
 306 /// encoded in several different ways, which we must check for at deserialization-time. Thus, if
 307 /// you're looking for an example of a variable-length integer to use for your own project, move
 308 /// along, this is a rather poor design.
 309 pub struct BigSize(pub u64);
 310 impl Writeable for BigSize {
 311         #[inline]
 312         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 313                 match self.0 {
 314                         0...0xFC => {
 315                                 (self.0 as u8).write(writer)
 316                         },
 317                         0xFD...0xFFFF => {
 318                                 0xFDu8.write(writer)?;
 319                                 (self.0 as u16).write(writer)
 320                         },
 321                         0x10000...0xFFFFFFFF => {
 322                                 0xFEu8.write(writer)?;
 323                                 (self.0 as u32).write(writer)
 324                         },
 325                         _ => {
 326                                 0xFFu8.write(writer)?;
 327                                 (self.0 as u64).write(writer)
 328                         },
 329                 }
 330         }
 331 }
 332 impl Readable for BigSize {
 333         #[inline]
 334         fn read<R: Read>(reader: &mut R) -> Result<BigSize, DecodeError> {
 335                 let n: u8 = Readable::read(reader)?;
 336                 match n {
 337                         0xFF => {
 338                                 let x: u64 = Readable::read(reader)?;
 339                                 if x < 0x100000000 {
 340                                         Err(DecodeError::InvalidValue)
 341                                 } else {
 342                                         Ok(BigSize(x))
 343                                 }
 344                         }
 345                         0xFE => {
 346                                 let x: u32 = Readable::read(reader)?;
 347                                 if x < 0x10000 {
 348                                         Err(DecodeError::InvalidValue)
 349                                 } else {
 350                                         Ok(BigSize(x as u64))
 351                                 }
 352                         }
 353                         0xFD => {
 354                                 let x: u16 = Readable::read(reader)?;
 355                                 if x < 0xFD {
 356                                         Err(DecodeError::InvalidValue)
 357                                 } else {
 358                                         Ok(BigSize(x as u64))
 359                                 }
 360                         }
 361                         n => Ok(BigSize(n as u64))
 362                 }
 363         }
 364 }
 365
 366 /// In TLV we occasionally send fields which only consist of, or potentially end with, a
 367 /// variable-length integer which is simply truncated by skipping high zero bytes. This type
 368 /// encapsulates such integers implementing Readable/Writeable for them.
 369 #[cfg_attr(test, derive(PartialEq, Eq))]
 370 #[derive(Clone, Debug)]
 371 pub(crate) struct HighZeroBytesDroppedBigSize<T>(pub T);
 372
 373 macro_rules! impl_writeable_primitive {
 374         ($val_type:ty, $len: expr) => {
 375                 impl Writeable for $val_type {
 376                         #[inline]
 377                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 378                                 writer.write_all(&self.to_be_bytes())
 379                         }
 380                 }
 381                 impl Writeable for HighZeroBytesDroppedBigSize<$val_type> {
 382                         #[inline]
 383                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 384                                 // Skip any full leading 0 bytes when writing (in BE):
 385                                 writer.write_all(&self.0.to_be_bytes()[(self.0.leading_zeros()/8) as usize..$len])
 386                         }
 387                 }
 388                 impl Readable for $val_type {
 389                         #[inline]
 390                         fn read<R: Read>(reader: &mut R) -> Result<$val_type, DecodeError> {
 391                                 let mut buf = [0; $len];
 392                                 reader.read_exact(&mut buf)?;
 393                                 Ok(<$val_type>::from_be_bytes(buf))
 394                         }
 395                 }
 396                 impl Readable for HighZeroBytesDroppedBigSize<$val_type> {
 397                         #[inline]
 398                         fn read<R: Read>(reader: &mut R) -> Result<HighZeroBytesDroppedBigSize<$val_type>, DecodeError> {
 399                                 // We need to accept short reads (read_len == 0) as "EOF" and handle them as simply
 400                                 // the high bytes being dropped. To do so, we start reading into the middle of buf
 401                                 // and then convert the appropriate number of bytes with extra high bytes out of
 402                                 // buf.
 403                                 let mut buf = [0; $len*2];
 404                                 let mut read_len = reader.read(&mut buf[$len..])?;
 405                                 let mut total_read_len = read_len;
 406                                 while read_len != 0 && total_read_len != $len {
 407                                         read_len = reader.read(&mut buf[($len + total_read_len)..])?;
 408                                         total_read_len += read_len;
 409                                 }
 410                                 if total_read_len == 0 || buf[$len] != 0 {
 411                                         let first_byte = $len - ($len - total_read_len);
 412                                         let mut bytes = [0; $len];
 413                                         bytes.copy_from_slice(&buf[first_byte..first_byte + $len]);
 414                                         Ok(HighZeroBytesDroppedBigSize(<$val_type>::from_be_bytes(bytes)))
 415                                 } else {
 416                                         // If the encoding had extra zero bytes, return a failure even though we know
 417                                         // what they meant (as the TLV test vectors require this)
 418                                         Err(DecodeError::InvalidValue)
 419                                 }
 420                         }
 421                 }
 422         }
 423 }
 424
 425 impl_writeable_primitive!(u64, 8);
 426 impl_writeable_primitive!(u32, 4);
 427 impl_writeable_primitive!(u16, 2);
 428
 429 impl Writeable for u8 {
 430         #[inline]
 431         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 432                 writer.write_all(&[*self])
 433         }
 434 }
 435 impl Readable for u8 {
 436         #[inline]
 437         fn read<R: Read>(reader: &mut R) -> Result<u8, DecodeError> {
 438                 let mut buf = [0; 1];
 439                 reader.read_exact(&mut buf)?;
 440                 Ok(buf[0])
 441         }
 442 }
 443
 444 impl Writeable for bool {
 445         #[inline]
 446         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 447                 writer.write_all(&[if *self {1} else {0}])
 448         }
 449 }
 450 impl Readable for bool {
 451         #[inline]
 452         fn read<R: Read>(reader: &mut R) -> Result<bool, DecodeError> {
 453                 let mut buf = [0; 1];
 454                 reader.read_exact(&mut buf)?;
 455                 if buf[0] != 0 && buf[0] != 1 {
 456                         return Err(DecodeError::InvalidValue);
 457                 }
 458                 Ok(buf[0] == 1)
 459         }
 460 }
 461
 462 // u8 arrays
 463 macro_rules! impl_array {
 464         ( $size:expr ) => (
 465                 impl Writeable for [u8; $size]
 466                 {
 467                         #[inline]
 468                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 469                                 w.write_all(self)
 470                         }
 471                 }
 472
 473                 impl Readable for [u8; $size]
 474                 {
 475                         #[inline]
 476                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 477                                 let mut buf = [0u8; $size];
 478                                 r.read_exact(&mut buf)?;
 479                                 Ok(buf)
 480                         }
 481                 }
 482         );
 483 }
 484
 485 impl_array!(3); // for rgb
 486 impl_array!(4); // for IPv4
 487 impl_array!(12); // for OnionV2
 488 impl_array!(16); // for IPv6
 489 impl_array!(32); // for channel id & hmac
 490 impl_array!(PUBLIC_KEY_SIZE); // for PublicKey
 491 impl_array!(COMPACT_SIGNATURE_SIZE); // for Signature
 492 impl_array!(1300); // for OnionPacket.hop_data
 493
 494 impl Writeable for [u16; 8] {
 495         #[inline]
 496         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 497                 for v in self.iter() {
 498                         w.write_all(&v.to_be_bytes())?
 499                 }
 500                 Ok(())
 501         }
 502 }
 503
 504 impl Readable for [u16; 8] {
 505         #[inline]
 506         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 507                 let mut buf = [0u8; 16];
 508                 r.read_exact(&mut buf)?;
 509                 let mut res = [0u16; 8];
 510                 for (idx, v) in res.iter_mut().enumerate() {
 511                         *v = (buf[idx] as u16) << 8 | (buf[idx + 1] as u16)
 512                 }
 513                 Ok(res)
 514         }
 515 }
 516
 517 /// For variable-length values within TLV record where the length is encoded as part of the record.
 518 /// Used to prevent encoding the length twice.
 519 pub(crate) struct WithoutLength<T>(pub T);
 520
 521 impl<'a, T: Writeable> Writeable for WithoutLength<&'a Vec<T>> {
 522         #[inline]
 523         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 524                 for ref v in self.0.iter() {
 525                         v.write(writer)?;
 526                 }
 527                 Ok(())
 528         }
 529 }
 530
 531 impl<T: MaybeReadable> Readable for WithoutLength<Vec<T>> {
 532         #[inline]
 533         fn read<R: Read>(mut reader: &mut R) -> Result<Self, DecodeError> {
 534                 let mut values = Vec::new();
 535                 loop {
 536                         let mut track_read = ReadTrackingReader::new(&mut reader);
 537                         match MaybeReadable::read(&mut track_read) {
 538                                 Ok(Some(v)) => { values.push(v); },
 539                                 Ok(None) => { },
 540                                 // If we failed to read any bytes at all, we reached the end of our TLV
 541                                 // stream and have simply exhausted all entries.
 542                                 Err(ref e) if e == &DecodeError::ShortRead && !track_read.have_read => break,
 543                                 Err(e) => return Err(e),
 544                         }
 545                 }
 546                 Ok(Self(values))
 547         }
 548 }
 549 impl<'a, T> From<&'a Vec<T>> for WithoutLength<&'a Vec<T>> {
 550         fn from(v: &'a Vec<T>) -> Self { Self(v) }
 551 }
 552
 553 // HashMap
 554 impl<K, V> Writeable for HashMap<K, V>
 555         where K: Writeable + Eq + Hash,
 556               V: Writeable
 557 {
 558         #[inline]
 559         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 560         (self.len() as u16).write(w)?;
 561                 for (key, value) in self.iter() {
 562                         key.write(w)?;
 563                         value.write(w)?;
 564                 }
 565                 Ok(())
 566         }
 567 }
 568
 569 impl<K, V> Readable for HashMap<K, V>
 570         where K: Readable + Eq + Hash,
 571               V: MaybeReadable
 572 {
 573         #[inline]
 574         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 575                 let len: u16 = Readable::read(r)?;
 576                 let mut ret = HashMap::with_capacity(len as usize);
 577                 for _ in 0..len {
 578                         let k = K::read(r)?;
 579                         let v_opt = V::read(r)?;
 580                         if let Some(v) = v_opt {
 581                                 if ret.insert(k, v).is_some() {
 582                                         return Err(DecodeError::InvalidValue);
 583                                 }
 584                         }
 585                 }
 586                 Ok(ret)
 587         }
 588 }
 589
 590 // HashSet
 591 impl<T> Writeable for HashSet<T>
 592 where T: Writeable + Eq + Hash
 593 {
 594         #[inline]
 595         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 596                 (self.len() as u16).write(w)?;
 597                 for item in self.iter() {
 598                         item.write(w)?;
 599                 }
 600                 Ok(())
 601         }
 602 }
 603
 604 impl<T> Readable for HashSet<T>
 605 where T: Readable + Eq + Hash
 606 {
 607         #[inline]
 608         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 609                 let len: u16 = Readable::read(r)?;
 610                 let mut ret = HashSet::with_capacity(len as usize);
 611                 for _ in 0..len {
 612                         if !ret.insert(T::read(r)?) {
 613                                 return Err(DecodeError::InvalidValue)
 614                         }
 615                 }
 616                 Ok(ret)
 617         }
 618 }
 619
 620 // Vectors
 621 impl Writeable for Vec<u8> {
 622         #[inline]
 623         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 624                 (self.len() as u16).write(w)?;
 625                 w.write_all(&self)
 626         }
 627 }
 628
 629 impl Readable for Vec<u8> {
 630         #[inline]
 631         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 632                 let len: u16 = Readable::read(r)?;
 633                 let mut ret = Vec::with_capacity(len as usize);
 634                 ret.resize(len as usize, 0);
 635                 r.read_exact(&mut ret)?;
 636                 Ok(ret)
 637         }
 638 }
 639 impl Writeable for Vec<Signature> {
 640         #[inline]
 641         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 642                 (self.len() as u16).write(w)?;
 643                 for e in self.iter() {
 644                         e.write(w)?;
 645                 }
 646                 Ok(())
 647         }
 648 }
 649
 650 impl Readable for Vec<Signature> {
 651         #[inline]
 652         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 653                 let len: u16 = Readable::read(r)?;
 654                 let byte_size = (len as usize)
 655                                 .checked_mul(COMPACT_SIGNATURE_SIZE)
 656                                 .ok_or(DecodeError::BadLengthDescriptor)?;
 657                 if byte_size > MAX_BUF_SIZE {
 658                         return Err(DecodeError::BadLengthDescriptor);
 659                 }
 660                 let mut ret = Vec::with_capacity(len as usize);
 661                 for _ in 0..len { ret.push(Readable::read(r)?); }
 662                 Ok(ret)
 663         }
 664 }
 665
 666 impl Writeable for Script {
 667         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 668                 (self.len() as u16).write(w)?;
 669                 w.write_all(self.as_bytes())
 670         }
 671 }
 672
 673 impl Readable for Script {
 674         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 675                 let len = <u16 as Readable>::read(r)? as usize;
 676                 let mut buf = vec![0; len];
 677                 r.read_exact(&mut buf)?;
 678                 Ok(Script::from(buf))
 679         }
 680 }
 681
 682 impl Writeable for PublicKey {
 683         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 684                 self.serialize().write(w)
 685         }
 686         #[inline]
 687         fn serialized_length(&self) -> usize {
 688                 PUBLIC_KEY_SIZE
 689         }
 690 }
 691
 692 impl Readable for PublicKey {
 693         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 694                 let buf: [u8; PUBLIC_KEY_SIZE] = Readable::read(r)?;
 695                 match PublicKey::from_slice(&buf) {
 696                         Ok(key) => Ok(key),
 697                         Err(_) => return Err(DecodeError::InvalidValue),
 698                 }
 699         }
 700 }
 701
 702 impl Writeable for SecretKey {
 703         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 704                 let mut ser = [0; SECRET_KEY_SIZE];
 705                 ser.copy_from_slice(&self[..]);
 706                 ser.write(w)
 707         }
 708         #[inline]
 709         fn serialized_length(&self) -> usize {
 710                 SECRET_KEY_SIZE
 711         }
 712 }
 713
 714 impl Readable for SecretKey {
 715         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 716                 let buf: [u8; SECRET_KEY_SIZE] = Readable::read(r)?;
 717                 match SecretKey::from_slice(&buf) {
 718                         Ok(key) => Ok(key),
 719                         Err(_) => return Err(DecodeError::InvalidValue),
 720                 }
 721         }
 722 }
 723
 724 impl Writeable for Sha256dHash {
 725         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 726                 w.write_all(&self[..])
 727         }
 728 }
 729
 730 impl Readable for Sha256dHash {
 731         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 732                 use bitcoin::hashes::Hash;
 733
 734                 let buf: [u8; 32] = Readable::read(r)?;
 735                 Ok(Sha256dHash::from_slice(&buf[..]).unwrap())
 736         }
 737 }
 738
 739 impl Writeable for Signature {
 740         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 741                 self.serialize_compact().write(w)
 742         }
 743         #[inline]
 744         fn serialized_length(&self) -> usize {
 745                 COMPACT_SIGNATURE_SIZE
 746         }
 747 }
 748
 749 impl Readable for Signature {
 750         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 751                 let buf: [u8; COMPACT_SIGNATURE_SIZE] = Readable::read(r)?;
 752                 match Signature::from_compact(&buf) {
 753                         Ok(sig) => Ok(sig),
 754                         Err(_) => return Err(DecodeError::InvalidValue),
 755                 }
 756         }
 757 }
 758
 759 impl Writeable for PaymentPreimage {
 760         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 761                 self.0.write(w)
 762         }
 763 }
 764
 765 impl Readable for PaymentPreimage {
 766         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 767                 let buf: [u8; 32] = Readable::read(r)?;
 768                 Ok(PaymentPreimage(buf))
 769         }
 770 }
 771
 772 impl Writeable for PaymentHash {
 773         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 774                 self.0.write(w)
 775         }
 776 }
 777
 778 impl Readable for PaymentHash {
 779         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 780                 let buf: [u8; 32] = Readable::read(r)?;
 781                 Ok(PaymentHash(buf))
 782         }
 783 }
 784
 785 impl Writeable for PaymentSecret {
 786         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 787                 self.0.write(w)
 788         }
 789 }
 790
 791 impl Readable for PaymentSecret {
 792         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 793                 let buf: [u8; 32] = Readable::read(r)?;
 794                 Ok(PaymentSecret(buf))
 795         }
 796 }
 797
 798 impl<T: Writeable> Writeable for Box<T> {
 799         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 800                 T::write(&**self, w)
 801         }
 802 }
 803
 804 impl<T: Readable> Readable for Box<T> {
 805         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 806                 Ok(Box::new(Readable::read(r)?))
 807         }
 808 }
 809
 810 impl<T: Writeable> Writeable for Option<T> {
 811         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 812                 match *self {
 813                         None => 0u8.write(w)?,
 814                         Some(ref data) => {
 815                                 BigSize(data.serialized_length() as u64 + 1).write(w)?;
 816                                 data.write(w)?;
 817                         }
 818                 }
 819                 Ok(())
 820         }
 821 }
 822
 823 impl<T: Readable> Readable for Option<T>
 824 {
 825         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 826                 let len: BigSize = Readable::read(r)?;
 827                 match len.0 {
 828                         0 => Ok(None),
 829                         len => {
 830                                 let mut reader = FixedLengthReader::new(r, len - 1);
 831                                 Ok(Some(Readable::read(&mut reader)?))
 832                         }
 833                 }
 834         }
 835 }
 836
 837 impl Writeable for Txid {
 838         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 839                 w.write_all(&self[..])
 840         }
 841 }
 842
 843 impl Readable for Txid {
 844         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 845                 use bitcoin::hashes::Hash;
 846
 847                 let buf: [u8; 32] = Readable::read(r)?;
 848                 Ok(Txid::from_slice(&buf[..]).unwrap())
 849         }
 850 }
 851
 852 impl Writeable for BlockHash {
 853         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 854                 w.write_all(&self[..])
 855         }
 856 }
 857
 858 impl Readable for BlockHash {
 859         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 860                 use bitcoin::hashes::Hash;
 861
 862                 let buf: [u8; 32] = Readable::read(r)?;
 863                 Ok(BlockHash::from_slice(&buf[..]).unwrap())
 864         }
 865 }
 866
 867 impl Writeable for OutPoint {
 868         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 869                 self.txid.write(w)?;
 870                 self.vout.write(w)?;
 871                 Ok(())
 872         }
 873 }
 874
 875 impl Readable for OutPoint {
 876         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 877                 let txid = Readable::read(r)?;
 878                 let vout = Readable::read(r)?;
 879                 Ok(OutPoint {
 880                         txid,
 881                         vout,
 882                 })
 883         }
 884 }
 885
 886 macro_rules! impl_consensus_ser {
 887         ($bitcoin_type: ty) => {
 888                 impl Writeable for $bitcoin_type {
 889                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 890                                 match self.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 891                                         Ok(_) => Ok(()),
 892                                         Err(e) => Err(e),
 893                                 }
 894                         }
 895                 }
 896
 897                 impl Readable for $bitcoin_type {
 898                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 899                                 match consensus::encode::Decodable::consensus_decode(r) {
 900                                         Ok(t) => Ok(t),
 901                                         Err(consensus::encode::Error::Io(ref e)) if e.kind() == io::ErrorKind::UnexpectedEof => Err(DecodeError::ShortRead),
 902                                         Err(consensus::encode::Error::Io(e)) => Err(DecodeError::Io(e.kind())),
 903                                         Err(_) => Err(DecodeError::InvalidValue),
 904                                 }
 905                         }
 906                 }
 907         }
 908 }
 909 impl_consensus_ser!(Transaction);
 910 impl_consensus_ser!(TxOut);
 911
 912 impl<T: Readable> Readable for Mutex<T> {
 913         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 914                 let t: T = Readable::read(r)?;
 915                 Ok(Mutex::new(t))
 916         }
 917 }
 918 impl<T: Writeable> Writeable for Mutex<T> {
 919         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 920                 self.lock().unwrap().write(w)
 921         }
 922 }
 923
 924 impl<A: Readable, B: Readable> Readable for (A, B) {
 925         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 926                 let a: A = Readable::read(r)?;
 927                 let b: B = Readable::read(r)?;
 928                 Ok((a, b))
 929         }
 930 }
 931 impl<A: Writeable, B: Writeable> Writeable for (A, B) {
 932         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 933                 self.0.write(w)?;
 934                 self.1.write(w)
 935         }
 936 }
 937
 938 impl<A: Readable, B: Readable, C: Readable> Readable for (A, B, C) {
 939         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 940                 let a: A = Readable::read(r)?;
 941                 let b: B = Readable::read(r)?;
 942                 let c: C = Readable::read(r)?;
 943                 Ok((a, b, c))
 944         }
 945 }
 946 impl<A: Writeable, B: Writeable, C: Writeable> Writeable for (A, B, C) {
 947         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 948                 self.0.write(w)?;
 949                 self.1.write(w)?;
 950                 self.2.write(w)
 951         }
 952 }
 953
 954 impl Writeable for () {
 955         fn write<W: Writer>(&self, _: &mut W) -> Result<(), io::Error> {
 956                 Ok(())
 957         }
 958 }
 959 impl Readable for () {
 960         fn read<R: Read>(_r: &mut R) -> Result<Self, DecodeError> {
 961                 Ok(())
 962         }
 963 }
 964
 965 impl Writeable for String {
 966         #[inline]
 967         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 968                 (self.len() as u16).write(w)?;
 969                 w.write_all(self.as_bytes())
 970         }
 971 }
 972 impl Readable for String {
 973         #[inline]
 974         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 975                 let v: Vec<u8> = Readable::read(r)?;
 976                 let ret = String::from_utf8(v).map_err(|_| DecodeError::InvalidValue)?;
 977                 Ok(ret)
 978         }
 979 }
 980
 981 /// Represents a hostname for serialization purposes.
 982 /// Only the character set and length will be validated.
 983 /// The character set consists of ASCII alphanumeric characters, hyphens, and periods.
 984 /// Its length is guaranteed to be representable by a single byte.
 985 /// This serialization is used by BOLT 7 hostnames.
 986 #[derive(Clone, Debug, PartialEq, Eq)]
 987 pub struct Hostname(String);
 988 impl Hostname {
 989         /// Returns the length of the hostname.
 990         pub fn len(&self) -> u8 {
 991                 (&self.0).len() as u8
 992         }
 993 }
 994 impl Deref for Hostname {
 995         type Target = String;
 996
 997         fn deref(&self) -> &Self::Target {
 998                 &self.0
 999         }
1000 }
1001 impl From<Hostname> for String {
1002         fn from(hostname: Hostname) -> Self {
1003                 hostname.0
1004         }
1005 }
1006 impl TryFrom<Vec<u8>> for Hostname {
1007         type Error = ();
1008
1009         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1010                 if let Ok(s) = String::from_utf8(bytes) {
1011                         Hostname::try_from(s)
1012                 } else {
1013                         Err(())
1014                 }
1015         }
1016 }
1017 impl TryFrom<String> for Hostname {
1018         type Error = ();
1019
1020         fn try_from(s: String) -> Result<Self, Self::Error> {
1021                 if s.len() <= 255 && s.chars().all(|c|
1022                         c.is_ascii_alphanumeric() ||
1023                         c == '.' ||
1024                         c == '-'
1025                 ) {
1026                         Ok(Hostname(s))
1027                 } else {
1028                         Err(())
1029                 }
1030         }
1031 }
1032 impl Writeable for Hostname {
1033         #[inline]
1034         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1035                 self.len().write(w)?;
1036                 w.write_all(self.as_bytes())
1037         }
1038 }
1039 impl Readable for Hostname {
1040         #[inline]
1041         fn read<R: Read>(r: &mut R) -> Result<Hostname, DecodeError> {
1042                 let len: u8 = Readable::read(r)?;
1043                 let mut vec = Vec::with_capacity(len.into());
1044                 vec.resize(len.into(), 0);
1045                 r.read_exact(&mut vec)?;
1046                 Hostname::try_from(vec).map_err(|_| DecodeError::InvalidValue)
1047         }
1048 }
1049
1050 impl Writeable for Duration {
1051         #[inline]
1052         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1053                 self.as_secs().write(w)?;
1054                 self.subsec_nanos().write(w)
1055         }
1056 }
1057 impl Readable for Duration {
1058         #[inline]
1059         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1060                 let secs = Readable::read(r)?;
1061                 let nanos = Readable::read(r)?;
1062                 Ok(Duration::new(secs, nanos))
1063         }
1064 }
1065
1066 #[cfg(test)]
1067 mod tests {
1068         use core::convert::TryFrom;
1069         use crate::util::ser::{Readable, Hostname, Writeable};
1070
1071         #[test]
1072         fn hostname_conversion() {
1073                 assert_eq!(Hostname::try_from(String::from("a-test.com")).unwrap().as_str(), "a-test.com");
1074
1075                 assert!(Hostname::try_from(String::from("\"")).is_err());
1076                 assert!(Hostname::try_from(String::from("$")).is_err());
1077                 assert!(Hostname::try_from(String::from("⚡")).is_err());
1078                 let mut large_vec = Vec::with_capacity(256);
1079                 large_vec.resize(256, b'A');
1080                 assert!(Hostname::try_from(String::from_utf8(large_vec).unwrap()).is_err());
1081         }
1082
1083         #[test]
1084         fn hostname_serialization() {
1085                 let hostname = Hostname::try_from(String::from("test")).unwrap();
1086                 let mut buf: Vec<u8> = Vec::new();
1087                 hostname.write(&mut buf).unwrap();
1088                 assert_eq!(Hostname::read(&mut buf.as_slice()).unwrap().as_str(), "test");
1089         }
1090 }