git.bitcoin.ninja 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 /// Wrapper to write each element of a Vec with no length prefix
 287 pub(crate) struct VecWriteWrapper<'a, T: Writeable>(pub &'a Vec<T>);
 288 impl<'a, T: Writeable> Writeable for VecWriteWrapper<'a, T> {
 289         #[inline]
 290         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 291                 for ref v in self.0.iter() {
 292                         v.write(writer)?;
 293                 }
 294                 Ok(())
 295         }
 296 }
 297
 298 /// Wrapper to read elements from a given stream until it reaches the end of the stream.
 299 pub(crate) struct VecReadWrapper<T>(pub Vec<T>);
 300 impl<T: MaybeReadable> Readable for VecReadWrapper<T> {
 301         #[inline]
 302         fn read<R: Read>(mut reader: &mut R) -> Result<Self, DecodeError> {
 303                 let mut values = Vec::new();
 304                 loop {
 305                         let mut track_read = ReadTrackingReader::new(&mut reader);
 306                         match MaybeReadable::read(&mut track_read) {
 307                                 Ok(Some(v)) => { values.push(v); },
 308                                 Ok(None) => { },
 309                                 // If we failed to read any bytes at all, we reached the end of our TLV
 310                                 // stream and have simply exhausted all entries.
 311                                 Err(ref e) if e == &DecodeError::ShortRead && !track_read.have_read => break,
 312                                 Err(e) => return Err(e),
 313                         }
 314                 }
 315                 Ok(Self(values))
 316         }
 317 }
 318
 319 pub(crate) struct U48(pub u64);
 320 impl Writeable for U48 {
 321         #[inline]
 322         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 323                 writer.write_all(&be48_to_array(self.0))
 324         }
 325 }
 326 impl Readable for U48 {
 327         #[inline]
 328         fn read<R: Read>(reader: &mut R) -> Result<U48, DecodeError> {
 329                 let mut buf = [0; 6];
 330                 reader.read_exact(&mut buf)?;
 331                 Ok(U48(slice_to_be48(&buf)))
 332         }
 333 }
 334
 335 /// Lightning TLV uses a custom variable-length integer called BigSize. It is similar to Bitcoin's
 336 /// variable-length integers except that it is serialized in big-endian instead of little-endian.
 337 ///
 338 /// Like Bitcoin's variable-length integer, it exhibits ambiguity in that certain values can be
 339 /// encoded in several different ways, which we must check for at deserialization-time. Thus, if
 340 /// you're looking for an example of a variable-length integer to use for your own project, move
 341 /// along, this is a rather poor design.
 342 pub struct BigSize(pub u64);
 343 impl Writeable for BigSize {
 344         #[inline]
 345         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 346                 match self.0 {
 347                         0...0xFC => {
 348                                 (self.0 as u8).write(writer)
 349                         },
 350                         0xFD...0xFFFF => {
 351                                 0xFDu8.write(writer)?;
 352                                 (self.0 as u16).write(writer)
 353                         },
 354                         0x10000...0xFFFFFFFF => {
 355                                 0xFEu8.write(writer)?;
 356                                 (self.0 as u32).write(writer)
 357                         },
 358                         _ => {
 359                                 0xFFu8.write(writer)?;
 360                                 (self.0 as u64).write(writer)
 361                         },
 362                 }
 363         }
 364 }
 365 impl Readable for BigSize {
 366         #[inline]
 367         fn read<R: Read>(reader: &mut R) -> Result<BigSize, DecodeError> {
 368                 let n: u8 = Readable::read(reader)?;
 369                 match n {
 370                         0xFF => {
 371                                 let x: u64 = Readable::read(reader)?;
 372                                 if x < 0x100000000 {
 373                                         Err(DecodeError::InvalidValue)
 374                                 } else {
 375                                         Ok(BigSize(x))
 376                                 }
 377                         }
 378                         0xFE => {
 379                                 let x: u32 = Readable::read(reader)?;
 380                                 if x < 0x10000 {
 381                                         Err(DecodeError::InvalidValue)
 382                                 } else {
 383                                         Ok(BigSize(x as u64))
 384                                 }
 385                         }
 386                         0xFD => {
 387                                 let x: u16 = Readable::read(reader)?;
 388                                 if x < 0xFD {
 389                                         Err(DecodeError::InvalidValue)
 390                                 } else {
 391                                         Ok(BigSize(x as u64))
 392                                 }
 393                         }
 394                         n => Ok(BigSize(n as u64))
 395                 }
 396         }
 397 }
 398
 399 /// In TLV we occasionally send fields which only consist of, or potentially end with, a
 400 /// variable-length integer which is simply truncated by skipping high zero bytes. This type
 401 /// encapsulates such integers implementing Readable/Writeable for them.
 402 #[cfg_attr(test, derive(PartialEq, Eq))]
 403 #[derive(Clone, Debug)]
 404 pub(crate) struct HighZeroBytesDroppedBigSize<T>(pub T);
 405
 406 macro_rules! impl_writeable_primitive {
 407         ($val_type:ty, $len: expr) => {
 408                 impl Writeable for $val_type {
 409                         #[inline]
 410                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 411                                 writer.write_all(&self.to_be_bytes())
 412                         }
 413                 }
 414                 impl Writeable for HighZeroBytesDroppedBigSize<$val_type> {
 415                         #[inline]
 416                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 417                                 // Skip any full leading 0 bytes when writing (in BE):
 418                                 writer.write_all(&self.0.to_be_bytes()[(self.0.leading_zeros()/8) as usize..$len])
 419                         }
 420                 }
 421                 impl Readable for $val_type {
 422                         #[inline]
 423                         fn read<R: Read>(reader: &mut R) -> Result<$val_type, DecodeError> {
 424                                 let mut buf = [0; $len];
 425                                 reader.read_exact(&mut buf)?;
 426                                 Ok(<$val_type>::from_be_bytes(buf))
 427                         }
 428                 }
 429                 impl Readable for HighZeroBytesDroppedBigSize<$val_type> {
 430                         #[inline]
 431                         fn read<R: Read>(reader: &mut R) -> Result<HighZeroBytesDroppedBigSize<$val_type>, DecodeError> {
 432                                 // We need to accept short reads (read_len == 0) as "EOF" and handle them as simply
 433                                 // the high bytes being dropped. To do so, we start reading into the middle of buf
 434                                 // and then convert the appropriate number of bytes with extra high bytes out of
 435                                 // buf.
 436                                 let mut buf = [0; $len*2];
 437                                 let mut read_len = reader.read(&mut buf[$len..])?;
 438                                 let mut total_read_len = read_len;
 439                                 while read_len != 0 && total_read_len != $len {
 440                                         read_len = reader.read(&mut buf[($len + total_read_len)..])?;
 441                                         total_read_len += read_len;
 442                                 }
 443                                 if total_read_len == 0 || buf[$len] != 0 {
 444                                         let first_byte = $len - ($len - total_read_len);
 445                                         let mut bytes = [0; $len];
 446                                         bytes.copy_from_slice(&buf[first_byte..first_byte + $len]);
 447                                         Ok(HighZeroBytesDroppedBigSize(<$val_type>::from_be_bytes(bytes)))
 448                                 } else {
 449                                         // If the encoding had extra zero bytes, return a failure even though we know
 450                                         // what they meant (as the TLV test vectors require this)
 451                                         Err(DecodeError::InvalidValue)
 452                                 }
 453                         }
 454                 }
 455         }
 456 }
 457
 458 impl_writeable_primitive!(u64, 8);
 459 impl_writeable_primitive!(u32, 4);
 460 impl_writeable_primitive!(u16, 2);
 461
 462 impl Writeable for u8 {
 463         #[inline]
 464         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 465                 writer.write_all(&[*self])
 466         }
 467 }
 468 impl Readable for u8 {
 469         #[inline]
 470         fn read<R: Read>(reader: &mut R) -> Result<u8, DecodeError> {
 471                 let mut buf = [0; 1];
 472                 reader.read_exact(&mut buf)?;
 473                 Ok(buf[0])
 474         }
 475 }
 476
 477 impl Writeable for bool {
 478         #[inline]
 479         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 480                 writer.write_all(&[if *self {1} else {0}])
 481         }
 482 }
 483 impl Readable for bool {
 484         #[inline]
 485         fn read<R: Read>(reader: &mut R) -> Result<bool, DecodeError> {
 486                 let mut buf = [0; 1];
 487                 reader.read_exact(&mut buf)?;
 488                 if buf[0] != 0 && buf[0] != 1 {
 489                         return Err(DecodeError::InvalidValue);
 490                 }
 491                 Ok(buf[0] == 1)
 492         }
 493 }
 494
 495 // u8 arrays
 496 macro_rules! impl_array {
 497         ( $size:expr ) => (
 498                 impl Writeable for [u8; $size]
 499                 {
 500                         #[inline]
 501                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 502                                 w.write_all(self)
 503                         }
 504                 }
 505
 506                 impl Readable for [u8; $size]
 507                 {
 508                         #[inline]
 509                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 510                                 let mut buf = [0u8; $size];
 511                                 r.read_exact(&mut buf)?;
 512                                 Ok(buf)
 513                         }
 514                 }
 515         );
 516 }
 517
 518 impl_array!(3); // for rgb
 519 impl_array!(4); // for IPv4
 520 impl_array!(12); // for OnionV2
 521 impl_array!(16); // for IPv6
 522 impl_array!(32); // for channel id & hmac
 523 impl_array!(PUBLIC_KEY_SIZE); // for PublicKey
 524 impl_array!(COMPACT_SIGNATURE_SIZE); // for Signature
 525 impl_array!(1300); // for OnionPacket.hop_data
 526
 527 impl Writeable for [u16; 8] {
 528         #[inline]
 529         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 530                 for v in self.iter() {
 531                         w.write_all(&v.to_be_bytes())?
 532                 }
 533                 Ok(())
 534         }
 535 }
 536
 537 impl Readable for [u16; 8] {
 538         #[inline]
 539         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 540                 let mut buf = [0u8; 16];
 541                 r.read_exact(&mut buf)?;
 542                 let mut res = [0u16; 8];
 543                 for (idx, v) in res.iter_mut().enumerate() {
 544                         *v = (buf[idx] as u16) << 8 | (buf[idx + 1] as u16)
 545                 }
 546                 Ok(res)
 547         }
 548 }
 549
 550 // HashMap
 551 impl<K, V> Writeable for HashMap<K, V>
 552         where K: Writeable + Eq + Hash,
 553               V: Writeable
 554 {
 555         #[inline]
 556         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 557         (self.len() as u16).write(w)?;
 558                 for (key, value) in self.iter() {
 559                         key.write(w)?;
 560                         value.write(w)?;
 561                 }
 562                 Ok(())
 563         }
 564 }
 565
 566 impl<K, V> Readable for HashMap<K, V>
 567         where K: Readable + Eq + Hash,
 568               V: MaybeReadable
 569 {
 570         #[inline]
 571         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 572                 let len: u16 = Readable::read(r)?;
 573                 let mut ret = HashMap::with_capacity(len as usize);
 574                 for _ in 0..len {
 575                         let k = K::read(r)?;
 576                         let v_opt = V::read(r)?;
 577                         if let Some(v) = v_opt {
 578                                 if ret.insert(k, v).is_some() {
 579                                         return Err(DecodeError::InvalidValue);
 580                                 }
 581                         }
 582                 }
 583                 Ok(ret)
 584         }
 585 }
 586
 587 // HashSet
 588 impl<T> Writeable for HashSet<T>
 589 where T: Writeable + Eq + Hash
 590 {
 591         #[inline]
 592         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 593                 (self.len() as u16).write(w)?;
 594                 for item in self.iter() {
 595                         item.write(w)?;
 596                 }
 597                 Ok(())
 598         }
 599 }
 600
 601 impl<T> Readable for HashSet<T>
 602 where T: Readable + Eq + Hash
 603 {
 604         #[inline]
 605         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 606                 let len: u16 = Readable::read(r)?;
 607                 let mut ret = HashSet::with_capacity(len as usize);
 608                 for _ in 0..len {
 609                         if !ret.insert(T::read(r)?) {
 610                                 return Err(DecodeError::InvalidValue)
 611                         }
 612                 }
 613                 Ok(ret)
 614         }
 615 }
 616
 617 // Vectors
 618 impl Writeable for Vec<u8> {
 619         #[inline]
 620         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 621                 (self.len() as u16).write(w)?;
 622                 w.write_all(&self)
 623         }
 624 }
 625
 626 impl Readable for Vec<u8> {
 627         #[inline]
 628         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 629                 let len: u16 = Readable::read(r)?;
 630                 let mut ret = Vec::with_capacity(len as usize);
 631                 ret.resize(len as usize, 0);
 632                 r.read_exact(&mut ret)?;
 633                 Ok(ret)
 634         }
 635 }
 636 impl Writeable for Vec<Signature> {
 637         #[inline]
 638         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 639                 (self.len() as u16).write(w)?;
 640                 for e in self.iter() {
 641                         e.write(w)?;
 642                 }
 643                 Ok(())
 644         }
 645 }
 646
 647 impl Readable for Vec<Signature> {
 648         #[inline]
 649         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 650                 let len: u16 = Readable::read(r)?;
 651                 let byte_size = (len as usize)
 652                                 .checked_mul(COMPACT_SIGNATURE_SIZE)
 653                                 .ok_or(DecodeError::BadLengthDescriptor)?;
 654                 if byte_size > MAX_BUF_SIZE {
 655                         return Err(DecodeError::BadLengthDescriptor);
 656                 }
 657                 let mut ret = Vec::with_capacity(len as usize);
 658                 for _ in 0..len { ret.push(Readable::read(r)?); }
 659                 Ok(ret)
 660         }
 661 }
 662
 663 impl Writeable for Script {
 664         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 665                 (self.len() as u16).write(w)?;
 666                 w.write_all(self.as_bytes())
 667         }
 668 }
 669
 670 impl Readable for Script {
 671         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 672                 let len = <u16 as Readable>::read(r)? as usize;
 673                 let mut buf = vec![0; len];
 674                 r.read_exact(&mut buf)?;
 675                 Ok(Script::from(buf))
 676         }
 677 }
 678
 679 impl Writeable for PublicKey {
 680         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 681                 self.serialize().write(w)
 682         }
 683         #[inline]
 684         fn serialized_length(&self) -> usize {
 685                 PUBLIC_KEY_SIZE
 686         }
 687 }
 688
 689 impl Readable for PublicKey {
 690         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 691                 let buf: [u8; PUBLIC_KEY_SIZE] = Readable::read(r)?;
 692                 match PublicKey::from_slice(&buf) {
 693                         Ok(key) => Ok(key),
 694                         Err(_) => return Err(DecodeError::InvalidValue),
 695                 }
 696         }
 697 }
 698
 699 impl Writeable for SecretKey {
 700         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 701                 let mut ser = [0; SECRET_KEY_SIZE];
 702                 ser.copy_from_slice(&self[..]);
 703                 ser.write(w)
 704         }
 705         #[inline]
 706         fn serialized_length(&self) -> usize {
 707                 SECRET_KEY_SIZE
 708         }
 709 }
 710
 711 impl Readable for SecretKey {
 712         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 713                 let buf: [u8; SECRET_KEY_SIZE] = Readable::read(r)?;
 714                 match SecretKey::from_slice(&buf) {
 715                         Ok(key) => Ok(key),
 716                         Err(_) => return Err(DecodeError::InvalidValue),
 717                 }
 718         }
 719 }
 720
 721 impl Writeable for Sha256dHash {
 722         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 723                 w.write_all(&self[..])
 724         }
 725 }
 726
 727 impl Readable for Sha256dHash {
 728         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 729                 use bitcoin::hashes::Hash;
 730
 731                 let buf: [u8; 32] = Readable::read(r)?;
 732                 Ok(Sha256dHash::from_slice(&buf[..]).unwrap())
 733         }
 734 }
 735
 736 impl Writeable for Signature {
 737         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 738                 self.serialize_compact().write(w)
 739         }
 740         #[inline]
 741         fn serialized_length(&self) -> usize {
 742                 COMPACT_SIGNATURE_SIZE
 743         }
 744 }
 745
 746 impl Readable for Signature {
 747         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 748                 let buf: [u8; COMPACT_SIGNATURE_SIZE] = Readable::read(r)?;
 749                 match Signature::from_compact(&buf) {
 750                         Ok(sig) => Ok(sig),
 751                         Err(_) => return Err(DecodeError::InvalidValue),
 752                 }
 753         }
 754 }
 755
 756 impl Writeable for PaymentPreimage {
 757         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 758                 self.0.write(w)
 759         }
 760 }
 761
 762 impl Readable for PaymentPreimage {
 763         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 764                 let buf: [u8; 32] = Readable::read(r)?;
 765                 Ok(PaymentPreimage(buf))
 766         }
 767 }
 768
 769 impl Writeable for PaymentHash {
 770         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 771                 self.0.write(w)
 772         }
 773 }
 774
 775 impl Readable for PaymentHash {
 776         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 777                 let buf: [u8; 32] = Readable::read(r)?;
 778                 Ok(PaymentHash(buf))
 779         }
 780 }
 781
 782 impl Writeable for PaymentSecret {
 783         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 784                 self.0.write(w)
 785         }
 786 }
 787
 788 impl Readable for PaymentSecret {
 789         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 790                 let buf: [u8; 32] = Readable::read(r)?;
 791                 Ok(PaymentSecret(buf))
 792         }
 793 }
 794
 795 impl<T: Writeable> Writeable for Box<T> {
 796         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 797                 T::write(&**self, w)
 798         }
 799 }
 800
 801 impl<T: Readable> Readable for Box<T> {
 802         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 803                 Ok(Box::new(Readable::read(r)?))
 804         }
 805 }
 806
 807 impl<T: Writeable> Writeable for Option<T> {
 808         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 809                 match *self {
 810                         None => 0u8.write(w)?,
 811                         Some(ref data) => {
 812                                 BigSize(data.serialized_length() as u64 + 1).write(w)?;
 813                                 data.write(w)?;
 814                         }
 815                 }
 816                 Ok(())
 817         }
 818 }
 819
 820 impl<T: Readable> Readable for Option<T>
 821 {
 822         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 823                 let len: BigSize = Readable::read(r)?;
 824                 match len.0 {
 825                         0 => Ok(None),
 826                         len => {
 827                                 let mut reader = FixedLengthReader::new(r, len - 1);
 828                                 Ok(Some(Readable::read(&mut reader)?))
 829                         }
 830                 }
 831         }
 832 }
 833
 834 impl Writeable for Txid {
 835         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 836                 w.write_all(&self[..])
 837         }
 838 }
 839
 840 impl Readable for Txid {
 841         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 842                 use bitcoin::hashes::Hash;
 843
 844                 let buf: [u8; 32] = Readable::read(r)?;
 845                 Ok(Txid::from_slice(&buf[..]).unwrap())
 846         }
 847 }
 848
 849 impl Writeable for BlockHash {
 850         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 851                 w.write_all(&self[..])
 852         }
 853 }
 854
 855 impl Readable for BlockHash {
 856         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 857                 use bitcoin::hashes::Hash;
 858
 859                 let buf: [u8; 32] = Readable::read(r)?;
 860                 Ok(BlockHash::from_slice(&buf[..]).unwrap())
 861         }
 862 }
 863
 864 impl Writeable for OutPoint {
 865         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 866                 self.txid.write(w)?;
 867                 self.vout.write(w)?;
 868                 Ok(())
 869         }
 870 }
 871
 872 impl Readable for OutPoint {
 873         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 874                 let txid = Readable::read(r)?;
 875                 let vout = Readable::read(r)?;
 876                 Ok(OutPoint {
 877                         txid,
 878                         vout,
 879                 })
 880         }
 881 }
 882
 883 macro_rules! impl_consensus_ser {
 884         ($bitcoin_type: ty) => {
 885                 impl Writeable for $bitcoin_type {
 886                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 887                                 match self.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 888                                         Ok(_) => Ok(()),
 889                                         Err(e) => Err(e),
 890                                 }
 891                         }
 892                 }
 893
 894                 impl Readable for $bitcoin_type {
 895                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 896                                 match consensus::encode::Decodable::consensus_decode(r) {
 897                                         Ok(t) => Ok(t),
 898                                         Err(consensus::encode::Error::Io(ref e)) if e.kind() == io::ErrorKind::UnexpectedEof => Err(DecodeError::ShortRead),
 899                                         Err(consensus::encode::Error::Io(e)) => Err(DecodeError::Io(e.kind())),
 900                                         Err(_) => Err(DecodeError::InvalidValue),
 901                                 }
 902                         }
 903                 }
 904         }
 905 }
 906 impl_consensus_ser!(Transaction);
 907 impl_consensus_ser!(TxOut);
 908
 909 impl<T: Readable> Readable for Mutex<T> {
 910         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 911                 let t: T = Readable::read(r)?;
 912                 Ok(Mutex::new(t))
 913         }
 914 }
 915 impl<T: Writeable> Writeable for Mutex<T> {
 916         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 917                 self.lock().unwrap().write(w)
 918         }
 919 }
 920
 921 impl<A: Readable, B: Readable> Readable for (A, B) {
 922         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 923                 let a: A = Readable::read(r)?;
 924                 let b: B = Readable::read(r)?;
 925                 Ok((a, b))
 926         }
 927 }
 928 impl<A: Writeable, B: Writeable> Writeable for (A, B) {
 929         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 930                 self.0.write(w)?;
 931                 self.1.write(w)
 932         }
 933 }
 934
 935 impl<A: Readable, B: Readable, C: Readable> Readable for (A, B, C) {
 936         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 937                 let a: A = Readable::read(r)?;
 938                 let b: B = Readable::read(r)?;
 939                 let c: C = Readable::read(r)?;
 940                 Ok((a, b, c))
 941         }
 942 }
 943 impl<A: Writeable, B: Writeable, C: Writeable> Writeable for (A, B, C) {
 944         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 945                 self.0.write(w)?;
 946                 self.1.write(w)?;
 947                 self.2.write(w)
 948         }
 949 }
 950
 951 impl Writeable for () {
 952         fn write<W: Writer>(&self, _: &mut W) -> Result<(), io::Error> {
 953                 Ok(())
 954         }
 955 }
 956 impl Readable for () {
 957         fn read<R: Read>(_r: &mut R) -> Result<Self, DecodeError> {
 958                 Ok(())
 959         }
 960 }
 961
 962 impl Writeable for String {
 963         #[inline]
 964         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 965                 (self.len() as u16).write(w)?;
 966                 w.write_all(self.as_bytes())
 967         }
 968 }
 969 impl Readable for String {
 970         #[inline]
 971         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 972                 let v: Vec<u8> = Readable::read(r)?;
 973                 let ret = String::from_utf8(v).map_err(|_| DecodeError::InvalidValue)?;
 974                 Ok(ret)
 975         }
 976 }
 977
 978 /// Represents a hostname for serialization purposes.
 979 /// Only the character set and length will be validated.
 980 /// The character set consists of ASCII alphanumeric characters, hyphens, and periods.
 981 /// Its length is guaranteed to be representable by a single byte.
 982 /// This serialization is used by BOLT 7 hostnames.
 983 #[derive(Clone, Debug, PartialEq, Eq)]
 984 pub struct Hostname(String);
 985 impl Hostname {
 986         /// Returns the length of the hostname.
 987         pub fn len(&self) -> u8 {
 988                 (&self.0).len() as u8
 989         }
 990 }
 991 impl Deref for Hostname {
 992         type Target = String;
 993
 994         fn deref(&self) -> &Self::Target {
 995                 &self.0
 996         }
 997 }
 998 impl From<Hostname> for String {
 999         fn from(hostname: Hostname) -> Self {
1000                 hostname.0
1001         }
1002 }
1003 impl TryFrom<Vec<u8>> for Hostname {
1004         type Error = ();
1005
1006         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1007                 if let Ok(s) = String::from_utf8(bytes) {
1008                         Hostname::try_from(s)
1009                 } else {
1010                         Err(())
1011                 }
1012         }
1013 }
1014 impl TryFrom<String> for Hostname {
1015         type Error = ();
1016
1017         fn try_from(s: String) -> Result<Self, Self::Error> {
1018                 if s.len() <= 255 && s.chars().all(|c|
1019                         c.is_ascii_alphanumeric() ||
1020                         c == '.' ||
1021                         c == '-'
1022                 ) {
1023                         Ok(Hostname(s))
1024                 } else {
1025                         Err(())
1026                 }
1027         }
1028 }
1029 impl Writeable for Hostname {
1030         #[inline]
1031         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1032                 self.len().write(w)?;
1033                 w.write_all(self.as_bytes())
1034         }
1035 }
1036 impl Readable for Hostname {
1037         #[inline]
1038         fn read<R: Read>(r: &mut R) -> Result<Hostname, DecodeError> {
1039                 let len: u8 = Readable::read(r)?;
1040                 let mut vec = Vec::with_capacity(len.into());
1041                 vec.resize(len.into(), 0);
1042                 r.read_exact(&mut vec)?;
1043                 Hostname::try_from(vec).map_err(|_| DecodeError::InvalidValue)
1044         }
1045 }
1046
1047 impl Writeable for Duration {
1048         #[inline]
1049         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1050                 self.as_secs().write(w)?;
1051                 self.subsec_nanos().write(w)
1052         }
1053 }
1054 impl Readable for Duration {
1055         #[inline]
1056         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1057                 let secs = Readable::read(r)?;
1058                 let nanos = Readable::read(r)?;
1059                 Ok(Duration::new(secs, nanos))
1060         }
1061 }
1062
1063 #[cfg(test)]
1064 mod tests {
1065         use core::convert::TryFrom;
1066         use crate::util::ser::{Readable, Hostname, Writeable};
1067
1068         #[test]
1069         fn hostname_conversion() {
1070                 assert_eq!(Hostname::try_from(String::from("a-test.com")).unwrap().as_str(), "a-test.com");
1071
1072                 assert!(Hostname::try_from(String::from("\"")).is_err());
1073                 assert!(Hostname::try_from(String::from("$")).is_err());
1074                 assert!(Hostname::try_from(String::from("⚡")).is_err());
1075                 let mut large_vec = Vec::with_capacity(256);
1076                 large_vec.resize(256, b'A');
1077                 assert!(Hostname::try_from(String::from_utf8(large_vec).unwrap()).is_err());
1078         }
1079
1080         #[test]
1081         fn hostname_serialization() {
1082                 let hostname = Hostname::try_from(String::from("test")).unwrap();
1083                 let mut buf: Vec<u8> = Vec::new();
1084                 hostname.write(&mut buf).unwrap();
1085                 assert_eq!(Hostname::read(&mut buf.as_slice()).unwrap().as_str(), "test");
1086         }
1087 }