_ 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 prelude::*;
  14 use io::{self, Read, Write};
  15 use io_extras::{copy, sink};
  16 use core::hash::Hash;
  17 use 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 ln::msgs::DecodeError;
  34 use ln::{PaymentPreimage, PaymentHash, PaymentSecret};
  35
  36 use 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 rust-lightning types implement allowing them to (maybe) be read in from a Read
 248 ///
 249 /// (C-not exported) as we only export serialization to/from byte arrays instead
 250 pub trait MaybeReadable
 251         where Self: Sized
 252 {
 253         /// Reads a Self in from the given Read
 254         fn read<R: Read>(reader: &mut R) -> Result<Option<Self>, DecodeError>;
 255 }
 256
 257 impl<T: Readable> MaybeReadable for T {
 258         #[inline]
 259         fn read<R: Read>(reader: &mut R) -> Result<Option<T>, DecodeError> {
 260                 Ok(Some(Readable::read(reader)?))
 261         }
 262 }
 263
 264 pub(crate) struct OptionDeserWrapper<T: Readable>(pub Option<T>);
 265 impl<T: Readable> Readable for OptionDeserWrapper<T> {
 266         #[inline]
 267         fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
 268                 Ok(Self(Some(Readable::read(reader)?)))
 269         }
 270 }
 271 /// When handling default_values, we want to map the default-value T directly
 272 /// to a OptionDeserWrapper<T> in a way that works for `field: T = t;` as
 273 /// well. Thus, we assume `Into<T> for T` does nothing and use that.
 274 impl<T: Readable> From<T> for OptionDeserWrapper<T> {
 275         fn from(t: T) -> OptionDeserWrapper<T> { OptionDeserWrapper(Some(t)) }
 276 }
 277
 278 /// Wrapper to write each element of a Vec with no length prefix
 279 pub(crate) struct VecWriteWrapper<'a, T: Writeable>(pub &'a Vec<T>);
 280 impl<'a, T: Writeable> Writeable for VecWriteWrapper<'a, T> {
 281         #[inline]
 282         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 283                 for ref v in self.0.iter() {
 284                         v.write(writer)?;
 285                 }
 286                 Ok(())
 287         }
 288 }
 289
 290 /// Wrapper to read elements from a given stream until it reaches the end of the stream.
 291 pub(crate) struct VecReadWrapper<T>(pub Vec<T>);
 292 impl<T: MaybeReadable> Readable for VecReadWrapper<T> {
 293         #[inline]
 294         fn read<R: Read>(mut reader: &mut R) -> Result<Self, DecodeError> {
 295                 let mut values = Vec::new();
 296                 loop {
 297                         let mut track_read = ReadTrackingReader::new(&mut reader);
 298                         match MaybeReadable::read(&mut track_read) {
 299                                 Ok(Some(v)) => { values.push(v); },
 300                                 Ok(None) => { },
 301                                 // If we failed to read any bytes at all, we reached the end of our TLV
 302                                 // stream and have simply exhausted all entries.
 303                                 Err(ref e) if e == &DecodeError::ShortRead && !track_read.have_read => break,
 304                                 Err(e) => return Err(e),
 305                         }
 306                 }
 307                 Ok(Self(values))
 308         }
 309 }
 310
 311 pub(crate) struct U48(pub u64);
 312 impl Writeable for U48 {
 313         #[inline]
 314         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 315                 writer.write_all(&be48_to_array(self.0))
 316         }
 317 }
 318 impl Readable for U48 {
 319         #[inline]
 320         fn read<R: Read>(reader: &mut R) -> Result<U48, DecodeError> {
 321                 let mut buf = [0; 6];
 322                 reader.read_exact(&mut buf)?;
 323                 Ok(U48(slice_to_be48(&buf)))
 324         }
 325 }
 326
 327 /// Lightning TLV uses a custom variable-length integer called BigSize. It is similar to Bitcoin's
 328 /// variable-length integers except that it is serialized in big-endian instead of little-endian.
 329 ///
 330 /// Like Bitcoin's variable-length integer, it exhibits ambiguity in that certain values can be
 331 /// encoded in several different ways, which we must check for at deserialization-time. Thus, if
 332 /// you're looking for an example of a variable-length integer to use for your own project, move
 333 /// along, this is a rather poor design.
 334 pub struct BigSize(pub u64);
 335 impl Writeable for BigSize {
 336         #[inline]
 337         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 338                 match self.0 {
 339                         0...0xFC => {
 340                                 (self.0 as u8).write(writer)
 341                         },
 342                         0xFD...0xFFFF => {
 343                                 0xFDu8.write(writer)?;
 344                                 (self.0 as u16).write(writer)
 345                         },
 346                         0x10000...0xFFFFFFFF => {
 347                                 0xFEu8.write(writer)?;
 348                                 (self.0 as u32).write(writer)
 349                         },
 350                         _ => {
 351                                 0xFFu8.write(writer)?;
 352                                 (self.0 as u64).write(writer)
 353                         },
 354                 }
 355         }
 356 }
 357 impl Readable for BigSize {
 358         #[inline]
 359         fn read<R: Read>(reader: &mut R) -> Result<BigSize, DecodeError> {
 360                 let n: u8 = Readable::read(reader)?;
 361                 match n {
 362                         0xFF => {
 363                                 let x: u64 = Readable::read(reader)?;
 364                                 if x < 0x100000000 {
 365                                         Err(DecodeError::InvalidValue)
 366                                 } else {
 367                                         Ok(BigSize(x))
 368                                 }
 369                         }
 370                         0xFE => {
 371                                 let x: u32 = Readable::read(reader)?;
 372                                 if x < 0x10000 {
 373                                         Err(DecodeError::InvalidValue)
 374                                 } else {
 375                                         Ok(BigSize(x as u64))
 376                                 }
 377                         }
 378                         0xFD => {
 379                                 let x: u16 = Readable::read(reader)?;
 380                                 if x < 0xFD {
 381                                         Err(DecodeError::InvalidValue)
 382                                 } else {
 383                                         Ok(BigSize(x as u64))
 384                                 }
 385                         }
 386                         n => Ok(BigSize(n as u64))
 387                 }
 388         }
 389 }
 390
 391 /// In TLV we occasionally send fields which only consist of, or potentially end with, a
 392 /// variable-length integer which is simply truncated by skipping high zero bytes. This type
 393 /// encapsulates such integers implementing Readable/Writeable for them.
 394 #[cfg_attr(test, derive(PartialEq, Debug))]
 395 pub(crate) struct HighZeroBytesDroppedVarInt<T>(pub T);
 396
 397 macro_rules! impl_writeable_primitive {
 398         ($val_type:ty, $len: expr) => {
 399                 impl Writeable for $val_type {
 400                         #[inline]
 401                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 402                                 writer.write_all(&self.to_be_bytes())
 403                         }
 404                 }
 405                 impl Writeable for HighZeroBytesDroppedVarInt<$val_type> {
 406                         #[inline]
 407                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 408                                 // Skip any full leading 0 bytes when writing (in BE):
 409                                 writer.write_all(&self.0.to_be_bytes()[(self.0.leading_zeros()/8) as usize..$len])
 410                         }
 411                 }
 412                 impl Readable for $val_type {
 413                         #[inline]
 414                         fn read<R: Read>(reader: &mut R) -> Result<$val_type, DecodeError> {
 415                                 let mut buf = [0; $len];
 416                                 reader.read_exact(&mut buf)?;
 417                                 Ok(<$val_type>::from_be_bytes(buf))
 418                         }
 419                 }
 420                 impl Readable for HighZeroBytesDroppedVarInt<$val_type> {
 421                         #[inline]
 422                         fn read<R: Read>(reader: &mut R) -> Result<HighZeroBytesDroppedVarInt<$val_type>, DecodeError> {
 423                                 // We need to accept short reads (read_len == 0) as "EOF" and handle them as simply
 424                                 // the high bytes being dropped. To do so, we start reading into the middle of buf
 425                                 // and then convert the appropriate number of bytes with extra high bytes out of
 426                                 // buf.
 427                                 let mut buf = [0; $len*2];
 428                                 let mut read_len = reader.read(&mut buf[$len..])?;
 429                                 let mut total_read_len = read_len;
 430                                 while read_len != 0 && total_read_len != $len {
 431                                         read_len = reader.read(&mut buf[($len + total_read_len)..])?;
 432                                         total_read_len += read_len;
 433                                 }
 434                                 if total_read_len == 0 || buf[$len] != 0 {
 435                                         let first_byte = $len - ($len - total_read_len);
 436                                         let mut bytes = [0; $len];
 437                                         bytes.copy_from_slice(&buf[first_byte..first_byte + $len]);
 438                                         Ok(HighZeroBytesDroppedVarInt(<$val_type>::from_be_bytes(bytes)))
 439                                 } else {
 440                                         // If the encoding had extra zero bytes, return a failure even though we know
 441                                         // what they meant (as the TLV test vectors require this)
 442                                         Err(DecodeError::InvalidValue)
 443                                 }
 444                         }
 445                 }
 446         }
 447 }
 448
 449 impl_writeable_primitive!(u64, 8);
 450 impl_writeable_primitive!(u32, 4);
 451 impl_writeable_primitive!(u16, 2);
 452
 453 impl Writeable for u8 {
 454         #[inline]
 455         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 456                 writer.write_all(&[*self])
 457         }
 458 }
 459 impl Readable for u8 {
 460         #[inline]
 461         fn read<R: Read>(reader: &mut R) -> Result<u8, DecodeError> {
 462                 let mut buf = [0; 1];
 463                 reader.read_exact(&mut buf)?;
 464                 Ok(buf[0])
 465         }
 466 }
 467
 468 impl Writeable for bool {
 469         #[inline]
 470         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 471                 writer.write_all(&[if *self {1} else {0}])
 472         }
 473 }
 474 impl Readable for bool {
 475         #[inline]
 476         fn read<R: Read>(reader: &mut R) -> Result<bool, DecodeError> {
 477                 let mut buf = [0; 1];
 478                 reader.read_exact(&mut buf)?;
 479                 if buf[0] != 0 && buf[0] != 1 {
 480                         return Err(DecodeError::InvalidValue);
 481                 }
 482                 Ok(buf[0] == 1)
 483         }
 484 }
 485
 486 // u8 arrays
 487 macro_rules! impl_array {
 488         ( $size:expr ) => (
 489                 impl Writeable for [u8; $size]
 490                 {
 491                         #[inline]
 492                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 493                                 w.write_all(self)
 494                         }
 495                 }
 496
 497                 impl Readable for [u8; $size]
 498                 {
 499                         #[inline]
 500                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 501                                 let mut buf = [0u8; $size];
 502                                 r.read_exact(&mut buf)?;
 503                                 Ok(buf)
 504                         }
 505                 }
 506         );
 507 }
 508
 509 impl_array!(3); // for rgb
 510 impl_array!(4); // for IPv4
 511 impl_array!(12); // for OnionV2
 512 impl_array!(16); // for IPv6
 513 impl_array!(32); // for channel id & hmac
 514 impl_array!(PUBLIC_KEY_SIZE); // for PublicKey
 515 impl_array!(COMPACT_SIGNATURE_SIZE); // for Signature
 516 impl_array!(1300); // for OnionPacket.hop_data
 517
 518 impl Writeable for [u16; 8] {
 519         #[inline]
 520         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 521                 for v in self.iter() {
 522                         w.write_all(&v.to_be_bytes())?
 523                 }
 524                 Ok(())
 525         }
 526 }
 527
 528 impl Readable for [u16; 8] {
 529         #[inline]
 530         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 531                 let mut buf = [0u8; 16];
 532                 r.read_exact(&mut buf)?;
 533                 let mut res = [0u16; 8];
 534                 for (idx, v) in res.iter_mut().enumerate() {
 535                         *v = (buf[idx] as u16) << 8 | (buf[idx + 1] as u16)
 536                 }
 537                 Ok(res)
 538         }
 539 }
 540
 541 // HashMap
 542 impl<K, V> Writeable for HashMap<K, V>
 543         where K: Writeable + Eq + Hash,
 544               V: Writeable
 545 {
 546         #[inline]
 547         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 548         (self.len() as u16).write(w)?;
 549                 for (key, value) in self.iter() {
 550                         key.write(w)?;
 551                         value.write(w)?;
 552                 }
 553                 Ok(())
 554         }
 555 }
 556
 557 impl<K, V> Readable for HashMap<K, V>
 558         where K: Readable + Eq + Hash,
 559               V: MaybeReadable
 560 {
 561         #[inline]
 562         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 563                 let len: u16 = Readable::read(r)?;
 564                 let mut ret = HashMap::with_capacity(len as usize);
 565                 for _ in 0..len {
 566                         let k = K::read(r)?;
 567                         let v_opt = V::read(r)?;
 568                         if let Some(v) = v_opt {
 569                                 if ret.insert(k, v).is_some() {
 570                                         return Err(DecodeError::InvalidValue);
 571                                 }
 572                         }
 573                 }
 574                 Ok(ret)
 575         }
 576 }
 577
 578 // HashSet
 579 impl<T> Writeable for HashSet<T>
 580 where T: Writeable + Eq + Hash
 581 {
 582         #[inline]
 583         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 584                 (self.len() as u16).write(w)?;
 585                 for item in self.iter() {
 586                         item.write(w)?;
 587                 }
 588                 Ok(())
 589         }
 590 }
 591
 592 impl<T> Readable for HashSet<T>
 593 where T: Readable + Eq + Hash
 594 {
 595         #[inline]
 596         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 597                 let len: u16 = Readable::read(r)?;
 598                 let mut ret = HashSet::with_capacity(len as usize);
 599                 for _ in 0..len {
 600                         if !ret.insert(T::read(r)?) {
 601                                 return Err(DecodeError::InvalidValue)
 602                         }
 603                 }
 604                 Ok(ret)
 605         }
 606 }
 607
 608 // Vectors
 609 impl Writeable for Vec<u8> {
 610         #[inline]
 611         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 612                 (self.len() as u16).write(w)?;
 613                 w.write_all(&self)
 614         }
 615 }
 616
 617 impl Readable for Vec<u8> {
 618         #[inline]
 619         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 620                 let len: u16 = Readable::read(r)?;
 621                 let mut ret = Vec::with_capacity(len as usize);
 622                 ret.resize(len as usize, 0);
 623                 r.read_exact(&mut ret)?;
 624                 Ok(ret)
 625         }
 626 }
 627 impl Writeable for Vec<Signature> {
 628         #[inline]
 629         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 630                 (self.len() as u16).write(w)?;
 631                 for e in self.iter() {
 632                         e.write(w)?;
 633                 }
 634                 Ok(())
 635         }
 636 }
 637
 638 impl Readable for Vec<Signature> {
 639         #[inline]
 640         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 641                 let len: u16 = Readable::read(r)?;
 642                 let byte_size = (len as usize)
 643                                 .checked_mul(COMPACT_SIGNATURE_SIZE)
 644                                 .ok_or(DecodeError::BadLengthDescriptor)?;
 645                 if byte_size > MAX_BUF_SIZE {
 646                         return Err(DecodeError::BadLengthDescriptor);
 647                 }
 648                 let mut ret = Vec::with_capacity(len as usize);
 649                 for _ in 0..len { ret.push(Readable::read(r)?); }
 650                 Ok(ret)
 651         }
 652 }
 653
 654 impl Writeable for Script {
 655         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 656                 (self.len() as u16).write(w)?;
 657                 w.write_all(self.as_bytes())
 658         }
 659 }
 660
 661 impl Readable for Script {
 662         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 663                 let len = <u16 as Readable>::read(r)? as usize;
 664                 let mut buf = vec![0; len];
 665                 r.read_exact(&mut buf)?;
 666                 Ok(Script::from(buf))
 667         }
 668 }
 669
 670 impl Writeable for PublicKey {
 671         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 672                 self.serialize().write(w)
 673         }
 674         #[inline]
 675         fn serialized_length(&self) -> usize {
 676                 PUBLIC_KEY_SIZE
 677         }
 678 }
 679
 680 impl Readable for PublicKey {
 681         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 682                 let buf: [u8; PUBLIC_KEY_SIZE] = Readable::read(r)?;
 683                 match PublicKey::from_slice(&buf) {
 684                         Ok(key) => Ok(key),
 685                         Err(_) => return Err(DecodeError::InvalidValue),
 686                 }
 687         }
 688 }
 689
 690 impl Writeable for SecretKey {
 691         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 692                 let mut ser = [0; SECRET_KEY_SIZE];
 693                 ser.copy_from_slice(&self[..]);
 694                 ser.write(w)
 695         }
 696         #[inline]
 697         fn serialized_length(&self) -> usize {
 698                 SECRET_KEY_SIZE
 699         }
 700 }
 701
 702 impl Readable for SecretKey {
 703         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 704                 let buf: [u8; SECRET_KEY_SIZE] = Readable::read(r)?;
 705                 match SecretKey::from_slice(&buf) {
 706                         Ok(key) => Ok(key),
 707                         Err(_) => return Err(DecodeError::InvalidValue),
 708                 }
 709         }
 710 }
 711
 712 impl Writeable for Sha256dHash {
 713         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 714                 w.write_all(&self[..])
 715         }
 716 }
 717
 718 impl Readable for Sha256dHash {
 719         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 720                 use bitcoin::hashes::Hash;
 721
 722                 let buf: [u8; 32] = Readable::read(r)?;
 723                 Ok(Sha256dHash::from_slice(&buf[..]).unwrap())
 724         }
 725 }
 726
 727 impl Writeable for Signature {
 728         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 729                 self.serialize_compact().write(w)
 730         }
 731         #[inline]
 732         fn serialized_length(&self) -> usize {
 733                 COMPACT_SIGNATURE_SIZE
 734         }
 735 }
 736
 737 impl Readable for Signature {
 738         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 739                 let buf: [u8; COMPACT_SIGNATURE_SIZE] = Readable::read(r)?;
 740                 match Signature::from_compact(&buf) {
 741                         Ok(sig) => Ok(sig),
 742                         Err(_) => return Err(DecodeError::InvalidValue),
 743                 }
 744         }
 745 }
 746
 747 impl Writeable for PaymentPreimage {
 748         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 749                 self.0.write(w)
 750         }
 751 }
 752
 753 impl Readable for PaymentPreimage {
 754         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 755                 let buf: [u8; 32] = Readable::read(r)?;
 756                 Ok(PaymentPreimage(buf))
 757         }
 758 }
 759
 760 impl Writeable for PaymentHash {
 761         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 762                 self.0.write(w)
 763         }
 764 }
 765
 766 impl Readable for PaymentHash {
 767         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 768                 let buf: [u8; 32] = Readable::read(r)?;
 769                 Ok(PaymentHash(buf))
 770         }
 771 }
 772
 773 impl Writeable for PaymentSecret {
 774         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 775                 self.0.write(w)
 776         }
 777 }
 778
 779 impl Readable for PaymentSecret {
 780         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 781                 let buf: [u8; 32] = Readable::read(r)?;
 782                 Ok(PaymentSecret(buf))
 783         }
 784 }
 785
 786 impl<T: Writeable> Writeable for Box<T> {
 787         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 788                 T::write(&**self, w)
 789         }
 790 }
 791
 792 impl<T: Readable> Readable for Box<T> {
 793         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 794                 Ok(Box::new(Readable::read(r)?))
 795         }
 796 }
 797
 798 impl<T: Writeable> Writeable for Option<T> {
 799         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 800                 match *self {
 801                         None => 0u8.write(w)?,
 802                         Some(ref data) => {
 803                                 BigSize(data.serialized_length() as u64 + 1).write(w)?;
 804                                 data.write(w)?;
 805                         }
 806                 }
 807                 Ok(())
 808         }
 809 }
 810
 811 impl<T: Readable> Readable for Option<T>
 812 {
 813         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 814                 let len: BigSize = Readable::read(r)?;
 815                 match len.0 {
 816                         0 => Ok(None),
 817                         len => {
 818                                 let mut reader = FixedLengthReader::new(r, len - 1);
 819                                 Ok(Some(Readable::read(&mut reader)?))
 820                         }
 821                 }
 822         }
 823 }
 824
 825 impl Writeable for Txid {
 826         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 827                 w.write_all(&self[..])
 828         }
 829 }
 830
 831 impl Readable for Txid {
 832         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 833                 use bitcoin::hashes::Hash;
 834
 835                 let buf: [u8; 32] = Readable::read(r)?;
 836                 Ok(Txid::from_slice(&buf[..]).unwrap())
 837         }
 838 }
 839
 840 impl Writeable for BlockHash {
 841         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 842                 w.write_all(&self[..])
 843         }
 844 }
 845
 846 impl Readable for BlockHash {
 847         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 848                 use bitcoin::hashes::Hash;
 849
 850                 let buf: [u8; 32] = Readable::read(r)?;
 851                 Ok(BlockHash::from_slice(&buf[..]).unwrap())
 852         }
 853 }
 854
 855 impl Writeable for OutPoint {
 856         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 857                 self.txid.write(w)?;
 858                 self.vout.write(w)?;
 859                 Ok(())
 860         }
 861 }
 862
 863 impl Readable for OutPoint {
 864         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 865                 let txid = Readable::read(r)?;
 866                 let vout = Readable::read(r)?;
 867                 Ok(OutPoint {
 868                         txid,
 869                         vout,
 870                 })
 871         }
 872 }
 873
 874 macro_rules! impl_consensus_ser {
 875         ($bitcoin_type: ty) => {
 876                 impl Writeable for $bitcoin_type {
 877                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 878                                 match self.consensus_encode(WriterWriteAdaptor(writer)) {
 879                                         Ok(_) => Ok(()),
 880                                         Err(e) => Err(e),
 881                                 }
 882                         }
 883                 }
 884
 885                 impl Readable for $bitcoin_type {
 886                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 887                                 match consensus::encode::Decodable::consensus_decode(r) {
 888                                         Ok(t) => Ok(t),
 889                                         Err(consensus::encode::Error::Io(ref e)) if e.kind() == io::ErrorKind::UnexpectedEof => Err(DecodeError::ShortRead),
 890                                         Err(consensus::encode::Error::Io(e)) => Err(DecodeError::Io(e.kind())),
 891                                         Err(_) => Err(DecodeError::InvalidValue),
 892                                 }
 893                         }
 894                 }
 895         }
 896 }
 897 impl_consensus_ser!(Transaction);
 898 impl_consensus_ser!(TxOut);
 899
 900 impl<T: Readable> Readable for Mutex<T> {
 901         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 902                 let t: T = Readable::read(r)?;
 903                 Ok(Mutex::new(t))
 904         }
 905 }
 906 impl<T: Writeable> Writeable for Mutex<T> {
 907         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 908                 self.lock().unwrap().write(w)
 909         }
 910 }
 911
 912 impl<A: Readable, B: Readable> Readable for (A, B) {
 913         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 914                 let a: A = Readable::read(r)?;
 915                 let b: B = Readable::read(r)?;
 916                 Ok((a, b))
 917         }
 918 }
 919 impl<A: Writeable, B: Writeable> Writeable for (A, B) {
 920         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 921                 self.0.write(w)?;
 922                 self.1.write(w)
 923         }
 924 }
 925
 926 impl<A: Readable, B: Readable, C: Readable> Readable for (A, B, C) {
 927         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 928                 let a: A = Readable::read(r)?;
 929                 let b: B = Readable::read(r)?;
 930                 let c: C = Readable::read(r)?;
 931                 Ok((a, b, c))
 932         }
 933 }
 934 impl<A: Writeable, B: Writeable, C: Writeable> Writeable for (A, B, C) {
 935         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 936                 self.0.write(w)?;
 937                 self.1.write(w)?;
 938                 self.2.write(w)
 939         }
 940 }
 941
 942 impl Writeable for () {
 943         fn write<W: Writer>(&self, _: &mut W) -> Result<(), io::Error> {
 944                 Ok(())
 945         }
 946 }
 947 impl Readable for () {
 948         fn read<R: Read>(_r: &mut R) -> Result<Self, DecodeError> {
 949                 Ok(())
 950         }
 951 }
 952
 953 impl Writeable for String {
 954         #[inline]
 955         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 956                 (self.len() as u16).write(w)?;
 957                 w.write_all(self.as_bytes())
 958         }
 959 }
 960 impl Readable for String {
 961         #[inline]
 962         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 963                 let v: Vec<u8> = Readable::read(r)?;
 964                 let ret = String::from_utf8(v).map_err(|_| DecodeError::InvalidValue)?;
 965                 Ok(ret)
 966         }
 967 }
 968
 969 /// Represents a hostname for serialization purposes.
 970 /// Only the character set and length will be validated.
 971 /// The character set consists of ASCII alphanumeric characters, hyphens, and periods.
 972 /// Its length is guaranteed to be representable by a single byte.
 973 /// This serialization is used by BOLT 7 hostnames.
 974 #[derive(Clone, Debug, PartialEq)]
 975 pub struct Hostname(String);
 976 impl Hostname {
 977         /// Returns the length of the hostname.
 978         pub fn len(&self) -> u8 {
 979                 (&self.0).len() as u8
 980         }
 981 }
 982 impl Deref for Hostname {
 983         type Target = String;
 984
 985         fn deref(&self) -> &Self::Target {
 986                 &self.0
 987         }
 988 }
 989 impl From<Hostname> for String {
 990         fn from(hostname: Hostname) -> Self {
 991                 hostname.0
 992         }
 993 }
 994 impl TryFrom<Vec<u8>> for Hostname {
 995         type Error = ();
 996
 997         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
 998                 if let Ok(s) = String::from_utf8(bytes) {
 999                         Hostname::try_from(s)
1000                 } else {
1001                         Err(())
1002                 }
1003         }
1004 }
1005 impl TryFrom<String> for Hostname {
1006         type Error = ();
1007
1008         fn try_from(s: String) -> Result<Self, Self::Error> {
1009                 if s.len() <= 255 && s.chars().all(|c|
1010                         c.is_ascii_alphanumeric() ||
1011                         c == '.' ||
1012                         c == '-'
1013                 ) {
1014                         Ok(Hostname(s))
1015                 } else {
1016                         Err(())
1017                 }
1018         }
1019 }
1020 impl Writeable for Hostname {
1021         #[inline]
1022         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1023                 self.len().write(w)?;
1024                 w.write_all(self.as_bytes())
1025         }
1026 }
1027 impl Readable for Hostname {
1028         #[inline]
1029         fn read<R: Read>(r: &mut R) -> Result<Hostname, DecodeError> {
1030                 let len: u8 = Readable::read(r)?;
1031                 let mut vec = Vec::with_capacity(len.into());
1032                 vec.resize(len.into(), 0);
1033                 r.read_exact(&mut vec)?;
1034                 Hostname::try_from(vec).map_err(|_| DecodeError::InvalidValue)
1035         }
1036 }
1037
1038 impl Writeable for Duration {
1039         #[inline]
1040         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1041                 self.as_secs().write(w)?;
1042                 self.subsec_nanos().write(w)
1043         }
1044 }
1045 impl Readable for Duration {
1046         #[inline]
1047         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1048                 let secs = Readable::read(r)?;
1049                 let nanos = Readable::read(r)?;
1050                 Ok(Duration::new(secs, nanos))
1051         }
1052 }
1053
1054 #[cfg(test)]
1055 mod tests {
1056         use core::convert::TryFrom;
1057         use util::ser::{Readable, Hostname, Writeable};
1058
1059         #[test]
1060         fn hostname_conversion() {
1061                 assert_eq!(Hostname::try_from(String::from("a-test.com")).unwrap().as_str(), "a-test.com");
1062
1063                 assert!(Hostname::try_from(String::from("\"")).is_err());
1064                 assert!(Hostname::try_from(String::from("$")).is_err());
1065                 assert!(Hostname::try_from(String::from("⚡")).is_err());
1066                 let mut large_vec = Vec::with_capacity(256);
1067                 large_vec.resize(256, b'A');
1068                 assert!(Hostname::try_from(String::from_utf8(large_vec).unwrap()).is_err());
1069         }
1070
1071         #[test]
1072         fn hostname_serialization() {
1073                 let hostname = Hostname::try_from(String::from("test")).unwrap();
1074                 let mut buf: Vec<u8> = Vec::new();
1075                 hostname.write(&mut buf).unwrap();
1076                 assert_eq!(Hostname::read(&mut buf.as_slice()).unwrap().as_str(), "test");
1077         }
1078 }