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