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