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