_ 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, Eq, 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 impl Writeable for [u16; 8] {
 536         #[inline]
 537         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 538                 for v in self.iter() {
 539                         w.write_all(&v.to_be_bytes())?
 540                 }
 541                 Ok(())
 542         }
 543 }
 544
 545 impl Readable for [u16; 8] {
 546         #[inline]
 547         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 548                 let mut buf = [0u8; 16];
 549                 r.read_exact(&mut buf)?;
 550                 let mut res = [0u16; 8];
 551                 for (idx, v) in res.iter_mut().enumerate() {
 552                         *v = (buf[idx] as u16) << 8 | (buf[idx + 1] as u16)
 553                 }
 554                 Ok(res)
 555         }
 556 }
 557
 558 // HashMap
 559 impl<K, V> Writeable for HashMap<K, V>
 560         where K: Writeable + Eq + Hash,
 561               V: Writeable
 562 {
 563         #[inline]
 564         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 565         (self.len() as u16).write(w)?;
 566                 for (key, value) in self.iter() {
 567                         key.write(w)?;
 568                         value.write(w)?;
 569                 }
 570                 Ok(())
 571         }
 572 }
 573
 574 impl<K, V> Readable for HashMap<K, V>
 575         where K: Readable + Eq + Hash,
 576               V: MaybeReadable
 577 {
 578         #[inline]
 579         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 580                 let len: u16 = Readable::read(r)?;
 581                 let mut ret = HashMap::with_capacity(len as usize);
 582                 for _ in 0..len {
 583                         let k = K::read(r)?;
 584                         let v_opt = V::read(r)?;
 585                         if let Some(v) = v_opt {
 586                                 if ret.insert(k, v).is_some() {
 587                                         return Err(DecodeError::InvalidValue);
 588                                 }
 589                         }
 590                 }
 591                 Ok(ret)
 592         }
 593 }
 594
 595 // HashSet
 596 impl<T> Writeable for HashSet<T>
 597 where T: Writeable + Eq + Hash
 598 {
 599         #[inline]
 600         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 601                 (self.len() as u16).write(w)?;
 602                 for item in self.iter() {
 603                         item.write(w)?;
 604                 }
 605                 Ok(())
 606         }
 607 }
 608
 609 impl<T> Readable for HashSet<T>
 610 where T: Readable + Eq + Hash
 611 {
 612         #[inline]
 613         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 614                 let len: u16 = Readable::read(r)?;
 615                 let mut ret = HashSet::with_capacity(len as usize);
 616                 for _ in 0..len {
 617                         if !ret.insert(T::read(r)?) {
 618                                 return Err(DecodeError::InvalidValue)
 619                         }
 620                 }
 621                 Ok(ret)
 622         }
 623 }
 624
 625 // Vectors
 626 impl Writeable for Vec<u8> {
 627         #[inline]
 628         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 629                 (self.len() as u16).write(w)?;
 630                 w.write_all(&self)
 631         }
 632 }
 633
 634 impl Readable for Vec<u8> {
 635         #[inline]
 636         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 637                 let len: u16 = Readable::read(r)?;
 638                 let mut ret = Vec::with_capacity(len as usize);
 639                 ret.resize(len as usize, 0);
 640                 r.read_exact(&mut ret)?;
 641                 Ok(ret)
 642         }
 643 }
 644 impl Writeable for Vec<Signature> {
 645         #[inline]
 646         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 647                 (self.len() as u16).write(w)?;
 648                 for e in self.iter() {
 649                         e.write(w)?;
 650                 }
 651                 Ok(())
 652         }
 653 }
 654
 655 impl Readable for Vec<Signature> {
 656         #[inline]
 657         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 658                 let len: u16 = Readable::read(r)?;
 659                 let byte_size = (len as usize)
 660                                 .checked_mul(COMPACT_SIGNATURE_SIZE)
 661                                 .ok_or(DecodeError::BadLengthDescriptor)?;
 662                 if byte_size > MAX_BUF_SIZE {
 663                         return Err(DecodeError::BadLengthDescriptor);
 664                 }
 665                 let mut ret = Vec::with_capacity(len as usize);
 666                 for _ in 0..len { ret.push(Readable::read(r)?); }
 667                 Ok(ret)
 668         }
 669 }
 670
 671 impl Writeable for Script {
 672         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 673                 (self.len() as u16).write(w)?;
 674                 w.write_all(self.as_bytes())
 675         }
 676 }
 677
 678 impl Readable for Script {
 679         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 680                 let len = <u16 as Readable>::read(r)? as usize;
 681                 let mut buf = vec![0; len];
 682                 r.read_exact(&mut buf)?;
 683                 Ok(Script::from(buf))
 684         }
 685 }
 686
 687 impl Writeable for PublicKey {
 688         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 689                 self.serialize().write(w)
 690         }
 691         #[inline]
 692         fn serialized_length(&self) -> usize {
 693                 PUBLIC_KEY_SIZE
 694         }
 695 }
 696
 697 impl Readable for PublicKey {
 698         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 699                 let buf: [u8; PUBLIC_KEY_SIZE] = Readable::read(r)?;
 700                 match PublicKey::from_slice(&buf) {
 701                         Ok(key) => Ok(key),
 702                         Err(_) => return Err(DecodeError::InvalidValue),
 703                 }
 704         }
 705 }
 706
 707 impl Writeable for SecretKey {
 708         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 709                 let mut ser = [0; SECRET_KEY_SIZE];
 710                 ser.copy_from_slice(&self[..]);
 711                 ser.write(w)
 712         }
 713         #[inline]
 714         fn serialized_length(&self) -> usize {
 715                 SECRET_KEY_SIZE
 716         }
 717 }
 718
 719 impl Readable for SecretKey {
 720         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 721                 let buf: [u8; SECRET_KEY_SIZE] = Readable::read(r)?;
 722                 match SecretKey::from_slice(&buf) {
 723                         Ok(key) => Ok(key),
 724                         Err(_) => return Err(DecodeError::InvalidValue),
 725                 }
 726         }
 727 }
 728
 729 impl Writeable for Sha256dHash {
 730         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 731                 w.write_all(&self[..])
 732         }
 733 }
 734
 735 impl Readable for Sha256dHash {
 736         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 737                 use bitcoin::hashes::Hash;
 738
 739                 let buf: [u8; 32] = Readable::read(r)?;
 740                 Ok(Sha256dHash::from_slice(&buf[..]).unwrap())
 741         }
 742 }
 743
 744 impl Writeable for Signature {
 745         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 746                 self.serialize_compact().write(w)
 747         }
 748         #[inline]
 749         fn serialized_length(&self) -> usize {
 750                 COMPACT_SIGNATURE_SIZE
 751         }
 752 }
 753
 754 impl Readable for Signature {
 755         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 756                 let buf: [u8; COMPACT_SIGNATURE_SIZE] = Readable::read(r)?;
 757                 match Signature::from_compact(&buf) {
 758                         Ok(sig) => Ok(sig),
 759                         Err(_) => return Err(DecodeError::InvalidValue),
 760                 }
 761         }
 762 }
 763
 764 impl Writeable for PaymentPreimage {
 765         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 766                 self.0.write(w)
 767         }
 768 }
 769
 770 impl Readable for PaymentPreimage {
 771         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 772                 let buf: [u8; 32] = Readable::read(r)?;
 773                 Ok(PaymentPreimage(buf))
 774         }
 775 }
 776
 777 impl Writeable for PaymentHash {
 778         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 779                 self.0.write(w)
 780         }
 781 }
 782
 783 impl Readable for PaymentHash {
 784         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 785                 let buf: [u8; 32] = Readable::read(r)?;
 786                 Ok(PaymentHash(buf))
 787         }
 788 }
 789
 790 impl Writeable for PaymentSecret {
 791         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 792                 self.0.write(w)
 793         }
 794 }
 795
 796 impl Readable for PaymentSecret {
 797         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 798                 let buf: [u8; 32] = Readable::read(r)?;
 799                 Ok(PaymentSecret(buf))
 800         }
 801 }
 802
 803 impl<T: Writeable> Writeable for Box<T> {
 804         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 805                 T::write(&**self, w)
 806         }
 807 }
 808
 809 impl<T: Readable> Readable for Box<T> {
 810         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 811                 Ok(Box::new(Readable::read(r)?))
 812         }
 813 }
 814
 815 impl<T: Writeable> Writeable for Option<T> {
 816         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 817                 match *self {
 818                         None => 0u8.write(w)?,
 819                         Some(ref data) => {
 820                                 BigSize(data.serialized_length() as u64 + 1).write(w)?;
 821                                 data.write(w)?;
 822                         }
 823                 }
 824                 Ok(())
 825         }
 826 }
 827
 828 impl<T: Readable> Readable for Option<T>
 829 {
 830         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 831                 let len: BigSize = Readable::read(r)?;
 832                 match len.0 {
 833                         0 => Ok(None),
 834                         len => {
 835                                 let mut reader = FixedLengthReader::new(r, len - 1);
 836                                 Ok(Some(Readable::read(&mut reader)?))
 837                         }
 838                 }
 839         }
 840 }
 841
 842 impl Writeable for Txid {
 843         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 844                 w.write_all(&self[..])
 845         }
 846 }
 847
 848 impl Readable for Txid {
 849         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 850                 use bitcoin::hashes::Hash;
 851
 852                 let buf: [u8; 32] = Readable::read(r)?;
 853                 Ok(Txid::from_slice(&buf[..]).unwrap())
 854         }
 855 }
 856
 857 impl Writeable for BlockHash {
 858         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 859                 w.write_all(&self[..])
 860         }
 861 }
 862
 863 impl Readable for BlockHash {
 864         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 865                 use bitcoin::hashes::Hash;
 866
 867                 let buf: [u8; 32] = Readable::read(r)?;
 868                 Ok(BlockHash::from_slice(&buf[..]).unwrap())
 869         }
 870 }
 871
 872 impl Writeable for OutPoint {
 873         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 874                 self.txid.write(w)?;
 875                 self.vout.write(w)?;
 876                 Ok(())
 877         }
 878 }
 879
 880 impl Readable for OutPoint {
 881         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 882                 let txid = Readable::read(r)?;
 883                 let vout = Readable::read(r)?;
 884                 Ok(OutPoint {
 885                         txid,
 886                         vout,
 887                 })
 888         }
 889 }
 890
 891 macro_rules! impl_consensus_ser {
 892         ($bitcoin_type: ty) => {
 893                 impl Writeable for $bitcoin_type {
 894                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 895                                 match self.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 896                                         Ok(_) => Ok(()),
 897                                         Err(e) => Err(e),
 898                                 }
 899                         }
 900                 }
 901
 902                 impl Readable for $bitcoin_type {
 903                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 904                                 match consensus::encode::Decodable::consensus_decode(r) {
 905                                         Ok(t) => Ok(t),
 906                                         Err(consensus::encode::Error::Io(ref e)) if e.kind() == io::ErrorKind::UnexpectedEof => Err(DecodeError::ShortRead),
 907                                         Err(consensus::encode::Error::Io(e)) => Err(DecodeError::Io(e.kind())),
 908                                         Err(_) => Err(DecodeError::InvalidValue),
 909                                 }
 910                         }
 911                 }
 912         }
 913 }
 914 impl_consensus_ser!(Transaction);
 915 impl_consensus_ser!(TxOut);
 916
 917 impl<T: Readable> Readable for Mutex<T> {
 918         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 919                 let t: T = Readable::read(r)?;
 920                 Ok(Mutex::new(t))
 921         }
 922 }
 923 impl<T: Writeable> Writeable for Mutex<T> {
 924         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 925                 self.lock().unwrap().write(w)
 926         }
 927 }
 928
 929 impl<A: Readable, B: Readable> Readable for (A, B) {
 930         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 931                 let a: A = Readable::read(r)?;
 932                 let b: B = Readable::read(r)?;
 933                 Ok((a, b))
 934         }
 935 }
 936 impl<A: Writeable, B: Writeable> Writeable for (A, B) {
 937         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 938                 self.0.write(w)?;
 939                 self.1.write(w)
 940         }
 941 }
 942
 943 impl<A: Readable, B: Readable, C: Readable> Readable for (A, B, C) {
 944         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 945                 let a: A = Readable::read(r)?;
 946                 let b: B = Readable::read(r)?;
 947                 let c: C = Readable::read(r)?;
 948                 Ok((a, b, c))
 949         }
 950 }
 951 impl<A: Writeable, B: Writeable, C: Writeable> Writeable for (A, B, C) {
 952         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 953                 self.0.write(w)?;
 954                 self.1.write(w)?;
 955                 self.2.write(w)
 956         }
 957 }
 958
 959 impl Writeable for () {
 960         fn write<W: Writer>(&self, _: &mut W) -> Result<(), io::Error> {
 961                 Ok(())
 962         }
 963 }
 964 impl Readable for () {
 965         fn read<R: Read>(_r: &mut R) -> Result<Self, DecodeError> {
 966                 Ok(())
 967         }
 968 }
 969
 970 impl Writeable for String {
 971         #[inline]
 972         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 973                 (self.len() as u16).write(w)?;
 974                 w.write_all(self.as_bytes())
 975         }
 976 }
 977 impl Readable for String {
 978         #[inline]
 979         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 980                 let v: Vec<u8> = Readable::read(r)?;
 981                 let ret = String::from_utf8(v).map_err(|_| DecodeError::InvalidValue)?;
 982                 Ok(ret)
 983         }
 984 }
 985
 986 /// Represents a hostname for serialization purposes.
 987 /// Only the character set and length will be validated.
 988 /// The character set consists of ASCII alphanumeric characters, hyphens, and periods.
 989 /// Its length is guaranteed to be representable by a single byte.
 990 /// This serialization is used by BOLT 7 hostnames.
 991 #[derive(Clone, Debug, PartialEq, Eq)]
 992 pub struct Hostname(String);
 993 impl Hostname {
 994         /// Returns the length of the hostname.
 995         pub fn len(&self) -> u8 {
 996                 (&self.0).len() as u8
 997         }
 998 }
 999 impl Deref for Hostname {
1000         type Target = String;
1001
1002         fn deref(&self) -> &Self::Target {
1003                 &self.0
1004         }
1005 }
1006 impl From<Hostname> for String {
1007         fn from(hostname: Hostname) -> Self {
1008                 hostname.0
1009         }
1010 }
1011 impl TryFrom<Vec<u8>> for Hostname {
1012         type Error = ();
1013
1014         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1015                 if let Ok(s) = String::from_utf8(bytes) {
1016                         Hostname::try_from(s)
1017                 } else {
1018                         Err(())
1019                 }
1020         }
1021 }
1022 impl TryFrom<String> for Hostname {
1023         type Error = ();
1024
1025         fn try_from(s: String) -> Result<Self, Self::Error> {
1026                 if s.len() <= 255 && s.chars().all(|c|
1027                         c.is_ascii_alphanumeric() ||
1028                         c == '.' ||
1029                         c == '-'
1030                 ) {
1031                         Ok(Hostname(s))
1032                 } else {
1033                         Err(())
1034                 }
1035         }
1036 }
1037 impl Writeable for Hostname {
1038         #[inline]
1039         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1040                 self.len().write(w)?;
1041                 w.write_all(self.as_bytes())
1042         }
1043 }
1044 impl Readable for Hostname {
1045         #[inline]
1046         fn read<R: Read>(r: &mut R) -> Result<Hostname, DecodeError> {
1047                 let len: u8 = Readable::read(r)?;
1048                 let mut vec = Vec::with_capacity(len.into());
1049                 vec.resize(len.into(), 0);
1050                 r.read_exact(&mut vec)?;
1051                 Hostname::try_from(vec).map_err(|_| DecodeError::InvalidValue)
1052         }
1053 }
1054
1055 impl Writeable for Duration {
1056         #[inline]
1057         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1058                 self.as_secs().write(w)?;
1059                 self.subsec_nanos().write(w)
1060         }
1061 }
1062 impl Readable for Duration {
1063         #[inline]
1064         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1065                 let secs = Readable::read(r)?;
1066                 let nanos = Readable::read(r)?;
1067                 Ok(Duration::new(secs, nanos))
1068         }
1069 }
1070
1071 #[cfg(test)]
1072 mod tests {
1073         use core::convert::TryFrom;
1074         use util::ser::{Readable, Hostname, Writeable};
1075
1076         #[test]
1077         fn hostname_conversion() {
1078                 assert_eq!(Hostname::try_from(String::from("a-test.com")).unwrap().as_str(), "a-test.com");
1079
1080                 assert!(Hostname::try_from(String::from("\"")).is_err());
1081                 assert!(Hostname::try_from(String::from("$")).is_err());
1082                 assert!(Hostname::try_from(String::from("⚡")).is_err());
1083                 let mut large_vec = Vec::with_capacity(256);
1084                 large_vec.resize(256, b'A');
1085                 assert!(Hostname::try_from(String::from_utf8(large_vec).unwrap()).is_err());
1086         }
1087
1088         #[test]
1089         fn hostname_serialization() {
1090                 let hostname = Hostname::try_from(String::from("test")).unwrap();
1091                 let mut buf: Vec<u8> = Vec::new();
1092                 hostname.write(&mut buf).unwrap();
1093                 assert_eq!(Hostname::read(&mut buf.as_slice()).unwrap().as_str(), "test");
1094         }
1095 }