_ 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 crate::prelude::*;
  14 use crate::io::{self, Read, Write};
  15 use crate::io_extras::{copy, sink};
  16 use core::hash::Hash;
  17 use crate::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 crate::ln::msgs::DecodeError;
  34 use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
  35
  36 use crate::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 pub(crate) struct U48(pub u64);
 287 impl Writeable for U48 {
 288         #[inline]
 289         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 290                 writer.write_all(&be48_to_array(self.0))
 291         }
 292 }
 293 impl Readable for U48 {
 294         #[inline]
 295         fn read<R: Read>(reader: &mut R) -> Result<U48, DecodeError> {
 296                 let mut buf = [0; 6];
 297                 reader.read_exact(&mut buf)?;
 298                 Ok(U48(slice_to_be48(&buf)))
 299         }
 300 }
 301
 302 /// Lightning TLV uses a custom variable-length integer called BigSize. It is similar to Bitcoin's
 303 /// variable-length integers except that it is serialized in big-endian instead of little-endian.
 304 ///
 305 /// Like Bitcoin's variable-length integer, it exhibits ambiguity in that certain values can be
 306 /// encoded in several different ways, which we must check for at deserialization-time. Thus, if
 307 /// you're looking for an example of a variable-length integer to use for your own project, move
 308 /// along, this is a rather poor design.
 309 pub struct BigSize(pub u64);
 310 impl Writeable for BigSize {
 311         #[inline]
 312         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 313                 match self.0 {
 314                         0...0xFC => {
 315                                 (self.0 as u8).write(writer)
 316                         },
 317                         0xFD...0xFFFF => {
 318                                 0xFDu8.write(writer)?;
 319                                 (self.0 as u16).write(writer)
 320                         },
 321                         0x10000...0xFFFFFFFF => {
 322                                 0xFEu8.write(writer)?;
 323                                 (self.0 as u32).write(writer)
 324                         },
 325                         _ => {
 326                                 0xFFu8.write(writer)?;
 327                                 (self.0 as u64).write(writer)
 328                         },
 329                 }
 330         }
 331 }
 332 impl Readable for BigSize {
 333         #[inline]
 334         fn read<R: Read>(reader: &mut R) -> Result<BigSize, DecodeError> {
 335                 let n: u8 = Readable::read(reader)?;
 336                 match n {
 337                         0xFF => {
 338                                 let x: u64 = Readable::read(reader)?;
 339                                 if x < 0x100000000 {
 340                                         Err(DecodeError::InvalidValue)
 341                                 } else {
 342                                         Ok(BigSize(x))
 343                                 }
 344                         }
 345                         0xFE => {
 346                                 let x: u32 = Readable::read(reader)?;
 347                                 if x < 0x10000 {
 348                                         Err(DecodeError::InvalidValue)
 349                                 } else {
 350                                         Ok(BigSize(x as u64))
 351                                 }
 352                         }
 353                         0xFD => {
 354                                 let x: u16 = Readable::read(reader)?;
 355                                 if x < 0xFD {
 356                                         Err(DecodeError::InvalidValue)
 357                                 } else {
 358                                         Ok(BigSize(x as u64))
 359                                 }
 360                         }
 361                         n => Ok(BigSize(n as u64))
 362                 }
 363         }
 364 }
 365
 366 /// In TLV we occasionally send fields which only consist of, or potentially end with, a
 367 /// variable-length integer which is simply truncated by skipping high zero bytes. This type
 368 /// encapsulates such integers implementing Readable/Writeable for them.
 369 #[cfg_attr(test, derive(PartialEq, Eq))]
 370 #[derive(Clone, Debug)]
 371 pub(crate) struct HighZeroBytesDroppedBigSize<T>(pub T);
 372
 373 macro_rules! impl_writeable_primitive {
 374         ($val_type:ty, $len: expr) => {
 375                 impl Writeable for $val_type {
 376                         #[inline]
 377                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 378                                 writer.write_all(&self.to_be_bytes())
 379                         }
 380                 }
 381                 impl Writeable for HighZeroBytesDroppedBigSize<$val_type> {
 382                         #[inline]
 383                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 384                                 // Skip any full leading 0 bytes when writing (in BE):
 385                                 writer.write_all(&self.0.to_be_bytes()[(self.0.leading_zeros()/8) as usize..$len])
 386                         }
 387                 }
 388                 impl Readable for $val_type {
 389                         #[inline]
 390                         fn read<R: Read>(reader: &mut R) -> Result<$val_type, DecodeError> {
 391                                 let mut buf = [0; $len];
 392                                 reader.read_exact(&mut buf)?;
 393                                 Ok(<$val_type>::from_be_bytes(buf))
 394                         }
 395                 }
 396                 impl Readable for HighZeroBytesDroppedBigSize<$val_type> {
 397                         #[inline]
 398                         fn read<R: Read>(reader: &mut R) -> Result<HighZeroBytesDroppedBigSize<$val_type>, DecodeError> {
 399                                 // We need to accept short reads (read_len == 0) as "EOF" and handle them as simply
 400                                 // the high bytes being dropped. To do so, we start reading into the middle of buf
 401                                 // and then convert the appropriate number of bytes with extra high bytes out of
 402                                 // buf.
 403                                 let mut buf = [0; $len*2];
 404                                 let mut read_len = reader.read(&mut buf[$len..])?;
 405                                 let mut total_read_len = read_len;
 406                                 while read_len != 0 && total_read_len != $len {
 407                                         read_len = reader.read(&mut buf[($len + total_read_len)..])?;
 408                                         total_read_len += read_len;
 409                                 }
 410                                 if total_read_len == 0 || buf[$len] != 0 {
 411                                         let first_byte = $len - ($len - total_read_len);
 412                                         let mut bytes = [0; $len];
 413                                         bytes.copy_from_slice(&buf[first_byte..first_byte + $len]);
 414                                         Ok(HighZeroBytesDroppedBigSize(<$val_type>::from_be_bytes(bytes)))
 415                                 } else {
 416                                         // If the encoding had extra zero bytes, return a failure even though we know
 417                                         // what they meant (as the TLV test vectors require this)
 418                                         Err(DecodeError::InvalidValue)
 419                                 }
 420                         }
 421                 }
 422                 impl From<$val_type> for HighZeroBytesDroppedBigSize<$val_type> {
 423                         fn from(val: $val_type) -> Self { Self(val) }
 424                 }
 425         }
 426 }
 427
 428 impl_writeable_primitive!(u64, 8);
 429 impl_writeable_primitive!(u32, 4);
 430 impl_writeable_primitive!(u16, 2);
 431
 432 impl Writeable for u8 {
 433         #[inline]
 434         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 435                 writer.write_all(&[*self])
 436         }
 437 }
 438 impl Readable for u8 {
 439         #[inline]
 440         fn read<R: Read>(reader: &mut R) -> Result<u8, DecodeError> {
 441                 let mut buf = [0; 1];
 442                 reader.read_exact(&mut buf)?;
 443                 Ok(buf[0])
 444         }
 445 }
 446
 447 impl Writeable for bool {
 448         #[inline]
 449         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 450                 writer.write_all(&[if *self {1} else {0}])
 451         }
 452 }
 453 impl Readable for bool {
 454         #[inline]
 455         fn read<R: Read>(reader: &mut R) -> Result<bool, DecodeError> {
 456                 let mut buf = [0; 1];
 457                 reader.read_exact(&mut buf)?;
 458                 if buf[0] != 0 && buf[0] != 1 {
 459                         return Err(DecodeError::InvalidValue);
 460                 }
 461                 Ok(buf[0] == 1)
 462         }
 463 }
 464
 465 // u8 arrays
 466 macro_rules! impl_array {
 467         ( $size:expr ) => (
 468                 impl Writeable for [u8; $size]
 469                 {
 470                         #[inline]
 471                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 472                                 w.write_all(self)
 473                         }
 474                 }
 475
 476                 impl Readable for [u8; $size]
 477                 {
 478                         #[inline]
 479                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 480                                 let mut buf = [0u8; $size];
 481                                 r.read_exact(&mut buf)?;
 482                                 Ok(buf)
 483                         }
 484                 }
 485         );
 486 }
 487
 488 impl_array!(3); // for rgb
 489 impl_array!(4); // for IPv4
 490 impl_array!(12); // for OnionV2
 491 impl_array!(16); // for IPv6
 492 impl_array!(32); // for channel id & hmac
 493 impl_array!(PUBLIC_KEY_SIZE); // for PublicKey
 494 impl_array!(COMPACT_SIGNATURE_SIZE); // for Signature
 495 impl_array!(1300); // for OnionPacket.hop_data
 496
 497 impl Writeable for [u16; 8] {
 498         #[inline]
 499         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 500                 for v in self.iter() {
 501                         w.write_all(&v.to_be_bytes())?
 502                 }
 503                 Ok(())
 504         }
 505 }
 506
 507 impl Readable for [u16; 8] {
 508         #[inline]
 509         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 510                 let mut buf = [0u8; 16];
 511                 r.read_exact(&mut buf)?;
 512                 let mut res = [0u16; 8];
 513                 for (idx, v) in res.iter_mut().enumerate() {
 514                         *v = (buf[idx] as u16) << 8 | (buf[idx + 1] as u16)
 515                 }
 516                 Ok(res)
 517         }
 518 }
 519
 520 /// For variable-length values within TLV record where the length is encoded as part of the record.
 521 /// Used to prevent encoding the length twice.
 522 pub(crate) struct WithoutLength<T>(pub T);
 523
 524 impl Writeable for WithoutLength<&String> {
 525         #[inline]
 526         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 527                 w.write_all(self.0.as_bytes())
 528         }
 529 }
 530 impl Readable for WithoutLength<String> {
 531         #[inline]
 532         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 533                 let v: WithoutLength<Vec<u8>> = Readable::read(r)?;
 534                 Ok(Self(String::from_utf8(v.0).map_err(|_| DecodeError::InvalidValue)?))
 535         }
 536 }
 537 impl<'a> From<&'a String> for WithoutLength<&'a String> {
 538         fn from(s: &'a String) -> Self { Self(s) }
 539 }
 540
 541 impl<'a, T: Writeable> Writeable for WithoutLength<&'a Vec<T>> {
 542         #[inline]
 543         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 544                 for ref v in self.0.iter() {
 545                         v.write(writer)?;
 546                 }
 547                 Ok(())
 548         }
 549 }
 550
 551 impl<T: MaybeReadable> Readable for WithoutLength<Vec<T>> {
 552         #[inline]
 553         fn read<R: Read>(mut reader: &mut R) -> Result<Self, DecodeError> {
 554                 let mut values = Vec::new();
 555                 loop {
 556                         let mut track_read = ReadTrackingReader::new(&mut reader);
 557                         match MaybeReadable::read(&mut track_read) {
 558                                 Ok(Some(v)) => { values.push(v); },
 559                                 Ok(None) => { },
 560                                 // If we failed to read any bytes at all, we reached the end of our TLV
 561                                 // stream and have simply exhausted all entries.
 562                                 Err(ref e) if e == &DecodeError::ShortRead && !track_read.have_read => break,
 563                                 Err(e) => return Err(e),
 564                         }
 565                 }
 566                 Ok(Self(values))
 567         }
 568 }
 569 impl<'a, T> From<&'a Vec<T>> for WithoutLength<&'a Vec<T>> {
 570         fn from(v: &'a Vec<T>) -> Self { Self(v) }
 571 }
 572
 573 // HashMap
 574 impl<K, V> Writeable for HashMap<K, V>
 575         where K: Writeable + Eq + Hash,
 576               V: Writeable
 577 {
 578         #[inline]
 579         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 580         (self.len() as u16).write(w)?;
 581                 for (key, value) in self.iter() {
 582                         key.write(w)?;
 583                         value.write(w)?;
 584                 }
 585                 Ok(())
 586         }
 587 }
 588
 589 impl<K, V> Readable for HashMap<K, V>
 590         where K: Readable + Eq + Hash,
 591               V: MaybeReadable
 592 {
 593         #[inline]
 594         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 595                 let len: u16 = Readable::read(r)?;
 596                 let mut ret = HashMap::with_capacity(len as usize);
 597                 for _ in 0..len {
 598                         let k = K::read(r)?;
 599                         let v_opt = V::read(r)?;
 600                         if let Some(v) = v_opt {
 601                                 if ret.insert(k, v).is_some() {
 602                                         return Err(DecodeError::InvalidValue);
 603                                 }
 604                         }
 605                 }
 606                 Ok(ret)
 607         }
 608 }
 609
 610 // HashSet
 611 impl<T> Writeable for HashSet<T>
 612 where T: Writeable + Eq + Hash
 613 {
 614         #[inline]
 615         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 616                 (self.len() as u16).write(w)?;
 617                 for item in self.iter() {
 618                         item.write(w)?;
 619                 }
 620                 Ok(())
 621         }
 622 }
 623
 624 impl<T> Readable for HashSet<T>
 625 where T: Readable + Eq + Hash
 626 {
 627         #[inline]
 628         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 629                 let len: u16 = Readable::read(r)?;
 630                 let mut ret = HashSet::with_capacity(len as usize);
 631                 for _ in 0..len {
 632                         if !ret.insert(T::read(r)?) {
 633                                 return Err(DecodeError::InvalidValue)
 634                         }
 635                 }
 636                 Ok(ret)
 637         }
 638 }
 639
 640 // Vectors
 641 impl Writeable for Vec<u8> {
 642         #[inline]
 643         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 644                 (self.len() as u16).write(w)?;
 645                 w.write_all(&self)
 646         }
 647 }
 648
 649 impl Readable for Vec<u8> {
 650         #[inline]
 651         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 652                 let len: u16 = Readable::read(r)?;
 653                 let mut ret = Vec::with_capacity(len as usize);
 654                 ret.resize(len as usize, 0);
 655                 r.read_exact(&mut ret)?;
 656                 Ok(ret)
 657         }
 658 }
 659 impl Writeable for Vec<Signature> {
 660         #[inline]
 661         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 662                 (self.len() as u16).write(w)?;
 663                 for e in self.iter() {
 664                         e.write(w)?;
 665                 }
 666                 Ok(())
 667         }
 668 }
 669
 670 impl Readable for Vec<Signature> {
 671         #[inline]
 672         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 673                 let len: u16 = Readable::read(r)?;
 674                 let byte_size = (len as usize)
 675                                 .checked_mul(COMPACT_SIGNATURE_SIZE)
 676                                 .ok_or(DecodeError::BadLengthDescriptor)?;
 677                 if byte_size > MAX_BUF_SIZE {
 678                         return Err(DecodeError::BadLengthDescriptor);
 679                 }
 680                 let mut ret = Vec::with_capacity(len as usize);
 681                 for _ in 0..len { ret.push(Readable::read(r)?); }
 682                 Ok(ret)
 683         }
 684 }
 685
 686 impl Writeable for Script {
 687         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 688                 (self.len() as u16).write(w)?;
 689                 w.write_all(self.as_bytes())
 690         }
 691 }
 692
 693 impl Readable for Script {
 694         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 695                 let len = <u16 as Readable>::read(r)? as usize;
 696                 let mut buf = vec![0; len];
 697                 r.read_exact(&mut buf)?;
 698                 Ok(Script::from(buf))
 699         }
 700 }
 701
 702 impl Writeable for PublicKey {
 703         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 704                 self.serialize().write(w)
 705         }
 706         #[inline]
 707         fn serialized_length(&self) -> usize {
 708                 PUBLIC_KEY_SIZE
 709         }
 710 }
 711
 712 impl Readable for PublicKey {
 713         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 714                 let buf: [u8; PUBLIC_KEY_SIZE] = Readable::read(r)?;
 715                 match PublicKey::from_slice(&buf) {
 716                         Ok(key) => Ok(key),
 717                         Err(_) => return Err(DecodeError::InvalidValue),
 718                 }
 719         }
 720 }
 721
 722 impl Writeable for SecretKey {
 723         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 724                 let mut ser = [0; SECRET_KEY_SIZE];
 725                 ser.copy_from_slice(&self[..]);
 726                 ser.write(w)
 727         }
 728         #[inline]
 729         fn serialized_length(&self) -> usize {
 730                 SECRET_KEY_SIZE
 731         }
 732 }
 733
 734 impl Readable for SecretKey {
 735         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 736                 let buf: [u8; SECRET_KEY_SIZE] = Readable::read(r)?;
 737                 match SecretKey::from_slice(&buf) {
 738                         Ok(key) => Ok(key),
 739                         Err(_) => return Err(DecodeError::InvalidValue),
 740                 }
 741         }
 742 }
 743
 744 impl Writeable for Sha256dHash {
 745         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 746                 w.write_all(&self[..])
 747         }
 748 }
 749
 750 impl Readable for Sha256dHash {
 751         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 752                 use bitcoin::hashes::Hash;
 753
 754                 let buf: [u8; 32] = Readable::read(r)?;
 755                 Ok(Sha256dHash::from_slice(&buf[..]).unwrap())
 756         }
 757 }
 758
 759 impl Writeable for Signature {
 760         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 761                 self.serialize_compact().write(w)
 762         }
 763         #[inline]
 764         fn serialized_length(&self) -> usize {
 765                 COMPACT_SIGNATURE_SIZE
 766         }
 767 }
 768
 769 impl Readable for Signature {
 770         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 771                 let buf: [u8; COMPACT_SIGNATURE_SIZE] = Readable::read(r)?;
 772                 match Signature::from_compact(&buf) {
 773                         Ok(sig) => Ok(sig),
 774                         Err(_) => return Err(DecodeError::InvalidValue),
 775                 }
 776         }
 777 }
 778
 779 impl Writeable for PaymentPreimage {
 780         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 781                 self.0.write(w)
 782         }
 783 }
 784
 785 impl Readable for PaymentPreimage {
 786         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 787                 let buf: [u8; 32] = Readable::read(r)?;
 788                 Ok(PaymentPreimage(buf))
 789         }
 790 }
 791
 792 impl Writeable for PaymentHash {
 793         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 794                 self.0.write(w)
 795         }
 796 }
 797
 798 impl Readable for PaymentHash {
 799         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 800                 let buf: [u8; 32] = Readable::read(r)?;
 801                 Ok(PaymentHash(buf))
 802         }
 803 }
 804
 805 impl Writeable for PaymentSecret {
 806         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 807                 self.0.write(w)
 808         }
 809 }
 810
 811 impl Readable for PaymentSecret {
 812         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 813                 let buf: [u8; 32] = Readable::read(r)?;
 814                 Ok(PaymentSecret(buf))
 815         }
 816 }
 817
 818 impl<T: Writeable> Writeable for Box<T> {
 819         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 820                 T::write(&**self, w)
 821         }
 822 }
 823
 824 impl<T: Readable> Readable for Box<T> {
 825         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 826                 Ok(Box::new(Readable::read(r)?))
 827         }
 828 }
 829
 830 impl<T: Writeable> Writeable for Option<T> {
 831         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 832                 match *self {
 833                         None => 0u8.write(w)?,
 834                         Some(ref data) => {
 835                                 BigSize(data.serialized_length() as u64 + 1).write(w)?;
 836                                 data.write(w)?;
 837                         }
 838                 }
 839                 Ok(())
 840         }
 841 }
 842
 843 impl<T: Readable> Readable for Option<T>
 844 {
 845         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 846                 let len: BigSize = Readable::read(r)?;
 847                 match len.0 {
 848                         0 => Ok(None),
 849                         len => {
 850                                 let mut reader = FixedLengthReader::new(r, len - 1);
 851                                 Ok(Some(Readable::read(&mut reader)?))
 852                         }
 853                 }
 854         }
 855 }
 856
 857 impl Writeable for Txid {
 858         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 859                 w.write_all(&self[..])
 860         }
 861 }
 862
 863 impl Readable for Txid {
 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(Txid::from_slice(&buf[..]).unwrap())
 869         }
 870 }
 871
 872 impl Writeable for BlockHash {
 873         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 874                 w.write_all(&self[..])
 875         }
 876 }
 877
 878 impl Readable for BlockHash {
 879         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 880                 use bitcoin::hashes::Hash;
 881
 882                 let buf: [u8; 32] = Readable::read(r)?;
 883                 Ok(BlockHash::from_slice(&buf[..]).unwrap())
 884         }
 885 }
 886
 887 impl Writeable for OutPoint {
 888         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 889                 self.txid.write(w)?;
 890                 self.vout.write(w)?;
 891                 Ok(())
 892         }
 893 }
 894
 895 impl Readable for OutPoint {
 896         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 897                 let txid = Readable::read(r)?;
 898                 let vout = Readable::read(r)?;
 899                 Ok(OutPoint {
 900                         txid,
 901                         vout,
 902                 })
 903         }
 904 }
 905
 906 macro_rules! impl_consensus_ser {
 907         ($bitcoin_type: ty) => {
 908                 impl Writeable for $bitcoin_type {
 909                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 910                                 match self.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 911                                         Ok(_) => Ok(()),
 912                                         Err(e) => Err(e),
 913                                 }
 914                         }
 915                 }
 916
 917                 impl Readable for $bitcoin_type {
 918                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 919                                 match consensus::encode::Decodable::consensus_decode(r) {
 920                                         Ok(t) => Ok(t),
 921                                         Err(consensus::encode::Error::Io(ref e)) if e.kind() == io::ErrorKind::UnexpectedEof => Err(DecodeError::ShortRead),
 922                                         Err(consensus::encode::Error::Io(e)) => Err(DecodeError::Io(e.kind())),
 923                                         Err(_) => Err(DecodeError::InvalidValue),
 924                                 }
 925                         }
 926                 }
 927         }
 928 }
 929 impl_consensus_ser!(Transaction);
 930 impl_consensus_ser!(TxOut);
 931
 932 impl<T: Readable> Readable for Mutex<T> {
 933         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 934                 let t: T = Readable::read(r)?;
 935                 Ok(Mutex::new(t))
 936         }
 937 }
 938 impl<T: Writeable> Writeable for Mutex<T> {
 939         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 940                 self.lock().unwrap().write(w)
 941         }
 942 }
 943
 944 impl<A: Readable, B: Readable> Readable for (A, B) {
 945         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 946                 let a: A = Readable::read(r)?;
 947                 let b: B = Readable::read(r)?;
 948                 Ok((a, b))
 949         }
 950 }
 951 impl<A: Writeable, B: Writeable> Writeable for (A, B) {
 952         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 953                 self.0.write(w)?;
 954                 self.1.write(w)
 955         }
 956 }
 957
 958 impl<A: Readable, B: Readable, C: Readable> Readable for (A, B, C) {
 959         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 960                 let a: A = Readable::read(r)?;
 961                 let b: B = Readable::read(r)?;
 962                 let c: C = Readable::read(r)?;
 963                 Ok((a, b, c))
 964         }
 965 }
 966 impl<A: Writeable, B: Writeable, C: Writeable> Writeable for (A, B, C) {
 967         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 968                 self.0.write(w)?;
 969                 self.1.write(w)?;
 970                 self.2.write(w)
 971         }
 972 }
 973
 974 impl Writeable for () {
 975         fn write<W: Writer>(&self, _: &mut W) -> Result<(), io::Error> {
 976                 Ok(())
 977         }
 978 }
 979 impl Readable for () {
 980         fn read<R: Read>(_r: &mut R) -> Result<Self, DecodeError> {
 981                 Ok(())
 982         }
 983 }
 984
 985 impl Writeable for String {
 986         #[inline]
 987         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 988                 (self.len() as u16).write(w)?;
 989                 w.write_all(self.as_bytes())
 990         }
 991 }
 992 impl Readable for String {
 993         #[inline]
 994         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 995                 let v: Vec<u8> = Readable::read(r)?;
 996                 let ret = String::from_utf8(v).map_err(|_| DecodeError::InvalidValue)?;
 997                 Ok(ret)
 998         }
 999 }
1000
1001 /// Represents a hostname for serialization purposes.
1002 /// Only the character set and length will be validated.
1003 /// The character set consists of ASCII alphanumeric characters, hyphens, and periods.
1004 /// Its length is guaranteed to be representable by a single byte.
1005 /// This serialization is used by BOLT 7 hostnames.
1006 #[derive(Clone, Debug, PartialEq, Eq)]
1007 pub struct Hostname(String);
1008 impl Hostname {
1009         /// Returns the length of the hostname.
1010         pub fn len(&self) -> u8 {
1011                 (&self.0).len() as u8
1012         }
1013 }
1014 impl Deref for Hostname {
1015         type Target = String;
1016
1017         fn deref(&self) -> &Self::Target {
1018                 &self.0
1019         }
1020 }
1021 impl From<Hostname> for String {
1022         fn from(hostname: Hostname) -> Self {
1023                 hostname.0
1024         }
1025 }
1026 impl TryFrom<Vec<u8>> for Hostname {
1027         type Error = ();
1028
1029         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1030                 if let Ok(s) = String::from_utf8(bytes) {
1031                         Hostname::try_from(s)
1032                 } else {
1033                         Err(())
1034                 }
1035         }
1036 }
1037 impl TryFrom<String> for Hostname {
1038         type Error = ();
1039
1040         fn try_from(s: String) -> Result<Self, Self::Error> {
1041                 if s.len() <= 255 && s.chars().all(|c|
1042                         c.is_ascii_alphanumeric() ||
1043                         c == '.' ||
1044                         c == '-'
1045                 ) {
1046                         Ok(Hostname(s))
1047                 } else {
1048                         Err(())
1049                 }
1050         }
1051 }
1052 impl Writeable for Hostname {
1053         #[inline]
1054         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1055                 self.len().write(w)?;
1056                 w.write_all(self.as_bytes())
1057         }
1058 }
1059 impl Readable for Hostname {
1060         #[inline]
1061         fn read<R: Read>(r: &mut R) -> Result<Hostname, DecodeError> {
1062                 let len: u8 = Readable::read(r)?;
1063                 let mut vec = Vec::with_capacity(len.into());
1064                 vec.resize(len.into(), 0);
1065                 r.read_exact(&mut vec)?;
1066                 Hostname::try_from(vec).map_err(|_| DecodeError::InvalidValue)
1067         }
1068 }
1069
1070 impl Writeable for Duration {
1071         #[inline]
1072         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1073                 self.as_secs().write(w)?;
1074                 self.subsec_nanos().write(w)
1075         }
1076 }
1077 impl Readable for Duration {
1078         #[inline]
1079         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1080                 let secs = Readable::read(r)?;
1081                 let nanos = Readable::read(r)?;
1082                 Ok(Duration::new(secs, nanos))
1083         }
1084 }
1085
1086 #[cfg(test)]
1087 mod tests {
1088         use core::convert::TryFrom;
1089         use crate::util::ser::{Readable, Hostname, Writeable};
1090
1091         #[test]
1092         fn hostname_conversion() {
1093                 assert_eq!(Hostname::try_from(String::from("a-test.com")).unwrap().as_str(), "a-test.com");
1094
1095                 assert!(Hostname::try_from(String::from("\"")).is_err());
1096                 assert!(Hostname::try_from(String::from("$")).is_err());
1097                 assert!(Hostname::try_from(String::from("⚡")).is_err());
1098                 let mut large_vec = Vec::with_capacity(256);
1099                 large_vec.resize(256, b'A');
1100                 assert!(Hostname::try_from(String::from_utf8(large_vec).unwrap()).is_err());
1101         }
1102
1103         #[test]
1104         fn hostname_serialization() {
1105                 let hostname = Hostname::try_from(String::from("test")).unwrap();
1106                 let mut buf: Vec<u8> = Vec::new();
1107                 hostname.write(&mut buf).unwrap();
1108                 assert_eq!(Hostname::read(&mut buf.as_slice()).unwrap().as_str(), "test");
1109         }
1110 }