git.bitcoin.ninja 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, Seek, 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::constants::ChainHash;
  26 use bitcoin::blockdata::script::Script;
  27 use bitcoin::blockdata::transaction::{OutPoint, Transaction, TxOut};
  28 use bitcoin::consensus;
  29 use bitcoin::consensus::Encodable;
  30 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
  31 use bitcoin::hash_types::{Txid, BlockHash};
  32 use core::marker::Sized;
  33 use core::time::Duration;
  34 use crate::ln::msgs::DecodeError;
  35 use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
  36
  37 use crate::util::byte_utils::{be48_to_array, slice_to_be48};
  38
  39 /// serialization buffer size
  40 pub const MAX_BUF_SIZE: usize = 64 * 1024;
  41
  42 /// A simplified version of std::io::Write that exists largely for backwards compatibility.
  43 /// An impl is provided for any type that also impls std::io::Write.
  44 ///
  45 /// (C-not exported) as we only export serialization to/from byte arrays instead
  46 pub trait Writer {
  47         /// Writes the given buf out. See std::io::Write::write_all for more
  48         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error>;
  49 }
  50
  51 impl<W: Write> Writer for W {
  52         #[inline]
  53         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  54                 <Self as io::Write>::write_all(self, buf)
  55         }
  56 }
  57
  58 pub(crate) struct WriterWriteAdaptor<'a, W: Writer + 'a>(pub &'a mut W);
  59 impl<'a, W: Writer + 'a> Write for WriterWriteAdaptor<'a, W> {
  60         #[inline]
  61         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  62                 self.0.write_all(buf)
  63         }
  64         #[inline]
  65         fn write(&mut self, buf: &[u8]) -> Result<usize, io::Error> {
  66                 self.0.write_all(buf)?;
  67                 Ok(buf.len())
  68         }
  69         #[inline]
  70         fn flush(&mut self) -> Result<(), io::Error> {
  71                 Ok(())
  72         }
  73 }
  74
  75 pub(crate) struct VecWriter(pub Vec<u8>);
  76 impl Writer for VecWriter {
  77         #[inline]
  78         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  79                 self.0.extend_from_slice(buf);
  80                 Ok(())
  81         }
  82 }
  83
  84 /// Writer that only tracks the amount of data written - useful if you need to calculate the length
  85 /// of some data when serialized but don't yet need the full data.
  86 pub(crate) struct LengthCalculatingWriter(pub usize);
  87 impl Writer for LengthCalculatingWriter {
  88         #[inline]
  89         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  90                 self.0 += buf.len();
  91                 Ok(())
  92         }
  93 }
  94
  95 /// Essentially std::io::Take but a bit simpler and with a method to walk the underlying stream
  96 /// forward to ensure we always consume exactly the fixed length specified.
  97 pub(crate) struct FixedLengthReader<R: Read> {
  98         read: R,
  99         bytes_read: u64,
 100         total_bytes: u64,
 101 }
 102 impl<R: Read> FixedLengthReader<R> {
 103         pub fn new(read: R, total_bytes: u64) -> Self {
 104                 Self { read, bytes_read: 0, total_bytes }
 105         }
 106
 107         #[inline]
 108         pub fn bytes_remain(&mut self) -> bool {
 109                 self.bytes_read != self.total_bytes
 110         }
 111
 112         #[inline]
 113         pub fn eat_remaining(&mut self) -> Result<(), DecodeError> {
 114                 copy(self, &mut sink()).unwrap();
 115                 if self.bytes_read != self.total_bytes {
 116                         Err(DecodeError::ShortRead)
 117                 } else {
 118                         Ok(())
 119                 }
 120         }
 121 }
 122 impl<R: Read> Read for FixedLengthReader<R> {
 123         #[inline]
 124         fn read(&mut self, dest: &mut [u8]) -> Result<usize, io::Error> {
 125                 if self.total_bytes == self.bytes_read {
 126                         Ok(0)
 127                 } else {
 128                         let read_len = cmp::min(dest.len() as u64, self.total_bytes - self.bytes_read);
 129                         match self.read.read(&mut dest[0..(read_len as usize)]) {
 130                                 Ok(v) => {
 131                                         self.bytes_read += v as u64;
 132                                         Ok(v)
 133                                 },
 134                                 Err(e) => Err(e),
 135                         }
 136                 }
 137         }
 138 }
 139
 140 impl<R: Read> LengthRead for FixedLengthReader<R> {
 141         #[inline]
 142         fn total_bytes(&self) -> u64 {
 143                 self.total_bytes
 144         }
 145 }
 146
 147 /// A Read which tracks whether any bytes have been read at all. This allows us to distinguish
 148 /// between "EOF reached before we started" and "EOF reached mid-read".
 149 pub(crate) struct ReadTrackingReader<R: Read> {
 150         read: R,
 151         pub have_read: bool,
 152 }
 153 impl<R: Read> ReadTrackingReader<R> {
 154         pub fn new(read: R) -> Self {
 155                 Self { read, have_read: false }
 156         }
 157 }
 158 impl<R: Read> Read for ReadTrackingReader<R> {
 159         #[inline]
 160         fn read(&mut self, dest: &mut [u8]) -> Result<usize, io::Error> {
 161                 match self.read.read(dest) {
 162                         Ok(0) => Ok(0),
 163                         Ok(len) => {
 164                                 self.have_read = true;
 165                                 Ok(len)
 166                         },
 167                         Err(e) => Err(e),
 168                 }
 169         }
 170 }
 171
 172 /// A trait that various rust-lightning types implement allowing them to be written out to a Writer
 173 ///
 174 /// (C-not exported) as we only export serialization to/from byte arrays instead
 175 pub trait Writeable {
 176         /// Writes self out to the given Writer
 177         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error>;
 178
 179         /// Writes self out to a Vec<u8>
 180         fn encode(&self) -> Vec<u8> {
 181                 let mut msg = VecWriter(Vec::new());
 182                 self.write(&mut msg).unwrap();
 183                 msg.0
 184         }
 185
 186         /// Writes self out to a Vec<u8>
 187         #[cfg(test)]
 188         fn encode_with_len(&self) -> Vec<u8> {
 189                 let mut msg = VecWriter(Vec::new());
 190                 0u16.write(&mut msg).unwrap();
 191                 self.write(&mut msg).unwrap();
 192                 let len = msg.0.len();
 193                 msg.0[..2].copy_from_slice(&(len as u16 - 2).to_be_bytes());
 194                 msg.0
 195         }
 196
 197         /// Gets the length of this object after it has been serialized. This can be overridden to
 198         /// optimize cases where we prepend an object with its length.
 199         // Note that LLVM optimizes this away in most cases! Check that it isn't before you override!
 200         #[inline]
 201         fn serialized_length(&self) -> usize {
 202                 let mut len_calc = LengthCalculatingWriter(0);
 203                 self.write(&mut len_calc).expect("No in-memory data may fail to serialize");
 204                 len_calc.0
 205         }
 206 }
 207
 208 impl<'a, T: Writeable> Writeable for &'a T {
 209         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { (*self).write(writer) }
 210 }
 211
 212 /// A trait that various rust-lightning types implement allowing them to be read in from a Read
 213 ///
 214 /// (C-not exported) as we only export serialization to/from byte arrays instead
 215 pub trait Readable
 216         where Self: Sized
 217 {
 218         /// Reads a Self in from the given Read
 219         fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError>;
 220 }
 221
 222 /// A trait that various rust-lightning types implement allowing them to be read in from a
 223 /// `Read + Seek`.
 224 pub(crate) trait SeekReadable where Self: Sized {
 225         /// Reads a Self in from the given Read
 226         fn read<R: Read + Seek>(reader: &mut R) -> Result<Self, DecodeError>;
 227 }
 228
 229 /// A trait that various higher-level rust-lightning types implement allowing them to be read in
 230 /// from a Read given some additional set of arguments which is required to deserialize.
 231 ///
 232 /// (C-not exported) as we only export serialization to/from byte arrays instead
 233 pub trait ReadableArgs<P>
 234         where Self: Sized
 235 {
 236         /// Reads a Self in from the given Read
 237         fn read<R: Read>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 238 }
 239
 240 /// A std::io::Read that also provides the total bytes available to read.
 241 pub(crate) trait LengthRead: Read {
 242         /// The total number of bytes available to read.
 243         fn total_bytes(&self) -> u64;
 244 }
 245
 246 /// A trait that various higher-level rust-lightning types implement allowing them to be read in
 247 /// from a Read given some additional set of arguments which is required to deserialize, requiring
 248 /// the implementer to provide the total length of the read.
 249 pub(crate) trait LengthReadableArgs<P> where Self: Sized
 250 {
 251         /// Reads a Self in from the given LengthRead
 252         fn read<R: LengthRead>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 253 }
 254
 255 /// A trait that various higher-level rust-lightning types implement allowing them to be read in
 256 /// from a Read, requiring the implementer to provide the total length of the read.
 257 pub(crate) trait LengthReadable where Self: Sized
 258 {
 259         /// Reads a Self in from the given LengthRead
 260         fn read<R: LengthRead>(reader: &mut R) -> Result<Self, DecodeError>;
 261 }
 262
 263 /// A trait that various rust-lightning types implement allowing them to (maybe) be read in from a Read
 264 ///
 265 /// (C-not exported) as we only export serialization to/from byte arrays instead
 266 pub trait MaybeReadable
 267         where Self: Sized
 268 {
 269         /// Reads a Self in from the given Read
 270         fn read<R: Read>(reader: &mut R) -> Result<Option<Self>, DecodeError>;
 271 }
 272
 273 impl<T: Readable> MaybeReadable for T {
 274         #[inline]
 275         fn read<R: Read>(reader: &mut R) -> Result<Option<T>, DecodeError> {
 276                 Ok(Some(Readable::read(reader)?))
 277         }
 278 }
 279
 280 pub(crate) struct OptionDeserWrapper<T: Readable>(pub Option<T>);
 281 impl<T: Readable> Readable for OptionDeserWrapper<T> {
 282         #[inline]
 283         fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
 284                 Ok(Self(Some(Readable::read(reader)?)))
 285         }
 286 }
 287 /// When handling default_values, we want to map the default-value T directly
 288 /// to a OptionDeserWrapper<T> in a way that works for `field: T = t;` as
 289 /// well. Thus, we assume `Into<T> for T` does nothing and use that.
 290 impl<T: Readable> From<T> for OptionDeserWrapper<T> {
 291         fn from(t: T) -> OptionDeserWrapper<T> { OptionDeserWrapper(Some(t)) }
 292 }
 293
 294 pub(crate) struct U48(pub u64);
 295 impl Writeable for U48 {
 296         #[inline]
 297         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 298                 writer.write_all(&be48_to_array(self.0))
 299         }
 300 }
 301 impl Readable for U48 {
 302         #[inline]
 303         fn read<R: Read>(reader: &mut R) -> Result<U48, DecodeError> {
 304                 let mut buf = [0; 6];
 305                 reader.read_exact(&mut buf)?;
 306                 Ok(U48(slice_to_be48(&buf)))
 307         }
 308 }
 309
 310 /// Lightning TLV uses a custom variable-length integer called BigSize. It is similar to Bitcoin's
 311 /// variable-length integers except that it is serialized in big-endian instead of little-endian.
 312 ///
 313 /// Like Bitcoin's variable-length integer, it exhibits ambiguity in that certain values can be
 314 /// encoded in several different ways, which we must check for at deserialization-time. Thus, if
 315 /// you're looking for an example of a variable-length integer to use for your own project, move
 316 /// along, this is a rather poor design.
 317 pub struct BigSize(pub u64);
 318 impl Writeable for BigSize {
 319         #[inline]
 320         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 321                 match self.0 {
 322                         0...0xFC => {
 323                                 (self.0 as u8).write(writer)
 324                         },
 325                         0xFD...0xFFFF => {
 326                                 0xFDu8.write(writer)?;
 327                                 (self.0 as u16).write(writer)
 328                         },
 329                         0x10000...0xFFFFFFFF => {
 330                                 0xFEu8.write(writer)?;
 331                                 (self.0 as u32).write(writer)
 332                         },
 333                         _ => {
 334                                 0xFFu8.write(writer)?;
 335                                 (self.0 as u64).write(writer)
 336                         },
 337                 }
 338         }
 339 }
 340 impl Readable for BigSize {
 341         #[inline]
 342         fn read<R: Read>(reader: &mut R) -> Result<BigSize, DecodeError> {
 343                 let n: u8 = Readable::read(reader)?;
 344                 match n {
 345                         0xFF => {
 346                                 let x: u64 = Readable::read(reader)?;
 347                                 if x < 0x100000000 {
 348                                         Err(DecodeError::InvalidValue)
 349                                 } else {
 350                                         Ok(BigSize(x))
 351                                 }
 352                         }
 353                         0xFE => {
 354                                 let x: u32 = Readable::read(reader)?;
 355                                 if x < 0x10000 {
 356                                         Err(DecodeError::InvalidValue)
 357                                 } else {
 358                                         Ok(BigSize(x as u64))
 359                                 }
 360                         }
 361                         0xFD => {
 362                                 let x: u16 = Readable::read(reader)?;
 363                                 if x < 0xFD {
 364                                         Err(DecodeError::InvalidValue)
 365                                 } else {
 366                                         Ok(BigSize(x as u64))
 367                                 }
 368                         }
 369                         n => Ok(BigSize(n as u64))
 370                 }
 371         }
 372 }
 373
 374 /// In TLV we occasionally send fields which only consist of, or potentially end with, a
 375 /// variable-length integer which is simply truncated by skipping high zero bytes. This type
 376 /// encapsulates such integers implementing Readable/Writeable for them.
 377 #[cfg_attr(test, derive(PartialEq, Eq, Debug))]
 378 pub(crate) struct HighZeroBytesDroppedBigSize<T>(pub T);
 379
 380 macro_rules! impl_writeable_primitive {
 381         ($val_type:ty, $len: expr) => {
 382                 impl Writeable for $val_type {
 383                         #[inline]
 384                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 385                                 writer.write_all(&self.to_be_bytes())
 386                         }
 387                 }
 388                 impl Writeable for HighZeroBytesDroppedBigSize<$val_type> {
 389                         #[inline]
 390                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 391                                 // Skip any full leading 0 bytes when writing (in BE):
 392                                 writer.write_all(&self.0.to_be_bytes()[(self.0.leading_zeros()/8) as usize..$len])
 393                         }
 394                 }
 395                 impl Readable for $val_type {
 396                         #[inline]
 397                         fn read<R: Read>(reader: &mut R) -> Result<$val_type, DecodeError> {
 398                                 let mut buf = [0; $len];
 399                                 reader.read_exact(&mut buf)?;
 400                                 Ok(<$val_type>::from_be_bytes(buf))
 401                         }
 402                 }
 403                 impl Readable for HighZeroBytesDroppedBigSize<$val_type> {
 404                         #[inline]
 405                         fn read<R: Read>(reader: &mut R) -> Result<HighZeroBytesDroppedBigSize<$val_type>, DecodeError> {
 406                                 // We need to accept short reads (read_len == 0) as "EOF" and handle them as simply
 407                                 // the high bytes being dropped. To do so, we start reading into the middle of buf
 408                                 // and then convert the appropriate number of bytes with extra high bytes out of
 409                                 // buf.
 410                                 let mut buf = [0; $len*2];
 411                                 let mut read_len = reader.read(&mut buf[$len..])?;
 412                                 let mut total_read_len = read_len;
 413                                 while read_len != 0 && total_read_len != $len {
 414                                         read_len = reader.read(&mut buf[($len + total_read_len)..])?;
 415                                         total_read_len += read_len;
 416                                 }
 417                                 if total_read_len == 0 || buf[$len] != 0 {
 418                                         let first_byte = $len - ($len - total_read_len);
 419                                         let mut bytes = [0; $len];
 420                                         bytes.copy_from_slice(&buf[first_byte..first_byte + $len]);
 421                                         Ok(HighZeroBytesDroppedBigSize(<$val_type>::from_be_bytes(bytes)))
 422                                 } else {
 423                                         // If the encoding had extra zero bytes, return a failure even though we know
 424                                         // what they meant (as the TLV test vectors require this)
 425                                         Err(DecodeError::InvalidValue)
 426                                 }
 427                         }
 428                 }
 429                 impl From<$val_type> for HighZeroBytesDroppedBigSize<$val_type> {
 430                         fn from(val: $val_type) -> Self { Self(val) }
 431                 }
 432         }
 433 }
 434
 435 impl_writeable_primitive!(u64, 8);
 436 impl_writeable_primitive!(u32, 4);
 437 impl_writeable_primitive!(u16, 2);
 438
 439 impl Writeable for u8 {
 440         #[inline]
 441         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 442                 writer.write_all(&[*self])
 443         }
 444 }
 445 impl Readable for u8 {
 446         #[inline]
 447         fn read<R: Read>(reader: &mut R) -> Result<u8, DecodeError> {
 448                 let mut buf = [0; 1];
 449                 reader.read_exact(&mut buf)?;
 450                 Ok(buf[0])
 451         }
 452 }
 453
 454 impl Writeable for bool {
 455         #[inline]
 456         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 457                 writer.write_all(&[if *self {1} else {0}])
 458         }
 459 }
 460 impl Readable for bool {
 461         #[inline]
 462         fn read<R: Read>(reader: &mut R) -> Result<bool, DecodeError> {
 463                 let mut buf = [0; 1];
 464                 reader.read_exact(&mut buf)?;
 465                 if buf[0] != 0 && buf[0] != 1 {
 466                         return Err(DecodeError::InvalidValue);
 467                 }
 468                 Ok(buf[0] == 1)
 469         }
 470 }
 471
 472 // u8 arrays
 473 macro_rules! impl_array {
 474         ( $size:expr ) => (
 475                 impl Writeable for [u8; $size]
 476                 {
 477                         #[inline]
 478                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 479                                 w.write_all(self)
 480                         }
 481                 }
 482
 483                 impl Readable for [u8; $size]
 484                 {
 485                         #[inline]
 486                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 487                                 let mut buf = [0u8; $size];
 488                                 r.read_exact(&mut buf)?;
 489                                 Ok(buf)
 490                         }
 491                 }
 492         );
 493 }
 494
 495 impl_array!(3); // for rgb, ISO 4712 code
 496 impl_array!(4); // for IPv4
 497 impl_array!(12); // for OnionV2
 498 impl_array!(16); // for IPv6
 499 impl_array!(32); // for channel id & hmac
 500 impl_array!(PUBLIC_KEY_SIZE); // for PublicKey
 501 impl_array!(COMPACT_SIGNATURE_SIZE); // for Signature
 502 impl_array!(1300); // for OnionPacket.hop_data
 503
 504 impl Writeable for [u16; 8] {
 505         #[inline]
 506         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 507                 for v in self.iter() {
 508                         w.write_all(&v.to_be_bytes())?
 509                 }
 510                 Ok(())
 511         }
 512 }
 513
 514 impl Readable for [u16; 8] {
 515         #[inline]
 516         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 517                 let mut buf = [0u8; 16];
 518                 r.read_exact(&mut buf)?;
 519                 let mut res = [0u16; 8];
 520                 for (idx, v) in res.iter_mut().enumerate() {
 521                         *v = (buf[idx] as u16) << 8 | (buf[idx + 1] as u16)
 522                 }
 523                 Ok(res)
 524         }
 525 }
 526
 527 /// For variable-length values within TLV record where the length is encoded as part of the record.
 528 /// Used to prevent encoding the length twice.
 529 pub(crate) struct WithoutLength<T>(pub T);
 530
 531 impl Writeable for WithoutLength<&String> {
 532         #[inline]
 533         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 534                 w.write_all(self.0.as_bytes())
 535         }
 536 }
 537 impl Readable for WithoutLength<String> {
 538         #[inline]
 539         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 540                 let v: WithoutLength<Vec<u8>> = Readable::read(r)?;
 541                 Ok(Self(String::from_utf8(v.0).map_err(|_| DecodeError::InvalidValue)?))
 542         }
 543 }
 544 impl<'a> From<&'a String> for WithoutLength<&'a String> {
 545         fn from(s: &'a String) -> Self { Self(s) }
 546 }
 547
 548 impl<'a, T: Writeable> Writeable for WithoutLength<&'a Vec<T>> {
 549         #[inline]
 550         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 551                 for ref v in self.0.iter() {
 552                         v.write(writer)?;
 553                 }
 554                 Ok(())
 555         }
 556 }
 557
 558 impl<T: MaybeReadable> Readable for WithoutLength<Vec<T>> {
 559         #[inline]
 560         fn read<R: Read>(mut reader: &mut R) -> Result<Self, DecodeError> {
 561                 let mut values = Vec::new();
 562                 loop {
 563                         let mut track_read = ReadTrackingReader::new(&mut reader);
 564                         match MaybeReadable::read(&mut track_read) {
 565                                 Ok(Some(v)) => { values.push(v); },
 566                                 Ok(None) => { },
 567                                 // If we failed to read any bytes at all, we reached the end of our TLV
 568                                 // stream and have simply exhausted all entries.
 569                                 Err(ref e) if e == &DecodeError::ShortRead && !track_read.have_read => break,
 570                                 Err(e) => return Err(e),
 571                         }
 572                 }
 573                 Ok(Self(values))
 574         }
 575 }
 576 impl<'a, T> From<&'a Vec<T>> for WithoutLength<&'a Vec<T>> {
 577         fn from(v: &'a Vec<T>) -> Self { Self(v) }
 578 }
 579
 580 // HashMap
 581 impl<K, V> Writeable for HashMap<K, V>
 582         where K: Writeable + Eq + Hash,
 583               V: Writeable
 584 {
 585         #[inline]
 586         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 587         (self.len() as u16).write(w)?;
 588                 for (key, value) in self.iter() {
 589                         key.write(w)?;
 590                         value.write(w)?;
 591                 }
 592                 Ok(())
 593         }
 594 }
 595
 596 impl<K, V> Readable for HashMap<K, V>
 597         where K: Readable + Eq + Hash,
 598               V: MaybeReadable
 599 {
 600         #[inline]
 601         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 602                 let len: u16 = Readable::read(r)?;
 603                 let mut ret = HashMap::with_capacity(len as usize);
 604                 for _ in 0..len {
 605                         let k = K::read(r)?;
 606                         let v_opt = V::read(r)?;
 607                         if let Some(v) = v_opt {
 608                                 if ret.insert(k, v).is_some() {
 609                                         return Err(DecodeError::InvalidValue);
 610                                 }
 611                         }
 612                 }
 613                 Ok(ret)
 614         }
 615 }
 616
 617 // HashSet
 618 impl<T> Writeable for HashSet<T>
 619 where T: Writeable + Eq + Hash
 620 {
 621         #[inline]
 622         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 623                 (self.len() as u16).write(w)?;
 624                 for item in self.iter() {
 625                         item.write(w)?;
 626                 }
 627                 Ok(())
 628         }
 629 }
 630
 631 impl<T> Readable for HashSet<T>
 632 where T: Readable + Eq + Hash
 633 {
 634         #[inline]
 635         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 636                 let len: u16 = Readable::read(r)?;
 637                 let mut ret = HashSet::with_capacity(len as usize);
 638                 for _ in 0..len {
 639                         if !ret.insert(T::read(r)?) {
 640                                 return Err(DecodeError::InvalidValue)
 641                         }
 642                 }
 643                 Ok(ret)
 644         }
 645 }
 646
 647 // Vectors
 648 impl Writeable for Vec<u8> {
 649         #[inline]
 650         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 651                 (self.len() as u16).write(w)?;
 652                 w.write_all(&self)
 653         }
 654 }
 655
 656 impl Readable for Vec<u8> {
 657         #[inline]
 658         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 659                 let len: u16 = Readable::read(r)?;
 660                 let mut ret = Vec::with_capacity(len as usize);
 661                 ret.resize(len as usize, 0);
 662                 r.read_exact(&mut ret)?;
 663                 Ok(ret)
 664         }
 665 }
 666 impl Writeable for Vec<Signature> {
 667         #[inline]
 668         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 669                 (self.len() as u16).write(w)?;
 670                 for e in self.iter() {
 671                         e.write(w)?;
 672                 }
 673                 Ok(())
 674         }
 675 }
 676
 677 impl Readable for Vec<Signature> {
 678         #[inline]
 679         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 680                 let len: u16 = Readable::read(r)?;
 681                 let byte_size = (len as usize)
 682                                 .checked_mul(COMPACT_SIGNATURE_SIZE)
 683                                 .ok_or(DecodeError::BadLengthDescriptor)?;
 684                 if byte_size > MAX_BUF_SIZE {
 685                         return Err(DecodeError::BadLengthDescriptor);
 686                 }
 687                 let mut ret = Vec::with_capacity(len as usize);
 688                 for _ in 0..len { ret.push(Readable::read(r)?); }
 689                 Ok(ret)
 690         }
 691 }
 692
 693 impl Writeable for Script {
 694         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 695                 (self.len() as u16).write(w)?;
 696                 w.write_all(self.as_bytes())
 697         }
 698 }
 699
 700 impl Readable for Script {
 701         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 702                 let len = <u16 as Readable>::read(r)? as usize;
 703                 let mut buf = vec![0; len];
 704                 r.read_exact(&mut buf)?;
 705                 Ok(Script::from(buf))
 706         }
 707 }
 708
 709 impl Writeable for PublicKey {
 710         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 711                 self.serialize().write(w)
 712         }
 713         #[inline]
 714         fn serialized_length(&self) -> usize {
 715                 PUBLIC_KEY_SIZE
 716         }
 717 }
 718
 719 impl Readable for PublicKey {
 720         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 721                 let buf: [u8; PUBLIC_KEY_SIZE] = Readable::read(r)?;
 722                 match PublicKey::from_slice(&buf) {
 723                         Ok(key) => Ok(key),
 724                         Err(_) => return Err(DecodeError::InvalidValue),
 725                 }
 726         }
 727 }
 728
 729 impl Writeable for SecretKey {
 730         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 731                 let mut ser = [0; SECRET_KEY_SIZE];
 732                 ser.copy_from_slice(&self[..]);
 733                 ser.write(w)
 734         }
 735         #[inline]
 736         fn serialized_length(&self) -> usize {
 737                 SECRET_KEY_SIZE
 738         }
 739 }
 740
 741 impl Readable for SecretKey {
 742         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 743                 let buf: [u8; SECRET_KEY_SIZE] = Readable::read(r)?;
 744                 match SecretKey::from_slice(&buf) {
 745                         Ok(key) => Ok(key),
 746                         Err(_) => return Err(DecodeError::InvalidValue),
 747                 }
 748         }
 749 }
 750
 751 impl Writeable for Sha256dHash {
 752         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 753                 w.write_all(&self[..])
 754         }
 755 }
 756
 757 impl Readable for Sha256dHash {
 758         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 759                 use bitcoin::hashes::Hash;
 760
 761                 let buf: [u8; 32] = Readable::read(r)?;
 762                 Ok(Sha256dHash::from_slice(&buf[..]).unwrap())
 763         }
 764 }
 765
 766 impl Writeable for Signature {
 767         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 768                 self.serialize_compact().write(w)
 769         }
 770         #[inline]
 771         fn serialized_length(&self) -> usize {
 772                 COMPACT_SIGNATURE_SIZE
 773         }
 774 }
 775
 776 impl Readable for Signature {
 777         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 778                 let buf: [u8; COMPACT_SIGNATURE_SIZE] = Readable::read(r)?;
 779                 match Signature::from_compact(&buf) {
 780                         Ok(sig) => Ok(sig),
 781                         Err(_) => return Err(DecodeError::InvalidValue),
 782                 }
 783         }
 784 }
 785
 786 impl Writeable for PaymentPreimage {
 787         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 788                 self.0.write(w)
 789         }
 790 }
 791
 792 impl Readable for PaymentPreimage {
 793         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 794                 let buf: [u8; 32] = Readable::read(r)?;
 795                 Ok(PaymentPreimage(buf))
 796         }
 797 }
 798
 799 impl Writeable for PaymentHash {
 800         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 801                 self.0.write(w)
 802         }
 803 }
 804
 805 impl Readable for PaymentHash {
 806         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 807                 let buf: [u8; 32] = Readable::read(r)?;
 808                 Ok(PaymentHash(buf))
 809         }
 810 }
 811
 812 impl Writeable for PaymentSecret {
 813         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 814                 self.0.write(w)
 815         }
 816 }
 817
 818 impl Readable for PaymentSecret {
 819         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 820                 let buf: [u8; 32] = Readable::read(r)?;
 821                 Ok(PaymentSecret(buf))
 822         }
 823 }
 824
 825 impl<T: Writeable> Writeable for Box<T> {
 826         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 827                 T::write(&**self, w)
 828         }
 829 }
 830
 831 impl<T: Readable> Readable for Box<T> {
 832         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 833                 Ok(Box::new(Readable::read(r)?))
 834         }
 835 }
 836
 837 impl<T: Writeable> Writeable for Option<T> {
 838         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 839                 match *self {
 840                         None => 0u8.write(w)?,
 841                         Some(ref data) => {
 842                                 BigSize(data.serialized_length() as u64 + 1).write(w)?;
 843                                 data.write(w)?;
 844                         }
 845                 }
 846                 Ok(())
 847         }
 848 }
 849
 850 impl<T: Readable> Readable for Option<T>
 851 {
 852         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 853                 let len: BigSize = Readable::read(r)?;
 854                 match len.0 {
 855                         0 => Ok(None),
 856                         len => {
 857                                 let mut reader = FixedLengthReader::new(r, len - 1);
 858                                 Ok(Some(Readable::read(&mut reader)?))
 859                         }
 860                 }
 861         }
 862 }
 863
 864 impl Writeable for Txid {
 865         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 866                 w.write_all(&self[..])
 867         }
 868 }
 869
 870 impl Readable for Txid {
 871         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 872                 use bitcoin::hashes::Hash;
 873
 874                 let buf: [u8; 32] = Readable::read(r)?;
 875                 Ok(Txid::from_slice(&buf[..]).unwrap())
 876         }
 877 }
 878
 879 impl Writeable for BlockHash {
 880         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 881                 w.write_all(&self[..])
 882         }
 883 }
 884
 885 impl Readable for BlockHash {
 886         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 887                 use bitcoin::hashes::Hash;
 888
 889                 let buf: [u8; 32] = Readable::read(r)?;
 890                 Ok(BlockHash::from_slice(&buf[..]).unwrap())
 891         }
 892 }
 893
 894 impl Writeable for ChainHash {
 895         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 896                 w.write_all(self.as_bytes())
 897         }
 898 }
 899
 900 impl Readable for ChainHash {
 901         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 902                 let buf: [u8; 32] = Readable::read(r)?;
 903                 Ok(ChainHash::from(&buf[..]))
 904         }
 905 }
 906
 907 impl Writeable for OutPoint {
 908         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 909                 self.txid.write(w)?;
 910                 self.vout.write(w)?;
 911                 Ok(())
 912         }
 913 }
 914
 915 impl Readable for OutPoint {
 916         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 917                 let txid = Readable::read(r)?;
 918                 let vout = Readable::read(r)?;
 919                 Ok(OutPoint {
 920                         txid,
 921                         vout,
 922                 })
 923         }
 924 }
 925
 926 macro_rules! impl_consensus_ser {
 927         ($bitcoin_type: ty) => {
 928                 impl Writeable for $bitcoin_type {
 929                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 930                                 match self.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 931                                         Ok(_) => Ok(()),
 932                                         Err(e) => Err(e),
 933                                 }
 934                         }
 935                 }
 936
 937                 impl Readable for $bitcoin_type {
 938                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 939                                 match consensus::encode::Decodable::consensus_decode(r) {
 940                                         Ok(t) => Ok(t),
 941                                         Err(consensus::encode::Error::Io(ref e)) if e.kind() == io::ErrorKind::UnexpectedEof => Err(DecodeError::ShortRead),
 942                                         Err(consensus::encode::Error::Io(e)) => Err(DecodeError::Io(e.kind())),
 943                                         Err(_) => Err(DecodeError::InvalidValue),
 944                                 }
 945                         }
 946                 }
 947         }
 948 }
 949 impl_consensus_ser!(Transaction);
 950 impl_consensus_ser!(TxOut);
 951
 952 impl<T: Readable> Readable for Mutex<T> {
 953         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 954                 let t: T = Readable::read(r)?;
 955                 Ok(Mutex::new(t))
 956         }
 957 }
 958 impl<T: Writeable> Writeable for Mutex<T> {
 959         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 960                 self.lock().unwrap().write(w)
 961         }
 962 }
 963
 964 impl<A: Readable, B: Readable> Readable for (A, B) {
 965         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 966                 let a: A = Readable::read(r)?;
 967                 let b: B = Readable::read(r)?;
 968                 Ok((a, b))
 969         }
 970 }
 971 impl<A: Writeable, B: Writeable> Writeable for (A, B) {
 972         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 973                 self.0.write(w)?;
 974                 self.1.write(w)
 975         }
 976 }
 977
 978 impl<A: Readable, B: Readable, C: Readable> Readable for (A, B, C) {
 979         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 980                 let a: A = Readable::read(r)?;
 981                 let b: B = Readable::read(r)?;
 982                 let c: C = Readable::read(r)?;
 983                 Ok((a, b, c))
 984         }
 985 }
 986 impl<A: Writeable, B: Writeable, C: Writeable> Writeable for (A, B, C) {
 987         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 988                 self.0.write(w)?;
 989                 self.1.write(w)?;
 990                 self.2.write(w)
 991         }
 992 }
 993
 994 impl Writeable for () {
 995         fn write<W: Writer>(&self, _: &mut W) -> Result<(), io::Error> {
 996                 Ok(())
 997         }
 998 }
 999 impl Readable for () {
1000         fn read<R: Read>(_r: &mut R) -> Result<Self, DecodeError> {
1001                 Ok(())
1002         }
1003 }
1004
1005 impl Writeable for String {
1006         #[inline]
1007         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1008                 (self.len() as u16).write(w)?;
1009                 w.write_all(self.as_bytes())
1010         }
1011 }
1012 impl Readable for String {
1013         #[inline]
1014         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1015                 let v: Vec<u8> = Readable::read(r)?;
1016                 let ret = String::from_utf8(v).map_err(|_| DecodeError::InvalidValue)?;
1017                 Ok(ret)
1018         }
1019 }
1020
1021 /// Represents a hostname for serialization purposes.
1022 /// Only the character set and length will be validated.
1023 /// The character set consists of ASCII alphanumeric characters, hyphens, and periods.
1024 /// Its length is guaranteed to be representable by a single byte.
1025 /// This serialization is used by BOLT 7 hostnames.
1026 #[derive(Clone, Debug, PartialEq, Eq)]
1027 pub struct Hostname(String);
1028 impl Hostname {
1029         /// Returns the length of the hostname.
1030         pub fn len(&self) -> u8 {
1031                 (&self.0).len() as u8
1032         }
1033 }
1034 impl Deref for Hostname {
1035         type Target = String;
1036
1037         fn deref(&self) -> &Self::Target {
1038                 &self.0
1039         }
1040 }
1041 impl From<Hostname> for String {
1042         fn from(hostname: Hostname) -> Self {
1043                 hostname.0
1044         }
1045 }
1046 impl TryFrom<Vec<u8>> for Hostname {
1047         type Error = ();
1048
1049         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1050                 if let Ok(s) = String::from_utf8(bytes) {
1051                         Hostname::try_from(s)
1052                 } else {
1053                         Err(())
1054                 }
1055         }
1056 }
1057 impl TryFrom<String> for Hostname {
1058         type Error = ();
1059
1060         fn try_from(s: String) -> Result<Self, Self::Error> {
1061                 if s.len() <= 255 && s.chars().all(|c|
1062                         c.is_ascii_alphanumeric() ||
1063                         c == '.' ||
1064                         c == '-'
1065                 ) {
1066                         Ok(Hostname(s))
1067                 } else {
1068                         Err(())
1069                 }
1070         }
1071 }
1072 impl Writeable for Hostname {
1073         #[inline]
1074         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1075                 self.len().write(w)?;
1076                 w.write_all(self.as_bytes())
1077         }
1078 }
1079 impl Readable for Hostname {
1080         #[inline]
1081         fn read<R: Read>(r: &mut R) -> Result<Hostname, DecodeError> {
1082                 let len: u8 = Readable::read(r)?;
1083                 let mut vec = Vec::with_capacity(len.into());
1084                 vec.resize(len.into(), 0);
1085                 r.read_exact(&mut vec)?;
1086                 Hostname::try_from(vec).map_err(|_| DecodeError::InvalidValue)
1087         }
1088 }
1089
1090 impl Writeable for Duration {
1091         #[inline]
1092         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1093                 self.as_secs().write(w)?;
1094                 self.subsec_nanos().write(w)
1095         }
1096 }
1097 impl Readable for Duration {
1098         #[inline]
1099         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1100                 let secs = Readable::read(r)?;
1101                 let nanos = Readable::read(r)?;
1102                 Ok(Duration::new(secs, nanos))
1103         }
1104 }
1105
1106 #[cfg(test)]
1107 mod tests {
1108         use core::convert::TryFrom;
1109         use crate::util::ser::{Readable, Hostname, Writeable};
1110
1111         #[test]
1112         fn hostname_conversion() {
1113                 assert_eq!(Hostname::try_from(String::from("a-test.com")).unwrap().as_str(), "a-test.com");
1114
1115                 assert!(Hostname::try_from(String::from("\"")).is_err());
1116                 assert!(Hostname::try_from(String::from("$")).is_err());
1117                 assert!(Hostname::try_from(String::from("⚡")).is_err());
1118                 let mut large_vec = Vec::with_capacity(256);
1119                 large_vec.resize(256, b'A');
1120                 assert!(Hostname::try_from(String::from_utf8(large_vec).unwrap()).is_err());
1121         }
1122
1123         #[test]
1124         fn hostname_serialization() {
1125                 let hostname = Hostname::try_from(String::from("test")).unwrap();
1126                 let mut buf: Vec<u8> = Vec::new();
1127                 hostname.write(&mut buf).unwrap();
1128                 assert_eq!(Hostname::read(&mut buf.as_slice()).unwrap().as_str(), "test");
1129         }
1130 }