_ 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::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 higher-level rust-lightning types implement allowing them to be read in
 223 /// from a Read given some additional set of arguments which is required to deserialize.
 224 ///
 225 /// (C-not exported) as we only export serialization to/from byte arrays instead
 226 pub trait ReadableArgs<P>
 227         where Self: Sized
 228 {
 229         /// Reads a Self in from the given Read
 230         fn read<R: Read>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 231 }
 232
 233 /// A std::io::Read that also provides the total bytes available to read.
 234 pub(crate) trait LengthRead: Read {
 235         /// The total number of bytes available to read.
 236         fn total_bytes(&self) -> u64;
 237 }
 238
 239 /// A trait that various higher-level rust-lightning types implement allowing them to be read in
 240 /// from a Read given some additional set of arguments which is required to deserialize, requiring
 241 /// the implementer to provide the total length of the read.
 242 pub(crate) trait LengthReadableArgs<P> where Self: Sized
 243 {
 244         /// Reads a Self in from the given LengthRead
 245         fn read<R: LengthRead>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 246 }
 247
 248 /// A trait that various higher-level rust-lightning types implement allowing them to be read in
 249 /// from a Read, requiring the implementer to provide the total length of the read.
 250 pub(crate) trait LengthReadable where Self: Sized
 251 {
 252         /// Reads a Self in from the given LengthRead
 253         fn read<R: LengthRead>(reader: &mut R) -> Result<Self, DecodeError>;
 254 }
 255
 256 /// A trait that various rust-lightning types implement allowing them to (maybe) be read in from a Read
 257 ///
 258 /// (C-not exported) as we only export serialization to/from byte arrays instead
 259 pub trait MaybeReadable
 260         where Self: Sized
 261 {
 262         /// Reads a Self in from the given Read
 263         fn read<R: Read>(reader: &mut R) -> Result<Option<Self>, DecodeError>;
 264 }
 265
 266 impl<T: Readable> MaybeReadable for T {
 267         #[inline]
 268         fn read<R: Read>(reader: &mut R) -> Result<Option<T>, DecodeError> {
 269                 Ok(Some(Readable::read(reader)?))
 270         }
 271 }
 272
 273 pub(crate) struct OptionDeserWrapper<T: Readable>(pub Option<T>);
 274 impl<T: Readable> Readable for OptionDeserWrapper<T> {
 275         #[inline]
 276         fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
 277                 Ok(Self(Some(Readable::read(reader)?)))
 278         }
 279 }
 280 /// When handling default_values, we want to map the default-value T directly
 281 /// to a OptionDeserWrapper<T> in a way that works for `field: T = t;` as
 282 /// well. Thus, we assume `Into<T> for T` does nothing and use that.
 283 impl<T: Readable> From<T> for OptionDeserWrapper<T> {
 284         fn from(t: T) -> OptionDeserWrapper<T> { OptionDeserWrapper(Some(t)) }
 285 }
 286
 287 pub(crate) struct U48(pub u64);
 288 impl Writeable for U48 {
 289         #[inline]
 290         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 291                 writer.write_all(&be48_to_array(self.0))
 292         }
 293 }
 294 impl Readable for U48 {
 295         #[inline]
 296         fn read<R: Read>(reader: &mut R) -> Result<U48, DecodeError> {
 297                 let mut buf = [0; 6];
 298                 reader.read_exact(&mut buf)?;
 299                 Ok(U48(slice_to_be48(&buf)))
 300         }
 301 }
 302
 303 /// Lightning TLV uses a custom variable-length integer called BigSize. It is similar to Bitcoin's
 304 /// variable-length integers except that it is serialized in big-endian instead of little-endian.
 305 ///
 306 /// Like Bitcoin's variable-length integer, it exhibits ambiguity in that certain values can be
 307 /// encoded in several different ways, which we must check for at deserialization-time. Thus, if
 308 /// you're looking for an example of a variable-length integer to use for your own project, move
 309 /// along, this is a rather poor design.
 310 pub struct BigSize(pub u64);
 311 impl Writeable for BigSize {
 312         #[inline]
 313         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 314                 match self.0 {
 315                         0...0xFC => {
 316                                 (self.0 as u8).write(writer)
 317                         },
 318                         0xFD...0xFFFF => {
 319                                 0xFDu8.write(writer)?;
 320                                 (self.0 as u16).write(writer)
 321                         },
 322                         0x10000...0xFFFFFFFF => {
 323                                 0xFEu8.write(writer)?;
 324                                 (self.0 as u32).write(writer)
 325                         },
 326                         _ => {
 327                                 0xFFu8.write(writer)?;
 328                                 (self.0 as u64).write(writer)
 329                         },
 330                 }
 331         }
 332 }
 333 impl Readable for BigSize {
 334         #[inline]
 335         fn read<R: Read>(reader: &mut R) -> Result<BigSize, DecodeError> {
 336                 let n: u8 = Readable::read(reader)?;
 337                 match n {
 338                         0xFF => {
 339                                 let x: u64 = Readable::read(reader)?;
 340                                 if x < 0x100000000 {
 341                                         Err(DecodeError::InvalidValue)
 342                                 } else {
 343                                         Ok(BigSize(x))
 344                                 }
 345                         }
 346                         0xFE => {
 347                                 let x: u32 = Readable::read(reader)?;
 348                                 if x < 0x10000 {
 349                                         Err(DecodeError::InvalidValue)
 350                                 } else {
 351                                         Ok(BigSize(x as u64))
 352                                 }
 353                         }
 354                         0xFD => {
 355                                 let x: u16 = Readable::read(reader)?;
 356                                 if x < 0xFD {
 357                                         Err(DecodeError::InvalidValue)
 358                                 } else {
 359                                         Ok(BigSize(x as u64))
 360                                 }
 361                         }
 362                         n => Ok(BigSize(n as u64))
 363                 }
 364         }
 365 }
 366
 367 /// In TLV we occasionally send fields which only consist of, or potentially end with, a
 368 /// variable-length integer which is simply truncated by skipping high zero bytes. This type
 369 /// encapsulates such integers implementing Readable/Writeable for them.
 370 #[cfg_attr(test, derive(PartialEq, Eq, 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, ISO 4712 code
 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 ChainHash {
 888         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 889                 w.write_all(self.as_bytes())
 890         }
 891 }
 892
 893 impl Readable for ChainHash {
 894         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 895                 let buf: [u8; 32] = Readable::read(r)?;
 896                 Ok(ChainHash::from(&buf[..]))
 897         }
 898 }
 899
 900 impl Writeable for OutPoint {
 901         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 902                 self.txid.write(w)?;
 903                 self.vout.write(w)?;
 904                 Ok(())
 905         }
 906 }
 907
 908 impl Readable for OutPoint {
 909         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 910                 let txid = Readable::read(r)?;
 911                 let vout = Readable::read(r)?;
 912                 Ok(OutPoint {
 913                         txid,
 914                         vout,
 915                 })
 916         }
 917 }
 918
 919 macro_rules! impl_consensus_ser {
 920         ($bitcoin_type: ty) => {
 921                 impl Writeable for $bitcoin_type {
 922                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 923                                 match self.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 924                                         Ok(_) => Ok(()),
 925                                         Err(e) => Err(e),
 926                                 }
 927                         }
 928                 }
 929
 930                 impl Readable for $bitcoin_type {
 931                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 932                                 match consensus::encode::Decodable::consensus_decode(r) {
 933                                         Ok(t) => Ok(t),
 934                                         Err(consensus::encode::Error::Io(ref e)) if e.kind() == io::ErrorKind::UnexpectedEof => Err(DecodeError::ShortRead),
 935                                         Err(consensus::encode::Error::Io(e)) => Err(DecodeError::Io(e.kind())),
 936                                         Err(_) => Err(DecodeError::InvalidValue),
 937                                 }
 938                         }
 939                 }
 940         }
 941 }
 942 impl_consensus_ser!(Transaction);
 943 impl_consensus_ser!(TxOut);
 944
 945 impl<T: Readable> Readable for Mutex<T> {
 946         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 947                 let t: T = Readable::read(r)?;
 948                 Ok(Mutex::new(t))
 949         }
 950 }
 951 impl<T: Writeable> Writeable for Mutex<T> {
 952         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 953                 self.lock().unwrap().write(w)
 954         }
 955 }
 956
 957 impl<A: Readable, B: Readable> Readable for (A, B) {
 958         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 959                 let a: A = Readable::read(r)?;
 960                 let b: B = Readable::read(r)?;
 961                 Ok((a, b))
 962         }
 963 }
 964 impl<A: Writeable, B: Writeable> Writeable for (A, B) {
 965         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 966                 self.0.write(w)?;
 967                 self.1.write(w)
 968         }
 969 }
 970
 971 impl<A: Readable, B: Readable, C: Readable> Readable for (A, B, C) {
 972         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 973                 let a: A = Readable::read(r)?;
 974                 let b: B = Readable::read(r)?;
 975                 let c: C = Readable::read(r)?;
 976                 Ok((a, b, c))
 977         }
 978 }
 979 impl<A: Writeable, B: Writeable, C: Writeable> Writeable for (A, B, C) {
 980         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 981                 self.0.write(w)?;
 982                 self.1.write(w)?;
 983                 self.2.write(w)
 984         }
 985 }
 986
 987 impl Writeable for () {
 988         fn write<W: Writer>(&self, _: &mut W) -> Result<(), io::Error> {
 989                 Ok(())
 990         }
 991 }
 992 impl Readable for () {
 993         fn read<R: Read>(_r: &mut R) -> Result<Self, DecodeError> {
 994                 Ok(())
 995         }
 996 }
 997
 998 impl Writeable for String {
 999         #[inline]
1000         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1001                 (self.len() as u16).write(w)?;
1002                 w.write_all(self.as_bytes())
1003         }
1004 }
1005 impl Readable for String {
1006         #[inline]
1007         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1008                 let v: Vec<u8> = Readable::read(r)?;
1009                 let ret = String::from_utf8(v).map_err(|_| DecodeError::InvalidValue)?;
1010                 Ok(ret)
1011         }
1012 }
1013
1014 /// Represents a hostname for serialization purposes.
1015 /// Only the character set and length will be validated.
1016 /// The character set consists of ASCII alphanumeric characters, hyphens, and periods.
1017 /// Its length is guaranteed to be representable by a single byte.
1018 /// This serialization is used by BOLT 7 hostnames.
1019 #[derive(Clone, Debug, PartialEq, Eq)]
1020 pub struct Hostname(String);
1021 impl Hostname {
1022         /// Returns the length of the hostname.
1023         pub fn len(&self) -> u8 {
1024                 (&self.0).len() as u8
1025         }
1026 }
1027 impl Deref for Hostname {
1028         type Target = String;
1029
1030         fn deref(&self) -> &Self::Target {
1031                 &self.0
1032         }
1033 }
1034 impl From<Hostname> for String {
1035         fn from(hostname: Hostname) -> Self {
1036                 hostname.0
1037         }
1038 }
1039 impl TryFrom<Vec<u8>> for Hostname {
1040         type Error = ();
1041
1042         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1043                 if let Ok(s) = String::from_utf8(bytes) {
1044                         Hostname::try_from(s)
1045                 } else {
1046                         Err(())
1047                 }
1048         }
1049 }
1050 impl TryFrom<String> for Hostname {
1051         type Error = ();
1052
1053         fn try_from(s: String) -> Result<Self, Self::Error> {
1054                 if s.len() <= 255 && s.chars().all(|c|
1055                         c.is_ascii_alphanumeric() ||
1056                         c == '.' ||
1057                         c == '-'
1058                 ) {
1059                         Ok(Hostname(s))
1060                 } else {
1061                         Err(())
1062                 }
1063         }
1064 }
1065 impl Writeable for Hostname {
1066         #[inline]
1067         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1068                 self.len().write(w)?;
1069                 w.write_all(self.as_bytes())
1070         }
1071 }
1072 impl Readable for Hostname {
1073         #[inline]
1074         fn read<R: Read>(r: &mut R) -> Result<Hostname, DecodeError> {
1075                 let len: u8 = Readable::read(r)?;
1076                 let mut vec = Vec::with_capacity(len.into());
1077                 vec.resize(len.into(), 0);
1078                 r.read_exact(&mut vec)?;
1079                 Hostname::try_from(vec).map_err(|_| DecodeError::InvalidValue)
1080         }
1081 }
1082
1083 impl Writeable for Duration {
1084         #[inline]
1085         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1086                 self.as_secs().write(w)?;
1087                 self.subsec_nanos().write(w)
1088         }
1089 }
1090 impl Readable for Duration {
1091         #[inline]
1092         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1093                 let secs = Readable::read(r)?;
1094                 let nanos = Readable::read(r)?;
1095                 Ok(Duration::new(secs, nanos))
1096         }
1097 }
1098
1099 #[cfg(test)]
1100 mod tests {
1101         use core::convert::TryFrom;
1102         use crate::util::ser::{Readable, Hostname, Writeable};
1103
1104         #[test]
1105         fn hostname_conversion() {
1106                 assert_eq!(Hostname::try_from(String::from("a-test.com")).unwrap().as_str(), "a-test.com");
1107
1108                 assert!(Hostname::try_from(String::from("\"")).is_err());
1109                 assert!(Hostname::try_from(String::from("$")).is_err());
1110                 assert!(Hostname::try_from(String::from("⚡")).is_err());
1111                 let mut large_vec = Vec::with_capacity(256);
1112                 large_vec.resize(256, b'A');
1113                 assert!(Hostname::try_from(String::from_utf8(large_vec).unwrap()).is_err());
1114         }
1115
1116         #[test]
1117         fn hostname_serialization() {
1118                 let hostname = Hostname::try_from(String::from("test")).unwrap();
1119                 let mut buf: Vec<u8> = Vec::new();
1120                 hostname.write(&mut buf).unwrap();
1121                 assert_eq!(Hostname::read(&mut buf.as_slice()).unwrap().as_str(), "test");
1122         }
1123 }