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 [`ChannelManager`]s and [`ChannelMonitor`]s.
  12 //!
  13 //! [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
  14 //! [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
  15
  16 use crate::prelude::*;
  17 use crate::io::{self, Read, Seek, Write};
  18 use crate::io_extras::{copy, sink};
  19 use core::hash::Hash;
  20 use crate::sync::{Mutex, RwLock};
  21 use core::cmp;
  22 use core::convert::TryFrom;
  23 use core::ops::Deref;
  24
  25 use alloc::collections::BTreeMap;
  26
  27 use bitcoin::secp256k1::{PublicKey, SecretKey};
  28 use bitcoin::secp256k1::constants::{PUBLIC_KEY_SIZE, SECRET_KEY_SIZE, COMPACT_SIGNATURE_SIZE, SCHNORR_SIGNATURE_SIZE};
  29 use bitcoin::secp256k1::ecdsa;
  30 use bitcoin::secp256k1::schnorr;
  31 use bitcoin::blockdata::constants::ChainHash;
  32 use bitcoin::blockdata::script::{self, Script};
  33 use bitcoin::blockdata::transaction::{OutPoint, Transaction, TxOut};
  34 use bitcoin::{consensus, Witness};
  35 use bitcoin::consensus::Encodable;
  36 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
  37 use bitcoin::hash_types::{Txid, BlockHash};
  38 use core::marker::Sized;
  39 use core::time::Duration;
  40 use crate::chain::ClaimId;
  41 use crate::ln::msgs::DecodeError;
  42 #[cfg(taproot)]
  43 use crate::ln::msgs::PartialSignatureWithNonce;
  44 use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
  45
  46 use crate::util::byte_utils::{be48_to_array, slice_to_be48};
  47 use crate::util::string::UntrustedString;
  48
  49 /// serialization buffer size
  50 pub const MAX_BUF_SIZE: usize = 64 * 1024;
  51
  52 /// A simplified version of [`std::io::Write`] that exists largely for backwards compatibility.
  53 /// An impl is provided for any type that also impls [`std::io::Write`].
  54 ///
  55 /// This is not exported to bindings users as we only export serialization to/from byte arrays instead
  56 pub trait Writer {
  57         /// Writes the given buf out. See std::io::Write::write_all for more
  58         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error>;
  59 }
  60
  61 impl<W: Write> Writer for W {
  62         #[inline]
  63         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  64                 <Self as io::Write>::write_all(self, buf)
  65         }
  66 }
  67
  68 pub(crate) struct WriterWriteAdaptor<'a, W: Writer + 'a>(pub &'a mut W);
  69 impl<'a, W: Writer + 'a> Write for WriterWriteAdaptor<'a, W> {
  70         #[inline]
  71         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  72                 self.0.write_all(buf)
  73         }
  74         #[inline]
  75         fn write(&mut self, buf: &[u8]) -> Result<usize, io::Error> {
  76                 self.0.write_all(buf)?;
  77                 Ok(buf.len())
  78         }
  79         #[inline]
  80         fn flush(&mut self) -> Result<(), io::Error> {
  81                 Ok(())
  82         }
  83 }
  84
  85 pub(crate) struct VecWriter(pub Vec<u8>);
  86 impl Writer for VecWriter {
  87         #[inline]
  88         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  89                 self.0.extend_from_slice(buf);
  90                 Ok(())
  91         }
  92 }
  93
  94 /// Writer that only tracks the amount of data written - useful if you need to calculate the length
  95 /// of some data when serialized but don't yet need the full data.
  96 ///
  97 /// This is not exported to bindings users as manual TLV building is not currently supported in bindings
  98 pub struct LengthCalculatingWriter(pub usize);
  99 impl Writer for LengthCalculatingWriter {
 100         #[inline]
 101         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
 102                 self.0 += buf.len();
 103                 Ok(())
 104         }
 105 }
 106
 107 /// Essentially [`std::io::Take`] but a bit simpler and with a method to walk the underlying stream
 108 /// forward to ensure we always consume exactly the fixed length specified.
 109 ///
 110 /// This is not exported to bindings users as manual TLV building is not currently supported in bindings
 111 pub struct FixedLengthReader<R: Read> {
 112         read: R,
 113         bytes_read: u64,
 114         total_bytes: u64,
 115 }
 116 impl<R: Read> FixedLengthReader<R> {
 117         /// Returns a new [`FixedLengthReader`].
 118         pub fn new(read: R, total_bytes: u64) -> Self {
 119                 Self { read, bytes_read: 0, total_bytes }
 120         }
 121
 122         /// Returns whether some bytes are remaining or not.
 123         #[inline]
 124         pub fn bytes_remain(&mut self) -> bool {
 125                 self.bytes_read != self.total_bytes
 126         }
 127
 128         /// Consumes the remaining bytes.
 129         #[inline]
 130         pub fn eat_remaining(&mut self) -> Result<(), DecodeError> {
 131                 copy(self, &mut sink()).unwrap();
 132                 if self.bytes_read != self.total_bytes {
 133                         Err(DecodeError::ShortRead)
 134                 } else {
 135                         Ok(())
 136                 }
 137         }
 138 }
 139 impl<R: Read> Read for FixedLengthReader<R> {
 140         #[inline]
 141         fn read(&mut self, dest: &mut [u8]) -> Result<usize, io::Error> {
 142                 if self.total_bytes == self.bytes_read {
 143                         Ok(0)
 144                 } else {
 145                         let read_len = cmp::min(dest.len() as u64, self.total_bytes - self.bytes_read);
 146                         match self.read.read(&mut dest[0..(read_len as usize)]) {
 147                                 Ok(v) => {
 148                                         self.bytes_read += v as u64;
 149                                         Ok(v)
 150                                 },
 151                                 Err(e) => Err(e),
 152                         }
 153                 }
 154         }
 155 }
 156
 157 impl<R: Read> LengthRead for FixedLengthReader<R> {
 158         #[inline]
 159         fn total_bytes(&self) -> u64 {
 160                 self.total_bytes
 161         }
 162 }
 163
 164 /// A [`Read`] implementation which tracks whether any bytes have been read at all. This allows us to distinguish
 165 /// between "EOF reached before we started" and "EOF reached mid-read".
 166 ///
 167 /// This is not exported to bindings users as manual TLV building is not currently supported in bindings
 168 pub struct ReadTrackingReader<R: Read> {
 169         read: R,
 170         /// Returns whether we have read from this reader or not yet.
 171         pub have_read: bool,
 172 }
 173 impl<R: Read> ReadTrackingReader<R> {
 174         /// Returns a new [`ReadTrackingReader`].
 175         pub fn new(read: R) -> Self {
 176                 Self { read, have_read: false }
 177         }
 178 }
 179 impl<R: Read> Read for ReadTrackingReader<R> {
 180         #[inline]
 181         fn read(&mut self, dest: &mut [u8]) -> Result<usize, io::Error> {
 182                 match self.read.read(dest) {
 183                         Ok(0) => Ok(0),
 184                         Ok(len) => {
 185                                 self.have_read = true;
 186                                 Ok(len)
 187                         },
 188                         Err(e) => Err(e),
 189                 }
 190         }
 191 }
 192
 193 /// A trait that various LDK types implement allowing them to be written out to a [`Writer`].
 194 ///
 195 /// This is not exported to bindings users as we only export serialization to/from byte arrays instead
 196 pub trait Writeable {
 197         /// Writes `self` out to the given [`Writer`].
 198         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error>;
 199
 200         /// Writes `self` out to a `Vec<u8>`.
 201         fn encode(&self) -> Vec<u8> {
 202                 let len = self.serialized_length();
 203                 let mut msg = VecWriter(Vec::with_capacity(len));
 204                 self.write(&mut msg).unwrap();
 205                 // Note that objects with interior mutability may change size between when we called
 206                 // serialized_length and when we called write. That's okay, but shouldn't happen during
 207                 // testing as most of our tests are not threaded.
 208                 #[cfg(test)]
 209                 debug_assert_eq!(len, msg.0.len());
 210                 msg.0
 211         }
 212
 213         /// Writes `self` out to a `Vec<u8>`.
 214         #[cfg(test)]
 215         fn encode_with_len(&self) -> Vec<u8> {
 216                 let mut msg = VecWriter(Vec::new());
 217                 0u16.write(&mut msg).unwrap();
 218                 self.write(&mut msg).unwrap();
 219                 let len = msg.0.len();
 220                 debug_assert_eq!(len - 2, self.serialized_length());
 221                 msg.0[..2].copy_from_slice(&(len as u16 - 2).to_be_bytes());
 222                 msg.0
 223         }
 224
 225         /// Gets the length of this object after it has been serialized. This can be overridden to
 226         /// optimize cases where we prepend an object with its length.
 227         // Note that LLVM optimizes this away in most cases! Check that it isn't before you override!
 228         #[inline]
 229         fn serialized_length(&self) -> usize {
 230                 let mut len_calc = LengthCalculatingWriter(0);
 231                 self.write(&mut len_calc).expect("No in-memory data may fail to serialize");
 232                 len_calc.0
 233         }
 234 }
 235
 236 impl<'a, T: Writeable> Writeable for &'a T {
 237         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { (*self).write(writer) }
 238 }
 239
 240 /// A trait that various LDK types implement allowing them to be read in from a [`Read`].
 241 ///
 242 /// This is not exported to bindings users as we only export serialization to/from byte arrays instead
 243 pub trait Readable
 244         where Self: Sized
 245 {
 246         /// Reads a `Self` in from the given [`Read`].
 247         fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError>;
 248 }
 249
 250 /// A trait that various LDK types implement allowing them to be read in from a
 251 /// [`Read`]` + `[`Seek`].
 252 pub(crate) trait SeekReadable where Self: Sized {
 253         /// Reads a `Self` in from the given [`Read`].
 254         fn read<R: Read + Seek>(reader: &mut R) -> Result<Self, DecodeError>;
 255 }
 256
 257 /// A trait that various higher-level LDK types implement allowing them to be read in
 258 /// from a [`Read`] given some additional set of arguments which is required to deserialize.
 259 ///
 260 /// This is not exported to bindings users as we only export serialization to/from byte arrays instead
 261 pub trait ReadableArgs<P>
 262         where Self: Sized
 263 {
 264         /// Reads a `Self` in from the given [`Read`].
 265         fn read<R: Read>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 266 }
 267
 268 /// A [`std::io::Read`] that also provides the total bytes available to be read.
 269 pub(crate) trait LengthRead: Read {
 270         /// The total number of bytes available to be read.
 271         fn total_bytes(&self) -> u64;
 272 }
 273
 274 /// A trait that various higher-level LDK types implement allowing them to be read in
 275 /// from a Read given some additional set of arguments which is required to deserialize, requiring
 276 /// the implementer to provide the total length of the read.
 277 pub(crate) trait LengthReadableArgs<P> where Self: Sized
 278 {
 279         /// Reads a `Self` in from the given [`LengthRead`].
 280         fn read<R: LengthRead>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 281 }
 282
 283 /// A trait that various higher-level LDK types implement allowing them to be read in
 284 /// from a [`Read`], requiring the implementer to provide the total length of the read.
 285 pub(crate) trait LengthReadable where Self: Sized
 286 {
 287         /// Reads a `Self` in from the given [`LengthRead`].
 288         fn read<R: LengthRead>(reader: &mut R) -> Result<Self, DecodeError>;
 289 }
 290
 291 /// A trait that various LDK types implement allowing them to (maybe) be read in from a [`Read`].
 292 ///
 293 /// This is not exported to bindings users as we only export serialization to/from byte arrays instead
 294 pub trait MaybeReadable
 295         where Self: Sized
 296 {
 297         /// Reads a `Self` in from the given [`Read`].
 298         fn read<R: Read>(reader: &mut R) -> Result<Option<Self>, DecodeError>;
 299 }
 300
 301 impl<T: Readable> MaybeReadable for T {
 302         #[inline]
 303         fn read<R: Read>(reader: &mut R) -> Result<Option<T>, DecodeError> {
 304                 Ok(Some(Readable::read(reader)?))
 305         }
 306 }
 307
 308 /// Wrapper to read a required (non-optional) TLV record.
 309 ///
 310 /// This is not exported to bindings users as manual TLV building is not currently supported in bindings
 311 pub struct RequiredWrapper<T>(pub Option<T>);
 312 impl<T: Readable> Readable for RequiredWrapper<T> {
 313         #[inline]
 314         fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
 315                 Ok(Self(Some(Readable::read(reader)?)))
 316         }
 317 }
 318 impl<A, T: ReadableArgs<A>> ReadableArgs<A> for RequiredWrapper<T> {
 319         #[inline]
 320         fn read<R: Read>(reader: &mut R, args: A) -> Result<Self, DecodeError> {
 321                 Ok(Self(Some(ReadableArgs::read(reader, args)?)))
 322         }
 323 }
 324 /// When handling `default_values`, we want to map the default-value T directly
 325 /// to a `RequiredWrapper<T>` in a way that works for `field: T = t;` as
 326 /// well. Thus, we assume `Into<T> for T` does nothing and use that.
 327 impl<T> From<T> for RequiredWrapper<T> {
 328         fn from(t: T) -> RequiredWrapper<T> { RequiredWrapper(Some(t)) }
 329 }
 330
 331 /// Wrapper to read a required (non-optional) TLV record that may have been upgraded without
 332 /// backwards compat.
 333 ///
 334 /// This is not exported to bindings users as manual TLV building is not currently supported in bindings
 335 pub struct UpgradableRequired<T: MaybeReadable>(pub Option<T>);
 336 impl<T: MaybeReadable> MaybeReadable for UpgradableRequired<T> {
 337         #[inline]
 338         fn read<R: Read>(reader: &mut R) -> Result<Option<Self>, DecodeError> {
 339                 let tlv = MaybeReadable::read(reader)?;
 340                 if let Some(tlv) = tlv { return Ok(Some(Self(Some(tlv)))) }
 341                 Ok(None)
 342         }
 343 }
 344
 345 pub(crate) struct U48(pub u64);
 346 impl Writeable for U48 {
 347         #[inline]
 348         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 349                 writer.write_all(&be48_to_array(self.0))
 350         }
 351 }
 352 impl Readable for U48 {
 353         #[inline]
 354         fn read<R: Read>(reader: &mut R) -> Result<U48, DecodeError> {
 355                 let mut buf = [0; 6];
 356                 reader.read_exact(&mut buf)?;
 357                 Ok(U48(slice_to_be48(&buf)))
 358         }
 359 }
 360
 361 /// Lightning TLV uses a custom variable-length integer called `BigSize`. It is similar to Bitcoin's
 362 /// variable-length integers except that it is serialized in big-endian instead of little-endian.
 363 ///
 364 /// Like Bitcoin's variable-length integer, it exhibits ambiguity in that certain values can be
 365 /// encoded in several different ways, which we must check for at deserialization-time. Thus, if
 366 /// you're looking for an example of a variable-length integer to use for your own project, move
 367 /// along, this is a rather poor design.
 368 #[derive(Clone, Copy, Debug, Hash, PartialOrd, Ord, PartialEq, Eq)]
 369 pub struct BigSize(pub u64);
 370 impl Writeable for BigSize {
 371         #[inline]
 372         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 373                 match self.0 {
 374                         0...0xFC => {
 375                                 (self.0 as u8).write(writer)
 376                         },
 377                         0xFD...0xFFFF => {
 378                                 0xFDu8.write(writer)?;
 379                                 (self.0 as u16).write(writer)
 380                         },
 381                         0x10000...0xFFFFFFFF => {
 382                                 0xFEu8.write(writer)?;
 383                                 (self.0 as u32).write(writer)
 384                         },
 385                         _ => {
 386                                 0xFFu8.write(writer)?;
 387                                 (self.0 as u64).write(writer)
 388                         },
 389                 }
 390         }
 391 }
 392 impl Readable for BigSize {
 393         #[inline]
 394         fn read<R: Read>(reader: &mut R) -> Result<BigSize, DecodeError> {
 395                 let n: u8 = Readable::read(reader)?;
 396                 match n {
 397                         0xFF => {
 398                                 let x: u64 = Readable::read(reader)?;
 399                                 if x < 0x100000000 {
 400                                         Err(DecodeError::InvalidValue)
 401                                 } else {
 402                                         Ok(BigSize(x))
 403                                 }
 404                         }
 405                         0xFE => {
 406                                 let x: u32 = Readable::read(reader)?;
 407                                 if x < 0x10000 {
 408                                         Err(DecodeError::InvalidValue)
 409                                 } else {
 410                                         Ok(BigSize(x as u64))
 411                                 }
 412                         }
 413                         0xFD => {
 414                                 let x: u16 = Readable::read(reader)?;
 415                                 if x < 0xFD {
 416                                         Err(DecodeError::InvalidValue)
 417                                 } else {
 418                                         Ok(BigSize(x as u64))
 419                                 }
 420                         }
 421                         n => Ok(BigSize(n as u64))
 422                 }
 423         }
 424 }
 425
 426 /// The lightning protocol uses u16s for lengths in most cases. As our serialization framework
 427 /// primarily targets that, we must as well. However, because we may serialize objects that have
 428 /// more than 65K entries, we need to be able to store larger values. Thus, we define a variable
 429 /// length integer here that is backwards-compatible for values < 0xffff. We treat 0xffff as
 430 /// "read eight more bytes".
 431 ///
 432 /// To ensure we only have one valid encoding per value, we add 0xffff to values written as eight
 433 /// bytes. Thus, 0xfffe is serialized as 0xfffe, whereas 0xffff is serialized as
 434 /// 0xffff0000000000000000 (i.e. read-eight-bytes then zero).
 435 struct CollectionLength(pub u64);
 436 impl Writeable for CollectionLength {
 437         #[inline]
 438         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 439                 if self.0 < 0xffff {
 440                         (self.0 as u16).write(writer)
 441                 } else {
 442                         0xffffu16.write(writer)?;
 443                         (self.0 - 0xffff).write(writer)
 444                 }
 445         }
 446 }
 447
 448 impl Readable for CollectionLength {
 449         #[inline]
 450         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 451                 let mut val: u64 = <u16 as Readable>::read(r)? as u64;
 452                 if val == 0xffff {
 453                         val = <u64 as Readable>::read(r)?
 454                                 .checked_add(0xffff).ok_or(DecodeError::InvalidValue)?;
 455                 }
 456                 Ok(CollectionLength(val))
 457         }
 458 }
 459
 460 /// In TLV we occasionally send fields which only consist of, or potentially end with, a
 461 /// variable-length integer which is simply truncated by skipping high zero bytes. This type
 462 /// encapsulates such integers implementing [`Readable`]/[`Writeable`] for them.
 463 #[cfg_attr(test, derive(PartialEq, Eq, Debug))]
 464 pub(crate) struct HighZeroBytesDroppedBigSize<T>(pub T);
 465
 466 macro_rules! impl_writeable_primitive {
 467         ($val_type:ty, $len: expr) => {
 468                 impl Writeable for $val_type {
 469                         #[inline]
 470                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 471                                 writer.write_all(&self.to_be_bytes())
 472                         }
 473                 }
 474                 impl Writeable for HighZeroBytesDroppedBigSize<$val_type> {
 475                         #[inline]
 476                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 477                                 // Skip any full leading 0 bytes when writing (in BE):
 478                                 writer.write_all(&self.0.to_be_bytes()[(self.0.leading_zeros()/8) as usize..$len])
 479                         }
 480                 }
 481                 impl Readable for $val_type {
 482                         #[inline]
 483                         fn read<R: Read>(reader: &mut R) -> Result<$val_type, DecodeError> {
 484                                 let mut buf = [0; $len];
 485                                 reader.read_exact(&mut buf)?;
 486                                 Ok(<$val_type>::from_be_bytes(buf))
 487                         }
 488                 }
 489                 impl Readable for HighZeroBytesDroppedBigSize<$val_type> {
 490                         #[inline]
 491                         fn read<R: Read>(reader: &mut R) -> Result<HighZeroBytesDroppedBigSize<$val_type>, DecodeError> {
 492                                 // We need to accept short reads (read_len == 0) as "EOF" and handle them as simply
 493                                 // the high bytes being dropped. To do so, we start reading into the middle of buf
 494                                 // and then convert the appropriate number of bytes with extra high bytes out of
 495                                 // buf.
 496                                 let mut buf = [0; $len*2];
 497                                 let mut read_len = reader.read(&mut buf[$len..])?;
 498                                 let mut total_read_len = read_len;
 499                                 while read_len != 0 && total_read_len != $len {
 500                                         read_len = reader.read(&mut buf[($len + total_read_len)..])?;
 501                                         total_read_len += read_len;
 502                                 }
 503                                 if total_read_len == 0 || buf[$len] != 0 {
 504                                         let first_byte = $len - ($len - total_read_len);
 505                                         let mut bytes = [0; $len];
 506                                         bytes.copy_from_slice(&buf[first_byte..first_byte + $len]);
 507                                         Ok(HighZeroBytesDroppedBigSize(<$val_type>::from_be_bytes(bytes)))
 508                                 } else {
 509                                         // If the encoding had extra zero bytes, return a failure even though we know
 510                                         // what they meant (as the TLV test vectors require this)
 511                                         Err(DecodeError::InvalidValue)
 512                                 }
 513                         }
 514                 }
 515                 impl From<$val_type> for HighZeroBytesDroppedBigSize<$val_type> {
 516                         fn from(val: $val_type) -> Self { Self(val) }
 517                 }
 518         }
 519 }
 520
 521 impl_writeable_primitive!(u128, 16);
 522 impl_writeable_primitive!(u64, 8);
 523 impl_writeable_primitive!(u32, 4);
 524 impl_writeable_primitive!(u16, 2);
 525 impl_writeable_primitive!(i64, 8);
 526 impl_writeable_primitive!(i32, 4);
 527 impl_writeable_primitive!(i16, 2);
 528 impl_writeable_primitive!(i8, 1);
 529
 530 impl Writeable for u8 {
 531         #[inline]
 532         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 533                 writer.write_all(&[*self])
 534         }
 535 }
 536 impl Readable for u8 {
 537         #[inline]
 538         fn read<R: Read>(reader: &mut R) -> Result<u8, DecodeError> {
 539                 let mut buf = [0; 1];
 540                 reader.read_exact(&mut buf)?;
 541                 Ok(buf[0])
 542         }
 543 }
 544
 545 impl Writeable for bool {
 546         #[inline]
 547         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 548                 writer.write_all(&[if *self {1} else {0}])
 549         }
 550 }
 551 impl Readable for bool {
 552         #[inline]
 553         fn read<R: Read>(reader: &mut R) -> Result<bool, DecodeError> {
 554                 let mut buf = [0; 1];
 555                 reader.read_exact(&mut buf)?;
 556                 if buf[0] != 0 && buf[0] != 1 {
 557                         return Err(DecodeError::InvalidValue);
 558                 }
 559                 Ok(buf[0] == 1)
 560         }
 561 }
 562
 563 macro_rules! impl_array {
 564         ($size:expr, $ty: ty) => (
 565                 impl Writeable for [$ty; $size] {
 566                         #[inline]
 567                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 568                                 let mut out = [0; $size * core::mem::size_of::<$ty>()];
 569                                 for (idx, v) in self.iter().enumerate() {
 570                                         let startpos = idx * core::mem::size_of::<$ty>();
 571                                         out[startpos..startpos + core::mem::size_of::<$ty>()].copy_from_slice(&v.to_be_bytes());
 572                                 }
 573                                 w.write_all(&out)
 574                         }
 575                 }
 576
 577                 impl Readable for [$ty; $size] {
 578                         #[inline]
 579                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 580                                 let mut buf = [0u8; $size * core::mem::size_of::<$ty>()];
 581                                 r.read_exact(&mut buf)?;
 582                                 let mut res = [0; $size];
 583                                 for (idx, v) in res.iter_mut().enumerate() {
 584                                         let startpos = idx * core::mem::size_of::<$ty>();
 585                                         let mut arr = [0; core::mem::size_of::<$ty>()];
 586                                         arr.copy_from_slice(&buf[startpos..startpos + core::mem::size_of::<$ty>()]);
 587                                         *v = <$ty>::from_be_bytes(arr);
 588                                 }
 589                                 Ok(res)
 590                         }
 591                 }
 592         );
 593 }
 594
 595 impl_array!(3, u8); // for rgb, ISO 4712 code
 596 impl_array!(4, u8); // for IPv4
 597 impl_array!(12, u8); // for OnionV2
 598 impl_array!(16, u8); // for IPv6
 599 impl_array!(32, u8); // for channel id & hmac
 600 impl_array!(PUBLIC_KEY_SIZE, u8); // for PublicKey
 601 impl_array!(64, u8); // for ecdsa::Signature and schnorr::Signature
 602 impl_array!(66, u8); // for MuSig2 nonces
 603 impl_array!(1300, u8); // for OnionPacket.hop_data
 604
 605 impl_array!(8, u16);
 606 impl_array!(32, u16);
 607
 608 /// A type for variable-length values within TLV record where the length is encoded as part of the record.
 609 /// Used to prevent encoding the length twice.
 610 ///
 611 /// This is not exported to bindings users as manual TLV building is not currently supported in bindings
 612 pub struct WithoutLength<T>(pub T);
 613
 614 impl Writeable for WithoutLength<&String> {
 615         #[inline]
 616         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 617                 w.write_all(self.0.as_bytes())
 618         }
 619 }
 620 impl Readable for WithoutLength<String> {
 621         #[inline]
 622         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 623                 let v: WithoutLength<Vec<u8>> = Readable::read(r)?;
 624                 Ok(Self(String::from_utf8(v.0).map_err(|_| DecodeError::InvalidValue)?))
 625         }
 626 }
 627 impl<'a> From<&'a String> for WithoutLength<&'a String> {
 628         fn from(s: &'a String) -> Self { Self(s) }
 629 }
 630
 631
 632 impl Writeable for WithoutLength<&UntrustedString> {
 633         #[inline]
 634         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 635                 WithoutLength(&self.0.0).write(w)
 636         }
 637 }
 638 impl Readable for WithoutLength<UntrustedString> {
 639         #[inline]
 640         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 641                 let s: WithoutLength<String> = Readable::read(r)?;
 642                 Ok(Self(UntrustedString(s.0)))
 643         }
 644 }
 645
 646 impl<'a, T: Writeable> Writeable for WithoutLength<&'a Vec<T>> {
 647         #[inline]
 648         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 649                 for ref v in self.0.iter() {
 650                         v.write(writer)?;
 651                 }
 652                 Ok(())
 653         }
 654 }
 655
 656 impl<T: MaybeReadable> Readable for WithoutLength<Vec<T>> {
 657         #[inline]
 658         fn read<R: Read>(mut reader: &mut R) -> Result<Self, DecodeError> {
 659                 let mut values = Vec::new();
 660                 loop {
 661                         let mut track_read = ReadTrackingReader::new(&mut reader);
 662                         match MaybeReadable::read(&mut track_read) {
 663                                 Ok(Some(v)) => { values.push(v); },
 664                                 Ok(None) => { },
 665                                 // If we failed to read any bytes at all, we reached the end of our TLV
 666                                 // stream and have simply exhausted all entries.
 667                                 Err(ref e) if e == &DecodeError::ShortRead && !track_read.have_read => break,
 668                                 Err(e) => return Err(e),
 669                         }
 670                 }
 671                 Ok(Self(values))
 672         }
 673 }
 674 impl<'a, T> From<&'a Vec<T>> for WithoutLength<&'a Vec<T>> {
 675         fn from(v: &'a Vec<T>) -> Self { Self(v) }
 676 }
 677
 678 impl Writeable for WithoutLength<&Script> {
 679         #[inline]
 680         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 681                 writer.write_all(self.0.as_bytes())
 682         }
 683 }
 684
 685 impl Readable for WithoutLength<Script> {
 686         #[inline]
 687         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 688                 let v: WithoutLength<Vec<u8>> = Readable::read(r)?;
 689                 Ok(WithoutLength(script::Builder::from(v.0).into_script()))
 690         }
 691 }
 692
 693 #[derive(Debug)]
 694 pub(crate) struct Iterable<'a, I: Iterator<Item = &'a T> + Clone, T: 'a>(pub I);
 695
 696 impl<'a, I: Iterator<Item = &'a T> + Clone, T: 'a + Writeable> Writeable for Iterable<'a, I, T> {
 697         #[inline]
 698         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 699                 for ref v in self.0.clone() {
 700                         v.write(writer)?;
 701                 }
 702                 Ok(())
 703         }
 704 }
 705
 706 #[cfg(test)]
 707 impl<'a, I: Iterator<Item = &'a T> + Clone, T: 'a + PartialEq> PartialEq for Iterable<'a, I, T> {
 708         fn eq(&self, other: &Self) -> bool {
 709                 self.0.clone().collect::<Vec<_>>() == other.0.clone().collect::<Vec<_>>()
 710         }
 711 }
 712
 713 macro_rules! impl_for_map {
 714         ($ty: ident, $keybound: ident, $constr: expr) => {
 715                 impl<K, V> Writeable for $ty<K, V>
 716                         where K: Writeable + Eq + $keybound, V: Writeable
 717                 {
 718                         #[inline]
 719                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 720                                 CollectionLength(self.len() as u64).write(w)?;
 721                                 for (key, value) in self.iter() {
 722                                         key.write(w)?;
 723                                         value.write(w)?;
 724                                 }
 725                                 Ok(())
 726                         }
 727                 }
 728
 729                 impl<K, V> Readable for $ty<K, V>
 730                         where K: Readable + Eq + $keybound, V: MaybeReadable
 731                 {
 732                         #[inline]
 733                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 734                                 let len: CollectionLength = Readable::read(r)?;
 735                                 let mut ret = $constr(len.0 as usize);
 736                                 for _ in 0..len.0 {
 737                                         let k = K::read(r)?;
 738                                         let v_opt = V::read(r)?;
 739                                         if let Some(v) = v_opt {
 740                                                 if ret.insert(k, v).is_some() {
 741                                                         return Err(DecodeError::InvalidValue);
 742                                                 }
 743                                         }
 744                                 }
 745                                 Ok(ret)
 746                         }
 747                 }
 748         }
 749 }
 750
 751 impl_for_map!(BTreeMap, Ord, |_| BTreeMap::new());
 752 impl_for_map!(HashMap, Hash, |len| HashMap::with_capacity(len));
 753
 754 // HashSet
 755 impl<T> Writeable for HashSet<T>
 756 where T: Writeable + Eq + Hash
 757 {
 758         #[inline]
 759         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 760                 CollectionLength(self.len() as u64).write(w)?;
 761                 for item in self.iter() {
 762                         item.write(w)?;
 763                 }
 764                 Ok(())
 765         }
 766 }
 767
 768 impl<T> Readable for HashSet<T>
 769 where T: Readable + Eq + Hash
 770 {
 771         #[inline]
 772         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 773                 let len: CollectionLength = Readable::read(r)?;
 774                 let mut ret = HashSet::with_capacity(cmp::min(len.0 as usize, MAX_BUF_SIZE / core::mem::size_of::<T>()));
 775                 for _ in 0..len.0 {
 776                         if !ret.insert(T::read(r)?) {
 777                                 return Err(DecodeError::InvalidValue)
 778                         }
 779                 }
 780                 Ok(ret)
 781         }
 782 }
 783
 784 // Vectors
 785 macro_rules! impl_writeable_for_vec {
 786         ($ty: ty $(, $name: ident)*) => {
 787                 impl<$($name : Writeable),*> Writeable for Vec<$ty> {
 788                         #[inline]
 789                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 790                                 CollectionLength(self.len() as u64).write(w)?;
 791                                 for elem in self.iter() {
 792                                         elem.write(w)?;
 793                                 }
 794                                 Ok(())
 795                         }
 796                 }
 797         }
 798 }
 799 macro_rules! impl_readable_for_vec {
 800         ($ty: ty $(, $name: ident)*) => {
 801                 impl<$($name : Readable),*> Readable for Vec<$ty> {
 802                         #[inline]
 803                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 804                                 let len: CollectionLength = Readable::read(r)?;
 805                                 let mut ret = Vec::with_capacity(cmp::min(len.0 as usize, MAX_BUF_SIZE / core::mem::size_of::<$ty>()));
 806                                 for _ in 0..len.0 {
 807                                         if let Some(val) = MaybeReadable::read(r)? {
 808                                                 ret.push(val);
 809                                         }
 810                                 }
 811                                 Ok(ret)
 812                         }
 813                 }
 814         }
 815 }
 816 macro_rules! impl_for_vec {
 817         ($ty: ty $(, $name: ident)*) => {
 818                 impl_writeable_for_vec!($ty $(, $name)*);
 819                 impl_readable_for_vec!($ty $(, $name)*);
 820         }
 821 }
 822
 823 impl Writeable for Vec<u8> {
 824         #[inline]
 825         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 826                 CollectionLength(self.len() as u64).write(w)?;
 827                 w.write_all(&self)
 828         }
 829 }
 830
 831 impl Readable for Vec<u8> {
 832         #[inline]
 833         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 834                 let mut len: CollectionLength = Readable::read(r)?;
 835                 let mut ret = Vec::new();
 836                 while len.0 > 0 {
 837                         let readamt = cmp::min(len.0 as usize, MAX_BUF_SIZE);
 838                         let readstart = ret.len();
 839                         ret.resize(readstart + readamt, 0);
 840                         r.read_exact(&mut ret[readstart..])?;
 841                         len.0 -= readamt as u64;
 842                 }
 843                 Ok(ret)
 844         }
 845 }
 846
 847 impl_for_vec!(ecdsa::Signature);
 848 impl_for_vec!(crate::chain::channelmonitor::ChannelMonitorUpdate);
 849 impl_for_vec!(crate::ln::channelmanager::MonitorUpdateCompletionAction);
 850 impl_for_vec!((A, B), A, B);
 851 impl_writeable_for_vec!(&crate::routing::router::BlindedTail);
 852 impl_readable_for_vec!(crate::routing::router::BlindedTail);
 853
 854 impl Writeable for Vec<Witness> {
 855         #[inline]
 856         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 857                 (self.len() as u16).write(w)?;
 858                 for witness in self {
 859                         (witness.serialized_len() as u16).write(w)?;
 860                         witness.write(w)?;
 861                 }
 862                 Ok(())
 863         }
 864 }
 865
 866 impl Readable for Vec<Witness> {
 867         #[inline]
 868         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 869                 let num_witnesses = <u16 as Readable>::read(r)? as usize;
 870                 let mut witnesses = Vec::with_capacity(num_witnesses);
 871                 for _ in 0..num_witnesses {
 872                         // Even though the length of each witness can be inferred in its consensus-encoded form,
 873                         // the spec includes a length prefix so that implementations don't have to deserialize
 874                         //  each initially. We do that here anyway as in general we'll need to be able to make
 875                         // assertions on some properties of the witnesses when receiving a message providing a list
 876                         // of witnesses. We'll just do a sanity check for the lengths and error if there is a mismatch.
 877                         let witness_len = <u16 as Readable>::read(r)? as usize;
 878                         let witness = <Witness as Readable>::read(r)?;
 879                         if witness.serialized_len() != witness_len {
 880                                 return Err(DecodeError::BadLengthDescriptor);
 881                         }
 882                         witnesses.push(witness);
 883                 }
 884                 Ok(witnesses)
 885         }
 886 }
 887
 888 impl Writeable for Script {
 889         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 890                 (self.len() as u16).write(w)?;
 891                 w.write_all(self.as_bytes())
 892         }
 893 }
 894
 895 impl Readable for Script {
 896         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 897                 let len = <u16 as Readable>::read(r)? as usize;
 898                 let mut buf = vec![0; len];
 899                 r.read_exact(&mut buf)?;
 900                 Ok(Script::from(buf))
 901         }
 902 }
 903
 904 impl Writeable for PublicKey {
 905         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 906                 self.serialize().write(w)
 907         }
 908         #[inline]
 909         fn serialized_length(&self) -> usize {
 910                 PUBLIC_KEY_SIZE
 911         }
 912 }
 913
 914 impl Readable for PublicKey {
 915         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 916                 let buf: [u8; PUBLIC_KEY_SIZE] = Readable::read(r)?;
 917                 match PublicKey::from_slice(&buf) {
 918                         Ok(key) => Ok(key),
 919                         Err(_) => return Err(DecodeError::InvalidValue),
 920                 }
 921         }
 922 }
 923
 924 impl Writeable for SecretKey {
 925         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 926                 let mut ser = [0; SECRET_KEY_SIZE];
 927                 ser.copy_from_slice(&self[..]);
 928                 ser.write(w)
 929         }
 930         #[inline]
 931         fn serialized_length(&self) -> usize {
 932                 SECRET_KEY_SIZE
 933         }
 934 }
 935
 936 impl Readable for SecretKey {
 937         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 938                 let buf: [u8; SECRET_KEY_SIZE] = Readable::read(r)?;
 939                 match SecretKey::from_slice(&buf) {
 940                         Ok(key) => Ok(key),
 941                         Err(_) => return Err(DecodeError::InvalidValue),
 942                 }
 943         }
 944 }
 945
 946 #[cfg(taproot)]
 947 impl Writeable for musig2::types::PublicNonce {
 948         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 949                 self.serialize().write(w)
 950         }
 951 }
 952
 953 #[cfg(taproot)]
 954 impl Readable for musig2::types::PublicNonce {
 955         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 956                 let buf: [u8; PUBLIC_KEY_SIZE * 2] = Readable::read(r)?;
 957                 musig2::types::PublicNonce::from_slice(&buf).map_err(|_| DecodeError::InvalidValue)
 958         }
 959 }
 960
 961 #[cfg(taproot)]
 962 impl Writeable for PartialSignatureWithNonce {
 963         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 964                 self.0.serialize().write(w)?;
 965                 self.1.write(w)
 966         }
 967 }
 968
 969 #[cfg(taproot)]
 970 impl Readable for PartialSignatureWithNonce {
 971         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 972                 let partial_signature_buf: [u8; SECRET_KEY_SIZE] = Readable::read(r)?;
 973                 let partial_signature = musig2::types::PartialSignature::from_slice(&partial_signature_buf).map_err(|_| DecodeError::InvalidValue)?;
 974                 let public_nonce: musig2::types::PublicNonce = Readable::read(r)?;
 975                 Ok(PartialSignatureWithNonce(partial_signature, public_nonce))
 976         }
 977 }
 978
 979 impl Writeable for Sha256dHash {
 980         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 981                 w.write_all(&self[..])
 982         }
 983 }
 984
 985 impl Readable for Sha256dHash {
 986         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 987                 use bitcoin::hashes::Hash;
 988
 989                 let buf: [u8; 32] = Readable::read(r)?;
 990                 Ok(Sha256dHash::from_slice(&buf[..]).unwrap())
 991         }
 992 }
 993
 994 impl Writeable for ecdsa::Signature {
 995         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 996                 self.serialize_compact().write(w)
 997         }
 998 }
 999
1000 impl Readable for ecdsa::Signature {
1001         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1002                 let buf: [u8; COMPACT_SIGNATURE_SIZE] = Readable::read(r)?;
1003                 match ecdsa::Signature::from_compact(&buf) {
1004                         Ok(sig) => Ok(sig),
1005                         Err(_) => return Err(DecodeError::InvalidValue),
1006                 }
1007         }
1008 }
1009
1010 impl Writeable for schnorr::Signature {
1011         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1012                 self.as_ref().write(w)
1013         }
1014 }
1015
1016 impl Readable for schnorr::Signature {
1017         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1018                 let buf: [u8; SCHNORR_SIGNATURE_SIZE] = Readable::read(r)?;
1019                 match schnorr::Signature::from_slice(&buf) {
1020                         Ok(sig) => Ok(sig),
1021                         Err(_) => return Err(DecodeError::InvalidValue),
1022                 }
1023         }
1024 }
1025
1026 impl Writeable for PaymentPreimage {
1027         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1028                 self.0.write(w)
1029         }
1030 }
1031
1032 impl Readable for PaymentPreimage {
1033         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1034                 let buf: [u8; 32] = Readable::read(r)?;
1035                 Ok(PaymentPreimage(buf))
1036         }
1037 }
1038
1039 impl Writeable for PaymentHash {
1040         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1041                 self.0.write(w)
1042         }
1043 }
1044
1045 impl Readable for PaymentHash {
1046         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1047                 let buf: [u8; 32] = Readable::read(r)?;
1048                 Ok(PaymentHash(buf))
1049         }
1050 }
1051
1052 impl Writeable for PaymentSecret {
1053         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1054                 self.0.write(w)
1055         }
1056 }
1057
1058 impl Readable for PaymentSecret {
1059         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1060                 let buf: [u8; 32] = Readable::read(r)?;
1061                 Ok(PaymentSecret(buf))
1062         }
1063 }
1064
1065 impl<T: Writeable> Writeable for Box<T> {
1066         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1067                 T::write(&**self, w)
1068         }
1069 }
1070
1071 impl<T: Readable> Readable for Box<T> {
1072         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1073                 Ok(Box::new(Readable::read(r)?))
1074         }
1075 }
1076
1077 impl<T: Writeable> Writeable for Option<T> {
1078         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1079                 match *self {
1080                         None => 0u8.write(w)?,
1081                         Some(ref data) => {
1082                                 BigSize(data.serialized_length() as u64 + 1).write(w)?;
1083                                 data.write(w)?;
1084                         }
1085                 }
1086                 Ok(())
1087         }
1088 }
1089
1090 impl<T: Readable> Readable for Option<T>
1091 {
1092         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1093                 let len: BigSize = Readable::read(r)?;
1094                 match len.0 {
1095                         0 => Ok(None),
1096                         len => {
1097                                 let mut reader = FixedLengthReader::new(r, len - 1);
1098                                 Ok(Some(Readable::read(&mut reader)?))
1099                         }
1100                 }
1101         }
1102 }
1103
1104 impl Writeable for Txid {
1105         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1106                 w.write_all(&self[..])
1107         }
1108 }
1109
1110 impl Readable for Txid {
1111         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1112                 use bitcoin::hashes::Hash;
1113
1114                 let buf: [u8; 32] = Readable::read(r)?;
1115                 Ok(Txid::from_slice(&buf[..]).unwrap())
1116         }
1117 }
1118
1119 impl Writeable for BlockHash {
1120         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1121                 w.write_all(&self[..])
1122         }
1123 }
1124
1125 impl Readable for BlockHash {
1126         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1127                 use bitcoin::hashes::Hash;
1128
1129                 let buf: [u8; 32] = Readable::read(r)?;
1130                 Ok(BlockHash::from_slice(&buf[..]).unwrap())
1131         }
1132 }
1133
1134 impl Writeable for ChainHash {
1135         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1136                 w.write_all(self.as_bytes())
1137         }
1138 }
1139
1140 impl Readable for ChainHash {
1141         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1142                 let buf: [u8; 32] = Readable::read(r)?;
1143                 Ok(ChainHash::from(&buf[..]))
1144         }
1145 }
1146
1147 impl Writeable for OutPoint {
1148         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1149                 self.txid.write(w)?;
1150                 self.vout.write(w)?;
1151                 Ok(())
1152         }
1153 }
1154
1155 impl Readable for OutPoint {
1156         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1157                 let txid = Readable::read(r)?;
1158                 let vout = Readable::read(r)?;
1159                 Ok(OutPoint {
1160                         txid,
1161                         vout,
1162                 })
1163         }
1164 }
1165
1166 macro_rules! impl_consensus_ser {
1167         ($bitcoin_type: ty) => {
1168                 impl Writeable for $bitcoin_type {
1169                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1170                                 match self.consensus_encode(&mut WriterWriteAdaptor(writer)) {
1171                                         Ok(_) => Ok(()),
1172                                         Err(e) => Err(e),
1173                                 }
1174                         }
1175                 }
1176
1177                 impl Readable for $bitcoin_type {
1178                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1179                                 match consensus::encode::Decodable::consensus_decode(r) {
1180                                         Ok(t) => Ok(t),
1181                                         Err(consensus::encode::Error::Io(ref e)) if e.kind() == io::ErrorKind::UnexpectedEof => Err(DecodeError::ShortRead),
1182                                         Err(consensus::encode::Error::Io(e)) => Err(DecodeError::Io(e.kind())),
1183                                         Err(_) => Err(DecodeError::InvalidValue),
1184                                 }
1185                         }
1186                 }
1187         }
1188 }
1189 impl_consensus_ser!(Transaction);
1190 impl_consensus_ser!(TxOut);
1191 impl_consensus_ser!(Witness);
1192
1193 impl<T: Readable> Readable for Mutex<T> {
1194         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1195                 let t: T = Readable::read(r)?;
1196                 Ok(Mutex::new(t))
1197         }
1198 }
1199 impl<T: Writeable> Writeable for Mutex<T> {
1200         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1201                 self.lock().unwrap().write(w)
1202         }
1203 }
1204
1205 impl<T: Readable> Readable for RwLock<T> {
1206         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1207                 let t: T = Readable::read(r)?;
1208                 Ok(RwLock::new(t))
1209         }
1210 }
1211 impl<T: Writeable> Writeable for RwLock<T> {
1212         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1213                 self.read().unwrap().write(w)
1214         }
1215 }
1216
1217 impl<A: Readable, B: Readable> Readable for (A, B) {
1218         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1219                 let a: A = Readable::read(r)?;
1220                 let b: B = Readable::read(r)?;
1221                 Ok((a, b))
1222         }
1223 }
1224 impl<A: Writeable, B: Writeable> Writeable for (A, B) {
1225         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1226                 self.0.write(w)?;
1227                 self.1.write(w)
1228         }
1229 }
1230
1231 impl<A: Readable, B: Readable, C: Readable> Readable for (A, B, C) {
1232         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1233                 let a: A = Readable::read(r)?;
1234                 let b: B = Readable::read(r)?;
1235                 let c: C = Readable::read(r)?;
1236                 Ok((a, b, c))
1237         }
1238 }
1239 impl<A: Writeable, B: Writeable, C: Writeable> Writeable for (A, B, C) {
1240         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1241                 self.0.write(w)?;
1242                 self.1.write(w)?;
1243                 self.2.write(w)
1244         }
1245 }
1246
1247 impl<A: Readable, B: Readable, C: Readable, D: Readable> Readable for (A, B, C, D) {
1248         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1249                 let a: A = Readable::read(r)?;
1250                 let b: B = Readable::read(r)?;
1251                 let c: C = Readable::read(r)?;
1252                 let d: D = Readable::read(r)?;
1253                 Ok((a, b, c, d))
1254         }
1255 }
1256 impl<A: Writeable, B: Writeable, C: Writeable, D: Writeable> Writeable for (A, B, C, D) {
1257         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1258                 self.0.write(w)?;
1259                 self.1.write(w)?;
1260                 self.2.write(w)?;
1261                 self.3.write(w)
1262         }
1263 }
1264
1265 impl Writeable for () {
1266         fn write<W: Writer>(&self, _: &mut W) -> Result<(), io::Error> {
1267                 Ok(())
1268         }
1269 }
1270 impl Readable for () {
1271         fn read<R: Read>(_r: &mut R) -> Result<Self, DecodeError> {
1272                 Ok(())
1273         }
1274 }
1275
1276 impl Writeable for String {
1277         #[inline]
1278         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1279                 CollectionLength(self.len() as u64).write(w)?;
1280                 w.write_all(self.as_bytes())
1281         }
1282 }
1283 impl Readable for String {
1284         #[inline]
1285         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1286                 let v: Vec<u8> = Readable::read(r)?;
1287                 let ret = String::from_utf8(v).map_err(|_| DecodeError::InvalidValue)?;
1288                 Ok(ret)
1289         }
1290 }
1291
1292 /// Represents a hostname for serialization purposes.
1293 /// Only the character set and length will be validated.
1294 /// The character set consists of ASCII alphanumeric characters, hyphens, and periods.
1295 /// Its length is guaranteed to be representable by a single byte.
1296 /// This serialization is used by [`BOLT 7`] hostnames.
1297 ///
1298 /// [`BOLT 7`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md
1299 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
1300 pub struct Hostname(String);
1301 impl Hostname {
1302         /// Returns the length of the hostname.
1303         pub fn len(&self) -> u8 {
1304                 (&self.0).len() as u8
1305         }
1306 }
1307
1308 impl core::fmt::Display for Hostname {
1309         fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
1310                 write!(f, "{}", self.0)?;
1311                 Ok(())
1312         }
1313 }
1314 impl Deref for Hostname {
1315         type Target = String;
1316
1317         fn deref(&self) -> &Self::Target {
1318                 &self.0
1319         }
1320 }
1321 impl From<Hostname> for String {
1322         fn from(hostname: Hostname) -> Self {
1323                 hostname.0
1324         }
1325 }
1326 impl TryFrom<Vec<u8>> for Hostname {
1327         type Error = ();
1328
1329         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1330                 if let Ok(s) = String::from_utf8(bytes) {
1331                         Hostname::try_from(s)
1332                 } else {
1333                         Err(())
1334                 }
1335         }
1336 }
1337 impl TryFrom<String> for Hostname {
1338         type Error = ();
1339
1340         fn try_from(s: String) -> Result<Self, Self::Error> {
1341                 if s.len() <= 255 && s.chars().all(|c|
1342                         c.is_ascii_alphanumeric() ||
1343                         c == '.' ||
1344                         c == '-'
1345                 ) {
1346                         Ok(Hostname(s))
1347                 } else {
1348                         Err(())
1349                 }
1350         }
1351 }
1352 impl Writeable for Hostname {
1353         #[inline]
1354         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1355                 self.len().write(w)?;
1356                 w.write_all(self.as_bytes())
1357         }
1358 }
1359 impl Readable for Hostname {
1360         #[inline]
1361         fn read<R: Read>(r: &mut R) -> Result<Hostname, DecodeError> {
1362                 let len: u8 = Readable::read(r)?;
1363                 let mut vec = Vec::with_capacity(len.into());
1364                 vec.resize(len.into(), 0);
1365                 r.read_exact(&mut vec)?;
1366                 Hostname::try_from(vec).map_err(|_| DecodeError::InvalidValue)
1367         }
1368 }
1369
1370 /// This is not exported to bindings users as `Duration`s are simply mapped as ints.
1371 impl Writeable for Duration {
1372         #[inline]
1373         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1374                 self.as_secs().write(w)?;
1375                 self.subsec_nanos().write(w)
1376         }
1377 }
1378 /// This is not exported to bindings users as `Duration`s are simply mapped as ints.
1379 impl Readable for Duration {
1380         #[inline]
1381         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1382                 let secs = Readable::read(r)?;
1383                 let nanos = Readable::read(r)?;
1384                 Ok(Duration::new(secs, nanos))
1385         }
1386 }
1387
1388 /// A wrapper for a `Transaction` which can only be constructed with [`TransactionU16LenLimited::new`]
1389 /// if the `Transaction`'s consensus-serialized length is <= u16::MAX.
1390 ///
1391 /// Use [`TransactionU16LenLimited::into_transaction`] to convert into the contained `Transaction`.
1392 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
1393 pub struct TransactionU16LenLimited(Transaction);
1394
1395 impl TransactionU16LenLimited {
1396         /// Constructs a new `TransactionU16LenLimited` from a `Transaction` only if it's consensus-
1397         /// serialized length is <= u16::MAX.
1398         pub fn new(transaction: Transaction) -> Result<Self, ()> {
1399                 if transaction.serialized_length() > (u16::MAX as usize) {
1400                         Err(())
1401                 } else {
1402                         Ok(Self(transaction))
1403                 }
1404         }
1405
1406         /// Consumes this `TransactionU16LenLimited` and returns its contained `Transaction`.
1407         pub fn into_transaction(self) -> Transaction {
1408                 self.0
1409         }
1410 }
1411
1412 impl Writeable for TransactionU16LenLimited {
1413         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1414                 (self.0.serialized_length() as u16).write(w)?;
1415                 self.0.write(w)
1416         }
1417 }
1418
1419 impl Readable for TransactionU16LenLimited {
1420         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1421                 let len = <u16 as Readable>::read(r)?;
1422                 let mut tx_reader = FixedLengthReader::new(r, len as u64);
1423                 let tx: Transaction = Readable::read(&mut tx_reader)?;
1424                 if tx_reader.bytes_remain() {
1425                         Err(DecodeError::BadLengthDescriptor)
1426                 } else {
1427                         Ok(Self(tx))
1428                 }
1429         }
1430 }
1431
1432 impl Writeable for ClaimId {
1433         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1434                 self.0.write(writer)
1435         }
1436 }
1437
1438 impl Readable for ClaimId {
1439         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
1440                 Ok(Self(Readable::read(reader)?))
1441         }
1442 }
1443
1444 #[cfg(test)]
1445 mod tests {
1446         use core::convert::TryFrom;
1447         use bitcoin::secp256k1::ecdsa;
1448         use crate::util::ser::{Readable, Hostname, Writeable};
1449
1450         #[test]
1451         fn hostname_conversion() {
1452                 assert_eq!(Hostname::try_from(String::from("a-test.com")).unwrap().as_str(), "a-test.com");
1453
1454                 assert!(Hostname::try_from(String::from("\"")).is_err());
1455                 assert!(Hostname::try_from(String::from("$")).is_err());
1456                 assert!(Hostname::try_from(String::from("⚡")).is_err());
1457                 let mut large_vec = Vec::with_capacity(256);
1458                 large_vec.resize(256, b'A');
1459                 assert!(Hostname::try_from(String::from_utf8(large_vec).unwrap()).is_err());
1460         }
1461
1462         #[test]
1463         fn hostname_serialization() {
1464                 let hostname = Hostname::try_from(String::from("test")).unwrap();
1465                 let mut buf: Vec<u8> = Vec::new();
1466                 hostname.write(&mut buf).unwrap();
1467                 assert_eq!(Hostname::read(&mut buf.as_slice()).unwrap().as_str(), "test");
1468         }
1469
1470         #[test]
1471         /// Taproot will likely fill legacy signature fields with all 0s.
1472         /// This test ensures that doing so won't break serialization.
1473         fn null_signature_codec() {
1474                 let buffer = vec![0u8; 64];
1475                 let mut cursor = crate::io::Cursor::new(buffer.clone());
1476                 let signature = ecdsa::Signature::read(&mut cursor).unwrap();
1477                 let serialization = signature.serialize_compact();
1478                 assert_eq!(buffer, serialization.to_vec())
1479         }
1480
1481         #[test]
1482         fn bigsize_encoding_decoding() {
1483                 let values = vec![0, 252, 253, 65535, 65536, 4294967295, 4294967296, 18446744073709551615];
1484                 let bytes = vec![
1485                         "00",
1486                         "fc",
1487                         "fd00fd",
1488                         "fdffff",
1489                         "fe00010000",
1490                         "feffffffff",
1491                         "ff0000000100000000",
1492                         "ffffffffffffffffff"
1493                 ];
1494                 for i in 0..=7 {
1495                         let mut stream = crate::io::Cursor::new(::hex::decode(bytes[i]).unwrap());
1496                         assert_eq!(super::BigSize::read(&mut stream).unwrap().0, values[i]);
1497                         let mut stream = super::VecWriter(Vec::new());
1498                         super::BigSize(values[i]).write(&mut stream).unwrap();
1499                         assert_eq!(stream.0, ::hex::decode(bytes[i]).unwrap());
1500                 }
1501                 let err_bytes = vec![
1502                         "fd00fc",
1503                         "fe0000ffff",
1504                         "ff00000000ffffffff",
1505                         "fd00",
1506                         "feffff",
1507                         "ffffffffff",
1508                         "fd",
1509                         "fe",
1510                         "ff",
1511                         ""
1512                 ];
1513                 for i in 0..=9 {
1514                         let mut stream = crate::io::Cursor::new(::hex::decode(err_bytes[i]).unwrap());
1515                         if i < 3 {
1516                                 assert_eq!(super::BigSize::read(&mut stream).err(), Some(crate::ln::msgs::DecodeError::InvalidValue));
1517                         } else {
1518                                 assert_eq!(super::BigSize::read(&mut stream).err(), Some(crate::ln::msgs::DecodeError::ShortRead));
1519                         }
1520                 }
1521         }
1522 }