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