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