_ Git - rust-lightning/blob - lightning/src/util/ser.rs

   1 // This file is Copyright its original authors, visible in version control
   2 // history.
   3 //
   4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
   5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
   7 // You may not use this file except in accordance with one or both of these
   8 // licenses.
   9
  10 //! A very simple serialization framework which is used to serialize/deserialize messages as well
  11 //! as [`ChannelManager`]s and [`ChannelMonitor`]s.
  12 //!
  13 //! [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
  14 //! [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
  15
  16 use crate::prelude::*;
  17 use crate::io::{self, Read, Seek, Write};
  18 use crate::io_extras::{copy, sink};
  19 use core::hash::Hash;
  20 use crate::sync::{Mutex, RwLock};
  21 use core::cmp;
  22 use core::ops::Deref;
  23
  24 use alloc::collections::BTreeMap;
  25
  26 use bitcoin::secp256k1::{PublicKey, SecretKey};
  27 use bitcoin::secp256k1::constants::{PUBLIC_KEY_SIZE, SECRET_KEY_SIZE, COMPACT_SIGNATURE_SIZE, SCHNORR_SIGNATURE_SIZE};
  28 use bitcoin::secp256k1::ecdsa;
  29 use bitcoin::secp256k1::schnorr;
  30 use bitcoin::blockdata::constants::ChainHash;
  31 use bitcoin::blockdata::script::{self, ScriptBuf};
  32 use bitcoin::blockdata::transaction::{OutPoint, Transaction, TxOut};
  33 use bitcoin::{consensus, Witness};
  34 use bitcoin::consensus::Encodable;
  35 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
  36 use bitcoin::hash_types::{Txid, BlockHash};
  37 use core::time::Duration;
  38 use crate::chain::ClaimId;
  39 use crate::ln::msgs::DecodeError;
  40 #[cfg(taproot)]
  41 use crate::ln::msgs::PartialSignatureWithNonce;
  42 use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
  43
  44 use crate::util::byte_utils::{be48_to_array, slice_to_be48};
  45 use crate::util::string::UntrustedString;
  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<'a, R: Read> {
 110         read: &'a mut R,
 111         bytes_read: u64,
 112         total_bytes: u64,
 113 }
 114 impl<'a, R: Read> FixedLengthReader<'a, R> {
 115         /// Returns a new [`FixedLengthReader`].
 116         pub fn new(read: &'a mut 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<'a, R: Read> Read for FixedLengthReader<'a, 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<'a, R: Read> LengthRead for FixedLengthReader<'a, 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 len = self.serialized_length();
 201                 let mut msg = VecWriter(Vec::with_capacity(len));
 202                 self.write(&mut msg).unwrap();
 203                 // Note that objects with interior mutability may change size between when we called
 204                 // serialized_length and when we called write. That's okay, but shouldn't happen during
 205                 // testing as most of our tests are not threaded.
 206                 #[cfg(test)]
 207                 debug_assert_eq!(len, msg.0.len());
 208                 msg.0
 209         }
 210
 211         /// Writes `self` out to a `Vec<u8>`.
 212         #[cfg(test)]
 213         fn encode_with_len(&self) -> Vec<u8> {
 214                 let mut msg = VecWriter(Vec::new());
 215                 0u16.write(&mut msg).unwrap();
 216                 self.write(&mut msg).unwrap();
 217                 let len = msg.0.len();
 218                 debug_assert_eq!(len - 2, self.serialized_length());
 219                 msg.0[..2].copy_from_slice(&(len as u16 - 2).to_be_bytes());
 220                 msg.0
 221         }
 222
 223         /// Gets the length of this object after it has been serialized. This can be overridden to
 224         /// optimize cases where we prepend an object with its length.
 225         // Note that LLVM optimizes this away in most cases! Check that it isn't before you override!
 226         #[inline]
 227         fn serialized_length(&self) -> usize {
 228                 let mut len_calc = LengthCalculatingWriter(0);
 229                 self.write(&mut len_calc).expect("No in-memory data may fail to serialize");
 230                 len_calc.0
 231         }
 232 }
 233
 234 impl<'a, T: Writeable> Writeable for &'a T {
 235         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { (*self).write(writer) }
 236 }
 237
 238 /// A trait that various LDK types implement allowing them to be read in from a [`Read`].
 239 ///
 240 /// This is not exported to bindings users as we only export serialization to/from byte arrays instead
 241 pub trait Readable
 242         where Self: Sized
 243 {
 244         /// Reads a `Self` in from the given [`Read`].
 245         fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError>;
 246 }
 247
 248 /// A trait that various LDK types implement allowing them to be read in from a
 249 /// [`Read`]` + `[`Seek`].
 250 pub(crate) trait SeekReadable where Self: Sized {
 251         /// Reads a `Self` in from the given [`Read`].
 252         fn read<R: Read + Seek>(reader: &mut R) -> Result<Self, DecodeError>;
 253 }
 254
 255 /// A trait that various higher-level LDK types implement allowing them to be read in
 256 /// from a [`Read`] given some additional set of arguments which is required to deserialize.
 257 ///
 258 /// This is not exported to bindings users as we only export serialization to/from byte arrays instead
 259 pub trait ReadableArgs<P>
 260         where Self: Sized
 261 {
 262         /// Reads a `Self` in from the given [`Read`].
 263         fn read<R: Read>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 264 }
 265
 266 /// A [`std::io::Read`] that also provides the total bytes available to be read.
 267 pub(crate) trait LengthRead: Read {
 268         /// The total number of bytes available to be read.
 269         fn total_bytes(&self) -> u64;
 270 }
 271
 272 /// A trait that various higher-level LDK types implement allowing them to be read in
 273 /// from a Read given some additional set of arguments which is required to deserialize, requiring
 274 /// the implementer to provide the total length of the read.
 275 pub(crate) trait LengthReadableArgs<P> where Self: Sized
 276 {
 277         /// Reads a `Self` in from the given [`LengthRead`].
 278         fn read<R: LengthRead>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 279 }
 280
 281 /// A trait that various higher-level LDK types implement allowing them to be read in
 282 /// from a [`Read`], requiring the implementer to provide the total length of the read.
 283 pub(crate) trait LengthReadable where Self: Sized
 284 {
 285         /// Reads a `Self` in from the given [`LengthRead`].
 286         fn read<R: LengthRead>(reader: &mut R) -> Result<Self, DecodeError>;
 287 }
 288
 289 /// A trait that various LDK types implement allowing them to (maybe) be read in from a [`Read`].
 290 ///
 291 /// This is not exported to bindings users as we only export serialization to/from byte arrays instead
 292 pub trait MaybeReadable
 293         where Self: Sized
 294 {
 295         /// Reads a `Self` in from the given [`Read`].
 296         fn read<R: Read>(reader: &mut R) -> Result<Option<Self>, DecodeError>;
 297 }
 298
 299 impl<T: Readable> MaybeReadable for T {
 300         #[inline]
 301         fn read<R: Read>(reader: &mut R) -> Result<Option<T>, DecodeError> {
 302                 Ok(Some(Readable::read(reader)?))
 303         }
 304 }
 305
 306 /// Wrapper to read a required (non-optional) TLV record.
 307 ///
 308 /// This is not exported to bindings users as manual TLV building is not currently supported in bindings
 309 pub struct RequiredWrapper<T>(pub Option<T>);
 310 impl<T: Readable> Readable for RequiredWrapper<T> {
 311         #[inline]
 312         fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
 313                 Ok(Self(Some(Readable::read(reader)?)))
 314         }
 315 }
 316 impl<A, T: ReadableArgs<A>> ReadableArgs<A> for RequiredWrapper<T> {
 317         #[inline]
 318         fn read<R: Read>(reader: &mut R, args: A) -> Result<Self, DecodeError> {
 319                 Ok(Self(Some(ReadableArgs::read(reader, args)?)))
 320         }
 321 }
 322 /// When handling `default_values`, we want to map the default-value T directly
 323 /// to a `RequiredWrapper<T>` in a way that works for `field: T = t;` as
 324 /// well. Thus, we assume `Into<T> for T` does nothing and use that.
 325 impl<T> From<T> for RequiredWrapper<T> {
 326         fn from(t: T) -> RequiredWrapper<T> { RequiredWrapper(Some(t)) }
 327 }
 328
 329 /// Wrapper to read a required (non-optional) TLV record that may have been upgraded without
 330 /// backwards compat.
 331 ///
 332 /// This is not exported to bindings users as manual TLV building is not currently supported in bindings
 333 pub struct UpgradableRequired<T: MaybeReadable>(pub Option<T>);
 334 impl<T: MaybeReadable> MaybeReadable for UpgradableRequired<T> {
 335         #[inline]
 336         fn read<R: Read>(reader: &mut R) -> Result<Option<Self>, DecodeError> {
 337                 let tlv = MaybeReadable::read(reader)?;
 338                 if let Some(tlv) = tlv { return Ok(Some(Self(Some(tlv)))) }
 339                 Ok(None)
 340         }
 341 }
 342
 343 pub(crate) struct U48(pub u64);
 344 impl Writeable for U48 {
 345         #[inline]
 346         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 347                 writer.write_all(&be48_to_array(self.0))
 348         }
 349 }
 350 impl Readable for U48 {
 351         #[inline]
 352         fn read<R: Read>(reader: &mut R) -> Result<U48, DecodeError> {
 353                 let mut buf = [0; 6];
 354                 reader.read_exact(&mut buf)?;
 355                 Ok(U48(slice_to_be48(&buf)))
 356         }
 357 }
 358
 359 /// Lightning TLV uses a custom variable-length integer called `BigSize`. It is similar to Bitcoin's
 360 /// variable-length integers except that it is serialized in big-endian instead of little-endian.
 361 ///
 362 /// Like Bitcoin's variable-length integer, it exhibits ambiguity in that certain values can be
 363 /// encoded in several different ways, which we must check for at deserialization-time. Thus, if
 364 /// you're looking for an example of a variable-length integer to use for your own project, move
 365 /// along, this is a rather poor design.
 366 #[derive(Clone, Copy, Debug, Hash, PartialOrd, Ord, PartialEq, Eq)]
 367 pub struct BigSize(pub u64);
 368 impl Writeable for BigSize {
 369         #[inline]
 370         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 371                 match self.0 {
 372                         0..=0xFC => {
 373                                 (self.0 as u8).write(writer)
 374                         },
 375                         0xFD..=0xFFFF => {
 376                                 0xFDu8.write(writer)?;
 377                                 (self.0 as u16).write(writer)
 378                         },
 379                         0x10000..=0xFFFFFFFF => {
 380                                 0xFEu8.write(writer)?;
 381                                 (self.0 as u32).write(writer)
 382                         },
 383                         _ => {
 384                                 0xFFu8.write(writer)?;
 385                                 (self.0 as u64).write(writer)
 386                         },
 387                 }
 388         }
 389 }
 390 impl Readable for BigSize {
 391         #[inline]
 392         fn read<R: Read>(reader: &mut R) -> Result<BigSize, DecodeError> {
 393                 let n: u8 = Readable::read(reader)?;
 394                 match n {
 395                         0xFF => {
 396                                 let x: u64 = Readable::read(reader)?;
 397                                 if x < 0x100000000 {
 398                                         Err(DecodeError::InvalidValue)
 399                                 } else {
 400                                         Ok(BigSize(x))
 401                                 }
 402                         }
 403                         0xFE => {
 404                                 let x: u32 = Readable::read(reader)?;
 405                                 if x < 0x10000 {
 406                                         Err(DecodeError::InvalidValue)
 407                                 } else {
 408                                         Ok(BigSize(x as u64))
 409                                 }
 410                         }
 411                         0xFD => {
 412                                 let x: u16 = Readable::read(reader)?;
 413                                 if x < 0xFD {
 414                                         Err(DecodeError::InvalidValue)
 415                                 } else {
 416                                         Ok(BigSize(x as u64))
 417                                 }
 418                         }
 419                         n => Ok(BigSize(n as u64))
 420                 }
 421         }
 422 }
 423
 424 /// The lightning protocol uses u16s for lengths in most cases. As our serialization framework
 425 /// primarily targets that, we must as well. However, because we may serialize objects that have
 426 /// more than 65K entries, we need to be able to store larger values. Thus, we define a variable
 427 /// length integer here that is backwards-compatible for values < 0xffff. We treat 0xffff as
 428 /// "read eight more bytes".
 429 ///
 430 /// To ensure we only have one valid encoding per value, we add 0xffff to values written as eight
 431 /// bytes. Thus, 0xfffe is serialized as 0xfffe, whereas 0xffff is serialized as
 432 /// 0xffff0000000000000000 (i.e. read-eight-bytes then zero).
 433 struct CollectionLength(pub u64);
 434 impl Writeable for CollectionLength {
 435         #[inline]
 436         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 437                 if self.0 < 0xffff {
 438                         (self.0 as u16).write(writer)
 439                 } else {
 440                         0xffffu16.write(writer)?;
 441                         (self.0 - 0xffff).write(writer)
 442                 }
 443         }
 444 }
 445
 446 impl Readable for CollectionLength {
 447         #[inline]
 448         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 449                 let mut val: u64 = <u16 as Readable>::read(r)? as u64;
 450                 if val == 0xffff {
 451                         val = <u64 as Readable>::read(r)?
 452                                 .checked_add(0xffff).ok_or(DecodeError::InvalidValue)?;
 453                 }
 454                 Ok(CollectionLength(val))
 455         }
 456 }
 457
 458 /// In TLV we occasionally send fields which only consist of, or potentially end with, a
 459 /// variable-length integer which is simply truncated by skipping high zero bytes. This type
 460 /// encapsulates such integers implementing [`Readable`]/[`Writeable`] for them.
 461 #[cfg_attr(test, derive(PartialEq, Eq, Debug))]
 462 pub(crate) struct HighZeroBytesDroppedBigSize<T>(pub T);
 463
 464 macro_rules! impl_writeable_primitive {
 465         ($val_type:ty, $len: expr) => {
 466                 impl Writeable for $val_type {
 467                         #[inline]
 468                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 469                                 writer.write_all(&self.to_be_bytes())
 470                         }
 471                 }
 472                 impl Writeable for HighZeroBytesDroppedBigSize<$val_type> {
 473                         #[inline]
 474                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 475                                 // Skip any full leading 0 bytes when writing (in BE):
 476                                 writer.write_all(&self.0.to_be_bytes()[(self.0.leading_zeros()/8) as usize..$len])
 477                         }
 478                 }
 479                 impl Readable for $val_type {
 480                         #[inline]
 481                         fn read<R: Read>(reader: &mut R) -> Result<$val_type, DecodeError> {
 482                                 let mut buf = [0; $len];
 483                                 reader.read_exact(&mut buf)?;
 484                                 Ok(<$val_type>::from_be_bytes(buf))
 485                         }
 486                 }
 487                 impl Readable for HighZeroBytesDroppedBigSize<$val_type> {
 488                         #[inline]
 489                         fn read<R: Read>(reader: &mut R) -> Result<HighZeroBytesDroppedBigSize<$val_type>, DecodeError> {
 490                                 // We need to accept short reads (read_len == 0) as "EOF" and handle them as simply
 491                                 // the high bytes being dropped. To do so, we start reading into the middle of buf
 492                                 // and then convert the appropriate number of bytes with extra high bytes out of
 493                                 // buf.
 494                                 let mut buf = [0; $len*2];
 495                                 let mut read_len = reader.read(&mut buf[$len..])?;
 496                                 let mut total_read_len = read_len;
 497                                 while read_len != 0 && total_read_len != $len {
 498                                         read_len = reader.read(&mut buf[($len + total_read_len)..])?;
 499                                         total_read_len += read_len;
 500                                 }
 501                                 if total_read_len == 0 || buf[$len] != 0 {
 502                                         let first_byte = $len - ($len - total_read_len);
 503                                         let mut bytes = [0; $len];
 504                                         bytes.copy_from_slice(&buf[first_byte..first_byte + $len]);
 505                                         Ok(HighZeroBytesDroppedBigSize(<$val_type>::from_be_bytes(bytes)))
 506                                 } else {
 507                                         // If the encoding had extra zero bytes, return a failure even though we know
 508                                         // what they meant (as the TLV test vectors require this)
 509                                         Err(DecodeError::InvalidValue)
 510                                 }
 511                         }
 512                 }
 513                 impl From<$val_type> for HighZeroBytesDroppedBigSize<$val_type> {
 514                         fn from(val: $val_type) -> Self { Self(val) }
 515                 }
 516         }
 517 }
 518
 519 impl_writeable_primitive!(u128, 16);
 520 impl_writeable_primitive!(u64, 8);
 521 impl_writeable_primitive!(u32, 4);
 522 impl_writeable_primitive!(u16, 2);
 523 impl_writeable_primitive!(i64, 8);
 524 impl_writeable_primitive!(i32, 4);
 525 impl_writeable_primitive!(i16, 2);
 526 impl_writeable_primitive!(i8, 1);
 527
 528 impl Writeable for u8 {
 529         #[inline]
 530         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 531                 writer.write_all(&[*self])
 532         }
 533 }
 534 impl Readable for u8 {
 535         #[inline]
 536         fn read<R: Read>(reader: &mut R) -> Result<u8, DecodeError> {
 537                 let mut buf = [0; 1];
 538                 reader.read_exact(&mut buf)?;
 539                 Ok(buf[0])
 540         }
 541 }
 542
 543 impl Writeable for bool {
 544         #[inline]
 545         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 546                 writer.write_all(&[if *self {1} else {0}])
 547         }
 548 }
 549 impl Readable for bool {
 550         #[inline]
 551         fn read<R: Read>(reader: &mut R) -> Result<bool, DecodeError> {
 552                 let mut buf = [0; 1];
 553                 reader.read_exact(&mut buf)?;
 554                 if buf[0] != 0 && buf[0] != 1 {
 555                         return Err(DecodeError::InvalidValue);
 556                 }
 557                 Ok(buf[0] == 1)
 558         }
 559 }
 560
 561 macro_rules! impl_array {
 562         ($size:expr, $ty: ty) => (
 563                 impl Writeable for [$ty; $size] {
 564                         #[inline]
 565                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 566                                 let mut out = [0; $size * core::mem::size_of::<$ty>()];
 567                                 for (idx, v) in self.iter().enumerate() {
 568                                         let startpos = idx * core::mem::size_of::<$ty>();
 569                                         out[startpos..startpos + core::mem::size_of::<$ty>()].copy_from_slice(&v.to_be_bytes());
 570                                 }
 571                                 w.write_all(&out)
 572                         }
 573                 }
 574
 575                 impl Readable for [$ty; $size] {
 576                         #[inline]
 577                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 578                                 let mut buf = [0u8; $size * core::mem::size_of::<$ty>()];
 579                                 r.read_exact(&mut buf)?;
 580                                 let mut res = [0; $size];
 581                                 for (idx, v) in res.iter_mut().enumerate() {
 582                                         let startpos = idx * core::mem::size_of::<$ty>();
 583                                         let mut arr = [0; core::mem::size_of::<$ty>()];
 584                                         arr.copy_from_slice(&buf[startpos..startpos + core::mem::size_of::<$ty>()]);
 585                                         *v = <$ty>::from_be_bytes(arr);
 586                                 }
 587                                 Ok(res)
 588                         }
 589                 }
 590         );
 591 }
 592
 593 impl_array!(3, u8); // for rgb, ISO 4712 code
 594 impl_array!(4, u8); // for IPv4
 595 impl_array!(12, u8); // for OnionV2
 596 impl_array!(16, u8); // for IPv6
 597 impl_array!(32, u8); // for channel id & hmac
 598 impl_array!(PUBLIC_KEY_SIZE, u8); // for PublicKey
 599 impl_array!(64, u8); // for ecdsa::Signature and schnorr::Signature
 600 impl_array!(66, u8); // for MuSig2 nonces
 601 impl_array!(1300, u8); // for OnionPacket.hop_data
 602
 603 impl_array!(8, u16);
 604 impl_array!(32, u16);
 605
 606 /// A type for variable-length values within TLV record where the length is encoded as part of the record.
 607 /// Used to prevent encoding the length twice.
 608 ///
 609 /// This is not exported to bindings users as manual TLV building is not currently supported in bindings
 610 pub struct WithoutLength<T>(pub T);
 611
 612 impl Writeable for WithoutLength<&String> {
 613         #[inline]
 614         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 615                 w.write_all(self.0.as_bytes())
 616         }
 617 }
 618 impl Readable for WithoutLength<String> {
 619         #[inline]
 620         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 621                 let v: WithoutLength<Vec<u8>> = Readable::read(r)?;
 622                 Ok(Self(String::from_utf8(v.0).map_err(|_| DecodeError::InvalidValue)?))
 623         }
 624 }
 625 impl<'a> From<&'a String> for WithoutLength<&'a String> {
 626         fn from(s: &'a String) -> Self { Self(s) }
 627 }
 628
 629
 630 impl Writeable for WithoutLength<&UntrustedString> {
 631         #[inline]
 632         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 633                 WithoutLength(&self.0.0).write(w)
 634         }
 635 }
 636 impl Readable for WithoutLength<UntrustedString> {
 637         #[inline]
 638         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 639                 let s: WithoutLength<String> = Readable::read(r)?;
 640                 Ok(Self(UntrustedString(s.0)))
 641         }
 642 }
 643
 644 impl<'a, T: Writeable> Writeable for WithoutLength<&'a Vec<T>> {
 645         #[inline]
 646         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 647                 for ref v in self.0.iter() {
 648                         v.write(writer)?;
 649                 }
 650                 Ok(())
 651         }
 652 }
 653
 654 impl<T: MaybeReadable> Readable for WithoutLength<Vec<T>> {
 655         #[inline]
 656         fn read<R: Read>(mut reader: &mut R) -> Result<Self, DecodeError> {
 657                 let mut values = Vec::new();
 658                 loop {
 659                         let mut track_read = ReadTrackingReader::new(&mut reader);
 660                         match MaybeReadable::read(&mut track_read) {
 661                                 Ok(Some(v)) => { values.push(v); },
 662                                 Ok(None) => { },
 663                                 // If we failed to read any bytes at all, we reached the end of our TLV
 664                                 // stream and have simply exhausted all entries.
 665                                 Err(ref e) if e == &DecodeError::ShortRead && !track_read.have_read => break,
 666                                 Err(e) => return Err(e),
 667                         }
 668                 }
 669                 Ok(Self(values))
 670         }
 671 }
 672 impl<'a, T> From<&'a Vec<T>> for WithoutLength<&'a Vec<T>> {
 673         fn from(v: &'a Vec<T>) -> Self { Self(v) }
 674 }
 675
 676 impl Writeable for WithoutLength<&ScriptBuf> {
 677         #[inline]
 678         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 679                 writer.write_all(self.0.as_bytes())
 680         }
 681 }
 682
 683 impl Readable for WithoutLength<ScriptBuf> {
 684         #[inline]
 685         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 686                 let v: WithoutLength<Vec<u8>> = Readable::read(r)?;
 687                 Ok(WithoutLength(script::Builder::from(v.0).into_script()))
 688         }
 689 }
 690
 691 #[derive(Debug)]
 692 pub(crate) struct Iterable<'a, I: Iterator<Item = &'a T> + Clone, T: 'a>(pub I);
 693
 694 impl<'a, I: Iterator<Item = &'a T> + Clone, T: 'a + Writeable> Writeable for Iterable<'a, I, T> {
 695         #[inline]
 696         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 697                 for ref v in self.0.clone() {
 698                         v.write(writer)?;
 699                 }
 700                 Ok(())
 701         }
 702 }
 703
 704 #[cfg(test)]
 705 impl<'a, I: Iterator<Item = &'a T> + Clone, T: 'a + PartialEq> PartialEq for Iterable<'a, I, T> {
 706         fn eq(&self, other: &Self) -> bool {
 707                 self.0.clone().collect::<Vec<_>>() == other.0.clone().collect::<Vec<_>>()
 708         }
 709 }
 710
 711 macro_rules! impl_for_map {
 712         ($ty: ident, $keybound: ident, $constr: expr) => {
 713                 impl<K, V> Writeable for $ty<K, V>
 714                         where K: Writeable + Eq + $keybound, V: Writeable
 715                 {
 716                         #[inline]
 717                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 718                                 CollectionLength(self.len() as u64).write(w)?;
 719                                 for (key, value) in self.iter() {
 720                                         key.write(w)?;
 721                                         value.write(w)?;
 722                                 }
 723                                 Ok(())
 724                         }
 725                 }
 726
 727                 impl<K, V> Readable for $ty<K, V>
 728                         where K: Readable + Eq + $keybound, V: MaybeReadable
 729                 {
 730                         #[inline]
 731                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 732                                 let len: CollectionLength = Readable::read(r)?;
 733                                 let mut ret = $constr(len.0 as usize);
 734                                 for _ in 0..len.0 {
 735                                         let k = K::read(r)?;
 736                                         let v_opt = V::read(r)?;
 737                                         if let Some(v) = v_opt {
 738                                                 if ret.insert(k, v).is_some() {
 739                                                         return Err(DecodeError::InvalidValue);
 740                                                 }
 741                                         }
 742                                 }
 743                                 Ok(ret)
 744                         }
 745                 }
 746         }
 747 }
 748
 749 impl_for_map!(BTreeMap, Ord, |_| BTreeMap::new());
 750 impl_for_map!(HashMap, Hash, |len| hash_map_with_capacity(len));
 751
 752 // HashSet
 753 impl<T> Writeable for HashSet<T>
 754 where T: Writeable + Eq + Hash
 755 {
 756         #[inline]
 757         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 758                 CollectionLength(self.len() as u64).write(w)?;
 759                 for item in self.iter() {
 760                         item.write(w)?;
 761                 }
 762                 Ok(())
 763         }
 764 }
 765
 766 impl<T> Readable for HashSet<T>
 767 where T: Readable + Eq + Hash
 768 {
 769         #[inline]
 770         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 771                 let len: CollectionLength = Readable::read(r)?;
 772                 let mut ret = hash_set_with_capacity(cmp::min(len.0 as usize, MAX_BUF_SIZE / core::mem::size_of::<T>()));
 773                 for _ in 0..len.0 {
 774                         if !ret.insert(T::read(r)?) {
 775                                 return Err(DecodeError::InvalidValue)
 776                         }
 777                 }
 778                 Ok(ret)
 779         }
 780 }
 781
 782 // Vectors
 783 macro_rules! impl_writeable_for_vec {
 784         ($ty: ty $(, $name: ident)*) => {
 785                 impl<$($name : Writeable),*> Writeable for Vec<$ty> {
 786                         #[inline]
 787                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 788                                 CollectionLength(self.len() as u64).write(w)?;
 789                                 for elem in self.iter() {
 790                                         elem.write(w)?;
 791                                 }
 792                                 Ok(())
 793                         }
 794                 }
 795         }
 796 }
 797 macro_rules! impl_readable_for_vec {
 798         ($ty: ty $(, $name: ident)*) => {
 799                 impl<$($name : Readable),*> Readable for Vec<$ty> {
 800                         #[inline]
 801                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 802                                 let len: CollectionLength = Readable::read(r)?;
 803                                 let mut ret = Vec::with_capacity(cmp::min(len.0 as usize, MAX_BUF_SIZE / core::mem::size_of::<$ty>()));
 804                                 for _ in 0..len.0 {
 805                                         if let Some(val) = MaybeReadable::read(r)? {
 806                                                 ret.push(val);
 807                                         }
 808                                 }
 809                                 Ok(ret)
 810                         }
 811                 }
 812         }
 813 }
 814 macro_rules! impl_for_vec {
 815         ($ty: ty $(, $name: ident)*) => {
 816                 impl_writeable_for_vec!($ty $(, $name)*);
 817                 impl_readable_for_vec!($ty $(, $name)*);
 818         }
 819 }
 820
 821 // Alternatives to impl_writeable_for_vec/impl_readable_for_vec that add a length prefix to each
 822 // element in the Vec. Intended to be used when elements have variable lengths.
 823 macro_rules! impl_writeable_for_vec_with_element_length_prefix {
 824         ($ty: ty $(, $name: ident)*) => {
 825                 impl<$($name : Writeable),*> Writeable for Vec<$ty> {
 826                         #[inline]
 827                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 828                                 CollectionLength(self.len() as u64).write(w)?;
 829                                 for elem in self.iter() {
 830                                         CollectionLength(elem.serialized_length() as u64).write(w)?;
 831                                         elem.write(w)?;
 832                                 }
 833                                 Ok(())
 834                         }
 835                 }
 836         }
 837 }
 838 macro_rules! impl_readable_for_vec_with_element_length_prefix {
 839         ($ty: ty $(, $name: ident)*) => {
 840                 impl<$($name : Readable),*> Readable for Vec<$ty> {
 841                         #[inline]
 842                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 843                                 let len: CollectionLength = Readable::read(r)?;
 844                                 let mut ret = Vec::with_capacity(cmp::min(len.0 as usize, MAX_BUF_SIZE / core::mem::size_of::<$ty>()));
 845                                 for _ in 0..len.0 {
 846                                         let elem_len: CollectionLength = Readable::read(r)?;
 847                                         let mut elem_reader = FixedLengthReader::new(r, elem_len.0);
 848                                         if let Some(val) = MaybeReadable::read(&mut elem_reader)? {
 849                                                 ret.push(val);
 850                                         }
 851                                 }
 852                                 Ok(ret)
 853                         }
 854                 }
 855         }
 856 }
 857 macro_rules! impl_for_vec_with_element_length_prefix {
 858         ($ty: ty $(, $name: ident)*) => {
 859                 impl_writeable_for_vec_with_element_length_prefix!($ty $(, $name)*);
 860                 impl_readable_for_vec_with_element_length_prefix!($ty $(, $name)*);
 861         }
 862 }
 863
 864 impl Writeable for Vec<u8> {
 865         #[inline]
 866         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 867                 CollectionLength(self.len() as u64).write(w)?;
 868                 w.write_all(&self)
 869         }
 870 }
 871
 872 impl Readable for Vec<u8> {
 873         #[inline]
 874         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 875                 let mut len: CollectionLength = Readable::read(r)?;
 876                 let mut ret = Vec::new();
 877                 while len.0 > 0 {
 878                         let readamt = cmp::min(len.0 as usize, MAX_BUF_SIZE);
 879                         let readstart = ret.len();
 880                         ret.resize(readstart + readamt, 0);
 881                         r.read_exact(&mut ret[readstart..])?;
 882                         len.0 -= readamt as u64;
 883                 }
 884                 Ok(ret)
 885         }
 886 }
 887
 888 impl_for_vec!(ecdsa::Signature);
 889 impl_for_vec!(crate::chain::channelmonitor::ChannelMonitorUpdate);
 890 impl_for_vec!(crate::ln::channelmanager::MonitorUpdateCompletionAction);
 891 impl_for_vec!(crate::ln::msgs::SocketAddress);
 892 impl_for_vec!((A, B), A, B);
 893 impl_writeable_for_vec!(&crate::routing::router::BlindedTail);
 894 impl_readable_for_vec!(crate::routing::router::BlindedTail);
 895 impl_for_vec_with_element_length_prefix!(crate::ln::msgs::UpdateAddHTLC);
 896 impl_writeable_for_vec_with_element_length_prefix!(&crate::ln::msgs::UpdateAddHTLC);
 897
 898 impl Writeable for Vec<Witness> {
 899         #[inline]
 900         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 901                 (self.len() as u16).write(w)?;
 902                 for witness in self {
 903                         (witness.serialized_len() as u16).write(w)?;
 904                         witness.write(w)?;
 905                 }
 906                 Ok(())
 907         }
 908 }
 909
 910 impl Readable for Vec<Witness> {
 911         #[inline]
 912         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 913                 let num_witnesses = <u16 as Readable>::read(r)? as usize;
 914                 let mut witnesses = Vec::with_capacity(num_witnesses);
 915                 for _ in 0..num_witnesses {
 916                         // Even though the length of each witness can be inferred in its consensus-encoded form,
 917                         // the spec includes a length prefix so that implementations don't have to deserialize
 918                         //  each initially. We do that here anyway as in general we'll need to be able to make
 919                         // assertions on some properties of the witnesses when receiving a message providing a list
 920                         // of witnesses. We'll just do a sanity check for the lengths and error if there is a mismatch.
 921                         let witness_len = <u16 as Readable>::read(r)? as usize;
 922                         let witness = <Witness as Readable>::read(r)?;
 923                         if witness.serialized_len() != witness_len {
 924                                 return Err(DecodeError::BadLengthDescriptor);
 925                         }
 926                         witnesses.push(witness);
 927                 }
 928                 Ok(witnesses)
 929         }
 930 }
 931
 932 impl Writeable for ScriptBuf {
 933         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 934                 (self.len() as u16).write(w)?;
 935                 w.write_all(self.as_bytes())
 936         }
 937 }
 938
 939 impl Readable for ScriptBuf {
 940         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 941                 let len = <u16 as Readable>::read(r)? as usize;
 942                 let mut buf = vec![0; len];
 943                 r.read_exact(&mut buf)?;
 944                 Ok(ScriptBuf::from(buf))
 945         }
 946 }
 947
 948 impl Writeable for PublicKey {
 949         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 950                 self.serialize().write(w)
 951         }
 952         #[inline]
 953         fn serialized_length(&self) -> usize {
 954                 PUBLIC_KEY_SIZE
 955         }
 956 }
 957
 958 impl Readable for PublicKey {
 959         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 960                 let buf: [u8; PUBLIC_KEY_SIZE] = Readable::read(r)?;
 961                 match PublicKey::from_slice(&buf) {
 962                         Ok(key) => Ok(key),
 963                         Err(_) => return Err(DecodeError::InvalidValue),
 964                 }
 965         }
 966 }
 967
 968 impl Writeable for SecretKey {
 969         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 970                 let mut ser = [0; SECRET_KEY_SIZE];
 971                 ser.copy_from_slice(&self[..]);
 972                 ser.write(w)
 973         }
 974         #[inline]
 975         fn serialized_length(&self) -> usize {
 976                 SECRET_KEY_SIZE
 977         }
 978 }
 979
 980 impl Readable for SecretKey {
 981         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 982                 let buf: [u8; SECRET_KEY_SIZE] = Readable::read(r)?;
 983                 match SecretKey::from_slice(&buf) {
 984                         Ok(key) => Ok(key),
 985                         Err(_) => return Err(DecodeError::InvalidValue),
 986                 }
 987         }
 988 }
 989
 990 #[cfg(taproot)]
 991 impl Writeable for musig2::types::PublicNonce {
 992         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 993                 self.serialize().write(w)
 994         }
 995 }
 996
 997 #[cfg(taproot)]
 998 impl Readable for musig2::types::PublicNonce {
 999         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1000                 let buf: [u8; PUBLIC_KEY_SIZE * 2] = Readable::read(r)?;
1001                 musig2::types::PublicNonce::from_slice(&buf).map_err(|_| DecodeError::InvalidValue)
1002         }
1003 }
1004
1005 #[cfg(taproot)]
1006 impl Writeable for PartialSignatureWithNonce {
1007         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1008                 self.0.serialize().write(w)?;
1009                 self.1.write(w)
1010         }
1011 }
1012
1013 #[cfg(taproot)]
1014 impl Readable for PartialSignatureWithNonce {
1015         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1016                 let partial_signature_buf: [u8; SECRET_KEY_SIZE] = Readable::read(r)?;
1017                 let partial_signature = musig2::types::PartialSignature::from_slice(&partial_signature_buf).map_err(|_| DecodeError::InvalidValue)?;
1018                 let public_nonce: musig2::types::PublicNonce = Readable::read(r)?;
1019                 Ok(PartialSignatureWithNonce(partial_signature, public_nonce))
1020         }
1021 }
1022
1023 impl Writeable for Sha256dHash {
1024         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1025                 w.write_all(&self[..])
1026         }
1027 }
1028
1029 impl Readable for Sha256dHash {
1030         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1031                 use bitcoin::hashes::Hash;
1032
1033                 let buf: [u8; 32] = Readable::read(r)?;
1034                 Ok(Sha256dHash::from_slice(&buf[..]).unwrap())
1035         }
1036 }
1037
1038 impl Writeable for ecdsa::Signature {
1039         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1040                 self.serialize_compact().write(w)
1041         }
1042 }
1043
1044 impl Readable for ecdsa::Signature {
1045         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1046                 let buf: [u8; COMPACT_SIGNATURE_SIZE] = Readable::read(r)?;
1047                 match ecdsa::Signature::from_compact(&buf) {
1048                         Ok(sig) => Ok(sig),
1049                         Err(_) => return Err(DecodeError::InvalidValue),
1050                 }
1051         }
1052 }
1053
1054 impl Writeable for schnorr::Signature {
1055         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1056                 self.as_ref().write(w)
1057         }
1058 }
1059
1060 impl Readable for schnorr::Signature {
1061         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1062                 let buf: [u8; SCHNORR_SIGNATURE_SIZE] = Readable::read(r)?;
1063                 match schnorr::Signature::from_slice(&buf) {
1064                         Ok(sig) => Ok(sig),
1065                         Err(_) => return Err(DecodeError::InvalidValue),
1066                 }
1067         }
1068 }
1069
1070 impl Writeable for PaymentPreimage {
1071         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1072                 self.0.write(w)
1073         }
1074 }
1075
1076 impl Readable for PaymentPreimage {
1077         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1078                 let buf: [u8; 32] = Readable::read(r)?;
1079                 Ok(PaymentPreimage(buf))
1080         }
1081 }
1082
1083 impl Writeable for PaymentHash {
1084         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1085                 self.0.write(w)
1086         }
1087 }
1088
1089 impl Readable for PaymentHash {
1090         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1091                 let buf: [u8; 32] = Readable::read(r)?;
1092                 Ok(PaymentHash(buf))
1093         }
1094 }
1095
1096 impl Writeable for PaymentSecret {
1097         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1098                 self.0.write(w)
1099         }
1100 }
1101
1102 impl Readable for PaymentSecret {
1103         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1104                 let buf: [u8; 32] = Readable::read(r)?;
1105                 Ok(PaymentSecret(buf))
1106         }
1107 }
1108
1109 impl<T: Writeable> Writeable for Box<T> {
1110         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1111                 T::write(&**self, w)
1112         }
1113 }
1114
1115 impl<T: Readable> Readable for Box<T> {
1116         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1117                 Ok(Box::new(Readable::read(r)?))
1118         }
1119 }
1120
1121 impl<T: Writeable> Writeable for Option<T> {
1122         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1123                 match *self {
1124                         None => 0u8.write(w)?,
1125                         Some(ref data) => {
1126                                 BigSize(data.serialized_length() as u64 + 1).write(w)?;
1127                                 data.write(w)?;
1128                         }
1129                 }
1130                 Ok(())
1131         }
1132 }
1133
1134 impl<T: Readable> Readable for Option<T>
1135 {
1136         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1137                 let len: BigSize = Readable::read(r)?;
1138                 match len.0 {
1139                         0 => Ok(None),
1140                         len => {
1141                                 let mut reader = FixedLengthReader::new(r, len - 1);
1142                                 Ok(Some(Readable::read(&mut reader)?))
1143                         }
1144                 }
1145         }
1146 }
1147
1148 impl Writeable for Txid {
1149         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1150                 w.write_all(&self[..])
1151         }
1152 }
1153
1154 impl Readable for Txid {
1155         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1156                 use bitcoin::hashes::Hash;
1157
1158                 let buf: [u8; 32] = Readable::read(r)?;
1159                 Ok(Txid::from_slice(&buf[..]).unwrap())
1160         }
1161 }
1162
1163 impl Writeable for BlockHash {
1164         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1165                 w.write_all(&self[..])
1166         }
1167 }
1168
1169 impl Readable for BlockHash {
1170         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1171                 use bitcoin::hashes::Hash;
1172
1173                 let buf: [u8; 32] = Readable::read(r)?;
1174                 Ok(BlockHash::from_slice(&buf[..]).unwrap())
1175         }
1176 }
1177
1178 impl Writeable for ChainHash {
1179         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1180                 w.write_all(self.as_bytes())
1181         }
1182 }
1183
1184 impl Readable for ChainHash {
1185         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1186                 let buf: [u8; 32] = Readable::read(r)?;
1187                 Ok(ChainHash::from(buf))
1188         }
1189 }
1190
1191 impl Writeable for OutPoint {
1192         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1193                 self.txid.write(w)?;
1194                 self.vout.write(w)?;
1195                 Ok(())
1196         }
1197 }
1198
1199 impl Readable for OutPoint {
1200         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1201                 let txid = Readable::read(r)?;
1202                 let vout = Readable::read(r)?;
1203                 Ok(OutPoint {
1204                         txid,
1205                         vout,
1206                 })
1207         }
1208 }
1209
1210 macro_rules! impl_consensus_ser {
1211         ($bitcoin_type: ty) => {
1212                 impl Writeable for $bitcoin_type {
1213                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1214                                 match self.consensus_encode(&mut WriterWriteAdaptor(writer)) {
1215                                         Ok(_) => Ok(()),
1216                                         Err(e) => Err(e),
1217                                 }
1218                         }
1219                 }
1220
1221                 impl Readable for $bitcoin_type {
1222                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1223                                 match consensus::encode::Decodable::consensus_decode(r) {
1224                                         Ok(t) => Ok(t),
1225                                         Err(consensus::encode::Error::Io(ref e)) if e.kind() == io::ErrorKind::UnexpectedEof => Err(DecodeError::ShortRead),
1226                                         Err(consensus::encode::Error::Io(e)) => Err(DecodeError::Io(e.kind())),
1227                                         Err(_) => Err(DecodeError::InvalidValue),
1228                                 }
1229                         }
1230                 }
1231         }
1232 }
1233 impl_consensus_ser!(Transaction);
1234 impl_consensus_ser!(TxOut);
1235 impl_consensus_ser!(Witness);
1236
1237 impl<T: Readable> Readable for Mutex<T> {
1238         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1239                 let t: T = Readable::read(r)?;
1240                 Ok(Mutex::new(t))
1241         }
1242 }
1243 impl<T: Writeable> Writeable for Mutex<T> {
1244         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1245                 self.lock().unwrap().write(w)
1246         }
1247 }
1248
1249 impl<T: Readable> Readable for RwLock<T> {
1250         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1251                 let t: T = Readable::read(r)?;
1252                 Ok(RwLock::new(t))
1253         }
1254 }
1255 impl<T: Writeable> Writeable for RwLock<T> {
1256         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1257                 self.read().unwrap().write(w)
1258         }
1259 }
1260
1261 impl<A: Readable, B: Readable> Readable for (A, B) {
1262         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1263                 let a: A = Readable::read(r)?;
1264                 let b: B = Readable::read(r)?;
1265                 Ok((a, b))
1266         }
1267 }
1268 impl<A: Writeable, B: Writeable> Writeable for (A, B) {
1269         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1270                 self.0.write(w)?;
1271                 self.1.write(w)
1272         }
1273 }
1274
1275 impl<A: Readable, B: Readable, C: Readable> Readable for (A, B, C) {
1276         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1277                 let a: A = Readable::read(r)?;
1278                 let b: B = Readable::read(r)?;
1279                 let c: C = Readable::read(r)?;
1280                 Ok((a, b, c))
1281         }
1282 }
1283 impl<A: Writeable, B: Writeable, C: Writeable> Writeable for (A, B, C) {
1284         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1285                 self.0.write(w)?;
1286                 self.1.write(w)?;
1287                 self.2.write(w)
1288         }
1289 }
1290
1291 impl<A: Readable, B: Readable, C: Readable, D: Readable> Readable for (A, B, C, D) {
1292         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1293                 let a: A = Readable::read(r)?;
1294                 let b: B = Readable::read(r)?;
1295                 let c: C = Readable::read(r)?;
1296                 let d: D = Readable::read(r)?;
1297                 Ok((a, b, c, d))
1298         }
1299 }
1300 impl<A: Writeable, B: Writeable, C: Writeable, D: Writeable> Writeable for (A, B, C, D) {
1301         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1302                 self.0.write(w)?;
1303                 self.1.write(w)?;
1304                 self.2.write(w)?;
1305                 self.3.write(w)
1306         }
1307 }
1308
1309 impl Writeable for () {
1310         fn write<W: Writer>(&self, _: &mut W) -> Result<(), io::Error> {
1311                 Ok(())
1312         }
1313 }
1314 impl Readable for () {
1315         fn read<R: Read>(_r: &mut R) -> Result<Self, DecodeError> {
1316                 Ok(())
1317         }
1318 }
1319
1320 impl Writeable for String {
1321         #[inline]
1322         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1323                 CollectionLength(self.len() as u64).write(w)?;
1324                 w.write_all(self.as_bytes())
1325         }
1326 }
1327 impl Readable for String {
1328         #[inline]
1329         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1330                 let v: Vec<u8> = Readable::read(r)?;
1331                 let ret = String::from_utf8(v).map_err(|_| DecodeError::InvalidValue)?;
1332                 Ok(ret)
1333         }
1334 }
1335
1336 /// Represents a hostname for serialization purposes.
1337 /// Only the character set and length will be validated.
1338 /// The character set consists of ASCII alphanumeric characters, hyphens, and periods.
1339 /// Its length is guaranteed to be representable by a single byte.
1340 /// This serialization is used by [`BOLT 7`] hostnames.
1341 ///
1342 /// [`BOLT 7`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md
1343 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
1344 pub struct Hostname(String);
1345 impl Hostname {
1346         /// Returns the length of the hostname.
1347         pub fn len(&self) -> u8 {
1348                 (&self.0).len() as u8
1349         }
1350 }
1351
1352 impl core::fmt::Display for Hostname {
1353         fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
1354                 write!(f, "{}", self.0)?;
1355                 Ok(())
1356         }
1357 }
1358 impl Deref for Hostname {
1359         type Target = String;
1360
1361         fn deref(&self) -> &Self::Target {
1362                 &self.0
1363         }
1364 }
1365 impl From<Hostname> for String {
1366         fn from(hostname: Hostname) -> Self {
1367                 hostname.0
1368         }
1369 }
1370 impl TryFrom<Vec<u8>> for Hostname {
1371         type Error = ();
1372
1373         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1374                 if let Ok(s) = String::from_utf8(bytes) {
1375                         Hostname::try_from(s)
1376                 } else {
1377                         Err(())
1378                 }
1379         }
1380 }
1381 impl TryFrom<String> for Hostname {
1382         type Error = ();
1383
1384         fn try_from(s: String) -> Result<Self, Self::Error> {
1385                 if s.len() <= 255 && s.chars().all(|c|
1386                         c.is_ascii_alphanumeric() ||
1387                         c == '.' ||
1388                         c == '-'
1389                 ) {
1390                         Ok(Hostname(s))
1391                 } else {
1392                         Err(())
1393                 }
1394         }
1395 }
1396 impl Writeable for Hostname {
1397         #[inline]
1398         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1399                 self.len().write(w)?;
1400                 w.write_all(self.as_bytes())
1401         }
1402 }
1403 impl Readable for Hostname {
1404         #[inline]
1405         fn read<R: Read>(r: &mut R) -> Result<Hostname, DecodeError> {
1406                 let len: u8 = Readable::read(r)?;
1407                 let mut vec = Vec::with_capacity(len.into());
1408                 vec.resize(len.into(), 0);
1409                 r.read_exact(&mut vec)?;
1410                 Hostname::try_from(vec).map_err(|_| DecodeError::InvalidValue)
1411         }
1412 }
1413
1414 /// This is not exported to bindings users as `Duration`s are simply mapped as ints.
1415 impl Writeable for Duration {
1416         #[inline]
1417         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1418                 self.as_secs().write(w)?;
1419                 self.subsec_nanos().write(w)
1420         }
1421 }
1422 /// This is not exported to bindings users as `Duration`s are simply mapped as ints.
1423 impl Readable for Duration {
1424         #[inline]
1425         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1426                 let secs = Readable::read(r)?;
1427                 let nanos = Readable::read(r)?;
1428                 Ok(Duration::new(secs, nanos))
1429         }
1430 }
1431
1432 /// A wrapper for a `Transaction` which can only be constructed with [`TransactionU16LenLimited::new`]
1433 /// if the `Transaction`'s consensus-serialized length is <= u16::MAX.
1434 ///
1435 /// Use [`TransactionU16LenLimited::into_transaction`] to convert into the contained `Transaction`.
1436 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
1437 pub struct TransactionU16LenLimited(Transaction);
1438
1439 impl TransactionU16LenLimited {
1440         /// Constructs a new `TransactionU16LenLimited` from a `Transaction` only if it's consensus-
1441         /// serialized length is <= u16::MAX.
1442         pub fn new(transaction: Transaction) -> Result<Self, ()> {
1443                 if transaction.serialized_length() > (u16::MAX as usize) {
1444                         Err(())
1445                 } else {
1446                         Ok(Self(transaction))
1447                 }
1448         }
1449
1450         /// Consumes this `TransactionU16LenLimited` and returns its contained `Transaction`.
1451         pub fn into_transaction(self) -> Transaction {
1452                 self.0
1453         }
1454
1455         /// Returns a reference to the contained `Transaction`
1456         pub fn as_transaction(&self) -> &Transaction {
1457                 &self.0
1458         }
1459 }
1460
1461 impl Writeable for TransactionU16LenLimited {
1462         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1463                 (self.0.serialized_length() as u16).write(w)?;
1464                 self.0.write(w)
1465         }
1466 }
1467
1468 impl Readable for TransactionU16LenLimited {
1469         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1470                 let len = <u16 as Readable>::read(r)?;
1471                 let mut tx_reader = FixedLengthReader::new(r, len as u64);
1472                 let tx: Transaction = Readable::read(&mut tx_reader)?;
1473                 if tx_reader.bytes_remain() {
1474                         Err(DecodeError::BadLengthDescriptor)
1475                 } else {
1476                         Ok(Self(tx))
1477                 }
1478         }
1479 }
1480
1481 impl Writeable for ClaimId {
1482         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1483                 self.0.write(writer)
1484         }
1485 }
1486
1487 impl Readable for ClaimId {
1488         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
1489                 Ok(Self(Readable::read(reader)?))
1490         }
1491 }
1492
1493 #[cfg(test)]
1494 mod tests {
1495         use bitcoin::hashes::hex::FromHex;
1496         use bitcoin::secp256k1::ecdsa;
1497         use crate::util::ser::{Readable, Hostname, Writeable};
1498         use crate::prelude::*;
1499
1500         #[test]
1501         fn hostname_conversion() {
1502                 assert_eq!(Hostname::try_from(String::from("a-test.com")).unwrap().as_str(), "a-test.com");
1503
1504                 assert!(Hostname::try_from(String::from("\"")).is_err());
1505                 assert!(Hostname::try_from(String::from("$")).is_err());
1506                 assert!(Hostname::try_from(String::from("⚡")).is_err());
1507                 let mut large_vec = Vec::with_capacity(256);
1508                 large_vec.resize(256, b'A');
1509                 assert!(Hostname::try_from(String::from_utf8(large_vec).unwrap()).is_err());
1510         }
1511
1512         #[test]
1513         fn hostname_serialization() {
1514                 let hostname = Hostname::try_from(String::from("test")).unwrap();
1515                 let mut buf: Vec<u8> = Vec::new();
1516                 hostname.write(&mut buf).unwrap();
1517                 assert_eq!(Hostname::read(&mut buf.as_slice()).unwrap().as_str(), "test");
1518         }
1519
1520         #[test]
1521         /// Taproot will likely fill legacy signature fields with all 0s.
1522         /// This test ensures that doing so won't break serialization.
1523         fn null_signature_codec() {
1524                 let buffer = vec![0u8; 64];
1525                 let mut cursor = crate::io::Cursor::new(buffer.clone());
1526                 let signature = ecdsa::Signature::read(&mut cursor).unwrap();
1527                 let serialization = signature.serialize_compact();
1528                 assert_eq!(buffer, serialization.to_vec())
1529         }
1530
1531         #[test]
1532         fn bigsize_encoding_decoding() {
1533                 let values = vec![0, 252, 253, 65535, 65536, 4294967295, 4294967296, 18446744073709551615];
1534                 let bytes = vec![
1535                         "00",
1536                         "fc",
1537                         "fd00fd",
1538                         "fdffff",
1539                         "fe00010000",
1540                         "feffffffff",
1541                         "ff0000000100000000",
1542                         "ffffffffffffffffff"
1543                 ];
1544                 for i in 0..=7 {
1545                         let mut stream = crate::io::Cursor::new(<Vec<u8>>::from_hex(bytes[i]).unwrap());
1546                         assert_eq!(super::BigSize::read(&mut stream).unwrap().0, values[i]);
1547                         let mut stream = super::VecWriter(Vec::new());
1548                         super::BigSize(values[i]).write(&mut stream).unwrap();
1549                         assert_eq!(stream.0, <Vec<u8>>::from_hex(bytes[i]).unwrap());
1550                 }
1551                 let err_bytes = vec![
1552                         "fd00fc",
1553                         "fe0000ffff",
1554                         "ff00000000ffffffff",
1555                         "fd00",
1556                         "feffff",
1557                         "ffffffffff",
1558                         "fd",
1559                         "fe",
1560                         "ff",
1561                         ""
1562                 ];
1563                 for i in 0..=9 {
1564                         let mut stream = crate::io::Cursor::new(<Vec<u8>>::from_hex(err_bytes[i]).unwrap());
1565                         if i < 3 {
1566                                 assert_eq!(super::BigSize::read(&mut stream).err(), Some(crate::ln::msgs::DecodeError::InvalidValue));
1567                         } else {
1568                                 assert_eq!(super::BigSize::read(&mut stream).err(), Some(crate::ln::msgs::DecodeError::ShortRead));
1569                         }
1570                 }
1571         }
1572 }