_ 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::Script;
  33 use bitcoin::blockdata::transaction::{OutPoint, Transaction, TxOut};
  34 use bitcoin::consensus;
  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 use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
  42
  43 use crate::util::byte_utils::{be48_to_array, slice_to_be48};
  44
  45 /// serialization buffer size
  46 pub const MAX_BUF_SIZE: usize = 64 * 1024;
  47
  48 /// A simplified version of [`std::io::Write`] that exists largely for backwards compatibility.
  49 /// An impl is provided for any type that also impls [`std::io::Write`].
  50 ///
  51 /// (C-not exported) as we only export serialization to/from byte arrays instead
  52 pub trait Writer {
  53         /// Writes the given buf out. See std::io::Write::write_all for more
  54         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error>;
  55 }
  56
  57 impl<W: Write> Writer for W {
  58         #[inline]
  59         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  60                 <Self as io::Write>::write_all(self, buf)
  61         }
  62 }
  63
  64 pub(crate) struct WriterWriteAdaptor<'a, W: Writer + 'a>(pub &'a mut W);
  65 impl<'a, W: Writer + 'a> Write for WriterWriteAdaptor<'a, W> {
  66         #[inline]
  67         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  68                 self.0.write_all(buf)
  69         }
  70         #[inline]
  71         fn write(&mut self, buf: &[u8]) -> Result<usize, io::Error> {
  72                 self.0.write_all(buf)?;
  73                 Ok(buf.len())
  74         }
  75         #[inline]
  76         fn flush(&mut self) -> Result<(), io::Error> {
  77                 Ok(())
  78         }
  79 }
  80
  81 pub(crate) struct VecWriter(pub Vec<u8>);
  82 impl Writer for VecWriter {
  83         #[inline]
  84         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  85                 self.0.extend_from_slice(buf);
  86                 Ok(())
  87         }
  88 }
  89
  90 /// Writer that only tracks the amount of data written - useful if you need to calculate the length
  91 /// of some data when serialized but don't yet need the full data.
  92 pub struct LengthCalculatingWriter(pub usize);
  93 impl Writer for LengthCalculatingWriter {
  94         #[inline]
  95         fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
  96                 self.0 += buf.len();
  97                 Ok(())
  98         }
  99 }
 100
 101 /// Essentially [`std::io::Take`] but a bit simpler and with a method to walk the underlying stream
 102 /// forward to ensure we always consume exactly the fixed length specified.
 103 pub struct FixedLengthReader<R: Read> {
 104         read: R,
 105         bytes_read: u64,
 106         total_bytes: u64,
 107 }
 108 impl<R: Read> FixedLengthReader<R> {
 109         /// Returns a new [`FixedLengthReader`].
 110         pub fn new(read: R, total_bytes: u64) -> Self {
 111                 Self { read, bytes_read: 0, total_bytes }
 112         }
 113
 114         /// Returns whether some bytes are remaining or not.
 115         #[inline]
 116         pub fn bytes_remain(&mut self) -> bool {
 117                 self.bytes_read != self.total_bytes
 118         }
 119
 120         /// Consumes the remaining bytes.
 121         #[inline]
 122         pub fn eat_remaining(&mut self) -> Result<(), DecodeError> {
 123                 copy(self, &mut sink()).unwrap();
 124                 if self.bytes_read != self.total_bytes {
 125                         Err(DecodeError::ShortRead)
 126                 } else {
 127                         Ok(())
 128                 }
 129         }
 130 }
 131 impl<R: Read> Read for FixedLengthReader<R> {
 132         #[inline]
 133         fn read(&mut self, dest: &mut [u8]) -> Result<usize, io::Error> {
 134                 if self.total_bytes == self.bytes_read {
 135                         Ok(0)
 136                 } else {
 137                         let read_len = cmp::min(dest.len() as u64, self.total_bytes - self.bytes_read);
 138                         match self.read.read(&mut dest[0..(read_len as usize)]) {
 139                                 Ok(v) => {
 140                                         self.bytes_read += v as u64;
 141                                         Ok(v)
 142                                 },
 143                                 Err(e) => Err(e),
 144                         }
 145                 }
 146         }
 147 }
 148
 149 impl<R: Read> LengthRead for FixedLengthReader<R> {
 150         #[inline]
 151         fn total_bytes(&self) -> u64 {
 152                 self.total_bytes
 153         }
 154 }
 155
 156 /// A [`Read`] implementation which tracks whether any bytes have been read at all. This allows us to distinguish
 157 /// between "EOF reached before we started" and "EOF reached mid-read".
 158 pub struct ReadTrackingReader<R: Read> {
 159         read: R,
 160         /// Returns whether we have read from this reader or not yet.
 161         pub have_read: bool,
 162 }
 163 impl<R: Read> ReadTrackingReader<R> {
 164         /// Returns a new [`ReadTrackingReader`].
 165         pub fn new(read: R) -> Self {
 166                 Self { read, have_read: false }
 167         }
 168 }
 169 impl<R: Read> Read for ReadTrackingReader<R> {
 170         #[inline]
 171         fn read(&mut self, dest: &mut [u8]) -> Result<usize, io::Error> {
 172                 match self.read.read(dest) {
 173                         Ok(0) => Ok(0),
 174                         Ok(len) => {
 175                                 self.have_read = true;
 176                                 Ok(len)
 177                         },
 178                         Err(e) => Err(e),
 179                 }
 180         }
 181 }
 182
 183 /// A trait that various LDK types implement allowing them to be written out to a [`Writer`].
 184 ///
 185 /// (C-not exported) as we only export serialization to/from byte arrays instead
 186 pub trait Writeable {
 187         /// Writes `self` out to the given [`Writer`].
 188         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error>;
 189
 190         /// Writes `self` out to a `Vec<u8>`.
 191         fn encode(&self) -> Vec<u8> {
 192                 let mut msg = VecWriter(Vec::new());
 193                 self.write(&mut msg).unwrap();
 194                 msg.0
 195         }
 196
 197         /// Writes `self` out to a `Vec<u8>`.
 198         #[cfg(test)]
 199         fn encode_with_len(&self) -> Vec<u8> {
 200                 let mut msg = VecWriter(Vec::new());
 201                 0u16.write(&mut msg).unwrap();
 202                 self.write(&mut msg).unwrap();
 203                 let len = msg.0.len();
 204                 msg.0[..2].copy_from_slice(&(len as u16 - 2).to_be_bytes());
 205                 msg.0
 206         }
 207
 208         /// Gets the length of this object after it has been serialized. This can be overridden to
 209         /// optimize cases where we prepend an object with its length.
 210         // Note that LLVM optimizes this away in most cases! Check that it isn't before you override!
 211         #[inline]
 212         fn serialized_length(&self) -> usize {
 213                 let mut len_calc = LengthCalculatingWriter(0);
 214                 self.write(&mut len_calc).expect("No in-memory data may fail to serialize");
 215                 len_calc.0
 216         }
 217 }
 218
 219 impl<'a, T: Writeable> Writeable for &'a T {
 220         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { (*self).write(writer) }
 221 }
 222
 223 /// A trait that various LDK types implement allowing them to be read in from a [`Read`].
 224 ///
 225 /// (C-not exported) as we only export serialization to/from byte arrays instead
 226 pub trait Readable
 227         where Self: Sized
 228 {
 229         /// Reads a `Self` in from the given [`Read`].
 230         fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError>;
 231 }
 232
 233 /// A trait that various LDK types implement allowing them to be read in from a
 234 /// [`Read`]` + `[`Seek`].
 235 pub(crate) trait SeekReadable where Self: Sized {
 236         /// Reads a `Self` in from the given [`Read`].
 237         fn read<R: Read + Seek>(reader: &mut R) -> Result<Self, DecodeError>;
 238 }
 239
 240 /// A trait that various higher-level LDK types implement allowing them to be read in
 241 /// from a [`Read`] given some additional set of arguments which is required to deserialize.
 242 ///
 243 /// (C-not exported) as we only export serialization to/from byte arrays instead
 244 pub trait ReadableArgs<P>
 245         where Self: Sized
 246 {
 247         /// Reads a `Self` in from the given [`Read`].
 248         fn read<R: Read>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 249 }
 250
 251 /// A [`std::io::Read`] that also provides the total bytes available to be read.
 252 pub(crate) trait LengthRead: Read {
 253         /// The total number of bytes available to be read.
 254         fn total_bytes(&self) -> u64;
 255 }
 256
 257 /// A trait that various higher-level LDK types implement allowing them to be read in
 258 /// from a Read given some additional set of arguments which is required to deserialize, requiring
 259 /// the implementer to provide the total length of the read.
 260 pub(crate) trait LengthReadableArgs<P> where Self: Sized
 261 {
 262         /// Reads a `Self` in from the given [`LengthRead`].
 263         fn read<R: LengthRead>(reader: &mut R, params: P) -> Result<Self, DecodeError>;
 264 }
 265
 266 /// A trait that various higher-level LDK types implement allowing them to be read in
 267 /// from a [`Read`], requiring the implementer to provide the total length of the read.
 268 pub(crate) trait LengthReadable where Self: Sized
 269 {
 270         /// Reads a `Self` in from the given [`LengthRead`].
 271         fn read<R: LengthRead>(reader: &mut R) -> Result<Self, DecodeError>;
 272 }
 273
 274 /// A trait that various LDK types implement allowing them to (maybe) be read in from a [`Read`].
 275 ///
 276 /// (C-not exported) as we only export serialization to/from byte arrays instead
 277 pub trait MaybeReadable
 278         where Self: Sized
 279 {
 280         /// Reads a `Self` in from the given [`Read`].
 281         fn read<R: Read>(reader: &mut R) -> Result<Option<Self>, DecodeError>;
 282 }
 283
 284 impl<T: Readable> MaybeReadable for T {
 285         #[inline]
 286         fn read<R: Read>(reader: &mut R) -> Result<Option<T>, DecodeError> {
 287                 Ok(Some(Readable::read(reader)?))
 288         }
 289 }
 290
 291 /// Wrapper to read a required (non-optional) TLV record.
 292 pub struct OptionDeserWrapper<T: Readable>(pub Option<T>);
 293 impl<T: Readable> Readable for OptionDeserWrapper<T> {
 294         #[inline]
 295         fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
 296                 Ok(Self(Some(Readable::read(reader)?)))
 297         }
 298 }
 299 /// When handling `default_values`, we want to map the default-value T directly
 300 /// to a `OptionDeserWrapper<T>` in a way that works for `field: T = t;` as
 301 /// well. Thus, we assume `Into<T> for T` does nothing and use that.
 302 impl<T: Readable> From<T> for OptionDeserWrapper<T> {
 303         fn from(t: T) -> OptionDeserWrapper<T> { OptionDeserWrapper(Some(t)) }
 304 }
 305
 306 pub(crate) struct U48(pub u64);
 307 impl Writeable for U48 {
 308         #[inline]
 309         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 310                 writer.write_all(&be48_to_array(self.0))
 311         }
 312 }
 313 impl Readable for U48 {
 314         #[inline]
 315         fn read<R: Read>(reader: &mut R) -> Result<U48, DecodeError> {
 316                 let mut buf = [0; 6];
 317                 reader.read_exact(&mut buf)?;
 318                 Ok(U48(slice_to_be48(&buf)))
 319         }
 320 }
 321
 322 /// Lightning TLV uses a custom variable-length integer called `BigSize`. It is similar to Bitcoin's
 323 /// variable-length integers except that it is serialized in big-endian instead of little-endian.
 324 ///
 325 /// Like Bitcoin's variable-length integer, it exhibits ambiguity in that certain values can be
 326 /// encoded in several different ways, which we must check for at deserialization-time. Thus, if
 327 /// you're looking for an example of a variable-length integer to use for your own project, move
 328 /// along, this is a rather poor design.
 329 pub struct BigSize(pub u64);
 330 impl Writeable for BigSize {
 331         #[inline]
 332         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 333                 match self.0 {
 334                         0...0xFC => {
 335                                 (self.0 as u8).write(writer)
 336                         },
 337                         0xFD...0xFFFF => {
 338                                 0xFDu8.write(writer)?;
 339                                 (self.0 as u16).write(writer)
 340                         },
 341                         0x10000...0xFFFFFFFF => {
 342                                 0xFEu8.write(writer)?;
 343                                 (self.0 as u32).write(writer)
 344                         },
 345                         _ => {
 346                                 0xFFu8.write(writer)?;
 347                                 (self.0 as u64).write(writer)
 348                         },
 349                 }
 350         }
 351 }
 352 impl Readable for BigSize {
 353         #[inline]
 354         fn read<R: Read>(reader: &mut R) -> Result<BigSize, DecodeError> {
 355                 let n: u8 = Readable::read(reader)?;
 356                 match n {
 357                         0xFF => {
 358                                 let x: u64 = Readable::read(reader)?;
 359                                 if x < 0x100000000 {
 360                                         Err(DecodeError::InvalidValue)
 361                                 } else {
 362                                         Ok(BigSize(x))
 363                                 }
 364                         }
 365                         0xFE => {
 366                                 let x: u32 = Readable::read(reader)?;
 367                                 if x < 0x10000 {
 368                                         Err(DecodeError::InvalidValue)
 369                                 } else {
 370                                         Ok(BigSize(x as u64))
 371                                 }
 372                         }
 373                         0xFD => {
 374                                 let x: u16 = Readable::read(reader)?;
 375                                 if x < 0xFD {
 376                                         Err(DecodeError::InvalidValue)
 377                                 } else {
 378                                         Ok(BigSize(x as u64))
 379                                 }
 380                         }
 381                         n => Ok(BigSize(n as u64))
 382                 }
 383         }
 384 }
 385
 386 /// In TLV we occasionally send fields which only consist of, or potentially end with, a
 387 /// variable-length integer which is simply truncated by skipping high zero bytes. This type
 388 /// encapsulates such integers implementing [`Readable`]/[`Writeable`] for them.
 389 #[cfg_attr(test, derive(PartialEq, Eq, Debug))]
 390 pub(crate) struct HighZeroBytesDroppedBigSize<T>(pub T);
 391
 392 macro_rules! impl_writeable_primitive {
 393         ($val_type:ty, $len: expr) => {
 394                 impl Writeable for $val_type {
 395                         #[inline]
 396                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 397                                 writer.write_all(&self.to_be_bytes())
 398                         }
 399                 }
 400                 impl Writeable for HighZeroBytesDroppedBigSize<$val_type> {
 401                         #[inline]
 402                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 403                                 // Skip any full leading 0 bytes when writing (in BE):
 404                                 writer.write_all(&self.0.to_be_bytes()[(self.0.leading_zeros()/8) as usize..$len])
 405                         }
 406                 }
 407                 impl Readable for $val_type {
 408                         #[inline]
 409                         fn read<R: Read>(reader: &mut R) -> Result<$val_type, DecodeError> {
 410                                 let mut buf = [0; $len];
 411                                 reader.read_exact(&mut buf)?;
 412                                 Ok(<$val_type>::from_be_bytes(buf))
 413                         }
 414                 }
 415                 impl Readable for HighZeroBytesDroppedBigSize<$val_type> {
 416                         #[inline]
 417                         fn read<R: Read>(reader: &mut R) -> Result<HighZeroBytesDroppedBigSize<$val_type>, DecodeError> {
 418                                 // We need to accept short reads (read_len == 0) as "EOF" and handle them as simply
 419                                 // the high bytes being dropped. To do so, we start reading into the middle of buf
 420                                 // and then convert the appropriate number of bytes with extra high bytes out of
 421                                 // buf.
 422                                 let mut buf = [0; $len*2];
 423                                 let mut read_len = reader.read(&mut buf[$len..])?;
 424                                 let mut total_read_len = read_len;
 425                                 while read_len != 0 && total_read_len != $len {
 426                                         read_len = reader.read(&mut buf[($len + total_read_len)..])?;
 427                                         total_read_len += read_len;
 428                                 }
 429                                 if total_read_len == 0 || buf[$len] != 0 {
 430                                         let first_byte = $len - ($len - total_read_len);
 431                                         let mut bytes = [0; $len];
 432                                         bytes.copy_from_slice(&buf[first_byte..first_byte + $len]);
 433                                         Ok(HighZeroBytesDroppedBigSize(<$val_type>::from_be_bytes(bytes)))
 434                                 } else {
 435                                         // If the encoding had extra zero bytes, return a failure even though we know
 436                                         // what they meant (as the TLV test vectors require this)
 437                                         Err(DecodeError::InvalidValue)
 438                                 }
 439                         }
 440                 }
 441                 impl From<$val_type> for HighZeroBytesDroppedBigSize<$val_type> {
 442                         fn from(val: $val_type) -> Self { Self(val) }
 443                 }
 444         }
 445 }
 446
 447 impl_writeable_primitive!(u128, 16);
 448 impl_writeable_primitive!(u64, 8);
 449 impl_writeable_primitive!(u32, 4);
 450 impl_writeable_primitive!(u16, 2);
 451
 452 impl Writeable for u8 {
 453         #[inline]
 454         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 455                 writer.write_all(&[*self])
 456         }
 457 }
 458 impl Readable for u8 {
 459         #[inline]
 460         fn read<R: Read>(reader: &mut R) -> Result<u8, DecodeError> {
 461                 let mut buf = [0; 1];
 462                 reader.read_exact(&mut buf)?;
 463                 Ok(buf[0])
 464         }
 465 }
 466
 467 impl Writeable for bool {
 468         #[inline]
 469         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 470                 writer.write_all(&[if *self {1} else {0}])
 471         }
 472 }
 473 impl Readable for bool {
 474         #[inline]
 475         fn read<R: Read>(reader: &mut R) -> Result<bool, DecodeError> {
 476                 let mut buf = [0; 1];
 477                 reader.read_exact(&mut buf)?;
 478                 if buf[0] != 0 && buf[0] != 1 {
 479                         return Err(DecodeError::InvalidValue);
 480                 }
 481                 Ok(buf[0] == 1)
 482         }
 483 }
 484
 485 // u8 arrays
 486 macro_rules! impl_array {
 487         ( $size:expr ) => (
 488                 impl Writeable for [u8; $size]
 489                 {
 490                         #[inline]
 491                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 492                                 w.write_all(self)
 493                         }
 494                 }
 495
 496                 impl Readable for [u8; $size]
 497                 {
 498                         #[inline]
 499                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 500                                 let mut buf = [0u8; $size];
 501                                 r.read_exact(&mut buf)?;
 502                                 Ok(buf)
 503                         }
 504                 }
 505         );
 506 }
 507
 508 impl_array!(3); // for rgb, ISO 4712 code
 509 impl_array!(4); // for IPv4
 510 impl_array!(12); // for OnionV2
 511 impl_array!(16); // for IPv6
 512 impl_array!(32); // for channel id & hmac
 513 impl_array!(PUBLIC_KEY_SIZE); // for PublicKey
 514 impl_array!(64); // for ecdsa::Signature and schnorr::Signature
 515 impl_array!(1300); // for OnionPacket.hop_data
 516
 517 impl Writeable for [u16; 8] {
 518         #[inline]
 519         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 520                 for v in self.iter() {
 521                         w.write_all(&v.to_be_bytes())?
 522                 }
 523                 Ok(())
 524         }
 525 }
 526
 527 impl Readable for [u16; 8] {
 528         #[inline]
 529         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 530                 let mut buf = [0u8; 16];
 531                 r.read_exact(&mut buf)?;
 532                 let mut res = [0u16; 8];
 533                 for (idx, v) in res.iter_mut().enumerate() {
 534                         *v = (buf[idx] as u16) << 8 | (buf[idx + 1] as u16)
 535                 }
 536                 Ok(res)
 537         }
 538 }
 539
 540 /// A type for variable-length values within TLV record where the length is encoded as part of the record.
 541 /// Used to prevent encoding the length twice.
 542 pub struct WithoutLength<T>(pub T);
 543
 544 impl Writeable for WithoutLength<&String> {
 545         #[inline]
 546         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 547                 w.write_all(self.0.as_bytes())
 548         }
 549 }
 550 impl Readable for WithoutLength<String> {
 551         #[inline]
 552         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 553                 let v: WithoutLength<Vec<u8>> = Readable::read(r)?;
 554                 Ok(Self(String::from_utf8(v.0).map_err(|_| DecodeError::InvalidValue)?))
 555         }
 556 }
 557 impl<'a> From<&'a String> for WithoutLength<&'a String> {
 558         fn from(s: &'a String) -> Self { Self(s) }
 559 }
 560
 561 impl<'a, T: Writeable> Writeable for WithoutLength<&'a Vec<T>> {
 562         #[inline]
 563         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 564                 for ref v in self.0.iter() {
 565                         v.write(writer)?;
 566                 }
 567                 Ok(())
 568         }
 569 }
 570
 571 impl<T: MaybeReadable> Readable for WithoutLength<Vec<T>> {
 572         #[inline]
 573         fn read<R: Read>(mut reader: &mut R) -> Result<Self, DecodeError> {
 574                 let mut values = Vec::new();
 575                 loop {
 576                         let mut track_read = ReadTrackingReader::new(&mut reader);
 577                         match MaybeReadable::read(&mut track_read) {
 578                                 Ok(Some(v)) => { values.push(v); },
 579                                 Ok(None) => { },
 580                                 // If we failed to read any bytes at all, we reached the end of our TLV
 581                                 // stream and have simply exhausted all entries.
 582                                 Err(ref e) if e == &DecodeError::ShortRead && !track_read.have_read => break,
 583                                 Err(e) => return Err(e),
 584                         }
 585                 }
 586                 Ok(Self(values))
 587         }
 588 }
 589 impl<'a, T> From<&'a Vec<T>> for WithoutLength<&'a Vec<T>> {
 590         fn from(v: &'a Vec<T>) -> Self { Self(v) }
 591 }
 592
 593 macro_rules! impl_for_map {
 594         ($ty: ident, $keybound: ident, $constr: expr) => {
 595                 impl<K, V> Writeable for $ty<K, V>
 596                         where K: Writeable + Eq + $keybound, V: Writeable
 597                 {
 598                         #[inline]
 599                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 600                                 (self.len() as u16).write(w)?;
 601                                 for (key, value) in self.iter() {
 602                                         key.write(w)?;
 603                                         value.write(w)?;
 604                                 }
 605                                 Ok(())
 606                         }
 607                 }
 608
 609                 impl<K, V> Readable for $ty<K, V>
 610                         where K: Readable + Eq + $keybound, V: MaybeReadable
 611                 {
 612                         #[inline]
 613                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 614                                 let len: u16 = Readable::read(r)?;
 615                                 let mut ret = $constr(len as usize);
 616                                 for _ in 0..len {
 617                                         let k = K::read(r)?;
 618                                         let v_opt = V::read(r)?;
 619                                         if let Some(v) = v_opt {
 620                                                 if ret.insert(k, v).is_some() {
 621                                                         return Err(DecodeError::InvalidValue);
 622                                                 }
 623                                         }
 624                                 }
 625                                 Ok(ret)
 626                         }
 627                 }
 628         }
 629 }
 630
 631 impl_for_map!(BTreeMap, Ord, |_| BTreeMap::new());
 632 impl_for_map!(HashMap, Hash, |len| HashMap::with_capacity(len));
 633
 634 // HashSet
 635 impl<T> Writeable for HashSet<T>
 636 where T: Writeable + Eq + Hash
 637 {
 638         #[inline]
 639         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 640                 (self.len() as u16).write(w)?;
 641                 for item in self.iter() {
 642                         item.write(w)?;
 643                 }
 644                 Ok(())
 645         }
 646 }
 647
 648 impl<T> Readable for HashSet<T>
 649 where T: Readable + Eq + Hash
 650 {
 651         #[inline]
 652         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 653                 let len: u16 = Readable::read(r)?;
 654                 let mut ret = HashSet::with_capacity(len as usize);
 655                 for _ in 0..len {
 656                         if !ret.insert(T::read(r)?) {
 657                                 return Err(DecodeError::InvalidValue)
 658                         }
 659                 }
 660                 Ok(ret)
 661         }
 662 }
 663
 664 // Vectors
 665 impl Writeable for Vec<u8> {
 666         #[inline]
 667         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 668                 (self.len() as u16).write(w)?;
 669                 w.write_all(&self)
 670         }
 671 }
 672
 673 impl Readable for Vec<u8> {
 674         #[inline]
 675         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 676                 let len: u16 = Readable::read(r)?;
 677                 let mut ret = Vec::with_capacity(len as usize);
 678                 ret.resize(len as usize, 0);
 679                 r.read_exact(&mut ret)?;
 680                 Ok(ret)
 681         }
 682 }
 683 impl Writeable for Vec<ecdsa::Signature> {
 684         #[inline]
 685         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 686                 (self.len() as u16).write(w)?;
 687                 for e in self.iter() {
 688                         e.write(w)?;
 689                 }
 690                 Ok(())
 691         }
 692 }
 693
 694 impl Readable for Vec<ecdsa::Signature> {
 695         #[inline]
 696         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 697                 let len: u16 = Readable::read(r)?;
 698                 let byte_size = (len as usize)
 699                                 .checked_mul(COMPACT_SIGNATURE_SIZE)
 700                                 .ok_or(DecodeError::BadLengthDescriptor)?;
 701                 if byte_size > MAX_BUF_SIZE {
 702                         return Err(DecodeError::BadLengthDescriptor);
 703                 }
 704                 let mut ret = Vec::with_capacity(len as usize);
 705                 for _ in 0..len { ret.push(Readable::read(r)?); }
 706                 Ok(ret)
 707         }
 708 }
 709
 710 impl Writeable for Script {
 711         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 712                 (self.len() as u16).write(w)?;
 713                 w.write_all(self.as_bytes())
 714         }
 715 }
 716
 717 impl Readable for Script {
 718         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 719                 let len = <u16 as Readable>::read(r)? as usize;
 720                 let mut buf = vec![0; len];
 721                 r.read_exact(&mut buf)?;
 722                 Ok(Script::from(buf))
 723         }
 724 }
 725
 726 impl Writeable for PublicKey {
 727         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 728                 self.serialize().write(w)
 729         }
 730         #[inline]
 731         fn serialized_length(&self) -> usize {
 732                 PUBLIC_KEY_SIZE
 733         }
 734 }
 735
 736 impl Readable for PublicKey {
 737         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 738                 let buf: [u8; PUBLIC_KEY_SIZE] = Readable::read(r)?;
 739                 match PublicKey::from_slice(&buf) {
 740                         Ok(key) => Ok(key),
 741                         Err(_) => return Err(DecodeError::InvalidValue),
 742                 }
 743         }
 744 }
 745
 746 impl Writeable for SecretKey {
 747         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 748                 let mut ser = [0; SECRET_KEY_SIZE];
 749                 ser.copy_from_slice(&self[..]);
 750                 ser.write(w)
 751         }
 752         #[inline]
 753         fn serialized_length(&self) -> usize {
 754                 SECRET_KEY_SIZE
 755         }
 756 }
 757
 758 impl Readable for SecretKey {
 759         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 760                 let buf: [u8; SECRET_KEY_SIZE] = Readable::read(r)?;
 761                 match SecretKey::from_slice(&buf) {
 762                         Ok(key) => Ok(key),
 763                         Err(_) => return Err(DecodeError::InvalidValue),
 764                 }
 765         }
 766 }
 767
 768 impl Writeable for Sha256dHash {
 769         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 770                 w.write_all(&self[..])
 771         }
 772 }
 773
 774 impl Readable for Sha256dHash {
 775         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 776                 use bitcoin::hashes::Hash;
 777
 778                 let buf: [u8; 32] = Readable::read(r)?;
 779                 Ok(Sha256dHash::from_slice(&buf[..]).unwrap())
 780         }
 781 }
 782
 783 impl Writeable for ecdsa::Signature {
 784         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 785                 self.serialize_compact().write(w)
 786         }
 787 }
 788
 789 impl Readable for ecdsa::Signature {
 790         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 791                 let buf: [u8; COMPACT_SIGNATURE_SIZE] = Readable::read(r)?;
 792                 match ecdsa::Signature::from_compact(&buf) {
 793                         Ok(sig) => Ok(sig),
 794                         Err(_) => return Err(DecodeError::InvalidValue),
 795                 }
 796         }
 797 }
 798
 799 impl Writeable for schnorr::Signature {
 800         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 801                 self.as_ref().write(w)
 802         }
 803 }
 804
 805 impl Readable for schnorr::Signature {
 806         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 807                 let buf: [u8; SCHNORR_SIGNATURE_SIZE] = Readable::read(r)?;
 808                 match schnorr::Signature::from_slice(&buf) {
 809                         Ok(sig) => Ok(sig),
 810                         Err(_) => return Err(DecodeError::InvalidValue),
 811                 }
 812         }
 813 }
 814
 815 impl Writeable for PaymentPreimage {
 816         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 817                 self.0.write(w)
 818         }
 819 }
 820
 821 impl Readable for PaymentPreimage {
 822         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 823                 let buf: [u8; 32] = Readable::read(r)?;
 824                 Ok(PaymentPreimage(buf))
 825         }
 826 }
 827
 828 impl Writeable for PaymentHash {
 829         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 830                 self.0.write(w)
 831         }
 832 }
 833
 834 impl Readable for PaymentHash {
 835         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 836                 let buf: [u8; 32] = Readable::read(r)?;
 837                 Ok(PaymentHash(buf))
 838         }
 839 }
 840
 841 impl Writeable for PaymentSecret {
 842         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 843                 self.0.write(w)
 844         }
 845 }
 846
 847 impl Readable for PaymentSecret {
 848         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 849                 let buf: [u8; 32] = Readable::read(r)?;
 850                 Ok(PaymentSecret(buf))
 851         }
 852 }
 853
 854 impl<T: Writeable> Writeable for Box<T> {
 855         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 856                 T::write(&**self, w)
 857         }
 858 }
 859
 860 impl<T: Readable> Readable for Box<T> {
 861         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 862                 Ok(Box::new(Readable::read(r)?))
 863         }
 864 }
 865
 866 impl<T: Writeable> Writeable for Option<T> {
 867         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 868                 match *self {
 869                         None => 0u8.write(w)?,
 870                         Some(ref data) => {
 871                                 BigSize(data.serialized_length() as u64 + 1).write(w)?;
 872                                 data.write(w)?;
 873                         }
 874                 }
 875                 Ok(())
 876         }
 877 }
 878
 879 impl<T: Readable> Readable for Option<T>
 880 {
 881         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 882                 let len: BigSize = Readable::read(r)?;
 883                 match len.0 {
 884                         0 => Ok(None),
 885                         len => {
 886                                 let mut reader = FixedLengthReader::new(r, len - 1);
 887                                 Ok(Some(Readable::read(&mut reader)?))
 888                         }
 889                 }
 890         }
 891 }
 892
 893 impl Writeable for Txid {
 894         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 895                 w.write_all(&self[..])
 896         }
 897 }
 898
 899 impl Readable for Txid {
 900         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 901                 use bitcoin::hashes::Hash;
 902
 903                 let buf: [u8; 32] = Readable::read(r)?;
 904                 Ok(Txid::from_slice(&buf[..]).unwrap())
 905         }
 906 }
 907
 908 impl Writeable for BlockHash {
 909         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 910                 w.write_all(&self[..])
 911         }
 912 }
 913
 914 impl Readable for BlockHash {
 915         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 916                 use bitcoin::hashes::Hash;
 917
 918                 let buf: [u8; 32] = Readable::read(r)?;
 919                 Ok(BlockHash::from_slice(&buf[..]).unwrap())
 920         }
 921 }
 922
 923 impl Writeable for ChainHash {
 924         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 925                 w.write_all(self.as_bytes())
 926         }
 927 }
 928
 929 impl Readable for ChainHash {
 930         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 931                 let buf: [u8; 32] = Readable::read(r)?;
 932                 Ok(ChainHash::from(&buf[..]))
 933         }
 934 }
 935
 936 impl Writeable for OutPoint {
 937         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 938                 self.txid.write(w)?;
 939                 self.vout.write(w)?;
 940                 Ok(())
 941         }
 942 }
 943
 944 impl Readable for OutPoint {
 945         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 946                 let txid = Readable::read(r)?;
 947                 let vout = Readable::read(r)?;
 948                 Ok(OutPoint {
 949                         txid,
 950                         vout,
 951                 })
 952         }
 953 }
 954
 955 macro_rules! impl_consensus_ser {
 956         ($bitcoin_type: ty) => {
 957                 impl Writeable for $bitcoin_type {
 958                         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 959                                 match self.consensus_encode(&mut WriterWriteAdaptor(writer)) {
 960                                         Ok(_) => Ok(()),
 961                                         Err(e) => Err(e),
 962                                 }
 963                         }
 964                 }
 965
 966                 impl Readable for $bitcoin_type {
 967                         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 968                                 match consensus::encode::Decodable::consensus_decode(r) {
 969                                         Ok(t) => Ok(t),
 970                                         Err(consensus::encode::Error::Io(ref e)) if e.kind() == io::ErrorKind::UnexpectedEof => Err(DecodeError::ShortRead),
 971                                         Err(consensus::encode::Error::Io(e)) => Err(DecodeError::Io(e.kind())),
 972                                         Err(_) => Err(DecodeError::InvalidValue),
 973                                 }
 974                         }
 975                 }
 976         }
 977 }
 978 impl_consensus_ser!(Transaction);
 979 impl_consensus_ser!(TxOut);
 980
 981 impl<T: Readable> Readable for Mutex<T> {
 982         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 983                 let t: T = Readable::read(r)?;
 984                 Ok(Mutex::new(t))
 985         }
 986 }
 987 impl<T: Writeable> Writeable for Mutex<T> {
 988         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 989                 self.lock().unwrap().write(w)
 990         }
 991 }
 992
 993 impl<A: Readable, B: Readable> Readable for (A, B) {
 994         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 995                 let a: A = Readable::read(r)?;
 996                 let b: B = Readable::read(r)?;
 997                 Ok((a, b))
 998         }
 999 }
1000 impl<A: Writeable, B: Writeable> Writeable for (A, B) {
1001         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1002                 self.0.write(w)?;
1003                 self.1.write(w)
1004         }
1005 }
1006
1007 impl<A: Readable, B: Readable, C: Readable> Readable for (A, B, C) {
1008         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1009                 let a: A = Readable::read(r)?;
1010                 let b: B = Readable::read(r)?;
1011                 let c: C = Readable::read(r)?;
1012                 Ok((a, b, c))
1013         }
1014 }
1015 impl<A: Writeable, B: Writeable, C: Writeable> Writeable for (A, B, C) {
1016         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1017                 self.0.write(w)?;
1018                 self.1.write(w)?;
1019                 self.2.write(w)
1020         }
1021 }
1022
1023 impl Writeable for () {
1024         fn write<W: Writer>(&self, _: &mut W) -> Result<(), io::Error> {
1025                 Ok(())
1026         }
1027 }
1028 impl Readable for () {
1029         fn read<R: Read>(_r: &mut R) -> Result<Self, DecodeError> {
1030                 Ok(())
1031         }
1032 }
1033
1034 impl Writeable for String {
1035         #[inline]
1036         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1037                 (self.len() as u16).write(w)?;
1038                 w.write_all(self.as_bytes())
1039         }
1040 }
1041 impl Readable for String {
1042         #[inline]
1043         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1044                 let v: Vec<u8> = Readable::read(r)?;
1045                 let ret = String::from_utf8(v).map_err(|_| DecodeError::InvalidValue)?;
1046                 Ok(ret)
1047         }
1048 }
1049
1050 /// Represents a hostname for serialization purposes.
1051 /// Only the character set and length will be validated.
1052 /// The character set consists of ASCII alphanumeric characters, hyphens, and periods.
1053 /// Its length is guaranteed to be representable by a single byte.
1054 /// This serialization is used by [`BOLT 7`] hostnames.
1055 ///
1056 /// [`BOLT 7`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md
1057 #[derive(Clone, Debug, PartialEq, Eq)]
1058 pub struct Hostname(String);
1059 impl Hostname {
1060         /// Returns the length of the hostname.
1061         pub fn len(&self) -> u8 {
1062                 (&self.0).len() as u8
1063         }
1064 }
1065 impl Deref for Hostname {
1066         type Target = String;
1067
1068         fn deref(&self) -> &Self::Target {
1069                 &self.0
1070         }
1071 }
1072 impl From<Hostname> for String {
1073         fn from(hostname: Hostname) -> Self {
1074                 hostname.0
1075         }
1076 }
1077 impl TryFrom<Vec<u8>> for Hostname {
1078         type Error = ();
1079
1080         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1081                 if let Ok(s) = String::from_utf8(bytes) {
1082                         Hostname::try_from(s)
1083                 } else {
1084                         Err(())
1085                 }
1086         }
1087 }
1088 impl TryFrom<String> for Hostname {
1089         type Error = ();
1090
1091         fn try_from(s: String) -> Result<Self, Self::Error> {
1092                 if s.len() <= 255 && s.chars().all(|c|
1093                         c.is_ascii_alphanumeric() ||
1094                         c == '.' ||
1095                         c == '-'
1096                 ) {
1097                         Ok(Hostname(s))
1098                 } else {
1099                         Err(())
1100                 }
1101         }
1102 }
1103 impl Writeable for Hostname {
1104         #[inline]
1105         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1106                 self.len().write(w)?;
1107                 w.write_all(self.as_bytes())
1108         }
1109 }
1110 impl Readable for Hostname {
1111         #[inline]
1112         fn read<R: Read>(r: &mut R) -> Result<Hostname, DecodeError> {
1113                 let len: u8 = Readable::read(r)?;
1114                 let mut vec = Vec::with_capacity(len.into());
1115                 vec.resize(len.into(), 0);
1116                 r.read_exact(&mut vec)?;
1117                 Hostname::try_from(vec).map_err(|_| DecodeError::InvalidValue)
1118         }
1119 }
1120
1121 impl Writeable for Duration {
1122         #[inline]
1123         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1124                 self.as_secs().write(w)?;
1125                 self.subsec_nanos().write(w)
1126         }
1127 }
1128 impl Readable for Duration {
1129         #[inline]
1130         fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
1131                 let secs = Readable::read(r)?;
1132                 let nanos = Readable::read(r)?;
1133                 Ok(Duration::new(secs, nanos))
1134         }
1135 }
1136
1137 #[cfg(test)]
1138 mod tests {
1139         use core::convert::TryFrom;
1140         use crate::util::ser::{Readable, Hostname, Writeable};
1141
1142         #[test]
1143         fn hostname_conversion() {
1144                 assert_eq!(Hostname::try_from(String::from("a-test.com")).unwrap().as_str(), "a-test.com");
1145
1146                 assert!(Hostname::try_from(String::from("\"")).is_err());
1147                 assert!(Hostname::try_from(String::from("$")).is_err());
1148                 assert!(Hostname::try_from(String::from("⚡")).is_err());
1149                 let mut large_vec = Vec::with_capacity(256);
1150                 large_vec.resize(256, b'A');
1151                 assert!(Hostname::try_from(String::from_utf8(large_vec).unwrap()).is_err());
1152         }
1153
1154         #[test]
1155         fn hostname_serialization() {
1156                 let hostname = Hostname::try_from(String::from("test")).unwrap();
1157                 let mut buf: Vec<u8> = Vec::new();
1158                 hostname.write(&mut buf).unwrap();
1159                 assert_eq!(Hostname::read(&mut buf.as_slice()).unwrap().as_str(), "test");
1160         }
1161 }