git.bitcoin.ninja Git - rust-lightning/blob - lightning/src/util/ser_macros.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 //! Some macros that implement [`Readable`]/[`Writeable`] traits for lightning messages.
  11 //! They also handle serialization and deserialization of TLVs.
  12 //!
  13 //! [`Readable`]: crate::util::ser::Readable
  14 //! [`Writeable`]: crate::util::ser::Writeable
  15
  16 /// Implements serialization for a single TLV record.
  17 /// This is exported for use by other exported macros, do not use directly.
  18 #[doc(hidden)]
  19 #[macro_export]
  20 macro_rules! _encode_tlv {
  21         ($stream: expr, $type: expr, $field: expr, (default_value, $default: expr)) => {
  22                 $crate::_encode_tlv!($stream, $type, $field, required)
  23         };
  24         ($stream: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
  25                 let _ = &$field; // Ensure we "use" the $field
  26         };
  27         ($stream: expr, $type: expr, $field: expr, required) => {
  28                 BigSize($type).write($stream)?;
  29                 BigSize($field.serialized_length() as u64).write($stream)?;
  30                 $field.write($stream)?;
  31         };
  32         ($stream: expr, $type: expr, $field: expr, vec_type) => {
  33                 $crate::_encode_tlv!($stream, $type, $crate::util::ser::WithoutLength(&$field), required);
  34         };
  35         ($stream: expr, $optional_type: expr, $optional_field: expr, option) => {
  36                 if let Some(ref field) = $optional_field {
  37                         BigSize($optional_type).write($stream)?;
  38                         BigSize(field.serialized_length() as u64).write($stream)?;
  39                         field.write($stream)?;
  40                 }
  41         };
  42         ($stream: expr, $type: expr, $field: expr, (option, encoding: ($fieldty: ty, $encoding: ident))) => {
  43                 $crate::_encode_tlv!($stream, $type, $field.map(|f| $encoding(f)), option);
  44         };
  45         ($stream: expr, $type: expr, $field: expr, (option, encoding: $fieldty: ty)) => {
  46                 $crate::_encode_tlv!($stream, $type, $field, option);
  47         };
  48 }
  49
  50 /// Panics if the last seen TLV type is not numerically less than the TLV type currently being checked.
  51 /// This is exported for use by other exported macros, do not use directly.
  52 #[doc(hidden)]
  53 #[macro_export]
  54 macro_rules! _check_encoded_tlv_order {
  55         ($last_type: expr, $type: expr, (static_value, $value: expr)) => { };
  56         ($last_type: expr, $type: expr, $fieldty: tt) => {
  57                 if let Some(t) = $last_type {
  58                         #[allow(unused_comparisons)] // Note that $type may be 0 making the following comparison always false
  59                         (debug_assert!(t < $type))
  60                 }
  61                 $last_type = Some($type);
  62         };
  63 }
  64
  65 /// Implements the TLVs serialization part in a [`Writeable`] implementation of a struct.
  66 ///
  67 /// This should be called inside a method which returns `Result<_, `[`io::Error`]`>`, such as
  68 /// [`Writeable::write`]. It will only return an `Err` if the stream `Err`s or [`Writeable::write`]
  69 /// on one of the fields `Err`s.
  70 ///
  71 /// `$stream` must be a `&mut `[`Writer`] which will receive the bytes for each TLV in the stream.
  72 ///
  73 /// Fields MUST be sorted in `$type`-order.
  74 ///
  75 /// Note that the lightning TLV requirements require that a single type not appear more than once,
  76 /// that TLVs are sorted in type-ascending order, and that any even types be understood by the
  77 /// decoder.
  78 ///
  79 /// Any `option` fields which have a value of `None` will not be serialized at all.
  80 ///
  81 /// For example,
  82 /// ```
  83 /// # use lightning::encode_tlv_stream;
  84 /// # fn write<W: lightning::util::ser::Writer> (stream: &mut W) -> Result<(), lightning::io::Error> {
  85 /// let mut required_value = 0u64;
  86 /// let mut optional_value: Option<u64> = None;
  87 /// encode_tlv_stream!(stream, {
  88 ///     (0, required_value, required),
  89 ///     (1, Some(42u64), option),
  90 ///     (2, optional_value, option),
  91 /// });
  92 /// // At this point `required_value` has been written as a TLV of type 0, `42u64` has been written
  93 /// // as a TLV of type 1 (indicating the reader may ignore it if it is not understood), and *no*
  94 /// // TLV is written with type 2.
  95 /// # Ok(())
  96 /// # }
  97 /// ```
  98 ///
  99 /// [`Writeable`]: crate::util::ser::Writeable
 100 /// [`io::Error`]: crate::io::Error
 101 /// [`Writeable::write`]: crate::util::ser::Writeable::write
 102 /// [`Writer`]: crate::util::ser::Writer
 103 #[macro_export]
 104 macro_rules! encode_tlv_stream {
 105         ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => { {
 106                 #[allow(unused_imports)]
 107                 use $crate::{
 108                         ln::msgs::DecodeError,
 109                         util::ser,
 110                         util::ser::BigSize,
 111                         util::ser::Writeable,
 112                 };
 113
 114                 $(
 115                         $crate::_encode_tlv!($stream, $type, $field, $fieldty);
 116                 )*
 117
 118                 #[allow(unused_mut, unused_variables, unused_assignments)]
 119                 #[cfg(debug_assertions)]
 120                 {
 121                         let mut last_seen: Option<u64> = None;
 122                         $(
 123                                 $crate::_check_encoded_tlv_order!(last_seen, $type, $fieldty);
 124                         )*
 125                 }
 126         } }
 127 }
 128
 129 /// Adds the length of the serialized field to a [`LengthCalculatingWriter`].
 130 /// This is exported for use by other exported macros, do not use directly.
 131 ///
 132 /// [`LengthCalculatingWriter`]: crate::util::ser::LengthCalculatingWriter
 133 #[doc(hidden)]
 134 #[macro_export]
 135 macro_rules! _get_varint_length_prefixed_tlv_length {
 136         ($len: expr, $type: expr, $field: expr, (default_value, $default: expr)) => {
 137                 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
 138         };
 139         ($len: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
 140         };
 141         ($len: expr, $type: expr, $field: expr, required) => {
 142                 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
 143                 let field_len = $field.serialized_length();
 144                 BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
 145                 $len.0 += field_len;
 146         };
 147         ($len: expr, $type: expr, $field: expr, vec_type) => {
 148                 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $crate::util::ser::WithoutLength(&$field), required);
 149         };
 150         ($len: expr, $optional_type: expr, $optional_field: expr, option) => {
 151                 if let Some(ref field) = $optional_field {
 152                         BigSize($optional_type).write(&mut $len).expect("No in-memory data may fail to serialize");
 153                         let field_len = field.serialized_length();
 154                         BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
 155                         $len.0 += field_len;
 156                 }
 157         };
 158 }
 159
 160 /// See the documentation of [`write_tlv_fields`].
 161 /// This is exported for use by other exported macros, do not use directly.
 162 #[doc(hidden)]
 163 #[macro_export]
 164 macro_rules! _encode_varint_length_prefixed_tlv {
 165         ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),*}) => { {
 166                 use $crate::util::ser::BigSize;
 167                 let len = {
 168                         #[allow(unused_mut)]
 169                         let mut len = $crate::util::ser::LengthCalculatingWriter(0);
 170                         $(
 171                                 $crate::_get_varint_length_prefixed_tlv_length!(len, $type, $field, $fieldty);
 172                         )*
 173                         len.0
 174                 };
 175                 BigSize(len as u64).write($stream)?;
 176                 $crate::encode_tlv_stream!($stream, { $(($type, $field, $fieldty)),* });
 177         } }
 178 }
 179
 180 /// Errors if there are missing required TLV types between the last seen type and the type currently being processed.
 181 /// This is exported for use by other exported macros, do not use directly.
 182 #[doc(hidden)]
 183 #[macro_export]
 184 macro_rules! _check_decoded_tlv_order {
 185         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value, $default: expr)) => {{
 186                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
 187                 let invalid_order = ($last_seen_type.is_none() || $last_seen_type.unwrap() < $type) && $typ.0 > $type;
 188                 if invalid_order {
 189                         $field = $default.into();
 190                 }
 191         }};
 192         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {
 193         };
 194         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
 195                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
 196                 let invalid_order = ($last_seen_type.is_none() || $last_seen_type.unwrap() < $type) && $typ.0 > $type;
 197                 if invalid_order {
 198                         return Err(DecodeError::InvalidValue);
 199                 }
 200         }};
 201         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, option) => {{
 202                 // no-op
 203         }};
 204         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, vec_type) => {{
 205                 // no-op
 206         }};
 207         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, ignorable) => {{
 208                 // no-op
 209         }};
 210         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
 211                 // no-op
 212         }};
 213         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (option, encoding: $encoding: tt)) => {{
 214                 // no-op
 215         }};
 216 }
 217
 218 /// Errors if there are missing required TLV types after the last seen type.
 219 /// This is exported for use by other exported macros, do not use directly.
 220 #[doc(hidden)]
 221 #[macro_export]
 222 macro_rules! _check_missing_tlv {
 223         ($last_seen_type: expr, $type: expr, $field: ident, (default_value, $default: expr)) => {{
 224                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
 225                 let missing_req_type = $last_seen_type.is_none() || $last_seen_type.unwrap() < $type;
 226                 if missing_req_type {
 227                         $field = $default.into();
 228                 }
 229         }};
 230         ($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
 231                 $field = $value;
 232         };
 233         ($last_seen_type: expr, $type: expr, $field: ident, required) => {{
 234                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
 235                 let missing_req_type = $last_seen_type.is_none() || $last_seen_type.unwrap() < $type;
 236                 if missing_req_type {
 237                         return Err(DecodeError::InvalidValue);
 238                 }
 239         }};
 240         ($last_seen_type: expr, $type: expr, $field: ident, vec_type) => {{
 241                 // no-op
 242         }};
 243         ($last_seen_type: expr, $type: expr, $field: ident, option) => {{
 244                 // no-op
 245         }};
 246         ($last_seen_type: expr, $type: expr, $field: ident, ignorable) => {{
 247                 // no-op
 248         }};
 249         ($last_seen_type: expr, $type: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
 250                 // no-op
 251         }};
 252         ($last_seen_type: expr, $type: expr, $field: ident, (option, encoding: $encoding: tt)) => {{
 253                 // no-op
 254         }};
 255 }
 256
 257 /// Implements deserialization for a single TLV record.
 258 /// This is exported for use by other exported macros, do not use directly.
 259 #[doc(hidden)]
 260 #[macro_export]
 261 macro_rules! _decode_tlv {
 262         ($reader: expr, $field: ident, (default_value, $default: expr)) => {{
 263                 $crate::_decode_tlv!($reader, $field, required)
 264         }};
 265         ($reader: expr, $field: ident, (static_value, $value: expr)) => {{
 266         }};
 267         ($reader: expr, $field: ident, required) => {{
 268                 $field = $crate::util::ser::Readable::read(&mut $reader)?;
 269         }};
 270         ($reader: expr, $field: ident, vec_type) => {{
 271                 let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::Readable::read(&mut $reader)?;
 272                 $field = Some(f.0);
 273         }};
 274         ($reader: expr, $field: ident, option) => {{
 275                 $field = Some($crate::util::ser::Readable::read(&mut $reader)?);
 276         }};
 277         ($reader: expr, $field: ident, ignorable) => {{
 278                 $field = $crate::util::ser::MaybeReadable::read(&mut $reader)?;
 279         }};
 280         ($reader: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
 281                 $field = Some($trait::read(&mut $reader $(, $read_arg)*)?);
 282         }};
 283         ($reader: expr, $field: ident, (option, encoding: ($fieldty: ty, $encoding: ident))) => {{
 284                 $field = {
 285                         let field: $encoding<$fieldty> = ser::Readable::read(&mut $reader)?;
 286                         Some(field.0)
 287                 };
 288         }};
 289         ($reader: expr, $field: ident, (option, encoding: $fieldty: ty)) => {{
 290                 $crate::_decode_tlv!($reader, $field, option);
 291         }};
 292 }
 293
 294 /// Checks if `$val` matches `$type`.
 295 /// This is exported for use by other exported macros, do not use directly.
 296 #[doc(hidden)]
 297 #[macro_export]
 298 macro_rules! _decode_tlv_stream_match_check {
 299         ($val: ident, $type: expr, (static_value, $value: expr)) => { false };
 300         ($val: ident, $type: expr, $fieldty: tt) => { $val == $type }
 301 }
 302
 303 /// Implements the TLVs deserialization part in a [`Readable`] implementation of a struct.
 304 ///
 305 /// This should be called inside a method which returns `Result<_, `[`DecodeError`]`>`, such as
 306 /// [`Readable::read`]. It will either return an `Err` or ensure all `required` fields have been
 307 /// read and optionally read `optional` fields.
 308 ///
 309 /// `$stream` must be a [`Read`] and will be fully consumed, reading until no more bytes remain
 310 /// (i.e. it returns [`DecodeError::ShortRead`]).
 311 ///
 312 /// Fields MUST be sorted in `$type`-order.
 313 ///
 314 /// Note that the lightning TLV requirements require that a single type not appear more than once,
 315 /// that TLVs are sorted in type-ascending order, and that any even types be understood by the
 316 /// decoder.
 317 ///
 318 /// For example,
 319 /// ```
 320 /// # use lightning::decode_tlv_stream;
 321 /// # fn read<R: lightning::io::Read> (stream: R) -> Result<(), lightning::ln::msgs::DecodeError> {
 322 /// let mut required_value = 0u64;
 323 /// let mut optional_value: Option<u64> = None;
 324 /// decode_tlv_stream!(stream, {
 325 ///     (0, required_value, required),
 326 ///     (2, optional_value, option),
 327 /// });
 328 /// // At this point, `required_value` has been overwritten with the TLV with type 0.
 329 /// // `optional_value` may have been overwritten, setting it to `Some` if a TLV with type 2 was
 330 /// // present.
 331 /// # Ok(())
 332 /// # }
 333 /// ```
 334 ///
 335 /// [`Readable`]: crate::util::ser::Readable
 336 /// [`DecodeError`]: crate::ln::msgs::DecodeError
 337 /// [`Readable::read`]: crate::util::ser::Readable::read
 338 /// [`Read`]: crate::io::Read
 339 /// [`DecodeError::ShortRead`]: crate::ln::msgs::DecodeError::ShortRead
 340 #[macro_export]
 341 macro_rules! decode_tlv_stream {
 342         ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
 343                 let rewind = |_, _| { unreachable!() };
 344                 $crate::_decode_tlv_stream_range!($stream, .., rewind, {$(($type, $field, $fieldty)),*});
 345         }
 346 }
 347
 348 /// Similar to [`decode_tlv_stream`] with a custom TLV decoding capabilities.
 349 ///
 350 /// `$decode_custom_tlv` is a closure that may be optionally provided to handle custom message types.
 351 /// If it is provided, it will be called with the custom type and the [`FixedLengthReader`] containing
 352 /// the message contents. It should return `Ok(true)` if the custom message is successfully parsed,
 353 /// `Ok(false)` if the message type is unknown, and `Err(`[`DecodeError`]`)` if parsing fails.
 354 ///
 355 /// [`FixedLengthReader`]: crate::util::ser::FixedLengthReader
 356 /// [`DecodeError`]: crate::ln::msgs::DecodeError
 357 macro_rules! decode_tlv_stream_with_custom_tlv_decode {
 358         ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 359          $(, $decode_custom_tlv: expr)?) => { {
 360                 let rewind = |_, _| { unreachable!() };
 361                 _decode_tlv_stream_range!(
 362                         $stream, .., rewind, {$(($type, $field, $fieldty)),*} $(, $decode_custom_tlv)?
 363                 );
 364         } }
 365 }
 366
 367 #[doc(hidden)]
 368 #[macro_export]
 369 macro_rules! _decode_tlv_stream_range {
 370         ($stream: expr, $range: expr, $rewind: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 371          $(, $decode_custom_tlv: expr)?) => { {
 372                 use core::ops::RangeBounds;
 373                 use $crate::ln::msgs::DecodeError;
 374                 let mut last_seen_type: Option<u64> = None;
 375                 let mut stream_ref = $stream;
 376                 'tlv_read: loop {
 377                         use $crate::util::ser;
 378
 379                         // First decode the type of this TLV:
 380                         let typ: ser::BigSize = {
 381                                 // We track whether any bytes were read during the consensus_decode call to
 382                                 // determine whether we should break or return ShortRead if we get an
 383                                 // UnexpectedEof. This should in every case be largely cosmetic, but its nice to
 384                                 // pass the TLV test vectors exactly, which require this distinction.
 385                                 let mut tracking_reader = ser::ReadTrackingReader::new(&mut stream_ref);
 386                                 match <$crate::util::ser::BigSize as $crate::util::ser::Readable>::read(&mut tracking_reader) {
 387                                         Err(DecodeError::ShortRead) => {
 388                                                 if !tracking_reader.have_read {
 389                                                         break 'tlv_read;
 390                                                 } else {
 391                                                         return Err(DecodeError::ShortRead);
 392                                                 }
 393                                         },
 394                                         Err(e) => return Err(e),
 395                                         Ok(t) => if $range.contains(&t.0) { t } else {
 396                                                 drop(tracking_reader);
 397
 398                                                 // Assumes the type id is minimally encoded, which is enforced on read.
 399                                                 use $crate::util::ser::Writeable;
 400                                                 let bytes_read = t.serialized_length();
 401                                                 $rewind(stream_ref, bytes_read);
 402                                                 break 'tlv_read;
 403                                         },
 404                                 }
 405                         };
 406
 407                         // Types must be unique and monotonically increasing:
 408                         match last_seen_type {
 409                                 Some(t) if typ.0 <= t => {
 410                                         return Err(DecodeError::InvalidValue);
 411                                 },
 412                                 _ => {},
 413                         }
 414                         // As we read types, make sure we hit every required type between `last_seen_type` and `typ`:
 415                         $({
 416                                 $crate::_check_decoded_tlv_order!(last_seen_type, typ, $type, $field, $fieldty);
 417                         })*
 418                         last_seen_type = Some(typ.0);
 419
 420                         // Finally, read the length and value itself:
 421                         let length: ser::BigSize = $crate::util::ser::Readable::read(&mut stream_ref)?;
 422                         let mut s = ser::FixedLengthReader::new(&mut stream_ref, length.0);
 423                         match typ.0 {
 424                                 $(_t if $crate::_decode_tlv_stream_match_check!(_t, $type, $fieldty) => {
 425                                         $crate::_decode_tlv!(s, $field, $fieldty);
 426                                         if s.bytes_remain() {
 427                                                 s.eat_remaining()?; // Return ShortRead if there's actually not enough bytes
 428                                                 return Err(DecodeError::InvalidValue);
 429                                         }
 430                                 },)*
 431                                 t => {
 432                                         $(
 433                                                 if $decode_custom_tlv(t, &mut s)? {
 434                                                         // If a custom TLV was successfully read (i.e. decode_custom_tlv returns true),
 435                                                         // continue to the next TLV read.
 436                                                         s.eat_remaining()?;
 437                                                         continue 'tlv_read;
 438                                                 }
 439                                         )?
 440                                         if t % 2 == 0 {
 441                                                 return Err(DecodeError::UnknownRequiredFeature);
 442                                         }
 443                                 }
 444                         }
 445                         s.eat_remaining()?;
 446                 }
 447                 // Make sure we got to each required type after we've read every TLV:
 448                 $({
 449                         $crate::_check_missing_tlv!(last_seen_type, $type, $field, $fieldty);
 450                 })*
 451         } }
 452 }
 453
 454 macro_rules! impl_writeable_msg {
 455         ($st:ident, {$($field:ident),* $(,)*}, {$(($type: expr, $tlvfield: ident, $fieldty: tt)),* $(,)*}) => {
 456                 impl $crate::util::ser::Writeable for $st {
 457                         fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
 458                                 $( self.$field.write(w)?; )*
 459                                 encode_tlv_stream!(w, {$(($type, self.$tlvfield, $fieldty)),*});
 460                                 Ok(())
 461                         }
 462                 }
 463                 impl $crate::util::ser::Readable for $st {
 464                         fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 465                                 $(let $field = $crate::util::ser::Readable::read(r)?;)*
 466                                 $(_init_tlv_field_var!($tlvfield, $fieldty);)*
 467                                 decode_tlv_stream!(r, {$(($type, $tlvfield, $fieldty)),*});
 468                                 Ok(Self {
 469                                         $($field),*,
 470                                         $($tlvfield),*
 471                                 })
 472                         }
 473                 }
 474         }
 475 }
 476
 477 macro_rules! impl_writeable {
 478         ($st:ident, {$($field:ident),*}) => {
 479                 impl $crate::util::ser::Writeable for $st {
 480                         fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
 481                                 $( self.$field.write(w)?; )*
 482                                 Ok(())
 483                         }
 484
 485                         #[inline]
 486                         fn serialized_length(&self) -> usize {
 487                                 let mut len_calc = 0;
 488                                 $( len_calc += self.$field.serialized_length(); )*
 489                                 return len_calc;
 490                         }
 491                 }
 492
 493                 impl $crate::util::ser::Readable for $st {
 494                         fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 495                                 Ok(Self {
 496                                         $($field: $crate::util::ser::Readable::read(r)?),*
 497                                 })
 498                         }
 499                 }
 500         }
 501 }
 502
 503 /// Write out two bytes to indicate the version of an object.
 504 /// $this_version represents a unique version of a type. Incremented whenever the type's
 505 ///               serialization format has changed or has a new interpretation. Used by a type's
 506 ///               reader to determine how to interpret fields or if it can understand a serialized
 507 ///               object.
 508 /// $min_version_that_can_read_this is the minimum reader version which can understand this
 509 ///                                 serialized object. Previous versions will simply err with a
 510 ///                                 [`DecodeError::UnknownVersion`].
 511 ///
 512 /// Updates to either `$this_version` or `$min_version_that_can_read_this` should be included in
 513 /// release notes.
 514 ///
 515 /// Both version fields can be specific to this type of object.
 516 ///
 517 /// [`DecodeError::UnknownVersion`]: crate::ln::msgs::DecodeError::UnknownVersion
 518 macro_rules! write_ver_prefix {
 519         ($stream: expr, $this_version: expr, $min_version_that_can_read_this: expr) => {
 520                 $stream.write_all(&[$this_version; 1])?;
 521                 $stream.write_all(&[$min_version_that_can_read_this; 1])?;
 522         }
 523 }
 524
 525 /// Writes out a suffix to an object as a length-prefixed TLV stream which contains potentially
 526 /// backwards-compatible, optional fields which old nodes can happily ignore.
 527 ///
 528 /// It is written out in TLV format and, as with all TLV fields, unknown even fields cause a
 529 /// [`DecodeError::UnknownRequiredFeature`] error, with unknown odd fields ignored.
 530 ///
 531 /// This is the preferred method of adding new fields that old nodes can ignore and still function
 532 /// correctly.
 533 ///
 534 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
 535 #[macro_export]
 536 macro_rules! write_tlv_fields {
 537         ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => {
 538                 $crate::_encode_varint_length_prefixed_tlv!($stream, {$(($type, $field, $fieldty)),*})
 539         }
 540 }
 541
 542 /// Reads a prefix added by [`write_ver_prefix`], above. Takes the current version of the
 543 /// serialization logic for this object. This is compared against the
 544 /// `$min_version_that_can_read_this` added by [`write_ver_prefix`].
 545 macro_rules! read_ver_prefix {
 546         ($stream: expr, $this_version: expr) => { {
 547                 let ver: u8 = Readable::read($stream)?;
 548                 let min_ver: u8 = Readable::read($stream)?;
 549                 if min_ver > $this_version {
 550                         return Err(DecodeError::UnknownVersion);
 551                 }
 552                 ver
 553         } }
 554 }
 555
 556 /// Reads a suffix added by [`write_tlv_fields`].
 557 ///
 558 /// [`write_tlv_fields`]: crate::write_tlv_fields
 559 #[macro_export]
 560 macro_rules! read_tlv_fields {
 561         ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => { {
 562                 let tlv_len: $crate::util::ser::BigSize = $crate::util::ser::Readable::read($stream)?;
 563                 let mut rd = $crate::util::ser::FixedLengthReader::new($stream, tlv_len.0);
 564                 $crate::decode_tlv_stream!(&mut rd, {$(($type, $field, $fieldty)),*});
 565                 rd.eat_remaining().map_err(|_| $crate::ln::msgs::DecodeError::ShortRead)?;
 566         } }
 567 }
 568
 569 /// Initializes the struct fields.
 570 /// This is exported for use by other exported macros, do not use directly.
 571 #[doc(hidden)]
 572 #[macro_export]
 573 macro_rules! _init_tlv_based_struct_field {
 574         ($field: ident, (default_value, $default: expr)) => {
 575                 $field.0.unwrap()
 576         };
 577         ($field: ident, (static_value, $value: expr)) => {
 578                 $field
 579         };
 580         ($field: ident, option) => {
 581                 $field
 582         };
 583         ($field: ident, required) => {
 584                 $field.0.unwrap()
 585         };
 586         ($field: ident, vec_type) => {
 587                 $field.unwrap()
 588         };
 589 }
 590
 591 /// Initializes the variable we are going to read the TLV into.
 592 /// This is exported for use by other exported macros, do not use directly.
 593 #[doc(hidden)]
 594 #[macro_export]
 595 macro_rules! _init_tlv_field_var {
 596         ($field: ident, (default_value, $default: expr)) => {
 597                 let mut $field = $crate::util::ser::OptionDeserWrapper(None);
 598         };
 599         ($field: ident, (static_value, $value: expr)) => {
 600                 let $field;
 601         };
 602         ($field: ident, required) => {
 603                 let mut $field = $crate::util::ser::OptionDeserWrapper(None);
 604         };
 605         ($field: ident, vec_type) => {
 606                 let mut $field = Some(Vec::new());
 607         };
 608         ($field: ident, option) => {
 609                 let mut $field = None;
 610         };
 611 }
 612
 613 /// Equivalent to running [`_init_tlv_field_var`] then [`read_tlv_fields`].
 614 /// This is exported for use by other exported macros, do not use directly.
 615 #[doc(hidden)]
 616 #[macro_export]
 617 macro_rules! _init_and_read_tlv_fields {
 618         ($reader: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
 619                 $(
 620                         $crate::_init_tlv_field_var!($field, $fieldty);
 621                 )*
 622
 623                 $crate::read_tlv_fields!($reader, {
 624                         $(($type, $field, $fieldty)),*
 625                 });
 626         }
 627 }
 628
 629 /// Implements [`Readable`]/[`Writeable`] for a struct storing it as a set of TLVs
 630 /// If `$fieldty` is `required`, then `$field` is a required field that is not an Option nor a Vec.
 631 /// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
 632 /// If `$fieldty` is `option`, then `$field` is optional field.
 633 /// If `$fieldty` is `vec_type`, then `$field` is a Vec, which needs to have its individual elements serialized.
 634 ///
 635 /// For example,
 636 /// ```
 637 /// # use lightning::impl_writeable_tlv_based;
 638 /// struct LightningMessage {
 639 ///     tlv_integer: u32,
 640 ///     tlv_default_integer: u32,
 641 ///     tlv_optional_integer: Option<u32>,
 642 ///     tlv_vec_type_integer: Vec<u32>,
 643 /// }
 644 ///
 645 /// impl_writeable_tlv_based!(LightningMessage, {
 646 ///     (0, tlv_integer, required),
 647 ///     (1, tlv_default_integer, (default_value, 7)),
 648 ///     (2, tlv_optional_integer, option),
 649 ///     (3, tlv_vec_type_integer, vec_type),
 650 /// });
 651 /// ```
 652 ///
 653 /// [`Readable`]: crate::util::ser::Readable
 654 /// [`Writeable`]: crate::util::ser::Writeable
 655 #[macro_export]
 656 macro_rules! impl_writeable_tlv_based {
 657         ($st: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
 658                 impl $crate::util::ser::Writeable for $st {
 659                         fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
 660                                 $crate::write_tlv_fields!(writer, {
 661                                         $(($type, self.$field, $fieldty)),*
 662                                 });
 663                                 Ok(())
 664                         }
 665
 666                         #[inline]
 667                         fn serialized_length(&self) -> usize {
 668                                 use $crate::util::ser::BigSize;
 669                                 let len = {
 670                                         #[allow(unused_mut)]
 671                                         let mut len = $crate::util::ser::LengthCalculatingWriter(0);
 672                                         $(
 673                                                 $crate::_get_varint_length_prefixed_tlv_length!(len, $type, self.$field, $fieldty);
 674                                         )*
 675                                         len.0
 676                                 };
 677                                 let mut len_calc = $crate::util::ser::LengthCalculatingWriter(0);
 678                                 BigSize(len as u64).write(&mut len_calc).expect("No in-memory data may fail to serialize");
 679                                 len + len_calc.0
 680                         }
 681                 }
 682
 683                 impl $crate::util::ser::Readable for $st {
 684                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 685                                 $crate::_init_and_read_tlv_fields!(reader, {
 686                                         $(($type, $field, $fieldty)),*
 687                                 });
 688                                 Ok(Self {
 689                                         $(
 690                                                 $field: $crate::_init_tlv_based_struct_field!($field, $fieldty)
 691                                         ),*
 692                                 })
 693                         }
 694                 }
 695         }
 696 }
 697
 698 /// Defines a struct for a TLV stream and a similar struct using references for non-primitive types,
 699 /// implementing [`Readable`] for the former and [`Writeable`] for the latter. Useful as an
 700 /// intermediary format when reading or writing a type encoded as a TLV stream. Note that each field
 701 /// representing a TLV record has its type wrapped with an [`Option`]. A tuple consisting of a type
 702 /// and a serialization wrapper may be given in place of a type when custom serialization is
 703 /// required.
 704 ///
 705 /// [`Readable`]: crate::util::ser::Readable
 706 /// [`Writeable`]: crate::util::ser::Writeable
 707 macro_rules! tlv_stream {
 708         ($name:ident, $nameref:ident, $range:expr, {
 709                 $(($type:expr, $field:ident : $fieldty:tt)),* $(,)*
 710         }) => {
 711                 #[derive(Debug)]
 712                 pub(super) struct $name {
 713                         $(
 714                                 pub(super) $field: Option<tlv_record_type!($fieldty)>,
 715                         )*
 716                 }
 717
 718                 #[derive(Debug, PartialEq)]
 719                 pub(super) struct $nameref<'a> {
 720                         $(
 721                                 pub(super) $field: Option<tlv_record_ref_type!($fieldty)>,
 722                         )*
 723                 }
 724
 725                 impl<'a> $crate::util::ser::Writeable for $nameref<'a> {
 726                         fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
 727                                 encode_tlv_stream!(writer, {
 728                                         $(($type, self.$field, (option, encoding: $fieldty))),*
 729                                 });
 730                                 Ok(())
 731                         }
 732                 }
 733
 734                 impl $crate::util::ser::SeekReadable for $name {
 735                         fn read<R: $crate::io::Read + $crate::io::Seek>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 736                                 $(
 737                                         _init_tlv_field_var!($field, option);
 738                                 )*
 739                                 let rewind = |cursor: &mut R, offset: usize| {
 740                                         cursor.seek($crate::io::SeekFrom::Current(-(offset as i64))).expect("");
 741                                 };
 742                                 _decode_tlv_stream_range!(reader, $range, rewind, {
 743                                         $(($type, $field, (option, encoding: $fieldty))),*
 744                                 });
 745
 746                                 Ok(Self {
 747                                         $(
 748                                                 $field: $field
 749                                         ),*
 750                                 })
 751                         }
 752                 }
 753         }
 754 }
 755
 756 macro_rules! tlv_record_type {
 757         (($type:ty, $wrapper:ident)) => { $type };
 758         ($type:ty) => { $type };
 759 }
 760
 761 macro_rules! tlv_record_ref_type {
 762         (char) => { char };
 763         (u8) => { u8 };
 764         ((u16, $wrapper: ident)) => { u16 };
 765         ((u32, $wrapper: ident)) => { u32 };
 766         ((u64, $wrapper: ident)) => { u64 };
 767         (($type:ty, $wrapper:ident)) => { &'a $type };
 768         ($type:ty) => { &'a $type };
 769 }
 770
 771 macro_rules! _impl_writeable_tlv_based_enum_common {
 772         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
 773                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 774         ),* $(,)*;
 775         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*) => {
 776                 impl $crate::util::ser::Writeable for $st {
 777                         fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
 778                                 match self {
 779                                         $($st::$variant_name { $(ref $field),* } => {
 780                                                 let id: u8 = $variant_id;
 781                                                 id.write(writer)?;
 782                                                 write_tlv_fields!(writer, {
 783                                                         $(($type, *$field, $fieldty)),*
 784                                                 });
 785                                         }),*
 786                                         $($st::$tuple_variant_name (ref field) => {
 787                                                 let id: u8 = $tuple_variant_id;
 788                                                 id.write(writer)?;
 789                                                 field.write(writer)?;
 790                                         }),*
 791                                 }
 792                                 Ok(())
 793                         }
 794                 }
 795         }
 796 }
 797
 798 /// Implement [`MaybeReadable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and
 799 /// tuple variants stored directly.
 800 ///
 801 /// This is largely identical to [`impl_writeable_tlv_based_enum`], except that odd variants will
 802 /// return `Ok(None)` instead of `Err(`[`DecodeError::UnknownRequiredFeature`]`)`. It should generally be preferred
 803 /// when [`MaybeReadable`] is practical instead of just [`Readable`] as it provides an upgrade path for
 804 /// new variants to be added which are simply ignored by existing clients.
 805 ///
 806 /// [`MaybeReadable`]: crate::util::ser::MaybeReadable
 807 /// [`Writeable`]: crate::util::ser::Writeable
 808 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
 809 /// [`Readable`]: crate::util::ser::Readable
 810 macro_rules! impl_writeable_tlv_based_enum_upgradable {
 811         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
 812                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 813         ),* $(,)*
 814         $(;
 815         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*)*) => {
 816                 _impl_writeable_tlv_based_enum_common!($st,
 817                         $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
 818                         $($(($tuple_variant_id, $tuple_variant_name)),*)*);
 819
 820                 impl $crate::util::ser::MaybeReadable for $st {
 821                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Option<Self>, $crate::ln::msgs::DecodeError> {
 822                                 let id: u8 = $crate::util::ser::Readable::read(reader)?;
 823                                 match id {
 824                                         $($variant_id => {
 825                                                 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
 826                                                 // in the same function body. Instead, we define a closure and call it.
 827                                                 let f = || {
 828                                                         _init_and_read_tlv_fields!(reader, {
 829                                                                 $(($type, $field, $fieldty)),*
 830                                                         });
 831                                                         Ok(Some($st::$variant_name {
 832                                                                 $(
 833                                                                         $field: _init_tlv_based_struct_field!($field, $fieldty)
 834                                                                 ),*
 835                                                         }))
 836                                                 };
 837                                                 f()
 838                                         }),*
 839                                         $($($tuple_variant_id => {
 840                                                 Ok(Some($st::$tuple_variant_name(Readable::read(reader)?)))
 841                                         }),*)*
 842                                         _ if id % 2 == 1 => Ok(None),
 843                                         _ => Err(DecodeError::UnknownRequiredFeature),
 844                                 }
 845                         }
 846                 }
 847
 848         }
 849 }
 850
 851 /// Implement [`Readable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and tuple
 852 /// variants stored directly.
 853 /// The format is, for example
 854 /// impl_writeable_tlv_based_enum!(EnumName,
 855 ///   (0, StructVariantA) => {(0, required_variant_field, required), (1, optional_variant_field, option)},
 856 ///   (1, StructVariantB) => {(0, variant_field_a, required), (1, variant_field_b, required), (2, variant_vec_field, vec_type)};
 857 ///   (2, TupleVariantA), (3, TupleVariantB),
 858 /// );
 859 /// The type is written as a single byte, followed by any variant data.
 860 /// Attempts to read an unknown type byte result in [`DecodeError::UnknownRequiredFeature`].
 861 ///
 862 /// [`Readable`]: crate::util::ser::Readable
 863 /// [`Writeable`]: crate::util::ser::Writeable
 864 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
 865 macro_rules! impl_writeable_tlv_based_enum {
 866         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
 867                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 868         ),* $(,)*;
 869         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*) => {
 870                 _impl_writeable_tlv_based_enum_common!($st,
 871                         $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
 872                         $(($tuple_variant_id, $tuple_variant_name)),*);
 873
 874                 impl $crate::util::ser::Readable for $st {
 875                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 876                                 let id: u8 = $crate::util::ser::Readable::read(reader)?;
 877                                 match id {
 878                                         $($variant_id => {
 879                                                 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
 880                                                 // in the same function body. Instead, we define a closure and call it.
 881                                                 let f = || {
 882                                                         _init_and_read_tlv_fields!(reader, {
 883                                                                 $(($type, $field, $fieldty)),*
 884                                                         });
 885                                                         Ok($st::$variant_name {
 886                                                                 $(
 887                                                                         $field: _init_tlv_based_struct_field!($field, $fieldty)
 888                                                                 ),*
 889                                                         })
 890                                                 };
 891                                                 f()
 892                                         }),*
 893                                         $($tuple_variant_id => {
 894                                                 Ok($st::$tuple_variant_name(Readable::read(reader)?))
 895                                         }),*
 896                                         _ => {
 897                                                 Err($crate::ln::msgs::DecodeError::UnknownRequiredFeature)
 898                                         },
 899                                 }
 900                         }
 901                 }
 902         }
 903 }
 904
 905 #[cfg(test)]
 906 mod tests {
 907         use crate::io::{self, Cursor};
 908         use crate::prelude::*;
 909         use crate::ln::msgs::DecodeError;
 910         use crate::util::ser::{Writeable, HighZeroBytesDroppedBigSize, VecWriter};
 911         use bitcoin::secp256k1::PublicKey;
 912
 913         // The BOLT TLV test cases don't include any tests which use our "required-value" logic since
 914         // the encoding layer in the BOLTs has no such concept, though it makes our macros easier to
 915         // work with so they're baked into the decoder. Thus, we have a few additional tests below
 916         fn tlv_reader(s: &[u8]) -> Result<(u64, u32, Option<u32>), DecodeError> {
 917                 let mut s = Cursor::new(s);
 918                 let mut a: u64 = 0;
 919                 let mut b: u32 = 0;
 920                 let mut c: Option<u32> = None;
 921                 decode_tlv_stream!(&mut s, {(2, a, required), (3, b, required), (4, c, option)});
 922                 Ok((a, b, c))
 923         }
 924
 925         #[test]
 926         fn tlv_v_short_read() {
 927                 // We only expect a u32 for type 3 (which we are given), but the L says its 8 bytes.
 928                 if let Err(DecodeError::ShortRead) = tlv_reader(&::hex::decode(
 929                                 concat!("0100", "0208deadbeef1badbeef", "0308deadbeef")
 930                                 ).unwrap()[..]) {
 931                 } else { panic!(); }
 932         }
 933
 934         #[test]
 935         fn tlv_types_out_of_order() {
 936                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 937                                 concat!("0100", "0304deadbeef", "0208deadbeef1badbeef")
 938                                 ).unwrap()[..]) {
 939                 } else { panic!(); }
 940                 // ...even if its some field we don't understand
 941                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 942                                 concat!("0208deadbeef1badbeef", "0100", "0304deadbeef")
 943                                 ).unwrap()[..]) {
 944                 } else { panic!(); }
 945         }
 946
 947         #[test]
 948         fn tlv_req_type_missing_or_extra() {
 949                 // It's also bad if they included even fields we don't understand
 950                 if let Err(DecodeError::UnknownRequiredFeature) = tlv_reader(&::hex::decode(
 951                                 concat!("0100", "0208deadbeef1badbeef", "0304deadbeef", "0600")
 952                                 ).unwrap()[..]) {
 953                 } else { panic!(); }
 954                 // ... or if they're missing fields we need
 955                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 956                                 concat!("0100", "0208deadbeef1badbeef")
 957                                 ).unwrap()[..]) {
 958                 } else { panic!(); }
 959                 // ... even if that field is even
 960                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 961                                 concat!("0304deadbeef", "0500")
 962                                 ).unwrap()[..]) {
 963                 } else { panic!(); }
 964         }
 965
 966         #[test]
 967         fn tlv_simple_good_cases() {
 968                 assert_eq!(tlv_reader(&::hex::decode(
 969                                 concat!("0208deadbeef1badbeef", "03041bad1dea")
 970                                 ).unwrap()[..]).unwrap(),
 971                         (0xdeadbeef1badbeef, 0x1bad1dea, None));
 972                 assert_eq!(tlv_reader(&::hex::decode(
 973                                 concat!("0208deadbeef1badbeef", "03041bad1dea", "040401020304")
 974                                 ).unwrap()[..]).unwrap(),
 975                         (0xdeadbeef1badbeef, 0x1bad1dea, Some(0x01020304)));
 976         }
 977
 978         // BOLT TLV test cases
 979         fn tlv_reader_n1(s: &[u8]) -> Result<(Option<HighZeroBytesDroppedBigSize<u64>>, Option<u64>, Option<(PublicKey, u64, u64)>, Option<u16>), DecodeError> {
 980                 let mut s = Cursor::new(s);
 981                 let mut tlv1: Option<HighZeroBytesDroppedBigSize<u64>> = None;
 982                 let mut tlv2: Option<u64> = None;
 983                 let mut tlv3: Option<(PublicKey, u64, u64)> = None;
 984                 let mut tlv4: Option<u16> = None;
 985                 decode_tlv_stream!(&mut s, {(1, tlv1, option), (2, tlv2, option), (3, tlv3, option), (254, tlv4, option)});
 986                 Ok((tlv1, tlv2, tlv3, tlv4))
 987         }
 988
 989         #[test]
 990         fn bolt_tlv_bogus_stream() {
 991                 macro_rules! do_test {
 992                         ($stream: expr, $reason: ident) => {
 993                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
 994                                 } else { panic!(); }
 995                         }
 996                 }
 997
 998                 // TLVs from the BOLT test cases which should not decode as either n1 or n2
 999                 do_test!(concat!("fd01"), ShortRead);
1000                 do_test!(concat!("fd0001", "00"), InvalidValue);
1001                 do_test!(concat!("fd0101"), ShortRead);
1002                 do_test!(concat!("0f", "fd"), ShortRead);
1003                 do_test!(concat!("0f", "fd26"), ShortRead);
1004                 do_test!(concat!("0f", "fd2602"), ShortRead);
1005                 do_test!(concat!("0f", "fd0001", "00"), InvalidValue);
1006                 do_test!(concat!("0f", "fd0201", "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), ShortRead);
1007
1008                 do_test!(concat!("12", "00"), UnknownRequiredFeature);
1009                 do_test!(concat!("fd0102", "00"), UnknownRequiredFeature);
1010                 do_test!(concat!("fe01000002", "00"), UnknownRequiredFeature);
1011                 do_test!(concat!("ff0100000000000002", "00"), UnknownRequiredFeature);
1012         }
1013
1014         #[test]
1015         fn bolt_tlv_bogus_n1_stream() {
1016                 macro_rules! do_test {
1017                         ($stream: expr, $reason: ident) => {
1018                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1019                                 } else { panic!(); }
1020                         }
1021                 }
1022
1023                 // TLVs from the BOLT test cases which should not decode as n1
1024                 do_test!(concat!("01", "09", "ffffffffffffffffff"), InvalidValue);
1025                 do_test!(concat!("01", "01", "00"), InvalidValue);
1026                 do_test!(concat!("01", "02", "0001"), InvalidValue);
1027                 do_test!(concat!("01", "03", "000100"), InvalidValue);
1028                 do_test!(concat!("01", "04", "00010000"), InvalidValue);
1029                 do_test!(concat!("01", "05", "0001000000"), InvalidValue);
1030                 do_test!(concat!("01", "06", "000100000000"), InvalidValue);
1031                 do_test!(concat!("01", "07", "00010000000000"), InvalidValue);
1032                 do_test!(concat!("01", "08", "0001000000000000"), InvalidValue);
1033                 do_test!(concat!("02", "07", "01010101010101"), ShortRead);
1034                 do_test!(concat!("02", "09", "010101010101010101"), InvalidValue);
1035                 do_test!(concat!("03", "21", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb"), ShortRead);
1036                 do_test!(concat!("03", "29", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001"), ShortRead);
1037                 do_test!(concat!("03", "30", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb000000000000000100000000000001"), ShortRead);
1038                 do_test!(concat!("03", "31", "043da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"), InvalidValue);
1039                 do_test!(concat!("03", "32", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001000000000000000001"), InvalidValue);
1040                 do_test!(concat!("fd00fe", "00"), ShortRead);
1041                 do_test!(concat!("fd00fe", "01", "01"), ShortRead);
1042                 do_test!(concat!("fd00fe", "03", "010101"), InvalidValue);
1043                 do_test!(concat!("00", "00"), UnknownRequiredFeature);
1044
1045                 do_test!(concat!("02", "08", "0000000000000226", "01", "01", "2a"), InvalidValue);
1046                 do_test!(concat!("02", "08", "0000000000000231", "02", "08", "0000000000000451"), InvalidValue);
1047                 do_test!(concat!("1f", "00", "0f", "01", "2a"), InvalidValue);
1048                 do_test!(concat!("1f", "00", "1f", "01", "2a"), InvalidValue);
1049
1050                 // The last BOLT test modified to not require creating a new decoder for one trivial test.
1051                 do_test!(concat!("ffffffffffffffffff", "00", "01", "00"), InvalidValue);
1052         }
1053
1054         #[test]
1055         fn bolt_tlv_valid_n1_stream() {
1056                 macro_rules! do_test {
1057                         ($stream: expr, $tlv1: expr, $tlv2: expr, $tlv3: expr, $tlv4: expr) => {
1058                                 if let Ok((tlv1, tlv2, tlv3, tlv4)) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1059                                         assert_eq!(tlv1.map(|v| v.0), $tlv1);
1060                                         assert_eq!(tlv2, $tlv2);
1061                                         assert_eq!(tlv3, $tlv3);
1062                                         assert_eq!(tlv4, $tlv4);
1063                                 } else { panic!(); }
1064                         }
1065                 }
1066
1067                 do_test!(concat!(""), None, None, None, None);
1068                 do_test!(concat!("21", "00"), None, None, None, None);
1069                 do_test!(concat!("fd0201", "00"), None, None, None, None);
1070                 do_test!(concat!("fd00fd", "00"), None, None, None, None);
1071                 do_test!(concat!("fd00ff", "00"), None, None, None, None);
1072                 do_test!(concat!("fe02000001", "00"), None, None, None, None);
1073                 do_test!(concat!("ff0200000000000001", "00"), None, None, None, None);
1074
1075                 do_test!(concat!("01", "00"), Some(0), None, None, None);
1076                 do_test!(concat!("01", "01", "01"), Some(1), None, None, None);
1077                 do_test!(concat!("01", "02", "0100"), Some(256), None, None, None);
1078                 do_test!(concat!("01", "03", "010000"), Some(65536), None, None, None);
1079                 do_test!(concat!("01", "04", "01000000"), Some(16777216), None, None, None);
1080                 do_test!(concat!("01", "05", "0100000000"), Some(4294967296), None, None, None);
1081                 do_test!(concat!("01", "06", "010000000000"), Some(1099511627776), None, None, None);
1082                 do_test!(concat!("01", "07", "01000000000000"), Some(281474976710656), None, None, None);
1083                 do_test!(concat!("01", "08", "0100000000000000"), Some(72057594037927936), None, None, None);
1084                 do_test!(concat!("02", "08", "0000000000000226"), None, Some((0 << 30) | (0 << 5) | (550 << 0)), None, None);
1085                 do_test!(concat!("03", "31", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"),
1086                         None, None, Some((
1087                                 PublicKey::from_slice(&::hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]).unwrap(), 1, 2)),
1088                         None);
1089                 do_test!(concat!("fd00fe", "02", "0226"), None, None, None, Some(550));
1090         }
1091
1092         fn do_simple_test_tlv_write() -> Result<(), io::Error> {
1093                 let mut stream = VecWriter(Vec::new());
1094
1095                 stream.0.clear();
1096                 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, 1u8, required), (42, None::<u64>, option)});
1097                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1098
1099                 stream.0.clear();
1100                 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, Some(1u8), option)});
1101                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1102
1103                 stream.0.clear();
1104                 _encode_varint_length_prefixed_tlv!(&mut stream, {(4, 0xabcdu16, required), (42, None::<u64>, option)});
1105                 assert_eq!(stream.0, ::hex::decode("040402abcd").unwrap());
1106
1107                 stream.0.clear();
1108                 _encode_varint_length_prefixed_tlv!(&mut stream, {(42, None::<u64>, option), (0xff, 0xabcdu16, required)});
1109                 assert_eq!(stream.0, ::hex::decode("06fd00ff02abcd").unwrap());
1110
1111                 stream.0.clear();
1112                 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, 1u64, required), (42, None::<u64>, option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1113                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1114
1115                 stream.0.clear();
1116                 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, Some(1u64), option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1117                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1118
1119                 Ok(())
1120         }
1121
1122         #[test]
1123         fn simple_test_tlv_write() {
1124                 do_simple_test_tlv_write().unwrap();
1125         }
1126 }