_ 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 ///
 505 /// $this_version represents a unique version of a type. Incremented whenever the type's
 506 /// serialization format has changed or has a new interpretation. Used by a type's reader to
 507 /// determine how to interpret fields or if it can understand a serialized object.
 508 ///
 509 /// $min_version_that_can_read_this is the minimum reader version which can understand this
 510 /// serialized object. Previous versions will simply err with a [`DecodeError::UnknownVersion`].
 511 ///
 512 /// Updates to either `$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(|_| $crate::ln::msgs::DecodeError::ShortRead)?;
 566         } }
 567 }
 568
 569 /// Initializes the struct fields.
 570 ///
 571 /// This is exported for use by other exported macros, do not use directly.
 572 #[doc(hidden)]
 573 #[macro_export]
 574 macro_rules! _init_tlv_based_struct_field {
 575         ($field: ident, (default_value, $default: expr)) => {
 576                 $field.0.unwrap()
 577         };
 578         ($field: ident, (static_value, $value: expr)) => {
 579                 $field
 580         };
 581         ($field: ident, option) => {
 582                 $field
 583         };
 584         ($field: ident, required) => {
 585                 $field.0.unwrap()
 586         };
 587         ($field: ident, vec_type) => {
 588                 $field.unwrap()
 589         };
 590 }
 591
 592 /// Initializes the variable we are going to read the TLV into.
 593 ///
 594 /// This is exported for use by other exported macros, do not use directly.
 595 #[doc(hidden)]
 596 #[macro_export]
 597 macro_rules! _init_tlv_field_var {
 598         ($field: ident, (default_value, $default: expr)) => {
 599                 let mut $field = $crate::util::ser::OptionDeserWrapper(None);
 600         };
 601         ($field: ident, (static_value, $value: expr)) => {
 602                 let $field;
 603         };
 604         ($field: ident, required) => {
 605                 let mut $field = $crate::util::ser::OptionDeserWrapper(None);
 606         };
 607         ($field: ident, vec_type) => {
 608                 let mut $field = Some(Vec::new());
 609         };
 610         ($field: ident, option) => {
 611                 let mut $field = None;
 612         };
 613 }
 614
 615 /// Equivalent to running [`_init_tlv_field_var`] then [`read_tlv_fields`].
 616 ///
 617 /// This is exported for use by other exported macros, do not use directly.
 618 #[doc(hidden)]
 619 #[macro_export]
 620 macro_rules! _init_and_read_tlv_fields {
 621         ($reader: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
 622                 $(
 623                         $crate::_init_tlv_field_var!($field, $fieldty);
 624                 )*
 625
 626                 $crate::read_tlv_fields!($reader, {
 627                         $(($type, $field, $fieldty)),*
 628                 });
 629         }
 630 }
 631
 632 /// Implements [`Readable`]/[`Writeable`] for a struct storing it as a set of TLVs
 633 /// If `$fieldty` is `required`, then `$field` is a required field that is not an Option nor a Vec.
 634 /// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
 635 /// If `$fieldty` is `option`, then `$field` is optional field.
 636 /// If `$fieldty` is `vec_type`, then `$field` is a Vec, which needs to have its individual elements serialized.
 637 ///
 638 /// For example,
 639 /// ```
 640 /// # use lightning::impl_writeable_tlv_based;
 641 /// struct LightningMessage {
 642 ///     tlv_integer: u32,
 643 ///     tlv_default_integer: u32,
 644 ///     tlv_optional_integer: Option<u32>,
 645 ///     tlv_vec_type_integer: Vec<u32>,
 646 /// }
 647 ///
 648 /// impl_writeable_tlv_based!(LightningMessage, {
 649 ///     (0, tlv_integer, required),
 650 ///     (1, tlv_default_integer, (default_value, 7)),
 651 ///     (2, tlv_optional_integer, option),
 652 ///     (3, tlv_vec_type_integer, vec_type),
 653 /// });
 654 /// ```
 655 ///
 656 /// [`Readable`]: crate::util::ser::Readable
 657 /// [`Writeable`]: crate::util::ser::Writeable
 658 #[macro_export]
 659 macro_rules! impl_writeable_tlv_based {
 660         ($st: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
 661                 impl $crate::util::ser::Writeable for $st {
 662                         fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
 663                                 $crate::write_tlv_fields!(writer, {
 664                                         $(($type, self.$field, $fieldty)),*
 665                                 });
 666                                 Ok(())
 667                         }
 668
 669                         #[inline]
 670                         fn serialized_length(&self) -> usize {
 671                                 use $crate::util::ser::BigSize;
 672                                 let len = {
 673                                         #[allow(unused_mut)]
 674                                         let mut len = $crate::util::ser::LengthCalculatingWriter(0);
 675                                         $(
 676                                                 $crate::_get_varint_length_prefixed_tlv_length!(len, $type, self.$field, $fieldty);
 677                                         )*
 678                                         len.0
 679                                 };
 680                                 let mut len_calc = $crate::util::ser::LengthCalculatingWriter(0);
 681                                 BigSize(len as u64).write(&mut len_calc).expect("No in-memory data may fail to serialize");
 682                                 len + len_calc.0
 683                         }
 684                 }
 685
 686                 impl $crate::util::ser::Readable for $st {
 687                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 688                                 $crate::_init_and_read_tlv_fields!(reader, {
 689                                         $(($type, $field, $fieldty)),*
 690                                 });
 691                                 Ok(Self {
 692                                         $(
 693                                                 $field: $crate::_init_tlv_based_struct_field!($field, $fieldty)
 694                                         ),*
 695                                 })
 696                         }
 697                 }
 698         }
 699 }
 700
 701 /// Defines a struct for a TLV stream and a similar struct using references for non-primitive types,
 702 /// implementing [`Readable`] for the former and [`Writeable`] for the latter. Useful as an
 703 /// intermediary format when reading or writing a type encoded as a TLV stream. Note that each field
 704 /// representing a TLV record has its type wrapped with an [`Option`]. A tuple consisting of a type
 705 /// and a serialization wrapper may be given in place of a type when custom serialization is
 706 /// required.
 707 ///
 708 /// [`Readable`]: crate::util::ser::Readable
 709 /// [`Writeable`]: crate::util::ser::Writeable
 710 macro_rules! tlv_stream {
 711         ($name:ident, $nameref:ident, $range:expr, {
 712                 $(($type:expr, $field:ident : $fieldty:tt)),* $(,)*
 713         }) => {
 714                 #[derive(Debug)]
 715                 pub(super) struct $name {
 716                         $(
 717                                 pub(super) $field: Option<tlv_record_type!($fieldty)>,
 718                         )*
 719                 }
 720
 721                 #[derive(Debug, PartialEq)]
 722                 pub(super) struct $nameref<'a> {
 723                         $(
 724                                 pub(super) $field: Option<tlv_record_ref_type!($fieldty)>,
 725                         )*
 726                 }
 727
 728                 impl<'a> $crate::util::ser::Writeable for $nameref<'a> {
 729                         fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
 730                                 encode_tlv_stream!(writer, {
 731                                         $(($type, self.$field, (option, encoding: $fieldty))),*
 732                                 });
 733                                 Ok(())
 734                         }
 735                 }
 736
 737                 impl $crate::util::ser::SeekReadable for $name {
 738                         fn read<R: $crate::io::Read + $crate::io::Seek>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 739                                 $(
 740                                         _init_tlv_field_var!($field, option);
 741                                 )*
 742                                 let rewind = |cursor: &mut R, offset: usize| {
 743                                         cursor.seek($crate::io::SeekFrom::Current(-(offset as i64))).expect("");
 744                                 };
 745                                 _decode_tlv_stream_range!(reader, $range, rewind, {
 746                                         $(($type, $field, (option, encoding: $fieldty))),*
 747                                 });
 748
 749                                 Ok(Self {
 750                                         $(
 751                                                 $field: $field
 752                                         ),*
 753                                 })
 754                         }
 755                 }
 756         }
 757 }
 758
 759 macro_rules! tlv_record_type {
 760         (($type:ty, $wrapper:ident)) => { $type };
 761         ($type:ty) => { $type };
 762 }
 763
 764 macro_rules! tlv_record_ref_type {
 765         (char) => { char };
 766         (u8) => { u8 };
 767         ((u16, $wrapper: ident)) => { u16 };
 768         ((u32, $wrapper: ident)) => { u32 };
 769         ((u64, $wrapper: ident)) => { u64 };
 770         (($type:ty, $wrapper:ident)) => { &'a $type };
 771         ($type:ty) => { &'a $type };
 772 }
 773
 774 macro_rules! _impl_writeable_tlv_based_enum_common {
 775         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
 776                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 777         ),* $(,)*;
 778         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*) => {
 779                 impl $crate::util::ser::Writeable for $st {
 780                         fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
 781                                 match self {
 782                                         $($st::$variant_name { $(ref $field),* } => {
 783                                                 let id: u8 = $variant_id;
 784                                                 id.write(writer)?;
 785                                                 write_tlv_fields!(writer, {
 786                                                         $(($type, *$field, $fieldty)),*
 787                                                 });
 788                                         }),*
 789                                         $($st::$tuple_variant_name (ref field) => {
 790                                                 let id: u8 = $tuple_variant_id;
 791                                                 id.write(writer)?;
 792                                                 field.write(writer)?;
 793                                         }),*
 794                                 }
 795                                 Ok(())
 796                         }
 797                 }
 798         }
 799 }
 800
 801 /// Implement [`Readable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and tuple
 802 /// variants stored directly.
 803 /// The format is, for example
 804 /// ```ignore
 805 /// impl_writeable_tlv_based_enum!(EnumName,
 806 ///   (0, StructVariantA) => {(0, required_variant_field, required), (1, optional_variant_field, option)},
 807 ///   (1, StructVariantB) => {(0, variant_field_a, required), (1, variant_field_b, required), (2, variant_vec_field, vec_type)};
 808 ///   (2, TupleVariantA), (3, TupleVariantB),
 809 /// );
 810 /// ```
 811 /// The type is written as a single byte, followed by any variant data.
 812 /// Attempts to read an unknown type byte result in [`DecodeError::UnknownRequiredFeature`].
 813 ///
 814 /// [`Readable`]: crate::util::ser::Readable
 815 /// [`Writeable`]: crate::util::ser::Writeable
 816 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
 817 #[macro_export]
 818 macro_rules! impl_writeable_tlv_based_enum {
 819         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
 820                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 821         ),* $(,)*;
 822         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*) => {
 823                 _impl_writeable_tlv_based_enum_common!($st,
 824                         $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
 825                         $(($tuple_variant_id, $tuple_variant_name)),*);
 826
 827                 impl $crate::util::ser::Readable for $st {
 828                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 829                                 let id: u8 = $crate::util::ser::Readable::read(reader)?;
 830                                 match id {
 831                                         $($variant_id => {
 832                                                 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
 833                                                 // in the same function body. Instead, we define a closure and call it.
 834                                                 let f = || {
 835                                                         _init_and_read_tlv_fields!(reader, {
 836                                                                 $(($type, $field, $fieldty)),*
 837                                                         });
 838                                                         Ok($st::$variant_name {
 839                                                                 $(
 840                                                                         $field: _init_tlv_based_struct_field!($field, $fieldty)
 841                                                                 ),*
 842                                                         })
 843                                                 };
 844                                                 f()
 845                                         }),*
 846                                         $($tuple_variant_id => {
 847                                                 Ok($st::$tuple_variant_name(Readable::read(reader)?))
 848                                         }),*
 849                                         _ => {
 850                                                 Err($crate::ln::msgs::DecodeError::UnknownRequiredFeature)
 851                                         },
 852                                 }
 853                         }
 854                 }
 855         }
 856 }
 857
 858 /// Implement [`MaybeReadable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and
 859 /// tuple variants stored directly.
 860 ///
 861 /// This is largely identical to [`impl_writeable_tlv_based_enum`], except that odd variants will
 862 /// return `Ok(None)` instead of `Err(`[`DecodeError::UnknownRequiredFeature`]`)`. It should generally be preferred
 863 /// when [`MaybeReadable`] is practical instead of just [`Readable`] as it provides an upgrade path for
 864 /// new variants to be added which are simply ignored by existing clients.
 865 ///
 866 /// [`MaybeReadable`]: crate::util::ser::MaybeReadable
 867 /// [`Writeable`]: crate::util::ser::Writeable
 868 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
 869 /// [`Readable`]: crate::util::ser::Readable
 870 #[macro_export]
 871 macro_rules! impl_writeable_tlv_based_enum_upgradable {
 872         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
 873                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 874         ),* $(,)*
 875         $(;
 876         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*)*) => {
 877                 _impl_writeable_tlv_based_enum_common!($st,
 878                         $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
 879                         $($(($tuple_variant_id, $tuple_variant_name)),*)*);
 880
 881                 impl $crate::util::ser::MaybeReadable for $st {
 882                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Option<Self>, $crate::ln::msgs::DecodeError> {
 883                                 let id: u8 = $crate::util::ser::Readable::read(reader)?;
 884                                 match id {
 885                                         $($variant_id => {
 886                                                 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
 887                                                 // in the same function body. Instead, we define a closure and call it.
 888                                                 let f = || {
 889                                                         _init_and_read_tlv_fields!(reader, {
 890                                                                 $(($type, $field, $fieldty)),*
 891                                                         });
 892                                                         Ok(Some($st::$variant_name {
 893                                                                 $(
 894                                                                         $field: _init_tlv_based_struct_field!($field, $fieldty)
 895                                                                 ),*
 896                                                         }))
 897                                                 };
 898                                                 f()
 899                                         }),*
 900                                         $($($tuple_variant_id => {
 901                                                 Ok(Some($st::$tuple_variant_name(Readable::read(reader)?)))
 902                                         }),*)*
 903                                         _ if id % 2 == 1 => Ok(None),
 904                                         _ => Err(DecodeError::UnknownRequiredFeature),
 905                                 }
 906                         }
 907                 }
 908         }
 909 }
 910
 911 #[cfg(test)]
 912 mod tests {
 913         use crate::io::{self, Cursor};
 914         use crate::prelude::*;
 915         use crate::ln::msgs::DecodeError;
 916         use crate::util::ser::{Writeable, HighZeroBytesDroppedBigSize, VecWriter};
 917         use bitcoin::secp256k1::PublicKey;
 918
 919         // The BOLT TLV test cases don't include any tests which use our "required-value" logic since
 920         // the encoding layer in the BOLTs has no such concept, though it makes our macros easier to
 921         // work with so they're baked into the decoder. Thus, we have a few additional tests below
 922         fn tlv_reader(s: &[u8]) -> Result<(u64, u32, Option<u32>), DecodeError> {
 923                 let mut s = Cursor::new(s);
 924                 let mut a: u64 = 0;
 925                 let mut b: u32 = 0;
 926                 let mut c: Option<u32> = None;
 927                 decode_tlv_stream!(&mut s, {(2, a, required), (3, b, required), (4, c, option)});
 928                 Ok((a, b, c))
 929         }
 930
 931         #[test]
 932         fn tlv_v_short_read() {
 933                 // We only expect a u32 for type 3 (which we are given), but the L says its 8 bytes.
 934                 if let Err(DecodeError::ShortRead) = tlv_reader(&::hex::decode(
 935                                 concat!("0100", "0208deadbeef1badbeef", "0308deadbeef")
 936                                 ).unwrap()[..]) {
 937                 } else { panic!(); }
 938         }
 939
 940         #[test]
 941         fn tlv_types_out_of_order() {
 942                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 943                                 concat!("0100", "0304deadbeef", "0208deadbeef1badbeef")
 944                                 ).unwrap()[..]) {
 945                 } else { panic!(); }
 946                 // ...even if its some field we don't understand
 947                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 948                                 concat!("0208deadbeef1badbeef", "0100", "0304deadbeef")
 949                                 ).unwrap()[..]) {
 950                 } else { panic!(); }
 951         }
 952
 953         #[test]
 954         fn tlv_req_type_missing_or_extra() {
 955                 // It's also bad if they included even fields we don't understand
 956                 if let Err(DecodeError::UnknownRequiredFeature) = tlv_reader(&::hex::decode(
 957                                 concat!("0100", "0208deadbeef1badbeef", "0304deadbeef", "0600")
 958                                 ).unwrap()[..]) {
 959                 } else { panic!(); }
 960                 // ... or if they're missing fields we need
 961                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 962                                 concat!("0100", "0208deadbeef1badbeef")
 963                                 ).unwrap()[..]) {
 964                 } else { panic!(); }
 965                 // ... even if that field is even
 966                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 967                                 concat!("0304deadbeef", "0500")
 968                                 ).unwrap()[..]) {
 969                 } else { panic!(); }
 970         }
 971
 972         #[test]
 973         fn tlv_simple_good_cases() {
 974                 assert_eq!(tlv_reader(&::hex::decode(
 975                                 concat!("0208deadbeef1badbeef", "03041bad1dea")
 976                                 ).unwrap()[..]).unwrap(),
 977                         (0xdeadbeef1badbeef, 0x1bad1dea, None));
 978                 assert_eq!(tlv_reader(&::hex::decode(
 979                                 concat!("0208deadbeef1badbeef", "03041bad1dea", "040401020304")
 980                                 ).unwrap()[..]).unwrap(),
 981                         (0xdeadbeef1badbeef, 0x1bad1dea, Some(0x01020304)));
 982         }
 983
 984         // BOLT TLV test cases
 985         fn tlv_reader_n1(s: &[u8]) -> Result<(Option<HighZeroBytesDroppedBigSize<u64>>, Option<u64>, Option<(PublicKey, u64, u64)>, Option<u16>), DecodeError> {
 986                 let mut s = Cursor::new(s);
 987                 let mut tlv1: Option<HighZeroBytesDroppedBigSize<u64>> = None;
 988                 let mut tlv2: Option<u64> = None;
 989                 let mut tlv3: Option<(PublicKey, u64, u64)> = None;
 990                 let mut tlv4: Option<u16> = None;
 991                 decode_tlv_stream!(&mut s, {(1, tlv1, option), (2, tlv2, option), (3, tlv3, option), (254, tlv4, option)});
 992                 Ok((tlv1, tlv2, tlv3, tlv4))
 993         }
 994
 995         #[test]
 996         fn bolt_tlv_bogus_stream() {
 997                 macro_rules! do_test {
 998                         ($stream: expr, $reason: ident) => {
 999                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1000                                 } else { panic!(); }
1001                         }
1002                 }
1003
1004                 // TLVs from the BOLT test cases which should not decode as either n1 or n2
1005                 do_test!(concat!("fd01"), ShortRead);
1006                 do_test!(concat!("fd0001", "00"), InvalidValue);
1007                 do_test!(concat!("fd0101"), ShortRead);
1008                 do_test!(concat!("0f", "fd"), ShortRead);
1009                 do_test!(concat!("0f", "fd26"), ShortRead);
1010                 do_test!(concat!("0f", "fd2602"), ShortRead);
1011                 do_test!(concat!("0f", "fd0001", "00"), InvalidValue);
1012                 do_test!(concat!("0f", "fd0201", "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), ShortRead);
1013
1014                 do_test!(concat!("12", "00"), UnknownRequiredFeature);
1015                 do_test!(concat!("fd0102", "00"), UnknownRequiredFeature);
1016                 do_test!(concat!("fe01000002", "00"), UnknownRequiredFeature);
1017                 do_test!(concat!("ff0100000000000002", "00"), UnknownRequiredFeature);
1018         }
1019
1020         #[test]
1021         fn bolt_tlv_bogus_n1_stream() {
1022                 macro_rules! do_test {
1023                         ($stream: expr, $reason: ident) => {
1024                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1025                                 } else { panic!(); }
1026                         }
1027                 }
1028
1029                 // TLVs from the BOLT test cases which should not decode as n1
1030                 do_test!(concat!("01", "09", "ffffffffffffffffff"), InvalidValue);
1031                 do_test!(concat!("01", "01", "00"), InvalidValue);
1032                 do_test!(concat!("01", "02", "0001"), InvalidValue);
1033                 do_test!(concat!("01", "03", "000100"), InvalidValue);
1034                 do_test!(concat!("01", "04", "00010000"), InvalidValue);
1035                 do_test!(concat!("01", "05", "0001000000"), InvalidValue);
1036                 do_test!(concat!("01", "06", "000100000000"), InvalidValue);
1037                 do_test!(concat!("01", "07", "00010000000000"), InvalidValue);
1038                 do_test!(concat!("01", "08", "0001000000000000"), InvalidValue);
1039                 do_test!(concat!("02", "07", "01010101010101"), ShortRead);
1040                 do_test!(concat!("02", "09", "010101010101010101"), InvalidValue);
1041                 do_test!(concat!("03", "21", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb"), ShortRead);
1042                 do_test!(concat!("03", "29", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001"), ShortRead);
1043                 do_test!(concat!("03", "30", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb000000000000000100000000000001"), ShortRead);
1044                 do_test!(concat!("03", "31", "043da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"), InvalidValue);
1045                 do_test!(concat!("03", "32", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001000000000000000001"), InvalidValue);
1046                 do_test!(concat!("fd00fe", "00"), ShortRead);
1047                 do_test!(concat!("fd00fe", "01", "01"), ShortRead);
1048                 do_test!(concat!("fd00fe", "03", "010101"), InvalidValue);
1049                 do_test!(concat!("00", "00"), UnknownRequiredFeature);
1050
1051                 do_test!(concat!("02", "08", "0000000000000226", "01", "01", "2a"), InvalidValue);
1052                 do_test!(concat!("02", "08", "0000000000000231", "02", "08", "0000000000000451"), InvalidValue);
1053                 do_test!(concat!("1f", "00", "0f", "01", "2a"), InvalidValue);
1054                 do_test!(concat!("1f", "00", "1f", "01", "2a"), InvalidValue);
1055
1056                 // The last BOLT test modified to not require creating a new decoder for one trivial test.
1057                 do_test!(concat!("ffffffffffffffffff", "00", "01", "00"), InvalidValue);
1058         }
1059
1060         #[test]
1061         fn bolt_tlv_valid_n1_stream() {
1062                 macro_rules! do_test {
1063                         ($stream: expr, $tlv1: expr, $tlv2: expr, $tlv3: expr, $tlv4: expr) => {
1064                                 if let Ok((tlv1, tlv2, tlv3, tlv4)) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1065                                         assert_eq!(tlv1.map(|v| v.0), $tlv1);
1066                                         assert_eq!(tlv2, $tlv2);
1067                                         assert_eq!(tlv3, $tlv3);
1068                                         assert_eq!(tlv4, $tlv4);
1069                                 } else { panic!(); }
1070                         }
1071                 }
1072
1073                 do_test!(concat!(""), None, None, None, None);
1074                 do_test!(concat!("21", "00"), None, None, None, None);
1075                 do_test!(concat!("fd0201", "00"), None, None, None, None);
1076                 do_test!(concat!("fd00fd", "00"), None, None, None, None);
1077                 do_test!(concat!("fd00ff", "00"), None, None, None, None);
1078                 do_test!(concat!("fe02000001", "00"), None, None, None, None);
1079                 do_test!(concat!("ff0200000000000001", "00"), None, None, None, None);
1080
1081                 do_test!(concat!("01", "00"), Some(0), None, None, None);
1082                 do_test!(concat!("01", "01", "01"), Some(1), None, None, None);
1083                 do_test!(concat!("01", "02", "0100"), Some(256), None, None, None);
1084                 do_test!(concat!("01", "03", "010000"), Some(65536), None, None, None);
1085                 do_test!(concat!("01", "04", "01000000"), Some(16777216), None, None, None);
1086                 do_test!(concat!("01", "05", "0100000000"), Some(4294967296), None, None, None);
1087                 do_test!(concat!("01", "06", "010000000000"), Some(1099511627776), None, None, None);
1088                 do_test!(concat!("01", "07", "01000000000000"), Some(281474976710656), None, None, None);
1089                 do_test!(concat!("01", "08", "0100000000000000"), Some(72057594037927936), None, None, None);
1090                 do_test!(concat!("02", "08", "0000000000000226"), None, Some((0 << 30) | (0 << 5) | (550 << 0)), None, None);
1091                 do_test!(concat!("03", "31", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"),
1092                         None, None, Some((
1093                                 PublicKey::from_slice(&::hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]).unwrap(), 1, 2)),
1094                         None);
1095                 do_test!(concat!("fd00fe", "02", "0226"), None, None, None, Some(550));
1096         }
1097
1098         fn do_simple_test_tlv_write() -> Result<(), io::Error> {
1099                 let mut stream = VecWriter(Vec::new());
1100
1101                 stream.0.clear();
1102                 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, 1u8, required), (42, None::<u64>, option)});
1103                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1104
1105                 stream.0.clear();
1106                 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, Some(1u8), option)});
1107                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1108
1109                 stream.0.clear();
1110                 _encode_varint_length_prefixed_tlv!(&mut stream, {(4, 0xabcdu16, required), (42, None::<u64>, option)});
1111                 assert_eq!(stream.0, ::hex::decode("040402abcd").unwrap());
1112
1113                 stream.0.clear();
1114                 _encode_varint_length_prefixed_tlv!(&mut stream, {(42, None::<u64>, option), (0xff, 0xabcdu16, required)});
1115                 assert_eq!(stream.0, ::hex::decode("06fd00ff02abcd").unwrap());
1116
1117                 stream.0.clear();
1118                 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, 1u64, required), (42, None::<u64>, option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1119                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1120
1121                 stream.0.clear();
1122                 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, Some(1u64), option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1123                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1124
1125                 Ok(())
1126         }
1127
1128         #[test]
1129         fn simple_test_tlv_write() {
1130                 do_simple_test_tlv_write().unwrap();
1131         }
1132 }