Merge pull request #1951 from wpaulino/remove-get-node-secret
[rust-lightning] / 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, ignorable) => {
43                 $crate::_encode_tlv!($stream, $type, $field, required);
44         };
45         ($stream: expr, $type: expr, $field: expr, (option, encoding: ($fieldty: ty, $encoding: ident))) => {
46                 $crate::_encode_tlv!($stream, $type, $field.map(|f| $encoding(f)), option);
47         };
48         ($stream: expr, $type: expr, $field: expr, (option, encoding: $fieldty: ty)) => {
49                 $crate::_encode_tlv!($stream, $type, $field, option);
50         };
51 }
52
53 /// Panics if the last seen TLV type is not numerically less than the TLV type currently being checked.
54 /// This is exported for use by other exported macros, do not use directly.
55 #[doc(hidden)]
56 #[macro_export]
57 macro_rules! _check_encoded_tlv_order {
58         ($last_type: expr, $type: expr, (static_value, $value: expr)) => { };
59         ($last_type: expr, $type: expr, $fieldty: tt) => {
60                 if let Some(t) = $last_type {
61                         #[allow(unused_comparisons)] // Note that $type may be 0 making the following comparison always false
62                         (debug_assert!(t < $type))
63                 }
64                 $last_type = Some($type);
65         };
66 }
67
68 /// Implements the TLVs serialization part in a [`Writeable`] implementation of a struct.
69 ///
70 /// This should be called inside a method which returns `Result<_, `[`io::Error`]`>`, such as
71 /// [`Writeable::write`]. It will only return an `Err` if the stream `Err`s or [`Writeable::write`]
72 /// on one of the fields `Err`s.
73 ///
74 /// `$stream` must be a `&mut `[`Writer`] which will receive the bytes for each TLV in the stream.
75 ///
76 /// Fields MUST be sorted in `$type`-order.
77 ///
78 /// Note that the lightning TLV requirements require that a single type not appear more than once,
79 /// that TLVs are sorted in type-ascending order, and that any even types be understood by the
80 /// decoder.
81 ///
82 /// Any `option` fields which have a value of `None` will not be serialized at all.
83 ///
84 /// For example,
85 /// ```
86 /// # use lightning::encode_tlv_stream;
87 /// # fn write<W: lightning::util::ser::Writer> (stream: &mut W) -> Result<(), lightning::io::Error> {
88 /// let mut required_value = 0u64;
89 /// let mut optional_value: Option<u64> = None;
90 /// encode_tlv_stream!(stream, {
91 ///     (0, required_value, required),
92 ///     (1, Some(42u64), option),
93 ///     (2, optional_value, option),
94 /// });
95 /// // At this point `required_value` has been written as a TLV of type 0, `42u64` has been written
96 /// // as a TLV of type 1 (indicating the reader may ignore it if it is not understood), and *no*
97 /// // TLV is written with type 2.
98 /// # Ok(())
99 /// # }
100 /// ```
101 ///
102 /// [`Writeable`]: crate::util::ser::Writeable
103 /// [`io::Error`]: crate::io::Error
104 /// [`Writeable::write`]: crate::util::ser::Writeable::write
105 /// [`Writer`]: crate::util::ser::Writer
106 #[macro_export]
107 macro_rules! encode_tlv_stream {
108         ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => { {
109                 #[allow(unused_imports)]
110                 use $crate::{
111                         ln::msgs::DecodeError,
112                         util::ser,
113                         util::ser::BigSize,
114                         util::ser::Writeable,
115                 };
116
117                 $(
118                         $crate::_encode_tlv!($stream, $type, $field, $fieldty);
119                 )*
120
121                 #[allow(unused_mut, unused_variables, unused_assignments)]
122                 #[cfg(debug_assertions)]
123                 {
124                         let mut last_seen: Option<u64> = None;
125                         $(
126                                 $crate::_check_encoded_tlv_order!(last_seen, $type, $fieldty);
127                         )*
128                 }
129         } }
130 }
131
132 /// Adds the length of the serialized field to a [`LengthCalculatingWriter`].
133 /// This is exported for use by other exported macros, do not use directly.
134 ///
135 /// [`LengthCalculatingWriter`]: crate::util::ser::LengthCalculatingWriter
136 #[doc(hidden)]
137 #[macro_export]
138 macro_rules! _get_varint_length_prefixed_tlv_length {
139         ($len: expr, $type: expr, $field: expr, (default_value, $default: expr)) => {
140                 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
141         };
142         ($len: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
143         };
144         ($len: expr, $type: expr, $field: expr, required) => {
145                 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
146                 let field_len = $field.serialized_length();
147                 BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
148                 $len.0 += field_len;
149         };
150         ($len: expr, $type: expr, $field: expr, vec_type) => {
151                 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $crate::util::ser::WithoutLength(&$field), required);
152         };
153         ($len: expr, $optional_type: expr, $optional_field: expr, option) => {
154                 if let Some(ref field) = $optional_field {
155                         BigSize($optional_type).write(&mut $len).expect("No in-memory data may fail to serialize");
156                         let field_len = field.serialized_length();
157                         BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
158                         $len.0 += field_len;
159                 }
160         };
161         ($len: expr, $type: expr, $field: expr, ignorable) => {
162                 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required);
163         };
164 }
165
166 /// See the documentation of [`write_tlv_fields`].
167 /// This is exported for use by other exported macros, do not use directly.
168 #[doc(hidden)]
169 #[macro_export]
170 macro_rules! _encode_varint_length_prefixed_tlv {
171         ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),*}) => { {
172                 use $crate::util::ser::BigSize;
173                 let len = {
174                         #[allow(unused_mut)]
175                         let mut len = $crate::util::ser::LengthCalculatingWriter(0);
176                         $(
177                                 $crate::_get_varint_length_prefixed_tlv_length!(len, $type, $field, $fieldty);
178                         )*
179                         len.0
180                 };
181                 BigSize(len as u64).write($stream)?;
182                 $crate::encode_tlv_stream!($stream, { $(($type, $field, $fieldty)),* });
183         } }
184 }
185
186 /// Errors if there are missing required TLV types between the last seen type and the type currently being processed.
187 /// This is exported for use by other exported macros, do not use directly.
188 #[doc(hidden)]
189 #[macro_export]
190 macro_rules! _check_decoded_tlv_order {
191         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value, $default: expr)) => {{
192                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
193                 let invalid_order = ($last_seen_type.is_none() || $last_seen_type.unwrap() < $type) && $typ.0 > $type;
194                 if invalid_order {
195                         $field = $default.into();
196                 }
197         }};
198         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {
199         };
200         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
201                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
202                 let invalid_order = ($last_seen_type.is_none() || $last_seen_type.unwrap() < $type) && $typ.0 > $type;
203                 if invalid_order {
204                         return Err(DecodeError::InvalidValue);
205                 }
206         }};
207         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, option) => {{
208                 // no-op
209         }};
210         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, vec_type) => {{
211                 // no-op
212         }};
213         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, ignorable) => {{
214                 // no-op
215         }};
216         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
217                 // no-op
218         }};
219         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (option, encoding: $encoding: tt)) => {{
220                 // no-op
221         }};
222 }
223
224 /// Errors if there are missing required TLV types after the last seen type.
225 /// This is exported for use by other exported macros, do not use directly.
226 #[doc(hidden)]
227 #[macro_export]
228 macro_rules! _check_missing_tlv {
229         ($last_seen_type: expr, $type: expr, $field: ident, (default_value, $default: expr)) => {{
230                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
231                 let missing_req_type = $last_seen_type.is_none() || $last_seen_type.unwrap() < $type;
232                 if missing_req_type {
233                         $field = $default.into();
234                 }
235         }};
236         ($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
237                 $field = $value;
238         };
239         ($last_seen_type: expr, $type: expr, $field: ident, required) => {{
240                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
241                 let missing_req_type = $last_seen_type.is_none() || $last_seen_type.unwrap() < $type;
242                 if missing_req_type {
243                         return Err(DecodeError::InvalidValue);
244                 }
245         }};
246         ($last_seen_type: expr, $type: expr, $field: ident, vec_type) => {{
247                 // no-op
248         }};
249         ($last_seen_type: expr, $type: expr, $field: ident, option) => {{
250                 // no-op
251         }};
252         ($last_seen_type: expr, $type: expr, $field: ident, ignorable) => {{
253                 // no-op
254         }};
255         ($last_seen_type: expr, $type: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
256                 // no-op
257         }};
258         ($last_seen_type: expr, $type: expr, $field: ident, (option, encoding: $encoding: tt)) => {{
259                 // no-op
260         }};
261 }
262
263 /// Implements deserialization for a single TLV record.
264 /// This is exported for use by other exported macros, do not use directly.
265 #[doc(hidden)]
266 #[macro_export]
267 macro_rules! _decode_tlv {
268         ($reader: expr, $field: ident, (default_value, $default: expr)) => {{
269                 $crate::_decode_tlv!($reader, $field, required)
270         }};
271         ($reader: expr, $field: ident, (static_value, $value: expr)) => {{
272         }};
273         ($reader: expr, $field: ident, required) => {{
274                 $field = $crate::util::ser::Readable::read(&mut $reader)?;
275         }};
276         ($reader: expr, $field: ident, vec_type) => {{
277                 let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::Readable::read(&mut $reader)?;
278                 $field = Some(f.0);
279         }};
280         ($reader: expr, $field: ident, option) => {{
281                 $field = Some($crate::util::ser::Readable::read(&mut $reader)?);
282         }};
283         ($reader: expr, $field: ident, ignorable) => {{
284                 $field = $crate::util::ser::MaybeReadable::read(&mut $reader)?;
285         }};
286         ($reader: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
287                 $field = Some($trait::read(&mut $reader $(, $read_arg)*)?);
288         }};
289         ($reader: expr, $field: ident, (option, encoding: ($fieldty: ty, $encoding: ident))) => {{
290                 $field = {
291                         let field: $encoding<$fieldty> = ser::Readable::read(&mut $reader)?;
292                         Some(field.0)
293                 };
294         }};
295         ($reader: expr, $field: ident, (option, encoding: $fieldty: ty)) => {{
296                 $crate::_decode_tlv!($reader, $field, option);
297         }};
298 }
299
300 /// Checks if `$val` matches `$type`.
301 /// This is exported for use by other exported macros, do not use directly.
302 #[doc(hidden)]
303 #[macro_export]
304 macro_rules! _decode_tlv_stream_match_check {
305         ($val: ident, $type: expr, (static_value, $value: expr)) => { false };
306         ($val: ident, $type: expr, $fieldty: tt) => { $val == $type }
307 }
308
309 /// Implements the TLVs deserialization part in a [`Readable`] implementation of a struct.
310 ///
311 /// This should be called inside a method which returns `Result<_, `[`DecodeError`]`>`, such as
312 /// [`Readable::read`]. It will either return an `Err` or ensure all `required` fields have been
313 /// read and optionally read `optional` fields.
314 ///
315 /// `$stream` must be a [`Read`] and will be fully consumed, reading until no more bytes remain
316 /// (i.e. it returns [`DecodeError::ShortRead`]).
317 ///
318 /// Fields MUST be sorted in `$type`-order.
319 ///
320 /// Note that the lightning TLV requirements require that a single type not appear more than once,
321 /// that TLVs are sorted in type-ascending order, and that any even types be understood by the
322 /// decoder.
323 ///
324 /// For example,
325 /// ```
326 /// # use lightning::decode_tlv_stream;
327 /// # fn read<R: lightning::io::Read> (stream: R) -> Result<(), lightning::ln::msgs::DecodeError> {
328 /// let mut required_value = 0u64;
329 /// let mut optional_value: Option<u64> = None;
330 /// decode_tlv_stream!(stream, {
331 ///     (0, required_value, required),
332 ///     (2, optional_value, option),
333 /// });
334 /// // At this point, `required_value` has been overwritten with the TLV with type 0.
335 /// // `optional_value` may have been overwritten, setting it to `Some` if a TLV with type 2 was
336 /// // present.
337 /// # Ok(())
338 /// # }
339 /// ```
340 ///
341 /// [`Readable`]: crate::util::ser::Readable
342 /// [`DecodeError`]: crate::ln::msgs::DecodeError
343 /// [`Readable::read`]: crate::util::ser::Readable::read
344 /// [`Read`]: crate::io::Read
345 /// [`DecodeError::ShortRead`]: crate::ln::msgs::DecodeError::ShortRead
346 #[macro_export]
347 macro_rules! decode_tlv_stream {
348         ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
349                 let rewind = |_, _| { unreachable!() };
350                 $crate::_decode_tlv_stream_range!($stream, .., rewind, {$(($type, $field, $fieldty)),*});
351         }
352 }
353
354 /// Similar to [`decode_tlv_stream`] with a custom TLV decoding capabilities.
355 ///
356 /// `$decode_custom_tlv` is a closure that may be optionally provided to handle custom message types.
357 /// If it is provided, it will be called with the custom type and the [`FixedLengthReader`] containing
358 /// the message contents. It should return `Ok(true)` if the custom message is successfully parsed,
359 /// `Ok(false)` if the message type is unknown, and `Err(`[`DecodeError`]`)` if parsing fails.
360 ///
361 /// [`FixedLengthReader`]: crate::util::ser::FixedLengthReader
362 /// [`DecodeError`]: crate::ln::msgs::DecodeError
363 macro_rules! decode_tlv_stream_with_custom_tlv_decode {
364         ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
365          $(, $decode_custom_tlv: expr)?) => { {
366                 let rewind = |_, _| { unreachable!() };
367                 _decode_tlv_stream_range!(
368                         $stream, .., rewind, {$(($type, $field, $fieldty)),*} $(, $decode_custom_tlv)?
369                 );
370         } }
371 }
372
373 #[doc(hidden)]
374 #[macro_export]
375 macro_rules! _decode_tlv_stream_range {
376         ($stream: expr, $range: expr, $rewind: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
377          $(, $decode_custom_tlv: expr)?) => { {
378                 use core::ops::RangeBounds;
379                 use $crate::ln::msgs::DecodeError;
380                 let mut last_seen_type: Option<u64> = None;
381                 let mut stream_ref = $stream;
382                 'tlv_read: loop {
383                         use $crate::util::ser;
384
385                         // First decode the type of this TLV:
386                         let typ: ser::BigSize = {
387                                 // We track whether any bytes were read during the consensus_decode call to
388                                 // determine whether we should break or return ShortRead if we get an
389                                 // UnexpectedEof. This should in every case be largely cosmetic, but its nice to
390                                 // pass the TLV test vectors exactly, which require this distinction.
391                                 let mut tracking_reader = ser::ReadTrackingReader::new(&mut stream_ref);
392                                 match <$crate::util::ser::BigSize as $crate::util::ser::Readable>::read(&mut tracking_reader) {
393                                         Err(DecodeError::ShortRead) => {
394                                                 if !tracking_reader.have_read {
395                                                         break 'tlv_read;
396                                                 } else {
397                                                         return Err(DecodeError::ShortRead);
398                                                 }
399                                         },
400                                         Err(e) => return Err(e),
401                                         Ok(t) => if $range.contains(&t.0) { t } else {
402                                                 drop(tracking_reader);
403
404                                                 // Assumes the type id is minimally encoded, which is enforced on read.
405                                                 use $crate::util::ser::Writeable;
406                                                 let bytes_read = t.serialized_length();
407                                                 $rewind(stream_ref, bytes_read);
408                                                 break 'tlv_read;
409                                         },
410                                 }
411                         };
412
413                         // Types must be unique and monotonically increasing:
414                         match last_seen_type {
415                                 Some(t) if typ.0 <= t => {
416                                         return Err(DecodeError::InvalidValue);
417                                 },
418                                 _ => {},
419                         }
420                         // As we read types, make sure we hit every required type between `last_seen_type` and `typ`:
421                         $({
422                                 $crate::_check_decoded_tlv_order!(last_seen_type, typ, $type, $field, $fieldty);
423                         })*
424                         last_seen_type = Some(typ.0);
425
426                         // Finally, read the length and value itself:
427                         let length: ser::BigSize = $crate::util::ser::Readable::read(&mut stream_ref)?;
428                         let mut s = ser::FixedLengthReader::new(&mut stream_ref, length.0);
429                         match typ.0 {
430                                 $(_t if $crate::_decode_tlv_stream_match_check!(_t, $type, $fieldty) => {
431                                         $crate::_decode_tlv!(s, $field, $fieldty);
432                                         if s.bytes_remain() {
433                                                 s.eat_remaining()?; // Return ShortRead if there's actually not enough bytes
434                                                 return Err(DecodeError::InvalidValue);
435                                         }
436                                 },)*
437                                 t => {
438                                         $(
439                                                 if $decode_custom_tlv(t, &mut s)? {
440                                                         // If a custom TLV was successfully read (i.e. decode_custom_tlv returns true),
441                                                         // continue to the next TLV read.
442                                                         s.eat_remaining()?;
443                                                         continue 'tlv_read;
444                                                 }
445                                         )?
446                                         if t % 2 == 0 {
447                                                 return Err(DecodeError::UnknownRequiredFeature);
448                                         }
449                                 }
450                         }
451                         s.eat_remaining()?;
452                 }
453                 // Make sure we got to each required type after we've read every TLV:
454                 $({
455                         $crate::_check_missing_tlv!(last_seen_type, $type, $field, $fieldty);
456                 })*
457         } }
458 }
459
460 macro_rules! impl_writeable_msg {
461         ($st:ident, {$($field:ident),* $(,)*}, {$(($type: expr, $tlvfield: ident, $fieldty: tt)),* $(,)*}) => {
462                 impl $crate::util::ser::Writeable for $st {
463                         fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
464                                 $( self.$field.write(w)?; )*
465                                 encode_tlv_stream!(w, {$(($type, self.$tlvfield, $fieldty)),*});
466                                 Ok(())
467                         }
468                 }
469                 impl $crate::util::ser::Readable for $st {
470                         fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
471                                 $(let $field = $crate::util::ser::Readable::read(r)?;)*
472                                 $(_init_tlv_field_var!($tlvfield, $fieldty);)*
473                                 decode_tlv_stream!(r, {$(($type, $tlvfield, $fieldty)),*});
474                                 Ok(Self {
475                                         $($field),*,
476                                         $($tlvfield),*
477                                 })
478                         }
479                 }
480         }
481 }
482
483 macro_rules! impl_writeable {
484         ($st:ident, {$($field:ident),*}) => {
485                 impl $crate::util::ser::Writeable for $st {
486                         fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
487                                 $( self.$field.write(w)?; )*
488                                 Ok(())
489                         }
490
491                         #[inline]
492                         fn serialized_length(&self) -> usize {
493                                 let mut len_calc = 0;
494                                 $( len_calc += self.$field.serialized_length(); )*
495                                 return len_calc;
496                         }
497                 }
498
499                 impl $crate::util::ser::Readable for $st {
500                         fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
501                                 Ok(Self {
502                                         $($field: $crate::util::ser::Readable::read(r)?),*
503                                 })
504                         }
505                 }
506         }
507 }
508
509 /// Write out two bytes to indicate the version of an object.
510 ///
511 /// $this_version represents a unique version of a type. Incremented whenever the type's
512 /// serialization format has changed or has a new interpretation. Used by a type's reader to
513 /// determine how to interpret fields or if it can understand a serialized object.
514 ///
515 /// $min_version_that_can_read_this is the minimum reader version which can understand this
516 /// serialized object. Previous versions will simply err with a [`DecodeError::UnknownVersion`].
517 ///
518 /// Updates to either `$this_version` or `$min_version_that_can_read_this` should be included in
519 /// release notes.
520 ///
521 /// Both version fields can be specific to this type of object.
522 ///
523 /// [`DecodeError::UnknownVersion`]: crate::ln::msgs::DecodeError::UnknownVersion
524 macro_rules! write_ver_prefix {
525         ($stream: expr, $this_version: expr, $min_version_that_can_read_this: expr) => {
526                 $stream.write_all(&[$this_version; 1])?;
527                 $stream.write_all(&[$min_version_that_can_read_this; 1])?;
528         }
529 }
530
531 /// Writes out a suffix to an object as a length-prefixed TLV stream which contains potentially
532 /// backwards-compatible, optional fields which old nodes can happily ignore.
533 ///
534 /// It is written out in TLV format and, as with all TLV fields, unknown even fields cause a
535 /// [`DecodeError::UnknownRequiredFeature`] error, with unknown odd fields ignored.
536 ///
537 /// This is the preferred method of adding new fields that old nodes can ignore and still function
538 /// correctly.
539 ///
540 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
541 #[macro_export]
542 macro_rules! write_tlv_fields {
543         ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => {
544                 $crate::_encode_varint_length_prefixed_tlv!($stream, {$(($type, $field, $fieldty)),*})
545         }
546 }
547
548 /// Reads a prefix added by [`write_ver_prefix`], above. Takes the current version of the
549 /// serialization logic for this object. This is compared against the
550 /// `$min_version_that_can_read_this` added by [`write_ver_prefix`].
551 macro_rules! read_ver_prefix {
552         ($stream: expr, $this_version: expr) => { {
553                 let ver: u8 = Readable::read($stream)?;
554                 let min_ver: u8 = Readable::read($stream)?;
555                 if min_ver > $this_version {
556                         return Err(DecodeError::UnknownVersion);
557                 }
558                 ver
559         } }
560 }
561
562 /// Reads a suffix added by [`write_tlv_fields`].
563 ///
564 /// [`write_tlv_fields`]: crate::write_tlv_fields
565 #[macro_export]
566 macro_rules! read_tlv_fields {
567         ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => { {
568                 let tlv_len: $crate::util::ser::BigSize = $crate::util::ser::Readable::read($stream)?;
569                 let mut rd = $crate::util::ser::FixedLengthReader::new($stream, tlv_len.0);
570                 $crate::decode_tlv_stream!(&mut rd, {$(($type, $field, $fieldty)),*});
571                 rd.eat_remaining().map_err(|_| $crate::ln::msgs::DecodeError::ShortRead)?;
572         } }
573 }
574
575 /// Initializes the struct fields.
576 ///
577 /// This is exported for use by other exported macros, do not use directly.
578 #[doc(hidden)]
579 #[macro_export]
580 macro_rules! _init_tlv_based_struct_field {
581         ($field: ident, (default_value, $default: expr)) => {
582                 $field.0.unwrap()
583         };
584         ($field: ident, (static_value, $value: expr)) => {
585                 $field
586         };
587         ($field: ident, option) => {
588                 $field
589         };
590         ($field: ident, ignorable) => {
591                 if $field.is_none() { return Ok(None); } else { $field.unwrap() }
592         };
593         ($field: ident, required) => {
594                 $field.0.unwrap()
595         };
596         ($field: ident, vec_type) => {
597                 $field.unwrap()
598         };
599 }
600
601 /// Initializes the variable we are going to read the TLV into.
602 ///
603 /// This is exported for use by other exported macros, do not use directly.
604 #[doc(hidden)]
605 #[macro_export]
606 macro_rules! _init_tlv_field_var {
607         ($field: ident, (default_value, $default: expr)) => {
608                 let mut $field = $crate::util::ser::OptionDeserWrapper(None);
609         };
610         ($field: ident, (static_value, $value: expr)) => {
611                 let $field;
612         };
613         ($field: ident, required) => {
614                 let mut $field = $crate::util::ser::OptionDeserWrapper(None);
615         };
616         ($field: ident, vec_type) => {
617                 let mut $field = Some(Vec::new());
618         };
619         ($field: ident, option) => {
620                 let mut $field = None;
621         };
622         ($field: ident, ignorable) => {
623                 let mut $field = None;
624         };
625 }
626
627 /// Equivalent to running [`_init_tlv_field_var`] then [`read_tlv_fields`].
628 ///
629 /// This is exported for use by other exported macros, do not use directly.
630 #[doc(hidden)]
631 #[macro_export]
632 macro_rules! _init_and_read_tlv_fields {
633         ($reader: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
634                 $(
635                         $crate::_init_tlv_field_var!($field, $fieldty);
636                 )*
637
638                 $crate::read_tlv_fields!($reader, {
639                         $(($type, $field, $fieldty)),*
640                 });
641         }
642 }
643
644 /// Implements [`Readable`]/[`Writeable`] for a struct storing it as a set of TLVs
645 /// If `$fieldty` is `required`, then `$field` is a required field that is not an Option nor a Vec.
646 /// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
647 /// If `$fieldty` is `option`, then `$field` is optional field.
648 /// If `$fieldty` is `vec_type`, then `$field` is a Vec, which needs to have its individual elements serialized.
649 ///
650 /// For example,
651 /// ```
652 /// # use lightning::impl_writeable_tlv_based;
653 /// struct LightningMessage {
654 ///     tlv_integer: u32,
655 ///     tlv_default_integer: u32,
656 ///     tlv_optional_integer: Option<u32>,
657 ///     tlv_vec_type_integer: Vec<u32>,
658 /// }
659 ///
660 /// impl_writeable_tlv_based!(LightningMessage, {
661 ///     (0, tlv_integer, required),
662 ///     (1, tlv_default_integer, (default_value, 7)),
663 ///     (2, tlv_optional_integer, option),
664 ///     (3, tlv_vec_type_integer, vec_type),
665 /// });
666 /// ```
667 ///
668 /// [`Readable`]: crate::util::ser::Readable
669 /// [`Writeable`]: crate::util::ser::Writeable
670 #[macro_export]
671 macro_rules! impl_writeable_tlv_based {
672         ($st: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
673                 impl $crate::util::ser::Writeable for $st {
674                         fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
675                                 $crate::write_tlv_fields!(writer, {
676                                         $(($type, self.$field, $fieldty)),*
677                                 });
678                                 Ok(())
679                         }
680
681                         #[inline]
682                         fn serialized_length(&self) -> usize {
683                                 use $crate::util::ser::BigSize;
684                                 let len = {
685                                         #[allow(unused_mut)]
686                                         let mut len = $crate::util::ser::LengthCalculatingWriter(0);
687                                         $(
688                                                 $crate::_get_varint_length_prefixed_tlv_length!(len, $type, self.$field, $fieldty);
689                                         )*
690                                         len.0
691                                 };
692                                 let mut len_calc = $crate::util::ser::LengthCalculatingWriter(0);
693                                 BigSize(len as u64).write(&mut len_calc).expect("No in-memory data may fail to serialize");
694                                 len + len_calc.0
695                         }
696                 }
697
698                 impl $crate::util::ser::Readable for $st {
699                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
700                                 $crate::_init_and_read_tlv_fields!(reader, {
701                                         $(($type, $field, $fieldty)),*
702                                 });
703                                 Ok(Self {
704                                         $(
705                                                 $field: $crate::_init_tlv_based_struct_field!($field, $fieldty)
706                                         ),*
707                                 })
708                         }
709                 }
710         }
711 }
712
713 /// Defines a struct for a TLV stream and a similar struct using references for non-primitive types,
714 /// implementing [`Readable`] for the former and [`Writeable`] for the latter. Useful as an
715 /// intermediary format when reading or writing a type encoded as a TLV stream. Note that each field
716 /// representing a TLV record has its type wrapped with an [`Option`]. A tuple consisting of a type
717 /// and a serialization wrapper may be given in place of a type when custom serialization is
718 /// required.
719 ///
720 /// [`Readable`]: crate::util::ser::Readable
721 /// [`Writeable`]: crate::util::ser::Writeable
722 macro_rules! tlv_stream {
723         ($name:ident, $nameref:ident, $range:expr, {
724                 $(($type:expr, $field:ident : $fieldty:tt)),* $(,)*
725         }) => {
726                 #[derive(Debug)]
727                 pub(super) struct $name {
728                         $(
729                                 pub(super) $field: Option<tlv_record_type!($fieldty)>,
730                         )*
731                 }
732
733                 #[derive(Debug, PartialEq)]
734                 pub(super) struct $nameref<'a> {
735                         $(
736                                 pub(super) $field: Option<tlv_record_ref_type!($fieldty)>,
737                         )*
738                 }
739
740                 impl<'a> $crate::util::ser::Writeable for $nameref<'a> {
741                         fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
742                                 encode_tlv_stream!(writer, {
743                                         $(($type, self.$field, (option, encoding: $fieldty))),*
744                                 });
745                                 Ok(())
746                         }
747                 }
748
749                 impl $crate::util::ser::SeekReadable for $name {
750                         fn read<R: $crate::io::Read + $crate::io::Seek>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
751                                 $(
752                                         _init_tlv_field_var!($field, option);
753                                 )*
754                                 let rewind = |cursor: &mut R, offset: usize| {
755                                         cursor.seek($crate::io::SeekFrom::Current(-(offset as i64))).expect("");
756                                 };
757                                 _decode_tlv_stream_range!(reader, $range, rewind, {
758                                         $(($type, $field, (option, encoding: $fieldty))),*
759                                 });
760
761                                 Ok(Self {
762                                         $(
763                                                 $field: $field
764                                         ),*
765                                 })
766                         }
767                 }
768         }
769 }
770
771 macro_rules! tlv_record_type {
772         (($type:ty, $wrapper:ident)) => { $type };
773         ($type:ty) => { $type };
774 }
775
776 macro_rules! tlv_record_ref_type {
777         (char) => { char };
778         (u8) => { u8 };
779         ((u16, $wrapper: ident)) => { u16 };
780         ((u32, $wrapper: ident)) => { u32 };
781         ((u64, $wrapper: ident)) => { u64 };
782         (($type:ty, $wrapper:ident)) => { &'a $type };
783         ($type:ty) => { &'a $type };
784 }
785
786 macro_rules! _impl_writeable_tlv_based_enum_common {
787         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
788                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
789         ),* $(,)*;
790         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*) => {
791                 impl $crate::util::ser::Writeable for $st {
792                         fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
793                                 match self {
794                                         $($st::$variant_name { $(ref $field),* } => {
795                                                 let id: u8 = $variant_id;
796                                                 id.write(writer)?;
797                                                 write_tlv_fields!(writer, {
798                                                         $(($type, *$field, $fieldty)),*
799                                                 });
800                                         }),*
801                                         $($st::$tuple_variant_name (ref field) => {
802                                                 let id: u8 = $tuple_variant_id;
803                                                 id.write(writer)?;
804                                                 field.write(writer)?;
805                                         }),*
806                                 }
807                                 Ok(())
808                         }
809                 }
810         }
811 }
812
813 /// Implement [`Readable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and tuple
814 /// variants stored directly.
815 /// The format is, for example
816 /// ```ignore
817 /// impl_writeable_tlv_based_enum!(EnumName,
818 ///   (0, StructVariantA) => {(0, required_variant_field, required), (1, optional_variant_field, option)},
819 ///   (1, StructVariantB) => {(0, variant_field_a, required), (1, variant_field_b, required), (2, variant_vec_field, vec_type)};
820 ///   (2, TupleVariantA), (3, TupleVariantB),
821 /// );
822 /// ```
823 /// The type is written as a single byte, followed by any variant data.
824 /// Attempts to read an unknown type byte result in [`DecodeError::UnknownRequiredFeature`].
825 ///
826 /// [`Readable`]: crate::util::ser::Readable
827 /// [`Writeable`]: crate::util::ser::Writeable
828 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
829 #[macro_export]
830 macro_rules! impl_writeable_tlv_based_enum {
831         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
832                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
833         ),* $(,)*;
834         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*) => {
835                 _impl_writeable_tlv_based_enum_common!($st,
836                         $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
837                         $(($tuple_variant_id, $tuple_variant_name)),*);
838
839                 impl $crate::util::ser::Readable for $st {
840                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
841                                 let id: u8 = $crate::util::ser::Readable::read(reader)?;
842                                 match id {
843                                         $($variant_id => {
844                                                 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
845                                                 // in the same function body. Instead, we define a closure and call it.
846                                                 let f = || {
847                                                         _init_and_read_tlv_fields!(reader, {
848                                                                 $(($type, $field, $fieldty)),*
849                                                         });
850                                                         Ok($st::$variant_name {
851                                                                 $(
852                                                                         $field: _init_tlv_based_struct_field!($field, $fieldty)
853                                                                 ),*
854                                                         })
855                                                 };
856                                                 f()
857                                         }),*
858                                         $($tuple_variant_id => {
859                                                 Ok($st::$tuple_variant_name(Readable::read(reader)?))
860                                         }),*
861                                         _ => {
862                                                 Err($crate::ln::msgs::DecodeError::UnknownRequiredFeature)
863                                         },
864                                 }
865                         }
866                 }
867         }
868 }
869
870 /// Implement [`MaybeReadable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and
871 /// tuple variants stored directly.
872 ///
873 /// This is largely identical to [`impl_writeable_tlv_based_enum`], except that odd variants will
874 /// return `Ok(None)` instead of `Err(`[`DecodeError::UnknownRequiredFeature`]`)`. It should generally be preferred
875 /// when [`MaybeReadable`] is practical instead of just [`Readable`] as it provides an upgrade path for
876 /// new variants to be added which are simply ignored by existing clients.
877 ///
878 /// [`MaybeReadable`]: crate::util::ser::MaybeReadable
879 /// [`Writeable`]: crate::util::ser::Writeable
880 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
881 /// [`Readable`]: crate::util::ser::Readable
882 #[macro_export]
883 macro_rules! impl_writeable_tlv_based_enum_upgradable {
884         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
885                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
886         ),* $(,)*
887         $(;
888         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*)*) => {
889                 _impl_writeable_tlv_based_enum_common!($st,
890                         $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
891                         $($(($tuple_variant_id, $tuple_variant_name)),*)*);
892
893                 impl $crate::util::ser::MaybeReadable for $st {
894                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Option<Self>, $crate::ln::msgs::DecodeError> {
895                                 let id: u8 = $crate::util::ser::Readable::read(reader)?;
896                                 match id {
897                                         $($variant_id => {
898                                                 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
899                                                 // in the same function body. Instead, we define a closure and call it.
900                                                 let f = || {
901                                                         _init_and_read_tlv_fields!(reader, {
902                                                                 $(($type, $field, $fieldty)),*
903                                                         });
904                                                         Ok(Some($st::$variant_name {
905                                                                 $(
906                                                                         $field: _init_tlv_based_struct_field!($field, $fieldty)
907                                                                 ),*
908                                                         }))
909                                                 };
910                                                 f()
911                                         }),*
912                                         $($($tuple_variant_id => {
913                                                 Ok(Some($st::$tuple_variant_name(Readable::read(reader)?)))
914                                         }),*)*
915                                         _ if id % 2 == 1 => Ok(None),
916                                         _ => Err(DecodeError::UnknownRequiredFeature),
917                                 }
918                         }
919                 }
920         }
921 }
922
923 #[cfg(test)]
924 mod tests {
925         use crate::io::{self, Cursor};
926         use crate::prelude::*;
927         use crate::ln::msgs::DecodeError;
928         use crate::util::ser::{Writeable, HighZeroBytesDroppedBigSize, VecWriter};
929         use bitcoin::secp256k1::PublicKey;
930
931         // The BOLT TLV test cases don't include any tests which use our "required-value" logic since
932         // the encoding layer in the BOLTs has no such concept, though it makes our macros easier to
933         // work with so they're baked into the decoder. Thus, we have a few additional tests below
934         fn tlv_reader(s: &[u8]) -> Result<(u64, u32, Option<u32>), DecodeError> {
935                 let mut s = Cursor::new(s);
936                 let mut a: u64 = 0;
937                 let mut b: u32 = 0;
938                 let mut c: Option<u32> = None;
939                 decode_tlv_stream!(&mut s, {(2, a, required), (3, b, required), (4, c, option)});
940                 Ok((a, b, c))
941         }
942
943         #[test]
944         fn tlv_v_short_read() {
945                 // We only expect a u32 for type 3 (which we are given), but the L says its 8 bytes.
946                 if let Err(DecodeError::ShortRead) = tlv_reader(&::hex::decode(
947                                 concat!("0100", "0208deadbeef1badbeef", "0308deadbeef")
948                                 ).unwrap()[..]) {
949                 } else { panic!(); }
950         }
951
952         #[test]
953         fn tlv_types_out_of_order() {
954                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
955                                 concat!("0100", "0304deadbeef", "0208deadbeef1badbeef")
956                                 ).unwrap()[..]) {
957                 } else { panic!(); }
958                 // ...even if its some field we don't understand
959                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
960                                 concat!("0208deadbeef1badbeef", "0100", "0304deadbeef")
961                                 ).unwrap()[..]) {
962                 } else { panic!(); }
963         }
964
965         #[test]
966         fn tlv_req_type_missing_or_extra() {
967                 // It's also bad if they included even fields we don't understand
968                 if let Err(DecodeError::UnknownRequiredFeature) = tlv_reader(&::hex::decode(
969                                 concat!("0100", "0208deadbeef1badbeef", "0304deadbeef", "0600")
970                                 ).unwrap()[..]) {
971                 } else { panic!(); }
972                 // ... or if they're missing fields we need
973                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
974                                 concat!("0100", "0208deadbeef1badbeef")
975                                 ).unwrap()[..]) {
976                 } else { panic!(); }
977                 // ... even if that field is even
978                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
979                                 concat!("0304deadbeef", "0500")
980                                 ).unwrap()[..]) {
981                 } else { panic!(); }
982         }
983
984         #[test]
985         fn tlv_simple_good_cases() {
986                 assert_eq!(tlv_reader(&::hex::decode(
987                                 concat!("0208deadbeef1badbeef", "03041bad1dea")
988                                 ).unwrap()[..]).unwrap(),
989                         (0xdeadbeef1badbeef, 0x1bad1dea, None));
990                 assert_eq!(tlv_reader(&::hex::decode(
991                                 concat!("0208deadbeef1badbeef", "03041bad1dea", "040401020304")
992                                 ).unwrap()[..]).unwrap(),
993                         (0xdeadbeef1badbeef, 0x1bad1dea, Some(0x01020304)));
994         }
995
996         // BOLT TLV test cases
997         fn tlv_reader_n1(s: &[u8]) -> Result<(Option<HighZeroBytesDroppedBigSize<u64>>, Option<u64>, Option<(PublicKey, u64, u64)>, Option<u16>), DecodeError> {
998                 let mut s = Cursor::new(s);
999                 let mut tlv1: Option<HighZeroBytesDroppedBigSize<u64>> = None;
1000                 let mut tlv2: Option<u64> = None;
1001                 let mut tlv3: Option<(PublicKey, u64, u64)> = None;
1002                 let mut tlv4: Option<u16> = None;
1003                 decode_tlv_stream!(&mut s, {(1, tlv1, option), (2, tlv2, option), (3, tlv3, option), (254, tlv4, option)});
1004                 Ok((tlv1, tlv2, tlv3, tlv4))
1005         }
1006
1007         #[test]
1008         fn bolt_tlv_bogus_stream() {
1009                 macro_rules! do_test {
1010                         ($stream: expr, $reason: ident) => {
1011                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1012                                 } else { panic!(); }
1013                         }
1014                 }
1015
1016                 // TLVs from the BOLT test cases which should not decode as either n1 or n2
1017                 do_test!(concat!("fd01"), ShortRead);
1018                 do_test!(concat!("fd0001", "00"), InvalidValue);
1019                 do_test!(concat!("fd0101"), ShortRead);
1020                 do_test!(concat!("0f", "fd"), ShortRead);
1021                 do_test!(concat!("0f", "fd26"), ShortRead);
1022                 do_test!(concat!("0f", "fd2602"), ShortRead);
1023                 do_test!(concat!("0f", "fd0001", "00"), InvalidValue);
1024                 do_test!(concat!("0f", "fd0201", "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), ShortRead);
1025
1026                 do_test!(concat!("12", "00"), UnknownRequiredFeature);
1027                 do_test!(concat!("fd0102", "00"), UnknownRequiredFeature);
1028                 do_test!(concat!("fe01000002", "00"), UnknownRequiredFeature);
1029                 do_test!(concat!("ff0100000000000002", "00"), UnknownRequiredFeature);
1030         }
1031
1032         #[test]
1033         fn bolt_tlv_bogus_n1_stream() {
1034                 macro_rules! do_test {
1035                         ($stream: expr, $reason: ident) => {
1036                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1037                                 } else { panic!(); }
1038                         }
1039                 }
1040
1041                 // TLVs from the BOLT test cases which should not decode as n1
1042                 do_test!(concat!("01", "09", "ffffffffffffffffff"), InvalidValue);
1043                 do_test!(concat!("01", "01", "00"), InvalidValue);
1044                 do_test!(concat!("01", "02", "0001"), InvalidValue);
1045                 do_test!(concat!("01", "03", "000100"), InvalidValue);
1046                 do_test!(concat!("01", "04", "00010000"), InvalidValue);
1047                 do_test!(concat!("01", "05", "0001000000"), InvalidValue);
1048                 do_test!(concat!("01", "06", "000100000000"), InvalidValue);
1049                 do_test!(concat!("01", "07", "00010000000000"), InvalidValue);
1050                 do_test!(concat!("01", "08", "0001000000000000"), InvalidValue);
1051                 do_test!(concat!("02", "07", "01010101010101"), ShortRead);
1052                 do_test!(concat!("02", "09", "010101010101010101"), InvalidValue);
1053                 do_test!(concat!("03", "21", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb"), ShortRead);
1054                 do_test!(concat!("03", "29", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001"), ShortRead);
1055                 do_test!(concat!("03", "30", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb000000000000000100000000000001"), ShortRead);
1056                 do_test!(concat!("03", "31", "043da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"), InvalidValue);
1057                 do_test!(concat!("03", "32", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001000000000000000001"), InvalidValue);
1058                 do_test!(concat!("fd00fe", "00"), ShortRead);
1059                 do_test!(concat!("fd00fe", "01", "01"), ShortRead);
1060                 do_test!(concat!("fd00fe", "03", "010101"), InvalidValue);
1061                 do_test!(concat!("00", "00"), UnknownRequiredFeature);
1062
1063                 do_test!(concat!("02", "08", "0000000000000226", "01", "01", "2a"), InvalidValue);
1064                 do_test!(concat!("02", "08", "0000000000000231", "02", "08", "0000000000000451"), InvalidValue);
1065                 do_test!(concat!("1f", "00", "0f", "01", "2a"), InvalidValue);
1066                 do_test!(concat!("1f", "00", "1f", "01", "2a"), InvalidValue);
1067
1068                 // The last BOLT test modified to not require creating a new decoder for one trivial test.
1069                 do_test!(concat!("ffffffffffffffffff", "00", "01", "00"), InvalidValue);
1070         }
1071
1072         #[test]
1073         fn bolt_tlv_valid_n1_stream() {
1074                 macro_rules! do_test {
1075                         ($stream: expr, $tlv1: expr, $tlv2: expr, $tlv3: expr, $tlv4: expr) => {
1076                                 if let Ok((tlv1, tlv2, tlv3, tlv4)) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1077                                         assert_eq!(tlv1.map(|v| v.0), $tlv1);
1078                                         assert_eq!(tlv2, $tlv2);
1079                                         assert_eq!(tlv3, $tlv3);
1080                                         assert_eq!(tlv4, $tlv4);
1081                                 } else { panic!(); }
1082                         }
1083                 }
1084
1085                 do_test!(concat!(""), None, None, None, None);
1086                 do_test!(concat!("21", "00"), None, None, None, None);
1087                 do_test!(concat!("fd0201", "00"), None, None, None, None);
1088                 do_test!(concat!("fd00fd", "00"), None, None, None, None);
1089                 do_test!(concat!("fd00ff", "00"), None, None, None, None);
1090                 do_test!(concat!("fe02000001", "00"), None, None, None, None);
1091                 do_test!(concat!("ff0200000000000001", "00"), None, None, None, None);
1092
1093                 do_test!(concat!("01", "00"), Some(0), None, None, None);
1094                 do_test!(concat!("01", "01", "01"), Some(1), None, None, None);
1095                 do_test!(concat!("01", "02", "0100"), Some(256), None, None, None);
1096                 do_test!(concat!("01", "03", "010000"), Some(65536), None, None, None);
1097                 do_test!(concat!("01", "04", "01000000"), Some(16777216), None, None, None);
1098                 do_test!(concat!("01", "05", "0100000000"), Some(4294967296), None, None, None);
1099                 do_test!(concat!("01", "06", "010000000000"), Some(1099511627776), None, None, None);
1100                 do_test!(concat!("01", "07", "01000000000000"), Some(281474976710656), None, None, None);
1101                 do_test!(concat!("01", "08", "0100000000000000"), Some(72057594037927936), None, None, None);
1102                 do_test!(concat!("02", "08", "0000000000000226"), None, Some((0 << 30) | (0 << 5) | (550 << 0)), None, None);
1103                 do_test!(concat!("03", "31", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"),
1104                         None, None, Some((
1105                                 PublicKey::from_slice(&::hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]).unwrap(), 1, 2)),
1106                         None);
1107                 do_test!(concat!("fd00fe", "02", "0226"), None, None, None, Some(550));
1108         }
1109
1110         fn do_simple_test_tlv_write() -> Result<(), io::Error> {
1111                 let mut stream = VecWriter(Vec::new());
1112
1113                 stream.0.clear();
1114                 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, 1u8, required), (42, None::<u64>, option)});
1115                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1116
1117                 stream.0.clear();
1118                 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, Some(1u8), option)});
1119                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1120
1121                 stream.0.clear();
1122                 _encode_varint_length_prefixed_tlv!(&mut stream, {(4, 0xabcdu16, required), (42, None::<u64>, option)});
1123                 assert_eq!(stream.0, ::hex::decode("040402abcd").unwrap());
1124
1125                 stream.0.clear();
1126                 _encode_varint_length_prefixed_tlv!(&mut stream, {(42, None::<u64>, option), (0xff, 0xabcdu16, required)});
1127                 assert_eq!(stream.0, ::hex::decode("06fd00ff02abcd").unwrap());
1128
1129                 stream.0.clear();
1130                 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, 1u64, required), (42, None::<u64>, option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1131                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1132
1133                 stream.0.clear();
1134                 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, Some(1u64), option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1135                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1136
1137                 Ok(())
1138         }
1139
1140         #[test]
1141         fn simple_test_tlv_write() {
1142                 do_simple_test_tlv_write().unwrap();
1143         }
1144 }