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