1 // This file is Copyright its original authors, visible in version control
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
10 //! Some macros that implement [`Readable`]/[`Writeable`] traits for lightning messages.
11 //! They also handle serialization and deserialization of TLVs.
13 //! [`Readable`]: crate::util::ser::Readable
14 //! [`Writeable`]: crate::util::ser::Writeable
16 /// Implements serialization for a single TLV record.
17 /// This is exported for use by other exported macros, do not use directly.
20 macro_rules! _encode_tlv {
21 ($stream: expr, $type: expr, $field: expr, (default_value, $default: expr)) => {
22 $crate::_encode_tlv!($stream, $type, $field, required)
24 ($stream: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
25 let _ = &$field; // Ensure we "use" the $field
27 ($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)?;
32 ($stream: expr, $type: expr, $field: expr, vec_type) => {
33 $crate::_encode_tlv!($stream, $type, $crate::util::ser::WithoutLength(&$field), required);
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($stream)?;
42 ($stream: expr, $type: expr, $field: expr, (option, encoding: ($fieldty: ty, $encoding: ident))) => {
43 $crate::_encode_tlv!($stream, $type, $field.map(|f| $encoding(f)), option);
45 ($stream: expr, $type: expr, $field: expr, (option, encoding: $fieldty: ty)) => {
46 $crate::_encode_tlv!($stream, $type, $field, option);
50 /// Panics if the last seen TLV type is not numerically less than the TLV type currently being checked.
51 /// This is exported for use by other exported macros, do not use directly.
54 macro_rules! _check_encoded_tlv_order {
55 ($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 debug_assert!(t <= $type);
60 $last_type = Some($type);
64 /// Implements the TLVs serialization part in a [`Writeable`] implementation of a struct.
66 /// This should be called inside a method which returns `Result<_, `[`io::Error`]`>`, such as
67 /// [`Writeable::write`]. It will only return an `Err` if the stream `Err`s or [`Writeable::write`]
68 /// on one of the fields `Err`s.
70 /// `$stream` must be a `&mut `[`Writer`] which will receive the bytes for each TLV in the stream.
72 /// Fields MUST be sorted in `$type`-order.
74 /// Note that the lightning TLV requirements require that a single type not appear more than once,
75 /// that TLVs are sorted in type-ascending order, and that any even types be understood by the
78 /// Any `option` fields which have a value of `None` will not be serialized at all.
82 /// # use lightning::encode_tlv_stream;
83 /// # fn write<W: lightning::util::ser::Writer> (stream: &mut W) -> Result<(), lightning::io::Error> {
84 /// let mut required_value = 0u64;
85 /// let mut optional_value: Option<u64> = None;
86 /// encode_tlv_stream!(stream, {
87 /// (0, required_value, required),
88 /// (1, Some(42u64), option),
89 /// (2, optional_value, option),
91 /// // At this point `required_value` has been written as a TLV of type 0, `42u64` has been written
92 /// // as a TLV of type 1 (indicating the reader may ignore it if it is not understood), and *no*
93 /// // TLV is written with type 2.
98 /// [`Writeable`]: crate::util::ser::Writeable
99 /// [`io::Error`]: crate::io::Error
100 /// [`Writeable::write`]: crate::util::ser::Writeable::write
101 /// [`Writer`]: crate::util::ser::Writer
103 macro_rules! encode_tlv_stream {
104 ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => { {
105 #[allow(unused_imports)]
107 ln::msgs::DecodeError,
110 util::ser::Writeable,
114 $crate::_encode_tlv!($stream, $type, $field, $fieldty);
117 #[allow(unused_mut, unused_variables, unused_assignments)]
118 #[cfg(debug_assertions)]
120 let mut last_seen: Option<u64> = None;
122 $crate::_check_encoded_tlv_order!(last_seen, $type, $fieldty);
128 /// Adds the length of the serialized field to a [`LengthCalculatingWriter`].
129 /// This is exported for use by other exported macros, do not use directly.
131 /// [`LengthCalculatingWriter`]: crate::util::ser::LengthCalculatingWriter
134 macro_rules! _get_varint_length_prefixed_tlv_length {
135 ($len: expr, $type: expr, $field: expr, (default_value, $default: expr)) => {
136 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
138 ($len: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
140 ($len: expr, $type: expr, $field: expr, required) => {
141 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
142 let field_len = $field.serialized_length();
143 BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
146 ($len: expr, $type: expr, $field: expr, vec_type) => {
147 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $crate::util::ser::WithoutLength(&$field), required);
149 ($len: expr, $optional_type: expr, $optional_field: expr, option) => {
150 if let Some(ref field) = $optional_field {
151 BigSize($optional_type).write(&mut $len).expect("No in-memory data may fail to serialize");
152 let field_len = field.serialized_length();
153 BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
159 /// See the documentation of [`write_tlv_fields`].
160 /// This is exported for use by other exported macros, do not use directly.
163 macro_rules! _encode_varint_length_prefixed_tlv {
164 ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),*}) => { {
165 use $crate::util::ser::BigSize;
168 let mut len = $crate::util::ser::LengthCalculatingWriter(0);
170 $crate::_get_varint_length_prefixed_tlv_length!(len, $type, $field, $fieldty);
174 BigSize(len as u64).write($stream)?;
175 $crate::encode_tlv_stream!($stream, { $(($type, $field, $fieldty)),* });
179 /// Errors if there are missing required TLV types between the last seen type and the type currently being processed.
180 /// This is exported for use by other exported macros, do not use directly.
183 macro_rules! _check_decoded_tlv_order {
184 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value, $default: expr)) => {{
185 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
186 let invalid_order = ($last_seen_type.is_none() || $last_seen_type.unwrap() < $type) && $typ.0 > $type;
188 $field = $default.into();
191 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {
193 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
194 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
195 let invalid_order = ($last_seen_type.is_none() || $last_seen_type.unwrap() < $type) && $typ.0 > $type;
197 return Err(DecodeError::InvalidValue);
200 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, option) => {{
203 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, vec_type) => {{
206 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, ignorable) => {{
209 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
212 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (option, encoding: $encoding: tt)) => {{
217 /// Errors if there are missing required TLV types after the last seen type.
218 /// This is exported for use by other exported macros, do not use directly.
221 macro_rules! _check_missing_tlv {
222 ($last_seen_type: expr, $type: expr, $field: ident, (default_value, $default: expr)) => {{
223 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
224 let missing_req_type = $last_seen_type.is_none() || $last_seen_type.unwrap() < $type;
225 if missing_req_type {
226 $field = $default.into();
229 ($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
232 ($last_seen_type: expr, $type: expr, $field: ident, required) => {{
233 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
234 let missing_req_type = $last_seen_type.is_none() || $last_seen_type.unwrap() < $type;
235 if missing_req_type {
236 return Err(DecodeError::InvalidValue);
239 ($last_seen_type: expr, $type: expr, $field: ident, vec_type) => {{
242 ($last_seen_type: expr, $type: expr, $field: ident, option) => {{
245 ($last_seen_type: expr, $type: expr, $field: ident, ignorable) => {{
248 ($last_seen_type: expr, $type: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
251 ($last_seen_type: expr, $type: expr, $field: ident, (option, encoding: $encoding: tt)) => {{
256 /// Implements deserialization for a single TLV record.
257 /// This is exported for use by other exported macros, do not use directly.
260 macro_rules! _decode_tlv {
261 ($reader: expr, $field: ident, (default_value, $default: expr)) => {{
262 $crate::_decode_tlv!($reader, $field, required)
264 ($reader: expr, $field: ident, (static_value, $value: expr)) => {{
266 ($reader: expr, $field: ident, required) => {{
267 $field = $crate::util::ser::Readable::read(&mut $reader)?;
269 ($reader: expr, $field: ident, vec_type) => {{
270 let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::Readable::read(&mut $reader)?;
273 ($reader: expr, $field: ident, option) => {{
274 $field = Some($crate::util::ser::Readable::read(&mut $reader)?);
276 ($reader: expr, $field: ident, ignorable) => {{
277 $field = $crate::util::ser::MaybeReadable::read(&mut $reader)?;
279 ($reader: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
280 $field = Some($trait::read(&mut $reader $(, $read_arg)*)?);
282 ($reader: expr, $field: ident, (option, encoding: ($fieldty: ty, $encoding: ident))) => {{
284 let field: $encoding<$fieldty> = ser::Readable::read(&mut $reader)?;
288 ($reader: expr, $field: ident, (option, encoding: $fieldty: ty)) => {{
289 $crate::_decode_tlv!($reader, $field, option);
293 /// Checks if `$val` matches `$type`.
294 /// This is exported for use by other exported macros, do not use directly.
297 macro_rules! _decode_tlv_stream_match_check {
298 ($val: ident, $type: expr, (static_value, $value: expr)) => { false };
299 ($val: ident, $type: expr, $fieldty: tt) => { $val == $type }
302 /// Implements the TLVs deserialization part in a [`Readable`] implementation of a struct.
304 /// This should be called inside a method which returns `Result<_, `[`DecodeError`]`>`, such as
305 /// [`Readable::read`]. It will either return an `Err` or ensure all `required` fields have been
306 /// read and optionally read `optional` fields.
308 /// `$stream` must be a [`Read`] and will be fully consumed, reading until no more bytes remain
309 /// (i.e. it returns [`DecodeError::ShortRead`]).
311 /// Fields MUST be sorted in `$type`-order.
313 /// Note that the lightning TLV requirements require that a single type not appear more than once,
314 /// that TLVs are sorted in type-ascending order, and that any even types be understood by the
319 /// # use lightning::decode_tlv_stream;
320 /// # fn read<R: lightning::io::Read> (stream: R) -> Result<(), lightning::ln::msgs::DecodeError> {
321 /// let mut required_value = 0u64;
322 /// let mut optional_value: Option<u64> = None;
323 /// decode_tlv_stream!(stream, {
324 /// (0, required_value, required),
325 /// (2, optional_value, option),
327 /// // At this point, `required_value` has been overwritten with the TLV with type 0.
328 /// // `optional_value` may have been overwritten, setting it to `Some` if a TLV with type 2 was
334 /// [`Readable`]: crate::util::ser::Readable
335 /// [`DecodeError`]: crate::ln::msgs::DecodeError
336 /// [`Readable::read`]: crate::util::ser::Readable::read
337 /// [`Read`]: crate::io::Read
338 /// [`DecodeError::ShortRead`]: crate::ln::msgs::DecodeError::ShortRead
340 macro_rules! decode_tlv_stream {
341 ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
342 let rewind = |_, _| { unreachable!() };
343 $crate::_decode_tlv_stream_range!($stream, .., rewind, {$(($type, $field, $fieldty)),*});
347 /// Similar to [`decode_tlv_stream`] with a custom TLV decoding capabilities.
349 /// `$decode_custom_tlv` is a closure that may be optionally provided to handle custom message types.
350 /// If it is provided, it will be called with the custom type and the [`FixedLengthReader`] containing
351 /// the message contents. It should return `Ok(true)` if the custom message is successfully parsed,
352 /// `Ok(false)` if the message type is unknown, and `Err(`[`DecodeError`]`)` if parsing fails.
354 /// [`FixedLengthReader`]: crate::util::ser::FixedLengthReader
355 /// [`DecodeError`]: crate::ln::msgs::DecodeError
356 macro_rules! decode_tlv_stream_with_custom_tlv_decode {
357 ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
358 $(, $decode_custom_tlv: expr)?) => { {
359 let rewind = |_, _| { unreachable!() };
360 _decode_tlv_stream_range!(
361 $stream, .., rewind, {$(($type, $field, $fieldty)),*} $(, $decode_custom_tlv)?
368 macro_rules! _decode_tlv_stream_range {
369 ($stream: expr, $range: expr, $rewind: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
370 $(, $decode_custom_tlv: expr)?) => { {
371 use core::ops::RangeBounds;
372 use $crate::ln::msgs::DecodeError;
373 let mut last_seen_type: Option<u64> = None;
374 let mut stream_ref = $stream;
376 use $crate::util::ser;
378 // First decode the type of this TLV:
379 let typ: ser::BigSize = {
380 // We track whether any bytes were read during the consensus_decode call to
381 // determine whether we should break or return ShortRead if we get an
382 // UnexpectedEof. This should in every case be largely cosmetic, but its nice to
383 // pass the TLV test vectors exactly, which require this distinction.
384 let mut tracking_reader = ser::ReadTrackingReader::new(&mut stream_ref);
385 match <$crate::util::ser::BigSize as $crate::util::ser::Readable>::read(&mut tracking_reader) {
386 Err(DecodeError::ShortRead) => {
387 if !tracking_reader.have_read {
390 return Err(DecodeError::ShortRead);
393 Err(e) => return Err(e),
394 Ok(t) => if $range.contains(&t.0) { t } else {
395 drop(tracking_reader);
397 // Assumes the type id is minimally encoded, which is enforced on read.
398 use $crate::util::ser::Writeable;
399 let bytes_read = t.serialized_length();
400 $rewind(stream_ref, bytes_read);
406 // Types must be unique and monotonically increasing:
407 match last_seen_type {
408 Some(t) if typ.0 <= t => {
409 return Err(DecodeError::InvalidValue);
413 // As we read types, make sure we hit every required type between `last_seen_type` and `typ`:
415 $crate::_check_decoded_tlv_order!(last_seen_type, typ, $type, $field, $fieldty);
417 last_seen_type = Some(typ.0);
419 // Finally, read the length and value itself:
420 let length: ser::BigSize = $crate::util::ser::Readable::read(&mut stream_ref)?;
421 let mut s = ser::FixedLengthReader::new(&mut stream_ref, length.0);
423 $(_t if $crate::_decode_tlv_stream_match_check!(_t, $type, $fieldty) => {
424 $crate::_decode_tlv!(s, $field, $fieldty);
425 if s.bytes_remain() {
426 s.eat_remaining()?; // Return ShortRead if there's actually not enough bytes
427 return Err(DecodeError::InvalidValue);
432 if $decode_custom_tlv(t, &mut s)? {
433 // If a custom TLV was successfully read (i.e. decode_custom_tlv returns true),
434 // continue to the next TLV read.
440 return Err(DecodeError::UnknownRequiredFeature);
446 // Make sure we got to each required type after we've read every TLV:
448 $crate::_check_missing_tlv!(last_seen_type, $type, $field, $fieldty);
453 macro_rules! impl_writeable_msg {
454 ($st:ident, {$($field:ident),* $(,)*}, {$(($type: expr, $tlvfield: ident, $fieldty: tt)),* $(,)*}) => {
455 impl $crate::util::ser::Writeable for $st {
456 fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
457 $( self.$field.write(w)?; )*
458 encode_tlv_stream!(w, {$(($type, self.$tlvfield, $fieldty)),*});
462 impl $crate::util::ser::Readable for $st {
463 fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
464 $(let $field = $crate::util::ser::Readable::read(r)?;)*
465 $(_init_tlv_field_var!($tlvfield, $fieldty);)*
466 decode_tlv_stream!(r, {$(($type, $tlvfield, $fieldty)),*});
476 macro_rules! impl_writeable {
477 ($st:ident, {$($field:ident),*}) => {
478 impl $crate::util::ser::Writeable for $st {
479 fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
480 $( self.$field.write(w)?; )*
485 fn serialized_length(&self) -> usize {
486 let mut len_calc = 0;
487 $( len_calc += self.$field.serialized_length(); )*
492 impl $crate::util::ser::Readable for $st {
493 fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
495 $($field: $crate::util::ser::Readable::read(r)?),*
502 /// Write out two bytes to indicate the version of an object.
503 /// $this_version represents a unique version of a type. Incremented whenever the type's
504 /// serialization format has changed or has a new interpretation. Used by a type's
505 /// reader to determine how to interpret fields or if it can understand a serialized
507 /// $min_version_that_can_read_this is the minimum reader version which can understand this
508 /// serialized object. Previous versions will simply err with a
509 /// [`DecodeError::UnknownVersion`].
511 /// Updates to either `$this_version` or `$min_version_that_can_read_this` should be included in
514 /// Both version fields can be specific to this type of object.
516 /// [`DecodeError::UnknownVersion`]: crate::ln::msgs::DecodeError::UnknownVersion
517 macro_rules! write_ver_prefix {
518 ($stream: expr, $this_version: expr, $min_version_that_can_read_this: expr) => {
519 $stream.write_all(&[$this_version; 1])?;
520 $stream.write_all(&[$min_version_that_can_read_this; 1])?;
524 /// Writes out a suffix to an object as a length-prefixed TLV stream which contains potentially
525 /// backwards-compatible, optional fields which old nodes can happily ignore.
527 /// It is written out in TLV format and, as with all TLV fields, unknown even fields cause a
528 /// [`DecodeError::UnknownRequiredFeature`] error, with unknown odd fields ignored.
530 /// This is the preferred method of adding new fields that old nodes can ignore and still function
533 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
535 macro_rules! write_tlv_fields {
536 ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => {
537 $crate::_encode_varint_length_prefixed_tlv!($stream, {$(($type, $field, $fieldty)),*})
541 /// Reads a prefix added by [`write_ver_prefix`], above. Takes the current version of the
542 /// serialization logic for this object. This is compared against the
543 /// `$min_version_that_can_read_this` added by [`write_ver_prefix`].
544 macro_rules! read_ver_prefix {
545 ($stream: expr, $this_version: expr) => { {
546 let ver: u8 = Readable::read($stream)?;
547 let min_ver: u8 = Readable::read($stream)?;
548 if min_ver > $this_version {
549 return Err(DecodeError::UnknownVersion);
555 /// Reads a suffix added by [`write_tlv_fields`].
557 /// [`write_tlv_fields`]: crate::write_tlv_fields
559 macro_rules! read_tlv_fields {
560 ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => { {
561 let tlv_len: $crate::util::ser::BigSize = $crate::util::ser::Readable::read($stream)?;
562 let mut rd = $crate::util::ser::FixedLengthReader::new($stream, tlv_len.0);
563 $crate::decode_tlv_stream!(&mut rd, {$(($type, $field, $fieldty)),*});
564 rd.eat_remaining().map_err(|_| $crate::ln::msgs::DecodeError::ShortRead)?;
568 /// Initializes the struct fields.
569 /// This is exported for use by other exported macros, do not use directly.
572 macro_rules! _init_tlv_based_struct_field {
573 ($field: ident, (default_value, $default: expr)) => {
576 ($field: ident, (static_value, $value: expr)) => {
579 ($field: ident, option) => {
582 ($field: ident, required) => {
585 ($field: ident, vec_type) => {
590 /// Initializes the variable we are going to read the TLV into.
591 /// This is exported for use by other exported macros, do not use directly.
594 macro_rules! _init_tlv_field_var {
595 ($field: ident, (default_value, $default: expr)) => {
596 let mut $field = $crate::util::ser::OptionDeserWrapper(None);
598 ($field: ident, (static_value, $value: expr)) => {
601 ($field: ident, required) => {
602 let mut $field = $crate::util::ser::OptionDeserWrapper(None);
604 ($field: ident, vec_type) => {
605 let mut $field = Some(Vec::new());
607 ($field: ident, option) => {
608 let mut $field = None;
612 /// Equivalent to running [`_init_tlv_field_var`] then [`read_tlv_fields`].
613 /// This is exported for use by other exported macros, do not use directly.
616 macro_rules! _init_and_read_tlv_fields {
617 ($reader: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
619 $crate::_init_tlv_field_var!($field, $fieldty);
622 $crate::read_tlv_fields!($reader, {
623 $(($type, $field, $fieldty)),*
628 /// Implements [`Readable`]/[`Writeable`] for a struct storing it as a set of TLVs
629 /// If `$fieldty` is `required`, then `$field` is a required field that is not an Option nor a Vec.
630 /// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
631 /// If `$fieldty` is `option`, then `$field` is optional field.
632 /// If `$fieldty` is `vec_type`, then `$field` is a Vec, which needs to have its individual elements serialized.
636 /// # use lightning::impl_writeable_tlv_based;
637 /// struct LightningMessage {
638 /// tlv_integer: u32,
639 /// tlv_default_integer: u32,
640 /// tlv_optional_integer: Option<u32>,
641 /// tlv_vec_type_integer: Vec<u32>,
644 /// impl_writeable_tlv_based!(LightningMessage, {
645 /// (0, tlv_integer, required),
646 /// (1, tlv_default_integer, (default_value, 7)),
647 /// (2, tlv_optional_integer, option),
648 /// (3, tlv_vec_type_integer, vec_type),
652 /// [`Readable`]: crate::util::ser::Readable
653 /// [`Writeable`]: crate::util::ser::Writeable
655 macro_rules! impl_writeable_tlv_based {
656 ($st: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
657 impl $crate::util::ser::Writeable for $st {
658 fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
659 $crate::write_tlv_fields!(writer, {
660 $(($type, self.$field, $fieldty)),*
666 fn serialized_length(&self) -> usize {
667 use $crate::util::ser::BigSize;
670 let mut len = $crate::util::ser::LengthCalculatingWriter(0);
672 $crate::_get_varint_length_prefixed_tlv_length!(len, $type, self.$field, $fieldty);
676 let mut len_calc = $crate::util::ser::LengthCalculatingWriter(0);
677 BigSize(len as u64).write(&mut len_calc).expect("No in-memory data may fail to serialize");
682 impl $crate::util::ser::Readable for $st {
683 fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
684 $crate::_init_and_read_tlv_fields!(reader, {
685 $(($type, $field, $fieldty)),*
689 $field: $crate::_init_tlv_based_struct_field!($field, $fieldty)
697 /// Defines a struct for a TLV stream and a similar struct using references for non-primitive types,
698 /// implementing [`Readable`] for the former and [`Writeable`] for the latter. Useful as an
699 /// intermediary format when reading or writing a type encoded as a TLV stream. Note that each field
700 /// representing a TLV record has its type wrapped with an [`Option`]. A tuple consisting of a type
701 /// and a serialization wrapper may be given in place of a type when custom serialization is
704 /// [`Readable`]: crate::util::ser::Readable
705 /// [`Writeable`]: crate::util::ser::Writeable
706 macro_rules! tlv_stream {
707 ($name:ident, $nameref:ident, $range:expr, {
708 $(($type:expr, $field:ident : $fieldty:tt)),* $(,)*
711 pub(super) struct $name {
713 pub(super) $field: Option<tlv_record_type!($fieldty)>,
717 #[derive(Debug, PartialEq)]
718 pub(super) struct $nameref<'a> {
720 pub(super) $field: Option<tlv_record_ref_type!($fieldty)>,
724 impl<'a> $crate::util::ser::Writeable for $nameref<'a> {
725 fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
726 encode_tlv_stream!(writer, {
727 $(($type, self.$field, (option, encoding: $fieldty))),*
733 impl $crate::util::ser::SeekReadable for $name {
734 fn read<R: $crate::io::Read + $crate::io::Seek>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
736 _init_tlv_field_var!($field, option);
738 let rewind = |cursor: &mut R, offset: usize| {
739 cursor.seek($crate::io::SeekFrom::Current(-(offset as i64))).expect("");
741 _decode_tlv_stream_range!(reader, $range, rewind, {
742 $(($type, $field, (option, encoding: $fieldty))),*
755 macro_rules! tlv_record_type {
756 (($type:ty, $wrapper:ident)) => { $type };
757 ($type:ty) => { $type };
760 macro_rules! tlv_record_ref_type {
763 ((u16, $wrapper: ident)) => { u16 };
764 ((u32, $wrapper: ident)) => { u32 };
765 ((u64, $wrapper: ident)) => { u64 };
766 (($type:ty, $wrapper:ident)) => { &'a $type };
767 ($type:ty) => { &'a $type };
770 macro_rules! _impl_writeable_tlv_based_enum_common {
771 ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
772 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
774 $(($tuple_variant_id: expr, $tuple_variant_name: ident)),* $(,)*) => {
775 impl $crate::util::ser::Writeable for $st {
776 fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
778 $($st::$variant_name { $(ref $field),* } => {
779 let id: u8 = $variant_id;
781 write_tlv_fields!(writer, {
782 $(($type, *$field, $fieldty)),*
785 $($st::$tuple_variant_name (ref field) => {
786 let id: u8 = $tuple_variant_id;
788 field.write(writer)?;
797 /// Implement [`MaybeReadable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and
798 /// tuple variants stored directly.
800 /// This is largely identical to [`impl_writeable_tlv_based_enum`], except that odd variants will
801 /// return `Ok(None)` instead of `Err(`[`DecodeError::UnknownRequiredFeature`]`)`. It should generally be preferred
802 /// when [`MaybeReadable`] is practical instead of just [`Readable`] as it provides an upgrade path for
803 /// new variants to be added which are simply ignored by existing clients.
805 /// [`MaybeReadable`]: crate::util::ser::MaybeReadable
806 /// [`Writeable`]: crate::util::ser::Writeable
807 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
808 /// [`Readable`]: crate::util::ser::Readable
809 macro_rules! impl_writeable_tlv_based_enum_upgradable {
810 ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
811 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
814 $(($tuple_variant_id: expr, $tuple_variant_name: ident)),* $(,)*)*) => {
815 _impl_writeable_tlv_based_enum_common!($st,
816 $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
817 $($(($tuple_variant_id, $tuple_variant_name)),*)*);
819 impl $crate::util::ser::MaybeReadable for $st {
820 fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Option<Self>, $crate::ln::msgs::DecodeError> {
821 let id: u8 = $crate::util::ser::Readable::read(reader)?;
824 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
825 // in the same function body. Instead, we define a closure and call it.
827 _init_and_read_tlv_fields!(reader, {
828 $(($type, $field, $fieldty)),*
830 Ok(Some($st::$variant_name {
832 $field: _init_tlv_based_struct_field!($field, $fieldty)
838 $($($tuple_variant_id => {
839 Ok(Some($st::$tuple_variant_name(Readable::read(reader)?)))
841 _ if id % 2 == 1 => Ok(None),
842 _ => Err(DecodeError::UnknownRequiredFeature),
850 /// Implement [`Readable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and tuple
851 /// variants stored directly.
852 /// The format is, for example
853 /// impl_writeable_tlv_based_enum!(EnumName,
854 /// (0, StructVariantA) => {(0, required_variant_field, required), (1, optional_variant_field, option)},
855 /// (1, StructVariantB) => {(0, variant_field_a, required), (1, variant_field_b, required), (2, variant_vec_field, vec_type)};
856 /// (2, TupleVariantA), (3, TupleVariantB),
858 /// The type is written as a single byte, followed by any variant data.
859 /// Attempts to read an unknown type byte result in [`DecodeError::UnknownRequiredFeature`].
861 /// [`Readable`]: crate::util::ser::Readable
862 /// [`Writeable`]: crate::util::ser::Writeable
863 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
864 macro_rules! impl_writeable_tlv_based_enum {
865 ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
866 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
868 $(($tuple_variant_id: expr, $tuple_variant_name: ident)),* $(,)*) => {
869 _impl_writeable_tlv_based_enum_common!($st,
870 $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
871 $(($tuple_variant_id, $tuple_variant_name)),*);
873 impl $crate::util::ser::Readable for $st {
874 fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
875 let id: u8 = $crate::util::ser::Readable::read(reader)?;
878 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
879 // in the same function body. Instead, we define a closure and call it.
881 _init_and_read_tlv_fields!(reader, {
882 $(($type, $field, $fieldty)),*
884 Ok($st::$variant_name {
886 $field: _init_tlv_based_struct_field!($field, $fieldty)
892 $($tuple_variant_id => {
893 Ok($st::$tuple_variant_name(Readable::read(reader)?))
896 Err($crate::ln::msgs::DecodeError::UnknownRequiredFeature)
906 use crate::io::{self, Cursor};
907 use crate::prelude::*;
908 use crate::ln::msgs::DecodeError;
909 use crate::util::ser::{Writeable, HighZeroBytesDroppedBigSize, VecWriter};
910 use bitcoin::secp256k1::PublicKey;
912 // The BOLT TLV test cases don't include any tests which use our "required-value" logic since
913 // the encoding layer in the BOLTs has no such concept, though it makes our macros easier to
914 // work with so they're baked into the decoder. Thus, we have a few additional tests below
915 fn tlv_reader(s: &[u8]) -> Result<(u64, u32, Option<u32>), DecodeError> {
916 let mut s = Cursor::new(s);
919 let mut c: Option<u32> = None;
920 decode_tlv_stream!(&mut s, {(2, a, required), (3, b, required), (4, c, option)});
925 fn tlv_v_short_read() {
926 // We only expect a u32 for type 3 (which we are given), but the L says its 8 bytes.
927 if let Err(DecodeError::ShortRead) = tlv_reader(&::hex::decode(
928 concat!("0100", "0208deadbeef1badbeef", "0308deadbeef")
934 fn tlv_types_out_of_order() {
935 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
936 concat!("0100", "0304deadbeef", "0208deadbeef1badbeef")
939 // ...even if its some field we don't understand
940 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
941 concat!("0208deadbeef1badbeef", "0100", "0304deadbeef")
947 fn tlv_req_type_missing_or_extra() {
948 // It's also bad if they included even fields we don't understand
949 if let Err(DecodeError::UnknownRequiredFeature) = tlv_reader(&::hex::decode(
950 concat!("0100", "0208deadbeef1badbeef", "0304deadbeef", "0600")
953 // ... or if they're missing fields we need
954 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
955 concat!("0100", "0208deadbeef1badbeef")
958 // ... even if that field is even
959 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
960 concat!("0304deadbeef", "0500")
966 fn tlv_simple_good_cases() {
967 assert_eq!(tlv_reader(&::hex::decode(
968 concat!("0208deadbeef1badbeef", "03041bad1dea")
969 ).unwrap()[..]).unwrap(),
970 (0xdeadbeef1badbeef, 0x1bad1dea, None));
971 assert_eq!(tlv_reader(&::hex::decode(
972 concat!("0208deadbeef1badbeef", "03041bad1dea", "040401020304")
973 ).unwrap()[..]).unwrap(),
974 (0xdeadbeef1badbeef, 0x1bad1dea, Some(0x01020304)));
977 // BOLT TLV test cases
978 fn tlv_reader_n1(s: &[u8]) -> Result<(Option<HighZeroBytesDroppedBigSize<u64>>, Option<u64>, Option<(PublicKey, u64, u64)>, Option<u16>), DecodeError> {
979 let mut s = Cursor::new(s);
980 let mut tlv1: Option<HighZeroBytesDroppedBigSize<u64>> = None;
981 let mut tlv2: Option<u64> = None;
982 let mut tlv3: Option<(PublicKey, u64, u64)> = None;
983 let mut tlv4: Option<u16> = None;
984 decode_tlv_stream!(&mut s, {(1, tlv1, option), (2, tlv2, option), (3, tlv3, option), (254, tlv4, option)});
985 Ok((tlv1, tlv2, tlv3, tlv4))
989 fn bolt_tlv_bogus_stream() {
990 macro_rules! do_test {
991 ($stream: expr, $reason: ident) => {
992 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
997 // TLVs from the BOLT test cases which should not decode as either n1 or n2
998 do_test!(concat!("fd01"), ShortRead);
999 do_test!(concat!("fd0001", "00"), InvalidValue);
1000 do_test!(concat!("fd0101"), ShortRead);
1001 do_test!(concat!("0f", "fd"), ShortRead);
1002 do_test!(concat!("0f", "fd26"), ShortRead);
1003 do_test!(concat!("0f", "fd2602"), ShortRead);
1004 do_test!(concat!("0f", "fd0001", "00"), InvalidValue);
1005 do_test!(concat!("0f", "fd0201", "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), ShortRead);
1007 do_test!(concat!("12", "00"), UnknownRequiredFeature);
1008 do_test!(concat!("fd0102", "00"), UnknownRequiredFeature);
1009 do_test!(concat!("fe01000002", "00"), UnknownRequiredFeature);
1010 do_test!(concat!("ff0100000000000002", "00"), UnknownRequiredFeature);
1014 fn bolt_tlv_bogus_n1_stream() {
1015 macro_rules! do_test {
1016 ($stream: expr, $reason: ident) => {
1017 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1018 } else { panic!(); }
1022 // TLVs from the BOLT test cases which should not decode as n1
1023 do_test!(concat!("01", "09", "ffffffffffffffffff"), InvalidValue);
1024 do_test!(concat!("01", "01", "00"), InvalidValue);
1025 do_test!(concat!("01", "02", "0001"), InvalidValue);
1026 do_test!(concat!("01", "03", "000100"), InvalidValue);
1027 do_test!(concat!("01", "04", "00010000"), InvalidValue);
1028 do_test!(concat!("01", "05", "0001000000"), InvalidValue);
1029 do_test!(concat!("01", "06", "000100000000"), InvalidValue);
1030 do_test!(concat!("01", "07", "00010000000000"), InvalidValue);
1031 do_test!(concat!("01", "08", "0001000000000000"), InvalidValue);
1032 do_test!(concat!("02", "07", "01010101010101"), ShortRead);
1033 do_test!(concat!("02", "09", "010101010101010101"), InvalidValue);
1034 do_test!(concat!("03", "21", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb"), ShortRead);
1035 do_test!(concat!("03", "29", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001"), ShortRead);
1036 do_test!(concat!("03", "30", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb000000000000000100000000000001"), ShortRead);
1037 do_test!(concat!("03", "31", "043da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"), InvalidValue);
1038 do_test!(concat!("03", "32", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001000000000000000001"), InvalidValue);
1039 do_test!(concat!("fd00fe", "00"), ShortRead);
1040 do_test!(concat!("fd00fe", "01", "01"), ShortRead);
1041 do_test!(concat!("fd00fe", "03", "010101"), InvalidValue);
1042 do_test!(concat!("00", "00"), UnknownRequiredFeature);
1044 do_test!(concat!("02", "08", "0000000000000226", "01", "01", "2a"), InvalidValue);
1045 do_test!(concat!("02", "08", "0000000000000231", "02", "08", "0000000000000451"), InvalidValue);
1046 do_test!(concat!("1f", "00", "0f", "01", "2a"), InvalidValue);
1047 do_test!(concat!("1f", "00", "1f", "01", "2a"), InvalidValue);
1049 // The last BOLT test modified to not require creating a new decoder for one trivial test.
1050 do_test!(concat!("ffffffffffffffffff", "00", "01", "00"), InvalidValue);
1054 fn bolt_tlv_valid_n1_stream() {
1055 macro_rules! do_test {
1056 ($stream: expr, $tlv1: expr, $tlv2: expr, $tlv3: expr, $tlv4: expr) => {
1057 if let Ok((tlv1, tlv2, tlv3, tlv4)) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1058 assert_eq!(tlv1.map(|v| v.0), $tlv1);
1059 assert_eq!(tlv2, $tlv2);
1060 assert_eq!(tlv3, $tlv3);
1061 assert_eq!(tlv4, $tlv4);
1062 } else { panic!(); }
1066 do_test!(concat!(""), None, None, None, None);
1067 do_test!(concat!("21", "00"), None, None, None, None);
1068 do_test!(concat!("fd0201", "00"), None, None, None, None);
1069 do_test!(concat!("fd00fd", "00"), None, None, None, None);
1070 do_test!(concat!("fd00ff", "00"), None, None, None, None);
1071 do_test!(concat!("fe02000001", "00"), None, None, None, None);
1072 do_test!(concat!("ff0200000000000001", "00"), None, None, None, None);
1074 do_test!(concat!("01", "00"), Some(0), None, None, None);
1075 do_test!(concat!("01", "01", "01"), Some(1), None, None, None);
1076 do_test!(concat!("01", "02", "0100"), Some(256), None, None, None);
1077 do_test!(concat!("01", "03", "010000"), Some(65536), None, None, None);
1078 do_test!(concat!("01", "04", "01000000"), Some(16777216), None, None, None);
1079 do_test!(concat!("01", "05", "0100000000"), Some(4294967296), None, None, None);
1080 do_test!(concat!("01", "06", "010000000000"), Some(1099511627776), None, None, None);
1081 do_test!(concat!("01", "07", "01000000000000"), Some(281474976710656), None, None, None);
1082 do_test!(concat!("01", "08", "0100000000000000"), Some(72057594037927936), None, None, None);
1083 do_test!(concat!("02", "08", "0000000000000226"), None, Some((0 << 30) | (0 << 5) | (550 << 0)), None, None);
1084 do_test!(concat!("03", "31", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"),
1086 PublicKey::from_slice(&::hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]).unwrap(), 1, 2)),
1088 do_test!(concat!("fd00fe", "02", "0226"), None, None, None, Some(550));
1091 fn do_simple_test_tlv_write() -> Result<(), io::Error> {
1092 let mut stream = VecWriter(Vec::new());
1095 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, 1u8, required), (42, None::<u64>, option)});
1096 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1099 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, Some(1u8), option)});
1100 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1103 _encode_varint_length_prefixed_tlv!(&mut stream, {(4, 0xabcdu16, required), (42, None::<u64>, option)});
1104 assert_eq!(stream.0, ::hex::decode("040402abcd").unwrap());
1107 _encode_varint_length_prefixed_tlv!(&mut stream, {(42, None::<u64>, option), (0xff, 0xabcdu16, required)});
1108 assert_eq!(stream.0, ::hex::decode("06fd00ff02abcd").unwrap());
1111 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, 1u64, required), (42, None::<u64>, option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1112 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1115 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, Some(1u64), option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1116 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1122 fn simple_test_tlv_write() {
1123 do_simple_test_tlv_write().unwrap();