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, ignorable) => {
43 $crate::_encode_tlv!($stream, $type, $field, required);
45 ($stream: expr, $type: expr, $field: expr, (option, encoding: ($fieldty: ty, $encoding: ident))) => {
46 $crate::_encode_tlv!($stream, $type, $field.map(|f| $encoding(f)), option);
48 ($stream: expr, $type: expr, $field: expr, (option, encoding: $fieldty: ty)) => {
49 $crate::_encode_tlv!($stream, $type, $field, option);
53 /// Panics if the last seen TLV type is not numerically less than the TLV type currently being checked.
54 /// This is exported for use by other exported macros, do not use directly.
57 macro_rules! _check_encoded_tlv_order {
58 ($last_type: expr, $type: expr, (static_value, $value: expr)) => { };
59 ($last_type: expr, $type: expr, $fieldty: tt) => {
60 if let Some(t) = $last_type {
61 #[allow(unused_comparisons)] // Note that $type may be 0 making the following comparison always false
62 (debug_assert!(t < $type))
64 $last_type = Some($type);
68 /// Implements the TLVs serialization part in a [`Writeable`] implementation of a struct.
70 /// This should be called inside a method which returns `Result<_, `[`io::Error`]`>`, such as
71 /// [`Writeable::write`]. It will only return an `Err` if the stream `Err`s or [`Writeable::write`]
72 /// on one of the fields `Err`s.
74 /// `$stream` must be a `&mut `[`Writer`] which will receive the bytes for each TLV in the stream.
76 /// Fields MUST be sorted in `$type`-order.
78 /// Note that the lightning TLV requirements require that a single type not appear more than once,
79 /// that TLVs are sorted in type-ascending order, and that any even types be understood by the
82 /// Any `option` fields which have a value of `None` will not be serialized at all.
86 /// # use lightning::encode_tlv_stream;
87 /// # fn write<W: lightning::util::ser::Writer> (stream: &mut W) -> Result<(), lightning::io::Error> {
88 /// let mut required_value = 0u64;
89 /// let mut optional_value: Option<u64> = None;
90 /// encode_tlv_stream!(stream, {
91 /// (0, required_value, required),
92 /// (1, Some(42u64), option),
93 /// (2, optional_value, option),
95 /// // At this point `required_value` has been written as a TLV of type 0, `42u64` has been written
96 /// // as a TLV of type 1 (indicating the reader may ignore it if it is not understood), and *no*
97 /// // TLV is written with type 2.
102 /// [`Writeable`]: crate::util::ser::Writeable
103 /// [`io::Error`]: crate::io::Error
104 /// [`Writeable::write`]: crate::util::ser::Writeable::write
105 /// [`Writer`]: crate::util::ser::Writer
107 macro_rules! encode_tlv_stream {
108 ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => { {
109 #[allow(unused_imports)]
111 ln::msgs::DecodeError,
114 util::ser::Writeable,
118 $crate::_encode_tlv!($stream, $type, $field, $fieldty);
121 #[allow(unused_mut, unused_variables, unused_assignments)]
122 #[cfg(debug_assertions)]
124 let mut last_seen: Option<u64> = None;
126 $crate::_check_encoded_tlv_order!(last_seen, $type, $fieldty);
132 /// Adds the length of the serialized field to a [`LengthCalculatingWriter`].
133 /// This is exported for use by other exported macros, do not use directly.
135 /// [`LengthCalculatingWriter`]: crate::util::ser::LengthCalculatingWriter
138 macro_rules! _get_varint_length_prefixed_tlv_length {
139 ($len: expr, $type: expr, $field: expr, (default_value, $default: expr)) => {
140 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
142 ($len: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
144 ($len: expr, $type: expr, $field: expr, required) => {
145 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
146 let field_len = $field.serialized_length();
147 BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
150 ($len: expr, $type: expr, $field: expr, vec_type) => {
151 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $crate::util::ser::WithoutLength(&$field), required);
153 ($len: expr, $optional_type: expr, $optional_field: expr, option) => {
154 if let Some(ref field) = $optional_field {
155 BigSize($optional_type).write(&mut $len).expect("No in-memory data may fail to serialize");
156 let field_len = field.serialized_length();
157 BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
161 ($len: expr, $type: expr, $field: expr, ignorable) => {
162 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required);
166 /// See the documentation of [`write_tlv_fields`].
167 /// This is exported for use by other exported macros, do not use directly.
170 macro_rules! _encode_varint_length_prefixed_tlv {
171 ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),*}) => { {
172 use $crate::util::ser::BigSize;
175 let mut len = $crate::util::ser::LengthCalculatingWriter(0);
177 $crate::_get_varint_length_prefixed_tlv_length!(len, $type, $field, $fieldty);
181 BigSize(len as u64).write($stream)?;
182 $crate::encode_tlv_stream!($stream, { $(($type, $field, $fieldty)),* });
186 /// Errors if there are missing required TLV types between the last seen type and the type currently being processed.
187 /// This is exported for use by other exported macros, do not use directly.
190 macro_rules! _check_decoded_tlv_order {
191 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value, $default: expr)) => {{
192 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
193 let invalid_order = ($last_seen_type.is_none() || $last_seen_type.unwrap() < $type) && $typ.0 > $type;
195 $field = $default.into();
198 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {
200 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
201 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
202 let invalid_order = ($last_seen_type.is_none() || $last_seen_type.unwrap() < $type) && $typ.0 > $type;
204 return Err(DecodeError::InvalidValue);
207 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, option) => {{
210 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, vec_type) => {{
213 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, ignorable) => {{
216 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
219 ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (option, encoding: $encoding: tt)) => {{
224 /// Errors if there are missing required TLV types after the last seen type.
225 /// This is exported for use by other exported macros, do not use directly.
228 macro_rules! _check_missing_tlv {
229 ($last_seen_type: expr, $type: expr, $field: ident, (default_value, $default: expr)) => {{
230 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
231 let missing_req_type = $last_seen_type.is_none() || $last_seen_type.unwrap() < $type;
232 if missing_req_type {
233 $field = $default.into();
236 ($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
239 ($last_seen_type: expr, $type: expr, $field: ident, required) => {{
240 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
241 let missing_req_type = $last_seen_type.is_none() || $last_seen_type.unwrap() < $type;
242 if missing_req_type {
243 return Err(DecodeError::InvalidValue);
246 ($last_seen_type: expr, $type: expr, $field: ident, vec_type) => {{
249 ($last_seen_type: expr, $type: expr, $field: ident, option) => {{
252 ($last_seen_type: expr, $type: expr, $field: ident, ignorable) => {{
255 ($last_seen_type: expr, $type: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
258 ($last_seen_type: expr, $type: expr, $field: ident, (option, encoding: $encoding: tt)) => {{
263 /// Implements deserialization for a single TLV record.
264 /// This is exported for use by other exported macros, do not use directly.
267 macro_rules! _decode_tlv {
268 ($reader: expr, $field: ident, (default_value, $default: expr)) => {{
269 $crate::_decode_tlv!($reader, $field, required)
271 ($reader: expr, $field: ident, (static_value, $value: expr)) => {{
273 ($reader: expr, $field: ident, required) => {{
274 $field = $crate::util::ser::Readable::read(&mut $reader)?;
276 ($reader: expr, $field: ident, vec_type) => {{
277 let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::Readable::read(&mut $reader)?;
280 ($reader: expr, $field: ident, option) => {{
281 $field = Some($crate::util::ser::Readable::read(&mut $reader)?);
283 ($reader: expr, $field: ident, ignorable) => {{
284 $field = $crate::util::ser::MaybeReadable::read(&mut $reader)?;
286 ($reader: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
287 $field = Some($trait::read(&mut $reader $(, $read_arg)*)?);
289 ($reader: expr, $field: ident, (option, encoding: ($fieldty: ty, $encoding: ident, $encoder:ty))) => {{
290 $crate::_decode_tlv!($reader, $field, (option, encoding: ($fieldty, $encoding)));
292 ($reader: expr, $field: ident, (option, encoding: ($fieldty: ty, $encoding: ident))) => {{
294 let field: $encoding<$fieldty> = ser::Readable::read(&mut $reader)?;
298 ($reader: expr, $field: ident, (option, encoding: $fieldty: ty)) => {{
299 $crate::_decode_tlv!($reader, $field, option);
303 /// Checks if `$val` matches `$type`.
304 /// This is exported for use by other exported macros, do not use directly.
307 macro_rules! _decode_tlv_stream_match_check {
308 ($val: ident, $type: expr, (static_value, $value: expr)) => { false };
309 ($val: ident, $type: expr, $fieldty: tt) => { $val == $type }
312 /// Implements the TLVs deserialization part in a [`Readable`] implementation of a struct.
314 /// This should be called inside a method which returns `Result<_, `[`DecodeError`]`>`, such as
315 /// [`Readable::read`]. It will either return an `Err` or ensure all `required` fields have been
316 /// read and optionally read `optional` fields.
318 /// `$stream` must be a [`Read`] and will be fully consumed, reading until no more bytes remain
319 /// (i.e. it returns [`DecodeError::ShortRead`]).
321 /// Fields MUST be sorted in `$type`-order.
323 /// Note that the lightning TLV requirements require that a single type not appear more than once,
324 /// that TLVs are sorted in type-ascending order, and that any even types be understood by the
329 /// # use lightning::decode_tlv_stream;
330 /// # fn read<R: lightning::io::Read> (stream: R) -> Result<(), lightning::ln::msgs::DecodeError> {
331 /// let mut required_value = 0u64;
332 /// let mut optional_value: Option<u64> = None;
333 /// decode_tlv_stream!(stream, {
334 /// (0, required_value, required),
335 /// (2, optional_value, option),
337 /// // At this point, `required_value` has been overwritten with the TLV with type 0.
338 /// // `optional_value` may have been overwritten, setting it to `Some` if a TLV with type 2 was
344 /// [`Readable`]: crate::util::ser::Readable
345 /// [`DecodeError`]: crate::ln::msgs::DecodeError
346 /// [`Readable::read`]: crate::util::ser::Readable::read
347 /// [`Read`]: crate::io::Read
348 /// [`DecodeError::ShortRead`]: crate::ln::msgs::DecodeError::ShortRead
350 macro_rules! decode_tlv_stream {
351 ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
352 let rewind = |_, _| { unreachable!() };
353 $crate::_decode_tlv_stream_range!($stream, .., rewind, {$(($type, $field, $fieldty)),*});
357 /// Similar to [`decode_tlv_stream`] with a custom TLV decoding capabilities.
359 /// `$decode_custom_tlv` is a closure that may be optionally provided to handle custom message types.
360 /// If it is provided, it will be called with the custom type and the [`FixedLengthReader`] containing
361 /// the message contents. It should return `Ok(true)` if the custom message is successfully parsed,
362 /// `Ok(false)` if the message type is unknown, and `Err(`[`DecodeError`]`)` if parsing fails.
364 /// [`FixedLengthReader`]: crate::util::ser::FixedLengthReader
365 /// [`DecodeError`]: crate::ln::msgs::DecodeError
366 macro_rules! decode_tlv_stream_with_custom_tlv_decode {
367 ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
368 $(, $decode_custom_tlv: expr)?) => { {
369 let rewind = |_, _| { unreachable!() };
370 _decode_tlv_stream_range!(
371 $stream, .., rewind, {$(($type, $field, $fieldty)),*} $(, $decode_custom_tlv)?
378 macro_rules! _decode_tlv_stream_range {
379 ($stream: expr, $range: expr, $rewind: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
380 $(, $decode_custom_tlv: expr)?) => { {
381 use core::ops::RangeBounds;
382 use $crate::ln::msgs::DecodeError;
383 let mut last_seen_type: Option<u64> = None;
384 let mut stream_ref = $stream;
386 use $crate::util::ser;
388 // First decode the type of this TLV:
389 let typ: ser::BigSize = {
390 // We track whether any bytes were read during the consensus_decode call to
391 // determine whether we should break or return ShortRead if we get an
392 // UnexpectedEof. This should in every case be largely cosmetic, but its nice to
393 // pass the TLV test vectors exactly, which require this distinction.
394 let mut tracking_reader = ser::ReadTrackingReader::new(&mut stream_ref);
395 match <$crate::util::ser::BigSize as $crate::util::ser::Readable>::read(&mut tracking_reader) {
396 Err(DecodeError::ShortRead) => {
397 if !tracking_reader.have_read {
400 return Err(DecodeError::ShortRead);
403 Err(e) => return Err(e),
404 Ok(t) => if $range.contains(&t.0) { t } else {
405 drop(tracking_reader);
407 // Assumes the type id is minimally encoded, which is enforced on read.
408 use $crate::util::ser::Writeable;
409 let bytes_read = t.serialized_length();
410 $rewind(stream_ref, bytes_read);
416 // Types must be unique and monotonically increasing:
417 match last_seen_type {
418 Some(t) if typ.0 <= t => {
419 return Err(DecodeError::InvalidValue);
423 // As we read types, make sure we hit every required type between `last_seen_type` and `typ`:
425 $crate::_check_decoded_tlv_order!(last_seen_type, typ, $type, $field, $fieldty);
427 last_seen_type = Some(typ.0);
429 // Finally, read the length and value itself:
430 let length: ser::BigSize = $crate::util::ser::Readable::read(&mut stream_ref)?;
431 let mut s = ser::FixedLengthReader::new(&mut stream_ref, length.0);
433 $(_t if $crate::_decode_tlv_stream_match_check!(_t, $type, $fieldty) => {
434 $crate::_decode_tlv!(s, $field, $fieldty);
435 if s.bytes_remain() {
436 s.eat_remaining()?; // Return ShortRead if there's actually not enough bytes
437 return Err(DecodeError::InvalidValue);
442 if $decode_custom_tlv(t, &mut s)? {
443 // If a custom TLV was successfully read (i.e. decode_custom_tlv returns true),
444 // continue to the next TLV read.
450 return Err(DecodeError::UnknownRequiredFeature);
456 // Make sure we got to each required type after we've read every TLV:
458 $crate::_check_missing_tlv!(last_seen_type, $type, $field, $fieldty);
463 macro_rules! impl_writeable_msg {
464 ($st:ident, {$($field:ident),* $(,)*}, {$(($type: expr, $tlvfield: ident, $fieldty: tt)),* $(,)*}) => {
465 impl $crate::util::ser::Writeable for $st {
466 fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
467 $( self.$field.write(w)?; )*
468 encode_tlv_stream!(w, {$(($type, self.$tlvfield, $fieldty)),*});
472 impl $crate::util::ser::Readable for $st {
473 fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
474 $(let $field = $crate::util::ser::Readable::read(r)?;)*
475 $(_init_tlv_field_var!($tlvfield, $fieldty);)*
476 decode_tlv_stream!(r, {$(($type, $tlvfield, $fieldty)),*});
486 macro_rules! impl_writeable {
487 ($st:ident, {$($field:ident),*}) => {
488 impl $crate::util::ser::Writeable for $st {
489 fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
490 $( self.$field.write(w)?; )*
495 fn serialized_length(&self) -> usize {
496 let mut len_calc = 0;
497 $( len_calc += self.$field.serialized_length(); )*
502 impl $crate::util::ser::Readable for $st {
503 fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
505 $($field: $crate::util::ser::Readable::read(r)?),*
512 /// Write out two bytes to indicate the version of an object.
514 /// $this_version represents a unique version of a type. Incremented whenever the type's
515 /// serialization format has changed or has a new interpretation. Used by a type's reader to
516 /// determine how to interpret fields or if it can understand a serialized object.
518 /// $min_version_that_can_read_this is the minimum reader version which can understand this
519 /// serialized object. Previous versions will simply err with a [`DecodeError::UnknownVersion`].
521 /// Updates to either `$this_version` or `$min_version_that_can_read_this` should be included in
524 /// Both version fields can be specific to this type of object.
526 /// [`DecodeError::UnknownVersion`]: crate::ln::msgs::DecodeError::UnknownVersion
527 macro_rules! write_ver_prefix {
528 ($stream: expr, $this_version: expr, $min_version_that_can_read_this: expr) => {
529 $stream.write_all(&[$this_version; 1])?;
530 $stream.write_all(&[$min_version_that_can_read_this; 1])?;
534 /// Writes out a suffix to an object as a length-prefixed TLV stream which contains potentially
535 /// backwards-compatible, optional fields which old nodes can happily ignore.
537 /// It is written out in TLV format and, as with all TLV fields, unknown even fields cause a
538 /// [`DecodeError::UnknownRequiredFeature`] error, with unknown odd fields ignored.
540 /// This is the preferred method of adding new fields that old nodes can ignore and still function
543 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
545 macro_rules! write_tlv_fields {
546 ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => {
547 $crate::_encode_varint_length_prefixed_tlv!($stream, {$(($type, $field, $fieldty)),*})
551 /// Reads a prefix added by [`write_ver_prefix`], above. Takes the current version of the
552 /// serialization logic for this object. This is compared against the
553 /// `$min_version_that_can_read_this` added by [`write_ver_prefix`].
554 macro_rules! read_ver_prefix {
555 ($stream: expr, $this_version: expr) => { {
556 let ver: u8 = Readable::read($stream)?;
557 let min_ver: u8 = Readable::read($stream)?;
558 if min_ver > $this_version {
559 return Err(DecodeError::UnknownVersion);
565 /// Reads a suffix added by [`write_tlv_fields`].
567 /// [`write_tlv_fields`]: crate::write_tlv_fields
569 macro_rules! read_tlv_fields {
570 ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => { {
571 let tlv_len: $crate::util::ser::BigSize = $crate::util::ser::Readable::read($stream)?;
572 let mut rd = $crate::util::ser::FixedLengthReader::new($stream, tlv_len.0);
573 $crate::decode_tlv_stream!(&mut rd, {$(($type, $field, $fieldty)),*});
574 rd.eat_remaining().map_err(|_| $crate::ln::msgs::DecodeError::ShortRead)?;
578 /// Initializes the struct fields.
580 /// This is exported for use by other exported macros, do not use directly.
583 macro_rules! _init_tlv_based_struct_field {
584 ($field: ident, (default_value, $default: expr)) => {
587 ($field: ident, (static_value, $value: expr)) => {
590 ($field: ident, option) => {
593 ($field: ident, ignorable) => {
594 if $field.is_none() { return Ok(None); } else { $field.unwrap() }
596 ($field: ident, required) => {
599 ($field: ident, vec_type) => {
604 /// Initializes the variable we are going to read the TLV into.
606 /// This is exported for use by other exported macros, do not use directly.
609 macro_rules! _init_tlv_field_var {
610 ($field: ident, (default_value, $default: expr)) => {
611 let mut $field = $crate::util::ser::OptionDeserWrapper(None);
613 ($field: ident, (static_value, $value: expr)) => {
616 ($field: ident, required) => {
617 let mut $field = $crate::util::ser::OptionDeserWrapper(None);
619 ($field: ident, vec_type) => {
620 let mut $field = Some(Vec::new());
622 ($field: ident, option) => {
623 let mut $field = None;
625 ($field: ident, ignorable) => {
626 let mut $field = None;
630 /// Equivalent to running [`_init_tlv_field_var`] then [`read_tlv_fields`].
632 /// This is exported for use by other exported macros, do not use directly.
635 macro_rules! _init_and_read_tlv_fields {
636 ($reader: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
638 $crate::_init_tlv_field_var!($field, $fieldty);
641 $crate::read_tlv_fields!($reader, {
642 $(($type, $field, $fieldty)),*
647 /// Implements [`Readable`]/[`Writeable`] for a struct storing it as a set of TLVs
648 /// If `$fieldty` is `required`, then `$field` is a required field that is not an Option nor a Vec.
649 /// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
650 /// If `$fieldty` is `option`, then `$field` is optional field.
651 /// If `$fieldty` is `vec_type`, then `$field` is a Vec, which needs to have its individual elements serialized.
655 /// # use lightning::impl_writeable_tlv_based;
656 /// struct LightningMessage {
657 /// tlv_integer: u32,
658 /// tlv_default_integer: u32,
659 /// tlv_optional_integer: Option<u32>,
660 /// tlv_vec_type_integer: Vec<u32>,
663 /// impl_writeable_tlv_based!(LightningMessage, {
664 /// (0, tlv_integer, required),
665 /// (1, tlv_default_integer, (default_value, 7)),
666 /// (2, tlv_optional_integer, option),
667 /// (3, tlv_vec_type_integer, vec_type),
671 /// [`Readable`]: crate::util::ser::Readable
672 /// [`Writeable`]: crate::util::ser::Writeable
674 macro_rules! impl_writeable_tlv_based {
675 ($st: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
676 impl $crate::util::ser::Writeable for $st {
677 fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
678 $crate::write_tlv_fields!(writer, {
679 $(($type, self.$field, $fieldty)),*
685 fn serialized_length(&self) -> usize {
686 use $crate::util::ser::BigSize;
689 let mut len = $crate::util::ser::LengthCalculatingWriter(0);
691 $crate::_get_varint_length_prefixed_tlv_length!(len, $type, self.$field, $fieldty);
695 let mut len_calc = $crate::util::ser::LengthCalculatingWriter(0);
696 BigSize(len as u64).write(&mut len_calc).expect("No in-memory data may fail to serialize");
701 impl $crate::util::ser::Readable for $st {
702 fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
703 $crate::_init_and_read_tlv_fields!(reader, {
704 $(($type, $field, $fieldty)),*
708 $field: $crate::_init_tlv_based_struct_field!($field, $fieldty)
716 /// Defines a struct for a TLV stream and a similar struct using references for non-primitive types,
717 /// implementing [`Readable`] for the former and [`Writeable`] for the latter. Useful as an
718 /// intermediary format when reading or writing a type encoded as a TLV stream. Note that each field
719 /// representing a TLV record has its type wrapped with an [`Option`]. A tuple consisting of a type
720 /// and a serialization wrapper may be given in place of a type when custom serialization is
723 /// [`Readable`]: crate::util::ser::Readable
724 /// [`Writeable`]: crate::util::ser::Writeable
725 macro_rules! tlv_stream {
726 ($name:ident, $nameref:ident, $range:expr, {
727 $(($type:expr, $field:ident : $fieldty:tt)),* $(,)*
730 pub(super) struct $name {
732 pub(super) $field: Option<tlv_record_type!($fieldty)>,
736 #[cfg_attr(test, derive(PartialEq))]
738 pub(super) struct $nameref<'a> {
740 pub(super) $field: Option<tlv_record_ref_type!($fieldty)>,
744 impl<'a> $crate::util::ser::Writeable for $nameref<'a> {
745 fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
746 encode_tlv_stream!(writer, {
747 $(($type, self.$field, (option, encoding: $fieldty))),*
753 impl $crate::util::ser::SeekReadable for $name {
754 fn read<R: $crate::io::Read + $crate::io::Seek>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
756 _init_tlv_field_var!($field, option);
758 let rewind = |cursor: &mut R, offset: usize| {
759 cursor.seek($crate::io::SeekFrom::Current(-(offset as i64))).expect("");
761 _decode_tlv_stream_range!(reader, $range, rewind, {
762 $(($type, $field, (option, encoding: $fieldty))),*
775 macro_rules! tlv_record_type {
776 (($type:ty, $wrapper:ident)) => { $type };
777 (($type:ty, $wrapper:ident, $encoder:ty)) => { $type };
778 ($type:ty) => { $type };
781 macro_rules! tlv_record_ref_type {
784 ((u16, $wrapper: ident)) => { u16 };
785 ((u32, $wrapper: ident)) => { u32 };
786 ((u64, $wrapper: ident)) => { u64 };
787 (($type:ty, $wrapper:ident)) => { &'a $type };
788 (($type:ty, $wrapper:ident, $encoder:ty)) => { $encoder };
789 ($type:ty) => { &'a $type };
792 macro_rules! _impl_writeable_tlv_based_enum_common {
793 ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
794 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
796 $(($tuple_variant_id: expr, $tuple_variant_name: ident)),* $(,)*) => {
797 impl $crate::util::ser::Writeable for $st {
798 fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
800 $($st::$variant_name { $(ref $field),* } => {
801 let id: u8 = $variant_id;
803 write_tlv_fields!(writer, {
804 $(($type, *$field, $fieldty)),*
807 $($st::$tuple_variant_name (ref field) => {
808 let id: u8 = $tuple_variant_id;
810 field.write(writer)?;
819 /// Implement [`Readable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and tuple
820 /// variants stored directly.
821 /// The format is, for example
823 /// impl_writeable_tlv_based_enum!(EnumName,
824 /// (0, StructVariantA) => {(0, required_variant_field, required), (1, optional_variant_field, option)},
825 /// (1, StructVariantB) => {(0, variant_field_a, required), (1, variant_field_b, required), (2, variant_vec_field, vec_type)};
826 /// (2, TupleVariantA), (3, TupleVariantB),
829 /// The type is written as a single byte, followed by any variant data.
830 /// Attempts to read an unknown type byte result in [`DecodeError::UnknownRequiredFeature`].
832 /// [`Readable`]: crate::util::ser::Readable
833 /// [`Writeable`]: crate::util::ser::Writeable
834 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
836 macro_rules! impl_writeable_tlv_based_enum {
837 ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
838 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
840 $(($tuple_variant_id: expr, $tuple_variant_name: ident)),* $(,)*) => {
841 _impl_writeable_tlv_based_enum_common!($st,
842 $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
843 $(($tuple_variant_id, $tuple_variant_name)),*);
845 impl $crate::util::ser::Readable for $st {
846 fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
847 let id: u8 = $crate::util::ser::Readable::read(reader)?;
850 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
851 // in the same function body. Instead, we define a closure and call it.
853 _init_and_read_tlv_fields!(reader, {
854 $(($type, $field, $fieldty)),*
856 Ok($st::$variant_name {
858 $field: _init_tlv_based_struct_field!($field, $fieldty)
864 $($tuple_variant_id => {
865 Ok($st::$tuple_variant_name(Readable::read(reader)?))
868 Err($crate::ln::msgs::DecodeError::UnknownRequiredFeature)
876 /// Implement [`MaybeReadable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and
877 /// tuple variants stored directly.
879 /// This is largely identical to [`impl_writeable_tlv_based_enum`], except that odd variants will
880 /// return `Ok(None)` instead of `Err(`[`DecodeError::UnknownRequiredFeature`]`)`. It should generally be preferred
881 /// when [`MaybeReadable`] is practical instead of just [`Readable`] as it provides an upgrade path for
882 /// new variants to be added which are simply ignored by existing clients.
884 /// [`MaybeReadable`]: crate::util::ser::MaybeReadable
885 /// [`Writeable`]: crate::util::ser::Writeable
886 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
887 /// [`Readable`]: crate::util::ser::Readable
889 macro_rules! impl_writeable_tlv_based_enum_upgradable {
890 ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
891 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
894 $(($tuple_variant_id: expr, $tuple_variant_name: ident)),* $(,)*)*) => {
895 _impl_writeable_tlv_based_enum_common!($st,
896 $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
897 $($(($tuple_variant_id, $tuple_variant_name)),*)*);
899 impl $crate::util::ser::MaybeReadable for $st {
900 fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Option<Self>, $crate::ln::msgs::DecodeError> {
901 let id: u8 = $crate::util::ser::Readable::read(reader)?;
904 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
905 // in the same function body. Instead, we define a closure and call it.
907 _init_and_read_tlv_fields!(reader, {
908 $(($type, $field, $fieldty)),*
910 Ok(Some($st::$variant_name {
912 $field: _init_tlv_based_struct_field!($field, $fieldty)
918 $($($tuple_variant_id => {
919 Ok(Some($st::$tuple_variant_name(Readable::read(reader)?)))
921 _ if id % 2 == 1 => Ok(None),
922 _ => Err(DecodeError::UnknownRequiredFeature),
931 use crate::io::{self, Cursor};
932 use crate::prelude::*;
933 use crate::ln::msgs::DecodeError;
934 use crate::util::ser::{Writeable, HighZeroBytesDroppedBigSize, VecWriter};
935 use bitcoin::secp256k1::PublicKey;
937 // The BOLT TLV test cases don't include any tests which use our "required-value" logic since
938 // the encoding layer in the BOLTs has no such concept, though it makes our macros easier to
939 // work with so they're baked into the decoder. Thus, we have a few additional tests below
940 fn tlv_reader(s: &[u8]) -> Result<(u64, u32, Option<u32>), DecodeError> {
941 let mut s = Cursor::new(s);
944 let mut c: Option<u32> = None;
945 decode_tlv_stream!(&mut s, {(2, a, required), (3, b, required), (4, c, option)});
950 fn tlv_v_short_read() {
951 // We only expect a u32 for type 3 (which we are given), but the L says its 8 bytes.
952 if let Err(DecodeError::ShortRead) = tlv_reader(&::hex::decode(
953 concat!("0100", "0208deadbeef1badbeef", "0308deadbeef")
959 fn tlv_types_out_of_order() {
960 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
961 concat!("0100", "0304deadbeef", "0208deadbeef1badbeef")
964 // ...even if its some field we don't understand
965 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
966 concat!("0208deadbeef1badbeef", "0100", "0304deadbeef")
972 fn tlv_req_type_missing_or_extra() {
973 // It's also bad if they included even fields we don't understand
974 if let Err(DecodeError::UnknownRequiredFeature) = tlv_reader(&::hex::decode(
975 concat!("0100", "0208deadbeef1badbeef", "0304deadbeef", "0600")
978 // ... or if they're missing fields we need
979 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
980 concat!("0100", "0208deadbeef1badbeef")
983 // ... even if that field is even
984 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
985 concat!("0304deadbeef", "0500")
991 fn tlv_simple_good_cases() {
992 assert_eq!(tlv_reader(&::hex::decode(
993 concat!("0208deadbeef1badbeef", "03041bad1dea")
994 ).unwrap()[..]).unwrap(),
995 (0xdeadbeef1badbeef, 0x1bad1dea, None));
996 assert_eq!(tlv_reader(&::hex::decode(
997 concat!("0208deadbeef1badbeef", "03041bad1dea", "040401020304")
998 ).unwrap()[..]).unwrap(),
999 (0xdeadbeef1badbeef, 0x1bad1dea, Some(0x01020304)));
1002 // BOLT TLV test cases
1003 fn tlv_reader_n1(s: &[u8]) -> Result<(Option<HighZeroBytesDroppedBigSize<u64>>, Option<u64>, Option<(PublicKey, u64, u64)>, Option<u16>), DecodeError> {
1004 let mut s = Cursor::new(s);
1005 let mut tlv1: Option<HighZeroBytesDroppedBigSize<u64>> = None;
1006 let mut tlv2: Option<u64> = None;
1007 let mut tlv3: Option<(PublicKey, u64, u64)> = None;
1008 let mut tlv4: Option<u16> = None;
1009 decode_tlv_stream!(&mut s, {(1, tlv1, option), (2, tlv2, option), (3, tlv3, option), (254, tlv4, option)});
1010 Ok((tlv1, tlv2, tlv3, tlv4))
1014 fn bolt_tlv_bogus_stream() {
1015 macro_rules! do_test {
1016 ($stream: expr, $reason: ident) => {
1017 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1018 } else { panic!(); }
1022 // TLVs from the BOLT test cases which should not decode as either n1 or n2
1023 do_test!(concat!("fd01"), ShortRead);
1024 do_test!(concat!("fd0001", "00"), InvalidValue);
1025 do_test!(concat!("fd0101"), ShortRead);
1026 do_test!(concat!("0f", "fd"), ShortRead);
1027 do_test!(concat!("0f", "fd26"), ShortRead);
1028 do_test!(concat!("0f", "fd2602"), ShortRead);
1029 do_test!(concat!("0f", "fd0001", "00"), InvalidValue);
1030 do_test!(concat!("0f", "fd0201", "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), ShortRead);
1032 do_test!(concat!("12", "00"), UnknownRequiredFeature);
1033 do_test!(concat!("fd0102", "00"), UnknownRequiredFeature);
1034 do_test!(concat!("fe01000002", "00"), UnknownRequiredFeature);
1035 do_test!(concat!("ff0100000000000002", "00"), UnknownRequiredFeature);
1039 fn bolt_tlv_bogus_n1_stream() {
1040 macro_rules! do_test {
1041 ($stream: expr, $reason: ident) => {
1042 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1043 } else { panic!(); }
1047 // TLVs from the BOLT test cases which should not decode as n1
1048 do_test!(concat!("01", "09", "ffffffffffffffffff"), InvalidValue);
1049 do_test!(concat!("01", "01", "00"), InvalidValue);
1050 do_test!(concat!("01", "02", "0001"), InvalidValue);
1051 do_test!(concat!("01", "03", "000100"), InvalidValue);
1052 do_test!(concat!("01", "04", "00010000"), InvalidValue);
1053 do_test!(concat!("01", "05", "0001000000"), InvalidValue);
1054 do_test!(concat!("01", "06", "000100000000"), InvalidValue);
1055 do_test!(concat!("01", "07", "00010000000000"), InvalidValue);
1056 do_test!(concat!("01", "08", "0001000000000000"), InvalidValue);
1057 do_test!(concat!("02", "07", "01010101010101"), ShortRead);
1058 do_test!(concat!("02", "09", "010101010101010101"), InvalidValue);
1059 do_test!(concat!("03", "21", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb"), ShortRead);
1060 do_test!(concat!("03", "29", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001"), ShortRead);
1061 do_test!(concat!("03", "30", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb000000000000000100000000000001"), ShortRead);
1062 do_test!(concat!("03", "31", "043da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"), InvalidValue);
1063 do_test!(concat!("03", "32", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001000000000000000001"), InvalidValue);
1064 do_test!(concat!("fd00fe", "00"), ShortRead);
1065 do_test!(concat!("fd00fe", "01", "01"), ShortRead);
1066 do_test!(concat!("fd00fe", "03", "010101"), InvalidValue);
1067 do_test!(concat!("00", "00"), UnknownRequiredFeature);
1069 do_test!(concat!("02", "08", "0000000000000226", "01", "01", "2a"), InvalidValue);
1070 do_test!(concat!("02", "08", "0000000000000231", "02", "08", "0000000000000451"), InvalidValue);
1071 do_test!(concat!("1f", "00", "0f", "01", "2a"), InvalidValue);
1072 do_test!(concat!("1f", "00", "1f", "01", "2a"), InvalidValue);
1074 // The last BOLT test modified to not require creating a new decoder for one trivial test.
1075 do_test!(concat!("ffffffffffffffffff", "00", "01", "00"), InvalidValue);
1079 fn bolt_tlv_valid_n1_stream() {
1080 macro_rules! do_test {
1081 ($stream: expr, $tlv1: expr, $tlv2: expr, $tlv3: expr, $tlv4: expr) => {
1082 if let Ok((tlv1, tlv2, tlv3, tlv4)) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1083 assert_eq!(tlv1.map(|v| v.0), $tlv1);
1084 assert_eq!(tlv2, $tlv2);
1085 assert_eq!(tlv3, $tlv3);
1086 assert_eq!(tlv4, $tlv4);
1087 } else { panic!(); }
1091 do_test!(concat!(""), None, None, None, None);
1092 do_test!(concat!("21", "00"), None, None, None, None);
1093 do_test!(concat!("fd0201", "00"), None, None, None, None);
1094 do_test!(concat!("fd00fd", "00"), None, None, None, None);
1095 do_test!(concat!("fd00ff", "00"), None, None, None, None);
1096 do_test!(concat!("fe02000001", "00"), None, None, None, None);
1097 do_test!(concat!("ff0200000000000001", "00"), None, None, None, None);
1099 do_test!(concat!("01", "00"), Some(0), None, None, None);
1100 do_test!(concat!("01", "01", "01"), Some(1), None, None, None);
1101 do_test!(concat!("01", "02", "0100"), Some(256), None, None, None);
1102 do_test!(concat!("01", "03", "010000"), Some(65536), None, None, None);
1103 do_test!(concat!("01", "04", "01000000"), Some(16777216), None, None, None);
1104 do_test!(concat!("01", "05", "0100000000"), Some(4294967296), None, None, None);
1105 do_test!(concat!("01", "06", "010000000000"), Some(1099511627776), None, None, None);
1106 do_test!(concat!("01", "07", "01000000000000"), Some(281474976710656), None, None, None);
1107 do_test!(concat!("01", "08", "0100000000000000"), Some(72057594037927936), None, None, None);
1108 do_test!(concat!("02", "08", "0000000000000226"), None, Some((0 << 30) | (0 << 5) | (550 << 0)), None, None);
1109 do_test!(concat!("03", "31", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"),
1111 PublicKey::from_slice(&::hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]).unwrap(), 1, 2)),
1113 do_test!(concat!("fd00fe", "02", "0226"), None, None, None, Some(550));
1116 fn do_simple_test_tlv_write() -> Result<(), io::Error> {
1117 let mut stream = VecWriter(Vec::new());
1120 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, 1u8, required), (42, None::<u64>, option)});
1121 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1124 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, Some(1u8), option)});
1125 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1128 _encode_varint_length_prefixed_tlv!(&mut stream, {(4, 0xabcdu16, required), (42, None::<u64>, option)});
1129 assert_eq!(stream.0, ::hex::decode("040402abcd").unwrap());
1132 _encode_varint_length_prefixed_tlv!(&mut stream, {(42, None::<u64>, option), (0xff, 0xabcdu16, required)});
1133 assert_eq!(stream.0, ::hex::decode("06fd00ff02abcd").unwrap());
1136 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, 1u64, required), (42, None::<u64>, option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1137 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1140 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, Some(1u64), option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1141 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1147 fn simple_test_tlv_write() {
1148 do_simple_test_tlv_write().unwrap();