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 $crate::ln::msgs::DecodeError;
382 let mut last_seen_type: Option<u64> = None;
383 let mut stream_ref = $stream;
385 use $crate::util::ser;
387 // First decode the type of this TLV:
388 let typ: ser::BigSize = {
389 // We track whether any bytes were read during the consensus_decode call to
390 // determine whether we should break or return ShortRead if we get an
391 // UnexpectedEof. This should in every case be largely cosmetic, but its nice to
392 // pass the TLV test vectors exactly, which require this distinction.
393 let mut tracking_reader = ser::ReadTrackingReader::new(&mut stream_ref);
394 match <$crate::util::ser::BigSize as $crate::util::ser::Readable>::read(&mut tracking_reader) {
395 Err(DecodeError::ShortRead) => {
396 if !tracking_reader.have_read {
399 return Err(DecodeError::ShortRead);
402 Err(e) => return Err(e),
403 Ok(t) => if core::ops::RangeBounds::contains(&$range, &t.0) { t } else {
404 drop(tracking_reader);
406 // Assumes the type id is minimally encoded, which is enforced on read.
407 use $crate::util::ser::Writeable;
408 let bytes_read = t.serialized_length();
409 $rewind(stream_ref, bytes_read);
415 // Types must be unique and monotonically increasing:
416 match last_seen_type {
417 Some(t) if typ.0 <= t => {
418 return Err(DecodeError::InvalidValue);
422 // As we read types, make sure we hit every required type between `last_seen_type` and `typ`:
424 $crate::_check_decoded_tlv_order!(last_seen_type, typ, $type, $field, $fieldty);
426 last_seen_type = Some(typ.0);
428 // Finally, read the length and value itself:
429 let length: ser::BigSize = $crate::util::ser::Readable::read(&mut stream_ref)?;
430 let mut s = ser::FixedLengthReader::new(&mut stream_ref, length.0);
432 $(_t if $crate::_decode_tlv_stream_match_check!(_t, $type, $fieldty) => {
433 $crate::_decode_tlv!(s, $field, $fieldty);
434 if s.bytes_remain() {
435 s.eat_remaining()?; // Return ShortRead if there's actually not enough bytes
436 return Err(DecodeError::InvalidValue);
441 if $decode_custom_tlv(t, &mut s)? {
442 // If a custom TLV was successfully read (i.e. decode_custom_tlv returns true),
443 // continue to the next TLV read.
449 return Err(DecodeError::UnknownRequiredFeature);
455 // Make sure we got to each required type after we've read every TLV:
457 $crate::_check_missing_tlv!(last_seen_type, $type, $field, $fieldty);
462 macro_rules! impl_writeable_msg {
463 ($st:ident, {$($field:ident),* $(,)*}, {$(($type: expr, $tlvfield: ident, $fieldty: tt)),* $(,)*}) => {
464 impl $crate::util::ser::Writeable for $st {
465 fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
466 $( self.$field.write(w)?; )*
467 encode_tlv_stream!(w, {$(($type, self.$tlvfield, $fieldty)),*});
471 impl $crate::util::ser::Readable for $st {
472 fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
473 $(let $field = $crate::util::ser::Readable::read(r)?;)*
474 $(_init_tlv_field_var!($tlvfield, $fieldty);)*
475 decode_tlv_stream!(r, {$(($type, $tlvfield, $fieldty)),*});
485 macro_rules! impl_writeable {
486 ($st:ident, {$($field:ident),*}) => {
487 impl $crate::util::ser::Writeable for $st {
488 fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
489 $( self.$field.write(w)?; )*
494 fn serialized_length(&self) -> usize {
495 let mut len_calc = 0;
496 $( len_calc += self.$field.serialized_length(); )*
501 impl $crate::util::ser::Readable for $st {
502 fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
504 $($field: $crate::util::ser::Readable::read(r)?),*
511 /// Write out two bytes to indicate the version of an object.
513 /// $this_version represents a unique version of a type. Incremented whenever the type's
514 /// serialization format has changed or has a new interpretation. Used by a type's reader to
515 /// determine how to interpret fields or if it can understand a serialized object.
517 /// $min_version_that_can_read_this is the minimum reader version which can understand this
518 /// serialized object. Previous versions will simply err with a [`DecodeError::UnknownVersion`].
520 /// Updates to either `$this_version` or `$min_version_that_can_read_this` should be included in
523 /// Both version fields can be specific to this type of object.
525 /// [`DecodeError::UnknownVersion`]: crate::ln::msgs::DecodeError::UnknownVersion
526 macro_rules! write_ver_prefix {
527 ($stream: expr, $this_version: expr, $min_version_that_can_read_this: expr) => {
528 $stream.write_all(&[$this_version; 1])?;
529 $stream.write_all(&[$min_version_that_can_read_this; 1])?;
533 /// Writes out a suffix to an object as a length-prefixed TLV stream which contains potentially
534 /// backwards-compatible, optional fields which old nodes can happily ignore.
536 /// It is written out in TLV format and, as with all TLV fields, unknown even fields cause a
537 /// [`DecodeError::UnknownRequiredFeature`] error, with unknown odd fields ignored.
539 /// This is the preferred method of adding new fields that old nodes can ignore and still function
542 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
544 macro_rules! write_tlv_fields {
545 ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => {
546 $crate::_encode_varint_length_prefixed_tlv!($stream, {$(($type, $field, $fieldty)),*})
550 /// Reads a prefix added by [`write_ver_prefix`], above. Takes the current version of the
551 /// serialization logic for this object. This is compared against the
552 /// `$min_version_that_can_read_this` added by [`write_ver_prefix`].
553 macro_rules! read_ver_prefix {
554 ($stream: expr, $this_version: expr) => { {
555 let ver: u8 = Readable::read($stream)?;
556 let min_ver: u8 = Readable::read($stream)?;
557 if min_ver > $this_version {
558 return Err(DecodeError::UnknownVersion);
564 /// Reads a suffix added by [`write_tlv_fields`].
566 /// [`write_tlv_fields`]: crate::write_tlv_fields
568 macro_rules! read_tlv_fields {
569 ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => { {
570 let tlv_len: $crate::util::ser::BigSize = $crate::util::ser::Readable::read($stream)?;
571 let mut rd = $crate::util::ser::FixedLengthReader::new($stream, tlv_len.0);
572 $crate::decode_tlv_stream!(&mut rd, {$(($type, $field, $fieldty)),*});
573 rd.eat_remaining().map_err(|_| $crate::ln::msgs::DecodeError::ShortRead)?;
577 /// Initializes the struct fields.
579 /// This is exported for use by other exported macros, do not use directly.
582 macro_rules! _init_tlv_based_struct_field {
583 ($field: ident, (default_value, $default: expr)) => {
586 ($field: ident, (static_value, $value: expr)) => {
589 ($field: ident, option) => {
592 ($field: ident, ignorable) => {
593 if $field.is_none() { return Ok(None); } else { $field.unwrap() }
595 ($field: ident, required) => {
598 ($field: ident, vec_type) => {
603 /// Initializes the variable we are going to read the TLV into.
605 /// This is exported for use by other exported macros, do not use directly.
608 macro_rules! _init_tlv_field_var {
609 ($field: ident, (default_value, $default: expr)) => {
610 let mut $field = $crate::util::ser::OptionDeserWrapper(None);
612 ($field: ident, (static_value, $value: expr)) => {
615 ($field: ident, required) => {
616 let mut $field = $crate::util::ser::OptionDeserWrapper(None);
618 ($field: ident, vec_type) => {
619 let mut $field = Some(Vec::new());
621 ($field: ident, option) => {
622 let mut $field = None;
624 ($field: ident, ignorable) => {
625 let mut $field = None;
629 /// Equivalent to running [`_init_tlv_field_var`] then [`read_tlv_fields`].
631 /// This is exported for use by other exported macros, do not use directly.
634 macro_rules! _init_and_read_tlv_fields {
635 ($reader: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
637 $crate::_init_tlv_field_var!($field, $fieldty);
640 $crate::read_tlv_fields!($reader, {
641 $(($type, $field, $fieldty)),*
646 /// Implements [`Readable`]/[`Writeable`] for a struct storing it as a set of TLVs
647 /// If `$fieldty` is `required`, then `$field` is a required field that is not an Option nor a Vec.
648 /// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
649 /// If `$fieldty` is `option`, then `$field` is optional field.
650 /// If `$fieldty` is `vec_type`, then `$field` is a Vec, which needs to have its individual elements serialized.
654 /// # use lightning::impl_writeable_tlv_based;
655 /// struct LightningMessage {
656 /// tlv_integer: u32,
657 /// tlv_default_integer: u32,
658 /// tlv_optional_integer: Option<u32>,
659 /// tlv_vec_type_integer: Vec<u32>,
662 /// impl_writeable_tlv_based!(LightningMessage, {
663 /// (0, tlv_integer, required),
664 /// (1, tlv_default_integer, (default_value, 7)),
665 /// (2, tlv_optional_integer, option),
666 /// (3, tlv_vec_type_integer, vec_type),
670 /// [`Readable`]: crate::util::ser::Readable
671 /// [`Writeable`]: crate::util::ser::Writeable
673 macro_rules! impl_writeable_tlv_based {
674 ($st: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
675 impl $crate::util::ser::Writeable for $st {
676 fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
677 $crate::write_tlv_fields!(writer, {
678 $(($type, self.$field, $fieldty)),*
684 fn serialized_length(&self) -> usize {
685 use $crate::util::ser::BigSize;
688 let mut len = $crate::util::ser::LengthCalculatingWriter(0);
690 $crate::_get_varint_length_prefixed_tlv_length!(len, $type, self.$field, $fieldty);
694 let mut len_calc = $crate::util::ser::LengthCalculatingWriter(0);
695 BigSize(len as u64).write(&mut len_calc).expect("No in-memory data may fail to serialize");
700 impl $crate::util::ser::Readable for $st {
701 fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
702 $crate::_init_and_read_tlv_fields!(reader, {
703 $(($type, $field, $fieldty)),*
707 $field: $crate::_init_tlv_based_struct_field!($field, $fieldty)
715 /// Defines a struct for a TLV stream and a similar struct using references for non-primitive types,
716 /// implementing [`Readable`] for the former and [`Writeable`] for the latter. Useful as an
717 /// intermediary format when reading or writing a type encoded as a TLV stream. Note that each field
718 /// representing a TLV record has its type wrapped with an [`Option`]. A tuple consisting of a type
719 /// and a serialization wrapper may be given in place of a type when custom serialization is
722 /// [`Readable`]: crate::util::ser::Readable
723 /// [`Writeable`]: crate::util::ser::Writeable
724 macro_rules! tlv_stream {
725 ($name:ident, $nameref:ident, $range:expr, {
726 $(($type:expr, $field:ident : $fieldty:tt)),* $(,)*
729 pub(super) struct $name {
731 pub(super) $field: Option<tlv_record_type!($fieldty)>,
735 #[cfg_attr(test, derive(PartialEq))]
737 pub(super) struct $nameref<'a> {
739 pub(super) $field: Option<tlv_record_ref_type!($fieldty)>,
743 impl<'a> $crate::util::ser::Writeable for $nameref<'a> {
744 fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
745 encode_tlv_stream!(writer, {
746 $(($type, self.$field, (option, encoding: $fieldty))),*
752 impl $crate::util::ser::SeekReadable for $name {
753 fn read<R: $crate::io::Read + $crate::io::Seek>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
755 _init_tlv_field_var!($field, option);
757 let rewind = |cursor: &mut R, offset: usize| {
758 cursor.seek($crate::io::SeekFrom::Current(-(offset as i64))).expect("");
760 _decode_tlv_stream_range!(reader, $range, rewind, {
761 $(($type, $field, (option, encoding: $fieldty))),*
774 macro_rules! tlv_record_type {
775 (($type:ty, $wrapper:ident)) => { $type };
776 (($type:ty, $wrapper:ident, $encoder:ty)) => { $type };
777 ($type:ty) => { $type };
780 macro_rules! tlv_record_ref_type {
783 ((u16, $wrapper: ident)) => { u16 };
784 ((u32, $wrapper: ident)) => { u32 };
785 ((u64, $wrapper: ident)) => { u64 };
786 (($type:ty, $wrapper:ident)) => { &'a $type };
787 (($type:ty, $wrapper:ident, $encoder:ty)) => { $encoder };
788 ($type:ty) => { &'a $type };
791 macro_rules! _impl_writeable_tlv_based_enum_common {
792 ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
793 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
795 $(($tuple_variant_id: expr, $tuple_variant_name: ident)),* $(,)*) => {
796 impl $crate::util::ser::Writeable for $st {
797 fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
799 $($st::$variant_name { $(ref $field),* } => {
800 let id: u8 = $variant_id;
802 write_tlv_fields!(writer, {
803 $(($type, *$field, $fieldty)),*
806 $($st::$tuple_variant_name (ref field) => {
807 let id: u8 = $tuple_variant_id;
809 field.write(writer)?;
818 /// Implement [`Readable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and tuple
819 /// variants stored directly.
820 /// The format is, for example
822 /// impl_writeable_tlv_based_enum!(EnumName,
823 /// (0, StructVariantA) => {(0, required_variant_field, required), (1, optional_variant_field, option)},
824 /// (1, StructVariantB) => {(0, variant_field_a, required), (1, variant_field_b, required), (2, variant_vec_field, vec_type)};
825 /// (2, TupleVariantA), (3, TupleVariantB),
828 /// The type is written as a single byte, followed by any variant data.
829 /// Attempts to read an unknown type byte result in [`DecodeError::UnknownRequiredFeature`].
831 /// [`Readable`]: crate::util::ser::Readable
832 /// [`Writeable`]: crate::util::ser::Writeable
833 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
835 macro_rules! impl_writeable_tlv_based_enum {
836 ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
837 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
839 $(($tuple_variant_id: expr, $tuple_variant_name: ident)),* $(,)*) => {
840 _impl_writeable_tlv_based_enum_common!($st,
841 $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
842 $(($tuple_variant_id, $tuple_variant_name)),*);
844 impl $crate::util::ser::Readable for $st {
845 fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
846 let id: u8 = $crate::util::ser::Readable::read(reader)?;
849 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
850 // in the same function body. Instead, we define a closure and call it.
852 _init_and_read_tlv_fields!(reader, {
853 $(($type, $field, $fieldty)),*
855 Ok($st::$variant_name {
857 $field: _init_tlv_based_struct_field!($field, $fieldty)
863 $($tuple_variant_id => {
864 Ok($st::$tuple_variant_name(Readable::read(reader)?))
867 Err($crate::ln::msgs::DecodeError::UnknownRequiredFeature)
875 /// Implement [`MaybeReadable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and
876 /// tuple variants stored directly.
878 /// This is largely identical to [`impl_writeable_tlv_based_enum`], except that odd variants will
879 /// return `Ok(None)` instead of `Err(`[`DecodeError::UnknownRequiredFeature`]`)`. It should generally be preferred
880 /// when [`MaybeReadable`] is practical instead of just [`Readable`] as it provides an upgrade path for
881 /// new variants to be added which are simply ignored by existing clients.
883 /// [`MaybeReadable`]: crate::util::ser::MaybeReadable
884 /// [`Writeable`]: crate::util::ser::Writeable
885 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
886 /// [`Readable`]: crate::util::ser::Readable
888 macro_rules! impl_writeable_tlv_based_enum_upgradable {
889 ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
890 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
893 $(($tuple_variant_id: expr, $tuple_variant_name: ident)),* $(,)*)*) => {
894 _impl_writeable_tlv_based_enum_common!($st,
895 $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
896 $($(($tuple_variant_id, $tuple_variant_name)),*)*);
898 impl $crate::util::ser::MaybeReadable for $st {
899 fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Option<Self>, $crate::ln::msgs::DecodeError> {
900 let id: u8 = $crate::util::ser::Readable::read(reader)?;
903 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
904 // in the same function body. Instead, we define a closure and call it.
906 _init_and_read_tlv_fields!(reader, {
907 $(($type, $field, $fieldty)),*
909 Ok(Some($st::$variant_name {
911 $field: _init_tlv_based_struct_field!($field, $fieldty)
917 $($($tuple_variant_id => {
918 Ok(Some($st::$tuple_variant_name(Readable::read(reader)?)))
920 _ if id % 2 == 1 => Ok(None),
921 _ => Err(DecodeError::UnknownRequiredFeature),
930 use crate::io::{self, Cursor};
931 use crate::prelude::*;
932 use crate::ln::msgs::DecodeError;
933 use crate::util::ser::{Writeable, HighZeroBytesDroppedBigSize, VecWriter};
934 use bitcoin::secp256k1::PublicKey;
936 // The BOLT TLV test cases don't include any tests which use our "required-value" logic since
937 // the encoding layer in the BOLTs has no such concept, though it makes our macros easier to
938 // work with so they're baked into the decoder. Thus, we have a few additional tests below
939 fn tlv_reader(s: &[u8]) -> Result<(u64, u32, Option<u32>), DecodeError> {
940 let mut s = Cursor::new(s);
943 let mut c: Option<u32> = None;
944 decode_tlv_stream!(&mut s, {(2, a, required), (3, b, required), (4, c, option)});
949 fn tlv_v_short_read() {
950 // We only expect a u32 for type 3 (which we are given), but the L says its 8 bytes.
951 if let Err(DecodeError::ShortRead) = tlv_reader(&::hex::decode(
952 concat!("0100", "0208deadbeef1badbeef", "0308deadbeef")
958 fn tlv_types_out_of_order() {
959 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
960 concat!("0100", "0304deadbeef", "0208deadbeef1badbeef")
963 // ...even if its some field we don't understand
964 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
965 concat!("0208deadbeef1badbeef", "0100", "0304deadbeef")
971 fn tlv_req_type_missing_or_extra() {
972 // It's also bad if they included even fields we don't understand
973 if let Err(DecodeError::UnknownRequiredFeature) = tlv_reader(&::hex::decode(
974 concat!("0100", "0208deadbeef1badbeef", "0304deadbeef", "0600")
977 // ... or if they're missing fields we need
978 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
979 concat!("0100", "0208deadbeef1badbeef")
982 // ... even if that field is even
983 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
984 concat!("0304deadbeef", "0500")
990 fn tlv_simple_good_cases() {
991 assert_eq!(tlv_reader(&::hex::decode(
992 concat!("0208deadbeef1badbeef", "03041bad1dea")
993 ).unwrap()[..]).unwrap(),
994 (0xdeadbeef1badbeef, 0x1bad1dea, None));
995 assert_eq!(tlv_reader(&::hex::decode(
996 concat!("0208deadbeef1badbeef", "03041bad1dea", "040401020304")
997 ).unwrap()[..]).unwrap(),
998 (0xdeadbeef1badbeef, 0x1bad1dea, Some(0x01020304)));
1001 // BOLT TLV test cases
1002 fn tlv_reader_n1(s: &[u8]) -> Result<(Option<HighZeroBytesDroppedBigSize<u64>>, Option<u64>, Option<(PublicKey, u64, u64)>, Option<u16>), DecodeError> {
1003 let mut s = Cursor::new(s);
1004 let mut tlv1: Option<HighZeroBytesDroppedBigSize<u64>> = None;
1005 let mut tlv2: Option<u64> = None;
1006 let mut tlv3: Option<(PublicKey, u64, u64)> = None;
1007 let mut tlv4: Option<u16> = None;
1008 decode_tlv_stream!(&mut s, {(1, tlv1, option), (2, tlv2, option), (3, tlv3, option), (254, tlv4, option)});
1009 Ok((tlv1, tlv2, tlv3, tlv4))
1013 fn bolt_tlv_bogus_stream() {
1014 macro_rules! do_test {
1015 ($stream: expr, $reason: ident) => {
1016 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1017 } else { panic!(); }
1021 // TLVs from the BOLT test cases which should not decode as either n1 or n2
1022 do_test!(concat!("fd01"), ShortRead);
1023 do_test!(concat!("fd0001", "00"), InvalidValue);
1024 do_test!(concat!("fd0101"), ShortRead);
1025 do_test!(concat!("0f", "fd"), ShortRead);
1026 do_test!(concat!("0f", "fd26"), ShortRead);
1027 do_test!(concat!("0f", "fd2602"), ShortRead);
1028 do_test!(concat!("0f", "fd0001", "00"), InvalidValue);
1029 do_test!(concat!("0f", "fd0201", "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), ShortRead);
1031 do_test!(concat!("12", "00"), UnknownRequiredFeature);
1032 do_test!(concat!("fd0102", "00"), UnknownRequiredFeature);
1033 do_test!(concat!("fe01000002", "00"), UnknownRequiredFeature);
1034 do_test!(concat!("ff0100000000000002", "00"), UnknownRequiredFeature);
1038 fn bolt_tlv_bogus_n1_stream() {
1039 macro_rules! do_test {
1040 ($stream: expr, $reason: ident) => {
1041 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1042 } else { panic!(); }
1046 // TLVs from the BOLT test cases which should not decode as n1
1047 do_test!(concat!("01", "09", "ffffffffffffffffff"), InvalidValue);
1048 do_test!(concat!("01", "01", "00"), InvalidValue);
1049 do_test!(concat!("01", "02", "0001"), InvalidValue);
1050 do_test!(concat!("01", "03", "000100"), InvalidValue);
1051 do_test!(concat!("01", "04", "00010000"), InvalidValue);
1052 do_test!(concat!("01", "05", "0001000000"), InvalidValue);
1053 do_test!(concat!("01", "06", "000100000000"), InvalidValue);
1054 do_test!(concat!("01", "07", "00010000000000"), InvalidValue);
1055 do_test!(concat!("01", "08", "0001000000000000"), InvalidValue);
1056 do_test!(concat!("02", "07", "01010101010101"), ShortRead);
1057 do_test!(concat!("02", "09", "010101010101010101"), InvalidValue);
1058 do_test!(concat!("03", "21", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb"), ShortRead);
1059 do_test!(concat!("03", "29", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001"), ShortRead);
1060 do_test!(concat!("03", "30", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb000000000000000100000000000001"), ShortRead);
1061 do_test!(concat!("03", "31", "043da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"), InvalidValue);
1062 do_test!(concat!("03", "32", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001000000000000000001"), InvalidValue);
1063 do_test!(concat!("fd00fe", "00"), ShortRead);
1064 do_test!(concat!("fd00fe", "01", "01"), ShortRead);
1065 do_test!(concat!("fd00fe", "03", "010101"), InvalidValue);
1066 do_test!(concat!("00", "00"), UnknownRequiredFeature);
1068 do_test!(concat!("02", "08", "0000000000000226", "01", "01", "2a"), InvalidValue);
1069 do_test!(concat!("02", "08", "0000000000000231", "02", "08", "0000000000000451"), InvalidValue);
1070 do_test!(concat!("1f", "00", "0f", "01", "2a"), InvalidValue);
1071 do_test!(concat!("1f", "00", "1f", "01", "2a"), InvalidValue);
1073 // The last BOLT test modified to not require creating a new decoder for one trivial test.
1074 do_test!(concat!("ffffffffffffffffff", "00", "01", "00"), InvalidValue);
1078 fn bolt_tlv_valid_n1_stream() {
1079 macro_rules! do_test {
1080 ($stream: expr, $tlv1: expr, $tlv2: expr, $tlv3: expr, $tlv4: expr) => {
1081 if let Ok((tlv1, tlv2, tlv3, tlv4)) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1082 assert_eq!(tlv1.map(|v| v.0), $tlv1);
1083 assert_eq!(tlv2, $tlv2);
1084 assert_eq!(tlv3, $tlv3);
1085 assert_eq!(tlv4, $tlv4);
1086 } else { panic!(); }
1090 do_test!(concat!(""), None, None, None, None);
1091 do_test!(concat!("21", "00"), None, None, None, None);
1092 do_test!(concat!("fd0201", "00"), None, None, None, None);
1093 do_test!(concat!("fd00fd", "00"), None, None, None, None);
1094 do_test!(concat!("fd00ff", "00"), None, None, None, None);
1095 do_test!(concat!("fe02000001", "00"), None, None, None, None);
1096 do_test!(concat!("ff0200000000000001", "00"), None, None, None, None);
1098 do_test!(concat!("01", "00"), Some(0), None, None, None);
1099 do_test!(concat!("01", "01", "01"), Some(1), None, None, None);
1100 do_test!(concat!("01", "02", "0100"), Some(256), None, None, None);
1101 do_test!(concat!("01", "03", "010000"), Some(65536), None, None, None);
1102 do_test!(concat!("01", "04", "01000000"), Some(16777216), None, None, None);
1103 do_test!(concat!("01", "05", "0100000000"), Some(4294967296), None, None, None);
1104 do_test!(concat!("01", "06", "010000000000"), Some(1099511627776), None, None, None);
1105 do_test!(concat!("01", "07", "01000000000000"), Some(281474976710656), None, None, None);
1106 do_test!(concat!("01", "08", "0100000000000000"), Some(72057594037927936), None, None, None);
1107 do_test!(concat!("02", "08", "0000000000000226"), None, Some((0 << 30) | (0 << 5) | (550 << 0)), None, None);
1108 do_test!(concat!("03", "31", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"),
1110 PublicKey::from_slice(&::hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]).unwrap(), 1, 2)),
1112 do_test!(concat!("fd00fe", "02", "0226"), None, None, None, Some(550));
1115 fn do_simple_test_tlv_write() -> Result<(), io::Error> {
1116 let mut stream = VecWriter(Vec::new());
1119 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, 1u8, required), (42, None::<u64>, option)});
1120 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1123 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, Some(1u8), option)});
1124 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1127 _encode_varint_length_prefixed_tlv!(&mut stream, {(4, 0xabcdu16, required), (42, None::<u64>, option)});
1128 assert_eq!(stream.0, ::hex::decode("040402abcd").unwrap());
1131 _encode_varint_length_prefixed_tlv!(&mut stream, {(42, None::<u64>, option), (0xff, 0xabcdu16, required)});
1132 assert_eq!(stream.0, ::hex::decode("06fd00ff02abcd").unwrap());
1135 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, 1u64, required), (42, None::<u64>, option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1136 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1139 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, Some(1u64), option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1140 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1146 fn simple_test_tlv_write() {
1147 do_simple_test_tlv_write().unwrap();