_ Git - rust-lightning/blob - lightning/src/util/ser_macros.rs

   1 // This file is Copyright its original authors, visible in version control
   2 // history.
   3 //
   4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
   5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
   7 // You may not use this file except in accordance with one or both of these
   8 // licenses.
   9
  10 //! Some macros that implement [`Readable`]/[`Writeable`] traits for lightning messages.
  11 //! They also handle serialization and deserialization of TLVs.
  12 //!
  13 //! [`Readable`]: crate::util::ser::Readable
  14 //! [`Writeable`]: crate::util::ser::Writeable
  15
  16 /// Implements serialization for a single TLV record.
  17 /// This is exported for use by other exported macros, do not use directly.
  18 #[doc(hidden)]
  19 #[macro_export]
  20 macro_rules! _encode_tlv {
  21         ($stream: expr, $type: expr, $field: expr, (default_value, $default: expr)) => {
  22                 $crate::_encode_tlv!($stream, $type, $field, required)
  23         };
  24         ($stream: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
  25                 let _ = &$field; // Ensure we "use" the $field
  26         };
  27         ($stream: expr, $type: expr, $field: expr, required) => {
  28                 BigSize($type).write($stream)?;
  29                 BigSize($field.serialized_length() as u64).write($stream)?;
  30                 $field.write($stream)?;
  31         };
  32         ($stream: expr, $type: expr, $field: expr, vec_type) => {
  33                 $crate::_encode_tlv!($stream, $type, $crate::util::ser::WithoutLength(&$field), required);
  34         };
  35         ($stream: expr, $optional_type: expr, $optional_field: expr, option) => {
  36                 if let Some(ref field) = $optional_field {
  37                         BigSize($optional_type).write($stream)?;
  38                         BigSize(field.serialized_length() as u64).write($stream)?;
  39                         field.write($stream)?;
  40                 }
  41         };
  42         ($stream: expr, $type: expr, $field: expr, upgradable_required) => {
  43                 $crate::_encode_tlv!($stream, $type, $field, required);
  44         };
  45         ($stream: expr, $type: expr, $field: expr, upgradable_option) => {
  46                 $crate::_encode_tlv!($stream, $type, $field, option);
  47         };
  48         ($stream: expr, $type: expr, $field: expr, (option, encoding: ($fieldty: ty, $encoding: ident))) => {
  49                 $crate::_encode_tlv!($stream, $type, $field.map(|f| $encoding(f)), option);
  50         };
  51         ($stream: expr, $type: expr, $field: expr, (option, encoding: $fieldty: ty)) => {
  52                 $crate::_encode_tlv!($stream, $type, $field, option);
  53         };
  54 }
  55
  56 /// Panics if the last seen TLV type is not numerically less than the TLV type currently being checked.
  57 /// This is exported for use by other exported macros, do not use directly.
  58 #[doc(hidden)]
  59 #[macro_export]
  60 macro_rules! _check_encoded_tlv_order {
  61         ($last_type: expr, $type: expr, (static_value, $value: expr)) => { };
  62         ($last_type: expr, $type: expr, $fieldty: tt) => {
  63                 if let Some(t) = $last_type {
  64                         #[allow(unused_comparisons)] // Note that $type may be 0 making the following comparison always false
  65                         (debug_assert!(t < $type))
  66                 }
  67                 $last_type = Some($type);
  68         };
  69 }
  70
  71 /// Implements the TLVs serialization part in a [`Writeable`] implementation of a struct.
  72 ///
  73 /// This should be called inside a method which returns `Result<_, `[`io::Error`]`>`, such as
  74 /// [`Writeable::write`]. It will only return an `Err` if the stream `Err`s or [`Writeable::write`]
  75 /// on one of the fields `Err`s.
  76 ///
  77 /// `$stream` must be a `&mut `[`Writer`] which will receive the bytes for each TLV in the stream.
  78 ///
  79 /// Fields MUST be sorted in `$type`-order.
  80 ///
  81 /// Note that the lightning TLV requirements require that a single type not appear more than once,
  82 /// that TLVs are sorted in type-ascending order, and that any even types be understood by the
  83 /// decoder.
  84 ///
  85 /// Any `option` fields which have a value of `None` will not be serialized at all.
  86 ///
  87 /// For example,
  88 /// ```
  89 /// # use lightning::encode_tlv_stream;
  90 /// # fn write<W: lightning::util::ser::Writer> (stream: &mut W) -> Result<(), lightning::io::Error> {
  91 /// let mut required_value = 0u64;
  92 /// let mut optional_value: Option<u64> = None;
  93 /// encode_tlv_stream!(stream, {
  94 ///     (0, required_value, required),
  95 ///     (1, Some(42u64), option),
  96 ///     (2, optional_value, option),
  97 /// });
  98 /// // At this point `required_value` has been written as a TLV of type 0, `42u64` has been written
  99 /// // as a TLV of type 1 (indicating the reader may ignore it if it is not understood), and *no*
 100 /// // TLV is written with type 2.
 101 /// # Ok(())
 102 /// # }
 103 /// ```
 104 ///
 105 /// [`Writeable`]: crate::util::ser::Writeable
 106 /// [`io::Error`]: crate::io::Error
 107 /// [`Writeable::write`]: crate::util::ser::Writeable::write
 108 /// [`Writer`]: crate::util::ser::Writer
 109 #[macro_export]
 110 macro_rules! encode_tlv_stream {
 111         ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => { {
 112                 #[allow(unused_imports)]
 113                 use $crate::{
 114                         ln::msgs::DecodeError,
 115                         util::ser,
 116                         util::ser::BigSize,
 117                         util::ser::Writeable,
 118                 };
 119
 120                 $(
 121                         $crate::_encode_tlv!($stream, $type, $field, $fieldty);
 122                 )*
 123
 124                 #[allow(unused_mut, unused_variables, unused_assignments)]
 125                 #[cfg(debug_assertions)]
 126                 {
 127                         let mut last_seen: Option<u64> = None;
 128                         $(
 129                                 $crate::_check_encoded_tlv_order!(last_seen, $type, $fieldty);
 130                         )*
 131                 }
 132         } }
 133 }
 134
 135 /// Adds the length of the serialized field to a [`LengthCalculatingWriter`].
 136 /// This is exported for use by other exported macros, do not use directly.
 137 ///
 138 /// [`LengthCalculatingWriter`]: crate::util::ser::LengthCalculatingWriter
 139 #[doc(hidden)]
 140 #[macro_export]
 141 macro_rules! _get_varint_length_prefixed_tlv_length {
 142         ($len: expr, $type: expr, $field: expr, (default_value, $default: expr)) => {
 143                 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
 144         };
 145         ($len: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
 146         };
 147         ($len: expr, $type: expr, $field: expr, required) => {
 148                 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
 149                 let field_len = $field.serialized_length();
 150                 BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
 151                 $len.0 += field_len;
 152         };
 153         ($len: expr, $type: expr, $field: expr, vec_type) => {
 154                 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $crate::util::ser::WithoutLength(&$field), required);
 155         };
 156         ($len: expr, $optional_type: expr, $optional_field: expr, option) => {
 157                 if let Some(ref field) = $optional_field {
 158                         BigSize($optional_type).write(&mut $len).expect("No in-memory data may fail to serialize");
 159                         let field_len = field.serialized_length();
 160                         BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
 161                         $len.0 += field_len;
 162                 }
 163         };
 164         ($len: expr, $type: expr, $field: expr, upgradable_required) => {
 165                 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required);
 166         };
 167         ($len: expr, $type: expr, $field: expr, upgradable_option) => {
 168                 $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, option);
 169         };
 170 }
 171
 172 /// See the documentation of [`write_tlv_fields`].
 173 /// This is exported for use by other exported macros, do not use directly.
 174 #[doc(hidden)]
 175 #[macro_export]
 176 macro_rules! _encode_varint_length_prefixed_tlv {
 177         ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),*}) => { {
 178                 use $crate::util::ser::BigSize;
 179                 let len = {
 180                         #[allow(unused_mut)]
 181                         let mut len = $crate::util::ser::LengthCalculatingWriter(0);
 182                         $(
 183                                 $crate::_get_varint_length_prefixed_tlv_length!(len, $type, $field, $fieldty);
 184                         )*
 185                         len.0
 186                 };
 187                 BigSize(len as u64).write($stream)?;
 188                 $crate::encode_tlv_stream!($stream, { $(($type, $field, $fieldty)),* });
 189         } }
 190 }
 191
 192 /// Errors if there are missing required TLV types between the last seen type and the type currently being processed.
 193 /// This is exported for use by other exported macros, do not use directly.
 194 #[doc(hidden)]
 195 #[macro_export]
 196 macro_rules! _check_decoded_tlv_order {
 197         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value, $default: expr)) => {{
 198                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
 199                 let invalid_order = ($last_seen_type.is_none() || $last_seen_type.unwrap() < $type) && $typ.0 > $type;
 200                 if invalid_order {
 201                         $field = $default.into();
 202                 }
 203         }};
 204         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (static_value, $value: expr)) => {
 205         };
 206         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
 207                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
 208                 let invalid_order = ($last_seen_type.is_none() || $last_seen_type.unwrap() < $type) && $typ.0 > $type;
 209                 if invalid_order {
 210                         return Err(DecodeError::InvalidValue);
 211                 }
 212         }};
 213         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, option) => {{
 214                 // no-op
 215         }};
 216         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, vec_type) => {{
 217                 // no-op
 218         }};
 219         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, upgradable_required) => {{
 220                 _check_decoded_tlv_order!($last_seen_type, $typ, $type, $field, required)
 221         }};
 222         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, upgradable_option) => {{
 223                 // no-op
 224         }};
 225         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
 226                 // no-op
 227         }};
 228         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (option, encoding: $encoding: tt)) => {{
 229                 // no-op
 230         }};
 231 }
 232
 233 /// Errors if there are missing required TLV types after the last seen type.
 234 /// This is exported for use by other exported macros, do not use directly.
 235 #[doc(hidden)]
 236 #[macro_export]
 237 macro_rules! _check_missing_tlv {
 238         ($last_seen_type: expr, $type: expr, $field: ident, (default_value, $default: expr)) => {{
 239                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
 240                 let missing_req_type = $last_seen_type.is_none() || $last_seen_type.unwrap() < $type;
 241                 if missing_req_type {
 242                         $field = $default.into();
 243                 }
 244         }};
 245         ($last_seen_type: expr, $type: expr, $field: expr, (static_value, $value: expr)) => {
 246                 $field = $value;
 247         };
 248         ($last_seen_type: expr, $type: expr, $field: ident, required) => {{
 249                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always false
 250                 let missing_req_type = $last_seen_type.is_none() || $last_seen_type.unwrap() < $type;
 251                 if missing_req_type {
 252                         return Err(DecodeError::InvalidValue);
 253                 }
 254         }};
 255         ($last_seen_type: expr, $type: expr, $field: ident, vec_type) => {{
 256                 // no-op
 257         }};
 258         ($last_seen_type: expr, $type: expr, $field: ident, option) => {{
 259                 // no-op
 260         }};
 261         ($last_seen_type: expr, $type: expr, $field: ident, upgradable_required) => {{
 262                 _check_missing_tlv!($last_seen_type, $type, $field, required)
 263         }};
 264         ($last_seen_type: expr, $type: expr, $field: ident, upgradable_option) => {{
 265                 // no-op
 266         }};
 267         ($last_seen_type: expr, $type: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
 268                 // no-op
 269         }};
 270         ($last_seen_type: expr, $type: expr, $field: ident, (option, encoding: $encoding: tt)) => {{
 271                 // no-op
 272         }};
 273 }
 274
 275 /// Implements deserialization for a single TLV record.
 276 /// This is exported for use by other exported macros, do not use directly.
 277 #[doc(hidden)]
 278 #[macro_export]
 279 macro_rules! _decode_tlv {
 280         ($reader: expr, $field: ident, (default_value, $default: expr)) => {{
 281                 $crate::_decode_tlv!($reader, $field, required)
 282         }};
 283         ($reader: expr, $field: ident, (static_value, $value: expr)) => {{
 284         }};
 285         ($reader: expr, $field: ident, required) => {{
 286                 $field = $crate::util::ser::Readable::read(&mut $reader)?;
 287         }};
 288         ($reader: expr, $field: ident, vec_type) => {{
 289                 let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::Readable::read(&mut $reader)?;
 290                 $field = Some(f.0);
 291         }};
 292         ($reader: expr, $field: ident, option) => {{
 293                 $field = Some($crate::util::ser::Readable::read(&mut $reader)?);
 294         }};
 295         // `upgradable_required` indicates we're reading a required TLV that may have been upgraded
 296         // without backwards compat. We'll error if the field is missing, and return `Ok(None)` if the
 297         // field is present but we can no longer understand it.
 298         // Note that this variant can only be used within a `MaybeReadable` read.
 299         ($reader: expr, $field: ident, upgradable_required) => {{
 300                 $field = match $crate::util::ser::MaybeReadable::read(&mut $reader)? {
 301                         Some(res) => res,
 302                         _ => return Ok(None)
 303                 };
 304         }};
 305         // `upgradable_option` indicates we're reading an Option-al TLV that may have been upgraded
 306         // without backwards compat. $field will be None if the TLV is missing or if the field is present
 307         // but we can no longer understand it.
 308         ($reader: expr, $field: ident, upgradable_option) => {{
 309                 $field = $crate::util::ser::MaybeReadable::read(&mut $reader)?;
 310         }};
 311         ($reader: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
 312                 $field = Some($trait::read(&mut $reader $(, $read_arg)*)?);
 313         }};
 314         ($reader: expr, $field: ident, (option, encoding: ($fieldty: ty, $encoding: ident, $encoder:ty))) => {{
 315                 $crate::_decode_tlv!($reader, $field, (option, encoding: ($fieldty, $encoding)));
 316         }};
 317         ($reader: expr, $field: ident, (option, encoding: ($fieldty: ty, $encoding: ident))) => {{
 318                 $field = {
 319                         let field: $encoding<$fieldty> = ser::Readable::read(&mut $reader)?;
 320                         Some(field.0)
 321                 };
 322         }};
 323         ($reader: expr, $field: ident, (option, encoding: $fieldty: ty)) => {{
 324                 $crate::_decode_tlv!($reader, $field, option);
 325         }};
 326 }
 327
 328 /// Checks if `$val` matches `$type`.
 329 /// This is exported for use by other exported macros, do not use directly.
 330 #[doc(hidden)]
 331 #[macro_export]
 332 macro_rules! _decode_tlv_stream_match_check {
 333         ($val: ident, $type: expr, (static_value, $value: expr)) => { false };
 334         ($val: ident, $type: expr, $fieldty: tt) => { $val == $type }
 335 }
 336
 337 /// Implements the TLVs deserialization part in a [`Readable`] implementation of a struct.
 338 ///
 339 /// This should be called inside a method which returns `Result<_, `[`DecodeError`]`>`, such as
 340 /// [`Readable::read`]. It will either return an `Err` or ensure all `required` fields have been
 341 /// read and optionally read `optional` fields.
 342 ///
 343 /// `$stream` must be a [`Read`] and will be fully consumed, reading until no more bytes remain
 344 /// (i.e. it returns [`DecodeError::ShortRead`]).
 345 ///
 346 /// Fields MUST be sorted in `$type`-order.
 347 ///
 348 /// Note that the lightning TLV requirements require that a single type not appear more than once,
 349 /// that TLVs are sorted in type-ascending order, and that any even types be understood by the
 350 /// decoder.
 351 ///
 352 /// For example,
 353 /// ```
 354 /// # use lightning::decode_tlv_stream;
 355 /// # fn read<R: lightning::io::Read> (stream: R) -> Result<(), lightning::ln::msgs::DecodeError> {
 356 /// let mut required_value = 0u64;
 357 /// let mut optional_value: Option<u64> = None;
 358 /// decode_tlv_stream!(stream, {
 359 ///     (0, required_value, required),
 360 ///     (2, optional_value, option),
 361 /// });
 362 /// // At this point, `required_value` has been overwritten with the TLV with type 0.
 363 /// // `optional_value` may have been overwritten, setting it to `Some` if a TLV with type 2 was
 364 /// // present.
 365 /// # Ok(())
 366 /// # }
 367 /// ```
 368 ///
 369 /// [`Readable`]: crate::util::ser::Readable
 370 /// [`DecodeError`]: crate::ln::msgs::DecodeError
 371 /// [`Readable::read`]: crate::util::ser::Readable::read
 372 /// [`Read`]: crate::io::Read
 373 /// [`DecodeError::ShortRead`]: crate::ln::msgs::DecodeError::ShortRead
 374 #[macro_export]
 375 macro_rules! decode_tlv_stream {
 376         ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
 377                 let rewind = |_, _| { unreachable!() };
 378                 $crate::_decode_tlv_stream_range!($stream, .., rewind, {$(($type, $field, $fieldty)),*});
 379         }
 380 }
 381
 382 /// Similar to [`decode_tlv_stream`] with a custom TLV decoding capabilities.
 383 ///
 384 /// `$decode_custom_tlv` is a closure that may be optionally provided to handle custom message types.
 385 /// If it is provided, it will be called with the custom type and the [`FixedLengthReader`] containing
 386 /// the message contents. It should return `Ok(true)` if the custom message is successfully parsed,
 387 /// `Ok(false)` if the message type is unknown, and `Err(`[`DecodeError`]`)` if parsing fails.
 388 ///
 389 /// [`FixedLengthReader`]: crate::util::ser::FixedLengthReader
 390 /// [`DecodeError`]: crate::ln::msgs::DecodeError
 391 macro_rules! decode_tlv_stream_with_custom_tlv_decode {
 392         ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 393          $(, $decode_custom_tlv: expr)?) => { {
 394                 let rewind = |_, _| { unreachable!() };
 395                 _decode_tlv_stream_range!(
 396                         $stream, .., rewind, {$(($type, $field, $fieldty)),*} $(, $decode_custom_tlv)?
 397                 );
 398         } }
 399 }
 400
 401 #[doc(hidden)]
 402 #[macro_export]
 403 macro_rules! _decode_tlv_stream_range {
 404         ($stream: expr, $range: expr, $rewind: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 405          $(, $decode_custom_tlv: expr)?) => { {
 406                 use $crate::ln::msgs::DecodeError;
 407                 let mut last_seen_type: Option<u64> = None;
 408                 let mut stream_ref = $stream;
 409                 'tlv_read: loop {
 410                         use $crate::util::ser;
 411
 412                         // First decode the type of this TLV:
 413                         let typ: ser::BigSize = {
 414                                 // We track whether any bytes were read during the consensus_decode call to
 415                                 // determine whether we should break or return ShortRead if we get an
 416                                 // UnexpectedEof. This should in every case be largely cosmetic, but its nice to
 417                                 // pass the TLV test vectors exactly, which require this distinction.
 418                                 let mut tracking_reader = ser::ReadTrackingReader::new(&mut stream_ref);
 419                                 match <$crate::util::ser::BigSize as $crate::util::ser::Readable>::read(&mut tracking_reader) {
 420                                         Err(DecodeError::ShortRead) => {
 421                                                 if !tracking_reader.have_read {
 422                                                         break 'tlv_read;
 423                                                 } else {
 424                                                         return Err(DecodeError::ShortRead);
 425                                                 }
 426                                         },
 427                                         Err(e) => return Err(e),
 428                                         Ok(t) => if core::ops::RangeBounds::contains(&$range, &t.0) { t } else {
 429                                                 drop(tracking_reader);
 430
 431                                                 // Assumes the type id is minimally encoded, which is enforced on read.
 432                                                 use $crate::util::ser::Writeable;
 433                                                 let bytes_read = t.serialized_length();
 434                                                 $rewind(stream_ref, bytes_read);
 435                                                 break 'tlv_read;
 436                                         },
 437                                 }
 438                         };
 439
 440                         // Types must be unique and monotonically increasing:
 441                         match last_seen_type {
 442                                 Some(t) if typ.0 <= t => {
 443                                         return Err(DecodeError::InvalidValue);
 444                                 },
 445                                 _ => {},
 446                         }
 447                         // As we read types, make sure we hit every required type between `last_seen_type` and `typ`:
 448                         $({
 449                                 $crate::_check_decoded_tlv_order!(last_seen_type, typ, $type, $field, $fieldty);
 450                         })*
 451                         last_seen_type = Some(typ.0);
 452
 453                         // Finally, read the length and value itself:
 454                         let length: ser::BigSize = $crate::util::ser::Readable::read(&mut stream_ref)?;
 455                         let mut s = ser::FixedLengthReader::new(&mut stream_ref, length.0);
 456                         match typ.0 {
 457                                 $(_t if $crate::_decode_tlv_stream_match_check!(_t, $type, $fieldty) => {
 458                                         $crate::_decode_tlv!(s, $field, $fieldty);
 459                                         if s.bytes_remain() {
 460                                                 s.eat_remaining()?; // Return ShortRead if there's actually not enough bytes
 461                                                 return Err(DecodeError::InvalidValue);
 462                                         }
 463                                 },)*
 464                                 t => {
 465                                         $(
 466                                                 if $decode_custom_tlv(t, &mut s)? {
 467                                                         // If a custom TLV was successfully read (i.e. decode_custom_tlv returns true),
 468                                                         // continue to the next TLV read.
 469                                                         s.eat_remaining()?;
 470                                                         continue 'tlv_read;
 471                                                 }
 472                                         )?
 473                                         if t % 2 == 0 {
 474                                                 return Err(DecodeError::UnknownRequiredFeature);
 475                                         }
 476                                 }
 477                         }
 478                         s.eat_remaining()?;
 479                 }
 480                 // Make sure we got to each required type after we've read every TLV:
 481                 $({
 482                         $crate::_check_missing_tlv!(last_seen_type, $type, $field, $fieldty);
 483                 })*
 484         } }
 485 }
 486
 487 /// Implements [`Readable`]/[`Writeable`] for a message struct that may include non-TLV and
 488 /// TLV-encoded parts.
 489 ///
 490 /// This is useful to implement a [`CustomMessageReader`].
 491 ///
 492 /// Currently `$fieldty` may only be `option`, i.e., `$tlvfield` is optional field.
 493 ///
 494 /// For example,
 495 /// ```
 496 /// # use lightning::impl_writeable_msg;
 497 /// struct MyCustomMessage {
 498 ///     pub field_1: u32,
 499 ///     pub field_2: bool,
 500 ///     pub field_3: String,
 501 ///     pub tlv_optional_integer: Option<u32>,
 502 /// }
 503 ///
 504 /// impl_writeable_msg!(MyCustomMessage, {
 505 ///     field_1,
 506 ///     field_2,
 507 ///     field_3
 508 /// }, {
 509 ///     (1, tlv_optional_integer, option),
 510 /// });
 511 /// ```
 512 ///
 513 /// [`Readable`]: crate::util::ser::Readable
 514 /// [`Writeable`]: crate::util::ser::Writeable
 515 /// [`CustomMessageReader`]: crate::ln::wire::CustomMessageReader
 516 #[macro_export]
 517 macro_rules! impl_writeable_msg {
 518         ($st:ident, {$($field:ident),* $(,)*}, {$(($type: expr, $tlvfield: ident, $fieldty: tt)),* $(,)*}) => {
 519                 impl $crate::util::ser::Writeable for $st {
 520                         fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
 521                                 $( self.$field.write(w)?; )*
 522                                 $crate::encode_tlv_stream!(w, {$(($type, self.$tlvfield, $fieldty)),*});
 523                                 Ok(())
 524                         }
 525                 }
 526                 impl $crate::util::ser::Readable for $st {
 527                         fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 528                                 $(let $field = $crate::util::ser::Readable::read(r)?;)*
 529                                 $($crate::_init_tlv_field_var!($tlvfield, $fieldty);)*
 530                                 $crate::decode_tlv_stream!(r, {$(($type, $tlvfield, $fieldty)),*});
 531                                 Ok(Self {
 532                                         $($field),*,
 533                                         $($tlvfield),*
 534                                 })
 535                         }
 536                 }
 537         }
 538 }
 539
 540 macro_rules! impl_writeable {
 541         ($st:ident, {$($field:ident),*}) => {
 542                 impl $crate::util::ser::Writeable for $st {
 543                         fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
 544                                 $( self.$field.write(w)?; )*
 545                                 Ok(())
 546                         }
 547
 548                         #[inline]
 549                         fn serialized_length(&self) -> usize {
 550                                 let mut len_calc = 0;
 551                                 $( len_calc += self.$field.serialized_length(); )*
 552                                 return len_calc;
 553                         }
 554                 }
 555
 556                 impl $crate::util::ser::Readable for $st {
 557                         fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 558                                 Ok(Self {
 559                                         $($field: $crate::util::ser::Readable::read(r)?),*
 560                                 })
 561                         }
 562                 }
 563         }
 564 }
 565
 566 /// Write out two bytes to indicate the version of an object.
 567 ///
 568 /// $this_version represents a unique version of a type. Incremented whenever the type's
 569 /// serialization format has changed or has a new interpretation. Used by a type's reader to
 570 /// determine how to interpret fields or if it can understand a serialized object.
 571 ///
 572 /// $min_version_that_can_read_this is the minimum reader version which can understand this
 573 /// serialized object. Previous versions will simply err with a [`DecodeError::UnknownVersion`].
 574 ///
 575 /// Updates to either `$this_version` or `$min_version_that_can_read_this` should be included in
 576 /// release notes.
 577 ///
 578 /// Both version fields can be specific to this type of object.
 579 ///
 580 /// [`DecodeError::UnknownVersion`]: crate::ln::msgs::DecodeError::UnknownVersion
 581 macro_rules! write_ver_prefix {
 582         ($stream: expr, $this_version: expr, $min_version_that_can_read_this: expr) => {
 583                 $stream.write_all(&[$this_version; 1])?;
 584                 $stream.write_all(&[$min_version_that_can_read_this; 1])?;
 585         }
 586 }
 587
 588 /// Writes out a suffix to an object as a length-prefixed TLV stream which contains potentially
 589 /// backwards-compatible, optional fields which old nodes can happily ignore.
 590 ///
 591 /// It is written out in TLV format and, as with all TLV fields, unknown even fields cause a
 592 /// [`DecodeError::UnknownRequiredFeature`] error, with unknown odd fields ignored.
 593 ///
 594 /// This is the preferred method of adding new fields that old nodes can ignore and still function
 595 /// correctly.
 596 ///
 597 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
 598 #[macro_export]
 599 macro_rules! write_tlv_fields {
 600         ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => {
 601                 $crate::_encode_varint_length_prefixed_tlv!($stream, {$(($type, $field, $fieldty)),*})
 602         }
 603 }
 604
 605 /// Reads a prefix added by [`write_ver_prefix`], above. Takes the current version of the
 606 /// serialization logic for this object. This is compared against the
 607 /// `$min_version_that_can_read_this` added by [`write_ver_prefix`].
 608 macro_rules! read_ver_prefix {
 609         ($stream: expr, $this_version: expr) => { {
 610                 let ver: u8 = Readable::read($stream)?;
 611                 let min_ver: u8 = Readable::read($stream)?;
 612                 if min_ver > $this_version {
 613                         return Err(DecodeError::UnknownVersion);
 614                 }
 615                 ver
 616         } }
 617 }
 618
 619 /// Reads a suffix added by [`write_tlv_fields`].
 620 ///
 621 /// [`write_tlv_fields`]: crate::write_tlv_fields
 622 #[macro_export]
 623 macro_rules! read_tlv_fields {
 624         ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => { {
 625                 let tlv_len: $crate::util::ser::BigSize = $crate::util::ser::Readable::read($stream)?;
 626                 let mut rd = $crate::util::ser::FixedLengthReader::new($stream, tlv_len.0);
 627                 $crate::decode_tlv_stream!(&mut rd, {$(($type, $field, $fieldty)),*});
 628                 rd.eat_remaining().map_err(|_| $crate::ln::msgs::DecodeError::ShortRead)?;
 629         } }
 630 }
 631
 632 /// Initializes the struct fields.
 633 ///
 634 /// This is exported for use by other exported macros, do not use directly.
 635 #[doc(hidden)]
 636 #[macro_export]
 637 macro_rules! _init_tlv_based_struct_field {
 638         ($field: ident, (default_value, $default: expr)) => {
 639                 $field.0.unwrap()
 640         };
 641         ($field: ident, (static_value, $value: expr)) => {
 642                 $field
 643         };
 644         ($field: ident, option) => {
 645                 $field
 646         };
 647         ($field: ident, upgradable_required) => {
 648                 $field.0.unwrap()
 649         };
 650         ($field: ident, upgradable_option) => {
 651                 $field
 652         };
 653         ($field: ident, required) => {
 654                 $field.0.unwrap()
 655         };
 656         ($field: ident, vec_type) => {
 657                 $field.unwrap()
 658         };
 659 }
 660
 661 /// Initializes the variable we are going to read the TLV into.
 662 ///
 663 /// This is exported for use by other exported macros, do not use directly.
 664 #[doc(hidden)]
 665 #[macro_export]
 666 macro_rules! _init_tlv_field_var {
 667         ($field: ident, (default_value, $default: expr)) => {
 668                 let mut $field = $crate::util::ser::RequiredWrapper(None);
 669         };
 670         ($field: ident, (static_value, $value: expr)) => {
 671                 let $field;
 672         };
 673         ($field: ident, required) => {
 674                 let mut $field = $crate::util::ser::RequiredWrapper(None);
 675         };
 676         ($field: ident, vec_type) => {
 677                 let mut $field = Some(Vec::new());
 678         };
 679         ($field: ident, option) => {
 680                 let mut $field = None;
 681         };
 682         ($field: ident, upgradable_required) => {
 683                 let mut $field = $crate::util::ser::UpgradableRequired(None);
 684         };
 685         ($field: ident, upgradable_option) => {
 686                 let mut $field = None;
 687         };
 688 }
 689
 690 /// Equivalent to running [`_init_tlv_field_var`] then [`read_tlv_fields`].
 691 ///
 692 /// This is exported for use by other exported macros, do not use directly.
 693 #[doc(hidden)]
 694 #[macro_export]
 695 macro_rules! _init_and_read_tlv_fields {
 696         ($reader: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
 697                 $(
 698                         $crate::_init_tlv_field_var!($field, $fieldty);
 699                 )*
 700
 701                 $crate::read_tlv_fields!($reader, {
 702                         $(($type, $field, $fieldty)),*
 703                 });
 704         }
 705 }
 706
 707 /// Implements [`Readable`]/[`Writeable`] for a struct storing it as a set of TLVs
 708 /// If `$fieldty` is `required`, then `$field` is a required field that is not an [`Option`] nor a [`Vec`].
 709 /// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
 710 /// If `$fieldty` is `option`, then `$field` is optional field.
 711 /// If `$fieldty` is `vec_type`, then `$field` is a [`Vec`], which needs to have its individual elements serialized.
 712 ///
 713 /// For example,
 714 /// ```
 715 /// # use lightning::impl_writeable_tlv_based;
 716 /// struct LightningMessage {
 717 ///     tlv_integer: u32,
 718 ///     tlv_default_integer: u32,
 719 ///     tlv_optional_integer: Option<u32>,
 720 ///     tlv_vec_type_integer: Vec<u32>,
 721 /// }
 722 ///
 723 /// impl_writeable_tlv_based!(LightningMessage, {
 724 ///     (0, tlv_integer, required),
 725 ///     (1, tlv_default_integer, (default_value, 7)),
 726 ///     (2, tlv_optional_integer, option),
 727 ///     (3, tlv_vec_type_integer, vec_type),
 728 /// });
 729 /// ```
 730 ///
 731 /// [`Readable`]: crate::util::ser::Readable
 732 /// [`Writeable`]: crate::util::ser::Writeable
 733 #[macro_export]
 734 macro_rules! impl_writeable_tlv_based {
 735         ($st: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
 736                 impl $crate::util::ser::Writeable for $st {
 737                         fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
 738                                 $crate::write_tlv_fields!(writer, {
 739                                         $(($type, self.$field, $fieldty)),*
 740                                 });
 741                                 Ok(())
 742                         }
 743
 744                         #[inline]
 745                         fn serialized_length(&self) -> usize {
 746                                 use $crate::util::ser::BigSize;
 747                                 let len = {
 748                                         #[allow(unused_mut)]
 749                                         let mut len = $crate::util::ser::LengthCalculatingWriter(0);
 750                                         $(
 751                                                 $crate::_get_varint_length_prefixed_tlv_length!(len, $type, self.$field, $fieldty);
 752                                         )*
 753                                         len.0
 754                                 };
 755                                 let mut len_calc = $crate::util::ser::LengthCalculatingWriter(0);
 756                                 BigSize(len as u64).write(&mut len_calc).expect("No in-memory data may fail to serialize");
 757                                 len + len_calc.0
 758                         }
 759                 }
 760
 761                 impl $crate::util::ser::Readable for $st {
 762                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 763                                 $crate::_init_and_read_tlv_fields!(reader, {
 764                                         $(($type, $field, $fieldty)),*
 765                                 });
 766                                 Ok(Self {
 767                                         $(
 768                                                 $field: $crate::_init_tlv_based_struct_field!($field, $fieldty)
 769                                         ),*
 770                                 })
 771                         }
 772                 }
 773         }
 774 }
 775
 776 /// Defines a struct for a TLV stream and a similar struct using references for non-primitive types,
 777 /// implementing [`Readable`] for the former and [`Writeable`] for the latter. Useful as an
 778 /// intermediary format when reading or writing a type encoded as a TLV stream. Note that each field
 779 /// representing a TLV record has its type wrapped with an [`Option`]. A tuple consisting of a type
 780 /// and a serialization wrapper may be given in place of a type when custom serialization is
 781 /// required.
 782 ///
 783 /// [`Readable`]: crate::util::ser::Readable
 784 /// [`Writeable`]: crate::util::ser::Writeable
 785 macro_rules! tlv_stream {
 786         ($name:ident, $nameref:ident, $range:expr, {
 787                 $(($type:expr, $field:ident : $fieldty:tt)),* $(,)*
 788         }) => {
 789                 #[derive(Debug)]
 790                 pub(super) struct $name {
 791                         $(
 792                                 pub(super) $field: Option<tlv_record_type!($fieldty)>,
 793                         )*
 794                 }
 795
 796                 #[cfg_attr(test, derive(PartialEq))]
 797                 #[derive(Debug)]
 798                 pub(super) struct $nameref<'a> {
 799                         $(
 800                                 pub(super) $field: Option<tlv_record_ref_type!($fieldty)>,
 801                         )*
 802                 }
 803
 804                 impl<'a> $crate::util::ser::Writeable for $nameref<'a> {
 805                         fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
 806                                 encode_tlv_stream!(writer, {
 807                                         $(($type, self.$field, (option, encoding: $fieldty))),*
 808                                 });
 809                                 Ok(())
 810                         }
 811                 }
 812
 813                 impl $crate::util::ser::SeekReadable for $name {
 814                         fn read<R: $crate::io::Read + $crate::io::Seek>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 815                                 $(
 816                                         _init_tlv_field_var!($field, option);
 817                                 )*
 818                                 let rewind = |cursor: &mut R, offset: usize| {
 819                                         cursor.seek($crate::io::SeekFrom::Current(-(offset as i64))).expect("");
 820                                 };
 821                                 _decode_tlv_stream_range!(reader, $range, rewind, {
 822                                         $(($type, $field, (option, encoding: $fieldty))),*
 823                                 });
 824
 825                                 Ok(Self {
 826                                         $(
 827                                                 $field: $field
 828                                         ),*
 829                                 })
 830                         }
 831                 }
 832         }
 833 }
 834
 835 macro_rules! tlv_record_type {
 836         (($type:ty, $wrapper:ident)) => { $type };
 837         (($type:ty, $wrapper:ident, $encoder:ty)) => { $type };
 838         ($type:ty) => { $type };
 839 }
 840
 841 macro_rules! tlv_record_ref_type {
 842         (char) => { char };
 843         (u8) => { u8 };
 844         ((u16, $wrapper: ident)) => { u16 };
 845         ((u32, $wrapper: ident)) => { u32 };
 846         ((u64, $wrapper: ident)) => { u64 };
 847         (($type:ty, $wrapper:ident)) => { &'a $type };
 848         (($type:ty, $wrapper:ident, $encoder:ty)) => { $encoder };
 849         ($type:ty) => { &'a $type };
 850 }
 851
 852 macro_rules! _impl_writeable_tlv_based_enum_common {
 853         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
 854                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 855         ),* $(,)*;
 856         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*) => {
 857                 impl $crate::util::ser::Writeable for $st {
 858                         fn write<W: $crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
 859                                 match self {
 860                                         $($st::$variant_name { $(ref $field),* } => {
 861                                                 let id: u8 = $variant_id;
 862                                                 id.write(writer)?;
 863                                                 write_tlv_fields!(writer, {
 864                                                         $(($type, *$field, $fieldty)),*
 865                                                 });
 866                                         }),*
 867                                         $($st::$tuple_variant_name (ref field) => {
 868                                                 let id: u8 = $tuple_variant_id;
 869                                                 id.write(writer)?;
 870                                                 field.write(writer)?;
 871                                         }),*
 872                                 }
 873                                 Ok(())
 874                         }
 875                 }
 876         }
 877 }
 878
 879 /// Implement [`Readable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and tuple
 880 /// variants stored directly.
 881 /// The format is, for example
 882 /// ```ignore
 883 /// impl_writeable_tlv_based_enum!(EnumName,
 884 ///   (0, StructVariantA) => {(0, required_variant_field, required), (1, optional_variant_field, option)},
 885 ///   (1, StructVariantB) => {(0, variant_field_a, required), (1, variant_field_b, required), (2, variant_vec_field, vec_type)};
 886 ///   (2, TupleVariantA), (3, TupleVariantB),
 887 /// );
 888 /// ```
 889 /// The type is written as a single byte, followed by any variant data.
 890 /// Attempts to read an unknown type byte result in [`DecodeError::UnknownRequiredFeature`].
 891 ///
 892 /// [`Readable`]: crate::util::ser::Readable
 893 /// [`Writeable`]: crate::util::ser::Writeable
 894 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
 895 #[macro_export]
 896 macro_rules! impl_writeable_tlv_based_enum {
 897         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
 898                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 899         ),* $(,)*;
 900         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*) => {
 901                 _impl_writeable_tlv_based_enum_common!($st,
 902                         $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
 903                         $(($tuple_variant_id, $tuple_variant_name)),*);
 904
 905                 impl $crate::util::ser::Readable for $st {
 906                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
 907                                 let id: u8 = $crate::util::ser::Readable::read(reader)?;
 908                                 match id {
 909                                         $($variant_id => {
 910                                                 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
 911                                                 // in the same function body. Instead, we define a closure and call it.
 912                                                 let f = || {
 913                                                         _init_and_read_tlv_fields!(reader, {
 914                                                                 $(($type, $field, $fieldty)),*
 915                                                         });
 916                                                         Ok($st::$variant_name {
 917                                                                 $(
 918                                                                         $field: _init_tlv_based_struct_field!($field, $fieldty)
 919                                                                 ),*
 920                                                         })
 921                                                 };
 922                                                 f()
 923                                         }),*
 924                                         $($tuple_variant_id => {
 925                                                 Ok($st::$tuple_variant_name(Readable::read(reader)?))
 926                                         }),*
 927                                         _ => {
 928                                                 Err($crate::ln::msgs::DecodeError::UnknownRequiredFeature)
 929                                         },
 930                                 }
 931                         }
 932                 }
 933         }
 934 }
 935
 936 /// Implement [`MaybeReadable`] and [`Writeable`] for an enum, with struct variants stored as TLVs and
 937 /// tuple variants stored directly.
 938 ///
 939 /// This is largely identical to [`impl_writeable_tlv_based_enum`], except that odd variants will
 940 /// return `Ok(None)` instead of `Err(`[`DecodeError::UnknownRequiredFeature`]`)`. It should generally be preferred
 941 /// when [`MaybeReadable`] is practical instead of just [`Readable`] as it provides an upgrade path for
 942 /// new variants to be added which are simply ignored by existing clients.
 943 ///
 944 /// [`MaybeReadable`]: crate::util::ser::MaybeReadable
 945 /// [`Writeable`]: crate::util::ser::Writeable
 946 /// [`DecodeError::UnknownRequiredFeature`]: crate::ln::msgs::DecodeError::UnknownRequiredFeature
 947 /// [`Readable`]: crate::util::ser::Readable
 948 #[macro_export]
 949 macro_rules! impl_writeable_tlv_based_enum_upgradable {
 950         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
 951                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 952         ),* $(,)*
 953         $(;
 954         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*)*) => {
 955                 _impl_writeable_tlv_based_enum_common!($st,
 956                         $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
 957                         $($(($tuple_variant_id, $tuple_variant_name)),*)*);
 958
 959                 impl $crate::util::ser::MaybeReadable for $st {
 960                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Option<Self>, $crate::ln::msgs::DecodeError> {
 961                                 let id: u8 = $crate::util::ser::Readable::read(reader)?;
 962                                 match id {
 963                                         $($variant_id => {
 964                                                 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
 965                                                 // in the same function body. Instead, we define a closure and call it.
 966                                                 let f = || {
 967                                                         _init_and_read_tlv_fields!(reader, {
 968                                                                 $(($type, $field, $fieldty)),*
 969                                                         });
 970                                                         Ok(Some($st::$variant_name {
 971                                                                 $(
 972                                                                         $field: _init_tlv_based_struct_field!($field, $fieldty)
 973                                                                 ),*
 974                                                         }))
 975                                                 };
 976                                                 f()
 977                                         }),*
 978                                         $($($tuple_variant_id => {
 979                                                 Ok(Some($st::$tuple_variant_name(Readable::read(reader)?)))
 980                                         }),*)*
 981                                         _ if id % 2 == 1 => Ok(None),
 982                                         _ => Err($crate::ln::msgs::DecodeError::UnknownRequiredFeature),
 983                                 }
 984                         }
 985                 }
 986         }
 987 }
 988
 989 #[cfg(test)]
 990 mod tests {
 991         use crate::io::{self, Cursor};
 992         use crate::prelude::*;
 993         use crate::ln::msgs::DecodeError;
 994         use crate::util::ser::{Writeable, HighZeroBytesDroppedBigSize, VecWriter};
 995         use bitcoin::secp256k1::PublicKey;
 996
 997         // The BOLT TLV test cases don't include any tests which use our "required-value" logic since
 998         // the encoding layer in the BOLTs has no such concept, though it makes our macros easier to
 999         // work with so they're baked into the decoder. Thus, we have a few additional tests below
1000         fn tlv_reader(s: &[u8]) -> Result<(u64, u32, Option<u32>), DecodeError> {
1001                 let mut s = Cursor::new(s);
1002                 let mut a: u64 = 0;
1003                 let mut b: u32 = 0;
1004                 let mut c: Option<u32> = None;
1005                 decode_tlv_stream!(&mut s, {(2, a, required), (3, b, required), (4, c, option)});
1006                 Ok((a, b, c))
1007         }
1008
1009         #[test]
1010         fn tlv_v_short_read() {
1011                 // We only expect a u32 for type 3 (which we are given), but the L says its 8 bytes.
1012                 if let Err(DecodeError::ShortRead) = tlv_reader(&::hex::decode(
1013                                 concat!("0100", "0208deadbeef1badbeef", "0308deadbeef")
1014                                 ).unwrap()[..]) {
1015                 } else { panic!(); }
1016         }
1017
1018         #[test]
1019         fn tlv_types_out_of_order() {
1020                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
1021                                 concat!("0100", "0304deadbeef", "0208deadbeef1badbeef")
1022                                 ).unwrap()[..]) {
1023                 } else { panic!(); }
1024                 // ...even if its some field we don't understand
1025                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
1026                                 concat!("0208deadbeef1badbeef", "0100", "0304deadbeef")
1027                                 ).unwrap()[..]) {
1028                 } else { panic!(); }
1029         }
1030
1031         #[test]
1032         fn tlv_req_type_missing_or_extra() {
1033                 // It's also bad if they included even fields we don't understand
1034                 if let Err(DecodeError::UnknownRequiredFeature) = tlv_reader(&::hex::decode(
1035                                 concat!("0100", "0208deadbeef1badbeef", "0304deadbeef", "0600")
1036                                 ).unwrap()[..]) {
1037                 } else { panic!(); }
1038                 // ... or if they're missing fields we need
1039                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
1040                                 concat!("0100", "0208deadbeef1badbeef")
1041                                 ).unwrap()[..]) {
1042                 } else { panic!(); }
1043                 // ... even if that field is even
1044                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
1045                                 concat!("0304deadbeef", "0500")
1046                                 ).unwrap()[..]) {
1047                 } else { panic!(); }
1048         }
1049
1050         #[test]
1051         fn tlv_simple_good_cases() {
1052                 assert_eq!(tlv_reader(&::hex::decode(
1053                                 concat!("0208deadbeef1badbeef", "03041bad1dea")
1054                                 ).unwrap()[..]).unwrap(),
1055                         (0xdeadbeef1badbeef, 0x1bad1dea, None));
1056                 assert_eq!(tlv_reader(&::hex::decode(
1057                                 concat!("0208deadbeef1badbeef", "03041bad1dea", "040401020304")
1058                                 ).unwrap()[..]).unwrap(),
1059                         (0xdeadbeef1badbeef, 0x1bad1dea, Some(0x01020304)));
1060         }
1061
1062         #[derive(Debug, PartialEq)]
1063         struct TestUpgradable {
1064                 a: u32,
1065                 b: u32,
1066                 c: Option<u32>,
1067         }
1068
1069         fn upgradable_tlv_reader(s: &[u8]) -> Result<Option<TestUpgradable>, DecodeError> {
1070                 let mut s = Cursor::new(s);
1071                 let mut a = 0;
1072                 let mut b = 0;
1073                 let mut c: Option<u32> = None;
1074                 decode_tlv_stream!(&mut s, {(2, a, upgradable_required), (3, b, upgradable_required), (4, c, upgradable_option)});
1075                 Ok(Some(TestUpgradable { a, b, c, }))
1076         }
1077
1078         #[test]
1079         fn upgradable_tlv_simple_good_cases() {
1080                 assert_eq!(upgradable_tlv_reader(&::hex::decode(
1081                         concat!("0204deadbeef", "03041bad1dea", "0404deadbeef")
1082                 ).unwrap()[..]).unwrap(),
1083                 Some(TestUpgradable { a: 0xdeadbeef, b: 0x1bad1dea, c: Some(0xdeadbeef) }));
1084
1085                 assert_eq!(upgradable_tlv_reader(&::hex::decode(
1086                         concat!("0204deadbeef", "03041bad1dea")
1087                 ).unwrap()[..]).unwrap(),
1088                 Some(TestUpgradable { a: 0xdeadbeef, b: 0x1bad1dea, c: None}));
1089         }
1090
1091         #[test]
1092         fn missing_required_upgradable() {
1093                 if let Err(DecodeError::InvalidValue) = upgradable_tlv_reader(&::hex::decode(
1094                         concat!("0100", "0204deadbeef")
1095                         ).unwrap()[..]) {
1096                 } else { panic!(); }
1097                 if let Err(DecodeError::InvalidValue) = upgradable_tlv_reader(&::hex::decode(
1098                         concat!("0100", "03041bad1dea")
1099                 ).unwrap()[..]) {
1100                 } else { panic!(); }
1101         }
1102
1103         // BOLT TLV test cases
1104         fn tlv_reader_n1(s: &[u8]) -> Result<(Option<HighZeroBytesDroppedBigSize<u64>>, Option<u64>, Option<(PublicKey, u64, u64)>, Option<u16>), DecodeError> {
1105                 let mut s = Cursor::new(s);
1106                 let mut tlv1: Option<HighZeroBytesDroppedBigSize<u64>> = None;
1107                 let mut tlv2: Option<u64> = None;
1108                 let mut tlv3: Option<(PublicKey, u64, u64)> = None;
1109                 let mut tlv4: Option<u16> = None;
1110                 decode_tlv_stream!(&mut s, {(1, tlv1, option), (2, tlv2, option), (3, tlv3, option), (254, tlv4, option)});
1111                 Ok((tlv1, tlv2, tlv3, tlv4))
1112         }
1113
1114         #[test]
1115         fn bolt_tlv_bogus_stream() {
1116                 macro_rules! do_test {
1117                         ($stream: expr, $reason: ident) => {
1118                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1119                                 } else { panic!(); }
1120                         }
1121                 }
1122
1123                 // TLVs from the BOLT test cases which should not decode as either n1 or n2
1124                 do_test!(concat!("fd01"), ShortRead);
1125                 do_test!(concat!("fd0001", "00"), InvalidValue);
1126                 do_test!(concat!("fd0101"), ShortRead);
1127                 do_test!(concat!("0f", "fd"), ShortRead);
1128                 do_test!(concat!("0f", "fd26"), ShortRead);
1129                 do_test!(concat!("0f", "fd2602"), ShortRead);
1130                 do_test!(concat!("0f", "fd0001", "00"), InvalidValue);
1131                 do_test!(concat!("0f", "fd0201", "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), ShortRead);
1132
1133                 do_test!(concat!("12", "00"), UnknownRequiredFeature);
1134                 do_test!(concat!("fd0102", "00"), UnknownRequiredFeature);
1135                 do_test!(concat!("fe01000002", "00"), UnknownRequiredFeature);
1136                 do_test!(concat!("ff0100000000000002", "00"), UnknownRequiredFeature);
1137         }
1138
1139         #[test]
1140         fn bolt_tlv_bogus_n1_stream() {
1141                 macro_rules! do_test {
1142                         ($stream: expr, $reason: ident) => {
1143                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1144                                 } else { panic!(); }
1145                         }
1146                 }
1147
1148                 // TLVs from the BOLT test cases which should not decode as n1
1149                 do_test!(concat!("01", "09", "ffffffffffffffffff"), InvalidValue);
1150                 do_test!(concat!("01", "01", "00"), InvalidValue);
1151                 do_test!(concat!("01", "02", "0001"), InvalidValue);
1152                 do_test!(concat!("01", "03", "000100"), InvalidValue);
1153                 do_test!(concat!("01", "04", "00010000"), InvalidValue);
1154                 do_test!(concat!("01", "05", "0001000000"), InvalidValue);
1155                 do_test!(concat!("01", "06", "000100000000"), InvalidValue);
1156                 do_test!(concat!("01", "07", "00010000000000"), InvalidValue);
1157                 do_test!(concat!("01", "08", "0001000000000000"), InvalidValue);
1158                 do_test!(concat!("02", "07", "01010101010101"), ShortRead);
1159                 do_test!(concat!("02", "09", "010101010101010101"), InvalidValue);
1160                 do_test!(concat!("03", "21", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb"), ShortRead);
1161                 do_test!(concat!("03", "29", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001"), ShortRead);
1162                 do_test!(concat!("03", "30", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb000000000000000100000000000001"), ShortRead);
1163                 do_test!(concat!("03", "31", "043da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"), InvalidValue);
1164                 do_test!(concat!("03", "32", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001000000000000000001"), InvalidValue);
1165                 do_test!(concat!("fd00fe", "00"), ShortRead);
1166                 do_test!(concat!("fd00fe", "01", "01"), ShortRead);
1167                 do_test!(concat!("fd00fe", "03", "010101"), InvalidValue);
1168                 do_test!(concat!("00", "00"), UnknownRequiredFeature);
1169
1170                 do_test!(concat!("02", "08", "0000000000000226", "01", "01", "2a"), InvalidValue);
1171                 do_test!(concat!("02", "08", "0000000000000231", "02", "08", "0000000000000451"), InvalidValue);
1172                 do_test!(concat!("1f", "00", "0f", "01", "2a"), InvalidValue);
1173                 do_test!(concat!("1f", "00", "1f", "01", "2a"), InvalidValue);
1174
1175                 // The last BOLT test modified to not require creating a new decoder for one trivial test.
1176                 do_test!(concat!("ffffffffffffffffff", "00", "01", "00"), InvalidValue);
1177         }
1178
1179         #[test]
1180         fn bolt_tlv_valid_n1_stream() {
1181                 macro_rules! do_test {
1182                         ($stream: expr, $tlv1: expr, $tlv2: expr, $tlv3: expr, $tlv4: expr) => {
1183                                 if let Ok((tlv1, tlv2, tlv3, tlv4)) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
1184                                         assert_eq!(tlv1.map(|v| v.0), $tlv1);
1185                                         assert_eq!(tlv2, $tlv2);
1186                                         assert_eq!(tlv3, $tlv3);
1187                                         assert_eq!(tlv4, $tlv4);
1188                                 } else { panic!(); }
1189                         }
1190                 }
1191
1192                 do_test!(concat!(""), None, None, None, None);
1193                 do_test!(concat!("21", "00"), None, None, None, None);
1194                 do_test!(concat!("fd0201", "00"), None, None, None, None);
1195                 do_test!(concat!("fd00fd", "00"), None, None, None, None);
1196                 do_test!(concat!("fd00ff", "00"), None, None, None, None);
1197                 do_test!(concat!("fe02000001", "00"), None, None, None, None);
1198                 do_test!(concat!("ff0200000000000001", "00"), None, None, None, None);
1199
1200                 do_test!(concat!("01", "00"), Some(0), None, None, None);
1201                 do_test!(concat!("01", "01", "01"), Some(1), None, None, None);
1202                 do_test!(concat!("01", "02", "0100"), Some(256), None, None, None);
1203                 do_test!(concat!("01", "03", "010000"), Some(65536), None, None, None);
1204                 do_test!(concat!("01", "04", "01000000"), Some(16777216), None, None, None);
1205                 do_test!(concat!("01", "05", "0100000000"), Some(4294967296), None, None, None);
1206                 do_test!(concat!("01", "06", "010000000000"), Some(1099511627776), None, None, None);
1207                 do_test!(concat!("01", "07", "01000000000000"), Some(281474976710656), None, None, None);
1208                 do_test!(concat!("01", "08", "0100000000000000"), Some(72057594037927936), None, None, None);
1209                 do_test!(concat!("02", "08", "0000000000000226"), None, Some((0 << 30) | (0 << 5) | (550 << 0)), None, None);
1210                 do_test!(concat!("03", "31", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"),
1211                         None, None, Some((
1212                                 PublicKey::from_slice(&::hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]).unwrap(), 1, 2)),
1213                         None);
1214                 do_test!(concat!("fd00fe", "02", "0226"), None, None, None, Some(550));
1215         }
1216
1217         fn do_simple_test_tlv_write() -> Result<(), io::Error> {
1218                 let mut stream = VecWriter(Vec::new());
1219
1220                 stream.0.clear();
1221                 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, 1u8, required), (42, None::<u64>, option)});
1222                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1223
1224                 stream.0.clear();
1225                 _encode_varint_length_prefixed_tlv!(&mut stream, {(1, Some(1u8), option)});
1226                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
1227
1228                 stream.0.clear();
1229                 _encode_varint_length_prefixed_tlv!(&mut stream, {(4, 0xabcdu16, required), (42, None::<u64>, option)});
1230                 assert_eq!(stream.0, ::hex::decode("040402abcd").unwrap());
1231
1232                 stream.0.clear();
1233                 _encode_varint_length_prefixed_tlv!(&mut stream, {(42, None::<u64>, option), (0xff, 0xabcdu16, required)});
1234                 assert_eq!(stream.0, ::hex::decode("06fd00ff02abcd").unwrap());
1235
1236                 stream.0.clear();
1237                 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, 1u64, required), (42, None::<u64>, option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1238                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1239
1240                 stream.0.clear();
1241                 _encode_varint_length_prefixed_tlv!(&mut stream, {(0, Some(1u64), option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
1242                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
1243
1244                 Ok(())
1245         }
1246
1247         #[test]
1248         fn simple_test_tlv_write() {
1249                 do_simple_test_tlv_write().unwrap();
1250         }
1251 }