_ 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 macro_rules! encode_tlv {
  11         ($stream: expr, $type: expr, $field: expr, (default_value, $default: expr)) => {
  12                 encode_tlv!($stream, $type, $field, required)
  13         };
  14         ($stream: expr, $type: expr, $field: expr, required) => {
  15                 BigSize($type).write($stream)?;
  16                 BigSize($field.serialized_length() as u64).write($stream)?;
  17                 $field.write($stream)?;
  18         };
  19         ($stream: expr, $type: expr, $field: expr, vec_type) => {
  20                 encode_tlv!($stream, $type, ::util::ser::VecWriteWrapper(&$field), required);
  21         };
  22         ($stream: expr, $optional_type: expr, $optional_field: expr, option) => {
  23                 if let Some(ref field) = $optional_field {
  24                         BigSize($optional_type).write($stream)?;
  25                         BigSize(field.serialized_length() as u64).write($stream)?;
  26                         field.write($stream)?;
  27                 }
  28         };
  29 }
  30
  31 macro_rules! encode_tlv_stream {
  32         ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => { {
  33                 #[allow(unused_imports)]
  34                 use {
  35                         ln::msgs::DecodeError,
  36                         util::ser,
  37                         util::ser::BigSize,
  38                 };
  39
  40                 $(
  41                         encode_tlv!($stream, $type, $field, $fieldty);
  42                 )*
  43
  44                 #[allow(unused_mut, unused_variables, unused_assignments)]
  45                 #[cfg(debug_assertions)]
  46                 {
  47                         let mut last_seen: Option<u64> = None;
  48                         $(
  49                                 if let Some(t) = last_seen {
  50                                         debug_assert!(t <= $type);
  51                                 }
  52                                 last_seen = Some($type);
  53                         )*
  54                 }
  55         } }
  56 }
  57
  58 macro_rules! get_varint_length_prefixed_tlv_length {
  59         ($len: expr, $type: expr, $field: expr, (default_value, $default: expr)) => {
  60                 get_varint_length_prefixed_tlv_length!($len, $type, $field, required)
  61         };
  62         ($len: expr, $type: expr, $field: expr, required) => {
  63                 BigSize($type).write(&mut $len).expect("No in-memory data may fail to serialize");
  64                 let field_len = $field.serialized_length();
  65                 BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
  66                 $len.0 += field_len;
  67         };
  68         ($len: expr, $type: expr, $field: expr, vec_type) => {
  69                 get_varint_length_prefixed_tlv_length!($len, $type, ::util::ser::VecWriteWrapper(&$field), required);
  70         };
  71         ($len: expr, $optional_type: expr, $optional_field: expr, option) => {
  72                 if let Some(ref field) = $optional_field {
  73                         BigSize($optional_type).write(&mut $len).expect("No in-memory data may fail to serialize");
  74                         let field_len = field.serialized_length();
  75                         BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
  76                         $len.0 += field_len;
  77                 }
  78         };
  79 }
  80
  81 macro_rules! encode_varint_length_prefixed_tlv {
  82         ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),*}) => { {
  83                 use util::ser::BigSize;
  84                 let len = {
  85                         #[allow(unused_mut)]
  86                         let mut len = ::util::ser::LengthCalculatingWriter(0);
  87                         $(
  88                                 get_varint_length_prefixed_tlv_length!(len, $type, $field, $fieldty);
  89                         )*
  90                         len.0
  91                 };
  92                 BigSize(len as u64).write($stream)?;
  93                 encode_tlv_stream!($stream, { $(($type, $field, $fieldty)),* });
  94         } }
  95 }
  96
  97 macro_rules! check_tlv_order {
  98         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (default_value, $default: expr)) => {{
  99                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always true
 100                 let invalid_order = ($last_seen_type.is_none() || $last_seen_type.unwrap() < $type) && $typ.0 > $type;
 101                 if invalid_order {
 102                         $field = $default.into();
 103                 }
 104         }};
 105         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required) => {{
 106                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always true
 107                 let invalid_order = ($last_seen_type.is_none() || $last_seen_type.unwrap() < $type) && $typ.0 > $type;
 108                 if invalid_order {
 109                         return Err(DecodeError::InvalidValue);
 110                 }
 111         }};
 112         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, option) => {{
 113                 // no-op
 114         }};
 115         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, vec_type) => {{
 116                 // no-op
 117         }};
 118         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, ignorable) => {{
 119                 // no-op
 120         }};
 121         ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
 122                 // no-op
 123         }};
 124 }
 125
 126 macro_rules! check_missing_tlv {
 127         ($last_seen_type: expr, $type: expr, $field: ident, (default_value, $default: expr)) => {{
 128                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always true
 129                 let missing_req_type = $last_seen_type.is_none() || $last_seen_type.unwrap() < $type;
 130                 if missing_req_type {
 131                         $field = $default.into();
 132                 }
 133         }};
 134         ($last_seen_type: expr, $type: expr, $field: ident, required) => {{
 135                 #[allow(unused_comparisons)] // Note that $type may be 0 making the second comparison always true
 136                 let missing_req_type = $last_seen_type.is_none() || $last_seen_type.unwrap() < $type;
 137                 if missing_req_type {
 138                         return Err(DecodeError::InvalidValue);
 139                 }
 140         }};
 141         ($last_seen_type: expr, $type: expr, $field: ident, vec_type) => {{
 142                 // no-op
 143         }};
 144         ($last_seen_type: expr, $type: expr, $field: ident, option) => {{
 145                 // no-op
 146         }};
 147         ($last_seen_type: expr, $type: expr, $field: ident, ignorable) => {{
 148                 // no-op
 149         }};
 150         ($last_seen_type: expr, $type: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
 151                 // no-op
 152         }};
 153 }
 154
 155 macro_rules! decode_tlv {
 156         ($reader: expr, $field: ident, (default_value, $default: expr)) => {{
 157                 decode_tlv!($reader, $field, required)
 158         }};
 159         ($reader: expr, $field: ident, required) => {{
 160                 $field = ::util::ser::Readable::read(&mut $reader)?;
 161         }};
 162         ($reader: expr, $field: ident, vec_type) => {{
 163                 let f: ::util::ser::VecReadWrapper<_> = ::util::ser::Readable::read(&mut $reader)?;
 164                 $field = Some(f.0);
 165         }};
 166         ($reader: expr, $field: ident, option) => {{
 167                 $field = Some(::util::ser::Readable::read(&mut $reader)?);
 168         }};
 169         ($reader: expr, $field: ident, ignorable) => {{
 170                 $field = ::util::ser::MaybeReadable::read(&mut $reader)?;
 171         }};
 172         ($reader: expr, $field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {{
 173                 $field = Some($trait::read(&mut $reader $(, $read_arg)*)?);
 174         }};
 175 }
 176
 177 macro_rules! decode_tlv_stream {
 178         ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => { {
 179                 use ln::msgs::DecodeError;
 180                 let mut last_seen_type: Option<u64> = None;
 181                 let mut stream_ref = $stream;
 182                 'tlv_read: loop {
 183                         use util::ser;
 184
 185                         // First decode the type of this TLV:
 186                         let typ: ser::BigSize = {
 187                                 // We track whether any bytes were read during the consensus_decode call to
 188                                 // determine whether we should break or return ShortRead if we get an
 189                                 // UnexpectedEof. This should in every case be largely cosmetic, but its nice to
 190                                 // pass the TLV test vectors exactly, which requre this distinction.
 191                                 let mut tracking_reader = ser::ReadTrackingReader::new(&mut stream_ref);
 192                                 match ser::Readable::read(&mut tracking_reader) {
 193                                         Err(DecodeError::ShortRead) => {
 194                                                 if !tracking_reader.have_read {
 195                                                         break 'tlv_read;
 196                                                 } else {
 197                                                         return Err(DecodeError::ShortRead);
 198                                                 }
 199                                         },
 200                                         Err(e) => return Err(e),
 201                                         Ok(t) => t,
 202                                 }
 203                         };
 204
 205                         // Types must be unique and monotonically increasing:
 206                         match last_seen_type {
 207                                 Some(t) if typ.0 <= t => {
 208                                         return Err(DecodeError::InvalidValue);
 209                                 },
 210                                 _ => {},
 211                         }
 212                         // As we read types, make sure we hit every required type:
 213                         $({
 214                                 check_tlv_order!(last_seen_type, typ, $type, $field, $fieldty);
 215                         })*
 216                         last_seen_type = Some(typ.0);
 217
 218                         // Finally, read the length and value itself:
 219                         let length: ser::BigSize = ser::Readable::read(&mut stream_ref)?;
 220                         let mut s = ser::FixedLengthReader::new(&mut stream_ref, length.0);
 221                         match typ.0 {
 222                                 $($type => {
 223                                         decode_tlv!(s, $field, $fieldty);
 224                                         if s.bytes_remain() {
 225                                                 s.eat_remaining()?; // Return ShortRead if there's actually not enough bytes
 226                                                 return Err(DecodeError::InvalidValue);
 227                                         }
 228                                 },)*
 229                                 x if x % 2 == 0 => {
 230                                         return Err(DecodeError::UnknownRequiredFeature);
 231                                 },
 232                                 _ => {},
 233                         }
 234                         s.eat_remaining()?;
 235                 }
 236                 // Make sure we got to each required type after we've read every TLV:
 237                 $({
 238                         check_missing_tlv!(last_seen_type, $type, $field, $fieldty);
 239                 })*
 240         } }
 241 }
 242
 243 macro_rules! impl_writeable_msg {
 244         ($st:ident, {$($field:ident),* $(,)*}, {$(($type: expr, $tlvfield: ident, $fieldty: tt)),* $(,)*}) => {
 245                 impl ::util::ser::Writeable for $st {
 246                         fn write<W: ::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
 247                                 $( self.$field.write(w)?; )*
 248                                 encode_tlv_stream!(w, {$(($type, self.$tlvfield, $fieldty)),*});
 249                                 Ok(())
 250                         }
 251                 }
 252                 impl ::util::ser::Readable for $st {
 253                         fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, ::ln::msgs::DecodeError> {
 254                                 $(let $field = ::util::ser::Readable::read(r)?;)*
 255                                 $(init_tlv_field_var!($tlvfield, $fieldty);)*
 256                                 decode_tlv_stream!(r, {$(($type, $tlvfield, $fieldty)),*});
 257                                 Ok(Self {
 258                                         $($field),*,
 259                                         $($tlvfield),*
 260                                 })
 261                         }
 262                 }
 263         }
 264 }
 265
 266 macro_rules! impl_writeable {
 267         ($st:ident, {$($field:ident),*}) => {
 268                 impl ::util::ser::Writeable for $st {
 269                         fn write<W: ::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
 270                                 $( self.$field.write(w)?; )*
 271                                 Ok(())
 272                         }
 273
 274                         #[inline]
 275                         fn serialized_length(&self) -> usize {
 276                                 let mut len_calc = 0;
 277                                 $( len_calc += self.$field.serialized_length(); )*
 278                                 return len_calc;
 279                         }
 280                 }
 281
 282                 impl ::util::ser::Readable for $st {
 283                         fn read<R: $crate::io::Read>(r: &mut R) -> Result<Self, ::ln::msgs::DecodeError> {
 284                                 Ok(Self {
 285                                         $($field: ::util::ser::Readable::read(r)?),*
 286                                 })
 287                         }
 288                 }
 289         }
 290 }
 291
 292 /// Write out two bytes to indicate the version of an object.
 293 /// $this_version represents a unique version of a type. Incremented whenever the type's
 294 ///               serialization format has changed or has a new interpretation. Used by a type's
 295 ///               reader to determine how to interpret fields or if it can understand a serialized
 296 ///               object.
 297 /// $min_version_that_can_read_this is the minimum reader version which can understand this
 298 ///                                 serialized object. Previous versions will simply err with a
 299 ///                                 DecodeError::UnknownVersion.
 300 ///
 301 /// Updates to either $this_version or $min_version_that_can_read_this should be included in
 302 /// release notes.
 303 ///
 304 /// Both version fields can be specific to this type of object.
 305 macro_rules! write_ver_prefix {
 306         ($stream: expr, $this_version: expr, $min_version_that_can_read_this: expr) => {
 307                 $stream.write_all(&[$this_version; 1])?;
 308                 $stream.write_all(&[$min_version_that_can_read_this; 1])?;
 309         }
 310 }
 311
 312 /// Writes out a suffix to an object which contains potentially backwards-compatible, optional
 313 /// fields which old nodes can happily ignore.
 314 ///
 315 /// It is written out in TLV format and, as with all TLV fields, unknown even fields cause a
 316 /// DecodeError::UnknownRequiredFeature error, with unknown odd fields ignored.
 317 ///
 318 /// This is the preferred method of adding new fields that old nodes can ignore and still function
 319 /// correctly.
 320 macro_rules! write_tlv_fields {
 321         ($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => {
 322                 encode_varint_length_prefixed_tlv!($stream, {$(($type, $field, $fieldty)),*})
 323         }
 324 }
 325
 326 /// Reads a prefix added by write_ver_prefix!(), above. Takes the current version of the
 327 /// serialization logic for this object. This is compared against the
 328 /// $min_version_that_can_read_this added by write_ver_prefix!().
 329 macro_rules! read_ver_prefix {
 330         ($stream: expr, $this_version: expr) => { {
 331                 let ver: u8 = Readable::read($stream)?;
 332                 let min_ver: u8 = Readable::read($stream)?;
 333                 if min_ver > $this_version {
 334                         return Err(DecodeError::UnknownVersion);
 335                 }
 336                 ver
 337         } }
 338 }
 339
 340 /// Reads a suffix added by write_tlv_fields.
 341 macro_rules! read_tlv_fields {
 342         ($stream: expr, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => { {
 343                 let tlv_len: ::util::ser::BigSize = ::util::ser::Readable::read($stream)?;
 344                 let mut rd = ::util::ser::FixedLengthReader::new($stream, tlv_len.0);
 345                 decode_tlv_stream!(&mut rd, {$(($type, $field, $fieldty)),*});
 346                 rd.eat_remaining().map_err(|_| ::ln::msgs::DecodeError::ShortRead)?;
 347         } }
 348 }
 349
 350 macro_rules! init_tlv_based_struct_field {
 351         ($field: ident, (default_value, $default: expr)) => {
 352                 $field.0.unwrap()
 353         };
 354         ($field: ident, option) => {
 355                 $field
 356         };
 357         ($field: ident, required) => {
 358                 $field.0.unwrap()
 359         };
 360         ($field: ident, vec_type) => {
 361                 $field.unwrap()
 362         };
 363 }
 364
 365 macro_rules! init_tlv_field_var {
 366         ($field: ident, (default_value, $default: expr)) => {
 367                 let mut $field = ::util::ser::OptionDeserWrapper(None);
 368         };
 369         ($field: ident, required) => {
 370                 let mut $field = ::util::ser::OptionDeserWrapper(None);
 371         };
 372         ($field: ident, vec_type) => {
 373                 let mut $field = Some(Vec::new());
 374         };
 375         ($field: ident, option) => {
 376                 let mut $field = None;
 377         };
 378 }
 379
 380 /// Implements Readable/Writeable for a struct storing it as a set of TLVs
 381 /// If $fieldty is `required`, then $field is a required field that is not an Option nor a Vec.
 382 /// If $fieldty is `option`, then $field is optional field.
 383 /// if $fieldty is `vec_type`, then $field is a Vec, which needs to have its individual elements
 384 /// serialized.
 385 macro_rules! impl_writeable_tlv_based {
 386         ($st: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
 387                 impl ::util::ser::Writeable for $st {
 388                         fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
 389                                 write_tlv_fields!(writer, {
 390                                         $(($type, self.$field, $fieldty)),*
 391                                 });
 392                                 Ok(())
 393                         }
 394
 395                         #[inline]
 396                         fn serialized_length(&self) -> usize {
 397                                 use util::ser::BigSize;
 398                                 let len = {
 399                                         #[allow(unused_mut)]
 400                                         let mut len = ::util::ser::LengthCalculatingWriter(0);
 401                                         $(
 402                                                 get_varint_length_prefixed_tlv_length!(len, $type, self.$field, $fieldty);
 403                                         )*
 404                                         len.0
 405                                 };
 406                                 let mut len_calc = ::util::ser::LengthCalculatingWriter(0);
 407                                 BigSize(len as u64).write(&mut len_calc).expect("No in-memory data may fail to serialize");
 408                                 len + len_calc.0
 409                         }
 410                 }
 411
 412                 impl ::util::ser::Readable for $st {
 413                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, ::ln::msgs::DecodeError> {
 414                                 $(
 415                                         init_tlv_field_var!($field, $fieldty);
 416                                 )*
 417                                 read_tlv_fields!(reader, {
 418                                         $(($type, $field, $fieldty)),*
 419                                 });
 420                                 Ok(Self {
 421                                         $(
 422                                                 $field: init_tlv_based_struct_field!($field, $fieldty)
 423                                         ),*
 424                                 })
 425                         }
 426                 }
 427         }
 428 }
 429
 430 macro_rules! _impl_writeable_tlv_based_enum_common {
 431         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
 432                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 433         ),* $(,)*;
 434         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*) => {
 435                 impl ::util::ser::Writeable for $st {
 436                         fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), $crate::io::Error> {
 437                                 match self {
 438                                         $($st::$variant_name { $(ref $field),* } => {
 439                                                 let id: u8 = $variant_id;
 440                                                 id.write(writer)?;
 441                                                 write_tlv_fields!(writer, {
 442                                                         $(($type, $field, $fieldty)),*
 443                                                 });
 444                                         }),*
 445                                         $($st::$tuple_variant_name (ref field) => {
 446                                                 let id: u8 = $tuple_variant_id;
 447                                                 id.write(writer)?;
 448                                                 field.write(writer)?;
 449                                         }),*
 450                                 }
 451                                 Ok(())
 452                         }
 453                 }
 454         }
 455 }
 456
 457 /// Implement MaybeReadable and Writeable for an enum, with struct variants stored as TLVs and
 458 /// tuple variants stored directly.
 459 ///
 460 /// This is largely identical to `impl_writeable_tlv_based_enum`, except that odd variants will
 461 /// return `Ok(None)` instead of `Err(UnknownRequiredFeature)`. It should generally be preferred
 462 /// when `MaybeReadable` is practical instead of just `Readable` as it provides an upgrade path for
 463 /// new variants to be added which are simply ignored by existing clients.
 464 macro_rules! impl_writeable_tlv_based_enum_upgradable {
 465         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
 466                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 467         ),* $(,)*
 468         $(;
 469         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*)*) => {
 470                 _impl_writeable_tlv_based_enum_common!($st,
 471                         $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
 472                         $($(($tuple_variant_id, $tuple_variant_name)),*)*);
 473
 474                 impl ::util::ser::MaybeReadable for $st {
 475                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Option<Self>, ::ln::msgs::DecodeError> {
 476                                 let id: u8 = ::util::ser::Readable::read(reader)?;
 477                                 match id {
 478                                         $($variant_id => {
 479                                                 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
 480                                                 // in the same function body. Instead, we define a closure and call it.
 481                                                 let f = || {
 482                                                         $(
 483                                                                 init_tlv_field_var!($field, $fieldty);
 484                                                         )*
 485                                                         read_tlv_fields!(reader, {
 486                                                                 $(($type, $field, $fieldty)),*
 487                                                         });
 488                                                         Ok(Some($st::$variant_name {
 489                                                                 $(
 490                                                                         $field: init_tlv_based_struct_field!($field, $fieldty)
 491                                                                 ),*
 492                                                         }))
 493                                                 };
 494                                                 f()
 495                                         }),*
 496                                         $($($tuple_variant_id => {
 497                                                 Ok(Some($st::$tuple_variant_name(Readable::read(reader)?)))
 498                                         }),*)*
 499                                         _ if id % 2 == 1 => Ok(None),
 500                                         _ => Err(DecodeError::UnknownRequiredFeature),
 501                                 }
 502                         }
 503                 }
 504
 505         }
 506 }
 507
 508 /// Implement Readable and Writeable for an enum, with struct variants stored as TLVs and tuple
 509 /// variants stored directly.
 510 /// The format is, for example
 511 /// impl_writeable_tlv_based_enum!(EnumName,
 512 ///   (0, StructVariantA) => {(0, required_variant_field, required), (1, optional_variant_field, option)},
 513 ///   (1, StructVariantB) => {(0, variant_field_a, required), (1, variant_field_b, required), (2, variant_vec_field, vec_type)};
 514 ///   (2, TupleVariantA), (3, TupleVariantB),
 515 /// );
 516 /// The type is written as a single byte, followed by any variant data.
 517 /// Attempts to read an unknown type byte result in DecodeError::UnknownRequiredFeature.
 518 macro_rules! impl_writeable_tlv_based_enum {
 519         ($st: ident, $(($variant_id: expr, $variant_name: ident) =>
 520                 {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 521         ),* $(,)*;
 522         $(($tuple_variant_id: expr, $tuple_variant_name: ident)),*  $(,)*) => {
 523                 _impl_writeable_tlv_based_enum_common!($st,
 524                         $(($variant_id, $variant_name) => {$(($type, $field, $fieldty)),*}),*;
 525                         $(($tuple_variant_id, $tuple_variant_name)),*);
 526
 527                 impl ::util::ser::Readable for $st {
 528                         fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, ::ln::msgs::DecodeError> {
 529                                 let id: u8 = ::util::ser::Readable::read(reader)?;
 530                                 match id {
 531                                         $($variant_id => {
 532                                                 // Because read_tlv_fields creates a labeled loop, we cannot call it twice
 533                                                 // in the same function body. Instead, we define a closure and call it.
 534                                                 let f = || {
 535                                                         $(
 536                                                                 init_tlv_field_var!($field, $fieldty);
 537                                                         )*
 538                                                         read_tlv_fields!(reader, {
 539                                                                 $(($type, $field, $fieldty)),*
 540                                                         });
 541                                                         Ok($st::$variant_name {
 542                                                                 $(
 543                                                                         $field: init_tlv_based_struct_field!($field, $fieldty)
 544                                                                 ),*
 545                                                         })
 546                                                 };
 547                                                 f()
 548                                         }),*
 549                                         $($tuple_variant_id => {
 550                                                 Ok($st::$tuple_variant_name(Readable::read(reader)?))
 551                                         }),*
 552                                         _ => {
 553                                                 Err(DecodeError::UnknownRequiredFeature)
 554                                         },
 555                                 }
 556                         }
 557                 }
 558         }
 559 }
 560
 561 #[cfg(test)]
 562 mod tests {
 563         use io::{self, Cursor};
 564         use prelude::*;
 565         use ln::msgs::DecodeError;
 566         use util::ser::{Writeable, HighZeroBytesDroppedBigSize, VecWriter};
 567         use bitcoin::secp256k1::PublicKey;
 568
 569         // The BOLT TLV test cases don't include any tests which use our "required-value" logic since
 570         // the encoding layer in the BOLTs has no such concept, though it makes our macros easier to
 571         // work with so they're baked into the decoder. Thus, we have a few additional tests below
 572         fn tlv_reader(s: &[u8]) -> Result<(u64, u32, Option<u32>), DecodeError> {
 573                 let mut s = Cursor::new(s);
 574                 let mut a: u64 = 0;
 575                 let mut b: u32 = 0;
 576                 let mut c: Option<u32> = None;
 577                 decode_tlv_stream!(&mut s, {(2, a, required), (3, b, required), (4, c, option)});
 578                 Ok((a, b, c))
 579         }
 580
 581         #[test]
 582         fn tlv_v_short_read() {
 583                 // We only expect a u32 for type 3 (which we are given), but the L says its 8 bytes.
 584                 if let Err(DecodeError::ShortRead) = tlv_reader(&::hex::decode(
 585                                 concat!("0100", "0208deadbeef1badbeef", "0308deadbeef")
 586                                 ).unwrap()[..]) {
 587                 } else { panic!(); }
 588         }
 589
 590         #[test]
 591         fn tlv_types_out_of_order() {
 592                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 593                                 concat!("0100", "0304deadbeef", "0208deadbeef1badbeef")
 594                                 ).unwrap()[..]) {
 595                 } else { panic!(); }
 596                 // ...even if its some field we don't understand
 597                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 598                                 concat!("0208deadbeef1badbeef", "0100", "0304deadbeef")
 599                                 ).unwrap()[..]) {
 600                 } else { panic!(); }
 601         }
 602
 603         #[test]
 604         fn tlv_req_type_missing_or_extra() {
 605                 // It's also bad if they included even fields we don't understand
 606                 if let Err(DecodeError::UnknownRequiredFeature) = tlv_reader(&::hex::decode(
 607                                 concat!("0100", "0208deadbeef1badbeef", "0304deadbeef", "0600")
 608                                 ).unwrap()[..]) {
 609                 } else { panic!(); }
 610                 // ... or if they're missing fields we need
 611                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 612                                 concat!("0100", "0208deadbeef1badbeef")
 613                                 ).unwrap()[..]) {
 614                 } else { panic!(); }
 615                 // ... even if that field is even
 616                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 617                                 concat!("0304deadbeef", "0500")
 618                                 ).unwrap()[..]) {
 619                 } else { panic!(); }
 620         }
 621
 622         #[test]
 623         fn tlv_simple_good_cases() {
 624                 assert_eq!(tlv_reader(&::hex::decode(
 625                                 concat!("0208deadbeef1badbeef", "03041bad1dea")
 626                                 ).unwrap()[..]).unwrap(),
 627                         (0xdeadbeef1badbeef, 0x1bad1dea, None));
 628                 assert_eq!(tlv_reader(&::hex::decode(
 629                                 concat!("0208deadbeef1badbeef", "03041bad1dea", "040401020304")
 630                                 ).unwrap()[..]).unwrap(),
 631                         (0xdeadbeef1badbeef, 0x1bad1dea, Some(0x01020304)));
 632         }
 633
 634         // BOLT TLV test cases
 635         fn tlv_reader_n1(s: &[u8]) -> Result<(Option<HighZeroBytesDroppedBigSize<u64>>, Option<u64>, Option<(PublicKey, u64, u64)>, Option<u16>), DecodeError> {
 636                 let mut s = Cursor::new(s);
 637                 let mut tlv1: Option<HighZeroBytesDroppedBigSize<u64>> = None;
 638                 let mut tlv2: Option<u64> = None;
 639                 let mut tlv3: Option<(PublicKey, u64, u64)> = None;
 640                 let mut tlv4: Option<u16> = None;
 641                 decode_tlv_stream!(&mut s, {(1, tlv1, option), (2, tlv2, option), (3, tlv3, option), (254, tlv4, option)});
 642                 Ok((tlv1, tlv2, tlv3, tlv4))
 643         }
 644
 645         #[test]
 646         fn bolt_tlv_bogus_stream() {
 647                 macro_rules! do_test {
 648                         ($stream: expr, $reason: ident) => {
 649                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
 650                                 } else { panic!(); }
 651                         }
 652                 }
 653
 654                 // TLVs from the BOLT test cases which should not decode as either n1 or n2
 655                 do_test!(concat!("fd01"), ShortRead);
 656                 do_test!(concat!("fd0001", "00"), InvalidValue);
 657                 do_test!(concat!("fd0101"), ShortRead);
 658                 do_test!(concat!("0f", "fd"), ShortRead);
 659                 do_test!(concat!("0f", "fd26"), ShortRead);
 660                 do_test!(concat!("0f", "fd2602"), ShortRead);
 661                 do_test!(concat!("0f", "fd0001", "00"), InvalidValue);
 662                 do_test!(concat!("0f", "fd0201", "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), ShortRead);
 663
 664                 do_test!(concat!("12", "00"), UnknownRequiredFeature);
 665                 do_test!(concat!("fd0102", "00"), UnknownRequiredFeature);
 666                 do_test!(concat!("fe01000002", "00"), UnknownRequiredFeature);
 667                 do_test!(concat!("ff0100000000000002", "00"), UnknownRequiredFeature);
 668         }
 669
 670         #[test]
 671         fn bolt_tlv_bogus_n1_stream() {
 672                 macro_rules! do_test {
 673                         ($stream: expr, $reason: ident) => {
 674                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
 675                                 } else { panic!(); }
 676                         }
 677                 }
 678
 679                 // TLVs from the BOLT test cases which should not decode as n1
 680                 do_test!(concat!("01", "09", "ffffffffffffffffff"), InvalidValue);
 681                 do_test!(concat!("01", "01", "00"), InvalidValue);
 682                 do_test!(concat!("01", "02", "0001"), InvalidValue);
 683                 do_test!(concat!("01", "03", "000100"), InvalidValue);
 684                 do_test!(concat!("01", "04", "00010000"), InvalidValue);
 685                 do_test!(concat!("01", "05", "0001000000"), InvalidValue);
 686                 do_test!(concat!("01", "06", "000100000000"), InvalidValue);
 687                 do_test!(concat!("01", "07", "00010000000000"), InvalidValue);
 688                 do_test!(concat!("01", "08", "0001000000000000"), InvalidValue);
 689                 do_test!(concat!("02", "07", "01010101010101"), ShortRead);
 690                 do_test!(concat!("02", "09", "010101010101010101"), InvalidValue);
 691                 do_test!(concat!("03", "21", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb"), ShortRead);
 692                 do_test!(concat!("03", "29", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001"), ShortRead);
 693                 do_test!(concat!("03", "30", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb000000000000000100000000000001"), ShortRead);
 694                 do_test!(concat!("03", "31", "043da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"), InvalidValue);
 695                 do_test!(concat!("03", "32", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001000000000000000001"), InvalidValue);
 696                 do_test!(concat!("fd00fe", "00"), ShortRead);
 697                 do_test!(concat!("fd00fe", "01", "01"), ShortRead);
 698                 do_test!(concat!("fd00fe", "03", "010101"), InvalidValue);
 699                 do_test!(concat!("00", "00"), UnknownRequiredFeature);
 700
 701                 do_test!(concat!("02", "08", "0000000000000226", "01", "01", "2a"), InvalidValue);
 702                 do_test!(concat!("02", "08", "0000000000000231", "02", "08", "0000000000000451"), InvalidValue);
 703                 do_test!(concat!("1f", "00", "0f", "01", "2a"), InvalidValue);
 704                 do_test!(concat!("1f", "00", "1f", "01", "2a"), InvalidValue);
 705
 706                 // The last BOLT test modified to not require creating a new decoder for one trivial test.
 707                 do_test!(concat!("ffffffffffffffffff", "00", "01", "00"), InvalidValue);
 708         }
 709
 710         #[test]
 711         fn bolt_tlv_valid_n1_stream() {
 712                 macro_rules! do_test {
 713                         ($stream: expr, $tlv1: expr, $tlv2: expr, $tlv3: expr, $tlv4: expr) => {
 714                                 if let Ok((tlv1, tlv2, tlv3, tlv4)) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
 715                                         assert_eq!(tlv1.map(|v| v.0), $tlv1);
 716                                         assert_eq!(tlv2, $tlv2);
 717                                         assert_eq!(tlv3, $tlv3);
 718                                         assert_eq!(tlv4, $tlv4);
 719                                 } else { panic!(); }
 720                         }
 721                 }
 722
 723                 do_test!(concat!(""), None, None, None, None);
 724                 do_test!(concat!("21", "00"), None, None, None, None);
 725                 do_test!(concat!("fd0201", "00"), None, None, None, None);
 726                 do_test!(concat!("fd00fd", "00"), None, None, None, None);
 727                 do_test!(concat!("fd00ff", "00"), None, None, None, None);
 728                 do_test!(concat!("fe02000001", "00"), None, None, None, None);
 729                 do_test!(concat!("ff0200000000000001", "00"), None, None, None, None);
 730
 731                 do_test!(concat!("01", "00"), Some(0), None, None, None);
 732                 do_test!(concat!("01", "01", "01"), Some(1), None, None, None);
 733                 do_test!(concat!("01", "02", "0100"), Some(256), None, None, None);
 734                 do_test!(concat!("01", "03", "010000"), Some(65536), None, None, None);
 735                 do_test!(concat!("01", "04", "01000000"), Some(16777216), None, None, None);
 736                 do_test!(concat!("01", "05", "0100000000"), Some(4294967296), None, None, None);
 737                 do_test!(concat!("01", "06", "010000000000"), Some(1099511627776), None, None, None);
 738                 do_test!(concat!("01", "07", "01000000000000"), Some(281474976710656), None, None, None);
 739                 do_test!(concat!("01", "08", "0100000000000000"), Some(72057594037927936), None, None, None);
 740                 do_test!(concat!("02", "08", "0000000000000226"), None, Some((0 << 30) | (0 << 5) | (550 << 0)), None, None);
 741                 do_test!(concat!("03", "31", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"),
 742                         None, None, Some((
 743                                 PublicKey::from_slice(&::hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]).unwrap(), 1, 2)),
 744                         None);
 745                 do_test!(concat!("fd00fe", "02", "0226"), None, None, None, Some(550));
 746         }
 747
 748         fn do_simple_test_tlv_write() -> Result<(), io::Error> {
 749                 let mut stream = VecWriter(Vec::new());
 750
 751                 stream.0.clear();
 752                 encode_varint_length_prefixed_tlv!(&mut stream, {(1, 1u8, required), (42, None::<u64>, option)});
 753                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
 754
 755                 stream.0.clear();
 756                 encode_varint_length_prefixed_tlv!(&mut stream, {(1, Some(1u8), option)});
 757                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
 758
 759                 stream.0.clear();
 760                 encode_varint_length_prefixed_tlv!(&mut stream, {(4, 0xabcdu16, required), (42, None::<u64>, option)});
 761                 assert_eq!(stream.0, ::hex::decode("040402abcd").unwrap());
 762
 763                 stream.0.clear();
 764                 encode_varint_length_prefixed_tlv!(&mut stream, {(42, None::<u64>, option), (0xff, 0xabcdu16, required)});
 765                 assert_eq!(stream.0, ::hex::decode("06fd00ff02abcd").unwrap());
 766
 767                 stream.0.clear();
 768                 encode_varint_length_prefixed_tlv!(&mut stream, {(0, 1u64, required), (42, None::<u64>, option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
 769                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
 770
 771                 stream.0.clear();
 772                 encode_varint_length_prefixed_tlv!(&mut stream, {(0, Some(1u64), option), (0xff, HighZeroBytesDroppedBigSize(0u64), required)});
 773                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
 774
 775                 Ok(())
 776         }
 777
 778         #[test]
 779         fn simple_test_tlv_write() {
 780                 do_simple_test_tlv_write().unwrap();
 781         }
 782 }