_ 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, $field: expr)),*}, {$(($optional_type: expr, $optional_field: expr)),*}) => {
  12                 encode_tlv!(::util::ser::BigSize, $stream, {$(($type, $field)),*}, {$(($optional_type, $optional_field)),*});
  13         };
  14         ($name_ty: path, $stream: expr, {$(($type: expr, $field: expr)),*}, {$(($optional_type: expr, $optional_field: expr)),*}) => { {
  15                 #[allow(unused_imports)]
  16                 use util::ser::BigSize;
  17                 // Fields must be serialized in order, so we have to potentially switch between optional
  18                 // fields and normal fields while serializing. Thus, we end up having to loop over the type
  19                 // counts.
  20                 // Sadly, while LLVM does appear smart enough to make `max_field` a constant, it appears to
  21                 // refuse to unroll the loop. If we have enough entries that this is slow we can revisit
  22                 // this design in the future.
  23                 #[allow(unused_mut)]
  24                 let mut max_field: u64 = 0;
  25                 $(
  26                         if $type + 1 >= max_field { max_field = $type + 1; }
  27                 )*
  28                 $(
  29                         if $optional_type + 1 >= max_field { max_field = $optional_type + 1; }
  30                 )*
  31                 #[allow(unused_variables)]
  32                 for i in 0..max_field {
  33                         $(
  34                                 if i == $type {
  35                                         $name_ty($type).write($stream)?;
  36                                         BigSize($field.serialized_length() as u64).write($stream)?;
  37                                         $field.write($stream)?;
  38                                 }
  39                         )*
  40                         $(
  41                                 if i == $optional_type {
  42                                         if let Some(ref field) = $optional_field {
  43                                                 $name_ty($optional_type).write($stream)?;
  44                                                 BigSize(field.serialized_length() as u64).write($stream)?;
  45                                                 field.write($stream)?;
  46                                         }
  47                                 }
  48                         )*
  49                 }
  50         } }
  51 }
  52
  53 macro_rules! get_varint_length_prefixed_tlv_length {
  54         ($name_ty: path, {$(($type: expr, $field: expr)),*}, {$(($optional_type: expr, $optional_field: expr)),* $(,)*}) => { {
  55                 use util::ser::LengthCalculatingWriter;
  56                 #[allow(unused_mut)]
  57                 let mut len = LengthCalculatingWriter(0);
  58                 {
  59                         $(
  60                                 $name_ty($type).write(&mut len).expect("No in-memory data may fail to serialize");
  61                                 let field_len = $field.serialized_length();
  62                                 BigSize(field_len as u64).write(&mut len).expect("No in-memory data may fail to serialize");
  63                                 len.0 += field_len;
  64                         )*
  65                         $(
  66                                 if let Some(ref field) = $optional_field {
  67                                         $name_ty($optional_type).write(&mut len).expect("No in-memory data may fail to serialize");
  68                                         let field_len = field.serialized_length();
  69                                         BigSize(field_len as u64).write(&mut len).expect("No in-memory data may fail to serialize");
  70                                         len.0 += field_len;
  71                                 }
  72                         )*
  73                 }
  74                 len.0
  75         } }
  76 }
  77
  78 macro_rules! encode_varint_length_prefixed_tlv {
  79         ($stream: expr, {$(($type: expr, $field: expr)),*}, {$(($optional_type: expr, $optional_field: expr)),*}) => {
  80                 encode_varint_length_prefixed_tlv!(::util::ser::BigSize, $stream, {$(($type, $field)),*}, {$(($optional_type, $optional_field)),*});
  81         };
  82         ($name_ty: path, $stream: expr, {$(($type: expr, $field: expr)),*}, {$(($optional_type: expr, $optional_field: expr)),*}) => { {
  83                 use util::ser::BigSize;
  84                 let len = get_varint_length_prefixed_tlv_length!($name_ty, { $(($type, $field)),* }, { $(($optional_type, $optional_field)),* });
  85                 BigSize(len as u64).write($stream)?;
  86                 encode_tlv!($stream, { $(($type, $field)),* }, { $(($optional_type, $optional_field)),* });
  87         } }
  88 }
  89
  90 macro_rules! decode_tlv {
  91         ($stream: expr, {$(($reqtype: expr, $reqfield: ident)),*}, {$(($type: expr, $field: ident)),*}) => {
  92                 decode_tlv!(::util::ser::BigSize, $stream, {$(($reqtype, $reqfield)),*}, {$(($type, $field)),*});
  93         };
  94         ($name_ty: path, $stream: expr, {$(($reqtype: expr, $reqfield: ident)),*}, {$(($type: expr, $field: ident)),*}) => { {
  95                 use ln::msgs::DecodeError;
  96                 let mut last_seen_type = None;
  97                 'tlv_read: loop {
  98                         use util::ser;
  99
 100                         // First decode the type of this TLV:
 101                         let typ: $name_ty = {
 102                                 // We track whether any bytes were read during the consensus_decode call to
 103                                 // determine whether we should break or return ShortRead if we get an
 104                                 // UnexpectedEof. This should in every case be largely cosmetic, but its nice to
 105                                 // pass the TLV test vectors exactly, which requre this distinction.
 106                                 let mut tracking_reader = ser::ReadTrackingReader::new($stream);
 107                                 match ser::Readable::read(&mut tracking_reader) {
 108                                         Err(DecodeError::ShortRead) => {
 109                                                 if !tracking_reader.have_read {
 110                                                         break 'tlv_read
 111                                                 } else {
 112                                                         Err(DecodeError::ShortRead)?
 113                                                 }
 114                                         },
 115                                         Err(e) => Err(e)?,
 116                                         Ok(t) => t,
 117                                 }
 118                         };
 119
 120                         // Types must be unique and monotonically increasing:
 121                         match last_seen_type {
 122                                 Some(t) if typ.0 <= t => {
 123                                         Err(DecodeError::InvalidValue)?
 124                                 },
 125                                 _ => {},
 126                         }
 127                         // As we read types, make sure we hit every required type:
 128                         $({
 129                                 #[allow(unused_comparisons)] // Note that $reqtype may be 0 making the second comparison always true
 130                                 let invalid_order = (last_seen_type.is_none() || last_seen_type.unwrap() < $reqtype) && typ.0 > $reqtype;
 131                                 if invalid_order {
 132                                         Err(DecodeError::InvalidValue)?
 133                                 }
 134                         })*
 135                         last_seen_type = Some(typ.0);
 136
 137                         // Finally, read the length and value itself:
 138                         let length: ser::BigSize = Readable::read($stream)?;
 139                         let mut s = ser::FixedLengthReader::new($stream, length.0);
 140                         match typ.0 {
 141                                 $($reqtype => {
 142                                         $reqfield = ser::Readable::read(&mut s)?;
 143                                         if s.bytes_remain() {
 144                                                 s.eat_remaining()?; // Return ShortRead if there's actually not enough bytes
 145                                                 Err(DecodeError::InvalidValue)?
 146                                         }
 147                                 },)*
 148                                 $($type => {
 149                                         $field = Some(ser::Readable::read(&mut s)?);
 150                                         if s.bytes_remain() {
 151                                                 s.eat_remaining()?; // Return ShortRead if there's actually not enough bytes
 152                                                 Err(DecodeError::InvalidValue)?
 153                                         }
 154                                 },)*
 155                                 x if x % 2 == 0 => {
 156                                         Err(DecodeError::UnknownRequiredFeature)?
 157                                 },
 158                                 _ => {},
 159                         }
 160                         s.eat_remaining()?;
 161                 }
 162                 // Make sure we got to each required type after we've read every TLV:
 163                 $({
 164                         #[allow(unused_comparisons)] // Note that $reqtype may be 0 making the second comparison always true
 165                         let missing_req_type = last_seen_type.is_none() || last_seen_type.unwrap() < $reqtype;
 166                         if missing_req_type {
 167                                 Err(DecodeError::InvalidValue)?
 168                         }
 169                 })*
 170         } }
 171 }
 172
 173 macro_rules! impl_writeable {
 174         ($st:ident, $len: expr, {$($field:ident),*}) => {
 175                 impl ::util::ser::Writeable for $st {
 176                         fn write<W: ::util::ser::Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
 177                                 if $len != 0 {
 178                                         w.size_hint($len);
 179                                 }
 180                                 #[cfg(any(test, feature = "fuzztarget"))]
 181                                 {
 182                                         // In tests, assert that the hard-coded length matches the actual one
 183                                         if $len != 0 {
 184                                                 use util::ser::LengthCalculatingWriter;
 185                                                 let mut len_calc = LengthCalculatingWriter(0);
 186                                                 $( self.$field.write(&mut len_calc).expect("No in-memory data may fail to serialize"); )*
 187                                                 assert_eq!(len_calc.0, $len);
 188                                         }
 189                                 }
 190                                 $( self.$field.write(w)?; )*
 191                                 Ok(())
 192                         }
 193
 194                         #[inline]
 195                         fn serialized_length(&self) -> usize {
 196                                 if $len == 0 || cfg!(any(test, feature = "fuzztarget")) {
 197                                         let mut len_calc = 0;
 198                                         $( len_calc += self.$field.serialized_length(); )*
 199                                         if $len != 0 {
 200                                                 // In tests, assert that the hard-coded length matches the actual one
 201                                                 assert_eq!(len_calc, $len);
 202                                         } else {
 203                                                 return len_calc;
 204                                         }
 205                                 }
 206                                 $len
 207                         }
 208                 }
 209
 210                 impl ::util::ser::Readable for $st {
 211                         fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, ::ln::msgs::DecodeError> {
 212                                 Ok(Self {
 213                                         $($field: ::util::ser::Readable::read(r)?),*
 214                                 })
 215                         }
 216                 }
 217         }
 218 }
 219 macro_rules! impl_writeable_len_match {
 220         ($struct: ident, $cmp: tt, ($calc_len: expr), {$({$match: pat, $length: expr}),*}, {$($field:ident),*}) => {
 221                 impl Writeable for $struct {
 222                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
 223                                 let len = match *self {
 224                                         $($match => $length,)*
 225                                 };
 226                                 w.size_hint(len);
 227                                 #[cfg(any(test, feature = "fuzztarget"))]
 228                                 {
 229                                         // In tests, assert that the hard-coded length matches the actual one
 230                                         use util::ser::LengthCalculatingWriter;
 231                                         let mut len_calc = LengthCalculatingWriter(0);
 232                                         $( self.$field.write(&mut len_calc).expect("No in-memory data may fail to serialize"); )*
 233                                         assert!(len_calc.0 $cmp len);
 234                                 }
 235                                 $( self.$field.write(w)?; )*
 236                                 Ok(())
 237                         }
 238
 239                         #[inline]
 240                         fn serialized_length(&self) -> usize {
 241                                 if $calc_len || cfg!(any(test, feature = "fuzztarget")) {
 242                                         let mut len_calc = 0;
 243                                         $( len_calc += self.$field.serialized_length(); )*
 244                                         if !$calc_len {
 245                                                 assert_eq!(len_calc, match *self {
 246                                                         $($match => $length,)*
 247                                                 });
 248                                         }
 249                                         return len_calc
 250                                 }
 251                                 match *self {
 252                                         $($match => $length,)*
 253                                 }
 254                         }
 255                 }
 256
 257                 impl ::util::ser::Readable for $struct {
 258                         fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
 259                                 Ok(Self {
 260                                         $($field: Readable::read(r)?),*
 261                                 })
 262                         }
 263                 }
 264         };
 265         ($struct: ident, $cmp: tt, {$({$match: pat, $length: expr}),*}, {$($field:ident),*}) => {
 266                 impl_writeable_len_match!($struct, $cmp, (true), { $({ $match, $length }),* }, { $($field),* });
 267         };
 268         ($struct: ident, {$({$match: pat, $length: expr}),*}, {$($field:ident),*}) => {
 269                 impl_writeable_len_match!($struct, ==, (false), { $({ $match, $length }),* }, { $($field),* });
 270         }
 271 }
 272
 273 /// Write out two bytes to indicate the version of an object.
 274 /// $this_version represents a unique version of a type. Incremented whenever the type's
 275 ///               serialization format has changed or has a new interpretation. Used by a type's
 276 ///               reader to determine how to interpret fields or if it can understand a serialized
 277 ///               object.
 278 /// $min_version_that_can_read_this is the minimum reader version which can understand this
 279 ///                                 serialized object. Previous versions will simply err with a
 280 ///                                 DecodeError::UnknownVersion.
 281 ///
 282 /// Updates to either $this_version or $min_version_that_can_read_this should be included in
 283 /// release notes.
 284 ///
 285 /// Both version fields can be specific to this type of object.
 286 macro_rules! write_ver_prefix {
 287         ($stream: expr, $this_version: expr, $min_version_that_can_read_this: expr) => {
 288                 $stream.write_all(&[$this_version; 1])?;
 289                 $stream.write_all(&[$min_version_that_can_read_this; 1])?;
 290         }
 291 }
 292
 293 /// Writes out a suffix to an object which contains potentially backwards-compatible, optional
 294 /// fields which old nodes can happily ignore.
 295 ///
 296 /// It is written out in TLV format and, as with all TLV fields, unknown even fields cause a
 297 /// DecodeError::UnknownRequiredFeature error, with unknown odd fields ignored.
 298 ///
 299 /// This is the preferred method of adding new fields that old nodes can ignore and still function
 300 /// correctly.
 301 macro_rules! write_tlv_fields {
 302         ($stream: expr, {$(($type: expr, $field: expr)),* $(,)*}, {$(($optional_type: expr, $optional_field: expr)),* $(,)*}) => {
 303                 encode_varint_length_prefixed_tlv!(::util::ser::U8Wrapper, $stream, {$(($type, $field)),*} , {$(($optional_type, $optional_field)),*});
 304         }
 305 }
 306
 307 /// Reads a prefix added by write_ver_prefix!(), above. Takes the current version of the
 308 /// serialization logic for this object. This is compared against the
 309 /// $min_version_that_can_read_this added by write_ver_prefix!().
 310 macro_rules! read_ver_prefix {
 311         ($stream: expr, $this_version: expr) => { {
 312                 let ver: u8 = Readable::read($stream)?;
 313                 let min_ver: u8 = Readable::read($stream)?;
 314                 if min_ver > $this_version {
 315                         return Err(DecodeError::UnknownVersion);
 316                 }
 317                 ver
 318         } }
 319 }
 320
 321 /// Reads a suffix added by write_tlv_fields.
 322 macro_rules! read_tlv_fields {
 323         ($stream: expr, {$(($reqtype: expr, $reqfield: ident)),* $(,)*}, {$(($type: expr, $field: ident)),* $(,)*}) => { {
 324                 let tlv_len = ::util::ser::BigSize::read($stream)?;
 325                 let mut rd = ::util::ser::FixedLengthReader::new($stream, tlv_len.0);
 326                 decode_tlv!(::util::ser::U8Wrapper, &mut rd, {$(($reqtype, $reqfield)),*}, {$(($type, $field)),*});
 327                 rd.eat_remaining().map_err(|_| DecodeError::ShortRead)?;
 328         } }
 329 }
 330
 331 // If we naively create a struct in impl_writeable_tlv_based below, we may end up returning
 332 // `Self { ,,vecfield: vecfield }` which is obviously incorrect. Instead, we have to match here to
 333 // detect at least one empty field set and skip the potentially-extra comma.
 334 macro_rules! _init_tlv_based_struct {
 335         ({}, {$($field: ident),*}, {$($vecfield: ident),*}) => {
 336                 Ok(Self {
 337                         $($field),*,
 338                         $($vecfield: $vecfield.unwrap().0),*
 339                 })
 340         };
 341         ({$($reqfield: ident),*}, {}, {$($vecfield: ident),*}) => {
 342                 Ok(Self {
 343                         $($reqfield: $reqfield.0.unwrap()),*,
 344                         $($vecfield: $vecfield.unwrap().0),*
 345                 })
 346         };
 347         ({$($reqfield: ident),*}, {$($field: ident),*}, {}) => {
 348                 Ok(Self {
 349                         $($reqfield: $reqfield.0.unwrap()),*,
 350                         $($field),*
 351                 })
 352         };
 353         ({$($reqfield: ident),*}, {$($field: ident),*}, {$($vecfield: ident),*}) => {
 354                 Ok(Self {
 355                         $($reqfield: $reqfield.0.unwrap()),*,
 356                         $($field),*,
 357                         $($vecfield: $vecfield.unwrap().0),*
 358                 })
 359         }
 360 }
 361
 362 // If we don't have any optional types below, but do have some vec types, we end up calling
 363 // `write_tlv_field!($stream, {..}, {, (vec_ty, vec_val)})`, which is obviously broken.
 364 // Instead, for write and read we match the missing values and skip the extra comma.
 365 macro_rules! _write_tlv_fields {
 366         ($stream: expr, {$(($type: expr, $field: expr)),* $(,)*}, {}, {$(($optional_type: expr, $optional_field: expr)),* $(,)*}) => {
 367                 write_tlv_fields!($stream, {$(($type, $field)),*} , {$(($optional_type, $optional_field)),*});
 368         };
 369         ($stream: expr, {$(($type: expr, $field: expr)),* $(,)*}, {$(($optional_type: expr, $optional_field: expr)),* $(,)*}, {$(($optional_type_2: expr, $optional_field_2: expr)),* $(,)*}) => {
 370                 write_tlv_fields!($stream, {$(($type, $field)),*} , {$(($optional_type, $optional_field)),*, $(($optional_type_2, $optional_field_2)),*});
 371         }
 372 }
 373 macro_rules! _get_tlv_len {
 374         ({$(($type: expr, $field: expr)),* $(,)*}, {}, {$(($optional_type: expr, $optional_field: expr)),* $(,)*}) => {
 375                 get_varint_length_prefixed_tlv_length!(::util::ser::U8Wrapper, {$(($type, $field)),*} , {$(($optional_type, $optional_field)),*})
 376         };
 377         ({$(($type: expr, $field: expr)),* $(,)*}, {$(($optional_type: expr, $optional_field: expr)),* $(,)*}, {$(($optional_type_2: expr, $optional_field_2: expr)),* $(,)*}) => {
 378                 get_varint_length_prefixed_tlv_length!(::util::ser::U8Wrapper, {$(($type, $field)),*} , {$(($optional_type, $optional_field)),*, $(($optional_type_2, $optional_field_2)),*})
 379         }
 380 }
 381 macro_rules! _read_tlv_fields {
 382         ($stream: expr, {$(($reqtype: expr, $reqfield: ident)),* $(,)*}, {}, {$(($type: expr, $field: ident)),* $(,)*}) => {
 383                 read_tlv_fields!($stream, {$(($reqtype, $reqfield)),*}, {$(($type, $field)),*});
 384         };
 385         ($stream: expr, {$(($reqtype: expr, $reqfield: ident)),* $(,)*}, {$(($type: expr, $field: ident)),* $(,)*}, {$(($type_2: expr, $field_2: ident)),* $(,)*}) => {
 386                 read_tlv_fields!($stream, {$(($reqtype, $reqfield)),*}, {$(($type, $field)),*, $(($type_2, $field_2)),*});
 387         }
 388 }
 389
 390 /// Implements Readable/Writeable for a struct storing it as a set of TLVs
 391 /// First block includes all the required fields including a dummy value which is used during
 392 /// deserialization but which will never be exposed to other code.
 393 /// The second block includes optional fields.
 394 /// The third block includes any Vecs which need to have their individual elements serialized.
 395 macro_rules! impl_writeable_tlv_based {
 396         ($st: ident, {$(($reqtype: expr, $reqfield: ident)),* $(,)*}, {$(($type: expr, $field: ident)),* $(,)*}, {$(($vectype: expr, $vecfield: ident)),* $(,)*}) => {
 397                 impl ::util::ser::Writeable for $st {
 398                         fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 399                                 _write_tlv_fields!(writer, {
 400                                         $(($reqtype, self.$reqfield)),*
 401                                 }, {
 402                                         $(($type, self.$field)),*
 403                                 }, {
 404                                         $(($vectype, Some(::util::ser::VecWriteWrapper(&self.$vecfield)))),*
 405                                 });
 406                                 Ok(())
 407                         }
 408
 409                         #[inline]
 410                         fn serialized_length(&self) -> usize {
 411                                 let len = _get_tlv_len!({
 412                                         $(($reqtype, self.$reqfield)),*
 413                                 }, {
 414                                         $(($type, self.$field)),*
 415                                 }, {
 416                                         $(($vectype, Some(::util::ser::VecWriteWrapper(&self.$vecfield)))),*
 417                                 });
 418                                 use util::ser::{BigSize, LengthCalculatingWriter};
 419                                 let mut len_calc = LengthCalculatingWriter(0);
 420                                 BigSize(len as u64).write(&mut len_calc).expect("No in-memory data may fail to serialize");
 421                                 len + len_calc.0
 422                         }
 423                 }
 424
 425                 impl ::util::ser::Readable for $st {
 426                         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, ::ln::msgs::DecodeError> {
 427                                 $(
 428                                         let mut $reqfield = ::util::ser::OptionDeserWrapper(None);
 429                                 )*
 430                                 $(
 431                                         let mut $field = None;
 432                                 )*
 433                                 $(
 434                                         let mut $vecfield = Some(::util::ser::VecReadWrapper(Vec::new()));
 435                                 )*
 436                                 _read_tlv_fields!(reader, {
 437                                         $(($reqtype, $reqfield)),*
 438                                 }, {
 439                                         $(($type, $field)),*
 440                                 }, {
 441                                         $(($vectype, $vecfield)),*
 442                                 });
 443                                 _init_tlv_based_struct!({$($reqfield),*}, {$($field),*}, {$($vecfield),*})
 444                         }
 445                 }
 446         }
 447 }
 448
 449 #[cfg(test)]
 450 mod tests {
 451         use prelude::*;
 452         use std::io::{Cursor, Read};
 453         use ln::msgs::DecodeError;
 454         use util::ser::{Readable, Writeable, HighZeroBytesDroppedVarInt, VecWriter};
 455         use bitcoin::secp256k1::PublicKey;
 456
 457         // The BOLT TLV test cases don't include any tests which use our "required-value" logic since
 458         // the encoding layer in the BOLTs has no such concept, though it makes our macros easier to
 459         // work with so they're baked into the decoder. Thus, we have a few additional tests below
 460         fn tlv_reader(s: &[u8]) -> Result<(u64, u32, Option<u32>), DecodeError> {
 461                 let mut s = Cursor::new(s);
 462                 let mut a: u64 = 0;
 463                 let mut b: u32 = 0;
 464                 let mut c: Option<u32> = None;
 465                 decode_tlv!(&mut s, {(2, a), (3, b)}, {(4, c)});
 466                 Ok((a, b, c))
 467         }
 468
 469         #[test]
 470         fn tlv_v_short_read() {
 471                 // We only expect a u32 for type 3 (which we are given), but the L says its 8 bytes.
 472                 if let Err(DecodeError::ShortRead) = tlv_reader(&::hex::decode(
 473                                 concat!("0100", "0208deadbeef1badbeef", "0308deadbeef")
 474                                 ).unwrap()[..]) {
 475                 } else { panic!(); }
 476         }
 477
 478         #[test]
 479         fn tlv_types_out_of_order() {
 480                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 481                                 concat!("0100", "0304deadbeef", "0208deadbeef1badbeef")
 482                                 ).unwrap()[..]) {
 483                 } else { panic!(); }
 484                 // ...even if its some field we don't understand
 485                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 486                                 concat!("0208deadbeef1badbeef", "0100", "0304deadbeef")
 487                                 ).unwrap()[..]) {
 488                 } else { panic!(); }
 489         }
 490
 491         #[test]
 492         fn tlv_req_type_missing_or_extra() {
 493                 // It's also bad if they included even fields we don't understand
 494                 if let Err(DecodeError::UnknownRequiredFeature) = tlv_reader(&::hex::decode(
 495                                 concat!("0100", "0208deadbeef1badbeef", "0304deadbeef", "0600")
 496                                 ).unwrap()[..]) {
 497                 } else { panic!(); }
 498                 // ... or if they're missing fields we need
 499                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 500                                 concat!("0100", "0208deadbeef1badbeef")
 501                                 ).unwrap()[..]) {
 502                 } else { panic!(); }
 503                 // ... even if that field is even
 504                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
 505                                 concat!("0304deadbeef", "0500")
 506                                 ).unwrap()[..]) {
 507                 } else { panic!(); }
 508         }
 509
 510         #[test]
 511         fn tlv_simple_good_cases() {
 512                 assert_eq!(tlv_reader(&::hex::decode(
 513                                 concat!("0208deadbeef1badbeef", "03041bad1dea")
 514                                 ).unwrap()[..]).unwrap(),
 515                         (0xdeadbeef1badbeef, 0x1bad1dea, None));
 516                 assert_eq!(tlv_reader(&::hex::decode(
 517                                 concat!("0208deadbeef1badbeef", "03041bad1dea", "040401020304")
 518                                 ).unwrap()[..]).unwrap(),
 519                         (0xdeadbeef1badbeef, 0x1bad1dea, Some(0x01020304)));
 520         }
 521
 522         impl Readable for (PublicKey, u64, u64) {
 523                 #[inline]
 524                 fn read<R: Read>(reader: &mut R) -> Result<(PublicKey, u64, u64), DecodeError> {
 525                         Ok((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?))
 526                 }
 527         }
 528
 529         // BOLT TLV test cases
 530         fn tlv_reader_n1(s: &[u8]) -> Result<(Option<HighZeroBytesDroppedVarInt<u64>>, Option<u64>, Option<(PublicKey, u64, u64)>, Option<u16>), DecodeError> {
 531                 let mut s = Cursor::new(s);
 532                 let mut tlv1: Option<HighZeroBytesDroppedVarInt<u64>> = None;
 533                 let mut tlv2: Option<u64> = None;
 534                 let mut tlv3: Option<(PublicKey, u64, u64)> = None;
 535                 let mut tlv4: Option<u16> = None;
 536                 decode_tlv!(&mut s, {}, {(1, tlv1), (2, tlv2), (3, tlv3), (254, tlv4)});
 537                 Ok((tlv1, tlv2, tlv3, tlv4))
 538         }
 539
 540         #[test]
 541         fn bolt_tlv_bogus_stream() {
 542                 macro_rules! do_test {
 543                         ($stream: expr, $reason: ident) => {
 544                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
 545                                 } else { panic!(); }
 546                         }
 547                 }
 548
 549                 // TLVs from the BOLT test cases which should not decode as either n1 or n2
 550                 do_test!(concat!("fd01"), ShortRead);
 551                 do_test!(concat!("fd0001", "00"), InvalidValue);
 552                 do_test!(concat!("fd0101"), ShortRead);
 553                 do_test!(concat!("0f", "fd"), ShortRead);
 554                 do_test!(concat!("0f", "fd26"), ShortRead);
 555                 do_test!(concat!("0f", "fd2602"), ShortRead);
 556                 do_test!(concat!("0f", "fd0001", "00"), InvalidValue);
 557                 do_test!(concat!("0f", "fd0201", "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), ShortRead);
 558
 559                 do_test!(concat!("12", "00"), UnknownRequiredFeature);
 560                 do_test!(concat!("fd0102", "00"), UnknownRequiredFeature);
 561                 do_test!(concat!("fe01000002", "00"), UnknownRequiredFeature);
 562                 do_test!(concat!("ff0100000000000002", "00"), UnknownRequiredFeature);
 563         }
 564
 565         #[test]
 566         fn bolt_tlv_bogus_n1_stream() {
 567                 macro_rules! do_test {
 568                         ($stream: expr, $reason: ident) => {
 569                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
 570                                 } else { panic!(); }
 571                         }
 572                 }
 573
 574                 // TLVs from the BOLT test cases which should not decode as n1
 575                 do_test!(concat!("01", "09", "ffffffffffffffffff"), InvalidValue);
 576                 do_test!(concat!("01", "01", "00"), InvalidValue);
 577                 do_test!(concat!("01", "02", "0001"), InvalidValue);
 578                 do_test!(concat!("01", "03", "000100"), InvalidValue);
 579                 do_test!(concat!("01", "04", "00010000"), InvalidValue);
 580                 do_test!(concat!("01", "05", "0001000000"), InvalidValue);
 581                 do_test!(concat!("01", "06", "000100000000"), InvalidValue);
 582                 do_test!(concat!("01", "07", "00010000000000"), InvalidValue);
 583                 do_test!(concat!("01", "08", "0001000000000000"), InvalidValue);
 584                 do_test!(concat!("02", "07", "01010101010101"), ShortRead);
 585                 do_test!(concat!("02", "09", "010101010101010101"), InvalidValue);
 586                 do_test!(concat!("03", "21", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb"), ShortRead);
 587                 do_test!(concat!("03", "29", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001"), ShortRead);
 588                 do_test!(concat!("03", "30", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb000000000000000100000000000001"), ShortRead);
 589                 do_test!(concat!("03", "31", "043da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"), InvalidValue);
 590                 do_test!(concat!("03", "32", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001000000000000000001"), InvalidValue);
 591                 do_test!(concat!("fd00fe", "00"), ShortRead);
 592                 do_test!(concat!("fd00fe", "01", "01"), ShortRead);
 593                 do_test!(concat!("fd00fe", "03", "010101"), InvalidValue);
 594                 do_test!(concat!("00", "00"), UnknownRequiredFeature);
 595
 596                 do_test!(concat!("02", "08", "0000000000000226", "01", "01", "2a"), InvalidValue);
 597                 do_test!(concat!("02", "08", "0000000000000231", "02", "08", "0000000000000451"), InvalidValue);
 598                 do_test!(concat!("1f", "00", "0f", "01", "2a"), InvalidValue);
 599                 do_test!(concat!("1f", "00", "1f", "01", "2a"), InvalidValue);
 600
 601                 // The last BOLT test modified to not require creating a new decoder for one trivial test.
 602                 do_test!(concat!("ffffffffffffffffff", "00", "01", "00"), InvalidValue);
 603         }
 604
 605         #[test]
 606         fn bolt_tlv_valid_n1_stream() {
 607                 macro_rules! do_test {
 608                         ($stream: expr, $tlv1: expr, $tlv2: expr, $tlv3: expr, $tlv4: expr) => {
 609                                 if let Ok((tlv1, tlv2, tlv3, tlv4)) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
 610                                         assert_eq!(tlv1.map(|v| v.0), $tlv1);
 611                                         assert_eq!(tlv2, $tlv2);
 612                                         assert_eq!(tlv3, $tlv3);
 613                                         assert_eq!(tlv4, $tlv4);
 614                                 } else { panic!(); }
 615                         }
 616                 }
 617
 618                 do_test!(concat!(""), None, None, None, None);
 619                 do_test!(concat!("21", "00"), None, None, None, None);
 620                 do_test!(concat!("fd0201", "00"), None, None, None, None);
 621                 do_test!(concat!("fd00fd", "00"), None, None, None, None);
 622                 do_test!(concat!("fd00ff", "00"), None, None, None, None);
 623                 do_test!(concat!("fe02000001", "00"), None, None, None, None);
 624                 do_test!(concat!("ff0200000000000001", "00"), None, None, None, None);
 625
 626                 do_test!(concat!("01", "00"), Some(0), None, None, None);
 627                 do_test!(concat!("01", "01", "01"), Some(1), None, None, None);
 628                 do_test!(concat!("01", "02", "0100"), Some(256), None, None, None);
 629                 do_test!(concat!("01", "03", "010000"), Some(65536), None, None, None);
 630                 do_test!(concat!("01", "04", "01000000"), Some(16777216), None, None, None);
 631                 do_test!(concat!("01", "05", "0100000000"), Some(4294967296), None, None, None);
 632                 do_test!(concat!("01", "06", "010000000000"), Some(1099511627776), None, None, None);
 633                 do_test!(concat!("01", "07", "01000000000000"), Some(281474976710656), None, None, None);
 634                 do_test!(concat!("01", "08", "0100000000000000"), Some(72057594037927936), None, None, None);
 635                 do_test!(concat!("02", "08", "0000000000000226"), None, Some((0 << 30) | (0 << 5) | (550 << 0)), None, None);
 636                 do_test!(concat!("03", "31", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"),
 637                         None, None, Some((
 638                                 PublicKey::from_slice(&::hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]).unwrap(), 1, 2)),
 639                         None);
 640                 do_test!(concat!("fd00fe", "02", "0226"), None, None, None, Some(550));
 641         }
 642
 643         fn do_simple_test_tlv_write() -> Result<(), ::std::io::Error> {
 644                 let mut stream = VecWriter(Vec::new());
 645
 646                 stream.0.clear();
 647                 encode_varint_length_prefixed_tlv!(&mut stream, { (1, 1u8) }, { (42, None::<u64>) });
 648                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
 649
 650                 stream.0.clear();
 651                 encode_varint_length_prefixed_tlv!(&mut stream, { }, { (1, Some(1u8)) });
 652                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
 653
 654                 stream.0.clear();
 655                 encode_varint_length_prefixed_tlv!(&mut stream, { (4, 0xabcdu16) }, { (42, None::<u64>) });
 656                 assert_eq!(stream.0, ::hex::decode("040402abcd").unwrap());
 657
 658                 stream.0.clear();
 659                 encode_varint_length_prefixed_tlv!(&mut stream, { (0xff, 0xabcdu16) }, { (42, None::<u64>) });
 660                 assert_eq!(stream.0, ::hex::decode("06fd00ff02abcd").unwrap());
 661
 662                 stream.0.clear();
 663                 encode_varint_length_prefixed_tlv!(&mut stream, { (0, 1u64), (0xff, HighZeroBytesDroppedVarInt(0u64)) }, { (42, None::<u64>) });
 664                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
 665
 666                 stream.0.clear();
 667                 encode_varint_length_prefixed_tlv!(&mut stream, { (0xff, HighZeroBytesDroppedVarInt(0u64)) }, { (0, Some(1u64)) });
 668                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
 669
 670                 Ok(())
 671         }
 672
 673         #[test]
 674         fn simple_test_tlv_write() {
 675                 do_simple_test_tlv_write().unwrap();
 676         }
 677 }