Relicense as dual Apache-2.0 + MIT
[rust-lightning] / 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)),*}) => { {
12                 use util::ser::{BigSize, LengthCalculatingWriter};
13                 $(
14                         BigSize($type).write($stream)?;
15                         let mut len_calc = LengthCalculatingWriter(0);
16                         $field.write(&mut len_calc)?;
17                         BigSize(len_calc.0 as u64).write($stream)?;
18                         $field.write($stream)?;
19                 )*
20         } }
21 }
22
23 macro_rules! encode_varint_length_prefixed_tlv {
24         ($stream: expr, {$(($type: expr, $field: expr)),*}) => { {
25                 use util::ser::{BigSize, LengthCalculatingWriter};
26                 let mut len = LengthCalculatingWriter(0);
27                 {
28                         $(
29                                 BigSize($type).write(&mut len)?;
30                                 let mut field_len = LengthCalculatingWriter(0);
31                                 $field.write(&mut field_len)?;
32                                 BigSize(field_len.0 as u64).write(&mut len)?;
33                                 len.0 += field_len.0;
34                         )*
35                 }
36
37                 BigSize(len.0 as u64).write($stream)?;
38                 encode_tlv!($stream, {
39                         $(($type, $field)),*
40                 });
41         } }
42 }
43
44 macro_rules! decode_tlv {
45         ($stream: expr, {$(($reqtype: expr, $reqfield: ident)),*}, {$(($type: expr, $field: ident)),*}) => { {
46                 use ln::msgs::DecodeError;
47                 let mut last_seen_type: Option<u64> = None;
48                 'tlv_read: loop {
49                         use util::ser;
50
51                         // First decode the type of this TLV:
52                         let typ: ser::BigSize = {
53                                 // We track whether any bytes were read during the consensus_decode call to
54                                 // determine whether we should break or return ShortRead if we get an
55                                 // UnexpectedEof. This should in every case be largely cosmetic, but its nice to
56                                 // pass the TLV test vectors exactly, which requre this distinction.
57                                 let mut tracking_reader = ser::ReadTrackingReader::new($stream);
58                                 match ser::Readable::read(&mut tracking_reader) {
59                                         Err(DecodeError::ShortRead) => {
60                                                 if !tracking_reader.have_read {
61                                                         break 'tlv_read
62                                                 } else {
63                                                         Err(DecodeError::ShortRead)?
64                                                 }
65                                         },
66                                         Err(e) => Err(e)?,
67                                         Ok(t) => t,
68                                 }
69                         };
70
71                         // Types must be unique and monotonically increasing:
72                         match last_seen_type {
73                                 Some(t) if typ.0 <= t => {
74                                         Err(DecodeError::InvalidValue)?
75                                 },
76                                 _ => {},
77                         }
78                         // As we read types, make sure we hit every required type:
79                         $(if (last_seen_type.is_none() || last_seen_type.unwrap() < $reqtype) && typ.0 > $reqtype {
80                                 Err(DecodeError::InvalidValue)?
81                         })*
82                         last_seen_type = Some(typ.0);
83
84                         // Finally, read the length and value itself:
85                         let length: ser::BigSize = Readable::read($stream)?;
86                         let mut s = ser::FixedLengthReader::new($stream, length.0);
87                         match typ.0 {
88                                 $($reqtype => {
89                                         $reqfield = ser::Readable::read(&mut s)?;
90                                         if s.bytes_remain() {
91                                                 s.eat_remaining()?; // Return ShortRead if there's actually not enough bytes
92                                                 Err(DecodeError::InvalidValue)?
93                                         }
94                                 },)*
95                                 $($type => {
96                                         $field = Some(ser::Readable::read(&mut s)?);
97                                         if s.bytes_remain() {
98                                                 s.eat_remaining()?; // Return ShortRead if there's actually not enough bytes
99                                                 Err(DecodeError::InvalidValue)?
100                                         }
101                                 },)*
102                                 x if x % 2 == 0 => {
103                                         Err(DecodeError::UnknownRequiredFeature)?
104                                 },
105                                 _ => {},
106                         }
107                         s.eat_remaining()?;
108                 }
109                 // Make sure we got to each required type after we've read every TLV:
110                 $(if last_seen_type.is_none() || last_seen_type.unwrap() < $reqtype {
111                         Err(DecodeError::InvalidValue)?
112                 })*
113         } }
114 }
115
116 macro_rules! impl_writeable {
117         ($st:ident, $len: expr, {$($field:ident),*}) => {
118                 impl ::util::ser::Writeable for $st {
119                         fn write<W: ::util::ser::Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
120                                 if $len != 0 {
121                                         w.size_hint($len);
122                                 }
123                                 $( self.$field.write(w)?; )*
124                                 Ok(())
125                         }
126                 }
127
128                 impl ::util::ser::Readable for $st {
129                         fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, ::ln::msgs::DecodeError> {
130                                 Ok(Self {
131                                         $($field: ::util::ser::Readable::read(r)?),*
132                                 })
133                         }
134                 }
135         }
136 }
137 macro_rules! impl_writeable_len_match {
138         ($st:ident, {$({$m: pat, $l: expr}),*}, {$($field:ident),*}) => {
139                 impl Writeable for $st {
140                         fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
141                                 w.size_hint(match *self {
142                                         $($m => $l,)*
143                                 });
144                                 $( self.$field.write(w)?; )*
145                                 Ok(())
146                         }
147                 }
148
149                 impl ::util::ser::Readable for $st {
150                         fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
151                                 Ok(Self {
152                                         $($field: Readable::read(r)?),*
153                                 })
154                         }
155                 }
156         }
157 }
158
159 #[cfg(test)]
160 mod tests {
161         use std::io::{Cursor, Read};
162         use ln::msgs::DecodeError;
163         use util::ser::{Readable, Writeable, HighZeroBytesDroppedVarInt, VecWriter};
164         use bitcoin::secp256k1::PublicKey;
165
166         // The BOLT TLV test cases don't include any tests which use our "required-value" logic since
167         // the encoding layer in the BOLTs has no such concept, though it makes our macros easier to
168         // work with so they're baked into the decoder. Thus, we have a few additional tests below
169         fn tlv_reader(s: &[u8]) -> Result<(u64, u32, Option<u32>), DecodeError> {
170                 let mut s = Cursor::new(s);
171                 let mut a: u64 = 0;
172                 let mut b: u32 = 0;
173                 let mut c: Option<u32> = None;
174                 decode_tlv!(&mut s, {(2, a), (3, b)}, {(4, c)});
175                 Ok((a, b, c))
176         }
177
178         #[test]
179         fn tlv_v_short_read() {
180                 // We only expect a u32 for type 3 (which we are given), but the L says its 8 bytes.
181                 if let Err(DecodeError::ShortRead) = tlv_reader(&::hex::decode(
182                                 concat!("0100", "0208deadbeef1badbeef", "0308deadbeef")
183                                 ).unwrap()[..]) {
184                 } else { panic!(); }
185         }
186
187         #[test]
188         fn tlv_types_out_of_order() {
189                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
190                                 concat!("0100", "0304deadbeef", "0208deadbeef1badbeef")
191                                 ).unwrap()[..]) {
192                 } else { panic!(); }
193                 // ...even if its some field we don't understand
194                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
195                                 concat!("0208deadbeef1badbeef", "0100", "0304deadbeef")
196                                 ).unwrap()[..]) {
197                 } else { panic!(); }
198         }
199
200         #[test]
201         fn tlv_req_type_missing_or_extra() {
202                 // It's also bad if they included even fields we don't understand
203                 if let Err(DecodeError::UnknownRequiredFeature) = tlv_reader(&::hex::decode(
204                                 concat!("0100", "0208deadbeef1badbeef", "0304deadbeef", "0600")
205                                 ).unwrap()[..]) {
206                 } else { panic!(); }
207                 // ... or if they're missing fields we need
208                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
209                                 concat!("0100", "0208deadbeef1badbeef")
210                                 ).unwrap()[..]) {
211                 } else { panic!(); }
212                 // ... even if that field is even
213                 if let Err(DecodeError::InvalidValue) = tlv_reader(&::hex::decode(
214                                 concat!("0304deadbeef", "0500")
215                                 ).unwrap()[..]) {
216                 } else { panic!(); }
217         }
218
219         #[test]
220         fn tlv_simple_good_cases() {
221                 assert_eq!(tlv_reader(&::hex::decode(
222                                 concat!("0208deadbeef1badbeef", "03041bad1dea")
223                                 ).unwrap()[..]).unwrap(),
224                         (0xdeadbeef1badbeef, 0x1bad1dea, None));
225                 assert_eq!(tlv_reader(&::hex::decode(
226                                 concat!("0208deadbeef1badbeef", "03041bad1dea", "040401020304")
227                                 ).unwrap()[..]).unwrap(),
228                         (0xdeadbeef1badbeef, 0x1bad1dea, Some(0x01020304)));
229         }
230
231         impl Readable for (PublicKey, u64, u64) {
232                 #[inline]
233                 fn read<R: Read>(reader: &mut R) -> Result<(PublicKey, u64, u64), DecodeError> {
234                         Ok((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?))
235                 }
236         }
237
238         // BOLT TLV test cases
239         fn tlv_reader_n1(s: &[u8]) -> Result<(Option<HighZeroBytesDroppedVarInt<u64>>, Option<u64>, Option<(PublicKey, u64, u64)>, Option<u16>), DecodeError> {
240                 let mut s = Cursor::new(s);
241                 let mut tlv1: Option<HighZeroBytesDroppedVarInt<u64>> = None;
242                 let mut tlv2: Option<u64> = None;
243                 let mut tlv3: Option<(PublicKey, u64, u64)> = None;
244                 let mut tlv4: Option<u16> = None;
245                 decode_tlv!(&mut s, {}, {(1, tlv1), (2, tlv2), (3, tlv3), (254, tlv4)});
246                 Ok((tlv1, tlv2, tlv3, tlv4))
247         }
248
249         #[test]
250         fn bolt_tlv_bogus_stream() {
251                 macro_rules! do_test {
252                         ($stream: expr, $reason: ident) => {
253                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
254                                 } else { panic!(); }
255                         }
256                 }
257
258                 // TLVs from the BOLT test cases which should not decode as either n1 or n2
259                 do_test!(concat!("fd01"), ShortRead);
260                 do_test!(concat!("fd0001", "00"), InvalidValue);
261                 do_test!(concat!("fd0101"), ShortRead);
262                 do_test!(concat!("0f", "fd"), ShortRead);
263                 do_test!(concat!("0f", "fd26"), ShortRead);
264                 do_test!(concat!("0f", "fd2602"), ShortRead);
265                 do_test!(concat!("0f", "fd0001", "00"), InvalidValue);
266                 do_test!(concat!("0f", "fd0201", "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"), ShortRead);
267
268                 do_test!(concat!("12", "00"), UnknownRequiredFeature);
269                 do_test!(concat!("fd0102", "00"), UnknownRequiredFeature);
270                 do_test!(concat!("fe01000002", "00"), UnknownRequiredFeature);
271                 do_test!(concat!("ff0100000000000002", "00"), UnknownRequiredFeature);
272         }
273
274         #[test]
275         fn bolt_tlv_bogus_n1_stream() {
276                 macro_rules! do_test {
277                         ($stream: expr, $reason: ident) => {
278                                 if let Err(DecodeError::$reason) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
279                                 } else { panic!(); }
280                         }
281                 }
282
283                 // TLVs from the BOLT test cases which should not decode as n1
284                 do_test!(concat!("01", "09", "ffffffffffffffffff"), InvalidValue);
285                 do_test!(concat!("01", "01", "00"), InvalidValue);
286                 do_test!(concat!("01", "02", "0001"), InvalidValue);
287                 do_test!(concat!("01", "03", "000100"), InvalidValue);
288                 do_test!(concat!("01", "04", "00010000"), InvalidValue);
289                 do_test!(concat!("01", "05", "0001000000"), InvalidValue);
290                 do_test!(concat!("01", "06", "000100000000"), InvalidValue);
291                 do_test!(concat!("01", "07", "00010000000000"), InvalidValue);
292                 do_test!(concat!("01", "08", "0001000000000000"), InvalidValue);
293                 do_test!(concat!("02", "07", "01010101010101"), ShortRead);
294                 do_test!(concat!("02", "09", "010101010101010101"), InvalidValue);
295                 do_test!(concat!("03", "21", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb"), ShortRead);
296                 do_test!(concat!("03", "29", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001"), ShortRead);
297                 do_test!(concat!("03", "30", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb000000000000000100000000000001"), ShortRead);
298                 do_test!(concat!("03", "31", "043da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"), InvalidValue);
299                 do_test!(concat!("03", "32", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb0000000000000001000000000000000001"), InvalidValue);
300                 do_test!(concat!("fd00fe", "00"), ShortRead);
301                 do_test!(concat!("fd00fe", "01", "01"), ShortRead);
302                 do_test!(concat!("fd00fe", "03", "010101"), InvalidValue);
303                 do_test!(concat!("00", "00"), UnknownRequiredFeature);
304
305                 do_test!(concat!("02", "08", "0000000000000226", "01", "01", "2a"), InvalidValue);
306                 do_test!(concat!("02", "08", "0000000000000231", "02", "08", "0000000000000451"), InvalidValue);
307                 do_test!(concat!("1f", "00", "0f", "01", "2a"), InvalidValue);
308                 do_test!(concat!("1f", "00", "1f", "01", "2a"), InvalidValue);
309
310                 // The last BOLT test modified to not require creating a new decoder for one trivial test.
311                 do_test!(concat!("ffffffffffffffffff", "00", "01", "00"), InvalidValue);
312         }
313
314         #[test]
315         fn bolt_tlv_valid_n1_stream() {
316                 macro_rules! do_test {
317                         ($stream: expr, $tlv1: expr, $tlv2: expr, $tlv3: expr, $tlv4: expr) => {
318                                 if let Ok((tlv1, tlv2, tlv3, tlv4)) = tlv_reader_n1(&::hex::decode($stream).unwrap()[..]) {
319                                         assert_eq!(tlv1.map(|v| v.0), $tlv1);
320                                         assert_eq!(tlv2, $tlv2);
321                                         assert_eq!(tlv3, $tlv3);
322                                         assert_eq!(tlv4, $tlv4);
323                                 } else { panic!(); }
324                         }
325                 }
326
327                 do_test!(concat!(""), None, None, None, None);
328                 do_test!(concat!("21", "00"), None, None, None, None);
329                 do_test!(concat!("fd0201", "00"), None, None, None, None);
330                 do_test!(concat!("fd00fd", "00"), None, None, None, None);
331                 do_test!(concat!("fd00ff", "00"), None, None, None, None);
332                 do_test!(concat!("fe02000001", "00"), None, None, None, None);
333                 do_test!(concat!("ff0200000000000001", "00"), None, None, None, None);
334
335                 do_test!(concat!("01", "00"), Some(0), None, None, None);
336                 do_test!(concat!("01", "01", "01"), Some(1), None, None, None);
337                 do_test!(concat!("01", "02", "0100"), Some(256), None, None, None);
338                 do_test!(concat!("01", "03", "010000"), Some(65536), None, None, None);
339                 do_test!(concat!("01", "04", "01000000"), Some(16777216), None, None, None);
340                 do_test!(concat!("01", "05", "0100000000"), Some(4294967296), None, None, None);
341                 do_test!(concat!("01", "06", "010000000000"), Some(1099511627776), None, None, None);
342                 do_test!(concat!("01", "07", "01000000000000"), Some(281474976710656), None, None, None);
343                 do_test!(concat!("01", "08", "0100000000000000"), Some(72057594037927936), None, None, None);
344                 do_test!(concat!("02", "08", "0000000000000226"), None, Some((0 << 30) | (0 << 5) | (550 << 0)), None, None);
345                 do_test!(concat!("03", "31", "023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb00000000000000010000000000000002"),
346                         None, None, Some((
347                                 PublicKey::from_slice(&::hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]).unwrap(), 1, 2)),
348                         None);
349                 do_test!(concat!("fd00fe", "02", "0226"), None, None, None, Some(550));
350         }
351
352         fn do_simple_test_tlv_write() -> Result<(), ::std::io::Error> {
353                 let mut stream = VecWriter(Vec::new());
354
355                 stream.0.clear();
356                 encode_varint_length_prefixed_tlv!(&mut stream, { (1, 1u8) });
357                 assert_eq!(stream.0, ::hex::decode("03010101").unwrap());
358
359                 stream.0.clear();
360                 encode_varint_length_prefixed_tlv!(&mut stream, { (4, 0xabcdu16) });
361                 assert_eq!(stream.0, ::hex::decode("040402abcd").unwrap());
362
363                 stream.0.clear();
364                 encode_varint_length_prefixed_tlv!(&mut stream, { (0xff, 0xabcdu16) });
365                 assert_eq!(stream.0, ::hex::decode("06fd00ff02abcd").unwrap());
366
367                 stream.0.clear();
368                 encode_varint_length_prefixed_tlv!(&mut stream, { (0, 1u64), (0xff, HighZeroBytesDroppedVarInt(0u64)) });
369                 assert_eq!(stream.0, ::hex::decode("0e00080000000000000001fd00ff00").unwrap());
370
371                 Ok(())
372         }
373
374         #[test]
375         fn simple_test_tlv_write() {
376                 do_simple_test_tlv_write().unwrap();
377         }
378 }