_ Git - rust-lightning/blob - lightning/src/offers/parse.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 //! Parsing and formatting for bech32 message encoding.
  11
  12 use bitcoin::bech32;
  13 use bitcoin::secp256k1;
  14 use core::convert::TryFrom;
  15 use crate::io;
  16 use crate::ln::msgs::DecodeError;
  17 use crate::util::ser::SeekReadable;
  18
  19 #[allow(unused_imports)]
  20 use crate::prelude::*;
  21
  22 #[cfg(not(fuzzing))]
  23 pub(super) use sealed::Bech32Encode;
  24
  25 #[cfg(fuzzing)]
  26 pub use sealed::Bech32Encode;
  27
  28 mod sealed {
  29         use bitcoin::bech32;
  30         use bitcoin::bech32::{FromBase32, ToBase32};
  31         use core::convert::TryFrom;
  32         use core::fmt;
  33         use super::Bolt12ParseError;
  34
  35         #[allow(unused_imports)]
  36         use crate::prelude::*;
  37
  38         /// Indicates a message can be encoded using bech32.
  39         pub trait Bech32Encode: AsRef<[u8]> + TryFrom<Vec<u8>, Error=Bolt12ParseError> {
  40                 /// Human readable part of the message's bech32 encoding.
  41                 const BECH32_HRP: &'static str;
  42
  43                 /// Parses a bech32-encoded message into a TLV stream.
  44                 fn from_bech32_str(s: &str) -> Result<Self, Bolt12ParseError> {
  45                         // Offer encoding may be split by '+' followed by optional whitespace.
  46                         let encoded = match s.split('+').skip(1).next() {
  47                                 Some(_) => {
  48                                         for chunk in s.split('+') {
  49                                                 let chunk = chunk.trim_start();
  50                                                 if chunk.is_empty() || chunk.contains(char::is_whitespace) {
  51                                                         return Err(Bolt12ParseError::InvalidContinuation);
  52                                                 }
  53                                         }
  54
  55                                         let s: String = s.chars().filter(|c| *c != '+' && !c.is_whitespace()).collect();
  56                                         Bech32String::Owned(s)
  57                                 },
  58                                 None => Bech32String::Borrowed(s),
  59                         };
  60
  61                         let (hrp, data) = bech32::decode_without_checksum(encoded.as_ref())?;
  62
  63                         if hrp != Self::BECH32_HRP {
  64                                 return Err(Bolt12ParseError::InvalidBech32Hrp);
  65                         }
  66
  67                         let data = Vec::<u8>::from_base32(&data)?;
  68                         Self::try_from(data)
  69                 }
  70
  71                 /// Formats the message using bech32-encoding.
  72                 fn fmt_bech32_str(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
  73                         bech32::encode_without_checksum_to_fmt(f, Self::BECH32_HRP, self.as_ref().to_base32())
  74                                 .expect("HRP is invalid").unwrap();
  75
  76                         Ok(())
  77                 }
  78         }
  79
  80         // Used to avoid copying a bech32 string not containing the continuation character (+).
  81         enum Bech32String<'a> {
  82                 Borrowed(&'a str),
  83                 Owned(String),
  84         }
  85
  86         impl<'a> AsRef<str> for Bech32String<'a> {
  87                 fn as_ref(&self) -> &str {
  88                         match self {
  89                                 Bech32String::Borrowed(s) => s,
  90                                 Bech32String::Owned(s) => s,
  91                         }
  92                 }
  93         }
  94 }
  95
  96 /// A wrapper for reading a message as a TLV stream `T` from a byte sequence, while still
  97 /// maintaining ownership of the bytes for later use.
  98 pub(super) struct ParsedMessage<T: SeekReadable> {
  99         pub bytes: Vec<u8>,
 100         pub tlv_stream: T,
 101 }
 102
 103 impl<T: SeekReadable> TryFrom<Vec<u8>> for ParsedMessage<T> {
 104         type Error = DecodeError;
 105
 106         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
 107                 let mut cursor = io::Cursor::new(bytes);
 108                 let tlv_stream: T = SeekReadable::read(&mut cursor)?;
 109
 110                 // Ensure that there are no more TLV records left to parse.
 111                 if cursor.position() < cursor.get_ref().len() as u64 {
 112                         return Err(DecodeError::InvalidValue);
 113                 }
 114
 115                 let bytes = cursor.into_inner();
 116                 Ok(Self { bytes, tlv_stream })
 117         }
 118 }
 119
 120 /// Error when parsing a bech32 encoded message using [`str::parse`].
 121 #[derive(Clone, Debug, PartialEq)]
 122 pub enum Bolt12ParseError {
 123         /// The bech32 encoding does not conform to the BOLT 12 requirements for continuing messages
 124         /// across multiple parts (i.e., '+' followed by whitespace).
 125         InvalidContinuation,
 126         /// The bech32 encoding's human-readable part does not match what was expected for the message
 127         /// being parsed.
 128         InvalidBech32Hrp,
 129         /// The string could not be bech32 decoded.
 130         Bech32(bech32::Error),
 131         /// The bech32 decoded string could not be decoded as the expected message type.
 132         Decode(DecodeError),
 133         /// The parsed message has invalid semantics.
 134         InvalidSemantics(Bolt12SemanticError),
 135         /// The parsed message has an invalid signature.
 136         InvalidSignature(secp256k1::Error),
 137 }
 138
 139 /// Error when interpreting a TLV stream as a specific type.
 140 #[derive(Clone, Debug, PartialEq)]
 141 pub enum Bolt12SemanticError {
 142         /// The current [`std::time::SystemTime`] is past the offer or invoice's expiration.
 143         AlreadyExpired,
 144         /// The provided chain hash does not correspond to a supported chain.
 145         UnsupportedChain,
 146         /// A chain was provided but was not expected.
 147         UnexpectedChain,
 148         /// An amount was expected but was missing.
 149         MissingAmount,
 150         /// The amount exceeded the total bitcoin supply.
 151         InvalidAmount,
 152         /// An amount was provided but was not sufficient in value.
 153         InsufficientAmount,
 154         /// An amount was provided but was not expected.
 155         UnexpectedAmount,
 156         /// A currency was provided that is not supported.
 157         UnsupportedCurrency,
 158         /// A feature was required but is unknown.
 159         UnknownRequiredFeatures,
 160         /// Features were provided but were not expected.
 161         UnexpectedFeatures,
 162         /// A required description was not provided.
 163         MissingDescription,
 164         /// A signing pubkey was not provided.
 165         MissingSigningPubkey,
 166         /// A signing pubkey was provided but a different one was expected.
 167         InvalidSigningPubkey,
 168         /// A signing pubkey was provided but was not expected.
 169         UnexpectedSigningPubkey,
 170         /// A quantity was expected but was missing.
 171         MissingQuantity,
 172         /// An unsupported quantity was provided.
 173         InvalidQuantity,
 174         /// A quantity or quantity bounds was provided but was not expected.
 175         UnexpectedQuantity,
 176         /// Metadata could not be used to verify the offers message.
 177         InvalidMetadata,
 178         /// Metadata was provided but was not expected.
 179         UnexpectedMetadata,
 180         /// Payer metadata was expected but was missing.
 181         MissingPayerMetadata,
 182         /// A payer id was expected but was missing.
 183         MissingPayerId,
 184         /// The payment id for a refund or request is already in use.
 185         DuplicatePaymentId,
 186         /// Blinded paths were expected but were missing.
 187         MissingPaths,
 188         /// The blinded payinfo given does not match the number of blinded path hops.
 189         InvalidPayInfo,
 190         /// An invoice creation time was expected but was missing.
 191         MissingCreationTime,
 192         /// An invoice payment hash was expected but was missing.
 193         MissingPaymentHash,
 194         /// A signature was expected but was missing.
 195         MissingSignature,
 196 }
 197
 198 impl From<bech32::Error> for Bolt12ParseError {
 199         fn from(error: bech32::Error) -> Self {
 200                 Self::Bech32(error)
 201         }
 202 }
 203
 204 impl From<DecodeError> for Bolt12ParseError {
 205         fn from(error: DecodeError) -> Self {
 206                 Self::Decode(error)
 207         }
 208 }
 209
 210 impl From<Bolt12SemanticError> for Bolt12ParseError {
 211         fn from(error: Bolt12SemanticError) -> Self {
 212                 Self::InvalidSemantics(error)
 213         }
 214 }
 215
 216 impl From<secp256k1::Error> for Bolt12ParseError {
 217         fn from(error: secp256k1::Error) -> Self {
 218                 Self::InvalidSignature(error)
 219         }
 220 }
 221
 222 #[cfg(test)]
 223 mod bolt12_tests {
 224         use super::Bolt12ParseError;
 225         use crate::offers::offer::Offer;
 226
 227         #[test]
 228         fn encodes_offer_as_bech32_without_checksum() {
 229                 let encoded_offer = "lno1pqps7sjqpgtyzm3qv4uxzmtsd3jjqer9wd3hy6tsw35k7msjzfpy7nz5yqcnygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd5xvxg";
 230                 let offer = dbg!(encoded_offer.parse::<Offer>().unwrap());
 231                 let reencoded_offer = offer.to_string();
 232                 dbg!(reencoded_offer.parse::<Offer>().unwrap());
 233                 assert_eq!(reencoded_offer, encoded_offer);
 234         }
 235
 236         #[test]
 237         fn parses_bech32_encoded_offers() {
 238                 let offers = [
 239                         // A complete string is valid
 240                         "lno1pqps7sjqpgtyzm3qv4uxzmtsd3jjqer9wd3hy6tsw35k7msjzfpy7nz5yqcnygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd5xvxg",
 241
 242                         // + can join anywhere
 243                         "l+no1pqps7sjqpgtyzm3qv4uxzmtsd3jjqer9wd3hy6tsw35k7msjzfpy7nz5yqcnygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd5xvxg",
 244
 245                         // Multiple + can join
 246                         "lno1pqps7sjqpgt+yzm3qv4uxzmtsd3jjqer9wd3hy6tsw3+5k7msjzfpy7nz5yqcn+ygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd+5xvxg",
 247
 248                         // + can be followed by whitespace
 249                         "lno1pqps7sjqpgt+ yzm3qv4uxzmtsd3jjqer9wd3hy6tsw3+  5k7msjzfpy7nz5yqcn+\nygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd+\r\n 5xvxg",
 250                 ];
 251                 for encoded_offer in &offers {
 252                         if let Err(e) = encoded_offer.parse::<Offer>() {
 253                                 panic!("Invalid offer ({:?}): {}", e, encoded_offer);
 254                         }
 255                 }
 256         }
 257
 258         #[test]
 259         fn fails_parsing_bech32_encoded_offers_with_invalid_continuations() {
 260                 let offers = [
 261                         // + must be surrounded by bech32 characters
 262                         "lno1pqps7sjqpgtyzm3qv4uxzmtsd3jjqer9wd3hy6tsw35k7msjzfpy7nz5yqcnygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd5xvxg+",
 263                         "lno1pqps7sjqpgtyzm3qv4uxzmtsd3jjqer9wd3hy6tsw35k7msjzfpy7nz5yqcnygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd5xvxg+ ",
 264                         "+lno1pqps7sjqpgtyzm3qv4uxzmtsd3jjqer9wd3hy6tsw35k7msjzfpy7nz5yqcnygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd5xvxg",
 265                         "+ lno1pqps7sjqpgtyzm3qv4uxzmtsd3jjqer9wd3hy6tsw35k7msjzfpy7nz5yqcnygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd5xvxg",
 266                         "ln++o1pqps7sjqpgtyzm3qv4uxzmtsd3jjqer9wd3hy6tsw35k7msjzfpy7nz5yqcnygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd5xvxg",
 267                 ];
 268                 for encoded_offer in &offers {
 269                         match encoded_offer.parse::<Offer>() {
 270                                 Ok(_) => panic!("Valid offer: {}", encoded_offer),
 271                                 Err(e) => assert_eq!(e, Bolt12ParseError::InvalidContinuation),
 272                         }
 273                 }
 274         }
 275 }
 276
 277 #[cfg(test)]
 278 mod tests {
 279         use super::Bolt12ParseError;
 280         use bitcoin::bech32;
 281         use crate::ln::msgs::DecodeError;
 282         use crate::offers::offer::Offer;
 283
 284         #[test]
 285         fn fails_parsing_bech32_encoded_offer_with_invalid_hrp() {
 286                 let encoded_offer = "lni1pqps7sjqpgtyzm3qv4uxzmtsd3jjqer9wd3hy6tsw35k7msjzfpy7nz5yqcnygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd5xvxg";
 287                 match encoded_offer.parse::<Offer>() {
 288                         Ok(_) => panic!("Valid offer: {}", encoded_offer),
 289                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidBech32Hrp),
 290                 }
 291         }
 292
 293         #[test]
 294         fn fails_parsing_bech32_encoded_offer_with_invalid_bech32_data() {
 295                 let encoded_offer = "lno1pqps7sjqpgtyzm3qv4uxzmtsd3jjqer9wd3hy6tsw35k7msjzfpy7nz5yqcnygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd5xvxo";
 296                 match encoded_offer.parse::<Offer>() {
 297                         Ok(_) => panic!("Valid offer: {}", encoded_offer),
 298                         Err(e) => assert_eq!(e, Bolt12ParseError::Bech32(bech32::Error::InvalidChar('o'))),
 299                 }
 300         }
 301
 302         #[test]
 303         fn fails_parsing_bech32_encoded_offer_with_invalid_tlv_data() {
 304                 let encoded_offer = "lno1pqps7sjqpgtyzm3qv4uxzmtsd3jjqer9wd3hy6tsw35k7msjzfpy7nz5yqcnygrfdej82um5wf5k2uckyypwa3eyt44h6txtxquqh7lz5djge4afgfjn7k4rgrkuag0jsd5xvxgqqqqq";
 305                 match encoded_offer.parse::<Offer>() {
 306                         Ok(_) => panic!("Valid offer: {}", encoded_offer),
 307                         Err(e) => assert_eq!(e, Bolt12ParseError::Decode(DecodeError::InvalidValue)),
 308                 }
 309         }
 310 }