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