use bitcoin::secp256k1::{Message, PublicKey, Secp256k1, self};
use bitcoin::secp256k1::schnorr::Signature;
use crate::io;
-use crate::util::ser::{BigSize, Readable};
+use crate::util::ser::{BigSize, Readable, Writeable, Writer};
use crate::prelude::*;
secp_ctx.verify_schnorr(signature, &digest, &pubkey)
}
-fn message_digest(tag: &str, bytes: &[u8]) -> Message {
+pub(super) fn message_digest(tag: &str, bytes: &[u8]) -> Message {
let tag = sha256::Hash::hash(tag.as_bytes());
let merkle_root = root_hash(bytes);
Message::from_slice(&tagged_hash(tag, merkle_root)).unwrap()
/// Computes a merkle root hash for the given data, which must be a well-formed TLV stream
/// containing at least one TLV record.
fn root_hash(data: &[u8]) -> sha256::Hash {
- let mut tlv_stream = TlvStream::new(&data[..]).peekable();
let nonce_tag = tagged_hash_engine(sha256::Hash::from_engine({
+ let first_tlv_record = TlvStream::new(&data[..]).next().unwrap();
let mut engine = sha256::Hash::engine();
engine.input("LnNonce".as_bytes());
- engine.input(tlv_stream.peek().unwrap().record_bytes);
+ engine.input(first_tlv_record.record_bytes);
engine
}));
let leaf_tag = tagged_hash_engine(sha256::Hash::hash("LnLeaf".as_bytes()));
let branch_tag = tagged_hash_engine(sha256::Hash::hash("LnBranch".as_bytes()));
let mut leaves = Vec::new();
- for record in tlv_stream {
- if !SIGNATURE_TYPES.contains(&record.r#type) {
- leaves.push(tagged_hash_from_engine(leaf_tag.clone(), &record));
- leaves.push(tagged_hash_from_engine(nonce_tag.clone(), &record.type_bytes));
- }
+ let tlv_stream = TlvStream::new(&data[..]);
+ for record in tlv_stream.skip_signatures() {
+ leaves.push(tagged_hash_from_engine(leaf_tag.clone(), &record.record_bytes));
+ leaves.push(tagged_hash_from_engine(nonce_tag.clone(), &record.type_bytes));
}
// Calculate the merkle root hash in place.
/// [`Iterator`] over a sequence of bytes yielding [`TlvRecord`]s. The input is assumed to be a
/// well-formed TLV stream.
-struct TlvStream<'a> {
+#[derive(Clone)]
+pub(super) struct TlvStream<'a> {
data: io::Cursor<&'a [u8]>,
}
impl<'a> TlvStream<'a> {
- fn new(data: &'a [u8]) -> Self {
+ pub fn new(data: &'a [u8]) -> Self {
Self {
data: io::Cursor::new(data),
}
}
+
+ pub fn range<T>(self, types: T) -> impl core::iter::Iterator<Item = TlvRecord<'a>>
+ where
+ T: core::ops::RangeBounds<u64> + Clone,
+ {
+ let take_range = types.clone();
+ self.skip_while(move |record| !types.contains(&record.r#type))
+ .take_while(move |record| take_range.contains(&record.r#type))
+ }
+
+ fn skip_signatures(self) -> core::iter::Filter<TlvStream<'a>, fn(&TlvRecord) -> bool> {
+ self.filter(|record| !SIGNATURE_TYPES.contains(&record.r#type))
+ }
}
/// A slice into a [`TlvStream`] for a record.
-struct TlvRecord<'a> {
- r#type: u64,
+pub(super) struct TlvRecord<'a> {
+ pub(super) r#type: u64,
type_bytes: &'a [u8],
// The entire TLV record.
- record_bytes: &'a [u8],
-}
-
-impl AsRef<[u8]> for TlvRecord<'_> {
- fn as_ref(&self) -> &[u8] { &self.record_bytes }
+ pub(super) record_bytes: &'a [u8],
}
impl<'a> Iterator for TlvStream<'a> {
}
}
+/// Encoding for a pre-serialized TLV stream that excludes any signature TLV records.
+///
+/// Panics if the wrapped bytes are not a well-formed TLV stream.
+pub(super) struct WithoutSignatures<'a>(pub &'a Vec<u8>);
+
+impl<'a> Writeable for WithoutSignatures<'a> {
+ #[inline]
+ fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
+ let tlv_stream = TlvStream::new(&self.0[..]);
+ for record in tlv_stream.skip_signatures() {
+ writer.write_all(record.record_bytes)?;
+ }
+ Ok(())
+ }
+}
+
#[cfg(test)]
mod tests {
+ use super::{SIGNATURE_TYPES, TlvStream, WithoutSignatures};
+
use bitcoin::hashes::{Hash, sha256};
use bitcoin::secp256k1::{KeyPair, Secp256k1, SecretKey};
+ use bitcoin::secp256k1::schnorr::Signature;
use core::convert::Infallible;
use crate::offers::offer::{Amount, OfferBuilder};
use crate::offers::invoice_request::InvoiceRequest;
use crate::offers::parse::Bech32Encode;
+ use crate::util::ser::Writeable;
#[test]
fn calculates_merkle_root_hash() {
super::root_hash(&invoice_request.bytes[..]),
sha256::Hash::from_slice(&hex::decode("608407c18ad9a94d9ea2bcdbe170b6c20c462a7833a197621c916f78cf18e624").unwrap()).unwrap(),
);
+ assert_eq!(
+ invoice_request.signature(),
+ Signature::from_slice(&hex::decode("b8f83ea3288cfd6ea510cdb481472575141e8d8744157f98562d162cc1c472526fdb24befefbdebab4dbb726bbd1b7d8aec057f8fa805187e5950d2bbe0e5642").unwrap()).unwrap(),
+ );
+ }
+
+ #[test]
+ fn skips_encoding_signature_tlv_records() {
+ let secp_ctx = Secp256k1::new();
+ let recipient_pubkey = {
+ let secret_key = SecretKey::from_slice(&[41; 32]).unwrap();
+ KeyPair::from_secret_key(&secp_ctx, &secret_key).public_key()
+ };
+ let payer_keys = {
+ let secret_key = SecretKey::from_slice(&[42; 32]).unwrap();
+ KeyPair::from_secret_key(&secp_ctx, &secret_key)
+ };
+
+ let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey)
+ .amount_msats(100)
+ .build_unchecked()
+ .request_invoice(vec![0; 8], payer_keys.public_key()).unwrap()
+ .build_unchecked()
+ .sign::<_, Infallible>(|digest| Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &payer_keys)))
+ .unwrap();
+
+ let mut bytes_without_signature = Vec::new();
+ WithoutSignatures(&invoice_request.bytes).write(&mut bytes_without_signature).unwrap();
+
+ assert_ne!(bytes_without_signature, invoice_request.bytes);
+ assert_eq!(
+ TlvStream::new(&bytes_without_signature).count(),
+ TlvStream::new(&invoice_request.bytes).count() - 1,
+ );
+ }
+
+ #[test]
+ fn iterates_over_tlv_stream_range() {
+ let secp_ctx = Secp256k1::new();
+ let recipient_pubkey = {
+ let secret_key = SecretKey::from_slice(&[41; 32]).unwrap();
+ KeyPair::from_secret_key(&secp_ctx, &secret_key).public_key()
+ };
+ let payer_keys = {
+ let secret_key = SecretKey::from_slice(&[42; 32]).unwrap();
+ KeyPair::from_secret_key(&secp_ctx, &secret_key)
+ };
+
+ let invoice_request = OfferBuilder::new("foo".into(), recipient_pubkey)
+ .amount_msats(100)
+ .build_unchecked()
+ .request_invoice(vec![0; 8], payer_keys.public_key()).unwrap()
+ .build_unchecked()
+ .sign::<_, Infallible>(|digest| Ok(secp_ctx.sign_schnorr_no_aux_rand(digest, &payer_keys)))
+ .unwrap();
+
+ let tlv_stream = TlvStream::new(&invoice_request.bytes).range(0..1)
+ .chain(TlvStream::new(&invoice_request.bytes).range(1..80))
+ .chain(TlvStream::new(&invoice_request.bytes).range(80..160))
+ .chain(TlvStream::new(&invoice_request.bytes).range(160..240))
+ .chain(TlvStream::new(&invoice_request.bytes).range(SIGNATURE_TYPES))
+ .map(|r| r.record_bytes.to_vec())
+ .flatten()
+ .collect::<Vec<u8>>();
+
+ assert_eq!(tlv_stream, invoice_request.bytes);
}
impl AsRef<[u8]> for InvoiceRequest {