Use TaggedHash in merkle::verify_signature

An earlier commit introduced TaggedHash for use in sign_message. For
consistency, use it in verify_signature, too.

diff --git a/lightning/src/offers/invoice.rs b/lightning/src/offers/invoice.rs
index 05960642efd111e2f748a805ab2df628e1d24682..745b389fa4673d34141aa8d42a017594e64c8cdc 100644 (file)
--- a/lightning/src/offers/invoice.rs
+++ b/lightning/src/offers/invoice.rs
@@ -1184,8 +1184,9 @@ impl TryFrom<ParsedMessage<FullInvoiceTlvStream>> for Bolt12Invoice {
                        None => return Err(Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSignature)),
                        Some(signature) => signature,
                };
+               let message = TaggedHash::new(SIGNATURE_TAG, &bytes);
                let pubkey = contents.fields().signing_pubkey;
-               merkle::verify_signature(&signature, SIGNATURE_TAG, &bytes, pubkey)?;
+               merkle::verify_signature(&signature, message, pubkey)?;
 
                Ok(Bolt12Invoice { bytes, contents, signature })
        }
@@ -1288,7 +1289,7 @@ mod tests {
        use crate::ln::inbound_payment::ExpandedKey;
        use crate::ln::msgs::DecodeError;
        use crate::offers::invoice_request::InvoiceRequestTlvStreamRef;
-       use crate::offers::merkle::{SignError, SignatureTlvStreamRef, self};
+       use crate::offers::merkle::{SignError, SignatureTlvStreamRef, TaggedHash, self};
        use crate::offers::offer::{Amount, OfferBuilder, OfferTlvStreamRef, Quantity};
        use crate::offers::parse::{Bolt12ParseError, Bolt12SemanticError};
        use crate::offers::payer::PayerTlvStreamRef;
@@ -1400,11 +1401,9 @@ mod tests {
                assert_eq!(invoice.fallbacks(), vec![]);
                assert_eq!(invoice.invoice_features(), &Bolt12InvoiceFeatures::empty());
                assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
-               assert!(
-                       merkle::verify_signature(
-                               &invoice.signature, SIGNATURE_TAG, &invoice.bytes, recipient_pubkey()
-                       ).is_ok()
-               );
+
+               let message = TaggedHash::new(SIGNATURE_TAG, &invoice.bytes);
+               assert!(merkle::verify_signature(&invoice.signature, message, recipient_pubkey()).is_ok());
 
                let digest = Message::from_slice(&invoice.signable_hash()).unwrap();
                let pubkey = recipient_pubkey().into();
@@ -1499,11 +1498,9 @@ mod tests {
                assert_eq!(invoice.fallbacks(), vec![]);
                assert_eq!(invoice.invoice_features(), &Bolt12InvoiceFeatures::empty());
                assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
-               assert!(
-                       merkle::verify_signature(
-                               &invoice.signature, SIGNATURE_TAG, &invoice.bytes, recipient_pubkey()
-                       ).is_ok()
-               );
+
+               let message = TaggedHash::new(SIGNATURE_TAG, &invoice.bytes);
+               assert!(merkle::verify_signature(&invoice.signature, message, recipient_pubkey()).is_ok());
 
                assert_eq!(
                        invoice.as_tlv_stream(),

diff --git a/lightning/src/offers/invoice_request.rs b/lightning/src/offers/invoice_request.rs
index 198e15ec527905e064747dec01a443f9375a3b33..41c86171b1bf31be953cdb1d9288ced33fe03413 100644 (file)
--- a/lightning/src/offers/invoice_request.rs
+++ b/lightning/src/offers/invoice_request.rs
@@ -799,7 +799,8 @@ impl TryFrom<Vec<u8>> for InvoiceRequest {
                        None => return Err(Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSignature)),
                        Some(signature) => signature,
                };
-               merkle::verify_signature(&signature, SIGNATURE_TAG, &bytes, contents.payer_id)?;
+               let message = TaggedHash::new(SIGNATURE_TAG, &bytes);
+               merkle::verify_signature(&signature, message, contents.payer_id)?;
 
                Ok(InvoiceRequest { bytes, contents, signature })
        }
@@ -933,11 +934,9 @@ mod tests {
                assert_eq!(invoice_request.quantity(), None);
                assert_eq!(invoice_request.payer_id(), payer_pubkey());
                assert_eq!(invoice_request.payer_note(), None);
-               assert!(
-                       merkle::verify_signature(
-                               &invoice_request.signature, SIGNATURE_TAG, &invoice_request.bytes, payer_pubkey()
-                       ).is_ok()
-               );
+
+               let message = TaggedHash::new(SIGNATURE_TAG, &invoice_request.bytes);
+               assert!(merkle::verify_signature(&invoice_request.signature, message, payer_pubkey()).is_ok());
 
                assert_eq!(
                        invoice_request.as_tlv_stream(),

diff --git a/lightning/src/offers/merkle.rs b/lightning/src/offers/merkle.rs
index b3867bf6f65a0d55d2b6969e32172f0919618249..7390b58fef8ef780a68f58aa50438dcbe1979d71 100644 (file)
--- a/lightning/src/offers/merkle.rs
+++ b/lightning/src/offers/merkle.rs
@@ -88,17 +88,15 @@ where
        Ok(signature)
 }
 
-/// Verifies the signature with a pubkey over the given bytes using a tagged hash as the message
+/// Verifies the signature with a pubkey over the given message using a tagged hash as the message
 /// digest.
-///
-/// Panics if `bytes` is not a well-formed TLV stream containing at least one TLV record.
 pub(super) fn verify_signature(
-       signature: &Signature, tag: &str, bytes: &[u8], pubkey: PublicKey,
+       signature: &Signature, message: TaggedHash, pubkey: PublicKey,
 ) -> Result<(), secp256k1::Error> {
-       let digest = message_digest(tag, bytes);
+       let digest = message.as_digest();
        let pubkey = pubkey.into();
        let secp_ctx = Secp256k1::verification_only();
-       secp_ctx.verify_schnorr(signature, &digest, &pubkey)
+       secp_ctx.verify_schnorr(signature, digest, &pubkey)
 }
 
 pub(super) fn message_digest(tag: &str, bytes: &[u8]) -> Message {