fixup! feat(offers): add BOLT 12 payer proof primitives

fixup! feat(offers): add BOLT 12 payer proof primitives

Author: vincenzopalazzo

lightning/src/offers/payer_proof.rs

@@ -797,6 +797,12 @@ impl TryFrom<FullPayerProofTlvStream> for ParsedPayerProofFields {
 		let preimage = proof_preimage.ok_or(Bolt12ParseError::Decode(DecodeError::InvalidValue))?;
 		let proof_signature = proof_signature
 			.ok_or(Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSignature))?;
+		// Per BOLT 12 PR 1295, both `proof_missing_hashes` and `proof_leaf_hashes`
+		// TLVs MUST be present. `proof_omitted_markers` MAY be omitted when empty.
+		let missing_hashes =
+			proof_missing_hashes.ok_or(Bolt12ParseError::Decode(DecodeError::InvalidValue))?;
+		let leaf_hashes =
+			proof_leaf_hashes.ok_or(Bolt12ParseError::Decode(DecodeError::InvalidValue))?;
 
 		Ok(Self {
 			contents: PayerProofContents {
@@ -819,8 +825,8 @@ impl TryFrom<FullPayerProofTlvStream> for ParsedPayerProofFields {
 				.into_iter()
 				.map(|marker| marker.0)
 				.collect(),
-			missing_hashes: proof_missing_hashes.unwrap_or_default(),
-			leaf_hashes: proof_leaf_hashes.unwrap_or_default(),
+			missing_hashes,
+			leaf_hashes,
 		})
 	}
 }
@@ -1793,6 +1799,37 @@ mod tests {
 		assert!(result.is_err(), "payer_signature with len < 64 should be rejected");
 	}
 
+	/// Helper: serialize a payer_proof's bytes minus any TLV record matching `drop_type`.
+	fn proof_bytes_without_tlv(proof: &PayerProof, drop_type: u64) -> Vec<u8> {
+		let mut out = Vec::new();
+		for record in TlvStream::new(proof.bytes()) {
+			if record.r#type != drop_type {
+				out.extend_from_slice(record.record_bytes);
+			}
+		}
+		out
+	}
+
+	/// Per BOLT 12 PR 1295: the reader MUST reject a payer_proof if `proof_missing_hashes`
+	/// (TLV 1003) is missing.
+	#[test]
+	fn test_parsing_rejects_missing_proof_missing_hashes() {
+		let proof = build_round_trip_proof_with_disclosed_fields();
+		let stripped = proof_bytes_without_tlv(&proof, PAYER_PROOF_MISSING_HASHES_TYPE);
+		let result = PayerProof::try_from(stripped);
+		assert!(result.is_err(), "missing proof_missing_hashes TLV must be rejected");
+	}
+
+	/// Per BOLT 12 PR 1295: the reader MUST reject a payer_proof if `proof_leaf_hashes`
+	/// (TLV 1004) is missing.
+	#[test]
+	fn test_parsing_rejects_missing_proof_leaf_hashes() {
+		let proof = build_round_trip_proof_with_disclosed_fields();
+		let stripped = proof_bytes_without_tlv(&proof, PAYER_PROOF_LEAF_HASHES_TYPE);
+		let result = PayerProof::try_from(stripped);
+		assert!(result.is_err(), "missing proof_leaf_hashes TLV must be rejected");
+	}
+
 	#[test]
 	fn test_round_trip_with_trailing_experimental_tlvs() {
 		use core::convert::TryFrom;