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

Author: vincenzopalazzo

lightning/src/offers/payer_proof.rs

@@ -1013,6 +1013,12 @@ mod tests {
 		bytes.extend_from_slice(value_bytes);
 	}
 
+	/// Builds a proof whose underlying invoice carries a synthetic experimental TLV
+	/// at type [`EXPERIMENTAL_TEST_TLV_TYPE`] (`1_000_000_001`). Constructed by
+	/// hand because the public `RefundBuilder` API doesn't expose a way to write
+	/// arbitrary experimental TLV types — the existing `experimental_foo` family
+	/// of methods uses fixed type numbers that wouldn't exercise the same code
+	/// path.
 	fn build_round_trip_proof_with_included_experimental_tlv() -> PayerProof {
 		let secp_ctx = Secp256k1::new();
 
@@ -1084,6 +1090,12 @@ mod tests {
 			.unwrap()
 	}
 
+	/// Builds a proof with two consecutive *trailing* omitted experimental TLVs at
+	/// types `1_000_000_001` and `1_000_000_003`. The exact layout is load-bearing
+	/// for the `omitted_markers == [177, 178]` assertion on the parsed proof, and
+	/// the public `RefundBuilder` API doesn't expose a way to produce that exact
+	/// pair of trailing experimental types — so this helper writes the invoice
+	/// bytes by hand.
 	fn build_round_trip_proof_with_multiple_trailing_omitted_tlvs() -> PayerProof {
 		let secp_ctx = Secp256k1::new();
 
@@ -1150,83 +1162,38 @@ mod tests {
 	}
 
 	fn build_round_trip_proof_with_disclosed_fields() -> PayerProof {
-		let secp_ctx = Secp256k1::new();
-
-		let payer_secret = SecretKey::from_slice(&[62; 32]).unwrap();
-		let payer_keys = Keypair::from_secret_key(&secp_ctx, &payer_secret);
-		let payer_signing_pubkey = payer_keys.public_key();
-
-		let issuer_secret = SecretKey::from_slice(&[63; 32]).unwrap();
-		let issuer_keys = Keypair::from_secret_key(&secp_ctx, &issuer_secret);
-		let issuer_signing_pubkey = issuer_keys.public_key();
-
 		let preimage = PaymentPreimage([64; 32]);
-		let payment_hash = PaymentHash(sha256::Hash::hash(&preimage.0).to_byte_array());
-
-		let mut invoice_bytes = Vec::new();
-		write_tlv_record_bytes(&mut invoice_bytes, PAYER_METADATA_TYPE, &[65; 32]);
-		write_tlv_record_bytes(&mut invoice_bytes, OFFER_DESCRIPTION_TYPE, b"coffee beans");
-		write_tlv_record_bytes(&mut invoice_bytes, OFFER_ISSUER_TYPE, b"LDK Roastery");
-		write_tlv_record(&mut invoice_bytes, INVOICE_REQUEST_PAYER_ID_TYPE, &payer_signing_pubkey);
-		write_tlv_record(
-			&mut invoice_bytes,
-			INVOICE_CREATED_AT_TYPE,
-			&HighZeroBytesDroppedBigSize(1_700_000_000u64),
-		);
-		write_tlv_record(&mut invoice_bytes, INVOICE_PAYMENT_HASH_TYPE, &payment_hash);
-		write_tlv_record(
-			&mut invoice_bytes,
-			INVOICE_AMOUNT_TYPE,
-			&HighZeroBytesDroppedBigSize(42_000u64),
-		);
-		write_tlv_record(&mut invoice_bytes, INVOICE_NODE_ID_TYPE, &issuer_signing_pubkey);
-
-		let invoice_message =
-			TaggedHash::from_valid_tlv_stream_bytes(SIGNATURE_TAG, &invoice_bytes);
-		let invoice_signature =
-			secp_ctx.sign_schnorr_no_aux_rand(invoice_message.as_digest(), &issuer_keys);
-
-		let included_types: BTreeSet<u64> = [
-			OFFER_DESCRIPTION_TYPE,
-			OFFER_ISSUER_TYPE,
-			INVOICE_REQUEST_PAYER_ID_TYPE,
-			INVOICE_CREATED_AT_TYPE,
-			INVOICE_PAYMENT_HASH_TYPE,
-			INVOICE_AMOUNT_TYPE,
-			INVOICE_NODE_ID_TYPE,
-		]
-		.into_iter()
-		.collect();
-		let disclosed_fields = DisclosedFields::from_records(
-			TlvStream::new(&invoice_bytes).filter(|r| included_types.contains(&r.r#type)),
-		)
-		.unwrap();
-		let disclosure =
-			compute_selective_disclosure(TlvStream::new(&invoice_bytes), &included_types).unwrap();
-
-		let mut unsigned = UnsignedPayerProof {
-			invoice_signature,
-			preimage,
-			payer_signing_pubkey,
-			payment_hash,
-			issuer_signing_pubkey,
-			invoice_bytes: &invoice_bytes,
-			included_types,
-			disclosed_fields,
-			tagged_hash: TaggedHash::from_merkle_root(
-				PROOF_SIGNATURE_TAG,
-				sha256::Hash::all_zeros(),
-			),
-			disclosure,
-			proof_note: None,
-		};
-		let bytes_for_signing = unsigned.serialize_payer_proof(None);
-		unsigned.tagged_hash = proof_signature_hash(&bytes_for_signing);
+		let payment_hash = PaymentHash(*sha256::Hash::hash(&preimage.0).as_byte_array());
+		let invoice = RefundBuilder::new(vec![1; 32], payer_pubkey(), 42_000)
+			.unwrap()
+			.description("coffee beans".into())
+			.issuer("LDK Roastery".into())
+			.build()
+			.unwrap()
+			.respond_with_no_std(
+				payment_paths(),
+				payment_hash,
+				recipient_pubkey(),
+				Duration::from_secs(1_700_000_000),
+			)
+			.unwrap()
+			.build()
+			.unwrap()
+			.sign(recipient_sign)
+			.unwrap();
 
-		unsigned
-			.sign(|proof: &UnsignedPayerProof| {
-				Ok(secp_ctx.sign_schnorr_no_aux_rand(proof.as_ref().as_digest(), &payer_keys))
-			})
+		let paid_invoice =
+			PaidBolt12Invoice::new(Bolt12InvoiceType::Bolt12Invoice(invoice), preimage, None);
+		paid_invoice
+			.prove_payer()
+			.unwrap()
+			.include_offer_description()
+			.include_offer_issuer()
+			.include_invoice_amount()
+			.include_invoice_created_at()
+			.build()
+			.unwrap()
+			.sign(|proof: &UnsignedPayerProof| payer_sign(proof))
 			.unwrap()
 	}