+ #[test]
+ fn builds_offer_with_metadata_derived() {
+ let desc = "foo".to_string();
+ let node_id = recipient_pubkey();
+ let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
+ let entropy = FixedEntropy {};
+ let secp_ctx = Secp256k1::new();
+
+ let offer = OfferBuilder
+ ::deriving_signing_pubkey(desc, node_id, &expanded_key, &entropy, &secp_ctx)
+ .amount_msats(1000)
+ .build().unwrap();
+ assert_eq!(offer.signing_pubkey(), node_id);
+
+ let invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
+ .build().unwrap()
+ .sign(payer_sign).unwrap();
+ assert!(invoice_request.verify(&expanded_key, &secp_ctx).is_ok());
+
+ // Fails verification with altered offer field
+ let mut tlv_stream = offer.as_tlv_stream();
+ tlv_stream.amount = Some(100);
+
+ let mut encoded_offer = Vec::new();
+ tlv_stream.write(&mut encoded_offer).unwrap();
+
+ let invoice_request = Offer::try_from(encoded_offer).unwrap()
+ .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
+ .build().unwrap()
+ .sign(payer_sign).unwrap();
+ assert!(invoice_request.verify(&expanded_key, &secp_ctx).is_err());
+
+ // Fails verification with altered metadata
+ let mut tlv_stream = offer.as_tlv_stream();
+ let metadata = tlv_stream.metadata.unwrap().iter().copied().rev().collect();
+ tlv_stream.metadata = Some(&metadata);
+
+ let mut encoded_offer = Vec::new();
+ tlv_stream.write(&mut encoded_offer).unwrap();
+
+ let invoice_request = Offer::try_from(encoded_offer).unwrap()
+ .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
+ .build().unwrap()
+ .sign(payer_sign).unwrap();
+ assert!(invoice_request.verify(&expanded_key, &secp_ctx).is_err());
+ }
+
+ #[test]
+ fn builds_offer_with_derived_signing_pubkey() {
+ let desc = "foo".to_string();
+ let node_id = recipient_pubkey();
+ let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
+ let entropy = FixedEntropy {};
+ let secp_ctx = Secp256k1::new();
+
+ let blinded_path = BlindedPath {
+ introduction_node_id: pubkey(40),
+ blinding_point: pubkey(41),
+ blinded_hops: vec![
+ BlindedHop { blinded_node_id: pubkey(42), encrypted_payload: vec![0; 43] },
+ BlindedHop { blinded_node_id: node_id, encrypted_payload: vec![0; 44] },
+ ],
+ };
+
+ let offer = OfferBuilder
+ ::deriving_signing_pubkey(desc, node_id, &expanded_key, &entropy, &secp_ctx)
+ .amount_msats(1000)
+ .path(blinded_path)
+ .build().unwrap();
+ assert_ne!(offer.signing_pubkey(), node_id);
+
+ let invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
+ .build().unwrap()
+ .sign(payer_sign).unwrap();
+ assert!(invoice_request.verify(&expanded_key, &secp_ctx).is_ok());
+
+ // Fails verification with altered offer field
+ let mut tlv_stream = offer.as_tlv_stream();
+ tlv_stream.amount = Some(100);
+
+ let mut encoded_offer = Vec::new();
+ tlv_stream.write(&mut encoded_offer).unwrap();
+
+ let invoice_request = Offer::try_from(encoded_offer).unwrap()
+ .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
+ .build().unwrap()
+ .sign(payer_sign).unwrap();
+ assert!(invoice_request.verify(&expanded_key, &secp_ctx).is_err());
+
+ // Fails verification with altered signing pubkey
+ let mut tlv_stream = offer.as_tlv_stream();
+ let signing_pubkey = pubkey(1);
+ tlv_stream.node_id = Some(&signing_pubkey);
+
+ let mut encoded_offer = Vec::new();
+ tlv_stream.write(&mut encoded_offer).unwrap();
+
+ let invoice_request = Offer::try_from(encoded_offer).unwrap()
+ .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
+ .build().unwrap()
+ .sign(payer_sign).unwrap();
+ assert!(invoice_request.verify(&expanded_key, &secp_ctx).is_err());
+ }
+