Add c_bindings version of OfferBuilder
[rust-lightning] / lightning / src / offers / invoice.rs
1 // This file is Copyright its original authors, visible in version control
2 // history.
3 //
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
8 // licenses.
9
10 //! Data structures and encoding for `invoice` messages.
11 //!
12 //! A [`Bolt12Invoice`] can be built from a parsed [`InvoiceRequest`] for the "offer to be paid"
13 //! flow or from a [`Refund`] as an "offer for money" flow. The expected recipient of the payment
14 //! then sends the invoice to the intended payer, who will then pay it.
15 //!
16 //! The payment recipient must include a [`PaymentHash`], so as to reveal the preimage upon payment
17 //! receipt, and one or more [`BlindedPath`]s for the payer to use when sending the payment.
18 //!
19 //! ```
20 //! extern crate bitcoin;
21 //! extern crate lightning;
22 //!
23 //! use bitcoin::hashes::Hash;
24 //! use bitcoin::secp256k1::{KeyPair, PublicKey, Secp256k1, SecretKey};
25 //! use core::convert::{Infallible, TryFrom};
26 //! use lightning::offers::invoice_request::InvoiceRequest;
27 //! use lightning::offers::refund::Refund;
28 //! use lightning::util::ser::Writeable;
29 //!
30 //! # use lightning::ln::PaymentHash;
31 //! # use lightning::offers::invoice::BlindedPayInfo;
32 //! # use lightning::blinded_path::BlindedPath;
33 //! #
34 //! # fn create_payment_paths() -> Vec<(BlindedPayInfo, BlindedPath)> { unimplemented!() }
35 //! # fn create_payment_hash() -> PaymentHash { unimplemented!() }
36 //! #
37 //! # fn parse_invoice_request(bytes: Vec<u8>) -> Result<(), lightning::offers::parse::Bolt12ParseError> {
38 //! let payment_paths = create_payment_paths();
39 //! let payment_hash = create_payment_hash();
40 //! let secp_ctx = Secp256k1::new();
41 //! let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32])?);
42 //! let pubkey = PublicKey::from(keys);
43 //! let wpubkey_hash = bitcoin::key::PublicKey::new(pubkey).wpubkey_hash().unwrap();
44 //! let mut buffer = Vec::new();
45 //!
46 //! // Invoice for the "offer to be paid" flow.
47 //! InvoiceRequest::try_from(bytes)?
48 #![cfg_attr(feature = "std", doc = "
49     .respond_with(payment_paths, payment_hash)?
50 ")]
51 #![cfg_attr(not(feature = "std"), doc = "
52     .respond_with_no_std(payment_paths, payment_hash, core::time::Duration::from_secs(0))?
53 ")]
54 //!     .relative_expiry(3600)
55 //!     .allow_mpp()
56 //!     .fallback_v0_p2wpkh(&wpubkey_hash)
57 //!     .build()?
58 //!     .sign::<_, Infallible>(
59 //!         |message| Ok(secp_ctx.sign_schnorr_no_aux_rand(message.as_ref().as_digest(), &keys))
60 //!     )
61 //!     .expect("failed verifying signature")
62 //!     .write(&mut buffer)
63 //!     .unwrap();
64 //! # Ok(())
65 //! # }
66 //!
67 //! # fn parse_refund(bytes: Vec<u8>) -> Result<(), lightning::offers::parse::Bolt12ParseError> {
68 //! # let payment_paths = create_payment_paths();
69 //! # let payment_hash = create_payment_hash();
70 //! # let secp_ctx = Secp256k1::new();
71 //! # let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32])?);
72 //! # let pubkey = PublicKey::from(keys);
73 //! # let wpubkey_hash = bitcoin::key::PublicKey::new(pubkey).wpubkey_hash().unwrap();
74 //! # let mut buffer = Vec::new();
75 //!
76 //! // Invoice for the "offer for money" flow.
77 //! "lnr1qcp4256ypq"
78 //!     .parse::<Refund>()?
79 #![cfg_attr(feature = "std", doc = "
80     .respond_with(payment_paths, payment_hash, pubkey)?
81 ")]
82 #![cfg_attr(not(feature = "std"), doc = "
83     .respond_with_no_std(payment_paths, payment_hash, pubkey, core::time::Duration::from_secs(0))?
84 ")]
85 //!     .relative_expiry(3600)
86 //!     .allow_mpp()
87 //!     .fallback_v0_p2wpkh(&wpubkey_hash)
88 //!     .build()?
89 //!     .sign::<_, Infallible>(
90 //!         |message| Ok(secp_ctx.sign_schnorr_no_aux_rand(message.as_ref().as_digest(), &keys))
91 //!     )
92 //!     .expect("failed verifying signature")
93 //!     .write(&mut buffer)
94 //!     .unwrap();
95 //! # Ok(())
96 //! # }
97 //!
98 //! ```
99
100 use bitcoin::blockdata::constants::ChainHash;
101 use bitcoin::hash_types::{WPubkeyHash, WScriptHash};
102 use bitcoin::hashes::Hash;
103 use bitcoin::network::constants::Network;
104 use bitcoin::secp256k1::{KeyPair, PublicKey, Secp256k1, self};
105 use bitcoin::secp256k1::schnorr::Signature;
106 use bitcoin::address::{Address, Payload, WitnessProgram, WitnessVersion};
107 use bitcoin::key::TweakedPublicKey;
108 use core::convert::{AsRef, Infallible, TryFrom};
109 use core::time::Duration;
110 use crate::io;
111 use crate::blinded_path::BlindedPath;
112 use crate::ln::PaymentHash;
113 use crate::ln::channelmanager::PaymentId;
114 use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures, InvoiceRequestFeatures, OfferFeatures};
115 use crate::ln::inbound_payment::ExpandedKey;
116 use crate::ln::msgs::DecodeError;
117 use crate::offers::invoice_request::{INVOICE_REQUEST_PAYER_ID_TYPE, INVOICE_REQUEST_TYPES, IV_BYTES as INVOICE_REQUEST_IV_BYTES, InvoiceRequest, InvoiceRequestContents, InvoiceRequestTlvStream, InvoiceRequestTlvStreamRef};
118 use crate::offers::merkle::{SignError, SignatureTlvStream, SignatureTlvStreamRef, TaggedHash, TlvStream, WithoutSignatures, self};
119 use crate::offers::offer::{Amount, OFFER_TYPES, OfferTlvStream, OfferTlvStreamRef, Quantity};
120 use crate::offers::parse::{Bolt12ParseError, Bolt12SemanticError, ParsedMessage};
121 use crate::offers::payer::{PAYER_METADATA_TYPE, PayerTlvStream, PayerTlvStreamRef};
122 use crate::offers::refund::{IV_BYTES as REFUND_IV_BYTES, Refund, RefundContents};
123 use crate::offers::signer;
124 use crate::util::ser::{HighZeroBytesDroppedBigSize, Iterable, SeekReadable, WithoutLength, Writeable, Writer};
125 use crate::util::string::PrintableString;
126
127 use crate::prelude::*;
128
129 #[cfg(feature = "std")]
130 use std::time::SystemTime;
131
132 pub(crate) const DEFAULT_RELATIVE_EXPIRY: Duration = Duration::from_secs(7200);
133
134 /// Tag for the hash function used when signing a [`Bolt12Invoice`]'s merkle root.
135 pub const SIGNATURE_TAG: &'static str = concat!("lightning", "invoice", "signature");
136
137 /// Builds a [`Bolt12Invoice`] from either:
138 /// - an [`InvoiceRequest`] for the "offer to be paid" flow or
139 /// - a [`Refund`] for the "offer for money" flow.
140 ///
141 /// See [module-level documentation] for usage.
142 ///
143 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
144 ///
145 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
146 /// [`Refund`]: crate::offers::refund::Refund
147 /// [module-level documentation]: self
148 pub struct InvoiceBuilder<'a, S: SigningPubkeyStrategy> {
149         invreq_bytes: &'a Vec<u8>,
150         invoice: InvoiceContents,
151         signing_pubkey_strategy: S,
152 }
153
154 /// Indicates how [`Bolt12Invoice::signing_pubkey`] was set.
155 ///
156 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
157 pub trait SigningPubkeyStrategy {}
158
159 /// [`Bolt12Invoice::signing_pubkey`] was explicitly set.
160 ///
161 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
162 pub struct ExplicitSigningPubkey {}
163
164 /// [`Bolt12Invoice::signing_pubkey`] was derived.
165 ///
166 /// This is not exported to bindings users as builder patterns don't map outside of move semantics.
167 pub struct DerivedSigningPubkey(KeyPair);
168
169 impl SigningPubkeyStrategy for ExplicitSigningPubkey {}
170 impl SigningPubkeyStrategy for DerivedSigningPubkey {}
171
172 impl<'a> InvoiceBuilder<'a, ExplicitSigningPubkey> {
173         pub(super) fn for_offer(
174                 invoice_request: &'a InvoiceRequest, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>,
175                 created_at: Duration, payment_hash: PaymentHash
176         ) -> Result<Self, Bolt12SemanticError> {
177                 let amount_msats = Self::amount_msats(invoice_request)?;
178                 let signing_pubkey = invoice_request.contents.inner.offer.signing_pubkey();
179                 let contents = InvoiceContents::ForOffer {
180                         invoice_request: invoice_request.contents.clone(),
181                         fields: Self::fields(
182                                 payment_paths, created_at, payment_hash, amount_msats, signing_pubkey
183                         ),
184                 };
185
186                 Self::new(&invoice_request.bytes, contents, ExplicitSigningPubkey {})
187         }
188
189         pub(super) fn for_refund(
190                 refund: &'a Refund, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, created_at: Duration,
191                 payment_hash: PaymentHash, signing_pubkey: PublicKey
192         ) -> Result<Self, Bolt12SemanticError> {
193                 let amount_msats = refund.amount_msats();
194                 let contents = InvoiceContents::ForRefund {
195                         refund: refund.contents.clone(),
196                         fields: Self::fields(
197                                 payment_paths, created_at, payment_hash, amount_msats, signing_pubkey
198                         ),
199                 };
200
201                 Self::new(&refund.bytes, contents, ExplicitSigningPubkey {})
202         }
203 }
204
205 impl<'a> InvoiceBuilder<'a, DerivedSigningPubkey> {
206         pub(super) fn for_offer_using_keys(
207                 invoice_request: &'a InvoiceRequest, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>,
208                 created_at: Duration, payment_hash: PaymentHash, keys: KeyPair
209         ) -> Result<Self, Bolt12SemanticError> {
210                 let amount_msats = Self::amount_msats(invoice_request)?;
211                 let signing_pubkey = invoice_request.contents.inner.offer.signing_pubkey();
212                 let contents = InvoiceContents::ForOffer {
213                         invoice_request: invoice_request.contents.clone(),
214                         fields: Self::fields(
215                                 payment_paths, created_at, payment_hash, amount_msats, signing_pubkey
216                         ),
217                 };
218
219                 Self::new(&invoice_request.bytes, contents, DerivedSigningPubkey(keys))
220         }
221
222         pub(super) fn for_refund_using_keys(
223                 refund: &'a Refund, payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, created_at: Duration,
224                 payment_hash: PaymentHash, keys: KeyPair,
225         ) -> Result<Self, Bolt12SemanticError> {
226                 let amount_msats = refund.amount_msats();
227                 let signing_pubkey = keys.public_key();
228                 let contents = InvoiceContents::ForRefund {
229                         refund: refund.contents.clone(),
230                         fields: Self::fields(
231                                 payment_paths, created_at, payment_hash, amount_msats, signing_pubkey
232                         ),
233                 };
234
235                 Self::new(&refund.bytes, contents, DerivedSigningPubkey(keys))
236         }
237 }
238
239 impl<'a, S: SigningPubkeyStrategy> InvoiceBuilder<'a, S> {
240         pub(crate) fn amount_msats(
241                 invoice_request: &InvoiceRequest
242         ) -> Result<u64, Bolt12SemanticError> {
243                 match invoice_request.amount_msats() {
244                         Some(amount_msats) => Ok(amount_msats),
245                         None => match invoice_request.contents.inner.offer.amount() {
246                                 Some(Amount::Bitcoin { amount_msats }) => {
247                                         amount_msats.checked_mul(invoice_request.quantity().unwrap_or(1))
248                                                 .ok_or(Bolt12SemanticError::InvalidAmount)
249                                 },
250                                 Some(Amount::Currency { .. }) => Err(Bolt12SemanticError::UnsupportedCurrency),
251                                 None => Err(Bolt12SemanticError::MissingAmount),
252                         },
253                 }
254         }
255
256         fn fields(
257                 payment_paths: Vec<(BlindedPayInfo, BlindedPath)>, created_at: Duration,
258                 payment_hash: PaymentHash, amount_msats: u64, signing_pubkey: PublicKey
259         ) -> InvoiceFields {
260                 InvoiceFields {
261                         payment_paths, created_at, relative_expiry: None, payment_hash, amount_msats,
262                         fallbacks: None, features: Bolt12InvoiceFeatures::empty(), signing_pubkey,
263                 }
264         }
265
266         fn new(
267                 invreq_bytes: &'a Vec<u8>, contents: InvoiceContents, signing_pubkey_strategy: S
268         ) -> Result<Self, Bolt12SemanticError> {
269                 if contents.fields().payment_paths.is_empty() {
270                         return Err(Bolt12SemanticError::MissingPaths);
271                 }
272
273                 Ok(Self { invreq_bytes, invoice: contents, signing_pubkey_strategy })
274         }
275
276         /// Sets the [`Bolt12Invoice::relative_expiry`] as seconds since [`Bolt12Invoice::created_at`].
277         /// Any expiry that has already passed is valid and can be checked for using
278         /// [`Bolt12Invoice::is_expired`].
279         ///
280         /// Successive calls to this method will override the previous setting.
281         pub fn relative_expiry(mut self, relative_expiry_secs: u32) -> Self {
282                 let relative_expiry = Duration::from_secs(relative_expiry_secs as u64);
283                 self.invoice.fields_mut().relative_expiry = Some(relative_expiry);
284                 self
285         }
286
287         /// Adds a P2WSH address to [`Bolt12Invoice::fallbacks`].
288         ///
289         /// Successive calls to this method will add another address. Caller is responsible for not
290         /// adding duplicate addresses and only calling if capable of receiving to P2WSH addresses.
291         pub fn fallback_v0_p2wsh(mut self, script_hash: &WScriptHash) -> Self {
292                 let address = FallbackAddress {
293                         version: WitnessVersion::V0.to_num(),
294                         program: Vec::from(script_hash.to_byte_array()),
295                 };
296                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
297                 self
298         }
299
300         /// Adds a P2WPKH address to [`Bolt12Invoice::fallbacks`].
301         ///
302         /// Successive calls to this method will add another address. Caller is responsible for not
303         /// adding duplicate addresses and only calling if capable of receiving to P2WPKH addresses.
304         pub fn fallback_v0_p2wpkh(mut self, pubkey_hash: &WPubkeyHash) -> Self {
305                 let address = FallbackAddress {
306                         version: WitnessVersion::V0.to_num(),
307                         program: Vec::from(pubkey_hash.to_byte_array()),
308                 };
309                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
310                 self
311         }
312
313         /// Adds a P2TR address to [`Bolt12Invoice::fallbacks`].
314         ///
315         /// Successive calls to this method will add another address. Caller is responsible for not
316         /// adding duplicate addresses and only calling if capable of receiving to P2TR addresses.
317         pub fn fallback_v1_p2tr_tweaked(mut self, output_key: &TweakedPublicKey) -> Self {
318                 let address = FallbackAddress {
319                         version: WitnessVersion::V1.to_num(),
320                         program: Vec::from(&output_key.serialize()[..]),
321                 };
322                 self.invoice.fields_mut().fallbacks.get_or_insert_with(Vec::new).push(address);
323                 self
324         }
325
326         /// Sets [`Bolt12Invoice::invoice_features`] to indicate MPP may be used. Otherwise, MPP is
327         /// disallowed.
328         pub fn allow_mpp(mut self) -> Self {
329                 self.invoice.fields_mut().features.set_basic_mpp_optional();
330                 self
331         }
332 }
333
334 impl<'a> InvoiceBuilder<'a, ExplicitSigningPubkey> {
335         /// Builds an unsigned [`Bolt12Invoice`] after checking for valid semantics. It can be signed by
336         /// [`UnsignedBolt12Invoice::sign`].
337         pub fn build(self) -> Result<UnsignedBolt12Invoice, Bolt12SemanticError> {
338                 #[cfg(feature = "std")] {
339                         if self.invoice.is_offer_or_refund_expired() {
340                                 return Err(Bolt12SemanticError::AlreadyExpired);
341                         }
342                 }
343
344                 #[cfg(not(feature = "std"))] {
345                         if self.invoice.is_offer_or_refund_expired_no_std(self.invoice.created_at()) {
346                                 return Err(Bolt12SemanticError::AlreadyExpired);
347                         }
348                 }
349
350                 let InvoiceBuilder { invreq_bytes, invoice, .. } = self;
351                 Ok(UnsignedBolt12Invoice::new(invreq_bytes, invoice))
352         }
353 }
354
355 impl<'a> InvoiceBuilder<'a, DerivedSigningPubkey> {
356         /// Builds a signed [`Bolt12Invoice`] after checking for valid semantics.
357         pub fn build_and_sign<T: secp256k1::Signing>(
358                 self, secp_ctx: &Secp256k1<T>
359         ) -> Result<Bolt12Invoice, Bolt12SemanticError> {
360                 #[cfg(feature = "std")] {
361                         if self.invoice.is_offer_or_refund_expired() {
362                                 return Err(Bolt12SemanticError::AlreadyExpired);
363                         }
364                 }
365
366                 #[cfg(not(feature = "std"))] {
367                         if self.invoice.is_offer_or_refund_expired_no_std(self.invoice.created_at()) {
368                                 return Err(Bolt12SemanticError::AlreadyExpired);
369                         }
370                 }
371
372                 let InvoiceBuilder {
373                         invreq_bytes, invoice, signing_pubkey_strategy: DerivedSigningPubkey(keys)
374                 } = self;
375                 let unsigned_invoice = UnsignedBolt12Invoice::new(invreq_bytes, invoice);
376
377                 let invoice = unsigned_invoice
378                         .sign::<_, Infallible>(
379                                 |message| Ok(secp_ctx.sign_schnorr_no_aux_rand(message.as_ref().as_digest(), &keys))
380                         )
381                         .unwrap();
382                 Ok(invoice)
383         }
384 }
385
386 /// A semantically valid [`Bolt12Invoice`] that hasn't been signed.
387 ///
388 /// # Serialization
389 ///
390 /// This is serialized as a TLV stream, which includes TLV records from the originating message. As
391 /// such, it may include unknown, odd TLV records.
392 pub struct UnsignedBolt12Invoice {
393         bytes: Vec<u8>,
394         contents: InvoiceContents,
395         tagged_hash: TaggedHash,
396 }
397
398 impl UnsignedBolt12Invoice {
399         fn new(invreq_bytes: &[u8], contents: InvoiceContents) -> Self {
400                 // Use the invoice_request bytes instead of the invoice_request TLV stream as the latter may
401                 // have contained unknown TLV records, which are not stored in `InvoiceRequestContents` or
402                 // `RefundContents`.
403                 let (_, _, _, invoice_tlv_stream) = contents.as_tlv_stream();
404                 let invoice_request_bytes = WithoutSignatures(invreq_bytes);
405                 let unsigned_tlv_stream = (invoice_request_bytes, invoice_tlv_stream);
406
407                 let mut bytes = Vec::new();
408                 unsigned_tlv_stream.write(&mut bytes).unwrap();
409
410                 let tagged_hash = TaggedHash::new(SIGNATURE_TAG, &bytes);
411
412                 Self { bytes, contents, tagged_hash }
413         }
414
415         /// Returns the [`TaggedHash`] of the invoice to sign.
416         pub fn tagged_hash(&self) -> &TaggedHash {
417                 &self.tagged_hash
418         }
419
420         /// Signs the [`TaggedHash`] of the invoice using the given function.
421         ///
422         /// Note: The hash computation may have included unknown, odd TLV records.
423         ///
424         /// This is not exported to bindings users as functions aren't currently mapped.
425         pub fn sign<F, E>(mut self, sign: F) -> Result<Bolt12Invoice, SignError<E>>
426         where
427                 F: FnOnce(&Self) -> Result<Signature, E>
428         {
429                 let pubkey = self.contents.fields().signing_pubkey;
430                 let signature = merkle::sign_message(sign, &self, pubkey)?;
431
432                 // Append the signature TLV record to the bytes.
433                 let signature_tlv_stream = SignatureTlvStreamRef {
434                         signature: Some(&signature),
435                 };
436                 signature_tlv_stream.write(&mut self.bytes).unwrap();
437
438                 Ok(Bolt12Invoice {
439                         bytes: self.bytes,
440                         contents: self.contents,
441                         signature,
442                         tagged_hash: self.tagged_hash,
443                 })
444         }
445 }
446
447 impl AsRef<TaggedHash> for UnsignedBolt12Invoice {
448         fn as_ref(&self) -> &TaggedHash {
449                 &self.tagged_hash
450         }
451 }
452
453 /// A `Bolt12Invoice` is a payment request, typically corresponding to an [`Offer`] or a [`Refund`].
454 ///
455 /// An invoice may be sent in response to an [`InvoiceRequest`] in the case of an offer or sent
456 /// directly after scanning a refund. It includes all the information needed to pay a recipient.
457 ///
458 /// [`Offer`]: crate::offers::offer::Offer
459 /// [`Refund`]: crate::offers::refund::Refund
460 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
461 #[derive(Clone, Debug)]
462 #[cfg_attr(test, derive(PartialEq))]
463 pub struct Bolt12Invoice {
464         bytes: Vec<u8>,
465         contents: InvoiceContents,
466         signature: Signature,
467         tagged_hash: TaggedHash,
468 }
469
470 /// The contents of an [`Bolt12Invoice`] for responding to either an [`Offer`] or a [`Refund`].
471 ///
472 /// [`Offer`]: crate::offers::offer::Offer
473 /// [`Refund`]: crate::offers::refund::Refund
474 #[derive(Clone, Debug)]
475 #[cfg_attr(test, derive(PartialEq))]
476 enum InvoiceContents {
477         /// Contents for an [`Bolt12Invoice`] corresponding to an [`Offer`].
478         ///
479         /// [`Offer`]: crate::offers::offer::Offer
480         ForOffer {
481                 invoice_request: InvoiceRequestContents,
482                 fields: InvoiceFields,
483         },
484         /// Contents for an [`Bolt12Invoice`] corresponding to a [`Refund`].
485         ///
486         /// [`Refund`]: crate::offers::refund::Refund
487         ForRefund {
488                 refund: RefundContents,
489                 fields: InvoiceFields,
490         },
491 }
492
493 /// Invoice-specific fields for an `invoice` message.
494 #[derive(Clone, Debug, PartialEq)]
495 struct InvoiceFields {
496         payment_paths: Vec<(BlindedPayInfo, BlindedPath)>,
497         created_at: Duration,
498         relative_expiry: Option<Duration>,
499         payment_hash: PaymentHash,
500         amount_msats: u64,
501         fallbacks: Option<Vec<FallbackAddress>>,
502         features: Bolt12InvoiceFeatures,
503         signing_pubkey: PublicKey,
504 }
505
506 macro_rules! invoice_accessors { ($self: ident, $contents: expr) => {
507         /// The chains that may be used when paying a requested invoice.
508         ///
509         /// From [`Offer::chains`]; `None` if the invoice was created in response to a [`Refund`].
510         ///
511         /// [`Offer::chains`]: crate::offers::offer::Offer::chains
512         pub fn offer_chains(&$self) -> Option<Vec<ChainHash>> {
513                 $contents.offer_chains()
514         }
515
516         /// The chain that must be used when paying the invoice; selected from [`offer_chains`] if the
517         /// invoice originated from an offer.
518         ///
519         /// From [`InvoiceRequest::chain`] or [`Refund::chain`].
520         ///
521         /// [`offer_chains`]: Self::offer_chains
522         /// [`InvoiceRequest::chain`]: crate::offers::invoice_request::InvoiceRequest::chain
523         pub fn chain(&$self) -> ChainHash {
524                 $contents.chain()
525         }
526
527         /// Opaque bytes set by the originating [`Offer`].
528         ///
529         /// From [`Offer::metadata`]; `None` if the invoice was created in response to a [`Refund`] or
530         /// if the [`Offer`] did not set it.
531         ///
532         /// [`Offer`]: crate::offers::offer::Offer
533         /// [`Offer::metadata`]: crate::offers::offer::Offer::metadata
534         pub fn metadata(&$self) -> Option<&Vec<u8>> {
535                 $contents.metadata()
536         }
537
538         /// The minimum amount required for a successful payment of a single item.
539         ///
540         /// From [`Offer::amount`]; `None` if the invoice was created in response to a [`Refund`] or if
541         /// the [`Offer`] did not set it.
542         ///
543         /// [`Offer`]: crate::offers::offer::Offer
544         /// [`Offer::amount`]: crate::offers::offer::Offer::amount
545         pub fn amount(&$self) -> Option<&Amount> {
546                 $contents.amount()
547         }
548
549         /// Features pertaining to the originating [`Offer`].
550         ///
551         /// From [`Offer::offer_features`]; `None` if the invoice was created in response to a
552         /// [`Refund`].
553         ///
554         /// [`Offer`]: crate::offers::offer::Offer
555         /// [`Offer::offer_features`]: crate::offers::offer::Offer::offer_features
556         pub fn offer_features(&$self) -> Option<&OfferFeatures> {
557                 $contents.offer_features()
558         }
559
560         /// A complete description of the purpose of the originating offer or refund.
561         ///
562         /// From [`Offer::description`] or [`Refund::description`].
563         ///
564         /// [`Offer::description`]: crate::offers::offer::Offer::description
565         pub fn description(&$self) -> PrintableString {
566                 $contents.description()
567         }
568
569         /// Duration since the Unix epoch when an invoice should no longer be requested.
570         ///
571         /// From [`Offer::absolute_expiry`] or [`Refund::absolute_expiry`].
572         ///
573         /// [`Offer::absolute_expiry`]: crate::offers::offer::Offer::absolute_expiry
574         pub fn absolute_expiry(&$self) -> Option<Duration> {
575                 $contents.absolute_expiry()
576         }
577
578         /// The issuer of the offer or refund.
579         ///
580         /// From [`Offer::issuer`] or [`Refund::issuer`].
581         ///
582         /// [`Offer::issuer`]: crate::offers::offer::Offer::issuer
583         pub fn issuer(&$self) -> Option<PrintableString> {
584                 $contents.issuer()
585         }
586
587         /// Paths to the recipient originating from publicly reachable nodes.
588         ///
589         /// From [`Offer::paths`] or [`Refund::paths`].
590         ///
591         /// [`Offer::paths`]: crate::offers::offer::Offer::paths
592         pub fn message_paths(&$self) -> &[BlindedPath] {
593                 $contents.message_paths()
594         }
595
596         /// The quantity of items supported.
597         ///
598         /// From [`Offer::supported_quantity`]; `None` if the invoice was created in response to a
599         /// [`Refund`].
600         ///
601         /// [`Offer::supported_quantity`]: crate::offers::offer::Offer::supported_quantity
602         pub fn supported_quantity(&$self) -> Option<Quantity> {
603                 $contents.supported_quantity()
604         }
605
606         /// An unpredictable series of bytes from the payer.
607         ///
608         /// From [`InvoiceRequest::payer_metadata`] or [`Refund::payer_metadata`].
609         pub fn payer_metadata(&$self) -> &[u8] {
610                 $contents.payer_metadata()
611         }
612
613         /// Features pertaining to requesting an invoice.
614         ///
615         /// From [`InvoiceRequest::invoice_request_features`] or [`Refund::features`].
616         pub fn invoice_request_features(&$self) -> &InvoiceRequestFeatures {
617                 &$contents.invoice_request_features()
618         }
619
620         /// The quantity of items requested or refunded for.
621         ///
622         /// From [`InvoiceRequest::quantity`] or [`Refund::quantity`].
623         pub fn quantity(&$self) -> Option<u64> {
624                 $contents.quantity()
625         }
626
627         /// A possibly transient pubkey used to sign the invoice request or to send an invoice for a
628         /// refund in case there are no [`message_paths`].
629         ///
630         /// [`message_paths`]: Self::message_paths
631         pub fn payer_id(&$self) -> PublicKey {
632                 $contents.payer_id()
633         }
634
635         /// A payer-provided note reflected back in the invoice.
636         ///
637         /// From [`InvoiceRequest::payer_note`] or [`Refund::payer_note`].
638         pub fn payer_note(&$self) -> Option<PrintableString> {
639                 $contents.payer_note()
640         }
641
642         /// Paths to the recipient originating from publicly reachable nodes, including information
643         /// needed for routing payments across them.
644         ///
645         /// Blinded paths provide recipient privacy by obfuscating its node id. Note, however, that this
646         /// privacy is lost if a public node id is used for [`Bolt12Invoice::signing_pubkey`].
647         ///
648         /// This is not exported to bindings users as slices with non-reference types cannot be ABI
649         /// matched in another language.
650         pub fn payment_paths(&$self) -> &[(BlindedPayInfo, BlindedPath)] {
651                 $contents.payment_paths()
652         }
653
654         /// Duration since the Unix epoch when the invoice was created.
655         pub fn created_at(&$self) -> Duration {
656                 $contents.created_at()
657         }
658
659         /// Duration since [`Bolt12Invoice::created_at`] when the invoice has expired and therefore
660         /// should no longer be paid.
661         pub fn relative_expiry(&$self) -> Duration {
662                 $contents.relative_expiry()
663         }
664
665         /// Whether the invoice has expired.
666         #[cfg(feature = "std")]
667         pub fn is_expired(&$self) -> bool {
668                 $contents.is_expired()
669         }
670
671         /// SHA256 hash of the payment preimage that will be given in return for paying the invoice.
672         pub fn payment_hash(&$self) -> PaymentHash {
673                 $contents.payment_hash()
674         }
675
676         /// The minimum amount required for a successful payment of the invoice.
677         pub fn amount_msats(&$self) -> u64 {
678                 $contents.amount_msats()
679         }
680
681         /// Fallback addresses for paying the invoice on-chain, in order of most-preferred to
682         /// least-preferred.
683         pub fn fallbacks(&$self) -> Vec<Address> {
684                 $contents.fallbacks()
685         }
686
687         /// Features pertaining to paying an invoice.
688         pub fn invoice_features(&$self) -> &Bolt12InvoiceFeatures {
689                 $contents.features()
690         }
691
692         /// The public key corresponding to the key used to sign the invoice.
693         pub fn signing_pubkey(&$self) -> PublicKey {
694                 $contents.signing_pubkey()
695         }
696 } }
697
698 impl UnsignedBolt12Invoice {
699         invoice_accessors!(self, self.contents);
700 }
701
702 impl Bolt12Invoice {
703         invoice_accessors!(self, self.contents);
704
705         /// Signature of the invoice verified using [`Bolt12Invoice::signing_pubkey`].
706         pub fn signature(&self) -> Signature {
707                 self.signature
708         }
709
710         /// Hash that was used for signing the invoice.
711         pub fn signable_hash(&self) -> [u8; 32] {
712                 self.tagged_hash.as_digest().as_ref().clone()
713         }
714
715         /// Verifies that the invoice was for a request or refund created using the given key. Returns
716         /// the associated [`PaymentId`] to use when sending the payment.
717         pub fn verify<T: secp256k1::Signing>(
718                 &self, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
719         ) -> Result<PaymentId, ()> {
720                 self.contents.verify(TlvStream::new(&self.bytes), key, secp_ctx)
721         }
722
723         pub(crate) fn as_tlv_stream(&self) -> FullInvoiceTlvStreamRef {
724                 let (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream) =
725                         self.contents.as_tlv_stream();
726                 let signature_tlv_stream = SignatureTlvStreamRef {
727                         signature: Some(&self.signature),
728                 };
729                 (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
730                  signature_tlv_stream)
731         }
732 }
733
734 impl InvoiceContents {
735         /// Whether the original offer or refund has expired.
736         #[cfg(feature = "std")]
737         fn is_offer_or_refund_expired(&self) -> bool {
738                 match self {
739                         InvoiceContents::ForOffer { invoice_request, .. } =>
740                                 invoice_request.inner.offer.is_expired(),
741                         InvoiceContents::ForRefund { refund, .. } => refund.is_expired(),
742                 }
743         }
744
745         #[cfg(not(feature = "std"))]
746         fn is_offer_or_refund_expired_no_std(&self, duration_since_epoch: Duration) -> bool {
747                 match self {
748                         InvoiceContents::ForOffer { invoice_request, .. } =>
749                                 invoice_request.inner.offer.is_expired_no_std(duration_since_epoch),
750                         InvoiceContents::ForRefund { refund, .. } =>
751                                 refund.is_expired_no_std(duration_since_epoch),
752                 }
753         }
754
755         fn offer_chains(&self) -> Option<Vec<ChainHash>> {
756                 match self {
757                         InvoiceContents::ForOffer { invoice_request, .. } =>
758                                 Some(invoice_request.inner.offer.chains()),
759                         InvoiceContents::ForRefund { .. } => None,
760                 }
761         }
762
763         fn chain(&self) -> ChainHash {
764                 match self {
765                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.chain(),
766                         InvoiceContents::ForRefund { refund, .. } => refund.chain(),
767                 }
768         }
769
770         fn metadata(&self) -> Option<&Vec<u8>> {
771                 match self {
772                         InvoiceContents::ForOffer { invoice_request, .. } =>
773                                 invoice_request.inner.offer.metadata(),
774                         InvoiceContents::ForRefund { .. } => None,
775                 }
776         }
777
778         fn amount(&self) -> Option<&Amount> {
779                 match self {
780                         InvoiceContents::ForOffer { invoice_request, .. } =>
781                                 invoice_request.inner.offer.amount(),
782                         InvoiceContents::ForRefund { .. } => None,
783                 }
784         }
785
786         fn description(&self) -> PrintableString {
787                 match self {
788                         InvoiceContents::ForOffer { invoice_request, .. } => {
789                                 invoice_request.inner.offer.description()
790                         },
791                         InvoiceContents::ForRefund { refund, .. } => refund.description(),
792                 }
793         }
794
795         fn offer_features(&self) -> Option<&OfferFeatures> {
796                 match self {
797                         InvoiceContents::ForOffer { invoice_request, .. } => {
798                                 Some(invoice_request.inner.offer.features())
799                         },
800                         InvoiceContents::ForRefund { .. } => None,
801                 }
802         }
803
804         fn absolute_expiry(&self) -> Option<Duration> {
805                 match self {
806                         InvoiceContents::ForOffer { invoice_request, .. } => {
807                                 invoice_request.inner.offer.absolute_expiry()
808                         },
809                         InvoiceContents::ForRefund { refund, .. } => refund.absolute_expiry(),
810                 }
811         }
812
813         fn issuer(&self) -> Option<PrintableString> {
814                 match self {
815                         InvoiceContents::ForOffer { invoice_request, .. } => {
816                                 invoice_request.inner.offer.issuer()
817                         },
818                         InvoiceContents::ForRefund { refund, .. } => refund.issuer(),
819                 }
820         }
821
822         fn message_paths(&self) -> &[BlindedPath] {
823                 match self {
824                         InvoiceContents::ForOffer { invoice_request, .. } => {
825                                 invoice_request.inner.offer.paths()
826                         },
827                         InvoiceContents::ForRefund { refund, .. } => refund.paths(),
828                 }
829         }
830
831         fn supported_quantity(&self) -> Option<Quantity> {
832                 match self {
833                         InvoiceContents::ForOffer { invoice_request, .. } => {
834                                 Some(invoice_request.inner.offer.supported_quantity())
835                         },
836                         InvoiceContents::ForRefund { .. } => None,
837                 }
838         }
839
840         fn payer_metadata(&self) -> &[u8] {
841                 match self {
842                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.metadata(),
843                         InvoiceContents::ForRefund { refund, .. } => refund.metadata(),
844                 }
845         }
846
847         fn invoice_request_features(&self) -> &InvoiceRequestFeatures {
848                 match self {
849                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.features(),
850                         InvoiceContents::ForRefund { refund, .. } => refund.features(),
851                 }
852         }
853
854         fn quantity(&self) -> Option<u64> {
855                 match self {
856                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.quantity(),
857                         InvoiceContents::ForRefund { refund, .. } => refund.quantity(),
858                 }
859         }
860
861         fn payer_id(&self) -> PublicKey {
862                 match self {
863                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.payer_id(),
864                         InvoiceContents::ForRefund { refund, .. } => refund.payer_id(),
865                 }
866         }
867
868         fn payer_note(&self) -> Option<PrintableString> {
869                 match self {
870                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.payer_note(),
871                         InvoiceContents::ForRefund { refund, .. } => refund.payer_note(),
872                 }
873         }
874
875         fn payment_paths(&self) -> &[(BlindedPayInfo, BlindedPath)] {
876                 &self.fields().payment_paths[..]
877         }
878
879         fn created_at(&self) -> Duration {
880                 self.fields().created_at
881         }
882
883         fn relative_expiry(&self) -> Duration {
884                 self.fields().relative_expiry.unwrap_or(DEFAULT_RELATIVE_EXPIRY)
885         }
886
887         #[cfg(feature = "std")]
888         fn is_expired(&self) -> bool {
889                 let absolute_expiry = self.created_at().checked_add(self.relative_expiry());
890                 match absolute_expiry {
891                         Some(seconds_from_epoch) => match SystemTime::UNIX_EPOCH.elapsed() {
892                                 Ok(elapsed) => elapsed > seconds_from_epoch,
893                                 Err(_) => false,
894                         },
895                         None => false,
896                 }
897         }
898
899         fn payment_hash(&self) -> PaymentHash {
900                 self.fields().payment_hash
901         }
902
903         fn amount_msats(&self) -> u64 {
904                 self.fields().amount_msats
905         }
906
907         fn fallbacks(&self) -> Vec<Address> {
908                 let chain = self.chain();
909                 let network = if chain == ChainHash::using_genesis_block(Network::Bitcoin) {
910                         Network::Bitcoin
911                 } else if chain == ChainHash::using_genesis_block(Network::Testnet) {
912                         Network::Testnet
913                 } else if chain == ChainHash::using_genesis_block(Network::Signet) {
914                         Network::Signet
915                 } else if chain == ChainHash::using_genesis_block(Network::Regtest) {
916                         Network::Regtest
917                 } else {
918                         return Vec::new()
919                 };
920
921                 let to_valid_address = |address: &FallbackAddress| {
922                         let version = match WitnessVersion::try_from(address.version) {
923                                 Ok(version) => version,
924                                 Err(_) => return None,
925                         };
926
927                         let program = &address.program;
928                         let witness_program = match WitnessProgram::new(version, program.clone()) {
929                                 Ok(witness_program) => witness_program,
930                                 Err(_) => return None,
931                         };
932                         Some(Address::new(network, Payload::WitnessProgram(witness_program)))
933                 };
934
935                 self.fields().fallbacks
936                         .as_ref()
937                         .map(|fallbacks| fallbacks.iter().filter_map(to_valid_address).collect())
938                         .unwrap_or_else(Vec::new)
939         }
940
941         fn features(&self) -> &Bolt12InvoiceFeatures {
942                 &self.fields().features
943         }
944
945         fn signing_pubkey(&self) -> PublicKey {
946                 self.fields().signing_pubkey
947         }
948
949         fn fields(&self) -> &InvoiceFields {
950                 match self {
951                         InvoiceContents::ForOffer { fields, .. } => fields,
952                         InvoiceContents::ForRefund { fields, .. } => fields,
953                 }
954         }
955
956         fn fields_mut(&mut self) -> &mut InvoiceFields {
957                 match self {
958                         InvoiceContents::ForOffer { fields, .. } => fields,
959                         InvoiceContents::ForRefund { fields, .. } => fields,
960                 }
961         }
962
963         fn verify<T: secp256k1::Signing>(
964                 &self, tlv_stream: TlvStream<'_>, key: &ExpandedKey, secp_ctx: &Secp256k1<T>
965         ) -> Result<PaymentId, ()> {
966                 let offer_records = tlv_stream.clone().range(OFFER_TYPES);
967                 let invreq_records = tlv_stream.range(INVOICE_REQUEST_TYPES).filter(|record| {
968                         match record.r#type {
969                                 PAYER_METADATA_TYPE => false, // Should be outside range
970                                 INVOICE_REQUEST_PAYER_ID_TYPE => !self.derives_keys(),
971                                 _ => true,
972                         }
973                 });
974                 let tlv_stream = offer_records.chain(invreq_records);
975
976                 let (metadata, payer_id, iv_bytes) = match self {
977                         InvoiceContents::ForOffer { invoice_request, .. } => {
978                                 (invoice_request.metadata(), invoice_request.payer_id(), INVOICE_REQUEST_IV_BYTES)
979                         },
980                         InvoiceContents::ForRefund { refund, .. } => {
981                                 (refund.metadata(), refund.payer_id(), REFUND_IV_BYTES)
982                         },
983                 };
984
985                 signer::verify_payer_metadata(metadata, key, iv_bytes, payer_id, tlv_stream, secp_ctx)
986         }
987
988         fn derives_keys(&self) -> bool {
989                 match self {
990                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.derives_keys(),
991                         InvoiceContents::ForRefund { refund, .. } => refund.derives_keys(),
992                 }
993         }
994
995         fn as_tlv_stream(&self) -> PartialInvoiceTlvStreamRef {
996                 let (payer, offer, invoice_request) = match self {
997                         InvoiceContents::ForOffer { invoice_request, .. } => invoice_request.as_tlv_stream(),
998                         InvoiceContents::ForRefund { refund, .. } => refund.as_tlv_stream(),
999                 };
1000                 let invoice = self.fields().as_tlv_stream();
1001
1002                 (payer, offer, invoice_request, invoice)
1003         }
1004 }
1005
1006 impl InvoiceFields {
1007         fn as_tlv_stream(&self) -> InvoiceTlvStreamRef {
1008                 let features = {
1009                         if self.features == Bolt12InvoiceFeatures::empty() { None }
1010                         else { Some(&self.features) }
1011                 };
1012
1013                 InvoiceTlvStreamRef {
1014                         paths: Some(Iterable(self.payment_paths.iter().map(|(_, path)| path))),
1015                         blindedpay: Some(Iterable(self.payment_paths.iter().map(|(payinfo, _)| payinfo))),
1016                         created_at: Some(self.created_at.as_secs()),
1017                         relative_expiry: self.relative_expiry.map(|duration| duration.as_secs() as u32),
1018                         payment_hash: Some(&self.payment_hash),
1019                         amount: Some(self.amount_msats),
1020                         fallbacks: self.fallbacks.as_ref(),
1021                         features,
1022                         node_id: Some(&self.signing_pubkey),
1023                 }
1024         }
1025 }
1026
1027 impl Writeable for UnsignedBolt12Invoice {
1028         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1029                 WithoutLength(&self.bytes).write(writer)
1030         }
1031 }
1032
1033 impl Writeable for Bolt12Invoice {
1034         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1035                 WithoutLength(&self.bytes).write(writer)
1036         }
1037 }
1038
1039 impl Writeable for InvoiceContents {
1040         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1041                 self.as_tlv_stream().write(writer)
1042         }
1043 }
1044
1045 impl TryFrom<Vec<u8>> for UnsignedBolt12Invoice {
1046         type Error = Bolt12ParseError;
1047
1048         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1049                 let invoice = ParsedMessage::<PartialInvoiceTlvStream>::try_from(bytes)?;
1050                 let ParsedMessage { bytes, tlv_stream } = invoice;
1051                 let (
1052                         payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
1053                 ) = tlv_stream;
1054                 let contents = InvoiceContents::try_from(
1055                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream)
1056                 )?;
1057
1058                 let tagged_hash = TaggedHash::new(SIGNATURE_TAG, &bytes);
1059
1060                 Ok(UnsignedBolt12Invoice { bytes, contents, tagged_hash })
1061         }
1062 }
1063
1064 impl TryFrom<Vec<u8>> for Bolt12Invoice {
1065         type Error = Bolt12ParseError;
1066
1067         fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
1068                 let parsed_invoice = ParsedMessage::<FullInvoiceTlvStream>::try_from(bytes)?;
1069                 Bolt12Invoice::try_from(parsed_invoice)
1070         }
1071 }
1072
1073 tlv_stream!(InvoiceTlvStream, InvoiceTlvStreamRef, 160..240, {
1074         (160, paths: (Vec<BlindedPath>, WithoutLength, Iterable<'a, BlindedPathIter<'a>, BlindedPath>)),
1075         (162, blindedpay: (Vec<BlindedPayInfo>, WithoutLength, Iterable<'a, BlindedPayInfoIter<'a>, BlindedPayInfo>)),
1076         (164, created_at: (u64, HighZeroBytesDroppedBigSize)),
1077         (166, relative_expiry: (u32, HighZeroBytesDroppedBigSize)),
1078         (168, payment_hash: PaymentHash),
1079         (170, amount: (u64, HighZeroBytesDroppedBigSize)),
1080         (172, fallbacks: (Vec<FallbackAddress>, WithoutLength)),
1081         (174, features: (Bolt12InvoiceFeatures, WithoutLength)),
1082         (176, node_id: PublicKey),
1083 });
1084
1085 type BlindedPathIter<'a> = core::iter::Map<
1086         core::slice::Iter<'a, (BlindedPayInfo, BlindedPath)>,
1087         for<'r> fn(&'r (BlindedPayInfo, BlindedPath)) -> &'r BlindedPath,
1088 >;
1089
1090 type BlindedPayInfoIter<'a> = core::iter::Map<
1091         core::slice::Iter<'a, (BlindedPayInfo, BlindedPath)>,
1092         for<'r> fn(&'r (BlindedPayInfo, BlindedPath)) -> &'r BlindedPayInfo,
1093 >;
1094
1095 /// Information needed to route a payment across a [`BlindedPath`].
1096 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
1097 pub struct BlindedPayInfo {
1098         /// Base fee charged (in millisatoshi) for the entire blinded path.
1099         pub fee_base_msat: u32,
1100
1101         /// Liquidity fee charged (in millionths of the amount transferred) for the entire blinded path
1102         /// (i.e., 10,000 is 1%).
1103         pub fee_proportional_millionths: u32,
1104
1105         /// Number of blocks subtracted from an incoming HTLC's `cltv_expiry` for the entire blinded
1106         /// path.
1107         pub cltv_expiry_delta: u16,
1108
1109         /// The minimum HTLC value (in millisatoshi) that is acceptable to all channel peers on the
1110         /// blinded path from the introduction node to the recipient, accounting for any fees, i.e., as
1111         /// seen by the recipient.
1112         pub htlc_minimum_msat: u64,
1113
1114         /// The maximum HTLC value (in millisatoshi) that is acceptable to all channel peers on the
1115         /// blinded path from the introduction node to the recipient, accounting for any fees, i.e., as
1116         /// seen by the recipient.
1117         pub htlc_maximum_msat: u64,
1118
1119         /// Features set in `encrypted_data_tlv` for the `encrypted_recipient_data` TLV record in an
1120         /// onion payload.
1121         pub features: BlindedHopFeatures,
1122 }
1123
1124 impl_writeable!(BlindedPayInfo, {
1125         fee_base_msat,
1126         fee_proportional_millionths,
1127         cltv_expiry_delta,
1128         htlc_minimum_msat,
1129         htlc_maximum_msat,
1130         features
1131 });
1132
1133 /// Wire representation for an on-chain fallback address.
1134 #[derive(Clone, Debug, PartialEq)]
1135 pub(super) struct FallbackAddress {
1136         version: u8,
1137         program: Vec<u8>,
1138 }
1139
1140 impl_writeable!(FallbackAddress, { version, program });
1141
1142 type FullInvoiceTlvStream =
1143         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream, SignatureTlvStream);
1144
1145 type FullInvoiceTlvStreamRef<'a> = (
1146         PayerTlvStreamRef<'a>,
1147         OfferTlvStreamRef<'a>,
1148         InvoiceRequestTlvStreamRef<'a>,
1149         InvoiceTlvStreamRef<'a>,
1150         SignatureTlvStreamRef<'a>,
1151 );
1152
1153 impl SeekReadable for FullInvoiceTlvStream {
1154         fn read<R: io::Read + io::Seek>(r: &mut R) -> Result<Self, DecodeError> {
1155                 let payer = SeekReadable::read(r)?;
1156                 let offer = SeekReadable::read(r)?;
1157                 let invoice_request = SeekReadable::read(r)?;
1158                 let invoice = SeekReadable::read(r)?;
1159                 let signature = SeekReadable::read(r)?;
1160
1161                 Ok((payer, offer, invoice_request, invoice, signature))
1162         }
1163 }
1164
1165 type PartialInvoiceTlvStream =
1166         (PayerTlvStream, OfferTlvStream, InvoiceRequestTlvStream, InvoiceTlvStream);
1167
1168 type PartialInvoiceTlvStreamRef<'a> = (
1169         PayerTlvStreamRef<'a>,
1170         OfferTlvStreamRef<'a>,
1171         InvoiceRequestTlvStreamRef<'a>,
1172         InvoiceTlvStreamRef<'a>,
1173 );
1174
1175 impl SeekReadable for PartialInvoiceTlvStream {
1176         fn read<R: io::Read + io::Seek>(r: &mut R) -> Result<Self, DecodeError> {
1177                 let payer = SeekReadable::read(r)?;
1178                 let offer = SeekReadable::read(r)?;
1179                 let invoice_request = SeekReadable::read(r)?;
1180                 let invoice = SeekReadable::read(r)?;
1181
1182                 Ok((payer, offer, invoice_request, invoice))
1183         }
1184 }
1185
1186 impl TryFrom<ParsedMessage<FullInvoiceTlvStream>> for Bolt12Invoice {
1187         type Error = Bolt12ParseError;
1188
1189         fn try_from(invoice: ParsedMessage<FullInvoiceTlvStream>) -> Result<Self, Self::Error> {
1190                 let ParsedMessage { bytes, tlv_stream } = invoice;
1191                 let (
1192                         payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream,
1193                         SignatureTlvStream { signature },
1194                 ) = tlv_stream;
1195                 let contents = InvoiceContents::try_from(
1196                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream, invoice_tlv_stream)
1197                 )?;
1198
1199                 let signature = match signature {
1200                         None => return Err(Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSignature)),
1201                         Some(signature) => signature,
1202                 };
1203                 let tagged_hash = TaggedHash::new(SIGNATURE_TAG, &bytes);
1204                 let pubkey = contents.fields().signing_pubkey;
1205                 merkle::verify_signature(&signature, &tagged_hash, pubkey)?;
1206
1207                 Ok(Bolt12Invoice { bytes, contents, signature, tagged_hash })
1208         }
1209 }
1210
1211 impl TryFrom<PartialInvoiceTlvStream> for InvoiceContents {
1212         type Error = Bolt12SemanticError;
1213
1214         fn try_from(tlv_stream: PartialInvoiceTlvStream) -> Result<Self, Self::Error> {
1215                 let (
1216                         payer_tlv_stream,
1217                         offer_tlv_stream,
1218                         invoice_request_tlv_stream,
1219                         InvoiceTlvStream {
1220                                 paths, blindedpay, created_at, relative_expiry, payment_hash, amount, fallbacks,
1221                                 features, node_id,
1222                         },
1223                 ) = tlv_stream;
1224
1225                 let payment_paths = match (blindedpay, paths) {
1226                         (_, None) => return Err(Bolt12SemanticError::MissingPaths),
1227                         (None, _) => return Err(Bolt12SemanticError::InvalidPayInfo),
1228                         (_, Some(paths)) if paths.is_empty() => return Err(Bolt12SemanticError::MissingPaths),
1229                         (Some(blindedpay), Some(paths)) if paths.len() != blindedpay.len() => {
1230                                 return Err(Bolt12SemanticError::InvalidPayInfo);
1231                         },
1232                         (Some(blindedpay), Some(paths)) => {
1233                                 blindedpay.into_iter().zip(paths.into_iter()).collect::<Vec<_>>()
1234                         },
1235                 };
1236
1237                 let created_at = match created_at {
1238                         None => return Err(Bolt12SemanticError::MissingCreationTime),
1239                         Some(timestamp) => Duration::from_secs(timestamp),
1240                 };
1241
1242                 let relative_expiry = relative_expiry
1243                         .map(Into::<u64>::into)
1244                         .map(Duration::from_secs);
1245
1246                 let payment_hash = match payment_hash {
1247                         None => return Err(Bolt12SemanticError::MissingPaymentHash),
1248                         Some(payment_hash) => payment_hash,
1249                 };
1250
1251                 let amount_msats = match amount {
1252                         None => return Err(Bolt12SemanticError::MissingAmount),
1253                         Some(amount) => amount,
1254                 };
1255
1256                 let features = features.unwrap_or_else(Bolt12InvoiceFeatures::empty);
1257
1258                 let signing_pubkey = match node_id {
1259                         None => return Err(Bolt12SemanticError::MissingSigningPubkey),
1260                         Some(node_id) => node_id,
1261                 };
1262
1263                 let fields = InvoiceFields {
1264                         payment_paths, created_at, relative_expiry, payment_hash, amount_msats, fallbacks,
1265                         features, signing_pubkey,
1266                 };
1267
1268                 match offer_tlv_stream.node_id {
1269                         Some(expected_signing_pubkey) => {
1270                                 if fields.signing_pubkey != expected_signing_pubkey {
1271                                         return Err(Bolt12SemanticError::InvalidSigningPubkey);
1272                                 }
1273
1274                                 let invoice_request = InvoiceRequestContents::try_from(
1275                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
1276                                 )?;
1277                                 Ok(InvoiceContents::ForOffer { invoice_request, fields })
1278                         },
1279                         None => {
1280                                 let refund = RefundContents::try_from(
1281                                         (payer_tlv_stream, offer_tlv_stream, invoice_request_tlv_stream)
1282                                 )?;
1283                                 Ok(InvoiceContents::ForRefund { refund, fields })
1284                         },
1285                 }
1286         }
1287 }
1288
1289 #[cfg(test)]
1290 mod tests {
1291         use super::{Bolt12Invoice, DEFAULT_RELATIVE_EXPIRY, FallbackAddress, FullInvoiceTlvStreamRef, InvoiceTlvStreamRef, SIGNATURE_TAG, UnsignedBolt12Invoice};
1292
1293         use bitcoin::blockdata::constants::ChainHash;
1294         use bitcoin::blockdata::script::ScriptBuf;
1295         use bitcoin::hashes::Hash;
1296         use bitcoin::network::constants::Network;
1297         use bitcoin::secp256k1::{Message, Secp256k1, XOnlyPublicKey, self};
1298         use bitcoin::address::{Address, Payload, WitnessProgram, WitnessVersion};
1299         use bitcoin::key::TweakedPublicKey;
1300         use core::convert::TryFrom;
1301         use core::time::Duration;
1302         use crate::blinded_path::{BlindedHop, BlindedPath};
1303         use crate::sign::KeyMaterial;
1304         use crate::ln::features::{Bolt12InvoiceFeatures, InvoiceRequestFeatures, OfferFeatures};
1305         use crate::ln::inbound_payment::ExpandedKey;
1306         use crate::ln::msgs::DecodeError;
1307         use crate::offers::invoice_request::InvoiceRequestTlvStreamRef;
1308         use crate::offers::merkle::{SignError, SignatureTlvStreamRef, TaggedHash, self};
1309         use crate::offers::offer::{Amount, OfferTlvStreamRef, Quantity};
1310         #[cfg(not(c_bindings))]
1311         use {
1312                 crate::offers::offer::OfferBuilder,
1313         };
1314         #[cfg(c_bindings)]
1315         use {
1316                 crate::offers::offer::OfferWithExplicitMetadataBuilder as OfferBuilder,
1317         };
1318         use crate::offers::parse::{Bolt12ParseError, Bolt12SemanticError};
1319         use crate::offers::payer::PayerTlvStreamRef;
1320         use crate::offers::refund::RefundBuilder;
1321         use crate::offers::test_utils::*;
1322         use crate::util::ser::{BigSize, Iterable, Writeable};
1323         use crate::util::string::PrintableString;
1324
1325         trait ToBytes {
1326                 fn to_bytes(&self) -> Vec<u8>;
1327         }
1328
1329         impl<'a> ToBytes for FullInvoiceTlvStreamRef<'a> {
1330                 fn to_bytes(&self) -> Vec<u8> {
1331                         let mut buffer = Vec::new();
1332                         self.0.write(&mut buffer).unwrap();
1333                         self.1.write(&mut buffer).unwrap();
1334                         self.2.write(&mut buffer).unwrap();
1335                         self.3.write(&mut buffer).unwrap();
1336                         self.4.write(&mut buffer).unwrap();
1337                         buffer
1338                 }
1339         }
1340
1341         #[test]
1342         fn builds_invoice_for_offer_with_defaults() {
1343                 let payment_paths = payment_paths();
1344                 let payment_hash = payment_hash();
1345                 let now = now();
1346                 let unsigned_invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1347                         .amount_msats(1000)
1348                         .build().unwrap()
1349                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1350                         .build().unwrap()
1351                         .sign(payer_sign).unwrap()
1352                         .respond_with_no_std(payment_paths.clone(), payment_hash, now).unwrap()
1353                         .build().unwrap();
1354
1355                 let mut buffer = Vec::new();
1356                 unsigned_invoice.write(&mut buffer).unwrap();
1357
1358                 assert_eq!(unsigned_invoice.bytes, buffer.as_slice());
1359                 assert_eq!(unsigned_invoice.payer_metadata(), &[1; 32]);
1360                 assert_eq!(unsigned_invoice.offer_chains(), Some(vec![ChainHash::using_genesis_block(Network::Bitcoin)]));
1361                 assert_eq!(unsigned_invoice.metadata(), None);
1362                 assert_eq!(unsigned_invoice.amount(), Some(&Amount::Bitcoin { amount_msats: 1000 }));
1363                 assert_eq!(unsigned_invoice.description(), PrintableString("foo"));
1364                 assert_eq!(unsigned_invoice.offer_features(), Some(&OfferFeatures::empty()));
1365                 assert_eq!(unsigned_invoice.absolute_expiry(), None);
1366                 assert_eq!(unsigned_invoice.message_paths(), &[]);
1367                 assert_eq!(unsigned_invoice.issuer(), None);
1368                 assert_eq!(unsigned_invoice.supported_quantity(), Some(Quantity::One));
1369                 assert_eq!(unsigned_invoice.signing_pubkey(), recipient_pubkey());
1370                 assert_eq!(unsigned_invoice.chain(), ChainHash::using_genesis_block(Network::Bitcoin));
1371                 assert_eq!(unsigned_invoice.amount_msats(), 1000);
1372                 assert_eq!(unsigned_invoice.invoice_request_features(), &InvoiceRequestFeatures::empty());
1373                 assert_eq!(unsigned_invoice.quantity(), None);
1374                 assert_eq!(unsigned_invoice.payer_id(), payer_pubkey());
1375                 assert_eq!(unsigned_invoice.payer_note(), None);
1376                 assert_eq!(unsigned_invoice.payment_paths(), payment_paths.as_slice());
1377                 assert_eq!(unsigned_invoice.created_at(), now);
1378                 assert_eq!(unsigned_invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
1379                 #[cfg(feature = "std")]
1380                 assert!(!unsigned_invoice.is_expired());
1381                 assert_eq!(unsigned_invoice.payment_hash(), payment_hash);
1382                 assert_eq!(unsigned_invoice.amount_msats(), 1000);
1383                 assert_eq!(unsigned_invoice.fallbacks(), vec![]);
1384                 assert_eq!(unsigned_invoice.invoice_features(), &Bolt12InvoiceFeatures::empty());
1385                 assert_eq!(unsigned_invoice.signing_pubkey(), recipient_pubkey());
1386
1387                 match UnsignedBolt12Invoice::try_from(buffer) {
1388                         Err(e) => panic!("error parsing unsigned invoice: {:?}", e),
1389                         Ok(parsed) => {
1390                                 assert_eq!(parsed.bytes, unsigned_invoice.bytes);
1391                                 assert_eq!(parsed.tagged_hash, unsigned_invoice.tagged_hash);
1392                         },
1393                 }
1394
1395                 let invoice = unsigned_invoice.sign(recipient_sign).unwrap();
1396
1397                 let mut buffer = Vec::new();
1398                 invoice.write(&mut buffer).unwrap();
1399
1400                 assert_eq!(invoice.bytes, buffer.as_slice());
1401                 assert_eq!(invoice.payer_metadata(), &[1; 32]);
1402                 assert_eq!(invoice.offer_chains(), Some(vec![ChainHash::using_genesis_block(Network::Bitcoin)]));
1403                 assert_eq!(invoice.metadata(), None);
1404                 assert_eq!(invoice.amount(), Some(&Amount::Bitcoin { amount_msats: 1000 }));
1405                 assert_eq!(invoice.description(), PrintableString("foo"));
1406                 assert_eq!(invoice.offer_features(), Some(&OfferFeatures::empty()));
1407                 assert_eq!(invoice.absolute_expiry(), None);
1408                 assert_eq!(invoice.message_paths(), &[]);
1409                 assert_eq!(invoice.issuer(), None);
1410                 assert_eq!(invoice.supported_quantity(), Some(Quantity::One));
1411                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
1412                 assert_eq!(invoice.chain(), ChainHash::using_genesis_block(Network::Bitcoin));
1413                 assert_eq!(invoice.amount_msats(), 1000);
1414                 assert_eq!(invoice.invoice_request_features(), &InvoiceRequestFeatures::empty());
1415                 assert_eq!(invoice.quantity(), None);
1416                 assert_eq!(invoice.payer_id(), payer_pubkey());
1417                 assert_eq!(invoice.payer_note(), None);
1418                 assert_eq!(invoice.payment_paths(), payment_paths.as_slice());
1419                 assert_eq!(invoice.created_at(), now);
1420                 assert_eq!(invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
1421                 #[cfg(feature = "std")]
1422                 assert!(!invoice.is_expired());
1423                 assert_eq!(invoice.payment_hash(), payment_hash);
1424                 assert_eq!(invoice.amount_msats(), 1000);
1425                 assert_eq!(invoice.fallbacks(), vec![]);
1426                 assert_eq!(invoice.invoice_features(), &Bolt12InvoiceFeatures::empty());
1427                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
1428
1429                 let message = TaggedHash::new(SIGNATURE_TAG, &invoice.bytes);
1430                 assert!(merkle::verify_signature(&invoice.signature, &message, recipient_pubkey()).is_ok());
1431
1432                 let digest = Message::from_slice(&invoice.signable_hash()).unwrap();
1433                 let pubkey = recipient_pubkey().into();
1434                 let secp_ctx = Secp256k1::verification_only();
1435                 assert!(secp_ctx.verify_schnorr(&invoice.signature, &digest, &pubkey).is_ok());
1436
1437                 assert_eq!(
1438                         invoice.as_tlv_stream(),
1439                         (
1440                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
1441                                 OfferTlvStreamRef {
1442                                         chains: None,
1443                                         metadata: None,
1444                                         currency: None,
1445                                         amount: Some(1000),
1446                                         description: Some(&String::from("foo")),
1447                                         features: None,
1448                                         absolute_expiry: None,
1449                                         paths: None,
1450                                         issuer: None,
1451                                         quantity_max: None,
1452                                         node_id: Some(&recipient_pubkey()),
1453                                 },
1454                                 InvoiceRequestTlvStreamRef {
1455                                         chain: None,
1456                                         amount: None,
1457                                         features: None,
1458                                         quantity: None,
1459                                         payer_id: Some(&payer_pubkey()),
1460                                         payer_note: None,
1461                                 },
1462                                 InvoiceTlvStreamRef {
1463                                         paths: Some(Iterable(payment_paths.iter().map(|(_, path)| path))),
1464                                         blindedpay: Some(Iterable(payment_paths.iter().map(|(payinfo, _)| payinfo))),
1465                                         created_at: Some(now.as_secs()),
1466                                         relative_expiry: None,
1467                                         payment_hash: Some(&payment_hash),
1468                                         amount: Some(1000),
1469                                         fallbacks: None,
1470                                         features: None,
1471                                         node_id: Some(&recipient_pubkey()),
1472                                 },
1473                                 SignatureTlvStreamRef { signature: Some(&invoice.signature()) },
1474                         ),
1475                 );
1476
1477                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1478                         panic!("error parsing invoice: {:?}", e);
1479                 }
1480         }
1481
1482         #[test]
1483         fn builds_invoice_for_refund_with_defaults() {
1484                 let payment_paths = payment_paths();
1485                 let payment_hash = payment_hash();
1486                 let now = now();
1487                 let invoice = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1488                         .build().unwrap()
1489                         .respond_with_no_std(payment_paths.clone(), payment_hash, recipient_pubkey(), now)
1490                         .unwrap()
1491                         .build().unwrap()
1492                         .sign(recipient_sign).unwrap();
1493
1494                 let mut buffer = Vec::new();
1495                 invoice.write(&mut buffer).unwrap();
1496
1497                 assert_eq!(invoice.bytes, buffer.as_slice());
1498                 assert_eq!(invoice.payer_metadata(), &[1; 32]);
1499                 assert_eq!(invoice.offer_chains(), None);
1500                 assert_eq!(invoice.metadata(), None);
1501                 assert_eq!(invoice.amount(), None);
1502                 assert_eq!(invoice.description(), PrintableString("foo"));
1503                 assert_eq!(invoice.offer_features(), None);
1504                 assert_eq!(invoice.absolute_expiry(), None);
1505                 assert_eq!(invoice.message_paths(), &[]);
1506                 assert_eq!(invoice.issuer(), None);
1507                 assert_eq!(invoice.supported_quantity(), None);
1508                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
1509                 assert_eq!(invoice.chain(), ChainHash::using_genesis_block(Network::Bitcoin));
1510                 assert_eq!(invoice.amount_msats(), 1000);
1511                 assert_eq!(invoice.invoice_request_features(), &InvoiceRequestFeatures::empty());
1512                 assert_eq!(invoice.quantity(), None);
1513                 assert_eq!(invoice.payer_id(), payer_pubkey());
1514                 assert_eq!(invoice.payer_note(), None);
1515                 assert_eq!(invoice.payment_paths(), payment_paths.as_slice());
1516                 assert_eq!(invoice.created_at(), now);
1517                 assert_eq!(invoice.relative_expiry(), DEFAULT_RELATIVE_EXPIRY);
1518                 #[cfg(feature = "std")]
1519                 assert!(!invoice.is_expired());
1520                 assert_eq!(invoice.payment_hash(), payment_hash);
1521                 assert_eq!(invoice.amount_msats(), 1000);
1522                 assert_eq!(invoice.fallbacks(), vec![]);
1523                 assert_eq!(invoice.invoice_features(), &Bolt12InvoiceFeatures::empty());
1524                 assert_eq!(invoice.signing_pubkey(), recipient_pubkey());
1525
1526                 let message = TaggedHash::new(SIGNATURE_TAG, &invoice.bytes);
1527                 assert!(merkle::verify_signature(&invoice.signature, &message, recipient_pubkey()).is_ok());
1528
1529                 assert_eq!(
1530                         invoice.as_tlv_stream(),
1531                         (
1532                                 PayerTlvStreamRef { metadata: Some(&vec![1; 32]) },
1533                                 OfferTlvStreamRef {
1534                                         chains: None,
1535                                         metadata: None,
1536                                         currency: None,
1537                                         amount: None,
1538                                         description: Some(&String::from("foo")),
1539                                         features: None,
1540                                         absolute_expiry: None,
1541                                         paths: None,
1542                                         issuer: None,
1543                                         quantity_max: None,
1544                                         node_id: None,
1545                                 },
1546                                 InvoiceRequestTlvStreamRef {
1547                                         chain: None,
1548                                         amount: Some(1000),
1549                                         features: None,
1550                                         quantity: None,
1551                                         payer_id: Some(&payer_pubkey()),
1552                                         payer_note: None,
1553                                 },
1554                                 InvoiceTlvStreamRef {
1555                                         paths: Some(Iterable(payment_paths.iter().map(|(_, path)| path))),
1556                                         blindedpay: Some(Iterable(payment_paths.iter().map(|(payinfo, _)| payinfo))),
1557                                         created_at: Some(now.as_secs()),
1558                                         relative_expiry: None,
1559                                         payment_hash: Some(&payment_hash),
1560                                         amount: Some(1000),
1561                                         fallbacks: None,
1562                                         features: None,
1563                                         node_id: Some(&recipient_pubkey()),
1564                                 },
1565                                 SignatureTlvStreamRef { signature: Some(&invoice.signature()) },
1566                         ),
1567                 );
1568
1569                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1570                         panic!("error parsing invoice: {:?}", e);
1571                 }
1572         }
1573
1574         #[cfg(feature = "std")]
1575         #[test]
1576         fn builds_invoice_from_offer_with_expiration() {
1577                 let future_expiry = Duration::from_secs(u64::max_value());
1578                 let past_expiry = Duration::from_secs(0);
1579
1580                 if let Err(e) = OfferBuilder::new("foo".into(), recipient_pubkey())
1581                         .amount_msats(1000)
1582                         .absolute_expiry(future_expiry)
1583                         .build().unwrap()
1584                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1585                         .build().unwrap()
1586                         .sign(payer_sign).unwrap()
1587                         .respond_with(payment_paths(), payment_hash())
1588                         .unwrap()
1589                         .build()
1590                 {
1591                         panic!("error building invoice: {:?}", e);
1592                 }
1593
1594                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1595                         .amount_msats(1000)
1596                         .absolute_expiry(past_expiry)
1597                         .build().unwrap()
1598                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1599                         .build_unchecked()
1600                         .sign(payer_sign).unwrap()
1601                         .respond_with(payment_paths(), payment_hash())
1602                         .unwrap()
1603                         .build()
1604                 {
1605                         Ok(_) => panic!("expected error"),
1606                         Err(e) => assert_eq!(e, Bolt12SemanticError::AlreadyExpired),
1607                 }
1608         }
1609
1610         #[cfg(feature = "std")]
1611         #[test]
1612         fn builds_invoice_from_refund_with_expiration() {
1613                 let future_expiry = Duration::from_secs(u64::max_value());
1614                 let past_expiry = Duration::from_secs(0);
1615
1616                 if let Err(e) = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1617                         .absolute_expiry(future_expiry)
1618                         .build().unwrap()
1619                         .respond_with(payment_paths(), payment_hash(), recipient_pubkey())
1620                         .unwrap()
1621                         .build()
1622                 {
1623                         panic!("error building invoice: {:?}", e);
1624                 }
1625
1626                 match RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1627                         .absolute_expiry(past_expiry)
1628                         .build().unwrap()
1629                         .respond_with(payment_paths(), payment_hash(), recipient_pubkey())
1630                         .unwrap()
1631                         .build()
1632                 {
1633                         Ok(_) => panic!("expected error"),
1634                         Err(e) => assert_eq!(e, Bolt12SemanticError::AlreadyExpired),
1635                 }
1636         }
1637
1638         #[test]
1639         fn builds_invoice_from_offer_using_derived_keys() {
1640                 let desc = "foo".to_string();
1641                 let node_id = recipient_pubkey();
1642                 let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
1643                 let entropy = FixedEntropy {};
1644                 let secp_ctx = Secp256k1::new();
1645
1646                 let blinded_path = BlindedPath {
1647                         introduction_node_id: pubkey(40),
1648                         blinding_point: pubkey(41),
1649                         blinded_hops: vec![
1650                                 BlindedHop { blinded_node_id: pubkey(42), encrypted_payload: vec![0; 43] },
1651                                 BlindedHop { blinded_node_id: node_id, encrypted_payload: vec![0; 44] },
1652                         ],
1653                 };
1654
1655                 #[cfg(c_bindings)]
1656                 use crate::offers::offer::OfferWithDerivedMetadataBuilder as OfferBuilder;
1657                 let offer = OfferBuilder
1658                         ::deriving_signing_pubkey(desc, node_id, &expanded_key, &entropy, &secp_ctx)
1659                         .amount_msats(1000)
1660                         .path(blinded_path)
1661                         .build().unwrap();
1662                 let invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1663                         .build().unwrap()
1664                         .sign(payer_sign).unwrap();
1665
1666                 if let Err(e) = invoice_request.clone()
1667                         .verify(&expanded_key, &secp_ctx).unwrap()
1668                         .respond_using_derived_keys_no_std(payment_paths(), payment_hash(), now()).unwrap()
1669                         .build_and_sign(&secp_ctx)
1670                 {
1671                         panic!("error building invoice: {:?}", e);
1672                 }
1673
1674                 let expanded_key = ExpandedKey::new(&KeyMaterial([41; 32]));
1675                 assert!(invoice_request.verify(&expanded_key, &secp_ctx).is_err());
1676
1677                 let desc = "foo".to_string();
1678                 let offer = OfferBuilder
1679                         ::deriving_signing_pubkey(desc, node_id, &expanded_key, &entropy, &secp_ctx)
1680                         .amount_msats(1000)
1681                         // Omit the path so that node_id is used for the signing pubkey instead of deriving
1682                         .build().unwrap();
1683                 let invoice_request = offer.request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1684                         .build().unwrap()
1685                         .sign(payer_sign).unwrap();
1686
1687                 match invoice_request
1688                         .verify(&expanded_key, &secp_ctx).unwrap()
1689                         .respond_using_derived_keys_no_std(payment_paths(), payment_hash(), now())
1690                 {
1691                         Ok(_) => panic!("expected error"),
1692                         Err(e) => assert_eq!(e, Bolt12SemanticError::InvalidMetadata),
1693                 }
1694         }
1695
1696         #[test]
1697         fn builds_invoice_from_refund_using_derived_keys() {
1698                 let expanded_key = ExpandedKey::new(&KeyMaterial([42; 32]));
1699                 let entropy = FixedEntropy {};
1700                 let secp_ctx = Secp256k1::new();
1701
1702                 let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
1703                         .build().unwrap();
1704
1705                 if let Err(e) = refund
1706                         .respond_using_derived_keys_no_std(
1707                                 payment_paths(), payment_hash(), now(), &expanded_key, &entropy
1708                         )
1709                         .unwrap()
1710                         .build_and_sign(&secp_ctx)
1711                 {
1712                         panic!("error building invoice: {:?}", e);
1713                 }
1714         }
1715
1716         #[test]
1717         fn builds_invoice_with_relative_expiry() {
1718                 let now = now();
1719                 let one_hour = Duration::from_secs(3600);
1720
1721                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1722                         .amount_msats(1000)
1723                         .build().unwrap()
1724                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1725                         .build().unwrap()
1726                         .sign(payer_sign).unwrap()
1727                         .respond_with_no_std(payment_paths(), payment_hash(), now).unwrap()
1728                         .relative_expiry(one_hour.as_secs() as u32)
1729                         .build().unwrap()
1730                         .sign(recipient_sign).unwrap();
1731                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1732                 #[cfg(feature = "std")]
1733                 assert!(!invoice.is_expired());
1734                 assert_eq!(invoice.relative_expiry(), one_hour);
1735                 assert_eq!(tlv_stream.relative_expiry, Some(one_hour.as_secs() as u32));
1736
1737                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1738                         .amount_msats(1000)
1739                         .build().unwrap()
1740                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1741                         .build().unwrap()
1742                         .sign(payer_sign).unwrap()
1743                         .respond_with_no_std(payment_paths(), payment_hash(), now - one_hour).unwrap()
1744                         .relative_expiry(one_hour.as_secs() as u32 - 1)
1745                         .build().unwrap()
1746                         .sign(recipient_sign).unwrap();
1747                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1748                 #[cfg(feature = "std")]
1749                 assert!(invoice.is_expired());
1750                 assert_eq!(invoice.relative_expiry(), one_hour - Duration::from_secs(1));
1751                 assert_eq!(tlv_stream.relative_expiry, Some(one_hour.as_secs() as u32 - 1));
1752         }
1753
1754         #[test]
1755         fn builds_invoice_with_amount_from_request() {
1756                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1757                         .amount_msats(1000)
1758                         .build().unwrap()
1759                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1760                         .amount_msats(1001).unwrap()
1761                         .build().unwrap()
1762                         .sign(payer_sign).unwrap()
1763                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1764                         .build().unwrap()
1765                         .sign(recipient_sign).unwrap();
1766                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1767                 assert_eq!(invoice.amount_msats(), 1001);
1768                 assert_eq!(tlv_stream.amount, Some(1001));
1769         }
1770
1771         #[test]
1772         fn builds_invoice_with_quantity_from_request() {
1773                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1774                         .amount_msats(1000)
1775                         .supported_quantity(Quantity::Unbounded)
1776                         .build().unwrap()
1777                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1778                         .quantity(2).unwrap()
1779                         .build().unwrap()
1780                         .sign(payer_sign).unwrap()
1781                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1782                         .build().unwrap()
1783                         .sign(recipient_sign).unwrap();
1784                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1785                 assert_eq!(invoice.amount_msats(), 2000);
1786                 assert_eq!(tlv_stream.amount, Some(2000));
1787
1788                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1789                         .amount_msats(1000)
1790                         .supported_quantity(Quantity::Unbounded)
1791                         .build().unwrap()
1792                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1793                         .quantity(u64::max_value()).unwrap()
1794                         .build_unchecked()
1795                         .sign(payer_sign).unwrap()
1796                         .respond_with_no_std(payment_paths(), payment_hash(), now())
1797                 {
1798                         Ok(_) => panic!("expected error"),
1799                         Err(e) => assert_eq!(e, Bolt12SemanticError::InvalidAmount),
1800                 }
1801         }
1802
1803         #[test]
1804         fn builds_invoice_with_fallback_address() {
1805                 let script = ScriptBuf::new();
1806                 let pubkey = bitcoin::key::PublicKey::new(recipient_pubkey());
1807                 let x_only_pubkey = XOnlyPublicKey::from_keypair(&recipient_keys()).0;
1808                 let tweaked_pubkey = TweakedPublicKey::dangerous_assume_tweaked(x_only_pubkey);
1809
1810                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1811                         .amount_msats(1000)
1812                         .build().unwrap()
1813                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1814                         .build().unwrap()
1815                         .sign(payer_sign).unwrap()
1816                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1817                         .fallback_v0_p2wsh(&script.wscript_hash())
1818                         .fallback_v0_p2wpkh(&pubkey.wpubkey_hash().unwrap())
1819                         .fallback_v1_p2tr_tweaked(&tweaked_pubkey)
1820                         .build().unwrap()
1821                         .sign(recipient_sign).unwrap();
1822                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1823                 assert_eq!(
1824                         invoice.fallbacks(),
1825                         vec![
1826                                 Address::p2wsh(&script, Network::Bitcoin),
1827                                 Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap(),
1828                                 Address::p2tr_tweaked(tweaked_pubkey, Network::Bitcoin),
1829                         ],
1830                 );
1831                 assert_eq!(
1832                         tlv_stream.fallbacks,
1833                         Some(&vec![
1834                                 FallbackAddress {
1835                                         version: WitnessVersion::V0.to_num(),
1836                                         program: Vec::from(script.wscript_hash().to_byte_array()),
1837                                 },
1838                                 FallbackAddress {
1839                                         version: WitnessVersion::V0.to_num(),
1840                                         program: Vec::from(pubkey.wpubkey_hash().unwrap().to_byte_array()),
1841                                 },
1842                                 FallbackAddress {
1843                                         version: WitnessVersion::V1.to_num(),
1844                                         program: Vec::from(&tweaked_pubkey.serialize()[..]),
1845                                 },
1846                         ])
1847                 );
1848         }
1849
1850         #[test]
1851         fn builds_invoice_with_allow_mpp() {
1852                 let mut features = Bolt12InvoiceFeatures::empty();
1853                 features.set_basic_mpp_optional();
1854
1855                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1856                         .amount_msats(1000)
1857                         .build().unwrap()
1858                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1859                         .build().unwrap()
1860                         .sign(payer_sign).unwrap()
1861                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1862                         .allow_mpp()
1863                         .build().unwrap()
1864                         .sign(recipient_sign).unwrap();
1865                 let (_, _, _, tlv_stream, _) = invoice.as_tlv_stream();
1866                 assert_eq!(invoice.invoice_features(), &features);
1867                 assert_eq!(tlv_stream.features, Some(&features));
1868         }
1869
1870         #[test]
1871         fn fails_signing_invoice() {
1872                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1873                         .amount_msats(1000)
1874                         .build().unwrap()
1875                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1876                         .build().unwrap()
1877                         .sign(payer_sign).unwrap()
1878                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1879                         .build().unwrap()
1880                         .sign(|_| Err(()))
1881                 {
1882                         Ok(_) => panic!("expected error"),
1883                         Err(e) => assert_eq!(e, SignError::Signing(())),
1884                 }
1885
1886                 match OfferBuilder::new("foo".into(), recipient_pubkey())
1887                         .amount_msats(1000)
1888                         .build().unwrap()
1889                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1890                         .build().unwrap()
1891                         .sign(payer_sign).unwrap()
1892                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1893                         .build().unwrap()
1894                         .sign(payer_sign)
1895                 {
1896                         Ok(_) => panic!("expected error"),
1897                         Err(e) => assert_eq!(e, SignError::Verification(secp256k1::Error::InvalidSignature)),
1898                 }
1899         }
1900
1901         #[test]
1902         fn parses_invoice_with_payment_paths() {
1903                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1904                         .amount_msats(1000)
1905                         .build().unwrap()
1906                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1907                         .build().unwrap()
1908                         .sign(payer_sign).unwrap()
1909                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1910                         .build().unwrap()
1911                         .sign(recipient_sign).unwrap();
1912
1913                 let mut buffer = Vec::new();
1914                 invoice.write(&mut buffer).unwrap();
1915
1916                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1917                         panic!("error parsing invoice: {:?}", e);
1918                 }
1919
1920                 let mut tlv_stream = invoice.as_tlv_stream();
1921                 tlv_stream.3.paths = None;
1922
1923                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1924                         Ok(_) => panic!("expected error"),
1925                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingPaths)),
1926                 }
1927
1928                 let mut tlv_stream = invoice.as_tlv_stream();
1929                 tlv_stream.3.blindedpay = None;
1930
1931                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1932                         Ok(_) => panic!("expected error"),
1933                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InvalidPayInfo)),
1934                 }
1935
1936                 let empty_payment_paths = vec![];
1937                 let mut tlv_stream = invoice.as_tlv_stream();
1938                 tlv_stream.3.paths = Some(Iterable(empty_payment_paths.iter().map(|(_, path)| path)));
1939
1940                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1941                         Ok(_) => panic!("expected error"),
1942                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingPaths)),
1943                 }
1944
1945                 let mut payment_paths = payment_paths();
1946                 payment_paths.pop();
1947                 let mut tlv_stream = invoice.as_tlv_stream();
1948                 tlv_stream.3.blindedpay = Some(Iterable(payment_paths.iter().map(|(payinfo, _)| payinfo)));
1949
1950                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1951                         Ok(_) => panic!("expected error"),
1952                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InvalidPayInfo)),
1953                 }
1954         }
1955
1956         #[test]
1957         fn parses_invoice_with_created_at() {
1958                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1959                         .amount_msats(1000)
1960                         .build().unwrap()
1961                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1962                         .build().unwrap()
1963                         .sign(payer_sign).unwrap()
1964                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1965                         .build().unwrap()
1966                         .sign(recipient_sign).unwrap();
1967
1968                 let mut buffer = Vec::new();
1969                 invoice.write(&mut buffer).unwrap();
1970
1971                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
1972                         panic!("error parsing invoice: {:?}", e);
1973                 }
1974
1975                 let mut tlv_stream = invoice.as_tlv_stream();
1976                 tlv_stream.3.created_at = None;
1977
1978                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
1979                         Ok(_) => panic!("expected error"),
1980                         Err(e) => {
1981                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingCreationTime));
1982                         },
1983                 }
1984         }
1985
1986         #[test]
1987         fn parses_invoice_with_relative_expiry() {
1988                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
1989                         .amount_msats(1000)
1990                         .build().unwrap()
1991                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
1992                         .build().unwrap()
1993                         .sign(payer_sign).unwrap()
1994                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
1995                         .relative_expiry(3600)
1996                         .build().unwrap()
1997                         .sign(recipient_sign).unwrap();
1998
1999                 let mut buffer = Vec::new();
2000                 invoice.write(&mut buffer).unwrap();
2001
2002                 match Bolt12Invoice::try_from(buffer) {
2003                         Ok(invoice) => assert_eq!(invoice.relative_expiry(), Duration::from_secs(3600)),
2004                         Err(e) => panic!("error parsing invoice: {:?}", e),
2005                 }
2006         }
2007
2008         #[test]
2009         fn parses_invoice_with_payment_hash() {
2010                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
2011                         .amount_msats(1000)
2012                         .build().unwrap()
2013                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2014                         .build().unwrap()
2015                         .sign(payer_sign).unwrap()
2016                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2017                         .build().unwrap()
2018                         .sign(recipient_sign).unwrap();
2019
2020                 let mut buffer = Vec::new();
2021                 invoice.write(&mut buffer).unwrap();
2022
2023                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
2024                         panic!("error parsing invoice: {:?}", e);
2025                 }
2026
2027                 let mut tlv_stream = invoice.as_tlv_stream();
2028                 tlv_stream.3.payment_hash = None;
2029
2030                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2031                         Ok(_) => panic!("expected error"),
2032                         Err(e) => {
2033                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingPaymentHash));
2034                         },
2035                 }
2036         }
2037
2038         #[test]
2039         fn parses_invoice_with_amount() {
2040                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
2041                         .amount_msats(1000)
2042                         .build().unwrap()
2043                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2044                         .build().unwrap()
2045                         .sign(payer_sign).unwrap()
2046                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2047                         .build().unwrap()
2048                         .sign(recipient_sign).unwrap();
2049
2050                 let mut buffer = Vec::new();
2051                 invoice.write(&mut buffer).unwrap();
2052
2053                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
2054                         panic!("error parsing invoice: {:?}", e);
2055                 }
2056
2057                 let mut tlv_stream = invoice.as_tlv_stream();
2058                 tlv_stream.3.amount = None;
2059
2060                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2061                         Ok(_) => panic!("expected error"),
2062                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingAmount)),
2063                 }
2064         }
2065
2066         #[test]
2067         fn parses_invoice_with_allow_mpp() {
2068                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
2069                         .amount_msats(1000)
2070                         .build().unwrap()
2071                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2072                         .build().unwrap()
2073                         .sign(payer_sign).unwrap()
2074                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2075                         .allow_mpp()
2076                         .build().unwrap()
2077                         .sign(recipient_sign).unwrap();
2078
2079                 let mut buffer = Vec::new();
2080                 invoice.write(&mut buffer).unwrap();
2081
2082                 match Bolt12Invoice::try_from(buffer) {
2083                         Ok(invoice) => {
2084                                 let mut features = Bolt12InvoiceFeatures::empty();
2085                                 features.set_basic_mpp_optional();
2086                                 assert_eq!(invoice.invoice_features(), &features);
2087                         },
2088                         Err(e) => panic!("error parsing invoice: {:?}", e),
2089                 }
2090         }
2091
2092         #[test]
2093         fn parses_invoice_with_fallback_address() {
2094                 let script = ScriptBuf::new();
2095                 let pubkey = bitcoin::key::PublicKey::new(recipient_pubkey());
2096                 let x_only_pubkey = XOnlyPublicKey::from_keypair(&recipient_keys()).0;
2097                 let tweaked_pubkey = TweakedPublicKey::dangerous_assume_tweaked(x_only_pubkey);
2098
2099                 let offer = OfferBuilder::new("foo".into(), recipient_pubkey())
2100                         .amount_msats(1000)
2101                         .build().unwrap();
2102                 let invoice_request = offer
2103                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2104                         .build().unwrap()
2105                         .sign(payer_sign).unwrap();
2106                 let mut invoice_builder = invoice_request
2107                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2108                         .fallback_v0_p2wsh(&script.wscript_hash())
2109                         .fallback_v0_p2wpkh(&pubkey.wpubkey_hash().unwrap())
2110                         .fallback_v1_p2tr_tweaked(&tweaked_pubkey);
2111
2112                 // Only standard addresses will be included.
2113                 let fallbacks = invoice_builder.invoice.fields_mut().fallbacks.as_mut().unwrap();
2114                 // Non-standard addresses
2115                 fallbacks.push(FallbackAddress { version: 1, program: vec![0u8; 41] });
2116                 fallbacks.push(FallbackAddress { version: 2, program: vec![0u8; 1] });
2117                 fallbacks.push(FallbackAddress { version: 17, program: vec![0u8; 40] });
2118                 // Standard address
2119                 fallbacks.push(FallbackAddress { version: 1, program: vec![0u8; 33] });
2120                 fallbacks.push(FallbackAddress { version: 2, program: vec![0u8; 40] });
2121
2122                 let invoice = invoice_builder.build().unwrap().sign(recipient_sign).unwrap();
2123                 let mut buffer = Vec::new();
2124                 invoice.write(&mut buffer).unwrap();
2125
2126                 match Bolt12Invoice::try_from(buffer) {
2127                         Ok(invoice) => {
2128                                 let v1_witness_program = WitnessProgram::new(WitnessVersion::V1, vec![0u8; 33]).unwrap();
2129                                 let v2_witness_program = WitnessProgram::new(WitnessVersion::V2, vec![0u8; 40]).unwrap();
2130                                 assert_eq!(
2131                                         invoice.fallbacks(),
2132                                         vec![
2133                                                 Address::p2wsh(&script, Network::Bitcoin),
2134                                                 Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap(),
2135                                                 Address::p2tr_tweaked(tweaked_pubkey, Network::Bitcoin),
2136                                                 Address::new(Network::Bitcoin, Payload::WitnessProgram(v1_witness_program)),
2137                                                 Address::new(Network::Bitcoin, Payload::WitnessProgram(v2_witness_program)),
2138                                         ],
2139                                 );
2140                         },
2141                         Err(e) => panic!("error parsing invoice: {:?}", e),
2142                 }
2143         }
2144
2145         #[test]
2146         fn parses_invoice_with_node_id() {
2147                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
2148                         .amount_msats(1000)
2149                         .build().unwrap()
2150                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2151                         .build().unwrap()
2152                         .sign(payer_sign).unwrap()
2153                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2154                         .build().unwrap()
2155                         .sign(recipient_sign).unwrap();
2156
2157                 let mut buffer = Vec::new();
2158                 invoice.write(&mut buffer).unwrap();
2159
2160                 if let Err(e) = Bolt12Invoice::try_from(buffer) {
2161                         panic!("error parsing invoice: {:?}", e);
2162                 }
2163
2164                 let mut tlv_stream = invoice.as_tlv_stream();
2165                 tlv_stream.3.node_id = None;
2166
2167                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2168                         Ok(_) => panic!("expected error"),
2169                         Err(e) => {
2170                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSigningPubkey));
2171                         },
2172                 }
2173
2174                 let invalid_pubkey = payer_pubkey();
2175                 let mut tlv_stream = invoice.as_tlv_stream();
2176                 tlv_stream.3.node_id = Some(&invalid_pubkey);
2177
2178                 match Bolt12Invoice::try_from(tlv_stream.to_bytes()) {
2179                         Ok(_) => panic!("expected error"),
2180                         Err(e) => {
2181                                 assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::InvalidSigningPubkey));
2182                         },
2183                 }
2184         }
2185
2186         #[test]
2187         fn fails_parsing_invoice_without_signature() {
2188                 let mut buffer = Vec::new();
2189                 OfferBuilder::new("foo".into(), recipient_pubkey())
2190                         .amount_msats(1000)
2191                         .build().unwrap()
2192                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2193                         .build().unwrap()
2194                         .sign(payer_sign).unwrap()
2195                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2196                         .build().unwrap()
2197                         .contents
2198                         .write(&mut buffer).unwrap();
2199
2200                 match Bolt12Invoice::try_from(buffer) {
2201                         Ok(_) => panic!("expected error"),
2202                         Err(e) => assert_eq!(e, Bolt12ParseError::InvalidSemantics(Bolt12SemanticError::MissingSignature)),
2203                 }
2204         }
2205
2206         #[test]
2207         fn fails_parsing_invoice_with_invalid_signature() {
2208                 let mut invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
2209                         .amount_msats(1000)
2210                         .build().unwrap()
2211                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2212                         .build().unwrap()
2213                         .sign(payer_sign).unwrap()
2214                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2215                         .build().unwrap()
2216                         .sign(recipient_sign).unwrap();
2217                 let last_signature_byte = invoice.bytes.last_mut().unwrap();
2218                 *last_signature_byte = last_signature_byte.wrapping_add(1);
2219
2220                 let mut buffer = Vec::new();
2221                 invoice.write(&mut buffer).unwrap();
2222
2223                 match Bolt12Invoice::try_from(buffer) {
2224                         Ok(_) => panic!("expected error"),
2225                         Err(e) => {
2226                                 assert_eq!(e, Bolt12ParseError::InvalidSignature(secp256k1::Error::InvalidSignature));
2227                         },
2228                 }
2229         }
2230
2231         #[test]
2232         fn fails_parsing_invoice_with_extra_tlv_records() {
2233                 let invoice = OfferBuilder::new("foo".into(), recipient_pubkey())
2234                         .amount_msats(1000)
2235                         .build().unwrap()
2236                         .request_invoice(vec![1; 32], payer_pubkey()).unwrap()
2237                         .build().unwrap()
2238                         .sign(payer_sign).unwrap()
2239                         .respond_with_no_std(payment_paths(), payment_hash(), now()).unwrap()
2240                         .build().unwrap()
2241                         .sign(recipient_sign).unwrap();
2242
2243                 let mut encoded_invoice = Vec::new();
2244                 invoice.write(&mut encoded_invoice).unwrap();
2245                 BigSize(1002).write(&mut encoded_invoice).unwrap();
2246                 BigSize(32).write(&mut encoded_invoice).unwrap();
2247                 [42u8; 32].write(&mut encoded_invoice).unwrap();
2248
2249                 match Bolt12Invoice::try_from(encoded_invoice) {
2250                         Ok(_) => panic!("expected error"),
2251                         Err(e) => assert_eq!(e, Bolt12ParseError::Decode(DecodeError::InvalidValue)),
2252                 }
2253         }
2254 }