//! Data structures and encoding for refunds.
//!
//! A [`Refund`] is an "offer for money" and is typically constructed by a merchant and presented
-//! directly to the customer. The recipient responds with an `Invoice` to be paid.
+//! directly to the customer. The recipient responds with an [`Invoice`] to be paid.
//!
//! This is an [`InvoiceRequest`] produced *not* in response to an [`Offer`].
//!
+//! [`Invoice`]: crate::offers::invoice::Invoice
//! [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
//! [`Offer`]: crate::offers::offer::Offer
//!
use core::str::FromStr;
use core::time::Duration;
use crate::io;
+use crate::ln::PaymentHash;
use crate::ln::features::InvoiceRequestFeatures;
use crate::ln::msgs::{DecodeError, MAX_VALUE_MSAT};
+use crate::offers::invoice::{BlindedPayInfo, InvoiceBuilder};
use crate::offers::invoice_request::{InvoiceRequestTlvStream, InvoiceRequestTlvStreamRef};
use crate::offers::offer::{OfferTlvStream, OfferTlvStreamRef};
use crate::offers::parse::{Bech32Encode, ParseError, ParsedMessage, SemanticError};
}
impl RefundBuilder {
- /// Creates a new builder for a refund using the [`Refund::payer_id`] for signing invoices. Use
- /// a different pubkey per refund to avoid correlating refunds.
+ /// Creates a new builder for a refund using the [`Refund::payer_id`] for the public node id to
+ /// send to if no [`Refund::paths`] are set. Otherwise, it may be a transient pubkey.
///
/// Additionally, sets the required [`Refund::description`], [`Refund::metadata`], and
/// [`Refund::amount_msats`].
}
let refund = RefundContents {
- payer: PayerContents(metadata), metadata: None, description, absolute_expiry: None,
- issuer: None, paths: None, chain: None, amount_msats,
- features: InvoiceRequestFeatures::empty(), payer_id, payer_note: None,
+ payer: PayerContents(metadata), description, absolute_expiry: None, issuer: None,
+ paths: None, chain: None, amount_msats, features: InvoiceRequestFeatures::empty(),
+ quantity: None, payer_id, payer_note: None,
};
Ok(RefundBuilder { refund })
self
}
+ /// Sets [`Refund::quantity`] of items. This is purely for informational purposes. It is useful
+ /// when the refund pertains to an [`Invoice`] that paid for more than one item from an
+ /// [`Offer`] as specified by [`InvoiceRequest::quantity`].
+ ///
+ /// Successive calls to this method will override the previous setting.
+ ///
+ /// [`Invoice`]: crate::offers::invoice::Invoice
+ /// [`InvoiceRequest::quantity`]: crate::offers::invoice_request::InvoiceRequest::quantity
+ /// [`Offer`]: crate::offers::offer::Offer
+ pub fn quantity(mut self, quantity: u64) -> Self {
+ self.refund.quantity = Some(quantity);
+ self
+ }
+
/// Sets the [`Refund::payer_note`].
///
/// Successive calls to this method will override the previous setting.
}
}
-/// A `Refund` is a request to send an `Invoice` without a preceding [`Offer`].
+#[cfg(test)]
+impl RefundBuilder {
+ fn features_unchecked(mut self, features: InvoiceRequestFeatures) -> Self {
+ self.refund.features = features;
+ self
+ }
+}
+
+/// A `Refund` is a request to send an [`Invoice`] without a preceding [`Offer`].
///
/// Typically, after an invoice is paid, the recipient may publish a refund allowing the sender to
/// recoup their funds. A refund may be used more generally as an "offer for money", such as with a
/// bitcoin ATM.
///
+/// [`Invoice`]: crate::offers::invoice::Invoice
/// [`Offer`]: crate::offers::offer::Offer
#[derive(Clone, Debug)]
pub struct Refund {
- bytes: Vec<u8>,
- contents: RefundContents,
+ pub(super) bytes: Vec<u8>,
+ pub(super) contents: RefundContents,
}
-/// The contents of a [`Refund`], which may be shared with an `Invoice`.
+/// The contents of a [`Refund`], which may be shared with an [`Invoice`].
+///
+/// [`Invoice`]: crate::offers::invoice::Invoice
#[derive(Clone, Debug)]
-struct RefundContents {
+pub(super) struct RefundContents {
payer: PayerContents,
// offer fields
- metadata: Option<Vec<u8>>,
description: String,
absolute_expiry: Option<Duration>,
issuer: Option<String>,
chain: Option<ChainHash>,
amount_msats: u64,
features: InvoiceRequestFeatures,
+ quantity: Option<u64>,
payer_id: PublicKey,
payer_note: Option<String>,
}
/// Whether the refund has expired.
#[cfg(feature = "std")]
pub fn is_expired(&self) -> bool {
- match self.absolute_expiry() {
- Some(seconds_from_epoch) => match SystemTime::UNIX_EPOCH.elapsed() {
- Ok(elapsed) => elapsed > seconds_from_epoch,
- Err(_) => false,
- },
- None => false,
- }
+ self.contents.is_expired()
}
/// The issuer of the refund, possibly beginning with `user@domain` or `domain`. Intended to be
&self.contents.features
}
- /// A possibly transient pubkey used to sign the refund.
+ /// The quantity of an item that refund is for.
+ pub fn quantity(&self) -> Option<u64> {
+ self.contents.quantity
+ }
+
+ /// A public node id to send to in the case where there are no [`paths`]. Otherwise, a possibly
+ /// transient pubkey.
+ ///
+ /// [`paths`]: Self::paths
pub fn payer_id(&self) -> PublicKey {
self.contents.payer_id
}
self.contents.payer_note.as_ref().map(|payer_note| PrintableString(payer_note.as_str()))
}
+ /// Creates an [`Invoice`] for the refund with the given required fields.
+ ///
+ /// Unless [`InvoiceBuilder::relative_expiry`] is set, the invoice will expire two hours after
+ /// calling this method in `std` builds. For `no-std` builds, a final [`Duration`] parameter
+ /// must be given, which is used to set [`Invoice::created_at`] since [`std::time::SystemTime`]
+ /// is not available.
+ ///
+ /// The caller is expected to remember the preimage of `payment_hash` in order to
+ /// claim a payment for the invoice.
+ ///
+ /// The `signing_pubkey` is required to sign the invoice since refunds are not in response to an
+ /// offer, which does have a `signing_pubkey`.
+ ///
+ /// The `payment_paths` parameter is useful for maintaining the payment recipient's privacy. It
+ /// must contain one or more elements ordered from most-preferred to least-preferred, if there's
+ /// a preference. Note, however, that any privacy is lost if a public node id is used for
+ /// `signing_pubkey`.
+ ///
+ /// Errors if the request contains unknown required features.
+ ///
+ /// [`Invoice`]: crate::offers::invoice::Invoice
+ /// [`Invoice::created_at`]: crate::offers::invoice::Invoice::created_at
+ pub fn respond_with(
+ &self, payment_paths: Vec<(BlindedPath, BlindedPayInfo)>, payment_hash: PaymentHash,
+ signing_pubkey: PublicKey,
+ #[cfg(any(test, not(feature = "std")))]
+ created_at: Duration
+ ) -> Result<InvoiceBuilder, SemanticError> {
+ if self.features().requires_unknown_bits() {
+ return Err(SemanticError::UnknownRequiredFeatures);
+ }
+
+ #[cfg(all(not(test), feature = "std"))]
+ let created_at = std::time::SystemTime::now()
+ .duration_since(std::time::SystemTime::UNIX_EPOCH)
+ .expect("SystemTime::now() should come after SystemTime::UNIX_EPOCH");
+
+ InvoiceBuilder::for_refund(self, payment_paths, created_at, payment_hash, signing_pubkey)
+ }
+
#[cfg(test)]
fn as_tlv_stream(&self) -> RefundTlvStreamRef {
self.contents.as_tlv_stream()
}
impl RefundContents {
- fn chain(&self) -> ChainHash {
+ #[cfg(feature = "std")]
+ pub(super) fn is_expired(&self) -> bool {
+ match self.absolute_expiry {
+ Some(seconds_from_epoch) => match SystemTime::UNIX_EPOCH.elapsed() {
+ Ok(elapsed) => elapsed > seconds_from_epoch,
+ Err(_) => false,
+ },
+ None => false,
+ }
+ }
+
+ pub(super) fn chain(&self) -> ChainHash {
self.chain.unwrap_or_else(|| self.implied_chain())
}
let offer = OfferTlvStreamRef {
chains: None,
- metadata: self.metadata.as_ref(),
+ metadata: None,
currency: None,
amount: None,
description: Some(&self.description),
chain: self.chain.as_ref(),
amount: Some(self.amount_msats),
features,
- quantity: None,
+ quantity: self.quantity,
payer_id: Some(&self.payer_id),
payer_note: self.payer_note.as_ref(),
};
Some(metadata) => PayerContents(metadata),
};
+ if metadata.is_some() {
+ return Err(SemanticError::UnexpectedMetadata);
+ }
+
if chains.is_some() {
return Err(SemanticError::UnexpectedChain);
}
let features = features.unwrap_or_else(InvoiceRequestFeatures::empty);
- // TODO: Check why this isn't in the spec.
- if quantity.is_some() {
- return Err(SemanticError::UnexpectedQuantity);
- }
-
let payer_id = match payer_id {
None => return Err(SemanticError::MissingPayerId),
Some(payer_id) => payer_id,
};
- // TODO: Should metadata be included?
Ok(RefundContents {
- payer, metadata, description, absolute_expiry, issuer, paths, chain, amount_msats,
- features, payer_id, payer_note,
+ payer, description, absolute_expiry, issuer, paths, chain, amount_msats, features,
+ quantity, payer_id, payer_note,
})
}
}
#[cfg(test)]
mod tests {
- use super::{Refund, RefundBuilder};
+ use super::{Refund, RefundBuilder, RefundTlvStreamRef};
use bitcoin::blockdata::constants::ChainHash;
use bitcoin::network::constants::Network;
use bitcoin::secp256k1::{KeyPair, PublicKey, Secp256k1, SecretKey};
use core::convert::TryFrom;
use core::time::Duration;
- use crate::ln::features::InvoiceRequestFeatures;
- use crate::ln::msgs::MAX_VALUE_MSAT;
+ use crate::ln::features::{InvoiceRequestFeatures, OfferFeatures};
+ use crate::ln::msgs::{DecodeError, MAX_VALUE_MSAT};
use crate::offers::invoice_request::InvoiceRequestTlvStreamRef;
use crate::offers::offer::OfferTlvStreamRef;
- use crate::offers::parse::SemanticError;
+ use crate::offers::parse::{ParseError, SemanticError};
use crate::offers::payer::PayerTlvStreamRef;
use crate::onion_message::{BlindedHop, BlindedPath};
- use crate::util::ser::Writeable;
+ use crate::util::ser::{BigSize, Writeable};
use crate::util::string::PrintableString;
fn payer_pubkey() -> PublicKey {
SecretKey::from_slice(&[byte; 32]).unwrap()
}
+ trait ToBytes {
+ fn to_bytes(&self) -> Vec<u8>;
+ }
+
+ impl<'a> ToBytes for RefundTlvStreamRef<'a> {
+ fn to_bytes(&self) -> Vec<u8> {
+ let mut buffer = Vec::new();
+ self.write(&mut buffer).unwrap();
+ buffer
+ }
+ }
+
#[test]
fn builds_refund_with_defaults() {
let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
assert_eq!(tlv_stream.chain, Some(&testnet));
}
+ #[test]
+ fn builds_refund_with_quantity() {
+ let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
+ .quantity(10)
+ .build().unwrap();
+ let (_, _, tlv_stream) = refund.as_tlv_stream();
+ assert_eq!(refund.quantity(), Some(10));
+ assert_eq!(tlv_stream.quantity, Some(10));
+
+ let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
+ .quantity(10)
+ .quantity(1)
+ .build().unwrap();
+ let (_, _, tlv_stream) = refund.as_tlv_stream();
+ assert_eq!(refund.quantity(), Some(1));
+ assert_eq!(tlv_stream.quantity, Some(1));
+ }
+
#[test]
fn builds_refund_with_payer_note() {
let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
assert_eq!(refund.payer_note(), Some(PrintableString("baz")));
assert_eq!(tlv_stream.payer_note, Some(&String::from("baz")));
}
+
+ #[test]
+ fn parses_refund_with_metadata() {
+ let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
+ .build().unwrap();
+ if let Err(e) = refund.to_string().parse::<Refund>() {
+ panic!("error parsing refund: {:?}", e);
+ }
+
+ let mut tlv_stream = refund.as_tlv_stream();
+ tlv_stream.0.metadata = None;
+
+ match Refund::try_from(tlv_stream.to_bytes()) {
+ Ok(_) => panic!("expected error"),
+ Err(e) => {
+ assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPayerMetadata));
+ },
+ }
+ }
+
+ #[test]
+ fn parses_refund_with_description() {
+ let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
+ .build().unwrap();
+ if let Err(e) = refund.to_string().parse::<Refund>() {
+ panic!("error parsing refund: {:?}", e);
+ }
+
+ let mut tlv_stream = refund.as_tlv_stream();
+ tlv_stream.1.description = None;
+
+ match Refund::try_from(tlv_stream.to_bytes()) {
+ Ok(_) => panic!("expected error"),
+ Err(e) => {
+ assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingDescription));
+ },
+ }
+ }
+
+ #[test]
+ fn parses_refund_with_amount() {
+ let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
+ .build().unwrap();
+ if let Err(e) = refund.to_string().parse::<Refund>() {
+ panic!("error parsing refund: {:?}", e);
+ }
+
+ let mut tlv_stream = refund.as_tlv_stream();
+ tlv_stream.2.amount = None;
+
+ match Refund::try_from(tlv_stream.to_bytes()) {
+ Ok(_) => panic!("expected error"),
+ Err(e) => {
+ assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingAmount));
+ },
+ }
+
+ let mut tlv_stream = refund.as_tlv_stream();
+ tlv_stream.2.amount = Some(MAX_VALUE_MSAT + 1);
+
+ match Refund::try_from(tlv_stream.to_bytes()) {
+ Ok(_) => panic!("expected error"),
+ Err(e) => {
+ assert_eq!(e, ParseError::InvalidSemantics(SemanticError::InvalidAmount));
+ },
+ }
+ }
+
+ #[test]
+ fn parses_refund_with_payer_id() {
+ let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
+ .build().unwrap();
+ if let Err(e) = refund.to_string().parse::<Refund>() {
+ panic!("error parsing refund: {:?}", e);
+ }
+
+ let mut tlv_stream = refund.as_tlv_stream();
+ tlv_stream.2.payer_id = None;
+
+ match Refund::try_from(tlv_stream.to_bytes()) {
+ Ok(_) => panic!("expected error"),
+ Err(e) => {
+ assert_eq!(e, ParseError::InvalidSemantics(SemanticError::MissingPayerId));
+ },
+ }
+ }
+
+ #[test]
+ fn parses_refund_with_optional_fields() {
+ let past_expiry = Duration::from_secs(0);
+ let paths = vec![
+ BlindedPath {
+ introduction_node_id: pubkey(40),
+ blinding_point: pubkey(41),
+ blinded_hops: vec![
+ BlindedHop { blinded_node_id: pubkey(43), encrypted_payload: vec![0; 43] },
+ BlindedHop { blinded_node_id: pubkey(44), encrypted_payload: vec![0; 44] },
+ ],
+ },
+ BlindedPath {
+ introduction_node_id: pubkey(40),
+ blinding_point: pubkey(41),
+ blinded_hops: vec![
+ BlindedHop { blinded_node_id: pubkey(45), encrypted_payload: vec![0; 45] },
+ BlindedHop { blinded_node_id: pubkey(46), encrypted_payload: vec![0; 46] },
+ ],
+ },
+ ];
+
+ let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
+ .absolute_expiry(past_expiry)
+ .issuer("bar".into())
+ .path(paths[0].clone())
+ .path(paths[1].clone())
+ .chain(Network::Testnet)
+ .features_unchecked(InvoiceRequestFeatures::unknown())
+ .quantity(10)
+ .payer_note("baz".into())
+ .build()
+ .unwrap();
+ match refund.to_string().parse::<Refund>() {
+ Ok(refund) => {
+ assert_eq!(refund.absolute_expiry(), Some(past_expiry));
+ #[cfg(feature = "std")]
+ assert!(refund.is_expired());
+ assert_eq!(refund.paths(), &paths[..]);
+ assert_eq!(refund.issuer(), Some(PrintableString("bar")));
+ assert_eq!(refund.chain(), ChainHash::using_genesis_block(Network::Testnet));
+ assert_eq!(refund.features(), &InvoiceRequestFeatures::unknown());
+ assert_eq!(refund.quantity(), Some(10));
+ assert_eq!(refund.payer_note(), Some(PrintableString("baz")));
+ },
+ Err(e) => panic!("error parsing refund: {:?}", e),
+ }
+ }
+
+ #[test]
+ fn fails_parsing_refund_with_unexpected_fields() {
+ let refund = RefundBuilder::new("foo".into(), vec![1; 32], payer_pubkey(), 1000).unwrap()
+ .build().unwrap();
+ if let Err(e) = refund.to_string().parse::<Refund>() {
+ panic!("error parsing refund: {:?}", e);
+ }
+
+ let metadata = vec![42; 32];
+ let mut tlv_stream = refund.as_tlv_stream();
+ tlv_stream.1.metadata = Some(&metadata);
+
+ match Refund::try_from(tlv_stream.to_bytes()) {
+ Ok(_) => panic!("expected error"),
+ Err(e) => {
+ assert_eq!(e, ParseError::InvalidSemantics(SemanticError::UnexpectedMetadata));
+ },
+ }
+
+ let chains = vec![ChainHash::using_genesis_block(Network::Testnet)];
+ let mut tlv_stream = refund.as_tlv_stream();
+ tlv_stream.1.chains = Some(&chains);
+
+ match Refund::try_from(tlv_stream.to_bytes()) {
+ Ok(_) => panic!("expected error"),
+ Err(e) => {
+ assert_eq!(e, ParseError::InvalidSemantics(SemanticError::UnexpectedChain));
+ },
+ }
+
+ let mut tlv_stream = refund.as_tlv_stream();
+ tlv_stream.1.currency = Some(&b"USD");
+ tlv_stream.1.amount = Some(1000);
+
+ match Refund::try_from(tlv_stream.to_bytes()) {
+ Ok(_) => panic!("expected error"),
+ Err(e) => {
+ assert_eq!(e, ParseError::InvalidSemantics(SemanticError::UnexpectedAmount));
+ },
+ }
+
+ let features = OfferFeatures::unknown();
+ let mut tlv_stream = refund.as_tlv_stream();
+ tlv_stream.1.features = Some(&features);
+
+ match Refund::try_from(tlv_stream.to_bytes()) {
+ Ok(_) => panic!("expected error"),
+ Err(e) => {
+ assert_eq!(e, ParseError::InvalidSemantics(SemanticError::UnexpectedFeatures));
+ },
+ }
+
+ let mut tlv_stream = refund.as_tlv_stream();
+ tlv_stream.1.quantity_max = Some(10);
+
+ match Refund::try_from(tlv_stream.to_bytes()) {
+ Ok(_) => panic!("expected error"),
+ Err(e) => {
+ assert_eq!(e, ParseError::InvalidSemantics(SemanticError::UnexpectedQuantity));
+ },
+ }
+
+ let node_id = payer_pubkey();
+ let mut tlv_stream = refund.as_tlv_stream();
+ tlv_stream.1.node_id = Some(&node_id);
+
+ match Refund::try_from(tlv_stream.to_bytes()) {
+ Ok(_) => panic!("expected error"),
+ Err(e) => {
+ assert_eq!(e, ParseError::InvalidSemantics(SemanticError::UnexpectedSigningPubkey));
+ },
+ }
+ }
+
+ #[test]
+ fn fails_parsing_refund_with_extra_tlv_records() {
+ let secp_ctx = Secp256k1::new();
+ let keys = KeyPair::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
+ let refund = RefundBuilder::new("foo".into(), vec![1; 32], keys.public_key(), 1000).unwrap()
+ .build().unwrap();
+
+ let mut encoded_refund = Vec::new();
+ refund.write(&mut encoded_refund).unwrap();
+ BigSize(1002).write(&mut encoded_refund).unwrap();
+ BigSize(32).write(&mut encoded_refund).unwrap();
+ [42u8; 32].write(&mut encoded_refund).unwrap();
+
+ match Refund::try_from(encoded_refund) {
+ Ok(_) => panic!("expected error"),
+ Err(e) => assert_eq!(e, ParseError::Decode(DecodeError::InvalidValue)),
+ }
+ }
}
projects / rust-lightning / blobdiff