1 // This file is Copyright its original authors, visible in version control
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
10 //! Message handling for BOLT 12 Offers.
12 use core::convert::TryFrom;
13 use crate::io::{self, Read};
14 use crate::ln::msgs::DecodeError;
15 use crate::offers::invoice_error::InvoiceError;
16 use crate::offers::invoice_request::InvoiceRequest;
17 use crate::offers::invoice::Bolt12Invoice;
18 use crate::offers::parse::Bolt12ParseError;
19 use crate::onion_message::OnionMessageContents;
20 use crate::onion_message::messenger::PendingOnionMessage;
21 use crate::util::logger::Logger;
22 use crate::util::ser::{Readable, ReadableArgs, Writeable, Writer};
24 use crate::prelude::*;
26 // TLV record types for the `onionmsg_tlv` TLV stream as defined in BOLT 4.
27 const INVOICE_REQUEST_TLV_TYPE: u64 = 64;
28 const INVOICE_TLV_TYPE: u64 = 66;
29 const INVOICE_ERROR_TLV_TYPE: u64 = 68;
31 /// A handler for an [`OnionMessage`] containing a BOLT 12 Offers message as its payload.
33 /// [`OnionMessage`]: crate::ln::msgs::OnionMessage
34 pub trait OffersMessageHandler {
35 /// Handles the given message by either responding with an [`Bolt12Invoice`], sending a payment,
36 /// or replying with an error.
38 /// The returned [`OffersMessage`], if any, is enqueued to be sent by [`OnionMessenger`].
40 /// [`OnionMessenger`]: crate::onion_message::OnionMessenger
41 fn handle_message(&self, message: OffersMessage) -> Option<OffersMessage>;
43 /// Releases any [`OffersMessage`]s that need to be sent.
45 /// Typically, this is used for messages initiating a payment flow rather than in response to
46 /// another message. The latter should use the return value of [`Self::handle_message`].
47 #[cfg(not(c_bindings))]
48 fn release_pending_messages(&self) -> Vec<PendingOnionMessage<OffersMessage>> { vec![] }
50 /// Releases any [`OffersMessage`]s that need to be sent.
52 /// Typically, this is used for messages initiating a payment flow rather than in response to
53 /// another message. The latter should use the return value of [`Self::handle_message`].
55 fn release_pending_messages(&self) -> Vec<(OffersMessage, crate::onion_message::Destination, Option<crate::blinded_path::BlindedPath>)> { vec![] }
58 /// Possible BOLT 12 Offers messages sent and received via an [`OnionMessage`].
60 /// [`OnionMessage`]: crate::ln::msgs::OnionMessage
61 #[derive(Clone, Debug)]
62 pub enum OffersMessage {
63 /// A request for a [`Bolt12Invoice`] for a particular [`Offer`].
65 /// [`Offer`]: crate::offers::offer::Offer
66 InvoiceRequest(InvoiceRequest),
68 /// A [`Bolt12Invoice`] sent in response to an [`InvoiceRequest`] or a [`Refund`].
70 /// [`Refund`]: crate::offers::refund::Refund
71 Invoice(Bolt12Invoice),
73 /// An error from handling an [`OffersMessage`].
74 InvoiceError(InvoiceError),
78 /// Returns whether `tlv_type` corresponds to a TLV record for Offers.
79 pub fn is_known_type(tlv_type: u64) -> bool {
81 INVOICE_REQUEST_TLV_TYPE | INVOICE_TLV_TYPE | INVOICE_ERROR_TLV_TYPE => true,
86 fn parse(tlv_type: u64, bytes: Vec<u8>) -> Result<Self, Bolt12ParseError> {
88 INVOICE_REQUEST_TLV_TYPE => Ok(Self::InvoiceRequest(InvoiceRequest::try_from(bytes)?)),
89 INVOICE_TLV_TYPE => Ok(Self::Invoice(Bolt12Invoice::try_from(bytes)?)),
90 _ => Err(Bolt12ParseError::Decode(DecodeError::InvalidValue)),
95 impl OnionMessageContents for OffersMessage {
96 fn tlv_type(&self) -> u64 {
98 OffersMessage::InvoiceRequest(_) => INVOICE_REQUEST_TLV_TYPE,
99 OffersMessage::Invoice(_) => INVOICE_TLV_TYPE,
100 OffersMessage::InvoiceError(_) => INVOICE_ERROR_TLV_TYPE,
105 impl Writeable for OffersMessage {
106 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
108 OffersMessage::InvoiceRequest(message) => message.write(w),
109 OffersMessage::Invoice(message) => message.write(w),
110 OffersMessage::InvoiceError(message) => message.write(w),
115 impl<L: Logger + ?Sized> ReadableArgs<(u64, &L)> for OffersMessage {
116 fn read<R: Read>(r: &mut R, read_args: (u64, &L)) -> Result<Self, DecodeError> {
117 let (tlv_type, logger) = read_args;
118 if tlv_type == INVOICE_ERROR_TLV_TYPE {
119 return Ok(Self::InvoiceError(InvoiceError::read(r)?));
122 let mut bytes = Vec::new();
123 r.read_to_end(&mut bytes).unwrap();
125 match Self::parse(tlv_type, bytes) {
126 Ok(message) => Ok(message),
127 Err(Bolt12ParseError::Decode(e)) => Err(e),
128 Err(Bolt12ParseError::InvalidSemantics(e)) => {
129 log_trace!(logger, "Invalid semantics for TLV type {}: {:?}", tlv_type, e);
130 Err(DecodeError::InvalidValue)
132 Err(Bolt12ParseError::InvalidSignature(e)) => {
133 log_trace!(logger, "Invalid signature for TLV type {}: {:?}", tlv_type, e);
134 Err(DecodeError::InvalidValue)
136 Err(_) => Err(DecodeError::InvalidValue),