_ Git - rust-lightning/blob - lightning/src/onion_message/offers.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 //! Message handling for BOLT 12 Offers.
  11
  12 use core::fmt;
  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::offers::static_invoice::StaticInvoice;
  20 use crate::onion_message::packet::OnionMessageContents;
  21 use crate::util::logger::Logger;
  22 use crate::util::ser::{Readable, ReadableArgs, Writeable, Writer};
  23 use crate::onion_message::messenger::{ResponseInstruction, Responder};
  24 #[cfg(not(c_bindings))]
  25 use crate::onion_message::messenger::PendingOnionMessage;
  26
  27 use crate::prelude::*;
  28
  29 // TLV record types for the `onionmsg_tlv` TLV stream as defined in BOLT 4.
  30 const INVOICE_REQUEST_TLV_TYPE: u64 = 64;
  31 const INVOICE_TLV_TYPE: u64 = 66;
  32 const INVOICE_ERROR_TLV_TYPE: u64 = 68;
  33 const STATIC_INVOICE_TLV_TYPE: u64 = 70;
  34
  35 /// A handler for an [`OnionMessage`] containing a BOLT 12 Offers message as its payload.
  36 ///
  37 /// [`OnionMessage`]: crate::ln::msgs::OnionMessage
  38 pub trait OffersMessageHandler {
  39         /// Handles the given message by either responding with an [`Bolt12Invoice`], sending a payment,
  40         /// or replying with an error.
  41         ///
  42         /// The returned [`OffersMessage`], if any, is enqueued to be sent by [`OnionMessenger`].
  43         ///
  44         /// [`OnionMessenger`]: crate::onion_message::messenger::OnionMessenger
  45         fn handle_message(&self, message: OffersMessage, responder: Option<Responder>) -> ResponseInstruction<OffersMessage>;
  46
  47         /// Releases any [`OffersMessage`]s that need to be sent.
  48         ///
  49         /// Typically, this is used for messages initiating a payment flow rather than in response to
  50         /// another message. The latter should use the return value of [`Self::handle_message`].
  51         #[cfg(not(c_bindings))]
  52         fn release_pending_messages(&self) -> Vec<PendingOnionMessage<OffersMessage>> { vec![] }
  53
  54         /// Releases any [`OffersMessage`]s that need to be sent.
  55         ///
  56         /// Typically, this is used for messages initiating a payment flow rather than in response to
  57         /// another message. The latter should use the return value of [`Self::handle_message`].
  58         #[cfg(c_bindings)]
  59         fn release_pending_messages(&self) -> Vec<(OffersMessage, crate::onion_message::messenger::Destination, Option<crate::blinded_path::BlindedPath>)> { vec![] }
  60 }
  61
  62 /// Possible BOLT 12 Offers messages sent and received via an [`OnionMessage`].
  63 ///
  64 /// [`OnionMessage`]: crate::ln::msgs::OnionMessage
  65 #[derive(Clone)]
  66 pub enum OffersMessage {
  67         /// A request for a [`Bolt12Invoice`] for a particular [`Offer`].
  68         ///
  69         /// [`Offer`]: crate::offers::offer::Offer
  70         InvoiceRequest(InvoiceRequest),
  71
  72         /// A [`Bolt12Invoice`] sent in response to an [`InvoiceRequest`] or a [`Refund`].
  73         ///
  74         /// [`Refund`]: crate::offers::refund::Refund
  75         Invoice(Bolt12Invoice),
  76
  77         /// A `StaticInvoice` sent in response to an [`InvoiceRequest`].
  78         StaticInvoice(StaticInvoice),
  79
  80         /// An error from handling an [`OffersMessage`].
  81         InvoiceError(InvoiceError),
  82 }
  83
  84 impl OffersMessage {
  85         /// Returns whether `tlv_type` corresponds to a TLV record for Offers.
  86         pub fn is_known_type(tlv_type: u64) -> bool {
  87                 match tlv_type {
  88                         INVOICE_REQUEST_TLV_TYPE
  89                         | INVOICE_TLV_TYPE
  90                         | STATIC_INVOICE_TLV_TYPE
  91                         | INVOICE_ERROR_TLV_TYPE => true,
  92                         _ => false,
  93                 }
  94         }
  95
  96         fn parse(tlv_type: u64, bytes: Vec<u8>) -> Result<Self, Bolt12ParseError> {
  97                 match tlv_type {
  98                         INVOICE_REQUEST_TLV_TYPE => Ok(Self::InvoiceRequest(InvoiceRequest::try_from(bytes)?)),
  99                         INVOICE_TLV_TYPE => Ok(Self::Invoice(Bolt12Invoice::try_from(bytes)?)),
 100                         STATIC_INVOICE_TLV_TYPE => Ok(Self::StaticInvoice(StaticInvoice::try_from(bytes)?)),
 101                         _ => Err(Bolt12ParseError::Decode(DecodeError::InvalidValue)),
 102                 }
 103         }
 104 }
 105
 106 impl fmt::Debug for OffersMessage {
 107         fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 108                 match self {
 109                         OffersMessage::InvoiceRequest(message) => {
 110                                 write!(f, "{:?}", message.as_tlv_stream())
 111                         }
 112                         OffersMessage::Invoice(message) => {
 113                                 write!(f, "{:?}", message.as_tlv_stream())
 114                         }
 115                         OffersMessage::StaticInvoice(message) => {
 116                                 write!(f, "{:?}", message)
 117                         }
 118                         OffersMessage::InvoiceError(message) => {
 119                                 write!(f, "{:?}", message)
 120                         }
 121                 }
 122         }
 123 }
 124
 125 impl OnionMessageContents for OffersMessage {
 126         fn tlv_type(&self) -> u64 {
 127                 match self {
 128                         OffersMessage::InvoiceRequest(_) => INVOICE_REQUEST_TLV_TYPE,
 129                         OffersMessage::Invoice(_) => INVOICE_TLV_TYPE,
 130                         OffersMessage::StaticInvoice(_) => STATIC_INVOICE_TLV_TYPE,
 131                         OffersMessage::InvoiceError(_) => INVOICE_ERROR_TLV_TYPE,
 132                 }
 133         }
 134         fn msg_type(&self) -> &'static str {
 135                 match &self {
 136                         OffersMessage::InvoiceRequest(_) => "Invoice Request",
 137                         OffersMessage::Invoice(_) => "Invoice",
 138                         OffersMessage::StaticInvoice(_) => "Static Invoice",
 139                         OffersMessage::InvoiceError(_) => "Invoice Error",
 140                 }
 141         }
 142 }
 143
 144 impl Writeable for OffersMessage {
 145         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 146                 match self {
 147                         OffersMessage::InvoiceRequest(message) => message.write(w),
 148                         OffersMessage::Invoice(message) => message.write(w),
 149                         OffersMessage::StaticInvoice(message) => message.write(w),
 150                         OffersMessage::InvoiceError(message) => message.write(w),
 151                 }
 152         }
 153 }
 154
 155 impl<L: Logger + ?Sized> ReadableArgs<(u64, &L)> for OffersMessage {
 156         fn read<R: Read>(r: &mut R, read_args: (u64, &L)) -> Result<Self, DecodeError> {
 157                 let (tlv_type, logger) = read_args;
 158                 if tlv_type == INVOICE_ERROR_TLV_TYPE {
 159                         return Ok(Self::InvoiceError(InvoiceError::read(r)?));
 160                 }
 161
 162                 let mut bytes = Vec::new();
 163                 r.read_to_end(&mut bytes).unwrap();
 164
 165                 match Self::parse(tlv_type, bytes) {
 166                         Ok(message) => Ok(message),
 167                         Err(Bolt12ParseError::Decode(e)) => Err(e),
 168                         Err(Bolt12ParseError::InvalidSemantics(e)) => {
 169                                 log_trace!(logger, "Invalid semantics for TLV type {}: {:?}", tlv_type, e);
 170                                 Err(DecodeError::InvalidValue)
 171                         },
 172                         Err(Bolt12ParseError::InvalidSignature(e)) => {
 173                                 log_trace!(logger, "Invalid signature for TLV type {}: {:?}", tlv_type, e);
 174                                 Err(DecodeError::InvalidValue)
 175                         },
 176                         Err(_) => Err(DecodeError::InvalidValue),
 177                 }
 178         }
 179 }