Merge pull request #1503 from valentinewallace/2022-05-onion-msgs

[rust-lightning] / lightning / src / ln / msgs.rs

diff --git a/lightning/src/ln/msgs.rs b/lightning/src/ln/msgs.rs
index c2925d7354de4142c109ee79bf7b8c33fb0819ba..05a336c18eff5634e0fee7f2cec8b86a66e02a89 100644 (file)
--- a/lightning/src/ln/msgs.rs
+++ b/lightning/src/ln/msgs.rs
@@ -31,6 +31,8 @@ use bitcoin::blockdata::script::Script;
 use bitcoin::hash_types::{Txid, BlockHash};
 
 use ln::features::{ChannelFeatures, ChannelTypeFeatures, InitFeatures, NodeFeatures};
+use ln::onion_utils;
+use onion_message;
 
 use prelude::*;
 use core::fmt;
@@ -40,7 +42,7 @@ use io_extras::read_to_end;
 
 use util::events::MessageSendEventsProvider;
 use util::logger;
-use util::ser::{Readable, Writeable, Writer, FixedLengthReader, HighZeroBytesDroppedVarInt, Hostname};
+use util::ser::{LengthReadable, Readable, ReadableArgs, Writeable, Writer, FixedLengthReader, HighZeroBytesDroppedVarInt, Hostname};
 
 use ln::{PaymentPreimage, PaymentHash, PaymentSecret};
 
@@ -304,6 +306,14 @@ pub struct UpdateAddHTLC {
        pub(crate) onion_routing_packet: OnionPacket,
 }
 
+ /// An onion message to be sent or received from a peer
+#[derive(Clone, Debug, PartialEq)]
+pub struct OnionMessage {
+       /// Used in decrypting the onion packet's payload.
+       pub blinding_point: PublicKey,
+       pub(crate) onion_routing_packet: onion_message::Packet,
+}
+
 /// An update_fulfill_htlc message to be sent or received from a peer
 #[derive(Clone, Debug, PartialEq)]
 pub struct UpdateFulfillHTLC {
@@ -993,6 +1003,18 @@ pub(crate) struct OnionPacket {
        pub(crate) hmac: [u8; 32],
 }
 
+impl onion_utils::Packet for OnionPacket {
+       type Data = onion_utils::FixedSizeOnionPacket;
+       fn new(pubkey: PublicKey, hop_data: onion_utils::FixedSizeOnionPacket, hmac: [u8; 32]) -> Self {
+               Self {
+                       version: 0,
+                       public_key: Ok(pubkey),
+                       hop_data: hop_data.0,
+                       hmac,
+               }
+       }
+}
+
 impl PartialEq for OnionPacket {
        fn eq(&self, other: &OnionPacket) -> bool {
                for (i, j) in self.hop_data.iter().zip(other.hop_data.iter()) {
@@ -1327,6 +1349,29 @@ impl_writeable_msg!(UpdateAddHTLC, {
        onion_routing_packet
 }, {});
 
+impl Readable for OnionMessage {
+       fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+               let blinding_point: PublicKey = Readable::read(r)?;
+               let len: u16 = Readable::read(r)?;
+               let mut packet_reader = FixedLengthReader::new(r, len as u64);
+               let onion_routing_packet: onion_message::Packet = <onion_message::Packet as LengthReadable>::read(&mut packet_reader)?;
+               Ok(Self {
+                       blinding_point,
+                       onion_routing_packet,
+               })
+       }
+}
+
+impl Writeable for OnionMessage {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+               self.blinding_point.write(w)?;
+               let onion_packet_len = self.onion_routing_packet.serialized_length();
+               (onion_packet_len as u16).write(w)?;
+               self.onion_routing_packet.write(w)?;
+               Ok(())
+       }
+}
+
 impl Writeable for FinalOnionHopData {
        fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
                self.payment_secret.0.write(w)?;
@@ -1372,6 +1417,14 @@ impl Writeable for OnionHopData {
        }
 }
 
+// ReadableArgs because we need onion_utils::decode_next_hop to accommodate payment packets and
+// onion message packets.
+impl ReadableArgs<()> for OnionHopData {
+       fn read<R: Read>(r: &mut R, _arg: ()) -> Result<Self, DecodeError> {
+               <Self as Readable>::read(r)
+       }
+}
+
 impl Readable for OnionHopData {
        fn read<R: Read>(mut r: &mut R) -> Result<Self, DecodeError> {
                use bitcoin::consensus::encode::{Decodable, Error, VarInt};