Support sending and receiving reply paths

[rust-lightning] / lightning / src / onion_message / messenger.rs

diff --git a/lightning/src/onion_message/messenger.rs b/lightning/src/onion_message/messenger.rs
index c264cbc387f2609a1b8a56c204b4102cdbf433e1..a5438afbb8ea0eda20e619dcf7563cff884b706f 100644 (file)
--- a/lightning/src/onion_message/messenger.rs
+++ b/lightning/src/onion_message/messenger.rs
@@ -142,7 +142,7 @@ impl<Signer: Sign, K: Deref, L: Deref> OnionMessenger<Signer, K, L>
 
        /// Send an empty onion message to `destination`, routing it through `intermediate_nodes`.
        /// See [`OnionMessenger`] for example usage.
-       pub fn send_onion_message(&self, intermediate_nodes: &[PublicKey], destination: Destination) -> Result<(), SendError> {
+       pub fn send_onion_message(&self, intermediate_nodes: &[PublicKey], destination: Destination, reply_path: Option<BlindedRoute>) -> Result<(), SendError> {
                if let Destination::BlindedRoute(BlindedRoute { ref blinded_hops, .. }) = destination {
                        if blinded_hops.len() < 2 {
                                return Err(SendError::TooFewBlindedHops);
@@ -160,7 +160,7 @@ impl<Signer: Sign, K: Deref, L: Deref> OnionMessenger<Signer, K, L>
                        }
                };
                let (packet_payloads, packet_keys) = packet_payloads_and_keys(
-                       &self.secp_ctx, intermediate_nodes, destination, &blinding_secret)
+                       &self.secp_ctx, intermediate_nodes, destination, reply_path, &blinding_secret)
                        .map_err(|e| SendError::Secp256k1(e))?;
 
                let prng_seed = self.keys_manager.get_secure_random_bytes();
@@ -209,9 +209,11 @@ impl<Signer: Sign, K: Deref, L: Deref> OnionMessenger<Signer, K, L>
                        msg.onion_routing_packet.hmac, control_tlvs_ss)
                {
                        Ok((Payload::Receive {
-                               control_tlvs: ReceiveControlTlvs::Unblinded(ReceiveTlvs { path_id })
+                               control_tlvs: ReceiveControlTlvs::Unblinded(ReceiveTlvs { path_id }), reply_path,
                        }, None)) => {
-                               log_info!(self.logger, "Received an onion message with path_id: {:02x?}", path_id);
+                               log_info!(self.logger,
+                                       "Received an onion message with path_id: {:02x?} and {}reply_path",
+                                               path_id, if reply_path.is_some() { "" } else { "no " });
                        },
                        Ok((Payload::Forward(ForwardControlTlvs::Unblinded(ForwardTlvs {
                                next_node_id, next_blinding_override
@@ -299,7 +301,8 @@ pub type SimpleRefOnionMessenger<'a, 'b, L> = OnionMessenger<InMemorySigner, &'a
 /// Construct onion packet payloads and keys for sending an onion message along the given
 /// `unblinded_path` to the given `destination`.
 fn packet_payloads_and_keys<T: secp256k1::Signing + secp256k1::Verification>(
-       secp_ctx: &Secp256k1<T>, unblinded_path: &[PublicKey], destination: Destination, session_priv: &SecretKey
+       secp_ctx: &Secp256k1<T>, unblinded_path: &[PublicKey], destination: Destination, mut reply_path:
+       Option<BlindedRoute>, session_priv: &SecretKey
 ) -> Result<(Vec<(Payload, [u8; 32])>, Vec<onion_utils::OnionKeys>), secp256k1::Error> {
        let num_hops = unblinded_path.len() + destination.num_hops();
        let mut payloads = Vec::with_capacity(num_hops);
@@ -344,6 +347,7 @@ fn packet_payloads_and_keys<T: secp256k1::Signing + secp256k1::Verification>(
                } else if let Some(encrypted_payload) = enc_payload_opt {
                        payloads.push((Payload::Receive {
                                control_tlvs: ReceiveControlTlvs::Blinded(encrypted_payload),
+                               reply_path: reply_path.take(),
                        }, control_tlvs_ss));
                }
 
@@ -361,7 +365,8 @@ fn packet_payloads_and_keys<T: secp256k1::Signing + secp256k1::Verification>(
 
        if let Some(control_tlvs_ss) = prev_control_tlvs_ss {
                payloads.push((Payload::Receive {
-                       control_tlvs: ReceiveControlTlvs::Unblinded(ReceiveTlvs { path_id: None, })
+                       control_tlvs: ReceiveControlTlvs::Unblinded(ReceiveTlvs { path_id: None, }),
+                       reply_path: reply_path.take(),
                }, control_tlvs_ss));
        }