diff --git a/lightning/src/blinded_path/message.rs b/lightning/src/blinded_path/message.rs index 369a12243..bdbb4be45 100644 --- a/lightning/src/blinded_path/message.rs +++ b/lightning/src/blinded_path/message.rs @@ -106,6 +106,8 @@ pub(super) fn blinded_hops( // Advance the blinded onion message path by one hop, so make the second hop into the new // introduction node. +// +// Will only modify `path` when returning `Ok`. pub(crate) fn advance_path_by_one( path: &mut BlindedPath, node_signer: &NS, node_id_lookup: &NL, secp_ctx: &Secp256k1 ) -> Result<(), ()> @@ -116,8 +118,8 @@ where { let control_tlvs_ss = node_signer.ecdh(Recipient::Node, &path.blinding_point, None)?; let rho = onion_utils::gen_rho_from_shared_secret(&control_tlvs_ss.secret_bytes()); - let encrypted_control_tlvs = path.blinded_hops.remove(0).encrypted_payload; - let mut s = Cursor::new(&encrypted_control_tlvs); + let encrypted_control_tlvs = &path.blinded_hops.get(0).ok_or(())?.encrypted_payload; + let mut s = Cursor::new(encrypted_control_tlvs); let mut reader = FixedLengthReader::new(&mut s, encrypted_control_tlvs.len() as u64); match ChaChaPolyReadAdapter::read(&mut reader, rho) { Ok(ChaChaPolyReadAdapter { @@ -139,6 +141,7 @@ where }; mem::swap(&mut path.blinding_point, &mut new_blinding_point); path.introduction_node = IntroductionNode::NodeId(next_node_id); + path.blinded_hops.remove(0); Ok(()) }, _ => Err(())