pub(super) fn blinded_hops<T: secp256k1::Signing + secp256k1::Verification>(
secp_ctx: &Secp256k1<T>, unblinded_path: &[PublicKey], session_priv: &SecretKey
) -> Result<Vec<BlindedHop>, secp256k1::Error> {
- let mut blinded_hops = Vec::with_capacity(unblinded_path.len());
+ let blinded_tlvs = unblinded_path.iter()
+ .skip(1) // The first node's TLVs contains the next node's pubkey
+ .map(|pk| {
+ ControlTlvs::Forward(ForwardTlvs { next_node_id: *pk, next_blinding_override: None })
+ })
+ .chain(core::iter::once(ControlTlvs::Receive(ReceiveTlvs { path_id: None })));
- let mut prev_ss_and_blinded_node_id = None;
- utils::construct_keys_callback(secp_ctx, unblinded_path.iter(), None, session_priv,
- |blinded_node_id, _, _, encrypted_payload_ss, unblinded_pk, _| {
- if let Some((prev_ss, prev_blinded_node_id)) = prev_ss_and_blinded_node_id {
- if let Some(pk) = unblinded_pk {
- let payload = ForwardTlvs {
- next_node_id: pk,
- next_blinding_override: None,
- };
- blinded_hops.push(BlindedHop {
- blinded_node_id: prev_blinded_node_id,
- encrypted_payload: utils::encrypt_payload(payload, prev_ss),
- });
- } else { debug_assert!(false); }
- }
- prev_ss_and_blinded_node_id = Some((encrypted_payload_ss, blinded_node_id));
- })?;
-
- if let Some((final_ss, final_blinded_node_id)) = prev_ss_and_blinded_node_id {
- let final_payload = ReceiveTlvs { path_id: None };
- blinded_hops.push(BlindedHop {
- blinded_node_id: final_blinded_node_id,
- encrypted_payload: utils::encrypt_payload(final_payload, final_ss),
- });
- } else { debug_assert!(false) }
-
- Ok(blinded_hops)
+ utils::construct_blinded_hops(secp_ctx, unblinded_path.iter(), blinded_tlvs, session_priv)
}
// Advance the blinded onion message path by one hop, so make the second hop into the new