Pass multiple subcredentials all the way down to hs_ntor.

This approach saves us a pair of curve25519 operations for every
subcredential but the first.  It is not yet constant-time.

I've noted a few places where IMO we should refactor the code so
that the complete list of subcredentials is passed in earlier.

1 files changed, 4 insertions, 1 deletions

diff --git a/src/feature/hs/hs_circuit.c b/src/feature/hs/hs_circuit.c
index fb3694b2d4..48a92962f4 100644
--- a/src/feature/hs/hs_circuit.c
+++ b/src/feature/hs/hs_circuit.c
@@ -983,7 +983,10 @@ hs_circ_handle_introduce2(const hs_service_t *service,
    * parsed, decrypted and key material computed correctly. */
   data.auth_pk = &ip->auth_key_kp.pubkey;
   data.enc_kp = &ip->enc_key_kp;
-  data.subcredential = subcredential;
+  // XXXX We should replace these elements with something precomputed for
+  // XXXX the onionbalance case.
+  data.n_subcredentials = 1;
+  data.subcredentials = subcredential;
   data.payload = payload;
   data.payload_len = payload_len;
   data.link_specifiers = smartlist_new();