[tor-bugs] #33069 [Core Tor/Tor]: Init sk if loaded from service blob to be on the curve

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#33069: Init sk if loaded from service blob to be on the curve
-------------------------+------------------------------
 Reporter:  saibato      |          Owner:  (none)
     Type:  enhancement  |         Status:  new
 Priority:  Medium       |      Component:  Core Tor/Tor
  Version:               |       Severity:  Trivial
 Keywords:               |  Actual Points:
Parent ID:               |         Points:
 Reviewer:               |        Sponsor:
-------------------------+------------------------------
 diff --git a/src/feature/hs/hs_service.c b/src/feature/hs/hs_service.c
 index 81b37eab4..300fedc4f 100644
 --- a/src/feature/hs/hs_service.c
 +++ b/src/feature/hs/hs_service.c
 @@ -3548,6 +3548,12 @@ hs_service_add_ephemeral(ed25519_secret_key_t *sk,
 smartlist_t *ports,

    /* Handle the keys. */
    memcpy(&service->keys.identity_sk, sk,
 sizeof(service->keys.identity_sk));
 +
 +  /* QAD make sure the scalar is on the curve since ed25519_donna_pubkey
 will probably return 0 */
 +  service->keys.identity_sk[0] &= 248;
 +  service->keys.identity_sk[31] &= 127;
 +  service->keys.identity_sk[31] |= 64;
 +
    if (ed25519_public_key_generate(&service->keys.identity_pk,
                                    &service->keys.identity_sk) < 0) {
      log_warn(LD_CONFIG, "Unable to generate ed25519 public key"

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/33069>
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