sm: Implement initial support for keyboxd.

* sm/gpgsm.h (MAX_FINGERPRINT_LEN): New.
* sm/keydb.c (struct keydb_local_s): Change definition of
search_result.
(keydb_get_cert): Implement keyboxd mode.
(keydb_get_flags): Temporary hack for keyboxd mode.  Needs to be
fixed.
(struct store_parm_s, store_inq_cb): New.
(keydb_insert_cert): Implement keyboxd mode.
(keydb_locate_writable): Make static.
(keydb_search_reset): Implement keyboxd mode.
(search_status_cb): New.
(keydb_search): Implement keyboxd mode. Replace return code -1 by
GPG_ERR_NOT_FOUND.
(keydb_set_cert_flags): Replace return code -1 by GPG_ERR_NOT_FOUND.
* sm/keylist.c (list_cert_colon): Adjust for replacement of -1 by
GPG_ERR_NOT_FOUND.
(list_internal_keys): Ditto.
* sm/sign.c (add_certificate_list): Ditto.
* sm/certchain.c (find_up_search_by_keyid): Ditto.
(find_up_external, find_up, find_up_dirmngr): Ditto.
(gpgsm_walk_cert_chain): Ditto.
(get_regtp_ca_info): Ditto.
* sm/certlist.c (gpgsm_add_to_certlist): Ditto.
(gpgsm_find_cert): Ditto.
* sm/delete.c (delete_one): Ditto.
* sm/export.c (gpgsm_export): Ditto.
(gpgsm_p12_export): Ditto.
* sm/import.c (gpgsm_import_files): Ditto.
--

Note that keyboxd is not yet able to handle the ephemeral flag.  This
needs fixing here and in keyboxd.  Delete et al. is also not yet
implemented.  A basic key listing works, though.

Signed-off-by: Werner Koch <wk@gnupg.org>

sm/sign.c

@@ -291,7 +291,7 @@ add_certificate_list (ctrl_t ctrl, ksba_cms_t cms, ksba_cert_t cert)
     }
   ksba_cert_release (cert);
 
-  return rc == -1? 0: rc;
+  return gpg_err_code (rc) == GPG_ERR_NOT_FOUND? 0 : rc;
 
  ksba_failure:
   ksba_cert_release (cert);