AUTHTAG_LEN
if (aesgcm_expandkey(ctx, key, keylen, AUTHTAG_LEN)) {
tsc_resp = kzalloc(sizeof(*tsc_resp) + AUTHTAG_LEN, GFP_KERNEL);
req.resp_sz = sizeof(*tsc_resp) + AUTHTAG_LEN;
memzero_explicit(tsc_resp, sizeof(*tsc_resp) + AUTHTAG_LEN);