t4_copy_partial_hash
void t4_copy_partial_hash(int, union authctx *, void *);
t4_copy_partial_hash(axf->type, &auth_ctx, s->hmac.pads);
t4_copy_partial_hash(axf->type, &auth_ctx, dst);
t4_copy_partial_hash(axf->type, &auth_ctx, dst);