PF_RT_OS_FINGERPRINT
snl_add_msg_attr_u32(nw, PF_RT_OS_FINGERPRINT, r->os_fingerprint);
{ .type = PF_RT_OS_FINGERPRINT, .off = _OUT(r.os_fingerprint), .cb = snl_attr_get_uint32 },
{ .type = PF_RT_OS_FINGERPRINT, .off = _OUT(os_fingerprint), .cb = nlattr_get_uint32 },
nlattr_add_u32(nw, PF_RT_OS_FINGERPRINT, rule->os_fingerprint);