From 3e9678d496c425e782ee460ac92ff272be52c036 Mon Sep 17 00:00:00 2001 From: Andre Puschmann Date: Fri, 13 Mar 2020 14:46:32 +0100 Subject: [PATCH] srsepc: send detach accept when receiving detach request for non-switchoff --- srsepc/src/mme/nas.cc | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/srsepc/src/mme/nas.cc b/srsepc/src/mme/nas.cc index 0f7e6b001..e7fe1f304 100644 --- a/srsepc/src/mme/nas.cc +++ b/srsepc/src/mme/nas.cc @@ -765,6 +765,31 @@ bool nas::handle_detach_request(uint32_t m_tmsi, ecm_ctx_t* ecm_ctx = &nas_ctx->m_ecm_ctx; sec_ctx_t* sec_ctx = &nas_ctx->m_sec_ctx; + // TS 24.301, Sec 5.5.2.2.1, UE initiated detach request + if (detach_req.detach_type.switch_off == 0) { + // UE expects detach accept + srsran::unique_byte_buffer_t nas_tx = srsran::make_byte_buffer(); + if (nas_tx == nullptr) { + nas_logger.error("Couldn't allocate PDU in %s().", __FUNCTION__); + return false; + } + + LIBLTE_MME_DETACH_ACCEPT_MSG_STRUCT detach_accept = {}; + err = liblte_mme_pack_detach_accept_msg(&detach_accept, + LIBLTE_MME_SECURITY_HDR_TYPE_PLAIN_NAS, + sec_ctx->dl_nas_count, + (LIBLTE_BYTE_MSG_STRUCT*)nas_tx.get()); + if (err != LIBLTE_SUCCESS) { + nas_logger.error("Error packing Detach Accept\n"); + } + + nas_logger.info("Sending detach accept.\n"); + sec_ctx->dl_nas_count++; + s1ap->send_downlink_nas_transport(enb_ue_s1ap_id, s1ap->get_next_mme_ue_s1ap_id(), nas_tx.get(), *enb_sri); + } else { + nas_logger.info("UE is switched off\n"); + } + gtpc->send_delete_session_request(emm_ctx->imsi); emm_ctx->state = EMM_STATE_DEREGISTERED; sec_ctx->ul_nas_count++;