Quick and dirty hack to not send activate default eps bearer when a service request is received.

srsepc/hdr/mme/mme_gtpc.h

@@ -48,8 +48,8 @@ public:
   bool init(srslte::log_filter *mme_gtpc_log);
 
   uint32_t get_new_ctrl_teid();
-  void send_create_session_request(uint64_t imsi, uint32_t mme_s1ap_id);
-  void handle_create_session_response(srslte::gtpc_pdu *cs_resp_pdu);
+  void send_create_session_request(uint64_t imsi, uint32_t mme_s1ap_id, bool pack_attach);
+  void handle_create_session_response(srslte::gtpc_pdu *cs_resp_pdu, bool pack_attach);
   void send_modify_bearer_request(erab_ctx_t *bearer_ctx);
   void handle_modify_bearer_response(srslte::gtpc_pdu *mb_resp_pdu);
   void send_delete_session_request(ue_ecm_ctx_t *ue_ecm_ctx);

srsepc/hdr/mme/s1ap_ctx_mngmt_proc.h

@@ -48,7 +48,7 @@ public:
   void init(void);
 
   //bool send_initial_context_setup_request(uint32_t mme_ue_s1ap_id, struct srslte::gtpc_create_session_response *cs_resp, struct srslte::gtpc_f_teid_ie sgw_ctrl_fteid);
-  bool send_initial_context_setup_request(ue_emm_ctx_t *emm_ctx, ue_ecm_ctx_t *ecm_ctx, erab_ctx_t *erab_ctx);
+  bool send_initial_context_setup_request(ue_emm_ctx_t *emm_ctx, ue_ecm_ctx_t *ecm_ctx, erab_ctx_t *erab_ctx, bool pack_attach);
   bool handle_initial_context_setup_response(LIBLTE_S1AP_MESSAGE_INITIALCONTEXTSETUPRESPONSE_STRUCT *in_ctxt_resp);
   bool handle_ue_context_release_request(LIBLTE_S1AP_MESSAGE_UECONTEXTRELEASEREQUEST_STRUCT *ue_rel, struct sctp_sndrcvinfo *enb_sri, srslte::byte_buffer_t *reply_buffer, bool *reply_flag);
   bool send_ue_context_release_command(ue_ecm_ctx_t *ecm_ctx, srslte::byte_buffer_t *reply_buffer);

srsepc/hdr/spgw/spgw.h

@@ -73,7 +73,7 @@ public:
   void stop();
   void run_thread();
 
-  void handle_create_session_request(struct srslte::gtpc_create_session_request *cs_req, struct srslte::gtpc_pdu *cs_resp_pdu);
+  void handle_create_session_request(struct srslte::gtpc_create_session_request *cs_req, struct srslte::gtpc_pdu *cs_resp_pdu,bool pack_attach);
   void handle_modify_bearer_request(struct srslte::gtpc_pdu *mb_req_pdu, struct srslte::gtpc_pdu *mb_resp_pdu);
   void handle_delete_session_request(struct srslte::gtpc_pdu *del_req_pdu, struct srslte::gtpc_pdu *del_resp_pdu);
 

srsepc/src/mme/mme_gtpc.cc

@@ -88,7 +88,7 @@ mme_gtpc::get_new_ctrl_teid()
   return m_next_ctrl_teid++; //FIXME Use a Id pool?
 }
 void
-mme_gtpc::send_create_session_request(uint64_t imsi, uint32_t mme_ue_s1ap_id)
+mme_gtpc::send_create_session_request(uint64_t imsi, uint32_t mme_ue_s1ap_id, bool pack_attach)
 {
   m_mme_gtpc_log->info("Sending Create Session Request.\n");
   m_mme_gtpc_log->console("Sending Create Session Request.\n");
@@ -125,12 +125,12 @@ mme_gtpc::send_create_session_request(uint64_t imsi, uint32_t mme_ue_s1ap_id)
   //Save RX Control TEID
   m_teid_to_mme_s1ap_id.insert(std::pair<uint32_t,uint32_t>(cs_req->sender_f_teid.teid, mme_ue_s1ap_id));
 
-  m_spgw->handle_create_session_request(cs_req, &cs_resp_pdu);
+  m_spgw->handle_create_session_request(cs_req, &cs_resp_pdu, pack_attach);
  
 }
 
 void
-mme_gtpc::handle_create_session_response(srslte::gtpc_pdu *cs_resp_pdu)
+mme_gtpc::handle_create_session_response(srslte::gtpc_pdu *cs_resp_pdu, bool pack_attach)
 {
   struct srslte::gtpc_create_session_response *cs_resp = & cs_resp_pdu->choice.create_session_response;
   m_mme_gtpc_log->info("Received Create Session Response\n");
@@ -206,7 +206,7 @@ mme_gtpc::handle_create_session_response(srslte::gtpc_pdu *cs_resp_pdu)
   erab_ctx->sgw_ctrl_fteid = sgw_ctrl_fteid;
   erab_ctx->sgw_s1u_fteid = cs_resp->eps_bearer_context_created.s1_u_sgw_f_teid;
 
-  m_s1ap->m_s1ap_ctx_mngmt_proc->send_initial_context_setup_request(emm_ctx, ecm_ctx, erab_ctx);
+  m_s1ap->m_s1ap_ctx_mngmt_proc->send_initial_context_setup_request(emm_ctx, ecm_ctx, erab_ctx, pack_attach);
 }
 
 

srsepc/src/mme/s1ap_ctx_mngmt_proc.cc

@@ -79,8 +79,10 @@ s1ap_ctx_mngmt_proc::init(void)
 bool
 s1ap_ctx_mngmt_proc::send_initial_context_setup_request(ue_emm_ctx_t *emm_ctx,
                                                         ue_ecm_ctx_t *ecm_ctx,
-                                                        erab_ctx_t *erab_ctx)
+                                                        erab_ctx_t *erab_ctx,
+                                                        bool pack_attach)
 {
+
   int s1mme = m_s1ap->get_s1_mme();
 
   //Prepare reply PDU
@@ -159,16 +161,21 @@ s1ap_ctx_mngmt_proc::send_initial_context_setup_request(ue_emm_ctx_t *emm_ctx,
   m_s1ap_log->info_hex(emm_ctx->security_ctxt.k_enb, 32, "Initial Context Setup Request -- Key eNB\n");
 
   srslte::byte_buffer_t *nas_buffer = m_pool->allocate();
-  m_s1ap_nas_transport->pack_attach_accept(emm_ctx, ecm_ctx, erab_ctx_req, &erab_ctx->pdn_addr_alloc, nas_buffer); 
+  if(pack_attach)
+  {
+    pack_attach = false;
+    m_s1ap_nas_transport->pack_attach_accept(emm_ctx, ecm_ctx, erab_ctx_req, &erab_ctx->pdn_addr_alloc, nas_buffer); 
+
+  }
 
-  
   LIBLTE_ERROR_ENUM err = liblte_s1ap_pack_s1ap_pdu(&pdu, (LIBLTE_BYTE_MSG_STRUCT*)reply_buffer);
   if(err != LIBLTE_SUCCESS)
   {
     m_s1ap_log->error("Could not pack Initial Context Setup Request Message\n");
     return false;
   }
-  //Send Reply to eNB 
+
+  //Send Reply to eNB
   ssize_t n_sent = sctp_send(s1mme,reply_buffer->msg, reply_buffer->N_bytes, &ecm_ctx->enb_sri, 0);
   if(n_sent == -1)
   {

srsepc/src/mme/s1ap_nas_transport.cc

@@ -578,7 +578,7 @@ s1ap_nas_transport::handle_nas_guti_attach_request(  uint32_t enb_ue_s1ap_id,
         m_s1ap->add_new_ue_ecm_ctx(ue_ecm_ctx);
         //Create session request
         m_s1ap_log->console("GUTI Attach -- NAS Integrity OK.");
-        m_mme_gtpc->send_create_session_request(ue_emm_ctx->imsi, ue_emm_ctx->mme_ue_s1ap_id);
+        m_mme_gtpc->send_create_session_request(ue_emm_ctx->imsi, ue_emm_ctx->mme_ue_s1ap_id,true);
         *reply_flag = false; //No reply needed
         return true;
       }
@@ -652,7 +652,7 @@ s1ap_nas_transport::handle_nas_service_request(uint32_t m_tmsi,
       m_s1ap_log->info("Service Request -- User has ECM context already\n");
       m_s1ap->m_s1ap_ctx_mngmt_proc->send_ue_context_release_command(ecm_ctx,reply_buffer);
       int default_bearer_id = 5;
-      m_s1ap->m_s1ap_ctx_mngmt_proc->send_initial_context_setup_request(ue_emm_ctx, ecm_ctx, &ecm_ctx->erabs_ctx[default_bearer_id]);
+      m_s1ap->m_s1ap_ctx_mngmt_proc->send_initial_context_setup_request(ue_emm_ctx, ecm_ctx, &ecm_ctx->erabs_ctx[default_bearer_id],false);
     }
     else
     {
@@ -685,7 +685,9 @@ s1ap_nas_transport::handle_nas_service_request(uint32_t m_tmsi,
       //Re-generate K_eNB
       liblte_security_generate_k_enb(ue_emm_ctx->security_ctxt.k_asme, ue_emm_ctx->security_ctxt.ul_nas_count, ue_emm_ctx->security_ctxt.k_enb);
       m_s1ap_log->info("Generating KeNB with UL NAS COUNT: %d\n",ue_emm_ctx->security_ctxt.ul_nas_count);
-      m_mme_gtpc->send_create_session_request(ue_ecm_ctx.imsi, ue_ecm_ctx.mme_ue_s1ap_id);
+
+      m_mme_gtpc->send_create_session_request(ue_ecm_ctx.imsi, ue_ecm_ctx.mme_ue_s1ap_id,false);
+      // m_s1ap->m_s1ap_ctx_mngmt_proc->send_initial_context_setup_request(ue_);
     }
   }
   else
@@ -798,7 +800,7 @@ s1ap_nas_transport::handle_nas_security_mode_complete(srslte::byte_buffer_t *nas
   {
     //FIXME The packging of GTP-C messages is not ready.
     //This means that GTP-U tunnels are created with function calls, as opposed to GTP-C.
-    m_mme_gtpc->send_create_session_request(ue_ecm_ctx->imsi, ue_ecm_ctx->mme_ue_s1ap_id);
+    m_mme_gtpc->send_create_session_request(ue_ecm_ctx->imsi, ue_ecm_ctx->mme_ue_s1ap_id,true);
     *reply_flag = false; //No reply needed
   }
   return true;
@@ -867,7 +869,7 @@ s1ap_nas_transport::handle_esm_information_response(srslte::byte_buffer_t *nas_m
 
   //FIXME The packging of GTP-C messages is not ready.
   //This means that GTP-U tunnels are created with function calls, as opposed to GTP-C.
-  m_mme_gtpc->send_create_session_request(ue_ecm_ctx->imsi, ue_ecm_ctx->mme_ue_s1ap_id);
+  m_mme_gtpc->send_create_session_request(ue_ecm_ctx->imsi, ue_ecm_ctx->mme_ue_s1ap_id,true);
   return true;
 }
 
@@ -1577,12 +1579,12 @@ s1ap_nas_transport::pack_attach_accept(ue_emm_ctx_t *ue_emm_ctx, ue_ecm_ctx_t *u
 
   //Set up LAI for combined EPS/IMSI attach
   //attach_accept.lai_present=false;
-  attach_accept.lai_present=true;
+  attach_accept.lai_present=false;
   attach_accept.lai.mcc = mcc;
   attach_accept.lai.mnc = mnc;
   attach_accept.lai.lac = 001;
 
-  attach_accept.ms_id_present=true;
+  attach_accept.ms_id_present=false;
   attach_accept.ms_id.type_of_id = LIBLTE_MME_MOBILE_ID_TYPE_TMSI;
   attach_accept.ms_id.tmsi = attach_accept.guti.guti.m_tmsi;
 

srsepc/src/spgw/spgw.cc

@@ -437,7 +437,7 @@ spgw::get_new_ue_ipv4()
 }
 
 void
-spgw::handle_create_session_request(struct srslte::gtpc_create_session_request *cs_req, struct srslte::gtpc_pdu *cs_resp_pdu)
+spgw::handle_create_session_request(struct srslte::gtpc_create_session_request *cs_req, struct srslte::gtpc_pdu *cs_resp_pdu, bool pack_attach)
 {
   srslte::gtpc_header *header = &cs_resp_pdu->header;
   srslte::gtpc_create_session_response *cs_resp = &cs_resp_pdu->choice.create_session_response;
@@ -492,7 +492,7 @@ spgw::handle_create_session_request(struct srslte::gtpc_create_session_request *
   cs_resp->paa.ipv4_present = true;
   cs_resp->paa.ipv4 = ue_ip;
   m_spgw_log->info("Sending Create Session Response\n");
-  m_mme_gtpc->handle_create_session_response(cs_resp_pdu);
+  m_mme_gtpc->handle_create_session_response(cs_resp_pdu, pack_attach );
   return;
 }