Adding release access bearers request.

lib/include/srslte/asn1/gtpc.h

@@ -52,16 +52,15 @@ const uint8_t GTPC_V2 = 2;
  * n+2    |           Sequence            |
  * n+3    |            Spare              |
  ***************************************************************************/
-
-  typedef struct gtpc_header
-  {
+typedef struct gtpc_header
+{
   uint8_t version;
   bool piggyback;
   bool teid_present;
   uint8_t type;
   uint64_t teid;
   uint64_t sequence;
-  } gtpc_header_t;
+}gtpc_header_t;
 
 /****************************************************************************
  * GTP-C v2 Payload
@@ -69,16 +68,17 @@ const uint8_t GTPC_V2 = 2;
  *
  * Union that hold the different structures for the possible message types.
  ***************************************************************************/
-
 typedef union gtpc_msg_choice
 {
   struct gtpc_create_session_request create_session_request;
   struct gtpc_create_session_response create_session_response;
   struct gtpc_modify_bearer_request modify_bearer_request;
   struct gtpc_modify_bearer_response modify_bearer_response;
+  struct gtpc_release_access_bearers_request release_access_bearers_request;
+  struct gtpc_release_access_bearers_response release_access_bearers_response;
   struct gtpc_delete_session_request delete_session_request;
   struct gtpc_delete_session_response delete_session_response;
-} gtpc_msg_choice_t;
+}gtpc_msg_choice_t;
 
 /****************************************************************************
  * GTP-C v2 Message
@@ -88,15 +88,10 @@ typedef union gtpc_msg_choice
  * of one GTP-C header and one union of structures, which can hold
  * all the possible GTP-C messages
  ***************************************************************************/
-
 typedef struct gtpc_pdu
 {
   struct gtpc_header header;
   union gtpc_msg_choice choice;
-} gtpc_pdu_t;
-
-
-
-};
-
+}gtpc_pdu_t;
+}//namespace
 #endif

lib/include/srslte/asn1/gtpc_msg.h

@@ -410,5 +410,36 @@ struct gtpc_delete_session_response
   //Private extension
 };
 
+/****************************************************************************
+ *
+ * GTP-C v2 Release Access Bearers Request
+ * Ref: 3GPP TS 29.274 v10.14.0 Table 7.2.21.1-1
+ *
+ ***************************************************************************/
+struct gtpc_release_access_bearers_request
+{
+  bool list_of_rabs_present;
+  //Linked EPS Bearer ID
+  bool originating_node_present;
+  //Indication Flags
+  //Private Extension
+};
+
+  /****************************************************************************
+   *
+   * GTP-C v2 Delete Session Response
+   * Ref: 3GPP TS 29.274 v10.14.0 Table 7.2.22.1-1
+   *
+   ***************************************************************************/
+
+  struct gtpc_release_access_bearers_response
+  {
+    struct gtpc_cause_ie cause;
+    //Recovery
+    //Private extension
+  };
+
+
+
 } //namespace
 #endif //GTPC_V2_MSG_H

srsepc/hdr/mme/mme_gtpc.h

@@ -56,6 +56,7 @@ public:
   void handle_create_session_response(srslte::gtpc_pdu *cs_resp_pdu, bool pack_attach);
   void send_modify_bearer_request(uint64_t imsi, erab_ctx_t *bearer_ctx);
   void handle_modify_bearer_response(srslte::gtpc_pdu *mb_resp_pdu);
+  void send_release_access_bearers_request(uint64_t imsi);
   void send_delete_session_request(uint64_t imsi);
 
 private:

srsepc/src/mme/mme_gtpc.cc

@@ -351,10 +351,6 @@ mme_gtpc::send_release_access_bearers_request(uint64_t imsi)
 {
   m_mme_gtpc_log->info("Sending GTP-C Delete Access Bearers Request\n");
   srslte::gtpc_pdu rel_req_pdu;
-  if(ecm_ctx->state != ECM_STATE_CONNECTED )
-  {
-    m_mme_gtpc_log->error("ECM State is not connected. No valid SGW Ctr TEID present\n");
-  }
   srslte::gtpc_f_teid_ie *sgw_ctrl_fteid = NULL;
 
   srslte::gtpc_header *header = &rel_req_pdu.header;
@@ -363,13 +359,12 @@ mme_gtpc::send_release_access_bearers_request(uint64_t imsi)
   header->type = srslte::GTPC_MSG_TYPE_RELEASE_ACCESS_BEARERS_REQUEST;
 
   srslte::gtpc_release_access_bearers_request *rel_req = &rel_req_pdu.choice.release_access_bearers_request;
-  del_req->cause.cause_value = srslte::GTPC_CAUSE_VALUE_ISR_DEACTIVATION;
   m_mme_gtpc_log->info("GTP-C Release Access Berarers Request -- S-GW Control TEID %d\n", sgw_ctrl_fteid->teid );
 
-  srslte::gtpc_pdu del_resp_pdu;
-  m_spgw->handle_delete_session_request(&del_req_pdu, &del_resp_pdu);
+  srslte::gtpc_pdu rel_resp_pdu;
+  m_spgw->handle_release_access_bearers_response(&del_req_pdu, &rel_resp_pdu);
 
-  //TODO Handle delete session response
+  //The GTP-C connection will not be torn down, just the user plane bearers.
   return;
 }
 } //namespace srsepc