Starting to add Create Session Request function

lib/include/srslte/asn1/gtpc.h

@@ -146,6 +146,20 @@ const uint8_t GTPC_MSG_TYPE_MBMS_SESSION_STOP_RESPONSE = 236;
 //Other
 //240 - 255 For future use
 
+/****************************************************************************
+ * GTP-C v2 Message
+ * Ref: 3GPP TS 29.274 v10.14.0
+ *
+ * This is the main structure to represent a GTP-C message. It is composed
+ * 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;
+  union gtpc_msg_choice;
+} gtpc_pdu_t;
+
 /****************************************************************************
  * GTP-C v2 Header
  * Ref: 3GPP TS 29.274 v10.14.0 Section 5
@@ -176,6 +190,16 @@ typedef struct gtpc_header
   uint64_t sequence;
 } gtpc_header_t;
 
+/****************************************************************************
+ * GTP-C v2 Header
+ * Ref: 3GPP TS 29.274 v10.14.0 Section 5
+ *
+ * Union that hold the different structures for the possible message types.
+ ***************************************************************************/
+typedef union gtpc_msg_choice
+{
+  struct gtpc_create_session_request create_session_request;
+};
 
 /****************************************************************************
  *

srsepc/hdr/mme/mme_gtpc.h

@@ -0,0 +1,48 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2017 Software Radio Systems Limited
+ *
+ * \section LICENSE
+ *
+ * This file is part of srsLTE.
+ *
+ * srsLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * srsLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * A copy of the GNU Affero General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+#ifndef    MME_GTPC_H
+#define    MME_GTPC_H
+
+namespace srsepc
+{
+
+class mme_gtpc
+{
+public:
+  mme_gtpc();
+  ~mme_gtpc();
+
+  static mme_gtpc* get_instance(void);
+  static void cleanup(void);
+
+  void init();
+
+  void send_create_session_request(uint64_t imsi, struct create_session_response *cs_resp);
+
+};
+
+}
+#endif

srsepc/hdr/mme/s1ap.h

@@ -42,6 +42,7 @@
 #include "mme/s1ap_common.h"
 #include "mme/s1ap_mngmt_proc.h"
 #include "mme/s1ap_nas_transport.h"
+#include "mme/mme_gtpc.h"
 #include "hss/hss.h"
 
 namespace srsepc{
@@ -62,7 +63,6 @@ public:
   void delete_enb_ctx(int32_t assoc_id);
   void delete_ues_in_enb(uint16_t enb_id);
 
-  
   bool handle_s1ap_rx_pdu(srslte::byte_buffer_t *pdu, struct sctp_sndrcvinfo *enb_sri);
   bool handle_initiating_message(LIBLTE_S1AP_INITIATINGMESSAGE_STRUCT *msg, struct sctp_sndrcvinfo *enb_sri);
 
@@ -77,7 +77,6 @@ public:
   bool handle_nas_authentication_response(srslte::byte_buffer_t *nas_buffer, srslte::byte_buffer_t *reply_buffer, ue_ctx_t *ue_ctx);
   bool handle_nas_security_mode_complete(srslte::byte_buffer_t *nas_msg, srslte::byte_buffer_t *reply_msg, ue_ctx_t *ue_ctx);
 
-
   void print_enb_ctx_info(const enb_ctx_t &enb_ctx);
 
 private:
@@ -98,6 +97,9 @@ private:
 
   s1ap_mngmt_proc                m_s1ap_mngmt_proc;
   s1ap_nas_transport             m_s1ap_nas_transport;
+
+  //FIXME the GTP-C should be moved to the MME class, the the packaging of GTP-C messages is done.
+  mme_gtpc *m_gtpc;
 };
 
 

srsepc/src/mme/mme_gtpc.cc

@@ -0,0 +1,96 @@
+/**
+ *
+ * \section COPYRIGHT
+ *
+ * Copyright 2013-2017 Software Radio Systems Limited
+ *
+ * \section LICENSE
+ *
+ * This file is part of srsLTE.
+ *
+ * srsLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * srsLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * A copy of the GNU Affero General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#include <iostream>
+
+namespace srsepc{
+
+mme_gtpc*          mme_gtpc::m_instance = NULL;
+boost::mutex  mme_gtpc_instance_mutex;
+
+mme_gtpc::mme_gtpc():
+{
+}
+
+mme_gtpc::~mme_gtpc()
+{
+}
+
+mme_gtpc*
+mme_gtpc::get_instance(void)
+{
+  boost::mutex::scoped_lock lock(mme_gtpc_instance_mutex);
+  if(NULL == m_instance) {
+    m_instance = new mme_gtpc();
+  }
+  return(m_instance);
+}
+
+void
+mme_gtpc::cleanup(void)
+{
+  boost::mutex::scoped_lock lock(mme_gtpc_instance_mutex);
+  if(NULL != m_instance) {
+    delete m_instance;
+    m_instance = NULL;
+  }
+}
+
+
+void
+mme_gtpc::init()
+{
+  m_spgw = spgw::get_instance();
+}
+
+void
+mme_gtpc::send_create_session_request(uint64_t imsi, struct create_session_response *cs_resp)
+{
+  uint64_t imsi;
+  struct gtpc_pdu cs_req;
+
+  //Setup GTP-C Header. FIXME: Length, sequence and other fields need to be added.
+  cs_req.header.piggyback = false;
+  cs_req.header.teid_present = true;
+  cs_req.header.type = GTPC_MSG_TYPE_CREATE_SESSION_REQUEST;
+  cs_req.header.teid = 0; //Send create session request to the butler TEID
+
+  //Setup GTP-C Create Session Request IEs
+  // Control TEID allocated \\
+  cs_req.create_session_request.sender_f_teid.tied = get_new_ctrl_teid();
+  cs_req.create_session_request.sender_f_teid.ip = htonl(m_mme_ip);
+  // APN \\
+  memcpy(cs_req.create_session_request.apn, "internet", sizeof("internet"));
+  // RAT Type \\
+  cs_req.create_session_request.rat_type = GTPC_RAT_TYPE::EUTRAN;
+
+  //Save RX Control TEID
+  create_rx_control_teid(create_session_request.sender_f_tied);
+
+  spgw->handle_create_session_request(&cs_req, cs_resp);
+  return;
+}
+} //namespace srsepc

srsepc/src/mme/s1ap.cc

@@ -44,6 +44,7 @@ s1ap::~s1ap()
 int
 s1ap::init(s1ap_args_t s1ap_args, srslte::log_filter *s1ap_log)
 {
+  m_pool = srslte::byte_buffer_pool::get_instance();
 
   m_s1ap_args = s1ap_args;
   srslte::s1ap_mccmnc_to_plmn(s1ap_args.mcc, s1ap_args.mnc, &m_plmn);
@@ -52,7 +53,7 @@ s1ap::init(s1ap_args_t s1ap_args, srslte::log_filter *s1ap_log)
   m_s1ap_nas_transport.set_log(s1ap_log);
 
   m_hss = hss::get_instance();
-  m_pool = srslte::byte_buffer_pool::get_instance();
+  m_gtpc = mme_gtpc::get_instance();
 
   m_s1mme = enb_listen();
 
@@ -483,7 +484,11 @@ s1ap::handle_nas_authentication_response(srslte::byte_buffer_t *nas_msg, srslte:
     //Send Security Mode Command
     m_s1ap_nas_transport.pack_security_mode_command(reply_msg, ue_ctx);
 
-    //m_gtpc->send_create_session_request(ue_ctx->imsi);
+    //FIXME The packging of GTP-C messages is not ready
+    //This means that GTP-U tunnels are created with function calls, as oposed to GTP-C.
+    //In future send_create_session_request will return void and the handle_create_session_response will be called from the GTP-C class itself.
+    struct gtpc_create_session_response *cs_resp = m_gtpc->send_create_session_request(ue_ctx->imsi);
+    m_gtpc->handle_create_session_response(cs_resp);
   }
   return true;
 }