Changed S1AP to singleton. Continuing to work on the intial context setup request. Added a TEID to MME_UE_S1AP_ID map.

lib/include/srslte/asn1/gtpc.h

@@ -72,6 +72,7 @@ const uint8_t GTPC_V2 = 2;
 typedef union gtpc_msg_choice
 {
   struct gtpc_create_session_request create_session_request;
+  struct gtpc_create_session_response create_session_response;
 } gtpc_msg_choice_t;
 
 /****************************************************************************

srsepc/hdr/mme/mme.h

@@ -76,7 +76,7 @@ private:
   mme();
   virtual ~mme();
   static mme *m_instance;
-  s1ap m_s1ap;
+  s1ap *m_s1ap;
 
   bool m_running;
   srslte::byte_buffer_pool *m_pool;

srsepc/hdr/mme/mme_gtpc.h

@@ -28,11 +28,14 @@
 
 #include "srslte/common/buffer_pool.h"
 #include <boost/thread/mutex.hpp>
-#include "spgw/spgw.h"
 #include "srslte/asn1/gtpc.h"
+
 namespace srsepc
 {
 
+class spgw;
+class s1ap;
+
 class mme_gtpc
 {
 public:
@@ -41,8 +44,10 @@ public:
   static void cleanup(void);
 
   void init();
-  void send_create_session_request(uint64_t imsi, struct srslte::gtpc_create_session_response *cs_resp);
+
   uint64_t get_new_ctrl_teid();
+  void send_create_session_request(uint64_t imsi, struct srslte::gtpc_pdu *cs_resp_pdu);
+  void handle_create_session_response(srslte::gtpc_pdu *cs_resp_pdu);
 
 private:
 
@@ -52,10 +57,13 @@ private:
 
   srslte::byte_buffer_pool *m_pool;
 
+  s1ap* m_s1ap;
   spgw* m_spgw;
   in_addr_t m_mme_gtpc_ip;
 
   uint64_t m_next_ctrl_teid;
+  std::map<uint64_t,uint32_t> m_teid_to_mme_s1ap_id;
+
 };
 
 }

srsepc/hdr/mme/s1ap.h

@@ -26,6 +26,7 @@
 #ifndef S1AP_H
 #define S1AP_H
 
+#include "srslte/asn1/gtpc.h"
 #include "srslte/asn1/liblte_s1ap.h"
 #include "srslte/asn1/liblte_mme.h"
 #include "srslte/common/common.h"
@@ -54,6 +55,10 @@ class s1ap
 public:
   s1ap();
   virtual ~s1ap();
+
+  static s1ap* get_instance();
+  static void cleanup();
+
   int enb_listen();
   int init(s1ap_args_t s1ap_args, srslte::log_filter *s1ap_log);
   void stop();
@@ -76,11 +81,14 @@ 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);
+  bool send_initial_context_setup_request(struct srslte::gtpc_create_session_response *cs_resp);
 
   void print_enb_ctx_info(const enb_ctx_t &enb_ctx);
 
 private:
 
+  static s1ap *m_instance;
+
   s1ap_args_t                    m_s1ap_args;
   uint32_t                       m_plmn;
   srslte::byte_buffer_pool      *m_pool;

srsepc/hdr/spgw/spgw.h

@@ -43,6 +43,8 @@
 
 namespace srsepc{
 
+class mme_gtpc;
+
 const uint16_t GTPU_RX_PORT = 2152;
 
 typedef struct {
@@ -70,7 +72,7 @@ public:
   void stop();
   void run_thread();
 
-  void handle_create_session_request(struct srslte::gtpc_create_session_request *cs_req, struct srslte::gtpc_create_session_response *cs_resp);
+  void handle_create_session_request(struct srslte::gtpc_create_session_request *cs_req, struct srslte::gtpc_pdu *cs_resp_pdu);
 
 private:
 
@@ -86,6 +88,8 @@ private:
 
   bool m_running;
   srslte::byte_buffer_pool *m_pool;
+  mme_gtpc *m_mme_gtpc;
+
 
   bool m_sgi_up;
   int m_sgi_if;
@@ -96,6 +100,7 @@ private:
 
   uint64_t m_next_ctrl_teid;
   uint64_t m_next_user_teid;
+
   /*Logs*/
   srslte::log_filter  *m_spgw_log;
 

srsepc/src/mme/mme.cc

@@ -74,7 +74,8 @@ mme::init(mme_args_t* args, srslte::log_filter *s1ap_log)
 {
 
   /*Init S1AP*/
-  if(m_s1ap.init(args->s1ap_args, s1ap_log)){
+  m_s1ap = s1ap::get_instance();
+  if(m_s1ap->init(args->s1ap_args, s1ap_log)){
     m_s1ap_log->error("Error initializing MME S1APP\n");
     exit(-1);
   }
@@ -91,7 +92,8 @@ mme::stop()
 {
   if(m_running)
   {
-    m_s1ap.stop();
+    m_s1ap->stop();
+    m_s1ap->cleanup();
     m_running = false;
     thread_cancel();
     wait_thread_finish();
@@ -116,7 +118,7 @@ mme::run_thread()
   m_running=true;
 
   //Get S1-MME socket
-  int s1mme = m_s1ap.get_s1_mme();
+  int s1mme = m_s1ap->get_s1_mme();
   while(m_running)
   {
     m_s1ap_log->debug("Waiting for SCTP Msg\n");
@@ -138,7 +140,7 @@ mme::run_thread()
         {
           m_s1ap_log->info("SCTP Association Shutdown. Association: %d\n",sri.sinfo_assoc_id);
           m_s1ap_log->console("SCTP Association Shutdown. Association: %d\n",sri.sinfo_assoc_id);
-          m_s1ap.delete_enb_ctx(sri.sinfo_assoc_id);
+          m_s1ap->delete_enb_ctx(sri.sinfo_assoc_id);
         }
       }
       else
@@ -146,7 +148,7 @@ mme::run_thread()
         //Received data
         pdu->N_bytes = rd_sz;
         m_s1ap_log->info("Received S1AP msg. Size: %d\n", pdu->N_bytes);
-        m_s1ap.handle_s1ap_rx_pdu(pdu,&sri);
+        m_s1ap->handle_s1ap_rx_pdu(pdu,&sri);
       }
     }
   }

srsepc/src/mme/mme_gtpc.cc

@@ -27,6 +27,8 @@
 #include <iostream>
 #include "srslte/asn1/gtpc.h"
 #include "mme/mme_gtpc.h"
+#include "mme/s1ap.h"
+#include "spgw/spgw.h"
 
 namespace srsepc{
 
@@ -66,6 +68,7 @@ mme_gtpc::cleanup(void)
 void
 mme_gtpc::init()
 {
+  m_s1ap = s1ap::get_instance();
   m_mme_gtpc_ip = inet_addr("127.0.0.1");//FIXME At the moment, the GTP-C messages are not sent over the wire. So this parameter is not used.
   m_spgw = spgw::get_instance();
 }
@@ -76,7 +79,7 @@ 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, struct srslte::gtpc_create_session_response *cs_resp)
+mme_gtpc::send_create_session_request(uint64_t imsi, struct srslte::gtpc_pdu *cs_resp_pdu)
 {
   struct srslte::gtpc_pdu cs_req_pdu;
   struct srslte::gtpc_create_session_request *cs_req = &cs_req_pdu.choice.create_session_request;
@@ -102,7 +105,18 @@ mme_gtpc::send_create_session_request(uint64_t imsi, struct srslte::gtpc_create_
   //Save RX Control TEID
   //create_rx_control_teid(cs_req->sender_f_teid);
 
-  m_spgw->handle_create_session_request(cs_req, cs_resp);
+  m_spgw->handle_create_session_request(cs_req, cs_resp_pdu);
   return;
 }
+
+void
+mme_gtpc::handle_create_session_response(srslte::gtpc_pdu *cs_resp_pdu)
+{
+  //Get MME_UE_S1AP_ID from the Ctrl TEID
+  std::map<uint64_t,uint32_t>::iterator id_it = m_teid_to_mme_s1ap_id.find(cs_resp_pdu->header.teid);
+  uint32_t mme_s1ap_id = id_it->second;
+
+  m_s1ap->send_intial_context_setup_request(mme_s1ap_id, &cs_resp_pdu->choice.create_session_request);
+}
+
 } //namespace srsepc

srsepc/src/mme/s1ap.cc

@@ -32,6 +32,9 @@
 
 namespace srsepc{
 
+s1ap*          s1ap::m_instance = NULL;
+boost::mutex   s1ap_instance_mutex;
+
 s1ap::s1ap():
   m_s1mme(-1),
   m_next_mme_ue_s1ap_id(1)
@@ -42,6 +45,27 @@ s1ap::~s1ap()
 {
 }
 
+s1ap*
+s1ap::get_instance(void)
+{
+  boost::mutex::scoped_lock lock(s1ap_instance_mutex);
+  if(NULL == m_instance) {
+    m_instance = new mme();
+  }
+  return(m_instance);
+}
+
+void
+s1ap::cleanup(void)
+{
+  boost::mutex::scoped_lock lock(s1ap_instance_mutex);
+  if(NULL != m_instance) {
+    delete m_instance;
+    m_instance = NULL;
+  }
+}
+
+
 int
 s1ap::init(s1ap_args_t s1ap_args, srslte::log_filter *s1ap_log)
 {
@@ -514,23 +538,26 @@ s1ap::handle_nas_security_mode_complete(srslte::byte_buffer_t *nas_msg, srslte::
 
   //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.
-  struct srslte::gtpc_create_session_response cs_resp;
-  m_mme_gtpc->send_create_session_request(ue_ctx->imsi, &cs_resp);
-  if (cs_resp.cause.cause_value != srslte::GTPC_CAUSE_VALUE_REQUEST_ACCEPTED){
+  struct srslte::gtpc_pdu cs_resp_pdu;
+  struct srslte::gtpc_create_session_response *cs_resp = & cs_resp_pdu.choice.create_session_response;
+
+  m_mme_gtpc->send_create_session_request(ue_ctx->imsi, &cs_resp_pdu);
+  if (cs_resp->cause.cause_value != srslte::GTPC_CAUSE_VALUE_REQUEST_ACCEPTED){
     m_s1ap_log->warning("Could not create GTPC session.\n");
     //TODO Handle error
   }
   else{
-    send_initial_context_setup_request(&cs_resp);
+    send_initial_context_setup_request(cs_resp);
   }
   return true;
 }
 
 bool
-s1ap::send_initial_context_setup_request(struct srslte::create_session_response *cs_resp)
+s1ap::send_initial_context_setup_request(struct srslte::gtpc_create_session_response *cs_resp)
 {
 
   LIBLTE_S1AP_MESSAGE_INITIALCONTEXTSETUPREQUEST_STRUCT in_ctxt_req;
+  uint64_t imsi = m_mme_gtpc->ctrl_teid_to_imsi();
   bzero(&in_ctxt_req, sizeof(in_ctxt_req));
 
   in_ctxt_req.MME_UE_S1AP_ID = ;

srsepc/src/spgw/spgw.cc

@@ -34,6 +34,7 @@
 #include <linux/if.h>
 #include <linux/if_tun.h>
 #include "spgw/spgw.h"
+#include "mme/mme_gtpc.h"
 
 
 namespace srsepc{
@@ -86,6 +87,7 @@ spgw::init(spgw_args_t* args, srslte::log_filter *spgw_log)
 
   //Init log
   m_spgw_log = spgw_log;
+  m_mme_gtpc = mme_gtpc::get_instance();
 
   //Init SGi interface
   err = init_sgi_if(args);
@@ -306,8 +308,18 @@ spgw::get_new_ue_ipv4()
 }
 
 void
-spgw::handle_create_session_request(struct srslte::gtpc_create_session_request *cs_req, struct srslte::gtpc_create_session_response *cs_resp)
+spgw::handle_create_session_request(struct srslte::gtpc_create_session_request *cs_req, struct srslte::gtpc_pdu *cs_resp_pdu)
 {
+  srslte::gtpc_header *header = &cs_resp_pdu->header;
+  srslte::gtpc_create_session_response *cs_resp = &cs_resp_pdu->choice.create_session_response;
+
+  //Setup GTP-C header
+  header->piggyback = false;
+  header->teid_present = true;
+  header->teid = cs_req->sender_f_teid.teid;  //Send create session requesponse to the CS Request TEID
+  header->type = srslte::GTPC_MSG_TYPE_CREATE_SESSION_RESPONSE;
+
+
   //Setup uplink control TEID
   uint64_t spgw_uplink_ctrl_teid = get_new_ctrl_teid();
   //Setup uplink user TEID
@@ -315,7 +327,7 @@ spgw::handle_create_session_request(struct srslte::gtpc_create_session_request *
   //Allocate UE IP
   in_addr_t ue_ip = get_new_ue_ipv4();
 
-  //Save the UE context //TODO!!!
+  //Save the UE IMSI to Ctrl TEID map //TODO!!!
 
   //Create session response message
   //Initialize to zero\\
@@ -337,7 +349,10 @@ spgw::handle_create_session_request(struct srslte::gtpc_create_session_request *
   cs_resp->paa.ipv4_present = true;
   cs_resp->paa.ipv4 = ue_ip;
 
+  m_mme_gtpc->handle_create_session_response(cs_resp_pdu);
   return;
 }
 
+
+
 } //namespace srsepc