Continuing to work on initial context setup request.

lib/include/srslte/asn1/gtpc.h

@@ -27,6 +27,10 @@
 #include <stdint.h>
 #include "srslte/asn1/gtpc_msg.h"
 
+//Helpful marcos to convert TEIDs (uint64_t) to/from network byte order
+#define HTONLL(x) ((1==htonl(1)) ? (x) : (((uint64_t)htonl((x) & 0xFFFFFFFFUL)) << 32) | htonl((uint32_t)((x) >> 32)))
+#define NTOHLL(x) ((1==ntohl(1)) ? (x) : (((uint64_t)ntohl((x) & 0xFFFFFFFFUL)) << 32) | ntohl((uint32_t)((x) >> 32)))
+
 namespace srslte{
 
 /*GTP-C Version*/

lib/include/srslte/asn1/gtpc_msg.h

@@ -202,7 +202,7 @@ struct gtpc_create_session_request
     struct gtpc_f_teid_ie s12_rnc_f_teid;
     bool s2b_u_epdg_f_teid_present;
     struct gtpc_f_teid_ie s2b_u_epdg_f_teid;
-  } bearer_context_created;		// M
+  } eps_bearer_context_created;		// M
   //bool bearer_context_deleted_present;
   //struct bearer_context_ bearer_context_deleted;		// C
   //bool trace_information_present;

srsepc/hdr/mme/mme_gtpc.h

@@ -46,7 +46,7 @@ public:
   void init();
 
   uint64_t get_new_ctrl_teid();
-  void send_create_session_request(uint64_t imsi, struct srslte::gtpc_pdu *cs_resp_pdu);
+  void send_create_session_request(uint64_t imsi, uint32_t mme_s1ap_id);
   void handle_create_session_response(srslte::gtpc_pdu *cs_resp_pdu);
 
 private:

srsepc/hdr/mme/s1ap.h

@@ -81,7 +81,7 @@ 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);
+  bool send_initial_context_setup_request(uint32_t mme_ue_s1ap_id, struct srslte::gtpc_create_session_response *cs_resp);
 
   void print_enb_ctx_info(const enb_ctx_t &enb_ctx);
 

srsepc/src/mme/mme_gtpc.cc

@@ -79,11 +79,14 @@ 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_pdu *cs_resp_pdu)
+mme_gtpc::send_create_session_request(uint64_t imsi, uint32_t mme_ue_s1ap_id)
 {
   struct srslte::gtpc_pdu cs_req_pdu;
   struct srslte::gtpc_create_session_request *cs_req = &cs_req_pdu.choice.create_session_request;
 
+  struct srslte::gtpc_pdu cs_resp_pdu;
+ 
+
   //Initialize GTP-C message to zero
   bzero(&cs_req_pdu, sizeof(struct srslte::gtpc_pdu));
 
@@ -95,7 +98,7 @@ mme_gtpc::send_create_session_request(uint64_t imsi, struct srslte::gtpc_pdu *cs
 
   //Setup GTP-C Create Session Request IEs
   // Control TEID allocated \\
-  cs_req->sender_f_teid.tied = get_new_ctrl_teid();
+  cs_req->sender_f_teid.teid = get_new_ctrl_teid();
   cs_req->sender_f_teid.ipv4 = m_mme_gtpc_ip;
   // APN \\
   memcpy(cs_req->apn, "internet", sizeof("internet"));
@@ -103,20 +106,39 @@ mme_gtpc::send_create_session_request(uint64_t imsi, struct srslte::gtpc_pdu *cs
   cs_req->rat_type = GTPC_RAT_TYPE::EUTRAN;
 
   //Save RX Control TEID
-  //create_rx_control_teid(cs_req->sender_f_teid);
+  m_teid_to_mme_s1ap_id.insert(std::pair<uint64_t,uint32_t>(cs_req->sender_f_teid.teid, mme_ue_s1ap_id));
 
-  m_spgw->handle_create_session_request(cs_req, cs_resp_pdu);
-  return;
+  m_spgw->handle_create_session_request(cs_req, &cs_resp_pdu);
+  handle_create_session_response(&cs_resp_pdu);
+ 
 }
 
 void
 mme_gtpc::handle_create_session_response(srslte::gtpc_pdu *cs_resp_pdu)
 {
+  struct srslte::gtpc_create_session_response *cs_resp = & cs_resp_pdu->choice.create_session_response;
+
+  if (cs_resp_pdu->header.type != srslte::GTPC_MSG_TYPE_CREATE_SESSION_RESPONSE)
+  {
+     //m_mme_gtpc_log->warning("Could not create GTPC session.\n");
+     //TODO Handle err
+     return;
+  }
+  if (cs_resp->cause.cause_value != srslte::GTPC_CAUSE_VALUE_REQUEST_ACCEPTED){
+    //m_mme_gtpc_log->warning("Could not create GTPC session.\n");
+    //TODO Handle error
+    return;
+  }
+
   //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);
+  if(id_it == m_teid_to_mme_s1ap_id.end())
+  {
+    //Could not find MME UE S1AP TEID
+    return;
+  }
   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);
+  m_s1ap->send_initial_context_setup_request(mme_s1ap_id, cs_resp);
 }
 
 } //namespace srsepc

srsepc/src/mme/s1ap.cc

@@ -50,7 +50,7 @@ s1ap::get_instance(void)
 {
   boost::mutex::scoped_lock lock(s1ap_instance_mutex);
   if(NULL == m_instance) {
-    m_instance = new mme();
+    m_instance = new s1ap();
   }
   return(m_instance);
 }
@@ -538,37 +538,41 @@ 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_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, ue_ctx->mme_ue_s1ap_id);
 
-  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);
-  }
   return true;
 }
 
 bool
-s1ap::send_initial_context_setup_request(struct srslte::gtpc_create_session_response *cs_resp)
+s1ap::send_initial_context_setup_request(uint32_t mme_ue_s1ap_id, struct srslte::gtpc_create_session_response *cs_resp)
 {
 
+  //Find UE Context
+  ue_ctx_t *ue_ctx;
+  std::map<uint32_t, ue_ctx_t*>::iterator ue_ctx_it = m_active_ues.find(mme_ue_s1ap_id);
+  if(ue_ctx_it == m_active_ues.end())
+  {
+    m_s1ap_log->error("Could not find UE to send Setup Context Request. MME S1AP Id: %d", mme_ue_s1ap_id);
+    return false;
+  }
+  ue_ctx = ue_ctx_it->second;
+
   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 = ;
-  in_ctxt_req.eNB_UE_S1AP_ID =;
-  in_ctxt_req.uEaggregateMaximumBitrate =;
-
+  in_ctxt_req.MME_UE_S1AP_ID.MME_UE_S1AP_ID = ue_ctx->mme_ue_s1ap_id;
+  in_ctxt_req.eNB_UE_S1AP_ID.ENB_UE_S1AP_ID = ue_ctx->enb_ue_s1ap_id;
+  in_ctxt_req.uEaggregateMaximumBitrate.uEaggregateMaximumBitRateDL.BitRate=4294967295;//2^32-1
+  in_ctxt_req.uEaggregateMaximumBitrate.uEaggregateMaximumBitRateUL.BitRate=4294967295;//FIXME Get UE-AMBR from HSS
   //eRAB context to setup
-  LIBLTE_S1AP_E_RABSETUPITEMCTXTSURES_STRUCT *erab_ctxt = &in_ctxt_req.E_RABToBeSetupListCtxtSUReq.buffer[0]; //FIXME?
-  erab_ctxt->e_RAB_ID = cs_resp->bearer_context_created.ebi;
-  erab_ctxt->transportLayerAddress = cs_resp->bearer_context_created.sender_f_teid.ipv4;
-  erab_ctxt->gTP_TEID = cs_resp->bearer_context_created.sender_f_teid.teid;
+  LIBLTE_S1AP_E_RABTOBESETUPITEMCTXTSUREQ_STRUCT *erab_ctxt = &in_ctxt_req.E_RABToBeSetupListCtxtSUReq.buffer[0]; //FIXME?
+  erab_ctxt->e_RAB_ID.E_RAB_ID = cs_resp->eps_bearer_context_created.ebi;
+  if (cs_resp->eps_bearer_context_created.s1_u_sgw_f_teid_present == false){
+    m_s1ap_log->error("Did not receive S1-U TEID in create session response\n");
+    return false;
+  }
+  erab_ctxt->transportLayerAddress = cs_resp->eps_bearer_context_created.s1_u_sgw_f_teid.ipv4;
+  memcpy(erab_ctxt->gTP_TEID.buffer, cs_resp->eps_bearer_context_created.sender_f_teid.teid, sizeof(uint64_t));
 
   in_ctxt_req->UESecurityCapabilities =;
   in_ctxt_req->SecurityKey = ;
@@ -589,6 +593,17 @@ s1ap::send_initial_context_setup_request(struct srslte::gtpc_create_session_resp
     bool                                                         iE_Extensions_present;
   }LIBLTE_S1AP_E_RABSETUPITEMCTXTSURES_STRUCT;
   */
+  /*typedef struct{
+    bool     ext;
+    uint32_t n_bits;
+    uint8_t  buffer[160];
+  }LIBLTE_S1AP_TRANSPORTLAYERADDRESS_STRUCT;
+  */
+  /*
+  typedef struct{
+    uint8_t  buffer[4];
+  }LIBLTE_S1AP_GTP_TEID_STRUCT;
+  */
   /*typedef struct{
   bool                                                         ext;
   LIBLTE_S1AP_MME_UE_S1AP_ID_STRUCT                            MME_UE_S1AP_ID;