extend handover intraenb handover fsm to account for multiple C-RNTI CEs

srsenb/hdr/stack/rrc/rrc_mobility.h

@@ -140,12 +140,14 @@ private:
     uint32_t target_cell_id;
   };
   using unsuccessful_outcome_ev = std::false_type;
+  using recfg_complete_ev       = asn1::rrc::rrc_conn_recfg_complete_s;
 
   // states
   struct idle_st {};
   struct intraenb_ho_st {
     const cell_info_common*    target_cell      = nullptr;
     const cell_ctxt_dedicated* source_cell_ctxt = nullptr;
+    uint16_t                   last_temp_crnti  = SRSLTE_INVALID_RNTI;
 
     void enter(rrc_mobility* f);
   };
@@ -190,7 +192,8 @@ private:
   // FSM transition handlers
   void handle_s1_meas_report(idle_st& s, s1_source_ho_st& d, const ho_meas_report_ev& meas_report);
   void handle_intraenb_meas_report(idle_st& s, intraenb_ho_st& d, const ho_meas_report_ev& meas_report);
-  void handle_crnti_ce(intraenb_ho_st& s, idle_st& d, const user_crnti_upd_ev& ev);
+  void handle_crnti_ce(intraenb_ho_st& s, intraenb_ho_st& d, const user_crnti_upd_ev& ev);
+  void handle_recfg_complete(intraenb_ho_st& s, idle_st& d, const recfg_complete_ev& ev);
 
 protected:
   // states
@@ -205,10 +208,11 @@ protected:
   // clang-format off
   using transitions = transition_table<
   //      Start        Target             Event              Action                            Guard (optional)
-    // +------------+---------------+--------------------+---------------------------------+---------------------------+
+  // +---------------+----------------+--------------------+---------------------------------+-------------------------+
-    row< idle_st,    intraenb_ho_st,  ho_meas_report_ev, &fsm::handle_intraenb_meas_report,  &fsm::needs_intraenb_ho   >,
   row< idle_st,        s1_source_ho_st, ho_meas_report_ev, &fsm::handle_s1_meas_report,        &fsm::needs_s1_ho       >,
-    row< intraenb_ho_st, idle_st,     user_crnti_upd_ev, &fsm::handle_crnti_ce                                         >
+  row< idle_st,        intraenb_ho_st,  ho_meas_report_ev, &fsm::handle_intraenb_meas_report,  &fsm::needs_intraenb_ho >,
+  row< intraenb_ho_st, intraenb_ho_st,  user_crnti_upd_ev, &fsm::handle_crnti_ce                                       >,
+  row< intraenb_ho_st, idle_st,         recfg_complete_ev, &fsm::handle_recfg_complete                                 >
   >;
   // clang-format on
 };

srsenb/src/stack/rrc/rrc_mobility.cc

@@ -958,6 +958,7 @@ void rrc::ue::rrc_mobility::intraenb_ho_st::enter(rrc_mobility* f)
     f->trigger(srslte::failure_ev{});
     return;
   }
+  last_temp_crnti = SRSLTE_INVALID_RNTI;
 
   /* Allocate Resources in Target Cell */
   // NOTE: for intra-eNB Handover only CQI resources will change
@@ -993,10 +994,13 @@ void rrc::ue::rrc_mobility::intraenb_ho_st::enter(rrc_mobility* f)
   }
 }
 
-void rrc::ue::rrc_mobility::handle_crnti_ce(intraenb_ho_st& s, idle_st& d, const user_crnti_upd_ev& ev)
+void rrc::ue::rrc_mobility::handle_crnti_ce(intraenb_ho_st& s, intraenb_ho_st& d, const user_crnti_upd_ev& ev)
 {
   rrc_log->info("UE performing handover updated its temp-crnti=0x%x to rnti=0x%x\n", ev.temp_crnti, ev.crnti);
+  bool is_first_crnti_ce = s.last_temp_crnti == SRSLTE_INVALID_RNTI;
+  s.last_temp_crnti      = ev.temp_crnti;
 
+  if (is_first_crnti_ce) {
     // Need to reset SNs of bearers.
     rrc_enb->pdcp->rem_user(rrc_ue->rnti);
     rrc_enb->pdcp->add_user(rrc_ue->rnti);
@@ -1011,8 +1015,15 @@ void rrc::ue::rrc_mobility::handle_crnti_ce(intraenb_ho_st& s, idle_st& d, const
     rrc_ue->ue_security_cfg.regenerate_keys_handover(s.target_cell->cell_cfg.pci, s.target_cell->cell_cfg.dl_earfcn);
     rrc_ue->bearer_list.reest_bearers();
     rrc_ue->bearer_list.apply_pdcp_bearer_updates(rrc_enb->pdcp, rrc_ue->ue_security_cfg);
+  } else {
+    rrc_log->info("Received duplicate C-RNTI CE during rnti=0x%x handover.\n", rrc_ue->rnti);
+  }
+}
 
-  rrc_log->info("new rnti=0x%x PCell is %d\n", ev.crnti, s.target_cell->enb_cc_idx);
+void rrc::ue::rrc_mobility::handle_recfg_complete(intraenb_ho_st& s, idle_st& d, const recfg_complete_ev& ev)
+{
+  rrc_log->info(
+      "User rnti=0x%x successfully handovered to cell_id=0x%x\n", rrc_ue->rnti, s.target_cell->cell_cfg.cell_id);
 }
 
 } // namespace srsenb

srsenb/src/stack/rrc/rrc_ue.cc

@@ -652,6 +652,9 @@ void rrc::ue::handle_rrc_reconf_complete(rrc_conn_recfg_complete_s* msg, srslte:
 
     // Flag completion of RadioResource Configuration
     bearer_list.rr_ded_cfg_complete();
+
+    // If performing handover, signal its completion
+    mobility_handler->trigger(*msg);
   } else {
     parent->rrc_log->error("Expected RRCReconfigurationComplete with transaction ID: %d, got %d\n",
                            last_rrc_conn_recfg.rrc_transaction_id,