gnb,rrc: handle reestablishment complete

* add message handler
* rename internal calls

srsgnb/hdr/stack/rrc/rrc_nr_ue.h

@@ -66,7 +66,8 @@ public:
   void handle_rrc_reconfiguration_complete(const asn1::rrc_nr::rrc_recfg_complete_s& msg);
 
   /** TS 38.331 - 5.3.7 RRC connection reestablishment */
-  void handle_rrc_reest_request(const asn1::rrc_nr::rrc_reest_request_s& msg);
+  void handle_rrc_reestablishment_request(const asn1::rrc_nr::rrc_reest_request_s& msg);
+  void handle_rrc_reestablishment_complete(const asn1::rrc_nr::rrc_reest_complete_s& msg);
 
   /** TS 38.331 - 5.3.8 Connection Release */
   void send_rrc_release();

srsgnb/src/stack/rrc/rrc_nr.cc

@@ -548,6 +548,9 @@ void rrc_nr::handle_ul_dcch(uint16_t rnti, uint32_t lcid, srsran::const_byte_spa
     case ul_dcch_msg_type_c::c1_c_::types_opts::ul_info_transfer:
       u.handle_ul_information_transfer(ul_dcch_msg.msg.c1().ul_info_transfer());
       break;
+    case ul_dcch_msg_type_c::c1_c_::types_opts::rrc_reest_complete:
+      u.handle_rrc_reestablishment_complete(ul_dcch_msg.msg.c1().rrc_reest_complete());
+      break;
     default:
       log_rx_pdu_fail(rnti, srb_to_lcid(lte_srb::srb0), pdu, "Unsupported UL-CCCH message type", false);
       // TODO Remove user
@@ -577,7 +580,7 @@ void rrc_nr::handle_rrc_reest_request(uint16_t rnti, const asn1::rrc_nr::rrc_ree
     return;
   }
   ue& u = *ue_it->second;
-  u.handle_rrc_reest_request(msg);
+  u.handle_rrc_reestablishment_request(msg);
 }
 
 /*******************************************************************************

srsgnb/src/stack/rrc/rrc_nr_ue.cc

@@ -884,7 +884,7 @@ void rrc_nr::ue::handle_rrc_setup_request(const asn1::rrc_nr::rrc_setup_request_
   set_activity_timeout(UE_INACTIVITY_TIMEOUT);
 }
 
-void rrc_nr::ue::handle_rrc_reest_request(const asn1::rrc_nr::rrc_reest_request_s& msg)
+void rrc_nr::ue::handle_rrc_reestablishment_request(const asn1::rrc_nr::rrc_reest_request_s& msg)
 {
   uint32_t old_rnti = msg.rrc_reest_request.ue_id.c_rnti;
   uint16_t pci      = msg.rrc_reest_request.ue_id.pci;
@@ -954,32 +954,34 @@ void rrc_nr::ue::handle_rrc_reest_request(const asn1::rrc_nr::rrc_reest_request_
   srb_to_add_mod_s& srb1 = next_radio_bearer_cfg.srb_to_add_mod_list[0];
   srb1.srb_id            = 1;
 
+  // compute config and create SRB1 for new user
   asn1::rrc_nr::radio_bearer_cfg_s dummy_radio_bearer_cfg; // just to compute difference, it's never sent to UE
   compute_diff_radio_bearer_cfg(parent->cfg, radio_bearer_cfg, next_radio_bearer_cfg, dummy_radio_bearer_cfg);
-
-  // - Setup masterCellGroup
-  // - Derive master cell group config bearers
   fill_cellgroup_with_radio_bearer_cfg(parent->cfg, dummy_radio_bearer_cfg, next_cell_group_cfg);
 
   // send RRC Reestablishment message and restore bearer configuration
   send_connection_reest(old_ue->sec_ctx.get_ncc());
 
+  // store current bearer/cell config with configured SRB1
+  radio_bearer_cfg = next_radio_bearer_cfg;
+  cell_group_cfg   = next_cell_group_cfg;
+
   // recover all previously created bearers from old UE object for (later) reconfiguration
   next_radio_bearer_cfg = old_ue->radio_bearer_cfg;
   next_cell_group_cfg   = old_ue->cell_group_cfg;
 
   // Recover GTP-U tunnels and NGAP context
-  // parent->gtpu->mod_bearer_rnti(old_rnti, rnti);
+  parent->gtpu->mod_bearer_rnti(old_rnti, rnti);
   parent->ngap->user_mod(old_rnti, rnti);
 
   // Reestablish E-RABs of old rnti later, during ConnectionReconfiguration
   // bearer_list.reestablish_bearers(std::move(old_ue->bearer_list));
 
   // remove old RNTI
-  // old_ue->mac_ctrl.set_drb_activation(false);
-  // parent->rem_user_thread(old_rnti);
+  old_ue->deactivate_bearers();
+  parent->bearer_mapper->rem_user(old_rnti);
+  parent->task_sched.defer_task([this, old_rnti]() { parent->rem_user(old_rnti); });
 
-  // state = RRC_STATE_WAIT_FOR_CON_REEST_COMPLETE;
   set_activity_timeout(MSG5_RX_TIMEOUT);
 }
 
@@ -1215,6 +1217,20 @@ void rrc_nr::ue::handle_rrc_reconfiguration_complete(const asn1::rrc_nr::rrc_rec
   parent->ngap->ue_notify_rrc_reconf_complete(rnti, true);
 }
 
+void rrc_nr::ue::handle_rrc_reestablishment_complete(const asn1::rrc_nr::rrc_reest_complete_s& msg)
+{
+  // Register DRB again, TODO: combine/move to establish_eps_bearer()
+  for (const auto& drb : next_radio_bearer_cfg.drb_to_add_mod_list) {
+    uint16_t lcid = drb1_lcid;
+    parent->bearer_mapper->add_eps_bearer(rnti, lcid - 3, srsran::srsran_rat_t::nr, lcid);
+
+    logger.info("Established EPS bearer for LCID %u and RNTI 0x%x", lcid, rnti);
+  }
+
+  // send reconfiguration to reestablish SRB2 and all previously established DRBs
+  send_rrc_reconfiguration();
+}
+
 void rrc_nr::ue::send_rrc_release()
 {
   static const uint32_t release_delay = 60; // Taken from TS 38.331, 5.3.8.3