reception of RRC Setup as response to re-establishment request

openair2/LAYER2/NR_MAC_UE/config_ue.c

@@ -1352,8 +1352,7 @@ static void configure_common_BWP_ul(NR_UE_MAC_INST_t *mac, int bwp_id, NR_BWP_Up
   }
 }
 
-void nr_rrc_mac_config_req_reset(module_id_t module_id,
-                                 NR_UE_MAC_reset_cause_t cause)
+void nr_rrc_mac_config_req_reset(module_id_t module_id, NR_UE_MAC_reset_cause_t cause)
 {
   NR_UE_MAC_INST_t *mac = get_mac_inst(module_id);
   if (cause == GO_TO_IDLE) {
@@ -1368,13 +1367,14 @@ void nr_rrc_mac_config_req_reset(module_id_t module_id,
     mac->ra.ra_state = RA_UE_IDLE;
   }
 
-  reset_mac_inst(mac);
+  if (cause != RRC_SETUP_NOT_FROM_IDLE)
+    reset_mac_inst(mac);
   nr_ue_mac_default_configs(mac);
   release_mac_configuration(mac, cause);
 
   // Sending to PHY a request to resync
   // with no target cell ID
-  if (cause != DETACH) {
+  if (cause != DETACH && cause != RRC_SETUP_NOT_FROM_IDLE) {
     mac->synch_request.Mod_id = module_id;
     mac->synch_request.CC_id = 0;
     mac->synch_request.synch_req.target_Nid_cell = -1;

openair2/LAYER2/NR_MAC_UE/mac_defs.h

@@ -169,7 +169,8 @@ typedef enum {
   GO_TO_IDLE,
   DETACH,
   T300_EXPIRY,
-  RE_ESTABLISHMENT
+  RE_ESTABLISHMENT,
+  RRC_SETUP_NOT_FROM_IDLE
 } NR_UE_MAC_reset_cause_t;
 
 typedef enum {

openair2/RRC/NR_UE/rrc_UE.c

@@ -874,7 +874,52 @@ static void nr_rrc_process_rrcsetup(NR_UE_RRC_INST_t *rrc,
 {
   // if the RRCSetup is received in response to an RRCReestablishmentRequest
   // or RRCResumeRequest or RRCResumeRequest1
-  // TODO none of the procedures implemented yet
+  if (rrc->ra_trigger == RRC_CONNECTION_REESTABLISHMENT || rrc->ra_trigger == RRC_RESUME_REQUEST) {
+    LOG_W(NR_RRC, "[UE %ld] Recived RRC Setup in response to %s request\n",
+          rrc->ue_id, rrc->ra_trigger == RRC_CONNECTION_REESTABLISHMENT ? "re-establishment" : "resume");
+
+    // discard any stored UE Inactive AS context and suspendConfig
+    // TODO
+
+    // discard any current AS security context including
+    // K_RRCenc key, the K_RRCint key, the K_UPint key and the K_UPenc key
+    // TODO only kgnb is stored
+    memset(rrc->kgnb, 0, sizeof(rrc->kgnb));
+    rrc->as_security_activated = false;
+
+    // release radio resources for all established RBs except SRB0,
+    // including release of the RLC entities, of the associated PDCP entities and of SDAP
+    rrcPerNB_t *nb = &rrc->perNB[gNB_index];
+    for (int i = 0; i < MAX_DRBS_PER_UE; i++) {
+      if (nb->status_DRBs[i] != RB_NOT_PRESENT) {
+        nb->status_DRBs[i] = RB_NOT_PRESENT;
+        nr_pdcp_release_drb(rrc->ue_id, i + 1);
+      }
+    }
+    for (int i = 1; i < NR_NUM_SRB; i++) {
+      if (nb->Srb[i] != RB_NOT_PRESENT) {
+        nb->Srb[i] = RB_NOT_PRESENT;
+        nr_pdcp_release_srb(rrc->ue_id, i);
+      }
+    }
+    for (int i = 0; i < NR_MAX_NUM_LCID; i++) {
+      if (nb->active_RLC_entity[i]) {
+        nb->active_RLC_entity[i] = false;
+        nr_rlc_release_entity(rrc->ue_id, i);
+      }
+    }
+    // release the RRC configuration except for the default L1 parameter values,
+    // default MAC Cell Group configuration and CCCH configuration
+    // TODO to be completed
+    NR_UE_MAC_reset_cause_t cause = RRC_SETUP_NOT_FROM_IDLE;
+    nr_rrc_mac_config_req_reset(rrc->ue_id, cause);
+
+    // indicate to upper layers fallback of the RRC connection
+    // TODO
+
+    // stop timer T380, if running
+    // TODO not implemented yet
+  }
 
   // perform the cell group configuration procedure in accordance with the received masterCellGroup
   nr_rrc_ue_process_masterCellGroup(rrc,
@@ -902,6 +947,8 @@ static void nr_rrc_process_rrcsetup(NR_UE_RRC_INST_t *rrc,
   // enter RRC_CONNECTED
   rrc->nrRrcState = RRC_STATE_CONNECTED_NR;
 
+  rrc->ra_trigger = RA_NOT_RUNNING;
+
   // set the content of RRCSetupComplete message
   // TODO procedues described in 5.3.3.4 seems more complex than what we actualy do
   rrc_ue_generate_RRCSetupComplete(rrc, rrcSetup->rrc_TransactionIdentifier);
@@ -1198,8 +1245,10 @@ static void nr_rrc_ue_process_RadioBearerConfig(NR_UE_RRC_INST_t *ue_rrc,
   if (LOG_DEBUGFLAG(DEBUG_ASN1))
     xer_fprint(stdout, &asn_DEF_NR_RadioBearerConfig, (const void *)radioBearerConfig);
 
-  if (radioBearerConfig->srb3_ToRelease)
+  if (radioBearerConfig->srb3_ToRelease) {
     nr_pdcp_release_srb(ue_rrc->ue_id, 3);
+    rrcNB->Srb[3] = RB_NOT_PRESENT;
+  }
 
   uint8_t kRRCenc[16] = {0};
   uint8_t kRRCint[16] = {0};
@@ -1245,8 +1294,10 @@ static void nr_rrc_ue_process_RadioBearerConfig(NR_UE_RRC_INST_t *ue_rrc,
   if (radioBearerConfig->drb_ToReleaseList) {
     for (int cnt = 0; cnt < radioBearerConfig->drb_ToReleaseList->list.count; cnt++) {
       NR_DRB_Identity_t *DRB_id = radioBearerConfig->drb_ToReleaseList->list.array[cnt];
-      if (DRB_id)
+      if (DRB_id) {
         nr_pdcp_release_drb(ue_rrc->ue_id, *DRB_id);
+        rrcNB->status_DRBs[*DRB_id - 1] = RB_NOT_PRESENT;
+      }
     }
   }
 
@@ -1316,6 +1367,9 @@ static void nr_rrc_ue_process_rrcReestablishment(NR_UE_RRC_INST_t *rrc,
   // release the measurement gap configuration indicated by the measGapConfig, if configured
   rrcPerNB_t *rrcNB = rrc->perNB + gNB_index;
   asn1cFreeStruc(asn_DEF_NR_MeasGapConfig, rrcNB->measGapConfig);
+
+  rrc->ra_trigger = RA_NOT_RUNNING;
+
   // submit the RRCReestablishmentComplete message to lower layers for transmission
   nr_rrc_ue_generate_rrcReestablishmentComplete(rrc, rrcReestablishment);
 }

openair2/RRC/NR_UE/rrc_defs.h

@@ -104,6 +104,7 @@ typedef enum RA_trigger_e {
   RA_NOT_RUNNING,
   INITIAL_ACCESS_FROM_RRC_IDLE,
   RRC_CONNECTION_REESTABLISHMENT,
+  RRC_RESUME_REQUEST,
   DURING_HANDOVER,
   NON_SYNCHRONISED,
   TRANSITION_FROM_RRC_INACTIVE,