Allow registration to PLMNID other than 208-93

gnodeb/ngap/build.go

@@ -5,9 +5,13 @@
 package ngap
 
 import (
+	"encoding/binary"
 	"encoding/hex"
+	"errors"
 	"fmt"
+	"strconv"
 
+	"github.com/omec-project/aper"
 	gnbctx "github.com/omec-project/gnbsim/gnodeb/context"
 	"github.com/omec-project/gnbsim/util/ngapTestpacket"
 
@@ -65,6 +69,36 @@ func GetNGSetupRequest(gnb *gnbctx.GNodeB) ([]byte, error) {
 	return ngap.Encoder(message)
 }
 
+// GetInitialUEMessage encodes NGAP InitialUEMessage for the given UE.
+//
+//	gnbue: gNB-UE context.
+//	nasPdu: value of id-NAS-PDU from the UE.
+func GetInitialUEMessage(gnbue *gnbctx.GnbCpUe, nasPdu []byte) ([]byte, error) {
+	message := ngapTestpacket.BuildInitialUEMessage(gnbue.GnbUeNgapId, nasPdu, "")
+	ies := message.InitiatingMessage.Value.InitialUEMessage.ProtocolIEs.List
+
+	if e := updateUserLocationInformation(gnbue.Gnb, ies[2].Value.UserLocationInformation); e != nil {
+		return nil, e
+	}
+
+	return ngap.Encoder(message)
+}
+
+// GetUplinkNASTransport encodes NGAP UplinkNASTransport for the given UE.
+//
+//	gnbue: gNB-UE context.
+//	nasPdu: value of id-NAS-PDU from the UE.
+func GetUplinkNASTransport(gnbue *gnbctx.GnbCpUe, nasPdu []byte) ([]byte, error) {
+	message := ngapTestpacket.BuildUplinkNasTransport(gnbue.AmfUeNgapId, gnbue.GnbUeNgapId, nasPdu)
+	ies := message.InitiatingMessage.Value.UplinkNASTransport.ProtocolIEs.List
+
+	if e := updateUserLocationInformation(gnbue.Gnb, ies[3].Value.UserLocationInformation); e != nil {
+		return nil, e
+	}
+
+	return ngap.Encoder(message)
+}
+
 func GetUEContextReleaseRequest(gnbue *gnbctx.GnbCpUe) ([]byte, error) {
 	var pduSessIds []int64
 	f := func(k interface{}, v interface{}) bool {
@@ -85,3 +119,56 @@ func GetUEContextReleaseRequest(gnbue *gnbctx.GnbCpUe) ([]byte, error) {
 
 	return ngap.Encoder(message)
 }
+
+// GetUplinkNASTransport encodes NGAP UEContextReleaseComplete for the given UE.
+//
+//	gnbue: gNB-UE context.
+//	nasPdu: value of id-NAS-PDU from the UE.
+func GetUEContextReleaseComplete(gnbue *gnbctx.GnbCpUe) ([]byte, error) {
+	var pduSessIds []int64
+	gnbue.GnbUpUes.Range(func(k interface{}, v interface{}) bool {
+		pduSessIds = append(pduSessIds, k.(int64))
+		return true
+	})
+
+	message := ngapTestpacket.BuildUEContextReleaseComplete(gnbue.AmfUeNgapId, gnbue.GnbUeNgapId, pduSessIds)
+	ies := message.SuccessfulOutcome.Value.UEContextReleaseComplete.ProtocolIEs.List
+
+	if e := updateUserLocationInformation(gnbue.Gnb, ies[2].Value.UserLocationInformation); e != nil {
+		return nil, e
+	}
+
+	return ngap.Encoder(message)
+}
+
+// updateUserLocationInformation updates UserLocationInformation element to match gNB information.
+//
+//	gnb: gNB context.
+//	uli: UserLocationInformation prepared by ngapTestpacket package.
+func updateUserLocationInformation(gnb *gnbctx.GNodeB, uli *ngapType.UserLocationInformation) error {
+	nr := uli.UserLocationInformationNR
+
+	nr.NRCGI.PLMNIdentity = ngapConvert.PlmnIdToNgap(*gnb.RanId.PlmnId)
+	nr.TAI.PLMNIdentity = nr.NRCGI.PLMNIdentity
+
+	gnbID, e := strconv.ParseUint(gnb.RanId.GNbId.GNBValue, 16, 64)
+	if e != nil {
+		return fmt.Errorf("invalid GNB ID: %w", e)
+	}
+	// NRCI contains gnbID and cellID, here we assume cellID is zero
+	nrci := gnbID << uint64(36-gnb.RanId.GNbId.BitLength)
+	nrciBuf := [8]byte{}
+	binary.BigEndian.PutUint64(nrciBuf[:], nrci)
+	nr.NRCGI.NRCellIdentity.Value.Bytes = nrciBuf[3:]
+
+	if len(gnb.SupportedTaList) < 1 {
+		return errors.New("unexpected empty SupportedTaList")
+	}
+	tac, e := hex.DecodeString(gnb.SupportedTaList[0].Tac)
+	if e != nil {
+		return fmt.Errorf("invalid TAC: %w", e)
+	}
+	nr.TAI.TAC.Value = aper.OctetString(tac)
+
+	return nil
+}

gnodeb/worker/gnbcpueworker/handler.go

@@ -55,7 +55,7 @@ func HandleInitialUEMessage(gnbue *gnbctx.GnbCpUe,
 		}
 		gnbue.Log.Traceln("Sent Uplink NAS Message to AMF")
 	} else {
-		sendMsg, err := test.GetInitialUEMessage(gnbue.GnbUeNgapId, msg.NasPdus[0], "")
+		sendMsg, err := ngap.GetInitialUEMessage(gnbue, msg.NasPdus[0])
 		if err != nil {
 			gnbue.Log.Errorln("GetInitialUEMessage failed:", err)
 			return
@@ -113,7 +113,7 @@ func HandleUlInfoTransfer(gnbue *gnbctx.GnbCpUe,
 
 	msg := intfcMsg.(*common.UuMessage)
 	gnbue.Log.Traceln("Creating Uplink NAS Transport Message")
-	sendMsg, err := test.GetUplinkNASTransport(gnbue.AmfUeNgapId, gnbue.GnbUeNgapId, msg.NasPdus[0])
+	sendMsg, err := ngap.GetUplinkNASTransport(gnbue, msg.NasPdus[0])
 	if err != nil {
 		gnbue.Log.Errorln("GetUplinkNASTransport failed:", err)
 		return
@@ -427,15 +427,7 @@ func HandleUeCtxReleaseCommand(gnbue *gnbctx.GnbCpUe,
 		}
 	}
 
-	var pduSessIds []int64
-	f := func(k interface{}, v interface{}) bool {
-		pduSessIds = append(pduSessIds, k.(int64))
-		return true
-	}
-	gnbue.GnbUpUes.Range(f)
-
-	ngapPdu, err := test.GetUEContextReleaseComplete(gnbue.AmfUeNgapId,
-		gnbue.GnbUeNgapId, pduSessIds)
+	ngapPdu, err := ngap.GetUEContextReleaseComplete(gnbue)
 	if err != nil {
 		fmt.Println("Failed to create UE Context Release Complete message")
 		return

profile/profile.go

@@ -9,6 +9,7 @@ import (
 	"fmt"
 	"log"
 	"strconv"
+	"strings"
 	"sync"
 
 	"github.com/omec-project/gnbsim/common"
@@ -62,12 +63,18 @@ func InitProfile(profile *profctx.Profile, summaryChan chan common.InterfaceMess
 	}
 
 	for count := 1; count <= profile.UeCount; count++ {
-		imsiStr := IMSI_PREFIX + strconv.Itoa(startImsi)
+		imsiStr := makeImsiStr(profile, startImsi)
 		initImsi(profile, gnb, imsiStr)
 		startImsi++
 	}
 }
 
+// makeImsiStr constructs IMSI string with specified integer value and proper length.
+func makeImsiStr(profile *profctx.Profile, imsi int) string {
+	s := strconv.Itoa(imsi)
+	return IMSI_PREFIX + strings.Repeat("0", max(0, len(profile.StartImsi)-len(s))) + s
+}
+
 func initImsi(profile *profctx.Profile, gnb *gnbctx.GNodeB, imsiStr string) {
 	readChan := make(chan *common.ProfileMessage)
 	c := simue.InitUE(imsiStr, gnb, profile, readChan)
@@ -127,7 +134,7 @@ func ExecuteProfile(profile *profctx.Profile, summaryChan chan common.InterfaceM
 				plock.Lock()
 				profile.UeCount = profile.UeCount + 1
 				imsi := profile.Imsi + profile.UeCount
-				imsiStr := IMSI_PREFIX + strconv.Itoa(imsi)
+				imsiStr := makeImsiStr(profile, imsi)
 				initImsi(profile, gnb, imsiStr)
 				pCtx := profile.PSimUe[imsiStr]
 				profile.Log.Infoln("pCtx ", pCtx)
@@ -151,7 +158,7 @@ func ExecuteProfile(profile *profctx.Profile, summaryChan chan common.InterfaceM
 	}()
 	imsi := profile.Imsi
 	for count := 1; count <= profile.UeCount; count++ {
-		imsiStr := IMSI_PREFIX + strconv.Itoa(imsi)
+		imsiStr := makeImsiStr(profile, imsi)
 		imsi++
 		wg.Add(1)
 		pCtx := profile.PSimUe[imsiStr]

realue/handler.go

@@ -7,6 +7,7 @@ package realue
 import (
 	"fmt"
 	"net"
+	"strconv"
 
 	"github.com/omec-project/gnbsim/common"
 	realuectx "github.com/omec-project/gnbsim/realue/context"
@@ -25,9 +26,8 @@ import (
 
 // TODO Remove the hardcoding
 const (
-	SN_NAME                        string = "5G:mnc093.mcc208.3gppnetwork.org"
-	SWITCH_OFF                     uint8  = 0
-	REQUEST_TYPE_EXISTING_PDU_SESS uint8  = 0x02
+	SWITCH_OFF                     uint8 = 0
+	REQUEST_TYPE_EXISTING_PDU_SESS uint8 = 0x02
 )
 
 func HandleRegRequestEvent(ue *realuectx.RealUe,
@@ -64,9 +64,13 @@ func HandleAuthResponseEvent(ue *realuectx.RealUe,
 
 	ue.NgKsi = nasConvert.SpareHalfOctetAndNgksiToModels(authReq.SpareHalfOctetAndNgksi)
 
+	mcc, _ := strconv.Atoi(ue.Plmn.Mcc)
+	mnc, _ := strconv.Atoi(ue.Plmn.Mnc)
+	snName := fmt.Sprintf("5G:mnc%03d.mcc%03d.3gppnetwork.org", mnc, mcc)
+
 	rand := authReq.GetRANDValue()
 	autn := authReq.GetAUTN()
-	resStat := ue.DeriveRESstarAndSetKey(autn[:], rand[:], SN_NAME)
+	resStat := ue.DeriveRESstarAndSetKey(autn[:], rand[:], snName)
 
 	// TODO: Parse Auth Request IEs and update the RealUE Context
 

realue/util/util.go

@@ -23,25 +23,12 @@ const (
 var ROUTING_INDICATOR []uint8 = []uint8{0xf0, 0xff}
 
 func SupiToSuci(supi string, plmnid *models.PlmnId) ([]byte, error) {
-	index := strings.Index(supi, "-")
-	if index < 0 {
-		return nil, fmt.Errorf(`invalid supi format, should start with "imsi-"`)
+	supiExpectedPrefix := "imsi-" + plmnid.Mcc + plmnid.Mnc
+	if !strings.HasPrefix(supi, supiExpectedPrefix) {
+		return nil, fmt.Errorf(`invalid supi format, should start with "imsi-" + MCC + MNC`)
 	}
-
-	// extracting imsi part after "imsi-"
-	imsi := supi[(index + 1):]
-
-	if !strings.Contains(imsi, plmnid.Mcc) {
-		return nil, fmt.Errorf("mcc not found in imsi")
-	}
-
-	index = strings.Index(imsi, plmnid.Mnc)
-	if index < 0 {
-		return nil, fmt.Errorf("mnc not found in imsi")
-	}
-	index += len(plmnid.Mnc)
-	// extracting msin from imsi
-	msin := imsi[index:]
+	// extracting msin from supi
+	msin := supi[len(supiExpectedPrefix):]
 
 	suci := make([]uint8, 0, SUCI_LEN)
 	// creating octet 4 of 5GS mobile identity info