support retransmission of identity request and check receicved identi…

…ty type (#50)
free5gc · Jan 3, 2022 · 2d6b9a8 · 2d6b9a8
1 parent e857bcd
commit 2d6b9a8
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Showing 7 changed files with 59 additions and 28 deletions.
diff --git a/context/amf_ue.go b/context/amf_ue.go
@@ -65,6 +65,7 @@ type AmfUe struct {
 	DeregistrationTargetAccessType     uint8 // only used when deregistration procedure is initialized by the network
 	RegistrationAcceptForNon3GPPAccess []byte
 	RetransmissionOfInitialNASMsg      bool
+	RequestIdentityType                uint8
 	/* Used for AMF relocation */
 	TargetAmfProfile *models.NfProfile
 	TargetAmfUri     string
@@ -178,6 +179,8 @@ type AmfUe struct {
 	T3550 *Timer
 	/* T3522 (for deregistration request) */
 	T3522 *Timer
+	/* T3570 (for identity request) */
+	T3570 *Timer
 	/* Ue Context Release Cause */
 	ReleaseCause map[models.AccessType]*CauseAll
 	/* T3502 (Assigned by AMF, and used by UE to initialize registration procedure) */

diff --git a/context/context.go b/context/context.go
@@ -73,6 +73,7 @@ type AMFContext struct {
 	T3550Cfg factory.TimerValue
 	T3560Cfg factory.TimerValue
 	T3565Cfg factory.TimerValue
+	T3570Cfg factory.TimerValue
 	Locality string
 }
 

diff --git a/factory/config.go b/factory/config.go
@@ -54,6 +54,7 @@ type Configuration struct {
 	T3550                           TimerValue                `yaml:"t3550"`
 	T3560                           TimerValue                `yaml:"t3560"`
 	T3565                           TimerValue                `yaml:"t3565"`
+	T3570                           TimerValue                `yaml:"t3570"`
 	Locality                        string                    `yaml:"locality,omitempty"`
 }
 

diff --git a/gmm/handler.go b/gmm/handler.go
@@ -1371,6 +1371,15 @@ func HandleIdentityResponse(ue *context.AmfUe, identityResponse *nasMessage.Iden
 	ue.GmmLog.Info("Handle Identity Response")
 
 	mobileIdentityContents := identityResponse.MobileIdentity.GetMobileIdentityContents()
+	if nasConvert.GetTypeOfIdentity(mobileIdentityContents[0]) != ue.RequestIdentityType {
+		return fmt.Errorf("Received identity type doesn't match request type")
+	}
+
+	if ue.T3570 != nil {
+		ue.T3570.Stop()
+		ue.T3570 = nil // clear the timer
+	}
+
 	switch nasConvert.GetTypeOfIdentity(mobileIdentityContents[0]) { // get type of identity
 	case nasMessage.MobileIdentity5GSTypeSuci:
 		var plmnId string

diff --git a/gmm/message/send.go b/gmm/message/send.go
@@ -84,6 +84,20 @@ func SendIdentityRequest(ue *context.RanUe, accessType models.AccessType, typeOf
 		return
 	}
 	ngap_message.SendDownlinkNasTransport(ue, nasMsg, nil)
+
+	amfUe.RequestIdentityType = typeOfIdentity
+
+	if context.AMF_Self().T3570Cfg.Enable {
+		cfg := context.AMF_Self().T3570Cfg
+		amfUe.T3570 = context.NewTimer(cfg.ExpireTime, cfg.MaxRetryTimes, func(expireTimes int32) {
+			amfUe.GmmLog.Warnf("T3570 expires, retransmit Identity Request (retry: %d)", expireTimes)
+			ngap_message.SendDownlinkNasTransport(ue, nasMsg, nil)
+		}, func() {
+			amfUe.GmmLog.Warnf("T3570 Expires %d times, abort identification procedure & ongoing 5GMM procedure",
+				cfg.MaxRetryTimes)
+			gmm_common.RemoveAmfUe(amfUe)
+		})
+	}
 }
 
 func SendAuthenticationRequest(ue *context.RanUe) {

diff --git a/gmm/sm.go b/gmm/sm.go
@@ -167,14 +167,15 @@ func Authentication(state *fsm.State, event fsm.EventType, args fsm.ArgsType) {
 		case nas.MsgTypeIdentityResponse:
 			if err := HandleIdentityResponse(amfUe, gmmMessage.IdentityResponse); err != nil {
 				logger.GmmLog.Errorln(err)
-			}
-			// update identity type used for reauthentication
-			mobileIdentityContents := gmmMessage.IdentityResponse.MobileIdentity.GetMobileIdentityContents()
-			amfUe.IdentityTypeUsedForRegistration = nasConvert.GetTypeOfIdentity(mobileIdentityContents[0])
+			} else {
+				// update identity type used for reauthentication
+				mobileIdentityContents := gmmMessage.IdentityResponse.MobileIdentity.GetMobileIdentityContents()
+				amfUe.IdentityTypeUsedForRegistration = nasConvert.GetTypeOfIdentity(mobileIdentityContents[0])
 
-			err := GmmFSM.SendEvent(state, AuthRestartEvent, fsm.ArgsType{ArgAmfUe: amfUe, ArgAccessType: accessType})
-			if err != nil {
-				logger.GmmLog.Errorln(err)
+				err := GmmFSM.SendEvent(state, AuthRestartEvent, fsm.ArgsType{ArgAmfUe: amfUe, ArgAccessType: accessType})
+				if err != nil {
+					logger.GmmLog.Errorln(err)
+				}
 			}
 		case nas.MsgTypeAuthenticationResponse:
 			if err := HandleAuthenticationResponse(amfUe, accessType, gmmMessage.AuthenticationResponse); err != nil {
@@ -327,30 +328,31 @@ func ContextSetup(state *fsm.State, event fsm.EventType, args fsm.ArgsType) {
 		case nas.MsgTypeIdentityResponse:
 			if err := HandleIdentityResponse(amfUe, gmmMessage.IdentityResponse); err != nil {
 				logger.GmmLog.Errorln(err)
-			}
-			switch amfUe.RegistrationType5GS {
-			case nasMessage.RegistrationType5GSInitialRegistration:
-				if err := HandleInitialRegistration(amfUe, accessType); err != nil {
-					logger.GmmLog.Errorln(err)
-					err = GmmFSM.SendEvent(state, ContextSetupFailEvent, fsm.ArgsType{
-						ArgAmfUe:      amfUe,
-						ArgAccessType: accessType,
-					})
-					if err != nil {
+			} else {
+				switch amfUe.RegistrationType5GS {
+				case nasMessage.RegistrationType5GSInitialRegistration:
+					if err := HandleInitialRegistration(amfUe, accessType); err != nil {
 						logger.GmmLog.Errorln(err)
+						err = GmmFSM.SendEvent(state, ContextSetupFailEvent, fsm.ArgsType{
+							ArgAmfUe:      amfUe,
+							ArgAccessType: accessType,
+						})
+						if err != nil {
+							logger.GmmLog.Errorln(err)
+						}
 					}
-				}
-			case nasMessage.RegistrationType5GSMobilityRegistrationUpdating:
-				fallthrough
-			case nasMessage.RegistrationType5GSPeriodicRegistrationUpdating:
-				if err := HandleMobilityAndPeriodicRegistrationUpdating(amfUe, accessType); err != nil {
-					logger.GmmLog.Errorln(err)
-					err = GmmFSM.SendEvent(state, ContextSetupFailEvent, fsm.ArgsType{
-						ArgAmfUe:      amfUe,
-						ArgAccessType: accessType,
-					})
-					if err != nil {
+				case nasMessage.RegistrationType5GSMobilityRegistrationUpdating:
+					fallthrough
+				case nasMessage.RegistrationType5GSPeriodicRegistrationUpdating:
+					if err := HandleMobilityAndPeriodicRegistrationUpdating(amfUe, accessType); err != nil {
 						logger.GmmLog.Errorln(err)
+						err = GmmFSM.SendEvent(state, ContextSetupFailEvent, fsm.ArgsType{
+							ArgAmfUe:      amfUe,
+							ArgAccessType: accessType,
+						})
+						if err != nil {
+							logger.GmmLog.Errorln(err)
+						}
 					}
 				}
 			}

diff --git a/util/init_context.go b/util/init_context.go
@@ -81,6 +81,7 @@ func InitAmfContext(context *context.AMFContext) {
 	context.T3550Cfg = configuration.T3550
 	context.T3560Cfg = configuration.T3560
 	context.T3565Cfg = configuration.T3565
+	context.T3570Cfg = configuration.T3570
 	context.Locality = configuration.Locality
 }