When a UE that requests slices tries to connect and there are no slices configured, the reject message is:
5GMM cause = 0x7 (5GS Services not allowed)
however it should be:
5GMM cause = 0x3e (No network slices available)
All 5GMM cause value in reject message is reviewed in this commit
UDM may send a Deregistration Notification to AMF, to deregister
specific UE from the network - Network-Initiated Deregistration.
Deregistration procedure includes sending Deregistration Request to UE,
starting a timer T3522, releasing PDU sessions from SMF, releasing PCF
policies from PCF, and waiting for Deregistration Accept from UE.
Not yet implemented is:
- to prevent deregistration of UE in case it has any emergency sessions,
- page UE when UE is in IDLE mode.
According to TS 23.502, 4.2.2.2.2, AMF sends Registration event to UDM
in the following cases:
- If the AMF has changed since the last Registration procedure, or
- if the UE provides a SUPI which doesn't refer to a valid context in
the AMF,
- or if the UE registers to the same AMF it has already registered
to a non- 3GPP access (i.e. the UE is registered over a non-3GPP access
and initiates this Registration procedure to add a 3GPP access).
In case that UE re-registers to the network with a GUTI, it bypasses
authentication check to the AUSF. In this case, AMF does not send
Registration event to UDM.
Consequently, when UE deregisters again, AMF would send a Deregistration
Event to a UDM, which does not have a context for it.
3GPP standard does not say when AMF sends Deregistration Event to UDM,
only that it is optional.
These (De-)Registration events are for (de-)registering AMF to the UDM
for serving the UE. And not for (de-)registering UE itself for purpose
of tracking when UE is registered on the network.
This partially reverts commit 7be7029ac4
* [SBI] Fix converting PatchItem to JSON
* [UDR] Add support for endpoint for patching subscription data
Add support for PATCH HTTP method for the following endpoint:
/subscription-data/{ueId}/context-data/amf-3gpp-access
Currently does not change any data in the database.
* [UDM] Add support for endpoint for patching subscription data
Add support for the following endpoint, HTTP PATCH method:
/nudm-uecm/v1/{ueId}/registrations/amf-3gpp-access
The endpoint is used when UE deregisters from the core, and AMF
sends a subscription modification request with "purgeFlag" set.
* [UDM] Add check for same GUAMI when patching subscription data
* [AMF] Send deregistration event to UDM
When UE sends deregistration request, AMF needs to send a
Nudm_UECM_Deregistration request to UDM.
The order of requests is now the following:
- send PDU session release to SMF
- send deregistration event to UDM
- send AM policy control release to PCF
Confirmation for non-cleartext IE should only be applied
to the initial NAS message. Registration requests and Service requests
with UplinkNASTransport do not have to.
All process will be forcely exited if it failed to encode the S1AP/NGAP/GTP/PFCP message. It is to make sure there was no problem with the encoding of open5gs.
1. If UE does not use a NAS container for Non-cleartext IEs,
Open5GS AMF will send Registration reject message.
2. If UE sends Non-cleartext IEs without Integrity-protected,
Open5GS AMF will send Registration reject message.
3. If UE does not send NAS container in Security mode complete message,
Open5GS AMF will send Registration reject message.
The AMF shall assign a new 5G-GUTI for a particular UE:
a) during a successful initial registration procedure;
b) during a successful registration procedure
for mobility registration update; and
c) after a successful service request procedure invoked as a response
to a paging request from the network and before the release
of the N1 NAS signalling connection as specified in subclause 5.4.4.1.
The AMF should assign a new 5G-GUTI for a particular UE
during a successful registration procedure
for periodic registration update. The AMF may assign a new 5G-GUTI
at any time for a particular UE by performing
the generic UE configuration update procedure.
If both Delete-Session-Request/Response and
UEContextReleaseCommand/UEContextReleaseComplete are failed at the same time,
UE cannot attach to the EPC infinitely.
So, I've add the protection code
if timer expires when MME does not receive Delete-Session-Response.
In TS24.501 Ch 5.5.1.3.8 Abnormal cases on the network side
d) REGISTRATION REQUEST with 5GS registration type IE set to
"mobility registration updating" or "periodic registration updating"
received after the REGISTRATION ACCEPT message has been sent and
before the REGISTRATION COMPLETE message is received.
Since, we have to do this special case, it is desirable
to handle it directly inside the state(gmm-sm.c).
o Tester
1. UE registered to 5GS and can connect to internet.
2. Turn off the UE and turn on the UE immediately
3. UE send PDU session request message
without sending registration complete
o Analysis Result
1. UE sends registration request with unknown GUTI
2. AMF send registration accept without GUTI
3. UE skips the registration complete
So, we need the handler UL NAS Transport in this state.
Sukchan Lee
Bostjan Meglic
Bostjan Meglic