Incorrect 5GS Mobile identity in InitialUEMessage Registration request

[hug0lin]

Packetrusher sends in NGAP/NAS-5GS InitialUEMessages Registration request field "5GS Mobile Identity" with length=0. For 5GC, which make a correct field check (length should be 6 to n) this means refusal of registration.

As specified in TS 24.501 (Table 8.2.6.1.1) this field is mandatory for Registration Request with defined structure

I understand that the implementation of 5GS Mobile Identity is very complicated (see 9.11.3.4 5GS mobile identity options - SUCI, the 5G-GUTI, the IMEI, the IMEISV, the 5G-S-TMSI, the MAC address or the EUI-64.), but it would be useful to implement at least basic registration and de-registration using SUCI.

[linouxis9]

Hi @hug0lin! Thanks for opening this issue. This is weird as PacketRusher definitely supports Registration using SUCI (null-scheme encoded SUPI as SUCI without any Profile A or Profile B encryption though) or with 5G-GUTI / 5G-S-TMSI if it got an TMSI allocated following a registration using SUCI. All 5GC requires at least registration using SUCI, so it's weird it's not working for you. Could you share your PacketRusher configuration, logs as well a pcap if possible? I suspect a wrong PacketRusher's configuration (since for now the configuration is poorly validated). Thanks a lot! Valentin

[linouxis9]

Hi @hug0lin, Any updates on your issue? Thanks a lot! Valentin