A UE RRCSetupRequest with establishmentCause in the spare range (10–15)
could abort nr-softmodem: RRC asserted on cause >= NGAP_RRC_CAUSE_LAST,
and cause 11 failed NGAP ASN.1 encode when passed through by index.
NR RRC (TS 38.331) and NGAP RRCEstablishmentCause (TS 38.413 §9.3.1.111)
do not share one integer namespace: spare values must not be sent
as NGAP causes.
Remove the RRC AssertFatal on causes. When building
InitialUEMessage, map RRC indices 0–9 to the matching NGAP cause
and map anything else to notAvailable, as specified for unmapped UE
causes.
Changes:
- Drop establishment-cause range AssertFatal in rrc_gNB_send_NGAP_NAS_FIRST_REQ
- Add rrc2ngap_establishment_cause() and use it for InitialUEMessage RRCEstablishmentCause
- Remove redundant DevCheck on establishment_cause in ngap_gNB_handle_nas_first_req
- Adopt mapping logic in rrc_gNB_send_NGAP_NAS_FIRST_REQ
Closes: #127
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
- all RAN code, CI code, configuration files, dockerfiles, in CSSL v1.0
- all deployment code (openshift, charts, ancillary files like shell
scripts), in MIT
- documentation in CC-BY-4.0
- exceptions might apply and are listed in NOTICE
- there is a new LICENSES folder with all licenses
- CONTRIBUTIONS.md has been updated accordingly
For automated changes based on OAI PL v1.1:
perl -i~ -0pe 's/\/\*.*Licensed to the OpenAirInterface.*openairinterface.org\n#?/\/*\n * SPDX-License-Identifier: LicenseRef-CSSL-1.0\n/s' **/*.{c,h,cpp}
perl -i~ -0pe 's/\/\*.*Licensed to the OpenAirInterface.*openairinterface.org\n#?/\/*\n * SPDX-License-Identifier: LicenseRef-CSSL-1.0\n/s' **/*.ts
perl -i~ -0pe 's/<!--.*Licensed to the OpenAirInterface.*openairinterface.org\n.*-->/<!-- SPDX-License-Identifier: LicenseRef-CSSL-1.0 -->/s' **/*.xml
The rest (cmake, files with missing license, cmake) manually.
Remove the \file directive, as it is always superfluous because the
current file is implicit [1]:
> If the file name is omitted (i.e. the line after \file is left blank)
> then the documentation block that contains the \file command will belong
> to the file it is located in.
Author names and e-mails are not relevant for us: it can always be
inferred from git blame, and is often outdated.
Eurecom code has been contributed and was under OAI PL v1.0/v1.1.
For the cpack package contact: put generic email address that is
independent of an individual and that will remain reachable.
[1] https://www.doxygen.nl/manual/commands.html#cmdfile
- Extended fix to support multiple UEs instead of single UE
- Actions now trigger upon AMF reconnection
Per 3GPP TS 123 502 V16.7.0 (2021-01) Section 4.2.6 (AN Release):
When NG-AP signalling connection is lost due to (R)AN or AMF failure,
AN release is performed locally by AMF or (R)AN without relying on
signalling between (R)AN and AMF. This deactivates all UP connections.
PDU session related NGAP messages do not belong to NAS procedures lib.
* Create ngap_gNB_pdu_session_management.c and .h
* Move out ngap_gNB_pdusession_setup_resp, ngap_gNB_pdusession_modify_resp,
ngap_gNB_pdusession_release_resp from ngap_gNB_nas_procedures.c
* Move encode_ngap_pdusession_setup_response_transfer to ngap_common.c:
this transfer IE is common used both in PDU Session Management and
Initial Context Setup, so it's moved to the common lib
* Add ngap_gNB_pdu_session_management.c to CMakeLists.txt
This commit refactors the PDU Session Resource Modify Response message
structures to improve naming, documentation, and compliance with 3GPP TS 38.413 9.2.1.6.
Changes in NGAP:
- Rename qos_flow_tobe_modified_t to qos_flow_addmod_response_item_t to better
reflect its purpose as a QoS Flow Add or Modify Response Item IE (as per specs)
- Add mandatory AMF UE NGAP ID field to ngap_pdusession_modify_resp_t structure
- Optimize field types: change nb_of_pdusessions and nb_of_pdusessions_failed
from uint16_t to uint8_t (NGAP_MAX_PDU_SESSION limit) (ref 3GPP TS 38.413, 9.2.1.6)
- Update PDU Session Modify Response encoder to use amf_ue_ngap_id from the
message structure (pdusession_modify_resp_p->amf_ue_ngap_id) instead of
retrieving it from UE context (ue_context_p->amf_ue_ngap_id)
- Add comprehensive comments with 3GPP TS 38.413 section references throughout
Changes in RRC/NGAP:
- Populate amf_ue_ngap_id field in PDU Session Modify Response message from
UE context
- Update type reference to qos_flow_addmod_response_item_t
In the Initial Context Setup message, the NGAP forwards the AMF UE ID,
but not in the DL NAS Message, although 38.413 says, in $8.3.1.2 either
> The NG-RAN node shall use the AMF UE NGAP ID IE and RAN UE NGAP ID IE
> received in the INITIAL CONTEXT SETUP REQUEST message as identification
> of the logical connection
or in $8.6.2.2
> The NG-RAN node shall use the AMF UE NGAP ID IE and RAN UE NGAP ID IE
> received in the DOWNLINK NAS TRANSPORT message as identification of the
> logical connection
So forward in both cases for harmonization.
The PDUSessionResourceReleaseResponse message was missing the mandatory
pDUSessionResourceReleaseResponseTransfer IE in each released PDU session item. This caused Open5GS to send an error indication.
Changes:
- Add encode_ngap_pdusession_release_response_transfer() function to
properly encode the transfer structure (empty since Secondary RAT Usage
Information is optional and not used, per 9.3.4.21)
- Always include the mandatory PDUSessionResourceReleasedListRelRes IE
- Always encode the pDUSessionResourceReleaseResponseTransfer for each
PDU session item
- Fix Release Command handler to decode and log Cause from command transfer:
instead of incorrectly copying command data to response: the 2 transfer
IEs in the Command and the Response messages are different and should
not be mixed
- Split Command/Response struct type definitions
- Add missing includes
This commit is removing the storage of selected PLMN in NGAP UE context.
We store the Serving PLMN in the RRC UE context instead.
The Selected PLMN is the PLMN that the UE chose (or was directed to) for registration
and it is sent in the RRCSetupComplete. This is different from the selected
PLMN mentioned in the NG INITIAL UE MESSAGE for network sharing.
Selected PLMN: determines which core network and AMF the UE is registered with
GUAMI = Identifies the serving AMF and includes the PLMN of that AMF
Serving PLMN: the PLMN that is currently serving the UE (e.g. contained in GUAMI)
The AMF’s PLMN may match the selected PLMN, or not (especially in network sharing or roaming).
Regardless, the UE always have a Serving PLMN.
Initial UE message does not have a TAI IE per se, but TAI is a mandatory
member of the mandatory UserLocationInformation CHOICE.
NR CGI is also mandatory and carried inside UserLocationInformation:
in network sharing, the PLMN ID in TAI takes on additional
significance: RAN is shared but CN are different, so in this case PLMN in TAI is
needed for the AMF route the message to the correct operator’s core.
If network sharing applies (e.g., shared RAN between PLMN-A and PLMN-B):
the UE or network may select PLMN-B instead, and that PLMN identity
is included in the Initial UE Message’s TAI IE.
Conclusion:
1) UE always sends the selected PLMN during the registration,
regardless of whether it is shared or not.
2) Selected PLMN Identity is an actual IE sent in the RRCSetupComplete
while in NGAP there's no Selected PLMN Identity IE, only PLMN Identity
IEs in both TAI and NR CGI. It is a subtle difference.
3) The serving PLMN of the UE needs to be stored in RRC UE Context for
later use in NAS procedures. e.g. at initial registration it matches
the Selected PLMN
4) No need to store PLMN in NGAP UE Context, params are passed by RRC
5) TAI and NR CGI, which contain the PLMN identity, are mandatory in
UserLocationInformation IE CHOICE, and should reflect current status
Changes
- Initial UE Message: pass UE-selected PLMN and NR cell id from RRC to NGAP
- Uplink NAS Transport: use PLMN, TAC, and cell id provided by the message;
- Build NR CGI from gNB ID + cell id
- Store UE-selected PLMN only in RRC UE context at NAS_FIRST_REQ for later
Uplink NAS, stop storing PLMN in NGAP UE context
In the current memory management the caller wasn't responsible for freeing
memory they allocate. The ngap_gNB_encode_pdu function was taking ownership
of PDU contents by calling ASN_STRUCT_FREE_CONTENTS_ONLY, while callers
also expected to manage the same memory. This created unclear ownership semantics and
potential double-free bugs.
- Remove ASN_STRUCT_FREE_CONTENTS_ONLY from ngap_gNB_encode_pdu to prevent double-free
- Remove unnecessary ASN_STRUCT_FREE when encode function returns NULL
- Add proper ASN_STRUCT_FREE cleanup for heap-allocated PDUs in ngap_gNB.c functions
- Add ASN_STRUCT_FREE_CONTENTS_ONLY cleanup for stack-allocated PDUs in NAS and context management functions
- Ensure consistent memory cleanup patterns across all NGAP encoder callers
- Fix potential memory leaks in all ngap_gNB_encode_pdu call sites
This prevents double-free bugs and ensures proper cleanup of ASN.1 structures
in both heap and stack allocation scenarios.
* There is no IE corresponding to PDU sessions failed to release
in the PDU SESSION RESOURCE RELEASE RESPONSE message. This was removed
and the corresponding code was refactored and cleaned up.
* In the Release Command handler, only established PDU Session are set to be
released. The Response message is filled accordingly.
* Remove drb_is_active: function is unused and the logic will be later
added to another function to add DRBs if necessary
* Remove unused NGAP structs and empty TODO functions
* Remove unused pdusession_setup_req_t struct definition
Fix AMF selection fallback by PLMN ID when no UE identity is present or matching
If a mask is present (i.e., not zero), AMF selection by PLMN ID may
still fail, causing the AMF selection process to skip the fallback
option, i.e. selection by PLMN ID, when no UE identity is available or
when no match is found.
This MR adds also warnings in case there's a match for the AMF is not
found.
The mask could be present, .e.g not zero, but the selection of the AMF could
fail. This would lead to a skipping the selection of the AMF by PLMN ID,
which is the last option when no UE identity is present and/or matching.
this commit is refactoring the function ngap_gNB_handle_nas_first_req
to (1) fill first a local instance of ngap_gNB_ue_context_t and then
(2) pass it to ngap_store_ue_context which will allocate memory
for the instance to store in ngap
This function is needed also in upcoming NGAP
libraries (i.e. N2 Handover) and therefore is moved
to the NGAP utilities file. The function converts
transport_layer_addr_t data struct to BIT_STRING_t
by copying the content of its members. The naming
is also updated to tnl_to_bitstring.
selectedPLMN-Identity IE in RRCSetupComplete is an Index (long) of the PLMN selected
by the UE from the plmn-IdentityInfoList (SIB1) (see 3GPP TS 38.331)
while
Selected PLMN Identity in NGAP INITIAL UE MESSAGE Indicates the selected PLMN
id for the non-3GPP access (PLMN Identity ID carrying MNC, MCC and MNC size,
9.2.5.1 3GPP TS 38.413)
The legacy code was setting Selected PLMN Identity in the latter to an ID
value as the former, however in NGAP the IE to be encoded is PLMN Identity 9.3.3.5
therefore:
* set plmn type plmn_id_t in ngap_nas_first_req_t
* check whether received selectedPLMN-Identity is within bounds
* select PLMN from gNB_RrcConfigurationReq by selectedPLMN-Identity ID
note: this commit is assuming that the plmn-IdentityInfoList in SIB1
is matching the PLMN list in gNB_RrcConfigurationReq
* in NGAP: store the PLMN in the NGAP UE context, no need to fetch the PLMN
in the NGAP instance since the UE context already tells what PLMN
was selected
Closes#801
* use bitmask to select presence of either 5G-S-TMSI or GUAMI
* select the AMF based on
(1) absence of UE Identity (2) Presence of GUAMI (3) Presence of 5G-S-TMSI
Related to #801
* add function to process AMF Identifier
* add function to select AMF
* set const parameters in utility nnsf functions
* adopt utilities for memory allocation
* improve readability and maintainability
* improve logging
ngap_pdu_t has the same definition as byte_array_t, so it is
replaced by the latter. This simplify the stack and reduces
duplicated code.
Also, add function create_byte_array to copy from an
existing buffer to a new byte_array_t and replaced
allocCopy with create_byte_array, and adopted
OCTET_STRING_fromBuf whenever possible.
* new struct definition including both NGAP cause group and value
* add encoding function, temporarily in ngap_common.c
(in the long term to be place in a enc/dec NGAP library)
* extend Radio Network cause enum values
* add cause member to Setup Failure
NGAP Failure message - Initial Context Setup Failure.
When an Initial Context Setup Request is received with the UE context as null, it triggers Initial Context Setup failure.
We did not give a cause value, and therefore NGAP's "PDU sessions
failed" encoding failed. Give a cause value in all cases, so that this
cannot happen anymore.
To prevent against this, put an AssertFatal() into the encoder that
stops if an internally sent message does not have a correct cause value
(we can at least select a default).
Print an info message for all failed PDU sessions.
In rrc_gNB_send_NGAP_INITIAL_CONTEXT_SETUP_RESP(): if a PDU session is
already established, don't count it as failed.
