Similarly to the commit "Use F1 UE context setup/modif Request in
stack", we do both UE context setup/modification response at once
because of some functions that are shared by the MAC message handler.
Use the new, tested F1 UE context setup request and modification
requests in the stack.
We have to do both at once, because there are some functions that are
used by handlers for both messages, notably
- handle_ue_context_drbs_setup()
- handle_ue_context_srbs_setup()
(+ and some functions called by those two). For instance, the first uses
the (new/old) type f1ap_drb_to_be_setup_t/f1ap_drb_to_setup_t which is
shared. The alternative would be to duplicate the functionality
temporarily, and I want to avoid unnecessary code churn.
Reintroduce separate message types to simplify the encoding/decoding,
including shorter names. The old types will be removed once everything
has been migrated to the new encoder/decoder, which should ensure that
everything is properly migrated to the unit-tested encoder/decoders.
Also, for each type of F1 message (F1 UE context setup request,
response, modification request, ...) introduce a separate type to avoid
to mistakenly use wrong fields, which can lead to bugs. In this regard,
the DL PDCP SN bit size in the DRB-ToBeSetup list of the UE context
setup request is optional, as it will also be used in the UE context
modification request DRB SetupMod list (which avoids quite some code
duplication). The encoder checks that this IE is present, though.
F1AP_LIB_FIND_IE() is used to look up elements in a list, but was
hitherto hardcoded to use "protocolIEs" as an intermediate struct. A
follow-up commit will use this macro where we don't have protocolIEs,
but "iE_Extensions". Hence, modify to make it work for that case (and
others) as well.
Introduce generic _F1_CHECK_EXP(), which is like the macros for checking
values (_F1_EQ_CHECK_INT() etc). Reuse the same for introducing
_F1_EQ_CHECK_OPTIONAL_IE that will be used to write the check for
optional fields more concisely.
CP_OPT_BYTE_ARRAY() FREE_OPT_BYTE_ARRAY() are macros to wrap handling of
optional byte arrays.
_F1_MALLOC() simplifies allocations and is similar to asn1cCallocOne(),
but provided to avoid confusion (since more than ASN.1 structures will
use it).
All will be used in the following commits.
Signal gNB-DU config update CellStatus from DU to CU
Add the cell status to gNB-DU configuration update message, including
test. Use the gNB-DU configuration update to signal the cell status in
the stack.
This IE was not included in a previous refactoring round, but is at
least necessary to be decoded when interoperating with the OSC O-DU.
This is preparatory work to allow NSA-like modes to be used over F1 in
the future. Notably, it fills the F1 message for UE context setup with
GTP TEID, and fills additional information to "make the F1 encoder
happy" (fill in QFI etc). Also, provide some F1 fixes to make this work.
Remove stale UE connections, if relevant.
Issue 947 and compilation improvements
This MR started with a small commit (03c7f151) to close#947. Little did
I know that I would be taken in a long journey through OAI compilation
hell.
- encode all SI containers the encoding function gets (it's not the
encoding function's job to enforce semantics)
-
Fixes: 30628b820c ("Add encoding/decoding lib for F1AP Setup Response
(Interface Management)")
Encapsulate the asn1c call from cmake in a cmake function run_asn1c().
As a notable change to the previous manual add_custom_command()
invocation, in suppresses the output of asn1c by default [1] and stores
it in a log file. In case of asn1c4 error, the output will output on
stdout.
Use the new run_asn1c() in all occasions for code generation.
[1] it is quite verbose, with many warnings that we cannot influence nor
suppress, and lists all generated files which is verified by the build
system automatically, anyway.
[E2 agent] RAN Control SM - support for REPORT Style 1 ("RRC Message" and "UE ID" RAN Parameter IDs)
[Spring of Code 2024] contributions
Extended the RAN Control Service Model at E2 Agent to support all RC
REPORT Styles (1 - 5)
Implemented the following RAN Parameter IDs for REPORT Style 1:
1. "RRC Message": any DL-DCCH, and any UL-DCCH
2. "UE ID": as per spec, when the RRC Setup Complete or F1 UE Context
Setup Request detected
As per spec, UE ID shall be reported when the message event configured by
the Event Trigger Style 1 is set to “RRC Setup Complete" message (UE attach), or
“Xn/NG Handover Request” or “F1 UE Context Setup Request” (Intra gNB Handover).
In OAI RAN, Xn/NG Handover is not yet supported, and therefore not added as the trigger event
in this commit.
Additionally, as the Event Trigger Definition Format 1 is common for both "RRC Message" and "UE ID",
E2 node will report the “RRC Setup Complete" message which the xApp will decode and print.
Co-authored-by: Khanh Toan Pham <khanh.toan.pham@hhi.fraunhofer.de>
Co-authored-by: Shrinish Donde <shrinish.donde@hhi.fraunhofer.de>
Co-authored-by: Theodoros Tsourdinis <theodoros.tsourdinis@sorbonne-universite.fr>
Co-authored-by: Miguel Fuentes <miguel.fuentes@i2cat.net>
Co-authored-by: Teodora Vladic <teodora.vladic@openairinterface.org>
During refactoring, the previously implemented NSSAI field of the cell
info structure was not written to F1AP ASN.1 structures anymore;
eq_f1ap_cell_info() also conveniently omitted the corresponding equality
check. Add this back so the CU can correctly receive the NSSAI in case
of F1 split operation.
Fixes: f278b00837 ("Add encoding/decoding library for F1AP Setup
Request (Interface Management) ")
F1AP IDs: Add update, fix concurrency bug
I suspect a concurrency bug: For instance, during reestablishment, the
CU needs to update the DU UE ID under which the UE is identified in the
DU. Previously, the CU would remove, then add the DU UE ID info. At the
same time, the PDCP thread might look up the information. This can lead
to asserts. Modify the code to do the update under (one) lock.
Also, refactor some code.
Introduce function cu_update_f1_ue_data() which does remove+add under
one lock. This fixes a concurrency bug. For instance, during
reestablishment, the CU needs to update the DU UE ID under which the UE
is identified in the DU. Previously, the CU would remove, then add the
DU UE ID info. At the same time, the PDCP thread might look up the
information. This can lead to asserts. Use the above addmod
functionality to do the remove-add under a mutex.
Modify test to verify this works as expected.
- Refactor SCTP Association Response Handling
- Unified function for both CU-CP and CU-UP handling
- CU-CP: Notifies RRC of E1 connection loss with CU-UP
- CU-UP: Initiates a new SCTP association request to regain E1 connection
- this fix will prevent issue #878 from happening
- Send list of PDU Session Resources to Failed Setup in the (PDU Session
Resource/Initial Context) Setup Response
- depending on different failure scenarios
- e.g. (#878) when No CU-UP is associated and still the CU-CP receives a PDU
Session Setup Request
- add relevant functions to handle NGAP Setup Response messages with failed
list of items
- this is an extra failure handling to make #878 is handled if it ever happens
again
- NGAP Cause Refactoring
- Refactor struct for NGAP cause group and value
- Add extended radio network cause enumeration values
- Refactor redundant code into a new NGAP cause encoding function
- Minor logging, function descriptions improvements
Closes#878
Modify xu_add_f1_ue_data() to be xu_addmod_f1_ue_data(), i.e., "addmod"
behavior in which it is possible to also update f1_ue_data. I do it this
way since an xu_updade_f1_ue_data() function would be almost the same as
the add function (only deleting existing data, whereas the original
add() was asserting in that case).
Modify tests to test for this behavior.
This fixes a concurrency bug. For instance, during reestablishment, the
CU needs to update the DU UE ID under which the UE is identified in the
DU. Previously, the CU would remove, then add the DU UE ID info.
At the same time, the PDCP thread might look up the information. This
can lead to asserts. Use the above addmod functionality to do the
remove-add under a mutex.
* this function is used by both CU-CP and CU-UP
* it behaves differently depending on the type of E1 instance:
CU-CP: inform RRC of E1 connection loss with CU-UP
CU-UP: trigger a new SCTP association request by sending an ITTI to the CU-UP task
* after receiving the E1AP register request, the CU-UP will send a new association request to
SCTP until new E1 connection is achieved by sending a TIMER_HAS_EXPIRED message to the CU-UP
task. The function e1apHandleTimer() is basically triggering a new E1 association request
until new E1 connection is achieved
* print SCTP association state in e1ap.c whenever needed
Related to #878
Robert Schmidt