according to TS 38.331, RRCReconfiguration messages can be carried
in a container by different RRC messages, e.g. HandoverPreparationInformation,
HandoverCommand, RRCResume etc.. therefore before the introduction of new
RRCReconfiguration messages, e.g. for handover, a new design seems to be necessary
in order to improve modularity and maintainability of the code.
The goal of this commit is to make the generation of RRCReconfiguration
messages more modular by (1) preparing the RRCReconfiguration parameters
data in RRC (2) pass it to ASN1 for IEs allocation (3) encode to buffer
The following changes are introduced:
(1) introduce struct nr_rrc_reconfig_param_t to store the RRC parameters relevant
to encode the RRCReconfiguration IEs
(2) add RRC function get_RRCReconfiguration_params to fetch nr_rrc_reconfig_param_t
data from the UE context and
(3) pass it to the ASN1 encoder, e.g. do_RRCReconfiguration
(4) add a function build_RRCReconfiguration_IEs to allocate memory and build the
ASN1 NR_RRCReconfiguration_IEs_t and
(5) adopt it in do_RRCReconfiguration
(4) add free_RRCReconfiguration_params for memory management of nr_rrc_reconfig_param_t data
(6) add test for rrc_reconfiguration
get_RRCReconfiguration_params:
This function prepares RRCReconfigurationParams for RRC encoding.
Motivation of this change: depending on the RRCReconfiguration
message to be encoded, the ownership of ASN1 memory allocation
should belong to the ASN1 layer, therefore this function is
preparing the nr_rrc_reconfig_param_t data to pass to the
ASN1 encoder to build the ASN1 message and encode to buffer
The function is preparing the params for the IEs that are
either mandatory or shared among different RRC messages.
Specific fields that depend on the message to be encoded are then
added afterwards in the caller. The input param to indicate
re-establishment has been split between SRBs and DRBs, since
depending on the scenario the PDCP re-establishment can vary.
This will be addressed in a later commit.
This function is also handling xid.
build_RRCReconfiguration_IE:
The long term goal is to transfer ownership of memory allocation in ASN1 encoding to
build_RRCReconfiguration_IE, then by calling ASN_STRUCT_FREE_CONTENTS_ONLY
on dl_dcch_msg, all IEs allocated in the context are freed after encoding to buffer.
In the long term, createDRBlist, createSRBlist can also be brought into the context
of build_RRCReconfiguration_IEs and free the ASN1 structure after encoding.
This improves maintability and helps preventing memory leaks.
Currently, what is not allocated in the context, is nulled and freed outside.
free_RRCReconfiguration_params:
this function frees memory allocated to build the nr_rrc_reconfig_param_t data,
including the NR_DRB_ToAddModList_t and NR_SRB_ToAddModList_t. The function
freeDRBlist has been removed since no longer necessary.
dedicated_NAS_msg_list:
dedicated_NAS_msg_list handling has also been refactored, by:
(1) fetch the NAS PDUs from the UE context in get_RRCReconfiguration_params,
which translates to (2) passing an array of dedicatedNAS-MessageList + size
to the ASN1 encoding function where (3) the ASN1 encoding logic for the
dedicated_NAS_msg_list IE has been moved
Note, 3GPP TS 38.331:
dedicatedNAS-MessageList: SEQUENCE (SIZE(1..maxDRB)) OF DedicatedNAS-Message
* differentiate the 2 functions based on the input: either NR Cell ID or PCI
* enhanced variables naming to distinguish the parameters
* add logging for debugging purposes
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 count is used to size the dynamic array lcids_bj_pos. In case
count is zero, this would lead to runtime error. With this change,
the function will indicate to the caller that no SDUs are present and
will print an error.
According to 3GPP TS 38.331 5.3.5.5.2 (Reconfiguration with sync), the UE
shall consider the target SpCell to be one with a physical cell identity
indicated by the physCellId
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.
* Functions added:
decode_ngap_guami
decode_ngap_UEAggregateMaximumBitRate
decode_ngap_nssai
decode_ngap_security_capabilities
decode_ngap_mobility_restriction
* Adopt these functions in the common NGAP library
Integration: `2025.w23`
Closes#962, #956, and #801
See merge request oai/openairinterface5g!3464
* !3302 Enhance UE identity management in Initial UE Message and other NGAP improvements
* !3400 T bugfix: check input data a bit better
* !3459 Improvements in NR band tables according to Rel.17
* !3465 Fix checking that amf_ip_address section is not set.
* !3463 Move RRC radio parameters file to DU
* CI: Use host network mode in NSA-B200 pipeline
* !3389 Relax NR_UE_CAPABILITY_SLOT_RX_TO_TX asserts
* !3417 Imscope updates
* !3443 Fix data race in NR UE MSG3 scheduling
* !3467 remove dead globals
Fix data race in NR UE MSG3 scheduling
Fixed a data race between DL processing of RAR and UL scheduler, which might
result in dropping MSG3.
It was possible that the UL scheduler for the UL slot which RAR indicates as
MSG3 slot was already run by the time the RAR was decoded.
Therefore when DCI for RAR is decoded, assume worst case and halt UL scheduler
for next slot until RAR is decoded solving the data race. This also in turn
halts all later scheduling due to sequential nature of the UL scheduler calls.
Closes#962
imscope updates
- Add CSV export button to imscope
- Add extra cache for IQ data in imscope record thread so that UE time domain
data can be kept until PDSCH is decoded.
- Add metadata to UE time domain samples scope
- Add UE pdsch pre-compensation IQ and PDSCH channel estimates
Move RRC radio parameters file to DU
A number of radio-related RRC parameters, e.g., CellGroupConfig, "originate" at
the DU and are sent to the CU for forwarding to the UE only. Similarly, there
are additional parameters, e.g., RLC-BearerConfig (part of CellGroupConfig),
that originate at the DU.
Hence, the DU decides about these parameters, depending on the MAC state and
capabilities. To clarify this, move the existing
openair2/RRC/NR/nr_rrc_config.{c,h} => openair2/LAYER2/NR_MAC_gNB/nr_radio_config.{c,h}
So that developers know that while those are RRC parameters, they originate at
the DU.
In other words, the CU/RRC is not supposed to use any of these functions in
the RRC. Correspondingly, includes of this file have been cleaned up (and when
they are not necessary at the MAC as well)
Fixed a data race between DL processing of RAR and UL scheduler, which
might result in dropping MSG3.
It was possible that the UL scheduler for the UL slot which RAR
indicates as MSG3 slot was already run by the time the RAR was decoded.
Therefore when DCI for RAR is decoded, assume worst case and halt the
earliest corresponding UL scheduler call until RAR is decoded solving
the data race. This also in turn halts all later scheduling due to
sequential nature of the UL scheduler calls.
Following a power cycle of the CI machines in the NSA-B200 setup, the gNB
machine encountered a networking issue. Although packets were observed leaving
and returning to the host of gNB, they failed to reach the container.
Debugging steps taken:
- upgraded the gNB machine
- reinstalled Docker
- reviewed and verified IP rules and routing settings
Setting the container to use host network mode resolved the issue.
Enhance UE identity management in Initial UE Message and other NGAP improvements
This MR improves the Initial UE Message procedures by supporting simultaneous
presence of both 5G-S-TMSI and GUAMI. Previously, only one identity could be
used, leading to potential AMF selection failures. Now the presenceMask allows
both identities. The AMF selection is prioritizing GUAMI first, then falling
back to 5G-S-TMSI, and finally using PLMN or highest capacity.
Also, fix handling of selected PLMN identity in NGAP.
Refactoring:
- Select the AMF based on (1) absence of UE Identity (2) Presence of GUAMI
(3) Presence of 5G-S-TMSI
- Also refactored the AMF selection logic for better readability and reliability.
- Refactor and cleanup rrc_gNB_send_NGAP_NAS_FIRST_REQ
- Replace ngap_pdu_t with byte_array_t
- Add guami_t to ngran_types.h: refactor NGAP and RRC code to use one common
GUAMI type instead of two identical ones
Also:
- Bugfix in ngap_gNB_handle_ng_setup_response: use correct count for PLMNSupportList
Closes issue #801
A number of radio-related RRC parameters, e.g., CellGroupConfig,
"originate" at the DU and are sent to the CU for forwarding to the UE
only. Similarly, there are additional parameters, e.g., RLC-BearerConfig
(part of CellGroupConfig), that originate at the DU.
Hence, the DU decides about these parameters, depending on the MAC state
and capabilities. To clarify this, move the existing
openair2/RRC/NR/nr_rrc_config.{c,h} => openair2/LAYER2/NR_MAC_gNB/nr_radio_config.{c,h}
So that developers know that while those are RRC parameters, they
originate at the DU.
In other words, the CU/RRC is not supposed to use any of these functions
in the RRC. Correspondingly, includes of this file have been cleaned up
(and when they are not necessary at the MAC as well).
One of the next commits moves nr_rrc_config.c "down to" the MAC/DU. The
BearerConfig functions are only used at the DU, so move them here in the
corresponding file.
When data is generated by "normal" T tracers, it should be fine.
But it might come from unknown sources and then content might be
"strange". So let's validate input data a bit more.
The way allocation is done (granularity of 64KiB) makes a crash more
difficult to achieve, but if a trace is exactly 64KiB, we miss 4 bytes
in the realloc and then anything may happen.
Integration: `2025.w22`
Closes#832
See merge request oai/openairinterface5g!3452
* !3415 several fixes and cleanup for nrLDPC_coding_t2
* !3448 T: macpdu2wireshark: dump to file instead of sending UDP packets
* !3449 bugfix: pass correct buffer
* !3453 CI: revert modification of SSB per RACH occasion in SC-FDMA test
* !3440 Update NAS documentation
* !3451 fix the number of preambles per SSB at UE in case PRACH is configured with groupB
* !3441 Replace hashtable with epoll_event_t in rfsimulator
* !3277 Add CI test to force RRC IDLE and new connection setup with 5G-S-TMSI
* !3454 Keep old MAC stats after re-establishment
* !3450 Make number of UL/DL actors in NR UE fully configurable
* !3458 (doc): update README with build icons for dedicated arch and os
Make number of UL/DL actors in NR UE fully configurable
Due to different processing requirements on different CPUs it might be
beneficial to enable the users to set the number of UL/DL actors.
Allow disabling UL/DL actor frameworks and processing inline or setting
the number of DL/UL threads with --num-ul-actors/num-dl-actors
This was tested to work with 0 UL/DL actors with rfsim.
GUAMI fields (Set ID, Pointer and Region ID) were decoded as Octet String,
however they are encoded as BIT STRING. Therefore, the GUAMI value was wrongly decoded.
In the AMF logs the AMF IDs are 1,1,1, however in gNB logs we had 1,64,4
Quick local test confirmed that:
---- TESTING AMF IDs = 1 ----
Region ID (OCTET STRING): 1
Region ID (BIT STRING): 1
Set ID (OCTET STRING): 64
Set ID (BIT STRING): 1
Pointer (OCTET STRING): 4
Pointer (BIT STRING): 1
The difference arises because:
- OCTET STRING treats the buffer as raw bytes, with all bits used.
- BIT STRING includes a `bits_unused` field, which tells how many padding bits
are present in the least significant end. This is especially important in
3GPP ASN.1 definitions like AMF Set ID (10 bits), AMF Region ID (8 bits),
AMF Pointer (6 bits), where the full byte(s) may contain unused bits that
must be masked out.
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
Guido Casati