Per TS 33.501 6.9.2.3.4 and Fig 6.9.2.1.1-1, when sending
RRCReestablishment with nextHopChainingCount, the gNB is staying at
the same NCC level (not advancing). Therefore, horizontal derivation
from the currently active KgNB must be used, not vertical derivation
from NH.
Vertical derivation (from NH) is only used when advancing to a new
NCC level, which happens during handover or masterKeyUpdate procedures.
The previous implementation incorrectly used vertical derivation from
NH whenever nh_ncc > 0, which caused key mismatch between gNB and UE
during reestablishment after handover, leading to integrity check
failures.
This fix ensures both gNB and UE use horizontal derivation when
nextHopChainingCount matches the current NCC level, aligning with the
specification's "virtual NH at NCC=0" model where:
- Horizontal derivation = derive KNG-RAN* from currently active KgNB
- Vertical derivation = derive KNG-RAN* from NH (only when advancing NCC)
During N2 handover, the UE receives reconfigurationWithSync which correctly
sets the target cell frequency in mac->phy_config.config_req.carrier_config
via config_common_ue() call.
However, when SIB1 is decoded after reconfiguration,
nr_rrc_mac_config_req_sib1() calls config_common_ue_sa() which unconditionally
overwrites the frequency with the command-line parameter (downlink_frequency),
which corresponds to the source cell frequency.
This causes a critical issue during RRC re-establishment:
- The UE uses the wrong frequency (source cell) for key derivation (kgnb*)
- The gNB uses the correct frequency (target cell) for key derivation
- This mismatch results in different kgnb* keys on UE and gNB
- Integrity check fails: "Integrity of RRCReestablishment failed, going to IDLE"
Root cause:
config_common_ue_sa() is used for SIB1 processing (initial cell selection) and
uses ServingCellConfigCommonSIB which doesn't contain absoluteFrequencyPointA.
It must derive frequency from command-line parameters. However, after handover,
the frequency has already been correctly set by config_common_ue() (used for
reconfigurationWithSync) which uses ServingCellConfigCommon with absolute
frequency information.
Solution:
Modify config_common_ue_sa() to preserve the existing frequency if it's already
initialized (non-zero). Only set frequency from command-line parameters during
initial cell selection when dl_frequency is 0. This ensures:
- Initial cell selection: frequency derived from command-line parameter, just once
- After handover: frequency preserved from reconfigurationWithSync
- MAC maintains its own frequency state independently
The fix applies to both DL and UL frequencies to maintain consistency.
There is probably room for more refactoring to the resync flow, since
the functionalities in config_common_ue and config_common_ue_sa are
partially overlapping and upon reconfigurationWithSync some other
configurations might be applied twice.
These logs are very helpful to identify cell configuration
changes in MAC/PHY, for monitoring purposes, and to rapidly
signal integrity failures during re-establishment.
The RNTI from the target context was not updated after HO acknowledge
this led to a failure in the first re-establishment after HO.
This commit is introducing the function nr_rrc_apply_target_context
in nr_rrc_n2_ho_acknowledge() and also updates the cell ID for
consistency.
Refactor handover target context application logic into a reusable
function nr_rrc_apply_target_context() that updates both F1AP
associations (secondary UE and DU association) and RNTI from the
target handover context.
And apply to rrc_CU_process_ue_context_modification_response()
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
1) Remove UE Context Release Response code: there is no
such thing in the specs, it is either UE Context Release Request
(NG-RAN node initiated) or UE Context Release (AMF initiated)
(3GPP TS 38.413). The former message has only the request, no
response is defined by the specs. The code in the stack had no
purpose at all and was removed.
2) The UE Context Release Request message only contains a PDU
Session Resource List (optional) of PDU Session IDs, therefore
the use of pdusession_release_t was wrong and was refactored
Problem:
During N2 handover with integrity protection (NIA1/NIA2), the target gNB
was disabling ciphering when configuring SRB1 security, while the UE
continued using the old security context from the source gNB until it
received and processed the RRC Reconfiguration with masterKeyUpdate. The
first PDUs sent after CFRA were still ciphered with the old keys, but the
target gNB had ciphering disabled, causing it to skip deciphering and
attempt integrity verification on ciphered data, leading to MAC-I
mismatches and integrity failures.
Specification Reference:
According to TS 33.501 section 6.11, "the UE shall keep the K gNB used in
the source cell until the handover or a connection re-establishment has been
completed successfully". This means the UE continues using the old security
context (old KRRCint, KRRCenc) until it receives and processes the RRC
Reconfiguration with masterKeyUpdate. The target gNB must therefore enable
ciphering during handover setup to correctly decipher and verify integrity
of PDUs sent with the old security context before the UE switches to the new
keys.
Root Cause:
The code was calling nr_rrc_pdcp_config_security(UE, false) during
handover setup, which disabled ciphering. This was incorrect because:
1. The UE already has security active from the source gNB
2. The UE continues using old ciphered keys until masterKeyUpdate
3. The UE sends ciphered PDUs immediately after CFRA succeeds
4. The target gNB must be able to decipher these PDUs to verify integrity
Why it only manifested when drb_integrity = "yes":
The bug was always present, but only caused visible failures when
integrity verification was enabled. When drb_integrity = "no", the config
typically also sets integrity_algorithms to only NIA0, resulting in
UE->integrity_algorithm = 0, which causes has_integrity = 0 for SRB1,
skipping integrity verification and hiding the underlying ciphering bug.
When drb_integrity = "yes", integrity_algorithms typically includes
NIA1/NIA2, resulting in has_integrity = 1 for SRB1, causing integrity
checks to run on ciphered data and fail.
Fix:
Change nr_rrc_pdcp_config_security(UE, false) to
nr_rrc_pdcp_config_security(UE, true) during handover setup to enable
ciphering immediately, allowing the target gNB to correctly decipher and
verify integrity of PDUs sent with the old security context.
Note: This fix is specific to handover. During initial context setup,
ciphering should remain disabled until SecurityModeComplete is received,
as the UE hasn't activated ciphering yet at that point.
During re-establishment, new KgNB* is derived, requiring new UP keys (KUPint,
KUPenc) to be sent to CU-UP. When do_drb_integrity = true, CU-UP needs the
updated integrity keys to verify DRB PDUs. Without this update, CU-UP uses
old keys while the UE uses new keys, causing integrity failures.
The fix ensures security info is always sent during re-establishment,
which is critical for DRB integrity.
- Add delayed_action_state_t in the UE context for ongoing delayed action
- Move delay check and timer re-enqueue to rrc thread in rrc_gNB.c (rrc_delay_transaction)
- Call delay before NGAP setup/release handlers; remove local delay logic from rrc_gNB_NGAP.c
- Clear on RRCReconfigurationComplete (reset_delayed_action)
Closes#960
- Enable telnet server on VNF (gNB) and UE in docker-compose.yaml
- Add new test cases for PDU session management:
* Add PDU session via UE telnet
* Release PDU session via telnet
* Verify connectivity after PDU session release
- Integrate telnet commands into existing container_5g_rfsim_u0_25prb.xml pipeline
- Test cases added before undeploy step in proper execution order
This commit introduces a new telnet server command `pdu_session_release` to
manually trigger the NGAP PDU Session Release Command message from the telnet ci shell.
This is useful for integration testing of PDU session teardown behavior.
Details:
- Added `trigger_ngap_pdu_session_release()` to send NGAP_PDUSESSION_RELEASE_COMMAND
to the RRC task, targeting the specified `gNB_ue_ngap_id`.
- The command currently releases PDU session ID 10 (hardcoded).
- Hooked into telnet shell with command: `pdu_session_release [gNB_ue_ngap_id]`
Usage example:
telnet > pdu_session_release 1
We need to keep PDU sessions and DRBs in list until the NGAP PDU Session Release Response is sent.
* Introduced find_drb() and remove_drbs_by_pdu_session() helpers to locate
and clean up DRBs linked to a specific PDU session
* Targeted per-session DRB removal in rrc_gNB_send_NGAP_PDUSESSION_RELEASE_RESPONSE()
* Ensures DRBs for unaffected PDU sessions remain intact
* Remove unused PDU_SESSION_STATUS_RELEASED status: keeping this status is no longer relevant
since the PDU sessions are effectively removed from the RRC lists
Closes#867
Also, refactor rrc_gNB_process_NGAP_PDUSESSION_RELEASE_COMMAND
3GPP TS 38.413 8.2.2 PDU Session Resource Release says:
> upon reception the NG-RAN node shall execute the release of the requested PDU sessions.
> For each PDU session to be released the NG-RAN node shall release the corresponding
> resources over Uu and over NG, if any.
Therefore, any PDU session in the pdusession_release_params list that is
also present in the RRC list can be set to release, regardless of its status.
The function signature was also updated along with other minor changes.
The partial-tunnel deletion API was buggy and redundant:
* e.g. It erased entries from globGtp.te2ue_mapping but never erases
the corresponding entries from inst->ue2te_mapping[ue].bearers
All current use cases are already covered by:
* newGtpuDeleteOneTunnel() for targeted deletion
* newGtpuDeleteAllTunnels() for full cleanup
Call sites should explicitly loop over newGtpuDeleteOneTunnel()
if multiple tunnels need removal.
This commit implements proper PDU Session Release handling across
RRC, PDCP, F1AP, E1AP to ensure clean resource cleanup when
a PDU session is terminated.
Key changes:
NGAP:
In `rrc_gNB_process_NGAP_PDUSESSION_RELEASE_COMMAND()`:
* Populates E1AP Bearer Modification for each released session
* If a CU-UP is connected, triggers `bearer_context_mod()` for PDU teardown
PDCP:
* Added `nr_pdcp_release_drbs()` to remove all DRBs linked to a given PDU session
* Called from `e1_bearer_context_modif()` for correct clean-up during session release
F1AP UE Context Modification:
Replace direct RRC message transfer with F1AP UE Context Modification Request
to properly handle PDU session release according to 3GPP TS 38.331.
3GPP TS 38.331 `5.3.5.6.4 DRB release` says: whether or not the RLC and MAC entities associated
with a PDCP entity are reset or released is determined by the CellGroupConfig. Thus,
updated CellGroupConfig needs to be received by the UE. This has to be retrieved by CUCP
from the DU. Therefore:
After receiving an NGAP_PDUSESSION_RELEASE_COMMAND, the CUCP shall:
1) forward (store for later) the NAS PDU to the UE, if present as per 3GPP TS 38.413, and
2) send a UE Context Modification to the DU with the list of DRBs to release
and the RRC container (RRCReconfiguration with NAS PDU)
After reception of UE Context Modification Response, the list of drbs to release
is prepared based on PDU session status PDU_SESSION_STATUS_TORELEASE
in rrc_gNB_generate_dedicatedRRCReconfiguration and then encoded
in drb_ToReleaseList for a new RRCReconfiguration with the new cellGroupConfig.
Key changes:
* rrc_gNB_generate_dedicatedRRCReconfiguration_release() now uses F1AP UE Context
Modification Request instead of direct RRC transfer
* Only DRBs to be released are now added to the list.
* The ASN.1 memory allocation is entirely done in build_RRCReconfiguration_IEs
* No longer needed to store ASN1 struct in UE context
GTP-U:
* Previous implementation had incomplete tunnel cleanup during PDU session release
- Missing distinction between N3 (PDU session level) and F1-U (DRB level) tunnels
- Lack of proper DRB identification for F1-U tunnel deletion
Major Changes:
* GTP tunnel teardown now handled in `e1_bearer_context_modif()` using the correct
F1 or N3 GTP instance (`newGtpuDeleteOneTunnel()`)
* Enhanced Tunnel Deletion Logic (cucp_cuup_handler.c):
- Separate handling for N3 tunnels (1 per PDU session) and F1-U tunnels (1 per DRB)
- Added proper DRB identification for F1-U tunnel cleanup
- Improved error handling with detailed logging for each tunnel deletion
- Enhanced logging to distinguish between N3 and F1-U tunnel operations
* New PDCP API Function (nr_pdcp_oai_api.c/h):
- Added nr_pdcp_get_drb_ids_for_pdusession() function
- Enables retrieval of all DRB IDs associated with a specific PDU session
- Supports proper F1-U tunnel cleanup by providing DRB identifiers in CUUP
* Enhanced GTP Interface (gtp_itf.cpp/h):
- Modified newGtpuDeleteOneTunnel() to accept tunnel_type parameter
- Improved logging to distinguish between PDU session and DRB tunnel types
- Better error messages for tunnel deletion failures
- Enhanced debugging information for remaining tunnels
Clean-up:
* Ensured xid tracking works consistently between PDU Session Establishment (with NAS PDU)
and dedicated RRCReconfiguration
* Add function to release GTP-U tunnel in Bearer Context Modification Request handler
* Do not send rrc_gNB_send_NGAP_PDUSESSION_RELEASE_RESPONSE when no PDU session are to
be released: it is sent upon completion of the RRCReconfiguration and needs to contain
released PDU Sessions (mandatory IE), therefore it is no necessary to send it in case
there is no PDU session to release.
Related to #867
Co-authored-by: rmagueta <rmagueta@allbesmart.pt>
Problem:
- GTP-U logs showed negative TEID values (e.g., -1943516315) due to signed/unsigned
conversion. Due to wrong conversion from uint32_t to int and overflow caused negative values.
- TEID values were inconsistently formatted across different log statements, due to
mixed use of %d, %u, %x formats for TEID logging. Made debugging and troubleshooting difficult
Changes:
1. Fixed signed/unsigned conversion bug: use teid_t. Prevents overflow when TEID values exceed int range.
2. Standardized TEID logging format: all TEID values now use '0x%x' hexadecimal format.
Consistent 'TEID' capitalization throughout
According to TS 38.463 - clause 9.2.2.4 and 9.3.3.12.
Also, fix response message by encoding choice IE only
with presence of modified PDU sessions.
Co-authored-by: rmagueta <rmagueta@allbesmart.pt>
!3519 refactored the SDAP to use the QFI from the header rather
than pass it to the rx function and got rid of the initialization
of QFI to -1.
However, entity roles are stored into the drb2qfi table, and the
indexing implies that the QFI is known. While in TX it is not an
issue since packets are forwarded based on the QFI, in RX the QFI
can only be parsed from the heaedr, therefore if headers are
disabled (--enable_sdap) the QFI is not there and it is wrong to
access the header (`buf[0]`) and looking for it.
This commit adds `enable_sdap` to `nr_sdap_entity_t` and initialize
it in `nr_sdap_add_entity()` from `sdap->role`
(disabled when `NO_SDAP_HEADER`). In `nr_sdap_rx_entity()`, only
parse `buf[0]` for QFI and derive `sdap_ul_rx`/`sdap_dl_rx` when
`enable_sdap` is true; otherwise, keep `offset=0` and forward
payload unchanged.
This commit refactors the SDAP entity QoS flow to DRB mapping functionality
to improve code organization and enhance maintainability.
Key changes:
- Split nr_sdap_qfi2drb_map_update into focused functions:
* nr_sdap_add_qos_flows_to_drb: handles QFI addition to DRB
* nr_sdap_rm_qos_flows_from_drb: handles QFI removal from DRB
* nr_sdap_ue_control_pdu_config: handles UE control PDU generation
- Consolidate add/modify logic into reusable nr_sdap_addmod_entity function
- Remove entity existence checking and updating from new_nr_sdap_entity:
this function should only add SDAP entities
- Improve function separation of concerns: do SDAP entity add or update
separately and improve modularity by splitting operations in self
contained functions
- At SDAP creation, do only add of QFI to DRB mapping
- rename new_nr_sdap_entity to nr_sdap_add_entity for function naming consinstency
- Remove rb_id parameter from nr_sdap_tx_entity() function signature
- Update tx_entity function pointer
- Remove rb_id parameter from sdap_data_req() function signature
- Remove unused rb_id variable from sdap_tun_read_thread
The rb_id parameter was redundant since SDAP determines DRB ID
from QFI mapping via entity->qfi2drb_map(entity, qfi). This
simplifies the interface.
Each QFI should always be mapped to a DRB. If that is not the case, we
have an undefined behavior. This should not occur. This commit prints
an error in tx_entity and returns.
The TX/RX entity should have different behavior according to
5.2.1, 5.2.2, 3GPP TS 37.324, depending on whether it is UL and DL.
The gNB can play a role both as UL RX entity and DL TX entity, while
the UE can play a role both as UL TX entity and DL RX entity.
The goal of this commit is to extend the information stored in the
SDAP entity as the current code is just marking the entity as TX/RX.
The commit introduces a bitmap to store the role of the
entity, which can be DL RX, DL TX, UL RX and UL TX. Based on this
the TX SDAP entity knows whether a DL/UL PDU should be build, and
the RX SDAP entity knows whether a DL/UL PDU should be processed.
See also Figure 4.2.2-1.
SDAP headers are present only if enable_sdap option is used.
nr_sdap_qfi2drb_map_update function pointer should
process QFIs to add and release from the entity mapping, therefore
a new function pointer for QFIs to add was introduced and
the function pointer to release the QFIs was called in the same function.
Now the nr_sdap_qfi2drb_map_update is:
(1) looping through the QFIs to add/update and store in the qfi2drb_table
(2) looping through the QFIs to release and delete from qfi2drb_table
Also:
* Update the function signature to use sdap_config_t and nr_sdap_entity_t
* log error when the update fails
* limit the scope of the function
* clang-formatted
* removed limit on table entries set by AVLBL_DRB, replaced with MAX_DRBS_PER_UE
The function nr_sdap_ue_qfi2drb_config should do UL QoS flow to DRB mapping configuration
for a SDAP entity has already been established according to TS 37.324, 5.3 QoS flow to
DRB Mapping, 5.3.1 Configuration Procedures. It should handle both mapping rules to add and to remove.
To this purpose:
* Simplify function signature by passing the sdap config.
* Improve readability of the function.
* Move handling of sdap.mappedQFIs2ReleaseCount (in nr_reconfigure_sdap_entity)
inside the function.
* Simplify end-marker control PDU mapping function by removing unused
DRB ID input parameter (the function is fetching the DRB ID based on the input
map type)
* use int instead of legacy rb_id_t
* limit scope of functions whenever necessary
The goal of this function is to return the DRB ID mapped to the input QFI, for both DL and UL.
The function looks up the DRB that is mapped to the QFI, if no mapping rule exists
returns the default DRB. Returns 0 If no mapping and no default DRB exists for that QFI
The function should not update the stored mapping rules, that is done when receiving
a new SDAP configuration. In this function it was removed.
See TS 37.324, 5.2.1 Uplink
> If there is no stored QoS flow to DRB mapping rule for the QoS flow as specified in the subclause 5.3,
> map the SDAP SDU to the default DRB else, map the SDAP SDU to the DRB according to the stored QoS flow to DRB mapping rule.
* change function signature: pass the sdap_config_t
* update qfi2drb mapping when receiving a configuration for an already existing SDAP entity
* always update mapping rules, not only for default DRB
* use get_sdap_Config to process sdap_Config
* move SDAP config logic to the scope where it is relevant
* add SDAP entity direcly in RRC, not from PDCP
* replaced nr_pdcp_add_drbs with single add_drb call: it was no longer
efficient to keep it in the new logic. The addMod list can be looped directly in RRC.
* add specific function to add bearers from addMod list in E1, NSA, and UE
Prevent assertion in ngap_gNB_nas_uplink() due to uninitialized selected_plmn_identity:
the selected_plmn_identity field was not being set during N2 handover,
causing the assertion ((plmn->mnc_digit_length == 3) || (plmn->mnc_digit_length == 2))
to fail when processing subsequent NAS messages. The issue is that the Serving PLMN
is not stored by RRC. During N2 mobility, RRC can get this info from GUAMI.
When receiving the Handover Request the target gNB knows from GUAMI
which serving PLMN is the AMF belonging to. In current design, allowed PLMNs
are stored in rrc.configuration. The incoming PLMN needs to be validate
against the PLMNs in the list, then stored in the UE context as Serving PLMN.
This change adds PLMN validation when processing handover requests from the source gNB.
The validation is needed because:
- Target gNB must verify that the PLMN from the GUAMI in the handover request
is allowed by its configuration before accepting the handover to prevent handover
to unsupported PLMNs.
- When PLMN validation fails, the target gNB now properly sends NGAP_HANDOVER_FAILURE
- UE Context must store serving PLMN for later use
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
- Add XML pipeline for N2 handover testing
- Add Docker compose for two monolithic gNBs
- Features:
* Two monolithic gNBs (gNB1, gNB2) with proper CU+DU parameters
* Gradual attenuation control using RC4DAT attenuator (5s duration)
* N2 handover sequence: gNB1 → gNB2 → gNB1
* Proper channel mapping: ch1-2 for gNB1, ch3-4 for gNB2
* Telnet server configuration for CI commands
* Handover-specific neighbor configuration
* Clean test state management with attenuator reset
- Add band mismatch check in valid_du_in_neighbour_configs function
- Ensures neighbor cell band matches serving cell band
- Prevents invalid neighbor configurations for handover
- Trigger handover
- IdleSleep 2s
- Ping ext-dn from NR-UE
- Verify UE(1) connected to DU-PCI1
Validate absence of heap-use-after-free ASAN error found in !3600.
Closes#940
- Simplify do_nrMeasurementReport_SA API (encoder allocates local report)
- Adopt asn1cCalloc consistently
- Minor init cleanup for UL_DCCH message struct
- Add to common/utils/nr/nr_common remove from NR_MAC_UE/nr_ue_procedures.c
- Adopt in asn1_msg.c for MeasurementReport: this solves the following assert:
Assertion (enc_rval.encoded > 0) failed!
In do_nrMeasurementReport_SA() /oai-ran/openair2/RRC/NR/MESSAGES/asn1_msg.c:898
ASN1 message encoding failed (MeasResultServMOList, 18446744073709551615)!
Motivation: unify RSRP-to-index mapping across layers and fix NR RRC MeasurementReport
encoding failures due to out-of-range values by reusing the validated mapping.
Note NR_RSRP-Range.c constraint:
{ APC_CONSTRAINED, 7, 7, 0, 127 } /* (0..127) */
- Remove unnecessary NULL assignment for dedicatedNAS_Message->buf
- The original buffer is copied and transfered to NAS, so it can be properly freed by ASN.1 structure cleanup
Root cause: Code was nullifying dedicatedNAS_Message->buf pointer before ASN.1 cleanup could free the original allocation, causing the leak from OCTET_STRING_decode_uper.
AddressSanitizer leak trace (FIXED):
Direct leak of 119 byte(s) in 3 object(s) allocated from:
/#0 0x7ec2a42b4c38 in __interceptor_realloc
/#1 0x555fade852e0 in OCTET_STRING_decode_uper
/#9 0x555fadb48b11 in nr_rrc_ue_decode_dcch.
The leak was caused by improper memory ownership handling in the
dedicatedNAS_MessageList processing. The function was transferring
buffer ownership to NAS messages and then preventing ASN.1 cleanup
from freeing the original allocations by setting
list.count = 0, causing a memory leak.
Leak trace:
Direct leak of 40 byte(s) in 1 object(s) allocated from:
/#0 0x7f2ce3ab4a57 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
/#1 0x567907083f0f in OCTET_STRING_decode_uper /cmake_targets/ran_build/build/openair2/RRC/LTE/MESSAGES/OCTET_STRING_uper.c:89
/#2 0x5679070ed5e6 in SET_OF_decode_uper /cmake_targets/ran_build/build/openair2/RRC/NR/MESSAGES/constr_SET_OF_uper.c:70
/#3 0x56790707b6dc in SEQUENCE_decode_uper /cmake_targets/ran_build/build/openair2/RRC/LTE/MESSAGES/constr_SEQUENCE_uper.c:118
/#4 0x56790707b6dc in SEQUENCE_decode_uper /cmake_targets/ran_build/build/openair2/RRC/LTE/MESSAGES/constr_SEQUENCE_uper.c:118
/#5 0x56790709a403 in CHOICE_decode_uper /cmake_targets/ran_build/build/openair2/RRC/LTE/MESSAGES/constr_CHOICE_uper.c:84
/#6 0x56790707b6dc in SEQUENCE_decode_uper /cmake_targets/ran_build/build/openair2/RRC/LTE/MESSAGES/constr_SEQUENCE_uper.c:118
/#7 0x56790709a403 in CHOICE_decode_uper /cmake_targets/ran_build/build/openair2/RRC/LTE/MESSAGES/constr_CHOICE_uper.c:84
/#8 0x56790709a403 in CHOICE_decode_uper /cmake_targets/ran_build/build/openair2/RRC/LTE/MESSAGES/constr_CHOICE_uper.c:84
/#9 0x56790707b6dc in SEQUENCE_decode_uper /cmake_targets/ran_build/build/openair2/RRC/LTE/MESSAGES/constr_SEQUENCE_uper.c:118
/#10 0x56790708b5f1 in uper_decode /cmake_targets/ran_build/build/openair2/RRC/LTE/MESSAGES/uper_decoder.c:83
/#11 0x567906d44b4b in nr_rrc_ue_decode_dcch /openair2/RRC/NR_UE/rrc_UE.c:2212
/#12 0x567906d520a3 in rrc_nrue /openair2/RRC/NR_UE/rrc_UE.c:2615
/#13 0x567906d5f77e in rrc_nrue_task /openair2/RRC/NR_UE/rrc_UE.c:2501
/#14 0x7f2ce2494ac2 in start_thread nptl/pthread_create.c:442
Fix:
- Copy OCTET_STRING data instead of transferring ownership
- Allow ASN.1 cleanup to properly free original allocations
This fixes the leak that occurred during rrcReconfiguration
message processing when dedicatedNAS_MessageList was present.
Closes#828
- Replace asn1cFreeStruc with ASN_STRUCT_FREE in MAC layer cleanup
- Fixes improper memory management of NR_CellGroupConfig structures
Root cause: asn1cFreeStruc only calls ASN_STRUCT_RESET + free(), which doesn't properly free nested ASN.1 allocations. ASN_STRUCT_FREE frees all nested structures completely.
AddressSanitizer leak trace:
Direct leak of 288 byte(s) in 1 object(s) allocated from:
/#0 0x7fb72bab4a57 in __interceptor_calloc
/#1 0x593752b28d0d in SEQUENCE_decode_uper
/#2 0x593752b9a546 in SET_OF_decode_uper
/#3 0x593752b2863c in SEQUENCE_decode_uper
/#4 0x593752b47363 in CHOICE_decode_uper
/#5 0x593752b2863c in SEQUENCE_decode_uper
/#6 0x593752b2863c in SEQUENCE_decode_uper
/#7 0x593752b2863c in SEQUENCE_decode_uper
/#8 0x593752b2863c in SEQUENCE_decode_uper
/#9 0x593752b2863c in SEQUENCE_decode_uper
/#10 0x593752b38551 in uper_decode
/#11 0x5937527d859f in nr_rrc_ue_process_masterCellGroup
/#12 0x5937527d9408 in nr_rrc_process_reconfiguration_v1530
/#13 0x5937527dd5bb in nr_rrc_ue_process_rrcReconfiguration
/#14 0x5937527f5e6b in nr_rrc_ue_decode_dcch
/#15 0x5937527ff003 in rrc_nrue
/#16 0x59375280c6de in rrc_nrue_task
- Move 'What is a gNB neighbor?' explanation from rrc-usage.md to handover-tutorial.md where it belongs
- Replace generic parameter names with actual configuration parameter names and specific descriptions (e.g. gNB_ID, nr_cellid)
- Add example configuration structure showing proper syntax
- Add missing 'band' parameter that was not listed before
- Provide concrete examples and exact constraints for each parameter
- Cross-reference between documents for better organization
This addresses documentation issues where generic parameter descriptions were
not useful for developers configuring neighbor cells.
- Remove extensive traffic testing before HO (iperf tests 030001, 030002)
- Do 1 ping test after attachment
- Reduce ping packet count from 100 to 50 packets for remaining connectivity test
Time savings: ~2-3 minutes by removing traffic validation overhead
Split monolithic e1_send_bearer_updates into three focused functions:
- e1_send_bearer_updates(): DRB setup from F1 UE Context Modification Response
- e1_request_pdcp_status(): Request PDCP status during inter-CU handover
- e1_notify_pdcp_status(): Notify CU-UP with PDCP status during handover
Extract common helpers:
- append_e1_drb_mod_req(): Common DRB-to-mod for bearer request logic
- e1_send_bearer_modification_request(): Common sending step
Bug fixes:
- Fix loop bounds (i < n instead of i == n)
- Fix array access bounds checking
- Fix DRB ID consistency
Memory management:
- Add missing free_e1ap_context_mod_request calls
- Improve error handling with early returns
In the process:
- Simplify cuup_notify_reestablishment with FOR_EACH_SEQ_ARR loop
- Adopted all callers to use new consolidated functions
Improves maintainability and eliminates complex conditional logic.
Replace field-by-field assignment with struct copy for plmn_identity.
Both source and destination use identical plmn_id_t type, making
this change safe and more maintainable.
- Reduces lines of code
- More readable and less error-prone
- Single memory copy operation instead of multiple field assignments
- ngap_gNB_handover_notify: Fix misleading error message from 'Failed to encode'
to 'Failed to find UE context' for better clarity
- ngap_gNB_handle_ul_ran_status_transfer: Standardize error message format
from 'Could not find' to 'Failed to find' for consistency across functions
This ensures consistent and accurate error reporting across all NGAP handover functions.
- Update encoder functions in ngap_gNB_mobility_management.c to use calloc_or_fail
- Provides zero-initialized memory and consistent error handling
- Prevents uninitialized fields and improves memory safety
Also:
- Update NG Setup Request to use calloc_or_fail
- Replace inefficient 'allocate, extract, free' pattern with direct value extraction
- Remove unused functions get_gap_config_from_smtc() and get_gap_config()
- Add extract_gap_config_from_smtc() that extracts values directly without allocation
- Eliminates use-after-free risk and improves performance
- No allocation overhead, no memory leaks
- Add missing ASN_STRUCT_FREE for NR_MeasGapConfig in create_measgap_config
- Fix 48-byte measurement gap config leak in get_gap_config_from_smtc
AddressSanitizer backtrace:
Direct leak of 48 byte(s) in 1 object(s) allocated from:
/#0 0x7d32adab4a57 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
/#1 0x5751f99cbb79 in calloc_or_fail /home/guido/repo/openairinterface5g/develop/common/utils/utils.h:74
/#2 0x5751f99cbb79 in get_gap_config_from_smtc /home/guido/repo/openairinterface5g/develop/openair2/LAYER2/NR_MAC_gNB/nr_radio_config.c:4164
/#3 0x5751f99cbb79 in create_measgap_config /home/guido/repo/openairinterface5g/develop/openair2/LAYER2/NR_MAC_gNB/nr_radio_config.c:4310
/#4 0x5751f9964abe in ue_context_setup_request /home/guido/repo/openairinterface5g/develop/openair2/LAYER2/NR_MAC_gNB/mac_rrc_dl_handler.c:709
/#5 0x5751f979e568 in nr_initiate_handover /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB_mobility.c:218
/#6 0x5751f97a637f in nr_rrc_trigger_n2_ho_target /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB_mobility.c:526
/#7 0x5751f9703608 in rrc_gNB_process_e1_bearer_context_setup_resp /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB.c:2641
/#8 0x5751f9706b7b in rrc_gnb_task /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB.c:3020
/#9 0x7d32ac494ac2 in start_thread nptl/pthread_create.c:442
Root cause: create_measgap_config allocated NR_MeasGapConfig via get_gap_config_from_smtc()
but never freed it after extracting the needed values to populate the measgap_config_t
return structure.
- Add missing handover context cleanup in rrc_CU_process_ue_context_release_complete
- Fix 16-byte handover context leak in N2 handover source gNB trigger path
AddressSanitizer backtrace:
Direct leak of 16 byte(s) in 1 object(s) allocated from:
/#0 0x7fee67cb4a57 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
/#1 0x58059e33454b in calloc_or_fail /home/guido/repo/openairinterface5g/develop/common/utils/utils.h:74
/#2 0x58059e33454b in alloc_ho_ctx /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB_mobility.c:47
/#3 0x58059e339e4d in nr_rrc_trigger_n2_ho /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB_mobility.c:556
/#4 0x58059e33ae93 in nr_HO_N2_trigger_telnet /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB_mobility.c:611
Root cause: Handover context allocated in N2 handover source gNB trigger path (nr_rrc_trigger_n2_ho)
for any successful N2 handover but not properly freed in all handover completion scenarios.
The UE context release complete handler was missing cleanup for handover context.
Solution: refactor handover context cleanup
- Move nr_rrc_finalize_ho() call to rrc_delete_ue_data() for centralized cleanup
- Remove redundant nr_rrc_finalize_ho() calls from handover failure paths:
* rrc_CU_process_ue_context_release_request() - UE not deleted yet
* invalidate_du_connections() - UE will be deleted later
- Keep nr_rrc_finalize_ho() calls in handover success paths where UE continues operating
- Ensures handover context is cleaned up exactly once when UE is actually deleted
- Prevents potential double-free and use-after-free issues in handover cleanup
This centralizes all UE data cleanup in rrc_delete_ue_data() and ensures
handover context is properly managed throughout the UE lifecycle and cleaned up
when UE delete happens.
- Add missing ASN_STRUCT_FREE for NR_MeasurementTimingConfiguration in ue_context_setup_request
- Fix 64-byte MTC sequence leak in get_nr_mtc → SEQUENCE_decode_uper
AddressSanitizer backtrace:
Direct leak of 64 byte(s) in 1 object(s) allocated from:
/#0 0x7dcfcb8b4a57 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
/#1 0x591fcc59b67d in SEQUENCE_decode_uper /home/guido/repo/openairinterface5g/develop/cmake_targets/ran_build/build/openair2/RRC/LTE/MESSAGES/constr_SEQUENCE_uper.c:37
/#2 0x591fcc57eaa1 in uper_decode /home/guido/repo/openairinterface5g/develop/openair2/RRC/LTE/MESSAGES/uper_decoder.c:83
/#3 0x591fcbdbedeb in get_nr_mtc /home/guido/repo/openairinterface5g/develop/openair2/LAYER2/NR_MAC_gNB/nr_radio_config.c:4216
/#4 0x591fcbd58188 in ue_context_setup_request /home/guido/repo/openairinterface5g/develop/openair2/LAYER2/NR_MAC_gNB/mac_rrc_dl_handler.c:635
/#5 0x591fcbb92568 in nr_initiate_handover /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB_mobility.c:218
/#6 0x591fcbb9a37f in nr_rrc_trigger_n2_ho_target /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB_mobility.c:526
/#7 0x591fcbaf7608 in rrc_gNB_process_e1_bearer_context_setup_resp /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB.c:2640
/#8 0x591fcbafab7b in rrc_gnb_task /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB.c:3019
/#9 0x7dcfca294ac2 in start_thread nptl/pthread_create.c:442
Root cause: ue_context_setup_request allocated NR_MeasurementTimingConfiguration via
get_nr_mtc() but never freed it after creating the measurement gap configuration.
The create_measgap_config function only reads from the structure and doesn't take
ownership, so the caller must free it.
- Replace heap allocation with stack allocation for seq_arr_t structures
- Use proper seq_arr_free() with free functions for ASN.1 structures
- Remove unnecessary malloc/free calls for sequence containers
- Improve memory safety and performance with automatic cleanup
Fixes 128-byte memory leak:
Direct leak of 128 byte(s) in 2 object(s) allocated from:
/#0 0x7e7f39ab4a57 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
/#1 0x56df8b07312d in SEQUENCE_decode_uper /home/guido/repo/openairinterface5g/develop/cmake_targets/ran_build/build/openair2/RRC/LTE/MESSAGES/constr_SEQUENCE_uper.c:37
/#2 0x56df8b056551 in uper_decode /home/guido/repo/openairinterface5g/develop/cmake_targets/ran_build/build/openair2/RRC/LTE/MESSAGES/uper_decoder.c:83
/#3 0x56df8a896b1b in get_nr_mtc /home/guido/repo/openairinterface5g/develop/openair2/LAYER2/NR_MAC_gNB/nr_radio_config.c:4216
/#4 0x56df8a82feb8 in ue_context_setup_request /home/guido/repo/openairinterface5g/develop/openair2/LAYER2/NR_MAC_gNB/mac_rrc_dl_handler.c:635
/#5 0x56df8a66a298 in nr_initiate_handover /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB_mobility.c:218
/#6 0x56df8a6720af in nr_rrc_trigger_n2_ho_target /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB_mobility.c:526
/#7 0x56df8a5cf338 in rrc_gNB_process_e1_bearer_context_setup_resp /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB.c:2633
/#8 0x56df8a5d28ab in rrc_gnb_task /home/guido/repo/openairinterface5g/develop/openair2/RRC/NR/rrc_gNB.c:3012
/#9 0x7e7f38494ac2 in start_thread nptl/pthread_create.c:442
- Add early check for existing UE context by AMF UE NGAP ID at beginning of rrc_gNB_process_Handover_Request
- Add dedicated function to get UE context by AMF UE NGAP ID: rrc_gNB_get_ue_context_by_amf_ue_ngap_id()
- Send handover failure with appropriate cause if UE context already exists
- Remove redundant ho_context NULL check that could never be true for newly created UE contexts
- Prevents duplicate handover processing and resource leaks
Move UE context creation and storage to after successful PDU encoding
to prevent memory leaks if encoding fails. Also add proper PDU cleanup
when AMF fetch fails and use consistent NULL check style.
This ensures UE context is only stored when the operation is guaranteed
to succeed, improving error handling and memory management.
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.
- Add proper cleanup of allocated ASN.1 structures in all return paths
- Fix early returns that were leaking NR_HandoverPreparationInformation
- Fix early returns that were leaking NR_RRCReconfiguration
- Add cleanup at end of successful function execution
This prevents memory leaks when processing handover preparation information
during N2 handover procedures.
- Add UE context cleanup before sending handover failure message
- Prevents memory/resource leak when PDU session establishment fails during handover
- UE context was created but never cleaned up on failure path
This fixes a bug where UE contexts would accumulate over time
when handovers failed after context creation.
- Replace error handling for impossible ID mismatches with DevAssert statements
- If ngap_get_ue_context() succeeds, returned context must have matching NGAP gNB UE IDs by definition
- This catches potential bugs in the lookup function immediately
- Affects: handover_required, handover_notify, handover_cancel, ul_ran_status_transfer
These checks were logically impossible since we looked up the context using
the same IDs we were then checking for mismatch.
- Fixed incorrect log messages that said 'PCI=%lu' when printing nr_cell_id
- Now prints both NR Cell ID and PCI when DU is found
- Provides better debugging information for handover requests
- Add _E1_EQ_CHECK_OPTIONAL_PTR checks for pdcp_config, sdap_config, UP_TL_information, and securityIndication
- Fix bug in eq_pdu_session_to_mod_item where a->UP_TL_information was compared with itself instead of b->UP_TL_information
- Fix eq_security_ind call to properly handle return value with early return pattern
- Improve consistency with existing macro usage patterns in the codebase
- Provide better error reporting for optional pointer field mismatches
Replace result &= pattern with consistent early return pattern:
- Fix mixing of logical (&&) and binary (&) operators
- Use consistent 'if (!eq_()) return false;' pattern throughout
- Fix bug in eq_bearer_context_mod_response where drbModA was compared with itself
- Remove unused 'bool result = true;' variables
- Always return true at the end of equality functions
This makes the code more consistent with the rest of the codebase
and provides better error reporting through the existing _E1_EQ_CHECK macros.
- Replace simple counter-based DRB ID assignment with actual DRB ID lookup
- Add nested loop to iterate through DRBs for each PDU session to be release
- Improve logic flow with early continue for non-matching PDU sessions
This ensures DRB release list contains correct DRB IDs that correspond to actual DRB entities
* 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.
Motivation:
The previous architecture had several issues:
- Duplicate DRB generation logic in generateDRB() and generateDRB_ASN1()
- Embedded SDAP/PDCP configs in drb_t created tight coupling
- No clear separation between RRC internal state and ASN.1 encoding
- Maintenance burden due to duplicated configuration logic
New Architecture:
- drb_t now only stores DRB-specific data (ID, PDU session ID, PDCP config)
- SDAP configuration moved to PDU session level (following PDCP design pattern)
- ASN.1 encoding helpers (nr_rrc_build_*_config_ie()) handle conversion
- Single source of truth for DRB creation in RRC via nr_rrc_add_drb()
Key changes:
- Store nr_sdap_configuration_t per PDU session
- Simplified drb_t structure: removed embedded SDAP/PDCP configs, added pdusession_id
- New helper: nr_rrc_build_sdap_config_ie()
- Updated createDRBlist() to use new helper functions and proper DRB ID lookup
- Refactored trigger_bearer_setup() to use nr_rrc_add_drb() and fill_e1_drb_to_setup()
- Removed generateDRB() and generateDRB_ASN1() functions
- Updated set_bearer_context_pdcp_config() to return config by value
- Added SDAP configuration header file for type definitions
This eliminates code duplication, improves maintainability, and creates
a cleaner separation between RRC state management and ASN.1 encoding.
- Move QoS-related enums and structures from ngap_messages_types.h to 5g_platform_types.h
- Replace ngap_* QoS types with generic qos_* types for better reusability
- Update field names from allocation_retention_priority to arp for consistency
- Update all references across RRC and NGAP modules to use new type names
- Remove duplicate QoS type definitions from NGAP-specific header
This improves code organization by centralizing QoS parameter definitions
in a common platform types header and eliminates NGAP-specific naming
in favor of more generic, reusable type definitions.
The maximum number of QoS flows is 64.
- Replace QOSFLOW_MAX_VALUE with MAX_QOS_FLOWS constant
- Move MAX_QOS_FLOWS definition to common/platform_constants.h
- Remove duplicate QOSFLOW_MAX_VALUE definition from ngap_messages_types.h
This improves maintainability by centralizing the QoS flow limit constant
and eliminates duplicate definitions across different header files.
- Limit scope of get_default_rbconfig function: from asn1_msg.c/.h to rrc_gNB_nsa.c where it's used
- Create new rrc_gNB_asn1.c/h files for ASN.1 utility functions: they can be used in other RRC files
- Add nr_rrc_build_pdcp_config_ie function for building PDCP configuration IEs
- Update get_default_rbconfig to use the new PDCP config builder
- Add rrc_gNB_asn1.c to CMakeLists.txt build configuration
The previous DRB management relied on a fixed-size array (established_drbs[MAX_DRBS_PER_UE])
and manual status tracking using DRB_ACTIVE/INACTIVE flags. This approach was inefficient,
and made assumptions about DRB ID allocation that do not generalize well
to dynamic procedures like bearer modification or removal.
* Replace fixed-size array established_drbs[] with dynamic
seq_arr_t *drbs in gNB_RRC_UE_t
* Refactor get_drb() and added nr_rrc_add_drb() with clean abstractions
using find and seq_arr lib
* Updated all DRB-related logic (e.g., generateDRB,
F1AP/E1AP tunnel config, reestablishment, mobility) to use seq_arr.
* Removed status field and DRB_ACTIVE/INACTIVE logic: list presence implies active
* DRB ID allocation now tracked via seq_arr size : simplifies DRB management and
avoids DRB ID–indexed assumptions: code assumed DRB IDs mapped directly to
array indices: established_drbs[drb_id - 1]. This could break when:
DRB IDs are not sequential, DRBs are removed and re-added, or there are gaps in IDs
The RRC PDU Session struct is converted from a fixed-size array
to a dynamically sized seq_arr. This improves flexibility and
simplifies session management by eliminating arbitrary size limits
and enabling dynamic addition/removal of PDU sessions.
Helper functions and loops have been adapted to use the seq_arr API.
This change is a step toward more robust and maintainable handling
of PDU sessions in the gNB RRC layer.
The "status" state machine remains untouched in this commit and
is refactored in a later commit.
Also:
* add macro to push to seq_arr and return the new element
* move initialization of xid (RRC PDU Session struct) to
find_pduSession (temporary, will be finalized in a later
commit) since with the new seq_arr design the initialization
is no longer possible in the UE context generation (also
does not belong to it, initialize when adding a new PDU Session)
The function was printing a "not found" error message even in the case
the return value was set to "true". Return directly true/false.
This is relevant in PDU Session Release procedures.
- Process all PDU sessions in handover request instead of only the first one
- Add DevAssert for bounds checking on nb_of_pdusessions
- Fix logic error where multiple PDU sessions were ignored in handover scenarios
Previously, the RRC layer was incorrectly allocating stack memory for the ho_required_transfer field and passing it to NGAP, however it was not used. The IE is mandatory but contains only 1 optional IE, therefore is encoded in the NG message with empty content.
Changes:
- Remove unnecessary ho_required_transfer field from pdusession_resource_t definition, the IE is encoded anyway with empty content. If Direct Forwarding Path Availability is needed at any stage in the future it can be added to pdusession_resource_t and filled in RRC.
- Add clarifying comment about empty HandoverRequiredTransfer structure
Guido Casati