A DRB To Modify Item contains a Flow Mapping Information,
which overrides previous mapping information. For consistency,
rename the count member to reflect a QoS Flow modification,
since it is not limited to setup only.
- Rename DRB flow mapping counters to `numQosFlowsMod`
for a DRB To Modify List
- Adjust encode/decode/equality + E1AP tests
Add DRB To Remove List IE to PDU Session To Modify list, which is sent
in the Bearer Context Modification request. This allows the CUCP to
inform the CUUP about DRBs to be released in a specific PDU session
during a MODIFY procedure.
Changes:
* Add struct definition
* Add enc/dec/eq/cp func
* Add test
- Delete drbs field from gNB_RrcConfigurationReq and its use in RCconfig_NRRRC()
- Remove GNB_CONFIG_STRING_DRBS, help text, index, and GNBPARAMS_CHECK entry from gnb_paramdef.h
- Drop DU-side verification and DRB count logging in gnb_config.c
During F1 handover reestablishment, the CU may forward a DL RRC
Message Transfer to the target DU with old_gNB_DU_ue_id included,
even though the target DU does not have the old UE context yet.
The code previously used AssertFatal when the old UE context was
not found, causing a crash: CU claims we should know UE %04x, but we don't
According to TS 38.473, the gNB-DU shall release the old gNB-DU UE
F1AP ID only "if the gNB-DU identifies the UE-associated logical
F1-connection". If there is no matching connection, there is nothing
to release.
However, the primary purpose of DL RRC MESSAGE TRANSFER is to deliver
the RRC message to the UE. The RRC message delivery is independent of
whether the old UE context can be retrieved. Per TS 38.473, the RRC
message must be delivered to the new UE regardless of old context
retrieval status.
Additionally, per TS 38.331 5.3.7.2 and 5.3.7.4, during reestablishment:
- The UE releases spCellConfig, which must be removed from CellGroupConfig
- SRB1 RLC must be reconfigured with specific parameters
These operations are required for the new UE during reestablishment and
are independent of whether the old UE context can be retrieved.
Fixes:
- Check if old UE context exists before accessing it
- If old UE does not exist, log error and clean up any stale F1 UE data,
but continue to deliver the RRC message
- Restructure code so context transfer only happens when oldUE exists
- Keep GTP-U update and RLC context transfer inside oldUE check (they
require old UE context to exist)
- Move spCellConfig handling and reestablish_rlc flag to execute
regardless during re-establishemnt (per TS 38.331 5.3.7.2)
- Move SRB1 RLC reconfiguration outside the oldUE check so it executes
regardless during re-establishment (per TS 38.331 5.3.7.4)
- Add function documentation and improve spec references in comments
This commit fixes the timing of SRB and DRB PDCP re-establishment
during RRC connection re-establishment to align with 3GPP TS 38.331
specifications.
Key Changes:
1. SRB1 activation and re-establishment (TS 38.331 5.3.7.4):
- Move SRB1 activation to rrc_gNB_generate_RRCReestablishment()
- Use SRB1 constant instead of magic number 1 for clarity
- Remove redundant security configuration loop (handled by
nr_pdcp_reestablishment internally)
2. SRB2 re-establishment (TS 38.331 5.3.5.6.3 SRB addition/modification):
- Move SRB2 PDCP re-establishment from rrc_gNB_process_RRCReestablishmentComplete()
to rrc_gNB_generate_dedicatedRRCReconfiguration(): per spec: SRB2
should be re-established in the first RRCReconfiguration after
re-establishment (with reestablishPDCP=true flag)
3. DRB re-establishment (TS 38.331 5.3.5.6.5 DRB addition/modification):
- Move cuup_notify_reestablishment() from rrc_gNB_process_RRCReestablishmentComplete()
to rrc_gNB_generate_dedicatedRRCReconfiguration(). e.g at the first
reconfiguration after reestablishment
- Ensures CU-UP is notified at the correct time
As per TS 38.401 §8.7: if the UE accesses a DU different from the original
one during re-establishment, the CU must trigger UE Context Setup toward
the new DU. This refers to steps 9-10 and steps 9'-10'. Either one or the
other can be executed during re-establishment.
e.g. if this happens during F1 handover, it shall trigger a
UE Context Setup fallback on the CU.
This commit implements the required behavior:
1. Detection mechanism:
- Add `old_du_assoc_id` field to `f1_ue_data_t` to store the original
DU association ID
- At RRCReestablishmentRequest: Store original `du_assoc_id` in
`old_du_assoc_id` and update `du_assoc_id` to the new DU
- At RRCReestablishmentComplete: Compare `old_du_assoc_id` with the
`assoc_id` from the Complete message to detect different DU
2. UE Context Setup trigger:
- In `rrc_gNB_process_RRCReestablishmentComplete()`: When different DU
is detected, call `rrc_f1_ue_context_setup_for_target_du()` to trigger
UE Context Setup procedure (per TS 38.401 §8.7, NOTE on steps 9-10)
upon reception of UL RRC MESSAGE TRANSFER
- In `rrc_CU_process_ue_modification_required()`: Refuse UE Context
Modification Required when `old_du_assoc_id != 0` to avoid conflicts
with the ongoing UE Context Setup procedure (per TS 38.401 §8.7, NOTE
on steps 9'-10')
3. UE Context Setup:
- Replace `clone_CellGroupConfig()` with `get_cellgroup_config()` in
UE Context Setup handler
- Call `update_cellgroup_for_reestablishment()` during UE Context Setup
when `reestablish_rlc` flag is set to prepare CellGroupConfig with
reestablishRLC flags
- Clean up `old_du_assoc_id` in `rrc_CU_process_ue_context_setup_response()`
- Add `free_ue_context_mod_req()` call after UE Context Modification request
4. Function signature updates:
- Update `handle_rrcReestablishmentComplete()` to accept `gNB_DU_ue_id`
and `assoc_id` parameters, change return type from `int` to `void`
- Update `rrc_gNB_process_RRCReestablishmentComplete()` to accept
`assoc_id` parameter
- Update `rrc_gNB_decode_dcch()` to accept and forward `assoc_id` parameter
Re-establishment on different DU flow (TS 38.401 §8.7, steps 9-10):
1. UE sends RRCReestablishmentRequest to new DU
2. DU forwards to CU via UL RRC MESSAGE TRANSFER
3. CU detects different DU (`assoc_id != ue_data.du_assoc_id`):
- Stores `old_du_assoc_id = ue_data.du_assoc_id` (original DU)
- Updates `ue_data.du_assoc_id = assoc_id` (new DU)
4. CU sends RRCReestablishment to UE
5. UE sends RRCReestablishmentComplete to new DU
6. DU forwards to CU via UL RRC MESSAGE TRANSFER
7. CU detects different DU scenario (with old_du_assoc_id):
- Triggers UE Context Setup Request to new DU via `rrc_f1_ue_context_setup_for_target_du()`
8. DU receives UE Context Setup Request:
- Detects re-establishment (`UE->reestablish_rlc` flag)
- Calls `update_cellgroup_for_reestablishment()` to set reestablishRLC flags
- Encodes CellGroupConfig with reestablishRLC flags and sends to CU
9. CU receives UE Context Setup Response:
- Stores encoded CellGroupConfig
- Clears `old_du_assoc_id = 0`
10. CU sends RRC Reconfiguration with transparent CellGroupConfig to UE
This commit implements transparent forwarding of CellGroupConfig
as required by TS 38.473, eliminating CU-side decode/re-encode
cycles that violate transparency requirements.
Main Design Change:
- Before: CU decoded CellGroupConfig from DU, stored in the UE
context then re-encoded when sending to UE. CU constructed
new CellGroupConfig after RRCReestablishmentComplete.
- After: CU requests CellGroupConfig from DU via UE Context Modification
Request with `gNB_DU_Configuration_Query=true`, DU sends CellGroupConfig
which CU stores as encoded `byte_array_t` and forwards transparently
via reconfiguration without decode/re-encode cycles
To this purpose, all decode operations of CellGroupConfig were removed
from DU and all encode operations were removed from the CU.
Key Changes:
CU:
- Replace NR_CellGroupConfig_t* masterCellGroup with byte_array_t mcg in
gNB_RRC_UE_t for storing encoded CellGroupConfig
- Rename cell_group_config to cgc in nr_rrc_reconfig_param_t for brevity
- Implement transparent forwarding in build_RRCReconfiguration_IEs()
- Add helper functions:
- `store_cgc()` to store encoded bytes
- `get_meas_gap_config()`: Decode MeasGapConfig from DU to CU response
- `rrc_detect_reestablishment()` to detect re-establishment by decoding
temporarily (only for detection)
- Remove legacy decode/re-encode paths in RRC message generation
- Update all CellGroupConfig storage to use encoded bytes
- Update reconfiguration generation to accept is_reestablishment parameter
DU:
- Add `get_cellgroup_config()` to select source (CellGroup vs reconfigCellGroup)
based on re-establishment state
- Add re-establishment detection logic in `ue_context_modification_request()`
- Add `update_cellgroup_for_reestablishment()` to set reestablishRLC flags and
remove SRB1 from bearer list
- When `gNB_DU_Configuration_Query` is present and re-establishment detected:
- Clones from reconfigCellGroup (which contains spCellConfig) instead of
CellGroup (where spCellConfig was removed)
- Sets `reestablishRLC` flags for all bearers except SRB1
- Removes SRB1 from bearer list (already re-established)
Data Structure Changes:
- gNB_RRC_UE_t: Add byte_array_t mcg field
- nr_rrc_reconfig_param_t: Change cell_group_config to cgc (byte_array_t*)
- Remove masterCellGroup field usage in favor of encoded mcg
New re-establishment flow:
1. UE sends RRCReestablishmentRequest
2. CU processes -> sends RRCReestablishment
3. CU sends RRCReestablishmentComplete
4. CU sends UE Context Modification Request to DU with `gNB_DU_Configuration_Query=true`
5. DU detects re-establishment (`UE->reestablish_rlc && UE->reconfigCellGroup != NULL`):
- Clones `UE->reconfigCellGroup` -> `new_CellGroup` (contains spCellConfig)
- Sets `reestablishRLC` flags for all bearers except SRB1
- Removes SRB1 from bearer list (already re-established)
- Encodes `new_CellGroup` and sends to CU
6. CU receives encoded CellGroupConfig -> stores in `UE->mcg` via `store_cgc()`
7. CU detects re-establishment via `rrc_detect_reestablishment()`
8. CU calls `rrc_gNB_generate_dedicatedRRCReconfiguration()` with `is_reestablishment=true`:
- Creates SRB/DRB lists with re-establishment flags
- Generates RRC Reconfiguration with transparent CellGroupConfig
- Sends to UE
Why spCellConfig must be added in the DU in case of re-establishment:
With transparent forwarding, CU requests CellGroupConfig from DU instead
of constructing it. During re-establishment, DU's runtime CellGroup has
spCellConfig = NULL (removed per TS 38.331 §5.3.7.2). However, for the
gNB_DU_Configuration_Query response, DU must provide a complete CellGroupConfig
including spCellConfig. Therefore, DU restores spCellConfig by encoding
reconfigCellGroup (with the original spCellConfig) in CellGroupConfig.
In the old design CU constructed CellGroupConfig itself in
`rrc_gNB_process_RRCReestablishmentComplete()` and used `spCellConfig`
from its stored `masterCellGroup`.
Closes#837
Apply CGC encoding through GNB-DU Configuration Query. This applies to the
pdu session release path (rrc_gNB_send_f1_drb_release_request) and E1 bearer
mod / DRB add+release path (rrc_gNB_generate_UeContextModificationRequest).
This is necessary to implement 3GPP TS 38.473 requirement for
gNB-DU Configuration Query IE in UE Context Modification Request:
"If the GNB-DU Configuration Query IE is contained in the UE CONTEXT
MODIFICATION REQUEST message, gNB-DU shall include the CellGroupConfig
IE in the DU To CU RRC Information IE in the UE CONTEXT MODIFICATION
RESPONSE message."
i.e.: The DU sends the CGC only when this IE is enabled in the REQ
message from the CU. The only other scenario according to the same
specs is when the Full Configuration IE is present. Outside of these
two cases, CGC shall not be sent.
This field will be adopted to trigger cgc encoding at DU,
according to the specs (see subsequent commit for details).
Changes:
- Add gNB_DU_Configuration_Query field to f1ap_ue_context_mod_req_t
- Implement encoding/decoding
- Add to cp, eq, and free functions for the new field
- Update tests to include the new field
Issue: sometimes it happens that an ul failure occurs in the handover
pipeline, UE reconnects with different UE ID and fetch_du_by_ue_id fails.
- Modified fetch_du_by_ue_id in telnetsrv_ci.c to automatically find
the connected UE when no UE ID is provided, similar to other
telnet commands like rrc_gNB_trigger_f1_ho
- Updated test cases in container_sa_f1_ho_b210_quectel.xml to use
the improved command without hardcoded UE ID parameter
- This makes the command more robust and easier to use in CI tests
Add debugging utilities dump_cgc() and dump_mcg() to decode and
print CellGroupConfig in XER format when DEBUG_ASN1 flag is enabled.
This helps debug RRC Reconfiguration messages containing masterCellGroup.
Add intermediate fallback to rrc_gNB_get_ue_context_by_rnti_any_du() in
re-establishment request handling to better handle cases where UE
re-establishes on a different DU.
RNTI is NOT globally unique - different DUs can assign the same RNTI to
different UEs. The assoc_id check in rrc_gNB_get_ue_context_by_rnti()
disambiguates RNTI across DUs and prevents returning the wrong UE.
However, during re-establishment on a different DU, du_assoc_id hasn't
been updated yet (message comes from new DU, but ue_data.du_assoc_id
still points to old DU), causing the primary lookup to fail even though
the UE exists.
The lookup now uses a three-tier fallback:
1. Primary: rrc_gNB_get_ue_context_by_rnti() with assoc_id check
(normal case: same DU)
2. Fallback 1: rrc_gNB_get_ue_context_by_rnti_any_du() by RNTI only
(re-establishment on different DU)
3. Fallback 2: rrc_gNB_get_ue_context_source_cell() using physCellId
(handover scenarios)
- Remove unused masterCellGroup_from_DU parameter from rrc_gNB_generate_RRCReestablishment() as it is not used in the RRC
re-establishment generation, RRCReestablishment message does not contain CellGroupConfig which is obtained later via UE Context Modification Request/Response
- Update function documentation
- Initialize security_parameters struct to zero for safety
- Add check on ciphering and integrity algorithm ranges
When a UE re-establishes on a different DU, the physCellId in the
re-establishment request (from the old cell) will differ from the
new DU's physCellId. The previous check incorrectly treated this as
a "too fast movement" scenario and triggered fallback to RRC setup.
This fix distinguishes between two scenarios:
1. Different DU scenario: physCellId differs because UE is on a
different DU - this is legitimate and should be allowed. UE
Context Setup will be triggered at RRCReestablishmentComplete.
2. Same DU but different physCellId: "too fast movement" scenario
- fallback to RRC setup as before.
The fix checks if assoc_id != ue_data.du_assoc_id to detect a
different DU scenario and allows re-establishment in that case.
This addresses the issue where re-establishment on a different DU
was incorrectly rejected, preventing proper UE Context Setup per
TS 38.401 Section 8.7.
Handle target DU UE context setup when handover preparation info
is unavailable (i.e. re-establishment scenario) by retrieving
secondary UE ID from F1 UE data.
rrc_f1_ue_context_setup_for_target_du is either applying to
handover or re-establishment. In the latter scenario, populate
DU UE ID, which should be known.
Extract the common RRC container handling logic from
ue_context_setup_request() and ue_context_modification_request() into
a new static function handle_ue_context_rrc_container().
This refactoring:
- Eliminates code duplication between the two functions
- Centralizes RRC container forwarding logic
- Improves code maintainability and consistency
Extract common CellGroupConfig encoding logic from
ue_context_setup_request() and ue_context_modification_request() into
encode_cellgroup_config().
Replace uper_encode_to_buffer() with uper_encode_to_new_buffer() to:
- Remove 1024-byte buffer size limit
- Automatically allocate correct buffer size
- Simplify code (no manual bit-to-byte conversion)
- Align with other protocol encoders
- Add function documentation blocks for `rrc_fill_f1_ue_context_setup`,
`rrc_f1_ue_context_setup_for_target_du`, and `rrc_f1_ue_context_setup_from_e1_response`
explaining their purpose, parameters, and usage scenarios
- Add inline comments throughout these functions
Improve maintainability by centralizing common F1AP UE context setup
logic into reusable helper functions, enabling consistent handling
and clear serving/target DU entry points for different scenarios.
Code duplication prevention is a beneficial side effect, since at
least one helper function is adopted in subsequent commits.
Major changes:
- Move DRB list filler from external file into rrc_gNB.c and rename
fill_drb_to_be_setup to rrc_fill_f1_drb_to_setup for naming
consistency
- Add static helper rrc_fill_f1_ue_context_setup to populate common
fields shared between serving DU and target DU scenarios:
- Rename rrc_gNB_generate_UeContextSetupRequest to
rrc_f1_ue_context_setup_from_e1_response to clarify it prepares
F1AP context setup from E1AP bearer setup response for serving DU
- Add rrc_f1_ue_context_setup_for_target_du (for target DU in
handover/reestablishment scenarios)
- Adopt helper rrc_fill_f1_ue_context_setup in both functions
When processing UL RRC messages from PDCP, the DU association ID (assoc_id)
was not being propagated to RRC, resulting in assoc_id being 0 in
rrc_gNB_decode_dcch.
Fix by setting originInstance in the ITTI message header to the stored
du_assoc_id from ue_data when PDCP creates the F1AP_UL_RRC_MESSAGE.
- Refactor function to return byte_array_t instead of taking buffer
parameter for consistency with other encoding functions
(do_RRCReconfiguration, do_HO_RRCReconfiguration) and to prevent buffer
overflow issues since the memory size is determined automatically
- Add comprehensive error checking:
* Input validation
* Check return of each decode (HandoverCommand
and RRCReconfiguration)
* Validate HandoverCommand structure before access
* Validate OCTET_STRING before decoding RRCReconfiguration
* Error handling and cleanup for enc/dec failures
- Update caller in rrc_gNB_NGAP.c
* use new signature
* free buffer
* send HO Cancel on decoding failure (source gNB)
Closes#1043
This commit adds support for the Handover Cancel initiating message
procedure code (NGAP_ProcedureCode_id_HandoverCancel).
Changes:
- ngap_gNB_decoder.c: Added case handler for Handover Cancel in
ngap_gNB_decode_initiating_message() to properly decode and log
incoming Handover Cancel messages from the AMF.
- ngap_gNB_encoder.c: Added Handover Cancel to the list of supported
initiating message procedure codes in ngap_gNB_encode_initiating(),
allowing the gNB to encode and send Handover Cancel messages.
The Handover Cancel procedure is already implemented in other parts of
the NGAP stack, these changes were missing to complete the support
by ensuring the procedure code is properly recognized in both the encoder
and decoder switch statements, following the same pattern as other
procedure codes.
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()
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)
Refactor key derivation logic to properly handle Next Hop (NH) chain
synchronization according to 3GPP TS 33.501 specifications for both
RRC Reestablishment and Master Key Update procedures.
Changes in rrc_gNB.c:
- Clarify key derivation in rrc_gNB_generate_RRCReestablishment by
explicitly selecting base key (NH or KgNB) based on nh_ncc value
- Add comment explaining vertical vs horizontal derivation logic
Changes in rrc_UE.c:
- Add nr_sync_nh_chain(): Common helper to synchronize NH parameter
chain per TS 33.501 Annex A.10, supporting both Master Key Update
and RRC Reestablishment procedures
- Add nr_derive_kgnb_horizontal(): Derive KNG-RAN* from current KgNB
when NCC values match (horizontal derivation per TS 33.501 A.11/A.12)
- Add nr_derive_kgnb_vertical(): Derive KNG-RAN* from synchronized NH
after NH chain sync (vertical derivation per TS 33.501 A.11/A.12)
- Add nr_update_kgnb_from_ncc(): Unified function implementing TS 33.501
6.9.2.3.4 logic for updating KgNB based on received nextHopChainingCount
- Refactor as_security_key_update(): Use new nr_update_kgnb_from_ncc()
helper function for cleaner, more maintainable code
- Fix nr_rrc_ue_process_rrcReestablishment(): Properly handle received
nextHopChainingCount and update KgNB using unified helper function
- Add debug logging for key derivation process
Key NAS deriver utils:
- update derive_kgnb documentation and protect input keys with const attribute
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.