In nr_sdap_rx_entity, the RX callback receives the DRB identity from PDCP
(drb-Identity). Rename pdcp_entity to drb_id to be aligned with TS 37.324 terminology.
Changes:
- Rename the RX callback argument through the full SDAP RX surface:
sdap_data_ind(), the rx_entity function pointer table, and nr_sdap_rx_entity().
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
After new per-DRB SDAP roles changes, UE downlink reflective mapping
(TS 37.324 §5.3.2) still stored only drb_id on the new QFI row.
entity_role stayed NO_SDAP_HEADER, so later uplink TX and §5.3.1
end-marker logic read the wrong header config from that row.
When storing the reflective UL rule, copy the receiving DRB entity_role
(from nr_sdap_drb_lookup) together with drb_id, matching qfi2drb_map_add.
Changes:
- nr_sdap_rx_entity(): set qfi2drb_table[qfi].entity_role on RDI store
Refs:
- TS 37.324 §5.3.1, §5.3.2
- TS 38.331 SDAP-Config (sdap-HeaderUL / sdap-HeaderDL)
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
Parent commits route QFI-to-DRB lookup through qfi2drb_map (including
default-DRB fallback per TS 37.324 clause 5.2.1), but gNB UL RX still
checked the raw mapping table and accepted any mapped QFI on whatever
DRB received the PDU.
On gNB UL SDAP PDUs with a header, nr_sdap_rx_entity resolves the QFI
through entity->qfi2drb_map, drops when no rule and no default DRB apply,
and drops when the resolved DRB does not match the receiving DRB before
GTP-U forwarding.
Changes:
- parse UL header with nr_sdap_ul_hdr_t
- call qfi2drb_map for QFI validation
- verify receiving-DRB match
- simplify gNB UL block
Refs:
- TS 37.324 clause 5.2.1 (Uplink), clause 6.2.2.3 (UL data PDU)
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
E1 DRB-To-Modify already carries the new QFI list. The old
nr_sdap_entity_update_qos_flows() duplicated that as a bare qfi[] plus other params
while map_update expects a full sdap_config_t (add/release lists and per-DRB
role). Route the E1 path through one struct instead.
Changes:
- nr_sdap_entity_update_qos_flows(): take sdap_config_t *, caller fills the struct,
function sets role and defaultDRB from qfi2drb_table, builds mappedQFIs2Release
for QFIs dropped from the DRB, then calls qfi2drb_map_update()
- cucp_cuup_handler.c: build stack sdap_config_t from E1 qosFlows[] and call
the new API
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
A DRB may have an uplink SDAP header but no downlink header (valid TS 38.331).
The old entity->enable_sdap flag was true if either direction had a header, so UE
downlink wrongly read byte 0 as QFI. IPv4 payloads start with 0x45 -> bogus QFI 5
and dropped traffic before the TUN (PR !158).
Header presence must follow TS 37.324 §5.2.1/§5.2.2 per DRB and direction, not a
single PDU-session-wide enable-sdap.
Also, store the default DRB as a `qfi2drb_t` mapping in the SDAP entity and use
it directly for fallback paths.
Changes:
- Add nr_sdap_drb_lookup() to return first qfi2drb_table row for a DRB
- nr_sdap_rx_entity(): parse QFI only when the receiving direction has a header,
drop if the DRB has no table row
- nr_sdap_tx_entity(): UL/DL TX header bits from qfi2drb_map() (drb_id + entity_role),
including default-DRB fallback
- nr_sdap_qfi2drb(): const qfi2drb_t *, remove SDAP_MAP_RULE_EMPTY
- nr_sdap_map_ctrl_pdu(): handle NULL from qfi2drb_map
- nr_sdap_qfi2drb_map_update(): sync entity_role on
all QFIs for the DRB. At most one DRB when both headers absent.
- nr_sdap_entity_update_qos_flows(): keep per-DRB role from nr_sdap_drb_lookup(),
skip update when DRB has no row
- Cleanup entity->enable_sdap
- nr_sdap.c: remove TUN-thread QFI drop, tx_entity owns unmappable-QFI handling
- replace default_drb with qfi2drb_t default_drb in SDAP entity and init
default DRB id+role at SDAP entity creation
Refs:
- PR #158
- TS 37.324 §5.2.1, §5.2.2, §6.2.2.1
- TS 38.331 SDAP-Config (sdap-HeaderUL / sdap-HeaderDL)
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
Remove an assert on successful dup() of a socket. At least when running
in phy-test mode without noS1, the socket does not exist, and the call
to dup() fails. In that case, we should carry on instead of simply
failing, similarly how the process does not abort when TUN setup fails.
Fixes: 8d2895463b ("Paging UE (SDAP): reattach TUN after idle reset")
Signed-off-by: Robert Schmidt <robert.schmidt@openairinterface.org>
- Add a LOG_I to 'nr_sdap_add_entity' to inform the user
a SDAP entity is being created
- Add LOG_W to `nr_sdap_get_entity` to warn about
empty SDAP entity list
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
UE paging can recreate the AS-side SDAP entity while NAS still keeps the
PDU session established. Per TS 38.304 clause 7.1 and TS 24.501 clauses
5.6.2.2.1,5.6.1.2 paging/service request restores user-plane resources
for an established PDU session, it does not imply deleting the UE IP/TUN
interface.
Deleting the UE TUN with SDAP entity teardown breaks user-plane continuity
after re-attach. We need SDAP entity lifetime and UE TUN lifetime to be
decoupled. This commit keeps a UE/PDU-session TUN registry outside the
SDAP entity lifetime. When a UE SDAP entity is recreated, reattach it
to the preserved TUN socket and restart the reader thread. On first PDU
session setup, NAS registers the TUN before attaching the reader.
The sequence is the following: (1) NAS register the iface
(2) sdap entity attaches to the iface (3) UE goes IDLE, SDAP
entity is destroyed, iface is deatched and brought down (4)
UE Service Request, SDAP entity is created (5) iface reattaches
to the SDAP entity and is brought up
UE reattach assumes the PDU session TUN interface was registered
before the SDAP entity is recreated.
DL/UL data is intentionally dropped when SDAP is not yet attached
or QFI is unavailable, rather than queued in this layer.
Changes:
- `nr_sdap.c`: keep a UE/PDU-session TUN registry, duplicate the stored
socket into each SDAP entity, and add attach/detach/destroy helpers.
- `nr_sdap_entity.c`: detach SDAP entities from their TUN reader on
deletion, preserve UE TUN interfaces across idle cleanup, and destroy
gNB TUN interfaces when the gNB entity is removed. Drop downlink SDUs
if the UE SDAP entity is not attached to a TUN socket yet.
- `openair3/NAS/NR_UE/nr_nas_msg.c`: set QFI before UE TUN creation so
first attach can pick up cached QFI.
- `common/utils/tuntap_if.c`: add `tuntap_set_up`/`tuntap_set_down` helpers
for UE interface state reflection and initialize `flags` in `tuntap_destroy`
to avoid maybe-uninitialized build failures.
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
This commit extends PDU Session Modify handling with E1AP Bearer Context
Modification integration for QoS flow add/modify/release and DRB lifecycle
updates (setup, modification, removal).
E1AP Bearer Context Modification - DRB Setup Support:
- Extend CU-UP handler (e1_bearer_context_modif) to process DRBs to setup/to remove:
create F1-U tunnels, create/release PDCP-SDAP resources, and update QoS flow mappings
- Extend CU-CP response handler to process DRBs to setup: save F1-U tunnel info,
mark PDU sessions for RRC reconfiguration, and trigger F1 UE Context
Modification Request with both setup and release DRBs
- Update rrc_gNB_process_e1_bearer_context_modif_resp to collect DRBs to
setup/release from E1 response, send F1 UE Context Modification when needed,
and otherwise trigger direct RRC reconfiguration or NGAP modify response.
- Populate the E1AP Bearer Context Modification request with DRB-To-Setup and
DRB-To-Modify lists derived from QoS flow processing. For CP->UP E1 Bearer
Context Modification, Flow Mapping Information in DRB-To-Modify carries
the QoS Flow QoS Parameters List for that DRB: per TS 38.463, when present,
CU-UP replaces the previous mapping for that DRB, and this behavior is now enforced.
RRC PDU Session Modify - QoS and DRB Management:
- Add nr_rrc_apply_qos_add_modify() to process QoS add/modify and map flows to
existing or new DRBs
- Add nr_rrc_apply_qos_release() and nr_rrc_apply_pdusession_modify() to
process QoS release, build E1 DRB setup/modify/remove lists, and prepare
bearer-context modification.
- Refactor nr_rrc_update_qos() processing for QoS add/modify,
with DRB mapping to existing or new DRBs through the modify path helpers
- Extend nr_rrc_update_pdusession() with helpers for QoS
add/modify/release, building E1 DRB modify/setup/remove lists, and
sending bearer-context modification.
- Integrate E1 Bearer Context Modification into PDU Session Modify flow to
propagate DRB changes to CU-UP
- Update default DRB in SDAP configuration after QoS changes
- Add `nr_sdap_entity_update_qos_flows` to replace DRB flow
mappings from E1 flow information and clear stale SDAP role/mapping
state when QFIs are removed.
Code Refactoring:
- Add find_or_add_pdu_session_mod() to create/reuse session entries
in the E1 Bearer Context Modification request while building message.
- Add nr_rrc_send_e1_after_qos_update() to detect DRBs left without mapped
QoS flows, remove them from UE state, and append them to E1 DRBs-to-remove.
- Use rrc_gNB_generate_dedicatedRRCReconfiguration instead of
rrc_gNB_modify_dedicatedRRCReconfiguration, drop the old function
End-to-End PDU Session Modify Flow:
1. AMF -> CU-CP: NGAP PDU Session Resource Modify Request (QoS add/modify/release)
2. CU-CP (RRC): Process QoS flows -> map to DRBs (reuse existing or create new) ->
populate E1AP Bearer Context Modification Request (DRBs to setup/modify/remove)
3. CU-CP -> CU-UP: E1AP Bearer Context Modification Request
4. CU-UP: Create F1-U tunnels for new DRBs -> create/release PDCP-SDAP
resources -> update DRB/QFI mapping information
5. CU-UP -> CU-CP: E1AP Bearer Context Modification Response (F1-U tunnel info)
6. CU-CP: If DRB setup/release exists, send F1 UE Context Modification Request
7. CU-CP: Else if QoS/NAS requires it, send direct RRC Reconfiguration
8. CU-CP: Else complete modify directly with NGAP PDU Session Resource Modify Response
9. UE -> CU-CP: RRC Reconfiguration Complete
10. CU-CP -> AMF: NGAP PDU Session Resource Modify Response
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
Refactor GTP-U tunnel and send APIs so QFI is handled when sending packets,
not stored in tunnel creation state. Update SDAP and CU-UP integration to
use PDU-session keyed N3 mappings and explicit QFI-marked sends.
This commit clarifies layering ownership: GTP-U stays transport-only (TEID
lookup, decapsulation, extension parsing, callback dispatch), while SDAP
owns QoS semantics (QFI handling, QoS-flow-to-DRB policy, default DRB behavior,
and mapping updates); GTP-U does not perform runtime QFI-to-DRB mapping or
synthesize QFI.
Changes:
- remove `outgoing_qfi` from `gtpv1u_gnb_create_tunnel_req_t` and stop storing
QFI as tunnel creation metadata; `newGtpuCreateTunnel(...)` now carries only
transport/tunnel identity parameters (incoming_bearer_id, outgoing_bearer_id,
outgoing_teid, remote address, callbacks)
- add `gtpv1uSendDirectWithQFI()` and pass QFI into `_gtpv1uSendDirect`
to build UL PDU Session Container extensions
- shift QFI handling from tunnel provisioning to per-packet TX APIs: QFI is passed
explicitly only when sending (`gtpv1uSendDirectWithQFI(...)`) and is absent from
non-SDAP/F1 sends (`gtpv1uSendDirect(...)`)
- align N3 tunnel request semantics with session-level keys by setting incoming_rb_id
to PDU session ID on N3 paths, while F1 paths keep DRB ID
- keep `gtpv1uSendDirect()` and `gtpv1uSendDirectWithNRUSeqNum()` on
`NO_QFI`, and enforce non-SDAP RX callback path only when QFI is absent
- update `nr_sdap_rx_entity` to extract/validate QFI from SDAP UL headers,
send UL data with `gtpv1uSendDirectWithQFI`, and use non-QFI send when
SDAP header is disabled
- add disabled-SDAP safety checks in SDAP entity setup/mapping to enforce
single-DRB and single-flow constraints per PDU session
- extend `test_gtp.cpp` with a `multi_qos_flows` scenario and QFI-aware send calls
- update `nr-cuup-load-test.c` bearer setup fields and tunnel creation calls
to match the new API
- update tests/nr-cuup/nr-cuup-load-test.c to set explicit PDU session and
QoS/SDAP parameters (sessionType, qosFlows[0], SDAP header flags), and to
migrate both N3 and F1 tunnel creation calls to the new newGtpuCreateTunnel(...)
signature (without outgoing_qfi)
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
According to 3GPP TS 37.324, there shall be only one default DRB per
SDAP entity (per PDU session). The previous implementation incorrectly
marked all DRBs as default, violating this requirement.
Changes:
- Add default_drb field to nr_sdap_configuration_t to track the default
DRB ID per PDU session
- Arbitrary set default DRB to the first DRB added when creating bearers in a
PDU session
- Update nr_rrc_build_sdap_config_ie() to accept defaultDRB (bool) parameter
instead of hardcoding true
- Use tracked default_drb value when building RRC SDAP Config IE
- Use tracked default_drb value when building E1AP DRB setup structure
Also:
- Fix include style in nr_sdap_configuration.h (<stdbool.h> instead of
"stdbool.h")
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
Replace incorrect mathematical range check with explicit bounds
validation in nr_sdap_delete_entity(). The previous condition
(pdusession_id) * (pdusession_id - NR_MAX_NB_PDU_SESSIONS) > 0
was mathematically incorrect and could fail to properly validate
PDU session IDs.
PDU session ID validation now correctly rejects values outside
the valid range [0, NR_MAX_NB_PDU_SESSIONS]
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
Replace NGAP_MAX_PDU_SESSION and E1AP_MAX_NUM_PDU_SESSIONS with
shared NR_MAX_NB_PDU_SESSIONS constant. The value (256) is consistent
with both TS 38.331, TS 38.413 and TS 38.463
All protocol layers (NGAP, E1AP, RRC, SDAP) now use a single
shared constant for maximum PDU sessions per UE, ensuring
consistency across the codebase
E1AP_MAX_NUM_PDU_SESSIONS (was 4) is removed from e1ap_messages_types.h
Signed-off-by: Guido Casati <guido.casati@openairinterface.org>
- all RAN code, CI code, configuration files, dockerfiles, in CSSL v1.0
- all deployment code (openshift, charts, ancillary files like shell
scripts), in MIT
- documentation in CC-BY-4.0
- exceptions might apply and are listed in NOTICE
- there is a new LICENSES folder with all licenses
- CONTRIBUTIONS.md has been updated accordingly
For automated changes based on OAI PL v1.1:
perl -i~ -0pe 's/\/\*.*Licensed to the OpenAirInterface.*openairinterface.org\n#?/\/*\n * SPDX-License-Identifier: LicenseRef-CSSL-1.0\n/s' **/*.{c,h,cpp}
perl -i~ -0pe 's/\/\*.*Licensed to the OpenAirInterface.*openairinterface.org\n#?/\/*\n * SPDX-License-Identifier: LicenseRef-CSSL-1.0\n/s' **/*.ts
perl -i~ -0pe 's/<!--.*Licensed to the OpenAirInterface.*openairinterface.org\n.*-->/<!-- SPDX-License-Identifier: LicenseRef-CSSL-1.0 -->/s' **/*.xml
The rest (cmake, files with missing license, cmake) manually.
Look up the index of a PDU session in the list of PDU sessions upon
accept to determine if the PDU session is the default (first PDU
session) or not. If it is the default, it will not append a suffix to
the interface name (oaitun_ueY), otherwise append the PDU session ID
(e.g., for 5: oaitun_ueYp5).
Modify all functions to also handle TAP (where applicable). The actual
TAP interface code is not used in this commit, it will be used later.
To make the interface creation stand out, make "Interface XXX
successfully configured" a LOG_A.
Simplify interface handling by storing the name: this allows to simplify
to remove_ip_if(), which does not need to recreate a valid name, and
will simplify handling of ethernet PDU sessions with a possibly
different name.
Defacto, the PDU session ID for noS1 modes is already hardcoded, as
starting the nr-softmodem with --noS1 --default-pdu-id 1 leads to
Assertion (entity != ((void *)0)) failed!
In start_sdap_tun_gnb_first_ue_default_pdu_session() openair2/SDAP/nr_sdap/nr_sdap.c:163
Further, the --default-pdu-id parameter will be deactivated in a later
commit, and we cannot rely on it. Therefore:
- hardcode noS1 PDU ID (also used in --do-ra/--phy-test modes) to 10 and
use in gNB&UE
- pass the PDU session ID used in SDAP entity initialization down to
start_sdap_tun_gnb_first_ue_default_pdu_session() to always use the
correct one
PDU Session Release
This MR implements end-to-end PDU Session Release functionality
according to 3GPP TS 38.413 and TS 38.331 specifications.
Reason for Change Previous implementation had incomplete and wrongly
places tunnel cleanup during PDU session release. UP cleanup shall be
done at CUUP, RRCReconfiguration shall be sent after retrieval of
updated CellGroupConfig from the DU. This implies F1 and E1 exchanges
during PDU session release procedure.
Major Changes:
1. RRC PDU Session Release: DRBs and PDU session teardown in NGAP PDU
Session Release Response callback
- Helper Functions: Introduced rm_pduSession,
find_drb_by_pdusession_id and rm_drbs() helpers to locate and clean
up DRBs linked to a specific PDU session
- Targeted Cleanup: RRC PDU Session and per-session DRB removal in
rrc_gNB_send_NGAP_PDUSESSION_RELEASE_RESPONSE()
- Status Cleanup: Removed unused PDU_SESSION_STATUS_RELEASED status
2. RRC PDU Session Release: Refactor
rrc_gNB_process_NGAP_PDUSESSION_RELEASE_COMMAND
- Any PDU session in the pdusession_release_params list that is
present in the RRC list can be set to release, regardless of its
status
- Function Signature Update: Updated function signature and other
minor changes
- Response Handling: rrc_gNB_send_NGAP_PDUSESSION_RELEASE_RESPONSE is
sent upon completion of RRCReconfiguration
3. RRC PDU Session Release: add missing procedures E1AP Integration:
- Populates E1AP Bearer Modification for each to be released session
- PDCP Enhancement: Added nr_pdcp_release_drbs() to remove all DRBs
linked to a given PDU session in CUUP
- GTP-U Cleanup: GTP tunnel teardown handled in CUUP
e1_bearer_context_modif() using correct F1 or N3 GTP instance
4. NR PDCP/GTP:
- Enhanced Tunnel Deletion Logic: Separate handling for N3 tunnels (1
per PDU session) and F1-U tunnels (1 per DRB)
- New PDCP API Function: Added nr_pdcp_get_drb_ids_for_pdusession()
function to retrieve all DRB IDs associated with a specific PDU
session
5. RRC PDU Session Release: F1AP-based UE Context Modification:
- Replaced direct RRC message transfer with F1AP UE Context
Modification Request for proper retrieval from DU
- Cell Group Configuration: handling of updated CellGroupConfig from
DU ensures DRB release at CU
6. Docs and testing:
- Added PDU session add/remove test cases to 25 PRB RFSIM pipeline
- Documentation: Added PDU Session Release sequence diagram
- Telnet Commands: Added ci command to trigger NGAP PDU Session
Release and ciUE command to trigger establishment of a new PDU
Session
7. Additional fixes:
- UE RLC Management: ensure release of RLC entities
- Unify NG delay control before calling the RRC NGAP handler, for both
Setup and Release
8. Code Cleanup: Cleaned up unused GTP teardown functions.
Closes#867
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>
!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.
QFI 0 is a valid QFI: don't check for qfi <= 0, as uint8 cannot be
negative. Also, correctly use SDAP_MAP_RULE_EMPTY for a DRB ID (which
need to be larger than 0).
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
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.
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.
* Close entity->pdusession_sock manually before pthread_join() to unblock sdap_tun_read_thread()
* Update tun_destroy() to open a fresh socket for interface management, independent from the data socket
* Fix check on success of change_interface_state() in tun_destroy(): is a boolean
* Handle ENODEV error when bringing interface down: treat as success if the interface is already gone.
* tun_destroy() is now handling INTERFACE_DOWN, so `INTERFACE_DOWN` in `tun_config()` is no longer needed
sdap_tun_read_thread needs to know if we are gNB/UE. Previously, we
passed this into the thread, but the next commit also needs to for
interface termination, where this info is not available. So, for noS1
mode, pass this in.
This commit refactors the TUN interface management by moving its creation
and configuration from the PDCP layer to the SDAP layer for UE.
Key changes include:
- Introduced `tun_generate_ue_ifname` and `tun_destroy` functions for better
TUN interface lifecycle management.
- Added support for creating and destroying UE-specific TUN interfaces in SDAP.
- Refactored `nr_pdcp_module_init` to remove TUN-related logic and moved it
to SDAP.
- Updated NAS and SDAP layers to handle PDU session-specific TUN interface
creation and configuration.
- Enhanced SDAP entity management to include TUN socket handling and thread
lifecycle.
- Updated NAS message handling to initialize default PDU session TUN
interfaces in NOS1 mode.
- Use a single SDAP thread function for gNB and UE
- Allow noS1 mode also in SA on gNB
These changes improve modularity by isolating TUN interface management within
the SDAP layer, aligning with the 3GPP architecture, and simplifying the PDCP
layer.
Co-Authored-By: Robert Schmidt <robert.schmidt@openairinterface.org>
Using ITTI calls for user plane implies (1) a memory allocation, (2)
mutexes, and (3) queueing messages for each user plane packet, which is
heavy. Use a direct API call instead to reduce overhead.
