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>
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>
- 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.
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.
!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.
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
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>
- triggered by RRC reconfiguration events according to clause 5.3.5.6.5 of TS 38.331
- This procedure does QoS flow to DRB mapping according to clause 5.3.1 of TS 37.324
- QoS flows to DRBs to be released are also handled
remove several unused files
remove mem_block_t that is never used in a different way than a simple heap buffer
move up IP address type and remove duplications of the same struct declaration
There was a problem testing accelleran cu + oai du + oai ue + rfsim
because accelleran cu configures sdap header for UL but not for DL
and our sdap implementation deals with either "no sdap header at all"
or "sdap headers for both UL and DL".
The code has been modified to deal with the other cases
("sdap header for UL but not DL" and "sdap header for DL but not UL").
has_sdapDLheader and has_sdapULheader have been removed, has_sdap
too, replaced by has_sdap_rx and has_sdap_tx, which makes the code
independant of ue or gnb and is, I think, clearer.
With this work, accelleran cu + oai du + oai ue + rfsim works. We
also have oai gnb + oai ue + rfsim functional for all cases of sdap
header configuration (this won't happen for users, the code of gnb has to
be modified to have sdap header for only ul or only dl). It also works
with a COTS UE for all cases of sdap configuration (again, this won't
happen for users, only "no sdap header" and "sdap headers for both
UL and DL" exist in oai gnb with the current code).
To have other cases, you can edit openair2/RRC/NR/rrc_gNB_radio_bearers.c
and search for NR_SDAP_Config__sdap_HeaderDL_present in there.
To enable sdap, run the gnb with the command line argument
--gNBs.[0].enable_sdap 1
OAI is riddled with boolean_t, FALSE, TRUE, etc. This makes no sense, as
there is a standard bool type, and could lead to nasty bugs if a
definition of a bool is non-standard (0 == false, true == !false). This
commit removes all non-standard bools in the whole project.
1. Removed SDAP struct from protocol context.
2. Added configuration for the SDAP.
3. SDAP doesn't use pdcp_entities, the values come from function arguements.
4. Make nr_pdcp_ue_manager accessible from SDAP.
5. Avoid using the PDCP locking mechanism in SDAP.
6. Removed nr_pdcp_find_entity_sdap function.
7. Rename dummy eNB function to make GTP compile (no SDAP).
8. Fix: Regression issues with LTE
9. Fix: Regression issues with NR CU/DU
