This commit introduces the NG Mobility Management Procedure known as
Handover Resource Allocation. The inbound message is sent by the AMF
and is known as Handover Request.
Major changes:
(0) Add Handover Resource Allocation initiating message decoding
* add case for NGAP initiating message and unsuccessful message decoding
(1) handle Handover Request on the target NG-RAN
(2) decode NG Handover Request message
(3) process payload, e.g. create UE context,
store IDs, set UP security and trigger bearer setup
Co-authored-by: batuhan duyuler <batuhan.duyuler@firecell.io>
This message is sent from the Target NG-RAN to the AMF.
The commit introduces:
* NGAP encoding function
* N2 callback for the target gNB
* handle the failure in RRC, inform NGAP
* send NGAP message to AMF via SCTP
Note: UE context in NGAP is fetched from the amf_ue_ngap_id
Co-authored-by: batuhan duyuler <batuhan.duyuler@firecell.io>
(1) add N2 ho decision based on measurements
(2) add trigger for N2 HO on source CU
(3) generate NG Handover Preparation Information message,
including RRCReconfiguration, to be passed to the
NG Handover Required message
(4) call RRC callback for Handover Required message
Co-authored-by: batuhan duyuler <batuhan.duyuler@firecell.io>
This commit introduces the NG Mobility Management Procedure known as
Handover Preparation. The outbound message is sent by the source NG-RAN
and is known as Handover Required.
* introduce NGAP library for Mobility Management
* introduce NGAP IEs encoder functions for Handover Required and relevant common IEs
* handle RRC trigger in NGAP and Send NGAP Handover Required to the AMF
Co-authored-by: batuhan duyuler <batuhan.duyuler@firecell.io>
During the N2 HO review has been found that the HO context
was not allocated at trigger time but later in the flow. This
might lead to issues in some scenarios (e.g. in N2 HO)
and it was fixed in this commit.
During the review of the N2 HO MR it has been found that the wrong type
plmn_identity_t (S1AP) was used in RRC. Now updated to the platform type plmn_id_t.
Refactor measConfig
- Refactor and minor improvements in get_MeasConfig function;
- Add support for band in neighbourConfiguration (It is currently
possible to handover cells with different frequencies, as long as they
are in the same band, but this MR allows the handover to also be done
between cells in different bands).
- Replaced ITTI message queues with notifiedFIFO for RRC to MAC communication in UE.
- Enables correct message delivery to multiple MAC instances running in parallel threads.
- Introduced `nr_mac_rrc_message_t` union for MAC-RRC messages.
- Updated all relevant message handling and initialization code to use notifiedFIFO.
Use MAX_NUM_NR_UE_INST for number of NR UE RRC instances. Change the RRC
interface slightly so nr_rrc_init_ue initializes only one RRC instance pointed
to by the id given to the function
Interoperability testing with srsRAN DU shows than when receiving
RRCReconfigurationCompleteIndicator in a UEContextModificationRequest
the DU replies in the UEContextModificationResponse with an empty
CellGroupConfig.
This CellGroupConfig is encoded as 2 zero bytes. Let's ignore this
message when we receive it, don't forward it to the UE in a
RRC Reconfiguration, as it should per standard (38.473 8.3.4.2):
If the CellGroupConfig IE is included in the DU to CU RRC Information
IE contained in the UE CONTEXT MODIFICATION RESPONSE message, the
gNB-CU shall perform RRC Reconfiguration as described in TS 38.331 [8].
The CellGroupConfig IE shall transparently be signaled to the UE as
specified in TS 38.331 [8].
To be removed/reworked in the future if the interoperability
situation improves.
Add a CU-UP load tester and improve GTP performance
This adds a simple tester program for the CU-UP. It sets up a number of
UEs/bearers in the CU-UP via the E1 interface, then streams data in
downlink/uplink (as seen by the CU-UP). More information is available in
tests/nr-cuup/README.md.
Includes some fixes to properly verify that SCTP is installed, and use
"the right cmake way" to use it in cmake code (see commit for details).
remove specific directory for LTE SIM management tools
This is very old code has never been integrated with the "main" OAI
cmake infrastructure and more recent libraries.
This MR integrates the three binaries for LTE virtual sim management in
the regular build process and log system
Remove the --usim-test option: to my knowledge, it's not used by users,
and is misleadingly placed in various places where there should not be a
difference w.r.t. USIM configuration.
When making the changes, I assumed that --usim-test would be 0 (the
default), which is the case in all executables when not specified in
options except for the nr_dlsim, nr_pbchsmi, nr_ulsim simulators.
The only exception is the initialization of PDCP from the MAC, which is
not correct (the PDCP is in the CU, so it does not make sense to call it
from the MAC which is in the DU). Instead, always initialize from main,
even in the NSA case (NSA was covered by the incorrect initialization
from MAC).
This in turn let to some more cleanup around function du_rlc_data_req().
After receiving GTP packets at the DU, they were given to the PDCP to
enqueue the packet at RLC. This does not work anymore, since the PDCP is
not initialized; it also does not seem necessary, as this enqueue
functionality is necessary to decouple PDCP and RLC to avoid deadlocks
in monolithic, but in split-mode, this cannot happen. Instead, call
directly into the RLC when receiving GTP packets.
Measurement gaps
Scheduling measurement gaps to provide sufficient time for the UE to
re-tune its transceiver to the target carrier, complete the set of
measurements and then re-tune its transceiver back to the original
carrier.
Add WLS as a transport option for VNF/PNF, refactor existing options
This MR adds a new transport mechanism for the VNF and PNF split, using
the Intel WLS library, which makes use of DPDK and shared memory to
transport messages. This transport mechanism is what is used to
interface with Radisys ODU, while also working with OAI VNF/PNF.
The VNF and PNF have been refactored so that the transport-specific
functions are isolated from the rest of the logic, and as such,
interchangeable by means of function pointers.
The same change is done for the packing/unpacking procedures, allowing
to switch between FAPI and nFAPI encoding.
This MR also reduces the amount of duplicated code, by refactoring the
VNF with Aerial, which now only has the transport-relevant functions, as
well as the ones that are unique to it ( for example, the unpacking
procedures where a secondary data buffer is used for the message
payloads )
Additionally a new callback is added to the VNF to process
ERROR.indication messages, which currently only indicates which message
originated the error, and which error occurred.
The changes done in this commit are to contribute the supporting changes
for the existing "Initial support for RedCap" feature in gNB.
In this patch, handle and store the RedCap related IE's present in "NR
UE Capability Information" msg which are
- 'supportOfRedCap-r17'
- 'supportOf16DRB-RedCap-r17'
- 'longSN-RedCap-r17'
- 'am-WithLongSN-RedCap-r17'
use 'longSN-RedCap-r17' and 'am-WithLongSN-RedCap-r17' IEs to set the SN
length to either 12 Bit or 18 Bit accordingly.
Previously, we only supported intra-frequency handovers, so the
measurements where only for intra-frequency, reusing the same
measurement object. Now that we would support inter-frequency handover,
also add multiple MeasObjects for each neighbor.
bugfix: UE AMBR is optional
This was a problem with open5gs and more than one PDU session. The core network
sets UE AMBR only once, leading to failure in the gNB for the second PDU session.
(A proper handling of AMBR has to be develop at some point in the gNB.)
This was a problem with open5gs and more than one PDU session.
The core network sets UE AMBR only once, leading to failure in the gNB
for the second PDU session.
(A proper handling of AMBR has to be develop at some point in the gNB.)
continuously update SIB19 information for rfsim NTN LEO scenarios
Contains mainly these changes:
- gNB: add function nr_update_sib19() allowing to update SIB19
information
- rfsimulator: update SIB19 contents every frame for LEO channel
simulations
- NR UE: improve initial timing advance calculation from SIB19
Before, we only considered ta_Common_r17 and the SAT position from SIB19
to compute the initial timing advance value. This is good enough if the
satellite does not move too fast (e.g. GEO satellite).
Now we also consider ta_CommonDrift_r17, ta_CommonDriftVariant_r17 and
the SAT velocity together with the epoch time from SIB19. This improves
the accuracy of the initial TA computation, esp. for LEO satellite
scenarios.
Various fixes for UE handling, HO doc updates
- On release request, search both attach and connected list to free a UE.
- on DU disconnect, only release the correspnonding UE contexts.
- When no AMF for the UE, auto-release the UE (NGAP would also send an
answer, but better check first)
- implement a "grace period" before the DU/MAC automatically releases a
UE: this is to avoid cases in which (for whatever reason) the UE
release request is not honored by the CU. In order to not fill up UE
contexts unnecessarily, the DU will eventually (after 10s) drop the UE
context
- some clarification in HO tutorial
Mark non-existing AMF UE NGAP ID through invalid INT64_MAX number
(permitted range is up to 2^40-1). Check for this range in the RAN
function, as we might otherwise pass the invalid AMF UE NGAP ID to the
agent, which would assert with
nr-softmodem: /oai-ran/openair2/E2AP/flexric/src/lib/3gpp/enc/enc_gnb.c:83: enc_gNB_UE_asn: Assertion `gnb->amf_ue_ngap_id < 1UL << 40' failed.
In other words, don't send KPM messages for a UE which has no valid AMF
UE NGAP ID yet (which follows from the fact that the spec requires an
AMF UE NGAP ID; the previous behavior of simply sending 0 could be
considered a bug, because it's not the UE's true AMF UE NGAP ID).
NR RRC Reject UE
Improvements in procedures to handle RRCReject message both at gNB and
UE. At gNB we send RRC Reject if the UE cannot be given resources to go
into connected mode.
Direct leak of 512 byte(s) in 1 object(s) allocated from:
#0 0x7f37634e5e2b in realloc.part.0 (/lib64/libasan.so.8+0xe5e2b) (BuildId: 7f1aa7e2e600e8c9d54ce6e3d36f3d31bfe7949a)
#1 0x000000fbb9ad in encode_dyn_cb /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/per_encoder.c:23
#2 0x000000fc279e in asn_put_few_bits /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/asn_bit_data.c:220
#3 0x000000fc279e in asn_put_few_bits /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/asn_bit_data.c:192
#4 0x000000fc2ce5 in asn_put_many_bits /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/asn_bit_data.c:293
#5 0x000000fb8c33 in OCTET_STRING_encode_uper /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/OCTET_STRING_uper.c:306
#6 0x000000fd191a in SEQUENCE_encode_uper /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/constr_SEQUENCE_uper.c:403
#7 0x000000fd191a in SEQUENCE_encode_uper /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/constr_SEQUENCE_uper.c:403
#8 0x000000fcb140 in CHOICE_encode_uper /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/constr_CHOICE_uper.c:177
#9 0x000000fd191a in SEQUENCE_encode_uper /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/constr_SEQUENCE_uper.c:403
#10 0x000000fcb140 in CHOICE_encode_uper /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/constr_CHOICE_uper.c:177
#11 0x000000fcb140 in CHOICE_encode_uper /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/constr_CHOICE_uper.c:177
#12 0x000000fd191a in SEQUENCE_encode_uper /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/constr_SEQUENCE_uper.c:403
#13 0x000000fbc1ed in uper_encode /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/uper_encoder.c:27
#14 0x000000fbc73a in uper_encode_to_new_buffer /home/richie/w/f1-refactor-ue-context/build/openair2/RRC/LTE/MESSAGES/uper_encoder.c:85
#15 0x000000e10fbd in do_RRCReconfiguration /home/richie/w/f1-refactor-ue-context/openair2/RRC/NR/MESSAGES/asn1_msg.c:586
#16 0x000000805712 in rrc_gNB_encode_RRCReconfiguration /home/richie/w/f1-refactor-ue-context/openair2/RRC/NR/rrc_gNB.c:652
#17 0x000000893860 in nr_rrc_f1_ho_acknowledge /home/richie/w/f1-refactor-ue-context/openair2/RRC/NR/rrc_gNB_mobility.c:280
#18 0x0000008079ac in rrc_CU_process_ue_context_setup_response /home/richie/w/f1-refactor-ue-context/openair2/RRC/NR/rrc_gNB.c:2139
#19 0x0000008330d8 in rrc_gnb_task /home/richie/w/f1-refactor-ue-context/openair2/RRC/NR/rrc_gNB.c:2771
#20 0x7f3763428ee5 in asan_thread_start(void*) (/lib64/libasan.so.8+0x28ee5) (BuildId: 7f1aa7e2e600e8c9d54ce6e3d36f3d31bfe7949a)
During refactoring, I had asan errors in the next line. It took me some
time to figure out that a DRB ID 0 is not valid (cf.
get_next_available_drb_id() and get_drb(), they enforce this).
Direct leak of 48 byte(s) in 1 object(s) allocated from:
#0 0x7fea71ee6f0b in malloc (/lib64/libasan.so.8+0xe6f0b) (BuildId: 7f1aa7e2e600e8c9d54ce6e3d36f3d31bfe7949a)
#1 0x0000007f29c0 in malloc_or_fail /home/richie/w/f1-refactor-ue-context/common/utils/utils.h:86
#2 0x0000007f29c0 in cuup_notify_reestablishment /home/richie/w/f1-refactor-ue-context/openair2/RRC/NR/rrc_gNB.c:872
#3 0x000000808002 in rrc_CU_process_ue_context_setup_response /home/richie/w/f1-refactor-ue-context/openair2/RRC/NR/rrc_gNB.c:2126
#4 0x0000008330d8 in rrc_gnb_task /home/richie/w/f1-refactor-ue-context/openair2/RRC/NR/rrc_gNB.c:2770
#5 0x7fea71e28ee5 in asan_thread_start(void*) (/lib64/libasan.so.8+0x28ee5) (BuildId: 7f1aa7e2e600e8c9d54ce6e3d36f3d31bfe7949a)
