- Use SRB0 TM entity at UE for Msg.3/RRC Setup Request
- Msg3 data request sent upon reception of Msg2, then we get data from
  rlc when needed

Most functions start with nr_rlc_*(), so do the same for release

- Add GOL-delay and AVG-soujour
- Correct the types of/measurement the tx/rxsdu_bytes and tx/rxsdu_occ_bytes
- Update txsdu_avg_time_to_tx value only when measurements activated
Co-authored-by: Teodora Vladic <teodora.vladic@openairinterface.org>

This commit repairs the reestablishment after the introduction of the CU
UE ID in the CU, different from the DU UE ID. Now, the CU uses an
identifier different from the RNTI, used in the MAC, to refer to UEs.

To repair the reestablishment, a number of changes needed to be
introduced:

- Handle old_gNB_DU_UE_id in MAC

The MAC handles the old_gNB_DU_UE_id field in the DL RRC Message. The
commit adds encoding/decoding of the field. The MAC will drop the old
UE, but retain the CellGroup of the corresponding UE(!). Because a UE
releases the spCellGroup on reestablishment, the MAC does the same; it
needs to reapply the old configuration after a reconfiguration. For the
latter, introduce new variables to keep a "future" CellGroupConfig to be
applied (reconfigCellGroup) and a flag (expect_reconfiguration) that
applies the CellGroupConfig if a DL RRC Message transfer on DCCH, which
is assumed to be the reconfiguration.

- Add RNTI change in RLC

The RLC needs to reuse the old UE context. Hence, we simply change the
RNTI in the old context, and delete the new one.

- No PDCP UE ID change

The previous implementation of the PDCP used the RNTI; hence, the ID
needed to be switch (as above for the RLC). Since the PDCP now also uses
the CU UE ID, no identifier change is needed, and we remove all
corresponding code.

- No MAC modifications/update from CU

As foreseen by the spec, the CU does not modify or change the
cellGroupConfig in the RRC during reestablishment. This change will be
generalized in the future to all of the RRC.  Also, the
nr_rrc_mac_remove_ue() function has been removed: the MAC handles any UE
changes autonomeously, without being triggered from the RRC explicitly.

- Remove reestablish_rnti_map

The RRC does not use RNTIs for UE identification. Hence, a
reestablish_rnti_map to link two UEs to each other is not necessary
anymore.

Plugin can trigger reestablishment (on DU)
and show counters of reestablishment (on CU)

For nr_DRB_preconfiguration() and fill_default_secondaryCellGroup(),
there is duplicated code to generate and RLC-BearerConfig, when calling
the existing get_DRB_RLC_BearerConfig() (with the right parameters)
yields a similar configuration (see exceptions below).

Differences:
- We do not support reestablishmentRLC, so we don't set it
- Set prioritisedBitrate to 8kbps instead of infinity (we don't
  prioritize anything, anyway)
- bucketSizeDuration is 50ms instead of 100ms

Creates function that have nr_pdcp_ prepended to their name, and change
the signature of some functions for the 5G PDCP:

- nr_pdcp_layer_init()
- nr_pdcp_data_req()
- nr_pdcp_remove_UE()
- nr_pdcp_config_set_security()
- nr_pdcp_remove_UE()
- Make separate functions for nr_pdcp_data_req_srb/drb()

During the Initial UL RRC Message, the CellGroup is created. Since the
CellGroup specifies the SRB1, the SRB1 should also be created (because
the DL RRC Messages is sent via SRB1). However, before this commit, the
CellGroup is created while having the RLC lock, so we cannot create
SRB1, as it results in a deadlock.

Therefore, we now first create CellGroup, SRB0, and SRB1, before giving
the UE message to the RLC.

With contributions from
* Sakthivel Velumani <velumani@eurecom.fr>
* Robert Schmidt <robert.schmidt@openairinterface.org>

Squashed commit of the following:

commit e8488acb
Merge: f09468eb 5d58645a
Author: laurent <laurent Thomas>
Date:   Sat Jan 21 15:03:40 2023 +0100

    merge develop

commit f09468eb
Author: laurent <laurent Thomas>
Date:   Fri Jan 20 10:43:51 2023 +0100

    continue e1AP development

commit 76545cfb
Author: laurent <laurent Thomas>
Date:   Wed Jan 18 14:18:47 2023 +0100

    fix regressions after merge develop

commit 7071c480
Merge: 569b9fc5 214aa505
Author: laurent <laurent Thomas>
Date:   Mon Jan 16 15:51:50 2023 +0100

    merge develop

commit 569b9fc5
Author: laurent <laurent Thomas>
Date:   Wed Jan 4 17:07:01 2023 +0100

    fix srb2 addition, simplify and remove dead code, fix one race

commit 9fa89151
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Wed Jan 4 20:02:05 2023 +0530

    Bearer context release decoder and encoder

commit 7011cb51
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Wed Jan 4 13:43:58 2023 +0530

    Update documentation

commit 3e8899fc
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Wed Jan 4 10:14:11 2023 +0530

    Fix function arguments and warnings

commit 989ad183
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Jan 3 20:18:31 2023 +0530

    Moved E1-design.md to doc/

commit 04a8633d
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Jan 3 20:13:46 2023 +0530

    Make libraries lower case in CMakeLists

commit 033ec174
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Jan 3 17:55:25 2023 +0530

    Renamed and updated cucp cuup config files

commit f76a6913
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Jan 3 13:31:19 2023 +0530

    Removed CU-UP checks from nr-softmodem

commit ae70afe4
Author: laurent <laurent Thomas>
Date:   Mon Jan 2 13:01:45 2023 +0100

    fix for gcc version hat doesnt accept declarations in switch

commit 6a7a0104
Author: laurent <laurent Thomas>
Date:   Tue Dec 27 15:59:28 2022 +0100

    first functional commit standalone cu-up

commit 0caa4690
Merge: 3619f955 1a0c0cd1
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Fri Dec 23 14:21:00 2022 +0530

    Merge remote-tracking branch 'origin/develop' into e1-implementation-wip

commit 3619f955
Merge: 1bcf8d5e cfe698eb
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Wed Dec 21 15:47:40 2022 +0530

    Merge remote-tracking branch 'origin/develop' into e1-implementation-wip

commit 1bcf8d5e
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Sep 13 02:10:34 2022 -0400

    Fix GTP rnti to ue_id after rebase

commit 23075ff8
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Sep 6 00:32:12 2022 -0400

    Added documentation

commit 28f6e507
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Mon Sep 5 15:02:02 2022 -0400

    Header cleaups and unitary simulators build fixes

commit e665dbab
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Thu Sep 1 17:52:07 2022 -0400

    Common interface between CUCP & CUUP for E1 and non E1 modes

commit 5dcc1bf5
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Thu Sep 1 13:53:49 2022 -0400

    Allocate stack where ever possible
    Free memory after ASN encode

commit 793a5379
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Thu Sep 1 10:41:50 2022 -0400

    Fixes for build issues

commit 0d3564f2
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Wed Aug 31 20:57:14 2022 -0400

    Fixed uesoftmodem linkage error

commit 34adf865
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Wed Aug 31 19:31:50 2022 -0400

    Removed RRC thread from CUUP

commit 53674191
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Wed Aug 31 14:21:31 2022 -0400

    Add header guard in one of E1AP header

commit 22e9d9b6
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Wed Aug 31 14:00:47 2022 -0400

    Fix bug in PDCP ue_id

commit 4c65339b
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Aug 30 18:04:59 2022 -0400

    Linked E1AP lib to L2_NR target
    E1AP builds for nr-softmodem

commit 014fe30a
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Aug 30 15:49:27 2022 -0400

    Remove xer prints from e1ap
    and gcc warning fixes

commit 71f0c912
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Aug 30 15:42:30 2022 -0400

    Fixed bug in integrity protection config

commit 4e393ef9
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Aug 30 14:34:37 2022 -0400

    GTP init with only local address
    IP traffic works both directions in Mono, F1 and E1

commit ec3bde2c
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Aug 30 00:16:03 2022 -0400

    Fix bug in pdcp config and GTP instance
    UL iperf still not works. Can see packets in wireshark.

commit be8df443
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Sat Aug 27 20:15:04 2022 -0400

    Fixes in node config after rebase

commit 6f42ff88
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Sat Aug 27 01:38:21 2022 -0400

    Added N3 tunnel address in config params
    fixed bug in address length feild

commit b5e13204
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Fri Aug 26 20:38:47 2022 -0400

    Send UL UP address via F1 UE cxt mod msg

commit ecfd0fe2
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Fri Aug 26 15:08:53 2022 -0400

    Update GTP remote address from response message
    Modified GTP tunnel update function accordingly
    Put GTP tunnel update out of F1AP
    F1 split works

commit 14a37e41
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Sat Aug 20 01:17:36 2022 -0400

    Moved GTP tunnel creation out of F1AP message sending

commit cdd58ab9
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Fri Aug 19 17:40:43 2022 -0400

    Moved DRB config out of RRCReconfig complete
    Monolithic and F1 split works

commit 61d66e49
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Thu Aug 11 01:30:10 2022 -0400

    Allow CUUP to have RRC inst without error

commit dd7ae889
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Thu Aug 11 01:29:21 2022 -0400

    Added missing IEs in bearer cxt response handler

commit a6f1fe5f
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Wed Aug 10 21:02:30 2022 -0400

    Unified bearer context message transfer for E1 and non-E1 mode
    compiles, to be tested

commit f245ace2
Author: laurent <laurent Thomas>
Date:   Tue Aug 9 17:46:52 2022 +0200

    remove log_i() of fatal errors

commit d2a0f3c8
Author: laurent <laurent Thomas>
Date:   Fri Aug 5 15:01:39 2022 +0200

    fix rnti/ue_id for ue

commit 7b52c6cd
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Thu Aug 4 19:14:46 2022 -0400

    Created separate functions in PDCP for E1 mode

commit 46680d2b
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Thu Aug 4 19:13:10 2022 -0400

    Bug fixes in bearer context setup response

commit 3d091bfd
Author: laurent <laurent Thomas>
Date:   Thu Aug 4 15:42:11 2022 +0200

    add missing file from previous commit

commit 21838572
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Wed Aug 3 16:59:16 2022 -0400

    Minor bug fixes

commit 34eb73fb
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Aug 2 23:16:47 2022 -0400

    Added config files for testing
    To be renamed or removed later

commit a7e9c6fb
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Aug 2 23:15:21 2022 -0400

    Made rrc_gNB_get_ue_context_from_ngap_ids() non static

commit 028f0407
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Aug 2 23:12:16 2022 -0400

    Completed bearer context setup cycle
    To be tested: Handling of bearer context setup response and subsequent UE context modifition msg to F1AP task

commit 4481d113
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Aug 2 23:01:50 2022 -0400

    Fixed E1AP PPID (wireshark fixed)

commit 7a22573f
Author: laurent <laurent Thomas>
Date:   Fri Jul 29 13:03:31 2022 +0200

    fix compile issues, simplify gtp send function

commit 0209011a
Author: laurent <laurent Thomas>
Date:   Thu Jul 28 11:51:18 2022 +0200

    restore compilation capability, gtp replacement of rnti by ueid

commit ce3b886f
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Fri Jul 22 08:35:31 2022 -0400

    Included missing IEs in bearer cxt setup message

commit 1208ae0d
Author: Cedric Roux <cedric.roux@eurecom.fr>
Date:   Tue Jul 19 10:53:35 2022 +0200

    replace rnti by ue_id in pdcp

    some sdap and gtp files had to be touched, the work is not finished in there

    some changes in nr_pdcp_oai_api.c simply assume ue_id is indeed rnti
    (will functions in this file be used by cu-up?)

commit e67d1c88
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Jul 19 10:08:39 2022 +0200

    Replace RNTI with UE ID in GTP files
    (half done. Laurent to change ctxt_t)

commit 7a141e8e
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Jul 19 10:04:15 2022 +0200

    Added RRC handler for bearer cxt setup in CUUP

commit fe210667
Author: laurent <laurent Thomas>
Date:   Mon Jul 11 13:30:30 2022 +0200

    fix race in startup procedure (config before starting threads that use the config)

commit 3197baab
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Sun Jul 10 11:30:31 2022 +0200

    Fixed bugs in bearer creation

commit 26be6116
Author: laurent <laurent Thomas>
Date:   Sun Jul 10 10:50:57 2022 +0200

    fix a race, add asn1c debug method

commit 26750d18
Author: laurent <laurent Thomas>
Date:   Wed Jul 6 22:34:10 2022 +0200

    e1ap bearer setup encoding invalid

commit d092788a
Author: laurent <laurent Thomas>
Date:   Wed Jul 6 14:18:39 2022 +0200

    fix regression with F1, some basic cleaning in NGAP

commit 41a13573
Author: laurent <laurent Thomas>
Date:   Wed Jul 6 11:24:52 2022 +0200

    fix some ngap regressions

commit 460acd84
Author: laurent <laurent Thomas>
Date:   Tue Jul 5 21:19:13 2022 +0200

    build, run in F1 mode until UE connect but pdu session still fails

commit 7c067095
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Sat Jun 25 22:45:46 2022 +0530

    Populate PDU and DRB paramenters from NGAP

commit c4ada56a
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue Jun 7 22:16:58 2022 +0530

    setup resp decoding success

commit a2f41597
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Sat Jun 4 13:50:55 2022 +0530

    Fixed bugs in E1 setup procedure
    E1 setup request decoding successful

commit 6106207b
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Thu May 26 20:13:14 2022 +0530

    Fixing build issues

commit 67235fac
Author: Robert Schmidt <robert.schmidt@openairinterface.org>
Date:   Mon May 23 12:04:22 2022 +0200

    Make nr-softmodem depend on E1AP module

commit 391cee93
Author: Robert Schmidt <robert.schmidt@openairinterface.org>
Date:   Mon May 23 11:57:15 2022 +0200

    Fix ITTI errors in E1AP target

commit db4146e4
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Wed May 18 06:59:03 2022 +0530

    CP UP task created

commit 3058d2fc
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue May 10 08:12:19 2022 +0530

    Bearer context setup response message

commit b911e9db
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Tue May 3 16:52:49 2022 +0530

    Bearer context setup c structs

commit d0f4d5f3
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Thu Apr 28 02:21:50 2022 +0530

    Bearer context setup message

commit 489a5358
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Thu Apr 21 10:11:03 2022 +0530

    Started with CUUP task

commit b416061f
Author: Sakthivel Velumani <velumani@eurecom.fr>
Date:   Fri Apr 15 18:46:27 2022 +0530

    Setup request and response messages

commit faca4b97
Author: Robert Schmidt <robert.schmidt@openairinterface.org>
Date:   Mon Apr 11 15:01:48 2022 +0200

    Fixup for cmake execution

commit ecfd9f76
Author: Robert Schmidt <robert.schmidt@eurecom.fr>
Date:   Tue Nov 24 21:39:20 2020 +0100

    Move CMakeLists.txt into root

commit 9f41f7c5
Author: Robert Schmidt <robert.schmidt@openairinterface.org>
Date:   Tue Apr 12 12:07:18 2022 +0200

    Remove hwlat refs in build_oai: targets don't exist anymore

commit e666cf5e
Author: Robert Schmidt <robert.schmidt@openairinterface.org>
Date:   Mon Apr 11 14:37:32 2022 +0200

    Create CMake E1AP_RELEASE variable from E1AP_VERSION

commit 1f841336
Author: Robert Schmidt <robert.schmidt@openairinterface.org>
Date:   Sun Apr 10 14:25:38 2022 +0200

    Add E1AP lib

commit 7465cea4
Author: Robert Schmidt <robert.schmidt@openairinterface.org>
Date:   Sun Apr 10 14:48:40 2022 +0200

    Add E1AP Grammar and build ASN.1 lib at build time

commit cde22f83
Author: Robert Schmidt <robert.schmidt@openairinterface.org>
Date:   Fri Apr 22 13:42:51 2022 +0200

    Accept higher vers. nums in make_version/MAKE_VERSION

commit d5127b23
Author: Robert Schmidt <robert.schmidt@eurecom.fr>
Date:   Tue Nov 24 21:39:20 2020 +0100

    Move CMakeLists.txt into root

ASN_SEQUENCE_ADD return code was checked only in 0.5% of calls, existing errors not detected by sanitize address

- new definition to replace hardcoded values

- AssertFatal() in nr_rlc_srb0_recv_sdu() if the srb0 is not found
- do_RRCSetup() may return -1, handle it properly
- do_RRCReject() may return -1, handle it properly
- remove one switch in rrc_gNB_generate_RRCReject()

Introduce the function nr_rlc_activate_avg_time_to_tx() to
activate/deactivate collection of avg time to tx stats (which
may have an impact on realtime processing, so better not compute
them when not needed).

Fix a little bug in time_average_get_average() for when there is not stat.