The F1AP UE context release procedure can happen in at least two cases:
1. core requested a release of a UE
2. CU requests DU a release of a UE without a core release (e.g.,
handover)
In case 1., the CU has to fully release the UE in the CU, then ack the
NGAP message from the core, whilst in 2., nothing of that should happen
after the DU acknowledges the F1AP UE context release cmd.
cuup_notify_reestablishment() used
&ue_p->established_drbs[drb_id]
to look up a bearer, which is wrong, because it should be drb_id - 1
as in the top of the loop. Also, it used the dedicated get_drb()
function; harmonize to use only this function.
A follow-up commit refactors the filling of information of DRBs to set
up in a separate function (to be reused for handover later). Hence, we
cannot store the DRB TEID/address in the same functions, because it is
a logically separate step, and might not always be available.
In e1_send_bearer_updates(), we send the DL (DU) TEID and address to the
CU-UP. Therefore, correct the variable names to reflect that the F1-U
information pertains to the DU.
Also, move the tunnel info update function f1u_dl_gtp_update() to a more
prominent place, and take the pointer to the struct containing the
"interesting" information.
A maximum RRC buffer size of 1024 might be very small. We should
increase it, but then the 5G RRC_BUF_SIZE does conflict with other
definitions. To make it unique, also rename to NR_RRC_BUF_SIZE.
Pass consistently the NR_timer_t object through a pointer. Since we have
to modify all occurrences of is_nr_timer_active(), we use that occasion
and rename that function to nr_timer_is_active() to make it consistent
with all other functions, starting with nr_timer.
Reorganize the sequence of checks done in reestablishment to make it
more logical:
- check conditions of request (correct C-RNTI)
- check conditions of DU (has MIB/SIB1, MTC)
- check the UE, and from which DU it comes
This will also help to extend it towards reestablishment coming from
different DUs in the case of handover.
Before this bug fix, when using F1, we get this warning:
Constraint validation failed: LCID: constraint failed (/home/richie/openairinterface5g/cmake_targets/ran_build/build/openair2/F1AP/MESSAGES/F1AP_LCID.c:30)
This is because (1) we don't actually store the LCID, then (2) we did
not put it into the F1 ASN.1 structures. Fix both, to make this warning
disappear.
To actually print the full error message, increase the error buffer
size. Also, for the future, to avoid guessing, print ASN.1 XML when we
encounter a failed constraint validation.
It can happen that SCTP communication is simply lost, e.g.
[SCTP] SCTP_ASSOC_CHANGE to SCTP_COMM_LOST
[SCTP] sctp_recvmsg (fd 104, len -1 ): Connection reset by peer:104
The previous code only handled the SHUTDOWN event, but in abnormal
situations, we should also handle the connection state change and signal
to RRC that the endpoint is dead, which is now implemented.
User of the SCTP module use the assoc_id for connection identification.
The previous code set the assoc_id to -1, so there is no way of telling
which connection broke. Use the assoc_id instead
The failure mode observed here was that the CU sent a release command
for a UE that the DU does not know. Given, that the outcome of the
release command (no UE) is equal to the current state (no UE), from
the DU point of view, we can safely ack the command.
At least in Eurecom, there are no RHEL 7/CentOS 7+8 servers. Existing
installations will work, but we don't want to encourage people to use
these old distributions, so remove it. Also, they reached EOL
Add CentOS stream as an alternative.
In the past, it seemed that we had to add a trailing slash (/) after the
OpenShift Registry URI. Now, at least on the CI machine matix, this
makes it fail:
INFO: oc whoami -t | docker login -u oaicicd --password-stdin default-route-openshift-image-registry.apps.oai.cs.eurecom.fr/
INFO: docker pull default-route-openshift-image-registry.apps.oai.cs.eurecom.fr/oaicicd-ran/oai-gnb:develop-46a1d2a6
WARNING: command "docker pull default-route-openshift-image-registry.apps.oai.cs.eurecom.fr/oaicicd-ran/oai-gnb:develop-46a1d2a6" returned non-zero returncode 1: output:
Error response from daemon: Head "https://default-route-openshift-image-registry.apps.oai.cs.eurecom.fr/v2/oaicicd-ran/oai-gnb/manifests/develop-46a1d2a6": unauthorized: authentication required
Remove the trailing slash makes it work, like so:
INFO: oc whoami -t | docker login -u oaicicd --password-stdin default-route-openshift-image-registry.apps.oai.cs.eurecom.fr
INFO: docker pull default-route-openshift-image-registry.apps.oai.cs.eurecom.fr/oaicicd-ran/oai-gnb:develop-46a1d2a6
The docker pull succeeds.
Before this commit, the following will trigger a complete rebuild:
- create another git name (git checkout -b test)
- run cmake again manually (cmake ..)
- run ninja again
The top-level CMakeLists.txt uses add_definitions() to add git
information to all targets; if some git information changes, this will
mark all command lines as dirty, triggering the build.
There is an easy solution: instead of passing this information on the
command line, pass it in a header. This commit uses configure_file() to
generate a file oai_version.h in the build directory with the same
information. Various sources files, e.g., main executables, use this to
output the same information as before. It is then also not necessary to
use header guards, as cmake takes care to create this file.
If cmake is re-run, it will update the header, and trigger only files
including this header will be rebuilt (which can be shown with the above
stpes). The information passed is the same as before, and updates the
information when the old method would have updated it.
The correct order for xran seems to be first Uplane, then C plane. In
the past, we used to switch (for reasons I don't know), but let's
reverse it to the proper order.
Handle IPv6 (and IPv4v6) PDU sessions by correctly instructing
nas_config() to set up the interface with provided IP addresses.
Note that as of now, IPv6 PDU sessions have not been fully tested.
Remove a useless assert at the gNB; to my understanding the gNB does not
care about the IP session type (at least for IP), as it just
transparently tunnels the IP packets from/to GTP.
I added a comment in the code where to change to request a PDU session
different from IPv4. Currently it is hardcoded to IPv4, and it seems
that a default OAI 5GC config would reject a PDU session type different
from IPv4.
- Read interface flags before setting status to not inadvertently
overwrite existing flags
- Set interface flag point-to-point, remove multicast (I think a UE is
not supposed to send anywhere else than to the UPF, so it seems to not
make sense to declare the interface as multicast)
These rules & route are necessary to properly send packets on oaitun_ue1
interface:
1. This forces the packets coming from a subnet different than the UE's
subnet to go back through oaitun_ue1 rather than via what the default
route defined on the system (e.g., important if ping from the
internet arrives).
2. On machines setting net.ipv4.conf.oaitun_ue1.rp_filter=1 (e.g.
RHEL), this prevents that source filtering for packets coming back is
applied and those packets be dropped. By default, many hosts have
rp_filter=2, so no strict source filtering is applied, and it would
work; on others, this rule prevents source filter dropping.
Prior to this commit, there was a global variable baseNetAddress that
could be set independently through a setter and also through the
configuration module. This baseNetAddress (16 bits IPv4) would then be
complemented with two more bytes in nas_config().
However, this is counter-productive, as not only we have a global
variable that is avoidable (we can give the entire address to
nas_config() directly), but it also would not work with IPv6. Hence,
modify to give nas_config() the entire address. A follow-up commit will
add IPv6 support.
- refactor functions to make them shorter
- provide doxygen strings
- open socket for operation once instead of in each function
- use named constant (from enum) to differentiate interface UP/DOWN
- Linux kernel defines name length as IFNAM_SIZE, so use that for
interface name length. Also, it seems no null-byte is needed.
I initially planned to entirely remove the netmask configuration.
However, in specific configurations, e.g. in 4G Rfsim with feMBMS,
routing does not seem to work anymore using these commands:
iperf -B 10.0.2.2 -s -u -i1
iperf -c 10.0.2.2 -B 10.0.2.1 -u -t 30 -b 2.00M -i1
Therefore, we simplify by hardcoding the netmask to /24, which allows
the above to work.
Remove the broadcast address from the UE, as logically, a UE has nothing
to broadcast: it can only directly talk to the core. Additionally, at
least as of now, the UE interface is shown as "POINTOPOINT", so
broadcasting is not possible.
Does the same change in the _mbms() functions as in the previous commit.
Also, simplify logic in netlink_init_mbms_tun(): directly use the id in
the interface. This requires a slight ID change in the users, which is
also done in this commit.
Instead of implicitly using a hardcoded prefix "oaitun_" interface
name, move that out to the callers of these functions to make it clear.
The ID still remains outside.
The "sister functions" nas_config_mbms()/netlink_init_tun_mbms() will do
the same change in the next commit.
Comparing both functions, it seems that nas_config_mbms_s1() sets the
same parameters, assuming that in nas_config_mbms(), we set
- (UE_NAS_USE_TUN || ENB_NAS_USE_TUN) yielding true -> should yield the
same interface name
- netmask is hardcoded to 255.255.255.0
- baseNetAddress is hardcoded 10.0
So replace the call with nas_config_mbms() by setting parameters
accordingly.
- Remove unused NAS_config(): It does most of what the highly similar
nas_config() does.
- Remove unused set_gateway()
- Remove unused blocking_NAS_config()
- Remove unused functions getNetMask()
- Remove unused broadcast functionality: functions setBroadcastAddress()
and getBroadcastAddress(), as well as global variable broadcastAddr
are not used in consumers. Remove it.
- Make functions static
I don't know about any user of the kernel modules. It is effectively
legacy code we carry around, for no good reason. Remove it for the
moment. If we ever need it, we can revert.
Remove netlink code, and the PDCP_USE_NETLINK macro, as there is no
known use, it makes the code more complicated, and is simply "technical
debt".
In 4G PDCP, a subtle change has been introduced, in pdcp_module_init()
of pdcp.c. Looking at the diff of this commit, it can be seen that there
is now a new "else-if (ENB_NAS_USE_TUN_W_MBMS_BIT)" branch that is under
what was the "if (PDCP_USE_NETLINK)" branch, while the code fragment was
actually inside the "else" branch of PDCP_USE_NETLINK. This seems to be
necessary: previously, if we did not use noS1 mode and we don't use any
TUN (i.e., the eNB), the else block would set up this interface. It is
important that this interface is brought up, because if we omit it,
RFsim will not work. It seems to me that this interface will regularly
create some traffic; without it, RFsim will be blocked, and the UE
cannot connect.
In short, it seems to be important to have the MBMS interface, which
injects traffic in the RFsim side, which will unblock RFsim. The change
in pdcp_module_init() preserves the total changes of the if-else
(PDCP_USE_NETLINK).
Tests showed that we sometimes exceed the response window. In that case,
the UE cannot connect anymore, as do-ra uses contention-free RA, and
prefills a RA process. Avoid this by giving more time in the CI test.
Remove function pointers that were used in the past to implement the
F1(-U) interface in 4G, i.e., to have different functions to handle
split/monolithic operations. As we don't have F1 in 4G anymore (see
commit 9dc2282249), we don't need the
function pointers anymore.
On that occasion, rename the 5G functions by prepending nr_ to them;
this allows to refactor the interface in 5G further (which is not the
focus of this changeset).
Robert Schmidt