Recent commit re-enabling SBI HTTP/1.1 support
(10bdf39505cf525b95886c140b3c2e82e7427d29) started using libmicrohttpd's
API MHD_create_response_from_buffer_with_free_callback(), which is only
available starting from v0.9.61.
As a result, compilation in xUbuntu 18.04 started failing with errors
about the function not being found, since it ships with libmicrohttpd
v0.9.59.
Depending on 0.9.61 is fine since it's quite old (november 2018) and all
major current distros should for sure have an >= one. Let's simply bump
the version check so that it fails in an informative manner.
For null protection scheme the SUCI needs to be BCD encoded. Whereas for
protection scheme profiles A and B the SUCI needs to be converted from
hexadecimal to ASCII.
This still needs the support for protection schemes A and B in UDM to
work.
* Initial metrics support based on Prometheus
This commit introduces initial support for metrics in open5gs.
The metrics code is added as libogsmetrics (lib/metrics/), with a well
defined opaque API to manage different types of metrics, allowing for
different implementations for different technologies to scrap the
metrics (placed as lib/metrics/<impl>/. The implementation is right now
selected at build time, in order to be able to opt-out the related dependencies
for users not interested in the features. 2 implementations are already
provided in this commit to start with:
* void: Default implementation. Empty stubs, acts as a NOOP.
* prometheus: open5gs processes become Prometheus servers, offering
states through an http server to the Prometheus scrappers. Relies on
libprom (prometheus-client-ci [1] project) to track the metrics and format
them during export, and libmicrohttpd to make the export possible through
HTTP.
[1] https://github.com/digitalocean/prometheus-client-c
The prometheus-client-c is not well maintained nowadays in upstream, and
furthermore it uses a quite peculiar mixture of build systems (autolib
on the main dir, cmake for libprom in a subdir). This makes it difficult
to have it widely available in distros, and difficult to find it if it
is installed in the system. Hence, the best is to include it as a
meson subproject like we already do for freeDiameter. An open5gs fork is
requried in order to have an extra patch adding a top-level
CMakeList.txt in order to be able to includ eit from open5gs's meson
build. Furthermore, this allows adding bugfixes to the subproject if any
are found in the future.
* [SMF] Initial metrics support
* [SMF] Add metrics at gtp_node level
* docs: Add tutorial documenting metrics with Prometheus
According to the following standards the response to the endpoint
/nudm-sdm/${supi}/sm-data should be an array of
SessionManagementSubscriptionData objects, instead of only one object.
TS 29.503 version 16.6.0
TS 29.505 version 16.4.0
UDR now responds to the request with only item in the array.
UDM copies all items as is.
SMF uses only the first item in the array, even if there are more
present.
* [SMF] rename function s/gtp/gtp2/
* [SMF] Store GTPC version in session
So far we always depended on an xact being present in the code path in
order to know which kind of session it is (GTPv1C vs GTPv2C). Let's
instead store that information in smf_sess_t so that we have it always
available in an easy way.
* [SMF] Move smf_sess_t GTPv1C specifics into gtp substruct
* [SMF] Gy CCR: append 3GPP-NSAPI AVP
* [SMF] Append PDP-Address AVP to Gy CCR msg
* [SMF] Gy CCR: Move some AVPs under Service-Information/PS-Information
They belong there. Nokia infocenter documentation seems to be document
the possibility to configure its software to have it in top level, but
that's not what 3GPP TS 32.299 states, so let's stick to it.
* [SMF] Gy CCR: append 3GPP-PDP-Type AVP
* [SMF] Gy CCR: append 3GPP-Charging-Id AVP
* [SMF] Gy CCR: append SGSN-Address AVP
* [SMF] Gy CCR: append GGSN-Address AVP
In the past only GTPv2C was supported, and had the "gtp" generic prefix.
Later on, GTPv1C support was added, and "gtp1" prefix was used.
Let's move GTPv2C specific bits to have "gtp2" prefix too, and leave
"gtp" prefix for generic stuff among different GTP versions.
The use of the Gy interface (SMF acting as CTF towards an OCS node) is
mandated through configuration file. Default value "enable: auto" will
only make use of it in case a Diameter peer announcing support for the
Credit-Control Application is found.
Upon subscriber session creation, and after auth check over Gx, the SMF
will create a Gy session with the OCS and only after that step the SMF
will accept the session back to the subscriber.
The OCS may then grant some traffic volumes/time and ask to be notified
back with updated measurements.
In order to get the measurements, the SMF relies on PFCP URR configured
to the UPF through Session Repoort Request messages.
When closing the subscriber session, the SMF will also terminate the Gy
session at the OCS.
So far only some specifics parts of the Gy interface as well as the PFCP
side are implemented. Those should be enough to at least have
volume/time thresholds granted by the OCS, which then will be able to
track subsriber resource use.
This patch doesn't implement the OCS side of the Gy interface, that's
left as a future exercise. The interface was tested using an OCS
emulator implemented in TTCN-3 [1]
[1] https://cgit.osmocom.org/osmo-ttcn3-hacks/
Alexander Couzens
root
Sukchan Lee
Pau Espin
Bostjan Meglic
mitmitmitm