AN-Trusted AVP is only relevant for non-3GPP access networks e.g. WLAN.
This commit adds a check for non-3GPP access network in order to include
AN-Trusted AVP in CCR or not.
Also, clears the M bit for AN-trusted AVP as per TS 29.212 version 16.4.0, Table 5.4.0.1
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.
Catch Origin-Host during CCA and set it as Destination-Host during
subsequent CCRs. This way we ensure UPDATE/TERMINATION Requests are sent
back explicitly to the same Diameter peer. Moreover, it seems
freediameter relies on this AVP to properly send the message over the
correct SCTP association when several diameter peers are available.
As per 3GPP TS 23.401 version 15.12.0, section 5.3.1.2.2
The PDN GW allocates a globally unique /64
IPv6 prefix via Router Advertisement to a given UE.
After the UE has received the Router Advertisement message, it
constructs a full IPv6 address via IPv6 Stateless Address
autoconfiguration in accordance with RFC 4862 using the interface
identifier assigned by PDN GW.
For stateless address autoconfiguration however, the UE can
choose any interface identifier to generate IPv6 addresses, other
than link-local, without involving the network.
And, from section 5.3.1.1, Both EPS network elements and UE shall
support the following mechanisms:
/64 IPv6 prefix allocation via IPv6 Stateless Address
autoconfiguration according to RFC 4862, if IPv6 is
supported.
* [CORE] tlv: Store mode in ogs_tlv_t
This allows specifying the format of the IE for each individual IE,
hence allowing messages containing IEs formatted in different ways.
This is needed in order to support parsing GTPv1-C, since messages
contain IEs with different structure (TLV vs TV). Hence, this is a
preparation patch to add support for parsing TVs in ogs-tlv.c/.h.
* [CORE] tlv: Support parsing msg with both TLV and TV in it
IEs of type TV are sometimes used in GTPv1-C. Current tlv parser/builder
doesn't provide with ways to parse messages which contain TV formatted
IEs. This patch adds the relevant types and ways to encode/decode them.
Furthermore, the current parser/builder allows parsing/building messages
containing the exact same format in all its IEs. A new parser function
is added which allows parsing messages of different types (TV, TLV)
mixed in the same message. In order to be able to do so, it uses the
general msg_mode passed to it in order to know the general TLV format
(in essence, the length of the Tag field, and also the length of the
Length field if applicable each IE).
Looking up the instance in the TLV description is left undone and
hadcoded to 0, since the only user so far requiring this API is GTPv1-C,
which has no instances.
* [CORE] tlv: Support repeated tag+instance parsing TLV message
In GTPv2C, repeated IEs (same tag) are easily differentiated by the
Instance byte, which provides info to match different decoded
structures. In GTPv1C though, there's no Instance byte, and we still
encounter repeated IEs (like GSN Address in Create PDP Context Request).
Hence, the TLV decoder needs to be updated to track count of IEs found
(identified by tag+instance, where instance is always 0 in GTPv1C) and
get the proper description index + offset into the decoded structure.
* [GTP]: Move GTPv2-C specifics to its own libgtp subdir
This will allow adding GTPv1-C code by the side. Most GTPv2 code is left
in this patch as "gtp" instead of renaming it to "gtp2" in order to
avoid massive changes. It can be done at a later stage if wanted.
* [GTP] Support generating GTPv1-C messages
* [SMF] Add Gn interface support
This patch introduces GTPv1C support to open5gs-smfd. With it,
open5gs-becomes a GGSN too, where SGSN can connect to, hence supporting
GERAN and UTRAN networks.
Sukchan Lee
Supreeth Herle
Pau Espin