If eg. PCRF or AAA diameter link is not yet ready (eg. PCRF crashed), and
a client sends a CreateSessionRequest announcing its ow F-TEID,
then open5gs-smfd answers with Create Session Response Cause=
"Remote peer not responding", but it is not setting the received F-TEID
in the header of the response, instead it sends with TEI=0.
As a result, the peer cannot match the CreateSessionResponse, and needs
to rely on its own timeout timer to figure out that specific request failed.
This also happens in PFCP, so to solve this problem, I added teid/seid_presence
to the interface that sends the error message as shown below.
void ogs_gtp2_send_error_message(ogs_gtp_xact_t *xact,
int teid_presence, uint32_t teid, uint8_t type, uint8_t cause_value);
void ogs_pfcp_send_error_message(
ogs_pfcp_xact_t *xact, int seid_presence, uint64_t seid, uint8_t type,
uint8_t cause_value, uint16_t offending_ie_value);
For bi-directions, the rules are created in the same form as for downlink
as shown below, so to apply them for uplink, we need to swap the rules
according to the interface.
RX : permit out from <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT> to <UE_IP> <UE_PORT>
GX : permit out from <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT> to <UE_IP> <UE_PORT>
PFCP : permit out from <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT> to <UE_IP> <UE_PORT>
RULE : Source <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT> Destination <UE_IP> <UE_PORT>
TFT : Local <UE_IP> <UE_PORT> REMOTE <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT>
RX : permit in from <UE_IP> <UE_PORT> to <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT>
GX : permit out from <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT> to <UE_IP> <UE_PORT>
PFCP : permit out from <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT> to <UE_IP> <UE_PORT>
RULE : Source <UE_IP> <UE_PORT> Destination <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT>
TFT : Local <UE_IP> <UE_PORT> REMOTE <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT>
As mentioned in the sgwu.yaml configuration file, it is possible to configure multiple addresses with different source_interface values for the gtpu interface.
Following the this section, I defined two addresses, one with source_interface set to 0 and another with source_interface set to 1. My expectation was to see different addresses for the two PDRs in the Session Establishment Response message during session establishment. However, both addresses were the same, and it was the address I had set for source_interface = 0.
When I looked into the code, I found the reason for the issue. In the lib/pfcp/context.c file, on line 1185, the function that determines the address is called as follows:
...
} else {
ogs_gtpu_resource_t *resource = NULL;
resource = ogs_pfcp_find_gtpu_resource(
&ogs_gtp_self()->gtpu_resource_list,
pdr->dnn, OGS_PFCP_INTERFACE_ACCESS);
if (resource) {
...
In the last parameter of this function, a constant value, OGS_PFCP_INTERFACE_ACCESS, is used. This causes every PDR with any source_interface to be considered as "access," and the value 0 is used for its interface.
I replaced the value with pdr->src_if, and the bug was resolved.
A problem occurred when there was one SGWU/UPF and multiple SGWC/SMF.
When SGWU and UPF create a session, if the SEID is the same,
the existing session information is used without creating an additional session.
These problems were solved by using the F-SEID including IP information
in the process of checking the existing session.
For video in VoNR, multiple QosFlow is required in one session.
In the past, since only one Session Modification Message was supported,
QoS-Flow was put into several Session Messages one by one and processed.
Now that multiple QoS-Flows can be supported,
it is optimized to process one session modification message.
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.
* Fix conversion from IPFilterRule to packet filter
As per 3GPP TS 24.008, following Packet filter component type identifier
are not supported on the LTE pre release-11 UEs:
IPv4 local address type
IPv6 remote address/prefix length type
IPv6 local address/prefix length type
And,
IPv6 remote address/prefix length type and
IPv6 local address/prefix length type shall be used when both MS and
Network support Local Address in TFTs.
This commit add logic to omit adding local address in packet filters
for compatibility with pre-release LTE 11 devices. The following parameter
could be used to toggle omit/no to omit behavior.
parameter:
no_ipv4v6_local_addr_in_packet_filter: <true/false>
* Remove logic of supporting pre-release LTE 11 devices in PCRF
commit 183d8b8344122f25f77be79b1b698c71f48c1656
Author: Sukchan Lee <acetcom@gmail.com>
Date: Fri May 28 23:44:26 2021 +0900
[SMF] introduce new list API [#1019]
Sometimes we may need two lists for same node.
To do this, I created a new list API, and applied it this pull request.
This commit address the issue where a bearer with particular
PCC rule name exists with TFTs and addtional TFTs needs to be added
to same bearer and DRB lost is reported by UE.
This is achieved by creating EPS Bearer Level Traffic Flow Template
with TFT operation code as 'OGS_GTP_TFT_CODE_ADD_PACKET_FILTERS_TO_EXISTING_TFT' in
above scenario rather than use 'OGS_GTP_TFT_CODE_CREATE_NEW_TFT' at all times.
And, not remove existing packet filters for the bearer.
All process will be forcely exited if it failed to encode the S1AP/NGAP/GTP/PFCP message. It is to make sure there was no problem with the encoding of open5gs.
* Preserve local port in Rx flow-description
In contnuation to support for calling in pre-rel. LTE 11 devices
, rather than removing the local IP addr field and local port remove
only the IP addr field
* tft: Set precedence considering exisiting TFTs in all bearers of a DNN
Sukchan Lee
Pau Espin
Supreeth Herle