This commit adds additional checks in the PFCP receive callback to ensure
that a complete PFCP message is received before parsing. A minimum header
length check and a total message length validation are now performed. This
prevents incomplete, fragmented messages from being processed and avoids
potential parsing errors and DoS conditions.
- Replace direct usage of OGS_ADDR/OGS_PORT macros with
ogs_sockaddr_to_string_static() for consistent IPv4/IPv6 logging.
- Remove redundant stack buffer allocations for address printing.
- Update PFCP node address handling to use addr_list and related
merges, avoiding obsolete sa_list references.
- Use ogs_pfcp_extract_node_id() and related APIs to safely extract
PFCP Node ID, improving error handling and reducing stack usage.
- Added support for the N9 For Roaming interface type:
- Core interface act as V-UPF.
- Access interface act as H-UPF.
- Modified V-UPF behavior:
- V-UPF updates only the TEID and IP Address in the GTP-U header.
- The content following the Extension Header is passed through directly
between the UE and H-UPF.
This implementation ensures seamless data flow between the UE, V-UPF, and H-UPF
while maintaining integrity for Home Routed Roaming scenarios.
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);
Scenario is handover on S1AP, data forwarding is enabled, and
the Source ENB is forwarding DL PDCP packets to EPC(SGWU)
with PDCP SN included. SGWU is also forwarding these packets
to the Target ENB.
However the PDCP SN is not present in the forwarded packets
from SGWU to Target ENB.
I modified this part, and there was the same problem in 5GC, fixed it as well.
A lot of code in GTP-U has been modified,
so if you have any problems, please let us know right away.