Bug ID 1213469: MRF SIP ALG: INVITE request with FQDN Route header will not translate SDP and 200 OK SDP is dropped

Last Modified: Oct 09, 2024

Affected Product(s):
BIG-IP LTM(all modules)

Known Affected Versions:
16.0.0, 16.0.0.1, 16.0.1, 16.0.1.1, 16.0.1.2, 16.1.0, 16.1.1, 16.1.2, 16.1.2.1, 16.1.2.2, 16.1.3, 16.1.3.1, 16.1.3.2, 16.1.3.3, 16.1.3.4, 16.1.3.5, 17.0.0, 17.0.0.1, 17.0.0.2, 17.1.0, 17.1.0.1, 17.1.0.2, 17.1.0.3

Fixed In:
17.1.1, 16.1.4

Opened: Dec 28, 2022

Severity: 4-Minor

Symptoms

BIG-IP does not translate the SDP or via headers IP with listener IP for an outbound call which causes it to drop the 200 OK response.

Impact

Media pinholes are not created for INVITE.

Conditions

In SIP ALG, the INVITE request contains an FQDN Route header.

Workaround

In the SIP_REQUEST event, a specific Route header could be removed and Insert it again in the SIP_REQUEST_SEND event before sending the request out. For example, when SIP_REQUEST { set pd_route_hdr_count [SIP::header count Route] set pd_route_unset 0 set pd_route [SIP::header Route] if {[SIP::method] == "INVITE" && ($pd_route_hdr_count equals 1) && $pd_route contains "sip:someclient.site.net;lr" } then { SIP::header remove "Route" set pd_route_unset 1 } } when SIP_REQUEST_SEND { if {[SIP::method] == "INVITE" && ($pd_route_unset == 1)} { SIP::header insert "Route" $pd_route } }

Fix Information

In SIP ALG, if the Route header is FQDN in INVITE, then it should allow it to pass without any modification.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips