ISUP Mangler

Latest revision as of 15:06, 26 October 2017

This is a special module that allows intercepting and mangling ISUP messages that pass through the STP.

Several different manglers can be defined in the configuration file.

On matching an Initial Address Message (IAM) an isup.Mangle message is dispatched allowing its parameters to be changed before the message is forwarded.

Note: This feature module is not loaded automatically, it needs a line in yate.conf:
[postload]
${modulepath}/sig/isupmangler${modsuffix}=yes

[edit] Configuration file

; IMPORTANT!
; This feature module is not loaded automatically, it needs a line in yate.conf:
; [postload]
; ${modulepath}/sig/isupmangler${modsuffix}=yes


; Each section in this file describe an ISUP interceptor/mangler
; You can add, remove or disable sections and reload to apply the changes


;[mangler_name]
; The name of the mangler is reported in the address parameter with the CIC

; enable: boolean: Enable the mangler (default)
;enable=yes

; service: int: Service Information Field (protocol number)
; It is unlikely you will ever need to modify it
;service=5

; netindicator: keyword: Value of Network Indicator bits in the SIO
; Allowed values: international, spareinternational, national, reservednational
;netindicator=national

; pointcodetype: string: SS7 point code type (required)
; Can be one of ITU,ANSI,ANSI8,China,Japan,Japan5
;pointcodetype=

; defaultpointcode: string: DPC of the ISUP messages to match
;defaultpointcode=

; remotepointcode: string: OPC of the ISUP messages to match
;remotepointcode=

; symmetric: boolean: Match and mangle messages in the opposite direction too (DPC->OPC)
; Symmetric should be enabled if intercepting more than just IAM
;symmetric=no

; cic_min: int: Minimum circuit code to match
;cic_min=1

; cic_max: int: Maximum circuit code to match
;cic_max=16383

[edit] Notes

• It is currently not possible to intervene in the message flow of a call (insert or remove messages) because that can desynchronize the communicating parties.
• The OPC, DPC, SLS and CIC of the message cannot be changed as that will break basic SS7 and ISUP assumptions. You can however alter them by configuration which applies to all ISUP messages.
• You must not alter the continuity check flags as it would cause the test to fail or the loopback to be left in place indefinitely.

See also

• Modules
• isup.Mangle Message