Fr-Soltanzadeh created an issue (kamailio/kamailio#4164)
### Description In a IMS lab using Kamailio PCSCF, ICSCF and SCSCF default configs, I have used TOPOH module in PCSCF for topology hiding. Topoh config is as follows: ``` modparam("topoh", "mask_key", "my-key") modparam("topoh", "mask_ip", "127.0.0.2") modparam("topoh", "sanity_checks", 1) ``` As shown in attached traffic, SCSCF IP is not hided in 180 ringing and 200ok messages to the caller. In invite, ack and bye messages hiding is performed well.
[topoh.zip](https://github.com/user-attachments/files/19086420/topoh.zip)
[topoh.zip](https://github.com/user-attachments/files/19086428/topoh.zip)
[topoh.zip](https://github.com/user-attachments/files/19086431/topoh.zip)
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### Troubleshooting
#### Reproduction
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#### Debugging Data
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``` (paste your debugging data here) ```
#### Log Messages
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#### SIP Traffic
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``` (paste your sip traffic here) ```
### Possible Solutions
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### Additional Information
* **Kamailio Version** - output of `kamailio -v`
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* **Operating System**:
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``` (paste your output here) ```