[sr-dev] [kamailio/kamailio] Retaining Contact Header for 301, 302 requests when using Topoh module (Issue #3256)

### Description After I turned on topoh module, the forwarding call flow seems to break. This might be caused by the Contact header on Redirecting request is masked. ### Expected behavior The Contact header in 301, 302 SIP message will not be masked, and the forward call will succeed. #### Actual observed behavior The 302 SIP Contact header gets masked by 127.0.0.1 (masked_ip). #### SIP Traffic ``` 2022/10/05 13:47:58.093790 192.168.1.109:5060 -> 192.168.1.66:55709 SIP/2.0 302 Moved Temporarily Via: SIP/2.0/TCP 192.168.1.66:58554;received=192.168.1.66;branch=z9hG4bK-524287-1---493db1f2d8f51001;rport=55709 Record-Route: <sip:127.0.0.1;line=sr-N6IAzBFsMJZfWBc7MmZfMxq-W.y6Mx1LMBu5oB1dNB1EpSthH.3sW6WBW.Vlz6aYgxuqMB37z.pBMP**> Record-Route: <sip:192.168.1.109;transport=tcp;r2=on;lr;ftag=697cc523;did=d26.97c1> From: <sip:1000@192.168.1.109;transport=TCP>;tag=697cc523 To: <sip:1001@192.168.1.109>;tag=1357659545 Call-ID: g_hnmT8yukR7M9QxI-t6jA.. CSeq: 2 INVITE Contact: <sip:127.0.0.1;line=sr-N6IAzBj6M.KyM.qLOBF6zGZfOBF6W.vuMxNA> Supported: replaces, path, timer User-Agent: Grandstream GXP1620 1.0.4.106 Diversion: <sip:1001@192.168.1.165:5070>;reason=unconditional Allow: INVITE, ACK, OPTIONS, CANCEL, BYE, SUBSCRIBE, NOTIFY, INFO, REFER, UPDATE, MESSAGE Content-Length: 0 ``` ### Possible Solutions The behavior becomes normal when I turn off the topoh module. Hence, I think this can be solved by retaining the Contact header for 301, 302 requests when using topoh. ### Additional Information * **Kamailio Version** - output of `kamailio -v` ``` kamailio 5.4.5 ``` * **Operating System**: ``` Centos 7 ``` [topoh_302.tar.gz](https://github.com/kamailio/kamailio/files/9714508/topoh_… -- Reply to this email directly or view it on GitHub: https://github.com/kamailio/kamailio/issues/3256 You are receiving this because you are subscribed to this thread. Message ID: &lt;kamailio/kamailio/issues/3256(a)github.com&gt;