[sr-dev] Msrp module in Kamailio relays frame back to the source instead of target

Hi users of MSRP module, I just set up MSRP module with Kamailio 4.4.3 & blink client on Windows. What I am noticing is messages are coming though one-way. When other side replies, they are relayed back to itself instead of target. Msrp layer of the relayed packet is built fine, but tcp destination is set wrong. I am suspecting it is either due to wrong use of msrp_set_dst in Kamailio.cfg (attached) or a bug in msrp_relay method in the module itself. I am new to this area, please suggest how to troubleshoot this. Find below the trace of msrp messages of the issue. My analysis of the msrp trace is in purple. Some points to note: 10.11.200.24 and 10.0.0.5 are nics on same box and are marked in same color as is called "source". 10.11.52.53 is "target" machine, where the relayed message should go to. 10.0.16.51 is the relay server Question to answer: Why is Message3 below sent to source tcp ip address (10.11.200.24) instead of target tcp address (10.11.52.53). ---------------------------------------------------------------------------------------------------- Message1 is sent from source to target + relay session Message1: 2016-11-08 15:47:17.338892 [blink.exe 26372]: 10.11.200.24:62680 --> 10.0.16.51:2855 MSRP 5f0c96c84796750d SEND To-Path: msrp://10.0.16.51:2855/s.12455.7.1628740562;tcp msrp://10.11.52.53:2855/b5e6018fca0bdddfcea2;tcp From-Path: msrp://10.0.0.5:62680/7549e765f173b8ae2250;tcp Message-ID: d54ab6cddfffb429 Byte-Range: 1-375/375 Success-Report: no Failure-Report: partial Content-Type: message/cpim From: pvenkatayogi <sip:pvenkatayogi@labsip00.cyracom.com> To: <sip:pranathi@labsip00.cyracom.com> DateTime: 2016-11-08T15:47:17.336892-06:00 MIME-Version: 1.0 Content-Type: application/im-iscomposing+xml <?xml version='1.0' encoding='UTF-8'?> <isComposing xmlns="urn:ietf:params:xml:ns:im-iscomposing"><state>active</state><contenttype>text</contenttype></isComposing> -------5f0c96c84796750d$ Message2 is sent from relay server to source with 200 OK Message2: 2016-11-08 15:47:17.418908 [blink.exe 26372]: 10.11.200.24:62680 <-- 10.0.16.51:2855 MSRP 5f0c96c84796750d 200 OK To-Path: msrp://10.0.0.5:62680/7549e765f173b8ae2250;tcp From-Path: msrp://10.0.16.51:2855/s.12455.7.1628740562;tcp Message-ID: d54ab6cddfffb429 -------5f0c96c84796750d$ Message3 is wrongly sent to source, though the to-path in msrp packet is pointing to target. Message3: 2016-11-08 15:47:17.423909 [blink.exe 26372]: 10.11.200.24:62680 <-- 10.0.16.51:2855 MSRP 5f0c96c84796750d SEND To-Path: msrp://10.11.52.53:2855/b5e6018fca0bdddfcea2;tcp From-Path: msrp://10.0.16.51:2855/s.12455.7.1628740562;tcp msrp://10.0.0.5:62680/7549e765f173b8ae2250;tcp Message-ID: d54ab6cddfffb429 Byte-Range: 1-375/375 Success-Report: no Failure-Report: partial Content-Type: message/cpim From: pvenkatayogi <sip:pvenkatayogi@labsip00.cyracom.com> To: <sip:pranathi@labsip00.cyracom.com> DateTime: 2016-11-08T15:47:17.336892-06:00 MIME-Version: 1.0 Content-Type: application/im-iscomposing+xml <?xml version='1.0' encoding='UTF-8'?> <isComposing xmlns="urn:ietf:params:xml:ns:im-iscomposing"><state>active</state><contenttype>text</contenttype></isComposing> -------5f0c96c84796750d$ Message4 is source machine rightly rejecting the Message3 above saying it is not for me. Message4: 2016-11-08 15:47:17.429911 [blink.exe 26372]: 10.11.200.24:62680 --> 10.0.16.51:2855 MSRP 5f0c96c84796750d 481 Invalid To-Path To-Path: msrp://10.0.16.51:2855/s.12455.7.1628740562;tcp From-Path: msrp://10.11.52.53:2855/b5e6018fca0bdddfcea2;tcp -------5f0c96c84796750d$ ----------------------------------------------------------------------------------------------- Pranathi Venkatayogi System Developer II (520) 745-9447 x4466 www.cyracom.com<http://www.cyracom.com/> Join us: [cid:image001.gif@01D1C9C9.C4E8B6D0] <https://www.facebook.com/pages/CyraCom-LLC/134704783312720> [cid:image002.gif@01D1C9C9.C4E8B6D0] <https://twitter.com/cyracom> [cid:image003.gif@01D1C9C9.C4E8B6D0] <http://www.linkedin.com/company/cyracom> [cid:image004.gif@01D1C9C9.C4E8B6D0] <http://www.cyracom.com/blog/> [cid:image005.png@01D1C9C9.C4E8B6D0] DISCLAIMER: This e-mail and any attached content may contain confidential or privileged material delivered for the sole use of the intended recipient(s). Any review, use, distribution or disclosure by others is strictly prohibited. If you are not the intended recipient (or authorized to receive for the recipient), please contact the sender immediately by reply e-mail and delete all copies of this message. It is the recipient's responsibility to scan this e-mail and any attachments for viruses. The content of this e-mail message, including any attachments, does not comprise a contract or a portion of a contract, and so does not bind CyraCom International, Inc. or any of its agents or subsidiaries. CyraCom, LLC and Voiance Language Services, LLC are wholly owned subsidiaries of CyraCom International, Inc.