[SR-Users] Sending in-dialog requests from custom module's C code

I’m working on a custom Kamailio module where I need to send new-dialog and in-dialog requests on timer (hence I’m being forced to generate new messages from C code). So far I’ve been using modules/tm/tm_load.h defined interface to generate messages and handle callbacks. New dialog messages are sent and processed normally. To do that I’m: 1. Calling set_uac_request() to define request parameters 2. Calling tmb.t_request_outside() to send it outside any existing dialog I was able to send in-dialog requests (or so I thought) in a similar fashion, but I soon realised that responses to those requests were dropped because they couldn’t be matched against any known existing transaction. I’m attaching log messages that I believe support this theory and I’ve also observed UDP retransmissions. tm [t_lookup.c:897]: t_reply_matching(): t_reply_matching: hash 50576 label 0 branch 0 tm [t_lookup.c:990]: t_reply_matching(): no matching transaction exists tm [t_lookup.c:993]: t_reply_matching(): failure to match a transaction tm [t_lookup.c:1088]: t_check_msg(): msg (0x5abcb50) id=1 global id=1 T end=(nil) tm [t_reply.c:2195]: reply_received(): transaction not found - (branch -1) The way I’m currently generating in-dialog requests is very similar to what tmb.t_request_outside() does, the main difference being that I do the dialog setup manually, based on the call-ID, cseq and from/to tags (I’m tracking transaction identifiers separately) and then pass resulting uac_req_t to tmb.t_request_within() - https://gist.github.com/IvanRibakov/3302cb286b1f4b786d109b406f2435a2 <https://gist.github.com/IvanRibakov/3302cb286b1f4b786d109b406f2435a2> Now, the question part - does anyone know what I’m doing wrong/missing? As I mentioned, when looking at the generated message bodies, they look ok to me (left - initial request that started the dialog, right - first in-dialog request), so I’m guessing I’m missing some Kamailio internal steps needed to register new transaction. SIP flow (up to the point when first UDP retransmission happens) I apologise in advance for the bulky question and will be extremely thankful for any guidance. Regards, Ivan