Re: [SR-Users] remove_hf() leaves junk in the headers?

On Sun, May 26, 2019 at 09:27:01PM +0300, Oded Arbel wrote: Sorry, that wasn't a very clear response on my part. I was referring to these parameters: https://kamailio.org/docs/modules/5.2.x/modules/uac.html#uac.p.restore_mode https://kamailio.org/docs/modules/5.2.x/modules/uac.html#uac.p.restore_dlg The way the uac_replace_{to,from}() mechanism works is that given an INVITE going from A to B, and passing through proxy P, P will modify the header in flight and store the original value in some fashion. Taking advantage of its role in series to the path of any replies or new in-dialog requests going from B back to A, P will statefully revert the header value to the stored original, so that A is none the wiser as to the fact that the header has been modified. Meanwhile, B will continue to see the modified value at all times. This removes the problem of the proxy P modifying these values en route in a way that gives rise to an rejection from A -- "Hey, I didn't send that!" The settings in this area mostly relate to the way in which this original value is stored. There are two ways. One is to throw it into a Record-Route header parameter, taking advantage of the proxy's role (if record_route() is called/an RR header is added upon processing the initial INVITE) in the entire life cycle of the dialog. The proxy will intercept the original value in the RR header (encoded or encrypted somehow) and revert it in messages going back to "A". The other way is to use the dialog module's runtime memory of dialogs, if enabled. This method is perhaps a bit more sanitary, but has the disadvantage of not being particularly stateless or restart-persistent. -- Alex