[asterisk-dev] adding SIP headers for ALL request within a dialog

[Marco Happenhofer]

Hi

I need some special SIP headers in each request within a SIP dialog. So 
I modified the chan_sip.c. I extracted the piece of code in the 
transmit_invite() function, which adds the SIP header, to a new function 
and called that function in every transmit Request function.

To verify the functionality I configured the * in B2BUA mode. Almost 
every request (coming from the initiator of the call) gets the 
preconfigured SIP headers.

But no all request will get these headers. When the * receives a BYE 
from the initiator of the call, he sends an INVITE to the other peer to 
modify the destination address for the media traffic, to its own 
address. After that INVITE transaction a BYE transaction follows. And in 
the requests after the INVITE, the ACK (which belongs to the INVITE) and 
the BYE, there are no SIP headers added. After some debugging I found 
that the p->owner points to nowhere, and the function can not be 
performed without this structure.

So my question: Is it possible to modify the code so that ALL request 
within a dialog will get the preconfigured headers?

greets