How can I get SIP/SDP values to a variable?

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Asterisk Users 2 Comments

Hello all!

I wonder if there’s a way to read SDP values into a variable in Asterisk? I have successfully used SIP_HEADER function to get all I want out of SIP part of the message, no problem. But I would like to be able to read SDP part as well, anyone?
Reason I want to to this is: testing the SIP_ALG condition in incoming invite message. Majority of cases can be detected just by comparing src ip address and “via”, but some devices only rewrite SDP “c” value for example and so on …
I haven’t found any information anywhere how to achieve reading SDP with asterisk. I can use 1.8 and 10 versions.

Thanks in advance

Rennes Neps
Elion Ettevõtted AS
rennes.neps@elion.ee

 

2 thoughts on - How can I get SIP/SDP values to a variable?

  • There is no mechanism in Asterisk to do this. The most practical
    approach would probably be to put a stateless SIP proxy in front of
    Asterisk and write whatever logic you like there, causing it to add one
    or more headers to the SIP messages that can be accessed from the
    dialplan in Asterisk.