[asterisk-dev] SipAddHeader and SIP REFER

[Stefan Schmidt]

Am 14.03.2011 21:35, schrieb Kirill Katsnelson:
> Additional headers from SIPAddHeader are not added to the REFER packet.
> This is a practical case for us now.
> 
> The machinery is all there, so it seems an easy fix. I do not know,
> however, what is the best way to implement the functionality so it might
> be useful to everyone. I see the following options:
> 
> 1. Just always add the headers if set in the dialplan, just like it is
> done with the INVITE.
> 
> 2. Create an option in sip.conf that would enable behavior (1), default
> off.
> 
> 3. Extend Transfer() application with a flag argument, and a flag to
> enable sending the extra headers.
> 
> 4. Do not release a patch. Nobody would be interested anyway.
> 
> I would be all for the option (1); however, it might have regression
> implication, if someone's implementation depends on not sending the
> extra headers. Cannot think of an RFC compliant SIP implementation that
> would be really broken, but can cause e. g. unintended information leak.
> 
> (2) seems a good compromise in this case, while (3)seems overcomplicated
> to me.
> 
> What do you think?
> 
>  -kkm

Hello,

1. i dont know if this really would be a good idea. Just think about the
Sip message size which will allways be a problem if you add too much
headers.

2. would be ok IMHO but i would like to see more specified parameters,
like enable for refer, enable for bye ....

3. and 4. sounds not really interesting for me ;)

btw take a look how the x-hangupcause is added to the bye header. This
could be a good way to implement this if you can ensure to not slow down
the sending itself ;)


best regards

stefan