[asterisk-users] Extensions of sip trunk

[Daniel Tryba]

On Mon, Jun 05, 2017 at 06:10:50PM +0200, Hans-Peter Jansen wrote:
> ; matches 12345678099, too
> exten => _1234567800,1,Dial(SIP/int)
> 
> Except from SIP invite with tcpdump:
> 
> INVITE sip:123456780000 at provider:5060 SIP/2.0
> From: <sip:013579246800 at provider>;tag=as6bc7cbbc
> To: <sip:1234567800099 at other:5060>

12345678099 doesn't match _1234567800. The problem is the other side is
setting the R-URI to sip:123456780000 at provider for any number, so the
EXTEN matched in the dialplan is 123456780000. Ask them to fix this
problem.

> I wonder, if I really need to grab the extension with 
> Set(DN=${SIP_HEADER(TO):5}) or something similar?

Yes, something like if they can't fix the R-URI:
exten => X_.,n,Set(TO=${CUT(SIP_HEADER(To),@,1)})
exten => X_.,n,Set(TO=${CUT(TO,:,2)})
exten => X_.,n,Goto(somewhereelsetopreventloops${TO},1)

> Another issue is, that I don't like asterisk to decline foreign INVITE 
> requests. Any best practices from within asterisk on how to ignore SIP 
> invitations, that don't match certain criteria (neither local nor from sip 
> provider)?

Don't enable guest access, or send any unknown/guest to a context that
will just hangup.