asterisk users - Nov 2009 - allowguest defaults to yes for SIP

In your sip.conf file allowguest defaults to yes.  This means that 
anyone that can reach the SIP ports on that system has access to make 
unauthenticated calls, by default.  The administrator actually has to go 
in and turn it off to prevent unauthenticated SIP calls (in whatever 
context [general] points at).

Does anyone else agree with me that this is a poor default?  I'd like to 
see the default setting changed.

It seems to me that this default is the reason behind the 
doc/security.txt bias against using the "default" context for toll
calls.

Thanks,

Lee.

Lee Howard wrote:
> Does anyone else agree with me that this is a poor default?  I'd like
to
> see the default setting changed.
>
>    
I've always considered it to be good practice that something that may 
leave your system vulnerable, should be disabled by default.

So yes, I would agree.

Doug

-- 

Ben Franklin quote:

"Those who would give up Essential Liberty to purchase a little Temporary
Safety, deserve neither Liberty nor Safety."

Lee Howard a ?crit :
> In your sip.conf file allowguest defaults to yes.  This means that 
> anyone that can reach the SIP ports on that system has access to make 
> unauthenticated calls, by default.  The administrator actually has to go 
> in and turn it off to prevent unauthenticated SIP calls (in whatever 
> context [general] points at).
>
> Does anyone else agree with me that this is a poor default?  I'd like
to
> see the default setting changed.
>
> It seems to me that this default is the reason behind the 
> doc/security.txt bias against using the "default" context for
toll calls.
>   
Agree. Another possibility would be to have a guestcontext defined in 
default. This context would exist but empty.

-- 
Daniel

On Thursday 12 November 2009 07:47:34 Lee Howard wrote:
> In your sip.conf file allowguest defaults to yes.  This means that
> anyone that can reach the SIP ports on that system has access to make
> unauthenticated calls, by default.  The administrator actually has to go
> in and turn it off to prevent unauthenticated SIP calls (in whatever
> context [general] points at).
Actually, they only have access to your default context.  Whether you make
available outgoing calls in your default context is your choice.  By default,
there is no capability of making outgoing calls from your default context.
> Does anyone else agree with me that this is a poor default?  I'd like
to
> see the default setting changed.
The purpose of the allowguest option is to allow persons to call into your
system from a zero-knowledge position.  This allows you to publish a general
SIP address as a point of contact.  The reason why it is set that way in the
sample configuration is to make it easy for new users to get to that magic
moment when Asterisk first responds to their call (in essence, to get the user
"hooked").
> It seems to me that this default is the reason behind the
> doc/security.txt bias against using the "default" context for
toll calls.
Correct, you should be using something like "internal" instead.

-- 
Tilghman Lesher
Digium, Inc. | Senior Software Developer
twitter: Corydon76 | IRC: Corydon76-dig (Freenode)
Check us out at: www.digium.com & www.asterisk.org