[OpenSER-Users] The best way to allow just a few destinations based on prefix?

[Henning Westerholt]

On Tuesday 19 February 2008, Phil D'Amore wrote:
> It looks like you may have settled on a solution already but I'd like
> to add that carrierroute will do what you are looking for as well with
> a little work, as I do exactly this already.  I have some customers
> that are only allowed to call certain prefixes (more specific than
> entire countries, but same principle).
>
> What you do is create a route tree for every unique situation you
> have, and then add the allowed routes to each tree.  For your example
> it would look something like this (requires openser 1.3):
>
> route_tree table:
> [...]
> # HEre's a cheap way to do a blackhole route using this stuff.
> # You create a carrierroute entry and instead of a gateway host in the
> rewrite_host
> # column, just us ethe string "blackhole".  Then you can do something like
> this: if($rd == "blackhole") {
>     acc_db_request("403 Blackhole route", "acc");
>     sl_send_reply("403", "Forbidden");
> }

Hi Phil,

just to give a little bit more informations, the solution you use if of course 
also valid.. If you want to blacklist some prefixes on a global level then 
you could also use something like this approaches:

1.
- use a sufficient long strip value
- add a prefix, e.g. "blacklist"
- set rewrite_host to some asterisk box

This way the the resulting URI will transformed like this:

4912 at proxy.domain -> blacklist at asterisk.domain

The call will be routed to a asterisk box, where you could play some user 
information matching to the prefix. 

2. 
- use a empty rewrite_host string

This way the resulting URI will be invalid, and not routed.

Cheers,

Henning