How to work with BlackList? - asterisk

Question

I am new to asterisk. i am working under ubuntu 9.10. I use asterisk 1.8. I want to create a conference room.
in meetme.conf
conf => 1234,1234
in extensions.conf
exten =>1234,1,MeetMe(1234)
Is the pin number a secure one? How to create a secure pin number (do i have to use numbers and characters too)? Secondly how to create a blacklist? If a person tries to register 3 times..and the passed is incorrect how can I put him/her on the blacklist?

Answer 1

Passwords are numbers, however, '1234' is not a good password choice.
Asterisk's dialplan is extremely dynamic; there is no single definition of 'Blacklist'. However, try something like this:
== meetme.conf
conf => 1234
== extensions.conf
exten => 1234,1,GotoIf(${BLACKLIST()}?hangup)
exten => 1234,n(loop),Set(TRIES=$[0${TRIES} + 1]);
exten => 1234,n,GotoIf($["$TRIES" = "3"]?blacklist)
exten => 1234,n,Read(PIN,enter-conf-pin-number,4)
exten => 1234,n,GotoIf($["$PIN" = "9999"]?meetme)
exten => 1234,n,Goto(loop)
exten => 1234,n(meetme),MeetMe(1234)
exten => 1234,n,Hangup
exten => 1234,n(blacklist),Set(CALLERID(num)=${FILTER(0-9\-,${CALLERID(num):-10})})
exten => 1234,n,Set(DB(blacklist/${CALLERID(num)})="Some Comment")
exten => 1234,n(hangup),Hangup
there are all sorts of other ways. this particular setup will only keep the caller from trying to authenticate into that one conference room. if you'd rather ban him from ever touching your automated attendant, you can move the first line to your incoming context.
If you're already sanitizing your callerid (you should be) you can remove the FILTER line and bump the (blacklist) to the next line.