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1

Hi All,
Trying to modify a great script created awhile ago by community member lgaetz (I cant post a link to the post since I’m a new user, sorry!) to prevent spam and robocallers.

Brand new to custom Asterisk dialplans, so I apologize in advance if the code is messy. I’m having issues trying to conceptualize how to manipulate/read one of the variables generated by a random generator to control the call flow. Here’s what I have so far:

[bender-blocker]
exten => s,1,Noop(Entering context bender-blocker in extensions_custom.conf)
exten => s,n,Answer
exten => s,n,Set(count=0)
exten => s,n(restart),Set(goal=${RAND(0,9)}) ; generates a random number, modify as req'd

exten => s,n,ExecIf($["${goal}"="1"]?SayDigits(1)) ; will assign discrete Playback() files later that I recorded
exten => s,n,ExecIf($["${goal}"="2"]?SayDigits(2))
exten => s,n,ExecIf($["${goal}"="3"]?SayDigits(3))
exten => s,n,ExecIf($["${goal}"="4"]?SayDigits(4))
exten => s,n,ExecIf($["${goal}"="5"]?SayDigits(5))
exten => s,n,ExecIf($["${goal}"="6"]?SayDigits(6))
exten => s,n,ExecIf($["${goal}"="7"]?SayDigits(7))
exten => s,n,ExecIf($["${goal}"="8"]?SayDigits(8))
exten => s,n,ExecIf($["${goal}"="9"]?SayDigits(9))
exten => s,n,ExecIf($["${goal}"="0"]?SayDigits(0))

exten => WaitExten()

exten => ${goal},n,Return ; conceptually would like to use ${goal} variable to control which is a valid extension and return it to the FPBX call flow

exten => i,1,Playback(invalid_option)
exten => i,n,Goto(restart)

exten => t,1,Playback(goodbye)
exten => t,n,Hangup()

I am using the WaitExten() application to handle timeouts and if the caller were to press digits while a recording is being played.

Thanks in advance!

2

Welcome to the community Chris, sharing links available you now.

First I will say, while doing these types of projects is fun, in my experience spam calls are pretty much all robots, so can be stopped by a simple IVR.

Comments on your dialplan:

  • WaitExten line is malformed, it will just stop execution there
exten => s,n,WaitExten()
  • The individual ExecIf lines are unnecessary unless you have future plans to interact with the caller differently depending on the value of ${goal}, they can all be replaced with:
exten => s,n,SayDigits(${goal}))
  • You can’t use a variable for a dialplan exten like you have, you will need something like this:
exten => _X,1,execif($["${EXTEN}"="${goal}"]?Return)
exten => _X,n,goto(bender-blocker,s,restart)

Once you have this working, you will want to use it in conjunction with the Allow List module so you don’t challenge known callers.

3

Figured it out! Thanks so much for the _X extension - that did the trick. For anyone interested, here is the code I currently have working:

[bender-blocker]
exten => s,1,Noop(Entering context bender-blocker in extensions_custom.conf)
exten => s,n,Answer
exten => s,n,Set(Count=0)
exten => s,n(restart),Set(goal=${RAND(0,9)}) ; generates a random number, modify as req'd
exten => s,n,GotoIf($["${Count}"="3"]?bender-blocker,123,1)   ; bail after 3rd attempt

;  will assign discrete Playback() files later that I recorded
; exten => s,n,ExecIf($["${goal}"="1"]?Background())

exten => s,n,SayDigits(${goal})
exten => s,n,WaitExten()

; valid press handler
exten => _X,1,ExecIf($["${EXTEN}"="${goal}"]?Return)

; invalid press handler
exten => i,1,Playback(badinput)
exten => i,n,Set(Count=$[${Count}+1])
exten => i,n,Goto(bender-blocker,s,restart)

; timeout handler
exten => t,1,Playback(noinput)
exten => t,n,Set(Count=$[${Count}+1])
exten => t,n,Goto(bender-blocker,s,restart)

; what do you want to do with calls that fail?
exten => 123,1,Playback(goodbye)
exten => 123,n,Hangup()

Wondering now, if its not too complicated, to have WaitExten handle multiple digits? In the original code I believe you had it generate a 4 digit PIN. Either that or if the user would have the ability to press # or * at the end of the prompt to terminate input.

4

That’s what the original dialplan does. You can modify the line that sets the goal to however many digits you want.

5

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