Master the FRA challenge

If you seek work at FRA (the military unit handling signal intelligence, now also in cables) you need to pass a test. The challenge is in Swedish and you have to be a Swedish citizen in order to get the job, but anyway you need to deciper a piece of code (x86 assembler) which will give you a string. It’s a quite nice lite stack excersise and even if you didn’t understand that, I guess you can tell the core part of the code anyway.

http://fra.easycruit.com/vacancy/547834/58086?iso=se

Just to shhow off, please find my piece of Delphi code below. Create a form, throw in a button and an editbox. Add the code to the event handler of the button:

procedure TForm1.Button1Click(Sender: TObject);
const
indata : Array[1..20] of Byte = ($76,$75,$74,$2a,$63,$74,$66,$26,$7a,$6f,$24,$6f,$65,$6f,$63,$7c,$74,$7c,$74,$71);

var
outdata : string;
counter : byte;
begin

for counter := 1 to 20 do begin
outdata := outdata +  Chr(indata[counter] XOR Counter)
end;

Edit1.text := outdata;

end;

Sorry – the editor f*cked up my indentation 😉

Well it starts there. With the URL you are supposed to go on  with phase 2 😉