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mame / doublehelix

doublehelix obfuscates Ruby codes in Double-helix style
http://github.com/mame/doublehelix
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Obfuscation #3

Open PyMaster22 opened 4 years ago

PyMaster22 commented 4 years ago

This isn't an issue I have with it it's just something I found.


$code = ""
Object.instance_eval do
  def const_missing(s); $code << s.to_s; 0; end
  remove_const(:GC)  # Holy moly!
end
at_exit do
  dict = { "AT"=>"00", "CG"=>"01", "GC"=>"10", "TA"=>"11" }
  eval([$code.gsub(/../) {|s| dict[s] }].pack("b*"))
end

def doublehelix(src)
  dict = { "00"=>["A","T"], "01"=>["C","G"], "10"=>["G","C"], "11"=>["T","A"] }
  format = [[1,0], [0,2], [0,3], [0,4], [1,4], [2,4], [3,3], [4,2], [5,0]]
  format += format.reverse
  %(require "doublehelix"\n\n) + src.unpack("b*").first.gsub(/../) do |s|
    format << (offset, dist = format.shift)
    "" * offset + dict[s] * ("" * dist) + ""
  end
end```
I removed 4 characters and the output is shortened a lot.
The `Hello World` is now `ATATTAGCGCGCTAGCATGCTAGCTAATTAGCATCGCGATCGATCGATATCGATGCGCGCCGGCATTACGGCATTACGGCTATACGGCATATCGATTAGCGCGCTATACGGCCGATTAGCATTACGGCATGCCGGCGCATCGATCGATCGATGCCGCGAT`.