Class: EnigmaEngine::Crack

Inherits:
Engine
  • Object
show all
Defined in:
lib/enigma_engine/crack.rb

Instance Attribute Summary

Attributes inherited from Engine

#date, #key

Instance Method Summary collapse

Methods inherited from Engine

#characters, #decrypt, #decrypt_char, #encrypt, #encrypt_char, #handle_rotation, #rand_key

Methods included from DateKeyHelpers

#blue, #colorize, #date_valid?, #fields_empty?, #files_valid?, #green, #key_valid?, #red, #today, #yellow

Methods included from FileHelpers

#create_write_file, #open_file, #show_msg, #text_to_array

Methods included from Offsets

#a_offset, #b_offset, #c_offset, #d_offset, #get_date

Methods included from Rotors

#a_rotation, #b_rotation, #c_rotation, #d_rotation, #key, #put_key

Instance Method Details

#crack(encrypted_file, new_file, date) ⇒ Object 



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# File 'lib/enigma_engine/crack.rb', line 49

def crack(encrypted_file, new_file, date)
  res = find_key(encrypted_file)
  key = res.values.map(&:to_s).join('')
  encrypted_file = text_to_array(open_file(encrypted_file))
  cracked_chars = []
  encrypted_file.each do |row|
    row.each_with_index do |item, index|
      brk = handle_crack_rotation(index, item, res, method(:decrypt_char))
      cracked_chars.push(brk)
    end
  end
  create_write_file(cracked_chars.join(''), new_file, key, date)
end

#find_key(encrypted_file) ⇒ Object 



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# File 'lib/enigma_engine/crack.rb', line 21

def find_key(encrypted_file)
  encrypted_file = text_to_array(open_file(encrypted_file))
  char_map_with_index = Hash[characters.zip (0...characters.size)]
  target_char = get_target(encrypted_file)
  rotation = {}
  target_char[:target].each_with_index do |item, index|
    weakness_pos = char_map_with_index[target_char[:weakness][index]]
    pos = char_map_with_index[item] - weakness_pos
    (pos < 0) ? pos += 39 : pos
    case index
    when 0 then rotation[:a_rotation] = pos
    when 1 then rotation[:b_rotation] = pos
    when 2 then rotation[:c_rotation] = pos
    when 3 then rotation[:d_rotation] = pos
    end
  end
  rotation
end

#get_target(encrypted_file) ⇒ Object 



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# File 'lib/enigma_engine/crack.rb', line 15

def get_target(encrypted_file)
  res = {}
  res[:target] = encrypted_file[encrypted_file.length - 2]
  handle_get_target(encrypted_file, res)
end

#handle_crack_rotation(index, item, res, func) ⇒ Object 



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# File 'lib/enigma_engine/crack.rb', line 40

def handle_crack_rotation(index, item, res, func)
  case index
  when 0 then func.call(item, res[:a_rotation])
  when 1 then func.call(item, res[:b_rotation])
  when 2 then func.call(item, res[:c_rotation])
  when 3 then func.call(item, res[:d_rotation])
  end
end

#handle_get_target(encrypted_file, res) ⇒ Object 



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# File 'lib/enigma_engine/crack.rb', line 4

def handle_get_target(encrypted_file, res)
  case encrypted_file.last.length
  when 4 then res[:target] = encrypted_file.last
              res[:weakness] = %w(n d . .)
  when 3 then res[:weakness] = %w(. . e n)
  when 2 then res[:weakness] = %w(. e n d)
  when 1 then res[:weakness] = %w(e n d .)
  end
  res
end