My Hash function

[Joke758]

I made an hash function similar to MD5.

Here's my script:

expandcollapse popup

While 1
    $exemple = Inputbox ( "Hash", "Type a message", "", "", -1, 100, -1, -1 )
    Msgbox ( 0, "Hash", hash($exemple ))
WEnd

Func hash($string)
    Dim $k[64]
    Dim $r[64] = [7, 12, 17, 22,  7, 12, 17, 22,  7, 12, 17, 22,  7, 12, 17, 22, 5, 9, 14, 20,  5,  9, 14, 20,  5,  9, 14, 20,  5,  9, 14, 20, 4, 11, 16, 23,  4, 11, 16, 23,  4, 11, 16, 23, 4, 11, 16, 23, 6, 10, 15, 21, 6, 10, 15, 21,  6, 10, 15, 21,  6, 10, 15, 21]
    Local $h0 = 0x67452301
    Local $h1 = 0xEFCDAB89
    Local $h2 = 0x98BADCFE
    Local $h3 = 0x10325476
    Local $w = __MessageInit ( $string )
    
    $a = $h0
    $b = $h1
    $c = $h2
    $d = $h3
    
    For $i = 0 to 63
        $k[$i] = Floor(Abs(Sin($i + 1)) * 2^32)
    Next
    For $loop = 1 to 16
        For $i = 0 to 63
            If 0 < $i < 15 Then
                $f = BitOr(BitAND ( $b, $c ), BitAnd(BitNOT ( $b ), $d))
                $g = $i
            ElseIf 16 < $i < 31 Then
                $f = BitOr ( BitAnd ( $d, $b ), BitAnd ( BitNot ( $d ), $c ) )
                $g = Mod (5*$i+1, 16 )
            ElseIf 32 < $i < 47 Then
                $f = BitXOR ( $b, $c, $d )
                $g = Mod ( 3*$i + 5, 16 )
            Elseif 48 < $i < 63 Then
                $f = BitXOR ( $c, BitOr ( $b, BitNOT ( $d ) ) )
                $g = Mod (7*$i, 16)
            EndIf
            
            $temp = $d
            $d = $c
            $c = $b
            $b = BitRotate ($a + $f + $k[$i] + $w[$g], $r[$i]) + $b
            $a = $temp
        Next
        $h0 = $h0 + $a
        $h1 = $h1 + $b
        $h2 = $h2 + $c
        $h3 = $h3 + $d
    Next
    Return Hex(Abs($h0))&Hex(Abs($h1))&Hex(Abs($h2))&Hex(Abs($h3))
    
EndFunc



Func __MessageInit($message)
    Dim $new [65535]
    Dim $rt[64]
    Local $tmp = 64
    
    For $i = 0 to StringLen ( $message )
        $new[$i] = Asc( StringMid ($message, $i+1, 1 ) )
    Next
    If StringLen ( $message ) < 64 Then
        For $i = 0 to 63
            If $new[$i] <> "" Then
                $rt[$i] = $new[$i]
            Else
                $rt[$i] = 0
            EndIf
        Next
        Return $rt
    EndIf
    
    For $i = 0 to StringLen ( $message )
        If $i >= $tmp+64 Then $tmp = $tmp+64
        
        If $i > 63 Then
            $rt[$i-$tmp] = BitXOR ( $new[$i], $rt[$i-$tmp] )
        Else
            $rt[$i] = $new[$i]
        EndIf
    Next
    Return $rt
EndFunc

Exemple:

This is a test.

A9415AD45B20DCDC0697E205D63352E4

This is a rest.

601174114165187C24F793148F7FB45F

Edited January 3, 2007 by Joke758

[jvanegmond]

Very nice! Too bad MD5 is outdated.

[/dev/null]

Very nice! Too bad MD5 is outdated.

@Manadar: MD5 is outdated? I'm sure you can explain why and in which circumstances...

@Joke758: Can you mathematically prove, that your hash function is cryptographically as strong as MD5 and/or SHA-1? If you cannot do that, I recommend these articles: http://www.securius.com/newsletters/Snake_...Encryption.html AND http://www.schneier.com/crypto-gram-9902.html

Cheers

Kurt

Edited November 15, 2006 by /dev/null

[jvanegmond]

@Manadar: MD5 is outdated? I'm sure you can explain why and in which circumstances...

You just named the reasons why MD5 is outdated. MD5 has inherit flaws. I've only just noticed that he said his script was not exactly MD5, so he may have gotten rid of those flaws. However, it looks more like a rebuild of MD5.