MD5 Hashing not quite working out ...

[GremlinSA]

I have a requirement to MD5Hash certain parts of a file .. (so i need some control over what gets hashed)..

So i looked up the specs ...

Pseudo Code
'//Note: All variables are unsigned 32 bits and wrap modulo 2^32 when calculating
'var int[64] r, k

'//r specifies the per-round shift amounts
'r[ 0..15] := {7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22}
'r[16..31] := {5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20}
'r[32..47] := {4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23}
'r[48..63] := {6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21}

'//Use binary integer part of the sines of integers (Radians) as constants:
'for i from 0 to 63
' k[i] := floor(abs(sin(i + 1)) × (2 pow 32))

'//Initialize variables:
'var int h0 := 0x01234567
'var int h1 := 0x89ABCDEF
'var int h2 := 0xFEDCBA98
'var int h3 := 0x76543210

'//Pre-processing:
'append "1" bit to message
'append "0" bits until message length in bits ≡ 448 (mod 512)
' 56 (mod 64)
'append bit /* bit, not byte */ length of unpadded message as 64-bit little-endian integer to message

'//Process the message in successive 512-bit chunks:
'for each 512-bit chunk of message
' break chunk into sixteen 32-bit little-endian words w[i], 0 ≤ i ≤ 15

' //Initialize hash value for this chunk:
' var int a := h0
' var int b := h1
' var int c := h2
' var int d := h3

' //Main loop:
' for i from 0 to 63
' if 0 ≤ i ≤ 15 then
' f := (b and c) or ((not b) and d)
' g := i
' else if 16 ≤ i ≤ 31
' f := (d and b) or ((not d) and c)
' g := (5×i + 1) mod 16
' else if 32 ≤ i ≤ 47
' f := b xor c xor d
' g := (3×i + 5) mod 16
' else if 48 ≤ i ≤ 63
' f := c xor (b or (not d))
' g := (7×i) mod 16

' temp := d
' d := c
' c := b
' b := b + leftrotate((a + f + k[i] + w[g]) , r[i])
' a := temp

' //Add this chunk's hash to result so far:
' h0 := h0 + a
' h1 := h1 + b
' h2 := h2 + c
' h3 := h3 + d

'var int digest := h0 append h1 append h2 append h3 //(expressed as little-endian)

' //leftrotate function definition
' leftrotate (x, c)
' return (x << c) or (x >> (32-c));

I've pretty much got most of the core of this working.. However when running a few test strings i'm getting the wrong hash back ..

running MD5 on ("") should give "d41d8cd98f00b204e9800998ecf8427e" however i'm getting "E0BA2C792CFD07E92768A891C861AB11"

I've previously done a CRC 16 Module from simular pseudo code, that worked 100%, but i'm batteling with this one for several days now..

Public Class MD5Hash
    Private R() As UInt32
    Private K() As UInt32
    Private H() As UInt32
    Private Pre() As UInt32
    Private A() As UInt32
    Private _Size As Integer
    Private _Current As Integer

    Public Sub New()
        InitK()
        InitR()
    End Sub

    Public Sub Reset(ByVal FinSize As Integer)
        ReDim H(3)
        ReDim Pre(3)
        ReDim A(3)
        'ReDim Block(15)
        _Size = FinSize
        _Current = 0

        H(0) = &H1234567&
        H(1) = &H89ABCDEF&
        H(2) = &HFEDCBA98&
        H(3) = &H76543210&

    End Sub

    Private Sub InitR()
        Dim S() As String
        Dim TmpInt As Integer
        ReDim R(63)

        S = Split("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 ", ",")

        For TmpInt = 0 To 63
            R(TmpInt) = Val(S(TmpInt))
        Next
    End Sub

    Private Sub InitK()
        Dim TmpInt As Integer
        Dim S() As String
        S = Split("D76AA478,E8C7B756,242070DB,C1BDCEEE,F57C0FAF,4787C62A,A8304613,FD469501," & _
                  "698098D8,8B44F7AF,FFFF5BB1,895CD7BE,6B901122,FD987193,A679438E,49B40821," & _
                  "F61E2562,C040B340,265E5A51,E9B6C7AA,D62F105D,02441453,D8A1E681,E7D3FBC8," & _
                  "21E1CDE6,C33707D6,F4D50D87,455A14ED,A9E3E905,FCEFA3F8,676F02D9,8D2A4C8A," & _
                  "FFFA3942,8771F681,6D9D6122,FDE5380C,A4BEEA44,4BDECFA9,F6BB4B60,BEBFBC70," & _
                  "289B7EC6,EAA127FA,D4EF3085,04881D05,D9D4D039,E6DB99E5,1FA27CF8,C4AC5665," & _ 
                  "F4292244,432AFF97,AB9423A7,FC93A039,655B59C3,8F0CCC92,FFEFF47D,85845DD1," & _ 
                  "6FA87E4F,FE2CE6E0,A3014314,4E0811A1,F7537E82,BD3AF235,2AD7D2BB,EB86D391", ",")

        ReDim K(63)
        For TmpInt = 0 To 63
            K(TmpInt) = CUint32(S(TmpInt))
        Next
    End Sub

    Private Function LeftRotate(ByVal InVal As UInt32, ByVal Bits As Integer) As UInt32
        Dim TmpInt As Integer
        For TmpInt = 1 To Bits
            If InVal And &H80000000& Then
                InVal = (InVal << 1) Or &H1
            Else
                InVal = (InVal << 1)
            End If
        Next
        Return InVal
    End Function

    Private Function F1(ByVal X As UInt32, ByVal Y As UInt32, ByVal Z As UInt32) As UInt32
        Return (X And Y) Or (Not (X) And Z)
    End Function

    Private Function F2(ByVal X As UInt32, ByVal Y As UInt32, ByVal Z As UInt32) As UInt32
        Return (X And Z) Or (Not (Y) And Z)
    End Function

    Private Function F3(ByVal X As UInt32, ByVal Y As UInt32, ByVal Z As UInt32) As UInt32
        Return X Xor Y Xor Z
    End Function

    Private Function F4(ByVal X As UInt32, ByVal Y As UInt32, ByVal Z As UInt32) As UInt32
        Return Y Xor (X Or (Not Z))
    End Function

    Private Function Hex8(ByVal Value As UInt32) As String
        Dim s As String

        s = Hex(Value)
        Do While (Len(s) < 8)
            s = "0" & s
        Loop
        Return s
    End Function

    Private Function Hex16(ByVal Value As UInt64) As String
        Dim s As String

        s = Hex(Value)
        Do While (Len(s) < 16)
            s = "0" & s
        Loop
        Return s

    End Function

    Private Function CUint32(ByVal Hex As String) As UInt32
        Dim tmpInt As Integer

        CUint32 = 0
        For tmpInt = 0 To Hex.Length - 1
            CUint32 = (CUint32 * &H10) + Val("&H" & Hex.Substring(tmpInt, 1))
        Next
    End Function

    Public ReadOnly Property GetHash() As String
        Get
            Return Hex8(H(0)) & Hex8(H(1)) & Hex8(H(2)) & Hex8(H(3))
        End Get
    End Property

    Private Sub Core(ByVal Block() As UInt32)
        Dim Tmpint As Integer
        Dim TmpUint As UInt32
        Dim F As UInt32
        Dim G As UInt32
        Dim Tmp1Int64 As Int64
        Dim Tmp2Int64 As Int64


        If Block.Length <> 16 Then
            MsgBox("MD5 Data Object Incorect Size")
            Exit Sub
        End If
        For Tmpint = 0 To 63
            Select Case Tmpint
                Case 0 To 15
                    F = F1(A(1), A(2), A(3))
                    G = Tmpint
                Case 16 To 31
                    F = F2(A(1), A(2), A(3))
                    G = (5 * Tmpint + 1) Mod 16
                Case 32 To 47
                    F = F3(A(1), A(2), A(3))
                    G = (3 * Tmpint + 5) Mod 16
                Case 48 To 63
                    F = F4(A(1), A(2), A(3))
                    G = (7 * Tmpint) Mod 16

            End Select
            TmpUint = A(3)
            A(3) = A(2)
            A(2) = A(1)
            Tmp1Int64 = F
            Tmp1Int64 += A(0)
            Tmp1Int64 += K(Tmpint)
            Tmp1Int64 += Block(G)
            Tmp1Int64 = Tmp1Int64 And &HFFFFFFFF&
            Tmp2Int64 = A(1)
            Tmp2Int64 += LeftRotate(CUInt(Tmp1Int64), R(Tmpint))
            A(1) = Tmp2Int64 And &HFFFFFFFF&
            A(0) = TmpUint
        Next
    End Sub

    Public Sub MD5(ByVal Data() As UInt32)
        Dim TmpInt64 As Int64
        Dim TmpInt As Integer
        If Data.Length <> 16 Then
            MsgBox("MD5 Data Object Incorect Size")
            Exit Sub
        End If
        A(0) = H(0)
        A(1) = H(1)
        A(2) = H(2)
        A(3) = H(3)
        Core(Data)
        For TmpInt = 0 To 3
            TmpInt64 = H(TmpInt)
            TmpInt64 += A(TmpInt)
            H(TmpInt) = TmpInt64 And &HFFFFFFFF
        Next

    End Sub

    Public Sub MD5(ByVal Data() As Byte)
        Dim DataInt32() As UInt32
        Dim Tmpint As Integer
        Dim Tmpint2 As Integer
        If Data.Length <> 64 Then
            MsgBox("MD5 Data Object Incorect Size")
            Exit Sub
        End If

        ReDim DataInt32(15)
        For Tmpint = 0 To 15
            For Tmpint2 = 0 To 3
                DataInt32(Tmpint) = (DataInt32(Tmpint) * &H100) + Data(Tmpint * 4 + Tmpint2)
            Next
        Next
        MD5(DataInt32)
    End Sub

End Class

Could someone please check where i'm going wrong here ...

Thanks
Gremmy....

[javajawa]

If you think It would be of help, I could post the VB6 MD5 code for you to compare against. But I can't see that being of much use.

[GremlinSA]

If you've got VB6 MD5 Hashing code .. Please, I'd like to use it to compare...

Thanks..

[javajawa]

Here we go...
Enjoy!

[GremlinSA]

Okay i found where i'm going wrong .. ..

I forgot about Little endian and big endian .. I'm working almost everything in big ...

Ouch ...

Time to sort it all out...

Gremmy

[GremlinSA]

Ya hoo ... I got it sorted ..

Thank javajawa, that module did help, i now get the correct MD5 Hash for the test strings...

Now to finilise the complete MD5 Class....

Gremmy....