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' Initialize the class
' This must be called before a digest calculation is started
'
Public Sub MD5Init()
ByteCounter = 0
State(1) = UnsignedToLong(1732584193#)
State(2) = UnsignedToLong(4023233417#)
State(3) = UnsignedToLong(2562383102#)
State(4) = UnsignedToLong(271733878#)
End Sub
'
' MD5 Final
'
Public Sub MD5Final()
Dim dblBits As Double
Dim padding(72) As Byte
Dim lngBytesBuffered As Long
padding(0) = &H80
dblBits = ByteCounter * 8
' Pad out
lngBytesBuffered = ByteCounter Mod 64
If lngBytesBuffered <= 56 Then
MD5Update 56 - lngBytesBuffered, padding
Else
MD5Update 120 - ByteCounter, padding
End If
padding(0) = UnsignedToLong(dblBits) And &HFF&
padding(1) = UnsignedToLong(dblBits) \ 256 And &HFF&
padding(2) = UnsignedToLong(dblBits) \ 65536 And &HFF&
padding(3) = UnsignedToLong(dblBits) \ 16777216 And &HFF&
padding(4) = 0
padding(5) = 0
padding(6) = 0
padding(7) = 0
MD5Update 8, padding
End Sub
'
' Break up input stream into 64 byte chunks
'
Public Sub MD5Update(InputLen As Long, InputBuffer() As Byte)
Dim II As Integer
Dim I As Integer
Dim J As Integer
Dim K As Integer
Dim lngBufferedBytes As Long
Dim lngBufferRemaining As Long
Dim lngRem As Long
lngBufferedBytes = ByteCounter Mod 64
lngBufferRemaining = 64 - lngBufferedBytes
ByteCounter = ByteCounter + InputLen
' Use up old buffer results first
If InputLen >= lngBufferRemaining Then
For II = 0 To lngBufferRemaining - 1
ByteBuffer(lngBufferedBytes + II) = InputBuffer(II)
Next II
MD5Transform ByteBuffer
lngRem = (InputLen) Mod 64
' The transfer is a multiple of 64 lets do some transformations
For I = lngBufferRemaining To InputLen - II - lngRem Step 64
For J = 0 To 63
ByteBuffer(J) = InputBuffer(I + J)
Next J
MD5Transform ByteBuffer
Next I
lngBufferedBytes = 0
Else
I = 0
End If
' Buffer any remaining input
For K = 0 To InputLen - I - 1
ByteBuffer(lngBufferedBytes + K) = InputBuffer(I + K)
Next K
End Sub
'
' MD5 Transform
'
Private Sub MD5Transform(Buffer() As Byte)
Dim x(16) As Long
Dim a As Long
Dim b As Long
Dim c As Long
Dim d As Long
a = State(1)
b = State(2)
c = State(3)
d = State(4)
Decode 64, x, Buffer
' Round 1
FF a, b, c, d, x(0), S11, -680876936
FF d, a, b, c, x(1), S12, -389564586
FF c, d, a, b, x(2), S13, 606105819
FF b, c, d, a, x(3), S14, -1044525330
FF a, b, c, d, x(4), S11, -176418897
FF d, a, b, c, x(5), S12, 1200080426
FF c, d, a, b, x(6), S13, -1473231341
FF b, c, d, a, x(7), S14, -45705983
FF a, b, c, d, x(8), S11, 1770035416
FF d, a, b, c, x(9), S12, -1958414417
FF c, d, a, b, x(10), S13, -42063
FF b, c, d, a, x(11), S14, -1990404162
FF a, b, c, d, x(12), S11, 1804603682
FF d, a, b, c, x(13), S12, -40341101
FF c, d, a, b, x(14), S13, -1502002290
FF b, c, d, a, x(15), S14, 1236535329
' Round 2
GG a, b, c, d, x(1), S21, -165796510
GG d, a, b, c, x(6), S22, -1069501632
GG c, d, a, b, x(11), S23, 643717713
GG b, c, d, a, x(0), S24, -373897302
GG a, b, c, d, x(5), S21, -701558691
GG d, a, b, c, x(10), S22, 38016083
GG c, d, a, b, x(15), S23, -660478335
GG b, c, d, a, x(4), S24, -405537848
GG a, b, c, d, x(9), S21, 568446438
GG d, a, b, c, x(14), S22, -1019803690
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