VB中实现MD5加密

;       x As Long, _
                    s As Long, _
                    ac As Long) As Long
    a = LongOverflowAdd4(a, (b And d) Or (c And Not (d)), x, ac)
    a = LongLeftRotate(a, s)
    a = LongOverflowAdd(a, b)
End Function

Private Function HH(a As Long, _
                    b As Long, _
                    c As Long, _
                    d As Long, _
                    x As Long, _
                    s As Long, _
                    ac As Long) As Long
    a = LongOverflowAdd4(a, b Xor c Xor d, x, ac)
    a = LongLeftRotate(a, s)
    a = LongOverflowAdd(a, b)
End Function

Private Function II(a As Long, _
                    b As Long, _
                    c As Long, _
                    d As Long, _
                    x As Long, _
                    s As Long, _
                    ac As Long) As Long
    a = LongOverflowAdd4(a, c Xor (b Or Not (d)), x, ac)
    a = LongLeftRotate(a, s)
    a = LongOverflowAdd(a, b)
End Function

''
'' Rotate a long to the right
''
Function LongLeftRotate(value As Long, bits As Long) As Long
    Dim lngSign As Long
    Dim lngI As Long
    bits = bits Mod 32
    If bits = 0 Then LongLeftRotate = value: Exit Function
    For lngI = 1 To bits
        lngSign = value And &HC0000000
     &nbs