用vb实现DES加解密算法(三)--解密

用vb实现DES加解密算法(三)--解密(11)     '***************************************************K16
    '生成C16,D16
    For i = 0 To 26
        C16(i) = C15(i + Lsi(16))
        D16(i) = D15(i + Lsi(16))
    Next
    C16(27) = C15(0)
    D16(27) = D15(0)
   
    '组合C16,D16成C_D
    For i = 0 To 27
        C_D(i) = C16(i)
        C_D(i + 28) = D16(i)
    Next
   
    'PC_2转换,生成K16
    For i = 0 To 47
        K16(i) = C_D(PC_2(i))
    Next
   
    '**************************************************************************************
   
    '加密过程
'将明文位数扩展为8的倍数
If (UBound(sCode) + 1) Mod 8 > 0 Then ReDim Preserve sCode(((UBound(sCode) + 1) \ 8 + 1) * 8 - 1)
'定义返回密文长度
ReDim bReturn(UBound(sCode))

For j = 0 To UBound(sCode) Step 8
    CopyMemory tempCode(0), sCode(j), 8
    For i = 0 To 7
        BinCode(i * 8 + 0) = (tempCode(i) And &H80) \ &H80
        BinCode(i * 8 + 1) = (tempCode(i) And &H40) \ &H40
        BinCode(i * 8 + 2) = (tempCode(i) And &H20) \ &H20
        BinCode(i * 8 + 3) = (tempCode(i) And &H10) \ &H10
        BinCode(i * 8 + 4) = (tempCode(i) And &H8) \ &H8
        BinCode(i * 8 + 5) = (tempCode(i) And &H4) \ &H4
        BinCode(i * 8 + 6) = (tempCode(i) And &H2) \ &H2