一个利用随机数加密字串的算法

众香之主

一个利用随机数加密字串的算法

首先这个算法没什么特殊之处，只是怕以后找不到，所以放到了这上面        每个字节加密后有6种结果（占两个字节，如果需要大于6种的话，就要多用1个字节，即占3 个字节），也就是说如果字串占n个字节的话，可能产生的结果为6的n次方个，这个算法破解的强度不大，大家可以完善一下： ´窗体上一个按钮，两个listbox Option Explicit Private Sub Command1_Click()     Dim i As Long     Dim s As String     For i = 1 To 100         s = encode("这是一个测试 hello world")         List1.AddItem s         s = decode(s)         List2.AddItem s     Next End Sub Private Function encode(ByVal s As String) As String ´加密     If Len(s) = 0 Then Exit Function     Dim buff() As Byte     buff = StrConv(s, vbFromUnicode)     Dim i As Long     Dim j As Byte     Dim k As Byte, m As Byte     Dim mstr As String     mstr = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789abcdefghijklmnopqrstuvwxyz"     Dim outs As String     i = UBound(buff) + 1     outs = Space(2 * i)     Dim temps As String     For i = 0 To UBound(buff)         Randomize Time         j = CByte(5 * (Math.Rnd()) + 0) ´最大产生的随机数只能是5，不能再大了,再大的话，就要多用一个字节         buff(i) = buff(i) Xor j         k = buff(i) Mod Len(mstr)         m = buff(i) \ Len(mstr)         m = m * 2 ^ 3 + j         temps = Mid(mstr, k + 1, 1) + Mid(mstr, m + 1, 1)         Mid(outs, 2 * i + 1, 2) = temps      Next      encode = outs End Function Private Function decode(ByVal s As String) As String ´解密     On Error GoTo myERR     Dim i As Long     Dim j As Byte     Dim k As Byte     Dim m As Byte     Dim mstr As String     mstr = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789abcdefghijklmnopqrstuvwxyz"     Dim t1 As String, t2 As String     Dim buff() As Byte     Dim n As Long     n = 0     For i = 1 To Len(s) Step 2         t1 = Mid(s, i, 1)         t2 = Mid(s, i + 1, 1)         k = InStr(1, mstr, t1) - 1         m = InStr(1, mstr, t2) - 1         j = m \ 2 ^ 3         m = m - j * 2 ^ 3         ReDim Preserve buff(n)         buff(n) = j * Len(mstr) + k         buff(n) = buff(n) Xor m         n = n + 1      Next      decode = StrConv(buff, vbUnicode)      Exit Function myERR:      decode = "" End Function