VB版rc4算法

Public Sub main()

Dim key As String

For i = 1 To 16

Randomize

key = key & Chr(Rnd * 255)

Next i

MsgBox RC4(RC4("Welcome To Plindge Studio!", key), key)

End Sub

Public Function RC4(inp As String, key As String) As String

Dim S(0 To 255) As Byte, K(0 To 255) As Byte, i As Long

Dim j As Long, temp As Byte, Y As Byte, t As Long, x As Long

Dim Outp As String

For i = 0 To 255

S(i) = i

Next

j = 1

For i = 0 To 255

If j > Len(key) Then j = 1

K(i) = Asc(Mid(key, j, 1))

j = j + 1

Next i

j = 0

For i = 0 To 255

j = (j + S(i) + K(i)) Mod 256

temp = S(i)

S(i) = S(j)

S(j) = temp

Next i

i = 0

j = 0

For x = 1 To Len(inp)

i = (i + 1) Mod 256

j = (j + S(i)) Mod 256

temp = S(i)

S(i) = S(j)

S(j) = temp

t = (S(i) + (S(j) Mod 256)) Mod 256

Y = S(t)

Outp = Outp & Chr(Asc(Mid(inp, x, 1)) Xor Y)

Next

RC4 = Outp

End Function