Locked Encryptación RC4

[Expermicid]

Library to Import

 

[lenguaje=vb.net]Imports System.Text[/lenguaje]

 

Function RC4

 

[lenguaje=vb.net]Public Shared Function rc4(ByVal message As String, ByVal password As String) As String

 

Dim i As Integer = 0

Dim j As Integer = 0

Dim cipher As New StringBuilder

Dim returnCipher As String = String.Empty

 

Dim sbox As Integer() = New Integer(256) {}

Dim key As Integer() = New Integer(256) {}

 

Dim intLength As Integer = password.Length

 

Dim a As Integer = 0

While a <= 255

 

Dim ctmp As Char = (password.Substring((a Mod intLength), 1).ToCharArray()(0))

 

key(a) = Microsoft.VisualBasic.Strings.Asc(ctmp)

sbox(a) = a

System.Math.Max(System.Threading.Interlocked.Increment(a), a - 1)

End While

 

Dim x As Integer = 0

 

Dim b As Integer = 0

While b <= 255

x = (x + sbox(;) + key(;)) Mod 256

Dim tempSwap As Integer = sbox(;)

sbox(B) = sbox(x)

sbox(x) = tempSwap

System.Math.Max(System.Threading.Interlocked.Increment(B), b - 1)

End While

 

a = 1

 

While a <= message.Length

 

Dim itmp As Integer = 0

 

i = (i + 1) Mod 256

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

itmp = sbox(i)

sbox(i) = sbox(j)

sbox(j) = itmp

 

Dim k As Integer = sbox((sbox(i) + sbox(j)) Mod 256)

 

Dim ctmp As Char = message.Substring(a - 1, 1).ToCharArray()(0)

 

itmp = Asc(ctmp)

 

Dim cipherby As Integer = itmp Xor k

 

cipher.Append(Chr(cipherby))

System.Math.Max(System.Threading.Interlocked.Increment(a), a - 1)

End While

 

returnCipher = cipher.ToString

cipher.Length = 0

 

Return returnCipher

 

End Function[/lenguaje]

 

Using

 

[lenguaje=vb.net]rc4("Text","password")[/lenguaje]

 

Saludos :)

Edited February 16, 2014 by Expermicid