Datei verschlüsseln und entschlüsseln

[Th3_Cr4xX]

Kann für nen Crypter ganz nützlich sein :)

Credits: Dr. Peter Flsicher



ption Explicit On
Option Infer On
Option Strict On

Imports System.Xml.Serialization
Imports System.IO
Imports System.Security.Cryptography

Module Module1

Sub Main()
Try
'
' Teil 1 Datei verschlüsseln und ablegen
'
Using fs As New FileStream("c:\temp\x1.x", FileMode.Open)
' verschlüsseln
SaveEncrypted("c:\temp\x2.x", fs)
End Using
'
' Teil 2 Datei wieder entschlüsseln
'
Using fs As New FileStream("c:\temp\x3.x", FileMode.Create)
' entschlüsseln
LoadEncrypted("c:\temp\x2.x", fs)
End Using
'
Console.WriteLine("Vorgang abgeschlossen")
Catch ex As Exception
Console.WriteLine(ex.Message)
End Try
'
Console.ReadLine()
End Sub

''' <summary>
''' Schlüssel für Ver- und Entschlüsselung
''' </summary>
''' <remarks></remarks>
Dim desKey() As Byte = {1, 2, 3, 4, 5, 6, 7, 8}
Dim desIV() As Byte = {1, 2, 3, 4, 5, 6, 7, 9}

''' <summary>
''' XML-Datenstrom verschlüsseln und in Datei ablegen
''' </summary>
''' <param name="filename">Dateiname für Ablage</param>
''' <param name="str">IO-Stream (z.B. MemoryStream) mit Daten</param>
''' <remarks></remarks>
Private Sub SaveEncrypted(ByVal filename As String, ByVal str As Stream)
Dim fout As FileStream = Nothing
Dim encStream As CryptoStream = Nothing
Try
'Create the file streams to handle the output files.
fout = New FileStream(filename, FileMode.OpenOrCreate, FileAccess.Write)
fout.SetLength(0)
'Create variables to help with read and write.
Dim bin(99) As Byte 'This is intermediate storage for the encryption.
Dim rdlen As Long = 0 'This is the total number of bytes written.
Dim totlen As Long = str.Length 'Total length of the input file.
Dim lng As Integer ' This is the number of bytes to be written at a time.
'Creates the default implementation, which is RijndaelManaged.
Dim des As New DESCryptoServiceProvider
encStream = New CryptoStream(fout, des.CreateEncryptor(desKey, desIV), CryptoStreamMode.Write)
'Read from the input file, then encrypt and write to the output file.
str.Position = 0
While rdlen < totlen
lng = str.Read(bin, 0, bin.GetUpperBound(0))
encStream.Write(bin, 0, lng)
rdlen = Convert.ToInt32(rdlen + lng)
End While
Catch ex As Exception
MsgBox(ex.Message)
Finally
If encStream IsNot Nothing Then encStream.Dispose()
If fout IsNot Nothing Then fout.Close()
End Try
End Sub

''' <summary>
''' XML-Datenstrom aus Datei laden und entschlüsseln
''' </summary>
''' <param name="filename">Dateiname zum Einlesen</param>
''' <param name="str">IO-Stream (z.B. MemoryStream) mit Daten</param>
''' <remarks></remarks>
Private Sub LoadEncrypted(ByVal filename As String, ByVal str As Stream)
Dim fin As System.IO.FileStream = Nothing
Dim decStream As CryptoStream = Nothing
Try
fin = New FileStream(filename, FileMode.Open, FileAccess.Read)
'Create variables to help with read and write.
Dim bin(10000) As Byte ' This is intermediate storage for the encryption.
Dim rdlen As Long = 0 'This is the total number of bytes written.
Dim totlen As Long = fin.Length 'Total length of the input file.
Dim lng As Integer ' This is the number of bytes to be written at a time.
'Creates the default implementation, which is RijndaelManaged.
Dim des As New DESCryptoServiceProvider
decStream = New CryptoStream(fin, des.CreateDecryptor(desKey, desIV), CryptoStreamMode.Read)
'Read from the input file, then encrypt and write to the output file.
lng = decStream.Read(bin, 0, bin.GetUpperBound(0) + 1)
While lng > 0
str.Write(bin, 0, lng)
rdlen = Convert.ToInt32(rdlen + lng)
lng = decStream.Read(bin, 0, bin.GetUpperBound(0) + 1)
End While
Catch ex As Exception
MsgBox(ex.Message)
Finally
If decStream IsNot Nothing Then decStream.Dispose()
If fin IsNot Nothing Then fin.Dispose()
End Try
End Sub

End Module