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TripleDES-Klasse

Stellt die Basisklasse für TripleDES-Algorithmen (Triple Data Encryption Standard) dar, von der alle TripleDES-Implementierungen abgeleitet werden müssen.

Namespace: System.Security.Cryptography
Assembly: mscorlib (in mscorlib.dll)

Syntax

'Declaration
<ComVisibleAttribute(True)> _
Public MustInherit Class TripleDES
    Inherits SymmetricAlgorithm
'Usage
Dim instance As TripleDES
[ComVisibleAttribute(true)] 
public abstract class TripleDES : SymmetricAlgorithm
[ComVisibleAttribute(true)] 
public ref class TripleDES abstract : public SymmetricAlgorithm
/** @attribute ComVisibleAttribute(true) */ 
public abstract class TripleDES extends SymmetricAlgorithm
ComVisibleAttribute(true) 
public abstract class TripleDES extends SymmetricAlgorithm

Hinweise

TripleDES verwendet drei aufeinander folgende Iterationen des DES-Algorithmus. Es können entweder zwei oder drei 56-Bit-Schlüssel verwendet werden.

Dieser Algorithmus unterstützt eine Schlüssellänge von 128 bis 192 Bits und eine Inkrementierung um je 64 Bits.

Beispiel

In der Methode des folgenden Codebeispiels wird TripleDESCryptoServiceProvider mit dem angegebenen Schlüssel (Key) und dem angegebenen Intialisierungsvektor (IV) verwendet, um die von inName angegebene Datei zu verschlüsseln. Anschließend wird das verschlüsselte Ergebnis in die durch outName angegebene Datei ausgegeben.

Private Shared Sub EncryptData(inName As String, outName As String, _
   tdesKey() As Byte, tdesIV() As Byte)
   
    'Create the file streams to handle the input and output files.
    Dim fin As New FileStream(inName, FileMode.Open, FileAccess.Read)
    Dim fout As New FileStream(outName, FileMode.OpenOrCreate, _
       FileAccess.Write)
    fout.SetLength(0)
        
    'Create variables to help with read and write.
    Dim bin(100) 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 'This is the total length of the input file.
    Dim len As Integer 'This is the number of bytes to be written at a time.
    Dim tdes As New TripleDESCryptoServiceProvider()
    Dim encStream As New CryptoStream(fout, _
       tdes.CreateEncryptor(tdesKey, tdesIV), CryptoStreamMode.Write)
        
    Console.WriteLine("Encrypting...")
        
    'Read from the input file, then encrypt and write to the output file.
    While rdlen < totlen
        len = fin.Read(bin, 0, 100)
        encStream.Write(bin, 0, len)
        rdlen = rdlen + len
        Console.WriteLine("{0} bytes processed", rdlen)
    End While
        
    encStream.Close()
End Sub
private static void EncryptData(String inName, String outName, byte[] tdesKey, byte[] tdesIV)
{    
    //Create the file streams to handle the input and output files.
    FileStream fin = new FileStream(inName, FileMode.Open, FileAccess.Read);
    FileStream fout = new FileStream(outName, FileMode.OpenOrCreate, FileAccess.Write);
    fout.SetLength(0);
      
    //Create variables to help with read and write.
    byte[] bin = new byte[100]; //This is intermediate storage for the encryption.
    long rdlen = 0;              //This is the total number of bytes written.
    long totlen = fin.Length;    //This is the total length of the input file.
    int len;                     //This is the number of bytes to be written at a time.

    TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();          
    CryptoStream encStream = new CryptoStream(fout, tdes.CreateEncryptor(tdesKey, tdesIV), CryptoStreamMode.Write);
               
    Console.WriteLine("Encrypting...");

    //Read from the input file, then encrypt and write to the output file.
    while(rdlen < totlen)
    {
        len = fin.Read(bin, 0, 100);
        encStream.Write(bin, 0, len);
        rdlen = rdlen + len;
        Console.WriteLine("{0} bytes processed", rdlen);
    }

    encStream.Close();                     
}
void EncryptData( String^ inName, String^ outName, array<Byte>^tdesKey, array<Byte>^tdesIV )
{
   
   //Create the file streams to handle the input and output files.
   FileStream^ fin = gcnew FileStream( inName,FileMode::Open,FileAccess::Read );
   FileStream^ fout = gcnew FileStream( outName,FileMode::OpenOrCreate,FileAccess::Write );
   fout->SetLength( 0 );
   
   //Create variables to help with read and write.
   array<Byte>^bin = gcnew array<Byte>(100);
   long rdlen = 0; //This is the total number of bytes written.

   long totlen = (long)fin->Length; //This is the total length of the input file.

   int len; //This is the number of bytes to be written at a time.

   TripleDESCryptoServiceProvider^ tdes = gcnew TripleDESCryptoServiceProvider;
   CryptoStream^ encStream = gcnew CryptoStream( fout,tdes->CreateEncryptor( tdesKey, tdesIV ),CryptoStreamMode::Write );
   Console::WriteLine( "Encrypting..." );
   
   //Read from the input file, then encrypt and write to the output file.
   while ( rdlen < totlen )
   {
      len = fin->Read( bin, 0, 100 );
      encStream->Write( bin, 0, len );
      rdlen = rdlen + len;
      Console::WriteLine( "{0} bytes processed", rdlen );
   }

   encStream->Close();
}
private static void EncryptData(String inName, String outName, 
    ubyte tdesKey[],ubyte tdesIV[])
{
    //Create the file streams to handle the input and output files.
    FileStream fin = new FileStream(inName, FileMode.Open,
        FileAccess.Read);
    FileStream fout = new FileStream(outName, FileMode.OpenOrCreate,
        FileAccess.Write);
    fout.SetLength(0);

    //Create variables to help with read and write.
    ubyte bin[] = new ubyte[100];//This is intermediate storage for the 
                                 //encryption.
    long rdlen = 0; //This is the total number of bytes written.
    long totlen = fin.get_Length(); //This is the total length 
                                    //of the input file.
    int len; //This is the number of bytes to be written at a time.

    TripleDESCryptoServiceProvider tdes =
            new TripleDESCryptoServiceProvider();
    CryptoStream encStream = new CryptoStream(fout,
        tdes.CreateEncryptor(tdesKey, tdesIV), CryptoStreamMode.Write);
    Console.WriteLine("Encrypting...");

    //Read from the input file, then encrypt and write to the output file.
    while ((rdlen < totlen)) {
        len = fin.Read(bin, 0, 100);
        encStream.Write(bin, 0, len);
        rdlen = rdlen + len;
        Console.WriteLine("{0} bytes processed",
            System.Convert.ToString(rdlen));
    }
    encStream.Close();
} //EncryptData

Die Entschlüsselung kann auf die gleiche Weise erfolgen. Verwenden Sie hierbei CreateDecryptor statt CreateEncryptor. Beim Entschlüsseln der Datei müssen derselbe Schlüssel (Key) und derselbe Initialisierungsvektor (IV) verwendet werden wie beim Verschlüsseln.

Vererbungshierarchie

System.Object
   System.Security.Cryptography.SymmetricAlgorithm
    System.Security.Cryptography.TripleDES
       System.Security.Cryptography.TripleDESCryptoServiceProvider

Threadsicherheit

Alle öffentlichen statischen (Shared in Visual Basic) Member dieses Typs sind threadsicher. Bei Instanzmembern ist die Threadsicherheit nicht gewährleistet.

Plattformen

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile für Pocket PC, Windows Mobile für Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.

Versionsinformationen

.NET Framework

Unterstützt in: 2.0, 1.1, 1.0

.NET Compact Framework

Unterstützt in: 2.0

Siehe auch

Referenz

TripleDES-Member
System.Security.Cryptography-Namespace

Weitere Ressourcen

Kryptografische Dienste