Rijndael クラス

.NET Framework クラス ライブラリ リファレンス

Rijndael クラス

Rijndael 対称暗号化アルゴリズムのすべての実装の継承元となる基本クラスを表します。

名前空間: System.Security.Cryptography
アセンブリ: mscorlib (mscorlib.dll 内)
構文

Visual Basic (宣言)

<ComVisibleAttribute(True)> _
Public MustInherit Class
 Rijndael
    Inherits SymmetricAlgorithm

Visual Basic (使用法)

Dim instance As Rijndael

C#

[ComVisibleAttribute(true)] 
public abstract class Rijndael : SymmetricAlgorithm

C++

[ComVisibleAttribute(true)] 
public ref class Rijndael abstract : public
 SymmetricAlgorithm

J#

/** @attribute ComVisibleAttribute(true) */ 
public abstract class Rijndael extends SymmetricAlgorithm

JScript

ComVisibleAttribute(true) 
public abstract class Rijndael extends
 SymmetricAlgorithm

解説

このアルゴリズムは、128 ビット、192 ビット、256 ビットのキー長をサポートします。

使用例

Rijndael クラスを使用してデータを暗号化し、復号化する方法を次のコード例に示します。

Visual Basic

Imports System.Security.Cryptography
Imports System.Text
Imports System.IO

Module RijndaelSample

    Sub Main()
        Try
            ' Create a new Rijndael object to generate a key
            ' and initialization vector (IV).
            Dim RijndaelAlg As Rijndael = Rijndael.Create

            ' Create a string to encrypt.
            Dim sData As String
 = "Here is some data to encrypt."
            Dim FileName As String
 = "CText.txt"

            ' Encrypt text to a file using the file name, key, and IV.
            EncryptTextToFile(sData, FileName, RijndaelAlg.Key, RijndaelAlg.IV)

            ' Decrypt the text from a file using the file name, key,
 and IV.
            Dim Final As String
 = DecryptTextFromFile(FileName, RijndaelAlg.Key, RijndaelAlg.IV)

            ' Display the decrypted string to the console.
            Console.WriteLine(Final)
        Catch e As Exception
            Console.WriteLine(e.Message)
        End Try

        Console.ReadLine()

    End Sub


    Sub EncryptTextToFile(ByVal Data As
 String, ByVal FileName As
 String, ByVal Key() As Byte, ByVal IV() As Byte)
        Try
            ' Create or open the specified file.
            Dim fStream As FileStream = File.Open(FileName,
 FileMode.OpenOrCreate)

            ' Create a new Rijndael object.
            Dim RijndaelAlg As Rijndael = Rijndael.Create

            ' Create a CryptoStream using the FileStream 
            ' and the passed key and initialization vector (IV).
            Dim cStream As New
 CryptoStream(fStream, _
                                           RijndaelAlg.CreateEncryptor(Key, IV),
 _
                                           CryptoStreamMode.Write)

            ' Create a StreamWriter using the CryptoStream.
            Dim sWriter As New
 StreamWriter(cStream)

            Try

                ' Write the data to the stream 
                ' to encrypt it.
                sWriter.WriteLine(Data)
            Catch e As Exception

                Console.WriteLine("An error occurred: {0}",
 e.Message)

            Finally

                ' Close the streams and
                ' close the file.
                sWriter.Close()
                cStream.Close()
                fStream.Close()

            End Try
        Catch e As CryptographicException
            Console.WriteLine("A Cryptographic error occurred:
 {0}", e.Message)
        Catch e As UnauthorizedAccessException
            Console.WriteLine("A file error occurred: {0}",
 e.Message)
        End Try
    End Sub


    Function DecryptTextFromFile(ByVal FileName
 As String, ByVal Key()
 As Byte, ByVal IV() As Byte) As String
        Try
            ' Create or open the specified file. 
            Dim fStream As FileStream = File.Open(FileName,
 FileMode.OpenOrCreate)

            ' Create a new Rijndael object.
            Dim RijndaelAlg As Rijndael = Rijndael.Create

            ' Create a CryptoStream using the FileStream 
            ' and the passed key and initialization vector (IV).
            Dim cStream As New
 CryptoStream(fStream, _
                                            RijndaelAlg.CreateDecryptor(Key, IV),
 _
                                            CryptoStreamMode.Read)

            ' Create a StreamReader using the CryptoStream.
            Dim sReader As New
 StreamReader(cStream)

            ' Read the data from the stream 
            ' to decrypt it.
            Dim val As String
 = Nothing

            Try

                val = sReader.ReadLine()

            Catch e As Exception
                Console.WriteLine("An Cerror occurred: {0}",
 e.Message)
            Finally
                ' Close the streams and
                ' close the file.
                sReader.Close()
                cStream.Close()
                fStream.Close()


            End Try

            ' Return the string. 
            Return val

        Catch e As CryptographicException
            Console.WriteLine("A Cryptographic error occurred:
 {0}", e.Message)
            Return Nothing
        Catch e As UnauthorizedAccessException
            Console.WriteLine("A file error occurred: {0}",
 e.Message)
            Return Nothing
        End Try
    End Function
End Module

C#

using System;
using System.Security.Cryptography;
using System.Text;
using System.IO;

class RijndaelSample
{

    static void Main()
    {
        try
        {
            // Create a new Rijndael object to generate a key
            // and initialization vector (IV).
            Rijndael RijndaelAlg = Rijndael.Create();

            // Create a string to encrypt.
            string sData = "Here is some data to encrypt.";
            string FileName = "CText.txt";

            // Encrypt text to a file using the file name, key, and
 IV.
            EncryptTextToFile(sData, FileName, RijndaelAlg.Key, RijndaelAlg.IV);

            // Decrypt the text from a file using the file name, key,
 and IV.
            string Final = DecryptTextFromFile(FileName, RijndaelAlg.Key,
 RijndaelAlg.IV);

            // Display the decrypted string to the console.
            Console.WriteLine(Final);
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }

        Console.ReadLine();
    }

    public static void EncryptTextToFile(String
 Data, String FileName, byte[] Key, byte[] IV)
    {
        try
        {
            // Create or open the specified file.
            FileStream fStream = File.Open(FileName, FileMode.OpenOrCreate);

            // Create a new Rijndael object.
            Rijndael RijndaelAlg = Rijndael.Create();

            // Create a CryptoStream using the FileStream 
            // and the passed key and initialization vector (IV).
            CryptoStream cStream = new CryptoStream(fStream,
                RijndaelAlg.CreateEncryptor(Key, IV),
                CryptoStreamMode.Write);

            // Create a StreamWriter using the CryptoStream.
            StreamWriter sWriter = new StreamWriter(cStream);

            try
            {
                // Write the data to the stream 
                // to encrypt it.
                sWriter.WriteLine(Data);
            }
            catch (Exception e)
            {
                Console.WriteLine("An error occurred: {0}", e.Message);
            }
            finally
            {
                // Close the streams and
                // close the file.
                sWriter.Close();
                cStream.Close();
                fStream.Close();
            }
        }
        catch (CryptographicException e)
        {
            Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
        }
        catch (UnauthorizedAccessException e)
        {
            Console.WriteLine("A file error occurred: {0}", e.Message);
        }

    }

    public static string
 DecryptTextFromFile(String FileName, byte[] Key, byte[] IV)
    {
        try
        {
            // Create or open the specified file. 
            FileStream fStream = File.Open(FileName, FileMode.OpenOrCreate);

            // Create a new Rijndael object.
            Rijndael RijndaelAlg = Rijndael.Create();

            // Create a CryptoStream using the FileStream 
            // and the passed key and initialization vector (IV).
            CryptoStream cStream = new CryptoStream(fStream,
                RijndaelAlg.CreateDecryptor(Key, IV),
                CryptoStreamMode.Read);

            // Create a StreamReader using the CryptoStream.
            StreamReader sReader = new StreamReader(cStream);

            string val = null;

            try
            {
                // Read the data from the stream 
                // to decrypt it.
                val = sReader.ReadLine();


            }
            catch (Exception e)
            {
                Console.WriteLine("An error occurred: {0}", e.Message);
            }
            finally
            {

                // Close the streams and
                // close the file.
                sReader.Close();
                cStream.Close();
                fStream.Close();
            }

            // Return the string. 
            return val;
        }
        catch (CryptographicException e)
        {
            Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
            return null;
        }
        catch (UnauthorizedAccessException e)
        {
            Console.WriteLine("A file error occurred: {0}", e.Message);
            return null;
        }
    }
}

継承階層

System.Object
   System.Security.Cryptography.SymmetricAlgorithm
    System.Security.Cryptography.Rijndael
       System.Security.Cryptography.RijndaelManaged

スレッド セーフ

この型の public static (Visual Basic では Shared) メンバはすべて、スレッド セーフです。インスタンス メンバの場合は、スレッド セーフであるとは限りません。

プラットフォーム

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

開発プラットフォームの中には、.NET Framework によってサポートされていないバージョンがあります。サポートされているバージョンについては、「システム要件」を参照してください。

バージョン情報

.NET Framework
サポート対象 : 2.0、1.1、1.0
.NET Compact Framework
サポート対象 : 2.0

参照

関連項目
Rijndael メンバ
System.Security.Cryptography 名前空間
その他の技術情報
暗号サービス