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Rijndael Class

Represents the base class from which all implementations of the Rijndael symmetric encryption algorithm must inherit.

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

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

The Rijndael type exposes the following members.

  NameDescription
Protected methodRijndaelInitializes a new instance of Rijndael.
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  NameDescription
Public propertyBlockSizeGets or sets the block size, in bits, of the cryptographic operation. (Inherited from SymmetricAlgorithm.)
Public propertyFeedbackSizeGets or sets the feedback size, in bits, of the cryptographic operation. (Inherited from SymmetricAlgorithm.)
Public propertyIVGets or sets the initialization vector (IV) for the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
Public propertyKeyGets or sets the secret key for the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
Public propertyKeySizeGets or sets the size, in bits, of the secret key used by the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
Public propertyLegalBlockSizesGets the block sizes, in bits, that are supported by the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
Public propertyLegalKeySizesGets the key sizes, in bits, that are supported by the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
Public propertyModeGets or sets the mode for operation of the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
Public propertyPaddingGets or sets the padding mode used in the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
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  NameDescription
Public methodClearReleases all resources used by the SymmetricAlgorithm class. (Inherited from SymmetricAlgorithm.)
Public methodStatic memberCreateCreates a cryptographic object to perform the Rijndael algorithm.
Public methodStatic memberCreate(String)Creates a cryptographic object to perform the specified implementation of the Rijndael algorithm.
Public methodCreateDecryptorCreates a symmetric decryptor object with the current Key property and initialization vector (IV). (Inherited from SymmetricAlgorithm.)
Public methodCreateDecryptor(Byte(), Byte())When overridden in a derived class, creates a symmetric decryptor object with the specified Key property and initialization vector (IV). (Inherited from SymmetricAlgorithm.)
Public methodCreateEncryptorCreates a symmetric encryptor object with the current Key property and initialization vector (IV). (Inherited from SymmetricAlgorithm.)
Public methodCreateEncryptor(Byte(), Byte())When overridden in a derived class, creates a symmetric encryptor object with the specified Key property and initialization vector (IV). (Inherited from SymmetricAlgorithm.)
Public methodDisposeReleases all resources used by the current instance of the SymmetricAlgorithm class. (Inherited from SymmetricAlgorithm.)
Protected methodDispose(Boolean)Releases the unmanaged resources used by the SymmetricAlgorithm and optionally releases the managed resources. (Inherited from SymmetricAlgorithm.)
Public methodEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGenerateIVWhen overridden in a derived class, generates a random initialization vector (IV) to use for the algorithm. (Inherited from SymmetricAlgorithm.)
Public methodGenerateKeyWhen overridden in a derived class, generates a random key (Key) to use for the algorithm. (Inherited from SymmetricAlgorithm.)
Public methodGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)
Public methodValidKeySizeDetermines whether the specified key size is valid for the current algorithm. (Inherited from SymmetricAlgorithm.)
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  NameDescription
Protected fieldBlockSizeValueRepresents the block size, in bits, of the cryptographic operation. (Inherited from SymmetricAlgorithm.)
Protected fieldFeedbackSizeValueRepresents the feedback size, in bits, of the cryptographic operation. (Inherited from SymmetricAlgorithm.)
Protected fieldIVValueRepresents the initialization vector (IV) for the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
Protected fieldKeySizeValueRepresents the size, in bits, of the secret key used by the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
Protected fieldKeyValueRepresents the secret key for the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
Protected fieldLegalBlockSizesValueSpecifies the block sizes, in bits, that are supported by the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
Protected fieldLegalKeySizesValueSpecifies the key sizes, in bits, that are supported by the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
Protected fieldModeValueRepresents the cipher mode used in the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
Protected fieldPaddingValueRepresents the padding mode used in the symmetric algorithm. (Inherited from SymmetricAlgorithm.)
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This algorithm supports key lengths of 128, 192, or 256 bits.

The Rijndael class is the predecessor of the Aes algorithm. You should use the Aes algorithm instead of Rijndael. For more information, see the entry The Differences Between Rijndael and AES in the .NET Security blog.

The following code example uses the Rijndael class to encrypt and then decrypt data.

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



Class RijndaelExample

    Public Shared Sub Main()
        Try 

            Dim original As String = "Here is some data to encrypt!" 

            ' Create a new instance of the Rijndael 
            ' class.  This generates a new key and initialization  
            ' vector (IV). 
            Using myRijndael = Rijndael.Create()

                ' Encrypt the string to an array of bytes. 
                Dim encrypted As Byte() = EncryptStringToBytes(original, myRijndael.Key, myRijndael.IV)

                ' Decrypt the bytes to a string. 
                Dim roundtrip As String = DecryptStringFromBytes(encrypted, myRijndael.Key, myRijndael.IV)

                'Display the original data and the decrypted data.
                Console.WriteLine("Original:   {0}", original)
                Console.WriteLine("Round Trip: {0}", roundtrip)
            End Using 
        Catch e As Exception
            Console.WriteLine("Error: {0}", e.Message)
        End Try 

    End Sub 'Main

    Shared Function EncryptStringToBytes(ByVal plainText As String, ByVal Key() As Byte, ByVal IV() As Byte) As Byte()
        ' Check arguments. 
        If plainText Is Nothing OrElse plainText.Length <= 0 Then 
            Throw New ArgumentNullException("plainText")
        End If 
        If Key Is Nothing OrElse Key.Length <= 0 Then 
            Throw New ArgumentNullException("Key")
        End If 
        If IV Is Nothing OrElse IV.Length <= 0 Then 
            Throw New ArgumentNullException("Key")
        End If 
        Dim encrypted() As Byte 
        ' Create an Rijndael object 
        ' with the specified key and IV. 
        Using rijAlg = Rijndael.Create()

            rijAlg.Key = Key
            rijAlg.IV = IV

            ' Create a decrytor to perform the stream transform. 
            Dim encryptor As ICryptoTransform = rijAlg.CreateEncryptor(rijAlg.Key, rijAlg.IV)
            ' Create the streams used for encryption. 
            Using msEncrypt As New MemoryStream()
                Using csEncrypt As New CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write)
                    Using swEncrypt As New StreamWriter(csEncrypt)

                        'Write all data to the stream.
                        swEncrypt.Write(plainText)
                    End Using
                    encrypted = msEncrypt.ToArray()
                End Using 
            End Using 
        End Using 

        ' Return the encrypted bytes from the memory stream. 
        Return encrypted

    End Function 'EncryptStringToBytes

    Shared Function DecryptStringFromBytes(ByVal cipherText() As Byte, ByVal Key() As Byte, ByVal IV() As Byte) As String 
        ' Check arguments. 
        If cipherText Is Nothing OrElse cipherText.Length <= 0 Then 
            Throw New ArgumentNullException("cipherText")
        End If 
        If Key Is Nothing OrElse Key.Length <= 0 Then 
            Throw New ArgumentNullException("Key")
        End If 
        If IV Is Nothing OrElse IV.Length <= 0 Then 
            Throw New ArgumentNullException("Key")
        End If 
        ' Declare the string used to hold 
        ' the decrypted text. 
        Dim plaintext As String = Nothing 

        ' Create an Rijndael object 
        ' with the specified key and IV. 
        Using rijAlg = Rijndael.Create()
            rijAlg.Key = Key
            rijAlg.IV = IV

            ' Create a decrytor to perform the stream transform. 
            Dim decryptor As ICryptoTransform = rijAlg.CreateDecryptor(rijAlg.Key, rijAlg.IV)

            ' Create the streams used for decryption. 
            Using msDecrypt As New MemoryStream(cipherText)

                Using csDecrypt As New CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read)

                    Using srDecrypt As New StreamReader(csDecrypt)


                        ' Read the decrypted bytes from the decrypting stream 
                        ' and place them in a string.
                        plaintext = srDecrypt.ReadToEnd()
                    End Using 
                End Using 
            End Using 
        End Using 

        Return plaintext

    End Function 'DecryptStringFromBytes 
End Class

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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