RijndaelManaged Classe

Definição

public ref class RijndaelManaged sealed : System::Security::Cryptography::Rijndael

public sealed class RijndaelManaged : System.Security.Cryptography.Rijndael

[System.Runtime.InteropServices.ComVisible(true)]
public sealed class RijndaelManaged : System.Security.Cryptography.Rijndael

type RijndaelManaged = class
    inherit Rijndael

[<System.Runtime.InteropServices.ComVisible(true)>]
type RijndaelManaged = class
    inherit Rijndael

Public NotInheritable Class RijndaelManaged
Inherits Rijndael

Herança

Object

SymmetricAlgorithm

Rijndael

RijndaelManaged

Atributos

ComVisibleAttribute

Exemplos

O exemplo a seguir demonstra como criptografar e descriptografar dados de exemplo usando a RijndaelManaged classe.

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

namespace RijndaelManaged_Example
{
    class RijndaelExample
    {
        public static void Main()
        {
            try
            {

                string original = "Here is some data to encrypt!";

                // Create a new instance of the RijndaelManaged
                // class.  This generates a new key and initialization
                // vector (IV).
                using (RijndaelManaged myRijndael = new RijndaelManaged())
                {

                    myRijndael.GenerateKey();
                    myRijndael.GenerateIV();
                    // Encrypt the string to an array of bytes.
                    byte[] encrypted = EncryptStringToBytes(original, myRijndael.Key, myRijndael.IV);

                    // Decrypt the bytes to a string.
                    string roundtrip = 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);
                }
            }
            catch (Exception e)
            {
                Console.WriteLine("Error: {0}", e.Message);
            }
        }
        static byte[] EncryptStringToBytes(string plainText, byte[] Key, byte[] IV)
        {
            // Check arguments.
            if (plainText == null || plainText.Length <= 0)
                throw new ArgumentNullException("plainText");
            if (Key == null || Key.Length <= 0)
                throw new ArgumentNullException("Key");
            if (IV == null || IV.Length <= 0)
                throw new ArgumentNullException("IV");
            byte[] encrypted;
            // Create an RijndaelManaged object
            // with the specified key and IV.
            using (RijndaelManaged rijAlg = new RijndaelManaged())
            {
                rijAlg.Key = Key;
                rijAlg.IV = IV;

                // Create an encryptor to perform the stream transform.
                ICryptoTransform encryptor = rijAlg.CreateEncryptor(rijAlg.Key, rijAlg.IV);

                // Create the streams used for encryption.
                using (MemoryStream msEncrypt = new MemoryStream())
                {
                    using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                    {
                        using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
                        {

                            //Write all data to the stream.
                            swEncrypt.Write(plainText);
                        }
                    }

                    encrypted = msEncrypt.ToArray();
                }
            }

            // Return the encrypted bytes from the memory stream.
            return encrypted;
        }

        static string DecryptStringFromBytes(byte[] cipherText, byte[] Key, byte[] IV)
        {
            // Check arguments.
            if (cipherText == null || cipherText.Length <= 0)
                throw new ArgumentNullException("cipherText");
            if (Key == null || Key.Length <= 0)
                throw new ArgumentNullException("Key");
            if (IV == null || IV.Length <= 0)
                throw new ArgumentNullException("IV");

            // Declare the string used to hold
            // the decrypted text.
            string plaintext = null;

            // Create an RijndaelManaged object
            // with the specified key and IV.
            using (RijndaelManaged rijAlg = new RijndaelManaged())
            {
                rijAlg.Key = Key;
                rijAlg.IV = IV;

                // Create a decryptor to perform the stream transform.
                ICryptoTransform decryptor = rijAlg.CreateDecryptor(rijAlg.Key, rijAlg.IV);

                // Create the streams used for decryption.
                using (MemoryStream msDecrypt = new MemoryStream(cipherText))
                {
                    using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                    {
                        using (StreamReader srDecrypt = new StreamReader(csDecrypt))
                        {
                            // Read the decrypted bytes from the decrypting stream
                            // and place them in a string.
                            plaintext = srDecrypt.ReadToEnd();
                        }
                    }
                }
            }

            return plaintext;
        }
    }
}

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 RijndaelManaged
            ' class.  This generates a new key and initialization 
            ' vector (IV).
            Using myRijndael As New RijndaelManaged()
            
                myRijndael.GenerateKey()
                myRijndael.GenerateIV()

                ' 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

    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("IV")
        End If
        Dim encrypted() As Byte
        
        ' Create an RijndaelManaged object
        ' with the specified key and IV.
        Using rijAlg As New RijndaelManaged()

            rijAlg.Key = Key
            rijAlg.IV = IV

            ' Create an encryptor 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("IV")
        End If
        ' Declare the string used to hold
        ' the decrypted text.
        Dim plaintext As String = Nothing

        ' Create an RijndaelManaged object
        ' with the specified key and IV.
        Using rijAlg As New RijndaelManaged
            rijAlg.Key = Key
            rijAlg.IV = IV

            ' Create a decryptor 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

Comentários

Esse algoritmo dá suporte a comprimentos de chave de 128, 192 ou 256 bits; padrão para 256 bits. No .NET Framework, esse algoritmo dá suporte a tamanhos de bloco de 128, 192 ou 256 bits, com o padrão sendo 128 bits (Aes compatível). No .NET Core, ele é igual ao AES e dá suporte apenas a um tamanho de bloco de 128 bits.

Confira também

• Serviços criptográficos