AsymmetricKeyExchangeDeformatter Classe

Definição

Representa a classe base da qual derivam todos os desformatadores de troca de chaves assimétrica.Represents the base class from which all asymmetric key exchange deformatters derive.

public ref class AsymmetricKeyExchangeDeformatter abstract
[System.Runtime.Versioning.UnsupportedOSPlatform("browser")]
public abstract class AsymmetricKeyExchangeDeformatter
public abstract class AsymmetricKeyExchangeDeformatter
[System.Runtime.InteropServices.ComVisible(true)]
public abstract class AsymmetricKeyExchangeDeformatter
[<System.Runtime.Versioning.UnsupportedOSPlatform("browser")>]
type AsymmetricKeyExchangeDeformatter = class
type AsymmetricKeyExchangeDeformatter = class
[<System.Runtime.InteropServices.ComVisible(true)>]
type AsymmetricKeyExchangeDeformatter = class
Public MustInherit Class AsymmetricKeyExchangeDeformatter
Herança
AsymmetricKeyExchangeDeformatter
Derivado
Atributos

Exemplos

O exemplo a seguir demonstra como estender a AsymmetricKeyExchangeDeformatter classe.The following example demonstrates how to extend the AsymmetricKeyExchangeDeformatter class.

using System;
using System.Security.Cryptography;

namespace Contoso
{
    public class ContosoDeformatter : AsymmetricKeyExchangeDeformatter
    {
        private RSA rsaKey;

        // Default constructor.
        public ContosoDeformatter(){}

        // Constructor with the public key to use for encryption.
        public ContosoDeformatter(AsymmetricAlgorithm key)
        {
            SetKey(key);
        }

        // Set the public key for encyption operations.
        public override void SetKey(AsymmetricAlgorithm key) {
            if (key != null)
            {
                rsaKey = (RSA)key;
            }
            else
            {
                throw new ArgumentNullException("key");
            }
        }

        // Disallow access to the parameters of the formatter.
        public override String Parameters 
        {
            get { return null; }
            set { ; }
        }

        // Create the encrypted key exchange data from the specified input
        // data. This method uses the RSA class only. To
        // support additional providers or provide custom decryption logic,
        // add logic to this member.
        public override byte[] DecryptKeyExchange(byte[] rgbData) {
            byte[] decryptedBytes = null;

            if (rsaKey != null)
            {
                if (rsaKey is RSA)
                {
                    RSA rsa = (RSA)rsaKey;

                    decryptedBytes = rsa.Decrypt(rgbData, RSAEncryptionPadding.OaepSHA1);
                }
                // Add custom decryption logic here.
            }
            else
            {
                throw new CryptographicUnexpectedOperationException(
                    "Cryptography_MissingKey");
            }

            return decryptedBytes;
        }
    }
}
//
// This code example produces the following output:
//
// Data to encrypt : Sample Contoso encryption application.
// Encrypted data: Khasdf-3248&$%23
// Data decrypted : Sample Contoso encryption application.
// 
// This sample completed successfully; press Enter to exit.
Imports System.Security.Cryptography

Namespace Contoso
    Public Class ContosoDeformatter
        Inherits AsymmetricKeyExchangeDeformatter

        Private rsaKey As RSA

        ' Default constructor.
        Public Sub New()

        End Sub

        ' Constructor with the public key to use for encryption.
        Public Sub New(ByVal key As AsymmetricAlgorithm)
            SetKey(key)
        End Sub

        ' Set the public key for encyption operations.
        Public Overrides Sub SetKey(ByVal key As AsymmetricAlgorithm)
            If (Not key Is Nothing) Then
                rsaKey = CType(key, RSA)
            Else
                Throw New ArgumentNullException("key")
            End If
        End Sub

        ' Disallow access to the parameters of the formatter.
        Public Overrides ReadOnly Property Parameters() As String
            Get
                Return Nothing
            End Get
            Set(ByVal Value As String)

            End Set
        End Property

        ' Create the encrypted key exchange data from the specified input
        ' data. This method uses the RSA class only. To
        ' support additional providers or provide custom decryption logic,
        ' add logic to this member.
        Public Overrides Function DecryptKeyExchange(
            ByVal rgbData() As Byte) As Byte()

            Dim decryptedBytes() As Byte

            If (Not rsaKey Is Nothing) Then
                If (TypeOf (rsaKey) Is RSA) Then
                    Dim rsa As RSA
                    rsa = CType(rsaKey, RSA)

                    decryptedBytes = rsa.Decrypt(rgbData, RSAEncryptionPadding.OaepSHA1)
                End If

                ' Add custom decryption logic here.

            Else
                Throw New CryptographicUnexpectedOperationException(
                    "Cryptography_MissingKey")
            End If

            Return decryptedBytes
        End Function

    End Class
End Namespace
'
' This code example produces the following output:
'
' Data to encrypt : Sample Contoso encryption application.
' Encrypted data: Kh34dfg-(*&834d+3
' Data decrypted : Sample Contoso encryption application.
' 
' This sample completed successfully; press Exit to continue.

Comentários

Os desformatadores de troca de chave assimétrica descriptografam dados de troca de chaves.Asymmetric key exchange deformatters decrypt key exchange data.

A troca de chaves permite que um remetente crie informações secretas, como dados aleatórios que podem ser usados como uma chave em um algoritmo de criptografia simétrica e use criptografia para enviá-la ao destinatário pretendido.Key exchange allows a sender to create secret information, such as random data that can be used as a key in a symmetric encryption algorithm, and use encryption to send it to the intended recipient.

Cuidado

É altamente recomendável que você não tente criar seu próprio método de troca de chaves a partir da funcionalidade básica fornecida, pois muitos detalhes da operação devem ser executados cuidadosamente para que a troca de chaves seja bem-sucedida.It is highly recommended that you not attempt to create your own key exchange method from the basic functionality provided, because many details of the operation must be performed carefully in order for the key exchange to be successful.

Construtores

AsymmetricKeyExchangeDeformatter()

Inicializa uma nova instância de AsymmetricKeyExchangeDeformatter.Initializes a new instance of AsymmetricKeyExchangeDeformatter.

Propriedades

Parameters

Quando substituído em uma classe derivada, obtém ou define os parâmetros para a troca de chaves assimétrica.When overridden in a derived class, gets or sets the parameters for the asymmetric key exchange.

Métodos

DecryptKeyExchange(Byte[])

Quando substituído em uma classe derivada, extrai as informações de segredo dos dados de troca de chaves criptografados.When overridden in a derived class, extracts secret information from the encrypted key exchange data.

Equals(Object)

Determina se o objeto especificado é igual ao objeto atual.Determines whether the specified object is equal to the current object.

(Herdado de Object)
GetHashCode()

Serve como a função de hash padrão.Serves as the default hash function.

(Herdado de Object)
GetType()

Obtém o Type da instância atual.Gets the Type of the current instance.

(Herdado de Object)
MemberwiseClone()

Cria uma cópia superficial do Object atual.Creates a shallow copy of the current Object.

(Herdado de Object)
SetKey(AsymmetricAlgorithm)

Quando substituído em uma classe derivada, define a chave privada a ser usada para descriptografar as informações secretas.When overridden in a derived class, sets the private key to use for decrypting the secret information.

ToString()

Retorna uma cadeia de caracteres que representa o objeto atual.Returns a string that represents the current object.

(Herdado de Object)

Aplica-se a