RSAPKCS1KeyExchangeDeformatter クラス

定義

PKCS #1 キー交換データを復号化します。Decrypts the PKCS #1 key exchange data.

public ref class RSAPKCS1KeyExchangeDeformatter : System::Security::Cryptography::AsymmetricKeyExchangeDeformatter
[System.Runtime.InteropServices.ComVisible(true)]
public class RSAPKCS1KeyExchangeDeformatter : System.Security.Cryptography.AsymmetricKeyExchangeDeformatter
type RSAPKCS1KeyExchangeDeformatter = class
    inherit AsymmetricKeyExchangeDeformatter
Public Class RSAPKCS1KeyExchangeDeformatter
Inherits AsymmetricKeyExchangeDeformatter
継承
RSAPKCS1KeyExchangeDeformatter
属性

次の例は、クラスを使用RSAPKCS1KeyExchangeDeformatterして、メッセージの復号化に使用する交換キーを再作成する方法を示しています。The following example shows how to use the RSAPKCS1KeyExchangeDeformatter class to recreate an exchange key to be used to decrypt a message.

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


class Alice
{
    public static void Main(string[] args)
    {
        using (Bob bob = new Bob())
        {
            using (RSACryptoServiceProvider rsaKey = new RSACryptoServiceProvider())
            {
                // Get Bob's public key
                rsaKey.ImportCspBlob(bob.key);
                byte[] encryptedSessionKey = null;
                byte[] encryptedMessage = null;
                byte[] iv = null;
                Send(rsaKey, "Secret message", out iv, out encryptedSessionKey, out encryptedMessage);
                bob.Receive(iv, encryptedSessionKey, encryptedMessage);
            }
        }
    }

    private static void Send(RSA key, string secretMessage, out byte[] iv, out byte[] encryptedSessionKey, out byte[] encryptedMessage)
    {
        using (Aes aes = new AesCryptoServiceProvider())
        {
            iv = aes.IV;

            // Encrypt the session key
            RSAPKCS1KeyExchangeFormatter keyFormatter = new RSAPKCS1KeyExchangeFormatter(key);
            encryptedSessionKey = keyFormatter.CreateKeyExchange(aes.Key, typeof(Aes));

            // Encrypt the message
            using (MemoryStream ciphertext = new MemoryStream())
            using (CryptoStream cs = new CryptoStream(ciphertext, aes.CreateEncryptor(), CryptoStreamMode.Write))
            {
                byte[] plaintextMessage = Encoding.UTF8.GetBytes(secretMessage);
                cs.Write(plaintextMessage, 0, plaintextMessage.Length);
                cs.Close();

                encryptedMessage = ciphertext.ToArray();
            }
        }
    }

}
public class Bob : IDisposable
{
    public byte[] key;
    private RSACryptoServiceProvider rsaKey = new RSACryptoServiceProvider();
    public Bob()
    {
        key = rsaKey.ExportCspBlob(false);
    }
    public void Receive(byte[] iv, byte[] encryptedSessionKey, byte[] encryptedMessage)
    {

        using (Aes aes = new AesCryptoServiceProvider())
        {
            aes.IV = iv;

            // Decrypt the session key
            RSAPKCS1KeyExchangeDeformatter keyDeformatter = new RSAPKCS1KeyExchangeDeformatter(rsaKey);
            aes.Key = keyDeformatter.DecryptKeyExchange(encryptedSessionKey);

            // Decrypt the message
            using (MemoryStream plaintext = new MemoryStream())
            using (CryptoStream cs = new CryptoStream(plaintext, aes.CreateDecryptor(), CryptoStreamMode.Write))
            {
                cs.Write(encryptedMessage, 0, encryptedMessage.Length);
                cs.Close();

                string message = Encoding.UTF8.GetString(plaintext.ToArray());
                Console.WriteLine(message);
            }
        }
    }
    public void Dispose()
    {
        rsaKey.Dispose();
    }
}
Imports System.IO
Imports System.Security.Cryptography
Imports System.Text




Class Alice

    Public Shared Sub Main(ByVal args() As String)
        Dim bob As New Bob()
        Try
            Dim rsaKey As New RSACryptoServiceProvider()
            Try
                ' Get Bob's public key
                rsaKey.ImportCspBlob(bob.key)
                Dim encryptedSessionKey As Byte() = Nothing
                Dim encryptedMessage As Byte() = Nothing
                Dim iv As Byte() = Nothing
                Send(rsaKey, "Secret message", iv, encryptedSessionKey, encryptedMessage)
                bob.Receive(iv, encryptedSessionKey, encryptedMessage)
            Finally
                rsaKey.Dispose()
            End Try
        Finally
            bob.Dispose()
        End Try

    End Sub


    Private Shared Sub Send(ByVal key As RSA, ByVal secretMessage As String, ByRef iv() As Byte, ByRef encryptedSessionKey() As Byte, ByRef encryptedMessage() As Byte)
        Dim aes = New AesCryptoServiceProvider()
        Try
            iv = aes.IV

            ' Encrypt the session key
            Dim keyFormatter As New RSAPKCS1KeyExchangeFormatter(key)
            encryptedSessionKey = keyFormatter.CreateKeyExchange(aes.Key, GetType(Aes))

            ' Encrypt the message
            Dim ciphertext As New MemoryStream()
            Try
                Dim cs As New CryptoStream(ciphertext, aes.CreateEncryptor(), CryptoStreamMode.Write)
                Try
                    Dim plaintextMessage As Byte() = Encoding.UTF8.GetBytes(secretMessage)
                    cs.Write(plaintextMessage, 0, plaintextMessage.Length)
                    cs.Close()

                    encryptedMessage = ciphertext.ToArray()
                Finally
                    cs.Dispose()
                End Try
            Finally
                ciphertext.Dispose()
            End Try
        Finally
            aes.Dispose()
        End Try

    End Sub
End Class

Public Class Bob
    Implements IDisposable
    Public key() As Byte
    Private rsaKey As New RSACryptoServiceProvider()

    Public Sub New()
        key = rsaKey.ExportCspBlob(False)

    End Sub

    Public Sub Receive(ByVal iv() As Byte, ByVal encryptedSessionKey() As Byte, ByVal encryptedMessage() As Byte)

        Dim aes = New AesCryptoServiceProvider()
        Try
            aes.IV = iv

            ' Decrypt the session key
            Dim keyDeformatter As New RSAPKCS1KeyExchangeDeformatter(rsaKey)
            aes.Key = keyDeformatter.DecryptKeyExchange(encryptedSessionKey)

            ' Decrypt the message
            Dim plaintext As New MemoryStream()
            Try
                Dim cs As New CryptoStream(plaintext, aes.CreateDecryptor(), CryptoStreamMode.Write)
                Try
                    cs.Write(encryptedMessage, 0, encryptedMessage.Length)
                    cs.Close()

                    Dim message As String = Encoding.UTF8.GetString(plaintext.ToArray())
                    Console.WriteLine(message)
                Finally
                    cs.Dispose()
                End Try
            Finally
                plaintext.Dispose()
            End Try
        Finally
            aes.Dispose()
        End Try

    End Sub
    Public Overloads Sub Dispose() Implements IDisposable.Dispose
        rsaKey.Dispose()
    End Sub
End Class

注釈

キー交換を使用すると、送信者はシークレット情報 (対称暗号化アルゴリズムでキーとして使用できるランダムなデータなど) を作成し、暗号化を使用して目的の受信者に送信することができます。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.

アルゴリズムRSAPKCS1KeyExchangeFormatterを使用してキー交換メッセージをRSA作成するには、を使用します。Use RSAPKCS1KeyExchangeFormatter to create the key exchange message using the RSA algorithm.

注意事項

キー交換を成功させるには、操作の詳細情報を慎重に実行する必要があるため、提供されている基本的な機能から独自のキー交換メソッドを作成しないことを強くお勧めします。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.

コンストラクター

RSAPKCS1KeyExchangeDeformatter()

RSAPKCS1KeyExchangeDeformatter クラスの新しいインスタンスを初期化します。Initializes a new instance of the RSAPKCS1KeyExchangeDeformatter class.

RSAPKCS1KeyExchangeDeformatter(AsymmetricAlgorithm)

指定したキーで、RSAPKCS1KeyExchangeDeformatter クラスの新しいインスタンスを初期化します。Initializes a new instance of the RSAPKCS1KeyExchangeDeformatter class with the specified key.

プロパティ

Parameters

PKCS #1 キー交換のパラメーターを取得します。Gets the parameters for the PKCS #1 key exchange.

RNG

キー交換の作成に使用する乱数ジェネレーター アルゴリズムを取得または設定します。Gets or sets the random number generator algorithm to use in the creation of the key exchange.

メソッド

DecryptKeyExchange(Byte[])

暗号化されたキー交換データから秘密情報を抽出します。Extracts secret information from the encrypted key exchange data.

Equals(Object)

指定されたオブジェクトが現在のオブジェクトと等しいかどうかを判定します。Determines whether the specified object is equal to the current object.

(継承元 Object)
GetHashCode()

既定のハッシュ関数として機能します。Serves as the default hash function.

(継承元 Object)
GetType()

現在のインスタンスの Type を取得します。Gets the Type of the current instance.

(継承元 Object)
MemberwiseClone()

現在の Object の簡易コピーを作成します。Creates a shallow copy of the current Object.

(継承元 Object)
SetKey(AsymmetricAlgorithm)

秘密情報の暗号化解除に使用する秘密キーを設定します。Sets the private key to use for decrypting the secret information.

ToString()

現在のオブジェクトを表す string を返します。Returns a string that represents the current object.

(継承元 Object)

適用対象

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