EncryptedKey Klasse

Definition

Namespace:

System.Security.Cryptography.Xml

Assembly:

System.Security.Cryptography.Xml.dll

Paket:

System.Security.Cryptography.Xml v8.0.0

Quelle:

EncryptedKey.cs

Stellt das <EncryptedKey>-Element bei XML-Verschlüsselung dar. Diese Klasse kann nicht vererbt werden.

public ref class EncryptedKey sealed : System::Security::Cryptography::Xml::EncryptedType

public sealed class EncryptedKey : System.Security.Cryptography.Xml.EncryptedType

type EncryptedKey = class
    inherit EncryptedType

Public NotInheritable Class EncryptedKey
Inherits EncryptedType

Vererbung

Object

EncryptedType

EncryptedKey

Beispiele

Im folgenden Beispiel wird veranschaulicht, wie ein XML-Element mithilfe der EncryptedKey -Klasse verschlüsselt und entschlüsselt wird. In diesem Beispiel werden dann die Werte verschiedener Eigenschaften der EncryptedKey -Klasse für die Konsole angezeigt.

using System;
using System.Xml;
using System.Security.Cryptography;
using System.Security.Cryptography.Xml;

class Program
{
    static void Main(string[] args)
    {

        // Create an XmlDocument object.
        XmlDocument xmlDoc = new XmlDocument();

        // Load an XML file into the XmlDocument object.
        try
        {
            xmlDoc.PreserveWhitespace = true;
            xmlDoc.Load("test.xml");
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }

        // Create a new RSA key.  This key will encrypt a symmetric key,
        // which will then be imbedded in the XML document.
        RSA rsaKey = RSA.Create();

        try
        {
            // Encrypt the "creditcard" element.
            Encrypt(xmlDoc, "creditcard", rsaKey, "rsaKey");

            // Inspect the EncryptedKey element.
            InspectElement(xmlDoc);

            // Decrypt the "creditcard" element.
            Decrypt(xmlDoc, rsaKey, "rsaKey");
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }
        finally
        {
            // Clear the RSA key.
            rsaKey.Clear();
        }
    }

    public static void Encrypt(XmlDocument Doc, string ElementToEncrypt, RSA Alg, string KeyName)
    {
        // Check the arguments.
        if (Doc == null)
            throw new ArgumentNullException("Doc");
        if (ElementToEncrypt == null)
            throw new ArgumentNullException("ElementToEncrypt");
        if (Alg == null)
            throw new ArgumentNullException("Alg");

        ////////////////////////////////////////////////
        // Find the specified element in the XmlDocument
        // object and create a new XmlElemnt object.
        ////////////////////////////////////////////////

        XmlElement elementToEncrypt = Doc.GetElementsByTagName(ElementToEncrypt)[0] as XmlElement;

        // Throw an XmlException if the element was not found.
        if (elementToEncrypt == null)
        {
            throw new XmlException("The specified element was not found");
        }

        //////////////////////////////////////////////////
        // Create a new instance of the EncryptedXml class
        // and use it to encrypt the XmlElement with the
        // a new random symmetric key.
        //////////////////////////////////////////////////

        // Create a 256 bit Aes key.
        Aes sessionKey = Aes.Create();
        sessionKey.KeySize = 256;

        EncryptedXml eXml = new EncryptedXml();

        byte[] encryptedElement = eXml.EncryptData(elementToEncrypt, sessionKey, false);

        ////////////////////////////////////////////////
        // Construct an EncryptedData object and populate
        // it with the desired encryption information.
        ////////////////////////////////////////////////

        EncryptedData edElement = new EncryptedData();
        edElement.Type = EncryptedXml.XmlEncElementUrl;

        // Create an EncryptionMethod element so that the
        // receiver knows which algorithm to use for decryption.

        edElement.EncryptionMethod = new EncryptionMethod(EncryptedXml.XmlEncAES256Url);

        // Encrypt the session key and add it to an EncryptedKey element.
        EncryptedKey ek = new EncryptedKey();

        byte[] encryptedKey = EncryptedXml.EncryptKey(sessionKey.Key, Alg, false);

        ek.CipherData = new CipherData(encryptedKey);

        ek.EncryptionMethod = new EncryptionMethod(EncryptedXml.XmlEncRSA15Url);

        // Set the KeyInfo element to specify the
        // name of the RSA key.

        // Create a new KeyInfo element.
        edElement.KeyInfo = new KeyInfo();

        // Create a new KeyInfoName element.
        KeyInfoName kin = new KeyInfoName();

        // Specify a name for the key.
        kin.Value = KeyName;

        // Add the KeyInfoName element to the
        // EncryptedKey object.
        ek.KeyInfo.AddClause(kin);

        // Add the encrypted key to the
        // EncryptedData object.

        edElement.KeyInfo.AddClause(new KeyInfoEncryptedKey(ek));

        // Add the encrypted element data to the
        // EncryptedData object.
        edElement.CipherData.CipherValue = encryptedElement;

        ////////////////////////////////////////////////////
        // Replace the element from the original XmlDocument
        // object with the EncryptedData element.
        ////////////////////////////////////////////////////

        EncryptedXml.ReplaceElement(elementToEncrypt, edElement, false);
    }

    public static void Decrypt(XmlDocument Doc, RSA Alg, string KeyName)
    {
        // Check the arguments.
        if (Doc == null)
            throw new ArgumentNullException("Doc");
        if (Alg == null)
            throw new ArgumentNullException("Alg");
        if (KeyName == null)
            throw new ArgumentNullException("KeyName");

        // Create a new EncryptedXml object.
        EncryptedXml exml = new EncryptedXml(Doc);

        // Add a key-name mapping.
        // This method can only decrypt documents
        // that present the specified key name.
        exml.AddKeyNameMapping(KeyName, Alg);

        // Decrypt the element.
        exml.DecryptDocument();
    }

    static void InspectElement(XmlDocument Doc)
    {
        // Get the EncryptedKey element from the XMLDocument object.
        XmlElement encryptedKey = Doc.GetElementsByTagName("EncryptedKey")[0] as XmlElement;

        // Create a new EncryptedKey object.
        EncryptedKey k = new EncryptedKey();

        // Load the XML from the document to
        // initialize the EncryptedKey object.
        k.LoadXml(encryptedKey);

        // Display the properties.
        // Most values are Null by default.
        Console.WriteLine("EncryptedKey.KeyInfo: " + k.KeyInfo.GetXml().InnerXml);
        Console.WriteLine("EncryptedKey.Id: " + k.Id);
        Console.WriteLine("EncryptedKey.CarriedKeyName: " + k.CarriedKeyName);
        Console.WriteLine("EncryptedKey.CipherData: " + k.CipherData.GetXml().InnerXml);
        Console.WriteLine("EncryptedKey.Encoding: " + k.Encoding);
        Console.WriteLine("EncryptedKey.EncryptionMethod: " + k.EncryptionMethod.GetXml().InnerXml);
        if (k.EncryptionProperties.Count >= 1)
        {
            Console.WriteLine("EncryptedKey.EncryptionProperties: " + k.EncryptionProperties[0].GetXml().InnerXml);
        }
        Console.WriteLine("EncryptedKey.MimeType: " + k.MimeType);
        Console.WriteLine("EncryptedKey.Recipient: " + k.Recipient);

        if (k.ReferenceList.Count >= 1)
        {
            Console.WriteLine("EncryptedKey.ReferenceList: " + k.ReferenceList[0].GetXml().InnerXml);
        }
    }
}

Imports System.Xml
Imports System.Security.Cryptography
Imports System.Security.Cryptography.Xml



Module Program

    Sub Main(ByVal args() As String)

        ' Create an XmlDocument object.
        Dim xmlDoc As New XmlDocument()

        ' Load an XML file into the XmlDocument object.
        Try
            xmlDoc.PreserveWhitespace = True
            xmlDoc.Load("test.xml")
        Catch e As Exception
            Console.WriteLine(e.Message)
        End Try

        ' Create a new RSA key.  This key will encrypt a symmetric key,
        ' which will then be imbedded in the XML document.  
        Dim rsaKey As RSA = RSA.Create()


        Try
            ' Encrypt the "creditcard" element.
            Encrypt(xmlDoc, "creditcard", rsaKey, "rsaKey")

            ' Inspect the EncryptedKey element.
            InspectElement(xmlDoc)

            ' Decrypt the "creditcard" element.
            Decrypt(xmlDoc, rsaKey, "rsaKey")

        Catch e As Exception
            Console.WriteLine(e.Message)
        Finally
            ' Clear the RSA key.
            rsaKey.Clear()
        End Try

    End Sub


    Sub Encrypt(ByVal Doc As XmlDocument, ByVal ElementToEncryptParam As String, ByVal Alg As RSA, ByVal KeyName As String)
        ' Check the arguments.  
        If Doc Is Nothing Then
            Throw New ArgumentNullException("Doc")
        End If
        If ElementToEncryptParam Is Nothing Then
            Throw New ArgumentNullException("ElementToEncrypt")
        End If
        If Alg Is Nothing Then
            Throw New ArgumentNullException("Alg")
        End If
        ''''''''''''''''''''''''''''''''''''''''''''''''''''
        ' Find the specified element in the XmlDocument
        ' object and create a new XmlElemnt object.
        ''''''''''''''''''''''''''''''''''''''''''''''''''''
        Dim elementToEncrypt As XmlElement = Doc.GetElementsByTagName(ElementToEncryptParam)(0)


        ' Throw an XmlException if the element was not found.
        If elementToEncrypt Is Nothing Then
            Throw New XmlException("The specified element was not found")
        End If

        ''''''''''''''''''''''''''''''''''''''''''''''''''''
        ' Create a new instance of the EncryptedXml class 
        ' and use it to encrypt the XmlElement with the 
        ' a new random symmetric key.
        ''''''''''''''''''''''''''''''''''''''''''''''''''''
        ' Create a 256 bit Aes key.
        Dim sessionKey As Aes = Aes.Create()
        sessionKey.KeySize = 256

        Dim eXml As New EncryptedXml()

        Dim encryptedElement As Byte() = eXml.EncryptData(elementToEncrypt, sessionKey, False)

        ''''''''''''''''''''''''''''''''''''''''''''''''''''
        ' Construct an EncryptedData object and populate
        ' it with the desired encryption information.
        ''''''''''''''''''''''''''''''''''''''''''''''''''''

        Dim edElement As New EncryptedData()
        edElement.Type = EncryptedXml.XmlEncElementUrl

        ' Create an EncryptionMethod element so that the 
        ' receiver knows which algorithm to use for decryption.
        edElement.EncryptionMethod = New EncryptionMethod(EncryptedXml.XmlEncAES256Url)

        ' Encrypt the session key and add it to an EncryptedKey element.
        Dim ek As New EncryptedKey()

        Dim encryptedKey As Byte() = EncryptedXml.EncryptKey(sessionKey.Key, Alg, False)

        ek.CipherData = New CipherData(encryptedKey)

        ek.EncryptionMethod = New EncryptionMethod(EncryptedXml.XmlEncRSA15Url)

        ' Set the KeyInfo element to specify the
        ' name of the RSA key.
        ' Create a new KeyInfo element.
        edElement.KeyInfo = New KeyInfo()

        ' Create a new KeyInfoName element.
        Dim kin As New KeyInfoName()

        ' Specify a name for the key.
        kin.Value = KeyName

        ' Add the KeyInfoName element to the 
        ' EncryptedKey object.
        ek.KeyInfo.AddClause(kin)

        ' Add the encrypted key to the 
        ' EncryptedData object.
        edElement.KeyInfo.AddClause(New KeyInfoEncryptedKey(ek))

        ' Add the encrypted element data to the 
        ' EncryptedData object.
        edElement.CipherData.CipherValue = encryptedElement

        ''''''''''''''''''''''''''''''''''''''''''''''''''''
        ' Replace the element from the original XmlDocument
        ' object with the EncryptedData element.
        ''''''''''''''''''''''''''''''''''''''''''''''''''''
        EncryptedXml.ReplaceElement(elementToEncrypt, edElement, False)

    End Sub


    Sub Decrypt(ByVal Doc As XmlDocument, ByVal Alg As RSA, ByVal KeyName As String)
        ' Check the arguments.  
        If Doc Is Nothing Then
            Throw New ArgumentNullException("Doc")
        End If
        If Alg Is Nothing Then
            Throw New ArgumentNullException("Alg")
        End If
        If KeyName Is Nothing Then
            Throw New ArgumentNullException("KeyName")
        End If
        ' Create a new EncryptedXml object.
        Dim exml As New EncryptedXml(Doc)

        ' Add a key-name mapping.
        ' This method can only decrypt documents
        ' that present the specified key name.
        exml.AddKeyNameMapping(KeyName, Alg)

        ' Decrypt the element.
        exml.DecryptDocument()

    End Sub


    Sub InspectElement(ByVal Doc As XmlDocument)
        ' Get the EncryptedKey element from the XMLDocument object.
        Dim encryptedKey As XmlElement = Doc.GetElementsByTagName("EncryptedKey")(0)

        ' Create a new EncryptedKey object.
        Dim k As New EncryptedKey()

        ' Load the XML from the document to
        ' initialize the EncryptedKey object.
        k.LoadXml(encryptedKey)

        ' Display the properties.
        ' Most values are Null by default.
        Console.WriteLine("EncryptedKey.KeyInfo: " + k.KeyInfo.GetXml().InnerXml)
        Console.WriteLine("EncryptedKey.Id: " + k.Id)
        Console.WriteLine("EncryptedKey.CarriedKeyName: " + k.CarriedKeyName)
        Console.WriteLine("EncryptedKey.CipherData: " + k.CipherData.GetXml().InnerXml)
        Console.WriteLine("EncryptedKey.Encoding: " + k.Encoding)
        Console.WriteLine("EncryptedKey.EncryptionMethod: " + k.EncryptionMethod.GetXml().InnerXml)
        If k.EncryptionProperties.Count >= 1 Then
            Console.WriteLine("EncryptedKey.EncryptionProperties: " + k.EncryptionProperties(0).GetXml().InnerXml)
        End If
        Console.WriteLine("EncryptedKey.MimeType: " + k.MimeType)
        Console.WriteLine("EncryptedKey.Recipient: " + k.Recipient)

        If k.ReferenceList.Count >= 1 Then
            Console.WriteLine("EncryptedKey.ReferenceList: " + k.ReferenceList(0).GetXml().InnerXml)
        End If

    End Sub
End Module

Hinweise

Diese Klasse stellt das Element in der <EncryptedKey> XML-Verschlüsselung dar. Das <EncryptedKey> -Element wird zum Senden von Verschlüsselungsschlüsseln verwendet. Es kann in einem eigenständigen XML-Dokument erstellt, in einem Anwendungsdokument platziert werden oder sich als untergeordnetes Element eines Elements in einem <EncryptedData><KeyInfo> Element befinden. Der Schlüsselwert wird immer mit dem Empfänger verschlüsselt. Wenn <EncryptedKey> entschlüsselt wird, wird der resultierende Schlüssel dem <EncryptionMethod> Algorithmus ohne zusätzliche Verarbeitung zur Verfügung gestellt.

Das <EncryptedKey> -Element ähnelt dem <EncryptedData> -Element der EncryptedData -Klasse, mit der Ausnahme, dass die verschlüsselten Daten immer ein Schlüsselwert sind.

Konstruktoren

EncryptedKey()

Initialisiert eine neue Instanz der EncryptedKey-Klasse.

Eigenschaften

CarriedKeyName	Ruft das optionale <CarriedKeyName>-Element in XML-Verschlüsselung ab oder legt dieses fest.
CipherData	Ruft den CipherData-Wert für eine Instanz einer EncryptedType-Klasse ab oder legt diesen fest. (Geerbt von EncryptedType)
Encoding	Ruft das Encoding-Attribut einer EncryptedType-Instanz in XML-Verschlüsselung ab oder legt dieses fest. (Geerbt von EncryptedType)
EncryptionMethod	Ruft das <EncryptionMethod>-Element für die XML-Verschlüsselung ab oder legt dieses fest. (Geerbt von EncryptedType)
EncryptionProperties	Ruft das <EncryptionProperties>-Element in XML-Verschlüsselung ab oder legt dieses fest. (Geerbt von EncryptedType)
Id	Ruft das Id-Attribut einer EncryptedType-Instanz in XML-Verschlüsselung ab oder legt dieses fest. (Geerbt von EncryptedType)
KeyInfo	Ruft das <KeyInfo>-Element in XML-Verschlüsselung ab oder legt dieses fest. (Geerbt von EncryptedType)
MimeType	Ruft das MimeType-Attribut einer EncryptedType-Instanz in XML-Verschlüsselung ab oder legt dieses fest. (Geerbt von EncryptedType)
Recipient	Ruft das optionale Recipient-Attribut in XML-Verschlüsselung ab oder legt dieses fest.
ReferenceList	Ruft das <ReferenceList>-Element in XML-Verschlüsselung ab oder legt dieses fest.
Type	Ruft das Type-Attribut einer EncryptedType-Instanz in XML-Verschlüsselung ab oder legt dieses fest. (Geerbt von EncryptedType)

Methoden

AddProperty(EncryptionProperty)	Fügt dem <EncryptionProperty>-Element im aktuellen EncryptedType-Objekt in XML-Verschlüsselung ein untergeordnetes <EncryptedProperties>-Element hinzu. (Geerbt von EncryptedType)
AddReference(DataReference)	Fügt dem <ReferenceList>-Element ein <DataReference>-Element hinzu.
AddReference(KeyReference)	Fügt dem <ReferenceList>-Element ein <KeyReference>-Element hinzu.
Equals(Object)	Bestimmt, ob das angegebene Objekt gleich dem aktuellen Objekt ist. (Geerbt von Object)
GetHashCode()	Fungiert als Standardhashfunktion. (Geerbt von Object)
GetType()	Ruft den Type der aktuellen Instanz ab. (Geerbt von Object)
GetXml()	Gibt die XML-Darstellung des EncryptedKey-Objekts zurück.
LoadXml(XmlElement)	Lädt die angegebenen XML-Informationen in XML-Verschlüsselung in das <EncryptedKey>-Element.
MemberwiseClone()	Erstellt eine flache Kopie des aktuellen Object. (Geerbt von Object)
ToString()	Gibt eine Zeichenfolge zurück, die das aktuelle Objekt darstellt. (Geerbt von Object)