EncryptedType Class

Represents the abstract base class from which the classes EncryptedData and EncryptedKey derive.

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

[HostProtectionAttribute(SecurityAction.LinkDemand, MayLeakOnAbort = true)]
public abstract class EncryptedType

The EncryptedType type exposes the following members.

  NameDescription
Protected methodEncryptedTypeInitializes a new instance of the EncryptedType class.
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  NameDescription
Public propertyCipherDataGets or sets the CipherData value for an instance of an EncryptedType class.
Public propertyEncodingGets or sets the Encoding attribute of an EncryptedType instance in XML encryption.
Public propertyEncryptionMethodGets or sets the <EncryptionMethod> element for XML encryption.
Public propertyEncryptionPropertiesGets or sets the <EncryptionProperties> element in XML encryption.
Public propertyIdGets or sets the Id attribute of an EncryptedType instance in XML encryption.
Public propertyKeyInfoGets of sets the <KeyInfo> element in XML encryption.
Public propertyMimeTypeGets or sets the MimeType attribute of an EncryptedType instance in XML encryption.
Public propertyTypeGets or sets the Type attribute of an EncryptedType instance in XML encryption.
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  NameDescription
Public methodAddPropertyAdds an <EncryptionProperty> child element to the <EncryptedProperties> element in the current EncryptedType object in XML encryption.
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 methodGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodGetXmlReturns the XML representation of the EncryptedType object.
Public methodLoadXmlLoads XML information into the <EncryptedType> element in XML encryption.
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)
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The EncryptedType class represents the abstract base class from which the classes EncryptedData and EncryptedKey derive. These two classes contain the actual encrypted data or key information in XML encryption. To comply with XML encryption standards, you should use these two derived classes.

For more information on XML encryption standards, see http://www.w3.org/TR/xmlenc-core/.

NoteNote

The HostProtectionAttribute attribute applied to this type or member has the following Resources property value: MayLeakOnAbort. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.

The following code example demonstrates how to encrypt and decrypt an XML element using the EncryptedData class that derives from the EncryptedType class.

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 TripleDES key. 
        TripleDESCryptoServiceProvider tDESkey = new TripleDESCryptoServiceProvider();


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

            // Display the encrypted XML to the console.
            Console.WriteLine("Encrypted XML:");
            Console.WriteLine();
            Console.WriteLine(xmlDoc.OuterXml);

            // Decrypt the "creditcard" element.
            Decrypt(xmlDoc, tDESkey);

            // Display the encrypted XML to the console.
            Console.WriteLine();
            Console.WriteLine("Decrypted XML:");
            Console.WriteLine();
            Console.WriteLine(xmlDoc.OuterXml);
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }
        finally
        {
            // Clear the TripleDES key.
            tDESkey.Clear();
        }

    }

    public static void Encrypt(XmlDocument Doc, string ElementToEncrypt, TripleDESCryptoServiceProvider 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  
        // symmetric key. 
        //////////////////////////////////////////////////

        EncryptedXml eXml = new EncryptedXml();

        byte[] encryptedElement = eXml.EncryptData(elementToEncrypt, Alg, 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. 
        // Determine what kind of algorithm is being used and 
        // supply the appropriate URL to the EncryptionMethod element.

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

        // 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, SymmetricAlgorithm Alg)
    {

        // Find the EncryptedData element in the XmlDocument.
        XmlElement encryptedElement = Doc.GetElementsByTagName("EncryptedData")[0] as XmlElement;

        // If the EncryptedData element was not found, throw an exception. 
        if (encryptedElement == null)
        {
            throw new XmlException("The EncryptedData element was not found.");
        }

        // Create an EncryptedData object and populate it.
        EncryptedData edElement = new EncryptedData();
        edElement.LoadXml(encryptedElement);

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

        // Decrypt the element using the symmetric key. 
        byte[] rgbOutput = exml.DecryptData(edElement, Alg);

        // Replace the encryptedData element with the plaintext XML element.
        exml.ReplaceData(encryptedElement, rgbOutput);

    }


}

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0

.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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