EncryptedData Třída

Definice

Obor názvů:

System.Security.Cryptography.Xml

Sestavení:

System.Security.Cryptography.Xml.dll

Balíček:

System.Security.Cryptography.Xml v9.0.0-rc.2.24473.5

Zdroj:

EncryptedData.cs

<EncryptedData> Představuje element v šifrování XML. Tato třída se nemůže dědit.

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

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

type EncryptedData = class
    inherit EncryptedType

Public NotInheritable Class EncryptedData
Inherits EncryptedType

Dědičnost

Object

EncryptedType

EncryptedData

Příklady

Následující příklad ukazuje, jak šifrovat a dešifrovat xml element pomocí EncryptedData třídy. Tento příklad pak zobrazí různé vlastnosti EncryptedData třídy pro konzolu.

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 EncryptedData element from the XMLDocument object.
        XmlElement encryptedData = Doc.GetElementsByTagName("EncryptedData")[0] as XmlElement;

        // Create a new EncryptedData object.
        EncryptedData encData = new EncryptedData();

        // Load the XML from the document to
        // initialize the EncryptedData object.
        encData.LoadXml(encryptedData);

        // Display the properties.
        // Most values are Null by default.

        Console.WriteLine("EncryptedData.CipherData: " + encData.CipherData.GetXml().InnerXml);
        Console.WriteLine("EncryptedData.Encoding: " + encData.Encoding);
        Console.WriteLine("EncryptedData.EncryptionMethod: " + encData.EncryptionMethod.GetXml().InnerXml);
        if (encData.EncryptionProperties.Count >= 1)
        {
            Console.WriteLine("EncryptedData.EncryptionProperties: " + encData.EncryptionProperties[0].GetXml().InnerXml);
        }

        Console.WriteLine("EncryptedData.Id: " + encData.Id);
        Console.WriteLine("EncryptedData.KeyInfo: " + encData.KeyInfo.GetXml().InnerXml);
        Console.WriteLine("EncryptedData.MimeType: " + encData.MimeType);
    }
}

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 EncryptedData element from the XMLDocument object.
        Dim encryptedData As XmlElement = Doc.GetElementsByTagName("EncryptedData")(0)

        ' Create a new EncryptedData object.
        Dim encData As New EncryptedData()

        ' Load the XML from the document to
        ' initialize the EncryptedData object.
        encData.LoadXml(encryptedData)

        ' Display the properties.
        ' Most values are Null by default.


        Console.WriteLine("EncryptedData.CipherData: " + encData.CipherData.GetXml().InnerXml)
        Console.WriteLine("EncryptedData.Encoding: " + encData.Encoding)
        Console.WriteLine("EncryptedData.EncryptionMethod: " + encData.EncryptionMethod.GetXml().InnerXml)
        If encData.EncryptionProperties.Count >= 1 Then
            Console.WriteLine("EncryptedData.EncryptionProperties: " + encData.EncryptionProperties(0).GetXml().InnerXml)
        End If

        Console.WriteLine("EncryptedData.Id: " + encData.Id)
        Console.WriteLine("EncryptedData.KeyInfo: " + encData.KeyInfo.GetXml().InnerXml)
        Console.WriteLine("EncryptedData.MimeType: " + encData.MimeType)

    End Sub
End Module

Poznámky

Tato třída se používá k reprezentaci elementu <EncryptedData> v šifrování XML. Tento prvek je základním prvkem v šifrování XML. Jeho podřízený element <CipherData>, obsahuje šifrovaná data. Element <EncryptedData> nahrazuje šifrovaný element nebo slouží jako nový kořen dokumentu.

Konstruktory

EncryptedData()

Inicializuje novou instanci EncryptedData třídy.

Vlastnosti

CipherData	Získá nebo nastaví CipherData hodnotu pro instanci EncryptedType třídy. (Zděděno od EncryptedType)
Encoding	Získá nebo nastaví Encoding atribut EncryptedType instance v šifrování XML. (Zděděno od EncryptedType)
EncryptionMethod	Získá nebo nastaví <EncryptionMethod> element pro šifrování XML. (Zděděno od EncryptedType)
EncryptionProperties	Získá nebo nastaví <EncryptionProperties> element v šifrování XML. (Zděděno od EncryptedType)
Id	Získá nebo nastaví Id atribut EncryptedType instance v šifrování XML. (Zděděno od EncryptedType)
KeyInfo	Získá ze sad elementu <KeyInfo> v šifrování XML. (Zděděno od EncryptedType)
MimeType	Získá nebo nastaví MimeType atribut EncryptedType instance v šifrování XML. (Zděděno od EncryptedType)
Type	Získá nebo nastaví Type atribut EncryptedType instance v šifrování XML. (Zděděno od EncryptedType)

Metody

AddProperty(EncryptionProperty)	<EncryptionProperty> Přidá podřízený prvek do elementu <EncryptedProperties> v aktuálním EncryptedType objektu v šifrování XML. (Zděděno od EncryptedType)
Equals(Object)	Určí, zda se zadaný objekt rovná aktuálnímu objektu. (Zděděno od Object)
GetHashCode()	Slouží jako výchozí hashovací funkce. (Zděděno od Object)
GetType()	Získá aktuální Type instanci. (Zděděno od Object)
GetXml()	Vrátí reprezentaci XML objektu EncryptedData .
LoadXml(XmlElement)	Načte informace XML do elementu <EncryptedData> v šifrování XML.
MemberwiseClone()	Vytvoří mělkou kopii aktuálního Objectsouboru . (Zděděno od Object)
ToString()	Vrátí řetězec, který představuje aktuální objekt. (Zděděno od Object)