Reference Klasse

Definition

Stellt das <reference>-Element einer XML-Signatur dar.

public ref class Reference
public class Reference
type Reference = class
Public Class Reference
Vererbung
Reference

Beispiele

Im folgenden Codebeispiel wird veranschaulicht, wie eine umhüllte XML-Signatur mithilfe des Reference -Objekts generiert und überprüft wird.

//
// This example signs an XML file using an
// envelope signature. It then verifies the 
// signed XML.
//
#using <System.Security.dll>
#using <System.Xml.dll>

using namespace System;
using namespace System::Security::Cryptography;
using namespace System::Security::Cryptography::X509Certificates;
using namespace System::Security::Cryptography::Xml;
using namespace System::Text;
using namespace System::Xml;

// Sign an XML file and save the signature in a new file.
void SignXmlFile( String^ FileName, String^ SignedFileName, RSA^ Key )
{
   
   // Create a new XML document.
   XmlDocument^ doc = gcnew XmlDocument;
   
   // Format the document to ignore white spaces.
   doc->PreserveWhitespace = false;
   
   // Load the passed XML file using its name.
   doc->Load( gcnew XmlTextReader( FileName ) );
   
   // Create a SignedXml object.
   SignedXml^ signedXml = gcnew SignedXml( doc );
   
   // Add the key to the SignedXml document. 
   signedXml->SigningKey = Key;
   
   // Create a reference to be signed.
   Reference^ reference = gcnew Reference;
   reference->Uri = "";
   
   // Add an enveloped transformation to the reference.
   XmlDsigEnvelopedSignatureTransform^ env = gcnew XmlDsigEnvelopedSignatureTransform;
   reference->AddTransform( env );
   
   // Add the reference to the SignedXml object.
   signedXml->AddReference( reference );
   
   // Add an RSAKeyValue KeyInfo (optional; helps recipient find key to validate).
   KeyInfo^ keyInfo = gcnew KeyInfo;
   keyInfo->AddClause( gcnew RSAKeyValue( safe_cast<RSA^>(Key) ) );
   signedXml->KeyInfo = keyInfo;
   
   // Compute the signature.
   signedXml->ComputeSignature();
   
   // Get the XML representation of the signature and save
   // it to an XmlElement object.
   XmlElement^ xmlDigitalSignature = signedXml->GetXml();
   
   // Append the element to the XML document.
   doc->DocumentElement->AppendChild( doc->ImportNode( xmlDigitalSignature, true ) );
   if ( (doc->FirstChild)->GetType() == XmlDeclaration::typeid )
   {
      doc->RemoveChild( doc->FirstChild );
   }

   
   // Save the signed XML document to a file specified
   // using the passed string.
   XmlTextWriter^ xmltw = gcnew XmlTextWriter( SignedFileName,gcnew UTF8Encoding( false ) );
   doc->WriteTo( xmltw );
   xmltw->Close();
}


// Verify the signature of an XML file and return the result.
Boolean VerifyXmlFile( String^ Name )
{
   
   // Create a new XML document.
   XmlDocument^ xmlDocument = gcnew XmlDocument;
   
   // Format using white spaces.
   xmlDocument->PreserveWhitespace = true;
   
   // Load the passed XML file into the document. 
   xmlDocument->Load( Name );
   
   // Create a new SignedXml object and pass it
   // the XML document class.
   SignedXml^ signedXml = gcnew SignedXml( xmlDocument );
   
   // Find the "Signature" node and create a new
   // XmlNodeList object.
   XmlNodeList^ nodeList = xmlDocument->GetElementsByTagName( "Signature" );
   
   // Load the signature node.
   signedXml->LoadXml( safe_cast<XmlElement^>(nodeList->Item( 0 )) );
   
   // Check the signature and return the result.
   return signedXml->CheckSignature();
}


// Create example data to sign.
void CreateSomeXml( String^ FileName )
{
   
   // Create a new XmlDocument object.
   XmlDocument^ document = gcnew XmlDocument;
   
   // Create a new XmlNode object.
   XmlNode^ node = document->CreateNode( XmlNodeType::Element, "", "MyElement", "samples" );
   
   // Add some text to the node.
   node->InnerText = "Example text to be signed.";
   
   // Append the node to the document.
   document->AppendChild( node );
   
   // Save the XML document to the file name specified.
   XmlTextWriter^ xmltw = gcnew XmlTextWriter( FileName,gcnew UTF8Encoding( false ) );
   document->WriteTo( xmltw );
   xmltw->Close();
}

int main()
{
   try
   {
      
      // Generate a signing key.
      RSA^ Key = RSA::Create();
      
      // Create an XML file to sign.
      CreateSomeXml( "Example.xml" );
      Console::WriteLine( "New XML file created." );
      
      // Sign the XML that was just created and save it in a 
      // new file.
      SignXmlFile( "Example.xml", "SignedExample.xml", Key );
      Console::WriteLine( "XML file signed." );
      
      // Verify the signature of the signed XML.
      Console::WriteLine( "Verifying signature..." );
      bool result = VerifyXmlFile( "SignedExample.xml" );
      
      // Display the results of the signature verification to
      // the console.
      if ( result )
      {
         Console::WriteLine( "The XML signature is valid." );
      }
      else
      {
         Console::WriteLine( "The XML signature is not valid." );
      }
   }
   catch ( CryptographicException^ e ) 
   {
      Console::WriteLine( e->Message );
   }

}
//
// This example signs an XML file using an
// envelope signature. It then verifies the 
// signed XML.
//
using System;
using System.Security.Cryptography;
using System.Security.Cryptography.X509Certificates;
using System.Security.Cryptography.Xml;
using System.Text;
using System.Xml;

public class SignVerifyEnvelope
{

    public static void Main(String[] args)
    {
        try
        {
            // Generate a signing key.
            RSA Key = RSA.Create();

            // Create an XML file to sign.
            CreateSomeXml("Example.xml");
            Console.WriteLine("New XML file created."); 

            // Sign the XML that was just created and save it in a 
            // new file.
            SignXmlFile("Example.xml", "SignedExample.xml", Key);
            Console.WriteLine("XML file signed."); 

            // Verify the signature of the signed XML.
            Console.WriteLine("Verifying signature...");
            bool result = VerifyXmlFile("SignedExample.xml");

            // Display the results of the signature verification to \
            // the console.
            if(result)
            {
                Console.WriteLine("The XML signature is valid.");
            }
            else
            {
                Console.WriteLine("The XML signature is not valid.");
            }
        }
        catch(CryptographicException e)
        {
            Console.WriteLine(e.Message);
        }
    }

    // Sign an XML file and save the signature in a new file.
    public static void SignXmlFile(string FileName, string SignedFileName, RSA Key)
    {
        // Create a new XML document.
        XmlDocument doc = new XmlDocument();

        // Format the document to ignore white spaces.
        doc.PreserveWhitespace = false;

        // Load the passed XML file using it's name.
        doc.Load(new XmlTextReader(FileName));

        // Create a SignedXml object.
        SignedXml signedXml = new SignedXml(doc);

        // Add the key to the SignedXml document. 
        signedXml.SigningKey = Key;

        // Create a reference to be signed.
        Reference reference = new Reference();
        reference.Uri = "";

        // Add an enveloped transformation to the reference.
        XmlDsigEnvelopedSignatureTransform env = new XmlDsigEnvelopedSignatureTransform();
        reference.AddTransform(env);

        // Add the reference to the SignedXml object.
        signedXml.AddReference(reference);

        // Add an RSAKeyValue KeyInfo (optional; helps recipient find key to validate).
        KeyInfo keyInfo = new KeyInfo();
        keyInfo.AddClause(new RSAKeyValue((RSA)Key));
        signedXml.KeyInfo = keyInfo;

        // Compute the signature.
        signedXml.ComputeSignature();

        // Get the XML representation of the signature and save
        // it to an XmlElement object.
        XmlElement xmlDigitalSignature = signedXml.GetXml();

        // Append the element to the XML document.
        doc.DocumentElement.AppendChild(doc.ImportNode(xmlDigitalSignature, true));

        if (doc.FirstChild is XmlDeclaration)  
        {
            doc.RemoveChild(doc.FirstChild);
        }

        // Save the signed XML document to a file specified
        // using the passed string.
        XmlTextWriter xmltw = new XmlTextWriter(SignedFileName, new UTF8Encoding(false));
        doc.WriteTo(xmltw);
        xmltw.Close();
    }
    // Verify the signature of an XML file and return the result.
    public static Boolean VerifyXmlFile(String Name)
    {
        // Create a new XML document.
        XmlDocument xmlDocument = new XmlDocument();

        // Format using white spaces.
        xmlDocument.PreserveWhitespace = true;

        // Load the passed XML file into the document. 
        xmlDocument.Load(Name);

        // Create a new SignedXml object and pass it
        // the XML document class.
        SignedXml signedXml = new SignedXml(xmlDocument);

        // Find the "Signature" node and create a new
        // XmlNodeList object.
        XmlNodeList nodeList = xmlDocument.GetElementsByTagName("Signature");

        // Load the signature node.
        signedXml.LoadXml((XmlElement)nodeList[0]);

        // Check the signature and return the result.
        return signedXml.CheckSignature();
    }

    // Create example data to sign.
    public static void CreateSomeXml(string FileName)
    {
        // Create a new XmlDocument object.
        XmlDocument document = new XmlDocument();

        // Create a new XmlNode object.
        XmlNode  node = document.CreateNode(XmlNodeType.Element, "", "MyElement", "samples");
        
        // Add some text to the node.
        node.InnerText = "Example text to be signed.";

        // Append the node to the document.
        document.AppendChild(node);

        // Save the XML document to the file name specified.
        XmlTextWriter xmltw = new XmlTextWriter(FileName, new UTF8Encoding(false));
        document.WriteTo(xmltw);
        xmltw.Close();
    }
}
'
' This example signs an XML file using an
' envelope signature. It then verifies the 
' signed XML.
'
Imports System.Security.Cryptography
Imports System.Security.Cryptography.X509Certificates
Imports System.Security.Cryptography.Xml
Imports System.Text
Imports System.Xml



Public Class SignVerifyEnvelope
   
   Overloads Public Shared Sub Main(args() As [String])
      Try
         ' Generate a signing key.
         Dim Key As RSA = RSA.Create()
         
         ' Create an XML file to sign.
         CreateSomeXml("Example.xml")
         Console.WriteLine("New XML file created.")
         
         ' Sign the XML that was just created and save it in a 
         ' new file.
         SignXmlFile("Example.xml", "SignedExample.xml", Key)
         Console.WriteLine("XML file signed.")
         
         ' Verify the signature of the signed XML.
         Console.WriteLine("Verifying signature...")
         Dim result As Boolean = VerifyXmlFile("SignedExample.xml")
         
         ' Display the results of the signature verification to \
         ' the console.
         If result Then
            Console.WriteLine("The XML signature is valid.")
         Else
            Console.WriteLine("The XML signature is not valid.")
         End If
      Catch e As CryptographicException
         Console.WriteLine(e.Message)
      End Try
   End Sub 
   
   
   ' Sign an XML file and save the signature in a new file.
   Public Shared Sub SignXmlFile(FileName As String, SignedFileName As String, Key As RSA)
      ' Create a new XML document.
      Dim doc As New XmlDocument()
      
      ' Format the document to ignore white spaces.
      doc.PreserveWhitespace = False
      
      ' Load the passed XML file using it's name.
      doc.Load(New XmlTextReader(FileName))
      
      ' Create a SignedXml object.
      Dim signedXml As New SignedXml(doc)
      
      ' Add the key to the SignedXml document. 
      signedXml.SigningKey = Key
      
      ' Create a reference to be signed.
      Dim reference As New Reference()
      reference.Uri = ""
      
      ' Add an enveloped transformation to the reference.
      Dim env As New XmlDsigEnvelopedSignatureTransform()
      reference.AddTransform(env)
      
      ' Add the reference to the SignedXml object.
      signedXml.AddReference(reference)
      
      
      ' Add an RSAKeyValue KeyInfo (optional; helps recipient find key to validate).
      Dim keyInfo As New KeyInfo()
      keyInfo.AddClause(New RSAKeyValue(CType(Key, RSA)))
      signedXml.KeyInfo = keyInfo
      
      ' Compute the signature.
      signedXml.ComputeSignature()
      
      ' Get the XML representation of the signature and save
      ' it to an XmlElement object.
      Dim xmlDigitalSignature As XmlElement = signedXml.GetXml()
      
      ' Append the element to the XML document.
      doc.DocumentElement.AppendChild(doc.ImportNode(xmlDigitalSignature, True))
      
      
      If TypeOf doc.FirstChild Is XmlDeclaration Then
         doc.RemoveChild(doc.FirstChild)
      End If
      
      ' Save the signed XML document to a file specified
      ' using the passed string.
      Dim xmltw As New XmlTextWriter(SignedFileName, New UTF8Encoding(False))
      doc.WriteTo(xmltw)
      xmltw.Close()
   End Sub 
   ' Verify the signature of an XML file and return the result.
   Public Shared Function VerifyXmlFile(Name As [String]) As [Boolean]
      ' Create a new XML document.
      Dim xmlDocument As New XmlDocument()
      
      ' Format using white spaces.
      xmlDocument.PreserveWhitespace = True
      
      ' Load the passed XML file into the document. 
      xmlDocument.Load(Name)
      
      ' Create a new SignedXml object and pass it
      ' the XML document class.
      Dim signedXml As New SignedXml(xmlDocument)
      
      ' Find the "Signature" node and create a new
      ' XmlNodeList object.
      Dim nodeList As XmlNodeList = xmlDocument.GetElementsByTagName("Signature")
      
      ' Load the signature node.
      signedXml.LoadXml(CType(nodeList(0), XmlElement))
      
      ' Check the signature and return the result.
      Return signedXml.CheckSignature()
   End Function 
   
   
   ' Create example data to sign.
   Public Shared Sub CreateSomeXml(FileName As String)
      ' Create a new XmlDocument object.
      Dim document As New XmlDocument()
      
      ' Create a new XmlNode object.
      Dim node As XmlNode = document.CreateNode(XmlNodeType.Element, "", "MyElement", "samples")
      
      ' Add some text to the node.
      node.InnerText = "Example text to be signed."
      
      ' Append the node to the document.
      document.AppendChild(node)
      
      ' Save the XML document to the file name specified.
      Dim xmltw As New XmlTextWriter(FileName, New UTF8Encoding(False))
      document.WriteTo(xmltw)
      xmltw.Close()
   End Sub 
End Class

Hinweise

Das Reference -Objekt stellt das <reference> Element einer digitalen XML-Signatur dar, die durch die Spezifikation für die digitale XML-Signatur definiert wird.

Verwenden Sie das Reference -Objekt, um die folgenden Informationen anzugeben:

  • Der Digestalgorithmus, der zum Signieren des Datenobjekts verwendet wird. Dieser Wert ist erforderlich.

  • Der Uniform Resource Identifier (URI) des zu signierenden Datenobjekts. Der URI kann einen Dateipfad oder bestimmte Elemente in einem XML-Dokument angeben. Dieser Wert ist erforderlich.

  • Eine Kette von Transformationen, die vor dem Generieren des Digests angewendet werden sollen. Dieser Wert ist optional.

  • Der Typ des zu signierenden Objekts. Dieser Wert ist optional.

  • Ein eindeutiger Bezeichner, der verwendet wird, um auf das aktuelle <reference> Element zu verweisen. Dieser Wert ist optional.

Weitere Informationen zum <reference> Element finden Sie in der W3C-Spezifikation.

Konstruktoren

Reference()

Initialisiert eine neue Instanz der Reference-Klasse mit Standardeigenschaften.

Reference(Stream)

Initialisiert eine neue Instanz der Reference-Klasse mit einem Hashwert des angegebenen Stream.

Reference(String)

Initialisiert eine neue Instanz der Reference-Klasse mit der angegebenen Uri.

Eigenschaften

DigestMethod

Ruft den URI (Uniform Resource Identifier) der Digest-Methode des aktuellen Reference ab oder legt diesen fest.

DigestValue

Ruft den Digest-Wert des aktuellen Reference ab oder legt diesen fest.

Id

Ruft die ID der aktuellen Reference ab oder legt diese fest.

TransformChain

Ruft die Transformationskette des aktuellen Reference ab.

Type

Ruft den Typ des signierten Objekts ab oder legt diesen fest.

Uri

Ruft den Uri der aktuellen Reference ab oder legt ihn fest.

Methoden

AddTransform(Transform)

Fügt der Liste der Transformationen ein Transform-Objekt hinzu, das vor der Übergabe an den Digest-Algorithmus auf die Daten angewendet werden soll.

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 Reference zurück.

LoadXml(XmlElement)

Lädt einen Reference-Zustand aus einem XML-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)

Gilt für: