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SignedXml.CheckSignature Methode

Definition

Bestimmt, ob die Signature-Eigenschaft überprüft wird.

Überlädt

CheckSignature()

Bestimmt, ob die Signature-Eigenschaft mithilfe des öffentlichen Schlüssels in der Signatur überprüft wird.

CheckSignature(AsymmetricAlgorithm)

Bestimmt, ob die Signature-Eigenschaft für den angegebenen Schlüssel überprüft wird.

CheckSignature(KeyedHashAlgorithm)

Bestimmt, ob die Signature-Eigenschaft für den angegebenen MAC-Algorithmus (Message Authentication Code) überprüft wird.

CheckSignature(X509Certificate2, Boolean)

Bestimmt, ob die Signature-Eigenschaft für das angegebene X509Certificate2-Objekt überprüft wird und, optional, ob das Zertifikat gültig ist.

CheckSignature()

Quelle:
SignedXml.cs
Quelle:
SignedXml.cs
Quelle:
SignedXml.cs
Quelle:
SignedXml.cs
Quelle:
SignedXml.cs

Bestimmt, ob die Signature-Eigenschaft mithilfe des öffentlichen Schlüssels in der Signatur überprüft wird.

public:
 bool CheckSignature();
public bool CheckSignature ();
member this.CheckSignature : unit -> bool
Public Function CheckSignature () As Boolean

Gibt zurück

true, wenn die Signature-Eigenschaft überprüft wird, andernfalls false.

Ausnahmen

Die SignatureAlgorithm-Eigenschaft des öffentlichen Schlüssels in der Signatur entspricht nicht der SignatureMethod-Eigenschaft.

- oder -

Die Signaturbeschreibung konnte nicht erstellt werden.

– oder –

Der Hashalgorithmus konnte nicht erstellt werden.

Beispiele

Im folgenden Codebeispiel wird gezeigt, wie Sie ein gesamtes XML-Dokument mit einer umhüllten Signatur signieren und überprüfen.

//
// 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. This method does not  
// save the public key within the XML file.  This file cannot be verified unless  
// the verifying code has the key with which it was signed.
void SignXmlFile( String^ FileName, String^ SignedFileName, RSA^ Key )
{
   
   // Create a new XML document.
   XmlDocument^ doc = gcnew XmlDocument;
   
   // 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 );
   
   // 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 against an asymmetric 
// algorithm and return the result.
Boolean VerifyXmlFile( String^ Name, RSA^ Key )
{
   
   // Create a new XML document.
   XmlDocument^ xmlDocument = gcnew XmlDocument;
   
   // 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( Key );
}


// 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", Key );
      
      // 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", Key);

           // 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. This method does not  
    // save the public key within the XML file.  This file cannot be verified unless  
    // the verifying code has the key with which it was signed.
    public static void SignXmlFile(string FileName, string SignedFileName, RSA Key)
    {
        // Create a new XML document.
        XmlDocument doc = new XmlDocument();

        // Load the passed XML file using its 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);

        // 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 against an asymmetric 
    // algorithm and return the result.
    public static Boolean VerifyXmlFile(String Name, RSA Key)
    {
        // Create a new XML document.
        XmlDocument xmlDocument = new XmlDocument();

        // 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(Key);
    }

    // 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", Key)
         
         ' 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. This method does not  
   ' save the public key within the XML file.  This file cannot be verified unless  
   ' the verifying code has the key with which it was signed.
   Public Shared Sub SignXmlFile(FileName As String, SignedFileName As String, Key As RSA)
      ' Create a new XML document.
      Dim doc As New XmlDocument()
      
      ' Load the passed XML file using its 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)
      
      ' 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 against an asymmetric 
   ' algorithm and return the result.
   Public Shared Function VerifyXmlFile(Name As [String], Key As RSA) As [Boolean]
      ' Create a new XML document.
      Dim xmlDocument As New XmlDocument()
      
      ' 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(Key)
   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

Im folgenden Codebeispiel wird gezeigt, wie ein adressierbares URI-Objekt (Uniform Resource Identifier) mithilfe einer getrennten Signatur signiert und überprüft wird.

//
// This example signs a file specified by a URI 
// using a detached signature. It then verifies  
// the signed XML.
//
#using <System.dll>
#using <System.Xml.dll>
#using <System.Security.dll>

using namespace System;
using namespace System::Security::Cryptography;
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. This method does not  
// save the public key within the XML file.  This file cannot be verified unless  
// the verifying code has the key with which it was signed.
void SignDetachedResource( String^ URIString, String^ XmlSigFileName, RSA^ Key )
{
   
   // Create a SignedXml object.
   SignedXml^ signedXml = gcnew SignedXml;
   
   // Assign the key to the SignedXml object.
   signedXml->SigningKey = Key;
   
   // Create a reference to be signed.
   Reference^ reference = gcnew Reference;
   
   // Add the passed URI to the reference object.
   reference->Uri = URIString;
   
   // Add the reference to the SignedXml object.
   signedXml->AddReference( reference );
   
   // Compute the signature.
   signedXml->ComputeSignature();
   
   // Get the XML representation of the signature and save
   // it to an XmlElement object.
   XmlElement^ xmlDigitalSignature = signedXml->GetXml();
   
   // Save the signed XML document to a file specified
   // using the passed string.
   XmlTextWriter^ xmltw = gcnew XmlTextWriter( XmlSigFileName,gcnew UTF8Encoding( false ) );
   xmlDigitalSignature->WriteTo( xmltw );
   xmltw->Close();
}


// Verify the signature of an XML file against an asymmetric 
// algorithm and return the result.
static Boolean VerifyDetachedSignature( String^ XmlSigFileName, RSA^ Key )
{
   
   // Create a new XML document.
   XmlDocument^ xmlDocument = gcnew XmlDocument;
   
   // Load the passedXML file into the document.
   xmlDocument->Load( XmlSigFileName );
   
   // Create a new SignedXml object.
   SignedXml^ signedXml = gcnew SignedXml;
   
   // Find the "Signature" node and create a new
   // XmlNodeList object.
   XmlNodeList^ nodeList = xmlDocument->GetElementsByTagName( "Signature" );
   
   // Load the signature node.
   signedXml->LoadXml( dynamic_cast<XmlElement^>(nodeList[ 0 ]) );
   
   // Check the signature against the passed asymmetric key
   // and return the result.
   return signedXml->CheckSignature( Key );
}

int main()
{
   
   // The URI to sign.
   String^ resourceToSign = "http://www.microsoft.com";
   
   // The name of the file to which to save the XML signature.
   String^ XmlFileName = "xmldsig.xml";
   try
   {
      
      // Generate a signing key.
      RSA^ Key = RSA::Create();
      Console::WriteLine( "Signing: {0}", resourceToSign );
      
      // Sign the detached resourceand save the signature in an XML file.
      SignDetachedResource( resourceToSign, XmlFileName, Key );
      Console::WriteLine( "XML Signature was successfully computed and saved to {0}.", XmlFileName );
      
      // Verify the signature of the signed XML.
      Console::WriteLine( "Verifying signature..." );
      
      //Verify the XML signature in the XML file against the key.
      bool result = VerifyDetachedSignature( XmlFileName, Key );
      
      // 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 a file specified by a URI 
// using a detached signature. It then verifies  
// the signed XML.
//

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

class XMLDSIGDetached
{
    
    [STAThread]
    static void Main(string[] args)
    {
        // The URI to sign.
        string resourceToSign = "http://www.microsoft.com";
        
        // The name of the file to which to save the XML signature.
        string XmlFileName = "xmldsig.xml";

        try
        {

            // Generate a signing key.
            RSA Key = RSA.Create();

            Console.WriteLine("Signing: {0}", resourceToSign);

            // Sign the detached resourceand save the signature in an XML file.
            SignDetachedResource(resourceToSign, XmlFileName, Key);

            Console.WriteLine("XML Signature was successfully computed and saved to {0}.", XmlFileName);

            // Verify the signature of the signed XML.
            Console.WriteLine("Verifying signature...");

            //Verify the XML signature in the XML file against the key.
            bool result = VerifyDetachedSignature(XmlFileName, Key);

            // 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. This method does not  
    // save the public key within the XML file.  This file cannot be verified unless  
    // the verifying code has the key with which it was signed.
    public static void SignDetachedResource(string URIString, string XmlSigFileName, RSA Key)
    {
        // Create a SignedXml object.
        SignedXml signedXml = new SignedXml();

        // Assign the key to the SignedXml object.
        signedXml.SigningKey = Key;

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

        // Add the passed URI to the reference object.
        reference.Uri = URIString;
        
        // Add the reference to the SignedXml object.
        signedXml.AddReference(reference);

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

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

        // Save the signed XML document to a file specified
        // using the passed string.
        XmlTextWriter xmltw = new XmlTextWriter(XmlSigFileName, new UTF8Encoding(false));
        xmlDigitalSignature.WriteTo(xmltw);
        xmltw.Close();
    }

    // Verify the signature of an XML file against an asymmetric 
    // algorithm and return the result.
    public static Boolean VerifyDetachedSignature(string XmlSigFileName, RSA Key)
    {	
        // Create a new XML document.
        XmlDocument xmlDocument = new XmlDocument();

        // Load the passedXML file into the document.
        xmlDocument.Load(XmlSigFileName);
    
        // Create a new SignedXml object.
        SignedXml signedXml = new SignedXml();

        // 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 against the passed asymmetric key
        // and return the result.
        return signedXml.CheckSignature(Key);
    }
}
'
' This example signs a file specified by a URI 
' using a detached signature. It then verifies  
' the signed XML.
'
Imports System.Security.Cryptography
Imports System.Security.Cryptography.Xml
Imports System.Text
Imports System.Xml




Class XMLDSIGDetached
   
 
   <STAThread()>  _
   Overloads Shared Sub Main(args() As String)
      ' The URI to sign.
      Dim resourceToSign As String = "http://www.microsoft.com"
      
      ' The name of the file to which to save the XML signature.
      Dim XmlFileName As String = "xmldsig.xml"
      
      Try
         
         ' Generate a signing key.
         Dim Key As RSA = RSA.Create()
         
         Console.WriteLine("Signing: {0}", resourceToSign)
         
         ' Sign the detached resourceand save the signature in an XML file.
         SignDetachedResource(resourceToSign, XmlFileName, Key)
         
         Console.WriteLine("XML Signature was successfully computed and saved to {0}.", XmlFileName)
         
         ' Verify the signature of the signed XML.
         Console.WriteLine("Verifying signature...")
         
         'Verify the XML signature in the XML file against the key.
         Dim result As Boolean = VerifyDetachedSignature(XmlFileName, Key)
         
         ' 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. This method does not  
   ' save the public key within the XML file.  This file cannot be verified unless  
   ' the verifying code has the key with which it was signed.
   Public Shared Sub SignDetachedResource(URIString As String, XmlSigFileName As String, Key As RSA)
      ' Create a SignedXml object.
      Dim signedXml As New SignedXml()
      
      ' Assign the key to the SignedXml object.
      signedXml.SigningKey = Key
      
      ' Create a reference to be signed.
      Dim reference As New Reference()
      
      ' Add the passed URI to the reference object.
      reference.Uri = URIString
      
      ' Add the reference to the SignedXml object.
      signedXml.AddReference(reference)
      
      ' 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()
      
      ' Save the signed XML document to a file specified
      ' using the passed string.
      Dim xmltw As New XmlTextWriter(XmlSigFileName, New UTF8Encoding(False))
      xmlDigitalSignature.WriteTo(xmltw)
      xmltw.Close()
   End Sub 
    
   
   ' Verify the signature of an XML file against an asymmetric 
   ' algorithm and return the result.
   Public Shared Function VerifyDetachedSignature(XmlSigFileName As String, Key As RSA) As [Boolean]
      ' Create a new XML document.
      Dim xmlDocument As New XmlDocument()
      
      ' Load the passedXML file into the document.
      xmlDocument.Load(XmlSigFileName)
      
      ' Create a new SignedXml object.
      Dim signedXml As New SignedXml()
      
      ' 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 against the passed asymmetric key
      ' and return the result.
      Return signedXml.CheckSignature(Key)
   End Function 
End Class

Im folgenden Codebeispiel wird gezeigt, wie sie ein einzelnes Element eines XML-Dokuments mithilfe einer umhüllenden Signatur signieren und überprüfen.

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

using namespace System;
using namespace System::Security::Cryptography;
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.
static void SignXmlFile( String^ FileName, String^ SignedFileName, RSA^ Key, array<String^>^ElementsToSign )
{
   
   // Check the arguments.  
   if ( FileName == nullptr )
      throw gcnew ArgumentNullException( L"FileName" );

   if ( SignedFileName == nullptr )
      throw gcnew ArgumentNullException( L"SignedFileName" );

   if ( Key == nullptr )
      throw gcnew ArgumentNullException( L"Key" );

   if ( ElementsToSign == nullptr )
      throw gcnew ArgumentNullException( L"ElementsToSign" );

   
   // 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 it's 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;
   
   // Loop through each passed element to sign 
   // and create a reference.
   System::Collections::IEnumerator^ myEnum = ElementsToSign->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      String^ s = safe_cast<String^>(myEnum->Current);
      
      // Create a reference to be signed.
      Reference^ reference = gcnew Reference;
      reference->Uri = s;
      
      // 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( dynamic_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 ( dynamic_cast<XmlDeclaration^>(doc->FirstChild) )
   {
      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.
static Boolean VerifyXmlFile( String^ Name )
{
   
   // Check the arguments.  
   if ( Name == nullptr )
      throw gcnew ArgumentNullException( L"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( L"Signature" );
   
   // Load the signature node.
   signedXml->LoadXml( dynamic_cast<XmlElement^>(nodeList->Item( 0 )) );
   
   // Check the signature and return the result.
   return signedXml->CheckSignature();
}

int main()
{
   
   // Generate a signing key.
   RSA^ Key = RSA::Create();
   try
   {
      
      // Specify an element to sign. 
      array<String^>^elements = {L"#tag1"};
      
      // Sign an XML file and save the signature to a 
      // new file.
      SignXmlFile( L"Test.xml", L"SignedExample.xml", Key, elements );
      Console::WriteLine( L"XML file signed." );
      
      // Verify the signature of the signed XML.
      Console::WriteLine( L"Verifying signature..." );
      bool result = VerifyXmlFile( L"SignedExample.xml" );
      
      // Display the results of the signature verification to 
      // the console.
      if ( result )
      {
         Console::WriteLine( L"The XML signature is valid." );
      }
      else
      {
         Console::WriteLine( L"The XML signature is not valid." );
      }
   }
   catch ( CryptographicException^ e ) 
   {
      Console::WriteLine( e->Message );
   }
   finally
   {
      
      // Clear resources associated with the 
      // RSA instance.
      Key->Clear();
   }

   return 1;
}
//
// 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.Xml;
using System.Text;
using System.Xml;

public class SignVerifyEnvelope
{

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

       try
       {
           // Specify an element to sign.
           string[] elements =  { "#tag1" };

           // Sign an XML file and save the signature to a
           // new file.
           SignXmlFile("Test.xml", "SignedExample.xml", Key, elements);
           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);
       }
       finally
       {
           // Clear resources associated with the
           // RSA instance.
           Key.Clear();
       }
   }

    // Sign an XML file and save the signature in a new file.
    public static void SignXmlFile(string FileName, string SignedFileName, RSA Key, string[] ElementsToSign)
    {
        // Check the arguments.
        if (FileName == null)
            throw new ArgumentNullException("FileName");
        if (SignedFileName == null)
            throw new ArgumentNullException("SignedFileName");
        if (Key == null)
            throw new ArgumentNullException("Key");
        if (ElementsToSign == null)
            throw new ArgumentNullException("ElementsToSign");

        // 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;

        // Loop through each passed element to sign
        // and create a reference.
        foreach (string s in ElementsToSign)
        {
            // Create a reference to be signed.
            Reference reference = new Reference();
            reference.Uri = s;

            // 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)
    {
        // Check the arguments.
        if (Name == null)
            throw new ArgumentNullException("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();
    }
}
' This example signs an XML file using an
' envelope signature. It then verifies the 
' signed XML.
'
Imports System.Security.Cryptography
Imports System.Security.Cryptography.Xml
Imports System.Text
Imports System.Xml



Module SignVerifyEnvelope



    Sub Main(ByVal args() As String)
        ' Generate a signing key.
        Dim Key As RSA = RSA.Create()

        Try
            ' Specify an element to sign. 
            Dim elements As String() = New String() {"#tag1"}

            ' Sign an XML file and save the signature to a 
            ' new file.
            SignXmlFile("Test.xml", "SignedExample.xml", Key, elements)
            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)
        Finally
            ' Clear resources associated with the 
            ' RSA instance.
            Key.Clear()
        End Try

    End Sub


    ' Sign an XML file and save the signature in a new file.
    Sub SignXmlFile(ByVal FileName As String, ByVal SignedFileName As String, ByVal Key As RSA, ByVal ElementsToSign() As String)
        ' Check the arguments.  
        If FileName Is Nothing Then
            Throw New ArgumentNullException("FileName")
        End If
        If SignedFileName Is Nothing Then
            Throw New ArgumentNullException("SignedFileName")
        End If
        If Key Is Nothing Then
            Throw New ArgumentNullException("Key")
        End If
        If ElementsToSign Is Nothing Then
            Throw New ArgumentNullException("ElementsToSign")
        End If
        ' 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

        ' Loop through each passed element to sign 
        ' and create a reference.
        Dim s As String
        For Each s In ElementsToSign
            ' Create a reference to be signed.
            Dim reference As New Reference()
            reference.Uri = s

            ' 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)
        Next s

        ' 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.
    Function VerifyXmlFile(ByVal Name As String) As [Boolean]
        ' Check the arguments.  
        If Name Is Nothing Then
            Throw New ArgumentNullException("Name")
        End If
        ' 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
End Module

Hinweise

Diese Methode berechnet auch den Digest der Verweise und den Wert der Signatur.

Wenn ein XML-Dokument mit einer X.509-Signatur signiert wurde, durchsucht die CheckSignature Methode den Speicher "AddressBook" nach Zertifikaten, die für die Überprüfung geeignet sind. Wenn beispielsweise ein Subject Key Identifier (SKI) auf das Zertifikat verweist, wählt die CheckSignature Methode Zertifikate mit diesem SKI aus und probiert sie nacheinander aus, bis das Zertifikat überprüft werden kann.

Gilt für:

CheckSignature(AsymmetricAlgorithm)

Quelle:
SignedXml.cs
Quelle:
SignedXml.cs
Quelle:
SignedXml.cs
Quelle:
SignedXml.cs
Quelle:
SignedXml.cs

Bestimmt, ob die Signature-Eigenschaft für den angegebenen Schlüssel überprüft wird.

public:
 bool CheckSignature(System::Security::Cryptography::AsymmetricAlgorithm ^ key);
public bool CheckSignature (System.Security.Cryptography.AsymmetricAlgorithm key);
member this.CheckSignature : System.Security.Cryptography.AsymmetricAlgorithm -> bool
Public Function CheckSignature (key As AsymmetricAlgorithm) As Boolean

Parameter

key
AsymmetricAlgorithm

Die Implementierung der AsymmetricAlgorithm-Eigenschaft, die den für das Überprüfen der Signature-Eigenschaft verwendeten Schlüssel enthält.

Gibt zurück

true, wenn die Signature-Eigenschaft für den angegebenen Schlüssel überprüft wird; andernfalls false.

Ausnahmen

Der key-Parameter ist null.

Die SignatureAlgorithm-Eigenschaft des key-Parameters entspricht nicht der SignatureMethod-Eigenschaft.

- oder -

Die Signaturbeschreibung konnte nicht erstellt werden.

– oder –

Der Hashalgorithmus konnte nicht erstellt werden.

Beispiele

Im folgenden Codebeispiel wird gezeigt, wie ein adressierbares URI-Objekt (Uniform Resource Identifier) mithilfe einer getrennten Signatur signiert und überprüft wird.

//
// This example signs a file specified by a URI 
// using a detached signature. It then verifies  
// the signed XML.
//
#using <System.dll>
#using <System.Xml.dll>
#using <System.Security.dll>

using namespace System;
using namespace System::Security::Cryptography;
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. This method does not  
// save the public key within the XML file.  This file cannot be verified unless  
// the verifying code has the key with which it was signed.
void SignDetachedResource( String^ URIString, String^ XmlSigFileName, RSA^ Key )
{
   
   // Create a SignedXml object.
   SignedXml^ signedXml = gcnew SignedXml;
   
   // Assign the key to the SignedXml object.
   signedXml->SigningKey = Key;
   
   // Create a reference to be signed.
   Reference^ reference = gcnew Reference;
   
   // Add the passed URI to the reference object.
   reference->Uri = URIString;
   
   // Add the reference to the SignedXml object.
   signedXml->AddReference( reference );
   
   // Compute the signature.
   signedXml->ComputeSignature();
   
   // Get the XML representation of the signature and save
   // it to an XmlElement object.
   XmlElement^ xmlDigitalSignature = signedXml->GetXml();
   
   // Save the signed XML document to a file specified
   // using the passed string.
   XmlTextWriter^ xmltw = gcnew XmlTextWriter( XmlSigFileName,gcnew UTF8Encoding( false ) );
   xmlDigitalSignature->WriteTo( xmltw );
   xmltw->Close();
}


// Verify the signature of an XML file against an asymmetric 
// algorithm and return the result.
static Boolean VerifyDetachedSignature( String^ XmlSigFileName, RSA^ Key )
{
   
   // Create a new XML document.
   XmlDocument^ xmlDocument = gcnew XmlDocument;
   
   // Load the passedXML file into the document.
   xmlDocument->Load( XmlSigFileName );
   
   // Create a new SignedXml object.
   SignedXml^ signedXml = gcnew SignedXml;
   
   // Find the "Signature" node and create a new
   // XmlNodeList object.
   XmlNodeList^ nodeList = xmlDocument->GetElementsByTagName( "Signature" );
   
   // Load the signature node.
   signedXml->LoadXml( dynamic_cast<XmlElement^>(nodeList[ 0 ]) );
   
   // Check the signature against the passed asymmetric key
   // and return the result.
   return signedXml->CheckSignature( Key );
}

int main()
{
   
   // The URI to sign.
   String^ resourceToSign = "http://www.microsoft.com";
   
   // The name of the file to which to save the XML signature.
   String^ XmlFileName = "xmldsig.xml";
   try
   {
      
      // Generate a signing key.
      RSA^ Key = RSA::Create();
      Console::WriteLine( "Signing: {0}", resourceToSign );
      
      // Sign the detached resourceand save the signature in an XML file.
      SignDetachedResource( resourceToSign, XmlFileName, Key );
      Console::WriteLine( "XML Signature was successfully computed and saved to {0}.", XmlFileName );
      
      // Verify the signature of the signed XML.
      Console::WriteLine( "Verifying signature..." );
      
      //Verify the XML signature in the XML file against the key.
      bool result = VerifyDetachedSignature( XmlFileName, Key );
      
      // 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 a file specified by a URI 
// using a detached signature. It then verifies  
// the signed XML.
//

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

class XMLDSIGDetached
{
    
    [STAThread]
    static void Main(string[] args)
    {
        // The URI to sign.
        string resourceToSign = "http://www.microsoft.com";
        
        // The name of the file to which to save the XML signature.
        string XmlFileName = "xmldsig.xml";

        try
        {

            // Generate a signing key.
            RSA Key = RSA.Create();

            Console.WriteLine("Signing: {0}", resourceToSign);

            // Sign the detached resourceand save the signature in an XML file.
            SignDetachedResource(resourceToSign, XmlFileName, Key);

            Console.WriteLine("XML Signature was successfully computed and saved to {0}.", XmlFileName);

            // Verify the signature of the signed XML.
            Console.WriteLine("Verifying signature...");

            //Verify the XML signature in the XML file against the key.
            bool result = VerifyDetachedSignature(XmlFileName, Key);

            // 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. This method does not  
    // save the public key within the XML file.  This file cannot be verified unless  
    // the verifying code has the key with which it was signed.
    public static void SignDetachedResource(string URIString, string XmlSigFileName, RSA Key)
    {
        // Create a SignedXml object.
        SignedXml signedXml = new SignedXml();

        // Assign the key to the SignedXml object.
        signedXml.SigningKey = Key;

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

        // Add the passed URI to the reference object.
        reference.Uri = URIString;
        
        // Add the reference to the SignedXml object.
        signedXml.AddReference(reference);

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

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

        // Save the signed XML document to a file specified
        // using the passed string.
        XmlTextWriter xmltw = new XmlTextWriter(XmlSigFileName, new UTF8Encoding(false));
        xmlDigitalSignature.WriteTo(xmltw);
        xmltw.Close();
    }

    // Verify the signature of an XML file against an asymmetric 
    // algorithm and return the result.
    public static Boolean VerifyDetachedSignature(string XmlSigFileName, RSA Key)
    {	
        // Create a new XML document.
        XmlDocument xmlDocument = new XmlDocument();

        // Load the passedXML file into the document.
        xmlDocument.Load(XmlSigFileName);
    
        // Create a new SignedXml object.
        SignedXml signedXml = new SignedXml();

        // 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 against the passed asymmetric key
        // and return the result.
        return signedXml.CheckSignature(Key);
    }
}
'
' This example signs a file specified by a URI 
' using a detached signature. It then verifies  
' the signed XML.
'
Imports System.Security.Cryptography
Imports System.Security.Cryptography.Xml
Imports System.Text
Imports System.Xml




Class XMLDSIGDetached
   
 
   <STAThread()>  _
   Overloads Shared Sub Main(args() As String)
      ' The URI to sign.
      Dim resourceToSign As String = "http://www.microsoft.com"
      
      ' The name of the file to which to save the XML signature.
      Dim XmlFileName As String = "xmldsig.xml"
      
      Try
         
         ' Generate a signing key.
         Dim Key As RSA = RSA.Create()
         
         Console.WriteLine("Signing: {0}", resourceToSign)
         
         ' Sign the detached resourceand save the signature in an XML file.
         SignDetachedResource(resourceToSign, XmlFileName, Key)
         
         Console.WriteLine("XML Signature was successfully computed and saved to {0}.", XmlFileName)
         
         ' Verify the signature of the signed XML.
         Console.WriteLine("Verifying signature...")
         
         'Verify the XML signature in the XML file against the key.
         Dim result As Boolean = VerifyDetachedSignature(XmlFileName, Key)
         
         ' 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. This method does not  
   ' save the public key within the XML file.  This file cannot be verified unless  
   ' the verifying code has the key with which it was signed.
   Public Shared Sub SignDetachedResource(URIString As String, XmlSigFileName As String, Key As RSA)
      ' Create a SignedXml object.
      Dim signedXml As New SignedXml()
      
      ' Assign the key to the SignedXml object.
      signedXml.SigningKey = Key
      
      ' Create a reference to be signed.
      Dim reference As New Reference()
      
      ' Add the passed URI to the reference object.
      reference.Uri = URIString
      
      ' Add the reference to the SignedXml object.
      signedXml.AddReference(reference)
      
      ' 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()
      
      ' Save the signed XML document to a file specified
      ' using the passed string.
      Dim xmltw As New XmlTextWriter(XmlSigFileName, New UTF8Encoding(False))
      xmlDigitalSignature.WriteTo(xmltw)
      xmltw.Close()
   End Sub 
    
   
   ' Verify the signature of an XML file against an asymmetric 
   ' algorithm and return the result.
   Public Shared Function VerifyDetachedSignature(XmlSigFileName As String, Key As RSA) As [Boolean]
      ' Create a new XML document.
      Dim xmlDocument As New XmlDocument()
      
      ' Load the passedXML file into the document.
      xmlDocument.Load(XmlSigFileName)
      
      ' Create a new SignedXml object.
      Dim signedXml As New SignedXml()
      
      ' 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 against the passed asymmetric key
      ' and return the result.
      Return signedXml.CheckSignature(Key)
   End Function 
End Class

Im folgenden Codebeispiel wird gezeigt, wie Sie ein gesamtes XML-Dokument mit einer umhüllten Signatur signieren und überprüfen.

//
// 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. This method does not  
// save the public key within the XML file.  This file cannot be verified unless  
// the verifying code has the key with which it was signed.
void SignXmlFile( String^ FileName, String^ SignedFileName, RSA^ Key )
{
   
   // Create a new XML document.
   XmlDocument^ doc = gcnew XmlDocument;
   
   // 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 );
   
   // 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 against an asymmetric 
// algorithm and return the result.
Boolean VerifyXmlFile( String^ Name, RSA^ Key )
{
   
   // Create a new XML document.
   XmlDocument^ xmlDocument = gcnew XmlDocument;
   
   // 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( Key );
}


// 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", Key );
      
      // 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", Key);

           // 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. This method does not  
    // save the public key within the XML file.  This file cannot be verified unless  
    // the verifying code has the key with which it was signed.
    public static void SignXmlFile(string FileName, string SignedFileName, RSA Key)
    {
        // Create a new XML document.
        XmlDocument doc = new XmlDocument();

        // Load the passed XML file using its 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);

        // 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 against an asymmetric 
    // algorithm and return the result.
    public static Boolean VerifyXmlFile(String Name, RSA Key)
    {
        // Create a new XML document.
        XmlDocument xmlDocument = new XmlDocument();

        // 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(Key);
    }

    // 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", Key)
         
         ' 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. This method does not  
   ' save the public key within the XML file.  This file cannot be verified unless  
   ' the verifying code has the key with which it was signed.
   Public Shared Sub SignXmlFile(FileName As String, SignedFileName As String, Key As RSA)
      ' Create a new XML document.
      Dim doc As New XmlDocument()
      
      ' Load the passed XML file using its 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)
      
      ' 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 against an asymmetric 
   ' algorithm and return the result.
   Public Shared Function VerifyXmlFile(Name As [String], Key As RSA) As [Boolean]
      ' Create a new XML document.
      Dim xmlDocument As New XmlDocument()
      
      ' 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(Key)
   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

Gilt für:

CheckSignature(KeyedHashAlgorithm)

Quelle:
SignedXml.cs
Quelle:
SignedXml.cs
Quelle:
SignedXml.cs
Quelle:
SignedXml.cs
Quelle:
SignedXml.cs

Bestimmt, ob die Signature-Eigenschaft für den angegebenen MAC-Algorithmus (Message Authentication Code) überprüft wird.

public:
 bool CheckSignature(System::Security::Cryptography::KeyedHashAlgorithm ^ macAlg);
public bool CheckSignature (System.Security.Cryptography.KeyedHashAlgorithm macAlg);
member this.CheckSignature : System.Security.Cryptography.KeyedHashAlgorithm -> bool
Public Function CheckSignature (macAlg As KeyedHashAlgorithm) As Boolean

Parameter

macAlg
KeyedHashAlgorithm

Die Implementierung der KeyedHashAlgorithm-Klasse, die den für das Überprüfen der Signature-Eigenschaft verwendeten MAC enthält.

Gibt zurück

true, wenn die Signature-Eigenschaft für den angegebenen MAC überprüft wird, andernfalls false.

Ausnahmen

Der macAlg-Parameter ist null.

Die HashSize-Eigenschaft des angegebenen KeyedHashAlgorithm-Objekts ist ungültig.

- oder -

Die Signature-Eigenschaft ist null.

- oder -

Die kryptografische Transformation für das Überprüfen der Signatur konnte nicht erstellt werden.

Beispiele

Im folgenden Codebeispiel wird gezeigt, wie ein adressierbares URI-Objekt (Uniform Resource Identifier) mithilfe einer getrennten Signatur signiert und überprüft wird.

//
// This example signs a file specified by a URI 
// using a detached 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::Xml;
using namespace System::Text;
using namespace System::Xml;

// Sign an XML file and save the signature in a new file.
void SignDetachedResource( String^ URIString, String^ XmlSigFileName, KeyedHashAlgorithm^ Key )
{
   
   // Create a SignedXml object.
   SignedXml^ signedXml = gcnew SignedXml;
   
   // Create a reference to be signed.
   Reference^ reference = gcnew Reference;
   
   // Add the passed URI to the reference object.
   reference->Uri = URIString;
   
   // Add the reference to the SignedXml object.
   signedXml->AddReference( reference );
   
   // Compute the signature.
   signedXml->ComputeSignature( Key );
   
   // Get the XML representation of the signature and save
   // it to an XmlElement object.
   XmlElement^ xmlDigitalSignature = signedXml->GetXml();
   
   // Save the signed XML document to a file specified
   // using the passed string.
   XmlTextWriter^ xmltw = gcnew XmlTextWriter( XmlSigFileName,gcnew UTF8Encoding( false ) );
   xmlDigitalSignature->WriteTo( xmltw );
   xmltw->Close();
}


// Verify the signature of an XML file and return the result.
Boolean VerifyDetachedSignature( String^ XmlSigFileName, KeyedHashAlgorithm^ Key )
{
   
   // Create a new XML document.
   XmlDocument^ xmlDocument = gcnew XmlDocument;
   
   // Load the passedXML file into the document.
   xmlDocument->Load( XmlSigFileName );
   
   // Create a new SignedXml object and pass it
   // the XML document class.
   SignedXml^ signedXml = gcnew SignedXml;
   
   // 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( Key );
}

int main()
{
   try
   {
      
      // The URI to sign.
      String^ resourceToSign = "http://www.microsoft.com";
      
      // The name of the file to which to save the XML signature.
      String^ XmlFileName = "xmlsig.xml";
      
      // Generate a signing key.
      HMACSHA256^ Key = gcnew HMACSHA256;
      Console::WriteLine( "Signing: {0}", resourceToSign );
      
      // Sign the detached resourceand save the signature in an XML file.
      SignDetachedResource( resourceToSign, XmlFileName, Key );
      Console::WriteLine( "XML signature was successfully computed and saved to {0}.", XmlFileName );
      
      // Verify the signature of the signed XML.
      Console::WriteLine( "Verifying signature..." );
      
      //Verify the XML signature in the XML file.
      bool result = VerifyDetachedSignature( XmlFileName, Key );
      
      // 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 a file specified by a URI 
// using a detached signature. It then verifies  
// the signed XML.
//

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

class XMLDSIGDetached
{
    
    [STAThread]
    static void Main(string[] args)
    {
        try
        {
            // The URI to sign.
            string resourceToSign = "http://www.microsoft.com";
        
            // The name of the file to which to save the XML signature.
            string XmlFileName = "xmlsig.xml";

            // Generate a signing key.
            HMACSHA256 Key = new HMACSHA256();

            Console.WriteLine("Signing: {0}", resourceToSign);

            // Sign the detached resourceand save the signature in an XML file.
            SignDetachedResource(resourceToSign, XmlFileName, Key);

            Console.WriteLine("XML signature was successfully computed and saved to {0}.", XmlFileName);

            // Verify the signature of the signed XML.
            Console.WriteLine("Verifying signature...");

            //Verify the XML signature in the XML file.
            bool result = VerifyDetachedSignature(XmlFileName, Key);

            // 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 SignDetachedResource(string URIString, string XmlSigFileName, KeyedHashAlgorithm Key)
    {
        // Create a SignedXml object.
        SignedXml signedXml = new SignedXml();

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

        // Add the passed URI to the reference object.
        reference.Uri = URIString;
        
        // Add the reference to the SignedXml object.
        signedXml.AddReference(reference);

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

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

        // Save the signed XML document to a file specified
        // using the passed string.
        XmlTextWriter xmltw = new XmlTextWriter(XmlSigFileName, new UTF8Encoding(false));
        xmlDigitalSignature.WriteTo(xmltw);
        xmltw.Close();
    }

    // Verify the signature of an XML file and return the result.
    public static Boolean VerifyDetachedSignature(string XmlSigFileName, KeyedHashAlgorithm Key)
    {	
        // Create a new XML document.
        XmlDocument xmlDocument = new XmlDocument();

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

        // 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(Key);
    }
}
'
' This example signs a file specified by a URI 
' using a detached signature. It then verifies  
' the signed XML.
'
Imports System.Security.Cryptography
Imports System.Security.Cryptography.Xml
Imports System.Text
Imports System.Xml


Class XMLDSIGDetached
   
 
   <STAThread()>  _
   Overloads Shared Sub Main(args() As String)
      Try
         ' The URI to sign.
         Dim resourceToSign As String = "http://www.microsoft.com"
         
         ' The name of the file to which to save the XML signature.
         Dim XmlFileName As String = "xmlsig.xml"
         
         ' Generate a signing key.
         Dim Key As New HMACSHA256()
         
         Console.WriteLine("Signing: {0}", resourceToSign)
         
         ' Sign the detached resourceand save the signature in an XML file.
         SignDetachedResource(resourceToSign, XmlFileName, Key)
         
         Console.WriteLine("XML signature was successfully computed and saved to {0}.", XmlFileName)
         
         ' Verify the signature of the signed XML.
         Console.WriteLine("Verifying signature...")
         
         'Verify the XML signature in the XML file.
         Dim result As Boolean = VerifyDetachedSignature(XmlFileName, Key)
         
         ' 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 SignDetachedResource(URIString As String, XmlSigFileName As String, Key As KeyedHashAlgorithm)
      ' Create a SignedXml object.
      Dim signedXml As New SignedXml()
      
      ' Create a reference to be signed.
      Dim reference As New Reference()
      
      ' Add the passed URI to the reference object.
      reference.Uri = URIString
      
      ' Add the reference to the SignedXml object.
      signedXml.AddReference(reference)
      
      ' Compute the signature.
      signedXml.ComputeSignature(Key)
      
      ' Get the XML representation of the signature and save
      ' it to an XmlElement object.
      Dim xmlDigitalSignature As XmlElement = signedXml.GetXml()
      
      ' Save the signed XML document to a file specified
      ' using the passed string.
      Dim xmltw As New XmlTextWriter(XmlSigFileName, New UTF8Encoding(False))
      xmlDigitalSignature.WriteTo(xmltw)
      xmltw.Close()
   End Sub 
    
   
   ' Verify the signature of an XML file and return the result.
   Public Shared Function VerifyDetachedSignature(XmlSigFileName As String, Key As KeyedHashAlgorithm) As [Boolean]
      ' Create a new XML document.
      Dim xmlDocument As New XmlDocument()
      
      ' Load the passedXML file into the document.
      xmlDocument.Load(XmlSigFileName)
      
      ' Create a new SignedXml object and pass it
      ' the XML document class.
      Dim signedXml As New SignedXml()
      
      ' 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(Key)
   End Function 
End Class

Im folgenden Codebeispiel wird gezeigt, wie ein gesamtes XML-Dokument mit einer umhüllenden Signatur signiert 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, KeyedHashAlgorithm^ 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 );
   
   // 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 );
   
   // Compute the signature.
   signedXml->ComputeSignature( Key );
   
   // 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, KeyedHashAlgorithm^ Key )
{
   
   // 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( Key );
}


// 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 filename specified.
   XmlTextWriter^ xmltw = gcnew XmlTextWriter( FileName,gcnew UTF8Encoding( false ) );
   document->WriteTo( xmltw );
   xmltw->Close();
}

int main()
{
   try
   {
      
      // Generate a signing key.
      HMACSHA256^ Key = gcnew HMACSHA256;
      
      // 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", Key );
      
      // 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 );
   }

   return 0;
}
//
// 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.
            HMACSHA256 Key = new HMACSHA256();

            // 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", Key);

            // 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, KeyedHashAlgorithm 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);

        // 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);

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

        // 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, KeyedHashAlgorithm Key)
    {
        // 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(Key);
    }

    // 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 filename 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 New HMACSHA256()
         
         ' 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", Key)
         
         ' 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 KeyedHashAlgorithm)
      ' 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)
      
      ' 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)
      
      ' Compute the signature.
      signedXml.ComputeSignature(Key)
      
      ' 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], Key As KeyedHashAlgorithm) 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(Key)
   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 filename specified.
      Dim xmltw As New XmlTextWriter(FileName, New UTF8Encoding(False))
      document.WriteTo(xmltw)
      xmltw.Close()
   End Sub 
End Class

Gilt für:

CheckSignature(X509Certificate2, Boolean)

Quelle:
SignedXml.cs
Quelle:
SignedXml.cs
Quelle:
SignedXml.cs
Quelle:
SignedXml.cs
Quelle:
SignedXml.cs

Bestimmt, ob die Signature-Eigenschaft für das angegebene X509Certificate2-Objekt überprüft wird und, optional, ob das Zertifikat gültig ist.

public:
 bool CheckSignature(System::Security::Cryptography::X509Certificates::X509Certificate2 ^ certificate, bool verifySignatureOnly);
public bool CheckSignature (System.Security.Cryptography.X509Certificates.X509Certificate2 certificate, bool verifySignatureOnly);
[System.Runtime.InteropServices.ComVisible(false)]
public bool CheckSignature (System.Security.Cryptography.X509Certificates.X509Certificate2 certificate, bool verifySignatureOnly);
member this.CheckSignature : System.Security.Cryptography.X509Certificates.X509Certificate2 * bool -> bool
[<System.Runtime.InteropServices.ComVisible(false)>]
member this.CheckSignature : System.Security.Cryptography.X509Certificates.X509Certificate2 * bool -> bool
Public Function CheckSignature (certificate As X509Certificate2, verifySignatureOnly As Boolean) As Boolean

Parameter

certificate
X509Certificate2

Das X509Certificate2-Objekt für die Überprüfung der Signature-Eigenschaft.

verifySignatureOnly
Boolean

true, für die Überprüfung der Signatur allein; false für die Überprüfung der Signatur und des Zertifikats.

Gibt zurück

true, wenn die Signatur gültig ist, andernfalls false.

- oder -

true, wenn die Signatur und das Zertifikat gültig sind, andernfalls false.

Attribute

Ausnahmen

Der certificate-Parameter ist null.

Für den certificate-Parameter konnte keine Signaturbeschreibung erstellt werden.

Beispiele

Im folgenden Codebeispiel wird ein X.509-Zertifikat aus einem Zertifikatspeicher verwendet, um ein XML-Dokument zu signieren und zu überprüfen.

//
// This example signs an XML file using an
// envelope signature. It then verifies the
// signed XML.
//
// You must have a certificate with a subject name
// of "CN=XMLDSIG_Test" in the "My" certificate store.
//
// Run the following command to create a certificate
// and place it in the store.
// makecert -r -pe -n "CN=XMLDSIG_Test" -b 01/01/2005 -e 01/01/2010 -sky signing -ss my

using System;
using System.Security.Cryptography;
using System.Security.Cryptography.Xml;
using System.Security.Cryptography.X509Certificates;
using System.Text;
using System.Xml;

public class SignVerifyEnvelope
{

    public static void Main(String[] args)
    {

        string Certificate = "CN=XMLDSIG_Test";

        try
        {

            // 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", Certificate);
            Console.WriteLine("XML file signed.");

            if (VerifyXmlFile("SignedExample.xml", Certificate))
            {
                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, string SubjectName)
    {
        if (null == FileName)
            throw new ArgumentNullException("FileName");
        if (null == SignedFileName)
            throw new ArgumentNullException("SignedFileName");
        if (null == SubjectName)
            throw new ArgumentNullException("SubjectName");

        // Load the certificate from the certificate store.
        X509Certificate2 cert = GetCertificateBySubject(SubjectName);

        // 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 = cert.GetRSAPrivateKey();

        // 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);

        // Create a new KeyInfo object.
        KeyInfo keyInfo = new KeyInfo();

        // Load the certificate into a KeyInfoX509Data object
        // and add it to the KeyInfo object.
        keyInfo.AddClause(new KeyInfoX509Data(cert));

        // Add the KeyInfo object to the SignedXml object.
        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.
        using (XmlTextWriter xmltw = new XmlTextWriter(SignedFileName, new UTF8Encoding(false)))
        {
            doc.WriteTo(xmltw);
            xmltw.Close();
        }
    }

    // Verify the signature of an XML file against an asymmetric
    // algorithm and return the result.
    public static Boolean VerifyXmlFile(String FileName, String CertificateSubject)
    {
        // Check the args.
        if (null == FileName)
            throw new ArgumentNullException("FileName");
        if (null == CertificateSubject)
            throw new ArgumentNullException("CertificateSubject");

        // Load the certificate from the store.
        X509Certificate2 cert = GetCertificateBySubject(CertificateSubject);

        // Create a new XML document.
        XmlDocument xmlDocument = new XmlDocument();

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

        // 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(cert, true);
    }

    public static X509Certificate2 GetCertificateBySubject(string CertificateSubject)
    {
        // Check the args.
        if (null == CertificateSubject)
            throw new ArgumentNullException("CertificateSubject");

        // Load the certificate from the certificate store.
        X509Certificate2 cert = null;

        X509Store store = new X509Store("My", StoreLocation.CurrentUser);

        try
        {
            // Open the store.
            store.Open(OpenFlags.ReadOnly | OpenFlags.OpenExistingOnly);

            // Get the certs from the store.
            X509Certificate2Collection CertCol = store.Certificates;

            // Find the certificate with the specified subject.
            foreach (X509Certificate2 c in CertCol)
            {
                if (c.Subject == CertificateSubject)
                {
                    cert = c;
                    break;
                }
            }

            // Throw an exception of the certificate was not found.
            if (cert == null)
            {
                throw new CryptographicException("The certificate could not be found.");
            }
        }
        finally
        {
            // Close the store even if an exception was thrown.
            store.Close();
        }

        return cert;
    }

    // Create example data to sign.
    public static void CreateSomeXml(string FileName)
    {
        // Check the args.
        if (null == FileName)
            throw new ArgumentNullException("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.
        using (XmlTextWriter xmltw = new XmlTextWriter(FileName, new UTF8Encoding(false)))
        {
            document.WriteTo(xmltw);

            xmltw.Close();
        }
    }
}
// This code example displays the following to the console:
//
// New XML file created.
// XML file signed.
// The XML signature is valid.
'
' This example signs an XML file using an
' envelope signature. It then verifies the 
' signed XML.
'
' You must have a certificate with a subject name
' of "CN=XMLDSIG_Test" in the "My" certificate store. 
'
' Run the following command to create a certificate
' and place it in the store.
' makecert -r -pe -n "CN=XMLDSIG_Test" -b 01/01/2005 -e 01/01/2010 -sky signing -ss my
Imports System.Security.Cryptography
Imports System.Security.Cryptography.Xml
Imports System.Security.Cryptography.X509Certificates
Imports System.Text
Imports System.Xml



Module SignVerifyEnvelope


    Sub Main(ByVal args() As String)

        Dim Certificate As String = "CN=XMLDSIG_Test"

        Try

            ' 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", Certificate)
            Console.WriteLine("XML file signed.")

            If VerifyXmlFile("SignedExample.xml", Certificate) 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.
    Sub SignXmlFile(ByVal FileName As String, ByVal SignedFileName As String, ByVal SubjectName As String)
        If Nothing = FileName Then
            Throw New ArgumentNullException("FileName")
        End If
        If Nothing = SignedFileName Then
            Throw New ArgumentNullException("SignedFileName")
        End If
        If Nothing = SubjectName Then
            Throw New ArgumentNullException("SubjectName")
        End If
        ' Load the certificate from the certificate store.
        Dim cert As X509Certificate2 = GetCertificateBySubject(SubjectName)

        ' 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 = cert.GetRSAPrivateKey()

        ' 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)

        ' Create a new KeyInfo object.
        Dim keyInfo As New KeyInfo()

        ' Load the certificate into a KeyInfoX509Data object
        ' and add it to the KeyInfo object.
        keyInfo.AddClause(New KeyInfoX509Data(cert))

        ' Add the KeyInfo object to the SignedXml object.
        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))
        Try
            doc.WriteTo(xmltw)

        Finally
            xmltw.Close()
        End Try

    End Sub

    ' Verify the signature of an XML file against an asymmetric 
    ' algorithm and return the result.
    Function VerifyXmlFile(ByVal FileName As String, ByVal CertificateSubject As String) As [Boolean]
        ' Check the args.
        If Nothing = FileName Then
            Throw New ArgumentNullException("FileName")
        End If
        If Nothing = CertificateSubject Then
            Throw New ArgumentNullException("CertificateSubject")
        End If
        ' Load the certificate from the store.
        Dim cert As X509Certificate2 = GetCertificateBySubject(CertificateSubject)

        ' Create a new XML document.
        Dim xmlDocument As New XmlDocument()

        ' Load the passed XML file into the document. 
        xmlDocument.Load(FileName)

        ' 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(cert, True)

    End Function



    Function GetCertificateBySubject(ByVal CertificateSubject As String) As X509Certificate2
        ' Check the args.
        If Nothing = CertificateSubject Then
            Throw New ArgumentNullException("CertificateSubject")
        End If

        ' Load the certificate from the certificate store.
        Dim cert As X509Certificate2 = Nothing

        Dim store As New X509Store("My", StoreLocation.CurrentUser)

        Try
            ' Open the store.
            store.Open(OpenFlags.ReadOnly Or OpenFlags.OpenExistingOnly)

            ' Get the certs from the store.
            Dim CertCol As X509Certificate2Collection = store.Certificates

            ' Find the certificate with the specified subject.
            Dim c As X509Certificate2
            For Each c In CertCol
                If c.Subject = CertificateSubject Then
                    cert = c
                    Exit For
                End If
            Next c

            ' Throw an exception of the certificate was not found.
            If cert Is Nothing Then
                Throw New CryptographicException("The certificate could not be found.")
            End If
        Finally
            ' Close the store even if an exception was thrown.
            store.Close()
        End Try

        Return cert

    End Function


    ' Create example data to sign.
    Sub CreateSomeXml(ByVal FileName As String)
        ' Check the args.
        If Nothing = FileName Then
            Throw New ArgumentNullException("FileName")
        End If
        ' 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))
        Try
            document.WriteTo(xmltw)

        Finally
            xmltw.Close()
        End Try

    End Sub
End Module
' This code example displays the following to the console:
'
' New XML file created.
' XML file signed.
' The XML signature is valid.

Hinweise

In Version 1.1 des .NET Framework wird das X.509-Zertifikat nicht überprüft. In Version 2.0 und höher wird das X.509-Zertifikat überprüft.

In Version 2.0 und höher des .NET Framework durchsucht die CheckSignature Methode den Speicher "AddressBook" nach Zertifikaten, die für die Überprüfung geeignet sind. Wenn beispielsweise ein Subject Key Identifier (SKI) auf das Zertifikat verweist, wählt die CheckSignature Methode Zertifikate mit diesem SKI aus und probiert sie nacheinander aus, bis das Zertifikat überprüft werden kann.

Gilt für: