XmlDsigExcC14NTransform Classe

Definição

Namespace:

System.Security.Cryptography.Xml

Assembly:

System.Security.Cryptography.Xml.dll

Pacote:

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

Origem:

XmlDsigExcC14NTransform.cs

Representa a transformação de canonização C14N XML exclusiva para uma assinatura digital, conforme definido pelo W3C (World Wide Web Consortium), sem comentários.

public ref class XmlDsigExcC14NTransform : System::Security::Cryptography::Xml::Transform

public class XmlDsigExcC14NTransform : System.Security.Cryptography.Xml.Transform

type XmlDsigExcC14NTransform = class
    inherit Transform

Public Class XmlDsigExcC14NTransform
Inherits Transform

Herança

Object

Transform

XmlDsigExcC14NTransform

Derivado

System.Security.Cryptography.Xml.XmlDsigExcC14NWithCommentsTransform

Exemplos

O exemplo de código a seguir mostra como assinar um documento XML com a classe XmlDsigExcC14NTransform usando uma assinatura de envelope.

//
// 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::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.
static void SignXmlFile( String^ FileName, String^ SignedFileName, RSA^ Key )
{
   
   // Create a new XML document.
   XmlDocument^ doc = gcnew XmlDocument;
   
   // Format the document to ignore white spaces.
   doc->PreserveWhitespace = false;
   
   // Load the passed XML file using 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;
   
   // Specify a canonicalization method.
   signedXml->SignedInfo->CanonicalizationMethod = SignedXml::XmlDsigExcC14NTransformUrl;
   
   // Set the InclusiveNamespacesPrefixList property.        
   XmlDsigExcC14NTransform^ canMethod = dynamic_cast<XmlDsigExcC14NTransform^>(signedXml->SignedInfo->CanonicalizationMethodObject);
   canMethod->InclusiveNamespacesPrefixList = L"Sign";
   
   // Create a reference to be signed.
   Reference^ reference = gcnew Reference;
   reference->Uri = L"";
   
   // 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 )
{
   
   // 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();
}


// Create example data to sign.
static void CreateSomeXml( String^ FileName )
{
   
   // Create a new XmlDocument object.
   XmlDocument^ document = gcnew XmlDocument;
   
   // Create a new XmlNode object.
   XmlNode^ node = document->CreateNode( XmlNodeType::Element, L"", L"MyXML", L"Don't_Sign" );
   
   // Append the node to the document.
   document->AppendChild( node );
   
   // Create a new XmlNode object.
   XmlNode^ subnode = document->CreateNode( XmlNodeType::Element, L"", L"TempElement", L"Sign" );
   
   // Add some text to the node.
   subnode->InnerText = L"Here is some data to sign.";
   
   // Append the node to the document.
   document->DocumentElement->AppendChild( subnode );
   
   // 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( L"Example.xml" );
      Console::WriteLine( L"New XML file created." );
      
      // Sign the XML that was just created and save it in a 
      // new file.
      SignXmlFile( L"Example.xml", L"SignedExample.xml", Key );
      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 );
   }

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

public class SignVerifyEnvelope
{

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

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

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

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

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

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

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

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

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

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

        // Specify a canonicalization method.
        signedXml.SignedInfo.CanonicalizationMethod = SignedXml.XmlDsigExcC14NTransformUrl;

        // Set the InclusiveNamespacesPrefixList property.
        XmlDsigExcC14NTransform canMethod = (XmlDsigExcC14NTransform)signedXml.SignedInfo.CanonicalizationMethodObject;
        canMethod.InclusiveNamespacesPrefixList = "Sign";

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        // Create a new XmlNode object.
        XmlNode node = document.CreateNode(XmlNodeType.Element, "", "MyXML", "Don't_Sign");

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

        // Create a new XmlNode object.
        XmlNode subnode = document.CreateNode(XmlNodeType.Element, "", "TempElement", "Sign");

        // Add some text to the node.
        subnode.InnerText = "Here is some data to sign.";

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

        // 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



Module SignVerifyEnvelope


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

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

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

            ' Verify the signature of the signed XML.
            Console.WriteLine("Verifying signature...")
            Dim result As Boolean = VerifyXmlFile("SignedExample.xml")

            ' Display the results of the signature verification to 
            ' the console.
            If result Then
                Console.WriteLine("The XML signature is valid.")
            Else
                Console.WriteLine("The XML signature is not valid.")
            End If

        Catch e As CryptographicException
            Console.WriteLine(e.Message)
        End Try

    End Sub


    ' Sign an XML file and save the signature in a new file.
    Sub SignXmlFile(ByVal FileName As String, ByVal SignedFileName As String, ByVal Key As RSA)
        ' Create a new XML document.
        Dim doc As New XmlDocument()

        ' Format the document to ignore white spaces.
        doc.PreserveWhitespace = False

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

        ' Create a SignedXml object.
        Dim signedXml As New SignedXml(doc)

        ' Add the key to the SignedXml document. 
        signedXml.SigningKey = Key

        ' Specify a canonicalization method.
        signedXml.SignedInfo.CanonicalizationMethod = signedXml.XmlDsigExcC14NTransformUrl

        ' Set the InclusiveNamespacesPrefixList property. 
        Dim canMethod As XmlDsigExcC14NTransform = CType(signedXml.SignedInfo.CanonicalizationMethodObject, XmlDsigExcC14NTransform)
        canMethod.InclusiveNamespacesPrefixList = "Sign"

        ' Create a reference to be signed.
        Dim reference As New Reference()
        reference.Uri = ""

        ' Add an enveloped transformation to the reference.
        Dim env As New XmlDsigEnvelopedSignatureTransform()
        reference.AddTransform(env)

        ' Add the reference to the SignedXml object.
        signedXml.AddReference(reference)


        ' Add an RSAKeyValue KeyInfo (optional; helps recipient find key to validate).
        Dim keyInfo As New KeyInfo()
        keyInfo.AddClause(New RSAKeyValue(CType(Key, RSA)))
        signedXml.KeyInfo = keyInfo

        ' Compute the signature.
        signedXml.ComputeSignature()

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

        ' Append the element to the XML document.
        doc.DocumentElement.AppendChild(doc.ImportNode(xmlDigitalSignature, True))


        If TypeOf doc.FirstChild Is XmlDeclaration Then
            doc.RemoveChild(doc.FirstChild)
        End If

        ' Save the signed XML document to a file specified
        ' using the passed string.
        Dim xmltw As New XmlTextWriter(SignedFileName, New UTF8Encoding(False))
        doc.WriteTo(xmltw)
        xmltw.Close()

    End Sub

    ' Verify the signature of an XML file and return the result.
    Function VerifyXmlFile(ByVal Name As String) As [Boolean]
        ' Create a new XML document.
        Dim xmlDocument As New XmlDocument()

        ' Format using white spaces.
        xmlDocument.PreserveWhitespace = True

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

        ' Create a new SignedXml object and pass it
        ' the XML document class.
        Dim signedXml As New SignedXml(xmlDocument)

        ' Find the "Signature" node and create a new
        ' XmlNodeList object.
        Dim nodeList As XmlNodeList = xmlDocument.GetElementsByTagName("Signature")

        ' Load the signature node.
        signedXml.LoadXml(CType(nodeList(0), XmlElement))

        ' Check the signature and return the result.
        Return signedXml.CheckSignature()

    End Function


    ' Create example data to sign.
    Sub CreateSomeXml(ByVal 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, "", "MyXML", "Don't_Sign")

        ' Append the node to the document.
        document.AppendChild(node)

        ' Create a new XmlNode object.
        Dim subnode As XmlNode = document.CreateNode(XmlNodeType.Element, "", "TempElement", "Sign")

        ' Add some text to the node.
        subnode.InnerText = "Here is some data to sign."

        ' Append the node to the document.
        document.DocumentElement.AppendChild(subnode)

        ' 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 Module

Comentários

A classe XmlDsigExcC14NTransform representa a transformação de canonização C14N XML exclusiva sem comentários. Essa classe é semelhante à classe XmlDsigC14NTransform, que permite que um signatário crie um resumo usando a forma canônica de um documento XML. No entanto, a classe XmlDsigExcC14NTransform exclui o contexto ancestral de um subdocumento canônico.

Use a classe XmlDsigC14NTransform quando precisar canonizar um subdocumento XML para que ele seja independente de seu contexto XML. Por exemplo, aplicativos como serviços Web que usam XML assinado em protocolos de comunicação complexos geralmente precisam canonizar XML dessa maneira. Esses aplicativos geralmente codificam XML em vários elementos construídos dinamicamente, o que pode alterar substancialmente o documento e fazer com que a verificação de assinatura XML falhe. A classe XmlDsigExcC14NTransform resolve esse problema excluindo esse contexto ancestral do subdocumento canônico.

Normalmente, você não cria uma nova instância de uma classe de transformação de canonicalização. Para especificar uma transformação de canonicalização, passe o URI (Uniform Resource Identifier) que descreve uma transformação para a propriedade CanonicalizationMethod, que é acessível a partir da propriedade SignedInfo. Para adquirir uma referência à transformação de canonicalização, use a propriedade CanonicalizationMethodObject, que é acessível a partir da propriedade SignedInfo.

Você deve criar uma nova instância de uma classe de transformação de canonicalização somente quando quiser hash manual de um documento XML ou usar seu próprio algoritmo de canonicalização.

O URI que descreve a classe XmlDsigExcC14NWithCommentsTransform é definido pelo campo XmlDsigExcC14NWithCommentsTransformUrl.

O URI que descreve a classe XmlDsigExcC14NTransform é definido pelo campo XmlDsigExcC14NTransformUrl.

Para obter mais informações sobre a transformação C14N exclusiva, consulte a especificação W3C XMLDSIG. O algoritmo de canonicalização é definido na especificação XML canônica do W3C .

Construtores

XmlDsigExcC14NTransform()	Inicializa uma nova instância da classe XmlDsigExcC14NTransform.
XmlDsigExcC14NTransform(Boolean, String)	Inicializa uma nova instância da classe XmlDsigExcC14NTransform especificando se os comentários devem ser incluídos e especificando uma lista de prefixos de namespace.
XmlDsigExcC14NTransform(Boolean)	Inicializa uma nova instância da classe XmlDsigExcC14NTransform especificando um valor que determina se os comentários devem ser incluídos.
XmlDsigExcC14NTransform(String)	Inicializa uma nova instância da classe XmlDsigExcC14NTransform especificando uma lista de prefixos de namespace para canonizar usando o algoritmo de canonicalização padrão.

Propriedades

Algorithm	Obtém ou define o URI (Uniform Resource Identifier) que identifica o algoritmo executado pela transformação atual. (Herdado de Transform)
Context	Obtém ou define um objeto XmlElement que representa o contexto do documento no qual o objeto Transform atual está em execução. (Herdado de Transform)
InclusiveNamespacesPrefixList	Obtém ou define uma cadeia de caracteres que contém prefixos de namespace para canonicalizar usando o algoritmo de canonicalização padrão.
InputTypes	Obtém uma matriz de tipos que são entradas válidas para o método LoadInput(Object) do objeto XmlDsigExcC14NTransform atual.
OutputTypes	Obtém uma matriz de tipos que são possíveis saídas dos métodos GetOutput() do objeto XmlDsigExcC14NTransform atual.
PropagatedNamespaces	Obtém ou define um objeto Hashtable que contém os namespaces propagados para a assinatura. (Herdado de Transform)
Resolver	Define o objeto XmlResolver atual. (Herdado de Transform)

Métodos

Equals(Object)	Determina se o objeto especificado é igual ao objeto atual. (Herdado de Object)
GetDigestedOutput(HashAlgorithm)	Retorna o resumo associado a um objeto XmlDsigExcC14NTransform.
GetHashCode()	Serve como a função de hash padrão. (Herdado de Object)
GetInnerXml()	Retorna uma representação XML dos parâmetros de um objeto XmlDsigExcC14NTransform que são adequados para serem incluídos como subelementos de um elemento <Transform> XMLDSIG.
GetOutput()	Retorna a saída do objeto XmlDsigExcC14NTransform atual.
GetOutput(Type)	Retorna a saída do objeto XmlDsigExcC14NTransform atual como um objeto do tipo especificado.
GetType()	Obtém o Type da instância atual. (Herdado de Object)
GetXml()	Retorna a representação XML do objeto Transform atual. (Herdado de Transform)
LoadInnerXml(XmlNodeList)	Analisa o objeto XmlNodeList especificado como conteúdo específico da transformação de um elemento <Transform> e configura o estado interno do objeto XmlDsigExcC14NTransform atual para corresponder ao elemento <Transform>.
LoadInput(Object)	Quando substituído em uma classe derivada, carrega a entrada especificada no objeto XmlDsigExcC14NTransform atual.
MemberwiseClone()	Cria uma cópia superficial do Objectatual. (Herdado de Object)
ToString()	Retorna uma cadeia de caracteres que representa o objeto atual. (Herdado de Object)