XmlDsigC14NTransform Class
Assembly: System.Security (in system.security.dll)
The XmlDsigC14NTransform class represents the C14N XML canonicalization transform that describes the canonical form of an XML document. This transform allows a signer to create a digest (used to create a digital signature) using the canonical form of an XML document. A recipient can then verify the XML digital signature using the same canonical form of the XML document with the same transform.
Use the XmlDsigC14NTransform class when you need to sign an XML document that does not contain comments.
Note that you cannot directly create a new instance of a canonicalization transform class. To specify a canonicalization transform, pass the Uniform Resource Identifier (URI) that describes the transform to the CanonicalizationMethod property, which is accessible from the SignedInfo property. To acquire a reference to the canonicalization transform, use the CanonicalizationMethodObject property, which is accessible from the SignedInfo property.
The URI that describes the XmlDsigC14NTransform class is defined by the XmlDsigC14NTransformUrl field and the XmlDsigCanonicalizationUrl field.
For more information about the C14N transform, see Sections 6.5 and 6.6.1 of the XMLDSIG specification, which is available from the World Wide Web Consortium (W3C) at www.w3.org/TR/xmldsig-core/. The canonicalization algorithm is defined in the W3C Canonical XML specification, which is available at www.w3.org/TR/xml-c14n.
This section contains two code examples. The first example demonstrates how to sign non-XML data using a detached signature. Example #1 creates a signature of www.microsoft.com in an XML file and then verifies the file. The second example demonstrates how to call members of the XmlDsigC14NTransform class.
Example #1
' ' This example signs a file specified by a URI ' using a detached signature. It then verifies ' the signed XML. ' Imports System 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 New RSACryptoServiceProvider() 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 succesfully 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) ' 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 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) ' 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() ' 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) As [Boolean] ' Create a new XML document. Dim xmlDocument As New XmlDocument() ' Load the passed XML 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 and return the result. Return signedXml.CheckSignature() End Function End Class
//
// This example signs a file specified by a URI
// using a detached signature. It then verifies
// the signed XML.
//
import System .* ;
import System.Security.Cryptography .* ;
import System.Security.Cryptography.Xml .* ;
import System.Text .* ;
import System.Xml .* ;
class XMLDSIGDetached
{
/** @attribute STAThread()
*/
public 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.
RSACryptoServiceProvider key = new RSACryptoServiceProvider();
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 succesfully 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.
boolean result = VerifyDetachedSignature(xmlFileName).booleanValue();
// 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.get_Message());
}
} //main
// Sign an XML file and save the signature in a new file.
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.set_SigningKey(key);
// Create a reference to be signed.
Reference reference = new Reference();
// Add the passed URI to the reference object.
reference.set_Uri(uriString);
// Add a transformation if the URI is an XML file.
if (uriString.EndsWith("xml")) {
reference.AddTransform(new XmlDsigC14NTransform());
}
// 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.set_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();
// 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();
} //SignDetachedResource
// Verify the signature of an XML file and return the result.
public static Boolean VerifyDetachedSignature(String xmlSigFileName)
{
// Create a new XML document.
XmlDocument xmlDocument = new XmlDocument();
// Load the passed XML 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.get_ItemOf(0))));
// Check the signature and return the result.
return new Boolean(signedXml.CheckSignature());
} //VerifyDetachedSignature
} //XMLDSIGDetached
Example #2
Imports System Imports System.IO Imports System.Xml Imports System.Security.Cryptography Imports System.Security.Cryptography.Xml Imports System.Security.Cryptography.X509Certificates Public Class Form1 Inherits System.Windows.Forms.Form Private certificateFilePath As String = "..\\my509.cer" ' Event handler for Run button. Private Sub Button1_Click( _ ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button1.Click tbxOutput.Cursor = Cursors.WaitCursor tbxOutput.Text = "" ' Encrypt an XML message Dim productsXml As XmlDocument = LoadProducts() ShowTransformProperties(productsXml) SignDocument(productsXml) ShowTransformProperties(productsXml) ' Use XmlDsigC14NTransform to resolve a Uri. Dim baseUri As New Uri("http://www.contoso.com") Dim relativeUri As String = "xml" Dim absoluteUri As Uri = ResolveUris(baseUri, relativeUri) ' Align interface and conclude application. WriteLine(vbCrLf + "This sample completed successfully;" + _ " press Exit to continue.") ' Reset the cursor. tbxOutput.Cursor = Cursors.Default End Sub ' Encrypt the text in the specified XmlDocument. Private Sub ShowTransformProperties(ByVal xmlDoc As XmlDocument) Dim xmlTransform As New XmlDsigC14NTransform(True) ' Ensure the transform is using the appropriate algorithm. xmlTransform.Algorithm = _ SignedXml.XmlDsigExcC14NTransformUrl ' Retrieve the XML representation of the current transform. Dim xmlInTransform As XmlElement = xmlTransform.GetXml() WriteLine(vbCrLf + "Xml representation of the current transform: ") WriteLine(xmlInTransform.OuterXml) ' Retrieve the valid input types for the current transform. Dim validInTypes() As Type = xmlTransform.InputTypes ' Verify the xmlTransform can accept the XMLDocument as an ' input type. For i As Int16 = 0 To validInTypes.Length Step 1 If (validInTypes(i).Equals(xmlDoc.GetType())) Then ' Load the document into the transfrom. xmlTransform.LoadInput(xmlDoc) Dim secondTransform As New XmlDsigC14NTransform Dim classDescription As String = secondTransform.ToString() ' This call does not perform as expected. ' This transform does not contain inner XML elements secondTransform.LoadInnerXml(xmlDoc.SelectNodes("//.")) Exit For End If Next Dim validOutTypes() As Type = xmlTransform.OutputTypes For i As Int16 = 0 To validOutTypes.Length - 1 Step 1 If (validOutTypes(i).Equals(GetType(System.IO.Stream))) Then Try Dim streamType As Type = GetType(System.IO.Stream) Dim outputStream As MemoryStream outputStream = CType( _ xmlTransform.GetOutput(streamType), _ MemoryStream) ' Read the CryptoStream into a stream reader. Dim streamReader As New StreamReader(outputStream) ' Read the stream into a string. Dim outputMessage As String = streamReader.ReadToEnd() ' Close the streams. outputStream.Close() streamReader.Close() ' Display to the console the Xml before and after ' encryption. WriteLine("Encoding the following xml: " + _ xmlDoc.OuterXml) WriteLine("Message encoded: " + outputMessage) Catch ex As Exception WriteLine("Unexpected exception caught: " + ex.ToString()) End Try Else Dim outputObject As Object = xmlTransform.GetOutput() End If Next End Sub ' Create an XML document describing various products. Private Function LoadProducts() As XmlDocument Dim xmlDoc As New XmlDocument Dim contosoProducts As String = "<PRODUCTS>" contosoProducts += "<PRODUCT><ID>123</ID>" contosoProducts += "<DESCRIPTION>Router</DESCRIPTION></PRODUCT>" contosoProducts += "<PRODUCT><ID>456</ID>" contosoProducts += "<DESCRIPTION>Keyboard</DESCRIPTION></PRODUCT>" ' Include a comment to test the comments feature of the transform. contosoProducts += "<!--Comments are included in the transform-->" ' Include the CDATA tag to test the transform results. contosoProducts += "<PARTNER_URL><![CDATA['http:\\\\www.contoso.com" contosoProducts += "\\partner.asp?h1=en&h2=cr']]></PARTNER_URL>" contosoProducts += "</PRODUCTS>" xmlDoc.LoadXml(contosoProducts) Return xmlDoc End Function ' Create a signature and add it to the specified document. Private Sub SignDocument(ByRef xmlDoc As XmlDocument) ' Generate a signing key. Dim Key As New RSACryptoServiceProvider ' Create a SignedXml object. Dim signedXml As New SignedXml(xmlDoc) ' 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. reference.AddTransform(New XmlDsigC14NTransform) ' Add the reference to the SignedXml object. signedXml.AddReference(reference) Try ' Create a new KeyInfo object. Dim keyInfo As New KeyInfo ' Load the X509 certificate. Dim certificate As X509Certificate certificate = X509Certificate.CreateFromCertFile( _ certificateFilePath) ' Load the certificate into a KeyInfoX509Data object ' and add it to the KeyInfo object. keyInfo.AddClause(New KeyInfoX509Data(certificate)) ' Add the KeyInfo object to the SignedXml object. signedXml.KeyInfo = keyInfo Catch ex As FileNotFoundException WriteLine("Unable to locate the following file: " + _ certificateFilePath) Catch ex As CryptographicException WriteLine("Unexpected exception caught whild creating " + _ "the certificate:" + ex.ToString()) End Try ' Compute the signature. signedXml.ComputeSignature() ' Add the signature branch to the original tree so it is enveloped. xmlDoc.DocumentElement.AppendChild(signedXml.GetXml()) End Sub ' Resolve the specified base and relative Uri's . Private Function ResolveUris( _ ByVal baseUri As Uri, _ ByVal relativeUri As String) As Uri Dim xmlResolver As New XmlUrlResolver xmlResolver.Credentials = _ System.Net.CredentialCache.DefaultCredentials Dim xmlTransform As New XmlDsigC14NTransform xmlTransform.Resolver = xmlResolver Dim absoluteUri As Uri = xmlResolver.ResolveUri(baseUri, relativeUri) If Not absoluteUri Is Nothing Then WriteLine(vbCrLf + _ "Resolved the base Uri and relative Uri to the following:") WriteLine(absoluteUri.ToString()) Else WriteLine("Unable to resolve the base Uri and relative Uri") End If Return absoluteUri End Function ' Write specified message and carriage return to the output textbox. Private Sub WriteLine(ByVal message As String) tbxOutput.AppendText(message + vbCrLf) End Sub ' Event handler for Exit button. Private Sub Button2_Click( _ ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button2.Click Application.Exit() End Sub #Region " Windows Form Designer generated code " Public Sub New() MyBase.New() 'This call is required by the Windows Form Designer. InitializeComponent() 'Add any initialization after the InitializeComponent() call End Sub 'Form overrides dispose to clean up the component list. Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean) If disposing Then If Not (components Is Nothing) Then components.Dispose() End If End If MyBase.Dispose(disposing) End Sub 'Required by the Windows Form Designer Private components As System.ComponentModel.IContainer 'NOTE: The following procedure is required by the Windows Form Designer 'It can be modified using the Windows Form Designer. 'Do not modify it using the code editor. Friend WithEvents Panel2 As System.Windows.Forms.Panel Friend WithEvents Panel1 As System.Windows.Forms.Panel Friend WithEvents Button1 As System.Windows.Forms.Button Friend WithEvents Button2 As System.Windows.Forms.Button Friend WithEvents tbxOutput As System.Windows.Forms.RichTextBox <System.Diagnostics.DebuggerStepThrough()> _ Private Sub InitializeComponent() Me.Panel2 = New System.Windows.Forms.Panel Me.Button1 = New System.Windows.Forms.Button Me.Button2 = New System.Windows.Forms.Button Me.Panel1 = New System.Windows.Forms.Panel Me.tbxOutput = New System.Windows.Forms.RichTextBox Me.Panel2.SuspendLayout() Me.Panel1.SuspendLayout() Me.SuspendLayout() ' 'Panel2 ' Me.Panel2.Controls.Add(Me.Button1) Me.Panel2.Controls.Add(Me.Button2) Me.Panel2.Dock = System.Windows.Forms.DockStyle.Bottom Me.Panel2.DockPadding.All = 20 Me.Panel2.Location = New System.Drawing.Point(0, 320) Me.Panel2.Name = "Panel2" Me.Panel2.Size = New System.Drawing.Size(616, 64) Me.Panel2.TabIndex = 1 ' 'Button1 ' Me.Button1.Dock = System.Windows.Forms.DockStyle.Right Me.Button1.Font = New System.Drawing.Font( _ "Microsoft Sans Serif", _ 9.0!, _ System.Drawing.FontStyle.Regular, _ System.Drawing.GraphicsUnit.Point, _ CType(0, Byte)) Me.Button1.Location = New System.Drawing.Point(446, 20) Me.Button1.Name = "Button1" Me.Button1.Size = New System.Drawing.Size(75, 24) Me.Button1.TabIndex = 2 Me.Button1.Text = "&Run" ' 'Button2 ' Me.Button2.Dock = System.Windows.Forms.DockStyle.Right Me.Button2.Font = New System.Drawing.Font( _ "Microsoft Sans Serif", _ 9.0!, _ System.Drawing.FontStyle.Regular, _ System.Drawing.GraphicsUnit.Point, _ CType(0, Byte)) Me.Button2.Location = New System.Drawing.Point(521, 20) Me.Button2.Name = "Button2" Me.Button2.Size = New System.Drawing.Size(75, 24) Me.Button2.TabIndex = 3 Me.Button2.Text = "E&xit" ' 'Panel1 ' Me.Panel1.Controls.Add(Me.tbxOutput) Me.Panel1.Dock = System.Windows.Forms.DockStyle.Fill Me.Panel1.DockPadding.All = 20 Me.Panel1.Location = New System.Drawing.Point(0, 0) Me.Panel1.Name = "Panel1" Me.Panel1.Size = New System.Drawing.Size(616, 320) Me.Panel1.TabIndex = 2 ' 'tbxOutput ' Me.tbxOutput.AccessibleDescription = _ "Displays output from application." Me.tbxOutput.AccessibleName = "Output textbox." Me.tbxOutput.Dock = System.Windows.Forms.DockStyle.Fill Me.tbxOutput.Location = New System.Drawing.Point(20, 20) Me.tbxOutput.Name = "tbxOutput" Me.tbxOutput.Size = New System.Drawing.Size(576, 280) Me.tbxOutput.TabIndex = 1 Me.tbxOutput.Text = "Click the Run button to run the application." ' 'Form1 ' Me.AutoScaleBaseSize = New System.Drawing.Size(6, 15) Me.ClientSize = New System.Drawing.Size(616, 384) Me.Controls.Add(Me.Panel1) Me.Controls.Add(Me.Panel2) Me.Name = "Form1" Me.Text = "XmlDsigC14NTransform" Me.Panel2.ResumeLayout(False) Me.Panel1.ResumeLayout(False) Me.ResumeLayout(False) End Sub #End Region End Class ' ' This sample produces the following output: ' ' Xml representation of the current transform: ' <Transform Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315" xmlns ' ="http://www.w3.org/2000/09/xmldsig#" /> ' Encoding the following xml: <PRODUCTS><PRODUCT><ID>123</ID><DESCRIPTION>Rout ' er</DESCRIPTION></PRODUCT><PRODUCT><ID>456</ID><DESCRIPTION>Keyboard</DESCRI ' PTION></PRODUCT><!--Comments are included in the transform--><PARTNER_URL><! ' [CDATA['http:\\\\www.contoso.com\\partner.asp?h1=en&h2=cr']]></PARTNER_URL>< ' /PRODUCTS> ' Message encoded: <PRODUCTS><PRODUCT><ID>123</ID><DESCRIPTION>Router</DESCRIP ' TION></PRODUCT><PRODUCT><ID>456</ID><DESCRIPTION>Keyboard</DESCRIPTION></PRO ' DUCT><!--Comments are included in the transform--><PARTNER_URL>'http:\\\\www ' .contoso.com\\partner.asp?h1=en&h2=cr'</PARTNER_URL></PRODUCTS> ' Unable to locate the following file: ..\\my509.cer ' ' Xml representation of the current transform: ' <Transform Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315" xmlns ' ="http://www.w3.org/2000/09/xmldsig#" /> ' Encoding the following xml: <PRODUCTS><PRODUCT><ID>123</ID><DESCRIPTION>Rout ' er</DESCRIPTION></PRODUCT><PRODUCT><ID>456</ID><DESCRIPTION>Keyboard</DESCRI ' PTION></PRODUCT><!--Comments are included in the transform--><PARTNER_URL><! ' [CDATA['http:\\\\www.contoso.com\\partner.asp?h1=en&h2=cr']]></PARTNER_URL>< ' Signature xmlns="http://www.w3.org/2000/09/xmldsig#"><SignedInfo><Canonicali ' zationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315" />< ' SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1" /><Re ' ference URI=""><Transforms><Transform Algorithm="http://www.w3.org/TR/2001/R ' EC-xml-c14n-20010315" /></Transforms><DigestMethod Algorithm="http://www.w3. ' org/2000/09/xmldsig#sha1" /><DigestValue>reODk69AR9ytcttnNovo4tHNr7s=</Diges ' tValue></Reference></SignedInfo><SignatureValue>shFIRZqXidkxzQtZwGa7xqWoS0yF ' GDot63A8v17KZzmfDWTaluGk25fvKJ4Bv4Z1ENxevyQY/wCGzsto9FJUvTXsJ9/jTOwIvRQt1204 ' gJ8SgTex8epH/2xnfvdEqZR8HWJq3X/NixGhMUCpmEFwZMn3V/8qryg8mhYp72jPTFI=</Signat ' ureValue></Signature></PRODUCTS> ' Message encoded: <PRODUCTS><PRODUCT><ID>123</ID><DESCRIPTION>Router</DESCRIP ' TION></PRODUCT><PRODUCT><ID>456</ID><DESCRIPTION>Keyboard</DESCRIPTION></PRO ' DUCT><!--Comments are included in the transform--><PARTNER_URL>'http:\\\\www ' .contoso.com\\partner.asp?h1=en&h2=cr'</PARTNER_URL><Signature><SignedIn ' fo><CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n ' -20010315"></CanonicalizationMethod><SignatureMethod Algorithm="http://www.w ' 3.org/2000/09/xmldsig#rsa-sha1"></SignatureMethod><Reference URI=""><Transfo ' rms><Transform Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315">< ' /Transform></Transforms><DigestMethod Algorithm="http://www.w3.org/2000/09/x ' mldsig#sha1"></DigestMethod><DigestValue>reODk69AR9ytcttnNovo4tHNr7s=</Diges ' tValue></Reference></SignedInfo><SignatureValue>shFIRZqXidkxzQtZwGa7xqWoS0yF ' GDot63A8v17KZzmfDWTaluGk25fvKJ4Bv4Z1ENxevyQY/wCGzsto9FJUvTXsJ9/jTOwIvRQt1204 ' gJ8SgTex8epH/2xnfvdEqZR8HWJq3X/NixGhMUCpmEFwZMn3V/8qryg8mhYp72jPTFI=</Signat ' ureValue></Signature></PRODUCTS> ' ' Resolved the base Uri and relative Uri to the following: ' http://www.contoso.com/xml ' ' This sample completed successfully; press Exit to continue.
import System.*;
import System.IO.*;
import System.Xml.*;
import System.Security.Cryptography.*;
import System.Security.Cryptography.Xml.*;
import System.Security.Cryptography.X509Certificates.*;
class Class1
{
private static String Certificate = "..\\..\\my509.cer";
/** @attribute STAThread()
*/
public static void main(String[] args)
{
// Encrypt an XML message
XmlDocument productsXml = LoadProducts();
ShowTransformProperties(productsXml);
SignDocument(productsXml);
ShowTransformProperties(productsXml);
// Use XmlDsigC14NTransform to resolve a Uri.
Uri baseUri = new Uri("http://www.contoso.com");
String relativeUri = "xml";
Uri absoluteUri = ResolveUris(baseUri, relativeUri);
Console.WriteLine("This sample completed successfully; "
+ "press Enter to exit.");
Console.ReadLine();
} //main
// Encrypt the text in the specified XmlDocument.
private static void ShowTransformProperties(XmlDocument xmlDoc)
{
XmlDsigC14NTransform xmlTransform = new XmlDsigC14NTransform(true);
// Ensure the transform is using the appropriate algorithm.
xmlTransform.set_Algorithm(
SignedXml.XmlDsigExcC14NTransformUrl);
// Retrieve the XML representation of the current transform.
XmlElement xmlInTransform = xmlTransform.GetXml();
Console.WriteLine("\nXml representation of the current transform: ");
Console.WriteLine(xmlInTransform.get_OuterXml());
// Retrieve the valid input types for the current transform.
Type validInTypes[] = xmlTransform.get_InputTypes();
// Verify the xmlTransform can accept the XMLDocument as an
// input type.
for (int i = 0; i < validInTypes.get_Length(); i++) {
if (validInTypes.get_Item(i).Equals(xmlDoc.GetType())) {
// Load the document into the transfrom.
xmlTransform.LoadInput(xmlDoc);
XmlDsigC14NTransform secondTransform
= new XmlDsigC14NTransform();
String classDescription = secondTransform.ToString();
// This call does not perform as expected.
// This transform does not contain inner XML elements
secondTransform.LoadInnerXml(xmlDoc.SelectNodes("//."));
break;
}
}
Type validOutTypes[] = xmlTransform.get_OutputTypes();
for (int i = 0; i < validOutTypes.get_Length(); i++) {
if (validOutTypes.get_Item(i).Equals(
System.IO.Stream.class.ToType())) {
try {
Type streamType = System.IO.Stream.class.ToType();
MemoryStream outputStream = (MemoryStream)xmlTransform.
GetOutput(streamType);
// Read the CryptoStream into a stream reader.
StreamReader streamReader = new StreamReader(outputStream);
// Read the stream into a string.
String outputMessage = streamReader.ReadToEnd();
// Close the streams.
outputStream.Close();
streamReader.Close();
// Display to the console the Xml before and after
// encryption.
Console.WriteLine("Encoding the following xml: "
+ xmlDoc.get_OuterXml());
Console.WriteLine("Message encoded: " + outputMessage);
}
catch (System.Exception ex) {
Console.WriteLine("Unexpected exception caught: "
+ ex.ToString());
}
break;
}
else {
Object outputObject = xmlTransform.GetOutput();
}
}
} //ShowTransformProperties
// Create an XML document describing various products.
private static XmlDocument LoadProducts()
{
XmlDocument xmlDoc = new XmlDocument();
String contosoProducts = "<PRODUCTS>";
contosoProducts += "<PRODUCT><ID>123</ID>";
contosoProducts += "<DESCRIPTION>Router</DESCRIPTION></PRODUCT>";
contosoProducts += "<PRODUCT><ID>456</ID>";
contosoProducts += "<DESCRIPTION>Keyboard</DESCRIPTION></PRODUCT>";
// Include a comment to test the comments feature of the transform.
contosoProducts += "<!--Comments are included in the transform-->";
// Include the CDATA tag to test the transform results.
contosoProducts += "<PARTNER_URL><![CDATA['http:\\\\www.contoso.com";
contosoProducts += "\\partner.asp?h1=en&h2=cr']]></PARTNER_URL>";
contosoProducts += "</PRODUCTS>";
xmlDoc.LoadXml(contosoProducts);
return xmlDoc;
} //LoadProducts
// Create a signature and add it to the specified document.
private static void SignDocument(XmlDocument xmlDoc)
{
// Generate a signing key.
RSACryptoServiceProvider key = new RSACryptoServiceProvider();
// Create a SignedXml object.
SignedXml signedXml = new SignedXml(xmlDoc);
// Add the key to the SignedXml document.
signedXml.set_SigningKey(key);
// Create a reference to be signed.
Reference reference = new Reference();
reference.set_Uri("");
// Add an enveloped transformation to the reference.
reference.AddTransform(new XmlDsigC14NTransform());
// Add the reference to the SignedXml object.
signedXml.AddReference(reference);
try {
// Create a new KeyInfo object.
KeyInfo keyInfo = new KeyInfo();
// Load the X509 certificate.
X509Certificate MSCert = X509Certificate.
CreateFromCertFile(Certificate);
// Load the certificate into a KeyInfoX509Data object
// and add it to the KeyInfo object.
keyInfo.AddClause(new KeyInfoX509Data(MSCert));
// Add the KeyInfo object to the SignedXml object.
signedXml.set_KeyInfo(keyInfo);
}
catch (FileNotFoundException exp) {
Console.WriteLine("Unable to locate the following file: "
+ Certificate);
}
catch (CryptographicException ex) {
Console.WriteLine("Unexpected exception caught whild creating "
+ "the certificate:" + ex.ToString());
}
// Compute the signature.
signedXml.ComputeSignature();
// Add the signature branch to the original tree so it is enveloped.
xmlDoc.get_DocumentElement().AppendChild(signedXml.GetXml());
} //SignDocument
// Resolve the specified base and relative Uri's .
private static Uri ResolveUris(Uri baseUri, String relativeUri)
{
XmlUrlResolver xmlResolver = new XmlUrlResolver();
xmlResolver.set_Credentials(System.Net.CredentialCache.
get_DefaultCredentials());
XmlDsigC14NTransform xmlTransform = new XmlDsigC14NTransform();
xmlTransform.set_Resolver(xmlResolver);
Uri absoluteUri = xmlResolver.ResolveUri(baseUri, relativeUri);
if (absoluteUri != null) {
Console.WriteLine("\nResolved the base Uri and relative "
+ "Uri to the following:");
Console.WriteLine(absoluteUri.ToString());
}
else {
Console.WriteLine("Unable to resolve the base "
+ "Uri and relative Uri");
}
return absoluteUri;
} //ResolveUris
} //Class1
//
// This sample produces the following output:
//
// Xml representation of the current transform:
// <Transform Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315" xmln
// s="http://www.w3.org/2000/09/xmldsig#" />
// Encoding the following xml: <PRODUCTS><PRODUCT><ID>123</ID><DESCRIPTION>Rou
// ter</DESCRIPTION></PRODUCT><PRODUCT><ID>456</ID><DESCRIPTION>Keyboard</DESC
// RIPTION></PRODUCT><!--Comments are included in the transform--><PARTNER_URL
// ><![CDATA['http:\\www.contoso.com\partner.asp?h1=en&h2=cr']]></PARTNER_URL>
// </PRODUCTS>Message encoded: <PRODUCTS><PRODUCT><ID>123</ID><DESCRIPTION>Rou
// ter</DESCRIPTION></PRODUCT><PRODUCT><ID>456</ID><DESCRIPTION>Keyboard</DESC
// RIPTION></PRODUCT><!--Comments are included in the transform--><PARTNER_URL
// >'http:\\www.contoso.com\partner.asp?h1=en&h2=cr'</PARTNER_URL></PRODUC
// TS>
// Xml representation of the current transform:
// <Transform Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315" xmln
// s="http://www.w3.org/2000/09/xmldsig#" />
// Encoding the following xml: <PRODUCTS><PRODUCT><ID>123</ID><DESCRIPTION>Rou
// ter</DESCRIPTION></PRODUCT><PRODUCT><ID>456</ID><DESCRIPTION>Keyboard</DESC
// RIPTION></PRODUCT><!--Comments are included in the transform--><PARTNER_URL
// ><![CDATA['http:\\www.contoso.com\partner.asp?h1=en&h2=cr']]></PARTNER_URL>
// <Signature xmlns="http://www.w3.org/2000/09/xmldsig#"><SignedInfo><Canonica
// lizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"
// /><SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1" /
// ><Reference URI=""><Transforms><Transform Algorithm="http://www.w3.org/TR/2
// 001/REC-xml-c14n-20010315" /></Transforms><DigestMethod Algorithm="http://w
// ww.w3.org/2000/09/xmldsig#sha1" /><DigestValue>BFN2s0/NA2NGgb/R0mvfnNM0Ito=
// </DigestValue></Reference></SignedInfo><SignatureValue>vSfZUG5xHuNxzOSEbQjN
// dtEt1D+O7I1LTJ13RrwLaJSfQPrdT/s8IeaA+idw2f2WGuGrdqMJUddpE4GxfK61HmPQ6S7lBG+
// +ND+YaUYf2AtTRs3SnToXQQrARa/pHVjsKxYHR/9tjy6maHBwxjgjFQABvYZu0gZHYRuXvvfxv0
// 8=</SignatureValue><KeyInfo><X509Data xmlns="http://www.w3.org/2000/09/xmld
// sig#"><X509Certificate>MIICCzCCAXSgAwIBAgIQ5eVQY8pRZ5xBF2WLkYPjijANBgkqhkiG
// 9w0BAQQFADAbMRkwFwYDVQQDExBHcmVnc0NlcnRpZmljYXRlMB4XDTAzMDkxNzIzMzU0N1oXDTM
// 5MTIzMTIzNTk1OVowGzEZMBcGA1UEAxMQR3JlZ3NDZXJ0aWZpY2F0ZTCBnzANBgkqhkiG9w0BAQ
// EFAAOBjQAwgYkCgYEAmFJ4v7rS3BYTXgVW9PgBFfTYAcB/m9mOFCmUrrChcBpoEtu/tSESlNfEH
// pECIdqg9vUrCNSkY08HRn3ueNeBSnSpssWd8/XoOboWLh1nd+79Y5uZd1WOJI4s0XM0MegZgCoJ
// cEEhpxCd/HOPIQvEsbpN/DuFiovZLo+Ek3hHoxMCAwEAAaNQME4wTAYDVR0BBEUwQ4AQaCb19dl
// yf/zSxPVYQZY9AKEdMBsxGTAXBgNVBAMTEEdyZWdzQ2VydGlmaWNhdGWCEOXlUGPKUWecQRdli5
// GD44owDQYJKoZIhvcNAQEEBQADgYEAZuZaFDGDJogh7FuT0hfaMAVlRONv6wWVBJVV++eUo38Xu
// RfJ5nNJ0UnhiV2sEtLobYBPEIrNhuk8skdU0AHgx4ILiA4rR96ifWwxtrFQF+h+DL2ZB7xhwcOJ
// +Pa7IC4wIaEp/oBmmX+JHSzfQt6/If4ohwikfxfljKMyIcMlwl4=</X509Certificate></X50
// 9Data></KeyInfo></Signature></PRODUCTS>
//
// Message encoded: <PRODUCTS><PRODUCT><ID>123</ID><DESCRIPTION>Router</DESCRI
// PTION></PRODUCT><PRODUCT><ID>456</ID><DESCRIPTION>Keyboard</DESCRIPTION></P
// RODUCT><!--Comments are included in the transform--><PARTNER_URL>'http:\\ww
// w.contoso.com\partner.asp?h1=en&h2=cr'</PARTNER_URL><Signature><SignedI
// nfo><CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c1
// 4n-20010315"></CanonicalizationMethod><SignatureMethod Algorithm="http://ww
// w.w3.org/2000/09/xmldsig#rsa-sha1"></SignatureMethod><Reference URI=""><Tra
// nsforms><Transform Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-200103
// 15"></Transform></Transforms><DigestMethod Algorithm="http://www.w3.org/200
// 0/09/xmldsig#sha1"></DigestMethod><DigestValue>BFN2s0/NA2NGgb/R0mvfnNM0Ito=
// </DigestValue></Reference></SignedInfo><SignatureValue>vSfZUG5xHuNxzOSEbQjN
// dtEt1D+O7I1LTJ13RrwLaJSfQPrdT/s8IeaA+idw2f2WGuGrdqMJUddpE4GxfK61HmPQ6S7lBG+
// +ND+YaUYf2AtTRs3SnToXQQrARa/pHVjsKxYHR/9tjy6maHBwxjgjFQABvYZu0gZHYRuXvvfxv0
// 8=</SignatureValue><KeyInfo><X509Data xmlns="http://www.w3.org/2000/09/xmld
// sig#"><X509Certificate>MIICCzCCAXSgAwIBAgIQ5eVQY8pRZ5xBF2WLkYPjijANBgkqhkiG
// 9w0BAQQFADAbMRkwFwYDVQQDExBHcmVnc0NlcnRpZmljYXRlMB4XDTAzMDkxNzIzMzU0N1oXDTM
// 5MTIzMTIzNTk1OVowGzEZMBcGA1UEAxMQR3JlZ3NDZXJ0aWZpY2F0ZTCBnzANBgkqhkiG9w0BAQ
// EFAAOBjQAwgYkCgYEAmFJ4v7rS3BYTXgVW9PgBFfTYAcB/m9mOFCmUrrChcBpoEtu/tSESlNfEH
// pECIdqg9vUrCNSkY08HRn3ueNeBSnSpssWd8/XoOboWLh1nd+79Y5uZd1WOJI4s0XM0MegZgCoJ
// cEEhpxCd/HOPIQvEsbpN/DuFiovZLo+Ek3hHoxMCAwEAAaNQME4wTAYDVR0BBEUwQ4AQaCb19dl
// yf/zSxPVYQZY9AKEdMBsxGTAXBgNVBAMTEEdyZWdzQ2VydGlmaWNhdGWCEOXlUGPKUWecQRdli5
// GD44owDQYJKoZIhvcNAQEEBQADgYEAZuZaFDGDJogh7FuT0hfaMAVlRONv6wWVBJVV++eUo38Xu
// RfJ5nNJ0UnhiV2sEtLobYBPEIrNhuk8skdU0AHgx4ILiA4rR96ifWwxtrFQF+h+DL2ZB7xhwcOJ
// +Pa7IC4wIaEp/oBmmX+JHSzfQt6/If4ohwikfxfljKMyIcMlwl4=</X509Certificate></X50
// 9Data></KeyInfo></Signature></PRODUCTS>
//
// Resolved the base Uri and relative Uri to the following:
// http://www.contoso.com/xml
// This sample completed successfully; press Enter to exit.
System.Security.Cryptography.Xml.Transform
System.Security.Cryptography.Xml.XmlDsigC14NTransform
System.Security.Cryptography.Xml.XmlDsigC14NWithCommentsTransform
Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.