SignedXml.CheckSignatureReturningKey(AsymmetricAlgorithm) Metode
Definisi
Penting
Beberapa informasi terkait produk prarilis yang dapat diubah secara signifikan sebelum dirilis. Microsoft tidak memberikan jaminan, tersirat maupun tersurat, sehubungan dengan informasi yang diberikan di sini.
Menentukan apakah Signature properti memverifikasi menggunakan kunci publik dalam tanda tangan.
public:
bool CheckSignatureReturningKey([Runtime::InteropServices::Out] System::Security::Cryptography::AsymmetricAlgorithm ^ % signingKey);public bool CheckSignatureReturningKey(out System.Security.Cryptography.AsymmetricAlgorithm? signingKey);public bool CheckSignatureReturningKey(out System.Security.Cryptography.AsymmetricAlgorithm signingKey);member this.CheckSignatureReturningKey : AsymmetricAlgorithm -> boolPublic Function CheckSignatureReturningKey (ByRef signingKey As AsymmetricAlgorithm) As BooleanParameter
- signingKey
- AsymmetricAlgorithm
Ketika metode ini kembali, berisi implementasi AsymmetricAlgorithm yang menyimpan kunci publik dalam tanda tangan. Parameter ini diteruskan tanpa diinisialisasi.
Mengembalikan
true
Signature jika properti memverifikasi menggunakan kunci umum dalam tanda tangan; jika tidak, false.
Pengecualian
Parameter signingKey null.
Properti SignatureAlgorithm kunci publik dalam tanda tangan tidak cocok dengan SignatureMethod properti .
-atau-
Deskripsi tanda tangan tidak dapat dibuat.
-Atau
Algoritma hash tidak dapat dibuat.
Contoh
Contoh kode berikut menunjukkan cara menandatangani dokumen XML, memverifikasi tanda tangan dengan menggunakan CheckSignatureReturningKey, lalu mengonfirmasi bahwa kunci yang dikembalikan cocok dengan kunci yang sudah dipercaya aplikasi.
//
// 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)
{
try
{
// Generate a RSA signing key.
RSA RSAKey = 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", RSAKey);
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 RSAKey)
{
// 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 RSA key to the SignedXml document.
signedXml.SigningKey = RSAKey;
// 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 a RSAKeyValue to the KeyInfo (optional; helps recipient find key to validate).
KeyInfo keyInfo = new KeyInfo();
keyInfo.AddClause(new RSAKeyValue((RSA)RSAKey));
signedXml.KeyInfo = keyInfo;
// Compute the signature.
signedXml.ComputeSignature();
// Get the XML representation of the signature and save
// it to an XmlElement object.
XmlElement xmlDigitalSignature = signedXml.GetXml();
// Append the element to the XML document.
doc.DocumentElement.AppendChild(doc.ImportNode(xmlDigitalSignature, true));
if (doc.FirstChild is XmlDeclaration)
{
doc.RemoveChild(doc.FirstChild);
}
// Save the signed XML document to a file specified
// using the passed string.
XmlTextWriter xmltw = new XmlTextWriter(SignedFileName, new UTF8Encoding(false));
doc.WriteTo(xmltw);
xmltw.Close();
}
// Verify the signature of an XML file and return the result.
public static Boolean VerifyXmlFile(String Name)
{
// Create a new XML document.
XmlDocument xmlDocument = new XmlDocument();
// Format using white spaces.
xmlDocument.PreserveWhitespace = true;
// Load the passed XML file into the document.
xmlDocument.Load(Name);
// Create a new SignedXml object and pass it
// the XML document class.
SignedXml signedXml = new SignedXml(xmlDocument);
// Find the "Signature" node and create a new
// XmlNodeList object.
XmlNodeList nodeList = xmlDocument.GetElementsByTagName("Signature");
// Load the signature node.
signedXml.LoadXml((XmlElement)nodeList[0]);
// Check the signature and return the result.
return signedXml.CheckSignature();
}
// Create example data to sign.
public static void CreateSomeXml(string FileName)
{
// Create a new XmlDocument object.
XmlDocument document = new XmlDocument();
// Create a new XmlNode object.
XmlNode node = document.CreateNode(XmlNodeType.Element, "", "MyElement", "samples");
// Add some text to the node.
node.InnerText = "Example text to be signed.";
// Append the node to the document.
document.AppendChild(node);
// Save the XML document to the file name specified.
XmlTextWriter xmltw = new XmlTextWriter(FileName, new UTF8Encoding(false));
document.WriteTo(xmltw);
xmltw.Close();
}
}
'
' This example signs an XML file using an
' envelope signature. It then verifies the
' signed XML.
'
Imports System.Security.Cryptography
Imports System.Security.Cryptography.Xml
Imports System.Text
Imports System.Xml
Public Class SignVerifyEnvelope
Overloads Public Shared Sub Main(args() As [String])
Try
' Generate a RSA signing key.
Dim RSAKey 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", RSAKey)
Console.WriteLine("XML file signed.")
' Verify the signature of the signed XML.
Console.WriteLine("Verifying signature...")
Dim result As Boolean = VerifyXmlFile("SignedExample.xml")
' Display the results of the signature verification to \
' the console.
If result Then
Console.WriteLine("The XML signature is valid.")
Else
Console.WriteLine("The XML signature is not valid.")
End If
Catch e As CryptographicException
Console.WriteLine(e.Message)
End Try
End Sub
' Sign an XML file and save the signature in a new file.
Public Shared Sub SignXmlFile(FileName As String, SignedFileName As String, RSAKey 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 RSA key to the SignedXml document.
signedXml.SigningKey = RSAKey
' 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 a RSAKeyValue to the KeyInfo (optional; helps recipient find key to validate).
Dim keyInfo As New KeyInfo()
keyInfo.AddClause(New RSAKeyValue(CType(RSAKey, RSA)))
signedXml.KeyInfo = keyInfo
' Compute the signature.
signedXml.ComputeSignature()
' Get the XML representation of the signature and save
' it to an XmlElement object.
Dim xmlDigitalSignature As XmlElement = signedXml.GetXml()
' Append the element to the XML document.
doc.DocumentElement.AppendChild(doc.ImportNode(xmlDigitalSignature, True))
If TypeOf doc.FirstChild Is XmlDeclaration Then
doc.RemoveChild(doc.FirstChild)
End If
' Save the signed XML document to a file specified
' using the passed string.
Dim xmltw As New XmlTextWriter(SignedFileName, New UTF8Encoding(False))
doc.WriteTo(xmltw)
xmltw.Close()
End Sub
' Verify the signature of an XML file and return the result.
Public Shared Function VerifyXmlFile(Name As [String]) As [Boolean]
' Create a new XML document.
Dim xmlDocument As New XmlDocument()
' Format using white spaces.
xmlDocument.PreserveWhitespace = True
' Load the passed XML file into the document.
xmlDocument.Load(Name)
' Create a new SignedXml object and pass it
' the XML document class.
Dim signedXml As New SignedXml(xmlDocument)
' Find the "Signature" node and create a new
' XmlNodeList object.
Dim nodeList As XmlNodeList = xmlDocument.GetElementsByTagName("Signature")
' Load the signature node.
signedXml.LoadXml(CType(nodeList(0), XmlElement))
' Check the signature and return the result.
Return signedXml.CheckSignature()
End Function
' Create example data to sign.
Public Shared Sub CreateSomeXml(FileName As String)
' Create a new XmlDocument object.
Dim document As New XmlDocument()
' Create a new XmlNode object.
Dim node As XmlNode = document.CreateNode(XmlNodeType.Element, "", "MyElement", "samples")
' Add some text to the node.
node.InnerText = "Example text to be signed."
' Append the node to the document.
document.AppendChild(node)
' Save the XML document to the file name specified.
Dim xmltw As New XmlTextWriter(FileName, New UTF8Encoding(False))
document.WriteTo(xmltw)
xmltw.Close()
End Sub
End Class
Keterangan
Important
Kunci yang dikembalikan dipilih berdasarkan KeyInfo elemen dokumen yang ditandatanganisigningKey, yang berada di bawah kendali siapa pun yang menghasilkan dokumen.
true Hasilnya hanya membuktikan bahwa bagian dokumen yang ditandatangani cocok dengan tanda tangan yang dihitung dengan kunci yang dikembalikan — bukan kunci milik penanda tangan tepercaya. Kelebihan beban ini tidak cocok untuk mengautentikasi dokumen dari sumber yang tidak tepercaya kecuali pemanggil membandingkan dengan signingKey kunci yang sudah dipercaya aplikasi sebelum memperlakukan dokumen sebagai autentik.
Untuk sebagian besar skenario, lebih suka kelebihan beban yang mengambil kunci verifikasi di depan sehingga kepercayaan ditetapkan sebelum verifikasi:
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