我试图通过在方法中传递 false 作为第二个参数来验证签名和证书 - SignedXml.CheckSignature(Cert,false) 但是，即使使用的证书（由 makecert 创建，如下例所示）是未过期，CheckSignature() 始终返回 false。
如果您将 false （仅验证签名）作为第二个参数传递，它会返回 true。所以，现在的问题是 - verifySignatureOnly 参数 - 如果指定为 false - 它实际上在证书中检查什么？它是否将证书的到期日期作为确定证书有效性的标准？
下面的代码取自MSDN 页面
//
// 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 01/01/2015 -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.");
}
Console.ReadLine();
}
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.PrivateKey;
// 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 asymetric
// 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, false);
}
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.