如何使用X509证书对xml进行签名,将摘要值和签名添加到xml模板

我对C#很陌生,尤其是对X509签名很陌生。我有一个xml模板,我必须在其中添加使用的证书(完成),并对时间戳(TS-1)、二进制安全令牌和主体(id-1)进行签名。 此外,我需要用这3个元素的摘要值写入(例如替换占位符)并添加签名值。

然而,我并不真正理解这个概念,例如如何做到这一点。我读了几个网站,例如。 signing a xml document with x509 certificate 但我无法使代码适应我的问题。

以下是我尝试的:

public static string SignXml(string template)
{

    XmlDocument document = new XmlDocument();
    document.LoadXml(template);

        // define elements that will be signed
        XmlNode securityToken = null;
        XmlNode validityPeriod = null;
        XmlNode body = null;
        XmlNode signedInfo = null;
        XmlNode signatureValue = null;
        XmlNodeList digestTags = null;



        XmlNamespaceManager namespaces = new XmlNamespaceManager(document.NameTable);
        namespaces.AddNamespace("ns", "http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd");
        namespaces.AddNamespace("nu", "http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd");
        namespaces.AddNamespace("bo", "http://schemas.xmlsoap.org/soap/envelope/");
        namespaces.AddNamespace("si", "http://www.w3.org/2000/09/xmldsig#");
        namespaces.AddNamespace("sinfo", "soapenv xd xe");

        document.LoadXml(template);
        //XmlNode idNode = document.SelectSingleNode("/My_RootNode/ns:id", namespaces);

        securityToken = document.SelectSingleNode("descendant::ns:BinarySecurityToken", namespaces);
        validityPeriod = document.SelectSingleNode("descendant::nu:Timestamp", namespaces);
        body = document.SelectSingleNode("descendant::bo:Body", namespaces);
        signedInfo = document.SelectSingleNode("descendant::si:SignedInfo", namespaces);
        signatureValue = document.SelectSingleNode("descendant::si::sinfo:SignatureValue", namespaces);
        digestTags = document.SelectNodes("descendant::si:DigestValue", namespaces);

        // add the digests (to know where to write the digests)
        String nodeName = null;
        for (int counter = 0; counter < digestTags.Count; counter++)
        {
            nodeName = digestTags[counter].FirstChild.InnerText;
            if (WebserviceConstants.PLACEHOLDER_AUTHNREQUEST_DIGEST.Equals(nodeName))
            {

                generateDigest(body, digestTags[counter]);
            }
            else if (WebserviceConstants.PLACEHOLDER_CERTIFICATE_DIGEST.Equals(nodeName))
            {

                generateDigest(securityToken, digestTags[counter]);
            }
            else if (WebserviceConstants.PLACEHOLDER_TIMESTAMP_TAG_DIGEST.Equals(nodeName))
            {

                generateDigest(validityPeriod, digestTags[counter]);
            }
        }



        SignedXml signedXml = new SignedXml(document);



    X509Certificate2 cert = new X509Certificate2();
    cert = getbase();

    signedXml.SigningKey = cert.PrivateKey;

    // Create a reference to be signed.
    Reference reference = new Reference();
    reference.Uri = "#TS-1";

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

    //canonicalize
    XmlDsigC14NTransform c14t = new XmlDsigC14NTransform();
    reference.AddTransform(c14t);

    KeyInfo keyInfo = new KeyInfo();
    KeyInfoX509Data keyInfoData = new KeyInfoX509Data(cert);
    KeyInfoName kin = new KeyInfoName();
    kin.Value = "Public key of certificate";
    RSACryptoServiceProvider rsaprovider = (RSACryptoServiceProvider)cert.PublicKey.Key;
    RSAKeyValue rkv = new RSAKeyValue(rsaprovider);
    keyInfo.AddClause(kin);
    keyInfo.AddClause(rkv);
    keyInfo.AddClause(keyInfoData);
    signedXml.KeyInfo = keyInfo;

    // 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();

    document.DocumentElement.AppendChild(
    document.ImportNode(xmlDigitalSignature, true));
    document.DocumentElement.AppendChild(document.ImportNode(xmlDigitalSignature, true));

        return document.OuterXml;
    }
}

我在自问:

• 如何获取摘要值以及如何将其写入相应的xml节点
• 如何计算签名值,因为它“包含”所有3个引用的签名信息???

如你所见,我缺少一些一般背景和理解。如果你能帮我,那就太好了!

非常感谢。