/// <summary>
/// Tries to sign the specified XML text.
/// </summary>
/// <param name="xmlText">The XML text.</param>
/// <param name="certificate">The certificate.</param>
/// <param name="elementName">The name of the element to be signed.</param>
/// <param name="elementNamespace">The namespace of the element to be signed.</param>
/// <param name="xmlTextSigned">The initial XML text to which the signature was added.</param>
/// <param name="useFingerprint">If true the public key of the certificate will be replaced with the fingerprint in the signature.</param>
/// <returns>True if the signing was possible, false otherwise.</returns>
public static bool TrySignElement(string xmlText, X509Certificate2 certificate, string elementName, string elementNamespace, out string xmlTextSigned, bool useFingerprint = true)
{
xmlTextSigned = null;
var xmlWholeDocument = new XmlDocument();
xmlWholeDocument.PreserveWhitespace = true;
xmlWholeDocument.LoadXml(xmlText);
if (String.IsNullOrEmpty(elementName))
{
return(false);
}
if (String.IsNullOrEmpty(elementNamespace))
{
return(false);
}
// we are signing only an element (part of the big document)
var elements = xmlWholeDocument.GetElementsByTagName(elementName, elementNamespace);
if (elements.Count == 0)
{
return(false);
}
var elementToSign = elements[0] as XmlElement;
var xmlElementDocument = new XmlDocument();
xmlElementDocument.PreserveWhitespace = true;
xmlElementDocument.LoadXml(elementToSign.OuterXml);
EmandatesSignatureOperationsService.GetOrCreateContextForSignatureAdding getOrCreateContextForSignatureAdding = (doc, elem) =>
{
return(GetOrCreateContextForEmandatesSignatureAdding(doc, elem));
};
//todo cip!! you can optimize this one
XmlElement signatureContainer = getOrCreateContextForSignatureAdding(xmlElementDocument, xmlElementDocument.DocumentElement);
XmlSignature.Sign(ref xmlElementDocument, certificate, signatureContainer, "", useFingerprint);
//var xmlSignature = XmlSignature.Sign(ref doc, certificate, xmlContainerElement, "", null, true);
var newnode = xmlWholeDocument.ImportNode(xmlElementDocument.DocumentElement, true);
elementToSign.ParentNode.ReplaceChild(newnode, elementToSign);
var stringWriter = new StringWriter();
var xmlTextWriter = XmlWriter.Create(stringWriter);
xmlWholeDocument.WriteTo(xmlTextWriter);
xmlTextWriter.Flush();
xmlTextSigned = stringWriter.GetStringBuilder().ToString();
return(true);
}
/// <summary>
/// Verifies the specified XML text signature.
/// </summary>
/// <param name="xmlText">The XML text.</param>
/// <param name="certificate">The certificate.</param>
///<returns>True if the signature is valid, false otherwise</returns>
public static bool VerifyDocument(string xmlText, X509Certificate2 certificate)
{
var xmlDoc = new XmlDocument();
xmlDoc.PreserveWhitespace = true;
xmlDoc.LoadXml(xmlText);
XmlElement signatureElement = XmlSignature.GetElementUnderRoot(xmlDoc.DocumentElement, "Signature", "http://www.w3.org/2000/09/xmldsig#") as XmlElement;
var result = XmlSignature.CheckSignature(xmlDoc, certificate, signatureElement);
return(result);
}
/// <summary>
/// Signs the specified XML text.
/// </summary>
/// <param name="xmlText">The XML text.</param>
/// <param name="certificate">The certificate.</param>
/// <param name="useFingerprint">If true the public key of the certificate will be replaced with the fingerprint in the signature.</param>
/// <returns>The initial XML text to which the signature was added.</returns>
public static string SignDocument(string xmlText, X509Certificate2 certificate, bool useFingerprint = true)
{
var xmlDoc = new XmlDocument();
xmlDoc.PreserveWhitespace = true;
xmlDoc.LoadXml(xmlText);
XmlSignature.Sign(ref xmlDoc, certificate, xmlDoc.DocumentElement, "", useFingerprint);
var stringWriter = new StringWriter();
var xmlTextWriter = XmlWriter.Create(stringWriter);
xmlDoc.WriteTo(xmlTextWriter);
xmlTextWriter.Flush();
xmlText = stringWriter.GetStringBuilder().ToString();
return(xmlText);
}
private static XmlElement GetOrCreateContextForEmandatesSignatureAdding(XmlDocument xmlDocument, XmlElement xmlElement)
{
XmlNode mndtAccptncRptNode = XmlSignature.GetElementUnderRoot(xmlElement, "MndtAccptncRpt");
if (mndtAccptncRptNode == null)
{
return(null);
}
// the signature should be placed inside the signed element (more specific, inside a <SplmtryData><Envlp>....</Envlp></SplmtryData> container)
string elemPrefix = !String.IsNullOrEmpty(xmlDocument.Prefix) ? xmlDocument.Prefix + ":" : "";
var splmtryDataElements = xmlDocument.GetElementsByTagName("SplmtryData");
var envlpDataElements = xmlDocument.GetElementsByTagName("Envlp");
XmlElement splmtryDataContainer;
if (splmtryDataElements.Count == 0)
{
splmtryDataContainer = xmlDocument.CreateElement(elemPrefix + "SplmtryData", xmlElement.NamespaceURI);
// append the 'SplmtryData' element at the end of the signed element
mndtAccptncRptNode.AppendChild(splmtryDataContainer);
}
else
{
splmtryDataContainer = splmtryDataElements[0] as XmlElement;
}
XmlElement envlpContainer;
if (envlpDataElements.Count == 0)
{
envlpContainer = xmlDocument.CreateElement(elemPrefix + "Envlp", xmlElement.NamespaceURI);
// append the 'Envlp' into the 'SplmtryData' element
splmtryDataContainer.AppendChild(envlpContainer);
}
else
{
envlpContainer = envlpDataElements[0] as XmlElement;
}
return(envlpContainer);
}
private static XmlElement GetEmandatesSignatureElement(XmlElement xmlElement)
{
XmlNode mndtAccptncRptElement = XmlSignature.GetElementUnderRoot(xmlElement, "MndtAccptncRpt");
if (mndtAccptncRptElement != null)
{
XmlNode splmtryDataElement = XmlSignature.GetElementUnderRoot(mndtAccptncRptElement as XmlElement, "SplmtryData");
if (splmtryDataElement != null)
{
XmlNode envlpElement = XmlSignature.GetElementUnderRoot(splmtryDataElement as XmlElement, "Envlp");
if (envlpElement != null)
{
var sig = XmlSignature.GetElementUnderRoot(envlpElement as XmlElement, "Signature", "http://www.w3.org/2000/09/xmldsig#") as XmlElement;
return(sig);
}
}
}
return(null);
}
/// <summary>
/// Tries to verify the specified XML text signature.
/// </summary>
/// <param name="xmlText">The XML text.</param>
/// <param name="elementName">The name of the element signature to be verified.</param>
/// <param name="elementNamespace">The namespace of the element signature to be verified.</param>
/// <param name="isValidSignature">True if the signature is valid and placed properly, false otherwise.</param>
/// <returns>True if the verifying was possible, false otherwise.</returns>
public static bool TryVerifyElement(string xmlText, string elementName, string elementNamespace, out bool isValidSignature)
{
isValidSignature = false;
if (String.IsNullOrEmpty(elementName))
{
return(false);
}
var xmlDoc = new XmlDocument();
xmlDoc.PreserveWhitespace = true;
xmlDoc.LoadXml(xmlText);
var elements = xmlDoc.GetElementsByTagName(elementName, elementNamespace);
if (elements.Count == 0)
{
return(false);
}
XmlElement elementToSign = elements[0] as XmlElement;
var xmlElementDoc = new XmlDocument();
xmlElementDoc.PreserveWhitespace = true;
xmlElementDoc.LoadXml(elementToSign.OuterXml);
//XmlElement element = elementToSign;
//var keyInfo = XmlSignature.GetElementUnderRoot(element as XmlElement, "KeyInfo");
//var x509Data = XmlSignature.GetElementUnderRoot(keyInfo as XmlElement, "X509Data");
//var x509Certificate = XmlSignature.GetElementUnderRoot(x509Data as XmlElement, "X509Certificate");
//byte[] certificate = Encoding.Unicode.GetBytes(x509Certificate.InnerText);
X509Certificate2 cert = ExtractCertificate(xmlElementDoc);
// the signature should have been placed inside its 'MndtAccptncRpt' element (more specific, inside a <SplmtryData><Envlp>....</Envlp></SplmtryData> container)
isValidSignature = XmlSignature.CheckSignature(xmlElementDoc, cert,
GetEmandatesSignatureElement(xmlElementDoc.DocumentElement));
return(true);
}
static EmandatesSignatureOperationsService()
{
XmlSignature.RegisterSignatureAlghorighm();
}
