3
I am trying to sign an XML by passing the tag reference, id, XML and certificate.
In a certain situation it doesn’t work, however I never know what situation this is, it is something kind of random.
And now, even though I’m changing the reference.uri to put or not by a underline, he’s not going through the method ComputeSignature().
Could you help me?
public string Assinar(string XMLString, string RefUri, X509Certificate2 _X509Cert, object id, bool assinarTagSignature = true)
{
string xmlResultado = string.Empty;
try
{
string x;
x = _X509Cert.GetKeyAlgorithm().ToString();
//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.
try
{
try
{
doc.LoadXml(XMLString);
}
catch (Exception ex)
{
sResultado = XMLString;
throw new Exception("erro ao ler");
}
//Verifica se a tag a ser assinada existe é única
int qtdeRefUri = doc.GetElementsByTagName(RefUri).Count;
if (qtdeRefUri == 0)
{
//a URI indicada não existe
iResultado = 4;
sResultado = "A tag de assinatura " + RefUri.Trim() + " inexiste";
}
//Exsiste mais de uma tag a ser assinada
else
{
if (qtdeRefUri > 1)
{
//Existe mais de uma URI indicada
iResultado = 5;
sResultado = "A tag de assinatura " + RefUri.Trim() + " não é unica";
}
else
{
try
{
//Create a SignedXml object.
SignedXml signedXml = new SignedXml(doc);
//Add the key to the SignedXml document
signedXml.SigningKey = _X509Cert.PrivateKey;
//Create a reference to be signed
Reference reference = new Reference();
//pega o uri que deve ser assinada
XmlAttributeCollection tagUri = doc.GetElementsByTagName(RefUri).Item(0).Attributes;
if (id.ToString() != "0")
foreach (XmlAttribute _atributo in tagUri)
{
if (_atributo.Name == "Id")
{
reference.Uri = "#" + _atributo.InnerText;
//reference.Uri = _atributo.InnerText;
}
}
else
reference.Uri = "";
/*
foreach (XmlAttribute _atributo in tagUri)
{
if (_atributo.Name == "Id")
{
reference.Uri = "#" + _atributo.InnerText;
}
}
*/
//Add an enveloped transformation to the reference.
XmlDsigEnvelopedSignatureTransform env = new XmlDsigEnvelopedSignatureTransform();
reference.AddTransform(env);
XmlDsigC14NTransform c14 = new XmlDsigC14NTransform();
reference.AddTransform(c14);
//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(_X509Cert));
//Add the KeyInfo object to the SignedXml object.
signedXml.KeyInfo = keyInfo;
signedXml.ComputeSignature();
//Get the XML representation of the signature and save
//it to an XmlElement object.
XmlElement xmlDigitalSignature = signedXml.GetXml();
if (assinarTagSignature)
xmlDigitalSignature.SetAttribute("Id", "Ass_" + id.ToString());
//Append the element to the XML document.
doc.DocumentElement.AppendChild(doc.ImportNode(xmlDigitalSignature, true));
XmlDocument XMLDoc = new XmlDocument();
XMLDoc.PreserveWhitespace = false;
XMLDoc = doc;
xmlResultado = XMLDoc.InnerXml;
}
catch (Exception caught)
{
iResultado = 7;
sResultado = "Erro: Ao assinar o documento - " + caught.Message;
}
}
}
}
catch (Exception caught)
{
iResultado = 3;
sResultado = "XML mal formado - " + caught.Message + " " + XMLString;
}
}
catch (Exception caught)
{
iResultado = 1;
sResultado = sResultado = "Problemas na seleção do certificado digital: " + caught.Message;
}
sResultado = "Arquivo Assinado Com Sucesso";
return xmlResultado;
}