public ActionResult Index(SignatureStartModel model)
{
byte[] toSignHash, transferData;
SignatureAlgorithm signatureAlg;
try {
// Instantiate a XmlElementSigner class
var signer = new XmlElementSigner();
// Set the data to sign, which in the case of this example is a fixed sample document
signer.SetXml(StorageMock.GetSampleNFeContent());
// static Id from node <infNFe> from SampleNFe.xml document
signer.SetToSignElementId("NFe35141214314050000662550010001084271182362300");
// Decode the user's certificate and set as the signer certificate
signer.SetSigningCertificate(PKCertificate.Decode(model.CertContent));
// Set the signature policy
signer.SetPolicy(getSignaturePolicy());
// Generate the "to-sign-hash". This method also yields the signature algorithm that must
// be used on the client-side, based on the signature policy.
toSignHash = signer.GenerateToSignHash(out signatureAlg, out transferData);
} catch (ValidationException ex) {
// Some of the operations above may throw a ValidationException, for instance if the certificate
// encoding cannot be read or if the certificate is expired.
ModelState.AddModelError("", ex.ValidationResults.ToString());
return(View());
}
// On the next step (Complete action), we'll need once again some information:
// - The thumpprint of the selected certificate.
// - The "transfer data" used to validate the signature in complete action.Its content is stored in
// a temporary file (with extension .bin) to be shared with the Complete action.
// - The "to-sign-hash" to be signed. (see signature-complete-form.js)
// - The OID of the digest algorithm to be used during the signature operation.
// We'll store this value on TempData, that will store in dictionary shared between actions.
TempData["SignatureCompleteModel"] = new SignatureCompleteModel()
{
CertThumb = model.CertThumb,
TransferDataFileId = StorageMock.Store(transferData, ".bin"),
ToSignHash = toSignHash,
DigestAlgorithmOid = signatureAlg.DigestAlgorithm.Oid
};
return(RedirectToAction("Complete"));
}
public ActionResult Complete(SignatureCompleteModel model)
{
byte[] signatureContent;
try {
// Recover the "transfer data" content stored in a temporary file.
byte[] transferDataContent;
if (!StorageMock.TryGetFile(model.TransferDataFileId, out transferDataContent))
{
return(HttpNotFound());
}
// Instantiate a XmlElementSigner class
var signer = new XmlElementSigner();
// Set the document to be signed and the policy, exactly like in the Start method
signer.SetXml(StorageMock.GetSampleNFeContent());
signer.SetPolicy(getSignaturePolicy());
// Set the signature computed on the client-side, along with the "transfer data" (rendered in a hidden field, see the view)
signer.SetPrecomputedSignature(model.Signature, transferDataContent);
// Call ComputeSignature(), which does all the work, including validation of the signer's certificate and of the resulting signature
signer.ComputeSignature();
// Get the signed XML as an array of bytes
signatureContent = signer.GetSignedXml();
} catch (ValidationException ex) {
// Some of the operations above may throw a ValidationException, for instance if the certificate is revoked.
ModelState.AddModelError("", ex.ValidationResults.ToString());
return(View());
}
// On the next step (SignatureInfo action), we'll render the following information:]
// - The filename to be available to download in next action.
// - The signer's certificate information to be rendered.
// We'll store these values on TempData, which is a dictionary shared between actions.
TempData["SignatureInfoModel"] = new SignatureInfoModel()
{
// Store the signature file on the folder "App_Data/" and redirects to the SignatureInfo action with the filename.
// With this filename, it can show a link to download the signature file.
File = StorageMock.Store(signatureContent, ".xml")
};
return(RedirectToAction("SignatureInfo"));
}
