Stream Sign(Certificate certificate, IList <Certificate> chain, DigestAlgorithm digestAlgo, Stream content, bool detach)
{
var signerInfo = new CmsSignerInfo();
var signers = new CmsSignerInfo[1];
byte[] signedData;
IBuffer buffer;
signerInfo.HashAlgorithmName = GetHashAlgorithmName(digestAlgo);
signerInfo.Certificate = certificate;
signers[0] = signerInfo;
if (detach)
{
using (var input = content.AsInputStream())
buffer = CmsDetachedSignature.GenerateSignatureAsync(input, signers, chain).GetResults();
}
else
{
buffer = CryptographicBuffer.CreateFromByteArray(ReadAllBytes(content));
buffer = CmsAttachedSignature.GenerateSignatureAsync(buffer, signers, chain).GetResults();
}
CryptographicBuffer.CopyToByteArray(buffer, out signedData);
return(new MemoryStream(signedData, false));
}
/// <summary>
/// This is the click handler for the 'RunSample' button. It is responsible for executing the sample code.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private async void RunSample_Click(object sender, RoutedEventArgs e)
{
Certificate selectedCertificate = null;
string verifyselection = VerifyCert.SelectionBoxItem.ToString();
//get the selected certificate
if (CertificateList.SelectedIndex >= 0 && CertificateList.SelectedIndex < certList.Count)
{
selectedCertificate = certList[CertificateList.SelectedIndex];
}
if (selectedCertificate == null)
{
ViewCertText.Text = "Please select a certificate first.";
return;
}
// a certificate was selected, do the desired operation
if (verifyselection.Equals("Verify Certificate"))
{
//Build the chain
var chain = await selectedCertificate.BuildChainAsync(null, null);
//Validate the chain
var result = chain.Validate();
verifytext = "\n Verification Result :" + result.ToString();
}
else if (verifyselection.Equals("Sign/Verify using certificate key"))
{
// get private key
CryptographicKey keyPair = await PersistedKeyProvider.OpenKeyPairFromCertificateAsync(selectedCertificate, HashAlgorithmNames.Sha1, CryptographicPadding.RsaPkcs1V15);
String cookie = "Some Data to sign";
IBuffer Data = CryptographicBuffer.ConvertStringToBinary(cookie, BinaryStringEncoding.Utf16BE);
try
{
//sign the data by using the key
IBuffer Signed = CryptographicEngine.Sign(keyPair, Data);
bool bresult = CryptographicEngine.VerifySignature(keyPair, Data, Signed);
if (bresult == true)
{
verifytext = "\n Verification Result : Successfully signed and verified signature";
}
else
{
verifytext = "\n Verification Result : Verify Signature Failed";
}
}
catch (Exception exp)
{
verifytext = "\n Verification Failed. Exception Occurred :" + exp.Message;
}
}
else if (verifyselection.Equals("Sign/Verify using CMS based format"))
{
IInputStream pdfInputstream;
InMemoryRandomAccessStream originalData = new InMemoryRandomAccessStream();
//Populate the new memory stream
pdfInputstream = originalData.GetInputStreamAt(0);
CmsSignerInfo signer = new CmsSignerInfo();
signer.Certificate = selectedCertificate;
signer.HashAlgorithmName = HashAlgorithmNames.Sha1;
IList <CmsSignerInfo> signers = new List <CmsSignerInfo>();
signers.Add(signer);
try
{
IBuffer signature = await CmsDetachedSignature.GenerateSignatureAsync(pdfInputstream, signers, null);
CmsDetachedSignature cmsSignedData = new CmsDetachedSignature(signature);
pdfInputstream = originalData.GetInputStreamAt(0);
SignatureValidationResult validationResult = await cmsSignedData.VerifySignatureAsync(pdfInputstream);
if (SignatureValidationResult.Success == validationResult)
{
verifytext = "\n Verification Result : Successfully signed and verified Signature";
}
else
{
verifytext = "\n Verification Result : Verify Signature using CMS based format Failed";
}
}
catch (Exception exp)
{
verifytext = "\n Verification Failed. Exception Occurred :" + exp.Message;
}
}
else if (verifyselection.Equals("Get certificate and show details"))
{
DisplayCertificate(selectedCertificate);
}
ViewCertText.Text += verifytext;
verifytext = string.Empty;
}