private void browseDSBtn_Click(object sender, EventArgs e)
{
digitalSignPathLabel.Text = string.Empty;
dsInput.Text = string.Empty;
SignaturePath = string.Empty;
using OpenFileDialog openFileDialog = new OpenFileDialog
{
Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*",
FilterIndex = 2,
RestoreDirectory = true
};
if (openFileDialog.ShowDialog() == DialogResult.OK)
{
SignaturePath = openFileDialog.FileName;
digitalSignPathLabel.Text = FilePath;
try
{
var signatureContent = File.ReadAllText(SignaturePath);
var signTuple = DsaSerializer.Deserialize(signatureContent);
dsInput.Text = signTuple.ToString();
} catch (Exception ex)
{
MessageBox.Show("Error: Signature file is corrupt.");
return;
}
}
}
private void verifyBtn_Click(object sender, EventArgs e)
{
dsInput.Text = string.Empty;
if (string.IsNullOrWhiteSpace(FilePath))
{
MessageBox.Show("Error: Choose a file.");
return;
}
if (string.IsNullOrWhiteSpace(SignaturePath))
{
MessageBox.Show("Error: Choose a file with signature.");
return;
}
try
{
var signatureContent = File.ReadAllText(SignaturePath);
var signTuple = DsaSerializer.Deserialize(signatureContent);
dsInput.Text = signTuple.ToString();
var verifyResult = dsa.Verify(MessageBytes, signTuple.Item1, signTuple.Item2);
if (verifyResult)
{
MessageBox.Show("File is valid!");
}
else
{
MessageBox.Show("File is invalid!");
}
}
catch (Exception ex)
{
MessageBox.Show("Error: Signature file is corrupt.");
return;
}
}
private void signBtn_Click(object sender, EventArgs e)
{
if (string.IsNullOrWhiteSpace(FilePath))
{
MessageBox.Show("Error: Choose a file.");
return;
}
try
{
var signTuple = dsa.SignData(MessageBytes);
// save signature to file
File.WriteAllText(FilePath.Substring(0, FilePath.IndexOf('.')) + "_Sign.txt", DsaSerializer.Serialize(signTuple));
MessageBox.Show("File was signed successfully.");
}
catch (Exception ex)
{
MessageBox.Show($"Error: {ex.Message}");
}
}