public UserAccount()
{
CngKeyCreationParameters keyCreationParameters = new CngKeyCreationParameters();
keyCreationParameters.ExportPolicy = CngExportPolicies.AllowPlaintextExport;
keyCreationParameters.KeyUsage = CngKeyUsages.Signing;
CngKey key = CngKey.Create(CngAlgorithm.ECDsaP256, null, keyCreationParameters);
ECDsaCng dsa = new ECDsaCng(key); //dsa = Digital Signature Algorithm
byte[] privateKey = dsa.Key.Export(CngKeyBlobFormat.EccPrivateBlob);
ECDSAPrivateKey = BitConverter.ToString(privateKey).Replace("-", String.Empty);
//create public key
byte[] publicKey = dsa.Key.Export(CngKeyBlobFormat.EccPublicBlob);
ECSDAPublicKey = BitConverter.ToString(publicKey).Replace("-", String.Empty);
//we calculate the hashvalue by slicing the end off of the public key
string hashValue = ECDSAOperations.GetHashValue(publicKey);
int hashLength = hashValue.Length;
UserAddress = "0x" + hashValue.Substring(hashLength - ADDRESS_LENGTH);
}
private void btnVerify_Click(object sender, EventArgs e)
{
string signature = txtMAC.Text;
string publicKey = txtPublicKey.Text;
string hashValue = txtHash.Text;
bool verify = ECDSAOperations.VerifySignature(hashValue, signature, publicKey);
}
private void btnSign_Click(object sender, EventArgs e)
{
string fileHash = ECDSAOperations.GetSha256FileHash(txtFileURL.Text);
if (fileHash.Length > 0)
{
txtHash.Text = fileHash;
string signature = ECDSAOperations.SignMessage(txtPrivateKey.Text, fileHash);
txtMAC.Text = signature;
}
}