/// <summary>
/// Verifies a signature to be authentic
/// </summary>
/// <param name="originalSignature">The signature which is be verified</param>
/// <param name="publicKey">the public key used for the verification</param>
/// <param name="data">the data which is signed</param>
/// <returns>true if signature is authentic, false if not</returns>
public bool Verify(byte[] originalSignature, byte[] publicKey, byte[] data)
{
Ed448PublicKeyParameters pubKey = null;
try
{
pubKey = (Ed448PublicKeyParameters)CreateAsymmetricKeyParameterFromPublicKeyInfo(publicKey);
}
catch (InvalidCastException exception)
{
string message = "Public Key Import Failed!\n" +
$"{exception.Message}.\n" +
"The contents of the source do not represent a valid Ed448 key parameter\n" +
"Verify that the key is not corrupted.\n" +
"- or - Verify that the correct key is selected.";
throw new CryptoException(message, exception);
}
var signer = new Ed448Signer(ByteConvert.StringToAsciiBytes("context"));
signer.Init(false, pubKey);
signer.BlockUpdate(data, 0, data.Length);
return(signer.VerifySignature(originalSignature));
}
/// <summary>
/// Signs the passed in data with a private key
/// </summary>
/// <param name="privateKey">the private key used to create the signature</param>
/// <param name="data">The data to sign</param>
/// <returns>the signature as a byte array</returns>
public byte[] Sign(byte[] privateKey, byte[] data)
{
var signer = new Ed448Signer(ByteConvert.StringToAsciiBytes("context"));
Ed448PrivateKeyParameters privKey = null;
try
{
privKey = (Ed448PrivateKeyParameters)CreateAsymmetricKeyParameterFromPrivateKeyInfo(privateKey);
}
catch (InvalidCastException exception)
{
string message = "Private Key Import Failed!\n" +
$"{exception.Message}.\n" +
"The contents of the source do not represent a valid Ed448 key parameter\n" +
"Verify that the key is not corrupted.\n" +
"- or - Verify that the correct key is selected.";
throw new CryptoException(message, exception);
}
signer.Init(true, privKey);
signer.BlockUpdate(data, 0, data.Length);
var signature = signer.GenerateSignature();
return(signature);
}
/// <summary>
/// Encrypts a plain text using a public key
/// </summary>
/// <param name="publicKey">the key used for encryption</param>
/// <param name="plainText">the plain text to encrypt</param>
/// <returns>encrypted bytes</returns>
public byte[] EncryptText(byte[] publicKey, string plainText)
{
var plain = ByteConvert.StringToAsciiBytes(plainText);
return(EncryptBytes(publicKey, plain));
}
