/// <summary>
/// Signs the specified data using Private key.
/// </summary>
public override byte[] Sign(byte[] data, IPrivateKey privateKey)
{
if (data == null)
{
throw new ArgumentNullException(nameof(data));
}
if (privateKey == null)
{
throw new ArgumentNullException(nameof(privateKey));
}
try
{
using (var signer = new VirgilSigner())
{
var signature = signer.Sign(data, privateKey.Get().Value);
return(signature);
}
}
catch (Exception ex)
{
throw new CryptoException(ex.Message);
}
}
/// <summary>
/// Signs and encrypts the data.
/// </summary>
/// <param name="data">The data to encrypt.</param>
/// <param name="privateKey">The Private key to sign the <param name="data"></param>.</param>
/// <param name="recipients">The list of Public key recipients to encrypt the <param name="data"></param>.</param>
/// <returns></returns>
/// <exception cref="Virgil.SDK.Exceptions.CryptoException"></exception>
public override byte[] SignThenEncrypt(byte[] data, IPrivateKey privateKey, params IPublicKey[] recipients)
{
try
{
using (var signer = new VirgilSigner())
using (var cipher = new VirgilCipher())
{
var signature = signer.Sign(data, privateKey.Get().Value);
var customData = cipher.CustomParams();
customData.SetData(this.CustomParamKeySignature, signature);
foreach (var publicKey in recipients)
{
cipher.AddKeyRecipient(publicKey.Get().ReceiverId, publicKey.Get().Value);
}
return(cipher.Encrypt(data, true));
}
}
catch (Exception ex)
{
throw new CryptoException(ex.Message);
}
}
/// <summary>
/// Decrypts and verifies the data.
/// </summary>
/// <param name="cipherData">The cipher data.</param>
/// <param name="privateKey">The Private key to decrypt.</param>
/// <param name="publicKeys"> The list of trusted public keys for verification,
/// which can contain signer's public key.</param>
/// <returns>The decrypted data</returns>
/// <exception cref="Virgil.SDK.Exceptions.SignatureIsNotValidException"></exception>
/// <exception cref="Virgil.SDK.Exceptions.CryptoException"></exception>
/// <example>
/// <code>
/// var crypto = new VirgilCrypto();
/// var decryptedData = crypto.DecryptThenVerify(cipherData, bob.PrivateKey, alice.PublicKey);
/// </code>
/// </example>
/// How to get cipherData as well as Alice's and Bob's key pairs.
/// <see cref="SignThenEncrypt(byte[] data, IPrivateKey privateKey, params IPublicKey[] recipients)"/>
public override byte[] DecryptThenVerify(byte[] cipherData, IPrivateKey privateKey, params IPublicKey[] publicKeys)
{
try
{
using (var signer = new VirgilSigner())
using (var cipher = new VirgilCipher())
{
var decryptedData = cipher.DecryptWithKey(cipherData, privateKey.Get().ReceiverId, privateKey.Get().Value);
var signature = cipher.CustomParams().GetData(this.CustomParamKeySignature);
var signerPublicKey = publicKeys.FirstOrDefault();
if (publicKeys.Length > 1)
{
var signerId = cipher.CustomParams().GetData(this.CustomParamKeySignerId);
signerPublicKey = publicKeys.Single(publicKey => publicKey.Get().ReceiverId.SequenceEqual(signerId));
}
var isValid = signer.Verify(decryptedData, signature, signerPublicKey.Get().Value);
if (!isValid)
{
throw new SignatureIsNotValidException();
}
return(decryptedData);
}
}
catch (Exception ex)
{
throw new CryptoException(ex.Message);
}
}
/// <summary>
/// Extracts the Public key from Private key.
/// </summary>
public override IPublicKey ExtractPublicKey(IPrivateKey privateKey)
{
try
{
var publicKeyData = VirgilKeyPair.ExtractPublicKey(privateKey.Get().Value, new byte[] { });
var publicKey = new PublicKey
{
ReceiverId = privateKey.Get().ReceiverId,
Value = VirgilKeyPair.PublicKeyToDER(publicKeyData)
};
return(publicKey);
}
catch (Exception ex)
{
throw new CryptoException(ex.Message);
}
}
/// <summary>
/// Exports the Private key into material representation.
/// </summary>
public override byte[] ExportPrivateKey(IPrivateKey privateKey, string password = null)
{
try
{
if (string.IsNullOrEmpty(password))
{
return(VirgilKeyPair.PrivateKeyToDER(privateKey.Get().Value));
}
var passwordBytes = Encoding.UTF8.GetBytes(password);
var encryptedKey = VirgilKeyPair.EncryptPrivateKey(privateKey.Get().Value, passwordBytes);
return(VirgilKeyPair.PrivateKeyToDER(encryptedKey, passwordBytes));
}
catch (Exception ex)
{
throw new CryptoException(ex.Message);
}
}
/// <summary>
/// Decrypts the specified data using Private key.
/// </summary>
public override byte[] Decrypt(byte[] cipherData, IPrivateKey privateKey)
{
try
{
using (var cipher = new VirgilCipher())
{
var data = cipher.DecryptWithKey(cipherData, privateKey.Get().ReceiverId, privateKey.Get().Value);
return(data);
}
}
catch (Exception ex)
{
throw new CryptoException(ex.Message);
}
}
/// <summary>
/// Signs the specified stream using Private key.
/// </summary>
public override byte[] Sign(Stream inputStream, IPrivateKey privateKey)
{
try
{
using (var signer = new VirgilStreamSigner())
using (var source = new VirgilStreamDataSource(inputStream))
{
var signature = signer.Sign(source, privateKey.Get().Value);
return(signature);
}
}
catch (Exception ex)
{
throw new CryptoException(ex.Message);
}
}
/// <summary>
/// Decrypts the specified stream using Private key.
/// </summary>
public override void Decrypt(Stream cipherStream, Stream outputStream, IPrivateKey privateKey)
{
try
{
using (var cipher = new VirgilChunkCipher())
using (var source = new VirgilStreamDataSource(cipherStream))
using (var sink = new VirgilStreamDataSink(outputStream))
{
cipher.DecryptWithKey(source, sink, privateKey.Get().ReceiverId, privateKey.Get().Value);
}
}
catch (Exception ex)
{
throw new CryptoException(ex.Message);
}
}
/// <summary>
/// Decrypts and verifies the data.
/// </summary>
/// <param name="cipherData">The cipher data.</param>
/// <param name="privateKey">The Private key to decrypt.</param>
/// <param name="publicKey">The Public key to verify.</param>
/// <returns>The decrypted data</returns>
/// <exception cref="Virgil.SDK.Exceptions.SignatureIsNotValidException"></exception>
/// <exception cref="Virgil.SDK.Exceptions.CryptoException"></exception>
public override byte[] DecryptThenVerify(byte[] cipherData, IPrivateKey privateKey, IPublicKey publicKey)
{
try
{
using (var signer = new VirgilSigner())
using (var cipher = new VirgilCipher())
{
var decryptedData = cipher.DecryptWithKey(cipherData, privateKey.Get().ReceiverId, privateKey.Get().Value);
var signature = cipher.CustomParams().GetData(this.CustomParamKeySignature);
var isValid = signer.Verify(decryptedData, signature, publicKey.Get().Value);
if (!isValid)
{
throw new SignatureIsNotValidException();
}
return(decryptedData);
}
}
catch (Exception ex)
{
throw new CryptoException(ex.Message);
}
}