public override IList <byte[]> Encrypt(byte[] binaryData, AesKey usingKey)
{
return(new List <byte[]>()
{
EncryptionAlgo.Encrypt(binaryData, usingKey)
});
}
public override IList <byte[]> Encrypt(byte[] binaryData, RsaKey usingKey)
{
// Get maximum bytes allowed and encrypt segments of binaryData based on this
// Refactor if you have the restriction with other encryption algorithms
var maxBytestoEncrypt = _maxEncryptionCalc.GetMaxBytesThatCanBeEncrypted(usingKey);
var ret = new List <byte[]>((int)Math.Max(1, Math.Ceiling((double)binaryData.Length / maxBytestoEncrypt)));
for (int i = 0; i < binaryData.Length; i = i + maxBytestoEncrypt)
{
var currSegmentSize = Math.Min(binaryData.Length - i, maxBytestoEncrypt);
var segmentToEncrypt = new byte[currSegmentSize];
Buffer.BlockCopy(binaryData, i, segmentToEncrypt, 0, currSegmentSize);
ret.Add(EncryptionAlgo.Encrypt(segmentToEncrypt, usingKey));
}
return(ret);
}
/// <summary>
/// Creates a new instance of the <see cref="SecuritySettings"/> class.
/// </summary>
/// <param name="encryptionAlgo">The algorithm used to encrypt data in the archive.</param>
/// <param name="keyDerivationFunction">The key derivation function (KDF) used to generate user keys.</param>
/// <param name="keyDerivationWorkFactor">The work factor parameter (e.g. iteration count) for the KDF.</param>
/// <param name="KeyIdSizeInBytes">The size (in bytes) of KeyIds generated for user keys.</param>
public static SecuritySettings Create(
EncryptionAlgo encryptionAlgo,
KeyDerivationFunction keyDerivationFunction,
int keyDerivationWorkFactor,
int keyIdSizeInBytes)
{
ArgCheck.IsNot(EncryptionAlgo.Unknown, encryptionAlgo, nameof(encryptionAlgo));
ArgCheck.IsNot(KeyDerivationFunction.Unknown, keyDerivationFunction, nameof(keyDerivationFunction));
ArgCheck.GreaterThanZero(keyDerivationWorkFactor, nameof(keyDerivationWorkFactor));
ArgCheck.GreaterThanZero(keyIdSizeInBytes, nameof(keyIdSizeInBytes));
return(new SecuritySettings
{
EncryptionAlgo = encryptionAlgo,
KeyDerivationFunction = keyDerivationFunction,
KeyDerivationWorkFactor = keyDerivationWorkFactor,
KeyIdSizeInBytes = keyIdSizeInBytes,
});
}
/// <summary>
/// Reads a pure binary form <see cref="EncryptedPacket"/> from the given stream.
/// </summary>
/// <param name="stream">The stream to read from.</param>
/// <param name="encryptionAlgo">The algo used to create the encrypted packet.</param>
/// <returns>The <see cref="EncryptedPacket"/> read from the stream.</returns>
public static EncryptedPacket ReadFromBinaryStream(Stream stream, EncryptionAlgo encryptionAlgo)
{
byte[] iv = null;
byte[] authTag = null;
byte[] cipherText = null;
var encryptionAlgoProperties = EncryptionAlgoProperties.For(encryptionAlgo);
if (encryptionAlgoProperties.IvSizeInBytes > 0)
{
iv = new byte[encryptionAlgoProperties.IvSizeInBytes];
var ivBytesRead = stream.Read(iv, 0, encryptionAlgoProperties.IvSizeInBytes);
Debug.Assert(ivBytesRead == encryptionAlgoProperties.IvSizeInBytes);
}
if (encryptionAlgoProperties.IsAuthenticated && encryptionAlgoProperties.AuthTagSizeInBytes > 0)
{
authTag = new byte[encryptionAlgoProperties.AuthTagSizeInBytes];
var authTagBytesRead = stream.Read(authTag);
Debug.Assert(authTagBytesRead == encryptionAlgoProperties.AuthTagSizeInBytes);
}
var cipherTextSizeInBytes = stream.Length - stream.Position;
if (cipherTextSizeInBytes > 0)
{
cipherText = new byte[cipherTextSizeInBytes];
var cipherTextBytesRead = stream.Read(cipherText);
Debug.Assert(cipherTextBytesRead == cipherTextSizeInBytes);
}
return(CreateNewEncryptedPacket(cipherText, iv, authTag));
}
/// <summary>
/// Gets the <see cref="ICryptoStrategy"/> associated with the given cryptographic algorithm.
/// </summary>
/// <param name="algo">The cryptographic algorithm.</param>
/// <returns>The <see cref="ICryptoStrategy"/> associated with the algorithm.</returns>
public static ICryptoStrategy GetCryptoStrategy(EncryptionAlgo algo) => algo switch
{
/// <summary>
/// Gets the <see cref="EncryptionAlgoProperties"/> for a given <see cref="EncryptionAlgo"/>.
/// </summary>
/// <param name="algo">The <see cref="EncryptionAlgo"/> to get properties for.</param>
/// <returns>The <see cref="EncryptionAlgoProperties"/>.</returns>
public static EncryptionAlgoProperties For(EncryptionAlgo algo) => algo switch
{
