private int GenerateInternal(byte b, byte[] salt, ref bool isSaltEncrypted, bool doNotEncrypt = false)
{
var byteBuffer = new byte[salt.Length + 1];
try
{
//Decrypt salt
if (isSaltEncrypted)
{
_memoryProtector.Unprotect(salt);
isSaltEncrypted = false;
}
//Append salt + byte
Array.Copy(salt, byteBuffer, salt.Length);
byteBuffer[salt.Length] = b;
//Hash it
var result = _fastHasher.ComputeFast(byteBuffer);
return(result);
}
finally
{
Array.Clear(byteBuffer, 0, byteBuffer.Length);
//Encrypt the salt
if (!isSaltEncrypted && !doNotEncrypt)
{
_memoryProtector.Protect(salt);
isSaltEncrypted = true;
}
}
}
/// <summary>
/// Appends the specified <see cref="ISafeByte" /> instance to the inner encrypted collection.
/// </summary>
/// <param name="safeByte">The safe byte.</param>
/// <exception cref="System.ArgumentNullException"><paramref name="safeByte" /> is <see langword="null" />.</exception>
/// <exception cref="ObjectDisposedException">Throws if the <see cref="EncryptedSafeByteCollection" /> instance is disposed</exception>
/// <seealso cref="ISafeByte" />
public void Append(ISafeByte safeByte)
{
EnsureNotDisposed();
if (safeByte == null)
{
throw new ArgumentNullException(nameof(safeByte));
}
_memoryProtector.Unprotect(_encryptionKey);
var list = DecryptAndDeserialize(_encryptedCollection, _encryptionKey);
list.Add(safeByte.Id);
_encryptedCollection = SerializeAndEncrypt(list, _encryptionKey);
list.Clear();
_memoryProtector.Protect(_encryptionKey);
Length++;
}
/// <summary>
/// Private constructor for creating identical instance of the <see cref="SafeByte" />.
/// </summary>
private SafeByte(
int id, int realBytePosition,
int encryptedByteLength, byte[] encryptionKey, byte[] encryptedByte,
IFastEncryptor encryptor,
IFastRandom fastRandom,
IByteIdGenerator byteIdGenerator,
IByteArrayProtector memoryProtector)
{
_encryptor = encryptor;
_fastRandom = fastRandom;
_byteIdGenerator = byteIdGenerator;
_memoryProtector = memoryProtector;
//Deep copy
_id = id;
_realBytePosition = realBytePosition;
_encryptedByte = new byte[encryptedByte.Length];
_encryptionKey = new byte[encryptionKey.Length];
Buffer.BlockCopy(encryptedByte, 0, _encryptedByte, 0, encryptedByte.Length);
Buffer.BlockCopy(encryptionKey, 0, _encryptionKey, 0, encryptionKey.Length);
_memoryProtector.Protect(_encryptionKey);
_memoryProtector.Protect(_encryptedByte);
_encryptedByteLength = encryptedByteLength;
IsByteSet = true;
}
internal EncryptedSafeByteCollection(IFastEncryptor encryptor, IByteArrayProtector memoryProtector,
IFastRandom fastRandom, ISafeByteFactory safeByteFactory)
{
if (encryptor == null)
{
throw new ArgumentNullException(nameof(encryptor));
}
if (memoryProtector == null)
{
throw new ArgumentNullException(nameof(memoryProtector));
}
if (safeByteFactory == null)
{
throw new ArgumentNullException(nameof(safeByteFactory));
}
_encryptor = encryptor;
_memoryProtector = memoryProtector;
_safeByteFactory = safeByteFactory;
_encryptionKey = fastRandom.GetBytes(_memoryProtector.BlockSizeInBytes);
_memoryProtector.Protect(_encryptionKey);
}
/// <exception cref="System.InvalidOperationException">Thrown when byte is already set</exception>
public void Set(byte b)
{
EnsureByteIsNotSet();
RuntimeHelper.ExecuteCodeWithGuaranteedCleanup(
() =>
{
//Generate ID
_id = _byteIdGenerator.Generate(b);
//Encrypt
Encrypt(b);
IsByteSet = true;
},
() =>
{
_memoryProtector.Protect(_encryptionKey);
_memoryProtector.Protect(_encryptedByte);
});
}
