public static byte[] Encrypt(byte[] passwordBytes, byte[] keyAlgorithm, byte[] privateKey)
{
byte[] salt = Generate.Salt();
byte[] key = Argon2.DeriveKey(passwordBytes, salt);
CryptographicOperations.ZeroMemory(passwordBytes);
byte[] nonce = Generate.Nonce();
byte[] additionalData = Arrays.Concat(keyAlgorithm, Constants.PrivateKeyVersion);
byte[] encryptedPrivateKey = XChaCha20BLAKE2b.Encrypt(privateKey, nonce, key, additionalData, TagLength.Medium);
CryptographicOperations.ZeroMemory(privateKey);
CryptographicOperations.ZeroMemory(key);
return(Arrays.Concat(additionalData, salt, nonce, encryptedPrivateKey));
}
private static void Encrypt(FileStream inputFile, FileStream outputFile, byte[] nonce, byte[] dataEncryptionKey, byte[] additionalData)
{
const int offset = 0;
byte[] plaintextChunk = new byte[Constants.FileChunkSize];
while (inputFile.Read(plaintextChunk, offset, plaintextChunk.Length) > 0)
{
byte[] ciphertextChunk = XChaCha20BLAKE2b.Encrypt(plaintextChunk, nonce, dataEncryptionKey, additionalData, TagLength.Medium);
nonce = Utilities.Increment(nonce);
additionalData = ChunkHandling.GetPreviousTag(ciphertextChunk);
outputFile.Write(ciphertextChunk, offset, ciphertextChunk.Length);
}
CryptographicOperations.ZeroMemory(dataEncryptionKey);
}
public static byte[] Encrypt(byte[] fileHeader, byte[] nonce, byte[] keyEncryptionKey, byte[] additionalData)
{
return(XChaCha20BLAKE2b.Encrypt(fileHeader, nonce, keyEncryptionKey, additionalData, TagLength.Medium));
}