public bool Decode(byte[] data, string password)
{
var msEncoded = new MemoryStream(data);
byte[] buffer = new byte[4];
msEncoded.Read(buffer, 0, 4);
int encodedBytes = BitConverter.ToInt32(buffer, 0);
buffer = new byte[encodedBytes];
msEncoded.Read(buffer, 0, buffer.Length);
byte[] decodedBytes = EncryptionManager.DecryptData(buffer, password);
msEncoded.Read(buffer, 0, 4);
int hashByteLength = BitConverter.ToInt32(buffer, 0);
if (hashByteLength > 512)
{
return(false);
}
byte[] hashBytesFromData = new byte[hashByteLength];
msEncoded.Read(hashBytesFromData, 0, hashBytesFromData.Length);
byte[] hashBytesFromDecodedDataBytes = SHA512.Create().ComputeHash(decodedBytes, 0, decodedBytes.Length);
bool hashCompareResult = GeneralConverters.ByteArrayToBase64(hashBytesFromData) == GeneralConverters.ByteArrayToBase64(hashBytesFromDecodedDataBytes);
if (!hashCompareResult)
{
return(false);
}
var msDecoded = new MemoryStream(decodedBytes);
buffer = new byte[4];
msDecoded.Read(buffer, 0, buffer.Length);
int leftPaddingLength = BitConverter.ToInt32(buffer, 0);
msDecoded.Read(buffer, 0, buffer.Length);
int rightPaddingLength = BitConverter.ToInt32(buffer, 0);
msDecoded.Read(buffer, 0, buffer.Length);
int totalLength = BitConverter.ToInt32(buffer, 0);
byte[] decodedDataBlock = new byte[totalLength];
msDecoded.Read(decodedDataBlock, 0, decodedDataBlock.Length);
byte[] sharedSecretBytes = new byte[totalLength - leftPaddingLength - rightPaddingLength];
Buffer.BlockCopy(decodedDataBlock, leftPaddingLength, sharedSecretBytes, 0, sharedSecretBytes.Length);
SharedSecret = GeneralConverters.GetStringFromByteArray(sharedSecretBytes);
return(true);
}
