示例#1
0
 public static void Initialize(string inputFilePath, string outputFilePath, byte[] keyEncryptionKey)
 {
     byte[] dataEncryptionKey = new byte[Constants.EncryptionKeyLength];
     try
     {
         byte[] encryptedHeader = FileHeaders.ReadEncryptedHeader(inputFilePath);
         byte[] nonce           = FileHeaders.ReadNonce(inputFilePath);
         byte[] header          = DecryptFileHeader(inputFilePath, encryptedHeader, nonce, keyEncryptionKey);
         if (header == null)
         {
             throw new ArgumentException("Incorrect password/keyfile or this file has been tampered with.");
         }
         ChunkHandling.ValidateKeyCommitmentBlock(header);
         int lastChunkLength = FileHeaders.GetLastChunkLength(header);
         int fileNameLength  = FileHeaders.GetFileNameLength(header);
         dataEncryptionKey = FileHeaders.GetDataEncryptionKey(header);
         Utilities.ZeroArray(header);
         using (var inputFile = new FileStream(inputFilePath, FileMode.Open, FileAccess.Read, FileShare.Read, Constants.FileStreamBufferSize, FileOptions.SequentialScan))
             using (var outputFile = new FileStream(outputFilePath, FileMode.Create, FileAccess.ReadWrite, FileShare.Read, Constants.FileStreamBufferSize, FileOptions.SequentialScan))
             {
                 nonce = Sodium.Utilities.Increment(nonce);
                 byte[] additionalData = ChunkHandling.GetPreviousPoly1305Tag(encryptedHeader);
                 Decrypt(inputFile, outputFile, nonce, dataEncryptionKey, additionalData, lastChunkLength);
             }
         Finalize(inputFilePath, outputFilePath, fileNameLength);
     }
     catch (Exception ex) when(ExceptionFilters.Cryptography(ex))
     {
         Utilities.ZeroArray(dataEncryptionKey);
         throw;
     }
 }
示例#2
0
        private static byte[] EncryptFileHeader(string inputFilePath, byte[] ephemeralPublicKey, byte[] dataEncryptionKey, byte[] nonce, byte[] keyEncryptionKey)
        {
            long fileLength = FileHandling.GetFileLength(inputFilePath);

            byte[] lastChunkLength = BitConversion.GetBytes(Convert.ToInt32(fileLength % Constants.FileChunkSize));
            byte[] fileNameLength  = FileHeaders.GetFileNameLength(inputFilePath);
            byte[] fileHeader      = Arrays.Concat(lastChunkLength, fileNameLength, dataEncryptionKey);
            byte[] additionalData  = HeaderEncryption.ComputeAdditionalData(fileLength, ephemeralPublicKey);
            return(HeaderEncryption.Encrypt(fileHeader, nonce, keyEncryptionKey, additionalData));
        }
示例#3
0
        private static byte[] EncryptFileHeader(string inputFilePath, byte[] dataEncryptionKey, byte[] nonce, byte[] keyEncryptionKey)
        {
            byte[] keyCommitmentBlock = ChunkHandling.GetKeyCommitmentBlock();
            long   fileLength         = FileHandling.GetFileLength(inputFilePath);

            byte[] lastChunkLength = BitConverter.GetBytes(Convert.ToInt32(fileLength % Constants.FileChunkSize));
            byte[] fileNameLength  = FileHeaders.GetFileNameLength(inputFilePath);
            byte[] fileHeader      = Utilities.ConcatArrays(keyCommitmentBlock, lastChunkLength, fileNameLength, dataEncryptionKey);
            byte[] additionalData  = HeaderEncryption.ComputeAdditionalData(fileLength);
            return(HeaderEncryption.Encrypt(fileHeader, nonce, keyEncryptionKey, additionalData));
        }
示例#4
0
        public static void Initialize(FileStream inputFile, string outputFilePath, byte[] ephemeralPublicKey, byte[] keyEncryptionKey)
        {
            var dataEncryptionKey = new byte[Constants.EncryptionKeyLength];

            try
            {
                byte[] encryptedHeader = FileHeaders.ReadEncryptedHeader(inputFile);
                byte[] nonce           = FileHeaders.ReadNonce(inputFile);
                byte[] header          = DecryptFileHeader(inputFile, ephemeralPublicKey, encryptedHeader, nonce, keyEncryptionKey);
                if (header == null)
                {
                    throw new ArgumentException("Incorrect password/key or this file has been tampered with.");
                }
                int lastChunkLength = FileHeaders.GetLastChunkLength(header);
                int fileNameLength  = FileHeaders.GetFileNameLength(header);
                dataEncryptionKey = FileHeaders.GetDataEncryptionKey(header);
                CryptographicOperations.ZeroMemory(header);
                using (var outputFile = new FileStream(outputFilePath, FileMode.Create, FileAccess.ReadWrite, FileShare.Read, Constants.FileStreamBufferSize, FileOptions.SequentialScan))
                {
                    nonce = Utilities.Increment(nonce);
                    byte[] additionalData = ChunkHandling.GetPreviousTag(encryptedHeader);
                    Decrypt(inputFile, outputFile, nonce, dataEncryptionKey, additionalData, lastChunkLength);
                }
                string inputFilePath = inputFile.Name;
                inputFile.Dispose();
                Finalize(inputFilePath, outputFilePath, fileNameLength);
            }
            catch (Exception ex) when(ExceptionFilters.Cryptography(ex))
            {
                CryptographicOperations.ZeroMemory(dataEncryptionKey);
                if (!(ex is ArgumentException))
                {
                    FileHandling.DeleteFile(outputFilePath);
                }
                throw;
            }
        }