예제 #1
0
 private static void DecryptFile(string filePath, int parametersLength, byte[] macBackup, byte[] encryptionKey, BackgroundWorker bgwDecryption)
 {
     try
     {
         string decryptedFilePath = Regex.Replace(filePath, Constants.EncryptedExtension, string.Empty);
         int    headersLength     = Constants.SaltLength + parametersLength;
         using (var plaintext = new FileStream(decryptedFilePath, FileMode.Create, FileAccess.ReadWrite, FileShare.Read, Constants.FileBufferSize, FileOptions.SequentialScan))
             using (var ciphertext = new FileStream(filePath, FileMode.Open, FileAccess.ReadWrite, FileShare.Read, Constants.FileBufferSize, FileOptions.SequentialScan))
             {
                 // Skip the header bytes
                 ciphertext.Seek(headersLength, SeekOrigin.Begin);
                 byte[] fileBytes = FileHandling.GetBufferSize(ciphertext.Length);
                 // Generate a counter starting at 0
                 byte[] counter = Generate.Counter();
                 int    bytesRead;
                 MemoryEncryption.DecryptByteArray(ref encryptionKey);
                 while ((bytesRead = ciphertext.Read(fileBytes, 0, fileBytes.Length)) > 0)
                 {
                     byte[] decryptedBytes = StreamEncryption.DecryptXChaCha20(fileBytes, counter, encryptionKey);
                     plaintext.Write(decryptedBytes, 0, bytesRead);
                     counter = Sodium.Utilities.Increment(counter);
                     // Report progress if decrypting a single file
                     ReportProgress.ReportEncryptionProgress(plaintext.Position, ciphertext.Length, bgwDecryption);
                 }
                 Utilities.ZeroArray(encryptionKey);
             }
         CompleteDecryption(filePath, decryptedFilePath);
     }
     catch (Exception ex) when(ExceptionFilters.FileEncryptionExceptions(ex))
     {
         Logging.LogException(ex.ToString(), Logging.Severity.High);
         DisplayMessage.ErrorResultsText(filePath, ex.GetType().Name, "Failed to backup the MAC. This data is required for decryption.");
         Utilities.ZeroArray(encryptionKey);
         RestoreMAC(filePath, macBackup);
     }
 }
예제 #2
0
 private static void EncryptFile(string filePath, string encryptedFilePath, byte[] salt, byte[] encryptionKey, byte[] macKey, BackgroundWorker bgwEncryption)
 {
     try
     {
         using (var ciphertext = new FileStream(encryptedFilePath, FileMode.Create, FileAccess.ReadWrite, FileShare.Read, Constants.FileBufferSize, FileOptions.SequentialScan))
             using (var plaintext = new FileStream(filePath, FileMode.Open, FileAccess.ReadWrite, FileShare.Read, Constants.FileBufferSize, FileOptions.SequentialScan))
             {
                 WriteFileHeaders.WriteHeaders(ciphertext, salt);
                 // Store headers length to correct percentage calculation
                 long   headersLength = ciphertext.Position;
                 byte[] fileBytes     = FileHandling.GetBufferSize(plaintext.Length);
                 // Generate a counter starting at 0
                 byte[] counter = Generate.Counter();
                 int    bytesRead;
                 MemoryEncryption.DecryptByteArray(ref encryptionKey);
                 while ((bytesRead = plaintext.Read(fileBytes, 0, fileBytes.Length)) > 0)
                 {
                     byte[] encryptedBytes = StreamEncryption.EncryptXChaCha20(fileBytes, counter, encryptionKey);
                     ciphertext.Write(encryptedBytes, 0, bytesRead);
                     counter = Sodium.Utilities.Increment(counter);
                     // Report progress if encrypting a single file
                     ReportProgress.ReportEncryptionProgress(ciphertext.Position, plaintext.Length + headersLength, bgwEncryption);
                 }
             }
         Utilities.ZeroArray(encryptionKey);
         CompleteEncryption(filePath, encryptedFilePath, macKey);
     }
     catch (Exception ex) when(ExceptionFilters.FileEncryptionExceptions(ex))
     {
         Logging.LogException(ex.ToString(), Logging.Severity.High);
         DisplayMessage.ErrorResultsText(filePath, ex.GetType().Name, "Unable to encrypt the file.");
         FileHandling.DeleteFile(encryptedFilePath);
         Utilities.ZeroArray(encryptionKey);
         Utilities.ZeroArray(macKey);
     }
 }