private static void CallEncryption(bool encryption, string filePath, byte[] passwordBytes, ref int progress, BackgroundWorker backgroundWorker)
{
try
{
bool kryptorExtension = filePath.EndsWith(Constants.EncryptedExtension, StringComparison.Ordinal);
// Prevent Read-Only file attribute causing errors
File.SetAttributes(filePath, FileAttributes.Normal);
if (encryption == true && kryptorExtension == false)
{
Encryption.InitializeEncryption(filePath, passwordBytes, backgroundWorker);
OverwriteDisabled(filePath);
}
else if (encryption == false && kryptorExtension == true)
{
Decryption.InitializeDecryption(filePath, passwordBytes, backgroundWorker);
}
else
{
DisplayFileError(filePath, encryption, kryptorExtension);
}
ReportProgress.IncrementProgress(ref progress, backgroundWorker);
}
catch (Exception ex) when(ExceptionFilters.FileAccessExceptions(ex))
{
Logging.LogException(ex.ToString(), Logging.Severity.High);
DisplayMessage.ErrorResultsText(filePath, ex.GetType().Name, "Unable to set file attributes to normal.");
}
}
public static void Decrypt(FileStream plaintext, FileStream ciphertext, byte[] fileBytes, byte[] nonce, byte[] key, BackgroundWorker bgwDecryption)
{
NullChecks.FileEncryption(plaintext, ciphertext, fileBytes, nonce, key);
int bytesRead;
while ((bytesRead = ciphertext.Read(fileBytes, 0, fileBytes.Length)) > 0)
{
byte[] decryptedBytes = DecryptFileBytes(fileBytes, nonce, key);
plaintext.Write(decryptedBytes, 0, bytesRead);
// Report progress if decrypting a single file
ReportProgress.ReportEncryptionProgress(plaintext.Position, ciphertext.Length, bgwDecryption);
}
}
public static void DecryptAesCBC(FileStream plaintext, FileStream ciphertext, byte[] fileBytes, byte[] nonce, byte[] key, BackgroundWorker bgwDecryption)
{
NullChecks.FileEncryption(plaintext, ciphertext, fileBytes, nonce, key);
using (var aes = new AesCryptoServiceProvider()
{
Mode = _cbcMode, Padding = _pkcs7Padding
})
{
using (var cryptoStream = new CryptoStream(ciphertext, aes.CreateDecryptor(key, nonce), CryptoStreamMode.Read))
{
int bytesRead;
while ((bytesRead = cryptoStream.Read(fileBytes, 0, fileBytes.Length)) > 0)
{
plaintext.Write(fileBytes, 0, bytesRead);
// Report progress if encrypting a single file
ReportProgress.ReportEncryptionProgress(plaintext.Position, ciphertext.Length, bgwDecryption);
}
}
}
}
private static void CallShredFilesMethod(string filePath, ref int progress, BackgroundWorker bgwShredFiles)
{
try
{
File.SetAttributes(filePath, FileAttributes.Normal);
switch (Globals.ShredFilesMethod)
{
case 0:
ShredFilesMethods.FirstLast16KiB(filePath);
break;
case 1:
// false = use zeros, not ones (used in Infosec Standard 5 Enhanced)
ShredFilesMethods.ZeroFill(filePath, false, bgwShredFiles);
break;
case 2:
ShredFilesMethods.PseudorandomData(filePath, bgwShredFiles);
break;
case 3:
ShredFilesMethods.EncryptionErasure(filePath, bgwShredFiles);
break;
case 4:
ShredFilesMethods.InfosecStandard5Enhanced(filePath, bgwShredFiles);
break;
case 5:
ShredFilesMethods.PseudorandomData5Passes(filePath, bgwShredFiles);
break;
}
DeleteFile(filePath);
ReportProgress.IncrementProgress(ref progress, bgwShredFiles);
}
catch (Exception ex) when(ExceptionFilters.FileAccessExceptions(ex))
{
Logging.LogException(ex.ToString(), Logging.Severity.High);
DisplayMessage.ErrorResultsText(filePath, ex.GetType().Name, "Unable to set file attributes to normal. This file has not been shredded.");
}
}
public static void PseudorandomData(string filePath, BackgroundWorker bgwShredFiles)
{
try
{
using (var fileStream = new FileStream(filePath, FileMode.Open, FileAccess.ReadWrite, FileShare.Read))
{
byte[] randomBytes = FileHandling.GetBufferSize(fileStream);
while (fileStream.Position < fileStream.Length)
{
randomBytes = SodiumCore.GetRandomBytes(randomBytes.Length);
fileStream.Write(randomBytes, 0, randomBytes.Length);
ReportProgress.ReportEncryptionProgress(fileStream.Position, fileStream.Length, bgwShredFiles);
}
}
}
catch (Exception ex) when(ExceptionFilters.FileAccessExceptions(ex))
{
Logging.LogException(ex.ToString(), Logging.Severity.High);
DisplayMessage.ErrorResultsText(filePath, ex.GetType().Name, "'1 Pass' erasure failed.");
}
}
public static void ZeroFill(string filePath, bool useOnes, BackgroundWorker bgwShredFiles)
{
try
{
using (var fileStream = new FileStream(filePath, FileMode.Open, FileAccess.ReadWrite, FileShare.Read))
{
byte[] zeroes = FileHandling.GetBufferSize(fileStream);
if (useOnes == true)
{
zeroes = FillArrayWithOnes(zeroes);
}
while (fileStream.Position < fileStream.Length)
{
fileStream.Write(zeroes, 0, zeroes.Length);
ReportProgress.ReportEncryptionProgress(fileStream.Position, fileStream.Length, bgwShredFiles);
}
}
}
catch (Exception ex) when(ExceptionFilters.FileAccessExceptions(ex))
{
Logging.LogException(ex.ToString(), Logging.Severity.High);
DisplayMessage.ErrorResultsText(filePath, ex.GetType().Name, "'Zero fill' erasure failed.");
}
}
