static bool IsValidKey(byte[] key)
{
using (var Aes = new AesManaged())
{
var bitLength = key.Length * 8;
var maxValidKeyBitLength = Aes.LegalKeySizes.Max(keyLength => keyLength.MaxSize);
if (bitLength < maxValidKeyBitLength)
{
Log.WarnFormat("Encryption key is {0} bits which is less than the maximum allowed {1} bits. Consider using a {1}-bit encryption key to obtain the maximum cipher strength", bitLength, maxValidKeyBitLength);
}
return(Aes.ValidKeySize(bitLength));
}
}
internal AesEncryptionResult EncryptWithMemoryStream(byte[] sourceData, byte[] key = null, byte[] IV = null, CipherMode cipherMode = CipherMode.CBC,
PaddingMode paddingMode = PaddingMode.PKCS7)
{
if (sourceData == null || sourceData.Length == 0)
{
return(new AesEncryptionResult()
{
Success = false,
Message = MessageStrings.Encryption_InputRequired
});
}
_key = key ?? _key;
_IV = IV ?? _IV;
byte[] encryptedData = null;
try
{
using (var aesManaged = new AesManaged())
{
if (_key == null)
{
aesManaged.GenerateKey();
_key = aesManaged.Key;
}
else
{
if (aesManaged.ValidKeySize((_key.Length * 8)))
{
aesManaged.Key = _key;
}
else
{
return(new AesEncryptionResult()
{
Success = false,
Message = $"{MessageStrings.Common_InvalidKeySizeError} ({(_key.Length * 8)})."
});
}
}
if (_IV == null)
{
aesManaged.GenerateIV();
_IV = aesManaged.IV;
}
else
{
aesManaged.IV = _IV;
}
aesManaged.Mode = cipherMode;
aesManaged.Padding = paddingMode;
using (var encryptor = aesManaged.CreateEncryptor(_key, _IV))
{
using (var ms = new MemoryStream())
{
using (var cs = new CryptoStream(ms, encryptor, CryptoStreamMode.Write))
{
using (var bw = new BinaryWriter(cs))
{
bw.Write(sourceData);
}
}
encryptedData = ms.ToArray();
}
}
}
}
catch (Exception ex)
{
return(new AesEncryptionResult()
{
Success = false,
Message = $"{MessageStrings.Encryption_ExceptionError}\n{ex.ToString()}"
});
}
return(new AesEncryptionResult()
{
Success = true,
Message = MessageStrings.Encryption_EncryptSuccess,
EncryptedDataBytes = encryptedData,
EncryptedDataBase64String = Convert.ToBase64String(encryptedData),
Key = _key,
IV = _IV,
AesCipherMode = (AesCipherMode)cipherMode,
PaddingMode = paddingMode
});
}
internal AesEncryptionResult EncryptWithFileStream(string sourceFilePath, string encryptedFilePath, byte[] key = null, byte[] IV = null, CipherMode cipherMode = CipherMode.CBC,
PaddingMode paddingMode = PaddingMode.PKCS7, bool deleteSourceFile = false, int kBbufferSize = 4)
{
if (!File.Exists(sourceFilePath))
{
return(new AesEncryptionResult()
{
Success = false,
//Message = $"{MessageStrings.Common_FileNotFound} \"{sourceFilePath}\"."
Message = $"{MessageStrings.Common_FileNotFound} \"{sourceFilePath}\"."
});
}
if (string.IsNullOrWhiteSpace(encryptedFilePath))
{
return(new AesEncryptionResult()
{
Success = false,
Message = MessageStrings.Encryption_EncryptedFilePathError
});
}
var destinationDirectory = Path.GetDirectoryName(encryptedFilePath);
if (!Directory.Exists(destinationDirectory))
{
return(new AesEncryptionResult()
{
Success = false,
Message = $"{MessageStrings.Encryption_DestinationDirectoryNotFound} \"{destinationDirectory}\"."
});
}
_key = key ?? _key;
_IV = IV ?? _IV;
var pathsEqual = encryptedFilePath.Equals(sourceFilePath, StringComparison.InvariantCultureIgnoreCase);
try
{
using (var aesManaged = new AesManaged())
{
if (_key == null)
{
aesManaged.GenerateKey();
_key = aesManaged.Key;
}
else
{
if (aesManaged.ValidKeySize((_key.Length * 8)))
{
aesManaged.Key = _key;
}
else
{
return(new AesEncryptionResult()
{
Success = false,
Message = $"{MessageStrings.Common_InvalidKeySizeError} ({(_key.Length * 8)})."
});
}
}
if (_IV == null || _IV.Length == 0)
{
aesManaged.GenerateIV();
_IV = aesManaged.IV;
}
else
{
aesManaged.IV = _IV;
}
aesManaged.Mode = cipherMode;
aesManaged.Padding = paddingMode;
using (var encryptor = aesManaged.CreateEncryptor(_key, _IV))
{
using (var sourceFs = File.Open(sourceFilePath, FileMode.Open, FileAccess.Read, FileShare.Read))
{
using (var encryptedFs = File.Open((pathsEqual ? encryptedFilePath + "_tmpcrypt" : encryptedFilePath), FileMode.Create, FileAccess.Write, FileShare.None))
{
using (var cs = new CryptoStream(encryptedFs, encryptor, CryptoStreamMode.Write))
{
//plain.CopyTo(cs);
var buffer = new byte[kBbufferSize * 1024];
int read;
var percentageDone = 0;
while ((read = sourceFs.Read(buffer, 0, buffer.Length)) > 0)
{
cs.Write(buffer, 0, read);
var tmpPercentageDone = (int)(sourceFs.Position * 100 / sourceFs.Length);
if (tmpPercentageDone != percentageDone)
{
percentageDone = tmpPercentageDone;
RaiseOnEncryptionProgress(percentageDone, (percentageDone != 100 ? $"Encrypting ({percentageDone}%)..." : $"Encrypted ({percentageDone}%)."));
}
}
}
}
}
}
}
if (pathsEqual)
{
CommonMethods.ClearFileAttributes(sourceFilePath); // set "Normal" FileAttributes to avoid erros while trying to delete the file below
File.Delete(sourceFilePath);
File.Move(encryptedFilePath + "_tmpcrypt", encryptedFilePath);
}
if (deleteSourceFile && !pathsEqual)
{
CommonMethods.ClearFileAttributes(sourceFilePath); // set "Normal" FileAttributes to avoid erros while trying to delete the file below
File.Delete(sourceFilePath);
}
//var message = $"File \"{sourceFilePath}\" successfully encrypted to \"{encryptedFilePath}\".";
var message = string.Format(MessageStrings.Encryption_FileEncryptSuccess, sourceFilePath, encryptedFilePath);
message += (deleteSourceFile && !pathsEqual ? $"\n{string.Format(MessageStrings.Encryption_FileDeleted, sourceFilePath)}" : "");
return(new AesEncryptionResult()
{
Success = true,
Message = message,
Key = _key,
IV = _IV,
AesCipherMode = (AesCipherMode)cipherMode,
PaddingMode = paddingMode
});
}
catch (Exception ex)
{
return(new AesEncryptionResult()
{
Success = false,
Message = $"{MessageStrings.Encryption_ExceptionError}\n{ex.ToString()}"
});
}
}
internal AesDecryptionResult DecryptWithMemoryStream(byte[] encryptedData, byte[] key = null, byte[] IV = null, CipherMode cipherMode = CipherMode.CBC,
PaddingMode paddingMode = PaddingMode.PKCS7)
{
if (encryptedData == null || encryptedData.Length == 0)
{
return(new AesDecryptionResult()
{
Success = false,
Message = MessageStrings.Decryption_InputRequired
});
}
_key = key ?? _key;
_IV = IV ?? _IV;
if (_key == null)
{
return(new AesDecryptionResult()
{
Success = false,
Message = MessageStrings.Decryption_NullKeyError
});
}
if (_IV == null)
{
return(new AesDecryptionResult()
{
Success = false,
Message = MessageStrings.Decryption_NullIVError
});
}
byte[] decryptedData = null;
try
{
using (var aesManaged = new AesManaged())
{
if (aesManaged.ValidKeySize((_key.Length * 8)))
{
aesManaged.Key = _key;
}
else
{
return(new AesDecryptionResult()
{
Success = false,
Message = $"{MessageStrings.Common_InvalidKeySizeError} ({(_key.Length * 8)})."
});
}
aesManaged.IV = _IV;
aesManaged.Mode = cipherMode;
aesManaged.Padding = paddingMode;
using (var decryptor = aesManaged.CreateDecryptor(_key, _IV))
{
using (var ms = new MemoryStream())
{
using (var cs = new CryptoStream(ms, decryptor, CryptoStreamMode.Write))
{
using (var bw = new BinaryWriter(cs))
{
bw.Write(encryptedData);
}
}
decryptedData = ms.ToArray();
}
}
}
}
catch (Exception ex)
{
return(new AesDecryptionResult()
{
Success = false,
Message = $"{MessageStrings.Decryption_ExceptionError}\n{ex.ToString()}"
});
}
return(new AesDecryptionResult()
{
Success = true,
Message = MessageStrings.Decryption_DecryptSuccess,
DecryptedDataBytes = decryptedData,
DecryptedDataString = System.Text.Encoding.UTF8.GetString(decryptedData),
Key = _key,
IV = _IV,
AesCipherMode = (AesCipherMode)cipherMode,
PaddingMode = paddingMode
});
}
internal AesEncryptionResult EncryptWithMemoryStream(byte[] sourceData, byte[] key = null, byte[] IV = null, CipherMode cipherMode = CipherMode.CBC,
PaddingMode paddingMode = PaddingMode.PKCS7)
{
if (sourceData == null || sourceData.Length == 0)
{
return(new AesEncryptionResult()
{
Success = false,
Message = "Source data cannot be null or 0 bytes."
});
}
_key = key;
_IV = IV;
_cipherMode = cipherMode;
_paddingMode = paddingMode;
byte[] encryptedData = null;
try
{
using (AesManaged aesManaged = new AesManaged())
{
if (_key == null)
{
aesManaged.GenerateKey();
_key = aesManaged.Key;
}
else
{
if (aesManaged.ValidKeySize((_key.Length * 8)))
{
aesManaged.Key = _key;
}
else
{
return(new AesEncryptionResult()
{
Success = false,
Message = $"Invalid key bit size ({(_key.Length * 8)})."
});
}
}
if (_IV == null)
{
aesManaged.GenerateIV();
_IV = aesManaged.IV;
}
else
{
aesManaged.IV = _IV;
}
aesManaged.Mode = _cipherMode;
aesManaged.Padding = _paddingMode;
using (var encryptor = aesManaged.CreateEncryptor(_key, _IV))
{
using (var ms = new MemoryStream())
{
using (var cs = new CryptoStream(ms, encryptor, CryptoStreamMode.Write))
{
using (var bw = new BinaryWriter(cs))
{
bw.Write(sourceData);
}
}
encryptedData = ms.ToArray();
}
}
}
}
catch (Exception ex)
{
return(new AesEncryptionResult()
{
Success = false,
Message = $"Error while trying to encrypt data:\n{ex.ToString()}"
});
}
return(new AesEncryptionResult()
{
Success = true,
Message = "Data succesfully encrypted.",
EncryptedDataBytes = encryptedData,
EncryptedDataBase64String = Convert.ToBase64String(encryptedData),
Key = _key,
IV = _IV,
AesCipherMode = (AesCipherMode)_cipherMode,
PaddingMode = _paddingMode
});
}
internal AesDecryptionResult DecryptWithMemoryStream(byte[] encryptedData, byte[] key, byte[] IV, CipherMode cipherMode = CipherMode.CBC,
PaddingMode paddingMode = PaddingMode.PKCS7)
{
if (encryptedData == null || encryptedData.Length == 0)
{
return(new AesDecryptionResult()
{
Success = false,
Message = "Encrypted data cannot be null or 0 bytes."
});
}
if (key == null)
{
return(new AesDecryptionResult()
{
Success = false,
Message = "Key cannot be null."
});
}
if (IV == null)
{
return(new AesDecryptionResult()
{
Success = false,
Message = "IV cannot be null."
});
}
_key = key;
_IV = IV;
_cipherMode = cipherMode;
_paddingMode = paddingMode;
byte[] decryptedData = null;
try
{
using (AesManaged aesManaged = new AesManaged())
{
if (aesManaged.ValidKeySize((_key.Length * 8)))
{
aesManaged.Key = _key;
}
else
{
return(new AesDecryptionResult()
{
Success = false,
Message = $"Invalid key bit size ({(_key.Length * 8)})."
});
}
aesManaged.IV = _IV;
aesManaged.Mode = _cipherMode;
aesManaged.Padding = _paddingMode;
using (var decryptor = aesManaged.CreateDecryptor(_key, _IV))
{
using (var ms = new MemoryStream())
{
using (var cs = new CryptoStream(ms, decryptor, CryptoStreamMode.Write))
{
using (var bw = new BinaryWriter(cs))
{
bw.Write(encryptedData);
}
}
decryptedData = ms.ToArray();
}
}
}
}
catch (Exception ex)
{
return(new AesDecryptionResult()
{
Success = false,
Message = $"Error while trying to decrypt data:\n{ex.ToString()}"
});
}
return(new AesDecryptionResult()
{
Success = true,
Message = "Data succesfully decrypted.",
DecryptedDataBytes = decryptedData,
DecryptedDataString = Encoding.UTF8.GetString(decryptedData),
Key = _key,
IV = _IV,
AesCipherMode = (AesCipherMode)_cipherMode,
PaddingMode = _paddingMode
});
}