C# and Data Encryption

Question

C++ / C#

It is necessary to encrypt text files with various encryption algorithms (DES, AES, Blowfish, etc.) Can anyone tell me which libraries to use and are there any standard ones? And their documentation.

Answer 1

in .net, classes for working with cryptography are in the System.Security.Cryptography namespace

Answer 2

/// /// Шифрует строку value
///
/// Строка которую необходимо зашифровать
/// Ключ шифрования
public static string Encrypt(string str, string keyCrypt)
{
return Convert.ToBase64String(Encrypt(Encoding.UTF8.GetBytes(str), keyCrypt));
}
/// /// Расшифроывает данные из строки value
///
/// Зашифрованая строка
/// Ключ шифрования
/// Возвращает null, если прочесть данные не удалось
[DebuggerNonUserCodeAttribute]
public static string Decrypt(string str, string keyCrypt)
{
string Result;
try
{
CryptoStream Cs = InternalDecrypt(Convert.FromBase64String(str), keyCrypt);
StreamReader Sr = new StreamReader(Cs);
Result = Sr.ReadToEnd();
Cs.Close();
Cs.Dispose();
Sr.Close();
Sr.Dispose();
}
catch (CryptographicException)
{
return null;
}
return Result;
}
private static byte[] Encrypt(byte[] key, string value)
{
SymmetricAlgorithm Sa = Rijndael.Create();
ICryptoTransform Ct = Sa.CreateEncryptor((new PasswordDeriveBytes(value, null)).GetBytes(16), new byte[16]);
MemoryStream Ms = new MemoryStream();
CryptoStream Cs = new CryptoStream(Ms, Ct, CryptoStreamMode.Write);
Cs.Write(key, 0, key.Length);
Cs.FlushFinalBlock();
byte[] Result = Ms.ToArray();
Ms.Close();
Ms.Dispose();
Cs.Close();
Cs.Dispose();
Ct.Dispose();
return Result;
}
private static CryptoStream InternalDecrypt(byte[] key, string value)
{
SymmetricAlgorithm sa = Rijndael.Create();
ICryptoTransform ct = sa.CreateDecryptor((new PasswordDeriveBytes(value, null)).GetBytes(16), new byte[16]);
MemoryStream ms = new MemoryStream(key);
return new CryptoStream(ms, ct, CryptoStreamMode.Read);
}

Working code from a real project.

Answer 3

There is nothing.

Answer 4

There is a Bouncy Castle library

Answer 5

msdn.microsoft.com/en-us/library/92f9ye3s.aspx

Answer 6

Parsing and implementation of the DES algorithm is, for example, here (there is also RSA). It seems clear.