将使用此代码的应用程序必须足够安全,以加密SECRET级别的机密数据。
我知道rijndaelManaged类没有经过FIPS批准,但这不会影响安全性,所以我认为只要文件加密并使用相同的方法解密就可以了。应用。
此加密代码对于机密信息是否足够安全?
public static class AESEncryption
{
private static readonly byte[] initVectorBytes = Encoding.ASCII.GetBytes("tu89geji340t89u2");
private const int keysize = 256;
public static string Encrypt(string plainText, string passPhrase)
{
byte[] plainTextBytes = Encoding.UTF8.GetBytes(plainText);
using (PasswordDeriveBytes password = new PasswordDeriveBytes(passPhrase, null))
{
byte[] keyBytes = password.GetBytes(keysize / 8);
using (RijndaelManaged symmetricKey = new RijndaelManaged())
{
symmetricKey.Mode = CipherMode.CBC;
using (ICryptoTransform encryptor = symmetricKey.CreateEncryptor(keyBytes, initVectorBytes))
{
using (MemoryStream memoryStream = new MemoryStream())
{
using (CryptoStream cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))
{
cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
cryptoStream.FlushFinalBlock();
byte[] cipherTextBytes = memoryStream.ToArray();
return Convert.ToBase64String(cipherTextBytes);
}
}
}
}
}
}
public static string Decrypt(string cipherText, string passPhrase)
{
byte[] cipherTextBytes = Convert.FromBase64String(cipherText);
using (PasswordDeriveBytes password = new PasswordDeriveBytes(passPhrase, null))
{
byte[] keyBytes = password.GetBytes(keysize / 8);
using (RijndaelManaged symmetricKey = new RijndaelManaged())
{
symmetricKey.Mode = CipherMode.CBC;
using (ICryptoTransform decryptor = symmetricKey.CreateDecryptor(keyBytes, initVectorBytes))
{
using (MemoryStream memoryStream = new MemoryStream(cipherTextBytes))
{
using (CryptoStream cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read))
{
byte[] plainTextBytes = new byte[cipherTextBytes.Length];
int decryptedByteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length);
return Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount);
}
}
}
}
}
}
}
答案 0 :(得分:4)
您未使用经过身份验证的加密。这允许攻击修改消息,尽管他无法读取消息。
您使用的是常数IV 。这是一个信息泄露,因为攻击者可以判断您是否多次加密相同的消息。
IV的目的不是硬编码为某些特定值。让crypto API为您生成一个。
您很容易受到Padding Oracle攻击,因为您泄漏了检测到无效填充的信息。
除了这些问题之外,这段代码看起来还不错。
我建议您使用适用于.NET的AES-GCM。它是一个加密和验证数据的集成原语。很难出错。