Я не могу найти хороший чистый пример использования 128-битного шифрования AES.
Есть ли у кого-нибудь пример кода?
Использование AES-шифрования в С#
Ответ 1
Если вы просто хотите использовать встроенный крипторесурс RijndaelManaged, ознакомьтесь со следующей статьей справки (у нее также есть простой пример кода):
http://msdn.microsoft.com/en-us/library/system.security.cryptography.rijndaelmanaged.aspx
И на всякий случай вам нужен образец в спешке, вот он во всей своей плагиативной славе:
using System;
using System.IO;
using System.Security.Cryptography;
namespace RijndaelManaged_Example
{
class RijndaelExample
{
public static void Main()
{
try
{
string original = "Here is some data to encrypt!";
// Create a new instance of the RijndaelManaged
// class. This generates a new key and initialization
// vector (IV).
using (RijndaelManaged myRijndael = new RijndaelManaged())
{
myRijndael.GenerateKey();
myRijndael.GenerateIV();
// Encrypt the string to an array of bytes.
byte[] encrypted = EncryptStringToBytes(original, myRijndael.Key, myRijndael.IV);
// Decrypt the bytes to a string.
string roundtrip = DecryptStringFromBytes(encrypted, myRijndael.Key, myRijndael.IV);
//Display the original data and the decrypted data.
Console.WriteLine("Original: {0}", original);
Console.WriteLine("Round Trip: {0}", roundtrip);
}
}
catch (Exception e)
{
Console.WriteLine("Error: {0}", e.Message);
}
}
static byte[] EncryptStringToBytes(string plainText, byte[] Key, byte[] IV)
{
// Check arguments.
if (plainText == null || plainText.Length <= 0)
throw new ArgumentNullException("plainText");
if (Key == null || Key.Length <= 0)
throw new ArgumentNullException("Key");
if (IV == null || IV.Length <= 0)
throw new ArgumentNullException("IV");
byte[] encrypted;
// Create an RijndaelManaged object
// with the specified key and IV.
using (RijndaelManaged rijAlg = new RijndaelManaged())
{
rijAlg.Key = Key;
rijAlg.IV = IV;
// Create a decryptor to perform the stream transform.
ICryptoTransform encryptor = rijAlg.CreateEncryptor(rijAlg.Key, rijAlg.IV);
// Create the streams used for encryption.
using (MemoryStream msEncrypt = new MemoryStream())
{
using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
{
using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
{
//Write all data to the stream.
swEncrypt.Write(plainText);
}
encrypted = msEncrypt.ToArray();
}
}
}
// Return the encrypted bytes from the memory stream.
return encrypted;
}
static string DecryptStringFromBytes(byte[] cipherText, byte[] Key, byte[] IV)
{
// Check arguments.
if (cipherText == null || cipherText.Length <= 0)
throw new ArgumentNullException("cipherText");
if (Key == null || Key.Length <= 0)
throw new ArgumentNullException("Key");
if (IV == null || IV.Length <= 0)
throw new ArgumentNullException("IV");
// Declare the string used to hold
// the decrypted text.
string plaintext = null;
// Create an RijndaelManaged object
// with the specified key and IV.
using (RijndaelManaged rijAlg = new RijndaelManaged())
{
rijAlg.Key = Key;
rijAlg.IV = IV;
// Create a decrytor to perform the stream transform.
ICryptoTransform decryptor = rijAlg.CreateDecryptor(rijAlg.Key, rijAlg.IV);
// Create the streams used for decryption.
using (MemoryStream msDecrypt = new MemoryStream(cipherText))
{
using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
{
using (StreamReader srDecrypt = new StreamReader(csDecrypt))
{
// Read the decrypted bytes from the decrypting stream
// and place them in a string.
plaintext = srDecrypt.ReadToEnd();
}
}
}
}
return plaintext;
}
}
}
Ответ 2
Мне недавно приходилось сталкиваться с этим снова в моем собственном проекте - и мне хотелось поделиться более простым кодом, который я использовал, поскольку этот вопрос и серия ответов продолжались в моих поисках.
Я не буду беспокоиться о проблемах безопасности, связанных с тем, как часто обновлять такие вещи, как ваш Salt and Initialization Vector, - это тема для форума безопасности, и есть некоторые интересные возможности для изучения. Это просто блок кода для реализации AesManaged в С#.
using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
namespace Your.Namespace.Security {
public static class Cryptography {
#region Settings
private static int _iterations = 2;
private static int _keySize = 256;
private static string _hash = "SHA1";
private static string _salt = "aselrias38490a32"; // Random
private static string _vector = "8947az34awl34kjq"; // Random
#endregion
public static string Encrypt(string value, string password) {
return Encrypt<AesManaged>(value, password);
}
public static string Encrypt<T>(string value, string password)
where T : SymmetricAlgorithm, new() {
byte[] vectorBytes = GetBytes<ASCIIEncoding>(_vector);
byte[] saltBytes = GetBytes<ASCIIEncoding>(_salt);
byte[] valueBytes = GetBytes<UTF8Encoding>(value);
byte[] encrypted;
using (T cipher = new T()) {
PasswordDeriveBytes _passwordBytes =
new PasswordDeriveBytes(password, saltBytes, _hash, _iterations);
byte[] keyBytes = _passwordBytes.GetBytes(_keySize / 8);
cipher.Mode = CipherMode.CBC;
using (ICryptoTransform encryptor = cipher.CreateEncryptor(keyBytes, vectorBytes)) {
using (MemoryStream to = new MemoryStream()) {
using (CryptoStream writer = new CryptoStream(to, encryptor, CryptoStreamMode.Write)) {
writer.Write(valueBytes, 0, valueBytes.Length);
writer.FlushFinalBlock();
encrypted = to.ToArray();
}
}
}
cipher.Clear();
}
return Convert.ToBase64String(encrypted);
}
public static string Decrypt(string value, string password) {
return Decrypt<AesManaged>(value, password);
}
public static string Decrypt<T>(string value, string password) where T : SymmetricAlgorithm, new() {
byte[] vectorBytes = GetBytes<ASCIIEncoding>(_vector);
byte[] saltBytes = GetBytes<ASCIIEncoding>(_salt);
byte[] valueBytes = Convert.FromBase64String(value);
byte[] decrypted;
int decryptedByteCount = 0;
using (T cipher = new T()) {
PasswordDeriveBytes _passwordBytes = new PasswordDeriveBytes(password, saltBytes, _hash, _iterations);
byte[] keyBytes = _passwordBytes.GetBytes(_keySize / 8);
cipher.Mode = CipherMode.CBC;
try {
using (ICryptoTransform decryptor = cipher.CreateDecryptor(keyBytes, vectorBytes)) {
using (MemoryStream from = new MemoryStream(valueBytes)) {
using (CryptoStream reader = new CryptoStream(from, decryptor, CryptoStreamMode.Read)) {
decrypted = new byte[valueBytes.Length];
decryptedByteCount = reader.Read(decrypted, 0, decrypted.Length);
}
}
}
} catch (Exception ex) {
return String.Empty;
}
cipher.Clear();
}
return Encoding.UTF8.GetString(decrypted, 0, decryptedByteCount);
}
}
}
Код очень прост в использовании. Это буквально просто требует следующего:
string encrypted = Cryptography.Encrypt(data, "testpass");
string decrypted = Cryptography.Decrypt(encrypted, "testpass");
По умолчанию в реализации используется AesManaged, но вы также можете вставить любой другой SymmetricAlgorithm. Список доступных SymmetricAlgorithm наследователей для .NET 4.5 можно найти по адресу:
http://msdn.microsoft.com/en-us/library/system.security.cryptography.symmetricalgorithm.aspx
На момент публикации этого сообщения текущий список включает в себя:
-
AesManaged -
RijndaelManaged -
DESCryptoServiceProvider -
RC2CryptoServiceProvider -
TripleDESCryptoServiceProvider
Чтобы использовать RijndaelManaged с приведенным выше кодом, в качестве примера вы должны использовать:
string encrypted = Cryptography.Encrypt<RijndaelManaged>(dataToEncrypt, password);
string decrypted = Cryptography.Decrypt<RijndaelManaged>(encrypted, password);
Надеюсь, это поможет кому-то там.
Ответ 3
Посмотрите на образец здесь.
Пример в MSDN не работает нормально (возникает ошибка), потому что нет начального значения Начальный вектор (iv) и Ключ. Я добавляю 2 строки кода и теперь работаю нормально.
Подробнее см. ниже:
using System.Windows.Forms;
using System;
using System.Text;
using System.IO;
using System.Security.Cryptography;
namespace AES_TESTER
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
try
{
string original = "Here is some data to encrypt!";
MessageBox.Show("Original: " + original);
// Create a new instance of the RijndaelManaged
// class. This generates a new key and initialization
// vector (IV).
using (RijndaelManaged myRijndael = new RijndaelManaged())
{
myRijndael.GenerateKey();
myRijndael.GenerateIV();
// Encrypt the string to an array of bytes.
byte[] encrypted = EncryptStringToBytes(original, myRijndael.Key, myRijndael.IV);
StringBuilder s = new StringBuilder();
foreach (byte item in encrypted)
{
s.Append(item.ToString("X2") + " ");
}
MessageBox.Show("Encrypted: " + s);
// Decrypt the bytes to a string.
string decrypted = DecryptStringFromBytes(encrypted, myRijndael.Key, myRijndael.IV);
//Display the original data and the decrypted data.
MessageBox.Show("Decrypted: " + decrypted);
}
}
catch (Exception ex)
{
MessageBox.Show("Error: {0}", ex.Message);
}
}
static byte[] EncryptStringToBytes(string plainText, byte[] Key, byte[] IV)
{
// Check arguments.
if (plainText == null || plainText.Length <= 0)
throw new ArgumentNullException("plainText");
if (Key == null || Key.Length <= 0)
throw new ArgumentNullException("Key");
if (IV == null || IV.Length <= 0)
throw new ArgumentNullException("Key");
byte[] encrypted;
// Create an RijndaelManaged object
// with the specified key and IV.
using (RijndaelManaged rijAlg = new RijndaelManaged())
{
rijAlg.Key = Key;
rijAlg.IV = IV;
rijAlg.Mode = CipherMode.CBC;
rijAlg.Padding = PaddingMode.Zeros;
// Create a decrytor to perform the stream transform.
ICryptoTransform encryptor = rijAlg.CreateEncryptor(rijAlg.Key, rijAlg.IV);
// Create the streams used for encryption.
using (MemoryStream msEncrypt = new MemoryStream())
{
using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
{
using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
{
//Write all data to the stream.
swEncrypt.Write(plainText);
}
encrypted = msEncrypt.ToArray();
}
}
}
// Return the encrypted bytes from the memory stream.
return encrypted;
}
static string DecryptStringFromBytes(byte[] cipherText, byte[] Key, byte[] IV)
{
// Check arguments.
if (cipherText == null || cipherText.Length <= 0)
throw new ArgumentNullException("cipherText");
if (Key == null || Key.Length <= 0)
throw new ArgumentNullException("Key");
if (IV == null || IV.Length <= 0)
throw new ArgumentNullException("Key");
// Declare the string used to hold
// the decrypted text.
string plaintext = null;
// Create an RijndaelManaged object
// with the specified key and IV.
using (RijndaelManaged rijAlg = new RijndaelManaged())
{
rijAlg.Key = Key;
rijAlg.IV = IV;
rijAlg.Mode = CipherMode.CBC;
rijAlg.Padding = PaddingMode.Zeros;
// Create a decrytor to perform the stream transform.
ICryptoTransform decryptor = rijAlg.CreateDecryptor(rijAlg.Key, rijAlg.IV);
// Create the streams used for decryption.
using (MemoryStream msDecrypt = new MemoryStream(cipherText))
{
using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
{
using (StreamReader srDecrypt = new StreamReader(csDecrypt))
{
// Read the decrypted bytes from the decrypting stream
// and place them in a string.
plaintext = srDecrypt.ReadToEnd();
}
}
}
}
return plaintext;
}
}
}
Ответ 4
Использование AES или реализация AES? Для использования AES существует класс System.Security.Cryptography.RijndaelManaged.
Ответ 5
Для более полного примера, который выполняет деривацию ключа в дополнение к шифрованию AES, см. ответ и ссылки, размещенные в Получение шифрования AES для работы через Javascript и С#.
ИЗМЕНИТЬ
сторона примечание: Javascript Криптография считается вредной. Стоит прочитать.
Ответ 6
//Code to encrypt Data :
public byte[] encryptdata(byte[] bytearraytoencrypt, string key, string iv)
{
AesCryptoServiceProvider dataencrypt = new AesCryptoServiceProvider();
//Block size : Gets or sets the block size, in bits, of the cryptographic operation.
dataencrypt.BlockSize = 128;
//KeySize: Gets or sets the size, in bits, of the secret key
dataencrypt.KeySize = 128;
//Key: Gets or sets the symmetric key that is used for encryption and decryption.
dataencrypt.Key = System.Text.Encoding.UTF8.GetBytes(key);
//IV : Gets or sets the initialization vector (IV) for the symmetric algorithm
dataencrypt.IV = System.Text.Encoding.UTF8.GetBytes(iv);
//Padding: Gets or sets the padding mode used in the symmetric algorithm
dataencrypt.Padding = PaddingMode.PKCS7;
//Mode: Gets or sets the mode for operation of the symmetric algorithm
dataencrypt.Mode = CipherMode.CBC;
//Creates a symmetric AES encryptor object using the current key and initialization vector (IV).
ICryptoTransform crypto1 = dataencrypt.CreateEncryptor(dataencrypt.Key, dataencrypt.IV);
//TransformFinalBlock is a special function for transforming the last block or a partial block in the stream.
//It returns a new array that contains the remaining transformed bytes. A new array is returned, because the amount of
//information returned at the end might be larger than a single block when padding is added.
byte[] encrypteddata = crypto1.TransformFinalBlock(bytearraytoencrypt, 0, bytearraytoencrypt.Length);
crypto1.Dispose();
//return the encrypted data
return encrypteddata;
}
//code to decrypt data
private byte[] decryptdata(byte[] bytearraytodecrypt, string key, string iv)
{
AesCryptoServiceProvider keydecrypt = new AesCryptoServiceProvider();
keydecrypt.BlockSize = 128;
keydecrypt.KeySize = 128;
keydecrypt.Key = System.Text.Encoding.UTF8.GetBytes(key);
keydecrypt.IV = System.Text.Encoding.UTF8.GetBytes(iv);
keydecrypt.Padding = PaddingMode.PKCS7;
keydecrypt.Mode = CipherMode.CBC;
ICryptoTransform crypto1 = keydecrypt.CreateDecryptor(keydecrypt.Key, keydecrypt.IV);
byte[] returnbytearray = crypto1.TransformFinalBlock(bytearraytodecrypt, 0, bytearraytodecrypt.Length);
crypto1.Dispose();
return returnbytearray;
}
Ответ 7
Попробуйте этот код, может быть, полезно.
1.Создайте новый проект С# и добавьте код в форму Form1:
using System;
using System.Windows.Forms;
using System.Security.Cryptography;
namespace ExampleCrypto
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
string strOriginalData = string.Empty;
string strEncryptedData = string.Empty;
string strDecryptedData = string.Empty;
strOriginalData = "this is original data 1234567890"; // your original data in here
MessageBox.Show("ORIGINAL DATA:\r\n" + strOriginalData);
clsCrypto aes = new clsCrypto();
aes.IV = "this is your IV"; // your IV
aes.KEY = "this is your KEY"; // your KEY
strEncryptedData = aes.Encrypt(strOriginalData, CipherMode.CBC); // your cipher mode
MessageBox.Show("ENCRYPTED DATA:\r\n" + strEncryptedData);
strDecryptedData = aes.Decrypt(strEncryptedData, CipherMode.CBC);
MessageBox.Show("DECRYPTED DATA:\r\n" + strDecryptedData);
}
}
}
2.Создайте clsCrypto.cs и скопируйте вставку, следуя коду в своем классе и запустите свой код. Я использовал MD5 для создания начального вектора (IV) и KEY AES.
using System;
using System.Security.Cryptography;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Runtime.Remoting.Metadata.W3cXsd2001;
namespace ExampleCrypto
{
public class clsCrypto
{
private string _KEY = string.Empty;
protected internal string KEY
{
get
{
return _KEY;
}
set
{
if (!string.IsNullOrEmpty(value))
{
_KEY = value;
}
}
}
private string _IV = string.Empty;
protected internal string IV
{
get
{
return _IV;
}
set
{
if (!string.IsNullOrEmpty(value))
{
_IV = value;
}
}
}
private string CalcMD5(string strInput)
{
string strOutput = string.Empty;
if (!string.IsNullOrEmpty(strInput))
{
try
{
StringBuilder strHex = new StringBuilder();
using (MD5 md5 = MD5.Create())
{
byte[] bytArText = Encoding.Default.GetBytes(strInput);
byte[] bytArHash = md5.ComputeHash(bytArText);
for (int i = 0; i < bytArHash.Length; i++)
{
strHex.Append(bytArHash[i].ToString("X2"));
}
strOutput = strHex.ToString();
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
return strOutput;
}
private byte[] GetBytesFromHexString(string strInput)
{
byte[] bytArOutput = new byte[] { };
if ((!string.IsNullOrEmpty(strInput)) && strInput.Length % 2 == 0)
{
SoapHexBinary hexBinary = null;
try
{
hexBinary = SoapHexBinary.Parse(strInput);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
bytArOutput = hexBinary.Value;
}
return bytArOutput;
}
private byte[] GenerateIV()
{
byte[] bytArOutput = new byte[] { };
try
{
string strIV = CalcMD5(IV);
bytArOutput = GetBytesFromHexString(strIV);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
return bytArOutput;
}
private byte[] GenerateKey()
{
byte[] bytArOutput = new byte[] { };
try
{
string strKey = CalcMD5(KEY);
bytArOutput = GetBytesFromHexString(strKey);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
return bytArOutput;
}
protected internal string Encrypt(string strInput, CipherMode cipherMode)
{
string strOutput = string.Empty;
if (!string.IsNullOrEmpty(strInput))
{
try
{
byte[] bytePlainText = Encoding.Default.GetBytes(strInput);
using (RijndaelManaged rijManaged = new RijndaelManaged())
{
rijManaged.Mode = cipherMode;
rijManaged.BlockSize = 128;
rijManaged.KeySize = 128;
rijManaged.IV = GenerateIV();
rijManaged.Key = GenerateKey();
rijManaged.Padding = PaddingMode.Zeros;
ICryptoTransform icpoTransform = rijManaged.CreateEncryptor(rijManaged.Key, rijManaged.IV);
using (MemoryStream memStream = new MemoryStream())
{
using (CryptoStream cpoStream = new CryptoStream(memStream, icpoTransform, CryptoStreamMode.Write))
{
cpoStream.Write(bytePlainText, 0, bytePlainText.Length);
cpoStream.FlushFinalBlock();
}
strOutput = Encoding.Default.GetString(memStream.ToArray());
}
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
return strOutput;
}
protected internal string Decrypt(string strInput, CipherMode cipherMode)
{
string strOutput = string.Empty;
if (!string.IsNullOrEmpty(strInput))
{
try
{
byte[] byteCipherText = Encoding.Default.GetBytes(strInput);
byte[] byteBuffer = new byte[strInput.Length];
using (RijndaelManaged rijManaged = new RijndaelManaged())
{
rijManaged.Mode = cipherMode;
rijManaged.BlockSize = 128;
rijManaged.KeySize = 128;
rijManaged.IV = GenerateIV();
rijManaged.Key = GenerateKey();
rijManaged.Padding = PaddingMode.Zeros;
ICryptoTransform icpoTransform = rijManaged.CreateDecryptor(rijManaged.Key, rijManaged.IV);
using (MemoryStream memStream = new MemoryStream(byteCipherText))
{
using (CryptoStream cpoStream = new CryptoStream(memStream, icpoTransform, CryptoStreamMode.Read))
{
cpoStream.Read(byteBuffer, 0, byteBuffer.Length);
}
strOutput = Encoding.Default.GetString(byteBuffer);
}
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
return strOutput;
}
}
}
Ответ 8
http://www.codeproject.com/Articles/769741/Csharp-AES-bits-Encryption-Library-with-Salt
using System.Security.Cryptography;
using System.IO;
public byte[] AES_Encrypt(byte[] bytesToBeEncrypted, byte[] passwordBytes)
{
byte[] encryptedBytes = null;
byte[] saltBytes = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8 };
using (MemoryStream ms = new MemoryStream())
{
using (RijndaelManaged AES = new RijndaelManaged())
{
AES.KeySize = 256;
AES.BlockSize = 128;
var key = new Rfc2898DeriveBytes(passwordBytes, saltBytes, 1000);
AES.Key = key.GetBytes(AES.KeySize / 8);
AES.IV = key.GetBytes(AES.BlockSize / 8);
AES.Mode = CipherMode.CBC;
using (var cs = new CryptoStream(ms, AES.CreateEncryptor(), CryptoStreamMode.Write))
{
cs.Write(bytesToBeEncrypted, 0, bytesToBeEncrypted.Length);
cs.Close();
}
encryptedBytes = ms.ToArray();
}
}
return encryptedBytes;
}
public byte[] AES_Decrypt(byte[] bytesToBeDecrypted, byte[] passwordBytes)
{
byte[] decryptedBytes = null;
byte[] saltBytes = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8 };
using (MemoryStream ms = new MemoryStream())
{
using (RijndaelManaged AES = new RijndaelManaged())
{
AES.KeySize = 256;
AES.BlockSize = 128;
var key = new Rfc2898DeriveBytes(passwordBytes, saltBytes, 1000);
AES.Key = key.GetBytes(AES.KeySize / 8);
AES.IV = key.GetBytes(AES.BlockSize / 8);
AES.Mode = CipherMode.CBC;
using (var cs = new CryptoStream(ms, AES.CreateDecryptor(), CryptoStreamMode.Write))
{
cs.Write(bytesToBeDecrypted, 0, bytesToBeDecrypted.Length);
cs.Close();
}
decryptedBytes = ms.ToArray();
}
}
return decryptedBytes;
}
Ответ 9
Вы можете использовать пароль из текстового поля, например... С помощью этого кода вы можете шифровать/дешифровать текст, изображение, документ Word, PDF....
public class Rijndael
{
private byte[] key;
private readonly byte[] vector = { 255, 64, 191, 111, 23, 3, 113, 119, 231, 121, 252, 112, 79, 32, 114, 156 };
ICryptoTransform EnkValue, DekValue;
public Rijndael(byte[] key)
{
this.key = key;
RijndaelManaged rm = new RijndaelManaged();
rm.Padding = PaddingMode.PKCS7;
EnkValue = rm.CreateEncryptor(key, vector);
DekValue = rm.CreateDecryptor(key, vector);
}
public byte[] Encrypt(byte[] byte)
{
byte[] enkByte= byte;
byte[] enkNewByte;
using (MemoryStream ms = new MemoryStream())
{
using (CryptoStream cs = new CryptoStream(ms, EnkValue, CryptoStreamMode.Write))
{
cs.Write(enkByte, 0, enkByte.Length);
cs.FlushFinalBlock();
ms.Position = 0;
enkNewByte= new byte[ms.Length];
ms.Read(enkNewByte, 0, enkNewByte.Length);
}
}
return enkNeyByte;
}
public byte[] Dekrypt(byte[] enkByte)
{
byte[] dekByte;
using (MemoryStream ms = new MemoryStream())
{
using (CryptoStream cs = new CryptoStream(ms, DekValue, CryptoStreamMode.Write))
{
cs.Write(enkByte, 0, enkByte.Length);
cs.FlushFinalBlock();
ms.Position = 0;
dekByte= new byte[ms.Length];
ms.Read(dekByte, 0, dekByte.Length);
}
}
return dekByte;
}
}
Преобразование пароля из текстового поля в массив байтов...
private byte[] ConvertPasswordToByte(string password)
{
byte[] key = new byte[32];
for (int i = 0; i < passwprd.Length; i++)
{
key[i] = Convert.ToByte(passwprd[i]);
}
return key;
}
Ответ 10
вот аккуратный и чистый код, чтобы понять алгоритм AES 256, реализованный в С#
вызов функции шифрования как encryptedstring = cryptObj.Encrypt(username, "AGARAMUDHALA", "EZHUTHELLAM", "SHA1", 3, "@1B2c3D4e5F6g7H8", 256);
public class Crypt
{
public string Encrypt(string passtext, string passPhrase, string saltV, string hashstring, int Iterations, string initVect, int keysize)
{
string functionReturnValue = null;
// Convert strings into byte arrays.
// Let us assume that strings only contain ASCII codes.
// If strings include Unicode characters, use Unicode, UTF7, or UTF8
// encoding.
byte[] initVectorBytes = null;
initVectorBytes = Encoding.ASCII.GetBytes(initVect);
byte[] saltValueBytes = null;
saltValueBytes = Encoding.ASCII.GetBytes(saltV);
// Convert our plaintext into a byte array.
// Let us assume that plaintext contains UTF8-encoded characters.
byte[] plainTextBytes = null;
plainTextBytes = Encoding.UTF8.GetBytes(passtext);
// First, we must create a password, from which the key will be derived.
// This password will be generated from the specified passphrase and
// salt value. The password will be created using the specified hash
// algorithm. Password creation can be done in several iterations.
PasswordDeriveBytes password = default(PasswordDeriveBytes);
password = new PasswordDeriveBytes(passPhrase, saltValueBytes, hashstring, Iterations);
// Use the password to generate pseudo-random bytes for the encryption
// key. Specify the size of the key in bytes (instead of bits).
byte[] keyBytes = null;
keyBytes = password.GetBytes(keysize/8);
// Create uninitialized Rijndael encryption object.
RijndaelManaged symmetricKey = default(RijndaelManaged);
symmetricKey = new RijndaelManaged();
// It is reasonable to set encryption mode to Cipher Block Chaining
// (CBC). Use default options for other symmetric key parameters.
symmetricKey.Mode = CipherMode.CBC;
// Generate encryptor from the existing key bytes and initialization
// vector. Key size will be defined based on the number of the key
// bytes.
ICryptoTransform encryptor = default(ICryptoTransform);
encryptor = symmetricKey.CreateEncryptor(keyBytes, initVectorBytes);
// Define memory stream which will be used to hold encrypted data.
MemoryStream memoryStream = default(MemoryStream);
memoryStream = new MemoryStream();
// Define cryptographic stream (always use Write mode for encryption).
CryptoStream cryptoStream = default(CryptoStream);
cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write);
// Start encrypting.
cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
// Finish encrypting.
cryptoStream.FlushFinalBlock();
// Convert our encrypted data from a memory stream into a byte array.
byte[] cipherTextBytes = null;
cipherTextBytes = memoryStream.ToArray();
// Close both streams.
memoryStream.Close();
cryptoStream.Close();
// Convert encrypted data into a base64-encoded string.
string cipherText = null;
cipherText = Convert.ToBase64String(cipherTextBytes);
functionReturnValue = cipherText;
return functionReturnValue;
}
public string Decrypt(string cipherText, string passPhrase, string saltValue, string hashAlgorithm, int passwordIterations, string initVector, int keySize)
{
string functionReturnValue = null;
// Convert strings defining encryption key characteristics into byte
// arrays. Let us assume that strings only contain ASCII codes.
// If strings include Unicode characters, use Unicode, UTF7, or UTF8
// encoding.
byte[] initVectorBytes = null;
initVectorBytes = Encoding.ASCII.GetBytes(initVector);
byte[] saltValueBytes = null;
saltValueBytes = Encoding.ASCII.GetBytes(saltValue);
// Convert our ciphertext into a byte array.
byte[] cipherTextBytes = null;
cipherTextBytes = Convert.FromBase64String(cipherText);
// First, we must create a password, from which the key will be
// derived. This password will be generated from the specified
// passphrase and salt value. The password will be created using
// the specified hash algorithm. Password creation can be done in
// several iterations.
PasswordDeriveBytes password = default(PasswordDeriveBytes);
password = new PasswordDeriveBytes(passPhrase, saltValueBytes, hashAlgorithm, passwordIterations);
// Use the password to generate pseudo-random bytes for the encryption
// key. Specify the size of the key in bytes (instead of bits).
byte[] keyBytes = null;
keyBytes = password.GetBytes(keySize / 8);
// Create uninitialized Rijndael encryption object.
RijndaelManaged symmetricKey = default(RijndaelManaged);
symmetricKey = new RijndaelManaged();
// It is reasonable to set encryption mode to Cipher Block Chaining
// (CBC). Use default options for other symmetric key parameters.
symmetricKey.Mode = CipherMode.CBC;
// Generate decryptor from the existing key bytes and initialization
// vector. Key size will be defined based on the number of the key
// bytes.
ICryptoTransform decryptor = default(ICryptoTransform);
decryptor = symmetricKey.CreateDecryptor(keyBytes, initVectorBytes);
// Define memory stream which will be used to hold encrypted data.
MemoryStream memoryStream = default(MemoryStream);
memoryStream = new MemoryStream(cipherTextBytes);
// Define memory stream which will be used to hold encrypted data.
CryptoStream cryptoStream = default(CryptoStream);
cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read);
// Since at this point we don't know what the size of decrypted data
// will be, allocate the buffer long enough to hold ciphertext;
// plaintext is never longer than ciphertext.
byte[] plainTextBytes = null;
plainTextBytes = new byte[cipherTextBytes.Length + 1];
// Start decrypting.
int decryptedByteCount = 0;
decryptedByteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length);
// Close both streams.
memoryStream.Close();
cryptoStream.Close();
// Convert decrypted data into a string.
// Let us assume that the original plaintext string was UTF8-encoded.
string plainText = null;
plainText = Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount);
// Return decrypted string.
functionReturnValue = plainText;
return functionReturnValue;
}
}