在 C# 中加密和解密字符串？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/202011/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
提示：将鼠标放在中文语句上可以显示对应的英文。显示中英文
时间：2020-08-03 17:49:16 来源:igfitidea点击:
Encrypt and decrypt a string in C#?
提问by NotDan
How can I encrypt and decrypt a string in C#?
如何在 C# 中加密和解密字符串？
回答by Tamas Czinege
Here is an example using RSA.
这是使用 RSA 的示例。
Important:There is a limit to the size of data you can encrypt with the RSA encryption, KeySize - MinimumPadding. e.g. 256 bytes (assuming 2048 bit key) - 42 bytes (min OEAP padding) = 214 bytes (max plaintext size)
重要提示：您可以使用 RSA 加密加密的数据大小有限制KeySize - MinimumPadding。例如 256 字节（假设 2048 位密钥）- 42 字节（最小 OEAP 填充）= 214 字节（最大明文大小）
Replace your_rsa_key with your RSA key.
将 your_rsa_key 替换为您的 RSA 密钥。
var provider = new System.Security.Cryptography.RSACryptoServiceProvider();
provider.ImportParameters(your_rsa_key);
var encryptedBytes = provider.Encrypt(
System.Text.Encoding.UTF8.GetBytes("Hello World!"), true);
string decryptedTest = System.Text.Encoding.UTF8.GetString(
provider.Decrypt(encryptedBytes, true));
For more info, visit MSDN - RSACryptoServiceProvider
有关更多信息，请访问MSDN - RSACryptoServiceProvider
回答by Brett
EDIT 2013-Oct: Although I've edited this answer over time to address shortcomings, please see jbtule's answerfor a more robust, informed solution.
编辑 2013 年 10 月：虽然我已经随着时间的推移编辑了这个答案以解决缺点，但请参阅jbtule 的答案以获得更强大、更明智的解决方案。
https://stackoverflow.com/a/10366194/188474
https://stackoverflow.com/a/10366194/188474
Original Answer:
原答案：
Here's a working example derived from the "RijndaelManaged Class" documentationand the MCTS Training Kit.
这是从“RijndaelManaged Class”文档和MCTS Training Kit派生的工作示例。
EDIT 2012-April: This answer was edited to pre-pend the IV per jbtule's suggestion and as illustrated here:
编辑 2012 年 4 月：编辑此答案以根据 jbtule 的建议预先设置 IV，如下所示：
http://msdn.microsoft.com/en-us/library/system.security.cryptography.aesmanaged%28v=vs.95%29.aspx
http://msdn.microsoft.com/en-us/library/system.security.cryptography.aesmanaged%28v=vs.95%29.aspx
Good luck!
祝你好运！
public class Crypto
{
//While an app specific salt is not the best practice for
//password based encryption, it's probably safe enough as long as
//it is truly uncommon. Also too much work to alter this answer otherwise.
private static byte[] _salt = __To_Do__("Add a app specific salt here");
/// <summary>
/// Encrypt the given string using AES. The string can be decrypted using
/// DecryptStringAES(). The sharedSecret parameters must match.
/// </summary>
/// <param name="plainText">The text to encrypt.</param>
/// <param name="sharedSecret">A password used to generate a key for encryption.</param>
public static string EncryptStringAES(string plainText, string sharedSecret)
{
if (string.IsNullOrEmpty(plainText))
throw new ArgumentNullException("plainText");
if (string.IsNullOrEmpty(sharedSecret))
throw new ArgumentNullException("sharedSecret");
string outStr = null; // Encrypted string to return
RijndaelManaged aesAlg = null; // RijndaelManaged object used to encrypt the data.
try
{
// generate the key from the shared secret and the salt
Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(sharedSecret, _salt);
// Create a RijndaelManaged object
aesAlg = new RijndaelManaged();
aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);
// Create a decryptor to perform the stream transform.
ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);
// Create the streams used for encryption.
using (MemoryStream msEncrypt = new MemoryStream())
{
// prepend the IV
msEncrypt.Write(BitConverter.GetBytes(aesAlg.IV.Length), 0, sizeof(int));
msEncrypt.Write(aesAlg.IV, 0, aesAlg.IV.Length);
using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
{
using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
{
//Write all data to the stream.
swEncrypt.Write(plainText);
}
}
outStr = Convert.ToBase64String(msEncrypt.ToArray());
}
}
finally
{
// Clear the RijndaelManaged object.
if (aesAlg != null)
aesAlg.Clear();
}
// Return the encrypted bytes from the memory stream.
return outStr;
}
/// <summary>
/// Decrypt the given string. Assumes the string was encrypted using
/// EncryptStringAES(), using an identical sharedSecret.
/// </summary>
/// <param name="cipherText">The text to decrypt.</param>
/// <param name="sharedSecret">A password used to generate a key for decryption.</param>
public static string DecryptStringAES(string cipherText, string sharedSecret)
{
if (string.IsNullOrEmpty(cipherText))
throw new ArgumentNullException("cipherText");
if (string.IsNullOrEmpty(sharedSecret))
throw new ArgumentNullException("sharedSecret");
// Declare the RijndaelManaged object
// used to decrypt the data.
RijndaelManaged aesAlg = null;
// Declare the string used to hold
// the decrypted text.
string plaintext = null;
try
{
// generate the key from the shared secret and the salt
Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(sharedSecret, _salt);
// Create the streams used for decryption.
byte[] bytes = Convert.FromBase64String(cipherText);
using (MemoryStream msDecrypt = new MemoryStream(bytes))
{
// Create a RijndaelManaged object
// with the specified key and IV.
aesAlg = new RijndaelManaged();
aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);
// Get the initialization vector from the encrypted stream
aesAlg.IV = ReadByteArray(msDecrypt);
// Create a decrytor to perform the stream transform.
ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);
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();
}
}
}
finally
{
// Clear the RijndaelManaged object.
if (aesAlg != null)
aesAlg.Clear();
}
return plaintext;
}
private static byte[] ReadByteArray(Stream s)
{
byte[] rawLength = new byte[sizeof(int)];
if (s.Read(rawLength, 0, rawLength.Length) != rawLength.Length)
{
throw new SystemException("Stream did not contain properly formatted byte array");
}
byte[] buffer = new byte[BitConverter.ToInt32(rawLength, 0)];
if (s.Read(buffer, 0, buffer.Length) != buffer.Length)
{
throw new SystemException("Did not read byte array properly");
}
return buffer;
}
}
回答by BPL
using System;
using System.Data;
using System.Configuration;
using System.Text;
using System.Security.Cryptography;
namespace Encription
{
class CryptorEngine
{
public static string Encrypt(string ToEncrypt, bool useHasing)
{
byte[] keyArray;
byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(ToEncrypt);
//System.Configuration.AppSettingsReader settingsReader = new AppSettingsReader();
string Key = "Bhagwati";
if (useHasing)
{
MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(Key));
hashmd5.Clear();
}
else
{
keyArray = UTF8Encoding.UTF8.GetBytes(Key);
}
TripleDESCryptoServiceProvider tDes = new TripleDESCryptoServiceProvider();
tDes.Key = keyArray;
tDes.Mode = CipherMode.ECB;
tDes.Padding = PaddingMode.PKCS7;
ICryptoTransform cTransform = tDes.CreateEncryptor();
byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
tDes.Clear();
return Convert.ToBase64String(resultArray, 0, resultArray.Length);
}
public static string Decrypt(string cypherString, bool useHasing)
{
byte[] keyArray;
byte[] toDecryptArray = Convert.FromBase64String(cypherString);
//byte[] toEncryptArray = Convert.FromBase64String(cypherString);
//System.Configuration.AppSettingsReader settingReader = new AppSettingsReader();
string key = "Bhagwati";
if (useHasing)
{
MD5CryptoServiceProvider hashmd = new MD5CryptoServiceProvider();
keyArray = hashmd.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));
hashmd.Clear();
}
else
{
keyArray = UTF8Encoding.UTF8.GetBytes(key);
}
TripleDESCryptoServiceProvider tDes = new TripleDESCryptoServiceProvider();
tDes.Key = keyArray;
tDes.Mode = CipherMode.ECB;
tDes.Padding = PaddingMode.PKCS7;
ICryptoTransform cTransform = tDes.CreateDecryptor();
try
{
byte[] resultArray = cTransform.TransformFinalBlock(toDecryptArray, 0, toDecryptArray.Length);
tDes.Clear();
return UTF8Encoding.UTF8.GetString(resultArray,0,resultArray.Length);
}
catch (Exception ex)
{
throw ex;
}
}
}
}
回答by jbtule
Modern Examples of Symmetric Authenticated Encryption of a string.
字符串对称认证加密的现代示例。
The general best practice for symmetric encryption is to use Authenticated Encryption with Associated Data (AEAD), however this isn't a part of the standard .net crypto libraries. So the first example uses AES256and then HMAC256, a two step Encrypt then MAC, which requires more overhead and more keys.
对称加密的一般最佳实践是使用关联数据的身份验证加密 (AEAD)，但这不是标准 .net 加密库的一部分。所以第一个例子使用AES256然后HMAC256，两步Encrypt 然后 MAC，这需要更多的开销和更多的密钥。
The second example uses the simpler practice of AES256-GCMusing the open source Bouncy Castle (via nuget).
第二个示例使用 AES256- GCM的更简单实践，使用开源 Bouncy Castle（通过 nuget）。
Both examples have a main function that takes secret message string, key(s) and an optional non-secret payload and return and authenticated encrypted string optionally prepended with the non-secret data. Ideally you would use these with 256bit key(s) randomly generated see NewKey().
这两个示例都有一个 main 函数，该函数采用秘密消息字符串、密钥和可选的非秘密有效载荷，并返回和经过身份验证的加密字符串（可选地附加非秘密数据）。理想情况下，您可以将这些与随机生成的 256 位密钥一起使用，请参见NewKey()。
Both examples also have a helper methods that use a string password to generate the keys. These helper methods are provided as a convenience to match up with other examples, however they are far less securebecause the strength of the password is going to be far weaker than a 256 bit key.
这两个示例还具有使用字符串密码生成密钥的辅助方法。提供这些辅助方法是为了方便与其他示例进行匹配，但是它们的安全性要低得多，因为密码的强度将远弱于 256 位密钥。
Update:Added byte[]overloads, and only the Gisthas the full formatting with 4 spaces indent and api docs due to StackOverflow answer limits.
更新：添加了byte[]重载，由于 StackOverflow 答案限制，只有Gist具有完整的格式，缩进 4 个空格和 api 文档。
.NET Built-in Encrypt(AES)-Then-MAC(HMAC) [Gist]
.NET 内置加密 (AES)-Then-MAC(HMAC) [要点]
/*
* This work (Modern Encryption of a String C#, by James Tuley),
* identified by James Tuley, is free of known copyright restrictions.
* https://gist.github.com/4336842
* http://creativecommons.org/publicdomain/mark/1.0/
*/
using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
namespace Encryption
{
public static class AESThenHMAC
{
private static readonly RandomNumberGenerator Random = RandomNumberGenerator.Create();
//Preconfigured Encryption Parameters
public static readonly int BlockBitSize = 128;
public static readonly int KeyBitSize = 256;
//Preconfigured Password Key Derivation Parameters
public static readonly int SaltBitSize = 64;
public static readonly int Iterations = 10000;
public static readonly int MinPasswordLength = 12;
/// <summary>
/// Helper that generates a random key on each call.
/// </summary>
/// <returns></returns>
public static byte[] NewKey()
{
var key = new byte[KeyBitSize / 8];
Random.GetBytes(key);
return key;
}
/// <summary>
/// Simple Encryption (AES) then Authentication (HMAC) for a UTF8 Message.
/// </summary>
/// <param name="secretMessage">The secret message.</param>
/// <param name="cryptKey">The crypt key.</param>
/// <param name="authKey">The auth key.</param>
/// <param name="nonSecretPayload">(Optional) Non-Secret Payload.</param>
/// <returns>
/// Encrypted Message
/// </returns>
/// <exception cref="System.ArgumentException">Secret Message Required!;secretMessage</exception>
/// <remarks>
/// Adds overhead of (Optional-Payload + BlockSize(16) + Message-Padded-To-Blocksize + HMac-Tag(32)) * 1.33 Base64
/// </remarks>
public static string SimpleEncrypt(string secretMessage, byte[] cryptKey, byte[] authKey,
byte[] nonSecretPayload = null)
{
if (string.IsNullOrEmpty(secretMessage))
throw new ArgumentException("Secret Message Required!", "secretMessage");
var plainText = Encoding.UTF8.GetBytes(secretMessage);
var cipherText = SimpleEncrypt(plainText, cryptKey, authKey, nonSecretPayload);
return Convert.ToBase64String(cipherText);
}
/// <summary>
/// Simple Authentication (HMAC) then Decryption (AES) for a secrets UTF8 Message.
/// </summary>
/// <param name="encryptedMessage">The encrypted message.</param>
/// <param name="cryptKey">The crypt key.</param>
/// <param name="authKey">The auth key.</param>
/// <param name="nonSecretPayloadLength">Length of the non secret payload.</param>
/// <returns>
/// Decrypted Message
/// </returns>
/// <exception cref="System.ArgumentException">Encrypted Message Required!;encryptedMessage</exception>
public static string SimpleDecrypt(string encryptedMessage, byte[] cryptKey, byte[] authKey,
int nonSecretPayloadLength = 0)
{
if (string.IsNullOrWhiteSpace(encryptedMessage))
throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");
var cipherText = Convert.FromBase64String(encryptedMessage);
var plainText = SimpleDecrypt(cipherText, cryptKey, authKey, nonSecretPayloadLength);
return plainText == null ? null : Encoding.UTF8.GetString(plainText);
}
/// <summary>
/// Simple Encryption (AES) then Authentication (HMAC) of a UTF8 message
/// using Keys derived from a Password (PBKDF2).
/// </summary>
/// <param name="secretMessage">The secret message.</param>
/// <param name="password">The password.</param>
/// <param name="nonSecretPayload">The non secret payload.</param>
/// <returns>
/// Encrypted Message
/// </returns>
/// <exception cref="System.ArgumentException">password</exception>
/// <remarks>
/// Significantly less secure than using random binary keys.
/// Adds additional non secret payload for key generation parameters.
/// </remarks>
public static string SimpleEncryptWithPassword(string secretMessage, string password,
byte[] nonSecretPayload = null)
{
if (string.IsNullOrEmpty(secretMessage))
throw new ArgumentException("Secret Message Required!", "secretMessage");
var plainText = Encoding.UTF8.GetBytes(secretMessage);
var cipherText = SimpleEncryptWithPassword(plainText, password, nonSecretPayload);
return Convert.ToBase64String(cipherText);
}
/// <summary>
/// Simple Authentication (HMAC) and then Descryption (AES) of a UTF8 Message
/// using keys derived from a password (PBKDF2).
/// </summary>
/// <param name="encryptedMessage">The encrypted message.</param>
/// <param name="password">The password.</param>
/// <param name="nonSecretPayloadLength">Length of the non secret payload.</param>
/// <returns>
/// Decrypted Message
/// </returns>
/// <exception cref="System.ArgumentException">Encrypted Message Required!;encryptedMessage</exception>
/// <remarks>
/// Significantly less secure than using random binary keys.
/// </remarks>
public static string SimpleDecryptWithPassword(string encryptedMessage, string password,
int nonSecretPayloadLength = 0)
{
if (string.IsNullOrWhiteSpace(encryptedMessage))
throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");
var cipherText = Convert.FromBase64String(encryptedMessage);
var plainText = SimpleDecryptWithPassword(cipherText, password, nonSecretPayloadLength);
return plainText == null ? null : Encoding.UTF8.GetString(plainText);
}
public static byte[] SimpleEncrypt(byte[] secretMessage, byte[] cryptKey, byte[] authKey, byte[] nonSecretPayload = null)
{
//User Error Checks
if (cryptKey == null || cryptKey.Length != KeyBitSize / 8)
throw new ArgumentException(String.Format("Key needs to be {0} bit!", KeyBitSize), "cryptKey");
if (authKey == null || authKey.Length != KeyBitSize / 8)
throw new ArgumentException(String.Format("Key needs to be {0} bit!", KeyBitSize), "authKey");
if (secretMessage == null || secretMessage.Length < 1)
throw new ArgumentException("Secret Message Required!", "secretMessage");
//non-secret payload optional
nonSecretPayload = nonSecretPayload ?? new byte[] { };
byte[] cipherText;
byte[] iv;
using (var aes = new AesManaged
{
KeySize = KeyBitSize,
BlockSize = BlockBitSize,
Mode = CipherMode.CBC,
Padding = PaddingMode.PKCS7
})
{
//Use random IV
aes.GenerateIV();
iv = aes.IV;
using (var encrypter = aes.CreateEncryptor(cryptKey, iv))
using (var cipherStream = new MemoryStream())
{
using (var cryptoStream = new CryptoStream(cipherStream, encrypter, CryptoStreamMode.Write))
using (var binaryWriter = new BinaryWriter(cryptoStream))
{
//Encrypt Data
binaryWriter.Write(secretMessage);
}
cipherText = cipherStream.ToArray();
}
}
//Assemble encrypted message and add authentication
using (var hmac = new HMACSHA256(authKey))
using (var encryptedStream = new MemoryStream())
{
using (var binaryWriter = new BinaryWriter(encryptedStream))
{
//Prepend non-secret payload if any
binaryWriter.Write(nonSecretPayload);
//Prepend IV
binaryWriter.Write(iv);
//Write Ciphertext
binaryWriter.Write(cipherText);
binaryWriter.Flush();
//Authenticate all data
var tag = hmac.ComputeHash(encryptedStream.ToArray());
//Postpend tag
binaryWriter.Write(tag);
}
return encryptedStream.ToArray();
}
}
public static byte[] SimpleDecrypt(byte[] encryptedMessage, byte[] cryptKey, byte[] authKey, int nonSecretPayloadLength = 0)
{
//Basic Usage Error Checks
if (cryptKey == null || cryptKey.Length != KeyBitSize / 8)
throw new ArgumentException(String.Format("CryptKey needs to be {0} bit!", KeyBitSize), "cryptKey");
if (authKey == null || authKey.Length != KeyBitSize / 8)
throw new ArgumentException(String.Format("AuthKey needs to be {0} bit!", KeyBitSize), "authKey");
if (encryptedMessage == null || encryptedMessage.Length == 0)
throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");
using (var hmac = new HMACSHA256(authKey))
{
var sentTag = new byte[hmac.HashSize / 8];
//Calculate Tag
var calcTag = hmac.ComputeHash(encryptedMessage, 0, encryptedMessage.Length - sentTag.Length);
var ivLength = (BlockBitSize / 8);
//if message length is to small just return null
if (encryptedMessage.Length < sentTag.Length + nonSecretPayloadLength + ivLength)
return null;
//Grab Sent Tag
Array.Copy(encryptedMessage, encryptedMessage.Length - sentTag.Length, sentTag, 0, sentTag.Length);
//Compare Tag with constant time comparison
var compare = 0;
for (var i = 0; i < sentTag.Length; i++)
compare |= sentTag[i] ^ calcTag[i];
//if message doesn't authenticate return null
if (compare != 0)
return null;
using (var aes = new AesManaged
{
KeySize = KeyBitSize,
BlockSize = BlockBitSize,
Mode = CipherMode.CBC,
Padding = PaddingMode.PKCS7
})
{
//Grab IV from message
var iv = new byte[ivLength];
Array.Copy(encryptedMessage, nonSecretPayloadLength, iv, 0, iv.Length);
using (var decrypter = aes.CreateDecryptor(cryptKey, iv))
using (var plainTextStream = new MemoryStream())
{
using (var decrypterStream = new CryptoStream(plainTextStream, decrypter, CryptoStreamMode.Write))
using (var binaryWriter = new BinaryWriter(decrypterStream))
{
//Decrypt Cipher Text from Message
binaryWriter.Write(
encryptedMessage,
nonSecretPayloadLength + iv.Length,
encryptedMessage.Length - nonSecretPayloadLength - iv.Length - sentTag.Length
);
}
//Return Plain Text
return plainTextStream.ToArray();
}
}
}
}
public static byte[] SimpleEncryptWithPassword(byte[] secretMessage, string password, byte[] nonSecretPayload = null)
{
nonSecretPayload = nonSecretPayload ?? new byte[] {};
//User Error Checks
if (string.IsNullOrWhiteSpace(password) || password.Length < MinPasswordLength)
throw new ArgumentException(String.Format("Must have a password of at least {0} characters!", MinPasswordLength), "password");
if (secretMessage == null || secretMessage.Length ==0)
throw new ArgumentException("Secret Message Required!", "secretMessage");
var payload = new byte[((SaltBitSize / 8) * 2) + nonSecretPayload.Length];
Array.Copy(nonSecretPayload, payload, nonSecretPayload.Length);
int payloadIndex = nonSecretPayload.Length;
byte[] cryptKey;
byte[] authKey;
//Use Random Salt to prevent pre-generated weak password attacks.
using (var generator = new Rfc2898DeriveBytes(password, SaltBitSize / 8, Iterations))
{
var salt = generator.Salt;
//Generate Keys
cryptKey = generator.GetBytes(KeyBitSize / 8);
//Create Non Secret Payload
Array.Copy(salt, 0, payload, payloadIndex, salt.Length);
payloadIndex += salt.Length;
}
//Deriving separate key, might be less efficient than using HKDF,
//but now compatible with RNEncryptor which had a very similar wireformat and requires less code than HKDF.
using (var generator = new Rfc2898DeriveBytes(password, SaltBitSize / 8, Iterations))
{
var salt = generator.Salt;
//Generate Keys
authKey = generator.GetBytes(KeyBitSize / 8);
//Create Rest of Non Secret Payload
Array.Copy(salt, 0, payload, payloadIndex, salt.Length);
}
return SimpleEncrypt(secretMessage, cryptKey, authKey, payload);
}
public static byte[] SimpleDecryptWithPassword(byte[] encryptedMessage, string password, int nonSecretPayloadLength = 0)
{
//User Error Checks
if (string.IsNullOrWhiteSpace(password) || password.Length < MinPasswordLength)
throw new ArgumentException(String.Format("Must have a password of at least {0} characters!", MinPasswordLength), "password");
if (encryptedMessage == null || encryptedMessage.Length == 0)
throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");
var cryptSalt = new byte[SaltBitSize / 8];
var authSalt = new byte[SaltBitSize / 8];
//Grab Salt from Non-Secret Payload
Array.Copy(encryptedMessage, nonSecretPayloadLength, cryptSalt, 0, cryptSalt.Length);
Array.Copy(encryptedMessage, nonSecretPayloadLength + cryptSalt.Length, authSalt, 0, authSalt.Length);
byte[] cryptKey;
byte[] authKey;
//Generate crypt key
using (var generator = new Rfc2898DeriveBytes(password, cryptSalt, Iterations))
{
cryptKey = generator.GetBytes(KeyBitSize / 8);
}
//Generate auth key
using (var generator = new Rfc2898DeriveBytes(password, authSalt, Iterations))
{
authKey = generator.GetBytes(KeyBitSize / 8);
}
return SimpleDecrypt(encryptedMessage, cryptKey, authKey, cryptSalt.Length + authSalt.Length + nonSecretPayloadLength);
}
}
}
Bouncy Castle AES-GCM [Gist]
充气城堡 AES-GCM [要点]
/*
* This work (Modern Encryption of a String C#, by James Tuley),
* identified by James Tuley, is free of known copyright restrictions.
* https://gist.github.com/4336842
* http://creativecommons.org/publicdomain/mark/1.0/
*/
using System;
using System.IO;
using System.Text;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.Engines;
using Org.BouncyCastle.Crypto.Generators;
using Org.BouncyCastle.Crypto.Modes;
using Org.BouncyCastle.Crypto.Parameters;
using Org.BouncyCastle.Security;
namespace Encryption
{
public static class AESGCM
{
private static readonly SecureRandom Random = new SecureRandom();
//Preconfigured Encryption Parameters
public static readonly int NonceBitSize = 128;
public static readonly int MacBitSize = 128;
public static readonly int KeyBitSize = 256;
//Preconfigured Password Key Derivation Parameters
public static readonly int SaltBitSize = 128;
public static readonly int Iterations = 10000;
public static readonly int MinPasswordLength = 12;
/// <summary>
/// Helper that generates a random new key on each call.
/// </summary>
/// <returns></returns>
public static byte[] NewKey()
{
var key = new byte[KeyBitSize / 8];
Random.NextBytes(key);
return key;
}
/// <summary>
/// Simple Encryption And Authentication (AES-GCM) of a UTF8 string.
/// </summary>
/// <param name="secretMessage">The secret message.</param>
/// <param name="key">The key.</param>
/// <param name="nonSecretPayload">Optional non-secret payload.</param>
/// <returns>
/// Encrypted Message
/// </returns>
/// <exception cref="System.ArgumentException">Secret Message Required!;secretMessage</exception>
/// <remarks>
/// Adds overhead of (Optional-Payload + BlockSize(16) + Message + HMac-Tag(16)) * 1.33 Base64
/// </remarks>
public static string SimpleEncrypt(string secretMessage, byte[] key, byte[] nonSecretPayload = null)
{
if (string.IsNullOrEmpty(secretMessage))
throw new ArgumentException("Secret Message Required!", "secretMessage");
var plainText = Encoding.UTF8.GetBytes(secretMessage);
var cipherText = SimpleEncrypt(plainText, key, nonSecretPayload);
return Convert.ToBase64String(cipherText);
}
/// <summary>
/// Simple Decryption & Authentication (AES-GCM) of a UTF8 Message
/// </summary>
/// <param name="encryptedMessage">The encrypted message.</param>
/// <param name="key">The key.</param>
/// <param name="nonSecretPayloadLength">Length of the optional non-secret payload.</param>
/// <returns>Decrypted Message</returns>
public static string SimpleDecrypt(string encryptedMessage, byte[] key, int nonSecretPayloadLength = 0)
{
if (string.IsNullOrEmpty(encryptedMessage))
throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");
var cipherText = Convert.FromBase64String(encryptedMessage);
var plainText = SimpleDecrypt(cipherText, key, nonSecretPayloadLength);
return plainText == null ? null : Encoding.UTF8.GetString(plainText);
}
/// <summary>
/// Simple Encryption And Authentication (AES-GCM) of a UTF8 String
/// using key derived from a password (PBKDF2).
/// </summary>
/// <param name="secretMessage">The secret message.</param>
/// <param name="password">The password.</param>
/// <param name="nonSecretPayload">The non secret payload.</param>
/// <returns>
/// Encrypted Message
/// </returns>
/// <remarks>
/// Significantly less secure than using random binary keys.
/// Adds additional non secret payload for key generation parameters.
/// </remarks>
public static string SimpleEncryptWithPassword(string secretMessage, string password,
byte[] nonSecretPayload = null)
{
if (string.IsNullOrEmpty(secretMessage))
throw new ArgumentException("Secret Message Required!", "secretMessage");
var plainText = Encoding.UTF8.GetBytes(secretMessage);
var cipherText = SimpleEncryptWithPassword(plainText, password, nonSecretPayload);
return Convert.ToBase64String(cipherText);
}
/// <summary>
/// Simple Decryption and Authentication (AES-GCM) of a UTF8 message
/// using a key derived from a password (PBKDF2)
/// </summary>
/// <param name="encryptedMessage">The encrypted message.</param>
/// <param name="password">The password.</param>
/// <param name="nonSecretPayloadLength">Length of the non secret payload.</param>
/// <returns>
/// Decrypted Message
/// </returns>
/// <exception cref="System.ArgumentException">Encrypted Message Required!;encryptedMessage</exception>
/// <remarks>
/// Significantly less secure than using random binary keys.
/// </remarks>
public static string SimpleDecryptWithPassword(string encryptedMessage, string password,
int nonSecretPayloadLength = 0)
{
if (string.IsNullOrWhiteSpace(encryptedMessage))
throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");
var cipherText = Convert.FromBase64String(encryptedMessage);
var plainText = SimpleDecryptWithPassword(cipherText, password, nonSecretPayloadLength);
return plainText == null ? null : Encoding.UTF8.GetString(plainText);
}
public static byte[] SimpleEncrypt(byte[] secretMessage, byte[] key, byte[] nonSecretPayload = null)
{
//User Error Checks
if (key == null || key.Length != KeyBitSize / 8)
throw new ArgumentException(String.Format("Key needs to be {0} bit!", KeyBitSize), "key");
if (secretMessage == null || secretMessage.Length == 0)
throw new ArgumentException("Secret Message Required!", "secretMessage");
//Non-secret Payload Optional
nonSecretPayload = nonSecretPayload ?? new byte[] { };
//Using random nonce large enough not to repeat
var nonce = new byte[NonceBitSize / 8];
Random.NextBytes(nonce, 0, nonce.Length);
var cipher = new GcmBlockCipher(new AesFastEngine());
var parameters = new AeadParameters(new KeyParameter(key), MacBitSize, nonce, nonSecretPayload);
cipher.Init(true, parameters);
//Generate Cipher Text With Auth Tag
var cipherText = new byte[cipher.GetOutputSize(secretMessage.Length)];
var len = cipher.ProcessBytes(secretMessage, 0, secretMessage.Length, cipherText, 0);
cipher.DoFinal(cipherText, len);
//Assemble Message
using (var combinedStream = new MemoryStream())
{
using (var binaryWriter = new BinaryWriter(combinedStream))
{
//Prepend Authenticated Payload
binaryWriter.Write(nonSecretPayload);
//Prepend Nonce
binaryWriter.Write(nonce);
//Write Cipher Text
binaryWriter.Write(cipherText);
}
return combinedStream.ToArray();
}
}
public static byte[] SimpleDecrypt(byte[] encryptedMessage, byte[] key, int nonSecretPayloadLength = 0)
{
//User Error Checks
if (key == null || key.Length != KeyBitSize / 8)
throw new ArgumentException(String.Format("Key needs to be {0} bit!", KeyBitSize), "key");
if (encryptedMessage == null || encryptedMessage.Length == 0)
throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");
using (var cipherStream = new MemoryStream(encryptedMessage))
using (var cipherReader = new BinaryReader(cipherStream))
{
//Grab Payload
var nonSecretPayload = cipherReader.ReadBytes(nonSecretPayloadLength);
//Grab Nonce
var nonce = cipherReader.ReadBytes(NonceBitSize / 8);
var cipher = new GcmBlockCipher(new AesFastEngine());
var parameters = new AeadParameters(new KeyParameter(key), MacBitSize, nonce, nonSecretPayload);
cipher.Init(false, parameters);
//Decrypt Cipher Text
var cipherText = cipherReader.ReadBytes(encryptedMessage.Length - nonSecretPayloadLength - nonce.Length);
var plainText = new byte[cipher.GetOutputSize(cipherText.Length)];
try
{
var len = cipher.ProcessBytes(cipherText, 0, cipherText.Length, plainText, 0);
cipher.DoFinal(plainText, len);
}
catch (InvalidCipherTextException)
{
//Return null if it doesn't authenticate
return null;
}
return plainText;
}
}
public static byte[] SimpleEncryptWithPassword(byte[] secretMessage, string password, byte[] nonSecretPayload = null)
{
nonSecretPayload = nonSecretPayload ?? new byte[] {};
//User Error Checks
if (string.IsNullOrWhiteSpace(password) || password.Length < MinPasswordLength)
throw new ArgumentException(String.Format("Must have a password of at least {0} characters!", MinPasswordLength), "password");
if (secretMessage == null || secretMessage.Length == 0)
throw new ArgumentException("Secret Message Required!", "secretMessage");
var generator = new Pkcs5S2ParametersGenerator();
//Use Random Salt to minimize pre-generated weak password attacks.
var salt = new byte[SaltBitSize / 8];
Random.NextBytes(salt);
generator.Init(
PbeParametersGenerator.Pkcs5PasswordToBytes(password.ToCharArray()),
salt,
Iterations);
//Generate Key
var key = (KeyParameter)generator.GenerateDerivedMacParameters(KeyBitSize);
//Create Full Non Secret Payload
var payload = new byte[salt.Length + nonSecretPayload.Length];
Array.Copy(nonSecretPayload, payload, nonSecretPayload.Length);
Array.Copy(salt,0, payload,nonSecretPayload.Length, salt.Length);
return SimpleEncrypt(secretMessage, key.GetKey(), payload);
}
public static byte[] SimpleDecryptWithPassword(byte[] encryptedMessage, string password, int nonSecretPayloadLength = 0)
{
//User Error Checks
if (string.IsNullOrWhiteSpace(password) || password.Length < MinPasswordLength)
throw new ArgumentException(String.Format("Must have a password of at least {0} characters!", MinPasswordLength), "password");
if (encryptedMessage == null || encryptedMessage.Length == 0)
throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");
var generator = new Pkcs5S2ParametersGenerator();
//Grab Salt from Payload
var salt = new byte[SaltBitSize / 8];
Array.Copy(encryptedMessage, nonSecretPayloadLength, salt, 0, salt.Length);
generator.Init(
PbeParametersGenerator.Pkcs5PasswordToBytes(password.ToCharArray()),
salt,
Iterations);
//Generate Key
var key = (KeyParameter)generator.GenerateDerivedMacParameters(KeyBitSize);
return SimpleDecrypt(encryptedMessage, key.GetKey(), salt.Length + nonSecretPayloadLength);
}
}
}
回答by MAXE
I want to give you my contribute, with my code for AES Rfc2898DeriveBytes(herethe documentation) algorhytm, written in C# (.NET framework 4) and fully working also for limited platforms, as .NET Compact Framework for Windows Phone 7.0+ (not all platforms support every criptographic method of the .NET framework!).
我想给你我的贡献，我的 AES 代码Rfc2898DeriveBytes（这里是文档）algorhytm，用 C#（.NET 框架 4）编写，并且也完全适用于有限的平台，如 .NET Compact Framework for Windows Phone 7.0+（不是全部）平台支持 .NET 框架的所有脚本方法！）。
I hope this can help anyone!
我希望这可以帮助任何人！
using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
public static class Crypto
{
private static readonly byte[] IVa = new byte[] { 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x11, 0x11, 0x12, 0x13, 0x14, 0x0e, 0x16, 0x17 };
public static string Encrypt(this string text, string salt)
{
try
{
using (Aes aes = new AesManaged())
{
Rfc2898DeriveBytes deriveBytes = new Rfc2898DeriveBytes(Encoding.UTF8.GetString(IVa, 0, IVa.Length), Encoding.UTF8.GetBytes(salt));
aes.Key = deriveBytes.GetBytes(128 / 8);
aes.IV = aes.Key;
using (MemoryStream encryptionStream = new MemoryStream())
{
using (CryptoStream encrypt = new CryptoStream(encryptionStream, aes.CreateEncryptor(), CryptoStreamMode.Write))
{
byte[] cleanText = Encoding.UTF8.GetBytes(text);
encrypt.Write(cleanText, 0, cleanText.Length);
encrypt.FlushFinalBlock();
}
byte[] encryptedData = encryptionStream.ToArray();
string encryptedText = Convert.ToBase64String(encryptedData);
return encryptedText;
}
}
}
catch
{
return String.Empty;
}
}
public static string Decrypt(this string text, string salt)
{
try
{
using (Aes aes = new AesManaged())
{
Rfc2898DeriveBytes deriveBytes = new Rfc2898DeriveBytes(Encoding.UTF8.GetString(IVa, 0, IVa.Length), Encoding.UTF8.GetBytes(salt));
aes.Key = deriveBytes.GetBytes(128 / 8);
aes.IV = aes.Key;
using (MemoryStream decryptionStream = new MemoryStream())
{
using (CryptoStream decrypt = new CryptoStream(decryptionStream, aes.CreateDecryptor(), CryptoStreamMode.Write))
{
byte[] encryptedData = Convert.FromBase64String(text);
decrypt.Write(encryptedData, 0, encryptedData.Length);
decrypt.Flush();
}
byte[] decryptedData = decryptionStream.ToArray();
string decryptedText = Encoding.UTF8.GetString(decryptedData, 0, decryptedData.Length);
return decryptedText;
}
}
}
catch
{
return String.Empty;
}
}
}
}
回答by nerdybeardo
BouncyCastleis a great Crypto library for .NET, it's available as a Nugetpackage for install into your projects. I like it a lot more than what's currently available in the System.Security.Cryptography library. It gives you a lot more options in terms of available algorithms, and provides more modes for those algorithms.
BouncyCastle是一个很棒的 .NET 加密库，它可以作为Nuget包安装到您的项目中。我比 System.Security.Cryptography 库中目前可用的更喜欢它。它在可用算法方面为您提供了更多选择，并为这些算法提供了更多模式。
This is an example of an implementation of TwoFish, which was written by Bruce Schneier(hero to all us paranoid people out there). It's a symmetric algorithm like the Rijndael (aka AES). It was one of the three finalists for the AES standard and sibling to another famous algorithm written by Bruce Schneier called BlowFish.
这是TwoFish实现的一个例子，它是由Bruce Schneier（我们所有偏执狂的英雄）编写的。它是一种类似于 Rijndael（又名 AES）的对称算法。它是 AES 标准的三名决赛选手之一，也是 Bruce Schneier 编写的另一个著名算法 BlowFish 的兄弟。
First thing with bouncycastle is to create an encryptor class, this will make it easier to implement other block ciphers within the library. The following encryptor class takes in a generic argument T where T implements IBlockCipher and has a default constructor.
bouncycastle 的第一件事是创建一个加密器类，这将使在库中实现其他分组密码更容易。以下加密器类采用通用参数 T，其中 T 实现 IBlockCipher 并具有默认构造函数。
UPDATE:Due to popular demand I have decided to implement generating a random IV as well as include an HMAC into this class. Although from a style perspective this goes against the SOLID principle of single responsibility, because of the nature of what this class does I reniged. This class will now take two generic parameters, one for the cipher and one for the digest. It automatically generates the IV using RNGCryptoServiceProvider to provide good RNG entropy, and allows you to use whatever digest algorithm you want from BouncyCastle to generate the MAC.
更新：由于受欢迎的需求，我决定实现生成随机 IV 并将 HMAC 包含到此类中。虽然从风格的角度来看，这违背了单一职责的 SOLID 原则，但由于这个类的性质，我拒绝了。这个类现在将采用两个通用参数，一个用于密码，一个用于摘要。它使用 RNGCryptoServiceProvider 自动生成 IV 以提供良好的 RNG 熵，并允许您使用 BouncyCastle 中您想要的任何摘要算法来生成 MAC。
using System;
using System.Security.Cryptography;
using System.Text;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.Macs;
using Org.BouncyCastle.Crypto.Modes;
using Org.BouncyCastle.Crypto.Paddings;
using Org.BouncyCastle.Crypto.Parameters;
public sealed class Encryptor<TBlockCipher, TDigest>
where TBlockCipher : IBlockCipher, new()
where TDigest : IDigest, new()
{
private Encoding encoding;
private IBlockCipher blockCipher;
private BufferedBlockCipher cipher;
private HMac mac;
private byte[] key;
public Encryptor(Encoding encoding, byte[] key, byte[] macKey)
{
this.encoding = encoding;
this.key = key;
this.Init(key, macKey, new Pkcs7Padding());
}
public Encryptor(Encoding encoding, byte[] key, byte[] macKey, IBlockCipherPadding padding)
{
this.encoding = encoding;
this.key = key;
this.Init(key, macKey, padding);
}
private void Init(byte[] key, byte[] macKey, IBlockCipherPadding padding)
{
this.blockCipher = new CbcBlockCipher(new TBlockCipher());
this.cipher = new PaddedBufferedBlockCipher(this.blockCipher, padding);
this.mac = new HMac(new TDigest());
this.mac.Init(new KeyParameter(macKey));
}
public string Encrypt(string plain)
{
return Convert.ToBase64String(EncryptBytes(plain));
}
public byte[] EncryptBytes(string plain)
{
byte[] input = this.encoding.GetBytes(plain);
var iv = this.GenerateIV();
var cipher = this.BouncyCastleCrypto(true, input, new ParametersWithIV(new KeyParameter(key), iv));
byte[] message = CombineArrays(iv, cipher);
this.mac.Reset();
this.mac.BlockUpdate(message, 0, message.Length);
byte[] digest = new byte[this.mac.GetUnderlyingDigest().GetDigestSize()];
this.mac.DoFinal(digest, 0);
var result = CombineArrays(digest, message);
return result;
}
public byte[] DecryptBytes(byte[] bytes)
{
// split the digest into component parts
var digest = new byte[this.mac.GetUnderlyingDigest().GetDigestSize()];
var message = new byte[bytes.Length - digest.Length];
var iv = new byte[this.blockCipher.GetBlockSize()];
var cipher = new byte[message.Length - iv.Length];
Buffer.BlockCopy(bytes, 0, digest, 0, digest.Length);
Buffer.BlockCopy(bytes, digest.Length, message, 0, message.Length);
if (!IsValidHMac(digest, message))
{
throw new CryptoException();
}
Buffer.BlockCopy(message, 0, iv, 0, iv.Length);
Buffer.BlockCopy(message, iv.Length, cipher, 0, cipher.Length);
byte[] result = this.BouncyCastleCrypto(false, cipher, new ParametersWithIV(new KeyParameter(key), iv));
return result;
}
public string Decrypt(byte[] bytes)
{
return this.encoding.GetString(DecryptBytes(bytes));
}
public string Decrypt(string cipher)
{
return this.Decrypt(Convert.FromBase64String(cipher));
}
private bool IsValidHMac(byte[] digest, byte[] message)
{
this.mac.Reset();
this.mac.BlockUpdate(message, 0, message.Length);
byte[] computed = new byte[this.mac.GetUnderlyingDigest().GetDigestSize()];
this.mac.DoFinal(computed, 0);
return AreEqual(digest,computed);
}
private static bool AreEqual(byte [] digest, byte[] computed)
{
if(digest.Length != computed.Length)
{
return false;
}
int result = 0;
for (int i = 0; i < digest.Length; i++)
{
// compute equality of all bytes before returning.
// helps prevent timing attacks:
// https://codahale.com/a-lesson-in-timing-attacks/
result |= digest[i] ^ computed[i];
}
return result == 0;
}
private byte[] BouncyCastleCrypto(bool forEncrypt, byte[] input, ICipherParameters parameters)
{
try
{
cipher.Init(forEncrypt, parameters);
return this.cipher.DoFinal(input);
}
catch (CryptoException)
{
throw;
}
}
private byte[] GenerateIV()
{
using (var provider = new RNGCryptoServiceProvider())
{
// 1st block
byte[] result = new byte[this.blockCipher.GetBlockSize()];
provider.GetBytes(result);
return result;
}
}
private static byte[] CombineArrays(byte[] source1, byte[] source2)
{
byte[] result = new byte[source1.Length + source2.Length];
Buffer.BlockCopy(source1, 0, result, 0, source1.Length);
Buffer.BlockCopy(source2, 0, result, source1.Length, source2.Length);
return result;
}
}
Next just call the encrypt and decrypt methods on the new class, here's the example using twofish:
接下来只需在新类上调用加密和解密方法，这是使用 twofish 的示例：
var encrypt = new Encryptor<TwofishEngine, Sha1Digest>(Encoding.UTF8, key, hmacKey);
string cipher = encrypt.Encrypt("TEST");
string plainText = encrypt.Decrypt(cipher);
It's just as easy to substitute another block cipher like TripleDES:
替换另一个块密码（如 TripleDES）同样容易：
var des = new Encryptor<DesEdeEngine, Sha1Digest>(Encoding.UTF8, key, hmacKey);
string cipher = des.Encrypt("TEST");
string plainText = des.Decrypt(cipher);
Finally if you want to use AES with SHA256 HMAC you can do the following:
最后，如果您想将 AES 与 SHA256 HMAC 一起使用，您可以执行以下操作：
var aes = new Encryptor<AesEngine, Sha256Digest>(Encoding.UTF8, key, hmacKey);
cipher = aes.Encrypt("TEST");
plainText = aes.Decrypt(cipher);
The hardest part about encryption actually deals with the keys and not the algorithms. You'll have to think about where you store your keys, and if you have to, how you exchange them. These algorithms have all withstood the test of time, and are extremely hard to break. Someone who wants to steal information from you isn't going to spend eternity doing cryptanalysis on your messages, they're going to try to figure out what or where your key is. So #1 choose your keys wisely, #2 store them in a safe place, if you use a web.config and IIS then you can encrypt parts of the the web.config, and finally if you have to exchange keys make sure that your protocol for exchanging the key is secure.
加密最难的部分实际上是处理密钥而不是算法。您必须考虑将密钥存储在哪里，如果必须，您还需要考虑如何交换它们。这些算法都经受住了时间的考验，极难破解。想要从您那里窃取信息的人不会永远对您的消息进行密码分析，他们会试图找出您的密钥是什么或在哪里。因此，#1 明智地选择您的密钥，#2 将它们存储在安全的地方，如果您使用 web.config 和 IIS，那么您可以加密 web.config 的一部分，最后，如果您必须交换密钥，请确保您的用于交换密钥的协议是安全的。
Update 2Changed compare method to mitigate against timing attacks. See more info here http://codahale.com/a-lesson-in-timing-attacks/. Also updated to default to PKCS7 padding and added new constructor to allow end user the ability to choose which padding they would like to use. Thanks @CodesInChaos for the suggestions.
更新 2更改了比较方法以减轻计时攻击。在此处查看更多信息http://codahale.com/a-lesson-in-timing-attacks/。还更新为默认为 PKCS7 填充并添加了新的构造函数以允许最终用户选择他们想要使用的填充。感谢@CodesInChaos 的建议。
回答by mattmanser
If you are using ASP.Net you can now use built in functionality in .Net 4.0 onwards.
如果您使用的是 ASP.Net，您现在可以使用 .Net 4.0 以后的内置功能。
System.Web.Security.MachineKey
.Net 4.5 has MachineKey.Protect()and MachineKey.Unprotect().
.Net 4.5 具有MachineKey.Protect()和MachineKey.Unprotect().
.Net 4.0 has MachineKey.Encode()and MachineKey.Decode(). You should just set the MachineKeyProtection to 'All'.
.Net 4.0 具有MachineKey.Encode()和MachineKey.Decode(). 您应该将 MachineKeyProtection 设置为“全部”。
Outside of ASP.Net this class seems to generate a new key with every app restart so doesn't work. With a quick peek in ILSpy it looks to me like it generates its own defaults if the appropriate app.settings are missing. So you may actually be able to set it up outside ASP.Net.
在 ASP.Net 之外，此类似乎在每次应用程序重新启动时生成一个新密钥，因此不起作用。在 ILSpy 中快速浏览一下，在我看来，如果缺少相应的 app.settings，它会生成自己的默认值。所以你实际上可以在 ASP.Net 之外设置它。
I haven't been able to find a non-ASP.Net equivalent outside the System.Web namespace.
我无法在 System.Web 命名空间之外找到非 ASP.Net 等效项。
回答by Catto
This is the class that was placed here by Brett. However I made a slight edit since I was receiving the error 'Invalid length for a Base-64 char array' when using it for URL strings to encrypt and decrypt.
这是布雷特安排在这里的课程。但是，由于在将 URL 字符串用于加密和解密时收到错误“Base-64 字符数组的长度无效”，我进行了轻微的编辑。
public class CryptoURL
{
private static byte[] _salt = Encoding.ASCII.GetBytes("Catto_Salt_Enter_Any_Value99");
/// <summary>
/// Encrypt the given string using AES. The string can be decrypted using
/// DecryptStringAES(). The sharedSecret parameters must match.
/// The SharedSecret for the Password Reset that is used is in the next line
/// string sharedSecret = "OneUpSharedSecret9";
/// </summary>
/// <param name="plainText">The text to encrypt.</param>
/// <param name="sharedSecret">A password used to generate a key for encryption.</param>
public static string EncryptString(string plainText, string sharedSecret)
{
if (string.IsNullOrEmpty(plainText))
throw new ArgumentNullException("plainText");
if (string.IsNullOrEmpty(sharedSecret))
throw new ArgumentNullException("sharedSecret");
string outStr = null; // Encrypted string to return
RijndaelManaged aesAlg = null; // RijndaelManaged object used to encrypt the data.
try
{
// generate the key from the shared secret and the salt
Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(sharedSecret, _salt);
// Create a RijndaelManaged object
aesAlg = new RijndaelManaged();
aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);
// Create a decryptor to perform the stream transform.
ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);
// Create the streams used for encryption.
using (MemoryStream msEncrypt = new MemoryStream())
{
// prepend the IV
msEncrypt.Write(BitConverter.GetBytes(aesAlg.IV.Length), 0, sizeof(int));
msEncrypt.Write(aesAlg.IV, 0, aesAlg.IV.Length);
using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
{
using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
{
//Write all data to the stream.
swEncrypt.Write(plainText);
}
}
outStr = HttpServerUtility.UrlTokenEncode(msEncrypt.ToArray());
//outStr = Convert.ToBase64String(msEncrypt.ToArray());
// you may need to add a reference. right click reference in solution explorer => "add Reference" => .NET tab => select "System.Web"
}
}
finally
{
// Clear the RijndaelManaged object.
if (aesAlg != null)
aesAlg.Clear();
}
// Return the encrypted bytes from the memory stream.
return outStr;
}
/// <summary>
/// Decrypt the given string. Assumes the string was encrypted using
/// EncryptStringAES(), using an identical sharedSecret.
/// </summary>
/// <param name="cipherText">The text to decrypt.</param>
/// <param name="sharedSecret">A password used to generate a key for decryption.</param>
public static string DecryptString(string cipherText, string sharedSecret)
{
if (string.IsNullOrEmpty(cipherText))
throw new ArgumentNullException("cipherText");
if (string.IsNullOrEmpty(sharedSecret))
throw new ArgumentNullException("sharedSecret");
// Declare the RijndaelManaged object
// used to decrypt the data.
RijndaelManaged aesAlg = null;
// Declare the string used to hold
// the decrypted text.
string plaintext = null;
byte[] inputByteArray;
try
{
// generate the key from the shared secret and the salt
Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(sharedSecret, _salt);
// Create the streams used for decryption.
//byte[] bytes = Convert.FromBase64String(cipherText);
inputByteArray = HttpServerUtility.UrlTokenDecode(cipherText);
using (MemoryStream msDecrypt = new MemoryStream(inputByteArray))
{
// Create a RijndaelManaged object
// with the specified key and IV.
aesAlg = new RijndaelManaged();
aesAlg.Key = key.GetBytes(aesAlg.KeySize / 8);
// Get the initialization vector from the encrypted stream
aesAlg.IV = ReadByteArray(msDecrypt);
// Create a decrytor to perform the stream transform.
ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);
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();
}
}
}
catch (System.Exception ex)
{
return "ERROR";
//throw ex;
}
finally
{
// Clear the RijndaelManaged object.
if (aesAlg != null)
aesAlg.Clear();
}
return plaintext;
}
static string ConvertStringArrayToString(string[] array)
{
//
// Concatenate all the elements into a StringBuilder.
//
StringBuilder builder = new StringBuilder();
foreach (string value in array)
{
builder.Append(value);
builder.Append('.');
}
return builder.ToString();
}
private static byte[] ReadByteArray(Stream s)
{
byte[] rawLength = new byte[sizeof(int)];
if (s.Read(rawLength, 0, rawLength.Length) != rawLength.Length)
{
throw new SystemException("Stream did not contain properly formatted byte array");
}
byte[] buffer = new byte[BitConverter.ToInt32(rawLength, 0)];
if (s.Read(buffer, 0, buffer.Length) != buffer.Length)
{
throw new SystemException("Did not read byte array properly");
}
return buffer;
}
}
回答by KarthikManoharan
using System;
using System.Collections.Generic;
using System.Text;
using System.Text.RegularExpressions; // This is for password validation
using System.Security.Cryptography;
using System.Configuration; // This is where the hash functions reside
namespace BullyTracker.Common
{
public class HashEncryption
{
//public string GenerateHashvalue(string thisPassword)
//{
// MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
// byte[] tmpSource;
// byte[] tmpHash;
// tmpSource = ASCIIEncoding.ASCII.GetBytes(thisPassword); // Turn password into byte array
// tmpHash = md5.ComputeHash(tmpSource);
// StringBuilder sOutput = new StringBuilder(tmpHash.Length);
// for (int i = 0; i < tmpHash.Length; i++)
// {
// sOutput.Append(tmpHash[i].ToString("X2")); // X2 formats to hexadecimal
// }
// return sOutput.ToString();
//}
//public Boolean VerifyHashPassword(string thisPassword, string thisHash)
//{
// Boolean IsValid = false;
// string tmpHash = GenerateHashvalue(thisPassword); // Call the routine on user input
// if (tmpHash == thisHash) IsValid = true; // Compare to previously generated hash
// return IsValid;
//}
public string GenerateHashvalue(string toEncrypt, bool useHashing)
{
byte[] keyArray;
byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(toEncrypt);
System.Configuration.AppSettingsReader settingsReader = new AppSettingsReader();
// Get the key from config file
string key = (string)settingsReader.GetValue("SecurityKey", typeof(String));
//System.Windows.Forms.MessageBox.Show(key);
if (useHashing)
{
MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));
hashmd5.Clear();
}
else
keyArray = UTF8Encoding.UTF8.GetBytes(key);
TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
tdes.Key = keyArray;
tdes.Mode = CipherMode.ECB;
tdes.Padding = PaddingMode.PKCS7;
ICryptoTransform cTransform = tdes.CreateEncryptor();
byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
tdes.Clear();
return Convert.ToBase64String(resultArray, 0, resultArray.Length);
}
/// <summary>
/// DeCrypt a string using dual encryption method. Return a DeCrypted clear string
/// </summary>
/// <param name="cipherString">encrypted string</param>
/// <param name="useHashing">Did you use hashing to encrypt this data? pass true is yes</param>
/// <returns></returns>
public string Decrypt(string cipherString, bool useHashing)
{
byte[] keyArray;
byte[] toEncryptArray = Convert.FromBase64String(cipherString);
System.Configuration.AppSettingsReader settingsReader = new AppSettingsReader();
//Get your key from config file to open the lock!
string key = (string)settingsReader.GetValue("SecurityKey", typeof(String));
if (useHashing)
{
MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
keyArray = hashmd5.ComputeHash(UTF8Encoding.UTF8.GetBytes(key));
hashmd5.Clear();
}
else
keyArray = UTF8Encoding.UTF8.GetBytes(key);
TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
tdes.Key = keyArray;
tdes.Mode = CipherMode.ECB;
tdes.Padding = PaddingMode.PKCS7;
ICryptoTransform cTransform = tdes.CreateDecryptor();
byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
tdes.Clear();
return UTF8Encoding.UTF8.GetString(resultArray);
}
}
}
回答by user3556387
for simplicity i made for myself this function that i use for non crypto purposes : replace "yourpassphrase" with your password ...
为简单起见，我为自己制作了这个用于非加密目的的功能：用您的密码替换“您的密码”...
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Security.Cryptography;
using System.IO;
namespace My
{
public class strCrypto
{
// This constant string is used as a "salt" value for the PasswordDeriveBytes function calls.
// This size of the IV (in bytes) must = (keysize / 8). Default keysize is 256, so the IV must be
// 32 bytes long. Using a 16 character string here gives us 32 bytes when converted to a byte array.
private const string initVector = "r5dm5fgm24mfhfku";
private const string passPhrase = "yourpassphrase"; // email password encryption password
// This constant is used to determine the keysize of the encryption algorithm.
private const int keysize = 256;
public static string encryptString(string plainText)
{
//if the plaintext is empty or null string just return an empty string
if (plainText == "" || plainText == null )
{
return "";
}
byte[] initVectorBytes = Encoding.UTF8.GetBytes(initVector);
byte[] plainTextBytes = Encoding.UTF8.GetBytes(plainText);
PasswordDeriveBytes password = new PasswordDeriveBytes(passPhrase, null);
byte[] keyBytes = password.GetBytes(keysize / 8);
RijndaelManaged symmetricKey = new RijndaelManaged();
symmetricKey.Mode = CipherMode.CBC;
ICryptoTransform encryptor = symmetricKey.CreateEncryptor(keyBytes, initVectorBytes);
MemoryStream memoryStream = new MemoryStream();
CryptoStream cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write);
cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
cryptoStream.FlushFinalBlock();
byte[] cipherTextBytes = memoryStream.ToArray();
memoryStream.Close();
cryptoStream.Close();
return Convert.ToBase64String(cipherTextBytes);
}
public static string decryptString(string cipherText)
{
//if the ciphertext is empty or null string just return an empty string
if (cipherText == "" || cipherText == null )
{
return "";
}
byte[] initVectorBytes = Encoding.ASCII.GetBytes(initVector);
byte[] cipherTextBytes = Convert.FromBase64String(cipherText);
PasswordDeriveBytes password = new PasswordDeriveBytes(passPhrase, null);
byte[] keyBytes = password.GetBytes(keysize / 8);
RijndaelManaged symmetricKey = new RijndaelManaged();
symmetricKey.Mode = CipherMode.CBC;
ICryptoTransform decryptor = symmetricKey.CreateDecryptor(keyBytes, initVectorBytes);
MemoryStream memoryStream = new MemoryStream(cipherTextBytes);
CryptoStream cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read);
byte[] plainTextBytes = new byte[cipherTextBytes.Length];
int decryptedByteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length);
memoryStream.Close();
cryptoStream.Close();
return Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount);
}
}
}
}
