如何在c#中加密和解密字符串?
当前回答
using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
public class Program
{
public static void Main()
{
var key = Encoding.UTF8.GetBytes("SUkbqO2ycDo7QwpR25kfgmC7f8CoyrZy");
var data = Encoding.UTF8.GetBytes("testData");
//Encrypt data
var encrypted = CryptoHelper.EncryptData(data,key);
//Decrypt data
var decrypted = CryptoHelper.DecryptData(encrypted,key);
//Display result
Console.WriteLine(Encoding.UTF8.GetString(decrypted));
}
}
public static class CryptoHelper
{
public static byte[] EncryptData(byte[] data, byte[] key)
{
using (var aesAlg = Aes.Create())
{
aesAlg.Mode = CipherMode.CBC;
using (var encryptor = aesAlg.CreateEncryptor(key, aesAlg.IV))
{
using (var msEncrypt = new MemoryStream())
{
msEncrypt.Write(aesAlg.IV, 0, aesAlg.IV.Length);
using (var csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
csEncrypt.Write(data, 0, data.Length);
return msEncrypt.ToArray();
}
}
}
}
public static byte[] DecryptData(byte[] encrypted, byte[] key)
{
var iv = new byte[16];
Buffer.BlockCopy(encrypted, 0, iv, 0, iv.Length);
using (var aesAlg = Aes.Create())
{
aesAlg.Mode = CipherMode.CBC;
using (var decryptor = aesAlg.CreateDecryptor(key, iv))
{
using (var msDecrypt = new MemoryStream(encrypted, iv.Length, encrypted.Length - iv.Length))
{
using (var csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
{
using (var resultStream = new MemoryStream())
{
csDecrypt.CopyTo(resultStream);
return resultStream.ToArray();
}
}
}
}
}
}
}
其他回答
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;
}
}
}
}
下面是一个使用RSA的例子。
重要:使用RSA加密KeySize - MinimumPadding加密的数据大小是有限制的。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)
用RSA密钥替换your_rsa_key。
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));
更多信息，请访问MSDN - RSACryptoServiceProvider
用于AES-GCM加密的BouncyCastle的替代方案是libsodium-net。它包装了libsodium C库。一个很好的优点是它在cpu中使用AES-NI扩展进行非常快速的加密。缺点是，如果CPU没有扩展，它根本无法工作。软件没有退路。
我想给你我的贡献，与我的代码AES Rfc2898DeriveBytes(这里的文档)算法，写在c#(。NET框架4)，并且完全适用于有限的平台，如Windows Phone 7.0+的.NET紧凑框架(不是所有平台都支持.NET框架的每一种编码方法!)
我希望这能帮助到任何人!
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;
}
}
}
}
一个安全散列数据的好算法是BCrypt:
除了加入盐来抵御彩虹桌的攻击， Bcrypt是一个自适应函数:随着时间的推移，迭代计数可以 增加使它变慢，所以它仍然抵抗蛮力 搜索攻击，即使增加计算能力。
BCrypt有一个很好的。net实现，也可以作为NuGet包使用。
