RSA加密算法是一种非对称加密算法。在公钥加密标准和电子商业中RSA被广泛使用。RSA是1977年由罗纳德•李维斯特（Ron Rivest）、阿迪•萨莫尔（Adi Shamir）和伦纳德•阿德曼（Leonard Adleman）一起提出的。当时他们三人都在麻省理工学院工作。RSA就是他们三人姓氏开头字母拼在一起组成的。.Net的推出，我们能够利用.Net Framework中的类提供的加密服务来保证数据安全。目前应用较为广泛的加密方法是使用RSA算法进行加密。在.Net Framework中与RSA加密算法相关的类主要有两个：RSA 类和RSACryptoServiceProvider 类。按照MSDN的说法RSA 类是“表示 RSA 算法的所有实现均从中继承的基类”，而RSACryptoServiceProvider 类是“使用加密服务提供程序 (CSP) 提供的 RSA 算法的实现执行不对称加密和解密”。另外，“表示 RSA 算法的标准参数”的RSAParameters 结构也是很重要的，它保存了RSA算法的参数。
这里具体讲述一下在C#中如何使用框架提供的RSA算法来对我们的信息加密、签名、验证签名、解密的这个几个步骤的实现
代码
using System.Security.Cryptography;using System.Management;using Microsoft.Win32;/// <summary>/// 生成公私钥/// </summary>/// <param name="PrivateKeyPath"></param>/// <param name="PublicKeyPath"></param>
public void RSAKey(string PrivateKeyPath, string PublicKeyPath)
{
try{
RSACryptoServiceProvider provider
= new RSACryptoServiceProvider();this.CreatePrivateKeyXML(PrivateKeyPath, provider.ToXmlString(true));this.CreatePublicKeyXML(PublicKeyPath, provider.ToXmlString(false));}
catch (Exception exception){
throw exception;}
}
/// <summary>/// 对原始数据进行MD5加密/// </summary>/// <param name="m_strSource">待加密数据</param>/// <returns>返回机密后的数据</returns>{
HashAlgorithm algorithm
= HashAlgorithm.Create("MD5");byte[] bytes = Encoding.GetEncoding("GB2312").GetBytes(m_strSource);byte[] inArray = algorithm.ComputeHash(bytes);return Convert.ToBase64String(inArray);}
/// <summary>/// RSA加密/// </summary>/// <param name="xmlPublicKey">公钥</param>/// <param name="m_strEncryptString">MD5加密后的数据</param>/// <returns>RSA公钥加密后的数据</returns>{
string str2;try{
RSACryptoServiceProvider provider
= new RSACryptoServiceProvider();provider.FromXmlString(xmlPublicKey);
byte[] bytes = new UnicodeEncoding().GetBytes(m_strEncryptString);str2
= Convert.ToBase64String(provider.Encrypt(bytes, false));}
catch (Exception exception){
throw exception;}
return str2;}
/// <summary>/// RSA解密/// </summary>/// <param name="xmlPrivateKey">私钥</param>/// <param name="m_strDecryptString">待解密的数据</param>/// <returns>解密后的结果</returns>{
string str2;try{
RSACryptoServiceProvider provider
= new RSACryptoServiceProvider();provider.FromXmlString(xmlPrivateKey);
byte[] rgb = Convert.FromBase64String(m_strDecryptString);byte[] buffer2 = provider.Decrypt(rgb, false);str2
= new UnicodeEncoding().GetString(buffer2);}
catch (Exception exception){
throw exception;}
return str2;}
/// <summary>/// 对MD5加密后的密文进行签名/// </summary>/// <param name="p_strKeyPrivate">私钥</param>/// <param name="m_strHashbyteSignature">MD5加密后的密文</param>/// <returns></returns>{
byte[] rgbHash = Convert.FromBase64String(m_strHashbyteSignature);RSACryptoServiceProvider key
= new RSACryptoServiceProvider();key.FromXmlString(p_strKeyPrivate);
RSAPKCS1SignatureFormatter formatter
= new RSAPKCS1SignatureFormatter(key);formatter.SetHashAlgorithm(
"MD5");byte[] inArray = formatter.CreateSignature(rgbHash);return Convert.ToBase64String(inArray);}
/// <summary>/// 签名验证/// </summary>/// <param name="p_strKeyPublic">公钥</param>/// <param name="p_strHashbyteDeformatter">待验证的用户名</param>/// <param name="p_strDeformatterData">注册码</param>/// <returns></returns>{
try{
byte[] rgbHash = Convert.FromBase64String(p_strHashbyteDeformatter);RSACryptoServiceProvider key
= new RSACryptoServiceProvider();key.FromXmlString(p_strKeyPublic);
RSAPKCS1SignatureDeformatter deformatter
= new RSAPKCS1SignatureDeformatter(key);deformatter.SetHashAlgorithm(
"MD5");byte[] rgbSignature = Convert.FromBase64String(p_strDeformatterData);if (deformatter.VerifySignature(rgbHash, rgbSignature)){
return true;}
return false;}
catch{
return false;}
}
/// <summary>/// 获取硬盘ID/// </summary>/// <returns>硬盘ID</returns>{
string HDInfo = "";ManagementClass cimobject1
= new ManagementClass("Win32_DiskDrive");ManagementObjectCollection moc1
= cimobject1.GetInstances();foreach (ManagementObject mo in moc1){
HDInfo
= (string)mo.Properties["Model"].Value;}
return HDInfo;}
/// <summary>/// 读注册表中指定键的值/// </summary>/// <param name="key">键名</param>/// <returns>返回键值</returns>{
string temp = "";try{
RegistryKey myKey
= Registry.LocalMachine;RegistryKey subKey
= myKey.OpenSubKey(@"SOFTWARE\JX\Register");temp
= subKey.GetValue(key).ToString();subKey.Close();
myKey.Close();
return temp;}
catch (Exception){
throw;//可能没有此注册项;}
/// <summary>/// 创建注册表中指定的键和值/// </summary>/// <param name="key">键名</param>/// <param name="value">键值</param>{
try{
RegistryKey rootKey
= Registry.LocalMachine.CreateSubKey(@"SOFTWARE\JX\Register");rootKey.SetValue(key, value);
rootKey.Close();
}
catch (Exception){
throw;}
}
/// <summary>/// 创建公钥文件/// </summary>/// <param name="path"></param>/// <param name="publickey"></param>{
try{
FileStream publickeyxml
= new FileStream(path, FileMode.Create);StreamWriter sw
= new StreamWriter(publickeyxml);sw.WriteLine(publickey);
sw.Close();
publickeyxml.Close();
}
catch{
throw;}
}
/// <summary>/// 创建私钥文件/// </summary>/// <param name="path"></param>/// <param name="privatekey"></param>{
try{
FileStream privatekeyxml
= new FileStream(path, FileMode.Create);StreamWriter sw
= new StreamWriter(privatekeyxml);sw.WriteLine(privatekey);
sw.Close();
privatekeyxml.Close();
}
catch{
throw;}
}
/// <summary>/// 读取公钥/// </summary>/// <param name="path"></param>/// <returns></returns>{
StreamReader reader
= new StreamReader(path);string publickey = reader.ReadToEnd();reader.Close();
return publickey;}
/// <summary>/// 读取私钥/// </summary>/// <param name="path"></param>/// <returns></returns>{
StreamReader reader
= new StreamReader(path);string privatekey = reader.ReadToEnd();reader.Close();
return privatekey;}
/// <summary>/// 初始化注册表，程序运行时调用，在调用之前更新公钥xml/// </summary>/// <param name="path">公钥路径</param>{
Registry.LocalMachine.CreateSubKey(
@"SOFTWARE\JX\Register");Random ra
= new Random();string publickey = this.ReadPublicKey(path);if (Registry.LocalMachine.OpenSubKey(@"SOFTWARE\JX\Register").ValueCount <= 0){
this.WriteReg("RegisterRandom", ra.Next(1,100000).ToString());this.WriteReg("RegisterPublicKey", publickey);}
else{
this.WriteReg("RegisterPublicKey", publickey);}
}
如果是要对发送的消息进行加密和解密，加密时用公钥，解密时用私钥，即使密文被窃取也无法破解。
如果是要对软件进行注册，生成注册码，则服务端将用户的硬盘号用私钥加密，客户端用公钥解密，解密后将客户端的硬盘号进行MD5加密，将得到的结果和解密后的结果进行比较，如果相同，说明是注册用户，否则为非注册用户。
本文来自CSDN博客，转载请标明出处：http://blog.csdn.net/llwinnner/archive/2009/03/21/4011936.aspx
此内容由惯性聚合(RSS阅读器)自动聚合整理，仅供阅读参考。 原文来自 — 版权归原作者所有。