RSA加密解密及RSA签名和验证及证书

公钥是给别人的
1. 发送密文使用公钥加密
2. 验证签名使用公钥验证
私钥是自己保留的
1. 接受密文使用私钥解密
2. 发送签名使用私钥签名
上述过程逆转是不行的，比如使用私钥加密，使用公钥解密是不行的
证书的制作参考自使用X.509数字证书加密解密实务（一）-- 证书的获得和管理
1. 打开VS开发命令，输入下面的命令：
2. ```
makecert -sr CurrentUser -ss My -n CN=MyTestCert -sky exchange -pe
```
从证书中读取私钥和公钥：

/// <summary>   
        /// 根据私钥证书得到证书实体，得到实体后可以根据其公钥和私钥进行加解密   
        /// 加解密函数使用DEncrypt的RSACryption类   
        /// </summary>   
        /// <param name="pfxFileName"></param>   
        /// <param name="password"></param>   
        /// <returns></returns>   
        public static X509Certificate2 GetCertificateFromPfxFile(string pfxFileName,
            string password)
        {
            try
            {
                return new X509Certificate2(pfxFileName, password, X509KeyStorageFlags.Exportable);
            }
            catch (Exception e)
            {
                return null;
            }
        }

View Code

var cer=  RSACryption.GetCertificateFromPfxFile(@"D:\my.pfx", "123456");
            tbPrivateKey.Text = cer.PrivateKey.ToXmlString(true);
            tbPublicKey.Text = cer.PublicKey.Key.ToXmlString(false);

View Code

完整测试代码：

WPF前端：

<Window x:Class="Security.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:Security"
        mc:Ignorable="d"
        Title="MainWindow" Height="700" Width="1200">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition Height="auto"></RowDefinition>
        </Grid.RowDefinitions>
        <StackPanel Margin="3" Orientation="Horizontal" HorizontalAlignment="Left">
            <Button Margin="3" Name="GenerateKeys" Click="GenerateKeys_Click">生成Key</Button>
            <Button Margin="3" Name="Encrypt" Click="Encrypt_Click">公钥加密</Button>
            <Button Margin="3" Name="Decrypt" Click="Decrypt_Click">私钥解密</Button>
            <Button Margin="3" Name="GetHash" Click="GetHash_Click">获取Hash</Button>
            <Button Margin="3" Name="Sign" Click="Sign_Click">私钥签名</Button>
            <Button Margin="3" Name="ValidateSign" Click="ValidateSign_Click">签名验证</Button>
            <Button Margin="3" Name="InputPfx" Click="InputPfx_Click">导入证书</Button>
            <Button Margin="3" Name="EcryptByPrivateKey" Click="EcryptByPrivateKey_Click">私钥加密</Button>
            <Button Margin="3" Name="DcryptByPrivateKey" Click="DcryptByPrivateKey_Click">公钥解密</Button>
        </StackPanel>
        <StackPanel Grid.Row="1" Margin="3">
            <TextBlock Margin="3">公钥：</TextBlock>
            <TextBox Name="tbPublicKey" TextWrapping="Wrap" MinLines="2"  Margin="3"></TextBox>
        </StackPanel>
        <StackPanel Grid.Row="2" Margin="3">
            <TextBlock Margin="3">私钥：</TextBlock>
            <TextBox Name="tbPrivateKey" TextWrapping="Wrap" MinLines="5" Margin="3"></TextBox>
        </StackPanel>
        <StackPanel Grid.Row="3" Margin="3">
            <TextBlock Margin="3">待加密内容：</TextBlock>
            <TextBox Name="tbContent" TextWrapping="Wrap" MinLines="3" Margin="3">i am cypher</TextBox>
        </StackPanel>
        <StackPanel Grid.Row="4" Margin="3">
            <TextBlock Margin="3">公钥加密后内容：</TextBlock>
            <TextBox Name="tbEncryptContent" TextWrapping="Wrap" MinLines="2" Margin="3"></TextBox>
        </StackPanel>
        <StackPanel Grid.Row="5" Margin="3">
            <TextBlock Margin="3">私钥解密后内容：</TextBlock>
            <TextBox Name="tbDecryptContent" TextWrapping="Wrap"  Margin="3"></TextBox>
        </StackPanel>
        <StackPanel Grid.Row="6" Margin="3">
            <TextBlock Margin="3">Hash：</TextBlock>
            <TextBox Name="tbHash"  Margin="3"></TextBox>
        </StackPanel>
        <StackPanel Grid.Row="7" Margin="3">
            <TextBlock Margin="3">私钥签名后内容：</TextBlock>
            <TextBox Name="tbSign" TextWrapping="Wrap" MinLines="2" Margin="3"></TextBox>
        </StackPanel>
        <StackPanel Grid.Row="8" Margin="3">
            <TextBlock Margin="3">公钥签名验证：</TextBlock>
            <TextBox Name="tbValidateSign" TextWrapping="Wrap"  Margin="3"></TextBox>
        </StackPanel>
    </Grid>
</Window>

View Code

后端：

public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void GenerateKeys_Click(object sender, RoutedEventArgs e)
        {
            string privateKey = "";
            string publicKey = "";
            RSACryption.GenerateKey(out privateKey, out publicKey);
            tbPrivateKey.Text = privateKey;
            tbPublicKey.Text = publicKey;
        }

        private void Encrypt_Click(object sender, RoutedEventArgs e)
        {
            tbEncryptContent.Text = RSACryption.RSAEncrypt(tbPublicKey.Text, tbContent.Text);
        }

        private void Decrypt_Click(object sender, RoutedEventArgs e)
        {
            tbDecryptContent.Text = RSACryption.RSADecrypt(tbPrivateKey.Text, tbEncryptContent.Text);
        }

        private void Sign_Click(object sender, RoutedEventArgs e)
        {
            tbSign.Text = RSACryption.GetSignature(tbPrivateKey.Text, tbHash.Text);
        }

        private void GetHash_Click(object sender, RoutedEventArgs e)
        {
            tbHash.Text = RSACryption.GetHash(tbContent.Text);
        }

        private void ValidateSign_Click(object sender, RoutedEventArgs e)
        {
            tbValidateSign.Text = RSACryption.ValidateSignature(tbPublicKey.Text, tbHash.Text, tbSign.Text).ToString();
        }

        private void InputPfx_Click(object sender, RoutedEventArgs e)
        {
            var cer=  RSACryption.GetCertificateFromPfxFile(@"D:\my.pfx", "123456");
            tbPrivateKey.Text = cer.PrivateKey.ToXmlString(true);
            tbPublicKey.Text = cer.PublicKey.Key.ToXmlString(false);
        }

        private void EcryptByPrivateKey_Click(object sender, RoutedEventArgs e)
        {
            tbEncryptContent.Text = RSACryption.RSAEncrypt(tbPrivateKey.Text, tbContent.Text);
        }

        private void DcryptByPrivateKey_Click(object sender, RoutedEventArgs e)
        {
            tbDecryptContent.Text = RSACryption.RSADecrypt(tbPublicKey.Text, tbEncryptContent.Text);
        }
    }

View Code

附上转自飛雲若雪的代码：

class RSACryption
{        
    #region RSA 加密解密

    #region RSA 的密钥产生
    /// <summary>
    /// RSA产生密钥
    /// </summary>
    /// <param name="xmlKeys">私钥</param>
    /// <param name="xmlPublicKey">公钥</param>
    public void RSAKey(out string xmlKeys, out string xmlPublicKey)
    {
        try
        {
            System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
            xmlKeys = rsa.ToXmlString(true);
            xmlPublicKey = rsa.ToXmlString(false);
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
    #endregion

    #region RSA加密函数
    //############################################################################## 
    //RSA 方式加密 
    //KEY必须是XML的形式,返回的是字符串 
    //该加密方式有长度限制的！
    //############################################################################## 
       
    /// <summary>
    /// RSA的加密函数
    /// </summary>
    /// <param name="xmlPublicKey">公钥</param>
    /// <param name="encryptString">待加密的字符串</param>
    /// <returns></returns>
    public string RSAEncrypt(string xmlPublicKey, string encryptString)
    {
        try
        {
            byte[] PlainTextBArray;
            byte[] CypherTextBArray;
            string Result;
            System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
            rsa.FromXmlString(xmlPublicKey);
            PlainTextBArray = (new UnicodeEncoding()).GetBytes(encryptString);
            CypherTextBArray = rsa.Encrypt(PlainTextBArray, false);
            Result = Convert.ToBase64String(CypherTextBArray);
            return Result;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }        
    /// <summary>
    /// RSA的加密函数 
    /// </summary>
    /// <param name="xmlPublicKey">公钥</param>
    /// <param name="EncryptString">待加密的字节数组</param>
    /// <returns></returns>
    public string RSAEncrypt(string xmlPublicKey, byte[] EncryptString)
    {
        try
        {
            byte[] CypherTextBArray;
            string Result;
            System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
            rsa.FromXmlString(xmlPublicKey);
            CypherTextBArray = rsa.Encrypt(EncryptString, false);
            Result = Convert.ToBase64String(CypherTextBArray);
            return Result;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
    #endregion

    #region RSA的解密函数        
    /// <summary>
    /// RSA的解密函数
    /// </summary>
    /// <param name="xmlPrivateKey">私钥</param>
    /// <param name="decryptString">待解密的字符串</param>
    /// <returns></returns>
    public string RSADecrypt(string xmlPrivateKey, string decryptString)
    {
        try
        {
            byte[] PlainTextBArray;
            byte[] DypherTextBArray;
            string Result;
            System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
            rsa.FromXmlString(xmlPrivateKey);
            PlainTextBArray = Convert.FromBase64String(decryptString);
            DypherTextBArray = rsa.Decrypt(PlainTextBArray, false);
            Result = (new UnicodeEncoding()).GetString(DypherTextBArray);
            return Result;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }        
    /// <summary>
    /// RSA的解密函数 
    /// </summary>
    /// <param name="xmlPrivateKey">私钥</param>
    /// <param name="DecryptString">待解密的字节数组</param>
    /// <returns></returns>
    public string RSADecrypt(string xmlPrivateKey, byte[] DecryptString)
    {
        try
        {
            byte[] DypherTextBArray;
            string Result;
            System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
            rsa.FromXmlString(xmlPrivateKey);
            DypherTextBArray = rsa.Decrypt(DecryptString, false);
            Result = (new UnicodeEncoding()).GetString(DypherTextBArray);
            return Result;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
    #endregion

    #endregion

    #region RSA数字签名

    #region 获取Hash描述表        
    /// <summary>
    /// 获取Hash描述表
    /// </summary>
    /// <param name="strSource">待签名的字符串</param>
    /// <param name="HashData">Hash描述</param>
    /// <returns></returns>
    public bool GetHash(string strSource, ref byte[] HashData)
    {
        try
        {               
            byte[] Buffer;
            System.Security.Cryptography.HashAlgorithm MD5 = System.Security.Cryptography.HashAlgorithm.Create("MD5");
            Buffer = System.Text.Encoding.GetEncoding("GB2312").GetBytes(strSource);
            HashData = MD5.ComputeHash(Buffer);
            return true;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

    /// <summary>
    /// 获取Hash描述表
    /// </summary>
    /// <param name="strSource">待签名的字符串</param>
    /// <param name="strHashData">Hash描述</param>
    /// <returns></returns>
    public bool GetHash(string strSource, ref string strHashData)
    {
        try
        {
            //从字符串中取得Hash描述 
            byte[] Buffer;
            byte[] HashData;
            System.Security.Cryptography.HashAlgorithm MD5 = System.Security.Cryptography.HashAlgorithm.Create("MD5");
            Buffer = System.Text.Encoding.GetEncoding("GB2312").GetBytes(strSource);
            HashData = MD5.ComputeHash(Buffer);
            strHashData = Convert.ToBase64String(HashData);
            return true;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

    /// <summary>
    /// 获取Hash描述表
    /// </summary>
    /// <param name="objFile">待签名的文件</param>
    /// <param name="HashData">Hash描述</param>
    /// <returns></returns>
    public bool GetHash(System.IO.FileStream objFile, ref byte[] HashData)
    {
        try
        {
            //从文件中取得Hash描述 
            System.Security.Cryptography.HashAlgorithm MD5 = System.Security.Cryptography.HashAlgorithm.Create("MD5");
            HashData = MD5.ComputeHash(objFile);
            objFile.Close();
            return true;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

    /// <summary>
    /// 获取Hash描述表
    /// </summary>
    /// <param name="objFile">待签名的文件</param>
    /// <param name="strHashData">Hash描述</param>
    /// <returns></returns>
    public bool GetHash(System.IO.FileStream objFile, ref string strHashData)
    {
        try
        {
            //从文件中取得Hash描述 
            byte[] HashData;
            System.Security.Cryptography.HashAlgorithm MD5 = System.Security.Cryptography.HashAlgorithm.Create("MD5");
            HashData = MD5.ComputeHash(objFile);
            objFile.Close();
            strHashData = Convert.ToBase64String(HashData);
            return true;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
    #endregion

    #region RSA签名
    /// <summary>
    /// RSA签名
    /// </summary>
    /// <param name="strKeyPrivate">私钥</param>
    /// <param name="HashbyteSignature">待签名Hash描述</param>
    /// <param name="EncryptedSignatureData">签名后的结果</param>
    /// <returns></returns>
    public bool SignatureFormatter(string strKeyPrivate, byte[] HashbyteSignature, ref byte[] EncryptedSignatureData)
    {
        try
        {
            System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider();

            RSA.FromXmlString(strKeyPrivate);
            System.Security.Cryptography.RSAPKCS1SignatureFormatter RSAFormatter = new System.Security.Cryptography.RSAPKCS1SignatureFormatter(RSA);
            //设置签名的算法为MD5 
            RSAFormatter.SetHashAlgorithm("MD5");
            //执行签名 
            EncryptedSignatureData = RSAFormatter.CreateSignature(HashbyteSignature);
            return true;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

    /// <summary>
    /// RSA签名
    /// </summary>
    /// <param name="strKeyPrivate">私钥</param>
    /// <param name="HashbyteSignature">待签名Hash描述</param>
    /// <param name="m_strEncryptedSignatureData">签名后的结果</param>
    /// <returns></returns>
    public bool SignatureFormatter(string strKeyPrivate, byte[] HashbyteSignature, ref string strEncryptedSignatureData)
    {
        try
        {
            byte[] EncryptedSignatureData;
            System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider();
            RSA.FromXmlString(strKeyPrivate);
            System.Security.Cryptography.RSAPKCS1SignatureFormatter RSAFormatter = new System.Security.Cryptography.RSAPKCS1SignatureFormatter(RSA);
            //设置签名的算法为MD5 
            RSAFormatter.SetHashAlgorithm("MD5");
            //执行签名 
            EncryptedSignatureData = RSAFormatter.CreateSignature(HashbyteSignature);
            strEncryptedSignatureData = Convert.ToBase64String(EncryptedSignatureData);
            return true;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

    /// <summary>
    /// RSA签名
    /// </summary>
    /// <param name="strKeyPrivate">私钥</param>
    /// <param name="strHashbyteSignature">待签名Hash描述</param>
    /// <param name="EncryptedSignatureData">签名后的结果</param>
    /// <returns></returns>
    public bool SignatureFormatter(string strKeyPrivate, string strHashbyteSignature, ref byte[] EncryptedSignatureData)
    {
        try
        {
            byte[] HashbyteSignature;

            HashbyteSignature = Convert.FromBase64String(strHashbyteSignature);
            System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider();

            RSA.FromXmlString(strKeyPrivate);
            System.Security.Cryptography.RSAPKCS1SignatureFormatter RSAFormatter = new System.Security.Cryptography.RSAPKCS1SignatureFormatter(RSA);
            //设置签名的算法为MD5 
            RSAFormatter.SetHashAlgorithm("MD5");
            //执行签名 
            EncryptedSignatureData = RSAFormatter.CreateSignature(HashbyteSignature);

            return true;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

    /// <summary>
    /// RSA签名
    /// </summary>
    /// <param name="strKeyPrivate">私钥</param>
    /// <param name="strHashbyteSignature">待签名Hash描述</param>
    /// <param name="strEncryptedSignatureData">签名后的结果</param>
    /// <returns></returns>
    public bool SignatureFormatter(string strKeyPrivate, string strHashbyteSignature, ref string strEncryptedSignatureData)
    {
        try
        {
            byte[] HashbyteSignature;
            byte[] EncryptedSignatureData;
            HashbyteSignature = Convert.FromBase64String(strHashbyteSignature);
            System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider();
            RSA.FromXmlString(strKeyPrivate);
            System.Security.Cryptography.RSAPKCS1SignatureFormatter RSAFormatter = new System.Security.Cryptography.RSAPKCS1SignatureFormatter(RSA);
            //设置签名的算法为MD5 
            RSAFormatter.SetHashAlgorithm("MD5");
            //执行签名 
            EncryptedSignatureData = RSAFormatter.CreateSignature(HashbyteSignature);
            strEncryptedSignatureData = Convert.ToBase64String(EncryptedSignatureData);
            return true;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
    #endregion

    #region RSA 签名验证
    /// <summary>
    /// RSA签名验证
    /// </summary>
    /// <param name="strKeyPublic">公钥</param>
    /// <param name="HashbyteDeformatter">Hash描述</param>
    /// <param name="DeformatterData">签名后的结果</param>
    /// <returns></returns>
    public bool SignatureDeformatter(string strKeyPublic, byte[] HashbyteDeformatter, byte[] DeformatterData)
    {
        try
        {
            System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider();
            RSA.FromXmlString(strKeyPublic);
            System.Security.Cryptography.RSAPKCS1SignatureDeformatter RSADeformatter = new System.Security.Cryptography.RSAPKCS1SignatureDeformatter(RSA);
            //指定解密的时候HASH算法为MD5 
            RSADeformatter.SetHashAlgorithm("MD5");
            if (RSADeformatter.VerifySignature(HashbyteDeformatter, DeformatterData))
            {
                return true;
            }
            else
            {
                return false;
            }
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
    /// <summary>
    /// RSA签名验证
    /// </summary>
    /// <param name="strKeyPublic">公钥</param>
    /// <param name="strHashbyteDeformatter">Hash描述</param>
    /// <param name="DeformatterData">签名后的结果</param>
    /// <returns></returns>
    public bool SignatureDeformatter(string strKeyPublic, string strHashbyteDeformatter, byte[] DeformatterData)
    {
        try
        {
            byte[] HashbyteDeformatter;
            HashbyteDeformatter = Convert.FromBase64String(strHashbyteDeformatter);
            System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider();
            RSA.FromXmlString(strKeyPublic);
            System.Security.Cryptography.RSAPKCS1SignatureDeformatter RSADeformatter = new System.Security.Cryptography.RSAPKCS1SignatureDeformatter(RSA);
            //指定解密的时候HASH算法为MD5 
            RSADeformatter.SetHashAlgorithm("MD5");
            if (RSADeformatter.VerifySignature(HashbyteDeformatter, DeformatterData))
            {
                return true;
            }
            else
            {
                return false;
            }
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
    /// <summary>
    /// RSA签名验证
    /// </summary>
    /// <param name="strKeyPublic">公钥</param>
    /// <param name="HashbyteDeformatter">Hash描述</param>
    /// <param name="strDeformatterData">签名后的结果</param>
    /// <returns></returns>
    public bool SignatureDeformatter(string strKeyPublic, byte[] HashbyteDeformatter, string strDeformatterData)
    {
        try
        {
            byte[] DeformatterData;
            System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider();
            RSA.FromXmlString(strKeyPublic);
            System.Security.Cryptography.RSAPKCS1SignatureDeformatter RSADeformatter = new System.Security.Cryptography.RSAPKCS1SignatureDeformatter(RSA);
            //指定解密的时候HASH算法为MD5 
            RSADeformatter.SetHashAlgorithm("MD5");
            DeformatterData = Convert.FromBase64String(strDeformatterData);
            if (RSADeformatter.VerifySignature(HashbyteDeformatter, DeformatterData))
            {
                return true;
            }
            else
            {
                return false;
            }
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
    /// <summary>
    /// RSA签名验证
    /// </summary>
    /// <param name="strKeyPublic">公钥</param>
    /// <param name="strHashbyteDeformatter">Hash描述</param>
    /// <param name="strDeformatterData">签名后的结果</param>
    /// <returns></returns>
    public bool SignatureDeformatter(string strKeyPublic, string strHashbyteDeformatter, string strDeformatterData)
    {
        try
        {
            byte[] DeformatterData;
            byte[] HashbyteDeformatter;
            HashbyteDeformatter = Convert.FromBase64String(strHashbyteDeformatter);
            System.Security.Cryptography.RSACryptoServiceProvider RSA = new System.Security.Cryptography.RSACryptoServiceProvider();
            RSA.FromXmlString(strKeyPublic);
            System.Security.Cryptography.RSAPKCS1SignatureDeformatter RSADeformatter = new System.Security.Cryptography.RSAPKCS1SignatureDeformatter(RSA);
            //指定解密的时候HASH算法为MD5 
            RSADeformatter.SetHashAlgorithm("MD5");
            DeformatterData = Convert.FromBase64String(strDeformatterData);
            if (RSADeformatter.VerifySignature(HashbyteDeformatter, DeformatterData))
            {
                return true;
            }
            else
            {
                return false;
            }
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
    #endregion

    #endregion 

}