RSA加密（前端js）和MD5加密(后台)同时使用实例

新公司对于用户密码保护十分严密，采用了两种加密方式，

例如修改密码时，仅加密流程如下

首先在前端使用RSA加密方式对密码进行一次加密，数据传到后台， 然后RSA解密,最后存入数据库前，再进行一次MD5盐值加密

功能实现如下

项目中引用一个js文件  文件名  jsencrypt.min.js

下载地址：https://pan.baidu.com/s/1Nmb183-5-x8NmVu83ftnYg 提取码: w3a7

前台加密部分：

var encrypt = new JSEncrypt();
encrypt.setPublicKey("此处为RSA公钥");

var myPassword="123456";

 myPassword= encodeURI(myPassword).replace(/\+/g, '%2B');

此时即得到加密处理过的密码

后台处理部分：

注意添加命名空间 using System.Security.Cryptography;

private string Encryption(string myPassword, string key)
{

//RSA解密
string privateKey = "此处为RSA私钥";
RSACreatKey RsaCreate = new RSACreatKey();
RSACryptoServiceProvider rsaCryptoServiceProvider = RsaCreate.CreateRsaKeyPair(privateKey);
byte[] rc = rsaCryptoServiceProvider.Decrypt(Convert.FromBase64String(myPassword.Replace("%2B", "+")), false);

//MD5+盐值加密后返回
return MD5password.MD5Encoding(Encoding.UTF8.GetString(rc), key);

}

RSA具体解密过程 即 RSACreatKey 类中CreateRsaKeyPair方法

public RSACryptoServiceProvider CreateRsaKeyPair(string privateKey)
{
  var privateKeyBits = System.Convert.FromBase64String(privateKey);
  var RSA = new RSACryptoServiceProvider();
  var RSAparams = new RSAParameters();
  using (BinaryReader binr = new BinaryReader(new MemoryStream(privateKeyBits)))
  {
    byte bt = 0;
    ushort twobytes = 0;
    twobytes = binr.ReadUInt16();
    if (twobytes == 0x8130)
      binr.ReadByte();
    else if (twobytes == 0x8230)
      binr.ReadInt16();
    else
      throw new Exception("Unexpected value read binr.ReadUInt16()");
    twobytes = binr.ReadUInt16();
    if (twobytes != 0x0102)
      throw new Exception("Unexpected version");
    bt = binr.ReadByte();
    if (bt != 0x00)
      throw new Exception("Unexpected value read binr.ReadByte()");
    RSAparams.Modulus = binr.ReadBytes(GetIntegerSize(binr));
    RSAparams.Exponent = binr.ReadBytes(GetIntegerSize(binr));
    RSAparams.D = binr.ReadBytes(GetIntegerSize(binr));
    RSAparams.P = binr.ReadBytes(GetIntegerSize(binr));
    RSAparams.Q = binr.ReadBytes(GetIntegerSize(binr));
    RSAparams.DP = binr.ReadBytes(GetIntegerSize(binr));
    RSAparams.DQ = binr.ReadBytes(GetIntegerSize(binr));
    RSAparams.InverseQ = binr.ReadBytes(GetIntegerSize(binr));
  }
  RSA.ImportParameters(RSAparams);
  return RSA;
}

private int GetIntegerSize(BinaryReader binr)
{
  byte bt = 0;
  byte lowbyte = 0x00;
  byte highbyte = 0x00;
  int count = 0;
  bt = binr.ReadByte();
  if (bt != 0x02)
    return 0;
  bt = binr.ReadByte();
  if (bt == 0x81)
    count = binr.ReadByte();
  else
    if (bt == 0x82)
    {
      highbyte = binr.ReadByte();
      lowbyte = binr.ReadByte();
      byte[] modint = { lowbyte, highbyte, 0x00, 0x00 };
      count = BitConverter.ToInt32(modint, 0);
    }
    else
    {
      count = bt;
    }
  while (binr.ReadByte() == 0x00)
  {
    count -= 1;
  }
  binr.BaseStream.Seek(-1, SeekOrigin.Current);
  return count;
}

MD5盐值加密过程  //即MD5password类中的MD5Encoding方法

//MD5加密

public static string MD5Encoding(string psw) 
{
  MD5 md5 = MD5.Create();
  byte[] bs = Encoding.UTF8.GetBytes(psw);
  byte[] hs = md5.ComputeHash(bs);
  StringBuilder stb = new StringBuilder();
  foreach (byte b in hs)
  {
    // 以十六进制格式格式化
    stb.Append(b.ToString("x2"));
  }
  return stb.ToString();
}

//MD5盐值加密
public static string MD5Encoding(string rawPass, object salt)
{
  if (salt == null) return rawPass;
  return MD5Encoding(rawPass + "{" + salt.ToString() + "}");
}