RSA前臺js加密,後臺C#解密

1、需求:

     爲了安全,項目中前臺登錄用的密碼須要加密傳到後臺，後臺c#解密登錄密碼。

2、解決方案

      採用非對稱加密算法RSA來達到目的，前臺登錄頁面一加載便發送一次ajax請求獲取後臺產生的公鑰，用於前臺加密，用戶點擊登錄時出發加密過程並提交加密的數據到後臺，後臺C#語言採用已封裝好的RSA算法工具進行密碼解密。

     如下爲c#RSA算法加密代碼：

        private static RSAParameters rsap = new RSAParameters() {
            Modulus = Convert.FromBase64String(@"sB6+4rtO2sYeIZ8kJGGM647PIm+dJkwvSPNWcQ01D2cwPjIGV2c41h39FjYuzgAKzrIFjSvuBpG4y/PFEHuN+
                                                 LackSt6MU7qcbs7lzub8V97XZ5fddPaq/GWXo9mrIMMFDMW7z88WrukLGTvwkqySPBemc22rjua1uTR3azae7U="),
            Exponent = Convert.FromBase64String(@"AQAB"),
            P = Convert.FromBase64String(@"8yUCFVCufr3z2LDAwHaUO4r3na3WZqhAb3J7aXv/rj9UEXQWwZoG8IbUzV2fUhMXjnFXyrRSqywWdpxeE6oLWw=="),
            Q = Convert.FromBase64String(@"uW6NlpzkBl4Do7K4RUDCsZ9uiVqnU0cbm7JVuygWJts+pu1ho5s0auUekQy5al6p4xifjWIcCsLvPxsLuWISLw=="),
            DP = Convert.FromBase64String(@"rDsf0ad4I3E8hNcXgn28nLzgj8Hu6ILwOcGXZ+4c+/oB++cGo5cOqVxo6xwRWhsKCa2B6aV4FaZCNzymazl9lw=="),
            DQ = Convert.FromBase64String(@"dVVT+FKMIs9IZEPJP+DrkTM94WHgcNyUxp9Aii2iXrHqYfvhBYJG18Dk54lypbECtLU2+GJ1NgYFFxxI/ePldw=="),
            InverseQ = Convert.FromBase64String(@"z8qRY0+yyfZFNFPMtlTumpYyCXUbK+GpWnFp2hOyTABya/h7g4DCRE6iO9UZKgW4paB5K75mJwdBgVib5NgFiQ=="),
            D = Convert.FromBase64String(@"W1ZWoLeLWaJNlho2YDfHIZLakX1Y/reb/jVUqySyU96sAlVnPITn0QOUcaR/+Y3EDRX+EwypUPbZ48v0c2vgYDHwIb
                                           rIbsEyN+vHoUNJ319R5kUZ8Wlfw/w6/6BSclqbWQ8OdSj1cKwx/EEJh4iipqJ8HBTsmoT0anQHP/jdybE=")
        };

        private static string RSAEncrypt(string publicKey, string content) {

            RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(1024);// RSACryptoServiceProvider();

            rsa.ImportParameters(rsap);//導入公鑰

            byte[] result = rsa.Encrypt(Encoding.UTF8.GetBytes(content), false);

            return Convert.ToBase64String(result);
        }

        private static string RSADecrypt(string privateKey, string content) {

            RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(1024);

            rsa.ImportParameters(rsap);

            var result = rsa.Decrypt(Convert.FromBase64String(content), false);

            return Encoding.UTF8.GetString(result);
        }

  後臺傳到前臺的公鑰信息爲：

  rsap.Exponent.HexEncode()；

  rsap.Modulus.HexEncode()；

  HexEncode()爲字節數組類型靜態擴展,只爲每一個字節轉化爲對應的16進制，代碼以下：

public static string ToHexEncode(this byte[] bytes) {
            return BitConverter.ToString(bytes).Replace("-", string.Empty);
        }

 採用上面靜態對象rsap，經HexEncode傳到前臺的公鑰信息爲：

1.010001
2.B01EBEE2BB4EDAC61E219F2424618CEB8ECF226F9D264C2F48F356710D350F67303E3206576738D61DFD16362ECE000ACEB2058D2BEE0691B8CBF3C5107B
  8DF8B69C912B7A314EEA71BB3B973B9BF15F7B5D9E5F75D3DAABF1965E8F66AC830C143316EF3F3C5ABBA42C64EFC24AB248F05E99CDB6AE3B9AD6E4D1DD
  ACDA7BB5

前臺js加密，從網上搜颳了RSA的js實現，頁面需依次加入三個js文件：BigInt.js，Barrett.js，RSA.js,後面附上這三個js庫。好比加密zjt，js代碼以下：

setMaxDigits(130);
var key = new RSAKeyPair('010001', "", 'B01EBEE2BB4EDAC61E219F2424618CEB8ECF226F9D264C2F48F356710D350F67303E3206576738D61DFD163
62ECE000ACEB2058D2BEE0691B8CBF3C5107B8DF8B69C912B7A314EEA71BB3B973B9BF15F7B5D9E5F75D3DAABF1965E8F66AC830C143316EF3F3C5ABBA42C64
EFC24AB248F05E99CDB6AE3B9AD6E4D1DDACDA7BB5');
var res = encryptedString(key,'zjt')

 獲得res爲加密結果，用於會傳到後臺，res結果爲：

9839c4f8cf40e5cd30be61a1e215c571424fca76108aacecc5ca45f9cdb6c207f4477eff32d41799babe915fd8806fce18ad38c4732d96008c506484940da7
a9b47cb7bc40f8bb70e079f8ae91e2b46d8d5d9bd1fa6ed637176d67a2a437ac801cca25f7e7c33b482d36f980da52982d65e6e388f2b2c47c7fcdfa797802
f2a5

  後臺接收次加密的串，先轉成字節，這裏又用到了一個靜態擴展HexDecode,轉成字節，採用RSACryptoServiceProvider對象導入私鑰進行解碼：

 public static byte[] HexDecode(this string me)
 {
     string s = me.Length % 2 == 1 ? "0" + me : me;
     byte[] data = new byte[s.Length / 2];
     for (int i = 0; i < data.Length; i++)
         {
            data[i] = byte.Parse(s.Substring(i + i, 2), NumberStyles.HexNumber);
         }
         return data;
  }
public static string GetString(this byte[] content, Encoding encoding = null)
{
     encoding = encoding ?? Encoding.ASCII;
     return encoding.GetString(content);
}

解密過程以下：

var pass = "9839c4f8cf40e5cd30be61a1e215c571424fca76108aacecc5ca45f9cdb6c207f4477eff32d41799babe915fd8806fce18ad38c4732d96008c50648494
0da7a9b47cb7bc40f8bb70e079f8ae91e2b46d8d5d9bd1fa6ed637176d67a2a437ac801cca25f7e7c33b482d36f980da52982d65e6e388f2b2c47c7fcdfa797802
f2a5";
byte[] data = pass.HexDecode();
RSACryptoServiceProvider rsa = new RSACryptoServiceProvider(1024);
rsa.ImportParameters(rsap);
var res = rsa.Decrypt(data, false);
Console.WriteLine(res.GetString());//用到上面靜態擴展，解密後結果爲zjt

RSA算法js實現