在登录时，前台页面的用户名、密码都是明文传输到后台的，漏洞扫描认为这样子不安全，就想到了前台js加密，后台解密的方法，要用到jsencrypt.js，具体代码如下：
前台页面：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head> ???<title></title> ???<script src="Scripts/jquery-1.4.1.min.js" type="text/javascript"></script> ???<script src="Scripts/jsencrypt.min.js" type="text/javascript"></script> ???<script type="text/javascript"> ???????function subData() { ???????????var encrypt = new JSEncrypt(); ???????????var publicKey = $("#pubkey").val(); ???????????encrypt.setPublicKey(publicKey); ???????????var userdata = {}; ???????????userdata.Username = encodeURI(encrypt.encrypt($("#tUsername").val())); ???????????userdata.Password = encodeURI(encrypt.encrypt($("#tPassword").val())); ???????????$.post("Handler1.ashx", userdata, function (r) { ???????????????alert(r); ???????????}); ???????} ???</script></head><body>用户名：<input type="text" id="tUsername" /><br />密码：<input type="password" id="tPassword" /><br /><input type="button" onclick="subData()" value="登录" /><textarea id="pubkey" rows="15" cols="65" style="display:none">MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDZpm0555ciZabX/1uVDI07cJUI66mcK2yf5FDB+KOKUrFyWY/xYS8csRDSN1vDfNnmdN45vGr+IMrEeZVqri/tvEL63N1JEWlKkvXolLpA6DHc/OKjXR9oQ93MDpftswOSdD5tQxplEDDemBeY2/Qh3RTBMGKsFuPoYKRxSQP7xwIDAQAB</textarea></body></html>后台处理程序：
using System;using System.Collections.Generic;using System.Web;using System.Security.Cryptography;using System.Text;using System.IO;namespace WebApplication1{ ???/// <summary> ???/// Handler1 的摘要说明 ???/// </summary> ???public class Handler1 : IHttpHandler ???{ ???????private const string privateKey = @"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"; ???????private const string publicKey = @"MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDZpm0555ciZabX/1uVDI07cJUI66mcK2yf5FDB+KOKUrFyWY/xYS8csRDSN1vDfNnmdN45vGr+IMrEeZVqri/tvEL63N1JEWlKkvXolLpA6DHc/OKjXR9oQ93MDpftswOSdD5tQxplEDDemBeY2/Qh3RTBMGKsFuPoYKRxSQP7xwIDAQAB"; ???????public void ProcessRequest(HttpContext context) ???????{ ???????????context.Response.ContentType = "text/plain"; ???????????string Username = context.Request["Username"]; ???????????string Password = context.Request["Password"]; ???????????//解密 ???????????RSACryptoService rsa = new RSACryptoService(privateKey, publicKey); ???????????Username = rsa.Decrypt(Username); ???????????Password = rsa.Decrypt(Password); ???????????context.Response.Write("ok"); ???????} ???????public bool IsReusable ???????{ ???????????get ???????????{ ???????????????return false; ???????????} ???????} ???} ???/// <summary> ???/// RSA类 ???/// </summary> ???public class RSACryptoService ???{ ???????private RSACryptoServiceProvider _privateKeyRsaProvider; ???????private RSACryptoServiceProvider _publicKeyRsaProvider; ???????public RSACryptoService(string privateKey, string publicKey = null) ???????{ ???????????if (!string.IsNullOrEmpty(privateKey)) ???????????{ ???????????????_privateKeyRsaProvider = CreateRsaProviderFromPrivateKey(privateKey); ???????????} ???????????if (!string.IsNullOrEmpty(publicKey)) ???????????{ ???????????????_publicKeyRsaProvider = CreateRsaProviderFromPublicKey(publicKey); ???????????} ???????} ???????public string Decrypt(string cipherText) ???????{ ???????????if (_privateKeyRsaProvider == null) ???????????{ ???????????????throw new Exception("_privateKeyRsaProvider is null"); ???????????} ???????????return Encoding.UTF8.GetString(_privateKeyRsaProvider.Decrypt(System.Convert.FromBase64String(cipherText), false)); ???????} ???????public string Encrypt(string text) ???????{ ???????????if (_publicKeyRsaProvider == null) ???????????{ ???????????????throw new Exception("_publicKeyRsaProvider is null"); ???????????} ???????????return Convert.ToBase64String(_publicKeyRsaProvider.Encrypt(Encoding.UTF8.GetBytes(text), false)); ???????} ???????private RSACryptoServiceProvider CreateRsaProviderFromPrivateKey(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; ???????} ???????private RSACryptoServiceProvider CreateRsaProviderFromPublicKey(string publicKeyString) ???????{ ???????????// encoded OID sequence for ?PKCS #1 rsaEncryption szOID_RSA_RSA = "1.2.840.113549.1.1.1" ???????????byte[] SeqOID = { 0x30, 0x0D, 0x06, 0x09, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x01, 0x05, 0x00 }; ???????????byte[] x509key; ???????????byte[] seq = new byte[15]; ???????????int x509size; ???????????x509key = Convert.FromBase64String(publicKeyString); ???????????x509size = x509key.Length; ???????????// --------- ?Set up stream to read the asn.1 encoded SubjectPublicKeyInfo blob ?------ ???????????using (MemoryStream mem = new MemoryStream(x509key)) ???????????{ ???????????????using (BinaryReader binr = new BinaryReader(mem)) ?//wrap Memory Stream with BinaryReader for easy reading ???????????????{ ???????????????????byte bt = 0; ???????????????????ushort twobytes = 0; ???????????????????twobytes = binr.ReadUInt16(); ???????????????????if (twobytes == 0x8130) //data read as little endian order (actual data order for Sequence is 30 81) ???????????????????????binr.ReadByte(); ???//advance 1 byte ???????????????????else if (twobytes == 0x8230) ???????????????????????binr.ReadInt16(); ??//advance 2 bytes ???????????????????else ???????????????????????return null; ???????????????????seq = binr.ReadBytes(15); ??????//read the Sequence OID ???????????????????if (!CompareBytearrays(seq, SeqOID)) ???//make sure Sequence for OID is correct ???????????????????????return null; ???????????????????twobytes = binr.ReadUInt16(); ???????????????????if (twobytes == 0x8103) //data read as little endian order (actual data order for Bit String is 03 81) ???????????????????????binr.ReadByte(); ???//advance 1 byte ???????????????????else if (twobytes == 0x8203) ???????????????????????binr.ReadInt16(); ??//advance 2 bytes ???????????????????else ???????????????????????return null; ???????????????????bt = binr.ReadByte(); ???????????????????if (bt != 0x00) ????//expect null byte next ???????????????????????return null; ???????????????????twobytes = binr.ReadUInt16(); ???????????????????if (twobytes == 0x8130) //data read as little endian order (actual data order for Sequence is 30 81) ???????????????????????binr.ReadByte(); ???//advance 1 byte ???????????????????else if (twobytes == 0x8230) ???????????????????????binr.ReadInt16(); ??//advance 2 bytes ???????????????????else ???????????????????????return null; ???????????????????twobytes = binr.ReadUInt16(); ???????????????????byte lowbyte = 0x00; ???????????????????byte highbyte = 0x00; ???????????????????if (twobytes == 0x8102) //data read as little endian order (actual data order for Integer is 02 81) ???????????????????????lowbyte = binr.ReadByte(); ?// read next bytes which is bytes in modulus ???????????????????else if (twobytes == 0x8202) ???????????????????{ ???????????????????????highbyte = binr.ReadByte(); //advance 2 bytes ???????????????????????lowbyte = binr.ReadByte(); ???????????????????} ???????????????????else ???????????????????????return null; ???????????????????byte[] modint = { lowbyte, highbyte, 0x00, 0x00 }; ??//reverse byte order since asn.1 key uses big endian order ???????????????????int modsize = BitConverter.ToInt32(modint, 0); ???????????????????int firstbyte = binr.PeekChar(); ???????????????????if (firstbyte == 0x00) ???????????????????{ ??//if first byte (highest order) of modulus is zero, don‘t include it ???????????????????????binr.ReadByte(); ???//skip this null byte ???????????????????????modsize -= 1; ??//reduce modulus buffer size by 1 ???????????????????} ???????????????????byte[] modulus = binr.ReadBytes(modsize); ??//read the modulus bytes ???????????????????if (binr.ReadByte() != 0x02) ???????????//expect an Integer for the exponent data ???????????????????????return null; ???????????????????int expbytes = (int)binr.ReadByte(); ???????// should only need one byte for actual exponent data (for all useful values) ???????????????????byte[] exponent = binr.ReadBytes(expbytes); ???????????????????// ------- create RSACryptoServiceProvider instance and initialize with public key ----- ???????????????????RSACryptoServiceProvider RSA = new RSACryptoServiceProvider(); ???????????????????RSAParameters RSAKeyInfo = new RSAParameters(); ???????????????????RSAKeyInfo.Modulus = modulus; ???????????????????RSAKeyInfo.Exponent = exponent; ???????????????????RSA.ImportParameters(RSAKeyInfo); ???????????????????return RSA; ???????????????} ???????????} ???????} ???????private bool CompareBytearrays(byte[] a, byte[] b) ???????{ ???????????if (a.Length != b.Length) ???????????????return false; ???????????int i = 0; ???????????foreach (byte c in a) ???????????{ ???????????????if (c != b[i]) ???????????????????return false; ???????????????i++; ???????????} ???????????return true; ???????} ???}}效果如下：
加密后的数据：
后台解密：
jsencrypt加密
原文地址：https://www.cnblogs.com/fanqf/p/10313545.html