微信小程序登录数据解密及状态维持实例详解

本文实例讲述了微信小程序登录数据解密及状态维持。分享给大家供大家参考，具体如下：

学习过小程序的朋友应该知道，在小程序中是不支持cookie的，借助小程序中的缓存我们也可以存储一些信息，但是对于一些比较重要的信息，我们需要通过登录状态维持来保存，同时，为了安全起见，用户的敏感信息，也是需要加密在网络上传输的。

前台，service。封装了http请求，同时封装了getsession（通过code获取服务器生成的session）、getuserinfo（获取用户信息）、getdecryptiondata（解密数据）

//service.js
//封装了http服务,getuserinfo,提供回调函数
var recourse = {
 domain: "http://www.domain.com/"
}
module.exports = {
 //http get
 requestget: function (url, data, cb) {
  wx.request({
   url: recourse.domain + url,
   data: data,
   method: 'get',
   header: {},
   success: function (res) {
    cb(res, true)
   },
   fail: function () {
    cb(data, false)
   }
  })
 },
 //http post
 requestpost: function (url, data, cb) {
  wx.request({
   url: recourse.domain + url,
   data: data,
   method: 'post',
   header: {},
   success: function (res) {
    cb(res, true)
   },
   fail: function () {
    cb(data, false)
   }
  })
 },
 //获取第三方sessionid
 getsession: function (code, cb) {
  wx.request({
   url: recourse.domain + 'smallroutine/postcode',
   data: { code: code },
   method: 'post',
   success: function (res) {
    cb(res, true)
   },
   fail: function (res) {
    cb(res, false)
   }
  })
 },
 //获取用户信息
 getuserinfo: function (cb) {
  wx.getuserinfo({
   success: function (res) {
    cb(res, true)
   },
   fail: function (res) {
    cb(res, false)
   }
  })
 },
 //获取解密数据
 getdecryptiondata: function (cb) {
  wx.request({
   url: recourse.domain+'smallroutine/decryption',
   data: {
    encrypteddata: wx.getstoragesync('encrypteddata'),
    iv: wx.getstoragesync('iv'),
    session: wx.getstoragesync('thirdsessionid'),
   },
   method: 'post',
   success: function (res) {
    cb(res, true)
   },
   fail: function (res) {
    cb(res, false)
   }
  })
 }
}

后台，根据code获取session，客户端用来保持登录状态

[httppost]
public actionresult postcode(string code)
{
  try
  {
    if(!string.isnullorempty(code))
    {
      httpwebrequest request = (httpwebrequest)httpwebrequest.create(string.format("https://api.weixin.qq.com/sns/jscode2session?appid={0}&secret={1}&js_code={2}&grant_type=authorization_code",appid,appsecret,code));
      request.method = "get";
      httpwebresponse response = (httpwebresponse)request.getresponse();
      streamreader sr = new streamreader(response.getresponsestream());
      string content = sr.readtoend();
      if(response.statuscode == httpstatuscode.ok)
      {
        var successmodel = newtonsoft.json.jsonconvert.deserializeobject<validatecodesuccess>(content);
        if(null != successmodel.session_key)
        {
          //session_key是微信服务器生成的针对用户数据加密签名的密钥,不应该传输到客户端
          var session_key = successmodel.session_key;
          //3re_session用于服务器和小程序之间做登录状态校验
          var thirdsession = guid.newguid().tostring().replace("-","");
          var now = datetime.now;
          //存到数据库或者redis缓存,这里一小时过期
          service.addlogin(new domain.login()
          {
            code = code,
            createime = now,
            openid = successmodel.openid,
            overduetime = now.addminutes(60),
            sessionkey = successmodel.session_key,
            sessionrd = thirdsession
          });
          return json(new { success = true,session = thirdsession,openid = successmodel.openid });
        }
        else
        {
          var errmodel = newtonsoft.json.jsonconvert.deserializeobject<validatecodefail>(content);
          return json(new { success = false,msg = errmodel.errcode + ":" + errmodel.errmsg });
        }
      }
      else
      {
        var errmodel = newtonsoft.json.jsonconvert.deserializeobject<validatecodefail>(content);
        return json(new { success = false,msg = errmodel.errcode + ":" + errmodel.errmsg });
      }
    }
    else
    {
      return json(new { success = false,msg = "code不能为null" });
    }
  }
  catch(exception e)
  {
    return json(new { success = false });
  }
}

解密敏感信息

[httppost]
public actionresult decryption(string encrypteddata,string iv,string session)
{
  try
  {
    var sessionkey = service.getsessionkey(session);
    if(!string.isnullorempty(sessionkey))
    {
      var str = aesdecrypt(encrypteddata,sessionkey,iv);
      var data = newtonsoft.json.jsonconvert.deserializeobject<encrypteddata>(str);
      if(null != data)
      {
        //服务器可以更新用户信息
        return json(new { success = true,data = data });
      }
    }
  }
  catch(exception e)
  {
    service.addlog("翻译错误："+e.tostring());
  }
  return json(new { success = false });
}

aes解密

public static string aesdecrypt(string encrypteddata,string key,string iv)
{
  if(string.isnullorempty(encrypteddata)) return "";
  byte[] encrypteddata2 = convert.frombase64string(encrypteddata);
  system.security.cryptography.rijndaelmanaged rm = new system.security.cryptography.rijndaelmanaged
  {
    key = convert.frombase64string(key),
    iv = convert.frombase64string(iv),
    mode = system.security.cryptography.ciphermode.cbc,
    padding = system.security.cryptography.paddingmode.pkcs7
  };
  system.security.cryptography.icryptotransform ctf = rm.createdecryptor();
  byte[] resultarray = ctf.transformfinalblock(encrypteddata2,0,encrypteddata2.length);
  return encoding.utf8.getstring(resultarray);
}

判断用户是否掉线

[httppost]
public actionresult postsession(string session)
{
  if(!string.isnullorempty(session))
  {
    var logininfo = service.getlogininfo(session);
    if(null != logininfo)
    {
      return json(new { success = true,openid = logininfo.openid });
    }
    else
    {
      return json(new { success = false });
    }
  }
  return json(new { success = false });
}

前台index.js

//index.js
var app = getapp()
page({
 data: {
  userinfo: {},
 },
 onload: function () {
  var that = this
  app.getuserinfo(function (userinfo) {
   //更新数据
   that.setdata({
    userinfo: userinfo
   })
  })
 }
})

前台app.js

var service = require('./service/service.js')
var appconfig = {
  getuserinfo: function (cb) {
    var that = this
    if (that.globaldata.userinfo) {
      //从缓存中用户信息
    } else {
      //wx api 登录
      wx.login({
        success: function (res) {
          console.log('登录成功 code 为：' + res.code);
          if (res.code) {
            service.getsession(res.code, function (res, success) {
              if (success) {
                console.log('通过 code 获取第三方服务器 session 成功， session 为：' + res.data.session);
                //缓存起来
                wx.setstoragesync('thirdsessionid', res.data.session);
                //wx api 获取用户信息
                service.getuserinfo(function (res, success) {
                  if (success) {
                    console.log('获取用户信息成功， 加密数据为：' + res.encrypteddata);
                    console.log('获取用户信息成功， 加密向量为：' + res.iv);
                    //缓存敏感的用户信息,解密向量
                    wx.setstoragesync('encrypteddata', res.encrypteddata);
                    wx.setstoragesync('iv', res.iv);
                    that.globaldata.userinfo = res.userinfo;
                    //解密数据
                    service.getdecryptiondata(function (res, success) {
                      if (success) {
                        console.log("解密数据成功");
                        console.log(res.data.data);
                      } else {
                        console.log('解密数据失败');
                      }
                    })
                  } else {
                    console.log('获取用户信息失败')
                  }
                });
              } else {
                console.log('通过 code 获取第三方服务器 session 失败');
              }
            });
          } else {
            console.log('登录失败:');
          }
        }
      })
    }
  },
  globaldata: {
    userinfo: null
  }
}
app(appconfig)

运行输出

希望本文所述对大家微信小程序开发有所帮助。