切记ajax中要带上AntiForgeryToken防止CSRF攻击

经常看到在项目中ajax post数据到服务器不加防伪标记，造成csrf攻击

在asp.net mvc里加入防伪标记很简单在表单中加入html.antiforgerytoken()即可。

html.antiforgerytoken()会生成一对加密的字符串，分别存放在cookies 和 input 中。

我们在ajax post中也带上antiforgerytoken

@model webapplication1.controllers.person
@{
 viewbag.title = "index";
}
<h2>index</h2>
<form id="form1">
 <div class="form-horizontal">
  <h4>persen</h4>
  <hr />
  @html.validationsummary(true, "", new { @class = "text-danger" })
  <div class="form-group">
   @html.labelfor(model => model.name, htmlattributes: new { @class = "control-label col-md-2" })
   <div class="col-md-10">
    @html.editorfor(model => model.name, new { htmlattributes = new { @class = "form-control" } })
    @html.validationmessagefor(model => model.name, "", new { @class = "text-danger" })
   </div>
  </div>
  <div class="form-group">
   @html.labelfor(model => model.age, htmlattributes: new { @class = "control-label col-md-2" })
   <div class="col-md-10">
    @html.editorfor(model => model.age, new { htmlattributes = new { @class = "form-control" } })
    @html.validationmessagefor(model => model.age, "", new { @class = "text-danger" })
   </div>
  </div>
  <div class="form-group">
   <div class="col-md-offset-2 col-md-10">
    <input type="button" id="save" value="create" class="btn btn-default" />
   </div>
  </div>
 </div>
</form>
<script src="~/scripts/jquery-1.10.2.min.js"></script>
<script src="~/scripts/jquery.validate.min.js"></script>
<script src="~/scripts/jquery.validate.unobtrusive.min.js"></script>
<script type="text/javascript">
 $(function () {
  //var token = $('[name=__requestverificationtoken]');
  //获取防伪标记
  var token = $('@html.antiforgerytoken()').val();
  var headers = {};
  //防伪标记放入headers
  //也可以将防伪标记放入data
  headers["__requestverificationtoken"] = token;
  $("#save").click(function () {
   $.ajax({
    type: 'post',
    url: '/home/index',
    cache: false,
    headers: headers,
    data: { name: "yangwen", age: "1" },
    success: function (data) {
     alert(data)
    },
    error: function () {
     alert("error")
    }
   });
  })
 })
</script>

放在cookies里面的加密字符串

控制器中代码

using system;
using system.collections.generic;
using system.linq;
using system.net;
using system.web;
using system.web.helpers;
using system.web.mvc;
namespace webapplication1.controllers
 {
 public class homecontroller : controller
  {
  public actionresult index()
   {
   return view();
   }
  [httppost]
  [myvalidateantiforgerytoken]
  public actionresult index(person p)
   {
   return json(true, jsonrequestbehavior.allowget);
   }
  }
 public class person
  {
  public string name { get; set; }
  public int age { get; set; }
  }
 public class myvalidateantiforgerytoken : authorizeattribute
  {
  public override void onauthorization(authorizationcontext filtercontext)
   {
   var request = filtercontext.httpcontext.request;
   if (request.httpmethod == webrequestmethods.http.post)
    {  
    if (request.isajaxrequest())
     {
     var antiforgerycookie = request.cookies[antiforgeryconfig.cookiename];
     var cookievalue = antiforgerycookie != null
      ? antiforgerycookie.value
      : null;
     //从cookies 和 headers 中 验证防伪标记
     //这里可以加try-catch
     antiforgery.validate(cookievalue, request.headers["__requestverificationtoken"]);
     }
    else
     {
     new validateantiforgerytokenattribute()
      .onauthorization(filtercontext);
     }
    }
   }
  }
 }

这里注释掉ajax中防伪标记在请求

$("#save").click(function () {
 $.ajax({
  type: 'post',
  url: '/home/index',
  cache: false,
 //  headers: headers,
  data: { name: "yangwen", age: "1" },
  success: function (data) {
   alert(data)
  },
  error: function () {
   alert("error")
  }
 });
})

默认返回500的状态码。

这里修改ajax中的防伪标记

  $(function () {
 //var token = $('[name=__requestverificationtoken]');
 //获取防伪标记
 var token = $('@html.antiforgerytoken()').val();
 var headers = {};
 //防伪标记放入headers
 //也可以将防伪标记放入data
 headers["__requestverificationtoken"] = token+11111111111111111111111111111111111;
 $("#save").click(function () {
  $.ajax({
   type: 'post',
   url: '/home/index',
   cache: false,
    headers: headers,
   data: { name: "yangwen", age: "1" },
   success: function (data) {
    alert(data)
   },
   error: function () {
    alert("error")
   }
  });
 })
})

也是500的状态码。

以上内容就是本文的全部叙述，切记ajax中要带上antiforgerytoken防止csrf攻击，小伙伴们在使用过程发现有疑问，请给我留言，谢谢！