python - 如何使用CSRF token进行跨域Ajax调用？

Question

我的 Django 应用程序模板中有一个典型的登录表单(直接使用 Bootstrap，而不是通过某些插件):

  <form class="form-signin" method="post" action="/site_manager/login/" id="form-signin"> {% csrf_token %}
       <h2 class="form-signin-heading">Please sign in</h2>
      <div class="control-group">
          <label class="control-label" for="login">Login:</label>
          <div class="controls">
              <input size="50" name="username" id="username" required="true" type="text" class="form-control" placeholder="Login" intermediateChanges=false>
          </div>
      </div>
      <div class="control-group">
          <label class="control-label" for="password">Password:</label>
          <div class="controls">
              <input size="50" name="password" id="password" required="true" type="password" class="form-control" placeholder="Password" intermediateChanges=false>
          </div>
      </div>
      <button name="submit" id="submit" value="Log in" type="submit" class="btn btn-primary pull-right">Sign in</button>
  </form>

这里是通过 requests module 进行远程认证的对应 View :

def login_view(request):
    if request.POST:
        username = request.POST.get('username')
        password = request.POST.get('password')
        headers = {'content-type': 'application/json', 'username':username, 'password':password}
        r = requests.get(remote_server_url, auth=(username, password), headers=headers)
        if r.status_code == 200:
            user = authenticate(username=username, password=password)
            if user == None:
                user = User.objects.create_user(username.encode('ascii', 'ignore'), "", password)
                user = authenticate(username=username, password=password)
            login(request, user)
            request.session.set_expiry(0)
            return HttpResponseRedirect('<index_page>')
        else:
            # redirects back to login page with some error message

登录成功后，我可以使用 Javascript 查询 CSRF token ，如所述 here ，我的计划是对远程服务器进行 Ajax 调用(通过 SSL)以用于其他目的(例如，RESTful 查询)。正如上面的代码所示，该服务器使用基本身份验证。所以我想在每个Ajax调用的 header 中设置CSRF token ，但这不遵循同源原则:

var csrftoken = $.cookie('csrftoken'); // using the jQuery Cookie plugin

$.ajaxSetup({
  headers: {
    'Authorization': "Basic XXXXX"
  }
  beforeSend: function(xhr, settings) {
    xhr.setRequestHeader("X-CSRFToken", csrftoken);
  }
});

$.ajax({
    type: "GET",
    dataType: "jsonp",
    url: remote_server_url+'/api/v1/someRESTfulResource/',
    contentType: 'application/json',
    success: function(data){
        // some operations with data
  }

});

Ajax调用和身份验证中使用的remote_server_url是相同的，并且它不与Django应用程序共享相同的域。据我所知，这是一个安全风险。出于同样的原因，我也不想在 Javascript 代码中提供纯文本密码。如何使用用户凭据安全地对远程服务器进行 Ajax 调用？

Answer 1

我在我想用 django 进行 Ajax POSTS 的页面的 Javascript 初始化中执行此操作:

$(document).ajaxSend(function(event, xhr, settings) {

  function sameOrigin(url) {                
    // url could be relative or scheme relative or absolute
    var host = document.location.host; // host + port
    var protocol = document.location.protocol;
    var sr_origin = '//' + host;
    var origin = protocol + sr_origin;              
    // Allow absolute or scheme relative URLs to same origin
    return (url == origin || url.slice(0, origin.length + 1) == origin + '/') ||
        (url == sr_origin || url.slice(0, sr_origin.length + 1) == sr_origin + '/') ||
        // or any other URL that isnt scheme relative or absolute i.e relative.
        !(/^(\/\/|http:|https:).*/.test(url));
  }
  function safeMethod(method) {
    return (/^(GET|HEAD|OPTIONS|TRACE)$/.test(method));
  }     
  if (!safeMethod(settings.type) && sameOrigin(settings.url)) {
      xhr.setRequestHeader("X-CSRFToken", '{{ csrf_token }}');
  }
});

我不记得在哪里找到它，但是使用它后我可以像这样执行 Ajax 帖子:

$.post("{% url 'foo' %}", "data="+myjson, function(data) {
  if(data['result']=="ok") {
    window.location.replace('{% url "bar" %}');
  } else {
    alert("Data Err!"); 
  }
}).error(function() { 
    alert("Ajax error!"); 
});