在 Tomcat 上禁止 HTTP 方法是否区分大小写？

Question

我已将以下内容放在我的应用程序的 web.xml 中以尝试禁止 PUT、DELETE 等：

 <security-constraint>
 <web-resource-collection>
  <web-resource-name>restricted methods</web-resource-name>
  <url-pattern>/*</url-pattern>
  <http-method>DELETE</http-method>
  <http-method>PUT</http-method>
  <http-method>SEARCH</http-method>
  <http-method>COPY</http-method>
  <http-method>MOVE</http-method>
  <http-method>PROPFIND</http-method>
  <http-method>PROPPATCH</http-method>
  <http-method>MKCOL</http-method>
  <http-method>LOCK</http-method>
  <http-method>UNLOCK</http-method>
  <http-method>delete</http-method>
  <http-method>put</http-method>
  <http-method>search</http-method>
  <http-method>copy</http-method>
  <http-method>move</http-method>
  <http-method>propfind</http-method>
  <http-method>proppatch</http-method>
  <http-method>mkcol</http-method>
  <http-method>lock</http-method>
  <http-method>unlock</http-method>
 </web-resource-collection>
 <auth-constraint />
 </security-constraint>

好的，现在：

如果我使用方法提出请求，DELETE我会得到 403 返回。

如果我使用方法提出请求，delete我会得到 403 返回。

但

如果我用DeLeTe我的方法做一个请求就OK了！

我怎样才能让它禁止这些不区分大小写的？

编辑：我正在用 C# 程序测试它：

    private void button1_Click(object sender, EventArgs e)
    {
        textBox1.Text = "making request";
        System.Threading.Thread.Sleep(400);
        WebRequest req = WebRequest.Create("http://serverurl/Application/cache_test.jsp");
        req.Method = txtMethod.Text;
        try
        {
            HttpWebResponse resp = (HttpWebResponse)req.GetResponse();

            textBox1.Text = "Status: " + resp.StatusCode;

            if (resp.StatusCode == System.Net.HttpStatusCode.OK)
            {
                WebHeaderCollection header = resp.Headers;
                using (System.IO.StreamReader reader = new System.IO.StreamReader(resp.GetResponseStream(), ASCIIEncoding.ASCII))
                {
                    //string responseText = reader.ReadToEnd();
                    textBox1.Text += "\r\n" + reader.ReadToEnd();
                }
            }
        }
        catch (Exception ex)
        {
            textBox1.Text = ex.Message;
        }
    }

txtMethod.Text是一个文本框，我在其中输入方法名称。当出现 403 时，会抛出异常，并在 catch 块中捕获该异常。

cache_test.jsp 包含：

<%
response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate, post-check=0, pre-check=0");
response.setHeader("Pragma","no-cache");

out.print("Method used was: "+request.getMethod());
%>

Answer 1

不管 Tomcat 在 HTTP 标准方面的错误行为如何，您都应该使用白名单来允许特定方法而不是黑名单。

例如，以下白名单将阻止除区分大小写 GET和HEAD.

<security-constraint>
    <web-resource-collection>
        <web-resource-name>restricted methods</web-resource-name>
        <url-pattern>/*</url-pattern>
        <http-method-omission>GET</http-method-omission>
        <http-method-omission>HEAD</http-method-omission>
    </web-resource-collection>
    <auth-constraint />
</security-constraint>

（注意：需要 Tomcat 7+。使用旧版本的用户必须研究其他解决方案，例如 servlet 过滤器。）

参考

Answer 2

好吧，在对一些Server: Apache-Coyotte在其 HTTP 回复中包含标头签名的随机服务器进行快速测试后，似乎您是正确的，因为get / HTTP/1.1\r\nHost: <target_IP>\r\n\r\n每次使用简单的 netcat 连接发送都可以工作，而应该收到 400 HTTP 代码。

例如 ：

$ { echo -en "get / HTTP/1.1\r\nHost: <target_IP>:8080\r\n\r\n" ; } | nc <target_IP> 8080

01:14:58.095547 IP 192.168.1.3.57245 > <target_IP>.8080: Flags [P.], seq 1:42, ack 1, win 115, options [nop,nop,TS val 4294788321 ecr 0], length 41
E..]C.@.@..Y......p.....A..v.......s.......
..D.....get / HTTP/1.1
Host: <target_IP>:8080

[...]

01:14:58.447946 IP <target_IP>.8080 > 192.168.1.3.57245: Flags [.], seq 1:1409, ack 43, win 65494, options [nop,nop,TS val 7981294 ecr 4294787971], length 1408
E...f...i.....p.............A..............
.y....C.HTTP/1.1 200 OK
Server: Apache-Coyote/1.1
Content-Type: text/html;charset=ISO-8859-1
Transfer-Encoding: chunked
Date: Tue, 27 Jan 2015 00:15:14 GMT

我必须说我在这里有点震惊，在这种情况下看到这种行为扩展到所有 HTTP/1.1 方法我不会感到惊讶。

您应该在他们的错误跟踪工具上填写错误报告并将邮件发送到适当的邮件列表，因为这是对 RFC 2616（见下文）的一个丑陋的违反，会产生不良后果。

5.1.1 方法

  The Method  token indicates the method to be performed on the
  resource identified by the Request-URI. The method is case-sensitive.

      Method         = "OPTIONS"                ; Section 9.2
                     | "GET"                    ; Section 9.3
                     | "HEAD"                   ; Section 9.4
                     | "POST"                   ; Section 9.5
                     | "PUT"                    ; Section 9.6
                     | "DELETE"                 ; Section 9.7
                     | "TRACE"                  ; Section 9.8
                     | "CONNECT"                ; Section 9.9
                     | extension-method
      extension-method = token