Skip to main content

Securing JSESSIONID cookie if tomcat is fronted by apache

In my previous post Creating a custom Valve in tomcat I descibed the valve solution I tried to secure the JSESSIONID cookie but it didnt worked so finally I had to patch the tomcat class to get it working. We are using tomcat 5.5.28 so I downloaded the source and modify the class apache-tomcat-5.5.24-src/container/catalina/src/share/org/apache/catalina/connector/Response.java. In addCookie method I had to add this code


 String cookieName = cookie.getName();
 if (request != null && "JSESSIONID".equals(cookieName)) {
    String clientId = request.getHeader("X-Forwarded-For");
    if (clientId != null) {
  cookie.setSecure(true);
    }
 } 


Then compile the code and replace the catalina.jar in tomcathome/server/lib

Comments

  1. Cool! Did you send patch back to ASF guys? :)

    ReplyDelete
  2. no no its not a tomcat bug, but its the way we put apache/nginx in front of tomcat so that we don't want tomcat to handle SSL traffic. Apache handles SSL and by the time it reaches tomcat the request is no longer secure and thats why tomcat was not creating secure cookie. So it was a workaround to do it. This can also be used to set JSESSIONID a domain wide cookie in case you have diff tomcats using diff subdomain. I think newer tomcat may support this as an attribute already but we couldnt upgrade to new tomcat in this short timeframe.

    ReplyDelete

Post a Comment

Popular posts from this blog

Killing a particular Tomcat thread

Update: This JSP does not work on a thread that is inside some native code.  On many occasions I had a thread stuck in JNI code and it wont work. Also in some cases thread.stop can cause jvm to hang. According to javadocs " This method is inherently unsafe. Stopping a thread with Thread.stop causes it to unlock all of the monitors that it has locked". I have used it only in some rare occasions where I wanted to avoid a system shutdown and in some cases we ended up doing system shutdown as jvm was hung so I had a 70-80% success with it.   -------------------------------------------------------------------------------------------------------------------------- We had an interesting requirement. A tomcat thread that was spawned from an ExecutorService ThreadPool had gone Rogue and was causing lots of disk churning issues. We cant bring down the production server as that would involve downtime. Killing this thread was harmless but how to kill it, t

Adding Jitter to cache layer

Thundering herd is an issue common to webapp that rely on heavy caching where if lots of items expire at the same time due to a server restart or temporal event, then suddenly lots of calls will go to database at same time. This can even bring down the database in extreme cases. I wont go into much detail but the app need to do two things solve this issue. 1) Add consistent hashing to cache layer : This way when a memcache server is added/removed from the pool, entire cache is not invalidated.  We use memcahe from both python and Java layer and I still have to find a consistent caching solution that is portable across both languages. hash_ring and spymemcached both use different points for server so need to read/test more. 2) Add a jitter to cache or randomise the expiry time: We expire long term cache  records every 8 hours after that key was added and short term cache expiry is 2 hours. As our customers usually comes to work in morning and access the cloud file server it can happe

Preparing for an interview after being employed 11 years at a startup

I would say I didn't prepared a hell lot but  I did 2 hours in night every day and every weekend around 8 hours for 2-3 months. I did 20-30 leetcode medium problems from this list https://leetcode.com/explore/interview/card/top-interview-questions-medium/.  I watched the first 12 videos of Lecture Videos | Introduction to Algorithms | Electrical Engineering and Computer Science | MIT OpenCourseWare I did this course https://www.educative.io/courses/grokking-the-system-design-interview I researched on topics from https://www.educative.io/courses/java-multithreading-for-senior-engineering-interviews and leetcode had around 10 multithreading questions so I did those I watched some 10-20 videos from this channel https://www.youtube.com/channel/UCn1XnDWhsLS5URXTi5wtFTA