woj-land

This is a fork of woj-land on Google Code, of which the creator and maintainer is felix021.

Objectives

Enhancements to woj-land are planned.

Recently planned:

• Supports for interpreted languages (firstly, Python2, Python3 and Ruby)
• Supports for other languages requested (e.g. Scala, Clojure and Brainf**k)
• Distributed judging

Changes currently not in consideration:

• web (PHP IS THE BEST LANGUAGE IN THE WORLD!!!)

Thoughts on distributed judging

Replace judge-all.exe with a Python script which is in charge of distributing judge tasks to judge-all.exe processes on slave machines to minimize changes that have to be made.

Thoughts on supporting more languages

Pseudo-compiling the sources of interpreted languages, which means appending shebang at the start of the sources and chmoding the sources to make them executable, and then ./a.out. This should work for most interpreted languages.

For compiled languages, it's even simpler.

I should admit that there are no clear distinction between CLs and ILs (e.g. Java compiles and interpretes). Maybe I'll fuse the two classes in _fundamental.py in the future.

2014.12.28

I've just ACed "The A + B Problem" in Python and Ruby!!! If only I could gain access to the server and update with this extension.

However, I do notice that the RF Table method for restricting system calls may not be practical for Python and Ruby, of which the mechanism of running a simple program like "A + B" is basically overwhelming.

TODO find a method other than RF Table to restrict system calls. Maybe AST? MODIFY 2015/3/23 AST may be a lot of work and eventually lead to a dead end. Something related to runtime environment is mandatory here.

2015.3.23

After SO MUCH refactor, I finally managed to have my solution to the "A + B Problem" accepted in C/C++/Java/Pascal/Clojure/Python2/Python3 via the web interface.

And of course, I have left future maintainer with interfaces to adding new languages to WOJ. Instruction will be ready later.

TODO Add a tool that automatically determines the RF table for each language. And I'll try to export a patch and apply it to upstream server.

2015.3.27

A tool named syscall_recorder is ready. Check out syscall_recorder -h for more details. This tools utilizes strace.py from python-ptrace to record all the syscalls your target calls. An example call to syscall_recorder would be

./syscall_recorder python3 /home/user/woj/data/ . target1.py target2.py -n 1001
 1002 -l langs/ -f 5 -w read write close

After running this, syscall_recorder will record all the syscalls during the execution of target1.py running 1001 and target2.py running 1002. And a syscall table will be generated, in which each syscall will be assigned a number which shows how many times this syscall has been called. If this number exceeds a threshold of 5 (given by -f), it will be changed to -1, which means this syscall can be called infinite times without triggering the RF alarm. Syscalls on white list will automatically be given -1. syscall_recorder will generate a your_lang_rf.py according to the information it has gathered. And users can directly from your_lang_rf import rf to facilitate their security settings.

2015.4.7

With a lot of efforts, DJE finally came into being. Check out the sub-README.md to learn more. Remember, that starting small really helps.

Contact

For anything with regard to enhancements of woj-land, please file an issue.