How to give process specific privileges in windows

Question

Hi,

I am writing some testing software that receives some source code, compiles it on the server, executes it, forward input from the database, catches output and compares it with one in the database to see if it is correct. The problem is that source code can be anything (it is written in c/c++ and compiled with visual studio cl), so I need to prevent somehow malicious users. I am automatically killing those processes if they run longer than some time, or use more memory than allowed.

The question is, can I only allow those processes only to write and read from standard in/out streams and to deny any other access rights on windows.

Please excuse my English.

Thank you in advance.

Answer 1

Probably Job Objects can help you (see http://msdn.microsoft.com/en-us/library/ms684161(VS.85).aspx). This very powerful feature is not good known.

Working with jobs is very easy. You can create a job with respect of CreateJobObject and set a lot of different restrictions like time, memory and some restrictions. Then You can create a process with suspended flag, assign process to the job and resume the process. Then you receive full control under the created process and all tree of child processes, which the process can create. Job feature exist since Windows 2000.

Another modern way is User Interface Privilege Isolation (UIPI) (see http://msdn.microsoft.com/en-us/library/bb625963.aspx) or the way of usage Low Integrity Processes introduced by Vista. See http://msdn.microsoft.com/en-us/library/Bb250462#dse_stlip how to create a process with Low Integrity.