Running worker processes under system resource restrictions.
This library provides an abstract interface for running various kinds of workers under resource restrictions. It was originally developed as part of the interactive-diagrams (http://github.com/co-dan/interactive-diagrams) project. To read more about the idia behind the library check out my GSoC report: http://parenz.wordpress.com/2013/07/15/interactive-diagrams-gsoc-progress-report/.
The library provides a convenient way of running worker processes, saving data obtained by the workers at start-up, a simple pool abstraction and a configurable security and resource limitations. Please consult https://github.com/co-dan/interactive-diagrams/tree/master/restricted-workers/README.md and https://github.com/co-dan/interactive-diagrams/wiki/Restricted-Workers for more details.
Warning: this library requires SELinux to function
Restricted Workers Library
This library provides an abstract interface for running various kinds of workers under resource restrictions. It was originally developed as part of the interactive-diagrams (project. You can read more about security restrictions in the wiki: <https://github.com/co-dan/interactive-diagrams/wiki/Restricted-Workers
The library provides a convenient way of running worker processes, saving data obtained by the workers at start-up, a simple pool abstraction and a configurable security and resource limitations.
Right now there are several kinds of security restrictions that could be applied to the worker process:
- RLimits
- chroot jail
- custom process euid
- cgroups
- process niceness
- SELinux security context
Documentation
The easiest way to get a grip of the restricted-workers library is to look at the examples below showing off the basic concepts of the library. Another good idea would be to read haddock documentations which feature comments for each exported function and type in the library. Do not hesitate to bug me if you think that the documentation in some places can be improved.
Examples
The following examples will walk you through creating basic kinds of workers (IOWorker), handling a pool of workers, communicating with workers using 'System.Restricted.Workers.Protocol' and creating your own types of workers.
- EchoWorker.lhs - basic usage of
IOWorker - EchoPool.lhs - basic usage of
Workers.Pool - CommandEvalProtocol.lhs - rewriting our Echo worker to use the provided Protocol module
- NewWorkerType.lhs - rolling out your own worker types
Wiki page
https://github.com/co-dan/interactive-diagrams/wiki/Restricted-Workers
External configurations
Some restrictions require external configuration, below we provide some example files for them that we use in interactive-diagrams:
SELinux configuration: https://github.com/co-dan/interactive-diagrams/tree/master/selinux
Run
build.shto build the policy module, thenload.shto load it. Read the blog post which explains the policy.CGroups: https://github.com/co-dan/interactive-diagrams/blob/master/cgconfig.conf
CGroups configuration is pretty straightforward. You can load the configuration with
cgconfigparser -l cgconfig.conf