File:  [NetBSD Developer Wiki] / wikisrc / projects / project / fs_scrub_flags.mdwn
Revision 1.2: download - view: text, annotated - select for diffs
Sun Nov 6 14:48:47 2011 UTC (4 years ago) by jmmv
Branches: MAIN
CVS tags: HEAD
Define the per-project category and difficulty at the template level,
instead of manually tagging the project pages.  While doing this, prefix
the tags with "category:" and "difficulty:" to make them easier to

[[!template id=project

title="Implement file system flags to scrub data blocks before deletion"


[Alistair G. Crooks](, [David Holland](

duration="3 months"

This project requires the implementation of a new mount option, and a new system and user file system flag, which, when set, will write random data over file system blocks before they are to be deleted. In the NetBSD kernel, this will take place at the time of the last unlink of a file, and when ftruncate is called.

The project will involve the investigation of retrieving or generating random data within the kernel, along with research into ways of retrieving large amounts of low-quality random data, such as LSFR, Mersenne twisters, and PRNGs. As well as implementing the file system flags within the kernel, user-level programs and library functions which manipulate the flags will need to be modified. Documentation detailing the new functionality must also be provided.


[[!tag gsoc]]

CVSweb for NetBSD wikisrc <> software: FreeBSD-CVSweb