% rwog(1) rwog 0.1.0 % Jesse Talavera-Greenberg % April 1, 2018

NAME

rwog - run without groups

SYNOPSIS

rwog -g \command-with-args...]

DESCRIPTION

rwog lets you run a given command while temporarily reducing your group membership. It does not modify /etc/group or /etc/passwd, and cannot grant you permissions you don't already have. Possible use cases for rwog include:

• In a shared system for which you are a privileged user, pretending that you are an unprivileged user without logging in as one.
• Testing a program's behavior when it doesn't have the group memberships it needs.

OPTIONS

-h, --help : Display the help.

-g, --groups : Run the given command without these groups, given by name (not number). You cannot drop your primary group membership (which is output by id -gn). Groups that don't exit or that you're not already a member of are ignored.

SEE ALSO

id(1), getent(1), groups(1), group(5)

BUGS

• Does not support gids given by number. When it does, such gids will be given of the form +gid_number, as is the case with most coreutils programs.

CAVEATS

rwog must have the capability CAP_SETGID in order to be used. Grant it with setcap $(which rwog) cap_setgid=pe if your package manager hasn't done so already. You could run it as root, but given that rwog is supposed to reduce privileges you'd be missing the point entirely.

I cannot promise that rwog is entirely secure. I'm not doing anything blatantly wrong, but it's possible that there's something I missed. Do not let untrusted users run rwog.

LICENSE

MIT.