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Full Discussion: Capture child processes and change return values question
Top Forums UNIX for Advanced & Expert Users Capture child processes and change return values question Post 302340917 by tuxhats on Tuesday 4th of August 2009 04:40:40 PM
Old 08-04-2009
Question Capture child processes and change return values question
Thanks in advance.
My environment is Ubuntu 9.04 desktop customized to be a high school classroom server for teaching code development. I have a unique "fake" jail called "lshell" which is very easy to setup and restricts users to commands that I dictate DISALLOWING ANYTHING ELSE. These questions below represent the last piece we would love to have for this open project.

I have a very specific need. I need to accomplish the following (without discussion about jail environments please).

I'd like users in a shell to enter "gedit" or other software/IDE, and do work. When the user makes a "File and Open" step they can only see or examine their directory and nowhere else.
Questions: Can I use one of the traces(l,p,s) or is their another way to restrict "what they can see"? Can these commands, along with some scripting, be used to return their top directory as $theirusername only and not be able to navigate elsewhere? Perhaps change some returning value say of
/home/jail/home/user to /user .

I can post the lshell.py script that I am using as the limited shell, if needed.

Thanks
 

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LEARN ABOUT DEBIAN

sss_useradd

SSS_USERADD(8)							 SSSD Manual pages						    SSS_USERADD(8)

NAME

       sss_useradd - create a new user

SYNOPSIS

       sss_useradd [options] LOGIN

DESCRIPTION

       sss_useradd creates a new user account using the values specified on the command line plus the default values from the system.

OPTIONS

       -u,--uid UID
	   Set the UID of the user to the value of UID. If not given, it is chosen automatically.

       -c,--gecos COMMENT
	   Any text string describing the user. Often used as the field for the user's full name.

       -h,--home HOME_DIR
	   The home directory of the user account. The default is to append the LOGIN name to /home and use that as the home directory. The base
	   that is prepended before LOGIN is tunable with "user_defaults/baseDirectory" setting in sssd.conf.

       -s,--shell SHELL
	   The user's login shell. The default is currently /bin/bash. The default can be changed with "user_defaults/defaultShell" setting in
	   sssd.conf.

       -G,--groups GROUPS
	   A list of existing groups this user is also a member of.

       -m,--create-home
	   Create the user's home directory if it does not exist. The files and directories contained in the skeleton directory (which can be
	   defined with the -k option or in the config file) will be copied to the home directory.

       -M,--no-create-home
	   Do not create the user's home directory. Overrides configuration settings.

       -k,--skel SKELDIR
	   The skeleton directory, which contains files and directories to be copied in the user's home directory, when the home directory is
	   created by sss_useradd.

	   This option is only valid if the -m (or --create-home) option is specified, or creation of home directories is set to TRUE in the
	   configuration.

       -Z,--selinux-user SELINUX_USER
	   The SELinux user for the user's login. If not specified, the system default will be used.

       -h,--help
	   Display help message and exit.

THE LOCAL DOMAIN

       In order to function correctly, a domain with "id_provider=local" must be created and the SSSD must be running.

       The administrator might want to use the SSSD local users instead of traditional UNIX users in cases where the group nesting (see
       sss_groupadd(8)) is needed. The local users are also useful for testing and development of the SSSD without having to deploy a full remote
       server. The sss_user* and sss_group* tools use a local LDB storage to store users and groups.

SEE ALSO

       sss_groupadd(8), sss_groupdel(8), sss_groupshow(8), sss_groupmod(8), sss_userdel(8), sss_usermod(8).

AUTHORS

       The SSSD upstream - http://fedorahosted.org/sssd

SSSD
								    03/04/2013							    SSS_USERADD(8)
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