ownership
Compaq ownership tag retriever
see also :
biosdecode - dmidecode - vpddecode
Synopsis
ownership
[OPTIONS]
add an example, a script, a trick and tips
examples
source
How to make a file editable by two different users in different groups?
Rather than modify permissions on the directory, it might be
easier to put the user john into the www group.
Users can be in multiple groups. Use either usermod, edit the
/etc/group file, or if you have a GUI on your linux
machine use the graphical user manager program (might be called
different names based upon distro and desktop environment). The
easiest method is probably to open a command prompt, and type in:
sudo usermod -G www -a john
It'll ask for your account password, and once you enter it, the
user john will be have group level access to the /home/www
directory.
This is assuming the group www already has read/write/execute
access to the /home/www directory If that group doesn't have that
level of access then use chgrp www /home/www and
chmod g+rwx /home/www to take care of that.
note: if you are currently logged in as 'john', you may need to
log out and back in for your permissions to update.
source
Restrict device ownership to root only. But why?
Device file ownership means exactly the same thing as ownership
of any file; the user owner is allowed access via the
user permission bits (e.g. -rwx------) and can
change the permissions of the file, the group owner via the group
permission bits (e.g. ----rwx---), and everyone else
via the "others" permission bits (e.g. -------rwx).
You restrict ownership to root so that if a non-root
process has been compromised the perpetrator can't access the
device file or change its permission bits, thereby reducing the
security risk present.
source
shell script - How to output the owner of a file
I would use that function:
lso() { ls -dl ${1:?usage: lso file} | awk '{print $3;exit}'; }
Edit:
-
I thought about stat but I try to avoid using
anything non standard when possible. I sticked with something
portable (i.e. POSIX) as your question is tagged linux
and unix, not just linux with which
stat is quite standard..
-
As this question triggered a discussion about valid
usernames, these are also defined by a Unix standard to be a
string composed exclusively of characters from this list:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
a b c d e f g h i j k l m n o p q r s t u v w x y z
0 1 2 3 4 5 6 7 8 9 . _ -
with the additional restriction for the hyphen not to be the
first character.
I assumed no space was allowed. Just like anything else which is
non-portable this can lead to unexpected results not only with my
small function but with many Unix/Linux CLI utilities.
source
When I create files the owner / group is always root
You can't resolve it; the system is behaving as expected. The
sudoers file controls the sudo command, it does not change the
way the kernel interprets file and directory permissions. In
order to get the effects of sudo, you must run sudo. What sudo
does is run commands as root, so naturally files created by a
sudo-run command are owned by root.
source
What privilege is required to preserve ownership of a file on copy, and how do you get it?
See the capabilities(7) manual page – you
need the CAP_CHOWN capability to change file
ownership via chown(). (Root has all capabilities
enabled automatically. The manual page explains how to obtain
capabilities in other cases.)
There is no separate method/capability to just preserve
ownership, as Linux file copies are made by simply
reading/writing data to the destination file, then doing the same
with metadata. (For comparison, Windows NT has
SeBackupPrivilege and
SeRestorePrivilege privileges and the
BackupRead()/BackupWrite() calls.)
source
Have sudo create files under your own user id?
You can use tee. What tee does is write stdin to a
file and echo it on stdout too. Using it with a pipe and sudo
effectively changes the active user for output redirection. Bear
in mind that the left side of the pipe must actually write to
stdout, not stderr.
sudo fdisk -l | sudo -u myuser tee <file>
source
changing the ownership of a file in linux
Yes, you can add o+r, meaning, others can read:
chmod o+r test
source
Why user becomes nobody?
User alias
A possible explanation is that you already had a user called
nobody with the UID (User ID) 532. The result is you have created
a "user alias".
You either can try to specify another UID for your user (or let
the system pick-up one). Or you can leave it like that. The only
security risk is that if a service or other user can access
nobody's data then it will be able to access your
data.
NFS User ID Mapping
For users to have the feeling they are accessing their own files,
the UID on the NFS server should match the UID on the NFS
clients. Although, you want to avoid that for root
at least.
By default, NFS exportfs will choose UID/GID of 65534 which
corresponds to your user nobody's UID. You need to
instruct the NFS server not to map all UID to 65534 or if this is
the wanted behaviour, you need to specify the mapped default UID.
For the first case, remove the all_squash and
replace it by root_squash, but bare in mind that any
non root user with a similar UID between the NFS server and any
clients will be a match, so they own the files"
For the second case, keep the all_squash but add
anonuid=532 (you can use also anongid
for the GID (or Group ID)).
Example:
/ pc001(rw,root_squash)
/home/joe pc002(rw,all_squash,anonuid=532,anongid=100)
Note: the changes should be done in the file
/etc/exports on the NFS server.
source
Always have to chown when adding new file? Centos 6
Most likely, what is actually needed for the files to be
accessible is that their group is set to apache. You
can easily set it by default for new created files by running :
find /path/to/root/directory/of/website -type d -print0 | xargs -0 chmod g+s
This will set the setgid flag on all sub-directories
too. With this flag set, any new file created in there will
inherit the group of its parent directory. (-print0
and -0 options are designed to handle correctly
spaces in filenames)
Make sure ownerships of files are correct before running it. If
unsure, you can fix it the same way :
find /path/to/root/directory/of/website -print0 | xargs -0 chown apache:apache
source
Avoid errors from tar failing to restore directory permissions
This tar option might be what you're looking for:
--no-overwrite-dir
preserve metadata of existing directories
I tested as follows:
$ mkdir a b a/diffowner
$ sudo mkdir b/diffowner
$ sudo chmod a+w b/diffowner
$ echo foo > a/diffowner/foo
$ tar -C a -cvf test.tar diffowner
diffowner/
diffowner/foo
$ tar -C b --no-overwrite-dir -xvf test.tar diffowner
diffowner/
diffowner/foo
$ echo $?
0
description
ownership
retrieves and prints the "ownership tag" that can
be set on Compaq computers. Contrary to all other programs
of the dmidecode package, ownership
doesn’t print any version information, nor labels, but
only the raw ownership tag. This should help its integration
in scripts.
options
-d,
--dev-mem FILE
Read memory from device
FILE (default: /dev/mem)
-h, --help
Display usage information and
exit
-V, --version
Display the version and
exit
files
/dev/mem
see also
biosdecode ,
dmidecode , mem, vpddecode
author
Jean
Delvare