LinuxQuestions.org
Visit Jeremy's Blog.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Security
User Name
Password
Linux - Security This forum is for all security related questions.
Questions, tips, system compromises, firewalls, etc. are all included here.

Notices

Reply
 
LinkBack Search this Thread
Old 07-11-2007, 12:45 PM   #1
Jzarecta
Member
 
Registered: Dec 2005
Location: Villahermosa, Bucharest, Birminham, Brooklyn, Beverly
Distribution: Mandriva
Posts: 115

Rep: Reputation: 15
Explaining Extended Attributes


I want to know the difference between ACL and ATTR. Is ACL based on ATTR, also what is ATTR a general porpouse tools.

I would also need to know the main difference between chattr and setfattr / chacl and setfacl. The main main description sound the same.

If I want to define a chacl, do I need to put all the elements (user owner, group, mask).
 
Old 07-11-2007, 12:54 PM   #2
MensaWater
Guru
 
Registered: May 2005
Location: Atlanta Georgia USA
Distribution: Redhat (RHEL), CentOS, Fedora, Debian, FreeBSD, HP-UX, Solaris, SCO
Posts: 5,774
Blog Entries: 4

Rep: Reputation: 697Reputation: 697Reputation: 697Reputation: 697Reputation: 697Reputation: 697
attr has more to do with a how a file is treated regardless of who accesses it.

acl has more to do with WHO can access it and what access they have to the file. It is like permissions (see chmod) on steroids.

That is to say the first one focuses on attributes of the file irrespective of users and the second focuses on permissions for users. You can set attr and acl on the same file.
 
Old 07-11-2007, 01:01 PM   #3
Jzarecta
Member
 
Registered: Dec 2005
Location: Villahermosa, Bucharest, Birminham, Brooklyn, Beverly
Distribution: Mandriva
Posts: 115

Original Poster
Rep: Reputation: 15
Quote:
Originally Posted by jlightner
attr has more to do with a how a file is treated regardless of who accesses it.

acl has more to do with WHO can access it and what access they have to the file. It is like permissions (see chmod) on steroids.

That is to say the first one focuses on attributes of the file irrespective of users and the second focuses on permissions for users. You can set attr and acl on the same file.
Right but acl, seems to be have the same concept only applied to 'ownership'. More like ownership oriented pre-defined attributes. Yet I don't see any utilities that will use the arbitrary attribute except a custom written backend that will know this attributes.
 
Old 07-11-2007, 01:36 PM   #4
Crito
Senior Member
 
Registered: Nov 2003
Location: Knoxville, TN
Distribution: Kubuntu 9.04
Posts: 1,168

Rep: Reputation: 53
The names seem pretty self-explanatory IMHO. Extended attributes are an extension of normal attributes (read, write and execute) and have absolutely nothing to do with ACLs -- my favorite is immutable BTW... even root can't delete a file with that set.
 
Old 07-11-2007, 02:12 PM   #5
MensaWater
Guru
 
Registered: May 2005
Location: Atlanta Georgia USA
Distribution: Redhat (RHEL), CentOS, Fedora, Debian, FreeBSD, HP-UX, Solaris, SCO
Posts: 5,774
Blog Entries: 4

Rep: Reputation: 697Reputation: 697Reputation: 697Reputation: 697Reputation: 697Reputation: 697
The "attr" is set on the file so it doesn't matter what the utility thinks should be done therefore nothing has to be written in the application to deal with it - the filesystem itself deals with it. he file's attr determines it. There is no "permission" in "attr" as there is in "acl". In the latter your utility has to be aware of acls in order to properly interpret them. In the former your utility doesn't need to interpret anything because the filesystem will determine what to do based on the file's attr regardless of what the utility wants to do.
 
  


Reply

Tags
acl, attributes, extended, metadata, setfacl


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Explaining python classes tangle Programming 3 09-05-2006 08:44 AM
Explaining nsswitch.conf clinton Linux - Networking 2 03-17-2006 01:57 PM
Need help in explaining Bash code Linh Programming 4 07-09-2004 10:50 AM
help explaining proftpd.conf file freekain Linux - Newbie 5 06-14-2004 08:08 AM
Explaining LogWatch details. Newbie here. buddhahat Linux - Newbie 1 11-09-2003 08:24 PM


All times are GMT -5. The time now is 10:39 AM.

Main Menu
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
identi.ca: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration