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5.10.4. Archiving Files with tar

tar does not retain extended attributes by default. Since SELinux contexts are stored in extended attributes, contexts can be lost when archiving files. Use tar --selinux to create archives that retain contexts. If a Tar archive contains files without extended attributes, or if you want the extended attributes to match the system defaults, run the archive through /sbin/restorecon:
$ tar -xvf 
archive.tar
 | /sbin/restorecon -f -
Note: depending on the directory, you may need to be the Linux root user to run the /sbin/restorecon command.
The following example demonstrates creating a Tar archive that retains SELinux contexts:
  1. As the Linux root user, run the touch /var/www/html/file{1,2,3} command to create three files (file1, file2, and file3). These files inherit the httpd_sys_content_t type from the /var/www/html/ directory:
    # touch /var/www/html/file{1,2,3}
    # ls -Z /var/www/html/
    -rw-r--r--  root root unconfined_u:object_r:httpd_sys_content_t:s0 file1
    -rw-r--r--  root root unconfined_u:object_r:httpd_sys_content_t:s0 file2
    -rw-r--r--  root root unconfined_u:object_r:httpd_sys_content_t:s0 file3
    
  2. Run the cd /var/www/html/ command to change into the /var/www/html/ directory. Once in this directory, as the Linux root user, run the tar --selinux -cf test.tar file{1,2,3} command to create a Tar archive named test.tar.
  3. As the Linux root user, run the mkdir /test command to create a new directory, and then, run the chmod 777 /test/ command to allow all users full-access to the /test/ directory.
  4. Run the cp /var/www/html/test.tar /test/ command to copy the test.tar file in to the /test/ directory.
  5. Run the cd /test/ command to change into the /test/ directory. Once in this directory, run the tar -xvf test.tar command to extract the Tar archive.
  6. Run the ls -lZ /test/ command to view the SELinux contexts. The httpd_sys_content_t type has been retained, rather than being changed to default_t, which would have happened had the --selinux not been used:
    $ ls -lZ /test/
    -rw-r--r--  user1 group1 unconfined_u:object_r:httpd_sys_content_t:s0 file1
    -rw-r--r--  user1 group1 unconfined_u:object_r:httpd_sys_content_t:s0 file2
    -rw-r--r--  user1 group1 unconfined_u:object_r:httpd_sys_content_t:s0 file3
    -rw-r--r--  user1 group1 unconfined_u:object_r:default_t:s0 test.tar
    
  7. If the /test/ directory is no longer required, as the Linux root user, run the rm -ri /test/ command to remove it, as well as all files in it.
Refer to the tar(1) manual page for further information about tar, such as the --xattrs option that retains all extended attributes.

 
 
  Published under the terms of the GNU General Public License Design by Interspire