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5.9.4. Archiving Files with tar

The tar utility does not retain extended attributes by default. Since SELinux contexts are stored in extended attributes, contexts can be lost when archiving files. Use the tar --selinux command to create archives that retain contexts and to restore files from the archives. If a tar archive contains files without extended attributes, or if you want the extended attributes to match the system defaults, use the restorecon utility:
~]$ tar -xvf archive.tar | restorecon -f -
Note that depending on the directory, you may need to be the root user to run the restorecon.
The following example demonstrates creating a tar archive that retains SELinux contexts:

Procedure 5.10. Creating a tar Archive

  1. Change to the /var/www/html/ directory and view its SELinux context:
    ~]$ cd /var/www/html/
    html]$ ls -dZ /var/www/html/
    drwxr-xr-x. root root system_u:object_r:httpd_sys_content_t:s0 .
  2. As root, create three files (file1, file2, and file3) in /var/www/html/. These files inherit the httpd_sys_content_t type from /var/www/html/:
    html]# touch file{1,2,3}
    html]$ 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
  3. As root, run the following command to create a tar archive named test.tar. Use the --selinux to retain the SELinux context:
    html]# tar --selinux -cf test.tar file{1,2,3}
  4. As root, create a new directory named /test/, and then allow all users full access to it:
    ~]# mkdir /test
    ~]# chmod 777 /test/
  5. Copy the test.tar file into /test/:
    ~]$ cp /var/www/html/test.tar /test/
  6. Change into /test/ directory. Once in this directory, run the following command to extract the tar archive. Specify the --selinux option again otherwise the SELinux context will be changed to default_t:
    ~]$ cd /test/
    test]$ tar --selinux -xvf test.tar
  7. 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:
    test]$ 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
  8. If the /test/ directory is no longer required, as root, run the following command to remove it, as well as all files in it:
    ~]# rm -ri /test/
See the tar(1) manual page for further information about tar, such as the --xattrs option that retains all extended attributes.