Chapter 3. Samba
Samba is an open-source implementation of the Server Message Block (SMB) and Common Internet File System (CIFS) protocols that provides file and print services between clients across various operating systems.[4]
In Red Hat Enterprise Linux, the samba package provides the Samba server. Run the
rpm -q samba
command to see if the samba package is installed. If it is not installed and you want to use Samba, run the following command as the root user to install it:
~]# yum install samba
3.1. Samba and SELinux
When SELinux is enabled, the Samba server (
smbd
) runs confined by default. Confined services run in their own domains, and are separated from other confined services. The following example demonstrates the smbd
process running in its own domain. This example assumes the samba package is installed:
- Run the
getenforce
command to confirm SELinux is running in enforcing mode:~]$
getenforce
EnforcingThegetenforce
command returnsEnforcing
when SELinux is running in enforcing mode. - Run the
service smbd start
command as the root user to startsmbd
:~]#
service smb start
Starting SMB services: [ OK ] - Run the
ps -eZ | grep smb
command to view thesmbd
processes:~]$
ps -eZ | grep smb
unconfined_u:system_r:smbd_t:s0 16420 ? 00:00:00 smbd unconfined_u:system_r:smbd_t:s0 16422 ? 00:00:00 smbdThe SELinux context associated with thesmbd
processes isunconfined_u:system_r:smbd_t:s0
. The second last part of the context,smbd_t
, is the type. A type defines a domain for processes and a type for files. In this case, thesmbd
processes are running in the smbd_t domain.
Files must be labeled correctly to allow
smbd
to access and share them. For example, smbd
can read and write to files labeled with the samba_share_t
type, but by default, cannot access files labeled with the httpd_sys_content_t
type, which is intended for use by the Apache HTTP Server. Booleans must be enabled to allow certain behavior, such as allowing home directories and NFS volumes to be exported through Samba, as well as to allow Samba to act as a domain controller.