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 getenforce to confirm SELinux is running in enforcing mode:
$ getenforce
Enforcing
The getenforce command returns Enforcing when SELinux is running in enforcing mode.
Run service smbd start as the root user to start smbd:
service smb start
Starting SMB services: [ OK ]
Run ps -eZ | grep smb to view the smbd 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 smbd
The SELinux context associated with the smbd processes is unconfined_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, the smbd 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, can not access files labeled with the httpd_sys_content_t type, which is intended for use by the Apache HTTP Server. Booleans must be turned on to allow certain behavior, such as allowing home directories and NFS file systems to be exported through Samba, as well as to allow Samba to act as a domain controller.
