Security-Enhanced Linux secures the ntpd processes via flexible mandatory access control.
If you want to allow users to resolve user passwd entries directly from ldap rather then using a sssd serve for the ntpd_t, you must turn on the authlogin_nsswitch_use_ldap boolean.
setsebool -P authlogin_nsswitch_use_ldap 1
If you want to allow confined applications to run with kerberos for the ntpd_t, you must turn on the kerberos_enabled boolean.
setsebool -P kerberos_enabled 1
You can see the context of a file using the -Z option to lsP Policy governs the access confined processes have to these files. SELinux ntpd policy is very flexible allowing users to setup their ntpd processes in as secure a method as possible.
The following file types are defined for ntpd:
ntpd_exec_t
- Set files with the ntpd_exec_t type, if you want to transition an executable to the ntpd_t domain.
ntpd_initrc_exec_t
- Set files with the ntpd_initrc_exec_t type, if you want to transition an executable to the ntpd_initrc_t domain.
ntpd_key_t
- Set files with the ntpd_key_t type, if you want to treat the files as ntpd key data.
ntpd_log_t
- Set files with the ntpd_log_t type, if you want to treat the data as ntpd log data, usually stored under the /var/log directory.
ntpd_tmp_t
- Set files with the ntpd_tmp_t type, if you want to store ntpd temporary files in the /tmp directories.
ntpd_tmpfs_t
- Set files with the ntpd_tmpfs_t type, if you want to store ntpd files on a tmpfs file system.
ntpd_unit_file_t
- Set files with the ntpd_unit_file_t type, if you want to treat the files as ntpd unit content.
ntpd_var_run_t
- Set files with the ntpd_var_run_t type, if you want to store the ntpd files under the /run directory.
ntpdate_exec_t
- Set files with the ntpdate_exec_t type, if you want to transition an executable to the ntpdate_t domain.
Note: File context can be temporarily modified with the chcon command. If you want to permanently change the file context you need to use the semanage fcontext command. This will modify the SELinux labeling database. You will need to use restorecon to apply the labels.
You can see the types associated with a port by using the following command:
semanage port -l
Policy governs the access confined processes have to these ports. SELinux ntpd policy is very flexible allowing users to setup their ntpd processes in as secure a method as possible.
The following port types are defined for ntpd:
Default Defined Ports: udp 123
You can see the context of a process using the -Z option to psP Policy governs the access confined processes have to files. SELinux ntpd policy is very flexible allowing users to setup their ntpd processes in as secure a method as possible.
The following process types are defined for ntpd:
ntpd_t
Note: semanage permissive -a PROCESS_TYPE can be used to make a process type permissive. Permissive process types are not denied access by SELinux. AVC messages will still be generated.
The SELinux user type ntpd_t can manage files label