Security-Enhanced Linux secures the dhcpd processes via flexible mandatory access control.
If you want to allow dhcpc client applications to execute iptables commands, you must turn on the dhcpc_exec_iptables boolean.
setsebool -P dhcpc_exec_iptables 1
If you want to allow DHCP daemon to use LDAP backends, you must turn on the dhcpd_use_ldap boolean.
setsebool -P dhcpd_use_ldap 1
If you want to allow users to resolve user passwd entries directly from ldap rather then using a sssd serve for the dhcpd_t, dhcpc_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 dhcpd_t, dhcpc_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 dhcpd policy is very flexible allowing users to setup their dhcpd processes in as secure a method as possible.
The following file types are defined for dhcpd:
dhcpd_exec_t
- Set files with the dhcpd_exec_t type, if you want to transition an executable to the dhcpd_t domain.
dhcpd_initrc_exec_t
- Set files with the dhcpd_initrc_exec_t type, if you want to transition an executable to the dhcpd_initrc_t domain.
dhcpd_state_t
- Set files with the dhcpd_state_t type, if you want to treat the files as dhcpd state data.
dhcpd_tmp_t
- Set files with the dhcpd_tmp_t type, if you want to store dhcpd temporary files in the /tmp directories.
dhcpd_unit_file_t
- Set files with the dhcpd_unit_file_t type, if you want to treat the files as dhcpd unit content.
dhcpd_var_run_t
- Set files with the dhcpd_var_run_t type, if you want to store the dhcpd files under the /run directory.
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 dhcpd policy is very flexible allowing users to setup their dhcpd processes in as secure a method as possible.
The following port types are defined for dhcpd:
Default Defined Ports: tcp 68,546 udp 68,546
Default Defined Ports: tcp 547,548,647,847,7911 udp 67,547,548,647,847
You can see the context of a process using the -Z option to psP Policy governs the access confined processes have to files. SELinux dhcpd policy is very flexible allowing users to setup their dhcpd processes in as secure a method as possible.
The following process types are defined for dhcpd:
dhcpc_t, dhcpd_t
Note: semanage permissive -a PROCESS_TYPE can be used to make a process type permissive. Per