crond_selinux(8) SELinux Policy documentation for crond crond_selinux(8)

NAME crond_selinux - Security Enhanced Linux Policy for the crond processes

DESCRIPTION Security-Enhanced Linux secures the crond processes via flexible manda- tory access control.

The crond processes execute with the crond_t SELinux type. You can check if you have these processes running by executing the ps command with the -Z qualifier.

For example:

ps -eZ | grep crond_t

ENTRYPOINTS The crond_t SELinux type can be entered via the "mtrr_device_t,unla- beled_t,proc_type,crond_exec_t,sysctl_type,filesystem_type,file_type" file types. The default entrypoint paths for the crond_t domain are the following:"

/dev/cpu/mtrr, /usr/sbin/cron(d)?, /usr/sbin/atd, /usr/sbin/fcron, all files on the system

PROCESS TYPES SELinux defines process types (domains) for each process running on the system

You can see the context of a process using the -Z option to ps

Policy governs the access confined processes have to files. SELinux crond policy is very flexible allowing users to setup their crond pro- cesses in as secure a method as possible.

The following process types are defined for crond:

crond_t, cronjob_t, crontab_t

Note: semanage permissive -a crond_t

can be used to make the process type crond_t permissive. Permissive process types are not denied access by SELinux. AVC messages will still be generated.

BOOLEANS SELinux policy is customizable based on least access required. crond policy is extremely flexible and has several booleans that allow you to manipulate the policy and run crond with the tightest access possible.

If you want to enable extra rules in the cron domain to support fcron, you must turn on the fcron_crond boolean.

setsebool -P fcron_crond 1

If you want to allow system cron jobs to relabel filesystem for restor- ing file contexts, you must turn on the cron_can_relabel boolean.

setsebool -P cron_can_relabel 1

If you want to enable extra rules in the cron domain to support fcron, you must turn on the fcron_crond boolean.

setsebool -P fcron_crond 1

If you want to allow system cron jobs to relabel filesystem for restor- ing file contexts, you must turn on the cron_can_relabel boolean.

setsebool -P cron_can_relabel 1

FILE CONTEXTS SELinux requires files to have an extended attribute to define the file type.

You can see the context of a file using the -Z option to ls

Policy governs the access confined processes have to these files. SELinux crond policy is very flexible allowing users to setup their crond processes in as secure a method as possible.

The following file types are defined for crond:

crond_exec_t

- Set files with the crond_exec_t type, if you want to transition an executable to the crond_t domain.

crond_initrc_exec_t

- Set files with the crond_initrc_exec_t type, if you want to transi- tion an executable to the crond_initrc_t domain.

crond_tmp_t

- Set files with the crond_tmp_t type, if you want to store crond tem- porary files in the /tmp directories.

crond_var_run_t

- Set files with the crond_var_run_t type, if you want to store the crond 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.

MANAGED FILES The SELinux process type crond_t can manage files labeled with the fol- lowing file types. The paths listed are the default paths for these file types. Note the processes UID still need to have DAC permissions.

file_type

all files on the system

COMMANDS semanage fcontext can also be used to manipulate default file context mappings.

semanage permissive can also be used to manipulate whether or not a process type is permissive.

semanage module can also be used to enable/disable/install/remove pol- icy modules.

semanage boolean can also be used to manipulate the booleans

system-config-selinux is a GUI tool available to customize SELinux pol- icy settings.

AUTHOR This manual page was auto-generated using sepolicy manpage by mgrepl.

SEE ALSO selinux(8), crond(8), semanage(8), restorecon(8), chcon(1), sepolicy(8) , setsebool(8), crontab_selinux(8)

crond 13-01-04 crond_selinux(8)