1crond_selinux(8)             SELinux Policy crond             crond_selinux(8)
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NAME

6       crond_selinux - Security Enhanced Linux Policy for the crond processes
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DESCRIPTION

9       Security-Enhanced Linux secures the crond processes via flexible manda‐
10       tory access control.
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12       The crond processes execute with the  crond_t  SELinux  type.  You  can
13       check  if  you have these processes running by executing the ps command
14       with the -Z qualifier.
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16       For example:
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18       ps -eZ | grep crond_t
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ENTRYPOINTS

23       The crond_t SELinux type can be entered via the crond_exec_t file type.
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25       The default entrypoint paths for the crond_t domain are the following:
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27       /usr/sbin/cron(d)?, /usr/sbin/atd, /usr/sbin/fcron, /usr/libexec/fcron
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PROCESS TYPES

30       SELinux defines process types (domains) for each process running on the
31       system
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33       You can see the context of a process using the -Z option to ps
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35       Policy  governs  the  access confined processes have to files.  SELinux
36       crond policy is very flexible allowing users to setup their crond  pro‐
37       cesses in as secure a method as possible.
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39       The following process types are defined for crond:
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41       crond_t
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43       Note:  semanage  permissive  -a crond_t can be used to make the process
44       type crond_t permissive. SELinux does not  deny  access  to  permissive
45       process  types, but the AVC (SELinux denials) messages are still gener‐
46       ated.
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BOOLEANS

50       SELinux policy is customizable based on least access  required.   crond
51       policy is extremely flexible and has several booleans that allow you to
52       manipulate the policy and run crond with the tightest access possible.
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56       If you want to determine whether crond can execute  jobs  in  the  user
57       domain  as  opposed to the the generic cronjob domain, you must turn on
58       the cron_userdomain_transition boolean. Enabled by default.
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60       setsebool -P cron_userdomain_transition 1
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63
64       If you want to allow users to resolve user passwd entries directly from
65       ldap  rather  then  using  a  sssd server, you must turn on the authlo‐
66       gin_nsswitch_use_ldap boolean. Disabled by default.
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68       setsebool -P authlogin_nsswitch_use_ldap 1
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72       If you want to deny user domains applications to map a memory region as
73       both  executable  and  writable,  this  is dangerous and the executable
74       should be reported in bugzilla, you must turn on the deny_execmem bool‐
75       ean. Enabled by default.
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77       setsebool -P deny_execmem 1
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80
81       If  you want to enable extra rules in the cron domain to support fcron,
82       you must turn on the fcron_crond boolean. Disabled by default.
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84       setsebool -P fcron_crond 1
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87
88       If you want to allow all domains to execute in fips_mode, you must turn
89       on the fips_mode boolean. Enabled by default.
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91       setsebool -P fips_mode 1
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95       If  you  want  to allow confined applications to run with kerberos, you
96       must turn on the kerberos_enabled boolean. Enabled by default.
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98       setsebool -P kerberos_enabled 1
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101
102       If you want to control the ability to mmap a low area  of  the  address
103       space,  as  configured  by /proc/sys/vm/mmap_min_addr, you must turn on
104       the mmap_low_allowed boolean. Disabled by default.
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106       setsebool -P mmap_low_allowed 1
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110       If you want to allow system to run with  NIS,  you  must  turn  on  the
111       nis_enabled boolean. Disabled by default.
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113       setsebool -P nis_enabled 1
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117       If  you  want to allow confined applications to use nscd shared memory,
118       you must turn on the nscd_use_shm boolean. Enabled by default.
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120       setsebool -P nscd_use_shm 1
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123
124       If you want to enable polyinstantiated directory support, you must turn
125       on the polyinstantiation_enabled boolean. Disabled by default.
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127       setsebool -P polyinstantiation_enabled 1
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130
131       If  you  want  to  disable  kernel module loading, you must turn on the
132       secure_mode_insmod boolean. Enabled by default.
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134       setsebool -P secure_mode_insmod 1
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137
138       If you want to allow unconfined executables to make their  heap  memory
139       executable.   Doing  this  is  a  really bad idea. Probably indicates a
140       badly coded executable, but could indicate an attack.  This  executable
141       should   be   reported  in  bugzilla,  you  must  turn  on  the  selin‐
142       uxuser_execheap boolean. Disabled by default.
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144       setsebool -P selinuxuser_execheap 1
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147
148       If you want to allow unconfined executables to make  their  stack  exe‐
149       cutable.   This  should  never, ever be necessary. Probably indicates a
150       badly coded executable, but could indicate an attack.  This  executable
151       should  be reported in bugzilla, you must turn on the selinuxuser_exec‐
152       stack boolean. Enabled by default.
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154       setsebool -P selinuxuser_execstack 1
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157
158       If you want to support NFS home  directories,  you  must  turn  on  the
159       use_nfs_home_dirs boolean. Disabled by default.
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161       setsebool -P use_nfs_home_dirs 1
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164
165       If  you  want  to  support SAMBA home directories, you must turn on the
166       use_samba_home_dirs boolean. Disabled by default.
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168       setsebool -P use_samba_home_dirs 1
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MANAGED FILES

173       The SELinux process type crond_t can manage files labeled with the fol‐
174       lowing  file  types.   The paths listed are the default paths for these
175       file types.  Note the processes UID still need to have DAC permissions.
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177       file_type
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179            all files on the system
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FILE CONTEXTS

183       SELinux requires files to have an extended attribute to define the file
184       type.
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186       You can see the context of a file using the -Z option to ls
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188       Policy  governs  the  access  confined  processes  have to these files.
189       SELinux crond policy is very flexible allowing  users  to  setup  their
190       crond processes in as secure a method as possible.
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192       STANDARD FILE CONTEXT
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194       SELinux  defines the file context types for the crond, if you wanted to
195       store files with these types in a diffent paths, you  need  to  execute
196       the  semanage  command  to  sepecify  alternate  labeling  and then use
197       restorecon to put the labels on disk.
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199       semanage fcontext -a -t crond_var_run_t '/srv/mycrond_content(/.*)?'
200       restorecon -R -v /srv/mycrond_content
201
202       Note: SELinux often uses regular expressions  to  specify  labels  that
203       match multiple files.
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205       The following file types are defined for crond:
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209       crond_exec_t
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211       -  Set  files  with the crond_exec_t type, if you want to transition an
212       executable to the crond_t domain.
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214
215       Paths:
216            /usr/sbin/cron(d)?,        /usr/sbin/atd,         /usr/sbin/fcron,
217            /usr/libexec/fcron
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220       crond_initrc_exec_t
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222       -  Set  files with the crond_initrc_exec_t type, if you want to transi‐
223       tion an executable to the crond_initrc_t domain.
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227       crond_tmp_t
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229       - Set files with the crond_tmp_t type, if you want to store crond  tem‐
230       porary files in the /tmp directories.
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234       crond_unit_file_t
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236       -  Set  files with the crond_unit_file_t type, if you want to treat the
237       files as crond unit content.
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240       Paths:
241            /usr/lib/systemd/system/atd.*, /usr/lib/systemd/system/crond.*
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244       crond_var_run_t
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246       - Set files with the crond_var_run_t type, if you  want  to  store  the
247       crond files under the /run or /var/run directory.
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250       Paths:
251            /var/run/.*cron.*,   /var/run/crond?.pid,  /var/run/crond?.reboot,
252            /var/run/atd.pid,     /var/run/fcron.pid,     /var/run/fcron.fifo,
253            /var/run/anacron.pid
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255
256       Note:  File context can be temporarily modified with the chcon command.
257       If you want to permanently change the file context you need to use  the
258       semanage fcontext command.  This will modify the SELinux labeling data‐
259       base.  You will need to use restorecon to apply the labels.
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COMMANDS

263       semanage fcontext can also be used to manipulate default  file  context
264       mappings.
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266       semanage  permissive  can  also  be used to manipulate whether or not a
267       process type is permissive.
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269       semanage module can also be used to enable/disable/install/remove  pol‐
270       icy modules.
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272       semanage boolean can also be used to manipulate the booleans
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274
275       system-config-selinux is a GUI tool available to customize SELinux pol‐
276       icy settings.
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AUTHOR

280       This manual page was auto-generated using sepolicy manpage .
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SEE ALSO

284       selinux(8),  crond(8),  semanage(8),  restorecon(8),  chcon(1),  sepol‐
285       icy(8), setsebool(8)
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289crond                              19-10-08                   crond_selinux(8)
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