1chronyd_selinux(8) SELinux Policy chronyd chronyd_selinux(8)
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6 chronyd_selinux - Security Enhanced Linux Policy for the chronyd pro‐
7 cesses
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10 Security-Enhanced Linux secures the chronyd processes via flexible
11 mandatory access control.
12 The chronyd processes execute with the chronyd_t SELinux type. You can
14 check if you have these processes running by executing the ps command
15 with the -Z qualifier.
16 For example:
18 ps -eZ | grep chronyd_t
20
24 The chronyd_t SELinux type can be entered via the chronyd_exec_t file
25 type.
26 The default entrypoint paths for the chronyd_t domain are the follow‐
28 ing:
29 /usr/sbin/chronyd, /usr/libexec/chrony-helper
31
33 SELinux defines process types (domains) for each process running on the
34 system
35 You can see the context of a process using the -Z option to ps
37 Policy governs the access confined processes have to files. SELinux
39 chronyd policy is very flexible allowing users to setup their chronyd
40 processes in as secure a method as possible.
41 The following process types are defined for chronyd:
43 chronyd_t
45 Note: semanage permissive -a chronyd_t can be used to make the process
47 type chronyd_t permissive. SELinux does not deny access to permissive
48 process types, but the AVC (SELinux denials) messages are still gener‐
49 ated.
50
53 SELinux policy is customizable based on least access required. chronyd
54 policy is extremely flexible and has several booleans that allow you to
55 manipulate the policy and run chronyd with the tightest access possi‐
56 ble.
57 If you want to allow users to resolve user passwd entries directly from
61 ldap rather then using a sssd server, you must turn on the authlo‐
62 gin_nsswitch_use_ldap boolean. Disabled by default.
63 setsebool -P authlogin_nsswitch_use_ldap 1
65 If you want to allow all daemons to write corefiles to /, you must turn
69 on the daemons_dump_core boolean. Disabled by default.
70 setsebool -P daemons_dump_core 1
72 If you want to enable cluster mode for daemons, you must turn on the
76 daemons_enable_cluster_mode boolean. Enabled by default.
77 setsebool -P daemons_enable_cluster_mode 1
79 If you want to allow all daemons to use tcp wrappers, you must turn on
83 the daemons_use_tcp_wrapper boolean. Disabled by default.
84 setsebool -P daemons_use_tcp_wrapper 1
86 If you want to allow all daemons the ability to read/write terminals,
90 you must turn on the daemons_use_tty boolean. Disabled by default.
91 setsebool -P daemons_use_tty 1
93 If you want to deny any process from ptracing or debugging any other
97 processes, you must turn on the deny_ptrace boolean. Enabled by
98 default.
99 setsebool -P deny_ptrace 1
101 If you want to allow any process to mmap any file on system with
105 attribute file_type, you must turn on the domain_can_mmap_files bool‐
106 ean. Enabled by default.
107 setsebool -P domain_can_mmap_files 1
109 If you want to allow all domains write to kmsg_device, while kernel is
113 executed with systemd.log_target=kmsg parameter, you must turn on the
114 domain_can_write_kmsg boolean. Disabled by default.
115 setsebool -P domain_can_write_kmsg 1
117 If you want to allow all domains to use other domains file descriptors,
121 you must turn on the domain_fd_use boolean. Enabled by default.
122 setsebool -P domain_fd_use 1
124 If you want to allow all domains to have the kernel load modules, you
128 must turn on the domain_kernel_load_modules boolean. Disabled by
129 default.
130 setsebool -P domain_kernel_load_modules 1
132 If you want to allow all domains to execute in fips_mode, you must turn
136 on the fips_mode boolean. Enabled by default.
137 setsebool -P fips_mode 1
139 If you want to enable reading of urandom for all domains, you must turn
143 on the global_ssp boolean. Disabled by default.
144 setsebool -P global_ssp 1
146 If you want to allow confined applications to run with kerberos, you
150 must turn on the kerberos_enabled boolean. Enabled by default.
151 setsebool -P kerberos_enabled 1
153 If you want to allow system to run with NIS, you must turn on the
157 nis_enabled boolean. Disabled by default.
158 setsebool -P nis_enabled 1
160 If you want to allow confined applications to use nscd shared memory,
164 you must turn on the nscd_use_shm boolean. Disabled by default.
165 setsebool -P nscd_use_shm 1
167
171 SELinux defines port types to represent TCP and UDP ports.
172 You can see the types associated with a port by using the following
174 command:
175 semanage port -l
177 Policy governs the access confined processes have to these ports.
180 SELinux chronyd policy is very flexible allowing users to setup their
181 chronyd processes in as secure a method as possible.
182 The following port types are defined for chronyd:
184 chronyd_port_t
187 Default Defined Ports:
191 udp 323
192
194 The SELinux process type chronyd_t can manage files labeled with the
195 following file types. The paths listed are the default paths for these
196 file types. Note the processes UID still need to have DAC permissions.
197 chronyd_tmpfs_t
199 chronyd_var_lib_t
202 /var/lib/chrony(/.*)?
204 chronyd_var_run_t
206 /var/run/chrony(/.*)?
208 /var/run/chronyd(/.*)?
209 /var/run/chrony-helper(/.*)?
210 /var/run/chronyd.pid
211 /var/run/chronyd.sock
212 cluster_conf_t
214 /etc/cluster(/.*)?
216 cluster_var_lib_t
218 /var/lib/pcsd(/.*)?
220 /var/lib/cluster(/.*)?
221 /var/lib/openais(/.*)?
222 /var/lib/pengine(/.*)?
223 /var/lib/corosync(/.*)?
224 /usr/lib/heartbeat(/.*)?
225 /var/lib/heartbeat(/.*)?
226 /var/lib/pacemaker(/.*)?
227 cluster_var_run_t
229 /var/run/crm(/.*)?
231 /var/run/cman_.*
232 /var/run/rsctmp(/.*)?
233 /var/run/aisexec.*
234 /var/run/heartbeat(/.*)?
235 /var/run/corosync-qnetd(/.*)?
236 /var/run/corosync-qdevice(/.*)?
237 /var/run/cpglockd.pid
238 /var/run/corosync.pid
239 /var/run/rgmanager.pid
240 /var/run/cluster/rgmanager.sk
241 gpsd_tmpfs_t
243 root_t
246 /sysroot/ostree/deploy/.*-atomic.*/deploy(/.*)?
248 /
249 /initrd
250 systemd_passwd_var_run_t
252 /var/run/systemd/ask-password(/.*)?
254 /var/run/systemd/ask-password-block(/.*)?
255 timemaster_tmpfs_t
257
261 SELinux requires files to have an extended attribute to define the file
262 type.
263 You can see the context of a file using the -Z option to ls
265 Policy governs the access confined processes have to these files.
267 SELinux chronyd policy is very flexible allowing users to setup their
268 chronyd processes in as secure a method as possible.
269 EQUIVALENCE DIRECTORIES
271 chronyd policy stores data with multiple different file context types
274 under the /var/run/chrony directory. If you would like to store the
275 data in a different directory you can use the semanage command to cre‐
276 ate an equivalence mapping. If you wanted to store this data under the
277 /srv dirctory you would execute the following command:
278 semanage fcontext -a -e /var/run/chrony /srv/chrony
280 restorecon -R -v /srv/chrony
281 STANDARD FILE CONTEXT
283 SELinux defines the file context types for the chronyd, if you wanted
285 to store files with these types in a diffent paths, you need to execute
286 the semanage command to sepecify alternate labeling and then use
287 restorecon to put the labels on disk.
288 semanage fcontext -a -t chronyd_var_run_t '/srv/mychronyd_con‐
290 tent(/.*)?'
291 restorecon -R -v /srv/mychronyd_content
292 Note: SELinux often uses regular expressions to specify labels that
294 match multiple files.
295 The following file types are defined for chronyd:
297 chronyd_exec_t
301 - Set files with the chronyd_exec_t type, if you want to transition an
303 executable to the chronyd_t domain.
304 Paths:
307 /usr/sbin/chronyd, /usr/libexec/chrony-helper
308 chronyd_initrc_exec_t
311 - Set files with the chronyd_initrc_exec_t type, if you want to transi‐
313 tion an executable to the chronyd_initrc_t domain.
314 chronyd_keys_t
318 - Set files with the chronyd_keys_t type, if you want to treat the
320 files as chronyd keys data.
321 chronyd_tmp_t
325 - Set files with the chronyd_tmp_t type, if you want to store chronyd
327 temporary files in the /tmp directories.
328 chronyd_tmpfs_t
332 - Set files with the chronyd_tmpfs_t type, if you want to store chronyd
334 files on a tmpfs file system.
335 chronyd_unit_file_t
339 - Set files with the chronyd_unit_file_t type, if you want to treat the
341 files as chronyd unit content.
342 chronyd_var_lib_t
346 - Set files with the chronyd_var_lib_t type, if you want to store the
348 chronyd files under the /var/lib directory.
349 chronyd_var_log_t
353 - Set files with the chronyd_var_log_t type, if you want to treat the
355 data as chronyd var log data, usually stored under the /var/log direc‐
356 tory.
357 chronyd_var_run_t
361 - Set files with the chronyd_var_run_t type, if you want to store the
363 chronyd files under the /run or /var/run directory.
364 Paths:
367 /var/run/chrony(/.*)?, /var/run/chronyd(/.*)?, /var/run/chrony-
368 helper(/.*)?, /var/run/chronyd.pid, /var/run/chronyd.sock
369 Note: File context can be temporarily modified with the chcon command.
372 If you want to permanently change the file context you need to use the
373 semanage fcontext command. This will modify the SELinux labeling data‐
374 base. You will need to use restorecon to apply the labels.
375
378 semanage fcontext can also be used to manipulate default file context
379 mappings.
380 semanage permissive can also be used to manipulate whether or not a
382 process type is permissive.
383 semanage module can also be used to enable/disable/install/remove pol‐
385 icy modules.
386 semanage port can also be used to manipulate the port definitions
388 semanage boolean can also be used to manipulate the booleans
390 system-config-selinux is a GUI tool available to customize SELinux pol‐
393 icy settings.
394
397 This manual page was auto-generated using sepolicy manpage .
398
401 selinux(8), chronyd(8), semanage(8), restorecon(8), chcon(1), sepol‐
402 icy(8) , setsebool(8)
403chronyd 19-04-25 chronyd_selinux(8)