Security-Enhanced Linux secures the init processes via flexible mandatory access control.
The init processes execute with the init_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 init_t
The init_t SELinux type can be entered via the shell_exec_t, init_exec_t file types.
The default entrypoint paths for the init_t domain are the following:
/bin/d?ash, /bin/ksh.*, /bin/zsh.*, /usr/bin/d?ash, /usr/bin/ksh.*, /usr/bin/zsh.*, /bin/esh, /bin/bash, /bin/fish, /bin/mksh, /bin/sash, /bin/tcsh, /bin/yash, /bin/bash2, /usr/bin/esh, /sbin/nologin, /usr/bin/bash, /usr/bin/fish, /usr/bin/mksh, /usr/bin/sash, /usr/bin/tcsh, /usr/bin/yash, /usr/bin/bash2, /usr/sbin/sesh, /usr/sbin/smrsh, /usr/bin/scponly, /usr/libexec/sesh, /usr/sbin/nologin, /usr/bin/git-shell, /usr/sbin/scponlyc, /usr/libexec/sudo/sesh, /usr/bin/cockpit-bridge, /usr/libexec/cockpit-agent, /usr/libexec/git-core/git-shell, /sbin/init(ng)?, /usr/sbin/init(ng)?, /usr/lib/systemd/[^/]*, /usr/lib/systemd/system-generators/[^/]*, /bin/systemd, /sbin/upstart, /usr/bin/systemd, /usr/sbin/upstart
You can see the context of a process using the -Z option to psP Policy governs the access confined processes have to files. SELinux init policy is very flexible allowing users to setup their init processes in as secure a method as possible.
The following process types are defined for init:
init_t, initrc_t
Note: semanage permissive -a init_t can be used to make the process type init_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated.
If you want to allow users to resolve user passwd entries directly from ldap rather then using a sssd server, you must turn on the authlogin_nsswitch_use_ldap boolean. Disabled by default.
setsebool -P authlogin_nsswitch_use_ldap 1
If you want to deny all system processes and Linux users to use bluetooth wireless technology, you must turn on the deny_bluetooth boolean. Disabled by default.
setsebool -P deny_bluetooth 1
If you want to allow all domains to execute in fips_mode, you must turn on the fips_mode boolean. Enabled by default.
setsebool -P fips_mode 1
If you want to allow confined applications to run with kerberos, you must turn on the kerberos_enabled boolean. Enabled by default.
setsebool -P kerberos_enabled 1
If you want to allow system to run with NIS, you must turn on the nis_enabled boolean. Disabled by default.
setsebool -P nis_enabled 1
If you want to allow confined applications to use nscd shared memory, you must turn on the nscd_use_shm boolean. Enabled by default.
setsebool -P nscd_use_shm 1
If you want to allow create vbox modules during startup new kernel, you must turn on the use_virtualbox boolean. Disabled by default.
setsebool -P use_virtualbox 1
The SELinux process type init_t can manage files labeled with the following file types. The paths listed are the default paths for these file types. Note the processes UID still need to have DAC permissions.
auditd_etc_t
/etc/audit(/.*)?
binfmt_misc_fs_t
boolean_type
bpf_t
/sys/fs/bpf
cgroup_t
/sys/fs/cgroup
consolekit_log_t
/var/log/ConsoleKit(/.*)?
data_home_t
/root/.local/share(/.*)?
/home/[^/]+/.local/share(/.*)?
device_t
/dev/.*
/lib/udev/devices(/.*)?
/usr/lib/udev/devices(/.*)?
/dev
/etc/udev/devices
/var/named/chroot/dev
/var/spool/postfix/dev
/var/named/chroot_sdb/dev
etc_aliases_t
/etc/mail/.*.db
/etc/mail/aliases.*
/etc/postfix/aliases.*
/etc/aliases
/etc/aliases.db
etc_runtime_t
/[^/]+
/etc/mtab.*
/etc/blkid(/.*)?
/etc/nologin.*
/etc/.fstab.hal..+
/halt
/fastboot
/poweroff
/.autofsck
/etc/cmtab
/forcefsck
/.suspended
/fsckoptions
/.autorelabel
/etc/.updated
/var/.updated
/etc/killpower
/etc/nohotplug
/etc/securetty
/etc/ioctl.save
/etc/fstab.REVOKE
/etc/network/ifstate
/etc/sysconfig/hwconf
/etc/ptal/ptal-printd-like
/etc/sysconfig/iptables.save
/etc/xorg.conf.d/00-system-setup-keyboard.conf
/etc/X11/xorg.conf.d/00-system-setup-keyboard.conf
faillog_t
/var/log/btmp.*
/var/log/faillog.*
/var/log/tallylog.*
/var/run/faillock(/.*)?
gnome_home_type
init_tmp_t
init_var_lib_t
/var/lib/systemd(/.*)?
/var/lib/private/systemd(/.*)?
init_var_run_t
/var/run/systemd(/.*)?
initrc_state_t
initrc_var_run_t
/var/run/utmp
/var/run/random-seed
/var/run/runlevel.dir
/var/run/setmixer_flag
ipsec_var_run_t
/var/racoon(/.*)?
/var/run/pluto(/.*)?
/var/run/charon.*
/var/run/racoon.pid
/var/run/charon.ctl
/var/run/charon.vici
iscsi_lock_t
/var/lock/iscsi(/.*)?
krb5_host_rcache_t
/var/cache/krb5rcache(/.*)?
/var/tmp/nfs_0
/var/tmp/DNS_25
/var/tmp/host_0
/var/tmp/imap_0
/var/tmp/HTTP_23
/var/tmp/HTTP_48
/var/tmp/ldap_55
/var/tmp/ldap_487
/var/tmp/ldapmap1_0
krb5_keytab_t
/etc/krb5.keytab
/etc/krb5kdc/kadm5.keytab
/var/kerberos/krb5kdc/kadm5.keytab
lastlog_t
/var/log/lastlog.*
ld_so_cache_t
/etc/ld.so.cache
/etc/ld.so.cache~
/etc/ld.so.preload
/etc/ld.so.preload~
locale_t
/etc/locale.conf
/etc/vconsole.conf
/usr/lib/locale(/.*)?
/usr/share/locale(/.*)?
/usr/share/zoneinfo(/.*)?
/usr/share/X11/locale(/.*)?
/etc/timezone
/etc/localtime
/etc/sysconfig/clock
/etc/avahi/etc/localtime
/var/empty/sshd/etc/localtime
/var/named/chroot/etc/localtime
/var/spool/postfix/etc/localtime
lockfile
machineid_t
/etc/machine-id
/var/run/systemd/machine-id
mdadm_var_run_t
/dev/md/.*
/var/run/mdadm(/.*)?
/dev/.mdadm.map
mnt_t
/mnt(/[^/]*)?
/mnt(/[^/]*)?
/rhev(/[^/]*)?
/rhev/[^/]*/.*
/media(/[^/]*)?
/media(/[^/]*)?
/media/.hal-.*
/var/run/media(/[^/]*)?
/afs
/net
/misc
/rhev
mount_var_run_t
/run/mount(/.*)?
/dev/.mount(/.*)?
/var/run/mount(/.*)?
/var/run/davfs2(/.*)?
/var/cache/davfs2(/.*)?
named_conf_t
/etc/rndc.*
/etc/unbound(/.*)?
/var/named/chroot(/.*)?
/etc/named.rfc1912.zones
/var/named/chroot/etc/named.rfc1912.zones
/etc/named.conf
/var/named/named.ca
/etc/named.root.hints
/var/named/chroot/etc/named.conf
/etc/named.caching-nameserver.conf
/var/named/chroot/var/named/named.ca
/var/named/chroot/etc/named.root.hints
/var/named/chroot/etc/named.caching-nameserver.conf
passwd_file_t
/etc/group[-+]?
/etc/passwd[-+]?
/etc/passwd.adjunct.*
/etc/ptmptmp
/etc/.pwd.lock
/etc/group.lock
/etc/passwd.OLD
/etc/passwd.lock
print_spool_t
/var/spool/lpd(/.*)?
/var/spool/cups(/.*)?
/var/spool/cups-pdf(/.*)?
random_seed_t
/var/lib/random-seed
/usr/var/lib/random-seed
security_t
/selinux
svirt_file_type
sysctl_type
sysfs_t
/sys(/.*)?
systemd_home_t
/root/.local/share/systemd(/.*)?
/home/[^/]+/.local/share/systemd(/.*)?
systemd_logind_var_run_t
/var/run/.*nologin.*
/var/run/systemd/seats(/.*)?
/var/run/systemd/users(/.*)?
/var/run/systemd/shutdown(/.*)?
systemd_passwd_var_run_t
/var/run/systemd/ask-password(/.*)?
/var/run/systemd/ask-password-block(/.*)?
systemd_unit_file_type
tmpfs_t
/dev/shm
/var/run/shm
/usr/lib/udev/devices/shm
udev_rules_t
/etc/udev/rules.d(/.*)?
var_lib_nfs_t
/var/lib/nfs(/.*)?
var_lib_t
/opt/(.*/)?var/lib(/.*)?
/var/lib(/.*)?
var_log_t
/var/log/.*
/nsr/logs(/.*)?
/var/webmin(/.*)?
/var/log/secure[^/]*
/opt/zimbra/log(/.*)?
/var/log/maillog[^/]*
/var/log/spooler[^/]*
/var/log/messages[^/]*
/usr/centreon/log(/.*)?
/var/spool/rsyslog(/.*)?
/var/axfrdns/log/main(/.*)?
/var/spool/bacula/log(/.*)?
/var/tinydns/log/main(/.*)?
/var/dnscache/log/main(/.*)?
/var/stockmaniac/templates_cache(/.*)?
/opt/Symantec/scspagent/IDS/system(/.*)?
/var/log
/var/log/dmesg
/var/log/syslog
/var/named/chroot/var/log
var_run_t
/run/.*
/var/run/.*
/run
/var/run
/var/run
/var/spool/postfix/pid
wtmp_t
/var/log/wtmp.*
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 init policy is very flexible allowing users to setup their init processes in as secure a method as possible.
EQUIVALENCE DIRECTORIES
init policy stores data with multiple different file context types under the /var/run/systemd directory. If you would like to store the data in a different directory you can use the semanage command to create an equivalence mapping. If you wanted to store this data under the /srv dirctory you would execute the following command:
semanage fcontext -a -e /var/run/systemd /srv/systemd
restorecon -R -v /srv/systemd
STANDARD FILE CONTEXT
SELinux defines the file context types for the init, if you wanted to store files with these types in a diffent paths, you need to execute the semanage command to sepecify alternate labeling and then use restorecon to put the labels on disk.
semanage fcontext -a -t initrc_var_run_t '/srv/myinit_content(/.*)?'
restorecon -R -v /srv/myinit_content
Note: SELinux often uses regular expressions to specify labels that match multiple files.
The following file types are defined for init:
init_exec_t
- Set files with the init_exec_t type, if you want to transition an executable to the init_t domain.
init_tmp_t
- Set files with the init_tmp_t type, if you want to store init temporary files in the /tmp directories.
init_var_lib_t
- Set files with the init_var_lib_t type, if you want to store the init files under the /var/lib directory.
init_var_run_t
- Set files with the init_var_run_t type, if you want to store the init files under the /run or /var/run directory.
initctl_t
- Set files with the initctl_t type, if you want to treat the files as initctl data.
initrc_devpts_t
- Set files with the initrc_devpts_t type, if you want to treat the files as initrc devpts data.
initrc_exec_t
- Set files with the initrc_exec_t type, if you want to transition an executable to the initrc_t domain.
initrc_state_t
- Set files with the initrc_state_t type, if you want to treat the files as initrc state data.
initrc_tmp_t
- Set files with the initrc_tmp_t type, if you want to store initrc temporary files in the /tmp directories.
initrc_var_log_t
- Set files with the initrc_var_log_t type, if you want to treat the data as initrc var log data, usually stored under the /var/log directory.
initrc_var_run_t
- Set files with the initrc_var_run_t type, if you want to store the initrc files under the /run or /var/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.
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 policy modules.
semanage boolean can also be used to manipulate the booleans
system-config-selinux is a GUI tool available to customize SELinux policy settings.