secadm_u − Security administrator role - Security Enhanced Linux Policy
secadm_u is an SELinux User defined in the SELinux policy. SELinux users have default roles, secadm_r. The default role has a default type, secadm_t, associated with it.
The SELinux user will usually login to a system with a context that looks like:
secadm_u:secadm_r:secadm_t:s0 - s0:c0.c1023
Linux users are automatically assigned an SELinux users at login. Login programs use the SELinux User to assign initial context to the user’s shell.
SELinux policy uses the context to control the user’s access.
By default all users are assigned to the SELinux user via the __default__ flag
On Targeted policy systems the __default__ user is assigned to the unconfined_u SELinux user.
You can list all Linux User to SELinux user mapping using:
semanage login -l
If you wanted to change the default user mapping to use the secadm_u user, you would execute:
semanage login -m -s secadm_u __default__
If you want to map the one Linux user (joe) to the SELinux user secadm, you would execute:
$ semanage login -a -s secadm_u joe
The SELinux user secadm_u is defined in policy as a unprivileged user. SELinux prevents unprivileged users from doing administration tasks without transitioning to a different role.
The SELinux user secadm can execute sudo.
You can set up sudo to allow secadm to transition to an administrative domain:
Add one or more of the following record to sudoers using visudo.
USERNAME
ALL=(ALL) ROLE=sysadm_r TYPE=sysadm_t COMMAND
sudo will run COMMAND as
secadm_u:sysadm_r:sysadm_t:LEVEL
You might also need to add one or more of these new roles to your SELinux user record.
List the SELinux roles your SELinux user can reach by executing:
$ semanage user -l |grep selinux_name
Modify the roles list and add secadm_r to this list.
$ semanage user -m -R ’secadm_r sysadm_r auditadm_r’ secadm_u
For more details you can see semanage man page.
USERNAME
ALL=(ALL) ROLE=auditadm_r TYPE=auditadm_t COMMAND
sudo will run COMMAND as
secadm_u:auditadm_r:auditadm_t:LEVEL
You might also need to add one or more of these new roles to your SELinux user record.
List the SELinux roles your SELinux user can reach by executing:
$ semanage user -l |grep selinux_name
Modify the roles list and add secadm_r to this list.
$ semanage user -m -R ’secadm_r sysadm_r auditadm_r’ secadm_u
For more details you can see semanage man page.
The SELinux type secadm_t is not allowed to execute sudo.
The SELinux user secadm_u is able to X Windows login.
The SELinux user secadm_u is able to listen on the following tcp ports.
6000-6020
1716
all ports without defined types
32768-60999
3689
all ports >= 1024
The SELinux user secadm_u is
able to connect to the following tcp
ports.
53,853
8955
all ports
389,636,3268,3269,7389
all ports without defined types
32768-60999
all ports < 1024
9080
88,750,4444
The SELinux user secadm_u is able to listen on the following udp ports.
all ports without defined types
32768-60999
all ports >= 1024
The SELinux user secadm_u is
able to connect to the following tcp
ports.
53,853
8955
all ports
389,636,3268,3269,7389
all ports without defined types
32768-60999
all ports < 1024
9080
88,750,4444
SELinux policy is customizable based on least access required. secadm policy is extremely flexible and has several booleans that allow you to manipulate the policy and run secadm with the tightest access possible.
If you want to determine whether crond can execute jobs in the user domain as opposed to the the generic cronjob domain, you must turn on the cron_userdomain_transition boolean. Enabled by default.
setsebool -P cron_userdomain_transition 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 deny user domains applications to map a memory region as both executable and writable, this is dangerous and the executable should be reported in bugzilla, you must turn on the deny_execmem boolean. Disabled by default.
setsebool -P deny_execmem 1
If you want to deny any process from ptracing or debugging any other processes, you must turn on the deny_ptrace boolean. Enabled by default.
setsebool -P deny_ptrace 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 determine whether calling user domains can execute Git daemon in the git_session_t domain, you must turn on the git_session_users boolean. Disabled by default.
setsebool -P git_session_users 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 pppd to be run for a regular user, you must turn on the pppd_for_user boolean. Disabled by default.
setsebool -P pppd_for_user 1
If you want to allow unconfined executables to make their stack executable. This should never, ever be necessary. Probably indicates a badly coded executable, but could indicate an attack. This executable should be reported in bugzilla, you must turn on the selinuxuser_execstack boolean. Enabled by default.
setsebool -P selinuxuser_execstack 1
If you want to allow users to connect to the local mysql server, you must turn on the selinuxuser_mysql_connect_enabled boolean. Disabled by default.
setsebool -P selinuxuser_mysql_connect_enabled 1
If you want to allow user to r/w files on filesystems that do not have extended attributes (FAT, CDROM, FLOPPY), you must turn on the selinuxuser_rw_noexattrfile boolean. Enabled by default.
setsebool -P selinuxuser_rw_noexattrfile 1
If you want to support NFS home directories, you must turn on the use_nfs_home_dirs boolean. Disabled by default.
setsebool -P use_nfs_home_dirs 1
If you want to support SAMBA home directories, you must turn on the use_samba_home_dirs boolean. Disabled by default.
setsebool -P use_samba_home_dirs 1
The SELinux user secadm_u is able execute home content files.
Three things can happen when secadm_t attempts to execute a program.
1.
SELinux Policy can deny secadm_t from executing the program.
2. SELinux Policy can allow secadm_t to execute the
program in the
current user type.
Execute the following to see the types that the SELinux user secadm_t can execute without transitioning:
sesearch -A -s secadm_t -c file -p execute_no_trans
3. SELinux can allow
secadm_t to execute the program and transition to
a new type.
Execute the following to see the types that the SELinux user secadm_t can execute and transition:
$ sesearch -A -s secadm_t -c process -p transition
The SELinux process type secadm_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.
alsa_home_t
/home/[ˆ/]+/.asoundrc |
auth_cache_t
/var/cache/coolkey(/.*)? |
boolean_type
chrome_sandbox_tmpfs_t
faillog_t
/var/log/btmp.* | |
/var/log/faillog.* | |
/var/log/tallylog.* | |
/var/run/faillock(/.*)? |
games_data_t
/var/games(/.*)? | |
/var/lib/games(/.*)? |
gconf_tmp_t
/tmp/gconfd-[ˆ/]+/.* |
gpg_agent_tmp_t
/home/[ˆ/]+/.gnupg/log-socket |
krb5_host_rcache_t
/var/tmp/krb5_0.rcache2 | |
/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 |
mail_spool_t
/var/mail(/.*)? | |
/var/spool/imap(/.*)? | |
/var/spool/mail(/.*)? | |
/var/spool/smtpd(/.*)? |
mqueue_spool_t
/var/spool/(client)?mqueue(/.*)? | |
/var/spool/mqueue.in(/.*)? |
pkcs_slotd_tmpfs_t
/dev/shm/var.lib.opencryptoki.* |
pulseaudio_tmpfs_t
pulseaudio_tmpfsfile
security_t
/selinux |
selinux_login_config_t
/etc/selinux/([ˆ/]*/)?logins(/.*)? |
semanage_store_t
/etc/selinux/([ˆ/]*/)?policy(/.*)? | |
/etc/selinux/(minimum|mls|targeted)/active(/.*)? | |
/etc/selinux/([ˆ/]*/)?modules/(active|tmp|previous)(/.*)? | |
/var/lib/selinux(/.*)? | |
/etc/share/selinux/mls(/.*)? | |
/etc/share/selinux/targeted(/.*)? |
session_dbusd_tmp_t
/var/run/user/[0-9]+/bus | |
/var/run/user/[0-9]+/dbus(/.*)? | |
/var/run/user/[0-9]+/dbus-1(/.*)? |
systemd_passwd_var_run_t
/var/run/systemd/ask-password(/.*)? | |
/var/run/systemd/ask-password-block(/.*)? |
usbfs_t
user_fonts_cache_t
/root/.fontconfig(/.*)? | |
/root/.fonts/auto(/.*)? | |
/root/.fonts.cache-.* | |
/root/.cache/fontconfig(/.*)? | |
/home/[ˆ/]+/.fontconfig(/.*)? | |
/home/[ˆ/]+/.fonts/auto(/.*)? | |
/home/[ˆ/]+/.fonts.cache-.* | |
/home/[ˆ/]+/.cache/fontconfig(/.*)? |
user_home_type
all user home files |
user_tmp_t
/dev/shm/mono.* | |
/var/run/user/[ˆ/]+ | |
/tmp/.ICE-unix(/.*)? | |
/tmp/.X11-unix(/.*)? | |
/dev/shm/pulse-shm.* | |
/tmp/.X0-lock | |
/var/run/user | |
/tmp/hsperfdata_root | |
/var/tmp/hsperfdata_root | |
/home/[ˆ/]+/tmp | |
/home/[ˆ/]+/.tmp | |
/var/run/user/[0-9]+ | |
/tmp/gconfd-[ˆ/]+ |
user_tmp_type
all user tmp files |
xserver_tmpfs_t
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 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.
This manual page was auto-generated using sepolicy manpage .
selinux(8), secadm(8), semanage(8), restorecon(8), chcon(1), sepolicy(8), setsebool(8), secadm_dbusd_selinux(8), secadm_dbusd_selinux(8), secadm_gkeyringd_selinux(8), secadm_gkeyringd_selinux(8), secadm_screen_selinux(8), secadm_screen_selinux(8), secadm_seunshare_selinux(8), secadm_seunshare_selinux(8), secadm_su_selinux(8), secadm_su_selinux(8), secadm_sudo_selinux(8), secadm_sudo_selinux(8), secadm_wine_selinux(8), secadm_wine_selinux(8)