Content-type: text/html Manpage of sysadm_selinux

sysadm_selinux

Section: sysadm SELinux Policy documentation (8)
Updated: sysadm
Index Return to Main Contents
 

NAME

sysadm_u - General system administration role - Security Enhanced Linux Policy

 

DESCRIPTION

sysadm_u is an SELinux User defined in the SELinux policy. SELinux users have default roles, sysadm_r. The default role has a default type, sysadm_t, associated with it.

The SELinux user will usually login to a system with a context that looks like:

sysadm_u:sysadm_r:sysadm_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 sysadm_u user, you would execute:

semanage login -m -s sysadm_u __default__

If you want to map the one Linux user (joe) to the SELinux user sysadm, you would execute:

$ semanage login -a -s sysadm_u joe

 

USER DESCRIPTION

The SELinux user sysadm_u is an admin user. It means that a mapped Linux user to this SELinux user is intended for administrative actions. Usually this is assigned to a root Linux user.

 

SUDO

The SELinux user sysadm can execute sudo.

You can set up sudo to allow sysadm to transition to an administrative domain:

Add one or more of the following record to sudoers using visudo.

USERNAME ALL=(ALL) ROLE=auditadm_r TYPE=auditadm_t COMMAND
sudo will run COMMAND as sysadm_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 sysadm_r to this list.

$ semanage user -m -R 'sysadm_r auditadm_r secadm_r staff_r user_r' sysadm_u

For more details you can see semanage man page.

USERNAME ALL=(ALL) ROLE=secadm_r TYPE=secadm_t COMMAND
sudo will run COMMAND as sysadm_u:secadm_r:secadm_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 sysadm_r to this list.

$ semanage user -m -R 'sysadm_r auditadm_r secadm_r staff_r user_r' sysadm_u

For more details you can see semanage man page.

USERNAME ALL=(ALL) ROLE=staff_r TYPE=staff_t COMMAND
sudo will run COMMAND as sysadm_u:staff_r:staff_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 sysadm_r to this list.

$ semanage user -m -R 'sysadm_r auditadm_r secadm_r staff_r user_r' sysadm_u

For more details you can see semanage man page.

USERNAME ALL=(ALL) ROLE=user_r TYPE=user_t COMMAND
sudo will run COMMAND as sysadm_u:user_r:user_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 sysadm_r to this list.

$ semanage user -m -R 'sysadm_r auditadm_r secadm_r staff_r user_r' sysadm_u

For more details you can see semanage man page.

The SELinux type sysadm_t is not allowed to execute sudo.

 

X WINDOWS LOGIN

The SELinux user sysadm_u is able to X Windows login.

 

NETWORK

The SELinux user sysadm_u is able to listen on the following tcp ports.

all ports with out defined types

ephemeral_port_t: 32768-61000

The SELinux user sysadm_u is able to connect to the following tcp ports.

all ports

The SELinux user sysadm_u is able to listen on the following udp ports.

all ports with out defined types

ntp_port_t: 123

ephemeral_port_t: 32768-61000

The SELinux user sysadm_u is able to connect to the following tcp ports.

all ports

 

BOOLEANS

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

If you want to allow the graphical login program to login directly as sysadm_r:sysadm_t, you must turn on the xdm_sysadm_login boolean.

setsebool -P xdm_sysadm_login 1

If you want to allow ssh logins as sysadm_r:sysadm_t, you must turn on the ssh_sysadm_login boolean.

setsebool -P ssh_sysadm_login 1

 

HOME_EXEC

The SELinux user sysadm_u is able execute home content files.

 

TRANSITIONS

Three things can happen when sysadm_t attempts to execute a program.

1. SELinux Policy can deny sysadm_t from executing the program.

2. SELinux Policy can allow sysadm_t to execute the program in the current user type.

Execute the following to see the types that the SELinux user sysadm_t can execute without transitioning:

sesearch -A -s sysadm_t -c file -p execute_no_trans

3. SELinux can allow sysadm_t to execute the program and transition to a new type.

Execute the following to see the types that the SELinux user sysadm_t can execute and transition:

$ sesearch -A -s sysadm_t -c process -p transition

 

MANAGED FILES

The SELinux user type sysadm_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(/.*)?


auditd_log_t

        /var/log/audit(/.*)?

       /var/log/audit.log


boolean_type


etc_runtime_t

        /[^/]+

       /etc/mtab.*

       /etc/blkid(/.*)?

       /etc/nologin.*

       /etc/.fstab.hal..+

       /halt

       /fastboot

       /poweroff

       /etc/cmtab

       /forcefsck

       /.autofsck

       /.suspended

       /fsckoptions

       /.autorelabel

       /etc/securetty

       /etc/nohotplug

       /etc/killpower

       /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


iceauth_home_t

        /root/.DCOP.*

       /root/.ICEauthority.*

       /home/[^/]*/.DCOP.*

       /home/[^/]*/.ICEauthority.*


krb5_host_rcache_t

        /var/cache/krb5rcache(/.*)?

       /var/tmp/nfs_0

       /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


non_security_file_type


screen_home_t

        /root/.screen(/.*)?

       /home/[^/]*/.screen(/.*)?

       /home/[^/]*/.screenrc


sysctl_type


systemd_passwd_var_run_t

        /var/run/systemd/ask-password(/.*)?

       /var/run/systemd/ask-password-block(/.*)?


systemd_unit_file_type


usbfs_t


user_fonts_cache_t

        /root/.fontconfig(/.*)?

       /root/.fonts/auto(/.*)?

       /root/.fonts.cache-.*

       /home/[^/]*/.fontconfig(/.*)?

       /home/[^/]*/.fonts/auto(/.*)?

       /home/[^/]*/.fonts.cache-.*


user_fonts_t

        /root/.fonts(/.*)?

       /tmp/.font-unix(/.*)?

       /home/[^/]*/.fonts(/.*)?


user_home_t

        /home/[^/]*/.+


user_home_type

        all user home files


user_tmp_type

        all user tmp files


user_tmpfs_type

        all user content in tmpfs file systems


xauth_home_t

        /root/.xauth.*

       /root/.Xauth.*

       /root/.serverauth.*

       /root/.Xauthority.*

       /var/lib/pqsql/.xauth.*

       /var/lib/pqsql/.Xauthority.*

       /var/lib/nxserve

 

Index

NAME
DESCRIPTION
USER DESCRIPTION
SUDO
X WINDOWS LOGIN
NETWORK
BOOLEANS
HOME_EXEC
TRANSITIONS
MANAGED FILES
This document was created by man2html, using the manual pages.
Time: 19:35:30 GMT, September 30, 2012