Security-Enhanced Linux secures the getty processes via flexible mandatory access control.
The getty processes execute with the getty_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 getty_t
The getty_t SELinux type can be entered via the getty_exec_t file type.
The default entrypoint paths for the getty_t domain are the following:
/sbin/.*getty, /usr/sbin/.*getty
You can see the context of a process using the -Z option to psP Policy governs the access confined processes have to files. SELinux getty policy is very flexible allowing users to setup their getty processes in as secure a method as possible.
The following process types are defined for getty:
getty_t
Note: semanage permissive -a getty_t can be used to make the process type getty_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 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 logging in and using the system from /dev/console, you must turn on the login_console_enabled boolean. Enabled by default.
setsebool -P login_console_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
The SELinux process type getty_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.
getty_lock_t
getty_log_t
/var/log/mgetty.*.log.*
/var/log/vgetty.*.log.*
getty_tmp_t
getty_var_run_t
/var/spool/fax(/.*)?
/var/spool/voice(/.*)?
/var/run/mgetty.pid.*
/var/run/agetty.reload.*
initrc_var_run_t
/var/run/utmp
/var/run/random-seed
/var/run/runlevel.dir
/var/run/setmixer_flag
lockdev_lock_t
/var/lock/lockdev(/.*)?
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 getty policy is very flexible allowing users to setup their getty processes in as secure a method as possible.
STANDARD FILE CONTEXT
SELinux defines the file context types for the getty, 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 getty_unit_file_t '/srv/mygetty_content(/.*)?'
restorecon -R -v /srv/mygetty_content
Note: SELinux often uses regular expressions to specify labels that match multiple files.
The following file types are defined for getty:
getty_etc_t
- Set files with the getty_etc_t type, if you want to store getty files in the /etc directories.
getty_exec_t
- Set files with the getty_exec_t type, if you want to transition an executable to the getty_t domain.
getty_lock_t
- Set files with the getty_lock_t type, if you want to treat the files as getty lock data, stored under the /var/lock directory
getty_log_t
- Set files with the getty_log_t type, if you want to treat the data as getty log data, usually stored under the /var/log directory.
getty_tmp_t
- Set files with the getty_tmp_t type, if you want to store getty temporary files in the /tmp directories.
getty_unit_file_t
- Set files with the getty_unit_file_t type, if you want to treat the files as getty unit content.
getty_var_run_t
- Set files with the getty_var_run_t type, if you want to store the getty 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.