updpwd_selinux (8) - Linux Manuals
updpwd_selinux: Security Enhanced Linux Policy for the updpwd processes
NAME
updpwd_selinux - Security Enhanced Linux Policy for the updpwd processesDESCRIPTION
Security-Enhanced Linux secures the updpwd processes via flexible mandatory access control.
The updpwd processes execute with the updpwd_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 updpwd_t
ENTRYPOINTS
The updpwd_t SELinux type can be entered via the updpwd_exec_t file type.
The default entrypoint paths for the updpwd_t domain are the following:
/sbin/unix_update, /usr/sbin/unix_update, /usr/sbin/pwhistory_helper
PROCESS TYPES
SELinux defines process types (domains) for each process running on the systemYou can see the context of a process using the -Z option to psP Policy governs the access confined processes have to files. SELinux updpwd policy is very flexible allowing users to setup their updpwd processes in as secure a method as possible.
The following process types are defined for updpwd:
updpwd_t
Note: semanage permissive -a updpwd_t can be used to make the process type updpwd_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated.
BOOLEANS
SELinux policy is customizable based on least access required. updpwd policy is extremely flexible and has several booleans that allow you to manipulate the policy and run updpwd with the tightest access possible.
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 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 use other domains file descriptors, you must turn on the domain_fd_use boolean. Enabled by default.
setsebool -P domain_fd_use 1
If you want to allow all domains to have the kernel load modules, you must turn on the domain_kernel_load_modules boolean. Disabled by default.
setsebool -P domain_kernel_load_modules 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 enable reading of urandom for all domains, you must turn on the global_ssp boolean. Disabled by default.
setsebool -P global_ssp 1
If you want to allow Apache to use mod_auth_pam, you must turn on the httpd_mod_auth_pam boolean. Disabled by default.
setsebool -P httpd_mod_auth_pam 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 nagios/nrpe to call sudo from NRPE utils scripts, you must turn on the nagios_run_sudo boolean. Disabled by default.
setsebool -P nagios_run_sudo 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. Disabled by default.
setsebool -P nscd_use_shm 1
MANAGED FILES
The SELinux process type updpwd_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.
etc_t
passwd_file_t
shadow_t
FILE CONTEXTS
SELinux requires files to have an extended attribute to define the file type.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 updpwd policy is very flexible allowing users to setup their updpwd processes in as secure a method as possible.
The following file types are defined for updpwd:
updpwd_exec_t
- Set files with the updpwd_exec_t type, if you want to transition an executable to the updpwd_t domain.
- Paths:
-
/sbin/unix_update, /usr/sbin/unix_update, /usr/sbin/pwhistory_helper
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.
COMMANDS
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.