passwd_selinux(8) SELinux Policy passwd passwd_selinux(8)NAMEpasswd_selinux - Security Enhanced Linux Policy for the passwd pro‐
cesses
DESCRIPTION
Security-Enhanced Linux secures the passwd processes via flexible
mandatory access control.
The passwd processes execute with the passwd_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 passwd_t
ENTRYPOINTS
The passwd_t SELinux type can be entered via the passwd_exec_t file
type.
The default entrypoint paths for the passwd_t domain are the following:
/usr/bin/chage, /usr/bin/passwd
PROCESS TYPES
SELinux defines process types (domains) for each process running on the
system
You can see the context of a process using the -Z option to ps
Policy governs the access confined processes have to files. SELinux
passwd policy is very flexible allowing users to setup their passwd
processes in as secure a method as possible.
The following process types are defined for passwd:
passwd_t
Note: semanage permissive -a passwd_t can be used to make the process
type passwd_t permissive. SELinux does not deny access to permissive
process types, but the AVC (SELinux denials) messages are still gener‐
ated.
BOOLEANS
SELinux policy is customizable based on least access required. passwd
policy is extremely flexible and has several booleans that allow you to
manipulate the policy and run passwd 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 authlo‐
gin_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 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 samba to act as the domain controller, add users,
groups and change passwords, you must turn on the samba_domain_con‐
troller boolean. Disabled by default.
setsebool -P samba_domain_controller 1
NSSWITCH DOMAIN
If you want to allow users to resolve user passwd entries directly from
ldap rather then using a sssd server for the passwd_t, you must turn on
the authlogin_nsswitch_use_ldap boolean.
setsebool -P authlogin_nsswitch_use_ldap 1
If you want to allow confined applications to run with kerberos for the
passwd_t, you must turn on the kerberos_enabled boolean.
setsebool -P kerberos_enabled 1
MANAGED FILES
The SELinux process type passwd_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.
faillog_t
/var/log/btmp.*
/var/log/faillog.*
/var/log/tallylog.*
/var/run/faillock(/.*)?
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
lastlog_t
/var/log/lastlog.*
passwd_file_t
/etc/group[-+]?
/etc/passwd[-+]?
/etc/passwd.adjunct.*
/etc/ptmptmp
/etc/.pwd.lock
/etc/group.lock
/etc/passwd.OLD
/etc/passwd.lock
security_t
/selinux
shadow_t
/etc/shadow.*
/etc/gshadow.*
/etc/nshadow.*
/var/db/shadow.*
/etc/security/opasswd
/etc/security/opasswd.old
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 ls
Policy governs the access confined processes have to these files.
SELinux passwd policy is very flexible allowing users to setup their
passwd processes in as secure a method as possible.
STANDARD FILE CONTEXT
SELinux defines the file context types for the passwd, 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 passwd_exec_t '/srv/passwd/content(/.*)?'
restorecon -R -v /srv/mypasswd_content
Note: SELinux often uses regular expressions to specify labels that
match multiple files.
The following file types are defined for passwd:
passwd_exec_t
- Set files with the passwd_exec_t type, if you want to transition an
executable to the passwd_t domain.
Paths:
/usr/bin/chage, /usr/bin/passwd
passwd_file_t
- Set files with the passwd_file_t type, if you want to treat the files
as passwd content.
Paths:
/etc/group[-+]?, /etc/passwd[-+]?, /etc/passwd.adjunct.*,
/etc/ptmptmp, /etc/.pwd.lock, /etc/group.lock, /etc/passwd.OLD,
/etc/passwd.lock
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 data‐
base. 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 pol‐
icy modules.
semanage boolean can also be used to manipulate the booleans
system-config-selinux is a GUI tool available to customize SELinux pol‐
icy settings.
AUTHOR
This manual page was auto-generated using sepolicy manpage .
SEE ALSOselinux(8), passwd(8), semanage(8), restorecon(8), chcon(1), sepol‐
icy(8) , setsebool(8)passwd 14-05-08 passwd_selinux(8)