NAME¶

chrome_sandbox_selinux - Security Enhanced Linux Policy for the chrome_sandbox processes

DESCRIPTION¶

Security-Enhanced Linux secures the chrome_sandbox processes via flexible mandatory access control.

The chrome_sandbox processes execute with the chrome_sandbox_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 chrome_sandbox_t

ENTRYPOINTS¶

The chrome_sandbox_t SELinux type can be entered via the chrome_sandbox_exec_t file type.

The default entrypoint paths for the chrome_sandbox_t domain are the following:

/opt/google/chrome[^/]*/chrome-sandbox, /usr/lib/chromium-browser/chrome-sandbox

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 chrome_sandbox policy is very flexible allowing users to setup their chrome_sandbox processes in as secure a method as possible.

The following process types are defined for chrome_sandbox:

chrome_sandbox_t, chrome_sandbox_nacl_t

Note: semanage permissive -a chrome_sandbox_t can be used to make the process type chrome_sandbox_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. chrome_sandbox policy is extremely flexible and has several booleans that allow you to manipulate the policy and run chrome_sandbox with the tightest access possible.

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 any process to mmap any file on system with attribute file_type, you must turn on the domain_can_mmap_files boolean. Enabled by default.

setsebool -P domain_can_mmap_files 1

If you want to allow all domains write to kmsg_device, while kernel is executed with systemd.log_target=kmsg parameter, you must turn on the domain_can_write_kmsg boolean. Disabled by default.

setsebool -P domain_can_write_kmsg 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 use nscd shared memory, you must turn on the nscd_use_shm boolean. Disabled by default.

setsebool -P nscd_use_shm 1

If you want to allow regular users direct dri device access, you must turn on the selinuxuser_direct_dri_enabled boolean. Enabled by default.

setsebool -P selinuxuser_direct_dri_enabled 1

If you want to allow unconfined users to transition to the chrome sandbox domains when running chrome-sandbox, you must turn on the unconfined_chrome_sandbox_transition boolean. Enabled by default.

setsebool -P unconfined_chrome_sandbox_transition 1

If you want to support ecryptfs home directories, you must turn on the use_ecryptfs_home_dirs boolean. Disabled by default.

setsebool -P use_ecryptfs_home_dirs 1

If you want to support fusefs home directories, you must turn on the use_fusefs_home_dirs boolean. Disabled by default.

setsebool -P use_fusefs_home_dirs 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

If you want to allows clients to write to the X server shared memory segments, you must turn on the xserver_clients_write_xshm boolean. Disabled by default.

setsebool -P xserver_clients_write_xshm 1

If you want to support X userspace object manager, you must turn on the xserver_object_manager boolean. Enabled by default.

setsebool -P xserver_object_manager 1

MANAGED FILES¶

The SELinux process type chrome_sandbox_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.

cgroup_t

/sys/fs/cgroup

chrome_sandbox_home_t

/home/[^/]+/.cache/chromium(/.*)?
/home/[^/]+/.cache/google-chrome(/.*)?
/home/[^/]+/.cache/google-chrome-unstable(/.*)?

chrome_sandbox_tmp_t

chrome_sandbox_tmpfs_t

home_cert_t

/root/.pki(/.*)?
/root/.cert(/.*)?
/home/[^/]+/.pki(/.*)?
/home/[^/]+/.cert(/.*)?
/home/[^/]+/.local/share/networkmanagement/certificates(/.*)?
/home/[^/]+/.kde/share/apps/networkmanagement/certificates(/.*)?

mozilla_home_t

/home/[^/]+/.lyx(/.*)?
/home/[^/]+/.java(/.*)?
/home/[^/]+/.adobe(/.*)?
/home/[^/]+/.gnash(/.*)?
/home/[^/]+/.webex(/.*)?
/home/[^/]+/.galeon(/.*)?
/home/[^/]+/.spicec(/.*)?
/home/[^/]+/.IBMERS(/.*)?
/home/[^/]+/POkemon.*(/.*)?
/home/[^/]+/.mozilla(/.*)?
/home/[^/]+/.phoenix(/.*)?
/home/[^/]+/.icedtea(/.*)?
/home/[^/]+/.netscape(/.*)?
/home/[^/]+/.quakelive(/.*)?
/home/[^/]+/.ICAClient(/.*)?
/home/[^/]+/.macromedia(/.*)?
/home/[^/]+/.thunderbird(/.*)?
/home/[^/]+/.gcjwebplugin(/.*)?
/home/[^/]+/.grl-podcasts(/.*)?
/home/[^/]+/.cache/mozilla(/.*)?
/home/[^/]+/.icedteaplugin(/.*)?
/home/[^/]+/zimbrauserdata(/.*)?
/home/[^/]+/.config/chromium(/.*)?
/home/[^/]+/.juniper_networks(/.*)?
/home/[^/]+/.cache/icedtea-web(/.*)?
/home/[^/]+/abc
/home/[^/]+/mozilla.pdf
/home/[^/]+/.gnashpluginrc

user_fonts_cache_t

/root/.fontconfig(/.*)?
/root/.fonts/auto(/.*)?
/root/.fonts.cache-.*
/home/[^/]+/.fontconfig(/.*)?
/home/[^/]+/.fonts/auto(/.*)?
/home/[^/]+/.fonts.cache-.*

user_tmp_t

/dev/shm/mono.*
/var/run/user(/.*)?
/tmp/.X11-unix(/.*)?
/tmp/.ICE-unix(/.*)?
/dev/shm/pulse-shm.*
/tmp/.X0-lock
/tmp/hsperfdata_root
/var/tmp/hsperfdata_root
/home/[^/]+/tmp
/home/[^/]+/.tmp
/tmp/gconfd-[^/]+

xserver_tmpfs_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 ls

Policy governs the access confined processes have to these files. SELinux chrome_sandbox policy is very flexible allowing users to setup their chrome_sandbox processes in as secure a method as possible.

STANDARD FILE CONTEXT

SELinux defines the file context types for the chrome_sandbox, 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 chrome_sandbox_tmpfs_t '/srv/mychrome_sandbox_content(/.*)?'
restorecon -R -v /srv/mychrome_sandbox_content

Note: SELinux often uses regular expressions to specify labels that match multiple files.

The following file types are defined for chrome_sandbox:

chrome_sandbox_exec_t

- Set files with the chrome_sandbox_exec_t type, if you want to transition an executable to the chrome_sandbox_t domain.

Paths:

/opt/google/chrome[^/]*/chrome-sandbox, /usr/lib/chromium-browser/chrome-sandbox

chrome_sandbox_home_t

- Set files with the chrome_sandbox_home_t type, if you want to store chrome sandbox files in the users home directory.

Paths:

/home/[^/]+/.cache/chromium(/.*)?, /home/[^/]+/.cache/google-chrome(/.*)?, /home/[^/]+/.cache/google-chrome-unstable(/.*)?

chrome_sandbox_nacl_exec_t

- Set files with the chrome_sandbox_nacl_exec_t type, if you want to transition an executable to the chrome_sandbox_nacl_t domain.

Paths:

/opt/google/chrome[^/]*/nacl_helper_bootstrap, /opt/google/chrome/nacl_helper_bootstrap, /usr/lib/chromium-browser/nacl_helper_bootstrap

chrome_sandbox_tmp_t

- Set files with the chrome_sandbox_tmp_t type, if you want to store chrome sandbox temporary files in the /tmp directories.

chrome_sandbox_tmpfs_t

- Set files with the chrome_sandbox_tmpfs_t type, if you want to store chrome sandbox files on a tmpfs file system.

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.

AUTHOR¶

This manual page was auto-generated using sepolicy manpage .

SEE ALSO¶

selinux(8), chrome_sandbox(8), semanage(8), restorecon(8), chcon(1), sepolicy(8) , setsebool(8), chrome_sandbox_nacl_selinux(8), chrome_sandbox_nacl_selinux(8)