###############################################################################

#

# Copyright (C) 2006, 2010 Red Hat, Inc. All Rights Reserved.

# Written by David Howells (dhowells@redhat.com)

#            Karl MacMillan (kmacmill@redhat.com)

#

# This program is free software; you can redistribute it and/or

# modify it under the terms of the GNU General Public License

# as published by the Free Software Foundation; either version

# 2 of the License, or (at your option) any later version.

#

###############################################################################

#

# This security policy governs access by the CacheFiles kernel module and

# userspace management daemon to the files and directories in the on-disk

# cache, on behalf of the processes accessing the cache through a network

# filesystem such as NFS

#

policy_module(cachefilesd,1.0.17)

###############################################################################

#

# Declarations

#

#

# Files in the cache are created by the cachefiles module with security ID

# cachefiles_var_t

#

type cachefiles_var_t;

files_type(cachefiles_var_t)

#

# The /dev/cachefiles character device has security ID cachefiles_dev_t

#

type cachefiles_dev_t;

dev_node(cachefiles_dev_t)

#

# The cachefilesd daemon normally runs with security ID cachefilesd_t

#

type cachefilesd_t;

type cachefilesd_exec_t;

domain_type(cachefilesd_t)

init_daemon_domain(cachefilesd_t, cachefilesd_exec_t)

#

# The cachefilesd daemon pid file context

#

type cachefilesd_var_run_t;

files_pid_file(cachefilesd_var_run_t)

#

# The CacheFiles kernel module causes processes accessing the cache files to do

# so acting as security ID cachefiles_kernel_t

#

type cachefiles_kernel_t;

domain_type(cachefiles_kernel_t)

domain_obj_id_change_exemption(cachefiles_kernel_t)

role system_r types cachefiles_kernel_t;

###############################################################################

#

# Permit RPM to deal with files in the cache

#

rpm_use_script_fds(cachefilesd_t)

###############################################################################

#

# cachefilesd local policy

#

# These define what cachefilesd is permitted to do.  This doesn't include very

# much: startup stuff, logging, pid file, scanning the cache superstructure and

# deleting files from the cache.  It is not permitted to read/write files in

# the cache.

#

# Check in /usr/share/selinux/devel/include/ for macros to use instead of allow

# rules.

#

allow cachefilesd_t self : capability { setuid setgid sys_admin dac_override };

# Basic access

files_read_etc_files(cachefilesd_t)

libs_use_ld_so(cachefilesd_t)

libs_use_shared_libs(cachefilesd_t)

miscfiles_read_localization(cachefilesd_t)

logging_send_syslog_msg(cachefilesd_t)

init_dontaudit_use_script_ptys(cachefilesd_t)

term_dontaudit_use_generic_ptys(cachefilesd_t)

term_dontaudit_getattr_unallocated_ttys(cachefilesd_t)

# Allow manipulation of pid file

allow cachefilesd_t cachefilesd_var_run_t:file create_file_perms;

manage_files_pattern(cachefilesd_t,cachefilesd_var_run_t, cachefilesd_var_run_t)

manage_dirs_pattern(cachefilesd_t,cachefilesd_var_run_t, cachefilesd_var_run_t)

files_pid_file(cachefilesd_var_run_t)

files_pid_filetrans(cachefilesd_t,cachefilesd_var_run_t,file)

files_create_as_is_all_files(cachefilesd_t)

# Allow access to cachefiles device file

allow cachefilesd_t cachefiles_dev_t : chr_file rw_file_perms;

# Allow access to cache superstructure

allow cachefilesd_t cachefiles_var_t : dir { rw_dir_perms rmdir };

allow cachefilesd_t cachefiles_var_t : file { getattr rename unlink };

# Permit statfs on the backing filesystem

fs_getattr_xattr_fs(cachefilesd_t)

###############################################################################

#

# When cachefilesd invokes the kernel module to begin caching, it has to tell

# the kernel module the security context in which it should act, and this

# policy has to approve that.

#

# There are two parts to this:

#

#   (1) the security context used by the module to access files in the cache,

#       as set by the 'secctx' command in /etc/cachefilesd.conf, and

#

allow cachefilesd_t cachefiles_kernel_t : kernel_service { use_as_override };

#

#   (2) the label that will be assigned to new files and directories created in

#       the cache by the module, which will be the same as the label on the

#       directory pointed to by the 'dir' command.

#

allow cachefilesd_t cachefiles_var_t : kernel_service { create_files_as };

###############################################################################

#

# cachefiles kernel module local policy

#

# This governs what the kernel module is allowed to do the contents of the

# cache.

#

allow cachefiles_kernel_t self:capability { dac_override dac_read_search };

allow cachefiles_kernel_t initrc_t:process sigchld;

manage_dirs_pattern(cachefiles_kernel_t,cachefiles_var_t, cachefiles_var_t)

manage_files_pattern(cachefiles_kernel_t,cachefiles_var_t, cachefiles_var_t)

fs_getattr_xattr_fs(cachefiles_kernel_t)

dev_search_sysfs(cachefiles_kernel_t)