SELinux xscreensaver policy support

Hello

This a patch for adding xscreensaver policy.

I think it need a specific policy because of the auth_domtrans_chk_passwd.

cordially

Signed-off-by: LABBE Corentin <corentin.labbe@geomatys.fr>

policy/modules/apps/xscreensaver.fc

@@ -0,0 +1 @@
+/usr/bin/xscreensaver	-- gen_context(system_u:object_r:xscreensaver_exec_t,s0)

policy/modules/apps/xscreensaver.if

@@ -0,0 +1,34 @@
+## <summary>xscreensaver policy interface</summary>
+
+########################################
+## <summary>
+##	Role access for xscreensaver
+## </summary>
+## <param name="role">
+##	<summary>
+##	Role allowed access
+##	</summary>
+## </param>
+## <param name="domain">
+##	<summary>
+##	User domain for the role
+##	</summary>
+## </param>
+#
+interface(`xscreensaver_role',`
+	gen_require(`
+		type xscreensaver_t, xscreensaver_exec_t;
+	')
+
+	role $1 types xscreensaver_t;
+
+	domtrans_pattern($2, xscreensaver_exec_t, xscreensaver_t)
+
+	allow xscreensaver_t $2:fd use;
+
+	# Allow the user domain to signal/ps.
+	ps_process_pattern($2, xscreensaver_t)
+	allow $2 xscreensaver_t:process signal_perms;
+	allow xscreensaver_t $2:process sigchld;
+
+')

policy/modules/apps/xscreensaver.te

@@ -0,0 +1,52 @@
+policy_module(xscreensaver, 1.0.0)
+
+########################################
+#
+# Declarations
+#
+
+type xscreensaver_t;
+type xscreensaver_exec_t;
+application_domain(xscreensaver_t, xscreensaver_exec_t)
+
+type xscreensaver_tmpfs_t;
+files_tmpfs_file(xscreensaver_tmpfs_t)
+ubac_constrained(xscreensaver_tmpfs_t)
+
+########################################
+#
+# Local policy
+#
+auth_use_nsswitch(xscreensaver_t)
+
+logging_send_audit_msgs(xscreensaver_t)
+logging_send_syslog_msg(xscreensaver_t)
+miscfiles_read_localization(xscreensaver_t)
+
+allow xscreensaver_t self:fifo_file rw_fifo_file_perms;
+allow xscreensaver_t self:process signal;
+
+#access to .icons and ~/.xscreensaver
+userdom_read_user_home_content_files(xscreensaver_t)
+
+userdom_use_user_ptys(xscreensaver_t)
+
+files_read_usr_files(xscreensaver_t)
+
+auth_domtrans_chk_passwd(xscreensaver_t)
+
+#/var/run/utmp
+init_read_utmp(xscreensaver_t)
+
+########################################
+#
+# X Serveur and co
+#
+xserver_user_x_domain_template(xscreensaver, xscreensaver_t, xscreensaver_tmpfs_t)
+
+########################################
+#
+# process, kernel and /proc /dev /sys
+#
+
+kernel_read_system_state(xscreensaver_t)