busybox/libbb/selinux_common.c

/*
 * libbb/selinux_common.c
 *   -- common SELinux utility functions
 *
 * Copyright 2007 KaiGai Kohei <kaigai@kaigai.gr.jp>
 *
 * Licensed under GPLv2, see file LICENSE in this source tree.
 */
#include "libbb.h"
#include <selinux/context.h>

context_t FAST_FUNC set_security_context_component(security_context_t cur_context,
			char *user, char *role, char *type, char *range)
{
	context_t con = context_new(cur_context);
	if (!con)
		return NULL;

	if (user && context_user_set(con, user))
		goto error;
	if (type && context_type_set(con, type))
		goto error;
	if (range && context_range_set(con, range))
		goto error;
	if (role && context_role_set(con, role))
		goto error;
	return con;

error:
	context_free(con);
	return NULL;
}

void FAST_FUNC setfscreatecon_or_die(security_context_t scontext)
{
	if (setfscreatecon(scontext) < 0) {
		/* Can be NULL. All known printf implementations
		 * display "(null)", "<null>" etc */
		bb_perror_msg_and_die("can't set default "
				"file creation context to %s", scontext);
	}
}

void FAST_FUNC selinux_preserve_fcontext(int fdesc)
{
	security_context_t context;

	if (fgetfilecon(fdesc, &context) < 0) {
		if (errno == ENODATA || errno == ENOTSUP)
			return;
		bb_simple_perror_msg_and_die("fgetfilecon failed");
	}
	setfscreatecon_or_die(context);
	freecon(context);
}