+/*
+ * Copyright (c) 2013 Apple Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
+
+#include <xpc/xpc.h>
+#include <xpc/private.h>
+#include <notify.h>
+#include <tzfile.h>
+
+#include "tzlink_internal.h"
+
+static bool peer_entitled(xpc_connection_t);
+static int set_timezone(const char *);
+static int build_source_path(char *, size_t, const char *);
+static int validate_source_path(const char *);
+
+int
+main(void)
+{
+ dispatch_queue_t queue;
+ xpc_connection_t listener;
+
+ xpc_track_activity();
+
+ queue = dispatch_queue_create(TZLINK_SERVICE_NAME, NULL);
+
+ listener = xpc_connection_create_mach_service(TZLINK_SERVICE_NAME, queue, XPC_CONNECTION_MACH_SERVICE_LISTENER);
+ xpc_connection_set_event_handler(listener, ^(xpc_object_t peer) {
+ if (xpc_get_type(peer) != XPC_TYPE_CONNECTION) {
+ return;
+ }
+
+ xpc_connection_set_target_queue(peer, queue);
+ xpc_connection_set_event_handler(peer, ^(xpc_object_t request) {
+ xpc_object_t reply;
+ const char *tz;
+ int error;
+
+ if (xpc_get_type(request) != XPC_TYPE_DICTIONARY) {
+ return;
+ }
+
+ if (peer_entitled(peer)) {
+ tz = xpc_dictionary_get_string(request, TZLINK_KEY_REQUEST_TIMEZONE);
+ error = tz ? set_timezone(tz) : EINVAL;
+ } else {
+ error = EPERM;
+ }
+
+ reply = xpc_dictionary_create_reply(request);
+ xpc_dictionary_set_uint64(reply, TZLINK_KEY_REPLY_ERROR, (uint64_t)error);
+ xpc_connection_send_message(peer, reply);
+ xpc_release(reply);
+ });
+ xpc_connection_resume(peer);
+ });
+ xpc_connection_resume(listener);
+
+ dispatch_main();
+}
+
+static bool
+peer_entitled(xpc_connection_t peer)
+{
+ xpc_object_t val;
+ bool entitled;
+
+ entitled = false;
+
+ val = xpc_connection_copy_entitlement_value(peer, TZLINK_ENTITLEMENT);
+ if (val != NULL) {
+ entitled = xpc_bool_get_value(val);
+ xpc_release(val);
+ }
+
+ return entitled;
+}
+
+static int
+set_timezone(const char *tz)
+{
+ char srcpath[PATH_MAX];
+ int error;
+
+ error = build_source_path(srcpath, sizeof(srcpath), tz);
+ if (error != 0) {
+ return error;
+ }
+
+ error = validate_source_path(srcpath);
+ if (error != 0) {
+ return error;
+ }
+
+ (void)unlink(TZDEFAULT);
+ if (symlink(srcpath, TZDEFAULT) != 0) {
+ return errno ? errno : EFAULT;
+ }
+
+ /*
+ * notifyd posts "com.apple.system.timezone" automatically,
+ * but we also need post this. Sigh.
+ */
+ (void)notify_post("SignificantTimeChangeNotification");
+
+ return 0;
+}
+
+/* Create path from input. */
+static int
+build_source_path(char *path, size_t size, const char *tz)
+{
+ char *str, *str0;
+ char *pathcomp;
+ int error;
+
+ if (strlcpy(path, TZDIR, size) >= size) {
+ return ENAMETOOLONG;
+ }
+
+ error = 0;
+
+ /* Attempt to validate the input; construct a clean path as we go. */
+ str0 = str = strdup(tz);
+ while ((pathcomp = strsep(&str, "/")) != NULL) {
+ if (pathcomp[0] == '\0' || pathcomp[0] == '.') {
+ error = EINVAL;
+ break;
+ }
+ if (strlcat(path, "/", size) >= size) {
+ error = ENAMETOOLONG;
+ break;
+ }
+ if (strlcat(path, pathcomp, size) >= size) {
+ error = ENAMETOOLONG;
+ break;
+ }
+ }
+ free(str0);
+
+ return error;
+}
+
+/* Validate path. */
+static int
+validate_source_path(const char *path)
+{
+ struct stat sb;
+
+ if (lstat(path, &sb) != 0) {
+ return errno ? errno : EFAULT;
+ }
+
+ /* Ensure that the time zone file is... */
+
+ /* ... a regular file. */
+ if (!S_ISREG(sb.st_mode)) {
+ return ENOENT;
+ }
+
+ /* ... owned by root:wheel */
+ if (sb.st_uid != 0 || sb.st_gid != 0) {
+ return ENOENT;
+ }
+
+ /* ... 0644 perms */
+ if ((sb.st_mode & ACCESSPERMS) != 0644) {
+ return ENOENT;
+ }
+
+ /* ... is a real tzfile (starts with TZif) */
+ // TODO: Validate contents of file.
+
+ return 0;
+}
projects / apple / libutil.git / commitdiff
