diff --git a/prepare_dir.cpp b/prepare_dir.cpp
new file mode 100644
index 0000000..1d91458
--- /dev/null
+++ b/prepare_dir.cpp
@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Tool to create a directory with the right SELinux context applied, or
+ * apply the context if it's absent. Also fixes mode, uid, gid.
+ */
+
+#include <string>
+#include <vector>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+
+#include <android-base/logging.h>
+
+#include <cutils/fs.h>
+#include <selinux/android.h>
+
+void usage(const char* progname) {
+    fprintf(stderr, "Usage: %s --mode MODE --uid UID --gid GID -- <path>\n", progname);
+}
+
+bool small_int(const std::string& s) {
+    return !s.empty() && s.size() < 7 && s.find_first_not_of("0123456789") == std::string::npos;
+}
+
+int main(int argc, const char* const argv[]) {
+    setenv("ANDROID_LOG_TAGS", "*:v", 1);
+    android::base::InitLogging(const_cast<char**>(argv));
+    std::vector<std::string> args(argv + 1, argv + argc);
+    // Enforce exact format of arguments. You can always loosen but you can never tighten :)
+    if (args.size() != 8 || args[0] != "--mode" || !small_int(args[1]) || args[2] != "--uid" ||
+        !small_int(args[3]) || args[4] != "--gid" || !small_int(args[5]) || args[6] != "--") {
+        usage(argv[0]);
+        return -1;
+    }
+    mode_t mode = (mode_t)stoi(args[1], nullptr, 8);
+    uid_t uid = (uid_t)stoi(args[3]);
+    gid_t gid = (gid_t)stoi(args[5]);
+    const char* path = args[7].c_str();
+
+    struct selabel_handle* sehandle = selinux_android_file_context_handle();
+    char* secontext = nullptr;
+    if (sehandle) {
+        if (selabel_lookup(sehandle, &secontext, path, S_IFDIR) == 0) {
+            setfscreatecon(secontext);
+        }
+    }
+
+    if (fs_prepare_dir(path, mode, uid, gid) != 0) {
+        return -1;
+    }
+    if (secontext) {
+        char* oldsecontext = nullptr;
+        if (lgetfilecon(path, &oldsecontext) < 0) {
+            PLOG(ERROR) << "Unable to read secontext for: " << path;
+            return -1;
+        }
+        if (strcmp(secontext, oldsecontext) != 0) {
+            LOG(INFO) << "Relabelling from " << oldsecontext << " to " << secontext << ": " << path;
+            if (lsetfilecon(path, secontext) != 0) {
+                PLOG(ERROR) << "Relabelling failed for: " << path;
+            }
+        }
+    }
+    return 0;
+}