diff --git a/VoldNativeServiceValidation.cpp b/VoldNativeServiceValidation.cpp
new file mode 100644
index 0000000..2e21ace
--- /dev/null
+++ b/VoldNativeServiceValidation.cpp
@@ -0,0 +1,109 @@
+/*
+ * Copyright (C) 2020 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.
+ */
+
+#include "VoldNativeServiceValidation.h"
+
+#include <android-base/stringprintf.h>
+#include <android-base/strings.h>
+#include <binder/IPCThreadState.h>
+#include <binder/IServiceManager.h>
+#include <private/android_filesystem_config.h>
+
+#include <cctype>
+#include <string_view>
+
+using android::base::StringPrintf;
+using namespace std::literals;
+
+namespace android::vold {
+
+binder::Status Ok() {
+    return binder::Status::ok();
+}
+
+binder::Status Exception(uint32_t code, const std::string& msg) {
+    return binder::Status::fromExceptionCode(code, String8(msg.c_str()));
+}
+
+binder::Status CheckPermission(const char* permission) {
+    pid_t pid;
+    uid_t uid;
+
+    if (checkCallingPermission(String16(permission), reinterpret_cast<int32_t*>(&pid),
+                               reinterpret_cast<int32_t*>(&uid))) {
+        return Ok();
+    } else {
+        return Exception(binder::Status::EX_SECURITY,
+                         StringPrintf("UID %d / PID %d lacks permission %s", uid, pid, permission));
+    }
+}
+
+binder::Status CheckUidOrRoot(uid_t expectedUid) {
+    uid_t uid = IPCThreadState::self()->getCallingUid();
+    if (uid == expectedUid || uid == AID_ROOT) {
+        return Ok();
+    } else {
+        return Exception(binder::Status::EX_SECURITY,
+                         StringPrintf("UID %d is not expected UID %d", uid, expectedUid));
+    }
+}
+
+binder::Status CheckArgumentId(const std::string& id) {
+    if (id.empty()) {
+        return Exception(binder::Status::EX_ILLEGAL_ARGUMENT, "Missing ID");
+    }
+    for (const char& c : id) {
+        if (!std::isalnum(c) && c != ':' && c != ',' && c != ';') {
+            return Exception(binder::Status::EX_ILLEGAL_ARGUMENT,
+                             StringPrintf("ID %s is malformed", id.c_str()));
+        }
+    }
+    return Ok();
+}
+
+binder::Status CheckArgumentPath(const std::string& path) {
+    if (path.empty()) {
+        return Exception(binder::Status::EX_ILLEGAL_ARGUMENT, "Missing path");
+    }
+    if (path[0] != '/') {
+        return Exception(binder::Status::EX_ILLEGAL_ARGUMENT,
+                         StringPrintf("Path %s is relative", path.c_str()));
+    }
+    if (path.find("/../"sv) != path.npos || android::base::EndsWith(path, "/.."sv)) {
+        return Exception(binder::Status::EX_ILLEGAL_ARGUMENT,
+                         StringPrintf("Path %s is shady", path.c_str()));
+    }
+    for (const char& c : path) {
+        if (c == '\0' || c == '\n') {
+            return Exception(binder::Status::EX_ILLEGAL_ARGUMENT,
+                             StringPrintf("Path %s is malformed", path.c_str()));
+        }
+    }
+    return Ok();
+}
+
+binder::Status CheckArgumentHex(const std::string& hex) {
+    // Empty hex strings are allowed
+    for (const char& c : hex) {
+        if (!std::isxdigit(c) && c != ':' && c != '-') {
+            return Exception(binder::Status::EX_ILLEGAL_ARGUMENT,
+                             StringPrintf("Hex %s is malformed", hex.c_str()));
+        }
+    }
+    return Ok();
+}
+
+}  // namespace android::vold