diff --git a/identity/aidl/default/Util.h b/identity/aidl/default/Util.h
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+++ b/identity/aidl/default/Util.h
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+/*
+ * Copyright 2019, 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.
+ */
+
+#ifndef ANDROID_HARDWARE_IDENTITY_UTIL_H
+#define ANDROID_HARDWARE_IDENTITY_UTIL_H
+
+#include <aidl/android/hardware/identity/BnIdentityCredential.h>
+#include <android/hardware/identity/support/IdentityCredentialSupport.h>
+
+#include <map>
+#include <optional>
+#include <set>
+#include <string>
+#include <vector>
+
+#include <cppbor/cppbor.h>
+
+namespace aidl::android::hardware::identity {
+
+using ::std::optional;
+using ::std::string;
+using ::std::vector;
+
+// Returns the hardware-bound AES-128 key.
+const vector<uint8_t>& getHardwareBoundKey();
+
+// Calculates the MAC for |profile| using |storageKey|.
+optional<vector<uint8_t>> secureAccessControlProfileCalcMac(
+        const SecureAccessControlProfile& profile, const vector<uint8_t>& storageKey);
+
+// Checks authenticity of the MAC in |profile| using |storageKey|.
+bool secureAccessControlProfileCheckMac(const SecureAccessControlProfile& profile,
+                                        const vector<uint8_t>& storageKey);
+
+// Creates the AdditionalData CBOR used in the addEntryValue() HIDL method.
+vector<uint8_t> entryCreateAdditionalData(const string& nameSpace, const string& name,
+                                          const vector<int32_t> accessControlProfileIds);
+
+vector<uint8_t> byteStringToUnsigned(const vector<int8_t>& value);
+
+vector<int8_t> byteStringToSigned(const vector<uint8_t>& value);
+
+}  // namespace aidl::android::hardware::identity
+
+#endif  // ANDROID_HARDWARE_IDENTITY_UTIL_H