diff --git a/keystore-engine/Android.mk b/keystore-engine/Android.mk
index e65e011..e182dbd 100644
--- a/keystore-engine/Android.mk
+++ b/keystore-engine/Android.mk
@@ -24,6 +24,7 @@
 
 LOCAL_MODULE_TAGS := optional
 LOCAL_CFLAGS := -fvisibility=hidden -Wall -Werror
+LOCAL_CPPFLAGS += -std=c++17
 
 LOCAL_SHARED_LIBRARIES += \
 	libbinder \
@@ -53,6 +54,7 @@
 
 LOCAL_MODULE_TAGS := optional
 LOCAL_CFLAGS := -fvisibility=hidden -Wall -Werror -DBACKEND_WIFI_HIDL
+LOCAL_CPPFLAGS += -std=c++17
 
 LOCAL_SHARED_LIBRARIES += \
 	android.system.wifi.keystore@1.0 \
diff --git a/keystore-engine/android_engine.cpp b/keystore-engine/android_engine.cpp
index fba2583..856194d 100644
--- a/keystore-engine/android_engine.cpp
+++ b/keystore-engine/android_engine.cpp
@@ -80,8 +80,7 @@
  * the argument on failure. This means we need to tell our scoped pointers when
  * we've transferred ownership, without triggering a warning by not using the
  * result of release(). */
-#define OWNERSHIP_TRANSFERRED(obj) \
-    typeof ((obj).release()) _dummy __attribute__((unused)) = (obj).release()
+#define OWNERSHIP_TRANSFERRED(obj) auto _dummy __attribute__((unused)) = (obj).release()
 
 const char* rsa_get_key_id(const RSA* rsa);
 
diff --git a/keystore-engine/keystore_backend_binder.cpp b/keystore-engine/keystore_backend_binder.cpp
index cd407c8..0e38b50 100644
--- a/keystore-engine/keystore_backend_binder.cpp
+++ b/keystore-engine/keystore_backend_binder.cpp
@@ -23,18 +23,22 @@
 #include "keystore_backend_binder.h"
 
 #include <android-base/logging.h>
-#include <android/security/IKeystoreService.h>
+#include <android/security/keystore/IKeystoreService.h>
 #include <binder/IServiceManager.h>
 #include <keystore/KeyCharacteristics.h>
 #include <keystore/KeymasterArguments.h>
 #include <keystore/KeymasterBlob.h>
+#include <keystore/KeystoreResponse.h>
 #include <keystore/OperationResult.h>
 #include <keystore/keymaster_types.h>
 #include <keystore/keystore.h>
 #include <keystore/keystore_hidl_support.h>
+#include <keystore/keystore_promises.h>
 #include <keystore/keystore_return_types.h>
 
-using android::security::IKeystoreService;
+#include <future>
+
+using android::security::keystore::IKeystoreService;
 using namespace android;
 using keystore::hidl_vec;
 
@@ -60,7 +64,13 @@
 namespace {
 const char keystore_service_name[] = "android.security.keystore";
 constexpr int32_t UID_SELF = -1;
-};
+
+using keystore::KeyCharacteristicsPromise;
+using keystore::KeystoreExportPromise;
+using keystore::KeystoreResponsePromise;
+using keystore::OperationResultPromise;
+
+}  // namespace
 
 #define AT __func__ << ":" << __LINE__ << " "
 
@@ -88,20 +98,29 @@
         return -1;
     }
 
-    KeyCharacteristics keyCharacteristics;
     String16 key_name16(key_id);
-    int32_t aidl_result;
-    auto binder_result = service->getKeyCharacteristics(
-        key_name16, KeymasterBlob(), KeymasterBlob(), UID_SELF, &keyCharacteristics, &aidl_result);
+    int32_t error_code;
+    android::sp<KeyCharacteristicsPromise> kc_promise(new KeyCharacteristicsPromise);
+    auto kc_future = kc_promise->get_future();
+    auto binder_result = service->getKeyCharacteristics(kc_promise, key_name16, KeymasterBlob(),
+                                                        KeymasterBlob(), UID_SELF, &error_code);
     if (!binder_result.isOk()) {
         LOG(ERROR) << AT << "communication error while calling keystore";
         return -1;
     }
-    if (KSReturn(aidl_result).isOk()) {
-        LOG(ERROR) << AT << "getKeyCharacteristics failed: " << aidl_result;
+    if (KSReturn(error_code).isOk()) {
+        LOG(ERROR) << AT << "getKeyCharacteristics failed: " << error_code;
+        return -1;
     }
 
-    auto algorithm = getKeyAlgoritmFromKeyCharacteristics(keyCharacteristics);
+    auto [km_response, characteristics] = kc_future.get();
+
+    if (KSReturn(km_response.response_code()).isOk()) {
+        LOG(ERROR) << AT << "getKeyCharacteristics failed: " << km_response.response_code();
+        return -1;
+    }
+
+    auto algorithm = getKeyAlgoritmFromKeyCharacteristics(characteristics);
     if (!algorithm.isOk()) {
         LOG(ERROR) << AT << "could not get algorithm from key characteristics";
         return -1;
@@ -113,14 +132,23 @@
     params[2] = Authorization(TAG_ALGORITHM, algorithm.value());
 
     android::sp<android::IBinder> token(new android::BBinder);
-    OperationResult result;
-    binder_result = service->begin(token, key_name16, (int)KeyPurpose::SIGN, true /*pruneable*/,
-                                   KeymasterArguments(params), std::vector<uint8_t>() /* entropy */,
-                                   UID_SELF, &result);
+    sp<OperationResultPromise> promise(new OperationResultPromise());
+    auto future = promise->get_future();
+    binder_result = service->begin(promise, token, key_name16, (int)KeyPurpose::SIGN,
+                                   true /*pruneable*/, KeymasterArguments(params),
+                                   std::vector<uint8_t>() /* entropy */, UID_SELF, &error_code);
     if (!binder_result.isOk()) {
         LOG(ERROR) << AT << "communication error while calling keystore";
         return -1;
     }
+
+    keystore::KeyStoreNativeReturnCode rc(error_code);
+    if (!rc.isOk()) {
+        LOG(ERROR) << AT << "Keystore begin returned: " << error_code;
+        return -1;
+    }
+    OperationResult result = future.get();
+
     if (!result.resultCode.isOk()) {
         LOG(ERROR) << AT << "begin failed: " << int32_t(result.resultCode);
         return -1;
@@ -128,32 +156,71 @@
     auto handle = std::move(result.token);
 
     do {
-        binder_result = service->update(handle, KeymasterArguments(params),
-                                        std::vector<uint8_t>(in, in + len), &result);
+        future = {};
+        promise = new OperationResultPromise();
+        future = promise->get_future();
+        binder_result = service->update(promise, handle, KeymasterArguments(params),
+                                        std::vector<uint8_t>(in, in + len), &error_code);
         if (!binder_result.isOk()) {
             LOG(ERROR) << AT << "communication error while calling keystore";
             return -1;
         }
+
+        rc = keystore::KeyStoreNativeReturnCode(error_code);
+        if (!rc.isOk()) {
+            LOG(ERROR) << AT << "Keystore update returned: " << error_code;
+            return -1;
+        }
+        result = future.get();
+
         if (!result.resultCode.isOk()) {
             LOG(ERROR) << AT << "update failed: " << int32_t(result.resultCode);
             return -1;
         }
+
         if (result.inputConsumed > len) {
             LOG(ERROR) << AT << "update consumed more data than provided";
-            service->abort(handle, &aidl_result);
+            sp<KeystoreResponsePromise> abortPromise(new KeystoreResponsePromise);
+            auto abortFuture = abortPromise->get_future();
+            binder_result = service->abort(abortPromise, handle, &error_code);
+            if (!binder_result.isOk()) {
+                LOG(ERROR) << AT << "communication error while calling keystore";
+                return -1;
+            }
+            // This is mainly for logging since we already failed.
+            // But if abort returned OK we have to wait untill abort calls the callback
+            // hence the call to abortFuture.get().
+            if (!KSReturn(error_code).isOk()) {
+                LOG(ERROR) << AT << "abort failed: " << error_code;
+            } else if (!(rc = KSReturn(abortFuture.get().response_code())).isOk()) {
+                LOG(ERROR) << AT << "abort failed: " << int32_t(rc);
+            }
             return -1;
         }
         len -= result.inputConsumed;
         in += result.inputConsumed;
     } while (len > 0);
 
-    binder_result =
-        service->finish(handle, KeymasterArguments(params), std::vector<uint8_t>() /* signature */,
-                        std::vector<uint8_t>() /* entropy */, &result);
+    future = {};
+    promise = new OperationResultPromise();
+    future = promise->get_future();
+
+    binder_result = service->finish(promise, handle, KeymasterArguments(params),
+                                    std::vector<uint8_t>() /* signature */,
+                                    std::vector<uint8_t>() /* entropy */, &error_code);
+
     if (!binder_result.isOk()) {
         LOG(ERROR) << AT << "communication error while calling keystore";
         return -1;
     }
+
+    rc = keystore::KeyStoreNativeReturnCode(error_code);
+    if (!rc.isOk()) {
+        LOG(ERROR) << AT << "Keystore finish returned: " << error_code;
+        return -1;
+    }
+    result = future.get();
+
     if (!result.resultCode.isOk()) {
         LOG(ERROR) << AT << "finish failed: " << int32_t(result.resultCode);
         return -1;
@@ -180,25 +247,34 @@
         return -1;
     }
 
-    ExportResult result;
-    auto binder_result = service->exportKey(String16(key_id), static_cast<int32_t>(KeyFormat::X509),
-                                            KeymasterBlob() /* clientId */,
-                                            KeymasterBlob() /* appData */, UID_SELF, &result);
+    int32_t error_code;
+    android::sp<KeystoreExportPromise> promise(new KeystoreExportPromise);
+    auto future = promise->get_future();
+    auto binder_result = service->exportKey(
+        promise, String16(key_id), static_cast<int32_t>(KeyFormat::X509),
+        KeymasterBlob() /* clientId */, KeymasterBlob() /* appData */, UID_SELF, &error_code);
     if (!binder_result.isOk()) {
         LOG(ERROR) << AT << "communication error while calling keystore";
         return -1;
     }
-    if (!result.resultCode.isOk()) {
-        LOG(ERROR) << AT << "exportKey failed: " << int32_t(result.resultCode);
+
+    KSReturn rc(error_code);
+    if (!rc.isOk()) {
+        LOG(ERROR) << AT << "exportKey failed: " << error_code;
         return -1;
     }
 
-    hidl_vec<uint8_t> reply_hidl(result.exportData);
+    auto export_result = future.get();
+    if (!export_result.resultCode.isOk()) {
+        LOG(ERROR) << AT << "exportKey failed: " << int32_t(export_result.resultCode);
+        return -1;
+    }
+
     if (pubkey_len) {
-        *pubkey_len = reply_hidl.size();
+        *pubkey_len = export_result.exportData.size();
     }
     if (pubkey) {
-        *pubkey = reply_hidl.releaseData();
+        *pubkey = export_result.exportData.releaseData();
     }
     return 0;
 }
diff --git a/keystore/Android.bp b/keystore/Android.bp
index 1168e90..295d605 100644
--- a/keystore/Android.bp
+++ b/keystore/Android.bp
@@ -139,10 +139,10 @@
         "KeyAttestationApplicationId.cpp",
         "KeyAttestationPackageInfo.cpp",
         "KeymasterArguments.cpp",
-        "KeystoreArguments.cpp",
+        "keystore_aidl_hidl_marshalling_utils.cpp",
+        "KeystoreResponse.cpp",
         "OperationResult.cpp",
         "Signature.cpp",
-        "keystore_aidl_hidl_marshalling_utils.cpp",
     ],
     shared_libs: [
         "android.hardware.keymaster@4.0",
@@ -269,7 +269,12 @@
     name: "keystore_aidl",
     srcs: [
         "binder/android/security/IConfirmationPromptCallback.aidl",
-        "binder/android/security/IKeystoreService.aidl",
+        "binder/android/security/keystore/IKeystoreCertificateChainCallback.aidl",
+        "binder/android/security/keystore/IKeystoreExportKeyCallback.aidl",
+        "binder/android/security/keystore/IKeystoreKeyCharacteristicsCallback.aidl",
+        "binder/android/security/keystore/IKeystoreOperationResultCallback.aidl",
+        "binder/android/security/keystore/IKeystoreResponseCallback.aidl",
+        "binder/android/security/keystore/IKeystoreService.aidl",
     ],
     path: "binder",
 }
diff --git a/keystore/KeyStore.cpp b/keystore/KeyStore.cpp
index 8c4844f..7530243 100644
--- a/keystore/KeyStore.cpp
+++ b/keystore/KeyStore.cpp
@@ -28,7 +28,7 @@
 
 #include <android-base/scopeguard.h>
 #include <android/hardware/keymaster/3.0/IKeymasterDevice.h>
-#include <android/security/IKeystoreService.h>
+#include <android/security/keystore/IKeystoreService.h>
 #include <log/log_event_list.h>
 
 #include <private/android_logger.h>
diff --git a/keystore/KeystoreArguments.cpp b/keystore/KeystoreArguments.cpp
deleted file mode 100644
index 6b29e78..0000000
--- a/keystore/KeystoreArguments.cpp
+++ /dev/null
@@ -1,61 +0,0 @@
-/*
-**
-** Copyright 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.
-*/
-
-#include "include/keystore/KeystoreArguments.h"
-#include "keystore_aidl_hidl_marshalling_utils.h"
-
-#include <binder/Parcel.h>
-
-namespace android {
-namespace security {
-
-using ::android::security::KeystoreArg;
-using ::android::security::KeystoreArguments;
-
-const ssize_t MAX_GENERATE_ARGS = 3;
-status_t KeystoreArguments::readFromParcel(const android::Parcel* in) {
-    ssize_t numArgs = in->readInt32();
-    if (numArgs > MAX_GENERATE_ARGS) {
-        return BAD_VALUE;
-    }
-    if (numArgs > 0) {
-        for (size_t i = 0; i < static_cast<size_t>(numArgs); i++) {
-            ssize_t inSize = in->readInt32();
-            if (inSize >= 0 && static_cast<size_t>(inSize) <= in->dataAvail()) {
-                sp<KeystoreArg> arg = new KeystoreArg(in->readInplace(inSize), inSize);
-                args.push_back(arg);
-            } else {
-                args.push_back(nullptr);
-            }
-        }
-    }
-    return OK;
-};
-
-status_t KeystoreArguments::writeToParcel(android::Parcel* out) const {
-    out->writeInt32(args.size());
-    for (sp<KeystoreArg> item : args) {
-        size_t keyLength = item->size();
-        out->writeInt32(keyLength);
-        void* buf = out->writeInplace(keyLength);
-        memcpy(buf, item->data(), keyLength);
-    }
-    return OK;
-}
-
-}  // namespace security
-}  // namespace android
diff --git a/keystore/KeystoreResponse.cpp b/keystore/KeystoreResponse.cpp
new file mode 100644
index 0000000..c46973a
--- /dev/null
+++ b/keystore/KeystoreResponse.cpp
@@ -0,0 +1,43 @@
+/*
+**
+** Copyright 2018, 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 <binder/Parcel.h>
+#include <keystore/keymaster_types.h>
+#include <utility>
+#include <utils/String16.h>
+
+#include "include/keystore/KeystoreResponse.h"
+
+namespace android {
+namespace security {
+namespace keystore {
+
+status_t KeystoreResponse::readFromParcel(const Parcel* in) {
+    auto rc = in->readInt32(&response_code_);
+    if (rc != NO_ERROR) return rc;
+    return in->readString16(&error_msg_);
+}
+
+status_t KeystoreResponse::writeToParcel(Parcel* out) const {
+    auto rc = out->writeInt32(response_code_);
+    if (rc != NO_ERROR) return rc;
+    return out->writeString16(error_msg_);
+}
+
+}  // namespace keystore
+}  // namespace security
+}  // namespace android
diff --git a/keystore/binder/android/security/IKeystoreService.aidl b/keystore/binder/android/security/IKeystoreService.aidl
deleted file mode 100644
index c490eda..0000000
--- a/keystore/binder/android/security/IKeystoreService.aidl
+++ /dev/null
@@ -1,82 +0,0 @@
-/**
- * Copyright (c) 2015, 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.
- */
-
-package android.security;
-
-import android.security.keymaster.ExportResult;
-import android.security.keymaster.KeyCharacteristics;
-import android.security.keymaster.KeymasterArguments;
-import android.security.keymaster.KeymasterCertificateChain;
-import android.security.keymaster.KeymasterBlob;
-import android.security.keymaster.OperationResult;
-import android.security.KeystoreArguments;
-
-/**
- * This must be kept manually in sync with system/security/keystore until AIDL
- * can generate both Java and C++ bindings.
- *
- * @hide
- */
-interface IKeystoreService {
-    int getState(int userId);
-    byte[] get(String name, int uid);
-    int insert(String name, in byte[] item, int uid, int flags);
-    int del(String name, int uid);
-    int exist(String name, int uid);
-    String[] list(String namePrefix, int uid);
-    int reset();
-    int onUserPasswordChanged(int userId, String newPassword);
-    int lock(int userId);
-    int unlock(int userId, String userPassword);
-    int isEmpty(int userId);
-    String grant(String name, int granteeUid);
-    int ungrant(String name, int granteeUid);
-    long getmtime(String name, int uid);
-    int is_hardware_backed(String string);
-    int clear_uid(long uid);
-
-    // Keymaster 0.4 methods
-    int addRngEntropy(in byte[] data, int flags);
-    int generateKey(String alias, in KeymasterArguments arguments, in byte[] entropy, int uid,
-        int flags, out KeyCharacteristics characteristics);
-    int getKeyCharacteristics(String alias, in KeymasterBlob clientId, in KeymasterBlob appData,
-        int uid, out KeyCharacteristics characteristics);
-    int importKey(String alias, in KeymasterArguments arguments, int format,
-        in byte[] keyData, int uid, int flags, out KeyCharacteristics characteristics);
-    ExportResult exportKey(String alias, int format, in KeymasterBlob clientId,
-        in KeymasterBlob appData, int uid);
-    OperationResult begin(IBinder appToken, String alias, int purpose, boolean pruneable,
-        in KeymasterArguments params, in byte[] entropy, int uid);
-    OperationResult update(IBinder token, in KeymasterArguments params, in byte[] input);
-    OperationResult finish(IBinder token, in KeymasterArguments params, in byte[] signature,
-        in byte[] entropy);
-    int abort(IBinder handle);
-    int addAuthToken(in byte[] authToken);
-    int onUserAdded(int userId, int parentId);
-    int onUserRemoved(int userId);
-    int attestKey(String alias, in KeymasterArguments params, out KeymasterCertificateChain chain);
-    int attestDeviceIds(in KeymasterArguments params, out KeymasterCertificateChain chain);
-    int onDeviceOffBody();
-    int importWrappedKey(in String wrappedKeyAlias, in byte[] wrappedKey,
-        in String wrappingKeyAlias, in byte[] maskingKey, in KeymasterArguments arguments,
-        in long rootSid, in long fingerprintSid,
-        out KeyCharacteristics characteristics);
-    int presentConfirmationPrompt(IBinder listener, String promptText, in byte[] extraData,
-        in String locale, in int uiOptionsAsFlags);
-    int cancelConfirmationPrompt(IBinder listener);
-    boolean isConfirmationPromptSupported();
-    int onKeyguardVisibilityChanged(in boolean isShowing, in int userId);
-}
diff --git a/keystore/binder/android/security/KeystoreArguments.aidl b/keystore/binder/android/security/keystore/IKeystoreCertificateChainCallback.aidl
similarity index 60%
copy from keystore/binder/android/security/KeystoreArguments.aidl
copy to keystore/binder/android/security/keystore/IKeystoreCertificateChainCallback.aidl
index dc8ed50..dca928d 100644
--- a/keystore/binder/android/security/KeystoreArguments.aidl
+++ b/keystore/binder/android/security/keystore/IKeystoreCertificateChainCallback.aidl
@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2015, The Android Open Source Project
+ * Copyright (c) 2018, 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.
@@ -14,7 +14,14 @@
  * limitations under the License.
  */
 
-package android.security;
+package android.security.keystore;
 
-/* @hide */
-parcelable KeystoreArguments cpp_header "keystore/KeystoreArguments.h";
+import android.security.keystore.KeystoreResponse;
+import android.security.keymaster.KeymasterCertificateChain;
+
+/**
+ * @hide
+ */
+oneway interface IKeystoreCertificateChainCallback {
+    void onFinished(in KeystoreResponse response, in KeymasterCertificateChain chain);
+}
\ No newline at end of file
diff --git a/keystore/binder/android/security/KeystoreArguments.aidl b/keystore/binder/android/security/keystore/IKeystoreExportKeyCallback.aidl
similarity index 65%
copy from keystore/binder/android/security/KeystoreArguments.aidl
copy to keystore/binder/android/security/keystore/IKeystoreExportKeyCallback.aidl
index dc8ed50..e42e927 100644
--- a/keystore/binder/android/security/KeystoreArguments.aidl
+++ b/keystore/binder/android/security/keystore/IKeystoreExportKeyCallback.aidl
@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2015, The Android Open Source Project
+ * Copyright (c) 2018, 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.
@@ -14,7 +14,14 @@
  * limitations under the License.
  */
 
-package android.security;
+package android.security.keystore;
 
-/* @hide */
-parcelable KeystoreArguments cpp_header "keystore/KeystoreArguments.h";
+import android.security.keystore.KeystoreResponse;
+import android.security.keymaster.ExportResult;
+
+/**
+ * @hide
+ */
+oneway interface IKeystoreExportKeyCallback {
+	void onFinished(in ExportResult result);
+}
\ No newline at end of file
diff --git a/keystore/binder/android/security/KeystoreArguments.aidl b/keystore/binder/android/security/keystore/IKeystoreKeyCharacteristicsCallback.aidl
similarity index 61%
copy from keystore/binder/android/security/KeystoreArguments.aidl
copy to keystore/binder/android/security/keystore/IKeystoreKeyCharacteristicsCallback.aidl
index dc8ed50..e1f0ffe 100644
--- a/keystore/binder/android/security/KeystoreArguments.aidl
+++ b/keystore/binder/android/security/keystore/IKeystoreKeyCharacteristicsCallback.aidl
@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2015, The Android Open Source Project
+ * Copyright (c) 2018, 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.
@@ -14,7 +14,14 @@
  * limitations under the License.
  */
 
-package android.security;
+package android.security.keystore;
 
-/* @hide */
-parcelable KeystoreArguments cpp_header "keystore/KeystoreArguments.h";
+import android.security.keystore.KeystoreResponse;
+import android.security.keymaster.KeyCharacteristics;
+
+/**
+ * @hide
+ */
+oneway interface IKeystoreKeyCharacteristicsCallback {
+	void onFinished(in KeystoreResponse response, in KeyCharacteristics charactersistics);
+}
\ No newline at end of file
diff --git a/keystore/binder/android/security/KeystoreArguments.aidl b/keystore/binder/android/security/keystore/IKeystoreOperationResultCallback.aidl
similarity index 64%
copy from keystore/binder/android/security/KeystoreArguments.aidl
copy to keystore/binder/android/security/keystore/IKeystoreOperationResultCallback.aidl
index dc8ed50..0a51511 100644
--- a/keystore/binder/android/security/KeystoreArguments.aidl
+++ b/keystore/binder/android/security/keystore/IKeystoreOperationResultCallback.aidl
@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2015, The Android Open Source Project
+ * Copyright (c) 2018, 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.
@@ -14,7 +14,14 @@
  * limitations under the License.
  */
 
-package android.security;
+package android.security.keystore;
 
-/* @hide */
-parcelable KeystoreArguments cpp_header "keystore/KeystoreArguments.h";
+import android.security.keystore.KeystoreResponse;
+import android.security.keymaster.OperationResult;
+
+/**
+ * @hide
+ */
+oneway interface IKeystoreOperationResultCallback {
+    void onFinished(in OperationResult result);
+}
\ No newline at end of file
diff --git a/keystore/binder/android/security/KeystoreArguments.aidl b/keystore/binder/android/security/keystore/IKeystoreResponseCallback.aidl
similarity index 68%
copy from keystore/binder/android/security/KeystoreArguments.aidl
copy to keystore/binder/android/security/keystore/IKeystoreResponseCallback.aidl
index dc8ed50..912e605 100644
--- a/keystore/binder/android/security/KeystoreArguments.aidl
+++ b/keystore/binder/android/security/keystore/IKeystoreResponseCallback.aidl
@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2015, The Android Open Source Project
+ * Copyright (c) 2018, 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.
@@ -14,7 +14,13 @@
  * limitations under the License.
  */
 
-package android.security;
+package android.security.keystore;
 
-/* @hide */
-parcelable KeystoreArguments cpp_header "keystore/KeystoreArguments.h";
+import android.security.keystore.KeystoreResponse;
+
+/**
+ * @hide
+ */
+oneway interface IKeystoreResponseCallback {
+    void onFinished(in KeystoreResponse response);
+}
\ No newline at end of file
diff --git a/keystore/binder/android/security/keystore/IKeystoreService.aidl b/keystore/binder/android/security/keystore/IKeystoreService.aidl
new file mode 100644
index 0000000..a760138
--- /dev/null
+++ b/keystore/binder/android/security/keystore/IKeystoreService.aidl
@@ -0,0 +1,78 @@
+/**
+ * Copyright (c) 2018, 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.
+ */
+
+package android.security.keystore;
+
+import android.security.keymaster.KeymasterArguments;
+import android.security.keymaster.KeymasterBlob;
+import android.security.keymaster.OperationResult;
+import android.security.keystore.IKeystoreResponseCallback;
+import android.security.keystore.IKeystoreKeyCharacteristicsCallback;
+import android.security.keystore.IKeystoreExportKeyCallback;
+import android.security.keystore.IKeystoreOperationResultCallback;
+import android.security.keystore.IKeystoreCertificateChainCallback;
+
+/**
+ * @hide
+ */
+interface IKeystoreService {
+    int getState(int userId);
+    byte[] get(String name, int uid);
+    int insert(String name, in byte[] item, int uid, int flags);
+    int del(String name, int uid);
+    int exist(String name, int uid);
+    String[] list(String namePrefix, int uid);
+    int reset();
+    int onUserPasswordChanged(int userId, String newPassword);
+    int lock(int userId);
+    int unlock(int userId, String userPassword);
+    int isEmpty(int userId);
+    String grant(String name, int granteeUid);
+    int ungrant(String name, int granteeUid);
+    long getmtime(String name, int uid);
+    int is_hardware_backed(String string);
+    int clear_uid(long uid);
+
+    int addRngEntropy(IKeystoreResponseCallback cb, in byte[] data, int flags);
+    int generateKey(IKeystoreKeyCharacteristicsCallback cb, String alias, in KeymasterArguments arguments, in byte[] entropy, int uid,
+        int flags);
+    int getKeyCharacteristics (IKeystoreKeyCharacteristicsCallback cb, String alias, in KeymasterBlob clientId, in KeymasterBlob appData,
+        int uid);
+    int importKey(IKeystoreKeyCharacteristicsCallback cb, String alias, in KeymasterArguments arguments, int format,
+        in byte[] keyData, int uid, int flags);
+    int exportKey(IKeystoreExportKeyCallback cb, String alias, int format, in KeymasterBlob clientId,
+        in KeymasterBlob appData, int uid);
+    int begin(in IKeystoreOperationResultCallback cb, IBinder appToken, String alias, int purpose, boolean pruneable,
+        in KeymasterArguments params, in byte[] entropy, int uid);
+    int update(in IKeystoreOperationResultCallback cb, IBinder token, in KeymasterArguments params, in byte[] input);
+    int finish(in IKeystoreOperationResultCallback cb, IBinder token, in KeymasterArguments params, in byte[] signature,
+        in byte[] entropy);
+    int abort(in IKeystoreResponseCallback cb, IBinder token);
+    int addAuthToken(in byte[] authToken);
+    int onUserAdded(int userId, int parentId);
+    int onUserRemoved(int userId);
+    int attestKey(in IKeystoreCertificateChainCallback cb, String alias, in KeymasterArguments params);
+    int attestDeviceIds(in IKeystoreCertificateChainCallback cb, in KeymasterArguments params);
+    int onDeviceOffBody();
+    int importWrappedKey(in IKeystoreKeyCharacteristicsCallback cb, String wrappedKeyAlias, in byte[] wrappedKey,
+        in String wrappingKeyAlias, in byte[] maskingKey, in KeymasterArguments arguments,
+        in long rootSid, in long fingerprintSid);
+    int presentConfirmationPrompt(IBinder listener, String promptText, in byte[] extraData,
+        in String locale, in int uiOptionsAsFlags);
+    int cancelConfirmationPrompt(IBinder listener);
+    boolean isConfirmationPromptSupported();
+    int onKeyguardVisibilityChanged(in boolean isShowing, in int userId);
+}
diff --git a/keystore/binder/android/security/KeystoreArguments.aidl b/keystore/binder/android/security/keystore/KeystoreResponse.aidl
similarity index 70%
rename from keystore/binder/android/security/KeystoreArguments.aidl
rename to keystore/binder/android/security/keystore/KeystoreResponse.aidl
index dc8ed50..128b456 100644
--- a/keystore/binder/android/security/KeystoreArguments.aidl
+++ b/keystore/binder/android/security/keystore/KeystoreResponse.aidl
@@ -1,11 +1,11 @@
-/**
- * Copyright (c) 2015, The Android Open Source Project
+/*
+ * Copyright (C) 2018 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
+ *      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,
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package android.security;
+package android.security.keystore;
 
 /* @hide */
-parcelable KeystoreArguments cpp_header "keystore/KeystoreArguments.h";
+parcelable KeystoreResponse cpp_header "keystore/KeystoreResponse.h";
diff --git a/keystore/include/keystore/KeyCharacteristics.h b/keystore/include/keystore/KeyCharacteristics.h
index 33c5c3a..40d495c 100644
--- a/keystore/include/keystore/KeyCharacteristics.h
+++ b/keystore/include/keystore/KeyCharacteristics.h
@@ -27,11 +27,11 @@
 // Parcelable version of keystore::KeyCharacteristics
 struct KeyCharacteristics : public ::android::Parcelable {
     KeyCharacteristics(){};
-    KeyCharacteristics(keystore::KeyCharacteristics&& other) {
+    KeyCharacteristics(::keystore::KeyCharacteristics&& other) {
         softwareEnforced = std::move(other.softwareEnforced);
         hardwareEnforced = std::move(other.hardwareEnforced);
     }
-    explicit KeyCharacteristics(const keystore::KeyCharacteristics& other) {
+    explicit KeyCharacteristics(const ::keystore::KeyCharacteristics& other) {
         softwareEnforced = KeymasterArguments(other.softwareEnforced);
         hardwareEnforced = KeymasterArguments(other.hardwareEnforced);
     }
diff --git a/keystore/include/keystore/KeymasterArguments.h b/keystore/include/keystore/KeymasterArguments.h
index fb35ee7..b453b11 100644
--- a/keystore/include/keystore/KeymasterArguments.h
+++ b/keystore/include/keystore/KeymasterArguments.h
@@ -26,16 +26,18 @@
 // struct for serializing/deserializing a list of KeyParameters
 struct KeymasterArguments : public Parcelable {
     KeymasterArguments(){};
-    KeymasterArguments(hardware::hidl_vec<keystore::KeyParameter>&& other);
-    explicit KeymasterArguments(const hardware::hidl_vec<keystore::KeyParameter>& other);
+    KeymasterArguments(hardware::hidl_vec<::keystore::KeyParameter>&& other);
+    explicit KeymasterArguments(const hardware::hidl_vec<::keystore::KeyParameter>& other);
 
     status_t readFromParcel(const Parcel* in) override;
     status_t writeToParcel(Parcel* out) const override;
 
-    const inline hardware::hidl_vec<keystore::KeyParameter>& getParameters() const { return data_; }
+    const inline hardware::hidl_vec<::keystore::KeyParameter>& getParameters() const {
+        return data_;
+    }
 
   private:
-    hardware::hidl_vec<keystore::KeyParameter> data_;
+    hardware::hidl_vec<::keystore::KeyParameter> data_;
 };
 
 }  // namespace keymaster
diff --git a/keystore/include/keystore/KeymasterCertificateChain.h b/keystore/include/keystore/KeymasterCertificateChain.h
index 132862c..f251d08 100644
--- a/keystore/include/keystore/KeymasterCertificateChain.h
+++ b/keystore/include/keystore/KeymasterCertificateChain.h
@@ -16,6 +16,7 @@
 #define KEYSTORE_INCLUDE_KEYSTORE_KEYMASTERCERTIFICATECHAIN_H_
 
 #include <binder/Parcelable.h>
+#include <keystore/keymaster_types.h>
 
 namespace android {
 namespace security {
diff --git a/keystore/include/keystore/KeystoreArg.h b/keystore/include/keystore/KeystoreArg.h
deleted file mode 100644
index a5e68f2..0000000
--- a/keystore/include/keystore/KeystoreArg.h
+++ /dev/null
@@ -1,42 +0,0 @@
-/*
- * Copyright (C) 2012 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 KEYSTORE_INCLUDE_KEYSTORE_KEYSTOREARG_H
-#define KEYSTORE_INCLUDE_KEYSTORE_KEYSTOREARG_H
-
-#include <utils/RefBase.h>
-
-namespace android {
-namespace security {
-
-// Simple pair of generic pointer and length of corresponding data structure.
-class KeystoreArg : public RefBase {
-  public:
-    KeystoreArg(const void* data, size_t len) : mData(data), mSize(len) {}
-    ~KeystoreArg() {}
-
-    const void* data() const { return mData; }
-    size_t size() const { return mSize; }
-
-  private:
-    const void* mData;  // provider of the data must handle memory clean-up.
-    size_t mSize;
-};
-
-}  // namespace security
-}  // namespace android
-
-#endif  // KEYSTORE_INCLUDE_KEYSTORE_KEYSTOREARG_H
diff --git a/keystore/include/keystore/KeystoreArguments.h b/keystore/include/keystore/KeystoreArguments.h
deleted file mode 100644
index c0a8b0a..0000000
--- a/keystore/include/keystore/KeystoreArguments.h
+++ /dev/null
@@ -1,42 +0,0 @@
-// Copyright 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.
-
-#ifndef KEYSTORE_INCLUDE_KEYSTORE_KEYSTOREARGUMENTS_H_
-#define KEYSTORE_INCLUDE_KEYSTORE_KEYSTOREARGUMENTS_H_
-
-#include <binder/Parcelable.h>
-#include <utils/RefBase.h>
-#include <utils/Vector.h>
-
-#include "KeystoreArg.h"
-#include "keystore_return_types.h"
-
-namespace android {
-namespace security {
-
-// Parcelable KeystoreArguments.java which simply holds byte[][].
-struct KeystoreArguments : public ::android::Parcelable, public RefBase {
-    status_t readFromParcel(const Parcel* in) override;
-    status_t writeToParcel(Parcel* out) const override;
-
-    const Vector<sp<KeystoreArg>>& getArguments() const { return args; }
-
-  private:
-    Vector<sp<KeystoreArg>> args;
-};
-
-}  // namespace security
-}  // namespace android
-
-#endif  // KEYSTORE_INCLUDE_KEYSTORE_KEYSTOREARGUMENTS_H_
diff --git a/keystore/include/keystore/KeystoreResponse.h b/keystore/include/keystore/KeystoreResponse.h
new file mode 100644
index 0000000..f892585
--- /dev/null
+++ b/keystore/include/keystore/KeystoreResponse.h
@@ -0,0 +1,62 @@
+// Copyright 2018 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 KEYSTORE_INCLUDE_KEYSTORE_RESPONSE_H_
+#define KEYSTORE_INCLUDE_KEYSTORE_RESPONSE_H_
+
+#include <binder/Parcel.h>
+#include <binder/Parcelable.h>
+#include <utils/String8.h>
+
+#include "keystore_return_types.h"
+
+namespace android {
+namespace security {
+namespace keystore {
+
+// struct for holding response code and optionally an error message for keystore
+// AIDL callbacks
+struct KeystoreResponse : public ::android::Parcelable {
+  public:
+    KeystoreResponse() = default;
+    explicit KeystoreResponse(const int response_code, const String16& error_msg)
+        : response_code_(response_code), error_msg_(std::make_unique<String16>(error_msg)) {}
+    explicit KeystoreResponse(const int response_code)
+        : response_code_(response_code), error_msg_() {}
+    KeystoreResponse(const ::keystore::KeyStoreServiceReturnCode& rc)
+        : response_code_(int32_t(rc)), error_msg_() {}
+    KeystoreResponse(const KeystoreResponse& other)
+        : response_code_(other.response_code_), error_msg_() {
+        if (other.error_msg_) {
+            error_msg_ = std::make_unique<String16>(*other.error_msg_);
+        }
+    }
+    KeystoreResponse(KeystoreResponse&& other) = default;
+
+    status_t readFromParcel(const Parcel* in) override;
+    status_t writeToParcel(Parcel* out) const override;
+
+    int response_code() const { return response_code_; }
+    const String16* error_msg() const { return error_msg_.get(); }
+
+  private:
+    int response_code_;
+    std::unique_ptr<String16> error_msg_;
+};
+
+}  // namespace keystore
+}  // namespace security
+}  // namespace android
+
+#endif  // KEYSTORE_INCLUDE_KEYSTORE_RESPONSE_H_
diff --git a/keystore/include/keystore/keystore_client_impl.h b/keystore/include/keystore/keystore_client_impl.h
index 9edd082..0bcef98 100644
--- a/keystore/include/keystore/keystore_client_impl.h
+++ b/keystore/include/keystore/keystore_client_impl.h
@@ -17,11 +17,12 @@
 
 #include "keystore_client.h"
 
+#include <future>
 #include <map>
 #include <string>
 #include <vector>
 
-#include <android/security/IKeystoreService.h>
+#include <android/security/keystore/IKeystoreService.h>
 #include <binder/IBinder.h>
 #include <binder/IServiceManager.h>
 #include <utils/StrongPointer.h>
@@ -109,7 +110,7 @@
 
     android::sp<android::IServiceManager> service_manager_;
     android::sp<android::IBinder> keystore_binder_;
-    android::sp<android::security::IKeystoreService> keystore_;
+    android::sp<android::security::keystore::IKeystoreService> keystore_;
     uint64_t next_virtual_handle_ = 1;
     std::map<uint64_t, android::sp<android::IBinder>> active_operations_;
 
diff --git a/keystore/include/keystore/keystore_promises.h b/keystore/include/keystore/keystore_promises.h
new file mode 100644
index 0000000..3d45016
--- /dev/null
+++ b/keystore/include/keystore/keystore_promises.h
@@ -0,0 +1,72 @@
+/*
+**
+** Copyright 2018, 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 KEYSTORE_INCLUDE_KEYSTORE_KEYSTORE_PROMISES_H_
+#define KEYSTORE_INCLUDE_KEYSTORE_KEYSTORE_PROMISES_H_
+
+#include <android/security/keystore/BnKeystoreCertificateChainCallback.h>
+#include <android/security/keystore/BnKeystoreExportKeyCallback.h>
+#include <android/security/keystore/BnKeystoreKeyCharacteristicsCallback.h>
+#include <android/security/keystore/BnKeystoreOperationResultCallback.h>
+#include <android/security/keystore/BnKeystoreResponseCallback.h>
+#include <future>
+
+namespace keystore {
+
+template <typename BnInterface, typename Result>
+class CallbackPromise : public BnInterface, public std::promise<Result> {
+  public:
+    ::android::binder::Status onFinished(const Result& result) override {
+        this->set_value(result);
+        return ::android::binder::Status::ok();
+    }
+};
+
+template <typename BnInterface, typename... Results>
+class CallbackPromise<BnInterface, std::tuple<Results...>>
+    : public BnInterface, public std::promise<std::tuple<Results...>> {
+  public:
+    ::android::binder::Status onFinished(const Results&... results) override {
+        this->set_value({results...});
+        return ::android::binder::Status::ok();
+    }
+};
+
+using OperationResultPromise =
+    CallbackPromise<::android::security::keystore::BnKeystoreOperationResultCallback,
+                    ::android::security::keymaster::OperationResult>;
+
+using KeystoreResponsePromise =
+    CallbackPromise<::android::security::keystore::BnKeystoreResponseCallback,
+                    ::android::security::keystore::KeystoreResponse>;
+
+using KeyCharacteristicsPromise =
+    CallbackPromise<::android::security::keystore::BnKeystoreKeyCharacteristicsCallback,
+                    std::tuple<::android::security::keystore::KeystoreResponse,
+                               ::android::security::keymaster::KeyCharacteristics>>;
+using KeystoreExportPromise =
+    CallbackPromise<::android::security::keystore::BnKeystoreExportKeyCallback,
+                    ::android::security::keymaster::ExportResult>;
+
+using KeyCertChainPromise =
+    CallbackPromise<::android::security::keystore::BnKeystoreCertificateChainCallback,
+                    std::tuple<::android::security::keystore::KeystoreResponse,
+                               ::android::security::keymaster::KeymasterCertificateChain>>;
+
+}  // namespace keystore
+
+#endif  // KEYSTORE_INCLUDE_KEYSTORE_KEYSTORE_PROMISES_H_
diff --git a/keystore/key_store_service.cpp b/keystore/key_store_service.cpp
index 7ce58ca..2f07fbf 100644
--- a/keystore/key_store_service.cpp
+++ b/keystore/key_store_service.cpp
@@ -17,7 +17,6 @@
 #define LOG_TAG "keystore"
 
 #include "key_store_service.h"
-#include "include/keystore/KeystoreArg.h"
 
 #include <fcntl.h>
 #include <sys/stat.h>
@@ -57,7 +56,6 @@
 namespace {
 
 using ::android::binder::Status;
-using android::security::KeystoreArg;
 using android::security::keymaster::ExportResult;
 using android::security::keymaster::KeymasterArguments;
 using android::security::keymaster::KeymasterBlob;
@@ -65,6 +63,9 @@
 using android::security::keymaster::operationFailed;
 using android::security::keymaster::OperationResult;
 using ConfirmationResponseCode = android::hardware::confirmationui::V1_0::ResponseCode;
+using ::android::security::keystore::IKeystoreOperationResultCallback;
+using ::android::security::keystore::IKeystoreResponseCallback;
+using ::android::security::keystore::KeystoreResponse;
 
 constexpr double kIdRotationPeriod = 30 * 24 * 60 * 60; /* Thirty days, in seconds */
 const char* kTimestampFilePath = "timestamp";
@@ -82,6 +83,9 @@
                         [&](const KeyParameter& param) { return param.tag == tag; });
 }
 
+#define AIDL_RETURN(rc)                                                                            \
+    (*_aidl_return = static_cast<int32_t>(KeyStoreServiceReturnCode(rc)), Status::ok())
+
 std::pair<KeyStoreServiceReturnCode, bool> hadFactoryResetSinceIdRotation() {
     struct stat sbuf;
     if (stat(kTimestampFilePath, &sbuf) == 0) {
@@ -545,113 +549,93 @@
     return Status::ok();
 }
 
-Status KeyStoreService::addRngEntropy(const ::std::vector<uint8_t>& entropy, int32_t flags,
-                                      int32_t* aidl_return) {
+Status KeyStoreService::addRngEntropy(
+    const ::android::sp<::android::security::keystore::IKeystoreResponseCallback>& cb,
+    const ::std::vector<uint8_t>& entropy, int32_t flags, int32_t* _aidl_return) {
     auto device = mKeyStore->getDevice(flagsToSecurityLevel(flags));
     if (!device) {
-        *aidl_return = static_cast<int32_t>(ErrorCode::HARDWARE_TYPE_UNAVAILABLE);
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::HARDWARE_TYPE_UNAVAILABLE);
     }
-    std::promise<KeyStoreServiceReturnCode> resultPromise;
-    auto resultFuture = resultPromise.get_future();
 
-    device->addRngEntropy(
-        entropy, [&](Return<ErrorCode> rc) { resultPromise.set_value(KS_HANDLE_HIDL_ERROR(rc)); });
-    resultFuture.wait();
-    *aidl_return = int32_t(resultFuture.get());
-    return Status::ok();
+    device->addRngEntropy(entropy, [cb](Return<ErrorCode> rc) {
+        cb->onFinished(KeyStoreServiceReturnCode(KS_HANDLE_HIDL_ERROR(rc)));
+    });
+
+    return AIDL_RETURN(ResponseCode::NO_ERROR);
 }
 
-Status
-KeyStoreService::generateKey(const String16& name, const KeymasterArguments& params,
-                             const ::std::vector<uint8_t>& entropy, int uid, int flags,
-                             android::security::keymaster::KeyCharacteristics* outCharacteristics,
-                             int32_t* aidl_return) {
+Status KeyStoreService::generateKey(
+    const ::android::sp<::android::security::keystore::IKeystoreKeyCharacteristicsCallback>& cb,
+    const String16& name, const KeymasterArguments& params, const ::std::vector<uint8_t>& entropy,
+    int uid, int flags, int32_t* _aidl_return) {
     // TODO(jbires): remove this getCallingUid call upon implementation of b/25646100
     uid_t originalUid = IPCThreadState::self()->getCallingUid();
     uid = getEffectiveUid(uid);
     auto logOnScopeExit = android::base::make_scope_guard([&] {
         if (__android_log_security()) {
             android_log_event_list(SEC_TAG_AUTH_KEY_GENERATED)
-                << int32_t(*aidl_return == static_cast<int32_t>(ResponseCode::NO_ERROR))
+                << int32_t(*_aidl_return == static_cast<int32_t>(ResponseCode::NO_ERROR))
                 << String8(name) << int32_t(uid) << LOG_ID_SECURITY;
         }
     });
     KeyStoreServiceReturnCode rc =
         checkBinderPermissionAndKeystoreState(P_INSERT, uid, flags & KEYSTORE_FLAG_ENCRYPTED);
     if (!rc.isOk()) {
-        *aidl_return = static_cast<int32_t>(rc);
-        return Status::ok();
+        return AIDL_RETURN(rc);
     }
     if ((flags & KEYSTORE_FLAG_CRITICAL_TO_DEVICE_ENCRYPTION) && get_app_id(uid) != AID_SYSTEM) {
         ALOGE("Non-system uid %d cannot set FLAG_CRITICAL_TO_DEVICE_ENCRYPTION", uid);
-        *aidl_return = static_cast<int32_t>(ResponseCode::PERMISSION_DENIED);
-        return Status::ok();
+        return AIDL_RETURN(ResponseCode::PERMISSION_DENIED);
     }
 
     if (containsTag(params.getParameters(), Tag::INCLUDE_UNIQUE_ID)) {
         // TODO(jbires): remove uid checking upon implementation of b/25646100
         if (!checkBinderPermission(P_GEN_UNIQUE_ID) ||
             originalUid != IPCThreadState::self()->getCallingUid()) {
-            *aidl_return = static_cast<int32_t>(ResponseCode::PERMISSION_DENIED);
-            return Status::ok();
+            return AIDL_RETURN(ResponseCode::PERMISSION_DENIED);
         }
     }
 
     SecurityLevel securityLevel = flagsToSecurityLevel(flags);
     auto dev = mKeyStore->getDevice(securityLevel);
     if (!dev) {
-        *aidl_return = static_cast<int32_t>(ErrorCode::HARDWARE_TYPE_UNAVAILABLE);
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::HARDWARE_TYPE_UNAVAILABLE);
     }
 
     String8 name8(name);
     auto lockedEntry = mKeyStore->getLockedBlobEntryIfNotExists(name8.string(), uid);
     if (!lockedEntry) {
-        *aidl_return = static_cast<int32_t>(ResponseCode::KEY_ALREADY_EXISTS);
-        return Status::ok();
+        return AIDL_RETURN(ResponseCode::KEY_ALREADY_EXISTS);
     }
 
     logOnScopeExit.Disable();
 
-    std::promise<KeyStoreServiceReturnCode> resultPromise;
-    auto resultFuture = resultPromise.get_future();
+    dev->generateKey(
+        std::move(lockedEntry), params.getParameters(), entropy, flags,
+        [cb, uid, name](KeyStoreServiceReturnCode rc, KeyCharacteristics keyCharacteristics) {
+            if (__android_log_security()) {
+                android_log_event_list(SEC_TAG_AUTH_KEY_GENERATED)
+                    << rc.isOk() << String8(name) << int32_t(uid) << LOG_ID_SECURITY;
+            }
+            cb->onFinished(rc,
+                           android::security::keymaster::KeyCharacteristics(keyCharacteristics));
+        });
 
-    dev->generateKey(std::move(lockedEntry), params.getParameters(), entropy, flags,
-                     [&, uid](KeyStoreServiceReturnCode rc, KeyCharacteristics keyCharacteristics) {
-                         if (outCharacteristics && rc.isOk()) {
-                             *outCharacteristics = android::security::keymaster::KeyCharacteristics(
-                                 keyCharacteristics);
-                         }
-                         if (__android_log_security()) {
-                             android_log_event_list(SEC_TAG_AUTH_KEY_GENERATED)
-                                 << rc.isOk() << String8(name) << int32_t(uid) << LOG_ID_SECURITY;
-                         }
-                         resultPromise.set_value(rc);
-                     });
-
-    resultFuture.wait();
-    *aidl_return = int32_t(resultFuture.get());
-    return Status::ok();
+    return AIDL_RETURN(ResponseCode::NO_ERROR);
 }
 
 Status KeyStoreService::getKeyCharacteristics(
+    const ::android::sp<::android::security::keystore::IKeystoreKeyCharacteristicsCallback>& cb,
     const String16& name, const ::android::security::keymaster::KeymasterBlob& clientId,
     const ::android::security::keymaster::KeymasterBlob& appData, int32_t uid,
-    ::android::security::keymaster::KeyCharacteristics* outCharacteristics, int32_t* aidl_return) {
-    if (!outCharacteristics) {
-        *aidl_return =
-            static_cast<int32_t>(KeyStoreServiceReturnCode(ErrorCode::UNEXPECTED_NULL_POINTER));
-        return Status::ok();
-    }
+    int32_t* _aidl_return) {
 
     uid_t targetUid = getEffectiveUid(uid);
     uid_t callingUid = IPCThreadState::self()->getCallingUid();
     if (!is_granted_to(callingUid, targetUid)) {
         ALOGW("uid %d not permitted to act for uid %d in getKeyCharacteristics", callingUid,
               targetUid);
-        *aidl_return = static_cast<int32_t>(ResponseCode::PERMISSION_DENIED);
-        return Status::ok();
+        return AIDL_RETURN(ResponseCode::PERMISSION_DENIED);
     }
 
     String8 name8(name);
@@ -665,47 +649,37 @@
         mKeyStore->getKeyForName(name8, targetUid, TYPE_KEYMASTER_10);
 
     if (rc != ResponseCode::NO_ERROR) {
-        *aidl_return = static_cast<int32_t>(rc);
-        return Status::ok();
+        return AIDL_RETURN(rc);
     }
 
     auto dev = mKeyStore->getDevice(keyBlob);
     if (!dev) {
-        *aidl_return = static_cast<int32_t>(ResponseCode::SYSTEM_ERROR);
-        return Status::ok();
+        return AIDL_RETURN(ResponseCode::SYSTEM_ERROR);
     }
 
     // If the charBlob is up to date, it simply moves the argument blobs to the returned blobs
     // and extracts the characteristics on the way. Otherwise it updates the cache file with data
     // from keymaster. It may also upgrade the key blob.
-    std::promise<KeyStoreServiceReturnCode> resultPromise;
-    auto resultFuture = resultPromise.get_future();
-
     dev->getKeyCharacteristics(
         std::move(lockedEntry), clientId.getData(), appData.getData(), std::move(keyBlob),
         std::move(charBlob),
-        [&](KeyStoreServiceReturnCode rc, KeyCharacteristics keyCharacteristics) {
-            if (outCharacteristics && rc.isOk()) {
-                *outCharacteristics = std::move(keyCharacteristics);
-            }
-            resultPromise.set_value(rc);
+        [cb](KeyStoreServiceReturnCode rc, KeyCharacteristics keyCharacteristics) {
+            cb->onFinished(rc,
+                           android::security::keymaster::KeyCharacteristics(keyCharacteristics));
         });
 
-    resultFuture.wait();
-    *aidl_return = int32_t(resultFuture.get());
-    return Status::ok();
+    return AIDL_RETURN(ResponseCode::NO_ERROR);
 }
 
-Status
-KeyStoreService::importKey(const String16& name, const KeymasterArguments& params, int32_t format,
-                           const ::std::vector<uint8_t>& keyData, int uid, int flags,
-                           ::android::security::keymaster::KeyCharacteristics* outCharacteristics,
-                           int32_t* aidl_return) {
+Status KeyStoreService::importKey(
+    const ::android::sp<::android::security::keystore::IKeystoreKeyCharacteristicsCallback>& cb,
+    const String16& name, const KeymasterArguments& params, int32_t format,
+    const ::std::vector<uint8_t>& keyData, int uid, int flags, int32_t* _aidl_return) {
     uid = getEffectiveUid(uid);
     auto logOnScopeExit = android::base::make_scope_guard([&] {
         if (__android_log_security()) {
             android_log_event_list(SEC_TAG_KEY_IMPORTED)
-                << int32_t(*aidl_return == static_cast<int32_t>(ResponseCode::NO_ERROR))
+                << int32_t(*_aidl_return == static_cast<int32_t>(ResponseCode::NO_ERROR))
                 << String8(name) << int32_t(uid) << LOG_ID_SECURITY;
         }
     });
@@ -713,21 +687,18 @@
         checkBinderPermissionAndKeystoreState(P_INSERT, uid, flags & KEYSTORE_FLAG_ENCRYPTED);
     if (!rc.isOk()) {
         LOG(ERROR) << "permissission denied";
-        *aidl_return = static_cast<int32_t>(rc);
-        return Status::ok();
+        return AIDL_RETURN(rc);
     }
     if ((flags & KEYSTORE_FLAG_CRITICAL_TO_DEVICE_ENCRYPTION) && get_app_id(uid) != AID_SYSTEM) {
         ALOGE("Non-system uid %d cannot set FLAG_CRITICAL_TO_DEVICE_ENCRYPTION", uid);
-        *aidl_return = static_cast<int32_t>(ResponseCode::PERMISSION_DENIED);
-        return Status::ok();
+        return AIDL_RETURN(ResponseCode::PERMISSION_DENIED);
     }
 
     SecurityLevel securityLevel = flagsToSecurityLevel(flags);
     auto dev = mKeyStore->getDevice(securityLevel);
     if (!dev) {
         LOG(ERROR) << "importKey - cound not get keymaster device";
-        *aidl_return = static_cast<int32_t>(ErrorCode::HARDWARE_TYPE_UNAVAILABLE);
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::HARDWARE_TYPE_UNAVAILABLE);
     }
 
     String8 name8(name);
@@ -735,44 +706,37 @@
     if (!lockedEntry) {
         LOG(ERROR) << "importKey - key: " << name8.string() << " " << int(uid)
                    << " already exists.";
-        *aidl_return = static_cast<int32_t>(ResponseCode::KEY_ALREADY_EXISTS);
-        return Status::ok();
+        return AIDL_RETURN(ResponseCode::KEY_ALREADY_EXISTS);
     }
 
     logOnScopeExit.Disable();
 
-    std::promise<KeyStoreServiceReturnCode> resultPromise;
-    auto resultFuture = resultPromise.get_future();
+    dev->importKey(
+        std::move(lockedEntry), params.getParameters(), KeyFormat(format), keyData, flags,
+        [cb, uid, name](KeyStoreServiceReturnCode rc, KeyCharacteristics keyCharacteristics) {
+            if (__android_log_security()) {
+                android_log_event_list(SEC_TAG_KEY_IMPORTED)
+                    << rc.isOk() << String8(name) << int32_t(uid) << LOG_ID_SECURITY;
+            }
+            cb->onFinished(rc,
+                           android::security::keymaster::KeyCharacteristics(keyCharacteristics));
+        });
 
-    dev->importKey(std::move(lockedEntry), params.getParameters(), KeyFormat(format), keyData,
-                   flags,
-                   [&, uid](KeyStoreServiceReturnCode rc, KeyCharacteristics keyCharacteristics) {
-                       if (outCharacteristics && rc.isOk()) {
-                           *outCharacteristics = std::move(keyCharacteristics);
-                       }
-                       if (__android_log_security()) {
-                           android_log_event_list(SEC_TAG_KEY_IMPORTED)
-                               << rc.isOk() << String8(name) << int32_t(uid) << LOG_ID_SECURITY;
-                       }
-                       resultPromise.set_value(rc);
-                   });
-
-    resultFuture.wait();
-    *aidl_return = int32_t(resultFuture.get());
-    return Status::ok();
+    return AIDL_RETURN(ResponseCode::NO_ERROR);
 }
 
-Status KeyStoreService::exportKey(const String16& name, int32_t format,
-                                  const ::android::security::keymaster::KeymasterBlob& clientId,
-                                  const ::android::security::keymaster::KeymasterBlob& appData,
-                                  int32_t uid, ExportResult* result) {
+Status KeyStoreService::exportKey(
+    const ::android::sp<::android::security::keystore::IKeystoreExportKeyCallback>& cb,
+    const String16& name, int32_t format,
+    const ::android::security::keymaster::KeymasterBlob& clientId,
+    const ::android::security::keymaster::KeymasterBlob& appData, int32_t uid,
+    int32_t* _aidl_return) {
 
     uid_t targetUid = getEffectiveUid(uid);
     uid_t callingUid = IPCThreadState::self()->getCallingUid();
     if (!is_granted_to(callingUid, targetUid)) {
         ALOGW("uid %d not permitted to act for uid %d in exportKey", callingUid, targetUid);
-        result->resultCode = ResponseCode::PERMISSION_DENIED;
-        return Status::ok();
+        return AIDL_RETURN(ResponseCode::PERMISSION_DENIED);
     }
 
     String8 name8(name);
@@ -785,43 +749,35 @@
     std::tie(rc, keyBlob, charBlob, lockedEntry) =
         mKeyStore->getKeyForName(name8, targetUid, TYPE_KEYMASTER_10);
     if (!rc) {
-        result->resultCode = rc;
-        return Status::ok();
+        return AIDL_RETURN(rc);
     }
 
     auto dev = mKeyStore->getDevice(keyBlob);
-    std::promise<void> resultPromise;
-    auto resultFuture = resultPromise.get_future();
 
     dev->exportKey(std::move(lockedEntry), KeyFormat(format), clientId.getData(), appData.getData(),
-                   std::move(keyBlob), std::move(charBlob), [&](ExportResult exportResult) {
-                       *result = std::move(exportResult);
-                       resultPromise.set_value();
-                   });
+                   std::move(keyBlob), std::move(charBlob),
+                   [cb](ExportResult exportResult) { cb->onFinished(exportResult); });
 
-    resultFuture.wait();
-    return Status::ok();
+    return AIDL_RETURN(ResponseCode::NO_ERROR);
 }
 
-Status KeyStoreService::begin(const sp<IBinder>& appToken, const String16& name, int32_t purpose,
+Status KeyStoreService::begin(const sp<IKeystoreOperationResultCallback>& cb,
+                              const sp<IBinder>& appToken, const String16& name, int32_t purpose,
                               bool pruneable, const KeymasterArguments& params,
                               const ::std::vector<uint8_t>& entropy, int32_t uid,
-                              OperationResult* result) {
+                              int32_t* _aidl_return) {
     uid_t callingUid = IPCThreadState::self()->getCallingUid();
     uid_t targetUid = getEffectiveUid(uid);
     if (!is_granted_to(callingUid, targetUid)) {
         ALOGW("uid %d not permitted to act for uid %d in begin", callingUid, targetUid);
-        result->resultCode = ResponseCode::PERMISSION_DENIED;
-        return Status::ok();
+        return AIDL_RETURN(ResponseCode::PERMISSION_DENIED);
     }
     if (!pruneable && get_app_id(callingUid) != AID_SYSTEM) {
         ALOGE("Non-system uid %d trying to start non-pruneable operation", callingUid);
-        result->resultCode = ResponseCode::PERMISSION_DENIED;
-        return Status::ok();
+        return AIDL_RETURN(ResponseCode::PERMISSION_DENIED);
     }
     if (!checkAllowedOperationParams(params.getParameters())) {
-        result->resultCode = ErrorCode::INVALID_ARGUMENT;
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::INVALID_ARGUMENT);
     }
 
     String8 name8(name);
@@ -834,104 +790,85 @@
         mKeyStore->getKeyForName(name8, targetUid, TYPE_KEYMASTER_10);
 
     if (rc == ResponseCode::LOCKED && keyBlob.isSuperEncrypted()) {
-        return result->resultCode = ErrorCode::KEY_USER_NOT_AUTHENTICATED, Status::ok();
+        return AIDL_RETURN(ErrorCode::KEY_USER_NOT_AUTHENTICATED);
     }
-    if (rc != ResponseCode::NO_ERROR) return result->resultCode = rc, Status::ok();
+    if (rc != ResponseCode::NO_ERROR) return AIDL_RETURN(rc);
 
     auto dev = mKeyStore->getDevice(keyBlob);
     AuthorizationSet opParams = params.getParameters();
-    KeyCharacteristics characteristics;
-
-    std::promise<void> resultPromise;
-    auto resultFuture = resultPromise.get_future();
 
     dev->begin(std::move(lockedEntry), appToken, std::move(keyBlob), std::move(charBlob), pruneable,
                static_cast<KeyPurpose>(purpose), std::move(opParams), entropy,
-               [&, this](OperationResult result_) {
+               [this, cb, dev](OperationResult result_) {
                    if (result_.resultCode.isOk() ||
                        result_.resultCode == ResponseCode::OP_AUTH_NEEDED) {
                        addOperationDevice(result_.token, dev);
                    }
-                   if (result) *result = std::move(result_);
-                   resultPromise.set_value();
+                   cb->onFinished(result_);
                });
 
-    resultFuture.wait();
-    return Status::ok();
+    return AIDL_RETURN(ResponseCode::NO_ERROR);
 }
 
-Status KeyStoreService::update(const sp<IBinder>& token, const KeymasterArguments& params,
-                               const ::std::vector<uint8_t>& data, OperationResult* result) {
+Status KeyStoreService::update(const ::android::sp<IKeystoreOperationResultCallback>& cb,
+                               const ::android::sp<::android::IBinder>& token,
+                               const ::android::security::keymaster::KeymasterArguments& params,
+                               const ::std::vector<uint8_t>& input, int32_t* _aidl_return) {
     if (!checkAllowedOperationParams(params.getParameters())) {
-        result->resultCode = ErrorCode::INVALID_ARGUMENT;
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::INVALID_ARGUMENT);
     }
 
-    std::promise<void> resultPromise;
-    auto resultFuture = resultPromise.get_future();
-
     auto dev = getOperationDevice(token);
     if (!dev) {
-        *result = operationFailed(ErrorCode::INVALID_OPERATION_HANDLE);
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::INVALID_OPERATION_HANDLE);
     }
 
-    dev->update(token, params.getParameters(), data, [&](OperationResult result_) {
+    dev->update(token, params.getParameters(), input, [this, cb, token](OperationResult result_) {
         if (!result_.resultCode.isOk()) {
             removeOperationDevice(token);
         }
-        if (result) *result = std::move(result_);
-        resultPromise.set_value();
+        cb->onFinished(result_);
     });
 
-    resultFuture.wait();
-    return Status::ok();
+    return AIDL_RETURN(ResponseCode::NO_ERROR);
 }
 
-Status KeyStoreService::finish(const sp<IBinder>& token, const KeymasterArguments& params,
+Status KeyStoreService::finish(const ::android::sp<IKeystoreOperationResultCallback>& cb,
+                               const ::android::sp<::android::IBinder>& token,
+                               const ::android::security::keymaster::KeymasterArguments& params,
                                const ::std::vector<uint8_t>& signature,
-                               const ::std::vector<uint8_t>& entropy, OperationResult* result) {
+                               const ::std::vector<uint8_t>& entropy, int32_t* _aidl_return) {
     if (!checkAllowedOperationParams(params.getParameters())) {
-        result->resultCode = ErrorCode::INVALID_ARGUMENT;
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::INVALID_ARGUMENT);
     }
 
-    std::promise<void> resultPromise;
-    auto resultFuture = resultPromise.get_future();
-
     auto dev = getOperationDevice(token);
     if (!dev) {
-        *result = operationFailed(ErrorCode::INVALID_OPERATION_HANDLE);
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::INVALID_OPERATION_HANDLE);
     }
 
     dev->finish(token, params.getParameters(), {}, signature, entropy,
-                [&](OperationResult result_) {
+                [this, cb, token](OperationResult result_) {
                     if (!result_.resultCode.isOk()) {
                         removeOperationDevice(token);
                     }
-                    if (result) *result = std::move(result_);
-                    resultPromise.set_value();
+                    cb->onFinished(result_);
                 });
 
-    resultFuture.wait();
-    return Status::ok();
+    return AIDL_RETURN(ResponseCode::NO_ERROR);
 }
 
-Status KeyStoreService::abort(const sp<IBinder>& token, int32_t* aidl_return) {
+Status KeyStoreService::abort(const ::android::sp<IKeystoreResponseCallback>& cb,
+                              const ::android::sp<::android::IBinder>& token,
+                              int32_t* _aidl_return) {
     auto dev = getOperationDevice(token);
     if (!dev) {
-        *aidl_return = static_cast<int32_t>(ErrorCode::INVALID_OPERATION_HANDLE);
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::INVALID_OPERATION_HANDLE);
     }
-    std::promise<KeyStoreServiceReturnCode> resultPromise;
-    auto resultFuture = resultPromise.get_future();
 
-    dev->abort(token, [&](KeyStoreServiceReturnCode rc) { resultPromise.set_value(rc); });
+    dev->abort(token, [cb](KeyStoreServiceReturnCode rc) { cb->onFinished(rc); });
 
-    resultFuture.wait();
-    *aidl_return = int32_t(resultFuture.get());
-    return Status::ok();
+    return AIDL_RETURN(ResponseCode::NO_ERROR);
 }
 
 Status KeyStoreService::addAuthToken(const ::std::vector<uint8_t>& authTokenAsVector,
@@ -987,13 +924,12 @@
     return result;
 }
 
-Status KeyStoreService::attestKey(const String16& name, const KeymasterArguments& params,
-                                  ::android::security::keymaster::KeymasterCertificateChain* chain,
-                                  int32_t* aidl_return) {
+Status KeyStoreService::attestKey(
+    const ::android::sp<::android::security::keystore::IKeystoreCertificateChainCallback>& cb,
+    const String16& name, const KeymasterArguments& params, int32_t* _aidl_return) {
     // check null output if method signature is updated and return ErrorCode::OUTPUT_PARAMETER_NULL
     if (!checkAllowedOperationParams(params.getParameters())) {
-        *aidl_return = static_cast<int32_t>(KeyStoreServiceReturnCode(ErrorCode::INVALID_ARGUMENT));
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::INVALID_ARGUMENT);
     }
 
     uid_t callingUid = IPCThreadState::self()->getCallingUid();
@@ -1007,15 +943,13 @@
     // unique device ID.
     if ((needsIdAttestation && !isSomeUserSystemUid) ||
         (needsUniqueIdAttestation && !isPrimaryUserSystemUid)) {
-        *aidl_return = static_cast<int32_t>(KeyStoreServiceReturnCode(ErrorCode::INVALID_ARGUMENT));
-        return Status::ok();
+        return AIDL_RETURN(KeyStoreServiceReturnCode(ErrorCode::INVALID_ARGUMENT));
     }
 
     AuthorizationSet mutableParams = params.getParameters();
     KeyStoreServiceReturnCode rc = updateParamsForAttestation(callingUid, &mutableParams);
     if (!rc.isOk()) {
-        *aidl_return = static_cast<int32_t>(rc);
-        return Status::ok();
+        return AIDL_RETURN(rc);
     }
 
     String8 name8(name);
@@ -1026,75 +960,67 @@
     std::tie(rc, keyBlob, charBlob, lockedEntry) =
         mKeyStore->getKeyForName(name8, callingUid, TYPE_KEYMASTER_10);
 
-    std::promise<KeyStoreServiceReturnCode> resultPromise;
-    auto resultFuture = resultPromise.get_future();
-
-    auto worker_cb = [&](Return<void> rc,
-                         std::tuple<ErrorCode, hidl_vec<hidl_vec<uint8_t>>>&& hidlResult) {
-        auto& [ret, certChain] = hidlResult;
-        if (!rc.isOk()) {
-            resultPromise.set_value(ResponseCode::SYSTEM_ERROR);
-            return;
-        }
-        if (ret == ErrorCode::OK && chain) {
-            *chain = KeymasterCertificateChain(certChain);
-        }
-        resultPromise.set_value(ret);
-    };
     auto dev = mKeyStore->getDevice(keyBlob);
     auto hidlKey = blob2hidlVec(keyBlob);
-    dev->attestKey(std::move(hidlKey), mutableParams.hidl_data(), worker_cb);
+    dev->attestKey(
+        std::move(hidlKey), mutableParams.hidl_data(),
+        [cb](Return<void> rc, std::tuple<ErrorCode, hidl_vec<hidl_vec<uint8_t>>>&& hidlResult) {
+            auto& [ret, certChain] = hidlResult;
+            if (!rc.isOk()) {
+                cb->onFinished(KeyStoreServiceReturnCode(ResponseCode::SYSTEM_ERROR), {});
+            } else if (ret != ErrorCode::OK) {
+                cb->onFinished(KeyStoreServiceReturnCode(ret), {});
+            } else {
+                cb->onFinished(KeyStoreServiceReturnCode(ret),
+                               KeymasterCertificateChain(std::move(certChain)));
+            }
+        });
 
-    resultFuture.wait();
-    *aidl_return = static_cast<int32_t>(resultFuture.get());
-    return Status::ok();
+    return AIDL_RETURN(ResponseCode::NO_ERROR);
 }
 
-Status
-KeyStoreService::attestDeviceIds(const KeymasterArguments& params,
-                                 ::android::security::keymaster::KeymasterCertificateChain* chain,
-                                 int32_t* aidl_return) {
+// My IDE defines "CAPTURE_MOVE(x) x" because it does not understand generalized lambda captures.
+// It should never be redefined by a build system though.
+#ifndef CAPTURE_MOVE
+#define CAPTURE_MOVE(x) x = std::move(x)
+#endif
+
+Status KeyStoreService::attestDeviceIds(
+    const ::android::sp<::android::security::keystore::IKeystoreCertificateChainCallback>& cb,
+    const KeymasterArguments& params, int32_t* _aidl_return) {
     // check null output if method signature is updated and return ErrorCode::OUTPUT_PARAMETER_NULL
 
     if (!checkAllowedOperationParams(params.getParameters())) {
-        *aidl_return = static_cast<int32_t>(KeyStoreServiceReturnCode(ErrorCode::INVALID_ARGUMENT));
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::INVALID_ARGUMENT);
     }
 
     if (!isDeviceIdAttestationRequested(params)) {
         // There is an attestKey() method for attesting keys without device ID attestation.
-        *aidl_return = static_cast<int32_t>(KeyStoreServiceReturnCode(ErrorCode::INVALID_ARGUMENT));
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::INVALID_ARGUMENT);
     }
 
     uid_t callingUid = IPCThreadState::self()->getCallingUid();
     sp<IBinder> binder = defaultServiceManager()->getService(String16("permission"));
     if (binder == nullptr) {
-        *aidl_return =
-            static_cast<int32_t>(KeyStoreServiceReturnCode(ErrorCode::CANNOT_ATTEST_IDS));
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::CANNOT_ATTEST_IDS);
     }
     if (!interface_cast<IPermissionController>(binder)->checkPermission(
             String16("android.permission.READ_PRIVILEGED_PHONE_STATE"),
             IPCThreadState::self()->getCallingPid(), callingUid)) {
-        *aidl_return =
-            static_cast<int32_t>(KeyStoreServiceReturnCode(ErrorCode::CANNOT_ATTEST_IDS));
-        return Status::ok();
+        return AIDL_RETURN(ErrorCode::CANNOT_ATTEST_IDS);
     }
 
     AuthorizationSet mutableParams = params.getParameters();
     KeyStoreServiceReturnCode rc = updateParamsForAttestation(callingUid, &mutableParams);
     if (!rc.isOk()) {
-        *aidl_return = static_cast<int32_t>(rc);
-        return Status::ok();
+        return AIDL_RETURN(rc);
     }
 
     // Generate temporary key.
     auto dev = mKeyStore->getDevice(SecurityLevel::TRUSTED_ENVIRONMENT);
 
     if (!dev) {
-        *aidl_return = static_cast<int32_t>(ResponseCode::SYSTEM_ERROR);
-        return Status::ok();
+        return AIDL_RETURN(ResponseCode::SYSTEM_ERROR);
     }
 
 
@@ -1110,44 +1036,45 @@
 
     dev->generateKey(
         keyCharacteristics.hidl_data(),
-        [&, dev](Return<void> rc,
-                 std::tuple<ErrorCode, ::std::vector<uint8_t>, KeyCharacteristics>&& hidlResult) {
+        [cb, dev, CAPTURE_MOVE(mutableParams)](
+            Return<void> rc,
+            std::tuple<ErrorCode, ::std::vector<uint8_t>, KeyCharacteristics>&& hidlResult) {
             auto& [ret, hidlKeyBlob_, dummyCharacteristics] = hidlResult;
             auto hidlKeyBlob = std::move(hidlKeyBlob_);
             if (!rc.isOk()) {
-                resultPromise.set_value(ResponseCode::SYSTEM_ERROR);
+                cb->onFinished(KeyStoreServiceReturnCode(ResponseCode::SYSTEM_ERROR), {});
                 return;
             }
             if (ret != ErrorCode::OK) {
-                resultPromise.set_value(ret);
+                cb->onFinished(KeyStoreServiceReturnCode(ret), {});
                 return;
             }
             dev->attestKey(
                 hidlKeyBlob, mutableParams.hidl_data(),
-                [&, dev,
+                [cb, dev,
                  hidlKeyBlob](Return<void> rc,
                               std::tuple<ErrorCode, hidl_vec<hidl_vec<uint8_t>>>&& hidlResult) {
                     auto& [ret, certChain] = hidlResult;
-                    // shedule temp key for deletion
+                    // schedule temp key for deletion
                     dev->deleteKey(std::move(hidlKeyBlob), [](Return<ErrorCode> rc) {
                         // log error but don't return an error
                         KS_HANDLE_HIDL_ERROR(rc);
                     });
                     if (!rc.isOk()) {
-                        resultPromise.set_value(ResponseCode::SYSTEM_ERROR);
+                        cb->onFinished(KeyStoreServiceReturnCode(ResponseCode::SYSTEM_ERROR), {});
                         return;
                     }
-                    if (ret == ErrorCode::OK && chain) {
-                        *chain =
-                            ::android::security::keymaster::KeymasterCertificateChain(certChain);
+                    if (ret == ErrorCode::OK) {
+                        cb->onFinished(
+                            KeyStoreServiceReturnCode(ret),
+                            ::android::security::keymaster::KeymasterCertificateChain(certChain));
+                    } else {
+                        cb->onFinished(KeyStoreServiceReturnCode(ret), {});
                     }
-                    resultPromise.set_value(ret);
                 });
         });
 
-    resultFuture.wait();
-    *aidl_return = static_cast<int32_t>(resultFuture.get());
-    return Status::ok();
+    return AIDL_RETURN(ResponseCode::NO_ERROR);
 }
 
 Status KeyStoreService::onDeviceOffBody(int32_t* aidl_return) {
@@ -1157,14 +1084,12 @@
     return Status::ok();
 }
 
-#define AIDL_RETURN(rc)                                                                            \
-    (*_aidl_return = static_cast<int32_t>(KeyStoreServiceReturnCode(rc)), Status::ok())
-
 Status KeyStoreService::importWrappedKey(
+    const ::android::sp<::android::security::keystore::IKeystoreKeyCharacteristicsCallback>& cb,
     const ::android::String16& wrappedKeyAlias, const ::std::vector<uint8_t>& wrappedKey,
     const ::android::String16& wrappingKeyAlias, const ::std::vector<uint8_t>& maskingKey,
     const KeymasterArguments& params, int64_t rootSid, int64_t fingerprintSid,
-    ::android::security::keymaster::KeyCharacteristics* outCharacteristics, int32_t* _aidl_return) {
+    int32_t* _aidl_return) {
 
     uid_t callingUid = IPCThreadState::self()->getCallingUid();
 
@@ -1198,22 +1123,15 @@
         return AIDL_RETURN(ErrorCode::HARDWARE_TYPE_UNAVAILABLE);
     }
 
-    std::promise<KeyStoreServiceReturnCode> resultPromise;
-    auto resultFuture = resultPromise.get_future();
-
     dev->importWrappedKey(
         std::move(wrappingLockedEntry), std::move(wrappedLockedEntry), wrappedKey, maskingKey,
         params.getParameters(), std::move(wrappingKeyBlob), std::move(wrappingCharBlob), rootSid,
-        fingerprintSid, [&](KeyStoreServiceReturnCode rc, KeyCharacteristics keyCharacteristics) {
-            if (rc.isOk() && outCharacteristics) {
-                *outCharacteristics =
-                    ::android::security::keymaster::KeyCharacteristics(keyCharacteristics);
-            }
-            resultPromise.set_value(rc);
+        fingerprintSid, [cb](KeyStoreServiceReturnCode rc, KeyCharacteristics keyCharacteristics) {
+            cb->onFinished(rc,
+                           ::android::security::keymaster::KeyCharacteristics(keyCharacteristics));
         });
 
-    resultFuture.wait();
-    return AIDL_RETURN(resultFuture.get());
+    return AIDL_RETURN(ResponseCode::NO_ERROR);
 }
 
 Status KeyStoreService::presentConfirmationPrompt(const sp<IBinder>& listener,
diff --git a/keystore/key_store_service.h b/keystore/key_store_service.h
index 29369d0..601ed21 100644
--- a/keystore/key_store_service.h
+++ b/keystore/key_store_service.h
@@ -17,7 +17,7 @@
 #ifndef KEYSTORE_KEYSTORE_SERVICE_H_
 #define KEYSTORE_KEYSTORE_SERVICE_H_
 
-#include <android/security/BnKeystoreService.h>
+#include <android/security/keystore/BnKeystoreService.h>
 
 #include "auth_token_table.h"
 #include "confirmation_manager.h"
@@ -42,7 +42,7 @@
 // java/android/security/IKeystoreService.aidl Note that all generated methods return binder::Status
 // and use last arguments to send actual result to the caller. Private methods don't need to handle
 // binder::Status. Input parameters cannot be null unless annotated with @nullable in .aidl file.
-class KeyStoreService : public android::security::BnKeystoreService {
+class KeyStoreService : public android::security::keystore::BnKeystoreService {
   public:
     explicit KeyStoreService(sp<KeyStore> keyStore) : mKeyStore(keyStore) {}
     virtual ~KeyStoreService() = default;
@@ -78,71 +78,76 @@
     ::android::binder::Status is_hardware_backed(const ::android::String16& string,
                                                  int32_t* _aidl_return) override;
     ::android::binder::Status clear_uid(int64_t uid, int32_t* _aidl_return) override;
-    ::android::binder::Status addRngEntropy(const ::std::vector<uint8_t>& data, int32_t flags,
-                                            int32_t* _aidl_return) override;
     ::android::binder::Status
-    generateKey(const ::android::String16& alias,
-                const ::android::security::keymaster::KeymasterArguments& arguments,
-                const ::std::vector<uint8_t>& entropy, int32_t uid, int32_t flags,
-                ::android::security::keymaster::KeyCharacteristics* characteristics,
-                int32_t* _aidl_return) override;
+    addRngEntropy(const ::android::sp<::android::security::keystore::IKeystoreResponseCallback>& cb,
+                  const ::std::vector<uint8_t>& data, int32_t flags,
+                  int32_t* _aidl_return) override;
+    ::android::binder::Status generateKey(
+        const ::android::sp<::android::security::keystore::IKeystoreKeyCharacteristicsCallback>& cb,
+        const ::android::String16& alias,
+        const ::android::security::keymaster::KeymasterArguments& arguments,
+        const ::std::vector<uint8_t>& entropy, int32_t uid, int32_t flags,
+        int32_t* _aidl_return) override;
+    ::android::binder::Status getKeyCharacteristics(
+        const ::android::sp<::android::security::keystore::IKeystoreKeyCharacteristicsCallback>& cb,
+        const ::android::String16& alias,
+        const ::android::security::keymaster::KeymasterBlob& clientId,
+        const ::android::security::keymaster::KeymasterBlob& appId, int32_t uid,
+        int32_t* _aidl_return) override;
+    ::android::binder::Status importKey(
+        const ::android::sp<::android::security::keystore::IKeystoreKeyCharacteristicsCallback>& cb,
+        const ::android::String16& alias,
+        const ::android::security::keymaster::KeymasterArguments& arguments, int32_t format,
+        const ::std::vector<uint8_t>& keyData, int32_t uid, int32_t flags,
+        int32_t* _aidl_return) override;
     ::android::binder::Status
-    getKeyCharacteristics(const ::android::String16& alias,
-                          const ::android::security::keymaster::KeymasterBlob& clientId,
-                          const ::android::security::keymaster::KeymasterBlob& appId, int32_t uid,
-                          ::android::security::keymaster::KeyCharacteristics* characteristics,
-                          int32_t* _aidl_return) override;
-    ::android::binder::Status
-    importKey(const ::android::String16& alias,
-              const ::android::security::keymaster::KeymasterArguments& arguments, int32_t format,
-              const ::std::vector<uint8_t>& keyData, int32_t uid, int32_t flags,
-              ::android::security::keymaster::KeyCharacteristics* characteristics,
-              int32_t* _aidl_return) override;
-    ::android::binder::Status
-    exportKey(const ::android::String16& alias, int32_t format,
+    exportKey(const ::android::sp<::android::security::keystore::IKeystoreExportKeyCallback>& cb,
+              const ::android::String16& alias, int32_t format,
               const ::android::security::keymaster::KeymasterBlob& clientId,
               const ::android::security::keymaster::KeymasterBlob& appId, int32_t uid,
-              ::android::security::keymaster::ExportResult* _aidl_return) override;
+              int32_t* _aidl_return) override;
     ::android::binder::Status
-    begin(const ::android::sp<::android::IBinder>& appToken, const ::android::String16& alias,
+    begin(const ::android::sp<::android::security::keystore::IKeystoreOperationResultCallback>& cb,
+          const ::android::sp<::android::IBinder>& appToken, const ::android::String16& alias,
           int32_t purpose, bool pruneable,
           const ::android::security::keymaster::KeymasterArguments& params,
-          const ::std::vector<uint8_t>& entropy, int32_t uid,
-          ::android::security::keymaster::OperationResult* _aidl_return) override;
+          const ::std::vector<uint8_t>& entropy, int32_t uid, int32_t* _aidl_return) override;
     ::android::binder::Status
-    update(const ::android::sp<::android::IBinder>& token,
+    update(const ::android::sp<::android::security::keystore::IKeystoreOperationResultCallback>& cb,
+           const ::android::sp<::android::IBinder>& token,
            const ::android::security::keymaster::KeymasterArguments& params,
-           const ::std::vector<uint8_t>& input,
-           ::android::security::keymaster::OperationResult* _aidl_return) override;
+           const ::std::vector<uint8_t>& input, int32_t* _aidl_return) override;
     ::android::binder::Status
-    finish(const ::android::sp<::android::IBinder>& token,
+    finish(const ::android::sp<::android::security::keystore::IKeystoreOperationResultCallback>& cb,
+           const ::android::sp<::android::IBinder>& token,
            const ::android::security::keymaster::KeymasterArguments& params,
            const ::std::vector<uint8_t>& signature, const ::std::vector<uint8_t>& entropy,
-           ::android::security::keymaster::OperationResult* _aidl_return) override;
-    ::android::binder::Status abort(const ::android::sp<::android::IBinder>& handle,
-                                    int32_t* _aidl_return) override;
+           int32_t* _aidl_return) override;
+    ::android::binder::Status
+    abort(const ::android::sp<::android::security::keystore::IKeystoreResponseCallback>& cb,
+          const ::android::sp<::android::IBinder>& token, int32_t* _aidl_return) override;
     ::android::binder::Status addAuthToken(const ::std::vector<uint8_t>& authToken,
                                            int32_t* _aidl_return) override;
     ::android::binder::Status onUserAdded(int32_t userId, int32_t parentId,
                                           int32_t* _aidl_return) override;
     ::android::binder::Status onUserRemoved(int32_t userId, int32_t* _aidl_return) override;
-    ::android::binder::Status
-    attestKey(const ::android::String16& alias,
-              const ::android::security::keymaster::KeymasterArguments& params,
-              ::android::security::keymaster::KeymasterCertificateChain* chain,
-              int32_t* _aidl_return) override;
-    ::android::binder::Status
-    attestDeviceIds(const ::android::security::keymaster::KeymasterArguments& params,
-                    ::android::security::keymaster::KeymasterCertificateChain* chain,
-                    int32_t* _aidl_return) override;
+    ::android::binder::Status attestKey(
+        const ::android::sp<::android::security::keystore::IKeystoreCertificateChainCallback>& cb,
+        const ::android::String16& alias,
+        const ::android::security::keymaster::KeymasterArguments& params,
+        int32_t* _aidl_return) override;
+    ::android::binder::Status attestDeviceIds(
+        const ::android::sp<::android::security::keystore::IKeystoreCertificateChainCallback>& cb,
+        const ::android::security::keymaster::KeymasterArguments& params,
+        int32_t* _aidl_return) override;
     ::android::binder::Status onDeviceOffBody(int32_t* _aidl_return) override;
 
     ::android::binder::Status importWrappedKey(
+        const ::android::sp<::android::security::keystore::IKeystoreKeyCharacteristicsCallback>& cb,
         const ::android::String16& wrappedKeyAlias, const ::std::vector<uint8_t>& wrappedKey,
         const ::android::String16& wrappingKeyAlias, const ::std::vector<uint8_t>& maskingKey,
         const ::android::security::keymaster::KeymasterArguments& params, int64_t rootSid,
-        int64_t fingerprintSid, ::android::security::keymaster::KeyCharacteristics* characteristics,
-        int32_t* _aidl_return) override;
+        int64_t fingerprintSid, int32_t* _aidl_return) override;
 
     ::android::binder::Status presentConfirmationPrompt(
         const ::android::sp<::android::IBinder>& listener, const ::android::String16& promptText,
diff --git a/keystore/keystore_aidl_hidl_marshalling_utils.cpp b/keystore/keystore_aidl_hidl_marshalling_utils.cpp
index db9b983..cdeaf32 100644
--- a/keystore/keystore_aidl_hidl_marshalling_utils.cpp
+++ b/keystore/keystore_aidl_hidl_marshalling_utils.cpp
@@ -21,14 +21,13 @@
 #include <keystore/KeyCharacteristics.h>
 #include <keystore/KeymasterBlob.h>
 #include <keystore/KeymasterCertificateChain.h>
-#include <keystore/KeystoreArg.h>
 #include <keystore/keymaster_types.h>
 #include <keystore/keystore_hidl_support.h>
 
 namespace keystore {
 
 // reads byte[]
-hidl_vec<uint8_t> readKeymasterBlob(const android::Parcel& in, bool inPlace) {
+hidl_vec<uint8_t> readKeymasterBlob(const android::Parcel& in) {
 
     ssize_t length = in.readInt32();
     if (length <= 0) {
@@ -38,7 +37,7 @@
     const void* buf = in.readInplace(length);
     if (!buf) return {};
 
-    return blob2hidlVec(reinterpret_cast<const uint8_t*>(buf), size_t(length), inPlace);
+    return blob2hidlVec(reinterpret_cast<const uint8_t*>(buf), size_t(length));
 }
 
 android::status_t writeKeymasterBlob(const hidl_vec<uint8_t>& blob, android::Parcel* out) {
@@ -235,7 +234,7 @@
 }
 
 status_t KeymasterBlob::readFromParcel(const Parcel* in) {
-    data_ = keystore::readKeymasterBlob(*in, true /* in place */);
+    data_ = keystore::readKeymasterBlob(*in);
     return OK;
 }
 
diff --git a/keystore/keystore_aidl_hidl_marshalling_utils.h b/keystore/keystore_aidl_hidl_marshalling_utils.h
index 13edbd2..ea72197 100644
--- a/keystore/keystore_aidl_hidl_marshalling_utils.h
+++ b/keystore/keystore_aidl_hidl_marshalling_utils.h
@@ -60,7 +60,7 @@
 /**
  * makes a copy only if inPlace is false
  */
-hidl_vec<uint8_t> readKeymasterBlob(const android::Parcel& in, bool inPlace = true);
+hidl_vec<uint8_t> readKeymasterBlob(const android::Parcel& in);
 android::status_t writeKeymasterBlob(const hidl_vec<uint8_t>& blob, android::Parcel* out);
 
 NullOr<hidl_vec<uint8_t>> readBlobAsByteArray(const android::Parcel& in, bool inPlace = true);
diff --git a/keystore/keystore_cli.cpp b/keystore/keystore_cli.cpp
index b58735e..2705a19 100644
--- a/keystore/keystore_cli.cpp
+++ b/keystore/keystore_cli.cpp
@@ -20,7 +20,7 @@
 #include <sys/types.h>
 #include <vector>
 
-#include <android/security/IKeystoreService.h>
+#include <android/security/keystore/IKeystoreService.h>
 #include <binder/IPCThreadState.h>
 #include <binder/IServiceManager.h>
 
@@ -28,7 +28,7 @@
 
 using namespace android;
 using namespace keystore;
-using android::security::IKeystoreService;
+using android::security::keystore::IKeystoreService;
 
 static const char* responses[] = {
     nullptr,
diff --git a/keystore/keystore_cli_v2.cpp b/keystore/keystore_cli_v2.cpp
index 157417f..0981f1e 100644
--- a/keystore/keystore_cli_v2.cpp
+++ b/keystore/keystore_cli_v2.cpp
@@ -29,7 +29,7 @@
 
 #include <android/hardware/confirmationui/1.0/types.h>
 #include <android/security/BnConfirmationPromptCallback.h>
-#include <android/security/IKeystoreService.h>
+#include <android/security/keystore/IKeystoreService.h>
 
 #include <binder/IPCThreadState.h>
 #include <binder/IServiceManager.h>
@@ -41,7 +41,7 @@
 
 using android::sp;
 using android::String16;
-using android::security::IKeystoreService;
+using android::security::keystore::IKeystoreService;
 using base::CommandLine;
 using ConfirmationResponseCode = android::hardware::confirmationui::V1_0::ResponseCode;
 
diff --git a/keystore/keystore_client_impl.cpp b/keystore/keystore_client_impl.cpp
index 6d998ad..18e9eb1 100644
--- a/keystore/keystore_client_impl.cpp
+++ b/keystore/keystore_client_impl.cpp
@@ -16,10 +16,11 @@
 
 #include "keystore/keystore_client_impl.h"
 
+#include <future>
 #include <string>
 #include <vector>
 
-#include <android/security/IKeystoreService.h>
+#include <android/security/keystore/IKeystoreService.h>
 #include <binder/IBinder.h>
 #include <binder/IInterface.h>
 #include <binder/IServiceManager.h>
@@ -30,6 +31,7 @@
 
 #include <keystore/keymaster_types.h>
 #include <keystore/keystore_hidl_support.h>
+#include <keystore/keystore_promises.h>
 
 #include "keystore_client.pb.h"
 
@@ -46,6 +48,7 @@
 using android::String16;
 using android::security::keymaster::ExportResult;
 using android::security::keymaster::OperationResult;
+using android::security::keystore::KeystoreResponse;
 using keystore::AuthorizationSet;
 using keystore::AuthorizationSetBuilder;
 using keystore::KeyCharacteristics;
@@ -57,7 +60,8 @@
 KeystoreClientImpl::KeystoreClientImpl() {
     service_manager_ = android::defaultServiceManager();
     keystore_binder_ = service_manager_->getService(String16("android.security.keystore"));
-    keystore_ = android::interface_cast<android::security::IKeystoreService>(keystore_binder_);
+    keystore_ =
+        android::interface_cast<android::security::keystore::IKeystoreService>(keystore_binder_);
 }
 
 bool KeystoreClientImpl::encryptWithAuthentication(const std::string& key_name,
@@ -180,10 +184,21 @@
 
 KeyStoreNativeReturnCode
 KeystoreClientImpl::addRandomNumberGeneratorEntropy(const std::string& entropy, int32_t flags) {
-    int32_t result;
-    auto binder_result = keystore_->addRngEntropy(blob2hidlVec(entropy), flags, &result);
+    int32_t error_code;
+
+    android::sp<KeystoreResponsePromise> promise(new KeystoreResponsePromise());
+    auto future = promise->get_future();
+
+    auto binder_result =
+        keystore_->addRngEntropy(promise, blob2hidlVec(entropy), flags, &error_code);
     if (!binder_result.isOk()) return ResponseCode::SYSTEM_ERROR;
-    return KeyStoreNativeReturnCode(result);
+
+    KeyStoreNativeReturnCode rc(error_code);
+    if (!rc.isOk()) return rc;
+
+    auto result = future.get();
+
+    return KeyStoreNativeReturnCode(result.response_code());
 }
 
 KeyStoreNativeReturnCode
@@ -191,19 +206,26 @@
                                 int32_t flags, AuthorizationSet* hardware_enforced_characteristics,
                                 AuthorizationSet* software_enforced_characteristics) {
     String16 key_name16(key_name.data(), key_name.size());
-    ::android::security::keymaster::KeyCharacteristics characteristics;
-    int32_t result;
+    int32_t error_code;
+    android::sp<KeyCharacteristicsPromise> promise(new KeyCharacteristicsPromise);
+    auto future = promise->get_future();
     auto binder_result = keystore_->generateKey(
-        key_name16, ::android::security::keymaster::KeymasterArguments(key_parameters.hidl_data()),
-        hidl_vec<uint8_t>() /* entropy */, kDefaultUID, flags, &characteristics, &result);
+        promise, key_name16,
+        ::android::security::keymaster::KeymasterArguments(key_parameters.hidl_data()),
+        hidl_vec<uint8_t>() /* entropy */, kDefaultUID, flags, &error_code);
     if (!binder_result.isOk()) return ResponseCode::SYSTEM_ERROR;
 
+    KeyStoreNativeReturnCode rc(error_code);
+    if (!rc.isOk()) return rc;
+
+    auto [km_response, characteristics] = future.get();
+
     /* assignment (hidl_vec<KeyParameter> -> AuthorizationSet) makes a deep copy.
      * There are no references to Parcel memory after that, and ownership of the newly acquired
      * memory is with the AuthorizationSet objects. */
     *hardware_enforced_characteristics = characteristics.hardwareEnforced.getParameters();
     *software_enforced_characteristics = characteristics.softwareEnforced.getParameters();
-    return KeyStoreNativeReturnCode(result);
+    return KeyStoreNativeReturnCode(km_response.response_code());
 }
 
 KeyStoreNativeReturnCode
@@ -211,18 +233,25 @@
                                           AuthorizationSet* hardware_enforced_characteristics,
                                           AuthorizationSet* software_enforced_characteristics) {
     String16 key_name16(key_name.data(), key_name.size());
-    ::android::security::keymaster::KeyCharacteristics characteristics;
-    int32_t result;
+    int32_t error_code;
+    android::sp<KeyCharacteristicsPromise> promise(new KeyCharacteristicsPromise);
+    auto future = promise->get_future();
     auto binder_result = keystore_->getKeyCharacteristics(
-        key_name16, android::security::keymaster::KeymasterBlob(),
-        android::security::keymaster::KeymasterBlob(), kDefaultUID, &characteristics, &result);
+        promise, key_name16, android::security::keymaster::KeymasterBlob(),
+        android::security::keymaster::KeymasterBlob(), kDefaultUID, &error_code);
+    if (!binder_result.isOk()) return ResponseCode::SYSTEM_ERROR;
+
+    KeyStoreNativeReturnCode rc(error_code);
+    if (!rc.isOk()) return rc;
+
+    auto [km_response, characteristics] = future.get();
 
     /* assignment (hidl_vec<KeyParameter> -> AuthorizationSet) makes a deep copy.
      * There are no references to Parcel memory after that, and ownership of the newly acquired
      * memory is with the AuthorizationSet objects. */
     *hardware_enforced_characteristics = characteristics.hardwareEnforced.getParameters();
     *software_enforced_characteristics = characteristics.softwareEnforced.getParameters();
-    return KeyStoreNativeReturnCode(result);
+    return KeyStoreNativeReturnCode(km_response.response_code());
 }
 
 KeyStoreNativeReturnCode
@@ -232,29 +261,48 @@
                               AuthorizationSet* software_enforced_characteristics) {
     String16 key_name16(key_name.data(), key_name.size());
     auto hidlKeyData = blob2hidlVec(key_data);
-    ::android::security::keymaster::KeyCharacteristics characteristics;
-    int32_t result;
+    int32_t error_code;
+    android::sp<KeyCharacteristicsPromise> promise(new KeyCharacteristicsPromise);
+    auto future = promise->get_future();
     auto binder_result = keystore_->importKey(
-        key_name16, ::android::security::keymaster::KeymasterArguments(key_parameters.hidl_data()),
-        (int)key_format, hidlKeyData, kDefaultUID, KEYSTORE_FLAG_NONE, &characteristics, &result);
+        promise, key_name16,
+        ::android::security::keymaster::KeymasterArguments(key_parameters.hidl_data()),
+        (int)key_format, hidlKeyData, kDefaultUID, KEYSTORE_FLAG_NONE, &error_code);
+    if (!binder_result.isOk()) return ResponseCode::SYSTEM_ERROR;
+
+    KeyStoreNativeReturnCode rc(error_code);
+    if (!rc.isOk()) return rc;
+
+    auto [km_response, characteristics] = future.get();
+
     /* assignment (hidl_vec<KeyParameter> -> AuthorizationSet) makes a deep copy.
      * There are no references to Parcel memory after that, and ownership of the newly acquired
      * memory is with the AuthorizationSet objects. */
     *hardware_enforced_characteristics = characteristics.hardwareEnforced.getParameters();
     *software_enforced_characteristics = characteristics.softwareEnforced.getParameters();
-    return KeyStoreNativeReturnCode(result);
+    return KeyStoreNativeReturnCode(km_response.response_code());
 }
 
 KeyStoreNativeReturnCode KeystoreClientImpl::exportKey(KeyFormat export_format,
                                                        const std::string& key_name,
                                                        std::string* export_data) {
     String16 key_name16(key_name.data(), key_name.size());
-    ExportResult export_result;
+    int32_t error_code;
+    android::sp<KeystoreExportPromise> promise(new KeystoreExportPromise);
+    auto future = promise->get_future();
     auto binder_result = keystore_->exportKey(
-        key_name16, (int)export_format, android::security::keymaster::KeymasterBlob(),
-        android::security::keymaster::KeymasterBlob(), kDefaultUID, &export_result);
+        promise, key_name16, (int)export_format, android::security::keymaster::KeymasterBlob(),
+        android::security::keymaster::KeymasterBlob(), kDefaultUID, &error_code);
     if (!binder_result.isOk()) return ResponseCode::SYSTEM_ERROR;
+
+    KeyStoreNativeReturnCode rc(error_code);
+    if (!rc.isOk()) return rc;
+
+    auto export_result = future.get();
+    if (!export_result.resultCode.isOk()) return export_result.resultCode;
+
     *export_data = hidlVec2String(export_result.exportData);
+
     return export_result.resultCode;
 }
 
@@ -279,12 +327,18 @@
                                    AuthorizationSet* output_parameters, uint64_t* handle) {
     android::sp<android::IBinder> token(new android::BBinder);
     String16 key_name16(key_name.data(), key_name.size());
-    OperationResult result;
+    int32_t error_code;
+    android::sp<OperationResultPromise> promise(new OperationResultPromise{});
+    auto future = promise->get_future();
     auto binder_result = keystore_->begin(
-        token, key_name16, (int)purpose, true /*pruneable*/,
+        promise, token, key_name16, (int)purpose, true /*pruneable*/,
         android::security::keymaster::KeymasterArguments(input_parameters.hidl_data()),
-        hidl_vec<uint8_t>() /* entropy */, kDefaultUID, &result);
+        hidl_vec<uint8_t>() /* entropy */, kDefaultUID, &error_code);
     if (!binder_result.isOk()) return ResponseCode::SYSTEM_ERROR;
+    KeyStoreNativeReturnCode rc(error_code);
+    if (!rc.isOk()) return rc;
+
+    OperationResult result = future.get();
     if (result.resultCode.isOk()) {
         *handle = getNextVirtualHandle();
         active_operations_[*handle] = result.token;
@@ -302,13 +356,19 @@
     if (active_operations_.count(handle) == 0) {
         return ErrorCode::INVALID_OPERATION_HANDLE;
     }
-    OperationResult result;
     auto hidlInputData = blob2hidlVec(input_data);
+    int32_t error_code;
+    android::sp<OperationResultPromise> promise(new OperationResultPromise{});
+    auto future = promise->get_future();
     auto binder_result = keystore_->update(
-        active_operations_[handle],
+        promise, active_operations_[handle],
         android::security::keymaster::KeymasterArguments(input_parameters.hidl_data()),
-        hidlInputData, &result);
+        hidlInputData, &error_code);
     if (!binder_result.isOk()) return ResponseCode::SYSTEM_ERROR;
+    KeyStoreNativeReturnCode rc(error_code);
+    if (!rc.isOk()) return rc;
+
+    OperationResult result = future.get();
 
     if (result.resultCode.isOk()) {
         *num_input_bytes_consumed = result.inputConsumed;
@@ -328,14 +388,19 @@
     if (active_operations_.count(handle) == 0) {
         return ErrorCode::INVALID_OPERATION_HANDLE;
     }
-    OperationResult result;
+    int32_t error_code;
     auto hidlSignature = blob2hidlVec(signature_to_verify);
+    android::sp<OperationResultPromise> promise(new OperationResultPromise{});
+    auto future = promise->get_future();
     auto binder_result = keystore_->finish(
-        active_operations_[handle],
+        promise, active_operations_[handle],
         android::security::keymaster::KeymasterArguments(input_parameters.hidl_data()),
-        (std::vector<uint8_t>)hidlSignature, hidl_vec<uint8_t>(), &result);
+        (std::vector<uint8_t>)hidlSignature, hidl_vec<uint8_t>(), &error_code);
     if (!binder_result.isOk()) return ResponseCode::SYSTEM_ERROR;
+    KeyStoreNativeReturnCode rc(error_code);
+    if (!rc.isOk()) return rc;
 
+    OperationResult result = future.get();
     if (result.resultCode.isOk()) {
         if (result.outParams.size()) {
             *output_parameters = result.outParams;
@@ -352,13 +417,18 @@
         return ErrorCode::INVALID_OPERATION_HANDLE;
     }
     int32_t result;
+    android::sp<KeystoreResponsePromise> promise(new KeystoreResponsePromise{});
+    auto future = promise->get_future();
     // Current implementation does not return exceptions in android::binder::Status
-    auto binder_result = keystore_->abort(active_operations_[handle], &result);
+    auto binder_result = keystore_->abort(promise, active_operations_[handle], &result);
     if (!binder_result.isOk()) return ResponseCode::SYSTEM_ERROR;
-    if (KeyStoreNativeReturnCode(result).isOk()) {
+    KeyStoreNativeReturnCode rc(result);
+    if (!rc.isOk()) return rc;
+    rc = KeyStoreNativeReturnCode(future.get().response_code());
+    if (rc.isOk()) {
         active_operations_.erase(handle);
     }
-    return KeyStoreNativeReturnCode(result);
+    return rc;
 }
 
 bool KeystoreClientImpl::doesKeyExist(const std::string& key_name) {
diff --git a/keystore/keystore_get.cpp b/keystore/keystore_get.cpp
index fec36c4..a6f8755 100644
--- a/keystore/keystore_get.cpp
+++ b/keystore/keystore_get.cpp
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-#include <android/security/IKeystoreService.h>
+#include <android/security/keystore/IKeystoreService.h>
 #include <binder/IServiceManager.h>
 
 #include <keystore/keystore_get.h>
@@ -26,8 +26,8 @@
 ssize_t keystore_get(const char* key, size_t keyLength, uint8_t** value) {
     sp<IServiceManager> sm = defaultServiceManager();
     sp<IBinder> binder = sm->getService(String16("android.security.keystore"));
-    sp<android::security::IKeystoreService> service =
-        interface_cast<android::security::IKeystoreService>(binder);
+    sp<android::security::keystore::IKeystoreService> service =
+        interface_cast<android::security::keystore::IKeystoreService>(binder);
 
     if (service == nullptr) {
         return -1;
diff --git a/keystore/keystore_main.cpp b/keystore/keystore_main.cpp
index c05d142..409ac83 100644
--- a/keystore/keystore_main.cpp
+++ b/keystore/keystore_main.cpp
@@ -18,7 +18,7 @@
 
 #include <android-base/logging.h>
 #include <android/hidl/manager/1.1/IServiceManager.h>
-#include <android/security/IKeystoreService.h>
+#include <android/security/keystore/IKeystoreService.h>
 #include <android/system/wifi/keystore/1.0/IKeystore.h>
 #include <binder/IPCThreadState.h>
 #include <binder/IServiceManager.h>
diff --git a/keystore/keystore_utils.cpp b/keystore/keystore_utils.cpp
index 71e8ed2..78056d6 100644
--- a/keystore/keystore_utils.cpp
+++ b/keystore/keystore_utils.cpp
@@ -107,8 +107,7 @@
 namespace keystore {
 
 hidl_vec<uint8_t> blob2hidlVec(const Blob& blob) {
-    hidl_vec<uint8_t> result;
-    result.setToExternal(const_cast<uint8_t*>(blob.getValue()), blob.getLength());
+    hidl_vec<uint8_t> result(blob.getValue(), blob.getValue() + blob.getLength());
     return result;
 }
 
diff --git a/keystore/legacy_keymaster_device_wrapper.cpp b/keystore/legacy_keymaster_device_wrapper.cpp
index 1f1aa96..4073b42 100644
--- a/keystore/legacy_keymaster_device_wrapper.cpp
+++ b/keystore/legacy_keymaster_device_wrapper.cpp
@@ -132,14 +132,18 @@
 }
 
 inline static hidl_vec<uint8_t> kmBlob2hidlVec(const keymaster_key_blob_t& blob) {
-    hidl_vec<uint8_t> result;
-    result.setToExternal(const_cast<unsigned char*>(blob.key_material), blob.key_material_size);
-    return result;
+    if (blob.key_material == nullptr || blob.key_material_size == 0) {
+        return {};
+    } else {
+        return hidl_vec<uint8_t>(blob.key_material, blob.key_material + blob.key_material_size);
+    }
 }
 inline static hidl_vec<uint8_t> kmBlob2hidlVec(const keymaster_blob_t& blob) {
-    hidl_vec<uint8_t> result;
-    result.setToExternal(const_cast<unsigned char*>(blob.data), blob.data_length);
-    return result;
+    if (blob.data == nullptr || blob.data_length == 0) {
+        return {};
+    } else {
+        return hidl_vec<uint8_t>(blob.data, blob.data + blob.data_length);
+    }
 }
 
 inline static hidl_vec<hidl_vec<uint8_t>>
@@ -186,8 +190,7 @@
             break;
         case KM_BIGNUM:
         case KM_BYTES:
-            result[i].blob.setToExternal(const_cast<unsigned char*>(params[i].blob.data),
-                                         params[i].blob.data_length);
+            result[i].blob = kmBlob2hidlVec(params[i].blob);
             break;
         case KM_INVALID:
         default: