diff --git a/config/hiddenapi-light-greylist.txt b/config/hiddenapi-light-greylist.txt
index ce0f945..374a336 100644
--- a/config/hiddenapi-light-greylist.txt
+++ b/config/hiddenapi-light-greylist.txt
@@ -1392,18 +1392,6 @@
 Landroid/security/Credentials;->convertToPem([Ljava/security/cert/Certificate;)[B
 Landroid/security/IKeyChainService$Stub;->asInterface(Landroid/os/IBinder;)Landroid/security/IKeyChainService;
 Landroid/security/IKeyChainService;->requestPrivateKey(Ljava/lang/String;)Ljava/lang/String;
-Landroid/security/IKeystoreService$Stub;->asInterface(Landroid/os/IBinder;)Landroid/security/IKeystoreService;
-Landroid/security/IKeystoreService;->clear_uid(J)I
-Landroid/security/IKeystoreService;->del(Ljava/lang/String;I)I
-Landroid/security/IKeystoreService;->exist(Ljava/lang/String;I)I
-Landroid/security/IKeystoreService;->generateKey(Ljava/lang/String;Landroid/security/keymaster/KeymasterArguments;[BIILandroid/security/keymaster/KeyCharacteristics;)I
-Landroid/security/IKeystoreService;->get(Ljava/lang/String;I)[B
-Landroid/security/IKeystoreService;->getState(I)I
-Landroid/security/IKeystoreService;->insert(Ljava/lang/String;[BII)I
-Landroid/security/IKeystoreService;->is_hardware_backed(Ljava/lang/String;)I
-Landroid/security/IKeystoreService;->list(Ljava/lang/String;I)[Ljava/lang/String;
-Landroid/security/IKeystoreService;->reset()I
-Landroid/security/IKeystoreService;->ungrant(Ljava/lang/String;I)I
 Landroid/security/keymaster/KeymasterBlobArgument;-><init>(ILandroid/os/Parcel;)V
 Landroid/security/keymaster/KeymasterBlobArgument;-><init>(I[B)V
 Landroid/security/keymaster/KeymasterBlobArgument;->blob:[B
@@ -1415,6 +1403,17 @@
 Landroid/security/keymaster/KeymasterLongArgument;-><init>(IJ)V
 Landroid/security/keymaster/KeymasterLongArgument;-><init>(ILandroid/os/Parcel;)V
 Landroid/security/keymaster/KeymasterLongArgument;->value:J
+Landroid/security/keystore/IKeystoreService$Stub;->asInterface(Landroid/os/IBinder;)Landroid/security/keystore/IKeystoreService;
+Landroid/security/keystore/IKeystoreService;->clear_uid(J)I
+Landroid/security/keystore/IKeystoreService;->del(Ljava/lang/String;I)I
+Landroid/security/keystore/IKeystoreService;->exist(Ljava/lang/String;I)I
+Landroid/security/keystore/IKeystoreService;->get(Ljava/lang/String;I)[B
+Landroid/security/keystore/IKeystoreService;->getState(I)I
+Landroid/security/keystore/IKeystoreService;->insert(Ljava/lang/String;[BII)I
+Landroid/security/keystore/IKeystoreService;->is_hardware_backed(Ljava/lang/String;)I
+Landroid/security/keystore/IKeystoreService;->list(Ljava/lang/String;I)[Ljava/lang/String;
+Landroid/security/keystore/IKeystoreService;->reset()I
+Landroid/security/keystore/IKeystoreService;->ungrant(Ljava/lang/String;I)I
 Landroid/service/carrier/ICarrierMessagingCallback$Stub;-><init>()V
 Landroid/service/carrier/ICarrierMessagingService;->filterSms(Landroid/service/carrier/MessagePdu;Ljava/lang/String;IILandroid/service/carrier/ICarrierMessagingCallback;)V
 Landroid/service/dreams/IDreamManager$Stub;->asInterface(Landroid/os/IBinder;)Landroid/service/dreams/IDreamManager;
diff --git a/core/java/android/security/keymaster/ExportResult.java b/core/java/android/security/keymaster/ExportResult.java
index c104671..1ab79fb 100644
--- a/core/java/android/security/keymaster/ExportResult.java
+++ b/core/java/android/security/keymaster/ExportResult.java
@@ -28,6 +28,11 @@
     public final int resultCode;
     public final byte[] exportData;
 
+    public ExportResult(int resultCode) {
+        this.resultCode = resultCode;
+        this.exportData = new byte[0];
+    }
+
     @UnsupportedAppUsage
     public static final Parcelable.Creator<ExportResult> CREATOR = new
             Parcelable.Creator<ExportResult>() {
diff --git a/core/java/android/security/keymaster/KeyCharacteristics.java b/core/java/android/security/keymaster/KeyCharacteristics.java
index 555863e..a4fe75d 100644
--- a/core/java/android/security/keymaster/KeyCharacteristics.java
+++ b/core/java/android/security/keymaster/KeyCharacteristics.java
@@ -52,6 +52,14 @@
         readFromParcel(in);
     }
 
+    /**
+     * Makes a shallow copy of other by copying the other's references to the KeymasterArguments
+     */
+    public void shallowCopyFrom(KeyCharacteristics other) {
+        this.swEnforced = other.swEnforced;
+        this.hwEnforced = other.hwEnforced;
+    }
+
     @Override
     public int describeContents() {
         return 0;
diff --git a/core/java/android/security/keymaster/KeymasterCertificateChain.java b/core/java/android/security/keymaster/KeymasterCertificateChain.java
index 243b9fe..00a1a1c 100644
--- a/core/java/android/security/keymaster/KeymasterCertificateChain.java
+++ b/core/java/android/security/keymaster/KeymasterCertificateChain.java
@@ -54,6 +54,14 @@
         readFromParcel(in);
     }
 
+    /**
+     * Makes a shallow copy of other by copying the reference to the certificate chain list.
+     * @param other
+     */
+    public void shallowCopyFrom(KeymasterCertificateChain other) {
+        this.mCertificates = other.mCertificates;
+    }
+
     public List<byte[]> getCertificates() {
         return mCertificates;
     }
diff --git a/core/java/android/security/keymaster/OperationResult.java b/core/java/android/security/keymaster/OperationResult.java
index 2943211..bc4f360 100644
--- a/core/java/android/security/keymaster/OperationResult.java
+++ b/core/java/android/security/keymaster/OperationResult.java
@@ -59,6 +59,10 @@
         this.outParams = outParams;
     }
 
+    public OperationResult(int resultCode) {
+        this(resultCode, null, 0, 0, null, null);
+    }
+
     protected OperationResult(Parcel in) {
         resultCode = in.readInt();
         token = in.readStrongBinder();
diff --git a/keystore/java/android/security/KeyStore.java b/keystore/java/android/security/KeyStore.java
index 4e01883..2d214a7 100644
--- a/keystore/java/android/security/KeyStore.java
+++ b/keystore/java/android/security/KeyStore.java
@@ -38,11 +38,13 @@
 import android.security.keymaster.KeymasterCertificateChain;
 import android.security.keymaster.KeymasterDefs;
 import android.security.keymaster.OperationResult;
+import android.security.keystore.IKeystoreService;
 import android.security.keystore.KeyExpiredException;
 import android.security.keystore.KeyNotYetValidException;
 import android.security.keystore.KeyPermanentlyInvalidatedException;
 import android.security.keystore.KeyProperties;
 import android.security.keystore.KeyProtection;
+import android.security.keystore.KeystoreResponse;
 import android.security.keystore.StrongBoxUnavailableException;
 import android.security.keystore.UserNotAuthenticatedException;
 import android.util.Log;
@@ -54,6 +56,8 @@
 import java.security.InvalidKeyException;
 import java.util.List;
 import java.util.Locale;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
 import sun.security.util.ObjectIdentifier;
 import sun.security.x509.AlgorithmId;
 
@@ -440,27 +444,107 @@
 
     public boolean addRngEntropy(byte[] data, int flags) {
         try {
-            return mBinder.addRngEntropy(data, flags) == NO_ERROR;
+            KeystoreResultPromise promise = new KeystoreResultPromise();
+            int errorCode = mBinder.addRngEntropy(promise, data, flags);
+            if (errorCode == NO_ERROR) {
+                return promise.getFuture().get().getErrorCode() == NO_ERROR;
+            } else {
+                return false;
+            }
         } catch (RemoteException e) {
             Log.w(TAG, "Cannot connect to keystore", e);
             return false;
+        } catch (ExecutionException | InterruptedException e) {
+            Log.e(TAG, "AddRngEntropy completed with exception", e);
+            return false;
         }
     }
 
+    private class KeyCharacteristicsCallbackResult {
+        private KeystoreResponse keystoreResponse;
+        private KeyCharacteristics keyCharacteristics;
+
+        public KeyCharacteristicsCallbackResult(KeystoreResponse keystoreResponse,
+                                                KeyCharacteristics keyCharacteristics) {
+            this.keystoreResponse = keystoreResponse;
+            this.keyCharacteristics = keyCharacteristics;
+        }
+
+        public KeystoreResponse getKeystoreResponse() {
+            return keystoreResponse;
+        }
+
+        public void setKeystoreResponse(KeystoreResponse keystoreResponse) {
+            this.keystoreResponse = keystoreResponse;
+        }
+
+        public KeyCharacteristics getKeyCharacteristics() {
+            return keyCharacteristics;
+        }
+
+        public void setKeyCharacteristics(KeyCharacteristics keyCharacteristics) {
+            this.keyCharacteristics = keyCharacteristics;
+        }
+    }
+
+    private class KeyCharacteristicsPromise
+    extends android.security.keystore.IKeystoreKeyCharacteristicsCallback.Stub {
+        final private CompletableFuture<KeyCharacteristicsCallbackResult> future =
+                new CompletableFuture<KeyCharacteristicsCallbackResult>();
+        @Override
+        public void onFinished(KeystoreResponse keystoreResponse,
+                               KeyCharacteristics keyCharacteristics)
+                                       throws android.os.RemoteException {
+            future.complete(
+                    new KeyCharacteristicsCallbackResult(keystoreResponse, keyCharacteristics));
+        }
+        public final CompletableFuture<KeyCharacteristicsCallbackResult> getFuture() {
+            return future;
+        }
+    };
+
+    private int generateKeyInternal(String alias, KeymasterArguments args, byte[] entropy, int uid,
+            int flags, KeyCharacteristics outCharacteristics)
+                    throws RemoteException, ExecutionException, InterruptedException {
+        KeyCharacteristicsPromise promise = new KeyCharacteristicsPromise();
+        int error = mBinder.generateKey(promise, alias, args, entropy, uid, flags);
+        if (error != NO_ERROR) {
+            Log.e(TAG, "generateKeyInternal failed on request " + error);
+            return error;
+        }
+
+        KeyCharacteristicsCallbackResult result = promise.getFuture().get();
+        error = result.getKeystoreResponse().getErrorCode();
+        if (error != NO_ERROR) {
+            Log.e(TAG, "generateKeyInternal failed on response " + error);
+            return error;
+        }
+        KeyCharacteristics characteristics = result.getKeyCharacteristics();
+        if (characteristics == null) {
+            Log.e(TAG, "generateKeyInternal got empty key cheractariestics " + error);
+            return SYSTEM_ERROR;
+        }
+        outCharacteristics.shallowCopyFrom(characteristics);
+        return NO_ERROR;
+    }
+
     public int generateKey(String alias, KeymasterArguments args, byte[] entropy, int uid,
             int flags, KeyCharacteristics outCharacteristics) {
         try {
             entropy = entropy != null ? entropy : new byte[0];
             args = args != null ? args : new KeymasterArguments();
-            int error = mBinder.generateKey(alias, args, entropy, uid, flags, outCharacteristics);
+            int error = generateKeyInternal(alias, args, entropy, uid, flags, outCharacteristics);
             if (error == KEY_ALREADY_EXISTS) {
                 mBinder.del(alias, uid);
-                error = mBinder.generateKey(alias, args, entropy, uid, flags, outCharacteristics);
+                error = generateKeyInternal(alias, args, entropy, uid, flags, outCharacteristics);
             }
             return error;
         } catch (RemoteException e) {
             Log.w(TAG, "Cannot connect to keystore", e);
             return SYSTEM_ERROR;
+        } catch (ExecutionException | InterruptedException e) {
+            Log.e(TAG, "generateKey completed with exception", e);
+            return SYSTEM_ERROR;
         }
     }
 
@@ -474,10 +558,24 @@
         try {
             clientId = clientId != null ? clientId : new KeymasterBlob(new byte[0]);
             appId = appId != null ? appId : new KeymasterBlob(new byte[0]);
-            return mBinder.getKeyCharacteristics(alias, clientId, appId, uid, outCharacteristics);
+            KeyCharacteristicsPromise promise = new KeyCharacteristicsPromise();
+            int error = mBinder.getKeyCharacteristics(promise, alias, clientId, appId, uid);
+            if (error != NO_ERROR) return error;
+
+            KeyCharacteristicsCallbackResult result = promise.getFuture().get();
+            error = result.getKeystoreResponse().getErrorCode();
+            if (error != NO_ERROR) return error;
+
+            KeyCharacteristics characteristics = result.getKeyCharacteristics();
+            if (characteristics == null) return SYSTEM_ERROR;
+            outCharacteristics.shallowCopyFrom(characteristics);
+            return NO_ERROR;
         } catch (RemoteException e) {
             Log.w(TAG, "Cannot connect to keystore", e);
             return SYSTEM_ERROR;
+        } catch (ExecutionException | InterruptedException e) {
+            Log.e(TAG, "GetKeyCharacteristics completed with exception", e);
+            return SYSTEM_ERROR;
         }
     }
 
@@ -486,20 +584,40 @@
         return getKeyCharacteristics(alias, clientId, appId, UID_SELF, outCharacteristics);
     }
 
+    private int importKeyInternal(String alias, KeymasterArguments args, int format, byte[] keyData,
+            int uid, int flags, KeyCharacteristics outCharacteristics)
+                    throws RemoteException, ExecutionException, InterruptedException {
+        KeyCharacteristicsPromise promise = new KeyCharacteristicsPromise();
+        int error = mBinder.importKey(promise, alias, args, format, keyData, uid, flags);
+        if (error != NO_ERROR) return error;
+
+        KeyCharacteristicsCallbackResult result = promise.getFuture().get();
+        error = result.getKeystoreResponse().getErrorCode();
+        if (error != NO_ERROR) return error;
+
+        KeyCharacteristics characteristics = result.getKeyCharacteristics();
+        if (characteristics == null) return SYSTEM_ERROR;
+        outCharacteristics.shallowCopyFrom(characteristics);
+        return NO_ERROR;
+    }
+
     public int importKey(String alias, KeymasterArguments args, int format, byte[] keyData,
             int uid, int flags, KeyCharacteristics outCharacteristics) {
         try {
-            int error = mBinder.importKey(alias, args, format, keyData, uid, flags,
+            int error = importKeyInternal(alias, args, format, keyData, uid, flags,
                     outCharacteristics);
             if (error == KEY_ALREADY_EXISTS) {
                 mBinder.del(alias, uid);
-                error = mBinder.importKey(alias, args, format, keyData, uid, flags,
+                error = importKeyInternal(alias, args, format, keyData, uid, flags,
                         outCharacteristics);
             }
             return error;
         } catch (RemoteException e) {
             Log.w(TAG, "Cannot connect to keystore", e);
             return SYSTEM_ERROR;
+        } catch (ExecutionException | InterruptedException e) {
+            Log.e(TAG, "ImportKey completed with exception", e);
+            return SYSTEM_ERROR;
         }
     }
 
@@ -567,34 +685,79 @@
         return true;
     }
 
+    private int importWrappedKeyInternal(String wrappedKeyAlias, byte[] wrappedKey,
+            String wrappingKeyAlias,
+            byte[] maskingKey, KeymasterArguments args, long rootSid, long fingerprintSid,
+            KeyCharacteristics outCharacteristics)
+                    throws RemoteException, ExecutionException, InterruptedException {
+        KeyCharacteristicsPromise promise = new KeyCharacteristicsPromise();
+        int error = mBinder.importWrappedKey(promise, wrappedKeyAlias, wrappedKey, wrappingKeyAlias,
+                maskingKey, args, rootSid, fingerprintSid);
+        if (error != NO_ERROR) return error;
+
+        KeyCharacteristicsCallbackResult result = promise.getFuture().get();
+        error = result.getKeystoreResponse().getErrorCode();
+        if (error != NO_ERROR) return error;
+
+        KeyCharacteristics characteristics = result.getKeyCharacteristics();
+        if (characteristics == null) return SYSTEM_ERROR;
+        outCharacteristics.shallowCopyFrom(characteristics);
+        return NO_ERROR;
+    }
+
     public int importWrappedKey(String wrappedKeyAlias, byte[] wrappedKey,
             String wrappingKeyAlias,
             byte[] maskingKey, KeymasterArguments args, long rootSid, long fingerprintSid, int uid,
             KeyCharacteristics outCharacteristics) {
+        // TODO b/119217337 uid parameter gets silently ignored.
         try {
-            int error = mBinder.importWrappedKey(wrappedKeyAlias, wrappedKey, wrappingKeyAlias,
+            int error = importWrappedKeyInternal(wrappedKeyAlias, wrappedKey, wrappingKeyAlias,
                     maskingKey, args, rootSid, fingerprintSid, outCharacteristics);
             if (error == KEY_ALREADY_EXISTS) {
-                mBinder.del(wrappedKeyAlias, -1);
-                error = mBinder.importWrappedKey(wrappedKeyAlias, wrappedKey, wrappingKeyAlias,
+                mBinder.del(wrappedKeyAlias, UID_SELF);
+                error = importWrappedKeyInternal(wrappedKeyAlias, wrappedKey, wrappingKeyAlias,
                         maskingKey, args, rootSid, fingerprintSid, outCharacteristics);
             }
             return error;
         } catch (RemoteException e) {
             Log.w(TAG, "Cannot connect to keystore", e);
             return SYSTEM_ERROR;
+        } catch (ExecutionException | InterruptedException e) {
+            Log.e(TAG, "ImportWrappedKey completed with exception", e);
+            return SYSTEM_ERROR;
         }
     }
 
+    private class ExportKeyPromise
+    extends android.security.keystore.IKeystoreExportKeyCallback.Stub {
+        final private CompletableFuture<ExportResult> future = new CompletableFuture<ExportResult>();
+        @Override
+        public void onFinished(ExportResult exportKeyResult) throws android.os.RemoteException {
+            future.complete(exportKeyResult);
+        }
+        public final CompletableFuture<ExportResult> getFuture() {
+            return future;
+        }
+    };
+
     public ExportResult exportKey(String alias, int format, KeymasterBlob clientId,
             KeymasterBlob appId, int uid) {
         try {
             clientId = clientId != null ? clientId : new KeymasterBlob(new byte[0]);
             appId = appId != null ? appId : new KeymasterBlob(new byte[0]);
-            return mBinder.exportKey(alias, format, clientId, appId, uid);
+            ExportKeyPromise promise = new ExportKeyPromise();
+            int error = mBinder.exportKey(promise, alias, format, clientId, appId, uid);
+            if (error == NO_ERROR) {
+                return promise.getFuture().get();
+            } else {
+                return new ExportResult(error);
+            }
         } catch (RemoteException e) {
             Log.w(TAG, "Cannot connect to keystore", e);
             return null;
+        } catch (ExecutionException | InterruptedException e) {
+            Log.e(TAG, "ExportKey completed with exception", e);
+            return null;
         }
     }
     public ExportResult exportKey(String alias, int format, KeymasterBlob clientId,
@@ -602,15 +765,37 @@
         return exportKey(alias, format, clientId, appId, UID_SELF);
     }
 
+    private class OperationPromise
+    extends android.security.keystore.IKeystoreOperationResultCallback.Stub {
+        final private CompletableFuture<OperationResult> future = new CompletableFuture<OperationResult>();
+        @Override
+        public void onFinished(OperationResult operationResult) throws android.os.RemoteException {
+            future.complete(operationResult);
+        }
+        public final CompletableFuture<OperationResult> getFuture() {
+            return future;
+        }
+    };
+
     public OperationResult begin(String alias, int purpose, boolean pruneable,
             KeymasterArguments args, byte[] entropy, int uid) {
         try {
             args = args != null ? args : new KeymasterArguments();
             entropy = entropy != null ? entropy : new byte[0];
-            return mBinder.begin(getToken(), alias, purpose, pruneable, args, entropy, uid);
+            OperationPromise promise = new OperationPromise();
+            int errorCode =  mBinder.begin(promise, getToken(), alias, purpose, pruneable, args,
+                                           entropy, uid);
+            if (errorCode == NO_ERROR) {
+                return promise.getFuture().get();
+            } else {
+                return new OperationResult(errorCode);
+            }
         } catch (RemoteException e) {
             Log.w(TAG, "Cannot connect to keystore", e);
             return null;
+        } catch (ExecutionException | InterruptedException e) {
+            Log.e(TAG, "Begin completed with exception", e);
+            return null;
         }
     }
 
@@ -625,10 +810,19 @@
         try {
             arguments = arguments != null ? arguments : new KeymasterArguments();
             input = input != null ? input : new byte[0];
-            return mBinder.update(token, arguments, input);
+            OperationPromise promise = new OperationPromise();
+            int errorCode =  mBinder.update(promise, token, arguments, input);
+            if (errorCode == NO_ERROR) {
+                return promise.getFuture().get();
+            } else {
+                return new OperationResult(errorCode);
+            }
         } catch (RemoteException e) {
             Log.w(TAG, "Cannot connect to keystore", e);
             return null;
+        } catch (ExecutionException | InterruptedException e) {
+            Log.e(TAG, "Update completed with exception", e);
+            return null;
         }
     }
 
@@ -638,10 +832,19 @@
             arguments = arguments != null ? arguments : new KeymasterArguments();
             entropy = entropy != null ? entropy : new byte[0];
             signature = signature != null ? signature : new byte[0];
-            return mBinder.finish(token, arguments, signature, entropy);
+            OperationPromise promise = new OperationPromise();
+            int errorCode = mBinder.finish(promise, token, arguments, signature, entropy);
+            if (errorCode == NO_ERROR) {
+                return promise.getFuture().get();
+            } else {
+                return new OperationResult(errorCode);
+            }
         } catch (RemoteException e) {
             Log.w(TAG, "Cannot connect to keystore", e);
             return null;
+        } catch (ExecutionException | InterruptedException e) {
+            Log.e(TAG, "Finish completed with exception", e);
+            return null;
         }
     }
 
@@ -649,12 +852,33 @@
         return finish(token, arguments, signature, null);
     }
 
+    private class KeystoreResultPromise
+    extends android.security.keystore.IKeystoreResponseCallback.Stub {
+        final private CompletableFuture<KeystoreResponse> future = new CompletableFuture<KeystoreResponse>();
+        @Override
+        public void onFinished(KeystoreResponse keystoreResponse) throws android.os.RemoteException {
+            future.complete(keystoreResponse);
+        }
+        public final CompletableFuture<KeystoreResponse> getFuture() {
+            return future;
+        }
+    };
+
     public int abort(IBinder token) {
         try {
-            return mBinder.abort(token);
+            KeystoreResultPromise promise = new KeystoreResultPromise();
+            int errorCode = mBinder.abort(promise, token);
+            if (errorCode == NO_ERROR) {
+                return promise.getFuture().get().getErrorCode();
+            } else {
+                return errorCode;
+            }
         } catch (RemoteException e) {
             Log.w(TAG, "Cannot connect to keystore", e);
             return SYSTEM_ERROR;
+        } catch (ExecutionException | InterruptedException e) {
+            Log.e(TAG, "Abort completed with exception", e);
+            return SYSTEM_ERROR;
         }
     }
 
@@ -736,6 +960,47 @@
         return onUserPasswordChanged(UserHandle.getUserId(Process.myUid()), newPassword);
     }
 
+    private class KeyAttestationCallbackResult {
+        private KeystoreResponse keystoreResponse;
+        private KeymasterCertificateChain certificateChain;
+
+        public KeyAttestationCallbackResult(KeystoreResponse keystoreResponse,
+                KeymasterCertificateChain certificateChain) {
+            this.keystoreResponse = keystoreResponse;
+            this.certificateChain = certificateChain;
+        }
+
+        public KeystoreResponse getKeystoreResponse() {
+            return keystoreResponse;
+        }
+
+        public void setKeystoreResponse(KeystoreResponse keystoreResponse) {
+            this.keystoreResponse = keystoreResponse;
+        }
+
+        public KeymasterCertificateChain getCertificateChain() {
+            return certificateChain;
+        }
+
+        public void setCertificateChain(KeymasterCertificateChain certificateChain) {
+            this.certificateChain = certificateChain;
+        }
+    }
+
+    private class CertificateChainPromise
+    extends android.security.keystore.IKeystoreCertificateChainCallback.Stub {
+        final private CompletableFuture<KeyAttestationCallbackResult> future = new CompletableFuture<KeyAttestationCallbackResult>();
+        @Override
+        public void onFinished(KeystoreResponse keystoreResponse,
+                KeymasterCertificateChain certificateChain) throws android.os.RemoteException {
+            future.complete(new KeyAttestationCallbackResult(keystoreResponse, certificateChain));
+        }
+        public final CompletableFuture<KeyAttestationCallbackResult> getFuture() {
+            return future;
+        }
+    };
+
+
     public int attestKey(
             String alias, KeymasterArguments params, KeymasterCertificateChain outChain) {
         try {
@@ -745,10 +1010,21 @@
             if (outChain == null) {
                 outChain = new KeymasterCertificateChain();
             }
-            return mBinder.attestKey(alias, params, outChain);
+            CertificateChainPromise promise = new CertificateChainPromise();
+            int error = mBinder.attestKey(promise, alias, params);
+            if (error != NO_ERROR) return error;
+            KeyAttestationCallbackResult result = promise.getFuture().get();
+            error = result.getKeystoreResponse().getErrorCode();
+            if (error == NO_ERROR) {
+                outChain.shallowCopyFrom(result.getCertificateChain());
+            }
+            return error;
         } catch (RemoteException e) {
             Log.w(TAG, "Cannot connect to keystore", e);
             return SYSTEM_ERROR;
+        } catch (ExecutionException | InterruptedException e) {
+            Log.e(TAG, "AttestKey completed with exception", e);
+            return SYSTEM_ERROR;
         }
     }
 
@@ -760,10 +1036,21 @@
             if (outChain == null) {
                 outChain = new KeymasterCertificateChain();
             }
-            return mBinder.attestDeviceIds(params, outChain);
+            CertificateChainPromise promise = new CertificateChainPromise();
+            int error = mBinder.attestDeviceIds(promise, params);
+            if (error != NO_ERROR) return error;
+            KeyAttestationCallbackResult result = promise.getFuture().get();
+            error = result.getKeystoreResponse().getErrorCode();
+            if (error == NO_ERROR) {
+                outChain.shallowCopyFrom(result.getCertificateChain());
+            }
+            return error;
         } catch (RemoteException e) {
             Log.w(TAG, "Cannot connect to keystore", e);
             return SYSTEM_ERROR;
+        } catch (ExecutionException | InterruptedException e) {
+            Log.e(TAG, "AttestDevicdeIds completed with exception", e);
+            return SYSTEM_ERROR;
         }
     }
 
diff --git a/keystore/java/android/security/keystore/KeystoreResponse.java b/keystore/java/android/security/keystore/KeystoreResponse.java
new file mode 100644
index 0000000..3a229cb
--- /dev/null
+++ b/keystore/java/android/security/keystore/KeystoreResponse.java
@@ -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.os.Parcel;
+import android.os.Parcelable;
+import android.os.ParcelFormatException;
+
+/**
+ * The Java side of the KeystoreResponse.
+ * <p>
+ * Serialization code for this and subclasses must be kept in sync with system/security/keystore.
+ * @hide
+ */
+public class KeystoreResponse implements Parcelable {
+    public final int error_code_;
+    public final String error_msg_;
+
+    public static final Parcelable.Creator<KeystoreResponse> CREATOR = new
+            Parcelable.Creator<KeystoreResponse>() {
+                @Override
+                public KeystoreResponse createFromParcel(Parcel in) {
+                    final int error_code = in.readInt();
+                    final String error_msg = in.readString();
+                    return new KeystoreResponse(error_code, error_msg);
+                }
+
+                @Override
+                public KeystoreResponse[] newArray(int size) {
+                    return new KeystoreResponse[size];
+                }
+            };
+
+    protected KeystoreResponse(int error_code, String error_msg) {
+        this.error_code_ = error_code;
+        this.error_msg_ = error_msg;
+    }
+
+    /**
+     * @return the error_code_
+     */
+    public final int getErrorCode() {
+        return error_code_;
+    }
+
+    /**
+     * @return the error_msg_
+     */
+    public final String getErrorMessage() {
+        return error_msg_;
+    }
+
+    
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel out, int flags) {
+        out.writeInt(error_code_);
+        out.writeString(error_msg_);
+    }
+}
diff --git a/services/core/java/com/android/server/policy/keyguard/KeyguardStateMonitor.java b/services/core/java/com/android/server/policy/keyguard/KeyguardStateMonitor.java
index a55b49f..f78d263 100644
--- a/services/core/java/com/android/server/policy/keyguard/KeyguardStateMonitor.java
+++ b/services/core/java/com/android/server/policy/keyguard/KeyguardStateMonitor.java
@@ -20,7 +20,7 @@
 import android.content.Context;
 import android.os.RemoteException;
 import android.os.ServiceManager;
-import android.security.IKeystoreService;
+import android.security.keystore.IKeystoreService;
 import android.util.Slog;
 
 import com.android.internal.policy.IKeyguardService;