diff --git a/app/app.iml b/app/app.iml
index 7f40c8022..b22393ffd 100644
--- a/app/app.iml
+++ b/app/app.iml
@@ -9,7 +9,6 @@
     <facet type="android" name="Android">
       <configuration>
         <option name="SELECTED_BUILD_VARIANT" value="flavor1Debug" />
-        <option name="SELECTED_TEST_ARTIFACT" value="_android_test_" />
         <option name="ASSEMBLE_TASK_NAME" value="assembleFlavor1Debug" />
         <option name="COMPILE_JAVA_TASK_NAME" value="compileFlavor1DebugSources" />
         <afterSyncTasks>
@@ -53,13 +52,6 @@
       <sourceFolder url="file://$MODULE_DIR$/src/flavor1Debug/java" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/src/flavor1Debug/renderscript" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/src/flavor1Debug/shaders" isTestSource="false" />
-      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/res" type="java-test-resource" />
-      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/resources" type="java-test-resource" />
-      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/assets" type="java-test-resource" />
-      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/aidl" isTestSource="true" />
-      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/java" isTestSource="true" />
-      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/rs" isTestSource="true" />
-      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/shaders" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/build/generated/source/r/androidTest/flavor1/debug" isTestSource="true" generated="true" />
       <sourceFolder url="file://$MODULE_DIR$/build/generated/source/aidl/androidTest/flavor1/debug" isTestSource="true" generated="true" />
       <sourceFolder url="file://$MODULE_DIR$/build/generated/source/buildConfig/androidTest/flavor1/debug" isTestSource="true" generated="true" />
@@ -67,6 +59,14 @@
       <sourceFolder url="file://$MODULE_DIR$/build/generated/source/apt/androidTest/flavor1/debug" isTestSource="true" generated="true" />
       <sourceFolder url="file://$MODULE_DIR$/build/generated/res/rs/androidTest/flavor1/debug" type="java-test-resource" />
       <sourceFolder url="file://$MODULE_DIR$/build/generated/res/resValues/androidTest/flavor1/debug" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/res" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/resources" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/assets" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/aidl" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/jni" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/rs" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1Debug/shaders" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/flavor1/res" type="java-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/flavor1/resources" type="java-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/flavor1/assets" type="java-resource" />
@@ -74,20 +74,22 @@
       <sourceFolder url="file://$MODULE_DIR$/src/flavor1/java" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/src/flavor1/renderscript" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/src/flavor1/shaders" isTestSource="false" />
-      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/res" type="java-test-resource" />
-      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/resources" type="java-test-resource" />
-      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/assets" type="java-test-resource" />
-      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/aidl" isTestSource="true" />
-      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/java" isTestSource="true" />
-      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/rs" isTestSource="true" />
-      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/shaders" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1/res" type="java-test-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1/resources" type="java-test-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1/assets" type="java-test-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1/aidl" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1/jni" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1/rs" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/testFlavor1/shaders" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/res" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/resources" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/assets" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/aidl" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/jni" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/rs" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTestFlavor1/shaders" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/debug/res" type="java-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/debug/resources" type="java-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/debug/assets" type="java-resource" />
@@ -100,6 +102,7 @@
       <sourceFolder url="file://$MODULE_DIR$/src/testDebug/assets" type="java-test-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/testDebug/aidl" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/testDebug/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/testDebug/jni" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/testDebug/rs" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/testDebug/shaders" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/main/res" type="java-resource" />
@@ -109,20 +112,22 @@
       <sourceFolder url="file://$MODULE_DIR$/src/main/java" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/src/main/renderscript" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/src/main/shaders" isTestSource="false" />
-      <sourceFolder url="file://$MODULE_DIR$/src/test/res" type="java-test-resource" />
-      <sourceFolder url="file://$MODULE_DIR$/src/test/resources" type="java-test-resource" />
-      <sourceFolder url="file://$MODULE_DIR$/src/test/assets" type="java-test-resource" />
-      <sourceFolder url="file://$MODULE_DIR$/src/test/aidl" isTestSource="true" />
-      <sourceFolder url="file://$MODULE_DIR$/src/test/java" isTestSource="true" />
-      <sourceFolder url="file://$MODULE_DIR$/src/test/renderscript" isTestSource="true" />
-      <sourceFolder url="file://$MODULE_DIR$/src/test/shaders" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/androidTest/res" type="java-test-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/androidTest/resources" type="java-test-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/androidTest/assets" type="java-test-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/androidTest/aidl" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/androidTest/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/androidTest/jni" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/androidTest/renderscript" isTestSource="true" />
       <sourceFolder url="file://$MODULE_DIR$/src/androidTest/shaders" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/res" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/resources" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/assets" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/aidl" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/java" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/jni" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/renderscript" isTestSource="true" />
+      <sourceFolder url="file://$MODULE_DIR$/src/test/shaders" isTestSource="true" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/assets" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/binaries" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/blame" />
diff --git a/app/build.gradle b/app/build.gradle
index 1b7d3948e..e1f774d86 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -3,7 +3,7 @@ apply plugin: 'com.android.model.application'
 model {
     android {
         compileSdkVersion = 22
-        buildToolsVersion = "23.0.0"
+        buildToolsVersion = "25.0.0"
 
         defaultConfig.with {
             applicationId = "com.android.keepass"
diff --git a/app/src/main/java/com/keepassdroid/crypto/engine/CipherEngine.java b/app/src/main/java/com/keepassdroid/crypto/engine/CipherEngine.java
new file mode 100644
index 000000000..b444d186d
--- /dev/null
+++ b/app/src/main/java/com/keepassdroid/crypto/engine/CipherEngine.java
@@ -0,0 +1,8 @@
+package com.keepassdroid.crypto.engine;
+
+/**
+ * Created by bpellin on 1/29/17.
+ */
+
+public class CipherEngine {
+}
diff --git a/app/src/main/java/com/keepassdroid/stream/HmacBlockStream.java b/app/src/main/java/com/keepassdroid/stream/HmacBlockStream.java
new file mode 100644
index 000000000..ead8e5f05
--- /dev/null
+++ b/app/src/main/java/com/keepassdroid/stream/HmacBlockStream.java
@@ -0,0 +1,55 @@
+/*
+ * Copyright 2017 Brian Pellin.
+ *
+ * This file is part of KeePassDroid.
+ *
+ *  KeePassDroid is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  KeePassDroid is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with KeePassDroid.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+package com.keepassdroid.stream;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.security.DigestOutputStream;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
+public class HmacBlockStream {
+    public static byte[] GetHmacKey64(byte[] key, long blockIndex) {
+        MessageDigest hash;
+        try {
+            hash = MessageDigest.getInstance("SHA-512");
+        } catch (NoSuchAlgorithmException e) {
+            throw new RuntimeException(e);
+        }
+
+        NullOutputStream nos = new NullOutputStream();
+        DigestOutputStream dos = new DigestOutputStream(nos, hash);
+        LEDataOutputStream leos = new LEDataOutputStream(dos);
+
+        try {
+            leos.writeLong(blockIndex);
+            leos.write(key);
+            leos.close();
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+
+        byte[] hashKey = hash.digest();
+        assert(hashKey.length == 64);
+
+        return hashKey;
+    }
+
+}
diff --git a/build.gradle b/build.gradle
index 0aa8572c1..f1cc249cb 100644
--- a/build.gradle
+++ b/build.gradle
@@ -4,7 +4,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle-experimental:0.8.3'
+        classpath 'com.android.tools.build:gradle-experimental:0.9.0'
     }
 }
 
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index e40564412..b3715b1d5 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
-#Mon Oct 24 20:32:21 CDT 2016
+#Sun Mar 26 15:21:55 CDT 2017
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.14.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-3.3-all.zip