bump version

* (optional) disable crazypass generation

* update FAQ about disabling crazypass

.gitignore

@@ -6,4 +6,11 @@
 /captures
 .externalNativeBuild
 .DS_Store
+/app/build
 /app/release
+/app/alpha
+/app/prod
+/app/alphaMainnet
+/app/prodMainnet
+/app/alphaStagenet
+/app/prodStagenet

.idea/gradle.xml

@@ -3,6 +3,7 @@
   <component name="GradleSettings">
     <option name="linkedExternalProjectsSettings">
       <GradleProjectSettings>
+        <option name="disableWrapperSourceDistributionNotification" value="true" />
         <option name="distributionType" value="DEFAULT_WRAPPED" />
         <option name="externalProjectPath" value="$PROJECT_DIR$" />
         <option name="modules">

README.md

@@ -22,12 +22,8 @@ Help us translate Monerujo! You can find instructions [On Taiga](https://taiga.g
 You may lose all your Moneroj if you use this App. Be cautious when spending on the mainnet.
 
 ### Random Notes
-- Based off monero v0.11.1.0
-- currently only android32 (runs on 64-bit as well)
-- works on the testnet & mainnet
-- sync is slow due to 32-bit architecture
+- works on the mainnet & stagenet
 - use your own daemon - it's easy
-- screen stays on until first sync is complete
 - Monerujo means "Monero Wallet" according to https://www.reddit.com/r/Monero/comments/3exy7t/esperanto_corner/
 
 ### TODO
@@ -43,13 +39,8 @@ of the "real" testnet.  After creating a new wallet, make a **new** one by recov
 The official monero client shows the same behaviour.
 
 ### HOW TO BUILD
-No need to build. Binaries are included:
 
-- openssl-1.0.2l
-- monero-v0.12
-- boost_1_58_0
-
-If you want to build them yourself (recommended) check out [the instructions](doc/BUILDING-external-libs.md)
+See [the instructions](doc/BUILDING-external-libs.md)
 
 Then, fire up Android Studio and build the APK.
 

app/.gitignore

@@ -1,3 +0,0 @@
-.externalNativeBuild
-build
-app.iml

app/CMakeLists.txt

@@ -7,13 +7,21 @@ add_library( monerujo
 
 set(EXTERNAL_LIBS_DIR ${CMAKE_SOURCE_DIR}/../external-libs)
 
+############
+# libsodium
+############
+
+add_library(sodium STATIC IMPORTED)
+set_target_properties(sodium PROPERTIES IMPORTED_LOCATION
+        ${EXTERNAL_LIBS_DIR}/libsodium/lib/${ANDROID_ABI}/libsodium.a)
+
 ############
 # OpenSSL
 ############
 
 add_library(crypto STATIC IMPORTED)
 set_target_properties(crypto PROPERTIES IMPORTED_LOCATION
-    ${EXTERNAL_LIBS_DIR}/openssl/lib/${ANDROID_ABI}/libcrypto.a)
+        ${EXTERNAL_LIBS_DIR}/openssl/lib/${ANDROID_ABI}/libcrypto.a)
 
 add_library(ssl STATIC IMPORTED)
 set_target_properties(ssl PROPERTIES IMPORTED_LOCATION
@@ -184,5 +192,7 @@ target_link_libraries(  monerujo
                         ssl
                         crypto
 
+                        sodium
+
                        ${log-lib}
                        )

app/build.gradle

@@ -1,14 +1,15 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 27
-    buildToolsVersion '28.0.2'
+    compileSdkVersion 28
+    buildToolsVersion '28.0.3'
     defaultConfig {
         applicationId "com.m2049r.xmrwallet"
         minSdkVersion 21
-        targetSdkVersion 27
-        versionCode 123
-        versionName "1.7.3 'OpenAlias'"
+        targetSdkVersion 28
+        versionCode 160
+        versionName "1.10.10 'Node-O-matiC'"
+
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
         externalNativeBuild {
             cmake {
@@ -18,6 +19,26 @@ android {
         }
     }
 
+    flavorDimensions 'type', 'net'
+    productFlavors {
+        mainnet {
+            dimension 'net'
+        }
+        stagenet {
+            dimension 'net'
+            applicationIdSuffix '.stage'
+            versionNameSuffix ' (stage)'
+        }
+        alpha {
+            dimension 'type'
+            applicationIdSuffix '.alpha'
+            versionNameSuffix ' (alpha)'
+        }
+        prod {
+            dimension 'type'
+        }
+    }
+
     buildTypes {
         release {
             minifyEnabled false
@@ -27,6 +48,7 @@ android {
             applicationIdSuffix ".debug"
         }
     }
+
     externalNativeBuild {
         cmake {
             path "CMakeLists.txt"
@@ -61,9 +83,13 @@ android {
             output ->
                 def abiName = output.getFilter(com.android.build.OutputFile.ABI)
                 output.versionCodeOverride = abiCodes.get(abiName, 0) + 10 * variant.versionCode
+                //def flavor = output.getFilter(flavor)
 
                 if (abiName == null) abiName = "universal"
-                def v = "${variant.versionName}".replaceFirst(" .*\$", "").replace(".", "x")
+                def v = "${variant.versionName}".replaceFirst(" '.*' ?", "")
+                        .replace(".", "x")
+                        .replace("(", "-")
+                        .replace(")", "")
                 outputFileName = "$rootProject.ext.apkName-" + v + "_" + abiName + ".apk"
         }
     }
@@ -75,9 +101,11 @@ dependencies {
     implementation "com.android.support:support-v4:$rootProject.ext.supportVersion"
     implementation "com.android.support:recyclerview-v7:$rootProject.ext.supportVersion"
     implementation "com.android.support:cardview-v7:$rootProject.ext.supportVersion"
+    implementation "com.android.support:swiperefreshlayout:$rootProject.ext.supportVersion"
     implementation 'me.dm7.barcodescanner:zxing:1.9.8'
 
     implementation "com.squareup.okhttp3:okhttp:$rootProject.ext.okHttpVersion"
+    implementation "com.burgstaller:okhttp-digest:1.18"
     implementation "com.jakewharton.timber:timber:$rootProject.ext.timberVersion"
 
     implementation 'com.nulab-inc:zxcvbn:1.2.3'

app/src/debug/res/values/strings.xml

@@ -1,4 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<resources>
-    <string name="app_name" translatable="false">monerujo - Debug</string>
-</resources>

app/src/main/AndroidManifest.xml

@@ -7,8 +7,10 @@
     <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
     <uses-permission android:name="android.permission.WAKE_LOCK" />
     <uses-permission android:name="android.permission.CAMERA" />
+    <uses-permission android:name="android.permission.USE_BIOMETRIC" />
     <uses-permission android:name="android.permission.USE_FINGERPRINT" />
     <uses-permission android:name="android.permission.NFC" />
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
 
     <application
         android:name=".XmrWalletApplication"
@@ -16,7 +18,8 @@
         android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"
         android:supportsRtl="true"
-        android:theme="@style/MyMaterialTheme">
+        android:theme="@style/MyMaterialTheme"
+        android:usesCleartextTraffic="true">
 
         <activity
             android:name=".WalletActivity"
@@ -43,7 +46,7 @@
                 android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"
                 android:resource="@xml/usb_device_filter" />
         </activity>
-        
+
         <service
             android:name=".service.WalletService"
             android:description="@string/service_description"

app/src/main/cpp/device_io_monerujo.hpp

@@ -0,0 +1,88 @@
+// Copyright (c) 2017-2018, The Monero Project
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+
+#if defined(HAVE_MONERUJO)
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+/**
+ * @brief LedgerFind - find Ledger Device and return it's name
+ * @param buffer     - buffer for name of found device
+ * @param len        - length of buffer
+ * @return  0 - success
+ *         -1 - no device connected / found
+ *         -2 - JVM not found
+ */
+int LedgerFind(char *buffer, size_t len);
+
+/**
+ * @brief LedgerExchange - exchange data with Ledger Device
+ * @param command        - buffer for data to send
+ * @param cmd_len        - length of send to send
+ * @param response       - buffer for received data
+ * @param max_resp_len   - size of receive buffer
+ *
+ * @return length of received data in response or -1 if error
+ */
+int  LedgerExchange(unsigned char *command, unsigned int cmd_len, unsigned char *response, unsigned int max_resp_len);
+
+#ifdef __cplusplus
+}
+#endif
+
+#include "device_io.hpp"
+
+#pragma once
+
+namespace hw {
+  namespace io {
+    class device_io_monerujo: device_io {
+    public:
+      device_io_monerujo() {};
+      ~device_io_monerujo() {};
+
+      void init() {};
+      void release() {};
+
+      void connect(void *params) {};
+      void disconnect() {};
+      bool connected() const {return true;}; // monerujo is always connected before it gets here
+
+      // returns number of bytes read or -1 on error
+      int  exchange(unsigned char *command, unsigned int cmd_len, unsigned char *response, unsigned int max_resp_len) {
+        return LedgerExchange(command, cmd_len, response, max_resp_len);
+      }
+    };
+  };
+};
+
+#endif //#if defined(HAVE_MONERUJO)

app/src/main/cpp/monerujo.cpp

@@ -416,17 +416,20 @@ Java_com_m2049r_xmrwallet_model_WalletManager_verifyWalletPassword(JNIEnv *env,
 
 //virtual int queryWalletHardware(const std::string &keys_file_name, const std::string &password) const = 0;
 JNIEXPORT jint JNICALL
-Java_com_m2049r_xmrwallet_model_WalletManager_queryWalletHardware(JNIEnv *env, jobject instance,
-                                                                  jstring keys_file_name,
-                                                                  jstring password) {
+Java_com_m2049r_xmrwallet_model_WalletManager_queryWalletDeviceJ(JNIEnv *env, jobject instance,
+                                                                 jstring keys_file_name,
+                                                                 jstring password) {
     const char *_keys_file_name = env->GetStringUTFChars(keys_file_name, NULL);
     const char *_password = env->GetStringUTFChars(password, NULL);
-    int hardwareId =
-            Bitmonero::WalletManagerFactory::getWalletManager()->
-                    queryWalletHardware(std::string(_keys_file_name), std::string(_password));
+    Bitmonero::Wallet::Device device_type;
+    bool ok = Bitmonero::WalletManagerFactory::getWalletManager()->
+            queryWalletDevice(device_type, std::string(_keys_file_name), std::string(_password));
     env->ReleaseStringUTFChars(keys_file_name, _keys_file_name);
     env->ReleaseStringUTFChars(password, _password);
-    return static_cast<jint>(hardwareId);
+    if (ok)
+        return static_cast<jint>(device_type);
+    else
+        return -1;
 }
 
 JNIEXPORT jobject JNICALL
@@ -775,16 +778,16 @@ Java_com_m2049r_xmrwallet_model_Wallet_isSynchronized(JNIEnv *env, jobject insta
     return static_cast<jboolean>(wallet->synchronized());
 }
 
-JNIEXPORT jboolean JNICALL
-Java_com_m2049r_xmrwallet_model_Wallet_isKeyOnDevice(JNIEnv *env, jobject instance) {
+JNIEXPORT jint JNICALL
+Java_com_m2049r_xmrwallet_model_Wallet_getDeviceTypeJ(JNIEnv *env, jobject instance) {
     Bitmonero::Wallet *wallet = getHandle<Bitmonero::Wallet>(env, instance);
-    bool key_on_device = wallet->isKeyOnDevice();
-    return static_cast<jboolean>(key_on_device);
+    Bitmonero::Wallet::Device device_type = wallet->getDeviceType();
+    return static_cast<jint>(device_type);
 }
 
 //void cn_slow_hash(const void *data, size_t length, char *hash); // from crypto/hash-ops.h
 JNIEXPORT jbyteArray JNICALL
-Java_com_m2049r_xmrwallet_util_KeyStoreHelper_slowHash(JNIEnv *env, jobject clazz,
+Java_com_m2049r_xmrwallet_util_KeyStoreHelper_slowHash(JNIEnv *env, jclass clazz,
                                                        jbyteArray data, jint brokenVariant) {
     char hash[HASH_SIZE];
     jsize size = env->GetArrayLength(data);
@@ -810,13 +813,13 @@ Java_com_m2049r_xmrwallet_util_KeyStoreHelper_slowHash(JNIEnv *env, jobject claz
 }
 
 JNIEXPORT jstring JNICALL
-Java_com_m2049r_xmrwallet_model_Wallet_getDisplayAmount(JNIEnv *env, jobject clazz,
+Java_com_m2049r_xmrwallet_model_Wallet_getDisplayAmount(JNIEnv *env, jclass clazz,
                                                         jlong amount) {
     return env->NewStringUTF(Bitmonero::Wallet::displayAmount(amount).c_str());
 }
 
 JNIEXPORT jlong JNICALL
-Java_com_m2049r_xmrwallet_model_Wallet_getAmountFromString(JNIEnv *env, jobject clazz,
+Java_com_m2049r_xmrwallet_model_Wallet_getAmountFromString(JNIEnv *env, jclass clazz,
                                                            jstring amount) {
     const char *_amount = env->GetStringUTFChars(amount, NULL);
     uint64_t x = Bitmonero::Wallet::amountFromString(_amount);
@@ -825,18 +828,18 @@ Java_com_m2049r_xmrwallet_model_Wallet_getAmountFromString(JNIEnv *env, jobject
 }
 
 JNIEXPORT jlong JNICALL
-Java_com_m2049r_xmrwallet_model_Wallet_getAmountFromDouble(JNIEnv *env, jobject clazz,
+Java_com_m2049r_xmrwallet_model_Wallet_getAmountFromDouble(JNIEnv *env, jclass clazz,
                                                            jdouble amount) {
     return Bitmonero::Wallet::amountFromDouble(amount);
 }
 
 JNIEXPORT jstring JNICALL
-Java_com_m2049r_xmrwallet_model_Wallet_generatePaymentId(JNIEnv *env, jobject clazz) {
+Java_com_m2049r_xmrwallet_model_Wallet_generatePaymentId(JNIEnv *env, jclass clazz) {
     return env->NewStringUTF(Bitmonero::Wallet::genPaymentId().c_str());
 }
 
 JNIEXPORT jboolean JNICALL
-Java_com_m2049r_xmrwallet_model_Wallet_isPaymentIdValid(JNIEnv *env, jobject clazz,
+Java_com_m2049r_xmrwallet_model_Wallet_isPaymentIdValid(JNIEnv *env, jclass clazz,
                                                         jstring payment_id) {
     const char *_payment_id = env->GetStringUTFChars(payment_id, NULL);
     bool isValid = Bitmonero::Wallet::paymentIdValid(_payment_id);
@@ -845,7 +848,7 @@ Java_com_m2049r_xmrwallet_model_Wallet_isPaymentIdValid(JNIEnv *env, jobject cla
 }
 
 JNIEXPORT jboolean JNICALL
-Java_com_m2049r_xmrwallet_model_Wallet_isAddressValid(JNIEnv *env, jobject clazz,
+Java_com_m2049r_xmrwallet_model_Wallet_isAddressValid(JNIEnv *env, jclass clazz,
                                                       jstring address, jint networkType) {
     const char *_address = env->GetStringUTFChars(address, NULL);
     Monero::NetworkType _networkType = static_cast<Monero::NetworkType>(networkType);
@@ -855,7 +858,7 @@ Java_com_m2049r_xmrwallet_model_Wallet_isAddressValid(JNIEnv *env, jobject clazz
 }
 
 JNIEXPORT jstring JNICALL
-Java_com_m2049r_xmrwallet_model_Wallet_getPaymentIdFromAddress(JNIEnv *env, jobject clazz,
+Java_com_m2049r_xmrwallet_model_Wallet_getPaymentIdFromAddress(JNIEnv *env, jclass clazz,
                                                                jstring address,
                                                                jint networkType) {
     Monero::NetworkType _networkType = static_cast<Monero::NetworkType>(networkType);
@@ -866,7 +869,7 @@ Java_com_m2049r_xmrwallet_model_Wallet_getPaymentIdFromAddress(JNIEnv *env, jobj
 }
 
 JNIEXPORT jlong JNICALL
-Java_com_m2049r_xmrwallet_model_Wallet_getMaximumAllowedAmount(JNIEnv *env, jobject clazz) {
+Java_com_m2049r_xmrwallet_model_Wallet_getMaximumAllowedAmount(JNIEnv *env, jclass clazz) {
     return Bitmonero::Wallet::maximumAllowedAmount();
 }
 
@@ -1182,10 +1185,11 @@ jobject newTransferList(JNIEnv *env, Bitmonero::TransactionInfo *info) {
 
 jobject newTransactionInfo(JNIEnv *env, Bitmonero::TransactionInfo *info) {
     jmethodID c = env->GetMethodID(class_TransactionInfo, "<init>",
-                                   "(IZZJJJLjava/lang/String;JLjava/lang/String;IIJLjava/util/List;)V");
+                                   "(IZZJJJLjava/lang/String;JLjava/lang/String;IIJLjava/lang/String;Ljava/util/List;)V");
     jobject transfers = newTransferList(env, info);
     jstring _hash = env->NewStringUTF(info->hash().c_str());
     jstring _paymentId = env->NewStringUTF(info->paymentId().c_str());
+    jstring _label = env->NewStringUTF(info->label().c_str());
     uint32_t subaddrIndex = 0;
     if (info->direction() == Bitmonero::TransactionInfo::Direction_In)
         subaddrIndex = *(info->subaddrIndex().begin());
@@ -1202,6 +1206,7 @@ jobject newTransactionInfo(JNIEnv *env, Bitmonero::TransactionInfo *info) {
                                     info->subaddrAccount(),
                                     subaddrIndex,
                                     info->confirmations(),
+                                    _label,
                                     transfers);
     env->DeleteLocalRef(transfers);
     env->DeleteLocalRef(_hash);
@@ -1308,7 +1313,7 @@ Java_com_m2049r_xmrwallet_model_PendingTransaction_getTxCount(JNIEnv *env, jobje
 //static void warning(const std::string &category, const std::string &str);
 //static void error(const std::string &category, const std::string &str);
 JNIEXPORT void JNICALL
-Java_com_m2049r_xmrwallet_model_WalletManager_initLogger(JNIEnv *env, jobject instance,
+Java_com_m2049r_xmrwallet_model_WalletManager_initLogger(JNIEnv *env, jclass clazz,
                                                          jstring argv0,
                                                          jstring default_log_base_name) {
 
@@ -1322,7 +1327,7 @@ Java_com_m2049r_xmrwallet_model_WalletManager_initLogger(JNIEnv *env, jobject in
 }
 
 JNIEXPORT void JNICALL
-Java_com_m2049r_xmrwallet_model_WalletManager_logDebug(JNIEnv *env, jobject instance,
+Java_com_m2049r_xmrwallet_model_WalletManager_logDebug(JNIEnv *env, jclass clazz,
                                                        jstring category, jstring message) {
 
     const char *_category = env->GetStringUTFChars(category, NULL);
@@ -1335,7 +1340,7 @@ Java_com_m2049r_xmrwallet_model_WalletManager_logDebug(JNIEnv *env, jobject inst
 }
 
 JNIEXPORT void JNICALL
-Java_com_m2049r_xmrwallet_model_WalletManager_logInfo(JNIEnv *env, jobject instance,
+Java_com_m2049r_xmrwallet_model_WalletManager_logInfo(JNIEnv *env, jclass clazz,
                                                       jstring category, jstring message) {
 
     const char *_category = env->GetStringUTFChars(category, NULL);
@@ -1348,7 +1353,7 @@ Java_com_m2049r_xmrwallet_model_WalletManager_logInfo(JNIEnv *env, jobject insta
 }
 
 JNIEXPORT void JNICALL
-Java_com_m2049r_xmrwallet_model_WalletManager_logWarning(JNIEnv *env, jobject instance,
+Java_com_m2049r_xmrwallet_model_WalletManager_logWarning(JNIEnv *env, jclass clazz,
                                                          jstring category, jstring message) {
 
     const char *_category = env->GetStringUTFChars(category, NULL);
@@ -1361,7 +1366,7 @@ Java_com_m2049r_xmrwallet_model_WalletManager_logWarning(JNIEnv *env, jobject in
 }
 
 JNIEXPORT void JNICALL
-Java_com_m2049r_xmrwallet_model_WalletManager_logError(JNIEnv *env, jobject instance,
+Java_com_m2049r_xmrwallet_model_WalletManager_logError(JNIEnv *env, jclass clazz,
                                                        jstring category, jstring message) {
 
     const char *_category = env->GetStringUTFChars(category, NULL);
@@ -1374,7 +1379,7 @@ Java_com_m2049r_xmrwallet_model_WalletManager_logError(JNIEnv *env, jobject inst
 }
 
 JNIEXPORT void JNICALL
-Java_com_m2049r_xmrwallet_model_WalletManager_setLogLevel(JNIEnv *env, jobject instance,
+Java_com_m2049r_xmrwallet_model_WalletManager_setLogLevel(JNIEnv *env, jclass clazz,
                                                           jint level) {
     Bitmonero::WalletManagerFactory::setLogLevel(level);
 }
@@ -1383,24 +1388,22 @@ Java_com_m2049r_xmrwallet_model_WalletManager_setLogLevel(JNIEnv *env, jobject i
 // Ledger Stuff
 //
 
-#include "monerujo_ledger.h"
+#include "device_io_monerujo.hpp"
 
 /**
  * @brief LedgerExchange - exchange data with Ledger Device
- * @param pbSendBuffer   - buffer for data to send
- * @param cbSendLength   - length of send buffer
- * @param pbRecvBuffer   - buffer for received data
- * @param pcbRecvLength  - pointer to size of receive buffer
- *                         gets set with length of received data on successful return
- * @return SCARD_S_SUCCESS - success
- *         SCARD_E_NO_READERS_AVAILABLE - no device connected / found
- *         SCARD_E_INSUFFICIENT_BUFFER  - pbRecvBuffer is too small for the response
+ * @param command        - buffer for data to send
+ * @param cmd_len        - length of send to send
+ * @param response       - buffer for received data
+ * @param max_resp_len   - size of receive buffer
+ *
+ * @return length of received data in response or -1 if error
  */
-LONG LedgerExchange(
-        LPCBYTE pbSendBuffer,
-        DWORD cbSendLength,
-        LPBYTE pbRecvBuffer,
-        LPDWORD pcbRecvLength) {
+int LedgerExchange(
+        unsigned char *command,
+        unsigned int cmd_len,
+        unsigned char *response,
+        unsigned int max_resp_len) {
     LOGD("LedgerExchange");
     JNIEnv *jenv;
     int envStat = attachJVM(&jenv);
@@ -1408,30 +1411,29 @@ LONG LedgerExchange(
 
     jmethodID exchangeMethod = jenv->GetStaticMethodID(class_Ledger, "Exchange", "([B)[B");
 
-    jsize sendLen = static_cast<jsize>(cbSendLength);
+    jsize sendLen = static_cast<jsize>(cmd_len);
     jbyteArray dataSend = jenv->NewByteArray(sendLen);
-    jenv->SetByteArrayRegion(dataSend, 0, sendLen, (jbyte *) pbSendBuffer);
+    jenv->SetByteArrayRegion(dataSend, 0, sendLen, (jbyte *) command);
     jbyteArray dataRecv = (jbyteArray) jenv->CallStaticObjectMethod(class_Ledger, exchangeMethod,
                                                                     dataSend);
     jenv->DeleteLocalRef(dataSend);
     if (dataRecv == nullptr) {
         detachJVM(jenv, envStat);
         LOGD("LedgerExchange SCARD_E_NO_READERS_AVAILABLE");
-        return SCARD_E_NO_READERS_AVAILABLE;
+        return -1;
     }
     jsize len = jenv->GetArrayLength(dataRecv);
-    LOGD("LedgerExchange SCARD_S_SUCCESS %ld/%d", cbSendLength, len);
-    if (len <= *pcbRecvLength) {
-        *pcbRecvLength = static_cast<DWORD>(len);
-        jenv->GetByteArrayRegion(dataRecv, 0, len, (jbyte *) pbRecvBuffer);
+    LOGD("LedgerExchange SCARD_S_SUCCESS %ld/%d", cmd_len, len);
+    if (len <= max_resp_len) {
+        jenv->GetByteArrayRegion(dataRecv, 0, len, (jbyte *) response);
         jenv->DeleteLocalRef(dataRecv);
         detachJVM(jenv, envStat);
-        return SCARD_S_SUCCESS;
+        return static_cast<int>(len);;
     } else {
         jenv->DeleteLocalRef(dataRecv);
         detachJVM(jenv, envStat);
         LOGE("LedgerExchange SCARD_E_INSUFFICIENT_BUFFER");
-        return SCARD_E_INSUFFICIENT_BUFFER;
+        return -1;
     }
 }
 

app/src/main/cpp/monerujo_ledger.h

@@ -1,46 +0,0 @@
-/**
- * Copyright (c) 2018 m2049r
- * <p>
- * 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
- * <p>
- * http://www.apache.org/licenses/LICENSE-2.0
- * <p>
- * 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 XMRWALLET_LEDGER_H
-#define XMRWALLET_LEDGER_H
-
-#ifdef __cplusplus
-extern "C"
-{
-#endif
-
-#define SCARD_S_SUCCESS ((LONG)0x00000000) /**< No error was encountered. */
-#define SCARD_E_INSUFFICIENT_BUFFER    ((LONG)0x80100008) /**< The data buffer to receive returned data is too small for the returned data. */
-#define SCARD_E_NO_READERS_AVAILABLE ((LONG)0x8010002E) /**< Cannot find a smart card reader. */
-
-typedef long LONG;
-typedef unsigned long DWORD;
-typedef DWORD *LPDWORD;
-typedef unsigned char BYTE;
-typedef BYTE *LPBYTE;
-typedef const BYTE *LPCBYTE;
-
-typedef char CHAR;
-typedef CHAR *LPSTR;
-
-int LedgerFind(char *buffer, size_t len);
-LONG LedgerExchange(LPCBYTE pbSendBuffer, DWORD cbSendLength, LPBYTE pbRecvBuffer, LPDWORD pcbRecvLength);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif //XMRWALLET_LEDGER_H

app/src/main/java/com/btchip/comm/BTChipTransport.java

@@ -23,9 +23,9 @@ package com.btchip.comm;
 import com.btchip.BTChipException;
 
 public interface BTChipTransport {
-    public byte[] exchange(byte[] command);
+    byte[] exchange(byte[] command);
 
-    public void close();
+    void close();
 
-    public void setDebug(boolean debugFlag);
+    void setDebug(boolean debugFlag);
 }

app/src/main/java/com/m2049r/levin/data/Bucket.java

@@ -0,0 +1,145 @@
+/*
+ * Copyright (c) 2018 m2049r
+ *
+ * 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 com.m2049r.levin.data;
+
+import com.m2049r.levin.util.HexHelper;
+import com.m2049r.levin.util.LevinReader;
+
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.io.IOException;
+
+public class Bucket {
+
+    // constants copied from monero p2p & epee
+
+    public final static int P2P_COMMANDS_POOL_BASE = 1000;
+    public final static int COMMAND_HANDSHAKE_ID = P2P_COMMANDS_POOL_BASE + 1;
+    public final static int COMMAND_TIMED_SYNC_ID = P2P_COMMANDS_POOL_BASE + 2;
+    public final static int COMMAND_PING_ID = P2P_COMMANDS_POOL_BASE + 3;
+    public final static int COMMAND_REQUEST_STAT_INFO_ID = P2P_COMMANDS_POOL_BASE + 4;
+    public final static int COMMAND_REQUEST_NETWORK_STATE_ID = P2P_COMMANDS_POOL_BASE + 5;
+    public final static int COMMAND_REQUEST_PEER_ID_ID = P2P_COMMANDS_POOL_BASE + 6;
+    public final static int COMMAND_REQUEST_SUPPORT_FLAGS_ID = P2P_COMMANDS_POOL_BASE + 7;
+
+    public final static long LEVIN_SIGNATURE = 0x0101010101012101L; // Bender's nightmare
+
+    public final static long LEVIN_DEFAULT_MAX_PACKET_SIZE = 100000000; // 100MB by default
+
+    public final static int LEVIN_PACKET_REQUEST = 0x00000001;
+    public final static int LEVIN_PACKET_RESPONSE = 0x00000002;
+
+    public final static int LEVIN_PROTOCOL_VER_0 = 0;
+    public final static int LEVIN_PROTOCOL_VER_1 = 1;
+
+    public final static int LEVIN_OK = 0;
+    public final static int LEVIN_ERROR_CONNECTION = -1;
+    public final static int LEVIN_ERROR_CONNECTION_NOT_FOUND = -2;
+    public final static int LEVIN_ERROR_CONNECTION_DESTROYED = -3;
+    public final static int LEVIN_ERROR_CONNECTION_TIMEDOUT = -4;
+    public final static int LEVIN_ERROR_CONNECTION_NO_DUPLEX_PROTOCOL = -5;
+    public final static int LEVIN_ERROR_CONNECTION_HANDLER_NOT_DEFINED = -6;
+    public final static int LEVIN_ERROR_FORMAT = -7;
+
+    public final static int P2P_SUPPORT_FLAG_FLUFFY_BLOCKS = 0x01;
+    public final static int P2P_SUPPORT_FLAGS = P2P_SUPPORT_FLAG_FLUFFY_BLOCKS;
+
+    final private long signature;
+    final private long cb;
+    final public boolean haveToReturnData;
+    final public int command;
+    final public int returnCode;
+    final private int flags;
+    final private int protcolVersion;
+    final byte[] payload;
+
+    final public Section payloadSection;
+
+    // create a request
+    public Bucket(int command, byte[] payload) throws IOException {
+        this.signature = LEVIN_SIGNATURE;
+        this.cb = payload.length;
+        this.haveToReturnData = true;
+        this.command = command;
+        this.returnCode = 0;
+        this.flags = LEVIN_PACKET_REQUEST;
+        this.protcolVersion = LEVIN_PROTOCOL_VER_1;
+        this.payload = payload;
+        payloadSection = LevinReader.readPayload(payload);
+    }
+
+    // create a response
+    public Bucket(int command, byte[] payload, int rc) throws IOException {
+        this.signature = LEVIN_SIGNATURE;
+        this.cb = payload.length;
+        this.haveToReturnData = false;
+        this.command = command;
+        this.returnCode = rc;
+        this.flags = LEVIN_PACKET_RESPONSE;
+        this.protcolVersion = LEVIN_PROTOCOL_VER_1;
+        this.payload = payload;
+        payloadSection = LevinReader.readPayload(payload);
+    }
+
+    public Bucket(DataInput in) throws IOException {
+        signature = in.readLong();
+        cb = in.readLong();
+        haveToReturnData = in.readBoolean();
+        command = in.readInt();
+        returnCode = in.readInt();
+        flags = in.readInt();
+        protcolVersion = in.readInt();
+
+        if (signature == Bucket.LEVIN_SIGNATURE) {
+            if (cb > Integer.MAX_VALUE)
+                throw new IllegalArgumentException();
+            payload = new byte[(int) cb];
+            in.readFully(payload);
+        } else
+            throw new IllegalStateException();
+        payloadSection = LevinReader.readPayload(payload);
+    }
+
+    public Section getPayloadSection() {
+        return payloadSection;
+    }
+
+    public void send(DataOutput out) throws IOException {
+        out.writeLong(signature);
+        out.writeLong(cb);
+        out.writeBoolean(haveToReturnData);
+        out.writeInt(command);
+        out.writeInt(returnCode);
+        out.writeInt(flags);
+        out.writeInt(protcolVersion);
+        out.write(payload);
+    }
+
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append("sig:  ").append(signature).append("\n");
+        sb.append("cb:   ").append(cb).append("\n");
+        sb.append("call: ").append(haveToReturnData).append("\n");
+        sb.append("cmd:  ").append(command).append("\n");
+        sb.append("rc:   ").append(returnCode).append("\n");
+        sb.append("flags:").append(flags).append("\n");
+        sb.append("proto:").append(protcolVersion).append("\n");
+        sb.append(HexHelper.bytesToHex(payload)).append("\n");
+        sb.append(payloadSection.toString());
+        return sb.toString();
+    }
+}

app/src/main/java/com/m2049r/levin/data/Section.java

@@ -0,0 +1,125 @@
+/*
+ * Copyright (c) 2018 m2049r
+ *
+ * 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 com.m2049r.levin.data;
+
+import com.m2049r.levin.util.HexHelper;
+import com.m2049r.levin.util.LevinReader;
+import com.m2049r.levin.util.LevinWriter;
+import com.m2049r.levin.util.LittleEndianDataOutputStream;
+
+import java.io.ByteArrayOutputStream;
+import java.io.DataOutput;
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+public class Section {
+
+    // constants copied from monero p2p & epee
+
+    static final public int PORTABLE_STORAGE_SIGNATUREA = 0x01011101;
+    static final public int PORTABLE_STORAGE_SIGNATUREB = 0x01020101;
+
+    static final public byte PORTABLE_STORAGE_FORMAT_VER = 1;
+
+    static final public byte PORTABLE_RAW_SIZE_MARK_MASK = 0x03;
+    static final public byte PORTABLE_RAW_SIZE_MARK_BYTE = 0;
+    static final public byte PORTABLE_RAW_SIZE_MARK_WORD = 1;
+    static final public byte PORTABLE_RAW_SIZE_MARK_DWORD = 2;
+    static final public byte PORTABLE_RAW_SIZE_MARK_INT64 = 3;
+
+    static final long MAX_STRING_LEN_POSSIBLE = 2000000000; // do not let string be so big
+
+    // data types
+    static final public byte SERIALIZE_TYPE_INT64 = 1;
+    static final public byte SERIALIZE_TYPE_INT32 = 2;
+    static final public byte SERIALIZE_TYPE_INT16 = 3;
+    static final public byte SERIALIZE_TYPE_INT8 = 4;
+    static final public byte SERIALIZE_TYPE_UINT64 = 5;
+    static final public byte SERIALIZE_TYPE_UINT32 = 6;
+    static final public byte SERIALIZE_TYPE_UINT16 = 7;
+    static final public byte SERIALIZE_TYPE_UINT8 = 8;
+    static final public byte SERIALIZE_TYPE_DUOBLE = 9;
+    static final public byte SERIALIZE_TYPE_STRING = 10;
+    static final public byte SERIALIZE_TYPE_BOOL = 11;
+    static final public byte SERIALIZE_TYPE_OBJECT = 12;
+    static final public byte SERIALIZE_TYPE_ARRAY = 13;
+
+    static final public byte SERIALIZE_FLAG_ARRAY = (byte) 0x80;
+
+    private final Map<String, Object> entries = new HashMap<String, Object>();
+
+    public void add(String key, Object entry) {
+        entries.put(key, entry);
+    }
+
+    public int size() {
+        return entries.size();
+    }
+
+    public Set<Map.Entry<String, Object>> entrySet() {
+        return entries.entrySet();
+    }
+
+    public Object get(String key) {
+        return entries.get(key);
+    }
+
+    public String toString() {
+        final StringBuilder sb = new StringBuilder();
+        sb.append("\n");
+        for (Map.Entry<String, Object> entry : entries.entrySet()) {
+            sb.append(entry.getKey()).append("=");
+            final Object value = entry.getValue();
+            if (value instanceof List) {
+                @SuppressWarnings("unchecked") final List<Object> list = (List<Object>) value;
+                for (Object listEntry : list) {
+                    sb.append(listEntry.toString()).append("\n");
+                }
+            } else if (value instanceof String) {
+                sb.append("(").append(value).append(")\n");
+            } else if (value instanceof byte[]) {
+                sb.append(HexHelper.bytesToHex((byte[]) value)).append("\n");
+            } else {
+                sb.append(value.toString()).append("\n");
+            }
+        }
+        return sb.toString();
+    }
+
+    static public Section fromByteArray(byte[] buffer) {
+        try {
+            return LevinReader.readPayload(buffer);
+        } catch (IOException ex) {
+            throw new IllegalStateException();
+        }
+    }
+
+    public byte[] asByteArray() {
+        try {
+            ByteArrayOutputStream bas = new ByteArrayOutputStream();
+            DataOutput out = new LittleEndianDataOutputStream(bas);
+            LevinWriter writer = new LevinWriter(out);
+            writer.writePayload(this);
+            return bas.toByteArray();
+        } catch (IOException ex) {
+            throw new IllegalStateException();
+        }
+    }
+}

app/src/main/java/com/m2049r/levin/scanner/Dispatcher.java

@@ -0,0 +1,197 @@
+/*
+ * Copyright (c) 2018 m2049r
+ *
+ * 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 com.m2049r.levin.scanner;
+
+import com.m2049r.xmrwallet.data.NodeInfo;
+
+import java.net.InetSocketAddress;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Set;
+import java.util.TreeMap;
+import java.util.concurrent.ConcurrentLinkedDeque;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.TimeUnit;
+
+import timber.log.Timber;
+
+public class Dispatcher implements PeerRetriever.OnGetPeers {
+    static final public int NUM_THREADS = 50;
+    static final public int MAX_PEERS = 1000;
+    static final public long MAX_TIME = 30000000000L; //30 seconds
+
+    private int peerCount = 0;
+    final private Set<NodeInfo> knownNodes = new HashSet<>(); // set of nodes to test
+    final private Set<NodeInfo> rpcNodes = new HashSet<>(); // set of RPC nodes we like
+    final private ExecutorService exeService = Executors.newFixedThreadPool(NUM_THREADS);
+
+    public interface Listener {
+        void onGet(NodeInfo nodeInfo);
+    }
+
+    private Listener listener;
+
+    public Dispatcher(Listener listener) {
+        this.listener = listener;
+    }
+
+    public Set<NodeInfo> getRpcNodes() {
+        return rpcNodes;
+    }
+
+    public int getPeerCount() {
+        return peerCount;
+    }
+
+    public boolean getMorePeers() {
+        return peerCount < MAX_PEERS;
+    }
+
+    public void awaitTermination(int nodesToFind) {
+        try {
+            final long t = System.nanoTime();
+            while (!jobs.isEmpty()) {
+                try {
+                    Timber.d("Remaining jobs %d", jobs.size());
+                    final PeerRetriever retrievedPeer = jobs.poll().get();
+                    if (retrievedPeer.isGood() && getMorePeers())
+                        retrievePeers(retrievedPeer);
+                    final NodeInfo nodeInfo = retrievedPeer.getNodeInfo();
+                    Timber.d("Retrieved %s", nodeInfo);
+                    if ((nodeInfo.isValid() || nodeInfo.isFavourite())) {
+                        nodeInfo.setName();
+                        rpcNodes.add(nodeInfo);
+                        Timber.d("RPC: %s", nodeInfo);
+                        // the following is not totally correct but it works (otherwise we need to
+                        // load much more before filtering - but we don't have time
+                        if (listener != null) listener.onGet(nodeInfo);
+                        if (rpcNodes.size() >= nodesToFind) {
+                            Timber.d("are we done here?");
+                            filterRpcNodes();
+                            if (rpcNodes.size() >= nodesToFind) {
+                                Timber.d("we're done here");
+                                break;
+                            }
+                        }
+                    }
+                    if (System.nanoTime() - t > MAX_TIME) break; // watchdog
+                } catch (ExecutionException ex) {
+                    Timber.d(ex); // tell us about it and continue
+                }
+            }
+        } catch (InterruptedException ex) {
+            Timber.d(ex);
+        } finally {
+            Timber.d("Shutting down!");
+            exeService.shutdownNow();
+            try {
+                exeService.awaitTermination(Long.MAX_VALUE, TimeUnit.DAYS);
+            } catch (InterruptedException ex) {
+                Timber.d(ex);
+            }
+        }
+        filterRpcNodes();
+    }
+
+    static final public int HEIGHT_WINDOW = 1;
+
+    private boolean testHeight(long height, long consensus) {
+        return (height >= (consensus - HEIGHT_WINDOW))
+                && (height <= (consensus + HEIGHT_WINDOW));
+    }
+
+    private long calcConsensusHeight() {
+        Timber.d("Calc Consensus height from %d nodes", rpcNodes.size());
+        final Map<Long, Integer> nodeHeights = new TreeMap<Long, Integer>();
+        for (NodeInfo info : rpcNodes) {
+            if (!info.isValid()) continue;
+            Integer h = nodeHeights.get(info.getHeight());
+            if (h == null)
+                h = 0;
+            nodeHeights.put(info.getHeight(), h + 1);
+        }
+        long consensusHeight = 0;
+        long consensusCount = 0;
+        for (Map.Entry<Long, Integer> entry : nodeHeights.entrySet()) {
+            final long entryHeight = entry.getKey();
+            int count = 0;
+            for (long i = entryHeight - HEIGHT_WINDOW; i <= entryHeight + HEIGHT_WINDOW; i++) {
+                Integer v = nodeHeights.get(i);
+                if (v == null)
+                    v = 0;
+                count += v;
+            }
+            if (count >= consensusCount) {
+                consensusCount = count;
+                consensusHeight = entryHeight;
+            }
+            Timber.d("%d - %d/%d", entryHeight, count, entry.getValue());
+        }
+        return consensusHeight;
+    }
+
+    private void filterRpcNodes() {
+        long consensus = calcConsensusHeight();
+        Timber.d("Consensus Height = %d for %d nodes", consensus, rpcNodes.size());
+        for (Iterator<NodeInfo> iter = rpcNodes.iterator(); iter.hasNext(); ) {
+            NodeInfo info = iter.next();
+            // don't remove favourites
+            if (!info.isFavourite()) {
+                if (!testHeight(info.getHeight(), consensus)) {
+                    iter.remove();
+                    Timber.d("Removed %s", info);
+                }
+            }
+        }
+    }
+
+    // TODO: does this NEED to be a ConcurrentLinkedDeque?
+    private ConcurrentLinkedDeque<Future<PeerRetriever>> jobs = new ConcurrentLinkedDeque<>();
+
+    private void retrievePeer(NodeInfo nodeInfo) {
+        if (knownNodes.add(nodeInfo)) {
+            Timber.d("\t%d:%s", knownNodes.size(), nodeInfo);
+            jobs.add(exeService.submit(new PeerRetriever(nodeInfo, this)));
+            peerCount++; // jobs.size() does not perform well
+        }
+    }
+
+    private void retrievePeers(PeerRetriever peer) {
+        for (InetSocketAddress socketAddress : peer.getPeers()) {
+            if (getMorePeers())
+                retrievePeer(new NodeInfo(socketAddress));
+            else
+                break;
+        }
+    }
+
+    public void seedPeers(Collection<NodeInfo> seedNodes) {
+        for (NodeInfo node : seedNodes) {
+            node.clear();
+            if (node.isFavourite()) {
+                rpcNodes.add(node);
+                if (listener != null) listener.onGet(node);
+            }
+            retrievePeer(node);
+        }
+    }
+}

app/src/main/java/com/m2049r/levin/scanner/PeerRetriever.java

@@ -0,0 +1,226 @@
+/*
+ * Copyright (c) 2018 m2049r
+ *
+ * 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 com.m2049r.levin.scanner;
+
+import com.m2049r.levin.data.Bucket;
+import com.m2049r.levin.data.Section;
+import com.m2049r.levin.util.HexHelper;
+import com.m2049r.levin.util.LittleEndianDataInputStream;
+import com.m2049r.levin.util.LittleEndianDataOutputStream;
+import com.m2049r.xmrwallet.data.NodeInfo;
+import com.m2049r.xmrwallet.util.Helper;
+
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.io.IOException;
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.Socket;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+import java.util.Random;
+import java.util.concurrent.Callable;
+
+import timber.log.Timber;
+
+public class PeerRetriever implements Callable<PeerRetriever> {
+    static final public int CONNECT_TIMEOUT = 500; //ms
+    static final public int SOCKET_TIMEOUT = 500; //ms
+    static final public long PEER_ID = new Random().nextLong();
+    static final private byte[] HANDSHAKE = handshakeRequest().asByteArray();
+    static final private byte[] FLAGS_RESP = flagsResponse().asByteArray();
+
+    final private List<InetSocketAddress> peers = new ArrayList<>();
+
+    private NodeInfo nodeInfo;
+    private OnGetPeers onGetPeersCallback;
+
+    public interface OnGetPeers {
+        boolean getMorePeers();
+    }
+
+    public PeerRetriever(NodeInfo nodeInfo, OnGetPeers onGetPeers) {
+        this.nodeInfo = nodeInfo;
+        this.onGetPeersCallback = onGetPeers;
+    }
+
+    public NodeInfo getNodeInfo() {
+        return nodeInfo;
+    }
+
+    public boolean isGood() {
+        return !peers.isEmpty();
+    }
+
+    public List<InetSocketAddress> getPeers() {
+        return peers;
+    }
+
+    public PeerRetriever call() {
+        if (isGood()) // we have already been called?
+            throw new IllegalStateException();
+        // first check for an rpc service
+        nodeInfo.findRpcService();
+        if (onGetPeersCallback.getMorePeers())
+            try {
+                Timber.d("%s CONN", nodeInfo.getLevinSocketAddress());
+                if (!connect())
+                    return this;
+                Bucket handshakeBucket = new Bucket(Bucket.COMMAND_HANDSHAKE_ID, HANDSHAKE);
+                handshakeBucket.send(getDataOutput());
+
+                while (true) {// wait for response (which may never come)
+                    Bucket recv = new Bucket(getDataInput()); // times out after SOCKET_TIMEOUT
+                    if ((recv.command == Bucket.COMMAND_HANDSHAKE_ID)
+                            && (!recv.haveToReturnData)) {
+                        readAddressList(recv.payloadSection);
+                        return this;
+                    } else if ((recv.command == Bucket.COMMAND_REQUEST_SUPPORT_FLAGS_ID)
+                            && (recv.haveToReturnData)) {
+                        Bucket flagsBucket = new Bucket(Bucket.COMMAND_REQUEST_SUPPORT_FLAGS_ID, FLAGS_RESP, 1);
+                        flagsBucket.send(getDataOutput());
+                    } else {// and ignore others
+                        Timber.d("Ignored LEVIN COMMAND %d", recv.command);
+                    }
+                }
+            } catch (IOException ex) {
+            } finally {
+                disconnect(); // we have what we want - byebye
+                Timber.d("%s DISCONN", nodeInfo.getLevinSocketAddress());
+            }
+        return this;
+    }
+
+    private void readAddressList(Section section) {
+        @SuppressWarnings("unchecked")
+        List<Section> peerList = (List<Section>) section.get("local_peerlist_new");
+        if (peerList != null) {
+            for (Section peer : peerList) {
+                Section adr = (Section) peer.get("adr");
+                Byte type = (Byte) adr.get("type");
+                if ((type == null) || (type != 1))
+                    continue;
+                Section addr = (Section) adr.get("addr");
+                if (addr == null)
+                    continue;
+                Integer ip = (Integer) addr.get("m_ip");
+                if (ip == null)
+                    continue;
+                Short sport = (Short) addr.get("m_port");
+                if (sport == null)
+                    continue;
+                int port = sport;
+                if (port < 0) // port is unsigned
+                    port = port + 0x10000;
+                InetAddress inet = HexHelper.toInetAddress(ip);
+                // make sure this is an address we want to talk to (i.e. a remote address)
+                if (!inet.isSiteLocalAddress() && !inet.isAnyLocalAddress()
+                        && !inet.isLoopbackAddress()
+                        && !inet.isMulticastAddress()
+                        && !inet.isLinkLocalAddress()) {
+                    peers.add(new InetSocketAddress(inet, port));
+                }
+            }
+        }
+    }
+
+    private Socket socket = null;
+
+    private boolean connect() {
+        if (socket != null) throw new IllegalStateException();
+        try {
+            socket = new Socket();
+            socket.connect(nodeInfo.getLevinSocketAddress(), CONNECT_TIMEOUT);
+            socket.setSoTimeout(SOCKET_TIMEOUT);
+        } catch (IOException ex) {
+            //Timber.d(ex);
+            return false;
+        }
+        return true;
+    }
+
+    private boolean isConnected() {
+        return socket.isConnected();
+    }
+
+    private void disconnect() {
+        try {
+            dataInput = null;
+            dataOutput = null;
+            if ((socket != null) && (!socket.isClosed())) {
+                socket.close();
+            }
+        } catch (IOException ex) {
+            Timber.d(ex);
+        } finally {
+            socket = null;
+        }
+    }
+
+    private DataOutput dataOutput = null;
+
+    private DataOutput getDataOutput() throws IOException {
+        if (dataOutput == null)
+            synchronized (this) {
+                if (dataOutput == null)
+                    dataOutput = new LittleEndianDataOutputStream(
+                            socket.getOutputStream());
+            }
+        return dataOutput;
+    }
+
+    private DataInput dataInput = null;
+
+    private DataInput getDataInput() throws IOException {
+        if (dataInput == null)
+            synchronized (this) {
+                if (dataInput == null)
+                    dataInput = new LittleEndianDataInputStream(
+                            socket.getInputStream());
+            }
+        return dataInput;
+    }
+
+    static private Section handshakeRequest() {
+        Section section = new Section(); // root object
+
+        Section nodeData = new Section();
+        nodeData.add("local_time", (new Date()).getTime());
+        nodeData.add("my_port", 0);
+        byte[] networkId = Helper.hexToBytes("1230f171610441611731008216a1a110"); // mainnet
+        nodeData.add("network_id", networkId);
+        nodeData.add("peer_id", PEER_ID);
+        section.add("node_data", nodeData);
+
+        Section payloadData = new Section();
+        payloadData.add("cumulative_difficulty", 1L);
+        payloadData.add("current_height", 1L);
+        byte[] genesisHash =
+                Helper.hexToBytes("418015bb9ae982a1975da7d79277c2705727a56894ba0fb246adaabb1f4632e3");
+        payloadData.add("top_id", genesisHash);
+        payloadData.add("top_version", (byte) 1);
+        section.add("payload_data", payloadData);
+        return section;
+    }
+
+    static private Section flagsResponse() {
+        Section section = new Section(); // root object
+        section.add("support_flags", Bucket.P2P_SUPPORT_FLAGS);
+        return section;
+    }
+}

app/src/main/java/com/m2049r/levin/util/HexHelper.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2018 m2049r
+ *
+ * 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 com.m2049r.levin.util;
+
+import java.math.BigInteger;
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
+public class HexHelper {
+
+    static public String bytesToHex(byte[] data) {
+        if ((data != null) && (data.length > 0))
+            return String.format("%0" + (data.length * 2) + "X",
+                    new BigInteger(1, data));
+        else
+            return "";
+    }
+
+    static public InetAddress toInetAddress(int ip) {
+        try {
+            String ipAddress = String.format("%d.%d.%d.%d", (ip & 0xff),
+                    (ip >> 8 & 0xff), (ip >> 16 & 0xff), (ip >> 24 & 0xff));
+            return InetAddress.getByName(ipAddress);
+        } catch (UnknownHostException ex) {
+            throw new IllegalArgumentException(ex);
+        }
+    }
+}

app/src/main/java/com/m2049r/levin/util/LevinReader.java

@@ -0,0 +1,182 @@
+/*
+ * Copyright (c) 2018 m2049r
+ *
+ * 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 com.m2049r.levin.util;
+
+import com.m2049r.levin.data.Section;
+
+import java.io.ByteArrayInputStream;
+import java.io.DataInput;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
+import java.util.List;
+
+// Full Levin reader as seen on epee
+
+public class LevinReader {
+    private DataInput in;
+
+    private LevinReader(byte[] buffer) {
+        ByteArrayInputStream bis = new ByteArrayInputStream(buffer);
+        in = new LittleEndianDataInputStream(bis);
+    }
+
+    static public Section readPayload(byte[] payload) throws IOException {
+        LevinReader r = new LevinReader(payload);
+        return r.readPayload();
+    }
+
+    private Section readPayload() throws IOException {
+        if (in.readInt() != Section.PORTABLE_STORAGE_SIGNATUREA)
+            throw new IllegalStateException();
+        if (in.readInt() != Section.PORTABLE_STORAGE_SIGNATUREB)
+            throw new IllegalStateException();
+        if (in.readByte() != Section.PORTABLE_STORAGE_FORMAT_VER)
+            throw new IllegalStateException();
+        return readSection();
+    }
+
+    private Section readSection() throws IOException {
+        Section section = new Section();
+        long count = readVarint();
+        while (count-- > 0) {
+            // read section name string
+            String sectionName = readSectionName();
+            section.add(sectionName, loadStorageEntry());
+        }
+        return section;
+    }
+
+    private Object loadStorageArrayEntry(int type) throws IOException {
+        type &= ~Section.SERIALIZE_FLAG_ARRAY;
+        return readArrayEntry(type);
+    }
+
+    private List<Object> readArrayEntry(int type) throws IOException {
+        List<Object> list = new ArrayList<Object>();
+        long size = readVarint();
+        while (size-- > 0)
+            list.add(read(type));
+        return list;
+    }
+
+    private Object read(int type) throws IOException {
+        switch (type) {
+            case Section.SERIALIZE_TYPE_UINT64:
+            case Section.SERIALIZE_TYPE_INT64:
+                return in.readLong();
+            case Section.SERIALIZE_TYPE_UINT32:
+            case Section.SERIALIZE_TYPE_INT32:
+                return in.readInt();
+            case Section.SERIALIZE_TYPE_UINT16:
+            case Section.SERIALIZE_TYPE_INT16:
+                return in.readShort();
+            case Section.SERIALIZE_TYPE_UINT8:
+            case Section.SERIALIZE_TYPE_INT8:
+                return in.readByte();
+            case Section.SERIALIZE_TYPE_OBJECT:
+                return readSection();
+            case Section.SERIALIZE_TYPE_STRING:
+                return readByteArray();
+            default:
+                throw new IllegalArgumentException("type " + type
+                        + " not supported");
+        }
+    }
+
+    private Object loadStorageEntry() throws IOException {
+        int type = in.readUnsignedByte();
+        if ((type & Section.SERIALIZE_FLAG_ARRAY) != 0)
+            return loadStorageArrayEntry(type);
+        if (type == Section.SERIALIZE_TYPE_ARRAY)
+            return readStorageEntryArrayEntry();
+        else
+            return readStorageEntry(type);
+    }
+
+    private Object readStorageEntry(int type) throws IOException {
+        return read(type);
+    }
+
+    private Object readStorageEntryArrayEntry() throws IOException {
+        int type = in.readUnsignedByte();
+        if ((type & Section.SERIALIZE_FLAG_ARRAY) != 0)
+            throw new IllegalStateException("wrong type sequences");
+        return loadStorageArrayEntry(type);
+    }
+
+    private String readSectionName() throws IOException {
+        int nameLen = in.readUnsignedByte();
+        return readString(nameLen);
+    }
+
+    private byte[] read(long count) throws IOException {
+        if (count > Integer.MAX_VALUE)
+            throw new IllegalArgumentException();
+        int len = (int) count;
+        final byte buffer[] = new byte[len];
+        in.readFully(buffer);
+        return buffer;
+    }
+
+    private String readString(long count) throws IOException {
+        return new String(read(count), StandardCharsets.US_ASCII);
+    }
+
+    private byte[] readByteArray(long count) throws IOException {
+        return read(count);
+    }
+
+    private byte[] readByteArray() throws IOException {
+        long len = readVarint();
+        return readByteArray(len);
+    }
+
+    private long readVarint() throws IOException {
+        long v = 0;
+        int b = in.readUnsignedByte();
+        int sizeMask = b & Section.PORTABLE_RAW_SIZE_MARK_MASK;
+        switch (sizeMask) {
+            case Section.PORTABLE_RAW_SIZE_MARK_BYTE:
+                v = b >>> 2;
+                break;
+            case Section.PORTABLE_RAW_SIZE_MARK_WORD:
+                v = readRest(b, 1) >>> 2;
+                break;
+            case Section.PORTABLE_RAW_SIZE_MARK_DWORD:
+                v = readRest(b, 3) >>> 2;
+                break;
+            case Section.PORTABLE_RAW_SIZE_MARK_INT64:
+                v = readRest(b, 7) >>> 2;
+                break;
+            default:
+                throw new IllegalStateException();
+        }
+        return v;
+    }
+
+    // this should be in LittleEndianDataInputStream because it has little
+    // endian logic
+    private long readRest(int firstByte, int bytes) throws IOException {
+        long result = firstByte;
+        for (int i = 0; i < bytes; i++) {
+            result = result + (in.readUnsignedByte() << 8);
+        }
+        return result;
+    }
+
+}

app/src/main/java/com/m2049r/levin/util/LevinWriter.java

@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2018 m2049r
+ *
+ * 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 com.m2049r.levin.util;
+
+import com.m2049r.levin.data.Section;
+
+import java.io.DataOutput;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.util.Map;
+
+// a simplified Levin Writer WITHOUT support for arrays
+
+public class LevinWriter {
+    private DataOutput out;
+
+    public LevinWriter(DataOutput out) {
+        this.out = out;
+    }
+
+    public void writePayload(Section section) throws IOException {
+        out.writeInt(Section.PORTABLE_STORAGE_SIGNATUREA);
+        out.writeInt(Section.PORTABLE_STORAGE_SIGNATUREB);
+        out.writeByte(Section.PORTABLE_STORAGE_FORMAT_VER);
+        putSection(section);
+    }
+
+    private void writeSection(Section section) throws IOException {
+        out.writeByte(Section.SERIALIZE_TYPE_OBJECT);
+        putSection(section);
+    }
+
+    private void putSection(Section section) throws IOException {
+        writeVarint(section.size());
+        for (Map.Entry<String, Object> kv : section.entrySet()) {
+            byte[] key = kv.getKey().getBytes(StandardCharsets.US_ASCII);
+            out.writeByte(key.length);
+            out.write(key);
+            write(kv.getValue());
+        }
+    }
+
+    private void writeVarint(long i) throws IOException {
+        if (i <= 63) {
+            out.writeByte(((int) i << 2) | Section.PORTABLE_RAW_SIZE_MARK_BYTE);
+        } else if (i <= 16383) {
+            out.writeShort(((int) i << 2) | Section.PORTABLE_RAW_SIZE_MARK_WORD);
+        } else if (i <= 1073741823) {
+            out.writeInt(((int) i << 2) | Section.PORTABLE_RAW_SIZE_MARK_DWORD);
+        } else {
+            if (i > 4611686018427387903L)
+                throw new IllegalArgumentException();
+            out.writeLong((i << 2) | Section.PORTABLE_RAW_SIZE_MARK_INT64);
+        }
+    }
+
+    private void write(Object object) throws IOException {
+        if (object instanceof byte[]) {
+            byte[] value = (byte[]) object;
+            out.writeByte(Section.SERIALIZE_TYPE_STRING);
+            writeVarint(value.length);
+            out.write(value);
+        } else if (object instanceof String) {
+            byte[] value = ((String) object)
+                    .getBytes(StandardCharsets.US_ASCII);
+            out.writeByte(Section.SERIALIZE_TYPE_STRING);
+            writeVarint(value.length);
+            out.write(value);
+        } else if (object instanceof Integer) {
+            out.writeByte(Section.SERIALIZE_TYPE_UINT32);
+            out.writeInt((int) object);
+        } else if (object instanceof Long) {
+            out.writeByte(Section.SERIALIZE_TYPE_UINT64);
+            out.writeLong((long) object);
+        } else if (object instanceof Byte) {
+            out.writeByte(Section.SERIALIZE_TYPE_UINT8);
+            out.writeByte((byte) object);
+        } else if (object instanceof Section) {
+            writeSection((Section) object);
+        } else {
+            throw new IllegalArgumentException();
+        }
+    }
+}

app/src/main/java/com/m2049r/xmrwallet/BaseActivity.java

@@ -50,19 +50,19 @@ public class BaseActivity extends SecureActivity implements GenerateReviewFragme
 
     @Override
     public void showProgressDialog(int msgId) {
-        showProgressDialog(msgId, 0);
+        showProgressDialog(msgId, 250); // don't show dialog for fast operations
     }
 
-    public void showProgressDialog(int msgId, long delay) {
+    public void showProgressDialog(int msgId, long delayMillis) {
         dismissProgressDialog(); // just in case
         progressDialog = new SimpleProgressDialog(BaseActivity.this, msgId);
-        if (delay > 0) {
+        if (delayMillis > 0) {
             Handler handler = new Handler();
             handler.postDelayed(new Runnable() {
                 public void run() {
                     if (progressDialog != null) progressDialog.show();
                 }
-            }, delay);
+            }, delayMillis);
         } else {
             progressDialog.show();
         }

app/src/main/java/com/m2049r/xmrwallet/GenerateFragment.java

@@ -85,15 +85,15 @@ public class GenerateFragment extends Fragment {
 
         View view = inflater.inflate(R.layout.fragment_generate, container, false);
 
-        etWalletName = (TextInputLayout) view.findViewById(R.id.etWalletName);
-        etWalletPassword = (TextInputLayout) view.findViewById(R.id.etWalletPassword);
-        llFingerprintAuth = (LinearLayout) view.findViewById(R.id.llFingerprintAuth);
-        etWalletMnemonic = (TextInputLayout) view.findViewById(R.id.etWalletMnemonic);
-        etWalletAddress = (TextInputLayout) view.findViewById(R.id.etWalletAddress);
-        etWalletViewKey = (TextInputLayout) view.findViewById(R.id.etWalletViewKey);
-        etWalletSpendKey = (TextInputLayout) view.findViewById(R.id.etWalletSpendKey);
-        etWalletRestoreHeight = (TextInputLayout) view.findViewById(R.id.etWalletRestoreHeight);
-        bGenerate = (Button) view.findViewById(R.id.bGenerate);
+        etWalletName = view.findViewById(R.id.etWalletName);
+        etWalletPassword = view.findViewById(R.id.etWalletPassword);
+        llFingerprintAuth = view.findViewById(R.id.llFingerprintAuth);
+        etWalletMnemonic = view.findViewById(R.id.etWalletMnemonic);
+        etWalletAddress = view.findViewById(R.id.etWalletAddress);
+        etWalletViewKey = view.findViewById(R.id.etWalletViewKey);
+        etWalletSpendKey = view.findViewById(R.id.etWalletSpendKey);
+        etWalletRestoreHeight = view.findViewById(R.id.etWalletRestoreHeight);
+        bGenerate = view.findViewById(R.id.bGenerate);
 
         etWalletMnemonic.getEditText().setRawInputType(InputType.TYPE_CLASS_TEXT);
         etWalletAddress.getEditText().setRawInputType(InputType.TYPE_TEXT_FLAG_NO_SUGGESTIONS);

app/src/main/java/com/m2049r/xmrwallet/GenerateReviewFragment.java

@@ -91,22 +91,22 @@ public class GenerateReviewFragment extends Fragment {
 
         View view = inflater.inflate(R.layout.fragment_review, container, false);
 
-        scrollview = (ScrollView) view.findViewById(R.id.scrollview);
-        pbProgress = (ProgressBar) view.findViewById(R.id.pbProgress);
-        tvWalletPassword = (TextView) view.findViewById(R.id.tvWalletPassword);
-        tvWalletAddress = (TextView) view.findViewById(R.id.tvWalletAddress);
-        tvWalletViewKey = (TextView) view.findViewById(R.id.tvWalletViewKey);
-        tvWalletSpendKey = (TextView) view.findViewById(R.id.tvWalletSpendKey);
-        tvWalletMnemonic = (TextView) view.findViewById(R.id.tvWalletMnemonic);
-        bCopyAddress = (ImageButton) view.findViewById(R.id.bCopyAddress);
-        bAdvancedInfo = (Button) view.findViewById(R.id.bAdvancedInfo);
-        llAdvancedInfo = (LinearLayout) view.findViewById(R.id.llAdvancedInfo);
-        llPassword = (LinearLayout) view.findViewById(R.id.llPassword);
-        llMnemonic = (LinearLayout) view.findViewById(R.id.llMnemonic);
-        llSpendKey = (LinearLayout) view.findViewById(R.id.llSpendKey);
-        llViewKey = (LinearLayout) view.findViewById(R.id.llViewKey);
+        scrollview = view.findViewById(R.id.scrollview);
+        pbProgress = view.findViewById(R.id.pbProgress);
+        tvWalletPassword = view.findViewById(R.id.tvWalletPassword);
+        tvWalletAddress = view.findViewById(R.id.tvWalletAddress);
+        tvWalletViewKey = view.findViewById(R.id.tvWalletViewKey);
+        tvWalletSpendKey = view.findViewById(R.id.tvWalletSpendKey);
+        tvWalletMnemonic = view.findViewById(R.id.tvWalletMnemonic);
+        bCopyAddress = view.findViewById(R.id.bCopyAddress);
+        bAdvancedInfo = view.findViewById(R.id.bAdvancedInfo);
+        llAdvancedInfo = view.findViewById(R.id.llAdvancedInfo);
+        llPassword = view.findViewById(R.id.llPassword);
+        llMnemonic = view.findViewById(R.id.llMnemonic);
+        llSpendKey = view.findViewById(R.id.llSpendKey);
+        llViewKey = view.findViewById(R.id.llViewKey);
 
-        bAccept = (Button) view.findViewById(R.id.bAccept);
+        bAccept = view.findViewById(R.id.bAccept);
 
         boolean allowCopy = WalletManager.getInstance().getNetworkType() != NetworkType.NetworkType_Mainnet;
         tvWalletMnemonic.setTextIsSelectable(allowCopy);
@@ -200,7 +200,8 @@ public class GenerateReviewFragment extends Fragment {
             super.onPreExecute();
             showProgress();
             if ((walletPath != null)
-                    && (WalletManager.getInstance().queryWalletHardware(walletPath + ".keys", getPassword()) == 1)
+                    && (WalletManager.getInstance().queryWalletDevice(walletPath + ".keys", getPassword())
+                    == Wallet.Device.Device_Ledger)
                     && (progressCallback != null)) {
                 progressCallback.showLedgerProgressDialog(LedgerProgressDialog.TYPE_RESTORE);
                 dialogOpened = true;
@@ -231,10 +232,15 @@ public class GenerateReviewFragment extends Fragment {
 
             address = wallet.getAddress();
             seed = wallet.getSeed();
-            if (wallet.isKeyOnDevice()) {
-                viewKey = Ledger.Key();
-            } else {
-                viewKey = wallet.getSecretViewKey();
+            switch (wallet.getDeviceType()) {
+                case Device_Ledger:
+                    viewKey = Ledger.Key();
+                    break;
+                case Device_Software:
+                    viewKey = wallet.getSecretViewKey();
+                    break;
+                default:
+                    throw new IllegalStateException("Hardware backing not supported. At all!");
             }
             spendKey = isWatchOnly ? getActivity().getString(R.string.label_watchonly) : wallet.getSecretSpendKey();
             isWatchOnly = wallet.isWatchOnly();
@@ -475,13 +481,13 @@ public class GenerateReviewFragment extends Fragment {
         AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(getActivity());
         alertDialogBuilder.setView(promptsView);
 
-        final TextInputLayout etPasswordA = (TextInputLayout) promptsView.findViewById(R.id.etWalletPasswordA);
+        final TextInputLayout etPasswordA = promptsView.findViewById(R.id.etWalletPasswordA);
         etPasswordA.setHint(getString(R.string.prompt_changepw, walletName));
 
-        final TextInputLayout etPasswordB = (TextInputLayout) promptsView.findViewById(R.id.etWalletPasswordB);
+        final TextInputLayout etPasswordB = promptsView.findViewById(R.id.etWalletPasswordB);
         etPasswordB.setHint(getString(R.string.prompt_changepwB, walletName));
 
-        LinearLayout llFingerprintAuth = (LinearLayout) promptsView.findViewById(R.id.llFingerprintAuth);
+        LinearLayout llFingerprintAuth = promptsView.findViewById(R.id.llFingerprintAuth);
         final Switch swFingerprintAllowed = (Switch) llFingerprintAuth.getChildAt(0);
         if (FingerprintHelper.isDeviceSupported(getActivity())) {
             llFingerprintAuth.setVisibility(View.VISIBLE);