Repository: rafaeltoledo/android-security Branch: master Commit: 2ca3680b911b Files: 26 Total size: 40.4 KB Directory structure: gitextract_7hjh6zbc/ ├── .gitignore ├── LICENSE.txt ├── README.md ├── app/ │ ├── .gitignore │ ├── build.gradle │ ├── proguard-rules.pro │ └── src/ │ └── main/ │ ├── AndroidManifest.xml │ ├── java/ │ │ └── net/ │ │ └── rafaeltoledo/ │ │ └── security/ │ │ ├── SecurityApp.java │ │ ├── http/ │ │ │ ├── HttpClientProvider.java │ │ │ └── Tls12SslSocketFactory.java │ │ ├── ui/ │ │ │ ├── MainActivity.java │ │ │ └── MainController.java │ │ └── util/ │ │ ├── EnvironmentChecker.java │ │ ├── InstallationChecker.java │ │ └── SignatureUtils.java │ └── res/ │ ├── layout/ │ │ └── activity_main.xml │ └── values/ │ ├── colors.xml │ ├── strings.xml │ └── styles.xml ├── build.gradle ├── gradle/ │ └── wrapper/ │ ├── gradle-wrapper.jar │ └── gradle-wrapper.properties ├── gradle.properties ├── gradlew ├── gradlew.bat └── settings.gradle ================================================ FILE CONTENTS ================================================ ================================================ FILE: .gitignore ================================================ *.iml .gradle /local.properties /.idea .DS_Store /build /captures .externalNativeBuild ================================================ FILE: LICENSE.txt ================================================ Apache License Version 2.0, January 2004 http://www.apache.org/licenses/ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 1. 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We also recommend that a file or class name and description of purpose be included on the same "printed page" as the copyright notice for easier identification within third-party archives. Copyright 2017 Rafael Toledo 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. ================================================ FILE: README.md ================================================ # Android Security Sandbox A sandbox app with some tools and code to help you to better secure your Android apps. [Related presentation - pt-BR](https://speakerdeck.com/rafaeltoledo/seguranca-no-android-1) ## This sample includes 1. Obfuscation using Proguard and `android-proguard-optimize` rules 2. Encrypted database storage using [SQLCipher](https://www.zetetic.net/sqlcipher/sqlcipher-for-android) 3. Encrypted key-value storage using [Hawk](https://github.com/orhanobut/hawk), powered by [Conceal](https://facebook.github.io/conceal/) 4. Device checking using [SafetyNet](https://developers.google.com/android/reference/com/google/android/gms/safetynet/SafetyNet) 5. Root detection using [RootBeer](https://github.com/scottyab/rootbeer) 6. HTTP pinning using [OkHttp](https://github.com/square/okhttp/wiki/HTTPS) 7. Other environment checks, like *Debug*, *Emulator*, *Installation Source*, and *Tampering* ================================================ FILE: app/.gitignore ================================================ /build ================================================ FILE: app/build.gradle ================================================ apply plugin: 'com.android.application' android { compileSdkVersion 25 buildToolsVersion '25.0.3' defaultConfig { applicationId 'net.rafaeltoledo.security' minSdkVersion 16 targetSdkVersion 25 versionCode 1 versionName '1.0.0' testInstrumentationRunner 'android.support.test.runner.AndroidJUnitRunner' manifestPlaceholders = [ SAFETYNET_API_KEY: System.getenv('SAFETYNET_API_KEY') ] } dataBinding.enabled true compileOptions { sourceCompatibility JavaVersion.VERSION_1_8 targetCompatibility JavaVersion.VERSION_1_8 } signingConfigs { release { storeFile file(System.getenv('PROJECT_STORE_FILE')) storePassword System.getenv('PROJECT_STORE_PASSWORD') keyAlias System.getenv('PROJECT_KEY_ALIAS') keyPassword System.getenv('PROJECT_KEY_PASSWORD') } } buildTypes { release { minifyEnabled true shrinkResources true proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro' signingConfig signingConfigs.release } } } dependencies { compile 'com.android.support:appcompat-v7:25.3.1' compile 'com.scottyab:rootbeer-lib:0.0.6' compile 'com.orhanobut:hawk:2.0.1' compile 'com.google.code.gson:gson:2.8.0' // Forcing latest GSON compile 'net.zetetic:android-database-sqlcipher:3.5.7@aar' compile 'com.squareup.okhttp3:okhttp:3.7.0' compile 'com.google.android.gms:play-services-safetynet:10.2.4' } ================================================ FILE: app/proguard-rules.pro ================================================ -dontwarn java.nio.file.* -dontwarn org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement -dontwarn okio.** -dontwarn okhttp3.** -keepattributes Signature -keepattributes EnclosingMethod -keepattributes *Annotation* -keep class sun.misc.Unsafe { *; } -keep class okhttp3.** { *; } -keep interface okhttp3.** { *; } -keep class com.google.gson.stream.** { *; } -keep class net.sqlcipher.** { *; } -keep class net.sqlcipher.database.** { *; } -assumenosideeffects class android.util.Log { public static boolean isLoggable(java.lang.String, int); public static int v(...); public static int i(...); public static int w(...); public static int d(...); public static int e(...); } ================================================ FILE: app/src/main/AndroidManifest.xml ================================================ ================================================ FILE: app/src/main/java/net/rafaeltoledo/security/SecurityApp.java ================================================ package net.rafaeltoledo.security; import android.app.Application; import android.util.Log; import com.orhanobut.hawk.Hawk; import net.sqlcipher.database.SQLiteDatabase; public class SecurityApp extends Application { private static final String TAG = SecurityApp.class.getSimpleName(); private static final String PREF_TIMES = "net.rafaeltoledo.security.PREF_TIMES"; @Override public void onCreate() { super.onCreate(); Hawk.init(this).build(); SQLiteDatabase.loadLibs(this); int times = Hawk.get(PREF_TIMES, 0) + 1; Log.d(TAG, "Psss! Let me tell a secret: you opened this app " + times + " times."); Hawk.put(PREF_TIMES, times); } } ================================================ FILE: app/src/main/java/net/rafaeltoledo/security/http/HttpClientProvider.java ================================================ package net.rafaeltoledo.security.http; import android.util.Log; import java.security.GeneralSecurityException; import java.security.KeyStore; import java.util.Collections; import javax.net.ssl.TrustManager; import javax.net.ssl.TrustManagerFactory; import javax.net.ssl.X509TrustManager; import okhttp3.CertificatePinner; import okhttp3.ConnectionSpec; import okhttp3.OkHttpClient; import okhttp3.TlsVersion; public class HttpClientProvider { private static final String TAG = HttpClientProvider.class.getSimpleName(); private static final OkHttpClient CLIENT = init(); private static OkHttpClient init() { ConnectionSpec.Builder spec = new ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS) .tlsVersions(TlsVersion.TLS_1_2); OkHttpClient.Builder client = new OkHttpClient.Builder() .connectionSpecs(Collections.singletonList(spec.build())); // This setup is necessary because API 16-18 support TLS 1.2, // but use 1.0 as default. setupTls(client); setupPinning(client); return client.build(); } private static void setupPinning(OkHttpClient.Builder client) { client.certificatePinner(new CertificatePinner.Builder() .add("github.com", "sha256/pL1+qb9HTMRZJmuC/bB/ZI9d302BYrrqiVuRyW+DGrU=") .add("github.com", "sha256/RRM1dGqnDFsCJXBTHky16vi1obOlCgFFn/yOhI/y+ho=") .add("github.com", "sha256/WoiWRyIOVNa9ihaBciRSC7XHjliYS9VwUGOIud4PB18=") .build()); } private static void setupTls(OkHttpClient.Builder builder) { try { TrustManagerFactory factory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm()); factory.init((KeyStore) null); for (TrustManager trustManager : factory.getTrustManagers()) { if (trustManager instanceof X509TrustManager) { builder.sslSocketFactory(new Tls12SslSocketFactory(), (X509TrustManager) trustManager); break; } } } catch (GeneralSecurityException e) { Log.e(TAG, "Failed to initialize SSL Socket Factory", e); } } public static OkHttpClient getClient() { return CLIENT; } } ================================================ FILE: app/src/main/java/net/rafaeltoledo/security/http/Tls12SslSocketFactory.java ================================================ package net.rafaeltoledo.security.http; import java.io.IOException; import java.net.InetAddress; import java.net.Socket; import javax.net.ssl.SSLSocket; import javax.net.ssl.SSLSocketFactory; public class Tls12SslSocketFactory extends SSLSocketFactory { private final String tag = "TLSv1.2"; private SSLSocketFactory delegate; public Tls12SslSocketFactory() { delegate = (SSLSocketFactory) SSLSocketFactory.getDefault(); } @Override public String[] getDefaultCipherSuites() { return delegate.getDefaultCipherSuites(); } @Override public String[] getSupportedCipherSuites() { return delegate.getSupportedCipherSuites(); } @Override public Socket createSocket(Socket socket, String host, int port, boolean autoClose) throws IOException { SSLSocket s = (SSLSocket) delegate.createSocket(socket, host, port, autoClose); s.setEnabledProtocols(new String[]{tag}); return s; } @Override public Socket createSocket(String host, int port) throws IOException { SSLSocket s = (SSLSocket) delegate.createSocket(host, port); s.setEnabledProtocols(new String[]{tag}); return s; } @Override public Socket createSocket(String host, int port, InetAddress localHost, int localPort) throws IOException { SSLSocket s = (SSLSocket) delegate.createSocket(host, port, localHost, localPort); s.setEnabledProtocols(new String[]{tag}); return s; } @Override public Socket createSocket(InetAddress host, int port) throws IOException { SSLSocket s = (SSLSocket) delegate.createSocket(host, port); s.setEnabledProtocols(new String[]{tag}); return s; } @Override public Socket createSocket(InetAddress address, int port, InetAddress localAddress, int localPort) throws IOException { SSLSocket s = (SSLSocket) delegate.createSocket(address, port, localAddress, localPort); s.setEnabledProtocols(new String[]{tag}); return s; } } ================================================ FILE: app/src/main/java/net/rafaeltoledo/security/ui/MainActivity.java ================================================ package net.rafaeltoledo.security.ui; import android.databinding.DataBindingUtil; import android.os.Build; import android.os.Bundle; import android.support.annotation.NonNull; import android.support.annotation.Nullable; import android.support.v7.app.AppCompatActivity; import android.util.Log; import com.google.android.gms.common.ConnectionResult; import com.google.android.gms.common.api.GoogleApiClient; import com.google.android.gms.safetynet.SafetyNet; import com.scottyab.rootbeer.RootBeer; import net.rafaeltoledo.security.R; import net.rafaeltoledo.security.databinding.ActivityMainBinding; import net.rafaeltoledo.security.http.HttpClientProvider; import net.rafaeltoledo.security.http.Tls12SslSocketFactory; import net.rafaeltoledo.security.util.EnvironmentChecker; import net.rafaeltoledo.security.util.InstallationChecker; import net.rafaeltoledo.security.util.SignatureUtils; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.security.GeneralSecurityException; import java.security.KeyStore; import java.security.SecureRandom; import java.util.Collections; import java.util.Random; import javax.net.ssl.TrustManager; import javax.net.ssl.TrustManagerFactory; import javax.net.ssl.X509TrustManager; import okhttp3.Call; import okhttp3.Callback; import okhttp3.ConnectionSpec; import okhttp3.OkHttpClient; import okhttp3.Request; import okhttp3.Response; import okhttp3.TlsVersion; public class MainActivity extends AppCompatActivity implements GoogleApiClient.OnConnectionFailedListener, MainController { private static final String TAG = MainActivity.class.getSimpleName(); private GoogleApiClient client; private final Random random = new SecureRandom(); @Override protected void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); ActivityMainBinding binding = DataBindingUtil.setContentView(this, R.layout.activity_main); client = new GoogleApiClient.Builder(this) .addApi(SafetyNet.API) .enableAutoManage(this, this) .build(); binding.root.setText(new RootBeer(this).isRooted() ? "Device is rooted" : "Device isn't rooted"); binding.installation.setText(InstallationChecker.verifyInstaller(this) ? "Installed from Play Store" : "Installed from unknown source"); binding.enviroment.setText((EnvironmentChecker.alternativeIsEmulator() ? "Running on an emulator" : "Running on a device") + (EnvironmentChecker.isDebuggable(this) ? " with debugger" : "")); binding.tampering.setText((InstallationChecker.checkPackage(this) ? "The package is consistent" : "The package was modified") + (SignatureUtils.checkSignature(this) ? " and the signature is ok" : " and the signature was changed!")); binding.setController(this); } @Override public void onConnectionFailed(@NonNull ConnectionResult connectionResult) { Log.e(TAG, "Failed to connect to Google Client"); } @Override public void requestSafetyNetCheck() { byte[] nonce = getRequestNonce(); SafetyNet.SafetyNetApi.attest(client, nonce) .setResultCallback(result -> { if (result.getStatus().isSuccess()) { showSafetyNetResult(result.getJwsResult()); } else { Log.e(TAG, "Error on SafetyNet request - Code (" + result.getStatus().getStatusCode() + "): " + "" + result.getStatus().getStatusMessage()); } }); } @Override public void performOkHttpRequest() { OkHttpClient client = HttpClientProvider.getClient(); Request request = new Request.Builder() .url("https://github.com/robots.txt") .build(); client.newCall(request).enqueue(new Callback() { @Override public void onFailure(Call call, IOException e) { Log.e(TAG, "Failed to perform request", e); } @Override public void onResponse(Call call, Response response) throws IOException { Log.d(TAG, response.body().string()); } }); } private void showSafetyNetResult(String result) { /* Forward this result to your server together with the nonce for verification. You can also parse the JwsResult locally to confirm that the API returned a response by checking for an 'error' field first and before retrying the request with an exponential backoff. NOTE: Do NOT rely on a local, client-side only check for security, you must verify the response on a remote server! */ Log.d(TAG, "Success! SafetyNet result:\n" + result + "\n"); } // Ideally, the Nonce should be generated in your server private byte[] getRequestNonce() { String nonceData = "SafetyNet Sample: " + System.currentTimeMillis(); ByteArrayOutputStream byteStream = new ByteArrayOutputStream(); byte[] bytes = new byte[24]; random.nextBytes(bytes); try { byteStream.write(bytes); byteStream.write(nonceData.getBytes()); } catch (IOException e) { Log.e(TAG, "Failed to generate nonce", e); return null; } return byteStream.toByteArray(); } } ================================================ FILE: app/src/main/java/net/rafaeltoledo/security/ui/MainController.java ================================================ package net.rafaeltoledo.security.ui; public interface MainController { void requestSafetyNetCheck(); void performOkHttpRequest(); } ================================================ FILE: app/src/main/java/net/rafaeltoledo/security/util/EnvironmentChecker.java ================================================ package net.rafaeltoledo.security.util; import android.content.Context; import android.content.pm.ApplicationInfo; import android.os.Build; import android.util.Log; public class EnvironmentChecker { private static final String TAG = EnvironmentChecker.class.getSimpleName(); private static String getSystemProperty(String name) throws Exception { Class systemPropertyClass = Class.forName("android.os.SystemProperties"); return (String) systemPropertyClass.getMethod("get", new Class[]{String.class}) .invoke(systemPropertyClass, name); } public static boolean alternativeIsEmulator() { return Build.FINGERPRINT.startsWith("generic") || Build.FINGERPRINT.startsWith("unknown") || Build.MODEL.contains("google_sdk") || Build.MODEL.contains("Emulator") || Build.MODEL.contains("Android SDK built for x86") || Build.MANUFACTURER.contains("Genymotion") || (Build.BRAND.startsWith("generic") && Build.DEVICE.startsWith("generic")) || "google_sdk".equals(Build.PRODUCT) || "goldfish".equals(Build.HARDWARE); } public static boolean isEmulator() { try { boolean goldfish = getSystemProperty("ro.hardware").contains("goldfish"); boolean emu = getSystemProperty("ro.kernel.qemu").length() > 0; boolean sdk = getSystemProperty("ro.product.model").equals("sdk"); if (emu || goldfish || sdk) { return true; } } catch (Exception e) { Log.d(TAG, "Failed to check enviroment", e); } return false; } public static boolean isDebuggable(Context context) { return (context.getApplicationInfo().flags & ApplicationInfo.FLAG_DEBUGGABLE) != 0; } } ================================================ FILE: app/src/main/java/net/rafaeltoledo/security/util/InstallationChecker.java ================================================ package net.rafaeltoledo.security.util; import android.content.Context; public class InstallationChecker { private static final String GOOGLE_PLAY = "com.android.vending"; private static final String ORIGINAL_PACKAGE = "net.rafaeltoledo.security"; public static boolean verifyInstaller(Context context) { final String installer = context.getPackageManager() .getInstallerPackageName(context.getPackageName()); return installer != null && installer.compareTo(GOOGLE_PLAY) == 0; } public static boolean checkPackage(Context context) { return context.getPackageName().compareTo(ORIGINAL_PACKAGE) == 0; } } ================================================ FILE: app/src/main/java/net/rafaeltoledo/security/util/SignatureUtils.java ================================================ package net.rafaeltoledo.security.util; import android.content.Context; import android.content.pm.PackageInfo; import android.content.pm.PackageManager; import android.content.pm.Signature; import android.util.Base64; import android.util.Log; import java.security.MessageDigest; public class SignatureUtils { private static final String TAG = SignatureUtils.class.getSimpleName(); private static final String SIGNATURE = "0P333z1O57jHJ87piTMi3W6VuQU=\n"; public static boolean checkSignature(Context context) { try { PackageInfo packageInfo = context.getPackageManager() .getPackageInfo(context.getPackageName(), PackageManager.GET_SIGNATURES); for (Signature signature : packageInfo.signatures) { MessageDigest sha = MessageDigest.getInstance("SHA"); sha.update(signature.toByteArray()); final String currentSignature = Base64.encodeToString(sha.digest(), Base64.DEFAULT); if (SIGNATURE.equals(currentSignature)) { return true; } } } catch (Exception e) { Log.e(TAG, "Failed to check signature", e); } return false; } } ================================================ FILE: app/src/main/res/layout/activity_main.xml ================================================