Add SafetyNet check

app/build.gradle

@@ -2,7 +2,7 @@ apply plugin: 'com.android.application'
 
 android {
     compileSdkVersion 25
-    buildToolsVersion "25.0.1"
+    buildToolsVersion "25.0.2"
 
     defaultConfig {
         applicationId "com.topjohnwu.magisk"
@@ -49,9 +49,9 @@ repositories {
 
 dependencies {
     compile fileTree(include: ['*.jar'], dir: 'libs')
-    compile 'com.android.support:recyclerview-v7:25.0.1'
+    compile 'com.android.support:recyclerview-v7:25.1.0'
-    compile 'com.android.support:cardview-v7:25.0.1'
+    compile 'com.android.support:cardview-v7:25.1.0'
-    compile 'com.android.support:design:25.0.1'
+    compile 'com.android.support:design:25.1.0'
     compile 'com.jakewharton:butterknife:8.4.0'
     compile 'com.google.code.gson:gson:2.8.0'
     compile 'com.github.clans:fab:1.6.4'
@@ -59,5 +59,6 @@ dependencies {
     compile 'com.madgag.spongycastle:prov:1.54.0.0'
     compile 'com.madgag.spongycastle:pkix:1.54.0.0'
     compile 'com.madgag.spongycastle:pg:1.54.0.0'
+    compile 'com.google.android.gms:play-services-safetynet:10.0.1'
     annotationProcessor 'com.jakewharton:butterknife-compiler:8.4.0'
 }

app/src/main/AndroidManifest.xml

@@ -52,6 +52,10 @@
                 android:resource="@xml/file_paths" />
         </provider>
 
+        <meta-data
+            android:name="com.google.android.gms.version"
+            android:value="@integer/google_play_services_version" />
+
     </application>
 
 </manifest>

app/src/main/java/com/topjohnwu/magisk/SplashActivity.java

@@ -5,9 +5,11 @@ import android.content.SharedPreferences;
 import android.os.Bundle;
 import android.preference.PreferenceManager;
 import android.support.v7.app.AppCompatActivity;
+import android.widget.Toast;
 
 import com.topjohnwu.magisk.utils.Async;
 import com.topjohnwu.magisk.utils.Logger;
+import com.topjohnwu.magisk.utils.SafetyNetHelper;
 import com.topjohnwu.magisk.utils.Utils;
 
 public class SplashActivity extends AppCompatActivity {
@@ -36,6 +38,24 @@ public class SplashActivity extends AppCompatActivity {
                 .putBoolean("hosts", Utils.itemExist(false, "/magisk/.core/hosts"))
                 .apply();
 
+        // Simple POC for checking SN status
+        new SafetyNetHelper(getApplicationContext()) {
+            @Override
+            public void handleResults(int i) {
+                switch (i) {
+                    case -1:
+                        Toast.makeText(mContext, "SN: Error", Toast.LENGTH_LONG).show();
+                        break;
+                    case 0:
+                        Toast.makeText(mContext, "SN: Fail", Toast.LENGTH_LONG).show();
+                        break;
+                    case 1:
+                        Toast.makeText(mContext, "SN: Success", Toast.LENGTH_LONG).show();
+                        break;
+                }
+            }
+        }.requestTest();
+
         new Async.CheckUpdates(prefs).exec();
 
         new Async.LoadModules(prefs) {

app/src/main/java/com/topjohnwu/magisk/utils/Async.java

@@ -178,10 +178,10 @@ public class Async {
                 Logger.dev("FlashZip: File created successfully - " + mCachedFile.getPath());
                 in.close();
             } catch (FileNotFoundException e) {
-                Log.e(Logger.LOG_TAG, "FlashZip: Invalid Uri");
+                Log.e(Logger.TAG, "FlashZip: Invalid Uri");
                 throw e;
             } catch (IOException e) {
-                Log.e(Logger.LOG_TAG, "FlashZip: Error in creating file");
+                Log.e(Logger.TAG, "FlashZip: Error in creating file");
                 throw e;
             }
         }

app/src/main/java/com/topjohnwu/magisk/utils/Logger.java

@@ -4,23 +4,29 @@ import android.util.Log;
 
 public class Logger {
 
-    public static final String LOG_TAG = "Magisk: DEV";
+    public static final String TAG = "Magisk";
+    public static final String DEV_TAG = "Magisk: DEV";
+    public static final String DEBUG_TAG = "Magisk: DEBUG";
 
     public static boolean logShell, devLog;
 
+    public static void debug(String msg) {
+        Log.d(DEBUG_TAG, msg);
+    }
+
     public static void dev(String msg, Object... args) {
         if (devLog) {
             if (args.length == 1 && args[0] instanceof Throwable) {
-                Log.d(LOG_TAG, msg, (Throwable) args[0]);
+                Log.d(DEV_TAG, msg, (Throwable) args[0]);
             } else {
-                Log.d(LOG_TAG, String.format(msg, args));
+                Log.d(DEV_TAG, String.format(msg, args));
             }
         }
     }
 
     public static void dev(String msg) {
         if (devLog) {
-            Log.d(LOG_TAG, msg);
+            Log.d(DEV_TAG, msg);
         }
     }
 

app/src/main/java/com/topjohnwu/magisk/utils/SafetyNetHelper.java

@@ -0,0 +1,84 @@
+package com.topjohnwu.magisk.utils;
+
+import android.content.Context;
+import android.os.Bundle;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import android.util.Base64;
+
+import com.google.android.gms.common.ConnectionResult;
+import com.google.android.gms.common.api.GoogleApiClient;
+import com.google.android.gms.common.api.Status;
+import com.google.android.gms.safetynet.SafetyNet;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.security.SecureRandom;
+import java.util.Arrays;
+
+public abstract class SafetyNetHelper
+        implements GoogleApiClient.OnConnectionFailedListener, GoogleApiClient.ConnectionCallbacks {
+
+    private GoogleApiClient mGoogleApiClient;
+    protected Context mContext;
+
+    public SafetyNetHelper(Context context) {
+        mContext = context;
+        mGoogleApiClient = new GoogleApiClient.Builder(mContext)
+                .addApi(SafetyNet.API)
+                .addConnectionCallbacks(this)
+                .addOnConnectionFailedListener(this)
+                .build();
+    }
+
+    @Override
+    public void onConnectionFailed(@NonNull ConnectionResult result) {
+        Logger.dev("SN: Google API fail");
+    }
+
+    @Override
+    public void onConnected(@Nullable Bundle bundle) {
+        Logger.dev("SN: Google API Connected");
+        safetyNetCheck();
+    }
+
+    @Override
+    public void onConnectionSuspended(int i) {
+        Logger.dev("SN: Google API Suspended");
+    }
+
+    public void requestTest() {
+        // Connect Google Service
+        mGoogleApiClient.connect();
+    }
+
+    private void safetyNetCheck() {
+        // Create nonce
+        byte[] nonce = new byte[24];
+        new SecureRandom().nextBytes(nonce);
+
+        Logger.dev("SN: Check with nonce: " + Base64.encodeToString(nonce, Base64.DEFAULT));
+
+        // Call SafetyNet
+        SafetyNet.SafetyNetApi.attest(mGoogleApiClient, nonce)
+                .setResultCallback(result -> {
+                    Status status = result.getStatus();
+                    if (status.isSuccess()) {
+                        String json = new String(Base64.decode(result.getJwsResult().split("\\.")[1], Base64.DEFAULT));
+                        Logger.dev("SN: Response: " + json);
+                        try {
+                            JSONObject decoded = new JSONObject(json);
+                            handleResults(decoded.getBoolean("ctsProfileMatch") ? 1 : 0);
+                        } catch (JSONException ignored) {}
+                    } else {
+                        Logger.dev("SN: No response");
+                        handleResults(-1);
+                    }
+                    // Disconnect
+                    mGoogleApiClient.disconnect();
+                });
+    }
+
+    public abstract void handleResults(int i);
+}