Upstream: Launch WebApkActivity from WebAPK.

chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappLauncherActivity.java

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.chrome.browser.webapps;
 
 import android.app.Activity;
 import android.content.Intent;
 import android.net.Uri;
 import android.os.Build;
 import android.os.Bundle;
 import android.util.Base64;
 
 import org.chromium.base.ApiCompatibilityUtils;
 import org.chromium.base.ApplicationStatus;
+import org.chromium.base.CommandLine;
 import org.chromium.base.ContextUtils;
 import org.chromium.base.Log;
+import org.chromium.chrome.browser.ChromeSwitches;
 import org.chromium.chrome.browser.IntentHandler;
 import org.chromium.chrome.browser.ShortcutHelper;
 import org.chromium.chrome.browser.document.ChromeLauncherActivity;
 import org.chromium.chrome.browser.metrics.LaunchMetrics;
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.chrome.browser.util.IntentUtils;
+import org.chromium.webapk.lib.client.WebApkValidator;
 
 import java.lang.ref.WeakReference;
 
 /**
  * Launches web apps.  This was separated from the ChromeLauncherActivity because the
  * ChromeLauncherActivity is not allowed to be excluded from Android's Recents: crbug.com/517426.
  */
 public class WebappLauncherActivity extends Activity {
     /**
      * Action fired when an Intent is trying to launch a WebappActivity.
@@ skipping 10 matching lines @@
         if (webappInfo == null) {
             super.onCreate(null);
             ApiCompatibilityUtils.finishAndRemoveTask(this);
             return;
         }
 
         super.onCreate(savedInstanceState);
         Intent intent = getIntent();
         String webappId = webappInfo.id();
         String webappUrl = webappInfo.uri().toString();
+        String webappPackageName = webappInfo.packageName();
         int webappSource = webappInfo.source();
 
         if (webappId != null && webappUrl != null) {
-            String webappMacString = IntentUtils.safeGetStringExtra(
-                    intent, ShortcutHelper.EXTRA_MAC);
-            byte[] webappMac =
-                    webappMacString == null ? null : Base64.decode(webappMacString, Base64.DEFAULT);
-
             Intent launchIntent = null;
 
-            // Permit the launch to a standalone web app frame if the intent was sent by Chrome, or
-            // if the MAC is present and valid for the URL to be opened.
-            boolean isTrusted = IntentHandler.wasIntentSenderChrome(intent,
-                    ContextUtils.getApplicationContext());
-            boolean isUrlValid = (webappMac != null
-                    && WebappAuthenticator.isUrlValid(this, webappUrl, webappMac));
-
-            if (isTrusted || isUrlValid) {
+            // Permit the launch to a standalone web app frame if:
+            // - the request was for a WebAPK that is valid
+            // - the MAC is present and valid for the homescreen shortcut to be opened.
+            // - the intent was sent by Chrome
+            boolean isWebApk = CommandLine.getInstance().hasSwitch(ChromeSwitches.ENABLE_WEBAPK)
+                    && isValidWebApk(webappPackageName, webappUrl);
+            if (isWebApk
+                    || isValidFullscreenPwa(webappUrl, IntentUtils.safeGetStringExtra(
+                            intent, ShortcutHelper.EXTRA_MAC))
+                    || wasIntentFromChrome(intent)) {

[pkotwicz, 2016/05/18 23:00:17]

The security review will take a lot of time (and it should take a lot of time).
For the initial upstream CL, can we do:
if (webappInfo.getWebApkPackage() != null &&
    !isValidWebApk(webappPackageName)) {
    isUrlValid = false;
}

In the initial version:
- We will not change the mac checking logic
- isValidWebApk() will only check the prefix and whether
ChromeSwitches.ENABLE_WEBAPK is set

[Xi Han, 2016/05/19 18:31:50]

Good idea, since the security check isn't the focus of this CL.

                 LaunchMetrics.recordHomeScreenLaunchIntoStandaloneActivity(webappUrl, webappSource);
 
                 String activityName = WebappActivity.class.getName();
                 if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
                     // Specifically assign the app to a particular WebappActivity instance.
                     int activityIndex = ActivityAssigner.instance(this).assign(webappId);
                     activityName += String.valueOf(activityIndex);
                 }
 
                 // Create an intent to launch the Webapp in an unmapped WebappActivity.
                 launchIntent = new Intent();
                 launchIntent.setClassName(this, activityName);
                 webappInfo.setWebappIntentExtras(launchIntent);
 
                 // On L+, firing intents with the exact same data should relaunch a particular
                 // Activity.
                 launchIntent.setAction(Intent.ACTION_VIEW);
                 launchIntent.setData(Uri.parse(WebappActivity.WEBAPP_SCHEME + "://" + webappId));
             } else {
                 Log.e(TAG, "Shortcut (%s) opened in Chrome.", webappUrl);
 
                 // The shortcut data doesn't match the current encoding.  Change the intent action
                 // launch the URL with a VIEW Intent in the regular browser.
                 launchIntent = new Intent(Intent.ACTION_VIEW, Uri.parse(webappUrl));
                 launchIntent.setClassName(getPackageName(), ChromeLauncherActivity.class.getName());
-                launchIntent.putExtra(ShortcutHelper.REUSE_URL_MATCHING_TAB_ELSE_NEW_TAB, true);
-                launchIntent.putExtra(ShortcutHelper.EXTRA_SOURCE, webappSource);
             }
-
-            launchIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK
-                    | ApiCompatibilityUtils.getActivityNewDocumentFlag());
+            if (!isWebApk) {
+                launchIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK
+                        | ApiCompatibilityUtils.getActivityNewDocumentFlag());
+            }
             startActivity(launchIntent);
         }
 
         ApiCompatibilityUtils.finishAndRemoveTask(this);
     }
 
     /**
+     * Checks whether the package being targeted is a valid WebAPK and whether the url supplied
+     * can be fulfilled by that WebAPK.
+     * @param webapkPackage The package name of the requested WebAPK
+     * @param url The url to navigate to
+     * @return true iff all validation criteria are met
+     */
+    private boolean isValidWebApk(String webapkPackage, String url) {
+        boolean isValidWebApk = WebApkValidator.isValidWebApk(this, webapkPackage);
+        if (!isValidWebApk) {
+            Log.d(TAG, "isValidWebApk(pkg=\"" + webapkPackage + "\",url=\"" + url + "\")=false");
+            return false;
+        }
+
+        boolean result = webapkPackage != null
+                && webapkPackage.equals(WebApkValidator.queryWebApkPackage(this, url));
+        Log.d(TAG, "isValidWebApk(pkg=\"" + webapkPackage + "\",url=\"" + url + "\")=" + result);
+        return result;
+    }
+
+    /**
+     * Returns whether the MAC is present and valid for the fullscreen PWA to be opened.
+     * @param url the url to launch
+     * @param mac the MAC code provided which must match the requested url
+     * @return whether the supplied MAC is valid for the supplied url
+     */
+    private boolean isValidFullscreenPwa(String url, String mac) {
+        return mac != null
+                && WebappAuthenticator.isUrlValid(this, url, Base64.decode(mac, Base64.DEFAULT));
+    }
+
+    private boolean wasIntentFromChrome(Intent intent) {
+        return IntentHandler.wasIntentSenderChrome(intent,
+                ContextUtils.getApplicationContext());
+    }
+
+    /**
      * Brings a live WebappActivity back to the foreground if one exists for the given tab ID.
      * @param tabId ID of the Tab to bring back to the foreground.
      * @return True if a live WebappActivity was found, false otherwise.
      */
     public static boolean bringWebappToFront(int tabId) {
         if (tabId == Tab.INVALID_TAB_ID) return false;
 
         for (WeakReference<Activity> activityRef : ApplicationStatus.getRunningActivities()) {
             Activity activity = activityRef.get();
             if (activity == null || !(activity instanceof WebappActivity)) continue;
 
             WebappActivity webappActivity = (WebappActivity) activity;
             if (webappActivity.getActivityTab() != null
                     && webappActivity.getActivityTab().getId() == tabId) {
                 Tab tab = webappActivity.getActivityTab();
                 tab.getTabWebContentsDelegateAndroid().activateContents();
                 return true;
             }
         }
 
         return false;
     }
 }