1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.captiveportallogin;
18
19import android.app.Activity;
20import android.app.LoadedApk;
21import android.content.Context;
22import android.content.Intent;
23import android.graphics.Bitmap;
24import android.net.CaptivePortal;
25import android.net.ConnectivityManager;
26import android.net.ConnectivityManager.NetworkCallback;
27import android.net.Network;
28import android.net.NetworkCapabilities;
29import android.net.NetworkRequest;
30import android.net.Proxy;
31import android.net.Uri;
32import android.net.http.SslError;
33import android.os.Bundle;
34import android.provider.Settings;
35import android.util.ArrayMap;
36import android.util.Log;
37import android.util.TypedValue;
38import android.view.Menu;
39import android.view.MenuItem;
40import android.webkit.SslErrorHandler;
41import android.webkit.WebChromeClient;
42import android.webkit.WebSettings;
43import android.webkit.WebView;
44import android.webkit.WebViewClient;
45import android.widget.ProgressBar;
46import android.widget.TextView;
47
48import java.io.IOException;
49import java.net.HttpURLConnection;
50import java.net.MalformedURLException;
51import java.net.URL;
52import java.lang.InterruptedException;
53import java.lang.reflect.Field;
54import java.lang.reflect.Method;
55import java.util.Random;
56
57public class CaptivePortalLoginActivity extends Activity {
58    private static final String TAG = "CaptivePortalLogin";
59    private static final int SOCKET_TIMEOUT_MS = 10000;
60
61    private enum Result { DISMISSED, UNWANTED, WANTED_AS_IS };
62
63    private URL mURL;
64    private Network mNetwork;
65    private CaptivePortal mCaptivePortal;
66    private NetworkCallback mNetworkCallback;
67    private ConnectivityManager mCm;
68    private boolean mLaunchBrowser = false;
69    private MyWebViewClient mWebViewClient;
70
71    @Override
72    protected void onCreate(Bundle savedInstanceState) {
73        super.onCreate(savedInstanceState);
74        mCm = ConnectivityManager.from(this);
75        String url = getIntent().getStringExtra(ConnectivityManager.EXTRA_CAPTIVE_PORTAL_URL);
76        if (url == null) url = mCm.getCaptivePortalServerUrl();
77        try {
78            mURL = new URL(url);
79        } catch (MalformedURLException e) {
80            // System misconfigured, bail out in a way that at least provides network access.
81            Log.e(TAG, "Invalid captive portal URL, url=" + url);
82            done(Result.WANTED_AS_IS);
83        }
84        mNetwork = getIntent().getParcelableExtra(ConnectivityManager.EXTRA_NETWORK);
85        mCaptivePortal = getIntent().getParcelableExtra(ConnectivityManager.EXTRA_CAPTIVE_PORTAL);
86
87        // Also initializes proxy system properties.
88        mCm.bindProcessToNetwork(mNetwork);
89
90        // Proxy system properties must be initialized before setContentView is called because
91        // setContentView initializes the WebView logic which in turn reads the system properties.
92        setContentView(R.layout.activity_captive_portal_login);
93
94        getActionBar().setDisplayShowHomeEnabled(false);
95
96        // Exit app if Network disappears.
97        final NetworkCapabilities networkCapabilities = mCm.getNetworkCapabilities(mNetwork);
98        if (networkCapabilities == null) {
99            finishAndRemoveTask();
100            return;
101        }
102        mNetworkCallback = new NetworkCallback() {
103            @Override
104            public void onLost(Network lostNetwork) {
105                if (mNetwork.equals(lostNetwork)) done(Result.UNWANTED);
106            }
107        };
108        final NetworkRequest.Builder builder = new NetworkRequest.Builder();
109        for (int transportType : networkCapabilities.getTransportTypes()) {
110            builder.addTransportType(transportType);
111        }
112        mCm.registerNetworkCallback(builder.build(), mNetworkCallback);
113
114        final WebView myWebView = (WebView) findViewById(R.id.webview);
115        myWebView.clearCache(true);
116        WebSettings webSettings = myWebView.getSettings();
117        webSettings.setJavaScriptEnabled(true);
118        webSettings.setMixedContentMode(WebSettings.MIXED_CONTENT_COMPATIBILITY_MODE);
119        mWebViewClient = new MyWebViewClient();
120        myWebView.setWebViewClient(mWebViewClient);
121        myWebView.setWebChromeClient(new MyWebChromeClient());
122        // Start initial page load so WebView finishes loading proxy settings.
123        // Actual load of mUrl is initiated by MyWebViewClient.
124        myWebView.loadData("", "text/html", null);
125    }
126
127    // Find WebView's proxy BroadcastReceiver and prompt it to read proxy system properties.
128    private void setWebViewProxy() {
129        LoadedApk loadedApk = getApplication().mLoadedApk;
130        try {
131            Field receiversField = LoadedApk.class.getDeclaredField("mReceivers");
132            receiversField.setAccessible(true);
133            ArrayMap receivers = (ArrayMap) receiversField.get(loadedApk);
134            for (Object receiverMap : receivers.values()) {
135                for (Object rec : ((ArrayMap) receiverMap).keySet()) {
136                    Class clazz = rec.getClass();
137                    if (clazz.getName().contains("ProxyChangeListener")) {
138                        Method onReceiveMethod = clazz.getDeclaredMethod("onReceive", Context.class,
139                                Intent.class);
140                        Intent intent = new Intent(Proxy.PROXY_CHANGE_ACTION);
141                        onReceiveMethod.invoke(rec, getApplicationContext(), intent);
142                        Log.v(TAG, "Prompting WebView proxy reload.");
143                    }
144                }
145            }
146        } catch (Exception e) {
147            Log.e(TAG, "Exception while setting WebView proxy: " + e);
148        }
149    }
150
151    private void done(Result result) {
152        if (mNetworkCallback != null) {
153            mCm.unregisterNetworkCallback(mNetworkCallback);
154            mNetworkCallback = null;
155        }
156        switch (result) {
157            case DISMISSED:
158                mCaptivePortal.reportCaptivePortalDismissed();
159                break;
160            case UNWANTED:
161                mCaptivePortal.ignoreNetwork();
162                break;
163            case WANTED_AS_IS:
164                mCaptivePortal.useNetwork();
165                break;
166        }
167        finishAndRemoveTask();
168    }
169
170    @Override
171    public boolean onCreateOptionsMenu(Menu menu) {
172        getMenuInflater().inflate(R.menu.captive_portal_login, menu);
173        return true;
174    }
175
176    @Override
177    public void onBackPressed() {
178        WebView myWebView = (WebView) findViewById(R.id.webview);
179        if (myWebView.canGoBack() && mWebViewClient.allowBack()) {
180            myWebView.goBack();
181        } else {
182            super.onBackPressed();
183        }
184    }
185
186    @Override
187    public boolean onOptionsItemSelected(MenuItem item) {
188        int id = item.getItemId();
189        if (id == R.id.action_use_network) {
190            done(Result.WANTED_AS_IS);
191            return true;
192        }
193        if (id == R.id.action_do_not_use_network) {
194            done(Result.UNWANTED);
195            return true;
196        }
197        return super.onOptionsItemSelected(item);
198    }
199
200    @Override
201    public void onDestroy() {
202        super.onDestroy();
203
204        if (mNetworkCallback != null) {
205            mCm.unregisterNetworkCallback(mNetworkCallback);
206            mNetworkCallback = null;
207        }
208        if (mLaunchBrowser) {
209            // Give time for this network to become default. After 500ms just proceed.
210            for (int i = 0; i < 5; i++) {
211                // TODO: This misses when mNetwork underlies a VPN.
212                if (mNetwork.equals(mCm.getActiveNetwork())) break;
213                try {
214                    Thread.sleep(100);
215                } catch (InterruptedException e) {
216                }
217            }
218            startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse(mURL.toString())));
219        }
220    }
221
222    private void testForCaptivePortal() {
223        new Thread(new Runnable() {
224            public void run() {
225                // Give time for captive portal to open.
226                try {
227                    Thread.sleep(1000);
228                } catch (InterruptedException e) {
229                }
230                HttpURLConnection urlConnection = null;
231                int httpResponseCode = 500;
232                try {
233                    urlConnection = (HttpURLConnection) mURL.openConnection();
234                    urlConnection.setInstanceFollowRedirects(false);
235                    urlConnection.setConnectTimeout(SOCKET_TIMEOUT_MS);
236                    urlConnection.setReadTimeout(SOCKET_TIMEOUT_MS);
237                    urlConnection.setUseCaches(false);
238                    urlConnection.getInputStream();
239                    httpResponseCode = urlConnection.getResponseCode();
240                } catch (IOException e) {
241                } finally {
242                    if (urlConnection != null) urlConnection.disconnect();
243                }
244                if (httpResponseCode == 204) {
245                    done(Result.DISMISSED);
246                }
247            }
248        }).start();
249    }
250
251    private class MyWebViewClient extends WebViewClient {
252        private static final String INTERNAL_ASSETS = "file:///android_asset/";
253        private final String mBrowserBailOutToken = Long.toString(new Random().nextLong());
254        // How many Android device-independent-pixels per scaled-pixel
255        // dp/sp = (px/sp) / (px/dp) = (1/sp) / (1/dp)
256        private final float mDpPerSp = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, 1,
257                    getResources().getDisplayMetrics()) /
258                    TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 1,
259                    getResources().getDisplayMetrics());
260        private int mPagesLoaded;
261
262        // If we haven't finished cleaning up the history, don't allow going back.
263        public boolean allowBack() {
264            return mPagesLoaded > 1;
265        }
266
267        @Override
268        public void onPageStarted(WebView view, String url, Bitmap favicon) {
269            if (url.contains(mBrowserBailOutToken)) {
270                mLaunchBrowser = true;
271                done(Result.WANTED_AS_IS);
272                return;
273            }
274            // The first page load is used only to cause the WebView to
275            // fetch the proxy settings.  Don't update the URL bar, and
276            // don't check if the captive portal is still there.
277            if (mPagesLoaded == 0) return;
278            // For internally generated pages, leave URL bar listing prior URL as this is the URL
279            // the page refers to.
280            if (!url.startsWith(INTERNAL_ASSETS)) {
281                final TextView myUrlBar = (TextView) findViewById(R.id.url_bar);
282                myUrlBar.setText(url);
283            }
284            testForCaptivePortal();
285        }
286
287        @Override
288        public void onPageFinished(WebView view, String url) {
289            mPagesLoaded++;
290            if (mPagesLoaded == 1) {
291                // Now that WebView has loaded at least one page we know it has read in the proxy
292                // settings.  Now prompt the WebView read the Network-specific proxy settings.
293                setWebViewProxy();
294                // Load the real page.
295                view.loadUrl(mURL.toString());
296                return;
297            } else if (mPagesLoaded == 2) {
298                // Prevent going back to empty first page.
299                view.clearHistory();
300            }
301            testForCaptivePortal();
302        }
303
304        // Convert Android device-independent-pixels (dp) to HTML size.
305        private String dp(int dp) {
306            // HTML px's are scaled just like dp's, so just add "px" suffix.
307            return Integer.toString(dp) + "px";
308        }
309
310        // Convert Android scaled-pixels (sp) to HTML size.
311        private String sp(int sp) {
312            // Convert sp to dp's.
313            float dp = sp * mDpPerSp;
314            // Apply a scale factor to make things look right.
315            dp *= 1.3;
316            // Convert dp's to HTML size.
317            return dp((int)dp);
318        }
319
320        // A web page consisting of a large broken lock icon to indicate SSL failure.
321        private final String SSL_ERROR_HTML = "<html><head><style>" +
322                "body { margin-left:" + dp(48) + "; margin-right:" + dp(48) + "; " +
323                        "margin-top:" + dp(96) + "; background-color:#fafafa; }" +
324                "img { width:" + dp(48) + "; height:" + dp(48) + "; }" +
325                "div.warn { font-size:" + sp(16) + "; margin-top:" + dp(16) + "; " +
326                "           opacity:0.87; line-height:1.28; }" +
327                "div.example { font-size:" + sp(14) + "; margin-top:" + dp(16) + "; " +
328                "              opacity:0.54; line-height:1.21905; }" +
329                "a { font-size:" + sp(14) + "; text-decoration:none; text-transform:uppercase; " +
330                "    margin-top:" + dp(24) + "; display:inline-block; color:#4285F4; " +
331                "    height:" + dp(48) + "; font-weight:bold; }" +
332                "</style></head><body><p><img src=quantum_ic_warning_amber_96.png><br>" +
333                "<div class=warn>%s</div>" +
334                "<div class=example>%s</div>" +
335                "<a href=%s>%s</a></body></html>";
336
337        @Override
338        public void onReceivedSslError(WebView view, SslErrorHandler handler, SslError error) {
339            Log.w(TAG, "SSL error (error: " + error.getPrimaryError() + " host: " +
340                    // Only show host to avoid leaking private info.
341                    Uri.parse(error.getUrl()).getHost() + " certificate: " +
342                    error.getCertificate() + "); displaying SSL warning.");
343            final String html = String.format(SSL_ERROR_HTML, getString(R.string.ssl_error_warning),
344                    getString(R.string.ssl_error_example), mBrowserBailOutToken,
345                    getString(R.string.ssl_error_continue));
346            view.loadDataWithBaseURL(INTERNAL_ASSETS, html, "text/HTML", "UTF-8", null);
347        }
348
349        @Override
350        public boolean shouldOverrideUrlLoading (WebView view, String url) {
351            if (url.startsWith("tel:")) {
352                startActivity(new Intent(Intent.ACTION_DIAL, Uri.parse(url)));
353                return true;
354            }
355            return false;
356        }
357    }
358
359    private class MyWebChromeClient extends WebChromeClient {
360        @Override
361        public void onProgressChanged(WebView view, int newProgress) {
362            final ProgressBar myProgressBar = (ProgressBar) findViewById(R.id.progress_bar);
363            myProgressBar.setProgress(newProgress);
364        }
365    }
366}
367