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            finish();
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        mWebViewClient = new MyWebViewClient();
119        myWebView.setWebViewClient(mWebViewClient);
120        myWebView.setWebChromeClient(new MyWebChromeClient());
121        // Start initial page load so WebView finishes loading proxy settings.
122        // Actual load of mUrl is initiated by MyWebViewClient.
123        myWebView.loadData("", "text/html", null);
124    }
125
126    // Find WebView's proxy BroadcastReceiver and prompt it to read proxy system properties.
127    private void setWebViewProxy() {
128        LoadedApk loadedApk = getApplication().mLoadedApk;
129        try {
130            Field receiversField = LoadedApk.class.getDeclaredField("mReceivers");
131            receiversField.setAccessible(true);
132            ArrayMap receivers = (ArrayMap) receiversField.get(loadedApk);
133            for (Object receiverMap : receivers.values()) {
134                for (Object rec : ((ArrayMap) receiverMap).keySet()) {
135                    Class clazz = rec.getClass();
136                    if (clazz.getName().contains("ProxyChangeListener")) {
137                        Method onReceiveMethod = clazz.getDeclaredMethod("onReceive", Context.class,
138                                Intent.class);
139                        Intent intent = new Intent(Proxy.PROXY_CHANGE_ACTION);
140                        onReceiveMethod.invoke(rec, getApplicationContext(), intent);
141                        Log.v(TAG, "Prompting WebView proxy reload.");
142                    }
143                }
144            }
145        } catch (Exception e) {
146            Log.e(TAG, "Exception while setting WebView proxy: " + e);
147        }
148    }
149
150    private void done(Result result) {
151        if (mNetworkCallback != null) {
152            mCm.unregisterNetworkCallback(mNetworkCallback);
153            mNetworkCallback = null;
154        }
155        switch (result) {
156            case DISMISSED:
157                mCaptivePortal.reportCaptivePortalDismissed();
158                break;
159            case UNWANTED:
160                mCaptivePortal.ignoreNetwork();
161                break;
162            case WANTED_AS_IS:
163                mCaptivePortal.useNetwork();
164                break;
165        }
166        finish();
167    }
168
169    @Override
170    public boolean onCreateOptionsMenu(Menu menu) {
171        getMenuInflater().inflate(R.menu.captive_portal_login, menu);
172        return true;
173    }
174
175    @Override
176    public void onBackPressed() {
177        WebView myWebView = (WebView) findViewById(R.id.webview);
178        if (myWebView.canGoBack() && mWebViewClient.allowBack()) {
179            myWebView.goBack();
180        } else {
181            super.onBackPressed();
182        }
183    }
184
185    @Override
186    public boolean onOptionsItemSelected(MenuItem item) {
187        int id = item.getItemId();
188        if (id == R.id.action_use_network) {
189            done(Result.WANTED_AS_IS);
190            return true;
191        }
192        if (id == R.id.action_do_not_use_network) {
193            done(Result.UNWANTED);
194            return true;
195        }
196        return super.onOptionsItemSelected(item);
197    }
198
199    @Override
200    public void onDestroy() {
201        super.onDestroy();
202
203        if (mNetworkCallback != null) {
204            mCm.unregisterNetworkCallback(mNetworkCallback);
205            mNetworkCallback = null;
206        }
207        if (mLaunchBrowser) {
208            // Give time for this network to become default. After 500ms just proceed.
209            for (int i = 0; i < 5; i++) {
210                // TODO: This misses when mNetwork underlies a VPN.
211                if (mNetwork.equals(mCm.getActiveNetwork())) break;
212                try {
213                    Thread.sleep(100);
214                } catch (InterruptedException e) {
215                }
216            }
217            startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse(mURL.toString())));
218        }
219    }
220
221    private void testForCaptivePortal() {
222        new Thread(new Runnable() {
223            public void run() {
224                // Give time for captive portal to open.
225                try {
226                    Thread.sleep(1000);
227                } catch (InterruptedException e) {
228                }
229                HttpURLConnection urlConnection = null;
230                int httpResponseCode = 500;
231                try {
232                    urlConnection = (HttpURLConnection) mURL.openConnection();
233                    urlConnection.setInstanceFollowRedirects(false);
234                    urlConnection.setConnectTimeout(SOCKET_TIMEOUT_MS);
235                    urlConnection.setReadTimeout(SOCKET_TIMEOUT_MS);
236                    urlConnection.setUseCaches(false);
237                    urlConnection.getInputStream();
238                    httpResponseCode = urlConnection.getResponseCode();
239                } catch (IOException e) {
240                } finally {
241                    if (urlConnection != null) urlConnection.disconnect();
242                }
243                if (httpResponseCode == 204) {
244                    done(Result.DISMISSED);
245                }
246            }
247        }).start();
248    }
249
250    private class MyWebViewClient extends WebViewClient {
251        private static final String INTERNAL_ASSETS = "file:///android_asset/";
252        private final String mBrowserBailOutToken = Long.toString(new Random().nextLong());
253        // How many Android device-independent-pixels per scaled-pixel
254        // dp/sp = (px/sp) / (px/dp) = (1/sp) / (1/dp)
255        private final float mDpPerSp = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, 1,
256                    getResources().getDisplayMetrics()) /
257                    TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 1,
258                    getResources().getDisplayMetrics());
259        private int mPagesLoaded;
260
261        // If we haven't finished cleaning up the history, don't allow going back.
262        public boolean allowBack() {
263            return mPagesLoaded > 1;
264        }
265
266        @Override
267        public void onPageStarted(WebView view, String url, Bitmap favicon) {
268            if (url.contains(mBrowserBailOutToken)) {
269                mLaunchBrowser = true;
270                done(Result.WANTED_AS_IS);
271                return;
272            }
273            // The first page load is used only to cause the WebView to
274            // fetch the proxy settings.  Don't update the URL bar, and
275            // don't check if the captive portal is still there.
276            if (mPagesLoaded == 0) return;
277            // For internally generated pages, leave URL bar listing prior URL as this is the URL
278            // the page refers to.
279            if (!url.startsWith(INTERNAL_ASSETS)) {
280                final TextView myUrlBar = (TextView) findViewById(R.id.url_bar);
281                myUrlBar.setText(url);
282            }
283            testForCaptivePortal();
284        }
285
286        @Override
287        public void onPageFinished(WebView view, String url) {
288            mPagesLoaded++;
289            if (mPagesLoaded == 1) {
290                // Now that WebView has loaded at least one page we know it has read in the proxy
291                // settings.  Now prompt the WebView read the Network-specific proxy settings.
292                setWebViewProxy();
293                // Load the real page.
294                view.loadUrl(mURL.toString());
295                return;
296            } else if (mPagesLoaded == 2) {
297                // Prevent going back to empty first page.
298                view.clearHistory();
299            }
300            testForCaptivePortal();
301        }
302
303        // Convert Android device-independent-pixels (dp) to HTML size.
304        private String dp(int dp) {
305            // HTML px's are scaled just like dp's, so just add "px" suffix.
306            return Integer.toString(dp) + "px";
307        }
308
309        // Convert Android scaled-pixels (sp) to HTML size.
310        private String sp(int sp) {
311            // Convert sp to dp's.
312            float dp = sp * mDpPerSp;
313            // Apply a scale factor to make things look right.
314            dp *= 1.3;
315            // Convert dp's to HTML size.
316            return dp((int)dp);
317        }
318
319        // A web page consisting of a large broken lock icon to indicate SSL failure.
320        private final String SSL_ERROR_HTML = "<html><head><style>" +
321                "body { margin-left:" + dp(48) + "; margin-right:" + dp(48) + "; " +
322                        "margin-top:" + dp(96) + "; background-color:#fafafa; }" +
323                "img { width:" + dp(48) + "; height:" + dp(48) + "; }" +
324                "div.warn { font-size:" + sp(16) + "; margin-top:" + dp(16) + "; " +
325                "           opacity:0.87; line-height:1.28; }" +
326                "div.example { font-size:" + sp(14) + "; margin-top:" + dp(16) + "; " +
327                "              opacity:0.54; line-height:1.21905; }" +
328                "a { font-size:" + sp(14) + "; text-decoration:none; text-transform:uppercase; " +
329                "    margin-top:" + dp(24) + "; display:inline-block; color:#4285F4; " +
330                "    height:" + dp(48) + "; font-weight:bold; }" +
331                "</style></head><body><p><img src=quantum_ic_warning_amber_96.png><br>" +
332                "<div class=warn>%s</div>" +
333                "<div class=example>%s</div>" +
334                "<a href=%s>%s</a></body></html>";
335
336        @Override
337        public void onReceivedSslError(WebView view, SslErrorHandler handler, SslError error) {
338            Log.w(TAG, "SSL error (error: " + error.getPrimaryError() + " host: " +
339                    // Only show host to avoid leaking private info.
340                    Uri.parse(error.getUrl()).getHost() + " certificate: " +
341                    error.getCertificate() + "); displaying SSL warning.");
342            final String html = String.format(SSL_ERROR_HTML, getString(R.string.ssl_error_warning),
343                    getString(R.string.ssl_error_example), mBrowserBailOutToken,
344                    getString(R.string.ssl_error_continue));
345            view.loadDataWithBaseURL(INTERNAL_ASSETS, html, "text/HTML", "UTF-8", null);
346        }
347
348        @Override
349        public boolean shouldOverrideUrlLoading (WebView view, String url) {
350            if (url.startsWith("tel:")) {
351                startActivity(new Intent(Intent.ACTION_DIAL, Uri.parse(url)));
352                return true;
353            }
354            return false;
355        }
356    }
357
358    private class MyWebChromeClient extends WebChromeClient {
359        @Override
360        public void onProgressChanged(WebView view, int newProgress) {
361            final ProgressBar myProgressBar = (ProgressBar) findViewById(R.id.progress_bar);
362            myProgressBar.setProgress(newProgress);
363        }
364    }
365}
366