app/src/main/java/com/stoutner/privacybrowser/dialogs/SslCertificateErrorDialog.java

   1 /*
   2  * Copyright © 2016-2019 Soren Stoutner <soren@stoutner.com>.
   3  *
   4  * This file is part of Privacy Browser <https://www.stoutner.com/privacy-browser>.
   5  *
   6  * Privacy Browser is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation, either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * Privacy Browser is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with Privacy Browser.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 package com.stoutner.privacybrowser.dialogs;
  21
  22 import android.annotation.SuppressLint;
  23 import android.app.Activity;
  24 import android.app.AlertDialog;
  25 import android.app.Dialog;
  26 import android.content.Context;
  27 import android.content.DialogInterface;
  28 import android.net.Uri;
  29 import android.net.http.SslCertificate;
  30 import android.net.http.SslError;
  31 import android.os.AsyncTask;
  32 import android.os.Bundle;
  33 import android.text.SpannableStringBuilder;
  34 import android.text.Spanned;
  35 import android.text.style.ForegroundColorSpan;
  36 import android.view.LayoutInflater;
  37 import android.view.WindowManager;
  38 import android.widget.TextView;
  39
  40 import androidx.annotation.NonNull;
  41 import androidx.fragment.app.DialogFragment;  // The AndroidX dialog fragment must be used or an error is produced on API <=22.
  42
  43 import com.stoutner.privacybrowser.R;
  44 import com.stoutner.privacybrowser.activities.MainWebViewActivity;
  45
  46 import java.lang.ref.WeakReference;
  47 import java.net.InetAddress;
  48 import java.net.UnknownHostException;
  49 import java.text.DateFormat;
  50 import java.util.Date;
  51
  52 public class SslCertificateErrorDialog extends DialogFragment {
  53     // `sslCertificateErrorListener` is used in `onAttach` and `onCreateDialog`.
  54     private SslCertificateErrorListener sslCertificateErrorListener;
  55
  56     // The public interface is used to send information back to the parent activity.
  57     public interface SslCertificateErrorListener {
  58         void onSslErrorCancel();
  59
  60         void onSslErrorProceed();
  61     }
  62
  63     public void onAttach(Context context) {
  64         // Run the default commands.
  65         super.onAttach(context);
  66
  67         // Get a handle for `SslCertificateErrorListener` from the launching context.
  68         sslCertificateErrorListener = (SslCertificateErrorListener) context;
  69     }
  70
  71     public static SslCertificateErrorDialog displayDialog(SslError error) {
  72         // Get the various components of the SSL error message.
  73         int primaryErrorIntForBundle = error.getPrimaryError();
  74         String urlWithErrorForBundle = error.getUrl();
  75         SslCertificate sslCertificate = error.getCertificate();
  76         String issuedToCNameForBundle = sslCertificate.getIssuedTo().getCName();
  77         String issuedToONameForBundle = sslCertificate.getIssuedTo().getOName();
  78         String issuedToUNameForBundle = sslCertificate.getIssuedTo().getUName();
  79         String issuedByCNameForBundle = sslCertificate.getIssuedBy().getCName();
  80         String issuedByONameForBundle = sslCertificate.getIssuedBy().getOName();
  81         String issuedByUNameForBundle = sslCertificate.getIssuedBy().getUName();
  82         Date startDateForBundle = sslCertificate.getValidNotBeforeDate();
  83         Date endDateForBundle = sslCertificate.getValidNotAfterDate();
  84
  85         // Store the SSL error message components in a `Bundle`.
  86         Bundle argumentsBundle = new Bundle();
  87         argumentsBundle.putInt("PrimaryErrorInt", primaryErrorIntForBundle);
  88         argumentsBundle.putString("UrlWithError", urlWithErrorForBundle);
  89         argumentsBundle.putString("IssuedToCName", issuedToCNameForBundle);
  90         argumentsBundle.putString("IssuedToOName", issuedToONameForBundle);
  91         argumentsBundle.putString("IssuedToUName", issuedToUNameForBundle);
  92         argumentsBundle.putString("IssuedByCName", issuedByCNameForBundle);
  93         argumentsBundle.putString("IssuedByOName", issuedByONameForBundle);
  94         argumentsBundle.putString("IssuedByUName", issuedByUNameForBundle);
  95         argumentsBundle.putString("StartDate", DateFormat.getDateTimeInstance(DateFormat.MEDIUM, DateFormat.LONG).format(startDateForBundle));
  96         argumentsBundle.putString("EndDate", DateFormat.getDateTimeInstance(DateFormat.MEDIUM, DateFormat.LONG).format(endDateForBundle));
  97
  98         // Add `argumentsBundle` to this instance of `SslCertificateErrorDialog`.
  99         SslCertificateErrorDialog thisSslCertificateErrorDialog = new SslCertificateErrorDialog();
 100         thisSslCertificateErrorDialog.setArguments(argumentsBundle);
 101         return thisSslCertificateErrorDialog;
 102     }
 103
 104     // `@SuppressLing("InflateParams")` removes the warning about using `null` as the parent view group when inflating the `AlertDialog`.
 105     @SuppressLint("InflateParams")
 106     @SuppressWarnings("deprecation")
 107     @Override
 108     @NonNull
 109     public Dialog onCreateDialog(Bundle savedInstanceState) {
 110         // Remove the incorrect lint warning that `getArguments()` might be null.
 111         assert getArguments() != null;
 112
 113         // Get the components of the SSL error message from the bundle.
 114         int primaryErrorInt = getArguments().getInt("PrimaryErrorInt");
 115         String urlWithErrors = getArguments().getString("UrlWithError");
 116         String issuedToCName = getArguments().getString("IssuedToCName");
 117         String issuedToOName = getArguments().getString("IssuedToOName");
 118         String issuedToUName = getArguments().getString("IssuedToUName");
 119         String issuedByCName = getArguments().getString("IssuedByCName");
 120         String issuedByOName = getArguments().getString("IssuedByOName");
 121         String issuedByUName = getArguments().getString("IssuedByUName");
 122         String startDate = getArguments().getString("StartDate");
 123         String endDate = getArguments().getString("EndDate");
 124
 125         // Remove the incorrect lint warning that `getActivity()` might be null.
 126         assert getActivity() != null;
 127
 128         // Get the activity's layout inflater.
 129         LayoutInflater layoutInflater = getActivity().getLayoutInflater();
 130
 131         // Use an alert dialog builder to create the alert dialog.
 132         AlertDialog.Builder dialogBuilder;
 133
 134         // Set the style and icon according to the theme.
 135         if (MainWebViewActivity.darkTheme) {
 136             // Set the style.
 137             dialogBuilder = new AlertDialog.Builder(getActivity(), R.style.PrivacyBrowserAlertDialogDark);
 138
 139             // Set the icon.
 140             dialogBuilder.setIcon(R.drawable.ssl_certificate_enabled_dark);
 141         } else {
 142             // Set the style.
 143             dialogBuilder = new AlertDialog.Builder(getActivity(), R.style.PrivacyBrowserAlertDialogLight);
 144
 145             // Set the icon.
 146             dialogBuilder.setIcon(R.drawable.ssl_certificate_enabled_light);
 147         }
 148
 149         // Set the title.
 150         dialogBuilder.setTitle(R.string.ssl_certificate_error);
 151
 152         // Set the view.  The parent view is `null` because it will be assigned by `AlertDialog`.
 153         dialogBuilder.setView(layoutInflater.inflate(R.layout.ssl_certificate_error, null));
 154
 155         // Set a listener on the negative button.
 156         dialogBuilder.setNegativeButton(R.string.cancel, (DialogInterface dialog, int which) -> sslCertificateErrorListener.onSslErrorCancel());
 157
 158         // Set a listener on the positive button.
 159         dialogBuilder.setPositiveButton(R.string.proceed, (DialogInterface dialog, int which) -> sslCertificateErrorListener.onSslErrorProceed());
 160
 161
 162         // Create an alert dialog from the alert dialog builder.
 163         AlertDialog alertDialog = dialogBuilder.create();
 164
 165         // Disable screenshots if not allowed.
 166         if (!MainWebViewActivity.allowScreenshots) {
 167             // Remove the warning below that `getWindow()` might be null.
 168             assert alertDialog.getWindow() != null;
 169
 170             // Disable screenshots.
 171             alertDialog.getWindow().addFlags(WindowManager.LayoutParams.FLAG_SECURE);
 172         }
 173
 174         // Get a URI for the URL with errors.
 175         Uri uriWithErrors = Uri.parse(urlWithErrors);
 176
 177         // Get the IP addresses for the URI.
 178         new GetIpAddresses(getActivity(), alertDialog).execute(uriWithErrors.getHost());
 179
 180         // The alert dialog must be shown before the contents can be modified.
 181         alertDialog.show();
 182
 183         // Get handles for the `TextViews`
 184         TextView primaryErrorTextView = alertDialog.findViewById(R.id.primary_error);
 185         TextView urlTextView = alertDialog.findViewById(R.id.url);
 186         TextView issuedToCNameTextView = alertDialog.findViewById(R.id.issued_to_cname);
 187         TextView issuedToONameTextView = alertDialog.findViewById(R.id.issued_to_oname);
 188         TextView issuedToUNameTextView = alertDialog.findViewById(R.id.issued_to_uname);
 189         TextView issuedByTextView = alertDialog.findViewById(R.id.issued_by_textview);
 190         TextView issuedByCNameTextView = alertDialog.findViewById(R.id.issued_by_cname);
 191         TextView issuedByONameTextView = alertDialog.findViewById(R.id.issued_by_oname);
 192         TextView issuedByUNameTextView = alertDialog.findViewById(R.id.issued_by_uname);
 193         TextView validDatesTextView = alertDialog.findViewById(R.id.valid_dates_textview);
 194         TextView startDateTextView = alertDialog.findViewById(R.id.start_date);
 195         TextView endDateTextView = alertDialog.findViewById(R.id.end_date);
 196
 197         // Setup the common strings.
 198         String urlLabel = getString(R.string.url_label) + "  ";
 199         String cNameLabel = getString(R.string.common_name) + "  ";
 200         String oNameLabel = getString(R.string.organization) + "  ";
 201         String uNameLabel = getString(R.string.organizational_unit) + "  ";
 202         String startDateLabel = getString(R.string.start_date) + "  ";
 203         String endDateLabel = getString(R.string.end_date) + "  ";
 204
 205         // Create a spannable string builder for each text view that needs multiple colors of text.
 206         SpannableStringBuilder urlStringBuilder = new SpannableStringBuilder(urlLabel + urlWithErrors);
 207         SpannableStringBuilder issuedToCNameStringBuilder = new SpannableStringBuilder(cNameLabel + issuedToCName);
 208         SpannableStringBuilder issuedToONameStringBuilder = new SpannableStringBuilder(oNameLabel + issuedToOName);
 209         SpannableStringBuilder issuedToUNameStringBuilder = new SpannableStringBuilder(uNameLabel + issuedToUName);
 210         SpannableStringBuilder issuedByCNameStringBuilder = new SpannableStringBuilder(cNameLabel + issuedByCName);
 211         SpannableStringBuilder issuedByONameStringBuilder = new SpannableStringBuilder(oNameLabel + issuedByOName);
 212         SpannableStringBuilder issuedByUNameStringBuilder = new SpannableStringBuilder(uNameLabel + issuedByUName);
 213         SpannableStringBuilder startDateStringBuilder = new SpannableStringBuilder(startDateLabel + startDate);
 214         SpannableStringBuilder endDateStringBuilder = new SpannableStringBuilder((endDateLabel + endDate));
 215
 216         // Create a red foreground color span.  The deprecated `getResources().getColor` must be used until the minimum API >= 23.
 217         @SuppressWarnings("deprecation") ForegroundColorSpan redColorSpan = new ForegroundColorSpan(getResources().getColor(R.color.red_a700));
 218
 219         // Create a blue `ForegroundColorSpan`.
 220         ForegroundColorSpan blueColorSpan;
 221
 222         // Set a blue color span according to the theme.  The deprecated `getResources().getColor` must be used until the minimum API >= 23.
 223         if (MainWebViewActivity.darkTheme) {
 224             //noinspection deprecation
 225             blueColorSpan = new ForegroundColorSpan(getResources().getColor(R.color.blue_400));
 226         } else {
 227             //noinspection deprecation
 228             blueColorSpan = new ForegroundColorSpan(getResources().getColor(R.color.blue_700));
 229         }
 230
 231         // Setup the spans to display the certificate information in blue.  `SPAN_INCLUSIVE_INCLUSIVE` allows the span to grow in either direction.
 232         urlStringBuilder.setSpan(blueColorSpan, urlLabel.length(), urlStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 233         issuedToCNameStringBuilder.setSpan(blueColorSpan, cNameLabel.length(), issuedToCNameStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 234         issuedToONameStringBuilder.setSpan(blueColorSpan, oNameLabel.length(), issuedToONameStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 235         issuedToUNameStringBuilder.setSpan(blueColorSpan, uNameLabel.length(), issuedToUNameStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 236         issuedByCNameStringBuilder.setSpan(blueColorSpan, cNameLabel.length(), issuedByCNameStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 237         issuedByONameStringBuilder.setSpan(blueColorSpan, oNameLabel.length(), issuedByONameStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 238         issuedByUNameStringBuilder.setSpan(blueColorSpan, uNameLabel.length(), issuedByUNameStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 239         startDateStringBuilder.setSpan(blueColorSpan, startDateLabel.length(), startDateStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 240         endDateStringBuilder.setSpan(blueColorSpan, endDateLabel.length(), endDateStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 241
 242         // Initialize `primaryErrorString`.
 243         String primaryErrorString = "";
 244
 245         // Highlight the primary error in red and store the primary error string in `primaryErrorString`.
 246         switch (primaryErrorInt) {
 247             case SslError.SSL_IDMISMATCH:
 248                 // Change the URL span colors to red.
 249                 urlStringBuilder.setSpan(redColorSpan, urlLabel.length(), urlStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 250                 issuedToCNameStringBuilder.setSpan(redColorSpan, cNameLabel.length(), issuedToCNameStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 251
 252                 // Store the primary error string.
 253                 primaryErrorString = getString(R.string.cn_mismatch);
 254                 break;
 255
 256             case SslError.SSL_UNTRUSTED:
 257                 // Change the issued by text view text to red.  The deprecated `getResources().getColor` must be used until the minimum API >= 23.
 258                 issuedByTextView.setTextColor(getResources().getColor(R.color.red_a700));
 259
 260                 // Change the issued by span color to red.
 261                 issuedByCNameStringBuilder.setSpan(redColorSpan, cNameLabel.length(), issuedByCNameStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 262                 issuedByONameStringBuilder.setSpan(redColorSpan, oNameLabel.length(), issuedByONameStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 263                 issuedByUNameStringBuilder.setSpan(redColorSpan, uNameLabel.length(), issuedByUNameStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 264
 265                 // Store the primary error string.
 266                 primaryErrorString = getString(R.string.untrusted);
 267                 break;
 268
 269             case SslError.SSL_DATE_INVALID:
 270                 // Change the valid dates text view text to red.  The deprecated `getResources().getColor` must be used until the minimum API >= 23.
 271                 validDatesTextView.setTextColor(getResources().getColor(R.color.red_a700));
 272
 273                 // Change the date span colors to red.
 274                 startDateStringBuilder.setSpan(redColorSpan, startDateLabel.length(), startDateStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 275                 endDateStringBuilder.setSpan(redColorSpan, endDateLabel.length(), endDateStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 276
 277                 // Store the primary error string.
 278                 primaryErrorString = getString(R.string.invalid_date);
 279                 break;
 280
 281             case SslError.SSL_NOTYETVALID:
 282                 // Change the start date span color to red.
 283                 startDateStringBuilder.setSpan(redColorSpan, startDateLabel.length(), startDateStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 284
 285                 // Store the primary error string.
 286                 primaryErrorString = getString(R.string.future_certificate);
 287                 break;
 288
 289             case SslError.SSL_EXPIRED:
 290                 // Change the end date span color to red.
 291                 endDateStringBuilder.setSpan(redColorSpan, endDateLabel.length(), endDateStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 292
 293                 // Store the primary error string.
 294                 primaryErrorString = getString(R.string.expired_certificate);
 295                 break;
 296
 297             case SslError.SSL_INVALID:
 298                 // Store the primary error string.
 299                 primaryErrorString = getString(R.string.invalid_certificate);
 300                 break;
 301         }
 302
 303
 304         // Display the strings.
 305         primaryErrorTextView.setText(primaryErrorString);
 306         urlTextView.setText(urlStringBuilder);
 307         issuedToCNameTextView.setText(issuedToCNameStringBuilder);
 308         issuedToONameTextView.setText(issuedToONameStringBuilder);
 309         issuedToUNameTextView.setText(issuedToUNameStringBuilder);
 310         issuedByCNameTextView.setText(issuedByCNameStringBuilder);
 311         issuedByONameTextView.setText(issuedByONameStringBuilder);
 312         issuedByUNameTextView.setText(issuedByUNameStringBuilder);
 313         startDateTextView.setText(startDateStringBuilder);
 314         endDateTextView.setText(endDateStringBuilder);
 315
 316         // `onCreateDialog` requires the return of an alert dialog.
 317         return alertDialog;
 318     }
 319
 320
 321     // This must run asynchronously because it involves a network request.  `String` declares the parameters.  `Void` does not declare progress units.  `SpannableStringBuilder` contains the results.
 322     private static class GetIpAddresses extends AsyncTask<String, Void, SpannableStringBuilder> {
 323         // The weak references are used to determine if the activity or the alert dialog have disappeared while the AsyncTask is running.
 324         private WeakReference<Activity> activityWeakReference;
 325         private WeakReference<AlertDialog> alertDialogWeakReference;
 326
 327         GetIpAddresses(Activity activity, AlertDialog alertDialog) {
 328             // Populate the weak references.
 329             activityWeakReference = new WeakReference<>(activity);
 330             alertDialogWeakReference = new WeakReference<>(alertDialog);
 331         }
 332
 333         @Override
 334         protected SpannableStringBuilder doInBackground(String... domainName) {
 335             // Get handles for the activity and the alert dialog.
 336             Activity activity = activityWeakReference.get();
 337             AlertDialog alertDialog = alertDialogWeakReference.get();
 338
 339             // Abort if the activity or the dialog is gone.
 340             if ((activity == null) || (activity.isFinishing()) || (alertDialog == null)) {
 341                 return new SpannableStringBuilder();
 342             }
 343
 344             // Initialize an IP address string builder.
 345             StringBuilder ipAddresses = new StringBuilder();
 346
 347             // Get an array with the IP addresses for the host.
 348             try {
 349                 // Get an array with all the IP addresses for the domain.
 350                 InetAddress[] inetAddressesArray = InetAddress.getAllByName(domainName[0]);
 351
 352                 // Add each IP address to the string builder.
 353                 for (InetAddress inetAddress : inetAddressesArray) {
 354                     if (ipAddresses.length() == 0) {  // This is the first IP address.
 355                         // Add the IP Address to the string builder.
 356                         ipAddresses.append(inetAddress.getHostAddress());
 357                     } else {  // This is not the first IP address.
 358                         // Add a line break to the string builder first.
 359                         ipAddresses.append("\n");
 360
 361                         // Add the IP address to the string builder.
 362                         ipAddresses.append(inetAddress.getHostAddress());
 363                     }
 364                 }
 365             } catch (UnknownHostException exception) {
 366                 // Do nothing.
 367             }
 368
 369             // Set the label.
 370             String ipAddressesLabel = activity.getString(R.string.ip_addresses) + "  ";
 371
 372             // Create a spannable string builder.
 373             SpannableStringBuilder ipAddressesStringBuilder = new SpannableStringBuilder(ipAddressesLabel + ipAddresses);
 374
 375             // Create a blue foreground color span.
 376             ForegroundColorSpan blueColorSpan;
 377
 378             // Set the blue color span according to the theme.  The deprecated `getColor()` must be used until the minimum API >= 23.
 379             if (MainWebViewActivity.darkTheme) {
 380                 //noinspection deprecation
 381                 blueColorSpan = new ForegroundColorSpan(activity.getResources().getColor(R.color.blue_400));
 382             } else {
 383                 //noinspection deprecation
 384                 blueColorSpan = new ForegroundColorSpan(activity.getResources().getColor(R.color.blue_700));
 385             }
 386
 387             // Set the string builder to display the certificate information in blue.  `SPAN_INCLUSIVE_INCLUSIVE` allows the span to grow in either direction.
 388             ipAddressesStringBuilder.setSpan(blueColorSpan, ipAddressesLabel.length(), ipAddressesStringBuilder.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
 389
 390             // Return the formatted string.
 391             return ipAddressesStringBuilder;
 392         }
 393
 394         // `onPostExecute()` operates on the UI thread.
 395         @Override
 396         protected void onPostExecute(SpannableStringBuilder ipAddresses) {
 397             // Get handles for the activity and the alert dialog.
 398             Activity activity = activityWeakReference.get();
 399             AlertDialog alertDialog = alertDialogWeakReference.get();
 400
 401             // Abort if the activity or the alert dialog is gone.
 402             if ((activity == null) || (activity.isFinishing()) || (alertDialog == null)) {
 403                 return;
 404             }
 405
 406             // Get a handle for the IP addresses text view.
 407             TextView ipAddressesTextView = alertDialog.findViewById(R.id.ip_addresses);
 408
 409             // Populate the IP addresses text view.
 410             ipAddressesTextView.setText(ipAddresses);
 411         }
 412     }
 413 }