1 files changed, 120 insertions, 0 deletions
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/IntentUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/IntentUtils.java
new file mode 100644
index 0000000000..20a7b95f4d
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/IntentUtils.java
@@ -0,0 +1,120 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+package org.mozilla.gecko.util;
+
+import android.annotation.TargetApi;
+import android.content.Intent;
+import android.net.Uri;
+import java.net.URISyntaxException;
+import java.util.Locale;
+
+/** Utilities for Intents. */
+public class IntentUtils {
+  private IntentUtils() {}
+
+  /**
+   * Return a Uri instance which is equivalent to uri, but with a guaranteed-lowercase scheme as if
+   * the API level 16 method Uri.normalizeScheme had been called.
+   *
+   * @param uri The URI string to normalize.
+   * @return The corresponding normalized Uri.
+   */
+  private static Uri normalizeUriScheme(final Uri uri) {
+    final String scheme = uri.getScheme();
+    if (scheme == null) {
+      return uri;
+    }
+    final String lower = scheme.toLowerCase(Locale.ROOT);
+    if (lower.equals(scheme)) {
+      return uri;
+    }
+
+    // Otherwise, return a new URI with a normalized scheme.
+    return uri.buildUpon().scheme(lower).build();
+  }
+
+  /**
+   * Return a normalized Uri instance that corresponds to the given URI string with cross-API-level
+   * compatibility.
+   *
+   * @param aUri The URI string to normalize.
+   * @return The corresponding normalized Uri.
+   */
+  public static Uri normalizeUri(final String aUri) {
+    final Uri normUri =
+        normalizeUriScheme(
+            aUri.indexOf(':') >= 0 ? Uri.parse(aUri) : new Uri.Builder().scheme(aUri).build());
+    return normUri;
+  }
+
+  public static boolean isUriSafeForScheme(final String aUri) {
+    return isUriSafeForScheme(normalizeUri(aUri));
+  }
+
+  /**
+   * Verify whether the given URI is considered safe to load in respect to its scheme. Unsafe URIs
+   * should be blocked from further handling.
+   *
+   * @param aUri The URI instance to test.
+   * @return Whether the provided URI is considered safe in respect to its scheme.
+   */
+  public static boolean isUriSafeForScheme(final Uri aUri) {
+    final String scheme = aUri.getScheme();
+    if ("tel".equals(scheme) || "sms".equals(scheme)) {
+      // Bug 794034 - We don't want to pass MWI or USSD codes to the
+      // dialer, and ensure the Uri class doesn't parse a URI
+      // containing a fragment ('#')
+      final String number = aUri.getSchemeSpecificPart();
+      if (number.contains("#") || number.contains("*") || aUri.getFragment() != null) {
+        return false;
+      }
+    }
+
+    if (("intent".equals(scheme) || "android-app".equals(scheme))) {
+      // Bug 1356893 - Rject intents with file data schemes.
+      return getSafeIntent(aUri) != null;
+    }
+
+    return true;
+  }
+
+  /**
+   * Create a safe intent for the given URI. Intents with file data schemes are considered unsafe.
+   *
+   * @param aUri The URI for the intent.
+   * @return A safe intent for the given URI or null if URI is considered unsafe.
+   */
+  public static Intent getSafeIntent(final Uri aUri) {
+    final Intent intent;
+    try {
+      intent = Intent.parseUri(aUri.toString(), 0);
+    } catch (final URISyntaxException e) {
+      return null;
+    }
+
+    final Uri data = intent.getData();
+    if (data != null && "file".equals(normalizeUriScheme(data).getScheme())) {
+      return null;
+    }
+
+    // Only open applications which can accept arbitrary data from a browser.
+    intent.addCategory(Intent.CATEGORY_BROWSABLE);
+
+    // Prevent site from explicitly opening our internal activities,
+    // which can leak data.
+    intent.setComponent(null);
+    nullIntentSelector(intent);
+
+    return intent;
+  }
+
+  // We create a separate method to better encapsulate the @TargetApi use.
+  @TargetApi(15)
+  private static void nullIntentSelector(final Intent intent) {
+    intent.setSelector(null);
+  }
+}