| 1 | // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | package org.chromium.android_webview; |
| 6 | |
| 7 | import android.content.Context; |
| 8 | import android.content.res.AssetManager; |
| 9 | import android.net.Uri; |
| 10 | import android.util.Log; |
| 11 | import android.util.TypedValue; |
| 12 | |
| 13 | import java.io.InputStream; |
| 14 | import java.io.IOException; |
| 15 | import java.net.URLConnection; |
| 16 | import java.util.List; |
| 17 | |
| 18 | import org.chromium.base.CalledByNativeUnchecked; |
| 19 | import org.chromium.base.JNINamespace; |
| 20 | |
| 21 | /** |
| 22 | * Implements the Java side of Android URL protocol jobs. |
| 23 | * See android_protocol_handler.cc. |
| 24 | */ |
| 25 | @JNINamespace("android_webview") |
| 26 | public class AndroidProtocolHandler { |
| 27 | private static final String TAG = "AndroidProtocolHandler"; |
| 28 | |
| 29 | // Supported URL schemes. This needs to be kept in sync with |
| 30 | // clank/native/framework/chrome/url_request_android_job.cc. |
| 31 | private static final String FILE_SCHEME = "file"; |
| 32 | private static final String CONTENT_SCHEME = "content"; |
| 33 | |
| 34 | /** |
| 35 | * Open an InputStream for an Android resource. |
| 36 | * @param context The context manager. |
| 37 | * @param url The url to load. |
| 38 | * @return An InputStream to the Android resource. |
| 39 | */ |
| 40 | // TODO(bulach): this should have either a throw clause, or |
| 41 | // handle the exception in the java side rather than the native side. |
| 42 | @CalledByNativeUnchecked |
| 43 | public static InputStream open(Context context, String url) { |
| 44 | Uri uri = verifyUrl(url); |
| 45 | if (uri == null) { |
| 46 | return null; |
| 47 | } |
| 48 | String path = uri.getPath(); |
| 49 | if (uri.getScheme().equals(FILE_SCHEME)) { |
| 50 | if (path.startsWith(nativeGetAndroidAssetPath())) { |
| 51 | return openAsset(context, uri); |
| 52 | } else if (path.startsWith(nativeGetAndroidResourcePath())) { |
| 53 | return openResource(context, uri); |
| 54 | } |
| 55 | } else if (uri.getScheme().equals(CONTENT_SCHEME)) { |
| 56 | return openContent(context, uri); |
| 57 | } |
| 58 | return null; |
| 59 | } |
| 60 | |
| 61 | private static int getFieldId(Context context, String assetType, String assetName) |
| 62 | throws ClassNotFoundException, NoSuchFieldException, IllegalAccessException { |
| 63 | Class<?> d = context.getClassLoader() |
| 64 | .loadClass(context.getPackageName() + ".R$" + assetType); |
| 65 | java.lang.reflect.Field field = d.getField(assetName); |
| 66 | int id = field.getInt(null); |
| 67 | return id; |
| 68 | } |
| 69 | |
| 70 | private static int getValueType(Context context, int field_id) { |
| 71 | TypedValue value = new TypedValue(); |
| 72 | context.getResources().getValue(field_id, value, true); |
| 73 | return value.type; |
| 74 | } |
| 75 | |
| 76 | private static InputStream openResource(Context context, Uri uri) { |
| 77 | assert(uri.getScheme().equals(FILE_SCHEME)); |
| 78 | assert(uri.getPath() != null); |
| 79 | assert(uri.getPath().startsWith(nativeGetAndroidResourcePath())); |
| 80 | // The path must be of the form "/android_res/asset_type/asset_name.ext". |
| 81 | List<String> pathSegments = uri.getPathSegments(); |
| 82 | if (pathSegments.size() != 3) { |
| 83 | Log.e(TAG, "Incorrect resource path: " + uri); |
| 84 | return null; |
| 85 | } |
| 86 | String assetPath = pathSegments.get(0); |
| 87 | String assetType = pathSegments.get(1); |
| 88 | String assetName = pathSegments.get(2); |
| 89 | if (!("/" + assetPath + "/").equals(nativeGetAndroidResourcePath())) { |
| 90 | Log.e(TAG, "Resource path does not start with " + nativeGetAndroidResourcePath() + |
| 91 | ": " + uri); |
| 92 | return null; |
| 93 | } |
| 94 | // Drop the file extension. |
| 95 | assetName = assetName.split("\\.")[0]; |
| 96 | try { |
| 97 | // Use the application context for resolving the resource package name so that we do |
| 98 | // not use the browser's own resources. Note that if 'context' here belongs to the |
| 99 | // test suite, it does not have a separate application context. In that case we use |
| 100 | // the original context object directly. |
| 101 | if (context.getApplicationContext() != null) { |
| 102 | context = context.getApplicationContext(); |
| 103 | } |
| 104 | int field_id = getFieldId(context, assetType, assetName); |
| 105 | int value_type = getValueType(context, field_id); |
| 106 | if (value_type == TypedValue.TYPE_STRING) { |
| 107 | return context.getResources().openRawResource(field_id); |
| 108 | } else { |
| 109 | Log.e(TAG, "Asset not of type string: " + uri); |
| 110 | return null; |
| 111 | } |
| 112 | } catch (ClassNotFoundException e) { |
| 113 | Log.e(TAG, "Unable to open resource URL: " + uri, e); |
| 114 | return null; |
| 115 | } catch (NoSuchFieldException e) { |
| 116 | Log.e(TAG, "Unable to open resource URL: " + uri, e); |
| 117 | return null; |
| 118 | } catch (IllegalAccessException e) { |
| 119 | Log.e(TAG, "Unable to open resource URL: " + uri, e); |
| 120 | return null; |
| 121 | } |
| 122 | } |
| 123 | |
| 124 | private static InputStream openAsset(Context context, Uri uri) { |
| 125 | assert(uri.getScheme().equals(FILE_SCHEME)); |
| 126 | assert(uri.getPath() != null); |
| 127 | assert(uri.getPath().startsWith(nativeGetAndroidAssetPath())); |
| 128 | String path = uri.getPath().replaceFirst(nativeGetAndroidAssetPath(), ""); |
| 129 | try { |
| 130 | AssetManager assets = context.getAssets(); |
| 131 | return assets.open(path, AssetManager.ACCESS_STREAMING); |
| 132 | } catch (IOException e) { |
| 133 | Log.e(TAG, "Unable to open asset URL: " + uri); |
| 134 | return null; |
| 135 | } |
| 136 | } |
| 137 | |
| 138 | private static InputStream openContent(Context context, Uri uri) { |
| 139 | assert(uri.getScheme().equals(CONTENT_SCHEME)); |
| 140 | try { |
| 141 | // We strip the query parameters before opening the stream to |
| 142 | // ensure that the URL we try to load exactly matches the URL |
| 143 | // we have permission to read. |
| 144 | Uri baseUri = stripQueryParameters(uri); |
| 145 | return context.getContentResolver().openInputStream(baseUri); |
| 146 | } catch (Exception e) { |
| 147 | Log.e(TAG, "Unable to open content URL: " + uri); |
| 148 | return null; |
| 149 | } |
| 150 | } |
| 151 | |
| 152 | /** |
| 153 | * Determine the mime type for an Android resource. |
| 154 | * @param context The context manager. |
| 155 | * @param stream The opened input stream which to examine. |
| 156 | * @param url The url from which the stream was opened. |
| 157 | * @return The mime type or null if the type is unknown. |
| 158 | */ |
| 159 | // TODO(bulach): this should have either a throw clause, or |
| 160 | // handle the exception in the java side rather than the native side. |
| 161 | @CalledByNativeUnchecked |
| 162 | public static String getMimeType(Context context, InputStream stream, String url) { |
| 163 | Uri uri = verifyUrl(url); |
| 164 | if (uri == null) { |
| 165 | return null; |
| 166 | } |
| 167 | String path = uri.getPath(); |
| 168 | // The content URL type can be queried directly. |
| 169 | if (uri.getScheme().equals(CONTENT_SCHEME)) { |
| 170 | return context.getContentResolver().getType(uri); |
| 171 | // Asset files may have a known extension. |
| 172 | } else if (uri.getScheme().equals(FILE_SCHEME) && |
| 173 | path.startsWith(nativeGetAndroidAssetPath())) { |
| 174 | String mimeType = URLConnection.guessContentTypeFromName(path); |
| 175 | if (mimeType != null) { |
| 176 | return mimeType; |
| 177 | } |
| 178 | } |
| 179 | // Fall back to sniffing the type from the stream. |
| 180 | try { |
| 181 | return URLConnection.guessContentTypeFromStream(stream); |
| 182 | } catch (IOException e) { |
| 183 | return null; |
| 184 | } |
| 185 | } |
| 186 | |
| 187 | /** |
| 188 | * Make sure the given string URL is correctly formed and parse it into a Uri. |
| 189 | * @return a Uri instance, or null if the URL was invalid. |
| 190 | */ |
| 191 | private static Uri verifyUrl(String url) { |
| 192 | if (url == null) { |
| 193 | return null; |
| 194 | } |
| 195 | Uri uri = Uri.parse(url); |
| 196 | if (uri == null) { |
| 197 | Log.e(TAG, "Malformed URL: " + url); |
| 198 | return null; |
| 199 | } |
| 200 | String path = uri.getPath(); |
| 201 | if (path == null || path.length() == 0) { |
| 202 | Log.e(TAG, "URL does not have a path: " + url); |
| 203 | return null; |
| 204 | } |
| 205 | return uri; |
| 206 | } |
| 207 | |
| 208 | /** |
| 209 | * Remove query parameters from a Uri. |
| 210 | * @param uri The input uri. |
| 211 | * @return The given uri without query parameters. |
| 212 | */ |
| 213 | private static Uri stripQueryParameters(Uri uri) { |
| 214 | assert(uri.getAuthority() != null); |
| 215 | assert(uri.getPath() != null); |
| 216 | Uri.Builder builder = new Uri.Builder(); |
| 217 | builder.scheme(uri.getScheme()); |
| 218 | builder.encodedAuthority(uri.getAuthority()); |
| 219 | builder.encodedPath(uri.getPath()); |
| 220 | return builder.build(); |
| 221 | } |
| 222 | |
| 223 | /** |
| 224 | * Set the context to be used for resolving resource queries. |
| 225 | * @param context Context to be used, or null for the default application |
| 226 | * context. |
| 227 | */ |
| 228 | public static void setResourceContextForTesting(Context context) { |
| 229 | nativeSetResourceContextForTesting(context); |
| 230 | } |
| 231 | |
| 232 | private static native void nativeSetResourceContextForTesting(Context context); |
| 233 | private static native String nativeGetAndroidAssetPath(); |
| 234 | private static native String nativeGetAndroidResourcePath(); |
| 235 | } |