src/chrome/utility/extensions/unpacker.cc

   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 #include "chrome/utility/extensions/unpacker.h"
   6
   7 #include <set>
   8
   9 #include "base/file_util.h"
  10 #include "base/files/file_enumerator.h"
  11 #include "base/files/scoped_temp_dir.h"
  12 #include "base/i18n/rtl.h"
  13 #include "base/json/json_file_value_serializer.h"
  14 #include "base/memory/scoped_handle.h"
  15 #include "base/numerics/safe_conversions.h"
  16 #include "base/strings/string_util.h"
  17 #include "base/strings/utf_string_conversions.h"
  18 #include "base/threading/thread.h"
  19 #include "base/values.h"
  20 #include "chrome/common/chrome_utility_messages.h"
  21 #include "chrome/common/extensions/api/i18n/default_locale_handler.h"
  22 #include "chrome/common/extensions/extension_file_util.h"
  23 #include "content/public/child/image_decoder_utils.h"
  24 #include "content/public/common/common_param_traits.h"
  25 #include "extensions/common/constants.h"
  26 #include "extensions/common/extension.h"
  27 #include "extensions/common/extension_l10n_util.h"
  28 #include "extensions/common/file_util.h"
  29 #include "extensions/common/manifest.h"
  30 #include "extensions/common/manifest_constants.h"
  31 #include "grit/generated_resources.h"
  32 #include "ipc/ipc_message_utils.h"
  33 #include "net/base/file_stream.h"
  34 #include "third_party/skia/include/core/SkBitmap.h"
  35 #include "third_party/zlib/google/zip.h"
  36 #include "ui/base/l10n/l10n_util.h"
  37 #include "ui/gfx/size.h"
  38
  39 namespace extensions {
  40
  41 namespace {
  42
  43 namespace errors = manifest_errors;
  44 namespace keys = manifest_keys;
  45
  46 // A limit to stop us passing dangerously large canvases to the browser.
  47 const int kMaxImageCanvas = 4096 * 4096;
  48
  49 SkBitmap DecodeImage(const base::FilePath& path) {
  50   // Read the file from disk.
  51   std::string file_contents;
  52   if (!base::PathExists(path) ||
  53       !base::ReadFileToString(path, &file_contents)) {
  54     return SkBitmap();
  55   }
  56
  57   // Decode the image using WebKit's image decoder.
  58   const unsigned char* data =
  59       reinterpret_cast<const unsigned char*>(file_contents.data());
  60   SkBitmap bitmap = content::DecodeImage(data,
  61                                          gfx::Size(),
  62                                          file_contents.length());
  63   if (bitmap.computeSize64() > kMaxImageCanvas)
  64     return SkBitmap();
  65   return bitmap;
  66 }
  67
  68 bool PathContainsParentDirectory(const base::FilePath& path) {
  69   const base::FilePath::StringType kSeparators(base::FilePath::kSeparators);
  70   const base::FilePath::StringType kParentDirectory(
  71       base::FilePath::kParentDirectory);
  72   const size_t npos = base::FilePath::StringType::npos;
  73   const base::FilePath::StringType& value = path.value();
  74
  75   for (size_t i = 0; i < value.length(); ) {
  76     i = value.find(kParentDirectory, i);
  77     if (i != npos) {
  78       if ((i == 0 || kSeparators.find(value[i-1]) == npos) &&
  79           (i+1 < value.length() || kSeparators.find(value[i+1]) == npos)) {
  80         return true;
  81       }
  82       ++i;
  83     }
  84   }
  85
  86   return false;
  87 }
  88
  89 bool WritePickle(const IPC::Message& pickle, const base::FilePath& dest_path) {
  90   int size = base::checked_cast<int>(pickle.size());
  91   const char* data = static_cast<const char*>(pickle.data());
  92   int bytes_written = base::WriteFile(dest_path, data, size);
  93   return (bytes_written == size);
  94 }
  95
  96 }  // namespace
  97
  98 struct Unpacker::InternalData {
  99   DecodedImages decoded_images;
 100 };
 101
 102 Unpacker::Unpacker(const base::FilePath& extension_path,
 103                    const std::string& extension_id,
 104                    Manifest::Location location,
 105                    int creation_flags)
 106     : extension_path_(extension_path),
 107       extension_id_(extension_id),
 108       location_(location),
 109       creation_flags_(creation_flags) {
 110   internal_data_.reset(new InternalData());
 111 }
 112
 113 Unpacker::~Unpacker() {
 114 }
 115
 116 base::DictionaryValue* Unpacker::ReadManifest() {
 117   base::FilePath manifest_path =
 118       temp_install_dir_.Append(kManifestFilename);
 119   if (!base::PathExists(manifest_path)) {
 120     SetError(errors::kInvalidManifest);
 121     return NULL;
 122   }
 123
 124   JSONFileValueSerializer serializer(manifest_path);
 125   std::string error;
 126   scoped_ptr<base::Value> root(serializer.Deserialize(NULL, &error));
 127   if (!root.get()) {
 128     SetError(error);
 129     return NULL;
 130   }
 131
 132   if (!root->IsType(base::Value::TYPE_DICTIONARY)) {
 133     SetError(errors::kInvalidManifest);
 134     return NULL;
 135   }
 136
 137   return static_cast<base::DictionaryValue*>(root.release());
 138 }
 139
 140 bool Unpacker::ReadAllMessageCatalogs(const std::string& default_locale) {
 141   base::FilePath locales_path =
 142     temp_install_dir_.Append(kLocaleFolder);
 143
 144   // Not all folders under _locales have to be valid locales.
 145   base::FileEnumerator locales(locales_path,
 146                                false,
 147                                base::FileEnumerator::DIRECTORIES);
 148
 149   std::set<std::string> all_locales;
 150   extension_l10n_util::GetAllLocales(&all_locales);
 151   base::FilePath locale_path;
 152   while (!(locale_path = locales.Next()).empty()) {
 153     if (extension_l10n_util::ShouldSkipValidation(locales_path, locale_path,
 154                                                   all_locales))
 155       continue;
 156
 157     base::FilePath messages_path = locale_path.Append(kMessagesFilename);
 158
 159     if (!ReadMessageCatalog(messages_path))
 160       return false;
 161   }
 162
 163   return true;
 164 }
 165
 166 bool Unpacker::Run() {
 167   DVLOG(1) << "Installing extension " << extension_path_.value();
 168
 169   // <profile>/Extensions/CRX_INSTALL
 170   temp_install_dir_ =
 171       extension_path_.DirName().AppendASCII(kTempExtensionName);
 172
 173   if (!base::CreateDirectory(temp_install_dir_)) {
 174     SetUTF16Error(
 175         l10n_util::GetStringFUTF16(
 176             IDS_EXTENSION_PACKAGE_DIRECTORY_ERROR,
 177             base::i18n::GetDisplayStringInLTRDirectionality(
 178                 temp_install_dir_.LossyDisplayName())));
 179     return false;
 180   }
 181
 182   if (!zip::Unzip(extension_path_, temp_install_dir_)) {
 183     SetUTF16Error(l10n_util::GetStringUTF16(IDS_EXTENSION_PACKAGE_UNZIP_ERROR));
 184     return false;
 185   }
 186
 187   // Parse the manifest.
 188   parsed_manifest_.reset(ReadManifest());
 189   if (!parsed_manifest_.get())
 190     return false;  // Error was already reported.
 191
 192   std::string error;
 193   scoped_refptr<Extension> extension(Extension::Create(
 194       temp_install_dir_,
 195       location_,
 196       *parsed_manifest_,
 197       creation_flags_,
 198       extension_id_,
 199       &error));
 200   if (!extension.get()) {
 201     SetError(error);
 202     return false;
 203   }
 204
 205   std::vector<InstallWarning> warnings;
 206   if (!file_util::ValidateExtension(extension.get(), &error, &warnings)) {
 207     SetError(error);
 208     return false;
 209   }
 210   extension->AddInstallWarnings(warnings);
 211
 212   // Decode any images that the browser needs to display.
 213   std::set<base::FilePath> image_paths =
 214       extension_file_util::GetBrowserImagePaths(extension.get());
 215   for (std::set<base::FilePath>::iterator it = image_paths.begin();
 216        it != image_paths.end();
 217        ++it) {
 218     if (!AddDecodedImage(*it))
 219       return false;  // Error was already reported.
 220   }
 221
 222   // Parse all message catalogs (if any).
 223   parsed_catalogs_.reset(new base::DictionaryValue);
 224   if (!LocaleInfo::GetDefaultLocale(extension.get()).empty()) {
 225     if (!ReadAllMessageCatalogs(LocaleInfo::GetDefaultLocale(extension.get())))
 226       return false;  // Error was already reported.
 227   }
 228
 229   return true;
 230 }
 231
 232 bool Unpacker::DumpImagesToFile() {
 233   IPC::Message pickle;  // We use a Message so we can use WriteParam.
 234   IPC::WriteParam(&pickle, internal_data_->decoded_images);
 235
 236   base::FilePath path = extension_path_.DirName().AppendASCII(
 237       kDecodedImagesFilename);
 238   if (!WritePickle(pickle, path)) {
 239     SetError("Could not write image data to disk.");
 240     return false;
 241   }
 242
 243   return true;
 244 }
 245
 246 bool Unpacker::DumpMessageCatalogsToFile() {
 247   IPC::Message pickle;
 248   IPC::WriteParam(&pickle, *parsed_catalogs_.get());
 249
 250   base::FilePath path = extension_path_.DirName().AppendASCII(
 251       kDecodedMessageCatalogsFilename);
 252   if (!WritePickle(pickle, path)) {
 253     SetError("Could not write message catalogs to disk.");
 254     return false;
 255   }
 256
 257   return true;
 258 }
 259
 260 bool Unpacker::AddDecodedImage(const base::FilePath& path) {
 261   // Make sure it's not referencing a file outside the extension's subdir.
 262   if (path.IsAbsolute() || PathContainsParentDirectory(path)) {
 263     SetUTF16Error(
 264         l10n_util::GetStringFUTF16(
 265             IDS_EXTENSION_PACKAGE_IMAGE_PATH_ERROR,
 266             base::i18n::GetDisplayStringInLTRDirectionality(
 267                 path.LossyDisplayName())));
 268     return false;
 269   }
 270
 271   SkBitmap image_bitmap = DecodeImage(temp_install_dir_.Append(path));
 272   if (image_bitmap.isNull()) {
 273     SetUTF16Error(
 274         l10n_util::GetStringFUTF16(
 275             IDS_EXTENSION_PACKAGE_IMAGE_ERROR,
 276             base::i18n::GetDisplayStringInLTRDirectionality(
 277                 path.BaseName().LossyDisplayName())));
 278     return false;
 279   }
 280
 281   internal_data_->decoded_images.push_back(MakeTuple(image_bitmap, path));
 282   return true;
 283 }
 284
 285 bool Unpacker::ReadMessageCatalog(const base::FilePath& message_path) {
 286   std::string error;
 287   JSONFileValueSerializer serializer(message_path);
 288   scoped_ptr<base::DictionaryValue> root(static_cast<base::DictionaryValue*>(
 289       serializer.Deserialize(NULL, &error)));
 290   if (!root.get()) {
 291     base::string16 messages_file = message_path.LossyDisplayName();
 292     if (error.empty()) {
 293       // If file is missing, Deserialize will fail with empty error.
 294       SetError(base::StringPrintf("%s %s", errors::kLocalesMessagesFileMissing,
 295                                   base::UTF16ToUTF8(messages_file).c_str()));
 296     } else {
 297       SetError(base::StringPrintf("%s: %s",
 298                                   base::UTF16ToUTF8(messages_file).c_str(),
 299                                   error.c_str()));
 300     }
 301     return false;
 302   }
 303
 304   base::FilePath relative_path;
 305   // message_path was created from temp_install_dir. This should never fail.
 306   if (!temp_install_dir_.AppendRelativePath(message_path, &relative_path)) {
 307     NOTREACHED();
 308     return false;
 309   }
 310
 311   std::string dir_name = relative_path.DirName().MaybeAsASCII();
 312   if (dir_name.empty()) {
 313     NOTREACHED();
 314     return false;
 315   }
 316   parsed_catalogs_->Set(dir_name, root.release());
 317
 318   return true;
 319 }
 320
 321 void Unpacker::SetError(const std::string &error) {
 322   SetUTF16Error(base::UTF8ToUTF16(error));
 323 }
 324
 325 void Unpacker::SetUTF16Error(const base::string16& error) {
 326   error_message_ = error;
 327 }
 328
 329 }  // namespace extensions