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