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