Home | History | Annotate | Download | only in extensions 
      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/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.h"
     22 #include "chrome/common/extensions/extension_file_util.h"
     23 #include "chrome/common/extensions/extension_l10n_util.h"
     24 #include "chrome/common/extensions/extension_manifest_constants.h"
     25 #include "chrome/common/extensions/manifest.h"
     26 #include "content/public/child/image_decoder_utils.h"
     27 #include "content/public/common/common_param_traits.h"
     28 #include "extensions/common/constants.h"
     29 #include "grit/generated_resources.h"
     30 #include "ipc/ipc_message_utils.h"
     31 #include "net/base/file_stream.h"
     32 #include "third_party/skia/include/core/SkBitmap.h"
     33 #include "third_party/zlib/google/zip.h"
     34 #include "ui/base/l10n/l10n_util.h"
     35 #include "ui/gfx/size.h"
     36 
     37 namespace errors = extension_manifest_errors;
     38 namespace keys = extension_manifest_keys;
     39 
     40 namespace {
     41 
     42 // A limit to stop us passing dangerously large canvases to the browser.
     43 const int kMaxImageCanvas = 4096 * 4096;
     44 
     45 SkBitmap DecodeImage(const base::FilePath& path) {
     46   // Read the file from disk.
     47   std::string file_contents;
     48   if (!base::PathExists(path) ||
     49       !file_util::ReadFileToString(path, &file_contents)) {
     50     return SkBitmap();
     51   }
     52 
     53   // Decode the image using WebKit's image decoder.
     54   const unsigned char* data =
     55       reinterpret_cast<const unsigned char*>(file_contents.data());
     56   SkBitmap bitmap = content::DecodeImage(data,
     57                                          gfx::Size(),
     58                                          file_contents.length());
     59   Sk64 bitmap_size = bitmap.getSize64();
     60   if (!bitmap_size.is32() || bitmap_size.get32() > kMaxImageCanvas)
     61     return SkBitmap();
     62   return bitmap;
     63 }
     64 
     65 bool PathContainsParentDirectory(const base::FilePath& path) {
     66   const base::FilePath::StringType kSeparators(base::FilePath::kSeparators);
     67   const base::FilePath::StringType kParentDirectory(
     68       base::FilePath::kParentDirectory);
     69   const size_t npos = base::FilePath::StringType::npos;
     70   const base::FilePath::StringType& value = path.value();
     71 
     72   for (size_t i = 0; i < value.length(); ) {
     73     i = value.find(kParentDirectory, i);
     74     if (i != npos) {
     75       if ((i == 0 || kSeparators.find(value[i-1]) == npos) &&
     76           (i+1 < value.length() || kSeparators.find(value[i+1]) == npos)) {
     77         return true;
     78       }
     79       ++i;
     80     }
     81   }
     82 
     83   return false;
     84 }
     85 
     86 }  // namespace
     87 
     88 namespace extensions {
     89 
     90 struct Unpacker::InternalData {
     91   DecodedImages decoded_images;
     92 };
     93 
     94 Unpacker::Unpacker(const base::FilePath& extension_path,
     95                    const std::string& extension_id,
     96                    Manifest::Location location,
     97                    int creation_flags)
     98     : extension_path_(extension_path),
     99       extension_id_(extension_id),
    100       location_(location),
    101       creation_flags_(creation_flags) {
    102   internal_data_.reset(new InternalData());
    103 }
    104 
    105 Unpacker::~Unpacker() {
    106 }
    107 
    108 base::DictionaryValue* Unpacker::ReadManifest() {
    109   base::FilePath manifest_path =
    110       temp_install_dir_.Append(kManifestFilename);
    111   if (!base::PathExists(manifest_path)) {
    112     SetError(errors::kInvalidManifest);
    113     return NULL;
    114   }
    115 
    116   JSONFileValueSerializer serializer(manifest_path);
    117   std::string error;
    118   scoped_ptr<base::Value> root(serializer.Deserialize(NULL, &error));
    119   if (!root.get()) {
    120     SetError(error);
    121     return NULL;
    122   }
    123 
    124   if (!root->IsType(base::Value::TYPE_DICTIONARY)) {
    125     SetError(errors::kInvalidManifest);
    126     return NULL;
    127   }
    128 
    129   return static_cast<base::DictionaryValue*>(root.release());
    130 }
    131 
    132 bool Unpacker::ReadAllMessageCatalogs(const std::string& default_locale) {
    133   base::FilePath locales_path =
    134     temp_install_dir_.Append(kLocaleFolder);
    135 
    136   // Not all folders under _locales have to be valid locales.
    137   base::FileEnumerator locales(locales_path,
    138                                false,
    139                                base::FileEnumerator::DIRECTORIES);
    140 
    141   std::set<std::string> all_locales;
    142   extension_l10n_util::GetAllLocales(&all_locales);
    143   base::FilePath locale_path;
    144   while (!(locale_path = locales.Next()).empty()) {
    145     if (extension_l10n_util::ShouldSkipValidation(locales_path, locale_path,
    146                                                   all_locales))
    147       continue;
    148 
    149     base::FilePath messages_path = locale_path.Append(kMessagesFilename);
    150 
    151     if (!ReadMessageCatalog(messages_path))
    152       return false;
    153   }
    154 
    155   return true;
    156 }
    157 
    158 bool Unpacker::Run() {
    159   DVLOG(1) << "Installing extension " << extension_path_.value();
    160 
    161   // <profile>/Extensions/CRX_INSTALL
    162   temp_install_dir_ =
    163       extension_path_.DirName().AppendASCII(kTempExtensionName);
    164 
    165   if (!file_util::CreateDirectory(temp_install_dir_)) {
    166     SetUTF16Error(
    167         l10n_util::GetStringFUTF16(
    168             IDS_EXTENSION_PACKAGE_DIRECTORY_ERROR,
    169             base::i18n::GetDisplayStringInLTRDirectionality(
    170                 temp_install_dir_.LossyDisplayName())));
    171     return false;
    172   }
    173 
    174   if (!zip::Unzip(extension_path_, temp_install_dir_)) {
    175     SetUTF16Error(l10n_util::GetStringUTF16(IDS_EXTENSION_PACKAGE_UNZIP_ERROR));
    176     return false;
    177   }
    178 
    179   // Parse the manifest.
    180   parsed_manifest_.reset(ReadManifest());
    181   if (!parsed_manifest_.get())
    182     return false;  // Error was already reported.
    183 
    184   std::string error;
    185   scoped_refptr<Extension> extension(Extension::Create(
    186       temp_install_dir_,
    187       location_,
    188       *parsed_manifest_,
    189       creation_flags_,
    190       extension_id_,
    191       &error));
    192   if (!extension.get()) {
    193     SetError(error);
    194     return false;
    195   }
    196 
    197   std::vector<InstallWarning> warnings;
    198   if (!extension_file_util::ValidateExtension(extension.get(),
    199                                               &error, &warnings)) {
    200     SetError(error);
    201     return false;
    202   }
    203   extension->AddInstallWarnings(warnings);
    204 
    205   // Decode any images that the browser needs to display.
    206   std::set<base::FilePath> image_paths =
    207       extension_file_util::GetBrowserImagePaths(extension.get());
    208   for (std::set<base::FilePath>::iterator it = image_paths.begin();
    209        it != image_paths.end();
    210        ++it) {
    211     if (!AddDecodedImage(*it))
    212       return false;  // Error was already reported.
    213   }
    214 
    215   // Parse all message catalogs (if any).
    216   parsed_catalogs_.reset(new base::DictionaryValue);
    217   if (!LocaleInfo::GetDefaultLocale(extension.get()).empty()) {
    218     if (!ReadAllMessageCatalogs(LocaleInfo::GetDefaultLocale(extension.get())))
    219       return false;  // Error was already reported.
    220   }
    221 
    222   return true;
    223 }
    224 
    225 bool Unpacker::DumpImagesToFile() {
    226   IPC::Message pickle;  // We use a Message so we can use WriteParam.
    227   IPC::WriteParam(&pickle, internal_data_->decoded_images);
    228 
    229   base::FilePath path = extension_path_.DirName().AppendASCII(
    230       kDecodedImagesFilename);
    231   if (!file_util::WriteFile(path, static_cast<const char*>(pickle.data()),
    232                             pickle.size())) {
    233     SetError("Could not write image data to disk.");
    234     return false;
    235   }
    236 
    237   return true;
    238 }
    239 
    240 bool Unpacker::DumpMessageCatalogsToFile() {
    241   IPC::Message pickle;
    242   IPC::WriteParam(&pickle, *parsed_catalogs_.get());
    243 
    244   base::FilePath path = extension_path_.DirName().AppendASCII(
    245       kDecodedMessageCatalogsFilename);
    246   if (!file_util::WriteFile(path, static_cast<const char*>(pickle.data()),
    247                             pickle.size())) {
    248     SetError("Could not write message catalogs to disk.");
    249     return false;
    250   }
    251 
    252   return true;
    253 }
    254 
    255 bool Unpacker::AddDecodedImage(const base::FilePath& path) {
    256   // Make sure it's not referencing a file outside the extension's subdir.
    257   if (path.IsAbsolute() || PathContainsParentDirectory(path)) {
    258     SetUTF16Error(
    259         l10n_util::GetStringFUTF16(
    260             IDS_EXTENSION_PACKAGE_IMAGE_PATH_ERROR,
    261             base::i18n::GetDisplayStringInLTRDirectionality(
    262                 path.LossyDisplayName())));
    263     return false;
    264   }
    265 
    266   SkBitmap image_bitmap = DecodeImage(temp_install_dir_.Append(path));
    267   if (image_bitmap.isNull()) {
    268     SetUTF16Error(
    269         l10n_util::GetStringFUTF16(
    270             IDS_EXTENSION_PACKAGE_IMAGE_ERROR,
    271             base::i18n::GetDisplayStringInLTRDirectionality(
    272                 path.BaseName().LossyDisplayName())));
    273     return false;
    274   }
    275 
    276   internal_data_->decoded_images.push_back(MakeTuple(image_bitmap, path));
    277   return true;
    278 }
    279 
    280 bool Unpacker::ReadMessageCatalog(const base::FilePath& message_path) {
    281   std::string error;
    282   JSONFileValueSerializer serializer(message_path);
    283   scoped_ptr<base::DictionaryValue> root(static_cast<base::DictionaryValue*>(
    284       serializer.Deserialize(NULL, &error)));
    285   if (!root.get()) {
    286     string16 messages_file = message_path.LossyDisplayName();
    287     if (error.empty()) {
    288       // If file is missing, Deserialize will fail with empty error.
    289       SetError(base::StringPrintf("%s %s", errors::kLocalesMessagesFileMissing,
    290                                   UTF16ToUTF8(messages_file).c_str()));
    291     } else {
    292       SetError(base::StringPrintf("%s: %s",
    293                                   UTF16ToUTF8(messages_file).c_str(),
    294                                   error.c_str()));
    295     }
    296     return false;
    297   }
    298 
    299   base::FilePath relative_path;
    300   // message_path was created from temp_install_dir. This should never fail.
    301   if (!temp_install_dir_.AppendRelativePath(message_path, &relative_path)) {
    302     NOTREACHED();
    303     return false;
    304   }
    305 
    306   std::string dir_name = relative_path.DirName().MaybeAsASCII();
    307   if (dir_name.empty()) {
    308     NOTREACHED();
    309     return false;
    310   }
    311   parsed_catalogs_->Set(dir_name, root.release());
    312 
    313   return true;
    314 }
    315 
    316 void Unpacker::SetError(const std::string &error) {
    317   SetUTF16Error(UTF8ToUTF16(error));
    318 }
    319 
    320 void Unpacker::SetUTF16Error(const string16 &error) {
    321   error_message_ = error;
    322 }
    323 
    324 }  // namespace extensions
    325