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      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
    329