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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/browser/extensions/webstore_installer.h"
      6 
      7 #include <vector>
      8 
      9 #include "base/basictypes.h"
     10 #include "base/bind.h"
     11 #include "base/command_line.h"
     12 #include "base/files/file_util.h"
     13 #include "base/metrics/field_trial.h"
     14 #include "base/metrics/histogram.h"
     15 #include "base/metrics/sparse_histogram.h"
     16 #include "base/path_service.h"
     17 #include "base/rand_util.h"
     18 #include "base/strings/string_number_conversions.h"
     19 #include "base/strings/string_util.h"
     20 #include "base/strings/stringprintf.h"
     21 #include "base/strings/utf_string_conversions.h"
     22 #include "base/time/time.h"
     23 #include "chrome/browser/chrome_notification_types.h"
     24 #include "chrome/browser/download/download_crx_util.h"
     25 #include "chrome/browser/download/download_prefs.h"
     26 #include "chrome/browser/download/download_stats.h"
     27 #include "chrome/browser/extensions/crx_installer.h"
     28 #include "chrome/browser/extensions/install_tracker.h"
     29 #include "chrome/browser/extensions/install_tracker_factory.h"
     30 #include "chrome/browser/extensions/install_verifier.h"
     31 #include "chrome/browser/extensions/shared_module_service.h"
     32 #include "chrome/browser/profiles/profile.h"
     33 #include "chrome/browser/ui/browser_list.h"
     34 #include "chrome/browser/ui/tabs/tab_strip_model.h"
     35 #include "chrome/common/chrome_paths.h"
     36 #include "chrome/common/chrome_switches.h"
     37 #include "components/crx_file/id_util.h"
     38 #include "components/omaha_query_params/omaha_query_params.h"
     39 #include "content/public/browser/browser_thread.h"
     40 #include "content/public/browser/download_manager.h"
     41 #include "content/public/browser/download_save_info.h"
     42 #include "content/public/browser/download_url_parameters.h"
     43 #include "content/public/browser/navigation_controller.h"
     44 #include "content/public/browser/navigation_entry.h"
     45 #include "content/public/browser/notification_details.h"
     46 #include "content/public/browser/notification_service.h"
     47 #include "content/public/browser/notification_source.h"
     48 #include "content/public/browser/render_process_host.h"
     49 #include "content/public/browser/render_view_host.h"
     50 #include "content/public/browser/web_contents.h"
     51 #include "extensions/browser/extension_registry.h"
     52 #include "extensions/browser/extension_system.h"
     53 #include "extensions/common/extension.h"
     54 #include "extensions/common/extension_urls.h"
     55 #include "extensions/common/manifest_constants.h"
     56 #include "extensions/common/manifest_handlers/shared_module_info.h"
     57 #include "net/base/escape.h"
     58 #include "url/gurl.h"
     59 
     60 #if defined(OS_CHROMEOS)
     61 #include "chrome/browser/chromeos/drive/file_system_util.h"
     62 #endif
     63 
     64 using content::BrowserContext;
     65 using content::BrowserThread;
     66 using content::DownloadItem;
     67 using content::DownloadManager;
     68 using content::NavigationController;
     69 using content::DownloadUrlParameters;
     70 
     71 namespace {
     72 
     73 // Key used to attach the Approval to the DownloadItem.
     74 const char kApprovalKey[] = "extensions.webstore_installer";
     75 
     76 const char kInvalidIdError[] = "Invalid id";
     77 const char kDownloadDirectoryError[] = "Could not create download directory";
     78 const char kDownloadCanceledError[] = "Download canceled";
     79 const char kDownloadInterruptedError[] = "Download interrupted";
     80 const char kInvalidDownloadError[] =
     81     "Download was not a valid extension or user script";
     82 const char kDependencyNotFoundError[] = "Dependency not found";
     83 const char kDependencyNotSharedModuleError[] =
     84     "Dependency is not shared module";
     85 const char kInlineInstallSource[] = "inline";
     86 const char kDefaultInstallSource[] = "ondemand";
     87 const char kAppLauncherInstallSource[] = "applauncher";
     88 
     89 // TODO(rockot): Share this duplicated constant with the extension updater.
     90 // See http://crbug.com/371398.
     91 const char kAuthUserQueryKey[] = "authuser";
     92 
     93 const size_t kTimeRemainingMinutesThreshold = 1u;
     94 
     95 // Folder for downloading crx files from the webstore. This is used so that the
     96 // crx files don't go via the usual downloads folder.
     97 const base::FilePath::CharType kWebstoreDownloadFolder[] =
     98     FILE_PATH_LITERAL("Webstore Downloads");
     99 
    100 base::FilePath* g_download_directory_for_tests = NULL;
    101 
    102 // Must be executed on the FILE thread.
    103 void GetDownloadFilePath(
    104     const base::FilePath& download_directory,
    105     const std::string& id,
    106     const base::Callback<void(const base::FilePath&)>& callback) {
    107   // Ensure the download directory exists. TODO(asargent) - make this use
    108   // common code from the downloads system.
    109   if (!base::DirectoryExists(download_directory)) {
    110     if (!base::CreateDirectory(download_directory)) {
    111       BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
    112                               base::Bind(callback, base::FilePath()));
    113       return;
    114     }
    115   }
    116 
    117   // This is to help avoid a race condition between when we generate this
    118   // filename and when the download starts writing to it (think concurrently
    119   // running sharded browser tests installing the same test file, for
    120   // instance).
    121   std::string random_number =
    122       base::Uint64ToString(base::RandGenerator(kuint16max));
    123 
    124   base::FilePath file =
    125       download_directory.AppendASCII(id + "_" + random_number + ".crx");
    126 
    127   int uniquifier =
    128       base::GetUniquePathNumber(file, base::FilePath::StringType());
    129   if (uniquifier > 0) {
    130     file = file.InsertBeforeExtensionASCII(
    131         base::StringPrintf(" (%d)", uniquifier));
    132   }
    133 
    134   BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
    135                           base::Bind(callback, file));
    136 }
    137 
    138 void MaybeAppendAuthUserParameter(const std::string& authuser, GURL* url) {
    139   if (authuser.empty())
    140     return;
    141   std::string old_query = url->query();
    142   url::Component query(0, old_query.length());
    143   url::Component key, value;
    144   // Ensure that the URL doesn't already specify an authuser parameter.
    145   while (url::ExtractQueryKeyValue(
    146              old_query.c_str(), &query, &key, &value)) {
    147     std::string key_string = old_query.substr(key.begin, key.len);
    148     if (key_string == kAuthUserQueryKey) {
    149       return;
    150     }
    151   }
    152   if (!old_query.empty()) {
    153     old_query += "&";
    154   }
    155   std::string authuser_param = base::StringPrintf(
    156       "%s=%s",
    157       kAuthUserQueryKey,
    158       authuser.c_str());
    159 
    160   // TODO(rockot): Share this duplicated code with the extension updater.
    161   // See http://crbug.com/371398.
    162   std::string new_query_string = old_query + authuser_param;
    163   url::Component new_query(0, new_query_string.length());
    164   url::Replacements<char> replacements;
    165   replacements.SetQuery(new_query_string.c_str(), new_query);
    166   *url = url->ReplaceComponents(replacements);
    167 }
    168 
    169 }  // namespace
    170 
    171 namespace extensions {
    172 
    173 // static
    174 GURL WebstoreInstaller::GetWebstoreInstallURL(
    175     const std::string& extension_id,
    176     InstallSource source) {
    177   std::string install_source;
    178   switch (source) {
    179     case INSTALL_SOURCE_INLINE:
    180       install_source = kInlineInstallSource;
    181       break;
    182     case INSTALL_SOURCE_APP_LAUNCHER:
    183       install_source = kAppLauncherInstallSource;
    184       break;
    185     case INSTALL_SOURCE_OTHER:
    186       install_source = kDefaultInstallSource;
    187   }
    188 
    189   CommandLine* cmd_line = CommandLine::ForCurrentProcess();
    190   if (cmd_line->HasSwitch(switches::kAppsGalleryDownloadURL)) {
    191     std::string download_url =
    192         cmd_line->GetSwitchValueASCII(switches::kAppsGalleryDownloadURL);
    193     return GURL(base::StringPrintf(download_url.c_str(),
    194                                    extension_id.c_str()));
    195   }
    196   std::vector<std::string> params;
    197   params.push_back("id=" + extension_id);
    198   if (!install_source.empty())
    199     params.push_back("installsource=" + install_source);
    200   params.push_back("uc");
    201   std::string url_string = extension_urls::GetWebstoreUpdateUrl().spec();
    202 
    203   GURL url(url_string + "?response=redirect&" +
    204            omaha_query_params::OmahaQueryParams::Get(
    205                omaha_query_params::OmahaQueryParams::CRX) +
    206            "&x=" + net::EscapeQueryParamValue(JoinString(params, '&'), true));
    207   DCHECK(url.is_valid());
    208 
    209   return url;
    210 }
    211 
    212 void WebstoreInstaller::Delegate::OnExtensionDownloadStarted(
    213     const std::string& id,
    214     content::DownloadItem* item) {
    215 }
    216 
    217 void WebstoreInstaller::Delegate::OnExtensionDownloadProgress(
    218     const std::string& id,
    219     content::DownloadItem* item) {
    220 }
    221 
    222 WebstoreInstaller::Approval::Approval()
    223     : profile(NULL),
    224       use_app_installed_bubble(false),
    225       skip_post_install_ui(false),
    226       skip_install_dialog(false),
    227       enable_launcher(false),
    228       manifest_check_level(MANIFEST_CHECK_LEVEL_STRICT),
    229       is_ephemeral(false) {
    230 }
    231 
    232 scoped_ptr<WebstoreInstaller::Approval>
    233 WebstoreInstaller::Approval::CreateWithInstallPrompt(Profile* profile) {
    234   scoped_ptr<Approval> result(new Approval());
    235   result->profile = profile;
    236   return result.Pass();
    237 }
    238 
    239 scoped_ptr<WebstoreInstaller::Approval>
    240 WebstoreInstaller::Approval::CreateForSharedModule(Profile* profile) {
    241   scoped_ptr<Approval> result(new Approval());
    242   result->profile = profile;
    243   result->skip_install_dialog = true;
    244   result->skip_post_install_ui = true;
    245   result->manifest_check_level = MANIFEST_CHECK_LEVEL_NONE;
    246   return result.Pass();
    247 }
    248 
    249 scoped_ptr<WebstoreInstaller::Approval>
    250 WebstoreInstaller::Approval::CreateWithNoInstallPrompt(
    251     Profile* profile,
    252     const std::string& extension_id,
    253     scoped_ptr<base::DictionaryValue> parsed_manifest,
    254     bool strict_manifest_check) {
    255   scoped_ptr<Approval> result(new Approval());
    256   result->extension_id = extension_id;
    257   result->profile = profile;
    258   result->manifest = scoped_ptr<Manifest>(
    259       new Manifest(Manifest::INVALID_LOCATION,
    260                    scoped_ptr<base::DictionaryValue>(
    261                        parsed_manifest->DeepCopy())));
    262   result->skip_install_dialog = true;
    263   result->manifest_check_level = strict_manifest_check ?
    264     MANIFEST_CHECK_LEVEL_STRICT : MANIFEST_CHECK_LEVEL_LOOSE;
    265   return result.Pass();
    266 }
    267 
    268 WebstoreInstaller::Approval::~Approval() {}
    269 
    270 const WebstoreInstaller::Approval* WebstoreInstaller::GetAssociatedApproval(
    271     const DownloadItem& download) {
    272   return static_cast<const Approval*>(download.GetUserData(kApprovalKey));
    273 }
    274 
    275 WebstoreInstaller::WebstoreInstaller(Profile* profile,
    276                                      Delegate* delegate,
    277                                      content::WebContents* web_contents,
    278                                      const std::string& id,
    279                                      scoped_ptr<Approval> approval,
    280                                      InstallSource source)
    281     : content::WebContentsObserver(web_contents),
    282       extension_registry_observer_(this),
    283       profile_(profile),
    284       delegate_(delegate),
    285       id_(id),
    286       install_source_(source),
    287       download_item_(NULL),
    288       approval_(approval.release()),
    289       total_modules_(0),
    290       download_started_(false) {
    291   DCHECK_CURRENTLY_ON(BrowserThread::UI);
    292   DCHECK(web_contents);
    293 
    294   registrar_.Add(this,
    295                  extensions::NOTIFICATION_EXTENSION_INSTALL_ERROR,
    296                  content::Source<CrxInstaller>(NULL));
    297   extension_registry_observer_.Add(ExtensionRegistry::Get(profile));
    298 }
    299 
    300 void WebstoreInstaller::Start() {
    301   DCHECK_CURRENTLY_ON(BrowserThread::UI);
    302   AddRef();  // Balanced in ReportSuccess and ReportFailure.
    303 
    304   if (!crx_file::id_util::IdIsValid(id_)) {
    305     ReportFailure(kInvalidIdError, FAILURE_REASON_OTHER);
    306     return;
    307   }
    308 
    309   ExtensionService* extension_service =
    310     ExtensionSystem::Get(profile_)->extension_service();
    311   if (approval_.get() && approval_->dummy_extension.get()) {
    312     extension_service->shared_module_service()->CheckImports(
    313         approval_->dummy_extension.get(), &pending_modules_, &pending_modules_);
    314     // Do not check the return value of CheckImports, the CRX installer
    315     // will report appropriate error messages and fail to install if there
    316     // is an import error.
    317   }
    318 
    319   // Add the extension main module into the list.
    320   SharedModuleInfo::ImportInfo info;
    321   info.extension_id = id_;
    322   pending_modules_.push_back(info);
    323 
    324   total_modules_ = pending_modules_.size();
    325 
    326   std::set<std::string> ids;
    327   std::list<SharedModuleInfo::ImportInfo>::const_iterator i;
    328   for (i = pending_modules_.begin(); i != pending_modules_.end(); ++i) {
    329     ids.insert(i->extension_id);
    330   }
    331   ExtensionSystem::Get(profile_)->install_verifier()->AddProvisional(ids);
    332 
    333   std::string name;
    334   if (!approval_->manifest->value()->GetString(manifest_keys::kName, &name)) {
    335     NOTREACHED();
    336   }
    337   extensions::InstallTracker* tracker =
    338       extensions::InstallTrackerFactory::GetForBrowserContext(profile_);
    339   extensions::InstallObserver::ExtensionInstallParams params(
    340       id_,
    341       name,
    342       approval_->installing_icon,
    343       approval_->manifest->is_app(),
    344       approval_->manifest->is_platform_app());
    345   params.is_ephemeral = approval_->is_ephemeral;
    346   tracker->OnBeginExtensionInstall(params);
    347 
    348   tracker->OnBeginExtensionDownload(id_);
    349 
    350   // TODO(crbug.com/305343): Query manifest of dependencies before
    351   // downloading & installing those dependencies.
    352   DownloadNextPendingModule();
    353 }
    354 
    355 void WebstoreInstaller::Observe(int type,
    356                                 const content::NotificationSource& source,
    357                                 const content::NotificationDetails& details) {
    358   switch (type) {
    359     case extensions::NOTIFICATION_EXTENSION_INSTALL_ERROR: {
    360       CrxInstaller* crx_installer = content::Source<CrxInstaller>(source).ptr();
    361       CHECK(crx_installer);
    362       if (crx_installer != crx_installer_.get())
    363         return;
    364 
    365       // TODO(rdevlin.cronin): Continue removing std::string errors and
    366       // replacing with base::string16. See crbug.com/71980.
    367       const base::string16* error =
    368           content::Details<const base::string16>(details).ptr();
    369       const std::string utf8_error = base::UTF16ToUTF8(*error);
    370       crx_installer_ = NULL;
    371       // ReportFailure releases a reference to this object so it must be the
    372       // last operation in this method.
    373       ReportFailure(utf8_error, FAILURE_REASON_OTHER);
    374       break;
    375     }
    376 
    377     default:
    378       NOTREACHED();
    379   }
    380 }
    381 
    382 void WebstoreInstaller::OnExtensionInstalled(
    383     content::BrowserContext* browser_context,
    384     const Extension* extension,
    385     bool is_update) {
    386   CHECK(profile_->IsSameProfile(Profile::FromBrowserContext(browser_context)));
    387   if (pending_modules_.empty())
    388     return;
    389   SharedModuleInfo::ImportInfo info = pending_modules_.front();
    390   if (extension->id() != info.extension_id)
    391     return;
    392   pending_modules_.pop_front();
    393 
    394   // Clean up local state from the current download.
    395   if (download_item_) {
    396     download_item_->RemoveObserver(this);
    397     download_item_->Remove();
    398     download_item_ = NULL;
    399   }
    400   crx_installer_ = NULL;
    401 
    402   if (pending_modules_.empty()) {
    403     CHECK_EQ(extension->id(), id_);
    404     ReportSuccess();
    405   } else {
    406     const Version version_required(info.minimum_version);
    407     if (version_required.IsValid() &&
    408         extension->version()->CompareTo(version_required) < 0) {
    409       // It should not happen, CrxInstaller will make sure the version is
    410       // equal or newer than version_required.
    411       ReportFailure(kDependencyNotFoundError,
    412                     FAILURE_REASON_DEPENDENCY_NOT_FOUND);
    413     } else if (!SharedModuleInfo::IsSharedModule(extension)) {
    414       // It should not happen, CrxInstaller will make sure it is a shared
    415       // module.
    416       ReportFailure(kDependencyNotSharedModuleError,
    417                     FAILURE_REASON_DEPENDENCY_NOT_SHARED_MODULE);
    418     } else {
    419       DownloadNextPendingModule();
    420     }
    421   }
    422 }
    423 
    424 void WebstoreInstaller::InvalidateDelegate() {
    425   delegate_ = NULL;
    426 }
    427 
    428 void WebstoreInstaller::SetDownloadDirectoryForTests(
    429     base::FilePath* directory) {
    430   g_download_directory_for_tests = directory;
    431 }
    432 
    433 WebstoreInstaller::~WebstoreInstaller() {
    434   if (download_item_) {
    435     download_item_->RemoveObserver(this);
    436     download_item_ = NULL;
    437   }
    438 }
    439 
    440 void WebstoreInstaller::OnDownloadStarted(
    441     DownloadItem* item,
    442     content::DownloadInterruptReason interrupt_reason) {
    443   if (!item) {
    444     DCHECK_NE(content::DOWNLOAD_INTERRUPT_REASON_NONE, interrupt_reason);
    445     ReportFailure(content::DownloadInterruptReasonToString(interrupt_reason),
    446                   FAILURE_REASON_OTHER);
    447     return;
    448   }
    449 
    450   DCHECK_EQ(content::DOWNLOAD_INTERRUPT_REASON_NONE, interrupt_reason);
    451   DCHECK(!pending_modules_.empty());
    452   download_item_ = item;
    453   download_item_->AddObserver(this);
    454   if (pending_modules_.size() > 1) {
    455     // We are downloading a shared module. We need create an approval for it.
    456     scoped_ptr<Approval> approval = Approval::CreateForSharedModule(profile_);
    457     const SharedModuleInfo::ImportInfo& info = pending_modules_.front();
    458     approval->extension_id = info.extension_id;
    459     const Version version_required(info.minimum_version);
    460 
    461     if (version_required.IsValid()) {
    462       approval->minimum_version.reset(
    463           new Version(version_required));
    464     }
    465     download_item_->SetUserData(kApprovalKey, approval.release());
    466   } else {
    467     // It is for the main module of the extension. We should use the provided
    468     // |approval_|.
    469     if (approval_)
    470       download_item_->SetUserData(kApprovalKey, approval_.release());
    471   }
    472 
    473   if (!download_started_) {
    474     if (delegate_)
    475       delegate_->OnExtensionDownloadStarted(id_, download_item_);
    476     download_started_ = true;
    477   }
    478 }
    479 
    480 void WebstoreInstaller::OnDownloadUpdated(DownloadItem* download) {
    481   CHECK_EQ(download_item_, download);
    482 
    483   switch (download->GetState()) {
    484     case DownloadItem::CANCELLED:
    485       ReportFailure(kDownloadCanceledError, FAILURE_REASON_CANCELLED);
    486       break;
    487     case DownloadItem::INTERRUPTED:
    488       RecordInterrupt(download);
    489       ReportFailure(kDownloadInterruptedError, FAILURE_REASON_OTHER);
    490       break;
    491     case DownloadItem::COMPLETE:
    492       // Wait for other notifications if the download is really an extension.
    493       if (!download_crx_util::IsExtensionDownload(*download)) {
    494         ReportFailure(kInvalidDownloadError, FAILURE_REASON_OTHER);
    495       } else {
    496         if (crx_installer_.get())
    497           return;  // DownloadItemImpl calls the observer twice, ignore it.
    498         StartCrxInstaller(*download);
    499 
    500         if (pending_modules_.size() == 1) {
    501           // The download is the last module - the extension main module.
    502           if (delegate_)
    503             delegate_->OnExtensionDownloadProgress(id_, download);
    504           extensions::InstallTracker* tracker =
    505               extensions::InstallTrackerFactory::GetForBrowserContext(profile_);
    506           tracker->OnDownloadProgress(id_, 100);
    507         }
    508       }
    509       // Stop the progress timer if it's running.
    510       download_progress_timer_.Stop();
    511       break;
    512     case DownloadItem::IN_PROGRESS: {
    513       if (delegate_ && pending_modules_.size() == 1) {
    514         // Only report download progress for the main module to |delegrate_|.
    515         delegate_->OnExtensionDownloadProgress(id_, download);
    516       }
    517       UpdateDownloadProgress();
    518       break;
    519     }
    520     default:
    521       // Continue listening if the download is not in one of the above states.
    522       break;
    523   }
    524 }
    525 
    526 void WebstoreInstaller::OnDownloadDestroyed(DownloadItem* download) {
    527   CHECK_EQ(download_item_, download);
    528   download_item_->RemoveObserver(this);
    529   download_item_ = NULL;
    530 }
    531 
    532 void WebstoreInstaller::DownloadNextPendingModule() {
    533   CHECK(!pending_modules_.empty());
    534   if (pending_modules_.size() == 1) {
    535     DCHECK_EQ(id_, pending_modules_.front().extension_id);
    536     DownloadCrx(id_, install_source_);
    537   } else {
    538     DownloadCrx(pending_modules_.front().extension_id, INSTALL_SOURCE_OTHER);
    539   }
    540 }
    541 
    542 void WebstoreInstaller::DownloadCrx(
    543     const std::string& extension_id,
    544     InstallSource source) {
    545   download_url_ = GetWebstoreInstallURL(extension_id, source);
    546   MaybeAppendAuthUserParameter(approval_->authuser, &download_url_);
    547 
    548   base::FilePath user_data_dir;
    549   PathService::Get(chrome::DIR_USER_DATA, &user_data_dir);
    550   base::FilePath download_path = user_data_dir.Append(kWebstoreDownloadFolder);
    551 
    552   base::FilePath download_directory(g_download_directory_for_tests ?
    553       *g_download_directory_for_tests : download_path);
    554 
    555 #if defined(OS_CHROMEOS)
    556   // Do not use drive for extension downloads.
    557   if (drive::util::IsUnderDriveMountPoint(download_directory)) {
    558     download_directory = DownloadPrefs::FromBrowserContext(
    559         profile_)->GetDefaultDownloadDirectoryForProfile();
    560   }
    561 #endif
    562 
    563   BrowserThread::PostTask(
    564       BrowserThread::FILE, FROM_HERE,
    565       base::Bind(&GetDownloadFilePath, download_directory, extension_id,
    566         base::Bind(&WebstoreInstaller::StartDownload, this)));
    567 }
    568 
    569 // http://crbug.com/165634
    570 // http://crbug.com/126013
    571 // The current working theory is that one of the many pointers dereferenced in
    572 // here is occasionally deleted before all of its referers are nullified,
    573 // probably in a callback race. After this comment is released, the crash
    574 // reports should narrow down exactly which pointer it is.  Collapsing all the
    575 // early-returns into a single branch makes it hard to see exactly which pointer
    576 // it is.
    577 void WebstoreInstaller::StartDownload(const base::FilePath& file) {
    578   DCHECK_CURRENTLY_ON(BrowserThread::UI);
    579 
    580   if (file.empty()) {
    581     ReportFailure(kDownloadDirectoryError, FAILURE_REASON_OTHER);
    582     return;
    583   }
    584 
    585   DownloadManager* download_manager =
    586       BrowserContext::GetDownloadManager(profile_);
    587   if (!download_manager) {
    588     ReportFailure(kDownloadDirectoryError, FAILURE_REASON_OTHER);
    589     return;
    590   }
    591 
    592   content::WebContents* contents = web_contents();
    593   if (!contents) {
    594     ReportFailure(kDownloadDirectoryError, FAILURE_REASON_OTHER);
    595     return;
    596   }
    597   if (!contents->GetRenderProcessHost()) {
    598     ReportFailure(kDownloadDirectoryError, FAILURE_REASON_OTHER);
    599     return;
    600   }
    601   if (!contents->GetRenderViewHost()) {
    602     ReportFailure(kDownloadDirectoryError, FAILURE_REASON_OTHER);
    603     return;
    604   }
    605 
    606   content::NavigationController& controller = contents->GetController();
    607   if (!controller.GetBrowserContext()) {
    608     ReportFailure(kDownloadDirectoryError, FAILURE_REASON_OTHER);
    609     return;
    610   }
    611   if (!controller.GetBrowserContext()->GetResourceContext()) {
    612     ReportFailure(kDownloadDirectoryError, FAILURE_REASON_OTHER);
    613     return;
    614   }
    615 
    616   // The download url for the given extension is contained in |download_url_|.
    617   // We will navigate the current tab to this url to start the download. The
    618   // download system will then pass the crx to the CrxInstaller.
    619   RecordDownloadSource(DOWNLOAD_INITIATED_BY_WEBSTORE_INSTALLER);
    620   int render_process_host_id = contents->GetRenderProcessHost()->GetID();
    621   int render_view_host_routing_id =
    622       contents->GetRenderViewHost()->GetRoutingID();
    623   content::ResourceContext* resource_context =
    624       controller.GetBrowserContext()->GetResourceContext();
    625   scoped_ptr<DownloadUrlParameters> params(new DownloadUrlParameters(
    626       download_url_,
    627       render_process_host_id,
    628       render_view_host_routing_id ,
    629       resource_context));
    630   params->set_file_path(file);
    631   if (controller.GetVisibleEntry())
    632     params->set_referrer(
    633         content::Referrer(controller.GetVisibleEntry()->GetURL(),
    634                           blink::WebReferrerPolicyDefault));
    635   params->set_callback(base::Bind(&WebstoreInstaller::OnDownloadStarted, this));
    636   download_manager->DownloadUrl(params.Pass());
    637 }
    638 
    639 void WebstoreInstaller::UpdateDownloadProgress() {
    640   // If the download has gone away, or isn't in progress (in which case we can't
    641   // give a good progress estimate), stop any running timers and return.
    642   if (!download_item_ ||
    643       download_item_->GetState() != DownloadItem::IN_PROGRESS) {
    644     download_progress_timer_.Stop();
    645     return;
    646   }
    647 
    648   int percent = download_item_->PercentComplete();
    649   // Only report progress if percent is more than 0 or we have finished
    650   // downloading at least one of the pending modules.
    651   int finished_modules = total_modules_ - pending_modules_.size();
    652   if (finished_modules > 0 && percent < 0)
    653     percent = 0;
    654   if (percent >= 0) {
    655     percent = (percent + (finished_modules * 100)) / total_modules_;
    656     extensions::InstallTracker* tracker =
    657         extensions::InstallTrackerFactory::GetForBrowserContext(profile_);
    658     tracker->OnDownloadProgress(id_, percent);
    659   }
    660 
    661   // If there's enough time remaining on the download to warrant an update,
    662   // set the timer (overwriting any current timers). Otherwise, stop the
    663   // timer.
    664   base::TimeDelta time_remaining;
    665   if (download_item_->TimeRemaining(&time_remaining) &&
    666       time_remaining >
    667           base::TimeDelta::FromSeconds(kTimeRemainingMinutesThreshold)) {
    668     download_progress_timer_.Start(
    669         FROM_HERE,
    670         base::TimeDelta::FromSeconds(kTimeRemainingMinutesThreshold),
    671         this,
    672         &WebstoreInstaller::UpdateDownloadProgress);
    673   } else {
    674     download_progress_timer_.Stop();
    675   }
    676 }
    677 
    678 void WebstoreInstaller::StartCrxInstaller(const DownloadItem& download) {
    679   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
    680   DCHECK(!crx_installer_.get());
    681 
    682   ExtensionService* service = ExtensionSystem::Get(profile_)->
    683       extension_service();
    684   CHECK(service);
    685 
    686   const Approval* approval = GetAssociatedApproval(download);
    687   DCHECK(approval);
    688 
    689   crx_installer_ = download_crx_util::CreateCrxInstaller(profile_, download);
    690 
    691   crx_installer_->set_expected_id(approval->extension_id);
    692   crx_installer_->set_is_gallery_install(true);
    693   crx_installer_->set_allow_silent_install(true);
    694 
    695   crx_installer_->InstallCrx(download.GetFullPath());
    696 }
    697 
    698 void WebstoreInstaller::ReportFailure(const std::string& error,
    699                                       FailureReason reason) {
    700   if (delegate_) {
    701     delegate_->OnExtensionInstallFailure(id_, error, reason);
    702     delegate_ = NULL;
    703   }
    704 
    705   extensions::InstallTracker* tracker =
    706       extensions::InstallTrackerFactory::GetForBrowserContext(profile_);
    707   tracker->OnInstallFailure(id_);
    708 
    709   Release();  // Balanced in Start().
    710 }
    711 
    712 void WebstoreInstaller::ReportSuccess() {
    713   if (delegate_) {
    714     delegate_->OnExtensionInstallSuccess(id_);
    715     delegate_ = NULL;
    716   }
    717 
    718   Release();  // Balanced in Start().
    719 }
    720 
    721 void WebstoreInstaller::RecordInterrupt(const DownloadItem* download) const {
    722   UMA_HISTOGRAM_SPARSE_SLOWLY("Extensions.WebstoreDownload.InterruptReason",
    723                               download->GetLastReason());
    724 
    725   // Use logarithmic bin sizes up to 1 TB.
    726   const int kNumBuckets = 30;
    727   const int64 kMaxSizeKb = 1 << kNumBuckets;
    728   UMA_HISTOGRAM_CUSTOM_COUNTS(
    729       "Extensions.WebstoreDownload.InterruptReceivedKBytes",
    730       download->GetReceivedBytes() / 1024,
    731       1,
    732       kMaxSizeKb,
    733       kNumBuckets);
    734   int64 total_bytes = download->GetTotalBytes();
    735   if (total_bytes >= 0) {
    736     UMA_HISTOGRAM_CUSTOM_COUNTS(
    737         "Extensions.WebstoreDownload.InterruptTotalKBytes",
    738         total_bytes / 1024,
    739         1,
    740         kMaxSizeKb,
    741         kNumBuckets);
    742   }
    743   UMA_HISTOGRAM_BOOLEAN(
    744       "Extensions.WebstoreDownload.InterruptTotalSizeUnknown",
    745       total_bytes <= 0);
    746 }
    747 
    748 }  // namespace extensions
    749