src/chrome/browser/extensions/user_script_master.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/browser/extensions/user_script_master.h"
   6
   7 #include <map>
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/bind.h"
  12 #include "base/file_util.h"
  13 #include "base/files/file_path.h"
  14 #include "base/pickle.h"
  15 #include "base/stl_util.h"
  16 #include "base/strings/string_util.h"
  17 #include "base/threading/thread.h"
  18 #include "base/version.h"
  19 #include "chrome/browser/chrome_notification_types.h"
  20 #include "chrome/browser/extensions/extension_service.h"
  21 #include "chrome/browser/extensions/extension_util.h"
  22 #include "chrome/browser/extensions/image_loader.h"
  23 #include "chrome/browser/profiles/profile.h"
  24 #include "chrome/common/extensions/api/i18n/default_locale_handler.h"
  25 #include "chrome/common/extensions/extension_file_util.h"
  26 #include "chrome/common/extensions/manifest_handlers/content_scripts_handler.h"
  27 #include "chrome/common/extensions/message_bundle.h"
  28 #include "content/public/browser/notification_service.h"
  29 #include "content/public/browser/render_process_host.h"
  30 #include "extensions/browser/extension_system.h"
  31 #include "extensions/common/extension.h"
  32 #include "extensions/common/extension_resource.h"
  33 #include "extensions/common/extension_set.h"
  34 #include "ui/base/resource/resource_bundle.h"
  35
  36 using content::BrowserThread;
  37
  38 namespace extensions {
  39
  40 // Helper function to parse greasesmonkey headers
  41 static bool GetDeclarationValue(const base::StringPiece& line,
  42                                 const base::StringPiece& prefix,
  43                                 std::string* value) {
  44   base::StringPiece::size_type index = line.find(prefix);
  45   if (index == base::StringPiece::npos)
  46     return false;
  47
  48   std::string temp(line.data() + index + prefix.length(),
  49                    line.length() - index - prefix.length());
  50
  51   if (temp.empty() || !IsWhitespace(temp[0]))
  52     return false;
  53
  54   base::TrimWhitespaceASCII(temp, base::TRIM_ALL, value);
  55   return true;
  56 }
  57
  58 UserScriptMaster::ScriptReloader::ScriptReloader(UserScriptMaster* master)
  59     : master_(master) {
  60   CHECK(BrowserThread::GetCurrentThreadIdentifier(&master_thread_id_));
  61 }
  62
  63 // static
  64 bool UserScriptMaster::ScriptReloader::ParseMetadataHeader(
  65       const base::StringPiece& script_text, UserScript* script) {
  66   // http://wiki.greasespot.net/Metadata_block
  67   base::StringPiece line;
  68   size_t line_start = 0;
  69   size_t line_end = line_start;
  70   bool in_metadata = false;
  71
  72   static const base::StringPiece kUserScriptBegin("// ==UserScript==");
  73   static const base::StringPiece kUserScriptEng("// ==/UserScript==");
  74   static const base::StringPiece kNamespaceDeclaration("// @namespace");
  75   static const base::StringPiece kNameDeclaration("// @name");
  76   static const base::StringPiece kVersionDeclaration("// @version");
  77   static const base::StringPiece kDescriptionDeclaration("// @description");
  78   static const base::StringPiece kIncludeDeclaration("// @include");
  79   static const base::StringPiece kExcludeDeclaration("// @exclude");
  80   static const base::StringPiece kMatchDeclaration("// @match");
  81   static const base::StringPiece kExcludeMatchDeclaration("// @exclude_match");
  82   static const base::StringPiece kRunAtDeclaration("// @run-at");
  83   static const base::StringPiece kRunAtDocumentStartValue("document-start");
  84   static const base::StringPiece kRunAtDocumentEndValue("document-end");
  85   static const base::StringPiece kRunAtDocumentIdleValue("document-idle");
  86
  87   while (line_start < script_text.length()) {
  88     line_end = script_text.find('\n', line_start);
  89
  90     // Handle the case where there is no trailing newline in the file.
  91     if (line_end == std::string::npos)
  92       line_end = script_text.length() - 1;
  93
  94     line.set(script_text.data() + line_start, line_end - line_start);
  95
  96     if (!in_metadata) {
  97       if (line.starts_with(kUserScriptBegin))
  98         in_metadata = true;
  99     } else {
 100       if (line.starts_with(kUserScriptEng))
 101         break;
 102
 103       std::string value;
 104       if (GetDeclarationValue(line, kIncludeDeclaration, &value)) {
 105         // We escape some characters that MatchPattern() considers special.
 106         ReplaceSubstringsAfterOffset(&value, 0, "\\", "\\\\");
 107         ReplaceSubstringsAfterOffset(&value, 0, "?", "\\?");
 108         script->add_glob(value);
 109       } else if (GetDeclarationValue(line, kExcludeDeclaration, &value)) {
 110         ReplaceSubstringsAfterOffset(&value, 0, "\\", "\\\\");
 111         ReplaceSubstringsAfterOffset(&value, 0, "?", "\\?");
 112         script->add_exclude_glob(value);
 113       } else if (GetDeclarationValue(line, kNamespaceDeclaration, &value)) {
 114         script->set_name_space(value);
 115       } else if (GetDeclarationValue(line, kNameDeclaration, &value)) {
 116         script->set_name(value);
 117       } else if (GetDeclarationValue(line, kVersionDeclaration, &value)) {
 118         Version version(value);
 119         if (version.IsValid())
 120           script->set_version(version.GetString());
 121       } else if (GetDeclarationValue(line, kDescriptionDeclaration, &value)) {
 122         script->set_description(value);
 123       } else if (GetDeclarationValue(line, kMatchDeclaration, &value)) {
 124         URLPattern pattern(UserScript::ValidUserScriptSchemes());
 125         if (URLPattern::PARSE_SUCCESS != pattern.Parse(value))
 126           return false;
 127         script->add_url_pattern(pattern);
 128       } else if (GetDeclarationValue(line, kExcludeMatchDeclaration, &value)) {
 129         URLPattern exclude(UserScript::ValidUserScriptSchemes());
 130         if (URLPattern::PARSE_SUCCESS != exclude.Parse(value))
 131           return false;
 132         script->add_exclude_url_pattern(exclude);
 133       } else if (GetDeclarationValue(line, kRunAtDeclaration, &value)) {
 134         if (value == kRunAtDocumentStartValue)
 135           script->set_run_location(UserScript::DOCUMENT_START);
 136         else if (value == kRunAtDocumentEndValue)
 137           script->set_run_location(UserScript::DOCUMENT_END);
 138         else if (value == kRunAtDocumentIdleValue)
 139           script->set_run_location(UserScript::DOCUMENT_IDLE);
 140         else
 141           return false;
 142       }
 143
 144       // TODO(aa): Handle more types of metadata.
 145     }
 146
 147     line_start = line_end + 1;
 148   }
 149
 150   // If no patterns were specified, default to @include *. This is what
 151   // Greasemonkey does.
 152   if (script->globs().empty() && script->url_patterns().is_empty())
 153     script->add_glob("*");
 154
 155   return true;
 156 }
 157
 158 void UserScriptMaster::ScriptReloader::StartLoad(
 159     const UserScriptList& user_scripts,
 160     const ExtensionsInfo& extensions_info_) {
 161   // Add a reference to ourselves to keep ourselves alive while we're running.
 162   // Balanced by NotifyMaster().
 163   AddRef();
 164
 165   this->extensions_info_ = extensions_info_;
 166   BrowserThread::PostTask(
 167       BrowserThread::FILE, FROM_HERE,
 168       base::Bind(
 169           &UserScriptMaster::ScriptReloader::RunLoad, this, user_scripts));
 170 }
 171
 172 UserScriptMaster::ScriptReloader::~ScriptReloader() {}
 173
 174 void UserScriptMaster::ScriptReloader::NotifyMaster(
 175     base::SharedMemory* memory) {
 176   // The master went away, so these new scripts aren't useful anymore.
 177   if (!master_)
 178     delete memory;
 179   else
 180     master_->NewScriptsAvailable(memory);
 181
 182   // Drop our self-reference.
 183   // Balances StartLoad().
 184   Release();
 185 }
 186
 187 static bool LoadScriptContent(UserScript::File* script_file,
 188                               const SubstitutionMap* localization_messages) {
 189   std::string content;
 190   const base::FilePath& path = ExtensionResource::GetFilePath(
 191       script_file->extension_root(), script_file->relative_path(),
 192       ExtensionResource::SYMLINKS_MUST_RESOLVE_WITHIN_ROOT);
 193   if (path.empty()) {
 194     int resource_id;
 195     if (extensions::ImageLoader::IsComponentExtensionResource(
 196             script_file->extension_root(), script_file->relative_path(),
 197             &resource_id)) {
 198       const ResourceBundle& rb = ResourceBundle::GetSharedInstance();
 199       content = rb.GetRawDataResource(resource_id).as_string();
 200     } else {
 201       LOG(WARNING) << "Failed to get file path to "
 202                    << script_file->relative_path().value() << " from "
 203                    << script_file->extension_root().value();
 204       return false;
 205     }
 206   } else {
 207     if (!base::ReadFileToString(path, &content)) {
 208       LOG(WARNING) << "Failed to load user script file: " << path.value();
 209       return false;
 210     }
 211   }
 212
 213   // Localize the content.
 214   if (localization_messages) {
 215     std::string error;
 216     MessageBundle::ReplaceMessagesWithExternalDictionary(
 217         *localization_messages, &content, &error);
 218     if (!error.empty()) {
 219       LOG(WARNING) << "Failed to replace messages in script: " << error;
 220     }
 221   }
 222
 223   // Remove BOM from the content.
 224   std::string::size_type index = content.find(base::kUtf8ByteOrderMark);
 225   if (index == 0) {
 226     script_file->set_content(content.substr(strlen(base::kUtf8ByteOrderMark)));
 227   } else {
 228     script_file->set_content(content);
 229   }
 230
 231   return true;
 232 }
 233
 234 void UserScriptMaster::ScriptReloader::LoadUserScripts(
 235     UserScriptList* user_scripts) {
 236   for (size_t i = 0; i < user_scripts->size(); ++i) {
 237     UserScript& script = user_scripts->at(i);
 238     scoped_ptr<SubstitutionMap> localization_messages(
 239         GetLocalizationMessages(script.extension_id()));
 240     for (size_t k = 0; k < script.js_scripts().size(); ++k) {
 241       UserScript::File& script_file = script.js_scripts()[k];
 242       if (script_file.GetContent().empty())
 243         LoadScriptContent(&script_file, NULL);
 244     }
 245     for (size_t k = 0; k < script.css_scripts().size(); ++k) {
 246       UserScript::File& script_file = script.css_scripts()[k];
 247       if (script_file.GetContent().empty())
 248         LoadScriptContent(&script_file, localization_messages.get());
 249     }
 250   }
 251 }
 252
 253 SubstitutionMap* UserScriptMaster::ScriptReloader::GetLocalizationMessages(
 254     std::string extension_id) {
 255   if (extensions_info_.find(extension_id) == extensions_info_.end()) {
 256     return NULL;
 257   }
 258
 259   return extension_file_util::LoadMessageBundleSubstitutionMap(
 260       extensions_info_[extension_id].first,
 261       extension_id,
 262       extensions_info_[extension_id].second);
 263 }
 264
 265 // Pickle user scripts and return pointer to the shared memory.
 266 static base::SharedMemory* Serialize(const UserScriptList& scripts) {
 267   Pickle pickle;
 268   pickle.WriteUInt64(scripts.size());
 269   for (size_t i = 0; i < scripts.size(); i++) {
 270     const UserScript& script = scripts[i];
 271     // TODO(aa): This can be replaced by sending content script metadata to
 272     // renderers along with other extension data in ExtensionMsg_Loaded.
 273     // See crbug.com/70516.
 274     script.Pickle(&pickle);
 275     // Write scripts as 'data' so that we can read it out in the slave without
 276     // allocating a new string.
 277     for (size_t j = 0; j < script.js_scripts().size(); j++) {
 278       base::StringPiece contents = script.js_scripts()[j].GetContent();
 279       pickle.WriteData(contents.data(), contents.length());
 280     }
 281     for (size_t j = 0; j < script.css_scripts().size(); j++) {
 282       base::StringPiece contents = script.css_scripts()[j].GetContent();
 283       pickle.WriteData(contents.data(), contents.length());
 284     }
 285   }
 286
 287   // Create the shared memory object.
 288   base::SharedMemory shared_memory;
 289
 290   base::SharedMemoryCreateOptions options;
 291   options.size = pickle.size();
 292   options.share_read_only = true;
 293   if (!shared_memory.Create(options))
 294     return NULL;
 295
 296   if (!shared_memory.Map(pickle.size()))
 297     return NULL;
 298
 299   // Copy the pickle to shared memory.
 300   memcpy(shared_memory.memory(), pickle.data(), pickle.size());
 301
 302   base::SharedMemoryHandle readonly_handle;
 303   if (!shared_memory.ShareReadOnlyToProcess(base::GetCurrentProcessHandle(),
 304                                             &readonly_handle))
 305     return NULL;
 306
 307   return new base::SharedMemory(readonly_handle, /*read_only=*/true);
 308 }
 309
 310 // This method will be called on the file thread.
 311 void UserScriptMaster::ScriptReloader::RunLoad(
 312     const UserScriptList& user_scripts) {
 313   LoadUserScripts(const_cast<UserScriptList*>(&user_scripts));
 314
 315   // Scripts now contains list of up-to-date scripts. Load the content in the
 316   // shared memory and let the master know it's ready. We need to post the task
 317   // back even if no scripts ware found to balance the AddRef/Release calls.
 318   BrowserThread::PostTask(
 319       master_thread_id_, FROM_HERE,
 320       base::Bind(
 321           &ScriptReloader::NotifyMaster, this, Serialize(user_scripts)));
 322 }
 323
 324
 325 UserScriptMaster::UserScriptMaster(Profile* profile)
 326     : extensions_service_ready_(false),
 327       pending_load_(false),
 328       profile_(profile) {
 329   registrar_.Add(this, chrome::NOTIFICATION_EXTENSIONS_READY,
 330                  content::Source<Profile>(profile_));
 331   registrar_.Add(this, chrome::NOTIFICATION_EXTENSION_LOADED,
 332                  content::Source<Profile>(profile_));
 333   registrar_.Add(this, chrome::NOTIFICATION_EXTENSION_UNLOADED_DEPRECATED,
 334                  content::Source<Profile>(profile_));
 335   registrar_.Add(this, content::NOTIFICATION_RENDERER_PROCESS_CREATED,
 336                  content::NotificationService::AllBrowserContextsAndSources());
 337 }
 338
 339 UserScriptMaster::~UserScriptMaster() {
 340   if (script_reloader_.get())
 341     script_reloader_->DisownMaster();
 342 }
 343
 344 void UserScriptMaster::NewScriptsAvailable(base::SharedMemory* handle) {
 345   // Ensure handle is deleted or released.
 346   scoped_ptr<base::SharedMemory> handle_deleter(handle);
 347
 348   if (pending_load_) {
 349     // While we were loading, there were further changes.  Don't bother
 350     // notifying about these scripts and instead just immediately reload.
 351     pending_load_ = false;
 352     StartLoad();
 353   } else {
 354     // We're no longer loading.
 355     script_reloader_ = NULL;
 356     // We've got scripts ready to go.
 357     shared_memory_.swap(handle_deleter);
 358
 359     for (content::RenderProcessHost::iterator i(
 360             content::RenderProcessHost::AllHostsIterator());
 361          !i.IsAtEnd(); i.Advance()) {
 362       SendUpdate(i.GetCurrentValue(), handle);
 363     }
 364
 365     content::NotificationService::current()->Notify(
 366         chrome::NOTIFICATION_USER_SCRIPTS_UPDATED,
 367         content::Source<Profile>(profile_),
 368         content::Details<base::SharedMemory>(handle));
 369   }
 370 }
 371
 372 void UserScriptMaster::Observe(int type,
 373                                const content::NotificationSource& source,
 374                                const content::NotificationDetails& details) {
 375   bool should_start_load = false;
 376   switch (type) {
 377     case chrome::NOTIFICATION_EXTENSIONS_READY:
 378       extensions_service_ready_ = true;
 379       should_start_load = true;
 380       break;
 381     case chrome::NOTIFICATION_EXTENSION_LOADED: {
 382       // Add any content scripts inside the extension.
 383       const Extension* extension =
 384           content::Details<const Extension>(details).ptr();
 385       extensions_info_[extension->id()] =
 386           ExtensionSet::ExtensionPathAndDefaultLocale(
 387               extension->path(), LocaleInfo::GetDefaultLocale(extension));
 388       bool incognito_enabled =
 389           util::IsIncognitoEnabled(extension->id(), profile_);
 390       const UserScriptList& scripts =
 391           ContentScriptsInfo::GetContentScripts(extension);
 392       for (UserScriptList::const_iterator iter = scripts.begin();
 393            iter != scripts.end(); ++iter) {
 394         user_scripts_.push_back(*iter);
 395         user_scripts_.back().set_incognito_enabled(incognito_enabled);
 396       }
 397       if (extensions_service_ready_)
 398         should_start_load = true;
 399       break;
 400     }
 401     case chrome::NOTIFICATION_EXTENSION_UNLOADED_DEPRECATED: {
 402       // Remove any content scripts.
 403       const Extension* extension =
 404           content::Details<UnloadedExtensionInfo>(details)->extension;
 405       extensions_info_.erase(extension->id());
 406       UserScriptList new_user_scripts;
 407       for (UserScriptList::iterator iter = user_scripts_.begin();
 408            iter != user_scripts_.end(); ++iter) {
 409         if (iter->extension_id() != extension->id())
 410           new_user_scripts.push_back(*iter);
 411       }
 412       user_scripts_ = new_user_scripts;
 413       should_start_load = true;
 414       break;
 415     }
 416     case content::NOTIFICATION_RENDERER_PROCESS_CREATED: {
 417       content::RenderProcessHost* process =
 418           content::Source<content::RenderProcessHost>(source).ptr();
 419       Profile* profile = Profile::FromBrowserContext(
 420           process->GetBrowserContext());
 421       if (!profile_->IsSameProfile(profile))
 422         return;
 423       if (ScriptsReady())
 424         SendUpdate(process, GetSharedMemory());
 425       break;
 426     }
 427     default:
 428       DCHECK(false);
 429   }
 430
 431   if (should_start_load) {
 432     if (script_reloader_.get()) {
 433       pending_load_ = true;
 434     } else {
 435       StartLoad();
 436     }
 437   }
 438 }
 439
 440 void UserScriptMaster::StartLoad() {
 441   if (!script_reloader_.get())
 442     script_reloader_ = new ScriptReloader(this);
 443
 444   script_reloader_->StartLoad(user_scripts_, extensions_info_);
 445 }
 446
 447 void UserScriptMaster::SendUpdate(content::RenderProcessHost* process,
 448                                   base::SharedMemory* shared_memory) {
 449   // Don't allow injection of content scripts into <webview>.
 450   if (process->IsGuest())
 451     return;
 452
 453   Profile* profile = Profile::FromBrowserContext(process->GetBrowserContext());
 454   // Make sure we only send user scripts to processes in our profile.
 455   if (!profile_->IsSameProfile(profile))
 456     return;
 457
 458   // If the process is being started asynchronously, early return.  We'll end up
 459   // calling InitUserScripts when it's created which will call this again.
 460   base::ProcessHandle handle = process->GetHandle();
 461   if (!handle)
 462     return;
 463
 464   base::SharedMemoryHandle handle_for_process;
 465   if (!shared_memory->ShareToProcess(handle, &handle_for_process))
 466     return;  // This can legitimately fail if the renderer asserts at startup.
 467
 468   if (base::SharedMemory::IsHandleValid(handle_for_process))
 469     process->Send(new ExtensionMsg_UpdateUserScripts(handle_for_process));
 470 }
 471
 472 }  // namespace extensions