1 // Copyright (c) 2011 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 <string> 8 #include <vector> 9 10 #include "base/file_path.h" 11 #include "base/file_util.h" 12 #include "base/path_service.h" 13 #include "base/pickle.h" 14 #include "base/stl_util-inl.h" 15 #include "base/string_util.h" 16 #include "base/threading/thread.h" 17 #include "base/version.h" 18 #include "chrome/browser/extensions/extension_service.h" 19 #include "chrome/browser/profiles/profile.h" 20 #include "chrome/common/extensions/extension.h" 21 #include "chrome/common/extensions/extension_resource.h" 22 #include "chrome/common/url_constants.h" 23 #include "content/common/notification_service.h" 24 #include "net/base/net_util.h" 25 26 27 // Helper function to parse greasesmonkey headers 28 static bool GetDeclarationValue(const base::StringPiece& line, 29 const base::StringPiece& prefix, 30 std::string* value) { 31 base::StringPiece::size_type index = line.find(prefix); 32 if (index == base::StringPiece::npos) 33 return false; 34 35 std::string temp(line.data() + index + prefix.length(), 36 line.length() - index - prefix.length()); 37 38 if (temp.empty() || !IsWhitespace(temp[0])) 39 return false; 40 41 TrimWhitespaceASCII(temp, TRIM_ALL, value); 42 return true; 43 } 44 45 UserScriptMaster::ScriptReloader::ScriptReloader(UserScriptMaster* master) 46 : master_(master) { 47 CHECK(BrowserThread::GetCurrentThreadIdentifier(&master_thread_id_)); 48 } 49 50 // static 51 bool UserScriptMaster::ScriptReloader::ParseMetadataHeader( 52 const base::StringPiece& script_text, UserScript* script) { 53 // http://wiki.greasespot.net/Metadata_block 54 base::StringPiece line; 55 size_t line_start = 0; 56 size_t line_end = line_start; 57 bool in_metadata = false; 58 59 static const base::StringPiece kUserScriptBegin("// ==UserScript=="); 60 static const base::StringPiece kUserScriptEng("// ==/UserScript=="); 61 static const base::StringPiece kNamespaceDeclaration("// @namespace"); 62 static const base::StringPiece kNameDeclaration("// @name"); 63 static const base::StringPiece kVersionDeclaration("// @version"); 64 static const base::StringPiece kDescriptionDeclaration("// @description"); 65 static const base::StringPiece kIncludeDeclaration("// @include"); 66 static const base::StringPiece kExcludeDeclaration("// @exclude"); 67 static const base::StringPiece kMatchDeclaration("// @match"); 68 static const base::StringPiece kRunAtDeclaration("// @run-at"); 69 static const base::StringPiece kRunAtDocumentStartValue("document-start"); 70 static const base::StringPiece kRunAtDocumentEndValue("document-end"); 71 72 while (line_start < script_text.length()) { 73 line_end = script_text.find('\n', line_start); 74 75 // Handle the case where there is no trailing newline in the file. 76 if (line_end == std::string::npos) 77 line_end = script_text.length() - 1; 78 79 line.set(script_text.data() + line_start, line_end - line_start); 80 81 if (!in_metadata) { 82 if (line.starts_with(kUserScriptBegin)) 83 in_metadata = true; 84 } else { 85 if (line.starts_with(kUserScriptEng)) 86 break; 87 88 std::string value; 89 if (GetDeclarationValue(line, kIncludeDeclaration, &value)) { 90 // We escape some characters that MatchPattern() considers special. 91 ReplaceSubstringsAfterOffset(&value, 0, "\\", "\\\\"); 92 ReplaceSubstringsAfterOffset(&value, 0, "?", "\\?"); 93 script->add_glob(value); 94 } else if (GetDeclarationValue(line, kExcludeDeclaration, &value)) { 95 ReplaceSubstringsAfterOffset(&value, 0, "\\", "\\\\"); 96 ReplaceSubstringsAfterOffset(&value, 0, "?", "\\?"); 97 script->add_exclude_glob(value); 98 } else if (GetDeclarationValue(line, kNamespaceDeclaration, &value)) { 99 script->set_name_space(value); 100 } else if (GetDeclarationValue(line, kNameDeclaration, &value)) { 101 script->set_name(value); 102 } else if (GetDeclarationValue(line, kVersionDeclaration, &value)) { 103 scoped_ptr<Version> version(Version::GetVersionFromString(value)); 104 if (version.get()) 105 script->set_version(version->GetString()); 106 } else if (GetDeclarationValue(line, kDescriptionDeclaration, &value)) { 107 script->set_description(value); 108 } else if (GetDeclarationValue(line, kMatchDeclaration, &value)) { 109 URLPattern pattern(UserScript::kValidUserScriptSchemes); 110 if (URLPattern::PARSE_SUCCESS != 111 pattern.Parse(value, URLPattern::PARSE_LENIENT)) 112 return false; 113 script->add_url_pattern(pattern); 114 } else if (GetDeclarationValue(line, kRunAtDeclaration, &value)) { 115 if (value == kRunAtDocumentStartValue) 116 script->set_run_location(UserScript::DOCUMENT_START); 117 else if (value != kRunAtDocumentEndValue) 118 return false; 119 } 120 121 // TODO(aa): Handle more types of metadata. 122 } 123 124 line_start = line_end + 1; 125 } 126 127 // If no patterns were specified, default to @include *. This is what 128 // Greasemonkey does. 129 if (script->globs().empty() && script->url_patterns().empty()) 130 script->add_glob("*"); 131 132 return true; 133 } 134 135 void UserScriptMaster::ScriptReloader::StartScan( 136 const FilePath& script_dir, const UserScriptList& lone_scripts) { 137 // Add a reference to ourselves to keep ourselves alive while we're running. 138 // Balanced by NotifyMaster(). 139 AddRef(); 140 BrowserThread::PostTask( 141 BrowserThread::FILE, FROM_HERE, 142 NewRunnableMethod( 143 this, &UserScriptMaster::ScriptReloader::RunScan, script_dir, 144 lone_scripts)); 145 } 146 147 void UserScriptMaster::ScriptReloader::NotifyMaster( 148 base::SharedMemory* memory) { 149 // The master went away, so these new scripts aren't useful anymore. 150 if (!master_) 151 delete memory; 152 else 153 master_->NewScriptsAvailable(memory); 154 155 // Drop our self-reference. 156 // Balances StartScan(). 157 Release(); 158 } 159 160 static bool LoadScriptContent(UserScript::File* script_file) { 161 std::string content; 162 const FilePath& path = ExtensionResource::GetFilePath( 163 script_file->extension_root(), script_file->relative_path()); 164 if (path.empty() || !file_util::ReadFileToString(path, &content)) { 165 LOG(WARNING) << "Failed to load user script file: " << path.value(); 166 return false; 167 } 168 169 // Remove BOM from the content. 170 std::string::size_type index = content.find(kUtf8ByteOrderMark); 171 if (index == 0) { 172 script_file->set_content(content.substr(strlen(kUtf8ByteOrderMark))); 173 } else { 174 script_file->set_content(content); 175 } 176 177 return true; 178 } 179 180 // static 181 void UserScriptMaster::ScriptReloader::LoadScriptsFromDirectory( 182 const FilePath& script_dir, UserScriptList* result) { 183 // Clear the list. We will populate it with the scripts found in script_dir. 184 result->clear(); 185 186 // Find all the scripts in |script_dir|. 187 if (!script_dir.value().empty()) { 188 // Create the "<Profile>/User Scripts" directory if it doesn't exist 189 if (!file_util::DirectoryExists(script_dir)) 190 file_util::CreateDirectory(script_dir); 191 192 file_util::FileEnumerator enumerator(script_dir, false, 193 file_util::FileEnumerator::FILES, 194 FILE_PATH_LITERAL("*.user.js")); 195 for (FilePath file = enumerator.Next(); !file.value().empty(); 196 file = enumerator.Next()) { 197 result->push_back(UserScript()); 198 UserScript& user_script = result->back(); 199 200 // We default standalone user scripts to document-end for better 201 // Greasemonkey compatibility. 202 user_script.set_run_location(UserScript::DOCUMENT_END); 203 204 // Push single js file in this UserScript. 205 GURL url(std::string(chrome::kUserScriptScheme) + ":/" + 206 net::FilePathToFileURL(file).ExtractFileName()); 207 user_script.js_scripts().push_back(UserScript::File( 208 script_dir, file.BaseName(), url)); 209 UserScript::File& script_file = user_script.js_scripts().back(); 210 if (!LoadScriptContent(&script_file)) 211 result->pop_back(); 212 else 213 ParseMetadataHeader(script_file.GetContent(), &user_script); 214 } 215 } 216 } 217 218 static void LoadLoneScripts(UserScriptList* lone_scripts) { 219 for (size_t i = 0; i < lone_scripts->size(); ++i) { 220 UserScript& script = lone_scripts->at(i); 221 for (size_t k = 0; k < script.js_scripts().size(); ++k) { 222 UserScript::File& script_file = script.js_scripts()[k]; 223 if (script_file.GetContent().empty()) 224 LoadScriptContent(&script_file); 225 } 226 for (size_t k = 0; k < script.css_scripts().size(); ++k) { 227 UserScript::File& script_file = script.css_scripts()[k]; 228 if (script_file.GetContent().empty()) 229 LoadScriptContent(&script_file); 230 } 231 } 232 } 233 234 // Pickle user scripts and return pointer to the shared memory. 235 static base::SharedMemory* Serialize(const UserScriptList& scripts) { 236 Pickle pickle; 237 pickle.WriteSize(scripts.size()); 238 for (size_t i = 0; i < scripts.size(); i++) { 239 const UserScript& script = scripts[i]; 240 // TODO(aa): This can be replaced by sending content script metadata to 241 // renderers along with other extension data in ExtensionMsg_Loaded. 242 // See crbug.com/70516. 243 script.Pickle(&pickle); 244 // Write scripts as 'data' so that we can read it out in the slave without 245 // allocating a new string. 246 for (size_t j = 0; j < script.js_scripts().size(); j++) { 247 base::StringPiece contents = script.js_scripts()[j].GetContent(); 248 pickle.WriteData(contents.data(), contents.length()); 249 } 250 for (size_t j = 0; j < script.css_scripts().size(); j++) { 251 base::StringPiece contents = script.css_scripts()[j].GetContent(); 252 pickle.WriteData(contents.data(), contents.length()); 253 } 254 } 255 256 // Create the shared memory object. 257 scoped_ptr<base::SharedMemory> shared_memory(new base::SharedMemory()); 258 259 if (!shared_memory->CreateAndMapAnonymous(pickle.size())) 260 return NULL; 261 262 // Copy the pickle to shared memory. 263 memcpy(shared_memory->memory(), pickle.data(), pickle.size()); 264 265 return shared_memory.release(); 266 } 267 268 // This method will be called from the file thread 269 void UserScriptMaster::ScriptReloader::RunScan( 270 const FilePath script_dir, UserScriptList lone_script) { 271 UserScriptList scripts; 272 // Get list of user scripts. 273 if (!script_dir.empty()) 274 LoadScriptsFromDirectory(script_dir, &scripts); 275 276 LoadLoneScripts(&lone_script); 277 278 // Merge with the explicit scripts 279 scripts.reserve(scripts.size() + lone_script.size()); 280 scripts.insert(scripts.end(), 281 lone_script.begin(), lone_script.end()); 282 283 // Scripts now contains list of up-to-date scripts. Load the content in the 284 // shared memory and let the master know it's ready. We need to post the task 285 // back even if no scripts ware found to balance the AddRef/Release calls 286 BrowserThread::PostTask( 287 master_thread_id_, FROM_HERE, 288 NewRunnableMethod( 289 this, &ScriptReloader::NotifyMaster, Serialize(scripts))); 290 } 291 292 293 UserScriptMaster::UserScriptMaster(const FilePath& script_dir, Profile* profile) 294 : user_script_dir_(script_dir), 295 extensions_service_ready_(false), 296 pending_scan_(false), 297 profile_(profile) { 298 registrar_.Add(this, NotificationType::EXTENSIONS_READY, 299 Source<Profile>(profile_)); 300 registrar_.Add(this, NotificationType::EXTENSION_LOADED, 301 Source<Profile>(profile_)); 302 registrar_.Add(this, NotificationType::EXTENSION_UNLOADED, 303 Source<Profile>(profile_)); 304 registrar_.Add(this, NotificationType::EXTENSION_USER_SCRIPTS_UPDATED, 305 Source<Profile>(profile_)); 306 } 307 308 UserScriptMaster::~UserScriptMaster() { 309 if (script_reloader_) 310 script_reloader_->DisownMaster(); 311 } 312 313 void UserScriptMaster::NewScriptsAvailable(base::SharedMemory* handle) { 314 // Ensure handle is deleted or released. 315 scoped_ptr<base::SharedMemory> handle_deleter(handle); 316 317 if (pending_scan_) { 318 // While we were scanning, there were further changes. Don't bother 319 // notifying about these scripts and instead just immediately rescan. 320 pending_scan_ = false; 321 StartScan(); 322 } else { 323 // We're no longer scanning. 324 script_reloader_ = NULL; 325 // We've got scripts ready to go. 326 shared_memory_.swap(handle_deleter); 327 328 NotificationService::current()->Notify( 329 NotificationType::USER_SCRIPTS_UPDATED, 330 Source<Profile>(profile_), 331 Details<base::SharedMemory>(handle)); 332 } 333 } 334 335 void UserScriptMaster::Observe(NotificationType type, 336 const NotificationSource& source, 337 const NotificationDetails& details) { 338 switch (type.value) { 339 case NotificationType::EXTENSIONS_READY: 340 extensions_service_ready_ = true; 341 StartScan(); 342 break; 343 case NotificationType::EXTENSION_LOADED: { 344 // Add any content scripts inside the extension. 345 const Extension* extension = Details<const Extension>(details).ptr(); 346 bool incognito_enabled = profile_->GetExtensionService()-> 347 IsIncognitoEnabled(extension->id()); 348 const UserScriptList& scripts = extension->content_scripts(); 349 for (UserScriptList::const_iterator iter = scripts.begin(); 350 iter != scripts.end(); ++iter) { 351 lone_scripts_.push_back(*iter); 352 lone_scripts_.back().set_incognito_enabled(incognito_enabled); 353 } 354 if (extensions_service_ready_) 355 StartScan(); 356 break; 357 } 358 case NotificationType::EXTENSION_UNLOADED: { 359 // Remove any content scripts. 360 const Extension* extension = 361 Details<UnloadedExtensionInfo>(details)->extension; 362 UserScriptList new_lone_scripts; 363 for (UserScriptList::iterator iter = lone_scripts_.begin(); 364 iter != lone_scripts_.end(); ++iter) { 365 if (iter->extension_id() != extension->id()) 366 new_lone_scripts.push_back(*iter); 367 } 368 lone_scripts_ = new_lone_scripts; 369 StartScan(); 370 371 // TODO(aa): Do we want to do something smarter for the scripts that have 372 // already been injected? 373 374 break; 375 } 376 case NotificationType::EXTENSION_USER_SCRIPTS_UPDATED: { 377 const Extension* extension = Details<const Extension>(details).ptr(); 378 UserScriptList new_lone_scripts; 379 bool incognito_enabled = profile_->GetExtensionService()-> 380 IsIncognitoEnabled(extension->id()); 381 for (UserScriptList::iterator iter = lone_scripts_.begin(); 382 iter != lone_scripts_.end(); ++iter) { 383 if (iter->extension_id() == extension->id()) { 384 iter->set_incognito_enabled(incognito_enabled); 385 } 386 } 387 StartScan(); 388 break; 389 } 390 391 default: 392 DCHECK(false); 393 } 394 } 395 396 void UserScriptMaster::StartScan() { 397 if (!script_reloader_) 398 script_reloader_ = new ScriptReloader(this); 399 400 script_reloader_->StartScan(user_script_dir_, lone_scripts_); 401 } 402