chrome/browser/enumerate_modules_model_win.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/enumerate_modules_model_win.h"
   6
   7 #include <Tlhelp32.h>
   8 #include <wintrust.h>
   9 #include <algorithm>
  10
  11 #include "base/bind.h"
  12 #include "base/command_line.h"
  13 #include "base/environment.h"
  14 #include "base/file_version_info_win.h"
  15 #include "base/files/file_path.h"
  16 #include "base/i18n/case_conversion.h"
  17 #include "base/metrics/histogram.h"
  18 #include "base/strings/string_number_conversions.h"
  19 #include "base/strings/string_util.h"
  20 #include "base/strings/utf_string_conversions.h"
  21 #include "base/time/time.h"
  22 #include "base/values.h"
  23 #include "base/version.h"
  24 #include "base/win/registry.h"
  25 #include "base/win/scoped_handle.h"
  26 #include "base/win/windows_version.h"
  27 #include "chrome/browser/chrome_notification_types.h"
  28 #include "chrome/browser/net/service_providers_win.h"
  29 #include "chrome/common/chrome_constants.h"
  30 #include "chrome/grit/generated_resources.h"
  31 #include "content/public/browser/notification_service.h"
  32 #include "crypto/sha2.h"
  33 #include "ui/base/l10n/l10n_util.h"
  34
  35 using content::BrowserThread;
  36
  37 // The period of time (in milliseconds) to wait until checking to see if any
  38 // incompatible modules exist.
  39 static const int kModuleCheckDelayMs = 45 * 1000;
  40
  41 // The path to the Shell Extension key in the Windows registry.
  42 static const wchar_t kRegPath[] =
  43     L"Software\\Microsoft\\Windows\\CurrentVersion\\Shell Extensions\\Approved";
  44
  45 // Short-hand for things on the blacklist you should simply get rid of.
  46 static const ModuleEnumerator::RecommendedAction kUninstallLink =
  47     static_cast<ModuleEnumerator::RecommendedAction>(
  48         ModuleEnumerator::UNINSTALL | ModuleEnumerator::SEE_LINK);
  49
  50 // Short-hand for things on the blacklist we are investigating and have info.
  51 static const ModuleEnumerator::RecommendedAction kInvestigatingLink =
  52     static_cast<ModuleEnumerator::RecommendedAction>(
  53         ModuleEnumerator::INVESTIGATING | ModuleEnumerator::SEE_LINK);
  54
  55 // A sort method that sorts by bad modules first, then by full name (including
  56 // path).
  57 static bool ModuleSort(const ModuleEnumerator::Module& a,
  58                        const ModuleEnumerator::Module& b) {
  59   if (a.status != b.status)
  60     return a.status > b.status;
  61
  62   if (a.location == b.location)
  63     return a.name < b.name;
  64
  65   return a.location < b.location;
  66 }
  67
  68 namespace {
  69
  70 // Used to protect the LoadedModuleVector which is accessed
  71 // from both the UI thread and the FILE thread.
  72 base::Lock* lock = NULL;
  73
  74 // A struct to help de-duping modules before adding them to the enumerated
  75 // modules vector.
  76 struct FindModule {
  77  public:
  78   explicit FindModule(const ModuleEnumerator::Module& x)
  79     : module(x) {}
  80   bool operator()(const ModuleEnumerator::Module& module_in) const {
  81     return (module.location == module_in.location) &&
  82            (module.name == module_in.name);
  83   }
  84
  85   const ModuleEnumerator::Module& module;
  86 };
  87
  88 // Returns the long path name given a short path name. A short path name is a
  89 // path that follows the 8.3 convention and has ~x in it. If the path is already
  90 // a long path name, the function returns the current path without modification.
  91 bool ConvertToLongPath(const base::string16& short_path,
  92                        base::string16* long_path) {
  93   wchar_t long_path_buf[MAX_PATH];
  94   DWORD return_value = GetLongPathName(short_path.c_str(), long_path_buf,
  95                                        MAX_PATH);
  96   if (return_value != 0 && return_value < MAX_PATH) {
  97     *long_path = long_path_buf;
  98     return true;
  99   }
 100
 101   return false;
 102 }
 103
 104 }  // namespace
 105
 106 ModuleEnumerator::Module::Module() {
 107 }
 108
 109 ModuleEnumerator::Module::Module(const Module& rhs) = default;
 110
 111 ModuleEnumerator::Module::Module(ModuleType type,
 112                                  ModuleStatus status,
 113                                  const base::string16& location,
 114                                  const base::string16& name,
 115                                  const base::string16& product_name,
 116                                  const base::string16& description,
 117                                  const base::string16& version,
 118                                  const base::string16& digital_signer,
 119                                  RecommendedAction recommended_action)
 120     : type(type),
 121       status(status),
 122       location(location),
 123       name(name),
 124       product_name(product_name),
 125       description(description),
 126       version(version),
 127       digital_signer(digital_signer),
 128       recommended_action(recommended_action),
 129       duplicate_count(0),
 130       normalized(false) {
 131 }
 132
 133 ModuleEnumerator::Module::~Module() {
 134 }
 135
 136 // The browser process module blacklist. This lists modules that are known
 137 // to cause compatibility issues within the browser process. When adding to this
 138 // list, make sure that all paths are lower-case, in long pathname form, end
 139 // with a slash and use environments variables (or just look at one of the
 140 // comments below and keep it consistent with that). When adding an entry with
 141 // an environment variable not currently used in the list below, make sure to
 142 // update the list in PreparePathMappings. Filename, Description/Signer, and
 143 // Location must be entered as hashes (see GenerateHash). Filename is mandatory.
 144 // Entries without any Description, Signer info, or Location will never be
 145 // marked as confirmed bad (only as suspicious).
 146 const ModuleEnumerator::BlacklistEntry ModuleEnumerator::kModuleBlacklist[] = {
 147   // NOTE: Please keep this list sorted by dll name, then location.
 148
 149   // Version 3.2.1.6 seems to be implicated in most cases (and 3.2.2.2 in some).
 150   // There is a more recent version available for download.
 151   // accelerator.dll, "%programfiles%\\speedbit video accelerator\\".
 152   { "7ba9402f", "c9132d48", "", "", "", ALL, kInvestigatingLink },
 153
 154   // apiqq0.dll, "%temp%\\".
 155   { "26134911", "59145acf", "", "", "", ALL, kUninstallLink },
 156
 157   // arking0.dll, "%systemroot%\\system32\\".
 158   { "f5d8f549", "23d01d5b", "", "", "", ALL, kUninstallLink },
 159
 160   // arking1.dll, "%systemroot%\\system32\\".
 161   { "c60ca062", "23d01d5b", "", "", "", ALL, kUninstallLink },
 162
 163   // aswjsflt.dll, "%ProgramFiles%\\avast software\\avast\\", "AVAST Software".
 164   // NOTE: The digital signature of the DLL is double null terminated.
 165   // Avast Antivirus prior to version 8.0 would kill the Chrome child process
 166   // when blocked from running.
 167   { "2ea5422a", "6b3a1b00", "a7db0e0c", "", "8.0", XP,
 168     static_cast<RecommendedAction>(UPDATE | SEE_LINK | NOTIFY_USER) },
 169
 170   // aswjsflt.dll, "%ProgramFiles%\\alwil software\\avast5\\", "AVAST Software".
 171   // NOTE: The digital signature of the DLL is double null terminated.
 172   // Avast Antivirus prior to version 8.0 would kill the Chrome child process
 173   // when blocked from running.
 174   { "2ea5422a", "d8686924", "a7db0e0c", "", "8.0", XP,
 175     static_cast<RecommendedAction>(UPDATE | SEE_LINK | NOTIFY_USER) },
 176
 177   // Said to belong to Killer NIC from BigFoot Networks (not verified). Versions
 178   // 6.0.0.7 and 6.0.0.10 implicated.
 179   // bfllr.dll, "%systemroot%\\system32\\".
 180   { "6bb57633", "23d01d5b", "", "", "", ALL, kInvestigatingLink },
 181
 182   // clickpotatolitesahook.dll, "". Different version each report.
 183   { "0396e037.dll", "", "", "", "", ALL, kUninstallLink },
 184
 185   // cvasds0.dll, "%temp%\\".
 186   { "5ce0037c", "59145acf", "", "", "", ALL, kUninstallLink },
 187
 188   // cwalsp.dll, "%systemroot%\\system32\\".
 189   { "e579a039", "23d01d5b", "", "", "", ALL, kUninstallLink },
 190
 191   // datamngr.dll (1), "%programfiles%\\searchqu toolbar\\datamngr\\".
 192   { "7add320b", "470a3da3", "", "", "", ALL, kUninstallLink },
 193
 194   // datamngr.dll (2), "%programfiles%\\windows searchqu toolbar\\".
 195   { "7add320b", "7a3c8be3", "", "", "", ALL, kUninstallLink },
 196
 197   // dsoqq0.dll, "%temp%\\".
 198   { "1c4df325", "59145acf", "", "", "", ALL, kUninstallLink },
 199
 200   // flt.dll, "%programfiles%\\tueagles\\".
 201   { "6d01f4a1", "7935e9c2", "", "", "", ALL, kUninstallLink },
 202
 203   // This looks like a malware edition of a Brazilian Bank plugin, sometimes
 204   // referred to as Malware.Banc.A.
 205   // gbieh.dll, "%programfiles%\\gbplugin\\".
 206   { "4cb4f2e3", "88e4a3b1", "", "", "", ALL, kUninstallLink },
 207
 208   // hblitesahook.dll. Each report has different version number in location.
 209   { "5d10b363", "", "", "", "", ALL, kUninstallLink },
 210
 211   // icf.dll, "%systemroot%\\system32\\".
 212   { "303825ed", "23d01d5b", "", "", "", ALL, INVESTIGATING },
 213
 214   // idmmbc.dll (IDM), "%systemroot%\\system32\\". See: http://crbug.com/26892/.
 215   { "b8dce5c3", "23d01d5b", "", "", "6.03", ALL,
 216       static_cast<RecommendedAction>(UPDATE | DISABLE) },
 217
 218   // imon.dll (NOD32), "%systemroot%\\system32\\". See: http://crbug.com/21715.
 219   { "8f42f22e", "23d01d5b", "", "", "4.0", ALL,
 220       static_cast<RecommendedAction>(UPDATE | DISABLE) },
 221
 222   // is3lsp.dll, "%commonprogramfiles%\\is3\\anti-spyware\\".
 223   { "7ffbdce9", "bc5673f2", "", "", "", ALL,
 224       static_cast<RecommendedAction>(UPDATE | DISABLE | SEE_LINK) },
 225
 226   // jsi.dll, "%programfiles%\\profilecraze\\".
 227   { "f9555eea", "e3548061", "", "", "", ALL, kUninstallLink },
 228
 229   // kernel.dll, "%programfiles%\\contentwatch\\internet protection\\modules\\".
 230   { "ead2768e", "4e61ce60", "", "", "", ALL, INVESTIGATING },
 231
 232   // mgking0.dll, "%systemroot%\\system32\\".
 233   { "d0893e38", "23d01d5b", "", "", "", ALL, kUninstallLink },
 234
 235   // mgking0.dll, "%temp%\\".
 236   { "d0893e38", "59145acf", "", "", "", ALL, kUninstallLink },
 237
 238   // mgking1.dll, "%systemroot%\\system32\\".
 239   { "3e837222", "23d01d5b", "", "", "", ALL, kUninstallLink },
 240
 241   // mgking1.dll, "%temp%\\".
 242   { "3e837222", "59145acf", "", "", "", ALL, kUninstallLink },
 243
 244   // mstcipha.ime, "%systemroot%\\system32\\".
 245   { "5523579e", "23d01d5b", "", "", "", ALL, INVESTIGATING },
 246
 247   // mwtsp.dll, "%systemroot%\\system32\\".
 248   { "9830bff6", "23d01d5b", "", "", "", ALL, kUninstallLink },
 249
 250   // nodqq0.dll, "%temp%\\".
 251   { "b86ce04d", "59145acf", "", "", "", ALL, kUninstallLink },
 252
 253   // nProtect GameGuard Anti-cheat system. Every report has a different
 254   // location, since it is installed into and run from a game folder. Various
 255   // versions implicated.
 256   // npggnt.des, no fixed location.
 257   { "f2c8790d", "", "", "", "", ALL, kInvestigatingLink },
 258
 259   // nvlsp.dll,
 260   // "%programfiles%\\nvidia corporation\\networkaccessmanager\\bin32\\".
 261   { "37f907e2", "3ad0ff23", "", "", "", ALL, INVESTIGATING },
 262
 263   // post0.dll, "%systemroot%\\system32\\".
 264   { "7405c0c8", "23d01d5b", "", "", "", ALL, kUninstallLink },
 265
 266   // questbrwsearch.dll, "%programfiles%\\questbrwsearch\\".
 267   { "0953ed09", "f0d5eeda", "", "", "", ALL, kUninstallLink },
 268
 269   // questscan.dll, "%programfiles%\\questscan\\".
 270   { "f4f3391e", "119d20f7", "", "", "", ALL, kUninstallLink },
 271
 272   // radhslib.dll (Naomi web filter), "%programfiles%\\rnamfler\\".
 273   // See http://crbug.com/12517.
 274   { "7edcd250", "0733dc3e", "", "", "", ALL, INVESTIGATING },
 275
 276   // rlls.dll, "%programfiles%\\relevantknowledge\\".
 277   { "a1ed94a7", "ea9d6b36", "", "", "", ALL, kUninstallLink },
 278
 279   // rooksdol.dll, "%programfiles%\\trusteer\\rapport\\bin\\".
 280   { "802aefef", "06120e13", "", "", "3.5.1008.40", ALL, UPDATE },
 281
 282   // scanquery.dll, "%programfiles%\\scanquery\\".
 283   { "0b52d2ae", "a4cc88b1", "", "", "", ALL, kUninstallLink },
 284
 285   // sdata.dll, "%programdata%\\srtserv\\".
 286   { "1936d5cc", "223c44be", "", "", "", ALL, kUninstallLink },
 287
 288   // searchtree.dll,
 289   // "%programfiles%\\contentwatch\\internet protection\\modules\\".
 290   { "f6915a31", "4e61ce60", "", "", "", ALL, INVESTIGATING },
 291
 292   // sgprxy.dll, "%commonprogramfiles%\\is3\\anti-spyware\\".
 293   { "005965ea", "bc5673f2", "", "", "", ALL, INVESTIGATING },
 294
 295   // snxhk.dll, "%ProgramFiles%\\avast software\\avast\\", "AVAST Software".
 296   // NOTE: The digital signature of the DLL is double null terminated.
 297   // Avast Antivirus prior to version 8.0 would kill the Chrome child process
 298   // when blocked from running.
 299   { "46c16aa8", "6b3a1b00", "a7db0e0c", "", "8.0", XP,
 300     static_cast<RecommendedAction>(UPDATE | SEE_LINK | NOTIFY_USER) },
 301
 302   // snxhk.dll, "%ProgramFiles%\\alwil software\\avast5\\", "AVAST Software".
 303   // NOTE: The digital signature of the DLL is double null terminated.
 304   // Avast Antivirus prior to version 8.0 would kill the Chrome child process
 305   // when blocked from running.
 306   { "46c16aa8", "d8686924", "a7db0e0c", "", "8.0", XP,
 307     static_cast<RecommendedAction>(UPDATE | SEE_LINK | NOTIFY_USER) },
 308
 309   // sprotector.dll, "". Different location each report.
 310   { "24555d74", "", "", "", "", ALL, kUninstallLink },
 311
 312   // swi_filter_0001.dll (Sophos Web Intelligence),
 313   // "%programfiles%\\sophos\\sophos anti-virus\\web intelligence\\".
 314   // A small random sample all showed version 1.0.5.0.
 315   { "61112d7b", "25fb120f", "", "", "", ALL, kInvestigatingLink },
 316
 317   // twking0.dll, "%systemroot%\\system32\\".
 318   { "0355549b", "23d01d5b", "", "", "", ALL, kUninstallLink },
 319
 320   // twking1.dll, "%systemroot%\\system32\\".
 321   { "02e44508", "23d01d5b", "", "", "", ALL, kUninstallLink },
 322
 323   // vksaver.dll, "%systemroot%\\system32\\".
 324   { "c4a784d5", "23d01d5b", "", "", "", ALL, kUninstallLink },
 325
 326   // vlsp.dll (Venturi Firewall?), "%systemroot%\\system32\\".
 327   { "2e4eb93d", "23d01d5b", "", "", "", ALL, INVESTIGATING },
 328
 329   // vmn3_1dn.dll, "%appdata%\\roaming\\vmndtxtb\\".
 330   { "bba2037d", "9ab68585", "", "", "", ALL, kUninstallLink },
 331
 332   // webanalyzer.dll,
 333   // "%programfiles%\\contentwatch\\internet protection\\modules\\".
 334   { "c70b697d", "4e61ce60", "", "", "", ALL, INVESTIGATING },
 335
 336   // wowst0.dll, "%systemroot%\\system32\\".
 337   { "38ad9963", "23d01d5b", "", "", "", ALL, kUninstallLink },
 338
 339   // wxbase28u_vc_cw.dll, "%systemroot%\\system32\\".
 340   { "e967210d", "23d01d5b", "", "", "", ALL, kUninstallLink },
 341 };
 342
 343 // Generates an 8 digit hash from the input given.
 344 static void GenerateHash(const std::string& input, std::string* output) {
 345   if (input.empty()) {
 346     *output = "";
 347     return;
 348   }
 349
 350   uint8 hash[4];
 351   crypto::SHA256HashString(input, hash, sizeof(hash));
 352   *output = base::StringToLowerASCII(base::HexEncode(hash, sizeof(hash)));
 353 }
 354
 355 // -----------------------------------------------------------------------------
 356
 357 // static
 358 void ModuleEnumerator::NormalizeModule(Module* module) {
 359   base::string16 path = module->location;
 360   if (!ConvertToLongPath(path, &module->location))
 361     module->location = path;
 362
 363   module->location = base::i18n::ToLower(module->location);
 364
 365   // Location contains the filename, so the last slash is where the path
 366   // ends.
 367   size_t last_slash = module->location.find_last_of(L"\\");
 368   if (last_slash != base::string16::npos) {
 369     module->name = module->location.substr(last_slash + 1);
 370     module->location = module->location.substr(0, last_slash + 1);
 371   } else {
 372     module->name = module->location;
 373     module->location.clear();
 374   }
 375
 376   // Some version strings have things like (win7_rtm.090713-1255) appended
 377   // to them. Remove that.
 378   size_t first_space = module->version.find_first_of(L" ");
 379   if (first_space != base::string16::npos)
 380     module->version = module->version.substr(0, first_space);
 381
 382   module->normalized = true;
 383 }
 384
 385 // static
 386 ModuleEnumerator::ModuleStatus ModuleEnumerator::Match(
 387     const ModuleEnumerator::Module& module,
 388     const ModuleEnumerator::BlacklistEntry& blacklisted) {
 389   // All modules must be normalized before matching against blacklist.
 390   DCHECK(module.normalized);
 391   // Filename is mandatory and version should not contain spaces.
 392   DCHECK(strlen(blacklisted.filename) > 0);
 393   DCHECK(!strstr(blacklisted.version_from, " "));
 394   DCHECK(!strstr(blacklisted.version_to, " "));
 395
 396   base::win::Version version = base::win::GetVersion();
 397   switch (version) {
 398      case base::win::VERSION_XP:
 399       if (!(blacklisted.os & XP)) return NOT_MATCHED;
 400       break;
 401     default:
 402       break;
 403   }
 404
 405   std::string filename_hash, location_hash;
 406   GenerateHash(base::WideToUTF8(module.name), &filename_hash);
 407   GenerateHash(base::WideToUTF8(module.location), &location_hash);
 408
 409   // Filenames are mandatory. Location is mandatory if given.
 410   if (filename_hash == blacklisted.filename &&
 411           (std::string(blacklisted.location).empty() ||
 412           location_hash == blacklisted.location)) {
 413     // We have a name match against the blacklist (and possibly location match
 414     // also), so check version.
 415     Version module_version(base::UTF16ToASCII(module.version));
 416     Version version_min(blacklisted.version_from);
 417     Version version_max(blacklisted.version_to);
 418     bool version_ok = !version_min.IsValid() && !version_max.IsValid();
 419     if (!version_ok) {
 420       bool too_low = version_min.IsValid() &&
 421           (!module_version.IsValid() ||
 422           module_version.CompareTo(version_min) < 0);
 423       bool too_high = version_max.IsValid() &&
 424           (!module_version.IsValid() ||
 425           module_version.CompareTo(version_max) >= 0);
 426       version_ok = !too_low && !too_high;
 427     }
 428
 429     if (version_ok) {
 430       // At this point, the names match and there is no version specified
 431       // or the versions also match.
 432
 433       std::string desc_or_signer(blacklisted.desc_or_signer);
 434       std::string signer_hash, description_hash;
 435       GenerateHash(base::WideToUTF8(module.digital_signer), &signer_hash);
 436       GenerateHash(base::WideToUTF8(module.description), &description_hash);
 437
 438       // If signatures match (or both are empty), then we have a winner.
 439       if (signer_hash == desc_or_signer)
 440         return CONFIRMED_BAD;
 441
 442       // If descriptions match (or both are empty) and the locations match, then
 443       // we also have a confirmed match.
 444       if (description_hash == desc_or_signer &&
 445           !location_hash.empty() && location_hash == blacklisted.location)
 446         return CONFIRMED_BAD;
 447
 448       // We are not sure, but it is likely bad.
 449       return SUSPECTED_BAD;
 450     }
 451   }
 452
 453   return NOT_MATCHED;
 454 }
 455
 456 ModuleEnumerator::ModuleEnumerator(EnumerateModulesModel* observer)
 457     : enumerated_modules_(NULL),
 458       observer_(observer),
 459       limited_mode_(false),
 460       callback_thread_id_(BrowserThread::ID_COUNT) {
 461 }
 462
 463 void ModuleEnumerator::ScanNow(ModulesVector* list, bool limited_mode) {
 464   enumerated_modules_ = list;
 465
 466   limited_mode_ = limited_mode;
 467
 468   if (!limited_mode_) {
 469     CHECK(BrowserThread::GetCurrentThreadIdentifier(&callback_thread_id_));
 470     BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE,
 471                             base::Bind(&ModuleEnumerator::ScanImpl, this));
 472   } else {
 473     // Run it synchronously.
 474     ScanImpl();
 475   }
 476 }
 477
 478 ModuleEnumerator::~ModuleEnumerator() {
 479 }
 480
 481 void ModuleEnumerator::ScanImpl() {
 482   base::TimeTicks start_time = base::TimeTicks::Now();
 483
 484   enumerated_modules_->clear();
 485
 486   // Make sure the path mapping vector is setup so we can collapse paths.
 487   PreparePathMappings();
 488
 489   // Enumerating loaded modules must happen first since the other types of
 490   // modules check for duplication against the loaded modules.
 491   base::TimeTicks checkpoint = base::TimeTicks::Now();
 492   EnumerateLoadedModules();
 493   base::TimeTicks checkpoint2 = base::TimeTicks::Now();
 494   UMA_HISTOGRAM_TIMES("Conflicts.EnumerateLoadedModules",
 495                       checkpoint2 - checkpoint);
 496
 497   checkpoint = checkpoint2;
 498   EnumerateShellExtensions();
 499   checkpoint2 = base::TimeTicks::Now();
 500   UMA_HISTOGRAM_TIMES("Conflicts.EnumerateShellExtensions",
 501                       checkpoint2 - checkpoint);
 502
 503   checkpoint = checkpoint2;
 504   EnumerateWinsockModules();
 505   checkpoint2 = base::TimeTicks::Now();
 506   UMA_HISTOGRAM_TIMES("Conflicts.EnumerateWinsockModules",
 507                       checkpoint2 - checkpoint);
 508
 509   MatchAgainstBlacklist();
 510
 511   std::sort(enumerated_modules_->begin(),
 512             enumerated_modules_->end(), ModuleSort);
 513
 514   if (!limited_mode_) {
 515     // Send a reply back on the UI thread.
 516     BrowserThread::PostTask(callback_thread_id_, FROM_HERE,
 517                             base::Bind(&ModuleEnumerator::ReportBack, this));
 518   } else {
 519     // We are on the main thread already.
 520     ReportBack();
 521   }
 522
 523   UMA_HISTOGRAM_TIMES("Conflicts.EnumerationTotalTime",
 524                       base::TimeTicks::Now() - start_time);
 525 }
 526
 527 void ModuleEnumerator::EnumerateLoadedModules() {
 528   // Get all modules in the current process.
 529   base::win::ScopedHandle snap(::CreateToolhelp32Snapshot(TH32CS_SNAPMODULE,
 530                                ::GetCurrentProcessId()));
 531   if (!snap.Get())
 532     return;
 533
 534   // Walk the module list.
 535   MODULEENTRY32 module = { sizeof(module) };
 536   if (!::Module32First(snap.Get(), &module))
 537     return;
 538
 539   do {
 540     // It would be weird to present chrome.exe as a loaded module.
 541     if (_wcsicmp(chrome::kBrowserProcessExecutableName, module.szModule) == 0)
 542       continue;
 543
 544     Module entry;
 545     entry.type = LOADED_MODULE;
 546     entry.location = module.szExePath;
 547     PopulateModuleInformation(&entry);
 548
 549     NormalizeModule(&entry);
 550     CollapsePath(&entry);
 551     enumerated_modules_->push_back(entry);
 552   } while (::Module32Next(snap.Get(), &module));
 553 }
 554
 555 void ModuleEnumerator::EnumerateShellExtensions() {
 556   ReadShellExtensions(HKEY_LOCAL_MACHINE);
 557   ReadShellExtensions(HKEY_CURRENT_USER);
 558 }
 559
 560 void ModuleEnumerator::ReadShellExtensions(HKEY parent) {
 561   base::win::RegistryValueIterator registration(parent, kRegPath);
 562   while (registration.Valid()) {
 563     std::wstring key(std::wstring(L"CLSID\\") + registration.Name() +
 564         L"\\InProcServer32");
 565     base::win::RegKey clsid;
 566     if (clsid.Open(HKEY_CLASSES_ROOT, key.c_str(), KEY_READ) != ERROR_SUCCESS) {
 567       ++registration;
 568       continue;
 569     }
 570     base::string16 dll;
 571     if (clsid.ReadValue(L"", &dll) != ERROR_SUCCESS) {
 572       ++registration;
 573       continue;
 574     }
 575     clsid.Close();
 576
 577     Module entry;
 578     entry.type = SHELL_EXTENSION;
 579     entry.location = dll;
 580     PopulateModuleInformation(&entry);
 581
 582     NormalizeModule(&entry);
 583     CollapsePath(&entry);
 584     AddToListWithoutDuplicating(entry);
 585
 586     ++registration;
 587   }
 588 }
 589
 590 void ModuleEnumerator::EnumerateWinsockModules() {
 591   // Add to this list the Winsock LSP DLLs.
 592   WinsockLayeredServiceProviderList layered_providers;
 593   GetWinsockLayeredServiceProviders(&layered_providers);
 594   for (size_t i = 0; i < layered_providers.size(); ++i) {
 595     Module entry;
 596     entry.type = WINSOCK_MODULE_REGISTRATION;
 597     entry.status = NOT_MATCHED;
 598     entry.normalized = false;
 599     entry.location = layered_providers[i].path;
 600     entry.description = layered_providers[i].name;
 601     entry.recommended_action = NONE;
 602     entry.duplicate_count = 0;
 603
 604     wchar_t expanded[MAX_PATH];
 605     DWORD size = ExpandEnvironmentStrings(
 606         entry.location.c_str(), expanded, MAX_PATH);
 607     if (size != 0 && size <= MAX_PATH) {
 608       entry.digital_signer =
 609           GetSubjectNameFromDigitalSignature(base::FilePath(expanded));
 610     }
 611     entry.version = base::IntToString16(layered_providers[i].version);
 612
 613     // Paths have already been collapsed.
 614     NormalizeModule(&entry);
 615     AddToListWithoutDuplicating(entry);
 616   }
 617 }
 618
 619 void ModuleEnumerator::PopulateModuleInformation(Module* module) {
 620   module->status = NOT_MATCHED;
 621   module->duplicate_count = 0;
 622   module->normalized = false;
 623   module->digital_signer =
 624       GetSubjectNameFromDigitalSignature(base::FilePath(module->location));
 625   module->recommended_action = NONE;
 626   scoped_ptr<FileVersionInfo> version_info(
 627       FileVersionInfo::CreateFileVersionInfo(base::FilePath(module->location)));
 628   if (version_info.get()) {
 629     FileVersionInfoWin* version_info_win =
 630         static_cast<FileVersionInfoWin*>(version_info.get());
 631
 632     VS_FIXEDFILEINFO* fixed_file_info = version_info_win->fixed_file_info();
 633     if (fixed_file_info) {
 634       module->description = version_info_win->file_description();
 635       module->version = version_info_win->file_version();
 636       module->product_name = version_info_win->product_name();
 637     }
 638   }
 639 }
 640
 641 void ModuleEnumerator::AddToListWithoutDuplicating(const Module& module) {
 642   DCHECK(module.normalized);
 643   // These are registered modules, not loaded modules so the same module
 644   // can be registered multiple times, often dozens of times. There is no need
 645   // to list each registration, so we just increment the count for each module
 646   // that is counted multiple times.
 647   ModulesVector::iterator iter;
 648   iter = std::find_if(enumerated_modules_->begin(),
 649                       enumerated_modules_->end(),
 650                       FindModule(module));
 651   if (iter != enumerated_modules_->end()) {
 652     iter->duplicate_count++;
 653     iter->type = static_cast<ModuleType>(iter->type | module.type);
 654   } else {
 655     enumerated_modules_->push_back(module);
 656   }
 657 }
 658
 659 void ModuleEnumerator::PreparePathMappings() {
 660   path_mapping_.clear();
 661
 662   scoped_ptr<base::Environment> environment(base::Environment::Create());
 663   std::vector<base::string16> env_vars;
 664   env_vars.push_back(L"LOCALAPPDATA");
 665   env_vars.push_back(L"ProgramFiles");
 666   env_vars.push_back(L"ProgramData");
 667   env_vars.push_back(L"USERPROFILE");
 668   env_vars.push_back(L"SystemRoot");
 669   env_vars.push_back(L"TEMP");
 670   env_vars.push_back(L"TMP");
 671   env_vars.push_back(L"CommonProgramFiles");
 672   for (std::vector<base::string16>::const_iterator variable = env_vars.begin();
 673        variable != env_vars.end(); ++variable) {
 674     std::string path;
 675     if (environment->GetVar(base::UTF16ToASCII(*variable).c_str(), &path)) {
 676       path_mapping_.push_back(
 677           std::make_pair(base::i18n::ToLower(base::UTF8ToUTF16(path)) + L"\\",
 678                          L"%" + base::i18n::ToLower(*variable) + L"%"));
 679     }
 680   }
 681 }
 682
 683 void ModuleEnumerator::CollapsePath(Module* entry) {
 684   // Take the path and see if we can use any of the substitution values
 685   // from the vector constructed above to replace c:\windows with, for
 686   // example, %systemroot%. The most collapsed path (the one with the
 687   // minimum length) wins.
 688   size_t min_length = MAXINT;
 689   base::string16 location = entry->location;
 690   for (PathMapping::const_iterator mapping = path_mapping_.begin();
 691        mapping != path_mapping_.end(); ++mapping) {
 692     base::string16 prefix = mapping->first;
 693     if (base::StartsWith(location, prefix, false)) {
 694       base::string16 new_location = mapping->second +
 695                               location.substr(prefix.length() - 1);
 696       size_t length = new_location.length() - mapping->second.length();
 697       if (length < min_length) {
 698         entry->location = new_location;
 699         min_length = length;
 700       }
 701     }
 702   }
 703 }
 704
 705 void ModuleEnumerator::MatchAgainstBlacklist() {
 706   for (size_t m = 0; m < enumerated_modules_->size(); ++m) {
 707     // Match this module against the blacklist.
 708     Module* module = &(*enumerated_modules_)[m];
 709     module->status = GOOD;  // We change this below potentially.
 710     for (size_t i = 0; i < arraysize(kModuleBlacklist); ++i) {
 711       #if !defined(NDEBUG)
 712         // This saves time when constructing the blacklist.
 713         std::string hashes(kModuleBlacklist[i].filename);
 714         std::string hash1, hash2, hash3;
 715         GenerateHash(kModuleBlacklist[i].filename, &hash1);
 716         hashes += " - " + hash1;
 717         GenerateHash(kModuleBlacklist[i].location, &hash2);
 718         hashes += " - " + hash2;
 719         GenerateHash(kModuleBlacklist[i].desc_or_signer, &hash3);
 720         hashes += " - " + hash3;
 721       #endif
 722
 723       ModuleStatus status = Match(*module, kModuleBlacklist[i]);
 724       if (status != NOT_MATCHED) {
 725         // We have a match against the blacklist. Mark it as such.
 726         module->status = status;
 727         module->recommended_action = kModuleBlacklist[i].help_tip;
 728         break;
 729       }
 730     }
 731
 732     // Modules loaded from these locations are frequently malicious
 733     // and notorious for changing frequently so they are not good candidates
 734     // for blacklisting individually. Mark them as suspicious if we haven't
 735     // classified them as bad yet.
 736     if (module->status == NOT_MATCHED || module->status == GOOD) {
 737       if (base::StartsWith(module->location, L"%temp%", false) ||
 738           base::StartsWith(module->location, L"%tmp%", false)) {
 739         module->status = SUSPECTED_BAD;
 740       }
 741     }
 742   }
 743 }
 744
 745 void ModuleEnumerator::ReportBack() {
 746   if (!limited_mode_)
 747     DCHECK(BrowserThread::CurrentlyOn(callback_thread_id_));
 748   observer_->DoneScanning();
 749 }
 750
 751 base::string16 ModuleEnumerator::GetSubjectNameFromDigitalSignature(
 752     const base::FilePath& filename) {
 753   HCERTSTORE store = NULL;
 754   HCRYPTMSG message = NULL;
 755
 756   // Find the crypto message for this filename.
 757   bool result = !!CryptQueryObject(CERT_QUERY_OBJECT_FILE,
 758                                    filename.value().c_str(),
 759                                    CERT_QUERY_CONTENT_FLAG_PKCS7_SIGNED_EMBED,
 760                                    CERT_QUERY_FORMAT_FLAG_BINARY,
 761                                    0,
 762                                    NULL,
 763                                    NULL,
 764                                    NULL,
 765                                    &store,
 766                                    &message,
 767                                    NULL);
 768   if (!result)
 769     return base::string16();
 770
 771   // Determine the size of the signer info data.
 772   DWORD signer_info_size = 0;
 773   result = !!CryptMsgGetParam(message,
 774                               CMSG_SIGNER_INFO_PARAM,
 775                               0,
 776                               NULL,
 777                               &signer_info_size);
 778   if (!result)
 779     return base::string16();
 780
 781   // Allocate enough space to hold the signer info.
 782   scoped_ptr<BYTE[]> signer_info_buffer(new BYTE[signer_info_size]);
 783   CMSG_SIGNER_INFO* signer_info =
 784       reinterpret_cast<CMSG_SIGNER_INFO*>(signer_info_buffer.get());
 785
 786   // Obtain the signer info.
 787   result = !!CryptMsgGetParam(message,
 788                               CMSG_SIGNER_INFO_PARAM,
 789                               0,
 790                               signer_info,
 791                               &signer_info_size);
 792   if (!result)
 793     return base::string16();
 794
 795   // Search for the signer certificate.
 796   CERT_INFO CertInfo = {0};
 797   PCCERT_CONTEXT cert_context = NULL;
 798   CertInfo.Issuer = signer_info->Issuer;
 799   CertInfo.SerialNumber = signer_info->SerialNumber;
 800
 801   cert_context = CertFindCertificateInStore(
 802       store,
 803       X509_ASN_ENCODING | PKCS_7_ASN_ENCODING,
 804       0,
 805       CERT_FIND_SUBJECT_CERT,
 806       &CertInfo,
 807       NULL);
 808   if (!cert_context)
 809     return base::string16();
 810
 811   // Determine the size of the Subject name.
 812   DWORD subject_name_size = CertGetNameString(
 813       cert_context, CERT_NAME_SIMPLE_DISPLAY_TYPE, 0, NULL, NULL, 0);
 814   if (!subject_name_size)
 815     return base::string16();
 816
 817   base::string16 subject_name;
 818   subject_name.resize(subject_name_size);
 819
 820   // Get subject name.
 821   if (!(CertGetNameString(cert_context,
 822                           CERT_NAME_SIMPLE_DISPLAY_TYPE,
 823                           0,
 824                           NULL,
 825                           const_cast<LPWSTR>(subject_name.c_str()),
 826                           subject_name_size))) {
 827     return base::string16();
 828   }
 829
 830   return subject_name;
 831 }
 832
 833 //  ----------------------------------------------------------------------------
 834
 835 // static
 836 EnumerateModulesModel* EnumerateModulesModel::GetInstance() {
 837   return Singleton<EnumerateModulesModel>::get();
 838 }
 839
 840 bool EnumerateModulesModel::ShouldShowConflictWarning() const {
 841   // If the user has acknowledged the conflict notification, then we don't need
 842   // to show it again (because the scanning only happens once per the lifetime
 843   // of the process). If we were to run the scanning more than once, then we'd
 844   // need to clear the flag somewhere when we are ready to show it again.
 845   if (conflict_notification_acknowledged_)
 846     return false;
 847
 848   return confirmed_bad_modules_detected_ > 0;
 849 }
 850
 851 void EnumerateModulesModel::AcknowledgeConflictNotification() {
 852   if (!conflict_notification_acknowledged_) {
 853     conflict_notification_acknowledged_ = true;
 854     content::NotificationService::current()->Notify(
 855         chrome::NOTIFICATION_MODULE_INCOMPATIBILITY_BADGE_CHANGE,
 856         content::Source<EnumerateModulesModel>(this),
 857         content::NotificationService::NoDetails());
 858   }
 859 }
 860
 861 void EnumerateModulesModel::ScanNow() {
 862   if (scanning_)
 863     return;  // A scan is already in progress.
 864
 865   lock->Acquire();  // Balanced in DoneScanning();
 866
 867   scanning_ = true;
 868
 869   // Instruct the ModuleEnumerator class to load this on the File thread.
 870   // ScanNow does not block.
 871   if (!module_enumerator_.get())
 872     module_enumerator_ = new ModuleEnumerator(this);
 873   module_enumerator_->ScanNow(&enumerated_modules_, limited_mode_);
 874 }
 875
 876 base::ListValue* EnumerateModulesModel::GetModuleList() const {
 877   if (scanning_)
 878     return NULL;
 879
 880   lock->Acquire();
 881
 882   if (enumerated_modules_.empty()) {
 883     lock->Release();
 884     return NULL;
 885   }
 886
 887   base::ListValue* list = new base::ListValue();
 888
 889   for (ModuleEnumerator::ModulesVector::const_iterator module =
 890            enumerated_modules_.begin();
 891        module != enumerated_modules_.end(); ++module) {
 892     base::DictionaryValue* data = new base::DictionaryValue();
 893     data->SetInteger("type", module->type);
 894     base::string16 type_string;
 895     if ((module->type & ModuleEnumerator::LOADED_MODULE) == 0) {
 896       // Module is not loaded, denote type of module.
 897       if (module->type & ModuleEnumerator::SHELL_EXTENSION)
 898         type_string = L"Shell Extension";
 899       if (module->type & ModuleEnumerator::WINSOCK_MODULE_REGISTRATION) {
 900         if (!type_string.empty())
 901           type_string += L", ";
 902         type_string += L"Winsock";
 903       }
 904       // Must be one of the above type.
 905       DCHECK(!type_string.empty());
 906       if (!limited_mode_) {
 907         type_string += L" -- ";
 908         type_string += l10n_util::GetStringUTF16(IDS_CONFLICTS_NOT_LOADED_YET);
 909       }
 910     }
 911     data->SetString("type_description", type_string);
 912     data->SetInteger("status", module->status);
 913     data->SetString("location", module->location);
 914     data->SetString("name", module->name);
 915     data->SetString("product_name", module->product_name);
 916     data->SetString("description", module->description);
 917     data->SetString("version", module->version);
 918     data->SetString("digital_signer", module->digital_signer);
 919
 920     if (!limited_mode_) {
 921       // Figure out the possible resolution help string.
 922       base::string16 actions;
 923       base::string16 separator = L" " +
 924           l10n_util::GetStringUTF16(
 925               IDS_CONFLICTS_CHECK_POSSIBLE_ACTION_SEPARATOR) +
 926           L" ";
 927
 928       if (module->recommended_action & ModuleEnumerator::INVESTIGATING) {
 929         actions = l10n_util::GetStringUTF16(
 930             IDS_CONFLICTS_CHECK_INVESTIGATING);
 931       } else {
 932         if (module->recommended_action & ModuleEnumerator::UNINSTALL) {
 933           if (!actions.empty())
 934             actions += separator;
 935           actions = l10n_util::GetStringUTF16(
 936               IDS_CONFLICTS_CHECK_POSSIBLE_ACTION_UNINSTALL);
 937         }
 938         if (module->recommended_action & ModuleEnumerator::UPDATE) {
 939           if (!actions.empty())
 940             actions += separator;
 941           actions += l10n_util::GetStringUTF16(
 942               IDS_CONFLICTS_CHECK_POSSIBLE_ACTION_UPDATE);
 943         }
 944         if (module->recommended_action & ModuleEnumerator::DISABLE) {
 945           if (!actions.empty())
 946             actions += separator;
 947           actions += l10n_util::GetStringUTF16(
 948               IDS_CONFLICTS_CHECK_POSSIBLE_ACTION_DISABLE);
 949         }
 950       }
 951       base::string16 possible_resolution;
 952       if (!actions.empty()) {
 953         possible_resolution =
 954             l10n_util::GetStringUTF16(IDS_CONFLICTS_CHECK_POSSIBLE_ACTIONS) +
 955             L" " + actions;
 956       }
 957       data->SetString("possibleResolution", possible_resolution);
 958       data->SetString("help_url",
 959                       ConstructHelpCenterUrl(*module).spec().c_str());
 960     }
 961
 962     list->Append(data);
 963   }
 964
 965   lock->Release();
 966   return list;
 967 }
 968
 969 GURL EnumerateModulesModel::GetFirstNotableConflict() {
 970   lock->Acquire();
 971   GURL url;
 972
 973   if (enumerated_modules_.empty()) {
 974     lock->Release();
 975     return GURL();
 976   }
 977
 978   for (ModuleEnumerator::ModulesVector::const_iterator module =
 979            enumerated_modules_.begin();
 980        module != enumerated_modules_.end(); ++module) {
 981     if (!(module->recommended_action & ModuleEnumerator::NOTIFY_USER))
 982       continue;
 983
 984     url = ConstructHelpCenterUrl(*module);
 985     DCHECK(url.is_valid());
 986     break;
 987   }
 988
 989   lock->Release();
 990   return url;
 991 }
 992
 993
 994 EnumerateModulesModel::EnumerateModulesModel()
 995     : limited_mode_(false),
 996       scanning_(false),
 997       conflict_notification_acknowledged_(false),
 998       confirmed_bad_modules_detected_(0),
 999       suspected_bad_modules_detected_(0),
1000       modules_to_notify_about_(0) {
1001   lock = new base::Lock();
1002 }
1003
1004 EnumerateModulesModel::~EnumerateModulesModel() {
1005   delete lock;
1006 }
1007
1008 void EnumerateModulesModel::MaybePostScanningTask() {
1009   static bool done = false;
1010   if (!done) {
1011     done = true;
1012     if (base::win::GetVersion() == base::win::VERSION_XP) {
1013       check_modules_timer_.Start(FROM_HERE,
1014           base::TimeDelta::FromMilliseconds(kModuleCheckDelayMs),
1015           this, &EnumerateModulesModel::ScanNow);
1016     }
1017   }
1018 }
1019
1020 void EnumerateModulesModel::DoneScanning() {
1021   confirmed_bad_modules_detected_ = 0;
1022   suspected_bad_modules_detected_ = 0;
1023   modules_to_notify_about_ = 0;
1024   for (ModuleEnumerator::ModulesVector::const_iterator module =
1025        enumerated_modules_.begin();
1026        module != enumerated_modules_.end(); ++module) {
1027     if (module->status == ModuleEnumerator::CONFIRMED_BAD) {
1028       ++confirmed_bad_modules_detected_;
1029       if (module->recommended_action & ModuleEnumerator::NOTIFY_USER)
1030         ++modules_to_notify_about_;
1031     } else if (module->status == ModuleEnumerator::SUSPECTED_BAD) {
1032       ++suspected_bad_modules_detected_;
1033       if (module->recommended_action & ModuleEnumerator::NOTIFY_USER)
1034         ++modules_to_notify_about_;
1035     }
1036   }
1037
1038   scanning_ = false;
1039   lock->Release();
1040
1041   UMA_HISTOGRAM_COUNTS_100("Conflicts.SuspectedBadModules",
1042                            suspected_bad_modules_detected_);
1043   UMA_HISTOGRAM_COUNTS_100("Conflicts.ConfirmedBadModules",
1044                            confirmed_bad_modules_detected_);
1045
1046   // Notifications are not available in limited mode.
1047   if (limited_mode_)
1048     return;
1049
1050   content::NotificationService::current()->Notify(
1051       chrome::NOTIFICATION_MODULE_LIST_ENUMERATED,
1052       content::Source<EnumerateModulesModel>(this),
1053       content::NotificationService::NoDetails());
1054 }
1055
1056 GURL EnumerateModulesModel::ConstructHelpCenterUrl(
1057     const ModuleEnumerator::Module& module) const {
1058   if (!(module.recommended_action & ModuleEnumerator::SEE_LINK) &&
1059       !(module.recommended_action & ModuleEnumerator::NOTIFY_USER))
1060     return GURL();
1061
1062   // Construct the needed hashes.
1063   std::string filename, location, description, signer;
1064   GenerateHash(base::WideToUTF8(module.name), &filename);
1065   GenerateHash(base::WideToUTF8(module.location), &location);
1066   GenerateHash(base::WideToUTF8(module.description), &description);
1067   GenerateHash(base::WideToUTF8(module.digital_signer), &signer);
1068
1069   base::string16 url =
1070       l10n_util::GetStringFUTF16(IDS_HELP_CENTER_VIEW_CONFLICTS,
1071           base::ASCIIToUTF16(filename), base::ASCIIToUTF16(location),
1072           base::ASCIIToUTF16(description), base::ASCIIToUTF16(signer));
1073   return GURL(base::UTF16ToUTF8(url));
1074 }