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