components/policy/core/common/policy_loader_win.cc

   1 // Copyright (c) 2014 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 "components/policy/core/common/policy_loader_win.h"
   6
   7 #include <windows.h>
   8 #include <lm.h>       // For limits.
   9 #include <ntdsapi.h>  // For Ds[Un]Bind
  10 #include <rpc.h>      // For struct GUID
  11 #include <shlwapi.h>  // For PathIsUNC()
  12 #include <userenv.h>  // For GPO functions
  13
  14 #include <string>
  15 #include <vector>
  16
  17 // shlwapi.dll is required for PathIsUNC().
  18 #pragma comment(lib, "shlwapi.lib")
  19 // userenv.dll is required for various GPO functions.
  20 #pragma comment(lib, "userenv.lib")
  21 // ntdsapi.dll is required for Ds[Un]Bind calls.
  22 #pragma comment(lib, "ntdsapi.lib")
  23
  24 #include "base/basictypes.h"
  25 #include "base/bind.h"
  26 #include "base/files/file_util.h"
  27 #include "base/json/json_reader.h"
  28 #include "base/json/json_writer.h"
  29 #include "base/lazy_instance.h"
  30 #include "base/logging.h"
  31 #include "base/memory/scoped_ptr.h"
  32 #include "base/metrics/histogram.h"
  33 #include "base/metrics/sparse_histogram.h"
  34 #include "base/scoped_native_library.h"
  35 #include "base/sequenced_task_runner.h"
  36 #include "base/stl_util.h"
  37 #include "base/strings/string16.h"
  38 #include "base/strings/string_util.h"
  39 #include "base/values.h"
  40 #include "base/win/win_util.h"
  41 #include "base/win/windows_version.h"
  42 #include "components/json_schema/json_schema_constants.h"
  43 #include "components/policy/core/common/policy_bundle.h"
  44 #include "components/policy/core/common/policy_load_status.h"
  45 #include "components/policy/core/common/policy_map.h"
  46 #include "components/policy/core/common/policy_namespace.h"
  47 #include "components/policy/core/common/preg_parser_win.h"
  48 #include "components/policy/core/common/registry_dict_win.h"
  49 #include "components/policy/core/common/schema.h"
  50 #include "policy/policy_constants.h"
  51
  52 namespace schema = json_schema_constants;
  53
  54 namespace policy {
  55
  56 namespace {
  57
  58 const char kKeyMandatory[] = "policy";
  59 const char kKeyRecommended[] = "recommended";
  60 const char kKeySchema[] = "schema";
  61 const char kKeyThirdParty[] = "3rdparty";
  62
  63 // The Legacy Browser Support was the first user of the policy-for-extensions
  64 // API, and relied on behavior that will be phased out. If this extension is
  65 // present then its policies will be loaded in a special way.
  66 // TODO(joaodasilva): remove this for M35. http://crbug.com/325349
  67 const char kLegacyBrowserSupportExtensionId[] =
  68     "heildphpnddilhkemkielfhnkaagiabh";
  69
  70 // The web store url that is the only trusted source for extensions.
  71 const char kExpectedWebStoreUrl[] =
  72     ";https://clients2.google.com/service/update2/crx";
  73 // String to be prepended to each blocked entry.
  74 const char kBlockedExtensionPrefix[] = "[BLOCKED]";
  75
  76 // List of policies that are considered only if the user is part of a AD domain.
  77 // Please document any new additions in policy_templates.json!
  78 const char* kInsecurePolicies[] = {
  79     key::kMetricsReportingEnabled,
  80     key::kDefaultSearchProviderEnabled,
  81     key::kHomepageIsNewTabPage,
  82     key::kHomepageLocation,
  83     key::kRestoreOnStartup,
  84     key::kRestoreOnStartupURLs
  85 };
  86
  87 // The GUID of the registry settings group policy extension.
  88 GUID kRegistrySettingsCSEGUID = REGISTRY_EXTENSION_GUID;
  89
  90 // The list of possible errors that can occur while collecting information about
  91 // the current enterprise environment.
  92 // This enum is used to define the buckets for an enumerated UMA histogram.
  93 // Hence,
  94 //   (a) existing enumerated constants should never be deleted or reordered, and
  95 //   (b) new constants should only be appended at the end of the enumeration.
  96 enum DomainCheckErrors {
  97   DOMAIN_CHECK_ERROR_GET_JOIN_INFO = 0,
  98   DOMAIN_CHECK_ERROR_DS_BIND = 1,
  99   DOMAIN_CHECK_ERROR_SIZE,  // Not a DomainCheckError.  Must be last.
 100 };
 101
 102 // If the LBS extension is found and contains a schema in the registry then this
 103 // function is used to patch it, and make it compliant. The fix is to
 104 // add an "items" attribute to lists that don't declare it.
 105 std::string PatchSchema(const std::string& schema) {
 106   base::JSONParserOptions options = base::JSON_PARSE_RFC;
 107   scoped_ptr<base::Value> json(base::JSONReader::Read(schema, options));
 108   base::DictionaryValue* dict = NULL;
 109   base::DictionaryValue* properties = NULL;
 110   if (!json ||
 111       !json->GetAsDictionary(&dict) ||
 112       !dict->GetDictionary(schema::kProperties, &properties)) {
 113     return schema;
 114   }
 115
 116   for (base::DictionaryValue::Iterator it(*properties);
 117        !it.IsAtEnd(); it.Advance()) {
 118     base::DictionaryValue* policy_schema = NULL;
 119     std::string type;
 120     if (properties->GetDictionary(it.key(), &policy_schema) &&
 121         policy_schema->GetString(schema::kType, &type) &&
 122         type == schema::kArray &&
 123         !policy_schema->HasKey(schema::kItems)) {
 124       scoped_ptr<base::DictionaryValue> items(new base::DictionaryValue());
 125       items->SetString(schema::kType, schema::kString);
 126       policy_schema->Set(schema::kItems, items.release());
 127     }
 128   }
 129
 130   std::string serialized;
 131   base::JSONWriter::Write(json.get(), &serialized);
 132   return serialized;
 133 }
 134
 135 // Verifies that untrusted policies contain only safe values. Modifies the
 136 // |policy| in place.
 137 void FilterUntrustedPolicy(PolicyMap* policy) {
 138   if (base::win::IsEnrolledToDomain())
 139     return;
 140
 141   int invalid_policies = 0;
 142   const PolicyMap::Entry* map_entry =
 143       policy->Get(key::kExtensionInstallForcelist);
 144   if (map_entry && map_entry->value) {
 145     const base::ListValue* policy_list_value = NULL;
 146     if (!map_entry->value->GetAsList(&policy_list_value))
 147       return;
 148
 149     scoped_ptr<base::ListValue> filtered_values(new base::ListValue);
 150     for (base::ListValue::const_iterator list_entry(policy_list_value->begin());
 151          list_entry != policy_list_value->end(); ++list_entry) {
 152       std::string entry;
 153       if (!(*list_entry)->GetAsString(&entry))
 154         continue;
 155       size_t pos = entry.find(';');
 156       if (pos == std::string::npos)
 157         continue;
 158       // Only allow custom update urls in enterprise environments.
 159       if (!LowerCaseEqualsASCII(entry.substr(pos), kExpectedWebStoreUrl)) {
 160         entry = kBlockedExtensionPrefix + entry;
 161         invalid_policies++;
 162       }
 163
 164       filtered_values->AppendString(entry);
 165     }
 166     if (invalid_policies) {
 167       policy->Set(key::kExtensionInstallForcelist,
 168                   map_entry->level, map_entry->scope,
 169                   filtered_values.release(),
 170                   map_entry->external_data_fetcher);
 171
 172       const PolicyDetails* details = GetChromePolicyDetails(
 173           key::kExtensionInstallForcelist);
 174       UMA_HISTOGRAM_SPARSE_SLOWLY("EnterpriseCheck.InvalidPolicies",
 175                                   details->id);
 176     }
 177   }
 178
 179   for (size_t i = 0; i < arraysize(kInsecurePolicies); ++i) {
 180     if (policy->Get(kInsecurePolicies[i])) {
 181       // TODO(pastarmovj): Surface this issue in the about:policy page.
 182       policy->Erase(kInsecurePolicies[i]);
 183       invalid_policies++;
 184       const PolicyDetails* details =
 185           GetChromePolicyDetails(kInsecurePolicies[i]);
 186       UMA_HISTOGRAM_SPARSE_SLOWLY("EnterpriseCheck.InvalidPolicies",
 187                                   details->id);
 188     }
 189   }
 190
 191   UMA_HISTOGRAM_COUNTS("EnterpriseCheck.InvalidPoliciesDetected",
 192                        invalid_policies);
 193 }
 194
 195 // A helper class encapsulating run-time-linked function calls to Wow64 APIs.
 196 class Wow64Functions {
 197  public:
 198   Wow64Functions()
 199     : kernel32_lib_(base::FilePath(L"kernel32")),
 200       is_wow_64_process_(NULL),
 201       wow_64_disable_wow_64_fs_redirection_(NULL),
 202       wow_64_revert_wow_64_fs_redirection_(NULL) {
 203     if (kernel32_lib_.is_valid()) {
 204       is_wow_64_process_ = reinterpret_cast<IsWow64Process>(
 205           kernel32_lib_.GetFunctionPointer("IsWow64Process"));
 206       wow_64_disable_wow_64_fs_redirection_ =
 207           reinterpret_cast<Wow64DisableWow64FSRedirection>(
 208               kernel32_lib_.GetFunctionPointer(
 209                   "Wow64DisableWow64FsRedirection"));
 210       wow_64_revert_wow_64_fs_redirection_ =
 211           reinterpret_cast<Wow64RevertWow64FSRedirection>(
 212               kernel32_lib_.GetFunctionPointer(
 213                   "Wow64RevertWow64FsRedirection"));
 214     }
 215   }
 216
 217   bool is_valid() {
 218     return is_wow_64_process_ &&
 219         wow_64_disable_wow_64_fs_redirection_ &&
 220         wow_64_revert_wow_64_fs_redirection_;
 221   }
 222
 223   bool IsWow64() {
 224     BOOL result = 0;
 225     if (!is_wow_64_process_(GetCurrentProcess(), &result))
 226       PLOG(WARNING) << "IsWow64ProcFailed";
 227     return !!result;
 228   }
 229
 230   bool DisableFsRedirection(PVOID* previous_state) {
 231     return !!wow_64_disable_wow_64_fs_redirection_(previous_state);
 232   }
 233
 234   bool RevertFsRedirection(PVOID previous_state) {
 235     return !!wow_64_revert_wow_64_fs_redirection_(previous_state);
 236   }
 237
 238  private:
 239   typedef BOOL (WINAPI* IsWow64Process)(HANDLE, PBOOL);
 240   typedef BOOL (WINAPI* Wow64DisableWow64FSRedirection)(PVOID*);
 241   typedef BOOL (WINAPI* Wow64RevertWow64FSRedirection)(PVOID);
 242
 243   base::ScopedNativeLibrary kernel32_lib_;
 244
 245   IsWow64Process is_wow_64_process_;
 246   Wow64DisableWow64FSRedirection wow_64_disable_wow_64_fs_redirection_;
 247   Wow64RevertWow64FSRedirection wow_64_revert_wow_64_fs_redirection_;
 248
 249   DISALLOW_COPY_AND_ASSIGN(Wow64Functions);
 250 };
 251
 252 // Global Wow64Function instance used by ScopedDisableWow64Redirection below.
 253 static base::LazyInstance<Wow64Functions> g_wow_64_functions =
 254     LAZY_INSTANCE_INITIALIZER;
 255
 256 // Scoper that switches off Wow64 File System Redirection during its lifetime.
 257 class ScopedDisableWow64Redirection {
 258  public:
 259   ScopedDisableWow64Redirection()
 260     : active_(false),
 261       previous_state_(NULL) {
 262     Wow64Functions* wow64 = g_wow_64_functions.Pointer();
 263     if (wow64->is_valid() && wow64->IsWow64()) {
 264       if (wow64->DisableFsRedirection(&previous_state_))
 265         active_ = true;
 266       else
 267         PLOG(WARNING) << "Wow64DisableWow64FSRedirection";
 268     }
 269   }
 270
 271   ~ScopedDisableWow64Redirection() {
 272     if (active_)
 273       CHECK(g_wow_64_functions.Get().RevertFsRedirection(previous_state_));
 274   }
 275
 276   bool is_active() { return active_; }
 277
 278  private:
 279   bool active_;
 280   PVOID previous_state_;
 281
 282   DISALLOW_COPY_AND_ASSIGN(ScopedDisableWow64Redirection);
 283 };
 284
 285 // AppliedGPOListProvider implementation that calls actual Windows APIs.
 286 class WinGPOListProvider : public AppliedGPOListProvider {
 287  public:
 288   virtual ~WinGPOListProvider() {}
 289
 290   // AppliedGPOListProvider:
 291   virtual DWORD GetAppliedGPOList(DWORD flags,
 292                                   LPCTSTR machine_name,
 293                                   PSID sid_user,
 294                                   GUID* extension_guid,
 295                                   PGROUP_POLICY_OBJECT* gpo_list) override {
 296     return ::GetAppliedGPOList(flags, machine_name, sid_user, extension_guid,
 297                                gpo_list);
 298   }
 299
 300   virtual BOOL FreeGPOList(PGROUP_POLICY_OBJECT gpo_list) override {
 301     return ::FreeGPOList(gpo_list);
 302   }
 303 };
 304
 305 // The default windows GPO list provider used for PolicyLoaderWin.
 306 static base::LazyInstance<WinGPOListProvider> g_win_gpo_list_provider =
 307     LAZY_INSTANCE_INITIALIZER;
 308
 309 // Parses |gpo_dict| according to |schema| and writes the resulting policy
 310 // settings to |policy| for the given |scope| and |level|.
 311 void ParsePolicy(const RegistryDict* gpo_dict,
 312                  PolicyLevel level,
 313                  PolicyScope scope,
 314                  const Schema& schema,
 315                  PolicyMap* policy) {
 316   if (!gpo_dict)
 317     return;
 318
 319   scoped_ptr<base::Value> policy_value(gpo_dict->ConvertToJSON(schema));
 320   const base::DictionaryValue* policy_dict = NULL;
 321   if (!policy_value->GetAsDictionary(&policy_dict) || !policy_dict) {
 322     LOG(WARNING) << "Root policy object is not a dictionary!";
 323     return;
 324   }
 325
 326   policy->LoadFrom(policy_dict, level, scope);
 327 }
 328
 329 // Collects stats about the enterprise environment that can be used to decide
 330 // how to parse the existing policy information.
 331 void CollectEnterpriseUMAs() {
 332   // Collect statistics about the windows suite.
 333   UMA_HISTOGRAM_ENUMERATION("EnterpriseCheck.OSType",
 334                             base::win::OSInfo::GetInstance()->version_type(),
 335                             base::win::SUITE_LAST);
 336
 337   // Get the computer's domain status.
 338   LPWSTR domain;
 339   NETSETUP_JOIN_STATUS join_status;
 340   if (NERR_Success != ::NetGetJoinInformation(NULL, &domain, &join_status)) {
 341     UMA_HISTOGRAM_ENUMERATION("EnterpriseCheck.DomainCheckFailed",
 342                               DOMAIN_CHECK_ERROR_GET_JOIN_INFO,
 343                               DOMAIN_CHECK_ERROR_SIZE);
 344     return;
 345   }
 346   ::NetApiBufferFree(domain);
 347
 348   bool in_domain = join_status == NetSetupDomainName;
 349   UMA_HISTOGRAM_BOOLEAN("EnterpriseCheck.InDomain", in_domain);
 350   if (in_domain) {
 351     // This check will tell us how often are domain computers actually
 352     // connected to the enterprise network while Chrome is running.
 353     HANDLE server_bind;
 354     if (ERROR_SUCCESS == ::DsBind(NULL, NULL, &server_bind)) {
 355       UMA_HISTOGRAM_COUNTS("EnterpriseCheck.DomainBindSucceeded", 1);
 356       ::DsUnBind(&server_bind);
 357     } else {
 358       UMA_HISTOGRAM_ENUMERATION("EnterpriseCheck.DomainCheckFailed",
 359                                 DOMAIN_CHECK_ERROR_DS_BIND,
 360                                 DOMAIN_CHECK_ERROR_SIZE);
 361     }
 362   }
 363 }
 364
 365 }  // namespace
 366
 367 const base::FilePath::CharType PolicyLoaderWin::kPRegFileName[] =
 368     FILE_PATH_LITERAL("Registry.pol");
 369
 370 PolicyLoaderWin::PolicyLoaderWin(
 371     scoped_refptr<base::SequencedTaskRunner> task_runner,
 372     const base::string16& chrome_policy_key,
 373     AppliedGPOListProvider* gpo_provider)
 374     : AsyncPolicyLoader(task_runner),
 375       is_initialized_(false),
 376       chrome_policy_key_(chrome_policy_key),
 377       gpo_provider_(gpo_provider),
 378       user_policy_changed_event_(false, false),
 379       machine_policy_changed_event_(false, false),
 380       user_policy_watcher_failed_(false),
 381       machine_policy_watcher_failed_(false) {
 382   if (!::RegisterGPNotification(user_policy_changed_event_.handle(), false)) {
 383     DPLOG(WARNING) << "Failed to register user group policy notification";
 384     user_policy_watcher_failed_ = true;
 385   }
 386   if (!::RegisterGPNotification(machine_policy_changed_event_.handle(), true)) {
 387     DPLOG(WARNING) << "Failed to register machine group policy notification.";
 388     machine_policy_watcher_failed_ = true;
 389   }
 390 }
 391
 392 PolicyLoaderWin::~PolicyLoaderWin() {
 393   if (!user_policy_watcher_failed_) {
 394     ::UnregisterGPNotification(user_policy_changed_event_.handle());
 395     user_policy_watcher_.StopWatching();
 396   }
 397   if (!machine_policy_watcher_failed_) {
 398     ::UnregisterGPNotification(machine_policy_changed_event_.handle());
 399     machine_policy_watcher_.StopWatching();
 400   }
 401 }
 402
 403 // static
 404 scoped_ptr<PolicyLoaderWin> PolicyLoaderWin::Create(
 405     scoped_refptr<base::SequencedTaskRunner> task_runner,
 406     const base::string16& chrome_policy_key) {
 407   return make_scoped_ptr(
 408       new PolicyLoaderWin(task_runner,
 409                           chrome_policy_key,
 410                           g_win_gpo_list_provider.Pointer()));
 411 }
 412
 413 void PolicyLoaderWin::InitOnBackgroundThread() {
 414   is_initialized_ = true;
 415   SetupWatches();
 416   CollectEnterpriseUMAs();
 417 }
 418
 419 scoped_ptr<PolicyBundle> PolicyLoaderWin::Load() {
 420   // Reset the watches BEFORE reading the individual policies to avoid
 421   // missing a change notification.
 422   if (is_initialized_)
 423     SetupWatches();
 424
 425   // Policy scope and corresponding hive.
 426   static const struct {
 427     PolicyScope scope;
 428     HKEY hive;
 429   } kScopes[] = {
 430     { POLICY_SCOPE_MACHINE, HKEY_LOCAL_MACHINE },
 431     { POLICY_SCOPE_USER,    HKEY_CURRENT_USER  },
 432   };
 433
 434   bool is_enterprise = base::win::IsEnrolledToDomain();
 435   VLOG(1) << "Reading policy from the registry is "
 436           << (is_enterprise ? "enabled." : "disabled.");
 437
 438   // Load policy data for the different scopes/levels and merge them.
 439   scoped_ptr<PolicyBundle> bundle(new PolicyBundle());
 440   PolicyMap* chrome_policy =
 441       &bundle->Get(PolicyNamespace(POLICY_DOMAIN_CHROME, std::string()));
 442   for (size_t i = 0; i < arraysize(kScopes); ++i) {
 443     PolicyScope scope = kScopes[i].scope;
 444     PolicyLoadStatusSample status;
 445     RegistryDict gpo_dict;
 446
 447     // Note: GPO rules mandate a call to EnterCriticalPolicySection() here, and
 448     // a matching LeaveCriticalPolicySection() call below after the
 449     // ReadPolicyFromGPO() block. Unfortunately, the policy mutex may be
 450     // unavailable for extended periods of time, and there are reports of this
 451     // happening in the wild: http://crbug.com/265862.
 452     //
 453     // Blocking for minutes is neither acceptable for Chrome startup, nor on
 454     // the FILE thread on which this code runs in steady state. Given that
 455     // there have never been any reports of issues due to partially-applied /
 456     // corrupt group policy, this code intentionally omits the
 457     // EnterCriticalPolicySection() call.
 458     //
 459     // If there's ever reason to revisit this decision, one option could be to
 460     // make the EnterCriticalPolicySection() call on a dedicated thread and
 461     // timeout on it more aggressively. For now, there's no justification for
 462     // the additional effort this would introduce.
 463
 464     bool is_registry_forced = is_enterprise || gpo_provider_ == nullptr;
 465     if (is_registry_forced || !ReadPolicyFromGPO(scope, &gpo_dict, &status)) {
 466       VLOG_IF(1, !is_registry_forced) << "Failed to read GPO files for "
 467                                       << scope << " falling back to registry.";
 468       gpo_dict.ReadRegistry(kScopes[i].hive, chrome_policy_key_);
 469     }
 470
 471     // Remove special-cased entries from the GPO dictionary.
 472     scoped_ptr<RegistryDict> recommended_dict(
 473         gpo_dict.RemoveKey(kKeyRecommended));
 474     scoped_ptr<RegistryDict> third_party_dict(
 475         gpo_dict.RemoveKey(kKeyThirdParty));
 476
 477     // Load Chrome policy.
 478     LoadChromePolicy(&gpo_dict, POLICY_LEVEL_MANDATORY, scope, chrome_policy);
 479     LoadChromePolicy(recommended_dict.get(), POLICY_LEVEL_RECOMMENDED, scope,
 480                      chrome_policy);
 481
 482     // Load 3rd-party policy.
 483     if (third_party_dict)
 484       Load3rdPartyPolicy(third_party_dict.get(), scope, bundle.get());
 485   }
 486
 487   return bundle.Pass();
 488 }
 489
 490 bool PolicyLoaderWin::ReadPRegFile(const base::FilePath& preg_file,
 491                                    RegistryDict* policy,
 492                                    PolicyLoadStatusSample* status) {
 493   // The following deals with the minor annoyance that Wow64 FS redirection
 494   // might need to be turned off: This is the case if running as a 32-bit
 495   // process on a 64-bit system, in which case Wow64 FS redirection redirects
 496   // access to the %WINDIR%/System32/GroupPolicy directory to
 497   // %WINDIR%/SysWOW64/GroupPolicy, but the file is actually in the
 498   // system-native directory.
 499   if (base::PathExists(preg_file)) {
 500     return preg_parser::ReadFile(preg_file, chrome_policy_key_, policy, status);
 501   } else {
 502     // Try with redirection switched off.
 503     ScopedDisableWow64Redirection redirection_disable;
 504     if (redirection_disable.is_active() && base::PathExists(preg_file)) {
 505       status->Add(POLICY_LOAD_STATUS_WOW64_REDIRECTION_DISABLED);
 506       return preg_parser::ReadFile(preg_file, chrome_policy_key_, policy,
 507                                    status);
 508     }
 509   }
 510
 511   // Report the error.
 512   LOG(ERROR) << "PReg file doesn't exist: " << preg_file.value();
 513   status->Add(POLICY_LOAD_STATUS_MISSING);
 514   return false;
 515 }
 516
 517 bool PolicyLoaderWin::LoadGPOPolicy(PolicyScope scope,
 518                                     PGROUP_POLICY_OBJECT policy_object_list,
 519                                     RegistryDict* policy,
 520                                     PolicyLoadStatusSample* status) {
 521   RegistryDict parsed_policy;
 522   RegistryDict forced_policy;
 523   for (GROUP_POLICY_OBJECT* policy_object = policy_object_list;
 524        policy_object; policy_object = policy_object->pNext) {
 525     if (policy_object->dwOptions & GPO_FLAG_DISABLE)
 526       continue;
 527
 528     if (PathIsUNC(policy_object->lpFileSysPath)) {
 529       // UNC path: Assume this is an AD-managed machine, which updates the
 530       // registry via GPO's standard registry CSE periodically. Fall back to
 531       // reading from the registry in this case.
 532       status->Add(POLICY_LOAD_STATUS_INACCCESSIBLE);
 533       return false;
 534     }
 535
 536     base::FilePath preg_file_path(
 537         base::FilePath(policy_object->lpFileSysPath).Append(kPRegFileName));
 538     if (policy_object->dwOptions & GPO_FLAG_FORCE) {
 539       RegistryDict new_forced_policy;
 540       if (!ReadPRegFile(preg_file_path, &new_forced_policy, status))
 541         return false;
 542
 543       // Merge with existing forced policy, giving precedence to the existing
 544       // forced policy.
 545       new_forced_policy.Merge(forced_policy);
 546       forced_policy.Swap(&new_forced_policy);
 547     } else {
 548       if (!ReadPRegFile(preg_file_path, &parsed_policy, status))
 549         return false;
 550     }
 551   }
 552
 553   // Merge, give precedence to forced policy.
 554   parsed_policy.Merge(forced_policy);
 555   policy->Swap(&parsed_policy);
 556
 557   return true;
 558 }
 559
 560 bool PolicyLoaderWin::ReadPolicyFromGPO(PolicyScope scope,
 561                                         RegistryDict* policy,
 562                                         PolicyLoadStatusSample* status) {
 563   PGROUP_POLICY_OBJECT policy_object_list = NULL;
 564   DWORD flags = scope == POLICY_SCOPE_MACHINE ? GPO_LIST_FLAG_MACHINE : 0;
 565   if (gpo_provider_->GetAppliedGPOList(
 566           flags, NULL, NULL, &kRegistrySettingsCSEGUID,
 567           &policy_object_list) != ERROR_SUCCESS) {
 568     PLOG(ERROR) << "GetAppliedGPOList scope " << scope;
 569     status->Add(POLICY_LOAD_STATUS_QUERY_FAILED);
 570     return false;
 571   }
 572
 573   bool result = true;
 574   if (policy_object_list) {
 575     result = LoadGPOPolicy(scope, policy_object_list, policy, status);
 576     if (!gpo_provider_->FreeGPOList(policy_object_list))
 577       LOG(WARNING) << "FreeGPOList";
 578   } else {
 579     status->Add(POLICY_LOAD_STATUS_NO_POLICY);
 580   }
 581
 582   return result;
 583 }
 584
 585 void PolicyLoaderWin::LoadChromePolicy(const RegistryDict* gpo_dict,
 586                                        PolicyLevel level,
 587                                        PolicyScope scope,
 588                                        PolicyMap* chrome_policy_map) {
 589   PolicyMap policy;
 590   const Schema* chrome_schema =
 591       schema_map()->GetSchema(PolicyNamespace(POLICY_DOMAIN_CHROME, ""));
 592   ParsePolicy(gpo_dict, level, scope, *chrome_schema, &policy);
 593   FilterUntrustedPolicy(&policy);
 594   chrome_policy_map->MergeFrom(policy);
 595 }
 596
 597 void PolicyLoaderWin::Load3rdPartyPolicy(const RegistryDict* gpo_dict,
 598                                          PolicyScope scope,
 599                                          PolicyBundle* bundle) {
 600   // Map of known 3rd party policy domain name to their enum values.
 601   static const struct {
 602     const char* name;
 603     PolicyDomain domain;
 604   } k3rdPartyDomains[] = {
 605     { "extensions", POLICY_DOMAIN_EXTENSIONS },
 606   };
 607
 608   // Policy level and corresponding path.
 609   static const struct {
 610     PolicyLevel level;
 611     const char* path;
 612   } kLevels[] = {
 613     { POLICY_LEVEL_MANDATORY,   kKeyMandatory   },
 614     { POLICY_LEVEL_RECOMMENDED, kKeyRecommended },
 615   };
 616
 617   for (size_t i = 0; i < arraysize(k3rdPartyDomains); i++) {
 618     const char* name = k3rdPartyDomains[i].name;
 619     const PolicyDomain domain = k3rdPartyDomains[i].domain;
 620     const RegistryDict* domain_dict = gpo_dict->GetKey(name);
 621     if (!domain_dict)
 622       continue;
 623
 624     for (RegistryDict::KeyMap::const_iterator component(
 625              domain_dict->keys().begin());
 626          component != domain_dict->keys().end();
 627          ++component) {
 628       const PolicyNamespace policy_namespace(domain, component->first);
 629
 630       const Schema* schema_from_map = schema_map()->GetSchema(policy_namespace);
 631       if (!schema_from_map) {
 632         // This extension isn't installed or doesn't support policies.
 633         continue;
 634       }
 635       Schema schema = *schema_from_map;
 636
 637       if (!schema.valid() &&
 638           policy_namespace.domain == POLICY_DOMAIN_EXTENSIONS &&
 639           policy_namespace.component_id == kLegacyBrowserSupportExtensionId) {
 640         // TODO(joaodasilva): remove this special treatment for LBS by M35.
 641         std::string schema_json;
 642         const base::Value* value = component->second->GetValue(kKeySchema);
 643         if (value && value->GetAsString(&schema_json)) {
 644           std::string error;
 645           schema = Schema::Parse(PatchSchema(schema_json), &error);
 646           if (!schema.valid())
 647             LOG(WARNING) << "Invalid schema in the registry for LBS: " << error;
 648         }
 649       }
 650
 651       // Parse policy.
 652       for (size_t j = 0; j < arraysize(kLevels); j++) {
 653         const RegistryDict* policy_dict =
 654             component->second->GetKey(kLevels[j].path);
 655         if (!policy_dict)
 656           continue;
 657
 658         PolicyMap policy;
 659         ParsePolicy(policy_dict, kLevels[j].level, scope, schema, &policy);
 660         bundle->Get(policy_namespace).MergeFrom(policy);
 661       }
 662     }
 663   }
 664 }
 665
 666 void PolicyLoaderWin::SetupWatches() {
 667   DCHECK(is_initialized_);
 668   if (!user_policy_watcher_failed_ &&
 669       !user_policy_watcher_.GetWatchedObject() &&
 670       !user_policy_watcher_.StartWatching(
 671           user_policy_changed_event_.handle(), this)) {
 672     DLOG(WARNING) << "Failed to start watch for user policy change event";
 673     user_policy_watcher_failed_ = true;
 674   }
 675   if (!machine_policy_watcher_failed_ &&
 676       !machine_policy_watcher_.GetWatchedObject() &&
 677       !machine_policy_watcher_.StartWatching(
 678           machine_policy_changed_event_.handle(), this)) {
 679     DLOG(WARNING) << "Failed to start watch for machine policy change event";
 680     machine_policy_watcher_failed_ = true;
 681   }
 682 }
 683
 684 void PolicyLoaderWin::OnObjectSignaled(HANDLE object) {
 685   DCHECK(object == user_policy_changed_event_.handle() ||
 686          object == machine_policy_changed_event_.handle())
 687       << "unexpected object signaled policy reload, obj = "
 688       << std::showbase << std::hex << object;
 689   Reload(false);
 690 }
 691
 692 }  // namespace policy