src/components/policy/core/common/config_dir_policy_loader.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 "components/policy/core/common/config_dir_policy_loader.h"
   6
   7 #include <algorithm>
   8 #include <set>
   9 #include <string>
  10
  11 #include "base/bind.h"
  12 #include "base/bind_helpers.h"
  13 #include "base/files/file_enumerator.h"
  14 #include "base/files/file_util.h"
  15 #include "base/json/json_file_value_serializer.h"
  16 #include "base/json/json_reader.h"
  17 #include "base/logging.h"
  18 #include "base/stl_util.h"
  19 #include "components/policy/core/common/policy_bundle.h"
  20 #include "components/policy/core/common/policy_load_status.h"
  21
  22 namespace policy {
  23
  24 namespace {
  25
  26 // Subdirectories that contain the mandatory and recommended policies.
  27 const base::FilePath::CharType kMandatoryConfigDir[] =
  28     FILE_PATH_LITERAL("managed");
  29 const base::FilePath::CharType kRecommendedConfigDir[] =
  30     FILE_PATH_LITERAL("recommended");
  31
  32 PolicyLoadStatus JsonErrorToPolicyLoadStatus(int status) {
  33   switch (status) {
  34     case JSONFileValueSerializer::JSON_ACCESS_DENIED:
  35     case JSONFileValueSerializer::JSON_CANNOT_READ_FILE:
  36     case JSONFileValueSerializer::JSON_FILE_LOCKED:
  37       return POLICY_LOAD_STATUS_READ_ERROR;
  38     case JSONFileValueSerializer::JSON_NO_SUCH_FILE:
  39       return POLICY_LOAD_STATUS_MISSING;
  40     case base::JSONReader::JSON_INVALID_ESCAPE:
  41     case base::JSONReader::JSON_SYNTAX_ERROR:
  42     case base::JSONReader::JSON_UNEXPECTED_TOKEN:
  43     case base::JSONReader::JSON_TRAILING_COMMA:
  44     case base::JSONReader::JSON_TOO_MUCH_NESTING:
  45     case base::JSONReader::JSON_UNEXPECTED_DATA_AFTER_ROOT:
  46     case base::JSONReader::JSON_UNSUPPORTED_ENCODING:
  47     case base::JSONReader::JSON_UNQUOTED_DICTIONARY_KEY:
  48       return POLICY_LOAD_STATUS_PARSE_ERROR;
  49     case base::JSONReader::JSON_NO_ERROR:
  50       NOTREACHED();
  51       return POLICY_LOAD_STATUS_STARTED;
  52   }
  53   NOTREACHED() << "Invalid status " << status;
  54   return POLICY_LOAD_STATUS_PARSE_ERROR;
  55 }
  56
  57 }  // namespace
  58
  59 ConfigDirPolicyLoader::ConfigDirPolicyLoader(
  60     scoped_refptr<base::SequencedTaskRunner> task_runner,
  61     const base::FilePath& config_dir,
  62     PolicyScope scope)
  63     : AsyncPolicyLoader(task_runner), config_dir_(config_dir), scope_(scope) {}
  64
  65 ConfigDirPolicyLoader::~ConfigDirPolicyLoader() {}
  66
  67 void ConfigDirPolicyLoader::InitOnBackgroundThread() {
  68   base::FilePathWatcher::Callback callback =
  69       base::Bind(&ConfigDirPolicyLoader::OnFileUpdated, base::Unretained(this));
  70   mandatory_watcher_.Watch(config_dir_.Append(kMandatoryConfigDir), false,
  71                            callback);
  72   recommended_watcher_.Watch(config_dir_.Append(kRecommendedConfigDir), false,
  73                              callback);
  74 }
  75
  76 scoped_ptr<PolicyBundle> ConfigDirPolicyLoader::Load() {
  77   scoped_ptr<PolicyBundle> bundle(new PolicyBundle());
  78   LoadFromPath(config_dir_.Append(kMandatoryConfigDir),
  79                POLICY_LEVEL_MANDATORY,
  80                bundle.get());
  81   LoadFromPath(config_dir_.Append(kRecommendedConfigDir),
  82                POLICY_LEVEL_RECOMMENDED,
  83                bundle.get());
  84   return bundle.Pass();
  85 }
  86
  87 base::Time ConfigDirPolicyLoader::LastModificationTime() {
  88   static const base::FilePath::CharType* kConfigDirSuffixes[] = {
  89     kMandatoryConfigDir,
  90     kRecommendedConfigDir,
  91   };
  92
  93   base::Time last_modification = base::Time();
  94   base::File::Info info;
  95
  96   for (size_t i = 0; i < arraysize(kConfigDirSuffixes); ++i) {
  97     base::FilePath path(config_dir_.Append(kConfigDirSuffixes[i]));
  98
  99     // Skip if the file doesn't exist, or it isn't a directory.
 100     if (!base::GetFileInfo(path, &info) || !info.is_directory)
 101       continue;
 102
 103     // Enumerate the files and find the most recent modification timestamp.
 104     base::FileEnumerator file_enumerator(path, false,
 105                                          base::FileEnumerator::FILES);
 106     for (base::FilePath config_file = file_enumerator.Next();
 107          !config_file.empty();
 108          config_file = file_enumerator.Next()) {
 109       if (base::GetFileInfo(config_file, &info) && !info.is_directory)
 110         last_modification = std::max(last_modification, info.last_modified);
 111     }
 112   }
 113
 114   return last_modification;
 115 }
 116
 117 void ConfigDirPolicyLoader::LoadFromPath(const base::FilePath& path,
 118                                          PolicyLevel level,
 119                                          PolicyBundle* bundle) {
 120   // Enumerate the files and sort them lexicographically.
 121   std::set<base::FilePath> files;
 122   base::FileEnumerator file_enumerator(path, false,
 123                                        base::FileEnumerator::FILES);
 124   for (base::FilePath config_file_path = file_enumerator.Next();
 125        !config_file_path.empty(); config_file_path = file_enumerator.Next())
 126     files.insert(config_file_path);
 127
 128   PolicyLoadStatusSample status;
 129   if (files.empty()) {
 130     status.Add(POLICY_LOAD_STATUS_NO_POLICY);
 131     return;
 132   }
 133
 134   // Start with an empty dictionary and merge the files' contents.
 135   // The files are processed in reverse order because |MergeFrom| gives priority
 136   // to existing keys, but the ConfigDirPolicyProvider gives priority to the
 137   // last file in lexicographic order.
 138   for (std::set<base::FilePath>::reverse_iterator config_file_iter =
 139            files.rbegin(); config_file_iter != files.rend();
 140        ++config_file_iter) {
 141     JSONFileValueSerializer deserializer(*config_file_iter);
 142     deserializer.set_allow_trailing_comma(true);
 143     int error_code = 0;
 144     std::string error_msg;
 145     scoped_ptr<base::Value> value(
 146         deserializer.Deserialize(&error_code, &error_msg));
 147     if (!value.get()) {
 148       LOG(WARNING) << "Failed to read configuration file "
 149                    << config_file_iter->value() << ": " << error_msg;
 150       status.Add(JsonErrorToPolicyLoadStatus(error_code));
 151       continue;
 152     }
 153     base::DictionaryValue* dictionary_value = NULL;
 154     if (!value->GetAsDictionary(&dictionary_value)) {
 155       LOG(WARNING) << "Expected JSON dictionary in configuration file "
 156                    << config_file_iter->value();
 157       status.Add(POLICY_LOAD_STATUS_PARSE_ERROR);
 158       continue;
 159     }
 160
 161     // Detach the "3rdparty" node.
 162     scoped_ptr<base::Value> third_party;
 163     if (dictionary_value->Remove("3rdparty", &third_party))
 164       Merge3rdPartyPolicy(third_party.get(), level, bundle);
 165
 166     // Add chrome policy.
 167     PolicyMap policy_map;
 168     policy_map.LoadFrom(dictionary_value, level, scope_);
 169     bundle->Get(PolicyNamespace(POLICY_DOMAIN_CHROME, std::string()))
 170         .MergeFrom(policy_map);
 171   }
 172 }
 173
 174 void ConfigDirPolicyLoader::Merge3rdPartyPolicy(
 175     const base::Value* policies,
 176     PolicyLevel level,
 177     PolicyBundle* bundle) {
 178   // The first-level entries in |policies| are PolicyDomains. The second-level
 179   // entries are component IDs, and the third-level entries are the policies
 180   // for that domain/component namespace.
 181
 182   const base::DictionaryValue* domains_dictionary;
 183   if (!policies->GetAsDictionary(&domains_dictionary)) {
 184     LOG(WARNING) << "3rdparty value is not a dictionary!";
 185     return;
 186   }
 187
 188   // Helper to lookup a domain given its string name.
 189   std::map<std::string, PolicyDomain> supported_domains;
 190   supported_domains["extensions"] = POLICY_DOMAIN_EXTENSIONS;
 191
 192   for (base::DictionaryValue::Iterator domains_it(*domains_dictionary);
 193        !domains_it.IsAtEnd(); domains_it.Advance()) {
 194     if (!ContainsKey(supported_domains, domains_it.key())) {
 195       LOG(WARNING) << "Unsupported 3rd party policy domain: "
 196                    << domains_it.key();
 197       continue;
 198     }
 199
 200     const base::DictionaryValue* components_dictionary;
 201     if (!domains_it.value().GetAsDictionary(&components_dictionary)) {
 202       LOG(WARNING) << "3rdparty/" << domains_it.key()
 203                    << " value is not a dictionary!";
 204       continue;
 205     }
 206
 207     PolicyDomain domain = supported_domains[domains_it.key()];
 208     for (base::DictionaryValue::Iterator components_it(*components_dictionary);
 209          !components_it.IsAtEnd(); components_it.Advance()) {
 210       const base::DictionaryValue* policy_dictionary;
 211       if (!components_it.value().GetAsDictionary(&policy_dictionary)) {
 212         LOG(WARNING) << "3rdparty/" << domains_it.key() << "/"
 213                      << components_it.key() << " value is not a dictionary!";
 214         continue;
 215       }
 216
 217       PolicyMap policy;
 218       policy.LoadFrom(policy_dictionary, level, scope_);
 219       bundle->Get(PolicyNamespace(domain, components_it.key()))
 220           .MergeFrom(policy);
 221     }
 222   }
 223 }
 224
 225 void ConfigDirPolicyLoader::OnFileUpdated(const base::FilePath& path,
 226                                           bool error) {
 227   if (!error)
 228     Reload(false);
 229 }
 230
 231 }  // namespace policy