extensions/common/manifest.cc

   1 // Copyright 2013 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 "extensions/common/manifest.h"
   6
   7 #include "base/basictypes.h"
   8 #include "base/lazy_instance.h"
   9 #include "base/logging.h"
  10 #include "base/strings/string_split.h"
  11 #include "base/strings/stringprintf.h"
  12 #include "base/strings/utf_string_conversions.h"
  13 #include "extensions/common/error_utils.h"
  14 #include "extensions/common/features/feature.h"
  15 #include "extensions/common/features/feature_provider.h"
  16 #include "extensions/common/install_warning.h"
  17 #include "extensions/common/manifest_constants.h"
  18
  19 namespace extensions {
  20
  21 namespace keys = manifest_keys;
  22
  23 namespace {
  24
  25 // Rank extension locations in a way that allows
  26 // Manifest::GetHigherPriorityLocation() to compare locations.
  27 // An extension installed from two locations will have the location
  28 // with the higher rank, as returned by this function. The actual
  29 // integer values may change, and should never be persisted.
  30 int GetLocationRank(Manifest::Location location) {
  31   const int kInvalidRank = -1;
  32   int rank = kInvalidRank;  // Will CHECK that rank is not kInvalidRank.
  33
  34   switch (location) {
  35     // Component extensions can not be overriden by any other type.
  36     case Manifest::COMPONENT:
  37       rank = 9;
  38       break;
  39
  40     case Manifest::EXTERNAL_COMPONENT:
  41       rank = 8;
  42       break;
  43
  44     // Policy controlled extensions may not be overridden by any type
  45     // that is not part of chrome.
  46     case Manifest::EXTERNAL_POLICY:
  47       rank = 7;
  48       break;
  49
  50     case Manifest::EXTERNAL_POLICY_DOWNLOAD:
  51       rank = 6;
  52       break;
  53
  54     // A developer-loaded extension should override any installed type
  55     // that a user can disable. Anything specified on the command-line should
  56     // override one loaded via the extensions UI.
  57     case Manifest::COMMAND_LINE:
  58       rank = 5;
  59       break;
  60
  61     case Manifest::UNPACKED:
  62       rank = 4;
  63       break;
  64
  65     // The relative priority of various external sources is not important,
  66     // but having some order ensures deterministic behavior.
  67     case Manifest::EXTERNAL_REGISTRY:
  68       rank = 3;
  69       break;
  70
  71     case Manifest::EXTERNAL_PREF:
  72       rank = 2;
  73       break;
  74
  75     case Manifest::EXTERNAL_PREF_DOWNLOAD:
  76       rank = 1;
  77       break;
  78
  79     // User installed extensions are overridden by any external type.
  80     case Manifest::INTERNAL:
  81       rank = 0;
  82       break;
  83
  84     default:
  85       NOTREACHED() << "Need to add new extension location " << location;
  86   }
  87
  88   CHECK(rank != kInvalidRank);
  89   return rank;
  90 }
  91
  92 }  // namespace
  93
  94 // static
  95 Manifest::Location Manifest::GetHigherPriorityLocation(
  96     Location loc1, Location loc2) {
  97   if (loc1 == loc2)
  98     return loc1;
  99
 100   int loc1_rank = GetLocationRank(loc1);
 101   int loc2_rank = GetLocationRank(loc2);
 102
 103   // If two different locations have the same rank, then we can not
 104   // deterministicly choose a location.
 105   CHECK(loc1_rank != loc2_rank);
 106
 107   // Highest rank has highest priority.
 108   return (loc1_rank > loc2_rank ? loc1 : loc2 );
 109 }
 110
 111 Manifest::Manifest(Location location, scoped_ptr<base::DictionaryValue> value)
 112     : location_(location),
 113       value_(value.Pass()),
 114       type_(TYPE_UNKNOWN) {
 115   if (value_->HasKey(keys::kTheme)) {
 116     type_ = TYPE_THEME;
 117   } else if (value_->HasKey(keys::kExport)) {
 118     type_ = TYPE_SHARED_MODULE;
 119   } else if (value_->HasKey(keys::kApp)) {
 120     if (value_->Get(keys::kWebURLs, NULL) ||
 121         value_->Get(keys::kLaunchWebURL, NULL)) {
 122       type_ = TYPE_HOSTED_APP;
 123     } else if (value_->Get(keys::kPlatformAppBackground, NULL)) {
 124       type_ = TYPE_PLATFORM_APP;
 125     } else {
 126       type_ = TYPE_LEGACY_PACKAGED_APP;
 127     }
 128   } else {
 129     type_ = TYPE_EXTENSION;
 130   }
 131   CHECK_NE(type_, TYPE_UNKNOWN);
 132 }
 133
 134 Manifest::~Manifest() {
 135 }
 136
 137 bool Manifest::ValidateManifest(
 138     std::string* error,
 139     std::vector<InstallWarning>* warnings) const {
 140   *error = "";
 141
 142   // Check every feature to see if its in the manifest. Note that this means
 143   // we will ignore keys that are not features; we do this for forward
 144   // compatibility.
 145   // TODO(aa): Consider having an error here in the case of strict error
 146   // checking to let developers know when they screw up.
 147
 148   const FeatureProvider* manifest_feature_provider =
 149       FeatureProvider::GetManifestFeatures();
 150   const std::vector<std::string>& feature_names =
 151       manifest_feature_provider->GetAllFeatureNames();
 152   for (std::vector<std::string>::const_iterator feature_name =
 153            feature_names.begin();
 154        feature_name != feature_names.end(); ++feature_name) {
 155     // Use Get instead of HasKey because the former uses path expansion.
 156     if (!value_->Get(*feature_name, NULL))
 157       continue;
 158
 159     Feature* feature = manifest_feature_provider->GetFeature(*feature_name);
 160     Feature::Availability result = feature->IsAvailableToManifest(
 161         extension_id_, type_, location_, GetManifestVersion());
 162     if (!result.is_available())
 163       warnings->push_back(InstallWarning(result.message(), *feature_name));
 164   }
 165
 166   // Also generate warnings for keys that are not features.
 167   for (base::DictionaryValue::Iterator it(*value_); !it.IsAtEnd();
 168        it.Advance()) {
 169     if (!manifest_feature_provider->GetFeature(it.key())) {
 170       warnings->push_back(InstallWarning(
 171           ErrorUtils::FormatErrorMessage(
 172               manifest_errors::kUnrecognizedManifestKey, it.key()),
 173           it.key()));
 174     }
 175   }
 176   return true;
 177 }
 178
 179 bool Manifest::HasKey(const std::string& key) const {
 180   return CanAccessKey(key) && value_->HasKey(key);
 181 }
 182
 183 bool Manifest::HasPath(const std::string& path) const {
 184   base::Value* ignored = NULL;
 185   return CanAccessPath(path) && value_->Get(path, &ignored);
 186 }
 187
 188 bool Manifest::Get(
 189     const std::string& path, const base::Value** out_value) const {
 190   return CanAccessPath(path) && value_->Get(path, out_value);
 191 }
 192
 193 bool Manifest::GetBoolean(
 194     const std::string& path, bool* out_value) const {
 195   return CanAccessPath(path) && value_->GetBoolean(path, out_value);
 196 }
 197
 198 bool Manifest::GetInteger(
 199     const std::string& path, int* out_value) const {
 200   return CanAccessPath(path) && value_->GetInteger(path, out_value);
 201 }
 202
 203 bool Manifest::GetString(
 204     const std::string& path, std::string* out_value) const {
 205   return CanAccessPath(path) && value_->GetString(path, out_value);
 206 }
 207
 208 bool Manifest::GetString(
 209     const std::string& path, base::string16* out_value) const {
 210   return CanAccessPath(path) && value_->GetString(path, out_value);
 211 }
 212
 213 bool Manifest::GetDictionary(
 214     const std::string& path, const base::DictionaryValue** out_value) const {
 215   return CanAccessPath(path) && value_->GetDictionary(path, out_value);
 216 }
 217
 218 bool Manifest::GetList(
 219     const std::string& path, const base::ListValue** out_value) const {
 220   return CanAccessPath(path) && value_->GetList(path, out_value);
 221 }
 222
 223 Manifest* Manifest::DeepCopy() const {
 224   Manifest* manifest = new Manifest(
 225       location_, scoped_ptr<base::DictionaryValue>(value_->DeepCopy()));
 226   manifest->set_extension_id(extension_id_);
 227   return manifest;
 228 }
 229
 230 bool Manifest::Equals(const Manifest* other) const {
 231   return other && value_->Equals(other->value());
 232 }
 233
 234 int Manifest::GetManifestVersion() const {
 235   // Platform apps were launched after manifest version 2 was the preferred
 236   // version, so they default to that.
 237   int manifest_version = type_ == TYPE_PLATFORM_APP ? 2 : 1;
 238   value_->GetInteger(keys::kManifestVersion, &manifest_version);
 239   return manifest_version;
 240 }
 241
 242 bool Manifest::CanAccessPath(const std::string& path) const {
 243   std::string key;
 244   for (const base::StringPiece& component : base::SplitStringPiece(
 245            path, ".", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL)) {
 246     component.AppendToString(&key);
 247     if (!CanAccessKey(key))
 248       return false;
 249     key += '.';
 250   }
 251   return true;
 252 }
 253
 254 bool Manifest::CanAccessKey(const std::string& key) const {
 255   Feature* feature = FeatureProvider::GetManifestFeatures()->GetFeature(key);
 256   if (!feature)
 257     return true;
 258
 259   return feature->IsAvailableToManifest(
 260                       extension_id_, type_, location_, GetManifestVersion())
 261       .is_available();
 262 }
 263
 264 }  // namespace extensions