extensions/common/permissions/set_disjunction_permission.h

   1 // Copyright 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 #ifndef EXTENSIONS_COMMON_PERMISSIONS_SET_DISJUNCTION_PERMISSION_H_
   6 #define EXTENSIONS_COMMON_PERMISSIONS_SET_DISJUNCTION_PERMISSION_H_
   7
   8 #include <set>
   9 #include <string>
  10
  11 #include "base/json/json_writer.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/values.h"
  14 #include "extensions/common/extension_messages.h"
  15 #include "extensions/common/permissions/api_permission.h"
  16 #include "ipc/ipc_message.h"
  17 #include "ipc/ipc_message_utils.h"
  18
  19 namespace extensions {
  20
  21 // An abstract base class for permissions that are represented by the
  22 // disjunction of a set of conditions.  Each condition is represented by a
  23 // |PermissionDataType| (e.g. SocketPermissionData).  If an
  24 // APIPermission::CheckParam matches any of the conditions in the set, the
  25 // permission is granted.
  26 //
  27 // For an example of how to use this class, see SocketPermission.
  28 template <class PermissionDataType, class DerivedType>
  29 class SetDisjunctionPermission : public APIPermission {
  30  public:
  31   explicit SetDisjunctionPermission(const APIPermissionInfo* info)
  32       : APIPermission(info) {}
  33
  34   ~SetDisjunctionPermission() override {}
  35
  36   // APIPermission overrides
  37   bool Check(const APIPermission::CheckParam* param) const override {
  38     for (typename std::set<PermissionDataType>::const_iterator i =
  39              data_set_.begin();
  40          i != data_set_.end();
  41          ++i) {
  42       if (i->Check(param))
  43         return true;
  44     }
  45     return false;
  46   }
  47
  48   bool Contains(const APIPermission* rhs) const override {
  49     CHECK(rhs->info() == info());
  50     const SetDisjunctionPermission* perm =
  51         static_cast<const SetDisjunctionPermission*>(rhs);
  52     return base::STLIncludes<std::set<PermissionDataType> >(
  53         data_set_, perm->data_set_);
  54   }
  55
  56   bool Equal(const APIPermission* rhs) const override {
  57     CHECK(rhs->info() == info());
  58     const SetDisjunctionPermission* perm =
  59         static_cast<const SetDisjunctionPermission*>(rhs);
  60     return data_set_ == perm->data_set_;
  61   }
  62
  63   APIPermission* Clone() const override {
  64     SetDisjunctionPermission* result = new DerivedType(info());
  65     result->data_set_ = data_set_;
  66     return result;
  67   }
  68
  69   APIPermission* Diff(const APIPermission* rhs) const override {
  70     CHECK(rhs->info() == info());
  71     const SetDisjunctionPermission* perm =
  72         static_cast<const SetDisjunctionPermission*>(rhs);
  73     scoped_ptr<SetDisjunctionPermission> result(new DerivedType(info()));
  74     result->data_set_ = base::STLSetDifference<std::set<PermissionDataType> >(
  75         data_set_, perm->data_set_);
  76     return result->data_set_.empty() ? NULL : result.release();
  77   }
  78
  79   APIPermission* Union(const APIPermission* rhs) const override {
  80     CHECK(rhs->info() == info());
  81     const SetDisjunctionPermission* perm =
  82         static_cast<const SetDisjunctionPermission*>(rhs);
  83     scoped_ptr<SetDisjunctionPermission> result(new DerivedType(info()));
  84     result->data_set_ = base::STLSetUnion<std::set<PermissionDataType> >(
  85         data_set_, perm->data_set_);
  86     return result.release();
  87   }
  88
  89   APIPermission* Intersect(const APIPermission* rhs) const override {
  90     CHECK(rhs->info() == info());
  91     const SetDisjunctionPermission* perm =
  92         static_cast<const SetDisjunctionPermission*>(rhs);
  93     scoped_ptr<SetDisjunctionPermission> result(new DerivedType(info()));
  94     result->data_set_ = base::STLSetIntersection<std::set<PermissionDataType> >(
  95         data_set_, perm->data_set_);
  96     return result->data_set_.empty() ? NULL : result.release();
  97   }
  98
  99   bool FromValue(
 100       const base::Value* value,
 101       std::string* error,
 102       std::vector<std::string>* unhandled_permissions) override {
 103     data_set_.clear();
 104     const base::ListValue* list = NULL;
 105
 106     if (!value || !value->GetAsList(&list) || list->GetSize() == 0) {
 107       if (error)
 108         *error = "NULL or empty permission list";
 109       return false;
 110     }
 111
 112     for (size_t i = 0; i < list->GetSize(); ++i) {
 113       const base::Value* item_value = NULL;
 114       bool got_item = list->Get(i, &item_value);
 115       DCHECK(got_item);
 116       DCHECK(item_value);
 117
 118       PermissionDataType data;
 119       if (data.FromValue(item_value)) {
 120         data_set_.insert(data);
 121       } else {
 122         std::string unknown_permission;
 123         base::JSONWriter::Write(*item_value, &unknown_permission);
 124         if (unhandled_permissions) {
 125           unhandled_permissions->push_back(unknown_permission);
 126         } else {
 127           if (error) {
 128             *error = "Cannot parse an item from the permission list: " +
 129                      unknown_permission;
 130           }
 131           return false;
 132         }
 133       }
 134     }
 135     return true;
 136   }
 137
 138   scoped_ptr<base::Value> ToValue() const override {
 139     base::ListValue* list = new base::ListValue();
 140     typename std::set<PermissionDataType>::const_iterator i;
 141     for (i = data_set_.begin(); i != data_set_.end(); ++i) {
 142       scoped_ptr<base::Value> item_value(i->ToValue());
 143       list->Append(item_value.release());
 144     }
 145     return scoped_ptr<base::Value>(list);
 146   }
 147
 148   void Write(IPC::Message* m) const override {
 149     IPC::WriteParam(m, data_set_);
 150   }
 151
 152   bool Read(const IPC::Message* m, base::PickleIterator* iter) override {
 153     return IPC::ReadParam(m, iter, &data_set_);
 154   }
 155
 156   void Log(std::string* log) const override {
 157     IPC::LogParam(data_set_, log);
 158   }
 159
 160  protected:
 161   std::set<PermissionDataType> data_set_;
 162 };
 163
 164 }  // namespace extensions
 165
 166 #endif  // EXTENSIONS_COMMON_PERMISSIONS_SET_DISJUNCTION_PERMISSION_H_