sandbox/win/src/handle_table.h

   1 // Copyright (c) 2011 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 SANDBOX_SRC_HANDLE_TABLE_H_
   6 #define SANDBOX_SRC_HANDLE_TABLE_H_
   7
   8 #include <windows.h>
   9 #include <vector>
  10
  11 #include "base/basictypes.h"
  12 #include "base/strings/string16.h"
  13 #include "sandbox/win/src/nt_internals.h"
  14
  15 namespace sandbox {
  16
  17 // HandleTable retrieves the global handle table and provides helper classes
  18 // for iterating through the table and retrieving handle info.
  19 class HandleTable {
  20  public:
  21   static const char16* HandleTable::kTypeProcess;
  22   static const char16* HandleTable::kTypeThread;
  23   static const char16* HandleTable::kTypeFile;
  24   static const char16* HandleTable::kTypeDirectory;
  25   static const char16* HandleTable::kTypeKey;
  26   static const char16* HandleTable::kTypeWindowStation;
  27   static const char16* HandleTable::kTypeDesktop;
  28   static const char16* HandleTable::kTypeService;
  29   static const char16* HandleTable::kTypeMutex;
  30   static const char16* HandleTable::kTypeSemaphore;
  31   static const char16* HandleTable::kTypeEvent;
  32   static const char16* HandleTable::kTypeTimer;
  33   static const char16* HandleTable::kTypeNamedPipe;
  34   static const char16* HandleTable::kTypeJobObject;
  35   static const char16* HandleTable::kTypeFileMap;
  36   static const char16* HandleTable::kTypeAlpcPort;
  37
  38   class Iterator;
  39
  40   // Used by the iterator to provide simple caching accessors to handle data.
  41   class HandleEntry {
  42    public:
  43     bool operator==(const HandleEntry& rhs) const {
  44       return handle_entry_ == rhs.handle_entry_;
  45     }
  46
  47     bool operator!=(const HandleEntry& rhs) const {
  48       return handle_entry_ != rhs.handle_entry_;
  49     }
  50
  51     const SYSTEM_HANDLE_INFORMATION* handle_entry() const {
  52       return handle_entry_;
  53     }
  54
  55     const OBJECT_TYPE_INFORMATION* TypeInfo();
  56
  57     const string16& Name();
  58
  59     const string16& Type();
  60
  61     bool IsType(const string16& type_string);
  62
  63    private:
  64     friend class Iterator;
  65     friend class HandleTable;
  66
  67     enum UpdateType {
  68       UPDATE_INFO_ONLY,
  69       UPDATE_INFO_AND_NAME,
  70       UPDATE_INFO_AND_TYPE_NAME,
  71     };
  72
  73     explicit HandleEntry(const SYSTEM_HANDLE_INFORMATION* handle_info_entry);
  74
  75     bool needs_info_update() { return handle_entry_ != last_entry_; }
  76
  77     void UpdateInfo(UpdateType flag);
  78
  79     OBJECT_TYPE_INFORMATION* type_info_internal() {
  80       return reinterpret_cast<OBJECT_TYPE_INFORMATION*>(
  81           &(type_info_buffer_[0]));
  82     }
  83
  84     const SYSTEM_HANDLE_INFORMATION* handle_entry_;
  85     const SYSTEM_HANDLE_INFORMATION* last_entry_;
  86     std::vector<BYTE> type_info_buffer_;
  87     string16 handle_name_;
  88     string16 type_name_;
  89
  90     DISALLOW_COPY_AND_ASSIGN(HandleEntry);
  91   };
  92
  93   class Iterator {
  94    public:
  95     Iterator(const HandleTable& table, const SYSTEM_HANDLE_INFORMATION* start,
  96              const SYSTEM_HANDLE_INFORMATION* stop);
  97
  98     Iterator(const Iterator& it);
  99
 100     Iterator& operator++() {
 101       if (++(current_.handle_entry_) == end_)
 102         current_.handle_entry_ = table_.end();
 103       return *this;
 104     }
 105
 106     bool operator==(const Iterator& rhs) const {
 107       return current_ == rhs.current_;
 108     }
 109
 110     bool operator!=(const Iterator& rhs) const {
 111       return current_ != rhs.current_;
 112     }
 113
 114     HandleEntry& operator*() { return current_; }
 115
 116     operator const SYSTEM_HANDLE_INFORMATION*() {
 117       return current_.handle_entry_;
 118     }
 119
 120     HandleEntry* operator->() { return &current_; }
 121
 122    private:
 123     const HandleTable& table_;
 124     HandleEntry current_;
 125     const SYSTEM_HANDLE_INFORMATION* end_;
 126   };
 127
 128   HandleTable();
 129
 130   Iterator begin() const {
 131     return Iterator(*this, handle_info()->Information,
 132         &handle_info()->Information[handle_info()->NumberOfHandles]);
 133   }
 134
 135   const SYSTEM_HANDLE_INFORMATION_EX* handle_info() const {
 136     return reinterpret_cast<const SYSTEM_HANDLE_INFORMATION_EX*>(
 137         &(handle_info_buffer_[0]));
 138   }
 139
 140   // Returns an iterator to the handles for only the supplied process ID.
 141   Iterator HandlesForProcess(ULONG process_id) const;
 142   const SYSTEM_HANDLE_INFORMATION* end() const {
 143     return &handle_info()->Information[handle_info()->NumberOfHandles];
 144   }
 145
 146  private:
 147   SYSTEM_HANDLE_INFORMATION_EX* handle_info_internal() {
 148     return reinterpret_cast<SYSTEM_HANDLE_INFORMATION_EX*>(
 149         &(handle_info_buffer_[0]));
 150   }
 151
 152   std::vector<BYTE> handle_info_buffer_;
 153
 154   DISALLOW_COPY_AND_ASSIGN(HandleTable);
 155 };
 156
 157 }  // namespace sandbox
 158
 159 #endif  // SANDBOX_SRC_HANDLE_TABLE_H_