sandbox/win/src/handle_table.cc

   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 #include "sandbox/win/src/handle_table.h"
   6
   7 #include <algorithm>
   8 #include <cstdlib>
   9
  10 #include "base/logging.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "sandbox/win/src/win_utils.h"
  13
  14 namespace {
  15
  16 bool CompareHandleEntries(const SYSTEM_HANDLE_INFORMATION& a,
  17                           const SYSTEM_HANDLE_INFORMATION& b) {
  18   return a.ProcessId < b.ProcessId;
  19 }
  20
  21 }  // namespace
  22
  23 namespace sandbox {
  24
  25 const char16* HandleTable::kTypeProcess = L"Process";
  26 const char16* HandleTable::kTypeThread = L"Thread";
  27 const char16* HandleTable::kTypeFile = L"File";
  28 const char16* HandleTable::kTypeDirectory = L"Directory";
  29 const char16* HandleTable::kTypeKey = L"Key";
  30 const char16* HandleTable::kTypeWindowStation = L"WindowStation";
  31 const char16* HandleTable::kTypeDesktop = L"Desktop";
  32 const char16* HandleTable::kTypeService = L"Service";
  33 const char16* HandleTable::kTypeMutex = L"Mutex";
  34 const char16* HandleTable::kTypeSemaphore = L"Semaphore";
  35 const char16* HandleTable::kTypeEvent = L"Event";
  36 const char16* HandleTable::kTypeTimer = L"Timer";
  37 const char16* HandleTable::kTypeNamedPipe = L"NamedPipe";
  38 const char16* HandleTable::kTypeJobObject = L"JobObject";
  39 const char16* HandleTable::kTypeFileMap = L"FileMap";
  40 const char16* HandleTable::kTypeAlpcPort = L"ALPC Port";
  41
  42 HandleTable::HandleTable() {
  43   static NtQuerySystemInformation QuerySystemInformation = NULL;
  44   if (!QuerySystemInformation)
  45     ResolveNTFunctionPtr("NtQuerySystemInformation", &QuerySystemInformation);
  46
  47   ULONG size = 0x15000;
  48   NTSTATUS result;
  49   do {
  50     handle_info_buffer_.resize(size);
  51     result = QuerySystemInformation(SystemHandleInformation,
  52         handle_info_internal(), size, &size);
  53   } while (result == STATUS_INFO_LENGTH_MISMATCH);
  54
  55   // We failed, so make an empty table.
  56   if (!NT_SUCCESS(result)) {
  57     handle_info_buffer_.resize(0);
  58     return;
  59   }
  60
  61   // Sort it to make process lookups faster.
  62   std::sort(handle_info_internal()->Information,
  63       handle_info_internal()->Information +
  64       handle_info_internal()->NumberOfHandles, CompareHandleEntries);
  65 }
  66
  67 HandleTable::Iterator HandleTable::HandlesForProcess(ULONG process_id) const {
  68   SYSTEM_HANDLE_INFORMATION key;
  69   key.ProcessId = process_id;
  70
  71   const SYSTEM_HANDLE_INFORMATION* start = handle_info()->Information;
  72   const SYSTEM_HANDLE_INFORMATION* finish =
  73       &handle_info()->Information[handle_info()->NumberOfHandles];
  74
  75   start = std::lower_bound(start, finish, key, CompareHandleEntries);
  76   if (start->ProcessId != process_id)
  77     return Iterator(*this, finish, finish);
  78   finish = std::upper_bound(start, finish, key, CompareHandleEntries);
  79   return Iterator(*this, start, finish);
  80 }
  81
  82 HandleTable::HandleEntry::HandleEntry(
  83     const SYSTEM_HANDLE_INFORMATION* handle_info_entry)
  84     : handle_entry_(handle_info_entry), last_entry_(0) {
  85 }
  86
  87 void HandleTable::HandleEntry::UpdateInfo(UpdateType flag) {
  88   static NtQueryObject QueryObject = NULL;
  89   if (!QueryObject)
  90     ResolveNTFunctionPtr("NtQueryObject", &QueryObject);
  91
  92   NTSTATUS result;
  93
  94   // Always update the basic type info, but grab the names as needed.
  95   if (needs_info_update()) {
  96     handle_name_.clear();
  97     type_name_.clear();
  98     last_entry_ = handle_entry_;
  99
 100     // Most handle names are very short, so start small and reuse this buffer.
 101     if (type_info_buffer_.empty())
 102       type_info_buffer_.resize(sizeof(OBJECT_TYPE_INFORMATION)
 103           + (32 * sizeof(wchar_t)));
 104     ULONG size = static_cast<ULONG>(type_info_buffer_.size());
 105     result = QueryObject(reinterpret_cast<HANDLE>(handle_entry_->Handle),
 106         ObjectTypeInformation, type_info_internal(), size, &size);
 107     while (result == STATUS_INFO_LENGTH_MISMATCH) {
 108       type_info_buffer_.resize(size);
 109       result = QueryObject(reinterpret_cast<HANDLE>(handle_entry_->Handle),
 110           ObjectTypeInformation, type_info_internal(), size, &size);
 111     }
 112
 113     if (!NT_SUCCESS(result)) {
 114       type_info_buffer_.clear();
 115       return;
 116     }
 117   }
 118
 119   // Don't bother copying out names until we ask for them, and then cache them.
 120   switch (flag) {
 121     case UPDATE_INFO_AND_NAME:
 122       if (type_info_buffer_.size() && handle_name_.empty()) {
 123         ULONG size = MAX_PATH;
 124         scoped_ptr<UNICODE_STRING, base::FreeDeleter> name;
 125         do {
 126           name.reset(static_cast<UNICODE_STRING*>(malloc(size)));
 127           DCHECK(name.get());
 128           result = QueryObject(reinterpret_cast<HANDLE>(
 129               handle_entry_->Handle), ObjectNameInformation, name.get(),
 130               size, &size);
 131         } while (result == STATUS_INFO_LENGTH_MISMATCH);
 132
 133         if (NT_SUCCESS(result)) {
 134           handle_name_.assign(name->Buffer, name->Length / sizeof(wchar_t));
 135         }
 136       }
 137       break;
 138
 139     case UPDATE_INFO_AND_TYPE_NAME:
 140       if (!type_info_buffer_.empty() && type_info_internal()->Name.Buffer &&
 141           type_name_.empty()) {
 142         type_name_.assign(type_info_internal()->Name.Buffer,
 143             type_info_internal()->Name.Length / sizeof(wchar_t));
 144       }
 145       break;
 146   }
 147 }
 148
 149 const OBJECT_TYPE_INFORMATION* HandleTable::HandleEntry::TypeInfo() {
 150   UpdateInfo(UPDATE_INFO_ONLY);
 151   return type_info_buffer_.empty() ? NULL : type_info_internal();
 152 }
 153
 154 const string16& HandleTable::HandleEntry::Name() {
 155   UpdateInfo(UPDATE_INFO_AND_NAME);
 156   return handle_name_;
 157 }
 158
 159 const string16& HandleTable::HandleEntry::Type() {
 160   UpdateInfo(UPDATE_INFO_AND_TYPE_NAME);
 161   return type_name_;
 162 }
 163
 164 bool HandleTable::HandleEntry::IsType(const string16& type_string) {
 165   UpdateInfo(UPDATE_INFO_ONLY);
 166   if (type_info_buffer_.empty())
 167     return false;
 168   return type_string.compare(0,
 169       type_info_internal()->Name.Length / sizeof(wchar_t),
 170       type_info_internal()->Name.Buffer) == 0;
 171 }
 172
 173 HandleTable::Iterator::Iterator(const HandleTable& table,
 174                                 const SYSTEM_HANDLE_INFORMATION* start,
 175                                 const SYSTEM_HANDLE_INFORMATION* end)
 176     : table_(table), current_(start), end_(end) {
 177 }
 178
 179 HandleTable::Iterator::Iterator(const Iterator& it)
 180     : table_(it.table_), current_(it.current_.handle_entry_), end_(it.end_) {
 181 }
 182
 183 }  // namespace sandbox