The Tor Browser: security/sandbox/win/src/handle_closer.cc@6474c204b198 (annotated)

security/sandbox/win/src/handle_closer.cc@6474c204b198 (annotated)

security/sandbox/win/src/handle_closer.cc

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 #include "sandbox/win/src/handle_closer.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/win/windows_version.h"
 #include "sandbox/win/src/interceptors.h"
 #include "sandbox/win/src/internal_types.h"
 #include "sandbox/win/src/nt_internals.h"
 #include "sandbox/win/src/process_thread_interception.h"
 #include "sandbox/win/src/win_utils.h"
 namespace {
 template<typename T> T RoundUpToWordSize(T v) {
   if (size_t mod = v % sizeof(size_t))
     v += sizeof(size_t) - mod;
   return v;
 }
 template<typename T> T* RoundUpToWordSize(T* v) {
   return reinterpret_cast<T*>(RoundUpToWordSize(reinterpret_cast<size_t>(v)));
 }
 }  // namespace
 namespace sandbox {
 // Memory buffer mapped from the parent, with the list of handles.
 SANDBOX_INTERCEPT HandleCloserInfo* g_handles_to_close;
 HandleCloser::HandleCloser() {}
 ResultCode HandleCloser::AddHandle(const char16* handle_type,
                                    const char16* handle_name) {
   if (!handle_type)
     return SBOX_ERROR_BAD_PARAMS;
   HandleMap::iterator names = handles_to_close_.find(handle_type);
   if (names == handles_to_close_.end()) {  // We have no entries for this type.
     std::pair<HandleMap::iterator, bool> result = handles_to_close_.insert(
         HandleMap::value_type(handle_type, HandleMap::mapped_type()));
     names = result.first;
     if (handle_name)
       names->second.insert(handle_name);
   } else if (!handle_name) {  // Now we need to close all handles of this type.
     names->second.clear();
   } else if (!names->second.empty()) {  // Add another name for this type.
     names->second.insert(handle_name);
   }  // If we're already closing all handles of type then we're done.
   return SBOX_ALL_OK;
 }
 size_t HandleCloser::GetBufferSize() {
   size_t bytes_total = offsetof(HandleCloserInfo, handle_entries);
   for (HandleMap::iterator i = handles_to_close_.begin();
        i != handles_to_close_.end(); ++i) {
     size_t bytes_entry = offsetof(HandleListEntry, handle_type) +
         (i->first.size() + 1) * sizeof(char16);
     for (HandleMap::mapped_type::iterator j = i->second.begin();
          j != i->second.end(); ++j) {
       bytes_entry += ((*j).size() + 1) * sizeof(char16);
     }
     // Round up to the nearest multiple of word size.
     bytes_entry = RoundUpToWordSize(bytes_entry);
     bytes_total += bytes_entry;
   }
   return bytes_total;
 }
 bool HandleCloser::InitializeTargetHandles(TargetProcess* target) {
   // Do nothing on an empty list (global pointer already initialized to NULL).
   if (handles_to_close_.empty())
     return true;
   size_t bytes_needed = GetBufferSize();
   scoped_ptr<size_t[]> local_buffer(
       new size_t[bytes_needed / sizeof(size_t)]);
   if (!SetupHandleList(local_buffer.get(), bytes_needed))
     return false;
   HANDLE child = target->Process();
   // Allocate memory in the target process without specifying the address
   void* remote_data = ::VirtualAllocEx(child, NULL, bytes_needed,
                                        MEM_COMMIT, PAGE_READWRITE);
   if (NULL == remote_data)
     return false;
   // Copy the handle buffer over.
   SIZE_T bytes_written;
   BOOL result = ::WriteProcessMemory(child, remote_data, local_buffer.get(),
                                      bytes_needed, &bytes_written);
   if (!result || bytes_written != bytes_needed) {
     ::VirtualFreeEx(child, remote_data, 0, MEM_RELEASE);
     return false;
   }
   g_handles_to_close = reinterpret_cast<HandleCloserInfo*>(remote_data);
   ResultCode rc = target->TransferVariable("g_handles_to_close",
                                            &g_handles_to_close,
                                            sizeof(g_handles_to_close));
   return (SBOX_ALL_OK == rc);
 }
 bool HandleCloser::SetupHandleList(void* buffer, size_t buffer_bytes) {
   ::ZeroMemory(buffer, buffer_bytes);
   HandleCloserInfo* handle_info = reinterpret_cast<HandleCloserInfo*>(buffer);
   handle_info->record_bytes = buffer_bytes;
   handle_info->num_handle_types = handles_to_close_.size();
   char16* output = reinterpret_cast<char16*>(&handle_info->handle_entries[0]);
   char16* end = reinterpret_cast<char16*>(
       reinterpret_cast<char*>(buffer) + buffer_bytes);
   for (HandleMap::iterator i = handles_to_close_.begin();
        i != handles_to_close_.end(); ++i) {
     if (output >= end)
       return false;
     HandleListEntry* list_entry = reinterpret_cast<HandleListEntry*>(output);
     output = &list_entry->handle_type[0];
     // Copy the typename and set the offset and count.
     i->first._Copy_s(output, i->first.size(), i->first.size());
     *(output += i->first.size()) = L'\0';
     output++;
     list_entry->offset_to_names = reinterpret_cast<char*>(output) -
         reinterpret_cast<char*>(list_entry);
     list_entry->name_count = i->second.size();
     // Copy the handle names.
     for (HandleMap::mapped_type::iterator j = i->second.begin();
          j != i->second.end(); ++j) {
       output = std::copy((*j).begin(), (*j).end(), output) + 1;
     }
     // Round up to the nearest multiple of sizeof(size_t).
     output = RoundUpToWordSize(output);
     list_entry->record_bytes = reinterpret_cast<char*>(output) -
         reinterpret_cast<char*>(list_entry);
   }
   DCHECK_EQ(reinterpret_cast<size_t>(output), reinterpret_cast<size_t>(end));
   return output <= end;
 }
 bool HandleCloser::SetupHandleInterceptions(InterceptionManager* manager) {
   // We need to intercept CreateThread if we're closing ALPC port clients.
   HandleMap::iterator names = handles_to_close_.find(L"ALPC Port");
   if (base::win::GetVersion() >= base::win::VERSION_VISTA &&
       names != handles_to_close_.end() &&
       (names->second.empty() || names->second.size() == 0)) {
     if (!INTERCEPT_EAT(manager, kKerneldllName, CreateThread,
                        CREATE_THREAD_ID, 28)) {
       return false;
     }
     if (!INTERCEPT_EAT(manager, kKerneldllName, GetUserDefaultLCID,
                        GET_USER_DEFAULT_LCID_ID, 4)) {
       return false;
     }
     return true;
   }
   return true;
 }
 bool GetHandleName(HANDLE handle, string16* handle_name) {
   static NtQueryObject QueryObject = NULL;
   if (!QueryObject)
     ResolveNTFunctionPtr("NtQueryObject", &QueryObject);
   ULONG size = MAX_PATH;
   scoped_ptr<UNICODE_STRING, base::FreeDeleter> name;
   NTSTATUS result;
   do {
     name.reset(static_cast<UNICODE_STRING*>(malloc(size)));
     DCHECK(name.get());
     result = QueryObject(handle, ObjectNameInformation, name.get(),
                          size, &size);
   } while (result == STATUS_INFO_LENGTH_MISMATCH ||
            result == STATUS_BUFFER_OVERFLOW);
   if (NT_SUCCESS(result) && name->Buffer && name->Length)
     handle_name->assign(name->Buffer, name->Length / sizeof(wchar_t));
   else
     handle_name->clear();
   return NT_SUCCESS(result);
 }
 }  // namespace sandbox

The Tor Browser / annotate

security/sandbox/win/src/handle_closer.cc@6474c204b198 (annotated)

security/sandbox/win/src/handle_closer.cc