Cleanup/Remove Windows XP/Vista version checks from Windows sandbox code

sandbox/win/src/Wow64.cc

Index: sandbox/win/src/Wow64.cc
diff --git a/sandbox/win/src/Wow64.cc b/sandbox/win/src/Wow64.cc
deleted file mode 100644
index c5984d629ba1361e3484b6639f2cba1942d5dcd5..0000000000000000000000000000000000000000
--- a/sandbox/win/src/Wow64.cc
+++ /dev/null
@@ -1,226 +0,0 @@
-// Copyright (c) 2012 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/Wow64.h"
-
-#include <stddef.h>
-
-#include <sstream>
-
-#include "base/bit_cast.h"
-#include "base/logging.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/win/scoped_process_information.h"
-#include "base/win/windows_version.h"
-#include "sandbox/win/src/target_process.h"
-
-namespace {
-
-// Holds the information needed for the interception of NtMapViewOfSection on
-// 64 bits.
-// Warning: do not modify this definition without changing also the code on the
-// 64 bit helper process.
-struct PatchInfo32 {
-  HANDLE dll_load;  // Event to signal the broker.
-  ULONG pad1;
-  HANDLE continue_load;  // Event to wait for the broker.
-  ULONG pad2;
-  HANDLE section;  // First argument of the call.
-  ULONG pad3;
-  void* orig_MapViewOfSection;
-  ULONG original_high;
-  void* signal_and_wait;
-  ULONG pad4;
-  void* patch_location;
-  ULONG patch_high;
-};
-
-// Size of the 64 bit service entry.
-const SIZE_T kServiceEntry64Size = 0x10;
-
-// Removes the interception of ntdll64.
-bool Restore64Code(HANDLE child, PatchInfo32* patch_info) {
-  PatchInfo32 local_patch_info;
-  SIZE_T actual;
-  if (!::ReadProcessMemory(child, patch_info, &local_patch_info,
-                           sizeof(local_patch_info), &actual))
-    return false;
-  if (sizeof(local_patch_info) != actual)
-    return false;
-
-  if (local_patch_info.original_high)
-    return false;
-  if (local_patch_info.patch_high)
-    return false;
-
-  char buffer[kServiceEntry64Size];
-
-  if (!::ReadProcessMemory(child, local_patch_info.orig_MapViewOfSection,
-                           &buffer, kServiceEntry64Size, &actual))
-    return false;
-  if (kServiceEntry64Size != actual)
-    return false;
-
-  if (!::WriteProcessMemory(child, local_patch_info.patch_location, &buffer,
-                            kServiceEntry64Size, &actual))
-    return false;
-  if (kServiceEntry64Size != actual)
-    return false;
-  return true;
-}
-
-typedef BOOL (WINAPI* IsWow64ProcessFunction)(HANDLE process, BOOL* wow64);
-
-}  // namespace
-
-namespace sandbox {
-
-Wow64::Wow64(TargetProcess* child, HMODULE ntdll)
-    : child_(child), ntdll_(ntdll), dll_load_(NULL), continue_load_(NULL) {
-}
-
-Wow64::~Wow64() {
-}
-
-// The basic idea is to allocate one page of memory on the child, and initialize
-// the first part of it with our version of PatchInfo32. Then launch the helper
-// process passing it that address on the child. The helper process will patch
-// the 64 bit version of NtMapViewOfFile, and the interception will signal the
-// first event on the buffer. We'll be waiting on that event and after the 32
-// bit version of ntdll is loaded, we'll remove the interception and return to
-// our caller.
-bool Wow64::WaitForNtdll() {
-  if (base::win::OSInfo::GetInstance()->wow64_status() !=
-      base::win::OSInfo::WOW64_ENABLED)
-    return true;
-
-  const size_t page_size = 4096;
-
-  // Create some default manual reset un-named events, not signaled.
-  dll_load_.Set(::CreateEvent(NULL, TRUE, FALSE, NULL));
-  continue_load_.Set(::CreateEvent(NULL, TRUE, FALSE, NULL));
-  HANDLE current_process = ::GetCurrentProcess();
-  HANDLE remote_load, remote_continue;
-  DWORD access = EVENT_MODIFY_STATE | SYNCHRONIZE;
-  if (!::DuplicateHandle(current_process, dll_load_.Get(), child_->Process(),
-                         &remote_load, access, FALSE, 0)) {
-    return false;
-  }
-  if (!::DuplicateHandle(current_process, continue_load_.Get(),
-                         child_->Process(), &remote_continue, access, FALSE,
-                         0)) {
-    return false;
-  }
-
-  void* buffer = ::VirtualAllocEx(child_->Process(), NULL, page_size,
-                                  MEM_COMMIT, PAGE_EXECUTE_READWRITE);
-  DCHECK(buffer);
-  if (!buffer)
-    return false;
-
-  PatchInfo32* patch_info = reinterpret_cast<PatchInfo32*>(buffer);
-  PatchInfo32 local_patch_info = {0};
-  local_patch_info.dll_load = remote_load;
-  local_patch_info.continue_load = remote_continue;
-  SIZE_T written;
-  if (!::WriteProcessMemory(child_->Process(), patch_info, &local_patch_info,
-                            offsetof(PatchInfo32, section), &written))
-    return false;
-  if (offsetof(PatchInfo32, section) != written)
-    return false;
-
-  if (!RunWowHelper(buffer))
-    return false;
-
-  // The child is intercepted on 64 bit, go on and wait for our event.
-  if (!DllMapped())
-    return false;
-
-  // The 32 bit version is available, cleanup the child.
-  return Restore64Code(child_->Process(), patch_info);
-}
-
-bool Wow64::RunWowHelper(void* buffer) {
-  static_assert(sizeof(buffer) <= sizeof(DWORD), "unsupported 64 bits");
-
-  // Get the path to the helper (beside the exe).
-  wchar_t prog_name[MAX_PATH];
-  GetModuleFileNameW(NULL, prog_name, MAX_PATH);
-  base::string16 path(prog_name);
-  size_t name_pos = path.find_last_of(L"\\");
-  if (base::string16::npos == name_pos)
-    return false;
-  path.resize(name_pos + 1);
-
-  std::basic_stringstream<base::char16> command;
-  command << std::hex << std::showbase << L"\"" << path <<
-               L"wow_helper.exe\" " << child_->ProcessId() << " " <<
-               bit_cast<ULONG>(buffer);
-
-  scoped_ptr<wchar_t, base::FreeDeleter>
-      writable_command(_wcsdup(command.str().c_str()));
-
-  STARTUPINFO startup_info = {0};
-  startup_info.cb = sizeof(startup_info);
-  PROCESS_INFORMATION temp_process_info = {};
-  if (!::CreateProcess(NULL, writable_command.get(), NULL, NULL, FALSE, 0, NULL,
-                       NULL, &startup_info, &temp_process_info))
-    return false;
-  base::win::ScopedProcessInformation process_info(temp_process_info);
-
-  DWORD reason = ::WaitForSingleObject(process_info.process_handle(), INFINITE);
-
-  DWORD code;
-  bool ok =
-      ::GetExitCodeProcess(process_info.process_handle(), &code) ? true : false;
-
-  if (WAIT_TIMEOUT == reason)
-    return false;
-
-  return ok && (0 == code);
-}
-
-// First we must wake up the child, then wait for dll loads on the child until
-// the one we care is loaded; at that point we must suspend the child again.
-bool Wow64::DllMapped() {
-  if (1 != ::ResumeThread(child_->MainThread())) {
-    NOTREACHED();
-    return false;
-  }
-
-  for (;;) {
-    DWORD reason = ::WaitForSingleObject(dll_load_.Get(), INFINITE);
-    if (WAIT_TIMEOUT == reason || WAIT_ABANDONED == reason)
-      return false;
-
-    if (!::ResetEvent(dll_load_.Get()))
-      return false;
-
-    bool found = NtdllPresent();
-    if (found) {
-      if (::SuspendThread(child_->MainThread()))
-        return false;
-    }
-
-    if (!::SetEvent(continue_load_.Get()))
-      return false;
-
-    if (found)
-      return true;
-  }
-}
-
-bool Wow64::NtdllPresent() {
-  const size_t kBufferSize = 512;
-  char buffer[kBufferSize];
-  SIZE_T read;
-  if (!::ReadProcessMemory(child_->Process(), ntdll_, &buffer, kBufferSize,
-                           &read))
-    return false;
-  if (kBufferSize != read)
-    return false;
-  return true;
-}
-
-}  // namespace sandbox