Integrate the Windows 8 code into the Chromium tree.

win8/delegate_execute/chrome_util.cc

+// 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 "win8/delegate_execute/chrome_util.h"
+
+#include <atlbase.h>
+#include <shlobj.h>
+#include <windows.h>
+
+#include <algorithm>
+#include <limits>
+#include <string>
+
+#include "base/file_path.h"
+#include "base/file_util.h"
+#include "base/md5.h"
+#include "base/process_util.h"
+#include "base/string_util.h"
+#include "base/utf_string_conversions.h"
+#include "base/win/registry.h"
+#include "base/win/scoped_comptr.h"
+#include "base/win/scoped_handle.h"
+#include "base/win/win_util.h"
+#include "google_update/google_update_idl.h"
+
+namespace {
+
+#if defined(GOOGLE_CHROME_BUILD)
+const wchar_t kAppUserModelId[] = L"Chrome";
+#else  // GOOGLE_CHROME_BUILD
+const wchar_t kAppUserModelId[] = L"Chromium";
+#endif  // GOOGLE_CHROME_BUILD
+
+#if defined(GOOGLE_CHROME_BUILD)
+
+// TODO(grt): These constants live in installer_util.  Consider moving them
+// into common_constants to allow for reuse.
+const FilePath::CharType kNewChromeExe[] = FILE_PATH_LITERAL("new_chrome.exe");
+const wchar_t kRenameCommandValue[] = L"cmd";
+const wchar_t kChromeAppGuid[] = L"{8A69D345-D564-463c-AFF1-A69D9E530F96}";
+const wchar_t kRegPathChromeClient[] =
+    L"Software\\Google\\Update\\Clients\\"
+    L"{8A69D345-D564-463c-AFF1-A69D9E530F96}";
+const int kExitCodeRenameSuccessful = 23;
+
+// Returns the name of the global event used to detect if |chrome_exe| is in
+// use by a browser process.
+// TODO(grt): Move this somewhere central so it can be used by both this
+// IsBrowserRunning (below) and IsBrowserAlreadyRunning (browser_util_win.cc).
+string16 GetEventName(const FilePath& chrome_exe) {
+  static wchar_t const kEventPrefix[] = L"Global\\";
+  const size_t prefix_len = arraysize(kEventPrefix) - 1;
+  string16 name;
+  name.reserve(prefix_len + chrome_exe.value().size());
+  name.assign(kEventPrefix, prefix_len);
+  name.append(chrome_exe.value());
+  std::replace(name.begin() + prefix_len, name.end(), '\\', '!');
+  std::transform(name.begin() + prefix_len, name.end(),
+                 name.begin() + prefix_len, tolower);
+  return name;
+}
+
+// Returns true if |chrome_exe| is in use by a browser process. In this case,
+// "in use" means past ChromeBrowserMainParts::PreMainMessageLoopRunImpl.
+bool IsBrowserRunning(const FilePath& chrome_exe) {
+  base::win::ScopedHandle handle(::OpenEvent(
+      SYNCHRONIZE, FALSE, GetEventName(chrome_exe).c_str()));
+  if (handle.IsValid())
+    return true;
+  DWORD last_error = ::GetLastError();
+  if (last_error != ERROR_FILE_NOT_FOUND) {
+    AtlTrace("%hs. Failed to open browser event; error %u.\n", __FUNCTION__,
+             last_error);
+  }
+  return false;
+}
+
+// Returns true if the file new_chrome.exe exists in the same directory as
+// |chrome_exe|.
+bool NewChromeExeExists(const FilePath& chrome_exe) {
+  FilePath new_chrome_exe(chrome_exe.DirName().Append(kNewChromeExe));
+  return file_util::PathExists(new_chrome_exe);
+}
+
+bool GetUpdateCommand(bool is_per_user, string16* update_command) {
+  const HKEY root = is_per_user ? HKEY_CURRENT_USER : HKEY_LOCAL_MACHINE;
+  base::win::RegKey key(root, kRegPathChromeClient, KEY_QUERY_VALUE);
+
+  return key.ReadValue(kRenameCommandValue, update_command) == ERROR_SUCCESS;
+}
+
+#endif  // GOOGLE_CHROME_BUILD
+
+// TODO(grt): This code also lives in installer_util.  Refactor for reuse.
+bool IsPerUserInstall(const FilePath& chrome_exe) {
+  wchar_t program_files_path[MAX_PATH] = {0};
+  if (SUCCEEDED(SHGetFolderPath(NULL, CSIDL_PROGRAM_FILES, NULL,
+                                SHGFP_TYPE_CURRENT, program_files_path))) {
+    return !StartsWith(chrome_exe.value().c_str(), program_files_path, false);
+  } else {
+    NOTREACHED();
+  }
+  return true;
+}
+
+// TODO(gab): This code also lives in shell_util. Refactor for reuse.
+string16 ByteArrayToBase32(const uint8* bytes, size_t size) {
+  static const char kEncoding[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567";
+
+  // Eliminate special cases first.
+  if (size == 0) {
+    return string16();
+  } else if (size == 1) {
+    string16 ret;
+    ret.push_back(kEncoding[(bytes[0] & 0xf8) >> 3]);
+    ret.push_back(kEncoding[(bytes[0] & 0x07) << 2]);
+    return ret;
+  } else if (size >= std::numeric_limits<size_t>::max() / 8) {
+    // If |size| is too big, the calculation of |encoded_length| below will
+    // overflow.
+    AtlTrace("%hs. Byte array is too long.\n", __FUNCTION__);
+    return string16();
+  }
+
+  // Overestimate the number of bits in the string by 4 so that dividing by 5
+  // is the equivalent of rounding up the actual number of bits divided by 5.
+  const size_t encoded_length = (size * 8 + 4) / 5;
+
+  string16 ret;
+  ret.reserve(encoded_length);
+
+  // A bit stream which will be read from the left and appended to from the
+  // right as it's emptied.
+  uint16 bit_stream = (bytes[0] << 8) + bytes[1];
+  size_t next_byte_index = 2;
+  int free_bits = 0;
+  while (free_bits < 16) {
+    // Extract the 5 leftmost bits in the stream
+    ret.push_back(kEncoding[(bit_stream & 0xf800) >> 11]);
+    bit_stream <<= 5;
+    free_bits += 5;
+
+    // If there is enough room in the bit stream, inject another byte (if there
+    // are any left...).
+    if (free_bits >= 8 && next_byte_index < size) {
+      free_bits -= 8;
+      bit_stream += bytes[next_byte_index++] << free_bits;
+    }
+  }
+
+  if (ret.length() != encoded_length) {
+    AtlTrace("%hs. Encoding doesn't match expected length.\n", __FUNCTION__);
+    return string16();
+  }
+  return ret;
+}
+
+// TODO(gab): This code also lives in shell_util. Refactor for reuse.
+bool GetUserSpecificRegistrySuffix(string16* suffix) {
+  string16 user_sid;
+  if (!base::win::GetUserSidString(&user_sid)) {
+    AtlTrace("%hs. GetUserSidString failed.\n", __FUNCTION__);
+    return false;
+  }
+  COMPILE_ASSERT(sizeof(base::MD5Digest) == 16, size_of_MD5_not_as_expected_);
+  base::MD5Digest md5_digest;
+  std::string user_sid_ascii(UTF16ToASCII(user_sid));
+  base::MD5Sum(user_sid_ascii.c_str(), user_sid_ascii.length(), &md5_digest);
+  const string16 base32_md5(
+      ByteArrayToBase32(md5_digest.a, arraysize(md5_digest.a)));
+  // The value returned by the base32 algorithm above must never change and must
+  // always be 26 characters long (i.e. if someone ever moves this to base and
+  // implements the full base32 algorithm (i.e. with appended '=' signs in the
+  // output), they must provide a flag to allow this method to still request
+  // the output with no appended '=' signs).
+  if (base32_md5.length() != 26U) {
+    AtlTrace("%hs. Base32 encoding of md5 hash is incorrect.\n", __FUNCTION__);
+    return false;
+  }
+  suffix->reserve(base32_md5.length() + 1);
+  suffix->assign(1, L'.');
+  suffix->append(base32_md5);
+  return true;
+}
+
+}  // namespace
+
+namespace delegate_execute {
+
+void UpdateChromeIfNeeded(const FilePath& chrome_exe) {
+#if defined(GOOGLE_CHROME_BUILD)
+  // Nothing to do if a browser is already running or if there's no
+  // new_chrome.exe.
+  if (IsBrowserRunning(chrome_exe) || !NewChromeExeExists(chrome_exe))
+    return;
+
+  base::ProcessHandle process_handle = base::kNullProcessHandle;
+
+  if (IsPerUserInstall(chrome_exe)) {
+    // Read the update command from the registry.
+    string16 update_command;
+    if (!GetUpdateCommand(true, &update_command)) {
+      AtlTrace("%hs. Failed to read update command from registry.\n",
+               __FUNCTION__);
+    } else {
+      // Run the update command.
+      base::LaunchOptions launch_options;
+      launch_options.start_hidden = true;
+      if (!base::LaunchProcess(update_command, launch_options,
+                               &process_handle)) {
+        AtlTrace("%hs. Failed to launch command to finalize update; "
+                 "error %u.\n", __FUNCTION__, ::GetLastError());
+        process_handle = base::kNullProcessHandle;
+      }
+    }
+  } else {
+    // Run the update command via Google Update.
+    HRESULT hr = S_OK;
+    base::win::ScopedComPtr<IProcessLauncher> process_launcher;
+    hr = process_launcher.CreateInstance(__uuidof(ProcessLauncherClass));
+    if (FAILED(hr)) {
+      AtlTrace("%hs. Failed to Create ProcessLauncher; hr=0x%X.\n",
+               __FUNCTION__, hr);
+    } else {
+      ULONG_PTR handle = 0;
+      hr = process_launcher->LaunchCmdElevated(
+          kChromeAppGuid, kRenameCommandValue, GetCurrentProcessId(), &handle);
+      if (FAILED(hr)) {
+        AtlTrace("%hs. Failed to launch command to finalize update; "
+                 "hr=0x%X.\n", __FUNCTION__, hr);
+      } else {
+        process_handle = reinterpret_cast<base::ProcessHandle>(handle);
+      }
+    }
+  }
+
+  // Wait for the update to complete and report the results.
+  if (process_handle != base::kNullProcessHandle) {
+    int exit_code = 0;
+    // WaitForExitCode will close the handle in all cases.
+    if (!base::WaitForExitCode(process_handle, &exit_code)) {
+      AtlTrace("%hs. Failed to get result when finalizing update.\n",
+               __FUNCTION__);
+    } else if (exit_code != kExitCodeRenameSuccessful) {
+      AtlTrace("%hs. Failed to finalize update with exit code %d.\n",
+               __FUNCTION__, exit_code);
+    } else {
+      AtlTrace("%hs. Finalized pending update.\n", __FUNCTION__);
+    }
+  }
+#endif
+}
+
+// TODO(gab): This code also lives in shell_util. Refactor for reuse.
+string16 GetAppId(const FilePath& chrome_exe) {
+  string16 app_id(kAppUserModelId);
+  string16 suffix;
+  if (IsPerUserInstall(chrome_exe) &&
+      !GetUserSpecificRegistrySuffix(&suffix)) {
+    AtlTrace("%hs. GetUserSpecificRegistrySuffix failed.\n",
+              __FUNCTION__);
+  }
+  return app_id.append(suffix);
+}
+
+}  // delegate_execute