// 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.

// The file contains the implementation of the mini_installer re-versioner.
// The main function (GenerateNextVersion) does the following in a temp dir:
// - Extracts and unpacks setup.exe and the Chrome-bin folder from
//   mini_installer.exe.
// - Inspects setup.exe to determine the current version.
// - Runs through all .dll and .exe files:
//   - Replacing all occurrences of the Unicode version string in the files'
//     resources with the updated string.
//   - For all resources in which the string substitution is made, the binary
//     form of the version is also replaced.
// - Re-packs setup.exe and Chrome-bin.
// - Inserts them into the target mini_installer.exe.
//
// This code assumes that the host program 1) initializes the process-wide
// CommandLine instance, and 2) resides in the output directory of a build
// tree.  When #2 is not the case, the --7za_path command-line switch may be
// used to provide the (relative or absolute) path to the directory containing
// 7za.exe.

#include "chrome/installer/test/alternate_version_generator.h"

#include <windows.h>

#include <algorithm>
#include <sstream>
#include <limits>
#include <utility>
#include <vector>

#include "base/basictypes.h"
#include "base/command_line.h"
#include "base/file_path.h"
#include "base/file_util.h"
#include "base/logging.h"
#include "base/path_service.h"
#include "base/platform_file.h"
#include "base/process_util.h"
#include "base/win/pe_image.h"
#include "base/win/scoped_handle.h"
#include "chrome/installer/test/pe_image_resources.h"
#include "chrome/installer/test/resource_loader.h"
#include "chrome/installer/test/resource_updater.h"
#include "chrome/installer/util/lzma_util.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace {

const wchar_t k7zaExe[] = L"7za.exe";
const wchar_t k7zaPathRelative[] = L"..\\..\\third_party\\lzma_sdk\\Executable";
const wchar_t kB7[] = L"B7";
const wchar_t kBl[] = L"BL";
const wchar_t kChrome7z[] = L"chrome.7z";
const wchar_t kChromeBin[] = L"Chrome-bin";
const wchar_t kChromePacked7z[] = L"chrome.packed.7z";
const wchar_t kExe[] = L"exe";
const wchar_t kExpandExe[] = L"expand.exe";
const wchar_t kExtDll[] = L".dll";
const wchar_t kExtExe[] = L".exe";
const wchar_t kMakeCab[] = L"makecab.exe";
const wchar_t kSetupEx_[] = L"setup.ex_";
const wchar_t kSetupExe[] = L"setup.exe";
const char kSwitch7zaPath[] = "7za_path";
const wchar_t kTempDirPrefix[] = L"mini_installer_test_temp";

// A helper class for creating and cleaning a temporary directory.  A temporary
// directory is created in Initialize and destroyed (along with all of its
// contents) when the guard instance is destroyed.
class ScopedTempDirectory {
 public:
  ScopedTempDirectory() { }
  ~ScopedTempDirectory() {
    if (!directory_.empty() && !file_util::Delete(directory_, true)) {
      LOG(DFATAL) << "Failed deleting temporary directory \""
                  << directory_.value() << "\"";
    }
  }
  // Creates a temporary directory.
  bool Initialize() {
    DCHECK(directory_.empty());
    if (!file_util::CreateNewTempDirectory(&kTempDirPrefix[0], &directory_)) {
      LOG(DFATAL) << "Failed creating temporary directory.";
      return false;
    }
    return true;
  }
  const FilePath& directory() const {
    DCHECK(!directory_.empty());
    return directory_;
  }
 private:
  FilePath directory_;
  DISALLOW_COPY_AND_ASSIGN(ScopedTempDirectory);
};  // class ScopedTempDirectory

// A helper class for manipulating a Chrome product version.
class ChromeVersion {
 public:
  static ChromeVersion FromHighLow(DWORD high, DWORD low) {
    return ChromeVersion(static_cast<ULONGLONG>(high) << 32 |
                         static_cast<ULONGLONG>(low));
  }
  ChromeVersion() { }
  explicit ChromeVersion(ULONGLONG value) : version_(value) { }
  WORD major() const { return static_cast<WORD>(version_ >> 48); }
  WORD minor() const { return static_cast<WORD>(version_ >> 32); }
  WORD build() const { return static_cast<WORD>(version_ >> 16); }
  WORD patch() const { return static_cast<WORD>(version_); }
  DWORD high() const { return static_cast<DWORD>(version_ >> 32); }
  DWORD low() const { return static_cast<DWORD>(version_); }
  ULONGLONG value() const { return version_; }
  void set_value(ULONGLONG value) { version_ = value; }
  std::wstring ToString() const;
 private:
  ULONGLONG version_;
};  // class ChromeVersion

std::wstring ChromeVersion::ToString() const {
  wchar_t buffer[24];
  int string_len =
      swprintf_s(&buffer[0], arraysize(buffer), L"%hu.%hu.%hu.%hu",
                 major(), minor(), build(), patch());
  DCHECK_NE(-1, string_len);
  DCHECK_GT(static_cast<int>(arraysize(buffer)), string_len);
  return std::wstring(&buffer[0], string_len);
}

// A read/write mapping of a file.
// Note: base::MemoryMappedFile is not used because it doesn't support
// read/write mappings.  Adding such support across all platforms for this
// Windows-only test code seems like overkill.
class MappedFile {
 public:
  MappedFile() : size_(), mapping_(), view_() { }
  ~MappedFile();
  bool Initialize(base::PlatformFile file);
  void* data() const { return view_; }
  size_t size() const { return size_; }
 private:
  size_t size_;
  HANDLE mapping_;
  void* view_;
  DISALLOW_COPY_AND_ASSIGN(MappedFile);
};  // class MappedFile

MappedFile::~MappedFile() {
  if (view_ != NULL) {
    EXPECT_NE(0, UnmapViewOfFile(view_));
  }
  if (mapping_ != NULL) {
    EXPECT_NE(0, CloseHandle(mapping_));
  }
}

bool MappedFile::Initialize(base::PlatformFile file) {
  DCHECK(mapping_ == NULL);
  bool result = false;
  base::PlatformFileInfo file_info;

  if (base::GetPlatformFileInfo(file, &file_info)) {
    if (file_info.size <=
        static_cast<int64>(std::numeric_limits<size_t>::max())) {
      mapping_ = CreateFileMapping(file, NULL, PAGE_READWRITE, 0,
                                   static_cast<DWORD>(file_info.size), NULL);
      if (mapping_ != NULL) {
        view_ = MapViewOfFile(mapping_, FILE_MAP_WRITE, 0, 0,
                              static_cast<size_t>(file_info.size));
        if (view_ != NULL) {
          result = true;
        } else {
          PLOG(DFATAL) << "MapViewOfFile failed";
        }
      } else {
        PLOG(DFATAL) << "CreateFileMapping failed";
      }
    } else {
      LOG(DFATAL) << "Files larger than " << std::numeric_limits<size_t>::max()
                  << " are not supported.";
    }
  } else {
    PLOG(DFATAL) << "GetPlatformFileInfo failed";
  }
  return result;
}

// Calls CreateProcess with good default parameters and waits for the process
// to terminate returning the process exit code.
bool RunProcessAndWait(const wchar_t* exe_path, const std::wstring& cmdline,
                       int* exit_code) {
  bool result = true;
  base::ProcessHandle process;
  if (base::LaunchApp(cmdline, true, true, &process)) {
    if (exit_code) {
      if (!GetExitCodeProcess(process,
                              reinterpret_cast<DWORD*>(exit_code))) {
        PLOG(DFATAL) << "Failed getting the exit code for \""
                     << cmdline << "\".";
        result = false;
      } else {
        DCHECK_NE(*exit_code, STILL_ACTIVE);
      }
    }
  } else {
    result = false;
  }

  CloseHandle(process);
  return result;
}

// Retrieves the version number of setup.exe in |work_dir| from its version
// resource, placing the value in |version|.  Returns true on success.
bool GetSetupExeVersion(const FilePath& work_dir, ChromeVersion* version) {
  DCHECK(version);
  bool result = false;
  upgrade_test::ResourceLoader setup;
  std::pair<const uint8*, DWORD> version_info_data;

  if (setup.Initialize(work_dir.Append(&kSetupExe[0])) &&
      setup.Load(VS_VERSION_INFO, reinterpret_cast<WORD>(RT_VERSION),
                 &version_info_data)) {
    const VS_FIXEDFILEINFO* fixed_file_info;
    UINT ver_info_len;
    if (VerQueryValue(version_info_data.first, L"\\",
                      reinterpret_cast<void**>(
                          const_cast<VS_FIXEDFILEINFO**>(&fixed_file_info)),
                      &ver_info_len) != 0) {
      DCHECK_EQ(sizeof(VS_FIXEDFILEINFO), static_cast<size_t>(ver_info_len));
      *version = ChromeVersion::FromHighLow(fixed_file_info->dwFileVersionMS,
                                            fixed_file_info->dwFileVersionLS);
      result = true;
    } else {
      LOG(DFATAL) << "VerQueryValue failed to retrieve VS_FIXEDFILEINFO";
    }
  }

  return result;
}

// Replace all occurrences in the sequence [|dest_first|, |dest_last) that
// equals [|src_first|, |src_last) with the sequence at |replacement_first| of
// the same length.  Returns true on success.  If non-NULL, |replacements_made|
// is set to true/false accordingly.
bool ReplaceAll(uint8* dest_first, uint8* dest_last,
                const uint8* src_first, const uint8* src_last,
                const uint8* replacement_first, bool* replacements_made) {
  bool result = true;
  bool changed = false;
  do {
    dest_first = std::search(dest_first, dest_last, src_first, src_last);
    if (dest_first == dest_last) {
      break;
    }
    changed = true;
    if (memcpy_s(dest_first, dest_last - dest_first,
                 replacement_first, src_last - src_first) != 0) {
      result = false;
      break;
    }
    dest_first += (src_last - src_first);
  } while (true);

  if (replacements_made != NULL) {
    *replacements_made = changed;
  }

  return result;
}

// A context structure in support of our EnumResource_Fn callback.
struct VisitResourceContext {
  ChromeVersion current_version;
  std::wstring current_version_str;
  ChromeVersion new_version;
  std::wstring new_version_str;
};  // struct VisitResourceContext

// Replaces the old version with the new in a resource.  A first pass is made to
// replace the string form (e.g., "9.0.584.0").  If any replacements are made, a
// second pass is made to replace the binary form (e.g., 0x0000024800000009).
void VisitResource(const upgrade_test::EntryPath& path,
                   uint8* data, DWORD size, DWORD code_page,
                   uintptr_t context) {
  VisitResourceContext& ctx = *reinterpret_cast<VisitResourceContext*>(context);

  // Replace all occurrences of current_version_str with new_version_str
  bool changing_version = false;
  if (ReplaceAll(
          data,
          data + size,
          reinterpret_cast<const uint8*>(ctx.current_version_str.c_str()),
          reinterpret_cast<const uint8*>(ctx.current_version_str.c_str() +
              ctx.current_version_str.size() + 1),
          reinterpret_cast<const uint8*>(ctx.new_version_str.c_str()),
          &changing_version) &&
      changing_version) {
    // Replace all occurrences of current_version with new_version
    struct VersionPair {
      DWORD high;
      DWORD low;
    };
    VersionPair cur_ver = {
      ctx.current_version.high(), ctx.current_version.low()
    };
    VersionPair new_ver = {
      ctx.new_version.high(), ctx.new_version.low()
    };
    ReplaceAll(data, data + size, reinterpret_cast<const uint8*>(&cur_ver),
               reinterpret_cast<const uint8*>(&cur_ver) + sizeof(cur_ver),
               reinterpret_cast<const uint8*>(&new_ver), NULL);
  }
}

// Updates the version strings and numbers in all of |image_file|'s resources.
bool UpdateVersionIfMatch(const FilePath& image_file,
                          VisitResourceContext* context) {
  bool result = false;
  base::win::ScopedHandle image_handle(base::CreatePlatformFile(
      image_file,
      (base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_READ |
       base::PLATFORM_FILE_WRITE | base::PLATFORM_FILE_EXCLUSIVE_READ |
       base::PLATFORM_FILE_EXCLUSIVE_WRITE), NULL, NULL));
  if (image_handle.Get() != INVALID_HANDLE_VALUE) {
    MappedFile image_mapping;
    if (image_mapping.Initialize(image_handle)) {
      base::win::PEImageAsData image(
          reinterpret_cast<HMODULE>(image_mapping.data()));
      // PEImage class does not support other-architecture images.
      if (image.GetNTHeaders()->OptionalHeader.Magic ==
          IMAGE_NT_OPTIONAL_HDR_MAGIC) {
        result = upgrade_test::EnumResources(
            image, &VisitResource, reinterpret_cast<uintptr_t>(context));
      } else {
        result = true;
      }
    }
  } else {
    PLOG(DFATAL) << "Failed to open \"" << image_file.value() << "\"";
  }
  return result;
}

// Raises or lowers the version of all .exe and .dll files in |work_dir| as well
// as the |work-dir|\Chrome-bin\w.x.y.z directory.  |original_version| and
// |new_version|, when non-NULL, are given the original and new version numbers
// on success.
bool ApplyAlternateVersion(const FilePath& work_dir,
                           upgrade_test::Direction direction,
                           std::wstring* original_version,
                           std::wstring* new_version) {
  VisitResourceContext ctx;
  if (!GetSetupExeVersion(work_dir, &ctx.current_version)) {
    return false;
  }
  ctx.current_version_str = ctx.current_version.ToString();

  // Figure out a past or future version with the same string length as this one
  // by decrementing or incrementing each component.
  LONGLONG incrementer = (direction == upgrade_test::PREVIOUS_VERSION ? -1 : 1);

  do {
    if (incrementer == 0) {
      LOG(DFATAL) << "Improbable version at the cusp of complete rollover";
      return false;
    }
    ctx.new_version.set_value(ctx.current_version.value() + incrementer);
    ctx.new_version_str = ctx.new_version.ToString();
    incrementer <<= 16;
  } while (ctx.new_version_str.size() != ctx.current_version_str.size());

  // Modify all .dll and .exe files with the current version.
  bool doing_great = true;
  file_util::FileEnumerator all_files(work_dir, true,
                                      file_util::FileEnumerator::FILES);
  do {
    FilePath file = all_files.Next();
    if (file.empty()) {
      break;
    }
    std::wstring extension = file.Extension();
    if (extension == &kExtExe[0] || extension == &kExtDll[0]) {
      doing_great = UpdateVersionIfMatch(file, &ctx);
    }
  } while (doing_great);

  // Change the versioned directory.
  FilePath chrome_bin = work_dir.Append(&kChromeBin[0]);
  doing_great = file_util::Move(chrome_bin.Append(ctx.current_version_str),
                                chrome_bin.Append(ctx.new_version_str));

  if (doing_great) {
    // Report the version numbers if requested.
    if (original_version != NULL)
      original_version->assign(ctx.current_version_str);
    if (new_version != NULL)
      new_version->assign(ctx.new_version_str);
  }

  return doing_great;
}

// Returns the path to the directory holding the 7za executable.  By default, it
// is assumed that the test resides in the tree's output directory, so the
// relative path "..\..\third_party\lzma_sdk\Executable" is applied to the host
// executable's directory.  This can be overridden with the --7za_path
// command-line switch.
FilePath Get7zaPath() {
  FilePath l7za_path = CommandLine::ForCurrentProcess()->GetSwitchValuePath(
      &kSwitch7zaPath[0]);
  if (l7za_path.empty()) {
    FilePath dir_exe;
    if (!PathService::Get(base::DIR_EXE, &dir_exe))
      LOG(DFATAL) << "Failed getting directory of host executable";
    l7za_path = dir_exe.Append(&k7zaPathRelative[0]);
  }
  return l7za_path;
}

bool CreateArchive(const FilePath& output_file, const FilePath& input_path,
                   int compression_level) {
  DCHECK(compression_level == 0 ||
         compression_level >= 1 && compression_level <= 9 &&
         (compression_level & 0x01) != 0);

  std::wstring command_line(1, L'"');
  command_line
      .append(Get7zaPath().Append(&k7zaExe[0]).value())
      .append(L"\" a -bd -t7z \"")
      .append(output_file.value())
      .append(L"\" \"")
      .append(input_path.value())
      .append(L"\" -mx")
      .append(1, L'0' + compression_level);
  int exit_code;
  if (!RunProcessAndWait(NULL, command_line, &exit_code))
    return false;
  if (exit_code != 0) {
    LOG(DFATAL) << Get7zaPath().Append(&k7zaExe[0]).value()
                << " exited with code " << exit_code
                << " while creating " << output_file.value();
    return false;
  }
  return true;
}

}  // namespace

namespace upgrade_test {

bool GenerateAlternateVersion(const FilePath& original_installer_path,
                              const FilePath& target_path,
                              Direction direction,
                              std::wstring* original_version,
                              std::wstring* new_version) {
  // Create a temporary directory in which we'll do our work.
  ScopedTempDirectory work_dir;
  if (!work_dir.Initialize())
    return false;

  // Copy the original mini_installer.
  FilePath mini_installer =
      work_dir.directory().Append(original_installer_path.BaseName());
  if (!file_util::CopyFile(original_installer_path, mini_installer)) {
    LOG(DFATAL) << "Failed copying \"" << original_installer_path.value()
                << "\" to \"" << mini_installer.value() << "\"";
    return false;
  }

  FilePath setup_ex_ = work_dir.directory().Append(&kSetupEx_[0]);
  FilePath chrome_packed_7z = work_dir.directory().Append(&kChromePacked7z[0]);
  // Load the original file and extract setup.ex_ and chrome.packed.7z
  {
    ResourceLoader resource_loader;
    std::pair<const uint8*, DWORD> resource_data;

    if (!resource_loader.Initialize(mini_installer))
      return false;

    // Write out setup.ex_
    if (!resource_loader.Load(&kSetupEx_[0], &kBl[0], &resource_data))
      return false;
    int written =
        file_util::WriteFile(setup_ex_,
                             reinterpret_cast<const char*>(resource_data.first),
                             static_cast<int>(resource_data.second));
    if (written != resource_data.second) {
      LOG(DFATAL) << "Failed writing \"" << setup_ex_.value() << "\"";
      return false;
    }

    // Write out chrome.packed.7z
    if (!resource_loader.Load(&kChromePacked7z[0], &kB7[0], &resource_data))
      return false;
    written =
        file_util::WriteFile(chrome_packed_7z,
                             reinterpret_cast<const char*>(resource_data.first),
                             static_cast<int>(resource_data.second));
    if (written != resource_data.second) {
      LOG(DFATAL) << "Failed writing \"" << chrome_packed_7z.value() << "\"";
      return false;
    }
  }

  // Expand setup.ex_
  FilePath setup_exe = setup_ex_.ReplaceExtension(&kExe[0]);
  std::wstring command_line;
  command_line.append(1, L'"')
    .append(&kExpandExe[0])
    .append(L"\" \"")
    .append(setup_ex_.value())
    .append(L"\" \"")
    .append(setup_exe.value())
    .append(1, L'\"');
  int exit_code;
  if (!RunProcessAndWait(NULL, command_line, &exit_code))
    return false;
  if (exit_code != 0) {
    LOG(DFATAL) << &kExpandExe[0] << " exited with code " << exit_code;
    return false;
  }

  // Unpack chrome.packed.7z
  std::wstring chrome_7z_name;
  if (LzmaUtil::UnPackArchive(chrome_packed_7z.value(),
                              work_dir.directory().value(),
                              &chrome_7z_name) != NO_ERROR) {
    LOG(DFATAL) << "Failed unpacking \"" << chrome_packed_7z.value() << "\"";
    return false;
  }

  // Unpack chrome.7z
  if (LzmaUtil::UnPackArchive(chrome_7z_name, work_dir.directory().value(),
                              NULL) != NO_ERROR) {
    LOG(DFATAL) << "Failed unpacking \"" << chrome_7z_name << "\"";
    return false;
  }

  // Get rid of intermediate files
  FilePath chrome_7z(chrome_7z_name);
  if (!file_util::Delete(chrome_7z, false) ||
      !file_util::Delete(chrome_packed_7z, false) ||
      !file_util::Delete(setup_ex_, false)) {
    LOG(DFATAL) << "Failed deleting intermediate files";
    return false;
  }

  // Increment the version in all files.
  ApplyAlternateVersion(work_dir.directory(), direction, original_version,
                        new_version);

  // Pack up files into chrome.7z
  if (!CreateArchive(chrome_7z, work_dir.directory().Append(&kChromeBin[0]), 0))
    return false;

  // Compress chrome.7z into chrome.packed.7z
  if (!CreateArchive(chrome_packed_7z, chrome_7z, 9))
    return false;

  // Compress setup.exe into setup.ex_
  command_line.assign(1, L'"')
      .append(&kMakeCab[0])
      .append(L"\" /D CompressionType=LZX /L \"")
      .append(work_dir.directory().value())
      .append(L"\" \"")
      .append(setup_exe.value());
  if (!RunProcessAndWait(NULL, command_line, &exit_code))
    return false;
  if (exit_code != 0) {
    LOG(DFATAL) << &kMakeCab[0] << " exited with code " << exit_code;
    return false;
  }

  // Replace the mini_installer's setup.ex_ and chrome.packed.7z resources.
  ResourceUpdater updater;
  if (!updater.Initialize(mini_installer) ||
      !updater.Update(&kSetupEx_[0], &kBl[0],
                      MAKELANGID(LANG_ENGLISH, SUBLANG_ENGLISH_US),
                      setup_ex_) ||
      !updater.Update(&kChromePacked7z[0], &kB7[0],
                      MAKELANGID(LANG_ENGLISH, SUBLANG_ENGLISH_US),
                      chrome_packed_7z) ||
      !updater.Commit()) {
    return false;
  }

  // Finally, move the updated mini_installer into place.
  return file_util::Move(mini_installer, target_path);
}

}  // namespace upgrade_test