text: // Copyright 2018 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 <windows.h>
  
  #include <string>
  #include <vector>
  
  #include "base/files/file_path.h"
  #include "base/strings/string_piece.h"
  #include "base/strings/string_split.h"
  #include "base/strings/string_util.h"
  #include "base/win/scoped_handle.h"
  #include "base/win/windows_version.h"
  #include "components/services/quarantine/common.h"
  #include "components/services/quarantine/common_win.h"
  #include "components/services/quarantine/test_support.h"
  
  namespace quarantine {
  
  namespace {
  
  bool ZoneIdentifierPresentForFile(const base::FilePath& path,
                                    const GURL source_url,
                                    const GURL referrer_url) {
    const DWORD kShare = FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
    base::FilePath::StringType zone_identifier_path =
        path.value() + kZoneIdentifierStreamSuffix;
    base::win::ScopedHandle file(
        ::CreateFile(zone_identifier_path.c_str(), GENERIC_READ, kShare, nullptr,
                     OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, nullptr));
    if (!file.IsValid())
      return false;
  
    // During testing, the zone identifier is expected to be under this limit.
    std::vector<char> zone_identifier_contents_buffer(4096);
    DWORD actual_length = 0;
    if (!::ReadFile(file.Get(), &zone_identifier_contents_buffer.front(),
                    zone_identifier_contents_buffer.size(), &actual_length,
                    nullptr))
      return false;
    zone_identifier_contents_buffer.resize(actual_length);
  
    std::string zone_identifier_contents(zone_identifier_contents_buffer.begin(),
                                         zone_identifier_contents_buffer.end());
  
    std::vector<base::StringPiece> lines =
        base::SplitStringPiece(zone_identifier_contents, "\n",
                               base::TRIM_WHITESPACE, base::SPLIT_WANT_NONEMPTY);
    if (lines.size() < 2 || lines[0] != "[ZoneTransfer]" != 0)
      return false;
  
    base::StringPiece found_zone_id;
    base::StringPiece found_host_url;
    base::StringPiece found_referrer_url;
  
    // Note that we don't try too hard to parse the zone identifier here. This is
    // a test. If Windows starts adding whitespace or doing anything fancier than
    // ASCII, then we'd have to update this.
    for (const auto& line : lines) {
      if (base::StartsWith(line, "ZoneId="))
        found_zone_id = line.substr(7);
      else if (base::StartsWith(line, "HostUrl="))
        found_host_url = line.substr(8);
      else if (base::StartsWith(line, "ReferrerUrl="))
        found_referrer_url = line.substr(12);
    }
  
    return !found_zone_id.empty() &&
           (source_url.is_empty() ||
            SanitizeUrlForQuarantine(source_url).spec() == found_host_url) &&
           (referrer_url.is_empty() ||
            SanitizeUrlForQuarantine(referrer_url).spec() == found_referrer_url);
  }
  
  }  // namespace
  
  bool IsFileQuarantined(const base::FilePath& file,
                         const GURL& source_url,
                         const GURL& referrer_url) {
    if (base::win::GetVersion() >= base::win::Version::WIN10)
      return ZoneIdentifierPresentForFile(file, source_url, referrer_url);
    else
      return ZoneIdentifierPresentForFile(file, GURL::EmptyGURL(),
                                          GURL::EmptyGURL());
  }
  
  }  // namespace quarantine
  