# File lib/dnsruby/resource/NSEC3.rb, line 19
  def encode32hex(str)
    str.gsub(/\G(.{5})|(.{1,4}\z)/mn) do
      full = $1; frag = $2
      n, c = (full || frag.ljust(5, "\0")).unpack('NC')
      full = ((n << 8) | c).to_s(32).rjust(8, '0')
      if frag
        full[0, (frag.length * 8 + 4).div(5)].ljust(8, '=').upcase
      else
        full.upcase
      end
    end
  end