Pgp conversion in sftp

Hi Friends,

i am using SFTP adapter and pgp addon also

my structure is like that

MM_name

  header

     aaaa---- this or fields

     bbbb

Details

        ccc

        ddd

lineitems

      ffffff

      gggg

      hhhhh

      jjjjjj

i got flat file with pgp encryption data, pipe delimited, endseparator is pipe,its not fixed lenth

So  I need to decrypt the data and i declare the message tranferbeen,

So how can i Declare for this Structure.

Thanks and regards.