Checksum or validate .tar file contents with directory in shell

Scenario: Using Linux shell to back up a directory of many sub files and compressing the data with ‘tar -cvpJf filename.tar /savedir/’. Goal: Using shell — checksum or validate the newly created ‘.tar’ against the original directory. Limitations: Solution cannot involve downloading 3rd party support libraries. User cannot be part of the process. Comments: Basically, I am wondering if there is a tar flag I am missing that will validate upon creation of the tar, or maybe I can pipe the tar into some process?