PGP (Pretty Good Privacy)

PGP is an encryption program that provides cryptographic privacy and authentication for data communication.

Decrypt

First off, you need to format the private key to make the John to recognize it.

gpg2john private.key > hash.txt

Crack the passphrase using John the Ripper.

john --wordlist=wordlist.txt hash.txt

Decode Public Key

There are some online tools.

• PGPDump