I have a Java application (an ESB - Enterprise Service Bus) which deals with customer sensitive data and have a requirement of supporting Data encryption at rest in order to prevent data abuse.
The application stores customer data for processing on the file system and application interacts with it through java.io.File API. So basically, I need to encrypt the file before it is persisted on the file system by the application and then decrypt it before application reads it so that it can be parsed and processed.
Are there any good frameworks or libraries that can help me implement Data encryption at rest? I am planning to use PGP encryption/decryption for implementing Data encryption at rest.
I am looking for best and recommended approach for implementing Data encryption at rest within my Java application and any help shall be appreciated.
Why on Earth would you think pgp is the right tool for this? Seems to me that you only need a symmetric key solution, so pgp feels like the wrong answer.
Cryptography in Java is a minefield. Easy to do things wrong, hard to do things right.
Having said that, you have a better chance to not screwing up if you use BouncyCastle rather than something else. They have example code that shows you how to do various operations.
For encrypting data at rest, I recommend you use AES in either CBC mode or CTR mode. If using CBC mode, make sure you choose your IV in a cryptographic secure way (unpredictable). Also, never re-use an IV for any mode of operation.
You should also consider whether you need message integrity. General guidance about symmetric encryption here.
Even though people often get crypto wrong, the bigger problem is key management. That's a whole new can of worms (and don't be fooled into thinking pgp provides a solution to this: all it does is shifts the problem to somewhere else).