I'm working on a Go peer-to-peer chat service to be used in Hyperboria, which operates as a meshnet. That is relatively unimportant compared to my problem:
I need to use OpenPGP keys existent in user's GPG keyrings in order to encrypt and decrypt messages. I need to be able to discover public and private keys, check that given key IDs are present, and use them to either encrypt or decrypt []byte, (either before or after it goes across a TCP connection)
Is there a package that I could look into to do this?
You should check out the go.crypto packages particularly the ones in: http://code.google.com/p/go/source/browse/?repo=crypto#hg%2Fopenpgp
It's the most likely to have what you are looking for.