Just like crypto-pubkey-openssh but not dependent on crypto-pubkey-types nor any specific crypto library.
At the moment only supports public RSA keys.
Can be easily used with cryptonite like so:
import Crypto.PubKey.SSH (decodeSshPubKey)
import Crypto.PubKey.RSA (PublicKey (..))
import Data.ByteString.Lazy.Char8 as LBS
decodeSshPubKey PublicKey <$> LBS.readFile ".ssh/id_rsa.pub"