import Crypto.Hash
import Crypto.PubKey.RSA
import Data.X509
import Data.X509.PKCS10
main :: IO ()
main = do
let rsaKeySize = 128
let publicExponent = 3
(pubKey, privKey) <- generate rsaKeySize publicExponent
let subjectAttrs = makeX520Attributes [(X520CommonName, "node.fcomb.io"), (X520OrganizationName, "fcomb")]
let extAttrs = PKCS9Attributes [PKCS9Attribute $ ExtBasicConstraints False Nothing, PKCS9Attribute $ ExtKeyUsage [KeyUsage_digitalSignature,KeyUsage_nonRepudiation,KeyUsage_keyEncipherment]]
Right req <- generateCSR subjectAttrs extAttrs (KeyPairRSA pubKey privKey) SHA512
putStrLn . show . toPEM $ req -- export in PEM format
putStrLn . show $ verify (csrToSigned req) $ PubKeyRSA pubKey -- sign CSR before verifying