diff options
Diffstat (limited to 'Crypto.hs')
| -rw-r--r-- | Crypto.hs | 21 |
1 files changed, 14 insertions, 7 deletions
@@ -78,15 +78,22 @@ genSharedCipher :: Bool -> IO StorableCipher genSharedCipher highQuality = SharedCipher <$> Gpg.genRandom highQuality cipherSize -{- Updates an existing Cipher, re-encrypting it to add a keyid. -} -updateEncryptedCipher :: String -> StorableCipher -> IO StorableCipher -updateEncryptedCipher _ (SharedCipher _) = undefined -updateEncryptedCipher keyid encipher@(EncryptedCipher _ ks) = do - ks' <- Gpg.findPubKeys keyid +{- Updates an existing Cipher, re-encrypting it to add or remove keyids, + - depending on whether the first component is True or False. -} +updateEncryptedCipher :: [(Bool, String)] -> StorableCipher -> IO StorableCipher +updateEncryptedCipher _ SharedCipher{} = undefined +updateEncryptedCipher [] encipher = return encipher +updateEncryptedCipher newkeys encipher@(EncryptedCipher _ (KeyIds ks)) = do + dropKeys <- listKeyIds [ k | (False, k) <- newkeys ] + forM_ dropKeys $ \k -> unless (k `elem` ks) $ + error $ "Key " ++ k ++ " is not granted access." + addKeys <- listKeyIds [ k | (True, k) <- newkeys ] + let ks' = (addKeys ++ ks) \\ dropKeys + when (null ks') $ error "The new access list would become empty." cipher <- decryptCipher encipher - encryptCipher cipher (merge ks ks') + encryptCipher cipher $ KeyIds ks' where - merge (KeyIds a) (KeyIds b) = KeyIds $ a ++ b + listKeyIds = mapM (Gpg.findPubKeys >=*> keyIds) >=*> concat describeCipher :: StorableCipher -> String describeCipher (SharedCipher _) = "shared cipher" |