convert StorableCipher to ByteString

This allows getting rid of the ugly and error prone handling of
"bag of bytes" String in Remote.Helper.Encryptable.
Avoiding breakage like that dealt with by commit
9862d64bf9

And allows converting Utility.Gpg to use ByteString for IO, which is
a welcome change.

Tested the new git-annex interoperability with old, using all 3
encryption= types.

Sponsored-By: the NIH-funded NICEMAN (ReproNim TR&D3) project

Utility/Gpg.hs

@@ -1,10 +1,11 @@
 {- gpg interface
  -
- - Copyright 2011-2022 Joey Hess <id@joeyh.name>
+ - Copyright 2011-2023 Joey Hess <id@joeyh.name>
  -
  - License: BSD-2-clause
  -}
 
+{-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE CPP #-}
 
 module Utility.Gpg (
@@ -48,6 +49,7 @@ import Utility.Format (decode_c)
 
 import Control.Concurrent.Async
 import Control.Monad.IO.Class
+import qualified Data.ByteString as B
 import qualified Data.Map as M
 import Data.Char
 
@@ -108,10 +110,10 @@ stdEncryptionParams symmetric = enc symmetric ++
 		]
 
 {- Runs gpg with some params and returns its stdout, strictly. -}
-readStrict :: GpgCmd -> [CommandParam] -> IO String
+readStrict :: GpgCmd -> [CommandParam] -> IO B.ByteString
 readStrict c p = readStrict' c p Nothing
 
-readStrict' :: GpgCmd -> [CommandParam] -> Maybe [(String, String)] -> IO String
+readStrict' :: GpgCmd -> [CommandParam] -> Maybe [(String, String)] -> IO B.ByteString
 readStrict' (GpgCmd cmd) params environ = do
 	params' <- stdParams params
 	let p = (proc cmd params')
@@ -120,17 +122,16 @@ readStrict' (GpgCmd cmd) params environ = do
 		}
 	withCreateProcess p (go p)
   where
-	go p _ (Just hout) _ pid = do
-		hSetBinaryMode hout True
-		forceSuccessProcess p pid `after` hGetContentsStrict hout
+	go p _ (Just hout) _ pid =
+		forceSuccessProcess p pid `after` B.hGetContents hout
 	go _ _ _ _ _ = error "internal"
 
 {- Runs gpg, piping an input value to it, and returning its stdout,
  - strictly. -}
-pipeStrict :: GpgCmd -> [CommandParam] -> String -> IO String
+pipeStrict :: GpgCmd -> [CommandParam] -> B.ByteString -> IO B.ByteString
 pipeStrict c p i = pipeStrict' c p Nothing i
 
-pipeStrict' :: GpgCmd -> [CommandParam] -> Maybe [(String, String)] -> String -> IO String
+pipeStrict' :: GpgCmd -> [CommandParam] -> Maybe [(String, String)] -> B.ByteString -> IO B.ByteString
 pipeStrict' (GpgCmd cmd) params environ input = do
 	params' <- stdParams params
 	let p = (proc cmd params')
@@ -141,11 +142,9 @@ pipeStrict' (GpgCmd cmd) params environ input = do
 	withCreateProcess p (go p)
   where
 	go p (Just to) (Just from) _ pid = do
-		hSetBinaryMode to True
-		hSetBinaryMode from True
-		hPutStr to input
+		B.hPutStr to input
 		hClose to
-		forceSuccessProcess p pid `after` hGetContentsStrict from
+		forceSuccessProcess p pid `after` B.hGetContents from
 	go _ _ _ _ _ = error "internal"
 
 {- Runs gpg with some parameters. First sends it a passphrase (unless it
@@ -158,7 +157,7 @@ pipeStrict' (GpgCmd cmd) params environ input = do
  - the passphrase.
  -
  - Note that the reader must fully consume gpg's input before returning. -}
-feedRead :: (MonadIO m, MonadMask m) => GpgCmd -> [CommandParam] -> String -> (Handle -> IO ()) -> (Handle -> m a) -> m a
+feedRead :: (MonadIO m, MonadMask m) => GpgCmd -> [CommandParam] -> B.ByteString -> (Handle -> IO ()) -> (Handle -> m a) -> m a
 feedRead cmd params passphrase feeder reader = do
 #ifndef mingw32_HOST_OS
 	let setup = liftIO $ do
@@ -166,7 +165,7 @@ feedRead cmd params passphrase feeder reader = do
 		(frompipe, topipe) <- System.Posix.IO.createPipe
 		toh <- fdToHandle topipe
 		t <- async $ do
-			hPutStrLn toh passphrase
+			B.hPutStr toh (passphrase <> "\n")
 			hClose toh
 		let Fd pfd = frompipe
 		let passphrasefd = [Param "--passphrase-fd", Param $ show pfd]
@@ -180,7 +179,7 @@ feedRead cmd params passphrase feeder reader = do
 #else
 	-- store the passphrase in a temp file for gpg
 	withTmpFile "gpg" $ \tmpfile h -> do
-		liftIO $ hPutStr h passphrase
+		liftIO $ B.hPutStr h passphrase
 		liftIO $ hClose h
 		let passphrasefile = [Param "--passphrase-file", File tmpfile]
 		go $ passphrasefile ++ params
@@ -223,7 +222,8 @@ findPubKeys' cmd environ for
 	-- pass forced subkey through as-is rather than
 	-- looking up the master key.
 	| isForcedSubKey for = return $ KeyIds [for]
-	| otherwise = KeyIds . parse . lines <$> readStrict' cmd params environ
+	| otherwise = KeyIds . parse . lines . decodeBS
+		<$> readStrict' cmd params environ
   where
 	params = [Param "--with-colons", Param "--list-public-keys", Param for]
 	parse = mapMaybe (keyIdField . splitc ':')
@@ -241,7 +241,8 @@ type UserId = String
 secretKeys :: GpgCmd -> IO (M.Map KeyId UserId)
 secretKeys cmd = catchDefaultIO M.empty makemap
   where
-	makemap = M.fromList . parse . lines <$> readStrict cmd params
+	makemap = M.fromList . parse . lines . decodeBS
+		<$> readStrict cmd params
 	params = [Param "--with-colons", Param "--list-secret-keys", Param "--fixed-list-mode"]
 	parse = extract [] Nothing . map (splitc ':')
 	extract c (Just keyid) (("uid":_:_:_:_:_:_:_:_:userid:_):rest) =
@@ -301,7 +302,7 @@ genSecretKey (GpgCmd cmd) keytype passphrase userid keysize =
 {- Creates a block of high-quality random data suitable to use as a cipher.
  - It is armored, to avoid newlines, since gpg only reads ciphers up to the
  - first newline. -}
-genRandom :: GpgCmd -> Bool -> Size -> IO String
+genRandom :: GpgCmd -> Bool -> Size -> IO B.ByteString
 genRandom cmd highQuality size = do
 	s <- readStrict cmd params
 	checksize s
@@ -327,7 +328,7 @@ genRandom cmd highQuality size = do
 	 - entropy. -}
 	expectedlength = size * 8 `div` 6
 
-	checksize s = let len = length s in
+	checksize s = let len = B.length s in
 		unless (len >= expectedlength) $
 			shortread len
 
@@ -439,8 +440,8 @@ testHarness tmpdir cmd a = ifM (inSearchPath (unGpgCmd cmd))
 		liftIO $ void $ tryIO $ modifyFileMode (toRawFilePath subdir) $
 			removeModes $ otherGroupModes
 		-- For some reason, recent gpg needs a trustdb to be set up.
-		_ <- pipeStrict' cmd [Param "--trust-model", Param "auto", Param "--update-trustdb"] (Just environ) []
-		_ <- pipeStrict' cmd [Param "--import", Param "-q"] (Just environ) $ unlines
+		_ <- pipeStrict' cmd [Param "--trust-model", Param "auto", Param "--update-trustdb"] (Just environ) mempty
+		_ <- pipeStrict' cmd [Param "--import", Param "-q"] (Just environ) $ encodeBS $ unlines
 			[testSecretKey, testKey]
 		return environ
 		
@@ -470,7 +471,7 @@ checkEncryptionFile cmd environ filename keys =
   where
 	params = [Param "--list-packets", Param "--list-only", File filename]
 
-checkEncryptionStream :: GpgCmd -> Maybe [(String, String)] -> String -> Maybe KeyIds -> IO Bool
+checkEncryptionStream :: GpgCmd -> Maybe [(String, String)] -> B.ByteString -> Maybe KeyIds -> IO Bool
 checkEncryptionStream cmd environ stream keys =
 	checkGpgPackets cmd environ keys =<< pipeStrict' cmd params environ stream
   where
@@ -480,13 +481,13 @@ checkEncryptionStream cmd environ stream keys =
  - symmetrically encrypted (keys is Nothing), or encrypted to some
  - public key(s).
  - /!\ The key needs to be in the keyring! -}
-checkGpgPackets :: GpgCmd -> Maybe [(String, String)] -> Maybe KeyIds -> String -> IO Bool
+checkGpgPackets :: GpgCmd -> Maybe [(String, String)] -> Maybe KeyIds -> B.ByteString -> IO Bool
 checkGpgPackets cmd environ keys str = do
 	let (asym,sym) = partition (pubkeyEncPacket `isPrefixOf`) $
 			filter (\l' -> pubkeyEncPacket `isPrefixOf` l' ||
 				symkeyEncPacket `isPrefixOf` l') $
 			takeWhile (/= ":encrypted data packet:") $
-			lines str
+			lines (decodeBS str)
 	case (keys,asym,sym) of
 		(Nothing, [], [_]) -> return True
 		(Just (KeyIds ks), ls, []) -> do