-- hokey.hs: hOpenPGP key tool
-- Copyright © 2013-2014 Clint Adams
--
-- vim: softtabstop=4:shiftwidth=4:expandtab
--
-- This program is free software: you can redistribute it and/or modify
-- it under the terms of the GNU Affero General Public License as
-- published by the Free Software Foundation, either version 3 of the
-- License, or (at your option) any later version.
--
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-- GNU Affero General Public License for more details.
--
-- You should have received a copy of the GNU Affero General Public License
-- along with this program. If not, see <http://www.gnu.org/licenses/>.
{-# LANGUAGE DeriveGeneric #-}
import HOpenPGP.Tools.Common (banner, versioner, warranty)
import Codec.Encryption.OpenPGP.Fingerprint (fingerprint, eightOctetKeyID)
import Codec.Encryption.OpenPGP.KeyInfo (keySize)
import Codec.Encryption.OpenPGP.Signatures (verifyTK)
import Codec.Encryption.OpenPGP.Types
import Control.Applicative ((<$>),(<*>))
import Control.Arrow ((***), second)
import Control.Lens ((^.), (^?!), ix)
import Control.Monad.Trans.Writer.Lazy (execWriter, tell)
import qualified Data.Aeson as A
import qualified Data.ByteString as B
import qualified Data.ByteString.Lazy as BL
import Data.Conduit (($=),($$), runResourceT)
import qualified Data.Conduit.Binary as CB
import Data.Conduit.Cereal (conduitGet)
import qualified Data.Conduit.List as CL
import Data.Conduit.OpenPGP.Keyring (conduitToTKsDropping)
import Data.IxSet (empty, insert)
import Data.List (unfoldr, elemIndex, findIndex, sortBy)
import Data.Map (Map)
import qualified Data.Map as Map
import Data.Maybe (fromMaybe)
import Data.Monoid ((<>), mconcat)
import Data.Ord (comparing, Down(..))
import Data.Serialize (get)
import Data.Time.Clock.POSIX (getPOSIXTime, posixSecondsToUTCTime)
import Data.Time.Format (formatTime)
import GHC.Generics
import Options.Applicative.Builder (command, footer, header, help, info, long, metavar, prefs, progDesc, showDefault, showHelpOnError, option, subparser, value)
import Options.Applicative.Extra (customExecParser, helper)
import Options.Applicative.Types (Parser)
import System.IO (Handle, hFlush, hPutStrLn, stderr, stdin, hSetBuffering, BufferMode(..))
import System.Locale (defaultTimeLocale)
import Text.PrettyPrint.ANSI.Leijen (colon, green, indent, linebreak, list, putDoc, red, text, yellow, (<+>)) -- need 0.6.7 for hardline
data KAS = KAS {
pubkeyalgo :: PubKeyAlgorithm
, pubkeysize :: Int
} deriving Generic
data KeyReport = KeyReport {
keyStatus :: String
, keyFingerprint :: TwentyOctetFingerprint
, keyVer :: KeyVersion
, keyCreationTime :: TimeStamp
, keyAlgorithmAndSize :: KAS
, keySelfSigHashAlgorithms :: Map String [HashAlgorithm]
, keyPreferredHashAlgorithms :: Map String [[HashAlgorithm]]
, keyExpirationTimes :: Map String [[TimeStamp]]
} deriving Generic
instance A.ToJSON KAS
instance A.ToJSON KeyReport
instance A.ToJSON HashAlgorithm where
toJSON = A.toJSON . show
instance A.ToJSON PubKeyAlgorithm where
toJSON = A.toJSON . show
instance A.ToJSON KeyVersion where
toJSON DeprecatedV3 = A.toJSON (3 :: Int)
toJSON V4 = A.toJSON (4 :: Int)
instance A.ToJSON TwentyOctetFingerprint where
toJSON = A.toJSON . show
checkKey :: TK -> IO KeyReport
checkKey key = getPOSIXTime >>= \cpt -> return (KeyReport (either (const "not-good") (const "good") (processedTK cpt)) (fingerprint $ key^.tkPKP) (key^.tkPKP^.keyVersion) (key^.tkPKP^.timestamp) (KAS (key^.tkPKP^.pkalgo) (keySize (key^.tkPKP^.pubkey))) (Map.fromList (map (second has) ((processedOrOrig cpt)^.tkUIDs) ++ map (const "<uat>" *** has) ((processedOrOrig cpt)^.tkUAts))) (Map.fromList (map (second (map phas . alleged)) ((processedOrOrig cpt)^.tkUIDs) ++ map (const "<uat>" *** (map phas . alleged)) ((processedOrOrig cpt)^.tkUAts))) (Map.fromList (map (second (map kets . alleged)) ((processedOrOrig cpt)^.tkUIDs) ++ map (const "<uat>" *** (map kets . alleged)) ((processedOrOrig cpt)^.tkUAts))))
where
processedOrOrig = either (const key) id . processedTK
processedTK t = verifyTK (insert key empty) (Just (posixSecondsToUTCTime t)) . stripOlderSigs . stripOtherSigs $ key
sigissuer (SigVOther 2 _) = OtherSigSub 666 B.empty -- this is dumb
sigissuer (SigV3 {}) = OtherSigSub 666 B.empty -- this is dumb
sigissuer (SigV4 _ _ _ _ xs _ _) = xs^?!ix 0^.sspPayload -- this is a horrible stack of stupid assumptions
sigissuer (SigVOther _ _) = error "We're in the future."
sigissuer _ = error "WTF"
eoki = eightOctetKeyID . _tkPKP
hashAlgo (SigV4 _ _ x _ _ _ _) = x
phas (SigV4 _ _ _ xs _ _ _) = concatMap (\(SigSubPacket _ (PreferredHashAlgorithms x)) -> x) $ filter isPHA xs
isPHA (SigSubPacket _ (PreferredHashAlgorithms _)) = True
isPHA _ = False
kets (SigV4 _ _ _ xs _ _ _) = map (\(SigSubPacket _ (KeyExpirationTime x)) -> x) $ filter isKET xs
isKET (SigSubPacket _ (KeyExpirationTime _)) = True
isKET _ = False
has = map hashAlgo . alleged
isCT (SigSubPacket _ (SigCreationTime _)) = True
isCT _ = False
sigcts (SigV4 _ _ _ xs _ _ _) = map (\(SigSubPacket _ (SigCreationTime x)) -> x) $ filter isCT xs
alleged = filter (\x -> sigissuer x == Issuer (eoki key))
newest = take 1 . sortBy (comparing (Down . take 1 . sigcts)) -- FIXME: this is terrible
stripOtherSigs tk = tk {
_tkUIDs = map (second alleged) (_tkUIDs tk)
, _tkUAts = map (second alleged) (_tkUAts tk)
}
stripOlderSigs tk = tk {
_tkUIDs = map (second newest) (_tkUIDs tk)
, _tkUAts = map (second newest) (_tkUAts tk)
}
prettyKeyReport :: TK -> IO ()
prettyKeyReport key = getPOSIXTime >>= \cpt -> checkKey key >>= \keyReport -> putDoc . execWriter $ tell
( linebreak <> text "Key has potential validity:" <+> text (keyStatus keyReport)
<> linebreak <> text "Key has fingerprint:" <+> text (show (keyFingerprint keyReport))
<> linebreak <> text "Checking to see if key is OpenPGPv4:" <+> colorIf (green,red) (==V4) (keyVer keyReport)
<> linebreak <> (\kas -> text "Checking to see if key is RSA or DSA (>= 2048-bit):" <+> colorIf (green,yellow) (==RSA) (pubkeyalgo kas) <+> colorIf3 (green,yellow,red) (>= 3072) (>=2048) (pubkeysize kas)) (keyAlgorithmAndSize keyReport)
<> linebreak <> text "Checking self-sig hash algorithms (poorly):"
<> mconcat (map (\(x,ys) -> slpair x (listHAs ys)) (Map.toList (keySelfSigHashAlgorithms keyReport)))
<> linebreak <> text "Checking preferred hash algorithms (poorly):" -- FIXME
<> mconcat (map (\(x,ys) -> mlpair x listPHAs ys) (Map.toList (keyPreferredHashAlgorithms keyReport)))
<> linebreak <> text "Checking key expiration times based on" <+> text (formatTime defaultTimeLocale "%c" (posixSecondsToUTCTime . realToFrac $ (key^.tkPKP^.timestamp))) <+> text "(creation) and" <+> text (formatTime defaultTimeLocale "%c" (posixSecondsToUTCTime cpt)) <+> text "(current) times (poorly):" -- FIXME
<> mconcat (map (\(x,ys) -> mlpair x (listKETs cpt (keyCreationTime keyReport)) ys) (Map.toList (keyExpirationTimes keyReport)))
<> linebreak
)
where
colorIf (y,n) p x = ((if p x then y else n) . text . show) x
colorIf3 (g,y,r) p1 p2 x = ((if p1 x then g else (if p2 x then y else r)) . text . show) x
slpair x y = linebreak <> indent 2 (text x <> colon <+> y)
mlpair x f ys = linebreak <> indent 2 (text x) <> colon <> mconcat (map ((linebreak <>) . indent 4 . f) ys)
listHAs = list . map (\x -> ((if x `elem` [DeprecatedMD5, SHA1] then red else id) . text . show) x)
listPHAs x = (if fSHA2Family x < ei DeprecatedMD5 x && fSHA2Family x < ei SHA1 x then green else red) . list . map (text . show) $ x
listKETs ct ts x = colorExpiration ct ts x . list . map (text . keyExp ts) $ x
fSHA2Family = fi (`elem` [SHA512,SHA384,SHA256,SHA224])
ei x y = fromMaybe maxBound (elemIndex x y)
fi x y = fromMaybe maxBound (findIndex x y)
colorExpiration ct ts kes
| null kes = red
| any (\ke -> realToFrac ts + realToFrac ke < ct) kes = red
| any (\ke -> realToFrac ts + realToFrac ke > ct + (5*31557600)) kes = yellow
| otherwise = green
keyExp ts ke = durationPrettyPrinter ke ++ " = " ++ formatTime defaultTimeLocale "%c" (posixSecondsToUTCTime (realToFrac ts + realToFrac ke))
jsonReport :: TK -> IO ()
jsonReport key = checkKey key >>= \keyReport -> BL.putStr (A.encode keyReport)
-- this does not have the same sense of calendar anyone else might
durationPrettyPrinter :: TimeStamp -> String
durationPrettyPrinter = concat . unfoldr durU
where
durU x
| x >= 31557600 = Just ((++"y") . show $ x `div` 31557600, x `mod` 31557600)
| x >= 2629800 = Just ((++"m") . show $ x `div` 2629800, x `mod` 2629800)
| x >= 86400 = Just ((++"d") . show $ x `div` 86400, x `mod` 86400)
| x > 0 = Just ((++"s") . show $ x, 0)
| otherwise = Nothing
data OutputFormat = Pretty | JSON
deriving (Eq, Read, Show)
data Options = Options {
outputFormat :: OutputFormat
}
data Command = Lint Options
lintO :: Parser Options
lintO = Options
<$> option
( long "output-format"
<> metavar "FORMAT"
<> value Pretty
<> showDefault
<> help "output format" )
dispatch :: Command -> IO ()
dispatch (Lint o) = banner' stderr >> hFlush stderr >> doLint o
main :: IO ()
main = do
hSetBuffering stderr LineBuffering
customExecParser (prefs showHelpOnError) (info (helper <*> versioner <*> cmd) (header (banner "hokey") <> progDesc "hOpenPGP Key utility" <> footer (warranty "hokey"))) >>= dispatch
cmd :: Parser Command
cmd = subparser
( command "lint" (info ( Lint <$> lintO) ( progDesc "check key(s) for 'best practices'" )))
doLint :: Options -> IO ()
doLint o = do
keys <- runResourceT $ CB.sourceHandle stdin $= conduitGet get $= conduitToTKsDropping $$ CL.consume
mapM_ (output (outputFormat o)) keys
where
output Pretty = prettyKeyReport
output JSON = jsonReport
banner' :: Handle -> IO ()
banner' h = hPutStrLn h (banner "hokey" ++ "\n" ++ warranty "hokey")