path: root/kiki.hs

{-# LANGUAGE DoAndIfThenElse #-}
{-# LANGUAGE ViewPatterns  #-}
{-# LANGUAGE TupleSections #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE DeriveDataTypeable #-}
{-# LANGUAGE CPP #-}
module Main where

import Debug.Trace
import GHC.Exts (Down(..))
import Data.Tuple
import Data.Binary
import Data.OpenPGP
import qualified Data.ByteString.Lazy as L
import qualified Data.ByteString.Lazy.Char8 as Char8
import qualified Data.ByteString      as S
import qualified Data.ByteString.Char8 as S8
import Control.Monad
import qualified Text.Show.Pretty as PP
import Text.PrettyPrint as PP hiding ((<>))
import Data.List
import Data.OpenPGP.CryptoAPI
import Data.Ord
import Data.Maybe
import Data.Bits
import qualified Data.Text as T
import Data.Text.Encoding
import qualified Codec.Binary.Base32 as Base32
import qualified Codec.Binary.Base64 as Base64
import qualified Crypto.Hash.SHA1 as SHA1
import Data.Char (toLower)
import qualified Crypto.PubKey.RSA as RSA
import Crypto.Random (newGenIO,SystemRandom)
import Data.ASN1.Types
import Data.ASN1.Encoding
import Data.ASN1.BinaryEncoding
import Data.ASN1.BitArray
import Control.Applicative
import System.Environment
import System.Directory
import System.Exit
import ControlMaybe
import Data.Char
import Control.Arrow (second)
import Data.Traversable hiding (mapM)
import System.Console.CmdArgs
-- import System.Posix.Time
import Data.Time.Clock.POSIX
import System.Posix.IO (fdToHandle,fdRead)
import System.Posix.Files
import Data.Monoid ((<>))
-- import Data.X509
import qualified Data.Map as Map
import DotLock
import System.IO (hPutStrLn,stderr)


warn str = hPutStrLn stderr str

unprefix c spec = if null (snd p) then swap p else (fst p, tail (snd p))
 where p = break (==c) spec


data RSAPublicKey = RSAKey MPI MPI deriving Show
data PKCS8_RSAPublicKey = RSAKey8 MPI MPI deriving Show

pkcs8 (RSAKey n e) = RSAKey8 n e

instance ASN1Object RSAPublicKey where
    -- PKCS #1 RSA Public Key
    toASN1 (RSAKey (MPI n) (MPI e))
                  = \xs -> Start Sequence
                         : IntVal n
                         : IntVal e
                         : End Sequence
                         : xs
    fromASN1 _ =
        Left "fromASN1: RSAPublicKey: unexpected format"

instance ASN1Object PKCS8_RSAPublicKey where

    -- PKCS #8 Public key data
    toASN1 (RSAKey8 (MPI n) (MPI e))
                  = \xs -> Start Sequence
                         : Start Sequence
                         : OID [1,2,840,113549,1,1,1]
                         : End Sequence
                         : BitString (toBitArray bs 0)
                         : End Sequence
                         : xs
        where
            pubkey = Start Sequence : IntVal n : IntVal e : End Sequence : []
            bs = encodeASN1' DER pubkey

    fromASN1 (Start Sequence:IntVal modulus:IntVal pubexp:End Sequence:xs) =
        Right (RSAKey8 (MPI modulus) (MPI pubexp) , xs)
    fromASN1 (Start Sequence:Start Sequence:OID [1,2,840,113549,1,1,1]:End Sequence:BitString b:End Sequence:xs) =
        case decodeASN1' DER bs of
            Right as -> fromASN1 as
            Left e -> Left ("fromASN1: RSAPublicKey: "++show e)
      where
        BitArray _ bs = b

    fromASN1 _ =
        Left "fromASN1: RSAPublicKey: unexpected format"

data RSAPrivateKey = RSAPrivateKey
    { rsaN :: MPI
    , rsaE :: MPI
    , rsaD :: MPI
    , rsaP :: MPI
    , rsaQ :: MPI
    , rsaDmodP1 :: MPI
    , rsaDmodQminus1 :: MPI
    , rsaCoefficient :: MPI
    }
 deriving Show

{-
RSAPrivateKey ::= SEQUENCE {
  version           Version,
  modulus           INTEGER,  -- n
  publicExponent    INTEGER,  -- e
  privateExponent   INTEGER,  -- d
  prime1            INTEGER,  -- p
  prime2            INTEGER,  -- q
  exponent1         INTEGER,  -- d mod (p1)
  exponent2         INTEGER,  -- d mod (q-1)
  coefficient       INTEGER,  -- (inverse of q) mod p
  otherPrimeInfos   OtherPrimeInfos OPTIONAL
}
-}

instance ASN1Object RSAPrivateKey where
    toASN1 rsa@(RSAPrivateKey {})
        = \xs -> Start Sequence
               : IntVal 0
               : mpiVal rsaN
               : mpiVal rsaE
               : mpiVal rsaD
               : mpiVal rsaP
               : mpiVal rsaQ
               : mpiVal rsaDmodP1
               : mpiVal rsaDmodQminus1
               : mpiVal rsaCoefficient
               : End Sequence
               : xs
                  where mpiVal f = IntVal x where MPI x = f rsa

    fromASN1 ( Start Sequence
             : IntVal _ -- version
             : IntVal n
             : IntVal e
             : IntVal d
             : IntVal p
             : IntVal q
             : IntVal dmodp1
             : IntVal dmodqminus1
             : IntVal coefficient
             : ys) =
        Right ( privkey, tail $ dropWhile notend ys)
         where
            notend (End Sequence) = False
            notend _              = True
            privkey = RSAPrivateKey
                { rsaN = MPI n
                , rsaE = MPI e
                , rsaD = MPI d
                , rsaP = MPI p
                , rsaQ = MPI q
                , rsaDmodP1 = MPI dmodp1
                , rsaDmodQminus1 = MPI dmodqminus1
                , rsaCoefficient = MPI coefficient
                }
    fromASN1 _ =
        Left "fromASN1: RSAPrivateKey: unexpected format"

rsaKeyFromPacket p@(PublicKeyPacket {}) = do
    n <- lookup 'n' $ key p
    e <- lookup 'e' $ key p
    return $ RSAKey n e
rsaKeyFromPacket p@(SecretKeyPacket {}) = do
    n <- lookup 'n' $ key p
    e <- lookup 'e' $ key p
    return $ RSAKey n e
rsaKeyFromPacket _ = Nothing
derRSA rsa = do
    k <- rsaKeyFromPacket rsa
    return $ encodeASN1 DER (toASN1 k [])

getPackets :: IO [Packet]
getPackets = do
    input <- L.getContents
    case decodeOrFail input of
        Right (_,_,Message pkts) -> return pkts
        Left  (_,_,_)            -> return []


secretToPublic pkt@(SecretKeyPacket {}) =
    PublicKeyPacket { version = version pkt
                    , timestamp = timestamp pkt
                    , key_algorithm = key_algorithm pkt
                    , key = let seckey = key pkt
                                pubs = public_key_fields (key_algorithm pkt)
                            in filter (\(k,v) -> k `elem` pubs) seckey
                    , is_subkey = is_subkey pkt
                    , v3_days_of_validity = Nothing
                    }
secretToPublic pkt = pkt


extractPEM typ pem = dta
 where
    dta = case ys of
            _:dta_lines -> Char8.concat dta_lines
            []          -> ""
    xs = dropWhile (/="-----BEGIN " <> typ <> "-----") (Char8.lines pem)
    ys = takeWhile (/="-----END " <> typ <> "-----") xs

isKey (PublicKeyPacket {}) = True
isKey (SecretKeyPacket {}) = True
isKey _                    = False

isUserID (UserIDPacket {}) = True
isUserID _                 = False

isEmbeddedSignature (EmbeddedSignaturePacket {}) = True
isEmbeddedSignature _                            = False

isCertificationSig (CertificationSignature {}) = True
isCertificationSig _                           = True

isTrust (TrustPacket {}) = True
isTrust _                = False

issuer (IssuerPacket issuer) = Just issuer
issuer _                     = Nothing
backsig (EmbeddedSignaturePacket s) = Just s
backsig _                           = Nothing

isSubkeySignature (SubkeySignature {}) = True
isSubkeySignature _                    = False

isPublicMaster k@(PublicKeyPacket {}) = not $ is_subkey k
isPublicMaster _ = False

now = floor <$> Data.Time.Clock.POSIX.getPOSIXTime

usage (NotationDataPacket
        { human_readable = True
        , notation_name  = "usage@"
        , notation_value = u
        }) = Just u
usage _    = Nothing

verifyBindings keys nonkeys = (top ++ filter isSubkeySignature embedded,othersigs)
 where
    verified = do
        sig <- signatures (Message nonkeys)
        let v = verify (Message keys) sig
        guard (not . null $ signatures_over v)
        return v
    (top,othersigs) = partition isSubkeySignature verified
    embedded = do
        sub <- top
        let sigover = signatures_over sub
            unhashed = sigover >>= unhashed_subpackets
            subsigs = mapMaybe backsig unhashed
            -- This should consist only of 0x19 values
            -- subtypes = map signature_type subsigs
        -- trace ("subtypes = "++show subtypes) (return ())
        -- trace ("issuers: "++show (map signature_issuer subsigs)) (return ())
        sig <- signatures (Message ([topkey sub,subkey sub]++subsigs))
        let v = verify (Message [subkey sub]) sig
        guard (not . null $ signatures_over v)
        return v

grip k = drop 32 $ fingerprint k

smallpr k = drop 24 $ fingerprint k

-- matchpr computes the fingerprint of the given key truncated to
-- be the same lenght as the given fingerprint for comparison.
matchpr fp k = reverse $ zipWith const (reverse (fingerprint k)) fp


disjoint_fp ks = {- concatMap group2 $ -} transpose grouped
 where
    grouped    = groupBy samepr . sortBy (comparing smallpr) $ ks
    samepr a b = smallpr a == smallpr b

    {-
    -- useful for testing
    group2 :: [a] -> [[a]]
    group2 (x:y:ys) = [x,y]:group2 ys
    group2 [x]      = [[x]]
    group2 []       = []
    -}

verifyBindingsEx :: [Packet] -> ([SignatureOver], [SignatureOver]) -- ^ (binding signatures, other signatures)
verifyBindingsEx pkts = bicat . unzip $ do
        let (keys,_) = partition isKey pkts
        keys <- disjoint_fp keys
        return $ verifyBindings keys pkts
 where
    bicat (xs,ys) = (concat xs,concat ys)

getBindings ::
  [Packet]
  ->
    ( [([Packet],[SignatureOver])] -- ^ other signatures with key sets
                                   --   that were used for the verifications
    , [(Word8,
       (Packet, Packet), -- (topkey,subkey)
       [String],         -- usage flags
       [SignatureSubpacket], -- hashed data
       [Packet])] -- ^ binding signatures
    )
getBindings pkts = (sigs,bindings)
 where
    (sigs,concat->bindings) = unzip $ do
        let (keys,nonkeys) = partition isKey pkts
        keys <- disjoint_fp keys
        let (bs,sigs) = verifyBindings keys pkts
        return . ((keys,sigs),) $ do
            b <- bs -- trace ("sigs = "++show (map (map signature_issuer . signatures_over) sigs)) bs
            i <- map signature_issuer (signatures_over b)
            i <- maybeToList i
            who <- maybeToList $ find_key fingerprint (Message keys) i
            let (code,claimants) =
                    case () of
                        _ | who == topkey b -> (1,[])
                        _ | who == subkey b -> (2,[])
                        _                   -> (0,[who])
            let hashed = signatures_over b >>= hashed_subpackets
                kind = guard (code==1) >> hashed >>= maybeToList . usage
            return (code,(topkey b,subkey b), kind, hashed,claimants)

-- Returned data is simmilar to getBindings but the Word8 codes
-- are ORed together.
accBindings ::
  Bits t =>
  [(t, (Packet, Packet), [a], [a1], [a2])]
  -> [(t, (Packet, Packet), [a], [a1], [a2])]
accBindings bs = as
  where
    gs = groupBy samePair . sortBy (comparing bindingPair) $ bs
    as = map (foldl1 combine) gs
    bindingPair (_,p,_,_,_) = pub2 p
      where
        pub2 (a,b) = (pub a, pub b)
        pub a = fingerprint_material a
    samePair a b = bindingPair a == bindingPair b
    combine (ac,p,akind,ahashed,aclaimaints)
            (bc,_,bkind,bhashed,bclaimaints)
        = (ac .|. bc,p,akind++bkind,ahashed++bhashed,aclaimaints++bclaimaints)


data UserIDRecord = UserIDRecord {
    uid_full :: String,
    uid_realname :: T.Text,
    uid_user :: T.Text,
    uid_subdomain :: T.Text,
    uid_topdomain :: T.Text
}
 deriving Show

isBracket '<' = True
isBracket '>' = True
isBracket _   = False

parseUID str = UserIDRecord {
                    uid_full = str,
                    uid_realname = realname,
                    uid_user = user,
                    uid_subdomain = subdomain,
                    uid_topdomain = topdomain
                }
 where
    text = T.pack str
    (T.strip-> realname, T.dropAround isBracket-> email)
                              = T.break (=='<') text
    (user, T.tail-> hostname) = T.break (=='@') email
    ( T.reverse            -> topdomain,
      T.reverse . T.drop 1 -> subdomain)
                              = T.break (=='.') . T.reverse $ hostname


derToBase32 = map toLower . Base32.encode . S.unpack . SHA1.hashlazy

fpmatch grip key =
    (==) Nothing
         (fmap (backend (fingerprint key)) grip >>= guard . not)
 where
    backend xs ys = and $ zipWith (==) (reverse xs) (reverse ys)

listKeys pkts = listKeysFiltered [] pkts

listKeysFiltered grips pkts = do
    let (certs,bs) = getBindings pkts
        as = accBindings bs
        defaultkind (k:_) hs = k
        defaultkind []    hs = maybe "subkey"
                                     id
                                     ( listToMaybe
                                     . mapMaybe (fmap usageString . keyflags)
                                     $ hs)
        kinds = map (\(_,_,k,h,_)->defaultkind k h) as
        kindwidth = maximum $ map length kinds
        kindcol = min 20 kindwidth
        code (c,(m,s),_,_,_) = (fingerprint_material m,-c)
        ownerkey (_,(a,_),_,_,_) = a
        sameMaster (ownerkey->a) (ownerkey->b) = fingerprint_material a==fingerprint_material b
        matchgrip _ | null grips = True
        matchgrip ((code,(top,sub), kind, hashed,claimants):_) | any (flip fpmatch top . Just) grips = True
        matchgrip _ = False
        gs = filter matchgrip $ groupBy sameMaster (sortBy (comparing code) as)
    subs <- gs
    let (code,(top,sub), kind, hashed,claimants):_ = subs
        subkeys = do
            (code,(top,sub), kind, hashed,claimants) <- subs
            let ar = case code of
                        0 -> " ??? "
                        1 -> " --> "
                        2 -> " <-- "
                        3 -> " <-> "
                formkind = take kindcol $ defaultkind kind hashed ++ repeat ' '
                torhash = maybe "" id $ derToBase32 <$> derRSA sub
            concat  [ " "
                    -- , grip top
                    , (if not (null claimants)
                        then trace ("claimants: "++show (map fingerprint claimants))
                        else id) ar
                    , formkind
                    , " "
                    , fingerprint sub
                    -- , " " ++ torhash
                    , "\n" ]
                -- ++ ppShow hashed
        torkeys = do
            (code,(top,sub), kind, hashed,claimants) <- subs
            guard ("tor" `elem` kind)
            guard (code .&. 0x2 /= 0)
            maybeToList $ derToBase32 <$> derRSA sub
        uid = {- maybe "" id . listToMaybe $ -} do
            (keys,sigs) <- certs
            sig <- sigs
            guard (isCertificationSig sig)
            guard (topkey sig == top)
            let issuers = do
                    sig_over <- signatures_over sig
                    i <- maybeToList $ signature_issuer sig_over
                    maybeToList $ find_key (matchpr i) (Message keys) (reverse (take 16 (reverse i)))
                (primary,secondary) = partition (==top) issuers

            -- trace ("PRIMARY: "++show (map fingerprint primary)) $ return ()
            -- trace ("SECONDARY: "++show (map fingerprint secondary)) $ return ()
            guard (not (null primary))

            let UserIDPacket uid = user_id sig
                parsed = parseUID uid
                ar = maybe " --> " (const " <-> ") $ do
                        guard (uid_topdomain parsed == "onion" )
                        guard ( uid_realname parsed `elem` ["","Anonymous"])
                        guard (     uid_user parsed == "root" )
                        let subdom0 = L.fromChunks [encodeUtf8 (uid_subdomain parsed)]
                            len = L.length subdom0
                            subdom = Char8.unpack subdom0
                            match = ( (==subdom) . take (fromIntegral len))
                        guard (len >= 16)
                        listToMaybe $ filter match torkeys
            unlines $ [ " " ++ ar ++ "@" ++ " " ++ uid_full parsed ]
                    ++ map (\k -> "      " ++ "^ signed: " ++ fingerprint k) secondary
        (_,sigs) = unzip certs
    "master-key " ++ fingerprint top ++ "\n" ++ uid ++"  ...\n" ++ subkeys ++ "\n"


data PGPKeyFlags =
    Special
    | Vouch -- Signkey
    | Sign
    | VouchSign
    | Communication
    | VouchCommunication
    | SignCommunication
    | VouchSignCommunication
    | Storage
    | VouchStorage
    | SignStorage
    | VouchSignStorage
    | Encrypt
    | VouchEncrypt
    | SignEncrypt
    | VouchSignEncrypt
 deriving (Eq,Show,Read,Enum)

usageString flgs =
 case flgs of
    Special -> "special"
    Vouch -> "vouch" -- signkey
    Sign -> "sign"
    VouchSign -> "vouch-sign"
    Communication -> "communication"
    VouchCommunication -> "vouch-communication"
    SignCommunication -> "sign-communication"
    VouchSignCommunication -> "vouch-sign-communication"
    Storage -> "storage"
    VouchStorage -> "vouch-storage"
    SignStorage -> "sign-storage"
    VouchSignStorage -> "vouch-sign-storage"
    Encrypt -> "encrypt"
    VouchEncrypt -> "vouch-encrypt"
    SignEncrypt -> "sign-encrypt"
    VouchSignEncrypt -> "vouch-sign-encrypt"


keyflags flgs@(KeyFlagsPacket {}) =
    Just . toEnum $
        (   bit 0x1 certify_keys
        .|. bit 0x2 sign_data
        .|. bit 0x4 encrypt_communication
        .|. bit 0x8 encrypt_storage )     :: Maybe PGPKeyFlags
    -- other flags:
    --  split_key
    --  authentication (ssh-client)
    --  group_key
 where
    bit v f = if f flgs then v else 0
keyflags _ = Nothing


modifyUID (UserIDPacket str) = UserIDPacket str'
 where
    (fstname,rst) = break (==' ') str
    str' = mod fstname ++ rst
    mod "Bob" = "Bob Fucking"
    mod x     = x
modifyUID other              = other

todo = error "unimplemented"

-- TODO: switch to System.Environment.lookupEnv
--       when linking against newer base libraries.
lookupEnv var =
    handleIO_ (return Nothing) $ fmap Just (getEnv var)

unmaybe def = fmap (maybe def id)

expandPath path (c:cs) | c/='/'    = path ++ "/" ++ (c:cs)
                       | otherwise = c:cs
expandPath path []                 = []


readPacketsFromFile :: FilePath -> IO Message
readPacketsFromFile fname = do
    input <- L.readFile fname
    return $
      case decodeOrFail input of
        Right (_,_,msg ) -> msg
        Left  (_,_,_)    -> Message []

lockFiles fs = do
    let dolock f = do
            lk <- dotlock_create f 0
            let fail = return Nothing
                dotake lk = do
                    e <- dotlock_take lk (-1)
                    if e==0 then return (Just lk)
                            else fail
            v <- maybe fail dotake lk
            return (v,f)
    ls <- mapM dolock fs
    let (lks, fails) = partition (isJust . fst) ls
    return (map (\(lk,f)->(fromJust lk,f)) lks, map snd fails)

unlockFiles lks = forM_ lks $ \lk -> dotlock_release lk

parseOptionFile fname = do
    xs <- fmap lines (readFile fname)
    let ys = filter notComment xs
        notComment ('#':_) = False
        notComment cs      = not (all isSpace cs)
    return ys

{-
options_from_file ::
        (forall a. [String] -> Term a -> IO (Either EvalExit a))
        -> Term b
        -> (String,String,Term (Maybe String))
        -> ([String],Term (Maybe String))
        -> IO [String]
options_from_file unwrapCmd term (homevar,appdir,home) (optfile_alts,options_file) = doit
 where
    homedir = envhomedir <$> home
    envhomedir opt = do
        gnupghome <- lookupEnv homevar >>=
                  \d -> return $ d >>= guard . (/="") >> d
        home <- flip fmap getHomeDirectory $
                  \d -> fmap (const d) $ guard (d/="")
        let homegnupg = (++('/':appdir)) <$> home
        let val = (opt `mplus` gnupghome `mplus` homegnupg)
        return $ val

    doit = do
        args <- getArgs
        {-
        let wants_help =
                not . null $ filter cryForHelp args
                        where cryForHelp "--help"    = True
                              cryForHelp "--version" = True
                              cryForHelp x =
                                and (zipWith (==) x "--help=")
        -}
        (o,h) <- do
            val <- unwrapCmd args (liftA2 (,) options_file homedir)
            case val of
                Left e -> return (Nothing,Nothing)
                Right (o,h)    -> (o,) <$> h
        ofile <- fmap listToMaybe . flip (maybe (return [])) h $ \h ->
                let optfiles = map (second ((h++"/")++))
                                   (maybe optfile_alts' (:[]) o')
                    optfile_alts' = zip (False:repeat True) optfile_alts
                    o' = fmap (False,) o
                in filterM (doesFileExist . snd) optfiles
        args <- flip (maybe $ return args) ofile $ \(forgive,fname) -> do
            let h' = fromJust h
            newargs <- (:) <$> pure ("homedir "++h') <*> parseOptionFile fname
            let toArgs = toHead ("--"++) . words
                toHead f (x:xs) = f x : xs
                toHead f []     = []
                voidTerm = fmap (const ())
                appendArgs as [] = return as
                appendArgs as (configline:cs) = do
                    let xs = toArgs configline
                    w <-unwrap (xs++as) (voidTerm term,defTI)
                    case w of
                        Left  _ -> appendArgs as cs
                        Right _ -> appendArgs (xs++as) cs
            -- TODO: check errors if forgive = False
            appendArgs args newargs
        return args

runWithOptionsFile :: (Term (IO b), TermInfo) -> IO b
runWithOptionsFile (term,ti) = do
    as <- options_from_file unwrapCmd
                            term
                            ("GNUPGHOME",".gnupg",opt_homedir)
                            (["keys.conf","gpg.conf-2","gpg.conf"]
                            ,opt_options)
    q <- eval as (term , ti)
    q
 where
    unwrapCmd args term = unwrap args (term,defTI)

runChoiceWithOptionsFile ::
  (Term (IO b), TermInfo) -> [(Term (IO b), TermInfo)] -> IO b
runChoiceWithOptionsFile (realterm,ti) choices = do
    as <- options_from_file unwrapCmd
                            realterm
                            ("GNUPGHOME",".gnupg",opt_homedir)
                            (["keys.conf","gpg.conf-2","gpg.conf"]
                            ,opt_options)
    -- putStrLn $ "as = " ++ show as
    q <- evalChoice as (realterm , ti) choices
    q
 where
    unwrapCmd args t =
        unwrapChoice args (realterm <:> t,ti) (map (neuter t) choices)
    neuter term (t,ti) = (t <:> term, ti)

data Command =
    List
    | Autosign
 deriving (Eq,Show,Read,Enum)

capitolizeFirstLetter (x:xs) = toUpper x : xs
capitolizeFirstLetter xs     = xs

instance ArgVal Command where
    converter =
      ( maybe (Left $ text "unknown command") Right
        . fmap fst . listToMaybe . reads
        . capitolizeFirstLetter . map toLower
      , text . map toLower . show
      )
class AutoMaybe a
instance AutoMaybe Command
instance (ArgVal a, AutoMaybe a) => ArgVal (Maybe a) where
    converter =
      ( toRight Just . fst converter
      , maybe (text "(unspecified)") id . fmap (snd converter)
      )

toRight f (Right x) = Right (f x)
toRight f (Left y)  = Left  y

cmd :: Term Command
cmd = required . pos 0 Nothing $ posInfo
  { posName = "command"
  , posDoc  = "What action to perform."
  }

a <:> b = flip const <$> a <*> b
infixr 2 <:>

selectAction cmd actions = actions !! fromEnum cmd

cmdInfo :: ArgVal cmd =>
    cmd -> String -> Term a -> (cmd, (Term a, TermInfo))
cmdInfo cmd doc action =
    ( cmd
    , ( action
      , defTI { termName = print cmd
              , termDoc  = doc } ) )
  where
    print = show . snd converter

cmdlist :: (Command, (Term (IO ()), TermInfo))
cmdlist = cmdInfo List "list key pairs for which secrets are known" $
    (>>= putStrLn . listKeys . unMessage) <$> secret_packets
 where unMessage (Message pkts) = pkts

cmdautosign = cmdInfo Autosign "auto-sign tor-style uids" $
    pure (putStrLn "autosign")


multiCommand ::
  TermInfo
  -> [(Command, (Term a, TermInfo))]
  -> ( (Term a, TermInfo)
     , [(Term a, TermInfo)] )
multiCommand ti choices =
    ( ( selectAction <$> cmd <*> sequenceA (map strip choices)
      , ti )
    , map snd choices )
 where
    selectAction cmd choices =
        fromJust $ lookup (cmd::Command) choices
    strip (cmd,(action,_)) = fmap (cmd,) action
-}


trimCR bs = fst $ S.spanEnd (\x -> x==10 || x==13) bs

guessKeyFormat 'P' "ssh-client" = "SSH"
guessKeyFormat 'S' "ssh-client" = "PEM"
guessKeyFormat 'S' "ssh-host"   = "PEM"
guessKeyFormat _   _            = "PEM" -- "PGP"

readKeyFromFile False "PEM" fname = do
    timestamp <- modificationTime <$> getFileStatus fname
    input <- L.readFile fname
    let dta = extractPEM "RSA PRIVATE KEY" input
    -- Char8.putStrLn $ "dta = " <> dta
    let rsa = do
           e <- decodeASN1 DER . L.pack <$> Base64.decode (Char8.unpack dta)
           asn1 <- either (const Nothing) Just e
           k <- either (const Nothing) (Just . fst) (fromASN1 asn1)
           let _ = k :: RSAPrivateKey
           return k
    -- putStrLn $ "rsa = "++ show rsa
    return . Message $ do
        rsa <- maybeToList rsa
        return $ SecretKeyPacket
            { version = 4
            , timestamp = toEnum (fromEnum timestamp)
            , key_algorithm = RSA
            , key = [ -- public fields...
                     ('n',rsaN rsa)
                    ,('e',rsaE rsa)
                    -- secret fields
                    ,('d',rsaD rsa)
                    ,('p',rsaQ rsa) -- Note: p & q swapped
                    ,('q',rsaP rsa) -- Note: p & q swapped
                    ,('u',rsaCoefficient rsa)
                    ]
            , s2k_useage = 0
            , s2k = S2K 100 ""
            , symmetric_algorithm = Unencrypted
            , encrypted_data = ""
            , is_subkey = True
            }
readKeyFromFile is_public fmt filename = error ("unimplemented key type: "++fmt)

getPassphrase cmd =
         case passphrase_fd cmd of
                Just fd -> do pwh <- fdToHandle (toEnum fd)
                              fmap trimCR $ S.hGetContents pwh
                Nothing -> return ""


#define HOMEOPTION (def &= explicit &= name "homedir" &= typDir )

data KeySpec =
      KeyGrip String
    | KeyTag Packet String
    | KeyUidMatch String


is40digitHex xs = ys == xs && length ys==40
  where
    ys = filter ishex xs
    ishex c | '0' <= c && c <= '9' = True
            | 'A' <= c && c <= 'F' = True
            | 'a' <= c && c <= 'f' = True
    ishex c = False

scanPackets :: FilePath -> [Packet] -> [(Packet,Packet,(Packet,Map.Map FilePath Packet))]
scanPackets filename [] = []
scanPackets filename (p:ps) = scanl doit (doit (MarkerPacket,MarkerPacket,ret MarkerPacket) p) ps
 where
    ret p = (p,Map.empty)
    doit (top,sub,prev) p =
        case p of
            _ | isKey p && not (is_subkey p) -> (p,MarkerPacket,ret p)
            _ | isKey p && is_subkey p       -> (top,p,ret p)
            _ | isUserID p                   -> (top,p,ret p)
            _ | isTrust p                    -> (top,sub,updateTrust top sub prev p)
            _ | otherwise                    -> (top,sub,ret p)

    updateTrust top (PublicKeyPacket {}) (pre,t) p = (pre,Map.insert filename p t) -- public
    updateTrust (PublicKeyPacket {}) _   (pre,t) p = (pre,Map.insert filename p t) -- public
    updateTrust _                    _   (pre,t) p = (pre,Map.insert filename p t) -- secret


data OriginFlags = OriginFlags {
        originallyPublic :: Bool,
        originalNum :: Int
    }
    deriving Show
origin :: Packet -> Int -> OriginFlags
origin p n = OriginFlags ispub n
 where
    ispub = case p of
                    SecretKeyPacket {} -> False
                    _                  -> True

type OriginMap = Map.Map FilePath OriginFlags
data MappedPacket = MappedPacket
        { packet :: Packet
        , locations :: OriginMap
        }

type TrustMap = Map.Map FilePath Packet
type SigAndTrust = ( MappedPacket
                   , TrustMap     ) -- trust packets

type KeyKey = [Char8.ByteString]
data SubKey = SubKey MappedPacket [SigAndTrust]
data KeyData = KeyData MappedPacket    -- main key
                       [SigAndTrust]  -- sigs on main key
                       ((Map.Map String [SigAndTrust]),OriginMap)  -- uids
                       (Map.Map KeyKey SubKey)    -- subkeys

type KeyDB = Map.Map KeyKey KeyData

keykey key = fingerprint_material key -- TODO: smaller key?
uidkey (UserIDPacket str) = str

-- Compare master keys, LT is prefered for merging
keycomp (SecretKeyPacket {}) (PublicKeyPacket {}) = LT
keycomp (PublicKeyPacket {}) (SecretKeyPacket {}) = GT
keycomp a b | a==b = EQ
keycomp a b = error $ unlines ["Unable to merge keys:"
                              , fingerprint a
                              , PP.ppShow a
                              , fingerprint b
                              , PP.ppShow b
                              ]

-- Compare subkeys, LT is prefered for merging
subcomp (SecretKeyPacket {}) (PublicKeyPacket {}) = LT
subcomp (PublicKeyPacket {}) (SecretKeyPacket {}) = GT
subcomp a b | a==b = EQ
subcomp a b = error $ unlines ["Unable to merge subs:"
                              , fingerprint a
                              , PP.ppShow a
                              , fingerprint b
                              , PP.ppShow b
                              ]
subcomp_m a b = subcomp (packet a) (packet b)

merge :: KeyDB -> FilePath -> Message -> KeyDB
merge db filename (Message ps) = foldl mergeit db (zip [0..] qs)
 where
    qs = scanPackets filename ps
    asMapped n p = MappedPacket p (Map.singleton filename (origin p n))
    asSigAndTrust n (p,tm) = (asMapped n p,tm)
    emptyUids = (Map.empty,Map.empty)
    -- mergeit db (_,_,TrustPacket {}) = db -- Filter TrustPackets
    mergeit :: KeyDB -> (Int,(Packet,Packet,(Packet,Map.Map FilePath Packet))) -> KeyDB
    mergeit db (n,(top,sub,ptt@(p,trustmap))) | isKey top = Map.alter update (keykey top) db
     where
        -- NOTE:
        --  if a keyring file has both a public key packet and a secret key packet
        --  for the same key, then only one of them will survive, which ever is 
        --  later in the file.
        -- 
        --  This is due to the use of statements like 
        --      (Map.insert filename (origin p n) (locations key))
        --
        update v | isKey p && not (is_subkey p)
          = case v of
             Nothing -> Just $ KeyData (asMapped n p) [] emptyUids Map.empty
             Just (KeyData key sigs uids subkeys) | keykey (packet key) == keykey p
                     -> Just $ KeyData ( MappedPacket (minimumBy keycomp [packet key,p])
                                                      (Map.insert filename (origin p n) (locations key)) )
                                       sigs
                                       uids
                                       subkeys
             _       -> error . concat $ ["Unexpected master key merge error: "
                                         ,show (fingerprint top, fingerprint p)]
        update (Just (KeyData key sigs uids subkeys)) | isKey p && is_subkey p
          = Just $ KeyData key sigs uids (Map.alter (mergeSubkey n p) (keykey p) subkeys)
        update (Just (KeyData key sigs (uids,locs) subkeys)) | isUserID p
          = Just $ KeyData key sigs ( Map.alter (mergeUid ptt) (uidkey p) uids
                                    , Map.insert filename (origin p n) locs )
                                    subkeys
        update (Just (KeyData key sigs uids subkeys))
          = case sub of
             MarkerPacket    -> Just $ KeyData key (mergeSig n ptt sigs) uids subkeys
             UserIDPacket {} -> Just $ KeyData key
                                               sigs
                                               (Map.alter (mergeUidSig n ptt) (uidkey sub) (fst uids)
                                               ,Map.insert filename (origin p n) (snd uids))
                                               subkeys
             _  | isKey sub  -> Just $ KeyData key
                                               sigs
                                               uids
                                               (Map.alter (mergeSubSig n ptt) (keykey sub) subkeys)
             _ -> error $ "Unexpected PGP packet 1: "++(words (show p) >>= take 1)
        update _ = error $ "Unexpected PGP packet 2: "++(words (show p) >>= take 1)

    mergeit _  (_,(_,_,p)) = error $ "Unexpected PGP packet 3: "++whatP p

    mergeSubkey :: Int -> Packet -> Maybe SubKey -> Maybe SubKey
    mergeSubkey n p Nothing                  = Just $ SubKey (asMapped n p) []
    mergeSubkey n p (Just (SubKey key sigs)) = Just $
        SubKey (MappedPacket (minimumBy subcomp [packet key,p])
                             (Map.insert filename (origin p n) (locations key)))
               sigs

    mergeUid (UserIDPacket s,_) Nothing     = Just []
    mergeUid (UserIDPacket s,_) (Just sigs) = Just sigs
    mergeUid p _ = error $ "Unable to merge into UID record: " ++whatP p

    whatP (a,_) = concat . take 1 . words . show $ a


    mergeSig :: Int -> (Packet,TrustMap) -> [SigAndTrust] -> [SigAndTrust]
    mergeSig n sig sigs =
      let (xs,ys) = break (isSameSig sig) sigs
          first f (x,y) = (f x,y)
      in if null ys
          then sigs++[first (asMapped n) sig]
          else let y:ys'=ys
               in xs ++ (mergeSameSig n sig y : ys')


    isSameSig (a,_) (MappedPacket b _,_) | isSignaturePacket a && isSignaturePacket b =
        a { unhashed_subpackets=[] } == b { unhashed_subpackets = [] }
    isSameSig (a,_) (MappedPacket b _,_) = a==b

    mergeSameSig :: Int -> (Packet,TrustMap) -> (MappedPacket,TrustMap) -> (MappedPacket, TrustMap)
    mergeSameSig n (a,ta) (MappedPacket b locs,tb) | isSignaturePacket a && isSignaturePacket b =
       ( MappedPacket (b { unhashed_subpackets =
                            foldl mergeItem (unhashed_subpackets b) (unhashed_subpackets a) })
                      (Map.insert filename (origin a n) locs)
        , tb `Map.union` ta )

     where
        -- TODO: when merging items, we should delete invalidated origins
        -- from the orgin map.
        mergeItem ys x = if x `elem` ys then ys else ys++[x]

    mergeSameSig n a b = trace ("discarding dup "++show a) b

    mergeUidSig n sig (Just sigs) = Just $ mergeSig n sig sigs
    mergeUidSig n sig Nothing = Just [asSigAndTrust n sig]

    mergeSubSig n sig (Just (SubKey key sigs)) = Just $ SubKey key (mergeSig n sig sigs)
    mergeSubSig n sig Nothing = error $
        "Unable to merge subkey signature: "++(words (show sig) >>= take 1)

flattenKeys :: Bool -> KeyDB -> Message
flattenKeys isPublic db = Message $ concatMap (map packet . flattenTop "" isPublic . snd) (prefilter . Map.assocs $ db)
 where
    prefilter = if isPublic then id else filter isSecret
                 where
                  isSecret (_,(KeyData
                                  (MappedPacket { packet=(SecretKeyPacket {})})
                                  _
                                  _
                                  _)) = True
                  isSecret _          = False


concatSort fname getp f = concat . sortByHint fname getp . map f

flattenTop :: FilePath -> Bool -> KeyData -> [MappedPacket]
flattenTop fname ispub (KeyData key sigs uids subkeys) =
    unk ispub key : 
            ( concatSort fname head (flattenUid fname ispub (snd uids)) (Map.assocs (fst uids))
             ++ concatSort fname head (flattenSub fname ispub) (Map.elems subkeys))

flattenUid :: FilePath -> Bool -> OriginMap -> (String,[SigAndTrust]) -> [MappedPacket]
flattenUid fname ispub om (str,sigs) = 
    MappedPacket (UserIDPacket str) om : concatSort fname head (unsig fname ispub) sigs

flattenSub :: FilePath -> Bool -> SubKey -> [MappedPacket]
flattenSub fname ispub (SubKey key sigs) = unk ispub key: concatSort fname head (unsig fname ispub) sigs

unk :: Bool -> MappedPacket -> MappedPacket
unk isPublic = if isPublic then toPacket secretToPublic else id
                where toPacket f (MappedPacket p m) = MappedPacket (f p) m

unsig :: FilePath -> Bool -> SigAndTrust -> [MappedPacket]
unsig fname isPublic (sig,trustmap) = 
    [sig]++ map (asMapped (-1)) ( take 1 . Map.elems $ Map.filterWithKey f trustmap)
  where
    f n _ = n==fname -- && trace ("fname=n="++show n) True
    asMapped n p = MappedPacket p (Map.singleton fname (origin p n))

ifSecret (SecretKeyPacket {}) t f = t
ifSecret _                    t f = f

showPacket :: Packet -> String
showPacket p | isKey p   = (if is_subkey p 
                              then showPacket0 p
                              else ifSecret p "----Secret-----" "----Public-----")
                           ++ " "++ fingerprint p
             | isUserID p = showPacket0 p ++ " " ++ show (uidkey p)
             | otherwise = showPacket0 p
showPacket0 p = concat . take 1 $ words (show p)

sortByHint fname f = sortBy (comparing gethint)
  where
    gethint = maybe defnum originalNum . Map.lookup fname . locations . f
    defnum = -1

keyPacket (KeyData k _ _ _) = k

writeOutKeyrings db = do
    let ks = Map.elems db
        fs = Map.keys (foldr unionfiles Map.empty ks)
                where unionfiles (KeyData p _ _ _) m =
                        Map.union m (locations p)
        fromfile f (KeyData p _ _ _) = Map.member f $ locations p
    let s = do
        f <- fs
        let x = do
                d@(KeyData p _ _ _) <- filter (fromfile f) (sortByHint f keyPacket ks)
                n <- maybeToList $ Map.lookup f (locations p)
                flattenTop f (originallyPublic n) d
            changes = filter notnew x
                where notnew p = isNothing (Map.lookup f $ locations p)
        unlines $ ( (f ++ ":") : map (showPacket . packet) x) ++
                  ( "CHANGES: " : map (("  "++) . showPacket . packet) changes)
    putStrLn s
    -- putStrLn $ "fs = " ++ show fs 
    return () -- TODO

data Arguments =
        Cross_Merge { homedir :: Maybe FilePath
                    , passphrase_fd :: Maybe Int
                    , files :: [FilePath]
                    }
  deriving (Show, Data, Typeable)



main = do
    dotlock_init
    args <- cmdArgs $ modes
        [ Cross_Merge HOMEOPTION
              (def &= opt ("passphrase"::String)
                &= typ "FD"
                &= (help . concat)  ["file descriptor from "
                                    ,"which to read passphrase"])
              (def &= args &= typFile)
            &= help "Merge multiple secret keyrings to stdout."
        ]
        &= program "kiki"
        &= summary "kiki - a pgp key editing utility"
    doCmd args
 where
    envhomedir opt = do
        gnupghome <- lookupEnv homevar >>=
                  \d -> return $ d >>= guard . (/="") >> d
        home <- flip fmap getHomeDirectory $
                  \d -> fmap (const d) $ guard (d/="")
        let homegnupg = (++('/':appdir)) <$> home
        let val = (opt `mplus` gnupghome `mplus` homegnupg)
        return $ val

    homevar = "GNUPGHOME"
    appdir  = ".gnupg"
    optfile_alts = ["keys.conf","gpg.conf-2","gpg.conf"]

    getHomeDir cmd = do
        homedir <- envhomedir (homedir cmd)
        flip (maybe (error "Could not determine home directory."))
             homedir $ \homedir -> do
        -- putStrLn $ "homedir = " ++show homedir
        let secring = homedir ++ "/" ++ "secring.gpg"
            pubring = homedir ++ "/" ++ "pubring.gpg"
        -- putStrLn $ "secring = " ++ show secring
        workingkey <- getWorkingKey homedir
        return (homedir,secring,pubring,workingkey)

    getWorkingKey homedir = do
        let o = Nothing
            h = Just homedir
            args = ["hi"]
        ofile <- fmap listToMaybe . flip (maybe (return [])) h $ \h ->
                let optfiles = map (second ((h++"/")++))
                                   (maybe optfile_alts' (:[]) o')
                    optfile_alts' = zip (False:repeat True) optfile_alts
                    o' = fmap (False,) o
                in filterM (doesFileExist . snd) optfiles
        args <- flip (maybe $ return []) ofile $
            \(forgive,fname) -> parseOptionFile fname
        let config = map (topair . words) args
                        where topair (x:xs) = (x,xs)
        return $ lookup "default-key" config >>= listToMaybe

    getPGPEnviron cmd = do
        (homedir,secring,pubring,grip) <- getHomeDir cmd
        (Message sec) <- readPacketsFromFile secring
        let (keys,_) = partition (\k -> case k of
                                   { SecretKeyPacket {} -> True
                                   ; _                  -> False })
                                 sec
        return (homedir,sec, grip `mplus` fmap fingerprint (listToMaybe keys))

    getTorKeys pub = do
        xs <- groupBindings pub
        (_,(top,sub),us,_,_) <- xs
        guard ("tor" `elem` us)
        let torhash = maybe "" id $ derToBase32 <$> derRSA sub
        return (top,(torhash,sub))

    uidScan pub = scanl (\(mkey,u) w ->
                             case () of
                              _ | isPublicMaster w -> (w,u)
                              _ | isUserID w -> (mkey,w)
                              _ | otherwise  -> (mkey,u)
                            )
                          (w0,w0)
                          ws
                        where
                            w0:ws = pub

    signSelfAuthTorKeys selfkey g sec grip timestamp xs = ys
     where
        keys = filter isKey sec
        mainpubkey = fst (head xs)
        uid:xs' = map snd xs
        (sigs, xs'') = span isSignaturePacket xs'
        overs sig = signatures $ Message (keys++[uid,sig])
        vs :: [ ( Packet -- signature
                , Maybe SignatureOver) -- Nothing means non-verified
              ]
        vs = do
            sig <- sigs
            let vs = overs sig >>= return . verify (Message keys)
                ws = filter (not . null . signatures_over) vs
                ws' = if null ws then [Nothing] else map Just ws
            v <- ws'
            return (sig,v)
        selfsigs = filter (\(sig,v) -> fmap topkey v == selfkey) vs
        has_self = not . null $ selfsigs
        sigs' = if has_self
                    then sigs
                    {-
                    else trace ( "key params: "++params (fromJust selfkey)++"\n"
                                ++traceSig (topkey new_sig)
                                           (user_id new_sig)
                                           (signatures_over new_sig))
                               sigs
                            ++ {- map modsig -} (signatures_over new_sig)
                    -}
                    else sigs ++ signatures_over new_sig
        modsig sig = sig { signature = map id (signature sig) }
            where plus1 (MPI x) = MPI (x+1)
        params newtop = public ++ map fst (key newtop) ++ "}"
                where
                    public = case newtop of
                                PublicKeyPacket {} -> "public{"
                                SecretKeyPacket {} -> if L.null (encrypted_data newtop )
                                                            then "secret{"
                                                            else "encrypted{"
                                _                  -> "??????{"
        traceSig newtop newuid new_sig = (unlines ["mainpubkey:"++ show (fingerprint mainpubkey)
                                        ,"new_sig topkey:"++ (show . fingerprint $ newtop)
                                        ,"new_sig topkey params: "++ params newtop
                                        ,"new_sig user_id:"++ (show newuid)
                                        ,"new_sig |over| = " ++ (show . length $ new_sig)
                                        ,"new_sig hashed = " ++ (PP.ppShow . concatMap hashed_subpackets $ new_sig)
                                        ,"new_sig unhashed = " ++ (show . concatMap unhashed_subpackets $ new_sig)
                                        ,"new_sig type: " ++ (show . map signature_type $ new_sig)
                                        ,"new_sig signature:" ++ (show . concatMap signature $ new_sig)
                                        ,"new_sig isSignaturePacket(over) = " ++ (show . map isSignaturePacket $ new_sig)
                                        ,"issuer = " ++ show (map signature_issuer new_sig)
                                        ])
        flgs = if keykey mainpubkey == keykey (fromJust selfkey)
                then keyFlags0 mainpubkey (map fst selfsigs)
                else []
        new_sig = fst $ torsig g mainpubkey (fromJust selfkey) uid timestamp flgs

        ys = uid:sigs'++xs''

    {-
    doCmd cmd@(List {}) = do
        (homedir,secring,grip) <- getHomeDir cmd
        (Message sec) <- readPacketsFromFile secring
        putStrLn $ listKeys sec

    doCmd cmd@(WorkingKey {}) = do
        (homedir,secring,grip) <- getHomeDir cmd
        (Message sec) <- readPacketsFromFile secring
        -- let s2k' = map s2k (filter isKey sec)
        -- putStrLn $ "s2k = " ++ show s2k'
        putStrLn $ listKeysFiltered (maybeToList grip) sec
        return ()

    doCmd cmd@(AutoSign {}) = do
        ( homedir -- e3ozbhvej4jvlu43.onion/gpg/gnupghome
          , sec   -- e3ozbhvej4jvlu43.onion/gpg/gnupghome/secring.gpg
          , grip  -- Just "AD1CA892FCF4ED9829C762269BDEA5B4D5643321"
          ) <- getPGPEnviron cmd
        flip (maybe (error "No working key?")) grip $ \grip -> do
        pw <- getPassphrase cmd
        let (pre, wk:subs) = seek_key (KeyGrip grip) sec
            wkun = if symmetric_algorithm wk == Unencrypted
                    then Just wk
                    else do
                        k <- decryptSecretKey pw wk
                        guard (symmetric_algorithm k == Unencrypted)
                        return k
        flip (maybe (error "Bad passphrase?")) wkun$ \wkun -> do
        -- putStrLn $ "getPGPEnviron -> " ++ show (homedir,length sec,grip)
        (Message pub) <- readPacketsFromFile (input cmd)
        putStrLn $ listKeys pub
        -- forM_ (zip [1..] pub) $ \(i,k) -> do
        --     putStrLn $ show i ++ ": " ++ show k
        let torbindings = getTorKeys pub
            keyed = uidScan pub
            marked = zipWith doit keyed pub
            doit (mkey,u) packet = (isTorID packet, (mkey,u,packet))
                where
                    isTorID (UserIDPacket str) =
                        and [ uid_topdomain parsed == "onion"
                            , uid_realname parsed `elem` ["","Anonymous"]
                            , uid_user parsed == "root"
                            , fmap (match . fst) (lookup mkey torbindings)
                                == Just True ]
                      where parsed = parseUID str
                            match = ( (==subdom) . take (fromIntegral len))
                            subdom0 = L.fromChunks [encodeUtf8 (uid_subdomain parsed)]
                            subdom = Char8.unpack subdom0
                            len = T.length (uid_subdomain parsed)

                    isTorID _                  = False

        g <- newGenIO
        timestamp <- now
        -- timestamp <- epochTime
        let xs:xss = groupBy (\_ (b,_)->not b) marked
            pub' = map (snd . cleanup) xs
                    ++ concatMap (signSelfAuthTorKeys (Just wkun) (g::SystemRandom) sec grip timestamp)
                                 (map (map cleanup) xss)
            cleanup (_,(topkey,_,pkt)) = (topkey,pkt)
        putStrLn $ "-------- signed ------> " -- ++ show (length pub, length pub')
        putStrLn ""
        putStrLn $ listKeysFiltered (map fingerprint (filter isPublicMaster pub'))  (sec++pub')

        let signed_bs = encode (Message pub')
        L.writeFile (output cmd) signed_bs

    doCmd cmd@(Public {}) = do
        ( homedir -- e3ozbhvej4jvlu43.onion/gpg/gnupghome
          , sec   -- e3ozbhvej4jvlu43.onion/gpg/gnupghome/secring.gpg
          , grip  -- Just "AD1CA892FCF4ED9829C762269BDEA5B4D5643321"
          ) <- getPGPEnviron cmd
        let pub = map secretToPublic sec
            bs = encode (Message pub)
        L.writeFile (output cmd) bs

    doCmd cmd@(DumpPackets {}) = do
        ( homedir -- e3ozbhvej4jvlu43.onion/gpg/gnupghome
          , sec   -- e3ozbhvej4jvlu43.onion/gpg/gnupghome/secring.gpg
          , grip  -- Just "AD1CA892FCF4ED9829C762269BDEA5B4D5643321"
          ) <- getPGPEnviron cmd
        p <- case files cmd of
                    [] -> return sec
                    fs -> do
                            ms <- mapM readPacketsFromFile fs
                            let unwrap (Message ps) = ps
                            return (concatMap unwrap ms)
        if map toLower (marshal_test cmd) `elem` ["y","yes"]
            then L.putStr $ encode (Message p)
            else putStrLn $ PP.ppShow p

    doCmd cmd@(MergeSecrets {}) = do
        ( homedir -- e3ozbhvej4jvlu43.onion/gpg/gnupghome
          , sec   -- e3ozbhvej4jvlu43.onion/gpg/gnupghome/secring.gpg
          , grip  -- Just "AD1CA892FCF4ED9829C762269BDEA5B4D5643321"
          ) <- getPGPEnviron cmd
        let db = merge Map.empty "%secring" (Message sec)
        ms <- mapM readPacketsFromFile' (files cmd)
        let db' = foldl' (uncurry . merge) db ms
            m = flattenKeys False db'
        L.putStr (encode m)
        return ()

    -}

    doCmd cmd@(Cross_Merge {}) = do
        (homedir,secring,pubring,grip0) <- getHomeDir cmd
        -- grip0 may be empty, in which case we should use the first key
        (fsns,failed_locks) <- lockFiles (secring:pubring:files cmd)
        forM_ failed_locks $ \f -> warn $ "Failed to lock: " ++ f
        let (lks,fs) = unzip fsns
        forM_ fs $ \f -> warn $ "locked: " ++ f
        let readp n = fmap (n,) (readPacketsFromFile n)
        ms <- mapM readp fs
        let db = foldl' (uncurry . merge) Map.empty ms
        writeOutKeyrings db
        unlockFiles lks
        return ()

    {-
    doCmd cmd@(CatPub {}) = do
        let spec:files = catpub_args cmd
        let (topspec,subspec) = unprefix '/' spec
            (toptyp,top) = unprefix ':' topspec
            (subtyp,sub) = unprefix ':' subspec

        {-
        putStrLn $ "files = " ++ show files
        putStrLn $ "topspec = " ++show (toptyp,top)
        putStrLn $ "subspec = " ++show (subtyp,sub)
        -}
        ( homedir -- e3ozbhvej4jvlu43.onion/gpg/gnupghome
          , sec   -- e3ozbhvej4jvlu43.onion/gpg/gnupghome/secring.gpg
          , grip  -- Just "AD1CA892FCF4ED9829C762269BDEA5B4D5643321"
          ) <- getPGPEnviron cmd

        flip (maybe (error "No working key?")) grip $ \grip -> do

        ms <- mapM readPacketsFromFile' files
        let db = merge Map.empty "%secring" (Message sec)
            db' = foldl' (uncurry . merge) db ms
            m = flattenKeys True db'
            Message allpkts = m

        let topspec = case () of
                        _ | null top && (subtyp=="fp" || (null subtyp && is40digitHex sub))
                                     -> KeyGrip sub
                        _ | null top -> KeyGrip grip
                        _ | toptyp=="fp" || (null toptyp && is40digitHex top)
                                     -> {- trace "using top" $ -} KeyGrip top
                        _ | toptyp=="u" -> KeyUidMatch top
                        _ | otherwise -> KeyUidMatch top
            (pre, wksubs) = seek_key topspec allpkts
        if null wksubs then error ("No match for "++spec) else do
        let wk:subs = wksubs
            (_,wksubs') = seek_key topspec subs -- ambiguity check
            (_,ys) = case subtyp of
                        "t" -> seek_key (KeyTag wk sub) subs
                        "fp" | top=="" -> ([],wk:subs)
                        "" | top=="" && is40digitHex sub -> ([],wk:subs)
                        "" -> seek_key (KeyTag wk sub) subs
        when (not (null ys)) $ do
        let (_,ys') = seek_key (KeyTag wk sub) (tail ys) -- ambiguity check
            k = head ys
            rsa = pkcs8 . fromJust $ rsaKeyFromPacket k
            der = encodeASN1 DER (toASN1 rsa [])
            qq  = Base64.encode (L.unpack der)
            split64 [] = []
            split64 qq = as : split64 bs where (as,bs) = splitAt 64 qq
        -- putStrLn $ "top = " ++ show top
        -- putStrLn $ "wk = " ++ fingerprint wk
        -- putStrLn $ fingerprint k
        {-
        putStrLn $ show rsa
        putStrLn $ show der
        -}
        if null ys' && null wksubs'
         then
            putStr $ unlines (["-----BEGIN PUBLIC KEY-----"]
                              ++split64 qq
                              ++["-----END PUBLIC KEY-----"])
         else
            error "Key specification is ambiguous."

    doCmd cmd@(Add {}) = do
        ( homedir -- e3ozbhvej4jvlu43.onion/gpg/gnupghome
          , sec   -- e3ozbhvej4jvlu43.onion/gpg/gnupghome/secring.gpg
          , grip  -- Just "AD1CA892FCF4ED9829C762269BDEA5B4D5643321"
          ) <- getPGPEnviron cmd
        pw <- getPassphrase cmd

        flip (maybe (error "No working key?")) grip $ \grip -> do

        let (pre, wk:subs) = seek_key (KeyGrip grip) sec
            wkun = if symmetric_algorithm wk == Unencrypted
                    then Just wk
                    else do
                        k <- decryptSecretKey pw wk
                        guard (symmetric_algorithm k == Unencrypted)
                        return k

        flip (maybe (error "Bad passphrase?")) wkun$ \wkun -> do

        let (uids,subkeys) = break isSubkey subs
            isSubkey p = isKey p && is_subkey p

            (subkeys',remainder) = break isTopKey subkeys
            isTopKey p@(SecretKeyPacket {}) | not (is_subkey p) = True
            isTopKey _ = False

        let parseKeySpec hint spec = case break (==':') spec of
                                    (fmt,_:file) -> (fmt,file)
                                    (file,"") -> (guessKeyFormat hint (key_usage cmd), file)
            (secfmt,secfile) = parseKeySpec 'S' $ seckey cmd
            -- (pubfmt,pubfile) = parseKeySpec 'P' $ pubkey cmd
        Message parsedkey <- readKeyFromFile False secfmt secfile

        let pkf = fingerprint (head parsedkey)
            (prepk,pks) = seek_key (KeyGrip pkf) subkeys'

        g <- newGenIO
        timestamp <- now
        let uids' = do
                        torkey <- parsedkey
                        if key_usage cmd /= "tor"
                         then uids
                         else let ps = makeTorUID (g::SystemRandom)
                                                  timestamp
                                                  wkun
                                                  (keyFlags wkun uids)
                                                  wk
                                                  torkey
                                  toruid = head ps
                              in if toruid `elem` uids then uids else uids ++ ps
        if not (null pks)
            then existingKey (prepk,pks) remainder  wkun wk parsedkey (key_usage cmd) pre uids' subkeys (output cmd) grip
            else newKey                             wkun wk parsedkey (key_usage cmd) pre uids' subkeys (output cmd) grip

    doCmd cmd@(PemFP {}) = do
        let parseKeySpec hint spec = case break (==':') spec of
                                        (fmt,_:file) -> (fmt,file)
                                        (file,"") -> (guessKeyFormat hint ("ssh-host"), file)
            (secfmt,secfile) = parseKeySpec 'S' $ seckey cmd
        Message seckey <- readKeyFromFile False secfmt secfile
        -- Message pubkey <- readKeyFromFile True  pubfmt pubfile
        -- Tor requires public key file... TODO
        -- let torhash sub = maybe "" id $ derToBase32 <$> derRSA sub
        putStrLn $ fingerprint (head seckey) -- ++ " " ++ torhash (head seckey)

    -}

isSameKey a b = sort (key apub) == sort (key bpub)
 where
    apub = secretToPublic a
    bpub = secretToPublic b

existingKey (prepk,pks) remainder wkun wk parsedkey tag pre uids subkeys output_file grip = do
        -- putStrLn "Key already present."
        let pk:trail = pks
            (trailsigs,trail') = span isSignaturePacket trail
            (mysigs,notmines) = partition (endsWith grip . maybe "%bad%" id . signature_issuer)
                                          trailsigs
            endsWith big small = drop (length big - length small) big == small
            vs = map (\sig ->
                      (sig, map (verify (Message [wk]))
                               (signatures $ Message [wk,pk,sig])))
                     mysigs
            (verified,unverified) = partition (not . null . snd) vs
            sorted = sortBy (comparing (Down . signature_time . head . snd)) verified
        -- Note: format allows for signatures of type 0x28 Subkey revocation signature.
        case sorted of
            [] -> do
                    putStrLn "Adding valid signature to existing key..."
                    newKey wkun wk [pk] tag pre uids (trail++prepk++remainder) output_file grip
            (sig,ov):vs -> do
                -- sig exists.
                -- update sig to contain usage@ = tag
                let hs = filter (\p->isNotation p && notation_name p=="usage@") (hashed_subpackets sig)
                    ks = map notation_value hs
                    isNotation (NotationDataPacket {}) = True
                    isNotation _ = False
                    noop = do
                        -- Nothing to do
                        let sec' = pre ++ [wk] ++ uids ++ subkeys
                        putStrLn $ tag ++ " key already present."
                        L.writeFile output_file (encode (Message sec'))
                if tag `elem` ks
                    then noop
                    else do
                        g <- newGenIO
                        timestamp <- now
                        let isCreation (SignatureCreationTimePacket {}) = True
                            isCreation _ = False
                            isExpiration (SignatureExpirationTimePacket {}) = True
                            isExpiration _ = False
                            (cs,ps) = partition isCreation (hashed_subpackets sig)
                            (es,qs) = partition isExpiration ps
                            stamp = listToMaybe . sortBy (comparing Down) $
                                     map unwrap cs where unwrap (SignatureCreationTimePacket x) = x
                            exp = listToMaybe $ sort $
                                     map unwrap es where unwrap (SignatureExpirationTimePacket x) = x
                            expires = liftA2 (+) stamp exp
                        if fmap ( (< timestamp) . fromIntegral) expires == Just True then do
                            putStrLn $ "Unable to update expired signature"
                            noop
                        else do
                            let new_sig = fst $ sign (Message [wkun])
                                                     (SubkeySignature wk
                                                        (head parsedkey)
                                                         [sig'] )
                                                 SHA1
                                                 grip
                                                 timestamp
                                                 (g::SystemRandom)
                                times = (:) (SignatureExpirationTimePacket (fromIntegral timestamp))
                                            $ maybeToList $ do
                                                e <- expires
                                                return $ SignatureExpirationTimePacket (e - fromIntegral timestamp)
                                notation = NotationDataPacket
                                            { notation_name = "usage@"
                                            , notation_value = tag
                                            , human_readable = True }
                                sig' = sig { hashed_subpackets = times ++ [notation] ++ qs }

                        -- noop let sec' = pre ++ [wk] ++ uids ++ subkeys
                                sec' = pre
                                        ++ [wk]
                                        ++ uids
                                        ++ prepk
                                        ++ [pk]
                                        ++ signatures_over new_sig
                                        ++ map fst vs
                                        ++ map fst unverified
                                        ++ notmines
                                        ++ trail'
                                        ++ remainder
                            putStrLn $ "Adding usage@="++tag
                            L.writeFile output_file (encode (Message sec'))
    where
        signature_time ov = case if null cs then ds else cs of
                                [] -> minBound
                                xs -> last (sort xs)
          where
            ps = signatures_over ov
            ss = filter isSignaturePacket ps
            cs = concatMap (concatMap creationTime . hashed_subpackets) ss
            ds = concatMap (concatMap creationTime . unhashed_subpackets) ss
            creationTime (SignatureCreationTimePacket t) = [t]
            creationTime _                               = []

newKey wkun wk parsedkey tag pre uids subkeys output_file grip = do
        g <- newGenIO
        timestamp <- now

        let
                new_sig = fst $ sign (Message [wkun])
                             (SubkeySignature wk
                                              (head parsedkey)
                                              (sigpackets 0x18
                                                          hashed0
                                                          ( IssuerPacket (fingerprint wk)
                                                            : map EmbeddedSignaturePacket (signatures_over back_sig))))
                             SHA1
                             grip
                             timestamp
                             (g::SystemRandom)

                hashed0 =
                    [ KeyFlagsPacket
                        { certify_keys = False
                        , sign_data = False
                        , encrypt_communication = False
                        , encrypt_storage = False
                        , split_key = False
                        , authentication = True
                        , group_key = False }
                    , NotationDataPacket
                        { human_readable = True
                        , notation_name = "usage@"
                        , notation_value = tag
                        }
                    , SignatureCreationTimePacket (fromIntegral timestamp)
                    ]

                subgrip = fingerprint (head parsedkey)

                back_sig = fst $ sign (Message parsedkey)
                             (SubkeySignature wk
                                              (head parsedkey)
                                              (sigpackets 0x19
                                                          hashed0
                                                          [IssuerPacket subgrip]))
                             SHA1
                             subgrip
                             timestamp
                             (g::SystemRandom)

        let sec' = pre ++ [wk] ++ uids ++ parsedkey ++ signatures_over new_sig ++ subkeys
        putStrLn $ listKeys sec'

        L.writeFile output_file (encode (Message sec'))

        {-
        let backsigs = do
                sig <- signatures (Message sec')
                sigover <- signatures_over sig
                subp <- unhashed_subpackets sigover
                -- guard (isEmbeddedSignature subp)
                subp <- maybeToList (backsig subp)
                over <- signatures (Message (filter isKey sec ++ [subp]))
                return over

        -- putStrLn $ PP.ppShow backsigs
        -}

        return ()



groupBindings pub =
        let (sigs,bindings) = getBindings pub
            bindings' = accBindings bindings
            code (c,(m,s),_,_,_) = (fingerprint_material m,-c)
            ownerkey (_,(a,_),_,_,_) = a
            sameMaster (ownerkey->a) (ownerkey->b) = fingerprint_material a==fingerprint_material b
            -- matchgrip ((code,(top,sub), kind, hashed,claimants):_) | fpmatch grip top = True
            -- matchgrip _ = False
            gs = {- filter matchgrip $ -} groupBy sameMaster (sortBy (comparing code) bindings')
        in gs

isTopKey p@(SecretKeyPacket {}) | not (is_subkey p) = True
isTopKey p@(PublicKeyPacket {}) | not (is_subkey p) = True
isTopKey _ = False

seek_key :: KeySpec -> [Packet] -> ([Packet],[Packet])
seek_key (KeyGrip grip) sec = (pre, subs)
  where
    (pre,subs) = break pred sec
    pred p@(SecretKeyPacket {}) = matchpr grip p == grip
    pred p@(PublicKeyPacket {}) = matchpr grip p == grip
    pred _                      = False

seek_key (KeyTag key tag) ps = if null bs
                                then (ps,[])
                                else if null qs
                                 then let (as',bs') = seek_key (KeyTag key tag) (tail bs)
                                      in (as ++ (head bs:as'), bs')
                                 else (reverse (tail qs), head qs : reverse rs ++ bs)
  where
    (as,bs) = break (\p -> isSignaturePacket p
                        && has_tag tag p
                        && isJust (signature_issuer p)
                        && matchpr (fromJust $ signature_issuer p) key == fromJust (signature_issuer p) )
                    ps
    (rs,qs) = break isKey (reverse as)

    has_tag tag p = tag `elem` mapMaybe usage (hashed_subpackets p)
                    || tag `elem` map usageString (mapMaybe keyflags (hashed_subpackets p))

seek_key (KeyUidMatch pat) ps = if null bs
                                then (ps,[])
                                else if null qs
                                 then let (as',bs') = seek_key (KeyUidMatch pat) (tail bs)
                                      in (as ++ (head bs:as'), bs')
                                 else (reverse (tail qs), head qs : reverse rs ++ bs)
  where
    (as,bs) = break (isInfixOf pat . uidStr)
                    ps
    (rs,qs) = break isKey (reverse as)

    uidStr (UserIDPacket s) = s
    uidStr _                = ""

groupTops ps = groupBy (\_ b -> not (isTopKey b)) ps


makeTorUID g timestamp wkun keyflags topkey torkey = uid:signatures_over sig
 where
    torhash sub = maybe "" id $ derToBase32 <$> derRSA sub
    s = "Anonymous <root@" ++ take 16 (torhash torkey) ++ ".onion>"
    uid = UserIDPacket s
    sig = fst $ torsig g topkey wkun uid timestamp keyflags

torsig g topk wkun uid timestamp extras
    = sign (Message [wkun])
                 (CertificationSignature (secretToPublic topk)
                                         uid
                                         (sigpackets 0x13
                                                     subpackets
                                                     subpackets_unh))
                 SHA1
                 (fingerprint wkun) {- (fromJust wkgrip) -}
                 timestamp
                 g
   where
    subpackets = [ SignatureCreationTimePacket (fromIntegral timestamp) ]
                 ++ tsign
                 ++ extras
    subpackets_unh = [IssuerPacket (fingerprint wkun)]
    tsign = if keykey wkun == keykey topk
             then [] -- tsign doesnt make sense for self-signatures
             else [ TrustSignaturePacket 1 120
                  , RegularExpressionPacket regex]
    -- <[^>]+[@.]asdf\.nowhere>$
    regex = "<[^>]+[@.]"++hostname++">$"
    -- regex = username ++ "@" ++ hostname
    -- username = "[a-zA-Z0-9.][-a-zA-Z0-9.]*\\$?" :: String
    hostname = subdomain' pu ++ "\\." ++ topdomain' pu
    pu = parseUID uidstr where UserIDPacket uidstr = uid
    subdomain' = escape . T.unpack . uid_subdomain
    topdomain' = escape . T.unpack . uid_topdomain
    escape s = concatMap echar s
      where
        echar '|' = "\\|"
        echar '*' = "\\*"
        echar '+' = "\\+"
        echar '?' = "\\?"
        echar '.' = "\\."
        echar '^' = "\\^"
        echar '$' = "\\$"
        echar '\\' = "\\\\"
        echar '[' = "\\["
        echar ']' = "\\]"
        echar c = [c]

sigpackets typ hashed unhashed = return $
    signaturePacket
        4 -- version
        typ -- 0x18 subkey binding sig, or 0x19 back-signature
        RSA
        SHA1
        hashed
        unhashed
        0 -- Word16 -- Left 16 bits of the signed hash value
        [] -- [MPI]

keyFlags  wkun uids = keyFlags0 wkun (filter isSignaturePacket uids)
 where
    vs = map (verify (Message [wkun])) (signatures (Message (wkun:uids)))
    ws = map signatures_over vs
    xs = filter null ws

keyFlags0 wkun uidsigs = concat
                      [ keyflags
                      , preferredsym
                      , preferredhash
                      , preferredcomp
                      , features ]

 where
    subs = concatMap hashed_subpackets uidsigs
    keyflags = filterOr isflags subs $
               KeyFlagsPacket { certify_keys = True
                              , sign_data = True
                              , encrypt_communication = False
                              , encrypt_storage = False
                              , split_key = False
                              , authentication = False
                              , group_key = False
                              }
    preferredsym = filterOr ispreferedsym subs $
               PreferredSymmetricAlgorithmsPacket
                              [ AES256
                              , AES192
                              , AES128
                              , CAST5
                              , TripleDES
                              ]
    preferredhash = filterOr ispreferedhash subs $
               PreferredHashAlgorithmsPacket
                              [ SHA256
                              , SHA1
                              , SHA384
                              , SHA512
                              , SHA224
                              ]
    preferredcomp = filterOr ispreferedcomp subs $
               PreferredCompressionAlgorithmsPacket
                              [ ZLIB
                              , BZip2
                              , ZIP
                              ]
    features = filterOr isfeatures subs $
               FeaturesPacket { supports_mdc = True
                              }

    filterOr pred xs def = if null rs then [def] else rs where rs=filter pred xs

    isflags (KeyFlagsPacket {}) = True
    isflags _ = False
    ispreferedsym (PreferredSymmetricAlgorithmsPacket {}) = True
    ispreferedsym _ = False
    ispreferedhash (PreferredHashAlgorithmsPacket {}) = True
    ispreferedhash _ = False
    ispreferedcomp (PreferredCompressionAlgorithmsPacket {}) = True
    ispreferedcomp _ = False
    isfeatures (FeaturesPacket {}) = True
    isfeatures _ = False