Copyright	(c) Galois Inc. 2007-2009 Duncan Coutts 2015
Safe Haskell	None
Language	Haskell2010

Text.JSON.Canonical

Description

Minimal implementation of Canonical JSON.

http://wiki.laptop.org/go/Canonical_JSON

A "canonical JSON" format is provided in order to provide meaningful and repeatable hashes of JSON-encoded data. Canonical JSON is parsable with any full JSON parser, but security-conscious applications will want to verify that input is in canonical form before authenticating any hash or signature on that input.

This implementation is derived from the json parser from the json package, with simplifications to meet the Canonical JSON grammar.

TODO: Known bugs/limitations:

Decoding/encoding Unicode code-points beyond U+00ff is currently broken

Synopsis

data JSValue
- = JSNull
- | JSBool !Bool
- | JSNum !Int54
- | JSString String
- | JSArray [JSValue]
- | JSObject [(String, JSValue)]
data Int54
parseCanonicalJSON :: ByteString -> Either String JSValue
renderCanonicalJSON :: JSValue -> ByteString
prettyCanonicalJSON :: JSValue -> String

Documentation

data JSValue #

Constructors

JSNull
JSBool !Bool
JSNum !Int54
JSString String
JSArray [JSValue]
JSObject [(String, JSValue)]

Instances

Eq JSValue #
Instance details Defined in Text.JSON.Canonical Methods (==) :: JSValue -> JSValue -> Bool # (/=) :: JSValue -> JSValue -> Bool #
Ord JSValue #
Instance details Defined in Text.JSON.Canonical Methods compare :: JSValue -> JSValue -> Ordering # (<) :: JSValue -> JSValue -> Bool # (<=) :: JSValue -> JSValue -> Bool # (>) :: JSValue -> JSValue -> Bool # (>=) :: JSValue -> JSValue -> Bool # max :: JSValue -> JSValue -> JSValue # min :: JSValue -> JSValue -> JSValue #
Read JSValue #
Instance details Defined in Text.JSON.Canonical Methods readsPrec :: Int -> ReadS JSValue # readList :: ReadS [JSValue] # readPrec :: ReadPrec JSValue # readListPrec :: ReadPrec [JSValue] #
Show JSValue #
Instance details Defined in Text.JSON.Canonical Methods showsPrec :: Int -> JSValue -> ShowS # show :: JSValue -> String # showList :: [JSValue] -> ShowS #
Monad m => FromJSON m JSValue #
Instance details Defined in Hackage.Security.Util.JSON Methods fromJSON :: JSValue -> m JSValue #
Monad m => ToJSON m JSValue #
Instance details Defined in Hackage.Security.Util.JSON Methods toJSON :: JSValue -> m JSValue #

data Int54 #

54-bit integer values

JavaScript can only safely represent numbers between -(2^53 - 1) and 2^53 - 1.

TODO: Although we introduce the type here, we don't actually do any bounds checking and just inherit all type class instance from Int64. We should probably define fromInteger to do bounds checking, give different instances for type classes such as Bounded and FiniteBits, etc.

Instances

Bounded Int54 #
Instance details Defined in Text.JSON.Canonical Methods minBound :: Int54 # maxBound :: Int54 #
Enum Int54 #
Instance details Defined in Text.JSON.Canonical Methods succ :: Int54 -> Int54 # pred :: Int54 -> Int54 # toEnum :: Int -> Int54 # fromEnum :: Int54 -> Int # enumFrom :: Int54 -> [Int54] # enumFromThen :: Int54 -> Int54 -> [Int54] # enumFromTo :: Int54 -> Int54 -> [Int54] # enumFromThenTo :: Int54 -> Int54 -> Int54 -> [Int54] #
Eq Int54 #
Instance details Defined in Text.JSON.Canonical Methods (==) :: Int54 -> Int54 -> Bool # (/=) :: Int54 -> Int54 -> Bool #
Integral Int54 #
Instance details Defined in Text.JSON.Canonical Methods quot :: Int54 -> Int54 -> Int54 # rem :: Int54 -> Int54 -> Int54 # div :: Int54 -> Int54 -> Int54 # mod :: Int54 -> Int54 -> Int54 # quotRem :: Int54 -> Int54 -> (Int54, Int54) # divMod :: Int54 -> Int54 -> (Int54, Int54) # toInteger :: Int54 -> Integer #
Data Int54 #
Instance details Defined in Text.JSON.Canonical Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Int54 -> c Int54 # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Int54 # toConstr :: Int54 -> Constr # dataTypeOf :: Int54 -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Int54) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Int54) # gmapT :: (forall b. Data b => b -> b) -> Int54 -> Int54 # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Int54 -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Int54 -> r # gmapQ :: (forall d. Data d => d -> u) -> Int54 -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Int54 -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Int54 -> m Int54 # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Int54 -> m Int54 # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Int54 -> m Int54 #
Num Int54 #
Instance details Defined in Text.JSON.Canonical Methods (+) :: Int54 -> Int54 -> Int54 # (-) :: Int54 -> Int54 -> Int54 # (*) :: Int54 -> Int54 -> Int54 # negate :: Int54 -> Int54 # abs :: Int54 -> Int54 # signum :: Int54 -> Int54 # fromInteger :: Integer -> Int54 #
Ord Int54 #
Instance details Defined in Text.JSON.Canonical Methods compare :: Int54 -> Int54 -> Ordering # (<) :: Int54 -> Int54 -> Bool # (<=) :: Int54 -> Int54 -> Bool # (>) :: Int54 -> Int54 -> Bool # (>=) :: Int54 -> Int54 -> Bool # max :: Int54 -> Int54 -> Int54 # min :: Int54 -> Int54 -> Int54 #
Read Int54 #
Instance details Defined in Text.JSON.Canonical Methods readsPrec :: Int -> ReadS Int54 # readList :: ReadS [Int54] # readPrec :: ReadPrec Int54 # readListPrec :: ReadPrec [Int54] #
Real Int54 #
Instance details Defined in Text.JSON.Canonical Methods toRational :: Int54 -> Rational #
Show Int54 #
Instance details Defined in Text.JSON.Canonical Methods showsPrec :: Int -> Int54 -> ShowS # show :: Int54 -> String # showList :: [Int54] -> ShowS #
Ix Int54 #
Instance details Defined in Text.JSON.Canonical Methods range :: (Int54, Int54) -> [Int54] # index :: (Int54, Int54) -> Int54 -> Int # unsafeIndex :: (Int54, Int54) -> Int54 -> Int inRange :: (Int54, Int54) -> Int54 -> Bool # rangeSize :: (Int54, Int54) -> Int # unsafeRangeSize :: (Int54, Int54) -> Int
PrintfArg Int54 #
Instance details Defined in Text.JSON.Canonical Methods formatArg :: Int54 -> FieldFormatter # parseFormat :: Int54 -> ModifierParser #
Storable Int54 #
Instance details Defined in Text.JSON.Canonical Methods sizeOf :: Int54 -> Int # alignment :: Int54 -> Int # peekElemOff :: Ptr Int54 -> Int -> IO Int54 # pokeElemOff :: Ptr Int54 -> Int -> Int54 -> IO () # peekByteOff :: Ptr b -> Int -> IO Int54 # pokeByteOff :: Ptr b -> Int -> Int54 -> IO () # peek :: Ptr Int54 -> IO Int54 # poke :: Ptr Int54 -> Int54 -> IO () #
Bits Int54 #
Instance details Defined in Text.JSON.Canonical Methods (.&.) :: Int54 -> Int54 -> Int54 # (.\|.) :: Int54 -> Int54 -> Int54 # xor :: Int54 -> Int54 -> Int54 # complement :: Int54 -> Int54 # shift :: Int54 -> Int -> Int54 # rotate :: Int54 -> Int -> Int54 # zeroBits :: Int54 # bit :: Int -> Int54 # setBit :: Int54 -> Int -> Int54 # clearBit :: Int54 -> Int -> Int54 # complementBit :: Int54 -> Int -> Int54 # testBit :: Int54 -> Int -> Bool # bitSizeMaybe :: Int54 -> Maybe Int # bitSize :: Int54 -> Int # isSigned :: Int54 -> Bool # shiftL :: Int54 -> Int -> Int54 # unsafeShiftL :: Int54 -> Int -> Int54 # shiftR :: Int54 -> Int -> Int54 # unsafeShiftR :: Int54 -> Int -> Int54 # rotateL :: Int54 -> Int -> Int54 # rotateR :: Int54 -> Int -> Int54 # popCount :: Int54 -> Int #
FiniteBits Int54 #
Instance details Defined in Text.JSON.Canonical Methods finiteBitSize :: Int54 -> Int # countLeadingZeros :: Int54 -> Int # countTrailingZeros :: Int54 -> Int #
ReportSchemaErrors m => FromJSON m Int54 #
Instance details Defined in Hackage.Security.Util.JSON Methods fromJSON :: JSValue -> m Int54 #
Monad m => ToJSON m Int54 #
Instance details Defined in Hackage.Security.Util.JSON Methods toJSON :: Int54 -> m JSValue #

parseCanonicalJSON :: ByteString -> Either String JSValue #

Parse a canonical JSON format string as a JSON value. The input string does not have to be in canonical form, just in the "canonical JSON" format.

Use renderCanonicalJSON to convert into canonical form.

renderCanonicalJSON :: JSValue -> ByteString #

Render a JSON value in canonical form. This rendered form is canonical and so allows repeatable hashes.

For pretty printing, see prettyCanonicalJSON.

NB: Canonical JSON's string escaping rules deviate from RFC 7159 JSON which requires

"All Unicode characters may be placed within the quotation marks, except for the characters that must be escaped: quotation mark, reverse solidus, and the control characters (U+0000 through U+001F)."

Whereas the current specification of Canonical JSON explicitly requires to violate this by only escaping the quotation mark and the reverse solidus. This, however, contradicts Canonical JSON's statement that "Canonical JSON is parsable with any full JSON parser"

Consequently, Canonical JSON is not a proper subset of RFC 7159.

prettyCanonicalJSON :: JSValue -> String #

Render a JSON value in a reasonable human-readable form. This rendered form is not the canonical form used for repeatable hashes, use renderCanonicalJSON for that.