Copyright | (c) Joseph Abrahamson 2013 |
---|---|
License | MIT |
Maintainer | me@jspha.com |
Stability | experimental |
Portability | non-portable |
Safe Haskell | None |
Language | Haskell2010 |
Scalar multiplication: Crypto.Saltine.Core.ScalarMult
The mult
function multiplies a group element by an integer of
length multScalar
. It returns the resulting group element
of length mult
. The multBase
function multiplies a
standard group element by an integer of length
multScalar
. It returns the resulting group element of
length mult
.
The correspondence between strings and group elements depends on
the primitive implemented by mult
. The correspondence is not
necessarily injective in either direction, but it is compatible
with scalar multiplication in the group. The correspondence does
not necessarily include all group elements, but it does include all
strings; i.e., every string represents at least one group element.
The correspondence between strings and integers also depends on the
primitive implemented by mult
. Every string represents at least
one integer.
mult
is designed to be strong as a component of various
well-known "hashed Diffie–Hellman" applications. In particular,
it is designed to make the "computational Diffie–Hellman" problem
(CDH) difficult with respect to the standard base. mult
is also
designed to make CDH difficult with respect to other nontrivial
bases. In particular, if a represented group element has small
order, then it is annihilated by all represented scalars. This
feature allows protocols to avoid validating membership in the
subgroup generated by the standard base.
NaCl does not make any promises regarding the "decisional Diffie–Hellman" problem (DDH), the "static Diffie–Hellman" problem (SDH), etc. Users are responsible for hashing group elements.
mult
is the function crypto_scalarmult_curve25519
specified in
"Cryptography in NaCl", Sections 2, 3, and 4
(http://nacl.cr.yp.to/valid.html). This function is conjectured
to be strong. For background see Bernstein, "Curve25519: new
Diffie-Hellman speed records," Lecture Notes in Computer Science
3958 (2006), 207–228, http://cr.yp.to/papers.html#curve25519.
This is version 2010.08.30 of the scalarmult.html web page.
Synopsis
- data Scalar
- data GroupElement
- mult :: Scalar -> GroupElement -> GroupElement
- multBase :: Scalar -> GroupElement
Documentation
A scalar integer.
Instances
Eq Scalar Source # | |
Data Scalar Source # | |
Defined in Crypto.Saltine.Core.ScalarMult gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Scalar -> c Scalar # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Scalar # toConstr :: Scalar -> Constr # dataTypeOf :: Scalar -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Scalar) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Scalar) # gmapT :: (forall b. Data b => b -> b) -> Scalar -> Scalar # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Scalar -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Scalar -> r # gmapQ :: (forall d. Data d => d -> u) -> Scalar -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Scalar -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Scalar -> m Scalar # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Scalar -> m Scalar # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Scalar -> m Scalar # | |
Ord Scalar Source # | |
Generic Scalar Source # | |
Hashable Scalar Source # | |
Defined in Crypto.Saltine.Core.ScalarMult | |
IsEncoding Scalar Source # | |
Defined in Crypto.Saltine.Core.ScalarMult encode :: Scalar -> ByteString Source # decode :: ByteString -> Maybe Scalar Source # encoded :: (Choice p, Applicative f) => p Scalar (f Scalar) -> p ByteString (f ByteString) Source # | |
type Rep Scalar Source # | |
Defined in Crypto.Saltine.Core.ScalarMult type Rep Scalar = D1 ('MetaData "Scalar" "Crypto.Saltine.Core.ScalarMult" "saltine-0.1.1.1-KbVmRAcWBV25w8Dlelbdig" 'True) (C1 ('MetaCons "Sc" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 ByteString))) |
data GroupElement Source #
A group element.
Instances
mult :: Scalar -> GroupElement -> GroupElement Source #
multBase :: Scalar -> GroupElement Source #