web: continue to purescriptify Cryptography

[majurity.git] / hjugement-protocol / src / Voting / Protocol / Trustee / Indispensable.hs

diff --git a/hjugement-protocol/src/Voting/Protocol/Trustee/Indispensable.hs b/hjugement-protocol/src/Voting/Protocol/Trustee/Indispensable.hs
index b211679d8bf7ff2fa313312903e591b208490514..58bde8d43a7a8c77506f1a242a05e5f4f88c7d10 100644 (file)
--- a/hjugement-protocol/src/Voting/Protocol/Trustee/Indispensable.hs
+++ b/hjugement-protocol/src/Voting/Protocol/Trustee/Indispensable.hs
@@ -7,14 +7,16 @@ module Voting.Protocol.Trustee.Indispensable where
 import Control.DeepSeq (NFData)
 import Control.Monad (Monad(..), foldM, unless)
 import Control.Monad.Trans.Except (ExceptT(..), throwE)
-import Data.Aeson (ToJSON(..),FromJSON(..),(.:),(.=))
+import Data.Aeson (ToJSON(..), FromJSON(..), (.:), (.=))
 import Data.Eq (Eq(..))
 import Data.Function (($))
 import Data.Functor ((<$>))
 import Data.Maybe (maybe)
+import Data.Reflection (Reifies(..))
 import Data.Semigroup (Semigroup(..))
 import Data.Tuple (fst)
 import GHC.Generics (Generic)
+import System.Random (RandomGen)
 import Text.Show (Show(..))
 import qualified Control.Monad.Trans.State.Strict as S
 import qualified Data.Aeson as JSON
@@ -22,15 +24,16 @@ import qualified Data.ByteString as BS
 import qualified Data.List as List
 
 import Voting.Protocol.Utils
-import Voting.Protocol.FFC
+import Voting.Protocol.Arithmetic
+import Voting.Protocol.Version
+import Voting.Protocol.Cryptography
 import Voting.Protocol.Credential
-import Voting.Protocol.Election
 import Voting.Protocol.Tally
 
 -- * Type 'TrusteePublicKey'
-data TrusteePublicKey c = TrusteePublicKey
- { trustee_PublicKey      :: !(PublicKey c)
- , trustee_SecretKeyProof :: !(Proof c)
+data TrusteePublicKey crypto v c = TrusteePublicKey
+ { trustee_PublicKey      :: !(PublicKey crypto c)
+ , trustee_SecretKeyProof :: !(Proof crypto v c)
        -- ^ NOTE: It is important to ensure
        -- that each trustee generates its key pair independently
        -- of the 'PublicKey's published by the other trustees.
@@ -44,8 +47,14 @@ data TrusteePublicKey c = TrusteePublicKey
        -- must 'prove' knowledge of the corresponding 'SecretKey'.
        -- Which is done in 'proveIndispensableTrusteePublicKey'
        -- and 'verifyIndispensableTrusteePublicKey'.
- } deriving (Eq,Show,Generic,NFData)
-instance ToJSON (TrusteePublicKey c) where
+ } deriving (Generic)
+deriving instance Eq (G crypto c) => Eq (TrusteePublicKey crypto v c)
+deriving instance (Show (G crypto c), Show (PublicKey crypto c)) => Show (TrusteePublicKey crypto v c)
+deriving instance NFData (G crypto c) => NFData (TrusteePublicKey crypto v c)
+instance
+ ( Reifies v Version
+ , ToJSON (G crypto c)
+ ) => ToJSON (TrusteePublicKey crypto v c) where
        toJSON TrusteePublicKey{..} =
                JSON.object
                 [ "pok"        .= trustee_SecretKeyProof
@@ -56,24 +65,26 @@ instance ToJSON (TrusteePublicKey c) where
                 (  "pok"        .= trustee_SecretKeyProof
                 <> "public_key" .= trustee_PublicKey
                 )
-instance Reifies c FFC => FromJSON (TrusteePublicKey c) where
+instance
+ ( Reifies v Version
+ , CryptoParams crypto c
+ ) => FromJSON (TrusteePublicKey crypto v c) where
        parseJSON = JSON.withObject "TrusteePublicKey" $ \o -> do
                trustee_PublicKey <- o .: "public_key"
                trustee_SecretKeyProof <- o .: "pok"
                return TrusteePublicKey{..}
 
--- ** Type 'ErrorTrusteePublicKey'
-data ErrorTrusteePublicKey
- =   ErrorTrusteePublicKey_WrongProof
-     -- ^ The 'trustee_SecretKeyProof' is wrong.
- deriving (Eq,Show)
+-- ** Generating a 'TrusteePublicKey'
 
 -- | @('proveIndispensableTrusteePublicKey' trustSecKey)@
 -- returns the 'PublicKey' associated to 'trustSecKey'
 -- and a 'Proof' of its knowledge.
 proveIndispensableTrusteePublicKey ::
- Reifies c FFC => Monad m => RandomGen r =>
- SecretKey c -> S.StateT r m (TrusteePublicKey c)
+ Reifies v Version =>
+ CryptoParams crypto c =>
+ Key crypto =>
+ Monad m => RandomGen r =>
+ SecretKey crypto c -> S.StateT r m (TrusteePublicKey crypto v c)
 proveIndispensableTrusteePublicKey trustSecKey = do
        let trustee_PublicKey = publicKey trustSecKey
        trustee_SecretKeyProof <-
@@ -81,45 +92,69 @@ proveIndispensableTrusteePublicKey trustSecKey = do
                        hash (indispensableTrusteePublicKeyStatement trustee_PublicKey)
        return TrusteePublicKey{..}
 
+-- ** Checking a 'TrusteePublicKey' before incorporating it into the 'Election''s 'PublicKey'
+
 -- | @('verifyIndispensableTrusteePublicKey' trustPubKey)@
 -- returns 'True' iif. the given 'trustee_SecretKeyProof'
 -- does 'prove' that the 'SecretKey' associated with
 -- the given 'trustee_PublicKey' is known by the trustee.
 verifyIndispensableTrusteePublicKey ::
- Reifies c FFC => Monad m =>
- TrusteePublicKey c ->
+ Reifies v Version =>
+ CryptoParams crypto c =>
+ Monad m =>
+ TrusteePublicKey crypto v c ->
  ExceptT ErrorTrusteePublicKey m ()
 verifyIndispensableTrusteePublicKey TrusteePublicKey{..} =
-       unless ((proof_challenge trustee_SecretKeyProof ==) $
-       hash
-        (indispensableTrusteePublicKeyStatement trustee_PublicKey)
-        [commit trustee_SecretKeyProof groupGen trustee_PublicKey]) $
+       unless (
+               proof_challenge trustee_SecretKeyProof == hash
+                (indispensableTrusteePublicKeyStatement trustee_PublicKey)
+                [commit trustee_SecretKeyProof groupGen trustee_PublicKey]
+        ) $
                throwE ErrorTrusteePublicKey_WrongProof
 
+-- ** Type 'ErrorTrusteePublicKey'
+data ErrorTrusteePublicKey
+ =   ErrorTrusteePublicKey_WrongProof
+     -- ^ The 'trustee_SecretKeyProof' is wrong.
+ deriving (Eq,Show)
+
 -- ** Hashing
-indispensableTrusteePublicKeyStatement :: PublicKey c -> BS.ByteString
+indispensableTrusteePublicKeyStatement ::
+ CryptoParams crypto c =>
+ PublicKey crypto c -> BS.ByteString
 indispensableTrusteePublicKeyStatement trustPubKey =
        "pok|"<>bytesNat trustPubKey<>"|"
 
 -- * 'Election''s 'PublicKey'
 
+-- ** Generating an 'Election''s 'PublicKey' from multiple 'TrusteePublicKey's.
+
 combineIndispensableTrusteePublicKeys ::
- Reifies c FFC => [TrusteePublicKey c] -> PublicKey c
+ CryptoParams crypto c =>
+ [TrusteePublicKey crypto v c] -> PublicKey crypto c
 combineIndispensableTrusteePublicKeys =
        List.foldr (\TrusteePublicKey{..} -> (trustee_PublicKey *)) one
 
+-- ** Checking the trustee's 'DecryptionShare's before decrypting an 'EncryptedTally'.
+
 verifyIndispensableDecryptionShareByTrustee ::
- Reifies c FFC => Monad m =>
- EncryptedTally c -> [PublicKey c] -> [DecryptionShare c] ->
+ Reifies v Version =>
+ CryptoParams crypto c =>
+ Monad m =>
+ EncryptedTally crypto v c -> [PublicKey crypto c] -> [DecryptionShare crypto v c] ->
  ExceptT ErrorTally m ()
 verifyIndispensableDecryptionShareByTrustee encByChoiceByQuest =
        isoZipWithM_ (throwE $ ErrorTally_NumberOfTrustees)
         (verifyDecryptionShare encByChoiceByQuest)
 
+-- ** Decrypting an 'EncryptedTally' from multiple 'TrusteePublicKey's.
+
 -- | @('combineDecryptionShares' pubKeyByTrustee decShareByTrustee)@
 -- returns the 'DecryptionFactor's by choice by 'Question'
 combineIndispensableDecryptionShares ::
- Reifies c FFC => [PublicKey c] -> DecryptionShareCombinator c
+ Reifies v Version =>
+ CryptoParams crypto c =>
+ [PublicKey crypto c] -> DecryptionShareCombinator crypto v c
 combineIndispensableDecryptionShares
  pubKeyByTrustee
  encByChoiceByQuest