hjugement-protocol/hjugement-protocol.cabal

   1 name: hjugement-protocol
   2 -- PVP:  +-+------- breaking API changes
   3 --       | | +----- non-breaking API additions
   4 --       | | | +--- code changes with no API change
   5 version: 0.0.0.20190415
   6 category: Politic
   7 synopsis: A fully distributed threshold cryptosystem for the Majority Judgment.
   8 description:
   9   This library implements an online voting protocol
  10   known as <https://eprint.iacr.org/2013/177.pdf Helios-C> (Helios with Credentials)
  11   which is:
  12   .
  13   * /fully correct/: the published result are proven to correspond
  14     to the (sum of) intended votes of the voters,
  15     while accounting for a malicious bulletin board (BB) (adding fake ballots)
  16     by requiring a registration authority (RA)
  17     (responsible for generating and sending voters' credentials).
  18     Assuming that the BB and the RA are not simultaneously dishonest.
  19   .
  20   * /verifiable/: voters are able to check that:
  21     their ballots did contribute to the outcome (/individual verifiability/),
  22     and that the tallying authorities did their job properly (/universal verifiability/).
  23   .
  24   * /private/: the identities of the voters who cast a vote are not publicly revealed.
  25   .
  26   Credentials:
  27     A voter's credentials is a private key (the signing key)
  28     that has a public part (the verification key).
  29     The association between the public part and the corresponding voter’s identity
  30     does not need to be known, and actually should not be disclosed to satisfy
  31     e.g. the French requirements regarding voting systems.
  32     Using credentials prevent the submission of duplicated ballots
  33     (because they are added as an additional input to the random oracle
  34     in the /non-interactive zero-knowledge/ (NIZK) proofs for ciphertext well-formedness).
  35     This allows a testing of duplicates which depends only on the size of the number of voters,
  36     and thus enables Helios-C to scale for larger elections while attaining correctness.
  37   .
  38   In this protocol :
  39   .
  40   * Ballots are encrypted using public-key cryptography
  41     secured by the /Discrete Logarithm problem/:
  42     finding @x@ in @g^x `mod` p@, where @p@ is a large prime
  43     and @g@ a generator of @Gq@, the multiplicative subgroup of @Fp@
  44     (the finite prime field whose characteristic is @p@) of order @q@.
  45     Here, @p@ is 2048-bit and @q@ is 256-bit.
  46     The signing (Schnorr-like), the encrypting (ElGamal-like)
  47     and the /Decisional Diffe Hellman/ (DDH) assumption,
  48     all rely on the hardness of that problem.
  49   * Ballots are added without being decrypted
  50     because adding ciphertexts then decrypting
  51     is like decrypting then adding plaintexts (/additive homomorphism/).
  52     This uses an /ElGamal encryption scheme/ with
  53     a transformation so that from being a /multiplicative homomorphism/
  54     it becomes an /additive homomorphism/.
  55     Which requires to solve the /Discrete Logarithm Problem/
  56     for numbers in the order of the number of voters,
  57     which is not hard for small numbers (with a lookup table as here,
  58     or with Pollard’s rho algorithm for logarithms).
  59   * A Pedersen's /distributed key generation/ (DKG) protocol
  60     coupled with ElGamal keys (under the DDH assumption),
  61     is used to have a fully distributed semantically secure encryption.
  62   * The /Schnorr protocol/ is used to prove that a voter has knowledge
  63     of the secret key used to encrypt their votes.
  64   * The /Chaum-Pedersen protocol/ (proving that equality of discrete logarithms)
  65     is used to prove that two given ciphertexts
  66     belonging to two voters with different public credentials,
  67     are well-formed (encrypting a 0 or a 1) without decrypting them.
  68     Which is known as a /Disjunctive Chaum-Pedersen/ proof of partial knowledge.
  69   * A /Fiat-Shamir transformation/ is used
  70     to transform the /interactive zero-knowledge/ (IZK) /Chaum-Pedersen protocol/
  71     into a /non-interactive zero-knowledge/ (NIZK) proof, using a SHA256 hash.
  72 extra-doc-files:
  73 license: GPL-3
  74 license-file: COPYING
  75 stability: experimental
  76 author:      Julien Moutinho <julm+hjugement@autogeree.net>
  77 maintainer:  Julien Moutinho <julm+hjugement@autogeree.net>
  78 bug-reports: Julien Moutinho <julm+hjugement@autogeree.net>
  79 -- homepage:
  80
  81 build-type: Simple
  82 cabal-version: 1.24
  83 tested-with: GHC==8.4.4
  84 extra-source-files:
  85   stack.yaml
  86 extra-tmp-files:
  87
  88 Source-Repository head
  89  location: git://git.autogeree.net/hjugement
  90  type:     git
  91
  92 Library
  93   exposed-modules:
  94     Protocol.Arith
  95     Protocol.Credential
  96   default-language: Haskell2010
  97   default-extensions:
  98     AllowAmbiguousTypes
  99     DefaultSignatures
 100     FlexibleContexts
 101     FlexibleInstances
 102     GeneralizedNewtypeDeriving
 103     MonoLocalBinds
 104     MultiParamTypeClasses
 105     NamedFieldPuns
 106     NoImplicitPrelude
 107     NoMonomorphismRestriction
 108     ScopedTypeVariables
 109     TypeApplications
 110     TypeFamilies
 111     UndecidableInstances
 112   ghc-options:
 113     -Wall
 114     -Wincomplete-uni-patterns
 115     -Wincomplete-record-updates
 116     -fno-warn-tabs
 117     -- -fhide-source-paths
 118   build-depends:
 119       base >= 4.6 && < 5
 120     , bytestring >= 0.10
 121     , containers >= 0.5
 122     , cryptonite >= 0.25
 123     , hashable >= 1.2.6
 124     , memory >= 0.14
 125     , random >= 1.1
 126     , reflection >= 2.1
 127     , transformers >= 0.5
 128     , unordered-containers >= 0.2.8
 129
 130 Test-Suite hjugement-protocol-test
 131   type: exitcode-stdio-1.0
 132   hs-source-dirs: test
 133   main-is: Main.hs
 134   other-modules:
 135     HUnit
 136     HUnit.Arith
 137     HUnit.Credential
 138     HUnit.Utils
 139     -- QuickCheck
 140   default-language: Haskell2010
 141   default-extensions:
 142     AllowAmbiguousTypes
 143     DefaultSignatures
 144     FlexibleContexts
 145     FlexibleInstances
 146     GeneralizedNewtypeDeriving
 147     MonoLocalBinds
 148     MultiParamTypeClasses
 149     NamedFieldPuns
 150     NoImplicitPrelude
 151     NoMonomorphismRestriction
 152     ScopedTypeVariables
 153     TypeApplications
 154     TypeFamilies
 155     UndecidableInstances
 156   ghc-options:
 157     -Wall
 158     -Wincomplete-uni-patterns
 159     -Wincomplete-record-updates
 160     -fno-warn-tabs
 161     -- -fhide-source-paths
 162   build-depends:
 163       hjugement-protocol
 164     , base >= 4.6 && < 5
 165     , containers >= 0.5
 166     , hashable >= 1.2.6
 167     , QuickCheck >= 2.0
 168     , random >= 1.1
 169     , reflection >= 2.1
 170     , tasty >= 0.11
 171     , tasty-hunit >= 0.9
 172     , tasty-quickcheck
 173     , text >= 1.2
 174     , transformers >= 0.5
 175     , unordered-containers >= 0.2.8