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@@ -4,44 +4,79 @@
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extern const curvepoint_fp_t bn_curvegen;
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extern const scalar_t bn_n;
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-
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-// This needs to be here so it's "defined", but it doesn't always seem to actually, uh, execute, so you do it over in the constructor
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-Curvepoint PrsonaServer::elGamalGenerator = Curvepoint();
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-Scalar PrsonaServer::scalarN = Scalar();
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-Scalar PrsonaServer::defaultTally = Scalar();
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-Scalar PrsonaServer::defaultVote = Scalar();
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-bool PrsonaServer::malicious_server = false;
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-bool PrsonaServer::malicious_client = false;
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-
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+const int MAX_ALLOWED_VOTE = 2;
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+
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+/* These lines need to be here so these static variables are defined,
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+ * but in C++ putting code here doesn't actually execute
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+ * (or at least, with g++, whenever it would execute is not at a useful time)
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+ * so we have an init() function to actually put the correct values in them. */
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+Curvepoint PrsonaServer::EL_GAMAL_GENERATOR = Curvepoint();
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+Curvepoint PrsonaServer::EL_GAMAL_BLIND_GENERATOR = Curvepoint();
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+Scalar PrsonaServer::SCALAR_N = Scalar();
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+Scalar PrsonaServer::DEFAULT_TALLY = Scalar();
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+Scalar PrsonaServer::DEFAULT_VOTE = Scalar();
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+bool PrsonaServer::SERVER_IS_MALICIOUS = false;
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+bool PrsonaServer::CLIENT_IS_MALICIOUS = false;
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+
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+/********************
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+ * PUBLIC FUNCTIONS *
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+ ********************/
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+
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+/*
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+ * CONSTRUCTORS
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+ */
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+
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+// Used to generate the first server; instantiates BGN for the first time
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PrsonaServer::PrsonaServer()
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{
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- elGamalGenerator = Curvepoint(bn_curvegen);
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- scalarN = Scalar(bn_n);
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- defaultTally = Scalar(1);
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- defaultVote = Scalar(0);
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+ currentSeed.set_random();
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+}
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+
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+// Used for all other servers, so they have the same BGN parameters
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+PrsonaServer::PrsonaServer(const BGN& other_bgn)
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+: bgn_system(other_bgn)
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+{
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+ currentSeed.set_random();
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+}
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+/*
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+ * SETUP FUNCTIONS
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+ */
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+
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+// Must be called once before any usage of this class
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+Curvepoint PrsonaServer::init()
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+{
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Scalar lambda;
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lambda.set_random();
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- elGamalBlindGenerator = elGamalGenerator * lambda;
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+ EL_GAMAL_GENERATOR = Curvepoint(bn_curvegen);
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+ EL_GAMAL_BLIND_GENERATOR = EL_GAMAL_GENERATOR * lambda;
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+ SCALAR_N = Scalar(bn_n);
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+ DEFAULT_TALLY = Scalar(1);
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+ DEFAULT_VOTE = Scalar(1);
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- currentSeed.set_random();
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+ return EL_GAMAL_BLIND_GENERATOR;
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}
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-PrsonaServer::PrsonaServer(const BGN& other_bgn, const Curvepoint& other_blind_gen)
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-: bgn_system(other_bgn), elGamalBlindGenerator(other_blind_gen)
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+// Call this (once) if using malicious-security servers
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+void PrsonaServer::set_server_malicious()
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{
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- currentSeed.set_random();
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+ SERVER_IS_MALICIOUS = true;
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}
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-void PrsonaServer::set_malicious_server()
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+// Call this (once) if using malicious-security clients
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+void PrsonaServer::set_client_malicious()
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{
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- malicious_server = true;
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+ CLIENT_IS_MALICIOUS = true;
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}
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-void PrsonaServer::set_malicious_client()
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+/*
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+ * BASIC PUBLIC SYSTEM INFO GETTERS
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+ */
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+
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+Curvepoint PrsonaServer::get_blinding_generator()
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{
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- malicious_client = true;
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+ return EL_GAMAL_BLIND_GENERATOR;
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}
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BGNPublicKey PrsonaServer::get_bgn_public_key() const
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@@ -49,37 +84,71 @@ BGNPublicKey PrsonaServer::get_bgn_public_key() const
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return bgn_system.get_public_key();
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}
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-Curvepoint PrsonaServer::get_blinding_generator() const
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-{
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- return elGamalBlindGenerator;
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-}
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+/*
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+ * FRESH GENERATOR CALCULATION
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+ */
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-Curvepoint PrsonaServer::add_seed_to_generator(Proof& pi, const Curvepoint& currGenerator) const
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+// To calculate the current epoch's generator, start from the base generator,
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+// then have every server call this function on it iteratively (in any order).
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+Curvepoint PrsonaServer::add_curr_seed_to_generator(
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+ const Curvepoint& currGenerator) const
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{
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- pi = generate_valid_fresh_generator_proof(pi);
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-
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return currGenerator * currentSeed;
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}
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-Curvepoint PrsonaServer::add_next_seed_to_generator(Proof& pi, const Curvepoint& currGenerator) const
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+// To calculate the next epoch's generator, start from the base generator,
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+// then have every server call this function on it iteratively (in any order).
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+Curvepoint PrsonaServer::add_next_seed_to_generator(
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+ const Curvepoint& currGenerator) const
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{
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- pi = generate_valid_fresh_generator_proof(pi);
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-
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return currGenerator * nextSeed;
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}
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-std::vector<CurveBipoint> PrsonaServer::get_current_votes_by(Proof& pi, const Curvepoint& shortTermPublicKey) const
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+/*
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+ * ENCRYPTED DATA GETTERS
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+ */
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+
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+/* Call this in order to get the current encrypted votes cast by a given user
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+ * (who is identified by their short term public key).
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+ * In practice, this is intended for clients,
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+ * who need to know their current votes in order to rerandomize them. */
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+std::vector<CurveBipoint> PrsonaServer::get_current_votes_by(
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+ Proof& pi, const Curvepoint& shortTermPublicKey) const
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{
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std::vector<CurveBipoint> retval;
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size_t voteSubmitter = binary_search(shortTermPublicKey);
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retval = voteMatrix[voteSubmitter];
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pi = generate_votes_valid_proof(retval, shortTermPublicKey);
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+ return retval;
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+}
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+
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+/* Call this in order to get the current encrypted tally of a given user
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+ * (who is identified by their short term public key).
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+ * In practice, this is intended for clients, so that the servers vouch
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+ * for their ciphertexts being valid as part of their reputation proofs. */
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+EGCiphertext PrsonaServer::get_current_tally(
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+ Proof& pi, const Curvepoint& shortTermPublicKey) const
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+{
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+ EGCiphertext retval;
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+ size_t tallyOwner = binary_search(shortTermPublicKey);
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+ retval = currentUserEncryptedTallies[tallyOwner];
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+ pi = currentTallyProofs[tallyOwner];
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return retval;
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}
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-void PrsonaServer::add_new_client(const Proof& proofOfValidKey, Proof& proofOfValidAddition, const Curvepoint& shortTermPublicKey)
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+/*
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+ * CLIENT INTERACTIONS
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+ */
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+
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+/* Add a new client (who is identified only by their short term public key)
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+ * One server will do this, then ask all other servers to import their
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+ * (proven) exported data. */
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+void PrsonaServer::add_new_client(
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+ const Proof& proofOfValidKey,
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+ Proof& proofOfValidAddition,
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+ const Curvepoint& shortTermPublicKey)
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{
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if (!verify_valid_key_proof(proofOfValidKey, shortTermPublicKey))
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{
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@@ -89,12 +158,27 @@ void PrsonaServer::add_new_client(const Proof& proofOfValidKey, Proof& proofOfVa
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currentPseudonyms.push_back(shortTermPublicKey);
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- TwistBipoint newTalliedVote;
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- bgn_system.encrypt(newTalliedVote, defaultTally);
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- previousVoteTally.push_back(newTalliedVote);
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-
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- CurveBipoint encryptedDefaultVote;
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- bgn_system.encrypt(encryptedDefaultVote, defaultVote);
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+ // The first epoch's score for a new user will be low,
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+ // but will typically converge on an average score quickly
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+ TwistBipoint encryptedDefaultTally;
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+ bgn_system.encrypt(encryptedDefaultTally, DEFAULT_TALLY);
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+ previousVoteTallies.push_back(encryptedDefaultTally);
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+
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+ Scalar mask;
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+ mask.set_random();
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+ EGCiphertext newUserEncryptedTally;
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+ newUserEncryptedTally.mask = shortTermPublicKey * mask;
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+ newUserEncryptedTally.encryptedMessage =
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+ currentFreshGenerator * mask +
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+ get_blinding_generator() * DEFAULT_TALLY;
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+ currentUserEncryptedTallies.push_back(newUserEncryptedTally);
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+ currentTallyProofs.push_back(
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+ generate_valid_default_tally_proof(newUserEncryptedTally, mask));
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+
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+ // Users are defaulted to casting a neutral vote for others.
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+ CurveBipoint encryptedDefaultVote, encryptedSelfVote;
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+ bgn_system.encrypt(encryptedDefaultVote, DEFAULT_VOTE);
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+ bgn_system.encrypt(encryptedSelfVote, Scalar(MAX_ALLOWED_VOTE));
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std::vector<CurveBipoint> newRow;
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for (size_t i = 0; i < voteMatrix.size(); i++)
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{
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@@ -104,17 +188,21 @@ void PrsonaServer::add_new_client(const Proof& proofOfValidKey, Proof& proofOfVa
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encryptedDefaultVote = bgn_system.rerandomize(encryptedDefaultVote);
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newRow.push_back(encryptedDefaultVote);
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}
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-
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- encryptedDefaultVote = bgn_system.rerandomize(encryptedDefaultVote);
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- newRow.push_back(encryptedDefaultVote);
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+ // Because we are adding the new user to the end (and then sorting it),
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+ // this last element (bottom right corner) is always the self vote.
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+ newRow.push_back(encryptedSelfVote);
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voteMatrix.push_back(newRow);
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- order_data();
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+ order_data(proofOfValidAddition);
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proofOfValidAddition = generate_proof_of_added_user(shortTermPublicKey);
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}
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-void PrsonaServer::receive_vote(const Proof& pi, const std::vector<CurveBipoint>& votes, const Curvepoint& shortTermPublicKey)
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+// Receive a new vote row from a user (identified by short term public key).
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+void PrsonaServer::receive_vote(
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+ const Proof& pi,
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+ const std::vector<CurveBipoint>& votes,
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+ const Curvepoint& shortTermPublicKey)
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{
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if (!verify_vote_proof(pi, votes, shortTermPublicKey))
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{
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@@ -126,12 +214,34 @@ void PrsonaServer::receive_vote(const Proof& pi, const std::vector<CurveBipoint>
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voteMatrix[voteSubmitter] = votes;
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}
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+/*********************
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+ * PRIVATE FUNCTIONS *
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+ *********************/
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+
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+/*
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+ * CONSTRUCTOR HELPERS
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+ */
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+
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const BGN& PrsonaServer::get_bgn_details() const
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{
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return bgn_system;
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}
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-std::vector<Scalar> PrsonaServer::tally_scores(Proof& pi)
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+void PrsonaServer::initialize_fresh_generator(const Curvepoint& firstGenerator)
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+{
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+ currentFreshGenerator = firstGenerator;
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+}
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+
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+/*
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+ * SCORE TALLYING
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+ */
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+
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+/* Calculate scores homomorphically (as an individual server would normally)
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+ * and then decrypt them (which the servers would normally work together to do).
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+ *
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+ * Note that since these calculations are just for us, we don't need to do any
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+ * expensive rerandomizations of intermediate values. */
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+std::vector<Scalar> PrsonaServer::tally_scores(std::vector<Proof>& tallyProofs)
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{
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std::vector<Quadripoint> BGNEncryptedTallies;
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std::vector<Scalar> decryptedTallies;
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@@ -139,122 +249,179 @@ std::vector<Scalar> PrsonaServer::tally_scores(Proof& pi)
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{
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std::vector<Quadripoint> weightedVotes;
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- for (size_t j = 0; j < previousVoteTally.size(); j++)
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+ // ZIP
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+ for (size_t j = 0; j < previousVoteTallies.size(); j++)
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{
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- Quadripoint curr = bgn_system.homomorphic_multiplication_no_rerandomize(voteMatrix[j][i], previousVoteTally[j]);
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+ Quadripoint curr =
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+ bgn_system.homomorphic_multiplication_no_rerandomize(
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+ voteMatrix[j][i], previousVoteTallies[j]);
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+
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weightedVotes.push_back(curr);
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}
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+ // FOLDL
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Quadripoint currEncryptedTally = weightedVotes[0];
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for (size_t j = 1; j < weightedVotes.size(); j++)
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- currEncryptedTally = bgn_system.homomorphic_addition_no_rerandomize(currEncryptedTally, weightedVotes[j]);
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+ {
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+ currEncryptedTally =
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+ bgn_system.homomorphic_addition_no_rerandomize(
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+ currEncryptedTally, weightedVotes[j]);
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+ }
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+ // DECRYPT
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decryptedTallies.push_back(bgn_system.decrypt(currEncryptedTally));
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+ tallyProofs.push_back(
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+ generate_proof_of_correct_tally(
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+ currEncryptedTally, decryptedTallies[i]));
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}
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- pi = generate_proof_of_correct_tally(BGNEncryptedTallies, decryptedTallies);
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-
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return decryptedTallies;
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}
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+/* Calculate what the maximum possible score this round was (that is,
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+ * given the current user weights, what was the highest possible score?).
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+ *
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+ * As with individual scores, this also does the decryption that servers
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+ * would ordinarily work together to form. */
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Scalar PrsonaServer::get_max_possible_score(Proof& pi)
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{
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- TwistBipoint currEncryptedVal = previousVoteTally[0];
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- for (size_t i = 1; i < previousVoteTally.size(); i++)
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- currEncryptedVal = bgn_system.homomorphic_addition_no_rerandomize(currEncryptedVal, previousVoteTally[i]);
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+ // FOLDL
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+ TwistBipoint currEncryptedVal = previousVoteTallies[0];
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+ for (size_t i = 1; i < previousVoteTallies.size(); i++)
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+ {
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+ currEncryptedVal =
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+ bgn_system.homomorphic_addition_no_rerandomize(
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+ currEncryptedVal, previousVoteTallies[i]);
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+ }
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+ // DECRYPT
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Scalar retval = bgn_system.decrypt(currEncryptedVal);
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- pi = generate_proof_of_correct_sum(currEncryptedVal, retval);
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+ pi = generate_proof_of_correct_sum(currEncryptedVal, retval);
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return retval;
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}
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-void PrsonaServer::export_updates(std::vector<TwistBipoint>& otherPreviousVoteTally,
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- std::vector<Curvepoint>& otherCurrentPseudonyms, std::vector<std::vector<CurveBipoint>>& otherVoteMatrix) const
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-{
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- otherPreviousVoteTally = previousVoteTally;
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- otherCurrentPseudonyms = currentPseudonyms;
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- otherVoteMatrix = voteMatrix;
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-}
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+/*
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+ * EPOCH ROUNDS
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+ */
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-void PrsonaServer::import_updates(const Proof& pi, const std::vector<TwistBipoint>& otherPreviousVoteTally,
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- const std::vector<Curvepoint>& otherCurrentPseudonyms, const std::vector<std::vector<CurveBipoint>>& otherVoteMatrix)
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-{
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- if (!verify_update_proof(pi, otherPreviousVoteTally, otherCurrentPseudonyms, otherVoteMatrix))
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- {
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- std::cerr << "Could not verify valid update." << std::endl;
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- return;
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- }
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-
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- previousVoteTally = otherPreviousVoteTally;
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- currentPseudonyms = otherCurrentPseudonyms;
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- voteMatrix = otherVoteMatrix;
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-}
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-
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-void PrsonaServer::epoch_part_one(Proof& pi, Curvepoint& nextGenerator, std::vector<Scalar>& decryptedTallies, std::vector<Scalar>& encryptedTallyMasks)
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+// The first round, going from A_0 to A_0.5
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+void PrsonaServer::build_up_midway_pseudonyms(
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+ Proof& pi, Curvepoint& nextGenerator)
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{
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nextSeed.set_random();
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nextGenerator = nextGenerator * nextSeed;
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- for (size_t i = 0; i < currentPseudonyms.size(); i++)
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- {
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- Scalar currMask;
|
|
|
- currMask.set_random();
|
|
|
+ currentUserEncryptedTallies.clear();
|
|
|
+ currentTallyProofs.clear();
|
|
|
|
|
|
- encryptedTallyMasks[i] = encryptedTallyMasks[i].curveAdd(currMask);
|
|
|
+ for (size_t i = 0; i < currentPseudonyms.size(); i++)
|
|
|
currentPseudonyms[i] = currentPseudonyms[i] * nextSeed;
|
|
|
- }
|
|
|
-
|
|
|
- std::vector<size_t> shuffleOrder = order_data();
|
|
|
- rerandomize_vote_matrix();
|
|
|
-
|
|
|
- std::vector<Scalar> reorderedTallies;
|
|
|
- for (size_t i = 0; i < shuffleOrder.size(); i++)
|
|
|
- reorderedTallies.push_back(decryptedTallies[shuffleOrder[i]]);
|
|
|
- decryptedTallies = reorderedTallies;
|
|
|
|
|
|
- pi = generate_proof_of_shuffle(shuffleOrder);
|
|
|
+ rerandomize_data();
|
|
|
+ order_data(pi);
|
|
|
}
|
|
|
|
|
|
-void PrsonaServer::epoch_part_two(Proof& pi, const Curvepoint& nextGenerator, std::vector<EGCiphertext>& encryptedTallies, std::vector<Scalar>& encryptedTallyMasks)
|
|
|
+// In between these rounds, scores are tallied, decrypted,
|
|
|
+// and encrypted to fresh user pseudonyms (possible through weird math)
|
|
|
+
|
|
|
+// The second round, going from A_0.5 to A_1
|
|
|
+void PrsonaServer::break_down_midway_pseudonyms(
|
|
|
+ Proof& pi, const Curvepoint& nextGenerator)
|
|
|
{
|
|
|
Scalar inverseSeed = currentSeed.curveInverse();
|
|
|
|
|
|
for (size_t i = 0; i < currentPseudonyms.size(); i++)
|
|
|
{
|
|
|
- Scalar rerandomizer;
|
|
|
- rerandomizer.set_random();
|
|
|
-
|
|
|
currentPseudonyms[i] = currentPseudonyms[i] * inverseSeed;
|
|
|
- encryptedTallies[i].mask = encryptedTallies[i].mask * inverseSeed;
|
|
|
-
|
|
|
- encryptedTallies[i].mask = encryptedTallies[i].mask + currentPseudonyms[i] * rerandomizer;
|
|
|
- encryptedTallies[i].encryptedMessage = encryptedTallies[i].encryptedMessage + nextGenerator * rerandomizer;
|
|
|
-
|
|
|
- encryptedTallyMasks[i] = encryptedTallyMasks[i].curveAdd(rerandomizer);
|
|
|
+ currentUserEncryptedTallies[i].mask =
|
|
|
+ currentUserEncryptedTallies[i].mask * inverseSeed;
|
|
|
}
|
|
|
|
|
|
- std::vector<size_t> shuffleOrder = order_data();
|
|
|
- rerandomize_vote_matrix();
|
|
|
+ currentSeed = nextSeed;
|
|
|
+ currentFreshGenerator = nextGenerator;
|
|
|
+
|
|
|
+ rerandomize_data();
|
|
|
+ order_data(pi);
|
|
|
+}
|
|
|
|
|
|
- std::vector<Scalar> reorderedMasks;
|
|
|
- std::vector<EGCiphertext> reorderedTallies;
|
|
|
- for (size_t i = 0; i < shuffleOrder.size(); i++)
|
|
|
+/*
|
|
|
+ * DATA MAINTENANCE
|
|
|
+ */
|
|
|
+
|
|
|
+void PrsonaServer::import_updates(
|
|
|
+ const Proof& pi,
|
|
|
+ const std::vector<TwistBipoint>& otherPreviousVoteTallies,
|
|
|
+ const std::vector<Curvepoint>& otherCurrentPseudonyms,
|
|
|
+ const std::vector<EGCiphertext>& otherCurrentUserEncryptedTallies,
|
|
|
+ const std::vector<Proof>& otherCurrentTallyProofs,
|
|
|
+ const std::vector<std::vector<CurveBipoint>>& otherVoteMatrix)
|
|
|
+{
|
|
|
+ if (!verify_update_proof(pi))
|
|
|
{
|
|
|
- reorderedMasks.push_back(encryptedTallyMasks[shuffleOrder[i]]);
|
|
|
- reorderedTallies.push_back(encryptedTallies[shuffleOrder[i]]);
|
|
|
+ std::cerr << "Could not verify valid update." << std::endl;
|
|
|
+ return;
|
|
|
}
|
|
|
- encryptedTallyMasks = reorderedMasks;
|
|
|
- encryptedTallies = reorderedTallies;
|
|
|
|
|
|
- pi = generate_proof_of_shuffle(shuffleOrder);
|
|
|
+ previousVoteTallies = otherPreviousVoteTallies;
|
|
|
+ currentPseudonyms = otherCurrentPseudonyms;
|
|
|
+ currentUserEncryptedTallies = otherCurrentUserEncryptedTallies;
|
|
|
+ currentTallyProofs = otherCurrentTallyProofs;
|
|
|
+ voteMatrix = otherVoteMatrix;
|
|
|
+}
|
|
|
|
|
|
- currentSeed = nextSeed;
|
|
|
+void PrsonaServer::export_updates(
|
|
|
+ std::vector<TwistBipoint>& otherPreviousVoteTallies,
|
|
|
+ std::vector<Curvepoint>& otherCurrentPseudonyms,
|
|
|
+ std::vector<EGCiphertext>& otherCurrentUserEncryptedTallies,
|
|
|
+ std::vector<Proof>& otherCurrentTallyProofs,
|
|
|
+ std::vector<std::vector<CurveBipoint>>& otherVoteMatrix) const
|
|
|
+{
|
|
|
+ otherPreviousVoteTallies = previousVoteTallies;
|
|
|
+ otherCurrentPseudonyms = currentPseudonyms;
|
|
|
+ otherCurrentUserEncryptedTallies = currentUserEncryptedTallies;
|
|
|
+ otherCurrentTallyProofs = currentTallyProofs;
|
|
|
+ otherVoteMatrix = voteMatrix;
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+ * DATA SAFEKEEPING
|
|
|
+ */
|
|
|
+
|
|
|
+// Everything needs to be rerandomized during epoch rounds
|
|
|
+// NOTE: this may need to add something about proofs later?
|
|
|
+void PrsonaServer::rerandomize_data()
|
|
|
+{
|
|
|
+ for (size_t i = 0; i < voteMatrix.size(); i++)
|
|
|
+ {
|
|
|
+ for (size_t j = 0; j < voteMatrix[0].size(); j++)
|
|
|
+ voteMatrix[i][j] = bgn_system.rerandomize(voteMatrix[i][j]);
|
|
|
+
|
|
|
+ bgn_system.rerandomize(previousVoteTallies[i]);
|
|
|
+ if (!currentUserEncryptedTallies.empty())
|
|
|
+ {
|
|
|
+ Scalar rerandomizer;
|
|
|
+ rerandomizer.set_random();
|
|
|
+
|
|
|
+ currentUserEncryptedTallies[i].mask =
|
|
|
+ currentUserEncryptedTallies[i].mask +
|
|
|
+ currentPseudonyms[i] * rerandomizer;
|
|
|
+ currentUserEncryptedTallies[i].encryptedMessage =
|
|
|
+ currentUserEncryptedTallies[i].encryptedMessage +
|
|
|
+ currentFreshGenerator * rerandomizer;
|
|
|
+ }
|
|
|
+ }
|
|
|
}
|
|
|
|
|
|
-std::vector<size_t> PrsonaServer::order_data()
|
|
|
+/* This is what powers the "shuffle"; really, as pseudonyms get updated,
|
|
|
+ * the pseudonyms are no longer in the order prescribed by operator<().
|
|
|
+ * So, we put them (and everything else) back into that order,
|
|
|
+ * effectively shuffling them (and making lookups easier later on). */
|
|
|
+std::vector<size_t> PrsonaServer::order_data(Proof& pi)
|
|
|
{
|
|
|
std::vector<size_t> retval;
|
|
|
+
|
|
|
+ // SortingType's index member allows us to replicate the "sort" across
|
|
|
std::vector<SortingType> sortTracker;
|
|
|
for (size_t i = 0; i < currentPseudonyms.size(); i++)
|
|
|
{
|
|
|
@@ -265,46 +432,59 @@ std::vector<size_t> PrsonaServer::order_data()
|
|
|
|
|
|
sortTracker.push_back(curr);
|
|
|
}
|
|
|
-
|
|
|
std::sort(sortTracker.begin(), sortTracker.end());
|
|
|
|
|
|
+ // Order all other data in the same way, for consistency
|
|
|
std::vector<Curvepoint> newPseudonyms;
|
|
|
std::vector<TwistBipoint> newVoteTallies;
|
|
|
+ std::vector<EGCiphertext> newUserEncryptedTallies;
|
|
|
+ std::vector<Proof> newTallyProofs;
|
|
|
std::vector<std::vector<CurveBipoint>> newVoteMatrix;
|
|
|
|
|
|
for (size_t i = 0; i < sortTracker.size(); i++)
|
|
|
{
|
|
|
newPseudonyms.push_back(sortTracker[i].pseudonym);
|
|
|
- newVoteTallies.push_back(previousVoteTally[sortTracker[i].index]);
|
|
|
+ newVoteTallies.push_back(previousVoteTallies[sortTracker[i].index]);
|
|
|
+
|
|
|
+ if (!currentUserEncryptedTallies.empty())
|
|
|
+ {
|
|
|
+ newUserEncryptedTallies.push_back(
|
|
|
+ currentUserEncryptedTallies[sortTracker[i].index]);
|
|
|
+ }
|
|
|
+ if (!currentTallyProofs.empty())
|
|
|
+ {
|
|
|
+ newTallyProofs.push_back(
|
|
|
+ currentTallyProofs[sortTracker[i].index]);
|
|
|
+ }
|
|
|
|
|
|
std::vector<CurveBipoint> currNewRow;
|
|
|
for (size_t j = 0; j < currentPseudonyms.size(); j++)
|
|
|
{
|
|
|
- currNewRow.push_back(voteMatrix[sortTracker[i].index][sortTracker[j].index]);
|
|
|
+ currNewRow.push_back(
|
|
|
+ voteMatrix[sortTracker[i].index][sortTracker[j].index]);
|
|
|
}
|
|
|
newVoteMatrix.push_back(currNewRow);
|
|
|
|
|
|
retval.push_back(sortTracker[i].index);
|
|
|
}
|
|
|
|
|
|
+ previousVoteTallies = newVoteTallies;
|
|
|
currentPseudonyms = newPseudonyms;
|
|
|
- previousVoteTally = newVoteTallies;
|
|
|
+ currentUserEncryptedTallies = newUserEncryptedTallies;
|
|
|
+ currentTallyProofs = newTallyProofs;
|
|
|
voteMatrix = newVoteMatrix;
|
|
|
|
|
|
+ pi = generate_proof_of_shuffle(retval);
|
|
|
return retval;
|
|
|
}
|
|
|
|
|
|
-void PrsonaServer::rerandomize_vote_matrix()
|
|
|
-{
|
|
|
- for (size_t i = 0; i < voteMatrix.size(); i++)
|
|
|
- {
|
|
|
- for (size_t j = 0; j < voteMatrix[0].size(); j++)
|
|
|
- {
|
|
|
- voteMatrix[i][j] = bgn_system.rerandomize(voteMatrix[i][j]);
|
|
|
- }
|
|
|
- }
|
|
|
-}
|
|
|
+/*
|
|
|
+ * BINARY SEARCH
|
|
|
+ */
|
|
|
|
|
|
+/* Completely normal binary search
|
|
|
+ * There might be a standard function for this in <algorithms>?
|
|
|
+ * But it returns an iterator, not a size_t, so less useful. */
|
|
|
size_t PrsonaServer::binary_search(const Curvepoint& index) const
|
|
|
{
|
|
|
size_t lo, hi;
|
|
|
@@ -324,35 +504,65 @@ size_t PrsonaServer::binary_search(const Curvepoint& index) const
|
|
|
return lo;
|
|
|
}
|
|
|
|
|
|
-bool PrsonaServer::verify_valid_key_proof(const Proof& pi, const Curvepoint& shortTermPublicKey) const
|
|
|
+/*
|
|
|
+ * PROOF VERIFICATION
|
|
|
+ */
|
|
|
+
|
|
|
+bool PrsonaServer::verify_valid_key_proof(
|
|
|
+ const Proof& pi,
|
|
|
+ const Curvepoint& shortTermPublicKey) const
|
|
|
{
|
|
|
- if (!malicious_client)
|
|
|
+ if (!CLIENT_IS_MALICIOUS)
|
|
|
return pi.basic == "PROOF";
|
|
|
|
|
|
return pi.basic == "PROOF";
|
|
|
}
|
|
|
|
|
|
-bool PrsonaServer::verify_vote_proof(const Proof& pi, const std::vector<CurveBipoint>& votes, const Curvepoint& shortTermPublicKey) const
|
|
|
+bool PrsonaServer::verify_vote_proof(
|
|
|
+ const Proof& pi,
|
|
|
+ const std::vector<CurveBipoint>& votes,
|
|
|
+ const Curvepoint& shortTermPublicKey) const
|
|
|
{
|
|
|
- if (!malicious_client)
|
|
|
+ if (!CLIENT_IS_MALICIOUS)
|
|
|
return pi.basic == "PROOF";
|
|
|
|
|
|
return pi.basic == "PROOF";
|
|
|
}
|
|
|
|
|
|
-bool PrsonaServer::verify_update_proof(const Proof& pi, const std::vector<TwistBipoint>& otherPreviousVoteTally, const std::vector<Curvepoint>& otherCurrentPseudonyms, const std::vector<std::vector<CurveBipoint>>& otherVoteMatrix) const
|
|
|
+bool PrsonaServer::verify_update_proof(
|
|
|
+ const Proof& pi) const
|
|
|
{
|
|
|
- if (!malicious_server)
|
|
|
+ if (!SERVER_IS_MALICIOUS)
|
|
|
return pi.basic == "PROOF";
|
|
|
|
|
|
return pi.basic == "PROOF";
|
|
|
}
|
|
|
|
|
|
-Proof PrsonaServer::generate_valid_fresh_generator_proof(const Proof& oldProof) const
|
|
|
+/*
|
|
|
+ * PROOF GENERATION
|
|
|
+ */
|
|
|
+
|
|
|
+Proof PrsonaServer::generate_valid_default_tally_proof(
|
|
|
+ const EGCiphertext& newUserEncryptedTally, const Scalar& mask) const
|
|
|
+{
|
|
|
+ Proof retval;
|
|
|
+
|
|
|
+ if (!SERVER_IS_MALICIOUS)
|
|
|
+ {
|
|
|
+ retval.basic = "PROOF";
|
|
|
+ return retval;
|
|
|
+ }
|
|
|
+
|
|
|
+ retval.basic = "PROOF";
|
|
|
+ return retval;
|
|
|
+}
|
|
|
+
|
|
|
+Proof PrsonaServer::generate_valid_fresh_generator_proof(
|
|
|
+ const Proof& oldProof) const
|
|
|
{
|
|
|
Proof retval;
|
|
|
|
|
|
- if (!malicious_server)
|
|
|
+ if (!SERVER_IS_MALICIOUS)
|
|
|
{
|
|
|
retval.basic = "PROOF";
|
|
|
return retval;
|
|
|
@@ -362,11 +572,12 @@ Proof PrsonaServer::generate_valid_fresh_generator_proof(const Proof& oldProof)
|
|
|
return retval;
|
|
|
}
|
|
|
|
|
|
-Proof PrsonaServer::generate_votes_valid_proof(const std::vector<CurveBipoint>& votes, const Curvepoint& voter) const
|
|
|
+Proof PrsonaServer::generate_votes_valid_proof(
|
|
|
+ const std::vector<CurveBipoint>& votes, const Curvepoint& voter) const
|
|
|
{
|
|
|
Proof retval;
|
|
|
|
|
|
- if (!malicious_server)
|
|
|
+ if (!SERVER_IS_MALICIOUS)
|
|
|
{
|
|
|
retval.basic = "PROOF";
|
|
|
return retval;
|
|
|
@@ -376,11 +587,12 @@ Proof PrsonaServer::generate_votes_valid_proof(const std::vector<CurveBipoint>&
|
|
|
return retval;
|
|
|
}
|
|
|
|
|
|
-Proof PrsonaServer::generate_proof_of_added_user(const Curvepoint& shortTermPublicKey) const
|
|
|
+Proof PrsonaServer::generate_proof_of_added_user(
|
|
|
+ const Curvepoint& shortTermPublicKey) const
|
|
|
{
|
|
|
Proof retval;
|
|
|
|
|
|
- if (!malicious_server)
|
|
|
+ if (!SERVER_IS_MALICIOUS)
|
|
|
{
|
|
|
retval.basic = "PROOF";
|
|
|
return retval;
|
|
|
@@ -394,7 +606,7 @@ Proof PrsonaServer::generate_score_proof(const EGCiphertext& score) const
|
|
|
{
|
|
|
Proof retval;
|
|
|
|
|
|
- if (!malicious_server)
|
|
|
+ if (!SERVER_IS_MALICIOUS)
|
|
|
{
|
|
|
retval.basic = "PROOF";
|
|
|
return retval;
|
|
|
@@ -404,11 +616,13 @@ Proof PrsonaServer::generate_score_proof(const EGCiphertext& score) const
|
|
|
return retval;
|
|
|
}
|
|
|
|
|
|
-Proof PrsonaServer::generate_proof_of_correct_tally(const std::vector<Quadripoint>& BGNEncryptedTallies, const std::vector<Scalar>& decryptedTallies) const
|
|
|
+Proof PrsonaServer::generate_proof_of_correct_tally(
|
|
|
+ const Quadripoint& BGNEncryptedTally,
|
|
|
+ const Scalar& decryptedTally) const
|
|
|
{
|
|
|
Proof retval;
|
|
|
|
|
|
- if (!malicious_server)
|
|
|
+ if (!SERVER_IS_MALICIOUS)
|
|
|
{
|
|
|
retval.basic = "PROOF";
|
|
|
return retval;
|
|
|
@@ -418,11 +632,12 @@ Proof PrsonaServer::generate_proof_of_correct_tally(const std::vector<Quadripoin
|
|
|
return retval;
|
|
|
}
|
|
|
|
|
|
-Proof PrsonaServer::generate_proof_of_correct_sum(const TwistBipoint& BGNEncryptedSum, const Scalar& decryptedSum) const
|
|
|
+Proof PrsonaServer::generate_proof_of_correct_sum(
|
|
|
+ const TwistBipoint& BGNEncryptedSum, const Scalar& decryptedSum) const
|
|
|
{
|
|
|
Proof retval;
|
|
|
|
|
|
- if (!malicious_server)
|
|
|
+ if (!SERVER_IS_MALICIOUS)
|
|
|
{
|
|
|
retval.basic = "PROOF";
|
|
|
return retval;
|
|
|
@@ -432,11 +647,12 @@ Proof PrsonaServer::generate_proof_of_correct_sum(const TwistBipoint& BGNEncrypt
|
|
|
return retval;
|
|
|
}
|
|
|
|
|
|
-Proof PrsonaServer::generate_proof_of_shuffle(const std::vector<size_t>& shuffle_order) const
|
|
|
+Proof PrsonaServer::generate_proof_of_shuffle(
|
|
|
+ const std::vector<size_t>& shuffle_order) const
|
|
|
{
|
|
|
Proof retval;
|
|
|
|
|
|
- if (!malicious_server)
|
|
|
+ if (!SERVER_IS_MALICIOUS)
|
|
|
{
|
|
|
retval.basic = "PROOF";
|
|
|
return retval;
|
tristangurtler