void poly_eval_poly_polymod_coeffmod(const BigPoly &poly_to_evaluate, const BigPoly &poly_to_evaluate_at, const BigPoly &poly_modulus, const BigUInt &coeff_modulus, BigPoly &destination, const MemoryPoolHandle &pool) { if (!pool) { throw invalid_argument("pool is uninitialized"); } if (poly_to_evaluate.significant_coeff_count() > poly_modulus.coeff_count() || poly_to_evaluate.significant_coeff_bit_count() > coeff_modulus.significant_bit_count()) { throw invalid_argument("poly_to_evaluate is not reduced"); } if (poly_to_evaluate_at.significant_coeff_count() > poly_modulus.coeff_count() || poly_to_evaluate_at.significant_coeff_bit_count() > coeff_modulus.significant_bit_count()) { throw invalid_argument("poly_to_evaluate_at is not reduced"); } int poly_to_eval_coeff_uint64_count = poly_to_evaluate.coeff_uint64_count(); int coeff_modulus_bit_count = coeff_modulus.significant_bit_count(); if (poly_to_evaluate.is_zero()) { destination.set_zero(); } if (poly_to_evaluate_at.is_zero()) { destination.resize(1, coeff_modulus_bit_count); modulo_uint(poly_to_evaluate.data(), poly_to_eval_coeff_uint64_count, Modulus(coeff_modulus.data(), coeff_modulus.uint64_count(), pool), destination.data(), pool); return; } ConstPointer poly_to_eval_ptr = duplicate_poly_if_needed(poly_to_evaluate, poly_modulus.coeff_count(), coeff_modulus.uint64_count(), false, pool); ConstPointer poly_to_eval_at_ptr = duplicate_poly_if_needed(poly_to_evaluate_at, poly_modulus.coeff_count(), coeff_modulus.uint64_count(), false, pool); destination.resize(poly_modulus.coeff_count(), coeff_modulus_bit_count); util::poly_eval_poly_polymod_coeffmod(poly_to_eval_ptr.get(), poly_to_eval_at_ptr.get(), PolyModulus(poly_modulus.data(), poly_modulus.coeff_count(), poly_modulus.coeff_uint64_count()), Modulus(coeff_modulus.data(), coeff_modulus.uint64_count(), pool), destination.data(), pool); }
void exponentiate_poly_polymod_coeffmod(const BigPoly &operand, const BigUInt &exponent, const BigPoly &poly_modulus, const BigUInt &coeff_modulus, BigPoly &destination, const MemoryPoolHandle &pool) { if (operand.significant_coeff_count() > poly_modulus.coeff_count() || operand.significant_coeff_bit_count() > coeff_modulus.significant_bit_count()) { throw invalid_argument("operand is not reduced"); } if (exponent < 0) { throw invalid_argument("exponent must be a non-negative integer"); } if (operand.is_zero() && exponent == 0) { throw invalid_argument("undefined operation"); } if (!pool) { throw invalid_argument("pool is uninitialized"); } if (operand.is_zero()) { destination.set_zero(); return; } if (destination.coeff_bit_count() != coeff_modulus.significant_bit_count() || destination.coeff_count() != poly_modulus.coeff_count()) { destination.resize(poly_modulus.coeff_count(), coeff_modulus.significant_bit_count()); } ConstPointer operand_ptr = duplicate_poly_if_needed(operand, poly_modulus.coeff_count(), coeff_modulus.uint64_count(), false, pool); util::exponentiate_poly_polymod_coeffmod(operand_ptr.get(), exponent.data(), exponent.uint64_count(), PolyModulus(poly_modulus.data(), poly_modulus.coeff_count(), poly_modulus.coeff_uint64_count()), Modulus(coeff_modulus.data(), coeff_modulus.uint64_count(), pool), destination.data(), pool); }
KeyGenerator::KeyGenerator(const EncryptionParameters &parms) : poly_modulus_(parms.poly_modulus()), coeff_modulus_(parms.coeff_modulus()), plain_modulus_(parms.plain_modulus()), noise_standard_deviation_(parms.noise_standard_deviation()), noise_max_deviation_(parms.noise_max_deviation()), decomposition_bit_count_(parms.decomposition_bit_count()), mode_(parms.mode()), random_generator_(parms.random_generator() != nullptr ? parms.random_generator()->create() : UniformRandomGeneratorFactory::default_factory()->create()) { // Verify required parameters are non-zero and non-nullptr. if (poly_modulus_.is_zero()) { throw invalid_argument("poly_modulus cannot be zero"); } if (coeff_modulus_.is_zero()) { throw invalid_argument("coeff_modulus cannot be zero"); } if (plain_modulus_.is_zero()) { throw invalid_argument("plain_modulus cannot be zero"); } if (noise_standard_deviation_ < 0) { throw invalid_argument("noise_standard_deviation must be non-negative"); } if (noise_max_deviation_ < 0) { throw invalid_argument("noise_max_deviation must be non-negative"); } if (decomposition_bit_count_ <= 0) { throw invalid_argument("decomposition_bit_count must be positive"); } // Verify parameters. if (plain_modulus_ >= coeff_modulus_) { throw invalid_argument("plain_modulus must be smaller than coeff_modulus"); } if (!are_poly_coefficients_less_than(poly_modulus_, coeff_modulus_)) { throw invalid_argument("poly_modulus cannot have coefficients larger than coeff_modulus"); } // Resize encryption parameters to consistent size. int coeff_count = poly_modulus_.significant_coeff_count(); int coeff_bit_count = coeff_modulus_.significant_bit_count(); int coeff_uint64_count = divide_round_up(coeff_bit_count, bits_per_uint64); if (poly_modulus_.coeff_count() != coeff_count || poly_modulus_.coeff_bit_count() != coeff_bit_count) { poly_modulus_.resize(coeff_count, coeff_bit_count); } if (coeff_modulus_.bit_count() != coeff_bit_count) { coeff_modulus_.resize(coeff_bit_count); } if (plain_modulus_.bit_count() != coeff_bit_count) { plain_modulus_.resize(coeff_bit_count); } if (decomposition_bit_count_ > coeff_bit_count) { decomposition_bit_count_ = coeff_bit_count; } // Calculate -1 (mod coeff_modulus). coeff_modulus_minus_one_.resize(coeff_bit_count); decrement_uint(coeff_modulus_.pointer(), coeff_uint64_count, coeff_modulus_minus_one_.pointer()); // Initialize public and secret key. public_key_.resize(coeff_count, coeff_bit_count); secret_key_.resize(coeff_count, coeff_bit_count); // Initialize evaluation keys. int evaluation_key_count = 0; Pointer evaluation_factor(allocate_uint(coeff_uint64_count, pool_)); set_uint(1, coeff_uint64_count, evaluation_factor.get()); while (!is_zero_uint(evaluation_factor.get(), coeff_uint64_count) && is_less_than_uint_uint(evaluation_factor.get(), coeff_modulus_.pointer(), coeff_uint64_count)) { left_shift_uint(evaluation_factor.get(), decomposition_bit_count_, coeff_uint64_count, evaluation_factor.get()); evaluation_key_count++; } evaluation_keys_.resize(evaluation_key_count); for (int i = 0; i < evaluation_key_count; ++i) { evaluation_keys_[i].resize(coeff_count, coeff_bit_count); } // Initialize moduli. polymod_ = PolyModulus(poly_modulus_.pointer(), coeff_count, coeff_uint64_count); mod_ = Modulus(coeff_modulus_.pointer(), coeff_uint64_count, pool_); }
HkeyGen::HkeyGen(const EncryptionParameters &parms, const BigPoly &secret_key) : poly_modulus_(parms.poly_modulus()), coeff_modulus_(parms.coeff_modulus()), plain_modulus_(parms.plain_modulus()), secret_key_(secret_key), orig_plain_modulus_bit_count_(parms.plain_modulus().significant_bit_count()) { // Verify required parameters are non-zero and non-nullptr. if (poly_modulus_.is_zero()) { throw invalid_argument("poly_modulus cannot be zero"); } if (coeff_modulus_.is_zero()) { throw invalid_argument("coeff_modulus cannot be zero"); } if (plain_modulus_.is_zero()) { throw invalid_argument("plain_modulus cannot be zero"); } if (secret_key_.is_zero()) { throw invalid_argument("secret_key cannot be zero"); } // Verify parameters. if (plain_modulus_ >= coeff_modulus_) { throw invalid_argument("plain_modulus must be smaller than coeff_modulus"); } if (!are_poly_coefficients_less_than(poly_modulus_, coeff_modulus_)) { throw invalid_argument("poly_modulus cannot have coefficients larger than coeff_modulus"); } // Resize encryption parameters to consistent size. int coeff_count = poly_modulus_.significant_coeff_count(); int coeff_bit_count = coeff_modulus_.significant_bit_count(); int coeff_uint64_count = divide_round_up(coeff_bit_count, bits_per_uint64); if (poly_modulus_.coeff_count() != coeff_count || poly_modulus_.coeff_bit_count() != coeff_bit_count) { poly_modulus_.resize(coeff_count, coeff_bit_count); } if (coeff_modulus_.bit_count() != coeff_bit_count) { coeff_modulus_.resize(coeff_bit_count); } if (plain_modulus_.bit_count() != coeff_bit_count) { plain_modulus_.resize(coeff_bit_count); } if (secret_key_.coeff_count() != coeff_count || secret_key_.coeff_bit_count() != coeff_bit_count || secret_key_.significant_coeff_count() == coeff_count || !are_poly_coefficients_less_than(secret_key_, coeff_modulus_)) { throw invalid_argument("secret_key is not valid for encryption parameters"); } // Set the secret_key_array to have size 1 (first power of secret) secret_key_array_.resize(1, coeff_count, coeff_bit_count); set_poly_poly(secret_key_.pointer(), coeff_count, coeff_uint64_count, secret_key_array_.pointer(0)); MemoryPool &pool = *MemoryPool::default_pool(); // Calculate coeff_modulus / plain_modulus. coeff_div_plain_modulus_.resize(coeff_bit_count); Pointer temp(allocate_uint(coeff_uint64_count, pool)); divide_uint_uint(coeff_modulus_.pointer(), plain_modulus_.pointer(), coeff_uint64_count, coeff_div_plain_modulus_.pointer(), temp.get(), pool); // Calculate coeff_modulus / plain_modulus / 2. coeff_div_plain_modulus_div_two_.resize(coeff_bit_count); right_shift_uint(coeff_div_plain_modulus_.pointer(), 1, coeff_uint64_count, coeff_div_plain_modulus_div_two_.pointer()); // Calculate coeff_modulus / 2. upper_half_threshold_.resize(coeff_bit_count); half_round_up_uint(coeff_modulus_.pointer(), coeff_uint64_count, upper_half_threshold_.pointer()); // Calculate upper_half_increment. upper_half_increment_.resize(coeff_bit_count); multiply_truncate_uint_uint(plain_modulus_.pointer(), coeff_div_plain_modulus_.pointer(), coeff_uint64_count, upper_half_increment_.pointer()); sub_uint_uint(coeff_modulus_.pointer(), upper_half_increment_.pointer(), coeff_uint64_count, upper_half_increment_.pointer()); // Initialize moduli. polymod_ = PolyModulus(poly_modulus_.pointer(), coeff_count, coeff_uint64_count); mod_ = Modulus(coeff_modulus_.pointer(), coeff_uint64_count, pool); }
Evaluator::Evaluator(const EncryptionParameters &parms, const EvaluationKeys &evaluation_keys) : poly_modulus_(parms.poly_modulus()), coeff_modulus_(parms.coeff_modulus()), plain_modulus_(parms.plain_modulus()), decomposition_bit_count_(parms.decomposition_bit_count()), evaluation_keys_(evaluation_keys), mode_(parms.mode()) { // Verify required parameters are non-zero and non-nullptr. if (poly_modulus_.is_zero()) { throw invalid_argument("poly_modulus cannot be zero"); } if (coeff_modulus_.is_zero()) { throw invalid_argument("coeff_modulus cannot be zero"); } if (plain_modulus_.is_zero()) { throw invalid_argument("plain_modulus cannot be zero"); } if (decomposition_bit_count_ <= 0) { throw invalid_argument("decomposition_bit_count must be positive"); } if (evaluation_keys_.count() == 0) { throw invalid_argument("evaluation_keys cannot be empty"); } // Verify parameters. if (plain_modulus_ >= coeff_modulus_) { throw invalid_argument("plain_modulus must be smaller than coeff_modulus"); } if (!are_poly_coefficients_less_than(poly_modulus_, coeff_modulus_)) { throw invalid_argument("poly_modulus cannot have coefficients larger than coeff_modulus"); } // Resize encryption parameters to consistent size. int coeff_count = poly_modulus_.significant_coeff_count(); int coeff_bit_count = coeff_modulus_.significant_bit_count(); int coeff_uint64_count = divide_round_up(coeff_bit_count, bits_per_uint64); if (poly_modulus_.coeff_count() != coeff_count || poly_modulus_.coeff_bit_count() != coeff_bit_count) { poly_modulus_.resize(coeff_count, coeff_bit_count); } if (coeff_modulus_.bit_count() != coeff_bit_count) { coeff_modulus_.resize(coeff_bit_count); } if (plain_modulus_.bit_count() != coeff_bit_count) { plain_modulus_.resize(coeff_bit_count); } if (decomposition_bit_count_ > coeff_bit_count) { decomposition_bit_count_ = coeff_bit_count; } // Determine correct number of evaluation keys. int evaluation_key_count = 0; Pointer evaluation_factor(allocate_uint(coeff_uint64_count, pool_)); set_uint(1, coeff_uint64_count, evaluation_factor.get()); while (!is_zero_uint(evaluation_factor.get(), coeff_uint64_count) && is_less_than_uint_uint(evaluation_factor.get(), coeff_modulus_.pointer(), coeff_uint64_count)) { left_shift_uint(evaluation_factor.get(), decomposition_bit_count_, coeff_uint64_count, evaluation_factor.get()); evaluation_key_count++; } // Verify evaluation keys. if (evaluation_keys_.count() != evaluation_key_count) { throw invalid_argument("evaluation_keys is not valid for encryption parameters"); } for (int i = 0; i < evaluation_keys_.count(); ++i) { BigPoly &evaluation_key = evaluation_keys_[i]; if (evaluation_key.coeff_count() != coeff_count || evaluation_key.coeff_bit_count() != coeff_bit_count || evaluation_key.significant_coeff_count() == coeff_count || !are_poly_coefficients_less_than(evaluation_key, coeff_modulus_)) { throw invalid_argument("evaluation_keys is not valid for encryption parameters"); } } // Calculate coeff_modulus / plain_modulus. coeff_div_plain_modulus_.resize(coeff_bit_count); Pointer temp(allocate_uint(coeff_uint64_count, pool_)); divide_uint_uint(coeff_modulus_.pointer(), plain_modulus_.pointer(), coeff_uint64_count, coeff_div_plain_modulus_.pointer(), temp.get(), pool_); // Calculate (plain_modulus + 1) / 2. plain_upper_half_threshold_.resize(coeff_bit_count); half_round_up_uint(plain_modulus_.pointer(), coeff_uint64_count, plain_upper_half_threshold_.pointer()); // Calculate coeff_modulus - plain_modulus. plain_upper_half_increment_.resize(coeff_bit_count); sub_uint_uint(coeff_modulus_.pointer(), plain_modulus_.pointer(), coeff_uint64_count, plain_upper_half_increment_.pointer()); // Calculate (plain_modulus + 1) / 2 * coeff_div_plain_modulus. upper_half_threshold_.resize(coeff_bit_count); multiply_truncate_uint_uint(plain_upper_half_threshold_.pointer(), coeff_div_plain_modulus_.pointer(), coeff_uint64_count, upper_half_threshold_.pointer()); // Calculate upper_half_increment. upper_half_increment_.resize(coeff_bit_count); multiply_truncate_uint_uint(plain_modulus_.pointer(), coeff_div_plain_modulus_.pointer(), coeff_uint64_count, upper_half_increment_.pointer()); sub_uint_uint(coeff_modulus_.pointer(), upper_half_increment_.pointer(), coeff_uint64_count, upper_half_increment_.pointer()); // Widen coeff modulus. int product_coeff_bit_count = coeff_bit_count + coeff_bit_count + get_significant_bit_count(static_cast<uint64_t>(coeff_count)); int plain_modulus_bit_count = plain_modulus_.significant_bit_count(); int wide_bit_count = product_coeff_bit_count + plain_modulus_bit_count; int wide_uint64_count = divide_round_up(wide_bit_count, bits_per_uint64); wide_coeff_modulus_.resize(wide_bit_count); wide_coeff_modulus_ = coeff_modulus_; // Calculate wide_coeff_modulus_ / 2. wide_coeff_modulus_div_two_.resize(wide_bit_count); right_shift_uint(wide_coeff_modulus_.pointer(), 1, wide_uint64_count, wide_coeff_modulus_div_two_.pointer()); // Initialize moduli. polymod_ = PolyModulus(poly_modulus_.pointer(), coeff_count, coeff_uint64_count); if (mode_ == TEST_MODE) { mod_ = Modulus(plain_modulus_.pointer(), coeff_uint64_count, pool_); } else { mod_ = Modulus(coeff_modulus_.pointer(), coeff_uint64_count, pool_); } }