arnaucube
arnaucube/phantom-zonePublic Self-hosted repository
phantom-zone/src/bool/evaluator.rs
src/bool/evaluator.rsRaw
   1use std::{
   2    borrow::BorrowMut,
   3    cell::{OnceCell, RefCell},
   4    clone,
   5    collections::HashMap,
   6    fmt::{Debug, Display},
   7    iter::Once,
   8    marker::PhantomData,
   9    ops::Shr,
  10    sync::OnceLock,
  11};
  12
  13use itertools::{izip, partition, Itertools};
  14use num_traits::{FromPrimitive, Num, One, Pow, PrimInt, ToPrimitive, WrappingSub, Zero};
  15use rand_distr::uniform::SampleUniform;
  16
  17use crate::{
  18    backend::{ArithmeticOps, GetModulus, ModInit, ModularOpsU64, Modulus, VectorOps},
  19    decomposer::{Decomposer, DefaultDecomposer, NumInfo, RlweDecomposer},
  20    lwe::{decrypt_lwe, encrypt_lwe, lwe_key_switch, lwe_ksk_keygen, measure_noise_lwe, LweSecret},
  21    multi_party::public_key_share,
  22    ntt::{self, Ntt, NttBackendU64, NttInit},
  23    pbs::{pbs, sample_extract, PbsInfo, PbsKey},
  24    random::{
  25        DefaultSecureRng, NewWithSeed, RandomFill, RandomFillGaussianInModulus,
  26        RandomFillUniformInModulus, RandomGaussianElementInModulus,
  27    },
  28    rgsw::{
  29        decrypt_rlwe, galois_auto, galois_key_gen, generate_auto_map, public_key_encrypt_rgsw,
  30        rgsw_by_rgsw_inplace, rlwe_by_rgsw, secret_key_encrypt_rgsw, IsTrivial, RgswCiphertext,
  31        RlweCiphertext, RlweSecret,
  32    },
  33    utils::{
  34        fill_random_ternary_secret_with_hamming_weight, generate_prime, mod_exponent, Global,
  35        TryConvertFrom1, WithLocal,
  36    },
  37    Decryptor, Encryptor, Matrix, MatrixEntity, MatrixMut, MultiPartyDecryptor, Row, RowEntity,
  38    RowMut, Secret,
  39};
  40
  41use super::{
  42    keys::ClientKey,
  43    parameters::{BoolParameters, CiphertextModulus},
  44    CommonReferenceSeededCollectivePublicKeyShare, CommonReferenceSeededMultiPartyServerKeyShare,
  45    SeededMultiPartyServerKey, SeededServerKey, ServerKeyEvaluationDomain,
  46};
  47
  48pub struct MultiPartyCrs<S> {
  49    pub(super) seed: S,
  50}
  51
  52impl<S: Default + Copy> MultiPartyCrs<S> {
  53    /// Seed to generate public key share using MultiPartyCrs as the main seed.
  54    ///
  55    /// Public key seed equals the 1st seed extracted from PRNG Seeded with
  56    /// MiltiPartyCrs's seed.
  57    pub(super) fn public_key_share_seed<Rng: NewWithSeed<Seed = S> + RandomFill<S>>(&self) -> S {
  58        let mut prng = Rng::new_with_seed(self.seed);
  59
  60        let mut seed = S::default();
  61        RandomFill::<S>::random_fill(&mut prng, &mut seed);
  62        seed
  63    }
  64
  65    /// Seed to generate server key share using MultiPartyCrs as the main seed.
  66    ///
  67    /// Server key seed equals the 2nd seed extracted from PRNG Seeded with
  68    /// MiltiPartyCrs's seed.
  69    pub(super) fn server_key_share_seed<Rng: NewWithSeed<Seed = S> + RandomFill<S>>(&self) -> S {
  70        let mut prng = Rng::new_with_seed(self.seed);
  71
  72        let mut seed = S::default();
  73        RandomFill::<S>::random_fill(&mut prng, &mut seed);
  74        RandomFill::<S>::random_fill(&mut prng, &mut seed);
  75        seed
  76    }
  77}
  78
  79pub(crate) trait BooleanGates {
  80    type Ciphertext: RowEntity;
  81    type Key;
  82
  83    fn and_inplace(&mut self, c0: &mut Self::Ciphertext, c1: &Self::Ciphertext, key: &Self::Key);
  84    fn nand_inplace(&mut self, c0: &mut Self::Ciphertext, c1: &Self::Ciphertext, key: &Self::Key);
  85    fn or_inplace(&mut self, c0: &mut Self::Ciphertext, c1: &Self::Ciphertext, key: &Self::Key);
  86    fn nor_inplace(&mut self, c0: &mut Self::Ciphertext, c1: &Self::Ciphertext, key: &Self::Key);
  87    fn xor_inplace(&mut self, c0: &mut Self::Ciphertext, c1: &Self::Ciphertext, key: &Self::Key);
  88    fn xnor_inplace(&mut self, c0: &mut Self::Ciphertext, c1: &Self::Ciphertext, key: &Self::Key);
  89    fn not_inplace(&mut self, c: &mut Self::Ciphertext);
  90
  91    fn and(
  92        &mut self,
  93        c0: &Self::Ciphertext,
  94        c1: &Self::Ciphertext,
  95        key: &Self::Key,
  96    ) -> Self::Ciphertext;
  97    fn nand(
  98        &mut self,
  99        c0: &Self::Ciphertext,
 100        c1: &Self::Ciphertext,
 101        key: &Self::Key,
 102    ) -> Self::Ciphertext;
 103    fn or(
 104        &mut self,
 105        c0: &Self::Ciphertext,
 106        c1: &Self::Ciphertext,
 107        key: &Self::Key,
 108    ) -> Self::Ciphertext;
 109    fn nor(
 110        &mut self,
 111        c0: &Self::Ciphertext,
 112        c1: &Self::Ciphertext,
 113        key: &Self::Key,
 114    ) -> Self::Ciphertext;
 115    fn xor(
 116        &mut self,
 117        c0: &Self::Ciphertext,
 118        c1: &Self::Ciphertext,
 119        key: &Self::Key,
 120    ) -> Self::Ciphertext;
 121    fn xnor(
 122        &mut self,
 123        c0: &Self::Ciphertext,
 124        c1: &Self::Ciphertext,
 125        key: &Self::Key,
 126    ) -> Self::Ciphertext;
 127    fn not(&mut self, c: &Self::Ciphertext) -> Self::Ciphertext;
 128}
 129
 130struct ScratchMemory<M>
 131where
 132    M: Matrix,
 133{
 134    lwe_vector: M::R,
 135    decomposition_matrix: M,
 136}
 137
 138impl<M: MatrixEntity> ScratchMemory<M>
 139where
 140    M::R: RowEntity,
 141{
 142    fn new(parameters: &BoolParameters<M::MatElement>) -> Self {
 143        // Vector to store LWE ciphertext with LWE dimesnion n
 144        let lwe_vector = M::R::zeros(parameters.lwe_n().0 + 1);
 145
 146        // Matrix to store decomposed polynomials
 147        // Max decompistion count + space for temporary RLWE
 148        let d = std::cmp::max(
 149            parameters.auto_decomposition_count().0,
 150            std::cmp::max(
 151                parameters.rlwe_rgsw_decomposition_count().0 .0,
 152                parameters.rlwe_rgsw_decomposition_count().1 .0,
 153            ),
 154        ) + 2;
 155        let decomposition_matrix = M::zeros(d, parameters.rlwe_n().0);
 156
 157        Self {
 158            lwe_vector,
 159            decomposition_matrix,
 160        }
 161    }
 162}
 163
 164pub(super) trait BoolEncoding {
 165    type Element;
 166    fn true_el(&self) -> Self::Element;
 167    fn false_el(&self) -> Self::Element;
 168    fn qby4(&self) -> Self::Element;
 169    fn decode(&self, m: Self::Element) -> bool;
 170}
 171
 172impl<T> BoolEncoding for CiphertextModulus<T>
 173where
 174    CiphertextModulus<T>: Modulus<Element = T>,
 175    T: PrimInt,
 176{
 177    type Element = T;
 178
 179    fn qby4(&self) -> Self::Element {
 180        if self.is_native() {
 181            T::one() << (CiphertextModulus::<T>::_bits() - 2)
 182        } else {
 183            self.q().unwrap() >> 2
 184        }
 185    }
 186    /// Q/8
 187    fn true_el(&self) -> Self::Element {
 188        if self.is_native() {
 189            T::one() << (CiphertextModulus::<T>::_bits() - 3)
 190        } else {
 191            self.q().unwrap() >> 3
 192        }
 193    }
 194    /// -Q/8
 195    fn false_el(&self) -> Self::Element {
 196        self.largest_unsigned_value() - self.true_el() + T::one()
 197    }
 198    fn decode(&self, m: Self::Element) -> bool {
 199        let qby8 = self.true_el();
 200        let m = (((m + qby8).to_f64().unwrap() * 4.0f64) / self.q_as_f64().unwrap()).round()
 201            as usize
 202            % 4usize;
 203
 204        if m == 0 {
 205            return false;
 206        } else if m == 1 {
 207            return true;
 208        } else {
 209            panic!("Incorrect bool decryption. Got m={m} but expected m to be 0 or 1")
 210        }
 211    }
 212}
 213
 214pub(super) struct BoolPbsInfo<M: Matrix, Ntt, RlweModOp, LweModOp> {
 215    auto_decomposer: DefaultDecomposer<M::MatElement>,
 216    rlwe_rgsw_decomposer: (
 217        DefaultDecomposer<M::MatElement>,
 218        DefaultDecomposer<M::MatElement>,
 219    ),
 220    lwe_decomposer: DefaultDecomposer<M::MatElement>,
 221    g_k_dlog_map: Vec<usize>,
 222    rlwe_nttop: Ntt,
 223    rlwe_modop: RlweModOp,
 224    lwe_modop: LweModOp,
 225    embedding_factor: usize,
 226    rlwe_qby4: M::MatElement,
 227    rlwe_auto_maps: Vec<(Vec<usize>, Vec<bool>)>,
 228    parameters: BoolParameters<M::MatElement>,
 229}
 230
 231impl<M: Matrix, NttOp, RlweModOp, LweModOp> PbsInfo for BoolPbsInfo<M, NttOp, RlweModOp, LweModOp>
 232where
 233    M::MatElement: PrimInt + WrappingSub + NumInfo + FromPrimitive,
 234    RlweModOp: ArithmeticOps<Element = M::MatElement> + VectorOps<Element = M::MatElement>,
 235    LweModOp: ArithmeticOps<Element = M::MatElement> + VectorOps<Element = M::MatElement>,
 236    NttOp: Ntt<Element = M::MatElement>,
 237{
 238    type Modulus = CiphertextModulus<M::MatElement>;
 239    type Element = M::MatElement;
 240    type D = DefaultDecomposer<M::MatElement>;
 241    type RlweModOp = RlweModOp;
 242    type LweModOp = LweModOp;
 243    type NttOp = NttOp;
 244    fn rlwe_auto_map(&self, k: usize) -> &(Vec<usize>, Vec<bool>) {
 245        &self.rlwe_auto_maps[k]
 246    }
 247    fn br_q(&self) -> usize {
 248        *self.parameters.br_q()
 249    }
 250    fn lwe_decomposer(&self) -> &Self::D {
 251        &self.lwe_decomposer
 252    }
 253    fn rlwe_rgsw_decomposer(&self) -> &(Self::D, Self::D) {
 254        &self.rlwe_rgsw_decomposer
 255    }
 256    fn auto_decomposer(&self) -> &Self::D {
 257        &self.auto_decomposer
 258    }
 259    fn embedding_factor(&self) -> usize {
 260        self.embedding_factor
 261    }
 262    fn g(&self) -> isize {
 263        self.parameters.g() as isize
 264    }
 265    fn w(&self) -> usize {
 266        self.parameters.w()
 267    }
 268    fn g_k_dlog_map(&self) -> &[usize] {
 269        &self.g_k_dlog_map
 270    }
 271    fn lwe_n(&self) -> usize {
 272        self.parameters.lwe_n().0
 273    }
 274    fn lwe_q(&self) -> &Self::Modulus {
 275        self.parameters.lwe_q()
 276    }
 277    fn rlwe_n(&self) -> usize {
 278        self.parameters.rlwe_n().0
 279    }
 280    fn rlwe_q(&self) -> &Self::Modulus {
 281        self.parameters.rlwe_q()
 282    }
 283    fn modop_lweq(&self) -> &Self::LweModOp {
 284        &self.lwe_modop
 285    }
 286    fn modop_rlweq(&self) -> &Self::RlweModOp {
 287        &self.rlwe_modop
 288    }
 289    fn nttop_rlweq(&self) -> &Self::NttOp {
 290        &self.rlwe_nttop
 291    }
 292}
 293
 294pub(crate) struct BoolEvaluator<M, Ntt, RlweModOp, LweModOp>
 295where
 296    M: Matrix,
 297{
 298    pbs_info: BoolPbsInfo<M, Ntt, RlweModOp, LweModOp>,
 299    scratch_memory: ScratchMemory<M>,
 300    nand_test_vec: M::R,
 301    and_test_vec: M::R,
 302    or_test_vec: M::R,
 303    nor_test_vec: M::R,
 304    xor_test_vec: M::R,
 305    xnor_test_vec: M::R,
 306    _phantom: PhantomData<M>,
 307}
 308
 309impl<M: Matrix, NttOp, RlweModOp, LweModOp> BoolEvaluator<M, NttOp, RlweModOp, LweModOp> {
 310    pub(super) fn parameters(&self) -> &BoolParameters<M::MatElement> {
 311        &self.pbs_info.parameters
 312    }
 313
 314    pub(super) fn pbs_info(&self) -> &BoolPbsInfo<M, NttOp, RlweModOp, LweModOp> {
 315        &self.pbs_info
 316    }
 317}
 318
 319impl<M: Matrix, NttOp, RlweModOp, LweModOp> BoolEvaluator<M, NttOp, RlweModOp, LweModOp>
 320where
 321    M: MatrixEntity + MatrixMut,
 322    M::MatElement:
 323        PrimInt + Debug + Display + NumInfo + FromPrimitive + WrappingSub + SampleUniform,
 324    NttOp: Ntt<Element = M::MatElement>,
 325    RlweModOp: ArithmeticOps<Element = M::MatElement>
 326        + VectorOps<Element = M::MatElement>
 327        + GetModulus<Element = M::MatElement, M = CiphertextModulus<M::MatElement>>,
 328    LweModOp: ArithmeticOps<Element = M::MatElement>
 329        + VectorOps<Element = M::MatElement>
 330        + GetModulus<Element = M::MatElement, M = CiphertextModulus<M::MatElement>>,
 331    M::R: TryConvertFrom1<[i32], CiphertextModulus<M::MatElement>> + RowEntity + Debug,
 332    <M as Matrix>::R: RowMut,
 333{
 334    pub(super) fn new(parameters: BoolParameters<M::MatElement>) -> Self
 335    where
 336        RlweModOp: ModInit<M = CiphertextModulus<M::MatElement>>,
 337        LweModOp: ModInit<M = CiphertextModulus<M::MatElement>>,
 338        NttOp: NttInit<CiphertextModulus<M::MatElement>>,
 339    {
 340        //TODO(Jay): Run sanity checks for modulus values in parameters
 341
 342        // generates dlog map s.t. (+/-)g^{k} % q = a, for all a \in Z*_{q} and k \in
 343        // [0, q/4). We store the dlog `k` at index `a`. This makes it easier to
 344        // simply look up `k` at runtime as vec[a]. If a = g^{k} then dlog is
 345        // stored as k. If a = -g^{k} then dlog is stored as k = q/4. This is done to
 346        // differentiate sign.
 347        let g = parameters.g();
 348        let q = *parameters.br_q();
 349        let mut g_k_dlog_map = vec![0usize; q];
 350        for i in 0..q / 4 {
 351            let v = mod_exponent(g as u64, i as u64, q as u64) as usize;
 352            // g^i
 353            g_k_dlog_map[v] = i;
 354            // -(g^i)
 355            g_k_dlog_map[q - v] = i + (q / 4);
 356        }
 357
 358        let embedding_factor = (2 * parameters.rlwe_n().0) / q;
 359
 360        let rlwe_nttop = NttOp::new(parameters.rlwe_q(), parameters.rlwe_n().0);
 361        let rlwe_modop = RlweModOp::new(*parameters.rlwe_q());
 362        let lwe_modop = LweModOp::new(*parameters.lwe_q());
 363
 364        let q = *parameters.br_q();
 365        let qby2 = q >> 1;
 366        let qby8 = q >> 3;
 367        // Q/8 (Q: rlwe_q)
 368        let true_m_el = parameters.rlwe_q().true_el();
 369        // -Q/8
 370        let false_m_el = parameters.rlwe_q().false_el();
 371        let (auto_map_index, auto_map_sign) = generate_auto_map(qby2, -(g as isize));
 372
 373        let init_test_vec = |partition_el: usize,
 374                             before_partition_el: M::MatElement,
 375                             after_partition_el: M::MatElement| {
 376            let mut test_vec = M::R::zeros(qby2);
 377            for i in 0..qby2 {
 378                if i < partition_el {
 379                    test_vec.as_mut()[i] = before_partition_el;
 380                } else {
 381                    test_vec.as_mut()[i] = after_partition_el;
 382                }
 383            }
 384
 385            // v(X) -> v(X^{-g})
 386            let mut test_vec_autog = M::R::zeros(qby2);
 387            izip!(
 388                test_vec.as_ref().iter(),
 389                auto_map_index.iter(),
 390                auto_map_sign.iter()
 391            )
 392            .for_each(|(v, to_index, to_sign)| {
 393                if !to_sign {
 394                    // negate
 395                    test_vec_autog.as_mut()[*to_index] = rlwe_modop.neg(v);
 396                } else {
 397                    test_vec_autog.as_mut()[*to_index] = *v;
 398                }
 399            });
 400
 401            return test_vec_autog;
 402        };
 403
 404        let nand_test_vec = init_test_vec(3 * qby8, true_m_el, false_m_el);
 405        let and_test_vec = init_test_vec(3 * qby8, false_m_el, true_m_el);
 406        let or_test_vec = init_test_vec(qby8, false_m_el, true_m_el);
 407        let nor_test_vec = init_test_vec(qby8, true_m_el, false_m_el);
 408        let xor_test_vec = init_test_vec(qby8, false_m_el, true_m_el);
 409        let xnor_test_vec = init_test_vec(qby8, true_m_el, false_m_el);
 410
 411        // auto map indices and sign
 412        // Auto maps are stored as [-g, g^{1}, g^{2}, ..., g^{w}]
 413        let mut rlwe_auto_maps = vec![];
 414        let ring_size = parameters.rlwe_n().0;
 415        let g = parameters.g();
 416        let br_q = parameters.br_q();
 417        let auto_element_dlogs = parameters.auto_element_dlogs();
 418        assert!(auto_element_dlogs[0] == 0);
 419        for i in auto_element_dlogs.into_iter() {
 420            let el = if i == 0 {
 421                -(g as isize)
 422            } else {
 423                (g.pow(i as u32) % br_q) as isize
 424            };
 425            rlwe_auto_maps.push(generate_auto_map(ring_size, el))
 426        }
 427
 428        let rlwe_qby4 = parameters.rlwe_q().qby4();
 429
 430        let scratch_memory = ScratchMemory::new(&parameters);
 431
 432        let pbs_info = BoolPbsInfo {
 433            auto_decomposer: parameters.auto_decomposer(),
 434            lwe_decomposer: parameters.lwe_decomposer(),
 435            rlwe_rgsw_decomposer: parameters.rlwe_rgsw_decomposer(),
 436            g_k_dlog_map,
 437            embedding_factor,
 438            lwe_modop,
 439            rlwe_modop,
 440            rlwe_nttop,
 441            rlwe_qby4,
 442            rlwe_auto_maps,
 443            parameters: parameters,
 444        };
 445
 446        BoolEvaluator {
 447            pbs_info,
 448            scratch_memory,
 449            nand_test_vec,
 450            and_test_vec,
 451            or_test_vec,
 452            nor_test_vec,
 453            xnor_test_vec,
 454            xor_test_vec,
 455            _phantom: PhantomData,
 456        }
 457    }
 458
 459    pub(super) fn client_key(&self) -> ClientKey {
 460        let sk_lwe = LweSecret::random(
 461            self.pbs_info.parameters.lwe_n().0 >> 1,
 462            self.pbs_info.parameters.lwe_n().0,
 463        );
 464        let sk_rlwe = RlweSecret::random(
 465            self.pbs_info.parameters.rlwe_n().0 >> 1,
 466            self.pbs_info.parameters.rlwe_n().0,
 467        );
 468        ClientKey::new(sk_rlwe, sk_lwe)
 469    }
 470
 471    pub(super) fn server_key(
 472        &self,
 473        client_key: &ClientKey,
 474    ) -> SeededServerKey<M, BoolParameters<M::MatElement>, [u8; 32]> {
 475        DefaultSecureRng::with_local_mut(|rng| {
 476            let mut main_seed = [0u8; 32];
 477            rng.fill_bytes(&mut main_seed);
 478
 479            let mut main_prng = DefaultSecureRng::new_seeded(main_seed);
 480
 481            let rlwe_n = self.pbs_info.parameters.rlwe_n().0;
 482            let sk_rlwe = client_key.sk_rlwe();
 483            let sk_lwe = client_key.sk_lwe();
 484
 485            // generate auto keys
 486            let mut auto_keys = HashMap::new();
 487            let auto_gadget = self.pbs_info.auto_decomposer.gadget_vector();
 488            let g = self.pbs_info.parameters.g();
 489            let br_q = self.pbs_info.parameters.br_q();
 490            let auto_els = self.pbs_info.parameters.auto_element_dlogs();
 491            for i in auto_els.into_iter() {
 492                let g_pow = if i == 0 {
 493                    -(g as isize)
 494                } else {
 495                    (g.pow(i as u32) % br_q) as isize
 496                };
 497                let mut gk = M::zeros(self.pbs_info.auto_decomposer.decomposition_count(), rlwe_n);
 498                galois_key_gen(
 499                    &mut gk,
 500                    sk_rlwe.values(),
 501                    g_pow,
 502                    &auto_gadget,
 503                    &self.pbs_info.rlwe_modop,
 504                    &self.pbs_info.rlwe_nttop,
 505                    &mut main_prng,
 506                    rng,
 507                );
 508                auto_keys.insert(i, gk);
 509            }
 510
 511            // generate rgsw ciphertexts RGSW(si) where si is i^th LWE secret element
 512            let ring_size = self.pbs_info.parameters.rlwe_n().0;
 513            let rlwe_q = self.pbs_info.parameters.rlwe_q();
 514            let (rlrg_d_a, rlrg_d_b) = (
 515                self.pbs_info.rlwe_rgsw_decomposer.0.decomposition_count(),
 516                self.pbs_info.rlwe_rgsw_decomposer.1.decomposition_count(),
 517            );
 518            let rlrg_gadget_a = self.pbs_info.rlwe_rgsw_decomposer.0.gadget_vector();
 519            let rlrg_gadget_b = self.pbs_info.rlwe_rgsw_decomposer.1.gadget_vector();
 520            let rgsw_cts = sk_lwe
 521                .values()
 522                .iter()
 523                .map(|si| {
 524                    // X^{si}; assume |emebedding_factor * si| < N
 525                    let mut m = M::R::zeros(ring_size);
 526                    let si = (self.pbs_info.embedding_factor as i32) * si;
 527                    // dbg!(si);
 528                    if si < 0 {
 529                        // X^{-i} = X^{2N - i} = -X^{N-i}
 530                        m.as_mut()[ring_size - (si.abs() as usize)] = rlwe_q.neg_one();
 531                    } else {
 532                        // X^{i}
 533                        m.as_mut()[si.abs() as usize] = M::MatElement::one();
 534                    }
 535
 536                    let mut rgsw_si = M::zeros(rlrg_d_a * 2 + rlrg_d_b, ring_size);
 537                    secret_key_encrypt_rgsw(
 538                        &mut rgsw_si,
 539                        m.as_ref(),
 540                        &rlrg_gadget_a,
 541                        &rlrg_gadget_b,
 542                        sk_rlwe.values(),
 543                        &self.pbs_info.rlwe_modop,
 544                        &self.pbs_info.rlwe_nttop,
 545                        &mut main_prng,
 546                        rng,
 547                    );
 548
 549                    rgsw_si
 550                })
 551                .collect_vec();
 552
 553            // LWE KSK from RLWE secret s -> LWE secret z
 554            let d_lwe_gadget = self.pbs_info.lwe_decomposer.gadget_vector();
 555            let mut lwe_ksk =
 556                M::R::zeros(self.pbs_info.lwe_decomposer.decomposition_count() * ring_size);
 557            lwe_ksk_keygen(
 558                &sk_rlwe.values(),
 559                &sk_lwe.values(),
 560                &mut lwe_ksk,
 561                &d_lwe_gadget,
 562                &self.pbs_info.lwe_modop,
 563                &mut main_prng,
 564                rng,
 565            );
 566
 567            SeededServerKey::from_raw(
 568                auto_keys,
 569                rgsw_cts,
 570                lwe_ksk,
 571                self.pbs_info.parameters.clone(),
 572                main_seed,
 573            )
 574        })
 575    }
 576
 577    pub(super) fn multi_party_server_key_share(
 578        &self,
 579        cr_seed: [u8; 32],
 580        collective_pk: &M,
 581        client_key: &ClientKey,
 582    ) -> CommonReferenceSeededMultiPartyServerKeyShare<M, BoolParameters<M::MatElement>, [u8; 32]>
 583    {
 584        DefaultSecureRng::with_local_mut(|rng| {
 585            let mut main_prng = DefaultSecureRng::new_seeded(cr_seed);
 586
 587            let sk_rlwe = client_key.sk_rlwe();
 588            let sk_lwe = client_key.sk_lwe();
 589
 590            let g = self.pbs_info.parameters.g();
 591            let ring_size = self.pbs_info.parameters.rlwe_n().0;
 592            let rlwe_q = self.pbs_info.parameters.rlwe_q();
 593            let lwe_q = self.pbs_info.parameters.lwe_q();
 594
 595            let rlweq_modop = &self.pbs_info.rlwe_modop;
 596            let rlweq_nttop = &self.pbs_info.rlwe_nttop;
 597
 598            // sanity check
 599            assert!(sk_rlwe.values().len() == ring_size);
 600            assert!(sk_lwe.values().len() == self.pbs_info.parameters.lwe_n().0);
 601
 602            // auto keys
 603            let mut auto_keys = HashMap::new();
 604            let auto_gadget = self.pbs_info.auto_decomposer.gadget_vector();
 605            let auto_element_dlogs = self.pbs_info.parameters.auto_element_dlogs();
 606            let br_q = self.pbs_info.parameters.br_q();
 607            for i in auto_element_dlogs.into_iter() {
 608                let g_pow = if i == 0 {
 609                    -(g as isize)
 610                } else {
 611                    (g.pow(i as u32) % br_q) as isize
 612                };
 613
 614                let mut ksk_out = M::zeros(
 615                    self.pbs_info.auto_decomposer.decomposition_count(),
 616                    ring_size,
 617                );
 618                galois_key_gen(
 619                    &mut ksk_out,
 620                    sk_rlwe.values(),
 621                    g_pow,
 622                    &auto_gadget,
 623                    rlweq_modop,
 624                    rlweq_nttop,
 625                    &mut main_prng,
 626                    rng,
 627                );
 628                auto_keys.insert(i, ksk_out);
 629            }
 630
 631            // rgsw ciphertexts of lwe secret elements
 632            let rgsw_rgsw_decomposer = self
 633                .pbs_info
 634                .parameters
 635                .rgsw_rgsw_decomposer::<DefaultDecomposer<M::MatElement>>();
 636            let (rgrg_d_a, rgrg_d_b) = (
 637                rgsw_rgsw_decomposer.0.decomposition_count(),
 638                rgsw_rgsw_decomposer.1.decomposition_count(),
 639            );
 640            let (rgrg_gadget_a, rgrg_gadget_b) = (
 641                rgsw_rgsw_decomposer.0.gadget_vector(),
 642                rgsw_rgsw_decomposer.1.gadget_vector(),
 643            );
 644            let rgsw_cts = sk_lwe
 645                .values()
 646                .iter()
 647                .map(|si| {
 648                    let mut m = M::R::zeros(ring_size);
 649                    //TODO(Jay): It will be nice to have a function that returns polynomial
 650                    // (monomial infact!) corresponding to secret element embedded in ring X^{2N+1}.
 651                    // Save lots of mistakes where one forgest to emebed si in bigger ring.
 652                    let si = *si * (self.pbs_info.embedding_factor as i32);
 653                    if si < 0 {
 654                        // X^{-si} = X^{2N-si} = -X^{N-si}, assuming abs(si) < N
 655                        // (which it is given si is secret element)
 656                        m.as_mut()[ring_size - (si.abs() as usize)] = rlwe_q.neg_one();
 657                    } else {
 658                        m.as_mut()[si as usize] = M::MatElement::one();
 659                    }
 660
 661                    // public key RGSW encryption has no part that can be seeded, unlike secret key
 662                    // RGSW encryption where RLWE'_A(m) is seeded
 663                    let mut out_rgsw = M::zeros(rgrg_d_a * 2 + rgrg_d_b * 2, ring_size);
 664                    public_key_encrypt_rgsw(
 665                        &mut out_rgsw,
 666                        &m.as_ref(),
 667                        collective_pk,
 668                        &rgrg_gadget_a,
 669                        &rgrg_gadget_b,
 670                        rlweq_modop,
 671                        rlweq_nttop,
 672                        rng,
 673                    );
 674
 675                    out_rgsw
 676                })
 677                .collect_vec();
 678
 679            // LWE ksk
 680            let mut lwe_ksk =
 681                M::R::zeros(self.pbs_info.lwe_decomposer.decomposition_count() * ring_size);
 682            let lwe_modop = &self.pbs_info.lwe_modop;
 683            let d_lwe_gadget_vec = self.pbs_info.lwe_decomposer.gadget_vector();
 684            lwe_ksk_keygen(
 685                sk_rlwe.values(),
 686                sk_lwe.values(),
 687                &mut lwe_ksk,
 688                &d_lwe_gadget_vec,
 689                lwe_modop,
 690                &mut main_prng,
 691                rng,
 692            );
 693
 694            CommonReferenceSeededMultiPartyServerKeyShare::new(
 695                rgsw_cts,
 696                auto_keys,
 697                lwe_ksk,
 698                cr_seed,
 699                self.pbs_info.parameters.clone(),
 700            )
 701        })
 702    }
 703
 704    pub(super) fn multi_party_public_key_share(
 705        &self,
 706        cr_seed: [u8; 32],
 707        client_key: &ClientKey,
 708    ) -> CommonReferenceSeededCollectivePublicKeyShare<
 709        <M as Matrix>::R,
 710        [u8; 32],
 711        BoolParameters<<M as Matrix>::MatElement>,
 712    > {
 713        DefaultSecureRng::with_local_mut(|rng| {
 714            let mut share_out = M::R::zeros(self.pbs_info.parameters.rlwe_n().0);
 715            let modop = &self.pbs_info.rlwe_modop;
 716            let nttop = &self.pbs_info.rlwe_nttop;
 717            let mut main_prng = DefaultSecureRng::new_seeded(cr_seed);
 718            public_key_share(
 719                &mut share_out,
 720                client_key.sk_rlwe().values(),
 721                modop,
 722                nttop,
 723                &mut main_prng,
 724                rng,
 725            );
 726            CommonReferenceSeededCollectivePublicKeyShare::new(
 727                share_out,
 728                cr_seed,
 729                self.pbs_info.parameters.clone(),
 730            )
 731        })
 732    }
 733
 734    pub(super) fn multi_party_decryption_share(
 735        &self,
 736        lwe_ct: &M::R,
 737        client_key: &ClientKey,
 738    ) -> <M as Matrix>::MatElement {
 739        assert!(lwe_ct.as_ref().len() == self.pbs_info.parameters.rlwe_n().0 + 1);
 740        let modop = &self.pbs_info.rlwe_modop;
 741        let mut neg_s = M::R::try_convert_from(
 742            client_key.sk_rlwe().values(),
 743            &self.pbs_info.parameters.rlwe_q(),
 744        );
 745        modop.elwise_neg_mut(neg_s.as_mut());
 746
 747        let mut neg_sa = M::MatElement::zero();
 748        izip!(lwe_ct.as_ref().iter().skip(1), neg_s.as_ref().iter()).for_each(|(ai, nsi)| {
 749            neg_sa = modop.add(&neg_sa, &modop.mul(ai, nsi));
 750        });
 751
 752        let e = DefaultSecureRng::with_local_mut(|rng| {
 753            let mut e =
 754                RandomGaussianElementInModulus::random(rng, self.pbs_info.parameters.rlwe_q());
 755            e
 756        });
 757        let share = modop.add(&neg_sa, &e);
 758
 759        share
 760    }
 761
 762    pub(crate) fn multi_party_decrypt(&self, shares: &[M::MatElement], lwe_ct: &M::R) -> bool {
 763        let modop = &self.pbs_info.rlwe_modop;
 764        let mut sum_a = M::MatElement::zero();
 765        shares
 766            .iter()
 767            .for_each(|share_i| sum_a = modop.add(&sum_a, &share_i));
 768
 769        let encoded_m = modop.add(&lwe_ct.as_ref()[0], &sum_a);
 770        self.pbs_info.parameters.rlwe_q().decode(encoded_m)
 771    }
 772
 773    pub(crate) fn pk_encrypt(&self, pk: &M, m: bool) -> M::R {
 774        self.pk_encrypt_batched(pk, &vec![m]).remove(0)
 775    }
 776
 777    /// Encrypts a batch booleans as multiple LWE ciphertexts.
 778    ///
 779    /// For public key encryption we first encrypt `m` as a RLWE ciphertext and
 780    /// then sample extract LWE samples at required indices.
 781    ///
 782    /// - TODO(Jay:) Communication can be improved by not sample exctracting and
 783    ///   instead just truncate degree 0 values (part Bs)
 784    pub(crate) fn pk_encrypt_batched(&self, pk: &M, m: &[bool]) -> Vec<M::R> {
 785        DefaultSecureRng::with_local_mut(|rng| {
 786            let ring_size = self.pbs_info.parameters.rlwe_n().0;
 787            assert!(
 788                m.len() <= ring_size,
 789                "Cannot batch encrypt > ring_size{ring_size} elements at once"
 790            );
 791
 792            let modop = &self.pbs_info.rlwe_modop;
 793            let nttop = &self.pbs_info.rlwe_nttop;
 794
 795            // RLWE(0)
 796            // sample ephemeral key u
 797            let mut u = vec![0i32; ring_size];
 798            fill_random_ternary_secret_with_hamming_weight(u.as_mut(), ring_size >> 1, rng);
 799            let mut u = M::R::try_convert_from(&u, &self.pbs_info.parameters.rlwe_q());
 800            nttop.forward(u.as_mut());
 801
 802            let mut ua = M::R::zeros(ring_size);
 803            ua.as_mut().copy_from_slice(pk.get_row_slice(0));
 804            let mut ub = M::R::zeros(ring_size);
 805            ub.as_mut().copy_from_slice(pk.get_row_slice(1));
 806
 807            // a*u
 808            nttop.forward(ua.as_mut());
 809            modop.elwise_mul_mut(ua.as_mut(), u.as_ref());
 810            nttop.backward(ua.as_mut());
 811
 812            // b*u
 813            nttop.forward(ub.as_mut());
 814            modop.elwise_mul_mut(ub.as_mut(), u.as_ref());
 815            nttop.backward(ub.as_mut());
 816
 817            let mut rlwe = M::zeros(2, ring_size);
 818            // sample error
 819            rlwe.iter_rows_mut().for_each(|ri| {
 820                RandomFillGaussianInModulus::<[M::MatElement], CiphertextModulus<M::MatElement>>::random_fill(
 821                    rng,
 822                    &self.pbs_info.parameters.rlwe_q(),
 823                    ri.as_mut(),
 824                );
 825            });
 826
 827            // a*u + e0
 828            modop.elwise_add_mut(rlwe.get_row_mut(0), ua.as_ref());
 829            // b*u + e1
 830            modop.elwise_add_mut(rlwe.get_row_mut(1), ub.as_ref());
 831
 832            //FIXME(Jay): Figure out a way to get Q/8 form modulus
 833            let mut m_vec = M::R::zeros(ring_size);
 834            izip!(m_vec.as_mut().iter_mut(), m.iter()).for_each(|(m_el, m_bool)| {
 835                if *m_bool {
 836                    // Q/8
 837                    *m_el = self.pbs_info.rlwe_q().true_el()
 838                } else {
 839                    // -Q/8
 840                    *m_el = self.pbs_info.rlwe_q().false_el()
 841                }
 842            });
 843
 844            // b*u + e1 + m
 845            modop.elwise_add_mut(rlwe.get_row_mut(1), m_vec.as_ref());
 846            // rlwe.set(1, 0, modop.add(rlwe.get(1, 0), &m));
 847
 848            // sample extract index required indices
 849            let samples = m.len();
 850            (0..samples)
 851                .into_iter()
 852                .map(|i| {
 853                    let mut lwe_out = M::R::zeros(ring_size + 1);
 854                    sample_extract(&mut lwe_out, &rlwe, modop, i);
 855                    lwe_out
 856                })
 857                .collect_vec()
 858        })
 859    }
 860
 861    /// TODO(Jay): Fetch client key from thread local
 862    pub fn sk_encrypt(&self, m: bool, client_key: &ClientKey) -> M::R {
 863        //FIXME(Jay): Figure out a way to get Q/8 form modulus
 864        let m = if m {
 865            // Q/8
 866            self.pbs_info.rlwe_q().true_el()
 867        } else {
 868            // -Q/8
 869            self.pbs_info.rlwe_q().false_el()
 870        };
 871
 872        DefaultSecureRng::with_local_mut(|rng| {
 873            let mut lwe_out = M::R::zeros(self.pbs_info.parameters.rlwe_n().0 + 1);
 874            encrypt_lwe(
 875                &mut lwe_out,
 876                &m,
 877                client_key.sk_rlwe().values(),
 878                &self.pbs_info.rlwe_modop,
 879                rng,
 880            );
 881            lwe_out
 882        })
 883    }
 884
 885    pub fn sk_decrypt(&self, lwe_ct: &M::R, client_key: &ClientKey) -> bool {
 886        let m = decrypt_lwe(
 887            lwe_ct,
 888            client_key.sk_rlwe().values(),
 889            &self.pbs_info.rlwe_modop,
 890        );
 891        self.pbs_info.rlwe_q().decode(m)
 892    }
 893
 894    pub(super) fn aggregate_multi_party_server_key_shares<S>(
 895        &self,
 896        shares: &[CommonReferenceSeededMultiPartyServerKeyShare<
 897            M,
 898            BoolParameters<M::MatElement>,
 899            S,
 900        >],
 901    ) -> SeededMultiPartyServerKey<M, S, BoolParameters<M::MatElement>>
 902    where
 903        S: PartialEq + Clone,
 904        M: Clone,
 905    {
 906        assert!(shares.len() > 0);
 907        let parameters = shares[0].parameters().clone();
 908        let cr_seed = shares[0].cr_seed();
 909
 910        let rlwe_n = parameters.rlwe_n().0;
 911        let g = parameters.g() as isize;
 912        let rlwe_q = parameters.rlwe_q();
 913        let lwe_q = parameters.lwe_q();
 914
 915        // sanity checks
 916        shares.iter().skip(1).for_each(|s| {
 917            assert!(s.parameters() == &parameters);
 918            assert!(s.cr_seed() == cr_seed);
 919        });
 920
 921        let rlweq_modop = &self.pbs_info.rlwe_modop;
 922        let rlweq_nttop = &self.pbs_info.rlwe_nttop;
 923
 924        // auto keys
 925        let mut auto_keys = HashMap::new();
 926        let auto_elements_dlog = parameters.auto_element_dlogs();
 927        for i in auto_elements_dlog.into_iter() {
 928            let mut key = M::zeros(parameters.auto_decomposition_count().0, rlwe_n);
 929
 930            shares.iter().for_each(|s| {
 931                let auto_key_share_i = s.auto_keys().get(&i).expect("Auto key {i} missing");
 932                assert!(
 933                    auto_key_share_i.dimension()
 934                        == (parameters.auto_decomposition_count().0, rlwe_n)
 935                );
 936                izip!(key.iter_rows_mut(), auto_key_share_i.iter_rows()).for_each(
 937                    |(partb_out, partb_share)| {
 938                        rlweq_modop.elwise_add_mut(partb_out.as_mut(), partb_share.as_ref());
 939                    },
 940                );
 941            });
 942
 943            auto_keys.insert(i, key);
 944        }
 945
 946        // rgsw ciphertext (most expensive part!)
 947        let lwe_n = parameters.lwe_n().0;
 948        let rgsw_by_rgsw_decomposer =
 949            parameters.rgsw_rgsw_decomposer::<DefaultDecomposer<M::MatElement>>();
 950        let mut scratch_matrix = M::zeros(
 951            std::cmp::max(
 952                rgsw_by_rgsw_decomposer.a().decomposition_count(),
 953                rgsw_by_rgsw_decomposer.b().decomposition_count(),
 954            ) + (rgsw_by_rgsw_decomposer.a().decomposition_count() * 2
 955                + rgsw_by_rgsw_decomposer.b().decomposition_count() * 2),
 956            rlwe_n,
 957        );
 958
 959        let mut tmp_rgsw =
 960            RgswCiphertext::<M, _>::empty(rlwe_n, &rgsw_by_rgsw_decomposer, rlwe_q.clone()).data;
 961        let rgsw_cts = (0..lwe_n).into_iter().map(|index| {
 962            // copy over rgsw ciphertext for index^th secret element from first share and
 963            // treat it as accumulating rgsw ciphertext
 964            let mut rgsw_i = shares[0].rgsw_cts()[index].clone();
 965
 966            shares.iter().skip(1).for_each(|si| {
 967                // copy over si's RGSW[index] ciphertext and send to evaluation domain
 968                izip!(tmp_rgsw.iter_rows_mut(), si.rgsw_cts()[index].iter_rows()).for_each(
 969                    |(to_ri, from_ri)| {
 970                        to_ri.as_mut().copy_from_slice(from_ri.as_ref());
 971                        rlweq_nttop.forward(to_ri.as_mut())
 972                    },
 973                );
 974
 975                rgsw_by_rgsw_inplace(
 976                    &mut rgsw_i,
 977                    &tmp_rgsw,
 978                    &rgsw_by_rgsw_decomposer,
 979                    &mut scratch_matrix,
 980                    rlweq_nttop,
 981                    rlweq_modop,
 982                );
 983            });
 984
 985            rgsw_i
 986        });
 987        // d_a and d_b may differ for RGSWxRGSW multiplication and RLWExRGSW
 988        // multiplication. After this point RGSW ciphertexts will only be used for
 989        // RLWExRGSW multiplication (in blind rotation). Thus we drop any additional
 990        // RLWE ciphertexts in RGSW ciphertexts after RGSw x RGSW multiplication
 991        let (rgswrgsw_d_a, rgswrgsw_d_b) = self.pbs_info.parameters.rgsw_rgsw_decomposition_count();
 992        let (rlrg_d_a, rlrg_d_b) = self.pbs_info.parameters.rlwe_rgsw_decomposition_count();
 993        let rgsw_ct_rows_in = rgswrgsw_d_a.0 * 2 + rgswrgsw_d_b.0 * 2;
 994        let rgsw_ct_rows_out = rlrg_d_a.0 * 2 + rlrg_d_b.0 * 2;
 995        assert!(rgswrgsw_d_a.0 >= rlrg_d_a.0, "RGSWxRGSW part A decomposition count {} must be >= RLWExRGSW part A decomposition count {}", rgswrgsw_d_a.0 , rlrg_d_a.0);
 996        assert!(rgswrgsw_d_b.0 >= rlrg_d_b.0, "RGSWxRGSW part B decomposition count {} must be >= RLWExRGSW part B decomposition count {}", rgswrgsw_d_b.0 , rlrg_d_b.0);
 997        let rgsw_cts = rgsw_cts
 998            .map(|ct_i_in| {
 999                assert!(ct_i_in.dimension() == (rgsw_ct_rows_in, rlwe_n));
1000                let mut reduced_ct_i_out = M::zeros(rgsw_ct_rows_out, rlwe_n);
1001
1002                // RLWE'(-sm) part A
1003                izip!(
1004                    reduced_ct_i_out.iter_rows_mut().take(rlrg_d_a.0),
1005                    ct_i_in
1006                        .iter_rows()
1007                        .skip(rgswrgsw_d_a.0 - rlrg_d_a.0)
1008                        .take(rlrg_d_a.0)
1009                )
1010                .for_each(|(to_ri, from_ri)| {
1011                    to_ri.as_mut().copy_from_slice(from_ri.as_ref());
1012                });
1013
1014                // RLWE'(-sm) part B
1015                izip!(
1016                    reduced_ct_i_out
1017                        .iter_rows_mut()
1018                        .skip(rlrg_d_a.0)
1019                        .take(rlrg_d_a.0),
1020                    ct_i_in
1021                        .iter_rows()
1022                        .skip(rgswrgsw_d_a.0 + (rgswrgsw_d_a.0 - rlrg_d_a.0))
1023                        .take(rlrg_d_a.0)
1024                )
1025                .for_each(|(to_ri, from_ri)| {
1026                    to_ri.as_mut().copy_from_slice(from_ri.as_ref());
1027                });
1028
1029                // RLWE'(m) Part A
1030                izip!(
1031                    reduced_ct_i_out
1032                        .iter_rows_mut()
1033                        .skip(rlrg_d_a.0 * 2)
1034                        .take(rlrg_d_b.0),
1035                    ct_i_in
1036                        .iter_rows()
1037                        .skip(rgswrgsw_d_a.0 * 2 + (rgswrgsw_d_b.0 - rlrg_d_b.0))
1038                        .take(rlrg_d_b.0)
1039                )
1040                .for_each(|(to_ri, from_ri)| {
1041                    to_ri.as_mut().copy_from_slice(from_ri.as_ref());
1042                });
1043
1044                // RLWE'(m) Part B
1045                izip!(
1046                    reduced_ct_i_out
1047                        .iter_rows_mut()
1048                        .skip(rlrg_d_a.0 * 2 + rlrg_d_b.0)
1049                        .take(rlrg_d_b.0),
1050                    ct_i_in
1051                        .iter_rows()
1052                        .skip(rgswrgsw_d_a.0 * 2 + rgswrgsw_d_b.0 + (rgswrgsw_d_b.0 - rlrg_d_b.0))
1053                        .take(rlrg_d_b.0)
1054                )
1055                .for_each(|(to_ri, from_ri)| {
1056                    to_ri.as_mut().copy_from_slice(from_ri.as_ref());
1057                });
1058
1059                reduced_ct_i_out
1060            })
1061            .collect_vec();
1062
1063        // LWE ksks
1064        let mut lwe_ksk = M::R::zeros(rlwe_n * parameters.lwe_decomposition_count().0);
1065        let lweq_modop = &self.pbs_info.lwe_modop;
1066        shares.iter().for_each(|si| {
1067            assert!(si.lwe_ksk().as_ref().len() == rlwe_n * parameters.lwe_decomposition_count().0);
1068            lweq_modop.elwise_add_mut(lwe_ksk.as_mut(), si.lwe_ksk().as_ref())
1069        });
1070
1071        SeededMultiPartyServerKey::new(rgsw_cts, auto_keys, lwe_ksk, cr_seed.clone(), parameters)
1072    }
1073}
1074
1075impl<M, NttOp, RlweModOp, LweModOp> BoolEvaluator<M, NttOp, RlweModOp, LweModOp>
1076where
1077    M: MatrixMut + MatrixEntity,
1078    M::R: RowMut + RowEntity,
1079    M::MatElement: PrimInt + FromPrimitive + One + Copy + Zero + Display + WrappingSub + NumInfo,
1080    RlweModOp: VectorOps<Element = M::MatElement>
1081        + ArithmeticOps<Element = M::MatElement>
1082        + GetModulus<Element = M::MatElement, M = CiphertextModulus<M::MatElement>>,
1083    LweModOp: VectorOps<Element = M::MatElement>
1084        + ArithmeticOps<Element = M::MatElement>
1085        + GetModulus<Element = M::MatElement, M = CiphertextModulus<M::MatElement>>,
1086    NttOp: Ntt<Element = M::MatElement>,
1087{
1088    /// Returns c0 + c1 + Q/4
1089    fn _add_and_shift_lwe_cts(&self, c0: &mut M::R, c1: &M::R) {
1090        let modop = &self.pbs_info.rlwe_modop;
1091        modop.elwise_add_mut(c0.as_mut(), c1.as_ref());
1092        // +Q/4
1093        c0.as_mut()[0] = modop.add(&c0.as_ref()[0], &self.pbs_info.rlwe_qby4);
1094    }
1095
1096    /// Returns 2(c0 - c1) + Q/4
1097    fn _subtract_double_lwe_cts(&self, c0: &mut M::R, c1: &M::R) {
1098        let modop = &self.pbs_info.rlwe_modop;
1099        // c0 - c1
1100        modop.elwise_sub_mut(c0.as_mut(), c1.as_ref());
1101
1102        // double
1103        c0.as_mut().iter_mut().for_each(|v| *v = modop.add(v, v));
1104    }
1105}
1106
1107impl<M, NttOp, RlweModOp, LweModOp> BooleanGates for BoolEvaluator<M, NttOp, RlweModOp, LweModOp>
1108where
1109    M: MatrixMut + MatrixEntity,
1110    M::R: RowMut + RowEntity + Clone,
1111    M::MatElement: PrimInt + FromPrimitive + One + Copy + Zero + Display + WrappingSub + NumInfo,
1112    RlweModOp: VectorOps<Element = M::MatElement>
1113        + ArithmeticOps<Element = M::MatElement>
1114        + GetModulus<Element = M::MatElement, M = CiphertextModulus<M::MatElement>>,
1115    LweModOp: VectorOps<Element = M::MatElement>
1116        + ArithmeticOps<Element = M::MatElement>
1117        + GetModulus<Element = M::MatElement, M = CiphertextModulus<M::MatElement>>,
1118    NttOp: Ntt<Element = M::MatElement>,
1119{
1120    type Ciphertext = M::R;
1121    type Key = ServerKeyEvaluationDomain<M, DefaultSecureRng, NttOp>;
1122
1123    fn nand_inplace(
1124        &mut self,
1125        c0: &mut M::R,
1126        c1: &M::R,
1127        server_key: &ServerKeyEvaluationDomain<M, DefaultSecureRng, NttOp>,
1128    ) {
1129        self._add_and_shift_lwe_cts(c0, c1);
1130
1131        // PBS
1132        pbs(
1133            &self.pbs_info,
1134            &self.nand_test_vec,
1135            c0,
1136            server_key,
1137            &mut self.scratch_memory.lwe_vector,
1138            &mut self.scratch_memory.decomposition_matrix,
1139        );
1140    }
1141
1142    fn and_inplace(
1143        &mut self,
1144        c0: &mut M::R,
1145        c1: &M::R,
1146        server_key: &ServerKeyEvaluationDomain<M, DefaultSecureRng, NttOp>,
1147    ) {
1148        self._add_and_shift_lwe_cts(c0, c1);
1149
1150        // PBS
1151        pbs(
1152            &self.pbs_info,
1153            &self.and_test_vec,
1154            c0,
1155            server_key,
1156            &mut self.scratch_memory.lwe_vector,
1157            &mut self.scratch_memory.decomposition_matrix,
1158        );
1159    }
1160
1161    fn or_inplace(
1162        &mut self,
1163        c0: &mut M::R,
1164        c1: &M::R,
1165        server_key: &ServerKeyEvaluationDomain<M, DefaultSecureRng, NttOp>,
1166    ) {
1167        self._add_and_shift_lwe_cts(c0, c1);
1168
1169        // PBS
1170        pbs(
1171            &self.pbs_info,
1172            &self.or_test_vec,
1173            c0,
1174            server_key,
1175            &mut self.scratch_memory.lwe_vector,
1176            &mut self.scratch_memory.decomposition_matrix,
1177        );
1178    }
1179
1180    fn nor_inplace(
1181        &mut self,
1182        c0: &mut M::R,
1183        c1: &M::R,
1184        server_key: &ServerKeyEvaluationDomain<M, DefaultSecureRng, NttOp>,
1185    ) {
1186        self._add_and_shift_lwe_cts(c0, c1);
1187
1188        // PBS
1189        pbs(
1190            &self.pbs_info,
1191            &self.nor_test_vec,
1192            c0,
1193            server_key,
1194            &mut self.scratch_memory.lwe_vector,
1195            &mut self.scratch_memory.decomposition_matrix,
1196        )
1197    }
1198
1199    fn xor_inplace(
1200        &mut self,
1201        c0: &mut M::R,
1202        c1: &M::R,
1203        server_key: &ServerKeyEvaluationDomain<M, DefaultSecureRng, NttOp>,
1204    ) {
1205        self._subtract_double_lwe_cts(c0, c1);
1206
1207        // PBS
1208        pbs(
1209            &self.pbs_info,
1210            &self.xor_test_vec,
1211            c0,
1212            server_key,
1213            &mut self.scratch_memory.lwe_vector,
1214            &mut self.scratch_memory.decomposition_matrix,
1215        );
1216    }
1217
1218    fn xnor_inplace(
1219        &mut self,
1220        c0: &mut M::R,
1221        c1: &M::R,
1222        server_key: &ServerKeyEvaluationDomain<M, DefaultSecureRng, NttOp>,
1223    ) {
1224        self._subtract_double_lwe_cts(c0, c1);
1225
1226        // PBS
1227        pbs(
1228            &self.pbs_info,
1229            &self.xnor_test_vec,
1230            c0,
1231            server_key,
1232            &mut self.scratch_memory.lwe_vector,
1233            &mut self.scratch_memory.decomposition_matrix,
1234        );
1235    }
1236
1237    fn not_inplace(&mut self, c0: &mut M::R) {
1238        let modop = &self.pbs_info.rlwe_modop;
1239        c0.as_mut().iter_mut().for_each(|v| *v = modop.neg(v));
1240    }
1241
1242    fn and(
1243        &mut self,
1244        c0: &Self::Ciphertext,
1245        c1: &Self::Ciphertext,
1246        key: &Self::Key,
1247    ) -> Self::Ciphertext {
1248        let mut out = c0.clone();
1249        self.and_inplace(&mut out, c1, key);
1250        out
1251    }
1252
1253    fn nand(
1254        &mut self,
1255        c0: &Self::Ciphertext,
1256        c1: &Self::Ciphertext,
1257        key: &Self::Key,
1258    ) -> Self::Ciphertext {
1259        let mut out = c0.clone();
1260        self.nand_inplace(&mut out, c1, key);
1261        out
1262    }
1263
1264    fn or(
1265        &mut self,
1266        c0: &Self::Ciphertext,
1267        c1: &Self::Ciphertext,
1268        key: &Self::Key,
1269    ) -> Self::Ciphertext {
1270        let mut out = c0.clone();
1271        self.or_inplace(&mut out, c1, key);
1272        out
1273    }
1274
1275    fn nor(
1276        &mut self,
1277        c0: &Self::Ciphertext,
1278        c1: &Self::Ciphertext,
1279        key: &Self::Key,
1280    ) -> Self::Ciphertext {
1281        let mut out = c0.clone();
1282        self.nor_inplace(&mut out, c1, key);
1283        out
1284    }
1285
1286    fn xnor(
1287        &mut self,
1288        c0: &Self::Ciphertext,
1289        c1: &Self::Ciphertext,
1290        key: &Self::Key,
1291    ) -> Self::Ciphertext {
1292        let mut out = c0.clone();
1293        self.xnor_inplace(&mut out, c1, key);
1294        out
1295    }
1296
1297    fn xor(
1298        &mut self,
1299        c0: &Self::Ciphertext,
1300        c1: &Self::Ciphertext,
1301        key: &Self::Key,
1302    ) -> Self::Ciphertext {
1303        let mut out = c0.clone();
1304        self.xor_inplace(&mut out, c1, key);
1305        out
1306    }
1307
1308    fn not(&mut self, c: &Self::Ciphertext) -> Self::Ciphertext {
1309        let mut out = c.clone();
1310        self.not_inplace(&mut out);
1311        out
1312    }
1313}
1314
1315#[cfg(test)]
1316mod tests {
1317    use bool::parameters::{MP_BOOL_PARAMS, SP_BOOL_PARAMS};
1318    use rand::{thread_rng, Rng};
1319    use rand_distr::Uniform;
1320
1321    use crate::{
1322        backend::{GetModulus, ModInit, ModularOpsU64, WordSizeModulus},
1323        bool::{
1324            self, CommonReferenceSeededMultiPartyServerKeyShare, PublicKey,
1325            SeededMultiPartyServerKey,
1326        },
1327        ntt::NttBackendU64,
1328        random::{RandomElementInModulus, DEFAULT_RNG},
1329        rgsw::{
1330            self, measure_noise, public_key_encrypt_rlwe, secret_key_encrypt_rlwe,
1331            tests::{_measure_noise_rgsw, _sk_encrypt_rlwe},
1332            RgswCiphertext, RgswCiphertextEvaluationDomain, SeededRgswCiphertext,
1333            SeededRlweCiphertext,
1334        },
1335        utils::{negacyclic_mul, Stats},
1336    };
1337
1338    use super::*;
1339
1340    #[test]
1341    fn bool_encrypt_decrypt_works() {
1342        let bool_evaluator = BoolEvaluator::<
1343            Vec<Vec<u64>>,
1344            NttBackendU64,
1345            ModularOpsU64<CiphertextModulus<u64>>,
1346            ModularOpsU64<CiphertextModulus<u64>>,
1347        >::new(SP_BOOL_PARAMS);
1348        let client_key = bool_evaluator.client_key();
1349
1350        let mut m = true;
1351        for _ in 0..1000 {
1352            let lwe_ct = bool_evaluator.sk_encrypt(m, &client_key);
1353            let m_back = bool_evaluator.sk_decrypt(&lwe_ct, &client_key);
1354            assert_eq!(m, m_back);
1355            m = !m;
1356        }
1357    }
1358
1359    #[test]
1360    fn bool_nand() {
1361        let mut bool_evaluator = BoolEvaluator::<
1362            Vec<Vec<u64>>,
1363            NttBackendU64,
1364            ModularOpsU64<CiphertextModulus<u64>>,
1365            ModularOpsU64<CiphertextModulus<u64>>,
1366        >::new(SP_BOOL_PARAMS);
1367
1368        // println!("{:?}", bool_evaluator.nand_test_vec);
1369        let client_key = bool_evaluator.client_key();
1370        let seeded_server_key = bool_evaluator.server_key(&client_key);
1371        let server_key_eval_domain =
1372            ServerKeyEvaluationDomain::<_, DefaultSecureRng, NttBackendU64>::from(
1373                &seeded_server_key,
1374            );
1375
1376        let mut m0 = false;
1377        let mut m1 = true;
1378
1379        let mut ct0 = bool_evaluator.sk_encrypt(m0, &client_key);
1380        let mut ct1 = bool_evaluator.sk_encrypt(m1, &client_key);
1381
1382        for _ in 0..500 {
1383            let ct_back = bool_evaluator.nand(&ct0, &ct1, &server_key_eval_domain);
1384
1385            let m_out = !(m0 && m1);
1386
1387            // Trace and measure PBS noise
1388            {
1389                let noise0 = {
1390                    let ideal = if m0 {
1391                        bool_evaluator.pbs_info.parameters.rlwe_q().true_el()
1392                    } else {
1393                        bool_evaluator.pbs_info.parameters.rlwe_q().false_el()
1394                    };
1395                    let n = measure_noise_lwe(
1396                        &ct0,
1397                        client_key.sk_rlwe().values(),
1398                        &bool_evaluator.pbs_info.rlwe_modop,
1399                        &ideal,
1400                    );
1401                    let v = decrypt_lwe(
1402                        &ct0,
1403                        client_key.sk_rlwe().values(),
1404                        &bool_evaluator.pbs_info.rlwe_modop,
1405                    );
1406                    (n, v)
1407                };
1408                let noise1 = {
1409                    let ideal = if m1 {
1410                        bool_evaluator.pbs_info.parameters.rlwe_q().true_el()
1411                    } else {
1412                        bool_evaluator.pbs_info.parameters.rlwe_q().false_el()
1413                    };
1414                    let n = measure_noise_lwe(
1415                        &ct1,
1416                        client_key.sk_rlwe().values(),
1417                        &bool_evaluator.pbs_info.rlwe_modop,
1418                        &ideal,
1419                    );
1420                    let v = decrypt_lwe(
1421                        &ct1,
1422                        client_key.sk_rlwe().values(),
1423                        &bool_evaluator.pbs_info.rlwe_modop,
1424                    );
1425                    (n, v)
1426                };
1427
1428                // Calculate noise in ciphertext post PBS
1429                let noise_out = {
1430                    let ideal = if m_out {
1431                        bool_evaluator.pbs_info.parameters.rlwe_q().true_el()
1432                    } else {
1433                        bool_evaluator.pbs_info.parameters.rlwe_q().false_el()
1434                    };
1435                    let n = measure_noise_lwe(
1436                        &ct_back,
1437                        client_key.sk_rlwe().values(),
1438                        &bool_evaluator.pbs_info.rlwe_modop,
1439                        &ideal,
1440                    );
1441                    let v = decrypt_lwe(
1442                        &ct_back,
1443                        client_key.sk_rlwe().values(),
1444                        &bool_evaluator.pbs_info.rlwe_modop,
1445                    );
1446                    (n, v)
1447                };
1448                dbg!(m0, m1, m_out);
1449                println!(
1450                    "ct0 (noise, message): {:?}  \n ct1 (noise, message): {:?} \n PBS (noise, message): {:?}", noise0, noise1, noise_out
1451                );
1452            }
1453            let m_back = bool_evaluator.sk_decrypt(&ct_back, &client_key);
1454            assert!(m_out == m_back, "Expected {m_out}, got {m_back}");
1455            println!("----------");
1456
1457            m1 = m0;
1458            m0 = m_out;
1459
1460            ct1 = ct0;
1461            ct0 = ct_back;
1462        }
1463    }
1464
1465    #[test]
1466    fn bool_xor() {
1467        let mut bool_evaluator = BoolEvaluator::<
1468            Vec<Vec<u64>>,
1469            NttBackendU64,
1470            ModularOpsU64<CiphertextModulus<u64>>,
1471            ModularOpsU64<CiphertextModulus<u64>>,
1472        >::new(SP_BOOL_PARAMS);
1473
1474        // println!("{:?}", bool_evaluator.nand_test_vec);
1475        let client_key = bool_evaluator.client_key();
1476        let seeded_server_key = bool_evaluator.server_key(&client_key);
1477        let server_key_eval_domain =
1478            ServerKeyEvaluationDomain::<_, DefaultSecureRng, NttBackendU64>::from(
1479                &seeded_server_key,
1480            );
1481
1482        let mut m0 = false;
1483        let mut m1 = true;
1484
1485        let mut ct0 = bool_evaluator.sk_encrypt(m0, &client_key);
1486        let mut ct1 = bool_evaluator.sk_encrypt(m1, &client_key);
1487
1488        for _ in 0..1000 {
1489            let ct_back = bool_evaluator.xor(&ct0, &ct1, &server_key_eval_domain);
1490            let m_out = (m0 ^ m1);
1491
1492            let m_back = bool_evaluator.sk_decrypt(&ct_back, &client_key);
1493            assert!(m_out == m_back, "Expected {m_out}, got {m_back}");
1494
1495            m1 = m0;
1496            m0 = m_out;
1497
1498            ct1 = ct0;
1499            ct0 = ct_back;
1500        }
1501    }
1502
1503    #[test]
1504    fn multi_party_encryption_decryption() {
1505        let bool_evaluator = BoolEvaluator::<
1506            Vec<Vec<u64>>,
1507            NttBackendU64,
1508            ModularOpsU64<CiphertextModulus<u64>>,
1509            ModularOpsU64<CiphertextModulus<u64>>,
1510        >::new(MP_BOOL_PARAMS);
1511
1512        let no_of_parties = 500;
1513        let parties = (0..no_of_parties)
1514            .map(|_| bool_evaluator.client_key())
1515            .collect_vec();
1516
1517        let mut ideal_rlwe_sk = vec![0i32; bool_evaluator.pbs_info.rlwe_n()];
1518        parties.iter().for_each(|k| {
1519            izip!(ideal_rlwe_sk.iter_mut(), k.sk_rlwe().values()).for_each(|(ideal_i, s_i)| {
1520                *ideal_i = *ideal_i + s_i;
1521            });
1522        });
1523
1524        println!("{:?}", &ideal_rlwe_sk);
1525
1526        let mut m = true;
1527        for i in 0..100 {
1528            let pk_cr_seed = [0u8; 32];
1529
1530            let public_key_share = parties
1531                .iter()
1532                .map(|k| bool_evaluator.multi_party_public_key_share(pk_cr_seed, k))
1533                .collect_vec();
1534
1535            let collective_pk = PublicKey::<
1536                Vec<Vec<u64>>,
1537                DefaultSecureRng,
1538                ModularOpsU64<CiphertextModulus<u64>>,
1539            >::from(public_key_share.as_slice());
1540            let lwe_ct = bool_evaluator.pk_encrypt(collective_pk.key(), m);
1541
1542            let decryption_shares = parties
1543                .iter()
1544                .map(|k| bool_evaluator.multi_party_decryption_share(&lwe_ct, k))
1545                .collect_vec();
1546
1547            let m_back = bool_evaluator.multi_party_decrypt(&decryption_shares, &lwe_ct);
1548
1549            {
1550                let ideal_m = if m {
1551                    bool_evaluator.pbs_info.parameters.rlwe_q().true_el()
1552                } else {
1553                    bool_evaluator.pbs_info.parameters.rlwe_q().false_el()
1554                };
1555                let noise = measure_noise_lwe(
1556                    &lwe_ct,
1557                    &ideal_rlwe_sk,
1558                    &bool_evaluator.pbs_info.rlwe_modop,
1559                    &ideal_m,
1560                );
1561                println!("Noise: {noise}");
1562            }
1563
1564            assert_eq!(m_back, m);
1565            m = !m;
1566        }
1567    }
1568
1569    fn _collecitve_public_key_gen(rlwe_q: u64, parties_rlwe_sk: &[RlweSecret]) -> Vec<Vec<u64>> {
1570        let ring_size = parties_rlwe_sk[0].values.len();
1571        assert!(ring_size.is_power_of_two());
1572        let mut rng = DefaultSecureRng::new();
1573        let nttop = NttBackendU64::new(&rlwe_q, ring_size);
1574        let modop = ModularOpsU64::new(rlwe_q);
1575
1576        // Generate Pk shares
1577        let pk_seed = [0u8; 32];
1578        let pk_shares = parties_rlwe_sk.iter().map(|sk| {
1579            let mut p_rng = DefaultSecureRng::new_seeded(pk_seed);
1580            let mut share_out = vec![0u64; ring_size];
1581            public_key_share(
1582                &mut share_out,
1583                sk.values(),
1584                &modop,
1585                &nttop,
1586                &mut p_rng,
1587                &mut rng,
1588            );
1589            share_out
1590        });
1591
1592        let mut pk_part_b = vec![0u64; ring_size];
1593        pk_shares.for_each(|share| modop.elwise_add_mut(&mut pk_part_b, &share));
1594        let mut pk_part_a = vec![0u64; ring_size];
1595        let mut p_rng = DefaultSecureRng::new_seeded(pk_seed);
1596        RandomFillUniformInModulus::random_fill(&mut p_rng, &rlwe_q, pk_part_a.as_mut_slice());
1597
1598        vec![pk_part_a, pk_part_b]
1599    }
1600
1601    fn _multi_party_all_keygen(
1602        bool_evaluator: &BoolEvaluator<
1603            Vec<Vec<u64>>,
1604            NttBackendU64,
1605            ModularOpsU64<CiphertextModulus<u64>>,
1606            ModularOpsU64<CiphertextModulus<u64>>,
1607        >,
1608        no_of_parties: usize,
1609    ) -> (
1610        Vec<ClientKey>,
1611        PublicKey<Vec<Vec<u64>>, DefaultSecureRng, ModularOpsU64<CiphertextModulus<u64>>>,
1612        Vec<
1613            CommonReferenceSeededMultiPartyServerKeyShare<
1614                Vec<Vec<u64>>,
1615                BoolParameters<u64>,
1616                [u8; 32],
1617            >,
1618        >,
1619        SeededMultiPartyServerKey<Vec<Vec<u64>>, [u8; 32], BoolParameters<u64>>,
1620        ServerKeyEvaluationDomain<Vec<Vec<u64>>, DefaultSecureRng, NttBackendU64>,
1621        ClientKey,
1622    ) {
1623        let parties = (0..no_of_parties)
1624            .map(|_| bool_evaluator.client_key())
1625            .collect_vec();
1626
1627        let mut rng = DefaultSecureRng::new();
1628
1629        // Collective public key
1630        let mut pk_cr_seed = [0u8; 32];
1631        rng.fill_bytes(&mut pk_cr_seed);
1632        let public_key_share = parties
1633            .iter()
1634            .map(|k| bool_evaluator.multi_party_public_key_share(pk_cr_seed, k))
1635            .collect_vec();
1636        let collective_pk =
1637            PublicKey::<Vec<Vec<u64>>, DefaultSecureRng, _>::from(public_key_share.as_slice());
1638
1639        // Server key
1640        let mut pbs_cr_seed = [0u8; 32];
1641        rng.fill_bytes(&mut pbs_cr_seed);
1642        let server_key_shares = parties
1643            .iter()
1644            .map(|k| {
1645                bool_evaluator.multi_party_server_key_share(pbs_cr_seed, &collective_pk.key(), k)
1646            })
1647            .collect_vec();
1648        let seeded_server_key =
1649            bool_evaluator.aggregate_multi_party_server_key_shares(&server_key_shares);
1650        let server_key_eval = ServerKeyEvaluationDomain::<_, DefaultSecureRng, NttBackendU64>::from(
1651            &seeded_server_key,
1652        );
1653
1654        // construct ideal rlwe sk for meauring noise
1655        let ideal_client_key = {
1656            let mut ideal_rlwe_sk = vec![0i32; bool_evaluator.pbs_info.rlwe_n()];
1657            parties.iter().for_each(|k| {
1658                izip!(ideal_rlwe_sk.iter_mut(), k.sk_rlwe().values()).for_each(|(ideal_i, s_i)| {
1659                    *ideal_i = *ideal_i + s_i;
1660                });
1661            });
1662            let mut ideal_lwe_sk = vec![0i32; bool_evaluator.pbs_info.lwe_n()];
1663            parties.iter().for_each(|k| {
1664                izip!(ideal_lwe_sk.iter_mut(), k.sk_lwe().values()).for_each(|(ideal_i, s_i)| {
1665                    *ideal_i = *ideal_i + s_i;
1666                });
1667            });
1668
1669            ClientKey::new(
1670                RlweSecret {
1671                    values: ideal_rlwe_sk,
1672                },
1673                LweSecret {
1674                    values: ideal_lwe_sk,
1675                },
1676            )
1677        };
1678
1679        (
1680            parties,
1681            collective_pk,
1682            server_key_shares,
1683            seeded_server_key,
1684            server_key_eval,
1685            ideal_client_key,
1686        )
1687    }
1688
1689    #[test]
1690    fn multi_party_nand() {
1691        let mut bool_evaluator = BoolEvaluator::<
1692            Vec<Vec<u64>>,
1693            NttBackendU64,
1694            ModularOpsU64<CiphertextModulus<u64>>,
1695            ModularOpsU64<CiphertextModulus<u64>>,
1696        >::new(MP_BOOL_PARAMS);
1697
1698        let (parties, collective_pk, _, _, server_key_eval, ideal_client_key) =
1699            _multi_party_all_keygen(&bool_evaluator, 2);
1700
1701        let mut m0 = true;
1702        let mut m1 = false;
1703
1704        let mut lwe0 = bool_evaluator.pk_encrypt(collective_pk.key(), m0);
1705        let mut lwe1 = bool_evaluator.pk_encrypt(collective_pk.key(), m1);
1706
1707        for _ in 0..2000 {
1708            let lwe_out = bool_evaluator.nand(&lwe0, &lwe1, &server_key_eval);
1709
1710            let m_expected = !(m0 & m1);
1711
1712            // measure noise
1713            {
1714                let noise0 = {
1715                    let ideal = if m0 {
1716                        bool_evaluator.pbs_info.rlwe_q().true_el()
1717                    } else {
1718                        bool_evaluator.pbs_info.rlwe_q().false_el()
1719                    };
1720                    let n = measure_noise_lwe(
1721                        &lwe0,
1722                        ideal_client_key.sk_rlwe().values(),
1723                        &bool_evaluator.pbs_info.rlwe_modop,
1724                        &ideal,
1725                    );
1726                    let v = decrypt_lwe(
1727                        &lwe0,
1728                        ideal_client_key.sk_rlwe().values(),
1729                        &bool_evaluator.pbs_info.rlwe_modop,
1730                    );
1731                    (n, v)
1732                };
1733                let noise1 = {
1734                    let ideal = if m1 {
1735                        bool_evaluator.pbs_info.rlwe_q().true_el()
1736                    } else {
1737                        bool_evaluator.pbs_info.rlwe_q().false_el()
1738                    };
1739                    let n = measure_noise_lwe(
1740                        &lwe1,
1741                        ideal_client_key.sk_rlwe().values(),
1742                        &bool_evaluator.pbs_info.rlwe_modop,
1743                        &ideal,
1744                    );
1745                    let v = decrypt_lwe(
1746                        &lwe1,
1747                        ideal_client_key.sk_rlwe().values(),
1748                        &bool_evaluator.pbs_info.rlwe_modop,
1749                    );
1750                    (n, v)
1751                };
1752
1753                // // Trace PBS
1754                // PBSTracer::with_local(|t| {
1755                //     t.trace(
1756                //         &MP_BOOL_PARAMS,
1757                //         &ideal_client_key.sk_lwe.values(),
1758                //         &ideal_client_key.sk_rlwe.values(),
1759                //     )
1760                // });
1761
1762                let noise_out = {
1763                    let ideal_m = if m_expected {
1764                        bool_evaluator.pbs_info.rlwe_q().true_el()
1765                    } else {
1766                        bool_evaluator.pbs_info.rlwe_q().false_el()
1767                    };
1768                    let n = measure_noise_lwe(
1769                        &lwe_out,
1770                        ideal_client_key.sk_rlwe().values(),
1771                        &bool_evaluator.pbs_info.rlwe_modop,
1772                        &ideal_m,
1773                    );
1774                    let v = decrypt_lwe(
1775                        &lwe_out,
1776                        ideal_client_key.sk_rlwe().values(),
1777                        &bool_evaluator.pbs_info.rlwe_modop,
1778                    );
1779                    (n, v)
1780                };
1781                dbg!(m0, m1, m_expected);
1782                println!(
1783                    "ct0 (noise, message): {:?}  \n ct1 (noise, message): {:?} \n PBS (noise, message): {:?}", noise0, noise1, noise_out
1784                );
1785            }
1786
1787            // multi-party decrypt
1788            let decryption_shares = parties
1789                .iter()
1790                .map(|k| bool_evaluator.multi_party_decryption_share(&lwe_out, k))
1791                .collect_vec();
1792            let m_back = bool_evaluator.multi_party_decrypt(&decryption_shares, &lwe_out);
1793
1794            // let m_back = bool_evaluator.sk_decrypt(&lwe_out, &ideal_client_key);
1795
1796            assert!(m_expected == m_back, "Expected {m_expected}, got {m_back}");
1797            m1 = m0;
1798            m0 = m_expected;
1799
1800            lwe1 = lwe0;
1801            lwe0 = lwe_out;
1802        }
1803    }
1804
1805    #[test]
1806    fn noise_tester() {
1807        let bool_evaluator = BoolEvaluator::<
1808            Vec<Vec<u64>>,
1809            NttBackendU64,
1810            ModularOpsU64<CiphertextModulus<u64>>,
1811            ModularOpsU64<CiphertextModulus<u64>>,
1812        >::new(SP_BOOL_PARAMS);
1813
1814        // let (_, collective_pk, _, _, server_key_eval, ideal_client_key) =
1815        //     _multi_party_all_keygen(&bool_evaluator, 20);
1816        let no_of_parties = 2;
1817        let lwe_q = bool_evaluator.pbs_info.parameters.lwe_q();
1818        let rlwe_q = bool_evaluator.pbs_info.parameters.rlwe_q();
1819        let lwe_n = bool_evaluator.pbs_info.parameters.lwe_n().0;
1820        let rlwe_n = bool_evaluator.pbs_info.parameters.rlwe_n().0;
1821        let lwe_modop = &bool_evaluator.pbs_info.lwe_modop;
1822        let rlwe_nttop = &bool_evaluator.pbs_info.rlwe_nttop;
1823        let rlwe_modop = &bool_evaluator.pbs_info.rlwe_modop;
1824
1825        // let rgsw_rgsw_decomposer = &bool_evaluator
1826        //     .pbs_info
1827        //     .parameters
1828        //     .rgsw_rgsw_decomposer::<DefaultDecomposer<u64>>();
1829        // let rgsw_rgsw_gadget_a = rgsw_rgsw_decomposer.0.gadget_vector();
1830        // let rgsw_rgsw_gadget_b = rgsw_rgsw_decomposer.1.gadget_vector();
1831
1832        let rlwe_rgsw_decomposer = &bool_evaluator.pbs_info.rlwe_rgsw_decomposer;
1833        let rlwe_rgsw_gadget_a = rlwe_rgsw_decomposer.0.gadget_vector();
1834        let rlwe_rgsw_gadget_b = rlwe_rgsw_decomposer.1.gadget_vector();
1835
1836        let auto_decomposer = &bool_evaluator.pbs_info.auto_decomposer;
1837        let auto_gadget = auto_decomposer.gadget_vector();
1838
1839        let parties = (0..no_of_parties)
1840            .map(|_| bool_evaluator.client_key())
1841            .collect_vec();
1842
1843        let ideal_client_key = {
1844            let mut ideal_rlwe_sk = vec![0i32; bool_evaluator.pbs_info.rlwe_n()];
1845            parties.iter().for_each(|k| {
1846                izip!(ideal_rlwe_sk.iter_mut(), k.sk_rlwe().values()).for_each(|(ideal_i, s_i)| {
1847                    *ideal_i = *ideal_i + s_i;
1848                });
1849            });
1850            let mut ideal_lwe_sk = vec![0i32; bool_evaluator.pbs_info.lwe_n()];
1851            parties.iter().for_each(|k| {
1852                izip!(ideal_lwe_sk.iter_mut(), k.sk_lwe().values()).for_each(|(ideal_i, s_i)| {
1853                    *ideal_i = *ideal_i + s_i;
1854                });
1855            });
1856
1857            ClientKey::new(
1858                RlweSecret {
1859                    values: ideal_rlwe_sk,
1860                },
1861                LweSecret {
1862                    values: ideal_lwe_sk,
1863                },
1864            )
1865        };
1866
1867        // check noise in freshly encrypted RLWE ciphertext (ie var_fresh)
1868        if true {
1869            let mut rng = DefaultSecureRng::new();
1870            let mut check = Stats { samples: vec![] };
1871            for _ in 0..10 {
1872                // generate a new collective public key
1873                let mut pk_cr_seed = [0u8; 32];
1874                rng.fill_bytes(&mut pk_cr_seed);
1875                let public_key_share = parties
1876                    .iter()
1877                    .map(|k| bool_evaluator.multi_party_public_key_share(pk_cr_seed, k))
1878                    .collect_vec();
1879                let collective_pk = PublicKey::<
1880                    Vec<Vec<u64>>,
1881                    DefaultSecureRng,
1882                    ModularOpsU64<CiphertextModulus<u64>>,
1883                >::from(public_key_share.as_slice());
1884
1885                let mut m = vec![0u64; rlwe_n];
1886                RandomFillUniformInModulus::random_fill(&mut rng, rlwe_q, m.as_mut_slice());
1887                let mut rlwe_ct = vec![vec![0u64; rlwe_n]; 2];
1888                public_key_encrypt_rlwe::<_, _, _, _, i32, _>(
1889                    &mut rlwe_ct,
1890                    collective_pk.key(),
1891                    &m,
1892                    rlwe_modop,
1893                    rlwe_nttop,
1894                    &mut rng,
1895                );
1896
1897                let mut m_back = vec![0u64; rlwe_n];
1898                decrypt_rlwe(
1899                    &rlwe_ct,
1900                    ideal_client_key.sk_rlwe().values(),
1901                    &mut m_back,
1902                    rlwe_nttop,
1903                    rlwe_modop,
1904                );
1905
1906                rlwe_modop.elwise_sub_mut(m_back.as_mut_slice(), m.as_slice());
1907
1908                check.add_more(Vec::<i64>::try_convert_from(&m_back, rlwe_q).as_slice());
1909            }
1910
1911            println!("Public key Std: {}", check.std_dev().abs().log2());
1912        }
1913
1914        if true {
1915            // Generate server key shares
1916            let mut rng = DefaultSecureRng::new();
1917            let mut pk_cr_seed = [0u8; 32];
1918            rng.fill_bytes(&mut pk_cr_seed);
1919            let public_key_share = parties
1920                .iter()
1921                .map(|k| bool_evaluator.multi_party_public_key_share(pk_cr_seed, k))
1922                .collect_vec();
1923            let collective_pk = PublicKey::<
1924                Vec<Vec<u64>>,
1925                DefaultSecureRng,
1926                ModularOpsU64<CiphertextModulus<u64>>,
1927            >::from(public_key_share.as_slice());
1928
1929            let pbs_cr_seed = [0u8; 32];
1930            rng.fill_bytes(&mut pk_cr_seed);
1931            let server_key_shares = parties
1932                .iter()
1933                .map(|k| {
1934                    bool_evaluator.multi_party_server_key_share(pbs_cr_seed, collective_pk.key(), k)
1935                })
1936                .collect_vec();
1937
1938            let seeded_server_key =
1939                bool_evaluator.aggregate_multi_party_server_key_shares(&server_key_shares);
1940
1941            // Check noise in RGSW ciphertexts of ideal LWE secret elements
1942            if false {
1943                let mut check = Stats { samples: vec![] };
1944                izip!(
1945                    ideal_client_key.sk_lwe().values.iter(),
1946                    seeded_server_key.rgsw_cts().iter()
1947                )
1948                .for_each(|(s_i, rgsw_ct_i)| {
1949                    // X^{s[i]}
1950                    let mut m_si = vec![0u64; rlwe_n];
1951                    let s_i = *s_i * (bool_evaluator.pbs_info.embedding_factor as i32);
1952                    if s_i < 0 {
1953                        m_si[rlwe_n - (s_i.abs() as usize)] = rlwe_q.neg_one();
1954                    } else {
1955                        m_si[s_i as usize] = 1;
1956                    }
1957
1958                    // RLWE'(-sm)
1959                    let mut neg_s_eval =
1960                        Vec::<u64>::try_convert_from(ideal_client_key.sk_rlwe().values(), rlwe_q);
1961                    rlwe_modop.elwise_neg_mut(&mut neg_s_eval);
1962                    rlwe_nttop.forward(&mut neg_s_eval);
1963                    for j in 0..rlwe_rgsw_decomposer.a().decomposition_count() {
1964                        // RLWE(B^{j} * -s[X]*X^{s_lwe[i]})
1965
1966                        // -s[X]*X^{s_lwe[i]}*B_j
1967                        let mut m_ideal = m_si.clone();
1968                        rlwe_nttop.forward(m_ideal.as_mut_slice());
1969                        rlwe_modop.elwise_mul_mut(m_ideal.as_mut_slice(), neg_s_eval.as_slice());
1970                        rlwe_nttop.backward(m_ideal.as_mut_slice());
1971                        rlwe_modop
1972                            .elwise_scalar_mul_mut(m_ideal.as_mut_slice(), &rlwe_rgsw_gadget_a[j]);
1973
1974                        // RLWE(-s*X^{s_lwe[i]}*B_j)
1975                        let mut rlwe_ct = vec![vec![0u64; rlwe_n]; 2];
1976                        rlwe_ct[0].copy_from_slice(&rgsw_ct_i[j]);
1977                        rlwe_ct[1].copy_from_slice(
1978                            &rgsw_ct_i[j + rlwe_rgsw_decomposer.a().decomposition_count()],
1979                        );
1980
1981                        let mut m_back = vec![0u64; rlwe_n];
1982                        decrypt_rlwe(
1983                            &rlwe_ct,
1984                            ideal_client_key.sk_rlwe().values(),
1985                            &mut m_back,
1986                            rlwe_nttop,
1987                            rlwe_modop,
1988                        );
1989
1990                        // diff
1991                        rlwe_modop.elwise_sub_mut(&mut m_back, &m_ideal);
1992                        check.add_more(&Vec::<i64>::try_convert_from(&m_back, rlwe_q));
1993                    }
1994
1995                    // RLWE'(m)
1996                    for j in 0..rlwe_rgsw_decomposer.b().decomposition_count() {
1997                        // RLWE(B^{j} * X^{s_lwe[i]})
1998
1999                        // X^{s_lwe[i]}*B_j
2000                        let mut m_ideal = m_si.clone();
2001                        rlwe_modop
2002                            .elwise_scalar_mul_mut(m_ideal.as_mut_slice(), &rlwe_rgsw_gadget_b[j]);
2003
2004                        // RLWE(X^{s_lwe[i]}*B_j)
2005                        let mut rlwe_ct = vec![vec![0u64; rlwe_n]; 2];
2006                        rlwe_ct[0].copy_from_slice(
2007                            &rgsw_ct_i[j + (2 * rlwe_rgsw_decomposer.a().decomposition_count())],
2008                        );
2009                        rlwe_ct[1].copy_from_slice(
2010                            &rgsw_ct_i[j
2011                                + (2 * rlwe_rgsw_decomposer.a().decomposition_count()
2012                                    + rlwe_rgsw_decomposer.b().decomposition_count())],
2013                        );
2014
2015                        let mut m_back = vec![0u64; rlwe_n];
2016                        decrypt_rlwe(
2017                            &rlwe_ct,
2018                            ideal_client_key.sk_rlwe().values(),
2019                            &mut m_back,
2020                            rlwe_nttop,
2021                            rlwe_modop,
2022                        );
2023
2024                        // diff
2025                        rlwe_modop.elwise_sub_mut(&mut m_back, &m_ideal);
2026                        check.add_more(&Vec::<i64>::try_convert_from(&m_back, rlwe_q));
2027                    }
2028                });
2029                println!(
2030                    "RGSW Std: {} {} ;; max={}",
2031                    check.mean(),
2032                    check.std_dev().abs().log2(),
2033                    check.samples.iter().max().unwrap()
2034                );
2035            }
2036
2037            // server key in Evaluation domain
2038            let server_key_eval_domain =
2039                ServerKeyEvaluationDomain::<_, DefaultSecureRng, NttBackendU64>::from(
2040                    &seeded_server_key,
2041                );
2042
2043            // check noise in RLWE x RGSW(X^{s_i}) where RGSW is accunulated RGSW ciphertext
2044            if false {
2045                let mut check = Stats { samples: vec![] };
2046
2047                izip!(
2048                    ideal_client_key.sk_lwe().values(),
2049                    server_key_eval_domain.rgsw_cts().iter()
2050                )
2051                .for_each(|(s_i, rgsw_ct_i)| {
2052                    let mut m = vec![0u64; rlwe_n];
2053                    RandomFillUniformInModulus::random_fill(&mut rng, rlwe_q, m.as_mut_slice());
2054                    let mut rlwe_ct = vec![vec![0u64; rlwe_n]; 2];
2055                    public_key_encrypt_rlwe::<_, _, _, _, i32, _>(
2056                        &mut rlwe_ct,
2057                        collective_pk.key(),
2058                        &m,
2059                        rlwe_modop,
2060                        rlwe_nttop,
2061                        &mut rng,
2062                    );
2063
2064                    // RLWE(m*X^{s[i]}) = RLWE(m) x RGSW(X^{s[i]})
2065                    // let mut rlwe_after = RlweCiphertext::<_, DefaultSecureRng>::new_trivial(vec![
2066                    //     vec![0u64; rlwe_n],
2067                    //     m.clone(),
2068                    // ]);
2069                    let mut rlwe_after = RlweCiphertext::<_, DefaultSecureRng> {
2070                        data: rlwe_ct.clone(),
2071                        is_trivial: false,
2072                        _phatom: PhantomData,
2073                    };
2074                    let mut scratch = vec![
2075                        vec![0u64; rlwe_n];
2076                        std::cmp::max(
2077                            rlwe_rgsw_decomposer.0.decomposition_count(),
2078                            rlwe_rgsw_decomposer.1.decomposition_count()
2079                        ) + 2
2080                    ];
2081                    rlwe_by_rgsw(
2082                        &mut rlwe_after,
2083                        rgsw_ct_i,
2084                        &mut scratch,
2085                        rlwe_rgsw_decomposer,
2086                        rlwe_nttop,
2087                        rlwe_modop,
2088                    );
2089
2090                    // m1 = X^{s[i]}
2091                    let mut m1 = vec![0u64; rlwe_n];
2092                    let s_i = *s_i * (bool_evaluator.pbs_info.embedding_factor as i32);
2093                    if s_i < 0 {
2094                        m1[rlwe_n - (s_i.abs() as usize)] = rlwe_q.neg_one()
2095                    } else {
2096                        m1[s_i as usize] = 1;
2097                    }
2098
2099                    // (m+e) * m1
2100                    let mut m_plus_e_times_m1 = vec![0u64; rlwe_n];
2101                    decrypt_rlwe(
2102                        &rlwe_ct,
2103                        ideal_client_key.sk_rlwe().values(),
2104                        &mut m_plus_e_times_m1,
2105                        rlwe_nttop,
2106                        rlwe_modop,
2107                    );
2108                    rlwe_nttop.forward(m_plus_e_times_m1.as_mut_slice());
2109                    rlwe_nttop.forward(m1.as_mut_slice());
2110                    rlwe_modop.elwise_mul_mut(m_plus_e_times_m1.as_mut_slice(), m1.as_slice());
2111                    rlwe_nttop.backward(m_plus_e_times_m1.as_mut_slice());
2112
2113                    // Resulting RLWE ciphertext will equal: (m0m1 + em1) + e_{rlsw x rgsw}.
2114                    // Hence, resulting rlwe ciphertext will have error em1 + e_{rlwe x rgsw}.
2115                    // Here we're only concerned with e_{rlwe x rgsw}, that is noise added by
2116                    // RLWExRGSW. Also note in practice m1 is a monomial, for ex, X^{s_{i}}, for
2117                    // some i and var(em1) = var(e).
2118                    let mut m_plus_e_times_m1_more_e = vec![0u64; rlwe_n];
2119                    decrypt_rlwe(
2120                        &rlwe_after,
2121                        ideal_client_key.sk_rlwe().values(),
2122                        &mut m_plus_e_times_m1_more_e,
2123                        rlwe_nttop,
2124                        rlwe_modop,
2125                    );
2126
2127                    // diff
2128                    rlwe_modop.elwise_sub_mut(
2129                        m_plus_e_times_m1_more_e.as_mut_slice(),
2130                        m_plus_e_times_m1.as_slice(),
2131                    );
2132
2133                    // let noise = measure_noise(
2134                    //     &rlwe_after,
2135                    //     &m_plus_e_times_m1,
2136                    //     rlwe_nttop,
2137                    //     rlwe_modop,
2138                    //     ideal_client_key.sk_rlwe.values(),
2139                    // );
2140                    // print!("NOISE: {}", noise);
2141
2142                    check.add_more(&Vec::<i64>::try_convert_from(
2143                        &m_plus_e_times_m1_more_e,
2144                        rlwe_q,
2145                    ));
2146                });
2147                println!(
2148                    "RLWE x RGSW, where RGSW has noise var_brk, std: {} {}",
2149                    check.std_dev(),
2150                    check.std_dev().abs().log2()
2151                )
2152            }
2153
2154            // check noise in Auto key
2155            if false {
2156                let mut check = Stats { samples: vec![] };
2157
2158                let mut neg_s_poly =
2159                    Vec::<u64>::try_convert_from(ideal_client_key.sk_rlwe().values(), rlwe_q);
2160                rlwe_modop.elwise_neg_mut(neg_s_poly.as_mut_slice());
2161
2162                let g = bool_evaluator.pbs_info.g();
2163                let br_q = bool_evaluator.pbs_info.br_q();
2164                let auto_element_dlogs = bool_evaluator.pbs_info.parameters.auto_element_dlogs();
2165                for i in auto_element_dlogs.into_iter() {
2166                    let g_pow = if i == 0 {
2167                        -g
2168                    } else {
2169                        (((g as usize).pow(i as u32)) % br_q) as isize
2170                    };
2171
2172                    // -s[X^k]
2173                    let (auto_indices, auto_sign) = generate_auto_map(rlwe_n, g_pow);
2174                    let mut neg_s_poly_auto_i = vec![0u64; rlwe_n];
2175                    izip!(neg_s_poly.iter(), auto_indices.iter(), auto_sign.iter()).for_each(
2176                        |(v, to_i, to_sign)| {
2177                            if !to_sign {
2178                                neg_s_poly_auto_i[*to_i] = rlwe_modop.neg(v);
2179                            } else {
2180                                neg_s_poly_auto_i[*to_i] = *v;
2181                            }
2182                        },
2183                    );
2184
2185                    let mut auto_key_i = server_key_eval_domain.galois_key_for_auto(i).clone();
2186                    // send i^th auto key to coefficient domain
2187                    auto_key_i
2188                        .iter_mut()
2189                        .for_each(|r| rlwe_nttop.backward(r.as_mut_slice()));
2190                    auto_gadget.iter().enumerate().for_each(|(i, b_i)| {
2191                        // B^i * -s[X^k]
2192                        let mut m_ideal = neg_s_poly_auto_i.clone();
2193                        rlwe_modop.elwise_scalar_mul_mut(m_ideal.as_mut_slice(), b_i);
2194
2195                        let mut m_out = vec![0u64; rlwe_n];
2196                        let mut rlwe_ct = vec![vec![0u64; rlwe_n]; 2];
2197                        rlwe_ct[0].copy_from_slice(&auto_key_i[i]);
2198                        rlwe_ct[1].copy_from_slice(
2199                            &auto_key_i[auto_decomposer.decomposition_count() + i],
2200                        );
2201                        decrypt_rlwe(
2202                            &rlwe_ct,
2203                            ideal_client_key.sk_rlwe().values(),
2204                            &mut m_out,
2205                            rlwe_nttop,
2206                            rlwe_modop,
2207                        );
2208
2209                        // diff
2210                        rlwe_modop.elwise_sub_mut(m_out.as_mut_slice(), m_ideal.as_slice());
2211
2212                        check.add_more(&Vec::<i64>::try_convert_from(&m_out, rlwe_q));
2213                    });
2214                }
2215
2216                println!("Auto key noise std dev: {}", check.std_dev().abs().log2());
2217            }
2218
2219            // check noise in RLWE(X^k) after sending RLWE(X) -> RLWE(X^k) using collective
2220            // auto key
2221            if true {
2222                let mut check = Stats { samples: vec![] };
2223                let br_q = bool_evaluator.pbs_info.br_q();
2224                let g = bool_evaluator.pbs_info.g();
2225                let auto_element_dlogs = bool_evaluator.pbs_info.parameters.auto_element_dlogs();
2226                for i in auto_element_dlogs.into_iter() {
2227                    for _ in 0..10 {
2228                        let mut m = vec![0u64; rlwe_n];
2229                        RandomFillUniformInModulus::random_fill(&mut rng, rlwe_q, m.as_mut_slice());
2230                        let mut rlwe_ct = RlweCiphertext::<_, DefaultSecureRng> {
2231                            data: vec![vec![0u64; rlwe_n]; 2],
2232                            is_trivial: false,
2233                            _phatom: PhantomData,
2234                        };
2235                        public_key_encrypt_rlwe::<_, _, _, _, i32, _>(
2236                            &mut rlwe_ct,
2237                            collective_pk.key(),
2238                            &m,
2239                            rlwe_modop,
2240                            rlwe_nttop,
2241                            &mut rng,
2242                        );
2243
2244                        // We're only interested in noise increased as a result of automorphism.
2245                        // Hence, we take m+e as the bench.
2246                        let mut m_plus_e = vec![0u64; rlwe_n];
2247                        decrypt_rlwe(
2248                            &rlwe_ct,
2249                            ideal_client_key.sk_rlwe().values(),
2250                            &mut m_plus_e,
2251                            rlwe_nttop,
2252                            rlwe_modop,
2253                        );
2254
2255                        let auto_key = server_key_eval_domain.galois_key_for_auto(i);
2256                        let (auto_map_index, auto_map_sign) =
2257                            bool_evaluator.pbs_info.rlwe_auto_map(i);
2258                        let mut scratch =
2259                            vec![vec![0u64; rlwe_n]; auto_decomposer.decomposition_count() + 2];
2260                        galois_auto(
2261                            &mut rlwe_ct,
2262                            auto_key,
2263                            &mut scratch,
2264                            &auto_map_index,
2265                            &auto_map_sign,
2266                            rlwe_modop,
2267                            rlwe_nttop,
2268                            auto_decomposer,
2269                        );
2270
2271                        // send m+e from X to X^k
2272                        let mut m_plus_e_auto = vec![0u64; rlwe_n];
2273                        izip!(m_plus_e.iter(), auto_map_index.iter(), auto_map_sign.iter())
2274                            .for_each(|(v, to_index, to_sign)| {
2275                                if !to_sign {
2276                                    m_plus_e_auto[*to_index] = rlwe_modop.neg(v);
2277                                } else {
2278                                    m_plus_e_auto[*to_index] = *v
2279                                }
2280                            });
2281
2282                        let mut m_out = vec![0u64; rlwe_n];
2283                        decrypt_rlwe(
2284                            &rlwe_ct,
2285                            ideal_client_key.sk_rlwe().values(),
2286                            &mut m_out,
2287                            rlwe_nttop,
2288                            rlwe_modop,
2289                        );
2290
2291                        // diff
2292                        rlwe_modop.elwise_sub_mut(m_out.as_mut_slice(), m_plus_e_auto.as_slice());
2293
2294                        check.add_more(&Vec::<i64>::try_convert_from(m_out.as_slice(), rlwe_q));
2295                    }
2296                }
2297
2298                println!("Rlwe Auto Noise Std: {}", check.std_dev().abs().log2());
2299            }
2300
2301            // Check noise growth in ksk
2302            // TODO check in LWE key switching keys
2303            if true {
2304                // 1. encrypt LWE ciphertext
2305                // 2. Key switching
2306                // 3.
2307                let mut check = Stats { samples: vec![] };
2308
2309                for _ in 0..1024 {
2310                    // Encrypt m \in Q_{ks} using RLWE sk
2311                    let mut lwe_in_ct = vec![0u64; rlwe_n + 1];
2312                    let m = RandomElementInModulus::random(&mut rng, &lwe_q.q().unwrap());
2313                    encrypt_lwe(
2314                        &mut lwe_in_ct,
2315                        &m,
2316                        ideal_client_key.sk_rlwe().values(),
2317                        lwe_modop,
2318                        &mut rng,
2319                    );
2320
2321                    // Key switch
2322                    let mut lwe_out = vec![0u64; lwe_n + 1];
2323                    lwe_key_switch(
2324                        &mut lwe_out,
2325                        &lwe_in_ct,
2326                        server_key_eval_domain.lwe_ksk(),
2327                        lwe_modop,
2328                        bool_evaluator.pbs_info.lwe_decomposer(),
2329                    );
2330
2331                    // We only care about noise added by LWE key switch
2332                    // m+e
2333                    let m_plus_e =
2334                        decrypt_lwe(&lwe_in_ct, ideal_client_key.sk_rlwe().values(), lwe_modop);
2335
2336                    let m_plus_e_plus_lwe_ksk_noise =
2337                        decrypt_lwe(&lwe_out, ideal_client_key.sk_lwe().values(), lwe_modop);
2338
2339                    let diff = lwe_modop.sub(&m_plus_e_plus_lwe_ksk_noise, &m_plus_e);
2340
2341                    check.add_more(&vec![lwe_q.map_element_to_i64(&diff)]);
2342                }
2343
2344                println!("Lwe ksk std dev: {}", check.std_dev().abs().log2());
2345            }
2346        }
2347
2348        // Check noise in fresh RGSW ciphertexts, ie X^{s_j[i]}, must equal noise in
2349        // fresh RLWE ciphertext
2350        if true {}
2351        // test LWE ksk from RLWE -> LWE
2352        // if false {
2353        //     let logp = 2;
2354        //     let mut rng = DefaultSecureRng::new();
2355
2356        //     let m = 1;
2357        //     let encoded_m = m << (lwe_logq - logp);
2358
2359        //     // Encrypt
2360        //     let mut lwe_ct = vec![0u64; rlwe_n + 1];
2361        //     encrypt_lwe(
2362        //         &mut lwe_ct,
2363        //         &encoded_m,
2364        //         ideal_client_key.sk_rlwe.values(),
2365        //         lwe_modop,
2366        //         &mut rng,
2367        //     );
2368
2369        //     // key switch
2370        //     let lwe_decomposer = &bool_evaluator.decomposer_lwe;
2371        //     let mut lwe_out = vec![0u64; lwe_n + 1];
2372        //     lwe_key_switch(
2373        //         &mut lwe_out,
2374        //         &lwe_ct,
2375        //         &server_key_eval.lwe_ksk,
2376        //         lwe_modop,
2377        //         lwe_decomposer,
2378        //     );
2379
2380        //     let encoded_m_back = decrypt_lwe(&lwe_out,
2381        // ideal_client_key.sk_lwe.values(), lwe_modop);     let m_back
2382        // =         ((encoded_m_back as f64 * (1 << logp) as f64) /
2383        // (lwe_q as f64)).round() as u64;     dbg!(m_back, m);
2384
2385        //     let noise = measure_noise_lwe(
2386        //         &lwe_out,
2387        //         ideal_client_key.sk_lwe.values(),
2388        //         lwe_modop,
2389        //         &encoded_m,
2390        //     );
2391
2392        //     println!("Noise: {noise}");
2393        // }
2394
2395        // Measure noise in RGSW ciphertexts of ideal LWE secrets
2396        // if true {
2397        //     let gadget_vec = gadget_vector(
2398        //         bool_evaluator.parameters.rlwe_logq,
2399        //         bool_evaluator.parameters.logb_rgsw,
2400        //         bool_evaluator.parameters.d_rgsw,
2401        //     );
2402
2403        //     for i in 0..20 {
2404        //         // measure noise in RGSW(s[i])
2405        //         let si =
2406        //             ideal_client_key.sk_lwe.values[i] *
2407        // (bool_evaluator.embedding_factor as i32);         let mut
2408        // si_poly = vec![0u64; rlwe_n];         if si < 0 {
2409        //             si_poly[rlwe_n - (si.abs() as usize)] = rlwe_q - 1;
2410        //         } else {
2411        //             si_poly[(si.abs() as usize)] = 1;
2412        //         }
2413
2414        //         let mut rgsw_si = server_key_eval.rgsw_cts[i].clone();
2415        //         rgsw_si
2416        //             .iter_mut()
2417        //             .for_each(|ri| rlwe_nttop.backward(ri.as_mut()));
2418
2419        //         println!("####### Noise in RGSW(X^s_{i}) #######");
2420        //         _measure_noise_rgsw(
2421        //             &rgsw_si,
2422        //             &si_poly,
2423        //             ideal_client_key.sk_rlwe.values(),
2424        //             &gadget_vec,
2425        //             rlwe_q,
2426        //         );
2427        //         println!("####### ##################### #######");
2428        //     }
2429        // }
2430
2431        // // measure noise grwoth in RLWExRGSW
2432        // if true {
2433        //     let mut rng = DefaultSecureRng::new();
2434        //     let mut carry_m = vec![0u64; rlwe_n];
2435        //     RandomUniformDist1::random_fill(&mut rng, &rlwe_q,
2436        // carry_m.as_mut_slice());
2437
2438        //     // RGSW(carrym)
2439        //     let trivial_rlwect = vec![vec![0u64; rlwe_n], carry_m.clone()];
2440        //     let mut rlwe_ct = RlweCiphertext::<_,
2441        // DefaultSecureRng>::from_raw(trivial_rlwect, true);
2442
2443        //     let mut scratch_matrix_dplus2_ring = vec![vec![0u64; rlwe_n];
2444        // d_rgsw + 2];     let mul_mod =
2445        //         |v0: &u64, v1: &u64| (((*v0 as u128 * *v1 as u128) % (rlwe_q as u128)) as u64);
2446
2447        //     for i in 0..bool_evaluator.parameters.lwe_n {
2448        //         rlwe_by_rgsw(
2449        //             &mut rlwe_ct,
2450        //             server_key_eval.rgsw_ct_lwe_si(i),
2451        //             &mut scratch_matrix_dplus2_ring,
2452        //             rlwe_decomposer,
2453        //             rlwe_nttop,
2454        //             rlwe_modop,
2455        //         );
2456
2457        //         // carry_m[X] * s_i[X]
2458        //         let si =
2459        //             ideal_client_key.sk_lwe.values[i] *
2460        // (bool_evaluator.embedding_factor as i32);         let mut
2461        // si_poly = vec![0u64; rlwe_n];         if si < 0 {
2462        //             si_poly[rlwe_n - (si.abs() as usize)] = rlwe_q - 1;
2463        //         } else {
2464        //             si_poly[(si.abs() as usize)] = 1;
2465        //         }
2466        //         carry_m = negacyclic_mul(&carry_m, &si_poly, mul_mod,
2467        // rlwe_q);
2468
2469        //         let noise = measure_noise(
2470        //             &rlwe_ct,
2471        //             &carry_m,
2472        //             rlwe_nttop,
2473        //             rlwe_modop,
2474        //             ideal_client_key.sk_rlwe.values(),
2475        //         );
2476        //         println!("Noise RLWE(carry_m) accumulating {i}^th secret
2477        // monomial: {noise}");     }
2478        // }
2479
2480        // // Check galois keys
2481        // if false {
2482        //     let g = bool_evaluator.g() as isize;
2483        //     let mut rng = DefaultSecureRng::new();
2484        //     let mut scratch_matrix_dplus2_ring = vec![vec![0u64; rlwe_n];
2485        // d_rgsw + 2];     for i in [g, -g] {
2486        //         let mut m = vec![0u64; rlwe_n];
2487        //         RandomUniformDist1::random_fill(&mut rng, &rlwe_q,
2488        // m.as_mut_slice());         let mut rlwe_ct = {
2489        //             let mut data = vec![vec![0u64; rlwe_n]; 2];
2490        //             public_key_encrypt_rlwe(
2491        //                 &mut data,
2492        //                 &collective_pk.key,
2493        //                 &m,
2494        //                 rlwe_modop,
2495        //                 rlwe_nttop,
2496        //                 &mut rng,
2497        //             );
2498        //             RlweCiphertext::<_, DefaultSecureRng>::from_raw(data,
2499        // false)         };
2500
2501        //         let auto_key = server_key_eval.galois_key_for_auto(i);
2502        //         let (auto_map_index, auto_map_sign) =
2503        // generate_auto_map(rlwe_n, i);         galois_auto(
2504        //             &mut rlwe_ct,
2505        //             auto_key,
2506        //             &mut scratch_matrix_dplus2_ring,
2507        //             &auto_map_index,
2508        //             &auto_map_sign,
2509        //             rlwe_modop,
2510        //             rlwe_nttop,
2511        //             rlwe_decomposer,
2512        //         );
2513
2514        //         // send m(X) -> m(X^i)
2515        //         let mut m_k = vec![0u64; rlwe_n];
2516        //         izip!(m.iter(), auto_map_index.iter(),
2517        // auto_map_sign.iter()).for_each(             |(mi, to_index, to_sign)|
2518        // {                 if !to_sign {
2519        //                     m_k[*to_index] = rlwe_q - *mi;
2520        //                 } else {
2521        //                     m_k[*to_index] = *mi;
2522        //                 }
2523        //             },
2524        //         );
2525
2526        //         // measure noise
2527        //         let noise = measure_noise(
2528        //             &rlwe_ct,
2529        //             &m_k,
2530        //             rlwe_nttop,
2531        //             rlwe_modop,
2532        //             ideal_client_key.sk_rlwe.values(),
2533        //         );
2534
2535        //         println!("Noise after auto k={i}: {noise}");
2536        //     }
2537        // }
2538    }
2539}