wip rlwe + some bug fixes in base2k

rlwe/examples/encryption.rs

@@ -0,0 +1,77 @@
+use base2k::{Encoding, FFT64, SvpPPolOps};
+use rlwe::{
+    ciphertext::Ciphertext,
+    decryptor::{Decryptor, decrypt_rlwe_thread_safe_tmp_byte},
+    encryptor::{EncryptorSk, encrypt_rlwe_sk_tmp_bytes},
+    keys::SecretKey,
+    parameters::{Parameters, ParametersLiteral},
+    plaintext::Plaintext,
+};
+use sampling::source::{Source, new_seed};
+
+fn main() {
+    let params_lit: ParametersLiteral = ParametersLiteral {
+        log_n: 10,
+        log_q: 54,
+        log_p: 0,
+        log_base2k: 17,
+        log_scale: 20,
+        xe: 3.2,
+        xs: 128,
+    };
+
+    let params: Parameters = Parameters::new::<FFT64>(&params_lit);
+
+    let mut tmp_bytes: Vec<u8> = vec![
+        0u8;
+        params.decrypt_rlwe_thread_safe_tmp_byte(params.log_q())
+            | params.encrypt_rlwe_sk_tmp_bytes(params.log_q())
+    ];
+
+    let sk: SecretKey = SecretKey::new(params.module());
+
+    let mut want = vec![i64::default(); params.n()];
+
+    want.iter_mut().enumerate().for_each(|(i, x)| *x = i as i64);
+
+    let mut pt: Plaintext = params.new_plaintext(params.log_q() - 20);
+
+    let log_base2k = pt.log_base2k();
+
+    let log_k: usize = 17;
+
+    pt.0.value[0].encode_vec_i64(log_base2k, log_k, &want, 32);
+    pt.0.value[0].normalize(log_base2k, &mut tmp_bytes);
+
+    println!("log_k: {}", log_k);
+    pt.0.value[0].print_limbs(pt.limbs(), 16);
+
+    let mut ct: Ciphertext = params.new_ciphertext(params.log_q());
+
+    let mut source_xe: Source = Source::new(new_seed());
+    let mut source_xa: Source = Source::new(new_seed());
+
+    let mut sk_svp_ppol: base2k::SvpPPol = params.module().svp_new_ppol();
+    params.module().svp_prepare(&mut sk_svp_ppol, &sk.0);
+
+    params.encrypt_rlwe_sk_thread_safe(
+        &mut ct,
+        Some(&pt),
+        &sk_svp_ppol,
+        &mut source_xa,
+        &mut source_xe,
+        &mut tmp_bytes,
+    );
+
+    params.decrypt_rlwe_thread_safe(&mut pt, &ct, &sk_svp_ppol, &mut tmp_bytes);
+
+    pt.0.value[0].print_limbs(pt.limbs(), 16);
+
+    let mut have = vec![i64::default(); params.n()];
+
+    println!("pt: {}", log_k);
+    pt.0.value[0].decode_vec_i64(pt.log_base2k(), log_k, &mut have);
+
+    println!("want: {:?}", &want[..16]);
+    println!("have: {:?}", &have[..16]);
+}

rlwe/src/ciphertext.rs

@@ -1,20 +1,19 @@
 use crate::elem::Elem;
+use crate::parameters::Parameters;
 use crate::plaintext::Plaintext;
-use base2k::VecZnx;
+use base2k::{Module, VecZnx, VmpPMat, VmpPMatOps};
 
 pub struct Ciphertext(pub Elem);
 
-/*
-impl Parameters {
-    pub fn new_ciphertext(&self, degree: usize, log_base2k: usize, log_q: usize) -> Ciphertext {
-        Ciphertext(self.new_elem(degree, log_base2k, log_q))
-    }
-}
- */
-
 impl Ciphertext {
-    pub fn new(n: usize, log_base2k: usize, log_q: usize, degree: usize) -> Self {
-        Self(Elem::new(n, log_base2k, log_q, degree))
+    pub fn new(
+        module: &Module,
+        log_base2k: usize,
+        log_q: usize,
+        degree: usize,
+        log_scale: usize,
+    ) -> Self {
+        Self(Elem::new(module, log_base2k, log_q, degree, log_scale))
     }
 
     pub fn n(&self) -> usize {
@@ -45,7 +44,75 @@ impl Ciphertext {
         self.0.log_base2k()
     }
 
+    pub fn log_scale(&self) -> usize {
+        self.0.log_scale
+    }
+
     pub fn as_plaintext(&self) -> Plaintext {
         unsafe { Plaintext(std::ptr::read(&self.0)) }
     }
 }
+
+impl Parameters {
+    pub fn new_ciphertext(&self, log_q: usize) -> Ciphertext {
+        Ciphertext::new(self.module(), self.log_base2k(), log_q, self.log_scale(), 1)
+    }
+}
+
+pub struct GadgetCiphertext {
+    pub value: Vec<VmpPMat>,
+    pub log_base2k: usize,
+    pub log_q: usize,
+    pub log_scale: usize,
+}
+
+impl GadgetCiphertext {
+    pub fn new(
+        module: &Module,
+        log_base2k: usize,
+        rows: usize,
+        log_q: usize,
+        log_scale: usize,
+    ) -> Self {
+        let cols: usize = (log_q + log_base2k - 1) / log_base2k;
+        let mut value: Vec<VmpPMat> = Vec::new();
+        (0..rows).for_each(|_| value.push(module.new_vmp_pmat(rows, cols)));
+        Self {
+            value,
+            log_base2k,
+            log_q,
+            log_scale,
+        }
+    }
+
+    pub fn n(&self) -> usize {
+        self.value[0].n
+    }
+
+    pub fn rows(&self) -> usize {
+        self.value[0].rows
+    }
+
+    pub fn cols(&self) -> usize {
+        self.value[0].cols
+    }
+
+    pub fn degree(&self) -> usize {
+        self.value.len() - 1
+    }
+
+    pub fn log_q(&self) -> usize {
+        self.log_q
+    }
+
+    pub fn log_base2k(&self) -> usize {
+        self.log_base2k
+    }
+}
+
+pub struct RGSWCiphertext {
+    pub value: [GadgetCiphertext; 2],
+    pub log_base2k: usize,
+    pub log_q: usize,
+    pub log_p: usize,
+}

rlwe/src/decryptor.rs

@@ -0,0 +1,80 @@
+use crate::{
+    ciphertext::Ciphertext, keys::SecretKey, parameters::Parameters, plaintext::Plaintext,
+};
+use base2k::{Module, SvpPPol, SvpPPolOps, VecZnxDft};
+use std::cmp::min;
+
+pub struct Decryptor {
+    sk: SvpPPol,
+}
+
+impl Decryptor {
+    pub fn new(params: &Parameters, sk: &SecretKey) -> Self {
+        let mut sk_svp_ppol: SvpPPol = params.module().svp_new_ppol();
+        sk.prepare(params.module(), &mut sk_svp_ppol);
+        Self { sk: sk_svp_ppol }
+    }
+}
+
+pub fn decrypt_rlwe_thread_safe_tmp_byte(module: &Module, limbs: usize) -> usize {
+    module.bytes_of_vec_znx_dft(limbs) + module.vec_znx_big_normalize_tmp_bytes()
+}
+
+impl Parameters {
+    pub fn decrypt_rlwe_thread_safe_tmp_byte(&self, log_q: usize) -> usize {
+        decrypt_rlwe_thread_safe_tmp_byte(
+            self.module(),
+            (log_q + self.log_base2k() - 1) / self.log_base2k(),
+        )
+    }
+
+    pub fn decrypt_rlwe_thread_safe(
+        &self,
+        res: &mut Plaintext,
+        ct: &Ciphertext,
+        sk: &SvpPPol,
+        tmp_bytes: &mut [u8],
+    ) {
+        decrypt_rlwe_thread_safe(self.module(), res, ct, sk, tmp_bytes)
+    }
+}
+
+pub fn decrypt_rlwe_thread_safe(
+    module: &Module,
+    res: &mut Plaintext,
+    ct: &Ciphertext,
+    sk: &SvpPPol,
+    tmp_bytes: &mut [u8],
+) {
+    let limbs: usize = min(res.limbs(), ct.limbs());
+
+    assert!(
+        tmp_bytes.len() >= decrypt_rlwe_thread_safe_tmp_byte(module, limbs),
+        "invalid tmp_bytes: tmp_bytes.len()={} < decrypt_rlwe_thread_safe_tmp_byte={}",
+        tmp_bytes.len(),
+        decrypt_rlwe_thread_safe_tmp_byte(module, limbs)
+    );
+
+    let res_dft_bytes: usize = module.bytes_of_vec_znx_dft(limbs);
+
+    let mut res_dft: VecZnxDft = VecZnxDft::from_bytes(limbs, tmp_bytes);
+    let mut res_big: base2k::VecZnxBig = res_dft.as_vec_znx_big();
+
+    // res_dft <- DFT(ct[1]) * DFT(sk)
+    module.svp_apply_dft(&mut res_dft, sk, &ct.0.value[1], limbs);
+    // res_big <- ct[1] x sk
+    module.vec_znx_idft_tmp_a(&mut res_big, &mut res_dft, limbs);
+    // res_big <- ct[1] x sk + ct[0]
+    module.vec_znx_big_add_small_inplace(&mut res_big, &ct.0.value[0], limbs);
+    // res <- normalize(ct[1] x sk + ct[0])
+    module.vec_znx_big_normalize(
+        ct.log_base2k(),
+        res.at_mut(0),
+        &res_big,
+        &mut tmp_bytes[res_dft_bytes..],
+    );
+
+    res.0.log_base2k = ct.log_base2k();
+    res.0.log_q = min(res.log_q(), ct.log_q());
+    res.0.log_scale = ct.log_scale();
+}

rlwe/src/elem.rs

@@ -1,21 +1,59 @@
 use crate::parameters::Parameters;
-use base2k::{Infos, VecZnx};
+use base2k::{Infos, Module, VecZnx, VecZnxOps};
 
 pub struct Elem {
     pub value: Vec<VecZnx>,
     pub log_base2k: usize,
     pub log_q: usize,
+    pub log_scale: usize,
 }
 
 impl Elem {
-    pub fn new(n: usize, log_base2k: usize, log_q: usize, degree: usize) -> Self {
+    pub fn new(
+        module: &Module,
+        log_base2k: usize,
+        log_q: usize,
+        degree: usize,
+        log_scale: usize,
+    ) -> Self {
         let limbs: usize = (log_q + log_base2k - 1) / log_base2k;
         let mut value: Vec<VecZnx> = Vec::new();
-        (0..degree + 1).for_each(|_| value.push(VecZnx::new(n, limbs)));
+        (0..degree + 1).for_each(|_| value.push(module.new_vec_znx(limbs)));
         Self {
             value,
-            log_base2k,
             log_q,
+            log_base2k,
+            log_scale: log_scale,
+        }
+    }
+
+    pub fn bytes_of(module: &Module, log_base2k: usize, log_q: usize, degree: usize) -> usize {
+        let cols = (log_q + log_base2k - 1) / log_base2k;
+        module.n() * cols * (degree + 1) * 8
+    }
+
+    pub fn from_bytes(
+        module: &Module,
+        log_base2k: usize,
+        log_q: usize,
+        degree: usize,
+        bytes: &mut [u8],
+    ) -> Self {
+        let n: usize = module.n();
+        assert!(bytes.len() >= Self::bytes_of(module, log_base2k, log_q, degree));
+        let mut value: Vec<VecZnx> = Vec::new();
+        let limbs: usize = (log_q + log_base2k - 1) / log_base2k;
+        let size = VecZnx::bytes(n, limbs);
+        let mut ptr: usize = 0;
+        (0..degree + 1).for_each(|_| {
+            value.push(VecZnx::from_bytes(n, limbs, &mut bytes[ptr..]));
+            ptr += size
+        });
+        Self {
+            value,
+            log_q,
+            log_base2k,
+            log_scale: 0,
         }
     }
 
@@ -35,6 +73,10 @@ impl Elem {
         self.log_base2k
     }
 
+    pub fn log_scale(&self) -> usize {
+        self.log_scale
+    }
+
     pub fn log_q(&self) -> usize {
         self.log_q
     }
@@ -49,3 +91,13 @@ impl Elem {
         &mut self.value[i]
     }
 }
+
+impl Parameters {
+    pub fn bytes_of_elem(&self, log_q: usize, degree: usize) -> usize {
+        Elem::bytes_of(self.module(), self.log_base2k(), log_q, degree)
+    }
+
+    pub fn elem_from_bytes(&self, log_q: usize, degree: usize, bytes: &mut [u8]) -> Elem {
+        Elem::from_bytes(self.module(), self.log_base2k(), log_q, degree, bytes)
+    }
+}

rlwe/src/encryptor.rs

@@ -1,84 +1,141 @@
-use crate::ciphertext::Ciphertext;
+use crate::ciphertext::{Ciphertext, GadgetCiphertext};
 use crate::elem::Elem;
 use crate::keys::SecretKey;
 use crate::parameters::Parameters;
 use crate::plaintext::Plaintext;
+use base2k::ffi::znx::znx_zero_i64_ref;
 use base2k::sampling::Sampling;
-use base2k::{Module, SvpPPol, SvpPPolOps, VecZnx, VecZnxBig, VecZnxDft};
-use sampling::source::Source;
+use base2k::{
+    Module, Scalar, SvpPPol, SvpPPolOps, VecZnx, VecZnxBig, VecZnxDft, VecZnxOps, VmpPMatOps,
+};
+use sampling::source::{Source, new_seed};
 
 pub struct EncryptorSk {
-    pub sk: SvpPPol,
+    sk: SvpPPol,
+    source_xa: Source,
+    source_xe: Source,
+    initialized: bool,
+    tmp_bytes: Vec<u8>,
 }
 
 impl EncryptorSk {
-    pub fn new(params: &Parameters, sk: &SecretKey) -> Self {
+    pub fn new(params: &Parameters, sk: Option<&SecretKey>) -> Self {
         let mut sk_svp_ppol: SvpPPol = params.module().svp_new_ppol();
-        params.module().svp_prepare(&mut sk_svp_ppol, &sk.0);
-        Self { sk: sk_svp_ppol }
+        let mut initialized: bool = false;
+        if let Some(sk) = sk {
+            sk.prepare(params.module(), &mut sk_svp_ppol);
+            initialized = true;
+        }
+        Self {
+            sk: sk_svp_ppol,
+            initialized,
+            source_xa: Source::new(new_seed()),
+            source_xe: Source::new(new_seed()),
+            tmp_bytes: vec![0u8; params.encrypt_rlwe_sk_tmp_bytes(params.limbs_qp())],
+        }
+    }
+
+    pub fn set_sk(&mut self, module: &Module, sk: &SecretKey) {
+        sk.prepare(module, &mut self.sk);
+        self.initialized = true;
+    }
+
+    pub fn seed_source_xa(&mut self, seed: [u8; 32]) {
+        self.source_xa = Source::new(seed)
+    }
+
+    pub fn seed_source_xe(&mut self, seed: [u8; 32]) {
+        self.source_xe = Source::new(seed)
     }
 
     pub fn encrypt_rlwe_sk(
+        &mut self,
+        params: &Parameters,
+        ct: &mut Ciphertext,
+        pt: Option<&Plaintext>,
+    ) {
+        assert!(
+            self.initialized == true,
+            "invalid call to [EncryptorSk.encrypt_rlwe_sk]: [EncryptorSk] has not been initialized with a [SecretKey]"
+        );
+        params.encrypt_rlwe_sk_thread_safe(
+            ct,
+            pt,
+            &self.sk,
+            &mut self.source_xa,
+            &mut self.source_xe,
+            &mut self.tmp_bytes,
+        );
+    }
+
+    pub fn encrypt_rlwe_sk_thread_safe(
         &self,
         params: &Parameters,
         ct: &mut Ciphertext,
         pt: Option<&Plaintext>,
-        xa_source: &mut Source,
-        xe_source: &mut Source,
+        source_xa: &mut Source,
+        source_xe: &mut Source,
         tmp_bytes: &mut [u8],
     ) {
-        params.encrypt_rlwe_sk(ct, pt, &self.sk, xa_source, xe_source, tmp_bytes);
+        assert!(
+            self.initialized == true,
+            "invalid call to [EncryptorSk.encrypt_rlwe_sk_thread_safe]: [EncryptorSk] has not been initialized with a [SecretKey]"
+        );
+        params.encrypt_rlwe_sk_thread_safe(ct, pt, &self.sk, source_xa, source_xe, tmp_bytes);
     }
 }
 
 impl Parameters {
-    pub fn encrypt_rlwe_sk_tmp_bytes(&self, limbs: usize) -> usize {
-        encrypt_rlwe_sk_tmp_bytes(self.module(), limbs)
+    pub fn encrypt_rlwe_sk_tmp_bytes(&self, log_q: usize) -> usize {
+        encrypt_rlwe_sk_tmp_bytes(self.module(), self.log_base2k(), log_q)
     }
 
-    pub fn encrypt_rlwe_sk(
+    pub fn encrypt_rlwe_sk_thread_safe(
         &self,
         ct: &mut Ciphertext,
         pt: Option<&Plaintext>,
         sk: &SvpPPol,
-        xa_source: &mut Source,
-        xe_source: &mut Source,
+        source_xa: &mut Source,
+        source_xe: &mut Source,
         tmp_bytes: &mut [u8],
     ) {
-        encrypt_rlwe_sk(
+        encrypt_rlwe_sk_thread_safe(
             self.module(),
             &mut ct.0,
             pt.map(|pt| &pt.0),
             sk,
-            xa_source,
-            xe_source,
+            source_xa,
+            source_xe,
             self.xe(),
             tmp_bytes,
         )
     }
 }
 
-pub fn encrypt_rlwe_sk_tmp_bytes(module: &Module, limbs: usize) -> usize {
-    module.bytes_of_vec_znx_dft(limbs) + module.vec_znx_big_normalize_tmp_bytes()
+pub fn encrypt_rlwe_sk_tmp_bytes(module: &Module, log_base2k: usize, log_q: usize) -> usize {
+    module.bytes_of_vec_znx_dft((log_q + log_base2k - 1) / log_base2k)
+        + module.vec_znx_big_normalize_tmp_bytes()
 }
 
-pub fn encrypt_rlwe_sk(
+pub fn encrypt_rlwe_sk_thread_safe(
     module: &Module,
     ct: &mut Elem,
     pt: Option<&Elem>,
     sk: &SvpPPol,
-    xa_source: &mut Source,
-    xe_source: &mut Source,
+    source_xa: &mut Source,
+    source_xe: &mut Source,
     sigma: f64,
     tmp_bytes: &mut [u8],
 ) {
     let limbs: usize = ct.limbs();
+    let log_base2k: usize = ct.log_base2k();
+    let log_q: usize = ct.log_q();
 
     assert!(
-        tmp_bytes.len() >= encrypt_rlwe_sk_tmp_bytes(module, limbs),
+        tmp_bytes.len() >= encrypt_rlwe_sk_tmp_bytes(module, log_base2k, log_q),
         "invalid tmp_bytes: tmp_bytes={} < encrypt_rlwe_sk_tmp_bytes={}",
         tmp_bytes.len(),
-        encrypt_rlwe_sk_tmp_bytes(module, limbs)
+        encrypt_rlwe_sk_tmp_bytes(module, log_base2k, log_q)
     );
 
     let log_q: usize = ct.log_q();
@@ -86,7 +143,7 @@ pub fn encrypt_rlwe_sk(
     let c1: &mut VecZnx = ct.at_mut(1);
 
     // c1 <- Z_{2^prec}[X]/(X^{N}+1)
-    c1.fill_uniform(limbs, log_base2k, xa_source);
+    c1.fill_uniform(log_base2k, limbs, source_xa);
 
     let bytes_of_vec_znx_dft = module.bytes_of_vec_znx_dft(limbs);
 
@@ -95,7 +152,7 @@ pub fn encrypt_rlwe_sk(
         VecZnxDft::from_bytes(limbs, &mut tmp_bytes[..bytes_of_vec_znx_dft]);
 
     // Applies buf_dft <- s * c1
-    module.svp_apply_dft(&mut buf_dft, sk, c1);
+    module.svp_apply_dft(&mut buf_dft, sk, c1, limbs);
 
     // Alias scratch space
     let mut buf_big: VecZnxBig = buf_dft.as_vec_znx_big();
@@ -110,5 +167,90 @@ pub fn encrypt_rlwe_sk(
     // c0 <- normalize(buf_big) + e
     let c0: &mut VecZnx = ct.at_mut(0);
     module.vec_znx_big_normalize(log_base2k, c0, &buf_big, carry);
-    c0.add_normal(log_base2k, log_q, xe_source, sigma, (sigma * 6.0).ceil());
+    c0.add_normal(log_base2k, log_q, source_xe, sigma, (sigma * 6.0).ceil());
+}
+
+pub fn encrypt_grlwe_sk_tmp_bytes(
+    module: &Module,
+    log_base2k: usize,
+    rows: usize,
+    log_q: usize,
+) -> usize {
+    let cols = (log_q + log_base2k - 1) / log_base2k;
+    Elem::bytes_of(module, log_base2k, log_q, 1)
+        + Plaintext::bytes_of(module, log_base2k, log_q)
+        + encrypt_rlwe_sk_tmp_bytes(module, log_base2k, log_q)
+        + module.vmp_prepare_tmp_bytes(rows, cols)
+}
+
+pub fn encrypt_grlwe_sk_thread_safe(
+    module: &Module,
+    ct: &mut GadgetCiphertext,
+    m: &Scalar,
+    sk: &SvpPPol,
+    source_xa: &mut Source,
+    source_xe: &mut Source,
+    sigma: f64,
+    tmp_bytes: &mut [u8],
+) {
+    let rows: usize = ct.rows();
+    let log_q: usize = ct.log_q();
+    let log_base2k: usize = ct.log_base2k();
+
+    let min_tmp_bytes_len = encrypt_grlwe_sk_tmp_bytes(module, log_base2k, rows, log_q);
+
+    assert!(
+        tmp_bytes.len() >= min_tmp_bytes_len,
+        "invalid tmp_bytes: tmp_bytes.len()={} < encrypt_grlwe_sk_tmp_bytes={}",
+        tmp_bytes.len(),
+        min_tmp_bytes_len
+    );
+
+    let mut ptr: usize = 0;
+    let mut tmp_elem: Elem = Elem::from_bytes(module, log_base2k, ct.log_q(), 1, tmp_bytes);
+    let bytes_of_elem: usize = Elem::bytes_of(module, log_base2k, log_q, 1);
+    ptr += bytes_of_elem;
+
+    let mut tmp_pt: Plaintext =
+        Plaintext::from_bytes(module, log_base2k, log_q, &mut tmp_bytes[ptr..]);
+    ptr += Plaintext::bytes_of(module, log_base2k, log_q);
+
+    let (tmp_bytes_encrypt_sk, tmp_bytes_vmp_prepare_row) =
+        tmp_bytes[ptr..].split_at_mut(encrypt_rlwe_sk_tmp_bytes(module, log_base2k, log_q));
+
+    (0..rows).for_each(|row_i| {
+        // Sets the i-th row of the RLWE sample to m (i.e. m * 2^{-log_base2k*i})
+        tmp_pt.0.value[0].at_mut(row_i).copy_from_slice(&m.0);
+
+        // Encrypts RLWE(m * 2^{-log_base2k*i})
+        encrypt_rlwe_sk_thread_safe(
+            module,
+            &mut tmp_elem,
+            Some(&tmp_pt.0),
+            sk,
+            source_xa,
+            source_xe,
+            sigma,
+            tmp_bytes_encrypt_sk,
+        );
+
+        // Zeroes the ith-row of tmp_pt
+        tmp_pt.0.value[0].at_mut(row_i).fill(0);
+
+        // GRLWE[row_i][0] = -as + m * 2^{-i*log_base2k} + e*2^{-log_q}
+        module.vmp_prepare_row(
+            &mut ct.value[0],
+            tmp_elem.at(0),
+            row_i,
+            tmp_bytes_vmp_prepare_row,
+        );
+
+        // GRLWE[row_i][1] = a
+        module.vmp_prepare_row(
+            &mut ct.value[1],
+            tmp_elem.at(1),
+            row_i,
+            tmp_bytes_vmp_prepare_row,
+        );
+    })
 }

rlwe/src/evaluator.rs

@@ -0,0 +1,82 @@
+use crate::ciphertext::{Ciphertext, GadgetCiphertext};
+use base2k::{Module, VecZnxBig, VecZnxDft, VmpPMatOps};
+
+pub fn gadget_product_tmp_bytes(
+    module: &Module,
+    log_base2k: usize,
+    out_log_q: usize,
+    in_log_q: usize,
+    gct_rows: usize,
+    gct_log_q: usize,
+) -> usize {
+    let gct_cols: usize = (gct_log_q + log_base2k - 1) / log_base2k;
+    let in_limbs: usize = (in_log_q + log_base2k - 1) / log_base2k;
+    let out_limbs: usize = (out_log_q + log_base2k - 1) / log_base2k;
+    module.vmp_apply_dft_to_dft_tmp_bytes(out_limbs, in_limbs, gct_rows, gct_cols)
+        + 2 * module.bytes_of_vec_znx_dft(gct_cols)
+}
+
+pub fn gadget_product_inplace(
+    module: &Module,
+    a: &mut Ciphertext,
+    b: &GadgetCiphertext,
+    tmp_bytes: &mut [u8],
+) {
+    // This is safe to do because the relevant values of a are copied to a buffer before being
+    // overwritten.
+    unsafe {
+        let a_ptr: *mut Ciphertext = a;
+        gadget_product(module, a, &*a_ptr, b, tmp_bytes)
+    }
+}
+
+pub fn gadget_product(
+    module: &Module,
+    res: &mut Ciphertext,
+    a: &Ciphertext,
+    b: &GadgetCiphertext,
+    tmp_bytes: &mut [u8],
+) {
+    assert!(
+        a.log_base2k() == b.log_base2k(),
+        "invalid inputs: a.log_base2k={} != b.log_base2k={}",
+        a.log_base2k(),
+        b.log_base2k()
+    );
+
+    let log_base2k: usize = b.log_base2k();
+    let cols: usize = b.cols();
+
+    let (tmp_bytes_vmp_apply_dft, tmp_bytes) =
+        tmp_bytes.split_at_mut(module.bytes_of_vec_znx_dft(cols));
+
+    let (tmp_bytes_c1_dft, tmp_bytes_res_dft) = tmp_bytes.split_at_mut(tmp_bytes.len() >> 1);
+
+    let mut c1_dft: VecZnxDft = module.new_vec_znx_from_bytes(cols, tmp_bytes_c1_dft);
+    let mut res_dft: VecZnxDft = module.new_vec_znx_from_bytes(cols, tmp_bytes_res_dft);
+    let mut res_big: VecZnxBig = res_dft.as_vec_znx_big();
+
+    // c1_dft <- DFT(b[1])
+    module.vec_znx_dft(&mut c1_dft, a.at(1), a.limbs());
+
+    // res_dft <- DFT(c1) x GadgetCiphertext[0]
+    module.vmp_apply_dft_to_dft(&mut res_dft, &c1_dft, &b.value[0], tmp_bytes_vmp_apply_dft);
+
+    // res_big <- IDFT(DFT(c1) x GadgetCiphertext[0])
+    module.vec_znx_idft_tmp_a(&mut res_big, &mut res_dft, cols);
+
+    // res_big <- c0 + c1_dft x GadgetCiphertext[0]
+    module.vec_znx_big_add_small_inplace(&mut res_big, a.at(0), cols);
+
+    // res[0] = normalize(c0 + c1_dft x GadgetCiphertext[0])
+    module.vec_znx_big_normalize(log_base2k, res.at_mut(0), &res_big, tmp_bytes_vmp_apply_dft);
+
+    // res_dft <- DFT(c1) x GadgetCiphertext[1]
+    module.vmp_apply_dft_to_dft(&mut res_dft, &c1_dft, &b.value[1], tmp_bytes_vmp_apply_dft);
+
+    // res_big <- IDFT(DFT(c1) x GadgetCiphertext[1])
+    module.vec_znx_idft_tmp_a(&mut res_big, &mut res_dft, cols);
+
+    // res[1] = normalize(c1_dft x GadgetCiphertext[1])
+    module.vec_znx_big_normalize(log_base2k, res.at_mut(1), &res_big, tmp_bytes_vmp_apply_dft);
+}

rlwe/src/key_generator.rs

@@ -1 +1,53 @@
+use crate::keys::{PublicKey, SecretKey, SwitchingKey};
+use crate::parameters::Parameters;
+use base2k::SvpPPol;
+use sampling::source::Source;
+
 pub struct KeyGenerator {}
+
+impl KeyGenerator {
+    pub fn gen_secret_key_thread_safe(
+        &self,
+        params: &Parameters,
+        source: &mut Source,
+    ) -> SecretKey {
+        let mut sk: SecretKey = SecretKey::new(params.module());
+        sk.fill_ternary_hw(params.xs(), source);
+        sk
+    }
+
+    pub fn gen_public_key_thread_safe(
+        &self,
+        params: &Parameters,
+        sk_ppol: &SvpPPol,
+        source: &mut Source,
+        tmp_bytes: &mut [u8],
+    ) -> PublicKey {
+        let mut xa_source: Source = source.branch();
+        let mut xe_source: Source = source.branch();
+        let mut pk: PublicKey =
+            PublicKey::new(params.module(), params.log_base2k(), params.log_qp());
+        pk.gen_thread_safe(
+            params.module(),
+            sk_ppol,
+            params.xe(),
+            &mut xa_source,
+            &mut xe_source,
+            tmp_bytes,
+        );
+        pk
+    }
+
+    pub fn gen_switching_key(
+        &self,
+        params: &Parameters,
+        sk_in: &SecretKey,
+        sk_out: &SecretKey,
+        rows: usize,
+        log_q: usize,
+    ) -> SwitchingKey {
+        let swk = SwitchingKey::new(params.module(), params.log_base2k(), rows, log_q, 0);
+
+        swk
+    }
+}

rlwe/src/keys.rs

@@ -1,44 +1,86 @@
+use crate::ciphertext::GadgetCiphertext;
 use crate::elem::Elem;
-use crate::encryptor::{encrypt_rlwe_sk, encrypt_rlwe_sk_tmp_bytes};
+use crate::encryptor::{encrypt_rlwe_sk_thread_safe, encrypt_rlwe_sk_tmp_bytes};
 use crate::parameters::Parameters;
-use base2k::{Module, Sampling, Scalar, SvpPPol, SvpPPolOps, VecZnx};
+use base2k::{Module, Scalar, SvpPPol, SvpPPolOps, VmpPMat, VmpPMatOps};
 use sampling::source::Source;
 
 pub struct SecretKey(pub Scalar);
 
 impl SecretKey {
-    pub fn new_ternary_prob(module: &Module, limbs: usize, prob: f64, source: &mut Source) -> Self {
-        let mut sk: Scalar = Scalar::new(module.n());
-        sk.fill_ternary_prob(prob, source);
-        SecretKey(sk)
+    pub fn new(params: &Module) -> Self {
+        SecretKey(Scalar::new(params.n()))
+    }
+
+    pub fn fill_ternary_prob(&mut self, prob: f64, source: &mut Source) {
+        self.0.fill_ternary_prob(prob, source);
+    }
+
+    pub fn fill_ternary_hw(&mut self, hw: usize, source: &mut Source) {
+        self.0.fill_ternary_hw(hw, source);
+    }
+
+    pub fn prepare(&self, module: &Module, sk_ppol: &mut SvpPPol) {
+        module.svp_prepare(sk_ppol, &self.0)
     }
 }
 
 pub struct PublicKey(pub Elem);
 
 impl PublicKey {
-    pub fn new(
-        params: &Parameters,
+    pub fn new(module: &Module, log_base2k: usize, log_q: usize) -> PublicKey {
+        PublicKey(Elem::new(module, log_base2k, log_q, 1, 0))
+    }
+
+    pub fn gen_thread_safe(
+        &mut self,
+        module: &Module,
         sk: &SvpPPol,
+        xe: f64,
         xa_source: &mut Source,
         xe_source: &mut Source,
         tmp_bytes: &mut [u8],
-    ) -> Self {
-        let mut pk: Elem = Elem::new(params.n(), params.log_base2k(), params.log_qp(), 1);
-        encrypt_rlwe_sk(
-            params.module(),
-            &mut pk,
+    ) {
+        encrypt_rlwe_sk_thread_safe(
+            module,
+            &mut self.0,
             None,
             sk,
             xa_source,
             xe_source,
-            params.xe(),
+            xe,
             tmp_bytes,
         );
-        PublicKey(pk)
     }
 
-    pub fn new_tmp_bytes(params: &Parameters) -> usize {
-        encrypt_rlwe_sk_tmp_bytes(params.module(), params.limbs_qp())
+    pub fn gen_thread_safe_tmp_bytes(module: &Module, log_base2k: usize, log_q: usize) -> usize {
+        encrypt_rlwe_sk_tmp_bytes(module, log_base2k, log_q)
+    }
+}
+
+pub struct SwitchingKey(GadgetCiphertext);
+
+impl SwitchingKey {
+    pub fn new(
+        module: &Module,
+        log_base2k: usize,
+        rows: usize,
+        log_q: usize,
+        log_scale: usize,
+    ) -> SwitchingKey {
+        SwitchingKey(GadgetCiphertext::new(
+            module, log_base2k, rows, log_q, log_scale,
+        ))
+    }
+
+    pub fn gen_thread_safe(
+        &mut self,
+        params: &mut Parameters,
+        sk_in: &SvpPPol,
+        sk_out: &SvpPPol,
+        xa_source: &mut Source,
+        xe_source: &mut Source,
+        tmp_bytes: &mut [u8],
+    ) {
     }
 }

rlwe/src/lib.rs

@@ -1,6 +1,8 @@
 pub mod ciphertext;
+pub mod decryptor;
 pub mod elem;
 pub mod encryptor;
+pub mod evaluator;
 pub mod key_generator;
 pub mod keys;
 pub mod parameters;

rlwe/src/plaintext.rs

@@ -1,20 +1,35 @@
 use crate::ciphertext::Ciphertext;
 use crate::elem::Elem;
-use base2k::VecZnx;
+use crate::parameters::Parameters;
+use base2k::{Module, VecZnx};
 
 pub struct Plaintext(pub Elem);
 
-/*
 impl Parameters {
     pub fn new_plaintext(&self, log_q: usize) -> Plaintext {
-        Plaintext(self.new_elem(0, log_q))
+        Plaintext::new(self.module(), self.log_base2k(), log_q, self.log_scale())
+    }
+
+    pub fn bytes_of_plaintext(&self, log_q: usize) -> usize {
+        Elem::bytes_of(self.module(), self.log_base2k(), log_q, 0)
+    }
+
+    pub fn plaintext_from_bytes(&self, log_q: usize, bytes: &mut [u8]) -> Plaintext {
+        Plaintext(self.elem_from_bytes(log_q, 0, bytes))
     }
 }
-*/
 
 impl Plaintext {
-    pub fn new(n: usize, log_base2k: usize, log_q: usize) -> Self {
-        Self(Elem::new(n, log_base2k, log_q, 0))
+    pub fn new(module: &Module, log_base2k: usize, log_q: usize, log_scale: usize) -> Self {
+        Self(Elem::new(module, log_base2k, log_q, 0, log_scale))
+    }
+
+    pub fn bytes_of(module: &Module, log_base2k: usize, log_q: usize) -> usize {
+        Elem::bytes_of(module, log_base2k, log_q, 0)
+    }
+
+    pub fn from_bytes(module: &Module, log_base2k: usize, log_q: usize, bytes: &mut [u8]) -> Self {
+        Self(Elem::from_bytes(module, log_base2k, log_q, 0, bytes))
     }
 
     pub fn n(&self) -> usize {
@@ -45,6 +60,10 @@ impl Plaintext {
         self.0.log_base2k()
     }
 
+    pub fn log_scale(&self) -> usize {
+        self.0.log_scale()
+    }
+
     pub fn as_ciphertext(&self) -> Ciphertext {
         unsafe { Ciphertext(std::ptr::read(&self.0)) }
     }