Added tensor key & associated test

base2k/src/scalar_znx.rs

@@ -9,9 +9,9 @@ use rand_distr::{Distribution, weighted::WeightedIndex};
 use sampling::source::Source;
 
 pub struct ScalarZnx<D> {
-    data: D,
+    pub(crate) data: D,
-    n: usize,
+    pub(crate) n: usize,
-    cols: usize,
+    pub(crate) cols: usize,
 }
 
 impl<D> ZnxInfos for ScalarZnx<D> {

base2k/src/scalar_znx_dft.rs

@@ -2,7 +2,7 @@ use std::marker::PhantomData;
 
 use crate::ffi::svp;
 use crate::znx_base::ZnxInfos;
-use crate::{Backend, DataView, DataViewMut, FFT64, Module, ZnxSliceSize, ZnxView, alloc_aligned};
+use crate::{alloc_aligned, Backend, DataView, DataViewMut, Module, VecZnxDft, VecZnxDftToMut, VecZnxDftToRef, ZnxSliceSize, ZnxView, FFT64};
 
 pub struct ScalarZnxDft<D, B: Backend> {
     data: D,
@@ -92,6 +92,16 @@ impl<D, B: Backend> ScalarZnxDft<D, B> {
             _phantom: PhantomData,
         }
     }
+
+    pub fn as_vec_znx_dft(self) -> VecZnxDft<D, B>{
+        VecZnxDft{
+            data: self.data,
+            n: self.n,
+            cols: self.cols,
+            size: 1,
+            _phantom: PhantomData,
+        }
+    }
 }
 
 pub type ScalarZnxDftOwned<B> = ScalarZnxDft<Vec<u8>, B>;
@@ -158,3 +168,63 @@ impl<B: Backend> ScalarZnxDftToRef<B> for ScalarZnxDft<&[u8], B> {
         }
     }
 }
+
+impl<B: Backend> VecZnxDftToMut<B> for ScalarZnxDft<Vec<u8>, B> {
+    fn to_mut(&mut self) -> VecZnxDft<&mut [u8], B> {
+        VecZnxDft {
+            data: self.data.as_mut_slice(),
+            n: self.n,
+            cols: self.cols,
+            size: 1,
+            _phantom: PhantomData,
+        }
+    }
+}
+
+impl<B: Backend> VecZnxDftToRef<B> for ScalarZnxDft<Vec<u8>, B> {
+    fn to_ref(&self) -> VecZnxDft<&[u8], B> {
+        VecZnxDft {
+            data: self.data.as_slice(),
+            n: self.n,
+            cols: self.cols,
+            size: 1,
+            _phantom: PhantomData,
+        }
+    }
+}
+
+impl<B: Backend> VecZnxDftToMut<B> for ScalarZnxDft<&mut [u8], B> {
+    fn to_mut(&mut self) -> VecZnxDft<&mut [u8], B> {
+        VecZnxDft {
+            data: self.data,
+            n: self.n,
+            cols: self.cols,
+            size: 1,
+            _phantom: PhantomData,
+        }
+    }
+}
+
+impl<B: Backend> VecZnxDftToRef<B> for ScalarZnxDft<&mut [u8], B> {
+    fn to_ref(&self) -> VecZnxDft<&[u8], B> {
+        VecZnxDft {
+            data: self.data,
+            n: self.n,
+            cols: self.cols,
+            size: 1,
+            _phantom: PhantomData,
+        }
+    }
+}
+
+impl<B: Backend> VecZnxDftToRef<B> for ScalarZnxDft<&[u8], B> {
+    fn to_ref(&self) -> VecZnxDft<&[u8], B> {
+        VecZnxDft {
+            data: self.data,
+            n: self.n,
+            cols: self.cols,
+            size: 1,
+            _phantom: PhantomData,
+        }
+    }
+}

base2k/src/vec_znx.rs

@@ -1,5 +1,6 @@
 use crate::DataView;
 use crate::DataViewMut;
+use crate::ScalarZnx;
 use crate::ZnxSliceSize;
 use crate::ZnxZero;
 use crate::alloc_aligned;
@@ -128,6 +129,15 @@ impl<D> VecZnx<D> {
             size,
         }
     }
+
+    pub fn to_scalar_znx(self) -> ScalarZnx<D>{
+        debug_assert_eq!(self.size, 1, "cannot convert VecZnx to ScalarZnx if cols: {} != 1", self.cols);
+        ScalarZnx{
+            data: self.data,
+            n: self.n,
+            cols: self.cols,
+        }
+    }
 }
 
 /// Copies the coefficients of `a` on the receiver.

base2k/src/vec_znx_dft.rs

@@ -8,11 +8,11 @@ use crate::{
 use std::fmt;
 
 pub struct VecZnxDft<D, B: Backend> {
-    data: D,
+    pub(crate) data: D,
-    n: usize,
+    pub(crate) n: usize,
-    cols: usize,
+    pub(crate) cols: usize,
-    size: usize,
+    pub(crate) size: usize,
-    _phantom: PhantomData<B>,
+    pub(crate) _phantom: PhantomData<B>,
 }
 
 impl<D, B: Backend> VecZnxDft<D, B> {

core/src/ggsw_ciphertext.rs

@@ -6,6 +6,7 @@ use base2k::{
 use sampling::source::Source;
 
 use crate::{
+    automorphism::AutomorphismKey,
     elem::{GetRow, Infos, SetRow},
     glwe_ciphertext::GLWECiphertext,
     glwe_ciphertext_fourier::GLWECiphertextFourier,
@@ -78,6 +79,20 @@ impl GGSWCiphertext<Vec<u8>, FFT64> {
             + module.bytes_of_vec_znx_dft(rank + 1, size)
     }
 
+    pub fn automorphism_scratch_space(
+        module: &Module<FFT64>,
+        out_size: usize,
+        in_size: usize,
+        auto_key_size: usize,
+        rank: usize,
+    ) -> usize {
+        let size: usize = in_size.min(out_size);
+        let tmp_dft: usize = module.bytes_of_vec_znx_dft(rank + 1, size);
+        let tmp_idft: usize = module.bytes_of_vec_znx(rank + 1, size);
+        let vmp: usize = GLWECiphertext::keyswitch_from_fourier_scratch_space(module, size, rank, size, rank, auto_key_size);
+        tmp_dft + tmp_idft + vmp
+    }
+
     pub fn external_product_scratch_space(
         module: &Module<FFT64>,
         out_size: usize,
@@ -182,6 +197,73 @@ where
         });
     }
 
+    pub fn automorphism<DataLhs, DataRhs>(
+        &mut self,
+        module: &Module<FFT64>,
+        lhs: &GGSWCiphertext<DataLhs, FFT64>,
+        rhs: &AutomorphismKey<DataRhs, FFT64>,
+        scratch: &mut Scratch,
+    ) where
+        MatZnxDft<DataLhs, FFT64>: MatZnxDftToRef<FFT64>,
+        MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
+    {
+        #[cfg(debug_assertions)]
+        {
+            assert_eq!(
+                self.rank(),
+                lhs.rank(),
+                "ggsw_out rank: {} != ggsw_in rank: {}",
+                self.rank(),
+                lhs.rank()
+            );
+            assert_eq!(
+                self.rank(),
+                rhs.rank(),
+                "ggsw_in rank: {} != auto_key rank: {}",
+                self.rank(),
+                rhs.rank()
+            );
+        }
+
+        let size: usize = self.size().min(lhs.size());
+        let cols: usize = self.rank() + 1;
+
+        let (tmp_dft_data, scratch1) = scratch.tmp_vec_znx_dft(module, cols, size);
+
+        let mut tmp_dft: GLWECiphertextFourier<&mut [u8], FFT64> = GLWECiphertextFourier::<&mut [u8], FFT64> {
+            data: tmp_dft_data,
+            basek: lhs.basek(),
+            k: lhs.k(),
+        };
+
+        let (tmp_idft_data, scratch2) = scratch1.tmp_vec_znx(module, cols, size);
+
+        let mut tmp_idft: GLWECiphertext<&mut [u8]> = GLWECiphertext::<&mut [u8]> {
+            data: tmp_idft_data,
+            basek: self.basek(),
+            k: self.k(),
+        };
+
+        (0..cols).for_each(|col_i| {
+            (0..self.rows()).for_each(|row_j| {
+                lhs.get_row(module, row_j, col_i, &mut tmp_dft);
+                tmp_idft.keyswitch_from_fourier(module, &tmp_dft, &rhs.key, scratch2);
+                (0..cols).for_each(|i| {
+                    module.vec_znx_automorphism_inplace(rhs.p(), &mut tmp_idft, i);
+                });
+                self.set_row(module, row_j, col_i, &tmp_dft);
+            });
+        });
+
+        tmp_dft.data.zero();
+
+        (self.rows().min(lhs.rows())..self.rows()).for_each(|row_i| {
+            (0..self.rank() + 1).for_each(|col_j| {
+                self.set_row(module, row_i, col_j, &tmp_dft);
+            });
+        });
+    }
+
     pub fn external_product<DataLhs, DataRhs>(
         &mut self,
         module: &Module<FFT64>,

core/src/lib.rs

@@ -7,6 +7,7 @@ pub mod glwe_ciphertext_fourier;
 pub mod glwe_plaintext;
 pub mod keys;
 pub mod keyswitch_key;
+pub mod tensor_key;
 #[cfg(test)]
 mod test_fft64;
 mod utils;

core/src/tensor_key.rs

@@ -0,0 +1,125 @@
+use base2k::{
+    Backend, FFT64, MatZnxDft, MatZnxDftToMut, MatZnxDftToRef, Module, ScalarZnx, ScalarZnxDft, ScalarZnxDftAlloc,
+    ScalarZnxDftOps, ScalarZnxDftToRef, Scratch, VecZnxDftOps, VecZnxDftToRef,
+};
+use sampling::source::Source;
+
+use crate::{
+    elem::Infos,
+    keys::{SecretKey, SecretKeyFourier},
+    keyswitch_key::GLWESwitchingKey,
+};
+
+pub struct TensorKey<C, B: Backend> {
+    pub(crate) keys: Vec<GLWESwitchingKey<C, B>>,
+}
+
+impl TensorKey<Vec<u8>, FFT64> {
+    pub fn new(module: &Module<FFT64>, basek: usize, k: usize, rows: usize, rank: usize) -> Self {
+        let mut keys: Vec<GLWESwitchingKey<Vec<u8>, FFT64>> = Vec::new();
+        let pairs: usize = ((rank + 1) * rank) >> 1;
+        (0..pairs).for_each(|_| {
+            keys.push(GLWESwitchingKey::new(module, basek, k, rows, 1, rank));
+        });
+        Self { keys: keys }
+    }
+}
+
+impl<T, B: Backend> Infos for TensorKey<T, B> {
+    type Inner = MatZnxDft<T, B>;
+
+    fn inner(&self) -> &Self::Inner {
+        &self.keys[0].inner()
+    }
+
+    fn basek(&self) -> usize {
+        self.keys[0].basek()
+    }
+
+    fn k(&self) -> usize {
+        self.keys[0].k()
+    }
+}
+
+impl<T, B: Backend> TensorKey<T, B> {
+    pub fn rank(&self) -> usize {
+        self.keys[0].rank()
+    }
+
+    pub fn rank_in(&self) -> usize {
+        self.keys[0].rank_in()
+    }
+
+    pub fn rank_out(&self) -> usize {
+        self.keys[0].rank_out()
+    }
+}
+
+impl TensorKey<Vec<u8>, FFT64> {
+    pub fn encrypt_sk_scratch_space(module: &Module<FFT64>, rank: usize, size: usize) -> usize {
+        module.bytes_of_scalar_znx_dft(1) + GLWESwitchingKey::encrypt_sk_scratch_space(module, rank, size)
+    }
+}
+
+impl<DataSelf> TensorKey<DataSelf, FFT64>
+where
+    MatZnxDft<DataSelf, FFT64>: MatZnxDftToMut<FFT64> + MatZnxDftToRef<FFT64>,
+{
+    pub fn encrypt_sk<DataSk>(
+        &mut self,
+        module: &Module<FFT64>,
+        sk_dft: &SecretKeyFourier<DataSk, FFT64>,
+        source_xa: &mut Source,
+        source_xe: &mut Source,
+        sigma: f64,
+        scratch: &mut Scratch,
+    ) where
+        ScalarZnxDft<DataSk, FFT64>: VecZnxDftToRef<FFT64> + ScalarZnxDftToRef<FFT64>,
+    {
+        #[cfg(debug_assertions)]
+        {
+            assert_eq!(self.rank(), sk_dft.rank());
+            assert_eq!(self.n(), module.n());
+            assert_eq!(sk_dft.n(), module.n());
+        }
+
+        let rank: usize = self.rank();
+
+        (0..rank).for_each(|i| {
+            (i..rank).for_each(|j| {
+                let (mut sk_ij_dft, scratch1) = scratch.tmp_scalar_znx_dft(module, 1);
+                module.svp_apply(&mut sk_ij_dft, 0, &sk_dft.data, i, &sk_dft.data, j);
+                let sk_ij: ScalarZnx<&mut [u8]> = module
+                    .vec_znx_idft_consume(sk_ij_dft.as_vec_znx_dft())
+                    .to_vec_znx_small()
+                    .to_scalar_znx();
+                let sk_ij: SecretKey<&mut [u8]> = SecretKey {
+                    data: sk_ij,
+                    dist: sk_dft.dist,
+                };
+
+                self.at_mut(i, j).encrypt_sk(
+                    module, &sk_ij, sk_dft, source_xa, source_xe, sigma, scratch1,
+                );
+            });
+        })
+    }
+
+    // Returns a reference to GLWESwitchingKey_{s}(s[i] * s[j])
+    pub fn at(&self, mut i: usize, mut j: usize) -> &GLWESwitchingKey<DataSelf, FFT64> {
+        if i > j {
+            std::mem::swap(&mut i, &mut j);
+        };
+        let rank: usize = self.rank();
+        &self.keys[i * rank + j - (i * (i + 1) / 2)]
+    }
+
+    // Returns a mutable reference to GLWESwitchingKey_{s}(s[i] * s[j])
+    pub fn at_mut(&mut self, mut i: usize, mut j: usize) -> &mut GLWESwitchingKey<DataSelf, FFT64> {
+        if i > j {
+            std::mem::swap(&mut i, &mut j);
+        };
+        let rank: usize = self.rank();
+        &mut self.keys[i * rank + j - (i * (i + 1) / 2)]
+    }
+}

core/src/test_fft64/automorphism_key.rs

@@ -18,6 +18,14 @@ fn automorphism() {
     });
 }
 
+#[test]
+fn automorphism_inplace() {
+    (1..4).for_each(|rank| {
+        println!("test automorphism_inplace rank: {}", rank);
+        test_automorphism_inplace(-1, 5, 12, 12, 60, 3.2, rank);
+    });
+}
+
 fn test_automorphism(p0: i64, p1: i64, log_n: usize, basek: usize, k_ksk: usize, sigma: f64, rank: usize) {
     let module: Module<FFT64> = Module::<FFT64>::new(1 << log_n);
     let rows = (k_ksk + basek - 1) / basek;
@@ -115,3 +123,94 @@ fn test_automorphism(p0: i64, p1: i64, log_n: usize, basek: usize, k_ksk: usize,
         });
     });
 }
+
+fn test_automorphism_inplace(p0: i64, p1: i64, log_n: usize, basek: usize, k_ksk: usize, sigma: f64, rank: usize) {
+    let module: Module<FFT64> = Module::<FFT64>::new(1 << log_n);
+    let rows = (k_ksk + basek - 1) / basek;
+
+    let mut auto_key: AutomorphismKey<Vec<u8>, FFT64> = AutomorphismKey::new(&module, basek, k_ksk, rows, rank);
+    let mut auto_key_apply: AutomorphismKey<Vec<u8>, FFT64> = AutomorphismKey::new(&module, basek, k_ksk, rows, rank);
+
+    let mut source_xs: Source = Source::new([0u8; 32]);
+    let mut source_xe: Source = Source::new([0u8; 32]);
+    let mut source_xa: Source = Source::new([0u8; 32]);
+
+    let mut scratch: ScratchOwned = ScratchOwned::new(
+        AutomorphismKey::encrypt_sk_scratch_space(&module, rank, auto_key.size())
+            | GLWECiphertextFourier::decrypt_scratch_space(&module, auto_key.size())
+            | AutomorphismKey::automorphism_inplace_scratch_space(&module, auto_key.size(), auto_key_apply.size(), rank),
+    );
+
+    let mut sk: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
+    sk.fill_ternary_prob(0.5, &mut source_xs);
+
+    let mut sk_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
+    sk_dft.dft(&module, &sk);
+
+    // gglwe_{s1}(s0) = s0 -> s1
+    auto_key.encrypt_sk(
+        &module,
+        p0,
+        &sk,
+        &mut source_xa,
+        &mut source_xe,
+        sigma,
+        scratch.borrow(),
+    );
+
+    // gglwe_{s2}(s1) -> s1 -> s2
+    auto_key_apply.encrypt_sk(
+        &module,
+        p1,
+        &sk,
+        &mut source_xa,
+        &mut source_xe,
+        sigma,
+        scratch.borrow(),
+    );
+
+    // gglwe_{s1}(s0) (x) gglwe_{s2}(s1) = gglwe_{s2}(s0)
+    auto_key.automorphism_inplace(&module, &auto_key_apply, scratch.borrow());
+
+    let mut ct_glwe_dft: GLWECiphertextFourier<Vec<u8>, FFT64> = GLWECiphertextFourier::new(&module, basek, k_ksk, rank);
+    let mut pt: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, basek, k_ksk);
+
+    let mut sk_auto: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
+    sk_auto.fill_zero(); // Necessary to avoid panic of unfilled sk
+    (0..rank).for_each(|i| {
+        module.scalar_znx_automorphism(module.galois_element_inv(p0 * p1), &mut sk_auto, i, &sk, i);
+    });
+
+    let mut sk_auto_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
+    sk_auto_dft.dft(&module, &sk_auto);
+
+    (0..auto_key.rank_in()).for_each(|col_i| {
+        (0..auto_key.rows()).for_each(|row_i| {
+            auto_key.get_row(&module, row_i, col_i, &mut ct_glwe_dft);
+
+            ct_glwe_dft.decrypt(&module, &mut pt, &sk_auto_dft, scratch.borrow());
+            module.vec_znx_sub_scalar_inplace(&mut pt, 0, row_i, &sk, col_i);
+
+            let noise_have: f64 = pt.data.std(0, basek).log2();
+            let noise_want: f64 = noise_gglwe_product(
+                module.n() as f64,
+                basek,
+                0.5,
+                0.5,
+                0f64,
+                sigma * sigma,
+                0f64,
+                rank as f64,
+                k_ksk,
+                k_ksk,
+            );
+
+            assert!(
+                (noise_have - noise_want).abs() <= 0.1,
+                "{} {}",
+                noise_have,
+                noise_want
+            );
+        });
+    });
+}

core/src/test_fft64/ggsw.rs

@@ -5,6 +5,7 @@ use base2k::{
 use sampling::source::Source;
 
 use crate::{
+    automorphism::AutomorphismKey,
     elem::{GetRow, Infos},
     ggsw_ciphertext::GGSWCiphertext,
     glwe_ciphertext_fourier::GLWECiphertextFourier,
@@ -104,6 +105,123 @@ fn test_encrypt_sk(log_n: usize, basek: usize, k_ggsw: usize, sigma: f64, rank:
     });
 }
 
+// fn test_automorphism(p: i64, log_n: usize, basek: usize, k: usize, rank: usize, sigma: f64) {
+// let module: Module<FFT64> = Module::<FFT64>::new(1 << log_n);
+// let rows: usize = (k_ggsw + basek - 1) / basek;
+//
+// let mut ct_ggsw_in: GGSWCiphertext<Vec<u8>, FFT64> = GGSWCiphertext::new(&module, basek, k, rows, rank);
+// let mut ct_ggsw_out: GGSWCiphertext<Vec<u8>, FFT64> = GGSWCiphertext::new(&module, basek, k, rows, rank);
+// let mut auto_key: AutomorphismKey<Vec<u8>, FFT64> = AutomorphismKey::new(&module, basek, k, rows, rank);
+//
+// let mut pt_ggsw_in: ScalarZnx<Vec<u8>> = module.new_scalar_znx(1);
+// let mut pt_ggsw_out: ScalarZnx<Vec<u8>> = module.new_scalar_znx(1);
+//
+// let mut source_xs: Source = Source::new([0u8; 32]);
+// let mut source_xe: Source = Source::new([0u8; 32]);
+// let mut source_xa: Source = Source::new([0u8; 32]);
+//
+// pt_ggsw_in.fill_ternary_prob(0, 0.5, &mut source_xs);
+//
+// let mut scratch: ScratchOwned = ScratchOwned::new(
+// AutomorphismKey::encrypt_sk_scratch_space(&module, rank, auto_key.size())
+// | GLWECiphertextFourier::decrypt_scratch_space(&module, ct_ggsw_out.size())
+// | GGSWCiphertext::encrypt_sk_scratch_space(&module, rank, ct_ggsw_in.size())
+// | GGSWCiphertext::automorphism_scratch_space(
+// &module,
+// ct_ggsw_out.size(),
+// ct_ggsw_in.size(),
+// auto_key.size(),
+// rank,
+// ),
+// );
+//
+// let mut sk: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
+// sk.fill_ternary_prob(0.5, &mut source_xs);
+//
+// let mut sk_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
+// sk_dft.dft(&module, &sk);
+//
+// ct_ggsw_in.encrypt_sk(
+// &module,
+// &pt_ggsw_in,
+// &sk_dft,
+// &mut source_xa,
+// &mut source_xe,
+// sigma,
+// scratch.borrow(),
+// );
+//
+// auto_key.encrypt_sk(
+// &module,
+// p,
+// &sk,
+// &mut source_xa,
+// &mut source_xe,
+// sigma,
+// scratch.borrow(),
+// );
+//
+// ct_ggsw_out.automorphism(&module, &ct_ggsw_in, &auto_key, scratch.borrow());
+//
+// let mut ct_glwe_fourier: GLWECiphertextFourier<Vec<u8>, FFT64> = GLWECiphertextFourier::new(&module, basek, k_ggsw, rank);
+// let mut pt: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, basek, k_ggsw);
+// let mut pt_dft: VecZnxDft<Vec<u8>, FFT64> = module.new_vec_znx_dft(1, ct_ggsw_lhs_out.size());
+// let mut pt_big: VecZnxBig<Vec<u8>, FFT64> = module.new_vec_znx_big(1, ct_ggsw_lhs_out.size());
+// let mut pt_want: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, basek, k_ggsw);
+//
+// module.vec_znx_rotate_inplace(k as i64, &mut pt_ggsw_lhs, 0);
+//
+// (0..ct_ggsw_lhs_out.rank() + 1).for_each(|col_j| {
+// (0..ct_ggsw_lhs_out.rows()).for_each(|row_i| {
+// module.vec_znx_add_scalar_inplace(&mut pt_want, 0, row_i, &pt_ggsw_lhs, 0);
+//
+// if col_j > 0 {
+// module.vec_znx_dft(&mut pt_dft, 0, &pt_want, 0);
+// module.svp_apply_inplace(&mut pt_dft, 0, &sk_dft, col_j - 1);
+// module.vec_znx_idft_tmp_a(&mut pt_big, 0, &mut pt_dft, 0);
+// module.vec_znx_big_normalize(basek, &mut pt_want, 0, &pt_big, 0, scratch.borrow());
+// }
+//
+// ct_ggsw_lhs_out.get_row(&module, row_i, col_j, &mut ct_glwe_fourier);
+// ct_glwe_fourier.decrypt(&module, &mut pt, &sk_dft, scratch.borrow());
+//
+// module.vec_znx_sub_ab_inplace(&mut pt, 0, &pt_want, 0);
+//
+// let noise_have: f64 = pt.data.std(0, basek).log2();
+//
+// let var_gct_err_lhs: f64 = sigma * sigma;
+// let var_gct_err_rhs: f64 = 0f64;
+//
+// let var_msg: f64 = 1f64 / module.n() as f64; // X^{k}
+// let var_a0_err: f64 = sigma * sigma;
+// let var_a1_err: f64 = 1f64 / 12f64;
+//
+// let noise_want: f64 = noise_ggsw_product(
+// module.n() as f64,
+// basek,
+// 0.5,
+// var_msg,
+// var_a0_err,
+// var_a1_err,
+// var_gct_err_lhs,
+// var_gct_err_rhs,
+// rank as f64,
+// k_ggsw,
+// k_ggsw,
+// );
+//
+// assert!(
+// (noise_have - noise_want).abs() <= 0.1,
+// "have: {} want: {}",
+// noise_have,
+// noise_want
+// );
+//
+// pt_want.data.zero();
+// });
+// });
+// }
+
 fn test_external_product(log_n: usize, basek: usize, k_ggsw: usize, rank: usize, sigma: f64) {
     let module: Module<FFT64> = Module::<FFT64>::new(1 << log_n);
 
@@ -126,8 +244,7 @@ fn test_external_product(log_n: usize, basek: usize, k_ggsw: usize, rank: usize,
     pt_ggsw_rhs.to_mut().raw_mut()[k] = 1; //X^{k}
 
     let mut scratch: ScratchOwned = ScratchOwned::new(
-        GLWESwitchingKey::encrypt_sk_scratch_space(&module, rank, ct_ggsw_rhs.size())
+        GLWECiphertextFourier::decrypt_scratch_space(&module, ct_ggsw_lhs_out.size())
-            | GLWECiphertextFourier::decrypt_scratch_space(&module, ct_ggsw_lhs_out.size())
             | GGSWCiphertext::encrypt_sk_scratch_space(&module, rank, ct_ggsw_lhs_in.size())
             | GGSWCiphertext::external_product_scratch_space(
                 &module,

core/src/test_fft64/glwe.rs

@@ -1,6 +1,6 @@
 use base2k::{
     Decoding, Encoding, FFT64, FillUniform, Module, ScalarZnx, ScalarZnxAlloc, ScratchOwned, Stats, VecZnxOps, VecZnxToMut,
-    ZnxView, ZnxViewMut, ZnxZero,
+    ZnxViewMut, ZnxZero,
 };
 use itertools::izip;
 use sampling::source::Source;
@@ -75,6 +75,22 @@ fn external_product_inplace() {
     });
 }
 
+#[test]
+fn automorphism_inplace() {
+    (1..4).for_each(|rank| {
+        println!("test automorphism_inplace rank: {}", rank);
+        test_automorphism_inplace(12, 12, -5, 60, 60, rank, 3.2);
+    });
+}
+
+#[test]
+fn automorphism() {
+    (1..4).for_each(|rank| {
+        println!("test automorphism rank: {}", rank);
+        test_automorphism(12, 12, -5, 60, 45, 60, rank, 3.2);
+    });
+}
+
 fn test_encrypt_sk(log_n: usize, basek: usize, k_ct: usize, k_pt: usize, sigma: f64, rank: usize) {
     let module: Module<FFT64> = Module::<FFT64>::new(1 << log_n);
 
@@ -416,14 +432,6 @@ fn test_keyswitch_inplace(log_n: usize, basek: usize, k_ksk: usize, k_ct: usize,
     );
 }
 
-#[test]
-fn automorphism() {
-    (1..4).for_each(|rank| {
-        println!("test automorphism rank: {}", rank);
-        test_automorphism(12, 12, -5, 60, 45, 60, rank, 3.2);
-    });
-}
-
 fn test_automorphism(
     log_n: usize,
     basek: usize,
@@ -515,14 +523,6 @@ fn test_automorphism(
     );
 }
 
-#[test]
-fn automorphism_inplace() {
-    (1..4).for_each(|rank| {
-        println!("test automorphism_inplace rank: {}", rank);
-        test_automorphism_inplace(12, 12, -5, 60, 60, rank, 3.2);
-    });
-}
-
 fn test_automorphism_inplace(log_n: usize, basek: usize, p: i64, k_autokey: usize, k_ct: usize, rank: usize, sigma: f64) {
     let module: Module<FFT64> = Module::<FFT64>::new(1 << log_n);
     let rows: usize = (k_ct + basek - 1) / basek;

core/src/test_fft64/mod.rs

@@ -3,3 +3,4 @@ mod gglwe;
 mod ggsw;
 mod glwe;
 mod glwe_fourier;
+mod tensor_key;

core/src/test_fft64/tensor_key.rs

@@ -0,0 +1,77 @@
+use base2k::{FFT64, Module, ScalarZnx, ScalarZnxDftAlloc, ScalarZnxDftOps, ScratchOwned, Stats, VecZnxDftOps, VecZnxOps};
+use sampling::source::Source;
+
+use crate::{
+    elem::{GetRow, Infos},
+    glwe_ciphertext_fourier::GLWECiphertextFourier,
+    glwe_plaintext::GLWEPlaintext,
+    keys::{SecretKey, SecretKeyFourier},
+    tensor_key::TensorKey,
+};
+
+#[test]
+fn encrypt_sk() {
+    (1..4).for_each(|rank| {
+        println!("test encrypt_sk rank: {}", rank);
+        test_encrypt_sk(12, 16, 54, 3.2, rank);
+    });
+}
+
+fn test_encrypt_sk(log_n: usize, basek: usize, k: usize, sigma: f64, rank: usize) {
+    let module: Module<FFT64> = Module::<FFT64>::new(1 << log_n);
+
+    let rows: usize = (k + basek - 1) / basek;
+
+    let mut tensor_key: TensorKey<Vec<u8>, FFT64> = TensorKey::new(&module, basek, k, rows, rank);
+
+    let mut source_xs: Source = Source::new([0u8; 32]);
+    let mut source_xe: Source = Source::new([0u8; 32]);
+    let mut source_xa: Source = Source::new([0u8; 32]);
+
+    let mut scratch: ScratchOwned = ScratchOwned::new(TensorKey::encrypt_sk_scratch_space(
+        &module,
+        rank,
+        tensor_key.size(),
+    ));
+
+    let mut sk: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
+    sk.fill_ternary_prob(0.5, &mut source_xs);
+
+    let mut sk_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
+    sk_dft.dft(&module, &sk);
+
+    tensor_key.encrypt_sk(
+        &module,
+        &sk_dft,
+        &mut source_xa,
+        &mut source_xe,
+        sigma,
+        scratch.borrow(),
+    );
+
+    let mut ct_glwe_fourier: GLWECiphertextFourier<Vec<u8>, FFT64> = GLWECiphertextFourier::new(&module, basek, k, rank);
+    let mut pt: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, basek, k);
+
+    (0..rank).for_each(|i| {
+        (0..rank).for_each(|j| {
+            let mut sk_ij_dft: base2k::ScalarZnxDft<Vec<u8>, FFT64> = module.new_scalar_znx_dft(1);
+            module.svp_apply(&mut sk_ij_dft, 0, &sk_dft.data, i, &sk_dft.data, j);
+            let sk_ij: ScalarZnx<Vec<u8>> = module
+                .vec_znx_idft_consume(sk_ij_dft.as_vec_znx_dft())
+                .to_vec_znx_small()
+                .to_scalar_znx();
+
+            (0..tensor_key.rank_in()).for_each(|col_i| {
+                (0..tensor_key.rows()).for_each(|row_i| {
+                    tensor_key
+                        .at(i, j)
+                        .get_row(&module, row_i, col_i, &mut ct_glwe_fourier);
+                    ct_glwe_fourier.decrypt(&module, &mut pt, &sk_dft, scratch.borrow());
+                    module.vec_znx_sub_scalar_inplace(&mut pt, 0, row_i, &sk_ij, col_i);
+                    let std_pt: f64 = pt.data.std(0, basek) * (k as f64).exp2();
+                    assert!((sigma - std_pt).abs() <= 0.2, "{} {}", sigma, std_pt);
+                });
+            });
+        })
+    })
+}