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poulpy/poulpy-core/src/encryption/glwe_to_lwe_ksk.rs
poulpy-core/src/encryption/glwe_to_lwe_ksk.rsRaw
 1use poulpy_hal::{
 2    api::{
 3        ScratchAvailable, SvpApplyDftToDftInplace, SvpPPolBytesOf, SvpPrepare, TakeScalarZnx, TakeVecZnx, TakeVecZnxDft,
 4        VecZnxAddInplace, VecZnxAddNormal, VecZnxAddScalarInplace, VecZnxAutomorphismInplace, VecZnxBigNormalize, VecZnxDftApply,
 5        VecZnxDftBytesOf, VecZnxFillUniform, VecZnxIdftApplyConsume, VecZnxNormalize, VecZnxNormalizeInplace,
 6        VecZnxNormalizeTmpBytes, VecZnxSub, VecZnxSubInplace, VecZnxSwitchRing,
 7    },
 8    layouts::{Backend, DataMut, DataRef, Module, Scratch, ZnxView, ZnxViewMut, ZnxZero},
 9    source::Source,
10};
11
12use crate::{
13    TakeGLWESecret, TakeGLWESecretPrepared,
14    layouts::{
15        GGLWEInfos, GLWESecret, GLWESwitchingKey, GLWEToLWESwitchingKey, LWEInfos, LWESecret, Rank, prepared::GLWESecretPrepared,
16    },
17};
18
19impl GLWEToLWESwitchingKey<Vec<u8>> {
20    pub fn encrypt_sk_scratch_space<B: Backend, A>(module: &Module<B>, infos: &A) -> usize
21    where
22        A: GGLWEInfos,
23        Module<B>: SvpPPolBytesOf + VecZnxNormalizeTmpBytes + VecZnxDftBytesOf + VecZnxNormalizeTmpBytes,
24    {
25        GLWESecretPrepared::bytes_of(module, infos.rank_in())
26            + (GLWESwitchingKey::encrypt_sk_scratch_space(module, infos) | GLWESecret::bytes_of(infos.n(), infos.rank_in()))
27    }
28}
29
30impl<D: DataMut> GLWEToLWESwitchingKey<D> {
31    #[allow(clippy::too_many_arguments)]
32    pub fn encrypt_sk<DLwe, DGlwe, B: Backend>(
33        &mut self,
34        module: &Module<B>,
35        sk_lwe: &LWESecret<DLwe>,
36        sk_glwe: &GLWESecret<DGlwe>,
37        source_xa: &mut Source,
38        source_xe: &mut Source,
39        scratch: &mut Scratch<B>,
40    ) where
41        DLwe: DataRef,
42        DGlwe: DataRef,
43        Module<B>: VecZnxAutomorphismInplace<B>
44            + VecZnxAddScalarInplace
45            + VecZnxDftBytesOf
46            + VecZnxBigNormalize<B>
47            + VecZnxDftApply<B>
48            + SvpApplyDftToDftInplace<B>
49            + VecZnxIdftApplyConsume<B>
50            + VecZnxNormalizeTmpBytes
51            + VecZnxFillUniform
52            + VecZnxSubInplace
53            + VecZnxAddInplace
54            + VecZnxNormalizeInplace<B>
55            + VecZnxAddNormal
56            + VecZnxNormalize<B>
57            + VecZnxSub
58            + SvpPrepare<B>
59            + VecZnxSwitchRing
60            + SvpPPolBytesOf,
61        Scratch<B>: TakeVecZnxDft<B> + ScratchAvailable + TakeVecZnx + TakeScalarZnx + TakeGLWESecretPrepared<B>,
62    {
63        #[cfg(debug_assertions)]
64        {
65            assert!(sk_lwe.n().0 <= module.n() as u32);
66        }
67
68        let (mut sk_lwe_as_glwe, scratch_1) = scratch.take_glwe_secret(sk_glwe.n(), Rank(1));
69        sk_lwe_as_glwe.data.zero();
70        sk_lwe_as_glwe.data.at_mut(0, 0)[..sk_lwe.n().into()].copy_from_slice(sk_lwe.data.at(0, 0));
71        module.vec_znx_automorphism_inplace(-1, &mut sk_lwe_as_glwe.data.as_vec_znx_mut(), 0, scratch_1);
72
73        self.0.encrypt_sk(
74            module,
75            sk_glwe,
76            &sk_lwe_as_glwe,
77            source_xa,
78            source_xe,
79            scratch_1,
80        );
81    }
82}