poulpy_core/conversion/
glwe_to_lwe.rs

1use poulpy_hal::{
2    api::ModuleN,
3    layouts::{Backend, DataMut, Module, Scratch, ZnxView, ZnxViewMut, ZnxZero},
4};
5
6use crate::{
7    GLWEKeyswitch, ScratchTakeCore,
8    layouts::{GGLWEInfos, GGLWEPreparedToRef, GLWE, GLWEInfos, GLWELayout, GLWEToRef, LWE, LWEInfos, LWEToMut, Rank},
9};
10
11pub trait LWESampleExtract
12where
13    Self: ModuleN,
14{
15    fn lwe_sample_extract<R, A>(&self, res: &mut R, a: &A)
16    where
17        R: LWEToMut,
18        A: GLWEToRef,
19    {
20        let res: &mut LWE<&mut [u8]> = &mut res.to_mut();
21        let a: &GLWE<&[u8]> = &a.to_ref();
22
23        assert!(res.n() <= a.n());
24        assert_eq!(a.n(), self.n() as u32);
25        assert!(res.base2k() == a.base2k());
26
27        let min_size: usize = res.size().min(a.size());
28        let n: usize = res.n().into();
29
30        res.data.zero();
31        (0..min_size).for_each(|i| {
32            let data_lwe: &mut [i64] = res.data.at_mut(0, i);
33            data_lwe[0] = a.data.at(0, i)[0];
34            data_lwe[1..].copy_from_slice(&a.data.at(1, i)[..n]);
35        });
36    }
37}
38
39impl<BE: Backend> LWESampleExtract for Module<BE> where Self: ModuleN {}
40impl<BE: Backend> LWEFromGLWE<BE> for Module<BE> where Self: GLWEKeyswitch<BE> + LWESampleExtract {}
41
42pub trait LWEFromGLWE<BE: Backend>
43where
44    Self: GLWEKeyswitch<BE> + LWESampleExtract,
45{
46    fn lwe_from_glwe_tmp_bytes<R, A, K>(&self, lwe_infos: &R, glwe_infos: &A, key_infos: &K) -> usize
47    where
48        R: LWEInfos,
49        A: GLWEInfos,
50        K: GGLWEInfos,
51    {
52        let res_infos: GLWELayout = GLWELayout {
53            n: self.n().into(),
54            base2k: lwe_infos.base2k(),
55            k: lwe_infos.k(),
56            rank: Rank(1),
57        };
58
59        GLWE::bytes_of(
60            self.n().into(),
61            lwe_infos.base2k(),
62            lwe_infos.k(),
63            1u32.into(),
64        ) + self.glwe_keyswitch_tmp_bytes(&res_infos, glwe_infos, key_infos)
65    }
66
67    fn lwe_from_glwe<R, A, K>(&self, res: &mut R, a: &A, key: &K, scratch: &mut Scratch<BE>)
68    where
69        R: LWEToMut,
70        A: GLWEToRef,
71        K: GGLWEPreparedToRef<BE> + GGLWEInfos,
72        Scratch<BE>: ScratchTakeCore<BE>,
73    {
74        let res: &mut LWE<&mut [u8]> = &mut res.to_mut();
75        let a: &GLWE<&[u8]> = &a.to_ref();
76
77        assert_eq!(a.n(), self.n() as u32);
78        assert_eq!(key.n(), self.n() as u32);
79        assert!(res.n() <= self.n() as u32);
80
81        let glwe_layout: GLWELayout = GLWELayout {
82            n: self.n().into(),
83            base2k: res.base2k(),
84            k: res.k(),
85            rank: Rank(1),
86        };
87
88        let (mut tmp_glwe, scratch_1) = scratch.take_glwe(&glwe_layout);
89        self.glwe_keyswitch(&mut tmp_glwe, a, key, scratch_1);
90        self.lwe_sample_extract(res, &tmp_glwe);
91    }
92}
93
94impl LWE<Vec<u8>> {
95    pub fn from_glwe_tmp_bytes<R, A, K, M, BE: Backend>(module: &M, lwe_infos: &R, glwe_infos: &A, key_infos: &K) -> usize
96    where
97        R: LWEInfos,
98        A: GLWEInfos,
99        K: GGLWEInfos,
100        M: LWEFromGLWE<BE>,
101    {
102        module.lwe_from_glwe_tmp_bytes(lwe_infos, glwe_infos, key_infos)
103    }
104}
105
106impl<D: DataMut> LWE<D> {
107    pub fn sample_extract<A, M>(&mut self, module: &M, a: &A)
108    where
109        A: GLWEToRef,
110        M: LWESampleExtract,
111    {
112        module.lwe_sample_extract(self, a);
113    }
114
115    pub fn from_glwe<A, K, M, BE: Backend>(&mut self, module: &M, a: &A, key: &K, scratch: &mut Scratch<BE>)
116    where
117        A: GLWEToRef,
118        K: GGLWEPreparedToRef<BE> + GGLWEInfos,
119        M: LWEFromGLWE<BE>,
120        Scratch<BE>: ScratchTakeCore<BE>,
121    {
122        module.lwe_from_glwe(self, a, key, scratch);
123    }
124}
poulpy_core/conversion/glwe_to_lwe.rs

poulpy_core/conversion/
glwe_to_lwe.rs
