poulpy_core/conversion/
lwe_to_glwe.rs

1use poulpy_hal::{
2    api::ScratchTakeBasic,
3    layouts::{Backend, DataMut, Module, Scratch, VecZnx, ZnxView, ZnxViewMut, ZnxZero},
4};
5
6use crate::{
7    GLWEKeyswitch, ScratchTakeCore,
8    layouts::{GGLWEInfos, GGLWEPreparedToRef, GLWE, GLWEInfos, GLWELayout, GLWEToMut, LWE, LWEInfos, LWEToRef},
9};
10
11impl<BE: Backend> GLWEFromLWE<BE> for Module<BE> where Self: GLWEKeyswitch<BE> {}
12
13pub trait GLWEFromLWE<BE: Backend>
14where
15    Self: GLWEKeyswitch<BE>,
16{
17    fn glwe_from_lwe_tmp_bytes<R, A, K>(&self, glwe_infos: &R, lwe_infos: &A, key_infos: &K) -> usize
18    where
19        R: GLWEInfos,
20        A: LWEInfos,
21        K: GGLWEInfos,
22    {
23        let ct: usize = GLWE::bytes_of(
24            self.n().into(),
25            key_infos.base2k(),
26            lwe_infos.k().max(glwe_infos.k()),
27            1u32.into(),
28        );
29
30        let ks: usize = self.glwe_keyswitch_tmp_bytes(glwe_infos, glwe_infos, key_infos);
31        if lwe_infos.base2k() == key_infos.base2k() {
32            ct + ks
33        } else {
34            let a_conv = VecZnx::bytes_of(self.n(), 1, lwe_infos.size()) + self.vec_znx_normalize_tmp_bytes();
35            ct + a_conv + ks
36        }
37    }
38
39    fn glwe_from_lwe<R, A, K>(&self, res: &mut R, lwe: &A, ksk: &K, scratch: &mut Scratch<BE>)
40    where
41        R: GLWEToMut,
42        A: LWEToRef,
43        K: GGLWEPreparedToRef<BE> + GGLWEInfos,
44        Scratch<BE>: ScratchTakeCore<BE>,
45    {
46        let res: &mut GLWE<&mut [u8]> = &mut res.to_mut();
47        let lwe: &LWE<&[u8]> = &lwe.to_ref();
48
49        assert_eq!(res.n(), self.n() as u32);
50        assert_eq!(ksk.n(), self.n() as u32);
51        assert!(lwe.n() <= self.n() as u32);
52
53        let (mut glwe, scratch_1) = scratch.take_glwe(&GLWELayout {
54            n: ksk.n(),
55            base2k: ksk.base2k(),
56            k: lwe.k(),
57            rank: 1u32.into(),
58        });
59        glwe.data.zero();
60
61        let n_lwe: usize = lwe.n().into();
62
63        if lwe.base2k() == ksk.base2k() {
64            for i in 0..lwe.size() {
65                let data_lwe: &[i64] = lwe.data.at(0, i);
66                glwe.data.at_mut(0, i)[0] = data_lwe[0];
67                glwe.data.at_mut(1, i)[..n_lwe].copy_from_slice(&data_lwe[1..]);
68            }
69        } else {
70            let (mut a_conv, scratch_2) = scratch_1.take_vec_znx(self.n(), 1, lwe.size());
71            a_conv.zero();
72            for j in 0..lwe.size() {
73                let data_lwe: &[i64] = lwe.data.at(0, j);
74                a_conv.at_mut(0, j)[0] = data_lwe[0]
75            }
76
77            self.vec_znx_normalize(
78                ksk.base2k().into(),
79                &mut glwe.data,
80                0,
81                lwe.base2k().into(),
82                &a_conv,
83                0,
84                scratch_2,
85            );
86
87            a_conv.zero();
88            for j in 0..lwe.size() {
89                let data_lwe: &[i64] = lwe.data.at(0, j);
90                a_conv.at_mut(0, j)[..n_lwe].copy_from_slice(&data_lwe[1..]);
91            }
92
93            self.vec_znx_normalize(
94                ksk.base2k().into(),
95                &mut glwe.data,
96                1,
97                lwe.base2k().into(),
98                &a_conv,
99                0,
100                scratch_2,
101            );
102        }
103
104        self.glwe_keyswitch(res, &glwe, ksk, scratch_1);
105    }
106}
107
108impl GLWE<Vec<u8>> {
109    pub fn from_lwe_tmp_bytes<R, A, K, M, BE: Backend>(module: &M, glwe_infos: &R, lwe_infos: &A, key_infos: &K) -> usize
110    where
111        R: GLWEInfos,
112        A: LWEInfos,
113        K: GGLWEInfos,
114        M: GLWEFromLWE<BE>,
115    {
116        module.glwe_from_lwe_tmp_bytes(glwe_infos, lwe_infos, key_infos)
117    }
118}
119
120impl<D: DataMut> GLWE<D> {
121    pub fn from_lwe<A, K, M, BE: Backend>(&mut self, module: &M, lwe: &A, ksk: &K, scratch: &mut Scratch<BE>)
122    where
123        M: GLWEFromLWE<BE>,
124        A: LWEToRef,
125        K: GGLWEPreparedToRef<BE> + GGLWEInfos,
126        Scratch<BE>: ScratchTakeCore<BE>,
127    {
128        module.glwe_from_lwe(self, lwe, ksk, scratch);
129    }
130}
poulpy_core/conversion/lwe_to_glwe.rs

poulpy_core/conversion/
lwe_to_glwe.rs
