1use std::collections::HashMap;
  2
  3use poulpy_hal::{
  4    api::{ScratchAvailable, ScratchOwnedAlloc, ScratchOwnedBorrow},
  5    layouts::{Backend, Module, Scratch, ScratchOwned},
  6    source::Source,
  7};
  8
  9use crate::{
 10    AutomorphismKeyEncryptSk, GLWEDecrypt, GLWEEncryptSk, GLWEPacker, GLWEPacking, GLWERotate, GLWESub, ScratchTakeCore,
 11    layouts::{
 12        AutomorphismKey, AutomorphismKeyLayout, GLWE, GLWEAutomorphismKeyPreparedFactory, GLWELayout, GLWEPlaintext, GLWESecret,
 13        GLWESecretPreparedFactory,
 14        prepared::{GLWEAutomorphismKeyPrepared, GLWESecretPrepared},
 15    },
 16};
 17
 18pub fn test_glwe_packing<BE: Backend>(module: &Module<BE>)
 19where
 20    Module<BE>: GLWEEncryptSk<BE>
 21        + AutomorphismKeyEncryptSk<BE>
 22        + GLWEAutomorphismKeyPreparedFactory<BE>
 23        + GLWEPacking<BE>
 24        + GLWESecretPreparedFactory<BE>
 25        + GLWESub
 26        + GLWEDecrypt<BE>
 27        + GLWERotate<BE>,
 28    ScratchOwned<BE>: ScratchOwnedAlloc<BE> + ScratchOwnedBorrow<BE>,
 29    Scratch<BE>: ScratchAvailable + ScratchTakeCore<BE>,
 30{
 31    let mut source_xs: Source = Source::new([0u8; 32]);
 32    let mut source_xe: Source = Source::new([0u8; 32]);
 33    let mut source_xa: Source = Source::new([0u8; 32]);
 34
 35    let n: usize = module.n();
 36    let base2k: usize = 18;
 37    let k_ct: usize = 36;
 38    let pt_k: usize = 18;
 39    let rank: usize = 3;
 40    let dsize: usize = 1;
 41    let k_ksk: usize = k_ct + base2k * dsize;
 42
 43    let dnum: usize = k_ct.div_ceil(base2k * dsize);
 44
 45    let glwe_out_infos: GLWELayout = GLWELayout {
 46        n: n.into(),
 47        base2k: base2k.into(),
 48        k: k_ct.into(),
 49        rank: rank.into(),
 50    };
 51
 52    let key_infos: AutomorphismKeyLayout = AutomorphismKeyLayout {
 53        n: n.into(),
 54        base2k: base2k.into(),
 55        k: k_ksk.into(),
 56        rank: rank.into(),
 57        dsize: dsize.into(),
 58        dnum: dnum.into(),
 59    };
 60
 61    let mut scratch: ScratchOwned<BE> = ScratchOwned::alloc(
 62        GLWE::encrypt_sk_tmp_bytes(module, &glwe_out_infos)
 63            | AutomorphismKey::encrypt_sk_tmp_bytes(module, &key_infos)
 64            | GLWEPacker::tmp_bytes(module, &glwe_out_infos, &key_infos),
 65    );
 66
 67    let mut sk: GLWESecret<Vec<u8>> = GLWESecret::alloc_from_infos(&glwe_out_infos);
 68    sk.fill_ternary_prob(0.5, &mut source_xs);
 69
 70    let mut sk_dft: GLWESecretPrepared<Vec<u8>, BE> = GLWESecretPrepared::alloc_from_infos(module, &sk);
 71    sk_dft.prepare(module, &sk);
 72
 73    let mut pt: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::alloc_from_infos(&glwe_out_infos);
 74    let mut data: Vec<i64> = vec![0i64; n];
 75    data.iter_mut().enumerate().for_each(|(i, x)| {
 76        *x = i as i64;
 77    });
 78
 79    pt.encode_vec_i64(&data, pt_k.into());
 80
 81    let gal_els: Vec<i64> = GLWEPacker::galois_elements(module);
 82
 83    let mut auto_keys: HashMap<i64, GLWEAutomorphismKeyPrepared<Vec<u8>, BE>> = HashMap::new();
 84    let mut tmp: AutomorphismKey<Vec<u8>> = AutomorphismKey::alloc_from_infos(&key_infos);
 85    gal_els.iter().for_each(|gal_el| {
 86        tmp.encrypt_sk(
 87            module,
 88            *gal_el,
 89            &sk,
 90            &mut source_xa,
 91            &mut source_xe,
 92            scratch.borrow(),
 93        );
 94        let mut atk_prepared: GLWEAutomorphismKeyPrepared<Vec<u8>, BE> =
 95            GLWEAutomorphismKeyPrepared::alloc_from_infos(module, &tmp);
 96        atk_prepared.prepare(module, &tmp, scratch.borrow());
 97        auto_keys.insert(*gal_el, atk_prepared);
 98    });
 99
100    let log_batch: usize = 0;
101
102    let mut packer: GLWEPacker = GLWEPacker::alloc(&glwe_out_infos, log_batch);
103
104    let mut ct: GLWE<Vec<u8>> = GLWE::alloc_from_infos(&glwe_out_infos);
105
106    ct.encrypt_sk(
107        module,
108        &pt,
109        &sk_dft,
110        &mut source_xa,
111        &mut source_xe,
112        scratch.borrow(),
113    );
114
115    let log_n: usize = module.log_n();
116
117    (0..n >> log_batch).for_each(|i| {
118        ct.encrypt_sk(
119            module,
120            &pt,
121            &sk_dft,
122            &mut source_xa,
123            &mut source_xe,
124            scratch.borrow(),
125        );
126
127        module.glwe_rotate_inplace(-(1 << log_batch), &mut pt, scratch.borrow()); // X^-batch * pt
128
129        if reverse_bits_msb(i, log_n as u32).is_multiple_of(5) {
130            packer.add(module, Some(&ct), &auto_keys, scratch.borrow());
131        } else {
132            packer.add(module, None::<&GLWE<Vec<u8>>>, &auto_keys, scratch.borrow())
133        }
134    });
135
136    let mut res: GLWE<Vec<u8>> = GLWE::alloc_from_infos(&glwe_out_infos);
137    packer.flush(module, &mut res);
138
139    let mut pt_want: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::alloc_from_infos(&glwe_out_infos);
140    let mut data: Vec<i64> = vec![0i64; n];
141    data.iter_mut().enumerate().for_each(|(i, x)| {
142        if i.is_multiple_of(5) {
143            *x = reverse_bits_msb(i, log_n as u32) as i64;
144        }
145    });
146
147    pt_want.encode_vec_i64(&data, pt_k.into());
148
149    res.decrypt(module, &mut pt, &sk_dft, scratch.borrow());
150
151    module.glwe_sub_inplace(&mut pt, &pt_want);
152
153    let noise_have: f64 = pt.std().log2();
154
155    assert!(
156        noise_have < -((k_ct - base2k) as f64),
157        "noise: {noise_have}"
158    );
159}
160
161#[inline(always)]
162fn reverse_bits_msb(x: usize, n: u32) -> usize {
163    x.reverse_bits() >> (usize::BITS - n)
164}