wip

rlwe/src/trace.rs

@@ -0,0 +1,112 @@
+use crate::{automorphism::AutomorphismKey, ciphertext::Ciphertext, elem::ElemCommon};
+use base2k::{
+    Module, VecZnx, VecZnxBig, VecZnxBigOps, VecZnxDft, VecZnxDftOps, VecZnxOps, VmpPMatOps,
+    assert_alignement,
+};
+use std::collections::HashMap;
+
+pub fn trace_tmp_bytes(
+    module: &Module,
+    c_cols: usize,
+    a_cols: usize,
+    b_rows: usize,
+    b_cols: usize,
+) -> usize {
+    return module.vmp_apply_dft_to_dft_tmp_bytes(c_cols, a_cols, b_rows, b_cols)
+        + 2 * module.bytes_of_vec_znx_dft(std::cmp::min(c_cols, a_cols));
+}
+
+pub fn trace_inplace(
+    module: &Module,
+    a: &mut Ciphertext<VecZnx>,
+    start: usize,
+    end: usize,
+    b: HashMap<i64, AutomorphismKey>,
+    tmp_bytes: &mut [u8],
+) {
+    let cols: usize = a.cols();
+
+    let b_rows: usize;
+    let b_cols: usize;
+
+    if let Some((_, key)) = b.iter().next() {
+        b_rows = key.value.rows();
+        b_cols = key.value.cols();
+    } else {
+        panic!("b: HashMap<i64, AutomorphismKey>, is empty")
+    }
+
+    #[cfg(debug_assertions)]
+    {
+        assert!(start <= end);
+        assert!(end <= module.n());
+        assert!(tmp_bytes.len() >= trace_tmp_bytes(module, cols, cols, b_rows, b_cols));
+        assert_alignement(tmp_bytes.as_ptr());
+    }
+
+    let cols: usize = std::cmp::min(b_cols, a.cols());
+
+    let (tmp_bytes_b1_dft, tmp_bytes) = tmp_bytes.split_at_mut(module.bytes_of_vec_znx_dft(cols));
+    let (tmp_bytes_res_dft, tmp_bytes) = tmp_bytes.split_at_mut(module.bytes_of_vec_znx_dft(cols));
+
+    let mut a1_dft: VecZnxDft = module.new_vec_znx_dft_from_bytes_borrow(cols, tmp_bytes_b1_dft);
+    let mut res_dft: VecZnxDft = module.new_vec_znx_dft_from_bytes_borrow(cols, tmp_bytes_res_dft);
+    let mut res_big: VecZnxBig = res_dft.as_vec_znx_big();
+
+    let log_base2k: usize = a.log_base2k();
+
+    (start..end).for_each(|i| {
+        a.at_mut(0).rsh(log_base2k, 1, tmp_bytes);
+        a.at_mut(1).rsh(log_base2k, 1, tmp_bytes);
+
+        let p: i64;
+        if i == 0 {
+            p = -1;
+        } else {
+            p = module.galois_element(1 << (i - 1));
+        }
+
+        if let Some(key) = b.get(&p) {
+            module.vec_znx_dft(&mut a1_dft, a.at(1));
+
+            // a[0] = NORMALIZE(a[0] + AUTO(a[0] + IDFT(<DFT(a[1]), key[0]>)))
+            module.vmp_apply_dft_to_dft(&mut res_dft, &a1_dft, key.value.at(0), tmp_bytes);
+            module.vec_znx_idft_tmp_a(&mut res_big, &mut res_dft);
+            module.vec_znx_big_add_small_inplace(&mut res_big, a.at(0));
+            module.vec_znx_big_automorphism_inplace(p, &mut res_big);
+            module.vec_znx_big_add_small_inplace(&mut res_big, a.at(0));
+            module.vec_znx_big_normalize(a.log_base2k(), a.at_mut(0), &mut res_big, tmp_bytes);
+
+            // a[1] = NORMALIZE(a[1] + AUTO(IDFT(<DFT(a[1]), key[1]>)))
+            module.vmp_apply_dft_to_dft(&mut res_dft, &a1_dft, key.value.at(1), tmp_bytes);
+            module.vec_znx_idft_tmp_a(&mut res_big, &mut res_dft);
+            module.vec_znx_big_automorphism_inplace(p, &mut res_big);
+            module.vec_znx_big_add_small_inplace(&mut res_big, a.at(1));
+            module.vec_znx_big_normalize(a.log_base2k(), a.at_mut(1), &mut res_big, tmp_bytes);
+        } else {
+            panic!("b[{}] is empty", p)
+        }
+    })
+}
+
+#[cfg(test)]
+mod test {
+    use crate::{
+        ciphertext::{Ciphertext, new_gadget_ciphertext},
+        decryptor::decrypt_rlwe,
+        elem::{Elem, ElemCommon, ElemVecZnx},
+        encryptor::encrypt_grlwe_sk,
+        gadget_product::gadget_product_core,
+        keys::SecretKey,
+        parameters::{Parameters, ParametersLiteral},
+        plaintext::Plaintext,
+    };
+    use base2k::{
+        BACKEND, Infos, Sampling, SvpPPolOps, VecZnx, VecZnxBig, VecZnxBigOps, VecZnxDft,
+        VecZnxDftOps, VecZnxOps, VmpPMat, alloc_aligned_u8,
+    };
+    use sampling::source::{Source, new_seed};
+
+    #[test]
+    fn test_trace_inplace() {}
+}