fixed standard binary cggi blind rotation & fixed GLWECiphertext::external_product_scratch_space returning too small values

core/src/blind_rotation/ccgi.rs

@@ -8,21 +8,24 @@ use itertools::izip;
 use crate::{
     GLWECiphertext, GLWECiphertextToMut, GLWEOps, Infos, LWECiphertext, ScratchCore,
     blind_rotation::{key::BlindRotationKeyCGGI, lut::LookUpTable},
+    dist::Distribution,
     lwe::ciphertext::LWECiphertextToRef,
 };
 
 pub fn cggi_blind_rotate_scratch_space(
     module: &Module<FFT64>,
+    block_size: usize,
     extension_factor: usize,
     basek: usize,
-    k_lut: usize,
+    k_res: usize,
     k_brk: usize,
     rows: usize,
     rank: usize,
 ) -> usize {
-    let cols: usize = rank + 1;
     let brk_size: usize = k_brk.div_ceil(basek);
 
+    if block_size > 1 {
+        let cols: usize = rank + 1;
         let acc_dft: usize = module.bytes_of_vec_znx_dft(cols, rows) * extension_factor;
         let acc_big: usize = module.bytes_of_vec_znx_big(1, brk_size);
         let vmp_res: usize = module.bytes_of_vec_znx_dft(cols, brk_size) * extension_factor;
@@ -33,7 +36,7 @@ pub fn cggi_blind_rotate_scratch_space(
 
         let acc: usize;
         if extension_factor > 1 {
-        acc = module.bytes_of_vec_znx(cols, k_lut.div_ceil(basek)) * extension_factor;
+            acc = module.bytes_of_vec_znx(cols, k_res.div_ceil(basek)) * extension_factor;
         } else {
             acc = 0;
         }
@@ -45,6 +48,10 @@ pub fn cggi_blind_rotate_scratch_space(
             + xai_plus_y
             + xai_plus_y_dft
             + (vmp | (acc_big + (module.vec_znx_big_normalize_tmp_bytes() | module.vec_znx_idft_tmp_bytes())));
+    } else {
+        2 * GLWECiphertext::bytes_of(module, basek, k_res, rank)
+            + GLWECiphertext::external_product_scratch_space(module, basek, k_res, k_res, k_brk, 1, rank)
+    }
 }
 
 pub fn cggi_blind_rotate<DataRes, DataIn>(
@@ -58,12 +65,20 @@ pub fn cggi_blind_rotate<DataRes, DataIn>(
     DataRes: AsRef<[u8]> + AsMut<[u8]>,
     DataIn: AsRef<[u8]>,
 {
+    match brk.dist {
+        Distribution::BinaryBlock(_) | Distribution::BinaryFixed(_) | Distribution::BinaryProb(_) | Distribution::ZERO => {
             if lut.extension_factor() > 1 {
                 cggi_blind_rotate_block_binary_extended(module, res, lwe, lut, brk, scratch);
             } else if brk.block_size() > 1 {
                 cggi_blind_rotate_block_binary(module, res, lwe, lut, brk, scratch);
             } else {
-        cggi_blind_rotate_standard(module, res, lwe, lut, brk, scratch);
+                cggi_blind_rotate_binary_standard(module, res, lwe, lut, brk, scratch);
+            }
+        }
+        // TODO: ternary distribution ?
+        _ => panic!(
+            "invalid BlindRotationKeyCGGI distribution: must be BinaryBlock, BinaryFixed or BinaryProb (or ZERO for debugging)"
+        ),
     }
 }
 
@@ -322,7 +337,7 @@ pub(crate) fn cggi_blind_rotate_block_binary<DataRes, DataIn>(
     });
 }
 
-pub(crate) fn cggi_blind_rotate_standard<DataRes, DataIn>(
+pub(crate) fn cggi_blind_rotate_binary_standard<DataRes, DataIn>(
     module: &Module<FFT64>,
     res: &mut GLWECiphertext<DataRes>,
     lwe: &LWECiphertext<DataIn>,

core/src/blind_rotation/test_fft64/cggi.rs

@@ -33,7 +33,8 @@ fn blind_rotatio_test(n_lwe: usize, block_size: usize, extension_factor: usize)
     let k_lwe: usize = 24;
     let k_brk: usize = 3 * basek;
     let rows_brk: usize = 2; // Ensures first limb is noise-free.
-    let k_lut: usize = 2 * basek;
+    let k_lut: usize = 1 * basek;
+    let k_res: usize = 2 * basek;
     let rank: usize = 1;
 
     let message_modulus: usize = 1 << 4;
@@ -55,9 +56,10 @@ fn blind_rotatio_test(n_lwe: usize, block_size: usize, extension_factor: usize)
 
     let mut scratch_br: ScratchOwned = ScratchOwned::new(cggi_blind_rotate_scratch_space(
         &module,
+        block_size,
         extension_factor,
         basek,
-        k_lut,
+        k_res,
         k_brk,
         rows_brk,
         rank,
@@ -100,13 +102,13 @@ fn blind_rotatio_test(n_lwe: usize, block_size: usize, extension_factor: usize)
     let mut lut: LookUpTable = LookUpTable::alloc(&module, basek, k_lut, extension_factor);
     lut.set(&module, &f, message_modulus);
 
-    let mut res: GLWECiphertext<Vec<u8>> = GLWECiphertext::alloc(&module, basek, k_lut, rank);
+    let mut res: GLWECiphertext<Vec<u8>> = GLWECiphertext::alloc(&module, basek, k_res, rank);
 
     cggi_blind_rotate(&module, &mut res, &lwe, &lut, &brk, scratch_br.borrow());
 
     println!("out_mut.data: {}", res.data);
 
-    let mut pt_have: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::alloc(&module, basek, k_lut);
+    let mut pt_have: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::alloc(&module, basek, k_res);
 
     res.decrypt(&module, &mut pt_have, &sk_glwe_dft, scratch.borrow());
 

core/src/glwe/external_product.rs

@@ -14,7 +14,7 @@ impl GLWECiphertext<Vec<u8>> {
         digits: usize,
         rank: usize,
     ) -> usize {
-        let res_dft: usize = FourierGLWECiphertext::bytes_of(module, basek, k_out, rank);
+        let res_dft: usize = FourierGLWECiphertext::bytes_of(module, basek, k_ggsw, rank);
         let in_size: usize = k_in.div_ceil(basek).div_ceil(digits);
         let out_size: usize = k_out.div_ceil(basek);
         let ggsw_size: usize = k_ggsw.div_ceil(basek);