poulpy/core/src/glwe_ciphertext.rs
core/src/glwe_ciphertext.rsRaw
1use backend::{
2 AddNormal, Backend, FFT64, FillUniform, MatZnxDft, MatZnxDftOps, MatZnxDftScratch, MatZnxDftToRef, Module, ScalarZnxAlloc,
3 ScalarZnxDft, ScalarZnxDftAlloc, ScalarZnxDftOps, ScalarZnxDftToRef, Scratch, VecZnx, VecZnxAlloc, VecZnxBig, VecZnxBigAlloc,
4 VecZnxBigOps, VecZnxBigScratch, VecZnxDft, VecZnxDftAlloc, VecZnxDftOps, VecZnxDftToMut, VecZnxDftToRef, VecZnxOps,
5 VecZnxToMut, VecZnxToRef, ZnxInfos, ZnxZero,
6};
7use sampling::source::Source;
8
9use crate::{
10 SIX_SIGMA,
11 automorphism::AutomorphismKey,
12 elem::{Infos, SetMetaData},
13 ggsw_ciphertext::GGSWCiphertext,
14 glwe_ciphertext_fourier::GLWECiphertextFourier,
15 glwe_plaintext::GLWEPlaintext,
16 keys::{GLWEPublicKey, SecretDistribution, SecretKeyFourier},
17 keyswitch_key::GLWESwitchingKey,
18 utils::derive_size,
19};
20
21pub struct GLWECiphertext<C> {
22 pub data: VecZnx<C>,
23 pub basek: usize,
24 pub k: usize,
25}
26
27impl GLWECiphertext<Vec<u8>> {
28 pub fn alloc<B: Backend>(module: &Module<B>, basek: usize, k: usize, rank: usize) -> Self {
29 Self {
30 data: module.new_vec_znx(rank + 1, derive_size(basek, k)),
31 basek,
32 k,
33 }
34 }
35}
36
37impl<T> Infos for GLWECiphertext<T> {
38 type Inner = VecZnx<T>;
39
40 fn inner(&self) -> &Self::Inner {
41 &self.data
42 }
43
44 fn basek(&self) -> usize {
45 self.basek
46 }
47
48 fn k(&self) -> usize {
49 self.k
50 }
51}
52
53impl<T> GLWECiphertext<T> {
54 pub fn rank(&self) -> usize {
55 self.cols() - 1
56 }
57}
58
59impl<C> VecZnxToMut for GLWECiphertext<C>
60where
61 VecZnx<C>: VecZnxToMut,
62{
63 fn to_mut(&mut self) -> VecZnx<&mut [u8]> {
64 self.data.to_mut()
65 }
66}
67
68impl<C> VecZnxToRef for GLWECiphertext<C>
69where
70 VecZnx<C>: VecZnxToRef,
71{
72 fn to_ref(&self) -> VecZnx<&[u8]> {
73 self.data.to_ref()
74 }
75}
76
77impl<C> GLWECiphertext<C>
78where
79 VecZnx<C>: VecZnxToRef,
80{
81 #[allow(dead_code)]
82 pub(crate) fn dft<R>(&self, module: &Module<FFT64>, res: &mut GLWECiphertextFourier<R, FFT64>)
83 where
84 VecZnxDft<R, FFT64>: VecZnxDftToMut<FFT64> + ZnxInfos,
85 {
86 #[cfg(debug_assertions)]
87 {
88 assert_eq!(self.rank(), res.rank());
89 assert_eq!(self.basek(), res.basek())
90 }
91
92 (0..self.rank() + 1).for_each(|i| {
93 module.vec_znx_dft(res, i, self, i);
94 })
95 }
96}
97
98impl GLWECiphertext<Vec<u8>> {
99 pub fn encrypt_sk_scratch_space(module: &Module<FFT64>, ct_size: usize) -> usize {
100 module.vec_znx_big_normalize_tmp_bytes() + module.bytes_of_vec_znx_dft(1, ct_size) + module.bytes_of_vec_znx(1, ct_size)
101 }
102 pub fn encrypt_pk_scratch_space(module: &Module<FFT64>, pk_size: usize) -> usize {
103 ((module.bytes_of_vec_znx_dft(1, pk_size) + module.bytes_of_vec_znx_big(1, pk_size)) | module.bytes_of_scalar_znx(1))
104 + module.bytes_of_scalar_znx_dft(1)
105 + module.vec_znx_big_normalize_tmp_bytes()
106 }
107
108 pub fn decrypt_scratch_space(module: &Module<FFT64>, ct_size: usize) -> usize {
109 (module.vec_znx_big_normalize_tmp_bytes() | module.bytes_of_vec_znx_dft(1, ct_size))
110 + module.bytes_of_vec_znx_big(1, ct_size)
111 }
112
113 pub fn keyswitch_scratch_space(
114 module: &Module<FFT64>,
115 out_size: usize,
116 out_rank: usize,
117 in_size: usize,
118 in_rank: usize,
119 ksk_size: usize,
120 ) -> usize {
121 let res_dft: usize = module.bytes_of_vec_znx_dft(out_rank + 1, ksk_size);
122 let vmp: usize = module.vmp_apply_tmp_bytes(out_size, in_size, in_size, in_rank, out_rank + 1, ksk_size)
123 + module.bytes_of_vec_znx_dft(in_rank, in_size);
124 let normalize: usize = module.vec_znx_big_normalize_tmp_bytes();
125
126 return res_dft + (vmp | normalize);
127 }
128
129 pub fn keyswitch_from_fourier_scratch_space(
130 module: &Module<FFT64>,
131 out_size: usize,
132 out_rank: usize,
133 in_size: usize,
134 in_rank: usize,
135 ksk_size: usize,
136 ) -> usize {
137 let res_dft = module.bytes_of_vec_znx_dft(out_rank + 1, ksk_size);
138
139 let vmp: usize = module.vmp_apply_tmp_bytes(out_size, in_size, in_size, in_rank, out_rank + 1, ksk_size)
140 + module.bytes_of_vec_znx_dft(in_rank, in_size);
141
142 let norm: usize = module.vec_znx_big_normalize_tmp_bytes();
143
144 res_dft + (vmp | norm)
145 }
146
147 pub fn keyswitch_inplace_scratch_space(module: &Module<FFT64>, out_size: usize, out_rank: usize, ksk_size: usize) -> usize {
148 GLWECiphertext::keyswitch_scratch_space(module, out_size, out_rank, out_size, out_rank, ksk_size)
149 }
150
151 pub fn automorphism_scratch_space(
152 module: &Module<FFT64>,
153 out_size: usize,
154 out_rank: usize,
155 in_size: usize,
156 autokey_size: usize,
157 ) -> usize {
158 GLWECiphertext::keyswitch_scratch_space(module, out_size, out_rank, in_size, out_rank, autokey_size)
159 }
160
161 pub fn automorphism_inplace_scratch_space(
162 module: &Module<FFT64>,
163 out_size: usize,
164 out_rank: usize,
165 autokey_size: usize,
166 ) -> usize {
167 GLWECiphertext::keyswitch_scratch_space(module, out_size, out_rank, out_size, out_rank, autokey_size)
168 }
169
170 pub fn external_product_scratch_space(
171 module: &Module<FFT64>,
172 out_size: usize,
173 out_rank: usize,
174 in_size: usize,
175 ggsw_size: usize,
176 ) -> usize {
177 let res_dft: usize = module.bytes_of_vec_znx_dft(out_rank + 1, ggsw_size);
178 let vmp: usize = module.bytes_of_vec_znx_dft(out_rank + 1, in_size)
179 + module.vmp_apply_tmp_bytes(
180 out_size,
181 in_size,
182 in_size, // rows
183 out_rank + 1, // cols in
184 out_rank + 1, // cols out
185 ggsw_size,
186 );
187 let normalize: usize = module.vec_znx_big_normalize_tmp_bytes();
188
189 res_dft + (vmp | normalize)
190 }
191
192 pub fn external_product_inplace_scratch_space(
193 module: &Module<FFT64>,
194 out_size: usize,
195 out_rank: usize,
196 ggsw_size: usize,
197 ) -> usize {
198 GLWECiphertext::external_product_scratch_space(module, out_size, out_rank, out_size, ggsw_size)
199 }
200}
201
202impl<DataSelf> SetMetaData for GLWECiphertext<DataSelf>
203where
204 VecZnx<DataSelf>: VecZnxToMut,
205{
206 fn set_k(&mut self, k: usize) {
207 self.k = k
208 }
209
210 fn set_basek(&mut self, basek: usize) {
211 self.basek = basek
212 }
213}
214
215impl<DataSelf> GLWECiphertext<DataSelf>
216where
217 VecZnx<DataSelf>: VecZnxToMut,
218{
219 pub fn encrypt_sk<DataPt, DataSk>(
220 &mut self,
221 module: &Module<FFT64>,
222 pt: &GLWEPlaintext<DataPt>,
223 sk_dft: &SecretKeyFourier<DataSk, FFT64>,
224 source_xa: &mut Source,
225 source_xe: &mut Source,
226 sigma: f64,
227 scratch: &mut Scratch,
228 ) where
229 VecZnx<DataPt>: VecZnxToRef,
230 ScalarZnxDft<DataSk, FFT64>: ScalarZnxDftToRef<FFT64>,
231 {
232 self.encrypt_sk_private(
233 module,
234 Some((pt, 0)),
235 sk_dft,
236 source_xa,
237 source_xe,
238 sigma,
239 scratch,
240 );
241 }
242
243 pub fn encrypt_zero_sk<DataSk>(
244 &mut self,
245 module: &Module<FFT64>,
246 sk_dft: &SecretKeyFourier<DataSk, FFT64>,
247 source_xa: &mut Source,
248 source_xe: &mut Source,
249 sigma: f64,
250 scratch: &mut Scratch,
251 ) where
252 ScalarZnxDft<DataSk, FFT64>: ScalarZnxDftToRef<FFT64>,
253 {
254 self.encrypt_sk_private(module, None, sk_dft, source_xa, source_xe, sigma, scratch);
255 }
256
257 pub fn encrypt_pk<DataPt, DataPk>(
258 &mut self,
259 module: &Module<FFT64>,
260 pt: &GLWEPlaintext<DataPt>,
261 pk: &GLWEPublicKey<DataPk, FFT64>,
262 source_xu: &mut Source,
263 source_xe: &mut Source,
264 sigma: f64,
265 scratch: &mut Scratch,
266 ) where
267 VecZnx<DataPt>: VecZnxToRef,
268 VecZnxDft<DataPk, FFT64>: VecZnxDftToRef<FFT64>,
269 {
270 self.encrypt_pk_private(
271 module,
272 Some((pt, 0)),
273 pk,
274 source_xu,
275 source_xe,
276 sigma,
277 scratch,
278 );
279 }
280
281 pub fn encrypt_zero_pk<DataPk>(
282 &mut self,
283 module: &Module<FFT64>,
284 pk: &GLWEPublicKey<DataPk, FFT64>,
285 source_xu: &mut Source,
286 source_xe: &mut Source,
287 sigma: f64,
288 scratch: &mut Scratch,
289 ) where
290 VecZnxDft<DataPk, FFT64>: VecZnxDftToRef<FFT64>,
291 {
292 self.encrypt_pk_private(module, None, pk, source_xu, source_xe, sigma, scratch);
293 }
294
295 pub fn automorphism<DataLhs, DataRhs>(
296 &mut self,
297 module: &Module<FFT64>,
298 lhs: &GLWECiphertext<DataLhs>,
299 rhs: &AutomorphismKey<DataRhs, FFT64>,
300 scratch: &mut Scratch,
301 ) where
302 VecZnx<DataLhs>: VecZnxToRef,
303 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
304 {
305 self.keyswitch(module, lhs, &rhs.key, scratch);
306 (0..self.rank() + 1).for_each(|i| {
307 module.vec_znx_automorphism_inplace(rhs.p(), self, i);
308 })
309 }
310
311 pub fn automorphism_inplace<DataRhs>(
312 &mut self,
313 module: &Module<FFT64>,
314 rhs: &AutomorphismKey<DataRhs, FFT64>,
315 scratch: &mut Scratch,
316 ) where
317 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
318 {
319 self.keyswitch_inplace(module, &rhs.key, scratch);
320 (0..self.rank() + 1).for_each(|i| {
321 module.vec_znx_automorphism_inplace(rhs.p(), self, i);
322 })
323 }
324
325 pub fn automorphism_add<DataLhs, DataRhs>(
326 &mut self,
327 module: &Module<FFT64>,
328 lhs: &GLWECiphertext<DataLhs>,
329 rhs: &AutomorphismKey<DataRhs, FFT64>,
330 scratch: &mut Scratch,
331 ) where
332 VecZnx<DataLhs>: VecZnxToRef,
333 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
334 {
335 Self::keyswitch_private::<_, _, 1>(self, rhs.p(), module, lhs, &rhs.key, scratch);
336 }
337
338 pub fn automorphism_add_inplace<DataRhs>(
339 &mut self,
340 module: &Module<FFT64>,
341 rhs: &AutomorphismKey<DataRhs, FFT64>,
342 scratch: &mut Scratch,
343 ) where
344 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
345 {
346 unsafe {
347 let self_ptr: *mut GLWECiphertext<DataSelf> = self as *mut GLWECiphertext<DataSelf>;
348 Self::keyswitch_private::<_, _, 1>(self, rhs.p(), module, &*self_ptr, &rhs.key, scratch);
349 }
350 }
351
352 pub fn automorphism_sub_ab<DataLhs, DataRhs>(
353 &mut self,
354 module: &Module<FFT64>,
355 lhs: &GLWECiphertext<DataLhs>,
356 rhs: &AutomorphismKey<DataRhs, FFT64>,
357 scratch: &mut Scratch,
358 ) where
359 VecZnx<DataLhs>: VecZnxToRef,
360 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
361 {
362 Self::keyswitch_private::<_, _, 2>(self, rhs.p(), module, lhs, &rhs.key, scratch);
363 }
364
365 pub fn automorphism_sub_ab_inplace<DataRhs>(
366 &mut self,
367 module: &Module<FFT64>,
368 rhs: &AutomorphismKey<DataRhs, FFT64>,
369 scratch: &mut Scratch,
370 ) where
371 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
372 {
373 unsafe {
374 let self_ptr: *mut GLWECiphertext<DataSelf> = self as *mut GLWECiphertext<DataSelf>;
375 Self::keyswitch_private::<_, _, 2>(self, rhs.p(), module, &*self_ptr, &rhs.key, scratch);
376 }
377 }
378
379 pub fn automorphism_sub_ba<DataLhs, DataRhs>(
380 &mut self,
381 module: &Module<FFT64>,
382 lhs: &GLWECiphertext<DataLhs>,
383 rhs: &AutomorphismKey<DataRhs, FFT64>,
384 scratch: &mut Scratch,
385 ) where
386 VecZnx<DataLhs>: VecZnxToRef,
387 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
388 {
389 Self::keyswitch_private::<_, _, 3>(self, rhs.p(), module, lhs, &rhs.key, scratch);
390 }
391
392 pub fn automorphism_sub_ba_inplace<DataRhs>(
393 &mut self,
394 module: &Module<FFT64>,
395 rhs: &AutomorphismKey<DataRhs, FFT64>,
396 scratch: &mut Scratch,
397 ) where
398 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
399 {
400 unsafe {
401 let self_ptr: *mut GLWECiphertext<DataSelf> = self as *mut GLWECiphertext<DataSelf>;
402 Self::keyswitch_private::<_, _, 3>(self, rhs.p(), module, &*self_ptr, &rhs.key, scratch);
403 }
404 }
405
406 pub(crate) fn keyswitch_from_fourier<DataLhs, DataRhs>(
407 &mut self,
408 module: &Module<FFT64>,
409 lhs: &GLWECiphertextFourier<DataLhs, FFT64>,
410 rhs: &GLWESwitchingKey<DataRhs, FFT64>,
411 scratch: &mut Scratch,
412 ) where
413 VecZnxDft<DataLhs, FFT64>: VecZnxDftToRef<FFT64>,
414 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
415 {
416 let basek: usize = self.basek();
417
418 #[cfg(debug_assertions)]
419 {
420 assert_eq!(lhs.rank(), rhs.rank_in());
421 assert_eq!(self.rank(), rhs.rank_out());
422 assert_eq!(self.basek(), basek);
423 assert_eq!(lhs.basek(), basek);
424 assert_eq!(rhs.n(), module.n());
425 assert_eq!(self.n(), module.n());
426 assert_eq!(lhs.n(), module.n());
427 assert!(
428 scratch.available()
429 >= GLWECiphertext::keyswitch_from_fourier_scratch_space(
430 module,
431 self.size(),
432 self.rank(),
433 lhs.size(),
434 lhs.rank(),
435 rhs.size(),
436 )
437 );
438 }
439
440 let cols_in: usize = rhs.rank_in();
441 let cols_out: usize = rhs.rank_out() + 1;
442
443 // Buffer of the result of VMP in DFT
444 let (mut res_dft, scratch1) = scratch.tmp_vec_znx_dft(module, cols_out, rhs.size()); // Todo optimise
445
446 {
447 // Applies VMP
448 let (mut ai_dft, scratch2) = scratch1.tmp_vec_znx_dft(module, cols_in, lhs.size());
449 (0..cols_in).for_each(|col_i| {
450 module.vec_znx_dft_copy(&mut ai_dft, col_i, lhs, col_i + 1);
451 });
452 module.vmp_apply(&mut res_dft, &ai_dft, rhs, scratch2);
453 }
454
455 module.vec_znx_dft_add_inplace(&mut res_dft, 0, lhs, 0);
456
457 // Switches result of VMP outside of DFT
458 let res_big: VecZnxBig<&mut [u8], FFT64> = module.vec_znx_idft_consume::<&mut [u8]>(res_dft);
459
460 (0..cols_out).for_each(|i| {
461 module.vec_znx_big_normalize(basek, self, i, &res_big, i, scratch1);
462 });
463 }
464
465 pub fn keyswitch<DataLhs, DataRhs>(
466 &mut self,
467 module: &Module<FFT64>,
468 lhs: &GLWECiphertext<DataLhs>,
469 rhs: &GLWESwitchingKey<DataRhs, FFT64>,
470 scratch: &mut Scratch,
471 ) where
472 VecZnx<DataLhs>: VecZnxToRef,
473 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
474 {
475 Self::keyswitch_private::<_, _, 0>(self, 0, module, lhs, rhs, scratch);
476 }
477
478 pub(crate) fn keyswitch_private<DataLhs, DataRhs, const OP: u8>(
479 &mut self,
480 apply_auto: i64,
481 module: &Module<FFT64>,
482 lhs: &GLWECiphertext<DataLhs>,
483 rhs: &GLWESwitchingKey<DataRhs, FFT64>,
484 scratch: &mut Scratch,
485 ) where
486 VecZnx<DataLhs>: VecZnxToRef,
487 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
488 {
489 let basek: usize = self.basek();
490
491 #[cfg(debug_assertions)]
492 {
493 assert_eq!(lhs.rank(), rhs.rank_in());
494 assert_eq!(self.rank(), rhs.rank_out());
495 assert_eq!(self.basek(), basek);
496 assert_eq!(lhs.basek(), basek);
497 assert_eq!(rhs.n(), module.n());
498 assert_eq!(self.n(), module.n());
499 assert_eq!(lhs.n(), module.n());
500 assert!(
501 scratch.available()
502 >= GLWECiphertext::keyswitch_scratch_space(
503 module,
504 self.size(),
505 self.rank(),
506 lhs.size(),
507 lhs.rank(),
508 rhs.size(),
509 )
510 );
511 }
512
513 let cols_in: usize = rhs.rank_in();
514 let cols_out: usize = rhs.rank_out() + 1;
515
516 let (mut res_dft, scratch1) = scratch.tmp_vec_znx_dft(module, cols_out, rhs.size()); // Todo optimise
517
518 {
519 let (mut ai_dft, scratch2) = scratch1.tmp_vec_znx_dft(module, cols_in, lhs.size());
520 (0..cols_in).for_each(|col_i| {
521 module.vec_znx_dft(&mut ai_dft, col_i, lhs, col_i + 1);
522 });
523 module.vmp_apply(&mut res_dft, &ai_dft, rhs, scratch2);
524 }
525
526 let mut res_big: VecZnxBig<&mut [u8], FFT64> = module.vec_znx_idft_consume(res_dft);
527
528 module.vec_znx_big_add_small_inplace(&mut res_big, 0, lhs, 0);
529
530 (0..cols_out).for_each(|i| {
531 if apply_auto != 0 {
532 module.vec_znx_big_automorphism_inplace(apply_auto, &mut res_big, i);
533 }
534
535 match OP {
536 1 => module.vec_znx_big_add_small_inplace(&mut res_big, i, lhs, i),
537 2 => module.vec_znx_big_sub_small_a_inplace(&mut res_big, i, lhs, i),
538 3 => module.vec_znx_big_sub_small_b_inplace(&mut res_big, i, lhs, i),
539 _ => {}
540 }
541 module.vec_znx_big_normalize(basek, self, i, &res_big, i, scratch1);
542 });
543 }
544
545 pub fn keyswitch_inplace<DataRhs>(
546 &mut self,
547 module: &Module<FFT64>,
548 rhs: &GLWESwitchingKey<DataRhs, FFT64>,
549 scratch: &mut Scratch,
550 ) where
551 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
552 {
553 unsafe {
554 let self_ptr: *mut GLWECiphertext<DataSelf> = self as *mut GLWECiphertext<DataSelf>;
555 self.keyswitch(&module, &*self_ptr, rhs, scratch);
556 }
557 }
558
559 pub fn external_product<DataLhs, DataRhs>(
560 &mut self,
561 module: &Module<FFT64>,
562 lhs: &GLWECiphertext<DataLhs>,
563 rhs: &GGSWCiphertext<DataRhs, FFT64>,
564 scratch: &mut Scratch,
565 ) where
566 VecZnx<DataLhs>: VecZnxToRef,
567 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
568 {
569 let basek: usize = self.basek();
570
571 #[cfg(debug_assertions)]
572 {
573 assert_eq!(rhs.rank(), lhs.rank());
574 assert_eq!(rhs.rank(), self.rank());
575 assert_eq!(self.basek(), basek);
576 assert_eq!(lhs.basek(), basek);
577 assert_eq!(rhs.n(), module.n());
578 assert_eq!(self.n(), module.n());
579 assert_eq!(lhs.n(), module.n());
580 }
581
582 let cols: usize = rhs.rank() + 1;
583
584 let (mut res_dft, scratch1) = scratch.tmp_vec_znx_dft(module, cols, rhs.size()); // Todo optimise
585
586 {
587 let (mut a_dft, scratch2) = scratch1.tmp_vec_znx_dft(module, cols, lhs.size());
588 (0..cols).for_each(|col_i| {
589 module.vec_znx_dft(&mut a_dft, col_i, lhs, col_i);
590 });
591 module.vmp_apply(&mut res_dft, &a_dft, rhs, scratch2);
592 }
593
594 let res_big: VecZnxBig<&mut [u8], FFT64> = module.vec_znx_idft_consume(res_dft);
595
596 (0..cols).for_each(|i| {
597 module.vec_znx_big_normalize(basek, self, i, &res_big, i, scratch1);
598 });
599 }
600
601 pub fn external_product_inplace<DataRhs>(
602 &mut self,
603 module: &Module<FFT64>,
604 rhs: &GGSWCiphertext<DataRhs, FFT64>,
605 scratch: &mut Scratch,
606 ) where
607 MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
608 {
609 unsafe {
610 let self_ptr: *mut GLWECiphertext<DataSelf> = self as *mut GLWECiphertext<DataSelf>;
611 self.external_product(&module, &*self_ptr, rhs, scratch);
612 }
613 }
614
615 pub(crate) fn encrypt_sk_private<DataPt, DataSk>(
616 &mut self,
617 module: &Module<FFT64>,
618 pt: Option<(&GLWEPlaintext<DataPt>, usize)>,
619 sk_dft: &SecretKeyFourier<DataSk, FFT64>,
620 source_xa: &mut Source,
621 source_xe: &mut Source,
622 sigma: f64,
623 scratch: &mut Scratch,
624 ) where
625 VecZnx<DataPt>: VecZnxToRef,
626 ScalarZnxDft<DataSk, FFT64>: ScalarZnxDftToRef<FFT64>,
627 {
628 #[cfg(debug_assertions)]
629 {
630 assert_eq!(self.rank(), sk_dft.rank());
631 assert_eq!(sk_dft.n(), module.n());
632 assert_eq!(self.n(), module.n());
633 if let Some((pt, col)) = pt {
634 assert_eq!(pt.n(), module.n());
635 assert!(col < self.rank() + 1);
636 }
637 assert!(
638 scratch.available() >= GLWECiphertext::encrypt_sk_scratch_space(module, self.size()),
639 "scratch.available(): {} < GLWECiphertext::encrypt_sk_scratch_space: {}",
640 scratch.available(),
641 GLWECiphertext::encrypt_sk_scratch_space(module, self.size())
642 )
643 }
644
645 let basek: usize = self.basek();
646 let k: usize = self.k();
647 let size: usize = self.size();
648 let cols: usize = self.rank() + 1;
649
650 let (mut c0_big, scratch_1) = scratch.tmp_vec_znx(module, 1, size);
651 c0_big.zero();
652
653 {
654 // c[i] = uniform
655 // c[0] -= c[i] * s[i],
656 (1..cols).for_each(|i| {
657 let (mut ci_dft, scratch_2) = scratch_1.tmp_vec_znx_dft(module, 1, size);
658
659 // c[i] = uniform
660 self.data.fill_uniform(basek, i, size, source_xa);
661
662 // c[i] = norm(IDFT(DFT(c[i]) * DFT(s[i])))
663 module.vec_znx_dft(&mut ci_dft, 0, self, i);
664 module.svp_apply_inplace(&mut ci_dft, 0, sk_dft, i - 1);
665 let ci_big: VecZnxBig<&mut [u8], FFT64> = module.vec_znx_idft_consume(ci_dft);
666
667 // use c[0] as buffer, which is overwritten later by the normalization step
668 module.vec_znx_big_normalize(basek, self, 0, &ci_big, 0, scratch_2);
669
670 // c0_tmp = -c[i] * s[i] (use c[0] as buffer)
671 module.vec_znx_sub_ab_inplace(&mut c0_big, 0, self, 0);
672
673 // c[i] += m if col = i
674 if let Some((pt, col)) = pt {
675 if i == col {
676 module.vec_znx_add_inplace(self, i, pt, 0);
677 module.vec_znx_normalize_inplace(basek, self, i, scratch_2);
678 }
679 }
680 });
681 }
682
683 // c[0] += e
684 c0_big.add_normal(basek, 0, k, source_xe, sigma, sigma * SIX_SIGMA);
685
686 // c[0] += m if col = 0
687 if let Some((pt, col)) = pt {
688 if col == 0 {
689 module.vec_znx_add_inplace(&mut c0_big, 0, pt, 0);
690 }
691 }
692
693 // c[0] = norm(c[0])
694 module.vec_znx_normalize(basek, self, 0, &c0_big, 0, scratch_1);
695 }
696
697 pub(crate) fn encrypt_pk_private<DataPt, DataPk>(
698 &mut self,
699 module: &Module<FFT64>,
700 pt: Option<(&GLWEPlaintext<DataPt>, usize)>,
701 pk: &GLWEPublicKey<DataPk, FFT64>,
702 source_xu: &mut Source,
703 source_xe: &mut Source,
704 sigma: f64,
705 scratch: &mut Scratch,
706 ) where
707 VecZnx<DataPt>: VecZnxToRef,
708 VecZnxDft<DataPk, FFT64>: VecZnxDftToRef<FFT64>,
709 {
710 #[cfg(debug_assertions)]
711 {
712 assert_eq!(self.basek(), pk.basek());
713 assert_eq!(self.n(), module.n());
714 assert_eq!(pk.n(), module.n());
715 assert_eq!(self.rank(), pk.rank());
716 if let Some((pt, _)) = pt {
717 assert_eq!(pt.basek(), pk.basek());
718 assert_eq!(pt.n(), module.n());
719 }
720 }
721
722 let basek: usize = pk.basek();
723 let size_pk: usize = pk.size();
724 let cols: usize = self.rank() + 1;
725
726 // Generates u according to the underlying secret distribution.
727 let (mut u_dft, scratch_1) = scratch.tmp_scalar_znx_dft(module, 1);
728
729 {
730 let (mut u, _) = scratch_1.tmp_scalar_znx(module, 1);
731 match pk.dist {
732 SecretDistribution::NONE => panic!(
733 "invalid public key: SecretDistribution::NONE, ensure it has been correctly intialized through \
734 Self::generate"
735 ),
736 SecretDistribution::TernaryFixed(hw) => u.fill_ternary_hw(0, hw, source_xu),
737 SecretDistribution::TernaryProb(prob) => u.fill_ternary_prob(0, prob, source_xu),
738 SecretDistribution::ZERO => {}
739 }
740
741 module.svp_prepare(&mut u_dft, 0, &u, 0);
742 }
743
744 // ct[i] = pk[i] * u + ei (+ m if col = i)
745 (0..cols).for_each(|i| {
746 let (mut ci_dft, scratch_2) = scratch_1.tmp_vec_znx_dft(module, 1, size_pk);
747 // ci_dft = DFT(u) * DFT(pk[i])
748 module.svp_apply(&mut ci_dft, 0, &u_dft, 0, pk, i);
749
750 // ci_big = u * p[i]
751 let mut ci_big = module.vec_znx_idft_consume(ci_dft);
752
753 // ci_big = u * pk[i] + e
754 ci_big.add_normal(basek, 0, pk.k(), source_xe, sigma, sigma * SIX_SIGMA);
755
756 // ci_big = u * pk[i] + e + m (if col = i)
757 if let Some((pt, col)) = pt {
758 if col == i {
759 module.vec_znx_big_add_small_inplace(&mut ci_big, 0, pt, 0);
760 }
761 }
762
763 // ct[i] = norm(ci_big)
764 module.vec_znx_big_normalize(basek, self, i, &ci_big, 0, scratch_2);
765 });
766 }
767}
768
769impl<DataSelf> GLWECiphertext<DataSelf>
770where
771 VecZnx<DataSelf>: VecZnxToRef,
772{
773 pub fn clone(&self) -> GLWECiphertext<Vec<u8>> {
774 GLWECiphertext {
775 data: self.data.clone(),
776 basek: self.basek(),
777 k: self.k(),
778 }
779 }
780
781 pub fn decrypt<DataPt, DataSk>(
782 &self,
783 module: &Module<FFT64>,
784 pt: &mut GLWEPlaintext<DataPt>,
785 sk_dft: &SecretKeyFourier<DataSk, FFT64>,
786 scratch: &mut Scratch,
787 ) where
788 VecZnx<DataPt>: VecZnxToMut,
789 ScalarZnxDft<DataSk, FFT64>: ScalarZnxDftToRef<FFT64>,
790 {
791 #[cfg(debug_assertions)]
792 {
793 assert_eq!(self.rank(), sk_dft.rank());
794 assert_eq!(self.n(), module.n());
795 assert_eq!(pt.n(), module.n());
796 assert_eq!(sk_dft.n(), module.n());
797 }
798
799 let cols: usize = self.rank() + 1;
800
801 let (mut c0_big, scratch_1) = scratch.tmp_vec_znx_big(module, 1, self.size()); // TODO optimize size when pt << ct
802 c0_big.zero();
803
804 {
805 (1..cols).for_each(|i| {
806 // ci_dft = DFT(a[i]) * DFT(s[i])
807 let (mut ci_dft, _) = scratch_1.tmp_vec_znx_dft(module, 1, self.size()); // TODO optimize size when pt << ct
808 module.vec_znx_dft(&mut ci_dft, 0, self, i);
809 module.svp_apply_inplace(&mut ci_dft, 0, sk_dft, i - 1);
810 let ci_big = module.vec_znx_idft_consume(ci_dft);
811
812 // c0_big += a[i] * s[i]
813 module.vec_znx_big_add_inplace(&mut c0_big, 0, &ci_big, 0);
814 });
815 }
816
817 // c0_big = (a * s) + (-a * s + m + e) = BIG(m + e)
818 module.vec_znx_big_add_small_inplace(&mut c0_big, 0, self, 0);
819
820 // pt = norm(BIG(m + e))
821 module.vec_znx_big_normalize(self.basek(), pt, 0, &mut c0_big, 0, scratch_1);
822
823 pt.basek = self.basek();
824 pt.k = pt.k().min(self.k());
825 }
826}