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