testudo/src/product_tree.rs
src/product_tree.rsRaw
1#![allow(dead_code)]
2use crate::poseidon_transcript::PoseidonTranscript;
3
4use super::dense_mlpoly::DensePolynomial;
5use super::dense_mlpoly::EqPolynomial;
6use super::math::Math;
7use super::scalar::Scalar;
8use super::sumcheck::SumcheckInstanceProof;
9use ark_serialize::*;
10use ark_std::One;
11
12#[derive(Debug)]
13pub struct ProductCircuit {
14 left_vec: Vec<DensePolynomial>,
15 right_vec: Vec<DensePolynomial>,
16}
17
18impl ProductCircuit {
19 fn compute_layer(
20 inp_left: &DensePolynomial,
21 inp_right: &DensePolynomial,
22 ) -> (DensePolynomial, DensePolynomial) {
23 let len = inp_left.len() + inp_right.len();
24 let outp_left = (0..len / 4)
25 .map(|i| inp_left[i] * inp_right[i])
26 .collect::<Vec<Scalar>>();
27 let outp_right = (len / 4..len / 2)
28 .map(|i| inp_left[i] * inp_right[i])
29 .collect::<Vec<Scalar>>();
30
31 (
32 DensePolynomial::new(outp_left),
33 DensePolynomial::new(outp_right),
34 )
35 }
36
37 pub fn new(poly: &DensePolynomial) -> Self {
38 let mut left_vec: Vec<DensePolynomial> = Vec::new();
39 let mut right_vec: Vec<DensePolynomial> = Vec::new();
40
41 let num_layers = poly.len().log_2();
42 let (outp_left, outp_right) = poly.split(poly.len() / 2);
43
44 left_vec.push(outp_left);
45 right_vec.push(outp_right);
46
47 for i in 0..num_layers - 1 {
48 let (outp_left, outp_right) =
49 ProductCircuit::compute_layer(&left_vec[i], &right_vec[i]);
50 left_vec.push(outp_left);
51 right_vec.push(outp_right);
52 }
53
54 ProductCircuit {
55 left_vec,
56 right_vec,
57 }
58 }
59
60 pub fn evaluate(&self) -> Scalar {
61 let len = self.left_vec.len();
62 assert_eq!(self.left_vec[len - 1].get_num_vars(), 0);
63 assert_eq!(self.right_vec[len - 1].get_num_vars(), 0);
64 self.left_vec[len - 1][0] * self.right_vec[len - 1][0]
65 }
66}
67
68pub struct DotProductCircuit {
69 left: DensePolynomial,
70 right: DensePolynomial,
71 weight: DensePolynomial,
72}
73
74impl DotProductCircuit {
75 pub fn new(left: DensePolynomial, right: DensePolynomial, weight: DensePolynomial) -> Self {
76 assert_eq!(left.len(), right.len());
77 assert_eq!(left.len(), weight.len());
78 DotProductCircuit {
79 left,
80 right,
81 weight,
82 }
83 }
84
85 pub fn evaluate(&self) -> Scalar {
86 (0..self.left.len())
87 .map(|i| self.left[i] * self.right[i] * self.weight[i])
88 .sum()
89 }
90
91 pub fn split(&mut self) -> (DotProductCircuit, DotProductCircuit) {
92 let idx = self.left.len() / 2;
93 assert_eq!(idx * 2, self.left.len());
94 let (l1, l2) = self.left.split(idx);
95 let (r1, r2) = self.right.split(idx);
96 let (w1, w2) = self.weight.split(idx);
97 (
98 DotProductCircuit {
99 left: l1,
100 right: r1,
101 weight: w1,
102 },
103 DotProductCircuit {
104 left: l2,
105 right: r2,
106 weight: w2,
107 },
108 )
109 }
110}
111
112#[allow(dead_code)]
113#[derive(Debug, CanonicalSerialize, CanonicalDeserialize)]
114pub struct LayerProof {
115 pub proof: SumcheckInstanceProof,
116 pub claims: Vec<Scalar>,
117}
118
119#[allow(dead_code)]
120impl LayerProof {
121 pub fn verify(
122 &self,
123 claim: Scalar,
124 num_rounds: usize,
125 degree_bound: usize,
126 transcript: &mut PoseidonTranscript,
127 ) -> (Scalar, Vec<Scalar>) {
128 self.proof
129 .verify(claim, num_rounds, degree_bound, transcript)
130 .unwrap()
131 }
132}
133
134#[allow(dead_code)]
135#[derive(Debug, CanonicalSerialize, CanonicalDeserialize)]
136pub struct LayerProofBatched {
137 pub proof: SumcheckInstanceProof,
138 pub claims_prod_left: Vec<Scalar>,
139 pub claims_prod_right: Vec<Scalar>,
140}
141
142#[allow(dead_code)]
143impl LayerProofBatched {
144 pub fn verify(
145 &self,
146 claim: Scalar,
147 num_rounds: usize,
148 degree_bound: usize,
149 transcript: &mut PoseidonTranscript,
150 ) -> (Scalar, Vec<Scalar>) {
151 self.proof
152 .verify(claim, num_rounds, degree_bound, transcript)
153 .unwrap()
154 }
155}
156
157#[derive(Debug, CanonicalSerialize, CanonicalDeserialize)]
158pub struct ProductCircuitEvalProof {
159 proof: Vec<LayerProof>,
160}
161
162#[derive(Debug, CanonicalSerialize, CanonicalDeserialize)]
163pub struct ProductCircuitEvalProofBatched {
164 proof: Vec<LayerProofBatched>,
165 claims_dotp: (Vec<Scalar>, Vec<Scalar>, Vec<Scalar>),
166}
167
168impl ProductCircuitEvalProof {
169 #![allow(dead_code)]
170 pub fn prove(
171 circuit: &mut ProductCircuit,
172 transcript: &mut PoseidonTranscript,
173 ) -> (Self, Scalar, Vec<Scalar>) {
174 let mut proof: Vec<LayerProof> = Vec::new();
175 let num_layers = circuit.left_vec.len();
176
177 let mut claim = circuit.evaluate();
178 let mut rand = Vec::new();
179 for layer_id in (0..num_layers).rev() {
180 let len = circuit.left_vec[layer_id].len() + circuit.right_vec[layer_id].len();
181
182 let mut poly_C = DensePolynomial::new(EqPolynomial::new(rand.clone()).evals());
183 assert_eq!(poly_C.len(), len / 2);
184
185 let num_rounds_prod = poly_C.len().log_2();
186 let comb_func_prod =
187 |poly_A_comp: &Scalar, poly_B_comp: &Scalar, poly_C_comp: &Scalar| -> Scalar {
188 (*poly_A_comp) * poly_B_comp * poly_C_comp
189 };
190 let (proof_prod, rand_prod, claims_prod) = SumcheckInstanceProof::prove_cubic(
191 &claim,
192 num_rounds_prod,
193 &mut circuit.left_vec[layer_id],
194 &mut circuit.right_vec[layer_id],
195 &mut poly_C,
196 comb_func_prod,
197 transcript,
198 );
199
200 transcript.append_scalar(&claims_prod[0]);
201 transcript.append_scalar(&claims_prod[1]);
202
203 // produce a random challenge
204 let r_layer = transcript.challenge_scalar();
205 claim = claims_prod[0] + r_layer * (claims_prod[1] - claims_prod[0]);
206
207 let mut ext = vec![r_layer];
208 ext.extend(rand_prod);
209 rand = ext;
210
211 proof.push(LayerProof {
212 proof: proof_prod,
213 claims: claims_prod[0..claims_prod.len() - 1].to_vec(),
214 });
215 }
216
217 (ProductCircuitEvalProof { proof }, claim, rand)
218 }
219
220 pub fn verify(
221 &self,
222 eval: Scalar,
223 len: usize,
224 transcript: &mut PoseidonTranscript,
225 ) -> (Scalar, Vec<Scalar>) {
226 let num_layers = len.log_2();
227 let mut claim = eval;
228 let mut rand: Vec<Scalar> = Vec::new();
229 //let mut num_rounds = 0;
230 assert_eq!(self.proof.len(), num_layers);
231 for (num_rounds, i) in (0..num_layers).enumerate() {
232 let (claim_last, rand_prod) = self.proof[i].verify(claim, num_rounds, 3, transcript);
233
234 let claims_prod = &self.proof[i].claims;
235 transcript.append_scalar(&claims_prod[0]);
236 transcript.append_scalar(&claims_prod[1]);
237
238 assert_eq!(rand.len(), rand_prod.len());
239 let eq: Scalar = (0..rand.len())
240 .map(|i| {
241 rand[i] * rand_prod[i]
242 + (Scalar::one() - rand[i]) * (Scalar::one() - rand_prod[i])
243 })
244 .product();
245 assert_eq!(claims_prod[0] * claims_prod[1] * eq, claim_last);
246
247 // produce a random challenge
248 let r_layer = transcript.challenge_scalar();
249 claim = (Scalar::one() - r_layer) * claims_prod[0] + r_layer * claims_prod[1];
250 let mut ext = vec![r_layer];
251 ext.extend(rand_prod);
252 rand = ext;
253 }
254
255 (claim, rand)
256 }
257}
258
259impl ProductCircuitEvalProofBatched {
260 pub fn prove(
261 prod_circuit_vec: &mut Vec<&mut ProductCircuit>,
262 dotp_circuit_vec: &mut Vec<&mut DotProductCircuit>,
263 transcript: &mut PoseidonTranscript,
264 ) -> (Self, Vec<Scalar>) {
265 assert!(!prod_circuit_vec.is_empty());
266
267 let mut claims_dotp_final = (Vec::new(), Vec::new(), Vec::new());
268
269 let mut proof_layers: Vec<LayerProofBatched> = Vec::new();
270 let num_layers = prod_circuit_vec[0].left_vec.len();
271 let mut claims_to_verify = (0..prod_circuit_vec.len())
272 .map(|i| prod_circuit_vec[i].evaluate())
273 .collect::<Vec<Scalar>>();
274 let mut rand = Vec::new();
275 for layer_id in (0..num_layers).rev() {
276 // prepare paralell instance that share poly_C first
277 let len = prod_circuit_vec[0].left_vec[layer_id].len()
278 + prod_circuit_vec[0].right_vec[layer_id].len();
279
280 let mut poly_C_par = DensePolynomial::new(EqPolynomial::new(rand.clone()).evals());
281 assert_eq!(poly_C_par.len(), len / 2);
282
283 let num_rounds_prod = poly_C_par.len().log_2();
284 let comb_func_prod =
285 |poly_A_comp: &Scalar, poly_B_comp: &Scalar, poly_C_comp: &Scalar| -> Scalar {
286 (*poly_A_comp) * poly_B_comp * poly_C_comp
287 };
288
289 let mut poly_A_batched_par: Vec<&mut DensePolynomial> = Vec::new();
290 let mut poly_B_batched_par: Vec<&mut DensePolynomial> = Vec::new();
291 for prod_circuit in prod_circuit_vec.iter_mut() {
292 poly_A_batched_par.push(&mut prod_circuit.left_vec[layer_id]);
293 poly_B_batched_par.push(&mut prod_circuit.right_vec[layer_id])
294 }
295 let poly_vec_par = (
296 &mut poly_A_batched_par,
297 &mut poly_B_batched_par,
298 &mut poly_C_par,
299 );
300
301 // prepare sequential instances that don't share poly_C
302 let mut poly_A_batched_seq: Vec<&mut DensePolynomial> = Vec::new();
303 let mut poly_B_batched_seq: Vec<&mut DensePolynomial> = Vec::new();
304 let mut poly_C_batched_seq: Vec<&mut DensePolynomial> = Vec::new();
305 if layer_id == 0 && !dotp_circuit_vec.is_empty() {
306 // add additional claims
307 for item in dotp_circuit_vec.iter() {
308 claims_to_verify.push(item.evaluate());
309 assert_eq!(len / 2, item.left.len());
310 assert_eq!(len / 2, item.right.len());
311 assert_eq!(len / 2, item.weight.len());
312 }
313
314 for dotp_circuit in dotp_circuit_vec.iter_mut() {
315 poly_A_batched_seq.push(&mut dotp_circuit.left);
316 poly_B_batched_seq.push(&mut dotp_circuit.right);
317 poly_C_batched_seq.push(&mut dotp_circuit.weight);
318 }
319 }
320 let poly_vec_seq = (
321 &mut poly_A_batched_seq,
322 &mut poly_B_batched_seq,
323 &mut poly_C_batched_seq,
324 );
325
326 // produce a fresh set of coeffs and a joint claim
327 let coeff_vec = transcript.challenge_vector(claims_to_verify.len());
328 let claim = (0..claims_to_verify.len())
329 .map(|i| claims_to_verify[i] * coeff_vec[i])
330 .sum();
331
332 let (proof, rand_prod, claims_prod, claims_dotp) =
333 SumcheckInstanceProof::prove_cubic_batched(
334 &claim,
335 num_rounds_prod,
336 poly_vec_par,
337 poly_vec_seq,
338 &coeff_vec,
339 comb_func_prod,
340 transcript,
341 );
342
343 let (claims_prod_left, claims_prod_right, _claims_eq) = claims_prod;
344 for i in 0..prod_circuit_vec.len() {
345 transcript.append_scalar(&claims_prod_left[i]);
346 transcript.append_scalar(&claims_prod_right[i]);
347 }
348
349 if layer_id == 0 && !dotp_circuit_vec.is_empty() {
350 let (claims_dotp_left, claims_dotp_right, claims_dotp_weight) = claims_dotp;
351 for i in 0..dotp_circuit_vec.len() {
352 transcript.append_scalar(&claims_dotp_left[i]);
353 transcript.append_scalar(&claims_dotp_right[i]);
354 transcript.append_scalar(&claims_dotp_weight[i]);
355 }
356 claims_dotp_final = (claims_dotp_left, claims_dotp_right, claims_dotp_weight);
357 }
358
359 // produce a random challenge to condense two claims into a single claim
360 let r_layer = transcript.challenge_scalar();
361
362 claims_to_verify = (0..prod_circuit_vec.len())
363 .map(|i| {
364 claims_prod_left[i] + r_layer * (claims_prod_right[i] - claims_prod_left[i])
365 })
366 .collect::<Vec<Scalar>>();
367
368 let mut ext = vec![r_layer];
369 ext.extend(rand_prod);
370 rand = ext;
371
372 proof_layers.push(LayerProofBatched {
373 proof,
374 claims_prod_left,
375 claims_prod_right,
376 });
377 }
378
379 (
380 ProductCircuitEvalProofBatched {
381 proof: proof_layers,
382 claims_dotp: claims_dotp_final,
383 },
384 rand,
385 )
386 }
387
388 pub fn verify(
389 &self,
390 claims_prod_vec: &[Scalar],
391 claims_dotp_vec: &[Scalar],
392 len: usize,
393 transcript: &mut PoseidonTranscript,
394 ) -> (Vec<Scalar>, Vec<Scalar>, Vec<Scalar>) {
395 let num_layers = len.log_2();
396 let mut rand: Vec<Scalar> = Vec::new();
397 //let mut num_rounds = 0;
398 assert_eq!(self.proof.len(), num_layers);
399
400 let mut claims_to_verify = claims_prod_vec.to_owned();
401 let mut claims_to_verify_dotp: Vec<Scalar> = Vec::new();
402 for (num_rounds, i) in (0..num_layers).enumerate() {
403 if i == num_layers - 1 {
404 claims_to_verify.extend(claims_dotp_vec);
405 }
406
407 // produce random coefficients, one for each instance
408 let coeff_vec = transcript.challenge_vector(claims_to_verify.len());
409
410 // produce a joint claim
411 let claim = (0..claims_to_verify.len())
412 .map(|i| claims_to_verify[i] * coeff_vec[i])
413 .sum();
414
415 let (claim_last, rand_prod) = self.proof[i].verify(claim, num_rounds, 3, transcript);
416
417 let claims_prod_left = &self.proof[i].claims_prod_left;
418 let claims_prod_right = &self.proof[i].claims_prod_right;
419 assert_eq!(claims_prod_left.len(), claims_prod_vec.len());
420 assert_eq!(claims_prod_right.len(), claims_prod_vec.len());
421
422 for i in 0..claims_prod_vec.len() {
423 transcript.append_scalar(&claims_prod_left[i]);
424 transcript.append_scalar(&claims_prod_right[i]);
425 }
426
427 assert_eq!(rand.len(), rand_prod.len());
428 let eq: Scalar = (0..rand.len())
429 .map(|i| {
430 rand[i] * rand_prod[i]
431 + (Scalar::one() - rand[i]) * (Scalar::one() - rand_prod[i])
432 })
433 .product();
434 let mut claim_expected: Scalar = (0..claims_prod_vec.len())
435 .map(|i| coeff_vec[i] * (claims_prod_left[i] * claims_prod_right[i] * eq))
436 .sum();
437
438 // add claims from the dotp instances
439 if i == num_layers - 1 {
440 let num_prod_instances = claims_prod_vec.len();
441 let (claims_dotp_left, claims_dotp_right, claims_dotp_weight) = &self.claims_dotp;
442 for i in 0..claims_dotp_left.len() {
443 transcript.append_scalar(&claims_dotp_left[i]);
444 transcript.append_scalar(&claims_dotp_right[i]);
445 transcript.append_scalar(&claims_dotp_weight[i]);
446
447 claim_expected += coeff_vec[i + num_prod_instances]
448 * claims_dotp_left[i]
449 * claims_dotp_right[i]
450 * claims_dotp_weight[i];
451 }
452 }
453
454 assert_eq!(claim_expected, claim_last);
455
456 // produce a random challenge
457 let r_layer = transcript.challenge_scalar();
458
459 claims_to_verify = (0..claims_prod_left.len())
460 .map(|i| {
461 claims_prod_left[i] + r_layer * (claims_prod_right[i] - claims_prod_left[i])
462 })
463 .collect();
464
465 // add claims to verify for dotp circuit
466 if i == num_layers - 1 {
467 let (claims_dotp_left, claims_dotp_right, claims_dotp_weight) = &self.claims_dotp;
468
469 for i in 0..claims_dotp_vec.len() / 2 {
470 // combine left claims
471 let claim_left = claims_dotp_left[2 * i]
472 + r_layer * (claims_dotp_left[2 * i + 1] - claims_dotp_left[2 * i]);
473
474 let claim_right = claims_dotp_right[2 * i]
475 + r_layer * (claims_dotp_right[2 * i + 1] - claims_dotp_right[2 * i]);
476
477 let claim_weight = claims_dotp_weight[2 * i]
478 + r_layer * (claims_dotp_weight[2 * i + 1] - claims_dotp_weight[2 * i]);
479 claims_to_verify_dotp.push(claim_left);
480 claims_to_verify_dotp.push(claim_right);
481 claims_to_verify_dotp.push(claim_weight);
482 }
483 }
484
485 let mut ext = vec![r_layer];
486 ext.extend(rand_prod);
487 rand = ext;
488 }
489 (claims_to_verify, claims_to_verify_dotp, rand)
490 }
491}