Git-Mirrors/monero
1
0
Fork 0
mirror of https://github.com/monero-project/monero.git synced 2025-08-02 18:16:07 -04:00
Code Issues Projects Releases Packages Wiki Activity

bulletproofs: speed up the latest changes a bit

Browse source
This commit is contained in:
moneromooo-monero 2018-08-06 15:21:07 +00:00
parent 044dff5a30
commit 2bf636503f
No known key found for this signature in database
GPG key ID: 686F07454D6CEFC3
7 changed files with 68 additions and 35 deletions
Download patch file Download diff file Expand all files Collapse all files

70
src/ringct/bulletproofs.cc
View file

@ -92,21 +92,6 @@ static bool is_reduced(const rct::key &scalar)
return scalar == reduced;
}
//addKeys3acc_p3
//aAbB += a*A + b*B where a, b are scalars, A, B are curve points
//A and B must be input after applying "precomp"
static void addKeys3acc_p3(ge_p3 *aAbB, const key &a, const ge_dsmp A, const key &b, const ge_dsmp B)
{
ge_p3 rv;
ge_p1p1 p1;
ge_p2 p2;
ge_double_scalarmult_precomp_vartime2_p3(&rv, a.bytes, A, b.bytes, B);
ge_cached cached;
ge_p3_to_cached(&cached, aAbB);
ge_add(&p1, &rv, &cached);
ge_p1p1_to_p3(aAbB, &p1);
}
static void addKeys_acc_p3(ge_p3 *acc_p3, const rct::key &a, const rct::key &point)
{
ge_p3 p3;
@ -119,6 +104,28 @@ static void addKeys_acc_p3(ge_p3 *acc_p3, const rct::key &a, const rct::key &poi
ge_p1p1_to_p3(acc_p3, &p1);
}
static void add_acc_p3(ge_p3 *acc_p3, const rct::key &point)
{
ge_p3 p3;
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&p3, point.bytes) == 0, "ge_frombytes_vartime failed");
ge_cached cached;
ge_p3_to_cached(&cached, &p3);
ge_p1p1 p1;
ge_add(&p1, acc_p3, &cached);
ge_p1p1_to_p3(acc_p3, &p1);
}
static void sub_acc_p3(ge_p3 *acc_p3, const rct::key &point)
{
ge_p3 p3;
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&p3, point.bytes) == 0, "ge_frombytes_vartime failed");
ge_cached cached;
ge_p3_to_cached(&cached, &p3);
ge_p1p1 p1;
ge_sub(&p1, acc_p3, &cached);
ge_p1p1_to_p3(acc_p3, &p1);
}
static rct::key scalarmultKey(const ge_p3 &P, const rct::key &a)
{
ge_p2 R;
@ -1087,9 +1094,7 @@ bool bulletproof_VERIFY(const std::vector<const Bulletproof*> &proofs)
sc_mul(tmp.bytes, zpow[j+2].bytes, EIGHT.bytes);
multiexp_data.emplace_back(tmp, proof.V[j]);
}
rct::key temp = multiexp(multiexp_data, false);
rct::addKeys(Y2, Y2, rct::scalarmultKey(temp, weight));
rct::addKeys(Y2, Y2, rct::scalarmultKey(multiexp(multiexp_data, false), weight));
rct::key weight8;
sc_mul(weight8.bytes, weight.bytes, EIGHT.bytes);
sc_mul(tmp.bytes, x.bytes, weight8.bytes);
@ -1103,7 +1108,7 @@ bool bulletproof_VERIFY(const std::vector<const Bulletproof*> &proofs)
PERF_TIMER_START_BP(VERIFY_line_62);
// PAPER LINE 62
sc_mul(tmp.bytes, x.bytes, EIGHT.bytes);
rct::addKeys(Z0, Z0, rct::scalarmultKey(rct::addKeys(rct::scalarmultKey(proof.A, EIGHT), rct::scalarmultKey(proof.S, tmp)), weight));
rct::addKeys(Z0, Z0, rct::scalarmultKey(rct::addKeys(rct::scalarmult8(proof.A), rct::scalarmultKey(proof.S, tmp)), weight));
PERF_TIMER_STOP(VERIFY_line_62);
// Compute the number of rounds for the inner product
@ -1202,23 +1207,22 @@ bool bulletproof_VERIFY(const std::vector<const Bulletproof*> &proofs)
// now check all proofs at once
PERF_TIMER_START_BP(VERIFY_step2_check);
rct::key check1 = rct::identity();
rct::addKeys(check1, check1, rct::scalarmultBase(y0));
rct::addKeys(check1, check1, rct::scalarmultH(y1));
rct::subKeys(check1, check1, Y2);
rct::subKeys(check1, check1, Y3);
rct::subKeys(check1, check1, Y4);
if (!(check1 == rct::identity()))
ge_p3 check1;
ge_scalarmult_base(&check1, y0.bytes);
addKeys_acc_p3(&check1, y1, rct::H);
sub_acc_p3(&check1, Y2);
sub_acc_p3(&check1, Y3);
sub_acc_p3(&check1, Y4);
if (!ge_p3_is_point_at_infinity(&check1))
{
MERROR("Verification failure at step 1");
return false;
}
rct::key check2 = rct::identity();
rct::addKeys(check2, check2, Z0);
ge_p3 check2;
sc_sub(tmp.bytes, rct::zero().bytes, z1.bytes);
rct::addKeys(check2, check2, rct::scalarmultBase(tmp));
rct::addKeys(check2, check2, Z2);
rct::addKeys(check2, check2, rct::scalarmultH(z3));
ge_double_scalarmult_base_vartime_p3(&check2, z3.bytes, &ge_p3_H, tmp.bytes);
add_acc_p3(&check2, Z0);
add_acc_p3(&check2, Z2);
std::vector<MultiexpData> multiexp_data;
multiexp_data.reserve(2 * maxMN);
@ -1229,10 +1233,10 @@ bool bulletproof_VERIFY(const std::vector<const Bulletproof*> &proofs)
sc_sub(tmp.bytes, rct::zero().bytes, z5[i].bytes);
multiexp_data.emplace_back(tmp, Hi_p3[i]);
}
rct::addKeys(check2, check2, multiexp(multiexp_data, true));
add_acc_p3(&check2, multiexp(multiexp_data, true));
PERF_TIMER_STOP(VERIFY_step2_check);
if (!(check2 == rct::identity()))
if (!ge_p3_is_point_at_infinity(&check2))
{
MERROR("Verification failure at step 2");
return false;

14
src/ringct/rctOps.cpp
View file

@ -211,6 +211,20 @@ namespace rct {
return aP;
}
//Computes 8P
key scalarmult8(const key & P) {
ge_p3 p3;
CHECK_AND_ASSERT_THROW_MES_L1(ge_frombytes_vartime(&p3, P.bytes) == 0, "ge_frombytes_vartime failed at "+boost::lexical_cast<std::string>(__LINE__));
ge_p2 p2;
ge_p3_to_p2(&p2, &p3);
ge_p1p1 p1;
ge_mul8(&p1, &p2);
ge_p1p1_to_p2(&p2, &p1);
rct::key res;
ge_tobytes(res.bytes, &p2);
return res;
}
//Computes aL where L is the curve order
bool isInMainSubgroup(const key & a) {
ge_p3 p3;

2
src/ringct/rctOps.h
View file

@ -122,6 +122,8 @@ namespace rct {
key scalarmultKey(const key &P, const key &a);
//Computes aH where H= toPoint(cn_fast_hash(G)), G the basepoint
key scalarmultH(const key & a);
// multiplies a point by 8
key scalarmult8(const key & P);
// checks a is in the main subgroup (ie, not a small one)
bool isInMainSubgroup(const key & a);

4
src/ringct/rctSigs.cpp
View file

@ -768,7 +768,7 @@ namespace rct {
#endif
for (i = 0; i < outamounts.size(); ++i)
{
rv.outPk[i].mask = rct::scalarmultKey(C[i], EIGHT);
rv.outPk[i].mask = rct::scalarmult8(C[i]);
outSk[i].mask = masks[i];
}
}
@ -788,7 +788,7 @@ namespace rct {
#endif
for (i = 0; i < batch_size; ++i)
{
rv.outPk[i + amounts_proved].mask = rct::scalarmultKey(C[i], EIGHT);
rv.outPk[i + amounts_proved].mask = rct::scalarmult8(C[i]);
outSk[i + amounts_proved].mask = masks[i];
}
amounts_proved += batch_size;