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ringct: add bos coster multiexp

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moneromooo-monero 2018-01-09 13:51:17 +00:00
parent e9164bb38b
commit 9ff6e6a0a7
No known key found for this signature in database
GPG Key ID: 686F07454D6CEFC3
4 changed files with 460 additions and 56 deletions
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2
src/ringct/CMakeLists.txt
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@ -30,11 +30,13 @@ set(ringct_basic_sources
rctOps.cpp
rctTypes.cpp
rctCryptoOps.c
multiexp.cc
bulletproofs.cc)
set(ringct_basic_private_headers
rctOps.h
rctTypes.h
multiexp.h
bulletproofs.h)
monero_private_headers(ringct_basic

215
src/ringct/bulletproofs.cc
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@ -38,6 +38,7 @@ extern "C"
#include "crypto/crypto-ops.h"
}
#include "rctOps.h"
#include "multiexp.h"
#include "bulletproofs.h"
#undef MONERO_DEFAULT_LOG_CATEGORY
@ -58,6 +59,7 @@ static rct::key inner_product(const rct::keyV &a, const rct::keyV &b);
static constexpr size_t maxN = 64;
static constexpr size_t maxM = 16;
static rct::key Hi[maxN*maxM], Gi[maxN*maxM];
static ge_p3 Hi_p3[maxN*maxM], Gi_p3[maxN*maxM];
static ge_dsmp Gprecomp[maxN*maxM], Hprecomp[maxN*maxM];
static const rct::key TWO = { {0x02, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 } };
static const rct::keyV oneN = vector_dup(rct::identity(), maxN);
@ -110,9 +112,12 @@ static void init_exponents()
{
Hi[i] = get_exponent(rct::H, i * 2);
rct::precomp(Hprecomp[i], Hi[i]);
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&Hi_p3[i], Hi[i].bytes) == 0, "ge_frombytes_vartime failed");
Gi[i] = get_exponent(rct::H, i * 2 + 1);
rct::precomp(Gprecomp[i], Gi[i]);
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&Gi_p3[i], Gi[i].bytes) == 0, "ge_frombytes_vartime failed");
}
MINFO("cache size: " << (sizeof(Hi)+sizeof(Hprecomp)+sizeof(Hi_p3))*2/1024 << " kB");
init_done = true;
}
@ -121,6 +126,26 @@ static rct::key vector_exponent(const rct::keyV &a, const rct::keyV &b)
{
CHECK_AND_ASSERT_THROW_MES(a.size() == b.size(), "Incompatible sizes of a and b");
CHECK_AND_ASSERT_THROW_MES(a.size() <= maxN*maxM, "Incompatible sizes of a and maxN");
#if 1
std::vector<MultiexpData> multiexp_data;
multiexp_data.reserve(a.size()*2);
for (size_t i = 0; i < a.size(); ++i)
{
if (!(a[i] == rct::zero()))
{
multiexp_data.resize(multiexp_data.size() + 1);
multiexp_data.back().scalar = a[i];
multiexp_data.back().point = Gi_p3[i];
}
if (!(b[i] == rct::zero()))
{
multiexp_data.resize(multiexp_data.size() + 1);
multiexp_data.back().scalar = b[i];
multiexp_data.back().point = Hi_p3[i];
}
}
return bos_coster_heap_conv_robust(multiexp_data);
#else
ge_p3 res_p3 = ge_p3_identity;
for (size_t i = 0; i < a.size(); ++i)
{
@ -129,6 +154,7 @@ static rct::key vector_exponent(const rct::keyV &a, const rct::keyV &b)
rct::key res;
ge_p3_tobytes(res.bytes, &res_p3);
return res;
#endif
}
/* Compute a custom vector-scalar commitment */
@ -138,6 +164,26 @@ static rct::key vector_exponent_custom(const rct::keyV &A, const rct::keyV &B, c
CHECK_AND_ASSERT_THROW_MES(a.size() == b.size(), "Incompatible sizes of a and b");
CHECK_AND_ASSERT_THROW_MES(a.size() == A.size(), "Incompatible sizes of a and A");
CHECK_AND_ASSERT_THROW_MES(a.size() <= maxN*maxM, "Incompatible sizes of a and maxN");
#if 1
std::vector<MultiexpData> multiexp_data;
multiexp_data.reserve(a.size()*2);
for (size_t i = 0; i < a.size(); ++i)
{
if (!(a[i] == rct::zero()))
{
multiexp_data.resize(multiexp_data.size() + 1);
multiexp_data.back().scalar = a[i];
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&multiexp_data.back().point, A[i].bytes) == 0, "ge_frombytes_vartime failed");
}
if (!(b[i] == rct::zero()))
{
multiexp_data.resize(multiexp_data.size() + 1);
multiexp_data.back().scalar = b[i];
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&multiexp_data.back().point, B[i].bytes) == 0, "ge_frombytes_vartime failed");
}
}
return bos_coster_heap_conv_robust(multiexp_data);
#else
ge_p3 res_p3 = ge_p3_identity;
for (size_t i = 0; i < a.size(); ++i)
{
@ -174,6 +220,7 @@ static rct::key vector_exponent_custom(const rct::keyV &A, const rct::keyV &B, c
rct::key res;
ge_p3_tobytes(res.bytes, &res_p3);
return res;
#endif
}
/* Given a scalar, construct a vector of powers */
@ -924,7 +971,7 @@ bool bulletproof_VERIFY(const Bulletproof &proof)
PERF_TIMER_START_BP(VERIFY_line_61);
// PAPER LINE 61
rct::key L61Left;
rct::key L61Left, L61Right;
rct::addKeys2(L61Left, proof.taux, proof.t, rct::H);
const rct::keyV zpow = vector_powers(z, M+3);
@ -939,37 +986,62 @@ bool bulletproof_VERIFY(const Bulletproof &proof)
}
PERF_TIMER_STOP(VERIFY_line_61);
PERF_TIMER_START_BP(VERIFY_line_61rl);
sc_muladd(tmp.bytes, z.bytes, ip1y.bytes, k.bytes);
rct::key L61Right = rct::scalarmultKey(rct::H, tmp);
ge_p3 L61Right_p3;
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&L61Right_p3, L61Right.bytes) == 0, "ge_frombytes_vartime failed");
for (size_t j = 0; j+1 < proof.V.size(); j += 2)
// multiexp is slower for small numbers of calcs
if (M >= 16)
{
CHECK_AND_ASSERT_MES(j+2+1 < zpow.size(), false, "invalid zpow index");
ge_dsmp precomp0, precomp1;
rct::precomp(precomp0, j < proof.V.size() ? proof.V[j] : rct::identity());
rct::precomp(precomp1, j+1 < proof.V.size() ? proof.V[j+1] : rct::identity());
rct::addKeys3acc_p3(&L61Right_p3, zpow[j+2], precomp0, zpow[j+2+1], precomp1);
PERF_TIMER_START_BP(VERIFY_line_61rl_new);
sc_muladd(tmp.bytes, z.bytes, ip1y.bytes, k.bytes);
std::vector<MultiexpData> multiexp_data;
multiexp_data.reserve(3+M);
multiexp_data.push_back({tmp, rct::H});
for (size_t j = 0; j < M; j++)
{
if (!(zpow[j+2] == rct::zero()))
multiexp_data.push_back({zpow[j+2], j < proof.V.size() ? proof.V[j] : rct::identity()});
}
if (!(x == rct::zero()))
multiexp_data.push_back({x, proof.T1});
rct::key xsq;
sc_mul(xsq.bytes, x.bytes, x.bytes);
if (!(xsq == rct::zero()))
multiexp_data.push_back({xsq, proof.T2});
L61Right = bos_coster_heap_conv_robust(multiexp_data);
PERF_TIMER_STOP(VERIFY_line_61rl_new);
}
for (size_t j = proof.V.size() & 0xfffffffe; j < M; j++)
else
{
CHECK_AND_ASSERT_MES(j+2 < zpow.size(), false, "invalid zpow index");
// faster equivalent to:
// tmp = rct::scalarmultKey(j < proof.V.size() ? proof.V[j] : rct::identity(), zpow[j+2]);
// rct::addKeys(L61Right, L61Right, tmp);
if (j < proof.V.size())
addKeys_acc_p3(&L61Right_p3, zpow[j+2], proof.V[j]);
PERF_TIMER_START_BP(VERIFY_line_61rl_old);
sc_muladd(tmp.bytes, z.bytes, ip1y.bytes, k.bytes);
L61Right = rct::scalarmultKey(rct::H, tmp);
ge_p3 L61Right_p3;
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&L61Right_p3, L61Right.bytes) == 0, "ge_frombytes_vartime failed");
for (size_t j = 0; j+1 < proof.V.size(); j += 2)
{
CHECK_AND_ASSERT_MES(j+2+1 < zpow.size(), false, "invalid zpow index");
ge_dsmp precomp0, precomp1;
rct::precomp(precomp0, j < proof.V.size() ? proof.V[j] : rct::identity());
rct::precomp(precomp1, j+1 < proof.V.size() ? proof.V[j+1] : rct::identity());
rct::addKeys3acc_p3(&L61Right_p3, zpow[j+2], precomp0, zpow[j+2+1], precomp1);
}
for (size_t j = proof.V.size() & 0xfffffffe; j < M; j++)
{
CHECK_AND_ASSERT_MES(j+2 < zpow.size(), false, "invalid zpow index");
// faster equivalent to:
// tmp = rct::scalarmultKey(j < proof.V.size() ? proof.V[j] : rct::identity(), zpow[j+2]);
// rct::addKeys(L61Right, L61Right, tmp);
if (j < proof.V.size())
addKeys_acc_p3(&L61Right_p3, zpow[j+2], proof.V[j]);
}
addKeys_acc_p3(&L61Right_p3, x, proof.T1);
rct::key xsq;
sc_mul(xsq.bytes, x.bytes, x.bytes);
addKeys_acc_p3(&L61Right_p3, xsq, proof.T2);
ge_p3_tobytes(L61Right.bytes, &L61Right_p3);
PERF_TIMER_STOP(VERIFY_line_61rl_old);
}
addKeys_acc_p3(&L61Right_p3, x, proof.T1);
rct::key xsq;
sc_mul(xsq.bytes, x.bytes, x.bytes);
addKeys_acc_p3(&L61Right_p3, xsq, proof.T2);
ge_p3_tobytes(L61Right.bytes, &L61Right_p3);
PERF_TIMER_STOP(VERIFY_line_61rl);
if (!(L61Right == L61Left))
{
MERROR("Verification failure at step 1");
@ -998,7 +1070,6 @@ bool bulletproof_VERIFY(const Bulletproof &proof)
PERF_TIMER_START_BP(VERIFY_line_24_25);
// Basically PAPER LINES 24-25
// Compute the curvepoints from G[i] and H[i]
ge_p3 inner_prod_p3 = ge_p3_identity;
rct::key yinvpow = rct::identity();
rct::key ypow = rct::identity();
@ -1009,6 +1080,9 @@ bool bulletproof_VERIFY(const Bulletproof &proof)
winv[i] = invert(w[i]);
PERF_TIMER_STOP(VERIFY_line_24_25_invert);
std::vector<MultiexpData> multiexp_data;
multiexp_data.clear();
multiexp_data.reserve(MN*2);
for (size_t i = 0; i < MN; ++i)
{
// Convert the index to binary IN REVERSE and construct the scalar exponent
@ -1040,9 +1114,10 @@ bool bulletproof_VERIFY(const Bulletproof &proof)
sc_muladd(tmp.bytes, z.bytes, ypow.bytes, tmp.bytes);
sc_mulsub(h_scalar.bytes, tmp.bytes, yinvpow.bytes, h_scalar.bytes);
// Now compute the basepoint's scalar multiplication
// Each of these could be written as a multiexp operation instead
addKeys3acc_p3(&inner_prod_p3, g_scalar, Gprecomp[i], h_scalar, Hprecomp[i]);
if (!(g_scalar == rct::zero()))
multiexp_data.push_back({g_scalar, Gi_p3[i]});
if (!(h_scalar == rct::zero()))
multiexp_data.push_back({h_scalar, Hi_p3[i]});
if (i != MN-1)
{
@ -1050,36 +1125,64 @@ bool bulletproof_VERIFY(const Bulletproof &proof)
sc_mul(ypow.bytes, ypow.bytes, y.bytes);
}
}
rct::key inner_prod;
ge_p3_tobytes(inner_prod.bytes, &inner_prod_p3);
rct::key inner_prod = bos_coster_heap_conv_robust(multiexp_data);
PERF_TIMER_STOP(VERIFY_line_24_25);
PERF_TIMER_START_BP(VERIFY_line_26);
// PAPER LINE 26
rct::key pprime;
sc_sub(tmp.bytes, rct::zero().bytes, proof.mu.bytes);
rct::addKeys(pprime, P, rct::scalarmultBase(tmp));
ge_p3 pprime_p3;
CHECK_AND_ASSERT_MES(ge_frombytes_vartime(&pprime_p3, pprime.bytes) == 0, false, "ge_frombytes_vartime failed");
for (size_t i = 0; i < rounds; ++i)
// multiexp does not seem to give any speedup here
if(0)
{
sc_mul(tmp.bytes, w[i].bytes, w[i].bytes);
sc_mul(tmp2.bytes, winv[i].bytes, winv[i].bytes);
#if 1
ge_dsmp cacheL, cacheR;
rct::precomp(cacheL, proof.L[i]);
rct::precomp(cacheR, proof.R[i]);
addKeys3acc_p3(&pprime_p3, tmp, cacheL, tmp2, cacheR);
#else
rct::addKeys(pprime, pprime, rct::scalarmultKey(proof.L[i], tmp));
rct::addKeys(pprime, pprime, rct::scalarmultKey(proof.R[i], tmp2));
#endif
PERF_TIMER_START_BP(VERIFY_line_26_new);
// PAPER LINE 26
std::vector<MultiexpData> multiexp_data;
multiexp_data.reserve(1+2*rounds);
sc_sub(tmp.bytes, rct::zero().bytes, proof.mu.bytes);
rct::addKeys(pprime, P, rct::scalarmultBase(tmp));
for (size_t i = 0; i < rounds; ++i)
{
sc_mul(tmp.bytes, w[i].bytes, w[i].bytes);
sc_mul(tmp2.bytes, winv[i].bytes, winv[i].bytes);
if (!(tmp == rct::zero()))
multiexp_data.push_back({tmp, proof.L[i]});
if (!(tmp2 == rct::zero()))
multiexp_data.push_back({tmp2, proof.R[i]});
}
sc_mul(tmp.bytes, proof.t.bytes, x_ip.bytes);
if (!(tmp == rct::zero()))
multiexp_data.push_back({tmp, rct::H});
addKeys(pprime, pprime, bos_coster_heap_conv_robust(multiexp_data));
PERF_TIMER_STOP(VERIFY_line_26_new);
}
{
PERF_TIMER_START_BP(VERIFY_line_26_old);
// PAPER LINE 26
sc_sub(tmp.bytes, rct::zero().bytes, proof.mu.bytes);
rct::addKeys(pprime, P, rct::scalarmultBase(tmp));
ge_p3 pprime_p3;
CHECK_AND_ASSERT_MES(ge_frombytes_vartime(&pprime_p3, pprime.bytes) == 0, false, "ge_frombytes_vartime failed");
for (size_t i = 0; i < rounds; ++i)
{
sc_mul(tmp.bytes, w[i].bytes, w[i].bytes);
sc_mul(tmp2.bytes, winv[i].bytes, winv[i].bytes);
#if 1
ge_dsmp cacheL, cacheR;
rct::precomp(cacheL, proof.L[i]);
rct::precomp(cacheR, proof.R[i]);
addKeys3acc_p3(&pprime_p3, tmp, cacheL, tmp2, cacheR);
#else
rct::addKeys(pprime, pprime, rct::scalarmultKey(proof.L[i], tmp));
rct::addKeys(pprime, pprime, rct::scalarmultKey(proof.R[i], tmp2));
#endif
}
sc_mul(tmp.bytes, proof.t.bytes, x_ip.bytes);
addKeys_acc_p3(&pprime_p3, tmp, rct::H);
ge_p3_tobytes(pprime.bytes, &pprime_p3);
PERF_TIMER_STOP(VERIFY_line_26_old);
}
sc_mul(tmp.bytes, proof.t.bytes, x_ip.bytes);
addKeys_acc_p3(&pprime_p3, tmp, rct::H);
ge_p3_tobytes(pprime.bytes, &pprime_p3);
PERF_TIMER_STOP(VERIFY_line_26);
PERF_TIMER_START_BP(VERIFY_step2_check);
sc_mul(tmp.bytes, proof.a.bytes, proof.b.bytes);

239
src/ringct/multiexp.cc Normal file
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@ -0,0 +1,239 @@
// Copyright (c) 2017, The Monero Project
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
// conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
// of conditions and the following disclaimer in the documentation and/or other
// materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors may be
// used to endorse or promote products derived from this software without specific
// prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Adapted from Python code by Sarang Noether
#include "misc_log_ex.h"
#include "common/perf_timer.h"
extern "C"
{
#include "crypto/crypto-ops.h"
}
#include "rctOps.h"
#include "multiexp.h"
#undef MONERO_DEFAULT_LOG_CATEGORY
#define MONERO_DEFAULT_LOG_CATEGORY "multiexp.boscoster"
//#define MULTIEXP_PERF(x) x
#define MULTIEXP_PERF(x)
namespace rct
{
static inline bool operator<(const rct::key &k0, const rct::key&k1)
{
for (int n = 31; n >= 0; --n)
{
if (k0.bytes[n] < k1.bytes[n])
return true;
if (k0.bytes[n] > k1.bytes[n])
return false;
}
return false;
}
static inline rct::key div2(const rct::key &k)
{
rct::key res;
int carry = 0;
for (int n = 31; n >= 0; --n)
{
int new_carry = (k.bytes[n] & 1) << 7;
res.bytes[n] = k.bytes[n] / 2 + carry;
carry = new_carry;
}
return res;
}
rct::key bos_coster_heap_conv(std::vector<MultiexpData> &data)
{
MULTIEXP_PERF(PERF_TIMER_START_UNIT(bos_coster, 1000000));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(setup, 1000000));
size_t points = data.size();
CHECK_AND_ASSERT_THROW_MES(points > 1, "Not enough points");
std::vector<size_t> heap(points);
for (size_t n = 0; n < points; ++n)
heap[n] = n;
auto Comp = [&](size_t e0, size_t e1) { return data[e0].scalar < data[e1].scalar; };
std::make_heap(heap.begin(), heap.end(), Comp);
MULTIEXP_PERF(PERF_TIMER_STOP(setup));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(loop, 1000000));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(pop, 1000000)); MULTIEXP_PERF(PERF_TIMER_PAUSE(pop));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(add, 1000000)); MULTIEXP_PERF(PERF_TIMER_PAUSE(add));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(sub, 1000000)); MULTIEXP_PERF(PERF_TIMER_PAUSE(sub));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(push, 1000000)); MULTIEXP_PERF(PERF_TIMER_PAUSE(push));
while (heap.size() > 1)
{
MULTIEXP_PERF(PERF_TIMER_RESUME(pop));
std::pop_heap(heap.begin(), heap.end(), Comp);
size_t index1 = heap.back();
heap.pop_back();
std::pop_heap(heap.begin(), heap.end(), Comp);
size_t index2 = heap.back();
heap.pop_back();
MULTIEXP_PERF(PERF_TIMER_PAUSE(pop));
MULTIEXP_PERF(PERF_TIMER_RESUME(add));
ge_cached cached;
ge_p3_to_cached(&cached, &data[index1].point);
ge_p1p1 p1;
ge_add(&p1, &data[index2].point, &cached);
ge_p1p1_to_p3(&data[index2].point, &p1);
MULTIEXP_PERF(PERF_TIMER_PAUSE(add));
MULTIEXP_PERF(PERF_TIMER_RESUME(sub));
sc_sub(data[index1].scalar.bytes, data[index1].scalar.bytes, data[index2].scalar.bytes);
MULTIEXP_PERF(PERF_TIMER_PAUSE(sub));
MULTIEXP_PERF(PERF_TIMER_RESUME(push));
if (!(data[index1].scalar == rct::zero()))
{
heap.push_back(index1);
std::push_heap(heap.begin(), heap.end(), Comp);
}
heap.push_back(index2);
std::push_heap(heap.begin(), heap.end(), Comp);
MULTIEXP_PERF(PERF_TIMER_PAUSE(push));
}
MULTIEXP_PERF(PERF_TIMER_STOP(push));
MULTIEXP_PERF(PERF_TIMER_STOP(sub));
MULTIEXP_PERF(PERF_TIMER_STOP(add));
MULTIEXP_PERF(PERF_TIMER_STOP(pop));
MULTIEXP_PERF(PERF_TIMER_STOP(loop));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(end, 1000000));
//return rct::scalarmultKey(data[index1].point, data[index1].scalar);
std::pop_heap(heap.begin(), heap.end(), Comp);
size_t index1 = heap.back();
heap.pop_back();
ge_p2 p2;
ge_scalarmult(&p2, data[index1].scalar.bytes, &data[index1].point);
rct::key res;
ge_tobytes(res.bytes, &p2);
return res;
}
rct::key bos_coster_heap_conv_robust(std::vector<MultiexpData> &data)
{
MULTIEXP_PERF(PERF_TIMER_START_UNIT(bos_coster, 1000000));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(setup, 1000000));
size_t points = data.size();
CHECK_AND_ASSERT_THROW_MES(points > 1, "Not enough points");
std::vector<size_t> heap(points);
for (size_t n = 0; n < points; ++n)
heap[n] = n;
auto Comp = [&](size_t e0, size_t e1) { return data[e0].scalar < data[e1].scalar; };
std::make_heap(heap.begin(), heap.end(), Comp);
MULTIEXP_PERF(PERF_TIMER_STOP(setup));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(loop, 1000000));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(pop, 1000000)); MULTIEXP_PERF(PERF_TIMER_PAUSE(pop));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(div, 1000000)); MULTIEXP_PERF(PERF_TIMER_PAUSE(div));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(add, 1000000)); MULTIEXP_PERF(PERF_TIMER_PAUSE(add));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(sub, 1000000)); MULTIEXP_PERF(PERF_TIMER_PAUSE(sub));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(push, 1000000)); MULTIEXP_PERF(PERF_TIMER_PAUSE(push));
while (heap.size() > 1)
{
MULTIEXP_PERF(PERF_TIMER_RESUME(pop));
std::pop_heap(heap.begin(), heap.end(), Comp);
size_t index1 = heap.back();
heap.pop_back();
std::pop_heap(heap.begin(), heap.end(), Comp);
size_t index2 = heap.back();
heap.pop_back();
MULTIEXP_PERF(PERF_TIMER_PAUSE(pop));
ge_cached cached;
ge_p1p1 p1;
MULTIEXP_PERF(PERF_TIMER_RESUME(div));
while (1)
{
rct::key s1_2 = div2(data[index1].scalar);
if (!(data[index2].scalar < s1_2))
break;
if (data[index1].scalar.bytes[0] & 1)
{
data.resize(data.size()+1);
data.back().scalar = rct::identity();
data.back().point = data[index1].point;
heap.push_back(data.size() - 1);
std::push_heap(heap.begin(), heap.end(), Comp);
}
data[index1].scalar = div2(data[index1].scalar);
ge_p3_to_cached(&cached, &data[index1].point);
ge_add(&p1, &data[index1].point, &cached);
ge_p1p1_to_p3(&data[index1].point, &p1);
}
MULTIEXP_PERF(PERF_TIMER_PAUSE(div));
MULTIEXP_PERF(PERF_TIMER_RESUME(add));
ge_p3_to_cached(&cached, &data[index1].point);
ge_add(&p1, &data[index2].point, &cached);
ge_p1p1_to_p3(&data[index2].point, &p1);
MULTIEXP_PERF(PERF_TIMER_PAUSE(add));
MULTIEXP_PERF(PERF_TIMER_RESUME(sub));
sc_sub(data[index1].scalar.bytes, data[index1].scalar.bytes, data[index2].scalar.bytes);
MULTIEXP_PERF(PERF_TIMER_PAUSE(sub));
MULTIEXP_PERF(PERF_TIMER_RESUME(push));
if (!(data[index1].scalar == rct::zero()))
{
heap.push_back(index1);
std::push_heap(heap.begin(), heap.end(), Comp);
}
heap.push_back(index2);
std::push_heap(heap.begin(), heap.end(), Comp);
MULTIEXP_PERF(PERF_TIMER_PAUSE(push));
}
MULTIEXP_PERF(PERF_TIMER_STOP(push));
MULTIEXP_PERF(PERF_TIMER_STOP(sub));
MULTIEXP_PERF(PERF_TIMER_STOP(add));
MULTIEXP_PERF(PERF_TIMER_STOP(pop));
MULTIEXP_PERF(PERF_TIMER_STOP(loop));
MULTIEXP_PERF(PERF_TIMER_START_UNIT(end, 1000000));
//return rct::scalarmultKey(data[index1].point, data[index1].scalar);
std::pop_heap(heap.begin(), heap.end(), Comp);
size_t index1 = heap.back();
heap.pop_back();
ge_p2 p2;
ge_scalarmult(&p2, data[index1].scalar.bytes, &data[index1].point);
rct::key res;
ge_tobytes(res.bytes, &p2);
return res;
}
}

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// Copyright (c) 2017, The Monero Project
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
// conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
// of conditions and the following disclaimer in the documentation and/or other
// materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors may be
// used to endorse or promote products derived from this software without specific
// prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Adapted from Python code by Sarang Noether
#pragma once
#ifndef MULTIEXP_H
#define MULTIEXP_H
#include <vector>
#include "crypto/crypto.h"
#include "rctTypes.h"
namespace rct
{
struct MultiexpData {
rct::key scalar;
ge_p3 point;
MultiexpData() {}
MultiexpData(const rct::key &s, const ge_p3 &p): scalar(s), point(p) {}
MultiexpData(const rct::key &s, const rct::key &p): scalar(s)
{
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&point, p.bytes) == 0, "ge_frombytes_vartime failed");
}
};
rct::key bos_coster_heap_conv(std::vector<MultiexpData> &data);
rct::key bos_coster_heap_conv_robust(std::vector<MultiexpData> &data);
}
#endif