PoS_EVM
/
mcl
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

refactor ec::dbl

Browse Source
update-fork
MITSUNARI Shigeo 5 years ago
parent 9c62b3d964
commit 7e6ab212fb
3 changed files with 38 additions and 93 deletions
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Show Stats Download Patch File Download Diff File
  1. 108
      include/mcl/ec.hpp
  2. 17
      include/mcl/mapto_wb19.hpp
  3. 6
      test/mapto_wb19_test.cpp

108
include/mcl/ec.hpp
Unescape View File

@ -117,9 +117,9 @@ bool isValidJacobi(const F& x, const F& y, const F& z, const F& a, const F& b)
} }
/* /*
a = 0 3M + 4S + 12A a = 0 2M + 5S + 14A
a = -3 3M + 6S + 13A a = -3 2M + 7S + 15A
generic 4M + 6S + 13A generic 3M + 7S + 15A
*/ */
template<class E> template<class E>
void dblJacobi(E& R, const E& P, int specialA, const typename E::Fp& a) void dblJacobi(E& R, const E& P, int specialA, const typename E::Fp& a)
@ -129,87 +129,31 @@ void dblJacobi(E& R, const E& P, int specialA, const typename E::Fp& a)
R.clear(); R.clear();
return; return;
} }
#if 0
// a = 0 M + 7S + 15A
// a = -3 M + 8S + 18A
// generic 2M + 8S + 16A
F x2, y2, y4, z2, s, m, t;
F::sqr(x2, P.x);
F::sqr(y2, P.y);
F::sqr(y4, y2);
const bool isPzOne = P.z.isOne(); const bool isPzOne = P.z.isOne();
if (isPzOne) { F x2, y2, xy, t;
z2 = P.z; F::sqr(x2, P.x);
} else {
F::sqr(z2, P.z);
}
F::add(s, P.x, y2);
F::sqr(s, s);
s -= x2;
s -= y4;
s += s;
F::add(m, x2, x2);
m += x2;
switch (specialA) {
case Zero:
break;
case Minus3:
if (isPzOne) {
t = z2;
} else {
F::sqr(t, z2);
}
m -= t;
m -= t;
m -= t;
break;
case GenericA:
default:
if (isPzOne) {
m += a;
} else {
F::sqr(t, z2);
t *= a;
m += t;
}
break;
}
F::sqr(t, m);
t -= s;
F::sub(R.x, t, s); // m^2 - 2s
F::add(R.z, P.y, P.z);
F::sqr(R.z, R.z);
R.z -= y2;
R.z -= z2;
F::sub(R.y, s, R.x);
R.y *= m;
F::add(t, y4, y4);
t += t;
t += t;
R.y -= t;
#else
F S, M, t, y2;
F::sqr(y2, P.y); F::sqr(y2, P.y);
F::mul(S, P.x, y2); F::add(xy, P.x, y2);
const bool isPzOne = P.z.isOne(); F::sqr(y2, y2);
S += S; F::sqr(xy, xy);
S += S; xy -= x2;
F::sqr(M, P.x); xy -= y2;
xy += xy;
switch (specialA) { switch (specialA) {
case Zero: case Zero:
F::add(t, M, M); F::add(t, x2, x2);
M += t; x2 += t;
break; break;
case Minus3: case Minus3:
if (isPzOne) { if (isPzOne) {
M -= P.z; x2 -= P.z;
} else { } else {
F::sqr(t, P.z); F::sqr(t, P.z);
F::sqr(t, t); F::sqr(t, t);
M -= t; x2 -= t;
} }
F::add(t, M, M); F::add(t, x2, x2);
M += t; x2 += t;
break; break;
case GenericA: case GenericA:
default: default:
@ -220,28 +164,26 @@ void dblJacobi(E& R, const E& P, int specialA, const typename E::Fp& a)
F::sqr(t, t); F::sqr(t, t);
t *= a; t *= a;
} }
t += M; t += x2;
M += M; x2 += x2;
M += t; x2 += t;
break; break;
} }
F::sqr(R.x, M); F::sqr(R.x, x2);
R.x -= S; R.x -= xy;
R.x -= S; R.x -= xy;
if (isPzOne) { if (isPzOne) {
R.z = P.y; R.z = P.y;
} else { } else {
F::mul(R.z, P.y, P.z); F::mul(R.z, P.y, P.z);
} }
R.z += R.z; R.z += R.z;
F::sqr(y2, y2); F::sub(R.y, xy, R.x);
R.y *= x2;
y2 += y2; y2 += y2;
y2 += y2; y2 += y2;
y2 += y2; y2 += y2;
F::sub(R.y, S, R.x);
R.y *= M;
R.y -= y2; R.y -= y2;
#endif
} }
// 7M + 4S + 7A // 7M + 4S + 7A

17
include/mcl/mapto_wb19.hpp
Unescape View File

@ -135,14 +135,14 @@ struct MapToG2_WB19 {
R.y -= S1; R.y -= S1;
R.y -= S1; R.y -= S1;
} }
// jacobi : sqr 5, mul 2, add 14 // jacobi : 2M + 5S + 14A
template<class G> template<class G>
void dblT(G& Q, const G& P) const void dblT(G& Q, const G& P) const
{ {
#if 0 #if 0
ec::dblJacobi(Q, P, ec::GenericA, Ell2p_a); ec::dblJacobi(Q, P, ec::GenericA, Ell2p_a);
#else #else
Fp2 A, B, C, D, E, F; Fp2 A, B, C, D, e, f;
Fp2::sqr(A, P.x); Fp2::sqr(A, P.x);
Fp2::sqr(B, P.y); Fp2::sqr(B, P.y);
Fp2::sqr(C, B); Fp2::sqr(C, B);
@ -151,10 +151,10 @@ struct MapToG2_WB19 {
D -= A; D -= A;
D -= C; D -= C;
D += D; D += D;
Fp2::add(E, A, A); Fp2::add(e, A, A);
E += A; e += A;
Fp2::sqr(F, E); Fp2::sqr(f, e);
Fp2::sub(Q.x, F, D); Fp2::sub(Q.x, f, D);
Q.x -= D; Q.x -= D;
Fp2::mul(Q.z, P.y, P.z); Fp2::mul(Q.z, P.y, P.z);
if (Q.z.isZero()) { if (Q.z.isZero()) {
@ -164,7 +164,7 @@ struct MapToG2_WB19 {
} }
Q.z += Q.z; Q.z += Q.z;
Fp2::sub(Q.y, D, Q.x); Fp2::sub(Q.y, D, Q.x);
Q.y *= E; Q.y *= e;
C += C; C += C;
C += C; C += C;
C += C; C += C;
@ -178,6 +178,7 @@ struct MapToG2_WB19 {
void dbl(G2& Q, const G2& P) const void dbl(G2& Q, const G2& P) const
{ {
dblT(Q, P); dblT(Q, P);
// G2::dbl(Q, P);
} }
// P is on y^2 = x^3 + Ell2p_a x + Ell2p_b // P is on y^2 = x^3 + Ell2p_a x + Ell2p_b
bool isValidPoint(const Point& P) const bool isValidPoint(const Point& P) const
@ -301,6 +302,7 @@ struct MapToG2_WB19 {
// refer (xnum, xden, ynum, yden) // refer (xnum, xden, ynum, yden)
void iso3(G2& Q, const Point& P) const void iso3(G2& Q, const Point& P) const
{ {
// assert(isValidPoint(P));
Fp2 zpows[3]; Fp2 zpows[3];
Fp2::sqr(zpows[0], P.z); Fp2::sqr(zpows[0], P.z);
Fp2::sqr(zpows[1], zpows[0]); Fp2::sqr(zpows[1], zpows[0]);
@ -321,6 +323,7 @@ struct MapToG2_WB19 {
Fp2::sqr(t, Q.z); Fp2::sqr(t, Q.z);
Fp2::mul(Q.y, mapvals[2], mapvals[1]); Fp2::mul(Q.y, mapvals[2], mapvals[1]);
Q.y *= t; Q.y *= t;
// assert(Q.isValid());
} }
/* /*
(a+bi)*(-2-i) = (b-2a)-(a+2b)i (a+bi)*(-2-i) = (b-2a)-(a+2b)i

6
test/mapto_wb19_test.cpp
Unescape View File

@ -688,9 +688,9 @@ void testHashToFp2v6(const T& mapto)
Fp2 out[2]; Fp2 out[2];
mapto.hashToFp2v6(out, msg, strlen(msg), dst, strlen(dst)); mapto.hashToFp2v6(out, msg, strlen(msg), dst, strlen(dst));
Fp2 expect[2]; Fp2 expect[2];
for (int i = 0; i < 2; i++) { for (int j = 0; j < 2; j++) {
set(expect[i], expectStr[i]); set(expect[j], expectStr[j]);
CYBOZU_TEST_EQUAL(out[i], expect[i]); CYBOZU_TEST_EQUAL(out[j], expect[j]);
} }
if (i == 0) { if (i == 0) {
// from draft-irtf-cfrg-hash-to-curve/poc/vectors/BLS12381G2_XMD:SHA-256_SSWU_RO_.json.swp // from draft-irtf-cfrg-hash-to-curve/poc/vectors/BLS12381G2_XMD:SHA-256_SSWU_RO_.json.swp

Write Preview
Loading…
Cancel
Save