ringct: luigi1111's changes to fix and speedup Borromean sigs

This commit is contained in:
luigi1111 2016-11-17 23:27:00 +00:00 committed by moneromooo-monero
parent 76958fc75a
commit 46a0dcc1d2
No known key found for this signature in database
GPG Key ID: 686F07454D6CEFC3
2 changed files with 19 additions and 24 deletions

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@ -58,29 +58,28 @@ namespace rct {
//Borromean (c.f. gmax/andytoshi's paper)
boroSig genBorromean(const key64 x, const key64 P1, const key64 P2, const bits indices) {
key64 L[2], c[2], s[2], alpha, P[2];
key64 L[2], alpha;
key c;
int naught = 0, prime = 0, ii = 0, jj=0;
boroSig bb;
for (ii = 0 ; ii < 64 ; ii++) {
naught = indices[ii]; prime = (indices[ii] + 1) % 2;
copy(P[0][ii], P1[ii]); //could probably user pointers
copy(P[1][ii], P2[ii]);
skGen(alpha[ii]);
scalarmultBase(L[naught][ii], alpha[ii]);
c[prime][ii] = hash_to_scalar(L[naught][ii]);
skGen(s[prime][ii]);
addKeys2(L[prime][ii], s[prime][ii], c[prime][ii], P[prime][ii]);
if (naught == 0) {
skGen(bb.s1[ii]);
c = hash_to_scalar(L[naught][ii]);
addKeys2(L[prime][ii], bb.s1[ii], c, P2[ii]);
}
}
boroSig bb;
bb.ee = cn_fast_hash(L[1]); //or L[1]..
bb.ee = hash_to_scalar(L[1]); //or L[1]..
key LL, cc;
for (jj = 0 ; jj < 64 ; jj++) {
naught = indices[jj]; prime = (indices[jj] + 1) % 2;
if (!indices[jj]) {
sc_mulsub(bb.s0[jj].bytes, x[jj].bytes, bb.ee.bytes, alpha[jj].bytes);
copy(bb.s1[jj], s[1][jj]);
} else {
copy(bb.s0[jj], s[0][jj]);
addKeys2(LL, bb.s0[jj], bb.ee, P[0][jj]); //different L0
skGen(bb.s0[jj]);
addKeys2(LL, bb.s0[jj], bb.ee, P1[jj]); //different L0
cc = hash_to_scalar(LL);
sc_mulsub(bb.s1[jj].bytes, x[jj].bytes, cc.bytes, alpha[jj].bytes);
}
@ -90,14 +89,14 @@ namespace rct {
//see above.
bool verifyBorromean(const boroSig &bb, const key64 P1, const key64 P2) {
key64 Lv1, chash; key LL;
key64 Lv1; key chash, LL;
int ii = 0;
for (ii = 0 ; ii < 64 ; ii++) {
addKeys2(LL, bb.s0[ii], bb.ee, P1[ii]);
chash[ii] = hash_to_scalar(LL);
addKeys2(Lv1[ii], bb.s1[ii], chash[ii], P2[ii]);
chash = hash_to_scalar(LL);
addKeys2(Lv1[ii], bb.s1[ii], chash, P2[ii]);
}
key eeComputed = cn_fast_hash(Lv1); //hash function fine
key eeComputed = hash_to_scalar(Lv1); //hash function fine
return equalKeys(eeComputed, bb.ee);
}

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@ -57,19 +57,15 @@ TEST(ringct, Borromean)
xv[j] = skGen();
if ( (int)indi[j] == 0 ) {
P1v[j] = scalarmultBase(xv[j]);
P2v[j] = pkGen();
scalarmultBase(P1v[j], xv[j]);
} else {
P2v[j] = scalarmultBase(xv[j]);
P1v[j] = pkGen();
addKeys1(P1v[j], xv[j], H2[j]);
}
subKeys(P2v[j], P1v[j], H2[j]);
}
//#true one
boro bb = genBorromean(xv, P1v, P2v, indi);
boroSig bb = genBorromean(xv, P1v, P2v, indi);
ASSERT_TRUE(verifyBorromean(bb, P1v, P2v));
//#false one