static void addMinimal1Dmats4dim(FHESecKey& sKey, long i, long keyID)
{
const PAlgebra& zMStar = sKey.getContext().zMStar;
long ord;
bool native;
if (i != -1) {
ord = zMStar.OrderOf(i);
native = zMStar.SameOrd(i);\
}
else {
// Frobenius
ord = zMStar.getOrdP();
native = true;
}
sKey.GenKeySWmatrix(1, zMStar.genToPow(i, 1), keyID, keyID);
if (!native)
sKey.GenKeySWmatrix(1, zMStar.genToPow(i, -ord), keyID, keyID);
if (ord > FHE_KEYSWITCH_MIN_THRESH) {
long g = KSGiantStepSize(ord);
sKey.GenKeySWmatrix(1, zMStar.genToPow(i, g), keyID, keyID);
}
sKey.setKSStrategy(i, FHE_KSS_MIN);
}
// same as above, but uses BS/GS strategy
static void addSome1Dmats4dim(FHESecKey& sKey, long i, long bound, long keyID)
{
const PAlgebra& zMStar = sKey.getContext().zMStar;
long ord;
bool native;
if (i != -1) {
ord = zMStar.OrderOf(i);
native = zMStar.SameOrd(i);\
}
else {
// Frobenius
ord = zMStar.getOrdP();
native = true;
}
long g = KSGiantStepSize(ord);
// baby steps
for (long j = 1; j < g; j++)
sKey.GenKeySWmatrix(1, zMStar.genToPow(i, j), keyID, keyID);
// giant steps
for (long j = g; j < ord; j += g)
sKey.GenKeySWmatrix(1, zMStar.genToPow(i, j), keyID, keyID);
if (!native)
sKey.GenKeySWmatrix(1, zMStar.genToPow(i, -ord), keyID, keyID);
sKey.setKSStrategy(i, FHE_KSS_BSGS);
// NOTE: the old code also added matrices for ord-2^k for small k,
// in the case of (native && i<context.zMStar.numOfGens()).
// This supposedly speeds up the replication code, but for now
// we are leaving this out, for simplicity. Also, it is a waste
// of space for applications that don't use replication.
}
// adds all matrices for dim i.
// i == -1 => Frobenius (NOTE: in matmul1D, i ==#gens means something else,
// so it is best to avoid that).
static void add1Dmats4dim(FHESecKey& sKey, long i, long keyID)
{
const PAlgebra& zMStar = sKey.getContext().zMStar;
long ord;
bool native;
if (i != -1) {
ord = zMStar.OrderOf(i);
native = zMStar.SameOrd(i);\
}
else {
// Frobenius
ord = zMStar.getOrdP();
native = true;
}
for (long j = 1; j < ord; j++)
sKey.GenKeySWmatrix(1, zMStar.genToPow(i, j), keyID, keyID);
if (!native)
sKey.GenKeySWmatrix(1, zMStar.genToPow(i, -ord), keyID, keyID);
sKey.setKSStrategy(i, FHE_KSS_FULL);
}