public static void ContextBuild(EcmultGenContext ctx, EventHandler <Callback> cb)
{
Ge[] r1 = new Ge[1024];
GeJ r2 = new GeJ();
GeJ geJ1 = new GeJ();
if (ctx.Prec != null)
{
return;
}
ctx.PrecInit();
Group.secp256k1_gej_set_ge(r2, Group.Secp256K1GeConstG);
byte[] bytes = Encoding.UTF8.GetBytes("The scalar for this x is unknown");
Fe fe = new Fe();
Ge ge = new Ge();
Field.SetB32(fe, bytes);
Group.secp256k1_ge_set_xo_var(ge, fe, false);
Group.secp256k1_gej_set_ge(geJ1, ge);
Group.secp256k1_gej_add_ge_var(geJ1, geJ1, Group.Secp256K1GeConstG, (Fe)null);
GeJ[] a = new GeJ[1024];
for (int index = 0; index < a.Length; ++index)
{
a[index] = new GeJ();
}
GeJ geJ2 = r2.Clone();
GeJ geJ3 = geJ1.Clone();
for (int index1 = 0; index1 < 64; ++index1)
{
a[index1 * 16] = geJ3.Clone();
for (int index2 = 1; index2 < 16; ++index2)
{
Group.secp256k1_gej_add_var(a[index1 * 16 + index2], a[index1 * 16 + index2 - 1], geJ2, (Fe)null);
}
for (int index2 = 0; index2 < 4; ++index2)
{
Group.secp256k1_gej_double_var(geJ2, geJ2, (Fe)null);
}
Group.secp256k1_gej_double_var(geJ3, geJ3, (Fe)null);
if (index1 == 62)
{
Group.secp256k1_gej_neg(geJ3, geJ3);
Group.secp256k1_gej_add_var(geJ3, geJ3, geJ1, (Fe)null);
}
}
for (int index = 0; index < r1.Length; ++index)
{
r1[index] = new Ge();
}
Group.secp256k1_ge_set_all_gej_var(r1, a, 1024, cb);
for (int index1 = 0; index1 < 64; ++index1)
{
for (int index2 = 0; index2 < 16; ++index2)
{
Group.ToStorage(ctx.Prec[index1][index2], r1[index1 * 16 + index2]);
}
}
EcMultGen.Blind(ctx, (byte[])null);
}
public static void secp256k1_ecmult_odd_multiples_table_storage_var(int n, GeStorage[] pre, GeJ a, EventHandler <Callback> cb)
{
GeJ[] geJArray = new GeJ[n];
Ge[] r = new Ge[n];
Fe[] zr = new Fe[n];
for (int index = 0; index < n; ++index)
{
geJArray[index] = new GeJ();
r[index] = new Ge();
zr[index] = new Fe();
}
EcMult.secp256k1_ecmult_odd_multiples_table(n, geJArray, zr, a);
Group.secp256k1_ge_set_table_gej_var(r, geJArray, zr, n);
for (int index = 0; index < n; ++index)
{
Group.ToStorage(pre[index], r[index]);
}
}
///** Fill a table 'pre' with precomputed odd multiples of a.
// *
// * There are two versions of this function:
// * - secp256k1_ecmult_odd_multiples_table_globalz_windowa which brings its
// * resulting point set to a single constant Z denominator, stores the X and Y
// * coordinates as ge_storage points in pre, and stores the global Z in rz.
// * It only operates on tables sized for WINDOW_A wnaf multiples.
// * - secp256k1_ecmult_odd_multiples_table_storage_var, which converts its
// * resulting point set to actually affine points, and stores those in pre.
// * It operates on tables of any size, but uses heap-allocated temporaries.
// *
// * To compute a*P + b*G, we compute a table for P using the first function,
// * and for G using the second (which requires an inverse, but it only needs to
// * happen once).
// */
//static void secp256k1_ecmult_odd_multiples_table_globalz_windowa(secp256k1_ge* pre, secp256k1_fe* globalz, const secp256k1_gej* a)
//{
// secp256k1_gej prej[ECMULT_TABLE_SIZE(WINDOW_A)];
// secp256k1_fe zr[ECMULT_TABLE_SIZE(WINDOW_A)];
// /* Compute the odd multiples in Jacobian form. */
// secp256k1_ecmult_odd_multiples_table(ECMULT_TABLE_SIZE(WINDOW_A), prej, zr, a);
// /* Bring them to the same Z denominator. */
// secp256k1_ge_globalz_set_table_gej(ECMULT_TABLE_SIZE(WINDOW_A), pre, globalz, prej, zr);
//}
public static void secp256k1_ecmult_odd_multiples_table_storage_var(int n, GeStorage[] pre, GeJ a, EventHandler <Callback> cb)
{
GeJ[] prej = new GeJ[n];
Ge[] prea = new Ge[n];
Fe[] zr = new Fe[n];
for (int i = 0; i < n; i++)
{
prej[i] = new GeJ();
prea[i] = new Ge();
zr[i] = new Fe();
}
/* Compute the odd multiples in Jacobian form. */
secp256k1_ecmult_odd_multiples_table(n, prej, zr, a);
/* Convert them in batch to affine coordinates. */
Group.secp256k1_ge_set_table_gej_var(prea, prej, zr, n);
/* Convert them to compact storage form. */
for (var i = 0; i < n; i++)
{
Group.ToStorage(pre[i], prea[i]);
}
}
public static void ContextBuild(EcmultGenContext ctx, EventHandler <Callback> cb)
{
#if !USE_ECMULT_STATIC_PRECOMPUTATION
Ge[] prec = new Ge[1024];
GeJ gj = new GeJ();
GeJ numsGej = new GeJ();
int i, j;
#endif
if (ctx.Prec != null)
{
return;
}
#if !USE_ECMULT_STATIC_PRECOMPUTATION
ctx.PrecInit();
/* get the generator */
Group.secp256k1_gej_set_ge(gj, Group.Secp256K1GeConstG);
/* Construct a group element with no known corresponding scalar (nothing up my sleeve). */
{
var numsB32 = Encoding.UTF8.GetBytes("The scalar for this x is unknown");
Fe numsX = new Fe();
Ge numsGe = new Ge();
var r = Field.SetB32(numsX, numsB32);
//(void)r;
Util.VERIFY_CHECK(r);
r = Group.secp256k1_ge_set_xo_var(numsGe, numsX, false);
//(void)r;
Util.VERIFY_CHECK(r);
Group.secp256k1_gej_set_ge(numsGej, numsGe);
/* Add G to make the bits in x uniformly distributed. */
Group.secp256k1_gej_add_ge_var(numsGej, numsGej, Group.Secp256K1GeConstG, null);
}
/* compute prec. */
{
GeJ[] precj = new GeJ[1024]; /* Jacobian versions of prec. */
for (int k = 0; k < precj.Length; k++)
{
precj[k] = new GeJ();
}
GeJ gbase;
GeJ numsbase;
gbase = gj.Clone(); /* 16^j * G */
numsbase = numsGej.Clone(); /* 2^j * nums. */
for (j = 0; j < 64; j++)
{
/* Set precj[j*16 .. j*16+15] to (numsbase, numsbase + gbase, ..., numsbase + 15*gbase). */
precj[j * 16] = numsbase.Clone();
for (i = 1; i < 16; i++)
{
Group.secp256k1_gej_add_var(precj[j * 16 + i], precj[j * 16 + i - 1], gbase, null);
}
/* Multiply gbase by 16. */
for (i = 0; i < 4; i++)
{
Group.secp256k1_gej_double_var(gbase, gbase, null);
}
/* Multiply numbase by 2. */
Group.secp256k1_gej_double_var(numsbase, numsbase, null);
if (j == 62)
{
/* In the last iteration, numsbase is (1 - 2^j) * nums instead. */
Group.secp256k1_gej_neg(numsbase, numsbase);
Group.secp256k1_gej_add_var(numsbase, numsbase, numsGej, null);
}
}
for (int k = 0; k < prec.Length; k++)
{
prec[k] = new Ge();
}
Group.secp256k1_ge_set_all_gej_var(prec, precj, 1024, cb);
}
for (j = 0; j < 64; j++)
{
for (i = 0; i < 16; i++)
{
Group.ToStorage(ctx.Prec[j][i], prec[j * 16 + i]);
}
}
#else
(void)cb;
ctx.prec = (secp256k1_ge_storage(*)[64][16])secp256k1_ecmult_static_context;