public static UInt16 get_secret(UInt16[] shares, UInt32 size)
{
UInt32 secret = 0;
// Calculate numerator
for (UInt32 i = 0; i < size; ++i)
{
UInt32 numerator = 1;
UInt32 denominator = 1;
share si = new share(shares[i]);
for (UInt32 j = 0; j < size; ++j)
{
if (i == j)
{
continue;
}
share sj = new share(shares[j]);
numerator = mod_math.mod_multiply(numerator, sj.x);
UInt32 diff = mod_math.mod_subtract(sj.x, si.x);
denominator = mod_math.mod_multiply(diff, denominator);
}
UInt32 invert = mod_math.mod_invert(denominator);
UInt32 ci = mod_math.mod_multiply(numerator, invert);
UInt32 tmp = mod_math.mod_multiply(ci, si.value);
secret = mod_math.mod_add(secret, tmp);
}
return((UInt16)(secret));
}
public UInt16[] make_shares(byte secret_byte)
{
UInt16[] share_array = new UInt16[_shares];
init_coefficients();
_coefficients[(UInt32)(_required) - 1] = secret_byte;
UInt16 x = 1;
for (UInt32 i = 0; i < _shares; ++i, ++x)
{
share s = new share(x, shared_math.make_share(_coefficients, x));
share_array[i] = s.to_uint16();
}
return(share_array);
}