/* LibTomPoly, Polynomial Basis Math -- Tom St Denis * * LibTomPoly is a public domain library that provides * polynomial basis arithmetic support. It relies on * LibTomMath for large integer support. * * This library is free for all purposes without any * express guarantee that it works. * * Tom St Denis, tomstdenis@iahu.ca, http://poly.libtomcrypt.org */ #include int pb_toraw(pb_poly *a, unsigned char *dst) { int err, x, y, z; /* store the # of terms */ dst[0] = a->used & 255; dst[1] = (a->used >> 8) & 255; y = 2; /* store the characteristic */ z = mp_signed_bin_size(&(a->characteristic)); dst[y++] = z&255; dst[y++] = (z>>8)&255; if ((err = mp_to_signed_bin(&(a->characteristic), dst+y)) != MP_OKAY) { return err; } y += z; for (x = 0; x < a->used; x++) { z = mp_signed_bin_size(&(a->terms[x])); dst[y++] = z&255; dst[y++] = (z>>8)&255; if ((err = mp_to_signed_bin(&(a->terms[x]), dst+y)) != MP_OKAY) { return err; } y += z; } return MP_OKAY; }