lib/hcrypto/libtommath/bn_mp_sqr.c

   1 #include "tommath_private.h"
   2 #ifdef BN_MP_SQR_C
   3 /* LibTomMath, multiple-precision integer library -- Tom St Denis */
   4 /* SPDX-License-Identifier: Unlicense */
   5
   6 /* computes b = a*a */
   7 mp_err mp_sqr(const mp_int *a, mp_int *b)
   8 {
   9    mp_err err;
  10    if (MP_HAS(S_MP_TOOM_SQR) && /* use Toom-Cook? */
  11        (a->used >= MP_TOOM_SQR_CUTOFF)) {
  12       err = s_mp_toom_sqr(a, b);
  13    } else if (MP_HAS(S_MP_KARATSUBA_SQR) &&  /* Karatsuba? */
  14               (a->used >= MP_KARATSUBA_SQR_CUTOFF)) {
  15       err = s_mp_karatsuba_sqr(a, b);
  16    } else if (MP_HAS(S_MP_SQR_FAST) && /* can we use the fast comba multiplier? */
  17               (((a->used * 2) + 1) < MP_WARRAY) &&
  18               (a->used < (MP_MAXFAST / 2))) {
  19       err = s_mp_sqr_fast(a, b);
  20    } else if (MP_HAS(S_MP_SQR)) {
  21       err = s_mp_sqr(a, b);
  22    } else {
  23       err = MP_VAL;
  24    }
  25    b->sign = MP_ZPOS;
  26    return err;
  27 }
  28 #endif