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hcrypto: import libtommath v1.2.0

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This commit is contained in:
Luke Howard
2020-04-12 18:37:13 +10:00
parent 7181c109d0
commit c403b66082
287 changed files with 28273 additions and 38374 deletions
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104
lib/hcrypto/libtommath/bn_mp_mul.c
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@@ -1,66 +1,52 @@
#include <tommath.h>
#include "tommath_private.h"
#ifdef BN_MP_MUL_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
* LibTomMath is a library that provides multiple-precision
* integer arithmetic as well as number theoretic functionality.
*
* The library was designed directly after the MPI library by
* Michael Fromberger but has been written from scratch with
* additional optimizations in place.
*
* The library is free for all purposes without any express
* guarantee it works.
*
* Tom St Denis, tomstdenis@gmail.com, http://libtom.org
*/
/* LibTomMath, multiple-precision integer library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
/* high level multiplication (handles sign) */
int mp_mul (mp_int * a, mp_int * b, mp_int * c)
mp_err mp_mul(const mp_int *a, const mp_int *b, mp_int *c)
{
int res, neg;
neg = (a->sign == b->sign) ? MP_ZPOS : MP_NEG;
mp_err err;
int min_len = MP_MIN(a->used, b->used),
max_len = MP_MAX(a->used, b->used),
digs = a->used + b->used + 1;
mp_sign neg = (a->sign == b->sign) ? MP_ZPOS : MP_NEG;
/* use Toom-Cook? */
#ifdef BN_MP_TOOM_MUL_C
if (MIN (a->used, b->used) >= TOOM_MUL_CUTOFF) {
res = mp_toom_mul(a, b, c);
} else
#endif
#ifdef BN_MP_KARATSUBA_MUL_C
/* use Karatsuba? */
if (MIN (a->used, b->used) >= KARATSUBA_MUL_CUTOFF) {
res = mp_karatsuba_mul (a, b, c);
} else
#endif
{
/* can we use the fast multiplier?
*
* The fast multiplier can be used if the output will
* have less than MP_WARRAY digits and the number of
* digits won't affect carry propagation
*/
int digs = a->used + b->used + 1;
#ifdef BN_FAST_S_MP_MUL_DIGS_C
if ((digs < MP_WARRAY) &&
MIN(a->used, b->used) <=
(1 << ((CHAR_BIT * sizeof (mp_word)) - (2 * DIGIT_BIT)))) {
res = fast_s_mp_mul_digs (a, b, c, digs);
} else
#endif
#ifdef BN_S_MP_MUL_DIGS_C
res = s_mp_mul (a, b, c); /* uses s_mp_mul_digs */
#else
res = MP_VAL;
#endif
}
c->sign = (c->used > 0) ? neg : MP_ZPOS;
return res;
if (MP_HAS(S_MP_BALANCE_MUL) &&
/* Check sizes. The smaller one needs to be larger than the Karatsuba cut-off.
* The bigger one needs to be at least about one MP_KARATSUBA_MUL_CUTOFF bigger
* to make some sense, but it depends on architecture, OS, position of the
* stars... so YMMV.
* Using it to cut the input into slices small enough for fast_s_mp_mul_digs
* was actually slower on the author's machine, but YMMV.
*/
(min_len >= MP_KARATSUBA_MUL_CUTOFF) &&
((max_len / 2) >= MP_KARATSUBA_MUL_CUTOFF) &&
/* Not much effect was observed below a ratio of 1:2, but again: YMMV. */
(max_len >= (2 * min_len))) {
err = s_mp_balance_mul(a,b,c);
} else if (MP_HAS(S_MP_TOOM_MUL) &&
(min_len >= MP_TOOM_MUL_CUTOFF)) {
err = s_mp_toom_mul(a, b, c);
} else if (MP_HAS(S_MP_KARATSUBA_MUL) &&
(min_len >= MP_KARATSUBA_MUL_CUTOFF)) {
err = s_mp_karatsuba_mul(a, b, c);
} else if (MP_HAS(S_MP_MUL_DIGS_FAST) &&
/* can we use the fast multiplier?
*
* The fast multiplier can be used if the output will
* have less than MP_WARRAY digits and the number of
* digits won't affect carry propagation
*/
(digs < MP_WARRAY) &&
(min_len <= MP_MAXFAST)) {
err = s_mp_mul_digs_fast(a, b, c, digs);
} else if (MP_HAS(S_MP_MUL_DIGS)) {
err = s_mp_mul_digs(a, b, c, digs);
} else {
err = MP_VAL;
}
c->sign = (c->used > 0) ? neg : MP_ZPOS;
return err;
}
#endif
/* $Source: /cvs/libtom/libtommath/bn_mp_mul.c,v $ */
/* $Revision: 1.4 $ */
/* $Date: 2006/12/28 01:25:13 $ */