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authorSteffen Jaeckel <s_jaeckel@gmx.de>2019-09-16 15:50:38 +0200
committerMatt Johnston <matt@ucc.asn.au>2019-09-16 21:50:38 +0800
commit615ed4e46a52b6bfe0bfc581b8c2fbcc6cc488d1 (patch)
tree12b2ba29ae4c42fc65d64d43968c5d03ab3f4452 /libtommath/bn_s_mp_mul_digs.c
parentfa116e983b4931010e1082dd5c8bf38bbc77718c (diff)
update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79)
* make key-generation compliant to FIPS 186.4 * fix includes in tommath_class.h * update fuzzcorpus instead of error-out * fixup fuzzing make-targets * update Makefile.in * apply necessary patches to ltm sources * clean-up not required ltm files * update to vanilla ltm 1.1.0 this already only contains the required files * remove set/get double
Diffstat (limited to 'libtommath/bn_s_mp_mul_digs.c')
-rw-r--r--libtommath/bn_s_mp_mul_digs.c119
1 files changed, 58 insertions, 61 deletions
diff --git a/libtommath/bn_s_mp_mul_digs.c b/libtommath/bn_s_mp_mul_digs.c
index 8f1bf97..0bab02f 100644
--- a/libtommath/bn_s_mp_mul_digs.c
+++ b/libtommath/bn_s_mp_mul_digs.c
@@ -1,4 +1,4 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
#ifdef BN_S_MP_MUL_DIGS_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
@@ -9,82 +9,79 @@
* 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, tstdenis82@gmail.com, http://libtom.org
+ * SPDX-License-Identifier: Unlicense
*/
/* multiplies |a| * |b| and only computes upto digs digits of result
- * HAC pp. 595, Algorithm 14.12 Modified so you can control how
+ * HAC pp. 595, Algorithm 14.12 Modified so you can control how
* many digits of output are created.
*/
-int s_mp_mul_digs (mp_int * a, mp_int * b, mp_int * c, int digs)
+int s_mp_mul_digs(const mp_int *a, const mp_int *b, mp_int *c, int digs)
{
- mp_int t;
- int res, pa, pb, ix, iy;
- mp_digit u;
- mp_word r;
- mp_digit tmpx, *tmpt, *tmpy;
+ mp_int t;
+ int res, pa, pb, ix, iy;
+ mp_digit u;
+ mp_word r;
+ mp_digit tmpx, *tmpt, *tmpy;
+
+ /* can we use the fast multiplier? */
+ if ((digs < (int)MP_WARRAY) &&
+ (MIN(a->used, b->used) <
+ (int)(1u << (((size_t)CHAR_BIT * sizeof(mp_word)) - (2u * (size_t)DIGIT_BIT))))) {
+ return fast_s_mp_mul_digs(a, b, c, digs);
+ }
+
+ if ((res = mp_init_size(&t, digs)) != MP_OKAY) {
+ return res;
+ }
+ t.used = digs;
- /* can we use the fast multiplier? */
- if (((digs) < MP_WARRAY) &&
- (MIN (a->used, b->used) <
- (1 << ((CHAR_BIT * sizeof(mp_word)) - (2 * DIGIT_BIT))))) {
- return fast_s_mp_mul_digs (a, b, c, digs);
- }
+ /* compute the digits of the product directly */
+ pa = a->used;
+ for (ix = 0; ix < pa; ix++) {
+ /* set the carry to zero */
+ u = 0;
- if ((res = mp_init_size (&t, digs)) != MP_OKAY) {
- return res;
- }
- t.used = digs;
+ /* limit ourselves to making digs digits of output */
+ pb = MIN(b->used, digs - ix);
- /* compute the digits of the product directly */
- pa = a->used;
- for (ix = 0; ix < pa; ix++) {
- /* set the carry to zero */
- u = 0;
+ /* setup some aliases */
+ /* copy of the digit from a used within the nested loop */
+ tmpx = a->dp[ix];
- /* limit ourselves to making digs digits of output */
- pb = MIN (b->used, digs - ix);
+ /* an alias for the destination shifted ix places */
+ tmpt = t.dp + ix;
- /* setup some aliases */
- /* copy of the digit from a used within the nested loop */
- tmpx = a->dp[ix];
-
- /* an alias for the destination shifted ix places */
- tmpt = t.dp + ix;
-
- /* an alias for the digits of b */
- tmpy = b->dp;
+ /* an alias for the digits of b */
+ tmpy = b->dp;
- /* compute the columns of the output and propagate the carry */
- for (iy = 0; iy < pb; iy++) {
- /* compute the column as a mp_word */
- r = (mp_word)*tmpt +
- ((mp_word)tmpx * (mp_word)*tmpy++) +
- (mp_word)u;
+ /* compute the columns of the output and propagate the carry */
+ for (iy = 0; iy < pb; iy++) {
+ /* compute the column as a mp_word */
+ r = (mp_word)*tmpt +
+ ((mp_word)tmpx * (mp_word)*tmpy++) +
+ (mp_word)u;
- /* the new column is the lower part of the result */
- *tmpt++ = (mp_digit) (r & ((mp_word) MP_MASK));
+ /* the new column is the lower part of the result */
+ *tmpt++ = (mp_digit)(r & (mp_word)MP_MASK);
- /* get the carry word from the result */
- u = (mp_digit) (r >> ((mp_word) DIGIT_BIT));
- }
- /* set carry if it is placed below digs */
- if ((ix + iy) < digs) {
- *tmpt = u;
- }
- }
+ /* get the carry word from the result */
+ u = (mp_digit)(r >> (mp_word)DIGIT_BIT);
+ }
+ /* set carry if it is placed below digs */
+ if ((ix + iy) < digs) {
+ *tmpt = u;
+ }
+ }
- mp_clamp (&t);
- mp_exch (&t, c);
+ mp_clamp(&t);
+ mp_exch(&t, c);
- mp_clear (&t);
- return MP_OKAY;
+ mp_clear(&t);
+ return MP_OKAY;
}
#endif
-/* ref: $Format:%D$ */
-/* git commit: $Format:%H$ */
-/* commit time: $Format:%ai$ */
+/* ref: HEAD -> master, tag: v1.1.0 */
+/* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
+/* commit time: 2019-01-28 20:32:32 +0100 */