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authorSteffen Jaeckel <s_jaeckel@gmx.de>2019-09-16 15:50:38 +0200
committerSteffen Jaeckel <s_jaeckel@gmx.de>2019-09-16 15:50:38 +0200
commit577b7c01fef2c4dd6ec499398e64aa2adeda7e8f (patch)
tree8d6f745fddd3a9c170f7c98603518f77b515da4f /libtommath/bn_s_mp_sub.c
parent663fc015dbb5b39ac6be6630a003f0530af734fb (diff)
downloaddropbear-577b7c01fef2c4dd6ec499398e64aa2adeda7e8f.tar.gz
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_sub.c')
-rw-r--r--libtommath/bn_s_mp_sub.c114
1 files changed, 55 insertions, 59 deletions
diff --git a/libtommath/bn_s_mp_sub.c b/libtommath/bn_s_mp_sub.c
index 8091f4a..c59ebef 100644
--- a/libtommath/bn_s_mp_sub.c
+++ b/libtommath/bn_s_mp_sub.c
@@ -1,4 +1,4 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
#ifdef BN_S_MP_SUB_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
@@ -9,81 +9,77 @@
* 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
*/
/* low level subtraction (assumes |a| > |b|), HAC pp.595 Algorithm 14.9 */
-int
-s_mp_sub (mp_int * a, mp_int * b, mp_int * c)
+int s_mp_sub(const mp_int *a, const mp_int *b, mp_int *c)
{
- int olduse, res, min, max;
+ int olduse, res, min, max;
- /* find sizes */
- min = b->used;
- max = a->used;
+ /* find sizes */
+ min = b->used;
+ max = a->used;
- /* init result */
- if (c->alloc < max) {
- if ((res = mp_grow (c, max)) != MP_OKAY) {
- return res;
- }
- }
- olduse = c->used;
- c->used = max;
+ /* init result */
+ if (c->alloc < max) {
+ if ((res = mp_grow(c, max)) != MP_OKAY) {
+ return res;
+ }
+ }
+ olduse = c->used;
+ c->used = max;
- {
- mp_digit u, *tmpa, *tmpb, *tmpc;
- int i;
+ {
+ mp_digit u, *tmpa, *tmpb, *tmpc;
+ int i;
- /* alias for digit pointers */
- tmpa = a->dp;
- tmpb = b->dp;
- tmpc = c->dp;
+ /* alias for digit pointers */
+ tmpa = a->dp;
+ tmpb = b->dp;
+ tmpc = c->dp;
- /* set carry to zero */
- u = 0;
- for (i = 0; i < min; i++) {
- /* T[i] = A[i] - B[i] - U */
- *tmpc = (*tmpa++ - *tmpb++) - u;
+ /* set carry to zero */
+ u = 0;
+ for (i = 0; i < min; i++) {
+ /* T[i] = A[i] - B[i] - U */
+ *tmpc = (*tmpa++ - *tmpb++) - u;
- /* U = carry bit of T[i]
- * Note this saves performing an AND operation since
- * if a carry does occur it will propagate all the way to the
- * MSB. As a result a single shift is enough to get the carry
- */
- u = *tmpc >> ((mp_digit)((CHAR_BIT * sizeof(mp_digit)) - 1));
+ /* U = carry bit of T[i]
+ * Note this saves performing an AND operation since
+ * if a carry does occur it will propagate all the way to the
+ * MSB. As a result a single shift is enough to get the carry
+ */
+ u = *tmpc >> (((size_t)CHAR_BIT * sizeof(mp_digit)) - 1u);
- /* Clear carry from T[i] */
- *tmpc++ &= MP_MASK;
- }
+ /* Clear carry from T[i] */
+ *tmpc++ &= MP_MASK;
+ }
- /* now copy higher words if any, e.g. if A has more digits than B */
- for (; i < max; i++) {
- /* T[i] = A[i] - U */
- *tmpc = *tmpa++ - u;
+ /* now copy higher words if any, e.g. if A has more digits than B */
+ for (; i < max; i++) {
+ /* T[i] = A[i] - U */
+ *tmpc = *tmpa++ - u;
- /* U = carry bit of T[i] */
- u = *tmpc >> ((mp_digit)((CHAR_BIT * sizeof(mp_digit)) - 1));
+ /* U = carry bit of T[i] */
+ u = *tmpc >> (((size_t)CHAR_BIT * sizeof(mp_digit)) - 1u);
- /* Clear carry from T[i] */
- *tmpc++ &= MP_MASK;
- }
+ /* Clear carry from T[i] */
+ *tmpc++ &= MP_MASK;
+ }
- /* clear digits above used (since we may not have grown result above) */
- for (i = c->used; i < olduse; i++) {
- *tmpc++ = 0;
- }
- }
+ /* clear digits above used (since we may not have grown result above) */
+ for (i = c->used; i < olduse; i++) {
+ *tmpc++ = 0;
+ }
+ }
- mp_clamp (c);
- return MP_OKAY;
+ mp_clamp(c);
+ 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 */