mirror of http://galexander.org/git/simplesshd.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
24 lines
650 B
24 lines
650 B
#include "tommath_private.h"
|
|
#ifdef BN_MP_INVMOD_C
|
|
/* LibTomMath, multiple-precision integer library -- Tom St Denis */
|
|
/* SPDX-License-Identifier: Unlicense */
|
|
|
|
/* hac 14.61, pp608 */
|
|
mp_err mp_invmod(const mp_int *a, const mp_int *b, mp_int *c)
|
|
{
|
|
/* b cannot be negative and has to be >1 */
|
|
if ((b->sign == MP_NEG) || (mp_cmp_d(b, 1uL) != MP_GT)) {
|
|
return MP_VAL;
|
|
}
|
|
|
|
/* if the modulus is odd we can use a faster routine instead */
|
|
if (MP_HAS(S_MP_INVMOD_FAST) && MP_IS_ODD(b)) {
|
|
return s_mp_invmod_fast(a, b, c);
|
|
}
|
|
|
|
return MP_HAS(S_MP_INVMOD_SLOW)
|
|
? s_mp_invmod_slow(a, b, c)
|
|
: MP_VAL;
|
|
}
|
|
#endif
|