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view libtommath/bn_mp_invmod.c @ 1665:7c17995bcdfb

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Improve address logging on early exit messages (#83) Change 'Early exit' and 'Exit before auth' messages to include the IP address & port as part of the message. This allows log scanning utilities such as 'fail2ban' to obtain the offending IP address as part of the failure event instead of extracting the PID from the message and then scanning the log again for match 'child connection from' messages Signed-off-by: Kevin Darbyshire-Bryant <[email protected]>
author Kevin Darbyshire-Bryant <6500011+ldir-EDB0@users.noreply.github.com>
date Wed, 18 Mar 2020 15:28:56 +0000
parents f52919ffd3b1
children 1051e4eea25a
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#include "tommath_private.h"
#ifdef BN_MP_INVMOD_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.
 *
 * SPDX-License-Identifier: Unlicense
 */

/* hac 14.61, pp608 */
int 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;
   }

#ifdef BN_FAST_MP_INVMOD_C
   /* if the modulus is odd we can use a faster routine instead */
   if ((mp_isodd(b) == MP_YES)) {
      return fast_mp_invmod(a, b, c);
   }
#endif

#ifdef BN_MP_INVMOD_SLOW_C
   return mp_invmod_slow(a, b, c);
#else
   return MP_VAL;
#endif
}
#endif

/* ref:         HEAD -> master, tag: v1.1.0 */
/* git commit:  08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
/* commit time: 2019-01-28 20:32:32 +0100 */