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view libtommath/bn_mp_invmod.c @ 340:454a34b2dfd1

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Fixes from Erik Hovland: cli-authpubkey.c: fix leak of keybuf cli-kex.c: fix leak of fingerprint fp cli-service.c: remove commented out code dropbearkey.c: don't attepmt to free NULL key on failure common-kex.c: only free key if it is initialised keyimport.c: remove dead encrypted-key code don't leak a FILE* loading OpenSSH keys rsa.c, dss.c: check return values for some libtommath functions svr-kex.c: check return value retrieving DH kex mpint svr-tcpfwd.c: fix null-dereference if remote tcp forward request fails tcp-accept.c: don't incorrectly free the tcpinfo var
author Matt Johnston <matt@ucc.asn.au>
date Fri, 07 Jul 2006 09:17:18 +0000
parents eed26cff980b
children 5ff8218bcee9
line wrap: on
line source

#include <tommath.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.
 *
 * The library is free for all purposes without any express
 * guarantee it works.
 *
 * Tom St Denis, [email protected], http://math.libtomcrypt.org
 */

/* hac 14.61, pp608 */
int mp_invmod (mp_int * a, mp_int * b, mp_int * c)
{
  /* b cannot be negative */
  if (b->sign == MP_NEG || mp_iszero(b) == 1) {
    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) == 1) {
    return fast_mp_invmod (a, b, c);
  }
#endif

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

  return MP_VAL;
}
#endif