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view libtommath/bn_mp_invmod.c @ 1885:5d8dbb6fdab7

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Fix SSH_PUBKEYINFO, limit characters, add tests We fix a bad_bufptr() failure from a previous commit. We now limit the allowed characters to those that will definitely be safe in a shell. Some scripts/programs may use arbitrary environment variables without escaping correctly - that could be a problem in a restricted environment. The current allowed set is a-z A-Z 0-9 .,_-+@ This also adds a test for SSH_PUBKEYINFO, by default it only runs under github actions (or "act -j build").
author Matt Johnston <matt@ucc.asn.au>
date Wed, 16 Mar 2022 17:17:23 +0800
parents 1051e4eea25a
children
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#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