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view libtommath/bn_mp_signed_rsh.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_SIGNED_RSH_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */

/* shift right by a certain bit count with sign extension */
mp_err mp_signed_rsh(const mp_int *a, int b, mp_int *c)
{
   mp_err res;
   if (a->sign == MP_ZPOS) {
      return mp_div_2d(a, b, c, NULL);
   }

   res = mp_add_d(a, 1uL, c);
   if (res != MP_OKAY) {
      return res;
   }

   res = mp_div_2d(c, b, c, NULL);
   return (res == MP_OKAY) ? mp_sub_d(c, 1uL, c) : res;
}
#endif