view libtommath/bn_mp_and.c @ 296:6b41e2cbf071 dbclient-netcat-alike

A hack to make dbclient to tcp forwarding netcat style. eg ./dbclient -i testkey -L 1234:remotehost:remoteport tunnelhost will ssh to tunnelhost (using testkey, there's no way to ask for a password) and then tcpfwd to remotehost:remoteport on stdin/stdout. There's no way to give a cmdline password, so -i for a keyfile will have to do. Yet another reason for agent forwarding. The 1234 is a dummy var, I think it has to be a valid portnumber though.
author Matt Johnston <matt@ucc.asn.au>
date Tue, 21 Mar 2006 16:16:41 +0000
parents eed26cff980b
children 5ff8218bcee9
line wrap: on
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#include <tommath.h>
#ifdef BN_MP_AND_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
 */

/* AND two ints together */
int
mp_and (mp_int * a, mp_int * b, mp_int * c)
{
  int     res, ix, px;
  mp_int  t, *x;

  if (a->used > b->used) {
    if ((res = mp_init_copy (&t, a)) != MP_OKAY) {
      return res;
    }
    px = b->used;
    x = b;
  } else {
    if ((res = mp_init_copy (&t, b)) != MP_OKAY) {
      return res;
    }
    px = a->used;
    x = a;
  }

  for (ix = 0; ix < px; ix++) {
    t.dp[ix] &= x->dp[ix];
  }

  /* zero digits above the last from the smallest mp_int */
  for (; ix < t.used; ix++) {
    t.dp[ix] = 0;
  }

  mp_clamp (&t);
  mp_exch (c, &t);
  mp_clear (&t);
  return MP_OKAY;
}
#endif