cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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mpi-cmp.c (2049B)

      1/* mpi-cmp.c  -  MPI functions
      2 * Copyright (C) 1998, 1999 Free Software Foundation, Inc.
      3 *
      4 * This file is part of GnuPG.
      5 *
      6 * GnuPG is free software; you can redistribute it and/or modify
      7 * it under the terms of the GNU General Public License as published by
      8 * the Free Software Foundation; either version 2 of the License, or
      9 * (at your option) any later version.
     10 *
     11 * GnuPG is distributed in the hope that it will be useful,
     12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
     13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     14 * GNU General Public License for more details.
     15 *
     16 * You should have received a copy of the GNU General Public License
     17 * along with this program; if not, write to the Free Software
     18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
     19 */
     20
     21#include "mpi-internal.h"
     22
     23int mpi_cmp_ui(MPI u, unsigned long v)
     24{
     25	mpi_limb_t limb = v;
     26
     27	mpi_normalize(u);
     28	if (!u->nlimbs && !limb)
     29		return 0;
     30	if (u->sign)
     31		return -1;
     32	if (u->nlimbs > 1)
     33		return 1;
     34
     35	if (u->d[0] == limb)
     36		return 0;
     37	else if (u->d[0] > limb)
     38		return 1;
     39	else
     40		return -1;
     41}
     42EXPORT_SYMBOL_GPL(mpi_cmp_ui);
     43
     44static int do_mpi_cmp(MPI u, MPI v, int absmode)
     45{
     46	mpi_size_t usize;
     47	mpi_size_t vsize;
     48	int usign;
     49	int vsign;
     50	int cmp;
     51
     52	mpi_normalize(u);
     53	mpi_normalize(v);
     54
     55	usize = u->nlimbs;
     56	vsize = v->nlimbs;
     57	usign = absmode ? 0 : u->sign;
     58	vsign = absmode ? 0 : v->sign;
     59
     60	/* Compare sign bits.  */
     61
     62	if (!usign && vsign)
     63		return 1;
     64	if (usign && !vsign)
     65		return -1;
     66
     67	/* U and V are either both positive or both negative.  */
     68
     69	if (usize != vsize && !usign && !vsign)
     70		return usize - vsize;
     71	if (usize != vsize && usign && vsign)
     72		return vsize + usize;
     73	if (!usize)
     74		return 0;
     75	cmp = mpihelp_cmp(u->d, v->d, usize);
     76	if (!cmp)
     77		return 0;
     78	if ((cmp < 0?1:0) == (usign?1:0))
     79		return 1;
     80
     81	return -1;
     82}
     83
     84int mpi_cmp(MPI u, MPI v)
     85{
     86	return do_mpi_cmp(u, v, 0);
     87}
     88EXPORT_SYMBOL_GPL(mpi_cmp);
     89
     90int mpi_cmpabs(MPI u, MPI v)
     91{
     92	return do_mpi_cmp(u, v, 1);
     93}
     94EXPORT_SYMBOL_GPL(mpi_cmpabs);