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linux/lib/crypto/mpi/mpi-cmp.c
Herbert Xu fca5cb4dd2 Revert "lib/mpi: Extend the MPI library"
This partially reverts commit a8ea8bdd9d.

Most of it is no longer needed since sm2 has been removed.  However,
the following functions have been kept as they have developed other
uses:

mpi_copy

mpi_mod

mpi_test_bit
mpi_set_bit
mpi_rshift

mpi_add
mpi_sub
mpi_addm
mpi_subm

mpi_mul
mpi_mulm

mpi_tdiv_r
mpi_fdiv_r

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2024-08-17 13:55:50 +08:00

73 lines
1.7 KiB
C

/* mpi-cmp.c - MPI functions
* Copyright (C) 1998, 1999 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GnuPG is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#include "mpi-internal.h"
int mpi_cmp_ui(MPI u, unsigned long v)
{
mpi_limb_t limb = v;
mpi_normalize(u);
if (u->nlimbs == 0) {
if (v == 0)
return 0;
else
return -1;
}
if (u->sign)
return -1;
if (u->nlimbs > 1)
return 1;
if (u->d[0] == limb)
return 0;
else if (u->d[0] > limb)
return 1;
else
return -1;
}
EXPORT_SYMBOL_GPL(mpi_cmp_ui);
int mpi_cmp(MPI u, MPI v)
{
mpi_size_t usize, vsize;
int cmp;
mpi_normalize(u);
mpi_normalize(v);
usize = u->nlimbs;
vsize = v->nlimbs;
if (!u->sign && v->sign)
return 1;
if (u->sign && !v->sign)
return -1;
if (usize != vsize && !u->sign && !v->sign)
return usize - vsize;
if (usize != vsize && u->sign && v->sign)
return vsize - usize;
if (!usize)
return 0;
cmp = mpihelp_cmp(u->d, v->d, usize);
if (u->sign)
return -cmp;
return cmp;
}
EXPORT_SYMBOL_GPL(mpi_cmp);