diff options
Diffstat (limited to 'lib/crypto/mpi/mpi-cmp.c')
| -rw-r--r-- | lib/crypto/mpi/mpi-cmp.c | 94 | 
1 files changed, 94 insertions, 0 deletions
| diff --git a/lib/crypto/mpi/mpi-cmp.c b/lib/crypto/mpi/mpi-cmp.c new file mode 100644 index 000000000000..c4cfa3ff0581 --- /dev/null +++ b/lib/crypto/mpi/mpi-cmp.c @@ -0,0 +1,94 @@ +/* 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 && !limb) +		return 0; +	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); + +static int do_mpi_cmp(MPI u, MPI v, int absmode) +{ +	mpi_size_t usize; +	mpi_size_t vsize; +	int usign; +	int vsign; +	int cmp; + +	mpi_normalize(u); +	mpi_normalize(v); + +	usize = u->nlimbs; +	vsize = v->nlimbs; +	usign = absmode ? 0 : u->sign; +	vsign = absmode ? 0 : v->sign; + +	/* Compare sign bits.  */ + +	if (!usign && vsign) +		return 1; +	if (usign && !vsign) +		return -1; + +	/* U and V are either both positive or both negative.  */ + +	if (usize != vsize && !usign && !vsign) +		return usize - vsize; +	if (usize != vsize && usign && vsign) +		return vsize + usize; +	if (!usize) +		return 0; +	cmp = mpihelp_cmp(u->d, v->d, usize); +	if (!cmp) +		return 0; +	if ((cmp < 0?1:0) == (usign?1:0)) +		return 1; + +	return -1; +} + +int mpi_cmp(MPI u, MPI v) +{ +	return do_mpi_cmp(u, v, 0); +} +EXPORT_SYMBOL_GPL(mpi_cmp); + +int mpi_cmpabs(MPI u, MPI v) +{ +	return do_mpi_cmp(u, v, 1); +} +EXPORT_SYMBOL_GPL(mpi_cmpabs); | 
