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author | Dmitry Kasatkin <dmitry.kasatkin@intel.com> | 2011-11-07 13:16:37 (GMT) |
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committer | Dmitry Kasatkin <dmitry.kasatkin@intel.com> | 2011-11-09 09:47:26 (GMT) |
commit | 7e8dec918ef8e0f68b4937c3c50fa57002077a4d (patch) | |
tree | a17d33fa54fcb18c335b36c4550b889b206015f4 /lib/mpi/mpi-cmp.c | |
parent | d9c46b184fcfd33c85a7dc48a653435a08e21f56 (diff) | |
download | linux-fsl-qoriq-7e8dec918ef8e0f68b4937c3c50fa57002077a4d.tar.xz |
crypto: GnuPG based MPI lib - additional sources (part 4)
Adds the multi-precision-integer maths library which was originally taken
from GnuPG and ported to the kernel by (among others) David Howells.
This version is taken from Fedora kernel 2.6.32-71.14.1.el6.
The difference is that checkpatch reported errors and warnings have been fixed.
This library is used to implemenet RSA digital signature verification
used in IMA/EVM integrity protection subsystem.
Due to patch size limitation, the patch is divided into 4 parts.
This code is unnecessary for RSA digital signature verification,
but for completeness it is included here and can be compiled,
if CONFIG_MPILIB_EXTRA is enabled.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Diffstat (limited to 'lib/mpi/mpi-cmp.c')
-rw-r--r-- | lib/mpi/mpi-cmp.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/lib/mpi/mpi-cmp.c b/lib/mpi/mpi-cmp.c new file mode 100644 index 0000000..914bc42 --- /dev/null +++ b/lib/mpi/mpi-cmp.c @@ -0,0 +1,68 @@ +/* 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; +} + +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 (!cmp) + return 0; + if ((cmp < 0 ? 1 : 0) == (u->sign ? 1 : 0)) + return 1; + return -1; +} |