diff options
Diffstat (limited to 'plugins/MirOTR/libgcrypt-1.4.6/mpi/generic/mpih-mul3.c')
-rw-r--r-- | plugins/MirOTR/libgcrypt-1.4.6/mpi/generic/mpih-mul3.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/plugins/MirOTR/libgcrypt-1.4.6/mpi/generic/mpih-mul3.c b/plugins/MirOTR/libgcrypt-1.4.6/mpi/generic/mpih-mul3.c new file mode 100644 index 0000000000..5e84f94f31 --- /dev/null +++ b/plugins/MirOTR/libgcrypt-1.4.6/mpi/generic/mpih-mul3.c @@ -0,0 +1,68 @@ +/* mpih-mul3.c - MPI helper functions + * Copyright (C) 1994, 1996, 1997, 1998, 2001, + * 2002 Free Software Foundation, Inc. + * + * This file is part of Libgcrypt. + * + * Libgcrypt is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation; either version 2.1 of + * the License, or (at your option) any later version. + * + * Libgcrypt 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 Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser 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 + * + * Note: This code is heavily based on the GNU MP Library. + * Actually it's the same code with only minor changes in the + * way the data is stored; this is to support the abstraction + * of an optional secure memory allocation which may be used + * to avoid revealing of sensitive data due to paging etc. + */ + +#include <config.h> +#include <stdio.h> +#include <stdlib.h> +#include "mpi-internal.h" +#include "longlong.h" + + +mpi_limb_t +_gcry_mpih_submul_1( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, + mpi_size_t s1_size, mpi_limb_t s2_limb) +{ + mpi_limb_t cy_limb; + mpi_size_t j; + mpi_limb_t prod_high, prod_low; + mpi_limb_t x; + + /* The loop counter and index J goes from -SIZE to -1. This way + * the loop becomes faster. */ + j = -s1_size; + res_ptr -= j; + s1_ptr -= j; + + cy_limb = 0; + do + { + umul_ppmm( prod_high, prod_low, s1_ptr[j], s2_limb); + + prod_low += cy_limb; + cy_limb = (prod_low < cy_limb?1:0) + prod_high; + + x = res_ptr[j]; + prod_low = x - prod_low; + cy_limb += prod_low > x?1:0; + res_ptr[j] = prod_low; + } + while( ++j ); + + return cy_limb; +} + + |