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Diffstat (limited to 'plugins/MirOTR/libgcrypt-1.4.6/mpi/mpi-mpow.c')
-rw-r--r--plugins/MirOTR/libgcrypt-1.4.6/mpi/mpi-mpow.c224
1 files changed, 0 insertions, 224 deletions
diff --git a/plugins/MirOTR/libgcrypt-1.4.6/mpi/mpi-mpow.c b/plugins/MirOTR/libgcrypt-1.4.6/mpi/mpi-mpow.c
deleted file mode 100644
index 131c5b67b2..0000000000
--- a/plugins/MirOTR/libgcrypt-1.4.6/mpi/mpi-mpow.c
+++ /dev/null
@@ -1,224 +0,0 @@
-/* mpi-mpow.c - MPI functions
- * Copyright (C) 1998, 1999, 2001, 2002, 2003 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
- */
-
-#include <config.h>
-#include <stdio.h>
-#include <stdlib.h>
-
-#include "mpi-internal.h"
-#include "longlong.h"
-#include "g10lib.h"
-
-
-/* Barrett is slower than the classical way. It can be tweaked by
- * using partial multiplications
- */
-/*#define USE_BARRETT*/
-
-
-
-#ifdef USE_BARRETT
-static void barrett_mulm( gcry_mpi_t w, gcry_mpi_t u, gcry_mpi_t v, gcry_mpi_t m, gcry_mpi_t y, int k, gcry_mpi_t r1, gcry_mpi_t r2 );
-static gcry_mpi_t init_barrett( gcry_mpi_t m, int *k, gcry_mpi_t *r1, gcry_mpi_t *r2 );
-static int calc_barrett( gcry_mpi_t r, gcry_mpi_t x, gcry_mpi_t m, gcry_mpi_t y, int k, gcry_mpi_t r1, gcry_mpi_t r2 );
-#else
-#define barrett_mulm( w, u, v, m, y, k, r1, r2 ) gcry_mpi_mulm( (w), (u), (v), (m) )
-#endif
-
-
-static int
-build_index( gcry_mpi_t *exparray, int k, int i, int t )
-{
- int j, bitno;
- int idx = 0;
-
- bitno = t-i;
- for(j=k-1; j >= 0; j-- ) {
- idx <<= 1;
- if( mpi_test_bit( exparray[j], bitno ) )
- idx |= 1;
- }
- /*log_debug("t=%d i=%d idx=%d\n", t, i, idx );*/
- return idx;
-}
-
-/****************
- * RES = (BASE[0] ^ EXP[0]) * (BASE[1] ^ EXP[1]) * ... * mod M
- */
-void
-_gcry_mpi_mulpowm( gcry_mpi_t res, gcry_mpi_t *basearray, gcry_mpi_t *exparray, gcry_mpi_t m)
-{
- int k; /* number of elements */
- int t; /* bit size of largest exponent */
- int i, j, idx;
- gcry_mpi_t *G; /* table with precomputed values of size 2^k */
- gcry_mpi_t tmp;
-#ifdef USE_BARRETT
- gcry_mpi_t barrett_y, barrett_r1, barrett_r2;
- int barrett_k;
-#endif
-
- for(k=0; basearray[k]; k++ )
- ;
- gcry_assert(k);
- for(t=0, i=0; (tmp=exparray[i]); i++ ) {
- /*log_mpidump("exp: ", tmp );*/
- j = mpi_get_nbits(tmp);
- if( j > t )
- t = j;
- }
- /*log_mpidump("mod: ", m );*/
- gcry_assert (i==k);
- gcry_assert (t);
- gcry_assert (k < 10);
-
- G = gcry_xcalloc( (1<<k) , sizeof *G );
-#ifdef USE_BARRETT
- barrett_y = init_barrett( m, &barrett_k, &barrett_r1, &barrett_r2 );
-#endif
- /* and calculate */
- tmp = mpi_alloc( mpi_get_nlimbs(m)+1 );
- mpi_set_ui( res, 1 );
- for(i = 1; i <= t; i++ ) {
- barrett_mulm(tmp, res, res, m, barrett_y, barrett_k,
- barrett_r1, barrett_r2 );
- idx = build_index( exparray, k, i, t );
- gcry_assert (idx >= 0 && idx < (1<<k));
- if( !G[idx] ) {
- if( !idx )
- G[0] = mpi_alloc_set_ui( 1 );
- else {
- for(j=0; j < k; j++ ) {
- if( (idx & (1<<j) ) ) {
- if( !G[idx] )
- G[idx] = mpi_copy( basearray[j] );
- else
- barrett_mulm( G[idx], G[idx], basearray[j],
- m, barrett_y, barrett_k, barrett_r1, barrett_r2 );
- }
- }
- if( !G[idx] )
- G[idx] = mpi_alloc(0);
- }
- }
- barrett_mulm(res, tmp, G[idx], m, barrett_y, barrett_k, barrett_r1, barrett_r2 );
- }
-
- /* cleanup */
- mpi_free(tmp);
-#ifdef USE_BARRETT
- mpi_free(barrett_y);
- mpi_free(barrett_r1);
- mpi_free(barrett_r2);
-#endif
- for(i=0; i < (1<<k); i++ )
- mpi_free(G[i]);
- gcry_free(G);
-}
-
-
-
-#ifdef USE_BARRETT
-static void
-barrett_mulm( gcry_mpi_t w, gcry_mpi_t u, gcry_mpi_t v, gcry_mpi_t m, gcry_mpi_t y, int k, gcry_mpi_t r1, gcry_mpi_t r2 )
-{
- mpi_mul(w, u, v);
- if( calc_barrett( w, w, m, y, k, r1, r2 ) )
- mpi_fdiv_r( w, w, m );
-}
-
-/****************
- * Barrett precalculation: y = floor(b^(2k) / m)
- */
-static gcry_mpi_t
-init_barrett( gcry_mpi_t m, int *k, gcry_mpi_t *r1, gcry_mpi_t *r2 )
-{
- gcry_mpi_t tmp;
-
- mpi_normalize( m );
- *k = mpi_get_nlimbs( m );
- tmp = mpi_alloc( *k + 1 );
- mpi_set_ui( tmp, 1 );
- mpi_lshift_limbs( tmp, 2 * *k );
- mpi_fdiv_q( tmp, tmp, m );
- *r1 = mpi_alloc( 2* *k + 1 );
- *r2 = mpi_alloc( 2* *k + 1 );
- return tmp;
-}
-
-/****************
- * Barrett reduction: We assume that these conditions are met:
- * Given x =(x_2k-1 ...x_0)_b
- * m =(m_k-1 ....m_0)_b with m_k-1 != 0
- * Output r = x mod m
- * Before using this function init_barret must be used to calucalte y and k.
- * Returns: false = no error
- * true = can't perform barret reduction
- */
-static int
-calc_barrett( gcry_mpi_t r, gcry_mpi_t x, gcry_mpi_t m, gcry_mpi_t y, int k, gcry_mpi_t r1, gcry_mpi_t r2 )
-{
- int xx = k > 3 ? k-3:0;
-
- mpi_normalize( x );
- if( mpi_get_nlimbs(x) > 2*k )
- return 1; /* can't do it */
-
- /* 1. q1 = floor( x / b^k-1)
- * q2 = q1 * y
- * q3 = floor( q2 / b^k+1 )
- * Actually, we don't need qx, we can work direct on r2
- */
- mpi_set( r2, x );
- mpi_rshift_limbs( r2, k-1 );
- mpi_mul( r2, r2, y );
- mpi_rshift_limbs( r2, k+1 );
-
- /* 2. r1 = x mod b^k+1
- * r2 = q3 * m mod b^k+1
- * r = r1 - r2
- * 3. if r < 0 then r = r + b^k+1
- */
- mpi_set( r1, x );
- if( r1->nlimbs > k+1 ) /* quick modulo operation */
- r1->nlimbs = k+1;
- mpi_mul( r2, r2, m );
- if( r2->nlimbs > k+1 ) /* quick modulo operation */
- r2->nlimbs = k+1;
- mpi_sub( r, r1, r2 );
-
- if( mpi_is_neg( r ) ) {
- gcry_mpi_t tmp;
-
- tmp = mpi_alloc( k + 2 );
- mpi_set_ui( tmp, 1 );
- mpi_lshift_limbs( tmp, k+1 );
- mpi_add( r, r, tmp );
- mpi_free(tmp);
- }
-
- /* 4. while r >= m do r = r - m */
- while( mpi_cmp( r, m ) >= 0 )
- mpi_sub( r, r, m );
-
- return 0;
-}
-#endif /* USE_BARRETT */
-
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