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-rw-r--r--pwmanager/libcrypt/mpi/mpi-bit.c257
1 files changed, 257 insertions, 0 deletions
diff --git a/pwmanager/libcrypt/mpi/mpi-bit.c b/pwmanager/libcrypt/mpi/mpi-bit.c
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+++ b/pwmanager/libcrypt/mpi/mpi-bit.c
@@ -0,0 +1,257 @@
+/* mpi-bit.c - MPI bit level fucntions
+ * Copyright (C) 1998, 1999, 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
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+#include "mpi-internal.h"
+#include "longlong.h"
+
+
+#ifdef MPI_INTERNAL_NEED_CLZ_TAB
+#ifdef __STDC__
+const
+#endif
+unsigned char
+_gcry_clz_tab[] =
+{
+ 0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
+ 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+ 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+ 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+ 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+};
+#endif
+
+
+#define A_LIMB_1 ((mpi_limb_t)1)
+
+
+/****************
+ * Sometimes we have MSL (most significant limbs) which are 0;
+ * this is for some reasons not good, so this function removes them.
+ */
+void
+_gcry_mpi_normalize( gcry_mpi_t a )
+{
+ if( mpi_is_opaque(a) )
+ return;
+
+ for( ; a->nlimbs && !a->d[a->nlimbs-1]; a->nlimbs-- )
+ ;
+}
+
+
+
+/****************
+ * Return the number of bits in A.
+ */
+unsigned int
+gcry_mpi_get_nbits( gcry_mpi_t a )
+{
+ unsigned n;
+
+ if( mpi_is_opaque(a) ) {
+ return a->sign; /* which holds the number of bits */
+ }
+
+ _gcry_mpi_normalize( a );
+ if( a->nlimbs ) {
+ mpi_limb_t alimb = a->d[a->nlimbs-1];
+ if( alimb )
+ count_leading_zeros( n, alimb );
+ else
+ n = BITS_PER_MPI_LIMB;
+ n = BITS_PER_MPI_LIMB - n + (a->nlimbs-1) * BITS_PER_MPI_LIMB;
+ }
+ else
+ n = 0;
+ return n;
+}
+
+
+/****************
+ * Test whether bit N is set.
+ */
+int
+gcry_mpi_test_bit( gcry_mpi_t a, unsigned int n )
+{
+ unsigned int limbno, bitno;
+ mpi_limb_t limb;
+
+ limbno = n / BITS_PER_MPI_LIMB;
+ bitno = n % BITS_PER_MPI_LIMB;
+
+ if( limbno >= a->nlimbs )
+ return 0; /* too far left: this is a 0 */
+ limb = a->d[limbno];
+ return (limb & (A_LIMB_1 << bitno))? 1: 0;
+}
+
+
+/****************
+ * Set bit N of A.
+ */
+void
+gcry_mpi_set_bit( gcry_mpi_t a, unsigned int n )
+{
+ unsigned int limbno, bitno;
+
+ limbno = n / BITS_PER_MPI_LIMB;
+ bitno = n % BITS_PER_MPI_LIMB;
+
+ if( limbno >= a->nlimbs ) { /* resize */
+ if( a->alloced >= limbno )
+ mpi_resize(a, limbno+1 );
+ a->nlimbs = limbno+1;
+ }
+ a->d[limbno] |= (A_LIMB_1<<bitno);
+}
+
+/****************
+ * Set bit N of A. and clear all bits above
+ */
+void
+gcry_mpi_set_highbit( gcry_mpi_t a, unsigned int n )
+{
+ unsigned int limbno, bitno;
+
+ limbno = n / BITS_PER_MPI_LIMB;
+ bitno = n % BITS_PER_MPI_LIMB;
+
+ if( limbno >= a->nlimbs ) { /* resize */
+ if( a->alloced >= limbno )
+ mpi_resize(a, limbno+1 );
+ a->nlimbs = limbno+1;
+ }
+ a->d[limbno] |= (A_LIMB_1<<bitno);
+ for( bitno++; bitno < BITS_PER_MPI_LIMB; bitno++ )
+ a->d[limbno] &= ~(A_LIMB_1 << bitno);
+ a->nlimbs = limbno+1;
+}
+
+/****************
+ * clear bit N of A and all bits above
+ */
+void
+gcry_mpi_clear_highbit( gcry_mpi_t a, unsigned int n )
+{
+ unsigned int limbno, bitno;
+
+ limbno = n / BITS_PER_MPI_LIMB;
+ bitno = n % BITS_PER_MPI_LIMB;
+
+ if( limbno >= a->nlimbs )
+ return; /* not allocated, so need to clear bits :-) */
+
+ for( ; bitno < BITS_PER_MPI_LIMB; bitno++ )
+ a->d[limbno] &= ~(A_LIMB_1 << bitno);
+ a->nlimbs = limbno+1;
+}
+
+/****************
+ * Clear bit N of A.
+ */
+void
+gcry_mpi_clear_bit( gcry_mpi_t a, unsigned int n )
+{
+ unsigned int limbno, bitno;
+
+ limbno = n / BITS_PER_MPI_LIMB;
+ bitno = n % BITS_PER_MPI_LIMB;
+
+ if( limbno >= a->nlimbs )
+ return; /* don't need to clear this bit, it's to far to left */
+ a->d[limbno] &= ~(A_LIMB_1 << bitno);
+}
+
+
+/****************
+ * Shift A by N bits to the right
+ * FIXME: should use alloc_limb if X and A are same.
+ */
+void
+gcry_mpi_rshift( gcry_mpi_t x, gcry_mpi_t a, unsigned n )
+{
+ mpi_ptr_t xp;
+ mpi_size_t xsize;
+
+ xsize = a->nlimbs;
+ x->sign = a->sign;
+ RESIZE_IF_NEEDED(x, xsize);
+ xp = x->d;
+
+ if( xsize ) {
+ _gcry_mpih_rshift( xp, a->d, xsize, n);
+ MPN_NORMALIZE( xp, xsize);
+ }
+ x->nlimbs = xsize;
+}
+
+
+/****************
+ * Shift A by COUNT limbs to the left
+ * This is used only within the MPI library
+ */
+void
+_gcry_mpi_lshift_limbs( gcry_mpi_t a, unsigned int count )
+{
+ mpi_ptr_t ap = a->d;
+ int n = a->nlimbs;
+ int i;
+
+ if( !count || !n )
+ return;
+
+ RESIZE_IF_NEEDED( a, n+count );
+
+ for( i = n-1; i >= 0; i-- )
+ ap[i+count] = ap[i];
+ for(i=0; i < count; i++ )
+ ap[i] = 0;
+ a->nlimbs += count;
+}
+
+
+/****************
+ * Shift A by COUNT limbs to the right
+ * This is used only within the MPI library
+ */
+void
+_gcry_mpi_rshift_limbs( gcry_mpi_t a, unsigned int count )
+{
+ mpi_ptr_t ap = a->d;
+ mpi_size_t n = a->nlimbs;
+ unsigned int i;
+
+ if( count >= n ) {
+ a->nlimbs = 0;
+ return;
+ }
+
+ for( i = 0; i < n - count; i++ )
+ ap[i] = ap[i+count];
+ ap[i] = 0;
+ a->nlimbs -= count;
+}