mirror of https://github.com/hak5/openwrt.git
2011 lines
41 KiB
C
2011 lines
41 KiB
C
/*
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* Multi-precision integer library
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*
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* Based on XySSL: Copyright (C) 2006-2008 Christophe Devine
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*
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* Copyright (C) 2009 Paul Bakker <polarssl_maintainer at polarssl dot org>
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*
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* * Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* * Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* * Neither the names of PolarSSL or XySSL nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
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* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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/*
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* This MPI implementation is based on:
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*
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* http://www.cacr.math.uwaterloo.ca/hac/about/chap14.pdf
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* http://www.stillhq.com/extracted/gnupg-api/mpi/
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* http://math.libtomcrypt.com/files/tommath.pdf
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*/
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#include "polarssl/config.h"
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#if defined(POLARSSL_BIGNUM_C)
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#include "polarssl/bignum.h"
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#include "polarssl/bn_mul.h"
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#include <string.h>
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#include <stdlib.h>
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#include <stdarg.h>
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#define ciL ((int) sizeof(t_int)) /* chars in limb */
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#define biL (ciL << 3) /* bits in limb */
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#define biH (ciL << 2) /* half limb size */
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/*
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* Convert between bits/chars and number of limbs
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*/
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#define BITS_TO_LIMBS(i) (((i) + biL - 1) / biL)
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#define CHARS_TO_LIMBS(i) (((i) + ciL - 1) / ciL)
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/*
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* Initialize one or more mpi
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*/
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void mpi_init( mpi *X, ... )
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{
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va_list args;
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va_start( args, X );
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while( X != NULL )
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{
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X->s = 1;
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X->n = 0;
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X->p = NULL;
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X = va_arg( args, mpi* );
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}
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va_end( args );
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}
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/*
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* Unallocate one or more mpi
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*/
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void mpi_free( mpi *X, ... )
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{
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va_list args;
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va_start( args, X );
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while( X != NULL )
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{
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if( X->p != NULL )
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{
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memset( X->p, 0, X->n * ciL );
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free( X->p );
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}
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X->s = 1;
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X->n = 0;
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X->p = NULL;
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X = va_arg( args, mpi* );
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}
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va_end( args );
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}
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/*
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* Enlarge to the specified number of limbs
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*/
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int mpi_grow( mpi *X, int nblimbs )
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{
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t_int *p;
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if( X->n < nblimbs )
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{
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if( ( p = (t_int *) malloc( nblimbs * ciL ) ) == NULL )
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return( 1 );
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memset( p, 0, nblimbs * ciL );
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if( X->p != NULL )
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{
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memcpy( p, X->p, X->n * ciL );
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memset( X->p, 0, X->n * ciL );
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free( X->p );
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}
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X->n = nblimbs;
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X->p = p;
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}
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return( 0 );
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}
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/*
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* Copy the contents of Y into X
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*/
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int mpi_copy( mpi *X, mpi *Y )
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{
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int ret, i;
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if( X == Y )
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return( 0 );
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for( i = Y->n - 1; i > 0; i-- )
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if( Y->p[i] != 0 )
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break;
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i++;
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X->s = Y->s;
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MPI_CHK( mpi_grow( X, i ) );
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memset( X->p, 0, X->n * ciL );
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memcpy( X->p, Y->p, i * ciL );
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cleanup:
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return( ret );
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}
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/*
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* Swap the contents of X and Y
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*/
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void mpi_swap( mpi *X, mpi *Y )
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{
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mpi T;
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memcpy( &T, X, sizeof( mpi ) );
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memcpy( X, Y, sizeof( mpi ) );
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memcpy( Y, &T, sizeof( mpi ) );
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}
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/*
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* Set value from integer
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*/
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int mpi_lset( mpi *X, int z )
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{
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int ret;
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MPI_CHK( mpi_grow( X, 1 ) );
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memset( X->p, 0, X->n * ciL );
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X->p[0] = ( z < 0 ) ? -z : z;
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X->s = ( z < 0 ) ? -1 : 1;
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cleanup:
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return( ret );
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}
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/*
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* Return the number of least significant bits
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*/
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int mpi_lsb( mpi *X )
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{
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int i, j, count = 0;
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for( i = 0; i < X->n; i++ )
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for( j = 0; j < (int) biL; j++, count++ )
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if( ( ( X->p[i] >> j ) & 1 ) != 0 )
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return( count );
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return( 0 );
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}
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/*
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* Return the number of most significant bits
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*/
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int mpi_msb( mpi *X )
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{
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int i, j;
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for( i = X->n - 1; i > 0; i-- )
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if( X->p[i] != 0 )
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break;
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for( j = biL - 1; j >= 0; j-- )
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if( ( ( X->p[i] >> j ) & 1 ) != 0 )
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break;
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return( ( i * biL ) + j + 1 );
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}
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/*
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* Return the total size in bytes
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*/
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int mpi_size( mpi *X )
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{
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return( ( mpi_msb( X ) + 7 ) >> 3 );
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}
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/*
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* Convert an ASCII character to digit value
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*/
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static int mpi_get_digit( t_int *d, int radix, char c )
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{
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*d = 255;
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if( c >= 0x30 && c <= 0x39 ) *d = c - 0x30;
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if( c >= 0x41 && c <= 0x46 ) *d = c - 0x37;
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if( c >= 0x61 && c <= 0x66 ) *d = c - 0x57;
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if( *d >= (t_int) radix )
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return( POLARSSL_ERR_MPI_INVALID_CHARACTER );
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return( 0 );
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}
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/*
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* Import from an ASCII string
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*/
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int mpi_read_string( mpi *X, int radix, char *s )
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{
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int ret, i, j, n;
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t_int d;
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mpi T;
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if( radix < 2 || radix > 16 )
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return( POLARSSL_ERR_MPI_BAD_INPUT_DATA );
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mpi_init( &T, NULL );
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if( radix == 16 )
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{
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n = BITS_TO_LIMBS( strlen( s ) << 2 );
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MPI_CHK( mpi_grow( X, n ) );
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MPI_CHK( mpi_lset( X, 0 ) );
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for( i = strlen( s ) - 1, j = 0; i >= 0; i--, j++ )
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{
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if( i == 0 && s[i] == '-' )
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{
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X->s = -1;
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break;
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}
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MPI_CHK( mpi_get_digit( &d, radix, s[i] ) );
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X->p[j / (2 * ciL)] |= d << ( (j % (2 * ciL)) << 2 );
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}
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}
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else
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{
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MPI_CHK( mpi_lset( X, 0 ) );
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for( i = 0; i < (int) strlen( s ); i++ )
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{
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if( i == 0 && s[i] == '-' )
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{
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X->s = -1;
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continue;
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}
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MPI_CHK( mpi_get_digit( &d, radix, s[i] ) );
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MPI_CHK( mpi_mul_int( &T, X, radix ) );
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MPI_CHK( mpi_add_int( X, &T, d ) );
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}
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}
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cleanup:
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mpi_free( &T, NULL );
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return( ret );
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}
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/*
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* Helper to write the digits high-order first
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*/
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static int mpi_write_hlp( mpi *X, int radix, char **p )
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{
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int ret;
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t_int r;
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if( radix < 2 || radix > 16 )
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return( POLARSSL_ERR_MPI_BAD_INPUT_DATA );
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MPI_CHK( mpi_mod_int( &r, X, radix ) );
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MPI_CHK( mpi_div_int( X, NULL, X, radix ) );
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if( mpi_cmp_int( X, 0 ) != 0 )
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MPI_CHK( mpi_write_hlp( X, radix, p ) );
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if( r < 10 )
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*(*p)++ = (char)( r + 0x30 );
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else
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*(*p)++ = (char)( r + 0x37 );
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cleanup:
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return( ret );
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}
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/*
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* Export into an ASCII string
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*/
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int mpi_write_string( mpi *X, int radix, char *s, int *slen )
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{
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int ret = 0, n;
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char *p;
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mpi T;
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if( radix < 2 || radix > 16 )
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return( POLARSSL_ERR_MPI_BAD_INPUT_DATA );
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n = mpi_msb( X );
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if( radix >= 4 ) n >>= 1;
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if( radix >= 16 ) n >>= 1;
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n += 3;
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if( *slen < n )
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{
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*slen = n;
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return( POLARSSL_ERR_MPI_BUFFER_TOO_SMALL );
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}
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p = s;
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mpi_init( &T, NULL );
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if( X->s == -1 )
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*p++ = '-';
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if( radix == 16 )
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{
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int c, i, j, k;
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for( i = X->n - 1, k = 0; i >= 0; i-- )
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{
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for( j = ciL - 1; j >= 0; j-- )
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{
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c = ( X->p[i] >> (j << 3) ) & 0xFF;
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if( c == 0 && k == 0 && (i + j) != 0 )
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continue;
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p += sprintf( p, "%02X", c );
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k = 1;
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}
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}
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}
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else
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{
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MPI_CHK( mpi_copy( &T, X ) );
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MPI_CHK( mpi_write_hlp( &T, radix, &p ) );
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}
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*p++ = '\0';
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*slen = p - s;
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cleanup:
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mpi_free( &T, NULL );
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return( ret );
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}
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/*
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* Read X from an opened file
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*/
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int mpi_read_file( mpi *X, int radix, FILE *fin )
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{
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t_int d;
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int slen;
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char *p;
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char s[1024];
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memset( s, 0, sizeof( s ) );
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if( fgets( s, sizeof( s ) - 1, fin ) == NULL )
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return( POLARSSL_ERR_MPI_FILE_IO_ERROR );
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slen = strlen( s );
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if( s[slen - 1] == '\n' ) { slen--; s[slen] = '\0'; }
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if( s[slen - 1] == '\r' ) { slen--; s[slen] = '\0'; }
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p = s + slen;
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while( --p >= s )
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if( mpi_get_digit( &d, radix, *p ) != 0 )
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break;
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return( mpi_read_string( X, radix, p + 1 ) );
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}
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/*
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* Write X into an opened file (or stdout if fout == NULL)
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*/
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int mpi_write_file( char *p, mpi *X, int radix, FILE *fout )
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{
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int n, ret;
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size_t slen;
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size_t plen;
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char s[1024];
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n = sizeof( s );
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memset( s, 0, n );
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n -= 2;
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MPI_CHK( mpi_write_string( X, radix, s, (int *) &n ) );
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if( p == NULL ) p = "";
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plen = strlen( p );
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slen = strlen( s );
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s[slen++] = '\r';
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s[slen++] = '\n';
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if( fout != NULL )
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{
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if( fwrite( p, 1, plen, fout ) != plen ||
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fwrite( s, 1, slen, fout ) != slen )
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return( POLARSSL_ERR_MPI_FILE_IO_ERROR );
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}
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else
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printf( "%s%s", p, s );
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cleanup:
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return( ret );
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}
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/*
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* Import X from unsigned binary data, big endian
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*/
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int mpi_read_binary( mpi *X, unsigned char *buf, int buflen )
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{
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int ret, i, j, n;
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for( n = 0; n < buflen; n++ )
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if( buf[n] != 0 )
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break;
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MPI_CHK( mpi_grow( X, CHARS_TO_LIMBS( buflen - n ) ) );
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MPI_CHK( mpi_lset( X, 0 ) );
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for( i = buflen - 1, j = 0; i >= n; i--, j++ )
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X->p[j / ciL] |= ((t_int) buf[i]) << ((j % ciL) << 3);
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cleanup:
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return( ret );
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}
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/*
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* Export X into unsigned binary data, big endian
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*/
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int mpi_write_binary( mpi *X, unsigned char *buf, int buflen )
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{
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int i, j, n;
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n = mpi_size( X );
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if( buflen < n )
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return( POLARSSL_ERR_MPI_BUFFER_TOO_SMALL );
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memset( buf, 0, buflen );
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for( i = buflen - 1, j = 0; n > 0; i--, j++, n-- )
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buf[i] = (unsigned char)( X->p[j / ciL] >> ((j % ciL) << 3) );
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return( 0 );
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}
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/*
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* Left-shift: X <<= count
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*/
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int mpi_shift_l( mpi *X, int count )
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{
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int ret, i, v0, t1;
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t_int r0 = 0, r1;
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v0 = count / (biL );
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t1 = count & (biL - 1);
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i = mpi_msb( X ) + count;
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if( X->n * (int) biL < i )
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MPI_CHK( mpi_grow( X, BITS_TO_LIMBS( i ) ) );
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ret = 0;
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/*
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* shift by count / limb_size
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*/
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if( v0 > 0 )
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{
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for( i = X->n - 1; i >= v0; i-- )
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X->p[i] = X->p[i - v0];
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for( ; i >= 0; i-- )
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X->p[i] = 0;
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}
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/*
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* shift by count % limb_size
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*/
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if( t1 > 0 )
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{
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for( i = v0; i < X->n; i++ )
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{
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r1 = X->p[i] >> (biL - t1);
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X->p[i] <<= t1;
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X->p[i] |= r0;
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r0 = r1;
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}
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}
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cleanup:
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return( ret );
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}
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/*
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* Right-shift: X >>= count
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*/
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int mpi_shift_r( mpi *X, int count )
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{
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int i, v0, v1;
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t_int r0 = 0, r1;
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v0 = count / biL;
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v1 = count & (biL - 1);
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/*
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* shift by count / limb_size
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*/
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if( v0 > 0 )
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{
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for( i = 0; i < X->n - v0; i++ )
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|
X->p[i] = X->p[i + v0];
|
|
|
|
for( ; i < X->n; i++ )
|
|
X->p[i] = 0;
|
|
}
|
|
|
|
/*
|
|
* shift by count % limb_size
|
|
*/
|
|
if( v1 > 0 )
|
|
{
|
|
for( i = X->n - 1; i >= 0; i-- )
|
|
{
|
|
r1 = X->p[i] << (biL - v1);
|
|
X->p[i] >>= v1;
|
|
X->p[i] |= r0;
|
|
r0 = r1;
|
|
}
|
|
}
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
/*
|
|
* Compare unsigned values
|
|
*/
|
|
int mpi_cmp_abs( mpi *X, mpi *Y )
|
|
{
|
|
int i, j;
|
|
|
|
for( i = X->n - 1; i >= 0; i-- )
|
|
if( X->p[i] != 0 )
|
|
break;
|
|
|
|
for( j = Y->n - 1; j >= 0; j-- )
|
|
if( Y->p[j] != 0 )
|
|
break;
|
|
|
|
if( i < 0 && j < 0 )
|
|
return( 0 );
|
|
|
|
if( i > j ) return( 1 );
|
|
if( j > i ) return( -1 );
|
|
|
|
for( ; i >= 0; i-- )
|
|
{
|
|
if( X->p[i] > Y->p[i] ) return( 1 );
|
|
if( X->p[i] < Y->p[i] ) return( -1 );
|
|
}
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
/*
|
|
* Compare signed values
|
|
*/
|
|
int mpi_cmp_mpi( mpi *X, mpi *Y )
|
|
{
|
|
int i, j;
|
|
|
|
for( i = X->n - 1; i >= 0; i-- )
|
|
if( X->p[i] != 0 )
|
|
break;
|
|
|
|
for( j = Y->n - 1; j >= 0; j-- )
|
|
if( Y->p[j] != 0 )
|
|
break;
|
|
|
|
if( i < 0 && j < 0 )
|
|
return( 0 );
|
|
|
|
if( i > j ) return( X->s );
|
|
if( j > i ) return( -X->s );
|
|
|
|
if( X->s > 0 && Y->s < 0 ) return( 1 );
|
|
if( Y->s > 0 && X->s < 0 ) return( -1 );
|
|
|
|
for( ; i >= 0; i-- )
|
|
{
|
|
if( X->p[i] > Y->p[i] ) return( X->s );
|
|
if( X->p[i] < Y->p[i] ) return( -X->s );
|
|
}
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
/*
|
|
* Compare signed values
|
|
*/
|
|
int mpi_cmp_int( mpi *X, int z )
|
|
{
|
|
mpi Y;
|
|
t_int p[1];
|
|
|
|
*p = ( z < 0 ) ? -z : z;
|
|
Y.s = ( z < 0 ) ? -1 : 1;
|
|
Y.n = 1;
|
|
Y.p = p;
|
|
|
|
return( mpi_cmp_mpi( X, &Y ) );
|
|
}
|
|
|
|
/*
|
|
* Unsigned addition: X = |A| + |B| (HAC 14.7)
|
|
*/
|
|
int mpi_add_abs( mpi *X, mpi *A, mpi *B )
|
|
{
|
|
int ret, i, j;
|
|
t_int *o, *p, c;
|
|
|
|
if( X == B )
|
|
{
|
|
mpi *T = A; A = X; B = T;
|
|
}
|
|
|
|
if( X != A )
|
|
MPI_CHK( mpi_copy( X, A ) );
|
|
|
|
for( j = B->n - 1; j >= 0; j-- )
|
|
if( B->p[j] != 0 )
|
|
break;
|
|
|
|
MPI_CHK( mpi_grow( X, j + 1 ) );
|
|
|
|
o = B->p; p = X->p; c = 0;
|
|
|
|
for( i = 0; i <= j; i++, o++, p++ )
|
|
{
|
|
*p += c; c = ( *p < c );
|
|
*p += *o; c += ( *p < *o );
|
|
}
|
|
|
|
while( c != 0 )
|
|
{
|
|
if( i >= X->n )
|
|
{
|
|
MPI_CHK( mpi_grow( X, i + 1 ) );
|
|
p = X->p + i;
|
|
}
|
|
|
|
*p += c; c = ( *p < c ); i++;
|
|
}
|
|
|
|
cleanup:
|
|
|
|
return( ret );
|
|
}
|
|
|
|
/*
|
|
* Helper for mpi substraction
|
|
*/
|
|
static void mpi_sub_hlp( int n, t_int *s, t_int *d )
|
|
{
|
|
int i;
|
|
t_int c, z;
|
|
|
|
for( i = c = 0; i < n; i++, s++, d++ )
|
|
{
|
|
z = ( *d < c ); *d -= c;
|
|
c = ( *d < *s ) + z; *d -= *s;
|
|
}
|
|
|
|
while( c != 0 )
|
|
{
|
|
z = ( *d < c ); *d -= c;
|
|
c = z; i++; d++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Unsigned substraction: X = |A| - |B| (HAC 14.9)
|
|
*/
|
|
int mpi_sub_abs( mpi *X, mpi *A, mpi *B )
|
|
{
|
|
mpi TB;
|
|
int ret, n;
|
|
|
|
if( mpi_cmp_abs( A, B ) < 0 )
|
|
return( POLARSSL_ERR_MPI_NEGATIVE_VALUE );
|
|
|
|
mpi_init( &TB, NULL );
|
|
|
|
if( X == B )
|
|
{
|
|
MPI_CHK( mpi_copy( &TB, B ) );
|
|
B = &TB;
|
|
}
|
|
|
|
if( X != A )
|
|
MPI_CHK( mpi_copy( X, A ) );
|
|
|
|
ret = 0;
|
|
|
|
for( n = B->n - 1; n >= 0; n-- )
|
|
if( B->p[n] != 0 )
|
|
break;
|
|
|
|
mpi_sub_hlp( n + 1, B->p, X->p );
|
|
|
|
cleanup:
|
|
|
|
mpi_free( &TB, NULL );
|
|
|
|
return( ret );
|
|
}
|
|
|
|
/*
|
|
* Signed addition: X = A + B
|
|
*/
|
|
int mpi_add_mpi( mpi *X, mpi *A, mpi *B )
|
|
{
|
|
int ret, s = A->s;
|
|
|
|
if( A->s * B->s < 0 )
|
|
{
|
|
if( mpi_cmp_abs( A, B ) >= 0 )
|
|
{
|
|
MPI_CHK( mpi_sub_abs( X, A, B ) );
|
|
X->s = s;
|
|
}
|
|
else
|
|
{
|
|
MPI_CHK( mpi_sub_abs( X, B, A ) );
|
|
X->s = -s;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
MPI_CHK( mpi_add_abs( X, A, B ) );
|
|
X->s = s;
|
|
}
|
|
|
|
cleanup:
|
|
|
|
return( ret );
|
|
}
|
|
|
|
/*
|
|
* Signed substraction: X = A - B
|
|
*/
|
|
int mpi_sub_mpi( mpi *X, mpi *A, mpi *B )
|
|
{
|
|
int ret, s = A->s;
|
|
|
|
if( A->s * B->s > 0 )
|
|
{
|
|
if( mpi_cmp_abs( A, B ) >= 0 )
|
|
{
|
|
MPI_CHK( mpi_sub_abs( X, A, B ) );
|
|
X->s = s;
|
|
}
|
|
else
|
|
{
|
|
MPI_CHK( mpi_sub_abs( X, B, A ) );
|
|
X->s = -s;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
MPI_CHK( mpi_add_abs( X, A, B ) );
|
|
X->s = s;
|
|
}
|
|
|
|
cleanup:
|
|
|
|
return( ret );
|
|
}
|
|
|
|
/*
|
|
* Signed addition: X = A + b
|
|
*/
|
|
int mpi_add_int( mpi *X, mpi *A, int b )
|
|
{
|
|
mpi _B;
|
|
t_int p[1];
|
|
|
|
p[0] = ( b < 0 ) ? -b : b;
|
|
_B.s = ( b < 0 ) ? -1 : 1;
|
|
_B.n = 1;
|
|
_B.p = p;
|
|
|
|
return( mpi_add_mpi( X, A, &_B ) );
|
|
}
|
|
|
|
/*
|
|
* Signed substraction: X = A - b
|
|
*/
|
|
int mpi_sub_int( mpi *X, mpi *A, int b )
|
|
{
|
|
mpi _B;
|
|
t_int p[1];
|
|
|
|
p[0] = ( b < 0 ) ? -b : b;
|
|
_B.s = ( b < 0 ) ? -1 : 1;
|
|
_B.n = 1;
|
|
_B.p = p;
|
|
|
|
return( mpi_sub_mpi( X, A, &_B ) );
|
|
}
|
|
|
|
/*
|
|
* Helper for mpi multiplication
|
|
*/
|
|
static void mpi_mul_hlp( int i, t_int *s, t_int *d, t_int b )
|
|
{
|
|
t_int c = 0, t = 0;
|
|
|
|
#if defined(MULADDC_HUIT)
|
|
for( ; i >= 8; i -= 8 )
|
|
{
|
|
MULADDC_INIT
|
|
MULADDC_HUIT
|
|
MULADDC_STOP
|
|
}
|
|
|
|
for( ; i > 0; i-- )
|
|
{
|
|
MULADDC_INIT
|
|
MULADDC_CORE
|
|
MULADDC_STOP
|
|
}
|
|
#else
|
|
for( ; i >= 16; i -= 16 )
|
|
{
|
|
MULADDC_INIT
|
|
MULADDC_CORE MULADDC_CORE
|
|
MULADDC_CORE MULADDC_CORE
|
|
MULADDC_CORE MULADDC_CORE
|
|
MULADDC_CORE MULADDC_CORE
|
|
|
|
MULADDC_CORE MULADDC_CORE
|
|
MULADDC_CORE MULADDC_CORE
|
|
MULADDC_CORE MULADDC_CORE
|
|
MULADDC_CORE MULADDC_CORE
|
|
MULADDC_STOP
|
|
}
|
|
|
|
for( ; i >= 8; i -= 8 )
|
|
{
|
|
MULADDC_INIT
|
|
MULADDC_CORE MULADDC_CORE
|
|
MULADDC_CORE MULADDC_CORE
|
|
|
|
MULADDC_CORE MULADDC_CORE
|
|
MULADDC_CORE MULADDC_CORE
|
|
MULADDC_STOP
|
|
}
|
|
|
|
for( ; i > 0; i-- )
|
|
{
|
|
MULADDC_INIT
|
|
MULADDC_CORE
|
|
MULADDC_STOP
|
|
}
|
|
#endif
|
|
|
|
t++;
|
|
|
|
do {
|
|
*d += c; c = ( *d < c ); d++;
|
|
}
|
|
while( c != 0 );
|
|
}
|
|
|
|
/*
|
|
* Baseline multiplication: X = A * B (HAC 14.12)
|
|
*/
|
|
int mpi_mul_mpi( mpi *X, mpi *A, mpi *B )
|
|
{
|
|
int ret, i, j;
|
|
mpi TA, TB;
|
|
|
|
mpi_init( &TA, &TB, NULL );
|
|
|
|
if( X == A ) { MPI_CHK( mpi_copy( &TA, A ) ); A = &TA; }
|
|
if( X == B ) { MPI_CHK( mpi_copy( &TB, B ) ); B = &TB; }
|
|
|
|
for( i = A->n - 1; i >= 0; i-- )
|
|
if( A->p[i] != 0 )
|
|
break;
|
|
|
|
for( j = B->n - 1; j >= 0; j-- )
|
|
if( B->p[j] != 0 )
|
|
break;
|
|
|
|
MPI_CHK( mpi_grow( X, i + j + 2 ) );
|
|
MPI_CHK( mpi_lset( X, 0 ) );
|
|
|
|
for( i++; j >= 0; j-- )
|
|
mpi_mul_hlp( i, A->p, X->p + j, B->p[j] );
|
|
|
|
X->s = A->s * B->s;
|
|
|
|
cleanup:
|
|
|
|
mpi_free( &TB, &TA, NULL );
|
|
|
|
return( ret );
|
|
}
|
|
|
|
/*
|
|
* Baseline multiplication: X = A * b
|
|
*/
|
|
int mpi_mul_int( mpi *X, mpi *A, t_int b )
|
|
{
|
|
mpi _B;
|
|
t_int p[1];
|
|
|
|
_B.s = 1;
|
|
_B.n = 1;
|
|
_B.p = p;
|
|
p[0] = b;
|
|
|
|
return( mpi_mul_mpi( X, A, &_B ) );
|
|
}
|
|
|
|
/*
|
|
* Division by mpi: A = Q * B + R (HAC 14.20)
|
|
*/
|
|
int mpi_div_mpi( mpi *Q, mpi *R, mpi *A, mpi *B )
|
|
{
|
|
int ret, i, n, t, k;
|
|
mpi X, Y, Z, T1, T2;
|
|
|
|
if( mpi_cmp_int( B, 0 ) == 0 )
|
|
return( POLARSSL_ERR_MPI_DIVISION_BY_ZERO );
|
|
|
|
mpi_init( &X, &Y, &Z, &T1, &T2, NULL );
|
|
|
|
if( mpi_cmp_abs( A, B ) < 0 )
|
|
{
|
|
if( Q != NULL ) MPI_CHK( mpi_lset( Q, 0 ) );
|
|
if( R != NULL ) MPI_CHK( mpi_copy( R, A ) );
|
|
return( 0 );
|
|
}
|
|
|
|
MPI_CHK( mpi_copy( &X, A ) );
|
|
MPI_CHK( mpi_copy( &Y, B ) );
|
|
X.s = Y.s = 1;
|
|
|
|
MPI_CHK( mpi_grow( &Z, A->n + 2 ) );
|
|
MPI_CHK( mpi_lset( &Z, 0 ) );
|
|
MPI_CHK( mpi_grow( &T1, 2 ) );
|
|
MPI_CHK( mpi_grow( &T2, 3 ) );
|
|
|
|
k = mpi_msb( &Y ) % biL;
|
|
if( k < (int) biL - 1 )
|
|
{
|
|
k = biL - 1 - k;
|
|
MPI_CHK( mpi_shift_l( &X, k ) );
|
|
MPI_CHK( mpi_shift_l( &Y, k ) );
|
|
}
|
|
else k = 0;
|
|
|
|
n = X.n - 1;
|
|
t = Y.n - 1;
|
|
mpi_shift_l( &Y, biL * (n - t) );
|
|
|
|
while( mpi_cmp_mpi( &X, &Y ) >= 0 )
|
|
{
|
|
Z.p[n - t]++;
|
|
mpi_sub_mpi( &X, &X, &Y );
|
|
}
|
|
mpi_shift_r( &Y, biL * (n - t) );
|
|
|
|
for( i = n; i > t ; i-- )
|
|
{
|
|
if( X.p[i] >= Y.p[t] )
|
|
Z.p[i - t - 1] = ~0;
|
|
else
|
|
{
|
|
#if defined(POLARSSL_HAVE_LONGLONG)
|
|
t_dbl r;
|
|
|
|
r = (t_dbl) X.p[i] << biL;
|
|
r |= (t_dbl) X.p[i - 1];
|
|
r /= Y.p[t];
|
|
if( r > ((t_dbl) 1 << biL) - 1)
|
|
r = ((t_dbl) 1 << biL) - 1;
|
|
|
|
Z.p[i - t - 1] = (t_int) r;
|
|
#else
|
|
/*
|
|
* __udiv_qrnnd_c, from gmp/longlong.h
|
|
*/
|
|
t_int q0, q1, r0, r1;
|
|
t_int d0, d1, d, m;
|
|
|
|
d = Y.p[t];
|
|
d0 = ( d << biH ) >> biH;
|
|
d1 = ( d >> biH );
|
|
|
|
q1 = X.p[i] / d1;
|
|
r1 = X.p[i] - d1 * q1;
|
|
r1 <<= biH;
|
|
r1 |= ( X.p[i - 1] >> biH );
|
|
|
|
m = q1 * d0;
|
|
if( r1 < m )
|
|
{
|
|
q1--, r1 += d;
|
|
while( r1 >= d && r1 < m )
|
|
q1--, r1 += d;
|
|
}
|
|
r1 -= m;
|
|
|
|
q0 = r1 / d1;
|
|
r0 = r1 - d1 * q0;
|
|
r0 <<= biH;
|
|
r0 |= ( X.p[i - 1] << biH ) >> biH;
|
|
|
|
m = q0 * d0;
|
|
if( r0 < m )
|
|
{
|
|
q0--, r0 += d;
|
|
while( r0 >= d && r0 < m )
|
|
q0--, r0 += d;
|
|
}
|
|
r0 -= m;
|
|
|
|
Z.p[i - t - 1] = ( q1 << biH ) | q0;
|
|
#endif
|
|
}
|
|
|
|
Z.p[i - t - 1]++;
|
|
do
|
|
{
|
|
Z.p[i - t - 1]--;
|
|
|
|
MPI_CHK( mpi_lset( &T1, 0 ) );
|
|
T1.p[0] = (t < 1) ? 0 : Y.p[t - 1];
|
|
T1.p[1] = Y.p[t];
|
|
MPI_CHK( mpi_mul_int( &T1, &T1, Z.p[i - t - 1] ) );
|
|
|
|
MPI_CHK( mpi_lset( &T2, 0 ) );
|
|
T2.p[0] = (i < 2) ? 0 : X.p[i - 2];
|
|
T2.p[1] = (i < 1) ? 0 : X.p[i - 1];
|
|
T2.p[2] = X.p[i];
|
|
}
|
|
while( mpi_cmp_mpi( &T1, &T2 ) > 0 );
|
|
|
|
MPI_CHK( mpi_mul_int( &T1, &Y, Z.p[i - t - 1] ) );
|
|
MPI_CHK( mpi_shift_l( &T1, biL * (i - t - 1) ) );
|
|
MPI_CHK( mpi_sub_mpi( &X, &X, &T1 ) );
|
|
|
|
if( mpi_cmp_int( &X, 0 ) < 0 )
|
|
{
|
|
MPI_CHK( mpi_copy( &T1, &Y ) );
|
|
MPI_CHK( mpi_shift_l( &T1, biL * (i - t - 1) ) );
|
|
MPI_CHK( mpi_add_mpi( &X, &X, &T1 ) );
|
|
Z.p[i - t - 1]--;
|
|
}
|
|
}
|
|
|
|
if( Q != NULL )
|
|
{
|
|
mpi_copy( Q, &Z );
|
|
Q->s = A->s * B->s;
|
|
}
|
|
|
|
if( R != NULL )
|
|
{
|
|
mpi_shift_r( &X, k );
|
|
mpi_copy( R, &X );
|
|
|
|
R->s = A->s;
|
|
if( mpi_cmp_int( R, 0 ) == 0 )
|
|
R->s = 1;
|
|
}
|
|
|
|
cleanup:
|
|
|
|
mpi_free( &X, &Y, &Z, &T1, &T2, NULL );
|
|
|
|
return( ret );
|
|
}
|
|
|
|
/*
|
|
* Division by int: A = Q * b + R
|
|
*
|
|
* Returns 0 if successful
|
|
* 1 if memory allocation failed
|
|
* POLARSSL_ERR_MPI_DIVISION_BY_ZERO if b == 0
|
|
*/
|
|
int mpi_div_int( mpi *Q, mpi *R, mpi *A, int b )
|
|
{
|
|
mpi _B;
|
|
t_int p[1];
|
|
|
|
p[0] = ( b < 0 ) ? -b : b;
|
|
_B.s = ( b < 0 ) ? -1 : 1;
|
|
_B.n = 1;
|
|
_B.p = p;
|
|
|
|
return( mpi_div_mpi( Q, R, A, &_B ) );
|
|
}
|
|
|
|
/*
|
|
* Modulo: R = A mod B
|
|
*/
|
|
int mpi_mod_mpi( mpi *R, mpi *A, mpi *B )
|
|
{
|
|
int ret;
|
|
|
|
MPI_CHK( mpi_div_mpi( NULL, R, A, B ) );
|
|
|
|
while( mpi_cmp_int( R, 0 ) < 0 )
|
|
MPI_CHK( mpi_add_mpi( R, R, B ) );
|
|
|
|
while( mpi_cmp_mpi( R, B ) >= 0 )
|
|
MPI_CHK( mpi_sub_mpi( R, R, B ) );
|
|
|
|
cleanup:
|
|
|
|
return( ret );
|
|
}
|
|
|
|
/*
|
|
* Modulo: r = A mod b
|
|
*/
|
|
int mpi_mod_int( t_int *r, mpi *A, int b )
|
|
{
|
|
int i;
|
|
t_int x, y, z;
|
|
|
|
if( b == 0 )
|
|
return( POLARSSL_ERR_MPI_DIVISION_BY_ZERO );
|
|
|
|
if( b < 0 )
|
|
b = -b;
|
|
|
|
/*
|
|
* handle trivial cases
|
|
*/
|
|
if( b == 1 )
|
|
{
|
|
*r = 0;
|
|
return( 0 );
|
|
}
|
|
|
|
if( b == 2 )
|
|
{
|
|
*r = A->p[0] & 1;
|
|
return( 0 );
|
|
}
|
|
|
|
/*
|
|
* general case
|
|
*/
|
|
for( i = A->n - 1, y = 0; i >= 0; i-- )
|
|
{
|
|
x = A->p[i];
|
|
y = ( y << biH ) | ( x >> biH );
|
|
z = y / b;
|
|
y -= z * b;
|
|
|
|
x <<= biH;
|
|
y = ( y << biH ) | ( x >> biH );
|
|
z = y / b;
|
|
y -= z * b;
|
|
}
|
|
|
|
*r = y;
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
/*
|
|
* Fast Montgomery initialization (thanks to Tom St Denis)
|
|
*/
|
|
static void mpi_montg_init( t_int *mm, mpi *N )
|
|
{
|
|
t_int x, m0 = N->p[0];
|
|
|
|
x = m0;
|
|
x += ( ( m0 + 2 ) & 4 ) << 1;
|
|
x *= ( 2 - ( m0 * x ) );
|
|
|
|
if( biL >= 16 ) x *= ( 2 - ( m0 * x ) );
|
|
if( biL >= 32 ) x *= ( 2 - ( m0 * x ) );
|
|
if( biL >= 64 ) x *= ( 2 - ( m0 * x ) );
|
|
|
|
*mm = ~x + 1;
|
|
}
|
|
|
|
/*
|
|
* Montgomery multiplication: A = A * B * R^-1 mod N (HAC 14.36)
|
|
*/
|
|
static void mpi_montmul( mpi *A, mpi *B, mpi *N, t_int mm, mpi *T )
|
|
{
|
|
int i, n, m;
|
|
t_int u0, u1, *d;
|
|
|
|
memset( T->p, 0, T->n * ciL );
|
|
|
|
d = T->p;
|
|
n = N->n;
|
|
m = ( B->n < n ) ? B->n : n;
|
|
|
|
for( i = 0; i < n; i++ )
|
|
{
|
|
/*
|
|
* T = (T + u0*B + u1*N) / 2^biL
|
|
*/
|
|
u0 = A->p[i];
|
|
u1 = ( d[0] + u0 * B->p[0] ) * mm;
|
|
|
|
mpi_mul_hlp( m, B->p, d, u0 );
|
|
mpi_mul_hlp( n, N->p, d, u1 );
|
|
|
|
*d++ = u0; d[n + 1] = 0;
|
|
}
|
|
|
|
memcpy( A->p, d, (n + 1) * ciL );
|
|
|
|
if( mpi_cmp_abs( A, N ) >= 0 )
|
|
mpi_sub_hlp( n, N->p, A->p );
|
|
else
|
|
/* prevent timing attacks */
|
|
mpi_sub_hlp( n, A->p, T->p );
|
|
}
|
|
|
|
/*
|
|
* Montgomery reduction: A = A * R^-1 mod N
|
|
*/
|
|
static void mpi_montred( mpi *A, mpi *N, t_int mm, mpi *T )
|
|
{
|
|
t_int z = 1;
|
|
mpi U;
|
|
|
|
U.n = U.s = z;
|
|
U.p = &z;
|
|
|
|
mpi_montmul( A, &U, N, mm, T );
|
|
}
|
|
|
|
/*
|
|
* Sliding-window exponentiation: X = A^E mod N (HAC 14.85)
|
|
*/
|
|
int mpi_exp_mod( mpi *X, mpi *A, mpi *E, mpi *N, mpi *_RR )
|
|
{
|
|
int ret, i, j, wsize, wbits;
|
|
int bufsize, nblimbs, nbits;
|
|
t_int ei, mm, state;
|
|
mpi RR, T, W[64];
|
|
|
|
if( mpi_cmp_int( N, 0 ) < 0 || ( N->p[0] & 1 ) == 0 )
|
|
return( POLARSSL_ERR_MPI_BAD_INPUT_DATA );
|
|
|
|
/*
|
|
* Init temps and window size
|
|
*/
|
|
mpi_montg_init( &mm, N );
|
|
mpi_init( &RR, &T, NULL );
|
|
memset( W, 0, sizeof( W ) );
|
|
|
|
i = mpi_msb( E );
|
|
|
|
wsize = ( i > 671 ) ? 6 : ( i > 239 ) ? 5 :
|
|
( i > 79 ) ? 4 : ( i > 23 ) ? 3 : 1;
|
|
|
|
j = N->n + 1;
|
|
MPI_CHK( mpi_grow( X, j ) );
|
|
MPI_CHK( mpi_grow( &W[1], j ) );
|
|
MPI_CHK( mpi_grow( &T, j * 2 ) );
|
|
|
|
/*
|
|
* If 1st call, pre-compute R^2 mod N
|
|
*/
|
|
if( _RR == NULL || _RR->p == NULL )
|
|
{
|
|
MPI_CHK( mpi_lset( &RR, 1 ) );
|
|
MPI_CHK( mpi_shift_l( &RR, N->n * 2 * biL ) );
|
|
MPI_CHK( mpi_mod_mpi( &RR, &RR, N ) );
|
|
|
|
if( _RR != NULL )
|
|
memcpy( _RR, &RR, sizeof( mpi ) );
|
|
}
|
|
else
|
|
memcpy( &RR, _RR, sizeof( mpi ) );
|
|
|
|
/*
|
|
* W[1] = A * R^2 * R^-1 mod N = A * R mod N
|
|
*/
|
|
if( mpi_cmp_mpi( A, N ) >= 0 )
|
|
mpi_mod_mpi( &W[1], A, N );
|
|
else mpi_copy( &W[1], A );
|
|
|
|
mpi_montmul( &W[1], &RR, N, mm, &T );
|
|
|
|
/*
|
|
* X = R^2 * R^-1 mod N = R mod N
|
|
*/
|
|
MPI_CHK( mpi_copy( X, &RR ) );
|
|
mpi_montred( X, N, mm, &T );
|
|
|
|
if( wsize > 1 )
|
|
{
|
|
/*
|
|
* W[1 << (wsize - 1)] = W[1] ^ (wsize - 1)
|
|
*/
|
|
j = 1 << (wsize - 1);
|
|
|
|
MPI_CHK( mpi_grow( &W[j], N->n + 1 ) );
|
|
MPI_CHK( mpi_copy( &W[j], &W[1] ) );
|
|
|
|
for( i = 0; i < wsize - 1; i++ )
|
|
mpi_montmul( &W[j], &W[j], N, mm, &T );
|
|
|
|
/*
|
|
* W[i] = W[i - 1] * W[1]
|
|
*/
|
|
for( i = j + 1; i < (1 << wsize); i++ )
|
|
{
|
|
MPI_CHK( mpi_grow( &W[i], N->n + 1 ) );
|
|
MPI_CHK( mpi_copy( &W[i], &W[i - 1] ) );
|
|
|
|
mpi_montmul( &W[i], &W[1], N, mm, &T );
|
|
}
|
|
}
|
|
|
|
nblimbs = E->n;
|
|
bufsize = 0;
|
|
nbits = 0;
|
|
wbits = 0;
|
|
state = 0;
|
|
|
|
while( 1 )
|
|
{
|
|
if( bufsize == 0 )
|
|
{
|
|
if( nblimbs-- == 0 )
|
|
break;
|
|
|
|
bufsize = sizeof( t_int ) << 3;
|
|
}
|
|
|
|
bufsize--;
|
|
|
|
ei = (E->p[nblimbs] >> bufsize) & 1;
|
|
|
|
/*
|
|
* skip leading 0s
|
|
*/
|
|
if( ei == 0 && state == 0 )
|
|
continue;
|
|
|
|
if( ei == 0 && state == 1 )
|
|
{
|
|
/*
|
|
* out of window, square X
|
|
*/
|
|
mpi_montmul( X, X, N, mm, &T );
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* add ei to current window
|
|
*/
|
|
state = 2;
|
|
|
|
nbits++;
|
|
wbits |= (ei << (wsize - nbits));
|
|
|
|
if( nbits == wsize )
|
|
{
|
|
/*
|
|
* X = X^wsize R^-1 mod N
|
|
*/
|
|
for( i = 0; i < wsize; i++ )
|
|
mpi_montmul( X, X, N, mm, &T );
|
|
|
|
/*
|
|
* X = X * W[wbits] R^-1 mod N
|
|
*/
|
|
mpi_montmul( X, &W[wbits], N, mm, &T );
|
|
|
|
state--;
|
|
nbits = 0;
|
|
wbits = 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* process the remaining bits
|
|
*/
|
|
for( i = 0; i < nbits; i++ )
|
|
{
|
|
mpi_montmul( X, X, N, mm, &T );
|
|
|
|
wbits <<= 1;
|
|
|
|
if( (wbits & (1 << wsize)) != 0 )
|
|
mpi_montmul( X, &W[1], N, mm, &T );
|
|
}
|
|
|
|
/*
|
|
* X = A^E * R * R^-1 mod N = A^E mod N
|
|
*/
|
|
mpi_montred( X, N, mm, &T );
|
|
|
|
cleanup:
|
|
|
|
for( i = (1 << (wsize - 1)); i < (1 << wsize); i++ )
|
|
mpi_free( &W[i], NULL );
|
|
|
|
if( _RR != NULL )
|
|
mpi_free( &W[1], &T, NULL );
|
|
else mpi_free( &W[1], &T, &RR, NULL );
|
|
|
|
return( ret );
|
|
}
|
|
|
|
/*
|
|
* Greatest common divisor: G = gcd(A, B) (HAC 14.54)
|
|
*/
|
|
int mpi_gcd( mpi *G, mpi *A, mpi *B )
|
|
{
|
|
int ret, lz, lzt;
|
|
mpi TG, TA, TB;
|
|
|
|
mpi_init( &TG, &TA, &TB, NULL );
|
|
|
|
MPI_CHK( mpi_copy( &TA, A ) );
|
|
MPI_CHK( mpi_copy( &TB, B ) );
|
|
|
|
lz = mpi_lsb( &TA );
|
|
lzt = mpi_lsb( &TB );
|
|
|
|
if ( lzt < lz )
|
|
lz = lzt;
|
|
|
|
MPI_CHK( mpi_shift_r( &TA, lz ) );
|
|
MPI_CHK( mpi_shift_r( &TB, lz ) );
|
|
|
|
TA.s = TB.s = 1;
|
|
|
|
while( mpi_cmp_int( &TA, 0 ) != 0 )
|
|
{
|
|
MPI_CHK( mpi_shift_r( &TA, mpi_lsb( &TA ) ) );
|
|
MPI_CHK( mpi_shift_r( &TB, mpi_lsb( &TB ) ) );
|
|
|
|
if( mpi_cmp_mpi( &TA, &TB ) >= 0 )
|
|
{
|
|
MPI_CHK( mpi_sub_abs( &TA, &TA, &TB ) );
|
|
MPI_CHK( mpi_shift_r( &TA, 1 ) );
|
|
}
|
|
else
|
|
{
|
|
MPI_CHK( mpi_sub_abs( &TB, &TB, &TA ) );
|
|
MPI_CHK( mpi_shift_r( &TB, 1 ) );
|
|
}
|
|
}
|
|
|
|
MPI_CHK( mpi_shift_l( &TB, lz ) );
|
|
MPI_CHK( mpi_copy( G, &TB ) );
|
|
|
|
cleanup:
|
|
|
|
mpi_free( &TB, &TA, &TG, NULL );
|
|
|
|
return( ret );
|
|
}
|
|
|
|
#if defined(POLARSSL_GENPRIME)
|
|
|
|
/*
|
|
* Modular inverse: X = A^-1 mod N (HAC 14.61 / 14.64)
|
|
*/
|
|
int mpi_inv_mod( mpi *X, mpi *A, mpi *N )
|
|
{
|
|
int ret;
|
|
mpi G, TA, TU, U1, U2, TB, TV, V1, V2;
|
|
|
|
if( mpi_cmp_int( N, 0 ) <= 0 )
|
|
return( POLARSSL_ERR_MPI_BAD_INPUT_DATA );
|
|
|
|
mpi_init( &TA, &TU, &U1, &U2, &G,
|
|
&TB, &TV, &V1, &V2, NULL );
|
|
|
|
MPI_CHK( mpi_gcd( &G, A, N ) );
|
|
|
|
if( mpi_cmp_int( &G, 1 ) != 0 )
|
|
{
|
|
ret = POLARSSL_ERR_MPI_NOT_ACCEPTABLE;
|
|
goto cleanup;
|
|
}
|
|
|
|
MPI_CHK( mpi_mod_mpi( &TA, A, N ) );
|
|
MPI_CHK( mpi_copy( &TU, &TA ) );
|
|
MPI_CHK( mpi_copy( &TB, N ) );
|
|
MPI_CHK( mpi_copy( &TV, N ) );
|
|
|
|
MPI_CHK( mpi_lset( &U1, 1 ) );
|
|
MPI_CHK( mpi_lset( &U2, 0 ) );
|
|
MPI_CHK( mpi_lset( &V1, 0 ) );
|
|
MPI_CHK( mpi_lset( &V2, 1 ) );
|
|
|
|
do
|
|
{
|
|
while( ( TU.p[0] & 1 ) == 0 )
|
|
{
|
|
MPI_CHK( mpi_shift_r( &TU, 1 ) );
|
|
|
|
if( ( U1.p[0] & 1 ) != 0 || ( U2.p[0] & 1 ) != 0 )
|
|
{
|
|
MPI_CHK( mpi_add_mpi( &U1, &U1, &TB ) );
|
|
MPI_CHK( mpi_sub_mpi( &U2, &U2, &TA ) );
|
|
}
|
|
|
|
MPI_CHK( mpi_shift_r( &U1, 1 ) );
|
|
MPI_CHK( mpi_shift_r( &U2, 1 ) );
|
|
}
|
|
|
|
while( ( TV.p[0] & 1 ) == 0 )
|
|
{
|
|
MPI_CHK( mpi_shift_r( &TV, 1 ) );
|
|
|
|
if( ( V1.p[0] & 1 ) != 0 || ( V2.p[0] & 1 ) != 0 )
|
|
{
|
|
MPI_CHK( mpi_add_mpi( &V1, &V1, &TB ) );
|
|
MPI_CHK( mpi_sub_mpi( &V2, &V2, &TA ) );
|
|
}
|
|
|
|
MPI_CHK( mpi_shift_r( &V1, 1 ) );
|
|
MPI_CHK( mpi_shift_r( &V2, 1 ) );
|
|
}
|
|
|
|
if( mpi_cmp_mpi( &TU, &TV ) >= 0 )
|
|
{
|
|
MPI_CHK( mpi_sub_mpi( &TU, &TU, &TV ) );
|
|
MPI_CHK( mpi_sub_mpi( &U1, &U1, &V1 ) );
|
|
MPI_CHK( mpi_sub_mpi( &U2, &U2, &V2 ) );
|
|
}
|
|
else
|
|
{
|
|
MPI_CHK( mpi_sub_mpi( &TV, &TV, &TU ) );
|
|
MPI_CHK( mpi_sub_mpi( &V1, &V1, &U1 ) );
|
|
MPI_CHK( mpi_sub_mpi( &V2, &V2, &U2 ) );
|
|
}
|
|
}
|
|
while( mpi_cmp_int( &TU, 0 ) != 0 );
|
|
|
|
while( mpi_cmp_int( &V1, 0 ) < 0 )
|
|
MPI_CHK( mpi_add_mpi( &V1, &V1, N ) );
|
|
|
|
while( mpi_cmp_mpi( &V1, N ) >= 0 )
|
|
MPI_CHK( mpi_sub_mpi( &V1, &V1, N ) );
|
|
|
|
MPI_CHK( mpi_copy( X, &V1 ) );
|
|
|
|
cleanup:
|
|
|
|
mpi_free( &V2, &V1, &TV, &TB, &G,
|
|
&U2, &U1, &TU, &TA, NULL );
|
|
|
|
return( ret );
|
|
}
|
|
|
|
static const int small_prime[] =
|
|
{
|
|
3, 5, 7, 11, 13, 17, 19, 23,
|
|
29, 31, 37, 41, 43, 47, 53, 59,
|
|
61, 67, 71, 73, 79, 83, 89, 97,
|
|
101, 103, 107, 109, 113, 127, 131, 137,
|
|
139, 149, 151, 157, 163, 167, 173, 179,
|
|
181, 191, 193, 197, 199, 211, 223, 227,
|
|
229, 233, 239, 241, 251, 257, 263, 269,
|
|
271, 277, 281, 283, 293, 307, 311, 313,
|
|
317, 331, 337, 347, 349, 353, 359, 367,
|
|
373, 379, 383, 389, 397, 401, 409, 419,
|
|
421, 431, 433, 439, 443, 449, 457, 461,
|
|
463, 467, 479, 487, 491, 499, 503, 509,
|
|
521, 523, 541, 547, 557, 563, 569, 571,
|
|
577, 587, 593, 599, 601, 607, 613, 617,
|
|
619, 631, 641, 643, 647, 653, 659, 661,
|
|
673, 677, 683, 691, 701, 709, 719, 727,
|
|
733, 739, 743, 751, 757, 761, 769, 773,
|
|
787, 797, 809, 811, 821, 823, 827, 829,
|
|
839, 853, 857, 859, 863, 877, 881, 883,
|
|
887, 907, 911, 919, 929, 937, 941, 947,
|
|
953, 967, 971, 977, 983, 991, 997, -103
|
|
};
|
|
|
|
/*
|
|
* Miller-Rabin primality test (HAC 4.24)
|
|
*/
|
|
int mpi_is_prime( mpi *X, int (*f_rng)(void *), void *p_rng )
|
|
{
|
|
int ret, i, j, n, s, xs;
|
|
mpi W, R, T, A, RR;
|
|
unsigned char *p;
|
|
|
|
if( mpi_cmp_int( X, 0 ) == 0 )
|
|
return( 0 );
|
|
|
|
mpi_init( &W, &R, &T, &A, &RR, NULL );
|
|
|
|
xs = X->s; X->s = 1;
|
|
|
|
/*
|
|
* test trivial factors first
|
|
*/
|
|
if( ( X->p[0] & 1 ) == 0 )
|
|
return( POLARSSL_ERR_MPI_NOT_ACCEPTABLE );
|
|
|
|
for( i = 0; small_prime[i] > 0; i++ )
|
|
{
|
|
t_int r;
|
|
|
|
if( mpi_cmp_int( X, small_prime[i] ) <= 0 )
|
|
return( 0 );
|
|
|
|
MPI_CHK( mpi_mod_int( &r, X, small_prime[i] ) );
|
|
|
|
if( r == 0 )
|
|
return( POLARSSL_ERR_MPI_NOT_ACCEPTABLE );
|
|
}
|
|
|
|
/*
|
|
* W = |X| - 1
|
|
* R = W >> lsb( W )
|
|
*/
|
|
s = mpi_lsb( &W );
|
|
MPI_CHK( mpi_sub_int( &W, X, 1 ) );
|
|
MPI_CHK( mpi_copy( &R, &W ) );
|
|
MPI_CHK( mpi_shift_r( &R, s ) );
|
|
|
|
i = mpi_msb( X );
|
|
/*
|
|
* HAC, table 4.4
|
|
*/
|
|
n = ( ( i >= 1300 ) ? 2 : ( i >= 850 ) ? 3 :
|
|
( i >= 650 ) ? 4 : ( i >= 350 ) ? 8 :
|
|
( i >= 250 ) ? 12 : ( i >= 150 ) ? 18 : 27 );
|
|
|
|
for( i = 0; i < n; i++ )
|
|
{
|
|
/*
|
|
* pick a random A, 1 < A < |X| - 1
|
|
*/
|
|
MPI_CHK( mpi_grow( &A, X->n ) );
|
|
|
|
p = (unsigned char *) A.p;
|
|
for( j = 0; j < A.n * ciL; j++ )
|
|
*p++ = (unsigned char) f_rng( p_rng );
|
|
|
|
j = mpi_msb( &A ) - mpi_msb( &W );
|
|
MPI_CHK( mpi_shift_r( &A, j + 1 ) );
|
|
A.p[0] |= 3;
|
|
|
|
/*
|
|
* A = A^R mod |X|
|
|
*/
|
|
MPI_CHK( mpi_exp_mod( &A, &A, &R, X, &RR ) );
|
|
|
|
if( mpi_cmp_mpi( &A, &W ) == 0 ||
|
|
mpi_cmp_int( &A, 1 ) == 0 )
|
|
continue;
|
|
|
|
j = 1;
|
|
while( j < s && mpi_cmp_mpi( &A, &W ) != 0 )
|
|
{
|
|
/*
|
|
* A = A * A mod |X|
|
|
*/
|
|
MPI_CHK( mpi_mul_mpi( &T, &A, &A ) );
|
|
MPI_CHK( mpi_mod_mpi( &A, &T, X ) );
|
|
|
|
if( mpi_cmp_int( &A, 1 ) == 0 )
|
|
break;
|
|
|
|
j++;
|
|
}
|
|
|
|
/*
|
|
* not prime if A != |X| - 1 or A == 1
|
|
*/
|
|
if( mpi_cmp_mpi( &A, &W ) != 0 ||
|
|
mpi_cmp_int( &A, 1 ) == 0 )
|
|
{
|
|
ret = POLARSSL_ERR_MPI_NOT_ACCEPTABLE;
|
|
break;
|
|
}
|
|
}
|
|
|
|
cleanup:
|
|
|
|
X->s = xs;
|
|
|
|
mpi_free( &RR, &A, &T, &R, &W, NULL );
|
|
|
|
return( ret );
|
|
}
|
|
|
|
/*
|
|
* Prime number generation
|
|
*/
|
|
int mpi_gen_prime( mpi *X, int nbits, int dh_flag,
|
|
int (*f_rng)(void *), void *p_rng )
|
|
{
|
|
int ret, k, n;
|
|
unsigned char *p;
|
|
mpi Y;
|
|
|
|
if( nbits < 3 )
|
|
return( POLARSSL_ERR_MPI_BAD_INPUT_DATA );
|
|
|
|
mpi_init( &Y, NULL );
|
|
|
|
n = BITS_TO_LIMBS( nbits );
|
|
|
|
MPI_CHK( mpi_grow( X, n ) );
|
|
MPI_CHK( mpi_lset( X, 0 ) );
|
|
|
|
p = (unsigned char *) X->p;
|
|
for( k = 0; k < X->n * ciL; k++ )
|
|
*p++ = (unsigned char) f_rng( p_rng );
|
|
|
|
k = mpi_msb( X );
|
|
if( k < nbits ) MPI_CHK( mpi_shift_l( X, nbits - k ) );
|
|
if( k > nbits ) MPI_CHK( mpi_shift_r( X, k - nbits ) );
|
|
|
|
X->p[0] |= 3;
|
|
|
|
if( dh_flag == 0 )
|
|
{
|
|
while( ( ret = mpi_is_prime( X, f_rng, p_rng ) ) != 0 )
|
|
{
|
|
if( ret != POLARSSL_ERR_MPI_NOT_ACCEPTABLE )
|
|
goto cleanup;
|
|
|
|
MPI_CHK( mpi_add_int( X, X, 2 ) );
|
|
}
|
|
}
|
|
else
|
|
{
|
|
MPI_CHK( mpi_sub_int( &Y, X, 1 ) );
|
|
MPI_CHK( mpi_shift_r( &Y, 1 ) );
|
|
|
|
while( 1 )
|
|
{
|
|
if( ( ret = mpi_is_prime( X, f_rng, p_rng ) ) == 0 )
|
|
{
|
|
if( ( ret = mpi_is_prime( &Y, f_rng, p_rng ) ) == 0 )
|
|
break;
|
|
|
|
if( ret != POLARSSL_ERR_MPI_NOT_ACCEPTABLE )
|
|
goto cleanup;
|
|
}
|
|
|
|
if( ret != POLARSSL_ERR_MPI_NOT_ACCEPTABLE )
|
|
goto cleanup;
|
|
|
|
MPI_CHK( mpi_add_int( &Y, X, 1 ) );
|
|
MPI_CHK( mpi_add_int( X, X, 2 ) );
|
|
MPI_CHK( mpi_shift_r( &Y, 1 ) );
|
|
}
|
|
}
|
|
|
|
cleanup:
|
|
|
|
mpi_free( &Y, NULL );
|
|
|
|
return( ret );
|
|
}
|
|
|
|
#endif
|
|
|
|
#if defined(POLARSSL_SELF_TEST)
|
|
|
|
#define GCD_PAIR_COUNT 3
|
|
|
|
static const int gcd_pairs[GCD_PAIR_COUNT][3] =
|
|
{
|
|
{ 693, 609, 21 },
|
|
{ 1764, 868, 28 },
|
|
{ 768454923, 542167814, 1 }
|
|
};
|
|
|
|
/*
|
|
* Checkup routine
|
|
*/
|
|
int mpi_self_test( int verbose )
|
|
{
|
|
int ret, i;
|
|
mpi A, E, N, X, Y, U, V;
|
|
|
|
mpi_init( &A, &E, &N, &X, &Y, &U, &V, NULL );
|
|
|
|
MPI_CHK( mpi_read_string( &A, 16,
|
|
"EFE021C2645FD1DC586E69184AF4A31E" \
|
|
"D5F53E93B5F123FA41680867BA110131" \
|
|
"944FE7952E2517337780CB0DB80E61AA" \
|
|
"E7C8DDC6C5C6AADEB34EB38A2F40D5E6" ) );
|
|
|
|
MPI_CHK( mpi_read_string( &E, 16,
|
|
"B2E7EFD37075B9F03FF989C7C5051C20" \
|
|
"34D2A323810251127E7BF8625A4F49A5" \
|
|
"F3E27F4DA8BD59C47D6DAABA4C8127BD" \
|
|
"5B5C25763222FEFCCFC38B832366C29E" ) );
|
|
|
|
MPI_CHK( mpi_read_string( &N, 16,
|
|
"0066A198186C18C10B2F5ED9B522752A" \
|
|
"9830B69916E535C8F047518A889A43A5" \
|
|
"94B6BED27A168D31D4A52F88925AA8F5" ) );
|
|
|
|
MPI_CHK( mpi_mul_mpi( &X, &A, &N ) );
|
|
|
|
MPI_CHK( mpi_read_string( &U, 16,
|
|
"602AB7ECA597A3D6B56FF9829A5E8B85" \
|
|
"9E857EA95A03512E2BAE7391688D264A" \
|
|
"A5663B0341DB9CCFD2C4C5F421FEC814" \
|
|
"8001B72E848A38CAE1C65F78E56ABDEF" \
|
|
"E12D3C039B8A02D6BE593F0BBBDA56F1" \
|
|
"ECF677152EF804370C1A305CAF3B5BF1" \
|
|
"30879B56C61DE584A0F53A2447A51E" ) );
|
|
|
|
if( verbose != 0 )
|
|
printf( " MPI test #1 (mul_mpi): " );
|
|
|
|
if( mpi_cmp_mpi( &X, &U ) != 0 )
|
|
{
|
|
if( verbose != 0 )
|
|
printf( "failed\n" );
|
|
|
|
return( 1 );
|
|
}
|
|
|
|
if( verbose != 0 )
|
|
printf( "passed\n" );
|
|
|
|
MPI_CHK( mpi_div_mpi( &X, &Y, &A, &N ) );
|
|
|
|
MPI_CHK( mpi_read_string( &U, 16,
|
|
"256567336059E52CAE22925474705F39A94" ) );
|
|
|
|
MPI_CHK( mpi_read_string( &V, 16,
|
|
"6613F26162223DF488E9CD48CC132C7A" \
|
|
"0AC93C701B001B092E4E5B9F73BCD27B" \
|
|
"9EE50D0657C77F374E903CDFA4C642" ) );
|
|
|
|
if( verbose != 0 )
|
|
printf( " MPI test #2 (div_mpi): " );
|
|
|
|
if( mpi_cmp_mpi( &X, &U ) != 0 ||
|
|
mpi_cmp_mpi( &Y, &V ) != 0 )
|
|
{
|
|
if( verbose != 0 )
|
|
printf( "failed\n" );
|
|
|
|
return( 1 );
|
|
}
|
|
|
|
if( verbose != 0 )
|
|
printf( "passed\n" );
|
|
|
|
MPI_CHK( mpi_exp_mod( &X, &A, &E, &N, NULL ) );
|
|
|
|
MPI_CHK( mpi_read_string( &U, 16,
|
|
"36E139AEA55215609D2816998ED020BB" \
|
|
"BD96C37890F65171D948E9BC7CBAA4D9" \
|
|
"325D24D6A3C12710F10A09FA08AB87" ) );
|
|
|
|
if( verbose != 0 )
|
|
printf( " MPI test #3 (exp_mod): " );
|
|
|
|
if( mpi_cmp_mpi( &X, &U ) != 0 )
|
|
{
|
|
if( verbose != 0 )
|
|
printf( "failed\n" );
|
|
|
|
return( 1 );
|
|
}
|
|
|
|
if( verbose != 0 )
|
|
printf( "passed\n" );
|
|
|
|
MPI_CHK( mpi_inv_mod( &X, &A, &N ) );
|
|
|
|
MPI_CHK( mpi_read_string( &U, 16,
|
|
"003A0AAEDD7E784FC07D8F9EC6E3BFD5" \
|
|
"C3DBA76456363A10869622EAC2DD84EC" \
|
|
"C5B8A74DAC4D09E03B5E0BE779F2DF61" ) );
|
|
|
|
if( verbose != 0 )
|
|
printf( " MPI test #4 (inv_mod): " );
|
|
|
|
if( mpi_cmp_mpi( &X, &U ) != 0 )
|
|
{
|
|
if( verbose != 0 )
|
|
printf( "failed\n" );
|
|
|
|
return( 1 );
|
|
}
|
|
|
|
if( verbose != 0 )
|
|
printf( "passed\n" );
|
|
|
|
if( verbose != 0 )
|
|
printf( " MPI test #5 (simple gcd): " );
|
|
|
|
for ( i = 0; i < GCD_PAIR_COUNT; i++)
|
|
{
|
|
MPI_CHK( mpi_lset( &X, gcd_pairs[i][0] ) );
|
|
MPI_CHK( mpi_lset( &Y, gcd_pairs[i][1] ) );
|
|
|
|
MPI_CHK( mpi_gcd( &A, &X, &Y ) );
|
|
|
|
if( mpi_cmp_int( &A, gcd_pairs[i][2] ) != 0 )
|
|
{
|
|
if( verbose != 0 )
|
|
printf( "failed at %d\n", i );
|
|
|
|
return( 1 );
|
|
}
|
|
}
|
|
|
|
if( verbose != 0 )
|
|
printf( "passed\n" );
|
|
|
|
cleanup:
|
|
|
|
if( ret != 0 && verbose != 0 )
|
|
printf( "Unexpected error, return code = %08X\n", ret );
|
|
|
|
mpi_free( &V, &U, &Y, &X, &N, &E, &A, NULL );
|
|
|
|
if( verbose != 0 )
|
|
printf( "\n" );
|
|
|
|
return( ret );
|
|
}
|
|
|
|
#endif
|
|
|
|
#endif
|