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			2098 lines
		
	
	
		
			42 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			2098 lines
		
	
	
		
			42 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  *  Multi-precision integer library
 | |
|  *
 | |
|  *  Copyright (C) 2006-2010, Brainspark B.V.
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|  *
 | |
|  *  This file is part of PolarSSL (http://www.polarssl.org)
 | |
|  *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
 | |
|  *
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|  *  All rights reserved.
 | |
|  *
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|  *  This program 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
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|  *  (at your option) any later version.
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|  *
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|  *  This program is distributed in the hope that it will be useful,
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|  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 | |
|  *  GNU General Public License for more details.
 | |
|  *
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|  *  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.,
 | |
|  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 | |
|  */
 | |
| /*
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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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|  */
 | |
| 
 | |
| #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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| 
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| #include <stdlib.h>
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| 
 | |
| #define ciL    (sizeof(t_uint))         /* 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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|  * Convert between bits/chars and number of limbs
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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 MPI
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|  */
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| void mpi_init( mpi *X )
 | |
| {
 | |
|     if( X == NULL )
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|         return;
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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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| }
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| 
 | |
| /*
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|  * Unallocate one MPI
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|  */
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| void mpi_free( mpi *X )
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| {
 | |
|     if( X == NULL )
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|         return;
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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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| 
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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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| }
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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, size_t nblimbs )
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| {
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|     t_uint *p;
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| 
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|     if( nblimbs > POLARSSL_MPI_MAX_LIMBS )
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|         return( 1 );
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| 
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|     if( X->n < nblimbs )
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|     {
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|         if( ( p = (t_uint *) malloc( nblimbs * ciL ) ) == NULL )
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|             return( 1 );
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| 
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|         memset( p, 0, nblimbs * ciL );
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| 
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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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| 
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|         X->n = nblimbs;
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|         X->p = p;
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|     }
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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, const mpi *Y )
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| {
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|     int ret;
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|     size_t i;
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| 
 | |
|     if( X == Y )
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|         return( 0 );
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| 
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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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| 
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|     X->s = Y->s;
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| 
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|     MPI_CHK( mpi_grow( X, i ) );
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| 
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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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|  * 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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| 
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|     memcpy( &T,  X, sizeof( mpi ) );
 | |
|     memcpy(  X,  Y, sizeof( mpi ) );
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|     memcpy(  Y, &T, sizeof( mpi ) );
 | |
| }
 | |
| 
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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, t_sint z )
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| {
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|     int ret;
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| 
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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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| 
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|     X->p[0] = ( z < 0 ) ? -z : z;
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|     X->s    = ( z < 0 ) ? -1 : 1;
 | |
| 
 | |
| cleanup:
 | |
| 
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|     return( ret );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Get a specific bit
 | |
|  */
 | |
| int mpi_get_bit( mpi *X, size_t pos )
 | |
| {
 | |
|     if( X->n * biL <= pos )
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|         return( 0 );
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| 
 | |
|     return ( X->p[pos / biL] >> ( pos % biL ) ) & 0x01;
 | |
| }
 | |
| 
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| /*
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|  * Set a bit to a specific value of 0 or 1
 | |
|  */
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| int mpi_set_bit( mpi *X, size_t pos, unsigned char val )
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| {
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|     int ret = 0;
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|     size_t off = pos / biL;
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|     size_t idx = pos % biL;
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| 
 | |
|     if( val != 0 && val != 1 )
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|         return POLARSSL_ERR_MPI_BAD_INPUT_DATA;
 | |
|         
 | |
|     if( X->n * biL <= pos )
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|     {
 | |
|         if( val == 0 )
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|             return ( 0 );
 | |
| 
 | |
|         MPI_CHK( mpi_grow( X, off + 1 ) );
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|     }
 | |
| 
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|     X->p[off] = ( X->p[off] & ~( 0x01 << idx ) ) | ( val << idx );
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| 
 | |
| cleanup:
 | |
|     
 | |
|     return( ret );
 | |
| }
 | |
| 
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| /*
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|  * Return the number of least significant bits
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|  */
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| size_t mpi_lsb( const mpi *X )
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| {
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|     size_t i, j, count = 0;
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| 
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|     for( i = 0; i < X->n; i++ )
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|         for( j = 0; j < 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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| size_t mpi_msb( const mpi *X )
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| {
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|     size_t i, j;
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| 
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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; j > 0; j-- )
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|         if( ( ( X->p[i] >> ( j - 1 ) ) & 1 ) != 0 )
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|             break;
 | |
| 
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|     return( ( i * biL ) + j );
 | |
| }
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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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| size_t mpi_size( const 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_uint *d, int radix, char c )
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| {
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|     *d = 255;
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| 
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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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| 
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|     if( *d >= (t_uint) radix )
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|         return( POLARSSL_ERR_MPI_INVALID_CHARACTER );
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| 
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|     return( 0 );
 | |
| }
 | |
| 
 | |
| /*
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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, const char *s )
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| {
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|     int ret;
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|     size_t i, j, slen, n;
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|     t_uint d;
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|     mpi T;
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| 
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|     if( radix < 2 || radix > 16 )
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|         return( POLARSSL_ERR_MPI_BAD_INPUT_DATA );
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| 
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|     mpi_init( &T );
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| 
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|     slen = strlen( s );
 | |
| 
 | |
|     if( radix == 16 )
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|     {
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|         n = BITS_TO_LIMBS( slen << 2 );
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| 
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|         MPI_CHK( mpi_grow( X, n ) );
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|         MPI_CHK( mpi_lset( X, 0 ) );
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| 
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|         for( i = slen, j = 0; i > 0; i--, j++ )
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|         {
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|             if( i == 1 && s[i - 1] == '-' )
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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 - 1] ) );
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|             X->p[j / (2 * ciL)] |= d << ( (j % (2 * ciL)) << 2 );
 | |
|         }
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|     }
 | |
|     else
 | |
|     {
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|         MPI_CHK( mpi_lset( X, 0 ) );
 | |
| 
 | |
|         for( i = 0; i < slen; i++ )
 | |
|         {
 | |
|             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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|             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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| 
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|             if( X->s == 1 )
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|             {
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|                 MPI_CHK( mpi_add_int( X, &T, d ) );
 | |
|             }
 | |
|             else
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|             {
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|                 MPI_CHK( mpi_sub_int( X, &T, d ) );
 | |
|             }
 | |
|         }
 | |
|     }
 | |
| 
 | |
| cleanup:
 | |
| 
 | |
|     mpi_free( &T );
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| 
 | |
| /*
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|  * Helper to write the digits high-order first
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|  */
 | |
| static int mpi_write_hlp( mpi *X, int radix, char **p )
 | |
| {
 | |
|     int ret;
 | |
|     t_uint r;
 | |
| 
 | |
|     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 ) );
 | |
| 
 | |
|     if( r < 10 )
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|         *(*p)++ = (char)( r + 0x30 );
 | |
|     else
 | |
|         *(*p)++ = (char)( r + 0x37 );
 | |
| 
 | |
| cleanup:
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Export into an ASCII string
 | |
|  */
 | |
| int mpi_write_string( const mpi *X, int radix, char *s, size_t *slen )
 | |
| {
 | |
|     int ret = 0;
 | |
|     size_t n;
 | |
|     char *p;
 | |
|     mpi T;
 | |
| 
 | |
|     if( radix < 2 || radix > 16 )
 | |
|         return( POLARSSL_ERR_MPI_BAD_INPUT_DATA );
 | |
| 
 | |
|     n = mpi_msb( X );
 | |
|     if( radix >=  4 ) n >>= 1;
 | |
|     if( radix >= 16 ) n >>= 1;
 | |
|     n += 3;
 | |
| 
 | |
|     if( *slen < n )
 | |
|     {
 | |
|         *slen = n;
 | |
|         return( POLARSSL_ERR_MPI_BUFFER_TOO_SMALL );
 | |
|     }
 | |
| 
 | |
|     p = s;
 | |
|     mpi_init( &T );
 | |
| 
 | |
|     if( X->s == -1 )
 | |
|         *p++ = '-';
 | |
| 
 | |
|     if( radix == 16 )
 | |
|     {
 | |
|         int c;
 | |
|         size_t i, j, k;
 | |
| 
 | |
|         for( i = X->n, k = 0; i > 0; i-- )
 | |
|         {
 | |
|             for( j = ciL; j > 0; j-- )
 | |
|             {
 | |
|                 c = ( X->p[i - 1] >> ( ( j - 1 ) << 3) ) & 0xFF;
 | |
| 
 | |
|                 if( c == 0 && k == 0 && ( i + j + 3 ) != 0 )
 | |
|                     continue;
 | |
| 
 | |
|                 p += sprintf( p, "%02X", c );
 | |
|                 k = 1;
 | |
|             }
 | |
|         }
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         MPI_CHK( mpi_copy( &T, X ) );
 | |
| 
 | |
|         if( T.s == -1 )
 | |
|             T.s = 1;
 | |
| 
 | |
|         MPI_CHK( mpi_write_hlp( &T, radix, &p ) );
 | |
|     }
 | |
| 
 | |
|     *p++ = '\0';
 | |
|     *slen = p - s;
 | |
| 
 | |
| cleanup:
 | |
| 
 | |
|     mpi_free( &T );
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| 
 | |
| #if defined(POLARSSL_FS_IO)
 | |
| /*
 | |
|  * Read X from an opened file
 | |
|  */
 | |
| int mpi_read_file( mpi *X, int radix, FILE *fin )
 | |
| {
 | |
|     t_uint d;
 | |
|     size_t slen;
 | |
|     char *p;
 | |
|     char s[1024];
 | |
| 
 | |
|     memset( s, 0, sizeof( s ) );
 | |
|     if( fgets( s, sizeof( s ) - 1, fin ) == NULL )
 | |
|         return( POLARSSL_ERR_MPI_FILE_IO_ERROR );
 | |
| 
 | |
|     slen = strlen( s );
 | |
|     if( s[slen - 1] == '\n' ) { slen--; s[slen] = '\0'; }
 | |
|     if( s[slen - 1] == '\r' ) { slen--; s[slen] = '\0'; }
 | |
| 
 | |
|     p = s + slen;
 | |
|     while( --p >= s )
 | |
|         if( mpi_get_digit( &d, radix, *p ) != 0 )
 | |
|             break;
 | |
| 
 | |
|     return( mpi_read_string( X, radix, p + 1 ) );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Write X into an opened file (or stdout if fout == NULL)
 | |
|  */
 | |
| int mpi_write_file( const char *p, const mpi *X, int radix, FILE *fout )
 | |
| {
 | |
|     int ret;
 | |
|     size_t n, slen, plen;
 | |
|     char s[2048];
 | |
| 
 | |
|     n = sizeof( s );
 | |
|     memset( s, 0, n );
 | |
|     n -= 2;
 | |
| 
 | |
|     MPI_CHK( mpi_write_string( X, radix, s, (size_t *) &n ) );
 | |
| 
 | |
|     if( p == NULL ) p = "";
 | |
| 
 | |
|     plen = strlen( p );
 | |
|     slen = strlen( s );
 | |
|     s[slen++] = '\r';
 | |
|     s[slen++] = '\n';
 | |
| 
 | |
|     if( fout != NULL )
 | |
|     {
 | |
|         if( fwrite( p, 1, plen, fout ) != plen ||
 | |
|             fwrite( s, 1, slen, fout ) != slen )
 | |
|             return( POLARSSL_ERR_MPI_FILE_IO_ERROR );
 | |
|     }
 | |
|     else
 | |
|         printf( "%s%s", p, s );
 | |
| 
 | |
| cleanup:
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| #endif /* POLARSSL_FS_IO */
 | |
| 
 | |
| /*
 | |
|  * Import X from unsigned binary data, big endian
 | |
|  */
 | |
| int mpi_read_binary( mpi *X, const unsigned char *buf, size_t buflen )
 | |
| {
 | |
|     int ret;
 | |
|     size_t i, j, n;
 | |
| 
 | |
|     for( n = 0; n < buflen; n++ )
 | |
|         if( buf[n] != 0 )
 | |
|             break;
 | |
| 
 | |
|     MPI_CHK( mpi_grow( X, CHARS_TO_LIMBS( buflen - n ) ) );
 | |
|     MPI_CHK( mpi_lset( X, 0 ) );
 | |
| 
 | |
|     for( i = buflen, j = 0; i > n; i--, j++ )
 | |
|         X->p[j / ciL] |= ((t_uint) buf[i - 1]) << ((j % ciL) << 3);
 | |
| 
 | |
| cleanup:
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Export X into unsigned binary data, big endian
 | |
|  */
 | |
| int mpi_write_binary( const mpi *X, unsigned char *buf, size_t buflen )
 | |
| {
 | |
|     size_t i, j, n;
 | |
| 
 | |
|     n = mpi_size( X );
 | |
| 
 | |
|     if( buflen < n )
 | |
|         return( POLARSSL_ERR_MPI_BUFFER_TOO_SMALL );
 | |
| 
 | |
|     memset( buf, 0, buflen );
 | |
| 
 | |
|     for( i = buflen - 1, j = 0; n > 0; i--, j++, n-- )
 | |
|         buf[i] = (unsigned char)( X->p[j / ciL] >> ((j % ciL) << 3) );
 | |
| 
 | |
|     return( 0 );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Left-shift: X <<= count
 | |
|  */
 | |
| int mpi_shift_l( mpi *X, size_t count )
 | |
| {
 | |
|     int ret;
 | |
|     size_t i, v0, t1;
 | |
|     t_uint r0 = 0, r1;
 | |
| 
 | |
|     v0 = count / (biL    );
 | |
|     t1 = count & (biL - 1);
 | |
| 
 | |
|     i = mpi_msb( X ) + count;
 | |
| 
 | |
|     if( X->n * biL < i )
 | |
|         MPI_CHK( mpi_grow( X, BITS_TO_LIMBS( i ) ) );
 | |
| 
 | |
|     ret = 0;
 | |
| 
 | |
|     /*
 | |
|      * shift by count / limb_size
 | |
|      */
 | |
|     if( v0 > 0 )
 | |
|     {
 | |
|         for( i = X->n; i > v0; i-- )
 | |
|             X->p[i - 1] = X->p[i - v0 - 1];
 | |
| 
 | |
|         for( ; i > 0; i-- )
 | |
|             X->p[i - 1] = 0;
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * shift by count % limb_size
 | |
|      */
 | |
|     if( t1 > 0 )
 | |
|     {
 | |
|         for( i = v0; i < X->n; i++ )
 | |
|         {
 | |
|             r1 = X->p[i] >> (biL - t1);
 | |
|             X->p[i] <<= t1;
 | |
|             X->p[i] |= r0;
 | |
|             r0 = r1;
 | |
|         }
 | |
|     }
 | |
| 
 | |
| cleanup:
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Right-shift: X >>= count
 | |
|  */
 | |
| int mpi_shift_r( mpi *X, size_t count )
 | |
| {
 | |
|     size_t i, v0, v1;
 | |
|     t_uint r0 = 0, r1;
 | |
| 
 | |
|     v0 = count /  biL;
 | |
|     v1 = count & (biL - 1);
 | |
| 
 | |
|     /*
 | |
|      * shift by count / limb_size
 | |
|      */
 | |
|     if( v0 > 0 )
 | |
|     {
 | |
|         for( i = 0; i < X->n - v0; i++ )
 | |
|             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; i > 0; i-- )
 | |
|         {
 | |
|             r1 = X->p[i - 1] << (biL - v1);
 | |
|             X->p[i - 1] >>= v1;
 | |
|             X->p[i - 1] |= r0;
 | |
|             r0 = r1;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     return( 0 );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Compare unsigned values
 | |
|  */
 | |
| int mpi_cmp_abs( const mpi *X, const mpi *Y )
 | |
| {
 | |
|     size_t i, j;
 | |
| 
 | |
|     for( i = X->n; i > 0; i-- )
 | |
|         if( X->p[i - 1] != 0 )
 | |
|             break;
 | |
| 
 | |
|     for( j = Y->n; j > 0; j-- )
 | |
|         if( Y->p[j - 1] != 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 - 1] > Y->p[i - 1] ) return(  1 );
 | |
|         if( X->p[i - 1] < Y->p[i - 1] ) return( -1 );
 | |
|     }
 | |
| 
 | |
|     return( 0 );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Compare signed values
 | |
|  */
 | |
| int mpi_cmp_mpi( const mpi *X, const mpi *Y )
 | |
| {
 | |
|     size_t i, j;
 | |
| 
 | |
|     for( i = X->n; i > 0; i-- )
 | |
|         if( X->p[i - 1] != 0 )
 | |
|             break;
 | |
| 
 | |
|     for( j = Y->n; j > 0; j-- )
 | |
|         if( Y->p[j - 1] != 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 - 1] > Y->p[i - 1] ) return(  X->s );
 | |
|         if( X->p[i - 1] < Y->p[i - 1] ) return( -X->s );
 | |
|     }
 | |
| 
 | |
|     return( 0 );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Compare signed values
 | |
|  */
 | |
| int mpi_cmp_int( const mpi *X, t_sint z )
 | |
| {
 | |
|     mpi Y;
 | |
|     t_uint 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, const mpi *A, const mpi *B )
 | |
| {
 | |
|     int ret;
 | |
|     size_t i, j;
 | |
|     t_uint *o, *p, c;
 | |
| 
 | |
|     if( X == B )
 | |
|     {
 | |
|         const mpi *T = A; A = X; B = T;
 | |
|     }
 | |
| 
 | |
|     if( X != A )
 | |
|         MPI_CHK( mpi_copy( X, A ) );
 | |
|    
 | |
|     /*
 | |
|      * X should always be positive as a result of unsigned additions.
 | |
|      */
 | |
|     X->s = 1;
 | |
| 
 | |
|     for( j = B->n; j > 0; j-- )
 | |
|         if( B->p[j - 1] != 0 )
 | |
|             break;
 | |
| 
 | |
|     MPI_CHK( mpi_grow( X, j ) );
 | |
| 
 | |
|     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( size_t n, t_uint *s, t_uint *d )
 | |
| {
 | |
|     size_t i;
 | |
|     t_uint 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, const mpi *A, const mpi *B )
 | |
| {
 | |
|     mpi TB;
 | |
|     int ret;
 | |
|     size_t n;
 | |
| 
 | |
|     if( mpi_cmp_abs( A, B ) < 0 )
 | |
|         return( POLARSSL_ERR_MPI_NEGATIVE_VALUE );
 | |
| 
 | |
|     mpi_init( &TB );
 | |
| 
 | |
|     if( X == B )
 | |
|     {
 | |
|         MPI_CHK( mpi_copy( &TB, B ) );
 | |
|         B = &TB;
 | |
|     }
 | |
| 
 | |
|     if( X != A )
 | |
|         MPI_CHK( mpi_copy( X, A ) );
 | |
| 
 | |
|     /*
 | |
|      * X should always be positive as a result of unsigned substractions.
 | |
|      */
 | |
|     X->s = 1;
 | |
| 
 | |
|     ret = 0;
 | |
| 
 | |
|     for( n = B->n; n > 0; n-- )
 | |
|         if( B->p[n - 1] != 0 )
 | |
|             break;
 | |
| 
 | |
|     mpi_sub_hlp( n, B->p, X->p );
 | |
| 
 | |
| cleanup:
 | |
| 
 | |
|     mpi_free( &TB );
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Signed addition: X = A + B
 | |
|  */
 | |
| int mpi_add_mpi( mpi *X, const mpi *A, const 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, const mpi *A, const 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, const mpi *A, t_sint b )
 | |
| {
 | |
|     mpi _B;
 | |
|     t_uint 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, const mpi *A, t_sint b )
 | |
| {
 | |
|     mpi _B;
 | |
|     t_uint 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( size_t i, t_uint *s, t_uint *d, t_uint b )
 | |
| {
 | |
|     t_uint 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, const mpi *A, const mpi *B )
 | |
| {
 | |
|     int ret;
 | |
|     size_t i, j;
 | |
|     mpi TA, TB;
 | |
| 
 | |
|     mpi_init( &TA ); mpi_init( &TB );
 | |
| 
 | |
|     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; i > 0; i-- )
 | |
|         if( A->p[i - 1] != 0 )
 | |
|             break;
 | |
| 
 | |
|     for( j = B->n; j > 0; j-- )
 | |
|         if( B->p[j - 1] != 0 )
 | |
|             break;
 | |
| 
 | |
|     MPI_CHK( mpi_grow( X, i + j ) );
 | |
|     MPI_CHK( mpi_lset( X, 0 ) );
 | |
| 
 | |
|     for( i++; j > 0; j-- )
 | |
|         mpi_mul_hlp( i - 1, A->p, X->p + j - 1, B->p[j - 1] );
 | |
| 
 | |
|     X->s = A->s * B->s;
 | |
| 
 | |
| cleanup:
 | |
| 
 | |
|     mpi_free( &TB ); mpi_free( &TA );
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Baseline multiplication: X = A * b
 | |
|  */
 | |
| int mpi_mul_int( mpi *X, const mpi *A, t_sint b )
 | |
| {
 | |
|     mpi _B;
 | |
|     t_uint 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, const mpi *A, const mpi *B )
 | |
| {
 | |
|     int ret;
 | |
|     size_t 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 ); mpi_init( &Y ); mpi_init( &Z );
 | |
|     mpi_init( &T1 ); mpi_init( &T2 );
 | |
| 
 | |
|     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 < 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_udbl r;
 | |
| 
 | |
|             r  = (t_udbl) X.p[i] << biL;
 | |
|             r |= (t_udbl) X.p[i - 1];
 | |
|             r /= Y.p[t];
 | |
|             if( r > ((t_udbl) 1 << biL) - 1)
 | |
|                 r = ((t_udbl) 1 << biL) - 1;
 | |
| 
 | |
|             Z.p[i - t - 1] = (t_uint) r;
 | |
| #else
 | |
|             /*
 | |
|              * __udiv_qrnnd_c, from gmp/longlong.h
 | |
|              */
 | |
|             t_uint q0, q1, r0, r1;
 | |
|             t_uint 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 ); mpi_free( &Y ); mpi_free( &Z );
 | |
|     mpi_free( &T1 ); mpi_free( &T2 );
 | |
| 
 | |
|     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, const mpi *A, t_sint b )
 | |
| {
 | |
|     mpi _B;
 | |
|     t_uint 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, const mpi *A, const mpi *B )
 | |
| {
 | |
|     int ret;
 | |
| 
 | |
|     if( mpi_cmp_int( B, 0 ) < 0 )
 | |
|         return POLARSSL_ERR_MPI_NEGATIVE_VALUE;
 | |
| 
 | |
|     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_uint *r, const mpi *A, t_sint b )
 | |
| {
 | |
|     size_t i;
 | |
|     t_uint x, y, z;
 | |
| 
 | |
|     if( b == 0 )
 | |
|         return( POLARSSL_ERR_MPI_DIVISION_BY_ZERO );
 | |
| 
 | |
|     if( b < 0 )
 | |
|         return POLARSSL_ERR_MPI_NEGATIVE_VALUE;
 | |
| 
 | |
|     /*
 | |
|      * 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, y = 0; i > 0; i-- )
 | |
|     {
 | |
|         x  = A->p[i - 1];
 | |
|         y  = ( y << biH ) | ( x >> biH );
 | |
|         z  = y / b;
 | |
|         y -= z * b;
 | |
| 
 | |
|         x <<= biH;
 | |
|         y  = ( y << biH ) | ( x >> biH );
 | |
|         z  = y / b;
 | |
|         y -= z * b;
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * If A is negative, then the current y represents a negative value.
 | |
|      * Flipping it to the positive side.
 | |
|      */
 | |
|     if( A->s < 0 && y != 0 )
 | |
|         y = b - y;
 | |
| 
 | |
|     *r = y;
 | |
| 
 | |
|     return( 0 );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Fast Montgomery initialization (thanks to Tom St Denis)
 | |
|  */
 | |
| static void mpi_montg_init( t_uint *mm, const mpi *N )
 | |
| {
 | |
|     t_uint 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, const mpi *B, const mpi *N, t_uint mm, const mpi *T )
 | |
| {
 | |
|     size_t i, n, m;
 | |
|     t_uint 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, const mpi *N, t_uint mm, const mpi *T )
 | |
| {
 | |
|     t_uint 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, const mpi *A, const mpi *E, const mpi *N, mpi *_RR )
 | |
| {
 | |
|     int ret;
 | |
|     size_t wbits, wsize, one = 1;
 | |
|     size_t i, j, nblimbs;
 | |
|     size_t bufsize, nbits;
 | |
|     t_uint 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 ); mpi_init( &T );
 | |
|     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 =  one << (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 < (one << 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_uint ) << 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 & (one << 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 = (one << (wsize - 1)); i < (one << wsize); i++ )
 | |
|         mpi_free( &W[i] );
 | |
| 
 | |
|     mpi_free( &W[1] ); mpi_free( &T );
 | |
| 
 | |
|     if( _RR == NULL )
 | |
|         mpi_free( &RR );
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Greatest common divisor: G = gcd(A, B)  (HAC 14.54)
 | |
|  */
 | |
| int mpi_gcd( mpi *G, const mpi *A, const mpi *B )
 | |
| {
 | |
|     int ret;
 | |
|     size_t lz, lzt;
 | |
|     mpi TG, TA, TB;
 | |
| 
 | |
|     mpi_init( &TG ); mpi_init( &TA ); mpi_init( &TB );
 | |
| 
 | |
|     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( &TG ); mpi_free( &TA ); mpi_free( &TB );
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| 
 | |
| int mpi_fill_random( mpi *X, size_t size, int (*f_rng)(void *), void *p_rng )
 | |
| {
 | |
|     int ret;
 | |
|     size_t k;
 | |
|     unsigned char *p;
 | |
| 
 | |
|     MPI_CHK( mpi_grow( X, size ) );
 | |
|     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 );
 | |
| 
 | |
| cleanup:
 | |
|     return( ret );
 | |
| }
 | |
| 
 | |
| #if defined(POLARSSL_GENPRIME)
 | |
| 
 | |
| /*
 | |
|  * Modular inverse: X = A^-1 mod N  (HAC 14.61 / 14.64)
 | |
|  */
 | |
| int mpi_inv_mod( mpi *X, const mpi *A, const 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 ); mpi_init( &TU ); mpi_init( &U1 ); mpi_init( &U2 );
 | |
|     mpi_init( &G ); mpi_init( &TB ); mpi_init( &TV );
 | |
|     mpi_init( &V1 ); mpi_init( &V2 );
 | |
| 
 | |
|     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( &TA ); mpi_free( &TU ); mpi_free( &U1 ); mpi_free( &U2 );
 | |
|     mpi_free( &G ); mpi_free( &TB ); mpi_free( &TV );
 | |
|     mpi_free( &V1 ); mpi_free( &V2 );
 | |
| 
 | |
|     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, xs;
 | |
|     size_t i, j, n, s;
 | |
|     mpi W, R, T, A, RR;
 | |
| 
 | |
|     if( mpi_cmp_int( X, 0 ) == 0 ||
 | |
|         mpi_cmp_int( X, 1 ) == 0 )
 | |
|         return( POLARSSL_ERR_MPI_NOT_ACCEPTABLE );
 | |
| 
 | |
|     if( mpi_cmp_int( X, 2 ) == 0 )
 | |
|         return( 0 );
 | |
| 
 | |
|     mpi_init( &W ); mpi_init( &R ); mpi_init( &T ); mpi_init( &A );
 | |
|     mpi_init( &RR );
 | |
| 
 | |
|     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_uint 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 )
 | |
|      */
 | |
|     MPI_CHK( mpi_sub_int( &W, X, 1 ) );
 | |
|     s = mpi_lsb( &W );
 | |
|     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_fill_random( &A, X->n, f_rng, p_rng );
 | |
| 
 | |
|         if( mpi_cmp_mpi( &A, &W ) >= 0 )
 | |
|         {
 | |
|             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( &W ); mpi_free( &R ); mpi_free( &T ); mpi_free( &A );
 | |
|     mpi_free( &RR );
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Prime number generation
 | |
|  */
 | |
| int mpi_gen_prime( mpi *X, size_t nbits, int dh_flag,
 | |
|                    int (*f_rng)(void *), void *p_rng )
 | |
| {
 | |
|     int ret;
 | |
|     size_t k, n;
 | |
|     mpi Y;
 | |
| 
 | |
|     if( nbits < 3 || nbits > 4096 )
 | |
|         return( POLARSSL_ERR_MPI_BAD_INPUT_DATA );
 | |
| 
 | |
|     mpi_init( &Y );
 | |
| 
 | |
|     n = BITS_TO_LIMBS( nbits );
 | |
| 
 | |
|     mpi_fill_random( X, n, 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 );
 | |
| 
 | |
|     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 ); mpi_init( &E ); mpi_init( &N ); mpi_init( &X );
 | |
|     mpi_init( &Y ); mpi_init( &U ); mpi_init( &V );
 | |
| 
 | |
|     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" );
 | |
| 
 | |
| #if defined(POLARSSL_GENPRIME)
 | |
|     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" );
 | |
| #endif
 | |
| 
 | |
|     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( &A ); mpi_free( &E ); mpi_free( &N ); mpi_free( &X );
 | |
|     mpi_free( &Y ); mpi_free( &U ); mpi_free( &V );
 | |
| 
 | |
|     if( verbose != 0 )
 | |
|         printf( "\n" );
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| 
 | |
| #endif
 | |
| 
 | |
| #endif
 |