|  | /* | 
|  | *  Multi-precision integer library | 
|  | * | 
|  | *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved | 
|  | *  SPDX-License-Identifier: Apache-2.0 | 
|  | * | 
|  | *  Licensed under the Apache License, Version 2.0 (the "License"); you may | 
|  | *  not use this file except in compliance with the License. | 
|  | *  You may obtain a copy of the License at | 
|  | * | 
|  | *  http://www.apache.org/licenses/LICENSE-2.0 | 
|  | * | 
|  | *  Unless required by applicable law or agreed to in writing, software | 
|  | *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT | 
|  | *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | 
|  | *  See the License for the specific language governing permissions and | 
|  | *  limitations under the License. | 
|  | * | 
|  | *  This file is part of mbed TLS (https://tls.mbed.org) | 
|  | */ | 
|  |  | 
|  | /* | 
|  | *  The following sources were referenced in the design of this Multi-precision | 
|  | *  Integer library: | 
|  | * | 
|  | *  [1] Handbook of Applied Cryptography - 1997 | 
|  | *      Menezes, van Oorschot and Vanstone | 
|  | * | 
|  | *  [2] Multi-Precision Math | 
|  | *      Tom St Denis | 
|  | *      https://github.com/libtom/libtommath/blob/develop/tommath.pdf | 
|  | * | 
|  | *  [3] GNU Multi-Precision Arithmetic Library | 
|  | *      https://gmplib.org/manual/index.html | 
|  | * | 
|  | */ | 
|  |  | 
|  | #if !defined(MBEDTLS_CONFIG_FILE) | 
|  | #include "mbedtls/config.h" | 
|  | #else | 
|  | #include MBEDTLS_CONFIG_FILE | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_BIGNUM_C) | 
|  |  | 
|  | #include "mbedtls/bignum.h" | 
|  | #include "mbedtls/bn_mul.h" | 
|  | #include "mbedtls/platform_util.h" | 
|  |  | 
|  | #include <string.h> | 
|  |  | 
|  | #if defined(MBEDTLS_PLATFORM_C) | 
|  | #include "mbedtls/platform.h" | 
|  | #else | 
|  | #include <stdio.h> | 
|  | #include <stdlib.h> | 
|  | #define mbedtls_printf     printf | 
|  | #define mbedtls_calloc    calloc | 
|  | #define mbedtls_free       free | 
|  | #endif | 
|  |  | 
|  | #define ciL    (sizeof(mbedtls_mpi_uint))         /* chars in limb  */ | 
|  | #define biL    (ciL << 3)               /* bits  in limb  */ | 
|  | #define biH    (ciL << 2)               /* half limb size */ | 
|  |  | 
|  | #define MPI_SIZE_T_MAX  ( (size_t) -1 ) /* SIZE_T_MAX is not standard */ | 
|  |  | 
|  | /* | 
|  | * Convert between bits/chars and number of limbs | 
|  | * Divide first in order to avoid potential overflows | 
|  | */ | 
|  | #define BITS_TO_LIMBS(i)  ( (i) / biL + ( (i) % biL != 0 ) ) | 
|  | #define CHARS_TO_LIMBS(i) ( (i) / ciL + ( (i) % ciL != 0 ) ) | 
|  |  | 
|  | /* Implementation that should never be optimized out by the compiler */ | 
|  | static void mbedtls_mpi_zeroize( mbedtls_mpi_uint *v, size_t n ) | 
|  | { | 
|  | mbedtls_platform_zeroize( v, ciL * n ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Initialize one MPI | 
|  | */ | 
|  | void mbedtls_mpi_init( mbedtls_mpi *X ) | 
|  | { | 
|  | if( X == NULL ) | 
|  | return; | 
|  |  | 
|  | X->s = 1; | 
|  | X->n = 0; | 
|  | X->p = NULL; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Unallocate one MPI | 
|  | */ | 
|  | void mbedtls_mpi_free( mbedtls_mpi *X ) | 
|  | { | 
|  | if( X == NULL ) | 
|  | return; | 
|  |  | 
|  | if( X->p != NULL ) | 
|  | { | 
|  | mbedtls_mpi_zeroize( X->p, X->n ); | 
|  | mbedtls_free( X->p ); | 
|  | } | 
|  |  | 
|  | X->s = 1; | 
|  | X->n = 0; | 
|  | X->p = NULL; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Enlarge to the specified number of limbs | 
|  | */ | 
|  | int mbedtls_mpi_grow( mbedtls_mpi *X, size_t nblimbs ) | 
|  | { | 
|  | mbedtls_mpi_uint *p; | 
|  |  | 
|  | if( nblimbs > MBEDTLS_MPI_MAX_LIMBS ) | 
|  | return( MBEDTLS_ERR_MPI_ALLOC_FAILED ); | 
|  |  | 
|  | if( X->n < nblimbs ) | 
|  | { | 
|  | if( ( p = (mbedtls_mpi_uint*)mbedtls_calloc( nblimbs, ciL ) ) == NULL ) | 
|  | return( MBEDTLS_ERR_MPI_ALLOC_FAILED ); | 
|  |  | 
|  | if( X->p != NULL ) | 
|  | { | 
|  | memcpy( p, X->p, X->n * ciL ); | 
|  | mbedtls_mpi_zeroize( X->p, X->n ); | 
|  | mbedtls_free( X->p ); | 
|  | } | 
|  |  | 
|  | X->n = nblimbs; | 
|  | X->p = p; | 
|  | } | 
|  |  | 
|  | return( 0 ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Resize down as much as possible, | 
|  | * while keeping at least the specified number of limbs | 
|  | */ | 
|  | int mbedtls_mpi_shrink( mbedtls_mpi *X, size_t nblimbs ) | 
|  | { | 
|  | mbedtls_mpi_uint *p; | 
|  | size_t i; | 
|  |  | 
|  | /* Actually resize up in this case */ | 
|  | if( X->n <= nblimbs ) | 
|  | return( mbedtls_mpi_grow( X, nblimbs ) ); | 
|  |  | 
|  | for( i = X->n - 1; i > 0; i-- ) | 
|  | if( X->p[i] != 0 ) | 
|  | break; | 
|  | i++; | 
|  |  | 
|  | if( i < nblimbs ) | 
|  | i = nblimbs; | 
|  |  | 
|  | if( ( p = (mbedtls_mpi_uint*)mbedtls_calloc( i, ciL ) ) == NULL ) | 
|  | return( MBEDTLS_ERR_MPI_ALLOC_FAILED ); | 
|  |  | 
|  | if( X->p != NULL ) | 
|  | { | 
|  | memcpy( p, X->p, i * ciL ); | 
|  | mbedtls_mpi_zeroize( X->p, X->n ); | 
|  | mbedtls_free( X->p ); | 
|  | } | 
|  |  | 
|  | X->n = i; | 
|  | X->p = p; | 
|  |  | 
|  | return( 0 ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Copy the contents of Y into X | 
|  | */ | 
|  | int mbedtls_mpi_copy( mbedtls_mpi *X, const mbedtls_mpi *Y ) | 
|  | { | 
|  | int ret = 0; | 
|  | size_t i; | 
|  |  | 
|  | if( X == Y ) | 
|  | return( 0 ); | 
|  |  | 
|  | if( Y->p == NULL ) | 
|  | { | 
|  | mbedtls_mpi_free( X ); | 
|  | return( 0 ); | 
|  | } | 
|  |  | 
|  | for( i = Y->n - 1; i > 0; i-- ) | 
|  | if( Y->p[i] != 0 ) | 
|  | break; | 
|  | i++; | 
|  |  | 
|  | X->s = Y->s; | 
|  |  | 
|  | if( X->n < i ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( X, i ) ); | 
|  | } | 
|  | else | 
|  | { | 
|  | memset( X->p + i, 0, ( X->n - i ) * ciL ); | 
|  | } | 
|  |  | 
|  | memcpy( X->p, Y->p, i * ciL ); | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Swap the contents of X and Y | 
|  | */ | 
|  | void mbedtls_mpi_swap( mbedtls_mpi *X, mbedtls_mpi *Y ) | 
|  | { | 
|  | mbedtls_mpi T; | 
|  |  | 
|  | memcpy( &T,  X, sizeof( mbedtls_mpi ) ); | 
|  | memcpy(  X,  Y, sizeof( mbedtls_mpi ) ); | 
|  | memcpy(  Y, &T, sizeof( mbedtls_mpi ) ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Conditionally assign X = Y, without leaking information | 
|  | * about whether the assignment was made or not. | 
|  | * (Leaking information about the respective sizes of X and Y is ok however.) | 
|  | */ | 
|  | int mbedtls_mpi_safe_cond_assign( mbedtls_mpi *X, const mbedtls_mpi *Y, unsigned char assign ) | 
|  | { | 
|  | int ret = 0; | 
|  | size_t i; | 
|  |  | 
|  | /* make sure assign is 0 or 1 in a time-constant manner */ | 
|  | assign = (assign | (unsigned char)-assign) >> 7; | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( X, Y->n ) ); | 
|  |  | 
|  | X->s = X->s * ( 1 - assign ) + Y->s * assign; | 
|  |  | 
|  | for( i = 0; i < Y->n; i++ ) | 
|  | X->p[i] = X->p[i] * ( 1 - assign ) + Y->p[i] * assign; | 
|  |  | 
|  | for( ; i < X->n; i++ ) | 
|  | X->p[i] *= ( 1 - assign ); | 
|  |  | 
|  | cleanup: | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Conditionally swap X and Y, without leaking information | 
|  | * about whether the swap was made or not. | 
|  | * Here it is not ok to simply swap the pointers, which whould lead to | 
|  | * different memory access patterns when X and Y are used afterwards. | 
|  | */ | 
|  | int mbedtls_mpi_safe_cond_swap( mbedtls_mpi *X, mbedtls_mpi *Y, unsigned char swap ) | 
|  | { | 
|  | int ret, s; | 
|  | size_t i; | 
|  | mbedtls_mpi_uint tmp; | 
|  |  | 
|  | if( X == Y ) | 
|  | return( 0 ); | 
|  |  | 
|  | /* make sure swap is 0 or 1 in a time-constant manner */ | 
|  | swap = (swap | (unsigned char)-swap) >> 7; | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( X, Y->n ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( Y, X->n ) ); | 
|  |  | 
|  | s = X->s; | 
|  | X->s = X->s * ( 1 - swap ) + Y->s * swap; | 
|  | Y->s = Y->s * ( 1 - swap ) +    s * swap; | 
|  |  | 
|  |  | 
|  | for( i = 0; i < X->n; i++ ) | 
|  | { | 
|  | tmp = X->p[i]; | 
|  | X->p[i] = X->p[i] * ( 1 - swap ) + Y->p[i] * swap; | 
|  | Y->p[i] = Y->p[i] * ( 1 - swap ) +     tmp * swap; | 
|  | } | 
|  |  | 
|  | cleanup: | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Set value from integer | 
|  | */ | 
|  | int mbedtls_mpi_lset( mbedtls_mpi *X, mbedtls_mpi_sint z ) | 
|  | { | 
|  | int ret; | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( X, 1 ) ); | 
|  | memset( X->p, 0, X->n * ciL ); | 
|  |  | 
|  | X->p[0] = ( z < 0 ) ? -z : z; | 
|  | X->s    = ( z < 0 ) ? -1 : 1; | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Get a specific bit | 
|  | */ | 
|  | int mbedtls_mpi_get_bit( const mbedtls_mpi *X, size_t pos ) | 
|  | { | 
|  | if( X->n * biL <= pos ) | 
|  | return( 0 ); | 
|  |  | 
|  | return( ( X->p[pos / biL] >> ( pos % biL ) ) & 0x01 ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Set a bit to a specific value of 0 or 1 | 
|  | */ | 
|  | int mbedtls_mpi_set_bit( mbedtls_mpi *X, size_t pos, unsigned char val ) | 
|  | { | 
|  | int ret = 0; | 
|  | size_t off = pos / biL; | 
|  | size_t idx = pos % biL; | 
|  |  | 
|  | if( val != 0 && val != 1 ) | 
|  | return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA ); | 
|  |  | 
|  | if( X->n * biL <= pos ) | 
|  | { | 
|  | if( val == 0 ) | 
|  | return( 0 ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( X, off + 1 ) ); | 
|  | } | 
|  |  | 
|  | X->p[off] &= ~( (mbedtls_mpi_uint) 0x01 << idx ); | 
|  | X->p[off] |= (mbedtls_mpi_uint) val << idx; | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Return the number of less significant zero-bits | 
|  | */ | 
|  | size_t mbedtls_mpi_lsb( const mbedtls_mpi *X ) | 
|  | { | 
|  | size_t i, j, count = 0; | 
|  |  | 
|  | for( i = 0; i < X->n; i++ ) | 
|  | for( j = 0; j < biL; j++, count++ ) | 
|  | if( ( ( X->p[i] >> j ) & 1 ) != 0 ) | 
|  | return( count ); | 
|  |  | 
|  | return( 0 ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Count leading zero bits in a given integer | 
|  | */ | 
|  | static size_t mbedtls_clz( const mbedtls_mpi_uint x ) | 
|  | { | 
|  | size_t j; | 
|  | mbedtls_mpi_uint mask = (mbedtls_mpi_uint) 1 << (biL - 1); | 
|  |  | 
|  | for( j = 0; j < biL; j++ ) | 
|  | { | 
|  | if( x & mask ) break; | 
|  |  | 
|  | mask >>= 1; | 
|  | } | 
|  |  | 
|  | return j; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Return the number of bits | 
|  | */ | 
|  | size_t mbedtls_mpi_bitlen( const mbedtls_mpi *X ) | 
|  | { | 
|  | size_t i, j; | 
|  |  | 
|  | if( X->n == 0 ) | 
|  | return( 0 ); | 
|  |  | 
|  | for( i = X->n - 1; i > 0; i-- ) | 
|  | if( X->p[i] != 0 ) | 
|  | break; | 
|  |  | 
|  | j = biL - mbedtls_clz( X->p[i] ); | 
|  |  | 
|  | return( ( i * biL ) + j ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Return the total size in bytes | 
|  | */ | 
|  | size_t mbedtls_mpi_size( const mbedtls_mpi *X ) | 
|  | { | 
|  | return( ( mbedtls_mpi_bitlen( X ) + 7 ) >> 3 ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Convert an ASCII character to digit value | 
|  | */ | 
|  | static int mpi_get_digit( mbedtls_mpi_uint *d, int radix, char c ) | 
|  | { | 
|  | *d = 255; | 
|  |  | 
|  | if( c >= 0x30 && c <= 0x39 ) *d = c - 0x30; | 
|  | if( c >= 0x41 && c <= 0x46 ) *d = c - 0x37; | 
|  | if( c >= 0x61 && c <= 0x66 ) *d = c - 0x57; | 
|  |  | 
|  | if( *d >= (mbedtls_mpi_uint) radix ) | 
|  | return( MBEDTLS_ERR_MPI_INVALID_CHARACTER ); | 
|  |  | 
|  | return( 0 ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Import from an ASCII string | 
|  | */ | 
|  | int mbedtls_mpi_read_string( mbedtls_mpi *X, int radix, const char *s ) | 
|  | { | 
|  | int ret; | 
|  | size_t i, j, slen, n; | 
|  | mbedtls_mpi_uint d; | 
|  | mbedtls_mpi T; | 
|  |  | 
|  | if( radix < 2 || radix > 16 ) | 
|  | return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA ); | 
|  |  | 
|  | mbedtls_mpi_init( &T ); | 
|  |  | 
|  | slen = strlen( s ); | 
|  |  | 
|  | if( radix == 16 ) | 
|  | { | 
|  | if( slen > MPI_SIZE_T_MAX >> 2 ) | 
|  | return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA ); | 
|  |  | 
|  | n = BITS_TO_LIMBS( slen << 2 ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( X, n ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( X, 0 ) ); | 
|  |  | 
|  | for( i = slen, j = 0; i > 0; i--, j++ ) | 
|  | { | 
|  | if( i == 1 && s[i - 1] == '-' ) | 
|  | { | 
|  | X->s = -1; | 
|  | break; | 
|  | } | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mpi_get_digit( &d, radix, s[i - 1] ) ); | 
|  | X->p[j / ( 2 * ciL )] |= d << ( ( j % ( 2 * ciL ) ) << 2 ); | 
|  | } | 
|  | } | 
|  | else | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( X, 0 ) ); | 
|  |  | 
|  | for( i = 0; i < slen; i++ ) | 
|  | { | 
|  | if( i == 0 && s[i] == '-' ) | 
|  | { | 
|  | X->s = -1; | 
|  | continue; | 
|  | } | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mpi_get_digit( &d, radix, s[i] ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_int( &T, X, radix ) ); | 
|  |  | 
|  | if( X->s == 1 ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_int( X, &T, d ) ); | 
|  | } | 
|  | else | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( X, &T, d ) ); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | mbedtls_mpi_free( &T ); | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Helper to write the digits high-order first | 
|  | */ | 
|  | static int mpi_write_hlp( mbedtls_mpi *X, int radix, char **p ) | 
|  | { | 
|  | int ret; | 
|  | mbedtls_mpi_uint r; | 
|  |  | 
|  | if( radix < 2 || radix > 16 ) | 
|  | return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_mod_int( &r, X, radix ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_div_int( X, NULL, X, radix ) ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( X, 0 ) != 0 ) | 
|  | MBEDTLS_MPI_CHK( mpi_write_hlp( X, radix, p ) ); | 
|  |  | 
|  | if( r < 10 ) | 
|  | *(*p)++ = (char)( r + 0x30 ); | 
|  | else | 
|  | *(*p)++ = (char)( r + 0x37 ); | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Export into an ASCII string | 
|  | */ | 
|  | int mbedtls_mpi_write_string( const mbedtls_mpi *X, int radix, | 
|  | char *buf, size_t buflen, size_t *olen ) | 
|  | { | 
|  | int ret = 0; | 
|  | size_t n; | 
|  | char *p; | 
|  | mbedtls_mpi T; | 
|  |  | 
|  | if( radix < 2 || radix > 16 ) | 
|  | return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA ); | 
|  |  | 
|  | n = mbedtls_mpi_bitlen( X ); | 
|  | if( radix >=  4 ) n >>= 1; | 
|  | if( radix >= 16 ) n >>= 1; | 
|  | /* | 
|  | * Round up the buffer length to an even value to ensure that there is | 
|  | * enough room for hexadecimal values that can be represented in an odd | 
|  | * number of digits. | 
|  | */ | 
|  | n += 3 + ( ( n + 1 ) & 1 ); | 
|  |  | 
|  | if( buflen < n ) | 
|  | { | 
|  | *olen = n; | 
|  | return( MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL ); | 
|  | } | 
|  |  | 
|  | p = buf; | 
|  | mbedtls_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 ) != 2 ) | 
|  | continue; | 
|  |  | 
|  | *(p++) = "0123456789ABCDEF" [c / 16]; | 
|  | *(p++) = "0123456789ABCDEF" [c % 16]; | 
|  | k = 1; | 
|  | } | 
|  | } | 
|  | } | 
|  | else | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &T, X ) ); | 
|  |  | 
|  | if( T.s == -1 ) | 
|  | T.s = 1; | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mpi_write_hlp( &T, radix, &p ) ); | 
|  | } | 
|  |  | 
|  | *p++ = '\0'; | 
|  | *olen = p - buf; | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | mbedtls_mpi_free( &T ); | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | #if defined(MBEDTLS_FS_IO) | 
|  | /* | 
|  | * Read X from an opened file | 
|  | */ | 
|  | int mbedtls_mpi_read_file( mbedtls_mpi *X, int radix, FILE *fin ) | 
|  | { | 
|  | mbedtls_mpi_uint d; | 
|  | size_t slen; | 
|  | char *p; | 
|  | /* | 
|  | * Buffer should have space for (short) label and decimal formatted MPI, | 
|  | * newline characters and '\0' | 
|  | */ | 
|  | char s[ MBEDTLS_MPI_RW_BUFFER_SIZE ]; | 
|  |  | 
|  | memset( s, 0, sizeof( s ) ); | 
|  | if( fgets( s, sizeof( s ) - 1, fin ) == NULL ) | 
|  | return( MBEDTLS_ERR_MPI_FILE_IO_ERROR ); | 
|  |  | 
|  | slen = strlen( s ); | 
|  | if( slen == sizeof( s ) - 2 ) | 
|  | return( MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL ); | 
|  |  | 
|  | if( slen > 0 && s[slen - 1] == '\n' ) { slen--; s[slen] = '\0'; } | 
|  | if( slen > 0 && s[slen - 1] == '\r' ) { slen--; s[slen] = '\0'; } | 
|  |  | 
|  | p = s + slen; | 
|  | while( p-- > s ) | 
|  | if( mpi_get_digit( &d, radix, *p ) != 0 ) | 
|  | break; | 
|  |  | 
|  | return( mbedtls_mpi_read_string( X, radix, p + 1 ) ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Write X into an opened file (or stdout if fout == NULL) | 
|  | */ | 
|  | int mbedtls_mpi_write_file( const char *p, const mbedtls_mpi *X, int radix, FILE *fout ) | 
|  | { | 
|  | int ret; | 
|  | size_t n, slen, plen; | 
|  | /* | 
|  | * Buffer should have space for (short) label and decimal formatted MPI, | 
|  | * newline characters and '\0' | 
|  | */ | 
|  | char s[ MBEDTLS_MPI_RW_BUFFER_SIZE ]; | 
|  |  | 
|  | memset( s, 0, sizeof( s ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_write_string( X, radix, s, sizeof( s ) - 2, &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( MBEDTLS_ERR_MPI_FILE_IO_ERROR ); | 
|  | } | 
|  | else | 
|  | mbedtls_printf( "%s%s", p, s ); | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  | #endif /* MBEDTLS_FS_IO */ | 
|  |  | 
|  | /* | 
|  | * Import X from unsigned binary data, big endian | 
|  | */ | 
|  | int mbedtls_mpi_read_binary( mbedtls_mpi *X, const unsigned char *buf, size_t buflen ) | 
|  | { | 
|  | int ret; | 
|  | size_t i, j; | 
|  | size_t const limbs = CHARS_TO_LIMBS( buflen ); | 
|  |  | 
|  | /* Ensure that target MPI has exactly the necessary number of limbs */ | 
|  | if( X->n != limbs ) | 
|  | { | 
|  | mbedtls_mpi_free( X ); | 
|  | mbedtls_mpi_init( X ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( X, limbs ) ); | 
|  | } | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( X, 0 ) ); | 
|  |  | 
|  | for( i = buflen, j = 0; i > 0; i--, j++ ) | 
|  | X->p[j / ciL] |= ((mbedtls_mpi_uint) buf[i - 1]) << ((j % ciL) << 3); | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Export X into unsigned binary data, big endian | 
|  | */ | 
|  | int mbedtls_mpi_write_binary( const mbedtls_mpi *X, unsigned char *buf, size_t buflen ) | 
|  | { | 
|  | size_t i, j, n; | 
|  |  | 
|  | n = mbedtls_mpi_size( X ); | 
|  |  | 
|  | if( buflen < n ) | 
|  | return( MBEDTLS_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 mbedtls_mpi_shift_l( mbedtls_mpi *X, size_t count ) | 
|  | { | 
|  | int ret; | 
|  | size_t i, v0, t1; | 
|  | mbedtls_mpi_uint r0 = 0, r1; | 
|  |  | 
|  | v0 = count / (biL    ); | 
|  | t1 = count & (biL - 1); | 
|  |  | 
|  | i = mbedtls_mpi_bitlen( X ) + count; | 
|  |  | 
|  | if( X->n * biL < i ) | 
|  | MBEDTLS_MPI_CHK( mbedtls_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 mbedtls_mpi_shift_r( mbedtls_mpi *X, size_t count ) | 
|  | { | 
|  | size_t i, v0, v1; | 
|  | mbedtls_mpi_uint r0 = 0, r1; | 
|  |  | 
|  | v0 = count /  biL; | 
|  | v1 = count & (biL - 1); | 
|  |  | 
|  | if( v0 > X->n || ( v0 == X->n && v1 > 0 ) ) | 
|  | return mbedtls_mpi_lset( X, 0 ); | 
|  |  | 
|  | /* | 
|  | * 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 mbedtls_mpi_cmp_abs( const mbedtls_mpi *X, const mbedtls_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 mbedtls_mpi_cmp_mpi( const mbedtls_mpi *X, const mbedtls_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( -Y->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 mbedtls_mpi_cmp_int( const mbedtls_mpi *X, mbedtls_mpi_sint z ) | 
|  | { | 
|  | mbedtls_mpi Y; | 
|  | mbedtls_mpi_uint p[1]; | 
|  |  | 
|  | *p  = ( z < 0 ) ? -z : z; | 
|  | Y.s = ( z < 0 ) ? -1 : 1; | 
|  | Y.n = 1; | 
|  | Y.p = p; | 
|  |  | 
|  | return( mbedtls_mpi_cmp_mpi( X, &Y ) ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Unsigned addition: X = |A| + |B|  (HAC 14.7) | 
|  | */ | 
|  | int mbedtls_mpi_add_abs( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *B ) | 
|  | { | 
|  | int ret; | 
|  | size_t i, j; | 
|  | mbedtls_mpi_uint *o, *p, c, tmp; | 
|  |  | 
|  | if( X == B ) | 
|  | { | 
|  | const mbedtls_mpi *T = A; A = X; B = T; | 
|  | } | 
|  |  | 
|  | if( X != A ) | 
|  | MBEDTLS_MPI_CHK( mbedtls_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; | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( X, j ) ); | 
|  |  | 
|  | o = B->p; p = X->p; c = 0; | 
|  |  | 
|  | /* | 
|  | * tmp is used because it might happen that p == o | 
|  | */ | 
|  | for( i = 0; i < j; i++, o++, p++ ) | 
|  | { | 
|  | tmp= *o; | 
|  | *p +=  c; c  = ( *p <  c ); | 
|  | *p += tmp; c += ( *p < tmp ); | 
|  | } | 
|  |  | 
|  | while( c != 0 ) | 
|  | { | 
|  | if( i >= X->n ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( X, i + 1 ) ); | 
|  | p = X->p + i; | 
|  | } | 
|  |  | 
|  | *p += c; c = ( *p < c ); i++; p++; | 
|  | } | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Helper for mbedtls_mpi subtraction | 
|  | */ | 
|  | static void mpi_sub_hlp( size_t n, mbedtls_mpi_uint *s, mbedtls_mpi_uint *d ) | 
|  | { | 
|  | size_t i; | 
|  | mbedtls_mpi_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; d++; | 
|  | } | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Unsigned subtraction: X = |A| - |B|  (HAC 14.9) | 
|  | */ | 
|  | int mbedtls_mpi_sub_abs( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *B ) | 
|  | { | 
|  | mbedtls_mpi TB; | 
|  | int ret; | 
|  | size_t n; | 
|  |  | 
|  | if( mbedtls_mpi_cmp_abs( A, B ) < 0 ) | 
|  | return( MBEDTLS_ERR_MPI_NEGATIVE_VALUE ); | 
|  |  | 
|  | mbedtls_mpi_init( &TB ); | 
|  |  | 
|  | if( X == B ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &TB, B ) ); | 
|  | B = &TB; | 
|  | } | 
|  |  | 
|  | if( X != A ) | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( X, A ) ); | 
|  |  | 
|  | /* | 
|  | * X should always be positive as a result of unsigned subtractions. | 
|  | */ | 
|  | 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: | 
|  |  | 
|  | mbedtls_mpi_free( &TB ); | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Signed addition: X = A + B | 
|  | */ | 
|  | int mbedtls_mpi_add_mpi( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *B ) | 
|  | { | 
|  | int ret, s = A->s; | 
|  |  | 
|  | if( A->s * B->s < 0 ) | 
|  | { | 
|  | if( mbedtls_mpi_cmp_abs( A, B ) >= 0 ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_abs( X, A, B ) ); | 
|  | X->s =  s; | 
|  | } | 
|  | else | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_abs( X, B, A ) ); | 
|  | X->s = -s; | 
|  | } | 
|  | } | 
|  | else | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_abs( X, A, B ) ); | 
|  | X->s = s; | 
|  | } | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Signed subtraction: X = A - B | 
|  | */ | 
|  | int mbedtls_mpi_sub_mpi( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *B ) | 
|  | { | 
|  | int ret, s = A->s; | 
|  |  | 
|  | if( A->s * B->s > 0 ) | 
|  | { | 
|  | if( mbedtls_mpi_cmp_abs( A, B ) >= 0 ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_abs( X, A, B ) ); | 
|  | X->s =  s; | 
|  | } | 
|  | else | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_abs( X, B, A ) ); | 
|  | X->s = -s; | 
|  | } | 
|  | } | 
|  | else | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_abs( X, A, B ) ); | 
|  | X->s = s; | 
|  | } | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Signed addition: X = A + b | 
|  | */ | 
|  | int mbedtls_mpi_add_int( mbedtls_mpi *X, const mbedtls_mpi *A, mbedtls_mpi_sint b ) | 
|  | { | 
|  | mbedtls_mpi _B; | 
|  | mbedtls_mpi_uint p[1]; | 
|  |  | 
|  | p[0] = ( b < 0 ) ? -b : b; | 
|  | _B.s = ( b < 0 ) ? -1 : 1; | 
|  | _B.n = 1; | 
|  | _B.p = p; | 
|  |  | 
|  | return( mbedtls_mpi_add_mpi( X, A, &_B ) ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Signed subtraction: X = A - b | 
|  | */ | 
|  | int mbedtls_mpi_sub_int( mbedtls_mpi *X, const mbedtls_mpi *A, mbedtls_mpi_sint b ) | 
|  | { | 
|  | mbedtls_mpi _B; | 
|  | mbedtls_mpi_uint p[1]; | 
|  |  | 
|  | p[0] = ( b < 0 ) ? -b : b; | 
|  | _B.s = ( b < 0 ) ? -1 : 1; | 
|  | _B.n = 1; | 
|  | _B.p = p; | 
|  |  | 
|  | return( mbedtls_mpi_sub_mpi( X, A, &_B ) ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Helper for mbedtls_mpi multiplication | 
|  | */ | 
|  | static | 
|  | #if defined(__APPLE__) && defined(__arm__) | 
|  | /* | 
|  | * Apple LLVM version 4.2 (clang-425.0.24) (based on LLVM 3.2svn) | 
|  | * appears to need this to prevent bad ARM code generation at -O3. | 
|  | */ | 
|  | __attribute__ ((noinline)) | 
|  | #endif | 
|  | void mpi_mul_hlp( size_t i, mbedtls_mpi_uint *s, mbedtls_mpi_uint *d, mbedtls_mpi_uint b ) | 
|  | { | 
|  | mbedtls_mpi_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 /* MULADDC_HUIT */ | 
|  | 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 /* MULADDC_HUIT */ | 
|  |  | 
|  | t++; | 
|  |  | 
|  | do { | 
|  | *d += c; c = ( *d < c ); d++; | 
|  | } | 
|  | while( c != 0 ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Baseline multiplication: X = A * B  (HAC 14.12) | 
|  | */ | 
|  | int mbedtls_mpi_mul_mpi( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *B ) | 
|  | { | 
|  | int ret; | 
|  | size_t i, j; | 
|  | mbedtls_mpi TA, TB; | 
|  |  | 
|  | mbedtls_mpi_init( &TA ); mbedtls_mpi_init( &TB ); | 
|  |  | 
|  | if( X == A ) { MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &TA, A ) ); A = &TA; } | 
|  | if( X == B ) { MBEDTLS_MPI_CHK( mbedtls_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; | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( X, i + j ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( X, 0 ) ); | 
|  |  | 
|  | for( ; j > 0; j-- ) | 
|  | mpi_mul_hlp( i, A->p, X->p + j - 1, B->p[j - 1] ); | 
|  |  | 
|  | X->s = A->s * B->s; | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | mbedtls_mpi_free( &TB ); mbedtls_mpi_free( &TA ); | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Baseline multiplication: X = A * b | 
|  | */ | 
|  | int mbedtls_mpi_mul_int( mbedtls_mpi *X, const mbedtls_mpi *A, mbedtls_mpi_uint b ) | 
|  | { | 
|  | mbedtls_mpi _B; | 
|  | mbedtls_mpi_uint p[1]; | 
|  |  | 
|  | _B.s = 1; | 
|  | _B.n = 1; | 
|  | _B.p = p; | 
|  | p[0] = b; | 
|  |  | 
|  | return( mbedtls_mpi_mul_mpi( X, A, &_B ) ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Unsigned integer divide - double mbedtls_mpi_uint dividend, u1/u0, and | 
|  | * mbedtls_mpi_uint divisor, d | 
|  | */ | 
|  | static mbedtls_mpi_uint mbedtls_int_div_int( mbedtls_mpi_uint u1, | 
|  | mbedtls_mpi_uint u0, mbedtls_mpi_uint d, mbedtls_mpi_uint *r ) | 
|  | { | 
|  | #if defined(MBEDTLS_HAVE_UDBL) | 
|  | mbedtls_t_udbl dividend, quotient; | 
|  | #else | 
|  | const mbedtls_mpi_uint radix = (mbedtls_mpi_uint) 1 << biH; | 
|  | const mbedtls_mpi_uint uint_halfword_mask = ( (mbedtls_mpi_uint) 1 << biH ) - 1; | 
|  | mbedtls_mpi_uint d0, d1, q0, q1, rAX, r0, quotient; | 
|  | mbedtls_mpi_uint u0_msw, u0_lsw; | 
|  | size_t s; | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * Check for overflow | 
|  | */ | 
|  | if( 0 == d || u1 >= d ) | 
|  | { | 
|  | if (r != NULL) *r = ~0; | 
|  |  | 
|  | return ( ~0 ); | 
|  | } | 
|  |  | 
|  | #if defined(MBEDTLS_HAVE_UDBL) | 
|  | dividend  = (mbedtls_t_udbl) u1 << biL; | 
|  | dividend |= (mbedtls_t_udbl) u0; | 
|  | quotient = dividend / d; | 
|  | if( quotient > ( (mbedtls_t_udbl) 1 << biL ) - 1 ) | 
|  | quotient = ( (mbedtls_t_udbl) 1 << biL ) - 1; | 
|  |  | 
|  | if( r != NULL ) | 
|  | *r = (mbedtls_mpi_uint)( dividend - (quotient * d ) ); | 
|  |  | 
|  | return (mbedtls_mpi_uint) quotient; | 
|  | #else | 
|  |  | 
|  | /* | 
|  | * Algorithm D, Section 4.3.1 - The Art of Computer Programming | 
|  | *   Vol. 2 - Seminumerical Algorithms, Knuth | 
|  | */ | 
|  |  | 
|  | /* | 
|  | * Normalize the divisor, d, and dividend, u0, u1 | 
|  | */ | 
|  | s = mbedtls_clz( d ); | 
|  | d = d << s; | 
|  |  | 
|  | u1 = u1 << s; | 
|  | u1 |= ( u0 >> ( biL - s ) ) & ( -(mbedtls_mpi_sint)s >> ( biL - 1 ) ); | 
|  | u0 =  u0 << s; | 
|  |  | 
|  | d1 = d >> biH; | 
|  | d0 = d & uint_halfword_mask; | 
|  |  | 
|  | u0_msw = u0 >> biH; | 
|  | u0_lsw = u0 & uint_halfword_mask; | 
|  |  | 
|  | /* | 
|  | * Find the first quotient and remainder | 
|  | */ | 
|  | q1 = u1 / d1; | 
|  | r0 = u1 - d1 * q1; | 
|  |  | 
|  | while( q1 >= radix || ( q1 * d0 > radix * r0 + u0_msw ) ) | 
|  | { | 
|  | q1 -= 1; | 
|  | r0 += d1; | 
|  |  | 
|  | if ( r0 >= radix ) break; | 
|  | } | 
|  |  | 
|  | rAX = ( u1 * radix ) + ( u0_msw - q1 * d ); | 
|  | q0 = rAX / d1; | 
|  | r0 = rAX - q0 * d1; | 
|  |  | 
|  | while( q0 >= radix || ( q0 * d0 > radix * r0 + u0_lsw ) ) | 
|  | { | 
|  | q0 -= 1; | 
|  | r0 += d1; | 
|  |  | 
|  | if ( r0 >= radix ) break; | 
|  | } | 
|  |  | 
|  | if (r != NULL) | 
|  | *r = ( rAX * radix + u0_lsw - q0 * d ) >> s; | 
|  |  | 
|  | quotient = q1 * radix + q0; | 
|  |  | 
|  | return quotient; | 
|  | #endif | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Division by mbedtls_mpi: A = Q * B + R  (HAC 14.20) | 
|  | */ | 
|  | int mbedtls_mpi_div_mpi( mbedtls_mpi *Q, mbedtls_mpi *R, const mbedtls_mpi *A, const mbedtls_mpi *B ) | 
|  | { | 
|  | int ret; | 
|  | size_t i, n, t, k; | 
|  | mbedtls_mpi X, Y, Z, T1, T2; | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( B, 0 ) == 0 ) | 
|  | return( MBEDTLS_ERR_MPI_DIVISION_BY_ZERO ); | 
|  |  | 
|  | mbedtls_mpi_init( &X ); mbedtls_mpi_init( &Y ); mbedtls_mpi_init( &Z ); | 
|  | mbedtls_mpi_init( &T1 ); mbedtls_mpi_init( &T2 ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_abs( A, B ) < 0 ) | 
|  | { | 
|  | if( Q != NULL ) MBEDTLS_MPI_CHK( mbedtls_mpi_lset( Q, 0 ) ); | 
|  | if( R != NULL ) MBEDTLS_MPI_CHK( mbedtls_mpi_copy( R, A ) ); | 
|  | return( 0 ); | 
|  | } | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &X, A ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &Y, B ) ); | 
|  | X.s = Y.s = 1; | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( &Z, A->n + 2 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &Z,  0 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( &T1, 2 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( &T2, 3 ) ); | 
|  |  | 
|  | k = mbedtls_mpi_bitlen( &Y ) % biL; | 
|  | if( k < biL - 1 ) | 
|  | { | 
|  | k = biL - 1 - k; | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_l( &X, k ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_l( &Y, k ) ); | 
|  | } | 
|  | else k = 0; | 
|  |  | 
|  | n = X.n - 1; | 
|  | t = Y.n - 1; | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_l( &Y, biL * ( n - t ) ) ); | 
|  |  | 
|  | while( mbedtls_mpi_cmp_mpi( &X, &Y ) >= 0 ) | 
|  | { | 
|  | Z.p[n - t]++; | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &X, &X, &Y ) ); | 
|  | } | 
|  | MBEDTLS_MPI_CHK( mbedtls_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 | 
|  | { | 
|  | Z.p[i - t - 1] = mbedtls_int_div_int( X.p[i], X.p[i - 1], | 
|  | Y.p[t], NULL); | 
|  | } | 
|  |  | 
|  | Z.p[i - t - 1]++; | 
|  | do | 
|  | { | 
|  | Z.p[i - t - 1]--; | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &T1, 0 ) ); | 
|  | T1.p[0] = ( t < 1 ) ? 0 : Y.p[t - 1]; | 
|  | T1.p[1] = Y.p[t]; | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_int( &T1, &T1, Z.p[i - t - 1] ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_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( mbedtls_mpi_cmp_mpi( &T1, &T2 ) > 0 ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_int( &T1, &Y, Z.p[i - t - 1] ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_l( &T1,  biL * ( i - t - 1 ) ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &X, &X, &T1 ) ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( &X, 0 ) < 0 ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &T1, &Y ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_l( &T1, biL * ( i - t - 1 ) ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &X, &X, &T1 ) ); | 
|  | Z.p[i - t - 1]--; | 
|  | } | 
|  | } | 
|  |  | 
|  | if( Q != NULL ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( Q, &Z ) ); | 
|  | Q->s = A->s * B->s; | 
|  | } | 
|  |  | 
|  | if( R != NULL ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &X, k ) ); | 
|  | X.s = A->s; | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( R, &X ) ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( R, 0 ) == 0 ) | 
|  | R->s = 1; | 
|  | } | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | mbedtls_mpi_free( &X ); mbedtls_mpi_free( &Y ); mbedtls_mpi_free( &Z ); | 
|  | mbedtls_mpi_free( &T1 ); mbedtls_mpi_free( &T2 ); | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Division by int: A = Q * b + R | 
|  | */ | 
|  | int mbedtls_mpi_div_int( mbedtls_mpi *Q, mbedtls_mpi *R, const mbedtls_mpi *A, mbedtls_mpi_sint b ) | 
|  | { | 
|  | mbedtls_mpi _B; | 
|  | mbedtls_mpi_uint p[1]; | 
|  |  | 
|  | p[0] = ( b < 0 ) ? -b : b; | 
|  | _B.s = ( b < 0 ) ? -1 : 1; | 
|  | _B.n = 1; | 
|  | _B.p = p; | 
|  |  | 
|  | return( mbedtls_mpi_div_mpi( Q, R, A, &_B ) ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Modulo: R = A mod B | 
|  | */ | 
|  | int mbedtls_mpi_mod_mpi( mbedtls_mpi *R, const mbedtls_mpi *A, const mbedtls_mpi *B ) | 
|  | { | 
|  | int ret; | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( B, 0 ) < 0 ) | 
|  | return( MBEDTLS_ERR_MPI_NEGATIVE_VALUE ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_div_mpi( NULL, R, A, B ) ); | 
|  |  | 
|  | while( mbedtls_mpi_cmp_int( R, 0 ) < 0 ) | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( R, R, B ) ); | 
|  |  | 
|  | while( mbedtls_mpi_cmp_mpi( R, B ) >= 0 ) | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( R, R, B ) ); | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Modulo: r = A mod b | 
|  | */ | 
|  | int mbedtls_mpi_mod_int( mbedtls_mpi_uint *r, const mbedtls_mpi *A, mbedtls_mpi_sint b ) | 
|  | { | 
|  | size_t i; | 
|  | mbedtls_mpi_uint x, y, z; | 
|  |  | 
|  | if( b == 0 ) | 
|  | return( MBEDTLS_ERR_MPI_DIVISION_BY_ZERO ); | 
|  |  | 
|  | if( b < 0 ) | 
|  | return( MBEDTLS_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( mbedtls_mpi_uint *mm, const mbedtls_mpi *N ) | 
|  | { | 
|  | mbedtls_mpi_uint x, m0 = N->p[0]; | 
|  | unsigned int i; | 
|  |  | 
|  | x  = m0; | 
|  | x += ( ( m0 + 2 ) & 4 ) << 1; | 
|  |  | 
|  | for( i = biL; i >= 8; i /= 2 ) | 
|  | x *= ( 2 - ( m0 * x ) ); | 
|  |  | 
|  | *mm = ~x + 1; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Montgomery multiplication: A = A * B * R^-1 mod N  (HAC 14.36) | 
|  | */ | 
|  | static int mpi_montmul( mbedtls_mpi *A, const mbedtls_mpi *B, const mbedtls_mpi *N, mbedtls_mpi_uint mm, | 
|  | const mbedtls_mpi *T ) | 
|  | { | 
|  | size_t i, n, m; | 
|  | mbedtls_mpi_uint u0, u1, *d; | 
|  |  | 
|  | if( T->n < N->n + 1 || T->p == NULL ) | 
|  | return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA ); | 
|  |  | 
|  | 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( mbedtls_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 ); | 
|  |  | 
|  | return( 0 ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Montgomery reduction: A = A * R^-1 mod N | 
|  | */ | 
|  | static int mpi_montred( mbedtls_mpi *A, const mbedtls_mpi *N, mbedtls_mpi_uint mm, const mbedtls_mpi *T ) | 
|  | { | 
|  | mbedtls_mpi_uint z = 1; | 
|  | mbedtls_mpi U; | 
|  |  | 
|  | U.n = U.s = (int) z; | 
|  | U.p = &z; | 
|  |  | 
|  | return( mpi_montmul( A, &U, N, mm, T ) ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Sliding-window exponentiation: X = A^E mod N  (HAC 14.85) | 
|  | */ | 
|  | int mbedtls_mpi_exp_mod( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *E, const mbedtls_mpi *N, mbedtls_mpi *_RR ) | 
|  | { | 
|  | int ret; | 
|  | size_t wbits, wsize, one = 1; | 
|  | size_t i, j, nblimbs; | 
|  | size_t bufsize, nbits; | 
|  | mbedtls_mpi_uint ei, mm, state; | 
|  | mbedtls_mpi RR, T, W[ 2 << MBEDTLS_MPI_WINDOW_SIZE ], Apos; | 
|  | int neg; | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( N, 0 ) <= 0 || ( N->p[0] & 1 ) == 0 ) | 
|  | return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( E, 0 ) < 0 ) | 
|  | return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA ); | 
|  |  | 
|  | /* | 
|  | * Init temps and window size | 
|  | */ | 
|  | mpi_montg_init( &mm, N ); | 
|  | mbedtls_mpi_init( &RR ); mbedtls_mpi_init( &T ); | 
|  | mbedtls_mpi_init( &Apos ); | 
|  | memset( W, 0, sizeof( W ) ); | 
|  |  | 
|  | i = mbedtls_mpi_bitlen( E ); | 
|  |  | 
|  | wsize = ( i > 671 ) ? 6 : ( i > 239 ) ? 5 : | 
|  | ( i >  79 ) ? 4 : ( i >  23 ) ? 3 : 1; | 
|  |  | 
|  | if( wsize > MBEDTLS_MPI_WINDOW_SIZE ) | 
|  | wsize = MBEDTLS_MPI_WINDOW_SIZE; | 
|  |  | 
|  | j = N->n + 1; | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( X, j ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( &W[1],  j ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( &T, j * 2 ) ); | 
|  |  | 
|  | /* | 
|  | * Compensate for negative A (and correct at the end) | 
|  | */ | 
|  | neg = ( A->s == -1 ); | 
|  | if( neg ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &Apos, A ) ); | 
|  | Apos.s = 1; | 
|  | A = &Apos; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * If 1st call, pre-compute R^2 mod N | 
|  | */ | 
|  | if( _RR == NULL || _RR->p == NULL ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &RR, 1 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_l( &RR, N->n * 2 * biL ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &RR, &RR, N ) ); | 
|  |  | 
|  | if( _RR != NULL ) | 
|  | memcpy( _RR, &RR, sizeof( mbedtls_mpi ) ); | 
|  | } | 
|  | else | 
|  | memcpy( &RR, _RR, sizeof( mbedtls_mpi ) ); | 
|  |  | 
|  | /* | 
|  | * W[1] = A * R^2 * R^-1 mod N = A * R mod N | 
|  | */ | 
|  | if( mbedtls_mpi_cmp_mpi( A, N ) >= 0 ) | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &W[1], A, N ) ); | 
|  | else | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &W[1], A ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mpi_montmul( &W[1], &RR, N, mm, &T ) ); | 
|  |  | 
|  | /* | 
|  | * X = R^2 * R^-1 mod N = R mod N | 
|  | */ | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( X, &RR ) ); | 
|  | MBEDTLS_MPI_CHK( mpi_montred( X, N, mm, &T ) ); | 
|  |  | 
|  | if( wsize > 1 ) | 
|  | { | 
|  | /* | 
|  | * W[1 << (wsize - 1)] = W[1] ^ (wsize - 1) | 
|  | */ | 
|  | j =  one << ( wsize - 1 ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( &W[j], N->n + 1 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &W[j], &W[1]    ) ); | 
|  |  | 
|  | for( i = 0; i < wsize - 1; i++ ) | 
|  | MBEDTLS_MPI_CHK( mpi_montmul( &W[j], &W[j], N, mm, &T ) ); | 
|  |  | 
|  | /* | 
|  | * W[i] = W[i - 1] * W[1] | 
|  | */ | 
|  | for( i = j + 1; i < ( one << wsize ); i++ ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_grow( &W[i], N->n + 1 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &W[i], &W[i - 1] ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( 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; | 
|  |  | 
|  | nblimbs--; | 
|  |  | 
|  | bufsize = sizeof( mbedtls_mpi_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 | 
|  | */ | 
|  | MBEDTLS_MPI_CHK( 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++ ) | 
|  | MBEDTLS_MPI_CHK( mpi_montmul( X, X, N, mm, &T ) ); | 
|  |  | 
|  | /* | 
|  | * X = X * W[wbits] R^-1 mod N | 
|  | */ | 
|  | MBEDTLS_MPI_CHK( mpi_montmul( X, &W[wbits], N, mm, &T ) ); | 
|  |  | 
|  | state--; | 
|  | nbits = 0; | 
|  | wbits = 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | /* | 
|  | * process the remaining bits | 
|  | */ | 
|  | for( i = 0; i < nbits; i++ ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mpi_montmul( X, X, N, mm, &T ) ); | 
|  |  | 
|  | wbits <<= 1; | 
|  |  | 
|  | if( ( wbits & ( one << wsize ) ) != 0 ) | 
|  | MBEDTLS_MPI_CHK( mpi_montmul( X, &W[1], N, mm, &T ) ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * X = A^E * R * R^-1 mod N = A^E mod N | 
|  | */ | 
|  | MBEDTLS_MPI_CHK( mpi_montred( X, N, mm, &T ) ); | 
|  |  | 
|  | if( neg && E->n != 0 && ( E->p[0] & 1 ) != 0 ) | 
|  | { | 
|  | X->s = -1; | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( X, N, X ) ); | 
|  | } | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | for( i = ( one << ( wsize - 1 ) ); i < ( one << wsize ); i++ ) | 
|  | mbedtls_mpi_free( &W[i] ); | 
|  |  | 
|  | mbedtls_mpi_free( &W[1] ); mbedtls_mpi_free( &T ); mbedtls_mpi_free( &Apos ); | 
|  |  | 
|  | if( _RR == NULL || _RR->p == NULL ) | 
|  | mbedtls_mpi_free( &RR ); | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Greatest common divisor: G = gcd(A, B)  (HAC 14.54) | 
|  | */ | 
|  | int mbedtls_mpi_gcd( mbedtls_mpi *G, const mbedtls_mpi *A, const mbedtls_mpi *B ) | 
|  | { | 
|  | int ret; | 
|  | size_t lz, lzt; | 
|  | mbedtls_mpi TG, TA, TB; | 
|  |  | 
|  | mbedtls_mpi_init( &TG ); mbedtls_mpi_init( &TA ); mbedtls_mpi_init( &TB ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &TA, A ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &TB, B ) ); | 
|  |  | 
|  | lz = mbedtls_mpi_lsb( &TA ); | 
|  | lzt = mbedtls_mpi_lsb( &TB ); | 
|  |  | 
|  | if( lzt < lz ) | 
|  | lz = lzt; | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &TA, lz ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &TB, lz ) ); | 
|  |  | 
|  | TA.s = TB.s = 1; | 
|  |  | 
|  | while( mbedtls_mpi_cmp_int( &TA, 0 ) != 0 ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &TA, mbedtls_mpi_lsb( &TA ) ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &TB, mbedtls_mpi_lsb( &TB ) ) ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_mpi( &TA, &TB ) >= 0 ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_abs( &TA, &TA, &TB ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &TA, 1 ) ); | 
|  | } | 
|  | else | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_abs( &TB, &TB, &TA ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &TB, 1 ) ); | 
|  | } | 
|  | } | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_l( &TB, lz ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( G, &TB ) ); | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | mbedtls_mpi_free( &TG ); mbedtls_mpi_free( &TA ); mbedtls_mpi_free( &TB ); | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Fill X with size bytes of random. | 
|  | * | 
|  | * Use a temporary bytes representation to make sure the result is the same | 
|  | * regardless of the platform endianness (useful when f_rng is actually | 
|  | * deterministic, eg for tests). | 
|  | */ | 
|  | int mbedtls_mpi_fill_random( mbedtls_mpi *X, size_t size, | 
|  | int (*f_rng)(void *, unsigned char *, size_t), | 
|  | void *p_rng ) | 
|  | { | 
|  | int ret; | 
|  | unsigned char buf[MBEDTLS_MPI_MAX_SIZE]; | 
|  |  | 
|  | if( size > MBEDTLS_MPI_MAX_SIZE ) | 
|  | return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( f_rng( p_rng, buf, size ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( X, buf, size ) ); | 
|  |  | 
|  | cleanup: | 
|  | mbedtls_platform_zeroize( buf, sizeof( buf ) ); | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Modular inverse: X = A^-1 mod N  (HAC 14.61 / 14.64) | 
|  | */ | 
|  | int mbedtls_mpi_inv_mod( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *N ) | 
|  | { | 
|  | int ret; | 
|  | mbedtls_mpi G, TA, TU, U1, U2, TB, TV, V1, V2; | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( N, 1 ) <= 0 ) | 
|  | return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA ); | 
|  |  | 
|  | mbedtls_mpi_init( &TA ); mbedtls_mpi_init( &TU ); mbedtls_mpi_init( &U1 ); mbedtls_mpi_init( &U2 ); | 
|  | mbedtls_mpi_init( &G ); mbedtls_mpi_init( &TB ); mbedtls_mpi_init( &TV ); | 
|  | mbedtls_mpi_init( &V1 ); mbedtls_mpi_init( &V2 ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_gcd( &G, A, N ) ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( &G, 1 ) != 0 ) | 
|  | { | 
|  | ret = MBEDTLS_ERR_MPI_NOT_ACCEPTABLE; | 
|  | goto cleanup; | 
|  | } | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &TA, A, N ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &TU, &TA ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &TB, N ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &TV, N ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &U1, 1 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &U2, 0 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &V1, 0 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &V2, 1 ) ); | 
|  |  | 
|  | do | 
|  | { | 
|  | while( ( TU.p[0] & 1 ) == 0 ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &TU, 1 ) ); | 
|  |  | 
|  | if( ( U1.p[0] & 1 ) != 0 || ( U2.p[0] & 1 ) != 0 ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &U1, &U1, &TB ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &U2, &U2, &TA ) ); | 
|  | } | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &U1, 1 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &U2, 1 ) ); | 
|  | } | 
|  |  | 
|  | while( ( TV.p[0] & 1 ) == 0 ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &TV, 1 ) ); | 
|  |  | 
|  | if( ( V1.p[0] & 1 ) != 0 || ( V2.p[0] & 1 ) != 0 ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &V1, &V1, &TB ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &V2, &V2, &TA ) ); | 
|  | } | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &V1, 1 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &V2, 1 ) ); | 
|  | } | 
|  |  | 
|  | if( mbedtls_mpi_cmp_mpi( &TU, &TV ) >= 0 ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &TU, &TU, &TV ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &U1, &U1, &V1 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &U2, &U2, &V2 ) ); | 
|  | } | 
|  | else | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &TV, &TV, &TU ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &V1, &V1, &U1 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &V2, &V2, &U2 ) ); | 
|  | } | 
|  | } | 
|  | while( mbedtls_mpi_cmp_int( &TU, 0 ) != 0 ); | 
|  |  | 
|  | while( mbedtls_mpi_cmp_int( &V1, 0 ) < 0 ) | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &V1, &V1, N ) ); | 
|  |  | 
|  | while( mbedtls_mpi_cmp_mpi( &V1, N ) >= 0 ) | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &V1, &V1, N ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( X, &V1 ) ); | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | mbedtls_mpi_free( &TA ); mbedtls_mpi_free( &TU ); mbedtls_mpi_free( &U1 ); mbedtls_mpi_free( &U2 ); | 
|  | mbedtls_mpi_free( &G ); mbedtls_mpi_free( &TB ); mbedtls_mpi_free( &TV ); | 
|  | mbedtls_mpi_free( &V1 ); mbedtls_mpi_free( &V2 ); | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | #if defined(MBEDTLS_GENPRIME) | 
|  |  | 
|  | 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 | 
|  | }; | 
|  |  | 
|  | /* | 
|  | * Small divisors test (X must be positive) | 
|  | * | 
|  | * Return values: | 
|  | * 0: no small factor (possible prime, more tests needed) | 
|  | * 1: certain prime | 
|  | * MBEDTLS_ERR_MPI_NOT_ACCEPTABLE: certain non-prime | 
|  | * other negative: error | 
|  | */ | 
|  | static int mpi_check_small_factors( const mbedtls_mpi *X ) | 
|  | { | 
|  | int ret = 0; | 
|  | size_t i; | 
|  | mbedtls_mpi_uint r; | 
|  |  | 
|  | if( ( X->p[0] & 1 ) == 0 ) | 
|  | return( MBEDTLS_ERR_MPI_NOT_ACCEPTABLE ); | 
|  |  | 
|  | for( i = 0; small_prime[i] > 0; i++ ) | 
|  | { | 
|  | if( mbedtls_mpi_cmp_int( X, small_prime[i] ) <= 0 ) | 
|  | return( 1 ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_mod_int( &r, X, small_prime[i] ) ); | 
|  |  | 
|  | if( r == 0 ) | 
|  | return( MBEDTLS_ERR_MPI_NOT_ACCEPTABLE ); | 
|  | } | 
|  |  | 
|  | cleanup: | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Miller-Rabin pseudo-primality test  (HAC 4.24) | 
|  | */ | 
|  | static int mpi_miller_rabin( const mbedtls_mpi *X, | 
|  | int (*f_rng)(void *, unsigned char *, size_t), | 
|  | void *p_rng ) | 
|  | { | 
|  | int ret, count; | 
|  | size_t i, j, k, n, s; | 
|  | mbedtls_mpi W, R, T, A, RR; | 
|  |  | 
|  | mbedtls_mpi_init( &W ); mbedtls_mpi_init( &R ); mbedtls_mpi_init( &T ); mbedtls_mpi_init( &A ); | 
|  | mbedtls_mpi_init( &RR ); | 
|  |  | 
|  | /* | 
|  | * W = |X| - 1 | 
|  | * R = W >> lsb( W ) | 
|  | */ | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &W, X, 1 ) ); | 
|  | s = mbedtls_mpi_lsb( &W ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &R, &W ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &R, s ) ); | 
|  |  | 
|  | i = mbedtls_mpi_bitlen( 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 | 
|  | */ | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &A, X->n * ciL, f_rng, p_rng ) ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_mpi( &A, &W ) >= 0 ) | 
|  | { | 
|  | j = mbedtls_mpi_bitlen( &A ) - mbedtls_mpi_bitlen( &W ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &A, j + 1 ) ); | 
|  | } | 
|  | A.p[0] |= 3; | 
|  |  | 
|  | count = 0; | 
|  | do { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &A, X->n * ciL, f_rng, p_rng ) ); | 
|  |  | 
|  | j = mbedtls_mpi_bitlen( &A ); | 
|  | k = mbedtls_mpi_bitlen( &W ); | 
|  | if (j > k) { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &A, j - k ) ); | 
|  | } | 
|  |  | 
|  | if (count++ > 30) { | 
|  | return MBEDTLS_ERR_MPI_NOT_ACCEPTABLE; | 
|  | } | 
|  |  | 
|  | } while ( mbedtls_mpi_cmp_mpi( &A, &W ) >= 0 || | 
|  | mbedtls_mpi_cmp_int( &A, 1 )  <= 0    ); | 
|  |  | 
|  | /* | 
|  | * A = A^R mod |X| | 
|  | */ | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &A, &A, &R, X, &RR ) ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_mpi( &A, &W ) == 0 || | 
|  | mbedtls_mpi_cmp_int( &A,  1 ) == 0 ) | 
|  | continue; | 
|  |  | 
|  | j = 1; | 
|  | while( j < s && mbedtls_mpi_cmp_mpi( &A, &W ) != 0 ) | 
|  | { | 
|  | /* | 
|  | * A = A * A mod |X| | 
|  | */ | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &T, &A, &A ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &A, &T, X  ) ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( &A, 1 ) == 0 ) | 
|  | break; | 
|  |  | 
|  | j++; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * not prime if A != |X| - 1 or A == 1 | 
|  | */ | 
|  | if( mbedtls_mpi_cmp_mpi( &A, &W ) != 0 || | 
|  | mbedtls_mpi_cmp_int( &A,  1 ) == 0 ) | 
|  | { | 
|  | ret = MBEDTLS_ERR_MPI_NOT_ACCEPTABLE; | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | cleanup: | 
|  | mbedtls_mpi_free( &W ); mbedtls_mpi_free( &R ); mbedtls_mpi_free( &T ); mbedtls_mpi_free( &A ); | 
|  | mbedtls_mpi_free( &RR ); | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Pseudo-primality test: small factors, then Miller-Rabin | 
|  | */ | 
|  | int mbedtls_mpi_is_prime( const mbedtls_mpi *X, | 
|  | int (*f_rng)(void *, unsigned char *, size_t), | 
|  | void *p_rng ) | 
|  | { | 
|  | int ret; | 
|  | mbedtls_mpi XX; | 
|  |  | 
|  | XX.s = 1; | 
|  | XX.n = X->n; | 
|  | XX.p = X->p; | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( &XX, 0 ) == 0 || | 
|  | mbedtls_mpi_cmp_int( &XX, 1 ) == 0 ) | 
|  | return( MBEDTLS_ERR_MPI_NOT_ACCEPTABLE ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( &XX, 2 ) == 0 ) | 
|  | return( 0 ); | 
|  |  | 
|  | if( ( ret = mpi_check_small_factors( &XX ) ) != 0 ) | 
|  | { | 
|  | if( ret == 1 ) | 
|  | return( 0 ); | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | return( mpi_miller_rabin( &XX, f_rng, p_rng ) ); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Prime number generation | 
|  | * | 
|  | * If dh_flag is 0 and nbits is at least 1024, then the procedure | 
|  | * follows the RSA probably-prime generation method of FIPS 186-4. | 
|  | * NB. FIPS 186-4 only allows the specific bit lengths of 1024 and 1536. | 
|  | */ | 
|  | int mbedtls_mpi_gen_prime( mbedtls_mpi *X, size_t nbits, int dh_flag, | 
|  | int (*f_rng)(void *, unsigned char *, size_t), | 
|  | void *p_rng ) | 
|  | { | 
|  | #ifdef MBEDTLS_HAVE_INT64 | 
|  | // ceil(2^63.5) | 
|  | #define CEIL_MAXUINT_DIV_SQRT2 0xb504f333f9de6485ULL | 
|  | #else | 
|  | // ceil(2^31.5) | 
|  | #define CEIL_MAXUINT_DIV_SQRT2 0xb504f334U | 
|  | #endif | 
|  | int ret = MBEDTLS_ERR_MPI_NOT_ACCEPTABLE; | 
|  | size_t k, n; | 
|  | mbedtls_mpi_uint r; | 
|  | mbedtls_mpi Y; | 
|  |  | 
|  | if( nbits < 3 || nbits > MBEDTLS_MPI_MAX_BITS ) | 
|  | return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA ); | 
|  |  | 
|  | mbedtls_mpi_init( &Y ); | 
|  |  | 
|  | n = BITS_TO_LIMBS( nbits ); | 
|  |  | 
|  | while( 1 ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( X, n * ciL, f_rng, p_rng ) ); | 
|  | /* make sure generated number is at least (nbits-1)+0.5 bits (FIPS 186-4 §B.3.3 steps 4.4, 5.5) */ | 
|  | if( X->p[n-1] < CEIL_MAXUINT_DIV_SQRT2 ) continue; | 
|  |  | 
|  | k = n * biL; | 
|  | if( k > nbits ) MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( X, k - nbits ) ); | 
|  | X->p[0] |= 1; | 
|  |  | 
|  | if( dh_flag == 0 ) | 
|  | { | 
|  | ret = mbedtls_mpi_is_prime( X, f_rng, p_rng ); | 
|  |  | 
|  | if( ret != MBEDTLS_ERR_MPI_NOT_ACCEPTABLE ) | 
|  | goto cleanup; | 
|  | } | 
|  | else | 
|  | { | 
|  | /* | 
|  | * An necessary condition for Y and X = 2Y + 1 to be prime | 
|  | * is X = 2 mod 3 (which is equivalent to Y = 2 mod 3). | 
|  | * Make sure it is satisfied, while keeping X = 3 mod 4 | 
|  | */ | 
|  |  | 
|  | X->p[0] |= 2; | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_mod_int( &r, X, 3 ) ); | 
|  | if( r == 0 ) | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_int( X, X, 8 ) ); | 
|  | else if( r == 1 ) | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_int( X, X, 4 ) ); | 
|  |  | 
|  | /* Set Y = (X-1) / 2, which is X / 2 because X is odd */ | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &Y, X ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_shift_r( &Y, 1 ) ); | 
|  |  | 
|  | while( 1 ) | 
|  | { | 
|  | /* | 
|  | * First, check small factors for X and Y | 
|  | * before doing Miller-Rabin on any of them | 
|  | */ | 
|  | if( ( ret = mpi_check_small_factors(  X         ) ) == 0 && | 
|  | ( ret = mpi_check_small_factors( &Y         ) ) == 0 && | 
|  | ( ret = mpi_miller_rabin(  X, f_rng, p_rng  ) ) == 0 && | 
|  | ( ret = mpi_miller_rabin( &Y, f_rng, p_rng  ) ) == 0 ) | 
|  | goto cleanup; | 
|  |  | 
|  | if( ret != MBEDTLS_ERR_MPI_NOT_ACCEPTABLE ) | 
|  | goto cleanup; | 
|  |  | 
|  | /* | 
|  | * Next candidates. We want to preserve Y = (X-1) / 2 and | 
|  | * Y = 1 mod 2 and Y = 2 mod 3 (eq X = 3 mod 4 and X = 2 mod 3) | 
|  | * so up Y by 6 and X by 12. | 
|  | */ | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_int(  X,  X, 12 ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_add_int( &Y, &Y, 6  ) ); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | mbedtls_mpi_free( &Y ); | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | #endif /* MBEDTLS_GENPRIME */ | 
|  |  | 
|  | #if defined(MBEDTLS_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 mbedtls_mpi_self_test( int verbose ) | 
|  | { | 
|  | int ret, i; | 
|  | mbedtls_mpi A, E, N, X, Y, U, V; | 
|  |  | 
|  | mbedtls_mpi_init( &A ); mbedtls_mpi_init( &E ); mbedtls_mpi_init( &N ); mbedtls_mpi_init( &X ); | 
|  | mbedtls_mpi_init( &Y ); mbedtls_mpi_init( &U ); mbedtls_mpi_init( &V ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &A, 16, | 
|  | "EFE021C2645FD1DC586E69184AF4A31E" \ | 
|  | "D5F53E93B5F123FA41680867BA110131" \ | 
|  | "944FE7952E2517337780CB0DB80E61AA" \ | 
|  | "E7C8DDC6C5C6AADEB34EB38A2F40D5E6" ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &E, 16, | 
|  | "B2E7EFD37075B9F03FF989C7C5051C20" \ | 
|  | "34D2A323810251127E7BF8625A4F49A5" \ | 
|  | "F3E27F4DA8BD59C47D6DAABA4C8127BD" \ | 
|  | "5B5C25763222FEFCCFC38B832366C29E" ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &N, 16, | 
|  | "0066A198186C18C10B2F5ED9B522752A" \ | 
|  | "9830B69916E535C8F047518A889A43A5" \ | 
|  | "94B6BED27A168D31D4A52F88925AA8F5" ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &X, &A, &N ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &U, 16, | 
|  | "602AB7ECA597A3D6B56FF9829A5E8B85" \ | 
|  | "9E857EA95A03512E2BAE7391688D264A" \ | 
|  | "A5663B0341DB9CCFD2C4C5F421FEC814" \ | 
|  | "8001B72E848A38CAE1C65F78E56ABDEF" \ | 
|  | "E12D3C039B8A02D6BE593F0BBBDA56F1" \ | 
|  | "ECF677152EF804370C1A305CAF3B5BF1" \ | 
|  | "30879B56C61DE584A0F53A2447A51E" ) ); | 
|  |  | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "  MPI test #1 (mul_mpi): " ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_mpi( &X, &U ) != 0 ) | 
|  | { | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "failed\n" ); | 
|  |  | 
|  | ret = 1; | 
|  | goto cleanup; | 
|  | } | 
|  |  | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "passed\n" ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_div_mpi( &X, &Y, &A, &N ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &U, 16, | 
|  | "256567336059E52CAE22925474705F39A94" ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &V, 16, | 
|  | "6613F26162223DF488E9CD48CC132C7A" \ | 
|  | "0AC93C701B001B092E4E5B9F73BCD27B" \ | 
|  | "9EE50D0657C77F374E903CDFA4C642" ) ); | 
|  |  | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "  MPI test #2 (div_mpi): " ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_mpi( &X, &U ) != 0 || | 
|  | mbedtls_mpi_cmp_mpi( &Y, &V ) != 0 ) | 
|  | { | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "failed\n" ); | 
|  |  | 
|  | ret = 1; | 
|  | goto cleanup; | 
|  | } | 
|  |  | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "passed\n" ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &X, &A, &E, &N, NULL ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &U, 16, | 
|  | "36E139AEA55215609D2816998ED020BB" \ | 
|  | "BD96C37890F65171D948E9BC7CBAA4D9" \ | 
|  | "325D24D6A3C12710F10A09FA08AB87" ) ); | 
|  |  | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "  MPI test #3 (exp_mod): " ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_mpi( &X, &U ) != 0 ) | 
|  | { | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "failed\n" ); | 
|  |  | 
|  | ret = 1; | 
|  | goto cleanup; | 
|  | } | 
|  |  | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "passed\n" ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &X, &A, &N ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &U, 16, | 
|  | "003A0AAEDD7E784FC07D8F9EC6E3BFD5" \ | 
|  | "C3DBA76456363A10869622EAC2DD84EC" \ | 
|  | "C5B8A74DAC4D09E03B5E0BE779F2DF61" ) ); | 
|  |  | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "  MPI test #4 (inv_mod): " ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_mpi( &X, &U ) != 0 ) | 
|  | { | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "failed\n" ); | 
|  |  | 
|  | ret = 1; | 
|  | goto cleanup; | 
|  | } | 
|  |  | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "passed\n" ); | 
|  |  | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "  MPI test #5 (simple gcd): " ); | 
|  |  | 
|  | for( i = 0; i < GCD_PAIR_COUNT; i++ ) | 
|  | { | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &X, gcd_pairs[i][0] ) ); | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &Y, gcd_pairs[i][1] ) ); | 
|  |  | 
|  | MBEDTLS_MPI_CHK( mbedtls_mpi_gcd( &A, &X, &Y ) ); | 
|  |  | 
|  | if( mbedtls_mpi_cmp_int( &A, gcd_pairs[i][2] ) != 0 ) | 
|  | { | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "failed at %d\n", i ); | 
|  |  | 
|  | ret = 1; | 
|  | goto cleanup; | 
|  | } | 
|  | } | 
|  |  | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "passed\n" ); | 
|  |  | 
|  | cleanup: | 
|  |  | 
|  | if( ret != 0 && verbose != 0 ) | 
|  | mbedtls_printf( "Unexpected error, return code = %08X\n", ret ); | 
|  |  | 
|  | mbedtls_mpi_free( &A ); mbedtls_mpi_free( &E ); mbedtls_mpi_free( &N ); mbedtls_mpi_free( &X ); | 
|  | mbedtls_mpi_free( &Y ); mbedtls_mpi_free( &U ); mbedtls_mpi_free( &V ); | 
|  |  | 
|  | if( verbose != 0 ) | 
|  | mbedtls_printf( "\n" ); | 
|  |  | 
|  | return( ret ); | 
|  | } | 
|  |  | 
|  | #endif /* MBEDTLS_SELF_TEST */ | 
|  |  | 
|  | #endif /* MBEDTLS_BIGNUM_C */ |