bignum.h

Go to the documentation of this file.

/*
 *  Copyright The Mbed TLS Contributors
 *  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.
 */
#ifndef MBEDTLS_BIGNUM_H
#define MBEDTLS_BIGNUM_H
#include "mbedtls/private_access.h"

#include "mbedtls/build_info.h"

#include <stddef.h>
#include <stdint.h>

#if defined(MBEDTLS_FS_IO)
#include <stdio.h>
#endif

#define MBEDTLS_ERR_MPI_FILE_IO_ERROR                     -0x0002

#define MBEDTLS_ERR_MPI_BAD_INPUT_DATA                    -0x0004

#define MBEDTLS_ERR_MPI_INVALID_CHARACTER                 -0x0006

#define MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL                  -0x0008

#define MBEDTLS_ERR_MPI_NEGATIVE_VALUE                    -0x000A

#define MBEDTLS_ERR_MPI_DIVISION_BY_ZERO                  -0x000C

#define MBEDTLS_ERR_MPI_NOT_ACCEPTABLE                    -0x000E

#define MBEDTLS_ERR_MPI_ALLOC_FAILED                      -0x0010

#define MBEDTLS_MPI_CHK(f)       \
    do                           \
    {                            \
        if( ( ret = (f) ) != 0 ) \
            goto cleanup;        \
    } while( 0 )

/*
 * Maximum size MPIs are allowed to grow to in number of limbs.
 */
#define MBEDTLS_MPI_MAX_LIMBS                             10000

#if !defined(MBEDTLS_MPI_WINDOW_SIZE)
/*
 * Maximum window size used for modular exponentiation. Default: 6
 * Minimum value: 1. Maximum value: 6.
 *
 * Result is an array of ( 2 ** MBEDTLS_MPI_WINDOW_SIZE ) MPIs used
 * for the sliding window calculation. (So 64 by default)
 *
 * Reduction in size, reduces speed.
 */
#define MBEDTLS_MPI_WINDOW_SIZE                           6        
#endif /* !MBEDTLS_MPI_WINDOW_SIZE */

#if !defined(MBEDTLS_MPI_MAX_SIZE)
/*
 * Maximum size of MPIs allowed in bits and bytes for user-MPIs.
 * ( Default: 512 bytes => 4096 bits, Maximum tested: 2048 bytes => 16384 bits )
 *
 * Note: Calculations can temporarily result in larger MPIs. So the number
 * of limbs required (MBEDTLS_MPI_MAX_LIMBS) is higher.
 */
#define MBEDTLS_MPI_MAX_SIZE                              1024     
#endif /* !MBEDTLS_MPI_MAX_SIZE */

#define MBEDTLS_MPI_MAX_BITS                              ( 8 * MBEDTLS_MPI_MAX_SIZE )    
/*
 * When reading from files with mbedtls_mpi_read_file() and writing to files with
 * mbedtls_mpi_write_file() the buffer should have space
 * for a (short) label, the MPI (in the provided radix), the newline
 * characters and the '\0'.
 *
 * By default we assume at least a 10 char label, a minimum radix of 10
 * (decimal) and a maximum of 4096 bit numbers (1234 decimal chars).
 * Autosized at compile time for at least a 10 char label, a minimum radix
 * of 10 (decimal) for a number of MBEDTLS_MPI_MAX_BITS size.
 *
 * This used to be statically sized to 1250 for a maximum of 4096 bit
 * numbers (1234 decimal chars).
 *
 * Calculate using the formula:
 *  MBEDTLS_MPI_RW_BUFFER_SIZE = ceil(MBEDTLS_MPI_MAX_BITS / ln(10) * ln(2)) +
 *                                LabelSize + 6
 */
#define MBEDTLS_MPI_MAX_BITS_SCALE100          ( 100 * MBEDTLS_MPI_MAX_BITS )
#define MBEDTLS_LN_2_DIV_LN_10_SCALE100                 332
#define MBEDTLS_MPI_RW_BUFFER_SIZE             ( ((MBEDTLS_MPI_MAX_BITS_SCALE100 + MBEDTLS_LN_2_DIV_LN_10_SCALE100 - 1) / MBEDTLS_LN_2_DIV_LN_10_SCALE100) + 10 + 6 )

/*
 * Define the base integer type, architecture-wise.
 *
 * 32 or 64-bit integer types can be forced regardless of the underlying
 * architecture by defining MBEDTLS_HAVE_INT32 or MBEDTLS_HAVE_INT64
 * respectively and undefining MBEDTLS_HAVE_ASM.
 *
 * Double-width integers (e.g. 128-bit in 64-bit architectures) can be
 * disabled by defining MBEDTLS_NO_UDBL_DIVISION.
 */
#if !defined(MBEDTLS_HAVE_INT32)
    #if defined(_MSC_VER) && defined(_M_AMD64)
        /* Always choose 64-bit when using MSC */
        #if !defined(MBEDTLS_HAVE_INT64)
            #define MBEDTLS_HAVE_INT64
        #endif /* !MBEDTLS_HAVE_INT64 */
        typedef  int64_t mbedtls_mpi_sint;
        typedef uint64_t mbedtls_mpi_uint;
    #elif defined(__GNUC__) && (                         \
        defined(__amd64__) || defined(__x86_64__)     || \
        defined(__ppc64__) || defined(__powerpc64__)  || \
        defined(__ia64__)  || defined(__alpha__)      || \
        ( defined(__sparc__) && defined(__arch64__) ) || \
        defined(__s390x__) || defined(__mips64)       || \
        defined(__aarch64__) )
        #if !defined(MBEDTLS_HAVE_INT64)
            #define MBEDTLS_HAVE_INT64
        #endif /* MBEDTLS_HAVE_INT64 */
        typedef  int64_t mbedtls_mpi_sint;
        typedef uint64_t mbedtls_mpi_uint;
        #if !defined(MBEDTLS_NO_UDBL_DIVISION)
            /* mbedtls_t_udbl defined as 128-bit unsigned int */
            typedef unsigned int mbedtls_t_udbl __attribute__((mode(TI)));
            #define MBEDTLS_HAVE_UDBL
        #endif /* !MBEDTLS_NO_UDBL_DIVISION */
    #elif defined(__ARMCC_VERSION) && defined(__aarch64__)
        /*
         * __ARMCC_VERSION is defined for both armcc and armclang and
         * __aarch64__ is only defined by armclang when compiling 64-bit code
         */
        #if !defined(MBEDTLS_HAVE_INT64)
            #define MBEDTLS_HAVE_INT64
        #endif /* !MBEDTLS_HAVE_INT64 */
        typedef  int64_t mbedtls_mpi_sint;
        typedef uint64_t mbedtls_mpi_uint;
        #if !defined(MBEDTLS_NO_UDBL_DIVISION)
            /* mbedtls_t_udbl defined as 128-bit unsigned int */
            typedef __uint128_t mbedtls_t_udbl;
            #define MBEDTLS_HAVE_UDBL
        #endif /* !MBEDTLS_NO_UDBL_DIVISION */
    #elif defined(MBEDTLS_HAVE_INT64)
        /* Force 64-bit integers with unknown compiler */
        typedef  int64_t mbedtls_mpi_sint;
        typedef uint64_t mbedtls_mpi_uint;
    #endif
#endif /* !MBEDTLS_HAVE_INT32 */

#if !defined(MBEDTLS_HAVE_INT64)
    /* Default to 32-bit compilation */
    #if !defined(MBEDTLS_HAVE_INT32)
        #define MBEDTLS_HAVE_INT32
    #endif /* !MBEDTLS_HAVE_INT32 */
    typedef  int32_t mbedtls_mpi_sint;
    typedef uint32_t mbedtls_mpi_uint;
    #if !defined(MBEDTLS_NO_UDBL_DIVISION)
        typedef uint64_t mbedtls_t_udbl;
        #define MBEDTLS_HAVE_UDBL
    #endif /* !MBEDTLS_NO_UDBL_DIVISION */
#endif /* !MBEDTLS_HAVE_INT64 */

#ifdef __cplusplus
extern "C" {
#endif

typedef struct mbedtls_mpi
{
    int MBEDTLS_PRIVATE(s);              
    size_t MBEDTLS_PRIVATE(n);           
    mbedtls_mpi_uint *MBEDTLS_PRIVATE(p);          
}
mbedtls_mpi;

void mbedtls_mpi_init( mbedtls_mpi *X );

void mbedtls_mpi_free( mbedtls_mpi *X );

int mbedtls_mpi_grow( mbedtls_mpi *X, size_t nblimbs );

int mbedtls_mpi_shrink( mbedtls_mpi *X, size_t nblimbs );

int mbedtls_mpi_copy( mbedtls_mpi *X, const mbedtls_mpi *Y );

void mbedtls_mpi_swap( mbedtls_mpi *X, mbedtls_mpi *Y );

int mbedtls_mpi_safe_cond_assign( mbedtls_mpi *X, const mbedtls_mpi *Y, unsigned char assign );

int mbedtls_mpi_safe_cond_swap( mbedtls_mpi *X, mbedtls_mpi *Y, unsigned char assign );

int mbedtls_mpi_lset( mbedtls_mpi *X, mbedtls_mpi_sint z );

int mbedtls_mpi_get_bit( const mbedtls_mpi *X, size_t pos );

int mbedtls_mpi_set_bit( mbedtls_mpi *X, size_t pos, unsigned char val );

size_t mbedtls_mpi_lsb( const mbedtls_mpi *X );

size_t mbedtls_mpi_bitlen( const mbedtls_mpi *X );

size_t mbedtls_mpi_size( const mbedtls_mpi *X );

int mbedtls_mpi_read_string( mbedtls_mpi *X, int radix, const char *s );

int mbedtls_mpi_write_string( const mbedtls_mpi *X, int radix,
                              char *buf, size_t buflen, size_t *olen );

#if defined(MBEDTLS_FS_IO)

int mbedtls_mpi_read_file( mbedtls_mpi *X, int radix, FILE *fin );

int mbedtls_mpi_write_file( const char *p, const mbedtls_mpi *X,
                            int radix, FILE *fout );
#endif /* MBEDTLS_FS_IO */

int mbedtls_mpi_read_binary( mbedtls_mpi *X, const unsigned char *buf,
                             size_t buflen );

int mbedtls_mpi_read_binary_le( mbedtls_mpi *X,
                                const unsigned char *buf, size_t buflen );

int mbedtls_mpi_write_binary( const mbedtls_mpi *X, unsigned char *buf,
                              size_t buflen );

int mbedtls_mpi_write_binary_le( const mbedtls_mpi *X,
                                 unsigned char *buf, size_t buflen );

int mbedtls_mpi_shift_l( mbedtls_mpi *X, size_t count );

int mbedtls_mpi_shift_r( mbedtls_mpi *X, size_t count );

int mbedtls_mpi_cmp_abs( const mbedtls_mpi *X, const mbedtls_mpi *Y );

int mbedtls_mpi_cmp_mpi( const mbedtls_mpi *X, const mbedtls_mpi *Y );

int mbedtls_mpi_lt_mpi_ct( const mbedtls_mpi *X, const mbedtls_mpi *Y,
        unsigned *ret );

int mbedtls_mpi_cmp_int( const mbedtls_mpi *X, mbedtls_mpi_sint z );

int mbedtls_mpi_add_abs( mbedtls_mpi *X, const mbedtls_mpi *A,
                         const mbedtls_mpi *B );

int mbedtls_mpi_sub_abs( mbedtls_mpi *X, const mbedtls_mpi *A,
                         const mbedtls_mpi *B );

int mbedtls_mpi_add_mpi( mbedtls_mpi *X, const mbedtls_mpi *A,
                         const mbedtls_mpi *B );

int mbedtls_mpi_sub_mpi( mbedtls_mpi *X, const mbedtls_mpi *A,
                         const mbedtls_mpi *B );

int mbedtls_mpi_add_int( mbedtls_mpi *X, const mbedtls_mpi *A,
                         mbedtls_mpi_sint b );

int mbedtls_mpi_sub_int( mbedtls_mpi *X, const mbedtls_mpi *A,
                         mbedtls_mpi_sint b );

int mbedtls_mpi_mul_mpi( mbedtls_mpi *X, const mbedtls_mpi *A,
                         const mbedtls_mpi *B );

int mbedtls_mpi_mul_int( mbedtls_mpi *X, const mbedtls_mpi *A,
                         mbedtls_mpi_uint b );

int mbedtls_mpi_div_mpi( mbedtls_mpi *Q, mbedtls_mpi *R, const mbedtls_mpi *A,
                         const mbedtls_mpi *B );

int mbedtls_mpi_div_int( mbedtls_mpi *Q, mbedtls_mpi *R, const mbedtls_mpi *A,
                         mbedtls_mpi_sint b );

int mbedtls_mpi_mod_mpi( mbedtls_mpi *R, const mbedtls_mpi *A,
                         const mbedtls_mpi *B );

int mbedtls_mpi_mod_int( mbedtls_mpi_uint *r, const mbedtls_mpi *A,
                         mbedtls_mpi_sint b );

int mbedtls_mpi_exp_mod( mbedtls_mpi *X, const mbedtls_mpi *A,
                         const mbedtls_mpi *E, const mbedtls_mpi *N,
                         mbedtls_mpi *prec_RR );

int mbedtls_mpi_fill_random( mbedtls_mpi *X, size_t size,
                     int (*f_rng)(void *, unsigned char *, size_t),
                     void *p_rng );

int mbedtls_mpi_random( mbedtls_mpi *X,
                        mbedtls_mpi_sint min,
                        const mbedtls_mpi *N,
                        int (*f_rng)(void *, unsigned char *, size_t),
                        void *p_rng );

int mbedtls_mpi_gcd( mbedtls_mpi *G, const mbedtls_mpi *A,
                     const mbedtls_mpi *B );

int mbedtls_mpi_inv_mod( mbedtls_mpi *X, const mbedtls_mpi *A,
                         const mbedtls_mpi *N );

int mbedtls_mpi_is_prime_ext( const mbedtls_mpi *X, int rounds,
                              int (*f_rng)(void *, unsigned char *, size_t),
                              void *p_rng );
typedef enum {
    MBEDTLS_MPI_GEN_PRIME_FLAG_DH =      0x0001, 
    MBEDTLS_MPI_GEN_PRIME_FLAG_LOW_ERR = 0x0002, 
} mbedtls_mpi_gen_prime_flag_t;

int mbedtls_mpi_gen_prime( mbedtls_mpi *X, size_t nbits, int flags,
                   int (*f_rng)(void *, unsigned char *, size_t),
                   void *p_rng );

#if defined(MBEDTLS_SELF_TEST)

int mbedtls_mpi_self_test( int verbose );

#endif /* MBEDTLS_SELF_TEST */

#ifdef __cplusplus
}
#endif

#endif /* bignum.h */