LXR linux/include/linux/mpi.h

   1/* mpi.h  -  Multi Precision Integers
   2 *      Copyright (C) 1994, 1996, 1998, 1999,
   3 *                    2000, 2001 Free Software Foundation, Inc.
   4 *
   5 * This file is part of GNUPG.
   6 *
   7 * GNUPG is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License as published by
   9 * the Free Software Foundation; either version 2 of the License, or
  10 * (at your option) any later version.
  11 *
  12 * GNUPG is distributed in the hope that it will be useful,
  13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 * GNU General Public License for more details.
  16 *
  17 * You should have received a copy of the GNU General Public License
  18 * along with this program; if not, write to the Free Software
  19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  20 *
  21 * Note: This code is heavily based on the GNU MP Library.
  22 *       Actually it's the same code with only minor changes in the
  23 *       way the data is stored; this is to support the abstraction
  24 *       of an optional secure memory allocation which may be used
  25 *       to avoid revealing of sensitive data due to paging etc.
  26 *       The GNU MP Library itself is published under the LGPL;
  27 *       however I decided to publish this code under the plain GPL.
  28 */
  29
  30#ifndef G10_MPI_H
  31#define G10_MPI_H
  32
  33#include <linux/types.h>
  34#include <linux/scatterlist.h>
  35
  36#define BYTES_PER_MPI_LIMB      (BITS_PER_LONG / 8)
  37#define BITS_PER_MPI_LIMB       BITS_PER_LONG
  38
  39typedef unsigned long int mpi_limb_t;
  40typedef signed long int mpi_limb_signed_t;
  41
  42struct gcry_mpi {
  43        int alloced;            /* array size (# of allocated limbs) */
  44        int nlimbs;             /* number of valid limbs */
  45        int nbits;              /* the real number of valid bits (info only) */
  46        int sign;               /* indicates a negative number */
  47        unsigned flags;         /* bit 0: array must be allocated in secure memory space */
  48        /* bit 1: not used */
  49        /* bit 2: the limb is a pointer to some m_alloced data */
  50        mpi_limb_t *d;          /* array with the limbs */
  51};
  52
  53typedef struct gcry_mpi *MPI;
  54
  55#define mpi_get_nlimbs(a)     ((a)->nlimbs)
  56#define mpi_is_neg(a)         ((a)->sign)
  57
  58/*-- mpiutil.c --*/
  59MPI mpi_alloc(unsigned nlimbs);
  60MPI mpi_alloc_secure(unsigned nlimbs);
  61MPI mpi_alloc_like(MPI a);
  62void mpi_free(MPI a);
  63int mpi_resize(MPI a, unsigned nlimbs);
  64int mpi_copy(MPI *copy, const MPI a);
  65void mpi_clear(MPI a);
  66int mpi_set(MPI w, MPI u);
  67int mpi_set_ui(MPI w, ulong u);
  68MPI mpi_alloc_set_ui(unsigned long u);
  69void mpi_m_check(MPI a);
  70void mpi_swap(MPI a, MPI b);
  71
  72/*-- mpicoder.c --*/
  73MPI do_encode_md(const void *sha_buffer, unsigned nbits);
  74MPI mpi_read_raw_data(const void *xbuffer, size_t nbytes);
  75MPI mpi_read_from_buffer(const void *buffer, unsigned *ret_nread);
  76MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int len);
  77int mpi_fromstr(MPI val, const char *str);
  78u32 mpi_get_keyid(MPI a, u32 *keyid);
  79void *mpi_get_buffer(MPI a, unsigned *nbytes, int *sign);
  80int mpi_read_buffer(MPI a, uint8_t *buf, unsigned buf_len, unsigned *nbytes,
  81                    int *sign);
  82void *mpi_get_secure_buffer(MPI a, unsigned *nbytes, int *sign);
  83int mpi_set_buffer(MPI a, const void *buffer, unsigned nbytes, int sign);
  84int mpi_write_to_sgl(MPI a, struct scatterlist *sg, unsigned *nbytes,
  85                     int *sign);
  86
  87#define log_mpidump g10_log_mpidump
  88
  89/*-- mpi-add.c --*/
  90int mpi_add_ui(MPI w, MPI u, ulong v);
  91int mpi_add(MPI w, MPI u, MPI v);
  92int mpi_addm(MPI w, MPI u, MPI v, MPI m);
  93int mpi_sub_ui(MPI w, MPI u, ulong v);
  94int mpi_sub(MPI w, MPI u, MPI v);
  95int mpi_subm(MPI w, MPI u, MPI v, MPI m);
  96
  97/*-- mpi-mul.c --*/
  98int mpi_mul_ui(MPI w, MPI u, ulong v);
  99int mpi_mul_2exp(MPI w, MPI u, ulong cnt);
 100int mpi_mul(MPI w, MPI u, MPI v);
 101int mpi_mulm(MPI w, MPI u, MPI v, MPI m);
 102
 103/*-- mpi-div.c --*/
 104ulong mpi_fdiv_r_ui(MPI rem, MPI dividend, ulong divisor);
 105int mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor);
 106int mpi_fdiv_q(MPI quot, MPI dividend, MPI divisor);
 107int mpi_fdiv_qr(MPI quot, MPI rem, MPI dividend, MPI divisor);
 108int mpi_tdiv_r(MPI rem, MPI num, MPI den);
 109int mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den);
 110int mpi_tdiv_q_2exp(MPI w, MPI u, unsigned count);
 111int mpi_divisible_ui(const MPI dividend, ulong divisor);
 112
 113/*-- mpi-gcd.c --*/
 114int mpi_gcd(MPI g, const MPI a, const MPI b);
 115
 116/*-- mpi-pow.c --*/
 117int mpi_pow(MPI w, MPI u, MPI v);
 118int mpi_powm(MPI res, MPI base, MPI exp, MPI mod);
 119
 120/*-- mpi-mpow.c --*/
 121int mpi_mulpowm(MPI res, MPI *basearray, MPI *exparray, MPI mod);
 122
 123/*-- mpi-cmp.c --*/
 124int mpi_cmp_ui(MPI u, ulong v);
 125int mpi_cmp(MPI u, MPI v);
 126
 127/*-- mpi-scan.c --*/
 128int mpi_getbyte(MPI a, unsigned idx);
 129void mpi_putbyte(MPI a, unsigned idx, int value);
 130unsigned mpi_trailing_zeros(MPI a);
 131
 132/*-- mpi-bit.c --*/
 133void mpi_normalize(MPI a);
 134unsigned mpi_get_nbits(MPI a);
 135int mpi_test_bit(MPI a, unsigned n);
 136int mpi_set_bit(MPI a, unsigned n);
 137int mpi_set_highbit(MPI a, unsigned n);
 138void mpi_clear_highbit(MPI a, unsigned n);
 139void mpi_clear_bit(MPI a, unsigned n);
 140int mpi_rshift(MPI x, MPI a, unsigned n);
 141
 142/*-- mpi-inv.c --*/
 143int mpi_invm(MPI x, MPI u, MPI v);
 144
 145/* inline functions */
 146
 147/**
 148 * mpi_get_size() - returns max size required to store the number
 149 *
 150 * @a:  A multi precision integer for which we want to allocate a bufer
 151 *
 152 * Return: size required to store the number
 153 */
 154static inline unsigned int mpi_get_size(MPI a)
 155{
 156        return a->nlimbs * BYTES_PER_MPI_LIMB;
 157}
 158#endif /*G10_MPI_H */
 159