lib/mpi/mpi-internal.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /* mpi-internal.h  -  Internal to the Multi Precision Integers
   3  *      Copyright (C) 1994, 1996 Free Software Foundation, Inc.
   4  *      Copyright (C) 1998, 2000 Free Software Foundation, Inc.
   5  *
   6  * This file is part of GnuPG.
   7  *
   8  * Note: This code is heavily based on the GNU MP Library.
   9  *       Actually it's the same code with only minor changes in the
  10  *       way the data is stored; this is to support the abstraction
  11  *       of an optional secure memory allocation which may be used
  12  *       to avoid revealing of sensitive data due to paging etc.
  13  *       The GNU MP Library itself is published under the LGPL;
  14  *       however I decided to publish this code under the plain GPL.
  15  */
  16
  17 #ifndef G10_MPI_INTERNAL_H
  18 #define G10_MPI_INTERNAL_H
  19
  20 #include <linux/module.h>
  21 #include <linux/kernel.h>
  22 #include <linux/slab.h>
  23 #include <linux/string.h>
  24 #include <linux/mpi.h>
  25 #include <linux/errno.h>
  26
  27 #define log_debug printk
  28 #define log_bug printk
  29
  30 #define assert(x) \
  31         do { \
  32                 if (!x) \
  33                         log_bug("failed assertion\n"); \
  34         } while (0);
  35
  36 /* If KARATSUBA_THRESHOLD is not already defined, define it to a
  37  * value which is good on most machines.  */
  38
  39 /* tested 4, 16, 32 and 64, where 16 gave the best performance when
  40  * checking a 768 and a 1024 bit ElGamal signature.
  41  * (wk 22.12.97) */
  42 #ifndef KARATSUBA_THRESHOLD
  43 #define KARATSUBA_THRESHOLD 16
  44 #endif
  45
  46 /* The code can't handle KARATSUBA_THRESHOLD smaller than 2.  */
  47 #if KARATSUBA_THRESHOLD < 2
  48 #undef KARATSUBA_THRESHOLD
  49 #define KARATSUBA_THRESHOLD 2
  50 #endif
  51
  52 typedef mpi_limb_t *mpi_ptr_t;  /* pointer to a limb */
  53 typedef int mpi_size_t;         /* (must be a signed type) */
  54
  55 /* Copy N limbs from S to D.  */
  56 #define MPN_COPY(d, s, n) \
  57         do {                                    \
  58                 mpi_size_t _i;                  \
  59                 for (_i = 0; _i < (n); _i++)    \
  60                         (d)[_i] = (s)[_i];      \
  61         } while (0)
  62
  63 #define MPN_COPY_DECR(d, s, n) \
  64         do {                                    \
  65                 mpi_size_t _i;                  \
  66                 for (_i = (n)-1; _i >= 0; _i--) \
  67                         (d)[_i] = (s)[_i];      \
  68         } while (0)
  69
  70 /* Zero N limbs at D */
  71 #define MPN_ZERO(d, n) \
  72         do {                                    \
  73                 int  _i;                        \
  74                 for (_i = 0; _i < (n); _i++)    \
  75                         (d)[_i] = 0;            \
  76         } while (0)
  77
  78 #define MPN_NORMALIZE(d, n)  \
  79         do {                                    \
  80                 while ((n) > 0) {               \
  81                         if ((d)[(n)-1])         \
  82                                 break;          \
  83                         (n)--;                  \
  84                 }                               \
  85         } while (0)
  86
  87 #define MPN_MUL_N_RECURSE(prodp, up, vp, size, tspace) \
  88         do {                                                    \
  89                 if ((size) < KARATSUBA_THRESHOLD)               \
  90                         mul_n_basecase(prodp, up, vp, size);    \
  91                 else                                            \
  92                         mul_n(prodp, up, vp, size, tspace);     \
  93         } while (0);
  94
  95 /*-- mpiutil.c --*/
  96 mpi_ptr_t mpi_alloc_limb_space(unsigned nlimbs);
  97 void mpi_free_limb_space(mpi_ptr_t a);
  98 void mpi_assign_limb_space(MPI a, mpi_ptr_t ap, unsigned nlimbs);
  99
 100 static inline mpi_limb_t mpihelp_add_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
 101                          mpi_size_t s1_size, mpi_limb_t s2_limb);
 102 mpi_limb_t mpihelp_add_n(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
 103                          mpi_ptr_t s2_ptr, mpi_size_t size);
 104 static inline mpi_limb_t mpihelp_add(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size,
 105                        mpi_ptr_t s2_ptr, mpi_size_t s2_size);
 106
 107 static inline mpi_limb_t mpihelp_sub_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
 108                          mpi_size_t s1_size, mpi_limb_t s2_limb);
 109 mpi_limb_t mpihelp_sub_n(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
 110                          mpi_ptr_t s2_ptr, mpi_size_t size);
 111 static inline mpi_limb_t mpihelp_sub(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size,
 112                        mpi_ptr_t s2_ptr, mpi_size_t s2_size);
 113
 114 /*-- mpih-cmp.c --*/
 115 int mpihelp_cmp(mpi_ptr_t op1_ptr, mpi_ptr_t op2_ptr, mpi_size_t size);
 116
 117 /*-- mpih-mul.c --*/
 118
 119 struct karatsuba_ctx {
 120         struct karatsuba_ctx *next;
 121         mpi_ptr_t tspace;
 122         mpi_size_t tspace_size;
 123         mpi_ptr_t tp;
 124         mpi_size_t tp_size;
 125 };
 126
 127 void mpihelp_release_karatsuba_ctx(struct karatsuba_ctx *ctx);
 128
 129 mpi_limb_t mpihelp_addmul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
 130                             mpi_size_t s1_size, mpi_limb_t s2_limb);
 131 mpi_limb_t mpihelp_submul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
 132                             mpi_size_t s1_size, mpi_limb_t s2_limb);
 133 int mpihelp_mul(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t usize,
 134                 mpi_ptr_t vp, mpi_size_t vsize, mpi_limb_t *_result);
 135 void mpih_sqr_n_basecase(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t size);
 136 void mpih_sqr_n(mpi_ptr_t prodp, mpi_ptr_t up, mpi_size_t size,
 137                 mpi_ptr_t tspace);
 138
 139 int mpihelp_mul_karatsuba_case(mpi_ptr_t prodp,
 140                                mpi_ptr_t up, mpi_size_t usize,
 141                                mpi_ptr_t vp, mpi_size_t vsize,
 142                                struct karatsuba_ctx *ctx);
 143
 144 /*-- generic_mpih-mul1.c --*/
 145 mpi_limb_t mpihelp_mul_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
 146                          mpi_size_t s1_size, mpi_limb_t s2_limb);
 147
 148 /*-- mpih-div.c --*/
 149 mpi_limb_t mpihelp_divrem(mpi_ptr_t qp, mpi_size_t qextra_limbs,
 150                           mpi_ptr_t np, mpi_size_t nsize,
 151                           mpi_ptr_t dp, mpi_size_t dsize);
 152
 153 /*-- generic_mpih-[lr]shift.c --*/
 154 mpi_limb_t mpihelp_lshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
 155                           unsigned cnt);
 156 mpi_limb_t mpihelp_rshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
 157                           unsigned cnt);
 158
 159 /* Define stuff for longlong.h.  */
 160 #define W_TYPE_SIZE BITS_PER_MPI_LIMB
 161 typedef mpi_limb_t UWtype;
 162 typedef unsigned int UHWtype;
 163 #if defined(__GNUC__)
 164 typedef unsigned int UQItype __attribute__ ((mode(QI)));
 165 typedef int SItype __attribute__ ((mode(SI)));
 166 typedef unsigned int USItype __attribute__ ((mode(SI)));
 167 typedef int DItype __attribute__ ((mode(DI)));
 168 typedef unsigned int UDItype __attribute__ ((mode(DI)));
 169 #else
 170 typedef unsigned char UQItype;
 171 typedef long SItype;
 172 typedef unsigned long USItype;
 173 #endif
 174
 175 #ifdef __GNUC__
 176 #include "mpi-inline.h"
 177 #endif
 178
 179 #endif /*G10_MPI_INTERNAL_H */