1 /* LibTomMath, multiple-precision integer library -- Tom St Denis
2  *
3  * LibTomMath is a library that provides multiple-precision
4  * integer arithmetic as well as number theoretic functionality.
5  *
6  * The library was designed directly after the MPI library by
7  * Michael Fromberger but has been written from scratch with
8  * additional optimizations in place.
9  *
10  * SPDX-License-Identifier: Unlicense
11  */
12 #ifndef TOMMATH_PRIV_H_
13 #define TOMMATH_PRIV_H_
14 
15 #include "tommath.h"
16 #include <ctype.h>
17 
18 #ifndef MIN
19 #define MIN(x, y) (((x) < (y)) ? (x) : (y))
20 #endif
21 
22 #ifndef MAX
23 #define MAX(x, y) (((x) > (y)) ? (x) : (y))
24 #endif
25 
26 #ifdef __cplusplus
27 extern "C" {
28 
29 /* C++ compilers don't like assigning void * to mp_digit * */
30 #define OPT_CAST(x) (x *)
31 
32 #else
33 
34 /* C on the other hand doesn't care */
35 #define OPT_CAST(x)
36 
37 #endif
38 
39 /* define heap macros */
40 #ifndef XMALLOC
41 /* default to libc stuff */
42 #   define XMALLOC   malloc
43 #   define XFREE     free
44 #   define XREALLOC  realloc
45 #   define XCALLOC   calloc
46 #else
47 /* prototypes for our heap functions */
48 extern void *XMALLOC(size_t n);
49 extern void *XREALLOC(void *p, size_t n);
50 extern void *XCALLOC(size_t n, size_t s);
51 extern void XFREE(void *p);
52 #endif
53 
54 /* lowlevel functions, do not call! */
55 int s_mp_add(const mp_int *a, const mp_int *b, mp_int *c);
56 int s_mp_sub(const mp_int *a, const mp_int *b, mp_int *c);
57 #define s_mp_mul(a, b, c) s_mp_mul_digs(a, b, c, (a)->used + (b)->used + 1)
58 int fast_s_mp_mul_digs(const mp_int *a, const mp_int *b, mp_int *c, int digs);
59 int s_mp_mul_digs(const mp_int *a, const mp_int *b, mp_int *c, int digs);
60 int fast_s_mp_mul_high_digs(const mp_int *a, const mp_int *b, mp_int *c, int digs);
61 int s_mp_mul_high_digs(const mp_int *a, const mp_int *b, mp_int *c, int digs);
62 int fast_s_mp_sqr(const mp_int *a, mp_int *b);
63 int s_mp_sqr(const mp_int *a, mp_int *b);
64 int mp_karatsuba_mul(const mp_int *a, const mp_int *b, mp_int *c);
65 int mp_toom_mul(const mp_int *a, const mp_int *b, mp_int *c);
66 int mp_karatsuba_sqr(const mp_int *a, mp_int *b);
67 int mp_toom_sqr(const mp_int *a, mp_int *b);
68 int fast_mp_invmod(const mp_int *a, const mp_int *b, mp_int *c);
69 int mp_invmod_slow(const mp_int *a, const mp_int *b, mp_int *c);
70 int fast_mp_montgomery_reduce(mp_int *x, const mp_int *n, mp_digit rho);
71 int mp_exptmod_fast(const mp_int *G, const mp_int *X, const mp_int *P, mp_int *Y, int redmode);
72 int s_mp_exptmod(const mp_int *G, const mp_int *X, const mp_int *P, mp_int *Y, int redmode);
73 void bn_reverse(unsigned char *s, int len);
74 
75 extern const char *const mp_s_rmap;
76 extern const unsigned char mp_s_rmap_reverse[];
77 extern const size_t mp_s_rmap_reverse_sz;
78 
79 /* Fancy macro to set an MPI from another type.
80  * There are several things assumed:
81  *  x is the counter and unsigned
82  *  a is the pointer to the MPI
83  *  b is the original value that should be set in the MPI.
84  */
85 #define MP_SET_XLONG(func_name, type)                    \
86 int func_name (mp_int * a, type b)                       \
87 {                                                        \
88   unsigned int  x;                                       \
89   int           res;                                     \
90                                                          \
91   mp_zero (a);                                           \
92                                                          \
93   /* set four bits at a time */                          \
94   for (x = 0; x < (sizeof(type) * 2u); x++) {            \
95     /* shift the number up four bits */                  \
96     if ((res = mp_mul_2d (a, 4, a)) != MP_OKAY) {        \
97       return res;                                        \
98     }                                                    \
99                                                          \
100     /* OR in the top four bits of the source */          \
101     a->dp[0] |= (mp_digit)(b >> ((sizeof(type) * 8u) - 4u)) & 15uL;\
102                                                          \
103     /* shift the source up to the next four bits */      \
104     b <<= 4;                                             \
105                                                          \
106     /* ensure that digits are not clamped off */         \
107     a->used += 1;                                        \
108   }                                                      \
109   mp_clamp (a);                                          \
110   return MP_OKAY;                                        \
111 }
112 
113 #ifdef __cplusplus
114 }
115 #endif
116 
117 #endif
118 
119 
120 /* ref:         $Format:%D$ */
121 /* git commit:  $Format:%H$ */
122 /* commit time: $Format:%ai$ */
123