diff options
Diffstat (limited to 'libtommath/tommath_private.h')
| -rw-r--r-- | libtommath/tommath_private.h | 382 |
1 files changed, 281 insertions, 101 deletions
diff --git a/libtommath/tommath_private.h b/libtommath/tommath_private.h index aeda684..1a0096f 100644 --- a/libtommath/tommath_private.h +++ b/libtommath/tommath_private.h @@ -1,123 +1,303 @@ -/* LibTomMath, multiple-precision integer library -- Tom St Denis - * - * LibTomMath is a library that provides multiple-precision - * integer arithmetic as well as number theoretic functionality. - * - * The library was designed directly after the MPI library by - * Michael Fromberger but has been written from scratch with - * additional optimizations in place. - * - * The library is free for all purposes without any express - * guarantee it works. - * - * Tom St Denis, tstdenis82@gmail.com, http://math.libtomcrypt.com - */ +/* LibTomMath, multiple-precision integer library -- Tom St Denis */ +/* SPDX-License-Identifier: Unlicense */ + #ifndef TOMMATH_PRIV_H_ #define TOMMATH_PRIV_H_ -#include <tommath.h> -#include <ctype.h> +#include "tommath.h" +#include "tommath_class.h" -#ifndef MIN - #define MIN(x,y) (((x) < (y)) ? (x) : (y)) +/* + * Private symbols + * --------------- + * + * On Unix symbols can be marked as hidden if libtommath is compiled + * as a shared object. By default, symbols are visible. + * As of now, this feature is opt-in via the MP_PRIVATE_SYMBOLS define. + * + * On Win32 a .def file must be used to specify the exported symbols. + */ +#if defined (MP_PRIVATE_SYMBOLS) && defined(__GNUC__) && __GNUC__ >= 4 +# define MP_PRIVATE __attribute__ ((visibility ("hidden"))) +#else +# define MP_PRIVATE #endif -#ifndef MAX - #define MAX(x,y) (((x) > (y)) ? (x) : (y)) +/* Hardening libtommath + * -------------------- + * + * By default memory is zeroed before calling + * MP_FREE to avoid leaking data. This is good + * practice in cryptographical applications. + * + * Note however that memory allocators used + * in cryptographical applications can often + * be configured by itself to clear memory, + * rendering the clearing in tommath unnecessary. + * See for example https://github.com/GrapheneOS/hardened_malloc + * and the option CONFIG_ZERO_ON_FREE. + * + * Furthermore there are applications which + * value performance more and want this + * feature to be disabled. For such applications + * define MP_NO_ZERO_ON_FREE during compilation. + */ +#ifdef MP_NO_ZERO_ON_FREE +# define MP_FREE_BUFFER(mem, size) MP_FREE((mem), (size)) +# define MP_FREE_DIGITS(mem, digits) MP_FREE((mem), sizeof (mp_digit) * (size_t)(digits)) +#else +# define MP_FREE_BUFFER(mem, size) \ +do { \ + size_t fs_ = (size); \ + void* fm_ = (mem); \ + if (fm_ != NULL) { \ + MP_ZERO_BUFFER(fm_, fs_); \ + MP_FREE(fm_, fs_); \ + } \ +} while (0) +# define MP_FREE_DIGITS(mem, digits) \ +do { \ + int fd_ = (digits); \ + void* fm_ = (mem); \ + if (fm_ != NULL) { \ + size_t fs_ = sizeof (mp_digit) * (size_t)fd_; \ + MP_ZERO_BUFFER(fm_, fs_); \ + MP_FREE(fm_, fs_); \ + } \ +} while (0) #endif -#ifdef __cplusplus -extern "C" { - -/* C++ compilers don't like assigning void * to mp_digit * */ -#define OPT_CAST(x) (x *) - +#ifdef MP_USE_MEMSET +# include <string.h> +# define MP_ZERO_BUFFER(mem, size) memset((mem), 0, (size)) +# define MP_ZERO_DIGITS(mem, digits) \ +do { \ + int zd_ = (digits); \ + if (zd_ > 0) { \ + memset((mem), 0, sizeof(mp_digit) * (size_t)zd_); \ + } \ +} while (0) #else +# define MP_ZERO_BUFFER(mem, size) \ +do { \ + size_t zs_ = (size); \ + char* zm_ = (char*)(mem); \ + while (zs_-- > 0u) { \ + *zm_++ = '\0'; \ + } \ +} while (0) +# define MP_ZERO_DIGITS(mem, digits) \ +do { \ + int zd_ = (digits); \ + mp_digit* zm_ = (mem); \ + while (zd_-- > 0) { \ + *zm_++ = 0; \ + } \ +} while (0) +#endif -/* C on the other hand doesn't care */ -#define OPT_CAST(x) +/* Tunable cutoffs + * --------------- + * + * - In the default settings, a cutoff X can be modified at runtime + * by adjusting the corresponding X_CUTOFF variable. + * + * - Tunability of the library can be disabled at compile time + * by defining the MP_FIXED_CUTOFFS macro. + * + * - There is an additional file tommath_cutoffs.h, which defines + * the default cutoffs. These can be adjusted manually or by the + * autotuner. + * + */ +#ifdef MP_FIXED_CUTOFFS +# include "tommath_cutoffs.h" +# define MP_KARATSUBA_MUL_CUTOFF MP_DEFAULT_KARATSUBA_MUL_CUTOFF +# define MP_KARATSUBA_SQR_CUTOFF MP_DEFAULT_KARATSUBA_SQR_CUTOFF +# define MP_TOOM_MUL_CUTOFF MP_DEFAULT_TOOM_MUL_CUTOFF +# define MP_TOOM_SQR_CUTOFF MP_DEFAULT_TOOM_SQR_CUTOFF +#else +# define MP_KARATSUBA_MUL_CUTOFF KARATSUBA_MUL_CUTOFF +# define MP_KARATSUBA_SQR_CUTOFF KARATSUBA_SQR_CUTOFF +# define MP_TOOM_MUL_CUTOFF TOOM_MUL_CUTOFF +# define MP_TOOM_SQR_CUTOFF TOOM_SQR_CUTOFF #endif /* define heap macros */ -#ifndef XMALLOC - /* default to libc stuff */ - #define XMALLOC malloc - #define XFREE free - #define XREALLOC realloc - #define XCALLOC calloc +#ifndef MP_MALLOC +/* default to libc stuff */ +# include <stdlib.h> +# define MP_MALLOC(size) malloc(size) +# define MP_REALLOC(mem, oldsize, newsize) realloc((mem), (newsize)) +# define MP_CALLOC(nmemb, size) calloc((nmemb), (size)) +# define MP_FREE(mem, size) free(mem) #else - /* prototypes for our heap functions */ - extern void *XMALLOC(size_t n); - extern void *XREALLOC(void *p, size_t n); - extern void *XCALLOC(size_t n, size_t s); - extern void XFREE(void *p); +/* prototypes for our heap functions */ +extern void *MP_MALLOC(size_t size); +extern void *MP_REALLOC(void *mem, size_t oldsize, size_t newsize); +extern void *MP_CALLOC(size_t nmemb, size_t size); +extern void MP_FREE(void *mem, size_t size); #endif -/* lowlevel functions, do not call! */ -int s_mp_add(mp_int *a, mp_int *b, mp_int *c); -int s_mp_sub(mp_int *a, mp_int *b, mp_int *c); -#define s_mp_mul(a, b, c) s_mp_mul_digs(a, b, c, (a)->used + (b)->used + 1) -int fast_s_mp_mul_digs(mp_int *a, mp_int *b, mp_int *c, int digs); -int s_mp_mul_digs(mp_int *a, mp_int *b, mp_int *c, int digs); -int fast_s_mp_mul_high_digs(mp_int *a, mp_int *b, mp_int *c, int digs); -int s_mp_mul_high_digs(mp_int *a, mp_int *b, mp_int *c, int digs); -int fast_s_mp_sqr(mp_int *a, mp_int *b); -int s_mp_sqr(mp_int *a, mp_int *b); -int mp_karatsuba_mul(mp_int *a, mp_int *b, mp_int *c); -int mp_toom_mul(mp_int *a, mp_int *b, mp_int *c); -int mp_karatsuba_sqr(mp_int *a, mp_int *b); -int mp_toom_sqr(mp_int *a, mp_int *b); -int fast_mp_invmod(mp_int *a, mp_int *b, mp_int *c); -int mp_invmod_slow (mp_int * a, mp_int * b, mp_int * c); -int fast_mp_montgomery_reduce(mp_int *x, mp_int *n, mp_digit rho); -int mp_exptmod_fast(mp_int *G, mp_int *X, mp_int *P, mp_int *Y, int redmode); -int s_mp_exptmod (mp_int * G, mp_int * X, mp_int * P, mp_int * Y, int redmode); -void bn_reverse(unsigned char *s, int len); - -extern const char *mp_s_rmap; - -/* Fancy macro to set an MPI from another type. - * There are several things assumed: - * x is the counter and unsigned - * a is the pointer to the MPI - * b is the original value that should be set in the MPI. - */ -#define MP_SET_XLONG(func_name, type) \ -int func_name (mp_int * a, type b) \ -{ \ - unsigned int x; \ - int res; \ - \ - mp_zero (a); \ - \ - /* set four bits at a time */ \ - for (x = 0; x < (sizeof(type) * 2u); x++) { \ - /* shift the number up four bits */ \ - if ((res = mp_mul_2d (a, 4, a)) != MP_OKAY) { \ - return res; \ - } \ - \ - /* OR in the top four bits of the source */ \ - a->dp[0] |= (b >> ((sizeof(type) * 8u) - 4u)) & 15u; \ - \ - /* shift the source up to the next four bits */ \ - b <<= 4; \ - \ - /* ensure that digits are not clamped off */ \ - a->used += 1; \ - } \ - mp_clamp (a); \ - return MP_OKAY; \ -} - -#ifdef __cplusplus - } +/* feature detection macro */ +#ifdef _MSC_VER +/* Prevent false positive: not enough arguments for function-like macro invocation */ +#pragma warning(disable: 4003) #endif +#define MP_STRINGIZE(x) MP__STRINGIZE(x) +#define MP__STRINGIZE(x) ""#x"" +#define MP_HAS(x) (sizeof(MP_STRINGIZE(BN_##x##_C)) == 1u) + +/* TODO: Remove private_mp_word as soon as deprecated mp_word is removed from tommath. */ +#undef mp_word +typedef private_mp_word mp_word; + +#define MP_MIN(x, y) (((x) < (y)) ? (x) : (y)) +#define MP_MAX(x, y) (((x) > (y)) ? (x) : (y)) + +/* Static assertion */ +#define MP_STATIC_ASSERT(msg, cond) typedef char mp_static_assert_##msg[(cond) ? 1 : -1]; +/* ---> Basic Manipulations <--- */ +#define MP_IS_ZERO(a) ((a)->used == 0) +#define MP_IS_EVEN(a) (((a)->used == 0) || (((a)->dp[0] & 1u) == 0u)) +#define MP_IS_ODD(a) (((a)->used > 0) && (((a)->dp[0] & 1u) == 1u)) + +#define MP_SIZEOF_BITS(type) ((size_t)CHAR_BIT * sizeof(type)) +#define MP_MAXFAST (int)(1uL << (MP_SIZEOF_BITS(mp_word) - (2u * (size_t)MP_DIGIT_BIT))) + +/* TODO: Remove PRIVATE_MP_WARRAY as soon as deprecated MP_WARRAY is removed from tommath.h */ +#undef MP_WARRAY +#define MP_WARRAY PRIVATE_MP_WARRAY + +/* TODO: Remove PRIVATE_MP_PREC as soon as deprecated MP_PREC is removed from tommath.h */ +#ifdef PRIVATE_MP_PREC +# undef MP_PREC +# define MP_PREC PRIVATE_MP_PREC #endif +/* Minimum number of available digits in mp_int, MP_PREC >= MP_MIN_PREC */ +#define MP_MIN_PREC ((((int)MP_SIZEOF_BITS(long long) + MP_DIGIT_BIT) - 1) / MP_DIGIT_BIT) -/* ref: $Format:%D$ */ -/* git commit: $Format:%H$ */ -/* commit time: $Format:%ai$ */ +MP_STATIC_ASSERT(prec_geq_min_prec, MP_PREC >= MP_MIN_PREC) + +/* random number source */ +extern MP_PRIVATE mp_err(*s_mp_rand_source)(void *out, size_t size); + +/* lowlevel functions, do not call! */ +MP_PRIVATE mp_bool s_mp_get_bit(const mp_int *a, unsigned int b); +MP_PRIVATE mp_err s_mp_add(const mp_int *a, const mp_int *b, mp_int *c) MP_WUR; +MP_PRIVATE mp_err s_mp_sub(const mp_int *a, const mp_int *b, mp_int *c) MP_WUR; +MP_PRIVATE mp_err s_mp_mul_digs_fast(const mp_int *a, const mp_int *b, mp_int *c, int digs) MP_WUR; +MP_PRIVATE mp_err s_mp_mul_digs(const mp_int *a, const mp_int *b, mp_int *c, int digs) MP_WUR; +MP_PRIVATE mp_err s_mp_mul_high_digs_fast(const mp_int *a, const mp_int *b, mp_int *c, int digs) MP_WUR; +MP_PRIVATE mp_err s_mp_mul_high_digs(const mp_int *a, const mp_int *b, mp_int *c, int digs) MP_WUR; +MP_PRIVATE mp_err s_mp_sqr_fast(const mp_int *a, mp_int *b) MP_WUR; +MP_PRIVATE mp_err s_mp_sqr(const mp_int *a, mp_int *b) MP_WUR; +MP_PRIVATE mp_err s_mp_balance_mul(const mp_int *a, const mp_int *b, mp_int *c) MP_WUR; +MP_PRIVATE mp_err s_mp_karatsuba_mul(const mp_int *a, const mp_int *b, mp_int *c) MP_WUR; +MP_PRIVATE mp_err s_mp_toom_mul(const mp_int *a, const mp_int *b, mp_int *c) MP_WUR; +MP_PRIVATE mp_err s_mp_karatsuba_sqr(const mp_int *a, mp_int *b) MP_WUR; +MP_PRIVATE mp_err s_mp_toom_sqr(const mp_int *a, mp_int *b) MP_WUR; +MP_PRIVATE mp_err s_mp_invmod_fast(const mp_int *a, const mp_int *b, mp_int *c) MP_WUR; +MP_PRIVATE mp_err s_mp_invmod_slow(const mp_int *a, const mp_int *b, mp_int *c) MP_WUR; +MP_PRIVATE mp_err s_mp_montgomery_reduce_fast(mp_int *x, const mp_int *n, mp_digit rho) MP_WUR; +MP_PRIVATE mp_err s_mp_exptmod_fast(const mp_int *G, const mp_int *X, const mp_int *P, mp_int *Y, int redmode) MP_WUR; +MP_PRIVATE mp_err s_mp_exptmod(const mp_int *G, const mp_int *X, const mp_int *P, mp_int *Y, int redmode) MP_WUR; +MP_PRIVATE mp_err s_mp_rand_platform(void *p, size_t n) MP_WUR; +MP_PRIVATE mp_err s_mp_prime_random_ex(mp_int *a, int t, int size, int flags, private_mp_prime_callback cb, void *dat); +MP_PRIVATE void s_mp_reverse(unsigned char *s, size_t len); +MP_PRIVATE mp_err s_mp_prime_is_divisible(const mp_int *a, mp_bool *result); + +/* TODO: jenkins prng is not thread safe as of now */ +MP_PRIVATE mp_err s_mp_rand_jenkins(void *p, size_t n) MP_WUR; +MP_PRIVATE void s_mp_rand_jenkins_init(uint64_t seed); + +extern MP_PRIVATE const char *const mp_s_rmap; +extern MP_PRIVATE const uint8_t mp_s_rmap_reverse[]; +extern MP_PRIVATE const size_t mp_s_rmap_reverse_sz; +extern MP_PRIVATE const mp_digit *s_mp_prime_tab; + +/* deprecated functions */ +MP_DEPRECATED(s_mp_invmod_fast) mp_err fast_mp_invmod(const mp_int *a, const mp_int *b, mp_int *c); +MP_DEPRECATED(s_mp_montgomery_reduce_fast) mp_err fast_mp_montgomery_reduce(mp_int *x, const mp_int *n, + mp_digit rho); +MP_DEPRECATED(s_mp_mul_digs_fast) mp_err fast_s_mp_mul_digs(const mp_int *a, const mp_int *b, mp_int *c, + int digs); +MP_DEPRECATED(s_mp_mul_high_digs_fast) mp_err fast_s_mp_mul_high_digs(const mp_int *a, const mp_int *b, + mp_int *c, + int digs); +MP_DEPRECATED(s_mp_sqr_fast) mp_err fast_s_mp_sqr(const mp_int *a, mp_int *b); +MP_DEPRECATED(s_mp_balance_mul) mp_err mp_balance_mul(const mp_int *a, const mp_int *b, mp_int *c); +MP_DEPRECATED(s_mp_exptmod_fast) mp_err mp_exptmod_fast(const mp_int *G, const mp_int *X, const mp_int *P, + mp_int *Y, + int redmode); +MP_DEPRECATED(s_mp_invmod_slow) mp_err mp_invmod_slow(const mp_int *a, const mp_int *b, mp_int *c); +MP_DEPRECATED(s_mp_karatsuba_mul) mp_err mp_karatsuba_mul(const mp_int *a, const mp_int *b, mp_int *c); +MP_DEPRECATED(s_mp_karatsuba_sqr) mp_err mp_karatsuba_sqr(const mp_int *a, mp_int *b); +MP_DEPRECATED(s_mp_toom_mul) mp_err mp_toom_mul(const mp_int *a, const mp_int *b, mp_int *c); +MP_DEPRECATED(s_mp_toom_sqr) mp_err mp_toom_sqr(const mp_int *a, mp_int *b); +MP_DEPRECATED(s_mp_reverse) void bn_reverse(unsigned char *s, int len); + +#define MP_GET_ENDIANNESS(x) \ + do{\ + int16_t n = 0x1; \ + char *p = (char *)&n; \ + x = (p[0] == '\x01') ? MP_LITTLE_ENDIAN : MP_BIG_ENDIAN; \ + } while (0) + +/* code-generating macros */ +#define MP_SET_UNSIGNED(name, type) \ + void name(mp_int * a, type b) \ + { \ + int i = 0; \ + while (b != 0u) { \ + a->dp[i++] = ((mp_digit)b & MP_MASK); \ + if (MP_SIZEOF_BITS(type) <= MP_DIGIT_BIT) { break; } \ + b >>= ((MP_SIZEOF_BITS(type) <= MP_DIGIT_BIT) ? 0 : MP_DIGIT_BIT); \ + } \ + a->used = i; \ + a->sign = MP_ZPOS; \ + MP_ZERO_DIGITS(a->dp + a->used, a->alloc - a->used); \ + } + +#define MP_SET_SIGNED(name, uname, type, utype) \ + void name(mp_int * a, type b) \ + { \ + uname(a, (b < 0) ? -(utype)b : (utype)b); \ + if (b < 0) { a->sign = MP_NEG; } \ + } + +#define MP_INIT_INT(name , set, type) \ + mp_err name(mp_int * a, type b) \ + { \ + mp_err err; \ + if ((err = mp_init(a)) != MP_OKAY) { \ + return err; \ + } \ + set(a, b); \ + return MP_OKAY; \ + } + +#define MP_GET_MAG(name, type) \ + type name(const mp_int* a) \ + { \ + unsigned i = MP_MIN((unsigned)a->used, (unsigned)((MP_SIZEOF_BITS(type) + MP_DIGIT_BIT - 1) / MP_DIGIT_BIT)); \ + type res = 0u; \ + while (i --> 0u) { \ + res <<= ((MP_SIZEOF_BITS(type) <= MP_DIGIT_BIT) ? 0 : MP_DIGIT_BIT); \ + res |= (type)a->dp[i]; \ + if (MP_SIZEOF_BITS(type) <= MP_DIGIT_BIT) { break; } \ + } \ + return res; \ + } + +#define MP_GET_SIGNED(name, mag, type, utype) \ + type name(const mp_int* a) \ + { \ + utype res = mag(a); \ + return (a->sign == MP_NEG) ? (type)-res : (type)res; \ + } + +#endif |