Commit a58a91eb authored by Paul Sokolovsky's avatar Paul Sokolovsky
Browse files

extmod/modurandom: Add "urandom" module.

Seedable and reproducible pseudo-random number generator. Implemented
functions are getrandbits(n) (n <= 32) and seed().

The algorithm used is Yasmarang by Ilya Levin:
http://www.literatecode.com/yasmarang
parent e7bee6b3
/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2016 Paul Sokolovsky
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <assert.h>
#include <string.h>
//#include "py/nlr.h"
#include "py/runtime.h"
#if MICROPY_PY_URANDOM
// Yasmarang random number generator
// by Ilya Levin
// http://www.literatecode.com/yasmarang
// Public Domain
STATIC uint32_t yasmarang_pad = 0xeda4baba, yasmarang_n = 69, yasmarang_d = 233;
STATIC uint8_t yasmarang_dat = 0;
uint32_t yasmarang(void)
{
yasmarang_pad += yasmarang_dat + yasmarang_d * yasmarang_n;
yasmarang_pad = (yasmarang_pad<<3) + (yasmarang_pad>>29);
yasmarang_n = yasmarang_pad | 2;
yasmarang_d ^= (yasmarang_pad<<31) + (yasmarang_pad>>1);
yasmarang_dat ^= (char) yasmarang_pad ^ (yasmarang_d>>8) ^ 1;
return (yasmarang_pad^(yasmarang_d<<5)^(yasmarang_pad>>18)^(yasmarang_dat<<1));
} /* yasmarang */
// End of Yasmarang
STATIC mp_obj_t mod_urandom_getrandbits(mp_obj_t num_in) {
int n = mp_obj_get_int(num_in);
if (n > 32 || n == 0) {
nlr_raise(mp_obj_new_exception(&mp_type_ValueError));
}
uint32_t mask = ~0;
// Beware of C undefined behavior when shifting by >= than bit size
mask >>= (32 - n);
return mp_obj_new_int_from_uint(yasmarang() & mask);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_urandom_getrandbits_obj, mod_urandom_getrandbits);
STATIC mp_obj_t mod_urandom_seed(mp_obj_t seed_in) {
mp_uint_t seed = mp_obj_get_int_truncated(seed_in);
yasmarang_pad = seed;
yasmarang_n = 69;
yasmarang_d = 233;
yasmarang_dat = 0;
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_urandom_seed_obj, mod_urandom_seed);
STATIC const mp_rom_map_elem_t mp_module_urandom_globals_table[] = {
{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_urandom) },
{ MP_ROM_QSTR(MP_QSTR_getrandbits), MP_ROM_PTR(&mod_urandom_getrandbits_obj) },
{ MP_ROM_QSTR(MP_QSTR_seed), MP_ROM_PTR(&mod_urandom_seed_obj) },
};
STATIC MP_DEFINE_CONST_DICT(mp_module_urandom_globals, mp_module_urandom_globals_table);
const mp_obj_module_t mp_module_urandom = {
.base = { &mp_type_module },
.name = MP_QSTR_urandom,
.globals = (mp_obj_dict_t*)&mp_module_urandom_globals,
};
#endif //MICROPY_PY_URANDOM
......@@ -101,6 +101,7 @@ extern const mp_obj_module_t mp_module_ure;
extern const mp_obj_module_t mp_module_uheapq;
extern const mp_obj_module_t mp_module_uhashlib;
extern const mp_obj_module_t mp_module_ubinascii;
extern const mp_obj_module_t mp_module_urandom;
extern const mp_obj_module_t mp_module_ussl;
extern const mp_obj_module_t mp_module_machine;
extern const mp_obj_module_t mp_module_lwip;
......
......@@ -783,6 +783,10 @@ typedef double mp_float_t;
#define MICROPY_PY_UBINASCII (0)
#endif
#ifndef MICROPY_PY_URANDOM
#define MICROPY_PY_URANDOM (0)
#endif
#ifndef MICROPY_PY_MACHINE
#define MICROPY_PY_MACHINE (0)
#endif
......
......@@ -184,6 +184,9 @@ STATIC const mp_rom_map_elem_t mp_builtin_module_table[] = {
#if MICROPY_PY_UBINASCII
{ MP_ROM_QSTR(MP_QSTR_ubinascii), MP_ROM_PTR(&mp_module_ubinascii) },
#endif
#if MICROPY_PY_URANDOM
{ MP_ROM_QSTR(MP_QSTR_urandom), MP_ROM_PTR(&mp_module_urandom) },
#endif
#if MICROPY_PY_USSL
{ MP_ROM_QSTR(MP_QSTR_ussl), MP_ROM_PTR(&mp_module_ussl) },
#endif
......
......@@ -168,6 +168,7 @@ PY_O_BASENAME = \
../extmod/modubinascii.o \
../extmod/machine_mem.o \
../extmod/modussl.o \
../extmod/modurandom.o \
../extmod/fsusermount.o \
../extmod/moduos_dupterm.o \
......
......@@ -671,3 +671,9 @@ Q(count)
#if MICROPY_PY_OS_DUPTERM
Q(dupterm)
#endif
#if MICROPY_PY_URANDOM
Q(urandom)
Q(getrandbits)
Q(seed)
#endif
......@@ -79,6 +79,7 @@
#define MICROPY_PY_IO (1)
#define MICROPY_PY_IO_FILEIO (1)
#define MICROPY_PY_UBINASCII (1)
#define MICROPY_PY_URANDOM (1)
#define MICROPY_PY_UCTYPES (1)
#define MICROPY_PY_UZLIB (1)
#define MICROPY_PY_UJSON (1)
......
......@@ -104,6 +104,7 @@
#define MICROPY_PY_UHEAPQ (1)
#define MICROPY_PY_UHASHLIB (1)
#define MICROPY_PY_UBINASCII (1)
#define MICROPY_PY_URANDOM (1)
#ifndef MICROPY_PY_USELECT
#define MICROPY_PY_USELECT (1)
#endif
......
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