djsundog/circuitpython
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

unix/modos: Add support for uos.urandom(n).

Browse Source 
Use getrandom function if available, otherwise read from /dev/urandom.

Signed-off-by: Henk.Vergonet@gmail.com
This commit is contained in:
Henk Vergonet 2018-08-07 13:14:00 +02:00 committed by Damien George
parent 5ed7a748f0
commit d11ff0499f
1 changed files with 25 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
ports/unix/modos.c
View File

@ -27,6 +27,7 @@
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <stdio.h>
@ -49,6 +50,29 @@
#define USE_STATFS 1
#endif
#if defined(__GLIBC__) && defined(__GLIBC_PREREQ)
#if __GLIBC_PREREQ(2, 25)
#include <sys/random.h>
#define _HAVE_GETRANDOM
#endif
#endif
STATIC mp_obj_t mod_os_urandom(mp_obj_t num) {
mp_int_t n = mp_obj_get_int(num);
vstr_t vstr;
vstr_init_len(&vstr, n);
#ifdef _HAVE_GETRANDOM
RAISE_ERRNO(getrandom(vstr.buf, n, 0), errno);
#else
int fd = open("/dev/urandom", O_RDONLY);
RAISE_ERRNO(fd, errno);
RAISE_ERRNO(read(fd, vstr.buf, n), errno);
close(fd);
#endif
return mp_obj_new_str_from_vstr(&mp_type_bytes, &vstr);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_os_urandom_obj, mod_os_urandom);
STATIC mp_obj_t mod_os_stat(mp_obj_t path_in) {
struct stat sb;
const char *path = mp_obj_str_get_str(path_in);
@ -309,6 +333,7 @@ STATIC const mp_rom_map_elem_t mp_module_os_globals_table[] = {
{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_uos) },
{ MP_ROM_QSTR(MP_QSTR_errno), MP_ROM_PTR(&mod_os_errno_obj) },
{ MP_ROM_QSTR(MP_QSTR_stat), MP_ROM_PTR(&mod_os_stat_obj) },
{ MP_ROM_QSTR(MP_QSTR_urandom), MP_ROM_PTR(&mod_os_urandom_obj) },
#if MICROPY_PY_OS_STATVFS
{ MP_ROM_QSTR(MP_QSTR_statvfs), MP_ROM_PTR(&mod_os_statvfs_obj) },
#endif