88 lines
2.4 KiB
C
88 lines
2.4 KiB
C
|
/* $OpenBSD: arc4random_netbsd.h,v 1.3 2016/06/30 12:19:51 bcook Exp $ */
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Copyright (c) 1996, David Mazieres <dm@uun.org>
|
||
|
|
* Copyright (c) 2008, Damien Miller <djm@openbsd.org>
|
||
|
|
* Copyright (c) 2013, Markus Friedl <markus@openbsd.org>
|
||
|
|
* Copyright (c) 2014, Theo de Raadt <deraadt@openbsd.org>
|
||
|
|
*
|
||
|
|
* Permission to use, copy, modify, and distribute this software for any
|
||
|
|
* purpose with or without fee is hereby granted, provided that the above
|
||
|
|
* copyright notice and this permission notice appear in all copies.
|
||
|
|
*
|
||
|
|
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
|
||
|
|
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
||
|
|
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
|
||
|
|
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
||
|
|
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
||
|
|
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
|
||
|
|
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
||
|
|
*/
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Stub functions for portability.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <sys/mman.h>
|
||
|
|
|
||
|
|
#include <pthread.h>
|
||
|
|
#include <signal.h>
|
||
|
|
|
||
|
|
static pthread_mutex_t arc4random_mtx = PTHREAD_MUTEX_INITIALIZER;
|
||
|
|
#define _ARC4_LOCK() pthread_mutex_lock(&arc4random_mtx)
|
||
|
|
#define _ARC4_UNLOCK() pthread_mutex_unlock(&arc4random_mtx)
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Unfortunately, pthread_atfork() is broken on FreeBSD (at least 9 and 10) if
|
||
|
|
* a program does not link to -lthr. Callbacks registered with pthread_atfork()
|
||
|
|
* appear to fail silently. So, it is not always possible to detect a PID
|
||
|
|
* wraparound.
|
||
|
|
*/
|
||
|
|
#define _ARC4_ATFORK(f) pthread_atfork(NULL, NULL, (f))
|
||
|
|
|
||
|
|
static inline void
|
||
|
|
_getentropy_fail(void)
|
||
|
|
{
|
||
|
|
raise(SIGKILL);
|
||
|
|
}
|
||
|
|
|
||
|
|
static volatile sig_atomic_t _rs_forked;
|
||
|
|
|
||
|
|
static inline void
|
||
|
|
_rs_forkhandler(void)
|
||
|
|
{
|
||
|
|
_rs_forked = 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void
|
||
|
|
_rs_forkdetect(void)
|
||
|
|
{
|
||
|
|
static pid_t _rs_pid = 0;
|
||
|
|
pid_t pid = getpid();
|
||
|
|
|
||
|
|
if (_rs_pid == 0 || _rs_pid != pid || _rs_forked) {
|
||
|
|
_rs_pid = pid;
|
||
|
|
_rs_forked = 0;
|
||
|
|
if (rs)
|
||
|
|
memset(rs, 0, sizeof(*rs));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int
|
||
|
|
_rs_allocate(struct _rs **rsp, struct _rsx **rsxp)
|
||
|
|
{
|
||
|
|
if ((*rsp = mmap(NULL, sizeof(**rsp), PROT_READ|PROT_WRITE,
|
||
|
|
MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED)
|
||
|
|
return (-1);
|
||
|
|
|
||
|
|
if ((*rsxp = mmap(NULL, sizeof(**rsxp), PROT_READ|PROT_WRITE,
|
||
|
|
MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED) {
|
||
|
|
munmap(*rsp, sizeof(**rsp));
|
||
|
|
*rsp = NULL;
|
||
|
|
return (-1);
|
||
|
|
}
|
||
|
|
|
||
|
|
_ARC4_ATFORK(_rs_forkhandler);
|
||
|
|
return (0);
|
||
|
|
}
|