newlib-cygwin/newlib/libc/stdlib/arc4random.h

92 lines
2.5 KiB
C

/*-
* Copyright (c) 2016 embedded brains GmbH
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Newlib ports may override the default implementations via the following
* define and macros
* o _ARC4RANDOM_DATA,
* o _ARC4RANDOM_GETENTROPY_FAIL(),
* o _ARC4RANDOM_ALLOCATE(rsp, rspx), and
* o _ARC4RANDOM_FORKDETECT().
*/
#include <machine/_arc4random.h>
#include <sys/lock.h>
#include <signal.h>
#ifndef _ARC4_LOCK_INIT
#define _ARC4_LOCK_INIT __LOCK_INIT(static, __arc4random_mutex);
#define _ARC4_LOCK() __lock_acquire(__arc4random_mutex)
#define _ARC4_UNLOCK() __lock_release(__arc4random_mutex)
#endif /* _ARC4_LOCK_INIT */
#ifndef __SINGLE_THREAD__
_ARC4_LOCK_INIT
#endif
#ifdef _ARC4RANDOM_DATA
_ARC4RANDOM_DATA
#else
static struct {
struct _rs rs;
struct _rsx rsx;
} _arc4random_data;
#endif
static inline void
_getentropy_fail(void)
{
#ifdef _ARC4RANDOM_GETENTROPY_FAIL
_ARC4RANDOM_GETENTROPY_FAIL();
#else
raise(SIGKILL);
#endif
}
static inline int
_rs_allocate(struct _rs **rsp, struct _rsx **rsxp)
{
#ifdef _ARC4RANDOM_ALLOCATE
_ARC4RANDOM_ALLOCATE(rsp, rsxp);
#else
*rsp = &_arc4random_data.rs;
*rsxp = &_arc4random_data.rsx;
return (0);
#endif
}
static inline void
_rs_forkdetect(void)
{
#ifdef _ARC4RANDOM_FORKDETECT
_ARC4RANDOM_FORKDETECT();
#endif
}