opnsense-src/sys/compat/linuxkpi/common/include/linux/random.h
Warner Losh 95ee2897e9 sys: Remove $FreeBSD$: two-line .h pattern
Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/
2023-08-16 11:54:11 -06:00

105 lines
2.8 KiB
C

/*-
* Copyright (c) 2010 Isilon Systems, Inc.
* Copyright (c) 2010 iX Systems, Inc.
* Copyright (c) 2010 Panasas, Inc.
* Copyright (c) 2013-2016 Mellanox Technologies, Ltd.
* All rights reserved.
* Copyright 2023 The FreeBSD Foundation
*
* Portions of this software was developed by Björn Zeeb
* under sponsorship from the FreeBSD Foundation.
*
* 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 unmodified, 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 ``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 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.
*/
#ifndef _LINUXKPI_LINUX_RANDOM_H_
#define _LINUXKPI_LINUX_RANDOM_H_
#include <linux/types.h>
#include <sys/random.h>
#include <sys/libkern.h>
static inline void
get_random_bytes(void *buf, int nbytes)
{
arc4random_buf(buf, nbytes);
}
static inline u_int
get_random_int(void)
{
u_int val;
get_random_bytes(&val, sizeof(val));
return (val);
}
#define get_random_u32() get_random_int()
/*
* See "Fast Random Integer Generation in an Interval" by Daniel Lemire
* [https://arxiv.org/pdf/1805.10941.pdf] for implementation insights.
*/
static inline uint32_t
get_random_u32_inclusive(uint32_t floor, uint32_t ceil)
{
uint64_t x;
uint32_t t, v;
MPASS(ceil >= floor);
v = get_random_u32();
t = ceil - floor + 1;
x = (uint64_t)t * v;
while (x < t)
x = (uint64_t)t * get_random_u32();
v = x >> 32;
return (floor + v);
}
static inline u_long
get_random_long(void)
{
u_long val;
get_random_bytes(&val, sizeof(val));
return (val);
}
static __inline uint32_t
prandom_u32(void)
{
uint32_t val;
get_random_bytes(&val, sizeof(val));
return (val);
}
static inline u32
prandom_u32_max(u32 max)
{
return (arc4random_uniform(max));
}
#endif /* _LINUXKPI_LINUX_RANDOM_H_ */