1
0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-21 11:13:30 +00:00
freebsd/sys/dev/random/probe.c
David E. O'Brien d0961945bb Refactor random_systat to be a *random_systat. This avoids unnecessary
structure copying in random_ident_hardware(). This change will also help
further modularization of random(4) subsystem.

Submitted by: arthurmesh@gmail.com
Reviewed by: obrien
Obtained from: Juniper Networks
2013-07-09 23:47:28 +00:00

94 lines
2.7 KiB
C

/*-
* Copyright (c) 2004 Mark R V Murray
* 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
* in this position and unchanged.
* 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.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#if defined(__amd64__) || (defined(__i386__) && !defined(PC98))
#include "opt_cpu.h"
#endif
#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/random.h>
#include <sys/selinfo.h>
#include <sys/sysctl.h>
#if defined(__amd64__) || (defined(__i386__) && !defined(PC98))
#include <machine/cpufunc.h>
#include <machine/cputypes.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>
#endif
#include <dev/random/randomdev.h>
#include <dev/random/randomdev_soft.h>
#if defined(__amd64__) || (defined(__i386__) && !defined(PC98))
#ifdef PADLOCK_RNG
extern struct random_systat random_nehemiah;
#endif
#ifdef RDRAND_RNG
extern struct random_systat random_ivy;
#endif
#endif
void
random_ident_hardware(struct random_systat **systat)
{
/* Set default to software */
*systat = &random_yarrow;
/* Then go looking for hardware */
#if defined(__amd64__) || (defined(__i386__) && !defined(PC98))
#ifdef PADLOCK_RNG
if (via_feature_rng & VIA_HAS_RNG) {
int enable;
enable = 1;
TUNABLE_INT_FETCH("hw.nehemiah_rng_enable", &enable);
if (enable)
*systat = &random_nehemiah;
}
#endif
#ifdef RDRAND_RNG
if (cpu_feature2 & CPUID2_RDRAND) {
int enable;
enable = 1;
TUNABLE_INT_FETCH("hw.ivy_rng_enable", &enable);
if (enable)
*systat = &random_ivy;
}
#endif
#endif
}