1/*- 2 * Copyright (c) 2004 Mark R V Murray 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer 10 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 */ 27 28#include <sys/cdefs.h> 29__FBSDID("$FreeBSD$"); 30 31#if defined(__amd64__) || (defined(__i386__) && !defined(PC98)) 32#include "opt_cpu.h" 33#endif 34 35#include <sys/types.h> 36#include <sys/param.h> 37#include <sys/systm.h> 38#include <sys/kernel.h> 39#include <sys/malloc.h> 40#include <sys/random.h> 41#include <sys/selinfo.h> 42#include <sys/sysctl.h> 43 44#if defined(__amd64__) || (defined(__i386__) && !defined(PC98)) 45#include <machine/cpufunc.h> 46#include <machine/cputypes.h> 47#include <machine/md_var.h> 48#include <machine/specialreg.h> 49#endif 50 51#include <dev/random/randomdev.h> 52#include <dev/random/randomdev_soft.h> 53 54#if defined(__amd64__) || (defined(__i386__) && !defined(PC98)) 55#ifdef PADLOCK_RNG 56extern struct random_systat random_nehemiah; 57#endif 58#ifdef RDRAND_RNG 59extern struct random_systat random_ivy; 60#endif 61#endif 62 63void 64random_ident_hardware(struct random_systat *systat) 65{ 66 67 /* Set default to software */ 68 *systat = random_yarrow; 69 70 /* Then go looking for hardware */ 71#if defined(__amd64__) || (defined(__i386__) && !defined(PC98)) 72#ifdef PADLOCK_RNG 73 if (via_feature_rng & VIA_HAS_RNG) { 74 int enable; 75 76 enable = 0; 77 TUNABLE_INT_FETCH("hw.nehemiah_rng_enable", &enable); 78 if (enable) 79 *systat = random_nehemiah; 80 } 81#endif 82#ifdef RDRAND_RNG 83 if (cpu_feature2 & CPUID2_RDRAND) { 84 int enable; 85 86 enable = 0; 87 TUNABLE_INT_FETCH("hw.ivy_rng_enable", &enable); 88 if (enable) 89 *systat = random_ivy; 90 } 91#endif 92#endif 93} 94