c63dab466c
Also some minor style cleanups.
135 lines
3.9 KiB
C
135 lines
3.9 KiB
C
/*-
|
|
* Copyright (c) 2000 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("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/types.h>
|
|
#include <sys/queue.h>
|
|
#include <sys/kthread.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/poll.h>
|
|
#include <sys/selinfo.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/random.h>
|
|
|
|
#include <machine/cpu.h>
|
|
|
|
#include <dev/random/randomdev.h>
|
|
|
|
static int read_random_phony(void *, int);
|
|
|
|
/* Structure holding the desired entropy sources */
|
|
struct harvest_select harvest = { 0, 0, 0 };
|
|
|
|
/* hold the address of the routine which is actually called if
|
|
* the randomdev is loaded
|
|
*/
|
|
static void (*reap_func)(u_int64_t, void *, u_int, u_int, u_int, enum esource)
|
|
= NULL;
|
|
static int (*read_func)(void *, int) = read_random_phony;
|
|
|
|
/* Initialise the harvester at load time */
|
|
void
|
|
random_init_harvester(void (*reaper)(u_int64_t, void *, u_int, u_int, u_int,
|
|
enum esource), int (*reader)(void *, int))
|
|
{
|
|
reap_func = reaper;
|
|
read_func = reader;
|
|
}
|
|
|
|
/* Deinitialise the harvester at unload time */
|
|
void
|
|
random_deinit_harvester(void)
|
|
{
|
|
reap_func = NULL;
|
|
read_func = read_random_phony;
|
|
}
|
|
|
|
/* Entropy harvesting routine. This is supposed to be fast; do
|
|
* not do anything slow in here!
|
|
* Implemented as in indirect call to allow non-inclusion of
|
|
* the entropy device.
|
|
*/
|
|
void
|
|
random_harvest(void *entropy, u_int count, u_int bits, u_int frac,
|
|
enum esource origin)
|
|
{
|
|
if (reap_func)
|
|
(*reap_func)(get_cyclecount(), entropy, count, bits, frac,
|
|
origin);
|
|
}
|
|
|
|
/* Userland-visible version of read_random */
|
|
int
|
|
read_random(void *buf, int count)
|
|
{
|
|
return (*read_func)(buf, count);
|
|
}
|
|
|
|
/* If the entropy device is not loaded, make a token effort to
|
|
* provide _some_ kind of randomness. This should only be used
|
|
* inside other RNG's, like arc4random(9).
|
|
*/
|
|
static int
|
|
read_random_phony(void *buf, int count)
|
|
{
|
|
u_long randval;
|
|
int size, i;
|
|
|
|
/* srandom() is called in kern/init_main.c:proc0_post() */
|
|
|
|
/* Fill buf[] with random(9) output */
|
|
for (i = 0; i < count; i+= (int)sizeof(u_long)) {
|
|
randval = random();
|
|
size = (count - i) < (int)sizeof(u_long)
|
|
? (count - i)
|
|
: sizeof(u_long);
|
|
memcpy(&((char *)buf)[i], &randval, (size_t)size);
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
/* Helper routine to enable kthread_exit() to work while the module is
|
|
* being (or has been) unloaded.
|
|
* This routine is in this file because it is always linked into the kernel,
|
|
* and will thus never be unloaded. This is critical for unloadable modules
|
|
* that have threads.
|
|
*/
|
|
void
|
|
random_set_wakeup_exit(void *control)
|
|
{
|
|
wakeup(control);
|
|
mtx_lock(&Giant);
|
|
kthread_exit(0);
|
|
/* NOTREACHED */
|
|
}
|