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Separate out the Software RNG entropy harvesting queue and thread into its own files.

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Submitted by:	 Arthur Mesh <arthurmesh@gmail.com>
This commit is contained in:
Mark Murray 2013-08-30 11:42:57 +00:00
parent f27c28dc6e
commit 77de2c3f58
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/projects/random_number_generator/; revision=255071
4 changed files with 298 additions and 198 deletions
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3
sys/conf/files
View File

@ -2032,8 +2032,9 @@ rt2860.fw optional rt2860fw | ralfw \
clean "rt2860.fw"
dev/random/harvest.c standard
dev/random/hash.c optional random
dev/random/random_adaptors.c standard
dev/random/pseudo_rng.c standard
dev/random/random_adaptors.c standard
dev/random/random_harvestq.c standard
dev/random/randomdev.c optional random
dev/random/randomdev_soft.c optional random
dev/random/yarrow.c optional random

251
sys/dev/random/random_harvestq.c Normal file
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@ -0,0 +1,251 @@
/*-
* Copyright (c) 2013 Arthur Mesh
* Copyright (c) 2000-2009 Mark R V Murray
* Copyright (c) 2004 Robert N. M. Watson
* 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.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/random.h>
#include <sys/sysctl.h>
#include <sys/unistd.h>
#include <dev/random/randomdev_soft.h>
#include "random_harvestq.h"
#define RANDOM_FIFO_MAX 256 /* How many events to queue up */
MALLOC_DEFINE(M_ENTROPY, "entropy", "Entropy harvesting buffers");
/*
* The harvest mutex protects the consistency of the entropy fifos and
* empty fifo.
*/
struct mtx harvest_mtx;
/* Lockable FIFO queue holding entropy buffers */
struct entropyfifo {
int count;
STAILQ_HEAD(harvestlist, harvest) head;
};
/* Empty entropy buffers */
static struct entropyfifo emptyfifo;
#define EMPTYBUFFERS 1024
/* Harvested entropy */
static struct entropyfifo harvestfifo[ENTROPYSOURCE];
/* <0 to end the kthread, 0 to let it run, 1 to flush the harvest queues */
int random_kthread_control = 0;
static struct proc *random_kthread_proc;
static void
random_kthread(void *arg)
{
STAILQ_HEAD(, harvest) local_queue;
struct harvest *event = NULL;
int local_count;
enum esource source;
event_proc_f func = arg;
STAILQ_INIT(&local_queue);
local_count = 0;
/* Process until told to stop */
mtx_lock_spin(&harvest_mtx);
for (; random_kthread_control >= 0;) {
/* Cycle through all the entropy sources */
for (source = RANDOM_START; source < ENTROPYSOURCE; source++) {
/*
* Drain entropy source records into a thread-local
* queue for processing while not holding the mutex.
*/
STAILQ_CONCAT(&local_queue, &harvestfifo[source].head);
local_count += harvestfifo[source].count;
harvestfifo[source].count = 0;
}
/*
* Deal with events, if any, dropping the mutex as we process
* each event. Then push the events back into the empty
* fifo.
*/
if (!STAILQ_EMPTY(&local_queue)) {
mtx_unlock_spin(&harvest_mtx);
STAILQ_FOREACH(event, &local_queue, next)
func(event);
mtx_lock_spin(&harvest_mtx);
STAILQ_CONCAT(&emptyfifo.head, &local_queue);
emptyfifo.count += local_count;
local_count = 0;
}
KASSERT(local_count == 0, ("random_kthread: local_count %d",
local_count));
/*
* If a queue flush was commanded, it has now happened,
* and we can mark this by resetting the command.
*/
if (random_kthread_control == 1)
random_kthread_control = 0;
/* Work done, so don't belabour the issue */
msleep_spin_sbt(&random_kthread_control, &harvest_mtx,
"-", SBT_1S / 10, 0, C_PREL(1));
}
mtx_unlock_spin(&harvest_mtx);
random_set_wakeup_exit(&random_kthread_control);
/* NOTREACHED */
}
void
random_harvestq_init(event_proc_f cb)
{
int error, i;
struct harvest *np;
enum esource e;
/* Initialise the harvest fifos */
STAILQ_INIT(&emptyfifo.head);
emptyfifo.count = 0;
for (i = 0; i < EMPTYBUFFERS; i++) {
np = malloc(sizeof(struct harvest), M_ENTROPY, M_WAITOK);
STAILQ_INSERT_TAIL(&emptyfifo.head, np, next);
}
for (e = RANDOM_START; e < ENTROPYSOURCE; e++) {
STAILQ_INIT(&harvestfifo[e].head);
harvestfifo[e].count = 0;
}
mtx_init(&harvest_mtx, "entropy harvest mutex", NULL, MTX_SPIN);
/* Start the hash/reseed thread */
error = kproc_create(random_kthread, cb,
&random_kthread_proc, RFHIGHPID, 0, "rand_harvestq"); /* RANDOM_CSPRNG_NAME */
if (error != 0)
panic("Cannot create entropy maintenance thread.");
}
void
random_harvestq_deinit(void)
{
struct harvest *np;
enum esource e;
/* Destroy the harvest fifos */
while (!STAILQ_EMPTY(&emptyfifo.head)) {
np = STAILQ_FIRST(&emptyfifo.head);
STAILQ_REMOVE_HEAD(&emptyfifo.head, next);
free(np, M_ENTROPY);
}
for (e = RANDOM_START; e < ENTROPYSOURCE; e++) {
while (!STAILQ_EMPTY(&harvestfifo[e].head)) {
np = STAILQ_FIRST(&harvestfifo[e].head);
STAILQ_REMOVE_HEAD(&harvestfifo[e].head, next);
free(np, M_ENTROPY);
}
}
mtx_destroy(&harvest_mtx);
}
/*
* Entropy harvesting routine. This is supposed to be fast; do
* not do anything slow in here!
*/
void
random_harvestq_internal(u_int64_t somecounter, const void *entropy,
u_int count, u_int bits, u_int frac, enum esource origin)
{
struct harvest *event;
KASSERT(origin >= RANDOM_START && origin <= RANDOM_PURE,
("random_harvest_internal: origin %d invalid\n", origin));
/* Lockless read to avoid lock operations if fifo is full. */
if (harvestfifo[origin].count >= RANDOM_FIFO_MAX)
return;
mtx_lock_spin(&harvest_mtx);
/*
* Don't make the harvest queues too big - help to prevent low-grade
* entropy swamping
*/
if (harvestfifo[origin].count < RANDOM_FIFO_MAX) {
event = STAILQ_FIRST(&emptyfifo.head);
if (event != NULL) {
/* Add the harvested data to the fifo */
STAILQ_REMOVE_HEAD(&emptyfifo.head, next);
harvestfifo[origin].count++;
event->somecounter = somecounter;
event->size = count;
event->bits = bits;
event->frac = frac;
event->source = origin;
/* XXXX Come back and make this dynamic! */
count = MIN(count, HARVESTSIZE);
memcpy(event->entropy, entropy, count);
#if 0
{
int i;
printf("Harvest:%16jX ", event->somecounter);
for (i = 0; i < event->size; i++)
printf("%02X", event->entropy[i]);
for (; i < 16; i++)
printf(" ");
printf(" %2d 0x%2X.%03X %02X\n", event->size, event->bits, event->frac, event->source);
}
#endif
STAILQ_INSERT_TAIL(&harvestfifo[origin].head,
event, next);
}
}
mtx_unlock_spin(&harvest_mtx);
}

41
sys/dev/random/random_harvestq.h Normal file
View File

@ -0,0 +1,41 @@
/*-
* Copyright (c) 2013 Arthur Mesh <arthurmesh@gmail.com>
* 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.
*
* $FreeBSD$
*/
#ifndef __RANDOM_HARVEST_H__
#define __RANDOM_HARVEST_H__
typedef void (*event_proc_f)(struct harvest *event);
void random_harvestq_init(event_proc_f);
void random_harvestq_deinit(void);
void random_harvestq_internal(u_int64_t, const void *,
u_int, u_int, u_int, enum esource);
extern int random_kthread_control;
#endif /* __RANDOM_HARVEST_H__ */

201
sys/dev/random/randomdev_soft.c
View File

@ -37,17 +37,13 @@ __FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/poll.h>
#include <sys/proc.h>
#include <sys/random.h>
#include <sys/selinfo.h>
#include <sys/sysctl.h>
@ -67,11 +63,8 @@ __FBSDID("$FreeBSD$");
#include <dev/random/fortuna.h>
#endif
#define RANDOM_FIFO_MAX 256 /* How many events to queue up */
#include "random_harvestq.h"
static void random_kthread(void *);
static void random_harvest_internal(u_int64_t, const void *, u_int,
u_int, u_int, enum esource);
static int randomdev_poll(int event, struct thread *td);
static int randomdev_block(int flag);
static void randomdev_flush_reseed(void);
@ -109,33 +102,6 @@ static struct random_adaptor random_context = {
#endif
MALLOC_DEFINE(M_ENTROPY, "entropy", "Entropy harvesting buffers for " RANDOM_CSPRNG_NAME);
/*
* The harvest mutex protects the consistency of the entropy fifos and
* empty fifo.
*/
struct mtx harvest_mtx;
/* Lockable FIFO queue holding entropy buffers */
struct entropyfifo {
int count;
STAILQ_HEAD(harvestlist, harvest) head;
};
/* Empty entropy buffers */
static struct entropyfifo emptyfifo;
#define EMPTYBUFFERS 1024
/* Harvested entropy */
static struct entropyfifo harvestfifo[ENTROPYSOURCE];
/* <0 to end the kthread, 0 to let it run, 1 to flush the harvest queues */
static int random_kthread_control = 0;
static struct proc *random_kthread_proc;
/* List for the dynamic sysctls */
static struct sysctl_ctx_list random_clist;
@ -151,10 +117,7 @@ random_check_boolean(SYSCTL_HANDLER_ARGS)
void
randomdev_init(void)
{
int error, i;
struct harvest *np;
struct sysctl_oid *random_sys_o, *random_sys_harvest_o;
enum esource e;
#if defined(YARROW_RNG)
random_yarrow_init_alg(&random_clist);
@ -200,37 +163,16 @@ randomdev_init(void)
&harvest.swi, 0, random_check_boolean, "I",
"Harvest SWI entropy");
/* Initialise the harvest fifos */
STAILQ_INIT(&emptyfifo.head);
emptyfifo.count = 0;
for (i = 0; i < EMPTYBUFFERS; i++) {
np = malloc(sizeof(struct harvest), M_ENTROPY, M_WAITOK);
STAILQ_INSERT_TAIL(&emptyfifo.head, np, next);
}
for (e = RANDOM_START; e < ENTROPYSOURCE; e++) {
STAILQ_INIT(&harvestfifo[e].head);
harvestfifo[e].count = 0;
}
mtx_init(&harvest_mtx, "entropy harvest mutex", NULL, MTX_SPIN);
/* Start the hash/reseed thread */
error = kproc_create(random_kthread, NULL,
&random_kthread_proc, RFHIGHPID, 0, RANDOM_CSPRNG_NAME);
if (error != 0)
panic("Cannot create entropy maintenance thread.");
random_harvestq_init(random_process_event);
/* Register the randomness harvesting routine */
randomdev_init_harvester(random_harvest_internal,
randomdev_init_harvester(random_harvestq_internal,
random_context.read);
}
void
randomdev_deinit(void)
{
struct harvest *np;
enum esource e;
/* Deregister the randomness harvesting routine */
randomdev_deinit_harvester();
@ -240,20 +182,6 @@ randomdev_deinit(void)
random_kthread_control = -1;
tsleep((void *)&random_kthread_control, 0, "term", 0);
/* Destroy the harvest fifos */
while (!STAILQ_EMPTY(&emptyfifo.head)) {
np = STAILQ_FIRST(&emptyfifo.head);
STAILQ_REMOVE_HEAD(&emptyfifo.head, next);
free(np, M_ENTROPY);
}
for (e = RANDOM_START; e < ENTROPYSOURCE; e++) {
while (!STAILQ_EMPTY(&harvestfifo[e].head)) {
np = STAILQ_FIRST(&harvestfifo[e].head);
STAILQ_REMOVE_HEAD(&harvestfifo[e].head, next);
free(np, M_ENTROPY);
}
}
#if defined(YARROW_RNG)
random_yarrow_deinit_alg();
#endif
@ -261,130 +189,9 @@ randomdev_deinit(void)
random_fortuna_deinit_alg();
#endif
mtx_destroy(&harvest_mtx);
sysctl_ctx_free(&random_clist);
}
/* ARGSUSED */
static void
random_kthread(void *arg __unused)
{
STAILQ_HEAD(, harvest) local_queue;
struct harvest *event = NULL;
int local_count;
enum esource source;
STAILQ_INIT(&local_queue);
local_count = 0;
/* Process until told to stop */
mtx_lock_spin(&harvest_mtx);
for (; random_kthread_control >= 0;) {
/* Cycle through all the entropy sources */
for (source = RANDOM_START; source < ENTROPYSOURCE; source++) {
/*
* Drain entropy source records into a thread-local
* queue for processing while not holding the mutex.
*/
STAILQ_CONCAT(&local_queue, &harvestfifo[source].head);
local_count += harvestfifo[source].count;
harvestfifo[source].count = 0;
}
/*
* Deal with events, if any, dropping the mutex as we process
* each event. Then push the events back into the empty
* fifo.
*/
if (!STAILQ_EMPTY(&local_queue)) {
mtx_unlock_spin(&harvest_mtx);
STAILQ_FOREACH(event, &local_queue, next)
random_process_event(event);
mtx_lock_spin(&harvest_mtx);
STAILQ_CONCAT(&emptyfifo.head, &local_queue);
emptyfifo.count += local_count;
local_count = 0;
}
KASSERT(local_count == 0, ("random_kthread: local_count %d",
local_count));
/*
* If a queue flush was commanded, it has now happened,
* and we can mark this by resetting the command.
*/
if (random_kthread_control == 1)
random_kthread_control = 0;
/* Work done, so don't belabour the issue */
msleep_spin_sbt(&random_kthread_control, &harvest_mtx,
"-", SBT_1S / 10, 0, C_PREL(1));
}
mtx_unlock_spin(&harvest_mtx);
random_set_wakeup_exit(&random_kthread_control);
/* NOTREACHED */
}
/* Entropy harvesting routine. This is supposed to be fast; do
* not do anything slow in here!
*/
static void
random_harvest_internal(u_int64_t somecounter, const void *entropy,
u_int count, u_int bits, u_int frac, enum esource origin)
{
struct harvest *event;
KASSERT(origin >= RANDOM_START && origin <= RANDOM_PURE,
("random_harvest_internal: origin %d invalid\n", origin));
/* Lockless read to avoid lock operations if fifo is full. */
if (harvestfifo[origin].count >= RANDOM_FIFO_MAX)
return;
mtx_lock_spin(&harvest_mtx);
/*
* Don't make the harvest queues too big - help to thwart low-grade
* entropy swamping
*/
if (harvestfifo[origin].count < RANDOM_FIFO_MAX) {
event = STAILQ_FIRST(&emptyfifo.head);
if (event != NULL) {
count = MIN(count, HARVESTSIZE);
/* Add the harvested data to the fifo */
STAILQ_REMOVE_HEAD(&emptyfifo.head, next);
harvestfifo[origin].count++;
event->somecounter = somecounter;
event->size = count;
event->bits = bits;
event->frac = frac;
event->source = origin;
memcpy(event->entropy, entropy, count);
#if 1
{
int i;
printf("Harvest:%16jX ", event->somecounter);
for (i = 0; i < event->size; i++)
printf("%02X", event->entropy[i]);
for (; i < 16; i++)
printf(" ");
printf(" %2d 0x%2X.%03X %02X\n", event->size, event->bits, event->frac, event->source);
}
#endif
STAILQ_INSERT_TAIL(&harvestfifo[origin].head,
event, next);
}
}
mtx_unlock_spin(&harvest_mtx);
}
void
randomdev_write(void *buf, int count)
{
@ -399,7 +206,7 @@ randomdev_write(void *buf, int count)
chunk = HARVESTSIZE;
if (i + chunk >= count)
chunk = (u_int)(count - i);
random_harvest_internal(get_cyclecount(), (char *)buf + i,
random_harvestq_internal(get_cyclecount(), (char *)buf + i,
chunk, 0, 0, RANDOM_WRITE);
}
}