63edd2efc3
to dummy,yarrow and break the usability of /dev/random. Fix the name of the tunable to something logical that 'sysctl kern.random' emits. Submitted by: des@ (the idea, code by me)
300 lines
8.4 KiB
C
300 lines
8.4 KiB
C
/*-
|
|
* Copyright (c) 2000-2013 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.
|
|
*
|
|
*/
|
|
|
|
#include "opt_random.h"
|
|
|
|
#if !defined(RANDOM_YARROW) && !defined(RANDOM_FORTUNA)
|
|
#define RANDOM_YARROW
|
|
#elif defined(RANDOM_YARROW) && defined(RANDOM_FORTUNA)
|
|
#error "Must define either RANDOM_YARROW or RANDOM_FORTUNA"
|
|
#endif
|
|
#if defined(RANDOM_FORTUNA)
|
|
#error "Fortuna is not yet implemented"
|
|
#endif
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/fcntl.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/module.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/poll.h>
|
|
#include <sys/random.h>
|
|
#include <sys/selinfo.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/uio.h>
|
|
#include <sys/unistd.h>
|
|
|
|
#include <machine/bus.h>
|
|
#include <machine/cpu.h>
|
|
|
|
#include <dev/random/randomdev.h>
|
|
#include <dev/random/randomdev_soft.h>
|
|
#include <dev/random/random_harvestq.h>
|
|
#include <dev/random/random_adaptors.h>
|
|
#if defined(RANDOM_YARROW)
|
|
#include <dev/random/yarrow.h>
|
|
#endif
|
|
#if defined(RANDOM_FORTUNA)
|
|
#include <dev/random/fortuna.h>
|
|
#endif
|
|
|
|
|
|
static int randomdev_poll(int event, struct thread *td);
|
|
static int randomdev_block(int flag);
|
|
static void randomdev_flush_reseed(void);
|
|
|
|
#if defined(RANDOM_YARROW)
|
|
static struct random_adaptor random_context = {
|
|
.ident = "Software, Yarrow",
|
|
.init = randomdev_init,
|
|
.deinit = randomdev_deinit,
|
|
.block = randomdev_block,
|
|
.read = random_yarrow_read,
|
|
.poll = randomdev_poll,
|
|
.reseed = randomdev_flush_reseed,
|
|
.seeded = 0, /* This will be seeded during entropy processing */
|
|
.priority = 90, /* High priority, so top of the list. Fortuna may still win. */
|
|
};
|
|
#define RANDOM_MODULE_NAME yarrow
|
|
#define RANDOM_CSPRNG_NAME "yarrow"
|
|
#endif
|
|
|
|
#if defined(RANDOM_FORTUNA)
|
|
static struct random_adaptor random_context = {
|
|
.ident = "Software, Fortuna",
|
|
.init = randomdev_init,
|
|
.deinit = randomdev_deinit,
|
|
.block = randomdev_block,
|
|
.read = random_fortuna_read,
|
|
.poll = randomdev_poll,
|
|
.reseed = randomdev_flush_reseed,
|
|
.seeded = 0, /* This will be excplicitly seeded at startup when secured */
|
|
.priority = 100, /* High priority, so top of the list. Beat Yarrow. */
|
|
};
|
|
#define RANDOM_MODULE_NAME fortuna
|
|
#define RANDOM_CSPRNG_NAME "fortuna"
|
|
#endif
|
|
|
|
TUNABLE_INT("kern.random.sys.seeded", &random_context.seeded);
|
|
|
|
/* List for the dynamic sysctls */
|
|
static struct sysctl_ctx_list random_clist;
|
|
|
|
/* ARGSUSED */
|
|
static int
|
|
random_check_boolean(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
if (oidp->oid_arg1 != NULL && *(u_int *)(oidp->oid_arg1) != 0)
|
|
*(u_int *)(oidp->oid_arg1) = 1;
|
|
return (sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req));
|
|
}
|
|
|
|
void
|
|
randomdev_init(void)
|
|
{
|
|
struct sysctl_oid *random_sys_o, *random_sys_harvest_o;
|
|
|
|
#if defined(RANDOM_YARROW)
|
|
random_yarrow_init_alg(&random_clist);
|
|
#endif
|
|
#if defined(RANDOM_FORTUNA)
|
|
random_fortuna_init_alg(&random_clist);
|
|
#endif
|
|
|
|
random_sys_o = SYSCTL_ADD_NODE(&random_clist,
|
|
SYSCTL_STATIC_CHILDREN(_kern_random),
|
|
OID_AUTO, "sys", CTLFLAG_RW, 0,
|
|
"Entropy Device Parameters");
|
|
|
|
SYSCTL_ADD_PROC(&random_clist,
|
|
SYSCTL_CHILDREN(random_sys_o),
|
|
OID_AUTO, "seeded", CTLTYPE_INT | CTLFLAG_RW,
|
|
&random_context.seeded, 0, random_check_boolean, "I",
|
|
"Seeded State");
|
|
|
|
random_sys_harvest_o = SYSCTL_ADD_NODE(&random_clist,
|
|
SYSCTL_CHILDREN(random_sys_o),
|
|
OID_AUTO, "harvest", CTLFLAG_RW, 0,
|
|
"Entropy Sources");
|
|
|
|
SYSCTL_ADD_PROC(&random_clist,
|
|
SYSCTL_CHILDREN(random_sys_harvest_o),
|
|
OID_AUTO, "ethernet", CTLTYPE_INT | CTLFLAG_RW,
|
|
&harvest.ethernet, 1, random_check_boolean, "I",
|
|
"Harvest NIC entropy");
|
|
SYSCTL_ADD_PROC(&random_clist,
|
|
SYSCTL_CHILDREN(random_sys_harvest_o),
|
|
OID_AUTO, "point_to_point", CTLTYPE_INT | CTLFLAG_RW,
|
|
&harvest.point_to_point, 1, random_check_boolean, "I",
|
|
"Harvest serial net entropy");
|
|
SYSCTL_ADD_PROC(&random_clist,
|
|
SYSCTL_CHILDREN(random_sys_harvest_o),
|
|
OID_AUTO, "interrupt", CTLTYPE_INT | CTLFLAG_RW,
|
|
&harvest.interrupt, 1, random_check_boolean, "I",
|
|
"Harvest IRQ entropy");
|
|
SYSCTL_ADD_PROC(&random_clist,
|
|
SYSCTL_CHILDREN(random_sys_harvest_o),
|
|
OID_AUTO, "swi", CTLTYPE_INT | CTLFLAG_RW,
|
|
&harvest.swi, 1, random_check_boolean, "I",
|
|
"Harvest SWI entropy");
|
|
|
|
random_harvestq_init(random_process_event);
|
|
|
|
/* Register the randomness harvesting routine */
|
|
randomdev_init_harvester(random_harvestq_internal,
|
|
random_context.read);
|
|
}
|
|
|
|
void
|
|
randomdev_deinit(void)
|
|
{
|
|
/* Deregister the randomness harvesting routine */
|
|
randomdev_deinit_harvester();
|
|
|
|
/*
|
|
* Command the hash/reseed thread to end and wait for it to finish
|
|
*/
|
|
random_kthread_control = -1;
|
|
tsleep((void *)&random_kthread_control, 0, "term", 0);
|
|
|
|
#if defined(RANDOM_YARROW)
|
|
random_yarrow_deinit_alg();
|
|
#endif
|
|
#if defined(RANDOM_FORTUNA)
|
|
random_fortuna_deinit_alg();
|
|
#endif
|
|
|
|
sysctl_ctx_free(&random_clist);
|
|
}
|
|
|
|
void
|
|
randomdev_unblock(void)
|
|
{
|
|
if (!random_context.seeded) {
|
|
selwakeuppri(&random_context.rsel, PUSER);
|
|
wakeup(&random_context);
|
|
printf("random: unblocking device.\n");
|
|
random_context.seeded = 1;
|
|
}
|
|
/* Do arc4random(9) a favour while we are about it. */
|
|
(void)atomic_cmpset_int(&arc4rand_iniseed_state, ARC4_ENTR_NONE,
|
|
ARC4_ENTR_HAVE);
|
|
}
|
|
|
|
static int
|
|
randomdev_poll(int events, struct thread *td)
|
|
{
|
|
int revents = 0;
|
|
|
|
mtx_lock(&random_reseed_mtx);
|
|
|
|
if (random_context.seeded)
|
|
revents = events & (POLLIN | POLLRDNORM);
|
|
else
|
|
selrecord(td, &random_context.rsel);
|
|
|
|
mtx_unlock(&random_reseed_mtx);
|
|
return (revents);
|
|
}
|
|
|
|
static int
|
|
randomdev_block(int flag)
|
|
{
|
|
int error = 0;
|
|
|
|
mtx_lock(&random_reseed_mtx);
|
|
|
|
/* Blocking logic */
|
|
while (!random_context.seeded && !error) {
|
|
if (flag & O_NONBLOCK)
|
|
error = EWOULDBLOCK;
|
|
else {
|
|
printf("random: blocking on read.\n");
|
|
error = msleep(&random_context,
|
|
&random_reseed_mtx,
|
|
PUSER | PCATCH, "block", 0);
|
|
}
|
|
}
|
|
mtx_unlock(&random_reseed_mtx);
|
|
|
|
return (error);
|
|
}
|
|
|
|
/* Helper routine to perform explicit reseeds */
|
|
static void
|
|
randomdev_flush_reseed(void)
|
|
{
|
|
/* Command a entropy queue flush and wait for it to finish */
|
|
random_kthread_control = 1;
|
|
while (random_kthread_control)
|
|
pause("-", hz / 10);
|
|
|
|
#if defined(RANDOM_YARROW)
|
|
/* This ultimately calls randomdev_unblock() */
|
|
random_yarrow_reseed();
|
|
#endif
|
|
#if defined(RANDOM_FORTUNA)
|
|
/* This ultimately calls randomdev_unblock() */
|
|
random_fortuna_reseed();
|
|
#endif
|
|
}
|
|
|
|
static int
|
|
randomdev_modevent(module_t mod __unused, int type, void *unused __unused)
|
|
{
|
|
|
|
switch (type) {
|
|
case MOD_LOAD:
|
|
random_adaptor_register(RANDOM_CSPRNG_NAME, &random_context);
|
|
/*
|
|
* For statically built kernels that contain both device
|
|
* random and options PADLOCK_RNG/RDRAND_RNG/etc..,
|
|
* this event handler will do nothing, since the random
|
|
* driver-specific handlers are loaded after these HW
|
|
* consumers, and hence hasn't yet registered for this event.
|
|
*
|
|
* In case where both the random driver and RNG's are built
|
|
* as seperate modules, random.ko is loaded prior to *_rng.ko's
|
|
* (by dependency). This event handler is there to delay
|
|
* creation of /dev/{u,}random and attachment of this *_rng.ko.
|
|
*/
|
|
EVENTHANDLER_INVOKE(random_adaptor_attach, &random_context);
|
|
return (0);
|
|
}
|
|
|
|
return (EINVAL);
|
|
}
|
|
|
|
RANDOM_ADAPTOR_MODULE(RANDOM_MODULE_NAME, randomdev_modevent, 1);
|