freebsd-skq/sys/dev/random/randomdev.c
kib f40a40f28a Fix random.ko module.
- Remove duplicated sources between standard part of the kernel and
  module.  In particular, it caused duplicated lock initialization and
  sysctl registration, both having bad consequences.
- Add missed source files to module.
- Static part of the kernel provides randomdev module, not
  random_adaptors.  Correct dependencies.
- Use cdev modules declaration macros.

Approved by:	secteam (delphij)
Reviewed by:	markm
2014-11-07 20:23:43 +00:00

245 lines
6.3 KiB
C

/*-
* Copyright (c) 2000-2013 Mark R V Murray
* 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.
*
*/
/*
* NOTE NOTE NOTE
*
* This file is compiled into the kernel unconditionally. Any random(4)
* infrastructure that needs to be in the kernel by default goes here!
*
* Except ...
*
* The adaptor code all goes into random_adaptor.c, which is also compiled
* the kernel by default. The module in that file is initialised before
* this one.
*
* Other modules must be initialised after the above two, and are
* software random processors which plug into random_adaptor.c.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_random.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/filio.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/random.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <sys/uio.h>
#include <sys/unistd.h>
#include <dev/random/randomdev.h>
#include <dev/random/random_adaptors.h>
#include <dev/random/random_harvestq.h>
#define RANDOM_MINOR 0
static d_ioctl_t randomdev_ioctl;
static struct cdevsw random_cdevsw = {
.d_name = "random",
.d_version = D_VERSION,
.d_read = random_adaptor_read,
.d_write = random_adaptor_write,
.d_poll = random_adaptor_poll,
.d_ioctl = randomdev_ioctl,
};
/* For use with make_dev(9)/destroy_dev(9). */
static struct cdev *random_dev;
/* Set up the sysctl root node for the entropy device */
SYSCTL_NODE(_kern, OID_AUTO, random, CTLFLAG_RW, 0, "Random Number Generator");
MALLOC_DEFINE(M_ENTROPY, "entropy", "Entropy harvesting buffers and data structures");
/* ARGSUSED */
static int
randomdev_ioctl(struct cdev *dev __unused, u_long cmd, caddr_t addr __unused,
int flags __unused, struct thread *td __unused)
{
int error = 0;
switch (cmd) {
/* Really handled in upper layer */
case FIOASYNC:
case FIONBIO:
break;
default:
error = ENOTTY;
}
return (error);
}
/* Helper routine to enable kproc_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
randomdev_set_wakeup_exit(void *control)
{
wakeup(control);
kproc_exit(0);
/* NOTREACHED */
}
/* ARGSUSED */
static int
randomdev_modevent(module_t mod __unused, int type, void *data __unused)
{
int error = 0;
switch (type) {
case MOD_LOAD:
printf("random: entropy device infrastructure driver\n");
random_dev = make_dev_credf(MAKEDEV_ETERNAL_KLD, &random_cdevsw,
RANDOM_MINOR, NULL, UID_ROOT, GID_WHEEL, 0644, "random");
make_dev_alias(random_dev, "urandom"); /* compatibility */
random_adaptors_init();
break;
case MOD_UNLOAD:
random_adaptors_deinit();
destroy_dev(random_dev);
break;
case MOD_SHUTDOWN:
break;
default:
error = EOPNOTSUPP;
break;
}
return (error);
}
DEV_MODULE_ORDERED(randomdev, randomdev_modevent, NULL, SI_ORDER_SECOND);
MODULE_VERSION(randomdev, 1);
/* ================
* Harvesting stubs
* ================
*/
/* Internal stub/fake routine for when no entropy processor is loaded.
* If the entropy device is not loaded, don't act on harvesting calls
* and just return.
*/
/* ARGSUSED */
static void
random_harvest_phony(const void *entropy __unused, u_int count __unused,
u_int bits __unused, enum random_entropy_source origin __unused)
{
}
/* Hold the address of the routine which is actually called */
static void (*reap_func)(const void *, u_int, u_int, enum random_entropy_source) = random_harvest_phony;
/* Initialise the harvester when/if it is loaded */
void
randomdev_init_harvester(void (*reaper)(const void *, u_int, u_int, enum random_entropy_source))
{
reap_func = reaper;
}
/* Deinitialise the harvester when/if it is unloaded */
void
randomdev_deinit_harvester(void)
{
reap_func = random_harvest_phony;
}
/* Entropy harvesting routine.
* Implemented as in indirect call to allow non-inclusion of
* the entropy device.
*/
void
random_harvest(const void *entropy, u_int count, u_int bits, enum random_entropy_source origin)
{
(*reap_func)(entropy, count, bits, origin);
}
/* ================================
* Internal reading stubs and fakes
* ================================
*/
/* Hold the address of the routine which is actually called */
static u_int (*read_func)(uint8_t *, u_int) = dummy_random_read_phony;
/* Initialise the reader when/if it is loaded */
void
randomdev_init_reader(u_int (*reader)(uint8_t *, u_int))
{
read_func = reader;
}
/* Deinitialise the reader when/if it is unloaded */
void
randomdev_deinit_reader(void)
{
read_func = dummy_random_read_phony;
}
/* Kernel API version of read_random().
* Implemented as in indirect call to allow non-inclusion of
* the entropy device.
*/
int
read_random(void *buf, int count)
{
return ((int)(*read_func)(buf, (u_int)count));
}