/* Test module for verifying the correct operation of the
 * SP800-90A DRBG
 *
 * Use: compile, load into the kernel and observe dmesg
 *
 * Written by: Stephan Mueller <smueller@chronox.de>
 * Copyright (c) 2014
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 *                          NO WARRANTY
 *
 *  BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
 *  FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
 *  OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
 *  PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
 *  OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
 *  TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
 *  PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
 *  REPAIR OR CORRECTION.
 *
 *  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
 *  WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
 *  REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
 *  INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
 *  OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
 *  TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
 *  YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
 *  PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGES.
 */

#include <linux/random.h>
#include <linux/module.h>
#include <linux/slab.h> /* needed for kzalloc */

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>");
MODULE_DESCRIPTION("Test module for verifying the correct operation of async LRNG operation");

static struct random_work my_work;
static struct random_work my_work1;
static struct random_work my_work2;
static struct random_work my_work3;
static struct random_work my_work4;
static struct random_work my_work5;
static struct random_work my_work6;
static struct random_work my_work7;
static struct random_work my_work8;
static struct random_work my_work9;
#define LEN 1024
static char buffer[LEN];

void lrng_cb(void *buf, ssize_t buflen)
{
	printk("received %d bytes\n", (int)buflen);
}

static void cn(struct random_work *work)
{
	get_blocking_random_bytes_cancel(work);
	cancel_work_sync(&work->rw_work);
}

static int __init lrng_init(void)
{
	get_blocking_random_bytes_cb(NULL, &my_work, buffer, LEN, lrng_cb);
	get_blocking_random_bytes_cb(NULL, &my_work1, buffer, LEN, lrng_cb);
	get_blocking_random_bytes_cb(NULL, &my_work2, buffer, LEN, lrng_cb);
	get_blocking_random_bytes_cb(NULL, &my_work3, buffer, LEN, lrng_cb);
	get_blocking_random_bytes_cb(NULL, &my_work4, buffer, LEN, lrng_cb);
	get_blocking_random_bytes_cb(NULL, &my_work5, buffer, LEN, lrng_cb);
	get_blocking_random_bytes_cb(NULL, &my_work6, buffer, LEN, lrng_cb);
	get_blocking_random_bytes_cb(NULL, &my_work7, buffer, LEN, lrng_cb);
	get_blocking_random_bytes_cb(NULL, &my_work8, buffer, LEN, lrng_cb);
	get_blocking_random_bytes_cb(NULL, &my_work9, buffer, LEN, lrng_cb);

	/* cancel one work to see that work can be canceled independent from
	 * others */
	cn(&my_work);
	return 0;
}

void __exit lrng_exit(void)
{
	cn(&my_work1);
	cn(&my_work2);
	cn(&my_work3);
	cn(&my_work4);
	cn(&my_work5);
	cn(&my_work6);
	cn(&my_work7);
	cn(&my_work8);
	cn(&my_work9);
}

module_init(lrng_init);
module_exit(lrng_exit);