1/*-
2 * Copyright (c) 2000-2013 Mark R V Murray
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer
10 *    in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 * $FreeBSD$
27 */
28
29#ifndef SYS_DEV_RANDOM_RANDOMDEV_SOFT_H_INCLUDED
30#define SYS_DEV_RANDOM_RANDOMDEV_SOFT_H_INCLUDED
31
32/* This header contains only those definitions that are global
33 * and harvester-specific for the entropy processor
34 */
35
36/* #define ENTROPYSOURCE nn	   entropy sources (actually classes)
37 *					This is properly defined in
38 *					an enum in sys/random.h
39 */
40
41/* The ring size _MUST_ be a power of 2 */
42#define HARVEST_RING_SIZE	1024	/* harvest ring buffer size */
43#define HARVEST_RING_MASK	(HARVEST_RING_SIZE - 1)
44
45#define HARVESTSIZE	16	/* max size of each harvested entropy unit */
46
47/* These are used to queue harvested packets of entropy. The entropy
48 * buffer size is pretty arbitrary.
49 */
50struct harvest {
51	uintmax_t somecounter;		/* fast counter for clock jitter */
52	uint8_t entropy[HARVESTSIZE];	/* the harvested entropy */
53	u_int size, bits;		/* stats about the entropy */
54	enum esource source;		/* origin of the entropy */
55	STAILQ_ENTRY(harvest) next;	/* next item on the list */
56};
57
58void randomdev_init(void);
59void randomdev_deinit(void);
60
61void randomdev_init_harvester(void (*)(u_int64_t, const void *, u_int,
62	u_int, enum esource), int (*)(void *, int));
63void randomdev_deinit_harvester(void);
64
65void random_set_wakeup_exit(void *);
66void random_process_event(struct harvest *event);
67void randomdev_unblock(void);
68
69extern struct mtx random_reseed_mtx;
70
71/* If this was C++, the macro below would be a template */
72#define RANDOM_CHECK_UINT(name, min, max)				\
73static int								\
74random_check_uint_##name(SYSCTL_HANDLER_ARGS)				\
75{									\
76	if (oidp->oid_arg1 != NULL) {					\
77		 if (*(u_int *)(oidp->oid_arg1) <= (min))		\
78			*(u_int *)(oidp->oid_arg1) = (min);		\
79		 else if (*(u_int *)(oidp->oid_arg1) > (max))		\
80			*(u_int *)(oidp->oid_arg1) = (max);		\
81	}								\
82        return (sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2,	\
83		req));							\
84}
85
86#endif
87