yarrow.h revision 72364 
1/*-
2 * Copyright (c) 2000 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: head/sys/dev/random/yarrow.h 72364 2001-02-11 16:21:35Z markm $
27 */
28
29/* #define ENTROPYSOURCE nn	   entropy sources (actually classes)
30 *					This is properly defined in
31 *					an enum in sys/random.h
32 */
33
34/* The ring size _MUST_ be a power of 2 */
35#define HARVEST_RING_SIZE	1024	/* harvest ring buffer size */
36#define HARVEST_RING_MASK	(HARVEST_RING_SIZE - 1)
37
38#define TIMEBIN		16	/* max value for Pt/t */
39
40#define HARVESTSIZE	16	/* max size of each harvested entropy unit */
41
42#define FAST		0
43#define SLOW		1
44
45int random_init(void);
46void random_deinit(void);
47void random_init_harvester(void (*)(u_int64_t, void *, u_int, u_int, u_int, enum esource), u_int (*)(void *, u_int));
48void random_deinit_harvester(void);
49void random_set_wakeup_exit(void *);
50
51void random_reseed(void);
52
53u_int read_random_real(void *, u_int);
54void write_random(void *, u_int);
55
56/* This is the beastie that needs protecting. It contains all of the
57 * state that we are excited about.
58 */
59struct random_state {
60	u_int64_t counter;	/* C */
61	struct yarrowkey key;	/* K */
62	int gengateinterval;	/* Pg */
63	int bins;		/* Pt/t */
64	int outputblocks;	/* count output blocks for gates */
65	u_int slowoverthresh;	/* slow pool overthreshhold reseed count */
66	struct pool {
67		struct source {
68			u_int bits;	/* estimated bits of entropy */
69			u_int frac;	/* fractional bits of entropy
70					   (given as 1024/n) */
71		} source[ENTROPYSOURCE];
72		u_int thresh;	/* pool reseed threshhold */
73		struct yarrowhash hash;	/* accumulated entropy */
74	} pool[2];		/* pool[0] is fast, pool[1] is slow */
75	int which;		/* toggle - shows the current insertion pool */
76	int seeded;		/* 0 causes blocking 1 allows normal output */
77	struct selinfo rsel;	/* For poll(2) */
78	u_char raw[HARVESTSIZE];/* Raw buffer for checking */
79};
80
81extern struct random_state random_state;
82