randomdev.h revision 285422 
1/*-
2 * Copyright (c) 2000-2015 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/randomdev.h 285422 2015-07-12 18:14:38Z markm $
27 */
28
29#ifndef SYS_DEV_RANDOM_RANDOMDEV_H_INCLUDED
30#define	SYS_DEV_RANDOM_RANDOMDEV_H_INCLUDED
31
32#ifdef _KERNEL
33
34/* This header contains only those definitions that are global
35 * and non algorithm-specific for the entropy processor
36 */
37
38#ifdef SYSCTL_DECL	/* from sysctl.h */
39SYSCTL_DECL(_kern_random);
40
41#define	RANDOM_CHECK_UINT(name, min, max)				\
42static int								\
43random_check_uint_##name(SYSCTL_HANDLER_ARGS)				\
44{									\
45	if (oidp->oid_arg1 != NULL) {					\
46		if (*(u_int *)(oidp->oid_arg1) <= (min))		\
47			*(u_int *)(oidp->oid_arg1) = (min);		\
48		else if (*(u_int *)(oidp->oid_arg1) > (max))		\
49			*(u_int *)(oidp->oid_arg1) = (max);		\
50	}								\
51	return (sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2,	\
52		req));							\
53}
54#endif /* SYSCTL_DECL */
55
56MALLOC_DECLARE(M_ENTROPY);
57
58#define	RANDOM_ALG_READ_RATE_MINIMUM	32
59
60#endif /* _KERNEL */
61
62struct harvest_event;
63
64typedef void random_alg_pre_read_t(void);
65typedef void random_alg_read_t(uint8_t *, u_int);
66typedef void random_alg_write_t(uint8_t *, u_int);
67typedef int random_alg_seeded_t(void);
68typedef void random_alg_reseed_t(void);
69typedef void random_alg_eventprocessor_t(struct harvest_event *);
70
71typedef u_int random_source_read_t(void *, u_int);
72
73/*
74 * Random Algorithm is a processor of randomness for the kernel
75 * and for userland.
76 */
77struct random_algorithm {
78	const char			*ra_ident;
79	u_int				 ra_poolcount;
80	void				(*ra_init_alg)(void *);
81	void				(*ra_deinit_alg)(void *);
82	random_alg_pre_read_t		*ra_pre_read;
83	random_alg_read_t		*ra_read;
84	random_alg_write_t		*ra_write;
85	random_alg_reseed_t		*ra_reseed;
86	random_alg_seeded_t		*ra_seeded;
87	random_alg_eventprocessor_t	*ra_event_processor;
88};
89
90extern struct random_algorithm random_alg_context;
91
92#ifdef _KERNEL
93
94/*
95 * Random Source is a source of entropy that can provide
96 * specified or approximate amount of entropy immediately
97 * upon request.
98 */
99struct random_source {
100	const char				*rs_ident;
101	enum random_entropy_source		 rs_source;
102	random_source_read_t			*rs_read;
103};
104
105#if !defined(RANDOM_DUMMY)
106struct random_sources {
107	LIST_ENTRY(random_sources)		 rrs_entries;
108	struct random_source			*rrs_source;
109};
110#endif /* !defined(RANDOM_DUMMY) */
111
112void random_source_register(struct random_source *);
113void random_source_deregister(struct random_source *);
114
115void random_sources_feed(void);
116
117#endif /* _KERNEL */
118
119void randomdev_unblock(void);
120
121#endif /* SYS_DEV_RANDOM_RANDOMDEV_H_INCLUDED */
122