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 * $FreeBSD$
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);
40SYSCTL_DECL(_kern_random_initial_seeding);
41
42#define	RANDOM_CHECK_UINT(name, min, max)				\
43static int								\
44random_check_uint_##name(SYSCTL_HANDLER_ARGS)				\
45{									\
46	if (oidp->oid_arg1 != NULL) {					\
47		if (*(u_int *)(oidp->oid_arg1) <= (min))		\
48			*(u_int *)(oidp->oid_arg1) = (min);		\
49		else if (*(u_int *)(oidp->oid_arg1) > (max))		\
50			*(u_int *)(oidp->oid_arg1) = (max);		\
51	}								\
52	return (sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2,	\
53		req));							\
54}
55#endif /* SYSCTL_DECL */
56
57MALLOC_DECLARE(M_ENTROPY);
58
59extern bool random_bypass_before_seeding;
60extern bool read_random_bypassed_before_seeding;
61extern bool arc4random_bypassed_before_seeding;
62extern bool random_bypass_disable_warnings;
63
64#endif /* _KERNEL */
65
66struct harvest_event;
67
68typedef void random_alg_pre_read_t(void);
69typedef void random_alg_read_t(uint8_t *, size_t);
70typedef bool random_alg_seeded_t(void);
71typedef void random_alg_eventprocessor_t(struct harvest_event *);
72
73typedef u_int random_source_read_t(void *, u_int);
74
75/*
76 * Random Algorithm is a processor of randomness for the kernel
77 * and for userland.
78 */
79struct random_algorithm {
80	const char			*ra_ident;
81	u_int				 ra_poolcount;
82	random_alg_pre_read_t		*ra_pre_read;
83	random_alg_read_t		*ra_read;
84	random_alg_seeded_t		*ra_seeded;
85	random_alg_eventprocessor_t	*ra_event_processor;
86};
87
88#if defined(RANDOM_LOADABLE)
89extern const struct random_algorithm *p_random_alg_context;
90#else
91extern const struct random_algorithm random_alg_context;
92#define	p_random_alg_context (&random_alg_context)
93#endif
94
95#ifdef _KERNEL
96
97/*
98 * Random Source is a source of entropy that can provide
99 * specified or approximate amount of entropy immediately
100 * upon request.
101 */
102struct random_source {
103	const char			*rs_ident;
104	enum random_entropy_source	 rs_source;
105	random_source_read_t		*rs_read;
106};
107
108void random_source_register(struct random_source *);
109void random_source_deregister(struct random_source *);
110
111#endif /* _KERNEL */
112
113void randomdev_unblock(void);
114
115#endif /* SYS_DEV_RANDOM_RANDOMDEV_H_INCLUDED */
116