xref: /freebsd/sys/dev/random/randomdev.h (revision f3d2512db6ec23985b10fbcbe0b3bd34ea2574df)
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 */
39 SYSCTL_DECL(_kern_random);
40 
41 #define	RANDOM_CHECK_UINT(name, min, max)				\
42 static int								\
43 random_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 
56 MALLOC_DECLARE(M_ENTROPY);
57 
58 #endif /* _KERNEL */
59 
60 struct harvest_event;
61 
62 typedef void random_alg_init_t(void *);
63 typedef void random_alg_deinit_t(void *);
64 typedef void random_alg_pre_read_t(void);
65 typedef void random_alg_read_t(uint8_t *, u_int);
66 typedef bool random_alg_seeded_t(void);
67 typedef void random_alg_reseed_t(void);
68 typedef void random_alg_eventprocessor_t(struct harvest_event *);
69 
70 typedef u_int random_source_read_t(void *, u_int);
71 
72 /*
73  * Random Algorithm is a processor of randomness for the kernel
74  * and for userland.
75  */
76 struct random_algorithm {
77 	const char			*ra_ident;
78 	u_int				 ra_poolcount;
79 	void				(*ra_init_alg)(void *);
80 	void				(*ra_deinit_alg)(void *);
81 	random_alg_pre_read_t		*ra_pre_read;
82 	random_alg_read_t		*ra_read;
83 	random_alg_seeded_t		*ra_seeded;
84 	random_alg_eventprocessor_t	*ra_event_processor;
85 };
86 
87 extern struct random_algorithm random_alg_context, *p_random_alg_context;
88 
89 #ifdef _KERNEL
90 
91 /*
92  * Random Source is a source of entropy that can provide
93  * specified or approximate amount of entropy immediately
94  * upon request.
95  */
96 struct random_source {
97 	const char			*rs_ident;
98 	enum random_entropy_source	 rs_source;
99 	random_source_read_t		*rs_read;
100 };
101 
102 struct random_sources {
103 	LIST_ENTRY(random_sources)	 rrs_entries;
104 	struct random_source		*rrs_source;
105 };
106 
107 LIST_HEAD(sources_head, random_sources);
108 extern struct sources_head source_list;
109 
110 void random_source_register(struct random_source *);
111 void random_source_deregister(struct random_source *);
112 
113 #if defined(RANDOM_LOADABLE)
114 extern struct sx randomdev_config_lock;
115 #define	RANDOM_CONFIG_INIT_LOCK(x)	sx_init(&randomdev_config_lock, "configuration change lock")
116 #define	RANDOM_CONFIG_X_LOCK(x)		sx_xlock(&randomdev_config_lock)
117 #define	RANDOM_CONFIG_X_UNLOCK(x)	sx_xunlock(&randomdev_config_lock)
118 #define	RANDOM_CONFIG_S_LOCK(x)		sx_slock(&randomdev_config_lock)
119 #define	RANDOM_CONFIG_S_UNLOCK(x)	sx_sunlock(&randomdev_config_lock)
120 #define	RANDOM_CONFIG_DEINIT_LOCK(x)	sx_destroy(&randomdev_config_lock)
121 void random_infra_init(int (*)(struct uio *, bool), void (*)(void *, u_int),
122     bool (*)(void));
123 void random_infra_uninit(void);
124 #endif
125 
126 #endif /* _KERNEL */
127 
128 void randomdev_unblock(void);
129 
130 #endif /* SYS_DEV_RANDOM_RANDOMDEV_H_INCLUDED */
131