1 | /* $NetBSD: rndsource.h,v 1.5 2016/02/17 00:43:43 riastradh Exp $ */ |
2 | |
3 | /*- |
4 | * Copyright (c) 1997 The NetBSD Foundation, Inc. |
5 | * All rights reserved. |
6 | * |
7 | * This code is derived from software contributed to The NetBSD Foundation |
8 | * by Michael Graff <explorer@flame.org>. This code uses ideas and |
9 | * algorithms from the Linux driver written by Ted Ts'o. |
10 | * |
11 | * Redistribution and use in source and binary forms, with or without |
12 | * modification, are permitted provided that the following conditions |
13 | * are met: |
14 | * 1. Redistributions of source code must retain the above copyright |
15 | * notice, this list of conditions and the following disclaimer. |
16 | * 2. Redistributions in binary form must reproduce the above copyright |
17 | * notice, this list of conditions and the following disclaimer in the |
18 | * documentation and/or other materials provided with the distribution. |
19 | * |
20 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
21 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
22 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
23 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
24 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
25 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
26 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
27 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
28 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
29 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
30 | * POSSIBILITY OF SUCH DAMAGE. |
31 | */ |
32 | |
33 | #ifndef _SYS_RNDSOURCE_H |
34 | #define _SYS_RNDSOURCE_H |
35 | |
36 | #ifndef _KERNEL /* XXX */ |
37 | #error <sys/rndsource.h> is meant for kernel consumers only. |
38 | #endif |
39 | |
40 | #include <sys/types.h> |
41 | #include <sys/null.h> |
42 | #include <sys/rndio.h> /* RND_TYPE_*, RND_FLAG_* */ |
43 | #include <sys/rngtest.h> |
44 | #include <sys/queue.h> |
45 | |
46 | typedef struct rnd_delta_estimator { |
47 | uint64_t x; |
48 | uint64_t dx; |
49 | uint64_t d2x; |
50 | uint64_t insamples; |
51 | uint64_t outbits; |
52 | } rnd_delta_t; |
53 | |
54 | typedef struct krndsource { |
55 | LIST_ENTRY(krndsource) list; /* the linked list */ |
56 | char name[16]; /* device name */ |
57 | rnd_delta_t time_delta; /* time delta estimator */ |
58 | rnd_delta_t value_delta; /* value delta estimator */ |
59 | uint32_t total; /* entropy from this source */ |
60 | uint32_t type; /* type */ |
61 | uint32_t flags; /* flags */ |
62 | void *state; /* state information */ |
63 | size_t test_cnt; /* how much test data accumulated? */ |
64 | void (*get)(size_t, void *); /* pool wants N bytes (badly) */ |
65 | void *getarg; /* argument to get-function */ |
66 | void (*enable)(struct krndsource *, bool); /* turn on/off */ |
67 | rngtest_t *test; /* test data for RNG type sources */ |
68 | unsigned refcnt; |
69 | } krndsource_t; |
70 | |
71 | static inline void |
72 | rndsource_setcb(struct krndsource *const rs, void (*const cb)(size_t, void *), |
73 | void *const arg) |
74 | { |
75 | rs->get = cb; |
76 | rs->getarg = arg; |
77 | } |
78 | |
79 | static inline void |
80 | rndsource_setenable(struct krndsource *const rs, void *const cb) |
81 | { |
82 | rs->enable = cb; |
83 | } |
84 | |
85 | #define RND_ENABLED(rp) \ |
86 | (((rp)->flags & RND_FLAG_NO_COLLECT) == 0) |
87 | |
88 | void _rnd_add_uint32(krndsource_t *, uint32_t); |
89 | void _rnd_add_uint64(krndsource_t *, uint64_t); |
90 | void rnd_add_data(krndsource_t *, const void *const, uint32_t, |
91 | uint32_t); |
92 | void rnd_add_data_sync(krndsource_t *, const void *, uint32_t, |
93 | uint32_t); |
94 | void rnd_attach_source(krndsource_t *, const char *, |
95 | uint32_t, uint32_t); |
96 | void rnd_detach_source(krndsource_t *); |
97 | |
98 | static inline void |
99 | rnd_add_uint32(krndsource_t *kr, uint32_t val) |
100 | { |
101 | if (__predict_true(kr)) { |
102 | if (RND_ENABLED(kr)) { |
103 | _rnd_add_uint32(kr, val); |
104 | } |
105 | } else { |
106 | rnd_add_data(NULL, &val, sizeof(val), 0); |
107 | } |
108 | } |
109 | |
110 | static inline void |
111 | rnd_add_uint64(krndsource_t *kr, uint64_t val) |
112 | { |
113 | if (__predict_true(kr)) { |
114 | if (RND_ENABLED(kr)) { |
115 | _rnd_add_uint64(kr, val); |
116 | } |
117 | } else { |
118 | rnd_add_data(NULL, &val, sizeof(val), 0); |
119 | } |
120 | } |
121 | |
122 | #endif /* _SYS_RNDSOURCE_H */ |
123 | |