2 * Copyright (c) 2013-2014 Mark R V Murray
3 * Copyright (c) 2013 Arthur Mesh <arthurmesh@gmail.com>
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer
11 * in this position and unchanged.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 #ifndef SYS_DEV_RANDOM_RANDOM_HARVESTQ_H_INCLUDED
31 #define SYS_DEV_RANDOM_RANDOM_HARVESTQ_H_INCLUDED
33 #define HARVESTSIZE 16 /* max size of each harvested entropy unit */
35 /* These are used to queue harvested packets of entropy. The entropy
36 * buffer size is pretty arbitrary.
38 struct harvest_event {
39 uintmax_t he_somecounter; /* fast counter for clock jitter */
40 uint8_t he_entropy[HARVESTSIZE];/* some harvested entropy */
41 u_int he_size; /* harvested entropy byte count */
42 u_int he_bits; /* stats about the entropy */
43 u_int he_destination; /* destination pool of this entropy */
44 enum random_entropy_source he_source; /* origin of the entropy */
47 void random_harvestq_init(void (*)(struct harvest_event *), int);
48 void random_harvestq_deinit(void);
49 void random_harvestq_internal(const void *, u_int, u_int, enum random_entropy_source);
51 /* Pool count is used by anything needing to know how many entropy
52 * pools are currently being maintained.
53 * This is of use to (e.g.) the live source feed where we need to give
54 * all the pools a top-up.
56 extern int harvest_pool_count;
58 /* This is in randomdev.c as it needs to be permanently in the kernel */
59 void randomdev_set_wakeup_exit(void *);
61 /* Force all currently pending queue contents to clear, and kick the software processor */
62 void random_harvestq_flush(void);
64 /* Function called to process one harvested stochastic event */
65 extern void (*harvest_process_event)(struct harvest_event *);
67 /* Round-robin destination cache. */
68 extern u_int harvest_destination[ENTROPYSOURCE];
70 #endif /* SYS_DEV_RANDOM_RANDOM_HARVESTQ_H_INCLUDED */