1 /*- 2 * Copyright (c) 2013-2015, 2017 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 27 #ifndef SYS_DEV_RANDOM_RANDOM_HARVESTQ_H_INCLUDED 28 #define SYS_DEV_RANDOM_RANDOM_HARVESTQ_H_INCLUDED 29 30 #include <sys/types.h> 31 #include <machine/cpu.h> 32 33 #define HARVESTSIZE 2 /* Max length in words of each harvested entropy unit */ 34 35 /* These are used to queue harvested packets of entropy. The entropy 36 * buffer size is pretty arbitrary. 37 */ 38 struct harvest_event { 39 uint32_t he_somecounter; /* fast counter for clock jitter */ 40 uint32_t he_entropy[HARVESTSIZE];/* some harvested entropy */ 41 uint8_t he_size; /* harvested entropy byte count */ 42 uint8_t he_destination; /* destination pool of this entropy */ 43 uint8_t he_source; /* origin of the entropy */ 44 }; 45 46 static inline uint32_t 47 random_get_cyclecount(void) 48 { 49 return ((uint32_t)get_cyclecount()); 50 } 51 52 bool random_harvest_healthtest(const struct harvest_event *event); 53 54 #endif /* SYS_DEV_RANDOM_RANDOM_HARVESTQ_H_INCLUDED */ 55