2 * Copyright (c) 2011 Alex Hornung <alex@alexhornung.com>.
5 * Redistribution and use in source and binary forms, with or without
6 * 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 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in
13 * the documentation and/or other materials provided with the
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
19 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
20 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
22 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
24 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/kernel.h>
32 #include <sys/module.h>
33 #include <sys/malloc.h>
34 #include <sys/libkern.h>
35 #include <sys/random.h>
37 #include <dev/crypto/padlock/padlock.h>
39 static int random_count = 16;
42 padlock_rng(int *out, size_t count)
48 * eax: (output) RNG status word
49 * ecx: (input) rep. count
50 * edx: (input) quality factor (0-3)
51 * edi: (input) buffer for random data
57 ".byte 0x0f, 0xa7, 0xc0"
59 : "d" (2), "D" (out), "c" (count*sizeof(*out))
65 padlock_rng_harvest(void *arg)
67 struct padlock_softc *sc = arg;
69 int *arandomness; /* randomness aligned */
72 arandomness = PADLOCK_ALIGN(randomness);
73 padlock_rng(arandomness, random_count);
75 for (i = 0; i < random_count; i++)
76 add_true_randomness(arandomness[i]);
78 callout_reset(&sc->sc_rng_co, sc->sc_rng_ticks,
79 padlock_rng_harvest, sc);
83 padlock_rng_init(struct padlock_softc *sc)
86 sc->sc_rng_ticks = hz/100;
90 callout_init_mp(&sc->sc_rng_co);
91 callout_reset(&sc->sc_rng_co, sc->sc_rng_ticks,
92 padlock_rng_harvest, sc);
96 padlock_rng_uninit(struct padlock_softc *sc)
98 callout_stop(&sc->sc_rng_co);