1 /* $NetBSD: hyperentropy.c,v 1.2 2014/01/17 14:57:04 pooka Exp $ */ 2 3 /* 4 * Copyright (c) 2014 Antti Kantee. All Rights Reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 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 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 16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __KERNEL_RCSID(0, "$NetBSD: hyperentropy.c,v 1.2 2014/01/17 14:57:04 pooka Exp $"); 30 31 #include <sys/param.h> 32 #include <sys/kmem.h> 33 #include <sys/rnd.h> 34 35 #include <rump/rumpuser.h> 36 37 #include "rump_private.h" 38 39 static krndsource_t rndsrc; 40 41 #define MAXGET (RND_POOLBITS/NBBY) 42 static void 43 feedrandom(size_t bytes, void *arg) 44 { 45 uint8_t *rnddata; 46 size_t dsize; 47 48 rnddata = kmem_intr_alloc(MAXGET, KM_SLEEP); 49 if (rumpuser_getrandom(rnddata, MIN(MAXGET, bytes), 50 RUMPUSER_RANDOM_HARD|RUMPUSER_RANDOM_NOWAIT, &dsize) == 0) 51 rnd_add_data(&rndsrc, rnddata, dsize, NBBY*dsize); 52 kmem_intr_free(rnddata, MAXGET); 53 } 54 55 void 56 rump_hyperentropy_init(void) 57 { 58 59 if (rump_threads) { 60 rndsource_setcb(&rndsrc, feedrandom, &rndsrc); 61 rnd_attach_source(&rndsrc, "rump_hyperent", RND_TYPE_VM, 62 RND_FLAG_NO_ESTIMATE|RND_FLAG_HASCB); 63 } else { 64 /* without threads, just fill the pool */ 65 rnd_attach_source(&rndsrc, "rump_hyperent", RND_TYPE_VM, 66 RND_FLAG_NO_ESTIMATE); 67 feedrandom(RND_POOLBITS/NBBY, NULL); 68 } 69 } 70