968 lines
19 KiB
C
968 lines
19 KiB
C
/* $NetBSD: rnd.c,v 1.8 1997/10/19 11:43:05 explorer Exp $ */
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/*-
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* Copyright (c) 1997 The NetBSD Foundation, Inc.
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* All rights reserved.
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*
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* This code is derived from software contributed to The NetBSD Foundation
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* by Michael Graff <explorer@flame.org>. This code uses ideas and
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* algorithms from the Linux driver written by Ted Ts'o.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the NetBSD
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* Foundation, Inc. and its contributors.
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* 4. Neither the name of The NetBSD Foundation nor the names of its
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* contributors may be used to endorse or promote products derived
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* from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
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* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
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* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <sys/param.h>
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#include <sys/ioctl.h>
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#include <sys/fcntl.h>
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#include <sys/select.h>
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#include <sys/poll.h>
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#include <sys/malloc.h>
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#include <sys/md5.h>
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#include <sys/proc.h>
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#include <sys/kernel.h>
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#include <sys/conf.h>
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#include <sys/systm.h>
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#include <sys/rnd.h>
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#include <sys/vnode.h>
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#ifdef RND_DEBUG
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#define DPRINTF(l,x) if (rnd_debug & (l)) printf x
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int rnd_debug = 0;
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#else
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#define DPRINTF(l,x)
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#endif
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#define RND_DEBUG_WRITE 0x0001
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#define RND_DEBUG_READ 0x0002
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#define RND_DEBUG_IOCTL 0x0004
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#define RND_DEBUG_SNOOZE 0x0008
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/*
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* list devices attached
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*/
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/* #define RND_VERBOSE */
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/*
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* Use the extraction time as a somewhat-random source
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*/
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#ifndef RND_USE_EXTRACT_TIME
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#define RND_USE_EXTRACT_TIME 1
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#endif
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/*
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* The size of a temporary buffer, malloc()ed when needed, and used for
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* reading and writing data.
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*/
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#define RND_TEMP_BUFFER_SIZE 128
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/*
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* This is the minimum amount of random data we can have and be
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* considered "readable"
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*/
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#define RND_ENTROPY_THRESHOLD 64
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typedef struct _rnd_event_t {
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rndsource_t *source;
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u_int32_t val;
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u_int32_t timestamp;
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} rnd_event_t;
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typedef struct _rnd_eventq_t {
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u_int16_t count;
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u_int16_t head;
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u_int16_t tail;
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rnd_event_t events[RND_EVENTQSIZE];
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} rnd_eventq_t;
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/*
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* the event queue
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*/
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static rnd_eventq_t rnd_events;
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/*
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* our select/poll queue
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*/
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struct selinfo rnd_selq;
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/*
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* Set when there are readers blocking on data from us, we have a timeout
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* scheduled, etc.
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*/
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#define RND_READWAITING 0x00000001
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#define RND_TIMEOUTPEND 0x00000002
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u_int32_t rnd_status;
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/*
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* our random pool. This is defined here rather than using the general
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* purpose one defined in rndpool.c
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*/
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static rndpool_t rnd_pool;
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/*
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* This is used for devices that pass a NULL source pointer into the
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* rnd_add_*() functions. The user never sees this source, and cannot
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* modify it.
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*/
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static rndsource_t rnd_source_no_estimate = {
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{ 'U', 'n', 'k', 'n', 'o', 'w', 'n', 0, 0, 0, 0, 0, 0, 0, 0, 0 },
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0, 0, 0, 0,
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(RND_FLAG_NO_ESTIMATE | RND_TYPE_UNKNOWN)
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};
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/*
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* This source is used to easily "remove" queue entries when the source
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* which actually generated the events is going away.
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*/
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static rndsource_t rnd_source_no_collect = {
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{ 'U', 'n', 'k', 'n', 'o', 'w', 'n', 0, 0, 0, 0, 0, 0, 0, 0, 0 },
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0, 0, 0, 0,
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(RND_FLAG_NO_COLLECT | RND_FLAG_NO_ESTIMATE | RND_TYPE_UNKNOWN)
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};
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void rndattach __P((int));
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int rndopen __P((dev_t, int, int, struct proc *));
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int rndclose __P((dev_t, int, int, struct proc *));
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int rndread __P((dev_t, struct uio *, int));
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int rndwrite __P((dev_t, struct uio *, int));
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int rndioctl __P((dev_t, u_long, caddr_t, int, struct proc *));
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int rndpoll __P((dev_t, int, struct proc *));
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static inline void rnd_wakeup_readers(void);
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static inline u_int32_t rnd_estimate_entropy(rndsource_t *, u_int32_t);
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static inline u_int32_t rnd_timestamp(void);
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static void rnd_timeout(void *);
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/*
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* Generate a 32-bit timestamp. This should be more machine dependant,
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* using cycle counters and the like when possible.
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*/
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static inline u_int32_t
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rnd_timestamp()
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{
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struct timeval tv;
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u_int32_t t;
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microtime(&tv);
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t = tv.tv_sec * 1000000 + tv.tv_usec;
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return t;
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}
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/*
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* Check to see if there are readers waiting on us. If so, kick them.
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*/
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static inline void
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rnd_wakeup_readers()
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{
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/*
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* If we have added new bits, and now have enough to do something,
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* wake up sleeping readers.
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*/
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if (rndpool_get_entropy_count(&rnd_pool) > RND_ENTROPY_THRESHOLD) {
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if (rnd_status & RND_READWAITING) {
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DPRINTF(RND_DEBUG_SNOOZE,
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("waking up pending readers.\n"));
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rnd_status &= ~RND_READWAITING;
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wakeup(&rnd_status);
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}
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selwakeup(&rnd_selq);
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}
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}
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/*
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* Use the timing of the event to estimate the entropy gathered.
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* Note that right now we will return either one or two, depending on
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* if all the differentials (first, second, and third) are non-zero.
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*/
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static inline u_int32_t
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rnd_estimate_entropy(rs, t)
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rndsource_t *rs;
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u_int32_t t;
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{
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int32_t delta;
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int32_t delta2;
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int32_t delta3;
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/*
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* If the time counter has overflowed, calculate the real difference.
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* If it has not, it is simplier.
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*/
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if (t < rs->last_time)
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delta = UINT_MAX - rs->last_time + t;
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else
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delta = rs->last_time - t;
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if (delta < 0)
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delta = -delta;
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/*
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* Calculate the second and third order differentials
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*/
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delta2 = rs->last_delta - delta;
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if (delta2 < 0)
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delta2 = -delta2;
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delta3 = rs->last_delta2 - delta2;
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if (delta3 < 0)
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delta3 = -delta3;
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rs->last_time = t;
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rs->last_delta = delta;
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rs->last_delta2 = delta2;
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/*
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* If any delta is 0, we got no entropy. If all are non-zero, we
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* got one bit.
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*
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* XXX This is probably too conservative, but better than that than
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* too liberal.
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*/
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if (delta == 0 || delta2 == 0 || delta3 == 0)
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return 0;
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return 1;
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}
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static int rnd_ready;
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LIST_HEAD(, __rndsource_element) rnd_sources;
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/*
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* attach the random device, and initialize the global random pool
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* for our use.
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*/
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void
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rndattach(num)
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int num;
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{
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rnd_init();
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}
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int
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rndopen(dev, flags, ifmt, p)
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dev_t dev;
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int flags, ifmt;
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struct proc *p;
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{
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if (rnd_ready == 0)
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return (ENXIO);
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if (minor(dev) == RND_DEV_RANDOM || minor(dev) == RND_DEV_URANDOM)
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return 0;
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return (ENXIO);
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}
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int
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rndclose(dev, flags, ifmt, p)
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dev_t dev;
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int flags, ifmt;
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struct proc *p;
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{
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return (0);
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}
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int
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rndread(dev, uio, ioflag)
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dev_t dev;
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struct uio *uio;
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int ioflag;
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{
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int ret;
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u_int32_t nread;
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int n;
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int s;
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u_int8_t *buf;
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u_int32_t mode;
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u_int32_t entcnt;
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DPRINTF(RND_DEBUG_READ,
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("Random: Read of %d requested, flags 0x%08x\n",
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uio->uio_resid, ioflag));
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if (uio->uio_resid == 0)
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return (0);
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switch (minor(dev)) {
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case RND_DEV_RANDOM:
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mode = RND_EXTRACT_GOOD;
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break;
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case RND_DEV_URANDOM:
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mode = RND_EXTRACT_ANY;
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break;
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default:
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/* Can't happen, but this is cheap */
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return (ENXIO);
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}
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ret = 0;
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buf = malloc(RND_TEMP_BUFFER_SIZE, M_TEMP, M_WAITOK);
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while (uio->uio_resid > 0) {
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n = min(RND_TEMP_BUFFER_SIZE, uio->uio_resid);
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/*
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* Make certain there is data available. If there
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* is, do the I/O even if it is partial. If not,
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* sleep unless the user has requested non-blocking
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* I/O.
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*/
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for (;;) {
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/*
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* If not requesting strong randomness, we
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* can always read.
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*/
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if (mode == RND_EXTRACT_ANY)
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break;
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/*
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* How much entropy do we have? If it is enough for
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* one hash, we can read.
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*/
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s = splsoftclock();
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entcnt = rndpool_get_entropy_count(&rnd_pool);
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splx(s);
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if (entcnt >= RND_ENTROPY_THRESHOLD)
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break;
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/*
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* Data is not available.
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*/
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if (ioflag & IO_NDELAY) {
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ret = EWOULDBLOCK;
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goto out;
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}
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rnd_status |= RND_READWAITING;
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ret = tsleep(&rnd_status, PRIBIO|PCATCH,
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"rndread", 0);
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if (ret)
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goto out;
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}
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nread = rnd_extract_data(buf, n, mode);
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/*
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* copy (possibly partial) data to the user.
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* If an error occurs, or this is a partial
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* read, bail out.
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*/
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ret = uiomove((caddr_t)buf, nread, uio);
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if (ret != 0 || nread != n)
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goto out;
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}
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out:
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free(buf, M_TEMP);
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return (ret);
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}
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int
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rndwrite(dev, uio, ioflag)
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dev_t dev;
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struct uio *uio;
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int ioflag;
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{
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u_int8_t *buf;
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int ret;
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int n;
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int s;
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DPRINTF(RND_DEBUG_WRITE,
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("Random: Write of %d requested\n", uio->uio_resid));
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if (uio->uio_resid == 0)
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return (0);
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ret = 0;
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buf = malloc(RND_TEMP_BUFFER_SIZE, M_TEMP, M_WAITOK);
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while (uio->uio_resid > 0) {
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n = min(RND_TEMP_BUFFER_SIZE, uio->uio_resid);
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ret = uiomove((caddr_t)buf, n, uio);
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if (ret != 0)
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break;
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/*
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* Mix in the bytes.
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*/
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s = splsoftclock();
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rndpool_add_data(&rnd_pool, buf, n, 0);
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splx(s);
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DPRINTF(RND_DEBUG_WRITE, ("Random: Copied in %d bytes\n", n));
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}
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free(buf, M_TEMP);
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return (ret);
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}
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int
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rndioctl(dev, cmd, addr, flag, p)
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dev_t dev;
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u_long cmd;
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caddr_t addr;
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int flag;
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struct proc *p;
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{
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int ret;
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rndsource_element_t *rse;
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rndstat_t *rst;
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rndstat_name_t *rstnm;
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rndctl_t *rctl;
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rnddata_t *rnddata;
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u_int32_t count;
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u_int32_t start;
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int s;
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ret = 0;
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switch (cmd) {
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/*
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* Handled in upper layer really, but we have to return zero
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* for it to be accepted by the upper layer.
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*/
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case FIONBIO:
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case FIOASYNC:
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break;
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case RNDGETENTCNT:
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s = splsoftclock();
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*(u_int32_t *)addr = rndpool_get_entropy_count(&rnd_pool);
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splx(s);
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break;
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case RNDGETPOOL:
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if ((ret = suser(p->p_ucred, &p->p_acflag)) != 0)
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return (ret);
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s = splsoftclock();
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ret = copyout(rndpool_get_pool(&rnd_pool),
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addr, rndpool_get_poolsize());
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splx(s);
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break;
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case RNDADDTOENTCNT:
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if ((ret = suser(p->p_ucred, &p->p_acflag)) != 0)
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return (ret);
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s = splsoftclock();
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rndpool_increment_entropy_count(&rnd_pool, *(u_int32_t *)addr);
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rnd_wakeup_readers();
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splx(s);
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break;
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case RNDSETENTCNT:
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if ((ret = suser(p->p_ucred, &p->p_acflag)) != 0)
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return (ret);
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s = splsoftclock();
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rndpool_set_entropy_count(&rnd_pool, *(u_int32_t *)addr);
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rnd_wakeup_readers();
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splx(s);
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break;
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case RNDGETSRCNUM:
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if ((ret = suser(p->p_ucred, &p->p_acflag)) != 0)
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return (ret);
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rst = (rndstat_t *)addr;
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if (rst->count == 0)
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break;
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if (rst->count > RND_MAXSTATCOUNT)
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return (EINVAL);
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/*
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* find the starting source by running through the
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* list of sources.
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*/
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rse = rnd_sources.lh_first;
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start = rst->start;
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while (rse != NULL && start >= 1) {
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rse = rse->list.le_next;
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start--;
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}
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/*
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* Return up to as many structures as the user asked
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* for. If we run out of sources, a count of zero
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* will be returned, without an error.
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*/
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for (count = 0 ; count < rst->count && rse != NULL ; count++) {
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bcopy(&rse->data, &rst->source[count],
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sizeof(rndsource_t));
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rse = rse->list.le_next;
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}
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rst->count = count;
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break;
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case RNDGETSRCNAME:
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if ((ret = suser(p->p_ucred, &p->p_acflag)) != 0)
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return (ret);
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/*
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* scan through the list, trying to find the name
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*/
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rstnm = (rndstat_name_t *)addr;
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rse = rnd_sources.lh_first;
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while (rse != NULL) {
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if (strncmp(rse->data.name, rstnm->name, 16) == 0) {
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bcopy(&rse->data, &rstnm->source,
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sizeof(rndsource_t));
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return 0;
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}
|
|
rse = rse->list.le_next;
|
|
}
|
|
|
|
ret = ENOENT; /* name not found */
|
|
|
|
break;
|
|
|
|
case RNDCTL:
|
|
if ((ret = suser(p->p_ucred, &p->p_acflag)) != 0)
|
|
return (ret);
|
|
|
|
/*
|
|
* set flags to enable/disable entropy counting and/or
|
|
* collection
|
|
*/
|
|
rctl = (rndctl_t *)addr;
|
|
rse = rnd_sources.lh_first;
|
|
|
|
/*
|
|
* flags set apply to all sources of this type
|
|
*/
|
|
if (rctl->type != 0xff) {
|
|
while (rse != NULL) {
|
|
if ((rse->data.tyfl & 0xff) == rctl->type) {
|
|
rse->data.tyfl &= ~rctl->mask;
|
|
rse->data.tyfl |= (rctl->flags
|
|
& rctl->mask);
|
|
}
|
|
rse = rse->list.le_next;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* scan through the list, trying to find the name
|
|
*/
|
|
while (rse != NULL) {
|
|
if (strncmp(rse->data.name, rctl->name, 16) == 0) {
|
|
rse->data.tyfl &= ~rctl->mask;
|
|
rse->data.tyfl |= (rctl->flags & rctl->mask);
|
|
|
|
return 0;
|
|
}
|
|
rse = rse->list.le_next;
|
|
}
|
|
|
|
ret = ENOENT; /* name not found */
|
|
|
|
break;
|
|
|
|
case RNDADDDATA:
|
|
if ((ret = suser(p->p_ucred, &p->p_acflag)) != 0)
|
|
return (ret);
|
|
|
|
rnddata = (rnddata_t *)addr;
|
|
|
|
s = splsoftclock();
|
|
rndpool_add_data(&rnd_pool, rnddata->data, rnddata->len,
|
|
rnddata->entropy);
|
|
|
|
rnd_wakeup_readers();
|
|
splx(s);
|
|
|
|
break;
|
|
|
|
default:
|
|
return (EINVAL);
|
|
}
|
|
|
|
return (ret);
|
|
}
|
|
|
|
int
|
|
rndpoll(dev, events, p)
|
|
dev_t dev;
|
|
int events;
|
|
struct proc *p;
|
|
{
|
|
int revents;
|
|
int s;
|
|
u_int32_t entcnt;
|
|
|
|
/*
|
|
* we are always writable
|
|
*/
|
|
revents = events & (POLLOUT | POLLWRNORM);
|
|
|
|
/*
|
|
* Save some work if not checking for reads
|
|
*/
|
|
if ((events & (POLLIN | POLLRDNORM)) == 0)
|
|
return (revents);
|
|
|
|
/*
|
|
* If the minor device is not /dev/random, we are always readable.
|
|
*/
|
|
if (minor(dev) != RND_DEV_RANDOM) {
|
|
revents |= events & (POLLIN | POLLRDNORM);
|
|
return (revents);
|
|
}
|
|
|
|
/*
|
|
* make certain we have enough entropy to be readable
|
|
*/
|
|
s = splsoftclock();
|
|
entcnt = rndpool_get_entropy_count(&rnd_pool);
|
|
splx(s);
|
|
|
|
if (entcnt >= RND_ENTROPY_THRESHOLD)
|
|
revents |= events & (POLLIN | POLLRDNORM);
|
|
else
|
|
selrecord(p, &rnd_selq);
|
|
|
|
return (revents);
|
|
}
|
|
|
|
/*
|
|
* initialize the data for the random generator.
|
|
*/
|
|
void
|
|
rnd_init(void)
|
|
{
|
|
if (rnd_ready)
|
|
return;
|
|
|
|
LIST_INIT(&rnd_sources);
|
|
|
|
rnd_events.count = 0;
|
|
rnd_events.head = 0;
|
|
rnd_events.tail = 0;
|
|
|
|
rndpool_init(&rnd_pool);
|
|
|
|
rnd_ready = 1;
|
|
|
|
#ifdef RND_VERBOSE
|
|
printf("Random device ready\n");
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* add a source to our list of sources
|
|
*/
|
|
void
|
|
rnd_attach_source(rs, name, tyfl)
|
|
rndsource_element_t *rs;
|
|
char *name;
|
|
u_int32_t tyfl;
|
|
{
|
|
strcpy(rs->data.name, name);
|
|
|
|
/*
|
|
* force network devices to not collect any entropy by
|
|
* default
|
|
*/
|
|
if ((tyfl & 0x00ff) == RND_TYPE_NET)
|
|
tyfl |= RND_FLAG_NO_ESTIMATE;
|
|
|
|
rs->data.tyfl = tyfl;
|
|
|
|
LIST_INSERT_HEAD(&rnd_sources, rs, list);
|
|
|
|
#ifdef RND_VERBOSE
|
|
printf("%s: attached as an entropy source\n", rs->data.name);
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* remove a source from our list of sources
|
|
*/
|
|
void
|
|
rnd_detach_source(rs)
|
|
rndsource_element_t *rs;
|
|
{
|
|
u_int16_t count;
|
|
u_int16_t elem;
|
|
rnd_event_t *ev;
|
|
int s;
|
|
|
|
s = splhigh();
|
|
|
|
LIST_REMOVE(rs, list);
|
|
|
|
/*
|
|
* If there are events queued up, remove them from the event queue
|
|
*/
|
|
count = rnd_events.count;
|
|
elem = rnd_events.tail;
|
|
|
|
while (count--) {
|
|
ev = &rnd_events.events[elem++];
|
|
if (elem == RND_EVENTQSIZE)
|
|
elem = 0;
|
|
|
|
if (ev->source == &rs->data)
|
|
ev->source = &rnd_source_no_collect;
|
|
}
|
|
|
|
splx(s);
|
|
}
|
|
|
|
/*
|
|
* Add a value to the entropy pool. If rs is NULL no entropy estimation
|
|
* will be performed, otherwise it should point to the source-specific
|
|
* source structure.
|
|
*/
|
|
void
|
|
rnd_add_uint32(rs, val)
|
|
rndsource_element_t *rs;
|
|
u_int32_t val;
|
|
{
|
|
rndsource_t *rst;
|
|
int s;
|
|
|
|
s = splhigh();
|
|
|
|
if (rnd_events.count == RND_EVENTQSIZE) {
|
|
splx(s);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If the source is null, we don't want to estimate, but we will
|
|
* collect. Point to our internal source definition for this.
|
|
*/
|
|
if (rs == NULL)
|
|
rst = &rnd_source_no_estimate;
|
|
else
|
|
rst = &rs->data;
|
|
|
|
/*
|
|
* If we are not collecting any data at all, just return.
|
|
*/
|
|
if (rst->tyfl & RND_FLAG_NO_COLLECT) {
|
|
splx(s);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Otherwise, queue it up for later addition, and schedule a
|
|
* timeout to process it.
|
|
*/
|
|
rnd_events.events[rnd_events.head].source = rst;
|
|
rnd_events.events[rnd_events.head].val = val;
|
|
rnd_events.events[rnd_events.head].timestamp = rnd_timestamp();
|
|
rnd_events.head++;
|
|
if (rnd_events.head == RND_EVENTQSIZE)
|
|
rnd_events.head = 0;
|
|
rnd_events.count++;
|
|
|
|
if ((rnd_status & RND_TIMEOUTPEND) == 0) {
|
|
rnd_status |= RND_TIMEOUTPEND;
|
|
timeout(rnd_timeout, rst, 1);
|
|
}
|
|
|
|
splx(s);
|
|
}
|
|
|
|
static void
|
|
rnd_timeout(arg)
|
|
void *arg;
|
|
{
|
|
u_int32_t entropy;
|
|
rnd_event_t *ev;
|
|
int s;
|
|
u_int16_t count;
|
|
u_int16_t processed;
|
|
|
|
/*
|
|
* make certain nothing else can tweak our magic flag while we
|
|
* are doing so. This might allow multiple timeouts to be
|
|
* queued, but there should be at most one other.
|
|
*/
|
|
s = splhigh();
|
|
count = rnd_events.count;
|
|
rnd_status &= ~RND_TIMEOUTPEND;
|
|
splx(s);
|
|
|
|
if (count == 0)
|
|
return;
|
|
|
|
processed = 0;
|
|
|
|
s = splsoftclock();
|
|
while (count-- > 0) {
|
|
processed++;
|
|
|
|
/*
|
|
* we only modify the tail in this function, and always at
|
|
* splsoftclock.
|
|
*/
|
|
ev = &rnd_events.events[rnd_events.tail++];
|
|
if (rnd_events.tail == RND_EVENTQSIZE)
|
|
rnd_events.tail = 0;
|
|
|
|
/*
|
|
* We repeat this check here, since it is possible the source
|
|
* was disabled before we were called, but after the entry
|
|
* was queued.
|
|
*/
|
|
if ((ev->source->tyfl & RND_FLAG_NO_COLLECT) == 0) {
|
|
|
|
rndpool_add_uint32(&rnd_pool, ev->val, 0);
|
|
|
|
/*
|
|
* If we are not estimating entropy from this source,
|
|
* assume zero. We still add the timestamp, just
|
|
* don't bother calculating the estimation.
|
|
*/
|
|
if (ev->source->tyfl & RND_FLAG_NO_ESTIMATE)
|
|
entropy = 0;
|
|
else
|
|
entropy = rnd_estimate_entropy(ev->source,
|
|
ev->timestamp);
|
|
|
|
rndpool_add_uint32(&rnd_pool, ev->timestamp, entropy);
|
|
ev->source->total += entropy;
|
|
}
|
|
|
|
}
|
|
|
|
/*
|
|
* wake up any potential readers waiting.
|
|
*/
|
|
rnd_wakeup_readers();
|
|
|
|
splx(s);
|
|
|
|
s = splhigh();
|
|
rnd_events.count -= processed;
|
|
splx(s);
|
|
}
|
|
|
|
void
|
|
rnd_add_data(rs, p, len, entropy)
|
|
rndsource_element_t *rs;
|
|
void *p;
|
|
u_int32_t len;
|
|
u_int32_t entropy;
|
|
{
|
|
rndsource_t *rst;
|
|
int s;
|
|
u_int32_t t;
|
|
|
|
/*
|
|
* if the caller is trying to add more entropy than can possibly
|
|
* be in the buffer we are passed, ignore the whole thing.
|
|
*/
|
|
if (entropy > len * 8)
|
|
return;
|
|
|
|
s = splsoftclock();
|
|
|
|
/*
|
|
* If the source is null, we don't want to estimate, but we will
|
|
* collect.
|
|
*/
|
|
if (rs == NULL)
|
|
rst = &rnd_source_no_estimate;
|
|
else
|
|
rst = &rs->data;
|
|
|
|
/*
|
|
* If we are not collecting any data at all, just return.
|
|
*/
|
|
if (rst->tyfl & RND_FLAG_NO_COLLECT) {
|
|
splx(s);
|
|
return;
|
|
}
|
|
|
|
rndpool_add_data(&rnd_pool, p, len, entropy);
|
|
|
|
/*
|
|
* If we are not estimating timing entropy from this source, add
|
|
* the timestamp and assume zero entropy from timing info.
|
|
*/
|
|
t = rnd_timestamp();
|
|
if (rst->tyfl & RND_FLAG_NO_ESTIMATE)
|
|
entropy = 0;
|
|
else
|
|
entropy = rnd_estimate_entropy(rst, t);
|
|
|
|
rndpool_add_uint32(&rnd_pool, t, entropy);
|
|
rst->total += entropy;
|
|
|
|
rnd_wakeup_readers();
|
|
|
|
splx(s);
|
|
}
|
|
|
|
int
|
|
rnd_extract_data(p, len, flags)
|
|
void *p;
|
|
u_int32_t len;
|
|
u_int32_t flags;
|
|
{
|
|
int s;
|
|
int retval;
|
|
|
|
s = splsoftclock();
|
|
|
|
#if RND_USE_EXTRACT_TIME
|
|
rndpool_add_uint32(&rnd_pool, rnd_timestamp(), 0);
|
|
#endif
|
|
|
|
retval = rndpool_extract_data(&rnd_pool, p, len, flags);
|
|
|
|
splx(s);
|
|
|
|
return retval;
|
|
}
|
|
|