Home | History | Annotate | Line # | Download | only in sys 
      1 /*	$NetBSD: rndsource.h,v 1.10 2023/08/04 07:38:53 riastradh Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2019 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Taylor R. Campbell.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #ifndef	_SYS_RNDSOURCE_H
     33 #define	_SYS_RNDSOURCE_H
     34 
     35 #ifndef _KERNEL			/* XXX */
     36 #error <sys/rndsource.h> is meant for kernel consumers only.
     37 #endif
     38 
     39 #include <sys/types.h>
     40 #include <sys/queue.h>
     41 #include <sys/rndio.h>
     42 #include <sys/rngtest.h>
     43 
     44 struct percpu;
     45 
     46 /*
     47  * struct rnd_delta_estimator
     48  *
     49  *	State for the time-delta entropy estimation model.
     50  */
     51 typedef struct rnd_delta_estimator {
     52 	uint64_t	x;
     53 	uint64_t	dx;
     54 	uint64_t	d2x;
     55 	uint64_t	insamples;
     56 	uint64_t	outbits;
     57 } rnd_delta_t;
     58 
     59 /*
     60  * struct krndsource
     61  *
     62  *	State for an entropy source.  To be allocated by a driver for a
     63  *	hardware entropy source, and treated as opaque.
     64  *
     65  *	There are a number of unused fields in order to preserve ABI
     66  *	compatibility with the old implementation.
     67  */
     68 struct krndsource {
     69 	LIST_ENTRY(krndsource) list;	/* the linked list */
     70 	char		name[16];	/* device name */
     71 	rnd_delta_t	time_delta;	/* time samples added while cold */
     72 	rnd_delta_t	value_delta;	/* value samples added whiel cold */
     73 	uint32_t	total;		/* number of bits added while cold */
     74 	uint32_t	type;		/* type, RND_TYPE_* */
     75 	uint32_t	flags;		/* flags, RND_FLAG_* */
     76 	void		*state;		/* percpu (struct rndsource_cpu *) */
     77 	size_t		test_cnt;	/* unused */
     78 	void		(*get)(size_t, void *);	/* pool wants N bytes (badly) */
     79 	void		*getarg;	/* argument to get-function */
     80 	void		(*enable)(struct krndsource *, bool); /* unused */
     81 	rngtest_t	*test;		/* unused */
     82 	unsigned	refcnt;		/* unused */
     83 };
     84 
     85 typedef struct krndsource krndsource_t;
     86 
     87 void	rndsource_setcb(struct krndsource *, void (*)(size_t, void *), void *);
     88 void	rnd_attach_source(struct krndsource *, const char *, uint32_t,
     89 	    uint32_t);
     90 void	rnd_detach_source(struct krndsource *);
     91 
     92 void	_rnd_add_uint32(struct krndsource *, uint32_t); /* legacy */
     93 void	_rnd_add_uint64(struct krndsource *, uint64_t); /* legacy */
     94 
     95 void	rnd_add_uint32(struct krndsource *, uint32_t);
     96 void	rnd_add_data(struct krndsource *, const void *, uint32_t, uint32_t);
     97 void	rnd_add_data_intr(struct krndsource *, const void *, uint32_t,
     98 	    uint32_t);
     99 void	rnd_add_data_sync(struct krndsource *, const void *, uint32_t,
    100 	    uint32_t);
    101 
    102 #endif	/* _SYS_RNDSOURCE_H */
    103