freebsd-src/sys/dev/random/randomdev_soft.h
David E. O'Brien 5711939b63 * Add random_adaptors.[ch] which is basically a store of random_adaptor's.
random_adaptor is basically an adapter that plugs in to random(4).
  random_adaptor can only be plugged in to random(4) very early in bootup.
  Unplugging random_adaptor from random(4) is not supported, and is probably a
  bad idea anyway, due to potential loss of entropy pools.
  We currently have 3 random_adaptors:
  + yarrow
  + rdrand (ivy.c)
  + nehemeiah

* Remove platform dependent logic from probe.c, and move it into
  corresponding registration routines of each random_adaptor provider.
  probe.c doesn't do anything other than picking a specific random_adaptor
  from a list of registered ones.

* If the kernel doesn't have any random_adaptor adapters present then the
  creation of /dev/random is postponed until next random_adaptor is kldload'ed.

* Fix randomdev_soft.c to refer to its own random_adaptor, instead of a
  system wide one.

Submitted by: arthurmesh@gmail.com, obrien
Obtained from: Juniper Networks
Reviewed by: so (des)
2013-08-09 15:31:50 +00:00

95 lines
3.4 KiB
C

/*-
* Copyright (c) 2000-2004 Mark R V Murray
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer
* in this position and unchanged.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
/* This header contains only those definitions that are global
* and harvester-specific for the entropy processor
*/
/* #define ENTROPYSOURCE nn entropy sources (actually classes)
* This is properly defined in
* an enum in sys/random.h
*/
/* Cryptographic block size in bits */
#define BLOCKSIZE 256
/* The ring size _MUST_ be a power of 2 */
#define HARVEST_RING_SIZE 1024 /* harvest ring buffer size */
#define HARVEST_RING_MASK (HARVEST_RING_SIZE - 1)
#define HARVESTSIZE 16 /* max size of each harvested entropy unit */
MALLOC_DECLARE(M_ENTROPY);
/* These are used to queue harvested packets of entropy. The entropy
* buffer size is pretty arbitrary.
*/
struct harvest {
uintmax_t somecounter; /* fast counter for clock jitter */
u_char entropy[HARVESTSIZE]; /* the harvested entropy */
u_int size, bits, frac; /* stats about the entropy */
enum esource source; /* stats about the entropy */
STAILQ_ENTRY(harvest) next; /* next item on the list */
};
void random_yarrow_init(void);
void random_yarrow_deinit(void);
int random_yarrow_read(void *, int);
void random_yarrow_write(void *, int);
void random_yarrow_init_harvester(void (*)(u_int64_t, const void *, u_int,
u_int, u_int, enum esource), int (*)(void *, int));
void random_yarrow_deinit_harvester(void);
void random_set_wakeup_exit(void *);
void random_process_event(struct harvest *event);
void random_yarrow_reseed(void);
void random_yarrow_unblock(void);
void random_yarrow_init_alg(struct sysctl_ctx_list *);
void random_yarrow_deinit_alg(void);
extern struct random_adaptor random_yarrow;
extern struct mtx random_reseed_mtx;
/* If this was c++, this would be a template */
#define RANDOM_CHECK_UINT(name, min, max) \
static int \
random_check_uint_##name(SYSCTL_HANDLER_ARGS) \
{ \
if (oidp->oid_arg1 != NULL) { \
if (*(u_int *)(oidp->oid_arg1) <= (min)) \
*(u_int *)(oidp->oid_arg1) = (min); \
else if (*(u_int *)(oidp->oid_arg1) > (max)) \
*(u_int *)(oidp->oid_arg1) = (max); \
} \
return sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, \
req); \
}