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Decouple yarrow from random(4) device.

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* Make Yarrow an optional kernel component -- enabled by "YARROW_RNG" option.
  The files sha2.c, hash.c, randomdev_soft.c and yarrow.c comprise yarrow.

* random(4) device doesn't really depend on rijndael-*.  Yarrow, however, does.

* 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: obrien
This commit is contained in:
David E. O'Brien 2013-07-29 20:26:27 +00:00
parent 23b5c8fe3d
commit 99ff83da74
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=253779
81 changed files with 316 additions and 138 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
UPDATING
View File

@ -31,6 +31,19 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 10.x IS SLOW:
disable the most expensive debugging functionality run
"ln -s 'abort:false,junk:false' /etc/malloc.conf".)
20130729:
random(4) and actual RNG implementations (aka, adaptors) have been
further decoupled. If you are running a custom kernel, you may
need to explicitly enable at least one RNG adaptor in your kernel
config. For example, to use Yarrow, add "options YARROW_RNG" to
your kernel config. For hardware backed RNGs, use either
"RDRAND_RNG" or "PADLOCK_RNG" options.
If you use random.ko via 'random_load="YES"' in /boot/loader.conf
instead of "device random", you will need to change that to
'yarrow_rng_load="YES"', 'rdrand_rng_load="YES"', or
'padlock_rng_load="YES"'. random.ko will be loaded automatically
as a dependency module.
20130726:
Behavior of devfs rules path matching has been changed.
Pattern is now always matched against fully qualified devfs

14
share/man/man4/random.4
View File

@ -23,7 +23,7 @@
.\"
.\" $FreeBSD$
.\"
.Dd September 7, 2012
.Dd July 29, 2013
.Dt RANDOM 4
.Os
.Sh NAME
@ -43,6 +43,13 @@ The device will probe for
certain hardware entropy sources,
and use these in preference to the fallback,
which is a generator implemented in software.
If the kernel environment MIB's
.Va hw.nehemiah_rng_enable
or
.Va hw.ivy_rng_enable
are set to
.Dq Li 0 ,
the associated hardware entropy source will be ignored.
.Pp
If the device is using
the software generator,
@ -74,6 +81,7 @@ device, use the command line:
.Pp
which results in something like:
.Bd -literal -offset indent
kern.random.adaptors: yarrow
kern.random.sys.seeded: 1
kern.random.sys.harvest.ethernet: 1
kern.random.sys.harvest.point_to_point: 1
@ -89,7 +97,9 @@ kern.random.yarrow.slowoverthresh: 2
(These would not be seen if a
hardware generator is present.)
.Pp
All settings are read/write.
Other than
.Dl kern.random.adaptors
all settings are read/write.
.Pp
The
.Va kern.random.sys.seeded

1
sys/amd64/conf/GENERIC
View File

@ -295,6 +295,7 @@ device loop # Network loopback
device random # Entropy device
options PADLOCK_RNG # VIA Padlock RNG
options RDRAND_RNG # Intel Bull Mountain RNG
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
device vlan # 802.1Q VLAN support
device tun # Packet tunnel.

1
sys/arm/conf/AC100
View File

@ -61,6 +61,7 @@ options MUTEX_DEBUG
# Pseudo devices
device random
options YARROW_RNG # Yarrow software RNG
device pty
device loop
device md

1
sys/arm/conf/ARMADAXP
View File

@ -61,6 +61,7 @@ options KDB_TRACE
# Pseudo devices
device random
options YARROW_RNG # Yarrow software RNG
device pty
device loop
device md

1
sys/arm/conf/ARNDALE
View File

@ -88,6 +88,7 @@ options ROOTDEVNAME=\"ufs:/dev/da0\"
device loop
device random
options YARROW_RNG # Yarrow software RNG
device pty
device md
device gpio

1
sys/arm/conf/ATMEL
View File

@ -134,6 +134,7 @@ device geom_map # GEOM partition mapping
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
device vlan # 802.1Q VLAN support
device tun # Packet tunnel.

1
sys/arm/conf/AVILA
View File

@ -107,6 +107,7 @@ device if_bridge
device md
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
# Wireless NIC cards
device wlan # 802.11 support

1
sys/arm/conf/BEAGLEBONE
View File

@ -90,6 +90,7 @@ device pty
device snp
device md
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
# I2C support
device iicbus

1
sys/arm/conf/BWCT
View File

@ -68,6 +68,7 @@ options NO_FFS_SNAPSHOT
options NO_SWAPPING
device loop
device random
options YARROW_RNG # Yarrow software RNG
device ether
device vlan
device uart

1
sys/arm/conf/CAMBRIA
View File

@ -110,6 +110,7 @@ device if_bridge
device md
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
# Wireless NIC cards
device wlan # 802.11 support

1
sys/arm/conf/CNS11XXNAS
View File

@ -102,6 +102,7 @@ device loop
device md
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
#options ARM_USE_SMALL_ALLOC

1
sys/arm/conf/CRB
View File

@ -105,6 +105,7 @@ options DDB #Enable the kernel debugger
options XSCALE_CACHE_READ_WRITE_ALLOCATE
device md
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device iopwdog
options ARM_USE_SMALL_ALLOC

2
sys/arm/conf/CUBIEBOARD
View File

@ -92,6 +92,7 @@ device pty
device snp
device md
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
# I2C support
#device iicbus
@ -130,4 +131,3 @@ device miibus
options FDT
options FDT_DTB_STATIC
makeoptions FDT_DTS_FILE=cubieboard.dts

1
sys/arm/conf/DB-78XXX
View File

@ -55,6 +55,7 @@ device pci
device loop
device md
device random
options YARROW_RNG # Yarrow software RNG
# Serial ports
device uart

1
sys/arm/conf/DB-88F5XXX
View File

@ -54,6 +54,7 @@ device pci
device md
device loop
device random
options YARROW_RNG # Yarrow software RNG
# Serial ports
device uart

1
sys/arm/conf/DB-88F6XXX
View File

@ -55,6 +55,7 @@ device pci
device loop
device md
device random
options YARROW_RNG # Yarrow software RNG
# Serial ports
device uart

1
sys/arm/conf/DOCKSTAR
View File

@ -46,6 +46,7 @@ options KDB
# Pseudo devices
device md
device random
options YARROW_RNG # Yarrow software RNG
device loop
# Serial ports

1
sys/arm/conf/DREAMPLUG-1001
View File

@ -62,6 +62,7 @@ device loop #Network loopback
device md #Memory/malloc disk
device pty #BSD-style compatibility pseudo ttys
device random #Entropy device
options YARROW_RNG # Yarrow software RNG
device tun #Packet tunnel.
device ether #Required for all ethernet devices
device vlan #802.1Q VLAN support

1
sys/arm/conf/EA3250
View File

@ -54,6 +54,7 @@ device loop
device md
device pty
device random
options YARROW_RNG # Yarrow software RNG
# Serial ports
device uart

1
sys/arm/conf/EB9200
View File

@ -60,6 +60,7 @@ options SX_NOINLINE
options NO_FFS_SNAPSHOT
options NO_SWAPPING
device random
options YARROW_RNG # Yarrow software RNG
device loop
device ether
device uart

1
sys/arm/conf/EFIKA_MX
View File

@ -96,6 +96,7 @@ device bpf # Berkeley packet filter
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
#device vlan # 802.1Q VLAN support
#device tun # Packet tunnel.

1
sys/arm/conf/EP80219
View File

@ -101,6 +101,7 @@ options DDB #Enable the kernel debugger
options XSCALE_CACHE_READ_WRITE_ALLOCATE
device md
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
options ARM_USE_SMALL_ALLOC
# Floppy drives

1
sys/arm/conf/ETHERNUT5
View File

@ -126,6 +126,7 @@ device geom_map # GEOM partition mapping
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
#device vlan # 802.1Q VLAN support
#device tun # Packet tunnel.

1
sys/arm/conf/GUMSTIX
View File

@ -88,3 +88,4 @@ options DDB #Enable the kernel debugger
device md
device random # Entropy device
options YARROW_RNG # Yarrow software RNG

1
sys/arm/conf/HL200
View File

@ -65,6 +65,7 @@ options RWLOCK_NOINLINE
options NO_FFS_SNAPSHOT
options NO_SWAPPING
device random
options YARROW_RNG # Yarrow software RNG
device loop
device ether
device uart

2
sys/arm/conf/HL201
View File

@ -67,6 +67,7 @@ options RWLOCK_NOINLINE
options NO_FFS_SNAPSHOT
options NO_SWAPPING
device random
options YARROW_RNG # Yarrow software RNG
device loop
device ether
device uart
@ -129,4 +130,3 @@ device pass # Passthrough device (direct SCSI access)
#device wlan_tkip # 802.11 TKIP support
#device wlan_amrr # AMRR transmit rate control algorithm
options ROOTDEVNAME=\"ufs:da0s1a\"

1
sys/arm/conf/IQ31244
View File

@ -106,6 +106,7 @@ options DDB #Enable the kernel debugger
options XSCALE_CACHE_READ_WRITE_ALLOCATE
device md
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
options ARM_USE_SMALL_ALLOC
# Floppy drives

1
sys/arm/conf/KB920X
View File

@ -66,6 +66,7 @@ options SX_NOINLINE
options NO_FFS_SNAPSHOT
options NO_SWAPPING
device random
options YARROW_RNG # Yarrow software RNG
device loop
device ether
device uart

2
sys/arm/conf/LN2410SBC
View File

@ -62,6 +62,7 @@ options SX_NOINLINE
options NO_FFS_SNAPSHOT
options NO_SWAPPING
device random
options YARROW_RNG # Yarrow software RNG
device loop
device ether
@ -83,4 +84,3 @@ device ohci
device umass
device scbus # SCSI bus (required for da)
device da # Direct Access (disks)

1
sys/arm/conf/NSLU
View File

@ -105,6 +105,7 @@ device loop
device md
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
#options ARM_USE_SMALL_ALLOC

1
sys/arm/conf/PANDABOARD
View File

@ -110,6 +110,7 @@ device md
#options MD_ROOT_SIZE=7560
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
# USB support
device usb

1
sys/arm/conf/QILA9G20
View File

@ -77,6 +77,7 @@ options NO_SWAPPING
#options DIAGNOSTIC
device random
options YARROW_RNG # Yarrow software RNG
device loop
device bpf
device ether

1
sys/arm/conf/RPI-B
View File

@ -86,6 +86,7 @@ options INVARIANT_SUPPORT #Extra sanity checks of internal structures, required
device md
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
# USB support
device usb

1
sys/arm/conf/SAM9260EK
View File

@ -134,6 +134,7 @@ device mmcsd # MMC/SD memory card
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
#device vlan # 802.1Q VLAN support
#device tun # Packet tunnel.

1
sys/arm/conf/SAM9G20EK
View File

@ -76,6 +76,7 @@ options NO_SWAPPING
#options DIAGNOSTIC
device random
options YARROW_RNG # Yarrow software RNG
device loop
device bpf
device ether

2
sys/arm/conf/SAM9X25EK
View File

@ -77,6 +77,7 @@ options NO_SWAPPING
#options DIAGNOSTIC
device random
options YARROW_RNG # Yarrow software RNG
device pty
device loop
device bpf
@ -150,4 +151,3 @@ device miibus
#device wlan_ccmp # 802.11 CCMP support
#device wlan_tkip # 802.11 TKIP support
#device wlan_amrr # AMRR transmit rate control algorithm

1
sys/arm/conf/SHEEVAPLUG
View File

@ -45,6 +45,7 @@ options KDB
# Pseudo devices
device random
options YARROW_RNG # Yarrow software RNG
device loop
# Serial ports

1
sys/arm/conf/SN9G45
View File

@ -76,6 +76,7 @@ options NO_SWAPPING
#options DIAGNOSTIC
device random
options YARROW_RNG # Yarrow software RNG
device loop
device bpf
device ether

1
sys/arm/conf/TS7800
View File

@ -48,6 +48,7 @@ device pci
device md
device loop
device random
options YARROW_RNG # Yarrow software RNG
# Serial ports
device uart

1
sys/arm/conf/VERSATILEPB
View File

@ -94,6 +94,7 @@ options INVARIANT_SUPPORT #Extra sanity checks of internal structures, required
device md
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
# Flattened Device Tree
options FDT

1
sys/arm/conf/ZEDBOARD
View File

@ -66,6 +66,7 @@ options KDB
device loop
device random
options YARROW_RNG # Yarrow software RNG
device ether
device if_cgem # Zynq-7000 gig ethernet device
device mii

3
sys/conf/NOTES
View File

@ -1132,6 +1132,9 @@ options VFS_AIO
# Cryptographically secure random number generator; /dev/random
device random
# Yarrow software RNG adapter for random
options YARROW_RNG
# The system memory devices; /dev/mem, /dev/kmem
device mem

11
sys/conf/files
View File

@ -540,8 +540,8 @@ crypto/des/des_ecb.c optional crypto | ipsec | netsmb
crypto/des/des_setkey.c optional crypto | ipsec | netsmb
crypto/rc4/rc4.c optional netgraph_mppc_encryption | kgssapi
crypto/rijndael/rijndael-alg-fst.c optional crypto | geom_bde | \
ipsec | random | wlan_ccmp
crypto/rijndael/rijndael-api-fst.c optional geom_bde | random
ipsec | yarrow_rng | wlan_ccmp
crypto/rijndael/rijndael-api-fst.c optional geom_bde | yarrow_rng
crypto/rijndael/rijndael-api.c optional crypto | ipsec | wlan_ccmp
crypto/sha1.c optional carp | crypto | ipsec | \
netgraph_mppc_encryption | sctp
@ -2030,11 +2030,12 @@ rt2860.fw optional rt2860fw | ralfw \
no-obj no-implicit-rule \
clean "rt2860.fw"
dev/random/harvest.c standard
dev/random/hash.c optional random
dev/random/hash.c optional yarrow_rng
dev/random/probe.c optional random
dev/random/random_adaptors.c standard
dev/random/randomdev.c optional random
dev/random/randomdev_soft.c optional random
dev/random/yarrow.c optional random
dev/random/randomdev_soft.c optional yarrow_rng
dev/random/yarrow.c optional yarrow_rng
dev/rc/rc.c optional rc
dev/re/if_re.c optional re
dev/rndtest/rndtest.c optional rndtest

3
sys/conf/options
View File

@ -905,3 +905,6 @@ RACCT opt_global.h
# Resource Limits
RCTL opt_global.h
# Software random number generators for random(4)
YARROW_RNG opt_dontuse.h

41
sys/dev/random/ivy.c
View File

@ -28,16 +28,19 @@
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_cpu.h"
#ifdef RDRAND_RNG
#include <sys/param.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/selinfo.h>
#include <sys/systm.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>
#include <dev/random/random_adaptors.h>
#include <dev/random/randomdev.h>
#define RETRY_COUNT 10
@ -46,7 +49,7 @@ static void random_ivy_init(void);
static void random_ivy_deinit(void);
static int random_ivy_read(void *, int);
struct random_systat random_ivy = {
struct random_adaptor random_ivy = {
.ident = "Hardware, Intel IvyBridge+ RNG",
.init = random_ivy_init,
.deinit = random_ivy_deinit,
@ -114,4 +117,32 @@ random_ivy_read(void *buf, int c)
return (c - count);
}
static int
rdrand_modevent(module_t mod, int type, void *unused)
{
switch (type) {
case MOD_LOAD:
if (cpu_feature2 & CPUID2_RDRAND) {
random_adaptor_register("rdrand", &random_ivy);
EVENTHANDLER_INVOKE(random_adaptor_attach, &random_ivy);
return (0);
} else {
#ifndef KLD_MODULE
if (bootverbose)
#endif
printf(
"%s: RDRAND feature is not present on this CPU\n",
random_ivy.ident);
#ifdef KLD_MODULE
return (ENXIO);
#else
return (0);
#endif
}
}
return (EINVAL);
}
RANDOM_ADAPTOR_MODULE(random_rdrand, rdrand_modevent, 1);

40
sys/dev/random/nehemiah.c
View File

@ -28,19 +28,20 @@
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_cpu.h"
#ifdef PADLOCK_RNG
#include <sys/param.h>
#include <sys/time.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/module.h>
#include <sys/selinfo.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <machine/pcb.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>
#include <dev/random/random_adaptors.h>
#include <dev/random/randomdev.h>
#define RANDOM_BLOCK_SIZE 256
@ -50,7 +51,7 @@ static void random_nehemiah_init(void);
static void random_nehemiah_deinit(void);
static int random_nehemiah_read(void *, int);
struct random_systat random_nehemiah = {
struct random_adaptor random_nehemiah = {
.ident = "Hardware, VIA Nehemiah",
.init = random_nehemiah_init,
.deinit = random_nehemiah_deinit,
@ -208,4 +209,33 @@ random_nehemiah_read(void *buf, int c)
return (c);
}
static int
nehemiah_modevent(module_t mod, int type, void *unused)
{
switch (type) {
case MOD_LOAD:
if (via_feature_rng & VIA_HAS_RNG) {
random_adaptor_register("nehemiah", &random_nehemiah);
EVENTHANDLER_INVOKE(random_adaptor_attach,
&random_nehemiah);
return (0);
} else {
#ifndef KLD_MODULE
if (bootverbose)
#endif
printf(
"%s: VIA RNG feature is not present on this CPU\n",
random_nehemiah.ident);
#ifdef KLD_MODULE
return (ENXIO);
#else
return (0);
#endif
}
}
return (EINVAL);
}
RANDOM_ADAPTOR_MODULE(nehemiah, nehemiah_modevent, 1);

61
sys/dev/random/probe.c
View File

@ -28,66 +28,35 @@
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#if defined(__amd64__) || (defined(__i386__) && !defined(PC98))
#if defined(__amd64__) || defined(__i386__)
#include "opt_cpu.h"
#endif
#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/random.h>
#include <sys/selinfo.h>
#include <sys/sysctl.h>
#if defined(__amd64__) || (defined(__i386__) && !defined(PC98))
#include <machine/cpufunc.h>
#include <machine/cputypes.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>
#endif
#include <dev/random/random_adaptors.h>
#include <dev/random/randomdev.h>
#include <dev/random/randomdev_soft.h>
#if defined(__amd64__) || (defined(__i386__) && !defined(PC98))
#ifdef PADLOCK_RNG
extern struct random_systat random_nehemiah;
#endif
#ifdef RDRAND_RNG
extern struct random_systat random_ivy;
#endif
#endif
void
random_ident_hardware(struct random_systat **systat)
random_ident_hardware(struct random_adaptor **adaptor)
{
struct random_adaptor *tmp;
int enable;
/* Set default to software */
*systat = &random_yarrow;
/* Set default to software (yarrow) */
*adaptor = random_adaptor_get("yarrow");
/* Then go looking for hardware */
#if defined(__amd64__) || (defined(__i386__) && !defined(PC98))
#ifdef PADLOCK_RNG
if (via_feature_rng & VIA_HAS_RNG) {
int enable;
enable = 1;
TUNABLE_INT_FETCH("hw.nehemiah_rng_enable", &enable);
if (enable && (tmp = random_adaptor_get("nehemiah")))
*adaptor = tmp;
enable = 1;
TUNABLE_INT_FETCH("hw.nehemiah_rng_enable", &enable);
if (enable)
*systat = &random_nehemiah;
}
#endif
#ifdef RDRAND_RNG
if (cpu_feature2 & CPUID2_RDRAND) {
int enable;
enable = 1;
TUNABLE_INT_FETCH("hw.ivy_rng_enable", &enable);
if (enable)
*systat = &random_ivy;
}
#endif
#endif
enable = 1;
TUNABLE_INT_FETCH("hw.ivy_rng_enable", &enable);
if (enable && (tmp = random_adaptor_get("rdrand")))
*adaptor = tmp;
}

76
sys/dev/random/randomdev.c
View File

@ -70,12 +70,15 @@ static struct cdevsw random_cdevsw = {
.d_name = "random",
};
struct random_systat *random_systat;
static struct random_adaptor *random_adaptor;
static eventhandler_tag attach_tag;
static int random_inited;
/* For use with make_dev(9)/destroy_dev(9). */
static struct cdev *random_dev;
/* Used to fake out unused random calls in random_systat */
/* Used to fake out unused random calls in random_adaptor */
void
random_null_func(void)
{
@ -88,8 +91,8 @@ random_close(struct cdev *dev __unused, int flags, int fmt __unused,
{
if ((flags & FWRITE) && (priv_check(td, PRIV_RANDOM_RESEED) == 0)
&& (securelevel_gt(td->td_ucred, 0) == 0)) {
(*random_systat->reseed)();
random_systat->seeded = 1;
(*random_adaptor->reseed)();
random_adaptor->seeded = 1;
arc4rand(NULL, 0, 1); /* Reseed arc4random as well. */
}
@ -104,8 +107,8 @@ random_read(struct cdev *dev __unused, struct uio *uio, int flag)
void *random_buf;
/* Blocking logic */
if (!random_systat->seeded)
error = (*random_systat->block)(flag);
if (!random_adaptor->seeded)
error = (*random_adaptor->block)(flag);
/* The actual read */
if (!error) {
@ -114,7 +117,7 @@ random_read(struct cdev *dev __unused, struct uio *uio, int flag)
while (uio->uio_resid > 0 && !error) {
c = MIN(uio->uio_resid, PAGE_SIZE);
c = (*random_systat->read)(random_buf, c);
c = (*random_adaptor->read)(random_buf, c);
error = uiomove(random_buf, c, uio);
}
@ -139,7 +142,7 @@ random_write(struct cdev *dev __unused, struct uio *uio, int flag __unused)
error = uiomove(random_buf, c, uio);
if (error)
break;
(*random_systat->write)(random_buf, c);
(*random_adaptor->write)(random_buf, c);
}
free(random_buf, M_TEMP);
@ -172,14 +175,37 @@ random_poll(struct cdev *dev __unused, int events, struct thread *td)
int revents = 0;
if (events & (POLLIN | POLLRDNORM)) {
if (random_systat->seeded)
if (random_adaptor->seeded)
revents = events & (POLLIN | POLLRDNORM);
else
revents = (*random_systat->poll) (events,td);
revents = (*random_adaptor->poll) (events,td);
}
return (revents);
}
static void
random_initialize(void *p, struct random_adaptor *s)
{
if (random_inited) {
printf("random: <%s> already initialized\n",
random_adaptor->ident);
return;
}
random_adaptor = s;
(s->init)();
printf("random: <%s> initialized\n", s->ident);
random_dev = make_dev_credf(MAKEDEV_ETERNAL_KLD, &random_cdevsw,
RANDOM_MINOR, NULL, UID_ROOT, GID_WHEEL, 0666, "random");
make_dev_alias(random_dev, "urandom"); /* XXX Deprecated */
/* mark random(4) as initialized, to avoid being called again */
random_inited = 1;
}
/* ARGSUSED */
static int
random_modevent(module_t mod __unused, int type, void *data __unused)
@ -188,23 +214,29 @@ random_modevent(module_t mod __unused, int type, void *data __unused)
switch (type) {
case MOD_LOAD:
random_ident_hardware(&random_systat);
(*random_systat->init)();
random_ident_hardware(&random_adaptor);
if (bootverbose)
printf("random: <entropy source, %s>\n",
random_systat->ident);
random_dev = make_dev_credf(MAKEDEV_ETERNAL_KLD, &random_cdevsw,
RANDOM_MINOR, NULL, UID_ROOT, GID_WHEEL, 0666, "random");
make_dev_alias(random_dev, "urandom"); /* XXX Deprecated */
if (random_adaptor == NULL) {
printf(
"random: No random adaptor attached, postponing initialization\n");
attach_tag = EVENTHANDLER_REGISTER(random_adaptor_attach,
random_initialize, NULL, EVENTHANDLER_PRI_ANY);
} else {
random_initialize(NULL, random_adaptor);
}
break;
case MOD_UNLOAD:
(*random_systat->deinit)();
destroy_dev(random_dev);
if (random_adaptor != NULL) {
(*random_adaptor->deinit)();
destroy_dev(random_dev);
}
/* Unregister the event handler */
if (attach_tag != NULL) {
EVENTHANDLER_DEREGISTER(random_adaptor_attach,
attach_tag);
}
break;

6
sys/dev/random/randomdev.h
View File

@ -38,7 +38,7 @@ typedef void random_write_func_t(void *, int);
typedef int random_poll_func_t(int, struct thread *);
typedef void random_reseed_func_t(void);
struct random_systat {
struct random_adaptor {
struct selinfo rsel;
const char *ident;
int seeded;
@ -51,7 +51,5 @@ struct random_systat {
random_reseed_func_t *reseed;
};
extern struct random_systat *random_systat;
extern void random_ident_hardware(struct random_systat **);
extern void random_ident_hardware(struct random_adaptor **);
extern void random_null_func(void);

62
sys/dev/random/randomdev_soft.c
View File

@ -38,6 +38,7 @@ __FBSDID("$FreeBSD$");
#include <sys/kthread.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/poll.h>
#include <sys/proc.h>
@ -50,6 +51,7 @@ __FBSDID("$FreeBSD$");
#include <machine/bus.h>
#include <machine/cpu.h>
#include <dev/random/random_adaptors.h>
#include <dev/random/randomdev.h>
#include <dev/random/randomdev_soft.h>
@ -63,7 +65,7 @@ static int random_yarrow_poll(int event,struct thread *td);
static int random_yarrow_block(int flag);
static void random_yarrow_flush_reseed(void);
struct random_systat random_yarrow = {
struct random_adaptor random_yarrow = {
.ident = "Software, Yarrow",
.init = random_yarrow_init,
.deinit = random_yarrow_deinit,
@ -103,7 +105,7 @@ static int random_kthread_control = 0;
static struct proc *random_kthread_proc;
/* List for the dynamic sysctls */
struct sysctl_ctx_list random_clist;
static struct sysctl_ctx_list random_clist;
/* ARGSUSED */
static int
@ -120,25 +122,20 @@ random_yarrow_init(void)
{
int error, i;
struct harvest *np;
struct sysctl_oid *random_o, *random_sys_o, *random_sys_harvest_o;
struct sysctl_oid *random_sys_o, *random_sys_harvest_o;
enum esource e;
random_o = SYSCTL_ADD_NODE(&random_clist,
SYSCTL_STATIC_CHILDREN(_kern),
OID_AUTO, "random", CTLFLAG_RW, 0,
"Software Random Number Generator");
random_yarrow_init_alg(&random_clist, random_o);
random_yarrow_init_alg(&random_clist);
random_sys_o = SYSCTL_ADD_NODE(&random_clist,
SYSCTL_CHILDREN(random_o),
SYSCTL_STATIC_CHILDREN(_kern_random),
OID_AUTO, "sys", CTLFLAG_RW, 0,
"Entropy Device Parameters");
SYSCTL_ADD_PROC(&random_clist,
SYSCTL_CHILDREN(random_sys_o),
OID_AUTO, "seeded", CTLTYPE_INT | CTLFLAG_RW,
&random_systat->seeded, 1, random_check_boolean, "I",
&random_yarrow.seeded, 1, random_check_boolean, "I",
"Seeded State");
random_sys_harvest_o = SYSCTL_ADD_NODE(&random_clist,
@ -362,10 +359,10 @@ random_yarrow_write(void *buf, int count)
void
random_yarrow_unblock(void)
{
if (!random_systat->seeded) {
random_systat->seeded = 1;
selwakeuppri(&random_systat->rsel, PUSER);
wakeup(random_systat);
if (!random_yarrow.seeded) {
random_yarrow.seeded = 1;
selwakeuppri(&random_yarrow.rsel, PUSER);
wakeup(&random_yarrow);
}
(void)atomic_cmpset_int(&arc4rand_iniseed_state, ARC4_ENTR_NONE,
ARC4_ENTR_HAVE);
@ -377,10 +374,10 @@ random_yarrow_poll(int events, struct thread *td)
int revents = 0;
mtx_lock(&random_reseed_mtx);
if (random_systat->seeded)
if (random_yarrow.seeded)
revents = events & (POLLIN | POLLRDNORM);
else
selrecord(td, &random_systat->rsel);
selrecord(td, &random_yarrow.rsel);
mtx_unlock(&random_reseed_mtx);
return revents;
@ -394,12 +391,12 @@ random_yarrow_block(int flag)
mtx_lock(&random_reseed_mtx);
/* Blocking logic */
while (!random_systat->seeded && !error) {
while (!random_yarrow.seeded && !error) {
if (flag & O_NONBLOCK)
error = EWOULDBLOCK;
else {
printf("Entropy device is blocking.\n");
error = msleep(random_systat,
error = msleep(&random_yarrow,
&random_reseed_mtx,
PUSER | PCATCH, "block", 0);
}
@ -420,3 +417,30 @@ random_yarrow_flush_reseed(void)
random_yarrow_reseed();
}
static int
yarrow_modevent(module_t mod, int type, void *unused)
{
switch (type) {
case MOD_LOAD:
random_adaptor_register("yarrow", &random_yarrow);
/*
* For statically built kernels that contain both random.ko and
* *_rng.ko, this event handler will do nothing, since
* random.ko is loaded after *_rng.ko's, and hence hasn't yet
* registered for this event.
*
* In case where both random.ko and *_rng.ko are built as
* modules, random.ko is loaded prior to *_rng.ko's (by
* dependency). This event handler is there to delay creation
* of /dev/{u,}random and attachment of this *_rng.ko.
*/
EVENTHANDLER_INVOKE(random_adaptor_attach, &random_yarrow);
return (0);
}
return (EINVAL);
}
RANDOM_ADAPTOR_MODULE(yarrow, yarrow_modevent, 1);

4
sys/dev/random/randomdev_soft.h
View File

@ -72,10 +72,10 @@ 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 *, struct sysctl_oid *);
void random_yarrow_init_alg(struct sysctl_ctx_list *);
void random_yarrow_deinit_alg(void);
extern struct random_systat random_yarrow;
extern struct random_adaptor random_yarrow;
extern struct mtx random_reseed_mtx;
/* If this was c++, this would be a template */

5
sys/dev/random/yarrow.c
View File

@ -41,6 +41,7 @@ __FBSDID("$FreeBSD$");
#include <crypto/sha2/sha2.h>
#include <dev/random/hash.h>
#include <dev/random/random_adaptors.h>
#include <dev/random/randomdev_soft.h>
#include <dev/random/yarrow.h>
@ -101,7 +102,7 @@ random_process_event(struct harvest *event)
}
void
random_yarrow_init_alg(struct sysctl_ctx_list *clist, struct sysctl_oid *in_o)
random_yarrow_init_alg(struct sysctl_ctx_list *clist)
{
int i;
struct sysctl_oid *random_yarrow_o;
@ -110,7 +111,7 @@ random_yarrow_init_alg(struct sysctl_ctx_list *clist, struct sysctl_oid *in_o)
* have a very good clue about what they do!
*/
random_yarrow_o = SYSCTL_ADD_NODE(clist,
SYSCTL_CHILDREN(in_o),
SYSCTL_STATIC_CHILDREN(_kern_random),
OID_AUTO, "yarrow", CTLFLAG_RW, 0,
"Yarrow Parameters");

1
sys/i386/conf/GENERIC
View File

@ -309,6 +309,7 @@ device loop # Network loopback
device random # Entropy device
options PADLOCK_RNG # VIA Padlock RNG
options RDRAND_RNG # Intel Bull Mountain RNG
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
device vlan # 802.1Q VLAN support
device tun # Packet tunnel.

1
sys/i386/conf/XBOX
View File

@ -62,6 +62,7 @@ device pass # Passthrough device (direct ATA/SCSI access)
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
#device tun # Packet tunnel.
#device md # Memory "disks"

2
sys/i386/conf/XEN
View File

@ -76,6 +76,7 @@ device pci
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
device tun # Packet tunnel.
device md # Memory "disks"
@ -90,4 +91,3 @@ options AH_SUPPORT_AR5416
# Be aware of the administrative consequences of enabling this!
# Note that 'bpf' is required for DHCP.
device bpf # Berkeley packet filter

1
sys/ia64/conf/GENERIC
View File

@ -198,6 +198,7 @@ device loop # Network loopback
device md # Memory "disks"
device puc # Multi I/O cards and multi-channel UARTs
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device tun # Packet tunnel.
device uart # Serial port (UART)
device vlan # 802.1Q VLAN support

3
sys/mips/conf/AR71XX_BASE
View File

@ -24,7 +24,7 @@ makeoptions DEBUG=-g #Build kernel with gdb(1) debug symbols
# Build these as modules so small platform builds will have the
# modules already built.
makeoptions MODULES_OVERRIDE="random gpio ar71xx if_gif if_gre if_bridge bridgestp usb wlan wlan_xauth wlan_acl wlan_wep wlan_tkip wlan_ccmp wlan_rssadapt wlan_amrr ath ath_pci"
makeoptions MODULES_OVERRIDE="random yarrow_rng gpio ar71xx if_gif if_gre if_bridge bridgestp usb wlan wlan_xauth wlan_acl wlan_wep wlan_tkip wlan_ccmp wlan_rssadapt wlan_amrr ath ath_pci"
options DDB
options KDB
@ -115,6 +115,7 @@ device ether
device md
device bpf
device random
options YARROW_RNG # Yarrow software RNG
device if_bridge
device gif # ip[46] in ip[46] tunneling protocol
device gre # generic encapsulation - only for IPv4 in IPv4 though atm

2
sys/mips/conf/AR724X_BASE
View File

@ -25,7 +25,7 @@ makeoptions DEBUG=-g #Build kernel with gdb(1) debug symbols
# Build these as modules so small platform builds will have the
# modules already built.
makeoptions MODULES_OVERRIDE="random gpio ar71xx if_gif if_gre if_bridge bridgestp usb wlan wlan_xauth wlan_acl wlan_wep wlan_tkip wlan_ccmp wlan_rssadapt wlan_amrr ath ath_pci hwpmc cam"
makeoptions MODULES_OVERRIDE="random yarrow_rng gpio ar71xx if_gif if_gre if_bridge bridgestp usb wlan wlan_xauth wlan_acl wlan_wep wlan_tkip wlan_ccmp wlan_rssadapt wlan_amrr ath ath_pci hwpmc cam"
options DDB
options KDB

3
sys/mips/conf/AR91XX_BASE
View File

@ -20,7 +20,7 @@ files "../atheros/files.ar71xx"
hints "AR91XX_BASE.hints"
makeoptions DEBUG=-g #Build kernel with gdb(1) debug symbols
makeoptions MODULES_OVERRIDE="random gpio ar71xx if_gif if_gre if_bridge bridgestp usb wlan wlan_xauth wlan_acl wlan_wep wlan_tkip wlan_ccmp wlan_rssadapt wlan_amrr ath ath_ahb hwpmc"
makeoptions MODULES_OVERRIDE="random yarrow_rng gpio ar71xx if_gif if_gre if_bridge bridgestp usb wlan wlan_xauth wlan_acl wlan_wep wlan_tkip wlan_ccmp wlan_rssadapt wlan_amrr ath ath_ahb hwpmc"
options DDB
options KDB
@ -113,6 +113,7 @@ device ether
device md
device bpf
device random
options YARROW_RNG # Yarrow software RNG
device if_bridge
device gpio
device gpioled

3
sys/mips/conf/AR933X_BASE
View File

@ -20,7 +20,7 @@ files "../atheros/files.ar71xx"
hints "AR933X_BASE.hints"
makeoptions DEBUG=-g #Build kernel with gdb(1) debug symbols
# makeoptions MODULES_OVERRIDE="random gpio ar71xx if_gif if_gre if_bridge bridgestp usb wlan wlan_xauth wlan_acl wlan_wep wlan_tkip wlan_ccmp wlan_rssadapt wlan_amrr ath ath_ahb hwpmc"
# makeoptions MODULES_OVERRIDE="random yarrow_rng gpio ar71xx if_gif if_gre if_bridge bridgestp usb wlan wlan_xauth wlan_acl wlan_wep wlan_tkip wlan_ccmp wlan_rssadapt wlan_amrr ath ath_ahb hwpmc"
makeoptions MODULES_OVERRIDE=""
options DDB
@ -119,6 +119,7 @@ device ether
device md
device bpf
device random
options YARROW_RNG # Yarrow software RNG
device if_bridge
device gpio
device gpioled

1
sys/mips/conf/BERI_TEMPLATE
View File

@ -55,4 +55,5 @@ device md
device ether
device loop
device random
options YARROW_RNG # Yarrow software RNG
device snp

1
sys/mips/conf/DIR-825
View File

@ -20,6 +20,7 @@ hints "DIR-825.hints"
# Since the kernel image must fit inside 1024KiB, we have to build almost
# everything as modules.
nodevice random
nooptions YARROW_RNG
nodevice gpio
nodevice gpioled
nodevice gif

1
sys/mips/conf/GXEMUL
View File

@ -51,6 +51,7 @@ device gxemul_ether
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
device tun # Packet tunnel.
device md # Memory "disks"

1
sys/mips/conf/OCTEON1
View File

@ -256,6 +256,7 @@ device wi # WaveLAN/Intersil/Symbol 802.11 wireless NICs.
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
device vlan # 802.1Q VLAN support
device tun # Packet tunnel.

2
sys/mips/conf/PB92
View File

@ -22,7 +22,7 @@ options AR71XX_ENV_UBOOT
# who already are using it without modifying the default flash layout)
# we need to cut down on a lot of things.
makeoptions MODULES_OVERRIDE="ath ath_pci ath_ahb bridgestp if_bridge if_gif if_gre random wlan wlan_acl wlan_amrr wlan_ccmp wlan_rssadapt wlan_tkip wlan_wep wlan_xauth usb ar71xx"
makeoptions MODULES_OVERRIDE="ath ath_pci ath_ahb bridgestp if_bridge if_gif if_gre random yarrow_rng wlan wlan_acl wlan_amrr wlan_ccmp wlan_rssadapt wlan_tkip wlan_wep wlan_xauth usb ar71xx"
hints "PB92.hints"
include "../atheros/std.ar71xx"

3
sys/mips/conf/RT305X
View File

@ -24,7 +24,7 @@ makeoptions MIPS_LITTLE_ENDIAN=defined
makeoptions KERNLOADADDR=0x80001000
# Don't build any modules yet.
makeoptions MODULES_OVERRIDE="wlan_xauth wlan_wep wlan_tkip wlan_acl wlan_amrr wlan_ccmp wlan_rssadapt random if_bridge bridgestp msdosfs md ipfw dummynet libalias geom/geom_label ufs usb/uplcom usb/u3g usb/umodem usb/umass usb/ucom cam zlib"
makeoptions MODULES_OVERRIDE="wlan_xauth wlan_wep wlan_tkip wlan_acl wlan_amrr wlan_ccmp wlan_rssadapt random yarrow_rng if_bridge bridgestp msdosfs md ipfw dummynet libalias geom/geom_label ufs usb/uplcom usb/u3g usb/umodem usb/umass usb/ucom cam zlib"
makeoptions RT3052F
include "../rt305x/std.rt305x"
@ -90,6 +90,7 @@ options MROUTING # Multicast routing
options IPFIREWALL_DEFAULT_TO_ACCEPT
device random
options YARROW_RNG # Yarrow software RNG
device loop
# RT3050F, RT3052F have only pseudo PHYs, so mii not required
device rt

1
sys/mips/conf/XLR64
View File

@ -84,6 +84,7 @@ device uart
# Pseudo
device loop
device random
options YARROW_RNG # Yarrow software RNG
device md
device bpf

1
sys/mips/conf/XLRN32
View File

@ -85,6 +85,7 @@ device uart
# Pseudo
device loop
device random
options YARROW_RNG # Yarrow software RNG
device md
device bpf

1
sys/mips/conf/std.SWARM
View File

@ -42,6 +42,7 @@ device loop
device ether
device md
device random
options YARROW_RNG # Yarrow software RNG
options USB_DEBUG
device usb

1
sys/mips/conf/std.XLP
View File

@ -65,6 +65,7 @@ makeoptions FDT_DTS_FILE=xlp-basic.dts
# Pseudo
device loop
device random
options YARROW_RNG # Yarrow software RNG
device md
device bpf

5
sys/modules/Makefile
View File

@ -254,6 +254,7 @@ SUBDIR= \
${_opensolaris} \
oce \
${_padlock} \
${_padlock_rng} \
patm \
${_pccard} \
${_pcfclock} \
@ -280,6 +281,7 @@ SUBDIR= \
${_random} \
rc4 \
${_rdma} \
${_rdrand_rng} \
re \
reiserfs \
rl \
@ -364,11 +366,14 @@ SUBDIR= \
${_x86bios} \
${_xe} \
xl \
yarrow_rng \
${_zfs} \
zlib \
.if ${MACHINE_CPUARCH} == "i386" || ${MACHINE_CPUARCH} == "amd64"
_filemon= filemon
_padlock_rng= padlock_rng
_rdrand_rng= rdrand_rng
.endif
.if ${MACHINE_CPUARCH} != "powerpc" && ${MACHINE_CPUARCH} != "arm" && \

12
sys/modules/random/Makefile
View File

@ -1,19 +1,9 @@
# $FreeBSD$
.PATH: ${.CURDIR}/../../dev/random
.PATH: ${.CURDIR}/../../crypto/rijndael
.PATH: ${.CURDIR}/../../crypto/sha2
KMOD= random
SRCS= randomdev.c probe.c
.if ${MACHINE} == "amd64" || ${MACHINE} == "i386"
SRCS+= nehemiah.c
SRCS+= ivy.c
.endif
SRCS+= randomdev_soft.c yarrow.c hash.c
SRCS+= rijndael-alg-fst.c rijndael-api-fst.c sha2.c
SRCS+= bus_if.h device_if.h vnode_if.h opt_cpu.h
CFLAGS+= -I${.CURDIR}/../..
SRCS+= bus_if.h device_if.h opt_cpu.h
.include <bsd.kmod.mk>

1
sys/pc98/conf/GENERIC
View File

@ -217,6 +217,7 @@ options AH_SUPPORT_AR5416 # enable AR5416 tx/rx descriptors
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
device vlan # 802.1Q VLAN support
device tun # Packet tunnel.

1
sys/powerpc/conf/GENERIC
View File

@ -144,6 +144,7 @@ device fxp # Intel EtherExpress PRO/100B (82557, 82558)
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
device vlan # 802.1Q VLAN support
device tun # Packet tunnel.

1
sys/powerpc/conf/GENERIC64
View File

@ -141,6 +141,7 @@ device fxp # Intel EtherExpress PRO/100B (82557, 82558)
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
device vlan # 802.1Q VLAN support
device tun # Packet tunnel.

1
sys/powerpc/conf/MPC85XX
View File

@ -76,6 +76,7 @@ device pass
device pci
device quicc
device random
options YARROW_RNG # Yarrow software RNG
#device rl
device scbus
device scc

1
sys/powerpc/conf/WII
View File

@ -72,6 +72,7 @@ makeoptions SC_DFLT_FONT=cp437
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
device vlan # 802.1Q VLAN support
device tun # Packet tunnel.

1
sys/sparc64/conf/GENERIC
View File

@ -215,6 +215,7 @@ device ath_rate_sample # SampleRate tx rate control for ath
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
options YARROW_RNG # Yarrow software RNG
device ether # Ethernet support
device vlan # 802.1Q VLAN support
device tun # Packet tunnel.

12
tools/tools/sysdoc/sysdoc.sh
View File

@ -88,7 +88,7 @@ EOF
# tunables in our tunables.mdoc file and generate
# the final 'inner circle' of our manual page.
markup_create() {
sort < _names | \
sort -u < _names | \
xargs -n 1 /bin/sh ./sysctl.sh \
> markup.file \
2> tunables.TODO
@ -238,9 +238,13 @@ if [ -z "$LOCATION" ] ;
&& for x in `find $LOCATION -name '*.kld'` \
$LOCATION/kernel; \
do nm $x | \
grep ' sysctl___' | uniq | \
sed 's/sysctl___//g' | sed 's/_/./g' | \
awk {'print $3'} > _names;
sed -n '/sysctl___/ {
's/[\.a-z_]*sysctl___//g'
's/_/./g'
p
}' | \
awk {'print $3'} | \
sort -u > _names;
done;
markup_create
page_create

7
tools/tools/sysdoc/tunables.mdoc
View File

@ -1092,6 +1092,13 @@ line programs.
kern.quantum
---
kern.random.adaptors
str
Displays registered PRNG adaptors (sources).
This is a read-only variable.
---
kern.random.sys.burst