Hardware random number quality is measured from 0 (no entropy) to 1024
(perfect entropy). Allow hardware devices to assert the full range by
truncating the device-provided value at 1024 instead of 1023.
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
omap4_rng_init() checks bit 10 of the RNG_CONFIG_REG to determine whether
the RNG is already running before performing any initiliasation. This is not
the correct register to check, as the enable bit is in RNG_CONFIG_CONTROL.
Read from RNG_CONTROL_REG instead.
Signed-off-by: Andre Wolokita <Andre.Wolokita@analog.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In omap4_rng_init(), a check of bit 10 of the RNG_CONFIG_REG is done to determine
whether the RNG is running. This is suspicious firstly due to the use of
RNG_CONTROL_ENABLE_TRNG_MASK and secondly because the same mask is written to
RNG_CONTROL_REG after configuration of the FROs. Similar suspicious logic is
repeated in omap4_rng_cleanup() when RNG_CONTROL_REG masked with
RNG_CONTROL_ENABLE_TRNG_MASK is read, the same mask bit is cleared, and then
written to RNG_CONFIG_REG. Unless the TRNG is enabled with one bit in RNG_CONTROL
and disabled with another in RNG_CONFIG and these bits are mirrored in some way,
I believe that the TRNG is not really shutting off.
Apart from the strange logic, I have reason to suspect that the OMAP4 related
code in this driver is driving an Inside Secure IP hardware RNG and strongly
suspect that bit 10 of RNG_CONFIG_REG is one of the bits configuring the
sampling rate of the FROs. This option is by default set to 0 and is not being
set anywhere in omap-rng.c. Reading this bit during omap4_rng_init() will
always return 0. It will remain 0 because ~(value of TRNG_MASK in control) will
always be 0, because the TRNG is never shut off. This is of course presuming
that the OMAP4 features the Inside Secure IP.
I'm interested in knowing what the guys at TI think about this, as only they
can confirm or deny the detailed structure of these registers.
Signed-off-by: Andre Wolokita <Andre.Wolokita@analog.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This allows us to get rid of driver's remove() method.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Instead of using static hwrng structure that is reused between
binds/unbinds of the device let's embed it into driver's private
structure that we allocate. This way we are guaranteed not to stumble
onto something left from previous bind attempt.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This allows us to get rid of remove() method.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This allows us to get rid of remove() method.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This change converts bcm63xx-rng to use devm* API for managing all
resources, which allows us to dispense with the rest of error handling
path and remove() function. Also we combine hwern and driver-private
data into a single allocation, use clk_prepare_enable() instead
of "naked" clk_enable() and move clock enabling/disabling into hwrnd
inti(0 and cleanup() methods so the clock stays off until rng is
used.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This change adds devm_hwrng_register and devm_hwrng_unregister which
use can simplify error unwinding and unbinding code paths in device
drivers.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Instead of using #ifdefs let's mark suspend and resume methods as
__maybe_unused which will suppress compiler warnings about them being
unused and provide better compile coverage.
Because SIMPLE_DEV_PM_OPS() produces an empty omap_rng_pm structure in
case of !CONFIG_PM_SLEEP neither omap_rng_suspend nor omap_rng_resume
will end up being referenced and the change will not result in
increasing image size.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Even if bus is not hot-pluggable, the devices can be unbound from the
driver via sysfs, so we should not be using __exit annotations on
remove() methods. The only exception is drivers registered with
platform_driver_probe() which specifically disables sysfs bind/unbind
attributes.
Similarly probe() methods should not be marked __init unless
platform_driver_probe() is used.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Even if bus is not hot-pluggable, the devices can be unbound from the
driver via sysfs, so we should not be using __exit annotations on
remove() methods. The only exception is drivers registered with
platform_driver_probe() which specifically disables sysfs bind/unbind
attributes
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Even if bus is not hot-pluggable, the devices can be unbound from the
driver via sysfs, so we should not be using __exit annotations on
remove() methods. The only exception is drivers registered with
platform_driver_probe() which specifically disables sysfs bind/unbind
attributes.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This adds a driver for random number generator present on Broadcom
IPROC devices.
Reviewed-by: Ray Jui <rjui@broadcom.com>
Signed-off-by: Scott Branden <sbranden@broadcom.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Simplify the driver's probe function and error handling by using the
device managed allocators, while at it, drop the redundant "out of
memory" messages since these are already printed by the allocator.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
arch/mips/include/asm/mach-bcm63xx/bcm63xx_regs.h contains the register
definitions for this random number generator block, incorporate these
register definitions directly into the bcm63xx-rng driver so we do not
rely on this header to be provided.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
bcm_{readl,writel} macros expand to __raw_{readl,writel}, use these
directly such that we do not rely on the platform to provide these for
us. As a result, we no longer use bcm63xx_io.h, so remove that inclusion
too.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
makes code look a bit prettier.
Cc: linux-crypto@vger.kernel.org.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We always do hwrng_init in set_current_rng. In fact, our current
reference count system relies on this. So make this explicit by
moving hwrng_init into set_current_rng.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Rather than having callers of set_current_rng call drop_current_rng,
we can do it directly in set_current_rng.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently we only register the device when a valid RNG is added.
However the way it's done is buggy because we test whether there
is a current RNG to determine whether we need to register. As
the current RNG may be missing due to a reinitialisation error
this can lead to a reregistration of the device.
As the device already has to handle a NULL current RNG anyway,
let's just register the device always and remove the complexity.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The kref solution is still buggy because we were only focusing
on the register/unregister race. The same race affects the
setting of current_rng through sysfs.
This patch fixes it by using kref_get_unless_zero.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
There is no point in doing a manual completion for cleanup_done
when struct completion fits in perfectly.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The previous patch added one potential problem: we can still be
reading from a hwrng when it's unregistered. Add a wait for zero
in the hwrng_unregister path.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Amos Kong <akong@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
current_rng holds one reference, and we bump it every time we want
to do a read from it.
This means we only hold the rng_mutex to grab or drop a reference,
so accessing /sys/devices/virtual/misc/hw_random/rng_current doesn't
block on read of /dev/hwrng.
Using a kref is overkill (we're always under the rng_mutex), but
a standard pattern.
This also solves the problem that the hwrng_fillfn thread was
accessing current_rng without a lock, which could change (eg. to NULL)
underneath it.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Amos Kong <akong@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In next patch, we use reference counting for each struct hwrng,
changing reference count also needs to take mutex_lock. Before
releasing the lock, if we try to stop a kthread that waits to
take the lock to reduce the referencing count, deadlock will
occur.
Signed-off-by: Amos Kong <akong@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
There's currently a big lock around everything, and it means that we
can't query sysfs (eg /sys/devices/virtual/misc/hw_random/rng_current)
while the rng is reading. This is a real problem when the rng is slow,
or blocked (eg. virtio_rng with qemu's default /dev/random backend)
This doesn't help (it leaves the current lock untouched), just adds a
lock to protect the read function and the static buffers, in preparation
for transition.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Here's the set of driver core patches for 3.19-rc1.
They are dominated by the removal of the .owner field in platform
drivers. They touch a lot of files, but they are "simple" changes, just
removing a line in a structure.
Other than that, a few minor driver core and debugfs changes. There are
some ath9k patches coming in through this tree that have been acked by
the wireless maintainers as they relied on the debugfs changes.
Everything has been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
iEYEABECAAYFAlSOD20ACgkQMUfUDdst+ylLPACg2QrW1oHhdTMT9WI8jihlHVRM
53kAoLeteByQ3iVwWurwwseRPiWa8+MI
=OVRS
-----END PGP SIGNATURE-----
Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core update from Greg KH:
"Here's the set of driver core patches for 3.19-rc1.
They are dominated by the removal of the .owner field in platform
drivers. They touch a lot of files, but they are "simple" changes,
just removing a line in a structure.
Other than that, a few minor driver core and debugfs changes. There
are some ath9k patches coming in through this tree that have been
acked by the wireless maintainers as they relied on the debugfs
changes.
Everything has been in linux-next for a while"
* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
fs: debugfs: add forward declaration for struct device type
firmware class: Deletion of an unnecessary check before the function call "vunmap"
firmware loader: fix hung task warning dump
devcoredump: provide a one-way disable function
device: Add dev_<level>_once variants
ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
ath: use seq_file api for ath9k debugfs files
debugfs: add helper function to create device related seq_file
drivers/base: cacheinfo: remove noisy error boot message
Revert "core: platform: add warning if driver has no owner"
drivers: base: support cpu cache information interface to userspace via sysfs
drivers: base: add cpu_device_create to support per-cpu devices
topology: replace custom attribute macros with standard DEVICE_ATTR*
cpumask: factor out show_cpumap into separate helper function
driver core: Fix unbalanced device reference in drivers_probe
driver core: fix race with userland in device_add()
sysfs/kernfs: make read requests on pre-alloc files use the buffer.
sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
fs: sysfs: return EGBIG on write if offset is larger than file size
...
Pull crypto update from Herbert Xu:
- The crypto API is now documented :)
- Disallow arbitrary module loading through crypto API.
- Allow get request with empty driver name through crypto_user.
- Allow speed testing of arbitrary hash functions.
- Add caam support for ctr(aes), gcm(aes) and their derivatives.
- nx now supports concurrent hashing properly.
- Add sahara support for SHA1/256.
- Add ARM64 version of CRC32.
- Misc fixes.
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (77 commits)
crypto: tcrypt - Allow speed testing of arbitrary hash functions
crypto: af_alg - add user space interface for AEAD
crypto: qat - fix problem with coalescing enable logic
crypto: sahara - add support for SHA1/256
crypto: sahara - replace tasklets with kthread
crypto: sahara - add support for i.MX53
crypto: sahara - fix spinlock initialization
crypto: arm - replace memset by memzero_explicit
crypto: powerpc - replace memset by memzero_explicit
crypto: sha - replace memset by memzero_explicit
crypto: sparc - replace memset by memzero_explicit
crypto: algif_skcipher - initialize upon init request
crypto: algif_skcipher - removed unneeded code
crypto: algif_skcipher - Fixed blocking recvmsg
crypto: drbg - use memzero_explicit() for clearing sensitive data
crypto: drbg - use MODULE_ALIAS_CRYPTO
crypto: include crypto- module prefix in template
crypto: user - add MODULE_ALIAS
crypto: sha-mb - remove a bogus NULL check
crytpo: qat - Fix 64 bytes requests
...
CONFIG_PM is defined as the alternative of CONFIG_PM_RUNTIME and
CONFIG_PM_SLEEP, so it can be used instead of that.
Besides, after commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if
PM_SLEEP is selected) PM_RUNTIME is always set if PM is set, so
using the alternative isn't even necessary.
Use CONFIG_PM instead of it in drivers/char/hw_random/exynos-rng.c.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Add DT support.
Make the driver depend on CONFIG_OF as at91sam9g45 was the only SoC making
use of the TRNG block and this SoC is now fully migrated to DT.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Use clk_prepare_enable/_disable_unprepare instead of clk_enable/disable
to work properly with the CCF.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The add_early_randomness() function in drivers/char/hw_random/core.c passes
a 16-byte buffer to pseries_rng_data_read(). Unfortunately, plpar_hcall()
returns four 64-bit values and trashes 16 bytes on the stack.
This bug has been lying around for a long time. It got unveiled by:
commit d3cc799647
Author: Amit Shah <amit.shah@redhat.com>
Date: Thu Jul 10 15:42:34 2014 +0530
hwrng: fetch randomness only after device init
It may trig a oops while loading or unloading the pseries-rng module for both
PowerVM and PowerKVM guests.
This patch does two things:
- pass an intermediate well sized buffer to plpar_hcall(). This is acceptalbe
since we're not on a hot path.
- move to the new read API so that we know the return buffer size for sure.
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The buf is used to hold the list of hwrng devices registered.
The old code ensures we don't walk off the end of buf as we
fill it, but it's unnecessarily complicated and thus difficult
to maintain. Simplify it by using strlcat.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Reviewed-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
been sitting in MST's tree during my vacation. I changed a function name
and made one trivial change, then they spent two days in linux-next.
Thanks,
Rusty.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=JK6x
-----END PGP SIGNATURE-----
Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull virtio updates from Rusty Russell:
"One cc: stable commit, the rest are a series of minor cleanups which
have been sitting in MST's tree during my vacation. I changed a
function name and made one trivial change, then they spent two days in
linux-next"
* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (25 commits)
virtio-rng: refactor probe error handling
virtio_scsi: drop scan callback
virtio_balloon: enable VQs early on restore
virtio_scsi: fix race on device removal
virito_scsi: use freezable WQ for events
virtio_net: enable VQs early on restore
virtio_console: enable VQs early on restore
virtio_scsi: enable VQs early on restore
virtio_blk: enable VQs early on restore
virtio_scsi: move kick event out from virtscsi_init
virtio_net: fix use after free on allocation failure
9p/trans_virtio: enable VQs early
virtio_console: enable VQs early
virtio_blk: enable VQs early
virtio_net: enable VQs early
virtio: add API to enable VQs early
virtio_net: minor cleanup
virtio-net: drop config_mutex
virtio_net: drop config_enable
virtio-blk: drop config_mutex
...
Code like
vi->vq = NULL;
kfree(vi)
does not make sense.
Clean it up, use goto error labels for cleanup.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
as pr_* macros are more preffered over printk, so printk replaced with corresponding pr_* macros
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Before we really unregister the hwrng device, reading will get stuck if
the virtio device is reset. We should return error for reading when we
start to remove the device.
Signed-off-by: Amos Kong <akong@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When we try to hot-remove a busy virtio-rng device from QEMU monitor,
the device can't be hot-removed. Because virtio-rng driver hangs at
wait_for_completion_killable().
This patch exits the waiting by completing have_data completion before
unregistering, resets data_avail to avoid the hwrng core use wrong
buffer bytes.
Signed-off-by: Amos Kong <akong@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The khwrngd thread is started when a hwrng device of sufficient
quality is registered. The virtio-rng device is backed by the
hypervisor, and we trust the hypervisor to provide real entropy.
A malicious or badly-implemented hypervisor is a scenario that's
irrelevant -- such a setup is bound to cause all sorts of badness, and a
compromised hwrng is the least of the user's worries.
Given this, we might as well assume that the quality of randomness we
receive is perfectly trustworthy. Hence, we use 100% for the factor,
indicating maximum confidence in the source.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: H. Peter Anvin <hpa@linux.intel.com>
Reviewed-by: Amos Kong <akong@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
call, which is a superset of OpenBSD's getentropy(2) call, for use
with userspace crypto libraries such as LibreSSL. Also add the
ability to have a kernel thread to pull entropy from hardware rng
devices into /dev/random.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=wLqJ
-----END PGP SIGNATURE-----
Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random
Pull randomness updates from Ted Ts'o:
"Cleanups and bug fixes to /dev/random, add a new getrandom(2) system
call, which is a superset of OpenBSD's getentropy(2) call, for use
with userspace crypto libraries such as LibreSSL.
Also add the ability to have a kernel thread to pull entropy from
hardware rng devices into /dev/random"
* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
hwrng: Pass entropy to add_hwgenerator_randomness() in bits, not bytes
random: limit the contribution of the hw rng to at most half
random: introduce getrandom(2) system call
hw_random: fix sparse warning (NULL vs 0 for pointer)
random: use registers from interrupted code for CPU's w/o a cycle counter
hwrng: add per-device entropy derating
hwrng: create filler thread
random: add_hwgenerator_randomness() for feeding entropy from devices
random: use an improved fast_mix() function
random: clean up interrupt entropy accounting for archs w/o cycle counters
random: only update the last_pulled time if we actually transferred entropy
random: remove unneeded hash of a portion of the entropy pool
random: always update the entropy pool under the spinlock
rng_get_data() returns the number of bytes read from the hardware.
The entropy argument to add_hwgenerator_randomness() is passed
directly to credit_entropy_bits() so we should be passing the
number of bits, not bytes here.
Fixes: be4000bc46 "hwrng: create filler thread"
Acked-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This reverts commit e052dbf554.
Now that we use the virtio ->scan() function to register with the hwrng
core, we will not get read requests till probe is successfully finished.
So revert the workaround we had in place to refuse read requests while
we were not yet setup completely.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>