Most hw_random devices return entropy which is assumed to be of full
quality, but driver authors don't bother setting the quality knob. Some
hw_random devices return less than full quality entropy, and then driver
authors set the quality knob. Therefore, the entropy crediting should be
opt-out rather than opt-in per-driver, to reflect the actual reality on
the ground.
For example, the two Raspberry Pi RNG drivers produce full entropy
randomness, and both EDK2 and U-Boot's drivers for these treat them as
such. The result is that EFI then uses these numbers and passes the to
Linux, and Linux credits them as boot, thereby initializing the RNG.
Yet, in Linux, the quality knob was never set to anything, and so on the
chance that Linux is booted without EFI, nothing is ever credited.
That's annoying.
The same pattern appears to repeat itself throughout various drivers. In
fact, very very few drivers have bothered setting quality=1024.
Looking at the git history of existing drivers and corresponding mailing
list discussion, this conclusion tracks. There's been a decent amount of
discussion about drivers that set quality < 1024 -- somebody read and
interepreted a datasheet, or made some back of the envelope calculation
somehow. But there's been very little, if any, discussion about most
drivers where the quality is just set to 1024 or unset (or set to 1000
when the authors misunderstood the API and assumed it was base-10 rather
than base-2); in both cases the intent was fairly clear of, "this is a
hardware random device; it's fine."
So let's invert this logic. A hw_random struct's quality knob now
controls the maximum quality a driver can produce, or 0 to specify 1024.
Then, the module-wide switch called "default_quality" is changed to
represent the maximum quality of any driver. By default it's 1024, and
the quality of any particular driver is then given by:
min(default_quality, rng->quality ?: 1024);
This way, the user can still turn this off for weird reasons (and we can
replace whatever driver-specific disabling hacks existed in the past),
yet we get proper crediting for relevant RNGs.
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Rework CAAM RNG implementation as follows:
- Make use of the fact that HWRNG supports partial reads and will
handle such cases gracefully by removing recursion in caam_read()
- Convert blocking caam_read() codepath to do a single blocking job
read directly into requested buffer, bypassing any intermediary
buffers
- Convert async caam_read() codepath into a simple single
reader/single writer FIFO use-case, thus simplifying concurrency
handling and delegating buffer read/write position management to KFIFO
subsystem.
- Leverage the same low level RNG data extraction code for both async
and blocking caam_read() scenarios, get rid of the shared job
descriptor and make non-shared one as a simple as possible (just
HEADER + ALGORITHM OPERATION + FIFO STORE)
- Split private context from DMA related memory, so that the former
could be allocated without GFP_DMA.
NOTE: On its face value this commit decreased throughput numbers
reported by
dd if=/dev/hwrng of=/dev/null bs=1 count=100K [iflag=nonblock]
by about 15%, however commits that enable prediction resistance and
limit JR total size impact the performance so much and move the
bottleneck such as to make this regression irrelevant.
NOTE: On the bright side, this commit reduces RNG in kernel DMA buffer
memory usage from 2 x RN_BUF_SIZE (~256K) to 32K.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Horia Geantă <horia.geanta@nxp.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Iuliana Prodan <iuliana.prodan@nxp.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-imx@nxp.com
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Based on commit 6b80ea389a ("crypto: change transient busy return code to -ENOSPC"),
change the return code of caam_jr_enqueue function to -EINPROGRESS, in
case of success, -ENOSPC in case the CAAM is busy (has no space left
in job ring queue), -EIO if it cannot map the caller's descriptor.
Update, also, the cases for resource-freeing for each algorithm type.
This is done for later use, on backlogging support in CAAM.
Signed-off-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Reviewed-by: Horia Geanta <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Commit 1b46c90c8e ("crypto: caam - convert top level drivers to libraries")
changed entry and exit points behavior for caamalg,
caamalg_qi, caamalg_qi2, caamhash, caampkc, caamrng.
For example, previously caam_pkc_init() and caam_pkc_exit() were
module entry/exit points. This means that if an error would happen
in caam_pkc_init(), then caam_pkc_exit() wouldn't have been called.
After the mentioned commit, caam_pkc_init() and caam_pkc_exit()
are manually called - from jr.c. caam_pkc_exit() is called
unconditionally, even if caam_pkc_init() failed.
Added a global variable to keep the status of the algorithm
registration and free of resources.
The exit point of caampkc/caamrng module is executed only if the
registration was successful. Therefore we avoid double free of
resources in case the algorithm registration failed.
Fixes: 1b46c90c8e ("crypto: caam - convert top level drivers to libraries")
Signed-off-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Reviewed-by: Horia Geanta <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The CAAM driver used to put its debug messages inside #ifdef DEBUG and
then prints the messages at KERN_ERR level. Replace this with proper
functions printing at KERN_DEBUG level. The #ifdef DEBUG gets
unnecessary when the right functions are used.
This replaces:
- print_hex_dump(KERN_ERR ...) inside #ifdef DEBUG with
print_hex_dump_debug(...)
- dev_err() inside #ifdef DEBUG with dev_dbg()
- printk(KERN_ERR ...) inside #ifdef DEBUG with dev_dbg()
Some parts of the driver use these functions already, so it is only
consequent to use the debug function consistently.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently we allow top level code, i.e. that which sits between the
low level (HW-specific) drivers and crypto API, to be built as several
drivers: caamalg, caamhash, caam_pkc, caamrng, caamalg_qi.
There is no advantage in this, more it interferes with adding support
for deferred probing (there are no corresponding devices and thus
no bus).
Convert these drivers and call init() / exit() manually at the right
time.
Move algorithms initialization at JR probe / remove time:
-the first probed JR registers the crypto algs
-the last removed JR unregisters the crypto algs
Note: caam_qi_init() is called before JR platform devices creation
(of_populate_bus()), such that QI interface is initialized when
the caam/qi algorithms are registered in the JR driver (by calling
caam_qi_algapi_init().
While here, fix the Kconfig entries under CRYPTO_DEV_FSL_CAAM_JR
to be aligned.
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The of_find_device_by_node() takes a reference to the underlying device
structure, we should release that reference.
Fixes: 35af640386 ("crypto: caam - Check for CAAM block presence before registering with crypto layer")
Fixes: b189817cf7 ("crypto: caam/qi - add ablkcipher and authenc algorithms")
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Wen Yang <yellowriver2010@hotmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Era 10 changes the register map.
The updates that affect the drivers:
-new version registers are added
-DBG_DBG[deco_state] field is moved to a new register -
DBG_EXEC[19:16] @ 8_0E3Ch.
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Previously, a tree-wide change added SPDX license identifiers to
files lacking licensing information:
b24413180f ("License cleanup: add SPDX GPL-2.0 license identifier to files with no license")
To be consistent update the rest of the files:
-files with license specified by means of MODULE_LICENSE()
-files with complete license text
-Kconfig
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Fix the following smatch warnings:
drivers/crypto/caam/caamalg.c:2350 aead_edesc_alloc() warn: we tested 'src_nents' before and it was 'true'
drivers/crypto/caam/caamrng.c:351 caam_rng_init() error: no modifiers for allocation.
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Commit 4464a7d4f5
("crypto: caam - remove error propagation handling")
removed error propagation handling only from caamalg.
Do this in all other places: caamhash, caamrng.
Update descriptors' lengths appropriately.
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
"The preferred form for passing a size of a struct is the following:
p = kmalloc(sizeof(*p), ...);
....
The preferred form for allocating a zeroed array is the following:
p = kcalloc(n, sizeof(...), ...); "
,so do as suggested.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Reviewed-by: Horia Geant? <horia.geanta@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The hwrng output buffers (2) are cast inside of a a struct (caam_rng_ctx)
allocated in one DMA-tagged region. While the kernel's heap allocator
should place the overall struct on a cacheline aligned boundary, the 2
buffers contained within may not necessarily align. Consenquently, the ends
of unaligned buffers may not fully flush, and if so, stale data will be left
behind, resulting in small repeating patterns.
This fix aligns the buffers inside the struct.
Note that not all of the data inside caam_rng_ctx necessarily needs to be
DMA-tagged, only the buffers themselves require this. However, a fix would
incur the expense of error-handling bloat in the case of allocation failure.
Cc: stable@vger.kernel.org
Signed-off-by: Steve Cornelius <steve.cornelius@freescale.com>
Signed-off-by: Victoria Milhoan <vicki.milhoan@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The layer which registers with the crypto API should check for the presence of
the CAAM device it is going to use. If the platform's device tree doesn't have
the required CAAM node, the layer should return an error and not register the
algorithms with crypto API layer.
Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Found by the kbuild test robot, the first argument to caam_init_rng
has a spurious ampersand.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch allocates memory from DMAable region to the caam_rng_ctx object,
earlier it had been statically allocated which resulted in errorneous
behaviour on inserting the caamrng module at the runtime.
Signed-off-by: Nitesh Lal <NiteshNarayanLal@freescale.com>
Acked-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
- Earlier interface layers - caamalg, caamhash, caamrng were
directly using the Controller driver private structure to access
the Job ring.
- Changed the above to use alloc/free API's provided by Job Ring Drive
Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Reviewed-by: Garg Vakul-B16394 <vakul@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The SEC Job Rings are now available as individual devices.
This would enable sharing of job rings between kernel and
user space. Job Rings can now be dynamically bound/unbound
from kernel.
Changes are made in the following layers of CAAM Driver
1. Controller driver
- Does basic initialization of CAAM Block.
- Creates platform devices for Job Rings.
(Earlier the initialization of Job ring was done
by the controller driver)
2. JobRing Platform driver
- Manages the platform Job Ring devices created
by the controller driver
Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Reviewed-by: Garg Vakul-B16394 <vakul@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
If the CAAM driver initialization failed (due to various reasons, e.g. RNG4
initialization failed), then the registration of hash/algorithms/rng shouldn't
take place. This patch adds the necessary code to prevent this registration.
Signed-off-by: Alex Porosanu <alexandru.porosanu@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
SHARE_WAIT, whilst more optimal for association-less crypto,
has the ability to start thrashing the CCB descriptor/key
caches, given high levels of traffic across multiple security
associations (and thus keys).
Switch to using the SERIAL sharing type, which prefers
the last used CCB for the SA. On a 2-DECO platform
such as the P3041, this can improve performance by
about 3.7%.
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In some device trees of previous version, there were string "fsl,sec4.0".
To be backward compatible with device trees, we first check "fsl,sec-v4.0",
if it fails, then check for "fsl,sec4.0".
Signed-off-by: Shengzhou Liu <Shengzhou.Liu@freescale.com>
extended to include new hash and rng code, which was omitted from
the previous version of this patch during a rebase of the SDK
version.
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
caam_read copies random bytes from two buffers into output.
caam rng can fill empty buffer 0xffff bytes at a time,
but the buffer sizes are rounded down to multiple of cacheline size.
Signed-off-by: Yuan Kang <Yuan.Kang@freescale.com>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>